Tahia Boudawara

Hypolipidemic and hepatoprotective effects of flax and pumpkin seed mixture rich in ω-3 and ω-6 fatty acids in hypercholesterolemic rats

Flax and pumpkin seeds are a rich source of unsaturated fatty acids, antioxidants and fibers, known to have anti-atherogenic and hepatoprotective activities. These effects were evaluated in Wistar rats fed with 1% cholesterol diet. The study was performed on 30 male rats divided into three groups: a control group (CD), CD-chol group fed diet with 1% cholesterol and MS-chol group fed diet enriched with flax and pumpkin seed mixture. In CD-chol group, total cholesterol TC, triacylglycerol TG in plasma and liver, plasma LDL-C, atherogenic index AI and LDL/HDL ratio significantly increased. In MS-chol group lipid parameters decreased significantly, plasma and liver fatty acid composition showed an increase of PUFAs (ALA and LA), and MUFAs (oleic and eicosaenoic acid) and a decrease of SFA (palmitic and stearic acid). In plasma and liver of MS-chol group, malondialdehyde levels decreased and the efficiency of antioxidant defense system was improved compared to CD-chol group. Liver histological sections showed lipid storage in hepatocytes of CD-chol group and an improvement was noted in MS-chol group. Our results suggested that flax and pumpkin seed mixture had anti-atherogenic and hepatoprotective effects which were probably mediated by unsaturated fatty acids present in seed mixture.

Evaluation of the antioxidant, anti-inflammatory and hepatoprotective properties of vanillin in carbon tetrachloride-treated rats.

The antioxidant and anti-inflammatory effects of vanillin are considered as important forces in the protection against liver injury and fibrosis. This study investigated the protective effects of vanillin against carbon tetrachoride (CCl(4))-induced hepatotoxicity in rat. Pretreatment with vanillin prior the administration of CCl(4) significantly prevented the decrease of protein synthesis and the increase in plasma alanine (ALT) and aspartate (AST) aminotransferases. Furthermore, it inhibited hepatic lipid peroxidation (MDA) and protein carbonyl (PCO) formation and attenuated the (CCl(4))-mediated depletion of antioxidant enzyme catalase and superoxide dismutase (SOD) activities and glutathione level (GSH) in the liver. In addition, vanillin markedly attenuated the expression levels of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) and prevented CCl(4)-induced hepatic cell alteration and necrosis, as indicated by liver histopathology. These findings suggest that the antioxidant and anti-inflammatory effects of vanillin against CCl(4)-induced acute liver injury may involve its ability to block CCl(4)-generated free radicals.

Protective effects of Selenium (Se) on Chromium (VI) induced nephrotoxicity in adult rats.

Chromium is a toxic metal implicated in human diseases. This study was focused on investigating the possible protective effect of Se against K(2)Cr(2)O(7). Female Wistar rats, used in this study, were divided into four groups of six animals each: group I served as control which received standard diet; group II received orally only K(2)Cr(2)O(7) (700 ppm equivalent to 67 mg/kgbw); group III received both K(2)Cr(2)O(7) and Se (0.5 mg/kg of diet); group IV received Se (0.5mg Na(2)SeO(3)/kg of diet). The exposure of rats to K(2)Cr(2)O(7) for 21 days provoked renal damages with a significant increase in kidney malondialdehyde, superoxide dismutase, plasma creatinine, and uric acid levels, while catalase, glutathione peroxidase, non-protein thiol, Metallothionein and plasma urea levels decreased. Coadministration of Se in the diet of chromium-treated group improved malondialdehyde, renal biomarkers levels and antioxidant enzyme activities. Kidney histological studies confirmed biochemical parameters and the beneficial role of selenium.

Flax and Pumpkin seeds mixture ameliorates diabetic nephropathy in rats

This study investigated the hypoglycemic and antioxidant effects of Flax and Pumpkin seeds mixture on the kidney of alloxan-induced diabetic rats. Animals were allocated into three groups of six rats each: a control group (CD), a diabetic group (DD) and diabetic rats fed with Flax and Pumpkin seeds mixture (DMS) group. The DD rats showed a significant increase of glycemia and lipid parameters such as total lipid, total cholesterol and triglycerides levels compared to those of the control group (CD). In addition, plasma and kidney malonaldialdehyde levels (MDA) were significantly increased compared to (CD) group. Antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD) and non-enzymatic levels of reduced glutathione (GSH) significantly decreased in the plasma and kidney of diabetic rats compared to those of controls. Diet supplemented with Flax and Pumpkin seeds mixture ameliorated the antioxidant enzymes activities observed in diabetic rats and significantly decreased MDA levels. Kidney histological sections, showed glomerular hypertrophy and tubular dilatation. In DMS rats, these histopathological changes were less prominent. Our results suggest that Flax and Pumpkin seeds mixture supplemented in diet of diabetic rats may be helpful to prevent diabetes and its complications.

Antioxidant effect of vitamin E and selenium on hepatotoxicity induced by dimethoate in female adult rats

Acute exposure to pesticides can cause hepatotoxicity. Our study pertains to the potential ability of selenium and/or vitamin E, used as nutritional supplements, to alleviate oxidative stress induced by dimethoate. Female Wistar rats were randomly divided into seven groups of six each: group I served as controls; group II received in their drinking water dimethoate (2 g L(-1)); group III received both dimethoate and selenium (0.5 mg/kg of diet); group IV was treated with dimethoate and vitamin E (100 mg/kg of diet); group V received dimethoate+selenium+vitamin E and groups VI and VII received either selenium or vitamin E. The exposure of rats to dimethoate for 30 days promoted oxidative stress with an increase in malondialdehyde and a decrease in glutathione and non-protein thiol levels. A decrease in glutathione peroxidase, superoxide dismutase and catalase activities was also observed. While, plasma transaminases, lactate dehydrogenase activities and bilirubin levels increased. Co-administration of selenium and/or vitamin E through diet improved the biochemical parameters cited above. Liver histological studies confirmed biochemical parameters and the beneficial roles of selenium and vitamin E.

Characterization of bioactive compounds and ameliorative effects of Ceratonia siliqua leaf extract against CCl4 induced hepatic oxidative damage and renal failure in rats

Ceratonia siliqua is a typical Mediterranean plant, mainly used in food and Tunisian traditional folk medicine. Among the tested extracts, the ethyl acetate fraction (EACs) exhibited the highest total phenolic and flavonoids content. The antioxidant activity in vitro systems showed a more significant potent free radical scavenging activity of this extract than other analysis fractions. The HPLC finger print of EACs active extract showed the presence of six phenolic compounds. The in vivo results showed that oral administration of CCl(4) enhanced levels of hepatic and renal markers (ALT, AST, ALP, LDH, γ-GT, urea and creatinine) in the serum of experimental animals. It also increased the oxidative stress markers resulting in increased levels of the lipid peroxidation with a concomitant decrease in the levels of enzymatic antioxidants (SOD, CAT, GPx) in both liver and kidney. The pre-treatment of experimental rats with 250 mg/kg (BW) of the EACs, by intraperitoneal injection for 8 days, prevented CCl(4) induced disorders in the levels of hepatic and kidney markers. The biochemical changes were in accordance with histopathological observations suggesting a marked hepatoprotective and nephroprotective effect of the EACs extract.

Effects of selenium on chromium (VI)-induced hepatotoxicity in adult rats

Chromium, a major environmental pollutant, is known for its wide toxic manifestations. The present experiment pertains to the protective role of selenium (Se) against K(2)Cr(2)O(7)-induced hepatotoxicity. Female Wistar rats were divided into four groups of six each: group I served as controls which received standard diet; group II received in drinking water K(2)Cr(2)O(7) alone (700 ppm); group III received both K(2)Cr(2)O(7) and Se (0.5 Na(2)SeO(3) mg/kg of diet); group IV received Se (0.5 mg/kg of diet) for 3 weeks. Exposure of rats to chromium promoted oxidative stress with an increase in malondialdehyde (MDA) and a decrease in glutathione (GSH) levels. A decrease in glutathione peroxidase (GPx) and an increase in superoxide dismutase (SOD) and catalase (CAT) activities were observed. Se supplementation to the diet of group III improved all the parameters cited above. Yet, plasma transaminases (AST and ALT), lactate dehydrogenase (LDH) activities, cholesterol, triglycerides (TG) and low density lipoprotein-cholesterol (LDL-C) levels increased, while high density lipoprotein-cholesterol (HDL-C) decreased. Co-administration of Se to the diet of group III restored hepatic markers to near-normal values. The biochemical results confirmed the histopathological findings. Therefore, our investigation revealed that Se was effective in preventing K(2)Cr(2)O(7)-induced hepatotoxicity.

Cardioprotective effects of selenium on chromium (VI)-induced toxicity in female rats.

Acute exposure to hexavalent chromium compounds can cause cardiotoxicity. Our study pertains to the protective effect of selenium against K(2)Cr(2)O(7)-induced cardiotoxicity. Female Wistar rats were divided into four groups of six each: group I served as controls which received standard diet; group II received in drinking water K(2)Cr(2)O(7) alone (700 ppm); group III received both K(2)Cr(2)O(7) and Se (0.5 Na(2)SeO(3) mg/kg of diet); group IV received Se (0.5 mg/kg of diet) for 3 weeks. The exposure of rats to chromium promoted oxidative stress with an increase in malondialdehyde levels and a decrease in antioxidant non-enzymatic levels such as glutathione, non-protein thiol and vitamin C, while, an increase in glutathione peroxidase, superoxide dismutase and catalase activities was observed. However, plasma transaminases, lactate dehydrogenase activities, cholesterol, triglycerides and low density lipoprotein-cholesterol levels increased, and high density lipoprotein-cholesterol decreased. Coadministration of Se restored the parameters cited above to near-normal values. The histopathological findings confirmed the biochemical results.

Hypolipidemic and hepatoprotective seeds mixture diet rich in ω-3 and ω-6 fatty acids

In vitro physicochemical and antioxidant properties of mixture of Flax/Sesame (LS) and Flax/Peanut (LA) and in vivo hypolipidemic, antioxidant and hepatoprotective activities were carried out to ascertain the claim of its utilisation against diseases. The seeds mixture rich in unsaturated fatty acids were prepared with 5/1 ratio of omega-6/omega-3 fatty acids and were orally administered ad libitum to rats by standard diet for 30 days. High cholesterol fed diet rats (CD-chol) exhibited a significant increase in total plasma and liver lipid parameters and atherogenicity and a significant decrease in high-density lipoproteins (HDL) and HDL/TC ratio (HTR). Administration of (LS) or (LA) seeds mixture to hypercholesterolemic rats (MS-LSchol and MS-LAchol groups respectively) significantly ameliorated lipid parameters and showed an increase of PUFAs (ALA and LA) and MUFAs and a decrease of SFAs in plasma and liver of MS-LSchol and MS-LAchol groups. Furthermore, malondialdehyde levels decreased and the efficiency of antioxidant defense system was improved compared to CD-chol group. Liver histological sections showed lipid storage in hepatocytes of CD-chol group and an improvement was noted in both supplemented groups. Our results suggested that seeds mixtures of Flax/Sesame and Flax/Peanut have anti-atherogenic and hepatoprotective effects.

Protective role of silymarin against manganese-induced nephrotoxicity and oxidative stress in rat.

Metal toxicity may occur after exposure from many sources. Oxidative stress is thought to be involved in manganese‐induced toxicity and leads to various health disorders. Silymarin (SIL), a natural flavonoid, has been reported to have many benefits and medicinal properties. The aim of this study was to assess the toxicity of manganese (Mn) on oxidative stress and DNA damage in the kidney of rats and its alleviation by SIL. Manganese was given orally in drinking water (20 mg MnCl2/mL) with or without SIL administration (100 mg /kg intraperitoneally) for 30 days. Our data showed that SIL significantly prevented Mn induced nephrotoxicity, indicated by both diagnostic indicators of kidney injury like plasma urea, uric acid and creatinine and urinary electrolyte levels and by histopathological analysis. Moreover, Mn‐induced profound elevation of the production of reactive oxygen species (ROS) and altered the levels of oxidative stress related biomarkers in kidney tissue. This is evidenced by the increase of lipid peroxidation, protein carbonylation, DNA fragmentation and urinary hydrogen peroxide, while, the activities of enzymatic antioxidant and glutathione level were decreased. Treatment with SIL reduced the alterations in the renal and urine markers, decreasing lipid peroxidation markers, increasing the antioxidant cascade and decreasing the Mn‐induced damage. All these changes were supported by histopathological observations. These findings suggested that the inhibition of Mn‐induced damage by SIL was due at least in part to its antioxidant activity and its capacity to modulate the oxidative damage.