HC067047 as a potent TRPV4 inhibitor repairs endotoxemia colonic injury

Transient receptor potential vanilloid 4 blockage attenuates pyroptosis in hippocampus of mice following pilocarpine‑induced status epilepticus

Pyroptosis contributes to the neuronal damage that occurs during epilepsy. Calcium-activated neutral protease (calpain) dissociates cysteinyl aspartate specific proteinase-1 (caspase-1, cas-1) from the cytoskeleton, and the activated cas-1 is responsible for the production of N-terminus of gasdermin D (N-GSDMD), the final executor of pyroptosis. Blocking transient receptor potential vanilloid 4 (TRPV4) can reduce neuronal injury in temporal lobe epilepsy (TLE) model mice. This study investigated the role of TRPV4 in pyroptosis during TLE. In the hippocampus of pilocarpine-induced status epilepticus (PISE) mice, the ratio of inactive calpain 1 protein level to its total protein level (inactive/total calpain 1) significantly decreased, while the ratio of inactive calpain 2 protein level to its total protein level remained unchanged. The protein levels of NLRP3, cleaved cas-1 (c-cas-1), interleukin (IL)-1β, and N-GSDMD increased, with more GSDMD-immunofluorescence-positive (GSDMD+) cells and fewer surviving pyramidal neurons observed in the hippocampus of PISE mice. Calpain inhibition with MDL-28170 reversed these changes, except for the elevated NLRP3 levels. Inhibitors targeting NLRP3 (MCC950) and cas-1 (Ac-YVAD-cmk) blocked the increase in c-cas-1, IL-1β, and N-GSDMD levels in the hippocampus of PISE mice. TRPV4 inhibition via HC-067047 increased the inactive/total calpain 1 ratio, decreased NLRP3, c-cas-1, IL-1β, and N-GSDMD protein levels, reduced GSDMD+ cells number, and improved pyramidal neuron survival in the hippocampus of PISE mice. Conversely, TRPV4 activation with GSK1016790A decreased the inactive/total calpain 1 ratio, elevated NLRP3, c-cas-1, IL-1β, and N-GSDMD levels, and increased GSDMD+ cells number in the hippocampus. In the hippocampus of GSK1016790A-injected mice, the inactive/total calpain 1 ratio was increased by MDL-28170, and c-cas-1, IL-1β, and N-GSDMD protein levels were markedly attenuated by MDL-28170, MCC950, and Ac-YVAD-cmk, respectively. In conclusion, TRPV4 inhibition mitigates pyroptosis in PISE mice by downregulating the calpain 1-NLRP3/cas-1-GSDMD pathway, ultimately reducing neuronal damage.

The Role of the TRPV4 Channel in Intestinal Physiology and Pathology

The transient receptor potential vanilloid 4 channel (TRPV4) is an important member of the TRP superfamily of cation channels. The channel can be activated by different physical and chemical stimuli, such as heat, osmotic, and mechanical stress. It regulates the release of nociceptive peptides (substance P and calcitonin gene-related peptide), and mediates neurogenic inflammation, which indicates the involvement of TRPV4 as a nociceptor. Previous studies show that TRPV4 regulates the contraction of intestinal smooth muscle, mucosal barrier permeability, intestinal ion transport, activation of submucosal enteric neurons, and generation of immune cells. TRPV4 is involved in various pathophysiological activities, and altered TRPV4 expression has been detected in some intestinal diseases (IBD, IBS, intestinal tumors, etc). Evidence indicates that TRPV4 plays a noxious role in intestinal barrier function when the intestine is damaged. This review focuses on the role of the TRPV4 channel in the physiological and pathological functions of the intestine, and evaluates the potential clinical significance to target TRPV4 channel in the treatment of intestinal diseases.

Gut mechanoimmunology: Shaping immune response through physical cues

The gut immune system embodies a complex interplay between the gut mucosal barrier, the host's immune cells, and gut microbiota. These components exist within a dynamic environment characterized by a variety of physical cues, e.g., compression, tension, shear stress, stiffness, and viscoelasticity. The physical cues can be modified under specific pathological conditions. Given their dynamic nature, comprehending the specific effects of these physical cues on the gut immune system is critical for pathological and therapeutic studies of intestinal immune-related diseases. This review aims to discuss how physical cues influence gut immunology by affecting the gut mucosal barrier, host immune cells, and gut microbiota, defining this concept as gut mechanoimmunology. This review seeks to highlight that an enhanced understanding of gut mechanoimmunology carries therapeutic implications, not only for intestinal diseases but also for extraintestinal diseases.

PERK inhibitor (ISRIB) improves depression-like behavior by inhibitions of HPA-axis over-activation in mice exposed to chronic restraint stress

Stressful life event is closely associated with depression, thus strategies that blunt or prevent the negative effect stress on the brain might benefits for the treatment of depression. Although previous study showed the role of protein kinase R (PKR)-like ER kinase (PERK) in inflammation related depression, its involvement in the neuropathology of chronic stress induced depression is still unknown. We tried to explore whether block the PERK pathway would alleviate the animals' depression-like behavior induced by chronic restraint stress (CRS) and investigate the underlying mechanism. The CRS-exposed mice exhibited depression-like behavior, including anhedonia in the sucrose preference test (SPT), and increased immobility time in tail suspension test (TST) and forced swim test (FST). ISRIB administration for 2 weeks significantly improved the depression-like behavior in male mice exposed to CRS, which was manifested by markedly increasing the sucrose preference and reducing the immobility time in the FST and TST. However, we observed that exposure to the same dose of ISRIB in CRS female mice only showed improved anhedonia-like deficits,leaving unaltered improvement in the FST and TST. Mechanically, we found that ISRIB reversed the hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, indicating decreased levels of serum corticosterone, reduced hippocampal glucocorticoidreceptor (GR) expression and expression of FosB in hypothalamic paraventricularnucleus (PVN), which was accompanied by preserved hippocampal neurogenesis. The present findings further expand the potential role of ER stress in depression and provide important details for a therapeutic path forward for PERK inhibitors in mood disorders.

Transient receptor potential channels' genes forecast cervical cancer outcomes and illuminate its impact on tumor cells

Introduction: In recent years, there has been a strong association between transient receptor potential (TRP) channels and the development of various malignancies, drug resistance, and resistance to radiotherapy. Consequently, we have investigated the relationship between transient receptor potential channels and cervical cancer from multiple angles. Methods: Patients' mRNA expression profiles and gene variants were obtained from the TCGA database. Key genes in transient receptor potential channel prognosis-related genes (TRGs) were screened using the least absolute shrinkage and selection operator (LASSO) regression method, and a risk signature was constructed based on the expression of key genes. Various analyses were performed to evaluate the prognostic significance, biological functions, immune infiltration, and response to immunotherapy based on the risk signature. Results: Our research reveals substantial differences between high and low-risk groups in prognosis, tumor microenvironment, tumor mutational load, immune infiltration, and response to immunotherapy. Patients in the high-risk group exhibited poorer prognosis, lower tumor microenvironment scores and reduced response to immunotherapy while showing increased sensitivity to specific targeted drugs. In vitro experiments further illustrated that inhibiting transient receptor potential channels effectively decreased the proliferation, invasion, and migration of cervical cancer cells. Discussion: This study highlights the significant potential of transient receptor potential channels in cervical cancer, emphasizing their crucial role in prognostic prediction and personalized treatment strategies. The combination of TRP inhibitors with immunotherapy and targeted drugs may offer promise for individuals affected by cervical cancer.

The role of TRPV4 in programmed cell deaths

Programmed cell death is a major life activity of both normal development and disease. Necroptosis is early recognized as a caspase-independent form of programmed cell death followed obviously inflammation. Apoptosis is a gradually recognized mode of cell death that is characterized by a special morphological changes and unique caspase-dependent biological process. Ferroptosis, pyroptosis and autophagy are recently identified non-apoptotic regulated cell death that each has its own characteristics. The transient receptor potential vanilloid 4 (TRPV4) is a kind of nonselective calcium-permeable cation channel, which is received more and more attention in biology studies. It is widely expressed in human tissues and mainly located on the membrane of cells. Several researchers have identified that the influx Ca2+ from TRPV4 acts as a key role in the loss of cells by apoptosis, ferroptosis, necroptosis, pyroptosis and autophagy via mediating endoplasmic reticulum (ER) stress, oxidative stress and inflammation. This effect is bad for the normal function of organs on the one hand, on the other hand, it is benefit for anticancer activities. In this review, we will summarize the current discovery on the role and impact of TRPV4 in these programmed cell death pathological mechanisms to provide a new prospect of gene therapeutic target of related diseases.