An investigation on the effect of leptin on rat kidney tissue

Öz

Aim: increasing day by day obesity, one of the preventable health problems. Obese individual increases the risk of renal disease one and a half times more compared to the non-obese individuals. Leptin is a type of adipokinin hormone which is released from adipose tissue cells in proportion to the amount of adipose tissue. It is known that leptin leads to a rise in reactive oxygen radicals in the tissue. This study aimed at investigating if leptin affects renal tissue by giving leptin to the rats. Material–Method: The total of 16 Wistar albino rats (weights ranged from 250g-300g) in the study were randomly divided into groups of eight in two different cages. The first group was the Control group (intraperitoneally = i.p. 0.9% normal saline) and the second group was the leptin group (ip 0,1 mg/kg leptin). The subjects, which were given leptin i.p. for 7 days, and the ones in the control group, which were given 0.9% normal saline to trigger the same stress, were sacrificed and their kidneys were taken out for examination. The kidneys were fixed with 10% neutral form was formaldehide to routine histological procedure. The sections stained with hematoxylin-eosin = H-E were analyzed under light microscopy. Results: The sections in the control group were found to be normal hystologically. Compared to these, the renal tissue samples in the leptin group were determined to have mononuclear cell infiltration in the cortex, tubular dilatation in the medulla, degeneration and hemorrhagic areas, vacuolar degeneration in glomeruli and dilation in proximal and distal tubular. Discussion: Revealing the effects of leptin on renal damage is important for avoiding harmful effects of obesity through hormonal and behavioral arrangements. This study suggested that leptin could cause renal pathologies by damaging renal tissue. We are of the opinion that being able to explain renal damage etiology exactly will be useful to differential diagnosis and treatments

Anahtar Kelimeler

• Leptin
• kidney
• obesity
• renal damage
• adipokines

Ratların böbrek histomorfolojisi üzerine leptin etkisinin araştırılması

Öz

Özet Amaç: Günümüzde gittikçe artan obezite, önlenebilir sağlık sorunlarından biridir. Obez bireylerde böbrek hastalığı riski obez olmayan bireylere göre yaklaşık 1.5 kat artmaktadır. Leptin yağ dokusu miktarıyla orantılı olarak yağ dokusu hücrelerinden salgılanan bir adipokindir.ve dokuda serbest oksijen radikallerinin artışına yol açtığı bilinmektedir. Bu çalışmada ratlara leptin vererek, hiperleptineminin böbrek histomorfolojisi üzerine etkisinin araştırılması amaçlandı. Gereç ve Yöntem: Çalışmamızda ağırlıkları 250 gr ile 350 gr arasında değişen 16 adet Wistar albino rat kullanıldı. Ratlar, her kafeste rastgele 8 hayvan bulunan 2 gruba ayrıldı. 1.Grup; Kontrol (intraperitoneal = i.p. Serum Fizyolojik = SF) 7 gün, 2. Grup Leptin (i.p. 0,1 mg/kg leptin) 7 gün, olacak şekilde planlandı. 7 gün boyunca i.p. olarak leptin verilen hayvanlar ve aynı stresi oluşturmak amacıyla SF verilen kontrol grubundaki hayvanlar deney sonunda, anestezi altında sakrifiye edildi ve tüm ratların her iki böbreği de incelenmek üzere çıkarıldı. %10 nötral formalinde fikse edilen böbreklere rutin histolojik prosedür uygulandı. Hematoksilen-Eozin = H-E ile boyanan kesitler ışık mikroskobisi altında değerlendirildi. Bulgular: Kontrol grubuna ait kesitlerde böbrek dokularının normal histolojik yapısında olduğu gözlendi. Kontrol grubuyla kıyaslandığında leptin grubuna ait böbrek dokusu örneklerinde, kortekste mononükleer hücre infiltrasyonu, medullada tübüler dilatasyon, dejenerasyon ve hemorajik alanlar, glomerüllerde vakuoler dejenerasyon, proksimal ve distal tübülerde dilatasyon izlendi. Tartışma: Leptin ve böbrek hasarı arasındaki ilişkinin gösterilmesi hormonal ve davranışsal düzenlemelerle obezitenin zararlı etkilerinden korunmak için önemlidir. Bu araştırmanın sonucunda; leptinin böbrek dokusunu olumsuz etkilediğini ve böbrek dokusunda hasar meydana getirdiğini söyleyebiliriz.. Bize göre, obez bireylerde görülen böbrek hasarı etyolojisi açıklanırken leptin faktörüde gözönünde bulundurulmalıdır. Anahtar kelimeler: Leptin, böbrek, obezite, böbrek hasarı An investigation on the effect of leptin on histomorphology of rat kidney Cennet Ak 1, Dilek Bayram 2, Ilkay Armagan 2, A. Cihangir Uguz 3 1 Department of Physiology, School of Medicine, Suleyman Demirel University, Isparta, Turkey 2 Department of Histology and Embryology, School of Medicine, Suleyman Demirel University, Isparta, Turkey 3Department of Biophysics, School of Medicine, Süleyman Demirel University, Isparta, Turkey. Abstract Aim: increasing day by day obesity, one of the preventable health problems. Obese individual increases the risk of renal disease one and a half times more compared to the non-obese individuals. Leptin is a type of adipokinin hormone which is released from adipose tissue cells in proportion to the amount of adipose tissue. It is known that leptin leads to a rise in reactive oxygen radicals in the tissue. This study aimed at investigating if leptin affects renal tissue by giving leptin to the rats. Material – Method: The total of 16 Wistar albino rats (weights ranged from 250g-300g) in the study were randomly divided into groups of eight in two different cages. The first group was the Control group (intraperitoneally = i.p. 0.9% normal saline) and the second group was the leptin group (ip 0,1 mg/kg leptin). The subjects, which were given leptin i.p. for 7 days, and the ones in the control group, which were given 0.9% normal saline to trigger the same stress, were sacrificed and their kidneys were taken out for examination. The kidneys were fixed with 10% neutral form was formaldehide to routine histological procedure. The sections stained with hematoxylin-eosin = H-E were analyzed under light microscopy. Results: The sections in the control group were found to be normal hystologically. Compared to these, the renal tissue samples in the leptin group were determined to have mononuclear cell infiltration in the cortex, tubular dilatation in the medulla, degeneration and hemorrhagic areas, vacuolar degeneration in glomeruli and dilation in proximal and distal tubular. Discussion: Revealing the effects of leptin on renal damage is important for avoiding harmful effects of obesity through hormonal and behavioral arrangements. This study suggested that leptin could cause renal pathologies by damaging renal tissue. We are of the opinion that being able to explain renal damage etiology exactly will be useful to differential diagnosis and treatments. Keywords: Leptin, kidney, obesity, renal damage

Anahtar Kelimeler

• Leptin
• böbrek
• obezite
• böbrek hasarı
• adipokin

Kaynakça

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