thioacetamide and Hypertension

Toxic chemicals such as carbon tetrachloride and thioacetamide (TAA) are reported to induce hepato-nephrotoxicity. The potential protective outcome of the antidiabetic and pleiotropic drug metformin against TAA-induced chronic kidney disease in association with the modulation of AMP-activated protein kinase (AMPK), oxidative stress, inflammation, dyslipidemia, and systemic hypertension has not been investigated before. Therefore, 200 mg/kg TAA was injected (via the intraperitoneal route) in a model group of rats twice a week starting at week 3 for 8 weeks. The control rats were injected with the vehicle for the same period. The metformin-treated group received 200 mg/kg metformin daily for 10 weeks, beginning week 1, and received TAA injections with dosage and timing similar to those of the model group. All rats were culled at week 10. It was observed that TAA induced substantial renal injury, as demonstrated by significant kidney tissue damage and fibrosis, as well as augmented blood and kidney tissue levels of urea, creatinine, inflammation, oxidative stress, dyslipidemia, tissue inhibitor of metalloproteinases-1 (TIMP-1), and hypertension. TAA nephrotoxicity substantially inhibited the renal expression of phosphorylated AMPK. All these markers were significantly protected by metformin administration. In addition, a link between kidney fibrosis and these parameters was observed. Thus, metformin provides profound protection against TAA-induced kidney damage and fibrosis associated with the augmentation of the tissue protective enzyme AMPK and inhibition of oxidative stress, inflammation, the profibrogenic gene TIMP-1, dyslipidemia, and hypertension for a period of 10 weeks in rats.

Topics: AMP-Activated Protein Kinases; Animals; Down-Regulation; Dyslipidemias; Fibrosis; Hypertension; Inflammation; Liver; Liver Cirrhosis; Metformin; Oxidative Stress; Rats; Renal Insufficiency, Chronic; Thioacetamide; Tissue Inhibitor of Metalloproteinase-1; Up-Regulation

Chronic liver injury can lead to hepatic failure and the only available method of treatment would be liver transplantation. The link between inflammation (TNF-α), nuclear factor-kappa B (NF-kB), nitrosative stress (iNOS) and hypoxia-inducible factor-1α (HIF-1α) in thioacetamide (TAA) induced liver fibrosis, and hypertension with and without the incorporation of the anti-inflammatory and antioxidant resveratrol (RES) has not been investigated before. Consequently, we injected rats with either 200 mg/kg TAA for 8 weeks starting at week 2 (model group) or pretreated them before TAA injections with RES (20 mg/kg) for 2 weeks and continued them on RES and TAA until being culled at week 10 (protective group). In the model group, we documented the induction of hepatic fibrosis and upregulation of tumor necrosis factor-α (TNF-α), NF-kB, inducible nitric oxide synthase (iNOS), HIF-1α and the profibrotic biomarkers alpha-smooth muscle actin (α-SMA) and matrix metalloproteinase-9 (MMP-9) that was significantly (p ≤ 0.0014) ameliorated by RES. RES also significantly (p ≤ 0.0232) reduced triglycerides (TG), cholesterol (CHOL), very low-density lipoprotein (vLDL-C), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure, and heart rate (HR) induction by TAA. Also, a significant (p < 0.0001) positive correlation between TNF-α/NF-kB/iNOS/HIF-1α axis-mediated fibrosis and hypertension and liver injury biomarkers was observed. These findings suggest that in the hepatotoxic compound, TAA is associated with TNF-α/NF-kB/iNOS/HIF-1α-mediated fibrosis and hypertension, whilst being inhibited by RES.

Topics: Animals; Biomarkers; Chemical and Drug Induced Liver Injury, Chronic; Hypertension; Hypoxia-Inducible Factor 1, alpha Subunit; Liver; Liver Cirrhosis; NF-kappa B; Nitric Oxide Synthase Type II; Rats; Resveratrol; Thioacetamide; Tumor Necrosis Factor-alpha