Human placental lactogen directly inhibits rat cartilage growth processes in vivo and in vitro

1993 ◽  
Vol 128 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Mimi H Chiang ◽  
Kevin M Kelley ◽  
Charles S Nicoll

We have recently reported that human placental lactogen inhibits the growth of young female rats without changing the serum levels of insulin like growth factor-I. Accordingly, experiments were conducted to determine whether human placental lactogen could directly inhibit cartilage growth processes in vivo and in vitro. Osmotic minipumps with attached polyethylene catheters were used to infuse the hormone for seven days into the left hindlimb of three-month-old female rats via the common iliac artery. The right hindlimb of each animal served as an internal control. Infusion of the placental lactogen at 10 μg/rat/day caused a slight (10%) but significant decrease in the width of the tibial epiphysial cartilage plate and a higher dose (100 μg/rat/day) caused a greater degree of inhibition (25%). However, the higher dose also inhibited the tibial cartilage plate of the contralateral (non-infused) limb. The possibility that human placental lactogen could directly inhibit cartilage anabolic activity in vitro was evaluated by measuring the incorporation of 35SO4 into costal cartilage explants from three to four-month-old female rats. The placental hormone inhibited the incorporation of 35SO4 in a dose-related manner at concentrations ranging from 1.0 to 100 μg/l. As a test of the specificity of this inhibition the effect of the hormone on the incorporation of 35SO4 into cartilage explants from Coho salmon was determined. The placental lactogen did not affect incorporation of the sulfate into the fish cartilage over a range of doses from 1.0 to 1000 μg/l. These results indicate that at least some of the inhibitory effects of human placental lactogen on the growth of rats is direct on peripheral tissues, such as cartilage. This effect may be mediated by the well-established anti-insulin action of the placental hormone.

1985 ◽  
Vol 249 (1) ◽  
pp. E77-E88 ◽  
Author(s):  
K. C. Weiss ◽  
M. C. Linder

The time course of distribution of high-specific activity 67CuCl2 to tissues and plasma components was followed in adult, female rats. Immediately after intubation or injection, tracer 67Cu associated with two components of the blood plasma separable on columns of Sephadex G-150: albumin and another (larger) component, which was not ceruloplasmin. The latter, tentatively named transcuprein, had an apparent molecular weight of 270,000 and a high affinity for Cu2+, as judged by processing through Chelex-100, dilution, and exchange with albumin copper, in vitro and in vivo. It was capable of donating copper to tumor cells in serum-free medium. Analysis of "cold" plasma by furnace atomic absorption confirmed the presence of 10-15% of plasma copper in this peak. Plots of percent dose and 67Cu specific activity against time showed that copper followed a very specific pathway after binding to albumin and transcuprein, entering mainly the liver, then reappearing in the plasma on ceruloplasmin, and then achieving peak distribution in peripheral tissues (muscles, brain, etc.). 67Cu disappeared from liver and kidney with an apparent half-life of 4.5 days, the same exponential rate found for whole body turnover. Apparent turnover of ceruloplasmin copper was more rapid. Even after 7-12 days, tracer copper in plasma was still found exclusively with ceruloplasmin. The results indicate that copper follows a carefully prescribed path, on entering the blood and binding to a new transport protein.


1976 ◽  
Vol 71 (1) ◽  
pp. 115-120 ◽  
Author(s):  
HIROSHI NAGASAWA ◽  
REIKO YANAI ◽  
KOREHITO YAMANOUCHI

SUMMARY Intact female rats given twice daily injections of 1 mg human placental lactogen (HPL) showed continued dioestrous vaginal smears and their ovarian corpora lutea were found to be hypertrophied and functional. The serum prolactin level was significantly lower in these rats than in the controls at dioestrus as well as at pro-oestrus. Twice-daily injections of 0·5 or 2 mg HPL to ovariectomized rats decreased serum and pituitary levels of prolactin and increased hypothalamic activity of prolactin inhibiting hormone, although the effect was less at the lower dose. Human placental lactogen had no direct effect on pituitary prolactin secretion in vitro. These findings have demonstrated that HPL, like prolactin itself, inhibits prolactin secretion by acting indirectly on the pituitary through the hypothalamus.


Cartilage ◽  
2020 ◽  
pp. 194760352098015
Author(s):  
Mara H. O’Brien ◽  
Eliane H. Dutra ◽  
Shivam Mehta ◽  
Po-Jung Chen ◽  
Sumit Yadav

Objective Bone morphogenetic protein 2 (BMP2) plays important roles in cartilage growth and development. Paradoxically, elevated levels of BMP2 leads to hypertrophic differentiation and osteoarthritis of cartilage. We examined the in vivo loss of BMP2 in cells expressing aggrecan of the mandibular condyle and knee. Design Three-week-old BMP2 flox/flox- CreER-positive mice and their Cre-negative littermates were treated with tamoxifen and raised until 3 or 6 months. We also investigated the direct effects of BMP2 on chondrocytes in vitro. Cells from the mandibular condyle of mice were treated with recombinant human BMP2 (rhBMP2) or rhNoggin (inhibitor of BMP2 signaling). Results Conditional deletion of BMP2 caused breakage of the cartilage integrity in the mandibular condyle of mice from both age groups, accompanied by a decrease in cartilage thickness, matrix synthesis, mineralization, chondrocyte proliferation, and increased expression of degeneration markers, while the effects at articular cartilage were not significant. In vitro results revealed that rhBMP2 increased chondrocyte proliferation, mineralization, and differentiation, while noggin induced opposite effects. Conclusions In conclusion, BMP2 is essential for postnatal maintenance of the osteochondral tissues of the mandibular condyle.


1985 ◽  
Vol 249 (3) ◽  
pp. E276-E280 ◽  
Author(s):  
W. S. Evans ◽  
R. J. Krieg ◽  
E. R. Limber ◽  
D. L. Kaiser ◽  
M. O. Thorner

The effects of gender and the gonadal hormone environment on basal and stimulated growth hormone (GH) release by dispersed and continuously perifused rat anterior pituitary cells were examined. Cells from intact male and diestrus day 2 female rats and from castrate male rats either untreated or treated with testosterone (T) or 17 beta-estradiol (E2) were used. Basal GH release (ng/min per 10(7) cells; mean +/- SE) by cells from diestrus day 2 female rats was less than by cells from castrate rats treated with T (4.3 +/- 0.6 vs. 11.4 +/- 2.7, respectively; P less than 0.025). No other differences in basal release were detected. Concentration-response relationships were documented between human GH-releasing factor 40 (hGRF-40; 0.03-100 nM given as 2.5-min pulses every 27.5 min) and GH release. Mean (+/- SE) overall GH release (ng/min per 10(7) cells) above base line was greater by cells from intact male rats (496 +/- 92) than by cells from castrate (203 +/- 37.3; P less than 0.0001), castrate and T-treated (348 +/- 52.8; P = 0.008), or castrate and E2-treated (58.1 +/- 6.8; P less than 0.001) male rats or by diestrus day 2 rats (68.6 +/- 9.5; P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)


1972 ◽  
Vol 50 (10) ◽  
pp. 1014-1017
Author(s):  
Catherine L. Tanser ◽  
Nannie K. M. de Leeuw

The effect of human growth hormone (HGH) and human placental lactogen (HPL) on glucose consumption by erythrocytes and leucocytes in vitro was investigated. Glucose consumption was measured by determining glucose utilization during 3 h incubation at 37 °C, using the glucose oxidase method.HGH and HPL showed no effect on glucose consumption by erythrocytes, and HPL showed no effect on glucose consumption by leucocytes in vitro. Our results do not confirm previous reports of an inhibitory effect of HGH on glucose consumption by erythrocytes in vitro.


2018 ◽  
Vol 218 (1) ◽  
pp. 317-332 ◽  
Author(s):  
Li Qiang ◽  
Hong Cao ◽  
Jing Chen ◽  
Shaun G. Weller ◽  
Eugene W. Krueger ◽  
...  

The process by which tumor cells mechanically invade through surrounding stroma into peripheral tissues is an essential component of metastatic dissemination. The directed recruitment of the metalloproteinase MT1-MMP to invadopodia plays a critical role in this invasive process. Here, we provide mechanistic insight into MT1-MMP cytoplasmic tail binding protein 1 (MTCBP-1) with respect to invadopodia formation, matrix remodeling, and invasion by pancreatic tumor cells. MTCBP-1 localizes to invadopodia and interacts with MT1-MMP. We find that this interaction displaces MT1-MMP from invadopodia, thereby attenuating their number and function and reducing the capacity of tumor cells to degrade matrix. Further, we observe an inverse correlation between MTCBP-1 and MT1-MMP expression both in cultured cell lines and human pancreatic tumors. Consistently, MTCBP-1–expressing cells show decreased ability to invade in vitro and metastasize in vivo. These findings implicate MTCBP-1 as an inhibitor of the metastatic process.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
William J. Behof ◽  
Clayton A. Whitmore ◽  
Justin R. Haynes ◽  
Adam J. Rosenberg ◽  
Mohammed N. Tantawy ◽  
...  

AbstractErgothioneine (ERGO) is a rare amino acid mostly found in fungi, including mushrooms, with recognized antioxidant activity to protect tissues from damage by reactive oxygen species (ROS) components. Prior to this publication, the biodistribution of ERGO has been performed solely in vitro using extracted tissues. The aim of this study was to develop a feasible chemistry for the synthesis of an ERGO PET radioligand, [11C]ERGO, to facilitate in vivo study. The radioligand probe was synthesized with identical structure to ERGO by employing an orthogonal protection/deprotection approach. [11C]methylation of the precursor was performed via [11C]CH3OTf to provide [11C]ERGO radioligand. The [11C]ERGO was isolated by RP-HPLC with a molar activity of 690 TBq/mmol. To demonstrate the biodistribution of the radioligand, we administered approximately 37 MBq/0.1 mL in 5XFAD mice, a mouse model of Alzheimer’s disease via the tail vein. The distribution of ERGO in the brain was monitored using 90-min dynamic PET scans. The delivery and specific retention of [11C]ERGO in an LPS-mediated neuroinflammation mouse model was also demonstrated. For the pharmacokinetic study, the concentration of the compound in the serum started to decrease 10 min after injection while starting to distribute in other peripheral tissues. In particular, a significant amount of the compound was found in the eyes and small intestine. The radioligand was also distributed in several regions of the brain of 5XFAD mice, and the signal remained strong 30 min post-injection. This is the first time the biodistribution of this antioxidant and rare amino acid has been demonstrated in a preclinical mouse model in a highly sensitive and non-invasive manner.


2020 ◽  
Vol 11 ◽  
Author(s):  
Imran Hussain ◽  
Paromita Deb ◽  
Avisankar Chini ◽  
Monira Obaid ◽  
Arunoday Bhan ◽  
...  

HOXA5 is a homeobox-containing gene associated with the development of the lung, gastrointestinal tract, and vertebrae. Here, we investigate potential roles and the gene regulatory mechanism in HOXA5 in breast cancer cells. Our studies demonstrate that HOXA5 expression is elevated in breast cancer tissues and in estrogen receptor (ER)-positive breast cancer cells. HOXA5 expression is critical for breast cancer cell viability. Biochemical studies show that estradiol (E2) regulates HOXA5 gene expression in cultured breast cancer cells in vitro. HOXA5 expression is also upregulated in vivo in the mammary tissues of ovariectomized female rats. E2-induced HOXA5 expression is coordinated by ERs. Knockdown of either ERα or ERβ downregulated E2-induced HOXA5 expression. Additionally, ER co-regulators, including CBP/p300 (histone acetylases) and MLL-histone methylases (MLL2, MLL3), histone acetylation-, and H3K4 trimethylation levels are enriched at the HOXA5 promoter in present E2. In summary, our studies demonstrate that HOXA5 is overexpressed in breast cancer and is transcriptionally regulated via estradiol in breast cancer cells.


1991 ◽  
Vol 58 (4) ◽  
pp. 401-409 ◽  
Author(s):  
Thomas J. Hayden ◽  
Denise Brennan ◽  
Katherine Quirke ◽  
Paddie Murphy

SummaryXanthine oxidase/dehydrogenase (XO/XDH) increases at mid gestation in mammary gland but not in liver of the mouse and remains elevated until the pups are weaned at 20 d post partum. The increase in enzyme activity is due neither to alteration in activators or inhibitors nor to a production of a variant enzyme with altered catalytic properties. The increase is preceded in vivo by a surge of prolactin-like activity (placental lactogen) in plasma, and prolactin is required for induction of XO/XDH in explant culture in vitro. Induction of XO/XDH in vivo and in vitro precedes the full histological differentiation of the gland. In addition, induction of XO/XDH in vitro occurs more rapidly and at lower concentrations of prolactin than does histological differentiation. Thus although XO/XDH is present in milk, increased XO/XDH activity is an early event in mammogenesis in vivo and in vitro rather than a terminal component of differentiation.


1997 ◽  
Vol 185 (2) ◽  
pp. 273-280 ◽  
Author(s):  
Angela M. Hales ◽  
Coral G. Chamberlain ◽  
Christopher R. Murphy ◽  
John W. McAvoy

Cataract, already a major cause of visual impairment and blindness, is likely to become an increasing problem as the world population ages. In a previous study, we showed that transforming growth factor-β (TGFβ) induces rat lenses in culture to develop opacities and other changes that have many features of human subcapsular cataracts. Here we show that estrogen protects against cataract. Lenses from female rats are more resistant to TGFβ-induced cataract than those from males. Furthermore, lenses from ovariectomized females show increased sensitivity to the damaging effects of TGFβ and estrogen replacement in vivo, or exposure to estrogen in vitro, restores resistance. Sex-dependent and estrogen-related differences in susceptibility to cataract formation, consistent with a protective role for estrogen, have been noted in some epidemiological studies. The present study in the rat indicates that estrogen provides protection against cataract by countering the damaging effects of TGFβ. It also adds to an increasing body of evidence that hormone replacement therapy protects postmenopausal women against various diseases.


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