Plasma Levels of Asymmetric Dimethylarginine and Total Homocysteine in First Degree Relatives of Type 2 Diabetic Patients

Abstract

Objectives: Cardiovascular diseases are more common among first degree relatives of type 2 diabetic patients than healthy subjects without a family history of diabetes. Plasma asymmetric dimethylarginine (ADMA) and homocysteine (Hcy) levels are markers of endothelial dysfunction and cardiovascular disease. The objective of this study was to evaluate levels of ADMA, Hcy and their association with cardiovascular risk factors in first degree relatives of type 2 diabetic patients. Patients and Methods: The circulating ADMA and Hcy levels were measured in 15 first degree relatives of type 2 diabetic patients and 15 control subjects without a known family history of diabetes. Results: No statistically significant differences were found in plasma levels of ADMA and Hcy between the two groups (p>0.05). Plasma ADMA levels correlated significantly with waist circumference (p=0.02), fasting insulin levels (p=0.03), insulin resistance (p=0.01), total cholesterol (p=0.04) and HDL-cholesterol (p=0.03) levels in the first degree relatives of type 2 diabetic patients. Conclusion: These results suggest that plasma ADMA levels do not directly contribute to the development of endothelial dysfunction in first degree relatives of type 2 diabetic patients with cardiovascular risk factors. Turkish Başlık: Tip 2 Diyabetik Hastaların Birinci Derece Yakınlarında Total Homosistein ve Asimetrik Dimetilargininin Plazma Düzeyleri Anahtar Kelimeler: Tip 2 diabetes mellitus/genetik; N,N-dimetilarginin; homosistein Amaç: Tip 2 diyabetik hastaların birinci derece yakınlarında, ailesinde diyabet öyküsü olmayan sağlıklı olgulara göre kardiyovasküler hastalıklar daha sık görülmektedir. Asimetrik dimetilarginin (ADMA) ve homosistein (Hcy) plazma düzeyleri kardiyovasküler hastalıklar ve endotel disfonksiyonuyla ilişkili göstergelerdir. Bu çalışmada, tip 2 diyabetik hastaların birinci derece yakınlarında ADMA ve Hcy plazma düzeyleri ile bu göstergelerle kardiyovasküler risk faktörleri arasındaki ilişkilerin incelenmesi amaçlandı. Hastalar ve Yöntemler: Dolaşımdaki ADMA ve Hcy düzeyleri 15 tip 2 diyabet hastasının birinci derece yakınında ve ailesinde diyabet öyküsü olmayan 15 kontrol olgusunda ölçüldü. Bulgular: Her iki grup arasında ADMA ve Hcy plazma düzeyleri açısından anlamlı farklılık saptanmadı (p>0.05). Asimetrik dimetilarginin plazma düzeyi tip 2 diyabetik olguların birinci derece yakınlarında, bel çevresi (p=0.02), açlık insülin düzeyi (p=0.03), insülin direnci (p=0.01), total kolesterol (p=0.04) ve HDL kolesterol (p=0.03) ile ilişkiliydi. Sonuç: Bu sonuçlara göre, kardiyovasküler risk faktörlerine sahip olan tip 2 diyabetik olguların birinci derece yakınlarında, ADMA plazma düzeylerinin doğrudan endotel disfonksiyonunun gelişimine katkıda bulunmadığını düşünmekteyiz.

Keywords

• Diabetes mellitus, type 2/genetics; N,N-dimethylarginine; homocysteine

Tip 2 Diyabetik Hastaların Birinci Derece Yak›nlarında Total Homosistein ve Asimetrik Dimetilargininin Plazma Düzeyleri

Öz

Anahtar Kelimeler

• Tip 2 diabetes mellitus/genetik, N,N-dimetilarginin, homosistein.

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