Effects of zinc on programmed cell death of Musca domestica and Drosophila melanogaster blood cells.
Programmed cell death (PCD) and phagocytotic activity of immune cells play a pivotal role in insect development. We examined the influence of Zn(2+), an important element to fundamental biological processes, on phagocytosis and apoptosis of hemocytes in two fly species: Musca domestica and Drosophila melanogaster. Hemocytes were isolated from the third instar larvae of both species and treated for 3h with zinc chloride solutions, containing 0.35 mM or 1.7 mM of Zn(2+), and untreated as control. Phagocytotic activity of hemocytes was examined by flow cytometry after adding latex fluorescent beads to the medium, while apoptosis was evaluated by application of annexinV-FITC and pan-caspase-FITC inhibitor. Mitochondrial viability was determined by measuring resazurin absorbancy in the cell medium. The obtained results showed that Zn(2+) increases phagocytosis and affects PCD of both species hemocytes but each in a different way. Zinc decreases fraction of annexin-positive hemocytes in M. domestica but increases it in D. melanogaster. The pan-caspase analysis revealed low and high activity of caspases in hemocytes of M. domestica and D. melanogaster, respectively. Zn(2+) also decreased the viability of hemocyte mitochondria but only in D. melanogaster. It suggests that flies use different pathways of PCD, or that Zn plays a different role in this process in M. domestica than in D. melanogaster.
Filipiak
Marta
M
Department of Cytology and Histology, Institute of Zoology, Jagiellonian University, Ingardena 6, 30-060 Kraków, Poland.
Bilska
Ewelina
E
Tylko
Grzegorz
G
Pyza
Elzbieta
E
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D002712:Chlorides / Q000494:pharmacology*; D004331:Drosophila melanogaster / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D005260:Female; D006434:Hemocytes / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology; D006793:Houseflies / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D019476:Insect Proteins / Q000378:metabolism; D008297:Male; D010587:Phagocytosis / Q000187:drug effects; D017967:Zinc Compounds / Q000494:pharmacology*
D002712:Chlorides; D019476:Insect Proteins; D017967:Zinc Compounds; C016837:zinc chloride; D020169:Caspases