Moo-Key Kim

Larvicidal Activity of Australian and Mexican Plant Extracts Against Aedes aegypti and Culex pipiens pallens (Diptera: Culicidae)

Abstract Larvicidal activity of methanol extracts of 22 Australian and 12 Mexican plants against early 4th-instar larvae of Aedes aegypti and Culex pipiens pallens was examined. At 200 ppm, 100% mortality in larvae of A. aegypti and C. pipiens pallens was obtained in extracts of Kigelia pinnata and Ruta chalepensis. The extract of K. pinnata gave 76.3 and 80.3% mortalities in larvae of A. aegypti and C. pipiens pallens at 100 ppm but, at 50 ppm, 23.7 and 42.1% mortality against larvae of A. aegypti and C. pipiens pallens , respectively. The extract of R. chalepensis gave 81.2 and 87.9% mortality in larvae of A. aegypti and C. pipiens pallens at 100 ppm but 23.4 and 53.3% mortality against larvae of A. aegypti and C. pipiens pallens at 50 ppm, respectively. Larvicidal activities of K. pinnata and R. chalepensis extracts were significantly reduced when used at 25 ppm. Consequently, further studies of these plants as possible agents for mosquito control are warranted.

Interleukin-1β Increases Angptl4 (FIAF) Expression via the JNK Signaling Pathway in Osteoblastic MC3T3-E1 Cells

Angiopoietin-like protein 4 (Angptl4), also known as fasting-induced adiopogenic factor (FIAF), has recently been reported to influence bone metabolism. However, there have been few studies on regulatory factors other than hypoxia for Angptl4 in bone, and particularly in osteoblasts. Expression of interleukin-1β (IL-1β), a proinflammatory cytokine, is increased in serum or bone microenvironments in inflammatory bone diseases or estrogen deficient-conditions. The present study was conducted to determine whether Angptl4 expression in osteoblasts is affected by IL-1β and investigate its involvement in MAP kinase signaling pathways. Angptl4 RNA levels were increased by IL-1β treatment in murine MC3T3-E1 osteoblastic cells. Western blotting and immunofluorescent staining showed a corresponding increase in Angptl4 protein. IL-1β treatment of osteoblasts induced phosphorylation of mitogen-activated protein kinases (MAPKs) including extracellular regulated kinases (ERKs), p38, and c-Jun N-terminal kinase (JNK). Furthermore, SP600125, an inhibitor of JNK, significantly blocked the upregulation of Angptl4 by IL-1β. In contrast, treatment with an inhibitor of p38 MAP kinase (SB203580) or an ERK inhibitor (PD98059) produced responses similar to those seen with the DMSO control. Taken together, these results suggest that IL-1β increases Angptl4 expression through a mechanism dependent on the JNK-MAPK signaling pathway in MC3T3-E1 cells.