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1.
J Osteoporos ; 2022: 2522014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36578470

RESUMO

Objectives: Both diabetes mellitus (DM) and osteoporosis are very common in older adults who reside in long-term care (LTC) facilities. Nevertheless, few studies have examined the relationship between diabetes and bone quality in this population. The purpose of this study is to determine if bone mineral density (BMD) or trabecular bone score (TBS) is a better measure of bone quality and skeletal health, in LTC residents with and without a history of DM. Methodology. In this longitudinal cohort study, we examined baseline BMD (lumbar spine, total hip, and femoral neck), TBS, DM, and functional status in 511 LTC residents who were enrolled in two ongoing randomized placebo-controlled osteoporosis clinical trials. Results: On average, participants were older than 80 years and majority were prefrail or frail. Women with DM had greater lumbar spine BMD (1.106 vs 1.017, adjusted difference ± standard error = 0.084 ± 0.023 g/cm2, p = 0.0003) and femoral neck BMD (0.695 vs 0.651, 0.027 ± 0.013 g/cm2, p = 0.0463), but lesser lumbar spine TBS (1.211 vs 1.266, -0.036 ± 0.016, p = 0.0299) compared to women without DM. Total hip BMD was also higher based on descriptive statistics (0.780 vs 0.734, p = 0.6255) in diabetic women, although the difference was not statistically significant. Men had similar but attenuated findings. Conclusions: Among LTC residents, those with DM have greater BMD but lower bone quality measured by TBS. TBS should be considered in assessing older patients with DM. However, further studies are required to confirm the findings with respect to fractures.

2.
Eur J Cardiothorac Surg ; 62(5)2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35460403

RESUMO

OBJECTIVES: We hypothesized that expression and activity of nitric oxide synthase-3 enzyme (Nos3) in bicuspid aortic valve (BAV) aortopathy are related to tissue layer and Nos3 genotype. METHODS: Gene expression of Nos3 and platelet and endothelial cell adhesion molecule-1 (Pecam1) and NOS activity were measured in intima-containing media and adventitial specimens of ascending aortic tissue. The presence of 2 Nos3 single-nucleotide polymorphisms (SNPs; -786T/C and 894G/T) was determined for non-aneurysmal (NA) and aneurysmal patients with BAV (n = 40, 89, respectively); patients with tricuspid aortic valve (TAV) and aneurysm (n = 151); and NA patients with TAV (n = 100). RESULTS: Elevated Nos3 relative to Pecam1 and reduced Pecam1 relative to a housekeeping gene were observed within intima-containing aortic specimens from BAV patients when compared with TAV patients. Lower Nos3 in the adventitia of aneurysmal specimens was noted when compared with specimens of NA aorta, independent of valve morphology. NOS activity was similar among cohorts in media/intima and decreased in the diseased adventitia, relative to control patients. Aneurysmal BAV patients exhibited an under-representation of the wild-type genotype for -786 SNP. No differences in genotype distribution were noted for 894 SNP. Primary intimal endothelial cells from patients with at least 1 C allele at -786 SNP exhibited lower Nos3 when compared with wild-type cells. CONCLUSIONS: These findings of differential Nos3 in media/intima versus adventitia depending on valve morphology or aneurysm reveal new information regarding aneurysmal pathophysiology and support our ongoing assertion that there are distinct mechanisms giving rise to ascending aortopathy in BAV and TAV patients.


Assuntos
Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Humanos , Doenças das Valvas Cardíacas/genética , Doenças das Valvas Cardíacas/metabolismo , Células Endoteliais/metabolismo , Valva Aórtica/metabolismo , Genótipo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-32899196

RESUMO

Sedentary behavior is associated with negative health outcomes and unhealthy aging. Older adults are the most sedentary age group, and decreasing sitting time represents an intervention target for improving health. Determinants of sedentary behavior have been examined in older adults living in their own homes, yet less is known about sedentary behavior of older adults in residential care facilities. The purpose of this study was to explore factors contributing to sedentary behavior among residents of independent and assisted living facilities. We conducted eight focus groups with residents (n = 44) and semi-structured interviews with staff (n = 6) across four living facilities. Audio recordings were transcribed and analyzed using an iterative, inductive approach. Three salient themes were identified. Residents and staff both viewed sedentary behavior negatively unless it was in the context of social engagement. Additionally, fear of falling was discussed as a significant contributor to sedentary behavior. Finally, residents felt the community living environment contributed to their sedentary behavior while staff did not. Our findings provide valuable insight for designing targeted interventions for older adults in residential facilities and suggest thinking beyond the individual and considering environmental influences on sedentary behavior in the residential care setting.


Assuntos
Moradias Assistidas , Comportamento Sedentário , Acidentes por Quedas , Idoso , Idoso de 80 Anos ou mais , Medo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Instituições Residenciais
4.
Arch Osteoporos ; 15(1): 79, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32458096

RESUMO

Clinicians and patients want to know if therapy is working early in their course of treatment. We found that early changes in bone turnover markers at 6 months were associated with long-term changes in bone mineral density but not trabecular bone score at 12 and 24 months. PURPOSE: We sought to examine the association between shorter-term changes in markers of bone turnover and longer-term changes in bone mineral density (BMD) and microstructure in a cohort of frail elderly women with multiple comorbid conditions including osteoporosis. METHODS: We performed a secondary analysis of a 2-year zoledronic acid trial for osteoporosis in 155 women residents of long-term care communities (mean age 86.9 years). We examined the association of the 6-month change in serum C-terminal crosslinking telopeptide of type I collagen (CTX) and serum intact procollagen type I N propeptide (PINP) with the 12- and 24-month changes in BMD at the spine and hip and the trabecular bone score (TBS), an indirect measure of bone microstructure. RESULTS: For every 0.2-ng/ml 6-month CTX decrease, the corresponding increase in spine BMD at 12 and 24 months was 0.2% (p = 0.7210) and 1.1% (p = 0.0396), respectively; total hip BMD 1.1% (p = 0.0279) and 0.9% (p = 0.0716); and femoral neck BMD 1.7% (p = 0.0079) and 0.9% (p = 0.1698). Similarly, for every 20-ng/ml 6-month PINP decrease, the corresponding increase in spine BMD at 12 and 24 months was 0.9% (p = 0.0286) and 1.4% (p = 0.0012), respectively; total hip BMD 1.4% (p = 0.0005) and 1.4% (p = 0.0006); and femoral neck BMD 2.3% (p < 0.0001) and 2.0% (p < 0.0001). Bone marker changes were not consistently associated with TBS changes. CONCLUSION: Shorter-term 6-month changes in bone turnover markers are associated with the long-term changes in BMD over 1-2 years in the spine and hip but not with TBS.


Assuntos
Osteoporose , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Densidade Óssea , Remodelação Óssea , Osso Esponjoso/diagnóstico por imagem , Feminino , Idoso Fragilizado , Humanos , Osteoporose/diagnóstico por imagem
6.
Front Oncol ; 9: 525, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31355130

RESUMO

Melatonin has numerous anti-cancer properties reported to influence cancer initiation, promotion, and metastasis. With the need for effective hormone therapies (HT) to treat menopausal symptoms without increasing breast cancer risk, co-administration of nocturnal melatonin with a natural, low-dose HT was evaluated in mice that develop primary and metastatic mammary cancer. Individually, melatonin (MEL) and estradiol-progesterone therapy (EPT) did not significantly affect mammary cancer development through age 14 months, but, when combined, the melatonin-estradiol-progesterone therapy (MEPT) significantly repressed tumor formation. This repression was due to effects on tumor incidence, but not latency. These results demonstrate that melatonin and the HT cooperate to decrease the mammary cancer risk. Melatonin and EPT also cooperate to alter the balance of the progesterone receptor (PR) isoforms by significantly increasing PRA protein expression only in MEPT mammary glands. Melatonin significantly suppressed amphiregulin transcripts in MEL and MEPT mammary glands, suggesting that amphiregulin together with the higher PRA:PRB balance and other factors may contribute to reducing cancer development in MEPT mice. Melatonin supplementation influenced mammary morphology by increasing tertiary branching in the mouse mammary glands and differentiation in human mammary epithelial cell cultures. Uterine weight in the luteal phase was elevated after long-term exposure to EPT, but not to MEPT, indicating that melatonin supplementation may reduce estrogen-induced uterine stimulation. Melatonin supplementation significantly decreased the incidence of grossly-detected lung metastases in MEL mice, suggesting that melatonin delays the formation of metastatic lesions and/or decreases aggressiveness in this model of HER2+ breast cancer. Mammary tumor development was similar in EPT and MEPT mice until age 8.6 months, but after 8.6 months, only MEPT continued to suppress cancer development. These data suggest that melatonin supplementation has a negligible effect in young MEPT mice, but is required in older mice to inhibit tumor formation. Since melatonin binding was significantly decreased in older mammary glands, irrespective of treatment, melatonin supplementation may overcome reduced melatonin responsiveness in the aged MEPT mice. Since melatonin levels are known to decline near menopause, nocturnal melatonin supplementation may also be needed in aging women to cooperate with HT to decrease breast cancer risk.

7.
J Aging Phys Act ; 27(2): 222-229, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30117355

RESUMO

The aim of this study was to evaluate accuracy of seven commercial activity monitors in measuring steps in older adults with varying walking abilities and to assess monitor acceptability and usability. Forty-three participants (age = 87 ± 5.7 years) completed a gait speed assessment, two walking trials while wearing the activity monitors, and questionnaires about usability features and activity monitor preferences. The Accusplit AX2710 Accelerometer Pedometer had the highest accuracy (93.68% ± 13.95%), whereas the Fitbit Charge had the lowest (39.12% ± 40.3%). Device accuracy varied based on assistive device use, and none of the monitors were accurate at gait speeds <0.08 m/s. Barriers to monitor usability included inability to apply monitor and access the step display. Monitor accuracy was rated as the most important feature, and ability to interface with a smart device was the least important feature. This study identified the limitations of the current commercial activity monitors in both step counting accuracy and usability features for older adults.


Assuntos
Actigrafia/instrumentação , Exercício Físico , Velocidade de Caminhada , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
8.
Gerontol Geriatr Med ; 4: 2333721418781126, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29977979

RESUMO

Objective: The aim of this study is to evaluate accuracy of research activity monitors in measuring steps in older adults with a range of walking abilities. Method: Participants completed an initial assessment of gait speed. The accuracy of each monitor to record 100 steps was assessed across two walking trials. Results: In all, 43 older adults (age 87 ± 5.7 years, 81.4% female) participated. Overall, the StepWatch had the highest accuracy (99.0% ± 1.5%), followed by the ActivPAL (93.7% ± 11.1%) and the Actigraph (51.4% ± 35.7%). The accuracy of the Actigraph and ActivPAL varied according to assistive device use, and the accuracy of all three monitors differed by gait speed category (all p < .05). StepWatch was highly accurate (⩾97.7) across all conditions. Discussion: The StepWatch and ActivPAL monitor were reasonably accurate in measuring steps in older adults who walk slowly and use an assistive device. The Actigraph significantly undercounted steps in those who walk slow or use an assistive device. Researchers should consider gait speed and the use of assistive devices when selecting an activity monitor.

9.
J Am Geriatr Soc ; 66(2): 316-320, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29155456

RESUMO

OBJECTIVES: To establish the prevalence of sarcopenia in a long-term care population, assess agreement among different consensus sarcopenia diagnostic criteria, and examine agreement of a self-reported questionnaire with consensus guidelines. DESIGN: Cross-sectional secondary analysis. SETTING: Long-term care communities in the greater Pittsburgh, Pennsylvania, area. PARTICIPANTS: Women aged 65 and older (mean 83.6) undergoing eligibility screening for a fracture reduction trial (N = 141). MEASUREMENTS: We measured appendicular lean muscle mass using dual-energy X-ray absorptiometry. Hand grip strength and usual gait speed were also evaluated. Sarcopenia status was determined according to European Working Group on Sarcopenia in Older People (EWGSOP) and the Foundation for the National Institutes of Health (FNIH) Sarcopenia Project criteria and the SARC-F questionnaire. RESULTS: Eleven participants were sarcopenic (7.8%) according to the EWGSOP criteria, six (4.3%) according to FNIH conservative cut-point guidelines, and 32.6% (n = 46) according to FNIH intermediate cut-points. Only 2 of 141 participants met criteria for sarcopenia according to all three guidelines. Sarcopenia was identified in 30 (21.3%) participants according to the SARC-F questionnaire. Sensitivity of the SARC-F with consensus panel definitions ranged from 18.2% to 33.3%. Specificity ranged from 78.7% to 81.1%. CONCLUSION: Current consensus criteria from the EWGSOP and FNIH Sarcopenia Project do not agree and have little overlap in older female long-term care residents. The SARC-F questionnaire is a simple tool that could be implemented in long-term care, but it has low sensitivity compared with current consensus guidelines in the identification of sarcopenic individuals.


Assuntos
Guias como Assunto/normas , Assistência de Longa Duração , Programas de Rastreamento , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Absorciometria de Fóton/métodos , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Força da Mão/fisiologia , Humanos , Pennsylvania/epidemiologia , Prevalência , Autorrelato , Inquéritos e Questionários , Velocidade de Caminhada/fisiologia
10.
J Pineal Res ; 64(3)2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29285799

RESUMO

The Melatonin Osteoporosis Prevention Study (MOPS) demonstrated that nightly melatonin resulted in a time-dependent decrease in equilibrium ratios of serum osteoclasts and osteoblasts in perimenopausal women. This study examines mechanisms related to the ratios of osteoblasts and osteoclasts using coculture models (transwell or layered) of human mesenchymal stem cell (MSC) and human peripheral blood monocytes (PBMCs). Human MSC/PBMC cocultures exposed to melatonin in osteogenic (OS+) medium for 21 days induced osteoblast differentiation and mineralization; however, only in layered cocultures did melatonin inhibit osteoclastogenesis. Melatonin effects were mediated through MT2 melatonin receptors, MEK1/2, and MEK5. In layered but not transwell cocultures, melatonin increased OPG:RANKL ratios by inhibiting RANKL, suggesting that contact with osteoclasts during osteoblastogenesis inhibits RANKL secretion. Melatonin modulated expression of ERK1/2, ERK5, ß1 integrin, GLUT4, and IRß that was dependent upon the type of coculture; however, in both cultures, melatonin increased RUNX2 and decreased PPARγ expression, indicating a role for metabolic processes that control osteogenic vs adipogenic cell fates of MSCs. Furthermore, melatonin also has osteoblast-inducing effects on human adipose-derived MSCs. In vivo, one-year nightly melatonin (15 mg/L) given to neu female mice in their drinking water increased pErk1/2, pErk5, Runx2, and Opg and Rankl levels in bone consistent with melatonin's already reported bone-enhancing effects. Finally, analysis of daily logs from the MOPS demonstrated a significant improvement in mood and perhaps sleep quality in women receiving melatonin vs placebo. The osteoblast-inducing, bone-enhancing effects of melatonin and improvement in quality of life suggest that melatonin is a safe and effective bone loss therapy.


Assuntos
Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Melatonina/farmacologia , Osteogênese/efeitos dos fármacos , Perimenopausa/efeitos dos fármacos , Animais , Células Cultivadas , Técnicas de Cocultura , Humanos , MAP Quinase Quinase Quinases/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Qualidade de Vida , Receptor MT2 de Melatonina/metabolismo
11.
J Thorac Cardiovasc Surg ; 154(5): 1756-1762, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28651938

RESUMO

OBJECTIVE: Congenital bicuspid aortic valve (BAV) is distinctly associated with the development of ascending aortopathy in adulthood, portending risk of both ascending aortic aneurysm and dissection. Our previous work implicated deficiency in oxidative stress response as a mediator of the BAV-associated aortopathy. We hypothesize that reactive oxygen species generation invokes elevated local oxidative tissue damage in ascending aorta of patients with BAV. METHODS: Ascending aortic specimens were obtained from patients undergoing elective aortic replacement and/or aortic valve replacement and during heart transplant operations. Levels of superoxide anion were measured via high-pressure liquid chromatography-based detection of 2-hydroxyethidium in aortic specimens. Lipid peroxidation and enzymatic activity of superoxide dismutase and peroxidase were quantified in aortic specimens. RESULTS: Superoxide anion production was elevated in aortic specimens from patients with nonaneurysmal BAV (n = 59) compared with specimens from patients with the morphologically normal tricuspid aortic valve (TAV, n = 38). Total superoxide dismutase activity was similar among aortic specimens from patients with TAV versus BAV (n = 27 and 26, respectively), whereas peroxidase activity was increased in aortic specimens from patients with BAV compared with specimens from patients with TAV (n = 14 for both groups). Lipid peroxidation was elevated in aortic specimens from BAV patients compared with TAV patients (n = 14 and 11, respectively). CONCLUSIONS: Superoxide anion accumulation and increased lipid peroxidation demonstrate that, despite increased peroxidase activity, the ascending aortopathy of patients with BAV involves oxidative stress. In addition, the absence of increased superoxide dismutase activity in BAV specimens indicates a deficiency in antioxidant defense. This suggests that the characteristic smooth muscle cell loss observed in BAV aortopathy may be a consequence of superoxide-mediated cell damage.


Assuntos
Aorta , Aneurisma Aórtico , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/complicações , Estresse Oxidativo , Túnica Média , Idoso , Aorta/metabolismo , Aorta/patologia , Aneurisma Aórtico/etiologia , Aneurisma Aórtico/metabolismo , Aneurisma Aórtico/patologia , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Doença da Válvula Aórtica Bicúspide , Cromatografia Líquida/métodos , Etídio/análogos & derivados , Etídio/análise , Feminino , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/análise , Superóxidos/análise , Túnica Média/metabolismo , Túnica Média/patologia
12.
Ann Thorac Surg ; 104(1): 79-87, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28185644

RESUMO

BACKGROUND: Bicuspid aortic valve (BAV) is associated with asymmetric dilatation of the proximal ascending aorta. We previously demonstrated increased susceptibility of smooth muscle cells to oxidative stress in the BAV-aneurysmal aorta and hypothesized that antioxidant expression is regionally defined and influenced by the BAV morphotype. METHODS: BAV valve morphology was defined according to number of raphes: type 0 (0 raphes), type 1 (1 raphe), or type 2 (2 raphes) and by the raphe location among the left (L), right (R) or non (N) coronary cusps. Ascending aortic specimens were partitioned into three regions corresponding to the sinuses of Valsalva, denoted R, N (greater curve), and L (lesser curve). Transcripts 1, 2, and 3 from the gene expressing superoxide dismutase (Sod) were quantified in all three regions. Results were compared with aneurysmal and nonaneurysmal aortic specimens from patients with a tricuspid aortic valve. RESULTS: Region-specific Sod1 upregulation and Sod2 downregulation were dependent on the BAV morphotype. Sod3 was uniformly downregulated in all regions in a morphotype-independent manner. Sod1 upregulation was noted in the R region of the nonaneurysmal type 1 L/R morphotype. Aortic valve regurgitation, but not stenosis, affected the expression of Sod isoforms in specimens of degenerative aneurysms. CONCLUSIONS: Region-specific transcription profiles of Sod on the basis of BAV morphotype deepen our understanding of its associated aortopathy and provide biological insight on the asymmetric dilatation pattern. This work indicates regional differences exist in the oxidative stress biology of the proximal aortic wall, and this may lead to newer diagnostic techniques to adjudicate aortic catastrophe risk.


Assuntos
Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/genética , Valva Aórtica/anormalidades , Regulação da Expressão Gênica , Doenças das Valvas Cardíacas/etiologia , RNA/genética , Superóxido Dismutase-1/genética , Idoso , Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/metabolismo , Doença da Válvula Aórtica Bicúspide , Angiografia por Tomografia Computadorizada , Ecocardiografia , Feminino , Doenças das Valvas Cardíacas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Superóxido Dismutase-1/biossíntese
13.
Am J Geriatr Psychiatry ; 24(12): 1221-1227, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27743842

RESUMO

OBJECTIVE: To determine the risk of recurrent falls associated with antidepressants other than tricyclics (TCAs) and selective serotonin reuptake inhibitors (SSRIs) among frail older women. METHODS: This is a secondary analysis of the Zoledronic acid in frail Elders to STrengthen bone, or ZEST, trial data treated as a longitudinal cohort in 181 frail, osteoporotic women aged ≥65 years in long-term care. The primary exposure was individual non-TCA/non-SSRI antidepressants (i.e., serotonin norepinephrine reuptake inhibitors, mirtazapine, trazodone, and bupropion) at baseline and 6 months. The main outcome was recurrent (at least two) falls within 6 months after antidepressant exposure. Adjusted odds ratios (AORs) and 95% confidence intervals (CIs) were derived using a generalized estimating equations model. RESULTS: At least 15% of women experienced recurrent falls between 0-6 and 6-12 months. At baseline and 6 months, 18.2% and 6.9% had a non-TCA/non-SSRI antidepressant, respectively. Adjusting for demographics, health status, and other drugs that increase risk of falls, non-TCA/non-SSRI antidepressant exposure significantly increased the risk of recurrent falls (AOR: 2.14; 95% CI: 1.01-4.54). Fall risk further increased after removing bupropion from the non-TCA/non-SSRI antidepressant group in sensitivity analyses (AOR: 2.73; 95% CI: 1.24-6.01). CONCLUSIONS: Other antidepressant classes may not be safer than TCAs/SSRIs with respect to recurrent falls in frail older women.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Antidepressivos/efeitos adversos , Idoso Fragilizado/estatística & dados numéricos , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Trazodona/efeitos adversos , Idoso de 80 Anos ou mais , Bupropiona/efeitos adversos , Feminino , Humanos , Mianserina/efeitos adversos , Mianserina/análogos & derivados , Mirtazapina , Recidiva , Fatores de Risco
14.
Ann Thorac Surg ; 102(4): 1274-81, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27283108

RESUMO

BACKGROUND: Endothelial nitric oxide (NO) synthase (eNOS) has been implicated in the development of bicuspid aortic valve (BAV) and with differential expression in the ascending aorta of BAV patients. However, little is known about functional disruptions in the eNOS pathway and the effect on BAV-associated aortic dilatation. We tested the hypothesis that eNOS function is regionally diminished in ascending thoracic aortic aneurysms associated with BAV. METHODS: Thoracic aortic aneurysms specimens were collected from patients with BAV (n = 21) or tricuspid aortic valve (n = 12). Tissue samples were harvested from three circumferential regions corresponding to locations above the right, left, and noncoronary sinuses. Adventitial-stripped specimens containing media and intima only were analyzed for NO synthase 3 gene expression and total eNOS protein. Indicators of eNOS activity (pSer1177-eNOS) and NO bioavailability (phosphorylation of vasodilator-stimulated phosphoprotein at Ser239) were also measured. RESULTS: NO synthase 3 and eNOS protein were elevated in the right aortic region of BAV specimens compared with tricuspid aortic valve specimens. Activation of eNOS, as indicated by pSer1177-eNOS, was higher in BAV specimens across all regions. Despite increases in eNOS and pSer1177-eNOS, BAV specimens displayed no change in pSer239-vasodilator-stimulated phosphoprotein compared with tricuspid aortic valve specimens. CONCLUSIONS: BAV is associated with regional disruptions in the eNOS pathway, most markedly in the right aortic region. The discrepancy between increased eNOS activity and the absence of increased NO bioavailability in this region provides insight into physiologic mechanisms potentially underlying the asymmetric dilatation pattern observed in BAV.


Assuntos
Aneurisma da Aorta Torácica/genética , Valva Aórtica/anormalidades , Regulação da Expressão Gênica , Doenças das Valvas Cardíacas/genética , Óxido Nítrico Sintase Tipo III/genética , Transdução de Sinais/genética , Idoso , Aneurisma da Aorta Torácica/cirurgia , Valva Aórtica/patologia , Doença da Válvula Aórtica Bicúspide , Moléculas de Adesão Celular/genética , Regulação para Baixo , Feminino , Doenças das Valvas Cardíacas/patologia , Humanos , Masculino , Proteínas dos Microfilamentos/genética , Pessoa de Meia-Idade , Fosfoproteínas/genética , Estudos Prospectivos , Estudos de Amostragem , Sensibilidade e Especificidade , Coleta de Tecidos e Órgãos , Valva Tricúspide/fisiologia
15.
J Thorac Cardiovasc Surg ; 147(3): 1056-64, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23764410

RESUMO

OBJECTIVES: Patients with bicuspid aortic valves (BAV) are predisposed to developing ascending thoracic aortic aneurysms (TAA) at an earlier age than patients who develop degenerative TAAs and have a tricuspid aortic valve (TAV). The hypothesis tested is that BAV-associated aortopathy is mediated by a mechanism of matrix remodeling that is distinct from that seen in TAAs of patients with tricuspid aortic valves. METHODS: Aortic specimens were collected during ascending aortic replacement, aortic valve replacement, and heart transplants from nonaneurysmal (NA) donors and recipients. Matrix architecture of the aortic media was assessed qualitatively using multiphoton microscopy followed by quantification of collagen and elastin fiber orientation. α-Elastin was determined and matrix maturity was assessed by quantifying immature and mature collagen and lysyl oxidase (Lox) expression and activity in aortic specimens. Matrix metalloproteinase-2/9 activity was quantified in aortic smooth muscle cells. RESULTS: Elastin and collagen fibers were more highly aligned in BAV-NA and BAV-TAA cases than in TAV-TAA cases, whereas TAV-TAA cases were more disorganized than TAV-NA cases. α-Elastin content was unchanged. Immature collagen was reduced in BAV-NA and BAV-TAA cases when compared with TAV-NA and TAV-TAA cases. Mature collagen was elevated in TAV-TAA cases compared with TAV-NA and BAV-TAA cases. There was a trend toward elevated Lox gene expression and activity and matrix metalloproteinase-2/9 activity for TAV-TAA, BAV-NA, and BAV-TAA specimens. CONCLUSIONS: The highly aligned matrix architecture in patients with BAVs indicates that wall remodeling is distinct from TAV-TAA. Altered matrix architecture and reduced collagen maturity suggest that the effector molecules mediating the remodeling of TAAs are different in BAV and TAV cases.


Assuntos
Aorta Torácica/patologia , Doenças da Aorta/etiologia , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/complicações , Túnica Média/patologia , Adulto , Idoso , Aorta Torácica/química , Doenças da Aorta/metabolismo , Doenças da Aorta/patologia , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Doença da Válvula Aórtica Bicúspide , Biomarcadores/análise , Colágeno/análise , Elastina/análise , Feminino , Doenças das Valvas Cardíacas/metabolismo , Doenças das Valvas Cardíacas/patologia , Humanos , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Pessoa de Meia-Idade , Proteína-Lisina 6-Oxidase/análise , Proteína-Lisina 6-Oxidase/genética , Túnica Média/química
16.
Artigo em Inglês | MEDLINE | ID: mdl-22619689

RESUMO

Morinda citrifolia (noni) is reported to have many beneficial properties, including on immune, inflammatory, quality of life, and cancer endpoints, but little is known about its ability to prevent or treat breast cancer. To test its anticancer potential, the effects of Tahitian Noni Juice (TNJ) on mammary carcinogenesis were examined in MMTV-neu transgenic mice. Mammary tumor latency, incidence, multiplicity, and metastatic incidence were unaffected by TNJ treatment, which suggests that it would not increase or decrease breast cancer risk in women taking TNJ for its other benefits. However, noni may be useful to enhance treatment responses in women with existing HER2/neu breast cancer since TNJ resulted in significant reductions in tumor weight and volume and in longer tumor doubling times in mice. Remarkably, its ability to inhibit the growth of this aggressive form of cancer occurred with the mouse equivalent of a recommended dose for humans (<3 oz/day). A 30-day treatment with TNJ also induced significant changes in mammary secondary ductule branching and lobuloalveolar development, serum progesterone levels, and estrous cycling. Additional studies investigating TNJ-induced tumor growth suppression and modified reproductive responses are needed to characterize its potential as a CAM therapy for women with and without HER2(+) breast cancer.

17.
J Pineal Res ; 53(4): 374-84, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22639972

RESUMO

In this study, the effects of the light/dark cycle, hormone replacement therapy (HRT), and nocturnal melatonin supplementation on osteogenic markers and serum melatonin levels were examined in a blind mouse model (MMTV-Neu transgenic mice). Melatonin levels in this mouse strain (FVB/N) with retinal degeneration (rd-/-) fluctuate in a diurnal manner, suggesting that these mice, although blind, still perceive light. Real-time RT-PCR analyses demonstrated that Runx2, Bmp2, Bmp6, Bglap, and Per2 mRNA levels coincide with melatonin levels. The effect of chronic HRT (0.5 mg 17ß-estradiol + 50 mg progesterone in 1800 kcal of diet) alone and in combination with melatonin (15 mg/L drinking water) on bone quality and density was also assessed by histomorphometry and microcomputed tomography, respectively. Bone density was significantly increased (P < 0.05) after 1 yr of treatment with the individual therapies, HRT (22% increase) and nocturnal melatonin (20% increase) compared to control. Hormone replacement therapy alone also increased surface bone, decreased trabecular space, and decreased the number of osteoclasts without affecting osteoblast numbers compared to the control group (P < 0.05). Chronic HRT + melatonin therapy did not significantly increase bone density, even though this combination significantly increased Bglap mRNA levels. These data suggest that the endogenous melatonin rhythm modulates markers important to bone physiology. Hormone replacement therapy with or without nocturnal melatonin in cycling mice produces unique effects on bone markers and bone density. The effects of these therapies alone and combined may improve bone health in women in perimenopause and with low nocturnal melatonin levels from too little sleep, too much light, or age.


Assuntos
Conservadores da Densidade Óssea/administração & dosagem , Osso e Ossos/efeitos dos fármacos , Ritmo Circadiano/efeitos dos fármacos , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Melatonina/administração & dosagem , Fotoperíodo , Progesterona/administração & dosagem , Animais , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/efeitos da radiação , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 2/metabolismo , Proteína Morfogenética Óssea 6/genética , Proteína Morfogenética Óssea 6/metabolismo , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Osso e Ossos/efeitos da radiação , Ritmo Circadiano/genética , Ritmo Circadiano/efeitos da radiação , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Esquema de Medicação , Quimioterapia Combinada , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Vírus do Tumor Mamário do Camundongo/genética , Melatonina/sangue , Camundongos , Camundongos Transgênicos , Osteocalcina/genética , Osteocalcina/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , RNA Mensageiro/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fatores de Tempo , Microtomografia por Raio-X
18.
J Pineal Res ; 52(4): 414-26, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22220591

RESUMO

The purpose of this double-blind study was to assess the effects of nightly melatonin supplementation on bone health and quality of life in perimenopausal women. A total of 18 women (ages 45-54) were randomized to receive melatonin (3mg, p.o., n=13) or placebo (n=5) nightly for 6months. Bone density was measured by calcaneal ultrasound. Bone turnover marker (osteocalcin, OC for bone formation and NTX for bone resorption) levels were measured bimonthly in serum. Participants completed Menopause-Specific Quality of Life-Intervention (MENQOL) and Pittsburgh Sleep Quality Index (PSQI) questionnaires before and after treatment. Subjects also kept daily diaries recording menstrual cycling, well-being, and sleep patterns. The results from this study showed no significant change (6-month-baseline) in bone density, NTX, or OC between groups; however, the ratio of NTX:OC trended downward over time toward a ratio of 1:1 in the melatonin group. Melatonin had no effect on vasomotor, psychosocial, or sexual MENQOL domain scores; however, it did improve physical domain scores compared to placebo (mean change melatonin: -0.6 versus placebo: 0.1, P<0.05). Menstrual cycling was reduced in women taking melatonin (mean cycles melatonin: 4.3 versus placebo: 6.5, P<0.05), and days between cycles were longer (mean days melatonin: 51.2 versus placebo: 24.1, P<0.05). No differences in duration of menses occurred between groups. The overall PSQI score and average number of hours slept were similar between groups. These findings show that melatonin supplementation was well tolerated, improved physical symptoms associated with perimenopause, and may restore imbalances in bone remodeling to prevent bone loss. Further investigation is warranted.


Assuntos
Densidade Óssea/efeitos dos fármacos , Melatonina/administração & dosagem , Osteoporose/prevenção & controle , Perimenopausa/efeitos dos fármacos , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Colágeno Tipo I/sangue , Método Duplo-Cego , Feminino , Humanos , Melatonina/sangue , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteoporose/sangue , Peptídeos/sangue , Placebos , Qualidade de Vida , Sono/efeitos dos fármacos
19.
J Pineal Res ; 49(3): 222-38, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20626586

RESUMO

The purpose of this study was to determine the critical time periods of melatonin treatment required to induce human mesenchymal stem cells (hAMSCs) into osteoblasts and to determine which osteogenic genes are involved in the process. The study design consisted of adding melatonin for different times (2, 5, 10, 14 or 21 days) toward the end of a 21-day treatment containing osteogenic (OS+) medium or at the beginning of the 21-day treatment and then withdrawn. The results show that a 21-day continuous melatonin treatment was required to induce both alkaline phosphatase (ALP) activity and calcium deposition and these effects were mediated through MT2Rs. Functional analysis revealed that peak ALP levels induced by melatonin were accompanied by attenuation of melatonin-mediated inhibition of forskolin-induced cAMP accumulation. Immunoprecipitation and western blot analyses, respectively, showed that MT2R/ß-arrestin scaffolds complexed to Gi, MEK1/2 and ERK1/2 formed in these differentiated hAMSCs (i.e., when ALP levels were highest) where ERK1/2 resided primarily in the cytosol. It is hypothesized that these complexes form to modulate the subcellular localization of ERK1/2 to affect osteogenic gene expression. Using real-time RT-PCR, chronic melatonin exposure induced the expression of osteogenic genes RUNX-2, osteocalcin and BMP-2, through MT2Rs. No melatonin-mediated changes in the mRNA expression of ALP, BMP-6 or in the oxidative enzymes MtTFA, PGC-1α, Polγ, NRF-1, PDH, PDK and LDH occurred. These data show that a continuous 21-day melatonin exposure is required to induce osteoblast differentiation from hAMSCs through the formation of MT2R/Gi/ß-arrestin/MEK/ERK1/2 complexes to induce osteogenesis.


Assuntos
Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Melatonina/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Arrestinas/genética , Arrestinas/metabolismo , Proteína Morfogenética Óssea 6/genética , Proteína Morfogenética Óssea 6/metabolismo , Humanos , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/genética , MAP Quinase Quinase 2/metabolismo , Osteogênese/genética , Receptor MT2 de Melatonina/genética , Receptor MT2 de Melatonina/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , beta-Arrestinas
20.
Cancer Res ; 68(20): 8377-83, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18922910

RESUMO

Black cohosh is an herbal extract that is often used as an alternative to estrogen-based replacement therapies to treat hot flushes that frequently accompany the transition to menopause. Although cancer-free women as well as breast cancer patients and survivors use black cohosh to relieve vasomotor symptoms, there is limited information on its potential to influence breast cancer development or progression. Therefore, in this study, the effects of black cohosh on mammary tumorigenesis were investigated in the MMTV-neu mouse model due to its similarities to HER2(+) breast cancer, including stochastic development of mammary tumors, which frequently progress to metastatic disease. Using an adjusted dose for the mice to correlate to the recommended dose in women (40 mg/d), no differences were detected in the incidence or onset of mammary tumors in black cohosh-treated versus control females. The lack of effect on mammary tumor development suggests that black cohosh would not influence breast cancer risk if given to women before tumor formation. In contrast, black cohosh significantly increased the incidence of lung metastases in tumor-bearing animals compared with mice fed the isoflavone-free control diet. Additional studies will be needed to correlate these findings to women taking different black cohosh products at various times during breast cancer development; however, these results suggest caution for women using black cohosh, especially for extended periods of time. As metastatic progression is linked to patient survival, these data stress the importance of investigating how women's therapies influence all stages of mammary tumorigenesis, particularly for assessing their safety.


Assuntos
Cimicifuga/toxicidade , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/secundário , Neoplasias Mamárias Experimentais/patologia , Receptor ErbB-2/fisiologia , Animais , Estradiol/sangue , Feminino , Vírus do Tumor Mamário do Camundongo , Camundongos , Camundongos Transgênicos , Receptor ErbB-2/análise , Fatores de Tempo
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