Transforming growth factor-beta1 modulates angiotensin II-induced calcium release in vascular smooth muscle cells from spontaneously hypertensive rats

Transforming Growth Factor Beta 1 Serum Levels in Patients with Preinvasive and Invasive Lesions of the Breast

Transforming growth factor beta (TGF-β)1 is thought to be involved in breast carcinogenesis. TGF-β1 acts in an antiproliferative manner in the early stages of breast carcinogenesis, but promotes tumor progression and metastases in the advanced stages of the disease. No data have been published on serum TGF-β1 in breast cancer. We investigated TGF-β1 serum levels in patients with breast cancer (n=135), ductal carcinoma in situ (DCIS) I to III (n=67) or fibroadenoma (n=35), and in healthy women (n=40) to determine its value as a differentiation marker between malignant, pre-invasive and benign diseases and as a predictive marker for metastatic spread. Median (range) TGF-β1 serum levels in patients with breast cancer, DCIS I-III or benign breast lesions and in healthy women were 48.8 (18–82.4) pg/mL, 45.3 (26.9–58.3) pg/mL, 47.2 (17.2–80.5) pg/mL and 51.6 (30.9–65.1) pg/mL, respectively (p=0.2). In breast cancer patients TGF-β1 serum levels showed no statistically significant correlation with tumor stage, lymph node involvement, histological grade, estrogen receptor status and progesterone receptor status. Our data fail to indicate any correlation between serum TGF-β1 levels and clinicopathological parameters of breast diseases. Serum TGF-β1 levels do not provide clinical information in addition to established tumor markers.

Age-dependent regulation of vasopressin V1areceptors in preglomerular vessels from the spontaneously hypertensive rat

Experiments were performed to get insight into the role of AVP receptor V1aregulation with age, i.e., during development and maintenance of high blood pressure. Previous studies showed an increased gene expression and renal vascular response to AVP in young spontaneously hypertensive rats (SHR). The age regulation of the V1areceptor was examined in preglomerular vessels from 5-, 10-, 20-, and 70-wk-old SHR using normotensive Wistar-Kyoto rats (WKY) as controls. Real-time PCR and ligand binding were used for analysis of receptor expression, and the change in cytosolic calcium concentration during stimulation of isolated preglomerular vessels with AVP was studied. Studies showed an increase of the V1areceptor protein and mRNA from 5-and 10-wk-old SHR compared with vessels from 20- and 70-wk-old SHR. In 5-wk-old SHR receptor density was 84 ± 13 fmol/mg protein, and 38 ± 11 fmol/mg protein in 70-wk-old SHR ( P < 0.05). mRNA in the 5- and 70-wk-old SHR was 15,854 ± 629 and 3,181 ± 224 V1amRNA/108 18S ribosomal RNA, respectively ( P < 0.001). Values from WKY at all ages were similar to 20- and 70-wk-old SHR. During stimulation with AVP, the change in cytosolic calcium in vessels from 5-wk-old SHR increased 234 ± 59 nM, whereas the increase was 89 ± 9 nM in 70-wk-old SHR ( P = 0.03). These results indicate that the V1areceptor is increased at protein and mRNA level during development of hypertension in SHR but is normalized when hypertension is established.

Transforming growth factor beta in cardiovascular development and function

Transforming growth factor betas (TGFbetas) are pleiotropic cytokines involved in many biological processes. Genetic engineering and tissue explanation studies have revealed specific non-overlapping roles for TGFbeta ligands and their signaling molecules in development and in normal function of the cardiovascular system in the adult. In the embryo, TGFbetas appear to be involved in epithelial-mesenchymal transformations (EMT) during endocardial cushion formation, and in epicardial epithelial-mesenchymal transformations essential for coronary vasculature, ventricular myocardial development and compaction. In the adult, TGFbetas are involved in cardiac hypertrophy, vascular remodeling and regulation of the renal renin-angiotensin system. The evidence for TGFbeta activities during cardiovascular development and physiologic function will be given and areas which need further investigation will be discussed.

Expression of matrix metalloproteinases in cyclosporin-treated gingival fibroblasts is regulated by transforming growth factor (TGF)-beta1 autocrine stimulation

BACKGROUND

Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA). The pathogenesis of this condition is not fully understood; however, recent studies show that CsA regulates the transcription of several cytokines including transforming growth factor-beta1 (TGF-beta1). The aim of this study was to investigate the potential role of TGF-beta1 in the pathogenesis of CsA-induced gingival overgrowth, exploring a possible autocrine stimulation of TGF-beta1 as a cellular regulator of synthesis of matrix metalloproteinases (MMPs) and its tissue inhibitors (TIMPs).

METHODS

Gingival fibroblasts from human normal gingiva were incubated with increasing concentrations of CsA, cultured for 24 hours, and the expression and production of TGF-beta1 determined by semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. MMP and TIMP mRNA expression levels were also analyzed by RT-PCR. To determine the effect of TGF-beta1 on the expression of MMP and TIMP by human gingival fibroblasts under CsA treatment, human gingival fibroblast cultures were treated with sense oligonucleotides (SON) or antisense oligonucleotides (AON).

RESULTS

CsA simultaneously stimulated TGF-beta1 expression and production and inhibited expression of MMP-1 and MMP-2 by human gingival fibroblasts, whereas CsA has a slight effect on TIMP-1 and TIMP-2 expression. AON reduced TGF-beta1 production as demonstrated by ELISA, whereas TGF-beta1 mRNA expression levels were not significantly modified. The inhibition of TGF-beta1 production by AON modulated MMP expression, demonstrating the autocrine inhibitory effect of TGF-beta1 in CsA-treated human gingival fibroblasts.

CONCLUSIONS

The data presented here suggest that TGF-beta1 in an autocrine fashion may contribute to a reduction of proteolytic activity of human gingival fibroblasts in CsA-induced gingival overgrowth, which favors the accumulation of extracellular matrix.

Transforming growth factor-beta 1 serum levels in pregnancy and pre-eclampsia

BACKGROUND

Isoforms of transforming growth factor-beta (TGF-beta1) are thought to be involved in the pathogenesis of pre-eclampsia. Data with respect to TGF-beta1 are controversial. We examined the correlation between TGF-beta1 serum levels and the occurrence and severity of pre-eclampsia.

METHODS

Transforming growth factor-beta 1 serum levels were measured using a commercially available enzyme-linked immunosorbent assay in 44 women with pre-eclampsia and 44 healthy pregnant women. Results were correlated with clinical data.

RESULTS

No difference in TGF-beta1 serum levels was assessed between women with pre-eclampsia and healthy pregnant women. Transforming growth factor-beta 1 serum levels were not associated with the severity of the disease and were not correlated with clinical maternal (blood pressure, proteinuria) and fetal (5-min APGAR score, umbilical cord pH values, birth weight) parameters.

CONCLUSIONS

Our data support the assumption that in contrast to other isoforms, TGF-beta1, as evidenced by serum TGF-beta1 levels, does not seem to be involved in the pathogenesis of pre-eclampsia.

Pulse pressure, endothelium function, and arterial stiffness in spontaneously hypertensive rats

In rats, removal of the carotid arterial or abdominal aortic endothelium results in an acute increase of diameter and compliance. In humans, acute local administration of a specific NO synthase inhibitor increases radial artery compliance but not the diameter. The purpose of this review is to determine whether in spontaneously hypertensive rats (SHR), a cause-and-effect relationship may be observed between endothelial function and arterial stiffness with possible consequences on pulse pressure (PP) control. The study is based on a comparative time-dependent analysis of the following in young and old SHR: aortic blood pressure measurements and reactivity, ultrasonographic arterial stiffness assessment, aortic histomorphometry and staining, and molecular biology with evaluation of endothelium function. In young SHR, aortic mean blood pressure and PP increase proportionally, whereas isobaric arterial stiffness is unchanged or poorly modified. The endothelial NO response to norepinephrine is normal or upregulated as a response to predominant vasoconstrictive influences. In contrast, in old SHR, PP and mean blood pressure change disproportionately with age, together with an enhanced isobaric arterial stiffness. The endothelial NO response to norepinephrine is abolished, in association with endothelium-dependent heightened norepinephrine reactivity and enhanced accumulation of vessel extracellular matrix. In this latter case, exogenous NO acutely and selectively lowers the increased PP. Thus, during SHR aging, a negative feedback may be observed between NO bioactivity and PP through changes in arterial structure and function. Whether this alteration contributes to the development of systolic hypertension in old populations remains to be determined.