The Influence of Fatty Acid Methyl Esters (FAMEs) in the Biochemistry and the Na super(+)/K super(+)-ATPase Activity of Culex quinquefasciatus Larvae

• Published in: The Journal of membrane biology Vol. 249; no. 4; pp. 459 - 467
• Main Authors: Silva, Lilian ND, Ribeiro-Neto, Jose A, Valadares, Jessica MM, Costa, Mariana M, Lima, Luciana ARS, Grillo, Luciano AM, Cortes, Vanessa F, Santos, Herica L, Alves, Stenio N, Barbosa, Leandro A
• Format: Journal Article
• Language: English
• Published: 01.08.2016
• Subjects: Culex quinquefasciatus
• ISSN: 0022-2631; 1432-1424
• DOI: 10.1007/s00232-016-9886-1

Culex quinquefasciatus is the main vector of lymphatic filariasis and combating this insect is of great importance to public health. There are reports of insects that are resistant to the products currently used to control this vector, and therefore, the search for new products has increased. In the present study, we have evaluated the effects of fatty acid methyl esters (FAMEs) that showed larvicidal activity against C. quinquefasciatus, on glucose, total protein, and triacylglycerol contents and Na super(+)/K super(+)-ATPase activity in mosquito larvae. The exposure of the fourth instar larvae to the compounds caused a decrease in the total protein content and an increase in the activity of the Na super(+)/K super(+)-ATPase . Furthermore, the direct effect of FAMEs on cell membrane was assessed on purified pig kidney Na super(+)/K super(+)-ATPase membranes, erythrocyte ghost membranes, and larvae membrane preparation. No modifications on total phospholipids and cholesterol content were found after FAMEs 20 min treatment on larvae membrane preparation, but only 360 mu g/mL FAME 2 was able to decrease total phospholipid of erythrocyte ghost membrane. Moreover, only 60 and 360 mu g/mL FAME 3 caused an activation of purified Na super(+)/K super(+)-ATPase , that was an opposite effect of FAMEs treatment in larvae membrane preparation, and caused an inhibition of the pump activity. These data together suggest that maybe FAMEs can modulate the Na super(+)/K super(+)-ATPase on intact larvae for such mechanisms and not for a direct effect, one time that the direct effect of FAMEs in membrane preparation decreased the activity of Na super(+)/K super(+)-ATPase . The biochemical changes caused by the compounds were significant and may negatively influence the development and survival of C. quinquefasciatus larvae.