Blood Levels of Leptin and Lymphocyte Subpopulations in Haflinger Mares on Winter and Summer Solstices

Abstract

Characterization of lymphocyte subpopulations provides important physiological information for understanding specific immune functions. Leptin, produced by the adipose tissue, plays a key role in both metabolic and immune system in many species including horse. The purpose of this study was to characterize blood levels of leptin and lymphocyte subpopulations of Haflinger mares on winter and summer solstices on June 21st and December 22nd, respectively . Additionally, we also determined possible correlation between leptin and lymphocyte subpopulations. After body weight and body condition score BCS were calculated, peripheral blood samples were collected from v. jugularis on winter n=7 and summer n=10 solstices. Leptin and lymphocyte subpopulations [CD2, CD3, CD4, CD8, CD19, and natural killer NK cells] were analyzed by radioimmunoassay RIA technique and flow cytometry, respectively. The mean leptin levels of Haflinger mares were 4.80±2.99 ng/mL. The mean percentage of CD2, CD3, CD4, CD8, CD19, NK cells, and CD4/CD8 ratio were determined as 53.8±7.3%, 50.6±7.2%, 33.8±8.2%, 16.8±4.5%, 46.2±7.3%, 3.2±1.4%, and 2.23±1.03 respectively. No statistical significance for leptin, lymphocyte subpopulations and CD4/CD8 ratio was found between winter and summer solstices P>0.05 . However, mean percentage of CD2 and NK cells on summer solstice and mean percentage of CD19 on winter solstice were slightly increased P=0.055 . No correlation between leptin and lymphocyte subpopulations was found P>0.05 . However, there was a significant positive correlation between leptin and BCS rs: 0.601, P=0.011 . Our results suggest that lymphocyte subpopulations could be altered regarding photoperiodic conditions but no effect of leptin was existed on these alterations in Haflinger mares.

Keywords

• Haflinger,Horse,Leptin,Lymphocyte subpopulations

Haflinger Kısraklarda Yaz ve Kış Gündönümlerindeki Kan Leptin ve Lenfosit Alt Tipleri Seviyeleri

Öz

Lenfosit alt tiplerinin belirlenmesi spesifik immun fonksiyonlar için önemli bilgiler sunmaktadır. Yağ dokusunda üretilen leptinin at türü de dahil pek çok türün metabolik ve immun sisteminde önemli rolü vardır. Bu çalışmanın amacı kış ve yaz gündönümlerinde Haflinger kısrakların kandaki lenfosit alt tipleri ile leptin miktarlarını belirlemektir. Ayrıca leptin ve lenfosit alt tipleri arasındaki muhtemel ilişki de değerlendirilmiştir. Vücut ağırlığı ve vücut kondisyon skorları VKS hesaplandıktan sonra kış n=7 ve yaz n=10 gündönümü zamanlarında v. jugularis’ten periferal kan örnekleri alındı. Leptin ve CD2, CD3, CD4, CD8, CD19 ve doğal öldürücü NK hücreleri kapsayan lenfosit alt tipleri sırasıyla radioimmunoassay RIA ve akım sitometri tekniği ile analiz edildi. Haflinger kısrakların ortalama leptin seviyeleri 4.80±2.99 ng/mL’di. CD2, CD3, CD4, CD8, CD19 ve NK hücrelerinin yüzde ortalamaları ile CD4/CD8 oranı sırasıyla 53.8±7.3, 50.6±7.2, 33.8±8.2, 16.8±4.5, 46.2±7.3, 3.2±1.4 ve 2.23±1.03 olarak belirlendi. Leptin seviyeleri, lenfosit alt tipleri ve CD4/CD8 oranı için kış ve yaz gündönümleri arasında istatistiksel önem bulunmadı P>0.05 . Fakat yaz gündönümünde CD2 ve NK hücre yüzdeleri, kış gündönümünde ise CD19 yüzdeleri hafif artış belirlendi P=0.055 . Leptin ile lenfosit alt tipleri arasında ilişki bulunmadı P>0.05 . Bununla birlikte leptin ile VKS arasında pozitif bir ilişki vardı rs: 0.601, P=0.011 . Sonuçlar Haflinger kısraklarda lenfosit alt tiplerinin mevsime bağlı değişimler gösterebileceğini fakat leptinin bu değişimlerde etkili olmadığına işaret etmektedir.

Anahtar Kelimeler

• At,Haflinger,Lenfosit alt tipleri,Leptin

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