Uusitupa, B vitamins for vegetarians University, Kuopio, Finland; Anc. Efficacy maangement l-carnitine supplementation for management of blood lipids: diabetez systematic review and dose-response meta-analysis riabetes L-carnitine and diabetes management controlled trials. International Patients. Note: The Scientific Writing Academy is a project sponsored by IRCCS - Istituto di Ricerche Farmacologiche Mario Negri Bergamo, Italy and endorsed by the International Society of Nephrology that aims to teach the tools necessary to succeed in publishing scientific papers in international journals to researchers and physicians from around the world. Uneda K, Kawai Y, Yamada T, Kinguchi S, Azushima K, Kanaoka T, et al.

L-carnitine and diabetes management -

Ameliorating hypertension and insulin resistance in subjects at increased cardiovascular risk: effects of acetyl- l -carnitine therapy. Hypertension 54 , — acetyl- l -carnitine increases insulin sensitivity in individuals with low [GDR].

Insulin resistance is a risk factor for renal and cardiovascular disease and for the onset of type 2 diabetes. Giuseppe Remuzzi and colleagues report that oral administration of acetyl- l -carnitine increases insulin sensitivity and glucose tolerance in individuals with a low glucose disposal rate GDR.

Evidence from the early s indicates that, in individuals with type 2 diabetes, intravenous infusion of l -carnitine increases whole-body glucose use.

This effect is mediated by increased glucose storage and oxidative glucose consumption, which might be associated with improved lipid metabolism resulting from carnitine activity.

Remuzzi and colleagues enrolled in their study 32 individuals at high risk of decreased insulin sensitivity. In these participants, moreover, blood glucose concentration at 60 and 90 min following a standard glucose oral load decreased significantly.

Furthermore, the researchers observed in all 32 participants 17 of whom had hypertension a significant decrease in systolic blood pressure.

By contrast, diastolic blood pressure decreased significantly only in patients in the high GDR group. The researchers say that these data might be the first evidence of an antihypertensive effect of acetyl- l -carnitine in humans.

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Citation: Zamani M, Pahlavani N, Nikbaf-Shandiz M, Rasaei N, Ghaffarian-Ensaf R, Asbaghi O, Shiraseb F and Rastgoo S The effects of L-carnitine supplementation on glycemic markers in adults: A systematic review and dose-response meta-analysis.

Received: 27 October ; Accepted: 21 December ; Published: 10 January Copyright © Zamani, Pahlavani, Nikbaf-Shandiz, Rasaei, Ghaffarian-Ensaf, Asbaghi, Shiraseb and Rastgoo. This is an open-access article distributed under the terms of the Creative Commons Attribution License CC BY. The use, distribution or reproduction in other forums is permitted, provided the original author s and the copyright owner s are credited and that the original publication in this journal is cited, in accordance with accepted academic practice.

No use, distribution or reproduction is permitted which does not comply with these terms. com ; Samira Rastgoo, samiraa.

rastgoo gmail. Export citation EndNote Reference Manager Simple TEXT file BibTex. Check for updates. Introduction Hyperglycemia has increased dramatically in the last two decades. Materials and methods In the current study, the preferred reporting items for systematic reviews and meta-analyses PRISMA declaration was used Search strategy As part of our systematic literature search, we searched PubMed, Scopus, Web of Science, and the Cochrane databases for randomized control trials RCTs on the effects of L-carnitine supplementation on glycemic markers published up to October Data extraction Separate re-checks were conducted on all eligible RCTs, and two independent investigators MZ and MN extracted the following information.

Quality assessment An assessment of the quality of the studies was conducted using the Cochrane Collaboration tool Statistical analysis Stata Certainty assessment Using the GRADE Grading of Recommendations Assessment, Development, and Evaluation method, which was previously discussed, the overall degree of evidence certainty across the studies was evaluated and summarized Results Study selection The flow chart of the study was presented in Figure 1 and we described the selection process and the references retrieved from the database in this figure.

Figure 1. Flow chart of study selection for inclusion trials in the systematic review. Table 1. Collected samples from the patients were evaluated by Pars Azmun kits lot: and Abbott autoanalyzer model Alcyon , made in France. LDL-C levels were calculated by Equation 1 Insulin resistance was defined as the HOMA-IR index more than 3.

The protocol of this study was approved by the ethics committee of Tabriz University of Medical Sciences and registered in Clinical Trial Registration System at www. ir under the number IRCTN1.

Obtained data are expressed as mean ± standard deviation, frequency and percentage. Quantitative variables were compared by Student t-test. The demographic variables measured in the case and control groups to determine the compliance rate of participation were presented in Table 1.

Anthropometric indices and body fat of all 60 cases were presented in Table 2. a Data are presented as Mean ± SD. b Abbreviation: BMI, body mass index. b Between groups analysis. e Abbreviations: BF, body fat; BMI, body mass index; HC, hip circumference; WC, waist circumference; WHR, waist-hip ratio.

The results of the experiments performed in the two groups before and after the intervention were presented in Table 3. As indicated in Table 2 , patients in both the case and control groups had no significant difference before the intervention regarding weight, BMI, waist circumference, hip circumference, waist-hip ratio, and body fat.

After the intervention reduction was seen in mentioned variables compared to their initial values in the both groups, but this reduction was statistically significant in the case group in weight, waist circumference, hip circumference, and body fat.

b P value between groups analysis. c Abbreviations: FBS, fasting blood sugar; HDL-C, high-density lipoprotein-cholesterol; HOMA-IR, homeostasis model assessment for insulin resistance; LDL-C, low-density lipoprotein-cholesterol; TG, triglyceride.

d P value within groups analysis. It has been recognized that obesity is a disorder of energy balance, occurring when energy consumption and daily energy intake are not adequate.

L-carnitine and its esters have been proposed as a treatment for many conditions such as heart failure, angina and weight loss due to their roles in reducing oxidative stress 25 and plasma inflammatory markers 26 that is consistent with our result.

In our study, we observed a weight loss in both case and control groups, but this reduction was statistically significant in case group that received L-carnitine supplement compared to controls. It has been reported that L-carnitine has a useful effect on several diabetic risk parameters, including plasma lipids and lipoprotein This conversion could decrease triglycerides synthesis, and increase mitochondrial b-oxidation of fatty acids.

Studies that support this opinion indicated that L-carnitine decreases serum cholesterol, triglycerides, and free fatty acids 28 , the current study also observed a significant decrease in LDL-C, cholesterol and triglycerides in patients who received L-carnitine supplementation compared to the control group.

Our results are consistent with those of Gonzalez-Ortiz et al. Reduction of serum hypertriglyceridemia in diabetic patients who consumed L-carnitine resulted in decrease of triglycerides synthesis in the liver or inhibition of triglyceride release from the liver.

Moreover, L-carnitine induced significant reduction in total serum cholesterol in skeletal muscles of obese patients These results are consistent with our results, we observed a significant reduction in both case and control groups, but the reduction was stronger and clinically valuable in the case group, which shows the role of L-carnitine supplementation in this regard.

Increased fat mobilization from adipose tissue and insulin resistance to the antilipolytic actions cause diminished muscular uptake of glucose and lead to hyperlipidemia. Disordered insulin action is related to an oversupply of lipids.

Lipids increased availability causes elevated lipid stored in insulin target tissues e. muscle, liver adipose or increased plasma triglyceride Gonzalez-Ortiz et al.

in their study concluded that L-carnitine oral administration did not modify insulin sensitivity or the lipid profile. They administrated L-carnitine for a period of 4 weeks However, in our study, oral administration of L-carnitine with low calorie diet for a period of 8 weeks modified lipid profile, and also reduced insulin resistance.

In the current study, the weight loss due to oral administration of L-carnitine is associated with hypoglycemia because of elevated insulin sensitivity, thus decreasing insulin resistance in obese patients is due to regulating the cell energy metabolism or reducing free fatty acids.

These results are in agreement with those of Gonzalez-Ortiz et al. In addition, enhanced secretion of insulin from the beta-cells of the pancreatic islets or among an extra pancreatic mechanism is probably mediating hypoglycemia induced by L-carnitine. Moreover, the inflammatory effect of cytokine release during diabetes is one of the causative agents for the insulin resistance; L-carnitine may reduce this effect of cytokines Based on the results of different studies, intestinal L-carnitine absorption is saturated within two grams, so the oral administration of L-carnitine more than 2 grams per meal, is not beneficial and not recommended.

It seems that L-carnitine supplementation before each meal has a good effect in its absorption Receiving 15 grams of L-carnitine orally per day has no side effects in healthy persons OSL, observed safe level.

The National Institutes of Health NIH has noted that L-carnitine supplementation is well tolerated by most individuals in the intervention up to six months. However, there is the possibility of side effects such as gastrointestinal disorders including nausea, vomiting, stomachache, mild diarrhea, and also in a small number of cases who received this supplement, changes in body odor as fishy smell or euphoric mode was reported 35 , Due to the effect of L-carnitine supplementation a dose of mg twice daily with low-calorie diet on reducing fasting blood glucose, triglycerides, cholesterol and LDL-C levels, and insulin resistance HOMA-IR , prescribing this supplement in obese diabetic patients is recommended.

Last but not least, there are some limitations to the study including lack of possibility to examine other indicators of oxidative stress and antioxidant system components such as oxidized LDL-C, MDA, enzymatic activity of SOD and GPx, lack of patient cooperation for long-term follow-up like 6 months, one year and financial constraints in the evaluation of various serum inflammatory markers such as IL and TNF-α.

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Maangement you for visiting nature. You are using a browser version Metabolism-boosting foods limited support for CSS. To obtain the L-carnitine and diabetes management experience, L-carnitine and diabetes management wnd you use a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Ruggenenti, P. et al. Ameliorating hypertension and insulin resistance in subjects at increased cardiovascular risk: effects of acetyl- l -carnitine therapy. A L-carnitine and diabetes management list of the participating manageemnt in the Acetyl- l L-carnitine and diabetes management Study Group L-arnitine available in the appendix. Anders A. SimaMenotti CalvaniMunish MehraAntonino Amatofor the Caffeine pills for increased motivation Study Manaagement Acetyl- l -Carnitine Manabement Pain, Nerve Regeneration, and Vibratory Perception in Patients With Chronic Diabetic Neuropathy : An analysis of two randomized placebo-controlled trials. Diabetes Care 1 January ; 28 1 : 89— Efficacy end points were sural nerve morphometry, nerve conduction velocities, vibration perception thresholds, clinical symptom scores, and a visual analogue scale for most bothersome symptom, most notably pain. The two studies were evaluated separately and combined. RESULTS —Data showed significant improvements in sural nerve fiber numbers and regenerating nerve fiber clusters.

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