Heat in Workplaces Such as a Neighborhood Bakery or a Glass Factory Can Promote Aging of the Eye Lens

ABSTRACT

Aging can be described as accumulation of damage with time. The eye lens is a good model for study the aging process because of limited repair mechanisms. The function of the eye lens is to help the cornea focus light on the retina and consequently the lens must remain transparent throughout life. Cataracts (loss of lens transparency) are a major cause of blindness in the aging population. Despite the amount of research done, the mechanisms of cataract formation are not completely understood. One of the major insults that can promote cataract is exposure to heat. Many workers are exposed to high temperatures in bakeries and glass factories. We investigated the mechanisms involved in heat damage in such work-places on the eye lens using a unique lens organ culture system. Bovine lenses were placed in specially designed culture containers for incubation of 11 to 15 days. Lenses were exposed to 39.5°C or 37.8°C by simulating the heat reaching the eye lens in a neighborhood bakery (39.5°C) and a glass factory (37.8°C). Lens optical quality was followed and lens epithelial samples were analyzed for ATPase activities. Lenses exposed to both temperatures show changes in lens optical quality and damage to lens epithelial cells. Lenses exposed to 37.8°C show an increase in lens epithelial ATPase activities. Lenses exposed to 39.5°C show a reduction in ATPase activities.