Enhancement of nutraceutical and anti-diabetic potential of fenugreek (Trigonella foenum-graecum). Sprouts with natural elicitors

Saudi Pharm J. 2023 Jan;31(1):1-13. doi: 10.1016/j.jsps.2022.11.001. Epub 2022 Nov 9.

Abstract

Trigonella foenum-graecum has been extensively used for centuries in traditional medicine systems for the cure of health ailments including diabetes. Improving the medicinal attributes of plants through the elicitation strategy is gaining great interest in the recent past. In the current study, an attempt is made to reveal the role and possible mechanism of action of vitamin C elicit phytochemical-rich aqueous extract of 4th day germinated IM6 genotype fenugreek sprouts in the form of lyophilized powder (IM6E) under both in vitro and in vivo conditions. The IM6E demonstrated strong α-glucosidase activity (95.24 %) and moderate α-amylase and invertase inhibition activities under in vitro conditions. The High Performance Thin Layer Chromatography (HPTLC) based analysis demonstrated that IM6E possess significantly higher concentration of phenolic phytochemical quercetin (0.148 %) as compared to diosgenin and trigonelline bioactive anti-diabetic nutraceuticals. In normal rats after loading with glucose and sucrose, the IM6E administration in a dose-dependent manner significantly reduced the post-prandial hyperglycemia, in a similar fashion as the anti-diabetic drug voglibose as evident from the area under curves (AUC) of oral glucose tolerance test (OGTT) and oral sucrose tolerance test (OSTT) tests. The administration of IM6E in streptozotocin (STZ) induced diabetic rats drastically improved the antioxidant activity of plasma in them as determined by Ferric Reducing Ability of Plasma (FRAP) and the effect was found to be dose-dependent. The oral administration of IM6E in diabetic rats normalized almost all the deregulated biochemical markers like liver enzymes, lipids and significantly decreased higher blood glucose levels with increasing insulin levels as compared to diabetic control. The best concentration of IM6E was found to be 300 mg/kg b.w after 21 days of experimentation. The intra-peritoneal glucose tolerance test (IPGTT) in diabetic rats responded very well to IM6E treatment and 100 mg/kg.b.w. behaved almost like the administration of 0.5U insulin/kg bw, and thus indicating the insulinotropic nature of IM6E. Our findings clearly reveal the use of IM6E for diabetes management and at the same it possesses great potential when combined with voglibose to ameliorate diabetes and its associated complications to a greater extent due to synergistic effects as compared to monotherapy. However, more clinical trials need to be performed before recommending IM6E as an anti-diabetic alternative medicine.

Keywords: Diabetes; Hypoglycemic effect; Phytochemicals; Quercetin; Streptozotocin; T. foenum-graecum; Toxicity.