Blockade of transient receptor potential cation channel subfamily V member 1 promotes regeneration after sciatic nerve injury

The transient receptor potential cation channel subfamily V member 1（TRPV1） provides the sensation of pain（nociception）. However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517（300 mg/kg）, a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immunofluorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clusters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve.

Effects of different flow velocities on behavior and TRPA1 expression in the sea cucumber Apostichopus japonicas

A water flow simulation device capable of adjusting flow velocity was designed in flow velocity range of 0–30 cm/s,with which an indoor experiment was conducted to simulate the movement and adhesive behaviors of different-sized Apostichopus japonicus under different flow velocities.Observation showed that,in slow flow(~5 cm/s),A.japonicus moved more distance than in still water,and hardly moved in the riptide(~30 cm/s);and the adhesive capacity of A.japonicus was related to the flow velocity and attachment time.A.japonicus were able to attach to the bottom after any attachment time in the slow flow,after 10 s in the medium flow(~15 cm/s),and after 60 s in the riptide(~30 cm/s).In addition,larger A.japonicus were stronger with adhesive ability than smaller ones.The transcriptome data showed that the expression of transient receptor potential cation channel subfamily A,member 1(TRPA1)in the tube feet was increased significantly in a flowing water,but those in the tentacles and tube feet were not significantly changed.Fluorescence in-situ hybridization results showed that TRPA1 was expressed around the watervascular of tentacles,tube feet,body wall,and spines.Therefore,tube feet were important for sea cucumbers to keep themselves stable in relatively swift flow with adhesion ability.

Polymorphisms of AZIN1 rs2679757 and TRPM5 rs886277 are Associated with Cirrhosis Risk in Chinese Patients with Chronic Hepatitis B

Objective Genome-wide association studies(GWAS)have linked many single nucleotide polymorphisms(SNPs)to the outcomes of a variety of liver diseases.The aim of the present study was to evaluate the association of several candidate SNPs with the risk and severity of cirrhosis due to chronic hepatitis B in a Chinese population.Methods A total of 714 Chinese participants with persistent HBV infection were studied.Patients were divided into cirrhotic(n=429)and non-cirrhotic(n=285)groups based on clinical and pathological evidence.The progression rate and severity of liver cirrhosis were evaluated with an arbitrary t-score system.Genotypes of six SNPs in five candidate genes were detected with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS).The genotypic distributions of the SNPs were compared between the age-matched cirrhotic and non-cirrhotic subjects.The association between the risk of SNPs and the severity and progression rate of cirrhosis was further analyzed.Results Rs2679757 polymorphism of the antizyme inhibitor 1(AZIN1)gene and Rs886277 in the transient receptor potential cation channel subfamily M,member 5 gene(TRPM5)were found to be associated with cirrhosis risk in CHB.They were also correlated with the overall severity and progression rate of cirrhosis.Genotype frequencies of other SNPs were not different between the cirrhosis and non-cirrhosis groups.Conclusions AZIN1 rs2679757 and TRPM5 rs886277 are associated with the risk and the progression rate of HBV-related liver fibrosis in Chinese patients.The emerging SNPs associated with cirrhosis prognosis warrant further clinical validation in other CHB cohorts or ethnic groups,and merit mechanistic studies to reveal their roles in fibrosis progression.

Murine calcium-activated chloride channel family member 3 induces asthmatic airway inflammation independently of allergen exposure

Background Expression of murine calcium-activated chloride channel family member 3 （mCLCA3） has been reported to be increased in the airway epithelium of asthmatic mice challenged with ovalbumin （OVA）. However, its role in asthmatic airway inflammation under no OVA exposure has not yet been clarified. Methods mCLCA3 plasmids were transfected into the airways of normal BALB/c mice. mCLCA3 expression and airway inflammation in mouse lung tissue were evaluated. Cell differentials and cytokines in bronchoalveolar lavage fluid （BALF） were analyzed. The expression of mCLCA3 protein and mucus protein mucin-5 subtype AC （MUC5AC） were analyzed by Western blotting. The mRNA levels of mCLCA3, MUC5AC and interleukin-13 （IL-13） were determined quantitatively. Results mCLCA3 expression was not detected in the control group while strong immunoreactivity was detected in the OVA and mCLCA3 plasmid groups, and was strictly localized to the airway epithelium. The numbers of inflammatory cells in lung tissue and BALF were increased in both mCLCA3 plasmid and OVA groups. The protein and mRNA levels of mCLCA3 and MUC5AC in the lung tissue were significantly increased in the mCLCA3 plasmid and OVA groups compared to the control group. The level of IL-13, but not IL-4, IL-5, IFN-y, CCL2, CCL5 or CCL11, was significantly increased compared with control group in BALF in the mCLCA3 plasmid and OVA groups. The level of IL-13 in the BALF in the mCLCA3 plasmid group was much higher than that in the OVA group （P 〈0.05）. The level of mCLCA3 mRNA in lung tissue was positively correlated with the levels of MUC5AC mRNA in lung tissue, IL-13 mRNA in lung tissue, the number of eosinophils in BALF, and the content of IL-13 protein in BALE The level of IL-13 mRNA in lung tissue was positively correlated with the number of eosinophils in BALF and the level of MUC5AC mRNA in lung tissue. Conclusion These findings suggest that increased expression of a single-gene, mCLCA3, could simulate an asthma attack, and its mechanism may involve mCLCA3 overexpression up-regulating IL-13 expression.

KCNH2 regulates the growth and metastasis of pancreatic cancer

Objective:Due to the characteristics of insidious onset and early metastasis of pancreatic cancer(PC),patients are often diag-nosed at an advanced stage and often delayed in completing surgical resection timely,resulting in poor prognosis.Therefore,this study aims to explore the expression of potassium voltage-gated channel subfamily H member 2(KCNH2)in PC and its relation-ship with clinicopathological parameters and the related mechanisms.Methods:GEPIA database and immunohistochemical staining were used to analyze the difference in KCNH2 expression be-tween PC and adjacent tissue in RNA and protein levels.Chi-squared test was used to evaluate the relationship between KCNH2 expression and clinicopathological features.The Cox regression model was used for multivariate analysis and univariate analysis.Histological diagnosis was performed according to World Health Organization(WHO)criteria to evaluate the relationship between KCNH2 expression and clinicopathological features.Results:KCNH2 expression was upregulated in PC compared with normal pancreatic tissue.In addition,the knockdown of KCNH2 inhibits PC cell proliferation,migration,invasion,and epithelial-mesenchymal transformation and promotes their apopto-sis.In addition,clinical data showed that the abnormal expression of KCNH2 in PC was related to the tumor stage.Patients with high expression of KCNH2 had a poor prognosis.Conclusions:KCNH2 is expected to be a novel targeted molecule in treating PC.