The Relationship Between Proinflammatory Cytokine Levels and Fibrinolytic System in Obese Patients

Abstract

Objectives: The aim of this study was to investigate the relationship between proinflammatory cytokines (TNF-α and IL-6), and fibrinolytic system parameters (t-PA, and PAI-1) and insulin resistance in obese individuals. Patients and Methods: The study included 54 obese subjects (BMI ≥30 kg/m2; 41 females, 13 males; mean age 33.5 years) and 30 non-obese healthy individuals (BMI <25 kg/m2; 19 females, 11 males; mean age 22.3 years). Fibrinogen levels were measured by the coagulometric method and the measurements of TNF-α, IL-6, t-PA and PAI-1 were carried out by the ELISA method. Results: Compared with non-obese subjects, obese individuals had significantly higher fibrinogen (p<0.01), PAI-1 (p<0.001), TNF-α (p<0.01), and IL-6 (p<0.001) levels, and significantly lower t-PA level (p<0.001) and t-PA/PAI-1 ratio (p<0.001). We also found an inverse relationship between TNF-α and t-PA levels (p=0.007) and t-PA/PAI-1 ratio (p=0.016) in obese individuals. The presence or absence of insulin resistance did not affect proinflammatory cytokines and fibrinolytic system parameters in obese individuals. Conclusion: Our findings indicate increased inflammatory cytokine levels especially in TNF-α level, and decreased fibrinolysis in obese individuals. These changes may contribute to atherosclerotic process independent from insulin resistance in obesity. Turkish Başlık: Obez Hastalarda Proinflamatuvar Sitokinler ile Fibrinolitik Sistem Arasındaki İlişki Anahtar Kelimeler: Sitokinler; fibrinoliz; insülin direnci; obezite/komplikasyon Amaç: Obez kişilerde proinflamatuar sitokinlerden TNF-α ve IL-6, fibrinolitik sistem parametrelerinden t-PA ve PAI-1 ve insülin direnci arasındaki ilişki araştırıldı. Hastalar ve Yöntemler: Çalışmaya obez (VKİ ≥30 kg/m2) olarak değerlendirilen 54 kişi (41 kadın, 13 erkek; ort. yaş 33.5) ve obezite sorunu olmayan (VKİ <25 kg/m2) 30 kişi (19 kadın, 11 erkek; ort. yaş 22.3) alındı. Fibrinojen düzeyleri koagülometrik olarak ve TNF-α, IL-6, t-PA, PAI-1 düzeyleri ELISA yöntemiyle ölçüldü. Bulgular: Kontrol grubuyla karşılaştırıldığında, obez kişilerde fibrinojen (p<0.01), PAI-1 (p<0.001), TNF-α (p<0.01) ve IL-6 düzeyleri (p<0.001) anlamlı derecede yüksek, t-PA düzeyi (p<0.001) ve t-PA/PAI-1 oranı (p<0.001) anlamlı derecede düşük bulundu. Obezlerde TNF-α ile t-PA (p=0.007) ve t-PA/PAI-1 oranı (p=0.016) arasında ters ilişki saptandı. İnsülin direnci olan ve olmayan obez kişilerde parametreler arasında fark yoktu. Sonuç: Obezitede adipoz dokudan salgılanan özellikle TNF-α gibi inflamatuar sitokinlerin artması fibrinolizde azalmaya yol açar. Obez kişilerde görülen bu değişiklikler, insülin direncinden bağımsız olarak ateroskleroza neden olabilir.

Keywords

• Cytokines; fibrinolysis; insulin resistance; obesity/complications

Obez Hastalarda Proinflamatuvar Sitokinler ile Fibrinolitik Sistem Arasındaki İlişki

Öz

Amaç: Obez kişilerde proinflamatuar sitokinlerden TNF-a ve IL-6, fibrinolitik sistem parametrelerinden t-PA ve PAI-1 ve insülin direnci arasındaki ilişki araştırıldı. Hastalar ve Yöntemler: Çalışmaya obez (VKİ ≥30 kg/m2) olarak değerlendirilen 54 kişi (41 kadın, 13 erkek; ort. yaş 33.5) ve obezite sorunu olmayan (VKİ < 25 kg/m2) 30 kişi (19 kadın, 11 erkek; ort. yaş 22.3) alındı. Fibrinojen düzeyleri koagülometrik olarak ve TNF-a, IL-6, t-PA, PAI-1 düzeyleri ELISA yöntemiyle ölçüldü. Bulgular: Kontrol grubuyla karşılaştırıldığında, obez kişilerde fibrinojen (p < 0.01), PAI-1 (p < 0.001), TNF-a (p < 0.01) ve IL-6 düzeyleri (p < 0.001) anlamlı derecede yüksek, t-PA düzeyi (p < 0.001) ve t-PA/PAI-1 oranı (p < 0.001) anlamlı derecede düşük bulundu. Obezlerde TNF-a ile t-PA (p=0.007) ve t-PA/PAI-1 oranı (p=0.016) arasında ters ilişki saptandı. İnsülin direnci olan ve olmayan obez kişilerde parametreler arasında fark yoktu. Sonuç: Obezitede adipoz dokudan salgılanan özellikle TNF-a gibi inflamatuar sitokinlerin artması fibrinolizde azalmaya yol açar. Obez kişilerde görülen bu değişiklikler, insülin direncinden bağımsız olarak ateroskleroza neden olabilir.

Anahtar Kelimeler

• Sitokinler, fibrinoliz, insülin direnci, obezite/komplikasyon

Kaynakça

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