Cardiovascular effects of Boophone disticha aqueous ethanolic extract on early maternally separated BALB/C mice

Ethnopharmacological relevanceThere are a number of reports from traditional medical practice in Zimbabwe and neighboring countries and few in vitro studies suggesting an effect with extracts of Boophone disticha in some forms of anxiety disorder.Aim of the studyIn order to validate the use of Boophone disticha in treatment of anxiety, this study was set to determine the effects of the plant extracts on blood pressure (BP) and heart rate (HR) in adult BALB/c mice subjected to repeated early maternal separation (MS) stress.Materials and methodsTo test whether early life stress increases anxiety in mice, non-invasive tail cuff method was used to examine the autonomic nervous system activity by assessing cardiovascular reactivity and response to acute mixing stress (AMS) and restraint stress (RS) in adult mice subjected to early postnatal stress as compared to control. AMS-induced cardiovascular response was then evaluated in adult MS mice treated with Boophone disticha as compared to vehicle and diazepam.ResultsComparisons of the BP and HR measurements indicated that MS significantly reduced AMS-induced HR responses in BALB/c mice when compared with control. Boophone disticha treatment significantly reduced AMS-induced BP response in BALB/c MS mice as compared to vehicle and diazepam treatments.ConclusionsOur findings demonstrate for the first time that postnatal stress can induce short-term changes in the sensitivity of the cardiovascular system to subsequent stress which can be reduced by treatment with a freeze dried aqueous ethanolic extract of Boophone disticha.

Diagram showing changes in (a) systolic blood pressure (SBP), (b) diastolic blood pressure (DBP), (c) mean arterial pressure (MAP) and (d) heart rate (HR) in BALB/c mice after maternal separation Group B (MS+NS) affected as compared to control Group A (C+NS) two days (postnatal day 78) after receiving six daily doses of normal saline (NS, vehicle). Maternally separated mice were also treated with either Boophone disticha (BD) aqueous ethanolic extract Group C (MS+LDBD), D MS+MDBD) and E (HDBD) receiving low, medium and high doses (10, 25 and 40 mg/kg body weight (BW) respectively or 1 mg/kg BW diazepam (Group F (MS+DZP)).165