1.
L-Carnitine's Effect on the Biomarkers of Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Choi, M, Park, S, Lee, M
Nutrients. 2020;(9)
Abstract
A systematic review and meta-analysis of randomized controlled trials (RCTs) was carried out to assess L-carnitine supplements' influence on the biomarkers of metabolic syndrome (MetSyn). PubMed, EMBASE, Cochrane library, and CINAHL were used to collect RCT studies published prior to February 2020. RCT studies were included if they had at least one of the following biomarker outcome measurements: waist circumference (WC), blood pressure (BP), fasting blood sugar (FBS), triglyceride (TG), or high density lipoprotein-cholesterol (HDLc). Nine of twenty studies with adequate methodological quality were included in this meta-analysis. The dose of L-carnitine supplementation administered varied between 0.75 and 3 g/day for durations of 8-24 weeks. L-carnitine supplementation significantly reduced WC and systolic BP (SBP), with no significant effects on FBS, TG, and HDLc. We found that L-carnitine supplementation at a dose of more than 1 g/d significantly reduced FBS and TG and increased HDLc. In conclusion, L-carnitine supplementation is correlated with a significant reduction of WC and BP. A dose of 1-3 g/d could improve the biomarkers of MetSyn by reducing FBS and TG and increasing HDLc.
2.
Randomized controlled trial of N-acetylcysteine versus l-carnitine among women with clomiphene-citrate-resistant polycystic ovary syndrome.
El Sharkwy, IA, Abd El Aziz, WM
International journal of gynaecology and obstetrics: the official organ of the International Federation of Gynaecology and Obstetrics. 2019;(1):59-64
Abstract
OBJECTIVE To compare clinical and metabolic profiles between N-acetylcysteine and l-carnitine among women with clomiphene citrate (CC)-resistant polycystic ovary syndrome (PCOS). METHODS A randomized trial at Zagazig University between January 2017 and March 2018. Women with CC-resistant PCOS were allocated randomly to receive CC plus N-acetylcysteine or CC plus l-carnitine. The primary outcome was clinical pregnancy rate; secondary outcomes were ovulation rate and metabolic changes. RESULTS Overall, 162 women completed the study (N-acetylcysteine group, n=82; l-carnitine group, n=80). After 3 months, there was no difference in pregnancy (P=0.15), ovulation (P=0.21), or spontaneous abortion (P=0.11) rates between the two groups. There was no significant decrease in BMI in either group (both P>0.05). There were improvements in menstrual pattern, follicle-stimulating hormone, luteinizing hormone, free testosterone, and insulin resistance markers in both groups (all P<0.05). An improvement in lipid profile was observed only in the l-carnitine group (P<0.001). N-Acetylcysteine treatment led to significantly greater improvement in free testosterone and insulin resistance parameters as compared with l-carnitine (all P<0.05). CONCLUSIONS Both N-acetylcysteine and l-carnitine were equally effective in improving pregnancy and ovulation rates among women with CC-resistant PCOS. However, N-acetylcysteine was superior in ameliorating insulin resistance and only l-carnitine improved lipid profile. TRIAL REGISTRATION ClinicalTrials.gov: NCT03164421.