Report From the 6th International Meeting on Bone Marrow Adiposity (BMA2020)

The 6th International Meeting on Bone Marrow Adiposity (BMA) entitled “Marrow Adiposity: Bone, Aging, and Beyond” (BMA2020) was held virtually on September 9th and 10th, 2020. The mission of this meeting was to facilitate communication and collaboration among scientists from around the world who are interested in different aspects of bone marrow adiposity in health and disease. The BMA2020 meeting brought together 198 attendees from diverse research and clinical backgrounds spanning fields including bone biology, endocrinology, stem cell biology, metabolism, oncology, aging, and hematopoiesis. The congress featured an invited keynote address by Ormond MacDougald and ten invited speakers, in addition to 20 short talks, 35 posters, and several training and networking sessions. This report summarizes and highlights the scientific content of the meeting and the progress of the working groups of the BMA society (http://bma-society.org/).

Bone aging and functional capacity of smokers.

Objetivo: avaliar o conteúdo e densidade mineral óssea relacionada a capacidade funcional de tabagistas. Método: trata-se de estudo transversal, de métodos e procedimentos próprios da pesquisa epidemiológica descritiva e de abordagem quantitativa. A pesquisa realizou-se em um Centro de Referência em Reabilitação e Assistência à Saúde no município de São Paulo. Aplicou-se um questionário sociodemográfico e fatores relacionados, o instrumento Fagerström de avaliação da dependência nicotínica e o teste de caminhada de seis minutos para avaliação da capacidade funcional. Realizou-se Absortometria Radiológica de Raio X de Dupla Energia – de coluna lombar, colo do fêmur e fêmur total. Resultados: avaliaram-se 24 tabagistas com idade entre 45 e 75 anos, de ambos os sexos, idade média de 58,6±5,9 anos, Índice de Massa Corporal médio de 26,7±3,4, a maioria do sexo feminino 16 (66%). Grau de dependência nicotínica prevalente baixa. Houve ainda significante associação entre massa óssea e capacidade funcional entre mulheres tabagistas. Conclusão: houve significante associação entre massa óssea e capacidade funcional entre tabagistas do sexo feminino. Torna-se desejável os prestadores de cuidados de saúde no contexto clínico da reabilitação, empregar sistemas que assegurem abordar outras comorbidades coocorrentes, tais como o tabagismo.

Age-dependent modulation of bone metabolism in zebrafish scales as new model of male osteoporosis in lower vertebrates

After middle age, in human bone, the resorption usually exceeds formation resulting in bone loss and increased risk of fractures in the aged population. Only few in vivo models in higher vertebrates are available for pathogenic and therapeutic studies about bone aging. Among these, male Danio rerio (zebrafish) can be successfully used as low vertebrate model to study degenerative alterations that affect the skeleton during aging, reducing the role of sex hormones. In this paper, we investigated the early bone aging mechanisms in male zebrafish (3, 6, 9 months old) scales evaluating the physiological changes and the effects of prednisolone, a pro-osteoporotic drug. The results evidentiated an age-dependent reduction of the mineralization rate in the fish scales, as highlighted by growing circle measurements. Indeed, the osteoblastic ALP activity at the matrix deposition site was found progressively downregulated. The higher TRAP activity was found in 63% of 9-month-old fish scales associated with resorption lacunae along the scale border. Gene expression analysis evidentiated that an increase of the tnfrsf1b (homolog of human rank) in aging scales may be responsible for resorption stimulation. Interestingly, prednisolone inhibited the physiological growth of the scale and induced in aged scales a more significant bone resorption compared with untreated fish (3.8% vs 1.02%). Bone markers analysis shown a significant reduction of ALP/TRAP ratio due to a prednisolone-dependent stimulation of tnfsf11 (homolog of human rankl) in scales of older fish. The results evidentiated for the first time the presence of a senile male osteoporosis in lower vertebrate. This new model could be helpful to identify the early mechanisms of bone aging and new therapeutic strategies to prevent age-related bone alterations in humans.

Effect of Qing’e Decoction on Leptin/Leptin Receptor and Bone Metabolism in Naturally Aging Rats

Senile osteoporosis (SOP) is a common disease that has decreased bone strength as its main symptom. There is currently no medication that can treat SOP, and traditional Chinese medicine has advantages in slowing down bone aging. The present study aimed to observe the effects of Qing’e decoction on leptin, leptin receptor, sex hormone, and biochemical markers of bone metabolism in naturally aging rats and to explore its mechanism in regulating bone metabolism. The results revealed that, with the increase in age, the bone mineral density (BMD), bone strength, bone trabecula sparse, serum levels of leptin receptor (LEP-R), estradiol (E2), testosterone (T), core binding-factor α-1 (Cbfα-1), collagen-I (COL-I) and osteocalcin (OC), and the mRNA levels of leptin (LEP) and LEP-R in bone tissue decreased, while serum LEP levels increased in the female and male NS groups. The serum levels of LEP, LEP-R, E2, T, osteoprotegerin, Cbfα-1, COL-I, OC and bone alkaline phosphatase, and the mRNA levels of LEP and LEP-R in bone tissue in the female and male QED groups were higher than those in the same age and sex NS group, while the BMD, bone trabecular area percentage, maximum load, and maximum stress in the female and male QED groups were significantly higher than those in the same age and sex NS group. In conclusion, with the increase in age, the bone quality of naturally aging rats decreased gradually. Qing’e decoction can regulate the bone metabolism and increase the bone quality and delay bone aging, which may be achieved by increasing sex hormone, LEP, and LEP-R levels.

Aging bone

This review article deals with the topic of changes in bone tissue in the process of aging of the body. Adipogenesis and osteogenesis are affected at the molecular level, proteins and genes are described, in which somatic mutation can occur during the aging process, resulting in both minor changes and an active loss of bone mineral density. The factors that affect the change in bone mineral density mainly in the elderly, and existing drugs that can slow down osteoporosis are listed. Knowledge of the cellular and molecular mechanisms underlying the aging of bone tissue will contribute to the creation of targeted therapy for osteoporosis, which slows down bone aging and prevents falls and fractures in the elderly people.