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Indian Journal of Clinical Biochemistry

, Volume 21, Issue 1, pp 8–14 | Cite as

Estradiol regulates insulin dependent stimulation of LDL-receptor expression in HepG2 cells

  • Gopalakrishnan R. 
  • N. C. ChandraEmail author
Article

Abstract

The low density lipoprotein, one of the major vehicle for extraneous cholesterol, internalizes into the cells through the process of LDL-receptor mediated endocytosis. The expression of LDL-receptor on the cell surface is a function of various hormone regulated transcription of the receptor gene. The present study elucidates the differential expression pattern of LDL-receptor protein in human hepatoma HepG2 cells by the influence of two hormones, insulin and estrogen (β-estradiol), as compared to the basal level expression of the receptor protein. The combined effect of insulin and β-estradiol reveals that β-estradiol is the ultimate regulator between these two hormones and supershades the message of insulin on LDL-receptor expression. The receptor protein level immunobloted by anti LDL-receptor antibody after treating cells with insulin, β-estradiol and mixture of both also reflects the same phenomena. This comparative study makes it consistent that cell saturation with sterol (β-estradiol) is the prime regulator of LDL-receptor expression between the two hormones, insulin and estrogen.

Keywords

LDL-receptor Estrogen Insulin HepG2 cells Cholesterol 

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Copyright information

© Association of Clinical Biochemists of India 2006

Authors and Affiliations

  1. 1.Department of BiochemistryAll India Institute of Medical SciencesNew DelhiIndia

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