Prospective trial of oestrogen and calcium in postmenopausal women.

Horsman, A.; Gallagher, J. Christopher; Simpson, Margaret; Nordin, B. E. C.

doi:10.1136/bmj.2.6090.789

Cited by 342 publications

(74 citation statements)

References 2 publications

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“…This observation supports the general concept that estrogen inhibits bone resorption in vivo (2,3,22,24,28,(35)(36)(37)(38), although in vitro studies showed OVX rats that were infused with 17,3E2 (C and F). Fourteen days after ovariectomy, rats were infused with PBS or 1 nM 1713E2 into the metaphyseal region of the femur for 8 days, 24 ,ul/day.…”

Section: Discussionsupporting

confidence: 69%

“…A major unanswered question is whether estrogen action on bone in vivo is direct or indirect (4,(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41). It has been suggested that in vivo estrogen promotes the systemic production of growth factors, so-called estromedins, or the removal of growth inhibitors, estrocolyons, elsewhere in the body (42).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Direct effects of 17 beta-estradiol on trabecular bone in ovariectomized rats.

Takano‐Yamamoto

Rodan

1990

Proc. Natl. Acad. Sci. U.S.A.

163

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High-affinity nuclear binding sites for 17 (3-estradiol (17(3E2) were recently found in bone cells; however, the mechanism by which estrogen exerts its effect on bone in vivo is still unknown. To study if estrogen acts on bone directly, we used an experimental model in which test substances are infused locally into rat femur trabecular bone. SpragueDawley rats weighing 150-160 g were ovariectomized (OVX) and 14 days later a polyethylene tube (1 mm in diameter) connected to an Alzet osmotic minipump was implanted into the distal femur 9 mm from the joint. 17fiE2 (24 pl/day at 0.01-1 nM), 17a-estradiol (17aE2) (24 pl/day at 1 nM), or phosphatebuffered saline (NaCl, 8 g/liter; KCI, 0.2 g/liter; KH2PO4, 0.2 g/liter; Na2HPO4-7H2O, 2.16 g/liter) was infused for 8 days.The contralateral limb remained intact. Animals were sacrificed and bones were examined by histomorphometry. Ovariectomy caused a 50% loss in trabecular bone volume (TBV) in the secondary spongiosa (from 20.3% ± 1.7% to 9.6% + 1.1%; mean ± SEM), a 2-fold increase in osteoclast number (to 4.0 ± 0.4 per mm), a 3-fold increase in relative resorption surfaces (to 24.8% ± 2.9%), a 9-fold increase in osteoblast number (to 11.3 ± 2.1 per mm), and an 8-fold increase in relative osteoid surface (to 9.6% ± 1.7%). The local infusion of 17fiE2 for 8 days into OVX rats (t) restored the TBV dose dependently to 75% and 85% of control (non-OVX) levels, at 0.1 nM and 1 nM 17(3E2, respectively; (it) decreased osteoclast number and the relative resorption surface to control (non-OVX) levels; and (iii) further increased osteoblast number and the relative osteoid surface dose dependently (by 5-fold at 1 nM 173E2). Phosphate-buffered saline infusion was without effect.Infusion of 17ciE2 had no effect on TBV, osteoclast number, or resorption surface but increased slightly the osteoblast number and the osteoid surface. Its potency was 1/100 that of 1713E2. The local infusion of 17fiE2 or 17aE2 had no effect on body or uterine weight. We conclude from these rmdings that estrogen delivered directly to the bone of OVX rats in vivo at 2.4 and 24 fmol/day acted locally to inhibit bone resorption and stimulate bone formation.About 50 years ago, Albright et al.(1) suggested a link between postmenopausal osteoporosis and estrogen deficiency. The lack of estrogen is associated with increased bone remodeling rates, accelerated bone loss, and a negative calcium balance (2). Estrogen replacement therapy decreases bone turnover and the rate ofbone resorption and reduces the occurrence of fractures in postmenopausal osteoporosis. However, the mechanism by which estrogen exerts its effects on bone is still unknown (3,4 2172The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

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Section: Discussionsupporting

confidence: 69%

Section: Discussionmentioning

confidence: 99%

Direct effects of 17 beta-estradiol on trabecular bone in ovariectomized rats.

Takano‐Yamamoto

Rodan

1990

Proc. Natl. Acad. Sci. U.S.A.

163

View full text Add to dashboard Cite

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“…This possibility has been supported by diverse evidence, including the inverse relationship between osteoarthritis and osteoporosis (6,7). Indeed, this inverse relationship has prompted the hypothesis that since estrogen replacement therapy protects against bone loss after menopause (2,(8)(9)(10)(11)(12)(13)(14), then estrogen therapy should also result in relatively higher bone mass and relatively stiffer bone. In theory, estrogen use could produce osteoarthritis by increasing bony stiffness, and, rather than deforming with weight-bearing, this stiff subchondral bone may transmit more force to the overlying cartilage, leading to cartilage damage (5).…”

mentioning

confidence: 99%

Estrogen use and radiographic osteoarthritis of the knee in women

Hannan

Felson

Anderson

et al. 1990

Arthritis & Rheumatism

169

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Female participants of the Framingham Osteoarthritis Study (n = 831, mean age 73, age range 63-93)were evaluated for osteoarthritis with weight-bearing radiographs of the knee during 1983-1985. At each biennial examination (1963-1981), the women were asked about their use of estrogen during the previous 2 years. We categorized estrogen use as no use reported, use reported at 1 examination, or use reported at 2 or more examinations. We found no positive association of estrogen use with radiographic knee osteoarthritis after controlling for age, body mass index, age at menopause, physical activity, history of knee injury, and smoking. In fact, a modest but nonsignificant protective effect for both radiographic osteoarthritis (odds ratio 0.71, 95% confidence interval 0.42, 1.20) and severe radiographic osteoarthritis (odds ratio 0.66, 95% confidence interval 0.33, 1.32) was seen in women who reported estrogen use at 2 or more examinations. Subgroup analyses also showed no association between estrogen use and radiographic knee osteoarthritis. We conclude that es- Submitted for publication March 13, 1989; accepted in revised form November 6, 1989. trogen use in women is not associated with an increased risk of radiographic knee osteoarthritis.

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“…The mineralization of the skeleton undeniably decreases with age [22], and low BMD has been linked to an increased risk of fracture in elderly men and women [23][24][25][26][27][28][29], as well as in very elderly women [30,31]. Calcium supplementation has been shown to reduce the loss of bone [32], and increased consumption of calcium-rich dairy products (e.g., milk) has been found to provide an adequate source of dietary calcium, comparable to the results of other calcium supplementation strategies [33]. Even so, the association between dairy product consumption and bone health in elderly adults has not been firmly established [4,[7][8][9]34], and further investigation is warranted.…”

Section: Discussionmentioning

confidence: 99%

Dairy product intake and bone properties in 70-year-old men and women

et al. 2018

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Summary In the present population-based study including 70-year-old men and women, total dairy product intake was associated with a weak positive association with tibia trabecular and cortical cross-sectional areas. Purpose Milk consumption has recently been suggested to increase fracture risk. Therefore, we aimed to investigate associations between dairy product consumption and peripheral bone properties. Furthermore, we explored whether consumption of milk and fermented dairy products affected bone properties differently. Methods The Healthy Aging Initiative is a population-based, cross-sectional study investigating the health of 70-year-old men and women. Out of the 2904 individuals who met the inclusion criteria, data on self-reported daily dairy product consumption (dl/ day), peripheral quantitative computed tomography (pQCT) examinations at the 4 and 66% scan sites of the tibia and radius, and dual-energy X-ray absorptiometry (DXA) scans were collected from 2040 participants. Associations between dairy product consumption and bone properties were examined using multiple linear regression models adjusted for sex, muscle area, meal size, dietary protein proportion, current smoking status, and objectively measured physical activity. Results Total dairy product intake was associated with larger trabecular (2.296 (95% CI, 0.552-4.039) mm 2 , per dl/day increase, p = 0.01) and cortical cross-sectional areas (CSAs) in the tibia (1.757 (95% CI, 0.683-2.830 mm 2 , p = 0.001) as measured by pQCT and higher areal bone mineral density (aBMD) of the radius (3.231 (95% CI, 0.764-5.698) mg/cm 2 , p = 0.01) as measured by DXA. No other measurement in the tibia, radius, femoral neck, or lower spine was associated significantly with dairy product intake. Bone properties did not differ according to the type of dairy product consumed. Conclusion No evidence of a negative association between dairy product consumption and bone health was found. Furthermore, total dairy product consumption was associated with increased CSAs in the tibia, regardless of dairy product type. Collectively, our findings indicate the existence of a weak but significant positive association between dairy product consumption bone properties in older adults.

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Prospective trial of oestrogen and calcium in postmenopausal women.

Cited by 342 publications

References 2 publications

Direct effects of 17 beta-estradiol on trabecular bone in ovariectomized rats.

Direct effects of 17 beta-estradiol on trabecular bone in ovariectomized rats.

Estrogen use and radiographic osteoarthritis of the knee in women

Dairy product intake and bone properties in 70-year-old men and women

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