Indian culinary plants enhance glucose-induced insulin secretion and glucose consumption in INS-1 β-cells and 3T3-L1 adipocytes

Antidiabetic potential of fenugreek (Trigonella foenum-graecum): A magic herb for diabetes mellitus

Fenugreek (Trigonella foenum-graecum) is a widely grown dietary herb in Asia, and its seeds are traditionally used for several diseases, including diabetes. The seeds and leaves possess a variety of compounds that play an important role in regulating their hypoglycemic effect. However, so far, no extensive systematic review exists on its antidiabetic effect, highlighting the molecular mechanisms and isolated compounds. The purpose of this review is to summarize the preclinical and clinical antidiabetic properties of fenugreek and its isolated compounds by focusing on underlying mechanisms. PubMed, Google Scholar, Science Direct, and Scopus databases were searched to retrieve articles until June, 2024. Preclinical studies demonstrated that the antidiabetic effect of fenugreek was mostly associated with enhanced glucose transporter type-4 (GLUT4) translocation and hexokinase activity, decreased glucose-6-phosphatase and fructose-1,6-bisphosphatase activities, inhibited α-amylase and maltase activities, protected β cells, and increased insulin release. Furthermore, few studies have reported its role as a glucagon-like peptide-1 (GLP-1) modulator, 5'-AMP-activated kinase (AMPK) activator, and dipeptidyl peptidase-IV (DPP-IV) inhibitor. Further clinical trials showed that fenugreek seeds improved blood glucose levels, insulin resistance, insulin sensitivity, and lipid profiles. This study highlights significant evidence of the antidiabetic effect of fenugreek and its isolated compounds; therefore, it could be a potential therapy for diabetes.

In Vitro Studies of Pumpkin (Cucurbita moschata var. Kashi Harit) Seed Protein Fraction(s) to Evaluate Anticancer and Antidiabetic Properties

Chronic diseases like cancer and diabetes are the major public health concerns of India and worldwide. Nowadays, plant-derived products are in great demand for the treatment of these diseases. Pumpkin seeds are traditionally implicated for their pharmacological properties, as exemplified by benign prostatic hyperplasia. Earlier, pumpkin seed proteins were extracted by the Osborne method, and their functional and nutritional qualities were evaluated. Here, the aim is to assess in vitro, the anticancer and antidiabetic properties of seed protein fractions. HepG2, MDA-MB-231, and MCF-7 cell lines were treated with water-soluble (WF) and alkali-soluble fractions (AF) to assess cytotoxicity, while pancreatic β-cells and insulin resistance (IR) - HepG2 cell lines were treated with WF to evaluate the antidiabetic potential. WF and AF showed cytotoxic effects towards HepG2 and MDA-MB-231 cell lines, suggesting apoptosis-mediated anticancerous activity. WF potentiates glucose-stimulated insulin secretion in pancreatic β-cells, in a dose-dependent manner. In IR-HepG2 cell line studies, control, metformin, and WF-treated groups showed uptake of glucose, when compared to the diabetic group, which is well-correlated with the upregulated expressions of GLUT2 and GLUT4 transporters in these groups. These results indicate that proteins from WF and AF may have anticancerous and antidiabetic properties and thus have the potential to utilize pumpkin proteins in the management of cancer and diabetes.

Effects of Polyphenols on Insulin Resistance

Insulin resistance (IR) is apparent when tissues responsible for clearing glucose from the blood, such as adipose and muscle, do not respond properly to appropriate signals. IR is estimated based on fasting blood glucose and insulin, but some measures also incorporate an oral glucose challenge. Certain (poly)phenols, as supplements or in foods, can improve insulin resistance by several mechanisms including lowering postprandial glucose, modulating glucose transport, affecting insulin signalling pathways, and by protecting against damage to insulin-secreting pancreatic β-cells. As shown by intervention studies on volunteers, the most promising candidates for improving insulin resistance are (-)-epicatechin, (-)-epicatechin-containing foods and anthocyanins. It is possible that quercetin and phenolic acids may also be active, but data from intervention studies are mixed. Longer term and especially dose-response studies on mildly insulin resistant participants are required to establish the extent to which (poly)phenols and (poly)phenol-rich foods may improve insulin resistance in compromised groups.

Neem (Azadirachta indica): An indian traditional panacea with modern molecular basis

BACKGROUND

For centuries, agents derived from natural sources (mother nature), especially plants have been the primary source of medicine. Neem, also referred to as Azadirachta indica is one such plant that has been so named because it provides freedom from all diseases, and used for thousands of years in Indian and African continents. Different parts of the plant including flowers, leaves, seeds and bark have been used to treat both acute and chronic human diseases; and used as insecticide; antimicrobial, larvicidal, antimalarial, antibacterial, antiviral, and spermicidal.

PURPOSE

What is there in neem and how it manifests its wide variety of effects is the focus of this review. How neem and its constituents modulate various cellular pathways is discussed. The animal and human studies carried out with neem and its constituents is also discussed.

CONCLUSION

Over 1000 research articles published on neem has uncovered over 300 structurally diverse constituents, one third of which are limonoids including nimbolide, azadarachtin, and gedunin. These agents manifest their effects by modulating multiple cell signaling pathways.

Antihyperglycemic glucosylated coumaroyltyramine derivatives from Teucrium viscidum

Eight new glucosylated coumaroyltyramine derivatives, teuvissides A-H (1-8), were isolated from whole plants of Teucrium viscidum. Their structures were elucidated using spectroscopic data and chemical methods. The antihyperglycemic activities of these compounds were evaluated in HepG2 cells and 3T3-L1 adipocytes, and all of the isolates elicited different levels of glucose consumption at a concentration of 2.0 μM. Teuvissides A (1), B (2), and F (6) induced 2.2-, 2.1-, and 2.2-fold changes, respectively, in the levels of glucose consumption in HepG2 cells and 2.5-, 2.1-, and 2.3-fold changes, respectively, in 3T3-L1 adipocytes relative to the basal levels.