Nanosized TiO2-Induced Reproductive System Dysfunction and Its Mechanism in Female Mice

Abstract

Recent studies have demonstrated nanosized titanium dioxide (nano-TiO2)-induced fertility reduction and ovary injury in animals. To better understand how nano-TiO2 act in mice, female mice were exposed to 2.5, 5, and 10 mg/kg nano-TiO2 by intragastric administration for 90 consecutive days; the ovary injuries, fertility, hormone levels, and inflammation-related or follicular atresia-related cytokine expression were investigated. The results showed that nano-TiO2 was deposited in the ovary, resulting in significant reduction of body weight, relative weight of ovary and fertility, alterations of hematological and serum parameters and sex hormone levels, atretic follicle increases, inflammation, and necrosis. Furthermore, nano-TiO2 exposure resulted in marked increases of insulin-like growth factor-binding protein 2, epidermal growth factor, tumor necrosis factor-α, tissue plasminogen activator, interleukin-1β, interleukin -6, Fas, and FasL expression, and significant decreases of insulin-like growth factor-1, luteinizing hormone receptor, inhibin α, and growth differentiation factor 9 expression in mouse ovary. These findings implied that fertility reduction and ovary injury of mice following exposure to nano-TiO2 may be associated with alteration of inflammation-related or follicular atresia-related cytokine expressions, and humans should take great caution when handling nano-TiO2.

Effects of resveratrol on ovarian response to controlled ovarian hyperstimulation in ob/ob mice

“…An interesting finding of the present study was that resveratrol treatment in ob/ob mice resulted in a decrease of the number of atretic follicles. Because high TNF-a, IL-6, and androgen levels may promote follicular atresia (13,24,66), resveratrol could ameliorate this predominant ovarian event through the decrease of T and these proinflammatory cytokines. Likewise, it has been reported that resveratrol may inhibit apoptosis of oocytes (32), thus follicles may be rescued from undergoing atresia.…”

Copper nanoparticle-induced ovarian injury, follicular atresia, apoptosis, and gene expression alterations in female rats

“…24 The ovarian injury may be associated with alteration of inflammation-related or follicular-atresia-related cytokine expression. 25 In addition, gold NPs can enter Chinese hamster ovary cells through the endocytic pathway, 26 infiltrate rat ovarian granulosa cells and subcellular organelles, and alter in vitro estrogen accumulation. 27 Moreover, mitogen-activated protein kinase cellular signal transduction pathways in mammalian cells can be activated by silicon carbide nanowires.…”

Effect of titanium dioxide nanoparticles on male and female reproductive systems

“…Additionally, serum parameters, sex hormone levels and atretic follicle count increased, and inflammation and necrosis were observed. In addition, inflammation-related or follicular atresia-related cytokine expressions were altered, which shows that fertility reduction and ovary injury of mice is associated with inflammatory factors [36].…”