MOLECULAR MECHANISMS UNDERLYING RESVERATROL EFFECT ON RENAL OSMOPROTECTION: MODULATION OF COX-2 EXPRESSION

ERJAVEC, LUCIANA; PARRA LEANDRO; MOREL GOMEZ, EMANUEL; C.I. CASALI; DEL CARMEN FERNÁNDEZ, MARÍA

MENDOZA

Congreso; LVIII Reunión de la Sociedad Argentina de Investigaciones Bioquímicas y Biología Molecular- SAIB 2022? 8 al 11 de Noviembre de 2022, Ciudad de Mendoza, Argentina.; 2022

SAIB

MOLECULAR MECHANISMS UNDERLYING RESVERATROL EFFECT ON RENAL OSMOPROTECTION: MODULATION OF COX-2 EXPRESSIONErjavec LC, Parra LG, Morel Gomez E, Lampropulos T, Casali CI, Fernández MCCátedra de Biología Celular y Molecular, Facultad de Farmacia y Bioquímica, UBA, IQUIFIB-CONICET. E-mail: luerjavec@gmail.comResveratrol (RSV) is a polyphenol naturally present in several plants. Nowadays it is sold as an over-the-counter dietary supplement due to its antioxidant, anti-inflammatory and antitumoral effects. Paradoxically, it has been documented that RSV may also present pro-oxidizing and pro-proliferative effects. In fact, some studies suggest that RSV treatment can result in opposite effects depending on the cell type, its concentration, or the treatment time. Particularly in renal tissue, animal injury models described RSV beneficial effects, while studies with chronic intake of RSV observed nephrotoxicity. Hence, RSV effects on renal tissue are still controversial. medullary interstitium presentsIn this work we evaluate RSV effect on adaption and differentiation mechanisms, focusing particularly on COX-2 role. To do this, MDCK cells were pretreated with different concentrations of RSV (1, 5, 10, 25 μM) and cultured in hyperosmolar medium (~512 mOsm/kg H2O) for 24 and 48h. Cells were harvested to obtain cell number and viability. Cell cycle, immunofluorescence (IF), western blot and RT-PCR analysis were performed. We found that RSV significantly decreased cell number in a concentration-dependent manner at 24 and 48h. Cell cycle analysis revealed that RSV increased S-phase and Sub-G0 cell population. In addition, treated cells did not reach typical epithelium morphology. COX-2 mRNA and protein levels were surprisingly upregulated by RSV at 24 and 48h, and IF revealed an accumulation of the protein in cytoplasmic granules. To investigate the pathways leading to this upregulation, we indirectly evaluated TonEBP, NF-κB and ERK1/2 pathways, which are activated by hyperosmolarity; and SIRT1 implication, a target of RSV. TonEBP target genes mRNA did not show any significant change under RSV treatment, while NF-κB target gene mRNA presented an increase similar to that of COX-2 mRNA. Moreover, NF-κB IF revealed an increase in its nuclear localization. Regarding ERK1/2, treatment with ERK1/2 selective inhibitor (U0126) completely blocked COX- 2 protein expression. These results suggest that in renal cells RSV pretreatment decreased cell number and impeded typicalcell morphology acquisition; but it increased COX-2 expression, possibly through NF-κB and ERK1/2 activation.