Valproic Acid Concentrations Research Articles

Association of Valproic Acid and Its Main Metabolites' Plasma Concentrations with Clinical Outcomes among Epilepsy Patients: A 10-Year Retrospective Study Based on Therapeutic Drug Monitoring.

Valproic acid (VPA) is a first-line antiepileptic drug with broad efficacy. Due to significant individual differences in its metabolism, therapeutic drug monitoring is commonly used. However, the recommended therapeutic range (50-100 μg/mL) is inadequate for predicting clinical outcomes. Additionally, the relationship between VPA metabolites and clinical outcomes remains unclear. In this retrospective study, 485 Chinese Southern Han epilepsy patients receiving VPA monotherapy were analyzed after reaching steady-state levels. Plasma concentrations of VPA and its five main metabolites were determined by liquid chromatography-mass spectrometry (LC-MS). We assessed the relevance of the recommended therapeutic VPA range for clinical outcomes and explored the association between VPA/metabolites levels and treatment efficacy/adverse effects. Vitro experiments were conducted to assess 4-ene-VPA hepatotoxicity. The therapeutic range of VPA exhibited no significant correlation with clinical outcomes, and plasma concentrations of VPA failed to serve as predictive indicators for treatment response/adverse effects. Treatment responders had higher 2-PGA concentrations (median, 26.39 ng/mL versus 13.68 ng/mL), with a threshold of 36.5 ng/mL for optimal epilepsy treatment. Patients with abnormal liver function had a higher 4-ene-VPA median concentration (6.41 μg/mL versus 4.83 μg/mL), and the ratio of 4-ene-VPA to VPA better predicted VPA-induced hepatotoxicity (area under the curve, 0.718) than 4-ene-VPA concentration. Vitro experiments revealed that 4-ene-VPA was more hepatotoxic than VPA in HepaRG and L02 cell lines. Total plasma VPA concentration does not serve as a predictor of clinical outcomes. 2-PGA concentrations may be associated with efficacy, whereas the ratio of 4-ene-VPA to VPA may be considered a better biomarker (threshold 10.03%) for VPA-induced hepatotoxicity. SIGNIFICANCE STATEMENT: This was the first and largest observational cohort in China to explore the relationship between patients' parent and metabolites concentrations of VPA and clinical outcomes during the maintenance of VPA monotherapy in epileptic patients. This study provided feasible references of VPA for epilepsy clinical treatment with a larger sample of patients compared with previous studies for a more definitive conclusion based on real-world situations. We found two potential biomarkers in predicting efficacy and liver injury, respectively. This breakthrough has the potential to assist in the rational use of VPA.

A prospective study of drug-drug interaction between antiepileptic drugs and meropenem in patients in a tertiary hospital in China from January 2020 to March 2023.

This study aimed to determine the minimum interaction between different antiepileptic drugs (AEDs) and meropenem (MEPM) for clinical treatment. The data of 91 patients enrolled in the neurology department from January 2020 to March 2023 for clinical trials were measured and observed. Self-controlled studies were conducted to monitor the trough concentrations of valproic acid (VPA), carbamazepine (CBZ) and levotiracetam (LEV) before and after MEPM usage. Relevant indicators of liver and kidney function were also monitored. The serum VPA trough concentrations were 36.25±8.22 μg/ml at 24±12 h and 34.99±11.17 μg/ml at 96±12 h after MEPM use; the difference was significant (p<0.05). Decreased CBZ trough concentrations were also identified after MEPM usage (96±12 h), whereas LEV trough concentrations were not affected. An increased liver injury rate (χ2 =8.744, p<0.05) and a decreased kidney injury rate (χ2 =5.393, p<0.05) were found in the VPA group only. The interaction between VPA and MEPM decreased serum VPA concentrations, increased liver injury rates, and decreased kidney injury rates. In addition, the co-administration of MEPM and CBZ reduced serum CBZ concentrations. Clinicians should be aware of this potential interaction and closely monitor the relevant biochemical indices and number of seizures.

Valproic acid monitoring: Serum prediction using a machine learning framework from multicenter real-world data

BackgroundOur study employs machine learning to predict serum valproic acid (VPA) concentrations, aiming to contribute to the development of non-invasive assays for therapeutic drug monitoring. MethodsMedical records from 2002 to 2019 were obtained from the Taiwan Chang Gung Research Database. Using various machine learning algorithms, we developed predictive models to classify serum VPA concentrations into two categories (1–50 μg/ml or 51–100 μg/ml) and predicted the exact concentration value. The models were trained on 5142 samples and tested on 644 independent samples. Accuracy was the main metric used to evaluate model performance, with a tolerance of 20 μg/ml for continuous variables. Furthermore, we identified important features and developed simplified models with fewer features. ResultsThe models achieved an average accuracy of 0.80–0.86 for binary outcomes and 0.72–0.88 for continuous outcome. Ten top features associated with higher serum VPA levels included higher VPA last and daily doses, bipolar disorder or schizophrenia spectrum disorder diagnoses, elevated levels of serum albumin, calcium, and creatinine, low platelet count, low percentage of segmented white blood cells, and low red cell distribution width-coefficient of variation. The simplified models had an average accuracy of 0.82–0.86 for binary outcome and 0.70–0.86 for continuous outcome. LimitationsThe study's predictive model lacked external test data from outside the hospital for validation. ConclusionsMachine learning models have the potential to integrate real-world data and predict VPA concentrations, providing a promising tool for reducing the need for frequent monitoring of serum levels in clinical practice.

DETERMINATION OF THE LEVEL OF VALPROIC ACID IN THE BLOOD AGAINST THE BACKGROUND OF THE COMBINED USE OF VALPROATES WITH ERTAPENEM IN PEDIATRIC PRACTICE

The article presents a clinical case of the combined use of valproic acid and an antibacterial drug from the carbapenem group – ertapenem in a 15-year-old girl with epilepsy in a pediatric hospital. Therapeutic drug monitoring with an assessment of the level of valproic acid in blood plasma against the background of joint use with carbapenem (ertapenem) allowed to revise and adjust the prescribed antibacterial therapy, and later allowed to adjust the daily dose of sodium valproate in a child with epilepsy. The change of the antibacterial drug was accompanied by an increase in the level of valpro-ic acid in the blood plasma. The transition from intravenous administration of valproic acid to enteral administration of the drug was accompanied by a decrease in the concentration of valproic acid in blood plasma. The authors of the article presented data confirming the need for therapeutic drug moni-toring in children receiving valproic acid and beta-lactam antibiotic from the carbapenem group - ertapenem, based on the known mechanisms of famacokinetic interaction, as well as in patients whose management tactics are planned to change the dosage form of valproic acid.

Cholesterol deficiency as a mechanism for autism: A valproic acid model.

Dysregulated cholesterol metabolism represents an increasingly recognized feature of autism spectrum disorder (ASD). Children with fetal valproate syndrome caused by prenatal exposure to valproic acid (VPA), an anti-epileptic and mood-stabilizing drug, have a higher incidence of developing ASD. However, the role of VPA in cholesterol homeostasis in neurons and microglial cells remains unclear. Therefore, we examined the effect of VPA exposure on regulation of cholesterol homeostasis in the human microglial clone 3 (HMC3) cell line and the human neuroblastoma cell line SH-SY5Y. HMC3 and SH-SY5Y cells were each incubated in increasing concentrations of VPA, followed by quantification of mRNA and protein expression of cholesterol transporters and cholesterol metabolizing enzymes. Cholesterol efflux was evaluated using colorimetric assays. We found that VPA treatment in HMC3 cells significantly reduced ABCA1 mRNA, but increased ABCG1 and CD36 mRNA levels in a dose-dependent manner. However, ABCA1 and ABCG1 protein levels were reduced by VPA in HMC3. Furthermore, similar experiments in SH-SY5Y cells showed increased mRNA levels for ABCA1, ABCG1, CD36, and 27-hydroxylase with VPA treatment. VPA exposure significantly reduced protein levels of ABCA1 in a dose-dependent manner, but increased the ABCG1 protein level at the highest dose in SH-SY5Y cells. In addition, VPA treatment significantly increased cholesterol efflux in SH-SY5Y, but had no impact on efflux in HMC3. VPA differentially controls the expression of ABCA1 and ABCG1, but regulation at the transcriptional and translational levels are not consistent and changes in the expression of these genes do not correlate with cholesterol efflux in vitro.

Comparison of four valproic acid free fraction determination methods used in clinical practice

ObjectiveGiven that hypoalbuminemia tends to result in higher free fraction concentrations of valproic acid, different methods have been developed to determine the latter in patients with this condition. The aim of this study is to assess the reliability of these methods and, if necessary, design a new estimation method. MethodA retrospective analysis was carried out by the Pharmacy Department of Severo Ochoa University Hospital of admitted patients with at least one trough concentration of valproic acid between October 2017 and February 2019. The estimation methods used were those developed by Kodama, Hermida, Doré, as well as a new method proposed in the study. A total of 17 serum valproic acid concentrations were used to determine the free fraction of valproic acid with each method; the values obtained were compared with the results obtained following laboratory determinations. Accuracy and precision were calculated using mean error and root mean square error, respectively. ResultsThe comparison between observed and predicted free valproic acid values using the methods under investigation showed that the method proposed in this study provides the highest reliability as it presents the highest accuracy and precision. The worst results were those obtained using the Kodama method, which does not consider albuminemia, an essential variable that determines the concentration, therapeutic effect and toxicity of valproic acid. ConclusionsGiven that the method proposed in this study proved to be superior to the other methods analyzed, we believe it can be reliably used to estimate free valproic acid levels in patients with hypoalbuminemia.

Interaction between valproic acid and meropenem or ertapenem in patients with epilepsy: clinical relevance and results from pharmaceutical intervention

ObjectiveThe literature has described the interaction between valproic acid and carbapenems. This interaction leads to decreases in plasma concentrations of valproic acid. The main objectives of this study were to assess its relevance in clinical practice, to identify variables associated with increased seizure episode rates, and to analyse the impact of pharmaceutical intervention on avoiding the effects of this interaction. MethodAn observational retrospective study of inpatients with epilepsy admitted between 2016 and 2020. Their pharmacological treatment throughout admission was recorded, and the presence of other interactions leading to decreased plasma concentrations of valproic acid was reviewed. The seizure rate during the year prior to admission was compared to that during the interaction period. For every episode in which the interaction was detected, an intervention was conducted by providing the prescriber with information on the interaction and suggesting a change of antibiotherapy as well as the pharmacokinetic monitoring of valproic acid. Results37 episodes were included. 58.1% of the patients were male and median age was 70 years. In total, 56.8% of the patients received meropenem and 43.2% received ertapenem. The median duration of concomitant treatment with valproic acid and carbapenem was 4 days. The incidence rate ratio was 2.60 (95% confidence interval: 1.61-4.21). Thus, this interaction was associated with a higher seizure rate. A statistically significant association was found between higher seizure rates and patients treated with more than one anti-epileptic drug. Hospital pharmacists detected 24 episodes (64.9%). In total, 17 interventions (70.8%) were accepted and 13 combinations were discontinued. Pharmacokinetic monitoring was conducted in 13 episodes (35.1%) and infratherapeutic levels were found in all of them. ConclusionsThe interaction between valproic acid and meropenem or ertapenem is clinically relevant. It is recommended that this combination should be avoided provided that a viable alternative is available. Pharmaceutical intervention may contribute to preventing seizures associated with this combination.

Association of ABCB1 Polymorphisms with Efficacy and Adverse Drug Reactions of Valproic Acid in Children with Epilepsy.

Genetic polymorphisms in ATP-binding cassette subfamily B member 1 (ABCB1, also known as MDR1) have been reported to be possibly associated with the regulation of response to antiseizure medications. The aim of this study was to investigate the association of ABCB1 polymorphisms with the efficacy of and adverse drug reactions to valproic acid among Chinese children with epilepsy. A total of 170 children from southern China with epilepsy treated with valproic acid for more than one year were recruited, including 61 patients with persistent seizures and 109 patients who were seizure-free. Two single nucleotide polymorphisms of ABCB1, rs1128503 and rs3789243, were genotyped using the Sequenom MassArray system. The two single nucleotide polymorphisms of ABCB1 were found to be significantly associated with treatment outcomes of valproic acid in children with epilepsy. Carriers with the TT genotype of ABCB1 rs1128503 were more inclined to exhibit persistent seizures after treatment with valproic acid (p = 0.013). The CC genotype of rs3789243 was observed to be a potential protective factor for valproic acid-induced gastrointestinal adverse drug reactions (p = 0.018), but possibly increased the risk of valproic acid-induced cutaneous adverse drug reactions (p = 0.011). In contrast, the CT genotype of rs3789243 was associated with a lower risk of valproic acid-induced cutaneous adverse drug reactions (p = 0.011). Haplotype analysis showed that CC haplotype carriers tended to respond better to valproic acid treatment (p = 0.009). Additionally, no significant association was found between ABCB1 polymorphisms and serum concentrations of valproic acid. This study revealed that the polymorphisms and haplotypes of the ABCB1 gene might be associated with the treatment outcomes of valproic acid in Chinese children with epilepsy.

Distribution pattern of UGT1A6 and UGT2B7 gene polymorphism and its impact on the pharmacokinetics of valproic acid and carbamazepine: Prospective genetic association study conducted in Pakistani patients with epilepsy

BackgroundEthnic variation is one of the important factors in clinical practice that may affect the pharmacokinetics of drugs. The present study aims to determine the distribution pattern of UGT1A6 and UGT2B7 gene polymorphism and its possible impact on the metabolism of valproic acid (VPA) and carbamazepine (CBZ) in patients with epilepsy from Khyber Pakhtunkhwa region of Pakistan. Methods: After the enrollment of targeted patients, blood was collected for genotype analysis through Sanger sequencing. Plasma concentrations of VPA and CBZ were determined by reversed-phase high-performance liquid chromatography (HPLC) at the follow-up visit of third month from the initiation of therapy. The drug plasma levels were correlated with different genotypes of UGT1A6 and UGT2B7 to determine the impact of genetic polymorphism on the drug metabolism. Results: Of the total 178 epileptic patients, 120 subjects were prescribed VPA monotherapy while 58 subjects were given CBZ monotherapy. The mean age of the subjects was recorded as 26.1 ± 13.5 years with a predominance of the male gender. Generalized tonic-clonic (GTC) was the most prevalent type of seizure (82%) followed by partial seizure. Genotype analysis revealed that the frequency of homozygous and heterozygous variants of the targeted UGT genes were exceptionally high in the Khyber Pakhtunkhwa population compared to the ethnic groups of other countries. In UGT1A6-A552C and UGT1A6-A541G, AC and AG were the most prevalent genotypes with respective frequencies of 43.2% and 41.1% whereas, in UGT2B7-T161C and UGT2B7-G211T, TC and GG were the most prevalent genotypes with respective frequencies of 42.7% and 99.4%. In the VPA-treated group, the homozygous and heterozygous variants of UGT1A6-A552C and UGT1A6-A541G were significantly associated with lower drug plasma concentrations (p < 0.05). However, none of the genotypes of UGT2B7-T161C revealed any significant association with VPA plasma concentration (p greater than 0.05). In the CBZ-treated group, UGT gene polymorphisms were not recognized to cause alteration in the drug plasma concentrations (p greater than 0.05). Conclusion: The genetic polymorphisms of UGT1A6, but not UGT2B7 significantly affected the plasma levels of valproic acid. The chosen SNPs did not reveal a role in determining the plasma levels of carbamazepine.

Finding a Proper Valproic Acid-Based Autism Spectrum Disorder Model in Zebrafish: Early and Long-term Neurobehavioral Studies

Background: Valproic acid (VPA), which is often used to treat epilepsy, causes a variety of neurobehavioral impairments that closely resemble the phenotype of autism spectrum disorder (ASD) in prenatally exposed individuals. Although the neurobehavioral effects of extremely low concentrations of VPA have received limited research attention, several investigations have shown that the impact of VPA is connected with the concentration and exposure length. Objectives: In the current study, the aim was to find the lowest dose of VPA with the fewest side effects to induce behavioral phenotypes related to ASD in zebrafish. Methods: Zebrafish embryos were first exposed to various concentrations of VPA (i.e., 1, 5, 15, 25, 48, and 75 µM) for 120 hours. Then, 42 days after conception, the survival rate, quality of hatching, and presence of deformity were assessed. Afterward, a 1 µM VPA was chosen based on observations, and behavioral experiments were carried out at 7, 21, and 42 days after fertilization (dpf). Additionally, 7dpf gene expression analysis was evaluated. Results: According to the obtained findings, behavioral abnormalities resembling ASD were induced in 7 and 21 dpf but not in 42 dpf after 120 hours of exposure to 1µM VPA. Real-time analysis in 7 dpf revealed significant changes in a number of genes linked to ASD, including lrp6, gsk3beta, chd8, and ctnnb. Conclusions: In conclusion, 120 hours of exposure of zebrafish embryos to 1 µM of VPA might produce suitable VPA induces autism-like behavior models in zebrafish larvae to research early and long-term neurobehavioral and gene expression alterations. Studies on drug development might adopt this approach.

Prediction of systemic free and total valproic acid by off-line analysis of exhaled breath in epileptic children and adolescents.

Therapeutic drug monitoring (TDM) of medications with a narrow therapeutic window is a common clinical practice to minimize toxic effects and maximize clinical outcomes. Routine analyses rely on the quantification of systemic blood concentrations of drugs. Alternative matrices such as exhaled breath are appealing because of their inherent non-invasive nature. This is especially the case for pediatric patients. We have recently showcased the possibility of predicting systemic concentrations of valproic acid (VPA), an anti-seizure medication by real-time breath analysis in two real clinical settings. This approach, however, comes with the limitation of the patients having to physically exhale into the mass spectrometer. This restricts the possibility of sampling from patients not capable or available to exhale into the mass spectrometer located on the hospital premises. In this work, we developed an alternative method to overcome this limitation by collecting the breath samples in customized bags and subsequently analyzing them by secondary electrospray ionization coupled to high-resolution mass spectrometry (SESI-HRMS). A total ofn= 40 patients (mean ± SD, 11.5 ± 3.5 y.o.) diagnosed with epilepsy and taking VPA were included in this study. The patients underwent three measurements: (i) serum concentrations of total and free VPA, (ii) real-time breath analysis and (iii) off-line analysis of exhaled breath collected in bags. The agreement between the real-time and the off-line breath analysis methods was evaluated using Lin's concordance correlation coefficient (CCC). CCC was computed for ten mass spectral predictors of VPA concentrations. Lin's CCC was >0.6 for all VPA-associated features, except for two low-signal intensity isotopic peaks. Finally, free and total serum VPA concentrations were predicted by cross validating the off-line data set. Support vector machine algorithms provided the most accurate predictions with a root mean square error of cross validation of 29.0 ± 7.4 mg l-1and 3.9 ± 1.4 mg l-1for total and free VPA (mean ± SD), respectively. As a secondary analysis, we explored whether exhaled metabolites previously associated with side-effects and response to medication could be rendered by the off-line analysis method. We found that five features associated with side effects showed a CCC > 0.6, whereas none of the drug response-associated peaks reached this cut-off. We conclude that the clinically relevant free fraction of VPA can be predicted by this combination of off-line breath collection with rapid SESI-HRMS analysis. This opens new possibilities for breath based TDM in clinical settings.

Estimation of mutagenic potential of the valproic acid derivative containing a tertiary amino group

Estimation of mutagenic potential of the valproic acid derivative containing a tertiary amino group

Toxicity and teratogenicity effects of valproic acid on zebrafish (Danio rerio) embryos in relation to autism spectrum disorder.

Valproic acid (VPA) is a widely prescribed antiepileptic drug with various medicinal efficacies. Accumulated evidence implied that prenatal exposure to VPA is highly associated with autism spectrum disorder (ASD). In this study, the zebrafish were exposed to a set of VPA concentrations (0, 5, 10, 20, 40, 80, 160, 320, 640, 1280, and 2560 μM) at 5 h post fertilization (hpf) to 120 hpf. The adverse effects of VPA were extensively studied through the evaluations on the mortality, heartbeats, spontaneous tail coiling, and hatching rate. Morphological observations were conducted at 120 hpf, following the exposure termination. Basic locomotor responses and anxiety-like behavioral alterations evaluated for behavioral impairments are the hallmark feature of ASD. The exposure to VPA at teratogenic concentrations reduced the aforementioned parameters in a dose-dependent manner (p ≤ .05). At the selected non-teratogenic concentrations of VPA, the treated larvae demonstrated profound alterations of basic locomotor responses. No significant changes of anxiety and thigmotactic behaviors were observed on the VPA-treated fish compared to the control (p ≥ .005). This study depicted that embryonic zebrafish exposure to VPA produced significant toxicity and teratogenicity effects as well as the alterations of basic behavioral responses. Overall, this study provides a fundamental insight of the toxicity effects at morphological and behavioral levels to facilitate the understanding of ASD mechanisms at different molecular levels.

The impact of valproic acid and 2-propyl-4-pentenoic acid on antioxidant status measured by GSH/GSSG ratio and FRAP levels in acute and chronic exposure

Valproic acid (VPA) is a broad-spectrum anticonvulsant drug. Its mechanism of action includes enhancing GABAergic transmission, blocking voltage-gated sodium channels, and affecting dopaminergic and serotonergic transmission (1). The mechanism of VPA toxicity, including its effects on the liver, is not fully known. It is assumed that oxidative stress and/or reactive products of drug biotransformation are responsible for its hepatotoxicity (2). The aim of the study was to verify the hypothesis concerning the influence of valproic acid and its metabolite, 2-propyl-4-pentenoic acid (4-en VPA) on the antioxidant status of patients treated with (VPA-T) and poisoned with valproic acid (VPA-P). The VPA-P group was divided into patients with (VPA-Ptox) and without (VPA-Pnon) toxic symptoms observed during the hospitalization. Oxidative stress was assessed using markers, such as antioxidant potential (FRAP) and reduced and oxidised glutathione (GSH/GSSG) ratio were measured in the plasma of the study patients. The obtained results showed statistically significant differences between the concentrations of the drug and its active metabolite levels in the VPA-T and VPA-P groups. In the VPA-P group, the increase of the level of 4-en VPA in the plasma correlated with the increase of the concentration of the drug. The influence of VPA on the antioxidant balance in both groups of patients was demonstrated. The plasma antioxidant potential of FRAP decreased with increasing valproic acid concentrations in the VPA-Ptox group. The lowest concentrations of GSH/GSSG ratio were found in the VPA-Pnon group, without symptoms of intoxication during hospitalization.

Successful LC-MS/MS assay development and validation for determination of valproic acid and its metabolites supporting proactive pharmacovigilance

Valproic acid (VPA) is a well-documented contributor to liver injury, which is likely caused by the formation of its toxic metabolites. Monitoring VPA and its metabolites is very meaningful for the pharmacovigilance, but the availability of a powerful assay is a prerequisite. In this study, for the first time, a sensitive and specific LC-MS/MS method was developed and validated to simultaneously quantify the concentrations of VPA and its six pestering isomer metabolites (3-OH-VPA, 4-OH-VPA, 5-OH-VPA, 2-PGA, VPA-G, and 2-ene-VPA) in human plasma, using 5-OH-VPA-d7 and VPA-d6 as the internal standards (ISs). We also figured out another tricky problem that the concentrations of the parent drug and the metabolites vary widely. Of note, after protein precipitation and dilution with acetonitrile (ACN) and 50% ACN successively, the analytes and the ISs were successfully separated on a Kinetex C18 column. Intriguingly, sacrificing its signal intensity by elevated collision energy of VPA finally achieved the simultaneous determination. As expected, the method showed great linearity (r > 0.998) over the concentration ranges for all analytes. The inter-day and intra-day accuracy and precision were both acceptable. The method was successfully applied in 127 children with epilepsy. This novel assay will support the VPA-associated pharmacovigilance in the future.

Retinoic acid signaling pathway perturbation impacts mesodermal-tissue development in the zebrafish embryo: Biomarker candidate identification using transcriptomics.

The zebrafish embryo (ZE) model provides a developmental model well conserved throughout vertebrate embryogenesis, with relevance for early human embryo development. It was employed to search for gene expression biomarkers of compound-induced disruption of mesodermal development. We were particularly interested in the expression of genes related to the retinoic acid signaling pathway (RA-SP), as a major morphogenetic regulating mechanism. We exposed ZE to teratogenic concentrations of valproic acid (VPA) and all-trans retinoic acid (ATRA), using folic acid (FA) as a non-teratogenic control compound shortly after fertilization for 4 h, and performed gene expression analysis by RNA sequencing. We identified 248 genes specifically regulated by both teratogens but not by FA. Further analysis of this gene set revealed 54 GO-terms related to the development of mesodermal tissues, distributed along the paraxial, intermediate, and lateral plate sections of the mesoderm. Gene expression regulation was specific to tissues and was observed for somites, striated muscle, bone, kidney, circulatory system, and blood. Stitch analysis revealed 47 regulated genes related to the RA-SP, which were differentially expressed in the various mesodermal tissues. These genes provide potential molecular biomarkers of mesodermal tissue and organ (mal)formation in the early vertebrate embryo.

Decreased serum concentrations of antiseizure medications in children with drug resistant epilepsy following treatment with ketogenic diet.

To examine the potential influence of a ketogenic diet on serum concentrations of antiseizure medications (ASMs) in children with drug resistant epilepsy. We investigated the serum concentrations of ASMs in 25 children with drug resistant epilepsy, 2-13 years of age, treated with a classical ketogenic diet for 12 weeks. The patients were recruited from the National Centre for Epilepsy from August 15th, 2017, to January 24th, 2022. Changes in ASM serum concentrations were analyzed using a mixed effect model analysis. Significance level was set at P < 0.05 for all comparisons. The participants used 12 different ASMs during the study. The mean number of ASMs was 2.4 (±SD 0.7). None of the participants changed the type or dose of the ASMs during the intervention period. The serum concentrations of clobazam (n = 9, P = 0.002), desmethylclobazam (n = 9, P = 0.010), and lamotrigine (n = 6, P = 0.016) decreased significantly during the dietary treatment. The analytes with the largest reduction in serum concentration after 12 weeks of dietary treatment were clobazam (mean change -38%) and desmethylclobazam (mean change -37%). We found no significant change in the serum concentrations of levetiracetam, topiramate, and valproic acid. We identified a significant decrease in the serum concentrations of clobazam, desmethylclobazam, and lamotrigine following a 12-week ketogenic diet intervention in children with drug resistant epilepsy. An unintended decrease in the serum concentrations of ASMs may render the patient prone to seizures. Measurements of ASM serum concentrations might be useful in patients on a ketogenic diet, especially in patients with lack of efficacy of the dietary treatment.

Diagnosis and prognosis of serum Fut8 for epilepsy and refractory epilepsy in children.

With adequate serum concentration of antiepileptic drugs, the epilepsy symptoms in many patients still cannot be controlled well. The alteration of glycosyltransferase has obvious influence on the pathogenesis of epilepsy. In this study, we focus on the diagnostic and prognostic value of fucosyltransferase 8 (Fut8) on epilepsy and refractory epilepsy. Serum samples of 199 patients with epilepsy, 59 patients with refractory epilepsy and 22 healthy controls who were diagnosed in Shenzhen Children's hospital from August 2018 to August 2019 were collected. The level of lectins was further analyzed by lectin chip and enzyme linked immunosorbent assay (ELISA). The diagnostic value of serum Fut8 for epilepsy and refractory epilepsy was evaluated by receiver operating characteristic curve. Finally, the difference in the recurrence rate of convulsion in patients with epilepsy or refractory epilepsy within 2 years were observed in different Fut8 expression patients. The concentration of valproic acid (VPA) were significant different between epilepsy and refractory epilepsy group. The expression of α1, 6-fucosylation and Fut8 was significantly increased in the refractory epilepsy group compared with healthy controls. The area under the curve of Fut8 as a biomarker for predicting epilepsy or refractory epilepsy was 0.620 and 0.856, respectively. There was a significant difference in the recurrence rate of convulsion within 2 years in the children with refractory epilepsy (p = 0.0493) not epilepsy (p = 0.1865) between the high and low Fut8 expression groups. Fut8 was one of the effective indicators for the diagnosis and prognosis of refractory epilepsy.

Embryonic exposure to acetyl-L-carnitine protects against valproic acid-induced cardiac malformation in zebrafish model.

Worldwide, estimated counts of about 7.9 million children are born with serious birth defects. In addition to genetic factors, prenatal exposure to drugs and environmental toxicants represents a major contributing factor to congenital malformations. In earlier investigation, we explored cardiac malformation caused by valproic acid (VPA) during early developing stages of zebrafish. Since heart depends on mitochondrial fatty acid oxidative metabolism for energy demands in which carnitine shuttle has a major role, the present study aimed to investigate the effect of acetyl-L-carnitine (AC) against VPA-induced cardiac malformation in developing zebrafish. Initially, AC was subjected to toxicological evaluation, and two micromolar concentrations (25µM and 50µM) were selected for evaluation. A sub-lethal concentration of VPA (50µM) was selected to induce cardiac malformation. The embryos were grouped and the drug exposures were made at 2.5h post-fertilization (hpf). The cardiac development and functioning was monitored. A progressive decline in cardiac functioning was noted in group exposed to VPA 50µM. At 96 hpf and 120 hpf, the morphology of heart was severely affected with the chambers which became elongated and string-like accompanied by histological changes. Acridine orange staining showed accumulation of apoptotic cells. Group exposed to VPA 50µM with AC 50µM showed a significant reduction in pericardial sac edema with morphological, functional and histological recovery in developing heart. Moreover, reduced number of apoptotic cells was noted. The improvement with AC might be due to restoration of carnitine homeostasis for cardiac energy metabolism in developing heart.

A novel method for predicting the unbound valproic acid concentration

In this study, we constructed a prediction formula for unbound valproic acid (VPA) concentration that was more accurate and widely applicable than previously reported formulae. A total of 136 datasets from 75 patients were analyzed retrospectively. The median of free fraction of VPA was 0.16 (interquartile range: 0.07; range: 0.07–0.45). The parameter that combined total VPA concentration (CtVPA) and serum albumin (SA), (CtVPA [μM] – 2 × SA [μM]), was significantly related to the free fraction of VPA (r = 0.76, p < 0.001). We constructed a combined parameter-based prediction formula for unbound VPA concentration. Analysis using external datasets from patients without severe renal failure showed that the prediction errors of the unbound VPA concentration were lower than those of previously reported formulae. Although the previous formulae showed large prediction errors, especially in the specific range of CtVPA values, the constructed formula showed a weak trend with CtVPA or SA. The formula based on (CtVPA [μM] – 2 × SA [μM]) had high prediction accuracy and wide applicability in predicting the unbound VPA concentration in patients without severe renal failure.