Hederasaponin C inhibits LPS-induced acute kidney injury in mice by targeting TLR4 and regulating the PIP2/NF-κB/NLRP3 signaling pathway.

Acute kidney injury (AKI) is a common clinical condition associated with increased incidence and mortality rates. Hederasaponin C (HSC) is one of the main active components of Pulsatilla chinensis (Bunge) Regel. HSC possesses various pharmacological activities, including anti-inflammatory activity. However, the protective effect of HSC against lipopolysaccharide (LPS)-induced AKI in mice remains unclear. Therefore, we investigated the protective effect of HSC against LPS-induced renal inflammation and the underlying molecular mechanisms. Herein, using MTT and LDH assays to assess both cell viability and LDH activity; using dual staining techniques to identify different cell death patterns; conducting immunoblotting, QRT-PCR, and immunofluorescence analyses to evaluate levels of protein and mRNA expression; employing immunoblotting, molecular docking, SPR experiments, and CETSA to investigate the interaction between HSC and TLR4; and studying the anti-inflammatory effects of HSC in the LPS-induced AKI. The results indicate that HSC inhibits the expression of TLR4 and the activation of NF-κB and PIP2 signaling pathways, while simultaneously suppressing the activation of the NLRP3 inflammasome. In animal models, HSC ameliorated LPS-induced AKI and diminished inflammatory response and the level of renal injury markers. These findings suggest that HSC has potential as a therapeutic agent to mitigate sepsis-related AKI.

Andrographolide/Phospholipid/Cyclodextrin Complex-Loaded Nanoemulsion: Preparation, Optimization, in Vitro and in Vivo Evaluation.

Andrographolide (AG), a natural product with various pharmacological effects, exhibited low oral bioavailability owing to its poor solubility, stability, and low absorption. Previous studies have suggested that phospholipid (PC) and hydroxypropyl-ß-cyclodextrin (HPCD) could improve the drug solubility and absorption. Moreover, nanoemulsion (NE) has been confirmed as an appropriate enhancer for oral bioavailability. Therefore, AG/HPCD/PC complex (AHPC) was synthesized, and AHPC-loaded nanoemulsion (AHPC-NE) was optimized and prepared using central composite design combined response surface methodology. The average droplet size and polydispersity index (PDI) were 116.50 ± 5.99 and 0.29 ± 0.03 nm, respectively. AHPC-NE with a loading capacity of 0.32 ± 0.01% and an encapsulation efficiency of 96.43 ± 2.27% appeared round and uniformly dispersed based on transmission electron microscopy. In vivo release studies demonstrated that AHPC-NE had good sustained-release effects. Further, AHPC-NE significantly enhanced the absorption of AG with a relative bioavailability of 550.71% compared to AG suspension. Such findings reveal AHPC-NE as a potential strategy for sustained-release and oral bioavailability enhancement.

[Research progress on liposome and nanomicelle targeted drug delivery system across blood-brain barrier].

The blood-brain barrier(BBB), a protective barrier between brain tissues and brain capillaries, can prevent drugs from entering the brain tissues to exert the effect, which greatly increases the difficulty in treating brain diseases. The drug delivery system across the BBB can allow efficient drug delivery across the BBB by virtue of carriers and formulations, thereby enhancing the therapeutic effect of drugs on brain tissue diseases. Liposomes and micelles have been extensively studied with advances in the targeted therapy across the BBB for the brain due to their unique structures and drug delivery advantages. This study summarized the research status of liposome and micelle drug delivery systems across the BBB based on the literature in recent years and analyzed their application advantages and mechanism in terms of trans-BBB capability, targeting, and safety. Moreover, the problems and possible countermeasures in the research on trans-BBB liposomes and micelles were discussed according to the current clinical translation, which may provide refe-rences and ideas for the development of trans-BBB targeted nano-drugs.

Oleuropein alleviates myocardial ischemia-reperfusion injury by suppressing oxidative stress and excessive autophagy via TLR4/MAPK signaling pathway.

BACKGROUND: Myocardial ischemia/reperfusion injury (MIRI) is an important complication of reperfusion therapy, and has a lack of effective prevention and treatment methods. Oleuropein (OP) is a natural strong antioxidant with many protective effects on cardiovascular diseases, but its protective effect on MIRI has not yet been studied in depth. METHODS: Tert-Butyl hydroperoxide (tBHP) was used to establish an in vitro oxidative stress model. Cell viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) and lactate dehydrogenase (LDH). Flow cytometry and fluorescence assays were performed for evaluating the ROS levels and mitochondrial membrane potential (MMP). Immunofluorescence analysis detected the NRF2 nuclear translocation and autophagy indicators. Further, Western blotting and quantitative real-time PCR were performed to evaluate the expression levels of proteins and mRNAs. Molecular docking, CETSA, and molecular interaction analysis explored the binding between OP and TLR4. The protective effects of OP in vivo were determined using a preclinical MIRI rat model. RESULTS: OP protected against tBHP-treated injury, reduced ROS levels and reversed the damaged MMP. Mechanistically, OP activated NRF2-related antioxidant pathways, inhibited autophagy and attenuated the TLR4/MAPK signaling pathway in tBHP-treated H9C2 cells with a high binding affinity to TLR4 (KD = 37.5 µM). The TLR4 inhibitor TAK242 showed a similar effect as OP. In vivo, OP could alleviate cardiac ischemia/reperfusion injury and it ameliorated adverse cardiac remodeling. Consistent with in vitro studies, OP inhibited TLR4/MAPK and autophagy pathway and activated NRF2-dependent antioxidant pathways in vivo. CONCLUSION: This study shows that OP binds to TLR4 to regulate oxidative stress and autophagy for protecting damaged cardiomyocytes, supporting that OP can be a potential therapeutic agent for MIRI.