Exploring the Carbamazepine Interaction with Human Pregnane X Receptor and Effect on ABCC2 Using in Vitro and in Silico Approach.

PURPOSE: Over expression of ATP-binding cassette transporters is considered one of the major reasons for non-responsiveness to antiepileptic drugs. Carbamazepine (CBZ), one of first line antiepileptic drug is known to influence ABCC2 expression but its exact molecular mechanism is unknown. METHODS: We investigated the effect of CBZ on expression of ABCC2 and pregnane X receptor (PXR) in HepG2 cell line and compared with hyperforin (agonist of PXR) and ketoconazole (antagonist of PXR) through realtime PCR and western blot assay. Involvement of PXR was demonstrated through nuclear translocation and RNA interference and related effect of CBZ on ABCC2 through functional activity assay. Molecular docking and dynamic simulation approach was used to understand the interaction of CBZ with PXR. RESULTS: CBZ and hyperforin increased the PXR and ABCC2 expression whereas reversed when present it in combination with ketoconazole. Experiments confirmed CBZ induced ABCC2 expression is PXR dependent. Molecular dynamic (MD) simulation and in vitro experiment indicated possibility of CBZ to be PXR agonist and PXR residue Gln285 to be important for CBZ-PXR interaction. CONCLUSIONS: CBZ alters the functional activity of ABCC2 through PXR, which in turn can interfere with therapy. Mutational analysis of residues revealed the importance of Gln285 in ligand interaction.

A novel integrase targeting agent to explore the future prospective of HIV eradication: dolutegravir.

Out of the 15 discrete proteins encoding the total amount of genetic information in the chromosomes of human immunodeficiency virus type 1; three perform the vital enzymatic functions i.e. a reverse transcription, an integration, and proteolysis. The HIV integrase is the new validated drug target against AIDS amongst all essential enzymes due to the lack of the human homologue. In last few years quite, a few but potent inhibitors inhibiting HIV-1 integrase have been recognized and hence have gained a state-of-the-art for treating the infection caused by HIV-1. The greater understanding of HIV-integrase biological structure has further lead to continuous efforts for the proposal of novel inhibitors targeting diverse steps in the progression of integration with the primary goal to overcome resistance due to the rapid occurrence of integrase mutations in the treated patients. This review is focused on various aspects of the recently approved HIV integrase inhibitor "dolutegravir", its efficacy, safety profiles with the clinical data and molecular modeling studies highlighting its importance over the already approved HIV-integrase inhibitors.