Fight Aging! Newsletter, April 24th 2023

In this study, researchers show that mice lacking a functional ATF4 gene show little to no loss of grip strength and treadmill performance into late life; it is quite an impressive effect size. Assessments of muscle biochemistry do show age-related declines, but to a lesser degree than the controls. How ATF4 knockout functions to produce this outcome is an interesting question. The researchers point out a range of possible downstream and upstream targets that have been implicated in the regulation of muscle growth, but it will clearly require further work to identify the important mechanisms involved. Aging slowly erodes skeletal muscle strength and mass, eventually leading to profound functional deficits and muscle atrophy. The molecular mechanisms of skeletal muscle aging are not well understood. To better understand mechanisms of muscle aging, we investigated the potential role of ATF4, a transcription regulatory protein that can rapidly promote skeletal muscle atrophy in young animals deprived of adequate nutrition or activity. To test the hypothesis that ATF4 may be involved in skeletal muscle aging, we studied fed and active muscle-specific ATF4 knockout mice (ATF4 mKO mice) at 6 months of age, when wild-type mice have achieved peak muscle mass and function, and at 22 months of age, when wild-type mice have begun to manifest age-related muscle atrophy and weakness. We found that 6-month-old ATF4 mKO mice develop normally and are phenotypically indistingu...
Source: Fight Aging! - Category: Research Authors: Tags: Newsletters Source Type: blogs