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 GABAA 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.