Zygo-Albuside A: New Saponin from Zygophyllum album L. with Significant Antioxidant, Anti-Inflammatory and Antiapoptotic Effects against Methotrexate-Induced Testicular Damage

Abstract

Chemical investigation of the crude extract of the aerial part of Zygophyllum album L. (Z. album) led to the isolation of a new saponin, Zygo-albuside A (7), together with seven known compounds, one of them (caffeic acid, compound 4) is reported in the genus for the first time. NMR (1D and 2D) and mass spectrometric analysis, including high-resolution mass spectrometry (HRMS), were utilized to set up the chemical structures of these compounds. The present biological study aimed to investigate the protective antioxidant, anti-inflammatory, and antiapoptotic activities of the crude extract from the aerial part of Z. album and two of its isolated compounds, rutin and the new saponin zygo-albuside A, against methotrexate (MTX)-induced testicular injury, considering the role of miRNA-29a. In all groups except for the normal control group, which received a mixture of distilled water and DMSO (2:1) as vehicle orally every day for ten days, testicular damage was induced on the fifth day by intraperitoneal administration of MTX at a single dose of 20 mg/kg. Histopathological examination showed that pre-treatment with the crude extract of Z. album, zygo-albuside A, or rutin reversed the testicular damage induced by MTX. In addition, biochemical analysis in the protected groups showed a decrease in malondialdehyde (MDA), interleukin-6 (IL-6) and IL-1β, Bcl-2-associated-protein (Bax), and an increase in B-cell lymphoma 2 (Bcl-2) protein, catalase (CAT), superoxide dismutase (SOD) in the testis, along with an increase in serum testosterone levels compared with the unprotected (positive control) group. The mRNA expression levels of nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α), p53, and miRNA-29a were downregulated in the testicular tissues of the protected groups compared with the unprotected group. In conclusion, the study provides sufficient evidence that Z. album extract, and its isolated compounds, zygo-albuside A and rutin, could alleviate testicular damage caused by the chemotherapeutic agent MTX.