Unfolded protein response activation in cataracts.

PURPOSE: To analyze the expression of 78 kDa glucose-regulated protein (GRP78) and activating transcription factor 6 (ATF6), 2 factors in the unfolded protein response (UPR), in age-related and diabetes-associated cataract. SETTING: Universidad Autónoma de Aguascalientes, Aguascalientes, México. DESIGN: Experimental study. METHODS: The qualitative and quantitative expression of GRP78 and ATF6 were measured in surgical samples from 11 senile cataracts, 9 diabetic-associated cataracts, and 3 normal lenses. Both proteins were detected by immunofluorescence and immunogold-conjugated antibodies. Quantitative morphometry was used to analyze the differences in GRP78 and ATF6 between samples. The Mann-Whitney test was used for statistical analysis. RESULTS: Scanning electron microscopy showed the characteristic organization of fibers in normal lenses with regular alignment and interdigitation between them. On the other hand, lenses from eyes with senile or diabetic cataract showed the same pattern of misalignment and disorganization of the fibers. Both proteins were detected through immunofluorescence in senile and diabetic cataracts, but not in normal lenses. Immunogold-conjugated antibodies and transmission electron microscopy showed that GRP78 and ATF6 grains were 30% higher and 35% higher, respectively, in diabetic cataracts than in senile cataracts (P<.05). CONCLUSIONS: These data show for the first time in humans that GRP78 and ATF6 are present in lens fibers of senile cataracts and diabetic cataracts, establishing that the UPR may be important in the process of cataractogenesis. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Differential aromatase (CYP19) expression in human arteries from normal and neoplasic uterus: an immunohistochemical and in situ hybridization study.

Aromatase CYP19 catalyzes the synthesis of estrogen from androgens in a tissue-specific manner. This enzyme is present in several tissues, including gonads, brain and fatty tissue. More recently, its presence has been described in vessels. Here, we describe the expression of aromatase in human uterine artery and compare its expression with that found in arteries of estrogen-dependent uterine leiomyomata from women. To do this, we employed immunohystochemical and in situ hybridization techniques. We used, a polyclonal antibody raised against the carboxyl terminus of aromatase (ARO) and RNAm probes, of the exon 1 of ARO. We found an increased immunoreactivity of ARO in uterine arteries of patients with leiomyoma as compared with control group. Probe showing positive signal in skin fibroblasts (1b), showed positive hybridization signal in normal artery, while probes with positive signal in placenta (1a), ovary (1c) and testis (1d) were over-expressed in arteries of leiomyomas.