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Evaluation of vertical accelerations measured at the hip during common exercises and daily life in premenopausal womenDave, Nirmal 09 September 2016 (has links)
Raw acceleration can be used as a proxy measure representing external forces experienced at the hip. Peak vertical acceleration at the hip was measured (ActiGraph GT3X+ - BT) in 30 premenopausal women during common exercises (walking, running, stairs and jumping) and while they went about their normal routine (7 days). Accelerations experienced during running and jumping activities were consistently ≥3.2g, whereas only accelerations during box jumps were greater than the higher recommended threshold of ≥ 4.9g proposed to improve bone mineral density in premenopausal women. Peak jerk experienced during jumping activities was greater than the recommended threshold of 100g/s. The median number of accelerations/day ≥3.2g was 30.4, whereas only 3.5 incidences/day were observed at ≥4.9g. Running and jumping resulted in vertical accelerations that met or exceeded the thresholds proposed to be beneficial for bone, however, participants rarely experienced high magnitude vertical accelerations during daily life. / October 2016
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Vitamin D status in winter and summer among nurses and implications for cancer etiologyWALLINGFORD, SARAH 23 September 2009 (has links)
Background: Recent research indicates that inadequate vitamin D status may incur increased cancer risk, particularly for breast and colon cancer. Cutaneous generation of vitamin D through direct absorption of summer sunlight is considered the principal source of vitamin D; however, at latitudes above 40ºN, UVB rays are insufficient to permit cutaneous synthesis during winter. Vitamin D can also be obtained from natural and fortified dietary sources and through supplement use, although dietary reference intake values do not seem to compensate for restricted cutaneous synthesis in winter.
Objectives: To determine the prevalence of vitamin D insufficiency post-winter and post-summer, to determine the seasonal variation in 25-hydroxyvitamin D (25(OH)D) levels, and to investigate determinants of 25(OH)D concentrations.
Methods: A cross-sectional study of vitamin D status post-winter and post-summer was conducted among 49 premenopausal rotating shift nurses at Kingston General Hospital. In each season, vitamin D levels were measured using a radioimmunoassay to quantify serum 25(OH)D from fasting blood samples, and personal, lifestyle, and dietary factors potentially influencing vitamin D levels were assessed from a self-report questionnaire. Nurses were classified as vitamin D sufficient (>30ng/mL) or insufficient (≤30ng/mL).
Results: A statistically significant difference was found between mean serum 25(OH)D concentrations post-winter (32.6ng/mL) and post-summer (42.5ng/mL) (p=0.0003). The prevalence of vitamin D insufficiency post-winter was 49% compared to 24% post-summer p=0.02). Tanning bed use was associated with significantly higher winter serum 25(OH)D levels was tanning bed, while controlling for age, BMI, and vitamin D-fortified yogurt consumption (R2=0.41, p=0.007). For summer, predictors of higher serum 25(OH)D levels were supplement use and tanning bed use in the past six months, while controlling for age, BMI, and beef/veal consumption (R2=0.53, p=0.001).
Conclusions: Vitamin D insufficiency was prevalent both post-winter and post-summer, but with much higher prevalence post-winter. Controlling for age and BMI, tanning bed use was a determinant of serum 25(OH)D concentrations in both seasons, while fortified yogurt consumption also contributed in winter, and beef/veal consumption and supplement use contributed in summer. These findings support the need to improve vitamin D status among this population, and to increase the dietary reference intake values and supplement recommendations. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2009-09-22 15:35:27.652
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Bone Health Education for Osteoporosis Risk Reduction in Premenopausal Women: A Quality Improvement ProjectNichols, Gloria Nichols 01 January 2016 (has links)
In the United States, about 8.5 million women live with osteoporosis. Osteoporosis is a debilitating systemic skeletal disorder characterized by low bone mass and reduced bone mineral density that occurs with the loss of estrogen. The mortality rate for this group is about 3 to 4 times higher than other women and as many as 1 in 3 experience a fracture. Guided by the Health Belief Model, this project evaluated how a bone health fact sheet impacts knowledge about osteoporosis and self-efficacy for preventative behavioral change in premenopausal women (age 40-58 years). The project also evaluated if an electronic medical record (EMR) alert system with an additional bone health education in the patient instruction menu can improve participation by 11 health care providers (HCPs). Prior to the participants receiving the fact sheet, the knowledge, health beliefs, and perceived risks for developing osteoporosis were measured using the Revised Osteoporosis Knowledge Test (ROKT) and the Osteoporosis Health Belief Scale (OHBS). Although 87% of participants identified menopause as a major osteoporosis risk factor, fewer women (33%) knew that surgical removal of the ovaries was also a risk factor and half agreed or strongly agreed that calcium and exercise can prevent osteoporosis. After receiving the fact sheet, the participants had an average confidence score of 62% on the Osteoporosis Self-Efficacy Scale (OSES) for engaging in exercise and an average confidence score of 65% for adhering to calcium intake guidelines. Furthermore, the EMR alert system facilitated 100% documentation by HCPs. These results indicated the fact sheet can motivate premenopausal women to engage in osteoporosis preventive behaviors. Importantly, the EMR reminder with education fact sheet can facilitate the active involvement of HCPs in patient education.
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Relationship Between Total Body Mass, Fat-Free Mass, Fat Mass, and Bone Mineral Density of the Hip In Middle-Age Women: The Roles of Diet, Physical Activity, and MenopauseFosson, Elizabeth Reid 31 July 2012 (has links) (PDF)
Objective: This study was conducted to investigate the relationship between hip bone mineral density (BMD), fat free mass (FFM), fat mass (FM), and total body mass (TBM) and the extent to which these relationships were modified by various confounding factors. The cross-sectional analysis included 262 healthy females (mean age 41.6±3.0 years). Methods: BMD of the hip and body composition were assessed by the Hologic 4500W dual energy x-ray absorptiometry (DXA) system. Total and intensity of physical activity (PA) were objectively measured using an Actigraph accelerometer. Dietary calcium and vitamin D from food and beverages, as well as from supplements, were measured separately using the Block food frequency questionnaire. Menopause status and prescription bone drug use were measured by a questionnaire. Results: The relationship between FFM and hip BMD was strong and robust (F=24.5, P<0.0001). Using the pooled standard deviation revealed a large effect size of 1.2 when comparing hip BMD of women with low FFM and high FFM. Potentially confounding variables, considered individually and collectively, did not change this relationship. The association between FM and hip BMD was also substantial (F=9.9, P<0.0001) and remained significant when controlling for all potentially confounding variables, except differences in FFM. The relationship between TBM and hip BMD was also strong and dose-response (F=21.5, P<0.0001) and remained significant, except when differences in FFM were controlled. Conclusion: The relationships between body mass (total, fat, and fat free) and BMD of the hip in middle-age women are strong and significant. The associations are not influenced by differences in age, height, menopause status, calcium or vitamin D intake, volume or intensity of PA, or the use of bone enhancing prescription drugs. The findings suggest that women with low body mass, particularly low FFM, tend to have low hip BMD and there is little that can be done to change this association.
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A Description of BMI and the Incidence of Breast Cancer in the Premenopausal WomanCarter, Sue A. 20 April 2015 (has links)
No description available.
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Effects of Endogenous and Exogenous Hormones on the Female Breast : With Special Reference to the Expression of ProteoglycansHallberg, Gunilla January 2011 (has links)
This thesis aims to study the effects of endogenous and exogenous hormones and mammographic breast density (BD) on cellular markers in non-cancerous female breast tissue. Women on the waiting list for breast reduction plastic surgery were recruited (n = 79), and randomized to 2 months of hormone therapy or no therapy before surgery. The women had a mammogram and a needle biopsy 2 months before surgery and tissue samples were obtained at the operation. In premenopausal women, estrogen receptor (ER)α levels were associated with age (p = 0.0002), were similar in the follicular and luteal phases of the menstrual cycle and were higher in parous than in nulliparous women (p = 0.009). Current smokers had lower PR levels than non-smokers (p = 0.019). Women on oral contraception had lower ERα (p = 0.048) and PR (p = 0.007) levels than women in the follicular phase. The ERα levels did not differ significantly between postmenopausal estrogen and estrogen-progestogen users, but PR levels were lower among estrogen-progestogen users (p = 0.03). We found lower expression of the genes for decorin and syndecans 1 and 4 in the luteal phase than in the follicular phase, among parous women. Protein levels of the androgen receptor, syndecan-4 and decorin was lower in premenopausal women who were using oral contraceptives (OC) than in those in the follicular phase (p = 0.002 - 0.02), whereas no significant differences between OC use and the luteal phase were found. In premenopausal women, BD was negatively associated with age and body mass index but was similar for the menstrual phases. Breast density was associated with genetic expression of the androgen receptor and remained significant after adjustment for age (rs = 0.56; p = 0.04). After adjustement for age, breast density was also marginally associated with expression of the caspase 3 gene (0.55; 0.053). However, protein levels of caspase 3 was negatively associated (-0.61; 0.03).
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Selective Serotonin Reuptake Inhibitors and Bone Mineral Density in a Population of U. S. Premenopausal WomenPeterson, Lori J 01 January 2011 (has links) (PDF)
Selective Serotonin Reuptake Inhibitors and Bone mineral Density in a Population of U.S. Premenopausal Women
May 2011
M.S., UNIVERSITY of Massachusetts Amherst
Directed by: Professor Elizabeth R. Bertone-Johnson
Low bone mineral density (BMD) in post-menopausal women is a risk factor for bone fractures and osteoporosis development. Prior studies in post-menopausal women have shown the use of antidepressant medications, specifically selective serotonin reuptake inhibitors (SSRIs) to be inversely related to BMD. However, the association has not been studied in pre-menopausal women. Current SSRI use is widespread with 8% of U.S. women age 18-44 reporting use. We evaluated the association between SSRIs and BMD and bone mineral content (BMC) cross-sectionally using data from the University of Massachusetts Vitamin D Status Study. SSRI use, diet, and lifestyle factors were assessed by questionnaire. BMD and BMC were measured using dual-energy x-ray absorptiometry (DEXA). The study included 256 women aged 18-30 (mean=21.6 years, SD=4.3 years). In this population, SSRI use was 5%, BMD values ranged from 0.97-1.38 g/cm2 (mean 1.16, SD 0.08), and BMC values ranged from 1833g to 3682g (mean 2541.5, SD=349.2). After adjustment for age, body mass index, and physical activity, mean BMD in the 13 users of SSRIs was 1.15g/cm2 (SD=0.06) compared to 1.16g/cm2 (SD=0.77) in the 243 non-users (p =0.66). After the same adjustments, mean BMC in the 13 users was 2467.1g (SD=285.0) compared to 2547.6g (SD=352.6) in the 243 non-users (p=0.94). Our findings do not support an inverse association between SSRI use and BMD or BMC. However, given the prevalence of SSRI use in young women and the potential for adverse effects on bone health, further study of this association is warranted.
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Doença óssea em pacientes com nefrite lúpica: aspectos inflamatórios / Bone disease in lupus nephritis patients: inflammatory aspectsResende, Aline Lázara 09 April 2014 (has links)
INTRODUÇÃO: O comprometimento ósseo em pacientes portadoras de nefrite lúpica é comum e multifatorial. O objetivo deste trabalho foi estudar a contribuição do componente inflamatório para o comprometimento ósseo destas pacientes. MÉTODOS: Foram estudadas 15 pacientes do sexo feminino (no menacme) com diagnóstico recente (<= 2 meses) de Lupus Eritematoso Sistêmico e Nefrite Lúpica (NL). Foram excluídos pacientes com história/evidência de doença renal ou óssea prévia. A avaliação laboratorial incluiu a dosagem de 25-hidroxivitamina D3 ([25(OH)D] e de citocinas inflamatórias associadas a fisiopatologia do lupus [Interleucina-6, Fator de necrose tumoral ? e Monocyte Chemoattractant Protein-1 (MCP-1)]. Além disso, as pacientes foram submetidas a biópsia óssea, com análise histomorfométrica, imunohistoquímica e cultura celular (estudo da proliferação e citometria de fluxo). RESULTADOS: As pacientes lúpicas apresentavam em média 29,5±10 anos, com uma proteinúria de 4,7±2,9 g/dia, e uma taxa de filtração glomerular estimada de 37(31-87) ml/min/1,73m², e estavam em uso de glicocorticóide por 34±12 dias. Todas as pacientes apresentavam níveis insuficientes de vitamina D (9,9±4,4ng/ml, variando de 4 a 20 ng/ml). Os níveis de 25(OH)D se correlacionaram negativamente com os de todas as citocinas inflamatórias estudadas. Os níveis de MCP-1 urinário se correlacionaram negativamente com os de 25(OH)D (r= -0,53, p=0,003) e positivamente com os de deoxipiridinolina (r=0,53, p=0,004). Não observamos diferença significativa entre pacientes e controles na proliferação de osteoblastos medida pela incorporação pela timidina (82,22±8,43 vs 56,06±23,73 contagem por minuto, p=0,21). Os osteoblastos provenientes dos fragmentos ósseos das pacientes lúpicas apresentaram uma maior expressão de MCP-1, medida pela intensidade média de fluorescência (32,0±9,1 vs 22,9±5,3, p=0,01). Quando comparadas a controles, as pacientes portadoras de nefrite lúpica apresentaram valores significativamente inferiores de dois parâmetros de formação óssea (volume e espessura osteoide). Além disso, detectamos também uma redução em dois parâmetros de mineralização óssea (superfície mineralizante e taxa de formação óssea). Por fim, as pacientes lúpicas apresentaram um aumento significativo da reabsorção óssea e da superfície osteoclástica. Com relação a imunohistoquímica, as pacientes lúpicas apresentaram uma menor expressão de osteoprotegerina (0,61±0,82 vs 1,08±0,50, p=0,003) e uma maior expressão do receptor ativador do fator nuclear-?B ligante (RANKL) (1,76±0,92 vs 0,41±0,28, p<0,001) quando comparadas aos controles. CONCLUSÕES: Pacientes com diagnóstico recente de nefrite lúpica, submetidas a um reduzido tempo de exposição e carga cumulativa de corticóide, apresentam um significativo comprometimento ósseo, caracterizado por uma redução da formação e mineralização óssea, associada a um aumento da reabsorção óssea. Os níveis de MCP-1 urinário se correlacionaram negativamente com os de 25-hidroxivitamina D3 e positivamente com os de deoxipiridinolina, sugerindo que fatores inflamatórios possam contribuir para a insuficiência de vitamina D e a reabsorção óssea. A expressão óssea aumentada de RANKL e reduzida de OPG, assim como o aumento da expressão de MCP-1 pelas células ósseas das pacientes lúpicas, reiteram a hipótese de que a inflamação per se possa influenciar a reabsorção óssea observada nestas pacientes / INTRODUCTION: Bone disease in lupus nephritis patients is common and multifactorial. The aim of this study was evaluate the contribution of inflammatory factors to the bone disorder observed in these patients. METHODS: We studied 15 female pre-menopausal patients with <= 2 months of diagnosed Systemic Erythematosus Lupus and Lupus Nephritis (LN). Subjects with prior kidney or bone disease were excluded. We measured the levels of 25-hydroxyvitamin D3 [25(OH)D] and cytokines involved in LN physiopathology [Interleucin-6, Tumor Necrosis Factor ?, and Monocyte Chemoattractant Protein-1 (MCP-1)]. Patients were submitted to bone biopsy, followed by osteoblast culture (cell proliferation and flow cytometry), histomorphometric and immunohistochemistry analysis. RESULTS: LN patients presented a mean age of 29.5±10 years, a proteinuria of 4.7±2.9 g/day and an estimated glomerular filtration rate of 37(31-87) ml/min/1,73m². They were on glucocorticoid therapy for 34±12 days. All patients presented vitamin D insufficiency (9.9±4.4 ng/ml, range 4-20). Vitamin D levels were negatively correlated with all inflammatory cytokines. Urinary MCP-1 correlated negatively with 25-hydroxyvitamin D3 (r= -0.53, p=0.003) and positively with serum deoxypyridinoline (r=0.53, p=0.004). There were no differences between NL patients and controls in osteoblast proliferation measured by incorporation of thymidine (82.22±48.43 vs 56.07±23.73 counts per minute, respectively, p=0.21). Osteoblasts isolated from LN patients presented a significantly higher expression of MCP-1, as measured by mean fluorescence intensities (32.0±9.1 vs 22.9±5.3, p=0.01). LN patients presented a significantly reduction in two formation parameters (osteoid volume and osteoid thickness). They also presented a decrease in mineralization surface and bone formation rate, associated with an increased eroded surface and osteoclast surface. Patient\'s bone specimens demonstrated a reduced immunostaining for osteoprotegerin (0.61±0.82 vs 1.08±0.50%, p=0.003), and an increased expression of Receptor Activator of NF-kB ligand (RANKL) (1.76±0.92 vs 0.41±0.28%, p < 0.001) when compared to controls. CONCLUSION: Newly diagnosed lupus nephritis patients, submitted to a limited time of exposure and to a low cumulative dose of glucocorticoids, presented a significant disturbance in bone metabolism, characterized by an impaired bone formation and mineralization, associated with an increase in resorption parameters. The levels of urinary MCP-1 were negatively correlated to 25-hydroxyvitamin D3 and positively correlated to serum deoxypyridinoline, suggesting that inflammation may contribute to vitamin D insufficiency and bone resorption. Bone tissue overexpression of RANKL and underexpression of osteoprotegerin, as well as increased expression of MCP-1 by cultured bone explants cells reinforces inflammatory background contributing to bone resorption in LN bone disease
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Uticaj modela programa vežbanja na koštanu gustinu i biohemijske markere koštanog remodelovanja kod žena u pre- i postmenopauzi / The effects of the model of exercise program onbone mineral density and biochemical markers of bone turnover in pre- and postmenopausal womenMarijanac Ana 24 September 2018 (has links)
<p>Generalni cilj ovog istraživanja je da se utvrdi da li postoji uticaj primenjenog<br />programa vežbanja na parametre koštane gustine i biohemijske markere koštanog<br />remodelovanja kod žena u periodu premenopauze i postmenopauze.<br />Uzorak ispitanica je činilo 26 žena starosti 45 do 55 godina, od kojih su 13 u periodu<br />premenopauze, a 13 u periodu postmenopauze. Ispitanice su učestvovale u programu vežbanja<br />u trajanju od 6 meseci, koji se realizovao u Novom Sadu, 4 puta nedeljno u trajanju od sat<br />vremena. Za utvrđivanje uticaja programa vežbanja na koštanu gustinu merena su 3<br />osteodenzitometrijska parametra na kičmi, vratu butne kosti i kuku i 5 parametara<br />biohemijskih markera koštanog remodelovanja.<br />Da bi se utvrdio uticaj vežbanja kod ispitanica, primenjena je multivarijatna analize<br />varijanse (MANOVA). Na celokupnom uzorku ispitanica nije utvrđena statistički značajna<br />razlika ni u jednom merenom parametru koštane gustine. U odnosu na biohemijske markere,<br />došlo je do značajnog smanjenja nivoa ukupne alkalne fosfataze. Kod žena u periodu<br />premenopauze i kod žena u periodu postmenopauze, program vežbanja nije značajno uticao<br />na parametre koštane gustine merene na kičmi, vratu butne kosti i kuku (DXA, Lunar<br />Prodrigy), kao ni na parametre biohemijskih markera koštanog remodelovanja.<br />Primenom multivarijatne analize kovarijanse (MANCOVA) utvrđena je značajna<br />razlika u uticaju programa vežbanja između žena u pre- i postmenopauzi u mineralnoj<br />koštanoj gustini vrata butne kosti (BMD VF) i markera beta-crosslaps (CTX). Mineralna<br />koštana gustina je nakon programa vežbanja veća, a nivo beta-crosslapsa niži kod žena u<br />premenopauzi nego kod žena u periodu postmenopauze.<br />Na osnovu dobijenih rezultata, zaključujemo da je potreban duži vremenski period<br />realizacije programa vežbanja kako bi se mogla primetiti statistički značajna promena<br />merenih parametara. Ispitanicama se savetuje da nastave sa vežbanjem kako bi usporile<br />gubitak kosti</p> / <p>The genaral aim of this research is to determine is there an effects of the applied exercise<br />program on bone mineral density and and biochemical markers of bone turnover in the<br />premenopausal and postmenopausal period.<br />The sample was consisted of 26 women aged 45 to 55 years, of which 13 were in<br />premenopausal and 13 in postmenopausal period. Subjects were included (had performing) in 6-month<br />exercise program, which was implemented (maintained) in Novi Sad, 4 times a week in duration for an<br />hour. Three osteodensitometric parameters on lumbar spine, femoral neck and hip (DXA, Lunar<br />Prodrigy) and five parameters of biochemical markers of bone turnover were measured to assessed<br />(to determine) the effects of exercise program on bone density.<br />Multivariate analysis of variance (MANOVA) was used to determine the effect of exercise.<br />For the entire sample of subjects, there were no statistically significant difference in any measured<br />bone density parameter, but looking at biochemical markers, total alkaline phosphatase level were<br />significanly reduced. There were no significant changes in bone density parameters on the lumbar<br />spine, femoral neck and hip nor on the parameters of biochemical markers of bone turnover in women<br />in premenopausal and postmenopausal period.<br />Applying multivariate analyse of covariance it was found a significant difference in the<br />exercise program effect between pre- and postmenopausal women in bone mineral density of femoral<br />neck (BMD VF) and beta-crosslaps marker of turnover (CTX). Femoral neck BMD was higher, and<br />beta-crosslaps level was lower in premenopausal women than in postmenopausal women after<br />completion exercise program.<br />Based on obtained results, we conclude that is required a longer perod of exercise program<br />ralization in order to notice a statistically significant change in measured parameters. Subjects are<br />advised to continue their exercising in order to slow down the bone loss</p>
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Doença óssea em pacientes com nefrite lúpica: aspectos inflamatórios / Bone disease in lupus nephritis patients: inflammatory aspectsAline Lázara Resende 09 April 2014 (has links)
INTRODUÇÃO: O comprometimento ósseo em pacientes portadoras de nefrite lúpica é comum e multifatorial. O objetivo deste trabalho foi estudar a contribuição do componente inflamatório para o comprometimento ósseo destas pacientes. MÉTODOS: Foram estudadas 15 pacientes do sexo feminino (no menacme) com diagnóstico recente (<= 2 meses) de Lupus Eritematoso Sistêmico e Nefrite Lúpica (NL). Foram excluídos pacientes com história/evidência de doença renal ou óssea prévia. A avaliação laboratorial incluiu a dosagem de 25-hidroxivitamina D3 ([25(OH)D] e de citocinas inflamatórias associadas a fisiopatologia do lupus [Interleucina-6, Fator de necrose tumoral ? e Monocyte Chemoattractant Protein-1 (MCP-1)]. Além disso, as pacientes foram submetidas a biópsia óssea, com análise histomorfométrica, imunohistoquímica e cultura celular (estudo da proliferação e citometria de fluxo). RESULTADOS: As pacientes lúpicas apresentavam em média 29,5±10 anos, com uma proteinúria de 4,7±2,9 g/dia, e uma taxa de filtração glomerular estimada de 37(31-87) ml/min/1,73m², e estavam em uso de glicocorticóide por 34±12 dias. Todas as pacientes apresentavam níveis insuficientes de vitamina D (9,9±4,4ng/ml, variando de 4 a 20 ng/ml). Os níveis de 25(OH)D se correlacionaram negativamente com os de todas as citocinas inflamatórias estudadas. Os níveis de MCP-1 urinário se correlacionaram negativamente com os de 25(OH)D (r= -0,53, p=0,003) e positivamente com os de deoxipiridinolina (r=0,53, p=0,004). Não observamos diferença significativa entre pacientes e controles na proliferação de osteoblastos medida pela incorporação pela timidina (82,22±8,43 vs 56,06±23,73 contagem por minuto, p=0,21). Os osteoblastos provenientes dos fragmentos ósseos das pacientes lúpicas apresentaram uma maior expressão de MCP-1, medida pela intensidade média de fluorescência (32,0±9,1 vs 22,9±5,3, p=0,01). Quando comparadas a controles, as pacientes portadoras de nefrite lúpica apresentaram valores significativamente inferiores de dois parâmetros de formação óssea (volume e espessura osteoide). Além disso, detectamos também uma redução em dois parâmetros de mineralização óssea (superfície mineralizante e taxa de formação óssea). Por fim, as pacientes lúpicas apresentaram um aumento significativo da reabsorção óssea e da superfície osteoclástica. Com relação a imunohistoquímica, as pacientes lúpicas apresentaram uma menor expressão de osteoprotegerina (0,61±0,82 vs 1,08±0,50, p=0,003) e uma maior expressão do receptor ativador do fator nuclear-?B ligante (RANKL) (1,76±0,92 vs 0,41±0,28, p<0,001) quando comparadas aos controles. CONCLUSÕES: Pacientes com diagnóstico recente de nefrite lúpica, submetidas a um reduzido tempo de exposição e carga cumulativa de corticóide, apresentam um significativo comprometimento ósseo, caracterizado por uma redução da formação e mineralização óssea, associada a um aumento da reabsorção óssea. Os níveis de MCP-1 urinário se correlacionaram negativamente com os de 25-hidroxivitamina D3 e positivamente com os de deoxipiridinolina, sugerindo que fatores inflamatórios possam contribuir para a insuficiência de vitamina D e a reabsorção óssea. A expressão óssea aumentada de RANKL e reduzida de OPG, assim como o aumento da expressão de MCP-1 pelas células ósseas das pacientes lúpicas, reiteram a hipótese de que a inflamação per se possa influenciar a reabsorção óssea observada nestas pacientes / INTRODUCTION: Bone disease in lupus nephritis patients is common and multifactorial. The aim of this study was evaluate the contribution of inflammatory factors to the bone disorder observed in these patients. METHODS: We studied 15 female pre-menopausal patients with <= 2 months of diagnosed Systemic Erythematosus Lupus and Lupus Nephritis (LN). Subjects with prior kidney or bone disease were excluded. We measured the levels of 25-hydroxyvitamin D3 [25(OH)D] and cytokines involved in LN physiopathology [Interleucin-6, Tumor Necrosis Factor ?, and Monocyte Chemoattractant Protein-1 (MCP-1)]. Patients were submitted to bone biopsy, followed by osteoblast culture (cell proliferation and flow cytometry), histomorphometric and immunohistochemistry analysis. RESULTS: LN patients presented a mean age of 29.5±10 years, a proteinuria of 4.7±2.9 g/day and an estimated glomerular filtration rate of 37(31-87) ml/min/1,73m². They were on glucocorticoid therapy for 34±12 days. All patients presented vitamin D insufficiency (9.9±4.4 ng/ml, range 4-20). Vitamin D levels were negatively correlated with all inflammatory cytokines. Urinary MCP-1 correlated negatively with 25-hydroxyvitamin D3 (r= -0.53, p=0.003) and positively with serum deoxypyridinoline (r=0.53, p=0.004). There were no differences between NL patients and controls in osteoblast proliferation measured by incorporation of thymidine (82.22±48.43 vs 56.07±23.73 counts per minute, respectively, p=0.21). Osteoblasts isolated from LN patients presented a significantly higher expression of MCP-1, as measured by mean fluorescence intensities (32.0±9.1 vs 22.9±5.3, p=0.01). LN patients presented a significantly reduction in two formation parameters (osteoid volume and osteoid thickness). They also presented a decrease in mineralization surface and bone formation rate, associated with an increased eroded surface and osteoclast surface. Patient\'s bone specimens demonstrated a reduced immunostaining for osteoprotegerin (0.61±0.82 vs 1.08±0.50%, p=0.003), and an increased expression of Receptor Activator of NF-kB ligand (RANKL) (1.76±0.92 vs 0.41±0.28%, p < 0.001) when compared to controls. CONCLUSION: Newly diagnosed lupus nephritis patients, submitted to a limited time of exposure and to a low cumulative dose of glucocorticoids, presented a significant disturbance in bone metabolism, characterized by an impaired bone formation and mineralization, associated with an increase in resorption parameters. The levels of urinary MCP-1 were negatively correlated to 25-hydroxyvitamin D3 and positively correlated to serum deoxypyridinoline, suggesting that inflammation may contribute to vitamin D insufficiency and bone resorption. Bone tissue overexpression of RANKL and underexpression of osteoprotegerin, as well as increased expression of MCP-1 by cultured bone explants cells reinforces inflammatory background contributing to bone resorption in LN bone disease
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