The role of estrogen receptor-α and its activation function-1 for growth plate closure in female mice

High estradiol levels in late puberty induce growth plate closure and thereby cessation of growth in humans. In mice, the growth plates do not fuse after sexual maturation, but old mice display reduced longitudinal bone growth and high-dose estradiol treatment induces growth plate closure. Estrogen receptor (ER)-α stimulates gene transcription via two activation functions (AFs), AF-1 and AF-2. To evaluate the role of ERα and its AF-1 for age-dependent reduction in longitudinal bone growth and growth plate closure, female mice with inactivation of ERα (ERα−/−) or ERαAF-1 (ERαAF-10) were evaluated. Old (16- to 19-mo-old) female ERα−/− mice showed continued substantial longitudinal bone growth, resulting in longer bones (tibia: +8.3%, P < 0.01) associated with increased growth plate height (+18%, P < 0.05) compared with wild-type (WT) mice. In contrast, the longitudinal bone growth ceased in old ERαAF-10 mice (tibia: −4.9%, P < 0.01). Importantly, the proximal tibial growth plates were closed in all old ERαAF-10 mice while they were open in all WT mice. Growth plate closure was associated with a significantly altered balance between chondrocyte proliferation and apoptosis in the growth plate. In conclusion, old female ERα−/− mice display a prolonged and enhanced longitudinal bone growth associated with increased growth plate height, resembling the growth phenotype of patients with inactivating mutations in ERα or aromatase. In contrast, ERαAF-1 deletion results in a hyperactive ERα, altering the chondrocyte proliferation/apoptosis balance, leading to growth plate closure. This suggests that growth plate closure is induced by functions of ERα that do not require AF-1 and that ERαAF-1 opposes growth plate closure.

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DHEA Suppresses Longitudinal Bone Growth by Acting Directly at Growth Plate through Estrogen Receptors

Endocrinology ◽

10.1210/en.2010-0920 ◽

2011 ◽

Vol 152 (4) ◽

pp. 1423-1433 ◽

Cited By ~ 8

Author(s):

Hongzhi Sun ◽

Weijin Zang ◽

Bo Zhou ◽

Lin Xu ◽

Shufang Wu

Keyword(s):

Estrogen Receptor ◽

Growth Plate ◽

Bone Growth ◽

Nuclear Factor Κb ◽

Binding Activity ◽

Skeletal Maturation ◽

Chondrocyte Apoptosis ◽

Chondrocyte Proliferation ◽

Longitudinal Bone Growth ◽

Growth Plate Chondrocyte

Abstract Dehydroepiandrosterone (DHEA) is produced by the adrenal cortex and is the most abundant steroid in humans. Although in some physiological and pathological conditions the increased secretion of DHEA and its sulfated form is associated with accelerated growth rate and skeletal maturation, it is unclear whether DHEA can affect longitudinal bone growth and skeletal maturation by acting directly at the growth plate. In our study, DHEA suppressed metatarsal growth, growth plate chondrocyte proliferation, and hypertrophy/differentiation. In addition, DHEA increased the number of apoptotic chondrocytes in the growth plate. In cultured chondrocytes, DHEA reduced chondrocyte proliferation and induced apoptosis. The DHEA-induced inhibition of metatarsal growth and growth plate chondrocyte proliferation and hypertrophy/differentiation was nullified by culturing metatarsals with DHEA in the presence of ICI 182,780, an inhibitor of estrogen receptor, but not in the presence of Casodex, an inhibitor of androgen receptor. Lastly, nuclear factor-κB DNA binding activity was inhibited by the addition of DHEA in the medium of cultured chondrocyte. Our findings indicate that DHEA suppressed bone growth by acting directly at growth plate through estrogen receptor. Such growth inhibition is mediated by decreased chondrocyte proliferation and hypertrophy/differentiation and by increased chondrocyte apoptosis.

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Regulation of bone growth via ligand-specific activation of estrogen receptor alpha

Journal of Endocrinology ◽

10.1530/joe-16-0263 ◽

2017 ◽

Vol 232 (3) ◽

pp. 403-410 ◽

Cited By ~ 8

Author(s):

Maryam Iravani ◽

Marie Lagerquist ◽

Claes Ohlsson ◽

Lars Sävendahl

Keyword(s):

Estrogen Receptor ◽

Side Effects ◽

Growth Plate ◽

Bone Growth ◽

High Dose ◽

Tall Stature ◽

Plate Height ◽

Estrogenic Effects ◽

Increased Risk ◽

Risk Of Cancer

Estrogens are well known for their capacity to promote bone maturation and at high doses to induce growth plate closure and thereby stop further growth. High-dose estrogen treatment has therefore been used to limit growth in extremely tall girls. However, recent data suggest that this treatment may have severe side effects, including increased risk of cancer and reduced fertility. We hypothesized that estrogenic effects in bone are mediated via ERα signaling. Twelve-week-old ovariectomized female C57BL/6 mice were subcutaneously injected for 4 weeks with E2 or selective ERα (PPT) or ERβ (DPN) agonists. After killing, tibia and femur lengths were measured, and growth plate morphology was analyzed. E2- and PPT-treated mice had shorter tibiae and femur bones when compared to vehicle-treated controls, whereas animals treated with DPN had similar bone lengths compared to controls. Growth plate height and hypertrophic zone height were reduced in animals treated with E2 or PPT but not in those treated with DPN, supporting that the effect was mediated via ERα. Moreover, PCNA staining revealed suppressed proliferation of chondrocytes in the tibia growth plate in PPT- or E2-treated mice compared to controls. Our data show that estrogenic effects on bone growth and growth plate maturation are mainly mediated via ERα. Our findings may have direct implications for the development of new and more selective treatment modalities of extreme tall stature using selective estrogen receptor modulators that may have low side effects than high-dose E2 treatment.

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The role of estrogen receptor α in growth plate cartilage for longitudinal bone growth

Journal of Bone and Mineral Research ◽

10.1002/jbmr.156 ◽

2010 ◽

Vol 25 (12) ◽

pp. 2690-2700 ◽

Cited By ~ 51

Author(s):

Anna E Börjesson ◽

Marie K Lagerquist ◽

Chen Liu ◽

Ruijin Shao ◽

Sara H Windahl ◽

...

Keyword(s):

Estrogen Receptor ◽

Growth Plate ◽

Bone Growth ◽

Estrogen Receptor Α ◽

Longitudinal Bone Growth ◽

Growth Plate Cartilage

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Estrogen receptor specificity in the regulation of the skeleton in female mice

Journal of Endocrinology ◽

10.1677/joe.0.1710229 ◽

2001 ◽

Vol 171 (2) ◽

pp. 229-236 ◽

Cited By ~ 140

Author(s):

MK Lindberg ◽

SL Alatalo ◽

JM Halleen ◽

S Mohan ◽

JA Gustafsson ◽

...

Keyword(s):

Estrogen Receptor ◽

Estrogen Receptor Alpha ◽

Bone Growth ◽

Fat Content ◽

Mineral Density ◽

Trabecular Bone Mineral Density ◽

Longitudinal Bone Growth ◽

Female Mice ◽

Opposing Effects ◽

Er Alpha

There are two known estrogen receptors, estrogen receptor-alpha (ER alpha) and estrogen receptor-beta (ER beta), which may mediate the actions of estrogen. The aim of the present study was to compare fat content, skeletal growth and adult bone metabolism in female mice lacking ER alpha (ERKO), ER beta (BERKO) or both ERs (DERKO). We demonstrate that endogenous estrogens decrease the fat content in female mice via ER alpha and not ER beta. Interestingly, the longitudinal bone growth was decreased in ERKO, increased in BERKO, but was intermediate in DERKO females, demonstrating that ER alpha and ER beta exert opposing effects in the regulation of longitudinal bone growth. The effects on longitudinal bone growth were correlated with similar effects on serum levels of IGF-I. A complex regulation of the trabecular bone mineral density (BMD), probably caused by a disturbed feedback regulation of estrogen and testosterone, was observed in female ER-inactivated mice. Nevertheless, a partial functional redundancy for ER alpha and ER beta in the maintenance of the trabecular BMD was observed in the female mice at 60 days of age. Thus, ER alpha and ER beta may have separate effects (regulation of fat), opposing effects (longitudinal bone growth) or partial redundant effects (trabecular BMD at 60 days of age), depending on which parameter is studied.

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Role of estrogen receptor signaling in skeletal response to leptin in female ob/ob mice

Journal of Endocrinology ◽

10.1530/joe-17-0103 ◽

2017 ◽

Vol 233 (3) ◽

pp. 357-367 ◽

Cited By ~ 6

Author(s):

Russell T Turner ◽

Kenneth A Philbrick ◽

Amida F Kuah ◽

Adam J Branscum ◽

Urszula T Iwaniec

Keyword(s):

Estrogen Receptor ◽

Cancellous Bone ◽

Bone Growth ◽

Volume Fraction ◽

Gonadal Hormones ◽

Uterine Weight ◽

Bone Formation Rate ◽

Longitudinal Bone Growth ◽

Gonadal Dysfunction

Leptin, critical in regulation of energy metabolism, is also important for normal bone growth, maturation and turnover. Compared to wild type (WT) mice, bone mass is lower in leptin-deficient ob/ob mice. Osteopenia in growing ob/ob mice is due to decreased bone accrual, and is associated with reduced longitudinal bone growth, impaired cancellous bone maturation and increased marrow adipose tissue (MAT). However, leptin deficiency also results in gonadal dysfunction, disrupting production of gonadal hormones which regulate bone growth and turnover. The present study evaluated the role of increased estrogen in mediating the effects of leptin on bone in ob/ob mice. Three-month-old female ob/ob mice were randomized into one of the 3 groups: (1) ob/ob + vehicle (veh), (2) ob/ob + leptin (leptin) or (3) ob/ob + leptin and the potent estrogen receptor antagonist ICI 182,780 (leptin + ICI). Age-matched WT mice received vehicle. Leptin (40 µg/mouse, daily) and ICI (10 µg/mouse, 2×/week) were administered by subcutaneous injection for 1 month and bone analyzed by X-ray absorptiometry, microcomputed tomography and static and dynamic histomorphometry. Uterine weight did not differ between ob/ob mice and ob/ob mice receiving leptin + ICI, indicating that ICI successfully blocked the uterine response to leptin-induced increases in estrogen levels. Compared to leptin-treated ob/ob mice, ob/ob mice receiving leptin + ICI had lower uterine weight; did not differ in weight loss, MAT or bone formation rate; and had higher longitudinal bone growth rate and cancellous bone volume fraction. We conclude that increased estrogen signaling following leptin treatment is dispensable for the positive actions of leptin on bone and may attenuate leptin-induced bone growth.

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Nuclear Factor-κB p65 Facilitates Longitudinal Bone Growth by Inducing Growth Plate Chondrocyte Proliferation and Differentiation and by Preventing Apoptosis

Journal of Biological Chemistry ◽

10.1074/jbc.m702991200 ◽

2007 ◽

Vol 282 (46) ◽

pp. 33698-33706 ◽

Cited By ~ 46

Author(s):

Shufang Wu ◽

Janna K. Flint ◽

Geoffrey Rezvani ◽

Francesco De Luca

Keyword(s):

Growth Plate ◽

Bone Growth ◽

Chondrocyte Apoptosis ◽

Pyrrolidine Dithiocarbamate ◽

Growth Plate Chondrocytes ◽

Chondrocyte Proliferation ◽

Longitudinal Bone Growth ◽

Metatarsal Bones ◽

Proliferation And Differentiation ◽

Cultured Chondrocytes

NF-κB is a group of transcription factors involved in cell proliferation, differentiation, and apoptosis. Mice deficient in the NF-κB subunits p50 and p52 have retarded growth, suggesting that NF-κB is involved in bone growth. Yet, it is not clear whether the reduced bone growth of these mice depends on the lack of NF-κB activity in growth plate chondrocytes. Using cultured rat metatarsal bones and isolated growth plate chondrocytes, we studied the effects of two NF-κB inhibitors (pyrrolidine dithiocarbamate (PDTC) or BAY11-7082 (BAY)), p65 short interference RNA (siRNA), and of the overexpression of p65 on chondrocyte proliferation, differentiation, and apoptosis. To further define the underlying mechanisms, we studied the functional interaction between NF-κB p65 and BMP-2 in chondrocytes. PDTC and BAY suppressed metatarsal linear growth. Such growth inhibition resulted from decreased chondrocyte proliferation and differentiation and from increased chondrocyte apoptosis. In cultured chondrocytes, the inhibition of NF-κB p65 activation (by PDTC and BAY) and expression (by p65 siRNA) led to the same findings observed in cultured metatarsal bones. In contrast, overexpression of p65 in cultured chondrocytes induced chondrocyte proliferation and differentiation and prevented apoptosis. Although PDTC, BAY, and p65 siRNA reduced the expression of BMP-2 in cultured growth plate chondrocytes, the overexpression of p65 increased it. The addition of Noggin, a BMP-2 antagonist, neutralized the stimulatory effects of p65 on chondrocyte proliferation and differentiation, as well as its anti-apoptotic effect. In conclusion, our findings indicate that NF-κB p65 expressed in growth plate chondrocytes facilitates growth plate chondrogenesis and longitudinal bone growth by inducing BMP-2 expression and activity.

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Role of Cholesterol in the Regulation of Growth Plate Chondrogenesis and Longitudinal Bone Growth

Journal of Biological Chemistry ◽

10.1074/jbc.m305518200 ◽

2003 ◽

Vol 279 (6) ◽

pp. 4642-4647 ◽

Cited By ~ 37

Author(s):

Shufang Wu ◽

Francesco De Luca

Keyword(s):

Growth Plate ◽

Bone Growth ◽

Longitudinal Bone Growth ◽

Regulation Of Growth

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The Role of the Growth Plate in Longitudinal Bone Growth

Poultry Science ◽

10.3382/ps.0701806 ◽

1991 ◽

Vol 70 (8) ◽

pp. 1806-1814 ◽

Cited By ~ 46

Author(s):

M. PINES ◽

S. HURWITZ

Keyword(s):

Growth Plate ◽

Bone Growth ◽

Longitudinal Bone Growth

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Glycogen synthase kinase 3 alpha/beta deletion induces precocious growth plate remodeling and cell loss in mice

10.1101/2020.04.04.025700 ◽

2020 ◽

Author(s):

Supinder Kour Bali ◽

Dawn Bryce ◽

Carina Prein ◽

James R. Woodgett ◽

Frank Beier

Keyword(s):

Articular Cartilage ◽

Growth Plate ◽

Bone Growth ◽

Glycogen Synthase ◽

Final Height ◽

Glycogen Synthase Kinase ◽

Metabolic Phenotype ◽

Endochondral Bone ◽

Growth Plates

ABSTRACTGlycogen synthase kinase (GSK) 3 acts to negatively regulate multiple signaling pathways, including canonical Wnt signaling. The two mammalian GSK3 proteins (alpha and beta) are at least partially redundant. While Gsk3a KO mice are viable and display a metabolic phenotype, abnormal neuronal development and accelerated aging, Gsk3b KO animals die late in embryogenesis or at birth. Selective Gsk3b KO in bone delayed development of some bones, whereas cartilage-specific Gsk3b KO mice are normal except for elevated levels of GSK3alpha protein. However, the collective role of these two GSK3 proteins in cartilage was not evaluated. To address this, we generated tamoxifen-inducible, cartilage-specific Gsk3a/Gsk3b KO in juvenile mice and investigated their skeletal phenotypes. We found that cartilage-specific Gsk3a/Gsk3b deletion in young, skeletally immature mice causes precocious growth plate remodeling, culminating in shorter long bones and hence, growth retardation. These mice exhibit inefficient breathing patterns at later stages and fail to survive. The disrupted growth plates in KO mice showed progressive loss of cellular and proteoglycan components and Sox9 positive cells, with increased staining for osteocalcin and type II collagen. In addition, an increase in osteoclast recruitment and cell apoptosis was observed in growth plates. Surprisingly, changes in articular cartilage of Gsk3a/Gsk3b KO mice were mild compared to growth plates, signifying differential regulation of articular cartilage vs growth plate tissues. Taken together, these findings emphasize a crucial role of two GSK3 proteins in skeletal development, in particular in the maintenance and function of growth plates.SignificanceGrowth plate cartilage dynamics determine the rate of endochondral bone growth and thus, our final height. These processes are disturbed in many genetic and acquired diseases, but the intracellular mechanisms responsible for normal growth plate function, as well as the cessation of growth plate activity in puberty, are poorly understood. Here, we demonstrate that specific removal of both GSK3 genes (Gsk3a and Gsk3b) in postnatal cartilage of mice leads to a severe reduction of endochondral bone growth, premature remodelling of the growth plate, and early death. In contrast, articular cartilage is only mildly affected by deletion of both genes. These studies identify GSK3 signaling as a key regulator of growth plate dynamics and endochondral bone growth.

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