Valproic Acid Concentrations Research Articles

Effect of Wuling powder on the pharmacokinetics of valproic acid in epileptic rats

Purpose: To investigate the effect of Wuling powder (WP) on the pharmacokinetics of valproic acid (VPA) in epileptic rats.Methods: A model of epilepsy was established in SD rats by intraperitoneal injection of pentylenetetrazole (PTZ). Twelve epileptic rats were randomly divided into two groups: control group given oral VPA alone at a dose of 180 mg/kg VPA, and drug combination group orally given VPA (180 mg/kg) co-administered with WP at a dose of 200 mg/kg. Blood sample (0.5 mL) was collected at 15, 30, 60, 120, 240 and 720 min after drug administration for measurement of plasma concentrations of VPA using ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).Results: The AUC (0-480min) and maximum plasma concentrations (Cmax) of VPA in the drug combination group were significantly higher than those in the control group (p < 0.01). The half-time (t1/2) and time taken to attain maximum plasma VPA concentration (Tmax) in the combination group were extended, when compared to control group (p < 0.05).Conclusion: These results demonstrate that WP increases the plasma concentration of VPA and affects the pharmacokinetic properties of VPA in epileptic rats. Thus, the pharmacodynamic influence of this interaction should be taken into consideration while prescribing WP to epileptic patients already taking VPA.

Investigating the synergic effects of valproic acid and crocin on BDNF and GDNF expression in epidermal neural crest stem cells

Following nerve tissue damage, various events, such as inflammatory responses, microglial activation, endoplasmic reticulum stress, and apoptosis, can occur, which all lead to cell death, prevent axonal growth, and cause axonal circumvolution. So far, several researchers have tended to adopt strategies to reduce the harmful conditions associated with neurological disorders, and stem‑cell‑based therapy is one of those promising strategies. Epidermal neural crest stem cells (EPI‑NCSCs) are a type of stem cell that has widely been employed for the treatment of various neurological disorders. It has been suggested that these stem cells perform their supportive actions primarily through the release of different neurotrophic factors. Hence, in this study, the neuroprotective impacts of valproic acid (VPA) and crocin were evaluated on the mRNA expression levels of brain‑derived neurotrophic factor (BDNF) and glial‑cell‑derived neurotrophic factor (GDNF) in EPI‑NCSCs. In this research, we isolated EPI‑NCSCs from the hair follicles of the rat whisker pad. Then, the cells were treated with different concentrations of VPA and crocin for 72 h. Subsequently, an MTT assay was performed to define the suitable concentrations of drugs. Finally, real‑time PCR was performed to evaluate the mRNA expression levels of BDNF and GDNF in these stem cells. The results of the MTT assay showed that the treatment of EPI‑NCSCs with 1 mM VPA and 1.5 mM crocin, and the co‑treatment with 1 mM VPA and 500 μM crocin, led to the survival and proliferation of these stem cells. Moreover, the real‑time PCR results revealed that both VPA and crocin, both individually and in combination, can significantly increase the expression levels of BDNF and GDNF in EPI‑NCSCs. According to the findings of this study, both VPA and crocin, alone and in combination, are potential candidates for enhancing the capacity of EPI‑NCSCs to differentiate into neural lineages. Therefore, the co‑treatment of EPI‑NCSCs with these drugs can be employed for the treatment of various neurological disorders, such as spinal cord injury.

Combined Method of Neuronal Cell-Inducible Vector and Valproic Acid for Enhanced Gene Expression under Hypoxic Conditions.

Gene therapy shows the ability to restore neuronal dysfunction via therapeutic gene expression. The efficiency of gene expression and delivery to hypoxic injury sites is important for successful gene therapy. Therefore, we established a gene/stem cell therapy system using neuron-specific enolase promoter and induced neural stem cells in combination with valproic acid to increase therapeutic gene expression in hypoxic spinal cord injury. To examine the effect of combined method on enhancing gene expression, we compared neuronal cell-inducible luciferase levels under normoxia or hypoxia conditions in induced neural stem cells with valproic acid. Therapeutic gene, vascular endothelial growth factor, expression with combined method was investigated in hypoxic spinal cord injury model. We verified gene expression levels and the effect of different methods of valproic acid administration in vivo. The results showed that neuron-specific enolase promoter enhanced gene expression levels in induced neural stem cells compared to Simian Virus 40 promoter under hypoxic conditions. Valproic acid treatment showed higher gene expression of neuron-specific enolase promoter than without treatment. In addition, gene expression levels and cell viability were different depending on the various concentration of valproic acid. The gene expression levels were increased significantly when valproic acid was directly injected with induced neural stem cells in vivo. In this study, we demonstrated that the combination of neuron-specific enolase promoter and valproic acid induced gene overexpression in induced neural stem cells under hypoxic conditions and also in spinal cord injury depending on valproic acid administration in vivo. Combination of valproic acid and neuron-specific enolase promoter in induced neural stem cells could be an effective gene therapy system for hypoxic spinal cord injury.

Abstract 272: Dose Optimization of Early High-Dose Valproic Acid for Neuroprotection After Cardiac Arrest

Introduction: High-dose valproic acid (VPA) has been shown to improve the survival and neurologic outcomes in preclinical brain injury models including asphyxial cardiac arrest (CA) in rats. However, its pharmacokinetics, pharmacodynamics, and safety profiles in large animal CA models are unknown. Hypothesis: High-dose VPA can be safely administered after return of spontaneous circulation (ROSC) and cross the blood-brain barrier dose-dependently in a swine CA model. Methods: After 8 minutes of untreated ventricular fibrillation CA, male Yorkshire swine [43.3 (3.0) kg] were resuscitated for up to 16 minutes until ROSC. They were randomized to receive placebo, 75 mg/kg, 150 mg/kg, or 300 mg/kg VPA as 90-minute intravenous infusion (n=5 per group) beginning 20 minutes after sustained ROSC. Animals were monitored for 2 additional hours after infusion ended and then euthanized. Experimental operators were blinded to the treatments. Results: The mean total cardiac arrest duration was 15.0 (1.6) minutes, with no significant differences between groups. At end of infusion, the serum free VPA concentration increased dose dependently, from 139.2 (10.1) mcg/mL [75 mg/kg VPA] to 287.2 (24.6) mcg/mL [150 mg/kg VPA] to 565.6 (36.5) mcg/mL [300 mg/kg VPA] (p&lt;0.05). This corresponded to a dose-dependent decrease in the fraction of serum protein-bound VPA, from 41.8% (1.8) [75 mg/kg VPA] to 23.4% (3.8) [150 mg/kg VPA] to 14.4% (3.8) [300 mg/kg VPA] (p&lt;0.05). Brain total VPA concentrations at end of experiment were 26.1 (3.1) mcg/g [75 mg/kg VPA], 72.5 (18.9) mcg/g [150 mg/kg VPA], and 212.3 (33.4) mcg/g [300 mg/kg VPA] (p&lt;0.05). There was a strong linear correlation between serum free VPA and brain total VPA concentrations (R 2 =0.98). All animals survived until euthanasia, although the 300 mg/kg group required more epinephrine to maintain mean arterial pressure greater than or equal to 80 mmHg and had higher lactic acidosis. Conclusion: Brain VPA concentrations correlate strongly with serum free VPA when high-dose intravenous VPA is given after ROSC in a swine CA model. These results provide the foundation for dose-optimization studies of high-dose VPA as a neuroprotective therapy following resuscitation from CA.

Pharmacokinetic interaction of brivaracetam on other antiepileptic drugs in adults with focal seizures: Pooled analysis of data from randomized clinical trials

ObjectiveTo assess the effect of brivaracetam (BRV) on steady-state plasma concentrations of commonly prescribed antiepileptic drugs (AEDs). MethodsData were pooled from five randomized, double-blind, placebo-controlled efficacy studies (NCT00175929, NCT00175825, NCT00490035, NCT00464269, and NCT01261325) in which adults with refractory epilepsy, and receiving stable doses of 1–2 AEDs, initiated adjunctive treatment with BRV (or placebo) for up to 12 weeks, following a 4–8 week baseline period. Concentrations of carbamazepine, carbamazepine epoxide, clobazam, clonazepam, lacosamide, lamotrigine, levetiracetam, oxcarbazepine (MHD), phenobarbital, phenytoin, pregabalin, topiramate, valproic acid and zonisamide, were measured during baseline and during BRV or placebo evaluation periods. Log-transformed data for patients receiving BRV dosages of 50–200 mg/day (or placebo) were evaluated using repeated measures analysis of covariance. Geometric least-squares means ratios of respective AED concentrations (treatment vs baseline) and their 90% confidence intervals (CIs) were calculated. Relevant interaction of BRV on the respective AED was inferred if CIs were entirely outside of 0.80–1.25 limits. ResultsWithin the population for analysis (n = 1402), relevant interaction was observed for carbamazepine epoxide alone which increased up to 2-fold from baseline due to inhibition of epoxide hydrolase by BRV, and the effect size was not influenced by concomitant valproic acid. Relevant interaction was not observed for other AEDs. ConclusionIn adults with focal seizures, adjunctive BRV treatment does not affect plasma concentrations of the evaluated AEDs but increases carbamazepine epoxide metabolite. Carbamazepine dose reduction should be considered if tolerability issues arise.

Combination of Olanzapine and Samidorphan Has No Clinically Significant Effect on the Pharmacokinetics of Lithium or Valproate.

Background and ObjectiveOlanzapine is an atypical antipsychotic indicated for the treatment of schizophrenia and, either as monotherapy or as an adjunct to lithium or valproate, for bipolar I disorder. Multiple daily doses of olanzapine do not affect the pharmacokinetics of lithium or valproate; therefore, concomitant olanzapine administration does not require dosage adjustment of lithium or valproate. ALKS 3831, a combination of olanzapine and the opioid receptor antagonist samidorphan (OLZ/SAM), is currently under development to provide the established antipsychotic efficacy of olanzapine while mitigating olanzapine-induced weight gain. Olanzapine is recognized as one of the most efficacious antipsychotics; however, the benefits of olanzapine are offset by its propensity to cause significant weight gain, which may lead to long-term metabolic sequelae. This study evaluated the effects of multiple daily doses of OLZ/SAM on the pharmacokinetics of lithium or valproate in healthy subjects.MethodsThis was an open-label, single-sequence, two-cohort study (ALKS3831-B101) conducted at a single center in the USA. Thirty-four healthy adult subjects were assigned (1:1) to receive lithium carbonate 300-mg tablets (cohort 1) or divalproex sodium 500-mg tablets (cohort 2), once every 12 h on days 1–7. Once-daily oral doses of OLZ/SAM (olanzapine 10 mg/samidorphan 10 mg) bilayer tablets were administered on days 8–18. Subjects resumed every 12-h doses of lithium or valproate concomitantly with the once-daily oral doses of OLZ/SAM on days 12–18. Plasma concentrations of lithium and valproic acid (valproate) were quantified in blood samples collected prior to and up to 12 h after lithium or valproate dose administration on days 7 and 18. Pharmacokinetic parameters of lithium and valproate, including maximum plasma concentration and area under the plasma concentration–time curve over a 12-h dosing interval, were calculated. The ratio of geometric means of maximum plasma concentration and area under the plasma concentration–time curve over a 12-h dosing interval in the presence and absence of OLZ/SAM, and its two-sided 90% confidence intervals, were derived from a mixed-effects model. Adverse events were monitored throughout the study.ResultsThe 90% confidence intervals for the ratios of geometric means, in the presence vs. absence of OLZ/SAM, were within the equivalence interval of 80–125% for both maximum plasma concentration and area under the plasma concentration–time curve over a 12-h dosing interval of lithium and of valproate. The safety profiles of lithium or valproate co-administered with OLZ/SAM were consistent with what has been previously reported for lithium or valproate. The safety profile of OLZ/SAM was consistent with that observed in previous clinical studies with OLZ/SAM.ConclusionsConsistent with previously reported findings on olanzapine, administration of multiple doses of OLZ/SAM did not have a clinically significant effect on the pharmacokinetics of lithium or valproate. Co-administration of OLZ/SAM and lithium or valproate was generally well tolerated; the safety profile of OLZ/SAM was consistent with that observed in previous clinical studies.

A novel and nonderivatization method for the determination of valproic acid in human serum by two-dimensional liquid chromatography.

A novel and robust two-dimensional liquid chromatography with ultraviolet detection method (2D-LC-UV) was developed and validated for high-throughput determination of the concentrations of valproic acid (VPA) in human plasma. This 2D-LC system was composed of a first-dimensional LC column, a second-dimensional LC column and an intermediate transfer column. The sample was directly injected into the 2D-LC system after an easy protein precipitation treatment. After online preconcentration and primary separation by the first-dimensional column, the target was captured by an intermediate column and then transferred to second-dimensional column for analysis. The system transferred the target through "central cutting" mode whereby the drug peak was not subject to interference from the matrix. The analysis cycle time was completed within 7.0 min. Compared with other methods that have been developed, the analysis time was reduced and the operation was much easier without any derivatization. The calibration curve was linear over the 5.90-188.94 μg/ml range for the VPA concentrations. The intra-day and inter-day precisions were <5.6%. The recoveries were in the range from 95.2 to 98.0%. This method appears to be sensitive, precise, rapid and low-cost for the quantification of VPA in serum sample.

The scientific and practical substantiation of the therapeutic drug monitoring procedure: validation of the analytical method of valproic acid measurement

The need for careful therapeutic drug monitoring (TDM) arises for measurement of drugs with a narrow therapeutic index (NTIDs), as well as for assuring their safe and controlled replacement with generics. In particular, this category includes anti-epileptic drugs, which use is associated with the range of issues during the management of therapy effectiveness and safety. One of these examples is valproic acid, which therapeutic concentrations vary greatly depending on the individual patient. The need to substantiate the choice and control of individual optimal dosing regimen of drugs, as well as to provide the rational use of generic NTIDs, determines the relevance of the introduction of TLM in the routine practice of standardized medical care for certain categories of patients, and it requires appropriate scientific and practical justification.Aim. To provide the scientific and practical substantiation of the procedure of TDM by validation of the laboratory method for determining the concentration of valproic acid in the blood plasma.Materials and methods. Analytical, statistical and biological methods were used in the study. Measurement of valproic acid concentration in a standardized sample of the blood plasma was performed by the photometric method using reagents produced by SIEMENS, Inc., USA and the control serum “Chemical control, level1” produced by Bio-Rad, Inc., USA. Measurements were made by a Siemens Bio Dimension RxL Max automatic biochemical analyzer.Results. The limits of intra-laboratory reproducibility by the factor of the laboratory assistant have been estimated as R = 3.25. The assessment of the repeatability and reproducibility of the method by the time factor and in different concentration ranges has shown the absence of gross errors and statistically significant differences in the measurements. It has been found that in the range of 73.8 ± 110 µg/ml valproic acid concentration values determined by this method using the Siemens Dimension RxL Max device can be considered accurate and reliable. The linearity of this method within the range of the concentrations measured has been also proven; it confirms the possibility of its use for measuring the concentration of valproic acid in the blood plasma.Conclusions. The scientific and practical substantiation obtained is necessary for the proper implementation of TDM in the process of providing medical care to particular categories of patients to optimize the individual dosing regimen of NTIDs. In addition, validation of the TDM method allows using it for assuring the safe and controlled generic replacement of NTIDs. The results of the work can be used in the process of further improvement and development of new analytical methods for TDM of valproic acid, as well as other NTIDs.

Evaluating the Differential Effects of Valproic Acid on Wharton's Jelly Mesenchymal Stem Cells.

Purpose: The histone deacetylases (HDAC) inhibitor, valproic acid (VPA), is a common antiepileptic drug and is attractive for its broad range of therapeutic effects on many diseases. It has been employed as an inducer of pluripotency in some cultured cells. Conversely, VPA has also been employed as an inducer of in vitro differentiation in many other cells. Therefore, we employed WJMSCs as a cellular target to evaluate the differential effects of of VPA on potency state and differentiation level of Wharton’s Jelly mesenchymal stem cells (WJMSCs) in various concentrations and different culture mediums. Methods: The isolated WJMSCs were cultured in DMEM (MSC medium). According to previous protocols, WJMSCs were treated with 0, 0.5 and 1 mM VPA in MSC or embryonic stem cell (ESC) medium and 2 mM VPA in neural differentiation medium. Real-time polymerase chain reaction (PCR) and western blot analysis were performed for evaluating the expression of pluripotency markers. MTT and caspase assays were also performed on VPA-treated cells. Results: The expression of pluripotency markers and the viability of the WJMSCs – determined by MTT assay – were significantly increased after 0.5 mM VPA treatment in ESC medium. A 2 mM VPA treatment in neural differentiation medium significantly diminished the expression of pluripotency markers and the viability of WJMSCs. Conclusion: According to our results, both VPA concentration and the medium context can influence VPA effects on WJMSCs. The differential effects of VPA on WJMSCs can reflect its wide range of effects in the treatment of various diseases.

Association of valproic acid and 2-propyl-4-pentenoic acid concentrations with adverse reaction in 254 Chinese patients with epilepsy.

To investigate the correlation of the concentrations of valproic acid (VPA) and 2-propyl-4-pentenoic acid (4-ene-VPA) with their adverse reactions, and to guide the clinical safety and rational use of VPA. Methods: We collected 254 epilepsy outpatients who took long-term use of sodium valproate oral solution single or combined with other antiepileptic drugs from Xiangya Hospital. The plasma concentrations of VPA and 4-ene-VPA in patients were determined by gas chromatography-mass spectrometry (GC-MS). The double variable correlation analysis was performed to analyze the effect of plasma 4-ene-VPA and VPA concentrations on adverse reactions. Results: The correlations between the PLT level and the dosage of VPA (P<0.01 and P<0.05, respectively), and the RBC level and the concentration of VPA (All P<0.01) were significant negatively. The concentrations of 4-ene-VPA, VPA, ALT, and AST in the polytherapy group were much higher than those in the monotherapy group (All P<0.05). In the monotherapy group, the ALT and AST levels in patients younger than or equal to 2 years old were significantly higher than those over 2 years old (P<0.001). In the polytherapy group, the levels of AST, WBC, and PLT in patients younger than or equal to 2 years old were higher than those over 2 years old (P<0.05). The levels of AST did not show positive correlation with the concentrations of 4-ene-VPA and VPA (r=0.031, r=0.035, all P>0.05), and the levels of ALT also did not show positive correlation with the concentrations of 4-ene-VPA and VPA (r=-0.064, r=-0.089, all P>0.05). Conclusion: VPA may affect blood routine indexes. Age and combination therapy with the non-enzyme-induced anti-epileptic drugs are risk factors for VPA-related liver dysfunctions and renal impairment. The determination of VPA and 4-ene VPA is not a suitable tool for early warning of the VPA-induced liver dysfunction.

Pharmacist impact on adherence of valproic acid therapy in pediatric patients with epilepsy using active education techniques

There is limited information on the impact of active education by a pharmacist in the population of pediatric patients with epilepsy (PWE) in China. The objective of this study was to assess the effect of education by pharmacists on medication adherence and percentage of valproic acid (VPA) samples reaching therapeutic reference range in these patients. This study was conducted at two teaching hospitals in Changsha, China. Patients were retrospectively identified from January 2016 to December 2017. Active education by a pharmacist in both oral and written formats was provided at the intervention hospital whereas standard passive pharmacist service (dispensing and answering questions) was provided at the control hospital. Medication adherence was assessed by the simplified medication adherence questionnaire (SMAQ), and serum concentrations of VPA were collected. The correlation between pharmacist education and medication adherence and percentage of VPA samples reaching therapeutic reference range were analyzed. A total of 2165 patients and 4343 serum VPA concentrations were included in the analysis. For the first therapeutic drug monitoring (TDM) measurement, there was no statistical difference between the two hospitals: 41.3% of VPA samples reached therapeutic range at the intervention hospital compared with 45.4% at the control hospital (χ2 = 3.686, P > 0.05). After pharmacist intervention at the intervention hospital, however, there were significant differences in the percentage of therapeutic VPA samples reaching therapeutic range between the first and the second, third, fourth, and fifth TDM measurements (χ2 = 9.756, P < 0.01; χ2 = 22.840, P < 0.01; χ2 = 15.816, P < 0.01; χ2 = 27.613, P < 0.01).Based on the SMAQ adherence assessment, adherence increased from a minimum of 56.0% to a maximum of 73.9% with stabilization during the last six months of follow-up at the intervention hospital. Both the medication adherence rate and the percentage of VPA samples reaching therapeutic range increased as the result of active education by a pharmacist, suggesting that continuous pharmacist intervention had a positive impact in outpatient pediatric PWE.

Valproic acid potently inhibits interictal-like epileptiform activity in prefrontal cortex pyramidal neurons

Valproic acid has a long-standing reputation of effectively treating the symptoms of not only epilepsy but also psychiatric conditions. In the latter, the exact mechanism by which valproate exerts its effect remains unclear. In this study, epileptiform bursts were recorded from pyramidal neurons in the prefrontal cortex (the brain region thought to be involved in psychiatric disorders) using the patch-clamp technique. An extracellular solution with no magnesium ions and elevated potassium levels that is known to induce epileptiform activity in vitro was used. Because of their short durations, the epileptiform bursts were regarded as interictal-like epileptiform activity, which is believed to be involved in cognitive impairment. Interictal discharges occur in many neuropsychiatric disorders as well as in healthy population.Epileptic activity in prefrontal cortex pyramidal neurons was potently inhibited by two therapeutic concentrations of valproic acid (20 μM and 200 μM). Moreover, valproate suppressed spontaneous excitatory postsynaptic potentials. Epileptiform bursts were fully inhibited by NMDA receptor antagonist, which suggests that epileptiform activity is driven by NMDA receptors. The inhibition of excitability in prefrontal cortex pyramidal neurons by valproate was also shown.This study shows that it is possible to evoke NMDA-dependent epileptiform activity in prefrontal cortex pyramidal neurons in vitro.We suggest that the prefrontal cortex is a good region for studying the influence of drugs on interictal epileptiform activity.

Effect of valproic acid on cisplatin-resistant ovarian cancer cell lines

Background and aims: Platinum resistance has been one of the most important problems in the management of ovarian cancer. The effects of various chemotherapeutic agents are limited in patients with platinum resistance. Therefore, developing new anticancer drugs that can improve the effect of currently used cytostatics is critical. The current study investigated the effects of valproic acid (VPA) alone and in combination with cisplatin on ovarian cancer cells. Methods: In this experimental study, the human ovarian cancer cell lines (A2780-S and A2780-CP) were grown in RPMI-1640 medium in appropriate culture conditions. The cells were treated with various concentrations of cisplatin (0.15-400 µg/mL) or VPA (10-2000 µg/mL) and were incubated for 24, 48, and 72 hours. Moreover, A2780 cells were co-treated with different concentrations of cisplatin and VPA for 48 hours. Afterward, cell viability was investigated using MTT assay. GraphPad Prism statistical software was used for the data analysis and ANOVA and Duncan’s test were conducted. Results: A dose- and time-dependent reduction was observed in cell viability following the treatment with cisplatin or VPA. Moreover, cotreatment of the A2780 cells with cisplatin and VPA resulted in a significantly greater inhibition of cell viability compared to the treatment with either agent alone. Conclusion: Overall, it can be argued that VPA does not only cause inhibition of proliferation and induction of apoptosis in ovarian cancer cells but also helps to enhance the antiproliferative effects of cisplatin and results in the increased susceptibility to cisplatin in resistant cells. VPA may therefore be used to treat cancer in the future.

Levocarnitine for the Treatment of Valproic Acid-Induced Hyperammonemic Encephalopathy in Children: The Experience of a Large, Tertiary Care Pediatric Hospital and a Poison Center.

Although rare, symptomatic hyperammonemia is sometimes associated with valproic acid (VPA), especially in children. L-carnitine (levocarnitine), sometimes classified as an essential amino acid, is vital to mitochondrial utilization of fatty acids and can be helpful in treating this condition. The data supporting this, however, are limited. The aim of the study was to illustrate the role of L-carnitine in the treatment of patients with VPA-induced hyperammonemic encephalopathy (VPE) at 2 different institutions. Medical records of affected patients were reviewed; data collected included exposure history, clinical manifestations, physical examination, and laboratory values. There were 13 cases of VPE; 12 were associated with therapeutic dosing and 1 with an overdose. The maximum ammonia concentration was 557 μmol/L, and blood concentrations of VPA ranged from 68 to 600 μg/mL (therapeutic range 50-100 μg/mL). In all cases, liver function tests were normal or only mildly increased. In this study, 12 patients received a daily dose of L-carnitine 100 mg/kg, and 1 received 200 mg/kg (intravenous infusion over 30 minutes) divided every 8 hours until clinical improvement. All patients made a full recovery. None developed adverse effects or reactions, and no cases of toxicity were reported. Our series suggests that intravenous L-carnitine, at a dose of 100 mg·kg·d in 3 divided doses each over 30 minutes until clinical improvement occurs, is a safe and effective treatment in the management of VPE in children.

Valproic acid concentrations in nursing mothers, mature milk, and breastfed infants in monotherapy and combination therapy

Valproic acid (VPA) is currently one of the four most often prescribed antiepileptic drugs (AEDs) in pregnancy. However, only a small number of studies have measured suckling infant serum levels of the drug. We studied the transport of VPA from breastfeeding mothers to the mature milk and breastfed infants and the influence of comedication with enzyme-inducing AEDs. The data of 30 nursing women treated by VPA were analyzed retrospectively. Mature milk, maternal, and infant serum levels were collected between the 6th and 32nd postnatal day and measured by gas chromatography during the years 1996–2017.Valproic acid levels varied from 5.4 to 69.0 mg/L (mean: 39.0 ± 16.1 mg/L) in the maternal serum, from <1.0 to 16.7 mg/L (mean: 1.6 ± 3.9 mg/L) in the milk, and from <1.0 to 17.5 mg/L (mean: 4.2 ± 4.3 mg/L) in the infant serum. The milk/maternal serum level ratio ranged from <0.03 to 0.25 (mean: 0.03 ± 0.06) and the infant/maternal serum level ratio from <0.03 to 0.61 (mean: 0.11 ± 0.13). Sixty-seven percent of milk and 33% of infant VPA concentrations were below the limit of quantification. No correlations were observed between maternal serum and milk levels or between maternal and infant serum levels. In conclusion, none of the milk or infant serum VPA levels reached the lower limit of the reference range used for the general population with epilepsy, so the degree of VPA exposure in breastfed infants is less than during gestation. Nevertheless, if signs of potential adverse reactions manifest, infant serum concentrations should be measured.

Valproic Acid Accelerates Neural Outgrowth during Dorsal Root Ganglia Neurogenesis In Vitro

Background: Valproic acid (VPA) is an anti-convulsant drug used to treat seizures and a variety of neural pathologies. Studies have shown that VPA exposure in rodent embryos leads to behavioral characteristics similar to those in humans with autism spectrum disorder (ASD). Utilizing this rodent model of ASD, research has led to a recognized mechanism of action of VPA involving brain overgrowth and hyperconnectivity, likely caused by epigenetic alteration of gene expression through inhibition of histone deacetylases.Objective: To gain further insight concerning this mechanism we modeled the development of neural connectivity at the cellular level.Method: We cultured dorsal root ganglia (DRGs) taken from eight-day old chick embryos in a range of VPA concentrations and investigated aspects of neuronal structure and behavior. DRGs were cultured 48 hours, fixed, and immunostained to reveal the locations of neural networks with synaptic vesicles.Results: We found a concentration-dependant relationship with a significant increase in neurite length in VPA concentrations of 1 and 2 mM, and the effect was still present though weaker at 4 and 6 mM. Trichostatin A (TSA), another histone deacetylase inhibitor, caused similar responses. To further characterize the effects, we carried out time-lapse imaging of growth cones of extending neurites. We found that VPA increased the area changing activity of growth cones, augmenting their exploratory capabilities, along with significantly enhancing overall advancement, thus increasing the ability to extend and form synapses. The average total of stained synaptic areas surrounding each cultured DRG was significantly increased in 6 mM VPA, but not significantly at the lower concentrations compared to controls.Conclusion: Our results show that VPA, at 1 mM and higher concentrations increases growth cone activity, and increases the number of neurites and their extension, a neurotrophic effect. It also increases synaptogenesis at 6 mM, supporting the theory of developmental neuronal overgrowth.

HDAC2 Inhibitor Valproic Acid Increases Radiation Sensitivity of Drug-Resistant Melanoma Cells.

Resistance to anticancer drugs limits the effectiveness of chemotherapy in cancers. Melanoma cell lines B16F10C and A375C (parental) and B16F10R and A375R (drug-resistant sublines) were used to test radiation sensitization potential of valproic acid (VPA), an inhibitor of Histone deacetylase2 (HDAC2) and LDN193189 (BMP inhibitor). Inhibitors of other signaling pathways were tested for cross-resistance with the resistant cell lines. Cells were pretreated with low concentrations of VPA/ LDN193189 and exposed to 2 Gy radiation for radiation sensitization experiments. Assays-3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT), live/dead, clonogenic, and melanin estimation were performed to test the effects of radiation sensitization. Interactions of VPA and HDAC2 were studied in silico. Dose-dependent growth inhibition was observed with all tested drugs. Radiation sensitization of melanoma cells with low dose of VPA induced synergistic cell death, decreased clonogenicity, and decreased melanin content. In silico docking showed two stable interactions between Arg39 of HDAC2 and VPA. In conclusion, pretreatment with low doses of VPA has a potential for sensitizing melanoma cells to low doses of radiation. The binding of VPA to HDAC2 reverses the drug resistance in melanoma and induces the cell death. Sensitization effects of VPA can be used for targeting drug-resistant cancers.

Enhancing the expression of neurotrophic factors in epidermal neural crest stem cells by valproic acid: A potential candidate for combinatorial treatment

Effective delivery of trophic factors to cure neurological disorders and traumatic injuries is a major challenge. With promising therapeutic effects of epidermal neural crest stem cells (EPI-NCSCs) in preclinical spinal cord injury, there is an implication that these stem cells might provide supportive role through releasing various trophic agents. Hence, the present study was designed to assess the influence of valproic acid (VPA), a well-known histone deacetylases inhibitor, on mRNA expression of selected trophic factors. In this study, following stem cell migration from explanted hair bulges, immunostaining against Nestin, SOX-10, DCX, β-III tubulin and GFAP was carried out. Then, cells were treated with various clinically relevant concentrations of VPA and the survival rate was defined by MTT assay. Finally, stem cells were treated with 0.1 and 1 mM VPA and the drug impact on the transcription level of BDNF, GDNF, VEGF, NGF and NT3 at 6, 24, 72, 168 h was assessed by quantitative real-time PCR. The examined proteins expressions in the population of migrated cells confirmed the identity of stem cells as EPI-NCSCs. In addition, MTT assay showed that all three tested concentrations of VPA were suitable to treat these cells. Trophic factors assessment, following treatment revealed the mRNA expression level of BDNF, GDNF and VEGF could be significantly up- regulated at various time points, mainly by 1 mM VPA. However, NGF and NT3 transcripts were enhanced at few limited time points. Our findings showed that EPI-NCSCs due to secretion of various trophic factors are potential candidate to deliver the required trophic agents and their potential can be enhanced by 1 mM VPA, predominantly following 168 h treatment. Hence, these cells can be utilized to modulate destructive context of neurological disorders and injuries.

A meta-analysis of the influence of UGT1A6 genetic polymorphisms on valproic acid pharmacokinetics .

Genetic polymorphisms in UGT1A6 might contribute to interindividual variability in the pharmacokinetics of valproic acid (VPA). However, whether the 541A>G and 552A>C variants decrease VPA concentration remains controversial. Herein, we performed a meta-analysis to evaluate the influence of UGT1A6 genetic polymorphisms on VPA pharmacokinetics. Searches, two-step selection, data extraction, and quality assessment were performed using a conventional protocol, and the influence of UGT1A6 genetic polymorphisms on concentration-to-dose ratio was quantitatively assessed by pooled analysis using the Comprehensive Meta-Analysis program. Six studies using monotherapy were included in the quantitative analysis. Concentration-to-dose ratio of 541A>G and 552A>C homozygous variant were significantly lower than that of the wild-type (WT; standardized difference in means (SDM) = -0.771, 95% confidence interval (CI) = -1.123 to -0.419; SDM = -0.879, 95% CI = -1.257 to -0.500, respectively). Differences were also significant in both child and adult subgroups analysis. For heterozygous variants, there was no significant difference in concentration-to-dose ratio between 541A>G and 552A>C heterozygous variant and WT (SDM = -0.183, 95% CI = -0.449 to 0.084; SDM = -0.275, 95% CI = -0.647 to 0.097, respectively). In conclusion, concentration-to-dose ratio for VPA monotherapy were significantly lower for UGT1A6 homozygous variants 541A>G and 552A>C than for the WT. .

Effect of Lithium and Valproate on Proliferation and Migration of Limbal Epithelial Stem/Progenitor Cells

ABSTRACTPurpose: The effects of lithium (Li) and Valproic Acid (VA) drugs have been recently revealed to improve the Mesenchymal stem cells’)MSCs (migration and proliferation processes. The aim of this study is to determine the expression of the genes involved in the proliferation and migration of limbal epithelial stem/progenitor cells (LESPCs) after treatment with Li and VA.Methods: After extraction of LSCs from human Corneoscleral tissue, cells were subcultured three times. The cell culture media were divided into four separate groups including groups treated with VA, Li, combination, and control groups after determining the non-toxic concentration of drugs (64mml) Li and (28mml) VA based on MTT assay, and then cells cultures were treated for 3 hours. A real-time polymerase chain reaction was performed to detect the expression levels of CD44, Ki67, CXCR4, CXCR7, MMP-2, MMP-9, and SDF-1 genes. Changes in the expression of each gene in different treatments were calculated. Finally, the graphs were analyzed by SPSS (Version 18) software.Results: The highest expression of CXCR4 and CXCR7 was in the Li-treated group. Additionally, the highest expression levels of MMP-9 and CD44 genes were observed in the VA-treated group. In contrast, the expression level of SDF-1a, MMP2, and Ki67 genes in all three treatment groups reduced compared to the control group.Conclusion: Increasing the LSCs migration genes (CXCR4 and MMP9) was more evident than cell proliferation genes (Ki67). In sum, Li and VA can affect the process of proliferation and migration of LSCs in vitro.