[Impact of electroacupuncture on liver lipid metabolism and hepatic Sirt1 and PPARγ expression in abdominal obese rats].

OBJECTIVE: To observe the impact of electroacupuncture (EA) on liver lipid metabolism and expression of hepatic sirtuin 1(Sirt1) and peroxisome proliferator activated receptor γ(PPARγ) of abdominal obese rats induced by high-fat diet. METHODS: Eighteen male SD rats were divided into blank control, model and EA groups (n＝6 per group). The abdominal obesity model was established by feeding the rats with high-fat diet for 12 weeks. EA (2 Hz/15 Hz, 1.5 mA) was applied to bilateral "Daimai"(GB26) for 20 min every time, once every other day for 8 weeks. Rats of the model group were also restrained for 20 min. The body mass and abdominal circumference were measured every week, and the contents of serum cholesterol (TC), triglyceride (TG), alanine transaminase (ALT), aspartate aminotransferase (AST) were detected by using an automated biochemical analyzer. Histopathological changes of the liver tissues were observed under microscope after oil red "O" staining. The expression of hepatic Sirt1 and PPARγ mRNAs and proteins were detected using quantitative real time PCR and Western blot, separately. RESULTS: After modeling, the body weight and abdominal circumference, and serum TC, TG, ALT and AST contents, and expression of hepatic PPARγ mRNA and protein were significantly increased (P<0.001, P<0.01, P<0.05), and the expression levels of hepatic Sirt1 mRNA and protein obviously down-regulated (P<0.05, P<0.01) in the model group. Following EA intervention, the increased body weight and abdominal circumference, and serum TC, TG, ALT and AST contents, and hepatic PPARγ mRNA and protein expression were remarkably suppressed (P<0.05, P<0.01), and the decreased hepatic Sirt1 mRNA and protein were remarkably up-regulated (P<0.001，P<0.05). The lipid droplets in hepatocytes were reduced in the EA group relevant to the model group. CONCLUSION: EA intervention can significantly improve the liver lipid metabolism of abdominal obese rats, which is possibly related with its effect in up-regulating the expression of hepatic Sirt1 mRNA and protein, and in down-regulating the expression of hepatic PPARγ mRNA and protein.

[Acupuncture improves hepatic lipid metabolism by suppressing oxidative stress in obese nonalcoholic fatty liver disease rats].

OBJECTIVE: To investigate the effect of acupuncture of "Daimai"(GB26) on abdominal fat accumulation, lipid metabolism and hepatic oxidative stress in abdominal obese non-alcoholic fatty liver disease (NAFLD) rats. METHODS: male SD rats were divided into 3 groups: normal diet (normal, n＝8), high fat diet control (model) and acupuncture (n＝8/group in the latter 2 groups). The abdominal obese NAFLD model was established by feeding the rats with high fat diet for 12 weeks. EA (2 Hz/15 Hz, 1.5 mA) was applied to bilateral GB26 for 20 min, once every other day for 8 weeks. Rats of the model group were also restrained for 20 min as those in the EA group. The body mass and abdominal circumference were measured weekly, the isolated adipose tissues around the bilateral kidney and epididymis and the fresh liver were weighed. The contents of serum cholesterol (TC), triglyceride (TG), alanine transaminase (ALT), glutamic oxaloacetic aminotransferase (AST) were detected by using an automatic biochemical analyzer. The abdominal visceral fat distribution was acquired by CT scanning. The oxidative stress indexes of the homogenated liver tissues, such as malondialdehyde (MDA) was assayed using sodium thiobarbital (TBA) method, and the activity of total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-PX) were assayed by using hydroxylamine method and colorimetric method respectively. The histopathological changes of the liver were observed after staining with hematoxylin-eosin (HE). RESULTS: Following modeling, the body mass and waist circumference, visceral fat weight of bilateral kidneys and testis (visceral fat weight), liver weight, serum ALT, AST, TG and TC and liver MDA contents, were significantly higher in the model group (P<0.001，P<0.05), while hepatic T-SOD and GSH-PX activity was considerably lower in the model group than those in the normal group (P<0.001). After acupuncture intervention, the levels of all the above-mentioned indexes (modeling induced both increase and decrease) were reversed relevant to the model group (P<0.05, P<0.01). The results of CT scanning showed that the fat accumulation area in the abdomen was 8.67 cm2, 18.51 cm2 and 13.75 cm2 in the normal, model and acupuncture groups, respectively, presenting a decrease after acupuncture. H．E. staining displayed that the degree of hepatic steatosis (including vague hepatic lobule boundary, disordered arrangement of hepatic cord, hepatocellular swelling, diffuse fatty degeneration, unequal-sized lipid droplets in the hepatocytes, nucleus excursion and dissolution after modeling) was improved after acupuncture. CONCLUSION: Acupuncture can reduce body weight and abdominal fat accumulation in abdominal obese NAFLD rats, which may be related to its effects in inhibiting oxidative stress (lowering MDA level and increasing the activity of T-SOD and GSH-PX) and improving hepatic lipid metabolism.

Influence of Iron Supplementation on DMT1 (IRE)-induced Transport of Lead by Brain Barrier Systems in vivo.

OBJECTIVE: To investigate the potential involvement of DMT1 (IRE) protein in the brain vascular system in vivo during Pb exposure. METHODS: Three groups of male Sprague-Dawley rats were exposed to Pb in drinking water, among which two groups were concurrently administered by oral gavage once every other day as the low and high Fe treatment group, respectively, for 6 weeks. At the same time, the group only supplied with high Fe was also set as a reference. The animals were decapitated, then brain capillary-rich fraction was isolate from cerebral cortex. Western blot method was used to identify protein expression, and RT-PCR to detect the change of the mRNA. RESULTS: Pb exposure significantly increased Pb concentrations in cerebral cortex. Low Fe dose significantly reduced the cortex Pb levels, However, high Fe dose increased the cortex Pb levels. Interestingly, changes of DMT1 (IRE) protein in brain capillary-rich fraction were highly related to the Pb level, but those of DMT1 (IRE) mRNA were not significantly different. Moreover, the consistent changes in the levels of p-ERK1/2 or IRP1 with the changes in the levels of DMT1 (IRE). CONCLUSION: These results suggest that Pb is transported into the brain through DMT1 (IRE), and the ERK MAPK pathway is involved in DMT1 (IRE)-mediated transport regulation in brain vascular system in vivo.