Expression of Stromal Derived Factor Alpha (SDF-1α) by Primary Hepatocytes Following Isolation and Heat Shock Stimulation

Abstract

Stromal derived factor-a (SDF-1-a) is a CXCchemokine which has been demonstrated as a recruitment factor for leukocytes to the site of inflammation, infection, injury and following stress. This chemokine has been shown to be expressed by liver cells and in liver diseases. Hence, the aim of this study was to examine the expression of SDF-1 by hepatocytes in responses to the stress imposed during isolation by collagenase perfusion and under heat shock stimulation.

In this study hepatocytes (2-5 x 10⁶) were isolated from male Sprague Dawley rat liver and cultured in plates that were pre-coated with collagen Type-I matrix. The western and northern blotting analysis were employed to detect SDF-1 at protein and mRNA levels in isolated and cultured hepatocytes in response to isolation and heat shock stresses.

The SDF-1 is expressed by isolated rat hepatocytes immediately after isolation and early culture and decreased with time. SDF-1 protein was highly expressed in freshly isolated cells and decreased by time (27h) (P<0.05). mRNA was also expressed in freshly isolated cells (0h) but decreased after 24h of culture (P<0.01). This results also demonstrated that expression of SDF-1 by hepatocytes was increased in response to heat shock at different time points comparing with control (P<0.01).

These results demonstrated that the isolation and heat shock stresses induced the expression of SDF-1 in hepatocytes in a time-dependent manner. Accordingly, it seems that hepatocytes mimic the experiences that liver experience after injury in vivo and therefore, produce stress related agents like chemokines to overcome such a injurious condition.