The use of levo-carnitine in children with renal disease: a review and a call for future studies

Influence of incorporating L-carnitine or Moringa oleifera leaves extract into semen diluent on cryosurvival and in vitro fertilization competence of buck sperm

This study aimed at scrutinizing efficiency of incorporating L-carnitine or M. oleifera leaves extract into semen diluent on improving cryopreservation capacity and in vitro fertilization ability of buck spermatozoa. Ejaculates (n=48) were collected by an artificial vagina from six adult Damascus bucks twice weekly during the breeding season (September-October). Following initial evaluation, ejaculates of each collection session from the same bucks were pooled, diluted (1:10) with glycerolized (3 % glycerol, v/v) tris-citric acid egg yolk diluent and were split into three aliquots. The first aliquot served as control, whereas the second and third aliquots were supplemented with 4 μL/mL L-carnitine and 400 μL/mL moringa leaves extract (v/v), respectively. Thereafter, all specimens were processed for cryopreservation and were stored in liquid nitrogen (-196 °C) for 12 months before post-thaw sperm criteria were analyzed by a computer-assisted sperm analysis (CASA) system. Integrity of sperm DNA post thawing was visualized in all semen groups by fluorescence imaging, and in vitro fertilization ability of spermatozoa was also determined. Inclusion of L-carnitine or moringa leaves extract into the diluent improved (P<0.05) post-thaw sperm physical, morphofunctional and kinematic attributes, whilst maintaining (P<0.05) integrity of sperm DNA throughout the freezing and thawing cycle. Consequently, both supplemented groups yielded higher (P<0.05) in vitro fertilization rates compared to control. These results accentuate the protective roles of these antioxidants on buck sperm against consequences of cryopreservation-induced oxidative stress, hence ameliorating post-thaw sperm quality and fertilization competence. This is crucial for successful application of AI and IVF in goat selective breeding programs.

A metabolic map and artificial intelligence-aided identification of nasopharyngeal carcinoma via a single-cell Raman platform

BACKGROUND

Nasopharyngeal carcinoma (NPC) is a complex cancer influenced by various factors. This study explores the use of single-cell Raman spectroscopy as a potential diagnostic tool for investigating biomolecular changes associated with NPC carcinogenesis.

METHODS

Seven NPC cell lines, one immortalised nasopharyngeal epithelial cell line, six nasopharyngeal mucosa tissues and seven NPC tissue samples were analysed by performing confocal Raman spectroscopic measurements and imaging. The single-cell Raman spectral dataset was used to quantify relevant biomolecules and build machine learning classification models. Metabolomic profiles were investigated using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS).

RESULTS

By generating a metabolic map of seven NPC cell lines, we identified an interplay of altered metabolic processes involving nucleic acids, amino acids, lipids and sugars. The results from spatially resolved Raman maps and UPLC-MS/MS metabolomics were consistent, revealing an increase of unsaturated fatty acids in cancer cells, particularly in highly metastatic 5-8F and poorly differentiated CNE2 cells. The classification model achieved a nearly perfect classification when identifying NPC and non-NPC cells with an ROC-AUC of 0.99 and a value of 0.97 when identifying 13 tissue samples.

CONCLUSION

This study unveils a complex interplay of metabolic network and highlights the potential roles of unsaturated fatty acids in NPC progression and metastasis. This renders further research to provide deeper insights into NPC pathogenesis, identify new metabolic targets and improve the efficacy of targeted therapies in NPC. Artificial intelligence-aided analysis of single-cell Raman spectra has achieved high accuracies in the classification of both cancer cells and patient tissues, paving the way for a simple, less invasive and accurate diagnostic test.

Lipidomics Reveals Myocardial Lipid Composition in a Murine Model of Insulin Resistance Induced by a High-Fat Diet

Ectopic fat accumulation in non-adipose tissues is closely related to diabetes-related myocardial dysfunction. Nevertheless, the complete picture of the lipid metabolites involved in the metabolic-related myocardial alterations is not fully characterized. The aim of this study was to characterize the specific lipid profile in hearts in an animal model of obesity/insulin resistance induced by a high-fat diet (HFD). The cardiac lipidome profiles were assessed via liquid chromatography-mass spectrometry (LC-MS)/MS-MS and laser desorption/ionization-mass spectrometry (LDI-MS) tissue imaging in hearts from C57BL/6J mice fed with an HFD or standard-diet (STD) for 12 weeks. Targeted lipidome analysis identified a total of 63 lipids (i.e., 48 triacylglycerols (TG), 5 diacylglycerols (DG), 1 sphingomyelin (SM), 3 phosphatidylcholines (PC), 1 DihydroPC, and 5 carnitines) modified in hearts from HFD-fed mice compared to animals fed with STD. Whereas most of the TG were up-regulated in hearts from animals fed with an HFD, most of the carnitines were down-regulated, thereby suggesting a reduction in the mitochondrial β-oxidation. Roughly 30% of the identified metabolites were oxidated, pointing to an increase in lipid peroxidation. Cardiac lipidome was associated with a specific biochemical profile and a specific liver TG pattern. Overall, our study reveals a specific cardiac lipid fingerprint associated with metabolic alterations induced by HFD.

The Dark Side of Energy Drinks: A Comprehensive Review of Their Impact on the Human Body

In recent years, the consumption of energy drinks by young adults and athletes has risen significantly, but concerns have been raised about the potential health risks associated with excessive consumption. These concerns include cardiovascular problems, nervous system disorders, and the potential for addiction. This review aims to examine the reported effects of acute or chronic abuse of energy drinks on human health. The analysis shows a significant prevalence of adverse effects, particularly on the cardiovascular and neurovegetative systems. In particular, the analysis identified nine cases of cardiac arrest, three of which were fatal. The aetiology of these adverse effects is attributed to the inherent neurostimulant properties of these beverages, of which caffeine is the predominant component. A comparison of documented effects in humans with experimental studies in animal models showed an overlap in results. This review highlights the need for greater rigour in the assessment of sudden cardiac death, particularly in young people, as legal substances such as energy drinks may be involved. We propose stricter limits on the consumption of these beverages than for caffeine, based on the evidence found and the data in the literature. This review also calls for the establishment of regulations governing the consumption of these products in view of their potential impact on human health.

Evaluation of the relationship between serum carnitine levels and intradialytic complications in children with kidney failure

BACKGROUND

Carnitine plays a crucial role in the metabolism of fatty acids as well as energy production. Previous research has suggested a significant decrease in carnitine levels in patients with kidney failure and those undergoing hemodialysis. Therefore, we designed this study to assess the prevalence and characteristics of carnitine deficiency and its association with hemodialysis complications in the pediatric population.

METHODS

This research was a pilot study of 29 children undergoing hemodialysis. Before hemodialysis, a 5-mL blood sample was drawn from each patient through a peripheral vein to measure serum-free carnitine levels, complete blood count with differential, blood urea nitrogen (BUN), creatinine, and electrolytes. Each patient was observed for intradialytic complications, including muscle cramps and hypotension, during 12 sessions of hemodialysis.

RESULTS

We included 26 participants with a mean age of 14.23 years undergoing hemodialysis. Carnitine deficiency was revealed in 54.8% of our participants. Also, there was no significant correlation between carnitine deficiency and age, gender, and BUN levels (P = 0.698, P = 0.43, and P > 0.05, respectively). Intradialytic complications, including episodes of hypotension and muscle cramps, were more frequent in patients with carnitine deficiency (P = 0.02, P = 0.01, respectively). Other reasons for muscle cramps, such as fluid overload, nutritional status, dialysis regimen, and other important lab results (phosphorus, magnesium, etc.), were ruled out.

CONCLUSION

In conclusion, we found a higher prevalence of carnitine deficiency in pediatric hemodialysis patients. Carnitine deficiency was significantly associated with increased intradialytic symptoms, including muscle spasms and hypotension. Our results could support a potential role of carnitine supplementation in pediatric patients with kidney failure for controlling intradialytic complications, but this requires further investigation. A higher resolution version of the Graphical abstract is available as Supplementary information.

The role of carnitine in maintenance dialysis therapy

Carnitine metabolism and homeostasis is significantly altered in patients receiving maintenance dialysis. Current literature in the adult and pediatric dialysis populations suggest a high prevalence of carnitine deficiency, which may lead to erythropoietin-resistant anemia, cardiomyopathy, and muscle weakness. However, the results of pediatric dialysis studies are limited and have not provided the evidence necessary to support strong recommendations or guidelines pertaining to carnitine management. The characteristics and function of carnitine, the definition and consequences of deficiency, a brief overview of recent adult studies, and current studies on carnitine supplementation in pediatric hemodialysis (HD) and peritoneal dialysis (PD) populations are discussed in this review.

Congenital Hyperinsulinism

Hyperinsulinemic hypoglycemia (HH) is fairly common in neonates, particularly those born to diabetic mothers and those who are either large or small for gestational age. Immediate management of the disease focuses on achieving normoglycemia through frequent high-calorie feedings and/or intravenous glucose administration. Glucagon may be used for unstable infants in whom intravenous access cannot be obtained and enteral feedings cannot be administered. HH that persists despite these interventions should raise concern for congenital hyperinsulinism (CHI), prompting clinicians to perform a thorough evaluation. CHI consists of a group of genetic disorders in which inappropriate insulin secretion results in persistent hypoglycemia. Defects can occur in the various genes that regulate the pathway for insulin secretion in the pancreatic β-cells. Pharmacologic therapies are used for long-term management of the disease coupled with either curative or therapeutic surgical intervention. Because of the developing brain's high demand for glucose, these infants are at increased risk for hypoglycemic brain injury. This review will describe the pathogenesis of CHI, outlining the more common genetic mutations and associated syndromes. We will also discuss the clinical presentation, diagnosis, and management of CHI while providing insight into the overall prognosis.

Relation of plasma carnitine and aminotransferases to alcohol dose and time of dependence

BACKGROUND

Serum aspartate, alanine aminotransferases (AST, ALT), and plasma carnitine are all indirect biomarkers of alcohol abuse. Carnitine transfers long-chain fatty acids from cytoplasm to mitochondria for β-oxidation. The aim of the study was to determine the relationship between daily alcohol intake, time of alcohol dependence, plasma carnitine, and serum aminotransferases.

PATIENTS

We studied 26 men who were addicted for 2-30 years, consuming ethanol from 75 to 700 g/day (alcoholic group), as well as 17 healthy men (control group).

RESULTS

In alcoholics, compared to the controls, we found: a significant increase in serum: AST (p = 0.0014), ALT (p = 0.0071), AST/ALT ratio (p < 0.000); significantly lower plasma free carnitine (FC) (p = 0.0316) and total carnitine (TC) (p = 0.0349); and a significant negative correlation between FC (r = -0.6200; R² = 0.3844; p = 0.0007), TC (r = -0.4365; R² = 0.1905; p = 0.0258), and time of alcohol dependence, suggesting carnitine as an indirect marker of alcohol abuse. We did not find any significant correlation between FC, TC, and levels of alcohol or aminotransferase activity.

CONCLUSION

In the alcoholic group, there was an increase in serum activity of AST, ALT, and AST/ALT ratio that confirms liver injury. In addition, we found low plasma FC and TC, which may indicate damage to mitochondrial β-oxidation caused by alcohol metabolites. The significantly higher plasma FC and TC in patients consuming the most, compared to patients consuming smaller doses of alcohol, may be caused by a lower carnitine demand of injured liver cells, decreased urinary carnitine excretion by impaired renal tubules, and leakage of carnitine into the blood from damaged muscles by the higher quantities of alcohol. The negative correlation between carnitine concentration and time of alcohol dependence may suggest the potential use of carnitine for treatment of alcohol abuse.

Protective Effects of L-Carnitine Against Delayed Graft Function in Kidney Transplant Recipients: A Pilot, Randomized, Double-Blinded, Placebo-Controlled Clinical Trial

OBJECTIVE

Delayed graft function (DGF) is an early complication after deceased donor kidney transplantation with significant adverse effects on graft outcomes. Ischemia-reperfusion injury during transplantation is a major cause of DGF. Tissue concentrations of carnitine, an antioxidant and regulator of cellular energy supply, decrease in the kidney following ischemia-reperfusion insult. Based on promising animal data, this study evaluated the possible protective effect of L-carnitine against DGF.

DESIGN

This study is a pilot, randomized, double-blind, placebo-controlled clinical trial that was conducted on kidney transplantation patients in kidney transplant ward of Imam Khomeini hospital complex affiliated to Tehran University of Medical Sciences, Tehran, Iran.

SUBJECTS

Patients older than 14 years old undergoing their first kidney transplantation from a deceased donor were evaluated for eligibility to take part in this study. Fifty-six patients were randomly assigned to L-carnitine or placebo groups.

INTERVENTION

During this trial, 3 g of oral L-carnitine or placebo was administered in 3 divided doses each day for 4 consecutive days starting the day before kidney transplantation (i.e., days -1, 0, 1, and 2).

MAIN OUTCOME MEASURE

The need for dialysis within the first week after transplantation, serum creatinine and urine output were assessed daily. After hospital discharge, patients were followed for 3 months regarding organ function.

RESULTS

DGF incidence did not differ between the L-carnitine and placebo groups (18.51% vs. 23.8%, respectively; P = .68). Total allograft failure within 3 months after kidney transplantation happened in 6 patients in the placebo and 1 patient in the L-carnitine group (P = .05).

CONCLUSION

This study showed no protective effects of oral L-carnitine supplementation against DGF occurrence recipients; however, 3-month graft loss was lower in the L-carnitine supplemented group.

L-carnitine supplementation in patients with HIV/AIDS and fatigue: a double-blind, placebo-controlled pilot study

Background

The purpose of this study was to determine the effect of L-carnitine supplementation on fatigue in patients with terminal human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS).

Methods

In this randomized, double-blind, placebo-controlled, parallel-group study, patients who had end-stage HIV/AIDS with carnitine deficiency and fatigue received 3 g of oral L-carnitine or placebo for 2 weeks, followed by a 2-week, open-label phase with the same amount of L-carnitine for all patients. The primary outcome was the degree of fatigue according to the Brief Fatigue Inventory. Secondary outcomes included serum carnitine and lactate levels, physical, emotional, social, and functional well-being, performance status, mood, and CD4 count.

Results

Eighteen patients in the treatment arm and 17 in the placebo arm completed the trial. At the end of the double-blind phase, total and free carnitine levels in the treatment arm rose from 28±9 to 48±17 nM/L (P<0.001) and from 24±8 to 40±13 nM/L (P<0.001) respectively, with no changes in the placebo arm. The primary outcome, ie, fatigue measured at the end of the blinded phase, did not improve. Secondary outcomes of function, quality of life, and mood did not show improvement either. The secondary outcome of serum lactate decreased from baseline in the treatment group (1.45±0.76 to 1.28±0.52 mmol/L) and increased in the placebo group (1.38±0.62 to 1.84±0.74 mmol/L; P<0.005).

Conclusion

Our study suggests that 3 g of oral L-carnitine supplementation for 2 weeks in terminally ill HIV/AIDS patients does not improve fatigue. This study might help to determine the dose and duration of treatment used in future clinical trials, as higher doses and/or longer periods of supplementation might be needed in order to detect an improvement. The reduction in serum lactate levels suggests a potential role for L-carnitine supplementation in patients undergoing certain types of antiretroviral therapy. This study contributes evidence-based data to the field of alternative and complementary medicine, a multibillion dollar industry in which controlled studies are not the norm.

Nonesterified fatty acids and cardiovascular mortality in elderly men with CKD

BACKGROUND AND OBJECTIVES

Although nonesterified fatty acids (NEFAs) are essential as energy substrate for the myocardium, an excess of circulating NEFAs can be harmful. This study aimed to assess plausible relationships between serum NEFA and mortality due to cardiovascular disease (CVD) in individuals with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a prospective cohort study from the third examination cycle of the Uppsala Longitudinal Study of Adult Men, a population-based survey of 1221 elderly men aged 70-71 years residing in Uppsala, Sweden. Data collection took place during 1991-1995. All participants had measures of kidney function; this study investigated 623 (51.7%) of these patients with manifest CKD (defined as either eGFR<60 ml/min per 1.73 m(2) or urine albumin excretion rate ≥20 µg/min). Follow-up for mortality was done from examination date until death or December 31, 2007. After a median follow-up of 14 years (interquartile range, 8-16.8), associations of NEFAs with mortality (related to all causes, CVD, ischemic heart disease [IHD], or acute myocardial infarction) were ascertained.

RESULTS

The median serum NEFA was 14.1 mg/dl (interquartile range, 11.3-17.8). No association was found with measures of kidney function. Diabetes and serum triglycerides were the only multivariate correlates of NEFA. During follow-up, 453 participants died, of which 209 deaths were due to CVD, including 88 IHD deaths, with 41 attributed to acute myocardial infarction (AMI). In fully adjusted covariates, serum NEFA was an independent risk factor for all-cause mortality (hazard ratio [HR] per log2 increase, 1.22; 95% confidence interval [95% CI], 1.00 to 1.48) and CVD-related death (HR, 1.51; 95% CI, 1.15 to 1.99), including both IHD (HR, 1.51; 95% CI, 1.00 to 2.32) and AMI mortality (HR, 2.08; 95% CI, 1.09 to 3.98).

CONCLUSIONS

Elevated serum NEFA associated with CVD mortality, and particularly with mortality due to AMI, in a homogeneous population of older men with moderate CKD.

Serum carnitine level and its associated factors in patients with chronic viral hepatitis

ABSTRACT: 

Aim: Serum carnitine level and its associated factors have been evaluated in patients with chronic viral hepatitis. Methods: Patients with confirmed chronic viral hepatitis based on the serological markers and liver biopsy were included. In total, 86 volunteers and 86 patients with chronic viral hepatitis completed the study. Demographic data, type of treatment regimen and nutritional status of the patients were recorded and one blood sample was collected from each patient after an overnight fasting. A double antibody sandwich ELISA kit was used to measure carnitine serum level. Results: Mean ± standard deviation of serum carnitine level in the case and control groups were 34.3 ± 15.3 and 55.7 ± 28.4 μmol/l, respectively (p = 0.001). Regarding carnitine deficiency definition, 64 out of 86 patients (74.4%) and 21 out of 86 (24.5%) healthy individuals suffered from carnitine deficiency (p < 0.001). Carnitine dietary intake was significantly lower (p < 0.001). Compared with patients with chronic hepatitis C infection, a more severe form of carnitine deficiency was detected in patients with chronic hepatitis B infection (18.39 ± 15.68 μmol/l vs 42.30 ± 32.92 μmol/l; p = 0.03). In addition, serum carnitine level (41.1 ± 14.8 μmol/l) was significantly higher in the cirrhotic than noncirrhotic patients (31.60 ± 13.2 μmol/l; p = 0.04). Conclusion: Although the cirrhotic patients had higher serum carnitine level compared with noncirrhotic patients, serum carnitine level in the patients with chronic hepatitis was significantly lower than the healthy individuals. Also compared with the defined cut-off point for normal carnitine serum level, carnitine deficiency was common in Iranian patients with chronic hepatitis.

Evaluation of serum level of carnitine in HIV-positive individuals and its possible explanatory factors

Aims: This cross-sectional study evaluated the status of serum carnitine level and its possible explanatory factors in Iranian HIV-positive patients. Materials & methods: During a 1-year period, 210 HIV-positive patients older than 18 years of age were enrolled in the study. Serum carnitine concentrations of the patients were measured using radioimmunoassay kits. Probable correlations between the patients’ demographic and clinical characteristics with their serum levels of carnitine were determined in this study. Results: In comparison with normal serum concentration of carnitine in a healthy population, 63.45% of the patients had carnitine deficiency. Receiving antiretroviral regimen, duration of HIV infection, receiving fibrate drugs, serum total cholesterol, fasting blood sugar and serum triglyceride had significant correlations with serum level of carnitine of the patients. Conclusion: The results of the present study showed that carnitine deficiency is prevalent in Iranian HIV/AIDS patients. Nutritional risk assessment of HIV-positive individuals at first visit and in the follow-up is essential.

Effect of carnitine supplementation on lipid profile and anemia in children on chronic dialysis

We prospectively evaluated the effects of L-carnitine supplementation on plasma free carnitine (FC) levels, serum lipid profile, and erythropoietin (rhEPO) requirement in 24 children treated with peritoneal dialysis (PD; n=16) or hemodialysis (HD; n=8). The study was divided into a 3-month observation period, and a 3-month treatment period during which patients received 20 mg/kg per day of L-carnitine given orally. Clinical, biochemical, and hematological data were collected every 3 months. FC levels were measured in plasma and peritoneal dialysate by tandem mass spectrometry. There were no statistically significant changes in lipid levels, hemoglobin, or rhEPO requirements during the course of the study. Fifteen patients (13 PD, 2 HD) had plasma FC levels measured before and after treatment; FC levels increased from 32.1 +/- 14.1 micromol/l to 80.9 +/- 38.7 micromol/l (P<0.001). In PD patients, dialysate FC losses increased from 106 +/- 78 micromol/day at baseline to 178 +/- 119 micromol/day after supplementation. Positive correlations between FC plasma levels and dialysate levels (R=0.507) or daily excretion (R=0.603) were found after treatment. In our case series, an oral dose of 20 mg/kg per day of L-carnitine restored FC levels and produced a positive carnitine balance with no significant effects on hematological parameters or lipid profile over a 3-month period. Prolonged treatment duration may be required to obtain significant results.