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Updated: Jul 9, 2026
08:34
Mechanism of Regulation of Adipocyte Numbers in Adult Organisms Through Differentiation and Apoptosis Homeostasis
Published on: June 3, 2016
Regulation of adiponectin in adipocytes upon exposure to HIV-1
J-L G Sankalé1, Q Tong, C M Hadigan
1Department of Immunology & Infectious Diseases and Harvard AIDS Institute, Harvard School of Public Health, Boston, MA, USA.
HIV Medicine
|April 25, 2006
Summary
Human immunodeficiency virus (HIV) exposure increases adiponectin secretion from fat cells without infection. This stimulation may explain altered adiponectin levels in HIV patients, impacting metabolic health.
Area of Science:
- Endocrinology
- Virology
- Immunology
Background:
- HIV-associated lipodystrophy involves adipose tissue dysfunction, dyslipidemia, and insulin resistance.
- Adiponectin, an adipose-derived hormone, plays a crucial role in glucose and lipid metabolism.
- Previous studies linked lipodystrophy in HIV patients to altered adiponectin levels.
Purpose of the Study:
- To investigate the direct effect of HIV on human adipocytes.
- To determine if HIV infects adipocytes.
- To assess HIV's impact on adiponectin regulation and secretion by adipocytes.
Main Methods:
- Human preadipocytes and adipocytes were exposed to HIV-1 in vitro.
- Adiponectin levels were measured in cell supernatants and lysates.
- Transwell assays were used to study sustained HIV exposure.
Main Results:
- Adipocytes expressed the HIV receptor CD4 but were not infected by HIV in vitro.
- HIV exposure significantly increased adiponectin secretion from adipocytes.
- Sustained HIV exposure further enhanced adiponectin secretion.
Conclusions:
- HIV can stimulate adiponectin production in adipocytes without direct infection.
- This HIV-induced stimulation may lead to dysregulated adiponectin levels.
- These findings suggest a molecular mechanism for adiponectin dysregulation in HIV patients.
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