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Toxoplasma gondii, an obligate intracellular protozoan infecting approximately one-third of the global population, poses a significant yet underappreciated threat to reproductive health in both sexes. Although this parasite has long been linked to birth defects caused by infection during pregnancy, new research shows that it also reduces fertility in both sexes through different but related mechanisms. This review synthesizes knowledge on T. gondii-induced reproductive pathology across females and males, examining shared mechanistic themes while respecting tissue-specific differences, and evaluates emerging therapeutic strategies. In females, the parasite establishes persistent uterine reservoirs, triggers decidual immune dysregulation characterized by NK cell cytotoxicity, M1 macrophage polarization, Treg apoptosis, and inflammasome-mediated pyroptosis, while disrupting estrogen and progesterone signaling through both host receptor modulation and intrinsic parasite steroidogenic enzymes (TgCYP450mt, TgMAPR, Tg-HSD). In males, T. gondii breaches the blood–testis barrier, induces germ cell and Leydig cell apoptosis via ER stress and caspase pathways, impairs sperm quality parameters across acute and chronic infection, and disrupts the hypothalamic–pituitary–gonadal axis. Conserved molecular mechanisms—including NLRP3 inflammasome activation, PERK/eIF2α/ATF4/CHOP-mediated ER stress, and oxidative stress—operate in both reproductive tissues. The parasite’s intrinsic steroidogenic capability and bidirectional hormonal manipulation represent a paradigm shift in understanding host–parasite interactions. Conventional antiparasitics face limitations due to poor reproductive sanctuary penetration. Immunomodulatory approaches targeting Trem2, Tim-3, and the NLRP3 inflammasome show promise, along with natural products including Inonotus obliquus polysaccharide and ginseng polysaccharide. Nanomedicine platforms and mRNA vaccine candidates offer new directions for overcoming tissue barrier limitations. Toxoplasma gondii represents a fundamental threat to fertility and pregnancy outcomes rather than merely a risk for congenital infection. Integrated therapeutic strategies addressing direct parasitism, immunopathology, and endocrine disruption are needed. Longitudinal cohort studies, strain-specific mechanistic comparisons, and clinical trials of immunomodulatory adjuncts are urgently required. Full article

Adipogenesis is a critical factor in causing obesity, which is a global health problem associated with metabolic disorders, such as insulin resistance and cardiovascular diseases. Natural compounds with anti-adipogenic activity may represent potential approaches for modulating adipocyte function. However, despite increasing interest in natural products, the anti-adipogenic potential of acridone alkaloids, particularly prenylated derivatives, remains largely unexplored. This study examined the effects of N-methylatalaphylline (NMA), a prenylated acridone alkaloid, on adipocyte differentiation, lipid accumulation, and glucose uptake. NMA exhibited anti-adipogenesis, particularly toward preadipocytes, and significantly reduced lipid accumulation in murine 3T3-L1 and human PCS-210-010 adipocytes at nontoxic doses (1.5–6 µM). At 3–6 µM, NMA downregulated adipogenic regulators, including PPARγ, C/EBPα, and SREBP1, along with adipogenic effectors, such as FABP4, adiponectin, LPL, PLIN1, and FAS. Mechanistic studies indicated that NMA treatment was associated with reduced phosphorylation of AKT, ERK, and p38, accompanied by cell-cycle arrest and inhibition of mitotic clonal expansion. Meanwhile, activation of AMPK-ACC signaling, which may contribute to suppression of adipogenesis and reduced glucose uptake, was observed in differentiated 3T3-L1 cells after treatment with 6 µM NMA for 48 h. Additionally, molecular docking and molecular dynamics simulations suggested potential interaction between NMA and ERK1, supported by hydrogen bonding and hydrophobic contacts. Overall, these findings suggest that NMA exerts anti-adipogenic effects in vitro by modulating adipocyte proliferation, differentiation, and lipid metabolism. These findings highlight NMA as a promising acridone alkaloid scaffold for anti-adiposity applications, warranting further in vivo validation. Full article

Background: Hepatic ischemia–reperfusion injury (IRI) remains a major challenge in liver transplantation (LTx) and hepatectomy. Previous studies identified a 12/15-lipoxygenase (12/15-LOX)-driven lipid peroxidation cascade promoting cell death, whereas glutathione peroxidase 4 (GPx4)-dependent metabolism acts antagonistically. This study investigated whether tacrolimus protects against hepatic IRI through this redox axis. Methods: Male C57BL/6 mice underwent 65% partial hepatic warm ischemia and reperfusion with or without tacrolimus preconditioning. Liver tissue and serum were analyzed by spectral photometry, Western blotting, TUNEL assay, and serum enzyme measurement. Results were statistically analyzed and compared with previously published results of 12/15-LOX inhibition by baicalein pretreatment and its carrier DMSO. Also, the combination of both tacrolimus and baicalein was investigated. Results: Tacrolimus increased the oxidative glutathione activity quotient (GSSG/GSH) by 75.1% (p = 0.0302), attenuated MAPK signaling, reduced SAPK/JNK by 84.6% (p = 0.0059), with ERK1/2 showing a downward trend, decreased Caspase-3 activation by 66.9% (p < 0.001) and PARP cleavage by 59.9% (p = 0.0330), and lowered TUNEL-positive cell death by 61.8% (p = 0.0015). Tacrolimus achieved hepatoprotection comparable to 12/15-LOX inhibition, but without hepatotoxicity, whereas combined treatment conferred no additional benefit yet bore toxic properties. Conclusions: Tacrolimus preconditioning mitigates hepatic IRI through a glutathione-linked redox–signaling–cell death axis and exerts cytoprotective effects beyond immunosuppression. Full article

Neurotensin (NTS) binds to the G protein-coupled receptors (GPCRs) NTSR1 and NTSR2. NTSR1 regulates transactivation of the EGFR, HER2, and HER3, but its effects on HER4 are unknown. By Western blot, NTSR1 and HER4 were present in six lung cancer cell lines examined. In NCI-H522 or NCI-H661 cells, adding NTS increased phosphorylation (P) of tyrosine (Y) 1284 on HER4. Because SR48692 antagonized NTS’s ability to increase P-HER4 or P-ERK, NTSR1 may play an important role in NSCLC. SR48692, HER4 siRNA, reactive oxygen species inhibitors, and the tyrosine kinase inhibitor ibrutinib inhibited NTS-induced P-HER4. Adding NTS to NCI-H661 cells increased the formation of HER4/HER4, HER4/ EGFR, and HER4/HER2 dimers. Adding NTS to NSCLC cells increased both P-ERK and P-AKT, which were inhibited by PD98059 and LY294002, respectively. The growth of NCI-H522 or NCI-H661 cells was stimulated by NTS or neuregulin 1 (NRG1), a HER4 ligand, but inhibited by SR48692 or ibrutinib. The results indicate that NTSR1 regulates HER4 transactivation, thereby increasing the proliferation of lung cancer cells. Full article

Background/Objectives: Chronic glomerulonephritis (CGN) is a progressive chronic kidney disease that can ultimately advance to end-stage renal disease (ESRD). Zhuangyang Bushen Pill (ZYBSW) is a traditional Chinese herbal formulation derived from the Yi ethnic medicine of Yunnan Province, and it has been widely employed in folk practice for the amelioration of chronic nephritis and renal dysfunction. This study was designed to evaluate the therapeutic efficacy of ZYBSW against CGN and to provide preliminary insights into its underlying mechanisms of action. Methods: The nephropathy model was induced in mice by tail vein injection of ADR (10 mg/kg). Renal function was evaluated by measuring relevant biochemical parameters, and renal histopathological alterations were examined using HE staining. Chemical constituents of ZYBSW were analyzed by LC-MS/MS. Its mechanisms of action were investigated using network pharmacology, WGCNA, molecular docking, multiplex immunofluorescence, and Western blotting. Results: ZYBSW significantly reduced ACR by 88.9%, SCr by 56.4%, and BUN by 30.4%, increased ALB by 32.4%, and alleviated renal histopathological damage (all p < 0.01). LC-MS/MS analysis identified 419 chemical constituents in ZYBSW. Network pharmacology, WGCNA, and molecular docking experiments identified EGFR and DUSP1 as potential targets, and indicated the MAPK pathway as a key pathway. Mechanistic studies revealed that ZYBSW significantly inhibited EGFR expression in renal tissue, enhanced DUSP1 expression, and reduced the phosphorylation levels of ERK, JNK, and p38. Conclusions: This study reveals ZYBSW can effectively alleviate CGN, with EGFR and DUSP1 as likely therapeutic targets, and its mechanism of action primarily involves regulating the MAPK signaling pathway. Full article

Introduction: Gastric cancer is a prevalent and aggressive malignancy driven by complex signaling networks. Estrogen receptor-α36 (ER-α36), a membrane-localized receptor, mediates non-genomic signaling and promotes tumor progression. ER-α36 can interact with epidermal growth factor receptor (EGFR) to activate downstream mitogen-activated protein kinase (MAPK) signaling, but the detailed mechanism in gastric cancer remains unclear. This study aimed to explore whether ER-α36 promotes gastric cancer progression by regulating serum and glucocorticoid-regulated kinase 1 (SGK1)-mediated Erk1/2 activation. Methods: We collected 53 human gastric adenocarcinoma specimens and detected ER-α36 expression by immunohistochemistry. Bioinformatics analysis was used to identify ER-α36-related kinases. Gastric cancer cell lines (SGC7901, HGC27, NCI-N87, and MFC) were used for in vitro studies. Western blotting, qRT-PCR, immunofluorescence, co-immunoprecipitation (Co-IP), wound healing, MTT, and Transwell invasion analyses, and nude mouse orthotopic tumor models were applied to investigate the function and mechanism of the ER-α36/SGK1/Erk1/2 axis. Results: ER-α36 was positively expressed in 62.3% of gastric adenocarcinoma tissues and was associated with poor differentiation and prognosis. SGK1 was identified as a key kinase downstream of ER-α36. ER-α36, SGK1, and p-Erk1/2 were co-upregulated in gastric cancer tissues and cells. ER-α36 regulated Raf/MEK1/2/Erk1/2 phosphorylation in an SGK1-dependent manner. EGF-induced Erk1/2 activation required both ER-α36 and SGK1. Overexpression of ER-α36 promoted the proliferation, migration, and invasion of gastric cancer cells, while SGK1 knockdown abolished these oncogenic effects. In vivo experiments confirmed that ER-α36 promoted gastric tumor growth and EGFR/Erk signaling, which was attenuated by SGK1 knockdown. Conclusions: ER-α36 contributes to the malignant progression of gastric adenocarcinoma by activating the Erk1/2 pathway through SGK1. The ER-α36–SGK1–Erk1/2 axis may serve as a novel therapeutic target for gastric cancer. Full article

Hepatocellular carcinoma (HCC) is a highly aggressive malignancy with a poor prognosis. While sorafenib serves as the first-line therapy for advanced HCC, its efficacy is frequently hampered by side effects and the development of drug resistance, necessitating the development of novel agents to enhance HCC sensitivity to sorafenib. In this study, we demonstrate that the antihistamine astemizole significantly enhanced the antitumor efficacy of sorafenib in HCC cell lines. This combination treatment cooperatively inhibited HCC cells’ proliferation and induced cell cycle arrest at the G1 phase, as evidenced by decreased cyclin D1 and p-Rb levels and increased p27 expression. Furthermore, the combination of astemizole and sorafenib synergistically inhibited HCC cells’ migration, invasion, and adhesion. It also reduced F-actin polymerization and the expression of metastasis-regulating proteins, including p-Integrinβ1, FAK, and MMP1. Additionally, the combination treatment suppressed tube formation in HUVECs, accompanied by downregulation of HIF-1α and reduced VEGF secretion. Co-inhibition of Eag1 and the ERK/MAPK signaling pathway may underlie the enhanced anti-HCC effects of sorafenib by astemizole. Collectively, these findings indicate that astemizole significantly enhanced the antitumor activity of sorafenib by inhibiting proliferation, metastasis, and angiogenesis in HCC cells, suggesting its potential as a promising adjuvant to improve sorafenib-based therapy in HCC. Full article

Acinetobacter baumannii, a prominent opportunistic pathogen in healthcare settings, causes severe infections and poses significant challenges for clinical treatment. This study investigates the synergistic effects of α-pinene combined with meropenem (MEM) on A. baumannii biofilm formation and lung injury in mice, aiming to develop new strategies to combat persistent infections and antibiotic resistance. α-pinene combined with MEM exhibited strong synergistic antibacterial activity against carbapenem-resistant A. baumannii (CRAB 5E9). The combination significantly inhibited biofilm formation, extracellular polymer production, surface motility, and quorum sensing. The expression of key genes such as ompA, bfmR, bap, csuAB, abaI, and abaR was reduced by up to 61%. In vivo, the treatment alleviated weight loss, decreased the bacterial load in lung tissue, and reduced lung inflammation. Furthermore, it significantly suppressed proteins involved in the inflammatory response and the MAPK pathway, including TLR4, NF-κB, NLRP3, TRAF6, ERK2, p38 MAPK, JNK, and TNF-α. The combination of α-pinene and MEM synergistically inhibits A. baumannii biofilm formation and alleviates the inflammatory response in a mouse model, offering a potential therapeutic approach for combating A. baumannii infections. Full article

This study concurrently addressed the separation method for carbon dots derived from Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (GRRPM) and the in vitro evaluation of their anti-allergic biological activity. Glycyrrhizae Radix et Rhizoma Praeparata cum Melle Carbon Dots (GRRPM-CDs) were prepared via decoction followed by dialysis, and their properties were characterized using High-Performance Liquid Chromatography (HPLC) and nanomaterial techniques. Anti-allergic activity was evaluated using a C48/80-induced RBL-2H3 mast cell degranulation model. Safety and efficacy were assessed using the CCK-8 assay, direct intervention, and drug-containing serum methods. The release of β-hexosaminidase (β-hex), histamine (HIS), interleukin-4 (IL-4), and tumor necrosis factor-α (TNF-α) was measured by ELISA, and key proteins in the MAPK signaling pathway were analyzed by Western blot. GRRPM-CDs inhibited mast cell degranulation and the release of allergic and inflammatory mediators in a dose-dependent manner. They also significantly downregulated the phosphorylation levels of the JNK, ERK, and p38 proteins in the MAPK signaling pathway. GRRPM-CDs exhibit significant anti-allergic activity, likely via suppression of the MAPK pathway. These findings provide new insights into the bioactive components of processed Glycyrrhiza and suggest potential avenues for developing novel therapies for allergic diseases. Full article

Endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) represent fundamental cellular adaptive mechanisms that maintain protein homeostasis and metabolic balance. Many RNA viruses, particularly flaviviruses such as dengue virus (DENV), Zika virus (ZIKV), West Nile virus (WNV), yellow fever virus (YFV), and Japanese encephalitis virus (JEV), extensively remodel the ER to establish replication compartments and assemble progeny virions. This massive reorganization disrupts ER homeostasis, leading to UPR activation. Emerging evidence reveals that flaviviruses not only trigger but also manipulate the three UPR branches—PERK, IRE1, and ATF6—to optimize viral translation, replication, and egress. In parallel, flavivirus infection profoundly alters host lipid metabolism and promotes dynamic changes in lipid droplets (LDs), key organelles that mediate lipid storage and serve as scaffolds for viral replication and assembly. The UPR intimately connects to LD biogenesis through transcriptional and translational programs mediated by XBP1, ATF4, and ATF6, thereby coupling ER stress responses to lipid remodeling and energy homeostasis. This intricate crosstalk between UPR and LDs creates a metabolic and structural niche favorable for viral replication but detrimental to host cell integrity. This review provides a comprehensive analysis of the molecular mechanisms by which flaviviruses exploit ER stress and the UPR to reprogram lipid metabolism and LD dynamics. We highlight the dual role of UPR signaling in promoting adaptive lipid synthesis and initiating cell death under prolonged stress, discuss recent insights into ER–LD interactions during flavivirus infection, and explore therapeutic opportunities targeting UPR–lipid metabolic pathways as broad-spectrum antiviral strategies. Understanding this interconnected network will advance our knowledge of viral pathogenesis and identify new avenues for host-directed antiviral intervention. Full article

Down syndrome (DS), caused by trisomy 21, is the most prevalent genetic condition associated with accelerated aging and near-universal development of early-onset Alzheimer’s disease (AD). Beyond gene-dosage imbalance, trisomy 21 induces widespread transcriptional, metabolic, and proteomic remodeling that establishes a chronic state of proteotoxic and oxidative stress from early development. Increasing evidence identifies DS as a disorder of proteostasis network failure, in which sustained translational pressure, redox disequilibrium, and degradation pathway insufficiency progressively erode cellular resilience. In the DS brain, persistent endoplasmic reticulum stress with PERK-dominant signaling, mitochondrial dysfunction characterized by oxidative phosphorylation deficits and excessive reactive oxygen species production, and impaired antioxidant responses create a highly vulnerable intracellular environment. Concomitantly, degradation systems become compromised: proteasomal catalytic activity declines, ubiquitin-dependent signaling is remodeled, and chronic mTOR hyperactivation suppresses autophagic and mitophagic flux. The coordinated impairment of the ubiquitin–proteasome system and autophagy establish a feed-forward cycle of proteotoxic accumulation and redox amplification. Within this framework, Alzheimer-like neuropathology in DS emerges not solely from amyloid precursor protein triplication but as the late manifestation of decades-long proteostasis exhaustion. Therapeutic strategies aimed at restoring global proteostasis and redox balance may therefore represent a more effective systems-level approach to mitigating neurodegeneration in DS. Full article

Cigarette smoke (CS) is the primary risk factor for the development of chronic obstructive pulmonary disease (COPD). Investigating the impact of CS on human airway epithelium is important for understanding COPD development and combating its effects. While some studies show that long exposure to CS activates inflammasome formation in airway epithelium, leading to cytokines’ maturation and release, its acute effect on inflammation regulation requires further elucidation. Due to the importance of acute cellular responses in modulating cell survival and controlling inflammatory outcomes, we examined the effect of acute cigarette smoke extract exposure on human bronchial epithelial cells. Due to the high reactive oxygen species content in CS, we hypothesize that acute CS exposure activates the integrated stress response (ISR) pathway leading to stress granules (SG) formation to facilitate oxidative stress resolution and promote cell survival. Immunostaining, fluorescence confocal imaging, quantitative analyses, and immunoblotting were performed to test our hypothesis. We report here that acute exposure to CS extract triggers canonical SG formation by activating the ISR pathway via the PERK/eIF2α arm in a reactive oxygen species-dependent manner. SG formation is abolished upon inhibiting PERK or eIF2α function, or by scavenging oxidants prior to smoke exposure. Characterizing SG formation in terms of measuring SG size and abundance and the sequestration of the SG marker G3BP1 reveals that SG formation is maximal at 15% CS extract exposure for 2 h and undergoes gradual disassembly at longer exposure times. This is closely dependent on cytoplasmic p-eIF2α levels. These results demonstrate that acute exposure to CS activates the protective ISR pathway to potentially reduce the detrimental effects of CS and promote stress resolution and cell survival. Full article

Periplaneta americana extract can promote wound healing and may play an important role in skin wound healing. In this study, we identified a peptide (DL-13) from Periplaneta americana L. and explored its role and mechanisms in skin wound healing. In vitro, the effects of DL-13 on proliferation, migration, and related gene/protein expression in HaCaT keratinocytes were assessed via qRT-PCR and Western blot. In vivo, rat wound healing assays confirmed its efficacy. Results showed DL-13 accelerated rat wound healing. In in vitro studies, DL-13 activated EGFR and its downstream PI3K/AKT/mTOR, ERK/MAPK, and JAK2/STAT3 pathways, upregulated EMT-related proteins (N-cadherin, MMP-2, p-FAK, β-catenin), partially regulated macrophage cytokine secretion, and promoted HaCaT proliferation/migration, thereby facilitating re-epithelialization at skin injury sites. Overall, DL-13 may enhance the function of HaCaT cells by activating the EGFR signaling pathway and regulate inflammatory factors in macrophages, thereby promoting the healing of skin wounds in rats. The results of this study will lay an experimental and scientific foundation for the discovery of new compounds for wound healing and their application. Full article

Excessive osteoclast activity drives inflammatory bone loss in osteoporosis, rheumatoid arthritis, and periodontitis. Natural compounds represent promising therapeutic candidates with favorable safety profiles; however, few exhibit pathway-biased mechanisms of action. Here, we report that angelic acid (AA), a naturally occurring unsaturated monocarboxylic acid, potently inhibits RANKL-induced osteoclastogenesis. This effect occurs with an IC₅₀ of 1.9 µM without cytotoxicity. Mechanistically, AA selectively suppressed RANKL-activated phosphorylation of ERK1/2, p38, and JNK (all three MAPK branches), while leaving NF-κB transcriptional activity unaffected. This preferential MAPK suppression disrupted downstream NFATc1 nuclear translocation, thereby preventing NFATc1-driven transcription of osteoclast-specific effector genes including TRAP, cathepsin K, and Atp6v0d2. These findings identify AA as a novel inhibitor of the RANKL–MAPK–NFATc1 axis, providing a mechanistic foundation for its therapeutic development in osteoporosis and other osteolytic diseases. Full article

Background/Objectives: Saikosaponin D (SSD) is a bioactive compound from traditional Chinese herbs with known anti-tumor activities, including apoptosis induction, autophagy modulation, and inhibition of cell migration and invasion. However, the mechanisms underlying its effects on human endometrial cancer Ishikawa cells remain elusive. This study aimed to investigate the anti-tumor effects of SSD on EC Ishikawa cells and elucidate the molecular pathways involved, focusing on DNA damage, cell cycle regulation, autophagy, endoplasmic reticulum (ER) stress, and AMPK signaling. Methods: We performed in vitro experiments using Ishikawa cells and in vivo studies using a female BALB/c nude mouse xenograft model. DNA damage was assessed via comet assay, intracellular Ca²⁺ concentration via Fluo-3 AM staining, autophagy via transmission electron microscopy, and apoptosis via flow cytometry. Autophagy was inhibited using 3-methyladenine, and ER stress was modulated with the PERK inhibitor GSK2656157. Protein expression levels of related genes were analyzed by western blotting. No preregistration number or CONSORT details applied, as this was a pre-clinical study. Results: SSD treatment was associated with DNA damage and G2/M phase cell cycle arrest in Ishikawa cells both in vitro and in vivo. SSD was associated with an increased LC3II/LC3I ratio and activation of the AMPK pathway. It was also associated with ER stress, as evidenced by downregulation of PERK, mTOR, and eIF2α, and upregulation of p-eIF2α. Furthermore, SSD was associated with modulation of the AMPK signaling pathway to inhibit cell migration and invasion. Conclusions: SSD exerts anti-tumor effects on human EC Ishikawa cells in vitro and in vivo through mechanisms involving DNA damage, G2/M arrest, autophagy, ER stress, and AMPK-mediated inhibition of migration and invasion. These findings suggest that SSD may represent a potential therapeutic agent for EC. Full article