ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Trifolium alexandrinum L. (TA), has traditionally been used in folk medicine for its anti-inflammatory properties against hyperuricemia and gout. However, the specific mechanisms of action of TA have not been thoroughly studied. AIM OF THE WORK: This study aimed to evaluate the protective effects of irradiated (TR25) and non-irradiated (TR0) Trifolium alexandrinum L. aqueous extract (TAAE), along with two isolated compounds, caffeine (CAF) and saponin (SAP), in a rat model of acute gouty arthritis (GA). MATERIALS AND METHODS: The GA model was established by injecting a monosodium urate (MSU) suspension into the knee joint. Synovial tissue pathology was assessed, and levels of TNF-α, IL-6, IL-1ß, NF-κB, mTOR, AKT1, PI3K, NLRP3, and ASC were measured by ELISA. mRNA expression of ERK1, JNK, and p-38 MAPK was detected using qRT-PCR, and Caspase-1 protein expression was assessed by immunohistochemical analysis. Knee swelling, uric acid levels, liver and kidney function, and oxidative stress markers were also evaluated. RESULTS: TAAE analysis identified 170 compounds, with 73 successfully identified using LC-HR-MS/MS, including caffeine citrate and theasapogenol B glycoside as the main constituents. The studied materials demonstrated significant protective effects against GA. TR25 administration significantly mitigated knee joint circumference compared to other treatments. It demonstrated potential in alleviating hyperuricemia, renal and hepatic impairments induced by MSU crystals. TR25 also alleviated oxidative stress and reduced levels of IL1ß, IL-6, TNF-α, and NF-κB. Weak Caspase-1 immune-positive staining was observed in the TR25 group. TR25 decreased NLRP3 and ASC expression, reducing inflammatory cytokine levels in GA. It effectively inhibited the PI3K, AKT, and mTOR signaling pathways, promoting autophagy. Additionally, TR25 suppressed ERK1, JNK, and p-38 MAPK gene expression in synovial tissue. These effects were attributed to various components in TAAE, such as flavonoids, phenolic acids, tannins, alkaloids, and triterpenes. CONCLUSION: Importantly, irradiation (25 KGy) enhanced the antioxidant effects and phtchemical contents of TAAE. Additionally, TR0, TR25, CAF, and SAP exhibited promising protective effects against GA, suggesting their therapeutic potential for managing this condition. These effects were likely mediated through modulation of the NLRP3/ASC/Caspase-1 and ERK/JNK/p-38 MAPK signaling pathways, as well as regulation of the PI3K/AKT/mTOR pathway. Further research is warranted to fully elucidate the underlying mechanisms and optimize their clinical applications.
ABSTRACT
Doxorubicin (DOX) so far continues to be one of the most potent and effective anticancer drugs. Therefore, it is still needed to search for a safe and effective therapy that can opposite DOX-induced cardiotoxicity. Irbesartan (IRB), an angiotensin II receptor blocker, has a wide-ranging variety of biological activities. The present study was designed to explore the possible protective effects of IRB against DOX-induced cardiotoxicity and the underlying mechanisms. Rats were divided into four groups: control, IRB (40 mg/kg, orally/daily) for 3 weeks, DOX (2.5 mg/kg, intraperitoneally/ three times weekly) for 2 weeks to obtain cumulative dose of 15 mg/kg, and finally IRB + DOX group. IRB inhibited cardiotoxicity induced by DOX which was evident by ECG changes, alterations of cardiac enzymes and histopathological changes. IRB improved DOX-induced alterations in oxidative/nitrosative status by decreasing lipid peroxidation and nitric oxide (NO) content in addition to increasing the antioxidant capacity. In addition, DOX triggers the cardiac expression of tumor necrosis factor-α (TNF-α) and nuclear factor kappa B (NF-κB) where IRB diminished DOX-induced alterations in theses parameters. Moreover, DOX significantly increase the expression levels of caspase-3 and transforming growth factor-beta 1 (TGF-ß1), while IRB exhibited anti-apoptotic and anti-fibrotic effects where it abolished these elevations. Meanwhile, DOX-induced activation of p38-mitogen activated protein kinase (p38-MAPK) which was inhibited by IRB. Collectively, these results proposed that IRB afforded a significant protection against DOX-induced cardiac damage by means of antioxidant, anti-inflammatory, anti-apoptotic, and anti-fibrotic remodeling mechanisms. These mechanisms are possibly mediated, at least in part, by alterations of TGF-ß1/p38-MAPK/NF-κB signaling.
