Phytoconstituents and renoprotective effect of Polyalthia longifolia leaves extract on radiation-induced nephritis in rats via TGF-β/smad pathway

Renoprotectors are highly demanded due to environmental nephrotoxic factors. P. longifolia leaves extract alleviating effect was assessed in nephritic-induced rats by whole body shot dose of gamma-radiation. Many biomarkers were detected using several assays. Renohistopathological examinations were performed. Moreover, the extract phytoconstituents were identified using spectroscopic analysis. In-vitro anti-inflammatory activity of some compounds was examined using histamine release assay. Post-irradiation treatment with the extract significantly ameliorated all elevated biomarker levels. Creatinine and urea were adjusted, TGF-beta/Smad signaling was suppressed causing down-regulation to microRNA-21. Nitric oxide, reactive oxygen species, glutathione and kidney injury molecule-1 were normalized in comparison with the gamma-irradiated group. The renohistopathological analysis was consistent with the biochemical study. Phytochemical analysis resulted in the isolation of two diterpenoids (gamma-methoxybutenolide clerodane diterpene and 16(R/S)-hydroxycleroda-3,13-dien-16,15-olide-2-one), aporphine alkaloid (anonaine) and flavonol (kaempferol-3-O-rutinoside). The latter two showed moderate anti-histaminic activities. Our results indicated that P. longifolia reduced oxidative stress and nephropathy in rats due to its anti-inflammatory principles.

Automated summary

The study showed that P. longifolia extract relieved nephritic symptoms induced by gamma-radiation in rats by reducing biomarker levels, regulating various signaling pathways, normalizing oxidative stress and kidney injury molecule levels, and exhibiting anti-inflammatory effects. Phytochemical analysis identified compounds with moderate anti-histaminic activities, highlighting the potential renoprotective benefits of P. longifolia.