Search Results (200)

Background: Neuroinflammation contributes to the etiopathology and symptom severity of neurodegenerative and neuropsychiatric disorders. Glial cells, especially microglia and astrocytes, play a crucial role in neuroinflammation. It has been reported that ginseng (Panax ginseng) and its bioactive component ginsenoside Rg1 exhibit anti-inflammatory effects and can improve cognitive performance in various models. However, the exact underlying mechanisms remain unclear. Methods: Astrocyte–microglia co-culture models simulating physiological (M5, 5–10% microglia) and pathological/inflammatory (M30, 30–40% microglia) conditions were treated with different concentrations of ginsenoside Rg1 (15, 30, 45 µM) or ginseng extract (derived from Korean red ginseng) at low (12.5, 25, 37.5 µg/mL) or high doses (125, 250, 375 µg/mL) for 24 h. Cell viability was assessed using the MTT assay while microglial reactivity was examined using immunocytochemistry. Astrocytic gap-junctional coupling was investigated using the scrape-loading method, and connexin 43 (Cx43) expression was analyzed using immunocytochemistry and Western blot. Results: Both Rg1 and low-dose ginseng extract reduced microglial activation under inflammatory conditions by promoting a shift in microglia from an activated to homeostatic (resting) phenotype. Rg1 preserved astrocytic gap-junctional function by preventing the inflammation-induced downregulation of Cx43 expression and enhancing Cx43-mediated gap-junctional intercellular communication. Rg1 caused a significant reduction in glial cell viability, but only at high concentrations (30 and 45 µM), under inflammatory conditions. High-dose ginseng extract showed a significant concentration-dependent reduction in glial cell viability under physiological and pathological conditions, without comparable anti-inflammatory benefits. Conclusions: This study demonstrates that low-dose ginseng and its active compound Rg1 exert anti-inflammatory effects by modulating astrocytic coupling and microglial reactivity. These results provide a novel therapeutic perspective for the use of ginseng in the treatment of neurodegenerative and neuropsychiatric diseases related to neuroinflammation. Full article

Ovarian granulosa cells (GCs) ensure proper follicular development and oocyte maturation through gap-junction-mediated intercellular communication. Zearalenone (ZEA), a mycotoxin with estrogen-like activity, specifically targets and impairs ovarian function. Most existing studies have focused on ZEA-induced apoptosis in GCs, but whether ZEA disrupts gap junctions in ovarian GCs remains unclear. Therefore, the aim of this study was to investigate whether and how ZEA induces gap junction injury in ovine ovarian GCs, with a particular focus on the roles of G protein-coupled receptor 30 (GPR30), oxidative stress, and the NLRP3 inflammasome. In the present study, primary ovine ovarian GCs were isolated, cultured, and treated with different concentrations of ZEA to establish a gap junction injury model, and specific inhibitors/antagonists were used to investigate the underlying mechanisms. The results showed that ZEA decreased granulosa cell viability and significantly inhibited the expression of the gap junction proteins Connexin 43 (Cx43) and Connexin 37 (Cx37) in a concentration-dependent manner. ZEA treatment also significantly upregulated the expression of the NOD-like receptor familypyrindomain containing 3 (NLRP3) inflammasome-related proteins (NLRP3, ASC, Cleaved Caspase-1, and the downstream pro-inflammatory cytokine IL-1β) in a concentration-dependent manner. Pretreatment with the NLRP3-specific inhibitor MCC950 significantly reversed ZEA-induced downregulation of Cx43 and Cx37 and effectively blocked NLRP3 inflammasome activation, indicating that NLRP3 is a key target in ZEA-induced gap junction injury. Further experiments confirmed that ZEA treatment significantly increased oxidative stress levels in granulosa cells; pretreatment with the reactive oxygen species (ROS) scavenger N-acetylcysteine (NAC) restored the ZEA-induced downregulation of Cx43 and Cx37 and suppressed NLRP3 inflammasome activation, suggesting that ROS acts as an upstream regulator of NLRP3 inflammasome activation. Moreover, ZEA treatment altered GPR30 expression levels, and pretreatment with the GPR30 antagonist G15 effectively inhibited ZEA-induced ROS production, NLRP3 inflammasome activation, and downregulation of Cx43/Cx37, indicating that ZEA exerts its effects through functional activation of GPR30. Collectively, ZEA activates the GPR30 receptor, induces ROS accumulation in granulosa cells, and subsequently triggers NLRP3 inflammasome activation, ultimately leading to downregulation of Cx43 and Cx37 and gap junction dysfunction. This study reveals a previously unrecognized molecular mechanism by which ZEA induces gap junction injury in ovarian GCs, providing potential therapeutic targets and a theoretical basis for preventing ZEA-induced ovarian dysfunction and improving animal reproductive health. Full article

Severe traumatic brain injury (TBI) is one of the leading causes of mortality and disability worldwide. To date, there are no clinically effective neuroprotective agents. Biomaterials that combine structural support for damaged tissue with a depot for therapeutic agents may represent a key solution to this problem. To evaluate the neuroprotective potential of a collagen matrix derived from the jellyfish Rhizostoma pulmo (R. pulmo) and modified with sodium thiosulfate (Na₂S₂O₃) as an hydrogen sulfide (H₂S) donor in a bioengineered platform for the treatment of severe TBI. Comprehensive characterization of the collagen matrix (electrophoresis, fluorescence microscopy), its implantation in a mouse model of severe TBI, and subsequent morphological, histological, ultrastructural, and immunohistochemical analyses of connexin 43 (Cx43) and p53 protein (p53) were performed. In addition, molecular dynamics simulations of the interactions between sulfur-containing compounds and target proteins were conducted. The effects were compared with inhibition of endogenous H₂S synthesis using aminooxyacetic acid (AOAA). The collagen matrix retains the properties of type I collagen and forms a three-dimensional porous structure with high hydrophilicity and biocompatibility. Implantation ensures effective defect filling, reduces cystic degeneration, and preserves cortical structure. Modification with Na₂S₂O₃ results in a significant reduction in both nuclear and cytoplasmic accumulation of p53, prevention of Cx43 dysregulation, a decrease in the proportion of damaged neurons and inflammatory infiltration, and preservation of tissue ultrastructure. In contrast, inhibition of CBS with AOAA exacerbates pathological changes. Molecular modeling demonstrated that S₂O₃²⁻ is capable of forming stable electrostatic interactions with domains of p53 and Cx43 under conditions of acidosis and elevated Ca²⁺. A collagen matrix derived from R. pulmo and modified with Na₂S₂O₃ represents a promising biodegradable platform that combines structural support with local H₂S-dependent regulation of key mechanisms of secondary brain injury. This approach provides a multilevel neuroprotective effect and opens new opportunities for the development of therapeutic implants for severe TBI. Full article

Ischemic diseases are characterized by the functional collapse of endothelial cells (ECs) triggered by insufficient tissue perfusion. Given that mitochondria serve as the metabolic hub of ECs, their homeostatic imbalance, which is manifested by adenosine triphosphate (ATP) depletion, reactive oxygen species (ROS) bursts, and mitochondrial permeability transition pore opening, serves as the initiating factor driving impaired angiogenesis and tissue necrosis. In this study, we engineered an integrated nanosystem (Tan-CDs@AS-IV) by transforming Tanshinone into antioxidant carbon dots to encapsulate Astragaloside IV, achieving multi-level synergistic regulation of mitochondrial function. Our results demonstrate that Tan-CDs@AS-IV possesses superior structural stability and cellular internalization capabilities, significantly enhancing the migration and tubulogenesis of ECs under ischemic stress. Mechanistically, Tan-CDs@AS-IV effectively scavenges mitochondrial ROS and restores membrane potential and ATP production. Crucially, the nanosystem orchestrates mitochondrial biogenesis via peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) upregulation while simultaneously facilitating intercellular mitochondrial transfer through Connexin 43 (Cx43)-mediated gap junctions. This synergistic “endogenous amplification and intercellular replenishment” model establishes a robust mitochondrial quality control relay. By reconstructing cellular energy homeostasis, this study provides a novel nanoengineering strategy for the targeted therapy of ischemic diseases. Full article

Pancreatic adenocarcinoma remains a highly lethal malignancy with limited effective treatment options, largely due to late-stage detection and rapid progression to metastatic disease. Therapeutic strategies capable of targeting both pre-metastatic and metastatic tumors are critically needed. In this study, we evaluated a combination therapy consisting of non-thermal plasma (NTP), a generator of reactive oxygen and nitrogen species, and the hypoxia-activated prodrug tirapazamine (TPZ). We further investigated whether sulforaphane (SF), a bioactive phytochemical, could further enhance therapeutic efficacy. NTP and TPZ produced strong cytotoxic effects as single agents and demonstrated additive to synergistic activity when combined, reducing viability by 87% in pre-metastatic BxPC-3 cells and achieving near-complete elimination of metastatic AsPC-1 cells. The addition of sulforaphane (10 µM) further enhanced cytotoxicity across all treatment conditions, with Bliss independence analysis indicating additive to synergistic interactions depending on cell line and treatment combination. Sulforaphane-mediated enhancement occurred without restoration of connexin 43 expression or coordinated reversal of epithelial-to-mesenchymal transition markers, and treatments did not induce N-cadherin upregulation or suggest acquisition of invasive characteristics. Together, these findings support NTP + TPZ as a potent combinatorial strategy for pancreatic adenocarcinoma and identify sulforaphane as an effective adjunct that enhances cytotoxic efficacy through mechanisms that remain to be fully elucidated. Full article

Background/Objectives: Clinical application of Doxorubicin (Doxo) is limited by cardiotoxicity, a process strongly associated with an interplay between oxidative stress and inflammatory signaling, particularly Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation and Nucleotide oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome engagement. Identifying strategies capable of mitigating these interconnected pathways is of critical importance in cardio-oncology. Simvastatin (SIM) is a promising option since it modulates oxidative stress, inflammation, and cell death through its pleiotropic effects, so this study aimed to evaluate whether SIM attenuates Doxo-induced inflammatory responses. Methods: Human Cardiomyocyte (HCM) cells were pre-treated with SIM (10 µM) for 4 h and then co-exposed to SIM and Doxo (1 µM) for 20 h. Cytofluorimetric analysis was used to evaluate inducible nitric oxide synthase (iNOS), Connexin 43 (Cx43), and Cx43 phosphorylated at Serine 368 (p^S368Cx43) levels. Real-time qPCR was performed to evaluate iNOS gene expression, while Nitric oxide (NO) release was evaluated by spectrophotometric analysis. Interleukin (IL)-1β, IL-18, IL-6, tumor necrosis factor alpha (TNF-α) production, and NLRP3 levels were evaluated by means of ELISA assay. Expression levels of inhibitor of nuclear factor kappa B alpha (IκB-α), Caspase-1, and Gasdermin D (GSDMD) were evaluated by Western Blot analysis. Nuclear translocation of NF-κB was evaluated by immunofluorescence assay. Results: In our experimental model, SIM significantly (p < 0.01) reduced Doxo-induced nitrite release, as well as iNOS gene expression (p < 0.05) and protein levels (p < 0.01). SIM also markedly attenuated Doxo-induced NF-κB signaling, pro-inflammatory cytokines production (TNF-α and IL-6, p < 0.01), and inflammosome-related responses (cleaved caspase-1, IL-1β, N-terminal domain of GSDMD), and NLRP3 expression p < 0.05). Additionally, SIM significantly attenuated the overexpression of Cx43 and its phosphorylated form (p^S368Cx43), which are responsible for impairing intercellular communication and electrical coupling in cardiomyocytes and contribute to arrhythmias and conduction abnormalities characteristic of acute Doxo-induced cardiotoxicity. Conclusions: Overall, these findings demonstrate that SIM exerts a multifaceted cardioprotective effect against Doxo-induced injury, thereby targeting interconnected inflammatory and pro-arrhythmic pathways implicated in Doxo cardiotoxicity. Full article

Background: Connexins (Cx) are a family of transmembrane proteins that form gap junctions and connexin hemichannels (HCs), enabling direct intercellular communication within the nervous system. Connexin 43 (Cx43), the principal astrocytic connexin, exhibits a context-dependent dual role: under physiological conditions it maintains tissue homeostasis and metabolic support, whereas under pathological conditions excessive activation of Cx43 hemichannels promotes neuroinflammation, excitotoxicity, blood–brain barrier disruption, and secondary neural tissue damage. Other connexin isoforms also contribute to the pathogenesis of neurological and psychiatric disorders through alterations in neuronal synchronization, glial signaling, and myelin integrity. Objective: To systematize current evidence on the role of key connexin isoforms in acute nervous system injuries—including stroke, traumatic brain injury, spinal cord injury, and peripheral nerve injury—as well as chronic disorders such as neurodegenerative diseases, epilepsy, and psychiatric disorders, with particular emphasis on the functional duality of connexin channels and the therapeutic potential of their selective modulation. Methods: A systematic literature search was conducted in the PubMed, Scopus, and Web of Science databases in accordance with the PRISMA framework and the PRISMA Extension for Scoping Reviews guidelines. The review included data from experimental models, postmortem brain studies, genetic association analyses, and pharmacological intervention studies. The retrieved studies were screened, assessed for eligibility, and integrated using a qualitative narrative synthesis approach. Results: In acute neural injuries, hyperactivation of Cx43 hemichannels amplifies inflammatory signaling, edema formation, and neuronal death, whereas selective HCs inhibitors reduce lesion volume and improve functional outcomes in experimental models. Connexin 36 (Cx36) contributes to cortical spreading depolarization and seizure propagation, while Connexin 32 (Cx32) and Connexin 47 (Cx47) are critically involved in oligodendrocyte function and white-matter demyelination. In PNI, Cx43 upregulation contributes to neuropathic pain, whereas mutations in Cx32 cause hereditary demyelinating neuropathies. In neurodegenerative diseases—including Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis—Cx43 hemichannel activity promotes neuroinflammation and pathological protein accumulation, while reduced Cx32/Cx47 expression disrupts metabolic support of axons. In psychiatric disorders such as major depressive disorder, bipolar disorder, and schizophrenia, decreased astrocytic connexin expression (Cx43 and Cx30) has been associated with impaired glial–neuronal communication and cognitive–emotional dysfunction. In epilepsy, increased Cx43/Cx30 expression contributes to neuronal hypersynchronization and blood–brain barrier dysfunction, whereas selective hemichannel blockade suppresses seizure activity. Conclusions: Cx—particularly Cx43—occupies a central position in the molecular mechanisms of secondary neural injury and network dysfunction. The dual functional properties of gap junctions and hemichannels determine their context-dependent effects across neurological and psychiatric diseases. Selective inhibition of pathological HCs activity shows significant neuroprotective and anticonvulsant potential and represents a promising direction for the development of targeted therapeutic strategies. Further studies are required to determine optimal therapeutic time windows, tissue-specific effects, and the long-term safety of Cx modulation. Full article

Traumatic brain injury (TBI) initiates a cascade of molecular and cellular reactions leading to long-term disturbances of neuronal and glial homeostasis. One of the key mechanisms of secondary injury is a pathological increase in intracellular Ca²⁺ concentration. Parvalbumin (PV) plays an important role in the regulation of Ca²⁺ homeostasis in neurons. In turn, connexin 43 (Cx43) is the principal protein of astrocytic gap junctions (GJs), which ensure neuroglial communication. The spatiotemporal changes in these proteins and the mechanisms of their interaction after TBI remain insufficiently studied. In the present study, a comprehensive analysis of the expression, localization, and spatial organization of PV and Cx43 in the cerebral cortex following TBI was performed. In intact tissue, PV was localized predominantly in neurons, whereas Cx43 formed typical punctate structures of astrocytic GJs. Twenty-four hours after TBI, a sharp activation of PV with pronounced nuclear translocation was observed against the background of a catastrophic decrease in Cx43 expression, accompanied by a reduction in the number of NeuN⁺ neurons and signs of apoptosis. However, after 7 days, a mirror-opposite effect was detected, characterized by decreased PV expression and increased Cx43 levels with its aggregation into cluster-like structures, as well as partial restoration of NeuN immunoreactivity. In addition, molecular dynamics simulations demonstrated that the stability of the PV–Cx43 complex is determined by the presence of Ca²⁺ and physiological pH, whereas acidosis and Ca²⁺ overload destabilize their interaction. Taken together, these results reveal a phase-dependent mirror-opposite pattern of PV and Cx43 expression and localization and emphasize the key role of Ca²⁺- and pH-dependent neuroglial interactions in TBI. Full article

Melanoma is a highly malignant neoplasm of the skin with early metastatic spread and increasing incidence worldwide. Although there are significant therapeutic advances in immunotherapy, especially with the checkpoint inhibitors targeting PD-1 and CTLA-4, challenges such as treatment-related toxicities, a heterogeneous response to therapy, and drug resistance continue to exist. There are unmet needs for novel therapeutic strategies and/or approaches to complement the existing treatment options. Potential targets for future melanoma treatment are the gap junction proteins, connexins, which show an altered pattern of regulation during melanoma progression. In this review, we highlight the regulation of gap junctions during melanoma progression and the characterization of gap junctions as tumor suppressors during early-stage tumor development and then the reversion to enhancers of tumor metastasis during late-stage melanoma progression. We provide a comprehensive overview of gap junctions in the skin and how the connexin proteins, which comprise gap junctions, are alternatively regulated in melanoma progression. Connexins are protein channels in the human body that consist of 21 isoforms. These isoforms form gap junctions that provide important intercellular signaling and permeability channels. Each connexin protein consists of four transmembrane domains and a C-terminal tail, which is an important part of its function and regulation. Permeants of gap junctions include signaling molecules such as cyclic AMP and inositol triphosphate which are linked to key cellular behaviors such as proliferation and migration, making them essential for several tumor-related processes. At least ten connexin isoforms are found in normal skin. Connexin 43 (Cx43) is classified as the most prevalent isoform while Connexin 26 (Cx26) has been reported to be more specialized with restricted expression patterns. Cx43 and Cx26 regulate the growth, differentiation, and repair of the epidermis after injury. Evidence suggests that connexins have a stage-related function in melanoma. Loss of connexin expression and gap junctional intercellular communication is linked to tumor suppression and loss of differentiation in early-stage melanoma, while re-expression or overexpression of specific connexins, notably Cx43, may promote metastasis through enhanced tumor–stromal interactions and increased motility in late-stage melanoma. Such opposing actions of connexins support their candidacy as biomarkers and therapeutic targets. Understanding the dual-stage related functions of connexins in melanoma development and progression may lead to less cytotoxic and more efficient future therapeutic approaches. Full article

We studied the expression of connexin 43 (Cx43) and pannexin 1 (PANX1) in different cellular populations of the kidneys of diabetic mice and diabetic and non-diabetic patients, to evaluate their role as potential therapeutic targets in diabetic kidney disease (DKD). A combination of a low dose of streptozotocin and a high-fat diet (HFD) was used to induce a type 2 diabetes model (DM2) in mice. Kidney tissues from diabetic (n = 9) and control patients (n = 11) who underwent nephrectomy were collected. Tissues from mice and humans were processed for double immunofluorescence, using antibodies against Cx43, phosphorylated Cx43 (pCx43) or PANX1 and markers for specific cell populations: endothelium (CD31/PECAM1); pericytes/mesangium (PDGFRB); podocytes (nephrin/synaptopodin); proximal tubules and collecting ducts (aquaporin 2). The results showed a significant decrease in the expression of pCx43 in PDGFRB-immunoreactive mesangium in diabetic patients compared to the control group (p < 0.0001). This contrasted with an increase in pCx43 in pericytes of diabetic mice (p = 0.1). However, we found a general decrease in Cx43 protein expression in diabetic mouse kidneys (p < 0.05). We also found a decrease in the expression of PANX1 in endothelial cells of diabetic patients (p < 0.05) and a significant increase in PANX1 expression in cells expressing PDGFRB (p < 0.05). Expression of PANX1 in endothelium (r = −0.50; p < 0.05) and pCx43 in the mesangium (r = −0.65; p < 0.01) correlated negatively with the percentage of sclerotic glomeruli. The expression and activation of Cx43 and the expression of PANX1 are altered in distinct populations of renal cells during long-term type 2 diabetes mellitus, especially cells of the vascular wall. This may indicate their role in the pathophysiological processes of DKD. Therefore, connexin and pannexin channels could be considered as possible therapeutic targets in the prevention and treatment of diabetic kidney disease. Full article

Following the downregulation of testicular endocrine and germinative function by slow-release gonadotropin-releasing hormone (GnRH)-agonist implants, testicular functions are quickly restored after implant removal. As an intact blood–testis barrier (BTB) is crucial for normal spermatogenesis and its integrity is FSH- and androgen-dependent, alterations in the BTB gene and protein expressions during downregulation and subsequent restart seem inevitable. We investigated occludin (OCLN), claudin (CLDN) 3, 5, 11, and connexin (CX) 43 mRNA-, and CLDN11 and CX43 protein expressions during GnRH implant-induced downregulation (W0) and restart of spermatogenesis after implant removal (week, W, 3–12). Untreated juvenile (JG) and adult dogs (CG) served as controls. Sertoli cells were significantly affected by treatment (reduced nuclear area, OCLN, and CLDN5 expressions). All investigated genes (except CLDN3) differed significantly during restart (W0–12) compared with CG (p < 0.05). CLDN11 and CX43 immunopositive staining was absent or diffuse cytoplasmic at downregulation and relocated at W9, indicating disruption and subsequent restorage of BTB. As W0 and JG differed considerably, our results suggest that the model cannot mimic puberty. In conclusion, GnRH implant-induced long-term gonadotropin suppression disrupts testicular CX43 and CLDN11 distribution and changes gap and tight junction mRNA expression. Treatment effects are reversible suggesting re-establishment of the BTB. Full article

Plant extracts are rich in various bioactive compounds, such as polyphenols, flavonoids, tannins, terpenoids, phenolic acids, saponins, alkaloids, and polysaccharides. Antioxidant polyphenols are increasingly attracting attention, not only as dietary components but also as valuable food industry byproducts. Resveratrol, present in a wide range of plants, is well recognized for its diverse biological activities, including antioxidant, antitumor, cardioprotective, and neuroprotective effects. Given the importance of intercellular communication in these physiological processes, gap junctions (GJs) composed of connexin (Cx) family proteins are of particular interest because they provide a direct pathway for electrical and metabolic signaling and are key players in maintaining normal organ function and cell development. Aberrations of GJ intercellular communication (GJIC) may result in the progression of cardiovascular and neurological diseases and tumorigenesis. Cx43 and Cx45 play crucial roles in cardiac excitation and contraction, and alterations in their expression are associated with disrupted impulse propagation and the development of arrhythmias. In this study, for the first time, we performed a comparative analysis of the effect of resveratrol on Cx43 and Cx45 GJIC using molecular modeling, a dual whole-cell patch-clamp technique to directly measure GJ conductance (g_j), and other approaches. Our results revealed that resveratrol accomplished the following: (1) inhibited GJ g_j in Cx43- but enhanced it in Cx45-expressing HeLa cells; (2) exerted dose- and time-dependent changes in Cx expression and plaque size; (3) reduced cell viability and proliferation; (4) and altered Cx43 phosphorylation patterns linked to gating and plaque stability. Overall, resveratrol modulates GJIC in a dose-, time-, and connexin type-specific manner. Full article

Anterior cruciate ligament (ACL) rupture causes joint instability and increases the risk of osteoarthritis due to the ligament’s limited healing capacity. Silk, particularly from Bombyx mori, combines high cytocompatibility with robust biomechanical properties. Its main components are fibroin and sericin, with the latter usually being removed to reduce immunogenicity and improve biocompatibility. Silk threads were processed either as raw silk (designated as “untreated”) or subjected to a patented degumming procedure (DE102021118652A1) to obtain purified silk. Both variants were used alone or in combination with poly(L-lactic acid-co-caprolactone) (P(LA-CL)) fibers, yielding four scaffold groups: untreated silk, purified silk, untreated silk/P(LA-CL), and purified silk/P(LA-CL). Three-layer scaffolds were fabricated using a zigzag embroidery pattern. Structural analysis revealed scaffold porosity of ≈38% for silk, ≈46% for purified silk, and up to ≈70% for scaffolds containing P(LA-CL). Uniaxial tensile testing showed that purified silk scaffolds achieved the highest maximum force at break (≈684 N), whereas elongation at maximum force was limited in the hybrid scaffolds—silk/P(LA-CL) ≈ 28% and p-silk/P(LA-CL) ≈ 32%—despite the high intrinsic extensibility of P(LA-CL). All scaffolds supported cell adhesion and showed no cytotoxicity. P-silk and p-silk/P(LA-CL) scaffolds exhibited the highest fibroblast adherence and pronounced paxillin expression, indicating strong cell–material interactions. Gene expression of ligament-related ECM components and connexin 43 was maintained across all groups. These results demonstrate that embroidered silk fibroin scaffolds provide a reproducible architecture with tunable porosity and mechanical properties, supporting fibroblast colonization and ligament-specific ECM expression. Such scaffolds represent promising candidates for ACL tissue engineering and future graft development. Full article

Post-COVID cardiac complications have emerged as a significant and persistent clinical concern, yet their underlying mechanisms remain poorly understood. Animal models can act as proxies to investigate the pathophysiology of the human, post-acute sequelae of SARS-CoV-2 infection (PASC). The aim of this experimental study was to evaluate the expression of inflammatory biomarkers in cardiac tissue 28 days after SARS-CoV-2 infection in a female hACE2 mouse model, with a focus on chemokine-mediated immune activation. Twelve female C57BL/6 hACE2 mice were infected with the Omicron variant (BA.1.17 lineage) of SARS-CoV-2, and eleven non-infected mice served as controls. Cardiac tissue was analyzed via Western blot for markers of innate immune activation (TLR4, MyD88, NF-κB) and pro-inflammatory cytokines (IL-6, IL-18, IL-1β, TNF-α, CD11d). Cardiac tissue injury markers (iNOS, PAI-1 and Connexin43) were also analyzed. Compared to non-infected mice, cardiac tissue from infected mice showed significantly higher expression of IL-6 (p = 0.028), indicating an inflammatory state, and CD11d (p = 0.016), suggesting an inflammatory stage accompanied by sustained activation of chemokine-mediated inflammatory signaling. No significant differences in TLR4 (p = 0.340), MyD88 (p = 0.410), NF-κB p65 (p = 0.780), IL-18 (p = 0.548), IL-1β (p = 0.455), and TNF-α (p = 0.125) expressions were observed Similarly, no changes in cardiac damage markers (iNOS: p = 0.4684; PAI-1: p = 0.5345; Connexin 43: p = 0.2879) were found. The results of this experimental study would support the hypothesis of persistent low-grade inflammation as a contributor to post-COVID cardiac sequelae in females that is not accompanied by severe tissue damage, as also observed in clinical studies. This study also reinforces the need for studies evaluating the functional and structural evolution of the myocardium after an acute SARS-CoV-2 infection. Full article

Cardioprotection refers to the natural capacity of heart tissue to resist damage under conditions such as ischemia–reperfusion and various metabolic stresses. First identified in the phenomenon of ischemic preconditioning, the concept has since broadened to encompass other triggers of protective signaling, including hypoxia, temperature shifts, and a wide range of pharmacological compounds. This expansion indicates the presence of common molecular pathways and defense mechanisms. Known intracellular contributors to cardioprotection involve numerous factors, such as protein kinases, the reperfusion injury salvage kinase (RISK) cascade, the Survivor Activating Factor Enhancement (SAFE) pathway, hypoxia-inducible factor-1α (HIF1α), microRNAs, and Connexin 43, among others. These components are crucial in initiating downstream signaling, promoting the expression of protective genes, optimizing mitochondrial function, and regulating cytosolic and protein processes to maintain cardiac resilience. Key end-effectors include SUR2A, a regulatory subunit of sarcolemmal ATP-sensitive potassium (KATP) channels, autophagy, and mitochondria. Central mechanisms, such as modulation of the mitochondrial permeability transition pore and activation of KATP channels, play essential roles in the cardioprotective response. Although significant progress has been made in mapping these networks, many facets remain poorly understood. One of the most pressing challenges is to translate this knowledge into practical therapies and eventually create clinically applicable strategies to protect the heart. Full article