Objective To investigate the effects of aerobic exercise on tau phosphorylation and PI3K/ Akt pathway in the hippocampus of obese rats,and provide some theoretical basis for physical activity improving obesity-related neurological disorders.Methods Male Sprague-Dawley rats aged 3 weeks were randomly assigned to either a high-fat or a normal diet protocol for 12 weeks.Animals submitted to the high-fat diet were further divided into two groups:a sedentary group (HF-Sed) and an exercise group (HF-Ex).The rats fed the normal diet were also divided into a sedentary group (ND-Sed)and an exercise group (ND-Ex).The rats in the HF-Ex and ND-Ex groups underwent a treadmill training for 8 weeks.Then the hippocampus was isolated at 48h after the last exercise.The protein and phosphorylation levels of tau,glycogen synthase kinase 3β (GSK3β),phosphoinositide 3-kinase (PI3K) and Akt were assayed using Western blotting.Results After 12 weeks of feeding,55％ of rats in the high-fat diet group reached the conditions for the obesity model.After 8 weeks of treadmill exercises,in the HF-Sed group the phosphorylation level of tau was significanlty higher than that in the ND-Sed group,while in the HF-Ex group that was significantly lower than the HF-Sed group.Moreover,in the HF-Sed group the phosphorylation level of GSK3β Ser9 was significantly lower,and the phosphorylation level of GSK3β Tyr216 was significantly higher than the ND-Sed group,indicating the activity of GSK3β was significantly higher than the ND-Sed group.However,after 8 weeks of treadmill exercise,in the HF-Ex group the phosphorylation level of GSK3β Ser9 was signfiicantly higher,and the phosphorylation level of GSK3β Tyr216 was signficanlty lower than the HF-Sed group,indicating significantly lower activity of GSK3β than the HF-Sed group.Then,in the HF-Sed group the protein levels of PI3K p110 and p85 subunits,and the phosphorylation levels of Akt Thr308 and Ser473 were significantly lower than those in the ND-Sed group,indicating inhibited activity of the PI3K/Akt pathway.However,in the HF-Ex group the protein levels of PI3K p110 and p85 subunits and the phosphorylation levels of Akt Thr308 and Ser473 were significanlty higher than those in the HF-Sed group,showing the activity of PI3K/Akt pathway was enhanced.Conclusion Obesity induces tau hyperphosphorylation in the rats hippocampus and long-term aerobic exercises can reduce tau hyperphosphorylation by increasing PI3K/Akt pathway activity and inhibiting GSK3β activity.It has a positive effect on delaying the formation of neurofibrillary tangles and improving obesity-related neurological disorders.

Wutou-Gancao herb-pair is extensively used to attenuate the toxicity and enhance the efficacy of aconite. In this study, potential synergic mechanism of the herb pair was investigated by utilizing multiple ap-proaches. In silico and in vitro Caco-2 cell models were applied to study the potential binding mode of bioactive ingredients existing in liquorice with P-glycoprotein (P-gp), as well as the inhibition effects on P-gp. Additionally, anti-inflammatory activity of aconitine (AC) combined with active ingredients of liquorice, as well as pharmacokinetic patterns of AC after co-administration was investigated. Anti-inflammatory effect of AC (1 mg/kg) in rats was enhanced in combination with bioactive ingredients of liquorice (10 mg/kg). In the meanwhile, the exposure of AC in vivo was altered, in terms of Cmax and AUC. For instance, the Cmax and AUC were increased to 1.9 and 1.3 folds, respectively, when used in combination with liquiritigenin. The in silico study revealed the potential binding mode with outward facing conformation of P-gp. The resulting data obtained from transport of rhodamine-123 (Rh-123) across Caco-2 cell monolayer further indicated that the function of P-gp was inhibited by chemicals in liquorice. The synergic effect was therefore proposed to be attributed to inhibition of P-gp by liquorice since AC has been demonstrated to be the substrate of P-gp. The resuls revealed that potential synergic mechanism of Wutou-Gancao herb-pair by inhibiting function of key efflux transporter P-gp to enhance the exposure of AC in systematic circulation, and further the anti-inflammatory effect, which helps clarify the compatibility rationale of these two herbs.

Objective In the present study, we investigated the effects of advanced oxidation protein products(AOPP) on reactive oxygen species(ROS) production in murine osteoblastic MC3T3-E1 cells by NADPH oxidase enzymes pathway. Methods Experiments were divided into three groups, including control group, rats albumin(RSA) group, and AOPP group. Different concentrations of AOPP were added to the osteoblastic MC3T3-E1 cells culture medium. The production of ROS in MC3T3-E1 cells was measured by the fluorescence intensity of intracellular fluoroprobe ( DCFD ) . In order to verify the effect of enzyme of the production of ROS, the specific inhibitors of corresponding enzymes were added in the MC3T3-E1 cells which were cultured in the medium with AOPP. Finally, western blot and immunofluorescence were used to observe the changes of NADPH oxidase enzymes subunits. Results Different concentrations of AOPP (50,100,200μg/ml) induced MC3T3-E1 cells to produce different amount of ROS. The higher concentrations of AOPP were added, the more ROS were produced. Furthermore,200μg/ml AOPP induced the maximum amount of ROS production(P<0. 05). Meanwhile, AOPP induced MC3T3-E1 cells to produce different amount of ROS with a time-dependent manner. The peak amount of ROS production in MC3T3-E1 cells was observed in 3h when AOPP were added (P<0. 05). In addition, when specific inhibitors of corresponding enzymes were added in the MC3T3-E1 cells, the production of ROS were significantly suppressed by C-SOD, DPI, and apocynin(P<0. 05). On the other hand, AOPP can up-regulate the expression of Nox4 protein of the MC3T3-E1 cells, which is one of the subunits of NADPH oxidase enzymes. Meanwhile, AOPP can also induce the membrane migration of p47phox subunit. Conclusion AOPP induces osteoblastic MC3T3-E1 cells to produce ROS by NADPH oxidase enzymes pathway, and which may be one of the pathogenesis of AOPP involved in osteoporosis.