The effect of testosterone supplementation on morphometry and VEGF expression level of thoracic aorta in aged mice

Abstract

The aim of this study was to determine the effects of the testosterone hormone level on morphometry and vascular endothelial growth factor (VEGF) expression level of thoracic aorta of aged mice using histological and molecular techniques. A total of 30 aged mice (15 males and 15 females) were enrolled in 3 study groups: sham operation group (Control), gonadectomy group (G) and gonadectomy and testosterone supplementation group (GTS). Serum testosterone levels were measured by ELISA. Intima and media thickness and inner diameter of thoracic aorta were measured by morphometric investigation. The levels of the angiogenic factor, VEGF (vascular endothelial growth factor) mRNA in thoracic aorta were determined by RT-PCR. Although the alterations in the level of testosterone had no significant effects on intima or media thickness of the male thoracic aorta, in female, there was a significant increase (p<0.01) on intimal thickness in thoracic aorta following gonadectomy and hormone supplementation. The largest inner diameter was in testosterone supplementation groups of both sexes. Gonadectomie operation caused decrease in VEGF mRNA levels of thoracic aorta in male (p<0.05) and female mice. Interestingly, testosterone replacement caused an important decrease (p<0.01) in the expression of VEGF of aorta in female whereas resulted with an increase in male. Present results showed that testosterone hormone had different angiogenic effects on thoracic aorta in male and female aged mice. Additionally, gonadectomie operation in aged mice caused decrease in the level of VEGF mRNA levels in both sexes

Keywords

• Aged
• mice
• testosterone
• thoracic aorta
• VEGF

The effect of testosterone supplementation on morphometry and VEGF expression level of thoracic aorta in aged mice

Abstract

Çalışmanın amacı, yaşlı farelerde testosteron hormonu seviyesinin aorta thoracica’daki anjiogenik etkisini ve vaskülo endoteliyal büyüme faktörünün (VEGF) ekspresyon düzeyini histolojik ve moleküler yöntemlerle belirlemektir. Çalışmada 30 adet yaşlı fare (15 erkek ve 15 dişi) üç farklı gruba ayrıldı. Bu gruplar; yalancı gonadektomi operasyonu yapılan kontrol grubu, gonadektomi operasyonu yapılan (G) grup ve hem gonadektomi hem de testosteron takviyesi yapılan (GTS) gruptur. Hayvanların kanındaki testosteron seviyesi ELISA testi ile ölçüldü. Aorta thoracica’nın intima ve media kalınlıkları ile iç çapı morfometrik incelemelerle belirlendi. Aorta thoracica’daki anjiogenik faktörlerden biri olan VEGF mRNA miktarı ise RT-PCR tekniği ile tespit edildi. Testosteron seviyesindeki değişimlerin erkeklerde aorta thoracica’nın intima ve media kalınlıklarında önemli bir etkisinin olmadığı saptandı. Dişilerde ise gonadektomi operasyonundan sonra yapılan hormon takviyesinin intima kalınlığında bir artışa (p<0.01) neden olduğu belirlendi. Aorta thoracica’nın iç çapı en geniş olarak her iki cinste de GTS grubunda belirlendi. Gonadektomi operasyonunun VEGF mRNA miktarı üzerinde erkek (p<0.05) ve dişilerde bir azalmaya neden olduğu saptandı. Testosteron takviyesi aorta thoracica’daki VEGF mRNA ekspresyon seviyesinde dişilerde azalmaya (p<0.01) neden olurken, erkeklerde artışa neden olmaktadır. Elde edilen sonuçlara göre, testosteron hormonunun yaşlı erkek ve dişi farelerde farklı anjiyogenik etkiye sahip olduğu belirlendi. Ayrıca her iki cinsiyette de gonadektomi operasyonunun VEGF’nin mRNA seviyesinde azalmaya neden olduğu saptandı

Keywords

• Aorta thoracica
• fare
• testosteron
• VEGF
• yaşlılık

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