Attenuating effects of allantoin on oxidative stress in a mouse model of nonalcoholic steatohepatitis: role of SIRT1/Nrf2 pathway

BACKGROUND AND PURPOSE

Nonalcoholic steatohepatitis (NASH) is considered a common and serious liver disease, which develops into cirrhosis, fibrosis, and even hepatocellular carcinoma. Oxidative stress is identified as an important factor in the induction and promotion of NASH. Allantoin is a natural and safe compound and has notable effects on lipid metabolism, inflammation, and oxidative stress. Therefore, this study was aimed to assess the role of allantoin on the oxidative stress and SIRT1/Nrf2 pathway in a mouse model of NASH.

EXPERIMENTAL APPROACH

C57/BL6 male mice received saline and allantoin (saline as the control and allantoin as the positive control groups). NASH was induced by a methionine-choline deficient diet (MCD). In the NASH-allantoin (NASH-Alla) group, allantoin was injected for 4 weeks in the mice feeding on an MCD diet. Afterward, histopathological, serum, oxidative stress, and western blot evaluations were performed.

FINDINGS/RESULTS

We found NASH provided hepatic lipid accumulation and inflammation. Superoxide dismutase (SOD) and glutathione (GSH) levels decreased, lipid peroxidation increased, and the expression of SIRT1 and Nrf2 downregulated. However, allantoin-treatment decreased serum cholesterol, ALT, and AST. Liver steatosis and inflammation were improved. Protein expression of SIRT1 and Nrf2 were upregulated and SOD, CAT, and GSH levels increased and lipid peroxidation decreased.

CONCLUSION AND IMPLICATIONS

It seems that the antioxidant effects of allantoin might have resulted from the activation of SIRT1/Nrf2 pathway and increase of cellular antioxidant power.

A pilot double-blind randomised placebo-controlled trial of the effects of fixed-dose combination therapy ('polypill') on cardiovascular risk factors

AIM

Our objective was to investigate the effects and tolerability of fixed-dose combination therapy on blood pressure and LDL in adults without elevated blood pressure or lipid levels.

METHODS

This was a double-blind randomised placebo-controlled trial in residents of Kalaleh, Golestan, Iran. Following an 8-week placebo run-in period, 475 participants, aged 50 to 79 years, without cardiovascular disease, hypertension or hyperlipidaemia were randomised to fixed-dose combination therapy with aspirin 81 mg, enalapril 2.5 mg, atorvastatin 20 mg and hydrochlorothiazide 12.5 mg (polypill) or placebo for a period of 12 months. The primary outcomes were changes in LDL-cholesterol, systolic and diastolic blood pressure and adverse reactions. Analysis was by intention-to-treat basis.

RESULTS

At baseline, there were differences in systolic blood pressure (6 mmHg). Taking account of baseline differences, at 12 months, polypill was associated with statistically significant reductions in blood pressure (4.5/1.6 mmHg) and LDL-cholesterol (0.46 mmol/l). The study drug was well tolerated, but resulted in the modest reductions in blood pressure and lipid levels.

CONCLUSION

The effects of the polypill on blood pressure and lipid levels were less than anticipated, raising questions about the reliability of the reported compliance. There is a case for a fully powered trial of a polypill for the prevention of cardiovascular disease.

Esophageal cancer in Iran

Esophageal cancer is among the 10 most frequent cancers in the world. Iran is one of the known areas with a high incidence of esophageal cancer. Most of the patients in Iran have been reported from the north and northeast regions of the country. In one survey by the Iran Cancer Institute, 9% of all cancers and 27% of gastrointestinal cancers were esophageal carcinoma. The male to female ratio was 1.7/1. The distal portion of the esophagus is involved more often than other parts. Consumption of wheat flour, exposure to residues from opium pipes, drinking hot tea, and chewing nass (a mixture of tobacco, lime, ash, and other ingredients) are the suspect etiologic agents for esophageal cancer in Iran. Dysphagia, weight loss, anorexia, abdominal pain, and odynophagia are the common symptoms and signs of Iranian patients with esophageal cancer. For clinical staging, chest computed tomographic scanning is performed. Adenocarcinoma of the esophagus is not as common in Iran as in western countries. Public education, nutritional support, and eradication of opium addiction may decrease the morbidity and mortality that result from esophageal cancer. Surgery has traditionally been the mainstay of esophageal cancer treatment in Iran. Radiotherapy is mainly used postoperatively. The usual combination chemotherapy regimen is cisplatin plus flurouracil (5-Fu). Semin Oncol 28:153-157.