Osthole: A potential AMPK agonist that inhibits NLRP3 inflammasome activation by regulating mitochondrial homeostasis for combating rheumatoid arthritis.

BACKGROUND: Osthole (OST), a characteristic coumarin compound in Angelicae pubescentis radix (APR), has shown potent efficacy in the treatment of rheumatoid arthritis (RA), but its specific targets and potential mechanism are limited. PURPOSE: This study aimed to explore the potential targets and molecular mechanisms of OST against RA using computer-assisted techniques in combination with RA fibroblast-like synoviocytes (FLS) inflammation model and CIA rat model. METHODS: Network pharmacology and molecular docking were applied to initially predict the potential targets of OST for the treatment of RA. Thereafter, TNFα was used to stimulate FLS to build an in vitro model of inflammation, combined with RNA-seq technology and molecular biology such as qPCR to investigate the anti-inflammatory effects and related mechanisms of OST. Finally, the anti-RA effect of OST was demonstrated by establishing a CIA rat model. RESULTS: The network model results showed that the anti-RA effect of OST was mainly related to its anti-inflammatory effect, and AMPK was identified as a potential target for the potency of OST. In the TNFα-induced FLS cells, OST inhibited the secretion of FLS inflammatory factors, which was attributed to the ability of OST to activate AMPK to inhibit the activation of the NLRP3 inflammasome. Further, it was observed that the activation of AMPK by OST facilitated mitochondrial biogenesis, and corrected abnormal mitochondrial dynamics in FLS, which was favoured to the restoration of mitochondrial homeostasis, and further promoted the occurrence of apoptosis and the decrease of ROS in FLS. Consistent with in vivo studies, administration of OST significantly improved joint deformity and toe erythema, reduced arthritis index scores and inhibited synovial inflammation in CIA rats. CONCLUSION: Our study proposed for the first time that AMPK, served as a potential target of OST, positively participated in the anti-RA therapeutic effect of OST. By regulating mitochondrial homeostasis and function, OST can effectively inhibit the activation of inflammasome and the secretion of inflammatory factors in vitro and in vivo, and finally achieve beneficial effects in the treatment of RA, which provides support and greater possibility to make further efforts on pharmacological research and clinical application of OST.

Integrating metabolomics and network pharmacology to investigate Panax japonicus prevents kidney injury in HFD/STZ-induced diabetic mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax japonicus C. A. Meye (PJ) has unique effects on diseases by "qi" stagnation and blood stasis in ancient. Modern studies have shown that PJ can treat diabetic kidney disease (DKD) caused by deficiency and blood stasis. AIM OF THE STUDY: This study evaluated the potential effects of PJ on DKD, a microvascular complication, and investigated its possible mechanisms. MATERIALS AND METHODS: In this study, the chemical constituents of PJ were analyzed by HPLC. In vivo studies, we constructed a diabetic mice model by HDF combined with STZ, then administered PJ to diabetic mice for 6 weeks. Blood lipid, BUN, 24h urine protein, and renal tissue HE staining were detected to comprehensively evaluate the protective effect of PJ on DKD. Metabolomics investigated the metabolic pathways influenced by PJ in the treatment of DKD. Moreover, the potential targets and signal pathways were investigated using network pharmacology. Finally, molecular docking predicts affinity of active compounds and core targets, and western blotting was used to detect core target expression levels. RESULTS: In vivo study, PJ can reduce hyperlipidemia, serum BUN, and 24-h urinary protein in diabetic mice, and protect the pathological changes in renal tissue. Metabolomics results showed that PJ had significant regulatory effect on unsaturated fatty acids, glycerophospholipid metabolism, and purine metabolism. Network pharmacology showed that MAPK1, MAPK8, Bcl-2, and Caspase 3 were the core targets in PJ against DKD. Molecular docking revealed that Bcl-2 and Caspase 3 have a strong affinity for Chikusetsusaponin Iva, Ginsenoside Rb1, and Ginsenoside Rg1. Moreover, when compared to the model group, the PJ group had higher levels of anti-apoptosis protein Bcl-2 and lower levels of pro-apoptosis protein Caspase 3. CONCLUSION: PJ can reduce blood lipids, regulate the biosynthesis of unsaturated fatty acids and purine metabolism, thereby alleviating the renal injury of diabetic mice. Moreover, it can regulate the Bcl-2/caspase 3 apoptosis signaling pathway to prevent the apoptosis of renal cells and protect the renal function of diabetic mice.

Redox-Sensitive Ultrashort Peptide Hydrogel with Tunable Mechanical Properties for Anti-Tumor Drug Delivery.

In this study, we report a new ultrashort peptide (LOC), which forms a redox-sensitive hydrogel after cross-linking with the mild oxidant H2 O2 and used it for tumor-targeted delivery of doxorubicin hydrochloride (DOX). LOC gelled within a few minutes in low-concentration H2 O2 solution. The concentration of H2 O2 significantly altered the gelation time and mechanical properties of the hydrogel. The in vitro micromorphology, secondary structure and rheology characterization of cross-linked hydrogels confirmed the sensitivity and injectability to reducing agent. The cross-linked hydrogel had a strong drug loading capacity, and the drug was released in a GSH concentration-dependent manner, following the Fick diffusion model. In addition, the cross-linked hydrogel showed no cytotoxicity to normal fibroblasts, and no damage to the subcutaneous tissue of mice was observed. In vitro cytotoxicity experiments showed that the DOX-hydrogel system exhibited good anti-cancer efficacy. In vivo studies using 4T1 tumor-bearing mice showed that the DOX-hydrogel system had a significant inhibitory effect on tumors. Therefore, the newly designed redox-sensitive hydrogel can effectively enhance the therapeutic efficacy of DOX and reduce toxicity, making it an attractive biological material.