Min Wei1, Kui-Yi Xing2, Yin-Chuan Fan3, Teodosio Libondi4, Marjorie F Lou5. 1. Department of Ophthalmology, Sichuan Provincial People's Hospital, Chengdu, China School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Nebraska, United States. 2. School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Nebraska, United States Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska, United States. 3. Department of Ophthalmology, Sichuan Provincial People's Hospital, Chengdu, China. 4. Second University Eye Department, the Second University, Naples, Italy. 5. School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Nebraska, United States Redox Biology Center, University of Nebraska-Lincoln, Lincoln, Nebraska, United States Department of Ophthalmology, University of Nebraska Medical Center, Omaha, Nebraska, United States.
Abstract
PURPOSE: The purpose of this study was to investigate the thiol repair systems of thioltransferase (TTase) and thioredoxin (Trx) and oxidation-damaged proteins in human cataractous lenses. METHODS: Cataractous lenses in humans (57-85 years of age) were classified into cortical, nuclear, mixed, mature, and hypermature cataract types by using a lens opacity classification system, and were obtained by extracapsular cataract extraction (ECCE) procedure. Cortical and nuclear cataracts were grouped by decreasing order of visual acuity into optical chart reading (R), counting fingers (CF), hand motion (HM), and light perception (LP). ECCE lens homogenate was analyzed for glutathione (GSH) level and enzyme activities of TTase, glutathione reductase (GR), Trx, and thioredoxin reductase (TR). Cortical and nuclear cataractous lenses (8 of each) with visual acuity better than HM were each dissected into cortical and nuclear portions for measurement of glyceraldehyde 3-phosphate dehydrogenase (G3PD) activity. Clear lenses (in humans 49-71 years of age) were used as control. RESULTS: Compared with control, all cataractous lenses lost more than 80% GSH and 70% GR; TR and Trx activity; and 40% to 70% TTase activity, corroborated with the loss in visual acuity. Among cataracts with R and CF visual acuity, cortical cataract lost more cortical G3PD activity (18% of control) than that of nuclear cataract (50% of control), whereas GSH depletion and TTase inactivation were similar in both cataracts. CONCLUSIONS: Thiol repair systems were damaged in all types of cataracts. Cortical and nuclear cataracts showed differential G3PD inactivation in the cortex, implying those 2 type of cataracts might be formed through different mechanisms. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.
PURPOSE: The purpose of this study was to investigate the thiol repair systems of thioltransferase (TTase) and thioredoxin (Trx) and oxidation-damaged proteins in humancataractous lenses. METHODS:Cataractous lenses in humans (57-85 years of age) were classified into cortical, nuclear, mixed, mature, and hypermature cataract types by using a lens opacity classification system, and were obtained by extracapsular cataract extraction (ECCE) procedure. Cortical and nuclear cataracts were grouped by decreasing order of visual acuity into optical chart reading (R), counting fingers (CF), hand motion (HM), and light perception (LP). ECCE lens homogenate was analyzed for glutathione (GSH) level and enzyme activities of TTase, glutathione reductase (GR), Trx, and thioredoxin reductase (TR). Cortical and nuclear cataractous lenses (8 of each) with visual acuity better than HM were each dissected into cortical and nuclear portions for measurement of glyceraldehyde 3-phosphate dehydrogenase (G3PD) activity. Clear lenses (in humans 49-71 years of age) were used as control. RESULTS: Compared with control, all cataractous lenses lost more than 80% GSH and 70% GR; TR and Trx activity; and 40% to 70% TTase activity, corroborated with the loss in visual acuity. Among cataracts with R and CF visual acuity, cortical cataract lost more cortical G3PD activity (18% of control) than that of nuclear cataract (50% of control), whereas GSH depletion and TTase inactivation were similar in both cataracts. CONCLUSIONS:Thiol repair systems were damaged in all types of cataracts. Cortical and nuclear cataracts showed differential G3PD inactivation in the cortex, implying those 2 type of cataracts might be formed through different mechanisms. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.
Entities:
Keywords:
PSSG; PSSP; glyceraldehyde 3-phosphodehydrogenase; human cataract; oxidative stress; redox regulation; thiol oxidation damage repair; thioltransferase system; thioredoxin system
Authors: Megan A Rocha; Marc A Sprague-Piercy; Ashley O Kwok; Kyle W Roskamp; Rachel W Martin Journal: Chembiochem Date: 2021-02-10 Impact factor: 3.164