22 - Combining Electroacupuncture and Metformin Therapy to Enhance Neural Recovery and Alleviate Cognitive Impairment After Traumatic Brain Injury

Poster Board Number: 22
There are separate poster presentation times for odd and even posters.
Odd poster #s – first hour
Even poster #s – second hour

Co-authors:

Wu Di - Anatomy - Harbin Medical University; Sun Liang - Associate Professor, Anatomy, Harbin Medical University; Wu Shuliang - Professor, Anatomy, Harbin Medical College; Yafang Zhang - Professor, Anatomy, Harbin Medical University

Abstract Body : Traumatic brain injury (TBI) is a global crisis, impacting adult well-being and cognition. Current interventions fall short in fully restoring the central nervous system post-TBI, necessitating urgent treatments. Electroacupuncture, combining low-frequency pulses with traditional Chinese acupuncture, and metformin, a type-2 diabetes medication, show promise in mitigating neural damage post-TBI. This study explores their collaborative effect on cognitive recovery, myelin regeneration, synaptogenesis, neurogenesis, and microglial suppression.

C57BL/6 male mice were segregated into control, TBI, TBI+E (electroacupuncture), TBI+M (metformin), and TBI+E+M groups. Novel object recognition tests revealed significantly heightened preference for novel objects in TBI+E and TBI+M mice compared to TBI counterparts with impaired visual memory; TBI+E+M mice recovered to levels similar to uninjured controls. Hematoxylin and eosin (HE) staining exposed tissue defects, a cortical cavity, and disordered cell structure in TBI mice. Immunofluorescence analyses indicated restored MBP-positive myelinated areas in TBI+E+M mice, suggesting partial myelin regeneration. TBI+E+M mice exhibited increased SYN-positive synaptic puncta fluorescence in the cortex and hippocampal CA3 region, with synapse formation reaching healthy control levels in the cortex.

TBI-induced neuroinflammatory IBA1-positive microglia increased, while TBI+E+M reversed microglial numbers to control levels. Western Blot revealed elevated Arg1 and p-AKT levels (M2 markers) in TBI+E+M, implying anti-inflammatory microglial polarization. TBI exhibited increased iNOS and p-ERK1/2 (M1 markers), reduced in TBI+E+M. Immunohistochemistry unveiled diminished SOX2-positive neural stem cells and NeuN-positive mature neurons in TBI mice; TBI+E+M restored these, suggesting enhanced neurogenesis. NeuN-positive mature neuron density in SGZ rebounded to control levels in TBI+E+M, indicating substantial recovery.

Combining Electroacupuncture with metformin post-TBI enhances cognitive recovery, promotes myelin and synapse regeneration, and reduces inflammation, providing neuroprotection. This synergistic approach modulates key markers, effectively suppressing secondary inflammation and fostering adult hippocampal neurogenesis-a promising strategy for treating traumatic brain injury.