Jill G. Kerl

Neutralization of vascular endothelial growth factor antiangiogenic isoforms or administration of proangiogenic isoforms stimulates vascular development in the rat testis

Vascular endothelial growth factor A (VEGFA) plays a role in both angiogenesis and seminiferous cord formation, and alternative splicing of the Vegfa gene produces both proangiogenic isoforms and antiangiogenic isoforms (B-isoforms). The objectives of this study were to evaluate the expression of pro- and antiangiogenic isoforms during testis development and to determine the role of VEGFA isoforms in testis morphogenesis. Quantitative RT-PCR determined that Vegfa_165b mRNA was most abundant between embryonic days 13.5 and 16 (E13.5 and 16; P<0.05). Compared with ovarian mRNA levels, Vegfa_120 was more abundant at E13-14 (P<0.05), Vegfa_164 was less abundant at E13 (P<0.05), and Vegfa_165b tended to be less abundant at E13 (P<0.09) in testes. Immunohistochemical staining localized antiangiogenic isoforms to subsets of germ cells at E14-16, and western blot analysis revealed similar protein levels for VEGFA_165B, VEGFA_189B, and VEGFA_206B at this time point. Treatment of E13 organ culture testes with VEGFA_120, VEGFA_164, and an antibody to antiangiogenic isoforms (anti-VEGFAxxxB) resulted in less organized and defined seminiferous cords compared with paired controls. In addition, 50 ng/ml VEGFA_120 and VEGFA_164 treatments increased vascular density in cultured testes by 60 and 48% respectively, and treatment with VEGFAxxxB antibody increased vascular density by 76% in testes (0.5 ng/ml) and 81% in ovaries (5 ng/ml) compared with controls (P<0.05). In conclusion, both pro- and antiangiogenic VEGFA isoforms are involved in the development of vasculature and seminiferous cords in rat testes, and differential expression of these isoforms may be important for normal gonadal development.

Genes involved in the immediate early response and epithelial–mesenchymal transition are regulated by adipocytokines in the female reproductive tract

Obesity increases the risk of female reproductive tract cancers, but the underlying mechanistic link between the two is ill‐defined. Thus, the objective of the current study was to identify obesity‐dependent changes in the expression of immediate early (IE) genes that contribute to cell proliferation and differentiation, and epithelial–mesenchymal transition (EMT) genes that promote cell migration. When HeLa cells were treated for 0–48 hr with IGF‐1, leptin, TNFα, or IL‐6, each individual adipocytokine altered the abundance of IE (cJUN, cFOS, and cMYC) and EMT (SNAI1, SNAI2, and TWIST1) mRNA abundance. For example, IGF‐1 increased cJUN and cFOS and decreased cMYC; leptin increased cFOS; IL‐6 increased cFOS and cMYC; and TNFα increased cJUN and cFOS mRNA abundance. Likewise, EMT gene expression was altered by IGF‐1, TNFα, and IL‐6. SNAI1 was increased by IGF‐1 and IL‐6; SNAI2 was increased by IGF‐1 and TNFα; and TWIST1 was increased by TNFα and IL‐6. Chronic exposure to adipocytokines also altered EMT gene expression in the whole uterus of obese compared to normal‐weight mice. Specifically, there was no difference in cJun, cFos, or cMyc mRNA abundance between normal‐weight and obese animals. Snai1, Snai2, and Twist1 mRNA abundance, however, was increased in the uterus of obese females and correlated with increased circulating IGF‐1 levels. These data indicate that obesity‐dependent alterations in adipocytokine levels regulate the expression of genes associated with cell proliferation and migration, and therefore may provide a plausible mechanism for obesity‐dependent increases in cancers of the female reproductive tract. Mol. Reprod. Dev. 79:128–137, 2012.