THIOL-DISULFIDE HOMEOSTASIS IN MYASTHENIA GRAVIS

Öz

Objective: Neuromuscular junction disorders (NJD), characterized by a dysfunction in neuromuscular transmission, may be associated with oxidative stress. This study aimed to evaluate the role of thiol-disulfide homeostasis as an index of oxidative stress in adult patients with NJD (i.e., myasthenia gravis) compared to healthy controls, considering its potential as a biomarker and therapeutic target. Materials and Methods: This study included 46 patients with myasthenia gravis and 46 age- and gender-matched healthy controls. Blood samples were collected and analyzed for thiol-disulfide homeostasis parameters, total antioxidant status (TAS), and ischemia-modified albumin (IMA) using spectrophotometric and colorimetric methods. Statistical analysis was conducted using SPSS to compare the groups and examine correlations between oxidative and antioxidant markers. Results: Patients showed significantly lower levels of native thiol, total thiol, and TAS, and higher levels of disulfide, disulfide/native thiol percentage ratio, and IMA compared to controls (p<0.05 for all). These findings indicate increased oxidative stress and disrupted antioxidant defense in patients with myasthenia gravis. There were also significant correlations between decreased antioxidant parameters and increased oxidative stress markers. Conclusion: This study confirms that thiol-disulfide homeostasis is significantly altered in patients with myasthenia gravis, highlighting its potential role as a biomarker for disease pathogenesis and a target for therapeutic intervention. Future research could expand on these findings to develop targeted therapies aimed at restoring redox balance in patients with NJD.

Anahtar Kelimeler

• thiol
• disulfide
• homeostasis
• neuromuscular
• myasthenia gravis

Etik Beyan

This study was approved by the ethics committee of Ankara Bilkent City Hospital (Approval Code: E2-23-4412).

MYASTENİA GRAVİSTE TİYOL-DİSÜLFİT HOMEOSTAZİSİ

Öz

Amaç: Nöromüsküler iletimde bir işlev bozukluğu ile karakterize olan nöromüsküler kavşak bozuklukları (NKB), oksidatif stresle ilişkili olabilir. Bu çalışma, NKB'li (myastenia gravis) yetişkin hastalarda oksidatif stresin bir endeksi olarak tiyol-disülfit homeostazının rolünü, bir biyobelirteç ve terapötik hedef olarak potansiyelini göz önünde bulundurarak sağlıklı kontrollerle karşılaştırmayı amaçlamıştır. Gereç ve Yöntemler: Bu çalışmaya myastenia gravis tanılı 46 hasta ve yaş ve cinsiyet açısından eşleştirilmiş 46 sağlıklı kontrol dahil edildi. Kan örnekleri toplandı ve tiyol-disülfid homeostazisi parametreleri, toplam antioksidan durumu (TAS) ve iskemi ile modifiye edilmiş albümin (IMA) açısından spektrofotometrik ve kolorimetrik yöntemler kullanılarak analiz edildi. Grupları karşılaştırmak ve oksidatif ve antioksidan belirteçler arasındaki korelasyonları incelemek için SPSS kullanılarak istatistiksel analiz yapıldı. Bulgular: Hastalar, kontrollere kıyasla önemli ölçüde daha düşük doğal tiyol, toplam tiyol ve TAS seviyeleri ve daha yüksek disülfit, disülfit/doğal tiyol yüzde oranı ve IMA seviyeleri gösterdi (tümü için p<0.05). Bu bulgular myastenia gravis tanısı olan hastalarda oksidatif stresin arttığını ve antioksidan savunmanın bozulduğunu göstermektedir. Azalan antioksidan parametreler ile artan oksidatif stres belirteçleri arasında da anlamlı korelasyonlar vardı. Sonuç: Bu çalışma, myastenia gravis tanısı olan hastalarda tiyol-disülfit homeostazisinin önemli ölçüde değiştiğini doğrulayarak, bunun hastalık patogenezi için bir biyobelirteç ve terapötik müdahale için bir hedef olarak potansiyel rolünü vurgulamaktadır. NKB’li hastalarda redoks dengesini yeniden sağlamayı amaçlayan hedefe yönelik tedaviler geliştirmek için bu bulgular üzerinde daha fazla araştırma yapılabilir.

Anahtar Kelimeler

• tiyol
• disülfit
• homeostazi
• nöromusküler
• myastenia gravis

Kaynakça

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