Effects of L-Carnitine on Postprandial Clearance of Triglyceride-rich Lipoproteins in HIV Patients on HAART
Condition: Hyperlipidemia; HIV Infections
MeSH terms: Hyperlipidemias
Study type: Interventional

Summary: 
      Included in this study will be patients with HIV and being treated with highly active
      antiretroviral medications (HAART) including protease inhibitors (PI) or non-nucleoside
      reverse transcriptase inhibitors (NNRTI). Protease inhibitors and non-nucleoside reverse
      transcriptase inhibitors are very common medications in HIV treatment and are usually given
      with other medications as part of a standard treatment for HIV (HAART).

      We hope to learn more about how the levels of cholesterol-and triglyceride-carrying particles
      (lipoproteins) are affected by a nutritional supplement, L-Carnitine, in HIV-positive
      patients treated with antiretroviral medications.
    

Detailed description: 
      The postprandial state is a proinflammatory and proatherogenic condition. Increasing evidence
      support the contention the elevated triglyceride (TG)-rich lipoproteins (TGRL) are
      atherogenic. Hypertriglyceridemia is a characteristic of the metabolic complications during
      human immunodeficiency virus/highly active antiretroviral therapy (HIV/HAART) and the
      increased postprandial lipemia commonly seen in this situation may convey an increased
      cardiovascular risk. A possible contribution to the hypertriglyceridemia in HIV/HAART may be
      a decrease in mitochondrial function, resulting in a decreased fatty acid oxidation. A
      decrease in mitochondrial function may also contribute to insulin resistance. L- Carnitine
      plays an important role in the transfer of long-chain acyl groups into the mitochondrial
      matrix and potentially improves energy metabolism. L- Carnitine has been shown to reduce
      hypertriglyceridemia during HAART in HIV-positive subjects, but virtually nothing is known
      about its effect in the postprandial state. We have experience from postprandial studies in
      HAART-treated HIV-positive African American and Hispanic subjects, where we have focused on
      the relationship between lipids, fatty acids, insulin and adipokines. This is of particular
      relevance among African Americans, where key metabolic components differ substantially from
      levels in Caucasians. Further, the relationship between metabolic parameters and HIV/HAART is
      far less explored in this ethnic group. We recently found a proportional relationship between
      insulin and non-esterified fatty acids (NEFA) in response to food among African American
      HIV-positive subjects. Further, we showed a relationship between fasting insulin and
      postprandial adipokine levels.

      In this randomized, double blind placebo-controlled pilot study, we will explore whether L-
      Carnitine affects TGRL metabolism in the fasting and the postprandial states among African
      American and Hispanic HIV-positive subjects undergoing antiretroviral therapy.

      We hypothesize: (1) that L- Carnitine supplementation will improve both fasting TGRL levels
      and the postprandial response, and (2) that L- Carnitine will impact on the relationship
      between insulin and NEFA or adipokines in the postprandial state.

      In our specific aims, we will test the effect of L- Carnitine supplementation on:

        -  Baseline TGRL metabolism and insulin, NEFA and adipokine levels

        -  Postprandial TGRL responses and the postprandial relationship between insulin and
           non-esterified fatty acids (NEFA) and adipokines We believe that the results generated
           from the proposed studies will help to evaluate effects of L- Carnitine supplementation
           on postprandial TGRL-associated cardiovascular risks.
    

Intervention name(s): L-carnitine; placebo
Intervention type(s): Dietary Supplement; Other
Intervention description(s): 3 grams daily in liquid form by mouth; 1 oz sweet tasting liquid daily by mouth
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: L-carnitine; HIV; TGRL metabolism; postprandial; HIV Treatment Experienced