Metformin protects against diabetes-induced heart injury and dunning prostate cancer model.

In this study, both diabetes and Dunning prostate cancer were induced for the first time in Copenhagen rats in vivo. Thus, the effects of metformin against heart tissue damage of these rats were investigated by biochemical methods. Dunning prostate cancer was induced in Copenhagen rats using high metastatic MAT-LyLu cells. The rats were divided as follows: Control group: only injected with 0.9% NaCl for 14 days; Diabetic group: only injected single dose of streptozotocin (STZ) (65 mg/kg); Cancer group: subcutaneously (s.c) inoculated with 2 x 104 MAT-LyLu cells only; Diabetic + cancer (DC) group: inoculated with 2 x 104 MAT-LyLu cells and STZ injection, Cancer + metformin (CM) group: injected with metformin for 14 days after Mat-LyLu cells application; Diabetic + cancer + metformin (DCM) group: metformin administered for 14 days together with STZ and Mat-LyLu cells. At the end of the experimental period, heart tissues were taken. Reduced glutathione and total antioxidant status levels in heart tissues were decreased, whereas lipid peroxidation, advanced oxidized protein products, nitric oxide, homocysteine, and reactive oxygen species levels, total oxidant status and catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and xanthine oxidase activities increased in the diabetic, cancer and DC groups. Treatment with metformin reversed these effects. In conclusion, the present study shows that metformin has a protective effect against heart tissue damage in STZ-induced diabetic rats with Dunning prostate cancer.

Galectin-1 exhibits a protective effect against hepatotoxicity induced by dextran sulfate sodium in mice.

Galectin-1 is an important mediator that regulates the T-cell-mediated immune response. It has many other biological functions such as cell growth, immunomodulation, and wound healing. The aim of this study was to reveal the role of galectin-1 on liver morphology, cell proliferation, apoptosis, inflammatory and anti-inflammatory mediators, oxidative stress, and antioxidant system in colitis-mediated hepatotoxicity induced by dextran sulfate sodium (DSS). In the present study, adult mice were divided into four groups: The control group intraperitoneally injected with phosphate buffer saline (I), the group which was orally administered with DSS (II), the control group which was injected with galectin-1 (III), and the group which was given DSS and galectin-1 (IV). DSS administration caused degenerative changes and diffuse necrotic damage, an increase in caspase-3 and cyclooxygenase-2 expression, the levels of lipid peroxidation and tumor necrosis factor-alpha, lactate dehydrogenase, and myeloperoxidase activities, and a decrease in cell proliferation, interleukin-10 levels, and antioxidant system parameters in liver tissues. Treatment of DSS group with galectin-1 reversed these effects and prevented liver damage. This study showed that galectin-1 has proliferative, antiapoptotic, anti-inflammatory, and antioxidant effects against DSS-induced liver injury in mice. It is expected considering all results of this study that galectin-1 may be useful as a protective agent against liver toxicity.

Edaravone ameliorates the adverse effects of valproic acid toxicity in small intestine.

Valproic acid (VPA) is a drug used for the treatment of epilepsy, bipolar psychiatric disorders, and migraine. Previous studies have reported an increased generation of reactive oxygen species and oxidative stress in the toxic mechanism of VPA. Edaravone, a free radical scavenger for clinical use, can quench free radical reaction by trapping a variety of free radical species. In this study, effect of edaravone on some small intestine biochemical parameters in VPA-induced toxicity was investigated. Thirty seven Sprague Dawley female rats were randomly divided into four groups. The groups include control group, edaravone (30 mg(-1) kg(-1) day(-1)) given group, VPA (0.5 g(-1) kg(-1) day(-1)) given group, VPA + edaravone (in same dose) given group. Edaravone and VPA were given intraperitoneally for 7 days. Biochemical parameters such as malondialdehyde, as an index of lipid peroxidation(LPO), sialic acid (SA), glutathione levels and glutathione peroxidase, glutathione-S-transferase, superoxide dismutase, catalase, myeloperoxidase, alkaline phosphatase (ALP), and tissue factor (TF) activities were determined in small intestine samples by colorimetric methods. Decreased small intestine antioxidant enzyme activities, increased LPO and SA levels, and increased activities of ALP and TF were detected in the VPA group. Based on our results edaravone may be suggested to reverse the oxidative stress and inflammation due to VPA-induced small intestine toxicity.

Vitamin U, a novel free radical scavenger, prevents lens injury in rats administered with valproic acid.

Valproic acid (2-propyl-pentanoic acid, VPA) is the most widely prescribed antiepileptic drug due to its ability to treat a broad spectrum of seizure types. VPA exhibits various side effects such as organ toxicity, teratogenicity, and visual disturbances. S-Methylmethioninesulfonium is a derivative of the amino acid methionine and it is widely referred to as vitamin U (Vit U). This study was aimed to investigate the effects of Vit U on lens damage parameters of rats exposed to VPA. Female Sprague Dawley rats were divided into four groups. Group I comprised control animals. Group II included control rats supplemented with Vit U (50 mg/kg/day) for 15 days. Group III was given only VPA (500 mg/kg/day) for 15 days. Group IV was given VPA + Vit U (in same dose and time). Vit U was given to rats by gavage and VPA was given intraperitoneally. On the 16th day of experiment, all the animals which were fasted overnight were killed. Lens was taken from animals, homogenized in 0.9% saline to make up to 10% (w/v) homogenate. The homogenates were used for protein, glutathione, lipid peroxidation levels, and antioxidant enzymes activities. Lens lipid peroxidation levels and aldose reductase and sorbitol dehydrogenase activities were increased in VPA group. On the other hand, glutathione levels, superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase, and paraoxonase activities were decreased in VPA groups. Treatment with Vit U reversed these effects. This study showed that Vit U exerted antioxidant properties and may prevent lens damage caused by VPA.

Protective effect of vanadyl sulfate on skin injury in streptozotocin-induced diabetic rats.

The aim of the present study was to investigate the effect of vanadyl sulfate supplementation on the skin tissues of diabetic and control rats. In this study, 6-6.5 months old male Swiss albino rats were used. The animals were randomly divided into the following four groups: group I, control (nondiabetic intact animals); group II, vanadyl sulfate control; group III, streptozotocin (STZ)-diabetic animals and group IV, STZ-diabetic animals given vanadyl sulfate. The animals were made diabetic by intraperitoneal injection of a single dose of 65 mg/kg STZ in 0.01 M citrate buffer (pH = 4.5). From day 1 to day 60, 100 mg/kg vanadyl sulfate was given daily by gavage technique to one of the control and diabetic groups. Body weights and blood glucose levels were estimated on experimental days 0, 1 and 60. On the 60th day, skin tissue samples were taken, glutathione (GSH), lipid peroxidation (LPO), nonenzymatic glycosylation (NEG) and protein levels, catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were determined. Blood glucose, skin LPO and NEG levels increased, but skin GSH levels and CAT, SOD and GST activities decreased in the STZ group. Treatment with vanadyl sulfate reversed these effects. The present study showed that vanadyl sulfate exerted antioxidant properties and may prevent skin damage caused by diabetes.

Protective effect of vanadyl sulfate on skin injury in streptozotocin-induced diabetic rats.

The aim of the present study was to investigate the effect of vanadyl sulfate supplementation on the skin tissues of diabetic and control rats. In this study, 6-6.5 months old male Swiss albino rats were used. The animals were randomly divided into the following four groups: group I, control (nondiabetic intact animals); group II, vanadyl sulfate control; group III, streptozotocin (STZ)-diabetic animals and group IV, STZ-diabetic animals given vanadyl sulfate. The animals were made diabetic by intraperitoneal injection of a single dose of 65 mg/kg STZ in 0.01 M citrate buffer (pH = 4.5). From day 1 to day 60, 100 mg/kg vanadyl sulfate was given daily by gavage technique to one of the control and diabetic groups. Body weights and blood glucose levels were estimated on experimental days 0, 1 and 60. On the 60th day, skin tissue samples were taken, glutathione (GSH), lipid peroxidation (LPO), nonenzymatic glycosylation (NEG) and protein levels, catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) activities were determined. Blood glucose, skin LPO and NEG levels increased, but skin GSH levels and CAT, SOD and GST activities decreased in the STZ group. Treatment with vanadyl sulfate reversed these effects. The present study showed that vanadyl sulfate exerted antioxidant properties and may prevent skin damage caused by diabetes.

Combined effects of treatment with vitamin C, vitamin E and selenium on the skin of diabetic rats.

The aim of this study was to investigate the effects of vitamin C, vitamin E and selenium (Se) on the skin tissue of streptozotocin-induced diabetic rats. Swiss albino rats were divided into four groups: control, control + antioxidants, diabetic, diabetic + antioxidants groups. Diabetes was induced by intraperitoneal injection of 65 mg/kg streptozotocin. Vitamin C (250 mg/kg), vitamin E (250 mg/kg) and Se (0.2 mg/kg) were given by gavage technique to rats of one diabetic and one control group for 30 days. In the diabetic group, the levels of serum urea and creatinine, skin lipid peroxidation and nonenzymatic glycosylation levels increased, but skin glutathione levels decreased. Treatment with vitamin C, vitamin E and Se reversed these effects. The present study showed that vitamin C, vitamin E and Se exerted antioxidant effects and consequently may prevent skin damage caused by streptozotocin-induced diabetes.

The effect of zinc supplementation on ghrelin-immunoreactive cells and lipid parameters in gastrointestinal tissue of streptozotocin-induced female diabetic rats.

Zinc is an essential nutrient with a wide range of functions and closely involved in a variety of enzymatic processes of importance in glucose, protein and lipid metabolism. Ghrelin is the endogenous ligand of the G protein coupled growth hormone secretagogue receptor. The regulatory mechanism that explain the biosynthesis and secretion of ghrelin in the gastrointestinal tract has not been clarified. This study was undertaken to examine the effect of zinc supplementation on the streptozotocin (STZ)-induced diabetic rats, which exhibits ghrelin production and secretion, and lipid metabolism on the gastrointestinal tract. The animals were divided into four groups. Group I: Non-diabetic untreated animals. Group II: Zinc-treated non-diabetic rats. Group III: STZ-induced diabetic untreated animals. Group IV: Zinc-treated diabetic animals. Zinc sulfate was given to some of the experimental animals by gavage at a dose of 100 mg/kg body weight every day for 60 days. In the zinc-treated diabetic group, the blood glucose levels decreased and body weight increased as compared to the diabetic untreated group. Zinc supplementation to STZ-diabetic rats revealed the protective effect of zinc on lipids parameters such as total lipid, cholesterol, HDL-cholesterol and atherogenic index. There is no statistically change in ghrelin-immunoreactive cells in gastrointestinal tissue. But, it has found that zinc supplementation caused a significant reduction in densities of ghrelin-producing cells of fundic mucosa of zinc-treated diabetic animals as compared to untreated, non-diabetic controls. Zinc supplementation may contribute to prevent some complications of diabetic rats, biochemically.

Protective role of Melissa officinalis L. extract on liver of hyperlipidemic rats: a morphological and biochemical study.

In this study, the effects of Melissa officinalis L. extract on hyperlipidemic rats were investigated, morphologically and biochemically. The animals were fed a lipogenic diet consisting of 2% cholesterol, 20% sunflower oil and 0.5% cholic acid added to normal chow and were given 3% ethanol for 42 days. The plant extract was given by gavage technique to rats to a dose of 2 g/kg every day for 28, 14 days after experimental animals done hyperlipidemia. The degenerative changes were observed in hyperlipidemic rats, light and electron microscopically. There was a significant increase in the levels of serum cholesterol, total lipid, alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP), a significant decrease in the levels of liver tissue glutathione (GSH), a significant increase in the levels of tissue lipid peroxidation (LPO) in this group. On the other hand, the administration of Melissa officinalis L. extract reduced total cholesterol, total lipid, ALT, AST and ALP levels in serum, and LPO levels in liver tissue, moreover increased glutathione levels in the tissue. As a result, it was suggested that Melissa officinalis L. extract exerted an hypolipidemic effect and showed a protective effect on the liver of hyperlipidemic rats.

Protective effects of metformin treatment on the liver injury of streptozotocin-diabetic rats.

Metformin is a biguanide derivate used as an oral hypoglycaemic drug in diabetics. The aim of this study was to examine the histological and biochemical effects of metformin in streptozotocin (STZ)-treated rats. The animals were rendered diabetic by intraperitoneal injection of 65 mg/kg STZ. Fourteen days later, metformin was given at 25 mg/kg by gavage, daily for 28 days, to STZ-diabetic rats and a control group. In the STZ-diabetic group, some degenerative changes were observed by light microscopic examination. But the degenerative changes were decreased in the STZ-diabetic group given metformin. In the STZ-diabetic group, blood glucose levels, serum alanine and aspartate transaminase (ALT and AST) activities, total lipid levels, and sodium and potassium levels increased, while body weight, serum magnesium levels and liver glutathione (GSH) levels decreased. In the STZ-diabetic group given metformin, blood glucose levels, serum ALT and AST activities, total lipid, and sodium and potassium levels decreased, and liver GSH and serum magnesium levels increased. As a result of all the morphological and biochemical findings obtained, it was concluded that metformin has a protective effect against the hepatotoxicity produced by STZ diabetes.

The protective effect of vitamin C, vitamin E and selenium combination therapy on ethanol-induced duodenal mucosal injury.

In this study, the effect of a combination of vitamin C, vitamin E and selenium on ethanol-induced duodenal mucosal damage in rats was investigated morphologically and biochemically. The duodenal mucosal injury was produced by oral administration of 1 mL of absolute ethanol to each rat. Animals received vitamin C (250 mg/ kg), vitamin E (250 mg/kg) and selenium (0.5 mg/kg) for 3 days and absolute ethanol 1 hour after last antioxidant administration and were sacrificed 1 hour after absolute ethanol. Extreme degeneration in intestinal mucosa of rats given ethanol was observed morphologically. In addition, an increase in neuronal nitric oxide synthase immunoreactive areas was observed in the rats of the group given ethanol. On the other hand, a normal morphological appearance and a decrease in neuronal nitric oxide synthase immunoreactive areas were detected in the rats given ethanol+vitamin C+vitamin E+ selenium. In the group to which ethanol was administered, an increase in serum cholesterol and a decrease in serum albumin levels were determined. On the other hand, in the group to which ethanol+vitamin C+vitamin E+selenium were administered, serum cholesterol value decreased, and the serum albumin level increased. As a result, we can say that the combination of vitamin C, vitamin E and selenium has a protective effect on ethanol-induced duodenal mucosal injury.

The morphological and biochemical effects of glibornuride on rat liver in experimental diabetes.

Glibornuride is a sulphonylurea derivative used as an oral hypoglycaemic drug in diabetics. The aim of this study was to examine the histological, ultrastructural and biochemical effects of glibornuride in streptozotocin (STZ)-treated rats. The animals were rendered diabetic by intraperitoneal injection of 65 mg/kg STZ. Fourteen days later, glibornuride was given at 5 mg/kg by gavage, daily for 28 days, to one STZ-diabetic and one control group. In the STZ-diabetic group, remarkable degenerative changes were observed. On the other hand, in the STZ-diabetic group given glibornuride, the degenerative changes decreased. In the STZ-diabetic group, blood glucose levels, serum aspartate transaminase activity, and total lipid levels increased, whereas the blood glutathione levels decreased. In contrast, in the STZ-diabetic group given glibornuride blood glucose levels, serum aspartate transaminase activity and total lipid levels decreased and blood glutathione levels increased. Significant changes in total protein levels in the serum were not observed in any group. As a conclusion, we can say that glibornuride has a protective effect against the hepatotoxicity produced by STZ-diabetes.

Effects of parsley (Petroselinum crispum) on the liver of diabetic rats: a morphological and biochemical study.

Parsley is used by diabetics in Turkey to reduce blood glucose. The present study aims to investigate both the morphological and biochemical effects of parsley on liver tissue. Rat hepatocytes were examined by light and electron microscopy. Degenerative changes were observed in the hepatocytes of diabetic rats. These degenerative changes were significantly reduced or absent in the hepatocytes of diabetic rats treated with parsley. Blood glucose levels, alanine transaminase and alkaline phosphatase were observed to be raised in diabetic rats. Diabetic rats treated with parsley demonstrated significantly lower levels of blood glucose, alanine transaminase and alkaline phosphatase. The present study suggests that parsley demonstrates a significant hepatoprotective effect in diabetic rats.

The effects of chard (Beta vulgaris L. var. cicla) extract on the kidney tissue, serum urea and creatinine levels of diabetic rats.

The aim of this work was to investigate the effects of chard (Beta vulgaris L. var. cicla) extract on serum urea and creatinine concentrations and on kidney tissue in normal and streptozotocin-diabetic rats. The extract was administered to rats at a dose of 2 g/kg every day for 28 days, 14 days after animals were made diabetic. On day 42, kidney tissue and blood samples were examined. Significant degenerative changes in kidney tissue of diabetic rats were observed, but in the group given chard extract, the morphology of kidney tissue was found to be nearly the same as the controls. Serum urea and creatinine levels significantly increased in the diabetic groups, but the chard extracts significantly reduced serum urea and creatinine levels. It is concluded that the extract of this plant may reduce serum urea and creatinine levels and confer a protective effect on the kidney of diabetic rats.

Effects of chard (Beta vulgaris L. var. cicla) extract on oxidative injury in the aorta and heart of streptozotocin-diabetic rats.

In diabetes mellitus, increased free radical formation raises the incidence of atherosclerosis and cardiovascular diseases. Regardless of the type of diabetes, the objective of the therapy is to achieve normoglycemia and to prevent or delay the complications. Chard (Beta vulgaris L. var. cicla) is used as a hypoglycemic agent by diabetic patients in Turkey. The aim of this study was to investigate the effect of feeding chard on diabetes-induced free radical-mediated injury in rat aorta and heart tissues. Female Swiss albino rats were randomly divided into four groups: control, diabetic, chard, and diabetic + chard. Rats were subjected to intraperitoneal streptozotocin (STZ, 65 mg/kg) to induce diabetes. Chard extract (2 g/kg) was given for 28 days beginning on the 14th day of the study. Aorta and heart tissue lipid peroxidation and glutathione levels as well as blood glucose levels were determined. The results of the present study indicate that lipid peroxidation was increased and glutathione levels were decreased in both aorta and heart tissue of the diabetic rats. However, treatment with chard extract reversed the effects of diabetes on blood glucose and tissue lipid peroxidation and glutathione levels.

The effect of Glurenorm (gliquidone) on lenses and skin in experimental diabetes.

The aim of this study was to investigate the effect of administering Glurenorm (gliquidone, 10 mg/kg) on the lenses and skins of streptozotocin-induced diabetic rats. The drug was given to both diabetic and control rats daily, until the end of the experiment, at day 42. The drug was administered to one diabetic and one control group from day 0 and for the other diabetic and control groups from day 14. On day 42, cardiac blood samples, skin samples, and lenses were taken from each rat. Blood glucose (BG) was measured by the o-toluidine method. The total protein, nonenzymatic glycosylation of proteins (NEG), lipid peroxidation (LPO), and glutathione (GSH) levels in the lens and skin homogenates were determined by the Lowry, thiobarbituric acid, Ledwozwy, and Ellman methods, respectively. Laemmli SDS polyacrylamide gel electrophoresis was also carried out on the lens or skin homogenates. After 42 d, Glurenorm given to the diabetic rats produced (i) significant reductions in BG, NEG, and total protein in the lenses; (ii) significant increases in GSH levels in the lenses; (iii) and no significant results in the skin. The body weights of the drug group dropped relative to day 0, but not significantly. SDS polyacrylamide gel electrophoresis revealed no significant differences in any of the protein bands between any of the groups. In the lenses, the gains in turns of reduced NEG and increased GSH may have been offset by the reduction in protein.

Total selenium concentration in various waters of Turkey.

The total selenium levels of 335 water samples of Turkey were determined by a spectrofluorometric method. The samples were digested in nitric-perchloric acid mixture, potential interferences were masked with disodium EDTA-HONH2.HCl and selenium was complexed with freshly prepared 2,3-diaminonaphthalene solution and estimated spectrofluorometrically after extraction in cyclohexane. The selenium content of various waters (rain, tap, mineral, sea, lake, river, bottled drinking waters and collected drinking waters from 42 cities in Turkey) were determined. The selenium levels were compared with the literature data from different countries.

Protective effects of DL-alpha-tocopherol acetate and sodium selenate on the liver of rats exposed to gamma radiation.

The aim of this study is to investigate whether vitamin E (as DL-alpha-tocopherol acetate) and selenium (as sodium selenate) exert a protective effect against radiation damage. The liver tissue of rats irradiated with a single dose of 1,000 cGy 60Co-gamma-irradiation was examined for morphological changes after the intraperitoneal (ip) administration DL-alpha-tocopherol acetate and sodium selenate as compared to controls. Also, the amounts of blood glutathione and serum alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and total protein were determined by spectrophotometric methods. Degenerative changes were observed under light and electron microscopy in the liver tissue of the control (radiation only) group. In the group receiving radiation and ip doses of DL-alpha-tocopherol acetate and sodium selenate, the damage to the liver tissue was minimal or absent. In the radiation-only group, a reduction of the blood glutathione level and increases in serum values of AST, ALT, ALP, and LDH activity were observed, whereas in the irradiation-treated group, the reverse was found to occur. Based on these morphological and biochemical observations, it was concluded that the ip administration of DL-alpha-tocopherol acetate and sodium selenate exerts a protective effect against liver radiation damage.

Effects of chard (Beta vulgaris L. var. Cicla) extract on pancreatic B cells in streptozotocin-diabetic rats: a morphological and biochemical study.

Chard (Beta vulgaris L. var. cicla) is used as a hypoglycemic agent by diabetic patients in Turkey. The present study was carried out in order to detect whether this plant, used in folk remedies for decreasing blood glucose levels, affects pancreatic B cells and blood glucose. In the diabetic group, a decrease in the number of B cells of Langerhans islets and in the secretory materials, a swollen granular endoplasmic reticulum cisternae and widened intercellular areas in some of B cells were observed. But, in a diabetic group given chard extract, an increase in the number of B cells of Langerhans islets and in the secretory granules were noted, together with many hypertrophic Golgi apparatus and granules of low densities. The extract while having no effect on blood glucose and body weight in the normal group, reduced the blood glucose value in streptozotocin-induced hyperglycemic animals. But, in a diabetic group given chard, the body weight significantly increased in comparison to the diabetic group; maximum reduction in blood glucose levels was observed on the 42nd day. According to the morphological and biochemical results obtained, it is concluded that the extract of this plant when administered by gavage may reduce blood glucose levels by regeneration of the B cells.