Gordana Gregorović

Effect of Croatian propolis on diabetic nephropathy and liver toxicity in mice

BackgroundIn the present study, we examined the antioxidant effect of water soluble derivative of propolis (WSDP) and ethanolic (EEP) extract of propolis on renal and liver function in alloxan-induced diabetic mice. In addition, we examined whether different extract of propolis could prevent diabetic nephropathy and liver toxicity by inhibiting lipid peroxidation in vivo.MethodsDiabetes was induced in Swiss albino mice with a single intravenous injection of alloxan (75 mg kg-1). Two days after alloxan injection, propolis preparations (50 mg kg-1 per day) were given intraperitoneally for 7 days in diabetic mice. Survival analysis and body weights as well as hematological and biochemical parameters were measured. The renal and liver oxidative stress marker malonaldehyde levels and histopathological changes were monitored in the liver and kidney of treated and control mice.ResultsAdministration of propolis to diabetic mice resulted in a significant increase of body weight, haematological and immunological parameters of blood as well as 100% survival of diabetic mice. Alloxan-injected mice showed a marked increase in oxidative stress in liver and kidney homogenate, as determined by lipid peroxidation. Histopathological observation of the liver sections of alloxan-induced diabetic mice showed several lesions including cellular vacuolization, cytoplasmic eosinophilia and lymphocyte infiltrations, but with individual variability.Treatment of diabetic mice with propolis extracts results in decreased number of vacuolized cells and degree of vacuolization; propolis treatment improve the impairment of fatty acid metabolism in diabetes. Renal histology showed corpuscular, tubular and interstitial changes in alloxan-induced diabetic mice. Test components did not improve renal histopathology in diabetic mice.ConclusionsPropolis preparations are able to attenuate diabetic hepatorenal damage, probably through its anti-oxidative action and its detoxification proccess as well as the potential to minimize the deleterious effects of free radicals on tissue. The protective role of propolis against the ROS induced damages in diabetic mice gives a hope that they may have similar protective action in humans.

Quercetin vs chrysin: effect on liver histopathology in diabetic mice.

Effects of flavonoids quercetin and chrysin on lipid peroxidation and histopathological changes in liver of diabetic mice were studied and compared with the antioxidant and reducing ability of quercetin and chrysin and their ability to chelate Fe2+ ions in vitro. Diabetes was induced in Swiss albino mice with a single intravenous injection of alloxan (75 mg kg−1). Two days after alloxan injection, flavonoid preparations (50 mg kg−1 per day) were given intraperitoneally for 7 days in diabetic mice. The lipid peroxidation was evaluated by measuring the malondialdehyde production using the 2-thiobarbituric acid test. Administration of quercetin and chrysin to diabetic mice resulted in a significant decrease in lipid peroxidation level in liver tissue. Treatment of diabetic mice with flavonoids solutions results in decreased number of vacuolated cells and degree of vacuolization of the liver tissue. The protective role of flavonoids against the reactive oxygen species–induced damages in diabetic mice gives a hope that they may exert similar protective action in humans.

Early toxic effects of fumonisin B1 in rat liver.

Mycotoxin fumonisin B1 (FB1) is hepatotoxic and carcinogenic in experimental animals. It is known that long-term exposure of experimental animals to FB1 causes apoptosis and lipid peroxidation. In this study, male adult Wistar rats were treated with single FB1 doses (5, 50, and 500 μg/kg b.w.) and sacrificed 4, 24, and 48 hours after treatment. Parameters of oxidative stress, histopathological changes, and DNA damage were monitored in the liver of treated and control animals. Parameters of oxidative stress were not affected by such treatment. A significant increase in apoptotic cells appeared in animals when 5 μg/kg b.w. dose was given and sacrificed after 24 hours with further increase at higher doses. In contrast to the number of mitotic figures and karyomegaly seen mostly at lower FB1 doses, necrosis was the prominent feature at higher doses. Significant increase in liver cells DNA mobility was observed 48 hours following treatment with 50 and 500 μg/kg b.w. as compared to control (tail length 15.2 ± 0.3, 16.4 ± 0.5, and 13.5 ± 0.1 μm, respectively). Tail intensity appeared to be more sensitive parameter for detecting DNA damage even at 5 μg/kg b.w. after 48 hours (1.69 ± 0.27% DNA; control 0.59 ± 0.11% DNA). This study proved that FB1-induced DNA damage is time- and dose-dependent, and that it could be caused in Wistar rats by a single dose.

Assessment of surface water in the vicinity of fertilizer factory using fish and plants

The genotoxic and toxic potential of polluted surface water exposed to a fertilizer factory effluent was evaluated using assays with fish (Cyprinus carpio) and plant (Lemna minor) model organisms. Beside classical physicochemical parameters, the contents of fluorides, some heavy metals and polycyclic aromatic hydrocarbons were analyzed as well. Surface water caused inhibition of plant growth and decrease of photosynthetic pigment content. Regarding DNA damage and oxidative stress parameters, both fish and plants showed similar response to the surface water. In confirmation to biochemical markers, histopathological analysis of gill and liver tissues revealed a higher incidence of lesions in fish exposed to polluted surface water. Generally, results obtained by biological monitoring were mostly in agreement with chemical analysis of the surface water, although several discrepancies were observed which might be due to difference in sensitivity of model organisms or in experimental conditions (laboratory and field exposure). The results imply that conventional chemical analysis should be extended to genotoxicity/toxicity assays as measured biological effects and the potential health hazard cannot be predicted based on the physicochemical characteristics of water samples alone.

Maturation, fecundity and reproductive cycle of spiny dogfish, Squalus acanthias, in the Adriatic Sea

Abstract We provide the first detailed information on the reproductive traits of the endangered spiny dogfish (Squalus acanthias) in the Adriatic Sea, based upon 224 specimens (132 females and 92 males) collected onboard of commercial bottom trawls between 2005 and 2007. The morphometry of gonads, gonadosomatic index (GSI) and histological examination of gonads were used to analyse maturation and gonadal development of the species. The length at 50% maturity was attained at 504 mm for males and 725 mm for females. Ovarian fecundity ranged from 4 to 18 follicles (mean±SD: 10.8±4.5) and uterine fecundity ranged from 6 to 18 embryos (mean±SD: 10.1±3.9). Total length of embryos with absorbed yolk sacs ranged between 200 and 215 mm. The GSI and the high proportion of mature spermatocysts in the testes suggests that a majority of mating activity occurs in June, November and December, while the seasonal distribution of the largest ova and full-term embryos indicate that ovulation and parturition occur during the summer. In comparison with other study areas, spiny dogfish in the Adriatic Sea attained sexual maturity at smaller sizes and obtained higher fecundity values than fish from other regions.

Naringenin ameliorates pathological changes in liver and kidney of diabetic mice: a preliminary study.

Abstract The effect of naringenin, a flavonoid found in grapefruit, orange, and tomato, on lipid peroxidation and histopathological changes in the liver and kidneys of alloxan-induced diabetic mice were investigated. Two days after alloxan injection (75 mg kg−1, i.v.), naringenin ethanolic solution (0.5 % v/v) was given to mice intraperitoneally (50 mg kg−1 per day) for seven days. Naringenin’s impact on lipid peroxidation was measured by the 2-thiobarbituric acid test and histopathological changes were examined under a light microscope. Naringenin administration resulted in a significant decrease of lipid peroxidation level in liver and kidney tissue, as well as in a decreased number of vacuolated liver cells and degree of vacuolisation. Indications of tissue repair in kidney suggested that amelioration of diabetes-induced renal damage could be achieved over a longer period of time. Findings suggest that naringenin could be considered a dietary supplement in the prevention or treatment of diabetic complications and other diseases connected with oxidative stress, and gives a hope that it could show similar effects in the treatment of diabetes in humans.

Effect of Quercetin on Bone Mineral Status and Markers of Bone Turnover in Retinoic Acid-Induced Osteoporosis

Abstract Retinoic acid-induced osteoporosis (RBM) is one of the most common causes of secondary osteoporosis. This study tested the anti-osteoporetic effect of quercetin in RBM-induced bone loss model (RBM). After 14-day supplementation of 13cRA to induce RBM, rats were administered with quercetin (100 mg/kg) or alendronate (40 mg/kg). We analysed changes in body and uterine weight of animals, femoral geometric characteristics, calcium and phosphorus content, bone weight index, bone hystology, bone mineral density (BMD), markers of bone turnover, lipid peroxidation, glutathione levels and SOD, CAT activity of liver, kidney spleen, and ovary as well as biochemical and haematological variables. In comparison to the control RBM rats, the treatment with quercetin increased bone weight index, BMD, osteocalcin level, femoral geometric characteristics, calcium and phosphorus content in the 13cRA-induced bone loss model. Histological results showed its protective action through promotion of bone formation. According to the results, quercetin could be an effective substitution for alendronate in 13cRA-induced osteoporosis. Good therapeutic potential of quercetin on rat skeletal system is based partly on its antioxidant capacity and estrogenic activity.

Naringenin ameliorates pathological changes in liver and kidney of diabetic mice: a preliminary study / Naringenin reducira histopatoloske promjene u jetri i bubregu miseva s dijabetesom.

Abstract The effect of naringenin, a flavonoid found in grapefruit, orange, and tomato, on lipid peroxidation and histopathological changes in the liver and kidneys of alloxan-induced diabetic mice were investigated. Two days after alloxan injection (75 mg kg−1, i.v.), naringenin ethanolic solution (0.5 % v/v) was given to mice intraperitoneally (50 mg kg−1 per day) for seven days. Naringenin’s impact on lipid peroxidation was measured by the 2-thiobarbituric acid test and histopathological changes were examined under a light microscope. Naringenin administration resulted in a significant decrease of lipid peroxidation level in liver and kidney tissue, as well as in a decreased number of vacuolated liver cells and degree of vacuolisation. Indications of tissue repair in kidney suggested that amelioration of diabetes-induced renal damage could be achieved over a longer period of time. Findings suggest that naringenin could be considered a dietary supplement in the prevention or treatment of diabetic complications and other diseases connected with oxidative stress, and gives a hope that it could show similar effects in the treatment of diabetes in humans.

Naringenin reducira histopatološke promjene u jetri i bubregu miševa s dijabetesom

Abstract The effect of naringenin, a flavonoid found in grapefruit, orange, and tomato, on lipid peroxidation and histopathological changes in the liver and kidneys of alloxan-induced diabetic mice were investigated. Two days after alloxan injection (75 mg kg−1, i.v.), naringenin ethanolic solution (0.5 % v/v) was given to mice intraperitoneally (50 mg kg−1 per day) for seven days. Naringenin’s impact on lipid peroxidation was measured by the 2-thiobarbituric acid test and histopathological changes were examined under a light microscope. Naringenin administration resulted in a significant decrease of lipid peroxidation level in liver and kidney tissue, as well as in a decreased number of vacuolated liver cells and degree of vacuolisation. Indications of tissue repair in kidney suggested that amelioration of diabetes-induced renal damage could be achieved over a longer period of time. Findings suggest that naringenin could be considered a dietary supplement in the prevention or treatment of diabetic complications and other diseases connected with oxidative stress, and gives a hope that it could show similar effects in the treatment of diabetes in humans.