MedicalResearch.com Interview with:
Dr. Audrey Chu
Audrey Chu, Ph.D.
Division of Intramural Research
National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Body shape reflects the underlying adipose tissue distributed throughout different compartments of the body (ectopic fat). Variation in ectopic fat is associated with diabetes, hypertension and heart disease. This is mostly independent of overall adiposity. Ectopic fat can be measured using special x-rays procedures such as CT (“CAT scans”) or MRI and can give more information about fat distribution. Fat distribution characteristics can run in families, suggesting that a person’s genes can help determine the amount of fat that can accumulate in different parts of the body. Identifying genes that are associated with ectopic fat can provide insight into the biological mechanisms leading to differences in cardiometabolic disease risk.
In order to understand which genes might be involved, we examined genetic variants across the genome and their association with ectopic fat in the largest study of its kind including over 18,000 individuals of four different ancestral backgrounds.
Several new genetic regions were identified in association with ectopic fat in addition to confirming previously known regions. The association of the new regions was specific to ectopic fat, since the majority of the regions were not associated with overall or central adiposity. Furthermore, most of these regions were not associated with type 2 diabetes, lipids, heart disease or blood pressure. The major exception was the region surrounding the UBE2E2 gene, which was associated with diabetes.
MedicalResearch.com Interview with:
Unité UMR 1184 / Centre IMVA
CR1 INSERM, Coordinatrice site Bicêtre
Le Kremlin-Bicêtre Cedex
Medical Research: What is the background for this study? What are the main findings?
Response: Antiretroviral therapy (ART) treatment in HIV infected patients had successfully reduced the development of AIDS (acquired immune deficiency syndrome). However, chronic HIV infection in ART treated patients exhibit rapid uprising of viral load following ART interruption indicating that the virus is not eradicated and persist in some cellular or anatomical sites that are called “reservoir”.
Secondly, ART controlled HIV-infected patients exhibit low grade inflammation developing despite efficient viral control. This low grade inflammation has been associated with non AIDS related pathologies. The aim of our work was to identify site that may combine viral persistence and inflammatory potential. We believed that adipose tissue was a very promising candidate because it included the major targets of HIV infection (CD4 T cells, and macrophages) and exhibited a highly pro-inflammatory potential. Although adipose tissue has been extensively studied as a target of antiretroviral toxicity, we readdress the role of adipose tissue as a reservoir and a site of inflammation. We demonstrated that indeed, adipose tissue from Antiretroviral therapy controlled HIV-infected patients contained infected CD4 T cells that upon in vitro reactivation were able to produce HIV RNA. These results are extremely important because adipose tissue represents 15%-20% of body weight and is diffusely located. We thus identify a large new reservoir.
Medicalresearch.com Interview with:
David T Harris, Phd
Department of Immunobiology
University of Arizona
PO Box 245221, Tucson, AZ 85724.
MedicalResearch.com: What are the main findings of the study?
Dr. Harris: The primary finding of the study was that it was routinely possible to harvest left-over adipose tissue and stem cells from both liposuction and cosmetic procedures, cryopreserve it for prolonged periods of time, and then thaw the tissue later when needed. Frozen and thawed adipose tissue was routinely viable and able to be differentiated into additional fat, as well as bone, cartilage and neuron-like cells. Thus, one can bank adipose tissue and stem cells without first isolating the stem cells allowing one to use the frozen and thawed tissue at later times for both cosmetic applications as well as for regenerative medicine.