Specneuzhenide improves bleomycin-induced pulmonary fibrosis in mice via AMPK-dependent reduction of PD-L1.

BACKGROUND: Pulmonary fibrosis (PF) is an escalating global health issue, characterized by rising rates of morbidity and mortality annually. Consequently, further investigation of potential damage mechanisms and potential preventive strategies for PF are warranted. Specnuezhenide (SPN), a prominent secoiridoid compound derived from Ligustrum lucidum Ait, exhibits anti-inflammatory and anti-oxidative capacities, indicating the potential therapeutic actions on PF. However, the underlying mechanisms of SPN on PF remain unclear. PURPOSE: This work was aimed at investigating the protective actions of SPN on PF and the potential mechanism. METHODS: In vivo, mice were administrated with bleomycin (BLM) to establish PF model. PF mice were treated with SPN (45/90 mg/kg) by gavage. In vitro, we employed TGF-ß1 (10 ng/mL)-induced MLE-12 and PLFs cells, which then were treated with SPN (5, 10, 20 µM). DARTS assay, biofilm interference experiment and molecular docking were performed to investigate the molecular target of SPN. RESULTS: In vivo, we found SPN treatment improved survival rate, alleviated pathological changes through reducing BLM-induced extracellular matrix (ECM) deposition, as well as BLM-induced epithelial-mesenchymal transition (EMT). In vitro, SPN inhibited EMT and lung fibroblast transdifferentiation. Mechanistically, SPN activated the AMPK protein to decrease the abnormally high level of PD-L1. Furthermore, the compound C, known as an AMPK inhibitor, exhibited a significant hindrance to the inhibition of SPN on TGF-ß1-caused fibroblast transdifferentiation and proliferation. This outcome could be attributed to the fact that compound C could eliminate the inhibitory effects of SPN on PD-L1 expression. Interestingly, DARTS assay, biofilm interference experiment and molecular docking results all indicated that SPN could bind to AMPK, which suggested that SPN might be a potential agonist targeting AMPK protein. CONCLUSION: Altogether, the results in our work illustrated that SPN promoted AMPK-dependent reduction of PD-L1 protein, contributing to the inhibition of fibrosis progression. Thus, SPN may represent a potential AMPK agonist for PF treatment.

Cerebral neurotoxicity of amino-modified polystyrene nanoplastics in mice and the protective effects of functional food Camellia pollen.

Accumulating evidence suggests that nanoplastics contribute to an increased risk of brain damage, however, the precise underlying mechanisms remain unclear. Here, we subjected mice to long-term exposure to amino-modified polystyrene nanoplastics (APS-NPs). These nanoplastics were detected in the mouse brain; coupled with the observed upregulation of Alzheimer's disease-associated genes (APP and MAPT). To further explore nanoplastic damage mechanisms and the corresponding protective strategies against these mechanisms in vitro, we used hCMEC/D3 and HT22 cells. Results showed that APS-NPs disrupted tight junction proteins (Occludin and ZO-1) via TLR2/MMP9 axis, resulting in blood-brain barrier permeation; this was significantly mitigated by functional food Camellia pollen treatment. APS-NPs initiated iNOS and nNOS upregulation within neurons resulting in Sirtuin 1 deacetylase inactivation and CBP acetyltransferase stimulation, ultimately leading to Ac-Tau formation. This process was attenuated by Camellia pollen, which also ameliorated the APS-NPs-induced neuronal apoptosis mediated by the p53/Bax/Bcl-2 axis. Network pharmacology analysis of Camellia pollen offered a further theoretical understanding of its potential applications in preventing and treating nervous system disorders, such as Alzheimer's disease. This study established that Camellia pollen protects the brain against APS-NPs-mediated blood-brain barrier damage and alleviates neuronal apoptosis and Alzheimer's disease-like neurotoxicity. This study elucidates the mechanisms underlying polystyrene-induced brain damage and can be used to inform future prevention and treatment strategies.

Renoprotective activity of Ribes diacanthum pall (RDP) against inflammation in cisplatin-stimulated mice model and human renal tubular epithelial cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Ribes diacanthum Pall (RDP) is mostly distributed in Mongolia. As a Mongolian folk medicinal plant, it is traditionally used to treat kidney diseases by the native inhabitants of Mongolia due to its effect of increasing urine output and eliminating edema. However, its renal protection mechanism remains to be elucidated. AIM OF THE STUDY: To assess the pharmacological mechanism of RDP from an anti-inflammatory point of view using cisplatin (CDDP)-induced kidney injury models in vivo and in vitro. The influence of RDP on the chemotherapy efficacy of CDDP was also evaluated in vitro. MATERIALS AND METHODS: We established a CDDP-induced nephrotoxicity mouse model and a Human Renal Tubular Epithelial (HK-2) damage cellular model, respectively. In vivo, kidney function, the content of urine albumin, and renal histopathology examination were performed to observe the kidney injury. Moreover, the expression and secretion of inflammatory cytokines and adhesive molecules were examined by enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), and real-time PCR. The key protein levels of mitogen-activated protein kinase/nuclear factor kappa B (MAPK/NF-κB) signaling pathway were measured by western blotting analysis. Electrophoretic mobility shift assay (EMSA) was carried out to detect the activation of NF-κB. In vitro, inflammatory mediators and the proteins related to the NF-κB signaling pathway in HK-2 cells were measured by western blotting analysis. Besides, A549 cell lines were treated with CDDP and RDP to explore RDP's impact on CDDP chemotherapy. RESULTS: Gavage RDP decreased the elevated levels of serum creatinine (Scr), urea nitrogen (BUN), as well as the ratio of urine albumin and creatinine, ameliorated pathological changes of kidney tissue. Correspondingly, the RDP administration group showed a higher survival rate than that of the CDDP exposed group. The expression levels of a plethora of inflammatory mediators were inhibited by RDP treatment compared with the CDDP-exposed group. Furthermore, protein expression levels of MAPK/NF-κB signaling pathway significantly decreased after RDP intervention. For in vitro studies, we confirmed the inhibitory effect of RDP on relative protein expressions involving in the NF-κB pathway. The results also showed that RDP had no impairment on the inhibitory effect of CDDP on A549 cells. CONCLUSION: These findings demonstrated RDP's anti-inflammatory effect against CDDP nephrotoxicity through in vivo and in vitro experiments, and suggested that RDP may have a potential application as an adjuvant medication for CDDP chemotherapy and other inflammatory kidney diseases.