Vinpocetine, cognition, and epilepsy

Challenges and directions in epilepsy diagnostics and therapeutics: Proceedings of the 17th Epilepsy Therapies and Diagnostics Development conference

Substantial efforts are underway toward optimizing the diagnosis, monitoring, and treatment of seizures and epilepsy. We describe preclinical programs in place for screening investigational therapeutic candidates in animal models, with particular attention to identifying and eliminating drugs that might paradoxically aggravate seizure burden. After preclinical development, we discuss challenges and solutions in the design and regulatory logistics of clinical trial execution, and efforts to develop disease biomarkers and interventions that may be not only seizure-suppressing, but also disease-modifying. As disease-modifying treatments are designed, there is clear recognition that, although seizures represent one critical therapeutic target, targeting nonseizure outcomes like cognitive development or functional outcomes requires changes to traditional designs. This reflects our increasing understanding that epilepsy is a disease with profound impact on quality of life for the patient and caregivers due to both seizures themselves and other nonseizure factors. This review examines selected key challenges and future directions in epilepsy diagnostics and therapeutics, from drug discovery to translational application.

Synthesis and pharmacological activity of vinpocetine derivatives

Vinpocetine and its derivatives were extensively employed in the treatment of ischemic stroke, serving as effective cerebrovascular vasodilators. They could also be utilized for neuroprotection, anti-inflammatory purposes, anti-aging interventions, insomnia treatment, and antidepressant effects. However, due to issues such as hepatic first-pass effect, low bioavailability, and poor patient compliance with multiple dosing, the secondary development of Vinpocetine to address these limitations became a prominent area of research. Five primary methodologies were employed for the synthesis of Vinpocetine derivatives. These included substitution on the A ring to modify the 14-ester group, alteration of the 16-ethyl group, simplification of the D and E rings, and modification of the conformation of Vinpocetine. This paper summarized the current synthesis and activity studies of Vinpocetine and its derivatives, with the aim of providing a reference for the discovery of more potent derivatives of Vinpocetine.

Antidepressant-like Effect of the Eburnamine-Type Molecule Vindeburnol in Rat and Mouse Models of Ultrasound-Induced Depression

Vindeburnol (VIND, RU24722, BC19), a synthetic molecule derived from the eburnamine-vincamine alkaloid group, has many neuropsychopharmacological effects, but its antidepressant-like effects are poorly understood and have only been described in a few patents. To reliably estimate this effect, vindeburnol was studied in a model of long-term variable-frequency ultrasound (US) exposure at 20-45 kHz in male Wistar rats and BALB/c mice. Vindeburnol was administered chronically for 21 days against a background of simultaneous ultrasound exposure at a dose of 20 mg/kg intraperitoneally (IP). Using four behavioral tests, the sucrose preference test (SPT), the social interaction test (SIT), the open field test (OFT), and the forced swimming test (FST), we found that the treatment with the compound diminished depression-like symptoms in mice and rats. The compound restored the ultrasound-related reduced sucrose consumption to control levels and increased social interaction time in mice and rats compared with those in ultrasound-exposed animals. Vindeburnol showed contraversive results of horizontal and vertical activity in both species and generally did not increase locomotor activity. At the same time, the compound showed a specific effect in the FST, significantly reducing the immobility time. Moreover, we found an increase in norepinephrine, dopamine, and its metabolite levels in the brainstem, as well as an increase in dopamine, 3-methoxytyramine, and 3,4-dihydroxyphenylacetic acid levels in the striatum. We also observed a statistically significant increase in tyrosine hydroxylase (TH) levels in the region containing the locus coeruleus (LC). We suggest that using its distinct chemical structure and pharmacological activity as a starting point could boost antidepressant drug discovery.

Development and optimization of in-situ gel containing chitosan nanoparticles for possible nose-to-brain delivery of vinpocetine

Vinpocetine (VIN), a derivative of vincamine found in the vinca plant, widens blood vessels in the brain and has been shown to improve cognitive function, memory, and cerebrovascular disorders. Nevertheless, the clinical utility of VIN is constrained by factors such as low oral bioavailability owing to the first-pass metabolism that often demands frequent dosing of 3-4 tablets/day. In this regard, the present work aimed to develop VIN-loaded chitosan nanoparticles (VIN-CH-NPs) to surmount these limitations and in view to enhance delivery to the brain of VIN by minimizing systemic exposure. The chitosan (CH) nanoparticles (NP) were developed by ionotropic gelation technique employing tripolyphosphate (TPP) as a cross-linking agent. Employing Design of Experiments (DoE), the effect of CH and TPP concentrations and stirring speed were systematically optimized using Box Behnken design (BBD). The optimized batch of nanoparticles displayed a particle size, zeta potential, entrapment efficiency, and drug loading of 130.6 ± 8.38 nm, +40.81 ± 0.11 mV, 97.56 ± 0.04 %, and 61 ± 0.89 %, respectively. Fourier Transform Infrared Spectroscopy indicated the chemical integrity of the drug ruling out the interaction between the VIN and excipients used. DSC and PXRD data indicated that reduction of the crystallinity of VIN in the chitosan matrix. These VIN-CH-NPs manifested good stability, exhibiting an almost spherical morphology. To mitigate rapid mucociliary clearance upon intranasal administration, the optimized VIN-CH-NPs were incorporated into thermosensitive in situ gel (VIN-CHN-ISG). It was observed that the in-situ gel loaded with nanoparticles was opalescent with a pH level of 5.3 ± 0.38. It was also noted that the gelation temperature was 32 ± 0.89 °C, and the gelation time was approximately 15 s. The drug delivery to the brain through the nasal application of optimized VIN-NPs in situ gel was assessed in rats. The results indicated significant nasal application of the in-situ gel nearly doubled the Cmax (P < 0.05) and AUC0-t (P < 0.05) in the brain compared to oral administration. Nasal administration improved drug delivery to the brain by reducing systemic exposure to VIN. A histopathological study of the nasal mucosa revealed no irritation or toxicity, making it safe for nasal administration. These findings suggest that the developed NPs in-situ gel effectively targeted vinpocetine to the brain through the nasal pathway, providing a potential therapeutic strategy for managing Alzheimer's disease.

An integrated in vitro human iPSCs-derived neuron and in vivo animal approach for preclinical screening of anti-seizure compounds

INTRODUCTION

One-third of people with epilepsy continue to experience seizures despite treatment with existing anti-seizure medications (ASMs). The failure of modern ASMs to substantially improve epilepsy prognosis has been partly attributed to overreliance on acute rodent models in preclinical drug development as they do not adequately recapitulate the mechanisms of human epilepsy, are labor-intensive and unsuitable for high-throughput screening (HTS). There is an urgent need to find human-relevant HTS models in preclinical drug development to identify novel anti-seizure compounds.

OBJECTIVES

This paper developed high-throughput preclinical screening models to identify new ASMs.

METHODS

14 natural compounds (α-asarone, curcumin, vinpocetine, magnolol, ligustrazine, osthole, tanshinone IIA, piperine, gastrodin, quercetin, berberine, chrysin, schizandrin A and resveratrol) were assessed for their ability to suppress epileptiform activity as measured by multi-electrode arrays (MEA) in neural cultures derived from human induced pluripotent stem cells (iPSCs). In parallel, they were tested for anti-seizure effects in zebrafish and mouse models, which have been widely used in development of modern ASMs. The effects of the compounds in these models were compared. Two approved ASMs were used as positive controls.

RESULTS

Epileptiform activity could be induced in iPSCs-derived neurons following treatment with 4-aminopyridine (4-AP) and inhibited by standard ASMs, carbamazepine, and phenytoin. Eight of the 14 natural compounds significantly inhibited the epileptiform activity in iPSCs-derived neurons. Among them, piperine, magnolol, α-asarone, and osthole showed significant anti-seizure effects both in zebrafish and mice. Comparative analysis showed that compounds ineffective in the iPSCs-derived neural model also showed no anti-seizure effects in the zebrafish or mouse models.

CONCLUSION

Our findings support the use of iPSCs-derived human neurons for first-line high-throughput screening to identify compounds with anti-seizure properties and exclude ineffective compounds. Effective compounds may then be selected for animal evaluation before clinical testing. This integrated approach may improve the efficiency of developing novel ASMs.

Clinical Pharmacology of Vinpocetine: Properties Revisited and Introduction of a Population Pharmacokinetic Model for Its Metabolite, Apovincaminic Acid (AVA)

This paper examines the use of vinpocetine in the context of clinical pharmacology. The main and active metabolite of vinpocetine is apovincaminic acid (AVA). Due to the scarce information in the literature on AVA pharmacokinetics, we propose a population pharmacokinetic (PopPK) model for AVA based on a study in healthy volunteers with three different formulations of vinpocetine. The suggested PopPK model (and simulations) could be helpful in ensuring the more effective and safer use of the vinpocetine in the future given the increasing range of suggested indications for its use.

Vinpocetine improved neuropsychiatric and epileptic outcomes in a patient with a GABRA1 loss-of-function variant

Vinpocetine is a synthetic derivative of the alkaloid vincamine and has been used as a dietary supplement for decades. Following a positive report of the use of vinpocetine in a patient with a loss-of-function GABRB3 variant, we here describe another patient with a loss-of-function GABRA1 variant (p.(Arg112Gln)) who benefited from vinpocetine treatment. This patient was diagnosed with autism spectrum disorder, psychiatric complications, and therapy-resistant focal epilepsy. Upon add-on treatment with 40 mg vinpocetine daily for 16 months, the patient experienced an overall improved quality of life as well as seizure freedom. Our findings corroborate that vinpocetine can attenuate epilepsy-associated behavioral issues in patients with loss-of-function GABAA receptor gene variants.

New insights on the potential effect of vinpocetine in Parkinson's disease: one of the neglected warden and baffling topics

Vinpocetine (VPN) is an ethyl apovincaminate that has anti-inflammatory and antioxidant effects by inhibiting the expression of nuclear factor kappa B (NF-κB) and phosphodiesterase enzyme 1 (PDE-1). VPN is used in the management of stroke, dementia, and other neurodegenerative brain diseases. VPN may be effective in treating Parkinson's disease (PD). Therefore, this review aimed to clarify the mechanistic role of VPN in the management of PD. VPN has protective and restorative effects against neuronal injury by reducing neuroinflammation, and improvement of synaptic plasticity and cerebral blood flow. VPN protects dopaminergic neurons by reducing oxidative stress, lipid peroxidation, glutamate neurotoxicity, and regulation of Ca+ 2 overloads. VPN can alleviate PD neuropathology through its anti-inflammatory, antioxidant, antiapoptotic and neurogenic effects. VPN through inhibition of PDE1 improves cyclic adenosine monophosphate (cAMP)/cyclic guanosine monophosphate (cGMP) signaling in the dopaminergic neurons of the substantia nigra (SN). VPN improves PD neuropathology through PDE1 inhibition with a subsequent increase of the cAMP/cGMP signaling pathway. Therefore, increasing cAMP leads to antioxidant effects, while augmentation of cGMP by VPN leads to anti-inflammatory effects which reduced neurotoxicity and development of motor severity in PD. In conclusion, this review indicated that VPN could be effective in the management of PD.