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.

In Situ and Individual-Based Analysis of the Influence of Polystyrene Microplastics on Escherichia coli Conjugative Gene Transfer at the Single-Cell Level.

The impact of microplastic particles of micro- and nanometer sizes on microbial horizontal gene transfer (HGT) remains a controversial topic. Existing studies rely on traditional approaches, which analyze population behavior, leading to conflicting conclusions and a limited understanding. The present study addressed these limitations by employing a novel microfluidic chamber system for in situ visualization and precise quantification of the effects of different concentrations of polystyrene (PS) microbeads on microbial HGT at the single-cell level. The statistical analysis indicated no significant difference in the division times of both the donor and recipient bacteria across different PS microbead concentrations. However, as the concentration of PS microbeads increased from 0 to 2000 mg L-1, the average conjugation frequency of Escherichia coli decreased from 0.028 ± 0.015 to 0.004 ± 0.003. Our observations from the microfluidic experiments revealed that 500 nm PS microbeads created a barrier effect on bacterial conjugative transfer. The presence of microbeads resulted in reduced contact and interaction between the donor and recipient strains, thereby causing a decrease in the conjugation transfer frequency. These findings were validated by an individual-based modeling framework parameterized by the data from the individual-level microfluidic experiments. Overall, this study offers a fresh perspective and strategy for investigating the risks associated with the dissemination of antibiotic resistance genes related to microplastics.

Phenotypic and genomic analysis of inulin consumption by Lactiplantibacillus plantarum strains from Sichuan pickle.

AIMS: To investigate the capability, properties, and molecular mechanism of inulin fermentation by lactic acid bacteria (LAB) from Sichuan pickle. METHODS AND RESULTS: A total of 79 LAB strains were purified from 30 aged Sichuan pickle brine samples, and only 21 Lactiplantibacillus plantarum strains (26.58%, 21/79) derived from 15 samples grew well through utilizing inulin as a carbon source. The fermentation tests through using long-chain inulin (lc-inulin) as a carbon source showed that only 6 L. plantarum strains grew well, while other 15 strains could only utilize short-chain oligofructose (FOS), and thin-layer chromatography analysis evidenced a strain specificity of inulin consumption patterns. Lactiplantibacillus plantarum YT041 is a vigorous inulin fermenter, and whole genome sequencing data revealed that sacPTS1 and fosRABCDXE operons might be associated with the fermentation of FOS and lc-inulin, respectively. CONCLUSIONS: The phenotype of inulin consumption is commonly present in LAB from Sichuan pickle, which is strain-specific and largely depends on their specific ecological niche and degree of polymerization.

Global genome and comparative transcriptomic analysis reveal the inulin consumption strategy of Lactiplantibacillus plantarum QS7T.

Sichuan pickle is a natural combination of probiotics and dietary fibers, in which a strain Lactiplantibacillus plantarum QS7T was found to be capable of efficiently metabolizing inulin. However, the underlying molecular mechanism of inulin consumption by the strain QS7T is unclear. Therefore, this study firstly investigated the metabolic characteristics of inulin in the strain QS7T, and the results showed it could grow very well on the medium containing inulin as a carbon source (maximum OD600 nm, 1.891 ± 0.028) and degrade both short-chain oligofructose and long-chain fructan components through thin layer chromatography analysis. Genomic sequencing and analysis revealed a high percentage of functional genes associated with carbohydrate transport and metabolism, particularly glycoside hydrolase (GH) genes responsible for hydrolysing carbohydrates, within the genome of the strain QS7T. Furthermore, comparative transcriptomic analysis of L. plantarum QS7T in response to inulin or glucose indicated that functional genes associated with inulin consumption including several genes encoding PTS sugar transporters and two predicted GH32 family genes encoding beta-fructofuranosidase and beta-fructosidase were significantly up-regulated by inulin compared to the gene expression on glucose. In conclusion, we obtained a mechanistic understanding of interplay between probiotic L. plantarum QS7T derived from Sichuan pickle and natural dietary fiber, inulin; totally two operons including a sacPTS1 operon responsible for metabolizing short-chain oligofructose primarily in the cytoplasm and a fos operon responsible for extracellularly degrading all moderate and long-chain fructan components linked to inulin consumption by L. plantarum QS7T.

Prebiotics Inulin Metabolism by Lactic Acid Bacteria From Young Rabbits.

Inulin as a commercial prebiotic could selectively promote the growth of beneficial gut microbes such as lactic acid bacteria (LAB). Whether LAB in rabbit gut possesses the capability to metabolize and utilize inulin is little known. Therefore, this study recovered 94 LAB strains from neonate rabbits and found that only 29% (28/94) could metabolize inulin with both species- and strain-specificity. The most vigorous inulin-degrading strain, Lacticaseibacillus paracasei YT170, could efficiently utilize both short-chain and long-chain components through thin-layer chromatography analysis. From genomic analysis, a predicted fosRABCDXE operon encoding putative cell wall-anchored fructan ß-fructosidase, five fructose-transporting proteins and a pts1BCA operon encoding putative ß-fructofuranosidase and sucrose-specific IIBCA components were linked to long-chain and short-chain inulin utilization respectively. This study provides a mechanistic rationale for effect of inulin administration on rabbits and lays a foundation for synbiotic applications aimed at modulating the intestinal microbiota of young rabbits.