Mitochondrial Oxidative Phosphorylation Protein Levels in Peripheral Blood Mononuclear Cells Correlate with Levels in Subcutaneous Adipose Tissue within Samples Differing by HIV and Lipoatrophy Status

Abstract

Depletion of mitochondrial DNA (mtDNA) and mtDNA-encoded respiratory chain proteins in subcutaneous (SC) fat from patients with HIV lipoatrophy have clearly demonstrated the role of mitochondrial dysfunction in this syndrome. Research in HIV lipoatrophy, however, has been severely hampered by the lack of a suitable surrogate marker in blood or other easily obtained clinical specimens as fat biopsies are invasive and mtDNA levels in peripheral blood mononuclear cells (PBMC) do not consistently correlate with the disease process. We used a simple, rapid, quantitative 2-site dipstick immunoassay to measure OXPHOS enzymes Complex I (CI) and Complex IV (CIV), and rtPCR to measure mtDNA in 26 matched SC fat and PBMC specimens previously banked from individuals on potent antiretroviral (ARV) therapy with HIV lipoatrophy, on similar ARV therapy without lipoatrophy, and in HIV seronegative controls. Significant correlations were found between the respective PBMC and fat levels for both CI (r ϭ 0.442, p ϭ 0.024) and for CIV (r ϭ 0.507, p ϭ 0.008). Both CI and CIV protein levels were also significantly reduced in both PBMCs and fat in lipoatrophic subjects compared to HIV seronegative controls (p Յ 0.05), while a comparative reduction in mtDNA levels in lipoatrophic subjects was observed only in fat. We conclude that CI and CIV levels in PBMCs correlate to their respective levels in fat and may have utility as surrogate markers of mitochondrial dysfunction in lipoatrophy. 1255

Impaired mitochondrial function is abrogated by dexrazoxane in doxorubicin‐treated childhood acute lymphoblastic leukemia survivors

“…In this study, after a median of 7 years since the completion of doxorubicin treatment, survivors of childhood high‐risk ALL treated with doxorubicin alone had 3 times the number of mtDNA copies per cell in PBMCs in comparison with children treated with doxorubicin plus dexrazoxane, but OXPHOS enzyme activities did not differ between the groups. In addition, mtDNA copies per cell in those who received dexrazoxane were within the normal ranges observed in our previous studies (100‐350 copies per cell) …”

Relationship of Oxidative Stress with HIV Disease Progression in HIV/HCV Co-infected and HIV Mono-infected Adults in Miami

“…The extracted DNA was subjected to determination of concentration by a spectrophotometric method and securely stored at −20°C until use. Total protein was extracted from PBMCs of 3.0~5.5 × 10 6 cells according to the method described elsewhere [38]. The purified protein was undergone for estimation of concentration using BCA protein assay kit (Pierce Technology) and stored at −20°C for future application after appropriate concentration determined.…”

Mitochondrial damage in adipose tissue of untreated HIV-infected patients

“…Classical studies have blamed NRTI therapies of mtDNA depletion and mitochondrial dysfunction found in adipose tissue of lipodystrophy [16][17][18][19][20][21] or nonlipodystrophy HIV patients [22][23][24][25][26]. However, the role of HIV in mitochondrial adipose tissue lesion is still a matter of doubt [10].…”