Search Results (1,690)

Heat waves have intensified since the 1960s, leaving older adults uniquely susceptible to heat-related illnesses, including hyperthermia and fluid-electrolyte imbalances. While clinicians recognize that certain medications increase heat vulnerability, the specific interplay between drug use and patient characteristics remains unclear. This scoping review, following the Joanna Briggs Institute framework for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines, investigated the risk of heat-related illness associated with medication use in older adults to identify research gaps. Investigators queried four databases for English-language primary literature (2000–2025) based on predefined Population, Concept, and Context criteria. Additionally, a grey literature search mapped existing United States (U.S.) mitigation strategies. Two reviewers independently screened studies via Covidence, and one extracted data. Results included 61 primary studies and 41 grey literature sources. While epidemiological data confirm higher heat-related morbidity and mortality in older populations, few experimental studies evaluate medication’s specific role. Despite many public health efforts, specific, evidence-based guidance on managing drug-heat interactions is limited. Diuretics, angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), anticholinergics, and antipsychotics were the medication classes most frequently associated with heat-related illness. This review underscores a critical need for research into the confluence of age, multimorbidity, and polypharmacy to inform future clinical mitigation and protect vulnerable populations. Full article

Salivary gland infection by SARS-CoV-2 requires viral entry via routes and mechanisms that remain unresolved. This study examined the expression of the angiotensin-converting enzyme 2 (ACE2) receptor in salivary tissues and basal cell-derived human salivary progenitor cells (hS/PCs), an unstudied potential entry point for SARS-CoV-2. Multiple detection modalities, including immunocytochemistry, Western blotting, flow cytometry and RT-PCR, demonstrated a consistent lack of ACE2 protein and transcript in both tissue specimens and primary salivary epithelial cells. Antigen retrieval at pH 9 was determined to be optimal for immunodetection protocols, yet ACE2 remained undetectable. Small intestine tissue served as a positive control, confirming the validity of the methods and reagents we used. Considering there can be other receptors for SARS-CoV-2, flow cytometric analyses demonstrated that recombinant SARS-CoV-2 spike protein failed to bind to salivary epithelial cells, in contrast to HEK293 cells engineered to overexpress ACE2, which showed robust spike binding. Additional studies showed that patient-derived salivary cells, negative for ACE2, are not infected by the SARS-CoV-2 pseudovirus, while ACE2-positive cells are readily infected. These findings strongly support our conclusion that salivary cells do not serve as major targets for SARS-CoV-2 infection via ACE2, spike protein, or an alternate receptor. Thus, salivary cells are unlikely major targets for SARS-CoV-2 infection, either through direct exposure to viral particles in ductal fluids or via access to basal cells across the basement membrane. Full article

Background/Objectives: While the functions of angiotensin-converting enzyme (ACE) 1 and 2 are well established in peripheral tissues, the role of the spinal ACE1 and ACE2 pathways in the development of neuropathic pain remains unclear. This study examined the role of the spinal ACE1 and ACE2 pathways in trigeminal neuropathic pain produced by inferior alveolar nerve (IAN) injury. Methods: The experiments were conducted using male Sprague-Dawley rats (6–8 weeks old, weighing 220–250 g). The left mandibular second molar was extracted, and a dental mini-implant was placed to induce IAN injury. IAN injury produced robust and long-lasting mechanical allodynia and markedly increased angiotensinogen (AGT) expression within the ipsilateral trigeminal subnucleus caudalis (iTSC). Results: Neuropathic mechanical allodynia was inhibited by intracisternally administered losartan (an angiotensin II type-1 receptor antagonist), but not by an angiotensin II type-2 receptor antagonist. Intracisternal treatment with captopril (an ACE1 inhibitor) and diminazene aceturate (an ACE2 activator) produced significant anti-allodynic effects. Intracisternally injected angiotensin-(1-7) reduced neuropathic mechanical allodynia, and this anti-allodynic effect was blocked by pretreatment with A779, a Mas receptor inhibitor. In naïve rats, the intracisternal administration of DX600 (an ACE2 inhibitor) resulted in mechanical allodynia, which was inhibited by intracisternal pretreatment with losartan. IAN injury led to upregulated ACE1 expression and downregulated ACE2 expression in the iTSC. Conclusions: Our findings indicate that IAN injury induces a polarized shift in the ACEs within the iTSC, characterized by increased ACE1 and decreased ACE2 expression. Their modulation may therefore offer a promising strategy for developing effective treatments for chronic pain. Full article

Background: Glucagon-like peptide-1 receptor agonist (GLP-1 RA) use has increased exponentially as studies show significant benefits in cardiovascular and renal diseases and obesity. Accessibility to the public also increased after compounding pharmacies began direct-to-consumer distribution. Gastrointestinal side effects are common; however, hypersensitivity reactions are rare. Case Presentation: A 50-year-old female with a history of obesity, hypertension, and lisinopril-induced angioedema presented to the Emergency Department with swelling of the lips, tongue, and throat developing four hours after her first injection of compounded semaglutide for weight loss. She was treated with epinephrine, corticosteroids, and antihistamines, but due to progressive airway edema, she required intubation and mechanical ventilation for four days. After extubation, she reported accidentally injecting a ten-fold higher dose (2 mg) of semaglutide than was appropriate for the first dose. The hospitalization was complicated by hypoglycemia requiring dextrose infusion, but was otherwise unremarkable, and she was discharged home on day 7. Based on the temporal onset after semaglutide injection, this presentation was most consistent with GLP-1 RA-induced angioedema. While she also had a history of lisinopril-induced angioedema five years earlier, and had been taking valsartan for hypertension, the remoteness of the lisinopril exposure made this less likely. Conclusions: Semaglutide use may be associated with severe angioedema within hours of administration. Given the overlapping indications and patient populations, angioedema appearing in patients taking both GLP-1 RAs and ACE inhibitors may become increasingly common and present a diagnostic dilemma. Diagnosis of hypersensitivity to GLP-1 RAs can be supported with history and positive skin testing. Clinicians should be aware that inexperienced patients are at the highest risk of dosing errors. Full article

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infects host cells through the interaction between the spike protein receptor-binding domain (RBD) and the human angiotensin-converting enzyme 2 (hACE2) receptor, which is expressed on epithelial cells in various tissues, including the respiratory tract. Therefore, mucosal immunity in the respiratory tract plays a key role in protection against viral infection. Previously, we demonstrated that intranasal administration of antigens (Ags) conjugated with the M cell-targeting peptide Co4B enhances both mucosal and systemic immune responses. That conjugation with human β-defensin 2 (HBD2) increases neutralizing antibody (Ab) responses. Methods: A recombinant antigen conjugate incorporating both Co4B and HBD2 was designed to enhance immunogenicity. Its immunogenicity was evaluated in mice following intranasal immunization. Antigen-specific antibody responses were measured in serum and bronchoalveolar lavage fluid. T-cell responses were evaluated in lungs and spleens. Protective efficacy was assessed using SARS-CoV-2-susceptible hACE2 knock-in mice. Results: Ag-specific Ab levels increased in both serum and bronchoalveolar lavage fluid of mice immunized intranasally with the conjugate. Especially, T-cell responses were significantly enhanced in the lungs and spleens of immunized hACE2 knock-in mice. In challenge experiments, intranasal administration of the conjugate reduced viral load. Moreover, Siglec F was identified as a potential receptor for Co4B, a previously uncharacterized M cell-targeting ligand. Conclusions: A recombinant viral Ag containing Co4B and HBD2 induces virus-specific humoral and cellular immune responses. Although further optimization of the vaccine formulation and administration strategy is needed, this conjugate shows potential as a platform for improving mucosal and systemic immunity. Full article

Background/Objectives: The ACE2/Ang-(1–7)/Mas receptor axis is a protective, counter-regulatory component of the RAAS that opposes Ang II/AT₁R-mediated vasoconstriction. The present study evaluated the pharmacological effects of Ang-(1–7) in the rat inferior vena cava (IVC), a venous capacitance vessel involved in the regulation of venous return and cardiac preload. We hypothesized that Ang-(1–7) exerts anti-contractile effects in the rat inferior vena cava through activation of potassium channel-dependent mechanisms in venous smooth muscle. Methods: Isolated IVC rings from Wistar rats were studied using organ bath assays. Ang-(1–7) effects were assessed on pre-constriction induced by angiotensin II (Ang II), phenylephrine (PE), endothelin-1 (ET-1), and thromboxane A₂ analog (U46619). Responses were recorded and quantified. Mechanistic involvement of nitric oxide (NO), prostaglandins, soluble guanylate cyclase (sGC), and K⁺ channels was evaluated using specific pharmacological inhibitors. Results: Ang-(1–7) attenuated Ang II-induced contraction. The effect was markedly reduced by tetraethylammonium (TEA), indicating a predominant role of potassium channel-dependent mechanisms in venous smooth muscle. In contrast, inhibition of nitric oxide synthase, soluble guanylate cyclase, or cyclooxygenase had minimal influence. Ang-(1–7) also produced concentration-dependent relaxation in PE-, ET-1-, and U46619-precontracted vessels, demonstrating agonist-dependent anti-contractile activity. Conclusions: Ang-(1–7) exerts significant anti-contractile effects in the rat inferior vena cava primarily through activation of TEA-sensitive K⁺ channels in venous smooth muscle. These findings demonstrate functional activity of the ACE2/Ang-(1–7)/Mas axis in a major venous capacitance vessel and provide mechanistic insight into Ang-(1–7)-mediated modulation of venous tone, supporting further investigation in in vivo models. Full article

Glucagon-like peptide (GLP)-1 receptor (GLP1R) agonists exert a multitude of beneficial cardiovascular effects beyond control of blood glucose levels and obesity reduction. GLP-1R is a G protein-coupled receptor (GPCR), coupling to adenylyl cyclase (AC)-stimulatory Gs proteins to raise cyclic 3′-5′-adenosine monophosphate (cAMP) levels in cells. cAMP exerts various effects mainly via protein kinase A (PKA) and Exchange protein directly activated by cAMP (Epac). Cardiac GLP-1R has been reported to induce atrial natriuretic peptide (ANP) secretion via Epac2, while ANP is known to inhibit aldosterone secretion from adrenocortical zona glomerulosa (AZG) cells. Herein, we tested the effects of the GLP-1R agonist liraglutide on ANP secretion in H9c2 cardiomyocytes and on angiotensin II (AngII)-induced aldosterone secretion. We also examined whether phosphodiesterase (PDE)-4 inhibition with roflumilast could potentiate liraglutide’s effects. We found that liraglutide stimulated ANP secretion from H9c2 cardiomyocytes, an effect potentiated by roflumilast but blocked by AC inhibition. Epac inhibition with ESI-09 also significantly reduced liraglutide-dependent ANP secretion in H9c2 cardiomyocytes. Moreover, application of medium from liraglutide-treated H9c2 cardiomyocytes, but not from control cardiomyocytes, led to suppression of AngII-dependent aldosterone secretion from H295R cells. This effect was blocked by cyclic guanosine monophosphate (cGMP)-dependent protein kinase inhibition (an effector of ANP) in H295R cells, while direct application of liraglutide to these cells failed to suppress AngII-induced aldosterone secretion. Again, aldosterone suppression was more potent when medium from liraglutide plus roflumilast-treated cardiomyocytes was applied to H295R cells. Taken together, these results suggest that roflumilast enhances the adrenocortical aldosterone suppression induced by GLP-1R agonists via cardiac GLP-1R/cAMP/Epac-dependent ANP secretion. Given the cardio-toxic effects of elevated aldosterone levels in the context of various heart diseases, such as post-myocardial infarction heart failure, combination of a GLP-1R agonist drug with a PDE4 inhibitor drug may be more advantageous than either agent alone in treatment of certain cardiovascular diseases. Full article

Background/Objectives: The androgen receptor (AR)-driven transcriptional program plays a pivotal role in the development and progression of prostate cancer. The binding of androgen dihydrotestosterone (DHT) to AR initiates transcriptional activation, thereby altering the transcriptional landscape. DHT-induced long non-coding RNAs (lncRNAs) have been recognized as crucial players in prostate cancer pathogenesis. This study aims to identify and explore the important role of such lncRNAs in prostate cancer. Methods: This study first analyzed transcriptome data from an androgen-dependent cell line, LNCaP, treated with different DHT concentrations and found a batch of lncRNAs exhibiting DHT concentration dependence. TCGA data suggested a correlation between the DHT-induced lncRNA and prostate cancer. Finally, a series of in vivo and in vitro experiments confirmed the effect and mechanism of lncRNA in prostate cancer. Results: AC092718.4 was highly expressed in AR-positive prostate cancer cell lines and tissues, and its expression in patients with Gleason scores 6–9 was significantly higher than in a normal control group. Notably, the expression level of AC092718.4 was upregulated in a concentration-dependent manner with DHT. In vitro experiments revealed that overexpression of AC092718.4 promoted cell proliferation and inhibited cell apoptosis. Conversely, knockdown of AC092718.4 suppressed tumorigenesis in vivo. Furthermore, our investigation into the pathogenetic mechanism demonstrated that AC092718.4 could act as an miRNA sponge for miR-138-5p, attenuating its inhibitory effect on downstream oncogenes, such as FERMT2, RHOC, and HIF1A. These AC092718.4/miR-138-5p/mRNA axes, in turn, facilitated the progression of prostate cancer. Conclusions: For the first time, we demonstrate that AC092718.4 may function as an oncogenic factor in prostate cancer. The AC0927.8.4/miR-138-5p/mRNA axes potentially offer promising diagnostic and therapeutic targets for prostate cancer. Full article

The continued evolution of SARS-CoV-2 has enabled an escape from most monoclonal antibodies, yet a subset of broadly neutralizing antibodies targeting three newly identified super-conserved RBD epitopes—SCORE-A, SCORE-B, and SCORE-C—retains remarkable activity against even the most recent JN.1-derived sublineages. Here, we employed an integrated computational framework combining conformational dynamics, mutational scanning, MM-GBSA binding energetics, and frustration profiling to dissect the molecular mechanisms by which XGI antibodies achieve broad neutralization and resistance to immune escape. Structural analysis revealed that all three SCORE epitopes share a common architecture: a highly conserved, minimally frustrated core that provides stable anchoring, flanked by peripheral regions that accommodate antibody-specific variations. Conformational dynamics showed that SCORE-A antibodies (XGI-183) rigidify the lateral epitope while leaving the RBM partially mobile; SCORE-B antibodies (XGI-198, XGI-203) clamp the RBM apex, directly blocking ACE2; and SCORE-C antibodies (XGI-171) allosterically loosen the RBM loop, impairing receptor engagement indirectly. Mutational scanning identified a hierarchical hotspot organization where primary hotspots (e.g., K356, T500, Y380, T385) are evolutionarily constrained and minimally frustrated, while secondary hotspots (e.g., V503, Y508, S383) are neutrally frustrated and represent the principal sites of immune-driven mutations. MM-GBSA decomposition revealed that van der Waals-driven hydrophobic packing dominates binding, with electrostatic interactions providing auxiliary stabilization. Critically, frustration analysis demonstrated that immune escape hotspots reside precisely in zones of neutral frustration—“energetic playgrounds” that permit mutational exploration without destabilizing the RBD—while minimally frustrated cores are evolutionarily locked. The comparative analysis of conformational versus mutational frustration distributions revealed a unifying principle: aligned neutral frustration yields permissive, escape-prone interfaces; decoupling enables the targeting of constrained cores; and the convergence of minimal frustration in both distributions creates invulnerable interfaces. These findings establish that broad neutralization arises not from ultra-high-affinity anchors but from strategic energy distribution across rigid, evolutionarily informed interfaces, providing a roadmap for designing next-generation therapeutics that target the invulnerable cores of viral surface proteins. Full article

Background: Tumour glycosylation regulates immune modulation and progression, but whether the CRC sialylome—the complete repertoire of sialylated glycans—defines a biologically distinct subtype remains unclear. We investigated how the “sugar code” shapes CRC biology, immunity, and therapeutic response. Methods: Transcriptomic data from three CRC cohorts (TCGA, Sidra-LUMC, and CPTAC-2; n = 988) were batch-corrected and integrated. Single-sample gene set enrichment analysis (ssGSEA) quantified sialyltransferase expression, sialic acid metabolism, EMT, MDR mechanisms, immune phenotypes, and Siglec-associated transcriptional signatures. GSEA, gene ontology enrichment analysis (GOEA), and drug ontology enrichment analysis (DOEA) characterised pathways and identified drug response-associated transcriptional signatures. Results: High sialylome activity defined a genomically stable but clinically advanced CRC subset enriched for left-sided tumours, mucinous histology, MSI, and BRAF mutations. At the transcriptional level, Sialyl-High tumours were associated with a mesenchymal, stromal-remodelling programme accompanied by reduced proliferative activity. They demonstrated enrichment of vesicular trafficking-related pathways alongside reduced representation of canonical efflux-associated programmes. Critically, the sialylome was associated with Siglec-related immune signatures, with sialylated glycan-related gene expression correlating with Siglec receptor expression (CD33 and SIGLEC7/9/10), consistent with an immune-inflamed yet structurally excluded microenvironment. DOEA identified selective enrichment of drug-response signatures related to sialic acid metabolism inhibitors (oseltamivir and Neu5Ac) and glycocalyx-disrupting agents (ginsenosides and soyasaponins). Conclusions: The CRC sialylome is associated with tumour phenotypic variation, including immune-excluded states linked to Siglec-associated transcriptional signatures and patterns consistent with non-canonical drug resistance programmes. These findings position the “sugar code” as a central organising principle in CRC and identify glycan-directed therapies as a promising strategy for the targeting of this aggressive subtype. Full article

Background: A major challenge in antiviral development is the identification of novel virus–host interactions while ensuring therapeutic efficacy and safety. These challenges have renewed interest in phytochemicals derived from medicinal plants as alternative antiviral agents. Objectives: In this study, we investigated the antioxidant, antiviral, and immunomodulatory properties of a Mediterranean Urtica dioica extract (UdE) against SARS-CoV-2 using chemical, biochemical, and in vitro approaches. Methods: The physicochemical properties of UdE were characterized using microtiter assays and HPLC analysis. Cytocompatibility was evaluated in HEK293T, Vero E6, Caco-2, and Calu-3 cell lines while antioxidant activity was assessed using both chemical and cell-based assays. Antiviral activity was evaluated by assessing inhibition of SARS-CoV-2 receptor binding domain (RBD)–ACE2 interaction using ELISA, inhibition of SARS-CoV-2 main protease (Mpro) activity via FRET assay and inhibition of viral entry using SARS-CoV-2 S1 pseudovirus neutralization assay. Results: UdE (100 µg/mL) inhibited RBD–ACE2 binding by 94% and suppressed Mpro activity by 74%, while reducing moderate but significant inhibition of pseudovirus entry (33.6%) at 300 µg/mL dose level in ACE2 expressing HEK293T cells. Immunomodulatory analysis revealed significant suppression of IL-1β and IL-6 production, accompanied by increased TNF-α and IL-8 levels. Conclusions: Collectively, these findings highlight that UdE exhibits multi-target in vitro antioxidant, antiviral, and immunomodulatory activity against SARS-CoV-2; therefore, UdE represents a promising bioactive extract for the management of SARS-CoV-2 infection. Full article

This study reviews the main candidate genes involved in the pathophysiology of Polycystic Ovary Syndrome (PCOS). PCOS is a common endocrine–metabolic disorder in women of reproductive age, characterized by menstrual irregularity, hyperandrogenism, and polycystic ovarian morphology. It is associated with increased metabolic and cardiovascular risk and is a leading cause of infertility. Although its pathophysiology is not fully understood, alterations in the hypothalamic–pituitary–ovarian axis, insulin metabolism, and steroidogenesis have been described. Polymorphisms in genes encoding hormones, enzymes, and receptors in these pathways contribute to clinical variability and ethnic differences, offering potential for early diagnosis and personalized medicine. This review summarizes key candidate genes related to insulin metabolism (INS, INSR, IRS-1), the hypothalamic–pituitary–ovarian axis (LHβ, LHCGR, FSHR, GnRHR, AMH, AMHR2, KISS1, CAPN10), steroidogenesis (CYP11A, CYP17A1, CYP19A1, CYP21, 17β-HSD, SHBG, AR, STAR), and other clinically relevant mechanisms such as obesity, lipid metabolism (PPARG, VDR, FTO), and follicular development (ACE). Full article

Angiotensin-converting enzyme (ACE) inhibitors (ACEis) are one of the most successful drug classes for the treatment of hypertension and the prevention of its cardiovascular complications. ACE activates the pressor hormone angiotensin but also inactivates the vasodilator peptide bradykinin (BK). A rare side effect of ACEis, angioedema (AE), has been proposed to result from pro-inflammatory effects of BK. Novel considerations are offered in this debate: (1) the bradykinin B2 receptor antagonist icatibant has had an inconsistent effect on ACEi-associated AE, but its potency and duration of action are much inferior to those of a novel nonpeptide antagonist of this receptor, deucrictibant. (2) Tissue kallikrein (KLK-1) is an effective kininogenase, particularly abundant in the salivary glands, possibly related to orofacial presentation of ACEi-induced AE. (3) The strongly regulated human kinin B1 receptor, optimally responsive to Lys-des-Arg⁹-BK, is functionally compartmentalized with KLK-1 which produces Lys-BK from kininogens. Chronic treatment with ACEi drugs in laboratory animals induces the expression of vascular B1R that mediates vasodilation. Therefore, ACEi-AE may be largely or completely initiated by KLK-1. Inhibitors of this protease or combined antagonists of both kinin receptor subtypes may be useful for the management of this condition. Full article

One of the most critical aspects of post-acute COVID-19 syndrome (PACS) and post-acute COVID-19 vaccination syndrome (PACVS) is the presence of autoantibodies. These autoantibodies are directed against various receptors in the autonomic and cardiovascular systems, including those targeting proteins of the renin–angiotensin system (RAS). The RAS plays a central role in regulating vascular homeostasis, inflammation, and endothelial function. During SARS-CoV-2 infection, the interaction of the spike (S) protein with angiotensin-converting enzyme 2 (ACE2) can alter the balance of the RAS, favoring an imbalance towards the ACE/Angiotensin II/AT1R axis, known for its pro-inflammatory, pro-thrombotic, and vasoconstrictive properties. Similar pathological mechanisms also come into play in response to vaccinations that use the S protein as an antigen. Studies conducted by other groups and us on patients with PACS and PACVS have revealed the presence of autoantibodies directed against these RAS components and the mechanisms by which these antibodies can worsen the clinical situation. In particular, anti-ACE2, presumably formed by the anti-idiotype network or molecular mimicry, is correlated with PACVS symptoms in many patients. Furthermore, the presence of anti-MAS1 antibodies can reduce the efficiency of the ACE2/Angiotensin-(1–7)/MAS1 axis, which normally acts as a counter-regulator. Considering this evidence, an analysis of RAS molecules and the autoantibodies implicated in reactions to them may be useful for evaluating a state of persistent dysregulation associated with post-vaccination symptoms such as asthenia, headache, skin edema and bruising, cardiovascular alterations, and neurovegetative manifestations. Finally, we offer insights into diagnosing these multifaceted syndromes and working hypotheses to guide research into possible therapeutic approaches. Full article

Background: Despite the effectiveness of current SARS-CoV-2 vaccines, the genetic variability of the viral target has led to the emergence of variants capable of evading vaccine-induced protection. To ensure broader and more durable protection, we investigated the efficacy of a novel vaccine strategy. Methods: This vaccine utilizes the highly conserved nucleocapsid (N) protein as its primary antigen, rather than the spike (S) protein. It incorporates the Papaya Mosaic Virus (PapMV) nanoparticle, a Toll-like receptor (TLR) 7/8 agonist with intrinsic adjuvant properties, as a vaccine platform. Results: The vaccine formulations, comprising PapMV nanoparticles and the N antigen covalently or non-covalently attached to the PpaMV nano, generated robust humoral (antibody) and cellular (T-cell) immune responses. Protective efficacy was evaluated in K18-hACE2 transgenic mice challenged with either the ancestral SARS-CoV-2 strain or the Omicron XBB.1.5 variant. In both cases, the vaccine significantly reduced inflammation and viral titers in the lungs of vaccinated animals. Conclusions: These results highlight the potential of this PapMV-N vaccine to induce broad protection against diverse SARS-CoV-2 variants. Full article