Barosmin against postprandial hyperglycemia: outputs from computational prediction to functional responses in vitro

Abstract

Previously, barosmin has been demonstrated to possess anti-diabetic action. However, its effect to inhibit α-amylase and α-glucosidase, including glucose utilization efficacy, has yet to be revealed. Hence, the current study attempted to assess the efficiency of barosmin in inhibiting the α-amylase, α -glucosidase, and dipeptidyl peptidase 4 enzymes, including glucose uptake efficacy. Molecular docking and simulation were performed using AutoDock Vina and Gromacs respectively followed by gene ontology analysis using the database for annotation, visualization, and integrated discovery. Further, in vitro enzyme inhibitory activities and glucose uptake assay were performed in L6 cell lines. Density functional theory analysis detailed mechanistic insights into the crucial interaction sites of barosmin of which the electron-dense region was prone to nucleophilic attack (O-atoms) whereas hydroxyl groups (-OH) showed affinity for electrophilic attacks. Barosmin showed good binding affinity with α-amylase (-9.2 kcal/mol), α-glucosidase (-10.7 kcal/mol), and dipeptidyl peptidase 4 (-10.0 kcal/mol). Barosmin formed stable nonbonded contacts with active site residues of aforementioned enzymes throughout 200 ns molecular dynamics simulation. Further, it regulated pathway concerned with glucose homeostasis i.e. tumor necrosis factor signaling pathway. In addition, barosmin showed α-amylase (IC₅₀= 95.77 ± 23.33 µg/mL), α-glucosidase (IC₅₀= 68.13 ± 2.95 µg/mL), and dipeptidyl peptidase 4 (IC₅₀= 13.27 ± 1.99 µg/mL) inhibitory activities including glucose uptake efficacy in L6 cell lines (EC₅₀= 12.46 ± 0.90 µg/mL) in the presence of insulin. This study presents the efficacy of the barosmin to inhibit α-amylase and α-glucosidase and glucose uptake efficacy in L6 cell lines via the use of multiple system biology tools and in vitro techniques.

Communicated by Ramaswamy H. Sarma

Keywords:

• α-amylase
• α-glucosidase
• molecular docking
• barosmin
• in vitro

Acknowledgment

Authors are grateful to Ms. Bhavana R. Shivankar (UGC-Senior Research Fellow (SRF), CSIR-NCL) and Dr. Sailaja Krishnamurty (Senior Principal Scientist, CSIR-NCL) for their extended support to perform DFT calculations using Gaussian and utilize their computational resources for the same. We also acknowledge the supercomputing facility PARAM Brahma under the National Supercomputing Mission, Government of India at the Indian Institute of Science Education and Research, Pune for its smooth accessibility during the research work. The graphical abstract and Figure 16 were drawn in BioRender: Scientific Image and Illustration Software (https://www.biorender.com/).

Author contribution

PK: Conceptualized, experimented, drafted, edited, reviewed, and finalized the entire work. PD, VSP, AS, AS, AA, AR, AJ, and VVB: Equal contribution in assistance in experimentation and drafting the draft.

Disclosure statement

All the authors of this manuscript have no conflict of interest to declare in any financial or non-financial means.

Ethical statement

This experiment did not include any animal or human participation.

Additional information

Funding

This work has not received any funds from national or international agencies to declare.