The Effects of Lung Ischaemia/Reperfusion on TRPM Gene Expression

ABSTRACT Objective: Transient receptor potential melastatin (TRPM) are integral membrane proteins that have broad range of cellular functions. Roles of TRPM2, TRPM3, TRPM4 and TRPM7 among these channels are very important, and their roles in lung ischaemia/reperfusion injury have not been evaluated yet. The aim of this study is to investigate the contribution of these genes in lung ischaemia/reperfusion injury and evaluate histopathology of tissues. Methods: A total of 40 Wistar albino rats were enrolled for the study. Ischaemia was performed by the application of an atramvatic clamp to pulmonary artery. Gene expressions were determined by the semi-quantitative reverse transcription-polymerase chain reaction method. Histopatholical evaluations were held by a standard haematoxyline-eosin staining. Results: The major histopathological tissue damage was observed in ischaemia performed groups, and expression of TRPM channels was found to be obviously downregulated. Substantial changes were determined between TRPM2, TRPM3, TRPM4 and TRPM7 and lung ischaemia/reperfusion injury. In particular, expression of TRPM2 and TRPM7 was reversibly downregulated in ischaemia. Yet, the expression of TRPM3 and TRPM4 was irreversibly down-regulated after ischaemia. Conclusion: Consequently, these results indicate that TRPM family of cation channels may have significant roles in the lung ischaemia/reperfusion injury.

Comparing the effects of fluticasone, anti-IgE and anti-TNF treatments in a chronic asthma model.

BACKGROUND: Corticosteroids are used in the treatment of asthma. The aim of this study was to determine the efficacy of anti-IgE and anti-TNF alpha as asthma treatments. METHODS: A mouse model of chronic asthma was developed. The fluticasone group was exposed to fluticasone and the anti-IgE and anti-TNF groups were administered anti-IgE or anti-TNF. IL-4, and IgE levels were measured, and histological analysis, pathological analysis and miRNA-126, miRNA-133a analyses were applied. RESULTS: The cell concentration in the BAL fluid decreased in all the treatment groups. The rate of perivascular and peribronchial cell infiltration decreased in the lung in the high-dose anti-IgE and anti-TNF groups. Smooth muscle thickness decreased in the lung tissue in the low-dose anti-IgE and anti-TNF groups. Bronchial wall thickness decreased in the lung tissue in the fluticasone+anti-IgE group. The IL-4 level in BAL fluid decreased in the high-dose anti-IgE, fluticasone+anti-IgE and anti-TNF groups. IgE levels increased in the BAL fluid in the high-dose anti-IgE and anti-TNF groups. The lymphocyte level increased in the BAL fluid in the high-dose anti-IgE group. The macrophage level decreased in the BAL fluid in the anti-TNF group. The relative expression of miRNA-126 increased in all groups. The relative expression of miRNA-133a decreased in the placebo and fluticasone groups. The relative expression of miRNA-133a increased in the low-dose anti-IgE, high-dose anti-IgE, fluticasone+anti-IgE and anti-TNF groups. CONCLUSIONS: The results showed that anti-IgE is successful as a treatment. Fluticasone+anti-IgE and anti-TNF were seen to be superior to other therapeutic modalities when used for prophylaxis.

TRP genes family expression in colorectal cancer.

UNLABELLED: Colorectal cancer (CRC) is the most common cancer of the gastrointestinal tract. Different factors are responsible for the development of CRC. Transient Receptor Potential (TRP) which is an important component of calcium channel is associated with several pathological conditions like cancer, neurodegenerative and cardiovascular diseases. Thirty members of the family of TRP ion channel in mammals have been determined till now. The aim of this study is to investigate TRPM, TRPV and TRPC gene expression levels in tumor tissues of CRC patients and to analyze the relationship of expression in tumor tissue of CRC with other known prognostic factors. MATERIAL AND METHODS: In this study, 93 CRC patients were included. The level of TRP gene expression in paraffin blocks of normal and cancerous colorectal tissue samples were studied at the level of mRNA with Real-time PCR. RESULTS: The mRNA expression level of TRPV3, TRPV4, TRPV5, TRPM4 and TRPC6 genes in 37 female and 56 male patients diagnosed with CRC was revealed lower in tumor tissue as compared to normal tissue (p < 0.05). No statistically significant differences of mRNA expression levels of other TRP genes were found. CONCLUSIONS: TRP gene family like TRPV3, TRPV4, TRPV5, TRPM4 and TRPC6 may be thought as potential genes contributing to tumorigenesis as their expression decreases in CRC as compared to normal tissues.

Role of the transient receptor potential (TRP) channel gene expressions and TRP melastatin (TRPM) channel gene polymorphisms in obesity-related metabolic syndrome.

OBJECTIVE: Metabolic syndrome (MetS) is correlated with increased cardiovascular risk and characterized by several factors, including visceral obesity, hypertension, dyslipidemia, and insulin resistance. The etiology of MetS is complex, and can be influenced by genetic susceptibility. The aim of this study was to investigate a possible association of transient receptor potential (TRP) channels gene expressions and TRP melastatin (TRPM) gene polymorphisms with MetS in a Turkish population. PATIENTS AND METHODS: A total of 142 patients with obesity-related MetS and 166 healthy controls with similar age and sex were enrolled to this study. For polymorphism studies, genomic DNA from the participants was analyzed by a BioMark 96.96 dynamic array system (Fluidigm, South San Francisco, CA, USA). For gene expression studies, mRNA from blood samples was extracted, and real time polymerase chain reaction on the BioMark HD system was performed. RESULTS: There was an increase in A allele (64.6% in patients vs. 49.5% in controls) and decrease in G allele frequencies (35.4% in patients vs. 50.5% in control, p = 0.0019) of the TRPM5 gene rs4929982 (Arg578Gln) polymorphism. We also observed that the distribution of genotype and allele frequencies of the TRPM8 gene rs12472151 in MetS patients were significantly different from controls (p < 0.0001). Although there were marked decreases in TRPC1, TRPC3, TRPM2, TRPM5, TRPV4, TRPV5, TRPV6, MCOLN2 (TRPML2), and MCOLN3 (TRPML3) gene expressions, an augmentation was noted in TRPC6 gene expression. CONCLUSIONS: Genetic polymorphisms in TRPM5 and TRPM8 genes may modify individual susceptibility to MetS in the Turkish population. This study also revealed that there is a significant relationship between TRP channels gene expressions and MetS.

Association of Rho/Rho-kinase gene polymorphisms and expressions with obesity-related metabolic syndrome.

OBJECTIVE: The metabolic syndrome (MetS) is a common multicomponent condition including abdominal obesity, dyslipidemia, hypertension and hyperglycemia. The aim of this study was to investigate the associations of Rho GTPase and Rho-kinase (ROCK) gene polymorphisms and expressions with MetS in a Turkish population. PATIENTS AND METHODS: A total of 141 obese MetS patients and 163 healthy controls with similar age and sex were included to this study. Polymorphisms were analyzed in genomic DNA using a BioMark 96.96 dynamic array system. mRNA from blood samples was extracted, and real-time polymerase chain reaction was performed for gene expressions. RESULTS: We observed that genotype (CC, 18.1%; CA, 13.4%, and AA, 68.5%) and allele (C, 24.8%; A, 75.2%) frequencies for the rs35996865 polymorphism of the ROCK1 gene in patients were markedly different from controls (CC, 84.2%; CA, 2.9%, and AA, 12.9%; C, 85.6%; A, 14.4%, p < 0.0001). In the rs2230774 (Thr431Asn) polymorphism of the ROCK2 gene, there were increases in the CC genotype (16.5%) and C allele frequencies (20.4%) in MetS patients when compared with the control group (CC, 6.0%, p = 0.0009, and C, 6.7%, p < 0.0001). However, no associations with the other 18 polymorphisms studied were found. Although there were an increase in peripheral blood mRNA RhoH expressions, marked decreases in RhoC, RhoBTB1, RhoV, Rnd1, and CDC42 gene expressions were noted in MetS patients. CONCLUSIONS: This is the first study to provide evidence that ROCK gene polymorphisms and gene expressions of the Rho GTPase proteins may modify individual susceptibility to MetS in the Turkish population.

The role of bronchial epithelial cell apoptosis in the pathogenesis of COPD.

There is an increased airway inflammation in the pathogenesis of chronic obstructive pulmonary disease (COPD), and it has been suggested that there may also be problem in the apoptosis and renewal of cells. However, there are limited human airway cell studies, in particular those from larger airways such as bronchi. We cultured primary human bronchial epithelial cells (HBECs) from bronchial explants of smokers (n = 6) without COPD and smokers with COPD (n = 8). Apoptosis was studied by fluorescence activated cell sorting. qRT-PCR was used to assess mRNA expression for proteins involving apoptosis including p21(CIP1/WAF1), p53, caspase-8 and caspase-9. Although there was no difference in the rate of viable cells between cells from smokers and COPDs, the level of early apoptotic cells was significantly increased in COPD cells [mean ± standard error of mean (SEM) = 4.86 ± 3.2 %, p = 0.015] as compared to smokers (mean ± SEM = 2.71 ± 1.62 %). In contrast, the rate of late apoptotic cells was significantly decreased in COPD cells (mean ± SEM = 9.82 ± 5.71 %) comparing to smokers (mean ± SEM = 15.21 ± 5.08 %, p = 0.003). Although expression of mRNA for p21(CIP1/WAF1) and caspase-9 was similar in both groups, p53 and caspase-8 mRNA expression was significantly greater in COPD cells. These findings suggest that HBEC apoptosis is increased in COPD, and that this involves p53 and caspase-8 pathways.

Is there any association between childhood cardiac septal defects and ROCK2 gene polymorphism?

Rho/Rho-kinase pathway plays a critical role in the regulation of cellular functions such as proliferation and migration. One of the possible theories of the development of ventricular septal defects is cell migration disorder. The aim of this study was to analyze the genotype distributions and allele frequencies for the ROCK2 gene Thr431Asn polymorphisms in the development of cardiac septal defects in a Turkish population. In this case-control study, 300 patients with cardiac defects (150 patients with ventricular and 150 patients with atrial septal defects) and control group (150 healthy control subjects) were investigated. A single-nucleotide polymorphism in ROCK2 gene Thr431Asn was analyzed by real-time PCR using a Light-Cycler. Neither genotype distributions nor the allele frequencies for the Thr431Asn polymorphism showed a significant difference between the groups. These results suggest that there is no association of the ROCK2 gene Thr431Asn polymorphism with the development of cardiac septal defects in pediatric patients.

Effect of verapamil and lidocaine on TRPM and NaV1.9 gene expressions in renal ischemia-reperfusion.

BACKGROUND: To determine effects on calcium and sodium channels of Ca(2+) and Na(+) channel blockers in the present study, expression levels of TRPM1, TRPM2, TRPM3, TRPM4, TRPM5, TRPM6, TRPM7, TRPM8, and NaV1.9 genes were evaluated in kidney tissues after induced ischemia-reperfusion. MATERIAL AND METHODS: Forty albino Wistar male rats were equally divided into 4 groups as follows: group I: control group (n = 10), group II: ischemia group (60 minutes of ischemia + 48 hours of reperfusion; n = 10), group III: ischemia (60 minutes of ischemia + 48 hours of reperfusion) + calcium channel blocker (n = 8), group IV: ischemia (60 minutes of ischemia + 48 hours of reperfusion) + sodium channel blocker (n = 8). RESULTS: When compared to ischemia group expression levels of TRPM2, TRPM4, TRPM6, and NaV1.9 in Ca(2+) and Na(+) channel blocker groups were increased, whereas that of TRPM7 was decreased. However, expression levels of TRPM1, TRPM3, TRPM5, and TRPM8 were not determined in kidney tissue. Histologically, the Ca(2+) channel blocker verapamil and the Na(+) channel blocker lidocaine inhibited the cell death in kidney tissue compared to control. CONCLUSION: Our study suggested that verapamil and lidocaine significantly reduce the degree of ischemia-reperfusion injury due to effects to TRPM and Nav1.9 genes.