Ghrelin improves delayed gastrointestinal transit in alloxan-induced diabetic mice

AIM: To investigate the effects of ghrelin on delayed gastrointestinal transit in alloxan-induced diabetic mice. METHODS: A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups: normal mice group and diabetic mice group treated with ghrelin at doses of 0, 20, 50, 100 and 200 μg/kg ip. Gastric emptying (GE), intestinal transit (IT), and colonic transit (CT) were studied in mice after they had a phenol red meal following injection of ghrelin. Based on the most effective ghrelin dosage, atropine was given at 1 mg/kg 15 min before the ghrelin injection for each measurement. The mice in each group were sacrificed 20 min later and their stomachs, intestines, and colons were harvested immediately. The amount of phenol red was measured. Percentages of GE, IT, and CT were calculated. RESULTS: Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice (22.9 ± 1.4 vs 28.1 ± 1.3, 33.5 ± 1.2 vs 43.2 ± 1.9, 29.5 ± 1.9 vs 36.3 ± 1.6, P < 0.05). In the diabetic mice, ghrelin improved both GE and IT, but not CT. The most effective dose of ghrelin was 100 μg/kg and atropine blocked the prokinetic effects of ghrelin on GE and IT.CONCLUSION: Ghrelin accelerates delayed GE and IT but has no effect on CT in diabetic mice. Ghrelin may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.

Effect of intestinal transit on the formation of cholesterol gallstones in hamsters

BACKGROUND: The effect of 'intestinal transit' has become a new field of interest in the study of the pathogenesis of cholesterol gallstones. This study was undertaken to further test this notion and ascertain the relationship between impaired intestinal transit function and cholesterol gallstones. METHODS: A total of 64 hamsters were divided into 2 groups, experimental and control. Each was subdivided into 4 subgroups for sacrifice at different time. A high-cholesterol diet and a standard diet were fed to each group. The geometric center, which represents the intestinal transit function was calculated. RESULTS: The growth of all hamsters was normal. Cholesterol gallstones were found in 2 hamsters at the end of the 4th week. The geometric center values for the experimental and control groups were 2.3891 +/- 0.3923 vs. 2.7730 +/- 0.5283, at the end of week 3; 1.8148 +/- 0.4312 vs. 3.2294 +/- 1.1613 at week 4; 1.8451 +/- 0.3700 vs. 2.9075 +/- 0.3756 at week 5; and 1.8025 +/- 0.3413 vs. 3.0920 +/- 0.5622 at week 6. CONCLUSION: A high cholesterol diet can significantly reduce the intestinal transit function and facilitate the formation of cholesterol gallstones.

An inherent acceleratory effect of insulin on small intestinal transit and its pharmacological characterization in normal mice

AIM： To study an inherent effect of insulin on small intestinal transit and to explore involvement of various systems/mechanisms in normal mice. METHODS： Insulin at the doses of 2 μU/kg, 2 mU/kg, 2 U/kg or vehicle was subcutaneously administered to four groups of overnight fasted normal male mice. Blood glucose （BG） levels were measured 2 min before insulin administration and 2 min before sacrificing the animals for the measurement of small intestinal transit （SIT）. Charcoal meal was administered （0.3 mL） intragastrically 20 min after insulin administration and animals were sacrificed after 20 min and SIT was determined. For exploration of the various mechanisms involved in insulin-induced effect on SIT, the dose of insulin which can produce a significant acceleration of SIT without altering BG levels was determined. The following drugs, atropine （1 mg/kg）, clonidine （0.1 mg/kg）, ondansetron （1 mg/kg）, naloxone （5 mg/kg）, verapamil （8 mg/kg） and glibenclamide （10 mg/kg）, were administered intravenously 10 min prior to the administration of insulin （2 μU/kg）. RESULTS： The lower doses of insulin （2 μU/kg and 2 mU/kg） produced a significant acceleration of SIT from 52.0% to 70.7% and 73.5% without lowering blood glucose levels （P〈0.01）, while the highest dose of insulin （2 U/kg） produced a fall in blood glucose levels which was also associated with significant acceleration of SIT （P〈0.01）. After pretreatment of insulin （2 μU/kg） group with atropine, insulin could reverse 50% of the inhibition produced by atropine. In clonidine-pretreated group, insulin administration could reverse only 37% of the inhibition produced by clonidine and inhibition of SIT was significant compared with vehicle ＋ insulintreated group, i.e. from 74.7% to 27.7% （P〈0.01）. In ondansetron-pretreated group, insulin administration could produce only mild acceleration of SIT （23.5%）. In naloxone-pretreated group, insulin administration could significantly reverse the inhibition of SIT produced by naloxone when compared with naloxoneperse group, i.e. from 32.3% to 53.9% （P〈0.01）. In verapamil-pretreated group, insulin administration could only partially reverse the inhibition （65%）. In glibenclamide-pretreated group, insulin administration produced further acceleration of SIT （12.2%）. CONCLUSION： Insulin inherently possesses an acceleratory effect on SIT in normal mice. Adrenergic and cholinergic systems can play a significant role. Calcium channels and opioidergic system can play a supportive role; in addition, enhancement of endogenous insulin release can augment the effect of exogenously administered insulin on SIT.

Jianqu,a traditional Chinese medicine,alleviates functional dyspepsia in high-calorie and high-protein diet mice

Background:Jianqu has been used to alleviate symptoms in patients with functional dyspepsia,but its specific anti-functional dyspepsia effect is still unclear.Therefore,our study aimed to investigate the impact of Jianqu on functional dyspepsia in mice.Methods:The phytochemical profile of Jianqu was analyzed by UPLC-Q-TOF-MS.Subsequently,Kunming mice were fed a high-calorie or high-protein diet(HCHP)for 7 days,and then orally treated with vehicle or Jianqu(1.62 g/kg body weight(b.w.)and 3.25 g/kg b.w.)for 10 days.A carbon powder solution was used to detect the gastric emptying and intestinal transit rate.The pathological changes in stomach and duodenum were evaluated by hematoxylin-eosin staining.The occludin,claudin-1,ZO-1 and CD45 expression was measured by immunocytochemical staining.Importantly,the serum gastrointestinal hormones were detected by ELISA.In addition,the gut microbiota composition was determined using 16S rRNA gene sequencing.The cecal short chain fatty acids were assessed by gas chromatography.Results:In general,17 phytochemical compounds were identified from Jianqu,which significantly improved the gastric emptying rate and intestinal transit rate(p<0.01),increased the body weight and food intake(p<0.0001)in HCHP mice as well.Though HCHP did not cause significant pathological lesions in the gastrointestinal tract,increased the expression of CD45 in the duodenum(p<0.05)was observed.Notably,Jianqu attenuated this abnormal expression of CD45(p<0.05).The levels of serum gastrointestinal hormones were significantly normalized by Jianqu intervention(p<0.05).Moreover,Jianqu increased the relative abundance of Roseburia as well as short chain fatty acids levels in cecum(p<0.05).Conclusion:The present results showed that Jianqu alleviated dyspeptic symptoms in HCHP mice possibly through reducing the duodenal leukocyte infiltration,and regulating the expression of gastrointestinal hormones.These effects may be partly related to the increasing cecal short chain fatty acids levels probably via gut microbial modulation.

Effects of Hwangryunhaedok-tang on gastrointestinal motility function in mice

AIM To investigate the effects of Hwangryunhaedok-tang(HHT) on gastrointestinal(GI) motility in mice.METHODS The effects of a boiling water extract of HHT(HHTE) on GI motility were investigated by calculating percent intestinal transit rates(ITR%) and gastric emptying(GE) values using Evans Blue and phenol red, respectively, in normal mice and in mice with experimentally induced GI motility dysfunction(GMD). In addition, the effects of the four components of HHT, that is, Gardeniae Fructus(GF), Scutellariae Radix(SR), Coptidis Rhizoma(CR), and Phellodendri Cortex(PC), on GI motility were also investigated.RESULTS In normal ICR mice, ITR% and GE values were significantly and dose-dependently increased by the intragastric administration of HHTE(0.1-1 g/kg). The ITR% values of GMD mice were significantly lower than those of normal mice, and these reductions were significantly and dose-dependently inhibited by HHTE(0.1-1 g/kg). Additionally, GF, CR, and PC dosedependently increased ITR% and GE values in normal and GMD mice.CONCLUSION These results suggest that HHT is a novel candidate for the development of a gastroprokinetic agent for the GI tract.

Prokinetic effects of a ghrelin receptor agonist GHRP-6 in diabetic mice

AIM： To investigate the effects of a ghrelin receptor agonist GHRP-6 on delayed gastrointestinal transit in alloxan-induced diabetic mice. METHODS： A diabetic mouse model was established by intraperitoneal injection with alloxan. Mice were randomized into two main groups： normal mice and diabetic mice treated with GHRP-6 at doses of 0, 20, 50, 100 and 200 μg/kg ip. Gastric emptying （GE）, intestinal transit （IT）, and colonic transit （CT） were studied in mice after they had a phenol red meal following injection of GHRP-6. Based on the most effective GHRP-6 dosage, atropine was given at 1 mg/kg for 15 rain before the GHRP-6 injection for each measurement. The mice in each group were sacrificed 20 min later and the percentages of GE, IT, and CT were calculated. RESULTS： Percentages of GE, IT, and CT were significantly decreased in diabetic mice as compared to control mice. In the diabetic mice, GHRP-6 improved both GE and IT, but not CT. The most effective dose of GHRP-6 was 200 μg/kg and atropine blocked the prokinetic effects of GHRP-6 on GE and IT. CONCLUSION： GHRP-6 accelerates delayed GE and IT, but has no effect on CT in diabetic mice. GHRP-6 may exert its prokinetic effects via the cholinergic pathway in the enteric nervous system, and therefore, has therapeutic potential for diabetic patients with delayed upper gastrointestinal transit.

Extended Fasting Durations Delayed Gastric Emptying and Colonic Motility in Normal Male Rats

Background: Previous studies on fasting and gastrointestinal motility were reported with information lacking concerning prolonged continuous fasting and gastrointestinal motility. This study investigated the effect of prolonged fasting duration on gastrointestinal motility. Methods: Forty-five (45) male Wistar rats, with body weights between 180 - 200 g were used. They were randomly assigned into three (3) groups. Group1: control (rats fasted for 18 h—common duration of fasting for motility studies), groups 2 and 3 fasted for 48 and 72 h respectively. Five (5) rats per experiment and per group were considered. Blood glucose was determined by glucose oxidase method, gastric emptying was assessed by hydrated carbohydrate meal, intestinal motility by charcoal meal, and colonic motility was assessed using bead test. Data were reported in Mean ± SEM and analyzed with one-way ANOVA. Differences in results were considered significant at p ≤ 0.05. Results: There was no significant change in the blood glucose level (mmol/L) of rats in the 48 h group (2.94 ± 0.35) and 72 h group (3.20 ± 0.32) as compared with the control (3.62 ± 0.19). There was a significant decrease in the rate of gastric emptying (g) in the 72 h group (0.20 ± 0.08) compared with the control (0.64 ± 0.16). The intestinal transit (cm) in the 48 h group (67.54 ± 6.15) and 72 h group (72.10 ± 7.60) increased significantly when compared with the control (42.14 ± 3.14). There was a significant decrease in the colonic motility time (Sec.) in the 48 h group (2707 ± 864.1) and 72 h group (6363 ± 968.1) when compared with the control (263.8 ± 64.26). Conclusion: Extended fasting durations decrease the rate of gastric emptying and colonic motility. It suggests that extended fasting durations could be beneficial in intestinal spasms or where the gut is required to relax.

Acupuncture and Moxibustion Inhibited Intestinal Epithelial-Mesenchymal Transition in Patients with Crohn's Disease Induced by TGF-β1/Smad3/Snail Pathway:A Clinical Trial Study

Objective:To explore whether acupuncture combined with moxibustion could inhibit epithelialmesenchymal transition in Crohn’s disease by affecting the transforming growth factorβ1(TGF-β1)/Smad3/Snail pathway.Methods:Sixty-three patients with Crohn’s disease were randomly divided into an observation group(31 cases)receiving moxibustion at 43℃ combined with acupuncture,and a control group(32 cases)receiving moxibustion at 37℃combined with sham acupuncture using a random number table.Patients were treated for12 weeks.Crohn’s Disease Activity Index(CDAI)was used to evaluate disease activity.Hematoxylin-eosin staining and transmission electron microscopy were utilized to observe the morphological and ultrastructural changes.Immunohistochemistry was used to detect the expression of transforming growth factorβ1(TGF-β1),TβR1,TβR2,Smad3,Snail,E-cadherin and fibronectin in intestinal mucosal tissues.Results:The decrease of the CDAI score,morphological and ultrastructural changes were more significant in observation group.The expression levels of TGF-β1,TβR2,Smad3,and Snail in the observation group were significantly lower than those before the treatment(P<0.05 or P<0.01).After treatment,the expression levels of TGF-β1,TβR2,and Snail in the observation group were significantly lower than those in the control group(all P<0.05);compared with the control group,the expression of fibronectin in the observation group was significantly decreased,and the expression of E-cadherin was significantly increased(all P<0.05).Conclusions:Moxibustion at 43℃combined with acupuncture may suppress TGF-β1/Smad3/Snail pathway-mediated epithelial-mesenchymal transition of intestinal epithelial cells in Crohn’s disease patients by inhibiting the expression levels of TGF-β1,TβR2,Smad3,and Snail.(Registration No.ChiCTR-IIR-16007751).

Influence of Musa Sapientum L. on Pharmacokinetic of Metformin in Diabetic Gastroparesis

Objective： To investigate the effect of Musa sapientum L. （MS） bark juice in diabetic gastroparesis and its effect on pharrnacokinetic of metformin （MET）. Methods： Diabetes was induced in rats by administering alloxan （120 mg/kg） saline solution and maintained for 8 week. All the 18 Sprague-Dawley rats were divided into three groups （n=6 in each group）： normal control, diabetic control and MS bark juice. Assessment of diabetes was done by glucose oxidase-peroxidase method on the 3rd day of alloxan administration. The effects of MS bark juice （100 mL/kg） on gastric emptying time, intestinal transit time, contractility of fundus and pylorus as well as gastdc acid secretion in chronic diabetic rats were observed after 8 weeks of aUoxan administration. The effect of MS bark juice on the pharmacokinetic of orally administered single dose of MET （350 mg/kg） was evaluated on the 57th day of protocol. Any drugs that may reduce the blood glucose level or influence the fibrinolytic system were not used in this study. Results： The MS bark juice significantly reduced the blood glucose level in the diabetic rats （P〈0.01）. There was significant decrease in the pylorus motility and increase in the gastric emptying time, intestinal transit time, contractility of fundus, gastric acid secretion in the MS bark juice treated group （P〈0.01）. There was significant decrease in the time at which drug at a maximum concentration, haft life of drug and increase in the maximum concentration of drug in the plasma of MET in MS bark juice treated group as compared to diabetic control group （P〈0.01）. Conclusion： MS bark juice effectively manages diabetic gastroparesis and thereby improves the bioavailabilty of MET when administered with MS bark iuice.

Effect of Cassia nomame on Small Intestine Movement, Diuresis,and Anti-inflammation in Rats

Objective To investigate the preliminary pharmacological screening of Cassia nomame.Methods The effect of aqueous extract from C.nomame on gastrointestinal motor function was investigated by assessing the intestinal transit rate(ITR)of charcoal modeled into gastrointestinal motility dysfunction(GMD)by the administration of dopamine,atropine,or noradrenaline to the rats,respectively.Diuresis was studied in vivo by estimating the urine output.The anti-inflammatory activity was expressed as the percentage of swelling reduction by comparison on the mean thickness of ear swelling in mice.Results The ITR in these GMD animals was significantly retarded compared to that in normal animals.The retardation,however,was significantly inhibited by the ig administration of C.nomame(2 g/kg)for all GMD animals.The results suggested that C.nomame had the potential for development into a prokinetic agent that could prevent or alleviate GMD in patients.C.nomame increased urine output and suppressed significantly ear swelling induced by dirnethyl benzene in mice.Conclusion C.nomame could increase the gastrointestinal contractile activity of rats and has the effects of diuresis and anti-inflammation.