Transient Receptor Potential Vanilloid Research Articles

Engineering magnetic nanosystem for TRPV1 and TRPV4 channel activation.

Recently, physical tools for remotely stimulating mechanical force-sensitive and temperature-sensitive proteins to regulate intracellular pathways have opened up novel and exciting avenues for basic research and clinical applications. Among the numerous modes of physical stimulation, magnetic stimulation is significantly attractive for biological applications due to the advantages of depth penetration and spatial-temporally controlled transduction. Herein, the physicochemical parameters (e.g., shape, size, composition) that influence the magnetic properties of magnetic nanosystems as well as the characteristics of transient receptor potential vanilloid-1 (TRPV1) and transient receptor potential vanilloid-4 (TRPV4) channels are systematically summarized, which offer opportunities for magnetic manipulation of cell fate in a precise and effective manner. In addition, representative regulatory applications involving magnetic nanosystem-based TRPV1 and TRPV4 channel activation are highlighted, both at the cellular level and in animal models. Furthermore, perspectives on the further development of this magnetic stimulation mode are commented on, with emphasis on scientific limitations and possible directions for exploitation. This article is categorized under: Diagnostic Tools > Biosensing Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Interrelated involvement of the endocannabinoid/endovanilloid (TRPV1) systems and epigenetic processes in anxiety- and working memory impairment-related behavioural effects of nicotine as a stressor.

The addictive use of nicotine contained in tobacco is associated with stressor-like emotional and cognitive effects such as anxiety and working memory impairment, and the involvement of epigenetic mechanisms such as histone acetylation has recently been reported. Although the precise nature of behavioural plasticity remains unclear, both anxiogenic- and working memory impairment-like effects were observed in the present experimental model of mice treated with repeated subcutaneous nicotine and/or immobilization stress, and these effects were commonly attenuated by the histone deacetylase (HDAC) inhibitors that induce histone acetylation. Such HDAC inhibitor-induced resilience was mimicked by ligands for the endocannabinoid (ECB) system, a neurotransmitter system that is closely associated with nicotine-induced addiction-related behaviours: the anxiogenic-like effects were mitigated by the cannabinoid type 1 (CB1) agonist arachidonylcyclopropylamide (ACPA), whereas the working memory impairment-like effects were mitigated by the CB1 antagonist SR 141716A. Moreover, the effects of the HDAC inhibitors were also mimicked by ligands for the endovanilloid (transient receptor potential vanilloid 1 [TRPV1]) system, a system that shares common characteristics with the ECB system: the anxiogenic-like effects were mitigated by the TRPV1 antagonist capsazepine, whereas the working memory impairment-like effects were mitigated by the TRPV1 agonist olvanil. Notably, the HDAC inhibitor-induced anxiolytic-like effects were attenuated by SR 141716A, which were further counteracted by capsazepine, whereas the working memory improvement-like effects were attenuated by capsazepine, which were further counteracted by SR 141716A. These results suggest the contribution of interrelated control of the ECB/TRPV1 systems and epigenetic processes such as histone acetylation to novel therapeutic approaches.

Gene Expression Level and Immunohistochemical Localization of Cannabinoid and Cannabinoid-Related Receptors in The Small Intestine of Holstein Bulls (Bos Taurus Taurus)

Abstract The gastrointestinal tract plays a crucial role in nutrient absorption, secretion, and motility, ensuring proper digestion and overall homeostasis. Regulation of this complex system involves the coordination of various communication pathways, including neural and humoral mechanisms. One such mechanism is the endocannabinoid system (ECS), a signaling network comprising endogenous cannabinoids, receptors, and enzymes involved in the regulation of physiological processes in mammals and non-mammalian species. While extensive research has been conducted on the ECS in monogastric animals, limited information is available on its presence and distribution in cattle. This study aimed to investigate the distribution and localization patterns of cannabinoid receptors type 1 (CB1R) and type 2 (CB2R) and transient receptor potential vanilloid type 1 (TRPV1) in the bovine small intestine. The study included immunohistochemical analysis of intestinal tissue samples from Polish Holstein-Friesian breed bulls. Gene expression levels of CNR1, CNR2, and TRPV1 genes, encoding CB1R, CB2R, and TRPV1, respectively, were quantified using qPCR analysis. The results showed that all three receptors were expressed in the bovine small intestine, with TRPV1 exhibiting a significant upregulation in the jejunum compared to the duodenum and ileum. Immunoreactivity for CB1R and CB2R was predominantly observed in neurons of the enteric plexuses, while TRPV1 immunolabeling was detected in both enteric neurons and duodenal Brunner’s glands. These findings may establish an anatomical foundation for further investigations, lending support to the potential therapeutic efficacy of cannabinoid receptor agonists in alleviating gastrointestinal motility disorders associated with bovine enteropathies and optimizing milk production in dairy cattle.

TRPV1/cPLA2/AA pathway contributes to ferroptosis-mediated acute liver injury in heatstroke

With the increasing frequency of global heatwaves, the incidence of heatstroke (HS) is significantly rising. The liver plays a crucial role in metabolism and is an organ highly sensitive to temperature. Acute liver injury (ALI) frequently occurs in patients with HS, yet the exact mechanisms driving ALI in HS are still unknown. In this basic study, we investigated the specific molecular mechanisms by which cytosolic phospholipase A2 (cPLA2) mediates ferroptosis, contributing to the development of ALI following HS. We utilized a mouse model of HS and divided the mice into healthy control and HS groups for a series of experiments. Firstly, we assessed oxidative damage markers in tissues and cells, as well as ferroptosis biomarkers. Additionally, we conducted a non-targeted metabolomics analysis to validate the role of key enzymes in metabolism and the ferroptosis pathway. Our results indicated that ferroptosis contributed to the progression of ALI after HS. Administering the ferroptosis inhibitor liproxstatin-1 (10 mg/kg) post-HS onset significantly inhibits HS-induced ALI progression. Mechanistically, heatstroke triggered cPLA2 activation and increased the levels of its metabolic product, arachidonic acid, thereby further promoted the occurrence of ferroptosis. Furthermore, heatstroke mediated cPLA2 activation might involve enhancing transient receptor potential vanilloid subtype 1 (TRPV1) receptor function. Overall, these results highlighted the critical role that cPLA2-mediated ferroptosis plays in the development of ALI following HS, indicating that inhibiting cPLA2 may present a novel therapeutic approach to prevent ALI after HS by limiting liver cell death.

Citropten Inhibits Vascular Smooth Muscle Cell Proliferation and Migration via the TRPV1 Receptor.

Vascular smooth muscle cell (VSMC) proliferation and migration play critical roles in arterial remodeling. Citropten, a natural organic compound belonging to coumarin and its derivative classes, exhibits various biological activities. However, mechanisms by which citropten protects against vascular remodeling remain unknown. Therefore, in this study, we investigated the inhibitory effects of citropten on VSMC proliferation and migration under high-glucose (HG) stimulation. Citropten abolished the proliferation and migration of rat vascular smooth muscle cells (RVSMCs) in a concentration-dependent manner. Also, citropten inhibited the expression of proliferation-related proteins, including proliferating cell nuclear antigen (PCNA), cyclin E1, cyclin D1, and migration-related markers such as matrix metalloproteinase (MMP), MMP2 and MMP9, in a concentration-dependent manner. In addition, citropten inhibited the phosphorylation of ERK and AKT, as well as hypoxia-inducible factor-1α (HIF-1α) expression, mediated to the Krüppel-like factor 4 (KLF4) transcription factor. Using pharmacological inhibitors of ERK, AKT, and HIF-1α also strongly blocked the expression of MMP9, PCNA, and cyclin D1, as well as migration and the proliferation rate. Finally, molecular docking suggested that citropten docked onto the binding site of transient receptor potential vanilloid 1 (TRPV1), like epigallocatechin gallate (EGCG), a well-known agonist of TRPV1. These data suggest that citropten inhibits VSMC proliferation and migration by activating the TRPV1 channel.

Effect of moxibustion at "Xinshu" (BL15) and "Feishu" (BL13) on expression of TRPV1 and CGRP in the myocardial tissue of chronic heart failure rats.

To observe the effect of moxibustion at "Xinshu" (BL15) and "Feishu" (BL13) on transient receptor potential vanilloid type 1(TRPV1), calcitonin gene-related peptide (CGRP), and serum interleukin-10 (IL-10) in the myocardial tissue of rats with chronic heart failure (CHF), so as to explore its underlying mechanisms in improvement of CHF. Male SD rats were randomly divided into the normal, model, moxibustion, capsaicin, moxibustion + capsaicin, and moxibustion + solvent groups, with 10 rats in each group. The CHF model was established by permanent ligation of the anterior descending branch of the left coronary artery. Mild moxibustion was applied to bilateral BL13 and BL15 for 30 min once daily for 4 weeks. Rats in the capsaicin group were smeared with capsaicin in the acupoint area once a day for 4 weeks. For rats of the moxibustion + capsaicin and moxibustion + solvent groups, capsaicin and solvent were applied to the acupoint area before moxibustion for 4 weeks, respectively. The ejection fraction (EF) and left ventricular fractional shortening rate (FS) were examined by echocardiography. HE staining was used to observe the myecardial morphological structure. The mRNA and protein expression levels of TRPV1, CGRP and galectin-3 (Gal-3) in myocardial tissue were detected by real-time quantitative PCR and Western blot, respectively. The content of IL-10 in serum was detected by ELISA. After modeling, the pathological changes of myocardium (as cardiac muscle fiber disorder, inflammatory cell infiltration, etc.) were obvious, and the EF, FS, serum IL-10, protein and mRNA exspression of TRPV1 and CGRP were significantly decreased (P<0.01) in the model group compared with the normal group, while the protein and mRNA exspression of Gal-3 were significantly up-regulated (P<0.01). Following the interventions, the above-mentioned indexes were all reversed in moxibustion, capsaicin, and moxibustion + capsaicin groups (P<0.01), and the effect of moxibustion + capsaicin was the best (P<0.05, P<0.01). Moxibustion can reduce myocardial injury and improve cardiac function in CHF rats, which may be related to its effects in up-regulating the expression of TRPV1 and CGRP, and down-regulating the expression of Gal-3 to alleviate myocardial fibrosis.

Eugenol mimics exercise to promote skeletal muscle fiber remodeling and myokine IL-15 expression by activating TRPV1 channel

Metabolic disorders are highly prevalent in modern society. Exercise mimetics are defined as pharmacological compounds that can produce the beneficial effects of fitness. Recently, there has been increased interest in the role of eugenol and transient receptor potential vanilloid 1 (TRPV1) in improving metabolic health. The aim of this study was to investigate whether eugenol acts as an exercise mimetic by activating TRPV1. Here, we showed that eugenol improved endurance capacity, caused the conversion of fast-to-slow muscle fibers, and promoted white fat browning and lipolysis in mice. Mechanistically, eugenol promoted muscle fiber-type transformation by activating TRPV1-mediated CaN signaling pathway. Subsequently, we identified IL-15 as a myokine that is regulated by the CaN/nuclear factor of activated T cells cytoplasmic 1 (NFATc1) signaling pathway. Moreover, we found that TRPV1-mediated CaN/NFATc1 signaling, activated by eugenol, controlled IL-15 levels in C2C12 myotubes. Our results suggest that eugenol may act as an exercise mimetic to improve metabolic health via activating the TRPV1-mediated CaN signaling pathway.

Eugenol mimics exercise to promote skeletal muscle fiber remodeling and myokine IL-15 expression by activating TRPV1 channel.

Metabolic disorders are highly prevalent in modern society. Exercise mimetics are defined as pharmacological compounds that can produce the beneficial effects of fitness. Recently, there has been increased interest in the role of eugenol and transient receptor potential vanilloid 1 (TRPV1) in improving metabolic health. The aim of this study was to investigate whether eugenol acts as an exercise mimetic by activating TRPV1. Here, we showed that eugenol improved endurance capacity, caused the conversion of fast-to-slow muscle fibers, and promoted white fat browning and lipolysis in mice. Mechanistically, eugenol promoted muscle fiber-type transformation by activating TRPV1-mediated CaN signaling pathway. Subsequently, we identified IL-15 as a myokine that is regulated by the CaN/nuclear factor of activated T cells cytoplasmic 1 (NFATc1) signaling pathway. Moreover, we found that TRPV1-mediated CaN/NFATc1 signaling, activated by eugenol, controlled IL-15 levels in C2C12 myotubes. Our results suggest that eugenol may act as an exercise mimetic to improve metabolic health via activating the TRPV1-mediated CaN signaling pathway.

Light-Inducible Activation of TrkA for Probing Chronic Pain in Mice.

Chronic pain is a prevalent problem that plagues modern society, and better understanding its mechanisms is critical for developing effective therapeutics. Nerve growth factor (NGF) and its primary receptor, Tropomyosin receptor kinase A (TrkA), are known to be potent mediators of chronic pain, but there is a lack of established methods for precisely perturbing the NGF/TrkA signaling pathway in the study of pain and nociception. Optobiological tools that leverage light-induced protein-protein interactions allow for precise spatial and temporal control of receptor signaling. Previously, our lab reported a blue light-activated version of TrkA generated using light-induced dimerization of the intracellular TrkA domain, opto-iTrkA. In this work, we show that opto-iTrkA activation is able to activate endogenous ERK and Akt signaling pathways and causes the retrograde transduction of phospho-ERK signals in dorsal root ganglion (DRG) neurons. Opto-iTrkA activation also sensitizes the transient receptor potential vanilloid 1 (TRPV1) channel in cellular models, further corroborating the physiological relevance of the optobiological stimulus. Finally, we show that opto-iTrkA enables light-inducible potentiation of mechanical sensitization in mice. Light illumination enables nontraumatic and reversible (<2 days) sensitization of mechanical pain in mice transduced with opto-iTrkA, which provides a platform for dissecting TrkA pathways for nociception in vitro and in vivo.

The GABAergic pathway from anterior cingulate cortex to lateral hypothalamus area regulates irritable bowel syndrome in mice and its underlying mechanism.

Irritable bowel syndrome (IBS), which is characterized by chronic abdominal pain, has a high global prevalence. The anterior cingulate cortex (ACC), which is a pivotal region involved in pain processing, should be further investigated regarding its role in the regulation of visceral sensitivity and mental disorders. A C57BL/6J mouse model for IBS was established using chronic acute combining stress (CACS). IBS-like symptoms were assessed using behavioral tests, intestinal motility measurements, and abdominal withdrawal reflex scores. Fluoro-Gold retrograde tracing and immunohistochemistry techniques were employed to investigate the projection of ACC gamma-aminobutyric acid-producing (GABAergic) neurons to the lateral hypothalamus area (LHA). Chemogenetic approaches enabled the selective activation or inhibition of the ACC-LHA GABAergic pathway. Enzyme-linked immunosorbent assay (ELISA) and western blot analyses were conducted to determine the expression of histamine, 5-hydroxytryptamine (5-HT), and transient receptor potential vanilloid 4 (TRPV4). Our findings suggest that CACS induced IBS-like symptoms in mice. The GABA type A receptors (GABAAR) within LHA played a regulatory role in modulating IBS-like symptoms. The chemogenetic activation of ACC-LHA GABAergic neurons elicited anxiety-like behaviors, intestinal dysfunction, and visceral hypersensitivity in normal mice; however, these effects were effectively reversed by the administration of the GABAAR antagonist Bicuculline. Conversely, the chemogenetic inhibition of ACC-LHA GABAergic neurons alleviated anxiety-like behaviors, intestinal dysfunction, and visceral hypersensitivity in the mouse model for IBS. These results highlight the crucial involvement of the ACC-LHA GABAergic pathway in modulating anxiety-like behaviors, intestinal motility alterations, and visceral hypersensitivity, suggesting a potential therapeutic strategy for alleviating IBS-like symptoms.

Identification and Properties of TRPV4 Mutant Channels Present in Polycystic Kidney Disease Patients.

Polycystic kidney disease (PKD), a disease characterized by the enlargement of the kidney through cystic growth is the fourth leading cause of end-stage kidney disease world-wide. Transient receptor potential Vanilloid 4 (TRPV4), a calcium-permeable TRP, channel participates in kidney cell physiology and since TRPV4 forms complexes with another channel whose malfunction is associated to PKD, TRPP2 (or PKD2), we sought to determine whether patients with PKD, exhibit previously unknown mutations in TRPV4. Here, we report the presence of mutations in the TRPV4 gene in patients diagnosed with PKD and determine that they produce gain-of-function (GOF). Mutations in the sequence of the TRPV4 gene have been associated to a broad spectrum of neuropathies and skeletal dysplasias but not PKD, and their biophysical effects on channel function have not been elucidated. We identified and examined the functional behavior of a novel E6K mutant and of the previously known S94L and A217S mutant TRVP4 channels. The A217S mutation has been associated to mixed neuropathy and/or skeletal dysplasia phenotypes, however, the PKD carriers of these variants had not been diagnosed with these reported clinical manifestations. The presence of certain mutations in TRPV4 may influence the progression and severity of PKD through GOF mechanisms. PKD patients carrying TRVP4 mutations are putatively more likely to require dialysis or renal transplant as compared to those without these mutations.

Toward high-resolution modeling of small molecule-ion channel interactions.

Ion channels are critical drug targets for a range of pathologies, such as epilepsy, pain, itch, autoimmunity, and cardiac arrhythmias. To develop effective and safe therapeutics, it is necessary to design small molecules with high potency and selectivity for specific ion channel subtypes. There has been increasing implementation of structure-guided drug design for the development of small molecules targeting ion channels. We evaluated the performance of two RosettaLigand docking methods, RosettaLigand and GALigandDock, on the structures of known ligand-cation channel complexes. Ligands were docked to voltage-gated sodium (NaV), voltage-gated calcium (CaV), and transient receptor potential vanilloid (TRPV) channel families. For each test case, RosettaLigand and GALigandDock methods frequently sampled a ligand-binding pose within a root mean square deviation (RMSD) of 1-2Å relative to the experimental ligand coordinates. However, RosettaLigand and GALigandDock scoring functions cannot consistently identify experimental ligand coordinates as top-scoring models. Our study reveals that the proper scoring criteria for RosettaLigand and GALigandDock modeling of ligand-ion channel complexes should be assessed on a case-by-case basis using sufficient ligand and receptor interface sampling, knowledge about state-specific interactions of the ion channel, and inherent receptor site flexibility that could influence ligand binding.

Involvement of the TRPV1 receptor and the endocannabinoid system in schizophrenia

BackgroundSchizophrenia (SCZ) is a severe mental disorder, but its pathogenesis is still unknown, and its clinical treatment effect is very limited. Transient receptor potential vanilloid 1 (TRPV1) channel and the Endocannabinoid System (ECS)have been confirmed to be involved in the pathogenesis of SCZ, although their actions have not been fully clarified yet. The objective is to examine TRPV1 and ECS expression in the blood of schizophrenia patients and investigate their correlation with disease severity. MethodsThis is a cross-sectional investigation. Peripheral blood samples were gathered from normal controls (NC, n=37), as well as individuals with schizophrenia, including first episode (n=30) and recurrent (n=30) cases. We employed western blot and ELISA techniques to quantify TRPV1, cannabinoid receptors 1(CB1), anandamide (AEA), and 2-arachidonoylglycerol (2-AG), and assess the severity of the patient's symptoms by means of the PANSS scale. ResultsCompared to NC, TRPV1 levels showed a noticeable decrease in both first episode schizophrenia (f-SCZ group) and recurrent schizophrenia (r-SCZ group) subjects. Additionally, CB1 levels appeared increased in f-SCZ group. Furthermore, 2-AG levels were found to be elevated in both f-SCZ group and r-SCZ group compared to NC, whereas AEA levels were decreased in f-SCZ group but increased in r-SCZ group. Moreover, among schizophrenia patients, TRPV1 demonstrated a negative correlation with negative symptoms. Within r-SCZ subjects, CB1 displayed a negative correlation with relapse number, while 2-AG showed a correlation in the opposite direction. ConclusionsThis study provides initial clinical evidence of changed TRPV1 expression in schizophrenia, potentially linked to negative symptoms. These results suggest a possible dysfunction of TRPV1 and the endocannabinoid system (ECS), which might offer new avenues for medical interventions.

Association between Variants of the TRPV1 Gene and Body Composition in Sub-Saharan Africans.

In humans, the transient receptor potential vanilloid 1 (TRPV1) gene is activated by exogenous (e.g., high temperatures, irritating compounds such as capsaicin) and endogenous (e.g., endocannabinoids, inflammatory factors, fatty acid metabolites, low pH) stimuli. It has been shown to be involved in several processes including nociception, thermosensation, and energy homeostasis. In this study, we investigated the association between TRPV1 gene variants, sensory perception (to capsaicin and PROP), and body composition (BMI and bioimpedance variables) in human populations. By comparing sequences deposited in worldwide databases, we identified two haplotype blocks (herein referred to as H1 and H2) that show strong stabilizing selection signals (MAF approaching 0.50, Tajima's D > +4.5) only in individuals with sub-Saharan African ancestry. We therefore studied the genetic variants of these two regions in 46 volunteers of sub-Saharan descent and 45 Italian volunteers (both sexes). Linear regression analyses showed significant associations between TRPV1 diplotypes and body composition, but not with capsaicin perception. Specifically, in African women carrying the H1-b and H2-b haplotypes, a higher percentage of fat mass and lower extracellular fluid retention was observed, whereas no significant association was found in men. Our results suggest the possible action of sex-driven balancing selection at the non-coding sequences of the TRPV1 gene, with adaptive effects on water balance and lipid deposition.

Transient receptor potential vanilloid 1 involved in the analgesic effects of total flavonoids extracted from Longxuejie ().

To evaluate the analgesic effects of total flavonoids of Longxuejie (Resina Dracaenae Cochinchinensis) (TFDB) and explore the possible analgesic mechanism associated with transient receptor potential vanilloid 1 (TRPV1). Whole-cell patch clamp technique was used to observe the effects of TFDB on capsaicin-induced TRPV1 currents. Rat experiments in vivo were used to observe the analgesic effects of TFDB. Western blot and immunofluorescence experiments were used to test the change of TRPV1 expression in DRG neurons induced by TFDB. Results showed that TFDB inhibited capsaicin-induced TRPV1 receptor currents in acutely isolated dorsal root ganglion (DRG) neurons of rats and the half inhibitory concentration was (16.7 ± 1.6) mg/L. TFDB (2-20 mg/kg) showed analgesic activity in the phase Ⅱ of formalin test and (0.02-2 mg per paw) reduced capsaicin-induced licking times of rats. TFDB (20 mg/kg) was fully efficacious on complete Freund's adjuvant (CFA)-induced inflammatory thermal hyperalgesia and capsaicin could weaken the analgesic effects. The level of TRPV1 expressions of DRG neurons was also decreased in TFDB-treated CFA-inflammatory pain rats. All these results indicated that the analgesic effect of TFDB may contribute to their modulations on both function and expression of TRPV1 channels in DRG neurons.

Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine

ObjectiveTo explore the differential expression and mechanisms of bone formation-related genes in osteoporosis (OP) leveraging bioinformatics and machine learning methodologies, and to predict the active ingredients of targeted traditional Chinese medicine (TCM) herbs. MethodsThe Gene Expression Omnibus (GEO) and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP. The R package was utilized as the analytical tool for the identification of differentially expressed genes. Least absolute shrinkage and selection operator (LASSO) logistic regression analysis and support vector machine-recursive feature elimination (SVM-RFE) algorithm were employed in defining the genetic signature specific to OP. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses for the selected pivotal genes were conducted. The cell-type identification by estimating relative subsets of RNA transcripts (CIBERSORT) algorithm was leveraged to examine the infiltration patterns of immune cells, with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells. Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP. Comparative Toxicogenomics Database (CTD) was employed for forecasting the TCM active ingredients targeting the key genes. AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results, facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets. ResultsTen genes were identified by intersecting the results from the GEO and GeneCards databases. Through the application of LASSO regression and SVM-RFE algorithm, four pivotal genes were selected: coat protein (CP), kallikrein 3 (KLK3), polymerase γ (POLG), and transient receptor potential vanilloid 4 (TRPV4). GO and KEGG pathway enrichment analyses revealed that these trait genes were predominantly engaged in the regulation of defense response activation, maintenance of cellular metal ion balance, and the production of chemokine ligand 5. These genes were notably associated with signaling pathways such as ferroptosis, porphyrin metabolism, and base excision repair. Immune infiltration analysis showed that key genes were highly correlated with immune cells. Macrophage M0, M1, M2, and resting dendritic cell were significantly different between groups, and there were significant differences between different groups (P < 0.05). The interaction counts of resveratrol, curcumin, and quercetin with KLK3 were 7, 3, and 2, respectively. It shows that the interactions of resveratrol, curcumin, and quercetin with KLK3 were substantial. Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes. ConclusionPivotal genes including CP, KLK3, POLG, and TRPV4, exhibited commendable significant prognostic value, and played a crucial role in the diagnostic assessment of OP. Resveratrol, curcumin, and quercetin, natural compounds found in TCM, showed promise in their potential to effectively modulate the bone-forming gene KLK3. This study provides a scientific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs.

Inhibitory Effect of Evodiamine on Psoriasis Lesions and Itching in Mice.

This study seeks to investigate the effect of evodiamine on psoriasis and psoriatic pruritus. Imiquimod-induced psoriasiform dermatitis in mice was used as a model, and evodiamine was topically applied for seven days. The mice were observed daily for skin damage on the back, clinical score and their scratching behavior was recorded. Blood samples were collected on the final day of the experiment, and the serum levels of pruritus-associated inflammatory cytokines tumor necrosis factor (TNF) -α, interleukin (IL) -23, and IL-17A were measured using enzyme-linked immunosorbent assay. Histopathological changes were observed in Hematoxylin and Eosin-stained skin specimens. The expression levels of transient receptor potential vanilloid (TRPV) 1, TRPV3, TRPV4, and the pruritus-related mediators Substance P (SP), nerve growth factor (NGF), and calcitonin gene-related peptide (CGRP) in the skin lesions were analyzed using Western blot and qRT-PCR. The effect of evodiamine on the exploratory behavior, motor, and coordination abilities of mice was assessed using open field, suspension, and Rota-Rod experiments. Molecular docking was utilized to verify the binding of evodiamine to the residues of TRPV1, TRPV3, and TRPV4. Evodiamine reduced pruritus and inhibited inflammation by decreasing the levels of inflammatory mediators TNF-α, IL-23, and IL-17A in the serum of Imiquimod-induced mice and attenuated the mRNA and protein expression levels of SP, NGF, CGRP, TRPV1, TRPV3, and TRPV4 in the skin. Evodiamine is an effective treatment for psoriasis and pruritus, due to its ability to inhibit immune inflammation and pruritic mediators.

Far-infrared irradiation increases the uptake of LDL cholesterol by downregulating PCSK9 through the activation of TRPV4 calcium channels in HepG2 cells

This study investigated the effects of far-infrared (FIR) irradiation on low-density lipoprotein cholesterol (LDL-C) uptake by human hepatocellular carcinoma G2 (HepG2) cells via the regulation of proprotein convertase subtilisin/kexin type 9 (PCSK9). FIR irradiation for 30 min significantly decreased PCSK9 expression (p < 0.01) in HepG2 cells. FIR irradiation substantially increased the low-density lipoprotein receptor (p < 0.0001) and LDL-C uptake (p < 0.01). Activation of transient receptor potential vanilloid (TRPV) channels mimicked the effects of FIR irradiation, significantly decreasing the protein expression of PCSK9 (p < 0.05). Conversely, inhibition of TRP channels using ruthenium red reversed the reduction in PCSK9 protein expression following FIR irradiation (p < 0.01). The specific activation of TRPV4 using 4α-PDD mimicked the effect of FIR irradiation (p < 0.01), whereas PCSK9 reduction by FIR irradiation was significantly reversed by the inhibition of TRPV4 using RN1734 (p < 0.05). These findings implied that FIR irradiation emitted from a ceramic lamp specifically increased TRPV4 activity. These findings provide insights into a novel therapeutic approach using FIR irradiation for LDL-C regulation and its implications for cardiovascular health.

Repeated doses of captopril induce airway hyperresponsiveness by modulating the TRPV1 receptor in rats

Although TRPV1 receptors play an essential role in the adverse effects on the airways following captopril treatment, there is no available evidence of their involvement in treatment regimens involving repeated doses of captopril. Comparing the difference in these two treatment regimens is essential since captopril is a continuous-use medication. Thus, this study explored the role of the transient receptor potential vanilloid 1 (TRPV1) in the effects of captopril on rat airways using two treatment regimens. Airway resistance, bronchoalveolar lavage (BAL), and histological and immunohistochemical analyses were conducted in rats administered with single or repeated doses of captopril. This study showed that the hyperresponsiveness to bradykinin and capsaicin in captopril-treated rats was acute. Treatment with the selective B2 antagonist, HOE140 reduced bradykinin hyperresponsiveness and abolished capsaicin exacerbation in single-dose captopril-treated rats. Likewise, degeneration of TRPV1-positive neurones also reduced hyperresponsiveness to bradykinin. Single-dose captopril treatment increased leukocyte infiltration in the BAL when compared with the vehicle and this increase was reduced by TRPV1-positive neurone degeneration. However, when compared with the vehicle treatment, animals treated with repeated doses of captopril showed an increase in leukocyte influx as early as 1 h after the last captopril treatment, but this effect disappeared after 24 h. Additionally, an increase in TRPV1 expression occurred only in animals who received repeated captopril doses and the degeneration of TRPV1-positive neurones attenuated TRPV1 upregulation. In conclusion, these data strongly indicate that a treatment regimen involving multiple doses of captopril not only enhances sensitisation but also upregulates TRPV1 expression. Consequently, targeting TRPV1 could serve as a promising strategy to reduce the negative impact of captopril on the airways.

TRPV1 nociceptors are required to optimize antigen-specific primary antibody responses to novel antigens

BackgroundKey to the advancement of the field of bioelectronic medicine is the identification of novel pathways of neural regulation of immune function. Sensory neurons (termed nociceptors) recognize harmful stimuli and initiate a protective response by eliciting pain and defensive behavior. Nociceptors also interact with immune cells to regulate host defense and inflammatory responses. However, it is still unclear whether nociceptors participate in regulating primary IgG antibody responses to novel antigens.MethodsTo understand the role of transient receptor potential vanilloid 1 (TRPV1)-expressing neurons in IgG responses, we generated TRPV1-Cre/Rosa-ChannelRhodopsin2 mice for precise optogenetic activation of TRPV1 + neurons and TRPV1-Cre/Lox-diphtheria toxin A mice for targeted ablation of TRPV1-expressing neurons. Antigen-specific antibody responses were longitudinally monitored for 28 days.ResultsHere we show that TRPV1 expressing neurons are required to develop an antigen-specific immune response. We demonstrate that selective optogenetic stimulation of TRPV1+ nociceptors during immunization significantly enhances primary IgG antibody responses to novel antigens. Further, mice rendered deficient in TRPV1- expressing nociceptors fail to develop primary IgG antibody responses to keyhole limpet hemocyanin or haptenated antigen.ConclusionThis functional and genetic evidence indicates a critical role for nociceptor TRPV1 in antigen-specific primary antibody responses to novel antigens. These results also support consideration of potential therapeutic manipulation of nociceptor pathways using bioelectronic devices to enhance immune responses to foreign antigens.