Polymodal Transient Receptor Potential Vanilloid (TRPV) Ion Channels in Chondrogenic Cells

Abstract

Mature and developing chondrocytes exist in a microenvironment where mechanical load, changes of temperature, osmolarity and acidic pH may influence cellular metabolism. Polymodal Transient Receptor Potential Vanilloid (TRPV) receptors are environmental sensors mediating responses through activation of linked intracellular signalling pathways. In chondrogenic high density cultures established from limb buds of chicken and mouse embryos, we identified TRPV1, TRPV2, TRPV3, TRPV4 and TRPV6 mRNA expression with RT-PCR. In both cultures, a switch in the expression pattern of TRPVs was observed during cartilage formation. The inhibition of TRPVs with the non-selective calcium channel blocker ruthenium red diminished chondrogenesis and caused significant inhibition of proliferation. Incubating cell cultures at 41 °C elevated the expression of TRPV1, and increased cartilage matrix production. When chondrogenic cells were exposed to mechanical load at the time of their differentiation into matrix producing chondrocytes, we detected increased mRNA levels of TRPV3. Our results demonstrate that developing chondrocytes express a full palette of TRPV channels and the switch in the expression pattern suggests differentiation stage-dependent roles of TRPVs during cartilage formation. As TRPV1 and TRPV3 expression was altered by thermal and mechanical stimuli, respectively, these are candidate channels that contribute to the transduction of environmental stimuli in chondrogenic cells.

Activation of TRPV3 Regulates Inflammatory Actions of Human Epidermal Keratinocytes

“…In support of these findings, we also identified TRPV3 expression in human epidermis and on cultured primary human keratinocytes at both the mRNA and protein levels (Figure 1). Our results further show that TRPV3 is functional on keratinocytes and acts as a calcium-permeable channel (Figure 2), similarly to results on other cells types (Borbíró et al, 2011;Lee et al, 2016;Morgan et al, 2013;Pires et al, 2015;Somogyi et al, 2015) and in murine keratinocytes (Chung et al, 2004b;Huang et al, 2008;Mandadi et al, 2009). Because the calcium increase was abrogated in the absence of extracellular calcium, it is likely that TRPV3 acts as a membrane channel.…”

Analgesic and Anti-Inflammatory Effects of the Novel Semicarbazide-Sensitive Amine-Oxidase Inhibitor SzV-1287 in Chronic Arthritis Models of the Mouse

“…The cartilage damaging action of LJP-1207 in the chronically inflamed joint is not likely to be due to its SSAO inhibitory effect, since a very recently published paper reports that SSAO inhibition delayed the chondrocyte differentiation without any alteration of cell viability in vitro 38; this might be related to some other mechanisms due to its different structure. The unique features of SzV-1287 compared to other SSAO inhibitors are its COX inhibitory action, without ulcerogenic effects25, and potent dual antagonistic property at the TRPV1/TRPA1 ion channels localised on peptidergic sensory nerves39, inflammatory cells40, and chondrocytes4142. The importance of TRPV1/TRPA1-dependent neurogenic inflammatory mechanisms in RA has been extensively investigated and received a great attention434445.…”

Differential expression and localization of thermosensitive Transient Receptor Potential Vanilloid (TRPV) channels in the mature sperm of white pekin duck (Anas platyrhynchos)

“…Notably, the difference in band size and predicted molecular weight of the TRPV channels could arise from species or individual specific differences, post-translational modifications, partial degradation of the proteins or presence of splice variants [28]. However, we have consistently obtained prominent bands near the predicted molecular weight for all channels tested.…”