Gene expression levels and inhibitory effect of 7-[(7-methoxy- 4,5-dihydro-1H-benzo[g]indazol-3-yl)carbonyl]-2-phenyl- 5,6,7,8-tetrahydropyrazolo[1,5-a]pyrido[4,3-d]Pyrimidin-9 (1H)-one (MCL) against AP2-I and BDP1 in malaria experimental models

Abstract

Resistance to antimalarial drugs leads a global recurrence of malaria, posing a significant challenge to malaria control. This study aimed to assess gene expression and resistance profiles in clinical isolates, and validate the inhibitory effect of MCL compound against PbAP2-I and PbBDP1 genes in vivo. Malaria prevalence rate throughout the clinical study period stood at 12.24%. Blood samples were obtained from 182 malaria outpatients and 30 P. berghei-infected mice treated with varying MCL concentrations. DNA and RNA were extracted. PfAP2-I, PfBDP1, PfMDR1, and PfK13 genes were amplified using Real-time qPCR and sequenced for mutation profiling. Relative gene expression of AP2-I and BDP1 genes in P. falciparum and P. berghei-treated mice was carried out by Reverse-transcription PCR. The data were analyzed using ANOVA at P<0.05 indicating a significant difference. Relative gene expression results from clinical isolates showed PfAP2-I and PfBDP1 are highly expressed in the trophozoite and schizont stages. The clinical isolates show conserved nucleotide sequences for PfAP2-I, PfBDP1, and PfK13 genes compared to the 3D7 strain. However, Asn86Tyr mutation implicated in antimalarial drug resistance and Leu1312Iso mutation not previously reported to be associated with antimalarial drug resistance were observed for the PfMDR1 gene. MCL inhibited the expression of PbAP2-I (by 4.52 and 8.08 folds) and PbBDP1 (by 37.92 and 79.07 folds) at 40μM and 50μM concentrations after a 7-day, single oral daily dose. Our findings validate MCL’s inhibitory activity against AP2-I and BDP1 genes, hence representing potential new targets of antimalarial therapy for controlling malaria parasite invasion.