Ethnomedicinal application of native remedies used against diabetes and related complications in Mauritius.
Ethnopharmacological relevance: Notoriously, the tropical island of Mauritius has one of the highest prevalence of diabetes worldwide and the economic burden associated with it is alarming. The use of native remedies (NRs) is well anchored in the local culture and it continues to be the cornerstone of therapy for diabetic patients. However, there is currently a dearth of updated primary data on NRs used by Mauritians against diabetes and diabetes related complications (DRCs). This study was therefore designed to record, analyze and document orally transmitted ethnopharmacological knowledge from diabetic patients and traditional medicine practitioners (TMPs) in Mauritius concerning NRs commonly used against diabetes and DRCs which might open new avenues to initiate novel antidiabetic drugs discovery. Materials and methods: Data was collected following interviews from diabetic patients (n¼328) and TMPs (n¼20). Eleven quantitative indexes, namely informant consensus factor (FIC), fidelity level (FL), use value (UV), relative frequency of citation (RFC), relative importance (RI), cultural importance index (CII), index of agreement on remedies (IAR), cultural agreement index (CAI), quality use value (QUV), quality use agreement value (QUAV) and ethnobotanicity index (EI) were calculated. Statistical analysis such as Pearson correlation and Chi-squared test were performed to determine any association. Results: A total of 111 plant species distributed over 56 families, 30 polyherbal formulations and 16 animal species were documented to be traditionally used against diabetes and DRCs. For the first time 8 endemic plants have been recorded to be used against diabetes and DRCs from Mauritius. The most encountered medicinal plant family was Asteraceae. According to the EI, 16.2% of the native plants in Mauritius were used against diabetes and DRCs. As far as we know, Vangueria madagascariensis, Apium graveolens, Petroselinum crispum and Rubus alceifolius with high RFC values are recorded against diabetes and DRCs for the first time. Sociodemographic characteristics (age, gender, income, religious belief, education and residence) were found to significantly (po0.05) influence the use of NRs. The average FIC for all ailments for plant and animal products were 0.94 and 0.87 respectively. Bryophyllum pinnatum, a native plant to Mauritius scored a high FL value (100%) used against diabetic neuropathy, Allium sativum had the highest RI value (2.00) due to its versatility, Aloe vera had the highest RFC (0.61), the CII (0.640) and the highest CAI value (0.635), Psidium guajava had the highest QUAV (0.961) which indicates its high bioactivity and Allium cepa was reported as the most effective plant species (QUV¼0.965). According to UV, the most important species was Morinda citrifolia (1.21). Panoply of animal products were reported whereby fish (39.7%) was recorded as the most utilised zootherapy and Salmo salar scored the highest FL (100%) for diabetes. Some animal species (n¼14) not previously documented against diabetes and DRCs are reported in the present study. Conclusion: Our present investigation revealed that the use of NRs constitutes the common legacy of Mauritians and despite the penetration of allopathic medicine; NRs continue to play a crucial role in the primary health care system of Mauritius. To this effect, it is of uttermost importance to record this knowledge before it disappears. In addition, further experimental investigations are required to elucidate the pharmacological properties of the reported medicinal flora and fauna of Mauritius