Alterations of apolipoprotein B metabolism in HIV-infected patients with antiretroviral combination therapy

BACKGROUND: Dyslipidemia (predominantly hypertriglyceridemia) is frequently seen in patients receiving antiretroviral combination therapy (ART). However, the underlying mechanisms and long-term risks (e.g., cardiovascular events) are still unclear. OBJECTIVES/METHODS: In 5 patients with ART-associated dyslipidemia, stable isotope labeled amino acid tracer (d3-Leu) kinetic analysis over 12 days was used to investigate the metabolism of apolipoprotein B-containing lipoproteins (very low density lipoproteins [VLDL]1, VLDL2, intermediate density lipoproteins [IDL] and low density lipoproteins [LDL]). Data were compared with those in 6 healthy normolipidemic controls. RESULTS: The patients under ART showed significantly increased fasting triglycerides (359 vs. 77 mg/dl) and VLDL (54 vs. 15 mg/dl), compared with controls. They had significantly higher total cholesterol (213 vs. 157 mg/dl) and there was a nonsignificant trend toward higher LDL (136 vs. 93 mg/dl), and toward lower HDL (26 vs. 46 mg/dl). The ratio of large, buoyant LDL1 over small, dense LDL2 was markedly reduced in patients under ART (0.80 vs. 2.00). Total apo B synthesis was significantly increased (25.5 vs. 14.5 mg/kg/d) and shifted toward triglyceride rich VLDL1 (18.5 vs. 8.7 mg/kg/d) in patients receiving ART. There was also a significantly reduced rate of apo B lipoprotein transfer from VLDL1 to VLDL2 (3.7 vs. 20.7 pools/d). In addition, all patients revealed insulin resistance. CONCLUSIONS: These data indicate that increased triglycerides in HIV-infected patients with ART are primary due to reduced rates of VLDL transfer into denser lipoproteins implying a lower rate of lipoprotein lipase-mediated delipidation. In addition, total apo B synthesis was increased and shifted toward triglyceride-rich VLDL1. Overall, this lipoprotein profile in patients with ART-associated dyslipidemia implies an increased risk for cardiovascular events.     

Hepatotoxicity development during antiretroviral therapy containing protease inhibitors in patients with HIV: the role of hepatitis B and C virus infection.

To evaluate the occurrence of hepatotoxicity in patients during antiretroviral therapy (ART) that contains protease inhibitors and the role of hepatitis viruses in its development, we performed a retrospective study including 1325 HIV-infected patients treated with ART for at least 6 months. Presence or absence of hepatitis viruses, alanine aminotransferase (ALT), total bilirubin, CD4 cell count, and plasma HIV RNA levels were evaluated. Hepatotoxicity developed in a few study subjects without coinfection, whereas it was significantly higher in coinfected patients. Univariate logistic regression analysis showed that viral hepatitis coinfections are independent risk factors for hepatotoxicity. After 6 months of treatment, ritonavir was associated with higher rates of severe hepatotoxicity in the coinfected group; in fact, ritonavir seems to be the most strongly hepatotoxic agent among coinfected patients. After 12 months of therapy, hepatotoxicity occurred more frequently in patients with hepatitis C virus who did not respond to antiretroviral therapy (ART), whereas patients who did respond to ART showed decreased ALT levels. Hepatotoxicity is not exclusively an effect of drug toxicity, and the presence of hepatitis coinfection is an independent risk factor. Moreover, chronic hepatotoxicity mainly occurs in patients who did not respond to therapy. Conversely, patients who did respond to ART seemed to show improvement of chronic liver infection.     

HIV and antiretroviral therapy: lipid abnormalities and associated cardiovascular risk in HIV-infected patients

It has been demonstrated that patients on highly active antiretroviral therapy are at increased risk for developing metabolic abnormalities that include elevated levels of serum triglycerides and low-density lipoprotein cholesterol and reduced levels of high-density lipoprotein cholesterol. This dyslipidemia is similar to that seen in the metabolic syndrome, raising the concern that highly active antiretroviral therapy also potentially increases the risk for cardiovascular complications. This paper reviews the contribution of both HIV infection and the different components of highly active antiretroviral therapy to dyslipidemia and the role of these abnormalities toward increasing the risk of cardiovascular disease in HIV-infected patients; therapeutic strategies to manage these risks are also considered.     

复方环丙孕酮联合胰岛素增敏剂对非肥胖多囊卵巢综合征伴有胰岛素抵抗患者治疗效果的观察

目的探讨比较单独应用复方环丙孕酮（CPA）与CPA联合胰岛素增敏剂治疗非肥胖多囊卵巢综合征（P-COS）伴有胰岛素抵抗患者治疗效果的差异,以及二甲双胍和罗格列酮两种胰岛素增敏剂对于上述患者治疗效果的差异。方法68例非肥胖PCOS合并胰岛素抵抗（IR）患者随机分成3组,A组26例,单独应用CPA3个周期;B组23例。应用CPA＋MTE治疗3个周期;C组19例,应用CPA＋罗格列酮治疗3个周期。采取自身对照及组间对照法,比较用药前后血清胰岛素水平、IR指数、体重指数（BMI）、性激素等指标的差异。结果3组病人治疗后T及LH／FSH均较治疗前明显降低,B组、C组病人空腹胰岛素,IR指数等显著改善,B组、C组之间上述指标无显著差异。结论非肥胖型PCOS伴有IR患者应用胰岛素增敏剂,可以明显改善内分泌、代谢紊乱,二甲双胍与罗格列酮比较无显著差异。     

Pneumocystis carinii pneumonia recurrence in HIV patients on highly active antiretroviral therapy: secondary prophylaxis

The incidence and risk factors for Pneumocystis carinii pneumonia (PCP) recurrence were evaluated in 451 HIV-infected patients enrolled in the French Hospital Database on HIV who started highly active antiretroviral therapy (HAART) while receiving secondary PCP prophylaxis after a first episode occurring between January 1995 and December 1998. There were 18 episodes of recurrent PCP. On HAART, the CD4+ cell count increased to above 200 x 106/L in 274 patients, 51 of whom stopped PCP prophylaxis. None of these patients had PCP recurrences during 363 person-years (PY) of follow-up after the CD4+ cell count had reached 200 x 106/L (incidence rate [IR], 0.00 cases/100 PY; 95% confidence interval [CI], 0.00-0.82), and 37 PY of follow-up after the CD4+ cell count had reached 200 x 106/L and PCP prophylaxis had been discontinued (IR, 0.00 cases/100 PY; 95% CI, 0.00-7.84). The CD4+ cell count remained < 200 x 106/L in 177 patients; 9 patients stopped PCP prophylaxis, and 6 of these had a disease recurrence. Multivariate Cox analysis (time censored when CD4+ cell count > 200 x 106/L) showed that discontinuation of secondary prophylaxis (relative hazard [RH], 25.95; p <.0001) was associated with recurrence, whereas higher CD4+ cell counts during follow-up (RH, 0.39/50 x 106/L increment; p <.002) were protective.     

Adverse effects of antiretroviral therapy on liver hepatocytes and endothelium in HIV patients: An ultrastructural perspective

Human immunodeficiency virus and antiretroviral therapy (ART) together can be far more detrimental to liver cells than either of the two unaided. However, ultrastructural aspects of the synergistic effects of HIV and ART have been understudied. In a patient cohort receiving ART, this study characterizes ultrastructurally sinusoidal degeneration, hepatocytic aberrations, mitochondrial dysfunction, accumulation of bulky lipid droplets (steatosis), and occlusion of sinusoidal lumina. Mitochondrial dysfunction causes the accumulation of acetyl-CoA which leads to insulin upregulation and resistance, lipid synthesis, and steatosis. Lipid droplets deposited in the sinusoids could be the source of the blood’s lipid profile alterations in HIV patients on ART.     

Replication capacity,biological phenotype,and drug resistance of HIV strains isolated from patients failing antiretroviral therapy

The fitness of human immunodeficiency virus (HIV) in vivo depends on the interaction of a multitude of viral and host factors. The aim of this study was to analyze the biological phenotype and the intrinsic capacity of the HIV isolates with drug-resistance mutations to replicate efficiently in the absence of drugs. An open label multicenter cross-sectional study was undertaken on 28 HIV-infected patients failing antiretroviral treatment. The subjects were studied for CD4+ cell count, HIV viral load, syncytium-inducing phenotype, genotypic drug-resistance assay, and replication capacity of HIV isolates assessed by co-culture assay. All HIV isolates showed a decreased replication capacity compared with wild-type strains. The lowest replication capacity was detected in HIV strains with more than five drug-resistance mutations. The highest replication capacity was observed in strains carrying the K103N and Y181C primary mutations that emerged after treatment with non-nucleoside analogue inhibitors. Isolates with R5 biological phenotype had a higher number of resistant mutations than X4 isolates (P = 0.004). Particularly, the R5 phenotype was detected in all 6 isolates with more than 14 drug-resistance mutations. Patients with R5 strains had plasma viral load similar to patients with X4 strains, but marginally higher CD4+ cell counts, and their HIV isolates had significantly lower replication capacity of HIV isolates (P = 0.008). No patient carrying HIV with a maintained replication capacity had a viral load less than 30,000 copies/ml. In patients failing HAART, the detection of HIV isolates with the R5 biological phenotype correlates with CD4+ cell count, an impaired replication capacity, and a high number of drug-resistance mutations.     

Association between insulin resistance and hepatitis C virus chronic infection in HIV-hepatitis C virus-coinfected patients undergoing antiretroviral therapy.

Insulin resistance (IR) in the context of highly active antiretroviral therapy (HAART) is becoming more common in HIV-infected patients. Patients with chronic hepatitis C virus (HCV) infection have an increased risk of IR and type 2 diabetes mellitus. A cross-sectional study was performed to investigate whether chronic HCV infection constitutes a risk factor for IR in HIV-HCV-coinfected patients undergoing HAART. Inclusion criteria were positive HCV viremia and a sustained increase of alanine aminotransferase of at least twice the normal value. A total of 29 HIV-HCV patients, 76 HIV patients, and 121 HCV controls were tested for IR and body mass index (BMI). IR was measured using the homeostasis model assessment. In HIV-HCV and HIV patients, fat redistribution and lipid profile were assessed. There was no significant difference in age, CD4 cell count, HIV viral load, or duration of HAART between the HIV-HCV and HIV groups. HIV-HCV patients and HCV controls had a significant increase in IR when compared with HIV patients (0.25 +/- 0.28 and 0.21 +/- 0.34 versus 0.04 +/- 0.37; p =.01 and p =.003, respectively). Lipoatrophy was observed more frequently in HIV-HCV patients in comparison with HIV patients (41% versus 14%; p =.003). In HIV-HCV patients, total cholesterol and triglyceride levels were significantly lower than in HIV patients. In multivariate analysis, IR, BMI, triglyceride levels, and peripheral fat wasting were the independent variables associated with HCV infection. Our findings suggest that chronic HCV infection is a significant factor associated with the development of metabolic abnormalities and with modifications in body composition in HIV patients receiving antiretroviral treatment.