Clinical and Experimental Pharmacology and Physiology最新文献

The study aimed to investigate the neuroprotective functions and the underlying regulatory mechanisms of Tabersonine in cerebral ischemia/reperfusion (I/R) injury. Oxygen–glucose deprivation/reoxygenation (OGD/R)-treated neural cells were used as a cell model under I/R context. Cell counting kit 8 (CCK8) assay and enzyme-linked immunosorbent assay (ELISA) were used to assess the cell viability and the release levels of inflammatory cytokines (interleukin-1β (IL-1β), IL-6 and tumour necrosis factor α (TNF-α)) of treated neural cells. The apoptotic proportions of treated neural cells were analysed by flow cytometry, and the intracellular levels of reactive oxygen species (ROS) and superoxide dismutase (SOD) were quantified by corresponding kits. In this study, molecular docking analysis identified solute carrier family 6 member 2 (SLC6A2) as a potential target of Tabersonine in cerebral infarction, demonstrating a high binding affinity of −7.4 kcal/mol. Tabersonine treatment increased neural cell viability, repressed apoptosis and reduced the release levels of IL-1β, IL-6 and TNF-α under OGD/R stress. Moreover, Tabersonine treatment reduced ROS levels and increased SOD expression in neural cells under OGD/R treatment. In contrast to the protective effect of SLC6A2 knockdown, its overexpression counteracted the neuroprotection conferred by Tabersonine. Tabersonine also inactivated the NF-κB pathway partially via SLC6A2. Furthermore, Tabersonine pretreatment demonstrated significant neuroprotective effects in MCAO/R rats, as evidenced by reduced brain edema and attenuated neural inflammation and apoptosis. In conclusion, Tabersonine can alleviate neural impairment in cerebral I/R injury partially by inactivating the NF-κB pathway through SLC6A2.

Bupivacaine, a commonly used aminoamide local anaesthetic, exerts cellular effects beyond anaesthesia. However, its effects on calcium (Ca²⁺) signalling and the physiological responses of lung fibroblasts remain insufficiently characterised. This study aimed to determine whether bupivacaine disrupts intracellular Ca²⁺ homeostasis and induces cytotoxicity in IMR-90 human foetal lung fibroblasts via Ca²⁺-dependent mechanisms. Cell viability was assessed using the CCK-8 assay, and intracellular Ca²⁺ levels ([Ca²⁺]ᵢ) were monitored in fura-2-loaded cells. Pharmacological inhibitors were used to dissect the signalling pathways involved. Bupivacaine (20–60 μM) caused a concentration-dependent rise in [Ca²⁺]ᵢ and a corresponding decline in cell viability. These effects were significantly attenuated by pre-treatment with the Ca²⁺ chelator BAPTA-AM, indicating a Ca²⁺-dependent cytotoxic mechanism. Mechanistically, bupivacaine induced Ca²⁺ influx through store-operated Ca²⁺ entry (SOCE), involving protein kinase C (PKC), and triggered Ca²⁺ release from the endoplasmic reticulum (ER) via a phospholipase C (PLC)-dependent pathway. Mn²⁺ quenching assays confirmed SOCE as the primary route of Ca²⁺ entry. Bupivacaine disrupts Ca²⁺ signalling through both extracellular influx and intracellular release, contributing to pulmonary cytotoxicity. These findings underscore the relevance of Ca²⁺ homeostasis in anaesthetic-related lung injury and suggest that Ca²⁺ chelation may be a potential protective strategy.

Pancreatic cancer (PaCa) manifests as an aggressive tumour due to the late occurrence of early symptoms. The overall 5-year survival rate of PaCa is merely 2%–9%. Bharangin (BG), a diterpenoid quinonemethide known for its anti-cancer activities, was investigated in a preclinical PaCa model. A dose- and time-dependent suppression in the viability of PaCa cells was observed by BG. The diterpenoid suppressed the level of tumorigenic proteins in PaCa cells. As evident from phosphatidylserine externalisation, acridine orange (AO)/propidium iodide (PI) staining, cell cycle analysis and DNA laddering, BG was found to induce apoptosis in PaCa cells. An accumulation in the sub-G1 population was observed by BG. The diterpenoid induced depolarization in the mitochondrial membrane potential and enhanced the PaCa cells' sensitivity to gemcitabine (GEM). The cancer-associated lncRNAs were also modulated by both BG and GEM in PaCa cells. BG also suppressed the p65 nuclear translocation induced by TNF-α in PaCa cells. Overall, BG exhibits activities in PaCa cells. The suppression of NF-κB activation and the modulation of lncRNAs expression may provide a basis for further exploration of BG as a therapeutic agent in PaCa.

Pulmonary hypertension (PH) is a progressive and fatal disease characterised by pulmonary vascular remodelling, right ventricular hypertrophy, and increased pulmonary arterial pressure. Apelin, an endogenous ligand of the APJ receptor, exerts cardioprotective and vasoprotective effects and has been proposed as a potential therapeutic agent in PH. This study aimed to investigate the therapeutic effects of Apelin-13 on hemodynamic, histomorphological, and molecular alterations in a monocrotaline (MCT)-induced PH rat model. Male Wistar rats were divided into four groups: control, MCT, MCT + Apelin-13, and sham-Apelin. A single intraperitoneal injection of MCT (60 mg/kg) was used to induce PH. Apelin-13 was administered intraperitoneally for 21 days. Hemodynamic parameters (P_max, P_min, mPAP, EDP, dP/dt_max, dP/dt_min, MAP), morphometric indices (RVHI, PAWTR, PAVR), histological and immunohistochemical analyses (Apelin-13, ACE, Caspase-3, IL-1β) were evaluated. MCT administration significantly increased pulmonary arterial pressure, right ventricular hypertrophy, and vascular wall thickness, while reducing Apelin-13 and ACE expression and elevating Caspase-3 and IL-1β levels. Apelin-13 treatment markedly attenuated these pathological alterations by lowering right ventricular overload, improving vascular remodelling, restoring Apelin-13 and ACE expression, and reducing apoptotic and inflammatory markers. Apelin-13 exerts multifaceted protective effects in MCT-induced PH by modulating hemodynamic load, vascular structure, and inflammatory-apoptotic pathways. These findings provide novel evidence supporting Apelin-13 as a promising therapeutic candidate for PH and warrant further studies to explore its long-term efficacy and translational potential.

Nontuberculous mycobacteria (NTM) infections, especially those caused by Mycobacterium abscessus, are extremely difficult to treat due to the organisms' intrinsic resistance to many antimicrobials. Myxin is a naturally occurring phenazine-5,10-dioxide antibiotic from Sorangium sp., notable for its broad-spectrum antimicrobial activity. In this study, we determined the susceptibilities of Myxin against 11 NTM reference strains and 194 clinical M. abscessus isolates using microdilution assays. Additionally, time-kill kinetic experiments were performed to distinguish the clearing efficiency of Myxin in broth. We also evaluated the efficacy of Myxin against intracellular M. abscessus in THP-1 macrophages. Checkerboard assays assessed the interactions between Myxin and eight clinically important anti-NTM antibiotics. Myxin demonstrated potent activity against M. abscessus with low MIC values (MIC₅₀ = 0.125 mg/L and MIC₉₀ = 0.5 mg/L). Treatment with 20 × MIC of Myxin in 7H9 broth resulted in up to 10 log₁₀ CFU/mL reduction after 4 days of incubation. An intracellular concentration-dependent bactericidal effect of Myxin was observed in THP-1 macrophages. Myxin exhibited no antagonism in combination with standard anti-NTM drugs. As such, Myxin represents a promising candidate for the treatment of M. abscessus and other NTM infections.