Sambiloto (Andrographis Paniculata) Increases Glucagon–Like Peptide 1 Concentration in Prediabetes: A Double–Blind, Randomized, Placebo-Controlled Trial

Background : The extract of Andrographis paniculata (Burm. F.) Wall. Ex. Nees. ( sambiloto ) (穿心蓮 chuān xīn lián) has been reported to have antidiabetic effect on mice models and has been used traditionally in the community. The exact mechanism of  sambiloto extract in decreasing plasma glucose is unclear, so we investigated the role of sambiloto extract in incretin pathway in healthy and prediabetes subjects. Methods: This study was a double-blind, cross-over, randomized placebo-controlled trial. It was conducted to 38 healthy and 35 prediabetes subjects. All subjects were exposed to both intervention sambiloto extract and placebo alternately. All subjects were randomly assigned to receive first intervention for 14 days. There was wash out period between subsequent intervention. Primary outcome was glucagon-like peptide 1 (GLP-1) concentration and secondary outcomes were fasting insulin, 2-hour postprandial insulin, homeostasis model assessment of insulin resistance (HOMA-IR), fasting blood glucose, 2-hour postprandial blood glucose, dipeptidyl peptidase-4 (DPP-4), and glycated albumin before and after intervention. Result: After the intervention, GLP-1 concentration significantly increased in prediabetes by 19.6% compared to the placebo (p = 0.043). There were no significant differences in the changes of fasting insulin, 2-hour postprandial insulin, HOMA-IR, fasting blood glucose, 2-hour postprandial blood glucose, DPP-4, and glycated albumin levels after intervention.  Sambiloto extract did not inhibit DPP-4 enzyme in healthy and prediabetes subjects. Conclusion: Sambiloto extract increased GLP-1 concentration without inhibiting DPP-4 enzyme in prediabetes subjects. Trial Registration : Clinical Trials.gov ID : NCT03455049. Registered 6 March 2018 – Retrospectevly Registered, https://clinicaltrials.gov/ct2/show/NCT03455049.