The effects of pioglitazone and rosiglitazone on liver function in hypothyroid rats.

OBJECTIVES: This study aimed to investigate the antioxidant effect of rosiglitazone (ROG) and pioglitazone (POG) on oxidative damage and dysfunction of hepatic tissue in hypothyroid rats. METHODS: The male rats were classified into six groups: (1) Control; (2) Hypothyroid, (3) Hypothyroid-POG 10, (4) Hypothyroid-POG 20, (5) Hypothyroid-ROG 2, and (6) Hypothyroid-ROG 4. To induction hypothyroidism in rats, propylthiouracil (PTU) (0.05 %w/v) was added to drinking water. In groups 2-6, besides PTU, the rats were also intraperitoneal administrated with 10 or 20 mg/kg POG or 2 or 4 mg/kg ROG for six weeks. Finally, after deep anesthesia, the blood was collected to measure the serum biochemical markers and hepatic tissue was separated for biochemical oxidative stress markers. RESULTS: Administration of PTU significantly reduced serum thyroxin concentration, total thiol levels, activity of superoxide dismutase (SOD) and catalase (CAT) enzymes, and increased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (Alk-P) and malondialdehyde (MDA) in the liver. Additionally, our results showed that prescription of POG or ROG for six weeks to hypothyroid rats resulted in an improvement in liver dysfunction (decrease in serum levels of AST, ALT, and ALK-P) through reducing oxidative damage in hepatic tissue (increase in CAT, SOD, or total thiols and decrease in MDA levels). CONCLUSIONS: The findings of the present study presented that the IP administration of POG and ROG for six weeks improves liver dysfunction induced by hypothyroidism in juvenile rats by reducing oxidative damage.

Selenium prevented renal tissue damage in lipopolysaccharide-treated rats.

OBJECTIVES: Kidney diseases are one of the common diseases, which are one of the main causes of death in society and impose costs on the health system of the society. A growing body of evidence has well documented that inflammatory responses and oxidative damage play a significant role in the progress of various kidney diseases. METHODS: This study examined whether selenium (Sel) could prevent the detrimental influences of lipopolysaccharide (LPS) in rats. Four groups of Wistar rats were considered: control, LPS (1 mg/kg, i.p., for 14 days), LPS-Sel 1 (0.1 mg/kg, i.p., for 14 days), and LPS-Sel 2 (0.2 mg/kg, i.p., for 14 days). RESULTS: Sel treatment markedly attenuated oxidative stress damage in the kidney tissue in LPS-induced renal toxicity. Generally, the administration of Sel resulted in improved antioxidant indicators such as catalase (CAT) and superoxide dismutase (SOD) activities, or total thiol content, and decreased malondialdehyde (MDA) in the kidney tissue. It also decreased interleukin-6 in kidney homogenates. Furthermore, Se treatment significantly inhibited the elevation of serum biochemical markers of kidney function including serum, BUN, and creatinine. CONCLUSIONS: Based on the findings of the current study, it seems that the administration of Sel to LPS-treated rats improves renal function by reducing oxidative damage and inflammation in kidney tissue. However, more research is needed to reveal the accurate mechanisms for the effect of Sel on renal outcomes of LPS in human subjects.

The effect of Cinnamomum cassia extract on oxidative stress in the liver and kidney of STZ-induced diabetic rats.

OBJECTIVES: Many diabetes-related complications are caused by oxidative stress. In the current study, the protective effect of Cinnamomum cassia against diabetes-induced liver and kidney oxidative stress was evaluated. METHODS: The male Wistar rats (n=48) were randomly divided into six groups including; control group received 500 µL normal saline orally for 42 days. Diabetes groups received intraperitoneally (i.p.) streptozotocin (STZ) as single-dose (60 mg/kg, i.p.). Cinnamon extract (100, 200, 400 mg/kg) and metformin (300 mg/kg) were orally administered to diabetic rats for 42 days. After the experiment period, the animals were anesthetized and the liver and kidney tissues were quickly removed and restored for oxidative stress evaluation. The levels of malondialdehyde (MDA), total thiol content, glutathione (GSH), nitric oxide (NO) metabolites, as well as, superoxide dismutase (SOD) and catalase (CAT) activities were measured in kidney and liver tissue. RESULTS: The level of MDA, SOD, and CAT activities increased significantly, while the total thiol content, and NO production were significantly reduced in diabetic animals compared to the control group (from p<0.05 to p<0.001). Treatment with cinnamon extract significantly decreased the MDA level, as well as, SOD and CAT activities in the liver and kidney of diabetic rats (from p<0.05 to p<0.001). In the liver and kidney of cinnamon treated groups, GSH and total thiol contents and NO production were significantly higher than diabetic group (from p<0.05 to p<0.001). CONCLUSIONS: Cinnamon extract due to its potent antioxidant property could be effective in decrease of diabetes-induced oxidative stress that plays a major role in renal and hepatic complications.