Transient Receptor Potential (TRP) Channels

Photobiomodulation: a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells

JOURNAL/nrgr/04.03/01300535-202502000-00035/figure1/v/2024-05-28T214302Z/r/image-tiff Photobiomodulation, originally used red and near-infrared lasers, can alter cellular metabolism. It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation, near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration, which is necessary for the cells homing to the site of injury. In this in vitro study, we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries. We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2. As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects. Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers, with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group. Interestingly, green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation, while near-infrared photobiomodulation notably increased the expression of neuronal markers. Through biochemical analysis and enzyme-linked immunosorbent assays, we observed marked improvements in viability, proliferation, membrane permeability, and mitochondrial membrane potential, as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor. Overall, our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells, offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries.

Roles of TRPM channels in glioma

Gliomas are the most common type of primary brain tumor. Despite advances in treatment, it remains one of the most aggressive and deadly tumor of the central nervous system (CNS). Gliomas are characterized by high malignancy, heterogeneity, invasiveness, and high resistance to radiotherapy and chemotherapy. It is urgent to find potential new molecular targets for glioma. The TRPM channels consist of TRPM1-TPRM8 and play a role in many cellular functions, including proliferation, migration, invasion, angiogenesis, etc. More and more studies have shown that TRPM channels can be used as new therapeutic targets for glioma. In this review, we first introduce the structure, activation patterns, and physiological functions of TRPM channels. Additionally, the pathological mechanism of glioma mediated by TRPM2, 3, 7, and 8 and the related signaling pathways are described. Finally, we discuss the therapeutic potential of targeting TRPM for glioma.

5-HT/CGRP pathway and Sumatriptan role in Covid-19

Coronavirus disease 2019 (Covid-19) is a pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). In Covid-19, there is uncontrolled activation of immune cells with a massive release of pro-inflammatory cytokines and the development of cytokine storm. These inflammatory changes induce impairment of different organ functions, including the central nervous system (CNS), leading to acute brain injury and substantial changes in the neurotransmitters, including serotonin (5-HT) and calcitonin gene-related peptide (CGRP), which have immunomodulatory properties through modulation of central and peripheral immune responses. In Covid-19, 5-HT neurotransmitters and CGRP could contribute to abnormal and atypical vascular reactivity. Sumatriptan is a pre-synaptic 5-HT (5-HT1D and 5-HT1B) agonist and inhibits the release of CGRP. Both 5-HT and CGRP seem to be augmented in Covid-19 due to underlying activation of inflammatory signaling pathways and hyperinflammation. In virtue of its anti-inflammatory and antioxidant properties with inhibition release of 5-HT and CGRP, Sumatriptan may reduce Covid-19 hyperinflammation. Therefore, Sumatriptan might be a novel potential therapeutic strategy in managing Covid-19. In conclusion, Sumatriptan could be an effective therapeutic strategy in managing Covid-19 through modulation of 5-HT neurotransmitters and inhibiting CGRP.

TRPM2 knockdown attenuates myocardial apoptosis and promotes autophagy in HFD/STZ-induced diabetic mice via regulating the MEK/ERK and mTORC1 signaling pathway

Diabetic cardiomyopathy (DCM) is a major complication of diabetes. Transient receptor potential melastatin 2 (TRPM2) activity increases in diabetic oxidative stress state, and it is involved in myocardial damage and repair. We explore the protective effect of TRPM2 knockdown on the progression of DCM. A type 2 diabetes animal model was established in C57BL/6N mice by long-term high-fat diet (HFD) feeding combined with a single injection of 100-mg/kg streptozotocin (STZ). Genetic knockdown of TRPM2 in heart was accomplished by the intravenous injection via the tail vein of adeno-associated virus type 9 carrying TRPM2 shRNA. Neonatal rat ventricular myocytes was exposed to 45 mM of high-glucose (HG) stimulation for 72 h in vitro to mimic the in vivo conditions. Western blot, real-time quantitative PCR (RT-qPCR), immunohistochemistry and fluorescence, electron, CCK-8, and flow cytometry were used to evaluate the phenotype of cardiac inflammation, fibrosis, apoptosis, and autophagy. Mice with HFD/STZ-induced diabetes exhibited systolic and diastolic dysfunction, as demonstrated by increased myocardial apoptosis and autophagy inhibition in the heart. Compared to control group, the protein expression of TRPM2, bax, cleaved caspase-3, and P62 was significantly elevated, and the protein expression of bcl-2 and LC3-II was significantly decreased in the myocardial tissues of the HFD/STZ-induced diabetes group. Knockdown of TRPM2 significantly reversed the HFD/STZ-induced myocardial apoptosis and autophagy inhibition. TRPM2 silencing attenuated HG-induced apoptosis and autophagy inhibition in primary cardiomyocytes via regulating the MEK/ERK mTORC1 signaling pathway. TRPM2 knockdown attenuates hyperglycemia-induced myocardial apoptosis and promotes autophagy in HFD/STZ-induced diabetic mice or HG-stimulated cardiomyocytes via regulating the MEK/ERK and mTORC1 signaling pathway.

Recent advances on the structure and the function relationships of the TRPV4 ion channel

The members of the superfamily of Transient Receptor Potential (TRP) ion channels are physiologically important molecules that have been studied for many years and are still being intensively researched. Among the vanilloid TRP subfamily, the TRPV4 ion channel is an interesting protein due to its involvement in several essential physiological processes and in the development of various diseases. As in other proteins, changes in its function that lead to the development of pathological states, have been closely associated with modification of its regulation by different molecules, but also by the appearance of mutations which affect the structure and gating of the channel. In the last few years, some structures for the TRPV4 channel have been solved. Due to the importance of this protein in physiology, here we discuss the recent progress in determining the structure of the TRPV4 channel, which has been achieved in three species of animals (Xenopus tropicalis, Mus musculus, and Homo sapiens), highlighting conserved features as well as key differences among them and emphasizing the binding sites for some ligands that play crucial roles in its regulation.

Pathophysiological significance and modulation of the transient receptor potential canonical 3 ion channel

Transient receptor potential canonical 3 (TRPC3) protein belongs to the TRP family of nonselective cation channels. Its activation occurs by signaling through a G protein-coupled receptor (GPCR) and a phospholipase C-dependent (PLC) pathway. Perturbations in the expression of TRPC3 are associated with a plethora of pathophysiological conditions responsible for disorders of the cardiovascular, immune, and central nervous systems. The recently solved cryo-EM structure of TRPC3 provides detailed inputs about the underlying mechanistic aspects of the channel, which in turn enables more efficient ways of designing small-molecule modulators. Pharmacologically targeting TRPC3 in animal models has demonstrated great efficacy in treating diseases including cancers, neurological disorders, and cardiovascular diseases. Despite extensive scientific evidence supporting some strong correlations between the expression and activity of TRPC3 and various pathophysiological conditions, therapeutic strategies based on its pharmacological modulations have not led to clinical trials. The development of small-molecule TRPC3 modulators with high safety, sufficient brain penetration, and acceptable drug-like profiles remains in progress. Determining the pathological mechanisms for TRPC3 involvement in human diseases and understanding the requirements for a drug-like TRPC3 modulator will be valuable in advancing small-molecule therapeutics to future clinical trials. In this review, we provide an overview of the origin and activation mechanism of TRPC3 channels, diseases associated with irregularities in their expression, and new development in small-molecule modulators as potential therapeutic interventions for treating TRPC3 channelopathies.

Activity Monitoring for Analysis of Sleep in Drosophila melanogaster

Sleep is important for survival, and the need for sleep is conserved across species. In the past two decades, the fruit fly Drosophila melanogaster has emerged as a promising system in which to study the genetic, neural, and physiological bases of sleep. Through significant advances in our understanding of the regulation of sleep in flies, the field is poised to address several open questions about sleep, such as how the need for sleep is encoded, how molecular regulators of sleep are situated within brain networks, and what the functions of sleep are. Here, we describe key findings, open questions, and commonly used methods that have been used to inform existing theories and develop new ways of thinking about the function, regulation, and adaptability of sleep behavior.

Role of phosphorylation and vanilloid ligand structure in ligand-dependent differential activations of transient receptor potential vanilloid 1

Vanilloid analogs, which can activate transient receptor potential vanilloid 1 (TRPV1), have been classified into two types based on susceptibility to forskolin (FSK). Treatment of cells expressing TRPV1 with FSK enhances TRPV1 responses to capsaicin-type ligands while diminishing the responses to eugenol-type ligands. In this study, we determined the effect of FSK on the activation of TRPV1 stimulated with vanilloid ligands, through the influx of Ca2+ in HEK293T cells expressing TRPV1. Our findings suggest that the effects of FSK can be attributed to the phosphorylation of TRPV1, as evidenced by using a protein kinase A inhibitor and TRPV1 mutants at potential phosphorylation sites. Furthermore, we examined the structure-activity relationship of 13 vanilloid analogs. Our results indicated that vanilloid compounds could be classified into three types, that is the previously reported two types and a novel type of 10-shogaol, by which TRPV1 activation was insusceptible to the FSK treatment.

Ischemic Stroke: Pathophysiology and Evolving Treatment Approaches

Stroke remains a leading cause of mortality and disability, with ischemic stroke being the most common type. It occurs due to reduced cerebral blood flow, leading to a cascade of events initiated by oxygen and nutrient deprivation, triggering excitotoxicity, oxidative stress, and inflammation and finally culminating in neuronal injury and death. Key molecular players in ischemic stroke include glutamate receptors, acid-sensing ion channels, and purinergic receptors, exacerbating cellular damage through calcium influx, oxidative stress, and mitochondrial dysfunction. Understanding these mechanisms has shaped therapeutic strategies, such as neuroprotective agents and stem cell therapies. Current treatments such as tissue plasminogen activator (tPA) emphasize timely intervention, yet challenges persist in patient-specific variability and accessibility. This review provides an overview of ischemic stroke pathophysiology, emphasizing cellular responses to ischemia and current and future therapeutic approaches including stem cell therapies aimed at mitigating stroke-induced disabilities and improving long-term outcomes.

Modulation of heteromeric glycine receptor function through high concentration clustering

Ion channels are targeted by many drugs for treating neurological, musculoskeletal, renal and other diseases. These drugs bind to and alter the function of individual channels to achieve desired therapeutic effects. However, many ion channels function in high concentration clusters in their native environment. It is unclear if and how clustering modulates ion channel function. Human heteromeric glycine receptors (GlyRs) are the major inhibitory neurotransmitter receptors in the spinal cord and are active targets for developing chronic pain medications. We show that the α2β heteromeric GlyR assembles with the master postsynaptic scaffolding gephyrin (GPHN) into micron-sized clustered at the plasma membrane after heterologous expression. The inhibitory trans- synaptic adhesion protein neuroligin-2 (NL2) further increases both the cluster sizes and GlyR concentration. The apparent glycine affinity increases monotonically as a function of GlyR concentration but not with cluster size. We also show that ligand re-binding to adjacent GlyRs alters kinetics but not chemical equilibrium. A positively charged N- terminus sequence of the GlyR β subunit was further identified essential for glycine affinity modulation through clustering. Taken together, we propose a mechanism where clustering enhances local electrostatic potential, which in turn concentrates ions and ligands, modulating the function of GlyR. This mechanism is likely universal across ion channel clusters found ubiquitously in biology and provides new perspectives in possible pharmaceutical development.

Identification of the TRPA1 cannabinoid-binding site

Chronic pain accounts for nearly two-thirds of conditions eligible for medical cannabis licenses, yet the mechanisms underlying cannabis-induced analgesia remain poorly understood. The principal phytocannabinoids, the psychoactive Δ9-tetrahydrocannabinol (THC) and non-psychoactive cannabidiol (CBD), exhibit comparable efficacy in pain management. Notably, THC functions as an agonist of cannabinoid receptor 1 (CB1), whereas CBD shows minimal activity on CB1 and CB2 receptors. Elucidating the molecular targets through which phytocannabinoids modulate the pain system is required for advancing our understanding of the pain pathway and optimizing medical cannabis therapies. Transient receptor potential ankyrin 1 (TRPA1), a pivotal chemosensor in the pain pathway, has been identified as a phytocannabinoid target. Unlike most TRPA1 activators, phytocannabinoid activation is not mediated through the electrophilic binding site, suggesting an alternative mechanism. Here, we identified the human TRPA1 channel cannabinoid-binding site (CBS) and demonstrated that mutations at residue Y840 abolished responses to both THC and CBD at saturating concentrations, indicating a shared primary binding site. Molecular modeling revealed distinct interactions of THC and CBD with the Y840 residue within the CBS. Additionally, CBD binds to the adjacent general anesthetic binding site at oversaturating concentrations. Our findings define the CBS of TRPA1 as overlapping with and adjacent to binding sites for other allosteric activators, suggesting that TRPA1 possesses a highly adaptable domain for binding non-electrophilic activators. This underscores its unique role as a chemosensor in the pain pathway. Furthermore, our results provide new insights into the molecular mechanisms of cannabinoid-induced analgesia and identify novel targets for pain management therapies.

Therapeutic ultrasound: an innovative approach for targeting neurological disorders affecting the basal ganglia

The basal ganglia are involved in motor control and action selection, and their impairment manifests in movement disorders such as Parkinson's disease (PD) and dystonia, among others. The complex neuronal circuitry of the basal ganglia is located deep inside the brain and presents significant treatment challenges. Conventional treatment strategies, such as invasive surgeries and medications, may have limited effectiveness and may result in considerable side effects. Non-invasive ultrasound (US) treatment approaches are becoming increasingly recognized for their therapeutic potential for reversibly permeabilizing the blood-brain barrier (BBB), targeting therapeutic delivery deep into the brain, and neuromodulation. Studies conducted on animals and early clinical trials using ultrasound as a therapeutic modality have demonstrated promising outcomes for controlling symptom severity while preserving neural tissue. These results could improve the quality of life for patients living with basal ganglia impairments. This review article explores the therapeutic frontiers of ultrasound technology, describing the brain mechanisms that are triggered and engaged by ultrasound. We demonstrate that this cutting-edge method could transform the way neurological disorders associated with the basal ganglia are managed, opening the door to less invasive and more effective treatments.

A hydrophobic funnel governs monovalent cation selectivity in the ion channel TRPM5

A key capability of ion channels is the facilitation of selective permeation of certain ionic species across cellular membranes at high rates. Due to their physiological significance, ion channels are of great pharmaceutical interest as drug targets. The polymodal signal-detecting transient receptor potential (TRP) superfamily of ion channels forms a particularly promising group of drug targets. While most members of this family permeate a broad range of cations including Ca2+, TRPM4 and TRPM5 are unique due to their strong monovalent selectivity and impermeability for divalent cations. Here, we investigated the mechanistic basis for their unique monovalent selectivity by in silico electrophysiology simulations of TRPM5. Our simulations reveal an unusual mechanism of cation selectivity, which is underpinned by the function of the central channel cavity alongside the selectivity filter. Our results suggest that a subtle hydrophobic barrier at the cavity entrance ("hydrophobic funnel") enables monovalent but not divalent cations to pass and occupy the cavity at physiologically relevant membrane voltages. Monovalent cations then permeate efficiently by a cooperative, distant knock-on mechanism between two binding regions in the extracellular pore vestibule and the central cavity. By contrast, divalent cations do not enter or interact favorably with the channel cavity due to its raised hydrophobicity. Hydrophilic mutations in the transition zone between the selectivity filter and the central channel cavity abolish the barrier for divalent cations, enabling both monovalent and divalent cations to traverse TRPM5.

A comprehensive review of advanced focused ultrasound (FUS) microbubbles-mediated treatment of Alzheimer's disease

Alzheimer's disease (AD) is characterized by progressive neurodegeneration, memory loss, and cognitive impairment leading to dementia and death. The blood-brain barrier (BBB) prevents the delivery of drugs into the brain, which can limit their therapeutic potential in the treatment of AD. Therefore, there is a need to develop new approaches to bypass the BBB for appropriate treatment of AD. Recently, focused ultrasound (FUS) has been shown to disrupt the BBB, allowing therapeutic agents to penetrate the brain. In addition, microbubbles (MBs) as lipophilic carriers can penetrate across the BBB and deliver the active drug into the brain tissue. Therefore, combined with FUS, the drug-encapsulated MBs can pass through the ultrasound-disrupted zone of the BBB and diffuse into the brain tissue. This review provides clear and concise statements on the recent advances of the various FUS-mediated MBs-based carriers developed for delivering AD-related drugs. In addition, the sonogenetics-based FUS/MBs approaches for the treatment of AD are highlighted. The future perspectives and challenges of ultrasound-based MBs drug delivery in AD are then discussed.

Functions of TRPs in retinal tissue in physiological and pathological conditions

The Transient Receptor Potential (TRP) constitutes a family of channels subdivided into seven subfamilies: Ankyrin (TRPA), Canonical (TRPC), Melastatin (TRPM), Mucolipin (TRPML), no-mechano-potential C (TRPN), Polycystic (TRPP), and Vanilloid (TRPV). Although they are structurally similar to one another, the peculiarities of each subfamily are key to the response to stimuli and the signaling pathway that each one triggers. TRPs are non-selective cation channels, most of which are permeable to Ca2+, which is a well-established second messenger that modulates several intracellular signaling pathways and is involved in physiological and pathological conditions in various cell types. TRPs depolarize excitable cells by increasing the influx of Ca2+, Na+, and other cations. Most TRP families are activated by temperature variations, membrane stretching, or chemical agents and, therefore, are defined as polymodal channels. All TPRs are expressed, at some level, in the central nervous system (CNS) and ocular-related structures, such as the retina and optic nerve (ON), except the TRPP in the ON. TRPC, TRPM, TRPV, and TRPML are found in the retinal pigmented cells, whereas only TRPA1 and TRPM are detected in the uvea. Accordingly, several studies have focused on the search to unravel the role of TRPs in physiological and pathological conditions related to the eyes. Thus, this review aims to shed light on endogenous and exogenous modulators, triggered cell signaling pathways, and localization and roles of each subfamily of TRP channels in physiological and pathological conditions in the retina, optic nerve, and retinal pigmented epithelium of vertebrates.

TLR4 induced TRPM2 mediated neuropathic pain

Ion channels play an important role in mediating pain through signal transduction, regulation, and control of responses, particularly in neuropathic pain. Transient receptor potential channel superfamily plays an important role in cation permeability and cellular signaling. Transient receptor potential channel Melastatin 2 (TRPM2) subfamily regulates Ca2+ concentration in response to various chemicals and signals from the surrounding environment. TRPM2 has a role in several physiological functions such as cellular osmosis, temperature sensing, cellular proliferation, as well as the manifestation of many disease processes such as pain process, cancer, apoptosis, endothelial dysfunction, angiogenesis, renal and lung fibrosis, and cerebral ischemic stroke. Toll-like Receptor 4 (TLR4) is a critical initiator of the immune response to inflammatory stimuli, particularly those triggered by Lipopolysaccharide (LPS). It activates downstream pathways leading to the production of oxidative molecules and inflammatory cytokines, which are modulated by basal and store-operated calcium ion signaling. The cytokine production and release cause an imbalance of antioxidant enzymes and redox potential in the Endoplasmic Reticulum and mitochondria due to oxidative stress, which results from TLR-4 activation and consequently induces the production of inflammatory cytokines in neuronal cells, exacerbating the pain process. Very few studies have reported the role of TRPM2 and its association with Toll-like receptors in the context of neuropathic pain. However, the molecular mechanism underlying the interaction between TRPM2 and TLR-4 and the quantum of impact in acute and chronic neuropathic pain remains unclear. Understanding the link between TLR-4 and TRPM2 will provide more insights into pain regulation mechanisms for the development of new therapeutic molecules to address neuropathic pain.

Dietary monoterpenoids and human health: Unlocking the potential for therapeutic use

Natural products are widely used in different aspects of our lives - from household cleaners and food production, via cosmetics and aromatherapy, to both alternative and traditional medicine. In our research group, we have recently described several monoterpenoids with potential in the antiviral and anticancer therapy by allosteric targeting of aryl hydrocarbon receptor (AhR). Prior to any practical application, biological effects on human organism must be taken in concern. This review article is focused on the biological effects of 5 monoterpenoids on the human health previously identified as AhR antagonists with a therapeutic potential as antiviral and anticancer agents. We have thoroughly described cytotoxic, anti-inflammatory, anti-proliferative, and anticancer effects, as well as known interactions with nuclear receptors. As clearly demonstrated, monoterpenoids in general represent almost an inexhaustible reservoir of natural compounds possessing the ability to influence, modulate and improve human health.

The dual role of TRPV1 in peripheral neuropathic pain: pain switches caused by its sensitization or desensitization

The transient receptor potential vanilloid 1 (TRPV1) channel plays a dual role in peripheral neuropathic pain (NeuP) by acting as a "pain switch" through its sensitization and desensitization. Hyperalgesia, commonly resulting from tissue injury or inflammation, involves the sensitization of TRPV1 channels, which modulates sensory transmission from primary afferent nociceptors to spinal dorsal horn neurons. In chemotherapy-induced peripheral neuropathy (CIPN), TRPV1 is implicated in neuropathic pain mechanisms due to its interaction with ion channels, neurotransmitter signaling, and oxidative stress. Sensitization of TRPV1 in dorsal root ganglion neurons contributes to CIPN development, and inhibition of TRPV1 channels can reduce chemotherapy-induced mechanical hypersensitivity. In diabetic peripheral neuropathy (DPN), TRPV1 is involved in pain modulation through pathways including reactive oxygen species and cytokine production. TRPV1's interaction with TRPA1 channels further influences chronic pain onset and progression. Therapeutically, capsaicin, a TRPV1 agonist, can induce analgesia through receptor desensitization, while TRPV1 antagonists and siRNA targeting TRPV1 show promise in preclinical studies. Cannabinoid modulation of TRPV1 provides another potential pathway for alleviating neuropathic pain. This review summarizes recent preclinical research on TRPV1 in association with peripheral NeuP.

Label-free optical detection of calcium ion influx in cell-derived nanovesicles using a conical Au/PDMS biosensor

Ion channels, which are key to physiological regulation and drug discovery, control ion flux across membranes, and their dysregulation leads to various diseases. Ca2+ monitoring is crucial for cellular signaling when performing Ca-based assays in ion channel research; these assays are widely utilized in both academic and pharmaceutical contexts for drug screening and pharmacological profiling. However, existing detection methods are limited by slow detection speeds, low throughput, complex processes, and low analyte viability. In this study, we developed a label-free optical biosensing method using a conical Au/polydimethylsiloxane platform tailored to detect Ca2+ influx in A549-originated nanovesicles facilitated by the transient receptor potential ankyrin 1 (TRPA1) channel. Nanovesicles expressing cellular signaling components mimic TRPA1 signal transduction in cell membranes and improve analyte viability. The conical Au/polydimethylsiloxane sensor converted Ca2+ influx events induced by specific agonist exposure into noticeable changes in relative transmittance under visible light. The optical transmittance change accompanying Ca2+ influx resulted in an enhanced sensing response, high accuracy and reliability, and rapid detection (∼5 s) without immobilization or ligand treatments. In the underlying sensing mechanism, morphological variations in nanovesicles, which depend on Ca2+ influx, induce a considerable light scattering change at an interface between the nanovesicle and Au, revealed by optical simulation. This study provides a foundation for developing biosensors based on light-matter interactions. These sensors are simple and cost-effective with superior performance and diverse functionality.

The principles and promising future of sonogenetics for precision medicine

Sonogenetics is an emerging medical technology that uses acoustic waves to control cells through sonosensitive mediators (SSMs) that are genetically encoded, thus remotely and non-invasively modulating specific molecular events and/or biomolecular functions. Sonogenetics has opened new opportunities for targeted spatiotemporal manipulation in the field of gene and cell-based therapies due to its inherent advantages, such as its noninvasive nature, high level of safety, and deep tissue penetration. Sonogenetics holds impressive potential in a wide range of applications, from tumor immunotherapy and mitigation of Parkinsonian symptoms to the modulation of neural reward pathway, and restoration of vision. This review provides a detailed overview of the mechanisms and classifications of established sonogenetics systems and summarizes their applications in disease treatment and management. The review concludes by highlighting the challenges that hinder the further progress of sonogenetics, paving the way for future advances.

Virtual screening, molecular dynamics and density functional theory on pain inhibitors against TRPV1 associating inflammatory conditions

Transient receptor potential vanilloid 1 protein (TRPV1) is expressed widely in skin and sensory neurons that contribute to pain/heat sensation in the human system. TRPV1 gene polymorphisms are susceptible to multiple diseases and it is considered a therapeutic target for various inflammatory conditions. Among the TRPV1 variants, rs8065080 (1911 A > G) plays a vital role in painful osteoarthritis and migraine. The presence of rs8065080 polymorphism may render drug efficacy. This study aimed to identify better antagonists against wild-type and variant TRPV1 that may help in the relief of pain/inflammation. We constructed suitable TRPV1 protein structures for wild-type and rs8065080 variant through a homology modelling approach. A total of 3363 anti-inflammatory compounds with high chemical diversity and good drug-like properties were collected and screened against the generated structures. Molecular docking showed that nobilamide B had the highest binding affinity (-5.83 kcal/mol) towards the wild-type. Whereas, isoquinoline analogue displayed highest binding potency with the variant TRPV1 (-11.65 kcal/mol). Besides those, C18H15F3N4O showed affinity towards both wild-type (-5.53 kcal/mol) and variant TRPV1 (-9.75 kcal/mol). Then, molecular dynamic simulation revealed stable conformation in wild-type and variant TRPV1 upon binding of nobilmaide B, isoquinoline analogue and C18H15F3N4O. Additionally, density functional theory (DFT) using B3LYP hybrid function showed high chemical reactiveness of nobilamie B, isoquinoline analogue and C18H15F3N4O. Overall, our systematic investigations provide, C18H15F3N4O could be a potential analgesic inhibiting both wild-type and variant TRPV1 against inflammatory conditions.

Divergent effects of olfactory receptors on transient receptor potential vanilloid 1 activation by capsaicin and eugenol

We analyzed the effects of olfactory receptors (ORs) on transient receptor potential vanilloid 1 (TRPV1) activation using HEK293T cells co-expressing TRPV1 and OR51E1. We demonstrate here that the effect of OR51E1 on TRPV1 activation varies depending on the two TRPV1 ligands: capsaicin and eugenol. Notably, both of these ligands are vanilloid analogs. OR51E1 enhanced the response of TRPV1 to capsaicin but diminished that to eugenol. OR51E2 also showed similar effects. Based on the susceptibility to the OR's modulatory effects, various TRPV1 ligands could be classified into capsaicin and eugenol types. Activation of OR51E1 enhanced cAMP production. In addition, forskolin exhibited almost identical effects as ORs on TRPV1 responses to both types of ligands. These results suggest that OR51E1-induced cAMP elevation leads to a modification of TRPV1, presumably phosphorylation of TRPV1, which amplifies the susceptibility of TRPV1 to the two types of ligands differently.

The TRPA1 Ion Channel Mediates Oxidative Stress-Related Migraine Pathogenesis

Although the introduction of drugs targeting calcitonin gene-related peptide (CGRP) revolutionized migraine treatment, still a substantial proportion of migraine patients do not respond satisfactorily to such a treatment, and new therapeutic targets are needed. Therefore, molecular studies on migraine pathogenesis are justified. Oxidative stress is implicated in migraine pathogenesis, as many migraine triggers are related to the production of reactive oxygen and nitrogen species (RONS). Migraine has been proposed as a superior mechanism of the brain to face oxidative stress resulting from energetic imbalance. However, the precise mechanism behind the link between migraine and oxidative stress is not known. Nociceptive primary afferent nerve fiber endings express ion channel receptors that change harmful stimuli into electric pain signals. Transient receptor potential cation channel subfamily A member 1 (TRPA1) is an ion channel that can be activated by oxidative stress products and stimulate the release of CGRP from nerve endings. It is a transmembrane protein with ankyrin repeats and conserved cysteines in its N-terminus embedded in the cytosol. TRPA1 may be a central element of the signaling pathway from oxidative stress and NO production to CGRP release, which may play a critical role in headache induction. In this narrative review, we present information on the role of oxidative stress in migraine pathogenesis and provide arguments that TRPA1 may be "a missing link" between oxidative stress and migraine and therefore a druggable target in this disease.

Aqp4a and Trpv4 mediate regulatory cell volume increase for swimming maintenance of marine fish spermatozoa

Volume regulation is essential for cell homeostasis and physiological function. Amongst the sensory molecules that have been associated with volume regulation is the transient receptor potential vanilloid 4 (TRPV4), which is a non-selective cation channel that in conjunction with aquaporins, typically controls regulatory volume decrease (RVD). Here we show that the interaction between orthologous AQP4 (Aqp4a) and TRPV4 (Trpv4) is important for regulatory volume increase (RVI) in post-activated marine fish spermatozoa under high osmotic stress. Based upon electrophysiological, volumetric, and in vivo and ex vivo functional experiments using the pharmacological and immunological inhibition of Aqp4a and Trpv4 our model suggests that upon ejaculation and exposure to the hypertonic seawater, spermatozoon shrinkage is initially mediated by water efflux through Aqp1aa in the flagellar tail. The shrinkage results in an increase in intracellular Ca2+ concentration, and the activation of sperm motility and a Na+/K+/2Cl- (NKCC1) cotransporter. The activity of NKCC1 is required for the initiation of cell swelling, which secondarily activates the Aqp4a-Trpv4 complex to facilitate the influx of water via Aqp4a-M43 and Ca2+ via Trpv4 and L-type channels for the mediation of RVI. The inhibitory experiments show that blocking of each of these events prevents either shrinkage or RVI. Our data thus reveal that post-activated marine fish spermatozoa are capable of initiating RVI under a high hypertonic stress, which is essential for the maintenance of sperm motility.

Qixian granule inhibits ferroptosis in vascular endothelial cells by modulating TRPML1 in the lysosome to prevent postmenopausal atherosclerosis

ETHNOPHARMACOLOGICAL RELEVANCE

QiXian Granule (QXG) is an integrated traditional Chinese medicine formula used to treat postmenopausal atherosclerotic (AS) cardiovascular diseases. The previous studies have found that QXG inhibited isoproterenol (ISO)-induced myocardial remodeling. And its active ingredient, Icraiin, can inhibit ferroptosis by promoting oxidized low-density lipoprotein (xo-LDL)-induced vascular endothelial cell injury and autophagy in atherosclerotic mice. Another active ingredient, Salvianolic Acid B, can suppress ferroptosis and apoptosis during myocardial ischemia/reperfusion injury by reducing ubiquitin-proteasome degradation of Glutathione Peroxidase 4 (GPX4) and down-regulating the reactive oxygen species (ROS)- c-Jun N-terminal kinases (JNK)/mitogen-activated protein kinase (MAPK) pathway.

AIM OF THE STUDY

The objective of this research was to assess the possible impact of QXG on atherosclerosis in postmenopausal individuals and investigate its underlying mechanisms.

MATERIALS AND METHODS

Female ApoE-/- mice underwent ovariectomy and were subjected to a high-fat diet (HFD) to establish a postmenopausal atherosclerosis model. The therapeutic effects of QXG were observed in vivo and in vitro through intraperitoneal injection of erastin, G-protein Coupled Estrogen Receptor (GPER) inhibitor (G15), and silent Mucolipin Transient Receptor Potential Channel 1 (TRPML1) adenovirus injection via tail vein. UPLC-MS and molecular docking techniques identified and evaluated major QXG components, contributing to the investigation of QXG's anti-postmenopausal atherosclerotic effects.

RESULTS

QXG increased serum Estradiol levels, decreased follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels, which indicated QXG had estrogen-like effects in Ovx/ApoE-/- mice. Furthermore, QXG demonstrated the potential to impede the progression of AS in Ovx/ApoE-/- mice, as evidenced by reductions in serum triglycerides (TG), total cholesterol (TC), and low-density lipoprotein-cholesterol (LDL-C) levels. Additionally, QXG inhibited ferroptosis in Ovx/ApoE-/- mice. Notably, UPLC-MS analysis identified a total of 106 active components in QXG. The results of molecular docking analysis demonstrated that Epmedin B, Astragaloside II, and Orientin exhibit strong binding affinity towards TRPML1. QXG alleviates the progression of atherosclerosis by activating TRPML1 through the GPER pathway or directly activating TRPML1, thereby inhibiting GPX4 and ferritin heavy chain (FTH1)-mediated iron pendant disease. In vitro, QXG-treated serum suppressed proliferation, migration, and ox-LDL-induced MMP and ROS elevation in HAECs.

CONCLUSION

QXG inhibited GPX4 and FTH1-mediated ferroptosis in vascular endothelial cells through up-regulating GPER/TRPML1 signaling, providing a potential therapeutic option for postmenopausal females seeking a safe and effective medication to prevent atherosclerosis. The study highlights QXG's estrogenic properties and its promising role in combating postmenopausal atherosclerosis.

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

OBJECTIVE

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).

METHODS

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

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.

CONCLUSION

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.

Dual Role of TRPV1 Channels in Cerebral Stroke: An Exploration from a Mechanistic and Therapeutic Perspective

Transient receptor potential vanilloid subfamily member 1 (TRPV1) has been strongly implicated in the pathophysiology of cerebral stroke. However, the exact role and mechanism remain elusive. TPRV1 channels are exclusively present in the neurovascular system and involve many neuronal processes. Numerous experimental investigations have demonstrated that TRPV1 channel blockers or the lack of TRPV1 channels may prevent harmful inflammatory responses during ischemia-reperfusion injury, hence conferring neuroprotection. However, TRPV1 agonists such as capsaicin and some other non-specific TRPV1 activators may induce transient/slight degree of TRPV1 channel activation to confer neuroprotection through a variety of mechanisms, including hypothermia induction, improving vascular functions, inducing autophagy, preventing neuronal death, improving memory deficits, and inhibiting inflammation. Another factor in capsaicin-mediated neuroprotection could be the desensitization of TRPV1 channels. Based on the summarized evidence, it may be plausible to suggest that TPRV1 channels have a dual role in ischemia-reperfusion-induced cerebral injury, and thus, both agonists and antagonists may produce neuroprotection depending upon the dose and duration. The current review summarizes the dual function of TRPV1 in ischemia-reperfusion-induced cerebral injury models, explains its mechanism, and predicts the future.

Widespread transcriptomic alterations of transient receptor potential channel genes in cancer

Ion channels, in particular transient-receptor potential (TRP) channels, are essential genes that play important roles in many physiological processes. Emerging evidence has demonstrated that TRP genes are involved in a number of diseases, including various cancer types. However, we still lack knowledge about the expression alterations landscape of TRP genes across cancer types. In this review, we comprehensively reviewed and summarised the transcriptomes from more than 10 000 samples in 33 cancer types. We found that TRP genes were widespreadly transcriptomic dysregulated in cancer, which was associated with clinical survival of cancer patients. Perturbations of TRP genes were associated with a number of cancer pathways across cancer types. Moreover, we reviewed the functions of TRP family gene alterations in a number of diseases reported in recent studies. Taken together, our study comprehensively reviewed TRP genes with extensive transcriptomic alterations and their functions will directly contribute to cancer therapy and precision medicine.

Effects of mechanical ventilation on the interstitial extracellular matrix in healthy lungs and lungs affected by acute respiratory distress syndrome: a narrative review

BACKGROUND

Mechanical ventilation, a lifesaving intervention in critical care, can lead to damage in the extracellular matrix (ECM), triggering inflammation and ventilator-induced lung injury (VILI), particularly in conditions such as acute respiratory distress syndrome (ARDS). This review discusses the detailed structure of the ECM in healthy and ARDS-affected lungs under mechanical ventilation, aiming to bridge the gap between experimental insights and clinical practice by offering a thorough understanding of lung ECM organization and the dynamics of its alteration during mechanical ventilation.

MAIN TEXT

Focusing on the clinical implications, we explore the potential of precise interventions targeting the ECM and cellular signaling pathways to mitigate lung damage, reduce inflammation, and ultimately improve outcomes for critically ill patients. By analyzing a range of experimental studies and clinical papers, particular attention is paid to the roles of matrix metalloproteinases (MMPs), integrins, and other molecules in ECM damage and VILI. This synthesis not only sheds light on the structural changes induced by mechanical stress but also underscores the importance of cellular responses such as inflammation, fibrosis, and excessive activation of MMPs.

CONCLUSIONS

This review emphasizes the significance of mechanical cues transduced by integrins and their impact on cellular behavior during ventilation, offering insights into the complex interactions between mechanical ventilation, ECM damage, and cellular signaling. By understanding these mechanisms, healthcare professionals in critical care can anticipate the consequences of mechanical ventilation and use targeted strategies to prevent or minimize ECM damage, ultimately leading to better patient management and outcomes in critical care settings.

Piezo1 channels restrain ILC2s and regulate the development of airway hyperreactivity

Mechanosensitive ion channels sense force and pressure in immune cells to drive the inflammatory response in highly mechanical organs. Here, we report that Piezo1 channels repress group 2 innate lymphoid cell (ILC2)-driven type 2 inflammation in the lungs. Piezo1 is induced on lung ILC2s upon activation, as genetic ablation of Piezo1 in ILC2s increases their function and exacerbates the development of airway hyperreactivity (AHR). Conversely, Piezo1 agonist Yoda1 reduces ILC2-driven lung inflammation. Mechanistically, Yoda1 inhibits ILC2 cytokine secretion and proliferation in a KLF2-dependent manner, as we found that Piezo1 engagement reduces ILC2 oxidative metabolism. Consequently, in vivo Yoda1 treatment reduces the development of AHR in experimental models of ILC2-driven allergic asthma. Human-circulating ILC2s express and induce Piezo1 upon activation, as Yoda1 treatment of humanized mice reduces human ILC2-driven AHR. Our studies define Piezo1 as a critical regulator of ILC2s, and we propose the potential of Piezo1 activation as a novel therapeutic approach for the treatment of ILC2-driven allergic asthma.

The Pentameric Ligand-Gated Ion Channel Family: A New Member of the Voltage Gated Ion Channel Superfamily?

In this report we present seven lines of bioinformatic evidence supporting the conclusion that the Pentameric Ligand-gated Ion Channel (pLIC) Family is a member of the Voltage-gated Ion Channel (VIC) Superfamily. In our approach, we used the Transporter Classification Database (TCDB) as a reference and applied a series of bioinformatic methods to search for similarities between the pLIC family and members of the VIC superfamily. These include: (1) sequence similarity, (2) compatibility of topology and hydropathy profiles, (3) shared domains, (4) conserved motifs, (5) similarity of Hidden Markov Model profiles between families, (6) common 3D structural folds, and (7) clustering analysis of all families. Furthermore, sequence and structural comparisons as well as the identification of a 3-TMS repeat unit in the VIC superfamily suggests that the sixth transmembrane segment evolved into a re-entrant loop. This evidence suggests that the voltage-sensor domain and the channel domain have a common origin. The classification of the pLIC family within the VIC superfamily sheds light onto the topological origins of this family and its evolution, which will facilitate experimental verification and further research into this superfamily by the scientific community.

Upregulation, Functional Association, and Correlated Expressions of TRPV1 and TRPA1 During Telmisartan-Driven Immunosuppression of T Cells

TRPV1 and TRPA1, are known to be functionally expressed in T cells, where these two channels differentially regulate effector immune responses. Telmisartan (TM), an anti-hypertension drug, has been recently repurposed to suppress various inflammatory responses. However, the possible involvement of TRP channels during TM-driven suppression of T cells responses has not been explored yet. In this study, we investigated the potential role of TRPV1 and TRPA1 during TM-driven immunosuppression of T cells in vitro. We observed a significant elevation of both TRPV1 and TRPA1 during TM-induced immunosuppression of T cells.We found that TRPA1 activation-driven suppression of T cell activation and effector cytokine responses during TM treatment is partially, yet significantly overridden by TRPV1 activation. Moreover, the expressions of TRPV1 and TRPA1 were highly correlated in various conditions of T cell. Mechanistically, it might be suggested that TRPV1 and TRPA1 are differentially involved in regulating T cell activation despite the co-elevation of both these TRP channels' expressions in the presence of TM. T cell activation was delineated by CD69 and CD25 expressions along with the effector cytokine levels (IFN-γ and TNF) in TM-driven suppression of T cell. These findings could have broad implications for designing possible future immunotherapeutic strategies, especially in the repurposing of TM for T cell-TRP-directed immune disorders.

Esketamine alleviates hypoxia/reoxygenation injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration

OBJECTIVE

This study aimed to investigate the effect of Esketamine (ESK) on the Hypoxia/Reoxygenation (H/R) injury of cardiomyocytes by regulating TRPV1 and inhibiting the concentration of intracellular Ca2+.

METHODS

The H/R injury model of H9c2 cardiomyocytes was established after 4h hypoxia and 6h reoxygenation. H9c2 cells were treated with different concentrations of ESK or TRPV1 agonist capsaicin (10 μM) or TRPV1 inhibitor capsazepine (1 μM). Cell viability was detected by CCK-8 method, and apoptosis by flow cytometry. Intracellular Ca2+ concentration was evaluated by Fluo-4 AM. LDH, MDA, SOD, and GSH-Px were detected with corresponding commercial kits. TRPV1 and p-TRPV1 proteins were detected by Western blot.

RESULTS

After H/R, H9c2 cell viability decreased, apoptosis increased, intracellular Ca2+ concentration increased, LDH and MDA levels increased, SOD and GSH-Px levels decreased, and p-TRPV1 expression increased. ESK treatment rescued these changes induced by H/R. After up-regulating TRPV1, the protective effect of ESK on H/R injury of H9c2 cells was weakened, while down-regulating TRPV1 could further protect against H/R injury.

CONCLUSION

ESK alleviates H/R injury of cardiomyocytes by regulating TRPV1 expression and inhibiting intracellular Ca2+ concentration.

Channels of Evolution: Unveiling Evolutionary Patterns in Diatom Ca2+ Signalling

Diatoms are important primary producers in marine and freshwater environments, but little is known about the signalling mechanisms they use to detect changes in their environment. All eukaryotic organisms use Ca2+ signalling to perceive and respond to environmental stimuli, employing a range of Ca2+-permeable ion channels to facilitate the movement of Ca2+ across cellular membranes. We investigated the distribution of different families of Ca2+ channels in diatom genomes, with comparison to other members of the stramenopile lineage. The four-domain voltage-gated Ca2+ channels (Cav) are present in some centric diatoms but almost completely absent in pennate diatoms, whereas single-domain voltage-gated EukCatA channels were found in all diatoms. Glutamate receptors (GLRs) and pentameric ligand-gated ion channels (pLGICs) also appear to have been lost in several pennate species. Transient receptor potential (TRP) channels are present in all diatoms, but have not undergone the significant expansion seen in brown algae. All diatom species analysed lacked the mitochondrial uniporter (MCU), a highly conserved channel type found in many eukaryotes, including several stramenopile lineages. These results highlight the unique Ca2+-signalling toolkit of diatoms and indicate that evolutionary gains or losses of different Ca2+ channels may contribute to differences in cellular-signalling mechanisms between species.

Calcium Signaling in Airway Epithelial Cells: Current Understanding and Implications for Inflammatory Airway Disease

Airway epithelial cells play an indispensable role in protecting the lung from inhaled pathogens and allergens by releasing an array of mediators that orchestrate inflammatory and immune responses when confronted with harmful environmental triggers. While this process is undoubtedly important for containing the effects of various harmful insults, dysregulation of the inflammatory response can cause lung diseases including asthma, chronic obstructive pulmonary disease, and pulmonary fibrosis. A key cellular mechanism that underlies the inflammatory responses in the airway is calcium signaling, which stimulates the production and release of chemokines, cytokines, and prostaglandins from the airway epithelium. In this review, we discuss the role of major Ca2+ signaling pathways found in airway epithelial cells and their contributions to airway inflammation, mucociliary clearance, and surfactant production. We highlight the importance of store-operated Ca2+ entry as a major signaling hub in these processes and discuss therapeutic implications of targeting Ca2+ signaling for airway inflammation.

Maternal Cannabis Use during Lactation and Potential Effects on Human Milk Composition and Production: A Narrative Review

Cannabis use has increased sharply in the last 20 y among adults, including reproductive-aged women. Its recent widespread legalization is associated with a decrease in risk perception of cannabis use during breastfeeding. However, the effect of cannabis use (if any) on milk production and milk composition is not known. This narrative review summarizes current knowledge related to maternal cannabis use during breastfeeding and provides an overview of possible pathways whereby cannabis might affect milk composition and production. Several studies have demonstrated that cannabinoids and their metabolites are detectable in human milk produced by mothers who use cannabis. Due to their physicochemical properties, cannabinoids are stored in adipose tissue, can easily reach the mammary gland, and can be secreted in milk. Moreover, cannabinoid receptors are present in adipocytes and mammary epithelial cells. The activation of these receptors directly modulates fatty acid metabolism, potentially causing changes in milk fatty acid profiles. Additionally, the endocannabinoid system is intimately connected to the endocrine system. As such, it is probable that interactions of exogenous cannabinoids with the endocannabinoid system might modify release of critical hormones (e.g., prolactin and dopamine) that regulate milk production and secretion. Nonetheless, few studies have investigated effects of cannabis use (including on milk production and composition) in lactating women. Additional research utilizing robust methodologies are needed to elucidate whether and how cannabis use affects human milk production and composition.

Hereditary hypomagnesemia with secondary hypocalcemia caused by a novel mutation in TRPM6 gene

OBJECTIVES

Hereditary hypomagnesemia with secondary hypocalcemia (HSH), which results from variations in the transient receptor potential melastatin 6 (TRPM6) genes, is a rare hereditary cause of extremely low serum magnesium levels. We describe an infant with triggered seizures due to hypomagnesemia and a novel mutation in TRPM6 gene was identified.

CASE PRESENTATION

A 10-month-old boy presented with multidrug resistant seizures, and axial hypotonia due to severe hypomagnesemia. Electroencephalography and neuroimaging of the patient was normal. He had a favorable outcome with magnesium supplement. In this study, the patient underwent clinical exome sequencing (CES) which detected a novel homozygous variant in the TRPM6 gene: NM_017662.5: c.5571-3C>G. After replacing his magnesium orally, he was free from seizures and had an encouraging outcome at the twelfth-month follow-up.

CONCLUSIONS

HSH often presents with developmental issues, treatment-resistant seizures, and increased neuromuscular excitability. Untreated hypomagnesemia can potentially be fatal and severely impair cognitive function. Clinical suspicion is essential for early diagnosis and treatment.

Deciphering temporal gene expression dynamics in multiple coral species exposed to heat stress: Implications for predicting resilience

Coral reefs are facing unprecedented threats due to global climate change, particularly elevated sea surface temperatures causing coral bleaching. Understanding coral responses at the molecular level is crucial for predicting their resilience and developing effective conservation strategies. In this study, we conducted a comprehensive gene expression analysis of four coral species to investigate their long-term molecular response to heat stress. We identified distinct gene expression patterns among the coral species, with laminar corals exhibiting a stronger response compared to branching corals. Heat shock proteins (HSPs) showed an overall decreasing expression trend, indicating the high energy cost associated with sustaining elevated HSP levels during prolonged heat stress. Peroxidases and oxidoreductases involved in oxidative stress response demonstrated significant upregulation, highlighting their role in maintaining cellular redox balance. Differential expression of genes related to calcium homeostasis and bioluminescence suggested distinct mechanisms for coping with heat stress among the coral species. Furthermore, the impact of heat stress on coral biomineralization varied, with downregulation of carbonic anhydrase and skeletal organic matrix proteins indicating reduced capacity for biomineralization in the later stages of heat stress. Our findings provide insights into the molecular mechanisms underlying coral responses to heat stress and highlight the importance of considering species-specific responses in assessing coral resilience. The identified biomarkers may serve as indicators of heat stress and contribute to early detection of coral bleaching events. These findings contribute to our understanding of coral resilience and provide a basis for future research aimed at enhancing coral survival in the face of climate change.

The Role of Cannabidiol in Liver Disease: A Systemic Review

Cannabidiol (CBD), a non-psychoactive phytocannabinoid abundant in Cannabis sativa, has gained considerable attention for its anti-inflammatory, antioxidant, analgesic, and neuroprotective properties. It exhibits the potential to prevent or slow the progression of various diseases, ranging from malignant tumors and viral infections to neurodegenerative disorders and ischemic diseases. Metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease (NAFLD), alcoholic liver disease, and viral hepatitis stand as prominent causes of morbidity and mortality in chronic liver diseases globally. The literature has substantiated CBD's potential therapeutic effects across diverse liver diseases in in vivo and in vitro models. However, the precise mechanism of action remains elusive, and an absence of evidence hinders its translation into clinical practice. This comprehensive review emphasizes the wealth of data linking CBD to liver diseases. Importantly, we delve into a detailed discussion of the receptors through which CBD might exert its effects, including cannabinoid receptors, CB1 and CB2, peroxisome proliferator-activated receptors (PPARs), G protein-coupled receptor 55 (GPR55), transient receptor potential channels (TRPs), and their intricate connections with liver diseases. In conclusion, we address new questions that warrant further investigation in this evolving field.

Tetrandrine downregulates TRPV2 expression to ameliorate myocardial ischemia/reperfusion injury in rats via regulation of cardiomyocyte apoptosis, calcium homeostasis and mitochondrial function

Our previous study has indicated that tetrandrine (TET) can target miR-202-5p to repress the activation of transient receptor potential vanilloid type 2 (TRPV2), eventually ameliorating the progression of myocardial ischemia/reperfusion injury (MI/RI). This study is aimed to further ascertain the detailed mechanisms between TET and TRPV2 in MI/RI pathogenesis. Here, a myocardial I/R injury rat model and a hypoxia-reoxygenation (H/R) model in rat myocardial cell line (H9C2 cells) were established. We reported that pronounced upregulation of TRPV2 was observed in I/R rats and H/R-induced H9C2 cells. Silencing of TRPV2 could improve cardiac function and myocardial injury, reduced infarction size, and promoted cardiomyocyte proliferation in I/R rats. In I/R rats or H/R-induced H9C2 cells, cardiomyocyte apoptosis was inhibited by knocking-down TRPV2. Meanwhile, the silenced TRPV2 or TET treatment ameliorated the damaged mitochondrial structure, mitigated ROS generation, restored the impaired ΔΨM, inhibited mPTP opening and alleviated Ca2+ overload in H/R-induced H9C2 cells. The results obtained from the overexpression of TRPV2 were contrary to those depicted above. Moreover, TET could downregulate TRPV2 expression, while the overexpression of TRPV2 could reverse the above protective effects of TET in H/R-induced H9C2 cells. The results indicated that TET may function as a TRPV2 blocking agent, thereby attenuating the progression of MI/RI through modulation of cardiomyocyte apoptosis, calcium homeostasis and mitochondrial function. These findings offer a theoretical foundation for potential clinical application of TET therapy in patients with MI/RI.

The Complex Interplay between Toxic Hallmark Proteins, Calmodulin-Binding Proteins, Ion Channels, and Receptors Involved in Calcium Dyshomeostasis in Neurodegeneration

Calcium dyshomeostasis is an early critical event in neurodegeneration as exemplified by Alzheimer's (AD), Huntington's (HD) and Parkinson's (PD) diseases. Neuronal calcium homeostasis is maintained by a diversity of ion channels, buffers, calcium-binding protein effectors, and intracellular storage in the endoplasmic reticulum, mitochondria, and lysosomes. The function of these components and compartments is impacted by the toxic hallmark proteins of AD (amyloid beta and Tau), HD (huntingtin) and PD (alpha-synuclein) as well as by interactions with downstream calcium-binding proteins, especially calmodulin. Each of the toxic hallmark proteins (amyloid beta, Tau, huntingtin, and alpha-synuclein) binds to calmodulin. Multiple channels and receptors involved in calcium homeostasis and dysregulation also bind to and are regulated by calmodulin. The primary goal of this review is to show the complexity of these interactions and how they can impact research and the search for therapies. A secondary goal is to suggest that therapeutic targets downstream from calcium dyshomeostasis may offer greater opportunities for success.

Site-Specific Transient Receptor Potential Channel Mechanisms and Their Characteristics for Targeted Chronic Itch Treatment

Chronic itch is a debilitating condition with limited treatment options, severely affecting quality of life. The identification of pruriceptors has sparked a growing interest in the therapeutic potential of TRP channels in the context of itch. In this regard, we provided a comprehensive overview of the site-specific expression of TRP channels and their associated functions in response to a range of pruritogens. Although several potent antipruritic compounds that target specific TRP channels have been developed and have demonstrated efficacy in various chronic itch conditions through experimental means, a more thorough understanding of the potential for adverse effects or interactions with other TRP channels or GPCRs is necessary to develop novel and selective therapeutics that target TRP channels for treating chronic itch. This review focuses on the mechanism of itch associated with TRP channels at specific sites, from the skin to the sensory neuron, with the aim of suggesting specific therapeutic targets for treating this condition.

Targeting TRP channels: recent advances in structure, ligand binding, and molecular mechanisms

Transient receptor potential (TRP) channels are a large and diverse family of transmembrane ion channels that are widely expressed, have important physiological roles, and are associated with many human diseases. These proteins are actively pursued as promising drug targets, benefitting greatly from advances in structural and mechanistic studies of TRP channels. At the same time, the complex, polymodal activation and regulation of TRP channels have presented formidable challenges. In this short review, we summarize recent progresses toward understanding the structural basis of TRP channel function, as well as potential ligand binding sites that could be targeted for therapeutics. A particular focus is on the current understanding of the molecular mechanisms of TRP channel activation and regulation, where many fundamental questions remain unanswered. We believe that a deeper understanding of the functional mechanisms of TRP channels will be critical and likely transformative toward developing successful therapeutic strategies targeting these exciting proteins. This endeavor will require concerted efforts from computation, structural biology, medicinal chemistry, electrophysiology, pharmacology, drug safety and clinical studies.

Genetically engineered HEK cells as a valuable tool for studying electroporation in excitable cells

Electric pulses used in electroporation-based treatments have been shown to affect the excitability of muscle and neuronal cells. However, understanding the interplay between electroporation and electrophysiological response of excitable cells is complex, since both ion channel gating and electroporation depend on dynamic changes in the transmembrane voltage (TMV). In this study, a genetically engineered human embryonic kidney cells expressing NaV1.5 and Kir2.1, a minimal complementary channels required for excitability (named S-HEK), was characterized as a simple cell model used for studying the effects of electroporation in excitable cells. S-HEK cells and their non-excitable counterparts (NS-HEK) were exposed to 100 µs pulses of increasing electric field strength. Changes in TMV, plasma membrane permeability, and intracellular Ca2+ were monitored with fluorescence microscopy. We found that a very mild electroporation, undetectable with the classical propidium assay but associated with a transient increase in intracellular Ca2+, can already have a profound effect on excitability close to the electrostimulation threshold, as corroborated by multiscale computational modelling. These results are of great relevance for understanding the effects of pulse delivery on cell excitability observed in context of the rapidly developing cardiac pulsed field ablation as well as other electroporation-based treatments in excitable tissues.

The Role of TRPM7 in Oncogenesis

This review summarizes the current understanding of the role of transient receptor potential melastatin-subfamily member 7 (TRPM7) channels in the pathophysiology of neoplastic diseases. The TRPM family represents the largest and most diverse group in the TRP superfamily. Its subtypes are expressed in virtually all human organs playing a central role in (patho)physiological events. The TRPM7 protein (along with TRPM2 and TRPM6) is unique in that it has kinase activity in addition to the channel function. Numerous studies demonstrate the role of TRPM7 chanzyme in tumorigenesis and in other tumor hallmarks such as proliferation, migration, invasion and metastasis. Here we provide an up-to-date overview about the possible role of TRMP7 in a broad range of malignancies such as tumors of the nervous system, head and neck cancers, malignant neoplasms of the upper gastrointestinal tract, colorectal carcinoma, lung cancer, neoplasms of the urinary system, breast cancer, malignant tumors of the female reproductive organs, prostate cancer and other neoplastic pathologies. Experimental data show that the increased expression and/or function of TRPM7 are observed in most malignant tumor types. Thus, TRPM7 chanzyme may be a promising target in tumor therapy.

A Comprehensive Review on the Regulatory Action of TRP Channels: A Potential Therapeutic Target for Nociceptive Pain

The transient receptor potential (TRP) superfamily of ion channels in humans comprises voltage-gated, non-selective cation channels expressed both in excitable as well as non-excitable cells. Four TRP channel subunits associate to create functional homo- or heterotetramers that allow the influx of calcium, sodium, and/or potassium. These channels are highly abundant in the brain and kidney and are important mediators of diverse biological functions including thermosensation, vascular tone, flow sensing in the kidney and irritant stimuli sensing. Inherited or acquired dysfunction of TRP channels influences cellular functions and signaling pathways resulting in multifaceted disorders affecting skeletal, renal, cardiovascular, and nervous systems. Studies have demonstrated the involvement of these channels in the generation and transduction of pain. Based on the multifaceted role orchestrated by these TRP channels, modulation of the activity of these channels presents an important strategy to influence cellular function by regulating intracellular calcium levels as well as membrane excitability. Therefore, there has been a remarkable pharmaceutical inclination toward TRP channels as therapeutic interventions. Several candidate drugs influencing the activity of these channels are already in the clinical trials pipeline. The present review encompasses the current understanding of TRP channels and TRP modulators in pain and pain management.

The versatility of the putative transient receptor potential ion channels in regulating the calcium signaling in Aspergillus nidulans

IMPORTANCE

Transient receptor potential (TRP) ion channels are evolutionarily conserved integral membrane proteins with non-selective ion permeability, and they are widely distributed in mammals and single-cell yeast and serve as crucial mediators of sensory signals. However, the relevant information concerning TRP channels in Aspergillus nidulans remains inadequately understood. In this study, by gene deletion, green fluorescent protein tagging, and cytosolic Ca2+ transient monitoring techniques, the biological functions of three potential TRP channels (TrpA, TrpB, and TrpC) have been explored for which they play distinct and multiple roles in hyphal growth, conidiation, responsiveness to external stress, and regulation of intracellular Ca2+ homeostasis. The findings of this study on the functions of potential TRP channels in A. nidulans may serve as a valuable reference for understanding the roles of TRP homologs in industrial or medical strains of Aspergillus, as well as in other filamentous fungi.

Membrane-anchored calpains - hidden regulators of growth and development beyond plants?

Calpains are modulatory proteases that modify diverse cellular substrates and play essential roles in eukaryots. The best studied are animal cytosolic calpains. Here, we focus on enigmatic membrane-anchored calpains, their structural and functional features as well as phylogenetic distribution. Based on domain composition, we identified four types of membrane-anchored calpains. Type 1 and 2 show broad phylogenetic distribution among unicellular protists and streptophytes suggesting their ancient evolutionary origin. Type 3 and 4 diversified early and are present in brown algae and oomycetes. The plant DEK1 protein is the only representative of membrane-anchored calpains that has been functionally studied. Here, we present up to date knowledge about its structural features, putative regulation, posttranslational modifications, and biological role. Finally, we discuss potential model organisms and available tools for functional studies of membrane-anchored calpains with yet unknown biological role. Mechanistic understanding of membrane-anchored calpains may provide important insights into fundamental principles of cell polarization, cell fate control, and morphogenesis beyond plants.

The Effects of Carvacrol on Transient Receptor Potential (TRP) Channels in an Animal Model of Parkinson's Disease

In this study, we aimed to investigate the effects of carvacrol (CA), a widely used phytochemical having anti-oxidant and neuroprotective effects, on transient receptor potential (TRP) channels in an animal model of Parkinson's disease (PD). A total of 64 adult male Spraque-Dawley rats were divided into four groups: sham-operated, PD animal model (unilateral intrastriatal injections of 6-hydroxydopamine (6-OHDA), 6 µg/µl), PD + vehicle (dimethyl sulfoxide (DMSO)) treatment, and PD + CA treatment (10 mg/kg, every other day, for 14 days). Half of the brain samples of substantia nigra pars compacta (SNpc) and striatum (CPu) were collected for immunohistochemistry and the remaining half were used for molecular analyses. CA treatment significantly increased the density of dopaminergic neurons immunolabeled with tyrosine hydroxylase and transient receptor potential canonical 1 (TRPC1) channel in the SNpc of PD animals. In contrast, the density of astrocytes immunolabeled with glial fibrillary acetic acid and transient receptor potential ankyrin 1 (TRPA1) channel significantly decreased following CA treatment in the CPu of PD animals. RT-PCR and western blot analyses showed that 6-OHDA administration significantly reduced TRPA1 and TPRPC1 mRNA expression and protein levels in both SNpc and CPu. CA treatment significantly upregulated TRPA1 expression in PD group, while TRPC1 levels did not display an alteration. Based on this data it was concluded that CA treatment might protect the number of dopaminergic neurons by reducing the reactive astrogliosis and modulating the expression of TRP channels in both neurons and astrocytes in an animal model of PD.

The Molecular Mechanisms Responsible for Tear Hyperosmolarity-Induced Pathological Changes in the Eyes of Dry Eye Disease Patients

Dry eye disease (DED) is a multifactorial disorder of the lacrimal system and ocular surface, characterized by a deficiency in the quality and/or quantity of the tear fluid. The multifactorial nature of DED encompasses a number of interconnected underlying pathologies, including loss of homeostasis, instability and hyperosmolarity of the tears, and the induction and propagation of detrimental inflammatory responses in the eyes, which finally results in the development of neurosensory dysfunction and visual disruption. Dryness, grittiness, scratchiness, discomfort, inflammation, burning, watering, ocular fatigue, pain, and decreased functional visual acuity are common symptoms of DED. Eye dysfunction drastically attenuates patients' quality of life. Accordingly, a better understanding of the pathogenic processes that regulate the development and progression of DED is crucially important for the establishment of new and more effective DED-related treatment approaches, which would significantly improve the quality of life of DED patients. Since the process of osmoregulation, which guards the ocular surface epithelia and maintains normal vision, is affected when the osmolarity of the tears is greater than that of the epithelial cells, tear hyperosmolarity (THO) is considered an initial, important step in the development, progression, and aggravation of DED. In order to delineate the role of THO in the pathogenesis of DED, in this review article, we summarize current knowledge related to the molecular mechanisms responsible for the development of THO-induced pathological changes in the eyes of DED patients, and we briefly discuss the therapeutic potential of hypo-osmotic eye drops in DED treatment.