Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie最新文献

Acanthamoeba keratitis (AK) is a painful corneal infection caused by pathogenic free-living amoebae of the genus Acanthamoeba, primarily affecting contact lens users with inadequate hygiene practices. Clinical manifestations include corneal infiltration, epithelial and stromal damage, and severe ocular pain, which may lead to vision loss or enucleation in advanced cases. Current treatments, such as polyhexamethylene biguanide (PHMB), often fail due to the parasite's ability to form drug-resistant cysts. In this study, metabolomic profiling revealed a significant accumulation of γ-aminobutyric acid (GABA) during encystation. Expression analysis of key genes associated with the GABA shunt pathway showed marked upregulation of glutamate dehydrogenase (GDH) and glutamate decarboxylase (GAD). Supplementation with exogenous GABA enhanced encystation rates and upregulated encystation-associated genes, including cellulose synthase I, autophagy-related protein 8, and encystation-mediating serine proteinase, suggesting that GABA may function as a signaling molecule regulating encystation. To explore potential anti-encystation strategies, β-lactam antibiotics, well-known GABA_A receptor antagonists, were tested. Cefotaxime, carbenicillin, and penicillin G significantly inhibited cyst formation without inducing cytotoxicity, whereas non-β-lactam antibiotics showed no such effect. These findings suggest that the inhibitory effect is associated with the β-lactam ring structure and may involve interference with GABA-mediated signaling pathways. Collectively, our study reveals a critical role of GABA metabolism in Acanthamoeba encystation and highlights β-lactam antibiotics as potential adjunctive agents for overcoming cyst-associated drug resistance in AK treatment.

It is becoming more widely acknowledged that obesity is a chronic low-grade inflammatory disease that has a significant influence on brain health in addition to metabolic problems. Adipose tissue growth, macrophage polarization, and cytokine release all contribute to systemic inflammation, which weakens the blood-brain barrier (BBB) and promotes immune-to-brain communication. Saturated fatty acids and gut-derived lipopolysaccharides activate Toll-like receptor 4 (TLR4) in the central nervous system, which triggers downstream nuclear factor-κB (NF-κB) and Mitogen-activated protein kinase (MAPK) cascades and increases neuroinflammation. At the same time, mitochondrial malfunction and oxidative stress hasten the buildup of reactive oxygen species (ROS), which further primes the NOD-like receptor family, pyrin domain-containing 3 (NLRP3) inflammasome and maintains glial hyperactivation. These processes work together to cause synaptic dysfunction, insulin resistance in neurons, and heightened susceptibility to neurodegenerative illnesses, including Parkinson's and Alzheimer's. Pharmacological inhibitors, natural substances, and lifestyle changes that target TLR4, MAPK signaling, and ROS-mediated pathways have the potential to disrupt this metabolic-inflammatory-neuronal axis. Developing comprehensive solutions to reduce obesity-driven neuroinflammation requires an understanding of the molecular interactions between peripheral metabolic stress and central immune activation.

Rheumatoid arthritis (RA) encapsulates chronic autoimmune pathology, characterised by dysregulated immune responses that drive progressive joint destruction and systemic complications. Central to this process is aberrant osteoclast activation driven by RANKL-RANK signalling, which drives excessive bone resorption. In this context, we evaluated UA-1, an indole derivative of ursolic acid. Ursolic acid is a phytochemical known for its anti-arthritic properties with limited clinical applicability (BCS class IV), which drives the need for derivatization. In our recent study, UA-1 showed improved anti-inflammatory potential in comparison to ursolic acid, which may be attributed to its improved physicochemical properties. These results prompted us to evaluate UA-1's anti-arthritic potential both in vitro using RANKL-stimulated osteoclastogenesis in RAW 264.7 macrophages and in vivo using the CIA model. UA-1 significantly reduced the levels of pro-osteoclastogenic cytokines, thereby alleviating subsequent downstream osteoclast differentiation, as corroborated by the decreased expression of osteoclast-specific markers (TRAP, CTSK, MMPs). It also modulated key signalling pathways, including NF-κB, MAPK, and JAK/STAT. Additionally, UA-1 inhibited the key adaptor protein TRAF6 and downregulated the NFATc1/c-Fos axis, major transcription factors involved in osteoclastogenesis. Furthermore, UA-1 also enhanced the antioxidant levels by modulating the NRF-2-mediated antioxidant pathway. Additionally, in the CIA model using C57BL/6, UA-1 alleviated disease markers and reduced pro-inflammatory cytokines, while minimizing joint damage as evidenced by H&E and picrosirius red staining. Overall, the results suggest the potential efficacy of UA-1 in managing RA, given its pronounced suppression of inflammation, oxidative stress and osteoclastogenesis.

Microglia cells are the initial immune cells regulating neuroinflammation response. Under neuro-degenerative conditions, microglia exhibit as an over-activated phenotype, which generate large amounts of cytokines and inflammatory mediators. Euonymus hamiltonianus Wall. (E. hamiltonianus) showed an effect of enhanced memory and cognitive abilities in Alzheimer Disease (AD) model in our previous research. However, it is remained unknown about the anti-inflammation effect of E. hamiltonianus behind the neurodegenerative situation. The aims of the research are clarifying the possible therapeutic effects and its active compound of E. hamiltonianus on neuro-inflammation on the central nervous system. By the activity guided isolation, dihydrotricetin (compound 1) was identified as an active compound with BV-2 microglia and NMR Spectroscopy. In BV-2 LPS-induced microglial cells, compound 1 inhibited the pro-inflammatory factors, including Prostaglandin E2 (PGE2), interleukin (IL)-6, tumor necrosis factor (TNF)-α, and nitrite oxide (NO) production. This suppressed the activation of microglia in LPS-injected mouse cortex. Besides, the research indicated that compound 1 inhibited PI3K/AKT/IκB/NF-κB and MAPK pathways, and further promoted the inhibition of NLRP3 signaling activation. This research determined that compound 1 is involved in the NRF2/HO-1 signaling and anti-oxidative activity. These data suggest that compound 1 can be a key regulator of microglial activation in LPS-induced neuro-inflammation in vivo and in vitro.

This study aimed to isolate bioactive constituents from Ardisia gigantifolia and assess their effects on gastric cancer stem cells (CSCs) properties. Cytotoxicity and proliferation were quantified using the MTT assay; cell-cycle distribution, CD44 expression, and apoptosis/senescence markers were evaluated by flow cytometry and β-galactosidase staining; reactive oxygen species (ROS) generation and tumorsphere formation were analyzed by fluorescence microscopy and 3D culture; gene expression was measured by qPCR; molecular docking probed interactions with CSCs markers and Notch signaling proteins. Four compounds were isolated, including Ardisiaoside A, β-sitosterol, and two long-chain n-alcohols (octacosan-1-ol, nonacosan-1-ol). Ardisiaoside A was reported from this species for the first time and showed the greatest potency, reducing viability at low micromolar doses (IC₅₀: 1.08 ± 0.37 µM in AGS, 2.50 ± 0.72 µM in MKN45 cells). It suppressed migration, induced G2/M arrest, and triggered senescence. CD44 surface levels was markedly reduced, and tumorsphere number and size were inhibited at 2.5 µM. qPCR and immunofluorescence demonstrated notable downregulation of stemness-related genes (OCT4, NANOG) and Notch pathway components, consistent with reduced self-renewal. Molecular docking supported the binding of Ardisiaoside A to NANOG, OCT4, CD44, and Notch proteins (NOTCH1, HES1, DLL1, DLL4), consistent with target inhibition. In conclusion, Ardisiaoside A, a newly identified triterpenoid glycoside from Ardisia gigantifolia, represents a promising candidate that inhibits cell proliferation by reducing cancer stem-cell populations and inducing cellular senescence in gastric cancer.

Prostate-specific membrane antigen (PSMA) is a key target for radioligand therapy (RLT) in prostate cancer (PCa). However, its subcellular localization is critical, as ligand uptake via PSMA mediated endocytosis influences therapeutic efficacy. This study examines the impact of androgen receptor blockade (ARB) on PSMA membrane trafficking and its modulation by endoplasmic reticulum (ER) stress in PCa cell-lines and tissue samples from ARB pretreated patients. LNCaP and VCaP cells were treated with enzalutamide (0.1-10 µM) for 1-7 days. PSMA localization was assessed via optical sectioning, fluorescence profiling, membrane protein isolation, and Western blotting. ER stress markers BiP and PERK were quantified. To evaluate PSMA targeting and therapeutic response, cellular uptake of [¹ ⁷⁷Lu]Lu-PSMA-Imaging and Therapy (I&T) was quantified via gamma counting, while treatment efficacy was assessed through MTS and Live/Dead-staining. ARB significantly increased PSMA membrane localization, with a maximal effect at 1 µM (7 days) or 10 µM (4 days). Optimized conditions led to a fourfold increase in PSMA uptake in LNCaP and a twofold increase in VCaP. However, prolonged or high dose ARB induced ER stress, evidenced by BiP/PERK upregulation, correlating with reduced PSMA trafficking in vitro and in vivo and diminished [¹⁷⁷Lu]Lu-PSMA-I&T uptake in vitro. Optimized ARB-RLT combinations significantly enhanced therapeutic efficacy. These findings highlight ARB's potential to enhance RLT-efficiency by optimizing PSMA membrane localization. Crucially, ER stress markers correlated with PSMA trafficking, suggesting serum-based profiling could enable individualized ARB adjustments. Future studies should validate these biomarkers to establish personalized ARB-RLT strategies for improved clinical outcomes.

In this study, we developed a streamlined in vitro platform to assess the systemic toxicity of multidrug combinations within a clinically relevant timeframe, facilitating its application in personalized medicine. By incorporating cellular models that represent major toxicity-sensitive organs, such as the kidney, liver, and heart, we evaluated two previously optimized multidrug combinations (C2 and REMP). Our findings revealed distinct organ-specific toxicity profiles, with some drug-induced toxicities exacerbated upon combination. To evaluate the influence of model complexity, we compared responses between simple proliferative cell lines and more advanced models. Proliferative cell models, while useful for initial toxicity screenings, frequently failed to predict the severity of drug-induced toxicity. For instance, the C2 combination decreased cell viability by 50 % in patient-derived kidney organoids but only by 20 % in HEK293T cells. However, the C2 combination caused a 77 % viability reduction in differentiated hepatocyte spheroids, 32 % more than its effect on non-differentiated hepatocyte-like cells. C2 showed significant release of lactate dehydrogenase compared to 0.1 % DMSO. These findings underscore the critical need for systemic and biologically relevant drug safety assessments in the development of novel drug combinations, regardless of known single-drug safety. Despite some limitations, the platform accurately reproduced known single-drug toxicity profiles, confirming its translational potential. Overall, this biologically relevant approach enables efficient early-stage toxicity screening of drug combinations, supporting a safer development of personalized cancer therapy.

Oxytocin (OT) is a neurohypophyseal peptide with decreased expression during aging, essential for skeletal muscle homeostasis, and counteracts sarcopenia in aged mice. Yet, its function in cancer cachexia remains unexplored. We investigated OT serum levels in cancer patients, comparing these with cachectic patients and non-cancer controls, as well as OT/OT-receptor (OTR) mRNA in sarcopenic muscle. Potential benefits of OT were assessed in vitro using L6C5 myoblasts and murine isolated myofibers exposed to C26-conditioned medium and in vivo using the C26/Balb/c cancer cachexia model. Finally, the molecular effects of OT on de novo protein synthesis via bio-orthogonal non-canonical amino acid tagging (BONCAT) were investigated using MetRS^L274G C57BL/6 mice. Circulating OT was significantly lower in cancer patients than in non-cancer disease (-60 %, p < 0.01). Sarcopenic muscle showed over threefold downregulation of the OTR (p < 0.032). In vitro, OT reversed the myogenic inhibition induced by tumor cell-conditioned medium, boosting fusion index (>6-fold, p < 0.001), nuclei per myotube (>8-fold, p < 0.001), and myotube diameter (>6-fold, p < 0.001). In C26 tumor-bearing mice, OT restored skeletal muscle mass (>1.5-fold, p < 0.001), fiber cross-sectional area (>1.5-fold, p < 0.001), and overall body weight, while reducing the muscle degradation determinants: MuRF1 (>8-fold, p < 0.001) and Atrogin1 (>6-fold, p < 0.001). Metabolic proteomics showed that cancer perturbed and OT restored the synthesis of key proteins (+23 %, p < 0.05) that play essential roles in muscle regeneration and inter-organ communication. Given that OT is approved for clinical use, our findings suggest that it could quickly be translated into effective therapies for preventing or treating cachexia in cancer patients.