Ghrelin Levels in Patients with Rickets

Abstract

Rickets is a common metabolic bone disease in infants. The predominant cause of rickets is vitamin D deficiency. Vitamin D is required for bone formation. The role of ghrelin in bone metabolism is unclear, but it may have an indirect effect. There are also reports in the literature suggesting that ghrelin acts directly on osteoblasts as a positive regulator. To evaluate the relationship between ghrelin levels and the development of rickets. We evaluated the relationship between serum/ saliva ghrelin levels and rickets in a cohort of 10 patients aged 6-24 months with nutritional rickets and completely healthy 14 children. Plasma ghrelin levels were measured using a commercial radioimmunoassay kit. The saliva ghrelin measurements were performed using a Human-ghrelin- radioimmunoassay-sensitive kit. Ghrelin levels in blood and saliva were found significantly lower in the rickets group compared to the healthy subjects in this study. Findings of this study shows that there is a relationship between ghrelin and the development of rickets. Decreased ghrelin levels may have caused to poor infant appetite and impaired nutritional status. Furthermore the absence of ghrelin\'s calciotropic effects may have contributed to the development of rickets. Detailed studies with larger series are warranted to support these findings.

Keywords

• Ghrelin, rickets, vitamin D

Ghrelin Levels in Patients with Rickets

Öz

Rikets erken çocukluk döneminde sık rastlanan metabolik bir kemik hastalığıdır. Başlıca sebebi vitamin D eksikliğidir. Vitamin D kemiklerin oluşumu için gereklidir. Kemik metabolizmasında ghrelinin rolü açık değildir ancak dolaylı yoldan etkisi olabilir. Ayrıca literatürde ghrelinin osteoblastlar üzerine doğrudan pozitif bir düzenleyici olarak etki ettiğine dair yayınlar vardır. Ghrelin düzeyleri ile rikets gelişimi arasındaki ilişkiyi incelemek. Nutrisyonel riketsi olan, yaşları 6- 24 ay arasında değişen 10 hasta ve 14 sağlıklı çocukta serum/ tükürük ghrelin düzeyleri ile rikets arasındaki ilişkiyi inceledik. Plazma ghrelin düzeyleri ticari bir radioimmunoassay kiti kullanılarak ölçüldü. Tükürük ghrelini ölçümleri, İnsan ghrelini- radioimmunoassay- duyarlı kit kullanılarak yapıldı. Kan ve tükürük ghrelin düzeyleri, rikets grubunda çalışmadaki sağlıklı kişilere göre anlamlı olarak düşük bulundu. Çalışmanın sonuçları rikets gelişimi ile ghrelin arasında bir ilişkinin var olduğunu göstermektedir. Azalmış ghrelin düzeyleri, infantın iştahının ve nutrisyonel durumunun olumsuz yönde etkilenmesine hem de ghrelinin kemik dokusu üzerindeki kalsiyotropik etkisinin ortadan kalkmasına sebebiyet vermiş olabilir. Ancak daha fazla olguyu içeren ayrıntılı çalışmalarla bunun desteklenmesi gerekir

Anahtar Kelimeler

• Ghrelin, rikets, vitamin D

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