Lipodystrophy: results of a data evaluation of patients receiving nelfinavir-containing combination therapy

Nelfinavir: a review of its use in the management of HIV infection

Nelfinavir (Viracept) is an orally administered protease inhibitor. In combination with other antiretroviral drugs (usually nucleoside reverse transcriptase inhibitors [NRTIs]), nelfinavir produces substantial and sustained reductions in viral load in patients with HIV infection. Nelfinavir may be used in the treatment of adults, adolescents and children aged >or=2 years with HIV infection. It can also be used in pregnancy. Resistance to nelfinavir may develop, but the most common mutation (D30N, appearing mainly in HIV-1 subtype B) does not confer resistance to other protease inhibitors, thereby conserving these agents for later use. Although less effective than lopinavir/ritonavir, the preferred first-line treatment in US guidelines, nelfinavir is positioned as an alternative agent for the treatment of adults and adolescents with HIV infection and is an option for those unable to tolerate other protease inhibitors. Nelfinavir also has a role in the management of pregnant patients as well as paediatric patients with HIV infection.

HIV antiretroviral agents inhibit protein synthesis and decrease ribosomal protein S6 and 4EBP1 phosphorylation in C2C12 myocytes

Combined antiretroviral drug regimens have promoted clinical, immunologic, and virologic improvements in AIDS patients. Nevertheless, these therapies are associated with derangements in lipid and carbohydrate metabolism. In this study, we examined the effects of a representative protease inhibitor (nelfinavir), a nonnucleoside reverse transcriptase inhibitor (nevirapine), and a nucleoside reverse transcriptase inhibitor (zidovudine) on protein synthesis in skeletal muscle cells. To examine these processes, C2C12 myocytes were treated with increasing concentrations of nelfinavir, nevirapine, or zidovudine for 1 or 2 days, and rates of protein synthesis were determined by measuring [35S]methionine/cysteine incorporation into cellular proteins. Treatment of myocytes with therapeutic concentrations of nelfinavir, nevirapine, or zidovudine for 48 hr decreased protein synthesis by 14-20%. An approximately 60% decline was observed in cells treated with higher concentrations of nevirapine or nelfinavir. In contrast, the basal rate of protein synthesis was not affected when cells were incubated with these compounds for 24 hr. Therapeutic concentrations of nelfinavir and nevirapine did not impair the anabolic effect of insulin on protein synthesis. However, zidovudine suppressed the stimulatory effect of insulin. The decreased protein synthesis induced by nelfinavir and zidovudine was associated with decreases in the phosphorylation of the S6 ribosomal protein (rpS6) and the repressor binding protein 4EBP1, while the inhibitory effect of nevirapine was mainly associated with a decline in phosphorylated 4EBP1. In conclusion, nelfinavir, nevirapine, and zidovudine treatments decreased protein synthesis in myocytes and this effect was correlated with a reduction in the phosphorylation level of proteins that regulate translation initiation.

Prevalence of, evolution of, and risk factors for fat atrophy and fat deposition in a cohort of HIV-infected men and women

BACKGROUND

At present, no uniform definition of human immunodeficiency virus (HIV)-associated lipoatrophy exists. The risk factors for fat atrophy (FA) and central fat deposition (FD) are multifactorial. We assessed the evolution and predictors of FA and FD in HIV-infected men and women.

METHODS

Participants (n = 452) were evaluated at baseline (starting in November 1998) and 1 year later. FA was defined as triceps skin-fold measurement less than the 10th percentile on the National Health and Nutrition Examination Survey for sex and age. FD was defined as a waist-to-hip ratio of > 0.95 for men and of > 0.85 for women. Predictors of the baseline prevalence of FA and FD and new cases of each syndrome after 1 year were determined.

RESULTS

The baseline prevalences of FA, FD, and combined FA and FD were 35%, 44%, and 14%, respectively. Twenty-two percent of subjects had newly developed FA at 1 year, and 16% of subjects with FA at baseline did not have it at 1 year. Also, 23% of subjects had newly developed FD at 1 year, and 15% of those with FD at baseline did not have it at 1 year. The risk of developing new FA was increased among participants with low triceps skin-fold values (P < .001), smaller hips (P < .001), higher nadir HIV load (P = .006), abacavir use (P < .001), stavudine use (P < .001), and use of highly active antiretroviral therapy (P = .002). The risk of developing new FD was higher among women (P < .001) and among participants with greater body fat levels (P = .005) and higher triglyceride levels (P < .001), and it was lower among those with a high school education (P = .003) and higher triceps skin-fold values (P = .026).

CONCLUSIONS

FA and FD are common in HIV-infected patients, but may change over time in the individual. FA and FD appear to be different syndromes, because risk factors for the development differ, and the prevalence of the combined syndrome differs from the prevalences of the 2 independent syndromes.