Journals / Turkish Journal of Hematology / 2014 / Cilt: 31 - Sayı: 2

The Functional Significance of the Rho/Rho-Kinase Pathway in Human Erythrocytes

İnsan Eritrositlerinde Rho/Rho-Kinaz Yolağının Fonksiyonel Önemi

Pages
168–174
DOI
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Conclusion:Our findings may indicate that the Rho/Rho-kinase pathway could contribute to the regulation of deformability of human erythrocytes.

📌 3 Key Takeaways

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Objective & Hypothesis:Objective: Erythrocyte deformability, which can be influenced by various intracellular signaling mechanisms, such as nitric oxide, cAMP, cGMP, and protein kinases, is the most important physiological factor providing the blood flow in microcirculation.
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Key Findings & Data:Materials and Methods:RhoA and ROCK-2 proteins were studied by western blotting.
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Conclusion & Impact:Conclusion:Our findings may indicate that the Rho/Rho-kinase pathway could contribute to the regulation of deformability of human erythrocytes.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Domain Parameters

Abstract

Objective: Erythrocyte deformability, which can be influenced by various intracellular signaling mechanisms, such as nitric oxide, cAMP, cGMP, and protein kinases, is the most important physiological factor providing the blood flow in microcirculation. However, the functional significance of the Rho/Rho-kinase pathway, which contributes cell shape changes and the reorganization of the actin cytoskeleton, has yet to be explored in erythrocytes. Therefore, we examined the influence of several activators and inhibitors of Rho/Rho-kinase signaling on human erythrocyte deformability. Materials and Methods:RhoA and ROCK-2 proteins were studied by western blotting. Influences of 2 Rho-kinase inhibitors, fasudil and y-27632 (both 10-7 to 10-4 M), on erythrocyte deformability was determined by ektacytometer at various shear stresses (0-30 Pa) in the presence or absence of a known Rho activator, lysophosphatidic acid (LPA, 10-5 to 5x10-5 M, 1-15 min). Results:LPA incubation reduced deformability with concomitant RhoA-GTP inhibition. y-27632 and fasudil also decreased deformability, but had no effect on LPA-induced reduction of deformability. Rho inhibitor C3 had no effect on RhoA activation. Reduction in RhoA activation was induced by sub-hemolytic mechanical stress. Conclusion:Our findings may indicate that the Rho/Rho-kinase pathway could contribute to the regulation of deformability of human erythrocytes.

Özet

Amaç:Nitrik oksid, sAMP, sGMP ve protein kinazların rol oynadığı çok çeşitli hücre içi sinyal mekanizmasının etkileyebildiği eritrosit deformabilitesi mikrosirkülasyonun devamlılığında rol oynayan en önemli fizyolojik faktördür. Ancak, hücre şekil değişiklikleri ve aktin hücre iskeleti reorganizasyonu gibi hücresel olaylara aracılık eden Rho/Rho-kinaz yolağının eritrositlerdeki fonksiyonel önemi henüz tam olarak ortaya konulmamıştır. Bu yüzden, söz konusu sinyal ileti mekanizmasının çeşitli aktivatör ve inhibitörlerinin eritrosit deformabilitesi üzerine etkisini inceledik. Gereç ve Yöntemler:Eritrositlerde RhoA ve ROCK-2 proteinleri Western-Blot yöntemi ile gösterildi. Her iki Rho-kinaz inhibitörü fasudil ve y-27632'nin (10-7-10-4 M) eritrosit deformabilitesi üzerine etkisi çeşitli sıvı kayma kuvvetlerinde (0-30 Pa) bilinen bir Rho aktivatörü olan lizofosfatidik asit (LPA, 10-5- 5x10-5 M, 1-15 dakika) varlığında ve yokluğunda incelendi Bulgular: LPA inkübasyonu Rho-GTP inhibisyonu ile eşzamanlı olarak deformabiliteyi azalttı. Y-27632 ve fasudil de tek başlarına deformabiliteyi azalttı ancak LPA ile indüklenen deformabilite azalmasını etkilemedi. Rho inhibitörü C3 ekzoenzim RhoA aktivasyonunu etkilemedi. Öte yandan subhemolitik mekanik stress uygulaması RhoA aktivasyonunu azalttı. Sonuç: Sonuç olarak bulgularımız Rho/Rho-kinaz yolağının insan eritrositlerinde deformabilitenin düzenlenmesine katkı yapabileceğine işaret edebilir.

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Cite This Article

TİFTİK, R. N., BAŞKURT, O. K., KUL, S., BÜYÜKAFŞAR, K. (2014). The Functional Significance of the Rho/Rho-Kinase Pathway in Human Erythrocytes. Turkish Journal of Hematology, Cilt: 31 - Sayı: 2, 168–174. https://ajindex.com/articles/412543

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