The mechanism of chlorogenic acid against neuropathic pain induced by cisplatin / 药学学报

This study aimed to investigate the analgesic effect of chlorogenic acid on cisplatin-induced neuropathic pain and explored the underlying molecular mechanisms. The animal experimental protocol has been reviewed and approved by Laboratory Animal Ethics Committee of Xinxiang Central Hospital, in compliance with the Institutional Animal Care Guidelines. Von Frey hair and a radiant heat was employed to measure mechanical allodynia and thermal hyperalgesia; Western blot was used to examine transient receptor potential vanilloid type-1 (TRPV1) protein expression in the rat dorsal root ganglion (DRG); patch clamp was used to record TRPV1 currents in DRG neurons. The experimental results showed that chlorogenic acid could attenuate cisplatin-induce mechanical allodynia and thermal hyperalgesia in rats. The expression of TRPV1 protein in DRGs was increased in cisplatin-treated rats, while chlorogenic acid also could reverse cisplatin-induced the upregulation of TRPV1 protein. Forthermore, chlorogenic acid could attenuate cisplatin-mediated the upregulation of TRPV1 current density. These above results indicated that chlorogenic acid could alleviate cisplatin-induced pain hypersensitivity through inhibition of the expression and function of TRPV1 in rats.

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.

Effects of transient receptor potential vanilloid 4 inhibitor HC067047 on anxiety-like behavior in mice induced by lipopolysaccharide / 解剖学报

Objective To investigate the effect of transient receptor potential vanilloid 4 (TRPV4) inhibitor HC067047 on anxiety-like behavior in mice induced by lipopolysaccharide (LPS). Methods Totally 48 male C57BL/6 mice were randomly divided into control group (NS), model group (LPS) and drug intervention group (HC + LPS). Anxiety mouse model was established by intraperitoneal injection of 0.83 mg/kg LPS. The HC + LPS group was intraperitoneally injected with HC067047 (10 mg/kg) 30 minutes before LPS injection, and the NS group and LPS group were injected with equal volume of normal saline. Open field test and social interaction experiments were used to detect anxiety-like behaviors in each group of mice; Immunohistochemical chemistry and Western blotting were used to detect the expression of TRPV4, inducible nitric oxide synthase (iNOS), neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) in the hippocampus. Results Immunohistochemical and Western blotting experiments showed that, compared with the NS group, the expression of TRPV4 in the hippocampus of the LPS group was significantly up-regulated (P<0.0001); In the open field test, compared with the NS group, the total distance (P < 0.0001), the distance in the central area (P<0.01) and the time of in the central area mice in the LPS group reduced significantly (P< 0.01). HC067047 intervention reversed the activities of LPS model mice total distance (P < 0.05), the distance of activities in the central area (P < 0.001) and the time of in the central area (P < 0.01); In the social interaction test, compared with the NS group, the interaction time the unfamiliar mice reduced significantly in LPS group (P<0.01), which was reversed by HC067047 treatment (P< 0.01); Western blotting detection revealed that the expression of hippocampal iNOS (P<0.05), nNOS (P < 0.001), and eNOS (P < 0.001) in the LPS group were significantly higher than the NS group, which reduced remarkably by HC067047 treatment (iNOS P < 0.05, nNOS P < 0.01 and eNOS P < 0.01). Conclusion Inhibiting the expression of TRPV4 can improve the anxiety-like behavior, and this process may be related to anti-oxidative stress.

Improvement effect of Shegan Mahuang Decoction on rats with cold-induced asthma based on TRPV1/NRF-1/mtTFA pathway / 中国中药杂志

This study investigated the therapeutic effect of Shegan Mahuang Decoction(SGMHD) on cold-induced asthma in rats and explored its underlying mechanism. Seventy-two healthy male SD rats of specific pathogen free(SPF) grade were randomly divided into a blank group, a model group, a positive control group(dexamethasone, 0.4 mg·kg~(-1)), and low-, medium-, and high-dose SGMHD groups(3.2, 6.4, and 12.8 g·kg~(-1)). The blank group received saline, while the other groups were sensitized by intraperitoneal injection of ovalbumin(OVA) solution. Subsequently, the rats were placed in a cold chamber adjustable to 0-2 ℃, and OVA solution was ultrasonically nebulized to induce cold-induced asthma in rats. After three weeks of treatment, the general behaviors of rats were observed. Hematoxylin-eosin(HE) staining was used to evaluate pathological changes in lung tissues, periodic acid-Schiff(PAS) staining assessed mucin changes, and Masson staining was performed to examine collagen deposition. Enzyme-linked immunosorbent assay(ELISA) was used to measure the levels of the inflammatory factors interleukin-4(IL-4) and vascular endothelial growth factor(VEGF) in serum and bronchoalveolar lavage fluid(BALF). Real-time quantitative polymerase chain reaction(RT-PCR) was employed to assess the mRNA expression levels of transient receptor potential vanilloid subfamily member 1(TRPV1), nuclear respiratory factor 1(NRF-1), and mitochondrial transcription factor A(mtTFA) in lung tissues. Western blot was used to measure the protein expression levels of TRPV1, NRF-1, and mtTFA in lung tissues. Compared with the blank group, the model group exhibited signs of rapid respiration, increased frequency of defecation with looser stools, and disheveled and dull fur. Pathological results showed significant infiltration of inflammatory cells in lung tissues, narrowing of bronchial lumens, increased mucin secretion, and enhanced collagen deposition in the model group. Additionally, the levels of IL-4 and VEGF in serum and BALF were significantly elevated, and the mRNA and protein expression levels of TRPV1, NRF-1, and mtTFA in lung tissues were significantly increased. Compared with the model group, SGMHD improved the behaviors of rats, alleviated pathological changes in lung tissues, mucin production, and collagen deposition, significantly decreased the levels of IL-4 and VEGF in serum and BALF, and reduced the mRNA expression levels of TRPV1, NRF-1, and mtTFA in lung tissues, with the medium-dose SGMHD group showing the most significant effect. Moreover, the protein expression levels of TRPV1, NRF-1, and mtTFA in lung tissues were also reduced, with the medium-dose SGMHD group exhibiting the most significant effect. In conclusion, this study demonstrates that SGMHD can alleviate airway inflammation and inhibit airway remodeling in cold-induced asthma rats. These effects may be associated with the modulation of the TRPV1/NRF-1/mtTFA signaling pathway.

Mechanism of Renshentang in Treatment of Atherosclerosis Based on Autophagic Effect of TRPV1 on Arterial Smooth Muscle / 中国实验方剂学杂志

ObjectiveTo investigate the mechanism of Renshentang， recorded in Synopsis of Golden Chamber， in the treatment of atherosclerosis （AS） based on the autophagic effect of transient receptor potential vanilloid subtype 1 （TRPV1） on arterial smooth muscle. MethodFourteen SPF-grade 8-week-old male C57BL/6J mice were assigned to the normal group and 70 8-week-old apolipoprotein E knockout （ApoE-/-） mice were assigned to the experimental group. The AS model was induced by a high-fat diet in the mice in the experimental group for eight weeks. The model mice were then randomly divided into model group， low-， medium-， and high-dose Renshentang groups （2.715， 5.43， and 10.68 g·kg-1·d-1）， and simvastatin group （0.02 g·kg-1·d-1）. Drug treatment lasted eight weeks. Serum was taken and serum total cholesterol （CHO）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C）， and high-density lipoprotein cholesterol （HDL-C） levels were measured by assay kits to observe the changes in lipid levels in mice. The aorta was stained with hematoxylin-eosin （HE） to observe the overall pathology of the aortic root and oil red O staining was used to detect the lipid deposition in the aortic plaque and calculate the percentage of the aortic root area to the lumen area. The protein expression of TRPV1， adenylate-activated protein kinase （AMPK）， phosphorylated AMPK （p-AMPK）， autophagy effector-1 （Beclin-1）， and microtubule-associated protein 1 light chain 3 （LC3Ⅱ） in mouse aortic tissues was determined by Western blot. ResultCompared with the normal group， the model group showed increased serum CHO， TG， and LDL-C levels， decreased HDL-C， and increased aortic root plaque area （P<0.01）. Compared with the model group， the Renshentang groups showed decreased levels of CHO， TG， and LDL-C in serum （P<0.05， P<0.01）， especially in the low- and medium-dose Renshentang groups （P<0.01）. Compared with the normal group， the simvastatin group and the Renshentang groups showed reduced aortic root plaque area （P<0.05）， especially in the high-dose Renshentang group （P<0.01）. Compared with the normal group， the model group showed decreased relative expression levels of TRPV1， p-AMPK/AMPK， Beclin-1， and LC3Ⅱ/LC3Ⅰ（P<0.05， P<0.01）. Compared with the model group， the medium- and high-dose Renshentang groups showed increased relative expression levels of TRPV1， p-AMPK/AMPK， Beclin-1， and LC3Ⅱ/LC3Ⅰ（P<0.05，P<0.01）. ConclusionThe anti-AS effect of Renshentang recorded in Synopsis of Golden Chamber may be achieved by up-regulating TRPV1 expression to restore the level of autophagy mediated by AMPK.

TRPV1 participates in the protective effect of propolis on colonic tissue of ulcerative colitis / 中南大学学报(医学版)

OBJECTIVES@#Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) mainly characterized by inflammation, ulceration and erosion of colonic mucosa and submucosa. Transient receptor potential vanilloid 1 (TRPV1) is an important mediator of visceral pain and inflammatory bowel disease. This study aims to investigate the protective effect of water soluble propolis (WSP) on UC colon inflammatory tissue and the role of TRPV1.@*METHODS@#Male SD rats were randomly divided into 6 groups (n=8): a normal control (NC) group, an ulcerative colitis model (UC) group, a low-WSP (L-WSP) group, a medium-WSP (M-WSP) group, a high-WSP (H-WSP) group, and a salazosulfapyridine (SASP) group. The rats in the NC group drank water freely, and the other groups drank 4% dextran sulfate sodium (DSS) solution freely for 7 d to replicate the ulcerative colitis model. Based on the successful replication of the UC, the L-WSP, M-WSP, and H-WSP groups were given 50, 100, and 200 mg/kg of water-soluble propolis by gavage for 7 d, and the SASP group was given 100 mg/kg of sulfasalazine by gavage for 7 d. The body weight of rats in each group was measured at the same time every day, the fecal traits and occult blood were observed to record the disease activity index (DAI). After intragastric administration, the animals were sacrificed after fasted 24 h. Serum and colonic tissue were collected, and the changes of MDA, IL-6 and TNF-α were detected. The pathological changes of colon tissues were observed by HE staining, and the expression of TRPV1 in colon tissues was observed by Western blotting, immunohistochemistry, and immunofluorescence.@*RESULTS@#The animals in each group that drank DSS freely showed symptoms such as weight loss, decreased appetite, depressed state, and hematochezia, indicating that the model was successfully established. Compared with the NC group, DAI scores of other groups were increased (all P<0.05). MDA, IL-6, TNF-α in serum and colon tissues of the UC group were increased compared with the NC group (all P<0.01), and they were decreased after WSP and SASP treatment (all P<0.01). The results of showed that the colon tissue structure was obviously broken and inflammatory infiltration in the UC group, while the H-WSP group and the SASP group significantly improved the colon tissue and alleviated inflammatory infiltration. The expression of TRPV1 in colon tissues in the UC group was increased compared with the NC group (all P<0.01), and it was decreased after WSP and SASP treatment.@*CONCLUSIONS@#WSP can alleviate the inflammatory state of ulcerative colitis induced by DSS, which might be related to the inhibition of inflammatory factors release, and down-regulation or desensitization of TRPV1.

Traditional Chinese Medicine Intervenes in Atherosclerosis by Regulating TLR/NLRP3 Pathway via TRPV1/TRPA1 / 中国实验方剂学杂志

Atherosclerosis is a chronic inflammatory disease caused by lipid accumulation and vascular endothelial dysfunction. The Toll-like receptor （TLR）/nuclear transcription factor-κB （NF-κB） pathway and the NOD-like receptor protein 3 （NLRP3） inflammasome pathway play a proinflammatory role， while the transient receptor potential vanilloid subtype 1 （TRPV1） and transient receptor potential ankyrin 1 （TRPA1） play a protective role in the occurrence of atherosclerosis. We reviewed the relevant studies published in the last 10 years. The results showed that activation of TRPV1/TRPA1 could activate endothelial-type nitric oxide synthase （eNOS） and inhibit the generation of reactive oxygen species （ROS） and cholesterol crystal （CC） to modulate the TLR/NF-κB and NLRP3 inflammasome pathways， thereby inhibiting TLR/NLRP3-mediated inflammatory response. A variety of compound prescriptions and active components of Chinese medicinal materials can activate TRPV1/TRPA1 or its downstream pathway to regulate the TLR/NLRP3 pathway in atherosclerosis. This paper introduces the mechanisms of compound prescriptions and active components of Chinese medicinal materials in regulating the TLR/NLRP3 pathway via TRPV1/TRPA1 in atherosclerosis. This review provides new ideas for the research on the interactions between Chinese medicines in the treatment of atherosclerosis and provides a new strategy for the clinical treatment of atherosclerosis with traditional Chinese medicine.

Effects of lysophosphatidic acid on ischemia/reperfusion injury and TRPV1 expression in isolated mouse heart / 中国药理学通报

Aim To investigate the effects of lysophosphatidic acid on ischemia / reperfusion injury(IRI)and TRPV1 expression in isolated mouse heart.Methods The IRI model of isolated mouse heart was established by Langendorff device.The hearts in sham group were continuously perfused for 100 min.The hearts in IR group were stabilized for 10 min followed by no perfusion for 30 min and reperfusion for 60 min.Exogenous LPA was added in the K-H solution during IR in IR+LPA group while HA130, an LPA synthesis inhibitor, was intraperitoneally injected before IR in IR+HA130 group.The infarct volume was measured by TTC staining, the determination of LPA and LDH levels in coronary effluent and LPA concentration in serum was measured by ELISA method.Finally, the expression levels of pTRPV1/TRPV1 and Bcl-2/Bax in myocardial tissues were determined by Western blot.Results Compared with sham group, IR caused evident myocardial infarction and increased the levels of LDH and LPA in coronary effluent.The increase of LPA was linearly correlated with myocardial infarction volume.In addition, the protein levels of pTRPV1 and TRPV1 in myocardium increased, while the ratio of Bcl-2/Bax decreased.The myocardial injury in IR+LPA group was aggravated.In contrast, myocardial IRI was reversed in IR+HA130 group.Conclusions Myocardial ischemia-reperfusion induces the release of LPA, which aggravates myocardial post-ischemic injury, while the inhibition of LPA release exerts cardioprotective effects.The underlying mechanisms might be related to the regulation on cardiac TRPV1 expression and apoptotic signals.

Research advances in the mechanism of action of TRPV4 ion channel protein in liver diseases / 临床肝胆病杂志

As a member of the transient receptor potential ion channel family, transient receptor potential vanilloid 4 (TRPV4) is a non-selective cation channel and is widely distributed in a variety of tissues and organs. In recent years, more and more studies have shown that TRPV4 channel proteins are closely associated with liver diseases such as liver fibrosis, liver cancer, and polycystic liver disease. This article analyzes the articles on TRPV4 and liver disease and summarizes the exact signaling pathways and possible potential mechanism between TRPV4 and liver disease, so as to provide new ideas for clinical application and further studies.

Research progress on TRPV3 channel / 药学学报

Transient receptor potential vanilloid 3 (TRPV3) is a non-selective cation channel, located on cell membranes. TRPV3 is extensively expressed in various organs such as skin, brain, dorsal root ganglia, heart and colon. It's reported that TRPV3 involves in many physiological processes including sensation, skin barrier formation, hair growth and vasodilatation, and pathological processes like pruritus, cutaneous inflammatory disease and cancer. TRPV3 can respond to innoxious warm stimulation (≥ 33 ‍℃‍), endogenous substances (e.‍g., farnesylpyrophosphate) and exogenous small molecules (e.g., carvacrol, camphor and 2-APB). Recently, several natural or synthetic small molecules (e.g., osthole, 74a and dyclonine) have been shown to suppress TRPV3 activity, accompanying with therapeutic efficacy in animal models of diseases, which suggests the potential of TRPV3 as drug target. This paper reviews the research progress on the structure, physiological functions, related diseases and modulators of the TRPV3 channel to provide theoretical references for the future study on TRPV3 channel.

Mechanism of Aconiti Kusnezoffii Radix Processed with Chebulae Fructus Against H9c2 Cardiomyocyte Toxicity Based on TRPV1 Channel / 中国实验方剂学杂志

ObjectiveTo explore the role of transient receptor potential vanilloid 1 （TRPV1） channel in reducing cardiomyocyte toxicity of Aconiti Kusnezoffii Radix processed with Chebulae Fructus. MethodH9c2 cardiomyocytes cultured in vitro were used as a model to assess cell viability by methyl thiazolyl tetrazolium （MTT） assay， the expression of TRPV1 mRNA was detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）， and the leakage rate of lactate dehydrogenase （LDH）， the changes of nucleus， reactive oxygen species （ROS）， mitochondrial membrane potential and Ca2+ contents were detected by enzyme linked immunosorbent assay （ELISA）. ResultCompared with the blank group， when the concentration was ≥0.5 g·L-1， the cell viability was significantly decreased （P<0.01）， the leakage rate of LDH， the release of ROS and Ca2+ were increased， the mitochondrial membrane potential was decreased， and the nucleus was pyknosis or even broken in raw Aconiti Kusnezoffii Radix and Aconiti Kusnezoffii Radix processed with Chebulae Fructus groups. When the concentration was ≥0.5 g·L-1， compared with the same mass concentration of raw Aconiti Kusnezoffii Radix group， the cell viability increased significantly （P<0.01）， the leakage rate of LDH， the release of ROS and Ca2+ decreased， the mitochondrial membrane potential increased， and the nuclear morphology improved in Aconiti Kusnezoffii Radix processed with Chebulae Fructus group. Application of the same mass concentration of raw Aconiti Kusnezoffii Radix to H9c2 cardiomyocytes pretreated with the TRPV1 inhibitor BCTC significantly increased cell viability， decreased leakage rate of LDH， ROS and Ca2+ release， increased mitochondrial membrane potential and improved nuclear pyknosis compared with untreated H9c2 cardiomyocytes. Application of the same mass concentration of Aconiti Kusnezoffii Radix processed with Chebulae Fructus to H9c2 cardiomyocytes pretreated with BCTC decreased cell viability， increased LDH leakage rate， ROS and Ca2+ release， reduced mitochondrial membrane potential compared with untreated H9c2 cardiomyocytes. Real-time PCR results showed that both raw Aconiti Kusnezoffii Radix and Chebulae Fructus decoction could increase the expression of TRPV1 mRNA in cardiomyocytes in a concentration dependent manner. ConclusionRaw Aconiti Kusnezoffii Radix can induce cardiomyocyte apoptosis and cardiotoxicity by activating TRPV1 channel， while Aconiti Kusnezoffii Radix processed with Chebulae Fructus can attenuate the toxicity through TRPV1 channel， which may be related to the synergistic effect of acid components in Chebulae Fructus and alkaloids in Aconiti Kusnezoffii Radix on TRPV1 channel.

Low Electrical Resistance Properties of Acupoints: Roles of NOergic Signaling Molecules and Neuropeptides in Skin Electrical Conductance / 中国结合医学杂志

Early studies from several independent laboratories demonstrated that acupoints possess the characteristics of low electrical resistance. New devices are developing to increase the reliability of electrical skin impedance measurements for counteracting the factors including skin dryness, skin thickness, size of the sensing electrode, pressure applied on the electrode, interelectrode distance, room temperature, and humidity. Morphological studies have identified that blood vessels, hair follicles, and nervous components are enhanced in the meridians/acupoints, which represent areas of potentially high neuronal activity. Recent evidence shows that nitric oxide (NO) concentrations are enhanced in skin acupoints/meridians. L-arginine-derived NO synthesis modifies skin norepinephrine (NE) synthesis/release in acupoints/meridians, and NO-NE activations play an important role in mediating the skin conductance responses to electrical stimulation. NOergic signaling molecules interact with gap junction and transient receptor potential vanilloid type-1. Other studies reported that the high conductance at acupoints is a result of the release of the neuropeptides substance P and calcitonin gene-related peptide during neurogenic inflammation in the referred pain area. Pathological body conditions caused considerable changes in skin conductance or impedance at acupoints. Although systematic research with an improved equipment and research design to avoid the influencing factors are requested for a definite answer in this field, the results from anatomical and biochemical studies consistently show that acupoints exist higher levels of nervous components, and NOergic signaling molecules and neuropeptides involved in the skin low resistance at acupoints. The increased interest in the acupoints/meridians has led to an open-minded attitude towards understanding this system, which is fundamental important to establish the valid aspects of scientific basis of Chinese medicine mechanisms and therapies.

ASIC2 Synergizes with TRPV1 in the Mechano-Electrical Transduction of Arterial Baroreceptors / 神经科学通报·英文版

Mechanosensitive ion channels (MSCs) are key molecules in the mechano-electrical transduction of arterial baroreceptors. Among them, acid-sensing ion channel 2 (ASIC2) and transient receptor potential vanilloid subfamily member 1 (TRPV1) have been studied extensively and documented to play important roles. In this study, experiments using aortic arch-aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary, as blocking either abrogated nearly all pressure-dependent neural discharge. However, whether ASIC2 and TRPV1 work in coordination remained unclear. So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV1 only partially blocked these currents. Immunofluorescence staining of aortic arch-aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings, and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors. Moreover, protein modeling analysis, exogenous co-immunoprecipitation assays, and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly. In summary, our research suggests that ASIC2 and TRPV1 form a compact complex and function synergistically in the mechano-electrical transduction of arterial baroreceptors. The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV1.

ASIC2 Synergizes with TRPV1 in the Mechano-Electrical Transduction of Arterial Baroreceptors / 神经科学通报·英文版

Mechanosensitive ion channels (MSCs) are key molecules in the mechano-electrical transduction of arterial baroreceptors. Among them, acid-sensing ion channel 2 (ASIC2) and transient receptor potential vanilloid subfamily member 1 (TRPV1) have been studied extensively and documented to play important roles. In this study, experiments using aortic arch–aortic nerve preparations isolated from rats revealed that both ASIC2 and TRPV1 are functionally necessary, as blocking either abrogated nearly all pressure-dependent neural discharge. However, whether ASIC2 and TRPV1 work in coordination remained unclear. So we carried out cell-attached patch-clamp recordings in HEK293T cells co-expressing ASIC2 and TRPV1 and found that inhibition of ASIC2 completely blocked stretch-activated currents while inhibition of TRPV1 only partially blocked these currents. Immunofluorescence staining of aortic arch–aortic adventitia from rats showed that ASIC2 and TRPV1 are co-localized in the aortic nerve endings, and co-immunoprecipitation assays confirmed that the two proteins form a compact complex in HEK293T cells and in baroreceptors. Moreover, protein modeling analysis, exogenous co-immunoprecipitation assays, and biotin pull-down assays indicated that ASIC2 and TRPV1 interact directly. In summary, our research suggests that ASIC2 and TRPV1 form a compact complex and function synergistically in the mechano-electrical transduction of arterial baroreceptors. The model of synergism between MSCs may have important biological significance beyond ASIC2 and TRPV1.

Capsaicin Induces Apoptosis of Colon Cancer SW480 Cells Through TRPV1 / 中国实验方剂学杂志

Objective:To investigate the effects of capsaicin on colon cancer SW480 cells and the underlying molecular mechanism through the transient receptor potential vanilloid 1（TRPV1）. Method:Capsaicin groups with different concentrations and a blank group were set up. The cell viability was detected by cell counting kit-8 （CCK-8） after SW480 cells were treated with capsaicin（50，100，200，300，400，500，600，800，1 000 μmol·L^-1） for 12，24，and 48 h to select the concentration of capsaicin which can effectively inhibit proliferation. The cell cycle and apoptosis were detected by flow cytometry after SW480 cells were treated with capsaicin （200，400，800 μmol·L^-1） for 24 h. The protein expression levels of TRPV1，p53，p-p53，B-cell lymphoma-2（Bcl-2），Bcl-2-associated X protein（Bax），cleaved cysteinyl aspartate-specific protease-3（cleaved Caspase-3），cleaved Caspase-8，and cleaved poly adenosine diphosphate ribose polymerase （PARP） were detected by Western blot after SW480 cells were treated with capsaicin （200，400 μmol·L^-1） for 24 h．In addition，the apoptosis was detected after SW480 cells were treated with TRPV1 microRNA（mRNA） and capsaicin（200 μmol·L^-1）. Western blot analysis was used to detect the protein expression levels of the above proteins. Result:As compared with the blank group，capsaicin（≥200 μmol·L^-1）significantly inhibited the cell viability of SW480 cells（<italic>P</italic><0.01） in dose- and time-dependent manners. The cell cycle was arrested in G₂/M phase by 200 and 400 μmol·L^-1 capsaicin treatment，and arrested in G₁ phase by 800 μmol·L^-1 capsaicin treatment （<italic>P</italic><0.05）. Flow cytometry showed that capsaicin （200， 400， 800 μmol·L^-1） significantly promoted apoptosis of SW480 cells simultaneously（<italic>P</italic><0.05，<italic>P</italic><0.01）. Western blot showed that capsaicin （200，400 μmol·L^-1） significantly up-regulated the protein levels of apoptosis-related proteins（p53，p-p53，Bax，cleaved Caspase-3，cleaved Caspase-8，and cleaved PARP） （<italic>P</italic><0.05，<italic>P</italic><0.01），and significantly down-regulated Bcl-2（<italic>P</italic><0.01）. In addition，siRNA-mediated knockdown of TRPV1 significantly attenuated capsaicin-induced apoptosis and the protein levels of apoptosis-related proteins in SW480 cells（<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Capsaicin can inhibit cell proliferation，arrest cell cycle，and induce apoptosis of SW480 cells，and the possible mechanism may be related to TRPV1 activation.

Transient receptor potential vanilloid-1 antagonist AMG517 playing a neuroprotective role in cerebral ischemia / reperfusion injury in mice by regulating the release of inflammatory factors / 解剖学报

Objective To investigate the effects of transient receptor potential vanilloid-1 (TRPV1) antagonist AMG517 on cerebral ischemic / reperfusion injury in mice. Methods Forty male C57BL / 6 mice were assigned to the following groups: sham group, vehicle + ischemia / reperfusion group (vehicle), capsaicin + ischemia / reperfusion group (capsaicin), and AMG517 + ischemia / reperfusion group (AMG517) . Ischemic / reperfusion injury was induced by permanent middle cerebral artery occlusion(MCAO) and neurological deficits were evaluated 72 hours after MCAO. Then, infarct volume, brain edema, mRNA expression of TRPV1 and serum concentrations of tumor necrosis factor α(TNF-α) and interleukin-10 (IL-10) were measured. Results Compared with the vehicle group, AMG517 significantly decreased the infarct volume (P < 0. 01) . Neurobehavioral score significantly decreased following administration of AMG517 (P < 0. 01) 72 hours after MCAO. Compared with the sham group, the mRNA expression of TRPV1 significantly increased in vehicle group (P < 0. 01) . AMG517 significantly increased the anti-inflammatory cytokine IL-10 and decreased the inflammatory cytokine TNF-α (P<0. 05) . Conclusion AMG517 can improve ischemia / reperfusion injury in mice and may play a neuroprotective effect by alleviating inflammation.

Effect of small dose capsaicin for treatment of pulmonary fibrosis in mice and its mechanism / 中国应用生理学杂志

To observe whether the mechanism of small dose capsaicin (Cap) against pulmonary fibrosis in mouse is mediated by agitating transient receptor potential vanilloid 1 (TRPV1). Methods: A total of 60 BALB/c mice were randomly divided into control (CON) group, bleomycin (BLM)group, Cap (0.5, 1,2 mg/kg) groups and Cap (2 mg/kg) plus SB-452533 (2.5 mg/kg) group. C57BL/6 mice were intratracheally injected with 3.5 mg/kg BLM to induce pulmonary fibrosis model. Animals for drugs treatment received daily drug via subcutaneous injection for 21 days. The morphological changes and collagen deposition in lung tissues were analysed by HE staining, Masson staining and immunohistochemistry. The concentration of calcitonin gene-related peptide (CGRP) in plasma was determined by ELISA. The mRNA and (or) proteins levels of α-CGRP, β-CGRP, collagen I, collagen III, E-Cadherin, zonula occludens-1 (ZO-1), vimentin, alpha smooth muscle actin (α-SMA), TRPV1, p-ERK1/2 and eukaryotic initiation factor 3a (eIF3a) were detected by qPCR and (or) Western blot. Compared with the BLM group, small dose Cap significantly reduced bleomycin-induced pulmonary fibrosis in mice and obviously reversed alveolar epithelial cells epithelial-mesenchymal transition (EMT) (the expression of E-cadherin and ZO-1 were increased(P＜0.05 or P＜0.01)and the expression of α-SMA and Vimentin were decreased (P＜0.05 or P＜0.01) after drugs treatment for 21 day, concomitantly with the increase the expressions of TRPV1 and CGRP (P＜0.05 or P＜0.01), and inhibiting ERK1/2 phosphorylation and eIF3a expression (P＜0.05 or P＜0.01). These effects of small dose Cap were abolished in the presence of TRPV1 receptor antagonist SB-452533. The results suggest that small dose Cap can reverse alveolar epithelial cells EMT and alleviate bleomycin-induced pulmonary fibrosis in mice by inhibiting ERK1/2/eIF3asignaling pathway, which is related to agitating TRPV1 receptor and releasing of CGRP.

Effect of Zuoguiwan on Expression of Ca2+ Transport Pathway-related Protein in Ovariectomized Rats / 中国实验方剂学杂志

Objective::To explore the effect of Zuoguiwan on the bone mineral density (BMD) and the expressions of Ca2+ transport-associated protein in ovariectomized rats. Method::The 48 female SD rats were randomly divided into six groups: normal group, model group, sham operation group, estrogen group(0.167 mg·kg-1) and low and high-dose Zuoguiwan groups(9.6, 38.4 g·kg-1), with 10 rats in each group. Except for the sham-operated group, the ovariectomized rats in the other groups received the bilateral ovariectomy. Therapeutic intervention was given in each group for 3 months after the establishment of the model. After 12 weeks, BMD was measured using dualenergy X-ray absorptiometry. Tartrated presistant acid phosphatse(TRACP) and serum calcium were detected by biochemical kits.Protein expression in Ca2+ transport (Bone tissue) was detected by Western blot. Result::Compared with the normal group, the serum calcium of the model group was decreased(P<0.01). Compared with the normal group, BMD of the model group was decreased (P<0.01). The serum calcium of rats in high-dose group and western medicine group was higher than that of model group(P<0.01). BMD in model group was lower than that of Zuoguiwan groups and estrogen group(P<0.05). There was no significant difference in TRACP among the groups. Nilestriol and Zuoguiwan can down-regulate the expressions of TRPV5, NCX1, CaBP-D28K and PMCA1b in bone tissue of castrated rats(P<0.05, P<0.01). Conclusion::Zuoguiwan can down-regulate the expressions of Ca2+ transport-associated proteins (Bone tissues) in rat osteoclasts, with an efficacy on osteoporosis.

Effect of Houpu Mahuangtang on Airway Inflammation and Expression of TRPA1, TRPV1 mRNA and Protein in Asthmatic Mice / 中国实验方剂学杂志

<b>Objective::To investigate the effect of Houpu Mahuangtang on airway inflammation and expressions of gene and proteins of Transient receptor potential ankyrin 1, vanilloid 1 (TRPA1, TRPV1) in asthmatic mice. <b>Method::Sixty female Balb/c mice were randomly divided into six groups: control group, model group, low, medium and high-dose Houpu Mahuangtang groups (7, 14, 28 g·kg^-1) and dexamethasone group (0.002 4 g·kg^-1), with 10 mice in each group. A mouse model of asthma was replicated by sensitizing and challenging with ovalbumin. The changes of enhanced pause (Penh) following acetylcholine chloride (ACh) inhalation were detected. The pathological changes of the lung tissues were observed. The number of eosinophils (EOS) in peripheral blood and the percentage of EOS in bronchoalveolar lavage fluid (BALF) were detected. Interleukin (IL)-4, IL-13, prostaglandin D₂ (PGD₂) and substance P (SP) were detected by enzyme-linked immuno sorbent assay (ELISA). The expressions of TRPA1 and TRPV1 gene and protein in lung tissues were detected by Quantitative Real-time polymerase chain reaction (Real-time PCR) and Western blot. <b>Result::Compared with control group, mice of model group showed significantly increased in Penh following ACh inhalation (<italic>P</italic><0.05, <italic>P</italic><0.01), EOS in blood and the percentage of EOS in BALF (<italic>P</italic><0.01). Histopathological changes in lungs showed inflammatory cell infiltration and bronchial mucosa damage. The levels of IL-4, IL-13, PGD₂ and SP in BALF and the expressions of TRPA1, TRPV1 mRNA and protein in lung tissues significantly increased (<italic>P</italic><0.05, <italic>P</italic><0.01). Compared with model group, treatment groups had significant effects in decreasing Penh, relieving lung injury, reducing EOS count in blood and the percentage of EOS in BALF (<italic>P</italic><0.05, <italic>P</italic><0.01), reducing IL-4, IL-13, PGD₂ and SP levels in BALF (<italic>P</italic><0.05, <italic>P</italic><0.01), as well as down-regulating TRPA1 and TRPV1 mRNA and protein expressions in lung tissues (<italic>P</italic><0.05, <italic>P</italic><0.01). <b>Conclusion::Houpu Mahuangtang could reduce airway inflammation, airway responsiveness. In addition to the reduction of levels of Th2 related cytokines, the mechanism of Houpu Mahuangtang might be related to the regulation of TRPA1, TRPV1 mRNA and protein expressions, and the decrease of associated neurofactor levels.

Exploration on effect mechanism of Miao medicinal acupuncture therapy in treatment of knee osteoarthritis based on TRPV ion channel / 中国针灸

OBJECTIVE@#To observe the effect of Miao medicinal acupuncture therapy on transient receptor potential vanilloid (TRPV) channel in knee joint synovial tissue of the rabbits with knee osteoarthritis (KOA) model and to explore the mechanism of Miao medicinal acupuncture therapy in treatment of KOA.@*METHODS@#Of 34 New Zealand male rabbits, 6 rabbits were selected randomly as the normal group. KOA model was established in the rest rabbits by injecting a mixture of papain and L-cysteine in right knee joints. The 24 successfully modeled rabbits were randomized into a model group, a Miao medicinal acupuncture therapy group, a dermal needle group and a smearing group, 6 rabbits in each one. In the Miao medicinal acupuncture therapy group, Miao medicinal acupuncture therapy was adopted, in which, the roller type of dermal needle was used on the surface of right knee joint [a rectangle shape formed by "Xuehai" (SP 10), "Liangqiu" (ST 34), "Yanglingquan" (GB 34) and "Yinlingquan" (SP 9)], rolling in a " shape, on which, Miao medicinal solution was smeared in advance. In the dermal needle group, the rolling stimulation was exerted on the right the right knee joint surface with the roller type of dermal needle. In the smearing group, Miao medicinal solution was smeared on the right knee joint surface. The intervention was given once every two days, 3 times weekly and the intervention was exerted consecutively for 4 weeks. Successively, on day 1, 21, 28, 35, 42 and 49 of experiment, paw withdrawal threshold (von Frey threshold) after mechanical stimulation was detected in the rabbits. HE staining was adopted to observe the histomorphological changes of the right knee joint cartilage in the rabbits. ELISA was used to determine the contents of interleukin-1 (IL-1β) and tumor necrosis factor-α (TNF-α) in the right knee synovial fluid. Western blot method and real-time PCR were used to determine the relative expressions of protein and mRNA of TRPV1 and TRPV4 in knee synovial tissue of the rabbits.@*RESULTS@#Compared with the normal group, on day 49 of experiment, von Frey threshold was reduced significantly in the rabbits of the model group (@*CONCLUSION@#Miao medicinal acupuncture therapy plays a role in treatment of KOA probably through inhibiting the expressions of IL-1β and TNF-α of knee synovial fluid and down-regulating the expressions of protein and mRNA of TRPV1 and TRPV4 in knee synovial tissue.