BACKGROUND Diabetic gastroparesis(DGP),characterized by delayed gastric emptying and impaired motility,poses significant therapeutic challenges due to its complex neural and molecular pathophysiology.Emerging evidence...BACKGROUND Diabetic gastroparesis(DGP),characterized by delayed gastric emptying and impaired motility,poses significant therapeutic challenges due to its complex neural and molecular pathophysiology.Emerging evidence suggests that electroacupuncture(EA)at ST36 modulates gastrointestinal function;however,the precise neuromolecular pathways underlying its efficacy in DGP remain incompletely defined.AIM To elucidate the neural mechanisms underlying EA at ST36 improving DGP gastric motility through the nucleus tractus solitarius(NTS)-vagal axis.METHODS The DGP model was established via a single high-dose intraperitoneal injection of 2%streptozotocin combined with an 8-week high-sugar/high-fat diet.Interventions included EA at ST36,pharmacological modulation[choline acetyltransferase(ChAT)agonist polygalacic acid(PA)and inhibitor antagonist alpha-NETA],and subdiaphragmatic vagotomy.Post-intervention observations included body weight and blood glucose levels.Gastric emptying was evaluated using phenol red assays,gastric slow-wave recordings,and dynamic positron emission tomography-computed tomography imaging.Histopathological analysis(hematoxylineosin staining)and molecular assessments(Western blot,immunofluorescence)were performed to quantify gastric smooth muscle-associated factors[neuronal nitric oxide synthase(nNOS),cluster of differentiation 117(C-kit),stem cell factor(SCF)]and vagal targets[ChAT,α7 nicotinic acetylcholine receptor(α7nAChR)]in the ST36 acupoint region,L4-L6 spinal segments,and NTS.Gastrointestinal peptides[gastrin(Gas),motilin(MLT)and vasoactive intestinal peptide(VIP)]were measured via enzyme-linked immunosorbent assay.RESULTS The study found that EA significantly increased the rate of gastric emptying,restored the slow-wave rhythms of the stomach,and improved the architecture of the smooth muscles in the stomach.This was evidenced by a reduction in inflammatory infiltration and an increase in the expression of nNOS,C-kit,and SCF.Mechanistically,EA activated vagal targets(ChAT andα7nAChR)at ST36,transmitting signals via spinal segments L4-L6 to the NTS,subsequently regulating gastrointestinal peptides(Gas,MLT,VIP)and restoring interstitial cells of Cajal(ICCs)function via subdiaphragmatic vagal efferent pathways.It is crucial to note that subdiaphragmatic vagotomy led to the abrogation of EA-induced enhancements in gastric motility and ICC recovery,thereby confirming the indispensable role of vagal efferent signalling.CONCLUSION EA provides a novel molecular mechanism for improving gastrointestinal motility in DGP via a peripheral stimulation(ST36),spinal afferent(L4-L6),brainstem integration(NTS),vagal efferent(gastric)circuit.展开更多
BACKGROUND Diabetic gastroparesis(DGP)disrupts gastric motility.Electroacupuncture(EA)at Zusanli(ST36)may alleviate DGP symptoms via neural pathways.AIM To investigate how EA current intensities at ST36 regulate neura...BACKGROUND Diabetic gastroparesis(DGP)disrupts gastric motility.Electroacupuncture(EA)at Zusanli(ST36)may alleviate DGP symptoms via neural pathways.AIM To investigate how EA current intensities at ST36 regulate neural pathways and improve gastric motility in DGP models.METHODS A DGP model was established using intraperitoneal injection of streptozotocin.Gastrointestinal motility was measured in rats after 2 weeks of continuous EA at ST36.Current intensity was selected as 0.5 mA,1 mA,and 3 mA.Gastric electrodynamics were detected by recording and analyzing the number of gastric discharges.The gastric emptying rate and propulsion rate of the small intestine were measured to assess dynamic gastrointestinal function.Hematoxylin-eosin staining was conducted to measure histopathological changes in the gastric sinus.Reverse transcription-polymerase chain reaction was conducted to determine mRNA levels of Rho guanine nucleotide-binding protein A and Rho-associated coiled-coil forming protein kinase.Western blotting was conducted to determine the expression levels of choline acetyltransferase,tyrosine hydroxylase,Rho guanine nucleotide-binding protein A,and Rho-associated coiled-coil forming protein kinase.Immunofluorescence staining in the stomach was conducted to detect the distribution of C-kit,an interstitial cell of Cajal marker.An enzymelinked immunosorbent assay was conducted to detect serum levels of acetylcholine and norepinephrine.RESULTS Treatment with EA improved gastric emptying and gastric smooth muscle disorders in rats with DGP,mitigated pathological damage,and restored the function of interstitial cells of Cajal.In addition,different current intensities of EA affected gastrointestinal function of rats with DGP.The 0.5 mA,1 mA,and 3 mA EA groups all improved gastrointestinal function.0.5 mA EA increased acetylcholine levels by increasing protein expression of choline acetyltransferase(P<0.05),thereby upregulating vagus nerve activity and enhancing parasympathetic nerve regulation.3 mA EA increased norepinephrine levels(P<0.05)by increasing protein expression of tyrosine hydroxylase,thereby activating the sympathetic nervous pathway.1 mA coordinated the function of the vagus and sympathetic nerves to improve gastrointestinal motility.CONCLUSION EA with ST36 improved gastric motility in rats with DGP.0.5 mA EA activated the vagus nerve,while 3 mA EA regulated gastrointestinal motility by activating the sympathetic nerves.展开更多
基金Supported by the Natural Science Foundation of Hunan Province,China,No.2023JJ30462Hunan Provincial Department of Science and Technology,No.2023SK2045,No.22JBZ007 and No.Z2023JB01Graduate Research and Innovation Projects of Hunan Province,No.2024CX031.
文摘BACKGROUND Diabetic gastroparesis(DGP),characterized by delayed gastric emptying and impaired motility,poses significant therapeutic challenges due to its complex neural and molecular pathophysiology.Emerging evidence suggests that electroacupuncture(EA)at ST36 modulates gastrointestinal function;however,the precise neuromolecular pathways underlying its efficacy in DGP remain incompletely defined.AIM To elucidate the neural mechanisms underlying EA at ST36 improving DGP gastric motility through the nucleus tractus solitarius(NTS)-vagal axis.METHODS The DGP model was established via a single high-dose intraperitoneal injection of 2%streptozotocin combined with an 8-week high-sugar/high-fat diet.Interventions included EA at ST36,pharmacological modulation[choline acetyltransferase(ChAT)agonist polygalacic acid(PA)and inhibitor antagonist alpha-NETA],and subdiaphragmatic vagotomy.Post-intervention observations included body weight and blood glucose levels.Gastric emptying was evaluated using phenol red assays,gastric slow-wave recordings,and dynamic positron emission tomography-computed tomography imaging.Histopathological analysis(hematoxylineosin staining)and molecular assessments(Western blot,immunofluorescence)were performed to quantify gastric smooth muscle-associated factors[neuronal nitric oxide synthase(nNOS),cluster of differentiation 117(C-kit),stem cell factor(SCF)]and vagal targets[ChAT,α7 nicotinic acetylcholine receptor(α7nAChR)]in the ST36 acupoint region,L4-L6 spinal segments,and NTS.Gastrointestinal peptides[gastrin(Gas),motilin(MLT)and vasoactive intestinal peptide(VIP)]were measured via enzyme-linked immunosorbent assay.RESULTS The study found that EA significantly increased the rate of gastric emptying,restored the slow-wave rhythms of the stomach,and improved the architecture of the smooth muscles in the stomach.This was evidenced by a reduction in inflammatory infiltration and an increase in the expression of nNOS,C-kit,and SCF.Mechanistically,EA activated vagal targets(ChAT andα7nAChR)at ST36,transmitting signals via spinal segments L4-L6 to the NTS,subsequently regulating gastrointestinal peptides(Gas,MLT,VIP)and restoring interstitial cells of Cajal(ICCs)function via subdiaphragmatic vagal efferent pathways.It is crucial to note that subdiaphragmatic vagotomy led to the abrogation of EA-induced enhancements in gastric motility and ICC recovery,thereby confirming the indispensable role of vagal efferent signalling.CONCLUSION EA provides a novel molecular mechanism for improving gastrointestinal motility in DGP via a peripheral stimulation(ST36),spinal afferent(L4-L6),brainstem integration(NTS),vagal efferent(gastric)circuit.
基金Supported by National Natural Science Foundation of China,No.82205298Natural Science Foundation of Hunan Province,No.2023JJ30462+1 种基金Hunan Provincial Department of Science and Technology,No.2023SK2045,No.22JBZ007,No.Z2023XJYQ07,No.B2024007,and No.Z2023JB012024 Graduate Innovation Topics,No.2024CX031.
文摘BACKGROUND Diabetic gastroparesis(DGP)disrupts gastric motility.Electroacupuncture(EA)at Zusanli(ST36)may alleviate DGP symptoms via neural pathways.AIM To investigate how EA current intensities at ST36 regulate neural pathways and improve gastric motility in DGP models.METHODS A DGP model was established using intraperitoneal injection of streptozotocin.Gastrointestinal motility was measured in rats after 2 weeks of continuous EA at ST36.Current intensity was selected as 0.5 mA,1 mA,and 3 mA.Gastric electrodynamics were detected by recording and analyzing the number of gastric discharges.The gastric emptying rate and propulsion rate of the small intestine were measured to assess dynamic gastrointestinal function.Hematoxylin-eosin staining was conducted to measure histopathological changes in the gastric sinus.Reverse transcription-polymerase chain reaction was conducted to determine mRNA levels of Rho guanine nucleotide-binding protein A and Rho-associated coiled-coil forming protein kinase.Western blotting was conducted to determine the expression levels of choline acetyltransferase,tyrosine hydroxylase,Rho guanine nucleotide-binding protein A,and Rho-associated coiled-coil forming protein kinase.Immunofluorescence staining in the stomach was conducted to detect the distribution of C-kit,an interstitial cell of Cajal marker.An enzymelinked immunosorbent assay was conducted to detect serum levels of acetylcholine and norepinephrine.RESULTS Treatment with EA improved gastric emptying and gastric smooth muscle disorders in rats with DGP,mitigated pathological damage,and restored the function of interstitial cells of Cajal.In addition,different current intensities of EA affected gastrointestinal function of rats with DGP.The 0.5 mA,1 mA,and 3 mA EA groups all improved gastrointestinal function.0.5 mA EA increased acetylcholine levels by increasing protein expression of choline acetyltransferase(P<0.05),thereby upregulating vagus nerve activity and enhancing parasympathetic nerve regulation.3 mA EA increased norepinephrine levels(P<0.05)by increasing protein expression of tyrosine hydroxylase,thereby activating the sympathetic nervous pathway.1 mA coordinated the function of the vagus and sympathetic nerves to improve gastrointestinal motility.CONCLUSION EA with ST36 improved gastric motility in rats with DGP.0.5 mA EA activated the vagus nerve,while 3 mA EA regulated gastrointestinal motility by activating the sympathetic nerves.
