HIV and Fatigue Mariana Gerschenson, Ph.D. Associate Professor of Medicine Chair of the Cell and Molecular Biology Program John A. Burns School of Medicine

Adults and children estimated to be living with HIV, 2007 Western & Central Europe 730 000 [580 000 – 1.0 million] Eastern Europe & Central Asia 1.5 million [1.1 – 1.9 million] North America 1.2 million [760 000 – 2.0 million] East Asia 740 000 [480 000 – 1.1 million] Middle East & North Africa 380 000 [280 000 – 510 000] Caribbean 230 000 [210 000 – 270 000] South & South-East Asia 4.2 million [3.5 – 5.3 million] Sub-Saharan Africa 22.0 million [20.5 – 23.6 million] Latin America 1.7 million [1.5 – 2.1 million] Oceania 74 000 [66 000 – 93 000] Total: 33 million (30 – 36 million)

Background on Fatigue and HIV HIV+ have prevalence rates of fatigue of up to 98% Fatigue affects the ability to work, interactions with family & friends, unable to manage finances, and needing an entire day for a simple household task Fatigue intensity is higher: duration of HIV, in women, older than age 35, Hispanics, disabled subjects, low income, lack of health insurance, and IV drug use Harmon, J.L. et al, J Assoc Nurses AIDS Care. 2008;19(2):90-7.

HIV Fatigue Tools HIV-Related Fatigue Scale (HRFS)1-Similar to Likert-type 56-item self-report measurements: fatigue intensity and impact of fatigue on daily function, description of fatigue, and triggers of fatigue Sign and Symptom Checklist HIV (SSC-HIVrev)2 This self-report tool on HIV-related signs and symptoms measures the presence and intensity of 72 symptoms, with 1 = mild, 2 = moderate, and 3 = severe. 1. Barrosso J. and Lynn, M.R., Journal of the Association of Nurses in AIDS Care, 13: 66-75 (2002) 2. Holzemer et al., Journal of the Association of Nurses in AIDS Care 12 (5), pp. 60-70 (2001)

HIV Fatigue Etiology Active infection and co-infections with Hep C or OI. Fatigue is not associated with CD4 levels or viral load Anemia Hormonal Imbalances: low testosterone Psychological factors: depression, anxiety Poor nutrition: low Vitamin B12 Sleep and Activity: Efavirenz [Sustiva] can cause nightmares or unusual dreams. Medication Side Effects

Emerging New Landscape of HIV Complications: New factors in the HAART era Potent/Toxic antiretrovirals Alcohol Aging Genetics Chronic “smoldering” immune activation Mitochondrial toxicity HOST HIV EVOLVING CHRONIC COMPLICATIONS Altered Phenotypes-Mitochondrial Fatigue Wasting/Myopathy Lipodystrophy Increased Diabetes/CV Risk Dementia, Peripheral Neuropathy Hepatic-Fatty Liver

Lipoatrophy in 2008 Understanding the mechanism of HIV lipoatrophy continues to be a relevant issue even in the U.S. (where d4T and even ZDV is being utilized less and less) as a recent study utilizing Tenofovir as part of 1st time antiretroviral therapy (A5142) showed that up to 12% of such individuals had limb fat loss of >20% on study* ZDV or d4T are being used in Asia and Africa *Haubrich RH, et al. Metabolic Outcomes of ACTG 5142: A Prospective, Randomized, Phase III Trial of NRTI-, PI-, and NNRTI-sparing Regimens for Initial Treatment of HIV-1 Infection. 14th Conference on Retrovirus and Opportunistic Infections. LA, CA 2007.

Postulated Mechanisms for Body-Fat Abnormatilites by Drug Class NRTIs mtDNA polymerase-g inhibition and mtRNA depletion both lead to Impaired oxidative phosphorylation Altered ATP levels Cell apoptosis Peripheral subcutaneous lipoatrophy with/without visceral fat accumulation → altered WHR PIs (unboosted “older” therapies: IDV, SQV, RTV, APV) Inhibition of Glut4 (by IDV) Insulin resistance Inhibition of transcription factors, eg. PPAR-g, SREBP-1 (by RTV) Cellular apoptosis LPL, ME, and FAS inhibition (by SQV and RTV) Decreased adipocyte differentiation NNRTIs Efavirenz has been shown to suppress lipogenic pathways of adipocytes in vitro PBMC depletion does not correspond with HIV LA (most people do not use this as a marker, usually because there is platelet contamination, which has no nuclei and this alters the numbers) There is a myopathy – original work by Eric Shonn, or Bill Lewis Edward McKees has been working on phosphorylation in mice (ZDV inhibits thymidine phosphorylation in rat heart or liver) We also know that PIs can effect protolytic mitochondrial processes in yeast David Nolan (and here Mallon- slide 15) showed an increase of uncoupling RNA message in pts treated with NRTIs Domingo P et al. AIDS. 1999 13(16):2261-7 - Subcutaneous adipocyte apoptosis occurs in lipoatrophic areas of patients with HIV-1 protease inhibitor- associated lipodystrophy Carr A, et al. AIDS. 2000;14:F25-32; McComsey GA, et al. AIDS. 2005;19:15–23; Domingo P, et al. AIDS. 1999;13:2261–67; Mynarcik D, et al. J AIDS. 2005;38:53–56; Walker UA, et al. J AIDS. 2002;29:117–21; Roche R, et al. AIDS. 2002;16;13–20; Vernochet C, et al. AIDS. 2003;17:2177–80. Domingo P, et al. AIDS. 1999 13(16):2261-7.

Development of Metabolic Disease in HIV Patients Lipodystrophy Visceral Adiposity Fat depletion Elevated plasma FFA Increased Intramyocellular/ Intrahepatic Fat INSULIN RESISTANCE Genetic Predisposition Impaired Mitochondrial Activity Direct PI Effect GLUT4 Insulin-resistance-mediated failure to suppress lipolysis NRTI-mediated Mitochondrial toxicity in muscle Hepatic steatosis Chronic Inflammatory Changes induced by HIV Cytokine dysregulation Age-related increase In Insulin Resistance Shikuma, CM, Day L, Gerschenson, M. Current Drug Targets-Infectious Disorders, 2005.

Mitochondria and Macrophages in HIV Lipoatrophy Model BLOOD Monocytes HIV virus HIV-infected and non-infected, activated monocytes secreting cytokines NRTIs Infiltrating activated macrophages FAT Mitochondrial and cellular dysfunction induced by NRTIs Pre-adipocytes and adipocytes Macrophage-induced amplification of inflammation and cellular damage 1 2 3 4

Mitochondrial DNA Polymerase-γ Hypothesis The mitochondrial DNA polymerase-γ is the principal polymerase required for mitochondrial DNA replication Susceptible to inhibition by NRTIs Inhibition can lead to mtDNA depletion NRTI Phosphorylation NRTI-TP DNA Pol-g mtDNA Abundance mtDNA mtDNA Oxidation Antioxidant Defenses OXPHOS The mitochondrial DNA polymerase gamma is the principal polymerase required for mitochondrial DNA replication Susceptible to inhibition by NRTIs Inhibition can lead to mtDNA depletion “Mitochondrial DNA polymerase- appears much more susceptible to inhibition by nucleoside and nucleotide analogue antiretrovirals.”1 “The DNA pol-gamma hypothesis states that inhibition of mtDNA replication by NRTIs leads to mitochondrial dysfunction. This is accomplished via mtDNA depletion and structural alterations to the mitochondrial genome, which encodes many of the components necessary for aerobic metabolism through oxidative phosphorylation (OXPHOS).”2 1. Kakuda TN. Clin Ther. 2000; 22:685–708. 2. Day L et al. Mitochondrion. 2004; 4:95–109. Energetics ROS Cell Dysfunction Velsor LW. Toxicol Appl Pharmacol. 2004;99:10-19.

Hypothesis: Potential Consequences of Mitochondrial Dysfunction ART HIV HIV Cytokines Metabolic Disease (LD, IR,  TGs) DNA polymerase-g Uncoupling Transport Oxidative Stress Apoptosis Phosphorylation Proteolytic Processing Glycosylation Lipodystrophy Increased lactate correlates with impaired mitochondrial function1,2 Mitochondrial derived lipid oxidative markers (ROS) are significantly increased in lipoatrophy3 IR can be cause by LD, or Hepatic steatosis The measurement of lactate, which is increased in NRTIs patients, is the hallmark of mitochondrial complications. “Long-term complications of ART are increasingly recognized as significant causes of morbidity and mortality. Many of these complications are thought to be mediated through mitochondrial injury, which appears to be the result of nucleoside analogue toxicity…. A syndrome of fatty liver (steatosis) with lactic acidosis represents the most fulminant presentation of such antiretroviral toxicity… However, lactate elevations are not a component of NAFLD, suggesting other factors must also be involved.” 1 “Hyperlactatemia and lactic acidosis have been observed in HIV-infected patients receiving antiretroviral therapy. The spectrum of disease ranges from mild to moderate asymptomatic (or sub-clinical) hyperlactatemia to fulminate and life threatening lactic acidosis. Evidence suggests that exposure to one or more NRTIs plays a central role through toxic effects on mitochondrial function… In addition to inhibiting HIV reverse transcriptase, NRTIs inhibit mitochondrial DNA polymerase γ, an essential enzyme in the replication process of mtDNA. Inhibition of this enzyme depletes mtDNA and impairs mitochondrial function. In vitro studies using NRTI-exposed human T-lymphoblastoid cell lines have demonstrated a rapid toxic effect on drug- exposed cells, leading to depletion of mtDNA, morphologic changes in mitochondria, and increased production of lactic acid. These effects appear to be dose dependent.“2 1. Day L, et al. Mitochondrion. 2004;4:95–109. 2. AACTG Metabolic Guides: http://aactg.s-3.com/metabolic/lactic.pdf. 3. McComsey GA, Morrow JD. J Acquir Immune Defic Syndr. 2003;34:45-9. Neuropathies Hepatic Steatosis Myopathy Pancreatitis Lactic Acidosis Day L, et al. Mitochondrion. 2004;4:95–109. AACTG Metabolic Guides: http://aactg.s-3.com/metabolic/lactic.pdf. McComsey GA, Morrow JD. J Acquir Immune Defic Syndr. 2003;34:45-9. Dagan T, Sable C, Bray J, Gerschenson M. Mitochondrion. 2002;1:397-412. Gerschenson, M. and Brinkman, K. Mitochondrion. 2004;4(5-6):763-777.

Talk Summary Fatigue is common in HIV+ patients Fatigue is associated with HIV complications e.g. lipoatrophy HIV lipoatrophy has a mitochondrial etiology; mtDNA, mtRNA, OXPHOS, and ATP levels are altered in subcutaneous fat. Mitochondrial OXPHOS in PBMCs correlates with subcutaneous fat OXPHOS

HIV as a Model for Fatigue Metabolic syndrome: hypertension, hyperlipidemia, and insulin resistance Increase in cytokines: TNF-, IL-6, MCP-1, IL-1 Human tissue or cell specific studies to understand pathogenesis Minimally invasive systemic biomarker(s) to correlate with prevention, diagnosis, and progression

References for HIV and Fatigue Harmon, J.L. et al, Demographic and illness-related variables associated with HIV-related fatigue, J Assoc Nurses AIDS Care. 2008;19(2):90-7. Shikuma, CM, Day L, Gerschenson, M. Insulin resistance in the HIV-infected population: the potential role of mitochondrial dysfunction.Current Drug Targets-Infectious Disorders, 2005. Gerschenson M, Brinkman K., Mitochondrial dysfunction in AIDS and its treatment. Mitochondrion. 2004 Sep;4(5-6):763-77. Epub 2004 Sep 25. Highleyman,L. A Comprehensive Look at HIV-Related Fatigue,, 2001, http://www.thebody.com/content/treat/art2640.html.