Limits...
Targeting mosquito FREP1 with a fungal metabolite blocks malaria transmission.

Niu G, Wang B, Zhang G, King JB, Cichewicz RH, Li J - Sci Rep (2015)

Bottom Line: The inhibition specificity was confirmed by immunofluorescence assays.Therefore, disruption of the interaction between FREP1 and parasites effectively reduces Plasmodium infection in mosquitoes.Targeting FREP1 with small molecules is thus an effective novel approach to block malaria transmission.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.

ABSTRACT
Inhibiting Plasmodium development in mosquitoes will block malaria transmission. Fibrinogen-related protein 1 (FREP1) is critical for parasite infection in Anopheles gambiae and facilitates Plasmodium invasion in mosquitoes through interacting with gametocytes and ookinetes. To test the hypothesis that small molecules that disrupt this interaction will prevent parasites from infecting mosquitoes, we developed an ELISA-based method to screen a fungal extract library. We obtained a candidate fungal extract of Aspergillus niger that inhibited the interaction between FREP1 and P. falciparum infected cells by about 92%. The inhibition specificity was confirmed by immunofluorescence assays. Notably, feeding mosquitoes with the candidate fungal extract significantly inhibited P. falciparum infection in the midgut without cytotoxicity or inhibition of the development of P. falciparum gametocytes or ookinetes. A bioactive natural product that prevents FREP1 from binding to gametocytes or ookinetes was isolated and identified as P-orlandin. Importantly, the nontoxic orlandin significantly reduced P. falciparum infection intensity in mosquitoes. Therefore, disruption of the interaction between FREP1 and parasites effectively reduces Plasmodium infection in mosquitoes. Targeting FREP1 with small molecules is thus an effective novel approach to block malaria transmission.

No MeSH data available.


Related in: MedlinePlus

P-orlandin does not exhibit any cytotoxicity.(a) Orlandin did not lyse human blood cells at the concentration of 300 μM or lower. (b) Orlandin did not show apparent cytotoxicity to the mosquito cell line Sua5B at the concentration of 100 μM or lower.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4593950&req=5

f9: P-orlandin does not exhibit any cytotoxicity.(a) Orlandin did not lyse human blood cells at the concentration of 300 μM or lower. (b) Orlandin did not show apparent cytotoxicity to the mosquito cell line Sua5B at the concentration of 100 μM or lower.

Mentions: Orlandin was previously reported to be nontoxic to mammals in chick and rat bioassays32. We further determined its general cytotoxicity. First we analyzed the hemolytic activity of orlandin. Different concentrations of orlandin were mixed with human RBC and incubated at 37 °C for 2 hrs. Saponin was used as a positive control to lyse blood cells. The OD540 of the supernatant was measured to quantify the hemolytic activity. As shown in Fig. 9a, orlandin did not lyse RBC at 300 μM or lower. Next, we examined whether orlandin is toxic to mosquito cell lines. A serial dilution of orlandin was incubated with An. gambiae cell line Sua5B for two days. The live and dead cells were recorded in each treatment. The wells without the addition of orlandin were used as a control. The results indicate that orlandin did not kill the cells (Fig. 9b, red line) or inhibit the cell growth (Fig. 9b, green line) at the concentration of 100 μM or below. Together, our data support the fact that orlandin is nontoxic to RBC and mosquito cells.


Targeting mosquito FREP1 with a fungal metabolite blocks malaria transmission.

Niu G, Wang B, Zhang G, King JB, Cichewicz RH, Li J - Sci Rep (2015)

P-orlandin does not exhibit any cytotoxicity.(a) Orlandin did not lyse human blood cells at the concentration of 300 μM or lower. (b) Orlandin did not show apparent cytotoxicity to the mosquito cell line Sua5B at the concentration of 100 μM or lower.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4593950&req=5

f9: P-orlandin does not exhibit any cytotoxicity.(a) Orlandin did not lyse human blood cells at the concentration of 300 μM or lower. (b) Orlandin did not show apparent cytotoxicity to the mosquito cell line Sua5B at the concentration of 100 μM or lower.
Mentions: Orlandin was previously reported to be nontoxic to mammals in chick and rat bioassays32. We further determined its general cytotoxicity. First we analyzed the hemolytic activity of orlandin. Different concentrations of orlandin were mixed with human RBC and incubated at 37 °C for 2 hrs. Saponin was used as a positive control to lyse blood cells. The OD540 of the supernatant was measured to quantify the hemolytic activity. As shown in Fig. 9a, orlandin did not lyse RBC at 300 μM or lower. Next, we examined whether orlandin is toxic to mosquito cell lines. A serial dilution of orlandin was incubated with An. gambiae cell line Sua5B for two days. The live and dead cells were recorded in each treatment. The wells without the addition of orlandin were used as a control. The results indicate that orlandin did not kill the cells (Fig. 9b, red line) or inhibit the cell growth (Fig. 9b, green line) at the concentration of 100 μM or below. Together, our data support the fact that orlandin is nontoxic to RBC and mosquito cells.

Bottom Line: The inhibition specificity was confirmed by immunofluorescence assays.Therefore, disruption of the interaction between FREP1 and parasites effectively reduces Plasmodium infection in mosquitoes.Targeting FREP1 with small molecules is thus an effective novel approach to block malaria transmission.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, USA.

ABSTRACT
Inhibiting Plasmodium development in mosquitoes will block malaria transmission. Fibrinogen-related protein 1 (FREP1) is critical for parasite infection in Anopheles gambiae and facilitates Plasmodium invasion in mosquitoes through interacting with gametocytes and ookinetes. To test the hypothesis that small molecules that disrupt this interaction will prevent parasites from infecting mosquitoes, we developed an ELISA-based method to screen a fungal extract library. We obtained a candidate fungal extract of Aspergillus niger that inhibited the interaction between FREP1 and P. falciparum infected cells by about 92%. The inhibition specificity was confirmed by immunofluorescence assays. Notably, feeding mosquitoes with the candidate fungal extract significantly inhibited P. falciparum infection in the midgut without cytotoxicity or inhibition of the development of P. falciparum gametocytes or ookinetes. A bioactive natural product that prevents FREP1 from binding to gametocytes or ookinetes was isolated and identified as P-orlandin. Importantly, the nontoxic orlandin significantly reduced P. falciparum infection intensity in mosquitoes. Therefore, disruption of the interaction between FREP1 and parasites effectively reduces Plasmodium infection in mosquitoes. Targeting FREP1 with small molecules is thus an effective novel approach to block malaria transmission.

No MeSH data available.


Related in: MedlinePlus