Alpinia officinarum Hance extract ameliorates diabetic gastroparesis by regulating SCF/c-kit signaling pathway and rebalancing gut microbiota.

Diabetic gastroparesis (DGP) is a common complication of type 2 diabetes mellitus (T2DM). Alpinia officinarum Hance (AOH) is one of the most commonly used both as a food and folk medicines, which is rich in diarylheptanoids and flavonoids. The gastroprotection and hypoglycemic effect make AOH has great potential in developing of anti-DGP complementary medicine. However, the molecular mechanisms of AOH that act against DGP are yet to be elucidated. In this study, we evaluated the therapeutic effects, the potential molecular mechanism, and the changes of gut microbiota of AOH in DGP. The 5 components of the AOH were analyzed, and the potential signaling pathway of AOH improving DGP was predicted by molecular docking. Subsequently, DGP rat model was constructed using high-fat-irregular-diet, AOH intervention significantly reduced blood glucose levels, increased gastrointestinal propulsion rate, and improved gastric histological morphology in DGP rats. Meanwhile, AOH has been shown to regulate the SCF/c-kit signaling pathway and rebalance the gut microbiota, which may be closely related to its role in improving DGP. Taken together, AOH may play a protective role on DGP through multiple mechanisms, which might pave the road for development and utilization of AOH.

[Electroacupuncture promotes gastrointestinal motility by activating autophagy of Cajal interstitial cells via downregulating PI3K/Akt/mTOR signaling pathway in stomach of diabetic gastro-paresis rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Zusanli" (ST36), "Sanyinjiao" (SP6) and "Liangmen" (ST21) on gastrointestinal motility, blood glucose content and expression of autophagy-related proteins 1 light chain 3 (LC3), p62, phosphatidyli-nositol-3 kinase (PI3K), protein kinase B (Akt), p-Akt and mammalian target protein of rapamycin (mTOR) of interstitial cells of Cajal (ICCs) in the cultured gastric antrum cells in diabetic gastroparesis (DGP) rats, so as to reveal its mechanisms underlying improvement of DGP. METHODS: A total of 45 Sprague Dawley (SD) rats were randomly divided into blank control, model, EA, medication (3-methyladenine, 3-MA) and EA+3-MA groups, with 9 rats in each group. The DGP model was established by intraperitoneal injection of 2% streptozotocin (STZ) combined with high-fat and high sugar diet for 8 weeks. The gastric emptying rate was measured by using gavage of phenol red (to measure the propelling length of the phenol red/total length of small intestine ×100%). The symptom score (mental state, coat color and luster, behavior and activity, stool traits) of rats was observed every week and the blood glucose content was measured by using a glucometer. EA (20 Hz/100 Hz, 2 mA) was applied to unilateral ST36, SP6 and ST21 alternatively for 15 min, once daily, 5 days a week for 3 weeks. Rats of the 3-MA and 3-MA+EA groups received intraperitoneal injection of 3-MA (30 mg·kg-1·d-1, 10 mg/mL), once daily, 5 days a week for 3 weeks. After 15 days' intervention, the rats were operated for gastric emptying rate test, specimen collection, isolation, and culture of primary ICCs. The expression levels of microtubule associated protein LC3, p62, PI3K, Akt, p-Akt and mTOR of ICCs of cultured gastric antrum cells were detected using Western blot, and the number of autophagosomes in ICC of gastric antrum was observed under transmission electron microscope. RESULTS: Compared with the blank control group, the symptom score, blood glucose, and the expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins were increased significantly (P<0.01), while the gastric emptying rate and ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein were significantly decreased (P<0.05, P<0.01) in the model group. In comparison with the model group, the increase of symptom score, blood glucose, and expression levels of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins and the decrease of gastric empty rate and LC3Ⅱ/LC3Ⅰ ratio and the expression level of class Ⅲ PI3K protein were all reversed in both EA and EA+3-MA groups (P<0.05, P<0.01), rather than in the 3-MA group. In addition, 3-MA also reversed modeling-induced increase of class Ⅰ PI3K, Akt, p-Akt and mTOR proteins expression (P<0.01). No significant differences were found between the EA and EA+3-MA in downregulating the levels of symptom score and blood glucose content, and in upregulating gastric empty rate(P>0.05). The effect of EA was notably superior to that of EA+3-MA in upregulating the ratio of LC3Ⅱ/LC3Ⅰ and the expression level of class Ⅲ PI3K protein, and in downregulating the expression of p62, class Ⅰ PI3K, Akt, p-Akt and mTOR proteins (P<0.05, P<0.01). The findings of transmission electron microscopy showed obvious swelling, breakage of some mitochondrial cristae in the ICC cells of antrum and no autophagosomes in the model group and 3-MA group, which was milder in the damage of mitochondrial cristae and marked increase in the autophagosomes in both EA and EA+3-MA groups. CONCLUSION: EA can improve the gastrointestinal motility and symptoms in DGP rats, which may be related to its functions in downregulating PI3K/Akt/mTOR signaling to promote autophagy level of ICC.

[Effect of electroacupuncture combined with Zhuang-medicine-thread moxibustion on expression of apoptosis-related factors in gastric antrum of diabetic gastroparesis rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with Zhuang-medicine-thread moxibustion on expression of apoptosis-related factors in gastric antrum of diabetic gastroparesis (DGP) rats, so as to explore its mechanism underlying improvement of DGP. METHODS: Male SD rats were randomly divided into normal, model, medication, EA, Zhuang-medicine-thread moxibustion (moxibustion) and EA+moxibustion (combination) groups (12 rats in each group). The DGP model was established by intraperitoneal injection of streptozotocin (STZ). Rats of the medication group were treated by gavage of 0.15 mg/mL mosapride citrate suspension （10 mL/kg）. EA (10 Hz/50 Hz, 2 mA, 20 min) or Zhuang-medicine-thread moxibustion (3 cones) was applied to "Zhongwan" (CV12), bilateral "Neiguan" (PC6) and bilateral "Sanyinjiao" (SP6) of the related groups, once a day for 3 weeks. The blood glucose, gastric emptying rate and intestinal propulsion rate of rats were measured. The apoptosis index of gastric antrum cells were observed by TUNEL staining. The protein and mRNA expressions of Caspase-3, B-cell lymphoma/leukemia-2 (Bcl-2) and Bcl-2 associated X protein (Bax) in gastric antrum were detected by Wes-tern blot and real-time quantitative PCR, respectively. RESULTS: Compared with the normal group, the blood glucose, the apoptosis index, the protein and gene expressions of Caspase-3 and Bax were significantly increased (P<0.01), and the gastric emptying rate, intestinal propulsive rate, the protein and gene expressions of Bcl-2 were considerably decreased (P<0.01) in the model group. In contrast to the model group, the blood glucose in the EA, moxibustion and combination groups, the apoptosis index in the 4 treatment groups, as well as Caspase-3 protein, Bax protein and mRNA expressions in the medication, EA and combination groups, Caspase-3 protein and mRNA, Bax mRNA expressions in the moxibustion group were significantly decreased (P<0.01, P<0.05); while the gastric emptying rate and intestinal propulsive rate in the 4 treatment groups, and Bcl-2 protein and mRNA expressions in the medication and combination groups, Bcl-2 mRNA expressions in the EA and moxibustion groups were obviously increased (P<0.01). The effects of EA+moxibustion were significantly superior to those of simple EA, moxibustion or medication in increasing gastric emptying rate and intestinal propulsive rate, and in lowering blood glucose (P<0.05, P<0.01). And the effects of the combination treatment were better than those of EA in lowering Caspase-3 protein and Bax mRNA expressions (P<0.01), and in increasing Bcl-2 protein and mRNA expressions (P<0.05, P<0.01). Also the effects of the combination treatment were better than those of moxibustion in lowering the apoptosis index, Caspase-3 protein, and Bax protein and mRNA expressions (P<0.01, P<0.05), and in increasing Bcl-2 protein expression (P<0.05). CONCLUSION: EA combined with Zhuang-medicine-thread moxibustion can reduce blood glucose and improve gastrointestinal motility in DGP rats, which may be related to its effect in regulating of Caspase-3, Bax and Bcl-2 expression.

[Effect of Point-moxibustion and Electroacupuncture on the Expression of Endothelial Nitric Oxide Synthase mRNA and Angiotensin 2 mRNA in Gastric Antrum in Diabetic Gastroparesis Rats].

OBJECTIVE: To observe the effect of point-moxibustion and electroacupuncture(EA) on gastrointestinal motility, and expression of endothelial nitric oxide synthase(eNOS) mRNA and angiotensin 2(AT Ⅱ) mRNA in gastric antrum in diabetic gastroparesis(DGP) rats, so as to reveal the different effect between point-moxibustion and EA, and explore the mechanism underlying improvement of DGP. METHODS: Forty SD rats were randomly divided into normal, model, point-moxibustion and EA groups, 10 rats in each group. The DGP model was established by intraperitoneal injection of streptozotocin (STZ, 2%, 55 mmol/kg) and fed with high-sugar and high-fat fodder. "Zusanli" (ST 36), "Sanyinjiao" (SP 6) and "Liangmen" (ST 21) were chosen to be stimulated with moxibustion at 0, 10 and 20 min in the point-moxibustion group or with EA for 20 min in the EA group. The treatment was conducted once daily for 15 days. After treatment, blood glucose, gastric emptying rate and small intestinal propulsive rate were measured. The plasma endothelin 1(ET-1) content was detected by ELISA. The mRNA expression of eNOS and AT Ⅱ in gastric antrum were detected by Real-time PCR. RESULTS: Compared with the normal group, the blood glucose in the model group was significantly higher (P<0.01). Compared with the model group, the blood glucose decreased significantly in the point-moxibustion group and EA group (P<0.05). In comparison with the normal group, gastric emptying rate and small intestinal propulsive rate were decreased, the content of plasma ET-1 was increased, the expression of eNOS mRNA in gastric antrum was significantly reduced and the expression of ATⅡ mRNA was significantly increased in the model group(P<0.01). In comparison with the model group, gastric emptying rate and small intestinal propulsive rate were increased, the content of plasma ET-1 was decreased, the expression of eNOS mRNA in gastric antrum was higher and the expression of AT Ⅱ mRNA was significantly lower in both point-moxibustion group and EA group (P<0.05), and there were no significant differences between the two treatment groups in above mentioned indexes (P>0.05). CONCLUSIONS: Both point-moxibustion and EA can effectively promote gastrointestinal motility in DGP rats and improve the symptoms of delayed gastric emptying. The two therapies are effective, and their mechanism may be related to the increase of eNOS mRNA expression and the decrease of AT Ⅱ mRNA expression in gastric antrum.

[Effect of Electroacupuncture at "Zusanli" (ST 36), etc. on Gastrointestinal Motility and Expression of Ghrelin mRNA and Growth Hormone Secretagogue Receptor mRNA in Diabetic Gastroparesis Rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) stimulation of "Zusanli" (ST 36), "Liangmen" (ST 21) and "Sanyinjiao" (SP 6) on gastrointestinal motility and expression of ghrelin and growth hormone secretagogue receptor (GHSR) mRNA in diabetic gastroparesis (diabetic gastroparesis, DGP) rats, so as to explore its mechanism underlying improvement of diabetic gastroparesis. METHODS: Sixty SD rats were randomly and equally divided into normal control, model, EA acupoint, EA non-acupoint, medication (metoclopramide) groups (n = 12 rat/group). The DGP model was established by intraperitoneal injection of streptozotocin (STZ, 55 mg/kg, 2%) and raised by high-sugar and high-fat fodder irregularly for 8 weeks. EA was applied to "Zusanli" (ST 36), "Liangmen" (ST 21) and "Sanyinjiao" (SP 6), and non-acupoints (about 5 mm lateral to the 3 acupoints, respectively). Those rats of the medication group were given with metoclopramide (1 mL/100 g). The blood sugar level was measured by glucometer, and the urine sugar level measured by Tes-Tape [urine glucose test paper]. The intestinal propulsion rate (IPR) was identified as ratio of the phenolsulfonphthalein promoting distance and the total length of the small intestine, and the gastric emptying rate (GER) was assessed by gavage of a liquid test meal (1.5 mL) containing a nonabsorbable marker (0. 5 mg/mL of phenol red in 5% glucose solution) and identification after being sacrificed 72 h after modeling. The expression levels of ghrelin mRNA and GHSR mRNA of gastric antrum tissue were examined by Quantitative real-time PCR. RESULTS: In comparison with the normal control group, the blood sugar and urine sugar levels of the model group was significantly increased in the model group (P < 0.01), while the GER and IPR and the expression level of ghrelin mRNA and GHSR mRNA in the gastric antrum were significantly decreased in the model group (P < 0.01, P < 0.05). Following EA stimulation of acupoint, the blood sugar and urine sugar levels were obviously down-regulated (P < 0.05), both GER and IPR, and ghrelin mRNA and GHSR mRNA expression levels in the EA-acupoint group were significantly up-regulated (P < 0.05, P < 0.01). No significant changes were found in both blood sugar and urine sugar levels, in both GER and IPR, and ghrelin mRNA and GHSR mRNA expression levels of both EA non-acupoint and medication groups after the intervention (P > 0.05). The GER and IPR were significantly higher in the EA acupoint group than in the EA non-acupoint group (P < 0.05, P < 0.01). CONCLUSION: EA stimulation of ST 36, ST 21 and SP 6 can promote the gastrointestinal motility of DGP rats, which may be closely associated with its effects in up-regulating the expression level of ghrelin mRNA and GHSR mRNA in gastric antrum.

[Effect of moxibustion with ignited Zhuang-medicine medicated-thread on interstitial cells of Cajal in gastric antrum in diabetic gastroparesis rats].

OBJECTIVE: To observe the effect of Zhuang-medicine medicated-thread moxibustion therapy on interstitial cells of Cajal (ICC) in the gastric antrum of diabetic gastroparesis (DGP) rats, so as to investigate its mechanism underlying improving DGP. METHODS: Sprague-Dawley (SD) male rats were randomly divided into 3 groups: control (n = 30) , model (n = 30) and moxibustion (n = 30). The DGP model was established by intraperitoneal injection of streptozotocin (STZ) and by feeding the rats with high fat-sugar forage. Zhuang-medicine medicated-thread moxibustion was applied to "Zhongwan" (CV 12), bilateral "Pishu" (BL 20), "Weishu" (BL 21), "Neiguan" (PC 6) and "Zusanli" (ST 36) once per day, for 3 weeks except weekends. The gastrointestinal propulsion rate and weight of stool in 24 h were determined, and c-kit (a marker for ICC) expression of the gastric antrum tissue was measured by immunohistochemistry. RESULTS: The stool weight was significantly higher in the model group than in the control group (P < 0.01), but the rate of gastrointestinal propulsion and the rate of c-kit immunoreaction (IR) positive cells in the gastric antrum tissue were significantly lower in the model group than in the control group (P < 0.01). After moxibustion, the increased stool weight and the decreased gastrointestinal propulsion rate and decreased c-kit IR-positive cell rate were reversed (P < 0.01). CONCLUSION: Zhuang-medicine medicated-thread moxibustion therapy can improve gastrointestinal function in DGP rats, which may be associated with its effect in up-regulating the expression of c-kit IR-positive ICC.

The short-term effects of acupuncture on patients with diabetic gastroparesis: a randomised crossover study.

BACKGROUND: Acupuncture may improve gastrointestinal symptoms in patients with various disorders, but its efficacy in diabetic gastroparesis is unclear. OBJECTIVE: To evaluate the short-term effects of acupuncture on gastric emptying and gastroparesis symptoms in patients with diabetic gastroparesis. METHODS: In a single-blind controlled crossover trial, 25 patients with diabetic gastroparesis were randomly assigned to undergo 1 week of real acupuncture (RA) treatment followed by 1 week of sham acupuncture (SA) treatment, or vice versa, with a washout of 1 month in between. Before and after each intervention, gastric retention, the Gastroparesis Cardinal Symptom Index (GCSI), fasting blood glucose (FBG) and HbA1c levels were measured. RESULTS: 21 patients completed the study. Compared with SA treatment, RA treatment was associated with significantly greater reductions in gastric retention at 2 h (-11.1±7.0%; 95% CI -13.6% to -6.2%; p<0.01) and at 4 h (-5.0±2.8%; 95% CI -6.0% to -0.2%; p=0.04) and in GCSI score (-8.0±3.4; 95% CI -8.4 to -2.8; p<0.01). There were no significant differences in FBG and HbA1c levels between RA and SA treatments. CONCLUSIONS: In patients with diabetic gastroparesis, 1 week of short-term manual acupuncture reduces gastric retention and improves gastroparesis symptoms.

Glucocorticoids induce gastroparesis in mice through depletion of l-arginine.

Glucocorticoids (GCs) constitute a highly pleiotropic class of drugs predominantly employed in the treatment of inflammatory diseases. In our search for new mechanisms of action, we identified a hitherto unknown effect of GCs in the gastrointestinal tract. We found that oral administration of dexamethasone (Dex) to mice caused an enlargement of the stomach due to the induction of gastroparesis and that this effect was abolished in GR(dim) mice carrying the A458T mutation in the GC receptor (GR). Gastroparesis was unrelated to the enhanced gastric acid secretion observed after Dex treatment, although both effects were mediated by the same molecular mechanism of the GR. Using conditional GR-knockout mice, we could further rule out that GC effects on enterocytes or myeloid cells were involved in the induction of gastroparesis. In contrast, we found that Dex upregulated arginase 2 (Arg2) in the stomach both at the mRNA and protein level. This suggests that GC treatment leads to a depletion of l-arginine thereby impeding the production of nitric oxide (NO), which is required for gastric motility. We tested this hypothesis by supplementing the drinking water of the mice with exogenous l-arginine to compensate for the presumed shortage of this major substrate of NO synthases. Importantly, this measure completely prevented both the enlargement of the stomach and the induction of gastroparesis after Dex treatment. Our findings raise considerations of combining orally applied GCs with l-arginine to improve tolerability of GC treatment and provide a possible explanation for the antiemetic effects of GCs widely exploited in chemotherapy.

Benefits of acupuncture for diabetic gastroparesis: a comparative preliminary study.

OBJECTIVES: The aim of this preliminary study was to compare the effectiveness of domperidone and acupuncture for the management of diabetic gastroparesis. METHODS: This was a preliminary, prospective non-randomised, unblinded case-crossover study conducted in patients with longstanding, uncontrolled diabetes mellitus and gastroparesis. All patients received domperidone (20 mg four times a day) for 12 weeks, followed by a 2-3 week washout period, and then biweekly acupuncture treatments for 8 weeks. Gastric emptying rate, glucose and glycated haemoglobin (HbA1C) levels were measured at start and end of each treatment period. At each of these timepoints patients completed the Gastroparesis Cardinal Symptom Index (GCSI), the Satisfaction with Life Scale (SWLS), and the Short-Form 36 Health Survey Update (SF-36). RESULTS: The trial was curtailed after only eight participants could be recruited in 3 years. The mean age of patients was 57.1±9.9 years, the male:female ratio was 1:7 and mean body mass index (kg/m(2)) was 25.2±1.2. There was no change in any of the outcome parameters after treatment with domperidone. Acupuncture was associated with a decrease in scores for almost all cardinal symptoms of the GCSI, as well as in increased total score on the SWLS (p=0.002) and the social functioning domain of the SF-36 (p=0.054). Acupuncture did not lead to an improvement in gastric emptying, or glucose control from baseline. CONCLUSIONS: Acupuncture treatment may lead to symptomatic improvement in patients with diabetic gastroparesis. Within the limitations of this preliminary, non-randomised and unblinded study, it appears that this effect may be due to non-specific mechanisms.

Synchronized gastric electrical stimulation improves vagotomy-induced impairment in gastric accommodation via the nitrergic pathway in dogs.

Impaired gastric accommodation and gastric dysrhythmia are common in gastroparesis and functional dyspepsia. Recent studies have shown that synchronized gastric electrical stimulation (SGES) accelerates gastric emptying and enhances antral contractions in dogs. The aim of this study was to investigate the effects and mechanism of SGES on gastric accommodation and slow waves impaired by vagotomy in dogs. Gastric tone, compliance, and accommodation as well as slow waves with and without SGES were assessed in seven female regular dogs and seven dogs with bilateral truncal vagotomy, chronically implanted with gastric serosal electrodes and a gastric cannula. We found that 1) vagotomy impaired gastric accommodation that was normalized by SGES. The postprandial increase in gastric volume was 283.5 +/- 50.6 ml in the controlled dogs, 155.2 +/- 49.2 ml in the vagotomized dogs, and 304.0 +/- 57.8 ml in the vagotomized dogs with SGES. The ameliorating effect of SGES was no longer observed after application of N(omega)-nitro-L-arginine (L-NNA); 2) vagotomy did not alter gastric compliance whereas SGES improved gastric compliance in the vagotomized dogs, and the improvement was also blocked by L-NNA; and 3) vagotomy impaired antral slow wave rhythmicity in both fasting and fed states. SGES at the proximal stomach enhanced the postprandial rhythmicity and amplitude (dominant power) of the gastric slow waves in the antrum. In conclusion, SGES with appropriate parameters restores gastric accommodation and improves gastric slow waves impaired by vagotomy. The improvement in gastric accommodation with SGES is mediated via the nitrergic pathway. Combined with previously reported findings (enhanced antral contractions and accelerated gastric emptying) and findings in this study (improved gastric accommodation and slow waves), SGES may be a viable therapy for gastroparesis.

[Effects of Tangweian granule on 5-HT(2A)R in rat model with diabetic gastroparesis].

OBJECTIVE: To observe the effects of Tangweian granule on 5-HT(2A)R in rat model with diabetic gastroparesis (DGP). METHOD: The rats with diabetic gastroparesis induced by injecting alloxan and giving 200% Radix Rehmanniae preparata were divided into four groups randomly: Tangweian high dosage group, Tangweian low dosage group, motilium control group and the model control group, 10 rats each group. Each group was irrigated with drugs during establishing the model. Additionally, we chose 10 rats by way of normal control group. Further more, Tangweian high dosage group were irrigated stomach with gliclazide 20 mg x kg(-1) and Tangweian granule 31.75 g x kg(-1); Tangweian low dosage group were irrigated stomach with gliclazide 20 mg x kg(-1) and Tangweian granule 15.88 g x kg(-1); motilium control group were irrigated stomach with gliclazide 20 mg x kg(-1) and motilium 3.75 mg x kg(-1) and the model control group were irrigated stomach with distilled water. Then the effects of Tangweian granule on 5-HT(2A)R were observed. RESULT: The curative group had better effects than the control group in lowering the blood sugar and the level of 5-HT(2A)R content (P < 0.01). And there was significant difference between the curative group and control group (P < 0.05). CONCLUSION: It is verified that Tangweian granule has obvious effects on lowering the blood sugar and improving the level of 5-HT(2A)R.