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1.
Biol Reprod ; 110(4): 660-671, 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38480995

RESUMEN

Cellular senescence (CS) is the state when cells are no longer capable to divide even after stimulation with grown factors. Cells that begin to undergo CS stop in the cell cycle and enter a suspended state without committing to programmed cell death. These cells assume a specific phenotype and influence their microenvironment by secreting molecules and extracellular vesicles that are part of the so-called senescent cell-associated secretory phenotype (SASP). Cellular senescence is intertwined with physiological and pathological conditions in the human organism. In terms of reproduction, senescent cells are present from reproductive tissues and germ cells to gestational tissues, and participate from fertilization to delivery, going through adverse reproductive outcomes such as pregnancy losses. Furthermore, various SASP molecules are enriched in gestational tissues throughout pregnancy. Thus, the aim of this review is to provide a basis about the features and potential roles played by CS throughout the reproductive process, encompassing its implication in each step of it and proposing a way to manage it in adverse reproductive contexts.


Asunto(s)
Senescencia Celular , Vesículas Extracelulares , Humanos , Senescencia Celular/fisiología , Fenotipo , Vesículas Extracelulares/metabolismo , Transporte Biológico , Reproducción
2.
J Stomatol Oral Maxillofac Surg ; 123(4): 440-447, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34520932

RESUMEN

Nonsurgical cosmetic treatments have significantly increased over the last decade. Therefore, this study aims to review the features that should be considered in orofacial esthetic procedures, thorough of a proposal of a new concept called the tissue mimicry concept (MIMT concept) and filling techniques. The MIMT concept described in this article comprises knowledge about anatomy of the face and associated structures, understanding of aging and how this process affects the facial tissues interactions (skin, subcutaneous tissues, muscles, and bones), interpretation of facial analysis, comprehension of dermal fillers characteristics and discernment of the correct filling technique for each region. Based on these variables the MIMT concept proposes the implantation of the minimum-effective quantity of acid hyaluronic fillers (HA) with different physical, chemical and rheological properties (complex viscosity and elastic modulus) in the correct layers; in order to optimize their performance resulting in a natural appearance with fewer risks of adverse events. the versatility, acceptable safety profile, biocompatibility and greater patient compliance presented in the Restylane® line (by Galderma) should be taken in consideration, since the use of a proper HA is noteworthiness. The Non-Animal Stabilized Hyaluronic Acid Tecnology (NASHA®) and the Optimal Balance Technology (OBT®), which make up this line of fillers, allow us to have very firm to very flexible gels, with different particle sizes, with an optimal concentration of HA and with viscoelastic and biocompatible characteristics according to the region of the treated face.


Asunto(s)
Técnicas Cosméticas , Envejecimiento de la Piel , Estética Dental , Humanos , Ácido Hialurónico/análogos & derivados , Ácido Hialurónico/química , Rejuvenecimiento , Tecnología
3.
Arq. bras. cardiol ; Arq. bras. cardiol;116(1): 37-47, Jan. 2021. tab, graf
Artículo en Inglés, Portugués | LILACS | ID: biblio-1152963

RESUMEN

Resumo Fundamento Doenças cardiovasculares (DCV) são uma das principais causas de mortalidade e morbidade em todo o mundo. O envelhecimento biológico tem sido associado à ocorrência de resultados cardiovasculares. Entretanto, o mecanismo subjacente desse processo ainda é desconhecido. Objetivos Buscamos avaliar se a senescência das células sanguíneas mononucleares periféricas (CSMP) e biomarcadores endoteliais poderiam influenciar o risco cardiovascular (CV) e ser marcadores adequados para a detecção precoce de doenças cardiovasculares em adultos. Métodos Neste estudo transversal, pacientes livres de DCV foram classificados como baixo (n=32) e alto (n=28) escore de risco intracardaco (IHR) A senescência das CSMP foi avaliada estimando-se a atividade de telomerase (AT) e detectando-se a presença de células senescentes e disfunção endotelial, estimando-se a concentração de nitrito e nitrato e a capacidade antioxidante total (CAT). A análise estatística foi realizada com o software SPSS, versão 16.0 (SPSS Inc., Chicago, IL). Todos os p-valores <0,05 foram considerados estatisticamente significativos. Resultados A senescência de CSMP de 0,95 [p-valor = 0,0001; 95% IC (0,874-1,026)] foi um indicador significativo de pacientes com escore de IHR mais alto, com um valor de corte de 21,65, com sensibilidade e especificidade de 92% e 88% respectivamente. Identificou-se que a senescência de CSMP, nitrito e nitrato, e AT eram independentemente associadas a um escore de IHR alto. Conclusão Os status de nitrito e nitrato e AT, e a senescência de CSMP são medidas adequadas para prever o alto risco cardiovascular em adultos com risco CV. Entretanto devem ser realizados estudos de acompanhamento de longo prazo para confirmar esses achados. (Arq Bras Cardiol. 2021; 116(1):37-47)


Abstract Background Cardiovascular diseases (CVD) are one of the leading causes of mortality and morbidity worldwide. Biological aging has been associated with the occurrence of adverse cardiovascular outcomes; however, the underlying mechanism of this process remains unknown. Objectives This study sought to evaluate if peripheral blood mononuclear cell (PBMC) senescence and endothelial biomarkers could influence cardiovascular (CV) risk and be suitable markers for the early detection of cardiovascular diseases in adults. Methods In this cross-sectional study patients free of CVD were classified as lower (n=32) and higher Interheart Risk (IHR) scores (n=28). PBMC senescence was assessed by estimating the telomerase activity (TA) and detecting the presence of senescent cells and endothelial dysfunction by estimating the concentration of nitrite and nitrate and of total antioxidant capacity (TAC). Statistical analysis was performed with SPSS version 16.0 (SPSS Inc., Chicago, IL). All p-values <0.05 were considered statistically significant. Results PBMC senescence 0.95 [p-value = 0.0001; 95% CI (0.874-1.026)] was a significant predictor of patients with higher IHR scores with a cut-off value of 21.65 with a sensitivity and specificity of 92% and 88% respectively. PBMC senescence, nitrite and nitrate and TA were found to be independently associated with high IHR scores. Conclusion PBMC senescence, TA and nitrite, and nitrate status are suitable measures to predict high cardiovascular risk in adults with CV risk. Nevertheless, long-term follow-up studies are needed to confirm these findings. (Arq Bras Cardiol. 2021; 116(1):37-47)


Asunto(s)
Humanos , Adulto , Leucocitos Mononucleares , Enfermedades Cardiovasculares/diagnóstico , Estudios Transversales , Factores de Riesgo , Factores de Riesgo de Enfermedad Cardiaca
4.
Rev. Inst. Med. Trop. São Paulo (Online) ; 60: 16, Apr. 2018. ilus, tab
Artículo en Inglés | Sec. Est. Saúde SP, SESSP-IIERPROD, Sec. Est. Saúde SP | ID: biblio-1022175

RESUMEN

OBJECTIVE: We evaluated the association between cognitive deficits and leukocyte telomere length (LTL) in HIV-1-infected individuals. DESIGN: 73 HIV-1-infected patients undergoing neuropsychological evaluation and 91 healthy controls were included in this study. Fifteen HIV-1 positive patients did not have cognitive disorders whereas 26 had asymptomatic neurocognitive disorder (ANI), 13 presented mild to moderate neurocognitive disorder (MND), and 10 had HIV-associated dementia (HAD). METHODS: DNA from the peripheral blood of HIV-1-infected patients was used for measurement of telomere length by real-time PCR. HIV-1 viral load was determined in blood. RESULTS: LTL decreased with age in healthy controls (p=0.0001). Regardless of the HIV status, age-matched LTL from HIV patients, including those with ANI and MND, were shortened in comparison to the healthy control group (p=0.0073); however, no association was found among the HIV-1-infected individuals with cognitive deficits (p=0.01). In addition, no gender-related association with LTL was observed (p=0.80), smoking, physical exercise, and plasma viral load were not correlated to telomere length (p=0.66). CONCLUSIONS: We concluded that leukocyte telomere length may not be a marker of cellular senescence in individuals with HIV infection and neurocognitive disorders


Asunto(s)
Humanos , Masculino , Femenino , Infecciones por VIH , Complejo SIDA Demencia , Telómero , Disfunción Cognitiva
5.
Braz. dent. j ; Braz. dent. j;27(5): 485-491, Sept.-Oct. 2016. graf
Artículo en Inglés | LILACS | ID: biblio-828049

RESUMEN

Abstract Fibroblasts participate in the wound repair process through proliferation and migration as well as the synthesis of factors growth and extracellular matrix molecules. However, cell aging and the individual himself can lead to reduction of cell functions and consequently, the ability of tissue repair. This study evaluated the activity of gingival fibroblasts from young (Y) and elderly (Y) patients and their responsiveness to tumor necrosis factor alpha (TNF-a). Gingival fibroblasts were isolated from six patients (3Y; and 3E) and seeded in complete culture medium (DMEM). For cell viability analysis, total protein production and collagen synthesis, fibroblasts were cultured in 96-well plates for 24, 48 or 72 h (n=36). Cell responses to TNF-a, was evaluated by application of this cytokine to cultured cells (100 ng/mL) for 24 h, followed by evaluation of reactive oxygen species (ROS), nitric oxide (NO) and CCL5 production (n=36). Data were analyzed by Kruskal-Wallis and the Mann-Whitney U tests (a = 0.05). Viability of E fibroblasts was higher than Y fibroblasts for 24 and 48 h, but these cells showed gradual reduction of viability over the course of time. For Y cells, reduced collagen synthesis was observed at 48 h. No difference was observed in ROS production for both cells after TNF-a exposure. However, both cultures showed increased production of NO and CCL5 in the presence of TNF-a. Functional differences and distinct responsiveness to TNF-a were observed according to patient's age.


Resumo Fibroblastos participam no processo de reparação de ferida através da proliferação e migração, bem como a síntese de fatores de crescimento e moléculas da matriz extracelular. No entanto, o envelhecimento celular e o próprio indivíduo podem levar à redução de funções celulares e, consequentemente, a capacidade de reparação de tecidos. Este estudo avaliou a atividade dos fibroblastos gengivais de pacientes jovens (J) e idosos (I) e sua capacidade de resposta frente ao fator de necrose tumoral alfa (TNF-a). Fibroblastos gengivais foram isolados de seis pacientes (3J e 3I) e semeados em meio de cultura completo (DMEM). Para a análise de viabilidade celular, a produção de proteína total e a síntese de colágeno, fibroblastos foram cultivados em placas de 96 poços, durante 24, 48 ou 72 h (n = 36). Respostas celulares frente ao TNF-a, foram avaliadas por aplicação desta citocina (100 ng/mL) nas células cultivadas durante 24 h, seguida por avaliação de espécies reativas de oxigênio (EROs), produção de óxido nítrico (NO) e produção CCL5 (n= 36). Os dados foram analisados por testes de Kruskal-Wallis e Mann-Whitney U (a = 0,05). A viabilidade de fibroblastos I foi mais elevada do que os fibroblastos J para 24 e 48 h, mas estas células mostraram uma redução gradual de viabilidade ao longo do tempo. Para as células de J, foi observada redução da síntese de colágeno em 48 h. Não foi observada diferença na produção de EROs para ambas as células após exposição ao TNF-a. No entanto, ambas as culturas apresentaram aumento da produção de NO e CCL5 na presença de TNF-a. Diferenças funcionais e alteração na capacidade de resposta ao TNF-a foram observadas de acordo com a idade do paciente.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Encía/citología , Fibroblastos/citología
7.
Rev. cienc. salud (Bogotá) ; 9(3): 219-228, dic. 2011. graf, tab
Artículo en Inglés | LILACS, COLNAL | ID: lil-650015

RESUMEN

GAPDH can bind single-strand telomere DNA both in vitro and in vivo. Thus, it was hypothesised that GAPDH has an important role in protecting the telomeres, role that could be shared with TRF2, a well-known telomeric protein involved in a myriad of functions related to telomere homeostasis. Objective: The aim of this study was to determine if there was a correlation between the expression of these genes in the in vitro ovarian surface epithelium. Materials and methods: The relative expression of each gene was established by qRT-PCR in primary cell cultures of the ovarian surface epithelium from 22 healthy mestizo Colombian donors. Results: The Kendall and Spearman non-parametric tests established a significant correlation between the levels of expression in subsequent passages of the cell line, in an age-independent way. Conclusion: Our findings suggest a synergistic effect between TRF2 and GAPDH that could counter telomere shortening in vitro.


Se ha demostrado que la proteína GAPDH se puede unir al ADN telomérico de cadena sencilla, tanto in vitro como in vivo. Por lo tanto, se ha planteado la hipótesis de que la GAPDH juega un papel importante en la protección de los telómeros, papel que podría ser compartido con la TRF2, proteína que participa en una gran variedad de funciones relacionadas con la homeostasis telomérica. Objetivo: el objetivo de este estudio fue determinar si existe una correlación entre la expresión de ambos genes en el epitelio superficial del ovario in vitro. Materiales y métodos: la expresión relativa de cada gen fue establecida mediante qRT-PCR, en cultivos primarios de células del epitelio superficial del ovario provenientes de un grupo de 22 donantes colombianas mestizas sanas. Resultados: las pruebas no paramétricas de Kendall y Spearman permitieron establecer que existe una correlación significativa entre los niveles de expresión de GAPDH y TRF2 a lo largo de la historia replicativa de los cultivos, en forma independiente de la edad de las donantes. Conclusión: nuestros resultados sugieren un efecto sinérgico entre TRF2 y GAPDH, que podría estar orientado a contrarrestar la reducción de los telómeros in vitro.


Tem se demonstrado que GAPDH pode-se unir ao DNA telomérico de cadeia simples, tanto in vitro quanto in vivo. Portanto, tem se apresentado a hipótese de que GAPDH joga um papel importante na proteção dos telómeros, papel que poderia ser compartilhado com TRF2, proteína que participa em uma grande variedade de funções relacionadas com a homeostase telomérica. Objetivo. O objetivo deste estudo foi determinar se existe uma correlação entre a expressão de ambos os genes no epitélio superficial do ovário in vitro. Materiais e métodos: A expressão relativa de cada gene foi estabelecida mediante qRT-PCR em cultivos primários de células do epitélio superficial do ovário provenientes de um grupo de 22 doadoras colombianas mestiças sanas. Resultados. As provas não paramétricas de Kendall e Spearman permitiram estabelecer que existe uma correlação significativa entre os níveis de expressão de GAPDH e TRF2 ao longe da história replicativa dos cultivos, em forma independente da idade das doadoras. Conclusão. Nossos resultados sugerem um efeito sinérgico entre TRF2 e GAPDH que poderia estar orientado a contra-arrestar a redução dos telómeros in vitro.


Asunto(s)
Humanos , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Expresión Génica , Técnicas In Vitro , Telómero , Senescencia Celular , Colombia , Cultivo Primario de Células , Correlación de Datos
8.
Ciênc. Saúde Colet. (Impr.) ; Ciênc. Saúde Colet. (Impr.);15(6): 2845-2857, set. 2010. ilus, graf, tab
Artículo en Portugués | LILACS | ID: lil-559816

RESUMEN

O artigo apresenta uma revisão das teorias biológicas do envelhecimento e discute os mecanismos relevantes para explicar o processo. Iniciando com as teorias evolutivas, o texto explora os mecanismos moleculares-celulares e apresenta a perspectiva das teorias sistêmicas. O conhecimento sobre a senescência desenvolve-se na direção de uma abordagem integrativa. A complexidade etiológica do fenômeno é um desafio para os pesquisadores.


Abstract The article reviews the major biological theories of aging, and discusses the most relevant mechanisms to explain the aging process. It begins with the evolutionary theories, explores the molecular-cellular mechanisms, and presents the perspective of the systemic theories. The complex etiology of aging is a challenge to the researchers. The knowledge on that phenomenon develops towards an integrative approach.


Asunto(s)
Humanos , Envejecimiento/fisiología
9.
Einstein (Säo Paulo) ; 8(2)abr.-jun. 2010.
Artículo en Inglés, Portugués | LILACS | ID: lil-550968

RESUMEN

Pulmonary emphysema is a chronic obstructive disease, resulting from important alterations in the whole distal structure of terminal bronchioles, either by enlargement of air spaces or by destruction of the alveolar wall, leading to loss of respiratory surface, decreased elastic recoil and lung hyperinflation. For many years, the hypothesis of protease-antiprotease unbalance prevailed as the central theme in the pathogenesis of pulmonary emphysema. According to this hypothesis, the release of active proteolytic enzymes, produced mainly by neutrophils and macrophages, degrades the extracellular matrix, affecting the integrity of its components, especially collagen and elastic fibers. However, new concepts involving cellular and molecular events were proposed, including oxidative stress, cell apoptosis, cellular senescence and failed lung tissue repair. The aim of this review paper was to evaluate the cellular and molecular mechanisms seen in the pathogenesis of pulmonary emphysema.


O enfisema pulmonar é uma doença obstrutiva crônica, resultante de importantes alterações de toda a estrutura distal do bronquíolo terminal, seja por dilatação dos espaços aéreos, seja por destruição da parede alveolar, ocasionando a perda da superfície respiratória, diminuição do recolhimento elástico e hiperinsuflação pulmonar. Por muitos anos, a hipótese do desequilíbrio enzimático proteinase-antiproteinase prevaleceu como tema central na patogenia do enfisema. De acordo com essa hipótese, a liberação de enzimas proteolíticas ativas, produzidas principalmente por macrófagos e neutrófilos, degrada a matriz extracelular, afetando a integridade de seus componentes, particularmente as fibras colágeno e elástica. Entretanto, novos conceitos envolvendo eventos celulares e moleculares foram propostos, incluindo o estresse oxidativo, a apoptose celular, a senescência celular e a falha no processo de reparo do tecido pulmonar. O objetivo deste artigo de revisão foi avaliar os mecanismos celulares e moleculares da patogenia do enfisema pulmonar.


Asunto(s)
Humanos , alfa 1-Antitripsina , Apoptosis , Senescencia Celular , Estrés Oxidativo , Enfisema Pulmonar
10.
Rev. ing. bioméd ; 2(4): 67-77, graf
Artículo en Español | LILACS | ID: lil-773341

RESUMEN

El proceso biológico de remodelamiento óseo ocurre naturalmente todos los días como un proceso de optimización. El algoritmo de autómatas celulares híbridos fue desarrollado para simular ese proceso funcional adaptativo en el hueso a nivel de tejido. En el algoritmo de autómatas celulares híbridos, los osteocitos se representan por un autómata que detecta estímulo mecánico. Esta metodología se ha utilizado para predecir la adaptación de hueso trabecular a los cambios en su ambiente físico. Adicionalmente a este algoritmo se incorporaron factores a los que se encuentra sometido el hueso, como las microgrietas, apoptosis y envejecimiento celular. Para incorporar estos últimos factores se toman estudios preliminares de otros autores donde las microgrietas se analizan con las leyes de la mecánica de fractura, así como también un análisis del esfuerzo cortante en cada autómata se usó para obtener la simulación de la apoptosis, y para el envejecimiento se empleó una función escalonada de la variación de la densidad promedio. En los resultados obtenidos se encuentran incrementos en la energía de deformación y decrementos en la masa, que son consecuencia directa de la concentración de esfuerzos. Igualmente, se observa que la estructura puede reponerse a los factores mencionados, lo que concuerda con estudios experimentales de algunos autores.


A biological process of bone remodeling happens everyday naturally like an optimization process. Hybrid cellular automaton algorithm was developed to simulate this adaptative functional process at tissue level. In the hybrid cellular automaton algorithm, osteocytes are represented by an automaton that senses the mechanical stimulus. This methodology has been used to predict trabecular bone adaptation according to changes in the physic environment. Natural factors like microcracks, apoptosis, and cell aging are incorporated to the algorithm. To incorporate these last factors, preliminary studies of other authors are taken where microcracks are analyzed by fracture mechanics laws, also shear stress analysis to get apoptosis simulation and for the ageing is used a step function of the media density variation. Results show increments in strain energy and decrements in mass that is direct consequence of the stress concentration. In the same way, is observed that the structure can recover to the effects described, that agrees with the experimental studies of some authors.

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