Accumulation of collagen in the uterus of the immature rat administered estradiol-17 beta

Strain-specific induction of endometrial periglandular fibrosis in mice exposed during adulthood to the endocrine disrupting chemical bisphenol A

The aim of this study was to compare effects of bisphenol A (BPA) on collagen accumulation in uteri of two mouse strains. Adult C57Bl/6N and CD-1 mice were exposed to dietary BPA (0.004-40mg/kg/day) or 17α-ethinyl estradiol (0.00002-0.001mg/kg/day) as effect control. An equine endometrosis-like phenotype with increased gland nesting and periglandular collagen accumulation was characteristic of unexposed C57Bl/6N, but not CD-1, endometrium. BPA non-monotonically increased gland nest density and periglandular collagen accumulation in both strains. Increased collagen I and III expression, decreased matrix metalloproteinase 2 (MMP2) and MMP14 expression, and increased immune response were associated with the endometrosis phenotype in the C57Bl/6N strain and the 30ppm BPA CD-1 group. The association between the pro-collagen shift in increased collagen expression and decreased MMP2 expression and activity implies that strain differences and BPA exposure alter regulation of endometrial remodeling and contribute to increased fibrosis, a component of several human uterine diseases.

Alteration of collagen biosynthesis and analysis of type I and type III collagens of prostate in young rats following sex hormone treatments

Two series of experiments were conducted to clarify the collagen biosynthesis and isolation of type I and type III collagens of young rats that received various sex hormone treatments. Evidence has been presented that (1) estradiol-17 beta treatment induces prostatic atrophy and suppresses the incorporation of [3H]proline into collagen in prostate; (2) administration of estradiol-17 beta increases the collagen content in the prostate; (3) localization of type I and III collagens in the interstitium of the prostate is detected by indirect immunofluorescence staining; (4) the ratio of type III collagen to type I collagen in the gland decreases following estradiol-17 beta treatment; and (5) neither treatment with testosterone nor administration of testosterone plus estradiol-17 beta in precastrated rats shows discernible effects on these valuables. These findings suggest that estradiol-17 beta increases the accumulation of collagen into the prostate with different extents of influence on the synthesis of type I and III collagens.

The effect of oestradiol-17 beta on connective tissue protein in rat prostate

The concentrations of collagen, non-collagenous protein and elastin in ventral and dorsolateral prostates in oestradiol-17 beta-treated rats were higher than in vehicle-treated rats. The in vivo incorporation rates of 3H-proline into these connective tissue proteins in ventral and dorsolateral prostates were reduced following oestradiol-17 beta-treatment. The degradation rate of 3H-proline incorporated into each connective tissue protein was lowest in oestradiol-17 beta-treated animals. These findings indicate that the accumulation of collagen, non-collagenous protein and elastin in prostates of oestradiol-17 beta-treated rats can be largely accounted for by the suppressed degradation of biosynthesis of these connective tissue proteins.

Histologic, morphometric, and immunocytochemical analysis of myometrial development in rats and mice: I. Normal development

Myometrial development from the prenatal to adult period was examined in rats and mice 1) by histologic and immunocytochemical methods with anti-actin, -vimentin, and -laminin to assess cytodifferentiation of smooth muscle and fibroblastic cells; and 2) by morphometric procedures to assess quantitatively the expression of cellular orientation in the emerging inner circular myometrial layer. Uterine mesenchymal cells initially were uniformly vimentin-positive, undifferentiated, and randomly oriented during the late fetal period. By the early neonatal period, three mesenchymal layers became recognizable histologically, the middle one of which (prospective circular myometrium) developed distinct circular orientation and differentiated into a layer composed of actin-positive smooth muscle cells. The cells of the inner mesenchymal layer initially exhibited radial orientation. By 10 days postpartum, the outer longitudinal mesenchymal layer differentiated into bundles of smooth muscle cells representing the longitudinal myometrium. The inner mesenchymal layer remained vimentin-positive and differentiated into the randomly ordered endometrial stroma. The cells of the middle and outer mesenchymal layers that were destined to form myometrium initially expressed vimentin throughout and then coexpressed vimentin and actin, but with time vimentin staining disappeared in the maturing smooth muscle cells as they expressed actin.

Histologic, morphometric, and immunocytochemical analysis of myometrial development in rats and mice: II. Effects of DES on development

The effects of diethylstilbestrol (DES) treatment on myometrial development from the prenatal to adult period were examined in rats and mice by histologic and immunocytochemical methods using anti-actin, -vimentin, and -laminin to assess cytodifferentiation of smooth muscle and fibroblastic cells, and by morphometric procedures to assess quantitatively the effect of DES on the expression of cellular orientation in the emerging inner circular myometrial layer. Neonatal rats and mice were treated with DES from day 0 (day of birth) to day 2 with dosages known to perturb myometrial development. Neonatal treatment with DES increased the degree of circular orientation within the uterine mesenchyme, an effect detectable following as little as 24 hr of DES treatment. This effect on spatial organization of the mesenchyme was followed by an increase in the thickness of the actin-positive middle layer (prospective circular myometrium) of uterine mesenchyme during days 3-15; from day 15 onward, however, the circular myometrial layer began to fragment into irregular bundles of smooth muscle, and the longitudinal myometrial layer became thinner and more irregularly organized than controls. Vimentin localization in rats treated with DES neonatally was more intense than in controls within the circularly orientated uterine mesenchyme at 5 days. By 60 days the circular and longitudinal myometrial layers of DES-treated animals showed strands and bundles of vimentin-positive cells, which were not present in controls. Both rats and mice show comparable effects of DES treatment.

Inhibition of prolyl hydroxylase activity and collagen biosynthesis by the anthraquinone glycoside, P-1894B, an inhibitor produced by Streptomyces albogriseolus

P-1894B, a potent prolyl hydroxylase inhibitor produced by Streptomyces albogriseolus subsp. No. 1894, inhibited about 50% of the activity of purified chick embryo prolyl hydroxylase at a concentration of 2.2 x 10(-6) M. The inhibition was noncompetitive with respect to (Pro-Pro-Gly)5 with a Ki of 1.8 x 10(-6)M. When excess amounts of ferrous ions or ascorbate were added to the reaction mixture, the inhibition was slightly reversed. P-1894B at a dose of 0.15 mg/kg reduced the hydroxylation of peptidyl proline and caused a significant inhibition of collagen biosynthesis in the uterus of the immature rat stimulated by the administration of estradiol-17 beta.