Molecular mechanisms underlying the effect of diacerein on trichloroacetic acid-induced hepatic pre-neoplastic lesions in rats.

CONCLUSION: IL-1ß mediates angiogenesis indirectly, as it has been shown to induce hypoxia-inducible factor-1α (HIF-1α) which upregulates VEGF.

Hydrogen sulfide renal protective effects: possible link between hydrogen sulfide and endogenous carbon monoxide in a rat model of renal injury.

Hydrogen sulfide (H2S), along with nitric oxide (NO) and carbon monoxide (CO), proved to have renoprotective effects in various renal diseases. Therefore, this study investigated the renoprotective effect of H2S, in a renal injury model, and its crosstalk with other gasotransmitters such as CO. Thirty-two adult rats were divided into four groups: control, gentamicin (GEN)-treated, GEN + sodium hydrosulfide (NaHS), and GEN + NaHS + zinc protoporphyrin (ZnPP) groups. GEN was used to induce renal injury, NaHS is a water-soluble H2S, and ZnPP is a selective heme oxygenase-1 (HO-1) inhibitor used to inhibit CO synthesis in vivo. NaHS improved kidney functions in the GEN group as evidenced by significantly lower levels of renal injury markers: serum urea, creatinine, uric acid, urinary albumin excretion, and urinary albumin/creatinine. Moreover, NaHS administration to the GEN-treated group significantly lowered renal levels of NO and tumor necrosis factor-α with an increase in total antioxidant, HO-1, and interleukin-10 levels. Furthermore, NaHS administration downregulated the GEN-induced overexpression of the renal inducible nitric oxide synthase (iNOS) and upregulated the suppression of endothelial nitric oxide synthase (eNOS) with improvement in the histological examination and periodic acid Schiff (PAS) staining. However, this improvement in kidney function produced by NaHS was reduced by combination with ZnPP but still improved as compared with the GEN-treated group. The renoprotective effects of H2S can be through its effects on renal tissue antioxidants, pro-inflammatory and anti-inflammatory cytokines, and expression of eNOS and iNOS which can be partially dependent on CO pathway via induction of HO-1 enzyme.

Antioxidant, anti-inflammatory, and anti-apoptotic effects of zinc supplementation in testes of rats with experimentally induced diabetes.

One of the major obstacles that males with diabetes may confront is subfertility or infertility. Thus, the present study investigated the effect of co-administration of metformin and zinc (Zn) on the testes of streptozotocin-induced diabetic rats. Male albino rats were randomly divided into 4 groups: control group; untreated diabetic group; diabetic + metformin group, in which diabetic rats were treated orally with metformin (250 mg/kg) once daily for 4 weeks; and diabetic + metformin + Zn group, in which diabetic rats were treated orally with metformin in combination with Zn (10 mg/kg) once daily for 4 weeks. Concomitant administration of metformin and Zn produced a significant decrease in serum levels of glucose and insulin and testicular levels of malondialdehyde and tumor necrosis factor α. Additionally, there was a significant increase in serum levels of Zn, testosterone, and follicle-stimulating hormone, as well as testicular total antioxidant capacity and anti-apoptotic protein Bcl-2, when compared with both the diabetic and metformin-treated diabetic groups. Moreover, co-administration of Zn and metformin significantly improved testicular histopathology, with a significant reduction in percent area of collagen fibers and nuclear factor kappa B (p65) immunoreactivity and a significant increase in seminiferous tubule diameter and connexin 43 immunoreactivity as compared with the diabetic and metformin-treated diabetic groups. In conclusion, the combination of Zn and metformin was an efficacious and safe alternative treatment, as it had superior antihyperglycemic efficacy and provided additional benefits over metformin alone in rats with type 2 diabetes.

Effect of Sofosbuvir Plus Daclatasvir in Hepatitis C Virus Genotype-4 Patients: Promising Effect on Liver Fibrosis.

BACKGROUND/PURPOSE: The effect of sofosbuvir and daclatasvir in treatment of genotype 4 Hepatitis C Virus (HCV) is not well documented. This study investigated the safety and efficacy of sofosbuvir plus daclatasvir with or without ribavirin in treatment of HCV genotype 4 patients. The impact of therapy on liver fibrosis as well as the role of IL18 polymorphism in therapeutic outcome was assessed. METHODS: One hundred HCV genotype 4 patients were categorized into 2 groups. The group 1 comprised treatment naïve patients, with total serum bilirubin ≤ 1.2 mg/10-1 L, serum albumin ≥ 3.5 g/10-1 L, INR ≤ 1.2, and platelet count ≥ 150 × 109/L. This group was treated with sofosbuvir plus daclatasvir for 12 weeks. The group 2 included Peg-IFN-α-or sofosbuvir treatment experienced, or patients with at least 2 of the following findings: total serum bilirubin > 1.2 mg/10-1 L, serum albumin < 3.5 g/10-1 L, INR > 1.2, and platelet count < 150 × 109 L-1. Group 2 was treated with sofosbuvir-daclatasvir + ribavirin for 12 weeks, with the exception of sofosbuvir treatment experienced patients, who were treated with sofosbuvir/daclatasvir + ribavirin for 24 weeks. RESULTS: Sustained Virological Response (SVR12) (undetectable viremia12 weeks post-treatment), was 93.3% in group 1 and 87.5% in group 2 (total = 91%). Such high efficacy was accompanied with tolerable adverse effects as well as with significant improvement in liver fibrosis. No significant association was observed between IL18 polymorphism (rs1946518) at position -607 and achievement of SVR12 in HCV patients after treatment. CONCLUSION: Sofosbuvir plus daclatasvir, with or without ribavirin achieved high efficacy and safety in HCV genotype 4 patients. Their effects were accompanied with attenuation of liver fibrosis. Further wider-scale studies are needed to evaluate the actual role of IL18 polymorphisms in treatment response with sofosbuvir/daclatasvir.

Different effects of selective ß1-adrenoceptor antagonists, nebivolol or atenolol in acetaminophen-induced hepatotoxicity of rats.

Acetaminophen (APAP) overdose is a common cause of acute liver failure, and beta-blockers are commonly used drugs in clinical practice. This study aimed to evaluate the effect of two different beta-blocker agents as nebivolol and atenolol against APAP-induced hepatotoxicity. Male Wistar rats were treated with APAP (2 g/kg/day, p.o.) to induce hepatotoxicity. Our results showed that nebivolol and atenolol reduced heart rate and blood pressure. Nebivolol (5 mg/kg/day, p.o.) for 14 days has a hepatoprotective effect shown by significant decrease in hepatic injury parameters (serum AST and ALT) with significant suppression of hepatic malondialdehyde (MDA) and nitric oxide (NO) which were elevated with APAP administration. Also, nebivolol increased reduced glutathione (GSH) which was reduced with APAP administration. Moreover, immunohistochemical examination revealed that nebivolol treatment markedly reduced inducible nitric oxide synthase (iNOS) expression, while expression of endothelial nitric oxide synthase (eNOS) was markedly enhanced, as compared to APAP group. The protective effects of nebivolol were also verified histopathologically. On the other hand, as compared to APAP group, oral administration of atenolol (50 mg/kg) increased hepatic injury parameters but did not change hepatic NO, MDA, and GSH. In conclusion, this study revealed that nebivolol not atenolol is protective against APAP-induced hepatotoxicity possibly, in part, through its antioxidant activity, inhibition of iNOS expression, and induction of eNOS expression.

Ginsenoside-Rb1 ameliorates lithium-induced nephrotoxicity and neurotoxicity: Differential regulation of COX-2/PGE2 pathway.

To investigate the effect of Ginsenoside-Rb1 (GRb1) on lithium (Li+)-induced toxicity, GRb1 was given to rats orally (100mg/kg) for 14days. In independent groups, lithium chloride (4meq/kg/day i.p.) was administered at day 4 of the experiment for 10days, with or without GRb1. Li+ caused significant deterioration of behavioral responses including righting reflex, spontaneous motor activity and catalepsy. Li+ also caused distortion in normal renal, cerebral and cerebellum architecture and significantly worsened all kidney functional parameters tested compared to control. In addition, Li caused oxidative stress in both kidney and brain, evident by significant increase in malondialdehyde and nitric oxide levels, with decrease in reduced glutathione and catalase activity. Administration of GRb1 prior to Li+ significantly improved behavioral responses, renal and brain histopathological picture, kidney function tests and oxidative stress markers compared to sole Li+-treated group. Concomitant administration of GRb1 decreased Li+ levels by about 50% in serum, urine and brain and by 35% in the kidney. Interestingly, Li+ had a differential effect on cyclooxygenase (COX)-2/prostaglandin E2 (PGE2) pathway, as it significantly increased COX-2 expression and PGE2 level in the kidney, while decreasing them in the brain compared to control. On the other hand, administering GRb1 with Li+ suppressed COX-2/PGE2 pathway in both kidney and brain compared to Li+ alone. In conclusion, GRb1 can alter Li+ pharmacokinetics resulting in extensively decreasing its serum and tissue concentrations. Furthermore, COX-2/PGE2 pathway has a mechanistic role in the nephro- and neuro-protective effects of GRb1 against Li+-induced toxicity.

Sildenafil Ameliorates Gentamicin-Induced Nephrotoxicity in Rats: Role of iNOS and eNOS.

Gentamicin, an aminoglycoside antibiotic, is used for the treatment of serious Gram-negative infections. However, its usefulness is limited by its nephrotoxicity. Sildenafil, a selective phosphodiesterase-5 inhibitor, was reported to prevent or decrease tissue injury. The aim of this study is to evaluate the potential protective effects of sildenafil on gentamicin-induced nephrotoxicity in rats. Male Wistar rats were injected with gentamicin (100 mg/kg/day, i.p.) for 6 days with and without sildenafil. Sildenafil administration resulted in nephroprotective effect in gentamicin-intoxicated rats as it significantly decreased serum creatinine and urea, urinary albumin, and renal malondialdehyde and nitrite/nitrate levels, with a concomitant increase in renal catalase and superoxide dismutase activities compared to gentamicin-treated rats. Moreover, immunohistochemical examination revealed that sildenafil treatment markedly reduced inducible nitric oxide synthase (iNOS) expression, while expression of endothelial nitric oxide synthase (eNOS) was markedly enhanced. The protective effects of sildenafil were verified histopathologically. In conclusion, sildenafil protects rats against gentamicin-induced nephrotoxicity possibly, in part, through its antioxidant activity, inhibition of iNOS expression, and induction of eNOS production.

Carvedilol ameliorates early diabetic nephropathy in streptozotocin-induced diabetic rats.

Diabetic nephropathy results in end-stage renal disease. On the other hand, carvedilol has been reported to have various pharmacological properties. The aim of this study therefore is to evaluate the possible protective effect of carvedilol on streptozotocin-induced early diabetic nephropathy and various mechanisms underlie this effect in rats. Single i.p. injection of streptozotocin (65 mg/kg) was administered to induce early diabetic nephropathy in Wistar rats. Oral administration of carvedilol at a dose level of 1 and 10 mg/kg daily for 4 weeks resulted in nephroprotective effect as evident by significant decrease in serum creatinine level, urinary albumin/creatinine ratio, and kidney index as well as renal levels of malondialdehyde, nitric oxide, tumor necrosis factor- α , and cyclooxygenase-2 with a concurrent increase in creatinine clearance and renal reduced glutathione level compared to diabetic untreated rats. The protective effect of carvedilol was confirmed by renal histopathological examination. The electron microscopic examination indicated that carvedilol could effectively ameliorate glomerular basement membrane thickening and podocyte injury. In conclusion, carvedilol protects rats against streptozotocin-induced early diabetic nephropathy possibly, in part, through its antioxidant as well as anti-inflammatory activities, and ameliorating podocyte injury.

Mechanism of testicular protection of carvedilol in streptozotocin-induced diabetic rats.

AIMS: Male sub-fertility and infertility are major complications of diabetes mellitus. The non-selective ß-blocker carvedilol has been reported to have favorable effects on some of the diabetic complications based on its antioxidant and anti-apoptotic effects. This study aims to evaluate the possible testicular protective effect of carvedilol in streptozotocin (STZ)-induced diabetic rat model and its possible mechanisms. MATERIALS AND METHODS: Diabetes was induced by a single i.p. dose of 65 mg/kg of STZ. In parallel groups of diabetic rats, carvedilol in low and high doses (1 and 10 mg/kg/day orally) were administered for 4 weeks. Oxidative stress markers as reduced glutathione (GSH) and the product of lipid peroxidation; malondialdehyde (MDA) were evaluated in testicular homogenate. The level of expression of the apoptotic marker; caspase 3, was assessed using western blot, followed by densitometric analysis. RESULTS: Induction of diabetes caused distortion of histological normal testicular structure, with decrease (P < 0.05) in GSH and increase (P < 0.05) in MDA, as well as induction of caspase 3 expression. Carvedilol in low or high doses reverted diabetes-induced histological damage, restored antioxidant activity and ameliorated caspase 3 expression. CONCLUSION: Carvedilol confers testicular protection against diabetes-induced damage through antioxidant and anti-apoptotic mechanisms.

Curcumin ameliorates methotrexate-induced nephrotoxicity in rats.

Methotrexate is an effective anticancer and immunosuppressive agent. However, nephrotoxicity is one of the complications of its use. On the other hand, curcumin, a naturally occurring polyphenolic compound, is reported to have antioxidant and anti-inflammatory properties. Those two properties are likely to prevent methotrexate-induced nephrotoxicity. The aim of this study is to evaluate the possible protective effect of curcumin against methotrexate-induced nephrotoxicity and delineate various mechanism(s) underlies this effect in rats. Nephrotoxicity was induced in Wistar rats by intraperitoneal administration of methotrexate (7 mg/kg/day) for three consecutive days. Curcumin administration in methotrexate-intoxicated rats resulted in nephroprotective effects as evidenced by the significant decrease in levels of serum creatinine and urea as well as renal malondialdehyde, nitric oxide, and tumor necrosis factor- α with a concurrent increase in renal glutathione peroxidase and superoxide dismutase activities compared to nephrotoxic untreated rats. Additionally, immunohistochemical analysis demonstrated that curcumin treatment markedly reduced cyclooxygenase-2 expression. Histopathological examination confirmed the protective effects of curcumin. In conclusion, curcumin protected rats from methotrexate nephrotoxicity, at least in part, through its antioxidant and anti-inflammatory activities.