Effect of acupuncture on A1R/cAMP/p-CREB signaling pathway in cau-date putamen of CFA rats / 中国病理生理杂志

AIM:To observe the effect of acupuncture on adenosine A1 receptor(A1R)in the caudate puta-men(CPu)of complete Freund's adjuvant(CFA)rats,and to explore the potential mechanism of acupuncture in treat-ment of inflammatory pain.METHODS:Sixty-four 6～8-week-old male Wistar rats were randomly divided into saline group,model group(CFA group),CFA+manual acupuncture(MA)group,CFA+solvent dimethyl sulfoxide(DMSO)group,CFA+A1R agonist 2-chloro-N6-cyclopentyladenosine(CCPA)group,CFA+A1R antagonist 8-cyclopentyl-1,3-di-propylxanthine(DPCPX)group,CFA+MA+DMSO group and CFA+MA+DPCPX group.In MA groups,on the 2nd day af-ter modeling,the rats were needled at Zusanli points on both sides,30 min at a time,once per day,for 7 d.Pain threshold of plantar thermal radiation was used to observe the pain response of the rats.The content of cyclic adenosine monophos-phate(cAMP)in the CPu was detected by ELISA.The protein expression and phosphorylation levels of protein kinase A(PKA)and cAMP response element-binding protein(CREB)were detected by Western blot.The expression of A1R in the CPu was detected by immunofluorescence staining.RESULTS:Compared with saline group,CFA modeling signifi-cantly lowered the thermal pain threshold of the rats(P<0.01).Compared with CFA group,the thermal pain threshold of the rats in CFA+MA group and CFA+CCPA group was significantly increased(P<0.05 or P<0.01).Compared with CFA+ MA+DMSO group,the thermal pain threshold of the rats in CFA+MA+DPCPX group was decreased(P<0.05).Compared with CFA group,A1R protein relative expression level and positive cells in the CPu of the rats in CFA+MA group were in-creased(P<0.05 or P<0.01).Compared with saline group,cAMP content and p-CREB protein level in the CPu of the rats in CFA+MA group were decreased(P<0.05).Compared with CFA+DMSO group,cAMP content and p-CREB pro-tein level in CFA+MA+DMSO and CFA+CCPA groups were significantly decreased(P<0.01).Compared with CFA+MA+ DMSO group,the levels of cAMP,p-PKA and p-CREB in CFA+MA+DPCPX group were significantly increased(P<0.05 or P<0.01).CONCLUSION:Acupuncture on bilateral Zusanli can relieve inflammatory pain in CFA rats,and its mech-anism may be related to A1R/cAMP/p-CREB signaling pathway.

Wenxiao Powder Alleviates Depression by Promoting Neurogenesis via BDNF/TrkB/ERK/CREB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo decipher the mechanism of Wenxiao powder in alleviating corticosterone-induced depression-like behaviors in mice. MethodMale ICR mice were randomized into normal， model， paroxetine （20 mg·kg-1）， and low- and high-dose （3.27， 6.54 g·kg-1， respectively） Wenxiao powder groups. The mice in normal and model groups received equal volume of saline. Other groups except the normal group were injected with corticosterone subcutaneously 0.5 h after gavage to induce depression. Mice were tested for depression-like behaviors after drug administration. Enzyme-linked immunosorbent assay （ELISA） was performed to measure the corticosterone content in the serum. Nissl staining was performed to observe the damage of hippocampal neurons. Immunofluorescence staining was employed to observe the expression of double cortin （DCX） in the dentate gyrus （DG） of the hippocampus. Western blot was employed to determine the expression of proteins in the brain-derived neurotrophic factor （BDNF）/tyrosine kinase receptor B （TrkB）/extracellular signal-regulated kinase （ERK）/cAMP-response element-binding protein （CREB） pathway in the hippocampus. ResultCompared with the normal group， the model group showed decreased sucrose preference rate， increased immobility time in the tail suspension test （P<0.01）， and reduced residence time in the central area of the open field and the total movement distance （P<0.05， P<0.01）. In addition， the modeling elevated the corticosterone level in the serum （P<0.01）， decreased the volume and intensified the nuclear staining of hippocampal neurons in the DG area， reduced the expression of DCX in the DG area， and down-regulated the protein levels of BDNF， phosphorylated （p）-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. Compared with the model group， low-dose Wenxiao powder improved the mouse behavivors in the sucrose preference， open field， and tail suspension tests （P<0.05， P<0.01）， and high-dose Wenxiao powder improved the behaviors in the sucrose preference and open field tests （P<0.05， P<0.01）. In addition， Wenxiao powder lowered the serum corticosterone level （P<0.01） and recovered the structure and morphology of neurons with obvious nuclei and presence of Nissl bodies in the DG area of the hippocampus. Moreover， Wenxiao powder at both doses promoted the expression of DCX in the DG area， and high-dose Wenxiao powder up-regulated the protein levels of BDNF， p-TrkB， p-ERK， and p-CREB in the hippocampus （P<0.05， P<0.01）. ConclusionWenxiao powder can alleviate corticosterone-induced depression-like behaviors and promote neurogenesis in mice possibly by activating the BDNF/TrkB/ERK/CREB signaling pathway.

Sal idroside Modulates cAMP/PKA/CREB Signaling Pathway to Inhibit Ci splatin-induced Damages of Cochlear Hair Cells and Spiral Ganglion Neurons in Mice / 听力学及言语疾病杂志

Objective To investigate the ameliorating effect of salidroside(SAL)on cisplatin(CIS)-induced damages of cochlear hair cells(CHC)and spiral ganglion neurons(SGNs)and its relationship with cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)/cAMP response element binding protein(CREB)pathway.Methods The cochlear basilar membranes of newborn C 57BL/6 mice were isolated and separated into control(C)group,CIS group,SAL group,SAL+SQ22536(cAMP inhibitor)group and SAL+H-89(PKA inhibitor)group,20 per group.Immunofluorescence staining was applied to observe the damages of CHC and SGNs.The kits were applied to detect the contents of ROS and cAMP in the basement membrane of the cochlea.Western blot was applied to detect the protein levels of PKA,p-CREB,CREB,Bcl-2,BDNF,and NF-M.Results CHC in CIS group were disorderly arranged and enlarged in size,SGNs had fragmented nuclei and lost neurites.SAL alleviated the damages of CHC and SGNs.Compared with the C group,the numbers of CHC and SGNs in the CIS group were less(P＜0.05),the contents of ROS and cAMP,and the levels of PKA,BDNF,NF-M,Bcl-2 proteins and p-CREB/CREB were higher(P＜0.05).Compared with the CIS group,the numbers of CHC and SGNs in the SAL group were higher(P＜0.05),the content of ROS was lower(P＜0.05),the content of cAMP,and the levels of PKA,BD-NF,NF-M,Bcl-2 proteins and p-CREB/CREB were higher(P＜0.05).Both SQ22536 and H-89 reversed the pro-tective effects of SAL on CHC and SGNs.Conclusion SAL may promote the expression of anti-apoptotic proteins and neuroprotective factors by activating the cAMP/PKA/CREB pathway to alleviate the damages of CHC and SGNs caused by CIS.

Mechanism of Shaoyaotang in Regulating Water Metabolism and Intestinal Epithelial Permeability in Ulcerative Colitis Through cAMP/PKA/CREB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the role of cyclic adenosine monophosphate （cAMP）/protein kinase A （PKA）/cAMP-response element binding protein （CREB） signaling pathway in water metabolism and intestinal epithelial permeability in ulcerative colitis （UC） and the intervention mechanism of Shaoyaotang based on the theory of large intestine governing fluids. MethodSixty male SD rats were divided into blank group， model group， mesalazine group （0.42 g·kg-1）， Shaoyaotang low-dose group （11.1 g·kg-1）， Shaoyaotang medium-dose group （22.2 g·kg-1） and Shaoyaotang high-dose group （44.4 g·kg-1）， with 10 in each group. The UC rat model of internal retention of dampness-heat was established by compound factors. The blank group and the model group were given normal saline （ig）. The mesalazine group was given mesalazine （ig）， and Shaoyaotang low-， medium- and high-dose groups were administrated with corresponding doses of Shaoyaotang （ig）. The treatment lasted for 14 days. The diarrhea score and fecal moisture content of rats in each group were observed. The contents of diamine oxidase （DAO） and D-lactic acid in plasma were detected by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of aquaporin （AQP）8， AQP4， ZO-1 and Occludin in colon tissues were detected by immunohistochemistry， while those of cAMP， PKA and CREB in colon tissues were determined by Western blot. ResultCompared with the normal group， the model group had elevated diarrhea score and fecal moisten content （P<0.01）， increased contents of DAO and D-lactic acid in plasma （P<0.01） and decreased protein expressions of ZO-1， Occludin， AQP8， AQP4， cAMP， PKA and CREB in colon （P<0.01）. Compared with the conditions in the model group， the contents of DAO and D-lactic acid in plasma in each administration groups were lower （P<0.01）， while the protein expressions of ZO-1， Occludin， AQP8， AQP4， cAMP， PKA and CREB in colon were higher （P<0.01）. ConclusionShaoyaotang alleviates the diarrhea in UC， probably through activating cAMP/PKA/CREB signaling pathway， up-regulating expressions of AQPs， enhancing tight junctions in intestinal epithelium and thus improving the water metabolism in colon and the intestinal mucosal permeability.

Buyang Huanwutang Treats Diabetic Peripheral Neuropathy via Mitochondrial Transport in Rats / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Buyang Huanwutang in treating diabetic peripheral neuropathy （DPN） via mitochondrial transport. MethodDiabetes in SD rats was induced by a high-carbohydrate/high-fat diet and intraperitoneal injection of streptozotocin （STZ）. The 45 diabetic rats were randomly assigned into a DPN group， an alpha-lipoic acid （60 mg·kg-1·d-1） group， and a Buyang Huanwutang （15 g·kg-1·d-1） group， with 15 rats in each group. Fifteen normal SD rats were fed with the standard diet and set as the control group. The rats were administrated with corresponding drugs by gavage for 12 weeks. The paw withdraw threshold （PWT） and motor nerve conduction velocity （MNCV） were measured at the end of medication， and the sciatic nerve and the bilateral dorsal root ganglia of L4-5 were collected. The injury model of NSC34 cells was established by treating with 50 mmol·L-1 glucose and 250 μmol·L-1 sodium palmitate. The NSC34 cells were then randomly assigned into a blank （10% blank serum） group， a DPN （10% blank serum） group， an apha-lipoic acid （10% apha-lipoic acid-containing serum） group， a Buyang Huanwutang （10% Buyang Huanwutang-containing serum） group， and a Buyang Huanwutang + Compound C （CC） （10% Buyang Huanwutang-containing serum + 10 μmol·L-1 CC） group. The cell intervention lasted for 24 h. The immunofluorescence method， immunohistochemistry， and Western blot were employed to determine the expression levels of phosphorylated adenosine monophosphate-activated protein kinase （p-AMPK）， phosphorylated cAMP-response element binding protein （p-CREB）， kinesin family member 5A （KIF5A）， and dynein cytoplasmic 1 intermediate chain 2 （DYNC1I2）. ResultCompared with the control group， the DPN group of rats showed increased fasting blood glucose （P<0.01）， decreased MNCV and PWT （P<0.01）， down-regulated expression of KIF5A， p-AMPK/AMPK， and p-CREB/CREB （P<0.01）， and up-regulated expression of DYNC1I2 （P<0.01）. Compared with the DPN group， drug intervention groups showed increased MNCV and PWT （P<0.01）， up-regulated expression of KIF5A， p-AMPK/AMPK， and p-CREB/CREB （P<0.05， P<0.01）， and down-regulated expression of DYNC1I2 （P<0.05， P<0.01）. The Buyang Huanwutang group had higher levels of MNCV and KIF5A （P<0.05） and lower level of DYNC1I2 （P<0.01） than the apha-lipoic acid group. Compared with the blank group， the DPN group of NSC34 cells showed decreased levels of KIF5A， p-AMPK/AMPK， and p-CREB/CREB （P<0.01） and increased level of DYNC1I2 （P<0.01）. The apha-lipoic acid group and Buyang Huanwutang group had higher levels of KIF5A， p-AMPK/AMPK， and p-CREB/CREB （P<0.05， P<0.01） and lower level of DYNC1I2 （P<0.01） in NSC34 cells than the DPN group. Buyang Huanwutang group had higher KIF5A level （P<0.05） in NSC34 cells than the apha-lipoic acid group. Moreover， the Buyang Huanwutang + CC group had lower levels of KIF5A， DYNC1I2， p-AMPK/AMPK， and p-CREB/CREB （P<0.01） in NSC34 cells than the Buyang Huanwutang group. ConclusionBuyang Huanwutang may regulate mitochondrial anterograde transport via the AMPK/CREB pathway to prevent and treat DPN.

Mechanism of Modified Shenqiwan in Relieving Renal Interstitial Fibrosis in Diabetic Mice Based on GSK-3β/CREB Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effects of modified Shenqiwan on renal function and fibrosis in diabetic nephropathy mice and explore the underlying mechanism based on the glycogen synthase kinase-3β （GSK-3β）/cyclic adenosine monophosphate （cAMP） response element-binding protein （CREB） signaling pathway. MethodFifty male db/db mice and 10 db/m mice were used in this study. The fifty db/db mice were randomly divided into model group， irbesartan group， and low-， medium-， and high-dose modified Shenqiwan groups. The 10 db/m mice were assigned to the normal group. The mice in the low-， medium-， and high-dose modified Shenqiwan groups were administered with modified Shenqiwan in the dosage form of suspension of Chinese medicinal granules by gavage， those in the irbesartan group were given irbesartan suspension by gavage， and those in the normal and model groups were given distilled water of equal volume by gavage. The intervention lasted for 12 weeks. The blood glucose levels， urine albumin-to-creatinine ratio （UACR）， and the protein expression levels of GSK-3β， CREB， transforming growth factor-β1 （TGF-β1）， E-cadherin， Vimentin， fibronectin （FN）， plasminogen activator inhibitor-1 （PAI-1）， and Collagen type Ⅳ （Coll Ⅳ） in the mouse kidneys were recorded before and after treatment. The extent of renal pathological damage was also observed. ResultCompared with the normal group， the model group showed significant increases in blood glucose levels， UACR levels， and the protein expression levels of GSK-3β， TGF-β1， E-cadherin， Vimentin， FN， PAI-1， and Coll Ⅳ in the kidneys （P<0.05）， decreased protein expression level of CREB （P<0.05）， and severe renal pathological damage. Compared with the model group， the low-， medium-， and high-dose modified Shenqiwan groups and the irbesartan group showed varying degrees of decreases in blood glucose levels， UACR levels， and the protein expression levels of GSK-3β， TGF-β1， E-cadherin， Vimentin， FN， PAI-1， and Coll Ⅳ in the kidneys （P<0.05）， increased expression level of CREB protein （P<0.05）， and improved renal pathological damage. ConclusionModified Shenqiwan can effectively reduce blood glucose levels， improve renal function， and alleviate fibrosis， and the mechanism of action is related to the inhibition of the GSK-3β/CREB signaling pathway.

Mechanism of miR-26a-5p/cAMP response element binding protein 1 molecular axis regulating osteogenic differentiation of adipose-derived mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1).@*METHODS@#The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture.@*RESULTS@#The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05).@*CONCLUSION@#Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.

Protective effects of the salt-induced kinase inhibitor HG-9-91-01 on sepsis-associated cognitive dysfunction in mice and the underlying mechanisms / 中南大学学报(医学版)

Objective:Sepsis-associated cognitive dysfunction is a common complication in patients with sepsis and lack of effective treatment.Its pathological mechanisms remain unclear.Salt-induced kinase(SIK)is an important molecule in the regulation of metabolism,immunity,and inflammatory response.It is associated with the development of many neurological diseases.This study aims to investigate the expression of SIK in the hippocampus of septic mice,and to evaluate the role and mechanism of the SIK inhibitor HG-9-91-01 in sepsis-associated cognitive dysfunction. Methods:Firstly,C57BL/6 mice were randomly divided into a control group(Con group)and a sepsis model group[lipopolysaccharide(LPS)group].The model group was injected intraperitoneally with LPS at a dose of 8 mg/kg and the Con group was injected with an equal volume of normal saline.Hippocampal tissues were harvested at 1,3,and 6 days after injection and the expressions of SIK1,SIK2,and SIK3 were detected by real-time fluorescence quantitative PCR(qPCR)and Western blotting.Secondly,C57BL/6 mice were randomly divided into a Con group,a LPS group,and a SIK inhibitor group(HG group).The LPS and HG groups were injected with LPS to establish a sepsis model;in the HG group,HG-9-91-01(10 mg/kg)was injected intraperitoneally at 3-6 days after LPS injection,and the LPS group was injected with the same volume of vehicle.Cognitive function was assessed at 7-11 days after LPS injection using the Morris water maze(MWM).Hippocampal tissues were harvested after the behavioral tests,and the mRNA levels of inflammatory factors and microglial markers were assessed by qPCR.The protein levels of inducible nitric oxide synthase(iNOS),CD68,ionized calcium binding adaptor molecule 1(Iba-1),N-methyl-D-aspartate(NMDA)receptor(NR)subunit,cAMP response element-binding protein(CREB)-regulated transcription coactivator 1(CRTC1),and insulin-like growth factor 1(IGF-1)were detected by Western blotting.Immunohistochemistry(IHC)was used to detect the expression of Iba-1 positive cells in the CA1,CA3 and dentate gyrus(DG)of the hippocampus,followed by Sholl analysis. Results:Compared with the Con group,the mRNA and protein levels of SIK1,SIK2,and SIK3 in the hippocampus were increased in the LPS group(all P<0.05).Compared with the Con group,mice in the LPS group had a significantly longer escape latency,a lower percentage of target quadrant dwell time and a reduced locomotor speed(all P<0.05);the HG group had a decreased escape latency and an increased percentage of time spent in the target quadrant in comparison with the LPS group(both P<0.05).The mRNA levels of inflammatory factors[tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),interleukin-6(IL-6)],and the M1-type microglial markers iNOS and CD68 in the hippocampus of the LPS group were increased in comparison with the Con group,while the M2-type microglial markers CD206 and arginase-1(Arg-1)were decreased.Compared with the LPS group,the mRNA levels of TNF-α,IL-1β,IL-6,and iNOS were downregulated,while the levels of CD206 and Arg-1 were upregulated in the HG group(all P<0.05).The protein levels of iNOS,CD68,and Iba-1 in the hippocampus of the LPS group were increased in comparison with the Con group,but they were downregulated in the HG group in comparison with the LPS group(all P<0.05).The number of Iba-1 positive cells in CA1,CA3,and DG of the hippocampus was increased in the LPS group in comparison with the Con group,but they were decreased in the HG group in comparison with the LPS group(all P<0.05).Sholl analysis showed that the number of intersections at all radii between 8-38 μm from the microglial soma was decreased in the LPS group in comparison with the Con group(all P<0.05).Compared with the LPS group,the number of intersections at all radii between 14-20 μm was significantly increased in the HG group(all P<0.05).The protein levels of NR subunit NR1,NR2A,NR2B,and IGF-1 were downregulated in the hippocampus of the LPS group in comparison with the Con group,while the expression of phosphorylated CRTC1(p-CRTC1)was increased.Compared with the LPS group,the levels of NR1,NR2A,NR2B,and IGF-1 were upregulated,while p-CRTC1 was downregulated in the HG group(all P<0.05). Conclusion:SIK expression is upregulated in the hippocampus of septic mice.The SIK inhibitor HG-9-91-01 ameliorates sepsis-associated cognitive dysfunction in mice,and the mechanism may involve in the activation of the CRTC1/IGF-1 pathway,inhibition of neuroinflammation,and enhancement of synaptic plasticity.

Effects of enriched environment on anxiety- and depressive-like behavior and synaptic plasticity in neuropathic pain rats / 中华行为医学与脑科学杂志

Objective:To explore the effect of enriched environment on pain sensitivity, anxiety- and depressive-like behavior in selective nerve injury(SNI) rats model and its potential mechanism.Methods:A total of 36 male clean grade SD rats aged 6-8 weeks were randomly divided into three groups( n=12 in each group): sham operation+ standard environment group (sham group), SNI+ standard environment group (standard environment group), SNI+ enriched environment group (enriched environment group). The rat model of neuropathic pain was established by SNI.The rats in the enriched enviroment group were placed in an enriched enviroment 7 days before operation until 21 days after operation.The paw withdraw threshold(PWT) and paw withdraw latency (PWL) were performed to assess hyperalgesia.The open field test, elevated plus maze test, novelty suppressed feeding test and forced swimming test were used to assess anxiety and depression like behavior.The expressions of cAMP response element binding protein (CREB), p-CREB, brain-derived neurotrophic factor (BDNF), postsynaptic density-95 (PSD-95) and neuroligin 2 (NLGN2) were detected by Western blot.The expression of CREB and BDNF in contralateral ACC were measured by immunofluorescence.GraphPad prism 8.0 and SPSS 23.0 were used for data analysis.One way ANOVA was used for inter group comparison, repeated measurement ANOVA was used to analyze PWT and PWL results, and Tukey test was used for pairwise comparison. Results:(1) In PWT and PWL experiments, the interaction effect between group and time, group main effect and time main effect of PWT were significant ( F=13.4, 39.6, 369.6, all P<0.05), and the interaction effect between group and time, group main effect and time main effect of PWL were significant ( F=3.8, 10.3, 58.8, all P<0.05). Compared with sham group, PWT((8.0±3.5) g, (2.4±1.4) g, (2.3±1.1) g, (2.2±1.6) g, (1.6±0.5) g) and PWL((8.6±1.3) s, (7.3±1.5) s, (7.9±1.0) s, (6.6±1.1) s, (7.7±1.4) s) in standard environment group decreased at each time point (all P<0.05). (2) Compared with sham group, the number of entrying into the central area (1.3±1.7), the time of entrying into the central area((1.6±1.3) s), the proportion of entering open arms ((8.0±7.8) %) and the proportion of time in the open arms ((1.3±1.2) %) all significantly decreased in standard environment group ( t=4.585, 5.423, 4.682, 5.202, all P<0.05). The eating latency ((365.2±94.4) s) and immobility time ((127.6±24.3) s) dramatically increased ( t=6.008, 14.290, both P<0.05). The number and time of entrying into central area of enriched environment group were both higher than those of standard environment group(both P<0.05), while the eating latency and immobility time of enriched environment group were both lower than those of standard environment group(both P<0.05). (3) Compared with sham group(CREB: (1.6±0.2), (0.8±0.5); BDNF: (0.8±0.5), (1.0±0.4)), the expression of CREB ((1.8±0.1), (1.5±0.2)), BDNF ((0.9±0.6), (1.4±0.3)) in spinal cord and ACC of standard environment group increased (spinal: t=3.283, 4.989; ACC: t=5.502, 4.257, all P<0.05). The expression of PSD-95 ((1.6±0.2), (1.0±0.2) and NLGN2 ((1.5±0.5), (1.1±0.2)) also increased in ACC of standard enviroment group ( t=4.257, 2.214, both P<0.05). Compared with standard environment group, the expression of CREB (1.3±0.3), BDNF (0.7±0.4), PSD-95(1.0±0.3) and NLGN2(1.1±0.4) in spinal cord of enriched environment group decreased ( t=5.007, 2.166, 2.358, 2.322, all P<0.05). The expression of PSD-95(1.2±0.3) and NLGN2(1.1±0.2) also decreased in ACC of enriched environment group ( t=2.674, 2.944, both P<0.05). However, the expression of p-CREB (1.7±0.6) and BDNF (2.4±0.2) increased in ACC ( t=4.180, 7.610, P<0.05). Conclusion:Enriched environment can improve neuropathic pain and anxiety- and depressive-like behavior in SNI rats, which may be related to the change of synaptic plasticity in spinal cord and ACC.

Total Flavones of Spatholobi Caulis Regulate Hippocampal Neuroplasticity in Depressed Rats Through CREB/BDNF Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect and mechanism of total flavones of Spatholobi Caulis （TFSC） against depression in rats. MethodThe fifty KM mice were randomly divided into the normal group and high-， medium-， and low-dose （1， 0.5， 0.25 g·kg-1） TFSC groups and gavaged with the corresponding drugs for 12 successive days. One hour after the last administration， the immobility time in forced swimming test and tail suspension test was recorded. The SD rats were randomly divided into the normal group， model group， fluoxetine （5 mg·kg-1） group， and high- and low-dose （1， 0.25 g·kg-1） TFSC groups. Following the exposure of rats to two different kinds of stimuli daily for inducing chronic unpredictable stress， they were administered with the corresponding drugs for 21 d. After the experiment， the levels of serum neurotransmitters and inflammatory factors in rats were detected by enzyme-linked immunosorbent assay （ELISA）. The changes in hippocampal neurons of rats were observed by hematoxylin-eosin （HE） and Nissl staining. The mRNA expression levels of nuclear factor-κB （NF-κB） and tumor necrosis factor-α （TNF-α） in the hippocampus of rats were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， and the protein expression levels of cAMP-response element binding protein （CREB）， phosphorylated CREB （p-CREB）， and brain-derived neurotrophic factor （BDNF） in hippocampal tissues by Western blot. ResultCompared with the normal group， TFSC significantly shortened the immobility time of mice in tail suspension and swimming tests （P<0.05）. Compared with the normal group， the model group exhibited reduced sucrose intake and wilderness activity （P<0.01）， decreased 5-HT， DA， NE （P<0.05， P<0.01）， MAO， IL-6， TNF-α （P<0.05， P<0.01）， damaged neurons， increased mRNA levels of TNF-α and NF-κB （P<0.01）， and down-regulated BDNF and CREB protein expression （P<0.05）. Compared with the model group， TFSC significantly enhanced sucrose intake and wilderness activity of rats （P<0.05）， increased the serum 5-HT， DA and NE （P<0.05， P<0.01）， and decreased the serum MAO， IL-6， and TNF-α （P<0.05， P<0.01） as well as NF-κB and TNF-α mRNA expression （P<0.01）， up-regulated the protein expression levels of BDNF and CREB （P<0.01）， and improved the pathological symptoms of hippocampus. ConclusionTFSC improved the hippocampal neurons of rats via CREB/BDNF signaling pathway and reduced depressive pathological damage， thus relieving depression.

Role of microRNA-132 and Mecp2 in methamphetamine dependence / 中国药理学通报

Aim To explore the roles of miRNA-132 and its related proteins(Mecp2, CREB)in the mechanism of methamphetamine(MA)-induced neurotoxicity and dependence.Methods The rats were intraperitioneally injected(ip)with MA(10 mg·kg-1·d-1)to establish methamphetamine dependence model with different dependent time courses of 1 week, 2 weeks, and 4 weeks respectively.The miRNA-132 and Mecp2 mRNA were detected by RT-qPCR, and the Mecp2, p-Mecp2, CREB and p-CREB proteins were detected by Western blot in the tissues of frontal cortex and hippocampus.Results In the frontal cortex, the miRNA-132 and Mecp2 mRNA were up-regulated in MA-dependent groups(P<0.05 and P<0.01), while the Mecp2 protein were down-regulated(P<0.01).MA could promote the phosphorylation of Mecp2 protein in the frontal cortex(P<0.01).In hippocampus, the miRNA-132 was down-regulated in the MA-dependent groups, but Mecp2 mRNA was up-regulated(P<0.05).Mecp2 protein increased in MA-dependent 1 week group(P<0.05), and then recovered with the prolonged time of MA dependence, then decreased in MA-dependent 4 weeks groups(P<0.05)in hippocampus.The phosphorylation level of Mecp2 was significantly decreased in the 1 week group(P<0.01), and then increased in the 2 weeks group(P<0.01)in hippocampus.Conclusions MA could induce an abnormal expression of miRNA-132 in the frontal cortex and hippocampus, and miRNA-132 might inhibit the translation of Mecp2 mRNA and induce the decrease expression of Mecp2 protein in the frontal cortex.But in hippocampus, miRNA-132 does not show the correlation with the Mecp2 expression trend of the frontal cortex.And miRNA-132 regulation does not depend on the expression of Mecp2 in hippocampus.

Effects of baicalin on depressive behavior and ERK/CREB protein in hippocampus of depression model mice / 中华行为医学与脑科学杂志

Objective:To explore the regulation effects of baicalin on the behavior as well as extracellular regulated protein kinase(ERK)and cAMP-response element binding protein(CREB) in chronic unpredictable mild stimulus(CUMS) model mice.Methods:Thirty ICR mice were randomly assigned to control(CON) group, model(CUMS) group, fluoxetine(FLU) group, baicalin high-dose(BA-H) group and baicalin low-dose(BA-L) group with 6 mice in each group.In addition to the CON group, the mice in the other four groups were modeled by CUMS method.The modeling was carried out for 42 days, and intragastric administration was carried out according to groups from the 21st day to the completion of modeling.After administration, the depression like behavior of mice was measured by sugar water preference test and water maze test.Western blot (WB) and reverse transcription polymerase chain reaction (RT-PCR) were used to detect the protein level and mRNA level of ERK and CREB in mouse hippocampus respectively.SPSS 21.0 was used for statistical analysis.After normal test and variance homogeneity test, one-way ANOVA was used for multi group comparison, and Tukey test was used for pairwise comparison.Results:Results from the sugar preference experiment showed that compared with CON group, the sugar preference rate of CUMS group was decreased ((82.88±2.00)%, (64.49±1.24)%, t=19.11, P<0.05). Compared with CUMS group, sugar preference rate in FLU group ((81.90±1.19) %), BA-H group (77.86±2.51)%) and BA-L group ((67.98±2.56)%) increased ( t=24.83, 11.68, 3.00, all P<0.05). The results of water maze test showed that compared with CON group, the number of crossing platform ((6.33±0.82), (1.83±0.75), t=9.93, P<0.05) and the target quadrant residence time ((46.83±4.78)s, (24.25±6.12)s, t=7.13, P<0.05) of mice in CUMS group were decreased, but the the escape latency was prolonged ((14.88±3.00) s, (70.70±4.77) s, t=24.26, P<0.05). Compared with CUMS group, the number of crossing platform ((5.00±0.89)times, (5.17±0.75)times and (3.33±0.82) times, t=6.64, 7.67, 3.31, all P<0.05), and the residence time in the target quadrant ((36.80±2.66) s, (36.82±5.62) s, (33.28±3.56) s, t=4.61, 3.71, 3.13, all P<0.05) in FLU group, BA-H group and BA-L group increased, but the escape latencies were shortened ((23.37±4.86) s, (34.83±4.72) s, (62.15±5.30) s, t=17.02, 13.10, 2.94, all P<0.05). WB results showed that compared with CON group, the expression of ERK protein ((1.00±0.15), (0.36±0.10), t= 6.26, P<0.05) and CREB protein((1.00±0.12), (0.29±0.03), t=10.32, P<0.05) in hippocampus of mice in CUMS group decreased.Compared with CUMS group, ERK protein in hippocampus of mice in FLU, BA-H and BA-L groups increased ((0.87±0.05), (0.77±0.08), (0.67±0.03), t=8.25, 5.7, 5.39, all P<0.05), and CREB protein in FLU, BA-H and BA-L groups were also increased ((0.90±0.12), (0.84±0.14), (0.62±0.04), t=8.94, 6.59, 12.25, all P<0.05). qPCR results showed that compared with CON group, ERK mRNA ((1.00±0.03), (0.41±0.10), t=9.78, P<0.05) and CREB mRNA ((1.00±0.08), (0.61±0.12), t=4.62, P<0.05) were decreased in CUMS group.Compared with CUMS group, ERK mRNA in hippocampus of mice in FLU, BA-H and BA-L groups were increased ((0.71±0.08), (0.69±0.03), (0.59±0.04), t=4.15, 4.65, 2.84, all P<0.05), CREB mRNA in FLU group and BA-H group were increased ((0.87±0.08), (0.86±0.07), t=3.14, 3.19, all P<0.05). Conclusion:BA can improve the depression-like behavior of CUMS model mice.The mechanism of action may be related to the regulation of ERK and CREB proteins.

Effect of Jianpi Bufei Prescription on cAMP/PKA/CREB Signaling Pathway in Juvenile Asthma Rats / 中国实验方剂学杂志

Objective:To investigate the effect of Jianpi Bufei prescription （JPBFP） on airway inflammation， airway hyperresponsiveness （AHR）， and cyclic adenosine monophosphate （cAMP） signaling pathway activity in ovalbumin （OVA）-sensitized and challenged juvenile asthma rats. Method:Seventy-five male SD rats were randomly divided into a blank group （<italic>n</italic>=15） and an experimental group （<italic>n</italic>=60）. The rats in the experimental group were sensitized by aluminum hydroxide gel containing 0.2% OVA and stimulated by aerosol inhalation of normal saline containing 1% OVA to induce an asthma model， followed by assignment into the following groups： a model group （<italic>n</italic>=15）， a JPBFP group （<italic>n</italic>=15， 8.37 g·kg^-1·d^-1）， an aminophylline group （<italic>n</italic>=15， 40 mg·kg^-1·d^-1）， and a dexamethasone group （<italic>n</italic>=15， 0.1 mg·kg^-1·d^-1）. AHR was detected by the pulmonary function analyzer， changes in inflammatory cells by white blood cell （WBC） count and differential blood count in bronchoalveolar lavage fluid （BALF）， and pathological changes of lung tissues by hematoxylin-eosin （HE）， Masson， and periodic acid-schiff （PAS） staining. The interleukin （IL）-4， IL-5， IL-13， interferon （IFN）-<italic>γ</italic>， and tumor necrosis factor （TNF）-<italic>α</italic> levels in serum and the cAMP level in plasma were tested by the enzyme-linked immunosorbent assay （ELISA）. Protein kinase A （PKA） expression in lung tissues was detected by immunohistochemistry. The cAMP-response element-binding protein （CREB） mRNA and protein expression in lung tissues was detected by the real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. Result:Compared with the blank group， the model group showed increased lung resistance， decreased pulmonary compliance （<italic>P</italic><0.05）， elevated WBC count and proportion of eosinophils in BALF （<italic>P</italic><0.05）， up-regulated levels of IL-4， IL-5， IL-13， and TNF-<italic>α</italic> in peripheral blood， declining IFN-<italic>γ</italic> level （<italic>P</italic><0.01）， severe pathological changes of lung tissues， dwindled cAMP， and down-regulated PKA and CREB expression （<italic>P</italic><0.01）. Compared with the model group， JPBFP inhibited AHR， reduced WBC count and proportion of eosinophils in BALF and lung resistance （<italic>P</italic><0.05）， improved pathological changes of lung tissues， increased pulmonary compliance， and up-regulated cAMP in serum and PKA and CREB expression in lung tissues （<italic>P</italic><0.01）. Conclusion:JPBFP can improve AHR， inhibit airway inflammation， and alleviate lung injury in asthma rats. Its mechanism may be related to the up-regulation of the activity of the cAMP/PKA/CREB signaling pathway.

Da Chaihutang Protects Liver Mitochondrial Function of Nutritionally Obese Rats via CREB/PGC-1α Pathway / 中国实验方剂学杂志

Objective:To observe the effects of Da Chaihutang on Cyclic adenosine monophosphate （cAMP）-response element binding protein （CREB）/peroxisome proliferator-activated receptor-gamma coactivator-1 alpha （PGC-1<italic>α</italic>） pathway in nutritionally obese rats and the protective mechanism on liver mitochondria. Method:A total of 120 8-week-old male SD rats were randomly divided into a control group （<italic>n</italic>=20） and an experimental group （<italic>n</italic>=100）. The rats in the control group were fed on a normal diet， while those in the experimental group were administered with a high-fat feed. Successfully modeled rats were randomly divided into a model group， a positive drug （metformin） group， and low-， medium- and high-dose Da Chaihutang groups （4.25， 8.5， and 17 g∙kg^-1， respectively）， with 20 rats in each group. After treatment with Da Chaihutang， the body weight， Lee's index， liver mitochondrial membrane potential and mitochondrial ultrastructure， PGC-1<italic>α </italic>expression and CREB phosphorylation of each group were measured and compared. Result:Compared with the control group， the model group showed increased body weight and Lee's index （<italic>P</italic><0.01）， whereas decreased mitochondrial membrane potential， PGC-1<italic>α</italic> expression， and CREB phosphorylation level （<italic>P</italic><0.01）. As compared with the model group， Da Chaihutang significantly reduced the body weight and Lee's index of obese rats （<italic>P</italic><0.05， <italic>P</italic><0.01）， enhanced liver mitochondrial membrane potential （<italic>P</italic><0.05， <italic>P</italic><0.01） to protect the integrity of mitochondrial structure， up-regulated PGC-1<italic>α</italic> expression and promoted CREB phosphorylation （<italic>P</italic><0.05， <italic>P</italic><0.01）. Conclusion:Da Chaihutang protects the structure and function of mitochondria and inhibits weight gain in obese rats by activating the CREB/PGC-1<italic>α</italic> pathway.

Effect of Wendantang-containing Serum on CREB Gene Silencing Hippocampal Neuron Apoptosis and BDNF/TrkB/CREB Signaling Pathway / 中国实验方剂学杂志

Objective:To investigate the effect of Wendantang on cyclic adenosine monophosphate （cAMP）-response element binding protein（CREB） gene silencing hippocampal cell activity， apoptosis and signal pathway of brain-derived neurotrophic factor/protomyosin related receptor kinase B/adenosine cyclophosphate effector binding protein （BDNF/TrkB/CREB）. Method:Wendantang-containing serum was prepared. Animal grouping： SD male rats were randomly divided into high， medium， low-dose groups， clozapine group and normal saline group， with 10 rats in each group， while 15 rats for the normal group. Dosage： 20 mL·kg-1 normal saline was given to normal group N， clozapine 0.02 g·kg-1 was given to dozapine group X， while high， medium and low-dose Wendantang groups were respectively given the same amount of Wendantang concentrated crude drug， with concentrations of 2， 1 and 0.5 g·mL-1 respectively once a day for 8 days continuously， and then blood was taken from femoral artery， and centrifuged for 15 min at 5 000 r·min-1. Supernatant was taken， inactivated， stored at -80 ℃ for standby. The CREB gene silenced hippocampal neuron cell line was constructed through transfection of liposomes into hippocampal cells， and Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to verify the effect of small interfering RNA （siRNA） transcription. The mRNA expressions of BDNF， TrkB， CREB and CaMKⅡ in normal hippocampal cells and CREB gene silenced hippocampal cells were measured. Result:Compared with normal group， the apoptosis of the normal gene silencing group was significantly increased （P<0.01）， compared with the normal gene silencing group， the apoptosis of each group was significantly reduced （P<0.01）. As for the mRNA expressions of BDNF， TrkB， CREB and CaMKⅡ， compared with the normal group， the mRNA expression of CREB， BDNF in the normal gene silencing group was significantly decreased （P<0.01）. Compared with the normal gene silencing group， the mRNA expression of BDNF in each administration group was highly increased （P<0.01）， but with no statistically significant difference between TrkB and CaMKⅡ groups. Conclusion:The Wendantang-containing serum could improve the mRNA expression of BDNF， protect hippocampal neurons and prevent cognitive impairment of schizophrenia by regulating BDNF/TrkB/CREB signal pathway.

Effect of electroacupuncture on expression of CREB and its ability to bind to synaptic proteins in amygdala and hippocampus of rats with post-traumatic stress disorder / 针刺研究

OBJECTIVE: To observe the effect of electroacupuncture (EA) on the expression of cAMP-response element binding protein (CREB, a key protein for BDNF-TrkB signaling) and it's blinding ability to synaptic key protein in the amygdala and hippocampus of rats with post-traumatic stress disorder (PTSD), so as to lay a foundation for further study of the interaction mechanism between BDNF-TrkB signaling and synaptic plasticity. METHODS: Twenty-four male SD rats were randomly divided into blank, model and electroacupuncture (EA) groups, with 8 rats in each group. The PTSD model was established by psychological stress (bondage) and physiological stress (forced swimming and anesthesia). After modeling, EA (2 Hz/100 Hz, 1 mA) was applied to "Baihui"(GV20) "Shenting"(GB24) and bilateral "Shenshu"(BL23) for 20 min, once daily for 21 days. The behavioral changes (spontaneous locomotor within 30 min and contextual fear conditioning tests in 7 days) were detected by using a spontaneous locomotor detection box, and a conditioned fear response test chamber, respectively. The expression of CREB was detected by immunohistochemistry and Western blot, separately. The binding abilities of CREB to synaptic proteins (post synaptic density 95 [PSD95], synaptophysin [SYN] and growth-associated protein 43 [GAP43]) were verified by chromatin-immunoprecipitation (CHIP) technique. RESULTS: After modeling, the spontaneous locomotor distance, the expression levels of CREB and the binding ability of CREB to PSD95 protein in the amygdala and hippocampus were significantly decreased (P0.05). CONCLUSION: EA can improve the motor activity in PTSD rats, which may be associated with its effect in increasing the binding ability of CREB to the synaptic key protein PSD95 to regulate the interaction between the synaptic plasticity and BDNF-TrkB signaling pathway of the amygdala and hippocampus.

Taurochenodeoxycholic acid mediates cAMP-PKA-CREB signaling pathway / 中国天然药物

Taurochenodeoxycholic acid (TCDCA) is one of the main effective components of bile acid, playing critical roles in apoptosis and immune responses through the TGR5 receptor. In this study, we reveal the interaction between TCDCA and TGR5 receptor in TGR5-knockdown H1299 cells and the regulation of inflammation via the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element binding (CREB) signal pathway in NR8383 macrophages. In TGR5-knockdown H1299 cells, TCDCA significantly activated cAMP level via TGR5 receptor, indicating TCDCA can bind to TGR5; in NR8383 macrophages TCDCA increased cAMP content compared to treatment with the adenylate cyclase (AC) inhibitor SQ22536. Moreover, activated cAMP can significantly enhance gene expression and protein levels of its downstream proteins PKA and CREB compared with groups of inhibitors. Additionally, TCDCA decreased tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8 and IL-12 through nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activity. PKA and CREB are primary regulators of anti-inflammatory and immune response. Our results thus demonstrate TCDCA plays an essential anti-inflammatory role via the signaling pathway of cAMP-PKA-CREB induced by TGR5 receptor.

Effect of electrical stimulation at auricular points combined with sound masking on the expression of CREB, BDNF and TrkB in the auditory cortex of tinnitus rats / 中国针灸

OBJECTIVE@#To explore the effect of electrical stimulation at auricular points (EAS) combined with sound masking on the expression of cAMP-response element binding protein (CREB), brain-derived neurotrophic factor (BDNF) and tyrosine receptor kinase B (TrkB) in the auditory cortex of tinnitus rats.@*METHODS@#A total of 27 adult male SD rats were randomly divided into a control group, a model group and an EAS group. The rats in the model group and the EAS group were intervened with intraperitoneal injection of sodium salicylate to induce tinnitus model, while the rats in the control group were intervened with injection of 0.9% NaCl solution. After the model was successfully established, the rats in the EAS group were treated with electrical stimulation at "Shenmen" (TF) and "Yidan" (CO), combined with sound masking; the treatment was given once a day for 15 days. The gap prepulse inhibition of acoustic startle (GPIAS) and prepulse inhibition (PPI) testing were performed using the acoustic startle reflex starter package for rats. The expression of BDNF, TrkB, CREB and p-CREB in the auditory cortex of each group were measured with Western Blot analysis.@*RESULTS@#① Compared with the control group, the GPIAS values in 12 kHz, 16 kHz, 20 kHz and 28 kHz were significantly decreased in the model group (all 0.05).@*CONCLUSION@#EAS could improve the GPIAS values of high-frequency background sound in tinnitus rats, which may be related with the upregulation of the BDNF/TrkB/CREB signaling pathway in the auditory cortex, leading to the reversion of the maladaptive plasticity.

Heat shock protein 70 increases cell proliferation, neuroblast differentiation, and the phosphorylation of CREB in the hippocampus / 한국실험동물학회지

In the present study, we investigated the effects of heat shock protein 70 (HSP70) on novel object recognition, cell proliferation, and neuroblast differentiation in the hippocampus. To facilitate penetration into the blood–brain barrier and neuronal plasma membrane, we created a Tat-HSP70 fusion protein. Eight-week-old mice received intraperitoneal injections of vehicle (10% glycerol), control-HSP70, or Tat-HSP70 protein once a day for 21 days. To elucidate the delivery efficiency of HSP70 into the hippocampus, western blot analysis for polyhistidine was conducted. Polyhistidine protein levels were significantly increased in control-HSP70- and Tat-HSP70-treated groups compared to the control or vehicle-treated group. However, polyhistidine protein levels were significantly higher in the Tat-HSP70-treated group compared to that in the control-HSP70-treated group. In addition, immunohistochemical study for HSP70 showed direct evidences for induction of HSP70 immunoreactivity in the control-HSP70- and Tat-HSP70-treated groups. Administration of Tat-HSP70 increased the novel object recognition memory compared to untreated mice or mice treated with the vehicle. In addition, the administration of Tat-HSP70 significantly increased the populations of proliferating cells and differentiated neuroblasts in the dentate gyrus compared to those in the control or vehicle-treated group based on the Ki67 and doublecortin (DCX) immunostaining. Furthermore, the phosphorylation of cAMP response element-binding protein (pCREB) was significantly enhanced in the dentate gyrus of the Tat-HSP70-treated group compared to that in the control or vehicle-treated group. Western blot study also demonstrated the increases of DCX and pCREB protein levels in the Tat-HSP70-treated group compared to that in the control or vehicle-treated group. In contrast, administration of control-HSP70 moderately increased the novel object recognition memory, cell proliferation, and neuroblast differentiation in the dentate gyrus compared to that in the control or vehicle-treated group. These results suggest that Tat-HSP70 promoted hippocampal functions by increasing the pCREB in the hippocampus.

High frequency repeated transcranial magnetic stimulation improves learning and memory of global cerebral ischemia rats and its mechanism / 中华神经科杂志

Objective To study the effect of high frequency repeated transcranial magnetic stimulation (rTMS) on learning and memory in rats with global cerebral ischemia and to investigate its mechanism.Methods Thirty-five male Sprague-Dawley rats (8-10 weeks old) were randomly divided into sham operation group (n=8),model group (n=9),sham-rTMS (s-rTMS) group (n=9) and rTMS group (n=9).The global cerebral ischemia model was established by modified four-vessel occlusion method.The rTMS group received 10 Hz rTMS stimulation for two weeks,whereas the s-rTMS group received sham stimulation.Morris water maze test was used to detect the spatial learning ability,multi-channel recording technique was used to detect the local field potentials in the hippocampus CA1 region of theta and gamma oscillation,and immunohistochemical staining and Western blotting were used to detect the expression of protein kinase A (PKA) and phosphorylated cyclic adenosine monophosphate response element binding protein (p-CREB) of hippocampus.Results The average escape latency in the model group was longer than that in the sham operation group ((35.16±0.80) s vs (16.57±0.74) s,k=3.723,P=0.013),the spanning platform times and the original platform quadrant swimming time in the model group were shorter than that in the sham operation group (1.14±0.42 vs 4.46±0.23,k=3.185,P=0.042;(14.46±0.73) s vs (29.31±0.42) s,k=3.027,P=0.047).Compared with the sham operation group,the mean power spectral density of theta and gamma reduced ((-68.48±2.61) Hz vs (-59.38±2.25) Hz,k=2.958,P=0.048;(-82.23±4.60) Hz vs (-70.50±4.25) Hz,k=3.729,P=0.021),and the expression of PKA and p-CREB protein decreased in the model group (7 184.26±975.12 vs 25 137.35±1 010.62,k=3.588,P=0.027;1 803.73±336.18 vs 20 175.25±727.23,k=2.912,P=0.049).The average escape latency in the rTMS group was shorter than that in the model group ((24.69± 1.01) s vs (35.16±0.80) s,k=4.082,P=0.034),and the spanning platform times and the original platform quadrant swimming time in the rTMS group was longer than that in the model group (2.42±0.31 vs 1.14±0.42,k=3.296,P=0.039;(23.07±0.67) s vs (14.46±0.73) s,k=4.323,P=0.012).Compared with the rTMS group,the power spectral density of theta and gamma reduced ((-63.81±3.12) Hz vs (-68.48±2.61) Hz,k=3.582,P=0.015;(-75.80±4.58) Hz vs (-82.23±4.60) Hz,k=4.051,P=0.026),and the expression of PKA and p-CREB protein decreased in the model group (13 065.32±1 045.18 vs 7 184.26±975.12,k=3.923,P=0.031;11 032.83±562.86 vs 18 03.73±336.18,k=3.178,P=0.038).Conclusion High frequency rTMS could improve learning and memory of global cerebral ischemia rats,the mechanism of which might be that rTMS enhance the hippocampal theta and gamma oscillations and increase the expression of PKA and p-CREB protein in the hippocampus,thus increasing the hippocampus synaptic plasticity.