Analysis of GABRB3 gene mRNA expression and motor coordination after administration of valerian extracts (Valeriana officinalis) in BALB/c mice

Abstract

Background: Valeriana officinalis has often been used to treat sleep disorders as a traditional medicine for 2000 years. The sedative effect of valerian extract is facilitated by the GABA A receptor β3 subunit. The aim of this study is to determine the effect of valerian extract on GABRB3 gene mRNA expression and sedative effect in BALB/c mice. Methods: This is an experimental preclinical study using a posttest-only control group design. A total of 20 BALB/c mice were randomly allocated into four groups consisting of five mice each. Group I was given 5 ml of Aqua Dest (distilled water), group II was given 0.025 mg/10 g of diazepam, group III was given 2.5 mg/10 g of valerian extract, and group IV was given 5 mg/10 g of valerian extract. The drugs were administrated for seven days through a gastric gavage. The rotarod test was performed on the seventh day. A blood sample was taken on the first day before drug administration and after the rotarod test on the seventh day to be analyzed using quantitative real-time PCR. Results: GABRB3 gene mRNA expression showed a significant increase in groups II, III, and IV (p <0.0001). There was significant difference between group III and IV. The examination of motor coordination (rotarod test) showed a significant difference (p <0.05) between group I and group II, between group I and group III, and between group I and group IV. There was no significant difference between group II and both groups III and IV. Conclusions: GABRB3 gene mRNA expression was significantly increased after the administration of valerian extract. Based on the rotarod test, valerian extract and diazepam had a clinically similar sedation effect. A higher dose of valerian extract does not yield a higher level of GABRB3 gene mRNA expression nor sedative effects.