Page 36 - Q. Neuroscience

[Q. Neuroscience-20]

Inhibitory effect of carvacrol on lipopolysaccharide-induced

memory impairment in rats

INSOP SHIM²˙³, HYEJUNG LEE¹˙³, DAE-HYUN HAHM²˙³, BOMBI LEE¹

¹Acupuncture and Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul

02447, Republic of Korea, ²Department of Physiology, College of Medicine, Kyung Hee University, Seoul 02447,
Republic of Korea, ³The Graduate School of Basic Science of Korean Medicine, College of Korean Medicine, Kyung

Hee University, Seoul 02447, Republic of Korea

Neuroinflammation is an important process underlying a wide variety of neurodegenerative diseases. Carvacrol

(CAR) is a phenolic monoterpene commonly used as a food additive due to its antibacterial properties, but it has
also been shown to exhibit strong antioxidative, anti-inflammatory, and neuroprotective effects. Here, we sought to
investigate the effects of CAR on inflammation in the hippocampus and prefrontal cortex, as well as the molecular

mechanisms underlying these effects. In our study, lipopolysaccharide was injected into the lateral ventricle of rats
to induce memory impairment and neuroinflammation. Daily administration of CAR for 21 days improved

recognition, discrimination, and memory impairments relative to untreated controls. CAR administration significantly
attenuated expression of several inflammatory factors in the brain, including interleukin-1β, tumor necrosis factor-

α, and cyclooxygenase-2. In addition, CAR significantly increased expression of BDNF mRNA, and decreased
expression of TLR4 mRNA. Taken together, these results show that CAR can improve memory impairment caused

by neuroinflammation. This cognitive enhancement is due to the anti-inflammatory effects of CAR CAR medicated
by its regulation of BDNF and TLR4.