In vitro studies to investigate the potential neuroprotective and neurotransmitter modulation effects of a standardized Ginkgo biloba extract associated with phosphatidylserine

Mehtap Kara^1*Gozde Hasbal-Celikok¹M Pilar Gómez-Serranillos²Marta Sánchez²Claudia Owsianik²Tugba Yilmaz-Ozden¹Ezgi Öztas¹Nazli Arda¹Merve Tunc¹Cigdem Sevim³Giovanna Petrangolini^4*Fazle Rabbani^5*Ikram Ujjan^6*Amjad Khan⁶

• ¹Istanbul University, Istanbul, Türkiye
• ²Universidad Complutense de Madrid, Madrid, Spain
• ³Kastamonu Universitesi, Kastamonu, Türkiye
• ⁴Indena SpA, Milan, Italy
• ⁵Lady Reading Hospital, Peshawar, Pakistan
• ⁶Liaquat University of Medical & Health Sciences, Jamshoro, Pakistan

Cognitive impairment and mood disturbances are increasingly linked to underlying mechanisms such as oxidative stress, neurotransmitter dysregulation, and reduced neurotrophic support. As conventional pharmacological treatments often provide limited efficacy or are associated with tolerability concerns, there is growing scientific interest in botanical supporting tools that may modulate the above pathways and provide complementary support for cognitive function and emotional well-being. This study aimed to investigate the mechanistic basis of a botanical association consisting of standardized Ginkgo biloba extract (GBE) from leaves and phosphatidylserine (PS) (combined referred as GBP) (Virtiva™ Plus), focusing on its potential effects on neurotransmitter-related enzymes and receptors, neuroprotection under oxidative stress, neurotrophic signaling, and antioxidant capacity. GBP was characterized analytically and evaluated in a series of validated in vitro assays using human SH-SY5Y neuroblastoma cells and multiple cell-free antioxidant systems. Neurotransmitter effect assays demonstrated that GBP inhibited acetylcholinesterase (AChE) and monoamine oxidase-A (MAO-A) in a concentration-dependent manner, suggesting selective modulation of cholinergic and monoaminergic pathways relevant to cognition and mood regulation. Enzyme modulation observed at micromolar concentrations supports mechanistic plausibility of Ginkgo biloba constituents in neurochemical pathways rather than direct modeling of physiological exposure. In SH-SY5Y cells exposed to hydrogen peroxide (H₂O₂), GBP improved cell viability, confirming no intrinsic cytotoxicity, and reduced lactate dehydrogenase release, indicating protection against oxidative stress–induced cytotoxicity. GBP also partially restored brain-derived neurotrophic factor (BDNF) levels in SH-SY5Y cells suppressed by H₂O₂, supporting preservation of neurotrophic signaling linked to neuronal survival and synaptic plasticity. In cell-free antioxidant assays, GBP demonstrated broad-spectrum activity across 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), Ferric Reducing Antioxidant Power (FRAP), Oxygen radical absorbance capacity (ORAC), Hydroxyl Radical Antioxidant Capacity (HORAC), Total Phenolic Content (TPC), and Total Antioxidant Status (TAS) assays, validating its capacity to neutralize free radicals and support redox balance. Collectively, these findings provide mechanistic evidence supporting the biological plausibility of multitarget actions of GBP, including neurotransmitter modulation, antioxidant effects, neuroprotection, and preservation of neurotrophic signaling, which may help explain previously reported cognitive-and mood-related outcomes.