Probing key targets in insulin signaling and adipogenesis using a methanolic extract of Costus pictus and its bioactive molecule, methyl tetracosanoate.

A methanolic extract of Costus pictus (CPME) showed optimum anti-diabetic activity at 100 ng/ml. Bioactivity-guided purification of CPME led to the isolation of methyl tetracosanoate (MT) which showed an optimum glucose uptake at 1 ng/ml. CPME at 10 mug/ml inhibited adipogenesis whereas fully differentiated adipocytes exhibited a 3-fold increase in lipid accumulation compared to pre-adipocytes. Gene and protein expression of key targets in insulin signaling and adipogenesis pathway revealed that CPME exhibited anti-diabetic activity along with anti-adipogenic activity whereas MT demonstrated only anti-diabetic activity.

Activation of Candida rugosa lipase at alkane-aqueous interfaces: a molecular dynamics study.

The effect of solvent hydrophobicity on activation of Candida rugosa lipase (CRL) was investigated by performing molecular dynamics simulations for four nano seconds (ns). The closed/inactive conformer of CRL (PDB code 1TRH) was solvated in three alkane-aqueous environments. The alkanes aggregated in a predominantly aqueous environment and by 1 ns a stable spherical alkane-aqueous interface had formed. This led to the interfacial activation of CRL. On analyzing the simulated conformers with the closed conformer of CRL, the flap was found to have opened from a closed state by 7.7 A, 10.2 A, 13.1 A at hexane-aqueous, octane-aqueous, and decane-aqueous interfaces. Further, essential dynamics analysis revealed that major anharmonic fluctuations were confined to residues 64-81, the flap of CRL.