Hookana Eeva, Junttila M Juhani, Kaikkonen Kari S, Porvari Katja, Kaija Helena, Risteli Juha, Kortelainen Marja-Leena, Huikuri Heikki V
Department of Internal Medicine, University of Oulu , Oulu , Finland.
Ann Med. 2014 Aug;46(5):318-23. doi: 10.3109/07853890.2014.898862. Epub 2014 May 9.
Idiopathic myocardial fibrosis (IMF) was observed to be the most prevalent autopsy finding in the victims of sudden cardiac death (SCD) under the age of 40 years in the FinGesture cohort. To elucidate further the mechanisms of IMF, we examined the collagen composition from the myocardial samples taken from the victims of IMF-associated SCD.
Eighteen cases with IMF as a cause of death, confirmed by autopsy, were selected for the analysis. Controls (n = 27) included were cases in whom no cardiac or non-cardiac disease could be found as a cause of unexpected death at autopsy. In addition to conventional histological examination, immunohistochemical staining of procollagens I and III (PINP and PIINP), mature collagen III (IIINTP), and the cross-linked collagen I degradation product (ICTP) were performed.
Increased accumulation of PINP was observed in the fibrotic tissue of the IMF cases in comparison with control samples. In contrast, type III collagen was not as frequently expressed in the fibrotic areas.
Myocardial accumulation of PINP in the victims of IMF-associated SCD indicates increased type I collagen synthesis. Future studies on the role of circulating type I collagen biomarkers are needed to study further the implications of the described association.
在芬兰手势队列研究中，特发性心肌纤维化（IMF）被观察到是40岁以下心脏性猝死（SCD）受害者中最常见的尸检发现。为了进一步阐明IMF的机制，我们检查了与IMF相关的SCD受害者心肌样本中的胶原蛋白组成。
选择18例经尸检确诊为IMF导致死亡的病例进行分析。对照组（n = 27）包括在尸检中未发现心脏或非心脏疾病是意外死亡原因的病例。除了常规组织学检查外，还进行了前胶原蛋白I和III（PINP和PIINP）、成熟胶原蛋白III（IIINTP）以及交联胶原蛋白I降解产物（ICTP）的免疫组织化学染色。
与对照样本相比，在IMF病例的纤维化组织中观察到PINP的积累增加。相比之下，III型胶原蛋白在纤维化区域的表达不那么频繁。
与IMF相关的SCD受害者心肌中PINP的积累表明I型胶原蛋白合成增加。需要进一步研究循环I型胶原蛋白生物标志物的作用，以进一步研究所述关联的意义。
