Long-term melatonin supplementation does not recover the impairment of natural killer cell activity and lymphocyte proliferation in aging mice.
In this study we evaluated the effect of long-term melatonin (MEL) treatment on the cytotoxic activity and number of natural killer (NK) cells and the proliferative response of spleen lymphocytes to phytohemagglutinin (PHA) or interleukin-2 (IL-2) in old mice. Seventeen-eighteen month-old Balb/c mice were supplemented with MEL (40-50 microg/day/mouse) and sacrificed after eight months. The MEL supplementation was unable to recover the low levels of both endogenous and IL-2-induced NK cell activity found in old untreated mice. Also the NK cell number was unaffected by MEL treatment. The spleen lymphocyte proliferative response to both PHA and IL-2 was not different in old MEL-treated compared to old untreated mice. These results indicate that long-term MEL supplementation does not recover the age-related deterioration of NK cell activity and lymphocyte proliferative capacity.
Provinciali
M
M
Immunology Center, Gerontology Research Department, INRCA, Ancona, Italy. m.provinciali@inrca.it
Di Stefano
G
G
Bulian
D
D
Stronati
S
S
Fabris
N
N
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000375:Aging / Q000187:drug effects* / Q000276:immunology*; D000818:Animals; D002452:Cell Count / Q000187:drug effects; D007376:Interleukin-2 / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010835:Phytohemagglutinins / Q000494:pharmacology; D013154:Spleen / Q000166:cytology; D013997:Time Factors
D000276:Adjuvants, Immunologic; D007376:Interleukin-2; D010835:Phytohemagglutinins; D008550:Melatonin