Combating Type-2
diabetes mellitus is a pivotal challenge in front of the present world. Several lines of
therapy are in practice for resisting this deadly disease which often culminates with cardiovascular complexities, neuropathy and retinopathy. Among various
therapies, administration of
alpha glucosidase inhibitors is common and widely practiced. Sulfonylurea category of anti diabetic
drug often suffers from cross reactivity with
sulfamethoxazole (SMX), a common
drug in use to treat a handful of microbial
infections. However the specific cellular target generating
postprandial hypoglycemia on SMX administration is till date unraveled. The present work has been initiated to elucidate the effects of a group of
sulfonamide drugs inclusive of SMX for their
amylase inhibitory role. SMX inhibits porcine pancreatic
amylase (PPA) in a noncompetitive mode with an average IC50 value 0.94 mM respectively. Interaction of SMX with PPA is manifested with gradual quenching of
tryptophan fluorescence with concomitant shift in lambda max value (λmax). Binding is governed by entropy driven factor (24.8 cal mol(-1) K(-1)) with unfavorable contribution from enthalpy change. SMX interferes with the activity of
acarbose in a synergistic mode to reduce the effective dose of
acarbose as evident from the in vitro PPA inhibition study. In summary, loss of PPA activity in presence of SMX is indicative of structural changes of PPA which is further augmented in the presence of
acarbose as explained in the schematic model and docking study.