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Systemic primary carnitine deficiency (PCD) is an autosomal recessive disorder caused by mutations in the SLC22A5 gene that encodes carnitine transporter, OCTN2. Transporter deficiency leads to defective fatty acid oxidation. Signs and symptoms ranging from liver injury in children to cardiomyopathy and skeletal myopathy in adults, manifest during periods of stress and fasting. Though acute liver failure is infrequently described, young children presenting as acute liver failure should be screened for fatty acid oxidation defects including PCD by testing plasma for amino acids and further confirmed by genetic sequencing. Early identification and treatment using L-carnitine is lifesaving. Our patient presented as acute liver failure and diagnosis of PCD was confirmed by metabolic screening and genetic sequencing. He responded to the treatment.

Many studies have investigated the effects of soy isoflavones on weight control, but few have focused on the role of equol, a gut-derived metabolite of daidzein with greater bioavailability than other soy isoflavones.This study examined the association of equol production with obesity and explored the mediating roles of equol-related gut microbiota and microbial carnitine metabolites.This 6.6-y prospective study included 2958 Chinese adults (2011 females and 947 males) aged 60.6 ± 6.0 y (mean ± SD) at baseline. Urinary equol and isoflavones were measured using HPLC-tandem MS. BMI, percentage fat mass (%FM), and serum triglycerides (TGs) were assessed every 3 y. Metagenomics sequencing and assessment of carnitine metabolites in feces were performed in a subsample of 897 participants.Urinary equol, but not daidzein and genistein, was independently and inversely associated with the obesity-related indicators of BMI, %FM, and a biomarker (TGs). Equol producers (EPs) had lower odds of adiposity conditions and a reduced risk of 6.6-y obesity progression than non-EPs among total participants. Gut microbial analyses indicated that EPs had higher microbiome species richness (P = 3.42 × 10-5) and significantly different β-diversity of gut microbiota compared with the non-EP group (P = 0.001), with 20 of 162 species differing significantly. EPs (compared with non-EPs) had higher abundances of Alistipes senegalensis and Coprococcus catus but lower abundances of Ruminococcus gnavus (false discovery rate 0.05). Among the 7 determined fecal acylcarnitine metabolites, palmitoylcarnitine, oleylcarnitine 18:1, and stearylcarnitine were inversely associated with EPs but positively correlated with obesity conditions and progression. Path analyses indicated that the beneficial association between equol and obesity might be mediated by gut microbiota and decreased production of 3 acylcarnitines in feces.This study suggests a beneficial association between equol and obesity, mediated by the gut microbiome and acylcarnitines, in adults.This trial was registered at clinicaltrials.gov as NCT03179657.

Medium-chain acyl-coenzyme A dehydrogenase deficiency (MCADD) is a rare inherited metabolic disorder of fatty acid β-oxidation and one of the most common inborn errors of metabolism. The incidence of MCADD varies among regions and ethnic groups. To date, few cases of MCADD have been documented in China.The present study aimed to find out the novel genetic pathogenic variants in the Chinese patients and evaluate the detection rate of the disease of high-frequency ACADM pathogenic variants in different regions of China.6 cases of MCADD were screened by tandem mass spectrometric (MS/MS) among 245 054 newborns. We performed next-generation sequencing on 6 families of infants with MCADD. We used the REVEL method to predict the protein function of the detected missense variants and used SPDBV 4.10 to predict the protein 3D structure model. We identified pathogenic variants of ACADM gene in 6 cases of MCADD, and then assessed these variants through Sanger sequencing and association analysis.The incidence of neonatal MCADD was 1/40,842 in Henan province. Among the 6 patients, five cases were compound heterozygous variants, one case was homozygous variants. DNA sequencing revealed 4 known (c.449_452del, c.1085G A, c.1229 T C, c.589A G) and 3 novel mutations (c.849 + 5_849 + 8del, c.427A G, c.1181C T) in the ACADM gene. Mutation c.1085G A (p.G362E) was most frequent among Henan people and shows obvious differences between North and South of China.MCADD is relatively rare in China, and c.1085G A (p.G362E) is a common mutation in Henan population. Our findings, especially novel variants, will help improve the understanding of the genetic background and have facilitated clinical diagnosis and genetic counseling for the affected families.

Mitochondrial carnitine/acylcarnitine carrier (CAC) is a member of the mitochondrial carrier (MC) family and imports acylcarnitine into the mitochondrial matrix in exchange for carnitine, playing a pivotal role in carnitine shuttle, crucial for fatty acid oxidation. The crystallized structure of CAC has not been solved yet, however, the availability of several in vitro/in silico studies, also based on the crystallized structures of the ADP/ATP carrier in the cytosolic-conformation and in the matrix-conformation, has made possible to confirm the hypothesis of the single-binding centered-gated pore mechanism for all the members of the MC family. In addition, our recent bioinformatics analyses allowed quantifying in silico the importance of protein residues of MC substrate binding region, of those involved in the formation of the matrix and cytosolic gates, and of those belonging to the Pro/Gly (PG) levels, proposed to be crucial for the tilting/kinking/bending of the six MC transmembrane helices, funneling the substrate translocation pathway. Here we present a combined in silico/in vitro analysis employed for investigating the role played by a group of 6 proline residues and 6 glycine residues, highly conserved in CAC, belonging to MC PG-levels. Residues of the PG-levels surround the similarly located MC common substrate binding region, and were proposed to lead conformational changes and substrate translocation, following substrate binding. For our analysis, we employed 3D molecular modeling approaches, alanine scanning site-directed mutagenesis and in vitro transport assays. Our analysis reveals that P130 (H3), G268 (H6) and G220 (H5), mutated in alanine, affect severely CAC transport activity (mutant catalytic efficiency lower than 5 % compared to the wild type CAC), most likely due to their major role in triggering CAC conformational changes, following carnitine binding. Notably, P30A (H1) and G121A (H3) CAC mutants, increase the carnitine uptake up to 217 % and 112 %, respectively, compared to the wild type CAC.

Previously, we reported, based on an untargeted metabolomics, carnitine derivatives are part of a mechanism to overcome impaired mitochondrial functioning triggered by an acyl-group overflow in CHO cells. In this study, we analyzed the cell-specific rates of 24 selected metabolites using two metrics: correlation coefficients and root-mean-square deviations (RMSDs) between glucose-fed versus glucose/lactic acid-fed cultures. The time-course profiles of acetylcarnitine, adipoylcarnitine, glutarylcarnitine, glutamate, and succinate exhibited significant negative correlations between the two culture conditions. Based on RMSDs, seven carnitine derivatives, 3-hydroxy-methyl-glutarate, mevalonate, pyridoxamine-5-phosphate, succinate, and glycine were substantially different. The analyses from the two metrics reveal a distinctive rearrangement of rates from the following metabolic pathways: (i) high secretion rates of carnitines as part of the acyl-group removal, (ii) low secretion rates of succinate, related to the tricarboxylic acid cycle and the electron-transport chain, (iii) low secretion rates of pyridoxamine-5-phosphate - a co-factor for amino acid catabolism, transaminations, and transsulfuration, and (iv) increases in the consumption rates of glutamate and glycine, both used to produce glutathione. The rewiring in rates observed upon feeding lactic acid is best explained by the activation of pathways supporting homeostasis of acyl-groups and antioxidant synthesis, which are required for continuous proper functioning of oxidative phosphorylation.

l-Carnitine was suggested to prevent the progression of atherosclerosis, myocardial and neurologic injury, and exhibited cardioprotective effects. However, epidemiological data on circulating l-carnitine and risks of cardiovascular events in the setting of stroke is rare. We aimed to explore the relationships between plasma l-carnitine and cardiovascular events and stroke recurrence after ischemic stroke in a nested case-control study.A total of 323 cardiovascular events (including 264 recurrent strokes) and 323 matched controls (free of recurrent cardiovascular events) were included. Study outcomes included cardiovascular events and recurrent stroke after ischemic stroke. Plasma l-carnitine concentrations were measured by ultra-high-performance LC-MS/MS. Conditional logistic regression models were used to estimate odds ratios (ORs) of stroke outcomes. Plasma l-carnitine was inversely associated with cardiovascular events (OR = 0.69, 95% CI: 0.57-0.84 per SD) and recurrent stroke (OR = 0.72, 95% CI: 0.58-0.88 per SD) after adjusting for established risk confounders. Compared with the lowest tertile of l-carnitine, adjusted ORs of cardiovascular events and recurrent stroke for participants in the highest tertiles were 0.35 (95% CI: 0.21-0.57) and 0.36 (95% CI: 0.21-0.62), respectively. In addition, l-carnitine provided incremental predictive ability beyond established risk factors, shown by increase in C statistics, net reclassification improvement and integrated discrimination improvement.Higher l-carnitine levels were associated with lower risks of cardiovascular events and recurrent stroke after ischemic stroke. Our findings provided evidence supporting plasma l-carnitine as a potential prognostic marker in risk discrimination and stratification in patients with ischemic stroke.Clinicaltrials.gov as NCT01840072. URL: https://www.gov.

Valproic acid (VPA) is a common antiepileptic drug that is also used routinely for various psychiatric disorders. VPA toxicity typically manifests as central nervous system depression, while hyperammonemic encephalopathy and hepatotoxicity are potentially life-threatening complications.We describe the case of a 56-year-old man who presented to the emergency department after an intentional VPA overdose, was found to have hyperammonemia, and was treated with L-carnitine exclusively. He was subsequently admitted to the hospital for monitoring and serial laboratory testing. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although VPA toxicity has conventionally been managed by gastric decontamination, L-carnitine, and, in severe and refractory cases, extracorporeal removal, recent literature supports the use of carbapenem antibiotics, particularly meropenem. Thus, we report the details of current treatment modalities for VPA toxicity by reviewing current literature.

Episodic weakness is typically associated with a group of disorders so called periodic paralyses. Their major causes are mutation of ion channels, and have rarely been linked to mitochondrial disorders. We report a 20-year-old man with episodic weakness and axonal sensorimotor neuropathy since the age of 10 years. Analysis of the next generation sequencing data of the entire mitochondrial genome extracted from the blood revealed a homoplasmic m.9185T C variant in MT-ATP6. Acetazolamide may be responsive for episodic weakness, and supplements with l-carnitine with coenzyme-Q10 seem to be beneficial as well. To the best of our knowledge, this is the first report in Taiwan which reveals episodic weakness and sensorimotor polyneuropathy as a unique phenotype of MT-ATP6 mutations.

Objectives To evaluate the effect of L-carnitine (LC) in combination with leucine supplementation on muscle strength and muscle hypertrophy in aged women participating in a resistance exercise training (RET) program. Design/Setting/Participants Thirty-seven out of sixty (38.3% dropout) healthy women aged 60–75 years (mean 67.6 ± 0.7 years) completed the intervention in one of three groups. One of the supplemented groups received 1 g of L-carnitine-L-tartrate in combination with 3 g of L-leucine per day (LC+L group; n = 12), and the second supplemented group received 4 g of L-leucine per day (L group; n = 13). The control group (CON group; n = 12) received no supplementation. Intervention All three groups completed the same RET protocol involving exercise sessions twice per week for 24 weeks. Measurements Before and after the experiment, participants performed isometric and isokinetic muscle strength testing on the Biodex dynamometer. The cross-sectional areas of the major knee extensors and total thigh muscles were assessed using magnetic resonance imaging. Fasting serum levels of insulin-like growth factor-1 (IGF-1), myostatin and decorin, and plasma levels of total carnitine (TC) and trimethylamine-N-oxide (TMAO) levels were measured. Results The 24-week RET significantly increased muscle strength and muscle volume, but the group and time interactions were not significant for the muscle variables analyzed. Plasma total carnitine increased only in the LC+L group (p = 0.009). LC supplementation also caused a significant increase in plasma TMAO, which was higher after the intervention in the LC+L group than in the L (p < 0.001), and CON (p = 0.005) groups. The intervention did not change plasma TMAO concentration in the L (p = 0.959) and CON (p = 0.866) groups. After the intervention serum decorin level was higher than before in both supplemented groups combined (p = 0.012), still not significantly different to post intervention CON (p = 0.231). No changes in serum IGF-1 and myostatin concentrations and no links between the changes in blood markers and muscle function or muscle volume were observed. Conclusions LC combined with leucine or leucine alone does not appear to improve the effectiveness of RET.

To assess efficacy of dietary patterns modification with the use of specialized food in patients with non-alcoholic steatohepatitis (NASH).We developed new specialized food (SPP2) based on literature data on the role of dietary patterns in pathogenesis of NASH. It contained -3 PUFAs, soluble dietary fiber, phospholipids, -lipoic acid, coenzyme Q10, L-carnitine, complex of vitamins. Patients with NASH (per EASL guidelines), were invited to participate in the study and were randomly assigned to receive either isocaloric diet (ICD) alone (based on the results of indirect calorimetry Cosmed, Italy) or isocaloric diet with specialized food (2 portions of SPP2 a day), for 14 days. Repeated examinations of body composition with phase angle analysis (InBody, Republic of Korea) and blood chemistry were performed at baseline (BL) and after 14 days (EOT). The patients were advised to follow usual physical activity during the study. Non-parametric statistics was used to compare BL and EOT characteristics in the groups.The groups did not differ by age, proportion of females, and baseline characteristics of body composition. Adherence to the diet was 87.5% in the ICD group and 88.2% in the ICD+SPP group (p=0.65). Compliance with the use of SPP was 100%. In the ICD+SPP group significant reduction of body weight was achieved (117.530.1 kg initially, vs 114.928.8 kg at EOT; p=0.007), whereas in the ICD group it was not statistically significant (106.722.1 kg at BL vs 104.016.8 kg at EOT, respectively; p=0.07). In contrast to the ICD group, in those who received ICD+SPP significant decrease in cholesterol (5.31.3 mmol/L at BL vs 4.61.3 mmol/L at EOT; p=0.003), LDL (3.71.0 mmol/L vs 3.31.0 mmol/L, respectively; p=0.009), alkaline phosphatase (132.699.1 vs 112.087.0 U/L; p=0.04), GGT (54.533.2 vs 37.519.7 U/L; p=0.04), insulin resistance index (6.13.2 vs 3.21.5, respectively; p=0.04) was detected.Modification of dietary patterns with the use of a specialized food in combination with low-calorie diet allows achieving significant reduction of weight and improve lipid and carbohydrate metabolism, reduce severity of cholestasis in patients with NASH.Цель. Оценить эффективность модификации паттернов питания при помощи специализированного продукта (СПП), специально разработанного в ходе настоящей работы на основе анализа структуры питания больных неалкогольным стеатогепатитом (НАСГ). Материалы и методы. Разработан новый СПП (СПП2) для лечения больных НАСГ с включением в состав -3-полиненасыщенных жирных кислот, растворимых пищевых волокон, фосфолипидов, -липоевой кислоты, коэнзима Q10, L-карнитина, комплекса витаминов. В исследование включены 25 больных НАСГ, рандомизированных в следующие группы: тех, кто получал только изокалорийную диету ИКД [на основе определения энерготрат покоя методом непрямой калориметрии (Quarck RMR, Италия)] группа ИКД (n=8); или ИКД в сочетании с СПП (2 порции СПП2 в день, 14 дней; группа ИКД+СПП, n=17). Эффективность лечения оценивалась на основании биохимических параметров крови и оценки состава тела биоимпедансным методом до лечения и на 15-й день исследования. Результаты. Группы пациентов не отличались по возрасту, половому составу, а также исходным параметрам состава тела. Приверженность рациону составила 87,5% в группе ИКД и 88,2% в группе ИКД+СПП (р=0,65). Комплаентность приему СПП составила 100%. В группе ИКД+СПП достигнуто значимое снижение массы тела (117,530,1 кг исходно в сравнении с 114,928,8 кг в конце исследования; p=0,007), в то время как в группе ИКД редукция массы тела не достигла статистически значимых отличий (106,722,1 кг в сравнении с 104,016,8 кг соответственно; р=0,07). В отличие от группы ИКД в группе ИКД+СПП выявлено значимое снижение уровней холестерина (5,31,3 ммоль/л исходно, 4,61,3 ммоль/л в конце исследования; р=0,003), липопротеидов низкой плотности (3,71,0 ммоль/л в сравнении с 3,31,0 ммоль/л; р=0,009), щелочной фосфатазы (132,699,1 в сравнении с 112,087,0 Е/л; р=0,04), -глутамилтрансферазы (54,533,2 в сравнении с 37,519,7 Е/л; р=0,04), индекса инсулинорезистентности (6,13,2 в сравнении с 3,21,5 соответственно; р=0,04). Заключение. Модификация паттернов питания с включением в состав изокалорийного рациона специализированного пищевого продукта позволяет достичь значимой редукции массы тела и улучшения показателей липидного и углеводного обмена, уменьшения выраженности синдрома холестаза у больных НАСГ.

Trimethylamine N-oxide (TMAO) is a gut-derived atherogenic metabolite. However, the role of TMAO and its precursors in the development of stroke remains unclear. We aimed to examine the associations between metabolites in TMAO biosynthesis and stroke risk.A nested case-control study was performed in a community-based cohort (2013-2018, n = 16,113). We included 412 identified stroke cases and 412 controls matched by age and sex. Plasma carnitine, choline, betaine, trimethyl lysine (TML), and TMAO were measured by ultrahigh performance liquid chromatography-tandem mass spectrometry. Conditional logistic regression analyses were used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs) between these biomarkers and stroke risk.After adjustment for body mass index, smoking, hypertension, educational attainment, and estimated glomerular filtration rate, the corresponding OR for the highest versus lowest quartile was 1.74 (95% CI: 1.16-2.61, P trend = 0.006) for total stroke and 1.81 (95% CI: 1.14-2.86, P trend = 0.020) for ischemic stroke in an essentially linear dose-response fashion. A significant association between TMAO and nonischemic stroke was shown as a J-shape with OR for the highest versus second quartile of 5.75 (95% CI: 1.73-19.1). No meaningful significant risk association was found among plasma carnitine, choline, betaine, and TML with stroke risk.Increased TMAO was associated with higher stroke risk in the community-based population, whereas the TMAO precursors carnitine, choline, betaine, and TML were not associated. Further studies are warranted to confirm these findings and to further elucidate the role of TMAO in the development of stroke.

l-carnitine is a well-known an antioxidant that enhanced lipid metabolism. Therefore, this study investigated the influence of supplementing l-carnitine (LC) to in vitro culture medium on preimplantation development, quality, cryotolerance and transcription profile of candidate genes. Following in vitro fertilization, embryos at zygote stage were cultured with medium supplemented with LC at 1.5 mM and fetal calf serum (FCS) at 0, 2.5, 5, 7.5 and 10% of the CR1-aa culture media. Intracellular quality of produced embryos was measured using different fluorescent stains that measured reactive oxygen species (ROS), lipid and mitochondria intensities. In addition, total cell number and total apoptotic cells were counted per embryo. Quantitative expression of candidate genes was conducted to find out molecular response of embryos after treatment. Moreover, vitrification was done at day 8 of preimplantation development to evaluate post-thaw embryo viability. The results indicated improved blastocyst formation rate at day 8 of preimplantation development (day zero = day of IVF) when embryos cultured with LC supplementation at low FCS at levels of 2.5% (35.3%) and 5% (34.7%) compared to control (25.9%), LC + FCS 7.5% (26.5%) and LC + FCS 10% (28.1%) groups. The total number of blastocyst cells that were cultured with LC + FCS 2.5% and LC + FCS 5% was increased and the number of dead cells (apoptotic) was decreased compared to control counterparts. Intracellular mitochondria activity was enhanced and resulted in reduction of cytoplasmic lipid in embryos treated with LC + FCS 2.5% and LC + FCS 5% compared with other experimental embryo groups. In addition, intracellular reactive oxygen species level was reduced in LC + FCS 2.5%, LC + FCS 5% and LC + FCS 7.5% compared to control and LC + FCS 10% groups. The expression profile of genes regulating embryo quality (BCL2), metabolic activity (GLUT1, CPT2 and TFAM), lipolysis (LIPE, AMPKa1 and ACCα), resistance to stress (SOD2) and ability to induce pregnancy (IFNt) was up-regulated under low FCS (2.5% and 5%) combined with LC supplementation. On the other hand, genes regulating lipogenesis were down-regulated (ACSL3 and S1PR). It can be concluded that LC is an efficient culture media supplement when added with FCS at 2.5 and 5% which improved blastocyst development rate and quality. These improvements are due to enhanced utilization of intracellular embryo lipid that subsequently increased cryotolerance through orchestrating genes involved in various activities of bovine embryos.

Busulfan (Bus), is an alkylating agent widely used in chemotherapy which has been proven to possess toxic side effects on testicles. This study was carried out to compare the probable treatment effects of resveratrol (Res) or/and l-carnitine (Lca), as strong antioxidants, on the testicular tissue as well as on the level of sex hormones in busulfan-induced azoospermic rat models. A total of 78 adult male rats, were divided into six different experimental groups including: 1) Control; 2) Lca + Res; 3) BUS; 4) Bus + Lca; 5) BUS + Res and 6) Bus + Lca + Res. Busulfan was intraperitoneally administered in a single dose (10 mg/kg b.w), while resveratrol (20 mg/kg b.w/day) and l-carnitine (200 mg/kg b.w/day) were orally administered by gavage during 48 consecutive days to the rats. At the end of the experiment in all groups the level of LH, FSH, and testosterone were biochemically analyzed by ELISA and the testicular tissue evaluated histologically using stereological technique. Results showed that Lca or/and Res, increased the body and testis weight, the volume of the testis, interstitial tissue, germinal epithelium, and seminiferous tubule, the number of the different cells of germinal epithelium and the level of testosterone. On the other hand, Lca, Res and their combination decreased the concentration of LH and FSH compared to the group treated with Bus. In conclusion, these results suggested that l-carnitine or/and resveratrol treatment significantly attenuated busulfan -induced changes of the rat reproductive system led to the recovery of both testis and sperm parameters. However, co-administration of L-ca and Res was more effective than their individual treatment. This combination may alleviate the side effects of alkylating drugs, such as busulfan and may be beneficial for spermatogenesis.

Chiral drugs are of great significance in drug development and life science because one pair of enantiomers has a different combination mode with target biological active sites, leading to a vast difference in physical activity. Metal-organic framework (MOF)-based chiral hybrid materials with specific chiral sites have excellent applications in the highly effective sensing of drug enantiomers. Sitagliptin and clonidine are effective curing drugs for controlling diabetes and hypertension, while insulin and norepinephrine are the biomarkers of these two diseases. Excessive use of sitagliptin and clonidine can cause side effects such as stomach pain, nausea, and headaches. Herein, through post-synthetic strategy, MOF-based chiral hybrid material

Objectives Medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is an autosomal recessive disorder of the fatty acid oxidative metabolism. This study aimed to investigate the epidemiological characteristics, the spectrum of variation, clinical phenotype, and prognosis of MCADD in Chinese newborns. Methods We retrospectively analysed newborn screening (NBS) data in the Zibo area from January 2016 to March 2022 and summarized 42 cases recently reported in Chinese neonates. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and next-generation sequencing (NGS) were used to detect the concentrations of carnitine in the blood spots and for diagnosis. Results A total of 183,082 newborns were detected, and six patients were diagnosed with MCADD (1/3,0514). The primary octanoylcarnitine (C8) and the octanoylcarnitine/decanoylcarnitine ratio (C8/C10) were elevated in all patients. Gene analysis revealed four known and four novel variants of the ACADM gene. Five patients were asymptomatic and developed normally under dietary guidance. One child died of vaccination-induced MCADD, presenting with hypoglycemia and elevated acylcarnitines. Conclusions The incidence of MCADD in Chinese newborns varies geographically from 1/222,903 to 1/30,514, and the most common pathogenic variant is c.449_452 del CTGA (p. T150Rfs∗4) in ACADM gene with a frequency of 27.7%. HPLC-MS/MS and genetic analysis are beneficial for early prevention and good prognosis of MCADD.

Carnitine biosynthesis has been related to fatty acid oxidation, a process probably exerting neuroprotective effects. However, the role of carnitine biosynthesis in the development of ischemic stroke (IS) remains unclear. We aimed to examine the associations between plasma markers of carnitine biosynthesis and the IS risk.We performed a case-control study nested in a community-based cohort (2013-2018, n = 16457). The study included 321 incident cases of IS and 321 controls matched by age and gender. Carnitine, lysine, trimethyllysine (TML), glycine, and their ratios were measured/calculated in the baseline plasma samples using ultra-high performance liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS). Conditional logistic regression analyses were used to calculate odds ratios (ORs) and their 95% confidence intervals (CIs).Plasma carnitine, lysine, TML, and glycine were not significantly associated with the IS risk, although a gradually reduced risk was observed across the increasing tertiles of glycine. Notably, the ratios of glycine/carnitine, glycine/lysine, and glycine/TML were all inversely associated with the IS risk. Compared to the lowest tertiles, the corresponding odds ratios for the highest tertiles were 0.60 (95% CI: 0.40-0.91), 0.63 (95% CI: 0.42-0.94), and 0.63 (95% CI: 0.42-0.95), respectively, after adjustment for body mass index, smoking, hypertension, family history of stroke, estimated glomerular filtration rate and total cholesterol. Repeating the analyses by excluding the first two years of follow-up did not materially alter the risk associations for the ratios of glycine/lysine and glycine/carnitine.Increased ratios of plasma glycine to carnitine, lysine, and TML were associated with a lower risk of incident IS. Our observational findings suggest that the homeostasis of circulating carnitine, lysine, TML, and glycine may involve in the pathogenesis of IS.

In this study, we used a network meta-analysis (NMA) to compare the effectiveness of medicines and supplements for idiopathic male infertility and to identify the best treatment. Medline, Excerpta Medica Database (EMBASE), Ovid, and China National Knowledge Infrastructure (CNKI), were searched for the period from January 1990 to June 2021 using the keywords “male infertility,” “medical therapy,” “supplement/nutrient therapy,” and related terms. Studies involving randomized controlled trials (RCTs) investigating medicines (mainly follicle-stimulating hormone (FSH), androgen, and clomiphene/tamoxifen) or supplements (mainly zinc, selenium, vitamin C or E, carnitine, coenzyme Q10 (CoQ10), or combined treatment) for idiopathic infertile men were selected for meta-analysis. Preferred reporting items for systematic reviews and meta-analysis (PRISMA) was used for data extraction, and a risk-of-bias tool and grades of recommendation, assessment, development, and evaluation (GRADE) system adapted to the NMA were employed to assess the quality of the evidence. The primary outcomes were live birth and spontaneous pregnancy rate (SPR). The secondary outcomes were sperm parameters (including concentration, progressive motility, and morphology) and side effects. In total, 65 RCTs involving 7541 men with sperm abnormalities but normal hormone levels were included. A total of 36 studies reported SPR but only three reported live birth rates. The quality of the included studies was found to be moderate to high. Compared with a placebo or being untreated, carnitine plus vitamins significantly improved SPR (relative risk (RR) = 3.7, 95% confidence interval (CI), 1.6–8.5); fatty acids significantly increased sperm concentrations (mean difference (MD) = 12.5 × 106 mL–1, 95%CI, 3.1 × 106–22.0 × 106); and selective estrogen receptor modulators (SERM) plus CoQ10 significantly improved sperm progressive motility (MD = 11.0%, 95%CI, 0.1%–21.9%) and normal sperm morphology (MD = 11.0%, 95%CI, 4.6%–17.4%). The most optimal intervention was carnitine plus vitamins and fatty acids for SPR and sperm concentrations, respectively, even after excluding trials at a high risk of bias. Compared with a placebo or being untreated, FSH (RR = 4.9, 95%CI, 1.1–21.3) significantly increased SPR, whereas SERM plus kallikrein increased sperm concentration (MD = 16.5 × 106 mL–1, 95%CI, 1.6 × 106–31.4 × 106), and SERM plus CoQ10 significantly improved sperm progressive motility (MD = 11.3%, 95%CI, 7.3%–15.4%) and normal morphology (MD = 11.2%, 95%CI, 5.4%–16.9%) in men with oligoasthenozoospermia (OA). In terms of side effects, fatty acids and pentoxifylline were associated with foul breath and/or a bad taste (RR = 8.1, 95%CI, 1.0–63.5) and vomiting (RR = 8.0, 95%CI, 1.0–63.0), respectively. In conclusion, the optimal treatment for male infertility for live birth is still unknown. Carnitine plus vitamins and FSH are likely to be better than other therapies in achieving successful spontaneous pregnancy in couples overall and in couples with men with OA, respectively. The efficacy of other treatments on pregnancy outcomes warrants further verification.

A 70-day feeding trial was conducted to investigate effects of dietary lysolecithin on growth performance, serum biochemical indexes, antioxidant capacity, lipid metabolism and inflammation-related genes expression of juvenile large yellow croaker (Larimichthys crocea) with initial weight of 6.04 ± 0.08 g. A formulated diet containing approximately 42% crude protein and 12.5% crude lipid was used as the control diet (CON). The other three experimental diets were formulated with supplementation of 0.2%, 0.4% and 0.6% lysolecithin based on the control diet, respectively. Results showed that weight gain rate (WGR) and specific growth rate (SGR) significantly increased in fish fed diets with lysolecithin compared with those in the control diet (P 0.05). Fish fed diets with 0.4% and 0.6% lysolecithin had notably higher lipid content in muscle than that in the control diet (P 0.05). When fish were fed diets with lysolecithin, serum high-density lipoprotein cholesterol (HDL-c) content was notably higher than that in the control diet (P 0.05), while fish fed the diet with 0.6% lysolecithin had a significant lower serum low-density lipoprotein cholesterol (LDL-c) content than that in the control diet (P 0.05). Meanwhile, serum aspartate transaminase (AST) and alanine transaminase (ALT) activities in fish fed diets with lysolecithin were remarkably lower than those in the control diet (P 0.05). With the increase of dietary lysolecithin from 0.2% to 0.6%, mRNA expression of stearoyl-coenzyme A desaturase 1 (scd1), diacylglycerol acyltransferase 2 (dgat2) and sterol-regulatory element binding protein 1 (srebp1) showed decreasing trends. Furthermore, mRNA expression of carnitine palmitoyl transferase 1 (cpt1) and lipoprotein lipase (lpl) among each dietary lysolecithin treatment were significantly higher than those in the control diet (P 0.05). In terms of inflammation, mRNA expression of tumor necrosis factor α (tnf-α) and interleukin-1 β (il-1β) were significantly down-regulated in fish fed diets with lysolecithin compared with those in the control diet (P 0.05), while the mRNA expression of interleukin-10 (il-10) was significantly higher than that in the control diet (P 0.05). In conclusion, dietary lysolecithin could promote the growth performance, improve hepatic lipid metabolism and regulate inflammation response in juvenile large yellow croaker, and the optimal supplement level of lysolecithin was approximately 0.4% in this study.

Mitochondrial toxicity resulting in myopathy and lactic acidosis has been described in antiretroviral (ARV)-exposed patients. We hypothesized that myopathy in HIV-infected, ARV-treated children would be associated with metabolic (acylcarnitines) and genetic (variants in metabolic genes) markers of dysfunctional fatty acid oxidation (FAO).Acylcarnitine profiles (ACP) were analyzed for 74 HIV-infected children on nucleoside reverse transcriptase inhibitor (NRTI)-containing ARV. Thirty-seven participants with ≥2 creatine kinase measurements500 IU (n = 18) or evidence of echocardiographic cardiomyopathy (n = 19) were matched with 37 participants without myopathy. Single nucleotide polymorphisms (SNPs) in FAO genes were also evaluated.Abnormal ACP was 73% (95% CI: 56%-86%) and 62% (95% CI: 45%-78%) in the myopathic and nonmyopathic groups, respectively. No significant association was found between myopathy and having an abnormal ACP (OR = 2.10, P = 0.22). In univariate analysis, a 1-year increase in NRTI use was associated with a 20% increase in odds of at least 1 ACP abnormality [OR (95% CI) = 1.20 (1.03-1.41); P = 0.02), and a 1-year increase in protease inhibitor use was associated with 28% increase in the odds of having at least 1 ACP abnormality [OR (95% CI) = 1.28 (1.07-1.52); P = 0.006). Three SNPs, all in the gene for the carnitine transporter ( SLC22A5 ), were associated with the cardiomyopathy phenotype.FAO appears to be altered in HIV-infected children with and without myopathy, but abnormal FAO does not fully explain myopathy in ARV-exposed children. Further study of SLC22A5 variation in ARV-exposed people is warranted carnitine transporter dysfunction-related cardiomyopathy may be treatable.

Twelve years following gastric bypass surgery, a cachectic 69-year-old woman presented with both fasting and postprandial hypoglycaemia. Postprandial symptoms were relieved by dietary modification and acarbose, as is common in such cases. During a supervised fast, symptomatic hypoglycaemia occurred. Concurrent laboratory testing showed suppression of plasma insulin, c-peptide, proinsulin and insulin-like growth factor II. However, beta-hydroxybutyrate was also low, surprising given insulin deficiency. Elevated plasma free fatty acid (FFA) concentrations suggested that lipolysis was not impaired, making cachexia/malnutrition a less likely cause of hypoglycaemia. The apparent diagnosis was failure to counter-regulate—subsequent plasma carnitine measurements showed carnitine deficiency which presumably prevented FFA transport across mitochondrial membranes for ketogenesis. Repletion with high-dose oral carnitine supplements effected resolution of fasting hypoglycaemia.

Background: Pancreatic cancer is the most common pancreatic solid malignancy with an aggressive clinical course and low survival rate. There are a limited number of reliable prognostic biomarkers and a need to understand the pathogenesis of pancreatic tumors; neuroendocrine (PNET) and pancreatic ductal adenocarcinomas (PDAC) encouraged us to analyze the serum metabolome of pancreatic tumors and disturbances in the metabolism of PDAC and PNET. Methods: Using the AbsoluteIDQ® p180 kit (Biocrates Life Sciences AG, Innsbruck, Austria) with liquid chromatography–mass spectrometry (LC-MS), we identified changes in metabolite profiles and disrupted metabolic pathways serum of NET and PDAC patients. Results: The concentration of six metabolites showed statistically significant differences between the control group and PDAC patients (p.adj < 0.05). Glutamine (Gln), acetylcarnitine (C2), and citrulline (Cit) presented a lower concentration in the serum of PDAC patients, while phosphatidylcholine aa C32:0 (PC aa C32:0), sphingomyelin C26:1 (SM C26:1), and glutamic acid (Glu) achieved higher concentrations compared to serum samples from healthy individuals. Five of the tested metabolites: C2 (FC = 8.67), and serotonin (FC = 2.68) reached higher concentration values in the PNET serum samples compared to PDAC, while phosphatidylcholine aa C34:1 (PC aa C34:1) (FC = −1.46 (0.68)) had a higher concentration in the PDAC samples. The area under the curves (AUC) of the receiver operating characteristic (ROC) curves presented diagnostic power to discriminate pancreatic tumor patients, which were highest for acylcarnitines: C2 with AUC = 0.93, serotonin with AUC = 0.85, and PC aa C34:1 with AUC = 0.86. Conclusions: The observations presented provide better insight into the metabolism of pancreatic tumors, and improve the diagnosis and classification of tumors. Serum-circulating metabolites can be easily monitored without invasive procedures and show the present clinical patients’ condition, helping with pharmacological treatment or dietary strategies.

Background: The carnitine/acylcarnitine carrier (CAC) represents the route of delivering acyl moieties to the mitochondrial matrix for accomplishing the fatty acid β-oxidation. The CAC has a couple of Cys residues (C136 and C155) most reactive toward ROS and redox signaling compounds such as GSH, NO, and H2S. Among physiological compounds reacting with Cys, itaconate is produced during inflammation and represents the connection between oxidative metabolism and immune responses. The possible interaction between the CAC and itaconate has been investigated. Methods: the modulatory effects of itaconate on the transport activity of the native and recombinant CAC were tested using the proteoliposome experimental model together with site-directed mutagenesis and computational analysis. Results: Itaconate reacts with the CAC causing irreversible inhibition. Dose–response experiment performed with the native and recombinant protein showed IC50 for itaconate of 11 ± 4.6 mM and 8.4 ± 2.9 mM, respectively. The IC50 decreased to 3.8 ± 1.0 mM by lowering the pH from pH 7.0 to pH 6.5. Inhibition kinetics revealed a non-competitive type of inhibition. C136 is the main target of itaconate, as demonstrated by the increased IC50 of mutants in which this Cys was substituted by Val. The central role of C136 was confirmed by covalent docking. Administration of dimethyl itaconate to HeLa cells inhibited the CAC transport activity, suggesting that itaconate could react with the CAC also in intact cells.

We present five new sorbents for the evaluation of the pre-concentration of L-carnitine. The sorbents were obtained from copolymerization between butylmethacrylate (BuMA) and ethylene dimethacrylate (EDMA), which were physically modified on their surface by each one of the five synthetized resorcinarenes of variable chain length studied, with long-chain resorcinarenes exhibiting better fixation on the copolymer. The characterization of the synthesized resorcinarenes was done using FTIR-ATR, 1H NMR, 13C NMR, and mass spectrometry, while characterization of the sorbents was done using FTIR-ATR and scanning electron micrography (SEM). The molecular interaction between L-carnitine and the synthesized resorcinarenes was studied in DMSO via 1H-NMR spectroscopy and, in the gas phase, via electrospray ionization-mass spectrometry (ESI-MS). The results showed that the short-chain resorcinarenes underwent a stable interaction with the neurotransmitter. Once the sorption of resorcinarenes on the copolymer was accomplished, the best parameters for the evaluation of the L-carnitine preconcentration were established. The solution tests were carried out through LC/MS analysis, obtaining better results for L-carnitine absorption with the short-chain resorcinarenes such as tetra(ethyl)calix[4]resorcinarene and tetra(propyl)calix[4]resorcinarene.

Drug-induced liver injury (DILI) is a rare but serious adverse event that can progress to acute liver failure (ALF). The evidence for treatment of DILI in children is scarce. We aimed to comprehensively review the available literature on the therapies for both acetaminophen overdose (APAP) and idiosyncratic DILI in the paediatric population. We included original articles conducted in a paediatric population ( Overall, 25 publications (fifteen case reports, six case series and four retrospective cohort studies) were included, including a total of 140 paediatric DILI cases, from preterm newborn neonates to adolescents. N-acetylcysteine was used to treat 19 APAP cases. N-acetylcysteine (n = 14), ursodeoxycholic acid (n = 3), corticosteroids (n = 31), carnitine (n = 16) and the combination of glycyrrhizin, reduced glutathione, polyene phosphatidylcholine and S-adenosylmethionine (n = 31) were the therapeutic options for treating idiosyncratic DILI. The molecular adsorbent recirculating system was used in the management of either APAP (n = 4) or idiosyncratic DILI (n = 2), while 20 paediatric ALF cases received continuous renal replacement therapy. This systematic review identified DILI in the paediatric population who have received specific treatment. These interventions appear to be mainly extrapolated from low-quality evidence from the adult population. Thus, there is a need for high-quality studies to test the efficacy of known and novel therapies to treat DILI specifically addressed to the paediatric population. PROSPERO registration number CRD42021214702.

Trimethylamine lyases are expressed in a wide range of intestinal microbiota which metabolize dietary nutrients like choline, betaine, and L-carnitine to form trimethylamine (TMA). Trimethylamine N-oxide (TMAO) is an oxidative product of trimethylamine (TMA) catalyzed by the action of flavin monooxygenases (FMO) in the liver. Higher levels of TMAO in the plasma and cerebrospinal fluid (CSF) have been shown to contribute to the development of risk factors and actively promote the pathogenesis of metabolic, cardiovascular, and cerebrovascular diseases. The investigations on the harmful effects of TMAO in the development and progression of neurodegenerative and sleep disorders are summarized in this manuscript. Clinical investigations on the role of TMAO in predicting risk factors and prognostic factors in patients with neurological disorders are also summarized. It is observed that the mechanisms underlying TMAO-mediated pathogenesis include activation of inflammatory signaling pathways such as nuclear factor kappa B (NF-κβ), NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome, and MAPK/JNK in the periphery and brain. Data suggests that TMAO levels increase with age-related cognitive dysfunction and also induce mitochondrial dysfunction, oxidative stress, neuronal senescence, and synaptic damage in the brain. Further research into the relationships between dietary food consumption and gut microbiota-dependent TMAO levels could provide novel therapeutic options for neurological illnesses.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease that leads rapidly to death. The present study is aimed at discovering the in-depth pathogenesis of IPF, exploring the role of adiponectin/carnitine palmityl transferase 1A- (APN/CPT1A-) mediated fatty acid metabolism during the development of IPF, and excavating its potential mechanism. Here, THP-1 cells were differentiated into M0 macrophages, followed by polarization to M1 macrophages upon hypoxia. Subsequently, lung fibroblast HFL-1 cells were stimulated by M1 macrophages to simulate hypoxia-related IPF condition in vitro. It was discovered that the stimulation of M1 macrophages promoted fibroblast proliferation and fibrosis formation in vitro, accompanied with a disorder of the APN/CPT1A pathway, an overproduction of lipid peroxides, and a low level of autophagy in HFL-1 cells. Thereafter, APN treatment or CPT1A overexpression greatly suppressed above lipid peroxide accumulation, fibroblast proliferation, and fibrosis but activated autophagy in vitro. Furthermore, an in vivo IPF rat model was established by injection of bleomycin (BLM). Consistently, CPT1A overexpression exerted a protective role against pulmonary fibrosis in vivo; however, the antifibrosis property of CPT1A was partly abolished by 3-methyladenine (an autophagy inhibitor). In summary, APN/CPT1A-mediated fatty acid metabolism exerted its protective role in IPF partly through activating autophagy, shedding a new prospective for the treatment of IPF.

Postmenopausal women are at increased risk of developing coronary artery disease (CAD). Metabolomic approaches aim at discovering more helpful biomarkers of CAD to reduce the disease burden in the future. Here, we intend to find potential blood biomarkers, amino acids, and acylcarnitines in postmenopausal women with different severity of CAD by using high-throughput methods.This cross-sectional study was performed on postmenopausal women ( n = 183) who underwent coronary CT scans. Coronary artery calcium scoring (CACS) was assessed to detect plaque burden and degree of coronary artery obstruction. The participants were divided into three groups based on the score as follows (i) "low CACS" ( n = 96); a score of 0 to 10, (ii) "medium CACS" ( n = 35); a score between 11 and 100 and (iii) "high CACS" ( n = 52); a score greater than 100. Metabolites, including amino acids and acylcarnitines, were quantified using a targeted mass spectrometry method in serum samples. The association between metabolites and disease status was evaluated using univariate and multivariate regression analyses with adjustment for confounding factors. Factor analysis was used to deal with multiple comparisons.Metabolites, including proline, glutamic acid, and phenylalanine, were significantly lower in the high CACS group than the low CACS one. Also, a lower level of lysine and phenylalanine in high CACS compared with medium one was observed. Concerning acylcarnitines, it was found that C4 and C8:1 significantly were higher in women with high CACS. The logistic regression analysis revealed that the circulating levels of these metabolites (except C4) were associated with the presence of coronary artery calcification independently of age, body mass index, and time of menopause. Also, the amino acids were associated independently of medication and diabetes.The present study indicated that circulating levels of amino acids and acylcarnitines profile in postmenopausal women are partly associated with the severity of CAD in these participants.

Propofol and dexmedetomidine (DEX) are widely used for anesthesia and sedation. We investigated the effects of propofol and DEX separately and in combination on the metabolic profile of carnitine in cultured normal human bronchial epithelial cells (BEAS-2B). Cells of the propofol group were cultured with 2 µg/ml propofol in RPMI-1640 medium. Cells of the DEX group were cultured with 0.2 ng/m DEX in RPMI-1640 medium. Cells of the propofol + DEX group were cultured with 2 μg/ml propofol + 0.2 ng/ml DEX in RPMI-1640 medium. The control group was untreated. Cells were incubated for 3 h following treatments. The effects of the drugs on cell viability were assessed using the MTT method and by microscopic examination following staining with acridine orange/ethidium bromide. The effects of drugs on carnitine, acetyl carnitine and 25 acylcarnitine derivative profiles were analyzed using liquid chromatography-tandem mass spectrophotometry. Neither propofol nor DEX affected cell viability. Administration of propofol, DEX or propofol + DEX to BEAS-2B cells caused no significant change in the concentrations of carnitine and acylcarnitine derivatives compared to the control group. We found that propofol and DEX exhibit no negative effects on the carnitine metabolism by BEAS-2B cells in vitro at clinically relevant concentrations. Our findings establish a baseline for clinical studies of the effects of propofol and DEX on carnitine metabolism.

Continuous renal replacement therapy (CRRT) is essential to the management of acute kidney injury (AKI) in critical illness. Unfortunately, large quantities of micronutrients are shown to be lost in CRRT effluent. Current literature describes serum micronutrient values in CRRT patients to be below-reference range, yet seldom compares such values to other critically ill populations unexposed to CRRT. The aim of this study was to describe and compare the prevalence of micronutrient and carnitine deficiencies in critically ill patients at high malnutrition risk exposed to CRRT to a group of patient unexposed to CRRT.A retrospective chart review was conducted at Duke University Hospital using the electronic medical record. The study group consisted of patients at high malnutrition risk requiring intensive care unit (ICU) admission from 01/01/2017-12/31/2018 with one or more of the following serum micronutrient levels checked: carnitine, copper, zinc, selenium, and vitamins B1, B6, B9, and C. Micronutrient deficiencies were defined as below the reference range and carnitine deficiencies were interpreted as an acyl to free carnitine ratio (ACFR) of0.4.106 ICU patients met inclusion criteria and 46% were exposed to CRRT. At least one micronutrient deficiency was reported in 90% of CRRT patients compared to 61% patients unexposed to CRRT (p = 0.002). A greater percentage of copper (p 0.001) and carnitine (p 0.001) deficiencies were found among patients exposed to CRRT, while more zinc deficiencies were noted among non-CRRT patients (p = 0.001).The vast majority of CRRT patients presented with micronutrient deficiencies. Clinicians should have a heightened awareness of the risk for serum copper, carnitine, and vitamin B6 deficiencies among CRRT patients. Further prospective and randomized-controlled trials are needed to better define this new category of malnutrition and test supplementation strategies to address and prevent these clinically-relevant deficiencies.

Idiopathic inflammatory myopathies (IIM) are a class of autoimmune diseases with high heterogeneity that can be divided into different subtypes based on clinical manifestations and myositis-specific autoantibodies (MSAs). However, even in each IIM subtype, the clinical symptoms and prognoses of patients are very different. Thus, the identification of more potential biomarkers associated with IIM classification, clinical symptoms, and prognosis is urgently needed.Plasma and urine samples from 79 newly diagnosed IIM patients (mean disease duration 4 months) and 52 normal control (NC) samples were analysed by high-performance liquid chromatography of quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS)/MS-based untargeted metabolomics. Orthogonal partial least-squares discriminate analysis (OPLS-DA) were performed to measure the significance of metabolites. Pathway enrichment analysis was conducted based on the KEGG human metabolic pathways. Ten machine learning (ML) algorithms [linear support vector machine (SVM), radial basis function SVM, random forest, nearest neighbour, Gaussian processes, decision trees, neural networks, adaptive boosting (AdaBoost), Gaussian naive Bayes and quadratic discriminant analysis] were used to classify each IIM subtype and select the most important metabolites as potential biomarkers.OPLS-DA showed a clear separation between NC and IIM subtypes in plasma and urine metabolic profiles. KEGG pathway enrichment analysis revealed multiple unique and shared disturbed metabolic pathways in IIM main [dermatomyositis (DM), anti-synthetase syndrome (ASS), and immune-mediated necrotizing myopathy (IMNM)] and MSA-defined subtypes (anti-Mi2+, anti-MDA5+, anti-TIF1γ+, anti-Jo1+, anti-PL7+, anti-PL12+, anti-EJ+, and anti-SRP+), such that fatty acid biosynthesis was significantly altered in both plasma and urine in all main IIM subtypes (enrichment ratio 1). Random forest and AdaBoost performed best in classifying each IIM subtype among the 10 ML models. Using the feature selection methods in ML models, we identified 9 plasma and 10 urine metabolites that contributed most to separate IIM main subtypes and MSA-defined subtypes, such as plasma creatine (fold change = 3.344, P = 0.024) in IMNM subtype and urine tiglylcarnitine (fold change = 0.351, P = 0.037) in anti-EJ+ ASS subtype. Sixteen common metabolites were found in both the plasma and urine samples of IIM subtypes. Among them, some were correlated with clinical features, such as plasma hypogeic acid (r = -0.416, P = 0.005) and urine malonyl carnitine (r = -0.374, P = 0.042), which were negatively correlated with the prevalence of interstitial lung disease.In both plasma and urine samples, IIM main and MSA-defined subtypes have specific metabolic signatures and pathways. This study provides useful clues for understanding the molecular mechanisms, searching potential diagnosis biomarkers and therapeutic targets for IIM.

Human Carnitine Acetyl Transferase (hCAT) reversibly catalyzes the transfer of the acetyl-moiety from acetyl-CoA to L-carnitine, modulating the acetyl-CoA/CoA ratio in mitochondria. Derangement of acetyl-CoA/CoA ratio leads to metabolic alterations that could result in the onset or worsening of pathological states. Due to the importance of CAT as a pharmacological target and to the European directive for reducing animal experimentation, we have pointed out a procedure to produce a recombinant, pure, and functional hCAT using the E. coli expression system. The cDNA encoding for the hCAT was cloned into the pH6EX3 vector. This construct was used to transform the E. coli Rosetta strain. The optimal conditions for the overexpression of the fully active hCAT include induction with a low concentration of IPTG (0.01 mM) and a low growth temperature (25 °C). The recombinant protein was purified from bacterial homogenate by affinity chromatography. The pure hCAT is very stable in an aqueous solution, retaining full activity for at least two months if stored at − 20 °C. These results could be helpful for a broad set of functional studies on hCAT, including drug-design applications.

Acylcarnitines are fatty acid metabolites that play important roles in many cellular energy metabolism pathways. They have historically been used as important diagnostic markers for inborn errors of fatty acid oxidation and are being intensively studied as markers of energy metabolism, deficits in mitochondrial and peroxisomal b-oxidation activity, insulin resistance, and physical activity. Acylcarnitines are increasingly being identified as important indicators in metabolic studies of many diseases, including metabolic disorders, cardiovascular diseases, diabetes, depression, neurologic disorders, and certain cancers. The US Food and Drug Administration-approved drug L-carnitine, along with short-chain acylcarnitines (acetylcarnitine and propionylcarnitine), is now widely used as a dietary supplement. In light of their growing importance, we have undertaken an extensive review of acylcarnitines and provided a detailed description of their identity, nomenclature, classification, biochemistry, pathophysiology, supplementary use, potential drug targets, and clinical trials. We also summarize these updates in the Human Metabo lome Database, which now includes information on the structures, chemical formulae, chemical/spectral properties, descriptions, and pathways for 1240 acylcarnitines. This work lays a solid foundation for identifying, characterizing, and understanding acylcarnitines in human biosamples. We also discuss the emerging opportunities for using acylcarnitines as biomarkers and as dietary interventions or supplements for many wide-ranging indications. The opportunity to identify new drug targets involved in controlling acylcarnitine levels is also discussed. Significance Statement--This review provides a comprehensive overview of acylcarnitines, including their nomenclature, structure and biochemistry, and use as disease biomarkers and pharmaceutical agents. We present updated information contained in the Human Metabolome Database website as well as substantial mapping of the known biochemical pathways associated with acylcarnitines, thereby providing a strong foundation for further clarification of their physiological roles.

The opportunistic human pathogen Acinetobacter baumannii can grow with carnitine but its metabolism, regulation and role in virulence remained elusive. Recently, we identified a carnitine transporter encoded by a gene closely associated with potential carnitine degradation genes. Among those is a gene coding for a putative d-malate dehydrogenase (Mdh). Deletion of the mdh gene led to a loss of growth with carnitine but not l-malate; growth with d-malate was strongly reduced. Therefore, it is hypothesized that d-malate is formed during carnitine oxidation and further oxidized to CO

Only a few studies have explored the role of microbiota-dependent metabolite trimethylamine N-oxide (TMAO) in non-complicated pregnancy and in pre-eclampsia (PE). We enrolled 139 PE and 29 healthy pregnant women in a nested case control study. We hypothesized that elevated levels of circulating TMAO and its precursors choline and glycine betaine in the late second or in third trimester might contribute to the PE and are associated with the onset of the disease and clinical features such as elevated blood pressure. The association with a few available lifestyle factors (use of fish and physical activity) was also evaluated. In contrast with the previous findings, there was no difference in TMAO concentration between PE and healthy women. In addition, TMAO concentration was not associated with any of the PE related clinical features, angiogenic or inflammatory markers. In future, it is crucial to obtain longitudinal data on TMAO in both non-complicated and in PE pregnancies before we could have more detailed understanding of TMAO. publishedVersion

Carnitine deficiency and impaired glucose tolerance (IGT) exacerbate liver steatosis. Given the current lack of ideal murine nonalcoholic steatohepatitis (NASH) models, we investigated new NASH models using jvs/+ mice with low carnitine and wild-type mice with low-dose alloxan-induced IGT. The jvs/+ and wild-type mice were divided into jvs/+ mice fed a high-fat diet (HFD) from 3 weeks of age (HF hetero group), wild-type mice with low-dose alloxan treatment fed HFD (AL + HF wild group), wild-type mice fed HFD (HF wild group), and two types of mice fed a normal diet-jvs/+ and wild-type (intact group). All mice were sacrificed at 20 or 40 weeks of age. All male HFD-fed mice showed obesity, IGT, high blood insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR), high liver enzyme levels, and high cholesterol levels. The degree of IGT was the worst in the AL + HF wild group, and blood insulin levels and HOMA-IR score were remarkably increased from 20 to 40 weeks of age. Almost all HFD-fed mice showed steatosis, fibrosis, and lobular inflammation in the centrilobular zone. These changes were accompanied by hepatocyte ballooning and were enhanced at 40 weeks of age. Furthermore, the incidence rate of nodular hyperplasia and adenoma in both the HF hetero and AL + HF wild groups was nearly 30%. We successfully established two novel murine models of NASH using male jvs/+ mice with low carnitine and male wild-type mice with IGT that eventually developed obesity, fatty liver, insulin resistance, liver fibrosis, and tumorigenesis. These results suggest that low carnitine levels and early-stage induction of IGT are important factors in the progression of NASH to tumorigenesis, similar to human NASH.

Critical ill patients experience catabolic stress, which results in a systemic inflammatory response. The inflammatory response is associated with increased complications, including infection, multi-organ dysfunction, increased length of ICU stays, and mortality. l-Carnitine supplementation may play an important role in these patients by regulating inflammatory cell function. The purpose of the present study was to investigate the effect of l-Carnitine supplementation on clinical status, inflammatory markers, and mortality rate in critically ill patients admitted to the intensive care unit (ICU).This randomized, double-blind, placebo-controlled trial was performed on critically ill patients. Subjects were randomly assigned into placebo (n = 27) and l-Carnitine (n = 27) groups. l-Carnitine (3000 mg/day) was administered via nasogastric tube for the intervention group for 7 days, while the other group received a placebo for the same duration. Serum levels of inflammatory markers, including C-reactive protein (CRP) and interleukin-6 (IL-6) were measured. Nutritional status and the acute physiology and chronic health evaluation (APACHE) score, sequential organ failure assessment (SOFA) score, and 28-day mortality were also recorded.Fifty-one critically ill patients completed the study. l-Carnitine supplementation significantly reduced the levels of CRP (mean change ± SE: -34.9 ± 6.5) and IL-6 (mean change ± SE: -10.64 ± 2.16) compared to the baseline, which is both statistically significant compared with the control group (p 0.05). The SOFA and APACHE scores were significantly reduced in the l-Carnitine group compared with the placebo group (p = 0.02 and p 0.001, respectively).l-Carnitine supplementation showed beneficial effects on inflammatory and clinical outcomes of critically ill patients.Trial registration: IRCT, Registered 30 May 2018, https://www.irct.ir/trial/30748.

In this review, we discussed the biological targets of carnitine, its effects on immune function, and how L-carnitine supplementation may help critically ill patients. L-carnitine is a potent antioxidant. L-carnitine depletion has been observed in prolonged intensive care unit (ICU) stays, while L-carnitine supplementation has beneficial effects in health promotion and regulation of immunity. It is essential for the uptake of fatty acids into mitochondria. By inhibiting the ubiquitin-proteasome system, down-regulating the apelin receptor in cardiac tissue, and reducing β-oxidation of fatty acid, carnitine may decrease vasopressor requirement in septic shock and improve clinical outcomes of this group of patients. We also reviewed animal and clinical studies that have been recruited for evaluating the beneficial effects of L-carnitine in the management of sepsis/ septic shock. Additional clinical data are required to evaluate the optimal daily dose and duration of L-carnitine supplementation.

This study aimed to evaluate the effectiveness of unprotected and rumen-protected L-carnitine through in vitro tests, rumen degradation tests, and in vivo tests. Twelve rumen-fistulated crossbred rams with similar body weights of 55 ± 3.6 kg and ages of 3 ± 0.2 yr old were divided into three treatment groups in a 3 × 3 Latin square design, G1 (basal diet with no additives), G2 (unprotected L-carnitine), or G3 (rumen-protected L-carnitine). Ruminal fluid and blood samples were collected before morning feeding on the last day of each experimental period (21 d). The percentage of L-carnitine remaining in the simulated rumen and abomasum and rumen increased with the increase in the wall material ratio (P

Circadian rhythmicity in renal function suggests rhythmic adaptations in renal metabolism. To decipher the role of the circadian clock in renal metabolism, we studied diurnal changes in renal metabolic pathways using integrated transcriptomic, proteomic, and metabolomic analysis performed on control mice and mice with an inducible deletion of the circadian clock regulator Bmal1 in the renal tubule (cKOt). With this unique resource, we demonstrated that approximately 30% of RNAs, approximately 20% of proteins, and approximately 20% of metabolites are rhythmic in the kidneys of control mice. Several key metabolic pathways, including NAD+ biosynthesis, fatty acid transport, carnitine shuttle, and β-oxidation, displayed impairments in kidneys of cKOt mice, resulting in perturbed mitochondrial activity. Carnitine reabsorption from primary urine was one of the most affected processes with an approximately 50% reduction in plasma carnitine levels and a parallel systemic decrease in tissue carnitine content. This suggests that the circadian clock in the renal tubule controls both kidney and systemic physiology.

Background: The sciatic nerve is a peripheral nerve and is more vulnerable to compression with subsequent short- or long-term neuronal dysfunction. The current study was designed to elucidate the possible ameliorative effect of L-carnitine and sildenafil (SIL) on sciatic nerve crush injury. We sought to determine the effects of L-carnitine, a neuroprotective and a neuro-modulatory agent, and sildenafil citrate, a selective peripheral phosphodiesterases inhibitor on modulating neuro-degenerative changes due to sciatic nerve compression. Materials and methods: The comparative effect of L-carnitine (at an oral dose of 20 mg/kg/day) or SIL citrate (20 mg/kg/day orally) administration for 21 days was studied in a rat model of sciatic nerve compression. Sciatic nerve sections were subjected to biochemical, histological, ultrastructure, and immunohistochemical studies to observe the effects of these treatments on neurofilament protein. Results: The sciatic nerve crush injury group (group II) showed a significant decrease in tissue catalase (CAT), superoxide dismutase (SOD) and increase in malondhyde (MDA) as compared to control group (P < 0.01). Histological changes in the form of degenerated and vacuolated axoplasm with areas of nerve fiber loss and pyknotic nuclei were reported. The blood vessels were dilated, congested with areas of hemorrhage and mononuclear cell infiltration. Histo-morphometrically, a statistically significant reduction in the nerve fibers number, mean axon cross-sectional area, myelin sheath thickness and a significant increase in collagen fibers percentage (P < 0.05) as compared to control group. Immunohistochemically, neurofilament protein was significantly downregulated as proved by a significant reduction in mean area % of neurofilament expression. L-carnitine ameliorated the studied parameters through it`s neuroprotective effect while Sildenafil (SIL) is a selective peripheral phosphodiesterases (PDE-5) inhibitor had improved crush injury parameters but with less extent than L-carnitine. Conclusions: These findings indicate the valuable effects of L-carnitine administration compared to that of SIL citrate in alleviating the serious debilitating effects of sciatic nerve crush injury. Our results provide a new insight into the scope of neuroprotective and, neuro-regenerative effects of L-carnitine in a sciatic nerve compression model.

Purpose. L-carnitine (LC) is considered to have good therapeutic potential for myocardial infarction (MI), but its mechanism has not been clarified. The aim of the study is to elucidate the cardioprotective effects of LC in mice following MI and related mechanisms. Methods. ICR mice were treated with LC for 2 weeks after induction of MI with ligation of left anterior descending artery. Electrocardiographic (ECG) recording and echocardiography were used to evaluate cardiac function. H&E staining, TTC staining, and Masson staining were performed for morphological analysis and cardiac fibrosis. ELISA and immunofluorescence were utilized to detect biomarkers and inflammatory mediators. The key proteins in the Bax/Bcl-2 signaling pathway were also examined by Western blot. Results. Both echocardiography and histological measurement showed an improvement in cardiac function and morphology. Biomarkers such as LDH, NT-proBNP, cTnT, and AST, as well as the inflammatory cytokines IL-1β, IL-6, and TNF-α, were decreased in plasma of mice receiving LC treatment after myocardial injury. In addition, the expression of α-SMA as well as the key proteins in the Bax/Bcl-2 signaling pathway in cardiac myocardium were much lower in mice with LC treatment compared to those without after MI. Conclusions. Our data suggest that LC can effectively ameliorate left ventricular (LV) remodeling after MI, and its beneficial effects on myocardial function and remodeling may be attributable at least in part to anti-inflammatory and inhibition of the Bax/Bcl-2 apoptotic signaling pathway.

l-Carnitine supplementation is effective in improving muscle cramps, hyperammonemia, and hepatic encephalopathy in patients with cirrhosis. However, limited evidence is available on the effect of l-carnitine supplementation on the survival of patients with cirrhosis.In this retrospective study, 674 patients with cirrhosis admitted to Gifu University Hospital or Chuno Kosei Hospital between October 2011 and December 2018 were enrolled. l-carnitine supplementation was defined as the use of l-carnitine for30 consecutive days during the follow-up period. Propensity score matching was applied to create comparable groups between l-carnitine-treated and untreated patients. Mortality was evaluated using the Cox proportional hazards model.Among the patients, 93 were excluded. Of the remaining 581 patients, 71 (12%) received l-carnitine supplementation. Propensity matching identified 189 patients (63 l-carnitine-treated and 126 untreated patients) with comparable baseline characteristics in both groups. Of the matched patients, 33 (52%) l-carnitine-treated and 74 (59%) untreated patients died during the median follow-up period of 36.3 months. Overall survival was significantly higher in l-carnitine-treated patients than in untreated patients (hazard ratio [HR], 0.66; 95% CI, 0.43-0.99). A subgroup analysis showed that the survival benefit of l-carnitine supplementation was prominent in patients with Child-Pugh Class B or C (HR, 0.39; 95% CI, 0.23-0.68), serum albumin levels ≤3.5 g/dl (HR, 0.59; 95% CI, 0.37-0.95), and ammonia levels ≥90 mcg/dl (HR, 0.50; 95% CI, 0.26-0.97), and in those without sarcopenia (HR, 0.56; 95% CI, 0.35-0.90).l-Carnitine supplementation may improve survival in patients with cirrhosis.

This is the first report of conducting proof-of-concept study for amperometric acetyltransferase-based L-carnitine sensor by employing the thiol/disulfide exchange reaction. The carnitine acetyltransferase (CrAT) catalyzes the reaction between acetyl-CoA and L-carnitine to produce CoA which is difficult to detect directly by electrochemical methods owing to steric hindrance and electrostatic effect of CoA. The thiol/disulfide exchange reaction between CoA and cystamine was mediated in the enzymatic reaction to produce electrochemically detectable low molecular weight of cationic cysteamine. The sensor exhibited high sensitivity and selectivity for L-carnitine in the concentration range 0.28-50 µM with a limit of detection of 0.28 µM. This is a promising strategy for L-carnitine sensing in point-of-care testing applications.

Obesity in pregnant women causes fetal cardiac dysfunction and increases offspring cardiovascular disease risk, but its effect on myocardial metabolism is unknown. We hypothesized that maternal obesity alters fetal cardiac expression of metabolism-related genes and shifts offspring myocardial substrate preference from glucose towards lipids. Female mice were fed control or obesogenic diets before and during pregnancy. Fetal hearts were studied in late gestation (embryonic day (E) 18.5; term ≈ E21), and offspring were studied at 3, 6, 9 or 24 months postnatally. Maternal obesity increased heart weight and peroxisome proliferator activated receptor gamma (Pparg) expression in female and male fetuses and caused left ventricular diastolic dysfunction in the adult offspring. Cardiac dysfunction worsened progressively with age in female, but not male, offspring of obese dams, in comparison to age-matched control animals. In 6-month-old offspring, exposure to maternal obesity increased cardiac palmitoyl carnitine-supported mitochondrial respiration in males and reduced myocardial

Context Ovarian tissue transplantation is performed to preserve fertility in patients undergoing chemotherapy and radiotherapy. However, the ischemia-reperfusion injury which occurs after the ovarian tissue transplantation causes follicular depletion and apoptosis. l-Carnitine has antioxidant and anti-inflammation properties. Aims Therefore, we aimed to investigate the beneficial effect of l-carnitine on mouse ovaries following heterotopic autotransplantation. Methods Mice were randomly divided into three groups (six mice per group): control, autografted and autografted + l-carnitine (200 mg/kg daily intraperitoneal injections). Seven days after ovary autografting, the serum levels of malondialdehyde (MDA), total antioxidant capacity, tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-10 were measured. Ovary histology, serum concentrations of progesterone and estradiol were also measured 28 days after autotransplantation. Data were analysed using one-way analysis of variance (ANOVA) and Tukey test, and the means were considered significantly different at P

A novel pathophysiological model of interest is the association between heart failure (HF) and the gastrointestinal system, the 'gut hypothesis'. The choline and carnitine metabolic by-product, Trimethylamine N-oxide (TMAO) is one of the more prominent molecules associated with the link between HF and the gut. Indeed, TMAO levels are increased in HF populations and higher TMAO levels are associated with poor prognosis, whereas low TMAO levels either at baseline/follow up confer better prognosis. Considering that TMAO levels seem not to be affected by guideline-HF treatment, this model could represent a novel and independent therapeutic target for HF.

Objectives: To analyze the effect in the blood metabolome of trail running, a demanding sport that takes place in the natural environment, places considerable strain on both muscles and joints. While metabolic responses to aerobic exercise have been analyzed in-depth, few studies have focused on trail running. Design: Observational study to analyze changes in 35 different metabolites - representative of aerobic exercise- induced by a simulated 21-km trail race with an uphill gradient of 1400 m. Methods: We performed a semiquantitative metabolomics study consisting of capillary blood microsampling and targeted screening with liquid chromatography and mass spectrometry to analyze, in 33 licensed athletes, changes concerning 35 metabolites. Results: We observed significant changes in many metabolites, including increased acetyl-carnitine and taurine concentrations (false discovery rate–corrected paired t-test P value 1.63 × 10–13, and P value 5.021 × 10-12, re- spectively) and decreased carnitine and proline concentrations (P value 6.33 × 10–10, and P value 1.21 × 10–9, re- spectively). Metabolic responses to trail running were largely independent of sex but were influenced by the level of training, with runners with a higher level showing resistance to exercise-induced changes in taurine, 1-methyl histidine, acetyl-carnitine, and hypoxanthine concentrations. Performance (measured as race time) was inversely correlated with changes in specific metabolites (including taurine, serotonin, and hypoxanthine) and directly correlated with increases in glutathione. Conclusions: Our findings demonstrate the usefulness of metabolomics studies for analyzing exercise-induced physiological changes and show individual differences associated with the level of training and performance. This work was supported by the Generalitat de Catalunya, Agency for Management of University and Research Grants [2017SGR696]; by the Spanish Ministry of Economy and Competitiveness, Institute of Health Carlos III [PI17-00134 and PI20-00155]; and by the Spanish Ministry of Science, Innovation and Universities [RTI2018-099200-B-I00]. MJ is a Serra-Hunter program fellow. AF is a fellow of Banco de Santander-UdL predoctoral program. We are also grateful for the support of; the National Institute of Physical Education of Catalonia (INEFC); and the Spanish government subproject Integration ways between qualitative and quantitative data, multiple case development, and synthesis review as main axis for an innovative future in physical activity and sports research [PGC2018-098742-B-C31] (2019–2021) (Ministry of Science, Innovation and Universities/Spanish State Research Agency/European Regional Development Fund), that is part of the coordinated project New approach of research in physical activity and sport from mixed methods perspective (NARPAS_MM) [SPGC201800X098742CV0]; and the Generalitat de Catalunya Research Group [Research group and innovation in designs] (GRID). Technology and multimedia and digital application to observational designs [Grant number 2017 SGR 1405]. FEDER funds are acknowledged [“A way to build Europe”].

Golden Retriever dogs with a frameshift variant in CLN5 (c.934_935delAG) suffer from a progressive neurodegenerative disorder analogous to the CLN5 form of neuronal ceroid lipofuscinosis (NCL). Five littermate puppies homozygous for the deletion allele were identified prior to the onset of disease signs. Studies were performed to characterize the onset and progression of the disease in these dogs. Neurological signs that included restlessness, unwillingness to cooperate with the handlers, and proprioceptive deficits first became apparent at approximately 12 months of age. The neurological signs progressed over time and by 21 to 23 months of age included general proprioceptive ataxia, menace response deficits, aggressive behaviors, cerebellar ataxia, intention tremors, decreased visual tracking, seizures, cognitive decline, and impaired prehension. Due to the severity of these signs, the dogs were euthanized between 21 and 23 months of age. Magnetic resonance imaging revealed pronounced progressive global brain atrophy with a more than sevenfold increase in the volume of the ventricular system between 9.5 and 22.5 months of age. Accompanying this atrophy were pronounced accumulations of autofluorescent inclusions throughout the brain and spinal cord. Ultrastructurally, the contents of these inclusions were found to consist primarily of membrane-like aggregates. Inclusions with similar fluorescence properties were present in cardiac muscle. Similar to other forms of NCL, the affected dogs had low plasma carnitine concentrations, suggesting impaired carnitine biosynthesis. These data on disease progression will be useful in future studies using the canine model for therapeutic intervention studies.

Background: Post-traumatic stress disorder (PTSD) is a genuine obstructing mental disorder. As indicated by the name, it is related to the patients’ stress augmented by life-threatening conditions or accidents. The PTSD has linked to oxidative stress that can result in neurodegeneration. L-carnitine (L-CAR) is known for its antioxidant properties, which can protect against neuronal damage. Objective: In the current study, we investigated the beneficial effects of L-CAR on the memory impairment induced by PTSD using a rat model. Methods: A model of single-prolonged stress (a cycle of restraining, forced swimming, rest, and finally diethyl ether exposure for 2 h, 20 min, 15 min, and 1–2 min, respectively) was used to induce PTSD-like behavior. Intraperitoneal L-CAR treatment (300 mg/kg/day) was introduced for four weeks. Both memory and special learning were evaluated utilizing the radial arm water maze (RAWM). Moreover, the levels of glutathione peroxidase (GPx), glutathione reduced (GSH), and glutathione oxidized (GSSG) were assessed as biomarkers oxidative stress in the hippocampus. Results: The results demonstrated that both the short and long-term memories were impaired by PTSD/SPS model (P

To study the effect of 3 antioxidants viz. selenium, carnitine and coenzyme Q10, alone or in combination, on both semen parameters and pregnancy rates in couples with male factor infertility.Using PRISMA guidelines, a systematic search was performed of the PubMed, Scopus, EMBASE, and Web of Science databases for randomized studies comparing selenium, carnitine or coenzyme Q10 with placebo in the treatment of male infertility and reporting semen and pregnancy outcomes.A total of 3304 studies were screened of which 20 were included. The study protocol was registered with PROSPERO (CRD42020210284). Pregnancy rate in the treatment group (69/426, 16.2%) was not different from the placebo (45/401, 11.2%) (P = .05). Treatment group showed higher motility [mean difference 5.05, 95% CI (2.77, 7.34), P =.0001], progressive motility [mean difference 5.72, 95% CI (2.77, 8.66), P = .0001], sperm concentration [mean difference 6.58, 95% CI (3.22, 9.93), P = .0001] than placebo.Although antioxidants and their combinations are associated with improvement in sperm concentration, motility, and semen volume, the differences are small. There is no difference in pregnancy rates between patients receiving selenium, carnitine, and coenzyme Q10, or placebo. The quality of studies is poor, limiting the level of evidence.