Integrated in vitro, in silico, and in vivo approaches to elucidate the antidiabetic mechanisms of Cicer arietinum and Hordeum vulgare extract and secondary metabolites

Diabetes mellitus is a group of metabolic disorders that can lead to severe health problems, and the current treatments often have harmful side effects. Therefore, there is a growing interest in discovering new antidiabetic drugs with fewer adverse effects, and natural products are a promising source for this purpose. Cicer arietinum and Hordeum vulgare are plants with high levels of phytochemicals that have been shown to have therapeutic properties. This study investigates the anti-diabetic potential of C. arietinum and H. vulgare seeds and their secondary metabolites. We employed a comprehensive approach combining in vitro, in silico, and in vivo methods to evaluate the efficacy of the compounds. Our findings reveal that the extracts of C. arietinum (IC₅₀ 55.08 μg/mL) and H. vulgare (IC₅₀ 115.8 ± 5 μg/mL) demonstrated a stronger inhibitory effect on α-amylase compared to acarbose (standard drug) (IC₅₀ 196.3 ± 10 μg/mL). Similarly, both C. arietinum and H. vulgare exhibited significant inhibitory activity against α-glucosidase (IC₅₀ 100.2 ± 5 μg/mL and IC₅₀ 216.2 ± 5 μg/mL, respectively) compared to acarbose (IC₅₀ 246.5 ± 10 μg/mL). To further investigate their mechanism of action, a computational screening of 194 phytochemicals from these plants was conducted, followed by molecular docking with α-amylase (PDB ID#1B2Y) and α-Glucosidase (PDB ID# 5NN8) receptors. According to the binding affinities and molecular dynamics (MD) simulations, Medicagol, Euphol, Stigmasterol, and Beta-Sitosterol emerged as promising candidates for diabetes treatment. Molecular dynamics showed that Medicagol was a strong inhibitor against selected receptor proteins because the ligand-protein complexes remained stabilized during the entire simulation time of 100 ns. In vitro analysis also confirmed that Medicagol, stigmasterol, and Euphol have significant potential for type 2 diabetes prevention via inhibition of carbohydrates hydrolyzing enzymes. In vivo study demonstrated significant therapeutic effects in STZ-induced diabetes mice. Including reductions in hyperlipidemia, hyperglycemia, and insulin resistance. Histopathological analysis revealed that plant extracts mitigated STZ-induced pancreatic and liver damage. Additionally, extracts enhanced antioxidant defenses by increasing SOD, CAT, and GSH levels, while decreasing MDA levels in the liver, kidneys, and pancreas, highlighting their protective role against oxidative stress. These results support the potential of Cicer arietinum and Hordeum vulgare as natural sources for developing antidiabetic agents.