Plasma calcitonin, IGF-I levels and vertebral bone mineral density in hyperprolactinemic women during bromocriptine treatment

1993 ◽  
Vol 128 (5) ◽  
pp. 423-427 ◽  
Author(s):  
Ove Tørring ◽  
Bengt Isberg ◽  
Hans Erik Sjöberg ◽  
Elisabet Bucht ◽  
Anna Lena Hulting

Hyperprolactinemia is associated with decreased bone mineral density, which may be caused by the hypogonadism and hypoestrogenicity noticed in patients with hyperprolactinemia. Since calcitonin inhibits the bone resorption, and insulin-like growth factor I (IGF-I) has important anabolic effects on the skeleton, lack of one or both peptides may contribute to the development of osteopenia. We therefore measured the plasma calcitonin and IGF-I levels in nine women with hyperprolactinemia caused by a prolactin-producing pituitary tumor. The calcium-stimulated C-cell reactivity was studied by measuring calcitonin in plasma during a calcium clamp before and after normalization of serum prolactin during treatment with bromocriptine. Basal CT levels were measurable but lower than in healthy controls. Basal IGF-I levels and calcium-stimulated plasma calcitonin were normal in the hyperprolactinemic state and similar to the calcitonin and IGF-I levels during bromocriptine treatment. The serum prolactin levels decreased (p<0·001) and the serum estradiol levels increased (p<0·001). The bone mineral density of the lumbar spine increased significantly during treatment. Thus, basal plasma CT levels are slightly reduced in hyperprolactinemic women. However, the reversible osteopenia in hyperprolactinemic women is less likely to be caused by inhibited IGF-I secretion or by deficient CT levels since the CT response to calcium is normal. In addition, bromocriptine treatment with normalization of prolactin levels is beneficial for the bone mineral content in this condition.

2009 ◽  
Vol 10 (9) ◽  
pp. 1352-1358 ◽  
Author(s):  
Harold N. Rosen ◽  
Vicki Chen ◽  
Antonio Cittadini ◽  
Susan L. Greenspan ◽  
Pamela S. Douglas ◽  
...  

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Laurentiu Badescu ◽  
Oana Badulescu ◽  
Magda Badescu ◽  
Manuela Ciocoiu

The effects of polyphenols extracted fromSambucus nigrafruit were studied in streptozotocin- (STZ-) induced hyperglycemic rats to evaluate its possible antioxidant, anti-inflammatory, antiglycosylation activity, and antiosteoporosis effects in diabetes. DEXA bone mineral density tests were performed in order to determine bone mineral density (BMD), bone mineral content (BMC), and fat (%Fat) in control and diabetic animals, before and after polyphenol delivery. As compared to the normoglycemic group, the rats treated with STZ (60 mg/kg body weight) revealed a significant malondialdehyde (MDA) increase, as an index of the lipid peroxidation level, by 69%, while the total antioxidant activity (TAS) dropped by 36%, with a consistently significant decrease () in the activity of superoxide dismutase (SOD) and glutathione peroxidase (GPX). Also, the treatment of rats with STZ revealed a significant increase of IL-6, glycosylated haemoglobin (HbA1c), and osteopenia detected by DEXA bone mineral density tests. The recorded results highlight a significant improvement () in the antioxidative capacity of the serum in diabetic rats treated with natural polyphenols, bringing back to normal the concentration of reduced glutathione (GSH), as well as an important decrease in the serum concentration of MDA, with improved osteoporosis status. Knowing the effects of polyphenols could lead to the use of the polyphenolic extract ofSambucus nigraas a dietary supplement in diabetic osteoporosis.


2013 ◽  
Author(s):  
N Hangartner Thomas ◽  
F Short David ◽  
Gilsanz Vicente ◽  
J Kalkwarf Heidi ◽  
M Lappe Joan ◽  
...  

1996 ◽  
Vol 82 (1) ◽  
pp. 65-67 ◽  
Author(s):  
Sandro Barni ◽  
Paolo Lissoni ◽  
Gabriele Tancini ◽  
Antonio Ardizzoia ◽  
Marina Cazzaniga

In this study, the authors have analyzed the possible effects of one-year adjuvant treatment with tamoxifen on bone mineral density in postmenopausal breast cancer women. Bone mineral content was studied by photon absorptiometry (I-125), whereas bone balance was analyzed indirectly by serum PTH, osteocalcin, calcitonin, calcium and alkaline phosphatase levels. Bone mineral content and serum bone-related substances were measured before starting treatment and after one year. Results were analyzed using Student's t test for paired data. No difference was found between the two measurements for bone mineral content, PTH, calcitonin, calcium and alkaline phosphatase levels. Measurements at entry and after one year of treatment showed a statistically significant difference ( P < 0.001) only for osteocalcin. In accordance with other authors, we can conclude that treatment with tamoxifen does not cause an increase in menopausal bone resorption. The finding that osteocalcin levels decreased after one year of therapy with tamoxifen is interesting, but further studies are necessary to clarify the role of such levels in predicting a turnover of bone balance towards osteoblastic activity.


2011 ◽  
Vol 301 (6) ◽  
pp. E1191-E1197 ◽  
Author(s):  
Chandrasekhar Kesavan ◽  
Jon E. Wergedal ◽  
K.-H. William Lau ◽  
Subburaman Mohan

To establish a causal role for locally produced IGF-I in the mechanical strain response in the bone, we have generated mice with conditional disruption of the insulin-like growth factor (IGF) I gene in type 1α2 collagen-expressing cells using the Cre-loxP approach. At 10 wk of age, loads adjusted to account for bone size difference were applied via four-point bending or axial loading (AL) in mice. Two wk of bending and AL produced significant increases in bone mineral density and bone size at the middiaphysis of wild-type (WT), but not knockout (KO), mice. In addition, AL produced an 8–25% increase in trabecular parameters (bone volume-tissue volume ratio, trabecular thickness, and trabecular bone mineral density) at the secondary spongiosa of WT, but not KO, mice. Histomorphometric analysis at the trabecular site revealed that AL increased osteoid width by 60% and decreased tartrate-resistance acidic phosphatase-labeled surface by 50% in the WT, but not KO, mice. Consistent with the in vivo data, blockade of IGF-I action with inhibitory IGF-binding protein (IGFBP4) in vitro completely abolished the fluid flow stress-induced MC3T3-E1 cell proliferation. One-way ANOVA revealed that expression levels of EFNB1, EFNB2, EFNA2, EphB2, and NR4a3 were different in the loaded bones of WT vs. KO mice and may, in part, be responsible for the increase in bone response to loading in the WT mice. In conclusion, IGF-I expressed in type 1 collagen-producing bone cells is critical for converting mechanical signal to anabolic signal in bone, and other growth factors cannot compensate for the loss of local IGF-I.


2018 ◽  
Vol 3 (4) ◽  
pp. 62
Author(s):  
Jose Antonio ◽  
Anya Ellerbroek ◽  
Cassandra Carson

The effects of long-term high-protein consumption (i.e., >2.2 g/kg/day) are unclear as it relates to bone mineral content. Thus, the primary endpoint of this investigation was to determine if consuming a high-protein diet for one year affected various parameters of body composition in exercise-trained women. This investigation is a follow-up to a prior 6-month study. Subjects were instructed to consume a high-protein diet (>2.2 g/kg/day) for one year. Body composition was assessed via dual-energy X-ray absorptiometry (DXA). Subjects were instructed to keep a food diary (i.e., log their food ~three days per week for a year) via the mobile app MyFitnessPal®. Furthermore, a subset of subjects had their blood analyzed (i.e., basic metabolic panel). Subjects consumed a high-protein diet for one year (mean ± SD: 2.3 ± 1.1 grams per kilogram body weight daily [g/kg/day]). There were no significant changes for any measure of body composition over the course of the year (i.e., body weight, fat mass, lean body mass, percent fat, whole body bone mineral content, whole body T-score, whole body bone mineral density, lumbar bone mineral content, lumbar bone mineral density and lumbar T-score). In addition, we found no adverse effects on kidney function. Based on this 1-year within-subjects investigation, it is evident that a diet high in protein has no adverse effects on bone mineral density or kidney function.


2013 ◽  
Vol 5 (6) ◽  
Author(s):  
Homayoun Sheikholeslami ◽  
Majid Sotodeh ◽  
Amir Javadi ◽  
Neda Nasirian ◽  
Amir Mohammad Kazemifar ◽  
...  

2011 ◽  
pp. P1-343-P1-343
Author(s):  
Kathryn E Ackerman ◽  
Gary S Skrinar ◽  
Eva Medvedova ◽  
Madhusmita Misra ◽  
Karen K Miller

Sign in / Sign up

Export Citation Format

Share Document