Effects of PGC-1α overexpression on the myogenic response during skeletal muscle regeneration.

The ability of skeletal muscle to regenerate from injury is crucial for locomotion, metabolic health, and quality of life. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1A) is a transcriptional coactivator required for mitochondrial biogenesis. Increased mitochondrial biogenesis is associated with improved muscle cell differentiation, however PGC1A's role in skeletal muscle regeneration following damage requires further investigation. The purpose of this study was to investigate the role of skeletal muscle-specific PGC1A overexpression during regeneration following damage. 22 C57BL/6J (WT) and 26 PGC1A muscle transgenic (A1) mice were injected with either phosphate-buffered saline (PBS, uninjured control) or Bupivacaine (MAR, injured) into their tibialis anterior (TA) muscle to induce skeletal muscle damage. TA muscles were extracted 3- or 28-days post-injury and analyzed for markers of regenerative myogenesis and protein turnover. Pgc1a mRNA was ∼10-20 fold greater in A1 mice. Markers of protein synthesis, AKT and 4EBP1, displayed decreases in A1 mice compared to WT at both timepoints indicating a decreased protein synthetic response. Myod mRNA was ∼75% lower compared to WT 3 days post-injection. WT mice exhibited decreased cross-sectional area of the TA muscle at 28 days post-injection with bupivacaine compared to all other groups. PGC1A overexpression modifies the myogenic response during regeneration.

What about trauma? Accounting for trauma exposure and symptoms in the risk of suicide among adolescents who have been adopted.

BACKGROUND: Research suggests that individuals who have been adopted are at increased risk for suicidal behaviors, but this research does not account for the role of trauma. OBJECTIVES: The study provided rates of trauma exposure among individuals who were adopted with child welfare involvement. The study also examined risk of suicidal ideation (SI) and behaviors (SB) based on adoption status, first as bivariate associations and then in context of trauma exposure and symptoms. PARTICIPANTS AND SETTING: Participants in the LONGSCAN study were recruited at multiple US sites based on various risk factors for maltreatment. The current study included only those individuals with adequate information at key timepoints (n = 894), 106 (11.9%) of whom were adopted. METHODS: Measures were collected at multiple timepoints, including caregiver-report, self-report, and review of child welfare records. Data were analyzed through logistic regression and descriptive statistics. RESULTS: High rates of potentially traumatic experiences were found among individuals who were adopted (over 93%). The bivariate logistic regression replicated previous findings that adolescents who were adopted had increased likelihood of endorsing SI (OR 2.14, 95% CI 1.27-3.60, p = .004) and SB (OR 2.40, 95% CI 1.24-4.63, p = .009) compared to non-adopted peers. However, when polytrauma and traumatic stress symptoms were added to the model, adoption was no longer a significant predictor for SI (OR 1.35, 95% CI 0.70-2.60, p = .369) or SB (OR 1.46, 95% CI 0.68-3.13, p = .332). CONCLUSIONS: Although much remains to be explored about the association between adoption and risk for suicidal thoughts and behaviors, the current study indicates that traumatic stress plays a critical role.

Perinatal anxiety and depressive symptoms and perception of child behavior and temperament in early motherhood.

The perinatal period is a vulnerable time for the development of psychopathology, particularly mood and anxiety disorders. In the study of maternal anxiety, important questions remain regarding the association between maternal anxiety symptoms and subsequent child outcomes. This study examined the association between depressive and anxiety symptoms, namely social anxiety, panic, and agoraphobia disorder symptoms during the perinatal period and maternal perception of child behavior, specifically different facets of development and temperament. Participants (N = 104) were recruited during pregnancy from a community sample. Participants completed clinician-administered and self-report measures of depressive and anxiety symptoms during the third trimester of pregnancy and at 16 months postpartum; child behavior and temperament outcomes were assessed at 16 months postpartum. Child development areas included gross and fine motor skills, language and problem-solving abilities, and personal/social skills. Child temperament domains included surgency, negative affectivity, and effortful control. Hierarchical multiple regression analyses demonstrated that elevated prenatal social anxiety symptoms significantly predicted more negative maternal report of child behavior across most measured domains. Elevated prenatal social anxiety and panic symptoms predicted more negative maternal report of child effortful control. Depressive and agoraphobia symptoms were not significant predictors of child outcomes. Elevated anxiety symptoms appear to have a distinct association with maternal report of child development and temperament. Considering the relative influence of anxiety symptoms, particularly social anxiety, on maternal report of child behavior and temperament can help to identify potential difficulties early on in mother-child interactions as well as inform interventions for women and their families.