A mechanistic evaluation of the traditional uses of Nepeta ruderalis in gastrointestinal and airway disorders

Abstract

Context: Nepeta ruderalis Buch.-Ham. (Lamiaceae), locally known as Badranj Boya, is an aromatic herb used traditionally as an antispasmodic, antidiarrhoeal, and anti-asthamatic remedy.

Objective: Aqueous methanolic extract of N. ruderalis was studied to investigate its traditional uses.

Materials and methods: Study was conducted from September 2015 to February 2016. In vitro spasmolytic and broncho-relaxant activity of crude extract of N. ruderalis (whole plant) was evaluated at 0.01–10 mg/mL final bath concentration in isolated rabbit jejunum and tracheal tissues, using PowerLab data acquisition system (Transonic Systems Inc., Ithaca, NY). In vivo antidiarrhoeal activity was evaluated in castor oil-induced diarrhoeal mice at the dose of 300 and 500 mg of crude extract orally.

Results: Crude extract of N. ruderalis completely relaxed spontaneously contracting, high K⁺ (80 mM) and carbachol (1 μM) induced contracted jejunum with an EC₅₀ value of 5.85 (5.45–6.27), 4.0 (3.80–4.23) and 2.86 (2.48–3.29), similar to verapamil. Nr.Cr relaxed high K⁺ and carbachol induced contractions, at 5 and 10 mg/mL with an EC₅₀ value of 2.37 (2.11–2.67) and 3.26 (2.9–3.67), respectively, and also displaced calcium concentration–response curves toward right at 0.1 and 0.3 mg/mL. Nr.Cr exhibited antidiarrhoeal protection at a dose of 300 and 500 mg/kg, similar to verapamil, whereas no acute toxicity signs were seen up to 5 g/kg in healthy mice.

Discussion and conclusion: Results suggest the presence of spasmolytic and broncho-relaxant effects in the crude extract of N. ruderalis, possibly mediated through calcium channel-blocking activity, providing the pharmacological basis for its traditional uses in gastrointestinal and airway disorders.

Keywords:

• Spasmolytic
• broncho-relaxant
• antidiarrhoeal
• calcium channel-blocking activity

Acknowledgements

The authors are grateful to Prof. Dr. MH Qazi, Director CRiMM (Center for Research in Molecular Medicine), The University of Lahore, Lahore, Pakistan, for providing the research facilities. All the researchers acknowledge his support and guidance that made it possible to complete this research work successfully.

Disclosure statement

All authors read and approved the final manuscript for publication. The authors report no declarations of interest.