title: Whole body leucine flux in HIV-infected patients treated with or without protease inhibitors.
abstract: The present study was carried out to assess the effects of protease inhibitor (PI) therapy on basal whole body protein metabolism and its response to acute amino acid-glucose infusion in 14 human immunodeficiency virus (HIV)-infected patients. Patients treated with PIs (PI+, 7 patients) or without PIs (PI-, 7 patients) were studied after an overnight fast during a 180-min basal period followed by a 140-min period of amino acid-glucose infusion. Protein metabolism was investigated by a primed constant infusion of l-[1-(13)C]leucine. Dual-energy X-ray absorptiometry for determination of fat-free mass (FFM) and body fat mass measured body composition. In the postabsorptive state, whole body leucine balance was 2.5 times (P < 0.05) less negative in the PI+ than in the PI- group. In HIV-infected patients treated with PIs, the oxidative leucine disposal during an acute amino acid-glucose infusion was lower (0.58 +/- 0.09 vs. 0.81 +/- 0.07 micromol x kg FFM(-1) x min(-1) using plasma [(13)C]leucine enrichment, P = 0.06; or 0.70 +/- 0.10 vs. 0.99 +/- 0.08 micromol x kg FFM(-1) x min(-1) using plasma [(13)C]ketoisocaproic acid enrichment, P = 0.04 in PI+ and PI- groups, respectively) than in patients treated without PIs. Consequently, whole body nonoxidative leucine disposal (an index of protein synthesis) and leucine balance (0.50 +/- 0.10 vs. 0.18 +/- 0.06 micromol x kg FFM x (-1) x min(-1) in PI+ and PI- groups respectively, P < 0.05) were significantly improved during amino acid-glucose infusion in patients treated with PIs. However, whereas the response of whole body protein anabolism to an amino acid-glucose infusion was increased in HIV-infected patients treated with PIs, any improvement in lean body mass was detected.
authors.affiliation: Unité de Nutrition et Métabolisme Protéique, Institut National de la Recherche Agronomique, Clermont-Ferrand/Theix, Saint-Genès-Champanelle, France.
authors.forename: Magali
authors.initials: M
authors.lastname: Prod'homme
authors.forename: Cécile
authors.initials: C
authors.lastname: Rochon
authors.forename: Michèle
authors.initials: M
authors.lastname: Balage
authors.forename: Henri
authors.initials: H
authors.lastname: Laurichesse
authors.forename: Igor
authors.initials: I
authors.lastname: Tauveron
authors.forename: Claude
authors.initials: C
authors.lastname: Champredon
authors.forename: Philippe
authors.initials: P
authors.lastname: Thieblot
authors.forename: Jean
authors.initials: J
authors.lastname: Beytout
authors.forename: Jean
authors.initials: J
authors.lastname: Grizard
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D001823:Body Composition / Q000502:physiology; D002245:Carbon Dioxide / Q000378:metabolism; D005947:Glucose / Q000008:administration & dosage / Q000378:metabolism; D006678:HIV; D015658:HIV Infections / Q000188:drug therapy* / Q000378:metabolism*; D017320:HIV Protease Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D007930:Leucine / Q000008:administration & dosage / Q000097:blood / Q000378:metabolism* / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged
chemical_list: D017320:HIV Protease Inhibitors; D002245:Carbon Dioxide; D007930:Leucine; D005947:Glucose