Association Between Electron-Shuttling Capacity and Neuroprotective Potential of Huang-Lian-Jie-Du-Tang: A Bioelectrochemical, Biochemical and Computational Study

Abstract

Introduction Although the neuroprotective properties of Huang-Lian-Jie-Du-Tang (HLJDT) are well-documented, its specific redox mechanisms and capacity for mediating electron transfer remain poorly characterized. In this study, a combination of bioelectrochemical analysis using Microbial Fuel Cells (MFCs), biochemical assays, and computational docking data was used to analyze the correlation between the electron-shuttling capability of HLJDT and its in vitro neuroprotective effects.Methods FRAP and DPPH activities were also determined to complement the quantification of the antioxidant potential and phytochemical content of HLJDT by total polyphenol, flavonoid, and condensed tannin assays. Electron-shuttling capacity and power density were measured using bioelectrochemical profiling with MFCs. The assessed neuroprotective potential was done through an in vitro acetylcholinesterase (AChE) inhibitory assay. Molecular docking of HLJDT compounds and in silico network pharmacology were performed to determine their interactions with neuroprotective targets.Results Phytochemical analysis indicated that ethanolic extracts, especially the traditional 3:2:2:3 formulation (HLJDT-B-E), were richest in flavonoids and condensed tannins, which were associated with high antioxidant activity (DPPH IC50 = 0.635 +/- 0.008 mg/mL; FRAP = 127.237 +/- 0.762 mg Trolox equivalent/g crude extract). The electron-shuttling capacity in MFCs was also highest in HLJDT-B-E, which produced the highest power density of 18.0662 +/- 2.1622 mW/m2. The extract showed potent in vitro AChE inhibition (IC50 = 0.014 +/- 0.0003 mg/mL), which was lower than that of the reference drug galantamine, in this set-up. Multitarget agent baicalin was discovered in molecular docking with high binding affinity towards the proteins associated with Parkinson's disease, such as MAO-B, which indicates a possible polypharmacological explanation for its actions.Discussion The results indicate a potential association between HLJDT's neuroprotective capacity and a synergistic effect of its antioxidant, electron-shuttling, and enzyme-inhibitory properties. The correlation between power density, antioxidant potency, and AChE inhibition suggests that electron-shuttling could be a redox-based process that alleviates oxidative stress via alternative pathways beyond direct radical scavenging.Conclusion The data reveal a correlative relationship between the electron-shuttling property of HLJDT and its neuroprotective effects in vitro. This bioelectrochemical and pharmacological compound model positions HLJDT as a highly promising multitarget therapeutic candidate and suggests electron-transfer capacity as a useful, novel index for characterizing neuroprotective natural products. Although the results offer a combined redox-based framework, neuroprotective effects were concluded based on in vitro and in silico models; direct validation in cellular or neuronal systems is required before any neuroprotective claims can be substantiated.