Population pharmacokinetics of valproic acid in children with epilepsy: Implications for dose tailoring when switching from oral syrup to sustained-release tablets.

Significant pharmacokinetic (PK) differences exist between different forms of valproic acid (VPA), such as syrup and sustained-release (SR) tablets. This study aimed to develop a population pharmacokinetic (PopPK) model for VPA in children with epilepsy and offer dose adjustment recommendation for switching dosage forms as needed. The study collected 1411 VPA steady-state trough concentrations (Ctrough) from 617 children with epilepsy. Using NONMEM software, a PopPK model was developed, employing a stepwise approach to identify possible variables such as demographic information and concomitant medications. The final model underwent internal and external evaluation via graphical and statistical methods. Moreover, Monte Carlo simulations were used to generate a dose tailoring strategy for typical patients weighting 20-50 kg. As a result, the PK characteristics of VPA were described using a one-compartment model with first-order absorption. The absorption rate constant (ka) was set at 2.64 and 0.46 h-1 for syrup and SR tablets. Body weight and sex were identified as significant factors affecting VPA's pharmacokinetics. The final PopPK model demonstrated acceptable prediction performance and stability during internal and external evaluation. For children taking syrup, a daily dose of 25 mg/kg resulted in the highest probability of achieving the desired target Ctrough, while a dose of 20 mg/kg/day was appropriate for those taking SR tablets. In conclusion, we established a PopPK model for VPA in children with epilepsy to tailor VPA dosage when switching between syrup and SR tablets, aiming to improve plasma VPA concentrations fluctuations.

Lipidomics study of Liujunzi decoction in hyperlipidemia rats with spleen deficiency based on UPLC-Q-TOF/MS.

Hyperlipidemia refers to the abnormal levels of triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) in peripheral blood circulation. It is a predominant risk factor underlying cardiovascular and cerebrovascular diseases, including coronary heart disease and atherosclerosis. Furthermore, it is also one of the most prevalent chronic diseases globally. Liujunzi Decoction is the basic prescription for the treatment of spleen and stomach diseases. It can tonify the spleen and qi, remove dampness, and reduce turbidity. Moreover, it is also clinically used for the treatment of spleen deficiency hyperlipidemia. However, its metabolites and therapeutic effect on spleen deficiency hyperlipidemia have not been comprehensively determined in vitro and in vivo. This study established a rat model of spleen deficiency hyperlipidemia by inducing starvation and satiety disorders, exhaustion swimming, and intragastric administration of the fat emulsion. To identify related metabolite changes and serum lipid composition, UPLC-Q-TOF-MS, PCA, and OPLS-DA lipidological methods were performed. The results demonstrated significant changes in rat's signs during the modeling process, which were consistent with the criteria for the syndrome differentiation of spleen deficiency in traditional Chinese medicine. Furthermore, this study identified 100 potential biomarkers in rat serum, of which 52 were associated with lipid synthesis, such as LPC, PC, PI, PE, PA, Cer, SM, etc. The pathways involved were glycerol phospholipid, sphingomyelin, and glycerol ester metabolisms. After the Liujunzi decoction intervention, 56 potential biomarkers were observed in the high-dose group, alleviating the metabolic spectrum imbalance by reducing metabolite levels. In addition, metabolic pathway disturbances were markedly improved. This study provides references for future studies on Liujunzi decoction and furnishes essential data for assessing the relationships between chemical constituents and pharmacological activities of Liujunzi decoction.

LC-MS/MS and EMIT measure the whole blood concentration of cyclosporine A: The two methods yield concordant results within the dynamic range of the latter, but the former shows broader application scenarios.

Cyclosporine A (CsA) is a widely used immunosuppressive drug with a narrow therapeutic index and large individual differences. Its therapeutic and toxic effects are closely related to blood drug concentrations, requiring routine therapeutic drug monitoring (TDM). The current main methods for TDM of CsA are enzyme multiplied immunoassay technique (EMIT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). However, few study on the method comparison of the EMIT and LC-MS/MS for the measurement of whole blood CsA concentration in children has been reported. In this study, we developed a simple and sensitive LC-MS/MS assay for the determination of CsA, and 657 cases of CsA concentrations were determined from 197 pediatric patients by a routine EMIT assay and by the validated in-house LC-MS/MS method on the same batch of samples, aimed to address the aforementioned concern. Consistency between the two assays was evaluated using linear regression and Bland-Altman analysis. The linear range of LC-MS/MS was 0.500-2000 ng/mL and that of the EMIT was 40-500 ng/mL, respectively. Overall, the correlation between the two methods was significant (r-value ranging from 0.8842 to 0.9441). Unsatisfactory consistency was observed in the concentrations < 40 ng/mL (r = 0.7325) and 200-500 ng/mL (r = 0.6851). Bland-Altman plot showed a mean bias of -18.0 % (±1.96 SD, -73.8 to 37.8 %) between EMIT and LC-MS/MS. For Passing-Bablok regression between EMIT and LC-MS/MS did not differ significantly (p > 0.05). In conclusion, the two methods were closely correlated, but the CsA concentration by LC-MS/MS assay was slightly higher than that by EMIT method. Switching from the EMIT assay to the LC-MS/MS method was acceptable, and the LC-MS/MS method will receive broader application in clinical settings due to its better analytical capabilities, but the results need to be further verified in different laboratories.

Cordycepin alleviates hepatic fibrosis in association with the inhibition of glutaminolysis to promote hepatic stellate cell senescence.

Cordycepin (CRD) is an active component derived from Cordyceps militaris, which possesses multiple biological activities and uses in liver disease. However, whether CRD improves liver fibrosis by regulating hepatic stellate cell (HSC) activation has remained unknown. The study aims further to clarify the activities of CRD on liver fibrosis and elucidate the possible mechanism. Our results demonstrated that CRD significantly relieved hepatocyte injury and inhibited HSC activation, alleviating hepatic fibrogenesis in the Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC)-induced mice model. In vitro, CRD exhibited dose-dependent repress effects on HSC proliferation, migration, and pro-fibrotic function in TGF-ß1-activated LX-2 and JS-1 cells. The functional enrichment analysis of RNA-seq data indicated that the pathway through which CRD alleviates HSC activation involves cellular senescence and cell cycle-related pathways. Furthermore, it was observed that CRD accumulated the number of senescence-associated a-galactosidase positive cells and the levels of senescencemarker p21, and provoked S phasearrestof activated HSC. Remarkably, CRD treatment abolished TGF-ß-induced yes-associated protein (YAP) nuclear translocation that acts upstream of glutaminolysis in activated HSC. On the whole, CRD significantly inhibited glutaminolysis of activated-HSC and induced cell senescence through the YAP signaling pathway, consequently alleviating liver fibrosis, which may be a valuable supplement for treating liver fibrosis.

Individualized atomoxetine response and tolerability in children with ADHD receiving different dosage regimens: the need for CYP2D6 genotyping and therapeutic drug monitoring to dance together.

Integrating CYP2D6 genotyping and therapeutic drug monitoring (TDM) is crucial for guiding individualized atomoxetine therapy in children with attention-deficit/hyperactivity disorder (ADHD). The aim of this retrospective study was (1) to investigate the link between the efficacy and tolerability of atomoxetine in children with ADHD and plasma atomoxetine concentrations based on their CYP2D6 genotypes; (2) to offer TDM reference range recommendations for atomoxetine based on the CYP2D6 genotypes of children receiving different dosage regimens. This retrospective study covered children and adolescents with ADHD between the ages of 6 and <18, who visited the psychological and behavioral clinic of Children's Hospital of Nanjing Medical University from June 1, 2021, to January 31, 2023. The demographic information and laboratory examination data, including CYP2D6 genotype tests and routine TDM of atomoxetine were obtained from the hospital information system. We used univariate analysis, Mann-Whitney U nonparametric test, Kruskal-Wallis test, and the receiver operating characteristic (ROC) curve to investigate outcomes of interest. 515 plasma atomoxetine concentrations of 385 children (325 boys and 60 girls) with ADHD between 6 and 16 years of age were included for statistical analysis in this study. Based on genotyping results, >60% of enrolled children belonged to the CYP2D6 extensive metabolizer (EM), while <40% fell into the intermediate metabolizer (IM). CYP2D6 IMs exhibited higher dose-corrected plasma atomoxetine concentrations by 1.4-2.2 folds than those CYP2D6 EMs. Moreover, CYP2D6 IMs exhibited a higher response rate compare to EMs (93.55% vs 85.71%, P = 0.0132), with higher peak plasma atomoxetine concentrations by 1.67 times than those of EMs. Further ROC analysis revealed that individuals under once daily in the morning (q.m.) dosing regimen exhibited a more effective response to atomoxetine when their levels were ≥ 268 ng/mL (AUC = 0.710, P < 0.001). In addition, CYP2D6 IMs receiving q.m. dosing of atomoxetine were more likely to experience adverse reactions in the central nervous system and gastrointestinal system when plasma atomoxetine concentrations reach 465 and 509 ng/mL, respectively. The findings in this study provided promising treatment strategy for Chinese children with ADHD based on their CYP2D6 genotypes and plasma atomoxetine concentration monitoring. A peak plasma atomoxetine concentration higher than 268 ng/mL might be requisite for q.m. dosing. Assuredly, to validate and reinforce these initial findings, it is necessary to collect further data in controlled studies with a larger sample size.

From "wet" matrices to "dry" blood spot sampling strategy: a versatile LC-MS/MS assay for simultaneous monitoring caffeine and its three primary metabolites in preterm infants.

OBJECTIVES: To update traditional "wet" matrices to dried blood spot (DBS) sampling, based on the liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) technique, and develop a method for simultaneous analyzing caffeine and its three primary metabolites (theobromine, paraxanthine, and theophylline), supporting routine therapeutic drug monitoring (TDM) for preterm infants. METHODS: DBS samples were prepared by a two-step quantitative sampling method, i.e., volumetric sampling of a quantitative 10 µL volume of peripheral blood and an 8 mm diameter whole punch extraction by a methanol/water (80/20, v/v) mixture containing 125 mM formic acid. Four paired stable isotope labeled internal standards and a collision energy defect strategy were applied for the method optimization. The method was fully validated following international guidelines and industrial recommendations on DBS analysis. Cross validation with previously developed plasma method was also proceeded. The validated method was then implemented on the TDM for preterm infants. RESULTS: The two-step quantitative sampling strategy and a high recovery extraction method were developed and optimized. The method validation results were all within the acceptable criteria. Satisfactory parallelism, concordance, and correlation were observed between DBS and plasma concentrations of the four analytes. The method was applied to provide routine TDM services to 20 preterm infants. CONCLUSIONS: A versatile LC-MS/MS platform for simultaneous monitoring caffeine and its three primary metabolites was developed, fully validated, and successfully applied into the routine clinical TDM practices. Sampling method switching from "wet" matrices to "dry" DBS will facilitate and support the precision dosing of caffeine for preterm infants.

COL6A3 promotes cellular malignancy of osteosarcoma by activating the PI3K/AKT pathway

SUMMARY OBJECTIVE In this study, we aimed to investigate the role of COL6A3 on cell motility and the PI3K/AKT signaling pathway in osteosarcoma. METHODS The relative expression of COL6A3 was achieved from a GEO dataset in osteosarcoma tissue. siRNA technology was applied to decrease the COL6A3 expression in cells, and cell counting kit-8 (CCK-8) assay and colony formation analysis were used to examine the cell proliferation potential. Knockdown COL6A3 made the proliferation and colony formation abilities worse than the COL6A3 without interference. Likewise, in contrast to the si-con group, cell invasion and migration were inhibited in the si-COL6A3 group. Moreover, the western blot results suggested that the PI3K/AKT signaling pathway was manipulated by measuring the protein expression of the PI3K/AKT pathway-related markers, due to the COL6A3 inhibition. CONCLUSION COL6A3 plays a crucial role in modulating various aspects of the progression of osteosarcoma, which would provide a potentially effective treatment for osteosarcoma.

RESUMO OBJETIVO Neste estudo, investigamos a função do COL6A3 na mobilidade celular e na via PI3K/AKT em osteossarcomas. METODOLOGIA A expressão relativa do COL6A3 foi obtida a partir de dados GEO em tecidos de osteossarcoma. O RNA de interferência (siRNA) foi utilizado para reduzir a expressão do COL6A3 nas células, e o teste de contagem de células kit-8 (CCK-8) e a análise de formação de colônias foram realizados para examinar o potencial de proliferação celular. Além disso, o Transwell comprovou os efeitos do si-COL6A3 na invasão celular e migração em células de osteossarcoma. Para medir os níveis de expressão das proteínas e mRNAs, utilizamos transcriptase reversa quantitativa (qRT-PCR) e western blot. RESULTADOS O COL6A3 foi regulado nos tecidos e células do osteossarcoma quando comparado com o controle normal. A redução de COL6A3 reduziu a proliferação e a capacidades de formação de colônias em relação ao COL6A3 sem interferência. Do Mesmo modo, ao contrário do observado no grupo si-con, a invasão e migração celular foram inibidas no grupo si-COL6A3. Além disso, o resultado do western blot sugere que a via PI3K/AKT foi manipulada, medindo a expressão proteica dos marcadores relacionados à PI3K/AKT, devido à inibição do COL6A3. CONCLUSÃO O COL6A3 desempenha um papel crucial na modulação de vários aspectos da progressão do osteossarcoma, o que pode representar um possível tratamento eficaz para a doença.