cholecalciferol and Weight-Loss

Observational studies suggest that blood concentrations of 25-hydroxyvitamin D [25(OH)D] are associated with morbidity, viral suppression, and mortality among adults living with HIV.. We evaluated the effect of cholecalciferol (vitamin D3) supplementation on the risk of HIV disease progression, HIV-1 viral suppression, comorbidities, weight change, and depression among HIV-infected individuals that were initiating antiretroviral therapy (ART) in Dar es Salaam, Tanzania.. We conducted a randomized, double-blind, placebo-controlled trial of vitamin D3 supplementation among 4000 HIV-infected adult men and nonpregnant women initiating ART with insufficient serum 25(OH)D concentrations (<30 ng/mL). Participants were randomly assigned to receive either weekly 50,000-IU doses for 4 wk followed by daily 2000 IU vitamin D3 until 1 y or a matching placebo regimen given in weekly followed by daily doses until 1 y. Participants were followed up at weekly visits for the first month followed by monthly visits thereafter. We conducted intent-to-treat analyses to assess the effect of vitamin D3 supplementation on the secondary trial outcomes of HIV progression or death, viral suppression, comorbidities, change in BMI, >10% weight loss, incident wasting, and depression.. During follow-up, 345 participants (17.2%) in the vitamin D3 group and 371 participants (18.6%) in the placebo group experienced HIV disease progression or death and there was no difference in risk between groups (RR: 0.91; 95% CI: 0.79, 1.06). Vitamin D3 supplementation did not affect the risk of an unsuppressed HIV-1 viral load (>1000 copies/mL) after 6 mo (RR: 1.10; 95% CI: 0.87, 1.41) and there was also no effect on change in BMI, risk of >10% weight loss, wasting, comorbidities, and depression (P values >0.05).. Vitamin D supplementation did not affect the risk of HIV progression, viral suppression, common morbidities, weight-related indicators, or depression among adults initiating ART in Tanzania.This trial was registered at clinicaltrials.gov as NCT01798680.

Topics: Adult; Cholecalciferol; Depression; Dietary Supplements; Disease Progression; Double-Blind Method; Female; HIV Infections; Humans; Male; Tanzania; Vitamin D; Weight Loss

Dysbiosis is related to changes in the composition and behaviour of intestinal microbiota, which may contribute to an age-related decline in metabolic and immune system functioning (immune-senescence).. The microbiota-targeted dietary and probiotic interventions have been shown to favorably affect the host health by an enhancement of antioxidant activity, improving immune homeostasis, suppression of chronic inflammation, regulation of metabolism and prevention of insulin resistance.. In our study, the use of specific probiotics strains improved the serum concentration of glycemic markers, thereby promoting better overall health.. Probiotics may help correct defects in the gut microbial environment improving metabolic parameters, such as blood sugar levels, glycosylated hemoglobin and a decrease in body weight.

Topics: Adult; Albania; Biomarkers; Blood Glucose; Cholecalciferol; Double-Blind Method; Dysbiosis; Female; Gastrointestinal Microbiome; Glycated Hemoglobin; Glycemic Control; Humans; Intestines; Italy; Lagerstroemia; Male; Middle Aged; Plant Extracts; Plant Leaves; Probiotics; Time Factors; Treatment Outcome; Weight Loss

The effects of higher than recommended vitamin D doses on bone mineral density (BMD) and quality are not known. In this study, higher intakes, in postmenopausal women undergoing weight control over 1 year, had no effect on areal or volumetric BMD but prevented the deterioration in cortical bone geometry.. Studies examining how bone responds to a standard dose of vitamin D supplementation have been inconsistent. In addition, the effects of higher doses on BMD and quality are not known. Postmenopausal women undergoing weight control to improve health outcomes are particularly at risk for bone loss and might benefit from supplemental vitamin D intake above the recommended allowance.. The decline in Ct thickness was prevented with higher vitamin D

Topics: Aged; Anthropometry; Body Composition; Body Weight; Bone Density; Bone Density Conservation Agents; Cholecalciferol; Diet, Reducing; Dietary Supplements; Dose-Response Relationship, Drug; Double-Blind Method; Exercise; Female; Humans; Middle Aged; Obesity; Osteoporosis, Postmenopausal; Postmenopause; Weight Loss

Bariatric patients often suffer from vitamin D deficiency (VDD), and both, morbid obesity and VDD, are related to non-alcoholic fatty liver disease. However, limited data are available regarding best strategies for treating VDD, particularly, in bariatric patients undergoing omega-loop gastric bypass (OLGB). Therefore, we examined the efficacy and safety of a forced vitamin D dosing regimen and intervention effects in liver fibrotic patients.. Compared with control group, higher increase of 25(OH)D (67.9 (21.1) vs. 55.7 nmol/L (21.1); p = 0.049) with lower prevalence of secondary hyperparathyroidism (10 vs. 24 %; p = 0.045) was observed in intervention group. No (serious) adverse events related to study medication were found. The loading dose regimen was more effective in increasing 25(OH)D in patients with significant liver fibrosis while this was not the case for conventional supplementation (placebo with maintenance dose) (71.5 (20.5) vs. 22.5 nmol/L (13.8); p = 0.022; n = 14).. Our findings indicate that a high vitamin D

Topics: Adult; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Gastric Bypass; Humans; Hyperparathyroidism, Secondary; Liver Cirrhosis; Male; Middle Aged; Non-alcoholic Fatty Liver Disease; Obesity, Morbid; Postoperative Period; Prevalence; Vitamin D; Vitamin D Deficiency; Vitamins; Weight Loss

The aim of the study was to compare the effects of vitamin D3 supplementation versus placebo on serum sex hormones in postmenopausal women completing a 12-month diet + exercise weight loss program.. Two hundred eighteen overweight or obese women (50-75 y) with serum 25-hydroxyvitamin D at least 10 to less than 32 ng/mL ("insufficient") were randomized to either weight loss + 2,000 IU/day oral vitamin D3, or to weight loss + daily placebo. Serum sex hormone-binding globulin, estrone, total, free, and bioavailable estradiol, and testosterone were measured by radioimmunoassay before randomization and at 12 months. Mean changes were compared between groups (intent-to-treat) using generalized estimating equations.. The 12-month changes in sex hormone-binding globulin, estrone, total, free, and bioavailable estradiol, and testosterone did not differ between groups (all P > 0.05). However, a greater increase in serum 25-hydroxyvitamin D was associated with a greater increase in sex hormone-binding globulin (Ptrend = 0.01), and larger decreases in free and bioavailable estradiol (Ptrend = 0.04, Ptrend = 0.03, respectively). In post-hoc analyses, we compared women randomized to vitamin D whose serum 25-hydroxyvitamin D remained insufficient (n = 38), to women who became replete (25-hydroxyvitamin D ≥32 ng/mL; n = 53). Replete women showed greater reductions in bioavailable estradiol (-1.8 vs -0.7 pg/mL), free testosterone (-0.8 vs -0.3 pg/mL), and bioavailable testosterone (-1.8 vs -0.6 ng/dL), and a greater increase in sex hormone-binding globulin (10.6 vs 4.7 nmol/L) (all P < 0.05), even after adjusting for differences in total 12-month weight loss.. Overall, 12-month changes in sex hormone did not differ between groups. However, vitamin D repletion was associated with greater reductions in sex hormones during weight loss, with a possible dose-dependent effect. Future studies should test higher doses and target circulating 25-hydroxyvitamin D levels when measuring such effects.

Topics: Aged; Cholecalciferol; Diet; Diet, Reducing; Dietary Supplements; Estradiol; Estrone; Exercise; Female; Gonadal Steroid Hormones; Humans; Middle Aged; Obesity; Overweight; Placebos; Postmenopause; Sex Hormone-Binding Globulin; Testosterone; Vitamin D; Vitamin D Deficiency; Weight Loss

Obesity and vitamin D deficiency are associated with risk for several cancers, possibly through inflammation and adipokine-related pathways. Two hundred and eighteen postmenopausal women with BMI > 25 kg/m(2) and low serum 25-hydroxyvitamin D (25(OH)D; ≥10-<32 ng/mL), were randomized to 12 months of either (i) weight-loss intervention + 2000 IU/day oral vitamin D3 or (ii) weight-loss intervention + daily placebo. Serum adiponectin, leptin, TNFα, IL6, IL1β, IL8, and IL10, were measured by immunoassay, and a composite inflammatory biomarker score calculated. Using generalized estimating equations, mean changes in outcomes were compared between arms (intent-to-treat), adjusted for possible confounders. Analyses were also stratified by weight-loss (gained/no weight-loss; <5%; 5% to 10%; ≥10%). At 12 months, there were no significant differences in analyte changes between arms. In stratified analyses, participants randomized to vitamin D3 who lost 5% to 10% of baseline weight, versus participants who gained weight/had no weight-loss, had significantly greater decreases in levels of IL6 compared with those randomized to placebo: absolute change -0.75 pg/mL (-17.2%), placebo versus -1.77 pg/mL (-37.3%), vitamin D, P = 0.004. Similar but attenuated results were observed for participants who lost ≥10% of baseline weight: -0.41 pg/mL (-13.6%), placebo versus -0.67 pg/mL (-17.3%), vitamin D, P = 0.02. Effects of vitamin D3 supplementation on levels of IL1β were inconsistent when stratified by weight loss. There were no intervention effects on IL10, TNFα, IL8, the composite score, adiponectin, or leptin, when stratified by weight-loss. In conclusion, vitamin D3 supplementation in combination with weight-loss of at least 5% of baseline weight was associated with significant reductions in levels of IL6.

Topics: Aged; Biomarkers; Cholecalciferol; Dietary Supplements; Female; Humans; Inflammation; Interleukin-6; Middle Aged; Obesity; Postmenopause; Weight Loss

Vitamin D deficiency is associated with obesity; whether repletion supports weight loss and changes obesity-related biomarkers is unknown.. We compared 12 mo of vitamin D3 supplementation with placebo on weight, body composition, insulin, and C-reactive protein (CRP) in postmenopausal women in a weight-loss intervention.. A total of 218 overweight/obese women (50-75 y of age) with serum 25-hydroxyvitamin D [25(OH)D] ≥10 ng/mL but <32 ng/mL were randomly assigned to weight loss + 2000 IU oral vitamin D3/d or weight loss + daily placebo. The weight-loss intervention included a reduced-calorie diet (10% weight loss goal) and 225 min/wk of moderate-to-vigorous aerobic activity. Mean 12-mo changes in weight, body composition, serum insulin, CRP, and 25(OH)D were compared between groups (intent-to-treat) by using generalized estimating equations.. A total of 86% of participants completed the 12-mo measurements. The mean (95% CI) change in 25(OH)D was 13.6 (11.6, 15.4) ng/mL in the vitamin D3 arm compared with -1.3 (-2.6, -0.3) ng/mL in the placebo arm (P < 0.0001). Changes in weight [-7.1 (-8.7, -5.7) compared with -7.4 (-8.1, -5.4) kg], body mass index (in kg/m(2): both -2.8), waist circumference [-4.9 (-6.7, -2.9) compared with -4.5 (-5.6, -2.6) cm], percentage body fat [-4.1 (-4.9, -2.9) compared with -3.5 (-4.5, -2.5)], trunk fat [-4.1 (-4.7, -3.0) compared with -3.7 (-4.3, -2.9) kg], insulin [-2.5 (-3.4, -1.7) compared with -2.4 (-3.3, -1.4) μU/mL], and CRP [-0.9 (-1.2, -0.6) compared with -0.79 (-0.9, -0.4) mg/L] [corrected] were similar between groups (all P > 0.05). Compared with women who achieved 25(OH)D <32 ng/mL, women randomly assigned to vitamin D who became replete (ie, 25(OH)D ≥32 ng/mL) lost more weight [-8.8 (-11.1, -6.9) compared with -5.6 (-7.2, -5.0) kg; P = 0.05], waist circumference [-6.6 (-9.3, -4.3) compared with -2.5 (-4.6, -2.0) cm; P = 0.02], and percentage body fat [-4.7 (-6.1, -3.5) compared with -2.6 (-3.9, -2.2); P = 0.04]. Among women with complete pill counts (97% adherence), the mean decrease in CRP was 1.18 mg/mL (46%) in the vitamin D arm compared with 0.46 mg/mL (25%) in the placebo arm (P = 0.03).. Vitamin D3 supplementation during weight loss did not increase weight loss or associated factors compared with placebo; however, women who became replete experienced greater improvements. This trial was registered at clinicaltrials.gov as NCT01240213.

Topics: Aged; Body Composition; Body Mass Index; Body Weight; C-Reactive Protein; Cholecalciferol; Diet; Dietary Supplements; Double-Blind Method; Energy Intake; Exercise; Female; Humans; Insulin; Linear Models; Middle Aged; Obesity; Patient Compliance; Postmenopause; Vitamin D Deficiency; Waist Circumference; Weight Loss

Weight loss (WL) is associated with a decrease in calcium absorption and may be one mechanism that induces bone loss with weight reduction.. Because vitamin D supplementation has been shown to increase true fractional calcium absorption (TFCA), the goal of this study was to examine the effect of vitamin D during WL or weight maintenance (WM).. A randomized, placebo-controlled, double-blind 6-wk study was conducted in 82 postmenopausal women [BMI (in kg/m(2); ±SD): 30.2 ± 3.7] with 25-hydroxyvitamin D [25(OH)D] concentrations <70 nmol/L during either WL or WM. All women were given 10 μg vitamin D(3)/d and 1.2 g Ca/d and either weekly vitamin D(3) (375 μg) or a placebo equivalent to 63 μg (2500 IU)/d and 10 μg (400 IU)/d, respectively. We measured TFCA with the use of dual-stable isotopes, 25(OH)D, parathyroid hormone, estradiol, calcitriol, and urinary calcium at baseline and 6 wk in weight loss and vitamin D(3)-supplementation (WL-D; n = 19), weight maintenance and vitamin D(3)-supplementation (WM-D; n = 20), weight loss and placebo (n = 22), and weight maintenance and placebo (n = 21) groups.. WL groups lost 3.8 ± 1.1% of weight with no difference between vitamin D(3) supplementation and the placebo. The rise in serum 25(OH)D was greatest in the WL-D group (19.8 ± 14.5 nmol/L) compared with in WM-D (9.1 ± 10.3 nmol/L) and placebo groups (1.5 ± 10.9 nmol/L). TFCA increased with vitamin D(3) supplementation compared with placebo treatment (P < 0.01) and decreased during WL compared with WM. Serum 25(OH)D or 1,25-dihyroxyvitamin D did not correlate with TFCA.. These data show that vitamin D supplementation increases TFCA and that WL decreases TFCA and suggest that, when calcium intake is 1.2 g/d, either 10 or 63 μg vitamin D/d is sufficient to maintain the calcium balance. This trial was registered at clinicaltrials.gov as NCT00473031.

Topics: Body Composition; Calcium, Dietary; Caloric Restriction; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Humans; Middle Aged; Parathyroid Hormone; Regression Analysis; Weight Loss

Investigate whether cholecalciferol supplementation leads to weight loss in overweight and obese adults.. Randomized double blind clinical trial with 20,000 IU cholecalciferol twice a week, or 20,000 IU once a week plus placebo, or placebo twice a week, for 12 months. All subjects were given 500 mg calcium supplementation.. Four hundred and forty five healthy, overweight, and obese men and women (age 21-70 years, body mass index (BMI) 28.0-47.0 kg/m(2)). Body weight, fatness, and fat distribution parameters were measured by dual-energy X-ray absorptiometry and anthropometry, blood samples and 24-h urinary samples were collected.. At baseline, there were no significant differences between the groups, but there was a significant inverse relation between serum 25-hydroxyvitamin D (25(OH)D) levels and BMI, and a significant positive association between calorie intake and BMI. Three hundred and thirty four subjects completed the study. During the study, there was no significant change in weight, waist-to-hip ratio (WHR) or percentage body fat in any of the groups, nor between them. Parathyroid hormone decreased and 25(OH)D increased significantly in both groups receiving cholecalciferol, and serum levels of 25(OH)D stabilized after 3 months. Serum calcium was unchanged in all groups. Urinary calcium excretion increased in all groups, but there was no significant difference between the groups. Weekly dosage of 20,000-40,000 IU cholecalciferol for 12 months was associated with a low risk of adverse effects, at least in overweight and obese adults living at latitude 70 degrees N.. Significant weight reduction in overweight and obese subjects is unlikely to occur with cholecalciferol supplementation.

Topics: Adult; Aged; Body Mass Index; Cholecalciferol; Dietary Supplements; Double-Blind Method; Female; Humans; Male; Middle Aged; Obesity; Overweight; Vitamin D; Weight Loss; Young Adult

Topics: Agammaglobulinemia; Autoimmune Diseases; Autoimmunity; B-Lymphocytes; Bacterial Infections; Calcium; Cholecalciferol; Electrolytes; Female; Humans; Hypocalcemia; Hypokalemia; Hypoparathyroidism; Hypophosphatemia; Immunoglobulins, Intravenous; Immunologic Deficiency Syndromes; Magnesium; Middle Aged; Thymoma; Weight Loss

To compare the effects of 12 months of vitamin D3 supplementation with that placebo on lean mass, bone mineral density (BMD), and muscle strength in overweight or obese postmenopausal women completing a structured weight-loss program.. Double-blind, placebo-controlled randomized clinical trial.. Fred Hutchinson Cancer Research Center, Seattle, Washington.. Postmenopausal women aged 50 to 75 with a body mass index (BMI) of 25 kg/m(2) or greater and a serum 25-hydroxyvitamin D (25(OH)D) concentration between 10.0 and 32.0 ng/mL (insufficient) (N = 218).. Oral vitamin D3 2,000 IU/d or placebo in combination with a lifestyle-based weight loss intervention consisting of a reduction of 500 kcal to 1,000 kcal per day and 225 min/wk of moderate- to vigorous-intensity aerobic exercise.. Serum 25(OH)D, body composition, and muscle strength were measured before randomization (baseline) and at 12 months. Mean changes of the groups were compared (intention to treat) using generalized estimating equations.. Change in 25(OH)D was significantly different between the vitamin D and placebo groups at 12 months (13.6 ng/mL vs -1.3 ng/mL, P < .001), but no differences in change in lean mass (-0.8 kg vs -1.1 kg, P = .53) or BMD of the spine (-0.01 g/cm(2) vs 0.0 g/cm(2) , P = .82) or right femoral neck (both -0.01 g/cm(2) , P = .49) were detected between the groups. Leg strength decreased in the vitamin D group but not in the placebo group (-2.6 pounds vs 1.8 pounds, P = .03). In women randomized to vitamin D, achieving repletion (25(OH)D ≥ 32 ng/mL) did not alter results.. Vitamin D3 supplementation during weight-loss decreased leg strength but did not alter changes in lean mass or BMD in postmenopausal women with vitamin D insufficiency.

Topics: Aged; Body Composition; Body Mass Index; Bone Density; Cholecalciferol; Double-Blind Method; Exercise; Female; Humans; Middle Aged; Muscle Strength; Muscle, Skeletal; Postmenopause; Washington; Weight Loss

Vitamin D deficiency affects more that 1 billion people worldwide. Although thought to increase risk of bacterial infections, the importance of vitamin D on host defense against intestinal bacterial pathogens is currently unclear since injection of the active form of vitamin D, 1,25(OH)2D3, increased susceptibility to the enteric bacterial pathogen Citrobacter rodentium by suppressing key immune/inflammatory factors. To further characterize the role of vitamin D during bacteria-induced colitis, we fed weanling mice either vitamin D3-deficient or vitamin D3-sufficient diets for 5 wk and then challenged them with C. rodentium. Vitamin D3-deficient mice lost significantly more body weight, carried higher C. rodentium burdens, and developed worsened histological damage. Vitamin D3-deficient mice also suffered greater bacterial translocation to extra-intestinal tissues, including mesenteric lymph nodes, spleen, and liver. Intestinal tissues of infected vitamin D3-deficient mice displayed increased inflammatory cell infiltrates as well as significantly higher gene transcript levels of inflammatory mediators TNF-α, IL-1β, IL-6, TGF-β, IL-17A, and IL-17F as well as the antimicrobial peptide REG3γ. Notably, these exaggerated inflammatory responses accelerated the loss of commensal microbes and were associated with an impaired ability to detoxify bacterial lipopolysaccharide. Overall, these studies show that dietary-induced vitamin D deficiency exacerbates intestinal inflammatory responses to infection, also impairing host defense.

Topics: Animals; Bacterial Load; Bacterial Translocation; Cecum; Cholecalciferol; Citrobacter rodentium; Colitis; Colon; Cytokines; Diet; Disease Models, Animal; Enterobacteriaceae Infections; Feces; Female; Host-Pathogen Interactions; Inflammation Mediators; Intestinal Mucosa; Lipopolysaccharide Receptors; Lipopolysaccharides; Mice, Inbred C57BL; Pancreatitis-Associated Proteins; Phosphorylation; Proteins; Time Factors; Vitamin D Deficiency; Weight Loss

Topics: Antitubercular Agents; Cholecalciferol; Dietary Supplements; Humans; Nutritional Status; Sputum; Tuberculosis, Pulmonary; Vitamins; Weight Loss

Topics: Adult; Arthralgia; Bone Density Conservation Agents; Calcium; Celiac Disease; Cholecalciferol; Diagnosis, Differential; Drug Therapy, Combination; Female; Fractures, Bone; Humans; Hyperparathyroidism, Secondary; Neoplasms; Obesity; Treatment Outcome; Weight Loss

Topics: Calcium, Dietary; Cholecalciferol; Dairy Products; Diet, Reducing; Energy Intake; Humans; Obesity; Weight Loss

Topics: Calcium, Dietary; Cholecalciferol; Dairy Products; Diet, Reducing; Energy Intake; Humans; Obesity; Weight Loss

The chronotherapeutic effects of 1-alpha-(OH) vitamin D3, a pro-drug of 1,25(OH)2 vitamin D3 (1,25(OH)2D3), were evaluated by repeated dosing of the drug in aged stroke-prone spontaneously hypertensive male rats, a model of osteoporosis. Animals (7 months old) were kept in rooms with a 12-h light/dark cycle. Drug (0.5 microg/kg) or vehicle was given once daily at 2 or 14 h after lights on for 3 months. The severity of adverse effects such as body weight loss, hypercalcemia and hyperphosphatemia was significantly less when the drug was given at 14 h after lights on (14 HALO). Serum 1,25(OH)2 vitamin D3 concentrations of 2 h after lights on (2 HALO) group and 14 HALO group did not differ significantly after dosing. The decrease in parathyroid hormone (PTH) level 12 weeks after the start of the study was greater in the 14 HALO group than in the 2 HALO group. Urinary excretion of inorganic Ca and P in the 2 HALO group was greater than that in the 14 HALO group. Urinary excretion of deoxypyridiniline, an index of the bone resorption capacity of osteoclasts, was much suppressed in the 14 HALO group, suggesting that the efficacy of vitamin D3 for suppressing bone resorption might vary with the dosing time. The increase in bone density of both femurs, determined by dual-energy X-ray absorption at the end of the study, was greater in the 14 HALO group than in the 2 HALO group. This is the first study to show the dosing time-dependent efficacy and toxicity of active vitamin D3 in an animal model of osteoporosis. These results indicate that a chronopharmacological approach is beneficial for establishing a more effective and/or safer regimen of active vitamin D3 for the treatment of osteoporosis.

Topics: Aging; Amino Acids; Animals; Body Weight; Bone Density; Calcium; Cholecalciferol; Chronotherapy; Disease Models, Animal; Hypercalcemia; Hypertension; Male; Osteoporosis; Parathyroid Hormone; Phosphates; Rats; Rats, Inbred SHR; Steroid Hydroxylases; Time Factors; Weight Loss

Bisphosphonates, potent inhibitors of bone resorption, have been used clinically to correct the continued loss of bone mass in osteoporosis and in other conditions. However, there has been some concern that long-term treatment with these compounds, as well as more recently developed drugs, may also decrease the rate of bone formation. Bisphosphonates, which are strongly bound to hydroxyapatite crystals, may alter the structure and reactivity of the crystals, interfere with new crystal nucleation and growth, as well as alter the short-range order of newly formed crystals. We have investigated the chemistry and structure of the solid calcium-phosphate mineral phase of lumbar vertebrae of ovariectomized, 6.5-month-old rats treated with bisphosphonates for 1 year after onset of osteopenia. Appropriate control groups were used for comparison. The techniques used to assess the mineral phase were chemical analyses, Fourier transform-infrared (FT-IR) and FT-Raman spectroscopy, FT-IR microspectroscopy, and phosphorus-31 magic-angle-sample spinning nuclear magnetic resonance spectroscopy ((31)P MAS NMR). The (31)P MAS NMR spectra of trabecular bone of lumbar vertebrae of control, ovariectomized, and treated animals were similar. However, there were several significant differences in the results obtained by FT-IR spectroscopy of the whole tissue samples, FT-IR microspectroscopy of sections of bone, and chemical analyses. For example, whereas chemical analyses demonstrated that the CO(3) content of the mineral phase of the ovariectomized animals was decreased compared with controls, FT-IR microspectroscopy of bone sections showed no changes in the relative CO(3) content, but some changes in the environment of the CO(3) groups. However, chemical analyses of the crystals, combined with data from all three spectroscopic methods and with data from serum analysis, did indicate small changes in the mineral phase after ovariectomy, corrected after treatment with bisphosphonates. In any event, the chemical and structural data in the present studies demonstrate that the bisphosphonate, tiludronate, does not significantly alter the mineral components of bone after 1 year of treatment during the course of which bone loss was reversed.

Topics: Animals; Apatites; Bone Diseases, Metabolic; Bone Resorption; Calcium; Cholecalciferol; Diphosphonates; Disease Models, Animal; Female; Lumbar Vertebrae; Magnetic Resonance Spectroscopy; Ovariectomy; Parathyroid Hormone; Phosphorus; Phosphorus Radioisotopes; Rats; Rats, Sprague-Dawley; Spectroscopy, Fourier Transform Infrared; Weight Loss

Glucocorticoid treatment causes osteoporosis and growth retardation in humans. Insulin-like growth factor I (IGF-I) stimulates differentiation and replication of cultured osteoblast-like cells and induces longitudinal bone growth in IGF-I-deficient rats. We investigated the influence of subcutaneously infused IGF-I on bone and mineral metabolism of male rats treated with a high dose of dexamethasone. Dexamethasone was added to the drinking water in a concentration of 1 mg/l. After 30 days of dexamethasone treatment, recombinant human IGF-I (300 micrograms/day) or solvent was infused sc by osmotic minipumps for 21 days while dexamethasone was continued. Age-matched untreated male rats served as healthy controls. Dexamethasone-treated rats lost weight. Their IGF-I levels were decreased to 36% of healthy controls. Infusion of IGF-I resulted in an increase in IGF-I serum levels (582% compared to healthy controls) and allowed some weight gain. Osteocalcin and calcitriol levels were markedly decreased in dexamethasone-treated rats and were not influenced significantly by IGF-I infusion. In contrast, IGF-I treatment restored the free calcitriol concentration (molar ratio of calcitriol to vitamin D-binding protein) towards normal. Furthermore, infusion of IGF-I partially corrected the dexamethasone-induced hyperinsulinemia. Histomorphometric analysis revealed no difference in vertebral trabecular bone density (i.e. growth-independent bone remodeling) between the three groups. In contrast, mean trabecular bone density in tibial metaphyses was increased markedly by dexamethasone, presumably due to osteoclast inhibition. Insulin-like growth factor I infusion did not significantly influence these structural metaphyseal bone parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Alkaline Phosphatase; Animals; Blood Glucose; Bone and Bones; Bone Density; Calcitriol; Cholecalciferol; Dexamethasone; Drug Interactions; Humans; Insulin; Insulin-Like Growth Factor I; Male; Minerals; Osteocalcin; Rats; Recombinant Proteins; Vitamin D-Binding Protein; Weight Loss