MODULATION OF THE DIFFERENTIATION PROCESS OF HUMAN INTESTINAL CACO-2 CELLS BY PHOSPHATIDYLCHOLINE

ARANA MAITE ROCÍO; VILLANUEVA SILVINA; TOCCHETTI GUILLERMO NICOLÁS; MOTTINO ALDO DOMINGO; DOMÍNGUEZ CAMILA JULIANA; ZECCHINATI FELIPE; BANCHIO CLAUDIA

Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias; 2017

In addition to its absorptive function, the intestine represents animportant barrier that limits the entry of harmful substances. Thiscapacity is conditioned by an adequate balance between cell proliferationand differentiation, which guarantees the development ofboth mature enterocytes (transcellular barrier) and tight junctions(paracellular barrier). We demonstrated that phospholipids promotedifferentiation of neuroblastoma and neural stem cells, but it is unknownwhether they regulate the differentiation process at the intestinallevel.Aim: To evaluate the effect of phosphatidylcholine (PtdCho) on thebalance proliferation-differentiation in Caco-2 cells, a model of humanintestinal epithelium.Methods: The expression of proliferation/differentiation markerswas evaluated by immunoblot between days 4 and 21 of culture.Localization of Zonula occludens-1 (ZO-1), a tight junction protein,was assessed by confocal microscopy.Results: Cells cultured for 21 days under basal conditions, showedprogressive increase in expression of the microvilli structural proteinvillin with time, consistent with morphological differentiation. Bycontrast, we found a progressive decrease in expression of PCNA,indicating decreasing proliferation. ZO-1 changed its localizationwith time, from an intracellular, homogeneous pattern to a peripherallocalization, without changes in its total expression. After PtdCho-treatment(40 ѥM) we observed an increase in villin expression(33% and 22% at day 14 and 21, p0.05) and a decreasein PCNA expression (-34%, -21% and -9% at day 7, 14 and 21,p0.05) when compared to control cells. The expression of the tumormarker choline kinase also showed a decrease in response toPtdCho (-18% and -29% at day 14 and 21, p0.05), confrming ashift in the proliferation/differentiation balance.Conclusion: PtdCho accelerated Caco-2 cells differentiation process,suggesting a potential application as a modulator of regenerativeand neoplastic processes.