Narciclasine attenuates diet-induced obesity by promoting oxidative metabolism in skeletal muscle.

Obesity develops when caloric intake exceeds metabolic needs. Promoting energy expenditure represents an attractive approach in the prevention of this fast-spreading epidemic. Here, we report a novel pharmacological strategy in which a natural compound, narciclasine (ncls), attenuates diet-induced obesity (DIO) in mice by promoting energy expenditure. Moreover, ncls promotes fat clearance from peripheral metabolic tissues, improves blood metabolic parameters in DIO mice, and protects these mice from the loss of voluntary physical activity. Further investigation suggested that ncls achieves these beneficial effects by promoting a shift from glycolytic to oxidative muscle fibers in the DIO mice thereby enhancing mitochondrial respiration and fatty acid oxidation (FAO) in the skeletal muscle. Moreover, ncls strongly activates AMPK signaling specifically in the skeletal muscle. The beneficial effects of ncls treatment in fat clearance and AMPK activation were faithfully reproduced in vitro in cultured murine and human primary myotubes. Mechanistically, ncls increases cellular cAMP concentration and ADP/ATP ratio, which further lead to the activation of AMPK signaling. Blocking AMPK signaling through a specific inhibitor significantly reduces FAO in myotubes. Finally, ncls also enhances mitochondrial membrane potential and reduces the formation of reactive oxygen species in cultured myotubes.

Inactivation of PPARß/δ adversely affects satellite cells and reduces postnatal myogenesis.

Peroxisome proliferator-activated receptor ß/δ (PPARß/δ) is a ubiquitously expressed gene with higher levels observed in skeletal muscle. Recently, our laboratory showed (Bonala S, Lokireddy S, Arigela H, Teng S, Wahli W, Sharma M, McFarlane C, Kambadur R. J Biol Chem 287: 12935-12951, 2012) that PPARß/δ modulates myostatin activity to induce myogenesis in skeletal muscle. In the present study, we show that PPARß/δ-null mice display reduced body weight, skeletal muscle weight, and myofiber atrophy during postnatal development. In addition, a significant reduction in satellite cell number was observed in PPARß/δ-null mice, suggesting a role for PPARß/δ in muscle regeneration. To investigate this, tibialis anterior muscles were injured with notexin, and muscle regeneration was monitored on days 3, 5, 7, and 28 postinjury. Immunohistochemical analysis revealed an increased inflammatory response and reduced myoblast proliferation in regenerating muscle from PPARß/δ-null mice. Histological analysis confirmed that the regenerated muscle fibers of PPARß/δ-null mice maintained an atrophy phenotype with reduced numbers of centrally placed nuclei. Even though satellite cell numbers were reduced before injury, satellite cell self-renewal was found to be unaffected in PPARß/δ-null mice after regeneration. Previously, our laboratory had showed (Bonala S, Lokireddy S, Arigela H, Teng S, Wahli W, Sharma M, McFarlane C, Kambadur R. J Biol Chem 287: 12935-12951, 2012) that inactivation of PPARß/δ increases myostatin signaling and inhibits myogenesis. Our results here indeed confirm that inactivation of myostatin signaling rescues the atrophy phenotype and improves muscle fiber cross-sectional area in both uninjured and regenerated tibialis anterior muscle from PPARß/δ-null mice. Taken together, these data suggest that absence of PPARß/δ leads to loss of satellite cells, impaired skeletal muscle regeneration, and postnatal myogenesis. Furthermore, our results also demonstrate that functional antagonism of myostatin has utility in rescuing these effects.

Intergenerational transmission of risk for social inhibition: the interplay between parental responsiveness and genetic influences.

To better understand mechanisms underlying the intergenerational transmission of social anxiety, we used a prospective adoption design to examine the roles of genetic influences (inferred from birth mothers' social phobia) and rearing environment (adoptive mothers' and fathers' responsiveness) on the development of socially inhibited, anxious behaviors in children between 18 and 27 months of age. The sample consisted of 275 adoption-linked families, each including an adopted child, adoptive parents, and a birth mother. Results indicated that children whose birth mothers met criteria for the diagnosis of social phobia showed elevated levels of observed behavioral inhibition in a social situation at 27 months of age if their adoptive mothers provided less emotionally and verbally responsive rearing environments at 18 months of age. Conversely, in the context of higher levels of maternal responsiveness, children of birth mothers with a history of social phobia did not show elevated levels of behavioral inhibition. These findings on maternal responsiveness were replicated in a model predicting parent reports of child social anxiety. The findings are discussed in terms of gene-environment interactions in the intergenerational transmission of social anxiety.

The Beijing Twin Study (BeTwiSt): a longitudinal study of child and adolescent development.

Rates of emotional and behavioral problems among children and adolescents in China are increasing and represent a major public health concern. To investigate the etiology of such problems, including the effects and interplay of genes and environment, the Beijing Twin Study (BeTwiSt) was established. A representative sample of adolescent twins in Beijing (N = 1,387 pairs of adolescent twins, mostly between the ages of 10 and 18 years) was recruited and assessed longitudinally. Data collection included the following: emotional and behavioral problems (e.g., depressive symptoms, anxiety, delinquency, drinking, and smoking); family, peer, and school environments; stress; social and academic competence; cognitive traits (e.g., emotion suppression, rumination, and effortful control); and saliva samples for DNA genotyping and sequencing. The combination of quantitative and molecular genetic approaches and the timeliness of the project, with the sample residing in a region with a rapidly changing economic and cultural climate, are particular strengths of this study. Findings from this study are expected to help understanding of the etiological mechanisms underlying child and adolescent normal and abnormal development in regions undergoing substantial social, cultural, and economic changes.

Lack of Smad3 signaling leads to impaired skeletal muscle regeneration.

Smad3 is a key intracellular signaling mediator for both transforming growth factor-ß and myostatin, two major regulators of skeletal muscle growth. Previous published work has revealed pronounced muscle atrophy together with impaired satellite cell functionality in Smad3-null muscles. In the present study, we have further validated a role for Smad3 signaling in skeletal muscle regeneration. Here, we show that Smad3-null mice had incomplete recovery of muscle weight and myofiber size after muscle injury. Histological/immunohistochemical analysis suggested impaired inflammatory response and reduced number of activated myoblasts during the early stages of muscle regeneration in the tibialis anterior muscle of Smad3-null mice. Nascent myofibers formed after muscle injury were also reduced in number. Moreover, Smad3-null regenerated muscle had decreased oxidative enzyme activity and impaired mitochondrial biogenesis, evident by the downregulation of the gene encoding mitochondrial transcription factor A, a master regulator of mitochondrial biogenesis. Consistent with known Smad3 function, reduced fibrotic tissue formation was also seen in regenerated Smad3-null muscle. In conclusion, Smad3 deficiency leads to impaired muscle regeneration, which underscores an essential role of Smad3 in postnatal myogenesis. Given the negative role of myostatin during muscle regeneration, the increased expression of myostatin observed in Smad3-null muscle may contribute to the regeneration defects.

Negative emotionality and externalizing problems in toddlerhood: overreactive parenting as a moderator of genetic influences.

The current study examines the interplay between parental overreactivity and children's genetic backgrounds as inferred from birth parent characteristics on the development of negative emotionality during infancy, and in turn, to individual differences in externalizing problems in toddlerhood. The sample included 361 families linked through adoption (birth parents and adoptive families). Data were collected when the children were 9, 18, and 27 months old. Results indicated links between individual levels and changes in negative emotionality during infancy and toddlerhood to externalizing problems early in the third year of life. Findings also revealed an interaction between birth mother negative affect and adoptive mother overreactive parenting on children's negative emotionality. This Genotype × Environment interaction predicted externalizing problems indirectly through its association with negative emotionality and revealed stronger effects of genetic risk for children with less overreactive parenting from their mothers. Limitations of this study and directions for future research are discussed.

Trajectories of parenting and child negative emotionality during infancy and toddlerhood: a longitudinal analysis.

The current longitudinal study examined trajectories of child negative emotionality, parenting efficacy, and overreactive parenting among 382 adoptive families during infancy and toddlerhood. Data were collected from adoptive parents when the children were 9-, 18-, and 27-month-old. Latent growth curve modeling indicated age-related increases in child negative emotionality and overreactive parenting for adoptive fathers and adoptive mothers (AM), and decreases in parent efficacy among AM. Increases in child negative emotionality were also associated with increases in parent overreactivity and decreases in maternal efficacy. Mothers' and fathers' developmental patterns were linked within but not across parenting domains. Limitations and directions for future research are discussed.

Paraneoplastic Secretion of Multiple Phosphatonins From a Deep Fibrous Histiocytoma Causing Oncogenic Osteomalacia.

CONTEXT: Literature suggests that oncogenic osteomalacia is usually caused by a benign mesenchymal tumor secreting fibroblast growth factor subtype-23 (FGF-23), but the involvement of other phosphatonins has only been scarcely reported. We have previously published a seemingly typical case of oncogenic osteomalacia. Following curative neoplasm resection, we now report unique molecular characteristics and biology of this tumor. CASE DESCRIPTION: A 25-year-old man had been diagnosed with severe oncogenic osteomalacia that gradually crippled him over 6 years. 68Ga-DOTA-TATE positron emission tomography/computed tomography scan localized the culprit tumor to his left sole, which on resection revealed a deep fibrous histiocytoma displaying a proliferation of spindle cells with storiform pattern associated with multinucleated giant cells resembling osteoclasts. Circulating FGF-23, which was elevated more than 2-fold, declined to undetectable levels 24 h after surgery. Microarray analysis revealed increased tumor gene expression of the phosphatonins FGF-23, matrix extracellular phosphoglycoprotein (MEPE) and secreted frizzled-related protein subtype 4, with elevated levels of all 3 proteins confirmed through immunoblot analysis. Differential expression of genes involved in bone formation and bone mineralization were further identified. The patient made an astonishing recovery from being wheelchair bound to fully self-ambulant 2 months postoperatively. CONCLUSION: This report describes oncogenic osteomalacia due to a deep fibrous histiocytoma, which coincidentally has been found to induce profound muscle weakness via the overexpression of 3 phosphatonins, which resolved fully upon radical resection of the tumor. Additionally, genes involved in bone formation and bone remodeling contribute to the molecular signature of oncogenic osteomalacia.

Infant pathways to externalizing behavior: evidence of Genotype x Environment interaction.

To further the understanding of the effects of early experiences, 9-month-old infants were observed during a frustration task. The analytical sample was composed of 348 linked triads of participants (adoptive parents, adopted child, and birth parent[s]) from a prospective adoption study. It was hypothesized that genetic risk for externalizing problems and affect dysregulation in the adoptive parents would independently and interactively predict a known precursor to externalizing problems: heightened infant attention to frustrating events. Results supported the moderation hypotheses involving adoptive mother affect dysregulation: Infants at genetic risk showed heightened attention to frustrating events only when the adoptive mother had higher levels of anxious and depressive symptoms. The Genotype x Environment interaction pattern held when substance use during pregnancy was considered.

Influence of parental depressive symptoms on adopted toddler behaviors: an emerging developmental cascade of genetic and environmental effects.

This study examined the developmental cascade of both genetic and environmental influences on toddlers' behavior problems through the longitudinal and multigenerational assessment of psychosocial risk. We used data from the Early Growth and Development Study, a prospective adoption study, to test the intergenerational transmission of risk through the assessment of adoptive mother, adoptive father, and biological parent depressive symptoms on toddler behavior problems. Given that depression is often chronic, we control for across-time continuity and find that in addition to associations between adoptive mother depressive symptoms and toddler externalizing problems, adoptive father depressive symptoms when the child is 9 months of age were associated with toddler problems and associated with maternal depressive symptoms. Findings also indicated that a genetic effect may indirectly influence toddler problems through prenatal pregnancy risk. These findings help to describe how multiple generations are linked through genetic (biological parent), timing (developmental age of the child), and contextual (marital partner) pathways.

Optimization of zygosity determination by questionnaire and DNA genotyping in Chinese adolescent twins.

The main aim of this study was to develop and optimize a questionnaire-based zygosity determination method in Chinese adolescent twins. Participants were 471 pairs of same-sex twins (345 monozygotic, 126 dizygotic) with a mean age of 14.56 years (SD=2.62). A second sample was recruited for cross-validation, including 382 pairs of same-sex twins (261 monozygotic, 121 dizygotic) with a mean age of 12.53 years (SD=2.22). The questionnaire consisted of 12 questions dealing with co-twin similarity or frequency of confusion. Two means were put forward to improve the predictive accuracy of the questionnaire--adding parent-reports to the analysis, and using a 2-point rather than 3-point response format. DNA genotyping was performed on nine short tandem repeat loci, with an estimated zygosity classification accuracy very close to 100%. The validity of all questionnaires was assessed by being compared to the results of DNA analysis. Results of stepwise logistic regression analysis showed that the predictive accuracy of the 3-point self-reported questionnaire is 83.8%. Using parent-reports and 2-point scale led to 3.9% and 4.6% increase in predictive accuracy, respectively. When using the parent-reports and children's self-reports jointly, the predictive accuracy was enhanced to 90.6%. For the cross-validation, the equations and cut-offs derived from the first sample led to an acceptable accuracy (91.3%) in the second sample. In conclusion, the method we developed can be used in future studies among Chinese adolescent twins. Multiple-rater and 2-point response format were suggested for all twin studies for enhancing the predictive accuracy of questionnaires.

Anticancer potential of an exopolysaccharide from Lactobacillus helveticus MB2-1 on human colon cancer HT-29 cells via apoptosis induction.

This study aimed at investigating the anticancer activity of an exopolysaccharide (EPS) isolated from Lactobacillus helveticus MB2-1. The crude EPS from L. helveticus MB2-1 (LHEPS) was fractionated into three fractions, namely LHEPS-1, LHEPS-2 and LHEPS-3. LHEPS-1 exhibited the most effective anti-proliferative activity, which was associated with a stronger inhibition rate and increased lactate dehydrogenase leakage of human colon cancer HT-29 cells. Flow cytometry analysis and colorimetric assay revealed that LHEPS-1 induced cell cycle arrest by preventing G1 to S transition and increased the apoptosis rate. Furthermore, LHEPS-1 enhanced the production of intracellular reactive oxygen species (ROS) and the activity of caspases-8/9/3, increased the levels of pro-apoptotic Bax and mitochondrial cytochrome c, while decreased the anti-apoptotic Bcl-2 level, indicating that LHEPS-1 might induce the apoptosis of HT-29 cells through a ROS-dependent pathway and a mitochondria-dependent pathway. These findings suggest that LHEPS-1 may be developed as an effective food and/or drug for the prevention and therapeutics of cancer, especially human colon cancer.

Left too early: the effects of age at separation from parents on Chinese rural children's symptoms of anxiety and depression.

OBJECTIVES: We examined the effect of age at separation from parents on symptoms of anxiety and depression among children in rural communities in China whose parents migrated to cities in search of employment opportunities during the country's rapid economic development. METHODS: Students in 3 rural areas, Anhui, Chongqing, and Guizhou (N = 592; age = 10-17 years), completed questionnaires that asked about symptoms of state and trait anxiety, as well as depression and age at separation from parents. RESULTS: Children who were separated from parents at a younger age had more symptoms of anxiety and depression. This effect was especially pronounced for children who were separated from their mothers or from both parents. CONCLUSIONS: China's explosive economic growth appears to exact a significant toll on left-behind children's mental health, particularly on children whose parents left early in their lives. The unintended consequences of the economic boom on child development need to be further examined in prospective studies.

The longitudinal effects of stressful life events on adolescent depression are buffered by parent-child closeness.

This study investigated the prospective links of negative life events and parent-child closeness with depressive symptoms among siblings using a multilevel modeling approach with a genetically informative design. The sample consisted of 756 adolescents (378 sibling pairs) who participated in two waves of the Nonshared Environment in Adolescent Development Project. Sibling pairs with varying degree of genetic relatedness (i.e., monozygotic, dizygotic, full siblings, half siblings, and genetically unrelated siblings) were included. The results showed that negative life events, both personal and family life events, and parent-child closeness at Time 1 were significantly associated with depressive symptoms at Time 2 after accounting for the intrapair correlations between siblings. The effects remained significant after controlling for the levels of preexisting depressive symptoms. More importantly, closeness with mothers, but not with fathers, moderated the effects of both personal and family negative life events on subsequent depressive symptoms.

Aggressive behavior between siblings and the development of externalizing problems: evidence from a genetically sensitive study.

This study investigated the prospective links between sibling aggression and the development of externalizing problems using a multilevel modeling approach with a genetically sensitive design. The sample consisted of 780 adolescents (390 sibling pairs) who participated in 2 waves of the Nonshared Environment in Adolescent Development project. Sibling pairs with varying degree of genetic relatedness, including monozygotic twins, dizygotic twins, full siblings, half siblings, and genetically unrelated siblings, were included. The results showed that sibling aggression at Time 1 was significantly associated with the focal child's externalizing problems at Time 2 after accounting for the intraclass correlations between siblings. Sibling aggression remained significant in predicting subsequent externalizing problems even after controlling for the levels of preexisting externalizing problems and mothers' punitive parenting. This pattern of results was fairly robust across models with different informants. The findings provide converging evidence for the unique contribution of sibling aggression in understanding changes in externalizing problems during adolescence.

Early pubertal maturation and internalizing problems in adolescence: sex differences in the role of cortisol reactivity to interpersonal stress.

An accumulating body of literature has shown a link between early pubertal maturation and internalizing problems, particularly among girls. Our knowledge is, however, limited with regard to what accounts for this association. Based on a hypothesis that early maturing girls have heightened stress sensitivity that increases the risk of internalizing problems, the present investigation examined the roles of pubertal timing and salivary cortisol reactivity to interpersonal stressors in adolescents' internalizing problems. Results from 110 boys and 106 girls (ages 11-16) indicated that early maturing adolescents had increased internalizing symptoms. Early maturing girls' higher levels of internalizing problems were at least partially attributed to their heightened sensitivity to interpersonal stress. Finally, girls' cortisol reactivity to interpersonal challenge was more strongly associated with internalizing problems than boys' reactivity.

Emotional and behavioral effects of romantic relationships in Chinese adolescents.

Adolescents' romantic relationships have been associated with higher levels of depression, although their links with externalizing behavioral problems remain unclear. The present study examined the impact of adolescent romantic relationships on depression and externalizing behaviors in a large sample of 10,509 Chinese secondary school students (ages 12-19, 54.5% female). The results showed that romantic involvement in adolescence, especially in early adolescence, was associated with more depressive symptoms and behavior problems. Breakups in romantic relationships were an important factor in producing the negative emotional and behavioral consequences. Romantically involved girls experienced higher levels of depressive symptoms, while romantically involved boys had higher levels of externalizing behaviors, compared to their non-dating peers. The results also indicated that the adverse impact was stronger for those involved in romantic relationships at younger ages.

Bridging the divide: openness in adoption and postadoption psychosocial adjustment among birth and adoptive parents.

Using 323 matched parties of birth mothers and adoptive parents, this study examined the association between the degree of adoption openness (e.g., contact and knowledge between parties) and birth and adoptive parents' postadoption adjustment shortly after the adoption placement (6 to 9 months). Data from birth fathers (N = 112), an understudied sample, were also explored. Openness was assessed by multiple informants. Results indicated that openness was significantly related to satisfaction with adoption process among adoptive parents and birth mothers. Increased openness was positively associated with birth mothers' postplacement adjustment, as indexed by birth mothers' self-reports and the interviewers' impression of birth mothers' adjustment. Birth fathers' report of openness was associated with their greater satisfaction with the adoption process and better postadoption adjustment.

Do intrauterine or genetic influences explain the foetal origins of chronic disease? A novel experimental method for disentangling effects.

BACKGROUND: There is much evidence to suggest that risk for common clinical disorders begins in foetal life. Exposure to environmental risk factors however is often not random. Many commonly used indices of prenatal adversity (e.g. maternal gestational stress, gestational diabetes, smoking in pregnancy) are influenced by maternal genes and genetically influenced maternal behaviour. As mother provides the baby with both genes and prenatal environment, associations between prenatal risk factors and offspring disease maybe attributable to true prenatal risk effects or to the "confounding" effects of genetic liability that are shared by mother and offspring. Cross-fostering designs, including those that involve embryo transfer have proved useful in animal studies. However disentangling these effects in humans poses significant problems for traditional genetic epidemiological research designs. METHODS: We present a novel research strategy aimed at disentangling maternally provided pre-natal environmental and inherited genetic effects. Families of children aged 5 to 9 years born by assisted reproductive technologies, specifically homologous IVF, sperm donation, egg donation, embryo donation and gestational surrogacy were contacted through fertility clinics and mailed a package of questionnaires on health and mental health related risk factors and outcomes. Further data were obtained from antenatal records. RESULTS: To date 741 families from 18 fertility clinics have participated. The degree of association between maternally provided prenatal risk factor and child outcome in the group of families where the woman undergoing pregnancy and offspring are genetically related (homologous IVF, sperm donation) is compared to association in the group where offspring are genetically unrelated to the woman who undergoes the pregnancy (egg donation, embryo donation, surrogacy). These comparisons can be then examined to infer the extent to which prenatal effects are genetically and environmentally mediated. CONCLUSION: A study based on children born by IVF treatment and who differ in genetic relatedness to the woman undergoing the pregnancy is feasible. The present report outlines a novel experimental method that permits disaggregation of maternally provided inherited genetic and post-implantation prenatal effects.

The early growth and development study: a prospective adoption design.

The Early Growth and Development Study is a prospective adoption study of birth parents, adoptive parents, and adopted children (N=359 triads) that was initiated in 2003. The primary study aims are to examine how family processes mediate or moderate the expression of genetic influences in order to aid in the identification of specific family processes that could serve as malleable targets for intervention. Participants in the study are recruited through adoption agencies located throughout the United States, following the birth of a child. Assessments occur at 6-month intervals until the child reaches 3 years of age. Data collection includes the following primary constructs: infant and toddler temperament, social behavior, and health; birth and adoptive parent personality characteristics, psychopathology, competence, stress, and substance use; adoptive parenting and marital relations; and prenatal exposure to drugs and maternal stress. Preliminary analyses suggest the representativeness of the sample and minimal confounding effects of current trends in adoption practices, including openness and selective placement. Future plans are described.