Dietary glycine does not affect physiological angiogenesis and reproductive function, but inhibits apoptosis in endometrial and ovarian tissue by down-regulation of nuclear factor-κB

ObjectiveTo study the effect of dietary glycine on female reproductive organs.DesignIntravital microscopic, histologic, and biomolecular study.SettingInstitute for Clinical & Experimental Surgery, University of Saarland.Animal(s)Syrian golden hamsters.Intervention(s)Endometrial fragments and ovarian follicles were transplanted into dorsal skinfold chambers of Syrian golden hamsters, which received glycine diet or standard pellet food (control).Main Outcome Measure(s)Angiogenesis of the grafts was analyzed during 14 days using intravital fluorescence microscopy. Protein expression of proliferating cell nuclear antigen, cleaved caspase-3, p53, and nuclear factor-kappa B (NF-κB) in the eutopic endometrium and ovary was measured by Western blot analysis. Fertility and reproductive function of mating hamsters was assessed.Result(s)Dietary glycine did not affect angiogenesis of endometrial and ovarian grafts, as indicated by a vascularized area, microvessel density, and blood perfusion compared with that of grafts in control animals. In addition, glycine-treated hamsters presented with normal reproductive function. Interestingly, glycine inhibited apoptosis in endometrial and ovarian tissue by down-regulation of NF-κB expression.Conclusion(s)Our novel data indicate that glycine can be used as a therapeutic agent for inflammatory or angiogenic disorders without inducing serious side effects in the female reproductive tract.