Magnetic fields ameliorates high-fat and high-protein diet-induced fatty liver in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the mechanism of the effect of low-frequency rotary constant magnetic field on high-fat and high-protein diet-induced fatty liver in rats.</p><p><b>METHODS</b>Fatty liver model was established in SD rats by feeding on a high-fat and high-protein diet daily. The enzyme activity changes in the serum and liver homogenate were detected at 10, 14, and 18 weeks, and the pathological changes of the liver were observed with optical and electron microscopy.</p><p><b>RESULTS</b>In magnetic field intervention group, the concentration of alanine aminotransferase and aspartate transaminase were significantly decreased, and the activity of lipoprotein lipase, hepatic lipase, superoxide dismutase and the concentration of malondialdehyde in the liver homogenate were significantly increased. Under optical microscope and electron microscope, the rats in the model group showed diffusive adipose degeneration in the hepatic cells with large lipid droplets, which became large vacuoles after fat extraction, indicating fatty necrosis. In magnetic field intervention group, remarkably smaller lipid droplets and lessened hepatic cell adipose degeneration were observed.</p><p><b>CONCLUSION</b>Low-frequency rotary constant magnetic field has beneficial effect on fat metabolism, leading to reduced lipid peroxidation and structural recovery of the degenerated hepatic cells.</p>

Morphological investigation of the protective effect of astragaloside preconditioning against ischemia-reperfusion lung injury in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the protective mechanisms of the astragaloside against ischemia-reperfusion lung injury in rats.</p><p><b>METHODS</b>Ischemia-reperfusion lung injury was induced in SD rats. Astragalus armour glucoside was dissolved in 1% of sodium carboxymethyl cellulose at different concentrations (8, 6, and 3 mg/ml) was intragastrically administered in the rats at the dose of 1 ml/100 g. Cellular and subcellular structural changes in the lung tissue were observed at the end of the experiment using optical and transmission electron microscope, with the wet/dry ratio of the lung tissue and myeloperoxidase (MPO) activity measured.</p><p><b>RESULTS</b>The wet/dry ratio and myeloperoxidase activity in the lung tissue were significantly higher in the model group than in the sham-operated group (P<0.05), and were significantly lowered by the treatment with astragalus armour glucoside at different doses (P<0.01 or 0.05), and the effect was especially obvious in rats receiving a moderate dose. Pulmonary capillary expansion, erythrocyte leakage and exudate in the alveolar space with obvious pathological changes in the type I and II epithelial cells were observed in model group. Pulmonary capillary expansion was reduced in rats treated with high, medium and low dose of Astragalus armour glucoside, and the medium dose group showed the most obvious effect, in which no edema fluid in the alveolar space or erythrocyte leakage was found with also reduced type II lung epithelial cell degranulation.</p><p><b>CONCLUSION</b>Astragaloside has obvious antioxidant effect in rats with ischemia-reperfusion lung injury, and a medium dose produces the best effect.</p>