TGF beta signaling reinforces pericyte properties of the non-endocrine mouse pituitary cell line TtT/GF
CELL AND TISSUE RESEARCH
Authors: Tsukada, Takehiro; Yoshida, Saishu; Kito, Keiji; Fujiwara, Ken; Yako, Hideji; Horiguchi, Kotaro; Isowa, Yukinobu; Yashiro, Takashi; Kato, Takako; Kato, Yukio
Abstract
The non-endocrine TtT/GF mouse pituitary cell line was derived from radiothyroidectomy-induced pituitary adenoma. In addition to morphological characteristics, because the cells are S100 beta-positive, they have been accepted as a model of folliculostellate cells. However, our recent microarray analysis indicated that, in contrast to folliculostellate cells, TtT/GF cells might not be terminally differentiated, as they share some properties with stem/progenitor cells, vascular endothelial cells and pericytes. The present study investigates whether transforming growth factor beta (TGF beta) can elicit further differentiation of these cells. The results showed that canonical (Tgfbr1 and Tgfbr2) and non-canonical TGF beta receptors (Tgfbr3) as well as all TGF beta ligands (Tgfb1-3) were present in TtT/GF cells, based on reverse transcription PCR. SMAD2, an intercellular signaling molecule of the TGF beta pathway, was localized in the nucleus upon TGF beta signaling. Furthermore, TGF beta induced cell colony formation, which was completely blocked by a TGF beta receptor I inhibitor (SB431542). Real-time PCR analysis indicated that TGF beta downregulated stem cell markers (Sox2 and Cd34) and upregulated pericyte markers (Nestin and Ng2). Double immunohistochemistry using mouse pituitary tissue confirmed the presence of NESTIN/NG2 double-positive cells in perivascular areas where pericytes are localized. Our results suggest that TtT/GF cells are responsive to TGF beta signaling, which is associated with cell colony formation and pericyte differentiation. As pericytes have been shown to regulate angiogenesis, tumorigenesis and stem/progenitor cells in other tissues, TtT/GF cells could be a useful model to study the role of pituitary pericytes in physiological and pathological processes.
Moderate prenatal ethanol exposure in the rat promotes kidney cell apoptosis, nephron deficits, and sex-specific kidney dysfunction in adult offspring
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
Authors: Akison, Lisa K.; Probyn, Megan E.; Gray, Stephen P.; Cullen-McEwen, Louise A.; Tep, Karrona; Steane, Sarah E.; Gobe, Glenda C.; Wlodek, Mary E.; Bertram, John F.; Moritz, Karen M.
Abstract
Alcohol during pregnancy can impair fetal development and result in offspring with neurodevelopmental deficits. Less is known about how low to moderate alcohol exposure can affect other organs, such as the kidney. Here, the effects of moderate ethanol exposure throughout pregnancy on kidney development were examined using a rat model. Rats were fed a liquid diet containing 6% ethanol (vol/vol) or control (0% ethanol) throughout pregnancy. Kidneys were collected at embryonic day (E) 20 or postnatal day (PN) 30 and total glomerular (nephron) number determined using unbiased stereology. Kidney function was examined in offspring at 8 and 19 months. At E20, fetuses exposed to ethanol had fewer nephrons with increased apoptosis. Alcohol exposure caused kidney dysregulation of pro- (Bax) and anti- (Bcl-2) apoptotic factors, and reduced expression of the cell proliferation marker, Ki67. Prenatal alcohol decreased expression of Gdnf and Tgfb1, important regulators of branching morphogenesis, in male fetuses. At PN30, kidney volume and nephron number were lower in offspring exposed to prenatal alcohol. Urine flow and osmolality were normal in offspring exposed to alcohol however sodium excretion tended to be lower in females prenatally exposed to alcohol. Findings suggest exposure to moderate levels of alcohol during pregnancy results in impaired kidney development and leads to a permanent nephron deficit. Although the impact on adult kidney function was relatively minor, these data highlight that even at moderate levels, alcohol consumption during pregnancy can have deleterious long-term outcomes and should be avoided.