PO-003 Effect of C2C12 Myotubes Function after Electrical Stimulation at Different Time

Objective To study the effect of different time of electrical stimulation on C2C12 myotubes function, and further explore its molecular mechanism. Methods An electrical stimulation was given 7 days after C2C12 myotubes differentiation, of which intensity was 30ms, 3Hz, and the stimulation time was 60mins, 120mins, and 180mins, respectively. A total of four experimental groups, including Con (control group), E60 (60 mins group), E120and E180. Microscope was used to observe the muscular myotubes form; Kits were to detect MDA and ROS; Western blot was used to detect the expression of autophagy proteins and mechanism proteins, including PGC1, p-ULK, SIRT1 and SIRT3. Results Compared with the control group, MDA, ROS, SIRT3 increased significantly in E60 (p<0.05), p-ULK and PGC1 increased significantly (p<0.01), SIRT1 decreased significantly (p<0.05). In E120, MDA、ROS、SIRT3 and PGC1 increased significantly (p<0.01), SOD decreased significantly (p<0.05). In E180, MDA and ROS increased significantly (p<0.01), SOD decreased significantly (p<0.01). Conclusions Moderate electrical stimulation can significantly activate oxidative stress, and further promote SIRT3, PGC1 and p-ULK expression, while excessive stimulation has the opposite effects.

PO-201 Aging attenuates the effect of aerobic capacity in muscle and serum metabolic profile but not in white adipose tissue

Objective Aerobic capacity is a quantitative predictor of the morbidity and mortality in many diverse patient populations. While aging is the main factor affecting aerobic capacity. The present study aimed to assess the effect of aerobic capacity and aging on metabolic profile in rats and to investigate the metabolic interactions between white adipose tissue (WAT), muscle and serum. Methods In this study, we used rat models that were selectively bred to differ in maximal running capacity (High capacity runners (HCR) and Low capacity runners (LCR)). Part of the rats were sacrificed after 9 months and the rest at 21 months. The effect of aerobic capacity on metabolic profile was assessed from 9 months old young rats (HCR-Y and LCR-Y), while the effect of aging on the metabolic profile in different capacity rats was determined comparing 9 months to 21 months old rats (HCR-O and LCR-O). Nuclear magnetic resonance (NMR) spectroscopy was performed to detect the metabolomics of WAT, muscle and serum. Partial least-squares-discriminant analysis (PLS-DA) was used for pattern recognition between HCR-Y and LCR-Y and between HCR-O and LCR-O. Metabolites with variable influence on projection (VIP) >1.0 and p<0.05 were classified as significantly different metabolites between groups. Spearman correlation was used to assess the metabolic interactions between white adipose tissue (WAT), muscle and serum. Results HCR-Y rats had significantly higher skeletal muscle mass-to-body mass ratio (p<0.001), while lower body mass (p<0.001), fat mass (p<0.001), skeletal muscle mass (p=0.035) and fat mass to body mass ratio (p=0.004) than LCR-Y rats. The running capacity of HCR-Y rats was 132.7% (best running speed) better than LCR-Y rats (p<0.001). However, with age, the difference between body compositions between the two capacity groups became insignificant. HCR-O only had significantly lower body mass than the LCR-O (p=0.02). Running capacity (p=0.06) was 86.4% (best running speed) higher in the HCR-O rats than that of the LCR-O rats. PLS-DA revealed marked effects of aerobic capacity on metabolic profile in all three tissue types between HCR-Y and LCR-Y. The metabolic profile classification and prediction was best (i.e. sharper) in muscle than in WAT and serum. In addition, muscle and serum contained more significantly different metabolites than WAT in HCR-Y than in LCR-Y. Pathway analysis of the significantly different metabolites between HCR-Y and LCR-Y revealed that all the pathways belong to the lipid metabolism and amino acid metabolism in muscle while in serum it is only amino acid metabolism. However, in the case of the old groups, the PLS-DA gave reversed results. It revealed that WAT performed best in terms of classification and prediction of metabolites between HCR-O and LCR-O and had the most significantly different metabolites out of the three tissue types. The significantly different metabolites’ pathways belong to lipid metabolism in WAT. When assessing the metabolic interaction between different tissue types, all significantly different metabolites between HCR and LCR rats in young and old groups were moderately or strongly correlated (Spearman correlation between 0.45-0.9) with one or more metabolites in any of the three tissues. Conclusions In this study, we assessed the metabolic profile and body composition of WAT, muscle and serum in young and old rats with different aerobic capacities. We found that aerobic capacity greatly impacts body composition and the metabolic profile in muscle and serum in young rats, however the impact is attenuated with age. In addition, it is aging and not aerobic capacity that had the most influence on WAT metabolites. This suggest that WAT has more important role in aging process than previously assumed.

PO-101 Inhibition of Aerobic Exercise on PKC/CaV1.2 pathway enhanced the function of vascular smooth muscle in hypertension

Objective The purpose of this study was to investigate the effects of aerobic exercise on PKC/CaV1.2 pathway in mesenteric arterial smooth muscle from spontaneously hypertensive rats (SHRs) Methods Twelve-week-old male normotensive Wistar–Kyoto (WKY) rats and SHRs were randomly assigned to sedentary groups (SHR-SED, WKY-SED) and exercise training groups (SHR-EX, WKY-EX). Exercise groups were performed an 8-week moderate-intensity treadmill running. After 8 weeks, vascular contractility of mesenteric arteries was measured. Vascular smooth muscle cells (VSMCs) were obtained with an enzymatic isolation method. CaV1.2 channel currents were examined by using whole-cell patch clamp recording technique. Results 1) Body weight and systolic blood pressure (SBP) in both WKY-EX and SHR-EX were significantly lower than those of their sedentary counterparts (both P＜0.05). Body weight in SHR-SED was remarkably lower than WKY-SED (P＜0.05), while SBP was much higher than WKY-SED (P＜0.05). 2) PDBu (PKC activator) elicited a tension increase, and Gö6976 (PKC inhibitor) induced vasodilation. Both the responses of PDBu and Gö6976 in SHR-SED were notably increased compared with WKY-SED (both P＜0.05), however, exercise training significantly suppressed these increases (both P＜0.05). 3) Nifedipine (CaV1.2 inhibitor) induced vasodilation. Response to nifedipine in SHR-SED was more sensitive than both SHR-EX and WKY-SED (both P＜0.05). 4). The current density of SHR-SED and WKY-EX exhibited an increase compared to the WKY-SED (both P＜0.05), and the current density of the SHR-EX decreased obviously in contrast with SHR-SED (P＜0.05). Besides, PDBu enlarged current density of all the groups, while Gö6976 decreased current density. The increase or decrease amplitude in SHR-SED was significantly higher than WKY-SED (both P＜0.05), whereas exercise training markedly inhibited those responses (both P＜0.05). Conclusions Aerobic exercise efficiently prevents the upregulation of PKC/CaV1.2 pathway in hypertension, and enhances the function of vascular smooth muscle.

PO-184 Effects of resistance training and aerobic training on Fibronectin of Skeletal Muscle Extracellular Matrix and Satellite Cell in Aging Mice

Objective To investigate the effects of resistance and aerobic training on the content of fibronectin in skeletal muscle extracellular matrix and satellite cell in 9-month-old BALB/c mice, and then explore the effect of fibronectin content change on satellite cell and its intrinsic mechanism, which will provide a new research perspective and theoretical evidence for delaying sarcopenia. Methods 27 one-month-old BALB / c mice of SPF grade were purchased and fed for natural aging. At 9 months of age, the mice were divided into three groups randomly. Group R was resistance exercise training group (n=9), group A was aerobic exercise training group (n=9), and group C was control group (n=9). The load ladder model for resistance training in group R, the pyramid training program for 9 week training, 5 sets of load ladder training every time. 2 min for rest between sets, 1 min for rest between repetitions, 3 times a week. The treadmill training for aerobic training in group A for 9 weeks, the speed of 0.8km/h, 40min every time, 3 times a week. There is no training in group C. During the training, mouse grip strength was tested by the BIOSEB grip instrument once a week. After exercise intervention, the blood of mice was taken from the eyeball, and the gastrocnemius muscles were removed and placed in -80℃ temperature refrigerator to be freezed for tested . Immunofluorescence was used to detect FN and Pax7; The Real-time PCR was used to detect mRNA of FN, Sdc4, Fzd7, Wnt7a, c-Jun, Pax7; Western Blotting was used to detect the FN, sdc4, Fzd7, Wnt7a, c-Jun, p-c-Jun, Pax7 protein content. Results (1) Body weight, grip strength and skeletal muscle mass of mice: The body weight of group C and group R were significantly decreased after 9 weeks to compared with group A (P <0.05; P <0.05). The grip strength of group R and A was significantly increased in the ninth week to compared with group C, (P <0.01; P <0.05); The grip strength of group R and A in the ninth week were significantly higher than that in the first week (P <0.01; P <0.01)； (2) FN in skeletal muscle extracellular matrix and it’s receptor Sdc4: The integrated optical density (IOD) of FN in group R was higher than that in group C and group A, but there was no significant difference among the three groups. The FN mRNA in group R was significantly increased to compared with group A (P<0.05). The FN protein content in group R was significantly increased to compared with group C and group A (P <0.01; P <0.01). There was no significant difference in the expression of Sdc4 mRNA in gastrocnemius muscle among the three groups. Compared with group C, the Sdc4 protein content was significantly down-regulated in both group R and group A (P<0.01; P<0.05). (3) Wnt7a/PCP signaling pathway: The Wnt7a mRNA and Wnt7a protein content in the gastrocnemius muscle of group R were significantly increased to compared with group C (P<0.05; P<0.01)). Compared with group A, Wnt7a protein content in group R was also significantly increased (P<0.05). There was no significant difference in Fzd7 mRNA in gastrocnemius muscle among the three groups; but the Fzd7 protein content in group R was significantly increased to compared with group A (P<0.05). The c-Jun mRNA in group R was significantly increased to compared with group C and A (P<0.05; P< 0.05). The content of c-Jun protein in group R was significantly increased to compared with group C and group A (P<0.01; P<0.01). The content of p-c-Jun protein in group R was significantly increased to compared with group C (P<0.05). (4) Pax7 : The number of Pax7 positive cells in group R was higher than that in group C and group A, but there was no significant difference among the three groups. Pax7 mRNA in group R and group A were significantly lower than that in group C (P<0.05; P<0.01), but Pax7 protein content in group R was significantly higher than group C and group A (P <0.05; P <0.05) Conclusions (1) Exercise can improve muscle strength of aging mice. (2) Resistance training can promote FN in skeletal muscle extracellular matrix and improve skeletal muscle extracellular matrix components of aging mice. (3) Resistance exercise training can promote Pax7 expression through the increase of FN and up-regulation of Wnt7a / PCP signaling pathway, thus make it possible for satellite cell proliferation.

PO-063 Exercise alleviates insulin resistance by regulating MG53 and IR/IRS/AKT/mTOR signaling in db/db mice skeletal muscle

Objective In the current study, we aim to investigate whether 12-week treadmill exercise alleviates insulin resistance and muscle atrophy, and to explore whether MG53 along with IR/IRS/AKT/mTOR cascade play a role in the physiopathological changes of db/db mice. Methods 20 db/db mice and 20 age-matched non-diabetic m/m mice were assigned to 4 groups as MC (m/m control) group, ME (m/m exercise) group, DC (db/db control) group and DE (db/db exercise) group. After an intervention of treadmill exercise of moderate intensity for 12 weeks, glucose and insulin tolerance tests, insulin resistance index (HOMA-IR, homeostasis model assessment of insulin resistance) and lipid metabolic profile were determined using blood samples. Skeletal muscles were utilized for determination of cross-sectional area (CSA), protein level detection of MG53 and insulin signaling pathway. Results Compared with MC mice, the AUC (areas under curve) of IPGTT (intraperitoneal glucose tolerance test) and IPITT (intraperitoneal insulin tolerance test) as well as HOMA-IR were significantly increased, and lipid parameters (serum triglyceride and total cholesterol) increased significantly in DC group. The upregulation of MG53 protein in different skeletal muscles (quadriceps, gastrocnemius and soleus muscle) could be observed in DC mice. Phosphorylated proteins of IR-β (β subunit of insulin receptor), IRS1, AKT (protein kinase B), mTOR (mammalian target of rapamycin), p70S6k and S6 ribosomal protein after acute insulin stimulation were downregulated with significance, whereas no significant difference was found in total protein levels of IR-β and AKT except IRS1 in DC group. The results of AUC of IPGTT and IPITT, HOMA-IR and serum lipid parameters in DE group were significantly decreased compared with DC group. 12-week moderate exercise was sufficient to downregulate the expression of MG53 in skeletal muscles of diabetic db/db mice. In addition, treadmill exercise-induced improvement of insulin signal transduction and insulin-dependent protein synthesis may partially account for the heavier muscle mass and larger muscle size. Conclusions In summary, insulin resistance and muscle atrophy of diabetic db/db mice could be effectively attenuated by 12-week moderate treadmill exercise by regulating MG53, MG53-mediated ubiquitin-dependent degradation of IRS1 and insulin signaling transduction.

PO-306 The effect of four weeks hypoxic resistance training on myostatin and follistatin expression in skeletal muscle of rats

Objective Loss of skeletal muscle weight is a common phenomenon in hypoxic environment. It has been recognized that resistance training can reduce hypoxia-induced skeletal muscle atrophy, but its molecular mechanism is still unclear. Myostatin is a major factor that inhibits muscle growth and differentiation, and Follistatin can inhibit Myostatin. Therefore, this study is to clarify the effect of 4-week hypoxic resistance exercise on Myostatin and Follistatin gene expression in skeletal muscle of rats. Methods Twenty four 8-week-old male SD rats were randomly divided into normoxic control group (group C: 6 rats), normoxic exercise group (group R: 6 rats), hypoxic control group (group H: 6 rats) and hypoxic exercise group (group HR: 6 rats). Rats in each hypoxic group were fed in a hypoxic chamber (atmospheric hypoxia) with oxygen concentration of 12.7% (simulated 4000m altitude). Rats in each exercise group were trained according to the rat's resistance training program developed in our laboratory. After all the intervention, DEXA was used to analyze the body composition. The soleus, extensor digitorum longus and biceps brachii muscles of rats were taken and the wet weight of individual muscles was measured. The data were processed by SPSS17.0 statistical software. The expression level of skeletal muscle mRNA was expressed as "median (25-75%)" and the data of body composition and muscle wet weight were expressed as"mean±standard deviation". The differences between the groups were evaluated using a one-way analysis of variance (ANOVA) test. The significance level for the study was less than 0.05. Results Body composition analysis after 4 weeks of hypoxic intervention showed that the body weight of rats in group H decreased significantly (p=0.012), and the muscle mass decreased more significantly (p<0.001). But resistance exercises obviously reduced the muscle atrophy (p<0.01) caused by hypoxia. After analyzing the changes of the wet weight of individual muscles, it was found that the wet weight of biceps brachii in HR group was significantly higher than that in H group (p=0.048). After 4 weeks of hypoxic intervention and hypoxic resistance exercise, the expression of Myostatin mRNA in individual muscles of each group changed differently. The expression of Myostatin mRNA in soleus muscle of H group was significantly higher than that of C group (371.2%) after 4 weeks of hypoxia intervention. Myostatin mRNA expression in soleus and biceps brachii of HR group was significantly lower than that of H group (591.1% and 478.4% respectively). However, there was no significant difference in the expression level of Myostatin mRNA in the extensor digitorum longus between each group (p=0.259). The change of Follistatin mRNA expression in different groups also showed a different trend. The expression of Follistatin mRNA in soleus muscle and biceps brachii muscle was significantly different among groups (p=0.003, p=0.004, respectively). However, there was no significant difference in the expression level of Follistatin mRNA in the extensor digitorum longus between each group (p=0.734). Myostatin mRNA/Follistatin mRNA ratio (M/F) showed a more significant difference. The M/F ratio of soleus muscle in group H was significantly lower than that in group C (p<0.001), but the M/F ratio in group HR was significantly higher than that in group H (p<0.001). The M/F ratio of biceps brachii in group H was significantly lower than that in group C (p<0.001), but the M/F ratio in group HR showed a higher trend than that in group H (p=0.051). Conclusions Hypoxic exposure results in an increase in Myostatin mRNA expression in skeletal muscle, but hypoxic resistance exercise reduces such an increase. On the contrary, the level of Follistatin mRNA expression in skeletal muscle decreased after hypoxic exposure, and hypoxic resistance exercise could slow down the decline. As a result, rat resistance exercise significantly slowed down hypoxia-induced muscle atrophy. In conclusion, the mutual restriction between Myostatin and Follistatin is one of the main links of resistance exercise to reduce hypoxia-induced skeletal muscle atrophy. However, the process of resistance training to reduce the hypoxia-induced skeletal muscle atrophy is very complex. There are many molecular signaling pathways involved, which need further study.

OR-044 Effect of Elastic Band Exercise, Brisk Walking and the Diabolo Exercise on the Serum Lipid Level of Women with dyslipidemia between 60 to 69 Years Old

Objective This study investigated the effect of elastic band exercise, brisk walking and the diabolo exercise on the serum lipid level of abnormal blood lipids women between 60 to 69 years old. Methods 252 subjects were randomly divided into the elastic band exercise group (EBG), the brisk walking group (BWG), the diabolo exercise group (DEG) and the control group (CG), each group of 63 people. In the end, 186 people (NEBEG=63, NBWG=45, NDEG=32, NCG=46) completed all the tests in 12 weeks due to various reasons, such as withdrawal, travel abroad, and hospitalization. The EBG and the DEG respectively carry on the self-braiding and the Diabolo exercise(DE) training for 1 h, 3 times per week for12 weeks. Participants in the BWG wore pedometers for brisk walking, 5 times per week, and 8,000 to 10,000 steps per time. The CG did not intervene. Measurement on height, body weight, TG, TC, HDL-C, LDL-C were made at two time points—baseline, 12 weeks. Results After 12 weeks of exercise, TG, TC and LDL-C levels of the EBG, BWG and DEG were significantly lower than those in the pre-test group, and the difference was statistically significant, there was no significant change in the control group. The average level of HDL-C in the BWG and DEG was higher than that before the experiment, and the difference was statistically significant. The average level of TG change rate (P50= 0.16) of DEG was greater than EBG (P50=0.09) and BWG(P50=0.05), all of the experimental group were greater than the CG, and the difference was statistically significant. The average level of TC change rate of the EBG, BWG and DEG was greater than the CG, and the difference was statistically significant. The average level of HDL-C change rate in both BWG (P50=0.06) and DEG (P50=0.14) was greater than that of the EBG (P50=0.01) and the CG (P50=0), and the difference was statistically significant. The average level of LDL-C change rate of the EBG(P50=0.06) and the BWG(P50=0.13) was larger than that of the CG (P50= -0.04) and the DEG (P50= -0.08), and the difference was statistically significant. The EBG is compared with the BWG, and the comparison between DEG and CG, the difference was not statistically significant. Conclusions The TG level in the blood was significantly reduced in the EBG, BWG and DEG, and the effect of the diabolo exercise(DE)was better than that of the elastic band exercise (EBE)and the brisk walking(BW). The EBE, BW and DE can significantly reduce the TC level in blood. Both BW and EBE can raise the level of HDL-C in the blood. Both the EBE and BW can reduce the level of LDL-C in the blood。Therefore, all three types of exercise can effectively regulate the Serum Lipid Level of elderly women with dyslipidemia and reduce the risk of ASCVD.

PO-305 An 8-week, low carbohydrate, high fat, ketogenic diet enhanced exercise capacity through improved ketolysis and lipolysis in mice

Objective Carbohydrates, lipids and proteins are utilized both for energy production and structure of body. Among them, protein is the most important component of our body, carbohydrates and lipids are more flexible for energy supply system. Due to carbohydrate pitfall and lipid reserve abundance, coaches and elite athletes aspirate for an effective way to enhance fat utilization. Meanwhile, intramuscular triacylglycerol (IMTG) is a special way for skeletal muscle to store lipids. During exercise, IMTG may contribute up to 20% of total energy turnover, thus contribute significantly for ATP synthesis during exercise. However, abnormal or excessive fat deposition in skeletal muscle may induce insulin resistance as well. Intramuscular lipolysis regulation is crucial for energy supply system during exercise. It is reported by Amati and colleagues that well-trained athletes exhibit higher levels of IMTG and diacylglycerol (DAG) as well as well-preserved sensitivity to insulin, indicating lipolysis ability may be enhanced during exercise. In our previous study, we reported that an 8-week, a low carbohydrate, ketogenic diet increased running time till exhausted in male C57BL6/J mice, presuming the mechanism to be enhanced fat utilization. In the present study, we observed the alternation pattern of messenger RNAs related to lipid mobilization, fatty acid utilization and ketone body oxidation in muscle and adipose tissue immediately after exercise in both Type 1 and Type 2 muscle fibers. Materials and Methods Male C57BL/6J mice (n = 35) were purchased from Takasugi Experimental Animals Supply (Kasukabe, Japan) at 7 weeks of age. All mice were randomly divided into four groups: chow diet (control: Con), including chow diet, sedentary (n = 8) and chow diet plus exercise (Con + Ex, n = 9), ketogenic diet (KD), including KD, sedentary, n = 9, and KD plus exercise (KD + Ex, n = 9) groups. A KD diet TP-201450 (consisting of 76.1% fat, 8.9% protein and 3.5% carbohydrate, 7.342 kcal/g) and a chow diet AIN93G (consisting of 7% fat, 17.8% protein and 64.3% carbohydrate, 3.601 kcal/g) wt/wt were obtained from Trophic (TROPHIC Animal Feed High-tech Co., Ltd., Nantong, Jiangsu, China). Mice were maintained on ad libitum chow diet or KD. Total RNA was extracted from the gastrocnemius muscle, soleus muscle and epididymal adipose tissue using the RNeasy Mini Kit or RNeasy Lipid Mini Kit (Qiagen, Valencia, CA) according to the manufacturer’s instructions. Total RNA was reverse transcribed to cDNA using the High Capacity cDNA Reverse Transcription Kit (Applied Biosystems, Foster City, CA) according to the manufacturer’s instructions. PCR was performed with the Fast 7500 real-time PCR system (Applied Biosystems) using the Fast SYBR® Green PCR Master Mix (Applied Biosystems). Plasma IL-6 was measured using a R&D Mouse ELISA Duo set (R&D Systems, Minneapolis, USA) according to the manufacture’s instructions. Plasma glycerol was measured using Glycerol Colorimetric Assay Kit (Cayman Chemical Co., Ann Arbor, MI, USA). Results and Discussion 3.1 IL-6 concentration and exercise-induced myokine IL-6 mRNA alternation in both muscle fiber IL-6 plays essential roles in immune responses. However, exercise induced IL-6 is reported to be able to stimulate lipolysis both in IMTG pool intramuscularly and adipocytes. Defined as exercise factor, or so-called myokines, muscle-derived IL-6 exhibits regulating function in various experiment circumstances. Recombinant human IL-6 infusion showed an enhanced lipolysis and fat oxidation capacity in human subjects. Genetically IL-6 deficient mice presented a reduced ability on lipolysis and fatty acid oxidation. During KD administration, fat oxidation is no doubt the predominant, if not the only origin of energy, this make us to suspect IL-6 may be altered by acute exercise. As shown in Figure 1, IL-6 mRNA increased rapidly, with a nearly 100-fold change in slow-twitch muscle fiber, and KD helped to this up-regulation. Transcription IL-6 level increased significantly in KD, compared to Con group subject, in soleus muscle, under the context of exhaustive exercise. This makes us to suspect that IL-6 may contribute to enhanced lipolysis and fatty acid mobilization. However, the effect is not observed in fast-twitch muscle. The result indicated that IL-6 mRNA expression exhibited a muscle fiber specification. Slow-twitch muscle fiber contributes more to endurance exercise, as fast-twitch muscle fiber mainly contributes to explosive strength and acceleration. The difference of fiber function leads to a different secretion mode of IL-6. The error bar is high in both exercise group. We observed an interesting phenomenon: the mice who quit at around 200 minutes has the highest IL-6 mRNA expression (gastrocnemius muscle) and plasma IL-6 concentration in both groups. One reason may be that, as the exercise taking on and gradually reach final fatigue, the call for fatty acid decreases with time. As shown in Figure 2, both muscular IL-6 protein and plasma IL-6 were increased by exhaustive exercise. However, plasma IL-6 is significantly lower in the KD plus exercise group, though IL-6 rose nearly 5-fold in control feed group, it only rose to 2.5-fold in the KD group after exercise. For this phenomenon, the best explanation is that the well-adaption of lipid-centered metabolism, including metabolic flexibility and increased IMTG reservoir weakened the need to pull the trigger; this may also be the answer why KD mice had lower weight. 3.2 Fatty acid mobilation related RNA alternation after exhaustive exercise under endogenous ketosis in epididymal adipose tissue Adipose triglyceride lipase (ATGL) is also known as desnutrin in the first place, is a kind of lipase whose substance is patatin-like phospholipase domain-containing protein. Hormone-sensitive lipase (HSL) is also known as cholesteryl ester hydrolase (CEH), is another intracellular neutral lipase. ATGL and HSL cooperated to break apart fatty acids from TG, after which IMTG-origin fatty acid will be directly used for beta-oxidation, or lipid drop-origin fatty acids will be transported though lipoprotein shipping in the form of VLDL from adipose tissue into muscle fibers during exercise. As shown in Figure 3, mRNA expression levels of lipase were significantly enhanced by KD or exercise, indicating the up-regulated lipid mobilization and utilization ability is enhanced by exercise in adipocytes. However, KD plus exercise reversed this increase. One plausible explain for this phenomenon is the lack of plasma IL-6, thus the ability to mobilize fatty acid from adipose tissue is reduced. Adrenergic blocking agents are reported to harm fatty acid mobilization during fasting, and IL-6 is reported to function as adrenergic hormone. Adipocyte-specific HSL deficiency mice present lowered submaximal exercise capacity. Our experiment design, the protocol for treadmill running is similar to a submaximal exercise. Under this circumstance, fat mobilization seems to be critical. Loss of this mobilizing ability, while exercise capacity is yet enhanced, makes us to suspect whether IMTG plays dominant role in this process. 3.3 Ketolytic RNA alternation after exhaustive exercise under conditions of endogenous ketosis in Type 1 and Type 2 muscle fiber Ketolysis is a complete oxidation of ketone bodies. Ketone bodies are utilized by mitochondria of extrahepatic tissues via a series of enzymatic reactions. Ketolysis is regulated by a rate-limiting enzyme 3-oxoacid CoA-transferase 1 (OXCT)-1 and hydroxybutyrate dehydrogenase (HBDH). Thus, we measured the transcriptional alternation of these enzymes in different muscle tissues. In our previous study, plasma ketone body (KB) increased rapidly in the sedentary KD group. However, after exhaustive exercise, blood KB of those KD mice dropped dramatically, while situation of blood KD in the Con mice showed a different figure. These results indicated that 1n 8-week KD administration has improved ketolysis, the ability for subjects to utilize KB. To investigate the mechanism of this enhancement, we assessed key enzymes in ketolysis in both fiber types. As shown in Figure 4, gene expressions of these enzymes also present a fiber-specification. Since fast-twitch muscle fiber plays a second role in endurance exercise, exercise did not alter ketolytic enzymes in the transcriptional level, in gastrocnemius tissue. However, in the slow-twitch muscle fiber, it was changed. HBDH is up-regulated significantly in the case of KD plus exercise. Results here indicated that HBDH plays the key role in the improvement of exercise capacity by an 8-week KD. 3.4 Lipolysis- and fatty acid oxidation related RNA alternation after exhaustive exercise during endogenous ketosis in Type 1 and Type 2muscle fiber After reaching working site, muscle lipoprotein lipase (LPL) hydrolyzes VLDL and harvests fatty acids at last, which will be finally utilized as primary fuel. Carnitine palmitoyl transferase (CPT)-1A, acyl-CoA oxidase (ACO), hydroxyacyl-coenzyme A dehydrogenase (HADH), medium chain acyl-CoA dehydrogenase (MCAD) and malonyl-CoA decarboxylase (MCD) are key regulating enzymes during fatty acid beta-oxidation. And for IMTG, the fatty acid is harvest by intramuscular lipase, ATGL and HSL. In an article published several years ago, the authors called adipose ATGL and HSL, “the mover and shaker of muscle lipolysis”. As shown in Figure 5, both ATGL and HSL mRNA expression are up-regulated by KD, but not by exhaustive exercise. Combined with results in the above part, enhanced mobilization of fatty acid intramuscularly is the main factor, but not the mobilization from adipocyte. LPL mRNA expression in gastrocnemius exhibited the same pattern of lipase mRNA synthesized by adipose tissue. Combined together, the reduced fatty mobilization from adipocyte, partly being the results of higher blood NEFA and TG, accompanied with enhanced fatty acid gain from IMTG pool, need for LPL was reduced. As shown in Figure 6, in fast-twitch muscle fiber, CPT-1a, ACO and HADH mRNA expressions are enhanced by KD during exhaustive exercise. In slow-twitch muscle fiber, feed played as a main factor regulating fatty acid oxidation. CPT1a, MCAD and MCD mRNA expressions are enhanced. In summary, though tissue specific specificity were observed, overall ability of intramuscular fatty acid mobilization and fatty acid oxidation were enhanced by an 8-week KD feeding, thus contributed to exercise capacity. Compared to a glucose-centered metabolic system, a long-term KD feeding leads to establishment of a fatty acid oxidation-centered metabolic system. Metabolic flexibility is used as a term for the ability to adapt to conditional change in metabolic demand, and an 8-week KD helped established lipid-focused metabolic system through keto-adaption, thus increasing the metabolic flexibility. This is not a denial for the conception “glycogen loading” before competitions, while adequate KD meal may help our body to be more flexible during fuel choosing. Moderate training may enhance the ability to utilize ketone bodies as well as fatty acid, or to increase fatty acid mobilization from adipose tissue. Further investigation is urged to be carried out. Conclusions In the present study, we investigated how an 8-week KD remodeled adipose and muscle metabolic adaptation towards ketolysis, lipolysis and fatty acid oxidation under the circumstance of exhaustive exercise. Along with enhanced fatty acid oxidation capacity, KD also enhanced fatty acid mobilization capacity, ketolysis and lipolysis. These results revealed that an 8-week KD administration enhance exercise performance by up-regulated ketolytic and free fatty acid oxidation ability, indicating KD being a promising diet approach in athletes.

OR-012 The Regulation of NF-κB-TNF-α/IDO/5-HT Axis by Aerobic Exercise against Hippocampal Neuroinflammation in CUMS Depressive Mice

Objective To study the effect of aerobic exercise on the anti-chronic stress depression and the key metabolic enzymes indoleamine 2,3 peroxidase (IDO) of tryptophan and kynurenine pathway. Methods Adopt the method of random numbers to make depression modelling for mice with 1 or 2 kinds of stimulating factors for 28 days in view of the 13 kinds of chronic stress stimulation. Collect and analyse motionless time for FST and TST of mice by using the Noldus EthoVision XT9 system. Test the serum factor level of laboratory mice with Cusabio imported IDO, NF-ƙB and TNF-α kit. Make real-time fluorescent quantitative PCR verification of the mRNA expression and protein expression level of IDO, 5-HT, NF-ƙB and TNF-α in hippocampus. Results After 4 weeks of chronic stress stimulation, the motionless time for FST and TST of mice in the Model Group obviously prolonged (p<0.05). The bioactivity of IDO, NF-ƙB and TNF-α in hippocampus increased. The mRNA expression of IDO, NF-ƙB and TNF-α in hippocampus increased, while the mRNA expression of 5-HT decreased (p<0.01). Aerobic exercise can shorten the motionless time of mice, inhibit the activity of IDO, NF-ƙB and TNF-α, reduce the mRNA expression quantity of IDO, NF-ƙB and TNF-α and enhance the expression of 5-HT. Conclusions Aerobic exercise has an antidepressant effect on mice for chronic stress depression, which is related to the IDO activation induced by inhibit inflammatory cytokines. Aerobic exercise may inhibit the NF-ƙB to reduce the pathway of tryptophan and kynurenine, affect the direct and indirect induced effect of IDO, and adjust its activity and expression.

PO-298 Effect of exercise and Siyeshen upon hippocampal cytochrome c and caspase-3 of diabetic rats

Objective To observe the effects of aerobic exercise and Siyeshen water extract on cytochrome c (Cyt c) and caspase-3 in hippocampus of diabetic rats and to explore the possible mechanism of improving diabetes. Methods Healthy male Wister rats fed with high fat and high sugar and combined with streptozotocin to establish type II diabetes model. They were randomly divided into 4 groups: diabetic control group, exercise group, Siyeshen group and exercise+Siyeshen group, and another normal control group, with 6 rats in each group. After aerobic exercise (15m/min, 5°slope, 60min, every other day) or/and Siyeshen (200mg/kg) gastrointestinal administration for 8w, the expression of Cyt c and caspase-3 in hippocampus of each group were detected by immunoblotting, and mRNA expressions were detected by RT-PCR. Results Compared with the normal control group, the mRNA and protein expressions of Cyt c and caspase-3 in the hippocampus of the diabetic control group were significantly increased (P<0.05). Compared with the diabetic control group, the blood glucose level of exercise group and exercise+ Siyeshen group decreased (P<0.05), the mRNA and protein expression of Cyt c and caspase-3 decreased significantly (P<0.05), but there were no significant changes in the mRNA and protein expression of Cyt c and caspase-3 between Siyeshen group and diabetic control group (P﹥0.05). Conclusions Exercise and exercise combined with Siyeshen can inhibit cytochrome c release and reduce caspase-3 protein expression, which may be related to the improvement of blood glucose levels in diabetic rats.