Electro-acupuncture modulated miR-214 expression to prevent chondrocyte apoptosis and reduce pain by targeting BAX and TRPV4 in osteoarthritis rats

Osteoarthritis (OA) is a highly prevalent joint disorder characterized by progressive degeneration of articular cartilage, subchondral bone remodeling, osteophyte formation, synovial inflammation, and meniscal damage. Although the etiology of OA is multifactorial, pro-inflammatory processes appear to play a key role in disease pathogenesis. Previous studies indicate that electroacupuncture (EA) exerts chondroprotective, anti-inflammatory, and analgesic effects in preclinical models of OA, but the mechanisms underlying these potential therapeutic benefits remain incompletely defined. This study aimed to investigate the effects of EA on OA development in a rat model, as well as to explore associated molecular mechanisms modulated by EA treatment. Forty rats were divided into OA, EA, antagomiR-214, and control groups. Following intra-articular injection of monosodium iodoacetate to induce OA, EA and antagomiR-214 groups received daily EA stimulation at acupoints around the knee joint for 21 days. Functional pain behaviors and chondrocyte apoptosis were assessed as outcome measures. The expression of microRNA-214 (miR-214) and its downstream targets involved in apoptosis and nociception, BAX and TRPV4, were examined. Results demonstrated that EA treatment upregulated miR-214 expression in OA knee cartilage. By suppressing pro-apoptotic BAX and pro-nociceptive TRPV4, this EA-induced miR-214 upregulation ameliorated articular pain and prevented chondrocyte apoptosis. These findings suggested that miR-214 plays a key role mediating EA's therapeutic effects in OA pathophysiology, and represents a promising OA treatment target for modulation by acupuncture.

Anti-nociceptive effect and mechanism of madecassic acid / 中国药科大学学报

@#Abstract: To date, the investigation of the functional composition of Centella asiatica (L.) Urban has been mainly focused on the triterpenoid saponins, with little research on the other compositions. The acetic acid-induced writhing, Eddy's hot plate and formalin tests were employed to investigate the anti-nociceptive effects of madecassic acid (MA). The experiment was divided into normal control group, acetylsalicylic acid (ASA) group, and the MA groups of low (10 mg/kg), medium (20 mg/kg) and high (40 mg/kg) dosage. Meanwhile, the anti-nociceptive effect of MA on the acetic acid and formalin-induced nociceptive models in the absence and presence of NAL (naloxone hydrochloride) was evaluated. To have an insight into the anti-nociceptive mechanisms of MA, the capsaicin- and glutamate-induced paw licking tests were also employed to evaluate the involvement of the vanilloid and glutamatergic systems, respectively. Results showed that MA exhibited good anti-nociceptive activity in the acetic acid-induced writhing test and the second phase of formalin test; the anti-nociceptive effect of MA in both the acetic acid and formalin-induced nociception was not effectively removed by NAL; MA (20 mg/kg and 40 mg/kg) effectively reduced the duration of biting/licking the capsaicin-injected paw with inhibition rates of 29.5% and 64.4%, respectively; MA (20 mg/kg and 40 mg/kg) distinctly shortened the time spent in biting/licking the glutamate-injected paw by 30.9% and 56.1%, respectively. In summary, MA induces significant peripheral anti-nociceptive effect, and the anti-nociceptive activities probably involve the modulation of glutamatergic systems and vanilloid systems (TRPV1) instead of the opioidergic system.

Effects of Maxing Shigan Decoction on IL-6/STAT3 Signaling Pathway and TRPV1 Receptor in Rats with Cough Variant Asthma / 广州中医药大学学报

Objective To investigate the therapeutic effects and mechanisms of Maxing Shigan Decoction on cough variant asthma(CVA)rats.Methods Sixty rats were randomly divided into normal group,model group,low and high dose groups of Maxing Shigan Decoction,and high-dose of Maxing Shigan Decoction + signal transducer and activator of transcription 3(STAT3)activator Colivelin(Col)group,12 rats in each group.Except for the normal group,the CVA model was constructed by intraperitoneal injection of ovalbumin combined with moxa fumigation in all other groups of rats.After the corresponding treatment,the rats were observed for signs and cough counts,airway resistance(RE)was detected by pulmonary function meter,eosinophils(EOS)were counted by Diff-Quik staining,histopathological features of the lungs and bronchial tubes were observed by hematoxylin-eosin(HE)staining method,and the lung tissues were detected by enzyme-linked immunosorbent assay(ELISA)for monocyte chemotactic protein 1(MCP-1),and tumor necrosis factor α(TNF-α),and the protein expression levels of interleukin 6(IL-6),STAT3,and transient receptor potential vanilloid-1 channel(TRPV1)were detected by Western Blot.Results Compared with the normal group,rats in the model group showed obvious asthma symptoms,severe inflammatory cell infiltration was seen in the lung tissue,bronchial epithelial cell necrosis,ciliated adhesion,mucus,and RE,EOS number,MCP-1 and TNF-α contents,and protein expression levels of IL-6,STAT3,TRPV1 were elevated(P＜0.05);compared with the model group,rats in the low-and high-dose groups of Maxing Shigan Decoction showed significant improvement in asthma symptoms,reduction in lung and bronchial injury,and dose-dependent reduction in RE,EOS number,MCP-1 and TNF-α contents,and protein expression levels of IL-6,STAT3,and TRPV1(P＜0.05);compared with the high-dose group of Maxing Shigan Decoction,the rats in the high-dose Maxing Shigan Decoction+Col group showed increased asthma,increased lung and bronchial injury,and increased RE,EOS number,MCP-1 and TNF-α contents,and protein expression levels of IL-6,STAT3,and TRPV1(P＜0.05).Conclusion Maxing Shigan Decoction can effectively improve cough variant asthma in rats,and its mechanism is related to the inhibition of IL-6/STAT3 signaling pathway and the high expression of TRPV1.

The protective mechanism of TRPV4 channel inhibitor on blood-brain barrier damage after traumatic brain injury in rats / 沈阳医学院学报

Objective:To investigate the protective mechanism of TRPV4 channel inhibitor on blood-brain barrier(BBB)damage after traumatic brain injury(TBI).Methods:The TBI rat model was established.TRPV4 channel inhibitor HC067047 or PKC-δ inhibitor Rottlerin was used to detect changes in BBB permeability,neurological function score,and the expression of microvascular endothelial tight junction proteins ZO-1 and ZO-2 in brain injury areas after TBI.Results:Compared with the Sham group,BBB permeability significantly increased,brain neurological function score significantly decreased,and the expression of ZO-1 and ZO-2 significantly decreased in TBI group(P＜0.05).Compared with the TBI group,after administration of HC067047 or Rottlerin,changes in BBB permeability,brain neurological function score,the expression of ZO-1 and ZO-2 were partially reversed(P＜0.05).Conclusions:TBI-induced BBB injury may be mediated by TRPV4 channel regulating PKC-δ signaling pathway to affect the expression of tight junction proteins ZO-1 and ZO-2.Inhibition of TRPV4 channel function or PKC-δ signal molecule can partially alleviate BBB damage induced by TBI.This study may provide new ideas for the treatment of clinical TBI.

Mechanism of Huangwu Ganfu Ointment in Treatment of Peripheral Inflammatory Hyperalgesia of Knee Osteoarthritis Based on TRPV1 / 中国实验方剂学杂志

ObjectiveTo observe the regulatory effect of Huangwu Ganfu ointment on transient receptor potential anchor protein 1 （TRPV1） receptor expression， macrophage polarization， and p38 mitogen-activated protein kinase （p38 MAPK） signaling pathway in synovial tissue of knee osteoarthritis （KOA） rats with yang deficiency and cold coagulation syndrome and explore the mechanism of relieving peripheral inflammatory hyperalgesia of KOA. MethodForty-eight male SD rats were randomly divided into blank group， model group， high-dose， middle-dose， and low-dose groups of Huangwu Ganfu ointment （9.3， 4.65， 2.325 g·kg-1）， and celecoxib group （20.82 mg·kg-1）. The KOA rat model of yang deficiency and cold coagulation syndrome was established through climate box and swimming for two weeks combined with an injection of sodium iodoacetate （MIA） in the articular cavity. After continuous administration for four weeks， the general condition of rats in each group was observed， and the pain withdrawal threshold （PWT） and joint diameter induced by mechanical stimulation were recorded. The expression levels of interleukin-1β （IL-1β）， tumor necrosis factor-α （TNF-α）， nerve growth factor （NGF）， and calcitonin gene-related peptide （CGRP） inflammatory factor were detected by enzyme-linked immunosorbent assay （ELISA）， and the histopathological changes of synovial tissue of the knee joint were observed by hematoxylin-eosin （HE） staining. Western blot was used to detect the protein expression of TRPV1， p38 MAPK， and p-p38 MAPK in synovial tissue of the knee joint， and immunofluorescence （IF） was used to evaluate the polarization of M1/M2 macrophages. ResultCompared with that in the blank group， the overall mental state of the model group was worse， and the autonomous activity was decreased. The body mass was lower， and the joint diameter was increased. The X-ray showed that the osteophyte at the edge of the joint proliferated， and the articular surface was obviously rough. The articular cavity was significantly narrowed， and the PWT was significantly decreased （P<0.01）. The contents of IL-1β， TNF-α， CGRP， and NGF in serum and synovium Krenn score increased significantly （P<0.01）. The protein expression of TRPV1 and p-p38 MAPK/p38 MAPK increased significantly （P<0.01）， and the proportion of M1 macrophages and M1/M2 increased （P<0.01）， while the proportion of M2 macrophages decreased （P<0.01）. Compared with model group， the body mass in the low， middle， and high dose groups of Huangwu Ganfu ointment increased to different degrees （P<0.05， P<0.01）. The diameter of the knee joint in the high dose group of Huangwu Ganfu ointment and celecoxib group decreased （P<0.01）. The recovery of PWT in the high and middle dose groups of Huangwu Ganfu ointment groups was more obvious （P<0.05）. The contents of IL-1β and CGRP in the serum of rats in each administration group were significantly decreased （P<0.01）， and the content of serum TNF-α in the celecoxib group and high dose group of Huangwu Ganfu ointment decreased significantly （P<0.05）. The content of serum NGF in the middle dose group of Huangwu Ganfu ointment decreased significantly （P<0.05）， and the synovium Krenn score decreased in the high dose group of Huangwu Ganfu ointment （P<0.05）. In addition， the protein expression of TRPV1 and p-p38 MAPK/p38 MAPK in synovial tissue decreased significantly in all groups of Huangwu Ganfu ointment （P<0.01）. The proportion of M1 macrophages in synovial tissue in the celecoxib group and all groups of Huangwu Ganfu ointment decreased （P<0.01）， and the proportion of M2 macrophages in the high dose group of Huangwu Ganfu ointment increased （P<0.05）. The M1/M2 in the middle and high dose groups of Huangwu Ganfu ointment decreased （P<0.05）. ConclusionHuangwu Ganfu ointment can mediate the polarization of macrophages to reduce the inflammatory reaction of KOA， alleviate the release of inflammatory pain mediators， and lower the protein expression of TRPV1. The mechanism may be related to the p38 MAPK signaling pathway， so as to improve the peripheral hyperalgesia of KOA.

Research progress of TRPV4 in ocular pathophysiological function / 国际眼科杂志(Guoji Yanke Zazhi)

Transient receptor potential vanilloid receptor 4(TRPV4)is a non-selective cation channel responsible for sensing changes in cell swelling, temperature, mechanical stretch, shear stress and osmotic pressure by regulating transmembrane calcium signaling and thereby influencing gene expression, cell morphology, and cytoskeletal construction. TRPV4 is widely expressed throughout the body. Intraocularly, TRPV4 is functionally expressed in the cornea, lens, ciliary body, trabecular meshwork and retina. In this article, the expression and physiopathological functions of TRPV4 in various tissues of the eye were described. With the in-depth study of TRPV4 in ocular pathophysiological functions, TRPV4 may become a potential drug target in corneal injury repair, glaucoma and retinal angiogenesis, but further in-depth study is still needed.

Analysis on Mechanism of Huangwu Ganfu Ointment in Relieving Knee Osteoarthritis Pain Based on Network Pharmacology and Experimental Verification / 中国中医药信息杂志

Objective To analyze the mechanism of Huangwu Ganfu Ointment in relieving pain of knee osteoarthritis(KOA)based on network pharmacology;To verify it in animal experiments.Methods The active components of Huangwu Ganfu Ointment were obtained by TCMSP database,PubChem database and SwissADME platform,the effective components were screened,and the targets were obtained from SEA database.KOA disease-related targets were obtained from GeneCards,OMIM and other databases,and the intersection targets were obtained.A effective component-target-disease network was constructed using Cytoscape 3.9.0 Software.Protein-protein interaction(PPI)network was constructed by STRING database and core targets were screened.GO and KEGG enrichment analysis of intersection targets were analyzed using DAVID platform.The KOA rat model with cold and damp syndrome was established,and the intervention of Huangwu Ganfu Ointment was carried out.The efficacy was observed and the core target expressions were detected.Results Totally 104 effective components were screened from Huangwu Ganfu Ointment,and 59 potential targets were obtained for treating KOA.PPI network interaction analysis obtained the important targets of IL6,IL1B and PTGS2.KEGG enrichment results showed that Huangwu Ganfu Ointment may involve 84 signaling pathways such as IL-17,TNF,TRP and NF-κB in the treatment of KOA,most of which were related to inflammation.The results of animal experiments showed that Lecuesne MG scores increased in the model rats(P<0.05),and paw withdrawal threshold(PWT)significantly decreased(P<0.05).Compared with model group,PWT in Huangwu Ganfu Ointment medium-and high-dosage groups were significantly recovered,and synovitis Krenn score decreased(P<0.05).The Mankin score of cartilage tissue of Huangwu Ganfu Ointment high-dosage group decreased(P<0.05).The contents of IL-6 and IL-1β in all Huangwu Ganfu Ointment groups decreased(P<0.01).Huangwu Ganfu Ointment medium-and high-dosage groups could down-regulate the expression of TRPV1 protein(P<0.05,P<0.01).Conclusion The mechanism of Huangwu Ganfu Ointment in alleviating the pain of KOA may be related to reducing inflammatory response,reducing the release of inflammatory factors of IL-1β and IL-6,alleviating inflammatory pain sensitivity of KOA,and down-regulating the expression level of TRPV1.

Pathological role of PKC/TRPV1 pathway in trigeminal neuralgia in rats / 安徽医科大学学报

Objective @#To investigate the pathological role of detect protein kinase C(PKC)/ transient receptor potential vanilloid subtype 1 ( TRPV1) pathway in trigeminal neuralgia ( TN) in rats.@*Methods @#The infraorbital nerve⁃chronic constriction injury (ION⁃CCI) was used to establish a rat model of TN. The rats were randomly divided into Sham group , CCI group , CCI + DMSO group and CCI + GF109203X ( a PKC inhibitor) group. The mechanical pain threshold of the rats was measured using a Von Frey brush. qRT⁃PCR and Western blot were used to detect PKC and TRPV1 in the trigeminal ganglion (TG) . HE staining was used to observe the pathological changes of TG.@*Results @#The mechanical pain threshold significantly decreased (P < 0. 05) , and the expression of phosphorylated PKC(p⁃PKC) and TRPV1 in TG significantly increased in the CCI group (P < 0. 05) . Histopathological results showed that compared with the Sham group , the CCI group observed significant changes in TG such as increased inflammatory cell infiltration and nerve cell swelling. Injection of GF109203X effectively reduced the phosphorylation of PKC and the expression of TRPV1 in the TG of rats , and the mechanical pain threshold of the rats increased (P < 0. 05) . Under the light microscope , cell swelling and inflammatory cells in the TG were reduced.@*Conclusion @#PKC/TRPV1 pathway may be involved in trigeminal neuralgia in rats.

Esketamine alleviates hypoxia/reoxygenation injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration

Abstract Objective This study aimed to investigate the effect of Esketamine (ESK) on the Hypoxia/Reoxygenation (H/R) injury of cardiomyocytes by regulating TRPV1 and inhibiting the concentration of intracellular Ca2+. Methods The H/R injury model of H9c2 cardiomyocytes was established after 4h hypoxia and 6h reoxygenation. H9c2 cells were treated with different concentrations of ESK or TRPV1 agonist capsaicin (10 μM) or TRPV1 inhibitor capsazepine (1 μM). Cell viability was detected by CCK-8 method, and apoptosis by flow cytometry. Intracellular Ca2+ concentration was evaluated by Fluo-4 AM. LDH, MDA, SOD, and GSH-Px were detected with corresponding commercial kits. TRPV1 and p-TRPV1 proteins were detected by Western blot. Results After H/R, H9c2 cell viability decreased, apoptosis increased, intracellular Ca2+ concentration increased, LDH and MDA levels increased, SOD and GSH-Px levels decreased, and p-TRPV1 expression increased. ESK treatment rescued these changes induced by H/R. After up-regulating TRPV1, the protective effect of ESK on H/R injury of H9c2 cells was weakened, while down-regulating TRPV1 could further protect against H/R injury. Conclusion ESK alleviates H/R injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration.

TRPV4-induced Neurofilament Injury Contributes to Memory Impairment after High Intensity and Low Frequency Noise Exposures / 生物医学与环境科学（英文）

OBJECTIVE@#Exposure to high intensity, low frequency noise (HI-LFN) causes vibroacoustic disease (VAD), with memory deficit as a primary non-auditory symptomatic effect of VAD. However, the underlying mechanism of the memory deficit is unknown. This study aimed to characterize potential mechanisms involving morphological changes of neurons and nerve fibers in the hippocampus, after exposure to HI-LFN.@*METHODS@#Adult wild-type and transient receptor potential vanilloid subtype 4 knockout (TRPV4-/-) mice were used for construction of the HI-LFN injury model. The new object recognition task and the Morris water maze test were used to measure the memory of these animals. Hemoxylin and eosin and immunofluorescence staining were used to examine morphological changes of the hippocampus after exposure to HI-LFN.@*RESULTS@#The expression of TRPV4 was significantly upregulated in the hippocampus after HI-LFN exposure. Furthermore, memory deficits correlated with lower densities of neurons and neurofilament-positive nerve fibers in the cornu ammonis 1 (CA1) and dentate gyrus (DG) hippocampal areas in wild-type mice. However, TRPV4-/- mice showed better performance in memory tests and more integrated neurofilament-positive nerve fibers in the CA1 and DG areas after HI-LFN exposure.@*CONCLUSION@#TRPV4 up-regulation induced neurofilament positive nerve fiber injury in the hippocampus, which was a possible mechanism for memory impairment and cognitive decline resulting from HI-LFN exposure. Together, these results identified a promising therapeutic target for treating cognitive dysfunction in VAD patients.

Intervention effect of Qufeng Gutong Cataplasm on myofascial pain syndrome in rats and its mechanism / 中国中药杂志

This paper aims to investigate the intervention effect of Qufeng Gutong Cataplasm(QFGT) on myofascial pain syndrome(MPS) in rats and to preliminarily explain its mechanism from the perspective of improving muscle inflammation and pain. Male SD rats were divided into 6 groups, namely normal group, model group, positive control drug(Huoxue Zhitong Ointment, HXZT) group, and low, medium, and high-dose QFGT groups(75, 150, and 300 mg·d~(-1)). The rat model of MPS was established by striking combined with centrifugation for 8 weeks, during which QFGT and HXZT were used for corresponding intervention. Standard VonFrey fiber was used to evaluate the mechanical pain threshold, and acetone was used to detect the cold pain threshold. The electrophysiological activity of muscle at trigger point was detected, and the electromuscular analysis of trigger point was performed. CatWalk gait analyzer was used to detect pain-induced gait adaptation changes. The hematoxylin-eosin(HE) staining was used to observe the pathological changes in muscle and skin tissues at the trigger point of rats. Immunohistochemistry was used to detect the expression of capsaicin receptor transient receptor potential vanilloid 1(TRPV1) in muscle tissues and interleukin(IL)-33 in skin tissues at the trigger point. The protein expression levels of TRPV1, protein kinase B(Akt), phosphorylated protein kinase B(p-Akt), IL-1β, and tumor necrosis factor-α(TNF-α) in muscle tissues at the trigger point were detected by Western blot. The results showed that as compared with the model group, the mechanical pain threshold and cold pain threshold of rats in other groups were increased after treatment with QFGT. The spontaneous electromyography(EMG) activity was observed in the model group, but QFGT alleviated the EMG activity in a dose-dependent manner. Gait analysis showed that standing duration, average intensity, swing speed, maximum contact point, maximum contact area, paw print length, paw print width, and paw print area were significantly improved in all QFGT groups. Pathological results showed that the disorder of muscle arrangement at the trigger point was decreased, muscle fiber adhesion and atrophy were reduced, and inflammatory cell infiltration was alleviated after treatment with QFGT. In addition, QFGT and HXZT both inhibited the protein expression of TRPV1, PI3K, Akt, p-Akt, IL-1β, and TNF-α in the muscle tissues of rats with MPS. However, there was no significant difference in the pathological structure and expression of IL-33 in the treated skin as compared with the normal group. The related results have proved that QFGT can inhibit the release of inflammatory factors by inhibiting the TRPV1/PI3K/Akt signaling pathway in the muscle trigger point of rats with MPS and finally attenuate the atrophy and adhesion of local muscles and inflammatory infiltration, thereby relieving the muscle pain of rats with MPS, and local administration has no skin irritation.

Preliminary study of TRPV4 affects chondrocyte degeneration / 中国骨伤

OBJECTIVE@#To explore and verify that transient receptor potential vanilloid 4(TRPV4) affects chondrocyte degeneration.@*METHODS@#Neonatal SD rats were selected, primary chondrocytes were extracted, and identified by toluidine blue staining and alcian blue staining;an in vitro chondrocyte inflammation model was constructed by IL-1β, and TRPV4 inhibitor was used to treat chondrocytes under inflammatory conditions, and the chondrocytes were treated by RT-PCR method was used to detect matrix metallopeptidase 13(MMP-13), a disintegrin and metalloproteinase with thrombospondin 5, (ADAMTS-5)、nitric oxide synthase 2(NOS2)、Collagen, type II alpha 1(Col2α1)and aggrecan (Acan) mRNA in chondrocytes; primary chondrocytes were treated with different concentrations of TRPV4 overexpression plasmid, and the optimal overexpression dose was screened. The mRNA expressions of TRPV4, MMP-13, ADAMTS-5, NOS2, Col2α1 and Acan in chondrocytes under the optimal TRPV4 overexpression dose were detected.@*RESULTS@#Toluidine blue staining and Alcian blue staining identified the extracted cells as primary chondrocytes;RT-PCR showed that TRPV4, MMP-13, ADAMTS-5, NOS2 mRNA in chondrocytes treated with TRPV4 inhibitor under inflammatory conditions. The expression of Col2α1 mRNA was significantly decreased (P<0.05), and the expression of Col2α1 mRNA was increased (P<0.05). Although there was no significant difference in the expression of Acan mRNA, the overall trend was also increasing. The expression of Col2α1 and Acan mRNA in chondrocytes was significantly decreased (P<0.05), and the expression of NOS2 mRNA was increased(P<0.05), but there was no significant difference in MMP-13 and ADAMTS-5 (P>0.05).@*CONCLUSION@#Inhibiting the expression of TRPV4 can down-regulate the expression of genes related to chondrocyte degeneration.

The role of thermosensitive transient receptor potential vanilloid channel in the dissimilation of itching sensitized by warm in atopic dermatitis / 中国医师杂志

Atopic dermatitis (AD) is an inflammatory skin disease characterized by itch. Transient receptor potential vanilloid (TRPV) receptor subtype channel can be activated by different ranges of harmless temperature, and plays an important role in the warm itching in AD. Inhibitors of TRPV channel can alleviate the symptoms of AD, and may be used as a new target for treatment. This paper introduces the role of thermosensitive TRPV channel in the alienation of itching sensitized by warm in AD.

Role of TRPV4 in dexmedetomidine-induced improvement in cognitive function in mice with mechanical ventilator-caused brain injury / 中华麻醉学杂志

Objective:To evaluate the role of transient receptor potential vanillic acid 4 (TRPV4) in dexmedetomidine-induced improvement in cognitive function in mice with mechanical ventilator-caused brain injury.Methods:Ninety clean-grade healthy male C57BL6 mice, weighing 20-25 g, aged 8-12 weeks, were divided into 5 groups ( n=18 each) using a random number table method: control group (group C), mechanical ventilation group (group V), HC-067047 group (group H), dexmedetomidine group (group D), and dexmedetomidine+ GSK1016790A group (group DG). In group C, the animals breathed air spontaneously for 6 h without mechanical ventilation. In group V, the animals were mechanically ventilated for 6 h. In group H, TRPV4 blocker HC-067047 10 mmol was injected into the cerebral ventricle at 3 and 6 h of mechanical ventilation. In D and DG groups, dexmedetomidine 50 μg/kg was intraperitoneally injected at 30 min before mechanical ventilation. In group DG, TRPV4 agonist GSK1016790A 5 μmol was injected into the cerebral ventricle at 60 min before mechanical ventilation. Morris water maze test was performed on 6 mice in each group at 1 day before mechanical ventilation and 3 and 7 days after mechanical ventilation. Six mice in each group were randomly selected and sacrificed at 1 day after mechanical ventilation, and the brain tissue was taken for determination of the neuronal apoptosis in hippocampal CA1 area by TUNEL method, and the apoptosis index was calculated. Six mice in each group were randomly selected and sacrificed at 1 day after mechanical ventilation, and the hippocampal tissues were taken for determination of the expression of TRPV4, serine-threonine protein kinase (Akt), phosphorylated Akt (p-Akt), Bcl-2, Bax and caspase-3 by Western blot. Results:Compared with group C, the escape latency was significantly prolonged and the number of crossing the original platform was reduced at 3 and 7 days after mechanical ventilation, the expression of TRPV4 and caspase-3 was up-regulated, the ratio of Bcl-2/Bax was decreased, and the apoptosis index of neurons was increased in group V and group DG ( P<0.05). Compared with group V, the escape latency was significantly shortened and the number of crossing the original platform was increased at 3 and 7 days after mechanical ventilation, the expression of TRPV4 and caspase-3 was down-regulated, the expression of p-Akt was up-regulated, the ratio of Bcl-2/Bax was increased, and the apoptosis index of neurons was decreased in group D and group H ( P<0.05). Compared with group D, the escape latency was significantly prolonged at 3 and 7 days after mechanical ventilation, the number of crossing the original platform was reduced, the expression of TRPV4 and caspase-3 was up-regulated, the expression of p-Akt was down-regulated, the ratio of Bcl-2/Bax was decreased, and the apoptosis index of neurons was increased in group DG ( P<0.05). Conclusions:TRPV 4 is involved in dexmedetomidine-induced improvement in cognitive function, which is related to up-regulation of p-Akt expression and inhibition of apoptosis in hippocampal neurons in mice with mechanical ventilation-caused brain injury.

Research Development in Patients with Olmsted Syndrome / 罕见病研究

Olmsted syndrome (OS) is an extremely rare hereditary skin disease, that is usually characterized by mutilating palmoplantar keratoderma (PPK) and periorificial keratotic plaques. The diagnosis of this disease depends primarily on the clinical presentation and OS has to be differentiated from other disorders associated with hyperkeratosis. In recent years, there have been many advances in molecular genetic research on the pathogenesis of the disease. The genes that can cause disease after specific mutations include TRPV3, MBTPS2/S2P and PERP. Therefore, genetic testing has become one of the important methods for the diagnosis of this disease.OS treatment is difficult, and conventional therapy uses topical drugs to soften the cuticle of the skin, or oral Avi A.Excision of palmoplantar keratosis may also be used for constricting rings that severely restrict movement, but they often reoccur after initial improvement. In terms of precision treatment, researchers have tried the small molecule drugs erlotinib and sirolimus and have achieved some results. This paper summarizes the etiology, pathogenesis, clinical manifestations, diagnosis, treatment and prognosis of OS, in order to improve the clinicans' awareness of OS.

Regulation of high-fat diet-induced microglial metabolism by transient receptor potential vanilloid type 1 / 上海交通大学学报（医学版）

Objective·Transcriptomic and lipidomic analysis techniques were used to investigate the role of transient receptor potential vanilloid type 1(TRPV1)channel activation in the regulation of high-fat diet-induced microglial metabolism.Methods· Eight-week-old C57BL/6J mice(WT)and Trpvl-/-(KO)mice were used as experimental animals,and fed high-fat diet(HFD)for 3 days,7 days,and 8 weeks to induce modelling(WT and KO groups,n=3;WT-HFD and KO-HFD groups,n=4).TRPV1 channel expression and cellular localisation were measured by immunofluorescence in the brains of mice in the WT-HFD and KO-HFD group.RNA sequencing and liquid chromatography-mass spectrometry were performed to determine the brain phenotype of mice in the WT-HFD and KO-HFD groups.Results·The expression level of Trpvl mRNA in microglia was significantly increased in mice in the WT-HFD group compared to mice in the WT group.The expression levels of genes related to brain lipid metabolism,mitochondrial function,glucose transfer,and glycolysis were down-regulated in the KO-HFD group of mice compared with the WT-HFD group of mice.Lipidomic analysis showed that although lipids accumulated in the brain tissue of mice in the KO-HFD group,Trpv1 knockdown attenuated HFD-induced microglia activation,and in addition the TRPV1 agonist capsaicin attenuated palmitate-induced depolarisation of mitochondrial membrane potential in vitro.Conclusion·Together,these findings suggest that TRPV1 regulates lipid and glucose metabolism in microglia via fuel availability driven by a mitochondrial mechanism.

Role and Mechanism of TRPV1 and NaV1.8 in Esophageal Hypersensitivity / 胃肠病学

Background:Gastroesophageal reflux disease(GERD)is a common digestive system disease with typical symptoms of acid reflux and heartburn,and high sensitivity of esophagus is an important cause of heartburn and other symptoms.TRPV1 and NaV1.8 may play an important role in the regulation of esophageal hypersensitivity,and the specific mechanism is not yet clear.Aims:To detect the expression levels of TRPV1 and NaV1.8 in esophageal sensory neuron in GERD state and explore their role in mediating esophageal hypersensitivity.Methods:Twelve guinea pigs were randomly divided into control group and GERD group.The GERD guinea pig model was established by drinking hydrochloric-pepsinogen acid water,the body mass of guinea pigs was monitored,the esophageal inflammatory histological score was performed,and the successful construction of the GERD model was verified by measuring the expression indicators of inflammatory factors.The heart rate variability method was used to detect whether the guinea pigs were in the state of visceral hypersensitivity.The expression and co-expression of TRPV1 and NaV1.8 in esophagus,nodular ganglion and jugular ganglion were detected by immunofluorescence,Western blot and real-time fluorescence quantification.Results:Compared with the control group,the score of esophageal inflammatory histology in GERD group was much higher than that in the control group(0.96 vs.0.22).The contents of esophageal inflammatory factors interleukin(IL)-1β,IL-6 and tumor necrosis factor(TNF)-α were significantly increased(P<0.05),while the contents of anti-inflammatory factor IL-10 were decreased(P<0.05).The index of heart rate variability,low frequency to high frequency ratio(LF/HF)had no significant difference between the GERD group and the control group(P>0.05),and the LF/HF in the GERD group was higher than that in the control group after the molding(P<0.05).In esophagus and jugular,the expression levels of TRPV1 and NaV1.8 in GERD group were increased and the co-expression levels were up-regulated(P<0.05),while the expression levels in nodose were not significantly changed(P>0.05).Conclusions:In the case of esophageal acid exposure,the expression levels of TRPV1 and NaV1.8 in the esophageal mucosal epithelium increased,while the expression levels in jugular ganglion were up-regulated,thus promoting the transmission of pain signals in the vagus nerve pathway,and ultimately leading to the occurrence of esophageal hypersensitivity.

The effects of linalool on transient receptor potential vanilloid 1 pathway and its role in alleviating visceral hypersensitivity in rats with irritable bowel syndrome / 中华消化杂志

Objective:To observe the effects of linalool on central and alleviating peripheral nervous system through transient receptor potential vanilloid 1 (TRPV1) pathway and its role in alleviating visceral hypersensitivity in irritable bowel syndrome (IBS).Methods:Thirty-six female newborn Sprague-Dawley (SD) rat pups in specific pothogen free was selected, among which 30 rats were used for behavioral experiments and 6 rats for electrophysiological experiment. In behavioral experiments, 30 newborn SD rats were randomly divided into normal control group (0.2 mL 0.9% sodium chloride solution was injected into the colorectal), neonatal colonic inflammation (NCI) group (0.2 mL 0.5% acetic acid was injected into the colorectal), linalool 20, 50 and 100 mg/kg groups (after NCI model successfully established, the rat were gavaged with linalool 20, 50 or 100 mg/kg at 5 weeks old). At 6 weeks old, abdominal withdrawal reflex (AWR) and pressure value of pain threshold (inflation pressure value at AWR score of 3) was observed by colorectal distention test. One hour after behavioral experiments, the expression of TRPV1 at protein level in colonic mucosa and spinal cord of each group was detected by Western blotting and immunohistochemistry. In electrophysiological experiment, female SD rats aged 6 to 7 weeks were selected to make in vitro transverse sections of the spinal cord. Five to eight neurons were randomly selected from each rat for whole-cell patch-clamp recording. The effects of linalool, tetrodotoxin and anti capsaicinand on the spontaneous excitatory postsynaptic current (sEPSC) of substantiagelatinosa neurons was recorded. Independent sample t test and paired t test were used for statistical analysis. Results:The AWR score of rats in NCI group was higher than those in normal control group, linalool 20 mg/kg group, linalool 50 mg/kg group and linalool 100 mg/kg group at 40 mmHg (1 mmHg=0.133 kPa) pressure (2.5±0.2 vs. 1.0±0.3, 1.5±0.3, 1.5±0.2, and 1.5±0.2, respectively), at 60 mmHg pressure the AWR score was higher than those in normal control group, linalool 50 mg/kg group and linalool 100 mg/kg group (3.8±0.2 vs. 2.3±0.4, 2.3±0.5, and 2.0±0.3, respectively), and the differences were statistically significant ( t=4.39, 2.45, 3.16, 3.16, 3.31, 2.88 and 5.97; P=0.001, 0.034, 0.010, 0.010, 0.008, 0.028, and<0.001). The pain threshold of rats in NCI group was lower than those of normal control group, linalool 20 mg/kg group, linalool 50 mg/kg group and linalool 100 mg/kg group ((35.8±2.0) mmHg vs. (55.8±1.5), (49.2±2.4), (53.3±2.1), and (55.0±1.8) mmHg, respectively), and the differences were statistically significant ( t=-7.91, -4.28, -6.01, and -7.06; P<0.001, =0.002, <0.001, and <0.001). The results of Western blotting showed that the relative expression of TRPV1 at protein level in colorectal tissues of rats in NCI group was higher than those of normal control group, linalool 20 mg/kg group, linalool 50 mg/kg group and linalool 100 mg/kg group (0.86±0.03 vs. 0.32±0.03, 0.68±0.01, 0.45±0.03, and 0.56±0.02, respectively), and the relative expression of TRPV1 at protein level in spinal dorsal horn was higher than those of normal control group, linalool 20 mg/kg group, linalool 50 mg/kg group and linalool 100 mg/kg group (0.91±0.02 vs. 0.34±0.03, 0.72±0.03, 0.51±0.06, and 0.63±0.05), and the differences were statistically significant ( t=12.44, 5.14, 9.68, 7.69, 19.14, 5.13, 6.72, and 5.60; P<0.001, <0.001, <0.001, <0.001, <0.001, <0.001, =0.001, and <0.001). There were no statistically significant differences in the frequency and the outward current of sEPSC in neurons of same glial region among rats with 2 mmol/L linalool gavaged for 4 minutes, 0.5 μmol/L tetrodotoxin and 2 mmol/L linalool gavaged for 4 minutes ( n=5, (23.84±4.81) Hz vs. (20.54±5.71) Hz, (7.60±0.35) pA vs. (7.62±0.75) pA, both P>0.05). The frequency of sEPSC administered with 2 mmol/L linalool gavaged for 4 minutes was higher than that of neurons in the same glial area administered with 10 μmol/L capsazepine and 2 mmol/L linalool gavaged for 4 minutes ( n=5, (20.17±2.55) Hz vs.(14.09±2.98) Hz), and the difference was statistically significant ( t=3.58, P=0.021); however there was no statistically significant difference in the outward current ((7.42±0.78) pA vs. (7.03±1.32) pA, P>0.05). Conclusion:Linalool can relieve visceral hypersensitivity in IBS partially through TRPV1 pathway, which may be related to the hyperpolarization of the membrane potential of neurons in glial region.

Research progress of TRPV4 in glaucoma optic neuropathy / 国际眼科杂志(Guoji Yanke Zazhi)

Glaucomatous optic neuropathy(GON)is the difficulty of glaucoma treatment. In recent years, a variety of theories have been put forward about the pathogenesis of GON, but none of them can explain the principle of optic neuropathy caused by all types of glaucoma, which makes the disease difficult to treat in clinical treatment and is not conducive to early intervention. The latest research found that the transient receptor potential channel vanillic acid subfamily 4(TRPV4)in the retina plays an important role in various pathogenesis of GON. This article will review TRPV4 and its role in the occurrence and development of GON in order to find a common “connection point” for the multiple mechanism theories of GON, which will contribute to further understanding and clinical treatment of the disease.

Propofol relieves the subcutaneous chloroquine-induced pruritus in rats via TRPV1 and CB1 receptors of spinal cord / 中国临床药理学与治疗学

AIM: To explore the possible mechanism of propofol in alleviating pruritus induced by subcutaneous injection of chloroquine in rats. METHODS: The pruritus model of chloroquine in SD rats was established and the administration time was determined. 18 rats with successful pruritus model induced by subcutaneous injection of chloroquine were randomly divided into NS group, I group and P group. Normal saline 80 μL/kg, fat emulsion 80 μL/kg and propofol 0.8 mg/kg were injected through internal jugular vein catheter 5 minutes after subcutaneous injection of chloroquine. Another 6 rats were randomly selected as group C, and the same volume of normal saline as the other 3 groups was injected subcutaneously in the back of the neck and through the internal jugular vein catheter. The rats were killed 16 minutes after the corresponding drugs were injected into the internal jugular vein. The expressions of TRPV1 and CB1 receptors in the spinal cord were detected by Western blot. RESULTS: Compared with NS group and I group, the expression level of TRPV1 receptor in the spinal cord of P group rats was significantly increased (P<0.01), while there was no statistically significant difference between C group, NS group, and I group; The expression level of CB1 receptor was significantly higher than that of group C, NS, and I (P<0.05), while there was no statistically significant difference between group C, NS, and I. CONCLUSION: Propofol can significantly alleviate pruritus caused by subcutaneous injection of chloroquine in rats, which may exert an antipruritic effect by increasing the expression of TRPV1 and CB1 receptors in the spinal cord of rats.