Search Results (10,434)

Ultraviolet (UV) irradiation stimulates melanogenesis in melanocytes and melanin transfer to keratinocytes, where the former is mediated by pleiotropic factors such as SCF, α-MSH, and endothelin-1 (ET-1) secreted by keratinocytes. Therefore, the interaction between melanocytes and keratinocytes after UVB exposure appears to be critical to stimulating melanogenesis. The factors that are responsible for inflammation, one of the key biological processes, are crucial to forming the chronic inflammatory microenvironment in solar lentigines (hereafter called age spots). While chronic inflammation is thought to be involved in hyperpigmentation, the molecular mechanisms through which microinflammation affects melanocyte activation in age spots have not been elucidated. In our study, immunohistochemical analysis showed that the expression of the inflammatory factor IL-6R is enhanced in age spots. Specifically, in cultured keratinocytes irradiated with 10 mJ/cm² UVB, the expression of IL-6R was upregulated in UVB exposure- and age-dependent manners, and the co-culture of melanocytes with UVB-irradiated keratinocytes further demonstrated that melanocyte dendrites increased in length and number in a keratinocyte-age-dependent manner. Moreover, the suppression of IL-6R function in keratinocytes by an IL-6R-specific neutralizing antibody, Tocilizumab, inhibited melanocyte dendricity. These results indicate that the age- and UVB-dependent upregulation of IL-6R in keratinocytes stimulates melanocyte dendricity, which may also contribute to excessive melanin deposition in age spots. Full article

Endometriosis involves oestrogen-dependent chronic inflammation and the abnormal proliferation of ectopic endometrial tissue. Conventional hormonal therapies suppress systemic oestrogen, but do not fully address local oxidative and inflammatory signalling. This review provides a mechanistic synthesis of recent molecular evidence. This evidence is on four FDA-recognized (Food and Drug Administration) medicinal plants. These are Curcuma longa, Zingiber officinale, Glycyrrhiza glabra, and Silybum marianum. The review highlights their capacity to modulate key intracellular pathways. These pathways are implicated in endometriosis. The review covers the integration of phytochemical-specific actions within NF-κB- (nuclear factor kappa-light-chain-enhancer of activated B cells), COX-2-(Cyclooxygenase-2), PI3K/Akt-(PI3K/Akt signaling pathway), Nrf2/ARE-(Nuclear factor erythroid 2–related factor 2) and ERβ-(Estrogen receptor beta) mediated networks, which jointly regulate cytokine secretion, apoptosis, angiogenesis and redox balance in endometrial lesions. Curcumin downregulates COX-2 and aromatase while activating Nrf2 signalling, shogaol from ginger suppresses prostaglandin synthesis and induces caspase-dependent apoptosis, isoliquiritigenin from liquorice inhibits HMGB1-TLR4–NF-κB (High Mobility Group Box 1, Toll-like receptor 4) activation, and silymarin from milk thistle reduces IL-6 (Interleukin-6) and miR-155 (microRNA-155) expression while enhancing antioxidant capacity. Together, these phytochemicals demonstrate pharmacodynamic complementarity with hormonal agents by targeting local inflammatory and oxidative circuits rather than systemic endocrine axes. This mechanistic framework supports the rational integration of phytotherapy into endometriosis management and identifies redox-inflammatory signalling nodes as future translational targets. Full article

Glycosaminoglycans (GAGs), also named ‘mucopolysaccharides’, are nodal constituents of the connective tissue matrix which go through synthesis, demolition, and reconstruction within several cellular structures: an abnormal GAG catabolism is the basis of progressive intra-lysosomal accumulation of non-metabolized GAGs, defining all mucopolysaccharidoses (MPS), protean disorders characterized by physical abnormalities and multi-organ failure depending on the specific site of non-renewable GAGs stored. A severe cognitive decline is typically observed in the Sanfilippo syndrome, which corresponds to MPS type III, a group of four inherited neurodegenerative diseases resulting from the lack of specific enzymes involved in heparan sulfate (HS) metabolism. As a consequence, the storage of partially degraded HS fragments within lysosomes of the central nervous system elicits chain inflammatory reactions involving the NLRP3-inflammasome in microglia and astrocytes, which cease their homeostatic and immune functions and finally compromise neuron survival. This article provides an overview of the neuroinflammatory picture observed in children with MPS type III, postulating a role of HS accumulation to prime innate immunity responses which culminate with pro-inflammatory cytokine release in the brain and highlighting the relevance of interleukin-1 as a main contributor to neuroinflammation. Full article

Background: Pseudomonas aeruginosa infection is a major driver of morbidity and mortality in cystic fibrosis (CF), yet disease severity varies widely among people with CF (pwCF). This clinical heterogeneity suggests the involvement of host genetic modifiers beyond CFTR. We previously identified sphingosine 1-phosphate receptor 1 (S1PR1) as a candidate gene associated with susceptibility to P. aeruginosa. Here, we investigated its role in modulating airway epithelial responses to infection. Methods: Using CRISPR/Cas9, we generated S1PR1-knockout bronchial epithelial cells with (IB3-1) and without (C38) CFTR mutations. We assessed cell viability, cytotoxicity, and interleukin-8 secretion following exposure to P. aeruginosa exoproducts. S1PR1 protein expression was evaluated in lung tissue from pwCF and non-CF individuals using immunohistochemistry. Results: S1PR1-mutant cells produced truncated, non-functional peptides. In CFTR-mutant cells, S1PR1 loss reduced viability, increased cytotoxicity, and significantly enhanced interleukin-8 production in response to P. aeruginosa exoproducts. These effects were not observed in CFTR-competent cells. Notably, S1PR1 protein levels were markedly lower in lung tissue from pwCF compared to non-CF individuals. Conclusions: S1PR1 deficiency exacerbates epithelial damage and inflammatory responses to P. aeruginosa in CF models. These findings highlight S1PR1 as a potential contributor to infection severity and a promising target for therapeutic strategies in pwCF. Full article

In this study, we investigated the role of mitochondrial and sarcolemmal ATP-sensitive potassium channels (mKATP and sKATP, respectively) in the mechanisms of cardioprotection afforded by a combination of Lactobacillus acidophilus (LA-5) and Bifidobacterium animalis subsp. lactis (BB-12) in rats with systemic inflammatory response (SIR), which included diet-induced obesity and chemically induced colitis. Selective mKATP and sKATP blockers were used for assessment of their involvement in the mechanisms of probiotic preconditioning, while myocardial tolerance to ischemia–reperfusion injury was determined in the isolated perfused heart subjected to global ischemia–reperfusion. Intragastric administration of lyophilized LA-5 and BB-12 at a dose of 1.2 × 10⁸ CFU/mL for 7 days resulted in myocardial infarct size reduction. This cardioprotective effect was associated with specific changes in cytokine concentrations, namely, reduced levels of interleukin-1β, tumor necrosis factor-α, and interferon-γ. Moreover, probiotic therapy reversed SIR-induced reduction in the abundance of Lactobacillus spp. in the gut and SIR-induced elevation of acetic and propionic short-chain fatty acids in the blood. Preischemic pharmacological inhibition of sKATP channels but not mKATP channels abolished cardioprotective effect of probiotics. Therefore, it was suggested that sKATP channels are implicated in myocardial protection elicited by probiotics. Full article

Dehydroandrographolide (DA), a bioactive diterpenoid from Andrographis paniculata with diverse biological activity, was investigated for its antioxidant and anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages and dextran sulfate sodium (DSS)-induced murine colitis. In vitro, DA inhibited the inflammatory response by modulating extracellular Signal-Regulated Kinase (Erk), c-Jun N-terminal Kinase (Jnk), p38 Mitogen-Activated Protein Kinase (P38), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 activation, and downregulated interleukin-6 (il-6) and interleukin-1β (il-1β) mRNA. It also had antioxidant effects by upregulating Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2), NAD(P)H quinone dehydrogenase 1 (Nqo-1) and heme oxygenase-1 (Ho-1), promoting protein kinase B (Akt) and 5′-adenosine monophosphate-activated protein kinase-α1 (Ampk-α1) phosphorylation. DA decreased cyclooxygenase-2 (Cox-2) and inducible nitric oxide synthase (iNos) levels and alleviated intracellular reactive oxygen species (ROS) accumulation. In vivo, DA alleviated DSS-induced colitis in wild type (WT) mice by improving weight loss, disease activity index, colonic inflammation, and oxidative stress. The beneficial effects were linked to inhibiting Erk, Jnk, and P38 activation and enhancing Nrf2 signaling pathway. DA inhibited NOD-like receptor family pyrin domain-containing 3 (Nlrp3) inflammasome-mediated pryoptosis. However, DA’s protective effects were abolished in DSS-induced nrf2^−/− mice, suggesting its efficacy depends on Nrf2 signaling. Overall, DA alleviates oxidative stress, inflammatory responses, and pyroptosis in experimental colitis mice mainly by activating Nrf2 signaling pathway, highlighting its potential as a promising therapeutic option for inflammatory bowel disease. Full article

Streptococcus suis serotype 2 (SS2) is a major zoonotic pathogen causing infectious disease in various species, whose pathogenesis is still not well understood. The sodA gene is an important virulence gene of SS2 involved in the host’s immune response against pathogens. This study aimed to explore the impact of superoxide dismutase A (sodA) gene deletion on the pathogenicity of SS2 to mice. In this study, mice were grouped as control, WT, and ΔsodA, which were intraperitoneally injected with PBS, wild-type strain HA9801, and ΔsodA strain, respectively. WT proved to be a more virulent strain to mice with higher bacterial loads and survival rates in mice than those for ΔsodA. Moreover, more-severe tissue damage was observed in the lungs, liver, spleen, and kidneys of mice injected with WT than with ΔsodA. Additionally, macrophages accumulate to defend against SS2, and the results indicated that sodA gene deficiency decreased macrophage recruitment. In in vitro studies, caspase-1 and gasdermin D (GSDMD) were activated in macrophages induced by SS2; however, the absence of the sodA gene significantly inhibited the expression of pro-caspase-1, caspase-1, and GSDMD-N. Moreover, deletion of the sodA gene also decreased Interleukin-1 beta (IL-1β) and Interleukin-18 (IL-18) release in macrophages induced by SS2. Taken together, the absence of the sodA gene alleviated the pathogenicity of SS2 as a result of decreased macrophage accumulation and breakage of the caspase-1/GSDMD pathway in macrophages. Full article

Kidney diseases in patients with SLE include glomerulonephritis (GN), tubulointerstitial nephritis (TIN) and vasculitis alone or in combination. Immune complex (IC) deposition with complement activation in renal glomeruli causes lupus GN. However, IC deposition can also occur in the tubular basement membrane, renal interstitium, peritubular capillaries and arteries/arterioles to elicit inflammatory responses. TIN is usually associated with more severe GN with inflammation induced by IC. Immunopathologically, the aberrant presentation of T cell subpopulations, T_h1, T_h2, T_h9, T_h17, Treg and follicular T helper cells (T_fh), is closely implicated in TIN in SLE. In addition, M₁/M₂ macrophages and more specific dendritic cells (DCs) contribute to the inflammatory reactions of SLE-TIN. TIN may also present alone (isolated TIN) in apparently normal glomeruli or class I GN. It is intriguing that lupus nephritis constitutes two different pathological predilections, i.e., GN and tubulointerstitial inflammation. Alternatively, these two types may represent a continuous spectrum of inflammatory renal damages. In the present review, we will discuss in detail the pathology/immunopathogenesis, likely specific biomarkers/predictors and novel therapeutic designs for SLE-tubulointerstitial inflammation. In addition, we also raise several plausible investigation methods in SLE-tubulointerstitial inflammation that may help further elucidate this setting of perplexing renal diseases with rheumatic characteristics. Full article

Interleukin 17 (IL-17) is a crucial mediator at the interface of periodontal dysbiosis and host immunity. This review synthesizes current evidence on IL-17 in periodontitis (PD), its systemic connections, and the role of IL-17 gene variants. Clinical and experimental studies show that IL-17 rises in periodontal disease and is associated with the severity of PD via action on epithelial, stromal and osteoblastic cells to promote chemokine release, neutrophil recruitment, cyclooxygenase 2 and prostaglandin E2 synthesis, RANKL expression, osteoclastogenesis, and matrix metalloproteinase activity. Periodontopathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans pre-activate the local inflammation-maintaining Th17 response. There is converging evidence linking IL-17-centered signaling with rheumatoid arthritis, diabetes mellitus, and psoriasis in favor of a shared inflammatory network in barrier tissues and synovium. Despite these associations, IL-17 biology is contextually determined with mucosal defense and bone homeostatic roles that caution against unidimensional explanations. Evidence on IL-17A and IL-17F polymorphisms is still heterogeneous across populations with modest and variable risk associations with PD. Clinically, IL-17 in gingival crevicular fluid, saliva, or serum is a potential monitoring biomarker when utilized along with conventional indices. Therapeutically, periodontal therapy that reduces microbial burden may inhibit IL-17 function, and IL-17-targeted therapy has to balance potential benefit to inflammation and bone resorption against safety in oral tissues. The following research must utilize harmonized case definitions, standardized sampling, and multiethnic cohorts, and it must include multiomics to be able to differentiate between causal and compensatory IL-17 signals. Full article

Differentiation of oligodendrocytes and myelination are enhanced by interleukin-4, an anti-inflammatory cytokine secreted from immune cells or injured neurons, and peroxisome proliferator-activated receptor γ serves as a central effector. While intracellular zinc concentrations have recently been reported to change dynamically during oligodendrocyte development, the role of zinc in interleukin-4-enhanced oligodendrocyte differentiation has not been studied. Using primary oligodendroglial cells and the oligodendroglial CG4 cell line, we show that intracellular zinc concentrations transiently increased 1 day after interleukin-4-induced differentiation and that intracellular as well as extracellular zinc chelators repressed the interleukin-4-dependent effects. Our analyses furthermore reveal that STAT6 activated the zinc transporter ZIP11 downstream of interleukin-4 in a phosphorylation-dependent manner and that siRNA-dependent knockdown of ZIP11 abolished the interleukin-4-enhanced oligodendrocyte differentiation. An antagonist of peroxisome proliferator-activated receptor γ similarly repressed the interleukin-4-dependent differentiation. However, agonists did not affect intracellular zinc concentrations. These findings indicate that interleukin-4 upregulates ZIP11 expression via activation of STAT6 and facilitates extracellular zinc uptake, which in turn activates peroxisome proliferator-activated receptor γ and thereby promotes oligodendrocytes differentiation. Our results argue that a modulation of zinc concentrations may be beneficial for promoting oligodendrocyte differentiation and remyelination under demyelinating conditions such as multiple sclerosis. Full article

(1) Background: The assessment of neonatal health and prognosis is one of the most critical areas in pediatric medicine. Intrauterine inflammation and the fetal inflammatory response syndrome (FIRS) are increasingly recognized as major determinants of neonatal morbidity. Interleukin-6 (IL-6), measured in the umbilical cord (UC) blood, has emerged as a promising biomarker, reflecting both intrauterine conditions and early neonatal risk. This narrative review aims to synthesize current evidence on the predictive value of umbilical cord blood IL-6 for neonatal outcome, including sepsis, respiratory distress, hypoxic–ischemic encephalopathy (HIE) and mortality. (2) Methods: A comprehensive literature search was conducted in PubMed, Scopus, and Web of Science. Studies reporting umbilical cord IL-6 levels in relation to neonatal outcomes were analyzed and summarized narratively. (3) Results: Evidence consistently indicates that elevated umbilical cord IL-6 is associated with early-onset neonatal sepsis (EONS) and respiratory complications, and provides prognostic insight into neurological outcomes, even though results are influenced by gestational age (GA), mode of delivery, and the presence of chorioamnionitis. (4) Conclusions: UC IL-6 represents a valuable early biomarker for neonatal risk stratification and supports clinical decision-making. Future research should prioritize assay standardization, reference interval development, and prospective multicenter studies to validate its integration into routine neonatal care. Full article

Cluster of Differentiation (CD) 147, a transmembrane glycoprotein, plays a critical role in monocyte function by regulating invasion, migration and cytokine production. This study explored the impact of CD147 on monocyte chemotaxis and inflammatory responses following monocyte chemoattractant protein-1 (MCP-1) modulation using CD147 knockout (CD147^KO) THP-1 monocytes. CD147^KO THP-1 cells exhibited significantly enhanced migration towards MCP-1 and chemoattractants secreted by MDA-MB-231 breast cancer cells compared to wild-type (WT) THP-1 cells, while surface expression of the adhesion molecule CD44 remained unchanged. Despite their increased migration, CD147^KO cells showed no significant differences in CC chemokine receptor type 1 (CC1) or CC chemokine receptor type 2 (CCR2) protein expression. Upon MCP-1 stimulation, CD147^KO THP-1 monocytes exhibited elevated mRNA expression of interleukin (IL)-6 and IL-10, accompanied by a reduction in tumor necrosis factor alpha (TNF-α) at higher MCP-1 concentrations. IL-6 upregulation in CD147^KO THP-1 monocytes appears to be a candidate mediator of their enhanced migratory capacity. In summary, this study highlights the dual role of CD147 as a potential checkpoint in regulating THP-1 monocyte migration, with its function varying depending on the context and microenvironment. Additionally, CD147^KO THP-1 monocytes exhibited a shift in the balance between pro- and anti-inflammatory cytokine responses. Full article

Dental pulp tissue, enclosed within rigid dentin, is susceptible to bacterial invasion via dentinal tubules, often leading to severe pulpal inflammation. This condition is typically associated with a hypoxic microenvironment, yet the mechanistic link between hypoxia and inflammation remains unclear. We identified a marked upregulation of microRNA-210 (miR-210) in human dental pulp cells (hDPCs) cultured under hypoxic conditions. This study investigated the role of miR-210 in modulating inflammation in lipopolysaccharide (LPS)-stimulated hDPCs. Hypoxic conditions and enforced expression of hypoxia-inducible factor 1α (HIF1α) significantly increased miR-210 levels. While LPS stimulation elevated proinflammatory cytokines (Interleukin-6, Monocyte Chemoattractant Protein-1, and Tumor Necrosis Factor Alpha) and activated nuclear factor-kappa B (NF-κB) signaling, miR-210 overexpression suppressed LPS-mediated cytokine production and NF-κB activity. Luciferase assays revealed that miR-210 targets and negatively regulates TGF-beta activated kinase 1 binding protein 1 (TAB1), a key upstream regulator of NF-κB. Transfection with an miR-210 mimic reduced TAB1 expression, NF-κB activation, and cytokine output in both LPS-stimulated hDPCs and rat pulp tissue ex vivo. Conversely, miR-210 inhibition enhanced TAB1 levels and inflammatory cytokine expression under hypoxic conditions. These findings suggest that miR-210 mitigates inflammation via the TAB1–NF-κB pathway, functioning as a negative feedback regulator. miR-210 may represent a promising therapeutic target for pulpal inflammation. Full article

Background/Objectives: Hip osteoarthritis (HOA) is a progressive joint disease characterized by cartilage loss, subchondral bone changes, and synovial inflammation. While tumor necrosis factor receptor 1 (TNFR1), interleukin-6 (IL-6), and transforming growth factor-beta 1 (TGF-β1) are recognized as key mediators of joint pathology, their compartment-specific expression in the human hip synovium remains insufficiently characterized. Therefore, we aimed to investigate their localization and expression in the intimal and subintimal compartments of synovial tissue in patients with HOA compared to controls (CTRL). Methods: Synovial membrane samples were obtained from 19 patients with primary HOA undergoing total hip arthroplasty and 10 CTRL subjects undergoing arthroplasty for acute femoral neck fracture without HOA. Specimens were processed for hematoxylin and eosin (H&E) and immunofluorescence staining. Expression of TNFR1, IL-6, and TGF-β1 was quantified in the intima and subintima using ImageJ analysis. Group differences were assessed using two-way Analysis of variance (ANOVA) with Tukey’s test when assumptions were met; for heteroscedastic outcomes we applied Brown–Forsythe ANOVA with Dunnett’s T3 multiple comparisons. Results: Histological analysis confirmed synovitis in HOA samples, with intimal hyperplasia and mononuclear infiltration. IL-6 was significantly upregulated in the intima of HOA synovium compared with CTRLs, while subintimal expression remained unchanged. In contrast, TGF-β1 expression was reduced in the HOA intima, eliminating the normal intima–subintima gradient. For TNFR1, the within-HOA contrast (int > sub) was significant, whereas the intimal HOA vs. CTRL comparison showed a non-significant trend. Transcriptomic analysis supported IL-6 upregulation, while TNFR1 and TGF-β1 did not reach statistical significance at the mRNA level in an orthogonal, non-hip (knee-predominant) dataset. Conclusions: These findings demonstrate compartment-specific cytokine dysregulation in HOA, with increased intimal TNFR1 and IL-6 alongside reduced intimal TGF-β1. The synovial lining emerges as a dominant site of inflammatory signaling, underscoring its importance in disease progression. Full article

Skin aging is accelerated by both environmental factors—including ultraviolet (UV) radiation and pollution—and intrinsic processes such as chronic inflammaging. N-carbamylglutamate (NCG), an arginine precursor known for its benefits for gut and reproductive health, has not been extensively studied in dermatological applications. To explore its suitability as a multifunctional cosmetic ingredient, this study examines the protective role of NCG in counteracting UV-stimulated oxidative and inflammatory responses in skin cells. NCG significantly reduced UV-induced reactive oxygen species (ROS), indicating strong antioxidant properties. It also inhibited matrix metalloproteinase (MMP) activity, preserving collagen integrity and reducing wrinkle formation. In addition, NCG suppressed nitric oxide (NO) production and downregulated key inflammatory mediators—including cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6)—highlighting its anti-inflammatory potential. Furthermore, NCG reduced melanin production and the expression of melanogenesis-related factors such as the microphthalmia-associated transcription factor (MITF), tyrosinase-related protein 1 (TRP-1), and TRP-2. These findings support the role of NCG as a promising multifunctional cosmetic ingredient with antioxidant, anti-inflammatory, anti-wrinkle, and skin-brightening properties. Full article