Rosaria Acquaviva | University of Catania (original) (raw)

Papers by Rosaria Acquaviva

PloS one, 2015

Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is widely used in traditional medicine. There... more Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is widely used in traditional medicine. There is increasing interest on the in vivo protective effects of natural compounds contained in plants against oxidative damage caused from reactive oxygen species. In the present study the total phenolic and flavonoid contents of aqueous, methanol and dichloromethane extracts of leaves of Tithonia diversifolia (Hemsl.) A. Gray were determined; furthermore, free radical scavenging capacity of each extract and the ability of these extracts to inhibit in vitro plasma lipid peroxidation were also evaluated. Since oxidative stress may be involved in trasformation of pre-adipocytes into adipocytes, to test the hypothesis that Tithonia extract may also affect adipocyte differentiation, human mesenchymal stem cell cultures were treated with Tithonia diversifolia aqueous extract and cell viability, free radical levels, Oil-Red O staining and western bolt analysis for heme oxygenase and 5'-adenos...

Biochemical and molecular medicine, 1997

Considerable evidence indicates that reactive oxygen species play an etiological role in both car... more Considerable evidence indicates that reactive oxygen species play an etiological role in both cardiotoxicity and the skin necrosis induced by adriamycin (ADM). An increase in glutathione peroxidase activity on addition of selenium to cultured MCR-5 lung fibroblasts was observed; this increase was accompanied by enhanced cellular resistance to ADM toxicity. Moreover, the presence of exogenous antioxidant systems, such as superoxide dismutase, catalase, vitamin E, dimethylsulfoxide, and desferroxamine, an iron chelating agent, resulted in significant protection from ADM-mediated damage.

Current neurovascular research, 2005

Several lines of evidence have extensively demonstrated that peroxynitrite plays a pivotal role i... more Several lines of evidence have extensively demonstrated that peroxynitrite plays a pivotal role in Central Nervous System (CNS) injuries. The present study was aimed at elucidating the molecular mechanism by which propofol attenuates peroxynitrite-mediated injury in the brain. Primary cultured astroglial cells were incubated for 18 h with a known peroxynitrite donor (SIN-1,3 mM) in the presence or absence of propofol (40 microM, 80 microM and 160 microM). The protective effects of propofol were evaluated by MTT cytotoxicity assay, LDH release, and caspase-3 activation by Western blot analysis. Appropriate propofol concentrations (ranging from 40 microM to 160 microM) significantly increased HO-1 expression and attenuated SIN-1-mediated cytotoxicity and caspase-3 activation. The protective effects of propofol were mitigated by the addition of tin-mesoporphirin (SnMP), a potent inhibitor of HO activity. The addition of a specific synthetic inhibitor of NF-kappaB abolished propofol-med...

Cell biology and toxicology, 2000

L-Propionylcarnitine, a propionyl ester of L-carnitine, increases the intracellular pool of L-car... more L-Propionylcarnitine, a propionyl ester of L-carnitine, increases the intracellular pool of L-carnitine. It exhibits a high affinity for the enzyme carnitine acetyltransferase (CAT) and, thus, is readily converted into propionyl-coenzyme A and free carnitine. It has been reported that L-propionylcarnitine possesses a protective action against heart ischemia-reperfusion injury; however, the antioxidant mechanism is not yet clear. L-Propionylcarnitine might reduce the hydroxyl radical production in the Fenton system, by chelating the iron required for the generation of hydroxyl radicals. To obtain a better insight into the antiradical mechanism of L-propionylcarnitine, the present research analyzed the superoxide scavenging capacity of L-propionylcarnitine and its effect on linoleic acid peroxidation. In addition, the effect of L-propionylcarnitine against DNA cleavage was estimated using pBR322 plasmid. We found that L-propionylcarnitine showed a dose-dependent free-radical scavengin...

Cell biology and toxicology, 2000

Flavonoids have recently aroused considerable interest because of their broad pharmacological act... more Flavonoids have recently aroused considerable interest because of their broad pharmacological activity. In fact, flavonoids have been reported to have antiviral, antiallergic, antiplatelet, anti-inflammatory and antitumoral activities. The pharmacological properties of bioflavonoids have been ascribed both to the concomitant inhibition of enzymes involved in the production of free radicals and to their free-radical scavenging and iron chelating capacity. However the antioxidant capacity of bioflavonoids due to free-radical scavenging and/or to iron chelating is still controversial. In this study, we have investigated the free-radical scavenging capacity of bioflavonoids (rutin, catechin, and naringin). In addition, the effects of these polyphenols on xanthine oxidase activity, spontaneous lipid peroxidation, and DNA cleavage were investigated. The bioflavonoids under examination showed a dose-dependent free-radical scavenging effect, a significant inhibition of xanthine oxidase acti...

Nitric oxide (NO) plays a key role in the relationship between microcirculatory disorders and I/R... more Nitric oxide (NO) plays a key role in the relationship between microcirculatory disorders and I/R injuries. Our results demonstrated a significant modification in the hepatic function of I/R rats compared with the control group; treatment with rutin reported hepatic damage markers to control value. Levels of plasmatic and hepatic thiol groups decreased in the I/R untreated group, and this decrease was inhibited by rutin treatment. In addition, we observed an increase in the iNOS expression in I/R group compared with control and rutin administration attenuated this increase; in post-ischemic reperfused rutin-treated rats there was a significant increase in eNOS expression compared with the I/R untreated group. In the same experimental conditions an increase in DDAH 1 expression was observed in I/R group only; rutin treatment also counteracted this increased expression. These data suggest that rutin treatment could be useful for preventing oxidative damage associated with hepatic post-ischemic reperfusion injury.

Journal of medicinal food, 2009

Aerobic exercise increases free radical production as a consequence of enhanced oxygen consumptio... more Aerobic exercise increases free radical production as a consequence of enhanced oxygen consumption. If free radical formation exceeds antioxidant capacity, lipids, proteins, and DNA may be oxidized. Oxidative stress is widely recognized as a factor in many degenerative human diseases. The role of dietary antioxidants in protection against disease is a topic of continuing interest. In fact, there is epidemiological evidence correlating a higher intake of nutrients possessing antioxidant abilities with a lower incidence of various human diseases. This study was directed at investigating whether changes in plasma antioxidant capacity and oxidative stress markers occur in voluntary wheel runners, before and after oral supplementation with lycopene and isoflavones. For this purpose, plasma antioxidant capacity and oxidative stress markers were assessed in long distance runners at the end of a 60-minute run. Comparisons were made between runners before and after 60 days of supplementation...

Cell Biology and Toxicology, 2003

Anthocyanins, colored flavonoids, are water-soluble pigments present in the plant kingdom; in fac... more Anthocyanins, colored flavonoids, are water-soluble pigments present in the plant kingdom; in fact they are secondary plant metabolites responsible for the blue, purple, and red color of many plant tissues. Present in beans, fruits, vegetables and red wines, considerable amounts of anthocyanins are ingested as constituents of the human diet (180–215 mg daily). There is now increasing interest in thein

Molecular Nutrition and Food Research, 2007

The aim of the present research was to investigate the effect of cyanidin-3-O-b-glucoside (C3G) o... more The aim of the present research was to investigate the effect of cyanidin-3-O-b-glucoside (C3G) on heme oxygenase-1 (HO-1), endothelial nitric oxide synthase (eNOS), inducible NOS (iNOS) and dimethylarginine dimethylamino hydrolase-2 (DDAH-2) expression in cultured endothelial cells. Different concentrations (0.00625 -250 lM) of C3G were tested in order to investigate possible beneficial and harmful effects of C3G. Our data demonstrated that C3G increased the induction of eNOS and HO-1 in a dose-dependent manner. Higher concentration (62.5 -250 lM) also resulted in increase of isoprostane, cGMP and PGE 2 levels and in induction of iNOS with consequent oxidative stress. In conclusion, our data evidence that C3G may exert various protective effects against endothelial dysfunction, whereas potentially harmful effects of C3G appear to be limited to concentrations very difficult to be reached in physiological conditions unless there is abundant oral supplementation.

International Journal of Oncology, 2012

Currently, there is increasing interest in the in vivo protective effects of natural antioxidants... more Currently, there is increasing interest in the in vivo protective effects of natural antioxidants found in dietary plants against oxidative damage caused by free radical species. Oxidative stress has been invoked as a causative agent in cancer and epidemiological data suggest that the consumption of fruits and vegetables may be associated with a lower incidence of cancer. The fruit of the Olea europaea L. and olive oil contain hundreds of phytochemicals and its extracts have recently been shown to exhibit antioxidant properties, due to the action of oleuropein. In view of these considerations, in this study, we investigated the effects of oleuropein on LNCaP and DU145 prostate cancer cell lines and on BPH-1 non-malignant cells. Oleuropein reduces cell viability and induces thiol group modifications, γ-glutamylcysteine synthetase, reactive oxygen species, pAkt and heme oxygenase-1. Exposing cell cultures to oleuropein induces an antioxidant effect on BPH-1 cells and a pro-oxidant effect on cancer cells. Our results confirm the beneficial properties of olive oil and oleuropein, suggesting its possible use as an adjuvant agent in the treatment of prostatitis, in order to prevent the transformation of hypertrophic to cancerous cells.

Toxins, 2013

Ochratoxin A (OTA) is a mycotoxin involved in the development of different types of cancers in ra... more Ochratoxin A (OTA) is a mycotoxin involved in the development of different types of cancers in rats, mice and humans. A growing number of in vitro and in vivo studies has been collected and has described evidence compatible with a role for oxidative stress in OTA toxicity and carcinogenicity. Because the contribution of the oxidative stress response in the development of cancers is well established, a role in OTA carcinogenicity is plausible. Several studies have been performed to try to counteract the adverse effects of oxygen radicals generated under OTA-exposure. A number of molecules with various antioxidant properties were tested, using in vivo or in vitro models. Protection against OTA-induced DNA damage, lipid peroxidation, as well as cytotoxicity were observed, further confirming the link between OTA toxicity and oxidative damage. These studies demonstrated that antioxidants are able to counteract the deleterious effects of chronic consumption or exposure to OTA and confirmed the potential effectiveness of dietary strategies to counteract OTA toxicity.

Transplantation Proceedings, 2007

Nitric oxide (NO), produced by nitric oxide synthase, is implicated in the pathophysiology of ren... more Nitric oxide (NO), produced by nitric oxide synthase, is implicated in the pathophysiology of renal ischemia/reperfusion (I/R) injury. This study sought to elucidate the impact of pharmacological induction of heme oxygenase-1 (HO-1) on renal I/R injury. Rats were subjected to 45 minutes of renal ischemia followed by various times of reperfusion (30 minutes, 1 hour, or 3 hours). Plasma from sacrificed rats was obtained, and the kidneys processed for the expression of iNOS, cleaved caspase-3, p38MAPK and for immunohistochemical analysis. Furthermore, we determined renal and plasma levels of lipid hydroperoxides, total thiol groups, and plasmatic NO 2 Ϫ /NO 3 Ϫ formation. Our results showed a time-dependent increase in iNOS expression, which was also confirmed by increased plasma formation of NO 2 Ϫ /NO 3 Ϫ . Interestingly, this effect was reversed by pretreatment (12 hours) with SnCl 2 , a potent and specific inducer of renal HO-1 expression and activity, or by intraperitoneal injection of biliverdin (10 mg/kg). Furthermore, we observed a concomitant reduction in plasma and renal LOOH formation, a normalization of renal total thiol content, a reduction of caspase-3-mediated apoptosis, and a significant increase in p38MAPK phosphoration. Taken together, these results suggested that HO-1 and its byproduct biliverdin play major roles in the pathophysiological cascade leading to renal I/R injury.

Phytotherapy Research, 2011

Berberis aetnensis C. Presl. is a bushy-spiny shrub common on Mount Etna (Sicily, Italy), contain... more Berberis aetnensis C. Presl. is a bushy-spiny shrub common on Mount Etna (Sicily, Italy), containing various alkaloids with several pharmacological properties. This study assessed the effect of berberine and of the alkaloid extract of B. aetnensis roots on the glutamate-evoked tissue transglutaminase (TG2) up-regulation in rat astrocyte primary cultures, used as an in vitro model of excitotoxicity. The findings show that the alkaloid extract of B. aetnensis roots consists mainly of berberine. Furthermore, berberine and the alkaloid extract of B. aetnensis roots were able to restore the oxidative status modified by glutamate and the levels of TG2 to control values. It was found that berberine or the alkaloid extract of B. aetnensis roots are able to ameliorate the excessive production of glutamate, protein misfolding and aggregation, mitochondrial fragmentation, and neurodegeneration. Thus, it is suggested that berberine and the alkaloid extract of B. aetnensis roots, may represent a natural therapeutic strategy in the neuropathological conditions associated with excitotoxicity.

Nitric Oxide, 2006

The reperfusion of ischemic tissue often delays its physiological and functional recovery; this p... more The reperfusion of ischemic tissue often delays its physiological and functional recovery; this paradoxical effect is ascribed to increased release of free radicals including O 2 ÅÀ and NO. For these reasons, scavenging reactive oxygen species or inhibition the NO synthesis has been shown to result in an enhanced neuronal survival after cerebral ischemia. Many authors believe that therapy for stroke patients would be a cocktail of drugs with various mechanisms of action. Combination therapy is a difficult and complicated avenue for drug development because of the possibility of drug-drug interactions. An alternative approach would be to combine multiple activities within the same compound. In consideration of the free-radical scavenging and inhibitory effect on NOS of various natural and synthetic compounds, the aim of this study was to analyze the antioxidant properties of some imidazole derivatives previously synthesized in our laboratory. Results obtained in the present study provide evidence that tested compounds exhibit interesting antioxidant properties, expressed either by their capacity to scavenge free radicals or their ability to reduce lipid peroxidation. In particular, compounds A and B represent chemical structures which can be easily modified to improve the observed antioxidant properties and to provide new therapeutic strategies focused on multiple downstream events.

Neuroscience Letters, 2010

The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields ... more The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields (EMF) in the microwave range was studied. Differentiated astroglial cell cultures at 14 days in vitro were exposed for 5, 10, or 20min to either 900MHz continuous waves or 900MHz waves modulated in amplitude at 50Hz using a sinusoidal waveform and 100% modulation index. The strength of the electric field (rms value) at the sample position was 10V/m. No change in cellular viability evaluated by MTT test and lactate dehydrogenase release was observed. A significant increase in ROS levels and DNA fragmentation was found only after exposure of the astrocytes to modulated EMF for 20min. No evident effects were detected when shorter time intervals or continuous waves were used. The irradiation conditions allowed the exclusion of any possible thermal effect. Our data demonstrate, for the first time, that even acute exposure to low intensity EMF induces ROS production and DNA fragmentation in astrocytes in primary cultures, which also represent the principal target of modulated EMF. Our findings also suggest the hypothesis that the effects could be due to hyperstimulation of the glutamate receptors, which play a crucial role in acute and chronic brain damage. Furthermore, the results show the importance of the amplitude modulation in the interaction between EMF and neocortical astrocytes.

Molecules, 2013

Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils,... more Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils, found in swampy areas in Central Uganda. Antidiabetic and antilipogenic activities were reported for some Momordica species, however the mechanism of action is still unknown. Oxidative stress may represent an important pathogenic mechanism in obesity-associated metabolic syndrome. The present study evaluated free radical scavenging capacity of different concentrations of aqueous, methanolic and dichloromethane leaf extracts of Momordica foetida Schumach. et Thonn. and the ability of these extracts to inhibit in vitro plasma lipid peroxidation; in addition, healthy human adipose mesenchymal stem cell cultures were used in order to test the hypothesis that these extracts may affect adipocyte differentiation. Results obtained in this study suggested that aqueous extract might be useful in preventing metabolic syndrome.

Microsurgery, 2006

Ischemia/reperfusion (I/R) injury is a multifactorial process that affects liver function after t... more Ischemia/reperfusion (I/R) injury is a multifactorial process that affects liver function after transplantation and resectional surgery. Alterations in hepatic microcirculation and decreased hepatic flow can cause local hypoxia and consequently liver damage, which is worsened by reperfusion. The aim of this study was to evaluate if treatment with L-arginine improved hepatic function in rats with I/R injury. Animals were treated with L-arginine, ischemized for 30 min, and reperfused for 3 h. Plasmatic levels of GOT, GPT, lipid hydroperoxides (LOOH), and total thiol groups (RSH) were evaluated. In addition, we analyzed hepatic LOOH and RSH levels, DNA fragmentation, heme oxygenase 1 (HO-1) expression, and histological modifications. Our results demonstrate a significant improvement in hepatic function of I/R rats compared to the control group. Treatment with L-arginine increased the expression of HO-1. These data suggest that L-arginine could be useful in preventing oxidative damage during hepatic surgery. ª 2006 Wiley-Liss, Inc. Microsurgery 26: 25À32, 2006.

PloS one, 2015

Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is widely used in traditional medicine. There... more Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is widely used in traditional medicine. There is increasing interest on the in vivo protective effects of natural compounds contained in plants against oxidative damage caused from reactive oxygen species. In the present study the total phenolic and flavonoid contents of aqueous, methanol and dichloromethane extracts of leaves of Tithonia diversifolia (Hemsl.) A. Gray were determined; furthermore, free radical scavenging capacity of each extract and the ability of these extracts to inhibit in vitro plasma lipid peroxidation were also evaluated. Since oxidative stress may be involved in trasformation of pre-adipocytes into adipocytes, to test the hypothesis that Tithonia extract may also affect adipocyte differentiation, human mesenchymal stem cell cultures were treated with Tithonia diversifolia aqueous extract and cell viability, free radical levels, Oil-Red O staining and western bolt analysis for heme oxygenase and 5'-adenos...

Biochemical and molecular medicine, 1997

Considerable evidence indicates that reactive oxygen species play an etiological role in both car... more Considerable evidence indicates that reactive oxygen species play an etiological role in both cardiotoxicity and the skin necrosis induced by adriamycin (ADM). An increase in glutathione peroxidase activity on addition of selenium to cultured MCR-5 lung fibroblasts was observed; this increase was accompanied by enhanced cellular resistance to ADM toxicity. Moreover, the presence of exogenous antioxidant systems, such as superoxide dismutase, catalase, vitamin E, dimethylsulfoxide, and desferroxamine, an iron chelating agent, resulted in significant protection from ADM-mediated damage.

Current neurovascular research, 2005

Several lines of evidence have extensively demonstrated that peroxynitrite plays a pivotal role i... more Several lines of evidence have extensively demonstrated that peroxynitrite plays a pivotal role in Central Nervous System (CNS) injuries. The present study was aimed at elucidating the molecular mechanism by which propofol attenuates peroxynitrite-mediated injury in the brain. Primary cultured astroglial cells were incubated for 18 h with a known peroxynitrite donor (SIN-1,3 mM) in the presence or absence of propofol (40 microM, 80 microM and 160 microM). The protective effects of propofol were evaluated by MTT cytotoxicity assay, LDH release, and caspase-3 activation by Western blot analysis. Appropriate propofol concentrations (ranging from 40 microM to 160 microM) significantly increased HO-1 expression and attenuated SIN-1-mediated cytotoxicity and caspase-3 activation. The protective effects of propofol were mitigated by the addition of tin-mesoporphirin (SnMP), a potent inhibitor of HO activity. The addition of a specific synthetic inhibitor of NF-kappaB abolished propofol-med...

Cell biology and toxicology, 2000

L-Propionylcarnitine, a propionyl ester of L-carnitine, increases the intracellular pool of L-car... more L-Propionylcarnitine, a propionyl ester of L-carnitine, increases the intracellular pool of L-carnitine. It exhibits a high affinity for the enzyme carnitine acetyltransferase (CAT) and, thus, is readily converted into propionyl-coenzyme A and free carnitine. It has been reported that L-propionylcarnitine possesses a protective action against heart ischemia-reperfusion injury; however, the antioxidant mechanism is not yet clear. L-Propionylcarnitine might reduce the hydroxyl radical production in the Fenton system, by chelating the iron required for the generation of hydroxyl radicals. To obtain a better insight into the antiradical mechanism of L-propionylcarnitine, the present research analyzed the superoxide scavenging capacity of L-propionylcarnitine and its effect on linoleic acid peroxidation. In addition, the effect of L-propionylcarnitine against DNA cleavage was estimated using pBR322 plasmid. We found that L-propionylcarnitine showed a dose-dependent free-radical scavengin...

Cell biology and toxicology, 2000

Flavonoids have recently aroused considerable interest because of their broad pharmacological act... more Flavonoids have recently aroused considerable interest because of their broad pharmacological activity. In fact, flavonoids have been reported to have antiviral, antiallergic, antiplatelet, anti-inflammatory and antitumoral activities. The pharmacological properties of bioflavonoids have been ascribed both to the concomitant inhibition of enzymes involved in the production of free radicals and to their free-radical scavenging and iron chelating capacity. However the antioxidant capacity of bioflavonoids due to free-radical scavenging and/or to iron chelating is still controversial. In this study, we have investigated the free-radical scavenging capacity of bioflavonoids (rutin, catechin, and naringin). In addition, the effects of these polyphenols on xanthine oxidase activity, spontaneous lipid peroxidation, and DNA cleavage were investigated. The bioflavonoids under examination showed a dose-dependent free-radical scavenging effect, a significant inhibition of xanthine oxidase acti...

Nitric oxide (NO) plays a key role in the relationship between microcirculatory disorders and I/R... more Nitric oxide (NO) plays a key role in the relationship between microcirculatory disorders and I/R injuries. Our results demonstrated a significant modification in the hepatic function of I/R rats compared with the control group; treatment with rutin reported hepatic damage markers to control value. Levels of plasmatic and hepatic thiol groups decreased in the I/R untreated group, and this decrease was inhibited by rutin treatment. In addition, we observed an increase in the iNOS expression in I/R group compared with control and rutin administration attenuated this increase; in post-ischemic reperfused rutin-treated rats there was a significant increase in eNOS expression compared with the I/R untreated group. In the same experimental conditions an increase in DDAH 1 expression was observed in I/R group only; rutin treatment also counteracted this increased expression. These data suggest that rutin treatment could be useful for preventing oxidative damage associated with hepatic post-ischemic reperfusion injury.

Journal of medicinal food, 2009

Aerobic exercise increases free radical production as a consequence of enhanced oxygen consumptio... more Aerobic exercise increases free radical production as a consequence of enhanced oxygen consumption. If free radical formation exceeds antioxidant capacity, lipids, proteins, and DNA may be oxidized. Oxidative stress is widely recognized as a factor in many degenerative human diseases. The role of dietary antioxidants in protection against disease is a topic of continuing interest. In fact, there is epidemiological evidence correlating a higher intake of nutrients possessing antioxidant abilities with a lower incidence of various human diseases. This study was directed at investigating whether changes in plasma antioxidant capacity and oxidative stress markers occur in voluntary wheel runners, before and after oral supplementation with lycopene and isoflavones. For this purpose, plasma antioxidant capacity and oxidative stress markers were assessed in long distance runners at the end of a 60-minute run. Comparisons were made between runners before and after 60 days of supplementation...

Cell Biology and Toxicology, 2003

Anthocyanins, colored flavonoids, are water-soluble pigments present in the plant kingdom; in fac... more Anthocyanins, colored flavonoids, are water-soluble pigments present in the plant kingdom; in fact they are secondary plant metabolites responsible for the blue, purple, and red color of many plant tissues. Present in beans, fruits, vegetables and red wines, considerable amounts of anthocyanins are ingested as constituents of the human diet (180–215 mg daily). There is now increasing interest in thein

Molecular Nutrition and Food Research, 2007

The aim of the present research was to investigate the effect of cyanidin-3-O-b-glucoside (C3G) o... more The aim of the present research was to investigate the effect of cyanidin-3-O-b-glucoside (C3G) on heme oxygenase-1 (HO-1), endothelial nitric oxide synthase (eNOS), inducible NOS (iNOS) and dimethylarginine dimethylamino hydrolase-2 (DDAH-2) expression in cultured endothelial cells. Different concentrations (0.00625 -250 lM) of C3G were tested in order to investigate possible beneficial and harmful effects of C3G. Our data demonstrated that C3G increased the induction of eNOS and HO-1 in a dose-dependent manner. Higher concentration (62.5 -250 lM) also resulted in increase of isoprostane, cGMP and PGE 2 levels and in induction of iNOS with consequent oxidative stress. In conclusion, our data evidence that C3G may exert various protective effects against endothelial dysfunction, whereas potentially harmful effects of C3G appear to be limited to concentrations very difficult to be reached in physiological conditions unless there is abundant oral supplementation.

International Journal of Oncology, 2012

Currently, there is increasing interest in the in vivo protective effects of natural antioxidants... more Currently, there is increasing interest in the in vivo protective effects of natural antioxidants found in dietary plants against oxidative damage caused by free radical species. Oxidative stress has been invoked as a causative agent in cancer and epidemiological data suggest that the consumption of fruits and vegetables may be associated with a lower incidence of cancer. The fruit of the Olea europaea L. and olive oil contain hundreds of phytochemicals and its extracts have recently been shown to exhibit antioxidant properties, due to the action of oleuropein. In view of these considerations, in this study, we investigated the effects of oleuropein on LNCaP and DU145 prostate cancer cell lines and on BPH-1 non-malignant cells. Oleuropein reduces cell viability and induces thiol group modifications, γ-glutamylcysteine synthetase, reactive oxygen species, pAkt and heme oxygenase-1. Exposing cell cultures to oleuropein induces an antioxidant effect on BPH-1 cells and a pro-oxidant effect on cancer cells. Our results confirm the beneficial properties of olive oil and oleuropein, suggesting its possible use as an adjuvant agent in the treatment of prostatitis, in order to prevent the transformation of hypertrophic to cancerous cells.

Toxins, 2013

Ochratoxin A (OTA) is a mycotoxin involved in the development of different types of cancers in ra... more Ochratoxin A (OTA) is a mycotoxin involved in the development of different types of cancers in rats, mice and humans. A growing number of in vitro and in vivo studies has been collected and has described evidence compatible with a role for oxidative stress in OTA toxicity and carcinogenicity. Because the contribution of the oxidative stress response in the development of cancers is well established, a role in OTA carcinogenicity is plausible. Several studies have been performed to try to counteract the adverse effects of oxygen radicals generated under OTA-exposure. A number of molecules with various antioxidant properties were tested, using in vivo or in vitro models. Protection against OTA-induced DNA damage, lipid peroxidation, as well as cytotoxicity were observed, further confirming the link between OTA toxicity and oxidative damage. These studies demonstrated that antioxidants are able to counteract the deleterious effects of chronic consumption or exposure to OTA and confirmed the potential effectiveness of dietary strategies to counteract OTA toxicity.

Transplantation Proceedings, 2007

Nitric oxide (NO), produced by nitric oxide synthase, is implicated in the pathophysiology of ren... more Nitric oxide (NO), produced by nitric oxide synthase, is implicated in the pathophysiology of renal ischemia/reperfusion (I/R) injury. This study sought to elucidate the impact of pharmacological induction of heme oxygenase-1 (HO-1) on renal I/R injury. Rats were subjected to 45 minutes of renal ischemia followed by various times of reperfusion (30 minutes, 1 hour, or 3 hours). Plasma from sacrificed rats was obtained, and the kidneys processed for the expression of iNOS, cleaved caspase-3, p38MAPK and for immunohistochemical analysis. Furthermore, we determined renal and plasma levels of lipid hydroperoxides, total thiol groups, and plasmatic NO 2 Ϫ /NO 3 Ϫ formation. Our results showed a time-dependent increase in iNOS expression, which was also confirmed by increased plasma formation of NO 2 Ϫ /NO 3 Ϫ . Interestingly, this effect was reversed by pretreatment (12 hours) with SnCl 2 , a potent and specific inducer of renal HO-1 expression and activity, or by intraperitoneal injection of biliverdin (10 mg/kg). Furthermore, we observed a concomitant reduction in plasma and renal LOOH formation, a normalization of renal total thiol content, a reduction of caspase-3-mediated apoptosis, and a significant increase in p38MAPK phosphoration. Taken together, these results suggested that HO-1 and its byproduct biliverdin play major roles in the pathophysiological cascade leading to renal I/R injury.

Phytotherapy Research, 2011

Berberis aetnensis C. Presl. is a bushy-spiny shrub common on Mount Etna (Sicily, Italy), contain... more Berberis aetnensis C. Presl. is a bushy-spiny shrub common on Mount Etna (Sicily, Italy), containing various alkaloids with several pharmacological properties. This study assessed the effect of berberine and of the alkaloid extract of B. aetnensis roots on the glutamate-evoked tissue transglutaminase (TG2) up-regulation in rat astrocyte primary cultures, used as an in vitro model of excitotoxicity. The findings show that the alkaloid extract of B. aetnensis roots consists mainly of berberine. Furthermore, berberine and the alkaloid extract of B. aetnensis roots were able to restore the oxidative status modified by glutamate and the levels of TG2 to control values. It was found that berberine or the alkaloid extract of B. aetnensis roots are able to ameliorate the excessive production of glutamate, protein misfolding and aggregation, mitochondrial fragmentation, and neurodegeneration. Thus, it is suggested that berberine and the alkaloid extract of B. aetnensis roots, may represent a natural therapeutic strategy in the neuropathological conditions associated with excitotoxicity.

Nitric Oxide, 2006

The reperfusion of ischemic tissue often delays its physiological and functional recovery; this p... more The reperfusion of ischemic tissue often delays its physiological and functional recovery; this paradoxical effect is ascribed to increased release of free radicals including O 2 ÅÀ and NO. For these reasons, scavenging reactive oxygen species or inhibition the NO synthesis has been shown to result in an enhanced neuronal survival after cerebral ischemia. Many authors believe that therapy for stroke patients would be a cocktail of drugs with various mechanisms of action. Combination therapy is a difficult and complicated avenue for drug development because of the possibility of drug-drug interactions. An alternative approach would be to combine multiple activities within the same compound. In consideration of the free-radical scavenging and inhibitory effect on NOS of various natural and synthetic compounds, the aim of this study was to analyze the antioxidant properties of some imidazole derivatives previously synthesized in our laboratory. Results obtained in the present study provide evidence that tested compounds exhibit interesting antioxidant properties, expressed either by their capacity to scavenge free radicals or their ability to reduce lipid peroxidation. In particular, compounds A and B represent chemical structures which can be easily modified to improve the observed antioxidant properties and to provide new therapeutic strategies focused on multiple downstream events.

Neuroscience Letters, 2010

The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields ... more The exposure of primary rat neocortical astroglial cell cultures to acute electromagnetic fields (EMF) in the microwave range was studied. Differentiated astroglial cell cultures at 14 days in vitro were exposed for 5, 10, or 20min to either 900MHz continuous waves or 900MHz waves modulated in amplitude at 50Hz using a sinusoidal waveform and 100% modulation index. The strength of the electric field (rms value) at the sample position was 10V/m. No change in cellular viability evaluated by MTT test and lactate dehydrogenase release was observed. A significant increase in ROS levels and DNA fragmentation was found only after exposure of the astrocytes to modulated EMF for 20min. No evident effects were detected when shorter time intervals or continuous waves were used. The irradiation conditions allowed the exclusion of any possible thermal effect. Our data demonstrate, for the first time, that even acute exposure to low intensity EMF induces ROS production and DNA fragmentation in astrocytes in primary cultures, which also represent the principal target of modulated EMF. Our findings also suggest the hypothesis that the effects could be due to hyperstimulation of the glutamate receptors, which play a crucial role in acute and chronic brain damage. Furthermore, the results show the importance of the amplitude modulation in the interaction between EMF and neocortical astrocytes.

Molecules, 2013

Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils,... more Momordica foetida Schumach. et Thonn. (Cucurbitaceae) is a perennial climbing herb with tendrils, found in swampy areas in Central Uganda. Antidiabetic and antilipogenic activities were reported for some Momordica species, however the mechanism of action is still unknown. Oxidative stress may represent an important pathogenic mechanism in obesity-associated metabolic syndrome. The present study evaluated free radical scavenging capacity of different concentrations of aqueous, methanolic and dichloromethane leaf extracts of Momordica foetida Schumach. et Thonn. and the ability of these extracts to inhibit in vitro plasma lipid peroxidation; in addition, healthy human adipose mesenchymal stem cell cultures were used in order to test the hypothesis that these extracts may affect adipocyte differentiation. Results obtained in this study suggested that aqueous extract might be useful in preventing metabolic syndrome.

Microsurgery, 2006

Ischemia/reperfusion (I/R) injury is a multifactorial process that affects liver function after t... more Ischemia/reperfusion (I/R) injury is a multifactorial process that affects liver function after transplantation and resectional surgery. Alterations in hepatic microcirculation and decreased hepatic flow can cause local hypoxia and consequently liver damage, which is worsened by reperfusion. The aim of this study was to evaluate if treatment with L-arginine improved hepatic function in rats with I/R injury. Animals were treated with L-arginine, ischemized for 30 min, and reperfused for 3 h. Plasmatic levels of GOT, GPT, lipid hydroperoxides (LOOH), and total thiol groups (RSH) were evaluated. In addition, we analyzed hepatic LOOH and RSH levels, DNA fragmentation, heme oxygenase 1 (HO-1) expression, and histological modifications. Our results demonstrate a significant improvement in hepatic function of I/R rats compared to the control group. Treatment with L-arginine increased the expression of HO-1. These data suggest that L-arginine could be useful in preventing oxidative damage during hepatic surgery. ª 2006 Wiley-Liss, Inc. Microsurgery 26: 25À32, 2006.