Linked Life Data

12606383

Source:http://linkedlifedata.com/resource/pubmed/id/12606383

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-6-23
pubmed:abstractText
Seasonal fluctuations in immune status have been documented for avian and mammalian populations. During the late summer and early fall, immune function is bolstered to help animals cope with the more physiologically demanding winter. The environmental cue for these seasonal changes is apparently decreasing photoperiod. In the present study, we determined the potential role of leptin in mediating the effect of photoperiod on cell-mediated immune responses in male mice. Leptin-deficient (ob/ob) and littermate control mice were housed for 10 wk in either a short (8L:16D) or a long (16L:8D) photoperiod beginning at 6 wk of age. After the mice were killed, immune and reproductive organs were weighed and splenocytes isolated. The proliferative and cytokine responses (interleukin [IL]-2 and IL-4) of splenocytes to the T-cell mitogen, concanavalin A (Con A; 0-40 microg/ml), were determined. Body weights were elevated and both testes and seminal vesicle weights subnormal in ob/ob mice (by ANOVA, main effect of leptin deficiency), but thymuses and spleens were of normal size. Serum leptin levels were at minimum detection limits in ob/ob mice, but leptin levels in control mice housed at 8L:16D were higher than in control mice housed at 16L:8D. The proliferative response of splenocytes from ob/ob mice to Con A was subnormal (by ANOVA, main effect of leptin deficiency), but photoperiod had no effect on this response. Production of IL-2 in splenocytes of ob/ob mice was subnormal (by ANOVA, main effect of leptin deficiency) irrespective of photoperiod, but cells from mice housed at 8L:16D (by ANOVA, main effect of photoperiod) produced more IL-2 than cells from animals housed at 16L:8D. In contrast, a leptin deficiency did not alter IL-4 production, but cells from animals (ob/ob and controls) housed at 16L:8D produced less IL-4 than cells from animals housed at 8L:16D (by ANOVA, main effect of photoperiod). The present study suggests that both photoperiod and leptin have mutually independent effects on the proliferation of lymphocytes and cytokine production profiles. The data do not provide definitive support for the hypothesis that photoperiod-induced changes in leptin secretion mediate the effects of season on immune status.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
69
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
30-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Does leptin mediate the effect of photoperiod on immune function in mice?
pubmed:affiliation
Cooperative Reproductive Science Research Center, and Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia 30310, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.