Opioids Promote Autophagy and Attenuate LPS-Induced Cellular Senescence-Associated Changes in Microglia

Resveratrol attenuates LPS-induced oxidative stress and apoptosis in HMC3 microglial cells, partly involving NRF2-related signaling.

Postoperative cognitive dysfunction (POCD) is associated with neuroinflammation and oxidative stress, but the underlying mechanisms remain unclear. Resveratrol (RES), a natural polyphenol, has shown neuroprotective potential; however, its effects on microglial injury related to postoperative neuroinflammation have not been fully characterized. In this study, potential shared targets of RES and POCD were first explored using network pharmacology, followed by experimental validation using an LPS-stimulated HMC3 microglial cell model. HMC3 cells were treated with LPS (1000 ng/mL) and RES (50 µM), either with or without the NRF2 inhibitor ML385 (1 µM). Cell viability, proliferation, apoptosis, ROS production, and NRF2-related markers were assessed using CCK-8, EdU staining, flow cytometry, qPCR, Western blotting, and immunofluorescence. Network pharmacology suggested that apoptosis- and NRF2-related antioxidant pathways may be involved in the effects of RES. LPS reduced cell viability and proliferation and increased apoptosis, ROS production, BAX expression, and Caspase-3-related expression. RES partially reversed these changes, increased NRF2, HO-1, and SOD2 expression, and decreased KEAP1 expression under LPS-stimulated conditions. These RES-associated effects were partly weakened by ML385. Overall, RES may attenuate LPS-induced oxidative stress and apoptosis in HMC3 microglial cells, partly involving NRF2-related signaling. This study provides in vitro evidence supporting the potential protective role of RES in microglial injury related to postoperative neuroinflammation.

Pharmacological modulation of p75 neurotrophin receptor in microglial cells improves resilience to rotenone cytotoxicity

Introduction Parkinson’s disease (PD) is a progressive neurodegenerative disorder, characterized by dopaminergic neuronal loss, mitochondrial dysfunction, oxidative stress, and chronic neuroinflammation. Microglial activation plays a primary role in disease progression, by amplifying inflammatory response and redox imbalance. The low-affinity neurotrophin receptor p75NTR has recently emerged as a potential therapeutic target in neurodegenerative disorders, due to its involvement in cell survival, apoptosis, and inflammatory signaling. In the present study, we investigated whether pharmacological modulation of p75NTR by LM11A-31 could protect microglial cells against Rotenone (Rot)-induced toxicity, a widely used tool to mimic PD. Methods BV2 microglial cells were exposed to 50 nM Rot in the presence or absence of 0.5 μM LM11A-31. Cell viability, apoptotic signaling, oxidative stress, inflammatory response, and cytoskeletal organization were evaluated using immunofluorescence, Western blotting, TUNEL assay, and Scanning Electron Microscopy (SEM). Results Rot exposure significantly increased p75NTR expression and induced marked microglial dysfunction, characterized by activation of apoptosis, oxidative stress, and inflammatory phenotype. LM11A-31 treatment improved cell survival and reduced apoptotic features, as shown by decreased TUNEL+ cells and cleaved caspase-3 immunoreactivity. In parallel, LM11A-31 restored microglial morphology and cytoskeletal integrity, also reducing ultrastructural alterations induced by Rot. Moreover, p75NTR modulation significantly blunted microglial activation markers, including Iba1 and CD68. LM11A-31 also reduced oxidative stress by limiting NOX-related signaling and lipid peroxidation, while partially restoring antioxidant defenses through modulation of Nrf2, PPARα, and glutathione-associated pathways. Conclusion Our findings demonstrate that pharmacological modulation of p75NTR by LM11A-31 protects microglial cells against Rot-induced cytotoxicity and inflammatory activation. These protective effects involve the rescue of redox balance, suppression of pro-inflammatory signaling, preservation of cytoarchitecture, also resulting in increased cell survival. Overall, targeting p75NTR may represent a promising therapeutic strategy to counteract microglial dysfunction and neuroinflammatory processes associated with Parkinson’s disease.

Tetrandrine attenuates hypoxia-induced microglial M1 polarization and microglia-mediated photoreceptor cell injury through modulation of NF-κB/p65 signaling.

Diabetic retinopathy (DR), a primary cause of working-age vision loss, is characterized by neuroinflammation, in which microglial polarization toward the proinflammatory M1 phenotype serves as a pivotal driver. Reprogramming microglia toward an anti-inflammatory and reparative phenotype may therefore represent a promising therapeutic strategy. This study investigated the effects of tetrandrine (Tet) on hypoxia-induced microglial activation and explored the underlying mechanisms. We established a chemical hypoxia model using CoCl2 and evaluated inflammatory mediators and associated molecules by qRT-PCR, western blotting, and immunofluorescence. Microglial migratory and phagocytic functions were assessed by scratch wound and phagocytosis assays, respectively. Potential drug targets were identified through an integrative approach combining network pharmacology, molecular docking, and cellular thermal shift assay (CETSA). Tet suppressed CoCl2-induced M1-associated inflammatory gene expression in BV2 cells and attenuated p65 activation and cytotoxic responses in HMC3 cells. Functionally, Tet restored impaired phagocytic capacity, attenuated aberrant migration, and mitigated microglia-mediated injury to 661W photoreceptor-derived cells. Mechanistic analyses showed that Tet reduced p65 phosphorylation and apparent nuclear accumulation, thereby limiting activation of the HIF-1α/NF-κB signaling axis; docking and CETSA findings further supported a potential interaction between Tet and p65. In summary, Tet alleviates hypoxia-induced microglial M1 polarization and microglia-mediated photoreceptor cell injury, at least partly through modulation of NF-κB/p65 signaling. These findings identify Tet as a candidate compound for further preclinical investigation in retinal neuroinflammation associated with DR.

Enoxaparin induces apoptosis and autophagy, modulates inflammatory signaling, and reduces oxidative DNA damage in breast and liver cancer cells.

Cancer progression involves intricate interactions between inflammatory signaling, programmed cell death mechanisms, and oxidative stress. Although enoxaparin is widely used for managing cancer-associated thrombosis, its direct cellular effects on tumor biology remain insufficiently characterized. This study aimed to evaluate the impact of enoxaparin on apoptosis, autophagy, inflammatory mediators, and oxidative DNA damage in breast (MDA-MB-231) and liver (HepG2) cancer cell lines. MDA-MB-231, HepG2, and non-cancerous HEK-293 cells were treated with varying concentrations (5, 10, 20, 40, and 80 mg/mL) of enoxaparin for 24 and 48 h. Cell viability was assessed using the MTT assay, while apoptosis was quantified by TUNEL analysis. Immunofluorescence staining was employed to evaluate the expression of NF-κB, IL-6, TNF-α, LC3, and p62. Oxidative DNA damage was determined by measuring extracellular 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels using a competitive ELISA. Statistical analyses were conducted to compare the treated and control groups. Enoxaparin significantly reduced cell viability in MDA-MB-231 and HepG2 cells without inducing cytotoxicity in HEK-293 cells. Apoptosis was markedly increased in both cancer cell lines following treatment. Enoxaparin differentially modulated inflammatory signaling; NF-κB expression was significantly increased in MDA-MB-231 cells, accompanied by suppression of IL-6 and TNF-α, whereas no significant inflammatory changes were observed in HepG2 cells. Enoxaparin treatment was observed to increase LC3 and p62 expression in both MDA-MB-231 and HepG2 cells, triggering autophagy-related pathways. Moreover, enoxaparin significantly reduced extracellular 8-OHdG levels, suggesting a reduction in oxidative DNA damage. Enoxaparin exhibits multifaceted anticancer effects by promoting apoptosis and autophagy, selectively modulating inflammatory pathways, and reducing oxidative DNA damage in breast and liver cancer cells.

STAT6 Targets the Autophagy Pathway to Regulate Microglial Senescence in Cognitive Impairment Caused by Cerebral Small-Vessel Disease

Resveratrol and neuroprotection: modulation of cellular dynamics and signaling networks in neurodegenerative diseases