Kaempferia galanga L. Extract Administration Attenuate Aquaporin-4 Expression in Traumatic Brain Injury: An Experimental Study in Rats

Introduction: Traumatic brain injury (TBI) is still a major health problem in the world. It might cause long-term disability that affect socio-economic life and become nation health burden. Post-traumatic cerebral edema might develop and commit to an unfavorable prognosis. Aquaporin 4 (AQP4) is water channel protein and a key regulator of water metabolism in the brain. Although the mechanism of AQP4 in the regulation of post-traumatic brain edema remains controversial, AQP4-lacking mice show better survival and decreased brain edema. Thus, novel strategies that suppress AQP4 become a potential field. We hypothesized that Kaempferia galanga L. may suppress brain expression of AQP4 following TBI and possibly limit the development of cerebral edema due to its neuroinflammation properties. Method: We conducted TBI to experimental rats, then given Kaempferia galanga L. extract at a dose of 600 mg/kg BW and 1200 mg/kg BW. Evaluation intensity of AQP4 expression by immunohistochemistry was performed 24 and 48 hours later to see its therapeutic effect. Results: Administration of Kaempferia galanga L. extract at a dose of 1200 mg/kg BW showed weak expression of AQP4 in all samples, both 24 and 48 hours following traumatic brain injury treatment. Conclusions: Intensity of AQP4 expression in rats' brain was lower at 24 and 48 hours after TBI in rats receiving Kaempferia galanga L. extract with dose 1200 mg/ kg BW compared to the other groups. Our result indicates that Kaempferia galanga L. might affect the expression of brain AQP4 in a dose-dependent manner.