title: Calpain and Caspase-12 Expression in Lens Epithelial Cells of Diabetic Cataracts.
abstract: OBJECTIVE
  To compare the expression of calpain and caspase-12 in human lens epithelial cells (LECs) of cataract patients with or without diabetic retinopathy (DR).
  
  
  METHODS
  Prospective, comparative case series.
  
  
  METHODS
  Patients were divided into 4 groups: patients without diabetes mellitus (DM) (Group 1), patients with DM and without diabetic retinopathy (DR) (Group 2), diabetic patients with nonprolifeative DR (NPDR) (Group 3), and diabetic patients with proliferative DR (PDR) (Group 4). Data on DM duration and glycated hemoglobin (HbA1c) level were collected. The LECs were obtained during cataract surgery and immunohistochemical staining was performed for calpain and caspase-12. The reactivity score of each specimen was determined using confocal microscopy.
  
  
  RESULTS
  A total of 40 patients (40 eyes) were evaluated, and each group was composed of 10 patients. The expression of calpain and caspase-12 was highest in Group 4, followed by Group 3, Group 2, and Group 1 (P < .001). The expressions were significantly higher with a longer duration of DM, increased HbA1c level, or advanced DR.
  
  
  CONCLUSIONS
  Endoplasmic reticulum stress may be associated with apoptosis of LECs, resulting in cataract formation in diabetic patients.
authors.affiliation: Department of Ophthalmology and Visual Science, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Ye Jin
authors.initials: YJ
authors.lastname: Ahn
authors.affiliation: Department of Ophthalmology and Visual Science, Seoul St Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
authors.forename: Man Soo
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology & Visual Science, St Paul's Hospital, College of Medicine, The Catholic University of Korea, Seoul, South Korea. Electronic address: eyedoc@catholic.ac.kr.
authors.forename: Sung Kun
authors.initials: SK
authors.lastname: Chung
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002154:Calpain / Q000378:metabolism*; D053454:Caspase 12 / Q000378:metabolism*; D002386:Cataract / Q000378:metabolism* / Q000473:pathology; D003920:Diabetes Mellitus / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism* / Q000473:pathology; D019084:Fluorescent Antibody Technique, Indirect; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007908:Lens, Crystalline / Q000473:pathology*; D018613:Microscopy, Confocal; D008875:Middle Aged; D011446:Prospective Studies
chemical_list: D002154:Calpain; D053454:Caspase 12; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human; C506444:CASP12 protein, human; C484806:CAPN1 protein, human