Modulation of granulocyte functions by peptide YY in the rat: age-related differences in Y receptors expression and plasma dipeptidyl peptidase 4 activity.
It has been acknowledged that aging exerts detrimental effects on cells of the innate immune system and that neuropeptides, including neuropeptide Y (NPY) and NPY-related peptides fine-tune the activity of these cells through a receptor specific mechanism. The present study investigated the age-dependent potential of peptide YY (PYY) to modulate different granulocyte functions. The PYY reduced the carrageenan-elicited granulocyte accumulation into the air-pouch of aged (24 months) rats, and markedly decreased the phagocytosis of zymosan, as well as the H(2)O(2) production, when applied in vivo (20 microg/air-pouch). The anti-inflammatory effect of PYY was less prominent in adult (8 months) and young (3 months) rats. However, the proportions of granulocytes expressing Y1, Y2 and Y5 receptor subtypes were significantly lower in both aged and young rats when compared to adult rats. Furthermore, the aging was found to be associated with the diminished dipeptidyl peptidase 4 (DP4, an enzyme converting the NPY and PYY to Y2/Y5 receptor selective agonists) activity in plasma. In conclusion, the diverse age-related anti-inflammatory effect of PYY in rats originates from different expression levels of Y1, Y2, and Y5 receptor subtypes in addition to different plasma DP4 activity.
Dimitrijević
Mirjana
M
Immunology Research Center Branislav Janković, Institute of Virology, Vaccines and Sera, Torlak, Vojvode Stepe 458, 11221 Belgrade, Serbia. miradim@sezampro.rs
Stanojević
Stanislava
S
Mitić
Katarina
K
Kustrimović
Natasa
N
Vujić
Vesna
V
Miletić
Tatjana
T
Kovacević-Jovanović
Vesna
V
D000375:Aging / Q000097:blood / Q000276:immunology*; D000818:Animals; D002351:Carrageenan / Q000494:pharmacology; D018819:Dipeptidyl Peptidase 4 / Q000097:blood / Q000276:immunology*; D006098:Granulocytes / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D008297:Male; D009478:Neuropeptide Y / Q000097:blood / Q000276:immunology*; D010587:Phagocytosis / Q000187:drug effects / Q000276:immunology*; D051381:Rats; D017476:Receptors, Neuropeptide Y / Q000276:immunology* / Q000378:metabolism; D015054:Zymosan / Q000494:pharmacology
D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; D002351:Carrageenan; D015054:Zymosan; D018819:Dipeptidyl Peptidase 4