Objective To observe the effects of tea polyphenols (TP) on cardiac function and myocardial ultrastructure in rats after repeated +10 Gz stress. Method Twenty four male Wistar rats were randomly divided into three groups (n=8 each): group A (control), group B (+10 Gz), group C (+Gz with TP). Group B and C were repeatedly exposed to +10 Gz (each for 30 s, onset rate about 0.5 G/s, 3 times/d with +1 Gz 1 min intervals, 3 d/wk, 4 weeks in total), but group A was only submitted to +1 Gz. TP(200 mg.kg-1) was given orally to group C about 1h prior to the +Gz experiment, and distilled water was given to group A and B.Function of isolated rat working hearts and myocardial ultrastructure were observed. Result A significant decrease of left ventricular systolic pressure (LVSP) and injury of myocardial structure in rats were demonstrated after repeated +10 Gz stress. But TP could remarkably elevate the LVSP and improve myocardial ultrastructural injury in +10Gz stressed rats. Conclusion These results indicated that repeated high G exposure may produce cardiac structural and functional injuries in rats which might be partly related to free radical metabolism; and antioxidant TP had significant protective effects on the hearts of +Gz stressed rats.

Aim To evaluate the antinociception of ω-SO3,a novel Omega-superfamily conotoxin,in rat formalin test.Methods Potency and duration of ω-SO3 antinociception compared with morphine were investigated in rat formalin test after acute intrathecal administration.Development of tolerance or cross tolerance to analgesia of ω-SO3 and morphine was tested in formalin test after chronic intrathecal administration.Locomotor activity of rat after acute intrathecal administration was tested to evaluate possible central side effects.Results In rat formalin test after intrathecal bolus injection,ω-SO3 produced dose-and time-dependent antinociception by suppressing acute(ED_(50),1.79 ng·g~(-1))and tonic phases(ED_(50),0.41 ng·g~(-1)),which was approximately 10-fold potency and twice longer-acting of morphine in blocking tonic phase responses.After repeated intrathecal injections twice daily for 5 consecutive days,ω-SO3 produced analgesia without loss of potency whereas morphine produced analgesia tolerance in rat formalin test;further,ω-SO3 still produced potent analgesia in morphine-tolerant rats.No changes in motor function were seen in rats receiving above antinociceptive doses.Conclusion sNovel ω-SO3 produces potent and long-acting spinal antinociception without observable motor dysfunction and after chronic intrathecal administration.ω-SO3 produces neither tolerance nor cross-tolerance to morphine analgesia.

OBJECTIVE AMPK activator,act as exer-cise mimetics,effective in preventing or ameliorating met-abolic diseases,including obesity and diabetes.Systemic activating of AMPK represents an important therapeutic strategy to treat metabolic diseases.However,whether far-infrared(FIR)hyperthermia therapy could be used as exercise mimetic to realize wide-ranging metabolic regu-lation,and its underling mechanisms remain unclear.METHODS The mice were subjected to hyperthermia in the FIR chamber(30±1)℃for 14 d.Exercise endurance was determined using a treadmill.Blood flow were mea-sured by the laser speckle contrast imaging.Combina-tion of microbiomic and metabolomic analysis,diversity of microbiota and metabolic profiling in muscle were detected.The microbiota disorder model via treatment with different cocktails of antibiotics(ABX).RESULTS The material characterization shows that the graphene synthesized by chemical vapour deposition(CVD)is dif-ferent from carbon fi ber,with single-layer structure and high electrothermal transform efficiency.The emission spectra generated by graphene-FIR device would maxi-mize matching those adsorbed by tissues(≈8.0 μm).Gra-phene-FIR improves core and epidermal temperature,and increases blood flow in femoral muscle and abdo-men.The diversity of gut microbiota was increased by graphene-FIR exposure.Graphene-FIR reduced the bac-teroidetes/firmicutes(B/F)ratio and increased the abun-dance of short-chain fatty acids(SCFA)-producing bac-teria,including Allobaculum,Blautia and Anaerostipes.Additionally,graphene-FIR stimulated the expression of SCFAs-sensing receptor(GPR 43),p-AMPK Thr172 and GLUT4,and increased the AMP/ATP ratio,thus enhanc-ing muscle glucose uptake.Metabolomic analyses revealed the significant changes in 25 metabolites,with twenty increased(eg.creatinine and phosphate)and five decreased(eg.lactic acid),and the marked impact of five metabolic pathways,including galactose metabo-lism,glycolysis,gluconeogenesis,fatty acid biosynthesis,butanoate metabolism,pyruvate metabolism.Further-more,a microbiota disorder model also demonstrates that the graphene-FIR effectively restore the exercise endurance with enhanced p-AMPK and GLUT4.CON-CLUSION Our results provide convincing evidence that graphene-based FIR therapy promoted exercise capacity and glucose metabolism via AMPK in gut-muscle axis.These novel insights into graphene-FIR therapy suggest a potential as an exercise mimetic for the treatment of metabolic disease in clinical.