Search Results (69)

Background/Objectives: Thrombocytopenia in chronic lymphocytic leukemia (CLL) is a heterogeneous and multifactorial complication that often reflects the combined effects of immune dysregulation, impaired megakaryopoiesis, bone marrow microenvironmental disruption, and disease-related factors. In patients with high-risk molecular features, particularly TP53 abnormalities, management becomes increasingly challenging and frequently refractory to conventional therapies. Methods: We report a 57-year-old male with long-standing CLL characterized by a highly aggressive and treatment-refractory course. The patient developed persistent severe thrombocytopenia despite multiple lines of therapy, including corticosteroids, intravenous immunoglobulin, rituximab, splenectomy, and thrombopoietin receptor agonists. Subsequent treatments with ibrutinib and a venetoclax-based regimen failed to improve platelet counts and were discontinued due to worsening cytopenia. Bone marrow evaluation, molecular/cytogenetic analyses, and subsequent treatment responses were thoroughly evaluated. Results: Bone marrow evaluation revealed hypercellularity with significant CLL infiltration, dysplastic megakaryopoiesis, and reticulin fibrosis, indicating impaired platelet production in addition to immune-mediated destruction. Molecular and cytogenetic analyses demonstrated high-risk disease with deletion of 17p and dual TP53 mutations (p.His179Tyr and p.Arg282Trp), consistent with biallelic TP53 disruption. Romiplostim monotherapy did not result in a meaningful hematologic response. However, following the addition of idelalisib, a rapid and sustained increase in platelet counts was observed, allowing tapering of romiplostim and stabilization of hematologic parameters. Conclusions: This case highlights the complex and dynamic pathophysiology of thrombocytopenia in CLL, where immune-mediated destruction and defective thrombopoiesis coexist within a profoundly altered marrow microenvironment. TP53 disruption appears to play a central role not only in driving treatment resistance but also in promoting immune dysregulation and disease aggressiveness. Although a delayed therapeutic effect of romiplostim cannot be entirely excluded, the distinct temporal association following idelalisib initiation suggests a potential collaborative interaction or disease-directed clearance that may facilitate platelet recovery in this setting. Refractory thrombocytopenia in CLL should be approached as a manifestation of complex disease biology rather than an isolated complication. This single observation indicates that in TP53 aberrant cases with multi-mechanism thrombocytopenia, disease-directed targeted therapy may contribute significantly to platelet recovery. Full article

The human corneal endothelium (HCE) is critical for maintaining corneal transparency. Dysfunctions due to cell loss are linked to altered intracellular calcium ([Ca²⁺]_i) homeostasis. Transient receptor potential channels (TRPs) are key regulators of [Ca²⁺]_i, and both L-ascorbic acid (Asc) and cannabinoid receptor (CB) agonists have been implicated in modulating TRP activity. This study investigated the effects of 1 mM Asc and the CB agonist WIN 55,212-2 (WIN) (10 µM) on [Ca²⁺]_i regulation in human corneal endothelial cells (HCECs). HCEC-12 was used as the established HCE cell model. [Ca²⁺]_i dynamics were assessed by fura-2/AM fluorescence imaging, and membrane currents were analyzed using planar patch-clamp recordings. Adding 1 mM Asc increased [Ca²⁺]_i, which was partially suppressed by the TRPV1 blocker AMG-9810 (AMG) (20 µM) and the TRPV4 blocker GSK2193874 (GSK219) (10 µM). Furthermore, 1 mM Asc increased whole-cell currents. WIN also induced [Ca²⁺]_i transients that were partially attenuated by AMG, the TRPM8 blocker AMTB (20 µM), GSK219, and the CB1 inverse agonist AM251 (10 µM). In addition, combined treatment with Asc and WIN enhanced [Ca²⁺]_i elevations compared with either treatment alone. These findings provide the first evidence for a functional interaction between TRP channel activity and CB signaling in HCECs. The inhibitory effect of AM251 suggests a predominant contribution of CB1 receptors. Given the central role of Ca²⁺ homeostasis in corneal endothelial function and disease, these results may contribute to a better understanding of endothelial pathophysiology and support further investigation of TRPs and cannabinoid signaling as potential targets in corneal disorders. Full article

Background: There is currently increasing interest in atypical opioid compounds capable of expanding their clinical applications beyond pain management, including the treatment of psychiatric disorders and substance abuse. In this context, the cyclotetrapeptide c[Trp-Phe-D-Pro-Phe] (CJ-15,208, 1) and its derivatives represent an unusual class of opioid peptides. This compound was found to be a mixed KOR/MOR antagonist in vitro, but it acted as an agonist in vivo. For its diverse analogues, it appeared that receptors’ affinity, selectivity, and agonist/antagonist activity greatly varied upon modifications to backbone geometry and the 3D display of pharmacophores. Methods: We utilized NMR, molecular dynamics, and molecular docking to analyze 3D structures and pharmacodynamic properties of selected representative cyclopeptide analogues of 1. Results: The simulations support that, despite its contradictory functional activity in vitro and in vivo, 1 can bind to the active conformation of receptors in an agonist-like fashion. In general, Trp appeared to be the fundamental pharmacophore in the ligand–receptor complexes. In particular, agonists showed a direct interaction between the indole ring and the carboxylate of the conserved Asp(3:32). Conclusions: These studies support a distinctive pharmacodynamic model for this class of compounds, potentially useful for the design of opioid compounds with novel binding/activity profiles and improved therapeutic effects. Full article

Familial partial lipodystrophy type 3 (FPLD3) is a rare autosomal dominant disorder caused by mutations in peroxisome proliferator-activated receptor gamma(PPARG), which encodes the key adipogenic transcription factor peroxisome proliferator-activated receptor gamma(PPARγ). Clinical diagnosis is challenging due to phenotypic overlap with common metabolic syndromes. We identified a novel PPARG variant in a Chinese family and performed comprehensive functional characterization to elucidate its pathogenic mechanism. The proband, a 15-year-old boy presenting with atypical fat distribution, severe insulin resistance, hypertriglyceridemia, and pancreatitis, underwent clinical evaluation and whole-exome sequencing. The identified variant was confirmed by Sanger sequencing. Its functional impact was assessed through in silico modeling, luciferase reporter assays, protein stability analysis (cycloheximide chase), and evaluation of mitochondrial function (JC-1 staining) and adipocyte gene expression in cellular models. A heterozygous PPARG c.634C>T (p.Arg212Trp, R212W) variant was identified and segregated with the phenotype. Functional studies revealed that the R212W mutant exhibits a partial loss of transcriptional activity (~40% of wild-type) while retaining ligand sensitivity. Crucially, we demonstrated that the mutant protein has significantly reduced stability due to accelerated degradation. In adipocyte models, R212W expression led to impaired mitochondrial membrane potential, depleted cellular ATP levels, and downregulated expression of key metabolic genes (glucose transporter 4[GLUT4], adiponectin[ADIPOQ], fatty acid binding protein 4[FABP4], lipoprotein lipase[LPL], perilipin 1[PLIN1]). These functional deficits were partially rescued by treatment with the PPARγ agonist rosiglitazone. We report a novel pathogenic PPARG R212W variant associated with FPLD3. Our data extend beyond a simple loss-of-function model by establishing a multi-faceted pathogenic mechanism involving protein destabilization, mitochondrial dysfunction, and cellular bioenergetic failure. The partial rescue by rosiglitazone suggests a potential therapeutic avenue. This study underscores the importance of integrating clinical phenotyping with deep functional analysis to diagnose and understand rare monogenic lipodystrophies. Full article

Butterfly wing color pattern formation is a process of two-dimensional morphogenesis involving long-range lateral signaling in pupal wing tissues. We hypothesized that TRP (transient receptor potential) channels, which are multimodal sensors for various stimuli, are involved in this developmental process. Using the blue pansy butterfly Junonia orithya, we injected the TRPA1 antagonists, AM0902 and AP-18, and an agonist, JT010, into pupae and observed that the eyespot core disk area in adult wings increased and decreased in response to AM0902 and JT010, respectively, although AP-18 did not induce any change. Furthermore, the eyespot outer black ring area increased in response to AM0902, and the orange ring area increased in response to JT010. We detected TRPA1 mRNA via RT-PCR in the pupal wing tissues of this species. An antibody against the J. orithya TRPA1 extracellular site induced unique aberrant color patterns with wing vein defects. These results suggest that TRPA1 is expressed in pupal wing tissue and may integrate signaling information to determine eyespot size and structure in butterfly wings. TRPA1 likely suppresses the black core disk and the outer black ring and enhances the nonblack orange ring in eyespots during development. Full article

Dental pain often arises from the compromised integrity of the tooth pulp due to dental injury or caries. The dentin–pulp complex has long been considered to be central to the unique biology of dental pain. Most trigeminal ganglion afferents projecting into tooth pulp are myelinated neurons, which lose their myelination at the site of peripheral dentin innervation. The pulpal afferents likely combine multiple internal and external stimuli to mediate nociception and maintain pulp homeostasis. Transient receptor potential (TRP) ion channels in neurons and odontoblasts, along with mechanosensitive ion channels such as Piezo, form a key molecular hub for pulpal nociception by sensing thermal, chemical, and hydrodynamic stimuli. Among these, TRP vanilloid 1 (TRPV1) mediates nociception and the release of calcitonin-gene-related peptides (CGRPs), while TRP canonical 5 (TRPC5) mediates cold pain. TRP melastatin 8 (TRPM8) mediates the transduction of hyperosmotic stimuli. Pulpitis elevates endogenous TRPV1 and TRPA1 agonists, while inflammatory mediators sensitize TRP channels, amplifying pain. CGRP recruits immune cells and promotes bacterial clearance and reparative dentinogenesis, yet the roles of TRP channels in these processes remain unclear. Future studies should use advanced multi-omics and in vivo or organotypic models in animal and human teeth to define TRP channel contributions to pain, immune responses, and regeneration. Understanding neuronal and non-neuronal TRP channel interactions and their integration with other ion channels may enable novel analgesic and regenerative strategies in dentistry. Full article

Major depressive disorder is increasingly recognized as a metabolic–immune disorder in which chronic inflammation diverts tryptophan (Trp) metabolism toward the kynurenine pathway (KP), reducing serotonin synthesis and producing neurotoxic metabolites such as quinolinic acid (QA). Elevated kynurenine (KYN)/Trp ratios and an altered QA/kynurenic acid (KYNA) balance have been consistently reported in depressed individuals, implicating the KP as a key therapeutic target. Exercise provides a unique, translationally relevant intervention: unlike pharmacological agents acting directly on neurotransmission, contracting skeletal muscle acts as a “kynurenine sink” by inducing kynurenine aminotransferases that convert circulating KYN into neuroprotective KYNA, thereby reducing brain KYN uptake and mitigating excitotoxicity. Clinical studies and meta-analyses confirm that aerobic, resistance, and high-intensity training produce antidepressant effects comparable to pharmacotherapy, while also improving cognition, fatigue tolerance, and cardiometabolic function. Beyond KP remodeling, exercise-induced myokines (irisin, IL-6, BDNF, apelin, FGF21) and adipokines (adiponectin, leptin modulators) coordinate systemic anti-inflammatory and neurotrophic adaptations that enhance resilience and brain plasticity. Furthermore, pharmacological “exercise mimetics” and metabolic modulators, such as PPAR agonists, AMPK activators, NAD⁺ boosters, meldonium, trimetazidine, and adiponectin receptor agonists, may be promising adjuncts for patients with low exercise capacity or metabolic comorbidities. This review provides a novel concept, positioning exercise as a systemic antidepressant that breaks the kynurenine lock of depression. Through proper interpretation of skeletal muscle as an endocrine organ of resilience, we integrate molecular, clinical, and translational findings to show how exercise remodels Trp–KYN metabolism and inflammatory signaling and how pharmacological mimetics may extend these benefits. This perspective consolidates scattered mechanistic and clinical data and outlines a forward-looking therapeutic framework that links exercise and lifestyle, metabolism, and drug discovery. We highlight that re-consideration of our understanding of depression, as a whole-body disorder, should provide new opportunities for precision interventions. Full article

The cannabinoid receptor type 2 (CB₂) is increasingly recognized as a crucial regulator of neuroimmune balance in the brain. In addition to its well-established role in immunity, the CB₂ receptor has been identified in specific populations of neurons and glial cells throughout various brain regions, and its expression is dynamically increased during inflammatory and neuropathological conditions, positioning it as a potential non-psychoactive target for modifying neurological diseases. The expression of the CB₂ gene (CNR2) is finely tuned by epigenetic processes, including promoter CpG methylation, histone modifications, and non-coding RNAs, which regulate receptor availability and signaling preferences in response to stress, inflammation, and environmental factors. CB₂ signaling interacts with TRP channels (such as TRPV1), nuclear receptors (PPARγ), and orphan G Protein-Coupled Receptors (GPCRs, including GPR55 and GPR18) within the endocannabinoidome (eCBome), influencing microglial characteristics, cytokine production, and synaptic activity. We review how these interconnected mechanisms affect neurodegenerative and neuropsychiatric disorders, underscore the species- and cell-type-specificities that pose challenges for translation, and explore emerging strategies, including selective agonists, positive allosteric modulators, and biased ligands, that leverage the signaling adaptability of the CB₂ receptor while reducing central effects mediated by the CB₁ receptor. This focus on the neuro-centric perspective repositions the CB₂ receptor as an epigenetically informed, context-dependent hub within the eCBome, making it a promising candidate for precision therapies in conditions featuring neuroinflammation. Full article

Swallowing is mediated by the central nervous system, including cortical and subcortical structures, the cerebellum, and the brainstem. The brainstem contains the swallowing centre that is crucial for initiating and coordinating swallowing. Consequently, brainstem damage due to stroke often leads to severe and persistent dysphagia. The aim of the present narrative review is to provide an overview of dysphagia following brainstem stroke and its management. It summarizes the physiology and pathophysiology of dysphagia following brainstem stroke and the available therapeutic options, and evaluate their effectiveness for dysphagia following brainstem stroke, which would promote the development of therapeutic protocols. Neuromodulatory techniques, including pharyngeal electrical stimulation (PES), repetitive transcranial magnetic stimulation (rTMS), and transcranial direct current stimulation (tDCS), modulate the excitability of corticobulbar circuits. These techniques promote neuroplasticity through peripheral or cortical electrical or electromagnetic inputs. Skill-based swallowing training emphasizes cortical involvement in enhancing swallowing skill, offering a targeted approach to behavioural rehabilitation. Finally, transient receptor potential (TRP) agonists increase sensory inputs to the swallowing system by stimulating the sensory receptors in the oropharynx, potentially activating the swallowing network. While these options have shown promise in dysphagia rehabilitation following stroke, most the available data comes from patients with mixed stroke lesions, with limited data focused specifically on brainstem lesions. Therefore, the evidence for their efficacy in patients with brainstem stroke remains underexplored. Therefore, treatment decisions should rely on the understanding of swallowing physiology, neuroplasticity, and clinical evidence from related stroke populations. Full article

Background: TRPC6 is recognized as a therapeutically relevant cation channel, whose activation is governed by specific ligand–pocket interactions. Methods: An integrated in silico workflow was employed, comprising structure-based docking, 100-nanosecond molecular dynamics (MD) simulations, and MM-GBSA calculations. Benzoic-acid–based compounds were designed and prioritized for binding to the TRPC6 pocket, using a known literature agonist as a reference for benchmarking. Results: Within the compound series, BT11 was found to exhibit a representative interaction profile, characterized by a key hydrogen bond with Trp680 (~64% occupancy), persistent salt-bridge interactions with Lys676 and Lys698, and π–π stacking with Phe675 and Phe679. A favorable docking score (−11.45 kcal/mol) was obtained for BT11, along with a lower complex RMSD during MD simulations (0.6–4.8 Å), compared with the reference compound (0.8–7.2 Å). A reduction in solvent-accessible surface area (SASA) after ~60 ns was also observed, suggesting decreased water penetration. The most favorable binding energy was predicted for BT11 by MM-GBSA (−67.72 kcal/mol), while SOH95 also ranked highly and slightly outperformed the reference. Conclusions: These convergent computational analyses support the identification of benzoic-acid–derived chemotypes as potential TRPC6 ligands. Testable hypotheses are proposed, along with structure–activity relationship (SAR) guidelines, to inform experimental validation and guide the design of next-generation analogs. Full article

The development of orally bioavailable non-peptidomimetic glucagon-like peptide-1 receptor agonists (GLP-1RAs) offers a promising therapeutic avenue for the treatment of type 2 diabetes mellitus (T2DM) and obesity. An extensive in silico approach combining structure-based drug design and ligand-based strategies together with pharmacokinetic properties and drug-likeness predictions is implemented to identify novel non-peptidic GLP-1RAs from the COCONUT and Marine Natural Products (CMNPD) libraries. More than 700,000 compounds were screened by shape-based similarity filtering in combination with precision docking against the orthosteric site of the GLP-1 receptor (PDB ID: 6X1A). The docked candidates were further assessed with the molecular mechanics MM-GBSA tool to check the binding affinities; the final list of candidates was validated by running a 500 ns long MD simulation. Twenty final hits were identified, ten from each database. The hits contained compounds with reported antidiabetic effects but with no evidence of GLP-1 agonist activity, including hits 1, 6, 7, and 10. These findings proposed a novel mechanism for these hits through GLP-1 activity and positioned the other hits as potential promising scaffolds. Among the studied compounds—especially hits 1, 5, and 9—possessed strong and stable interactions with critical amino acid residues such as TRP-203, PHE-381, and GLN-221 at the active site of the 6X1A-substrate along with favorable pharmacokinetic profiles. Moreover, the RMSF and RMSD plots further suggested the possibility of stable interactions. Specifically, hit 9 possessed the best docking score with a ΔG_bind value of −102.78 kcal/mol, surpassing even the control compound in binding affinity. The ADMET profiling also showed desirable drug-likeness and pharmacokinetic characteristics for hit 9. The pipeline of computational integration underscores the potential of non-peptidic alternatives in natural product libraries to pursue GLP-1-mediated metabolic therapy into advanced preclinical validation. Full article

Comparative studies using lysophosphatidic acid (LPA) and the synthetic agonist, oleoyl-methoxy glycerophosphothionate (OMPT), in cells expressing the LPA₃ receptor revealed differences in the action of these agents. The possibility that more than one recognition cavity might exist for these ligands in the LPA₃ receptor was considered. We performed agonist docking studies exploring the whole protein to obtain tridimensional details of the ligand–receptor interaction. Functional in cellulo experiments using mutants were also executed. Our work includes blind docking using the unrefined and refined proteins subjected to hot spot predictions. Distinct ligand protonation (charge −1 and −2) states were evaluated. One LPA recognition cavity is located near the lower surface of the receptor close to the cytoplasm (Lower Cavity). OMPT displayed an affinity for an additional identification cavity detected in the transmembrane and extracellular regions (Upper Cavity). Docking targeted to Trp102 favored binding of both ligands in the transmembrane domain near the extracellular areas (Upper Cavity), but the associating amino acids were not identical due to close sub-cavities. A receptor model was generated using AlphaFold3, which properly identified the transmembrane regions of the sequence and co-modeled the lipid environment accordingly. These two models independently generated (with and without the membrane) and adopted essentially the same conformation, validating the data obtained. A DeepSite analysis of the model predicted two main binding pockets, providing additional confidence in the predicted ligand-binding regions and support for the relevance of the docking-based interaction models. In addition, mutagenesis was performed of the amino acids of the two detected cavities. In the in cellulo studies, LPA action was much less affected by the distinct mutations than that of OMPT (which was almost abolished). Therefore, docking and functional data indicate the presence of distinct agonist binding cavities in the LPA₃ receptor. Full article

Caigua (Cyclanthera pedata (L.) Schrad.) is a traditional herbal remedy traditionally used in Latin America for its health benefits and to treat metabolic disorders, including diabetes. Despite interest in its herbal use, the phytochemical properties of caigua’s secondary metabolites are poorly known. This study aimed to isolate the main flavone glycosides from the leaves of caigua landrace cultivated in the Camonica Valley (Italy) using flash chromatography and evaluate their potential activity toward peroxisome proliferator-activated receptors (PPARs) and transient receptor potential (TRP) ion channels through luciferase and intracellular calcium assays. We found that the caigua species-specific flavone glycoside, chrysin-6-C-fucopyranoside, showed potent and selective activity toward PPARγ, with no effects on other PPAR subtypes or TRP channels. These findings indicate that the caigua plant could offer a safer alternative to conventional PPARγ agonists, whose use as antidiabetic drugs is limited by severe side effects that currently restrict the clinical use of conventional PPAR agonists. Full article

The central nervous system (CNS) relies on complex and dynamic interactions between neurons and glial cells. Among glial cells, astrocytes regulate the chemical environment surrounding neurons and supply essential nutrients for brain metabolism whereas microglia, the resident macrophages of the CNS, play critical roles in homeostasis, defense, and responses to injury. Both microglia and astrocytes contribute to the regulation of excitotoxicity and inflammation mediated by the metabolism of tryptophan (Trp) via the kynurenine pathway. Trp metabolism generates several bioactive metabolites, including quinolinic acid (QUIN) and kynurenic acid (KYNA), which have opposing effects. QUIN, produced by activated microglia, acts as an agonist for NMDA receptors; excessive stimulation of these receptors can lead to excitotoxicity and neuronal death. Conversely, KYNA, primarily produced by astrocytes via kynurenine 2,3-aminotransferases (KAT), acts as an NMDA receptor antagonist, conferring neuroprotection by mitigating excitotoxicity. Dysregulation of the Trp metabolism is implicated in many neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease, multiple sclerosis and amyotrophic lateral sclerosis, as well as in various neuropsychiatric disorders. This review examines the cellular and molecular mechanisms underlying Trp metabolism in glial cells, highlighting the unique contributions of each glial phenotype, the implications for CNS pathologies, and the potential biomarkers and therapeutic targets for restoring homeostasis and preventing disease progression. Full article

Due to its central role in pain, inflammation, and related disorders, the Transient Receptor Potential (TPR) Vanilloid Type-1 (TRPV1) ion channel represents an attractive target for the development of novel antinociceptive and anti-inflammatory agents. Capsaicin, the natural component of chili peppers, is one of the most investigated agonists of this receptor. Several modifications of its structure have been attempted, aiming at finding TRPV1 agonists with improved characteristics, but, to date, no capsaicin-derived agents have reached the market. Based on our previous knowledge of the design and synthesis of TRPV1 agonists, in this paper we propose two small series of indole-2-carboxamides as novel and selective agonists for this ion channel. The newly developed compounds have been structurally characterized and tested in vitro for their ability to modulate TRPV1, in terms of efficacy, potency (EC₅₀), and desensitization (IC₅₀) properties. For the most promising derivatives, selectivity over the TRP ankyrin-1 (TRPA1) channel has been reported. From our study, compound 6g arose as a promising candidate for further evaluation, also in correlation with its in silico-predicted drug-like properties. Full article