BECAS
PARRA Leandro GastÓn
congresos y reuniones científicas
Título:
Triglycerol synthesis dynamics under hyperosmolar stress.
Autor/es:
WEBER, K; CASALI, CI; PARRA, L; FERNÁNDEZ-TOME, MC
Lugar:
Buenos Aires
Reunión:
Congreso; XLIX Reunión de la Sociedad Argentina de Investigaciones Bioquimicas y Biología Molecular; 2013
Institución organizadora:
SAIB
Resumen:
Renal medullary cells are immersed in a hyperosmolar
environment due to their function in the urine concentrating system. In order
to survive in these conditions, cells must develop protective mechanisms. We showed
that the renal papilla is the zone with the highest content and synthesis of
phospholipids (PL), which helps to preserve the membrane structure and cell
viability. Triglycerides (TG) are a possible source of fatty acids for the
synthesis of PL. In this work we study the dynamics of TG and PL synthesis in
renal epithelial cells subjected to hyperosmolarity. We studied lipid synthesis
in renal medullary slices and in MDCK cells submitted to different hyperosmolar
media (from 298 to 579 mOsm/kgH2O) by using different precursors: [U14C]-glycerol,
[14C]-arachidonic acid (AA), [14C]-palmitic acid and [3H]-oleic
acid. After treatment lipids were extracted, separated by TLC and quantified by
liquid scintillation. We observed that high osmolarities increase TG and PL
synthesis in all the samples assayed. All precursors were incorporated to both TG
and PL molecules except for the AA which was found only in PLs. Cerulenin, a
FAS inhibitor used to suppress fatty acid de novo synthesis, decreases TG
synthesis and content while PL synthesis remains active. These results show
that molecular machinery involved in lipid metabolism is differentially
regulated by hyperosmolarity.