Search Results (262)

The nutritional and quality characteristics of improved vegetable soybean genotypes were evaluated and compared with those of a grain-type soybean at the R6 (green maturity) and R8 (physiological maturity) stages. Significant variation (p < 0.05) was observed among genotypes for all measured traits. The overall quality parameters increased from the R6 (green maturity) stage to the R8 (physiological maturity) stage. Among the R6-stage genotypes, AVSB2001 recorded the highest contents of protein (15.30 ± 0.57 g/100 g), ash (2.31 ± 0.06 g/100 g), fat (8.05 ± 0.17 g/100 g), and calcium (140.78 ± 0.97 mg/100 g). The genotype Karune exhibited significantly higher levels of total sugars, non-reducing sugars, iron, and magnesium than the other entries. At the R8 stage, Swarna Vasundhara showed the highest protein content (39.23%), while AGS 447 recorded the highest values for fat, total sugars, in vitro protein digestibility, iron, copper, magnesium, and manganese. Notably, in vitro protein digestibility was lower across all genotypes at the R8 stage compared to the R6 stage. These findings suggest that selected vegetable soybean genotypes possess substantial nutritional value and can contribute meaningfully to meeting the recommended dietary allowance (RDA) across different age and occupational groups, underscoring this research’s potential public health impact. Based on stage-specific quality profiles, R6-stage genotypes may be better suited for fresh vegetables, whereas R8-stage genotypes can be utilized similarly to grain-type soybean for processing into products such as dhal, oil, flour, and other value-added foods. Full article

Aminoglycoside antibiotics are critical in clinical use for treating severe infections, but they can occasionally cause irreversible sensorineural hearing loss. To establish a rational pathway for otoprotectant discovery, we provide an integrated, three-tier methodology—comprising cell-model selection, transcriptomic analysis, and a gentamicin–Texas Red (GTTR) uptake assay—to guide the development of otoprotective strategies. We first utilized two murine auditory cell lines—UB/OC-2 and HEI-OC1. We focused on TMC1 and OCT2 and further explored the underlying mechanisms of ototoxicity. UB/OC-2 exhibited a higher sensitivity to gentamicin, which correlated with elevated OCT2 expression confirmed via RT-PCR and Western blot. Transcriptomic analysis revealed upregulation of PI3K-Akt, calcium, and GPCR-related stress pathways in gentamicin-treated HEI-OC1 cells. Protein-level analysis further confirmed that gentamicin suppressed phosphorylated Akt while upregulating ER stress markers (GRP78, CHOP) and apoptotic proteins (cleaved caspase 3, PARP). Co-treatment with PI3K inhibitors (LY294002, wortmannin) further suppressed Akt phosphorylation, supporting the role of PI3K-Akt signaling in auditory cells. To visualize drug entry, we used GTTR to evaluate its applicability as a fluorescence-based uptake assay in these cell lines, which were previously employed mainly in cochlear explants. Sodium thiosulfate (STS) and N-acetylcysteine (NAC) significantly decreased GTTR uptake, suggesting a protective effect against gentamicin-induced hair cell damage. In conclusion, our findings showed a complex ototoxic cascade involving OCT2- and TMC1-mediated drug uptake, calcium imbalance, ER stress, and disruption of PI3K-Akt survival signaling. We believe that UB/OC-2 cells serve as a practical in vitro model for mechanistic investigations and screening of otoprotective compounds. Additionally, GTTR may be a simple, effective method for evaluating protective interventions in auditory cell lines. Overall, this study provides molecular-level insights into aminoglycoside-induced ototoxicity and introduces a platform for protective strategies. Full article

Calcium (Ca²⁺) signaling is a fundamental regulatory mechanism controlling essential processes in the endothelium, vascular smooth muscle cells (VSMCs), and the extracellular matrix (ECM), including maintaining the endothelial barrier, modulation of vascular tone, and vascular remodeling. Cytosolic free Ca²⁺ concentration is tightly regulated by a balance between Ca²⁺ mobilization mechanisms, including Ca²⁺ release from the intracellular stores in the sarcoplasmic/endoplasmic reticulum and Ca²⁺ entry via voltage-dependent, transient-receptor potential, and store-operated Ca²⁺ channels, and Ca²⁺ elimination pathways including Ca²⁺ extrusion by the plasma membrane Ca²⁺-ATPase and Na⁺/Ca²⁺ exchanger and Ca²⁺ re-uptake by the sarco(endo)plasmic reticulum Ca²⁺-ATPase and the mitochondria. Some cell membranes/organelles are multifunctional and have both Ca²⁺ mobilization and Ca²⁺ removal pathways. Also, the individual Ca²⁺ handling pathways could be integrated to function in a regenerative, capacitative, cooperative, bidirectional, or reciprocal feed-forward or feed-back manner. Disruption of these pathways causes dysregulation of the Ca²⁺ signaling dynamics and leads to pathological cardiovascular conditions such as hypertension, coronary artery disease, atherosclerosis, and vascular calcification. In the endothelium, dysregulated Ca²⁺ signaling impairs nitric oxide production, reduces vasodilatory capacity, and increases vascular permeability. In VSMCs, Ca²⁺-dependent phosphorylation of the myosin light chain and Ca²⁺ sensitization by protein kinase-C (PKC) and Rho-kinase (ROCK) increase vascular tone and could lead to increased blood pressure and hypertension. Ca²⁺ activation of matrix metalloproteinases causes collagen/elastin imbalance and promotes vascular remodeling. Ca²⁺-dependent immune cell activation, leukocyte infiltration, and cholesterol accumulation by macrophages promote foam cell formation and atherosclerotic plaque progression. Chronic increases in VSMCs Ca²⁺ promote phenotypic switching to mesenchymal cells and osteogenic transformation and thereby accelerate vascular calcification and plaque instability. Emerging therapeutic strategies targeting these Ca²⁺-dependent mechanisms, including Ca²⁺ channel blockers and PKC and ROCK inhibitors, hold promise for restoring Ca²⁺ homeostasis and mitigating vascular disease progression. Full article

The L-type calcium channels (LTCCs) function as the main entry points that convert myocyte membrane depolarization into calcium transients, which drive every heartbeat. There is increasing evidence to show that maladaptive remodeling of these channels is the cause of heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). Recent experimental, translational, and clinical studies have improved our understanding of the roles LTCC expression, micro-domain trafficking, and post-translational control have in disrupting excitation–contraction coupling, provoking arrhythmias, and shaping phenotype specific hemodynamic compromise. We performed a systematic search of the PubMed and Google Scholar databases (2015–2025, English) and critically evaluated 17 eligible publications in an effort to organize the expanding body of work. This review combines existing data about LTCC density and T-tubule architecture with β-adrenergic and Ca²⁺/calmodulin-dependent protein kinase II (CaMKII) signaling and downstream sarcoplasmic reticulum crosstalk to explain how HFrEF presents with contractile insufficiency and how HFpEF shows diastolic calcium overload and stiffening. Additionally, we highlight the emerging therapeutic strategies aimed at restoring calcium homeostasis such as CaMKII inhibitors, ryanodine receptor type 2 (RyR2) stabilizers, and selective LTCC modulators without compromising systolic reserve. The review establishes LTCC dysregulation as a single mechanism that causes myocardial dysfunction while remaining specific to each phenotype, thus offering clinicians and researchers a complete reference for current concepts and future precision therapy approaches in heart failure. Full article

Rap1A and Rap1B are closely related small GTPases that regulate endothelial adhesion, vascular integrity, and signaling pathways via effector domain interactions, with downstream effectors controlling integrins and cadherins. Although both isoforms are essential for vascular development, recent studies using endothelial-specific knockout models have uncovered distinct, non-redundant functions. Rap1B is a key regulator of VEGFR2 signaling, promoting angiogenesis, nitric oxide production, and immune evasion in tumors while restraining proinflammatory signaling in atherosclerosis. In contrast, Rap1A unexpectedly functions as a modulator of endothelial calcium homeostasis by restricting Orai1-mediated store-operated calcium entry, thereby limiting inflammatory responses and vascular permeability. New insights into Rap1 regulation highlight the roles of context-specific guanine nucleotide exchange factors, such as RasGRP3, and non-degradative ubiquitination in effector selection. Emerging data suggest that isoform-specific interactions between the Rap1 hypervariable regions and plasma membrane lipids govern their localization to distinct nanodomains, potentially influencing downstream signaling specificity. Together, these findings redefine the roles of Rap1A and Rap1B in endothelial biology and highlight their relevance in diseases such as tumor angiogenesis, atherosclerosis, and inflammatory lung injury. We discuss the therapeutic implications of targeting Rap1 isoforms in vascular pathologies and cancer, emphasizing the need for isoform-specific strategies that preserve endothelial homeostasis. Full article

The endocannabinoid system (ECS) is known to regulate crucial bodily functions, including healthy muscle activity. However, its precise roles in normal skeletal muscle function and the development of muscle disorders remain unclear. Previously, we developed a tamoxifen-inducible, skeletal muscle-specific CB₁ receptor knockdown (skmCB1-KD) mouse model using the Cre/LoxP system. In this study, we aimed to clarify the mechanisms behind the observed reduction in muscle force generation in these mice. To investigate this, we analyzed calcium dynamics following electrical stimulation-induced muscle fatigue, assessed store-operated calcium entry (SOCE), and performed functional analysis of mitochondrial respiration. Our findings suggest that the reduced muscle performance observed in vivo likely arises from interconnected alterations in ATP production by mitochondria. Moreover, in skmCB1-KD mice, we detected a significant decrease in a component of the respiratory chain (complex IV) and a slowed dissipation of mitochondrial membrane potential upon the addition of an un-coupler (FCCP). Full article

Mechanogated (MG) ion channels play a crucial role in mechano-transduction and immune cell regulation, yet their impact on blood cancers, particularly acute lymphoblastic leukemia (ALL), remains poorly understood. This study investigates the pharmacological effects of GsMTx4, an MG channel inhibitor, in human ALL cells both in vitro and in vivo. Unexpectedly, we found that GsMTx4 remarkably increased basal calcium (Ca²⁺) levels in ALL cells through constitutive Ca²⁺ entry and enhanced store-operated Ca²⁺ influx upon thapsigargin stimulation. This increase in basal Ca²⁺ signaling promoted ALL cell viability and proliferation in vitro. Notably, chelating intracellular Ca²⁺ with BAPTA-AM reduces GsMTx4-mediated leukemia cell viability and proliferation. However, in vivo, GsMTx4 decreases cytosolic Ca²⁺ levels in Nalm-6 GFP⁺ cells isolated from mouse blood, effectively countering leukemia progression and significantly extending survival in NSG mice transplanted with leukemia cells (median survival: GsMTx4 vs. control, 37.5 days vs. 29 days, p = 0.0414). Our results highlight the different properties of GsMTx4 activity in in vitro and in vivo models. They also emphasize that Ca²⁺ signaling is a key vulnerability in leukemia, where its precise modulation dictates disease progression. Thus, targeting Ca²⁺ channels could offer a novel therapeutic strategy for leukemia by exploiting Ca²⁺ homeostasis. Full article

Ryanodine receptors (RyRs) are large intracellular Ca²⁺ release channels primarily found in muscle and nerve cells and also present at low levels in pancreatic islet endocrine cells. This review examines the role of RyRs in islet cell function, focusing on calcium signaling and hormone secretion, while addressing the ongoing debate regarding their significance due to their limited expression. We explore conflicting experimental results and their potential causes, synthesizing current knowledge on RyR isoforms in islet cells, particularly in beta and delta cells. The review discusses how RyR-mediated calcium-induced calcium release enhances, rather than drives, glucose-stimulated insulin secretion. We examine the phosphorylation-dependent regulation of beta-cell RyRs, the concept of “leaky ryanodine receptors”, and the roles of RyRs in endoplasmic reticulum stress, apoptosis, store-operated calcium entry, and beta-cell electrical activity. The relationship between RyR dysfunction and the development of impaired insulin secretion in diabetes is assessed, noting their limited role in human diabetes pathogenesis given the disease’s polygenic nature. We highlight the established role of RyR-mediated CICR in the mechanism of action of common type 2 diabetes treatments, such as glucagon-like peptide-1, which enhances insulin secretion. By integrating findings from electrophysiological, molecular, and clinical studies, this review provides a balanced perspective on RyRs in islet cell physiology and pathology, emphasizing their significance in both normal insulin secretion and current diabetes therapies. Full article

Background: Triple-negative breast cancer (TNBC) is an aggressive subtype lacking estrogen, progesterone, and HER2 receptors, and is associated with poor prognosis and limited targeted therapeutic options. TP53 mutations occur in the majority of TNBC cases, disrupting p53’s role in DNA repair and apoptosis. Beyond gene regulation, p53 also influences calcium signalling through store-operated calcium entry (SOCE), a critical pathway for cell survival and death. However, the impact of different TP53 mutation types on calcium signalling remains unclear. Methods: Calcium channel gene expression was analysed using publicly available TNBC datasets. Calcium channel expression and SOCE activity were assessed in TNBC cell lines with different TP53 mutations using quantitative PCR and calcium imaging (Fura-2AM). Cell proliferation was measured using acid phosphatase assays, while apoptosis was evaluated through caspase 3/7 activation using the Incucyte live-cell fluorescent imager. The p53 reactivator COTI-2 was tested for its ability to restore TP53 function and modulate calcium signalling. Results: Analysis revealed significant downregulation of CACNA1D in TP53-mutant TNBCs. TNBC cell lines harbouring frameshift and stop TP53 mutations exhibited reduced SOCE, lower CACNA1D expression, and resistance to thapsigargin-induced apoptosis compared to wild-type cells. In contrast, cells with the TP53 R273H missense mutation demonstrated similar calcium signalling and proliferation to TP53 wild-type cels. COTI-2 treatment restored CACNA1D expression and SOCE in frameshift and stop mutant cells, enhancing apoptotic sensitivity. Combined treatment with COTI-2 and thapsigargin resulted in a synergistic increase in apoptosis. Conclusions: This study identifies a novel link between TP53 mutation type and calcium signalling in TNBC. Reactivating mutant p53 with COTI-2 restores calcium-mediated apoptosis, supporting combination strategies targeting both TP53 dysfunction and calcium signalling. Full article

Multiple Sclerosis (MS) is a chronic autoimmune disorder characterized by demyelination and neuronal damage in the central nervous system. Dysregulation of calcium homeostasis, particularly through the Store-Operated Calcium Entry-Associated Regulatory Factor (SARAF), has been implicated in MS pathogenesis. This study investigated SARAF, STIM1, and Orai1 expression patterns and their relationship to calcium homeostasis in 45 Bahraini MS patients and 45 matched healthy controls using ELISA and real-time PCR analyses. MS patients showed significantly elevated serum SARAF levels in both early (192.26 ± 47.00 pg/mL) and late MS stages (341.47 ± 96.19 pg/mL) compared to controls (129.82 ± 30.82 pg/mL; p < 0.001. SARAF expressions were markedly increased in MS patients (3.829 ± 0.04422 vs. 1 ± 0; p < 0.0001), while STIM1 (0.4324 ± 0.01471) and ORAI1 (0.2963 ± 0.02156) expressions were significantly reduced compared to the controls (p < 0.0001). Intracellular calcium levels were notably elevated in both early and late MS stages. These findings suggest that the progressive elevation of SARAF, coupled with altered STIM1 and ORAI1 expression, may serve as potential biomarkers for MS progression and represent promising therapeutic targets. Full article

Hepatocellular carcinoma (HCC), a highly aggressive liver malignancy, is often associated with disrupted calcium homeostasis. Store-operated calcium entry (SOCE), involving components such as STIM1, Orai1, and SARAF, plays a critical role in calcium signaling and cancer progression. While STIM1 and Orai1 have been extensively studied, SARAF’s role as a negative regulator of SOCE in HCC remains poorly understood. This preliminary study investigated SARAF’s effects on calcium homeostasis, proliferation, and migration in HepG2 liver cancer cells, providing initial evidence of its tumor-suppressive role. SARAF expression was modulated using siRNA knockdown and overexpression plasmids, with validation by qRT-PCR. Functional assays demonstrated that SARAF silencing increased proliferation by 50% and migration by 40% (p < 0.05), while SARAF overexpression reduced proliferation by 50% and migration by 45% (p < 0.01), highlighting its tumor-suppressive role. Intracellular calcium levels, elevated in HepG2 cells, were partially restored by SARAF overexpression, though SARAF silencing did not further disrupt calcium regulation. These findings suggest that SARAF negatively regulates proliferation and migration in HCC, potentially through its role in maintaining calcium homeostasis. SARAF represents a promising therapeutic target in HCC. Future studies should explore the downstream molecular mechanisms governing SARAF’s effects, investigate its role in other cancers, and assess its clinical potential for liver cancer therapy. Full article

High-risk neuroblastoma (HRNB) is an extracranial solid pediatric cancer. Despite the plethora of treatments available for HRNB, up to 65% of patients are refractory or exhibit an initial response to treatment that transitions to therapy-resistant relapse, which is invariably fatal. A key feature that promotes HRNB progression is aberrant calcium (Ca²⁺) signaling. Ca²⁺ signaling is regulated by several druggable channel proteins, offering tremendous therapeutic potential. Unfortunately, many of the Ca²⁺ channels in HRNB also perform fundamental functions in normal healthy cells, hence targeting them increases the potential for adverse effects. To overcome this challenge, we sought to identify novel Ca²⁺ signaling pathways that are observed in HRNB but not normal non-cancerous cells with the hypothesis that these novel pathways may serve as potential therapeutic targets. One Ca²⁺ signaling pathway that is deregulated in HRNB is store-operated Ca²⁺ entry (SOCE). SOCE relays the release of Ca²⁺ from the endoplasmic reticulum (ER) and Ca²⁺ influx via the plasma membrane and promotes cancer drug resistance by regulating transcriptional programming and the induction of mitochondrial Ca²⁺ (mtCa²⁺)-dependent signaling. mtCa²⁺ signaling is critical for cellular metabolism, reactive oxygen production, cell cycle, and proliferation and has a key role in the regulation of cell death. Therefore, a dynamic interplay between ER, SOCE, and mitochondria tightly regulates cell survival and apoptosis. From a library of synthesized novel molecules, we identified two structurally related compounds that uniquely disrupt the dynamic interplay between SOCE, ER, and mitochondrial signaling pathways and induce cell death in HRNB. Our results revealed that compounds 248 and 249 activate distinct aberrant Ca²⁺ signals that are unique to relapsed HRNB and could be exploited to induce mtCa⁺ overload, a novel calcium influx current, and subsequent cell death. These findings establish a potential new pathway of calcium-mediated cell death; targeting this pathway could be critical for the treatment of refractory and relapsed HRNB. Full article

In order to address the issue of wind leakage leading to spontaneous coal combustion in goafs during gob-side entry mining, a KH570 silane coupling agent (SCA)-modified vinyl acetate–ethylene (VAE)/cement-based flexible spraying sealing material was developed. The mechanical properties and wind leakage sealing performance of the material were evaluated using specialized testing equipment. Furthermore, molecular dynamics simulations and microstructural characterization techniques were utilized to assess and model the interface compatibility of the material. The experimental results demonstrate that KH570 significantly enhanced the material’s mechanical properties. Following modification, the material exhibited increases in the maximum tensile strength, compressive strength, and flexural strength by 53%, 38%, and 29%, respectively. KH570 not only promotes the formation of additional calcium silicate hydrate (C-S-H) gel through cement hydration, but also establishes Si-O-Si chemical bonds with cement hydration products and hydrogen bonds with the VAE emulsion. This functions as a “molecular bridge”, significantly enhancing the interface performance of the composite. The interaction between the organic and inorganic phases contributes to the formation of an interpenetrating network structure, imparting excellent compressive, flexural, and tensile deformation resistance to the material. The wind leakage of the spray-modified material was reduced by 2.7 times compared to the unmodified material, significantly improving its sealing performance under mining-induced pressure conditions. This enhancement effectively minimizes spontaneous combustion in mined-out coal areas caused by wind leakage, thereby ensuring safer mining operations. Full article

Lung cancer remains the most common malignancy independent of sex. Here, we focused on unraveling the molecular mechanisms of CaS nanoclusters inducing cytotoxicity by investigating DNA damage, the cell cycle, oxidative stress, and cellular repair mechanisms in non-small-cell lung carcinoma (NSCLC) cells compared to healthy lung fibroblasts. Our previous studies have demonstrated the therapeutic potential of calcium sulfide (CaS) nanostructures in skin and breast cancer models, leading to a significant reduction in cancer cell proliferation. However, how CaS nanoclusters enhance their therapeutic effects on cancer cells while minimizing damage to healthy cells remains unknown. Our results show that CaS nanoclusters, once dissociated into ${Ca}^{2+}$ and $H_{2}S$ in an acidic microenvironment, selectively allow extracellular calcium to enter, leading to an increase in free calcium entry, triggering oxidative stress and limiting DNA repair mechanisms in NSCLC. Furthermore, CaS nanoclusters selectively arrest NSCLC cells in the G0-G1 and S phases of the cell cycle without affecting healthy cells’ cycles. Here, we also show that the selective effects of CaS nanoclusters on lung adenocarcinoma are less likely to be regulated by intrinsic apoptotic or mitochondrial pathways. They are, rather, caused by an increase in Ca²⁺ and ROS, causing double-stranded DNA breakages. This selectivity for malignant cells is pH-dependent because it occurs in the acidic microenvironment characteristic of these cells. Overall, this is the first piece of evidence that CaS disrupts genomic stability, prevents the replication of damaged cells, and ultimately influences cell fate decisions such as cell cycle arrest or cell death including mitotic catastrophe and necroptotic simultaneous events. Full article

α-Latrotoxin (αLTX) causes exhaustive release of neurotransmitters from nerve terminals in the absence of extracellular Ca²⁺ (Ca²⁺_e). To investigate the mechanisms underlying this effect, we loaded mouse neuromuscular junctions with BAPTA-AM. This membrane-permeable Ca²⁺-chelator demonstrates that Ca²⁺_e-independent effects of αLTX require an increase in cytosolic Ca²⁺ (Ca²⁺_cyt). We also show that thapsigargin, which depletes Ca²⁺ stores, induces neurotransmitter release, but inhibits the effect of αLTX. We then studied αLTX’s effects on Ca²⁺_cyt using neuroblastoma cells expressing signaling-capable or signaling-incapable variants of latrophilin-1, a G protein-coupled receptor of αLTX. Our results demonstrate that αLTX acts as a cation ionophore and a latrophilin agonist. In model cells at 0 Ca²⁺_e, αLTX forms membrane pores and allows the influx of Na⁺; this reverses the Na⁺-Ca²⁺ exchanger, leading to the release of stored Ca²⁺ and inhibition of its extrusion. Concurrently, αLTX stimulates latrophilin signaling, which depletes a Ca²⁺ store and induces transient opening of Ca²⁺ channels in the plasmalemma that are sensitive to inhibitors of store-operated Ca²⁺ entry. These results indicate that Ca²⁺ release from intracellular stores and that Ca²⁺ influx through latrophilin-activated store-operated Ca²⁺ channels contributes to αLTX actions and may be involved in physiological control of neurotransmitter release at nerve terminals. Full article