Abstract
Cardiac tissue contains a heterogeneous population of cardiomyocytes and nonmyocyte
population especially fibroblasts. Fibroblast differentiation into adipogenic lineage
is important for fat accumulation around the heart which is important in cardiac pathology.
The differentiation in fibroblast has been observed both spontaneously and due to
increased insulin stimulation. The present study aims to observe the effect of insulin
in adipogenic differentiation of cardiac cells present in primary murine cardiomyocyte
cultures.
Oil Red O (ORO) staining has been used for observing the lipid accumulations formed
due to adipogenic differentiation in murine cardiomyocyte cultures. The accumulated
lipids were quantified by ORO assay and normalized using protein estimation. The lipid
accumulation in cardiac cultures did not increase in presence of insulin. However,
addition of other growth factors like insulin-like growth factor 1 and epidermal growth
factor promoted adipogenic differentiation even in the presence of insulin and other
inhibitory molecules such as vitamins. Lipid accumulation also increased in cells
grown in media without insulin after an initial exposure to insulin-containing growth
media.
The current study adds to the existing knowledge that the insulin by itself cannot
induce adipogenic induction in the cardiac cultures. The data have significance in
the understanding of cardiovascular health especially in diabetic patients.
Keywords
primary cardiomyocyte culture - fibroblasts - adipogenic differentiation - insulin
- growth factors
