Here I'll point out an open access paper on Wnt signaling in aging. The full paper is PDF format only at the present time. The Wnt signaling pathway plays a range of important roles in embryonic development, cancer, and regeneration. It also changes over the course of aging, one of countless specific reactions to accumulated cell and tissue damage, and these changes are thought to be a part of the characteristic decline in stem cell activity that takes place in later life. Less stem cell activity means less tissue maintenance and the gradual failure of organ function and integrity. There is considerable interest in the scientific community in finding ways to restore tissue maintenance, but most of those involved do not address the underlying damage that causes aging, instead seeking to override some of the reactions to that damage.
Here, however, researchers are looking at the merits of exercise in the context of Wnt signaling and tissue maintenance in old age. There is ample evidence to show that regular exercise is beneficial for even extremely old individuals, and its effects on Wnt signaling may be one of the reasons why this is the case:
Aging is an inevitable physiological process that leads to the dysfunction of various tissues, and these changes may contribute to certain diseases, and ultimately death. Recent research has discovered biological pathways that promote aging. This review focuses on Wnt signaling, Wnt is a highly conserved secreted signaling molecule that plays an essential role in the development and function of various tissues, and is a notable factor that regulates aging. Although Wnt signaling influences aging in various tissues, its effects are particularly prominent in neuronal tissue and skeletal muscle. In neuronal tissue, neurogenesis is attenuated by the downregulation of Wnt signaling with aging. Skeletal muscle can also become weaker with aging, in a process known as sarcopenia. A notable cause of sarcopenia is the myogenic-to-fibrogenic transdifferentiation of satellite cells by excessive upregulation of Wnt signaling with aging, resulting in the impaired regenerative capacity of aged skeletal muscle.
However, exercise is very useful for preventing the age-related alterations in neuronal tissue and skeletal muscle. Upregulation of Wnt signaling is implicated in the positive effects of exercise, resulting in the activation of neurogenesis in adult neuronal tissue and myogenesis in mature skeletal muscle. Although more investigations are required to thoroughly understand age-related changes and their biological mechanisms in a variety of tissues, this review proposes exercise as a useful therapy for the elderly, to prevent the negative effects of aging and maintain their quality of life.