Background:The development of ketamine-like rapid antidepressants holds promise for enhancing the therapeutic efficacy of depression,but the underlying cellular and molecular mechanisms remain unclear.Implicated in de...Background:The development of ketamine-like rapid antidepressants holds promise for enhancing the therapeutic efficacy of depression,but the underlying cellular and molecular mechanisms remain unclear.Implicated in depression regulation,the neuropeptide pituitary adenylate cyclase-activating polypeptide(PACAP)is investigated here to examine its role in mediating the rapid antidepressant response.Methods:The onset of antidepressant response was assessed through depression-related behavioral paradigms.The signaling mechanism of PACAP in the hippocampal dentate gyrus(DG)was evaluated by utilizing site-directed gene knockdown,pharmacological interventions,or optogenetic manipulations.Overall,446 mice were used for behavioral and molecular signaling testing.Mice were divided into control or experimental groups randomly in each experiment,and the experimental manipulations included:chronic paroxetine treatments(4 d,9 d,14 d)or a single treatment of ketamine;social defeat or lipopolysaccharides-injection induced depression models;different doses of PACAP(0.4 ng/site,2 ng/site,4 ng/site;microinjected into the hippocampal DG);pharmacological intra-DG interventions(CALM and PACAP6-38);intra-DG viral-mediated PACAP RNAi;and opotogenetics using channelrhodopsins 2(ChR2)or endoplasmic natronomonas halorhodopsine 3.0(eNpHR3.0).Behavioral paradigms included novelty suppressed feeding test,tail suspension test,forced swimming test,and sucrose preference test.Western blotting,ELISA,or quantitative real-time PCR(RT-PCR)analysis were used to detect the expressions of proteins/peptides or genes in the hippocampus.Results:Chronic administration of the slow-onset antidepressant paroxetine resulted in an increase in hippocampal PACAP expression,and intra-DG blockade of PACAP attenuated the onset of the antidepressant response.The levels of hippocampal PACAP expression were reduced in both two distinct depression animal models and intra-DG knockdown of PACAP induced depression-like behaviors.Conversely,a single infusion of PACAP into the DG region produced a rapid and sustained antidepressant response in both normal and chronically stressed mice.Optogenetic intra-DG excitation of PACAP-expressing neurons instantly elicited antidepressant responses,while optogenetic inhibition induced depression-like behaviors.The longer optogenetic excitation/inhibition elicited the more sustained antidepressant/depression-like responses.Intra-DG PACAP infusion immediately facilitated the signaling for rapid antidepressant response by inhibiting calcium/calmodulin-dependent protein kinaseⅡ(CaM KⅡ)-eukaryotic elongation factor 2(eEF2)and activating the mammalian target of rapamycin(mTOR).Pre-activation of CaMKⅡsignaling within the DG blunted PACAP-induced rapid antidepressant response as well as eEF2-mTOR-brain-derived neurotrophic factor(BDNF)signaling.Finally,acute ketamine treatment upregulated hippocampal PACAP expression,whereas intraDG blockade of PACAP signaling attenuated ketamine’s rapid antidepressant response.Conclusions:Activation of hippocampal PACAP signaling induces a rapid antidepressant response through the regulation of CaMKⅡinhibition-governed eEF2-mTOR-BDNF signaling.展开更多
目的:探讨J型针刀通过PACAP-cAMP-PKA信号通路改善脊髓损伤后神经源性膀胱大鼠逼尿肌的作用机制。方法:36只SD雄性大鼠随机分为6组:空白组、假手术组、模型组、J型针刀治疗组、治疗+Bupivacaine抑制剂组、治疗+H-89抑制剂组,各6只。采...目的:探讨J型针刀通过PACAP-cAMP-PKA信号通路改善脊髓损伤后神经源性膀胱大鼠逼尿肌的作用机制。方法:36只SD雄性大鼠随机分为6组:空白组、假手术组、模型组、J型针刀治疗组、治疗+Bupivacaine抑制剂组、治疗+H-89抑制剂组,各6只。采用脊髓横断法制作神经源性膀胱模型。空白组为正常SD大鼠;假手术组为切开相关部位组织,无脊髓切断;其余4组予以手术脊髓切断造模。J型针刀治疗组造模后第19天予J型针刀针刺大鼠次髎穴,2 d 1次,共治疗7次。干预结束后各组行HE染色观察膀胱逼尿肌组织形态变化,Elisa检测膀胱逼尿肌组织中c AMP、PKA含量,免疫组化检测膀胱逼尿肌组织中PACAP38蛋白表达,Western blot检测膀胱逼尿肌组织中PKA、p-MLC蛋白表达。结果:HE染色结果显示,与空白组相比,模型组中膀胱逼尿肌组织严重坏死,可见大量炎症细胞浸润;与模型组相比,J型针刀治疗组、治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组均有不同程度坏死组织修复情况。免疫组化检测PACAP38蛋白表达在模型组中表达量最低,针刀治疗之后,PACAP38表达量均不同程度上调;与J型针刀治疗组相比,治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组PACAP38蛋白表达均不同程度下调(P<0.05),但高于模型组(P<0.05)。Elisa检测结果显示,cAMP、PKA表达量模型组显著下调(P<0.05),J型针刀治疗组与模型组比显著上调(P<0.05),治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组比无显著差异(P>0.05)。WB结果显示:与空白组相比,模型组PKA、p-MLC蛋白表达上调;针刀治疗组表达量下调,其中PKA蛋白表达有显著性(P<0.05),p-MLC蛋白表达无显著性(P>0.05)。与J型针刀治疗组比,PKA蛋白表达量在治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组中无显著差异(P>0.05),p-MLC蛋白表达量显著下降(P<0.05)。结论:J型针刀针刺次髎穴可改善脊髓损伤后神经源性膀胱大鼠膀胱功能,其机制与J型针刀上调膀胱逼尿肌中PACAP38、cAMP、PKA表达,激活PACAP-cAMP-PKA信号通路,从而促进逼尿肌舒张有关。展开更多
Objective:To elucidate the underlying mechanism and effect of electroacupuncture(EA)on the neurogenic bladder following suprasacral spinal cord injury(ssCI).A rat model of detrusor hyperreflexia after SsCI was establi...Objective:To elucidate the underlying mechanism and effect of electroacupuncture(EA)on the neurogenic bladder following suprasacral spinal cord injury(ssCI).A rat model of detrusor hyperreflexia after SsCI was established to examine the urodynamics,detrusor muscle tissue morphology,the protein and mRNA expression levels of pituitary adenylate cyclase activating peptide(PACAP)and its receptor PAC1R,and cyclic adenosine monophosphate(cAMP)content in the detrusor muscle with a focus on the PACAPcAMP signaling pathway.Method:A total of 72 female SD rats were randomized into control group and sham operation group(n=12 per group)by using a random number table.The remaining 48 rats were established into the model of detrusor hyperreflexia after SsCI.After successful modeling,these rats were randomly assigned to model,EA,and EA+PACAP6-38 groups(n=12 per group).The unsuccessful modeled rats were used for exploratory observation.For the rats in EA group,"Ciliao(BL32)""Zhongji(CV3)",and"Sanyinjiao(SP6)"were needled and stimulated by EA.The PACAP receptor antagonist PACAP6-38 was administered intraperitoneally in the EA+PACAP6-38 group before EA,and EA was applied for seven consecutive days.After treatment,the urodynamics of the rats were analyzed,and hematoxylin and eosin staining was used to examine rat bladder detrusor tissue morphology.The expressions of PACAP-38 and PAC1R were detected by immunohistochemistry and Western blot.The mRNA expression levels of PACAP-38 and PAC1R were examined by RT-qPCR,while cAMP content was detected by ELISA.Results:(1)Compared with sham operation group,it was exhibited disarray in the transitional epithelium cells of the bladder in the modeled rats.The intercellular space was significantly widened,accompanied by inflammatory cell infiltration and noticeable tissue edema.Both the bladder initial pressure and leak point pressure of the rats were higher(P<0.01),whereas the maximum cystometric capacity and bladder compliance were lower(P<0.01).The protein and mRNA expression levels of PACAP-38 and PAC1R in the detrusor muscle,together with the cAMP content,were lower(P<0.05).(2)Compared with the model rats,the EA group showed reduced inflammatory response in the detrusor muscle tissue,with decreased monocyte infiltration and less severe tissue edema.The bladder smooth muscle cells exhibited increased integrity,and there was decreased cellular tissue edema,inflammatory cell infiltration,and fibroplasia.The bladder initial pressure and leak point pressure were lower(P<0.05),while the maximum cystometric capacity and bladder compliance were higher(P<0.01).The protein and mRNA expression levels of PACAP-38 and PAC1R in the detrusor muscle,along with the cAMP content,were higher(P<0.05).(3)Compared to the EA group,the EA+PACAP6-38 group showed a less organized arrangement of muscle fibers in the detrusor muscle tissue,larger intercellular space,monocyte infltration,and considerable tissue edema.The changes in bladder initial pressure and leak point pressure were not significant(P>0.05),while the maximum cystometric capacity and bladder compliance were lower(P<0.05).The changes in the protein and mRNA expressions of PACAP-38 within the detrusor muscle were not signifcant(P>0.05),whereas the protein and mRNA expressions of PAC1R were reduced(P<0.05),and the cAMP content within the detrusor muscle was lower(P<0.05).Conclusion:EA can ameliorate the uninhibited contractile condition of the detrusor muscle in the bladder following SSCI.By mediating the PACAP-cAMP signaling pathway,it reduces the pathological damage to the detrusor muscle,thereby improving bladder function.展开更多
基金supported by the National Key Research and Development Program of China(2022YFE0201000)the National Natural Science Foundation of China(82174002,82104416,82204652)the High-Level University Development Program of Guangdong Province,and the Guangzhou Key Science and Technology Research and Development Project(202206010109)。
文摘Background:The development of ketamine-like rapid antidepressants holds promise for enhancing the therapeutic efficacy of depression,but the underlying cellular and molecular mechanisms remain unclear.Implicated in depression regulation,the neuropeptide pituitary adenylate cyclase-activating polypeptide(PACAP)is investigated here to examine its role in mediating the rapid antidepressant response.Methods:The onset of antidepressant response was assessed through depression-related behavioral paradigms.The signaling mechanism of PACAP in the hippocampal dentate gyrus(DG)was evaluated by utilizing site-directed gene knockdown,pharmacological interventions,or optogenetic manipulations.Overall,446 mice were used for behavioral and molecular signaling testing.Mice were divided into control or experimental groups randomly in each experiment,and the experimental manipulations included:chronic paroxetine treatments(4 d,9 d,14 d)or a single treatment of ketamine;social defeat or lipopolysaccharides-injection induced depression models;different doses of PACAP(0.4 ng/site,2 ng/site,4 ng/site;microinjected into the hippocampal DG);pharmacological intra-DG interventions(CALM and PACAP6-38);intra-DG viral-mediated PACAP RNAi;and opotogenetics using channelrhodopsins 2(ChR2)or endoplasmic natronomonas halorhodopsine 3.0(eNpHR3.0).Behavioral paradigms included novelty suppressed feeding test,tail suspension test,forced swimming test,and sucrose preference test.Western blotting,ELISA,or quantitative real-time PCR(RT-PCR)analysis were used to detect the expressions of proteins/peptides or genes in the hippocampus.Results:Chronic administration of the slow-onset antidepressant paroxetine resulted in an increase in hippocampal PACAP expression,and intra-DG blockade of PACAP attenuated the onset of the antidepressant response.The levels of hippocampal PACAP expression were reduced in both two distinct depression animal models and intra-DG knockdown of PACAP induced depression-like behaviors.Conversely,a single infusion of PACAP into the DG region produced a rapid and sustained antidepressant response in both normal and chronically stressed mice.Optogenetic intra-DG excitation of PACAP-expressing neurons instantly elicited antidepressant responses,while optogenetic inhibition induced depression-like behaviors.The longer optogenetic excitation/inhibition elicited the more sustained antidepressant/depression-like responses.Intra-DG PACAP infusion immediately facilitated the signaling for rapid antidepressant response by inhibiting calcium/calmodulin-dependent protein kinaseⅡ(CaM KⅡ)-eukaryotic elongation factor 2(eEF2)and activating the mammalian target of rapamycin(mTOR).Pre-activation of CaMKⅡsignaling within the DG blunted PACAP-induced rapid antidepressant response as well as eEF2-mTOR-brain-derived neurotrophic factor(BDNF)signaling.Finally,acute ketamine treatment upregulated hippocampal PACAP expression,whereas intraDG blockade of PACAP signaling attenuated ketamine’s rapid antidepressant response.Conclusions:Activation of hippocampal PACAP signaling induces a rapid antidepressant response through the regulation of CaMKⅡinhibition-governed eEF2-mTOR-BDNF signaling.
文摘目的:探讨J型针刀通过PACAP-cAMP-PKA信号通路改善脊髓损伤后神经源性膀胱大鼠逼尿肌的作用机制。方法:36只SD雄性大鼠随机分为6组:空白组、假手术组、模型组、J型针刀治疗组、治疗+Bupivacaine抑制剂组、治疗+H-89抑制剂组,各6只。采用脊髓横断法制作神经源性膀胱模型。空白组为正常SD大鼠;假手术组为切开相关部位组织,无脊髓切断;其余4组予以手术脊髓切断造模。J型针刀治疗组造模后第19天予J型针刀针刺大鼠次髎穴,2 d 1次,共治疗7次。干预结束后各组行HE染色观察膀胱逼尿肌组织形态变化,Elisa检测膀胱逼尿肌组织中c AMP、PKA含量,免疫组化检测膀胱逼尿肌组织中PACAP38蛋白表达,Western blot检测膀胱逼尿肌组织中PKA、p-MLC蛋白表达。结果:HE染色结果显示,与空白组相比,模型组中膀胱逼尿肌组织严重坏死,可见大量炎症细胞浸润;与模型组相比,J型针刀治疗组、治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组均有不同程度坏死组织修复情况。免疫组化检测PACAP38蛋白表达在模型组中表达量最低,针刀治疗之后,PACAP38表达量均不同程度上调;与J型针刀治疗组相比,治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组PACAP38蛋白表达均不同程度下调(P<0.05),但高于模型组(P<0.05)。Elisa检测结果显示,cAMP、PKA表达量模型组显著下调(P<0.05),J型针刀治疗组与模型组比显著上调(P<0.05),治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组比无显著差异(P>0.05)。WB结果显示:与空白组相比,模型组PKA、p-MLC蛋白表达上调;针刀治疗组表达量下调,其中PKA蛋白表达有显著性(P<0.05),p-MLC蛋白表达无显著性(P>0.05)。与J型针刀治疗组比,PKA蛋白表达量在治疗+Bupivacaine抑制剂组及治疗+H-89抑制剂组中无显著差异(P>0.05),p-MLC蛋白表达量显著下降(P<0.05)。结论:J型针刀针刺次髎穴可改善脊髓损伤后神经源性膀胱大鼠膀胱功能,其机制与J型针刀上调膀胱逼尿肌中PACAP38、cAMP、PKA表达,激活PACAP-cAMP-PKA信号通路,从而促进逼尿肌舒张有关。
基金Supported by National Natural Science Foundation of China:82274666,82205255Natural Science Foundation of Hunan Province:2022JJ30036,2022JJ40312,20221140301+1 种基金Research Project of Education Department of Hunan Province:20C1432,21B0369Discipline of Integrated Traditional Chinese and Western Medicine of Hunan Province:2020ZXYJH23。
文摘Objective:To elucidate the underlying mechanism and effect of electroacupuncture(EA)on the neurogenic bladder following suprasacral spinal cord injury(ssCI).A rat model of detrusor hyperreflexia after SsCI was established to examine the urodynamics,detrusor muscle tissue morphology,the protein and mRNA expression levels of pituitary adenylate cyclase activating peptide(PACAP)and its receptor PAC1R,and cyclic adenosine monophosphate(cAMP)content in the detrusor muscle with a focus on the PACAPcAMP signaling pathway.Method:A total of 72 female SD rats were randomized into control group and sham operation group(n=12 per group)by using a random number table.The remaining 48 rats were established into the model of detrusor hyperreflexia after SsCI.After successful modeling,these rats were randomly assigned to model,EA,and EA+PACAP6-38 groups(n=12 per group).The unsuccessful modeled rats were used for exploratory observation.For the rats in EA group,"Ciliao(BL32)""Zhongji(CV3)",and"Sanyinjiao(SP6)"were needled and stimulated by EA.The PACAP receptor antagonist PACAP6-38 was administered intraperitoneally in the EA+PACAP6-38 group before EA,and EA was applied for seven consecutive days.After treatment,the urodynamics of the rats were analyzed,and hematoxylin and eosin staining was used to examine rat bladder detrusor tissue morphology.The expressions of PACAP-38 and PAC1R were detected by immunohistochemistry and Western blot.The mRNA expression levels of PACAP-38 and PAC1R were examined by RT-qPCR,while cAMP content was detected by ELISA.Results:(1)Compared with sham operation group,it was exhibited disarray in the transitional epithelium cells of the bladder in the modeled rats.The intercellular space was significantly widened,accompanied by inflammatory cell infiltration and noticeable tissue edema.Both the bladder initial pressure and leak point pressure of the rats were higher(P<0.01),whereas the maximum cystometric capacity and bladder compliance were lower(P<0.01).The protein and mRNA expression levels of PACAP-38 and PAC1R in the detrusor muscle,together with the cAMP content,were lower(P<0.05).(2)Compared with the model rats,the EA group showed reduced inflammatory response in the detrusor muscle tissue,with decreased monocyte infiltration and less severe tissue edema.The bladder smooth muscle cells exhibited increased integrity,and there was decreased cellular tissue edema,inflammatory cell infiltration,and fibroplasia.The bladder initial pressure and leak point pressure were lower(P<0.05),while the maximum cystometric capacity and bladder compliance were higher(P<0.01).The protein and mRNA expression levels of PACAP-38 and PAC1R in the detrusor muscle,along with the cAMP content,were higher(P<0.05).(3)Compared to the EA group,the EA+PACAP6-38 group showed a less organized arrangement of muscle fibers in the detrusor muscle tissue,larger intercellular space,monocyte infltration,and considerable tissue edema.The changes in bladder initial pressure and leak point pressure were not significant(P>0.05),while the maximum cystometric capacity and bladder compliance were lower(P<0.05).The changes in the protein and mRNA expressions of PACAP-38 within the detrusor muscle were not signifcant(P>0.05),whereas the protein and mRNA expressions of PAC1R were reduced(P<0.05),and the cAMP content within the detrusor muscle was lower(P<0.05).Conclusion:EA can ameliorate the uninhibited contractile condition of the detrusor muscle in the bladder following SSCI.By mediating the PACAP-cAMP signaling pathway,it reduces the pathological damage to the detrusor muscle,thereby improving bladder function.
