Channel Expression Research Articles

Plants breathing under pressure: mechanistic insights into soil compaction-induced physiological, molecular and biochemical responses in plants.

This review highlights the molecular, biochemical and physiological responses of plants under soil compaction and presents suitable strategies for optimizing soil compaction for sustainable and intelligent plant production. Soil compaction (SC) increases the mechanical impedance of agricultural crops, which restricts plant growth, root elongation, and productivity. Therefore, exploring the impacts of SC-induced alterations in plants and developing optimization strategies are crucial for sustainable agricultural production and ensuring global food security. However, the regulation of molecular, biochemical and physiological responses to SC in plants has not yet been well explored. Here, we conducted a thorough analysis of the relevant literature regarding the primary factors behind SC in agricultural soils, mechanistic insights into SC-mediated molecular and physiological alterations in plants, the impact of SC on plant productivity, and SC-minimization strategies for eco-friendly and intelligent agricultural production. The existing information suggests that plant roots sense SC-induced changes in soil properties, including decreased soil water content, hypoxia, nutrient deficiency and mechanical stimuli, through altering the expression of membrane-located ion channel- or stimulus receptor-related genes, such as MSLs, MCA1, and AHK. After signal transduction, the synthesis and transport of several plant hormones, mainly ABA, ethylene and auxin, change and restrict root deepening but promote root thickening. In addition, the changes in plant hormones in combination with decreased water availability and decreased root hydraulic conductance induced by SC affect aboveground physiological responses, such as decreasing leaf hydraulic conductance, promoting stomatal closure and inhibiting plant photosynthesis. Comprehensive physiological insights into SC in plants and SC optimization strategies could be useful to soil biologists and plant eco-physiologists seeking to improve soil management and sustainable agricultural plant production to promote global food security.

The effect of modulation Piezo2 by IGF-1 on tactile hypersensitivity in BTBR model mice.

Autism spectrum disorder (ASD) is classified as a neurodevelopmental disorder. Individuals with ASD exhibit a higher incidence of tactile hypersensitivity. However, the underlying mechanisms remain unclear. The dorsal root ganglion (DRG) plays a crucial role in influencing tactile processing. This study aims to integrate RNA sequencing (RNA-seq) and molecular biology experiments to identify key molecules involved in tactile hypersensitivity in ASD, further investigate related mechanisms, and develop effective intervention strategy. Using BTBR as the ASD model mouse and wild-type C57BL/6J as the control mouse, the differences in tactile sensitivity between them was compared. DRG were collected for RNA-seq analysis. Immunofluorescence and Enzyme-linked immunosorbent assay (ELISA) techniques were employed to validate the identified key molecules. And combined western blot to investigate the associated regulatory pathways. BTBR mice exhibit tactile hypersensitivity, which are associated with the upregulation of IGF-1 in the DRG. IGF-1 regulates the expression of Piezo2 ion channels. Inhibition of the IGF-1/Piezo2 pathway can significantly alleviate tactile hypersensitivity and social deficits in BTBR mice. Additionally, gentle touch intervention has been shown to reduce the overexpression of IGF-1/Piezo2 in the DRG, thereby ameliorating ASD symptoms. The upregulation of the IGF-1/Piezo2 pathway in DRG may serve as a potential mechanism for tactile hypersensitivity observed in BTBR mice. Restoring the normalization of the IGF-1/Piezo2 is crucial for alleviating tactile hypersensitivity and synergistically rescues social deficits. Gentle touch intervention has the potential to ameliorate these behaviors through regulating IGF-1/Piezo2, positioning it as a promising strategy for ASD.

Mechanisms of chronic postsurgical pain

Chronic pain after surgery, also known as chronic postsurgical pain (CPSP), is recognized as a significant public health issue with serious medical and economic consequences. Current research on CPSP underscores...

Evaluation of immunohistochemical TRPC3 and TRPC6 expression patterns in human endometriosis.

Although to date the pathogenesis of endometriosis remains largely unexplained, it is known that processes of migration, proliferation and revascularization and thus calcium as a messenger substance play an important role. Consecutively, the present study examines the immunohistochemical expression of the calcium transient receptor potential channels 3 and 6 (TRPC3 and TRPC6) in ectopically located (outside the uterine cavity) endometrial tissue. Laparoscopically collected and histomorphologically verified endometriosis tissues from several different intraabdominal locations were examined (n = 20) and immunohistochemical stainings were performed with anti-TRPC3 and anti-TRPC6 antibodies (Alomone Labs, Jerusalem). Hereby, eutopic endometrium served as a healthy control cohort (n = 6). Staining patterns were evaluated using a modified immunoreactive score (IRS) and exploratory statistical analysis was performed, aiming to determine relations of staining intensities with associated clinical parameters such as rASRM stage and location. We determined a strong cytoplasmatic TRPC3 and TRPC6 expression in all ectopic endometrial glandular formations, albeit with focally varying staining intensities. Within our cohort, we did not verify a statistically significant difference of TRPC3 and TRPC6 expression between endometriosis patients and a healthy control group or between different clinical affections (rASRM stages). Our study confirms - to our knowledge for the first time - the successful immunohistochemical assessment of TRPC3 and TRPC6 in endometriosis, setting the basis for future studies aiming at evaluating not only clinical aspects of TRPC3 and TRPC6 expression but also shedding light on its function in the pathophysiological context of endometriosis.

Modulatory roles of capsaicin on thermogenesis in C2C12 myoblasts and the skeletal muscle of mice.

Capsaicin, a polyphenol, is known to regulate energy expenditure and thermogenesis in adipocytes and muscles. However, its role in modulating uncoupling proteins (UCPs) and adenosine triphosphate (ATP)-dependent thermogenesis in muscles remains unclear. This study investigated the mechanisms underlying the role of capsaicin in modulating the UCP- and ATP-dependent thermogenesis in C2C12 myoblasts, as well as the gastrocnemius (GM) and soleus muscles (SM) of mice. We employed molecular dynamics (MD), quantitative real-time polymerase chain reactions (qRT-PCR), immunoblots, staining methods, and assay kits to investigate the role of capsaicin on thermogenesis and its modulatory roles on the transient receptor potential cation channel subfamily V member 1 (TRPV1) and α-/β-adrenergic receptors (ARs) using in vitro and in vivo models. Our findings demonstrate that capsaicin treatment in high-fat diet-induced obese mice reduces weight gain and elevates the expression of UCP- and ATP-dependent thermogenic effectors through ATP-consuming calcium and creatine futile cycles. In vitro and in vivo models capsaicin treatment elevated the expression of sarcoendoplasmic/endoplasmic reticulum calcium ATPases (SERCA-1 and -2), ryanodine receptors (RYR-1 and -2), uncoupling proteins (UCP-2 and -3), creatine kinase B (CKB), and creatine kinase mitochondrial 2 (CKMT2), through activation of TRPV1, α1-, β2-, and β3-AR as well as the suppressed expression of α2-AR. Furthermore, our results also indicate that capsaicin promotes myotube development and enhances lipid metabolism in C2C12cells. We found that capsaicin increased intracellular Ca2+ levels and the expression of the voltage-dependent anion channel (VDAC) and mitochondrial calcium uniporter (MCU), suggesting that elevated mitochondrial Ca2+ levels boost the expression of oxidative phosphorylation protein complexes via the activation of the ATP-futile cycle. Mechanistic studies in C2C12cells revealed that TRPV1 is likely dispensable for capsaicin-induced thermogenesis, and TRPV1 and α1-AR may synergistically induce thermogenesis. Collectively, our findings have uncovered a novel mechanism of UCP- and ATP-dependent thermogenesis and its associated pathways in both cellular and animal models which is crucial for designing therapeutic strategies to address obesity and associated metabolic diseases.

Intestinal barrier function declines during polycystic kidney disease progression.

Most patients with autosomal dominant polycystic kidney disease (ADPKD) develop kidney cysts due to germline PKD1 mutations. In the kidney, Pkd1 loss impairs epithelial cell integrity and increases macrophage infiltration, contributing to cyst growth. Despite its role as the body's largest inflammatory cell reservoir, it has yet to be elucidated whether a similar phenotype presents in the intestines. We hypothesize that loss of Pkd1 leads to a leaky intestinal epithelial barrier and increased inflammation, before rapid cystogenesis. Control and inducible, global Pkd1 knockout (Pkd1KO) mice were euthanized at 3 and 6 mo of age (early and late stage) to evaluate kidney disease progression, small and large intestinal integrity, and inflammation. Early-stage Pkd1KO mice displayed mild cystic kidneys and tubular injury with preserved kidney function. Intestinal epithelial barrier was tighter in KO mice, which was associated with higher expression of cell-cell epithelial integrity markers. However, there was no evidence of local or systemic inflammation in either genotype. Late-stage Pkd1KO mice had severely cystic, impaired kidneys with increased expression of integrity markers, tubular injury, and inflammation. Intestinal epithelial barrier was leakier in late-stage Pkd1KO mice, accompanied by gene reduction of integrity markers, increased inflammation, and elevated water and sodium channel expression. Gut motility and fecal water excretion were increased in Pkd1KO compared with flox mice irrespective of age. Overall, kidney injury appears to precede intestinal injury in ADPKD, whereby the intestinal barrier becomes leaky as cystogenesis progresses.NEW & NOTEWORTHY Though autosomal dominant polycystic kidney disease (ADPKD) is a multisystem disorder, this is the first study to explore a kidney-gut contribution to disease progression. We identified a tightened intestinal epithelial barrier in early PKD, which becomes leaky as kidneys become more cystic, accompanied by a sustained loss of fecal water. Given the only approved ADPKD therapeutic yields adverse aquaretic events, this study emphasizes the need to evaluate extrarenal water loss in patients before prescribing.

Chewing-Activated TRPV4/PIEZO1-HIF-1α-Zn Axes in a Rat Periodontal Complex.

The upstream mechanobiological pathways that regulate the downstream mineralization rates in periodontal tissues are limitedly understood. Herein, we spatially colocalized and correlated compression and tension strain profiles with the expressions of mechanosensory ion channels (MS-ion) TRPV4 and PIEZO1, biometal zinc, mitochondrial function marker (MFN2), cell senescence indicator (p16), and oxygen status marker hypoxia-inducible factor-1α (HIF-1α) in rats fed hard and soft foods. The observed zinc and related cellular homeostasis in vivo were ascertained by TRPV4 and PIEZO1 agonists and antagonists on human periodontal ligament fibroblasts ex vivo. Four-week-old male Sprague-Dawley rats were fed hard (n = 3) or soft (n = 3) foods for 4 wk (in vivo). Significant changes in alveolar socket and root shapes with decreased periodontal ligament space and increased cementum volume fraction were observed in maxillae on reduced loads (soft food). Reduced loads impaired distally localized compression-stimulated PIEZO1 and mesially localized tension-stimulated TRPV4, decreased mitochondrial function (MFN2), and increased cell senescence in mesial and distal periodontal regions. The switch in HIF-1α from hard food-distal to soft food-mesial indicated a plausible effect of shear-regulated blood and oxygen flows in the periodontal complex. Blunting or activating TRPV4 or PIEZO1 MS-ion channels by channel-specific antagonists or agonists in human periodontal ligament fibroblast cultures (in vitro) indicated a positive correlation between zinc levels and zinc transporters but not with MS-ion channel expressions. The effects of reduced chewing loads in vivo were analogous to TRPV4 and PIEZO1 antagonists in vitro. Study results collectively illustrated that tension-induced TRPV4 and compression-induced PIEZO1 activations are necessary for cell metabolism. An increased hypoxic state with reduced functional loads can be a conducive environment for cementum growth. From a practical standpoint, dose rate-controlled loads can modulate tension and compression-specific MS-ion channel activation, cellular zinc, and HIF-1α transcription. These mechanobiochemical events indicate the plausible catalytic role of biometal zinc in mineralization, periodontal maintenance, and dentoalveolar joint function.

Modeling ocular surface ion and water transport by generation of lipid- and mucin-producing human Meibomian gland and conjunctival epithelial cells.

Despite the importance of ocular surface in human physiology and diseases, little is known about ion channel expression, properties and regulation in ocular epithelial cells. Furthermore, human primary epithelial cells have rarely been studied in favor of rat, mouse and especially rabbit animal models. Here, we developed primary human Meibomian gland (hMGEC) and conjunctival (hConEC) epithelial cells. We show that hConEC and hMGEC produce MUC5AC and lipids, respectively. With cell cultures maintained at the air-liquid interface, we recorded transepithelial short-circuit currents by the Ussing chamber method. We identified in the apical membrane Na+, Cl- and K+ ion channels; amiloride-sensitive ENaC, cAMP-dependent CFTR, UTP-dependent TMEM16a, and chromanol 293B-sensitive KCNQ1. At the basolateral membrane we identified bumetanide-sensitive NKCC and barium-sensitive K+ channels. We also found that VIP, concentration-dependent (EC50 of 1-8 nM), stimulates the CFTR-dependent Isc in both cells. Western blot analysis confirms the expression in both cell cultures of βENaC subunit, CFTR, TMEM16a and KCNQ1 proteins. We recorded water influx by quantitative phase microscopy and identified a cAMP-dependent and mercury sensitive water flux and identified by western blot AQP3 and AQP5 proteins in hConEC and hMGEC. Taken together, we propose a model of the ion transports of human conjunctival and Meibomian gland epithelial cells that will set the stage for a future molecular dissection of the regulation of these transport proteins in the context of tear secretion and related diseases.

Leiurus quinquestriatus venom-gold nanoparticle conjugates: a novel approach for modulating ion channel gene expression in liver cancer

ABSTRACT Hepatocellular carcinoma (HCC) is a highly aggressive malignancy with limited treatment options and a poor prognosis. Scorpion venoms have shown promising anticancer activity, but achieving optimal bioavailability and targeted delivery to tumors remains a challenge. This study investigated the antitumor effects of Leiurus quinquestriatus scorpion venom conjugated with gold nanoparticles (GNPs-V) against HepG2 and Huh-7 human liver cancer cell lines, aiming to downregulate the overexpressed ion channels TRPC6 and TRPV2. Venom was extracted from L. quinquestriatus scorpions and conjugated to citrate-capped gold nanoparticles (GNPs) through incubation. GNPs-V displayed potent cytotoxicity (IC50 ~ 1.2 μg/mL), surpassing that of the unconjugated venom in both cell lines. Wound healing assays showed significant inhibition of cancer cell migration and proliferation by GNPs-V. Flow cytometry revealed that, while venom induced G1 cell cycle arrest in HepG2 cells and G2/M arrest in Huh-7 cells, GNPs-V replicated these effects, indicating that the venom’s mechanism remained dominant. Notably, GNPs-V induced significantly higher levels of apoptosis compared to unconjugated venom. Additionally, GNPs-V more effectively downregulated the expression of TRPC6 and TRPV2 than venom alone. In conclusion, conjugating L. quinquestriatus venom with GNPs enhanced its selective cytotoxicity against liver cancer cells, inhibited migration, induced cell cycle arrest, promoted apoptosis, and modulated the expression of aberrantion channels.

OP25 Young Researcher Award: Lymphocytic colitis can be transcriptionally divided into channelopathic and inflammatory lymphocytic colitis

Abstract Background The pathobiology of the moderate/non-destructive inflammatory bowel disease (IBD) lymphocytic colitis (LC) is poorly understood. We aimed to define an LC-specific mucosal transcriptome to gain insight into LC pathology, identify unique genomic signatures, and uncover potentially druggable disease pathways. Methods We performed bulk RNA-sequencing of LC and collagenous colitis (CC) colonic mucosa from patients with active disease, and healthy controls (n=4-10 per cohort). Differential gene expression was analyzed by gene-set enrichment and deconvolution analyses to identify pathologically relevant pathways and cells, respectively, altered in LC. Key findings were validated using reverse transcription quantitative PCR and/or immunohistochemistry. Finally, we compared our data to a previous cohort of ulcerative colitis and Crohn’s disease patients (n=4 per group) to distinguish non-destructive from classic IBD. Results LC can be subdivided into channelopathic LC, which is governed by organic acid and ion transport dysregulation; and inflammatory LC, which is driven by microbial immune responses. Inflammatory LC displays an innate and adaptive immunity that is limited compared to CC and classic IBD. Conversely, we noted a distinct induction of regulatory non-coding RNA species in inflammatory LC samples. Moreover, compared to CC, water channel and cell adhesion molecule gene expression decreased in channelopathic LC, whereas it was accentuated in inflammatory LC and associated with reduced intestinal epithelial cell proliferation. Conclusion We conclude that LC can be subdivided into channelopathic LC and inflammatory LC that could be pathomechanistically distinct subtypes despite their shared clinical presentation. Inflammatory LC exhibits a dampened immune response compared to CC and classic IBDs. Our results point to regulatory micro-RNAs as a potential disease-specific feature that may be amenable to therapeutic intervention.

The Role of TRPM2 Channel in Doxorubicin-induced Cell Damage in Laryngeal Squamous Cancer Cells.

Laryngeal squamous cell carcinoma is a common type of head and neck cancer. This study investigated the role of the TRPM2 channel in doxorubicin (DOX)-induced cell damage in human laryngeal squamous cancer cells (Hep-2). Cells were exposed to various DOX concentrations and the appropriate dose was found. Then, TRPM2 antagonist ACA was treated. At the end of the study, cell viability test, Western blot and oxidative stress and inflammatory markers were examined. The results showed that TRPM2 channel expression increased with DOX administration, and DOX incubation in cells caused an increase in ROS, MDA, IL-1β, IL-6, and TNF-α levels, while GSH and GSH-Px levels decreased. Concurrent treatment with ACA attenuated these effects and reduced oxidative stress and inflammation. In addition, DOX-induced apoptosis markers including Casp-3, Casp-8, Casp-9, p53, and Bax were elevated, while Bcl-2 levels were decreased; ACA treatment reversed these changes. The study demonstrated that DOX treatment significantly enhances TRPM2 channel activation and ROS production in Hep-2 cells, thereby initiating apoptotic pathways that lead to cell death. Consequently, targeting the TRPM2 channel may represent a promising therapeutic strategy for treating laryngeal cancer.

Distinct cell types along thick ascending limb express pathways for monovalent and divalent cation transport.

Kidney thick ascending limb cells reabsorb sodium, potassium, calcium, and magnesium and contribute to urinary concentration. These cells are typically viewed as of a single type that recycles potassium across the apical membrane and generates a lumen-positive transepithelial voltage driving calcium and magnesium reabsorption, although variability in potassium channel expression has been reported. Additionally, recent transcriptomic analyses suggest that different cell types exist along this segment, but classifications have varied and have not led to a new consensus model. We used immunolocalization, electrophysiology and enriched single nucleus RNA-Seq to identify thick ascending limb cell types in rat, mouse and human. We identified three major TAL cell types defined by expression of potassium channels and claudins. One has apical potassium channels, low basolateral potassium conductance, and is bordered by a sodium-permeable claudin. A second lacks apical potassium channels, has high basolateral potassium conductance and is bordered by calcium- and magnesium-permeable claudins. A third type also lacks apical potassium channels and has a high basolateral potassium conductance, but these cells are ringed by sodium-permeable claudins. The recognition of diverse cell types resolves longstanding questions about how solute transport can be modulated selectively and how disruption of these cells leads to human disease.

TRPM4 contributes to cell death in prostate cancer tumor spheroids, and to extravasation and metastasis in a zebrafish xenograft model system.

Transient receptor potential melastatin-4 (TRPM4) ion channel expression is upregulated in prostate cancer (PCa), contributing to increased cell proliferation, migration, adhesion, epithelial-to-mesenchymal transition, cell cycle shift, and alterations of intracellular Ca2+ signaling. GEO2R platform analysis of messenger RNA (mRNA) expression of ~ 6350 genes in normal and malignant prostate tissue samples from 15 PCa patients demonstrates that TRPM4 expression is upregulated sixfold and is among the most significantly upregulated genes in PCa. We find that absence of TRPM4 reduced PCa tumor spheroid size and decreased PCa tumor spheroid outgrowth. In addition, lack of TRPM4 increased cell death in PCa tumor spheroids, a phenotype that is absent in two-dimensional (2D) cancer cell systems. Lastly, absence of TRPM4 in PCa cells reduced extravasation and metastatic burden in a preclinical zebrafish cancer model. Taken together, our findings show that TRPM4 is an attractive therapeutic target in PCa and highlights the need for future development of pharmacological tools.

Influence of Enterococcus faecium, a probiotic component, on ion channels in colon cancer

Aims: This study aimed to investigate the effect of probiotic bacterium Enterococcus faecium (E. faecium) on the gene expression of ion channels in colon cancer cells. Methods: The cytotoxic effect on SW480 colon cancer cell line was analyzed by MTT cell proliferation test using E. faecium bacterial cell culture free supernatants. The effect of E. faecium on ion channel genes in SW480 cells was determined by qRT PCR analysis. STRING analysis was used to reveal protein-protein interactions of ion channel proteins. Bioinformatic analysis of healthy and colon cancer patient data on ion channels was revealed with GEPIA platform. Results: The SW480 cell line's viability was enhanced by E. fecieum bacterial cell culture free supernatants dosages of 0.5 and 1.09 mg/ml, but it dramatically declined between 2.187 and 17.5 mg/ml doses, according the MTT study. Analysis of gene expression revealed that the TRPV2 and TRPM8 genes had significantly increased. The examined ion channel proteins were discovered to be substantially linked to one another based on STRING analysis. The TRPM2 gene we looked at revealed a notable rise in colon cancer patients based on data from both healthy and colon cancer patients on the GEPIA platform. Conclusion: E. faecium has been shown to have many beneficial effects on health. Our study has shown that it also has an effect on ion channels in cancer cells and that ion channels are of great importance for cell survival and death.

The Molecular Biology of Placental Transport of Calcium to the Human Foetus.

From fertilisation to delivery, calcium must be transported into and within the foetoplacental unit for intracellular signalling. This requires very rapid, precisely located Ca2+ transfers. In addition, from around the eighth week of gestation, increasing amounts of calcium must be routed directly from maternal blood to the foetus for bone mineralisation through a flow-through system, which does not impact the intracellular Ca2+ concentration. These different processes are mediated by numerous membrane-sited Ca2+ channels, transporters, and exchangers. Understanding the mechanisms is essential to direct interventions to optimise foetal development and postnatal bone health and to protect the mother and foetus from pre-eclampsia. Ethical issues limit the availability of human foetal tissue for study. Our insight into the processes of placental Ca2+ handling is advancing rapidly, enabled by developing genetic, analytical, and computer technology. Because of their diverse sources, the reports of new findings are scattered. This review aims to pull the data together and to highlight areas of uncertainty. Areas needing clarification include trafficking, membrane expression, and recycling of channels and transporters in the placental microvilli; placental metabolism of vitamin D in gestational diabetes and pre-eclampsia; and the vascular effects of increased endothelial Orai expression by pregnancy-specific beta-1-glycoproteins PSG1 and PSG9.

Respiratory surveillance and inward rectifier potassium channel expression in lung tissue within an experimental epilepsy model.

Epilepsy is characterized by neuronal discharges that occur as a result of disruption of the excitatory and inhibitory balance of the brain due to functional and structural changes. It has been shown in the literature that this neurological disorder may be related to the expression of ion channels. Any defect in the function or expression mechanism of these channels can lead to various neuronal disorders such as epilepsy. Epileptic seizures occur as a result of the accumulation of biological disorders in the circulatory, respiratory and nervous systems. In this study, we aimed to examine the changes in the expression of inward-directing potassium channels (Kir 3.1 and 6.2) in lung tissue and respiratory functions, considering that it will contribute to the elucidation of the mechanisms of sudden deaths thought to be caused by cardiorespiratory complications in epilepsy. In the study, 48 adult male Wistar albino rats weighing 250-300g were used in the study. During the research process, respiratory function tests were performed on epileptic rats induced with pentylenetetrazol (PTZ) firing model, and then histopathological changes in lung and hippocampus tissues, and expression levels of the Kir (3.1 and 6.2) channels were evaluated by immunohistochemistry, qRT-PCR and Western blot analysis. Memantine and tertiapin-Q have been shown to protect epileptic groups from histopathological harm induced by PTZ application and also reduce HIF-1α, Kir 3.1 and Kir 6.2 expression. The findings imply that memantine and tertiapin-Q would be suitable options for treating epilepsy patients.

Dominant spoilage bacteria in crayfish alleviate ultrasonic stress through mechanosensitive channels but could not prevent the process of membrane destruction

Although there have been many studies on the efficacy of ultrasonic inactivation, the stress resistance mechanism of bacteria is still a challenge for complete ultrasonic inactivation. In this study, the dominant spoilage bacteria in crayfish, Shewanella baltica (S. baltica) and Aeromonas veronii (A. veronii), were subjected to high-intensity ultrasonic treatment. The results showed compromised cell membrane, decreased membrane fluidity, hyperpolarized membrane potential, and disrupted succinate-coenzyme Q reductase. Transmission electron microscopy revealed significant fragmentation of S. baltica, whereas A. veronii, with its thick cell wall and outer capsule membrane, demonstrated enhanced resistance to ultrasound. Real-time quantitative PCR indicated that in response to ultrasonic stress, bacteria initiated a stress response mechanism by increasing the expression of mechanosensitive channels; meanwhile, the outer capsule of A. veronii delayed the transformation of ultrasonic external forces into cell membrane stress. The study found that in response to ultrasonic stress, bacteria initiated a stress response mechanism by increasing the expression of mechanosensitive channels as "emergency valve" in short time but could not prevent the process of membrane destruction with prolonged exposure. This finding provided a basis for addressing bacterial stress tolerance in ultrasonic inactivation.

Evaluation of the Cardiotoxicity of Echinochrome A using Human Induced Pluripotent Stem Cell-derived Cardiac Organoids

Echinochrome A (EchA), a marine-derived natural product, has shown promise in treating cardiovascular and inflammatory diseases due to its antioxidant and anti-inflammatory properties. However, its cardiac safety remains underexplored. In this study, we utilized human induced pluripotent stem cell-derived cardiac organoids (hCOs) to validate their ability to model the cardiac safety profile of EchA in a human-relevant system. While EchA's therapeutic effects have been reported, prior studies have not evaluated its cardiotoxicity or arrhythmogenic potential in a high-fidelity 3D human cardiac model. The hCOs, characterized by expression of key cardiac markers (cTnT) and functional ion channels (Cav1.2, Nav1.5, hERG), exhibited structural and electrophysiological properties reflective of human cardiac physiology. Using multi-electrode array (MEA) analysis, we assessed the effects of EchA at concentrations ranging from 0.1 to 30 µM on electrophysiological parameters, including beat period, field potential amplitude, field potential duration, and spike slope. EchA treatment induced no significant changes in these parameters, confirming its non-toxic electrophysiological profile. Cellular viability and lactate dehydrogenase (LDH) assays revealed no cytotoxic effects of EchA across tested concentrations. Contractility assays further demonstrated that EchA did not affect contraction velocity, relaxation velocity, or time to 50 % maximal contraction and relaxation. This study fills a critical gap and highlights the translational relevance of hCOs for cardiotoxicity assessment, demonstrating EchA's cardiac safety and supporting its potential therapeutic and environmental applications.

Targeting ion channels: innovative approaches to combat cancer drug resistance.

Ion channels, as functional molecules that regulate the flow of ions across cell membranes, have emerged as a promising target in cancer therapy due to their pivotal roles in cell proliferation, metastasis, apoptosis, drug resistance, and so on. Recently, increasing evidence suggests that dysregulation of ion channels is a common characteristic of cancer cells, contributing to their survival and the resistance to conventional therapies. For example, the aberrant expression of sodium (Na+) and potassium ion (K+) channels is significantly correlated with the sensitivity of chemotherapy drugs. The endogenous calcium (Ca2+) channels contribute to the acquired resistance of osimertinib in epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer cell lines. Ferrous ions (Fe2+) enhance the sensitivity of breast cancer cells to doxorubicin treatment. Preclinical models have also demonstrated the effect of specific ion channel blockers or modulators on anticancer drug resistance. This review describes the current understanding about the interaction between ion channels and the therapeutic efficacy of anticancer drugs. Then, the therapeutic potential of ion channel blockers or modulators in enhancing the sensitivity or overcoming the resistance of cancer cells to anticancer therapies is discussed. Targeting ion channels will hopefully offer a novel and promising strategy for overcoming cancer drug resistance.

VDAC1-NF-κB/p65-mediated S100A16 contributes to myocardial ischemia/reperfusion injury by regulating oxidative stress and inflammatory response via Calmodulin/CaMKK2/AMPK pathway

Myocardial injury triggers intense inflammatory reactions and oxidative stress responses. S100 calcium-binding protein A16 (S100A16), a multi-functional calcium (Ca2+)-binding protein, participates in inflammatory responses and contributes to ischemia/reperfusion (I/R) injury. Nevertheless, the precise mechanism by which S100A16 operates in myocardial I/R injury remains uncertain. Cardiac I/R injury was produced by ligation/release of the left anterior descending artery, and mouse cardiac cells were subjected to hypoxia/reoxygenation (H/R) to determine the biological effects in vitro. We demonstrated that S100A16 was upregulated in the ischemic hearts and cardiac cells after I/R and H/R injury. Adenovirus-mediated S100A16 inhibition led to a considerable improvement in cardiac function with a reduced infarct size, accompanied by a reduction in cardiomyocyte apoptosis. Similar effects of S100A16 inhibition on inflammation and reactive oxygen species (ROS) production were observed in cultured cardiomyocytes. Importantly, we showed that I/R and H/R treatment upregulated the expression of voltage-dependent anion channel 1 (VDAC1), which subsequently activated NF-κB/p65 to facilitate the binding of NF-κB/p65 to the S100A16 promoter, thereby activating the transcription and expression of S100A16. Mechanically, S100A16 responded to increasing Ca2+ and interacted with calmodulin (CaM) to regulate the activation of calcium/calmodulin-dependent protein kinase 2 (CAMKK2)/AMPK pathway. In conclusion, VDAC1 sustained the NF-κB p65 pathway activation to elicit increased S100A16 expression, contributing to myocardial damage and heart failure post-I/R via the CaM/CaMKK2/AMPK pathway. This study revealed a crucial role of the VDAC1-S100A16 axis in the process of myocardial I/R injury, providing novel molecular targets for the treatment of cardiac conditions associated with I/R injury.