Designing Potent α-Glucosidase Inhibitors: A Synthesis and QSAR Modeling Approach for Biscoumarin Derivatives

Nineteen biscoumarins were synthesized, well-characterized, and evaluated against α-glucosidases in vitro. Of these, six compounds (10, 12, 16, and 17-19) were newly synthesized and not previously reported in the chemical literature. The majority of the synthesized derivatives demonstrated significant inhibitory activity. A quantitative structure-activity relationship (QSAR) model was developed, revealing a strong correlation between the anti-α-glucosidase activity and selected molecular descriptors. Based on this model, two new compounds (18 and 19) were designed, which exhibited the strongest inhibition with IC₅₀ values of 0.62 and 1.21 μM, respectively, when compared to the positive control (acarbose) with an IC₅₀ value of 93.63 μM. Enzyme kinetic studies of compounds 18 and 19 revealed their competitive inhibition with K_i values of 3.93 and 1.80 μM, respectively. Computational studies demonstrated that compound 18 could be inserted into the original binding site (OBS) of α-glucosidase MAL12 and form multiple hydrophobic interactions with nearby amino acids, with the bromo group playing an essential role in enhancing the binding strength and stability at the OBS of the enzyme based on the quantum mechanical calculations using the fragment molecular orbital method. These findings provide valuable insights into the design of potent α-glucosidase inhibitors, which may have potential therapeutic applications in the treatment of diabetes and related diseases.

Cichoriin, a Biocoumarin, Mitigates Oxidative Stress and Associated Adverse Dysfunctions on High-Fat Diet-Induced Obesity in Rats

Metabolic dysfunctions linked to obesity carry the risk of co-morbidities such as diabetes, hepatorenal, and cardiovascular diseases. Coumarins are believed to display several biological effects on diverse adverse health conditions. This study was conducted to uncover the impact of cichoriin on high-fat diet (HFD)-induced obese rats. Methods: Obesity was induced in twenty rats by exposure to an HFD for six weeks. The rats were randomly divided into five groups; group I comprised five healthy rats and was considered the control one. On the other hand, the HFD-induced rats were divided into the following (five per each group): group II (the HFD group), groups III (cichoriin 50 mg/kg) and IV (cichoriin 100 mg/kg) as the treatment groups, and group V received atorvastatin (10 mg/kg) (as a standard). Triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), alanine transaminase (ALT), aspartate transaminase (AST), creatine kinase MB (CK-MB), urea, creatinine, the hepatic and renal malondialdehyde (MDA) as well as reduced glutathione (GSH) levels were assessed. Histopathological analysis of the heart, kidney, and liver tissues was investigated. mRNA and protein expressions of the peroxisome proliferator-activated receptor gamma (PPAR-γ) were estimated. Results: The administration of cichoriin alleviated HFD-induced metabolic dysfunctions and improved the histopathological characteristics of the heart, kidney, and liver. Additionally, the treatment improved the lipid profile and hepatic and renal functions, as well as the oxidative balance state. Cichoriin demonstrated an upregulation of the mRNA and protein expressions of PPAR-γ. Taken together, these findings are the first report on the beneficial role of cichoriin in alleviating adverse metabolic effects in HFD-induced obesity and adapting it into an innovative obesity management strategy.