Yüksek Yağlı Diyet ve Fibronektin Tip III Alan İçeren Protein 5 mRNA Ekspresyonu Arasındaki İlişki

Amaç: Hem kahverengi yağ dokusunda hem de kas dokusunda fibronektin tip III alan içeren protein 5 (FNDC5) bol bulunur. FNDC5 ve FNDC5'in fragmenti olan irisinin çeşitli etkilerinden dolayı obezite ile ilişkili metabolik hastalıkların tedavisinde terapötik molekül olarak kullanılabileceği ifade edilmektedir. Membran proteini olan FNDC5 ve irisin yakın zamanda keşfedildiği için literatürde henüz sınırlı sayıda çalışma bulunmaktadır. Bu çalışmanın amacı kas ve kahverengi yağ dokusunda yüksek yağlı diyet ve metabolik hastalıklarla ilişkili FNDC5 mRNA ekspresyonu arasındaki ilişkiyi incelemektir.Gereç ve Yöntemler: Çalışmada 18 adet 1,5-2 aylık erkek Sprague-Dawley sıçan her birinde 6 sıçan olacak şekilde rastgele üç gruba ayrıldı. Sıçanlar gruplarına özgü yemle 85 gün beslendi. Beslenme sürecinin bitiminde kas ve kahverengi yağ dokuları toplandı ve bu dokularda FNDC5 mRNA ekspresyon ölçümleri yapıldı.Bulgular: Kontrol grubu ile obez grubun FNDC5 mRNA seviyeleri karşılaştırıldığında, kahverengi yağ dokusunda bu seviye obez grupta kontrol grubundakinden daha yüksekti (p=0,016). Yine aynı dokuda obez grubun FNDC5 mRNA seviyesinin antioksidan grubununkinden daha yüksek olduğu tespit edildi (p=0,010). Kas dokusunda ise antioksidan grubunda kontrol grubuna göre daha düşük FNDC5 mRNA ekspresyonu ölçüldü (p=0.006).Tartışma ve Sonuç: Çalışmamızdan yüksek yağlı diyetin kahverengi yağ dokusundaki FNDC5 mRNA ekspresyonunu değiştirdiği fakat kas dokusunda değiştirmediği, bu nedenle yüksek yağlı diyetin kahverengi yağ dokusunda FNDC5 mRNA ekspresyonunun düzenlenmesinde etkili olabileceği anlaşılmaktadır.

The Relationship between High-Fat Diet and Fibronectin Type-III Domain- Containing Protein 5 mRNA Expression

Aim: Fibronectin type-III domain-containing protein 5 (FNDC5) is abundant in both muscle and brown adipose tissues. It has been suggested that due to their various effects FNDC5 and irisin (fragment of FNDC5) might be used as a therapeutic molecule in the treatment of obesity-related metabolic diseases. Due to the recent discovery of irisin/FNDC5, there are yet a limited number of studies in the literature. In this study, we aimed to investigate the relationship between a high-fat diet and the FNDC5 mRNA expression in the muscle and brown adipose tissues, associated with metabolic diseases.Materials and Methods: Eighteen male Sprague-Dawley rats aged 1.5 to 2 months were randomized into three groups of six rats each. Each group was fed its group-specific diet for 85 days. At the end of the feeding period, measurements of FNDC5 mRNA expression were performed in collected specimens of muscle and brown adipose tissues.Results: It was observed that the FNDC5 mRNA levels in the brown adipose tissue were higher for the obese group in comparison to the control group (p=0.016) and to the antioxidant group (p=0.010), relatively. In the muscle tissue, however, FNDC5 mRNA expression levels were measured to be lower, compared to the controls (p=0.006).Discussion and Conclusion: Our study indicated that a high-fat diet caused a change in FNDC5 mRNA expression levels in the brown adipose tissue, but not in the muscle tissue, and thus might help regulate FNDC5 mRNA expression in the brown adipose tissue.

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