Topical atorvastatin ameliorates 12-O-tetradecanoylphorbol-13-acetate induced skin inflammation by reducing cutaneous cytokine levels and NF-κB activation.

Atorvastatin is a 3-hydroxy-3-methylglutaryl coenzyme-A reductase inhibitor used in the treatment of atherosclerosis and dyslipidemia. Studies have evaluated the utility of statins in the treatment of skin inflammation but with varied results. In the present study, we investigated the effect of atorvastatin on TNF-α release and keratinocyte proliferation in vitro and in acute and chronic 12-O-tetradecanoylphorbol-13-acetate (TPA) induced skin inflammation in vivo. Atorvastatin significantly inhibited lipopolysacharide induced TNF-α release in THP-1 cells and keratinocyte proliferation in HaCaT cells. In an acute study, topical atorvastatin showed dose dependent reduction in TPA induced skin inflammation with highest efficacy observed at 500 µg/ear dose. In chronic study, topical atorvastatin significantly reduced TPA induced ear thickness, ear weight, cutaneous cytokines, MPO activity and improved histopathological features comparable to that of dexamethasone. Atorvastatin also inhibited TPA stimulated NF-κB activation in mouse ear. In conclusion, our results suggest that atorvastatin ameliorates TPA induced skin inflammation in mice at least in part, due to inhibition of cytokine release and NF-κB activation and may be beneficial for the treatment skin inflammation like psoriasis.

A novel animal model of metabolic syndrome with non-alcoholic fatty liver disease and skin inflammation.

CONTEXT: Metabolic syndrome and non-alcoholic fatty liver disease (NAFLD) are the emerging co-morbidities of skin inflammation. Occurrence of skin inflammation such as psoriasis is substantially higher in NAFLD patients than normal. Currently, there are no animal models to study the interaction between these co-morbidities. OBJECTIVE: The present study seeks to develop a simple mouse model of NAFLD-enhanced skin inflammation and to study the effect of NAFLD on different parameters of skin inflammation. MATERIALS AND METHOD: Metabolic syndrome and NAFLD were induced in C57BL/6 mice by feeding high-fat diet (HFD, 60% kcal) and high fructose liquid (HFL, 40% kcal) in drinking water. Skin inflammation was induced by repeated application of oxazolone (1% sensitization and repeated 0.5% challenge) in both normal and NAFLD mice and various parameters of skin inflammation and NAFLD were measured. RESULTS: HFD and HFL diet induced obesity, hyperglycemia, hyperinsulinemia, and histological features of NAFLD in mice. Oxazolone challenge significantly increased ear thickness, ear weight, MPO activity, NF-κB activity, and histological features of skin inflammation in NAFLD mice as compared with normal mice. Overall, induction of oxazolone-induced skin inflammation was more prominent in NAFLD mice than normal mice. Hence, HFD and HFL diet followed by topical oxazolone application develops metabolic syndrome, NAFLD, and enhanced skin inflammation in mice. DISCUSSION AND CONCLUSION: This simple model can be utilized to evaluate a therapeutic strategy for the treatment of metabolic syndrome and NAFLD with skin inflammation and also to understand the nexus between these co-morbidities.

Combination of vildagliptin and rosiglitazone ameliorates nonalcoholic fatty liver disease in C57BL/6 mice.

OBJECTIVES: To evaluate the effect of vildagliptin alone and in combination with metformin or rosiglitazone on murine hepatic steatosis in diet-induced nonalcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: Male C57BL/6 mice were fed with high fat diet (60 Kcal %) and fructose (40%) in drinking water for 60 days to induce NAFLD. After the induction period, animals were divided into different groups and treated with vildagliptin (10 mg/kg), metformin (350 mg/kg), rosiglitazone (10 mg/kg), vildagliptin (10 mg/kg) + metformin (350 mg/kg), or vildagliptin (10 mg/kg) + rosiglitazone (10 mg/kg) orally for 28 days. Following parameters were measured: body weight, food intake, plasma glucose, triglyceride (TG), total cholesterol, liver function tests, and liver TG. Liver histopathology was also examined. RESULTS: Oral administration of vildagliptin and rosiglitazone in combination showed a significant reduction in fasting plasma glucose, hepatic steatosis, and liver TGs. While other treatments showed less or no improvement in the measured parameters. CONCLUSIONS: These preliminary results demonstrate that administration of vildagliptin in combination with rosiglitazone could be a promising therapeutic strategy for the treatment of NAFLD.