Neurogenic muscle atrophy is the loss of skeletal muscle mass and function that occurs with nerve injury and in denervating diseases such as amyotrophic lateral sclerosis. Aside from prompt restoration of innervation and exercise where feasible, there are currently no effective strategies for maintaining skeletal muscle mass in the setting of denervation. We conducted a longitudinal analysis of gene expression changes occurring in atrophying skeletal muscle, and identified Gadd45a as a gene that shows one of the earliest and most sustained increases in expression in skeletal muscle after denervation. We evaluated the role of this induction using genetic mouse models and found that mice lacking GADD45A show accelerated and exacerbated neurogenic muscle atrophy, as well as loss of fiber type identity. Our genetic analyses demonstrate that, rather than directly contributing to muscle atrophy as proposed in earlier studies, GADD45A induction likely represents a protective negative feedback response to denervation. Establishing the downstream effectors that mediate this protective effect and the pathways they participate in may yield new opportunities to modify the course of muscle atrophy. Brief summaryGADD45A is induced after muscle denervation and provides protective negative feedback response. Strategies to augment this induction may offer therapeutic targets to prevent denervation atrophy.

There has been a global increase in pediatric endocrinology referrals for the concerns of early puberty. The objective of this study was to determine the reasons behind this increase. A retrospective cross-sectional study was designed to analyze the clinical characteristics of patients seen for the concerns of early puberty in pediatric endocrinology clinic of a tertiary care center (Study A). Additionally, a prospective questionnaire study was designed to assess the knowledge and concerns of the mothers regarding the timing of puberty in girls (Study B). In study A, of the 305 girls, 42.9% were overweight/obese, 68.5% either had normal pubertal development for age or were prepubertal, 1 had non-classic congenital adrenal hyperplasia, and 2 had central precocious puberty. Of the 36 boys, 56% were overweight/obese, 64% either had normal pubertal development for age or were prepubertal, and 1 had non-classic congenital adrenal hyperplasia. In study B, 95% of the participants thought the girls have been developing earlier, over 10% considered the first sign of puberty to be normal after the age 14 years and 12.4% considered menarche to be normal after age 14 years. The common sources of anxiety for the participants regarding the earlier timing of puberty were psychosocial issues and short final height. In conclusion, many parents had wrong beliefs/information about the normal timing of puberty and were concerned about precocious puberty in girls. Education of parents about the normal timing of puberty may help avoiding unnecessary referrals, parental anxiety, and financial burden to the society.