Genistein and genistein-containing dietary supplements accelerate the early stages of cataractogenesis in the male ICR/f rat

Abstract

Cataract-related loss of vision affects large numbers of people in today’s aging populations and presents a healthcare burden to many nations. The role of dietary supplements within the lens is largely unknown, although benefits from dietary antioxidants are expected. In this study, the effects of genistein as its aglycone, a genistein-containing dietary supplement (Novasoy®200), and a genistein-containing food (soy protein isolate, PRO-FAM 932) on the development of lens opacity were examined in the hereditary cataractous ICR/f rat. These studies were carried out in a background diet of semi-purified, isoflavone-free AIN-76A with casein as its protein source. The amount of genistein for the experimental diets was standardized to its concentration (as genistein aglycone as well as simple and complex β-glucoside conjugates) in the soy protein isolate supplement. Also tested was a high-dose genistein diet containing an 11-fold higher amount of genistein aglycone. The composition of each diet was verified by reverse-phase HPLC and blood plasma isoflavone concentrations were determined by LC-tandem mass spectrometry. The development of opacity in each lens was monitored and digitally recorded using slit-lamp examination over the course of the study. Each of the genistein-containing diets caused a significantly more rapid development of fibrous opacification in the anterior cortical region and development of apparent water clefts or vacuoles in the posterior subcapsular region than the AIN-76A control diet; however, the establishment of dense lens opacification was not significantly different between each of the diets. There was also no significant difference observed between the low-dose and high-dose genistein aglycone groups. These data suggest that genistein-containing dietary supplements accelerate the early stages of cataractogenesis in the male ICR/f rat, with no dose-dependent effects.

Genistein—Opportunities Related to an Interesting Molecule of Natural Origin

“…A result inconsistent with other studies was reported by Floyd et al [ 80 ]. In this study, rats were fed ad libitum different diets containing genistein at a concentration of 0.018% in different forms: as an aglycone or β-glucoside (derived from Novasoy ® 200 and PRO-FAM 932 Soy Protein Isolate (SPI)), and also at a concentration of 0.2% as an aglycon.…”

Regulation of Multidrug Resistance Proteins by Genistein in a Hepatocarcinoma Cell Line: Impact on Sorafenib Cytotoxicity

“…Genistein (GNT), a phytoestrogen that belongs to the family of isoflavones, is ingested as a component of vegetables (e.g. soy beans, fava beans, lupins) or as a dietary supplement [ 27 , 28 ]. GNT is considered to exert antioxidant and anticarcinogenic effects [ 29 , 30 ].…”

Isoflavone Genistein Induces Fluid Secretion and Morphological Changes in the Uteri of Post-Pubertal Rats

“…Nowadays, genistein can be found as a dietary supplement consumed by women mainly in the developed world. Soy-derived isoflavone supplements which contain high amount of genistein include a concentrated extract of soy isoflavones (Novasoy ® 200) 3 and a low fat protein product such as PRO-FAM 932 soy protein isolate (SPI) 4. High genistein consumption has been proposed to adversely affect the reproductive functions in female based on the reported high incidence of infertility in sheeps fed with a specific species of clover, ' Trifolium subterraneum', known to contain high amount of isoflavone content 5.…”