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1.
Adv Biol Regul ; 94: 101043, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39305736

RESUMO

Epigenetic modulation of the immune response entails modifiable and inheritable modifications that do not modify the DNA sequence. While there have been many studies on epigenetic changes in tumor cells, there is now a growing focus on epigenetically mediated changes in immune cells of both the innate and adaptive systems. These changes have significant implications for both the body's response to tumors and the development of potential therapeutic vaccines. This study primarily discusses the key epigenetic alterations, with a specific emphasis on pseudouridination, as well as non-coding RNAs and their transportation, which can lead to the development of cancer and the acquisition of new phenotypic traits by immune cells. Furthermore, the advancement of therapeutic vaccinations targeting the tumor will be outlined.

2.
Eur J Med Chem ; 277: 116757, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39142149

RESUMO

N-heterocyclic carbenes (NHCs) represent suitable ligands for rapid and efficient drug design, because they offer the advantage of being easily chemically modified and can bind several substituents, including transition metals as, for instance, gold derivatives. Gold-NHC complexes possess various biological activities and were demonstrated good candidates as anticancer drugs. Besides, carbazole derivatives are characterized by various pharmacological properties, such as anticancer, antibacterial, anti-inflammatory, and anti-psychotropic. Amongst the latter, N-thioalkyl carbazoles were proved to inhibit cancer cells damaging the nuclear DNA, through the inhibition of human topoisomerases. Herein, we report the design, synthesis and biological evaluation of nine new hybrid molecules in which NHC-Au(I) complexes and N-alkylthiolated carbazoles are linked together, in order to obtain novel biological multitarget agents. We demonstrated that the lead hybrid complexes possess anticancer, anti-inflammatory and antioxidant properties, with a high potential as useful tools for treating distinct aspects of several diseases, amongst them cancer.


Assuntos
Antineoplásicos , Carbazóis , Desenho de Fármacos , Compostos Heterocíclicos , Metano , Carbazóis/química , Carbazóis/farmacologia , Carbazóis/síntese química , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/síntese química , Relação Estrutura-Atividade , Metano/análogos & derivados , Metano/química , Metano/farmacologia , Estrutura Molecular , Ouro/química , Ouro/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/síntese química , Animais , Relação Dose-Resposta a Droga , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Camundongos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/síntese química
3.
Neuroimage Clin ; 28: 102401, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32932053

RESUMO

BACKGROUND AND AIM: The basal ganglia are critical for planned locomotion, but their role in age-related gait slowing is not well known. Spontaneous regional co-activation of brain activity at rest, known as resting state connectivity, is emerging as a biomarker of functional neural specialization of varying human processes, including gait. We hypothesized that greater connectivity amongst regions of the basal ganglia would be associated with faster gait speed in the elderly. We further investigated whether this association was similar in strength to that of other risk factors for gait slowing, specifically white matter hyperintensities (WMH). METHODS: A cohort of 269 adults (79-90 years, 146 females, 164 White) were assessed for gait speed (m/sec) via stopwatch; brain activation during resting state functional magnetic resonance imaging, WMH, and gray matter volume (GMV) normalized by intracranial volume via 3T neuroimaging; and risk factors of poorer locomotion via clinical exams (body mass index (BMI), muscle strength, vision, musculoskeletal pain, cardiometabolic conditions, depressive symptoms, and cognitive function). To understand whether basal ganglia connectivity shows distinct clusters of connectivity, we conducted a k-means clustering analysis of regional co-activation among the substantia nigra, nucleus accumbens, subthalamic nucleus, putamen, pallidum, and caudate. We conducted two multivariable linear regression models: (1) with gait speed as the dependent variable and connectivity, demographics, WMH, GMV, and locomotor risk factors as independent variables and (2) with basal ganglia connectivity as the dependent variable and demographics, WMH, GMV, and locomotor risk factors as independent variables. RESULTS: We identified two clusters of basal ganglia connectivity: high and low without a distinct spatial distribution allowing us to compute an average connectivity index of the entire basal ganglia regional connectivity (representing a continuous measure). Lower connectivity was associated with slower gait, independent of other locomotor risk factors, including WMH; the coefficient of this association was similar to those of other locomotor risk factors. Lower connectivity was significantly associated with lower BMI and greater WMH. CONCLUSIONS: Lower resting state basal ganglia connectivity is associated with slower gait speed. Its contribution appears comparable to WMH and other locomotor risk factors. Future studies should assess whether promoting higher basal ganglia connectivity in older adults may reduce age-related gait slowing.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Velocidade de Caminhada , Idoso , Gânglios da Base/diagnóstico por imagem , Feminino , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética , Fatores de Risco
4.
Diabet Med ; 36(9): 1168-1175, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30552772

RESUMO

AIM: To assess the prevalence of, and risk factors for, depressive symptoms, comparing a sample of middle-aged adults with and without juvenile-onset Type 1 diabetes mellitus, and to determine if depressive symptoms were associated with white matter hyperintensity volume among those with Type 1 diabetes. METHODS: Depressive symptoms and white matter hyperintensities were compared between adults (age range 30-65 years) with juvenile-onset Type 1 diabetes (n=130) and adults without Type 1 diabetes (n=133). The association of Type 1 diabetes with depression was computed before and after adjustment for white matter hyperintensities. Among the Type 1 diabetes group, the primary associations of interest were between depressive symptoms (Beck Depression Inventory score ≥10) and white matter hyperintensities (n=71), hyperglycaemia and physical activity. Associations between depressive symptoms and diabetes-related complications, cognitive impairment, smoking and self-reported disability were examined. Analyses were controlled for education, sex, age and antidepressant use. RESULTS: Depressive symptoms were more prevalent among those with vs those without Type 1 diabetes (28% vs 3%; P<0.001). White matter hyperintensities explained 40% of the association of Type 1 diabetes with depressive symptoms, while Type 1 diabetes had a direct effect of 68% on depressive symptoms. Among those with Type 1 diabetes, depressive symptoms were related to white matter hyperintensity volume, a 16-year average HbA1c ≥58 mmol/mol (7.5%), and lower physical activity levels. Associations with other characteristics were not significant. CONCLUSION: These findings suggest a cerebrovascular origin for depressive symptoms in adults with Type 1 diabetes, perhaps triggered by hyperglycaemia. Future longitudinal studies should investigate whether targeting hyperglycaemia and physical inactivity alleviates depressive symptoms, possibly by slowing the development of cerebral microvascular disease, in people with Type 1 diabetes.


Assuntos
Transtornos Cerebrovasculares/epidemiologia , Depressão/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Angiopatias Diabéticas/epidemiologia , Adulto , Idoso , Antidepressivos/uso terapêutico , Estudos de Casos e Controles , Transtornos Cerebrovasculares/complicações , Depressão/tratamento farmacológico , Depressão/etiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/psicologia , Angiopatias Diabéticas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estados Unidos/epidemiologia
5.
Aging Clin Exp Res ; 30(6): 633-641, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28836178

RESUMO

BACKGROUND: In older adults, impaired control of standing balance in the lateral direction is associated with the increased risk of falling. Assessing the factors that contribute to impaired standing balance control may identify areas to address to reduce falls risk. AIM: To investigate the contributions of physiological factors to standing lateral balance control. METHODS: Two hundred twenty-two participants from the Pittsburgh site of the Health, Aging and Body Composition Study had lateral balance control assessed using a clinical sensory integration balance test (standing on level and foam surface with eyes open and closed) and a lateral center of pressure tracking test using visual feedback. The center of pressure was recorded from a force platform. Multiple linear regression models examined contributors of lateral control of balance performance, including concurrently measured tests of lower extremity sensation, knee extensor strength, executive function, and clinical balance tests. Models were adjusted for age, body mass index, and sex. RESULTS: Larger lateral sway during the sensory integration test performed on foam was associated with longer repeated chair stands time. During the lateral center of pressure tracking task, the error in tracking increased at higher frequencies; greater error was associated with worse executive function. The relationship between sway performance and physical and cognitive function differed between women and men. DISCUSSION: Contributors to control of lateral balance were task-dependent. Lateral standing performance on an unstable surface may be more dependent upon general lower extremity strength, whereas visual tracking performance may be more dependent upon cognitive factors. CONCLUSIONS: Lateral balance control in ambulatory older adults is associated with deficits in strength and executive function.


Assuntos
Acidentes por Quedas , Equilíbrio Postural/fisiologia , Desempenho Psicomotor/fisiologia , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Retroalimentação Sensorial , Feminino , Humanos , Extremidade Inferior , Masculino , Percepção , Postura/fisiologia , Pressão
6.
J Prev Alzheimers Dis ; 4(1): 44-50, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29188859

RESUMO

OBJECTIVES: We examined whether multiple domains of baseline cognitive performance were associated with prospective physical activity (PA) adherence in the Lifestyle Interventions and Independence for Elders Pilot study (LIFE-P). DESIGN, SETTING, PARTICIPANTS: The LIFE-P study was a single-blind, multicenter, randomized controlled trial of a PA intervention compared to a successful aging educational intervention in sedentary, mobility-limited older adults. INTERVENTION: A 12-month structured, moderate-intensity, multi-modal PA program that included walking, resistance training, and flexibility exercises. For the first 2 months (adoption), 3 center-based exercise sessions (40-60 min) / week were conducted. During the next 4 months (transition), center-based sessions were conducted 2 times / week. The subsequent maintenance phase consisted of optional once-to-twice-per-week center-based sessions and home-based PA. MEASUREMENTS: Tests of executive and global cognitive functioning, working memory and psychomotor speed were administered at baseline. Median test scores were used to dichotomize participants into low or high cognitive performance groups. RESULTS: 52 mobility-limited older adults (age: 76.9 ±5 yrs) were randomized to the PA arm of LIFE-P. Compared to participants with high cognitive performance, participants with low performance had similar PA adherence rates (all P ≥ 0.34). Furthermore, weak and non-significant univariate relationships were elicited between all measures of cognition and overall PA adherence levels (r values ranged: -0.20 to 0.12, P ≥ 0.12). CONCLUSION: These data suggest that cognitive performance does not limit long-term PA adherence in mobility-limited older adults. Additional studies in larger cohorts are warranted to verify these findings.


Assuntos
Cognição , Disfunção Cognitiva , Terapia por Exercício/psicologia , Exercício Físico , Cooperação do Paciente/psicologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Educação em Saúde , Humanos , Masculino , Memória de Curto Prazo , Limitação da Mobilidade , Testes Neuropsicológicos , Projetos Piloto , Comportamento Sedentário , Método Simples-Cego
7.
AJNR Am J Neuroradiol ; 38(10): 1923-1928, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28775055

RESUMO

BACKGROUND AND PURPOSE: Traditional neuroimaging markers of small-vessel disease focus on late-stage changes. We aimed to adapt a method of venular assessment at 7T for use in older adults. We hypothesized that poorer venular morphologic characteristics would be related to other small-vessel disease neuroimaging markers and a higher prevalence of small-vessel disease-Alzheimer disease risk factors. MATERIALS AND METHODS: Venules were identified in periventricular ROIs on SWI and defined as tortuous or straight. The tortuosity ratio was defined as total tortuous venular length divided by total straight venular length. White matter hyperintensity burden (visually rated from 0 to 3) and the number of microbleeds (0, 1, >1) were determined. Differences in tortuous and straight venular lengths were evaluated. Relationships with demographic variables, allele producing the e4 type of apolipoprotein E (APOE4), growth factors, pulse pressure, physical activity, and Modified Mini-Mental State Examination were assessed via Spearman correlations. RESULTS: Participants had 42% more tortuous venular tissue than straight (median, 1.42; 95% CI, 1.13-1.62). APOE4 presence was associated with a greater tortuosity ratio (ρ = 0.454, P = .001), and these results were robust to adjustment for confounders and multiple comparisons. Associations of the tortuosity ratio with sex and vascular endothelial growth factor did not survive adjustment. Associations of the tortuosity ratio with other variables of interest were not significant. CONCLUSIONS: Morphologic measures of venules at 7T could be useful biomarkers of the early stages of small-vessel disease and Alzheimer disease. Longitudinal studies should examine the impact of apolipoprotein E and vascular endothelial growth factor on the risk of venular damage.


Assuntos
Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Feminino , Humanos , Masculino , Fatores de Risco
8.
Org Biomol Chem ; 13(42): 10437-41, 2015 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-26400551

RESUMO

We report the rational design, based on docking simulations, and synthesis of the first fluorescent and selective probe of GPER for bioimaging purposes and functional dissecting studies. It has been conceived as a Bodipy derivative and obtained by accessible and direct synthesis. Its optical properties have been measured in different solvents, showing insensitivity to their polarity. Its binding to GPER was achieved by competition assays with [3H]E2 and [5,6-3H] nicotinic acid in ER-negative and GPER-positive SkBr3 breast cancer cells. SkBr3 cells, transfected with a GPER expression vector containing a FLAG tag, were used to confirm that the fluorophore binds to GPER in a specific manner.


Assuntos
Compostos de Boro/química , Técnicas de Química Analítica/métodos , Corantes Fluorescentes/química , Receptores Acoplados a Proteínas G/análise , Sítios de Ligação , Células Cultivadas , Técnicas de Química Analítica/instrumentação , Corantes Fluorescentes/síntese química , Humanos , Modelos Moleculares , Estrutura Molecular
9.
Curr Med Chem ; 21(5): 630-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23862621

RESUMO

Several substances widely dispersed in the environment including hormones, industrial by-products and pollutants exert hormone like activity affecting steroid-responsive physiological systems. These compounds, named endocrine disruptors, are suspected to affect the mammalian reproductive system. However it is still unclear whether these substances are able to elicit estrogen like activity at the low concentrations encountered in the environment. Here we compare the effects of the endocrine disruptor nonylphenol with the effects elicited by 17-ß-estradiol on gene transcription in the human breast cancer cell line MCF7. The correlation of the nonylphenol induced gene expression alterations with a reference profile of estradiol treated cells shows that nonylphenol at a concentration of 100 nM exerts a significant effect on estrogen responsive gene transcription in MCF7 cells. Most of the genes regulated by 17-ß-estradiol respond to the nonylphenol in the same direction though to a much lesser extent. Molecular modeling of the potential interaction of nonylphenol with the estrogen receptor α shows that nonylphenol is likely to bind to the estrogen receptor α.


Assuntos
Disruptores Endócrinos/farmacologia , Fenóis/farmacologia , Receptores de Estrogênio/metabolismo , Transcrição Gênica/efeitos dos fármacos , Sítios de Ligação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Disruptores Endócrinos/química , Estradiol/farmacologia , Receptor alfa de Estrogênio/química , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Fenóis/química , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Estrogênio/genética , Transativadores/genética , Transativadores/metabolismo
10.
Curr Med Chem ; 21(9): 1129-45, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24304271

RESUMO

Observations on the role of ovarian hormones in breast cancer growth, as well as interest in contraception, stimulated research into the biology of estrogens. The identification of the classical receptors ERα and ERß and the transmembrane receptor GPER and the resolution of the structure of the ligand bound to its receptor established the principal molecular mechanisms of estrogen action. The presence of estrogen-like compounds in many plants used in traditional medicine or ingested as food ingredients, phytoestrogens, as well as the estrogenic activities of many industrial pollutants and pesticides, xenoestrogens, have prompted investigations into their role in human health. Phyto- and xenoestrogens bind to the estrogen receptors with a lower affinity than the endogenous estrogens and can compete or substitute the hormone. Xenoestrogens, which accumulate in the body throughout life, are believed to increase breast cancer risk, especially in cases of prenatal and prepuberal exposure whereas the role of phytoestrogens is still a matter of debate. At present, the application of phytoestrogens appears to be limited to the treatment of post-menopausal symptoms in women where the production of endogenous estrogens has ceased. In this review we discuss chemistry, structure and classification, estrogen signaling and the consequences of the interactions of estrogens, phytoestrogens and xenoestrogens with their receptors, the complex interactions of endogenous and exogenous ligands, the evaluation of the health risks related to xenoestrogens, and the perspectives toward the synthesis of potent third generation selective estrogen receptor modulators (SERMs).


Assuntos
Neoplasias da Mama/metabolismo , Disruptores Endócrinos/metabolismo , Fitoestrógenos/metabolismo , Animais , Humanos , Receptores de Estrogênio/metabolismo , Fatores de Risco , Transdução de Sinais
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