Estresse oxidativo, envelhecimento renal e doença renal crônica terminal / Oxidative stress, renal aging and end-stage renal disease

O mundo está passando por uma transformação demográfica. O número de idosos vem aumentando progressivamente nas últimas décadas, levando a um crescente interesse pelo entendimento do processo de envelhecimento, que é universal, complexo e multifacetado. O estresse oxidativo, uma das teorias biológicas do envelhecimento mais aceita na atualidade, pode estar relacionado à senescência renal. Do ponto de vista do envelhecimento renal, sabe-se que o rim apresenta alterações morfológicas e funcionais com o avançar da idade que podem ser agravadas pela presença de comorbidades. A doença renal crônica terminal vem assumindo grande importância para a saúde pública, visto que a sua incidência e prevalência têm aumentado de forma significativa nas últimas décadas, principalmente na população idosa. Objetiva-se abordar a senescência renal e o desenvolvimento da doença renal crônica terminal e as possíveis relações com a teoria do estresse oxidativo.(AU)

The world is undergoing a demographic change. The number of elderly has increased progressively in the last few decades, leading to a growing interest in understanding the aging process, which is universal, complex and multifaceted. Oxidative stress, one of the currently most accepted biological theories of aging, may be related to renal senescence. From the standpoint of renal aging it is known that the kidney presents morphological alterations and, as people grow older, they may become worse due to the presence of comorbidities. End stage renal disease has become increasingly important in public health, since its incidence and prevalence have grown significantly in the last few decades, especially in the elderly population. The intention of this paper is to discuss renal senescence and the development of end stage renal disease, and its possible relations with the theory of oxidative stress.(AU)

Estresse oxidativo, envelhecimento renal e doença renal crônica terminal / Oxidative stress, renal aging and end-stage renal disease

O mundo está passando por uma transformação demográfica. O número de idosos vem aumentando progressivamente nas últimas décadas, levando a um crescente interesse pelo entendimento do processo de envelhecimento, que é universal, complexo e multifacetado. O estresse oxidativo, uma das teorias biológicas do envelhecimento mais aceita na atualidade, pode estar relacionado à senescência renal. Do ponto de vista do envelhecimento renal, sabe-se que o rim apresenta alterações morfológicas e funcionais com o avançar da idade que podem ser agravadas pela presença de comorbidades. A doença renal crônica terminal vem assumindo grande importância para a saúde pública, visto que a sua incidência e prevalência têm aumentado de forma significativa nas últimas décadas, principalmente na população idosa. Objetiva-se abordar a senescência renal e o desenvolvimento da doença renal crônica terminal e as possíveis relações com a teoria do estresse oxidativo.

The world is undergoing a demographic change. The number of elderly has increased progressively in the last few decades, leading to a growing interest in understanding the aging process, which is universal, complex and multifaceted. Oxidative stress, one of the currently most accepted biological theories of aging, may be related to renal senescence. From the standpoint of renal aging it is known that the kidney presents morphological alterations and, as people grow older, they may become worse due to the presence of comorbidities. End stage renal disease has become increasingly important in public health, since its incidence and prevalence have grown significantly in the last few decades, especially in the elderly population. The intention of this paper is to discuss renal senescence and the development of end stage renal disease, and its possible relations with the theory of oxidative stress.

Morphological changes in the mandible of male mice associated with aging and biomechanical stimulus.

Degenerative changes in the temporomandibular joint (TMJ) associated with aging can affect mandibular shape and reduce growth potential when stimulated by functional appliance therapy. This study was designed to evaluate the morphological changes in the mandibles of male mice associated with aging and biomechanical stimulus. Every 3 days over the course of 1 month, the lower incisors were trimmed by 1 mm to induce mandibular advancement (MA) when the animal was feeding. The left mandibles of the 23 experimental and 27 control animals were subsequently dissected, and digital images were obtained to analyze nine linear/angular measurements. Because mandibular morphology depends on the maintenance of condylar cartilage, the surfaces of the condylar cartilage and the ascending ramus of the mandible were also analyzed by scanning electron microscopy (SEM). The linear measurements of the mandible showed changes according to age in the control group and a growth response in the mandibular condyle in 7- and 15-month-old mice after MA. Moreover, SEM analysis revealed depressions in the anterior region of the condylar cartilage and inclined vascular grooves in the ascending ramus in the 7- and 15-month-old experimental mice. Although the growth potential is reduced in mice after 6 months of age, the results showed that continuous growth of the mandible occurs after maturation, except in the condyle, and that biomechanical stimulus of the TMJ of male mice leads to condylar growth. These results suggest that mature and old individuals can favorably respond to maxillary functional orthopedic therapy.

Mandibular advancement and morphological changes in the mandibles of female mice of different ages.

Mandibular advancement (MA) by means of functional orthopedic techniques is currently used in young patients to stimulate mandibular growth. The aim of this study was to evaluate the morphological changes in the mandibles of 2-, 7-, and 16-month-old female mice after MA. Every 3 days during 1 month, the lower incisors were trimmed by 1mm to induce protrusion when the animal was feeding. The left mandibles of the 30 experimental and 28 control individuals were subsequently dissected and digital images were obtained to analyze nine linear/angular measurements. The condylar microstructure was also analyzed by scanning electron microscopy (SEM). The linear/angular measurements showed a growth response in different mandibular regions in 2- and 16-month-old individuals. SEM showed that, in the 7-month-old mice, the condylar cartilage had regenerated in the treated individuals but not in the controls. The results suggest that MA produces mandibular growth in 2- and 16-month-old female mice. Although there was no mandibular growth in 7-month-old mice, regeneration of the condylar cartilage was detected, thus demonstrating that different responses to the MA stimulus occur in female mice of different ages.