title: Can apical periodontitis affect serum levels of CRP, IL-2, and IL-6 as well as induce pathological changes in remote organs?
abstract: OBJECTIVE
  The aim of this study was to investigate whether apical periodontitis (AP) could cause systemic cytokine elevation and pathological changes in remote organs in an experimental animal model.
  
  
  METHODS
  AP was induced in 36 Sprague Dawley (SD) rats. Serum levels of C-reactive protein (CRP), interleukin 2 (IL-2), and interleukin 6 (IL-6) were measured by enzyme-linked immunosorbent assays at different time intervals (0, 6, 12, 24, 48, and 96 h and 1, 2, 3, 4, 5, and 6 weeks) after pulp exposure. Multiple organs (the aortic arch, myocardium, liver, and spleen) were collected for histological observation. The results were analyzed by one-way analysis of variance (ANOVA).
  
  
  RESULTS
  Serum levels of CRP, IL-2, and IL-6 were significantly elevated at all time points assessed after 6, 24, and 96 h, respectively. The peak values of serum cytokines (CRP 6.363 ± 0.05 ng/ml, IL-2 21.997 ± 0.15 ng/L, and IL-6 2.406 ± 0.02 ng/L) were reached at 1, 4, and 2 weeks, respectively, followed by a decline. Time-dependent reversible histopathological changes were detected in the aortic arch, myocardium, and spleen, whereas irreversible changes were found in the liver.
  
  
  CONCLUSIONS
  AP elevated the levels of CRP, IL-2, and IL-6 in rat blood serum, causing reversible changes in the aortic arch, myocardium, and spleen as well as irreversible changes in the liver.
  
  
  CONCLUSIONS
  AP may trigger a systemic immune response, impair remote organs, and affect the general health of patients.
authors.affiliation: Department of Endodontics and Operative Dentistry, School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, China.
authors.forename: Jinxiu
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Endodontics and Operative Dentistry, School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, China. hxiaoj@163.com.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Endodontics and Operative Dentistry, School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, China.
authors.forename: Bingling
authors.initials: B
authors.lastname: Lu
authors.affiliation: Comprehensive Dental Care, Endodontics, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong, SAR, China.
authors.forename: Chengfei
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, Fujian, 350002, China.|School and Hospital of Stomatology, Fujian Medical University, 246 Yangqiao Zhong Road, Fuzhou, Fujian, 350002, China.
authors.forename: Zhiyu
authors.initials: Z
authors.lastname: Cai
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000473:pathology; D002097:C-Reactive Protein / Q000378:metabolism*; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay; D007376:Interleukin-2 / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood*; D008099:Liver / Q000473:pathology; D008297:Male; D009206:Myocardium / Q000473:pathology; D010485:Periapical Periodontitis / Q000097:blood* / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000473:pathology
chemical_list: D007376:Interleukin-2; D015850:Interleukin-6; D002097:C-Reactive Protein
keywords: Aortic arch; Apical periodontitis; Cytokines; Liver