Electroacupuncture improving obesity-induced insulin resistance via regulating intestinal SIRT1/TLR4 signaling pathway. / ç”µé’ˆè°ƒæŽ§å°è‚ æ²‰é»˜ä¿¡æ¯è°ƒèŠ‚å› å­1/Tollæ ·å—ä½“4ç‚Žæ€§é€šè·¯æ”¹å–„è‚¥èƒ–å¤§é¼ èƒ°å²›ç´ æŠµæŠ—çš„æœºåˆ¶ç ”ç©¶.

OBJECTIVES: To observe the effect of electroacupuncture (EA) in obese rats with insulin resistance (IR) through regulating intestinal silent information regulator 1 (SIRT1)/Toll-like receptor 4 (TLR4) signaling pathway, so as to explore the underlying mechanism of EA in improving obesity-induced IR. METHODS: A total of 40 Wistar rats were randomly divided into 4 groups, i.e. normal group, model group, EA group and EA combined with inhibitor group, with 10 rats in each group. The obesity-induced IR model was induced by feeding high-fat diet for 8 weeks. EA (2 Hz, 1mA) was applied at "Zhongwan"(CV12), "Guanyuan"(CV4), "Zusanli"(ST36) and "Fenglong" (ST40) for 10 min, 3 times a week for 8 weeks in both EA and EA combined with inhibitor groups. Sirtinol, an inhibitor of SIRT1 was injected into the tail vein (1 mg/kg), 3 times a week for 8 weeks in EA combined with inhibitor group. The body weight, glucose infusion rate (GIR) of rats in each group were recorded. The contents of serum C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and lipopolysaccharide (LPS) were detected by ELISA. Mucosal morphological changes in the small intestine was observed by HE staining and was graded using Chiu's score. The protein relative expression levels of SIRT1 and TLR4 and the co-labeling of SIRT1 with TLR4 in the small intestine was detected by Western blot and double immunofluorescence staining, separately. RESULTS: Compared with the normal group, the body weight, serum contents of CRP, TNF-α, IL-6, LPS, Chiu's score, TLR4 protein relative expression level and percentage of TLR4 positive expression area were increased (P<0.01, P<0.05), while the GIR, SIRT1 protein expression, percentage of SIRT1 positive expression area and SIRT1/TLR4 were decreased (P<0.01) in the model group. The pathological injury of small intestine mucosa was severe, accompanied with inflammatory cell infiltration in the model group. Following interventions, the body weight, serum contents of CRP, TNF-α and LPS, Chiu's score, TLR4 protein relative expression level and percentage of TLR4 positive expression area were decreased(P<0.01, P<0.05), and the GIR was increased (P<0.01), the pathological injury and inflammatory cell infiltration of small intestine mucosa were reduced in both EA and EA combined with inhibitor groups in contrast to the model group. Compared with the model group, the serum IL-6 content was significantly decreased (P<0.01), and the SIRT1 protein relative expression level and percentage of positive expression area, SIRT1/TLR4 were increased (P<0.01, P<0.05) in the EA group. Compared with the EA group, EA combined with inhibitor group showed the body weight, serum CRP, IL-6, LPS, Chiu's score, TLR4 protein relative expression level and TLR4 positive expression area were increased (P<0.01, P<0.05), and the GIR level , SIRT1 relative expression level, SIRT1/TLR4 ratio were decreased (P<0.05, P<0.01). CONCLUSIONS: EA can reduce the body weight and ameliorate peripheral insulin sensitivity in IR obese rats, which may be related with its function in regulating intestinal SIRT1/TLR4 signaling pathway to reduce inflammatory response.

Mechanisms of gut microbiota-immune-host interaction on glucose regulation in type 2 diabetes.

Intestinal absorption of food is one of the sources of glucose. Insulin resistance and impaired glucose tolerance caused by lifestyle and diet are the precursors of type 2 diabetes. Patients with type 2 diabetes have trouble controlling their blood sugar levels. For long-term health, strict glycemic management is necessary. Although it is thought to be well correlated with metabolic diseases like obesity, insulin resistance, and diabetes, its molecular mechanism is still not completely understood. Disturbed microbiota triggers the gut immune response to reshape the gut homeostasis. This interaction not only maintains the dynamic changes of intestinal flora, but also preserves the integrity of the intestinal barrier. Meanwhile, the microbiota establishes a systemic multiorgan dialog on the gut-brain and gut-liver axes, intestinal absorption of a high-fat diet affects the host's feeding preference and systemic metabolism. Intervention in the gut microbiota can combat the decreased glucose tolerance and insulin sensitivity linked to metabolic diseases both centrally and peripherally. Moreover, the pharmacokinetics of oral hypoglycemic medications are also influenced by gut microbiota. The accumulation of drugs in the gut microbiota not only affects the drug efficacy, but also changes the composition and function of them, thus may help to explain individual therapeutic variances in pharmacological efficacy. Regulating gut microbiota through healthy dietary patterns or supplementing pro/prebiotics can provide guidance for lifestyle interventions in people with poor glycemic control. Traditional Chinese medicine can also be used as complementary medicine to effectively regulate intestinal homeostasis. Intestinal microbiota is becoming a new target against metabolic diseases, so more evidence is needed to elucidate the intricate microbiota-immune-host relationship, and explore the therapeutic potential of targeting intestinal microbiota.

[Mechanisms of electroacupuncture in improving obesity-induced insulin resistance via TLR4/NF-κB inflammatory pathway in liver].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on the Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) inflammatory pathway in the liver of obese rats with insulin resistance, and explore its mechanism. METHODS: Male Wistar rats were randomly divided into a normal group (n=15) and an experimental group (n=30). The obesity-induced insulin resistance model was induced by the high-fat diet (HFD) in rats of the experimental group for 8 weeks. Subsequently, the model rats were further divided into a model group (n=15) and an EA group (n=15). EA was applied at "Zhongwan "(CV12), "Guanyuan" (CV4), "Zusanli "(ST36) and "Fenglong "(ST40) in the EA group for 10 min, three times a week for 8 weeks. The body weight of rats in each group was measured before intervention and at the 2nd, 4th, 6th, and 8th weeks during the intervention. Glucose infusion rate (GIR) was measured by glucose clamp test before and after treatment. After treatment, fast blood glucose (FBG) was detected by the glucometer, and homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. The contents of fasting insulin (FINS), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) were determined by ELISA. The protein expressions of TLR4, IκB kinase ß (IKKß), phosphorylated IKKß (p-IKKß), NF-κB p65, and TNF-α related to the TLR4/NF-κB signaling pathway in the liver of rats were detected by Western blot. RESULTS: Compared with the normal group, the body weight, HOMA-IR levels, serum levels of FINS, TNF-α, and IL-6 were up-regulated (P<0.01), and the GIR level was down-regulated (P<0.01), the protein expressions of TLR4, IKKß, p-IKKß, NF-κB p65 and TNF-α in liver tissues were increased(P<0.05) in the model group. Compared with the model group, the EA group showed weight loss from the 6th week, and the HOMA-IR levels，serum levels of FINS, TNF-α, and IL-6 were decreased(P<0.01, P<0.05), the GIR level was up-regulated (P<0.01), the protein expressions of TLR4, IKKß, p-IKKß, NF-κB p65 and TNF-α in liver tissues were down-regulated (P<0.05). CONCLUSION: EA can reduce the inflammatory response and improve peripheral insulin sensitivity by inhibiting the TLR4/NF-κB pathway in liver tissues of obese rats with insulin resistance, showing a good regulatory effect on insulin resistance induced by obesity.

[Effect of electroacupuncture at different acupoint combination on intestinal inflammatory response and intestinal flora in obese rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) at different acupoint combination on intestinal inflammatory response, intestinal flora structure and metabolic function in obese rats. METHODS: Ninety male Wistar rats aged 8 weeks were collected. Ten rats were randomly collected from 15 rats fed with regular forage in a normal group and the rest 75 rats were fed with high-fat forage to induce obesity models. Forty rats were modeled successfully and randomized into a model group, a lower-limb EA group, an abdomen EA group and a biaoben acupoints group, 10 rats in each one. "Zusanli" (ST 36) and "Fenglong" (ST 40) were selected in the lower-limb EA group, "Zhongwan "(CV 12), "Tianshu "(ST 25) and "Guanyuan" (CV 4) were selected in the abdomen EA group. The acupoint prescriptions in the above two groups were combined in the biaoben acupoints group. EA was delivered in all of the intervention groups, with continuous wave, 2 Hz in frequency and 1 mA in current intensity. The intervention was administered three times weekly (on Monday, Wednesday and Friday), for consecutive 8 weeks. Before intervention and on the last day of the 8th week of intervention, the body weight and 24 h food intake were observed. After intervention, using Western blot method, the proteins expressions of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were detected in the tissue of the small intestine; 16S rRNA sequencing technology was adopted to detect the distribution structure and metabolic function of intestinal flora. RESULTS: Compared with the normal group, the body weight, the food intake and the proteins expressions of IL-6 and TNF-α in small intestine were all increased in the model group (P<0.01). The above indexes of each EA intervention group were all decreased (P<0.01) when compared with the model group. The proteins expressions of IL-6 and TNF-α in the small intestine tissue of rats in biaoben acupoints group were lower than those in the other two EA intervention groups (P<0.01). Compared with the normal group, the ratio of Firmicutes/Bacteroidetes was elevated (P<0.01), while the abundance of Lactobacillus, Muribaculaceae and Bifidobacteria decreased in the model group (P<0.01). When compared with the model group, the ratio of Firmicutes/Bacteroidetes in each EA intervention group was reduced (P<0.01) and the abundance of Lactobacillus, Bifidobacteria and Bacteroidetes increased (P<0.01). Compared with the other two EA intervention groups, the abundance of Lactobacillus and Muribaculaceae was increased (P<0.01), while the abundance of Collinsella and Ruminococcus Gauvreauii reduced (P<0.01) in the biaoben acupoints group. In the model group, the abundance of clusters of orthologous groups of proteins (COG) function of intestinal flora in the transportation and metabolism of carbohydrate, amino acid and lipid, as well as in the signal transduction mechanisms were reduced when compared with the normal group (P<0.01). In comparison with the model group, the abundance of the above COG function was increased in each EA intervention group (P<0.01, P<0.05). CONCLUSION: Electroacupuncture at biaoben acupoint combination may attenuate intestinal inflammatory response and effectively improve the structure and function of intestinal flora. The effect is superior to the intervention at the acupoints on the lower limbs and those on the abdomen, better regulating the abundance of specific intestinal flora.

[Effect of electroacupuncture stimulation of different acupoint groups on lipid metabolism and liver TLR4/NF-κB signaling in obese rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of different acupoint combinations on lipid metabolism and liver Toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κB) signaling in obese rats, so as to explore the specificity of regulatory effects of different acupoints for obesity. METHODS: Male SD rats were randomly divided into normal control, model, hindlimb acupoint EA ï¼»"Fenglong" (ST40)-"Zusanli" (ST36), hindlimb EAï¼½, abdominal acupoint EA ï¼»("Zhongwan" (CV12)-"Tianshu" (ST25), "Guanyuan" (CV4) - the opposite ST25, abdominal EAï¼½, BiaoBen-acupoint EA ï¼»ST40-ST36, CV12 -CV4, ST25, BiaoBen EAï¼½ groups, with 10 rats in each group. The obesity model was induced by feeding the rats with high fat diet. EA (2 Hz, 1 mA) was applied to the acupoint groups mentioned above for 10 min (per acupoint group), 3 times a week for 8 weeks. After the treatment, the body weight and food intake in each group were recorded. The contents of serum total cholesterol (TC), triglyceride (TG), non-esterified fatty acid (NEFA) were detected by using an automatic biochemical analyzer. The expression levels of TLR4 and NF-κB p65 mRNAs and proteins in the liver tissue were detected by quantitative real-time PCR and Western blot, separately. RESULTS: Compared with the normal group, the body weight and food intake, serum TC, TG and NEFA contents, hepatic TLR4 and NF-κB p65 protein and gene expression were significantly increased in the model group (P<0.05, P<0.01). After the treatment, compared with the model group, the body weight, food intake, TC, TG, NEFA, TLR4 and NF-κB p65 protein and mRNA expression were significantly decreased in the hindlimb EA, abdominal EA and BiaoBen EA groups (P<0.05, P<0.01). Comparison among the 3 treatment groups showed that the serum TC, TG and NEFA contents were significantly lower in the hindlimb EA and BiaoBen EA groups than in the abdominal EA group (P<0.01，P<0.05). The expression levels of TLR4 and NF-κB p65 mRNAs and proteins were significantly lower in the BiaoBen EA group than in the hindlimb EA and abdominal EA groups (P<0.01, P<0.05). CONCLUSION: BiaoBen EA is superior to abdominal EA in improving lipid metabolism in obesity rats, which may be related to its stronger effectiveness in down-regulating hepatic TLR4/NF-κB p65 signaling.

[Mechanism of electroacupuncture for regulation of lipid production and improvement in obesity by mediating Wnt/ ß-catenin pathway through activating SIRT1].

OBJECTIVE: To explore the mechanism of electroacupuncture (EA) for the regulation of lipid production and improvement in obesity by mediating Wnt/ß-catenin pathway through activating silent information regulator 1 (SIRT1). METHODS: Of 75 Wistar male rats, 10 rats were selected randomly as the normal group and fed with standard diet. The rest rats were fed with high-fat diet for 8 weeks to establish the obesity model. Forty rats of successful modeling were randomized into a model group, an EA group, an EA plus inhibitor group (EA+I group) and an agonist group, 10 rats in each one. In the EA group, EA was applied at "Guanyuan" (CV 4), "Zhongwan" (CV 12), "Zusanli" (ST 36) and "Fenglong" (ST 40), with continuous wave, 2 Hz in frequency and around 1 mA in intensity. The needles were retained for 20 min. In the EA+I group, sirtinol solution was injected from caudal vein and EA was exerted simultaneously. In the agonist group, resveratrol solution was given by intragastric administration. The intervention of the above three groups was given once every two days, 3 times a week, consecutively for 8 weeks. Before and after intervention, body mass and Lee's index were recorded in the rats of each group. After intervention, the levels of serum total cholesterol (TC), triglyceride (TG) and free fatty acid (FFA) were detected in the rats of each group. After intervention, the mass of white adipose tissue (WAT) and the area of adipocytes were compared in the rats among the 5 groups. Using Western blot method, the protein expressions of SIRT1, glycogen synthase kinase-3ß (GSK3ß), ß-catenin, cyclin D1 and peroxisome proliferators-activated receptor γ (PPARγ) were detected in WAT in the rats of each group. RESULTS: After intervention, compared with the model group, the body mass and Lee's index were reduced in the rats of the EA group and the agonist group (P<0.01, P<0.05), the body mass was reduced in the rats of the EA+I group (P<0.05). Compared with the normal group, the levels of serum TC, TG and FFA, as well as WAT mass were increased in the rats of the model group (P<0.01), as well as the area of adipocytes (P<0.01). Compared with the model group, the levels of serum TC and TG (except in the EA+I group), the levels of FFA and WAT mass were all decreased (P<0.01, P<0.05) and the area of adipocytes was reduced (P<0.01, P<0.05) in the EA group, the agonist group and the EA+I group. Compared with the EA group, the area of adipocytes was increased in the EA+I group (P<0.05). Compared with the normal group, the protein expressions of SIRT1, ß-catenin and cyclin D1 in WAT were down-regulated (P<0.01) and the protein expressions of GSK3ß and PPARγ in WAT were up-regulated (P<0.01) in the model group. Compared with the model group, the protein expressions of SIRT1, ß-catenin and cyclin D1 in WAT were up-regulated (P<0.05, P<0.01) and the expressions of GSK3ß and PPARγ in WAT were down-regulated (P<0.01, P<0.05) in the EA group and the agonist group, and in the EA+I group, GSK3ß protein expression was down-regulated andß-catenin protein expression was up-regulated (P<0.05). CONCLUSION: Electroacupuncture remarkably improves the body mass, Lee's index and blood lipid metabolism and reduces WAT mass and adipocyte size in obesity model rats, which is probably related to up-regulating the protein expression of SIRT1 in WAT, activating Wnt/ß-catenin pathway and inhibiting the expression of PPARγ of downstream lipogenic gene so as to affect lipid production.

[Electroacupuncture improves obesity by lowering gastrointestinal motility, blood lipids and expression of intestinal leptin and cholecystokinin in obese rats].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on gastrointestinal motility and expression of leptin(LEP) and cholecystokinin(CCK) in the small intestine in obese rats，so as to explore the mechanism of EA underlying improvement of obesity. METHODS: Male Wistar rats were randomized into 5 groups: normal control, obesity model, abdominal acupoints ［"Guanyuan" (CV4), "Zhongwan" (CV12) and bilateral "Tianshu" (ST25)］, lower-leg acupoints ［bilateral "Zusanli" (ST36) and bilateral "Fenglong" (ST40)］, and abdominal+ lower-leg acupoints (n=10 rats in each group). The obesity model was established by feeding the animals with high-fat diet for 8 weeks. EA was applied to the abovementioned acupoints for 20 min every time, 3 times a week for 8 weeks. The food intake and body mass were recorded. The white adipose tissue around the testicles and in the abdominal region was weighed. The serum total cholesterol (TC), triglyceride (TG) and non-esterified fatty acid(NEFA) were detected by using automatic biochemical analyzer. The gastric empty rate and intestinal propulsive rate were calculated. The contents of serum CCK and LEP were detected by using ELISA, and the expression levels of CCK and LEP proteins in the small intestine were detected by using Western blot. RESULTS: Following modeling, the food intake, body mass, weight of white adipose around the testicles and abdomen, the gastric empty rate, and serum TC, TG, NEFA and LEP contents as well as intestinal LEP expression were significantly increased (P<0.05, P<0.01), while the intestinal propulsive rate, serum CCK content and intestinal CCK expression were evidently decreased (P<0.01) in the model group relevant to the normal control group. After EA interventions and compared with the model group, the increased levels of food intake, body mass, white adipose weight, gastric empty rate, TC, TG, and LEP in serum and small intestine, and the decreased levels of intestinal propulsive rate, CCK in the serum and intestine were reversed in the abdominal acupoints, lower-leg acupoints and abdominal+lower-leg acupoints groups (P<0.05, P<0.01). No significant differences were found in the effects of the three EA groups in down-regulating food intake, body mass, white adipose weight, gastric empty rate, serum TC, TG and LEP levels (except NEFA) and in up-regulating intestinal propulsive rate and CCK level (P>0.05). CONCLUSION: EA stimulation of the abdominal and lower-leg acupoints or both can reduce body weight on obesity rats, which is associated with its functions in regulating intestinal motility, food intake, and secretion of LEP and CCK.

[Prospects and Progress on the Mechanisms of Acupuncture Underlying Improvement in Diabetic Gastroparesis].

Diabetic gastroparesis (DGP) is an important complication of diabetes, and seriously impacts the patient's quality of life. In the present paper, the authors summarize national and international research on the mechanism of acupuncture therapy in improving DGP and the pathogenesis of DGP over the past 10 years. The authors illustrate the mechanism of acupuncture underlying the improvement in DGP as follows:1) the effect on autonomic nerves and neurons of the central nervous system; 2) promoting restoration of the enteric nervous system; 3) the effect on Cajal interstitial cells; 4) improving gastrointestinal hormone disorder; 5) improving hyperglycemic state; 6) the effect on gastric smooth muscle. The authors also put forward some suggestions for future research on the mechanisms of acupuncture in DGP.