Effects of ezetimibe on cholesterol metabolism in HIV-infected patients with protease inhibitor-associated dyslipidemia: a single-arm intervention trial

Effectiveness of ezetimibe in human immunodeficiency virus patients treated for hyperlipidaemia: a systematic review and meta-analysis

OBJECTIVE

Systematic review and meta-analysis of lipid outcomes for human immunodeficiency virus (HIV)-positive or HIV-infected patients treated with ezetimibe.

METHODS

We conducted a literature search from 1946 to 2021 for trials studying the effectiveness of ezetimibe in hyperlipidaemic HIV patients. We included trials of all designs in which HIV patients on highly active antiretroviral therapy (HAART)/non-nucleoside reverse transcriptase inhibitor (NNRTI) therapy had hyperlipidaemia, were treated with ezetimibe, and reported lipid outcomes.

RESULTS

Of thirteen eligible trials, five were randomized controlled trials (RCTs) and eight were single-arm trials. Two of the eligible RCTs were placebo-controlled; we performed a meta-analysis across those two trials for low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride (TG). LDL-C was significantly lower in the ezetimibe arm (net change: -23.56 mg/dL, 95% CI: -40.22, -6.90 mg/dL). We then performed meta-analysis of the single-arm trials examining lipid outcomes after ezetimibe treatment which, like in the RCTs, revealed significant reductions of LDL-C (-23.89 mg/dL, 95% CI -29.94 to -17.83 mg/dL). In addition, significant reductions were seen for total cholesterol (TC) (-26.17 mg/dL, 95% CI -32.81 to -19.54 mg/dL) and TG (-18.57 mg/dL, 95% CI -34.01 to -3.14 mg/dL) but HDL-C did not show a change.

CONCLUSIONS

Evidence for LDL-C reduction is limited in RCTs; single-arm trial LDL-C reductions are consistent with the RCTs. In addition, significant reductions in TC and TG were also seen in the meta-analysis of the single arm trials. The single-arm trials' meta-analysis corroborates evidence from RCTs to suggest that ezetimibe can be an option for hyperlipidaemia among HIV patients with mildly elevated TC and LDL-C levels, especially in cases where statins are contra-indicated due to drug-drug interactions with concomitant anti-retroviral therapy.

Increased cholesterol absorption rather than synthesis is involved in boosted protease inhibitor-associated hypercholesterolaemia

OBJECTIVE

The aim of this study was to compare the differential effects of first-line efavirenz (EFV)-based vs. boosted lopinavir-based antiretroviral regimens on cholesterol metabolism.

DESIGN

Multicentre, open-label, randomized clinical trial.

METHODS

Forty-nine naive HIV-infected patients were randomized (1 : 1) to receive either ritonavir-boosted lopinavir (LPV/r) or EFV both in combination with tenofovir and emtricitabine (ClinicalTrials.gov: NCT00759070). Lipid profile and serum phytosterols and cholesterol precursors were determined at baseline and after 16 weeks.

RESULTS

After 16 weeks of intervention, total and non-HDL cholesterol as well as triglyceride levels significantly increased in the LPV/r-group (+1.0 ± 0.8; +0.8 ± 0.7 and +0.8 ± 1.5 mmol/l, respectively), but not in the EFV-group (+0.4 ± 0.7; +0.4 ± 0.6 and 0.2 ± 0.5 mmol/l, respectively). Markers of cholesterol absorption (campesterol-to-cholesterol and sitosterol-to-cholesterol ratios) significantly increased in the LPV/r-group, but not in the EFV-group, whereas there were no changes in either group of the lathosterol-to-cholesterol ratio, a marker of cholesterol synthesis.

CONCLUSION

Treatment with an LPV/r-based therapy increased total cholesterol relative to EFV-based therapy. Our data suggest that absorption rather than synthesis is the mechanism involved in LPV/r-associated increased total cholesterol.

Hypolipidemic, antioxidant and anti-atherosclerogenic effect of aqueous extract leaves of Cassia. occidentalis Linn (Caesalpiniaceae) in diet-induced hypercholesterolemic rats

BACKGROUND

Hyperlipidemia and oxidative stress are major risk factors for atherosclerosis, and all three are among the most important risk factors for cardiovascular diseases. Cassia occidentalis aqueous extract has been used in African traditional medicine for the treatment of hypertension and associated cardiovascular diseases. This study was undertaken to evaluate the hypolipidemic and anti-atherosclerotic properties of the aqueous extract of the leaves of C. occidentalis in rats with hypercholesterolemia (HC). Sixty Normocholesterolemic (NC) male rats were divided into six groups (n = 10) and fed a high-cholesterol (HC) diet for 30 days (5 groups), or normal rat chow (normal control group). The plant extract was administered to animals at the increasing dose of 240, 320 and 400 mg/kg. After 4 weeks of treatment 5 rats out of 10 were sacrificed, blood samples, aorta, liver, and fresh faecal were collected and processed for biochemical tests. The experiments were conducted under the same conditions with a group of rat treated with Atorvastatin (1 mg/kg), used positive control. The effects of C. occidentalis on weight gain, water and food consumptions, levels of serum lipids and lipoprotein lipid oxidation and stress markers in blood and liver were also examined.

RESULTS

A significant body weight gain was observed in general in all the group of animals without any treatment after 4 weeks. During the treatment period, the C. occidentalis extract induced a significant increase (P < 0.01) in water consumption and food intakes. After 4 weeks of treatment with hypercholesterolemia, the body temperature and organ weights including the liver, kidney, heart and the testis did not present any significant change. The administration of C. occidentalis extract significantly (p < 0.05) prevented the elevation in TC, LDL-C, VLDL-C, hepatic and aortic TG and TC. The atherogenic, triglycerides, and lipid peroxidation (TBARS) index were also decreased in the rats treated with the plant extract. C. occidentalis favoured the performance of faecal cholesterol. It also significantly inhibited the changes and the formation of aortic atherosclerotic plaques.

CONCLUSION

This study provides evidence of hypolipidemic and antiatherosclerotic effects of C. occidentalis extract. C. occidenntalis aqueous extract reduced bad cholesterols, triglycerides and increasing good cholesterols in rats subjected to a feeding regime enriched with cholesterol. The results support the traditional use of the extract of this plant in the treatment of hypertension and diabetes.

Hypolipidemic, antioxidant and anti-atherosclerogenic effects of aqueous extract of Zanthoxylum heitzii stem bark in diet-induced hypercholesterolemic rats

OBJECTIVE

To evaluate anti-dyslipidemic, antioxidant and anti-atherosclerogenic properties of this extract in diet-induced hypercholesterolemic rat, a model of metabolic syndrome-induced atherosclerosis and associated cardiovascular diseases.

METHODS

Normocholesterolemic (NC) male rats were divided into six groups (n=10) and fed a high-cholesterol (HC) diet for 30 days (5 groups), or normal rat chow (normal control group). Rats given a HC diet also received distilled water (disease control), the potent hypocholesterolemic agent with anti-atherosclerotic activity atorvastatin (2 mg/kg, positive control), or one of the three doses of Zanthoxylum heitzii stem bark aqueous extract tested (225, 300 and 375 mg/kg) concomitantly for four months. Signs of general toxicity, body temperature and weight, and water and food intake were monitored in live animals. After sacrifice, lipid profiles and oxidative stress markers were assessed in the blood and liver, aorta, and feces, and histopathological analysis of aorta was performed.

RESULTS

Plant extract prevented the elevation of aortic total cholesterol and triglycerides, and hepatic low density lipoprotein, very low density lipoprotein, and total cholesterol. Lipid peroxidation (TBARS) was decreased and aortic atherosclerotic plaque formation prevented.

CONCLUSIONS

These observations strongly suggest that stem bark aqueous extract of Zanthoxylum heitzii has anti-atherosclerogenic properties, at least partly mediated by antioxidant and hypolipidemic effects.