The Effect of L-Carnitine on Cadmium Toxicity in Liver and Kidney Tissue in Prepubertal Female Rats / Efecto de la L-Carnitina sobre la Toxicidad del Cadmio en el Hígado y el Tejido Renal en Ratas Hembras Prepúberes

SUMMARY: Cadmium (Cd) is a toxic element that accumulates in kidney and liver. L-carnitine(LC) is a natural compound that has been shown to exhibit antioxidant activity. Aim of this study was to investigate the effect of L-carnitine against cadmium-induced changes in liver and kidney tissues in prepubertal female rats. In this study 21-day-old female Wistar Albino rats were used. Control, cadmium (2 mg/kg cadmium intraperitoneally), L-carnitine (300 mg/kg orally) and cadmium+L-carnitine groups were formed. Liver and kidney tissue sections were stained with Hematoxylin-Eosin and Masson Trichrome. Histological scoring was performed in liver and kidney. In the liver tissue given Cd, bile duct proliferation, inflammation cells and connective tissue in the portal area were decreased in treatment group. In kidneys, cadmium group treated with L-carnitine, it was observed that the capillary congestion in the kidneys decreased, but tubular dilatation continued in some places. In fibrosis scoring of the liver groups,statistically significant decrease was observed in the Cd+LC group compared to group of cadmium. In the histological scoring results of the kidney groups, statistically significant decrease in congestion and tubular epithelial degeneration was observed in the group treated with L-carnitine compared to group with cadmium. In conclusion medium-dose cadmium has toxic effects in liver and kidney of prepubertal female rats in subacute period,these effects are alleviated with L-carnitine.

El cadmio (Cd) es un elemento tóxico que se acumula en los riñones y el hígado. La L-carnitina (LC) es un compuesto natural que ha demostrado tener actividad antioxidante. El objetivo de este estudio fue investigar el efecto de la L-carnitina contra los cambios inducidos por el cadmio en los tejidos del hígado y el riñón en ratas hembra prepúberes. En este estudio se utilizaron ratas Wistar Albinas hembra de 21 días de edad. Se formaron grupos control, cadmio (2 mg/kg de cadmio por vía intraperitoneal), L- carnitina (300 mg/kg por vía oral) y cadmio + L-carnitina. Se tiñeron secciones de tejido de hígado y riñón con Hematoxilina-Eosina y tricrómico de Masson. La puntuación histológica se realizó en hígado y riñón. En el tejido hepático que recibió Cd, la proliferación de los conductos biliares, las células inflamatorias y el tejido conectivo en el área portal disminuyeron en el grupo con tratamiento. En los riñones, en el grupo de cadmio tratado con L- carnitina, se observó que la congestión capilar disminuyó, pero la dilatación tubular continuó en algunos sitios. En la puntuación de fibrosis de los grupos de hígado, se observó una disminución estadísticamente significativa en el grupo de Cd+LC en comparación con el grupo de cadmio. Los resultados de puntuación histológica de los grupos de riñón, arrojó una disminución estadísticamente significativa en la congestión y el epitelio tubular Se observó degeneración en el grupo tratado con L-carnitina en comparación con el grupo con cadmio. En conclusión, las dosis medias de cadmio tienen efectos tóxicos en el hígado y los riñones de ratas hembras prepúberes en el período subagudo; estos efectos se alivian con L-carnitina.

Exploring the potential anti-thyroid activity of Acetyl-L-carnitine: Lactoperoxidase inhibition profile, iodine complexation and scavenging power against H2O2. Experimental and theoretical studies.

L-Acetylcarnitine (ALC), a versatile compound, has demonstrated beneficial effects in depression, Alzheimer's disease, cognitive impairment, and other conditions. This study focuses on its antithyroid activity. The precursor molecule, L-carnitine, inhibited the uptake of triiodothyronine (T3) and thyroxine (T4), and it is possible that ALC may reduce the iodination process of T3 and T4. Currently, antithyroid drugs are used to control the excessive production of thyroid hormones (TH) through various mechanisms: (i) forming electron donor-acceptor complexes with molecular iodine, (ii) eliminating hydrogen peroxide, and (iii) inhibiting the enzyme thyroid peroxidase. To understand the pharmacological properties of ALC, we investigated its plausible mechanisms of action. ALC demonstrated the ability to capture iodine (Kc = 8.07 ± 0.32 x 105 M-1), inhibit the enzyme lactoperoxidase (LPO) (IC50 = 17.60 ± 0.76 µM), and scavenge H2O2 (39.82 ± 0.67 mM). A comprehensive physicochemical characterization of ALC was performed using FTIR, Raman, and UV-Vis spectroscopy, along with theoretical DFT calculations. The inhibition process was assessed through fluorescence spectroscopy and vibrational analysis. Docking and molecular dynamics simulations were carried out to predict the binding mode of ALC to LPO and to gain a better understanding into the inhibition process. Furthermore, albumin binding experiments were also conducted. These findings highlight the potential of ALC as a therapeutic agent, providing valuable insights for further investigating its role in the treatment of thyroid disorders.

l-carnitine enhances the kinematics and protects the sperm membranes of chilled and frozen-thawed Peruvian Paso horse spermatozoa.

l-carnitine (LC) transports fatty acids to the mitochondria for energy production, reducing lipid availability for peroxidation through ß-oxidation. This research examines the effect of LC supplementation to two skimmed milk-based extenders on the cryosurvival of chilled (5°C) and frozen-thawed Peruvian Paso horse spermatozoa .An initial experiment determined the optimal LC concentration (0, 1, 5, 10, 25, and 50 mM) when added to INRA-96® and UHT (skimmed milk + 6% egg yolk) extenders, using nine ejaculates from three stallions chilled for up to 96 h. Subsequently, the effect of 25 mM LC supplementation (the optimal concentration) on chilling (INRA-96) and freezing (INRA-Freeze®) extenders was evaluated using eight pooled samples from sixteen ejaculates (2 ejaculates/pool) from four stallions. Results indicated that all LC concentrations produced significantly higher values (P<0.05) for kinematic variables (total [TM] and progressive motilities, curvilinear [VCL] and straight-line [VSL] velocity, and beat-cross frequency [BCF]), and the integrity of plasma/acrosome membranes (IPIA) compared to non-supplemented chilled sperm samples for up to 96 h with both extenders. Moreover, the use of 25 mM LC was more efficient (P<0.05) in preserving the post-chilled values of velocity, BCF, and IPIA for the long term than lower LC concentrations (1-10 mM). Post-thaw values of total motility, the amplitude of lateral head displacement (ALH), and IPIA were significantly improved (P<0.05) when INRA-Freeze extender was supplemented with 25 mM LC. In conclusion, supplementation of l-carnitine to skimmed milk-based extenders enhanced kinematic variables and protected the membrane integrity in chilled and frozen-thawed Peruvian Paso horse spermatozoa.

L-2 hydroxyglutaric aciduria: report of a Mexican-Mayan patient with the mutation c.569C>T and response to vitamin supplements and levocarnitine.

Background: L-2-hydroxyglutaric aciduria (L2HGA) is a rare inherited autosomal recessive neurometabolic disorder caused by pathogenic variants in the L2HGDH gene which encodes mitochondrial 2-hydroxyglutarate dehydrogenase. Here, we report a case of L2HGA in a Mexican-Mayan patient with a homozygous mutation at L2HGDH gene and clinical response to vitamin supplements and levocarnitine. Case report: A 17-year-old, right-handed female patient with long-term history of seizures, developmental delay and ataxia was referred to a movement disorders specialist for the evaluation of tremor. Her brain MRI showed typical findings of L2HGA. The diagnosis was corroborated with elevated levels of 2-hydroxyglutaric acid in urine and genetic test which revealed a homozygous genetic known variant c.569C>T in exon 5 of L2HGDH gene. She was treated with levocarnitine and vitamin supplements, showing improvement in tremor and gait. Discussion: To our knowledge this is the first report of a Mexican patient with L2HGA. This case adds information about a rare condition in a different ethnic group and supports the findings of other authors which encountered symptomatic improvement with the use of flavin adenine dinucleotide (and its precursor riboflavin), and levocarnitine. Highlights: We report the first case of Mexican-Mayan patient with L2HGA showing a missense homozygous mutation in L2HGDH gene, and improvement of symptoms with vitamin supplements and levocarnitine.

Effects of N-acetylcysteine and acetyl-L-carnitine on acute PTZ-induced seizures in larval and adult zebrafish.

BACKGROUND: Epilepsy is a prevalent neurological disease, affecting approximately 1-2% of the global population. The hallmark of epilepsy is the occurrence of epileptic seizures, which are characterized by predictable behavioral changes reflecting the underlying neural mechanisms of the disease. Unfortunately, around 30% of patients do not respond to current pharmacological treatments. Consequently, exploring alternative therapeutic options for managing this condition is crucial. Two potential candidates for attenuating seizures are N-acetylcysteine (NAC) and Acetyl-L-carnitine (ALC), as they have shown promising neuroprotective effects through the modulation of glutamatergic neurotransmission. METHODS: This study aimed to assess the effects of varying concentrations (0.1, 1.0, and 10 mg/L) of NAC and ALC on acute PTZ-induced seizures in zebrafish in both adult and larval stages. The evaluation of behavioral parameters such as seizure intensity and latency to the crisis can provide insights into the efficacy of these substances. RESULTS: Our results indicate that both drugs at any of the tested concentrations were not able to reduce PTZ-induced epileptic seizures. On the other hand, the administration of diazepam demonstrated a notable reduction in seizure intensity and increased latencies to higher scores of epileptic seizures. CONCLUSION: Consequently, we conclude that, under the conditions employed in this study, NAC and ALC do not exhibit any significant effects on acute seizures in zebrafish.

Omega-3 fatty acids and L-carnitine prevent meiotic oocyte damage induced by follicular fluid from infertile women with endometriosis: an experimental study.

OBJECTIVE: To assess whether follicular fluid (FF) from infertile women with endometriosis in advanced stages [moderate/severe (EIII/IV) without or with endometrioma (Endometrioma)] induce more oocyte damages than in early stages (minimal/mild: EI/II); and whether supplementation with L-carnitine (LC) and omega 3 (n3) can prevent these oocyte damages. METHODS: Experimental study using bovine oocytes (obtained of ovaries from slaughterhouse), and human FF (samples were obtained during oocyte recovery for ICSI). Bovine oocytes were submitted to in vitro maturation (IVM) divided into 9 groups: no FF(No-FF), with 1% FF from infertile women without endometriosis (FFC), with EI/II, EIII/IV and Endometrioma, and with (or not) LC+n3 addition. After IVM, oocytes were fluorescently labelled and visualized by confocal microscopy to analyze chromosomes and spindle. RESULTS: FF from endometriosis decreased rate of normal MII (spindle assembly and chromosome alignment) compared to No-FF (87.2%) and FFC (87.2%). FFEIII/IV (80.7%) and FFEndometrioma (69.3%) decreased total MII rate compared to No-FF (91.9%) and FFC (89.2%), and FFEndometrioma had lower total MII rate compared to other groups. LC+n3 increased MII rate in the FFEIII/IV (80.7% vs. 90.8%) and the Endometrioma (69.3% vs. 86.4%), and it prevented damages in spindle and chromosomes in MII oocytes in the FFEI/II group (62.2% vs. 84.5%) and the FFEIII/IV group (70.2% vs. 84.1%). CONCLUSIONS: FF of endometriosis damaged the meiotic spindle of bovine MII oocytes. EIII/IV led to impaired nuclear maturation; FF from women with endometrioma had further negative impact in oocyte maturation. LC+n3 completely prevented the effects of FF from women with endometriosis on oocyte.

A randomized clinical trial to evaluate the efficacy of L-carnitine L-tartrate to modulate the effects of SARS-CoV-2 infection.

Introduction: L-carnitine (LC) has been associated with inflammatory mediator reduction and with downregulating the angiotensin-converting enzyme-2 (ACE2) receptor, which is the target of SARS-CoV-2 attachment. Methods: This pilot phase 2 randomized, double-blind placebo-controlled trial contained two cohorts. Cohort 1 comprised 101 individuals with negative RT-PCR SARS-CoV-2 test results who cohabitated with an individual diagnosed with SARS-CoV-2 infection. Cohort 2 comprised 122 individuals with positive SARS-CoV-2 RT-PCR test results who were asymptomatic or had mild COVID-19 pneumonia symptoms. Participants in each cohort were randomized 1:1 to receive either 2 g elemental oral LC supplementation or placebo daily for 21 days. Primary endpoints included adverse events, SARS-CoV-2 infection incidence in Cohort 1, and disease progressions in Cohort 2. Secondary endpoints included between-group laboratory profile comparisons and Cohort 2 ACE1/ACE2 plasma levels. Disease progression was compared between the Cohort 2 groups using chest computed tomography. Results: In Cohort 1, two SARS-CoV-2 infections occurred in each group. The common adverse events included headache, dyspnea, and tiredness. In Cohort 2, platelet counts were elevated, and fibrinogen levels reduced in the LC group compared with those of the placebo group. Conclusion: Our study showed that LC was well-tolerated and suggests it modulates coagulation pathways. Furthermore, chest computed tomography images of the Cohort 2 LC group showed significant lung lesion improvement, suggesting that LC may slow COVID-19 progression.

Increased cytokine levels induced by high phenylalanine concentrations in late diagnosis PKU patients compared to early diagnosis: Anti-inflammatory effect of L-carnitine.

Phenylketonuria (PKU) was the first genetic disease to have an effective therapy, which consists of phenylalanine intake restriction. However, there are patients who do not adhere to treatment and/or are not submitted to neonatal screening. PKU patients present L-carnitine (L-car) deficiency, compound that has demonstrated an antioxidant and anti-inflammatory role in metabolic diseases. This study evaluated the effect caused by exposure time to high Phe levels in PKU patients at early and late diagnosis, through pro- and anti-inflammatory cytokines, as well as the L-car effect in patients under treatment. It was observed that there was a decrease in phenylalanine levels in treated patients compared to patients at diagnosis, and an increase in L-car levels in the patients under treatment. Inverse correlation between Phe versus L-car and nitrate plus nitrite versus L-car in PKU patients was also showed. We found increased proinflammatory cytokines levels: interleukin (IL)-1ß, interferons (IFN)-gamma, IL-2, tumor necrosis factor (TNF)-alpha, IL-8 and IL-6 in the patients at late diagnosis compared to controls, and IL-8 in the patients at early diagnosis and treatment compared to controls. Increased IL-2, TNF-alpha, IL-6 levels in the patients at late diagnosis compared to early diagnosis were shown, and reduced IL-6 levels in the treated patients compared to patients at late diagnosis. Moreover, it verified a negative correlation between IFN-gamma and L-car in treated patients. Otherwise, it was observed that there were increased IL-4 levels in the patients at late diagnosis compared to early diagnosis, and reduction in treated patients compared to late diagnosed patients. In urine, there was an increase in 8-isoprostane levels in the patients at diagnosis compared to controls and a decrease in oxidized guanine species in the treated patients compared to the diagnosed patients. Our results demonstrate for the first time in literature that time exposure to high Phe concentrations generates a proinflammatory status, especially in PKU patients with late diagnosis. A pro-oxidant status was verified in not treated PKU patients. Our results demonstrate the importance of early diagnosis and prompt start of treatment, in addition to the importance of L-car supplementation, which can improve cellular defense against inflammation and oxidative damage in PKU patients.

Does L-carnitine prevent cadmium-induced damage in gastrointestinal contractility and histological changes in prepubertal rat / ¿La L-carnitina previene el daño inducido por cadmio en la contractilidad gastrointestinal y los cambios histológicos en ratas prepúberes?

SUMMARY: Cadmium (Cd) is the industrial and environmental toxic heavy metal which is found in air, water and soil. Cd, adversely affects many organs in humans such as kidney, intestine, liver, testis and lungs. L-carnitine (LC) is an important agent that plays essential role in energy metabolism. In our study, we aimed to work out whether LC application has any protective effect on intestinal contractility and morphologic damage of prepubertal rat duodenum on Cd-induced toxicity. Twenty eight prepubertal female Wistar rats were divided into four groups. The first group is control (C), second group; Cd group; Cadmium chloride was given 2 mg/kg 28 days with a one-day break by i.p. The third group; Cd+LC, which cadmium chloride was given 2 mg/kg i.p. and LC was given orally by gastric lavage. The LC dose was given as 75 mg/kg. The fourth group; LC, which only LC was given orally. The intestinal segments were isolated and suspended in tissue bath. Contractile responses were induced by acetylcholine (ACh) and relaxation was achieved with phenylephrine. Also the segments were examined for histological changes by light microscopy. Ach-induced contractions were higher in Cd+LC, LC, and control group compared to the Cd group in duodenal segments. The phenylephrine-induced relaxations were lower in Cd groups as compared with Control, Cd+LC and LC group in duodenal segments. In Cd group intestinal morphology was observed to be severely damaged whereas in Cd+LC group the damage was noticeably lower. Cd administration caused severe cellular damage and decreased gastrointestinal motility. Treatment with the LC has affected the gastrointestinal contractility and reduced the damage in intestinal morphology, which occured after Cd application.

El cadmio (Cd) es el metal pesado tóxico industrial y ambiental que se encuentra en el aire, el agua y el suelo. El Cd afecta negativamente a muchos órganos humanos, como los riñones, los intestinos, el hígado, los testículos y los pulmones. La L-carnitina (LC) es un agente importante que juega un rol esencial en el metabolismo energético. El objetivo de este estudio fue determinar si la aplicación de LC tiene algún efecto protector sobre la contractilidad intestinal y el daño morfológico del duodeno de rata prepuberal sobre la toxicidad inducida por Cd. Veintiocho ratas Wistar hembras prepúberes se dividieron en cuatro grupos. El primer grupo control (C), segundo grupo; grupo cd; Se administró cloruro de cadmio 2 mg/kg durante 28 días con un descanso de un día por vía i.p. El tercer grupo; Cd+LC, al que se administró cloruro de cadmio 2 mg/kg i.p. y LC se administró por vía oral mediante lavado gástrico. La dosis de LC se administró como 75 mg/kg. El cuarto grupo; LC, al cual solo LC se administraba por vía oral. Los segmentos intestinales fueron aislados y suspendieron en baño de tejido. Las respuestas contráctiles fueron inducidas por acetilcolina (ACh) y la relajación se logró con fenilefrina. También se examinaron los segmentos en busca de cambios histológicos mediante microscopía óptica. Las contracciones inducidas por Ach fueron mayores en Cd+LC, LC y el grupo control en comparación con el grupo Cd en los segmentos duodenales. Las relajaciones inducidas por fenilefrina fueron menores en los grupos Cd en comparación con el grupo Control, Cd+LC y LC en los segmentos duodenales. En el grupo Cd se observó que la morfología intestinal estaba severamente dañada mientras que en el grupo Cd+LC el daño fue notablemente menor. La administración de Cd causó daño celular severo y disminución de la motilidad gastrointestinal. El tratamiento con LC afectó la contractilidad gastrointestinal y redujo el daño en la morfología intestinal, que ocurría después de la aplicación de Cd.

Quantitative systems pharmacology Model to characterize valproic acid-induced hyperammonemia and the effect of L-carnitine supplementation.

Valproic acid (VPA) is a short-chain fatty acid widely prescribed in the treatment of seizure disorders and epilepsy syndromes, although its therapeutic value may be undermined by its toxicity. VPA serious adverse effects are reported to have a significant and dose-dependent incidence, many associated with VPA-induced hyperammonemia. This effect has been linked with reduced levels of carnitine; an endogenous compound involved in fatty acid's mitochondrial ß-oxidation by facilitation of its entrance via the carnitine shuttle. High exposure to VPA can lead to carnitine depletion causing a misbalance between the intra-mitochondrial ß-oxidation and the microsomal ω-oxidation, a pathway that produces toxic metabolites such as 4-en-VPA which inhibits ammonia elimination. Moreover, a reduction in carnitine levels might be also related to VPA-induced obesity and lipids disorder. In turn, L-carnitine supplementation (CS) has been recommended and empirically used to reduce VPA's hepatotoxicity. The aim of this work was to develop a Quantitative Systems Pharmacology (QSP) model to characterize VPA-induced hyperammonemia and evaluate the benefits of CS in preventing hyperammonemia under both chronic treatment and after VPA overdosing. The QSP model included a VPA population pharmacokinetics model that allowed the prediction of total and unbound concentrations after single and multiple oral doses considering its saturable binding to plasma proteins. Predictions of time courses for 2-en-VPA, 4-en-DPA, VPA-glucuronide, carnitine, ammonia and urea levels, and for the relative change in fatty acids, Acetyl-CoA, and glutamate reflected the VPA induced changes and the efficacy of the treatment with L-carnitine. The QSP model was implemented to give a rational basis for the L-carnitine dose selection to optimize CS depending on VPA dosage regime and to assess the currently recommended L-carnitine rescue therapy after VPA overdosing. Results show that a L-carnitine dose equal to the double of the VPA dose using the same interdose interval would maintain the ammonia levels at baseline. The QSP model may be expanded in the future to describe other adverse events linked to VPA-induced changes in endogenous compounds.

Effect of ß - hydroxy - γ -aminophosphonate (ß - HPC) on the hydrolytic activity of Nocardia brasiliensis as determined by FT-IR spectrometry.

The use of immunomodulatory and metabolic modulating drugs has been considered a better strategy to improve the efficacy of conventional treatments against pathogens and metabolic diseases. L-carnitine is relevant in fatty acid metabolism and energy production by ß-oxidation, but it also has a beneficial therapeutic immunomodulatory effect. The ß-hydroxy-γ-aminophosphonate (ß-HPC) was developed, synthesized and studied in different pathologies as a more soluble and stable analog than L-carnitine, which has been studied in bacterial physiology and metabolism; therefore, we set out to investigate the direct effect of ß-HPC on the metabolism of N. brasiliensis, which causes actinomycetoma in Mexico and is underdiagnosed. To analyze the effect of ß-HPC on the metabolic capacity of the bacterium for the hydrolysis of substrate casein, L-tyrosine, egg yolk, and tween 80, Fourier transform infrared spectroscopy (FT-IR) was employed. It was found that ß-HPC increases the metabolic activity of N. brasiliensis associated with increased growth and increased hydrolysis of the substrates tested. By the effect of ß-HPC, it was observed that, in the hydrolysis of L-tyrosine, the aromatic ring and functional groups were degraded. At 1515 cm-1, any distinctive signal or peak for this amino acid was missing, almost disappearing at 839, 720, 647, and 550 cm-1. In casein, hydrolysis is enhanced in the substrate, which is evident by the presence of NH, OH, amide, and CO. In casein, hydrolysis is enhanced in the substrate, which is evident by the presence of NH, OH, amide, COO, and P = O signals, characteristic of amino acids, in addition to the increase of the amide I and II bands. In Tween 80 the H-C = and C = C signals disappear and the ether signals are concentrated, it was distinguished by the intense band at 1100 cm-1. Egg yolk showed a large accumulation of phosphate groups at 1071 cm-1, where phosvitin is located. FT-IR has served to demonstrate that ß-HPC is a hydrolysis enhancer. Furthermore, by obtaining the spectrum of N. brasiliensis, we intend to use it as a quick comparison tool with other spectra related to actinobacteria. Eventually, FT-IR may serve as a species identification option.

The role of L-carnitine in bovine embryo metabolism. A review of the effect of supplementation with a metabolic modulator on in vitro embryo production.

Early embryo development is driven first by the maternal RNAs and proteins accumulated during the oocyte's cytoplasmic maturation and then after the embryo genome activation. In mammalian cells, ATP generation occurs via oxidative pathways or by glycolysis, whereas in embryonic stem cells, the consumption of glucose, pyruvate, lipids, and amino acids results in ATP synthesis. Although the bovine embryo has energy reserves in glycogen and lipids, the glycogen concentration is deficient. Conversely, lipids represent the most abundant energy reservoir of bovine embryos, where lipid droplets-containing triacylglycerols are the main fatty acid stores. Oocytes of many mammalian species contain comparatively high amounts of lipids stored as droplets in the ooplasm. L-carnitine has been described as a cofactor that facilitates the mobilization of fatty acids present in the oocyte's cytoplasm into the mitochondria to facilitate ß-oxidation processes. However, the L-carnitine effects by addition to media in the in vitro produced embryos on the quality are highly disputed and contradictory by different researchers. This review's objective was to explore the effect that the addition of L-carnitine on culture media could have on the overall bovine embryo production in vitro, from the oocyte metabolism to the modulation of gene expression in the developing embryos.

L-carnitine reduces acute lung injury via mitochondria modulation and inflammation control in pulmonary macrophages

Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a critical respiratory syndrome with limited effective interventions. Lung macrophages play a critical role in the pathogenesis of abnormal inflammatory response in the syndrome. Recently, impaired fatty acid oxidation (FAO), one of the key lipid metabolic signalings, was found to participate in the onset and development of various lung diseases, including ALI/ARDS. Lipid/fatty acid contents within mouse lungs were quantified using the Oil Red O staining. The protective effect of FAO activator L-carnitine (Lca, 50, 500, or 5 mg/mL) was evaluated by cell counting kit 8 (CCK-8) assay, real-time quantitative PCR (qPCR), ELISA, immunoblotting, fluorescence imaging, and fluorescence plate reader detection in lipopolysaccharide (LPS) (100 ng/mL)-stimulated THP-1-derived macrophages. The in vivo efficacy of Lca (300 mg/kg) was determined in a 10 mg/kg LPS-induced ALI mouse model. We found for the first time that lipid accumulation in pulmonary macrophages was significantly increased in a classical ALI murine model, which indicated disrupted FAO induced by LPS. Lca showed potent anti-inflammatory and antioxidative effects on THP-1 derived macrophages upon LPS stimulation. Mechanistically, Lca was able to maintain FAO, mitochondrial activity, and ameliorate mitochondrial dynamics. In the LPS-induced ALI mouse model, we further discovered that Lca inhibited neutrophilic inflammation and decreased diffuse damage, which might be due to the preservation of mitochondrial homeostasis. These results broadened our understanding of ALI/ARDS pathogenesis and provided a promising drug candidate for this syndrome.

The supplementation of L-carnitine in septic shock patients: Systematic review and meta-analysis.

BACKGROUND: Sepsis and septic shock are severe and difficult-to-treat conditions with high lethality. There is interest in identifying new adjunct therapies that are effective in reducing mortality. In this context, L-carnitine has been investigated in trials as a potentially beneficial drug. Therefore, the aim of this systematic review was to assess the clinical evidence to support the use of L-carnitine in septic shock patients to reduce the risk of mortality. The objective of this review was to evaluate the effect of L-carnitine compared to placebo or Usual Care (UC) on the mortality rate in hospitalized adult septic shock patients. METHODS: The authors exclusively included randomized clinical trials that compared the use of L-carnitine versus placebo in adult (> 18 years old) septic shock patients. The outcome was a mortality rate of 28 days. This systematic review and meta-analysis were performed following the PRISMA guidelines and registered in PROSPERO with the ID CRD42020180499. RESULTS: Following the initial search, 4007 citations were identified, with 2701 remaining after duplicate removal. Eight citations were selected for body text reading, and two were selected for inclusion. The studies enrolled 275 patients, with 186 in the carnitine arm and 89 in the placebo arm. The effect of L-carnitine uses in septic shock patients showed a difference risk of -0.03 (95% Confidence Interval: -0.15-0.10, I2 = 77%, p = 0.69) compared to placebo/in mortality rate with low quality of evidence. CONCLUSIONS: There is low-quality evidence that the use of L-carnitine has no significant effect on reducing 28-day mortality in septic shock patients.

The role of efflux transporters and metabolizing enzymes in brain and peripheral organs to explain drug-resistant epilepsy.

Drug-resistant epilepsy has been explained by different mechanisms. The most accepted one involves overexpression of multidrug transporters proteins at the blood brain barrier and brain metabolizing enzymes. This hypothesis is one of the main pharmacokinetic reasons that lead to the lack of response of some antiseizure drug substrates of these transporters and enzymes due to their limited entrance into the brain and limited stay at the sites of actions. Although uncontrolled seizures can be the cause of the overexpression, some antiseizure medications themselves can cause such overexpression leading to treatment failure and thus refractoriness. However, it has to be taken into account that the inductive effect of some drugs such as carbamazepine or phenytoin not only impacts on the brain but also on the rest of the body with different intensity, influencing the amount of drug available for the central nervous system. Such induction is not only local drug concentration but also time dependent. In the case of valproic acid, the deficient disposition of ammonia due to a malfunction of the urea cycle, which would have its origin in an intrinsic deficiency of L-carnitine levels in the patient or by its depletion caused by the action of this antiseizure drug, could lead to drug-resistant epilepsy. Many efforts have been made to change this situation. In order to name some, the administration of once-daily dosing of phenytoin or the coadministration of carnitine with valproic acid would be preferable to avoid iatrogenic refractoriness. Another could be the use of an adjuvant drug that down-regulates the expression of transporters. In this case, the use of cannabidiol with antiseizure properties itself and able to diminish the overexpression of these transporters in the brain could be a novel therapy in order to allow penetration of other antiseizure medications into the brain.

The supplementation of L-carnitine in septic shock patients: Systematic review and meta-analysis

Abstract Background Sepsis and septic shock are severe and difficult-to-treat conditions with high lethality. There is interest in identifying new adjunct therapies that are effective in reducing mortality. In this context, L-carnitine has been investigated in trials as a potentially beneficial drug. Therefore, the aim of this systematic review was to assess the clinical evidence to support the use of L-carnitine in septic shock patients to reduce the risk of mortality. The objective of this review was to evaluate the effect of L-carnitine compared to placebo or Usual Care (UC) on the mortality rate in hospitalized adult septic shock patients. Methods The authors exclusively included randomized clinical trials that compared the use of L-carnitine versus placebo in adult (> 18 years old) septic shock patients. The outcome was a mortality rate of 28 days. This systematic review and meta-analysis were performed following the PRISMA guidelines and registered in PROSPERO with the ID CRD42020180499. Results Following the initial search, 4007 citations were identified, with 2701 remaining after duplicate removal. Eight citations were selected for body text reading, and two were selected for inclusion. The studies enrolled 275 patients, with 186 in the carnitine arm and 89 in the placebo arm. The effect of L-carnitine uses in septic shock patients showed a difference risk of -0.03 (95% Confidence Interval: -0.15-0.10, I2 = 77%, p = 0.69) compared to placebo/in mortality rate with low quality of evidence. Conclusions There is low-quality evidence that the use of L-carnitine has no significant effect on reducing 28-day mortality in septic shock patients.

The effects of L-carnitine on gastrointestinal contractility and histological changes in rat intestinal ischemia-reperfusion Injury / Efectos de la l-carnitina sobre la contractilidad gastrointestinal y los cambios histológicos en la lesión por isquemia-reperfusión intestinal de rata

SUMMARY: Ischemia-reperfusion (I/R) of the small intestine causes serious abdominal pathologies including tissue dysfunction and organ failure. L-carnitine (L-C), a powerful antioxidant, may help lessen the severity of these pathological effects since it plays a key role in energy metabolism. In this work we aimed to study the effects of L-C on the isolated ileal and duodenal contractility and histological changes in intestinal ischemia and reperfusion injury. Twenty eight Wistar rats were divided into four groups. The first group is the control group. Second group, I/R group, had rats submitted to 45-minutes of intestinal ischemia and to 45-minutes reperfusion. The third group, I/R+ L-C group, rats were treated with L-C 5 minutes before reperfusion and than submitted to ischemia. The fourth group, included rats that were treated with L-C without ischemia or reperfusion. Intestinal ischemia was conducted by obstructing superior mesentery arteries by silk loop. The ileal and duodenal segments were isolated and suspended in tissue bath. Contractile responses were induced by acetylcholine (Ach) and relaxation was achieved with phenylephrine. At the same time the terminal ileal and duodenal segments were examined for histological changes. Ach-induced contraction responses were higher in the I/R+L-C group, the L-C group, and the control group compared to the I/R group, in both ileal and duodenal segments. On the other hand, the phenylephrine-induced relaxations were higher in the I/R+L-C and L-C groups, especially in duodenal segments. In I/R group intestinal morphology was observed to be severely damaged whereas in I/R+L-C group the damage was noticeably lower possibly due to protective properties of L-C. I/R injury caused severe cellular damage response within the muscularis resulting in decreased gastrointestinal motility. Treatment with the L-C has significantly affected the gastrointestinal contractility. Also L-C treatment reduced the damage in intestinal morphology that occurs after IR injury.

RESUMEN: La isquemia-reperfusión (I/R) del intestino delgado provoca graves patologías abdominales que incluyen disfunción tisular y falla orgánica. La L-carnitina (L-C), un poderoso antioxidante, puede ayudar a disminuir la gravedad de estos efectos patológicos, ya que desempeña un papel clave en el metabolismo energético. El objetivo de este trabajo fue estudiar los efectos de L-C sobre la contractilidad ileal y duodenal aislada y los cambios histológicos en la lesión por isquemia y reperfusión intestinal. Se dividieron 28 ratas Wistar en cuatro grupos. El primer grupo fue el control. El segundo grupo, grupo I/R, de ratas sometidas durante 45 minutos de isquemia intestinal y a 45 minutos de reperfusión. El tercer grupo, grupo I/R+ L-C, las ratas se trataron con L-C, 5 minutos antes de la reperfusión y luego se sometieron a isquemia. El cuarto grupo, las ratas fueron tratadas con L-C sin isquemia ni reperfusión. La isquemia intestinal se realizó obstruyendo la arteria mesentérica superior con un asa de seda. Los segmentos ileal y duodenal se aislaron y suspendieron en un baño de tejido. Las respuestas contráctiles fueron inducidas por acetilcolina (Ach) y la relajación se logró con fenilefrina. Al mismo tiempo, se examinaron cambios histológicos de los segmentos del íleon terminal y del duodeno. Las respuestas de contracción inducidas por Ach fueron mayores en el grupo I/R+L-C, el grupo L-C y el grupo control en comparación con el grupo I/R, tanto en el segmento ileal como en el duodenal. Por otra parte, las relajaciones inducidas por fenilefrina fueron mayores en los grupos I/R+L-C y L-C, especialmente en los segmentos duodenales. En el grupo I/R se observó que la morfología intestinal estaba dañada significativamente, mientras que en el grupo I/R+L-C el daño fue notablemente menor, posiblemente debido a las propiedades protectoras de L-C. La lesión por I/R causó una respuesta de daño celular severo dentro de la capa muscular que resultó en una disminución de la motilidad gastrointestinal. El tratamiento con L-C afectó significativamente la contractilidad gastrointestinal. Por otra parte, el tratamiento L-C redujo el daño en la morfología intestinal que ocurre después de la lesión por IR.

Biomedical role of L-carnitine in several organ systems, cellular tissues, and COVID-19 / Papel biomédico da L-carnitina em vários sistemas de órgãos, tecidos celulares e COVID-19

Carnitine is a conditionally necessary vitamin that aids in energy creation and fatty acid metabolism. Its bioavailability is higher in vegetarians than in meat-eaters. Deficits in carnitine transporters occur because of genetic mutations or in conjunction with other illnesses. Carnitine shortage can arise in health issues and diseases­including hypoglycaemia, heart disease, starvation, cirrhosis, and ageing­because of abnormalities in carnitine control. The physiologically active form of L-carnitine supports immunological function in diabetic patients. Carnitine has been demonstrated to be effective in the treatment of Alzheimer's disease, several painful neuropathies, and other conditions. It has been used as a dietary supplement for the treatment of heart disease, and it also aids in the treatment of obesity and reduces blood glucose levels. Therefore, L-carnitine shows the potential to eliminate the influences of fatigue in COVID-19, and its consumption is recommended in future clinical trials to estimate its efficacy and safety. This review focused on carnitine and its effect on tissues, covering the biosynthesis, metabolism, bioavailability, biological actions, and its effects on various body systems and COVID-19.

A carnitina é uma vitamina condicionalmente necessária que auxilia na geração de energia e no metabolismo de ácidos graxos. Sua biodisponibilidade é maior em vegetarianos do que em carnívoros. Déficits nos transportadores de carnitina ocorrem devido a mutações genéticas ou em conjunto com outras doenças. A escassez de carnitina pode surgir em problemas de saúde e doenças ­ incluindo hipoglicemia, doenças cardíacas, fome, cirrose e envelhecimento ­ devido a anormalidades no controle da carnitina. A forma fisiologicamente ativa da L-carnitina suporta a função imunológica em pacientes diabéticos. A carnitina demonstrou ser eficaz no tratamento da doença de Alzheimer, várias neuropatias dolorosas e outras condições. Tem sido utilizado como suplemento dietético para o tratamento de doenças cardíacas, também auxilia no tratamento da obesidade e reduz os níveis de glicose no sangue. Portanto, a L-carnitina mostra potencial para eliminar as influências da fadiga na COVID-19 e seu consumo é recomendado em futuros ensaios clínicos para estimar sua eficácia e segurança. Esta revisão enfocou a carnitina e seu efeito nos tecidos, abrangendo a biossíntese, metabolismo, biodisponibilidade, ações biológicas e seus efeitos em vários sistemas corporais e COVID-19.

L-carnitine protects DNA oxidative damage induced by phenylalanine and its keto acid derivatives in neural cells: a possible pathomechanism and adjuvant therapy for brain injury in phenylketonuria.

Although phenylalanine (Phe) is known to be neurotoxic in phenylketonuria (PKU), its exact pathogenetic mechanisms of brain damage are still poorly known. Furthermore, much less is known about the role of the Phe derivatives phenylacetic (PAA), phenyllactic (PLA) and phenylpyruvic (PPA) acids that also accumulate in this this disorder on PKU neuropathology. Previous in vitro and in vivo studies have shown that Phe elicits oxidative stress in brain of rodents and that this deleterious process also occurs in peripheral tissues of phenylketonuric patients. In the present study, we investigated whether Phe and its derivatives PAA, PLA and PPA separately or in combination could induce reactive oxygen species (ROS) formation and provoke DNA damage in C6 glial cells. We also tested the role of L-carnitine (L-car), which has been recently considered an antioxidant agent and easily cross the blood brain barrier on the alterations of C6 redox status provoked by Phe and its metabolites. We first observed that cell viability was not changed by Phe and its metabolites. Furthermore, Phe, PAA, PLA and PPA, at concentrations found in plasma of PKU patients, provoked marked DNA damage in the glial cells separately and when combined. Of note, these effects were totally prevented (Phe, PAA and PPA) or attenuated (PLA) by L-car pre-treatment. In addition, a potent ROS formation also induced by Phe and PAA, whereas only moderate increases of ROS were caused by PPA and PLA. Pre-treatment with L-car also prevented Phe- and PAA-induced ROS generation, but not that provoked by PLA and PPA. Thus, our data show that Phe and its major metabolites accumulated in PKU provoke extensive DNA damage in glial cells probably by ROS formation and that L-car may potentially represent an adjuvant therapeutic agent in PKU treatment.

Safety indicators of a novel multi supplement based on guarana, selenium, and L-carnitine: Evidence from human and red earthworm immune cells.

Neurodegenerative diseases are associated with chronic inflammatory states. There is evidence to support the design of novel supplements based on guarana (G) (Paullinia cupana), selenium (S), and L-carnitine (C), the use of which, potentially attenuates neuro oxi-inflammatory conditions. Therefore, this study analyzed the cytotoxic and redox effects of GSC on human leucocytes, the inflammatory activation of microglia BV-2 cells, and effect on mortality, oxidative metabolism, and the immune modulation of red earthworms (Eisenia fetida). The GSC concentrations tested in cell culture were in the range of 0.04-2.1 mg/mL. All the GSC-supplemented samples tested, reverted H2O2 oxidation in DNA molecules, suggesting its genoprotective potential. GSC did not induce mortality in leucocyte cultures. On the contrary, a reduction in the levels of oxidation of lipids, proteins, and cell apoptosis was observed, via downregulation of caspase 3 and 8 genes. GSC showed a dual effect on microglia, decreasing the cellular proliferation at lower concentrations (<0.24 mg/mL) and increasing the cellular proliferation mainly at concentrations > 1.0 mg/mL. GSC did not have a toxic effect on red earthworms, but induced an increase in amoebocyte cells and in brown body formation, indicating immune response activation. The results suggest that GSC could be safe for human consumption.