Karla Moresco | Universidade Federal do Rio Grande do Sul (original) (raw)

Papers by Karla Moresco

Research paper thumbnail of Long-term Effect of Lifestyle Interventions on the Cardiovascular and All-Cause Mortality of Subjects With Prediabetes and Type 2 Diabetes: A Systematic Review and Meta-analysis

Diabetes Care

BACKGROUND Lifestyle interventions improve the metabolic control of individuals with hyperglycemi... more BACKGROUND Lifestyle interventions improve the metabolic control of individuals with hyperglycemia. PURPOSE We aimed to determine the effect of lifestyle interventions on cardiovascular and all-cause mortality in this population. DATA SOURCES Searches were made through MEDLINE, Cochrane CENTRAL, Embase, and Web of Science (no date/language restriction, until 15 May 2022). STUDY SELECTION We included randomized clinical trials (RCTs) of subjects with prediabetes and type 2 diabetes, comparing intensive lifestyle interventions with usual care, with a minimum of 2 years of active intervention. DATA EXTRACTION Data from the 11 RCTs selected were extracted in duplicate. A frequentist and arm-based meta-analysis was performed with random-effects models to estimate relative risk (RR) for mortality, and heterogeneity was assessed through I2 metrics. A generalized linear mixed model (GLMM) was used to confirm the findings. DATA SYNTHESIS Lifestyle interventions were not superior to usual car...

Research paper thumbnail of Tecnologia para obtenção de produto desidratado de pimenteira

Research paper thumbnail of Long-term effect of lifestyle interventions in the cardiovascular and all-cause mortality of subjects with prediabetes and type 2 diabetes: A systematic review and meta-analysis

Background: Lifestyle interventions improve the metabolic control of individuals with hypergly... more Background: Lifestyle interventions improve the metabolic control of individuals with hyperglycemia. We aimed to determine the effect of lifestyle interventions on cardiovascular and all-cause mortality in this population. Methods: Searches were made through MEDLINE, Cochrane CENTRAL, Embase, and Web of Science (no date/language restriction, until May 15, 2022). Were included randomized clinical trials (RCTs) of subjects with prediabetes and type 2 diabetes, comparing intensive lifestyle interventions to usual care, and a minimum of 2 years of active intervention. Data from the 11 RCTs selected were extracted in duplicate. A frequentist and arm-based meta-analysis was performed using random effects models to estimate relative risk (RR) for mortality, and heterogeneity was assessed through I2 metrics. A generalized linear mixed model (GLMM) was performed to confirm the findings. Results: Lifestyle interventions were not superior to usual care in reducing cardiovascular (RR, 0.99; ...

Research paper thumbnail of Exposición crónica a acroleína en ratas wistar: los efectos de los extractos de guaraná

Previous studies have reported that acrolein, may exert harmful effects on the brain. However, in... more Previous studies have reported that acrolein, may exert harmful effects on the brain. However, information regarding the neuroprotective properties of guarana against acrolein is not available. Due to the lack of research, we initiated the current study to investigate the effects of guarana extracts on acrolein-induced toxicity in the liver and the central nervous system of Wistar Rats. Twelve groups of 60 days old Wistar rats treated with guarana extracts (150, 250, and 350 mg/kg/day) for 8 weeks, were challenged with acrolein (2.5 mg/kg/day). Several parameters associated with oxidative damage to the brain and hepatic function, as well as behavior were evaluated. All tested concentrations of guarana extracts exerted protective effects against acrolein induced damage. No hepatic and oxidative damages or behavioral changes were observed in guarana control groups. To the best of our knowledge, this is the first study of its kind and therefore a milestone in this field.Estudios anteri...

Research paper thumbnail of Determinação de carotenoides e atividade antioxidante de pimentas provenientes da região amazônica

Tres genotipos de pimentas (Capsicum annun L. e Capsicum chinense Jacq) foram analisados quanto a... more Tres genotipos de pimentas (Capsicum annun L. e Capsicum chinense Jacq) foram analisados quanto ao perfil de carotenoides e atividade antioxidante. Os carotenoides all-trans-luteina e zeaxantina foram encontrados em todas as amostras analisadas. O genotipo IAN 186301 se destacou em relacao aos carotenoides ?-criptoxantina, ?-caroteno e ?-caroteno, bem como em relacao ao teor de carotenoides totais. Para a capacidade antioxidante a pimenta IAN 186301 tambem apresentou a maior atividade antioxidante (2061,57 g/g DPPH?), enquanto a pimenta IAN 186313 apresentou a menor atividade antioxidante, (4905,06 g/g DPPH?). Conclui-se que o genotipo IAN 186301 (Capsicum annun L.) apresenta potencial para ser selecionado em trabalhos de melhoramento genetico para obtencao de variedades com alto teor de carotenoides e capacidade antioxidante.

Research paper thumbnail of Efeitos terapêuticos de Achyrocline satureioides (Lam.) : estudos in vivo e in vitro

Achyrocline satureioides (Asteraceae) ou "Marcela" é uma planta nativa de países latino... more Achyrocline satureioides (Asteraceae) ou "Marcela" é uma planta nativa de países latino-americanos e, apesar do seu uso generalizado na medicina tradicional, as propriedades químicas e biológicas que sustentam seu uso fitoterápico, ainda não foram completamente caracterizadas. Neste trabalho apresentamos benefícios terapêuticos de extratos de Achyrocline satureioides, através de estudos in vitro e in vivo. Avaliou-se o perfil químico, potencial antioxidante in vitro e atividade antimicrobiana de três extratos de Achyrocline satureioides. Dentre os extratos testados, o extrato hidroetanólico exibiu atividade antioxidante em concentrações de 34 μg/mL, e apresentou um amplo espectro de atividade antimicrobiana (100 a 200 mg/mL) contra bactérias patogênicas intestinais. Os efeitos antibacterianos foram superiores aos exercidos pela amoxicilina, quando testados contra Bacillus cereus e Staphylococcus aureus. Como estudos sobre o efeito do uso indiscriminado de infusões de plantas durante a gravidez são limitados, neste trabalho, também investigamos os efeitos da suplementação em ratas wistar com dois extratos de Achyrocline satureioides, um extrato aquoso (47mg/Kg/dia) e um extrato hidroetanólico (35mg/Kg/dia), administrados durante a gestação e lactação. Nossos dados sugerem que tanto o extrato aquoso quanto o hidroetanólico podem induzir sintomas de toxicidade nas concentrações testadas, no que se refere ao índice de nascimentos dos filhotes, diminuição da sobrevivência neonatal, além de causar alterações significativas específicas nos tecidos quanto aos parametros enzimáticos tanto das mães como dos filhotes fornecendo evidências que podem justificar a necessidade de controle na suplementação na gestação. A administração oral de um extrato hidroetanólico de A. satureioides também produziu atividade anti-hiperglicêmica promissora em ratos. Sendo comparável ao fármaco controle positivo: a acarbose. Este efeito foi observado em ratos que ingeriram níveis elevados de maltose e amido, e também em modelo de indução de diabetes mellitus (DM) com estreptozotocina. Para investigar o mecanismo de ação do extrato, determinamos seus efeitos inibitórios sobre maltase e α-amilase pancreática. O nível de extrato associado a 50% de inibição enzimática (IC50) foi de 185,21 μg/mL para maltase e 265,72 μg / mL para α-amilase pancreática. Uma investigação mais profunda dos constituintes de A. satureioides mostrou que o flavonoide, achyrobichalcona, produziu a maior inibição das glicosidases (IC50 de 4,74 μM para α-amilase e 6,71 μM para maltase), o que foi consistente com os nossos resultados de modelagem molecular. Estes achados sugerem uma potencial aplicação de A. satureioides como agente terapêutico em DM. As atividades antioxidantes, antimicrobianas e hiperglicêmica de parecem estar positivamente correlacionadas com a quantidade de flavonoides. Em conclusão, nossos resultados mostraram evidências de atividades antioxidante, antimicrobiana e hipoglicêmica convidando a pesquisas futuras sobre seu potencial uso como agente co-adjuvante terapêutico tanto para o tratamento das doenças gastrointestinais que podem apresentar altas taxas de resistência a antibióticos, bem como no DM. Contudo, são necessárias mais investigações para verificar os seus efeitos sobre a saúde.Achyrocline satureioides (Asteraceae) or “Marcela” has been widely used in traditional medicine; however, chemical and biological properties supporting its phytotherapeutic usage are still poorly studied. In this work we present therapeutic benefits of extracts of Achyrocline satureioides, through in vitro and in vivo studies. We evaluated the chemical profiles of the dried extracts, along with antioxidant potential and antimicrobial activity against intestinal pathogenic bacteria. Our data suggest that dried A. satureioides extracts exert greater antibacterial effects than the antibiotic amoxicillin when tested against Bacillus cereus and Staphylococcus aureus. The antioxidant and antimicrobial activities of A. satureioides extracts appear to positively correlate with the amount of flavonoids measured in each extract. Our results provide evidence for the antioxidant and antimicrobial activities of A. satureioides extracts against intestinal pathogens. These findings justify further research regarding the potential for A. satureioides extracts as co-adjuvants to treat bacterial-induced intestinal diseases that may present high rates of antibiotic resistance. Studies regarding the indiscriminate use of plant infusions during pregnancy are limited. Recent reports have shown that chronic flavonoid supplementation induces toxicity in vivo and raises the mortality rates of healthy subjects. Therefore, we investigated whether supplementation of pregnant and lactating Wistar rats with two AS inflorescence extracts, consisting of an aqueous extract similar to a tea (47 mg/kg/day) and a hydroethanolic extract (35 mg/kg/day) with a higher flavonoid content, could induce…

Research paper thumbnail of Chronic acrolein exposure in Wistar rats: The effects of guarana extracts

Journal of Functional Foods, 2019

Previous studies have reported that acrolein, may exert harmful effects on the brain. However, in... more Previous studies have reported that acrolein, may exert harmful effects on the brain. However, information regarding the neuroprotective properties of guarana against acrolein is not available. Due to the lack of research, we initiated the current study to investigate the effects of guarana extracts on acrolein-induced toxicity in the liver and the central nervous system of Wistar Rats. Twelve groups of 60 days old Wistar rats treated with guarana extracts (150, 250, and 350 mg/kg/day) for 8 weeks, were challenged with acrolein (2.5 mg/kg/day). Several parameters associated with oxidative damage to the brain and hepatic function, as well as behavior were evaluated. All tested concentrations of guarana extracts exerted protective effects against acrolein induced damage. No hepatic and oxidative damages or behavioral changes were observed in guarana control groups. To the best of our knowledge, this is the first study of its kind and therefore a milestone in this field.

Research paper thumbnail of Guarana (Paullinia cupanaMart.) alters gut microbiota and modulates redox status, partially via caffeine in Wistar rats

Phytotherapy Research, 2018

Microbiota alterations are observed in pathological conditions, and their regulation is a subject... more Microbiota alterations are observed in pathological conditions, and their regulation is a subject of great interest. Gut microbes are affected by diet, and plant polyphenols may have positive effect on gut microbiota; however, plant-derived extracts may have toxic effects. Guarana (Paullinia cupana Mart.) is a nontraditional medicinal plant applied worldwide. Guarana yields an alkaloid and polyphenol-rich seed with antimicrobial, antioxidant, and anti-inflammatory properties, where caffeine is the major compound. We evaluated the effects of guarana seed powder (GSP) and purified caffeine on gut microbial composition and redox and inflammatory parameters in Wistar rats after 21 days of treatment. Fecal microbiota was analyzed utilizing 16S rDNA sequencing. Antioxidant enzymes activities from liver, kidney, and colon, as well as oxidative damage markers, were evaluated. Total nonenzymatic antioxidant potential was also evaluated. Microbiota was altered by both treatments, GSP and caffeine, without loss of diversity. In the liver, the kidney, and the colon, we observed a decrease in the antioxidant enzymes activities in the GSP group with no increase in the expression of oxidative damage markers, although some enzymes were also regulated by caffeine. Taken together, these results suggested that GSP ameliorates redox parameters but negatively affected gut microbiota, partially via caffeine.

Research paper thumbnail of Anticancer activity of flavonoids isolated from Achyrocline satureioides in gliomas cell lines

Toxicology in vitro : an international journal published in association with BIBRA, 2018

Achyrocline satureioides, popularly known as "marcela", is a medicinal plant found in S... more Achyrocline satureioides, popularly known as "marcela", is a medicinal plant found in South America. This plant is rich in flavonoids, which have been reported to exert numerous biological activities. The aim of this study was to purify, identify and evaluate the mechanisms underlining anticancer activity of A. satureioides flavonoids in glioma cell lines (U87, U251 and C6) as well as their comparative toxicity in normal brain cells (primary astrocytes, neurons and organotypic hippocampal cultures). The main flavonoids present in A. satureioides are luteolin, quercetin, 3-O-methyl-quercetin and achyrobichalcone, the later a very unique metabolite present in this plant. Isolated flavonoids as well as A. satureioides extracts reduced proliferation and clonogenic survival, and induced apoptosis of glioma cell lines. In addition, A. satureioides flavonoids potentiated the cytotoxic effect and apoptosis induction by the glioma chemotherapeutic temozolomide (TMZ). Importantly, A...

Research paper thumbnail of Protective effect of a hydrogel containing Achyrocline satureioides extract-loaded nanoemulsion against UV-induced skin damage

Journal of Photochemistry and Photobiology B: Biology, 2016

Achyrocline satureioides is a medicinal plant widely used in South America that exhibits a well-d... more Achyrocline satureioides is a medicinal plant widely used in South America that exhibits a well-documented antioxidant activity. Such activity has been related to their main aglycone flavonoids quercetin, luteolin, and 3-Omethylquercetin (3MQ). This study addresses the development of antioxidant hydrogels containing an A. satureioides extract-loaded nanoemulsions aimed at topical application. The systems investigated were A. satureioides extract-loaded nanoemulsions (ASNE) obtained by spontaneous emulsification procedure formulated in semisolid hydrogels composed of Carbopol® Ultrez 20 (HASNE). Hydrogels exhibit a non-Newtonian pseudoplastic behavior. A higher release of 3MQ from ASNE (3.61 μg/cm 2 /h) was observed when compared with HASNE (2.83 μg/cm 2 /h). Different parameters that may have an influence on the retention of flavonoids into the skin were investigated by using a Franz-type diffusion cells. Indeed, the amount of formulation applied on donor compartment was found to play a crucial role. At the optimized conditions, retention of approximately 2 μg/cm 2 of flavonoids was detected into the skin. A higher retention of 3MQ was detected (approximately 1.0 μg/ cm 2) in comparison with the other flavonoids. Finally, a protection the porcine ear skin by formulations, against oxidative stress generated by UVA/UVB light was demonstrated by means of TBARS, protein carbonylation, and protein thiol content assays. The overall results showed the potential of the formulations developed in this study for the prevention of oxidative stress on the skin.

Research paper thumbnail of Supplementation with Achyrocline satureioides Inflorescence Extracts to Pregnant and Breastfeeding Rats Induces Tissue-Specific Changes in Enzymatic Activity and Lower Neonatal Survival

Biomedicines, 2017

Achyrocline satureioides (AS, family Asteraceae) is a plant widely used in traditional medicine f... more Achyrocline satureioides (AS, family Asteraceae) is a plant widely used in traditional medicine for stomach, digestive, and gastrointestinal disorders during pregnancy. Studies regarding the indiscriminate use of plant infusions during pregnancy are limited. Recent reports have shown that chronic flavonoid supplementation induces toxicity in vivo and raises the mortality rates of healthy subjects. Therefore, we investigated whether supplementation of pregnant and lactating Wistar rats with two AS inflorescence extracts, consisting of an aqueous (AQ) extract similar to a tea (47 mg•kg −1 •day) and a hydroethanolic (HA) extract (35 mg•kg −1 •day −1) with a higher flavonoid content, could induce redox-related side effects. Total reactive antioxidant potential (TRAP), thiobarbituric reactive species (TBARS), and total reduced thiol (SH) content were evaluated. Superoxide dismutase (SOD) and catalase (CAT) activities were additionally quantified. Our data suggest that both AQ and HA of AS inflorescence extracts may induce symptoms of toxicity in concentrations of (47 mg•kg −1 •day) and (35 mg•kg −1 •day −1), respectively, in mothers regarding the delivery index and further decrease of neonatal survival. Of note, significant tissue-specific changes in maternal (liver, kidney, heart, and hippocampus) and pups (liver and kidney) biochemical oxidative parameters were observed. Our findings provide evidence that may support the need to control supplementation with the AQ of AS inflorescence extracts during gestation due to potential toxicity in vivo, which might be related, at least in part, to changes in tissue-specific redox homeostasis and enzymatic activity.

Research paper thumbnail of Effects of Achyrocline satureioides Inflorescence Extracts against Pathogenic Intestinal Bacteria: Chemical Characterization, In Vitro Tests, and In Vivo Evaluation

Evidence-Based Complementary and Alternative Medicine, 2017

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-drie... more Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared from the aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol). The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17 mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of ...

Research paper thumbnail of Effect of Paullinia cupana Mart. Commercial Extract During the Aging of Middle Age Wistar Rats: Differential Effects on the Hippocampus and Striatum

Neurochemical Research, 2017

treatment (saline, CGE, or caffeine). Solutions were administered daily by oral gavage for 6 mont... more treatment (saline, CGE, or caffeine). Solutions were administered daily by oral gavage for 6 months. Open field and novel object recognition tasks were performed before and after treatment. Biochemical analyses were carried out on the hippocampus and striatum. Our open field data showed an increase in exploratory activity and a decrease in anxiety-like behavior with caffeine but not with the CGE treatment. In the CGE-treated group, catalase activity decreased in the hippocampus and increased in the striatum. Analyses of the hippocampus and striatum indicate that CGE and/ or caffeine altered some of the analyzed parameters in a tissue-specific manner. Our data suggest that CGE intake does not improve cognitive development, but modifies the oxidative stress machinery and neurodegenerative-signaling pathway, inhibiting pro-survival pathway molecules in the hippocampus and striatum. This may contribute to the development of unfavorable microenvironments in the brain and neurodegenerative disorders.

Research paper thumbnail of Changes in bioactive compounds and antioxidant activity of peppers from the Amazon region

Pesquisa Agropecuaria Tropical, Dec 1, 2014

Research paper thumbnail of Effects of different products of peach (Prunus persica L. Batsch) from a variety developed in southern Brazil on oxidative stress and inflammatory parameters in vitro and ex vivo

Journal of Clinical Biochemistry and Nutrition, 2014

Antioxidant, anti glycation and anti inflammatory activities of fresh and conserved peach fruits ... more Antioxidant, anti glycation and anti inflammatory activities of fresh and conserved peach fruits (Prunus persica L. Batsch) were compared. Fresh peach pulps, peels, preserve peach pulps and the preserve syrup were prepared at equal concentrations. Rat liver, kidney and brain cortex tissue slices were pre incubated with peach samples, subjected to oxidative stress with FeSO4 and hydrogen peroxide. Fresh peach pulps and peel conferred higher protection against cytotoxicity and oxidative stress than preserve peach pulps in most tissues. Release of tumor necrosis factor α and interleukin 1β was also significantly decreased by Fresh peach pulps and peel, followed by preserve peach pulps. Total phenolic determination and HPLC analysis of carotenoids showed that the content of secondary metabolites in Fresh peach pulps and peel is signifi cantly higher than in preserve peach pulps, while the syrup had only small or trace amounts of these compounds. Fresh peach pulps and Peel demonstrated high antioxidant and anti inflammatory effects preventing against induced damage.

Research paper thumbnail of Preventive supplementation with fresh and preserved peach attenuates CCl4-induced oxidative stress, inflammation and tissue damage

The Journal of Nutritional Biochemistry, 2014

The present study was elaborated to comparatively evaluate the preventive effect of different pea... more The present study was elaborated to comparatively evaluate the preventive effect of different peach-derived products obtained from preserved fruits (Syrup and Preserve Pulp Peach [PPP]) and from fresh peels and pulps (Peel and Fresh Pulp Peach [FPP]) in a model of liver/renal toxicity and inflammation induced by carbon tetrachloride (CCl 4) in rats. Tissue damage (carbonyl, thiobarbituric acid reactive species and sulfhydril), antioxidant enzymes activity (catalase and superoxide dismutase) and inflammatory parameters [tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels, and receptor for advanced glycation endproducts (RAGE) and nuclear factor (NF)κB-p65 immunocontent] were investigated. Our findings demonstrated that Peel, PPP and FPP (200 or 400 mg/kg) daily administration by oral gavage for 30 days conferred a significant protection against CCl 4-induced antioxidant enzymes activation and, most importantly, oxidative damage to lipids and proteins as well as blocked induction of inflammatory mediators such as TNF-α, IL-1β, RAGE and NFκB. This antioxidant/antiinflammatory effect seems to be associated with the abundance of carotenoids and polyphenols present in peach-derived products, which are enriched in freshfruit-derived preparations (Peel and FPP) but are also present in PPP. The Syrupwhich was the least enriched in antioxidantsdisplayed no protective effect in our experiments. These effects cumulated in decreased levels of transaminases and lactate dehydrogenase leakage into serum and maintenance of organ architecture. Therefore, the herein presented results show evidence that supplementation with peach products may be protective against organ damage caused by oxidative stress, being interesting candidates for production of antioxidant-enriched functional foods.

Research paper thumbnail of 1170-P: Long-Term Effects of Lifestyle Changes in Subjects with Prediabetes and Type 2 Diabetes on Cardiovascular and All-Cause Mortality: A Systematic Review with Meta-analysis of Randomized Clinical Trials

Diabetes

Long-term RCTs have shown that lifestyle interventions (LI) can prevent T2DM in individuals with ... more Long-term RCTs have shown that lifestyle interventions (LI) can prevent T2DM in individuals with prediabetes, improve glycemic control in individuals with T2DM, as well as improve lipid profile and lower blood pressure in both. However, the impact of these interventions on cardiovascular (CV) and total mortality is still not clear. Therefore, we conducted a systematic review with meta-analysis to determine the long-term efficacy of LI on CV and all-cause mortality in subjects with prediabetes and T2DM. We searched PubMed, Cochrane CENTRAL, Embase, Web of Science, protocol records, and reference lists of relevant publications until December 2021. We selected RCTs including adults with prediabetes and T2DM that evaluated LI with at least 2 years of duration, with or without post-trial follow-up. The main outcomes consisted of CV and all-cause mortality. We used the RoB 2.0 tool to evaluate the risk of bias and the GRADE approach for the overall certainty of evidence. Meta-analysis was...

Research paper thumbnail of DELAYED NEUROCHEMICAL EFFECTS OF PRENATAL EXPOSURE TO MeHg IN THE CEREBELLUM OF DEVELOPING RATS

Toxicology letters, Jan 16, 2017

Human fetuses and neonates are particularly vulnerable to methylmercury (MeHg)-induced brain dama... more Human fetuses and neonates are particularly vulnerable to methylmercury (MeHg)-induced brain damage and are sensitive even to low exposure levels. Previous work of our group evidence that prenatal exposure to MeHg causes cognitive and behavioral alterations and disrupt hippocampus signaling. The current study aimed to investigate the effect of gestational exposure of rats to MeHg at low doses (1 or 2 mg/Kg) on parameters of redox imbalance and key signaling pathways in the cerebellum of their offspring. Pregnant females received MeHg (treated group) or 0.9% saline water (control group) by gavage in alternated days from gestational day 5 (GD5) until parturition and analyzes were proceed in the cerebellum of 30-day-old pups. We found increased lipid peroxidation and protein carbonylation levels as well as decreased SH content in pups prenatally exposed to 2 mg/kg MeHg. In addition, misregulated SOD/catalase activities supported imbalanced redox equilibrium. We found decreased GSK3β(Se...

Research paper thumbnail of Desenvolvimento de nanocápsula de extrato de Achyrocline Satureioides (Marcela) como adjuvante no tratamento da diabetes

Research paper thumbnail of Characterization of a novel antioxidant peptide from feather keratin hydrolysates

New biotechnology, Jan 14, 2018

Feather hydrolysates were obtained through submerged cultivation of 50 g/L feathers with Chryseob... more Feather hydrolysates were obtained through submerged cultivation of 50 g/L feathers with Chryseobacterium sp. kr6. Culture supernatants, displaying antioxidant properties, as evaluated by the 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging method, were partially purified by gel-filtration chromatography. Fractions showing scavenging activity were pooled, lyophilized and tested at different concentrations (0.1-1.0 mg/mL) by the total reactive antioxidant potential (TRAP) method, showing promising antioxidant capacities. Antioxidant activities of the partially purified feather hydrolysate (PPFH; 24.5 μg) were demonstrated by its ability to scavenge hydroxyl radicals and to inhibit lipid peroxidation. In addition, PPFH (0.24-24.5 μg) was found to reduce ferric ion (Fe), but did not display Fe-chelating activity. Thus, the main antioxidant activities could be related to the donation of hydrogen atoms, electron transfer and scavenging of hydroxyl rad...

Research paper thumbnail of Long-term Effect of Lifestyle Interventions on the Cardiovascular and All-Cause Mortality of Subjects With Prediabetes and Type 2 Diabetes: A Systematic Review and Meta-analysis

Diabetes Care

BACKGROUND Lifestyle interventions improve the metabolic control of individuals with hyperglycemi... more BACKGROUND Lifestyle interventions improve the metabolic control of individuals with hyperglycemia. PURPOSE We aimed to determine the effect of lifestyle interventions on cardiovascular and all-cause mortality in this population. DATA SOURCES Searches were made through MEDLINE, Cochrane CENTRAL, Embase, and Web of Science (no date/language restriction, until 15 May 2022). STUDY SELECTION We included randomized clinical trials (RCTs) of subjects with prediabetes and type 2 diabetes, comparing intensive lifestyle interventions with usual care, with a minimum of 2 years of active intervention. DATA EXTRACTION Data from the 11 RCTs selected were extracted in duplicate. A frequentist and arm-based meta-analysis was performed with random-effects models to estimate relative risk (RR) for mortality, and heterogeneity was assessed through I2 metrics. A generalized linear mixed model (GLMM) was used to confirm the findings. DATA SYNTHESIS Lifestyle interventions were not superior to usual car...

Research paper thumbnail of Tecnologia para obtenção de produto desidratado de pimenteira

Research paper thumbnail of Long-term effect of lifestyle interventions in the cardiovascular and all-cause mortality of subjects with prediabetes and type 2 diabetes: A systematic review and meta-analysis

Background: Lifestyle interventions improve the metabolic control of individuals with hypergly... more Background: Lifestyle interventions improve the metabolic control of individuals with hyperglycemia. We aimed to determine the effect of lifestyle interventions on cardiovascular and all-cause mortality in this population. Methods: Searches were made through MEDLINE, Cochrane CENTRAL, Embase, and Web of Science (no date/language restriction, until May 15, 2022). Were included randomized clinical trials (RCTs) of subjects with prediabetes and type 2 diabetes, comparing intensive lifestyle interventions to usual care, and a minimum of 2 years of active intervention. Data from the 11 RCTs selected were extracted in duplicate. A frequentist and arm-based meta-analysis was performed using random effects models to estimate relative risk (RR) for mortality, and heterogeneity was assessed through I2 metrics. A generalized linear mixed model (GLMM) was performed to confirm the findings. Results: Lifestyle interventions were not superior to usual care in reducing cardiovascular (RR, 0.99; ...

Research paper thumbnail of Exposición crónica a acroleína en ratas wistar: los efectos de los extractos de guaraná

Previous studies have reported that acrolein, may exert harmful effects on the brain. However, in... more Previous studies have reported that acrolein, may exert harmful effects on the brain. However, information regarding the neuroprotective properties of guarana against acrolein is not available. Due to the lack of research, we initiated the current study to investigate the effects of guarana extracts on acrolein-induced toxicity in the liver and the central nervous system of Wistar Rats. Twelve groups of 60 days old Wistar rats treated with guarana extracts (150, 250, and 350 mg/kg/day) for 8 weeks, were challenged with acrolein (2.5 mg/kg/day). Several parameters associated with oxidative damage to the brain and hepatic function, as well as behavior were evaluated. All tested concentrations of guarana extracts exerted protective effects against acrolein induced damage. No hepatic and oxidative damages or behavioral changes were observed in guarana control groups. To the best of our knowledge, this is the first study of its kind and therefore a milestone in this field.Estudios anteri...

Research paper thumbnail of Determinação de carotenoides e atividade antioxidante de pimentas provenientes da região amazônica

Tres genotipos de pimentas (Capsicum annun L. e Capsicum chinense Jacq) foram analisados quanto a... more Tres genotipos de pimentas (Capsicum annun L. e Capsicum chinense Jacq) foram analisados quanto ao perfil de carotenoides e atividade antioxidante. Os carotenoides all-trans-luteina e zeaxantina foram encontrados em todas as amostras analisadas. O genotipo IAN 186301 se destacou em relacao aos carotenoides ?-criptoxantina, ?-caroteno e ?-caroteno, bem como em relacao ao teor de carotenoides totais. Para a capacidade antioxidante a pimenta IAN 186301 tambem apresentou a maior atividade antioxidante (2061,57 g/g DPPH?), enquanto a pimenta IAN 186313 apresentou a menor atividade antioxidante, (4905,06 g/g DPPH?). Conclui-se que o genotipo IAN 186301 (Capsicum annun L.) apresenta potencial para ser selecionado em trabalhos de melhoramento genetico para obtencao de variedades com alto teor de carotenoides e capacidade antioxidante.

Research paper thumbnail of Efeitos terapêuticos de Achyrocline satureioides (Lam.) : estudos in vivo e in vitro

Achyrocline satureioides (Asteraceae) ou "Marcela" é uma planta nativa de países latino... more Achyrocline satureioides (Asteraceae) ou "Marcela" é uma planta nativa de países latino-americanos e, apesar do seu uso generalizado na medicina tradicional, as propriedades químicas e biológicas que sustentam seu uso fitoterápico, ainda não foram completamente caracterizadas. Neste trabalho apresentamos benefícios terapêuticos de extratos de Achyrocline satureioides, através de estudos in vitro e in vivo. Avaliou-se o perfil químico, potencial antioxidante in vitro e atividade antimicrobiana de três extratos de Achyrocline satureioides. Dentre os extratos testados, o extrato hidroetanólico exibiu atividade antioxidante em concentrações de 34 μg/mL, e apresentou um amplo espectro de atividade antimicrobiana (100 a 200 mg/mL) contra bactérias patogênicas intestinais. Os efeitos antibacterianos foram superiores aos exercidos pela amoxicilina, quando testados contra Bacillus cereus e Staphylococcus aureus. Como estudos sobre o efeito do uso indiscriminado de infusões de plantas durante a gravidez são limitados, neste trabalho, também investigamos os efeitos da suplementação em ratas wistar com dois extratos de Achyrocline satureioides, um extrato aquoso (47mg/Kg/dia) e um extrato hidroetanólico (35mg/Kg/dia), administrados durante a gestação e lactação. Nossos dados sugerem que tanto o extrato aquoso quanto o hidroetanólico podem induzir sintomas de toxicidade nas concentrações testadas, no que se refere ao índice de nascimentos dos filhotes, diminuição da sobrevivência neonatal, além de causar alterações significativas específicas nos tecidos quanto aos parametros enzimáticos tanto das mães como dos filhotes fornecendo evidências que podem justificar a necessidade de controle na suplementação na gestação. A administração oral de um extrato hidroetanólico de A. satureioides também produziu atividade anti-hiperglicêmica promissora em ratos. Sendo comparável ao fármaco controle positivo: a acarbose. Este efeito foi observado em ratos que ingeriram níveis elevados de maltose e amido, e também em modelo de indução de diabetes mellitus (DM) com estreptozotocina. Para investigar o mecanismo de ação do extrato, determinamos seus efeitos inibitórios sobre maltase e α-amilase pancreática. O nível de extrato associado a 50% de inibição enzimática (IC50) foi de 185,21 μg/mL para maltase e 265,72 μg / mL para α-amilase pancreática. Uma investigação mais profunda dos constituintes de A. satureioides mostrou que o flavonoide, achyrobichalcona, produziu a maior inibição das glicosidases (IC50 de 4,74 μM para α-amilase e 6,71 μM para maltase), o que foi consistente com os nossos resultados de modelagem molecular. Estes achados sugerem uma potencial aplicação de A. satureioides como agente terapêutico em DM. As atividades antioxidantes, antimicrobianas e hiperglicêmica de parecem estar positivamente correlacionadas com a quantidade de flavonoides. Em conclusão, nossos resultados mostraram evidências de atividades antioxidante, antimicrobiana e hipoglicêmica convidando a pesquisas futuras sobre seu potencial uso como agente co-adjuvante terapêutico tanto para o tratamento das doenças gastrointestinais que podem apresentar altas taxas de resistência a antibióticos, bem como no DM. Contudo, são necessárias mais investigações para verificar os seus efeitos sobre a saúde.Achyrocline satureioides (Asteraceae) or “Marcela” has been widely used in traditional medicine; however, chemical and biological properties supporting its phytotherapeutic usage are still poorly studied. In this work we present therapeutic benefits of extracts of Achyrocline satureioides, through in vitro and in vivo studies. We evaluated the chemical profiles of the dried extracts, along with antioxidant potential and antimicrobial activity against intestinal pathogenic bacteria. Our data suggest that dried A. satureioides extracts exert greater antibacterial effects than the antibiotic amoxicillin when tested against Bacillus cereus and Staphylococcus aureus. The antioxidant and antimicrobial activities of A. satureioides extracts appear to positively correlate with the amount of flavonoids measured in each extract. Our results provide evidence for the antioxidant and antimicrobial activities of A. satureioides extracts against intestinal pathogens. These findings justify further research regarding the potential for A. satureioides extracts as co-adjuvants to treat bacterial-induced intestinal diseases that may present high rates of antibiotic resistance. Studies regarding the indiscriminate use of plant infusions during pregnancy are limited. Recent reports have shown that chronic flavonoid supplementation induces toxicity in vivo and raises the mortality rates of healthy subjects. Therefore, we investigated whether supplementation of pregnant and lactating Wistar rats with two AS inflorescence extracts, consisting of an aqueous extract similar to a tea (47 mg/kg/day) and a hydroethanolic extract (35 mg/kg/day) with a higher flavonoid content, could induce…

Research paper thumbnail of Chronic acrolein exposure in Wistar rats: The effects of guarana extracts

Journal of Functional Foods, 2019

Previous studies have reported that acrolein, may exert harmful effects on the brain. However, in... more Previous studies have reported that acrolein, may exert harmful effects on the brain. However, information regarding the neuroprotective properties of guarana against acrolein is not available. Due to the lack of research, we initiated the current study to investigate the effects of guarana extracts on acrolein-induced toxicity in the liver and the central nervous system of Wistar Rats. Twelve groups of 60 days old Wistar rats treated with guarana extracts (150, 250, and 350 mg/kg/day) for 8 weeks, were challenged with acrolein (2.5 mg/kg/day). Several parameters associated with oxidative damage to the brain and hepatic function, as well as behavior were evaluated. All tested concentrations of guarana extracts exerted protective effects against acrolein induced damage. No hepatic and oxidative damages or behavioral changes were observed in guarana control groups. To the best of our knowledge, this is the first study of its kind and therefore a milestone in this field.

Research paper thumbnail of Guarana (Paullinia cupanaMart.) alters gut microbiota and modulates redox status, partially via caffeine in Wistar rats

Phytotherapy Research, 2018

Microbiota alterations are observed in pathological conditions, and their regulation is a subject... more Microbiota alterations are observed in pathological conditions, and their regulation is a subject of great interest. Gut microbes are affected by diet, and plant polyphenols may have positive effect on gut microbiota; however, plant-derived extracts may have toxic effects. Guarana (Paullinia cupana Mart.) is a nontraditional medicinal plant applied worldwide. Guarana yields an alkaloid and polyphenol-rich seed with antimicrobial, antioxidant, and anti-inflammatory properties, where caffeine is the major compound. We evaluated the effects of guarana seed powder (GSP) and purified caffeine on gut microbial composition and redox and inflammatory parameters in Wistar rats after 21 days of treatment. Fecal microbiota was analyzed utilizing 16S rDNA sequencing. Antioxidant enzymes activities from liver, kidney, and colon, as well as oxidative damage markers, were evaluated. Total nonenzymatic antioxidant potential was also evaluated. Microbiota was altered by both treatments, GSP and caffeine, without loss of diversity. In the liver, the kidney, and the colon, we observed a decrease in the antioxidant enzymes activities in the GSP group with no increase in the expression of oxidative damage markers, although some enzymes were also regulated by caffeine. Taken together, these results suggested that GSP ameliorates redox parameters but negatively affected gut microbiota, partially via caffeine.

Research paper thumbnail of Anticancer activity of flavonoids isolated from Achyrocline satureioides in gliomas cell lines

Toxicology in vitro : an international journal published in association with BIBRA, 2018

Achyrocline satureioides, popularly known as "marcela", is a medicinal plant found in S... more Achyrocline satureioides, popularly known as "marcela", is a medicinal plant found in South America. This plant is rich in flavonoids, which have been reported to exert numerous biological activities. The aim of this study was to purify, identify and evaluate the mechanisms underlining anticancer activity of A. satureioides flavonoids in glioma cell lines (U87, U251 and C6) as well as their comparative toxicity in normal brain cells (primary astrocytes, neurons and organotypic hippocampal cultures). The main flavonoids present in A. satureioides are luteolin, quercetin, 3-O-methyl-quercetin and achyrobichalcone, the later a very unique metabolite present in this plant. Isolated flavonoids as well as A. satureioides extracts reduced proliferation and clonogenic survival, and induced apoptosis of glioma cell lines. In addition, A. satureioides flavonoids potentiated the cytotoxic effect and apoptosis induction by the glioma chemotherapeutic temozolomide (TMZ). Importantly, A...

Research paper thumbnail of Protective effect of a hydrogel containing Achyrocline satureioides extract-loaded nanoemulsion against UV-induced skin damage

Journal of Photochemistry and Photobiology B: Biology, 2016

Achyrocline satureioides is a medicinal plant widely used in South America that exhibits a well-d... more Achyrocline satureioides is a medicinal plant widely used in South America that exhibits a well-documented antioxidant activity. Such activity has been related to their main aglycone flavonoids quercetin, luteolin, and 3-Omethylquercetin (3MQ). This study addresses the development of antioxidant hydrogels containing an A. satureioides extract-loaded nanoemulsions aimed at topical application. The systems investigated were A. satureioides extract-loaded nanoemulsions (ASNE) obtained by spontaneous emulsification procedure formulated in semisolid hydrogels composed of Carbopol® Ultrez 20 (HASNE). Hydrogels exhibit a non-Newtonian pseudoplastic behavior. A higher release of 3MQ from ASNE (3.61 μg/cm 2 /h) was observed when compared with HASNE (2.83 μg/cm 2 /h). Different parameters that may have an influence on the retention of flavonoids into the skin were investigated by using a Franz-type diffusion cells. Indeed, the amount of formulation applied on donor compartment was found to play a crucial role. At the optimized conditions, retention of approximately 2 μg/cm 2 of flavonoids was detected into the skin. A higher retention of 3MQ was detected (approximately 1.0 μg/ cm 2) in comparison with the other flavonoids. Finally, a protection the porcine ear skin by formulations, against oxidative stress generated by UVA/UVB light was demonstrated by means of TBARS, protein carbonylation, and protein thiol content assays. The overall results showed the potential of the formulations developed in this study for the prevention of oxidative stress on the skin.

Research paper thumbnail of Supplementation with Achyrocline satureioides Inflorescence Extracts to Pregnant and Breastfeeding Rats Induces Tissue-Specific Changes in Enzymatic Activity and Lower Neonatal Survival

Biomedicines, 2017

Achyrocline satureioides (AS, family Asteraceae) is a plant widely used in traditional medicine f... more Achyrocline satureioides (AS, family Asteraceae) is a plant widely used in traditional medicine for stomach, digestive, and gastrointestinal disorders during pregnancy. Studies regarding the indiscriminate use of plant infusions during pregnancy are limited. Recent reports have shown that chronic flavonoid supplementation induces toxicity in vivo and raises the mortality rates of healthy subjects. Therefore, we investigated whether supplementation of pregnant and lactating Wistar rats with two AS inflorescence extracts, consisting of an aqueous (AQ) extract similar to a tea (47 mg•kg −1 •day) and a hydroethanolic (HA) extract (35 mg•kg −1 •day −1) with a higher flavonoid content, could induce redox-related side effects. Total reactive antioxidant potential (TRAP), thiobarbituric reactive species (TBARS), and total reduced thiol (SH) content were evaluated. Superoxide dismutase (SOD) and catalase (CAT) activities were additionally quantified. Our data suggest that both AQ and HA of AS inflorescence extracts may induce symptoms of toxicity in concentrations of (47 mg•kg −1 •day) and (35 mg•kg −1 •day −1), respectively, in mothers regarding the delivery index and further decrease of neonatal survival. Of note, significant tissue-specific changes in maternal (liver, kidney, heart, and hippocampus) and pups (liver and kidney) biochemical oxidative parameters were observed. Our findings provide evidence that may support the need to control supplementation with the AQ of AS inflorescence extracts during gestation due to potential toxicity in vivo, which might be related, at least in part, to changes in tissue-specific redox homeostasis and enzymatic activity.

Research paper thumbnail of Effects of Achyrocline satureioides Inflorescence Extracts against Pathogenic Intestinal Bacteria: Chemical Characterization, In Vitro Tests, and In Vivo Evaluation

Evidence-Based Complementary and Alternative Medicine, 2017

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-drie... more Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared from the aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol). The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17 mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of ...

Research paper thumbnail of Effect of Paullinia cupana Mart. Commercial Extract During the Aging of Middle Age Wistar Rats: Differential Effects on the Hippocampus and Striatum

Neurochemical Research, 2017

treatment (saline, CGE, or caffeine). Solutions were administered daily by oral gavage for 6 mont... more treatment (saline, CGE, or caffeine). Solutions were administered daily by oral gavage for 6 months. Open field and novel object recognition tasks were performed before and after treatment. Biochemical analyses were carried out on the hippocampus and striatum. Our open field data showed an increase in exploratory activity and a decrease in anxiety-like behavior with caffeine but not with the CGE treatment. In the CGE-treated group, catalase activity decreased in the hippocampus and increased in the striatum. Analyses of the hippocampus and striatum indicate that CGE and/ or caffeine altered some of the analyzed parameters in a tissue-specific manner. Our data suggest that CGE intake does not improve cognitive development, but modifies the oxidative stress machinery and neurodegenerative-signaling pathway, inhibiting pro-survival pathway molecules in the hippocampus and striatum. This may contribute to the development of unfavorable microenvironments in the brain and neurodegenerative disorders.

Research paper thumbnail of Changes in bioactive compounds and antioxidant activity of peppers from the Amazon region

Pesquisa Agropecuaria Tropical, Dec 1, 2014

Research paper thumbnail of Effects of different products of peach (Prunus persica L. Batsch) from a variety developed in southern Brazil on oxidative stress and inflammatory parameters in vitro and ex vivo

Journal of Clinical Biochemistry and Nutrition, 2014

Antioxidant, anti glycation and anti inflammatory activities of fresh and conserved peach fruits ... more Antioxidant, anti glycation and anti inflammatory activities of fresh and conserved peach fruits (Prunus persica L. Batsch) were compared. Fresh peach pulps, peels, preserve peach pulps and the preserve syrup were prepared at equal concentrations. Rat liver, kidney and brain cortex tissue slices were pre incubated with peach samples, subjected to oxidative stress with FeSO4 and hydrogen peroxide. Fresh peach pulps and peel conferred higher protection against cytotoxicity and oxidative stress than preserve peach pulps in most tissues. Release of tumor necrosis factor α and interleukin 1β was also significantly decreased by Fresh peach pulps and peel, followed by preserve peach pulps. Total phenolic determination and HPLC analysis of carotenoids showed that the content of secondary metabolites in Fresh peach pulps and peel is signifi cantly higher than in preserve peach pulps, while the syrup had only small or trace amounts of these compounds. Fresh peach pulps and Peel demonstrated high antioxidant and anti inflammatory effects preventing against induced damage.

Research paper thumbnail of Preventive supplementation with fresh and preserved peach attenuates CCl4-induced oxidative stress, inflammation and tissue damage

The Journal of Nutritional Biochemistry, 2014

The present study was elaborated to comparatively evaluate the preventive effect of different pea... more The present study was elaborated to comparatively evaluate the preventive effect of different peach-derived products obtained from preserved fruits (Syrup and Preserve Pulp Peach [PPP]) and from fresh peels and pulps (Peel and Fresh Pulp Peach [FPP]) in a model of liver/renal toxicity and inflammation induced by carbon tetrachloride (CCl 4) in rats. Tissue damage (carbonyl, thiobarbituric acid reactive species and sulfhydril), antioxidant enzymes activity (catalase and superoxide dismutase) and inflammatory parameters [tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels, and receptor for advanced glycation endproducts (RAGE) and nuclear factor (NF)κB-p65 immunocontent] were investigated. Our findings demonstrated that Peel, PPP and FPP (200 or 400 mg/kg) daily administration by oral gavage for 30 days conferred a significant protection against CCl 4-induced antioxidant enzymes activation and, most importantly, oxidative damage to lipids and proteins as well as blocked induction of inflammatory mediators such as TNF-α, IL-1β, RAGE and NFκB. This antioxidant/antiinflammatory effect seems to be associated with the abundance of carotenoids and polyphenols present in peach-derived products, which are enriched in freshfruit-derived preparations (Peel and FPP) but are also present in PPP. The Syrupwhich was the least enriched in antioxidantsdisplayed no protective effect in our experiments. These effects cumulated in decreased levels of transaminases and lactate dehydrogenase leakage into serum and maintenance of organ architecture. Therefore, the herein presented results show evidence that supplementation with peach products may be protective against organ damage caused by oxidative stress, being interesting candidates for production of antioxidant-enriched functional foods.

Research paper thumbnail of 1170-P: Long-Term Effects of Lifestyle Changes in Subjects with Prediabetes and Type 2 Diabetes on Cardiovascular and All-Cause Mortality: A Systematic Review with Meta-analysis of Randomized Clinical Trials

Diabetes

Long-term RCTs have shown that lifestyle interventions (LI) can prevent T2DM in individuals with ... more Long-term RCTs have shown that lifestyle interventions (LI) can prevent T2DM in individuals with prediabetes, improve glycemic control in individuals with T2DM, as well as improve lipid profile and lower blood pressure in both. However, the impact of these interventions on cardiovascular (CV) and total mortality is still not clear. Therefore, we conducted a systematic review with meta-analysis to determine the long-term efficacy of LI on CV and all-cause mortality in subjects with prediabetes and T2DM. We searched PubMed, Cochrane CENTRAL, Embase, Web of Science, protocol records, and reference lists of relevant publications until December 2021. We selected RCTs including adults with prediabetes and T2DM that evaluated LI with at least 2 years of duration, with or without post-trial follow-up. The main outcomes consisted of CV and all-cause mortality. We used the RoB 2.0 tool to evaluate the risk of bias and the GRADE approach for the overall certainty of evidence. Meta-analysis was...

Research paper thumbnail of DELAYED NEUROCHEMICAL EFFECTS OF PRENATAL EXPOSURE TO MeHg IN THE CEREBELLUM OF DEVELOPING RATS

Toxicology letters, Jan 16, 2017

Human fetuses and neonates are particularly vulnerable to methylmercury (MeHg)-induced brain dama... more Human fetuses and neonates are particularly vulnerable to methylmercury (MeHg)-induced brain damage and are sensitive even to low exposure levels. Previous work of our group evidence that prenatal exposure to MeHg causes cognitive and behavioral alterations and disrupt hippocampus signaling. The current study aimed to investigate the effect of gestational exposure of rats to MeHg at low doses (1 or 2 mg/Kg) on parameters of redox imbalance and key signaling pathways in the cerebellum of their offspring. Pregnant females received MeHg (treated group) or 0.9% saline water (control group) by gavage in alternated days from gestational day 5 (GD5) until parturition and analyzes were proceed in the cerebellum of 30-day-old pups. We found increased lipid peroxidation and protein carbonylation levels as well as decreased SH content in pups prenatally exposed to 2 mg/kg MeHg. In addition, misregulated SOD/catalase activities supported imbalanced redox equilibrium. We found decreased GSK3β(Se...

Research paper thumbnail of Desenvolvimento de nanocápsula de extrato de Achyrocline Satureioides (Marcela) como adjuvante no tratamento da diabetes

Research paper thumbnail of Characterization of a novel antioxidant peptide from feather keratin hydrolysates

New biotechnology, Jan 14, 2018

Feather hydrolysates were obtained through submerged cultivation of 50 g/L feathers with Chryseob... more Feather hydrolysates were obtained through submerged cultivation of 50 g/L feathers with Chryseobacterium sp. kr6. Culture supernatants, displaying antioxidant properties, as evaluated by the 2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid (ABTS) radical scavenging method, were partially purified by gel-filtration chromatography. Fractions showing scavenging activity were pooled, lyophilized and tested at different concentrations (0.1-1.0 mg/mL) by the total reactive antioxidant potential (TRAP) method, showing promising antioxidant capacities. Antioxidant activities of the partially purified feather hydrolysate (PPFH; 24.5 μg) were demonstrated by its ability to scavenge hydroxyl radicals and to inhibit lipid peroxidation. In addition, PPFH (0.24-24.5 μg) was found to reduce ferric ion (Fe), but did not display Fe-chelating activity. Thus, the main antioxidant activities could be related to the donation of hydrogen atoms, electron transfer and scavenging of hydroxyl rad...