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Papers by Yandara Akamine Martins

Chemico-Biological Interactions, Oct 1, 2022

Many foods contain mixtures of plant dietary proteins and polyphenols, but there is currently a r... more Many foods contain mixtures of plant dietary proteins and polyphenols, but there is currently a relatively poor understanding of the nature of the interactions between these components. In this study, the interaction of rice glutelin (RG) and gallic acid (GA) was characterized by spectroscopic and molecular docking techniques. The intrinsic fluorescence of RG quenched after the addition of GA, indicating that an interaction occurred. Thermodynamic analyses indicated that the binding process was spontaneous and the main driving forces were hydrogen bonds and van der Waals. The surface hydrophobicity of RG decreased with increasing GA. Furthermore, synchronous fluorescence and circular dichroism spectra provided insights into micro-environmental and conformational changes of RG. In particular, there was a reduction of α-helix structure and an increase of β-sheet structure present in RG after the binding interaction. Finally, molecular docking analysis provided a visual representation of a single binding site where GA interacted with specific amino acid residues located in the active site of the RG.

Journal of Alzheimer's disease reports, Dec 2, 2017

Background: Alzheimer's disease (AD) is a neurodegenerative disease that does not have a proven c... more Background: Alzheimer's disease (AD) is a neurodegenerative disease that does not have a proven cure; however, one of the most promising strategies for its treatment has been DNA vaccines. Objective: The present review is aimed to report the new developments of the efficacy and safety of DNA vaccines for AD in animal models. Method: The method PRISMA was used for this review. The article search was made in the electronic databases PubMed, LILACS, and Scopus using the descriptors ''Alzheimer disease" and ''Vaccine, DNA". Articles published between January 2001 and September 2017 in English, Portuguese, and Spanish were included. Results: Upon the consensus, the researchers identified 28 original articles. The studies showed satisfying results as for the decrease of amyloid plaques in mouse, rabbits, and monkeys brains using mostly the DNA A␤ 42 vaccine, AV-1955, and AdPEDI-(A␤1-6)11, mainly with a gene gun. In addition to a reduction in tau by the first DNA vaccine (AV-1980D) targeting this protein. The use of adjuvants and boosters also had positive results as they increased the destruction of the amyloid plaques and induced an anti-inflammatory response profile without side effects. Conclusion: The results of DNA vaccines targeting the amyloid-␤ and the tau protein with or without adjuvants and boosters were promising in reducing amyloid plaques and tau protein without side effects in animals. Although there are many vaccines being tested in animals, few reach clinical trials. Thus, as a future perspective, we suggest that clinical studies should be conducted with vaccines that have been promising in animal models (e.g., DNA A␤ 42 vaccine, AV-1955, and AdPEDI-(A␤1-6)11).

Drugs & Aging, Aug 3, 2021

Around two-thirds of patients with Alzheimer’s disease (AD) are women, which could be related to ... more Around two-thirds of patients with Alzheimer’s disease (AD) are women, which could be related to the depletion of female sexual hormones at menopause. The replacement of these hormones with hormone therapy (HT) to possibly decrease AD risk or treat AD patients has generated conflicting results in the literature. Our aim was to systematically review the relationship between HT use in postmenopausal women with AD and the risk of developing or treating AD symptoms. The PubMed, LILACS, Scopus, Scielo, and Web of Science databases were searched from January 1994 to December 2020 using the descriptors ‘Alzheimer Disease OR Alzheimer’s Disease’ and ‘Hormone Replacement Therapy OR Estrogen Replacement Therapy’. Observational and controlled clinical trials including postmenopausal women diagnosed with AD and evaluating HT efficacy were eligible for inclusion. Extracted data comprise study design, covariates, inclusion criteria for sample selection, AD diagnosis criteria, biases, HT regimen, and cognitive measurement tools used. Overall, 25 studies were selected. Among the 14 observational studies, 8 reported an improvement in cognitive function and a decrease in AD risk, especially in younger postmenopausal women. Five observational studies did not demonstrate any association between HT and AD, and one study reported an increase in AD risk, regardless of time of HT initiation. Of the 11 controlled clinical trials included, 7 showed an amelioration in cognitive function after HT. The remaining 4 trials saw no difference between HT and control. Both observational and controlled clinical trials had methodological issues and discrepancies in inclusion criteria and HT protocols. These inconsistencies made it difficult to establish an association between HT and AD.

Chemico-Biological Interactions, 2021

The interaction of the steviol and its glycosides (SG), steviolbioside, and rebaudioside A, with ... more The interaction of the steviol and its glycosides (SG), steviolbioside, and rebaudioside A, with bovine serum albumin (BSA) was studied by absorption and fluorescence spectroscopy techniques alongside molecular docking. The stevia derivatives quenched the fluorescence of BSA by a dynamic quenching mechanism, indicating the interaction between the stevia derivatives and BSA. The binding constant (Kb) of steviol was 100-1000-fold higher than those of SG. The stevia derivative/BSA binding reaction was spontaneous and involved the formation of hydrogen bonds and van der Waals interactions between steviol and steviolbioside with BSA, and water reorganization around the rebaudioside A/BSA complex. Molecular docking pointed out the FA1 and FA9 binding sites of BSA as the probable binding sites of steviol and SG, respectively. In conclusion, steviol enhanced hydrophobicity and small size compared to SG may favor its binding to BSA. As steviol and its glycosides share binding sites on BSA with free fatty acids and drugs, they may be competitively displaced from plasma albumin under various physiological states or disease conditions. These findings are clinically relevant and provide an insight into the pharmacokinetics and pharmacodynamics of the stevia glycosides.

Nutrition Reviews, 2019

Context Recent findings have suggested a high prevalence of vitamin D deficiency or insufficiency... more Context Recent findings have suggested a high prevalence of vitamin D deficiency or insufficiency in fibromyalgia (FM) patients despite the lack of clinical and pathophysiological evidence. Objective A systematic review was conducted to examine the association between vitamin D status and FM, including the effect of vitamin D supplementation. Data source PubMed, LILACS, Scopus, SciELO, Cochrane, and EMBASE were searched, from January 2000 to July 2018, using the descriptors “Fibromyalgia” and “Vitamin D.” Study selection Trials including FM patients in whom vitamin D levels were assessed were eligible for inclusion. Data extraction Data comprised age, gender, country, aims, bias, diagnosis criteria, cutoff point, and status of vitamin D, together with FM symptoms and vitamin D supplementation protocol. Results A total of 26 articles were selected. Most of the studies were found to present unreliable control groups and small samples. Experimental data on vitamin D supplementation ind...