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A comparison of antioxidant enzyme activities in organ-cultured rhesus monkey lenses following peroxide challenge.
Curr Eye Res. 1996 Aug; 15(8):845-51.CE

Abstract

PURPOSE

To analyze the activities of catalase, glutathione peroxidase and superoxide dismutase, three enzymes involved in the detoxification of reactive oxygen species in organ-cultured Rhesus monkey lenses.

METHODS

Lenses freshly obtained from Rhesus monkeys were incubated at 37 degrees C for 2 h and assessed for lens integrity. Lenses were then oxidatively stressed by exposure to a bolus of hydrogen peroxide. The three enzyme activities were assayed 2, 4 and 24 h after exposure to the peroxide challenge.

RESULTS

Freshly dissected lenses placed in organ culture exhibited a 20% decrease in catalase activity within 2 h. During the course of a 24 h incubation, catalase activity continued to decrease to a level 58% below that of freshly dissected monkey lenses. In contrast, the activity levels of both glutathione peroxidase and superoxide dismutase increased dramatically within the first 2 h of organ culture, with superoxide dismutase being most affected. Although glutathione peroxidase activity declined with incubation time, its level at the end of 24 h was still 36% greater than that of the fresh lenses. Superoxide dismutase activity remained elevated throughout the 24 h incubation period. The addition of a bolus of 0.25mM H2O2 to monkey lenses in culture had no effect on catalase activity. Two h after the peroxide insult, glutathione peroxidase activity decreased in comparison to control levels while the activity of superoxide dismutase increased by 43%. After 24 h, superoxide dismutase activity returned to values equivalent to the controls. In lenses challenged with 0.50mM H2O2, catalase and glutathione peroxidase activities decreased at 2 h, while superoxide dismutase activity increased 67% above control levels. At subsequent timepoints, catalase activity increased and reached control levels. In contrast, glutathione peroxidase activity continued to decrease with time eventually reaching fresh lens levels. Superoxide dismutase activity levels remained elevated and were equivalent to control values at 24 h.

CONCLUSIONS

The data indicate that placement of monkey lenses into an organ culture system represents an environmental change sufficient to cause a response in antioxidant enzyme levels. The addition of H2O2 to this environment caused only superoxide dismutase to be stimulated above control lens levels.

Authors+Show Affiliations

Laboratory of Mechanisms of Ocular Diseases, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Comparative Study
Journal Article

Language

eng

PubMed ID

8921227

Citation

Tumminia, S J., et al. "A Comparison of Antioxidant Enzyme Activities in Organ-cultured Rhesus Monkey Lenses Following Peroxide Challenge." Current Eye Research, vol. 15, no. 8, 1996, pp. 845-51.
Tumminia SJ, Chambers C, Qin C, et al. A comparison of antioxidant enzyme activities in organ-cultured rhesus monkey lenses following peroxide challenge. Curr Eye Res. 1996;15(8):845-51.
Tumminia, S. J., Chambers, C., Qin, C., Zigler, J. M., & Russell, P. (1996). A comparison of antioxidant enzyme activities in organ-cultured rhesus monkey lenses following peroxide challenge. Current Eye Research, 15(8), 845-51.
Tumminia SJ, et al. A Comparison of Antioxidant Enzyme Activities in Organ-cultured Rhesus Monkey Lenses Following Peroxide Challenge. Curr Eye Res. 1996;15(8):845-51. PubMed PMID: 8921227.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - A comparison of antioxidant enzyme activities in organ-cultured rhesus monkey lenses following peroxide challenge. AU - Tumminia,S J, AU - Chambers,C, AU - Qin,C, AU - Zigler,J M,Jr AU - Russell,P, PY - 1996/8/1/pubmed PY - 2001/3/28/medline PY - 1996/8/1/entrez SP - 845 EP - 51 JF - Current eye research JO - Curr Eye Res VL - 15 IS - 8 N2 - PURPOSE: To analyze the activities of catalase, glutathione peroxidase and superoxide dismutase, three enzymes involved in the detoxification of reactive oxygen species in organ-cultured Rhesus monkey lenses. METHODS: Lenses freshly obtained from Rhesus monkeys were incubated at 37 degrees C for 2 h and assessed for lens integrity. Lenses were then oxidatively stressed by exposure to a bolus of hydrogen peroxide. The three enzyme activities were assayed 2, 4 and 24 h after exposure to the peroxide challenge. RESULTS: Freshly dissected lenses placed in organ culture exhibited a 20% decrease in catalase activity within 2 h. During the course of a 24 h incubation, catalase activity continued to decrease to a level 58% below that of freshly dissected monkey lenses. In contrast, the activity levels of both glutathione peroxidase and superoxide dismutase increased dramatically within the first 2 h of organ culture, with superoxide dismutase being most affected. Although glutathione peroxidase activity declined with incubation time, its level at the end of 24 h was still 36% greater than that of the fresh lenses. Superoxide dismutase activity remained elevated throughout the 24 h incubation period. The addition of a bolus of 0.25mM H2O2 to monkey lenses in culture had no effect on catalase activity. Two h after the peroxide insult, glutathione peroxidase activity decreased in comparison to control levels while the activity of superoxide dismutase increased by 43%. After 24 h, superoxide dismutase activity returned to values equivalent to the controls. In lenses challenged with 0.50mM H2O2, catalase and glutathione peroxidase activities decreased at 2 h, while superoxide dismutase activity increased 67% above control levels. At subsequent timepoints, catalase activity increased and reached control levels. In contrast, glutathione peroxidase activity continued to decrease with time eventually reaching fresh lens levels. Superoxide dismutase activity levels remained elevated and were equivalent to control values at 24 h. CONCLUSIONS: The data indicate that placement of monkey lenses into an organ culture system represents an environmental change sufficient to cause a response in antioxidant enzyme levels. The addition of H2O2 to this environment caused only superoxide dismutase to be stimulated above control lens levels. SN - 0271-3683 UR - https://www.unboundmedicine.com/medline/citation/8921227/A_comparison_of_antioxidant_enzyme_activities_in_organ_cultured_rhesus_monkey_lenses_following_peroxide_challenge_ L2 - https://www.tandfonline.com/doi/full/10.3109/02713689609017625 DB - PRIME DP - Unbound Medicine ER -