Irisin effects on bone: systematic review with meta-analysis of preclinical studies and prospects for oral health

Abstract: Bone quality is an important issue in dentistry. Low bone density may be associated with more severe periodontitis, and may influence implant therapy success. Recent evidence suggests that physical activity can improve alveolar bone quality. Irisin is an exercise-mediated peptide that might be involved in this process. We assessed the effect of exercise and that of intra-peritoneal irisin administration on bone quality in healthy and osteoporosis-induced rodents. This study was registered at PROSPERO (CRD42020184140), and followed PRISMA guidelines. A search by two independent examiners was conducted in five databases and gray literature up to July 2021, without restrictions regarding language or date of publication. Initially, they analyzed retrieved titles and abstracts (n=3,844) based on eligibility criteria. Of this total, 19 studies remained for full-text reading, and 16 proceeded to the data extraction and quality assessment phases. Meta-analyses were conducted (n= 6 studies) to establish the effects of irisin administration on cancellous bone mineral density (BMD). Exercise or irisin administration enhanced bone quality, but the meta-analysis showed that BMD increased only slightly in osteoporotic rodents (BMD: mean difference 0.03 mg/cm3 - 95% CI 0.01-0.05). This indicates that they had no significant benefits on the bones of healthy animals. Implications of key findings evidence the potential of irisin as an agent able to mitigate bone loss caused by osteoporosis, an outcome that could favor dental rehabilitation. More studies investigating the effect of irisin on alveolar bone are needed to elucidate its therapeutic viability and implications.

Experiência subjetiva de idosas durante exercício em ambiente virtual / Subjective experience of older women during exercise in virtual condition / Experiencia subjetiva de mujeres ancianas durante el ejercicio en el ambiente virtual

Os objetivos desse estudo quali-quantitativo foram verificar as experiências subjetivas relacionadas ao exercício em idosas antes e depois da realização de atividade física em ambientes real e virtual, bem como a preferência pelo ambiente. A amostra foi composta por 20 idosas (71,1±6,5 anos) que executaram sessões de dança nos dois ambientes e responderam ao instrumento Subjective Exercise Experiences Scale (SEES) antes e depois da prática. Na situação virtual foi utilizado o jogo Just Dance I do console Wii® da Nintendo. Na situação real, cada participante reproduziu os mesmos movimentos demonstrados pela pesquisadora. Para a análise dos dados da SEES foram utilizados os testes Wilcoxon e Mann-Whitney (p<0,05). Houve redução significativa na pontuação da subescala distress psicológico da SEES após ambas as situações experimentais e aumento no bem-estar positivo apenas em ambiente virtual. A maioria das idosas escolheu o ambiente real como o preferido.

This quali-quantitative study aimed to verify subjective exercise experiences of older women before and after exercise sessions in actual and virtual conditions, as well as, the preferred exercise condition. The sample was composed by 20 older women (71.1±6.5 years-old) who practiced dance sessions in actual and virtual conditions, and answered the Subjective Exercise Experiences Scale (SEES) before and after the activity. In virtual condition it was used the virtual game Just Dance I from the Nintendo Wii® console. In actual condition participants reproduced the same game movements, as demonstrated by the researcher. Wilcoxon and Mann-Whitney tests were used for data analyses (p<0.05). Significant decrease was observed in the psychological distress score of SEES after both conditions. Increase in positive well being score was found only in the virtual condition. Most of the older women chose the actual condition as the preferred.

Los objetivos de este estudio cuali-cuantitativo fueron evaluar las experiencias subjetivas relacionadas con el ejercicio en mujeres ancianas antes y después de la actividad física en ambientes real y virtual, así como la preferencia por el ambiente. La muestra consistió en 20 mujeres ancianas (71,1 ± 6,5 años) que ejecutaran sesiones de danza en ambos ambientes y responderán al instrumento Subjective Exercise Experiences Scale (SEES) antes y después de la práctica. En la situación virtual fue empleado el juego Just Dance I de la consola Nintendo® Wii. En la situación real, cada participante reprodujo los mismos movimientos presentados por el investigador. Para el análisis de los datos de la SEES se utilizó las pruebas de Wilcoxon y Mann-Whitney (p <0,05). Hubo reducción significativa en la puntuación de la subescala distress psicológico de la SEES después de ambas las situaciones experimentales y aumento del bienestar positivo sólo en el ambiente virtual. La mayoría de las mujeres eligieron el ambiente real como el favorito.