It is known that excessive sympathetic activity and oxidative stress are enhanced in obesity. This study aimed to clarify whether exercise training (ET) attenuates sympathetic activation and oxidative stress in obesity. The obesity was induced by high-fat diet (HFD) for 12 weeks. Male Sprague-Dawley rats were assigned to four groups: regular diet (RD) plus sedentary (RD-S), RD plus ET (RD-ET), HFD plus sedentary (HFD-S), and HFD plus ET (HFD-ET). The rats in RD-ET and HFD-ET groups were trained on a motorized treadmill for 60 min/day, five days/week for 8 weeks. The sympathetic activity was evaluated by the plasma norepinephrine (NE) level. The superoxide anion, malondialdehyde and F2-isoprostanes levels in serum and muscles were measured to evaluate oxidative stress. The ET prevented the increases in the body weight, arterial pressure and white adipose tissue mass in HFD rats. The NE level in plasma and oxidative stress related parameters got lower in HFD-ET group compared with HFD-S group. We have found decreased mRNA and protein levels of toll-like receptor (TLR)-2 and TLR-4 by ET in HFD rats. These findings suggest that ET may be effective for attenuating sympathetic activation and oxidative stress in diet-induced obesity.

ABSTRACT. The objective of this study was to observe the protective effect of the n-butyl alcohol phase of Toona sinensis seed extract on the kidneys of diabetic nephropathy (DN) rats and its preliminary mechanism. Male wistar rats were administered a normal or high-fat diet for 1 month. DN rats were divided into a model group and a petroleum ether phase of T. sinensis seed extract intervention group. The intervention group was administered 5 mg·100 g -1 ·day -1 extract. After treatment for 10 weeks, the rats were sacrificed and blood samples and the renal cortex were collected. Biochemical indicators in the serum and renal indices were assessed. Pathological changes of the renal tissues were also determined. Changes in the renal structure and protein levels were detected. Compared with the normal group, the blood glucose, urinary albumin, renal index, and oxidative stress index were sharply increased in the model group. The protein levels of TGF-b1, collagen IV, and connective tissue growth factor (CTGF) were increased. Compared with the model group, the n-butyl alcohol phase of T. sinensis seed extract significantly reduced the blood glucose, urinary albumin, renal index, oxidative stress index, serum creatinine, and urea nitrogen levels. The renal pathology abnormality was improved in DN rats. The protein levels of TGF-b1, collagen IV, and CTGF were increased. The expression of TGF-b1, collagen IV, and CTGF decreased. In conclusion, the n-butyl alcohol phase of T. sinensis seed extract has protective effects on DN rats via the inhibition of oxidative stress and protein expression of TGF-b1, collagen IV, and CTGF.