The Effect of Substrate Supply on Modulating Plasma GSH Levels in Treated HIV+ Patients

Among the 4 sulphur-containing amino acids (SAA), only Met and Cys are incorporated into proteins, but Hcy and Tau are related to oxidative stress and glutathione (GSH), the major intracellular hydro-soluble anti-oxidant agent. HIV+ patients present low levels of antioxidant nutrients, including GSH and its precursors.

To investigate the responses of the SAA pathway to dietary supplements of Gln and Cys together with Met-overloading in HIV+ patients comparatively to healthy controls.

Methods: Twelve HIV+ (6 males and 6 females, 25-36 yrs old) patients under HAART (one HIV protease inhibitor in combination with two nucleoside analogs) for at least one year and 20 (10M and 10F, 23-28 yrs old) healthy controls were randomly assigned to 7-day diets containing either NAC (N-acetylcysteine, 1g/d) or Gln (20g/d), with a 7-day washout period with their usual diet (UD). Blood samples were drawn after overnight fast before and after (2h and 4h) ingesting the Met (100 mg/kg) overload (Met-OL) with determination of the area under the curve (AUC). HPLC plasma analysis of SAA (Met, Hcy, Cys and Tau), GSH and GSSG and Ser, Gly, Glu and Gln was carried out at moments before (MO) and after 7-day diets (M1). Additionally, at baseline, both groups were assessed for anthropometry (BMI, kg/m2; body fat %) and plasma biochemistry (creatinine, urea, γ-glutamyl transpeptidase, glucose, triglycerides, cholesterol, uric acid, albumin, folic acid and vitamin B12).The HIV+ group (G2) was also characterized by the viral load, CD4+ and CD8+ lymphocytes counts. Statistical comparisons were undertaken among diets between groups with p = 0.05.