Age- and stress-associated C. elegans granulins impair lysosomal function and induce a compensatory HLH-30/TFEB transcriptional response.

The progressive failure of protein homeostasis is a hallmark of aging and a common feature in neurodegenerative disease. As the enzymes executing the final stages of autophagy, lysosomal proteases are key contributors to the maintenance of protein homeostasis with age. We previously reported that expression of granulin peptides, the cleavage products of the neurodegenerative disease protein progranulin, enhance the accumulation and toxicity of TAR DNA binding protein 43 (TDP-43) in Caenorhabditis elegans (C. elegans). In this study we show that C. elegans granulins are produced in an age- and stress-dependent manner. Granulins localize to the endolysosomal compartment where they impair lysosomal protease expression and activity. Consequently, protein homeostasis is disrupted, promoting the nuclear translocation of the lysosomal transcription factor HLH-30/TFEB, and prompting cells to activate a compensatory transcriptional program. The three C. elegans granulin peptides exhibited distinct but overlapping functional effects in our assays, which may be due to amino acid composition that results in distinct electrostatic and hydrophobicity profiles. Our results support a model in which granulin production modulates a critical transition between the normal, physiological regulation of protease activity and the impairment of lysosomal function that can occur with age and disease.

The Outcome of the Cryptococcus neoformans-Macrophage Interaction Depends on Phagolysosomal Membrane Integrity.

Cryptococcus neoformans is a fungal pathogen with worldwide distribution. C. neoformans resides within mature phagolysosomes where it often evades killing and replicates. C. neoformans induces phagolysosomal membrane permeabilization (PMP), but the mechanism for this phenomenon and its consequences for macrophage viability are unknown. In this study, we used flow cytometry methodology in combination with cell viability markers and LysoTracker to measure PMP in J774.16 and murine bone marrow-derived macrophages infected with C. neoformans Our results showed that cells manifesting PMP were positive for apoptotic markers, indicating an association between PMP and apoptosis. We investigated the role of phospholipase B1 in C. neoformans induction of PMP. Macrophages infected with a C. neoformans Δplb1 mutant had reduced PMP compared with those infected with wild-type and phospholipase B1-complemented strains, suggesting a mechanism of action for this virulence factor. Capsular enlargement inside macrophages was identified as an additional likely mechanism for phagolysosomal membrane damage. Macrophages undergoing apoptosis did not maintain an acidic phagolysosomal pH. Induction of PMP with ciprofloxacin enhanced macrophages to trigger lytic exocytosis whereas nonlytic exocytosis was common in those without PMP. Our results suggest that modulation of PMP is a critical event in determining the outcome of C. neoformans-macrophage interaction.

OPREVENT2: Design of a multi-institutional intervention for obesity control and prevention for American Indian adults.

BACKGROUND: Obesity and other nutrition-related chronic disease rates are high in American Indian (AI) populations, and an urgent need exists to identify evidence-based strategies for prevention and treatment. Multi-level, multi-component (MLMC) interventions are needed, but there are significant knowledge gaps on how to deliver these types of interventions in low-income rural AI communities. METHODS: OPREVENT2 is a MLMC intervention targeting AI adults living in six rural reservations in New Mexico and Wisconsin. Aiming to prevent and reduce obesity in adults by working at multiple levels of the food and physical activity (PA) environments, OPREVENT2 focuses on evidence-based strategies known to increase access to, demand for, and consumption of healthier foods and beverages, and increase worksite and home-based opportunities for PA. OPREVENT2 works to create systems-level change by partnering with tribal stakeholders, multiple levels of the food and PA environment (food stores, worksites, schools), and the social environment (children as change agents, families, social media). Extensive evaluation will be conducted at each level of the intervention to assess effectiveness via process and impact measures. DISCUSSION: Novel aspects of OPREVENT2 include: active engagement with stakeholders at many levels (policy, institutional, and at multiple levels of the food and PA system); use of community-based strategies to engage policymakers and other key stakeholders (community workshops, action committees); emphasis on both the built environment (intervening with retail food sources) and the social environment. This paper describes the design of the intervention and the evaluation plan of the OPREVENT2. TRIAL REGISTRATION: Clinical Trial Registration: NCT02803853 (June 10, 2016).

Heritability of Children's Dietary Intakes: A Population-Based Twin Study in China.

BACKGROUND: Despite evidence for some genetic control of dietary intake in adults, there is little evidence of how genetic factors influence children's dietary patterns. OBJECTIVE: To estimate heritability of dietary intake in twin children from China and test if genetic effects on dietary intakes vary by the children's socio-economic status (SES). METHODS: A sample of 622 twins (162 monozygotic and 149 dizygotic pairs; 298 boys and 324 girls aged 7-15 years) was recruited in South China. Dietary intakes were assessed using a validated 145-item semi-quantitative food frequency questionnaire. Pooled and sex-specific dietary patterns were identified using factor analysis. Heritability was estimated using structural equation models. RESULTS: Heritable components differed by gender and for nutrients and food groups; and estimated heritability of dietary patterns was generally greater in girls than boys. In boys, estimated heritabilities ranged from 18.8% (zinc) to 58.4% (fat) for nutrients; and for food group, 1.1% (Western fast foods) to 65.8% (soft drinks). In girls, these estimates ranged from 5.1% (total energy) to 38.7% (percentage of energy from fat) for nutrients, and 12.6% (eggs) to 94.6% (Western fast foods) for food groups. Factor analysis identified five food patterns: vegetables and fruits, fried and fast foods, beverages, snacks and meats. Maternal education and family income were positively associated with higher heritabilities for intake of meat, fried, and fast food. CONCLUSIONS: Genetic influence on dietary intakes differed by gender, nutrients, food groups, and dietary patterns among Chinese twins. Parental SES characteristics modified the estimated genetic influence.

BAX inhibitor-1 regulates autophagy by controlling the IRE1α branch of the unfolded protein response.

Both autophagy and apoptosis are tightly regulated processes playing a central role in tissue homeostasis. Bax inhibitor 1 (BI-1) is a highly conserved protein with a dual role in apoptosis and endoplasmic reticulum (ER) stress signalling through the regulation of the ER stress sensor inositol requiring kinase 1 α (IRE1α). Here, we describe a novel function of BI-1 in the modulation of autophagy. BI-1-deficient cells presented a faster and stronger induction of autophagy, increasing LC3 flux and autophagosome formation. These effects were associated with enhanced cell survival under nutrient deprivation. Repression of autophagy by BI-1 was dependent on cJun-N terminal kinase (JNK) and IRE1α expression, possibly due to a displacement of TNF-receptor associated factor-2 (TRAF2) from IRE1α. Targeting BI-1 expression in flies altered autophagy fluxes and salivary gland degradation. BI-1 deficiency increased flies survival under fasting conditions. Increased expression of autophagy indicators was observed in the liver and kidney of bi-1-deficient mice. In summary, we identify a novel function of BI-1 in multicellular organisms, and suggest a critical role of BI-1 as a stress integrator that modulates autophagy levels and other interconnected homeostatic processes.

Validation of a BMI cut-off point to predict an adverse cardiometabolic profile with adiposity measurements by dual-energy X-ray absorptiometry in Guatemalan children.

OBJECTIVE: To identify a body fat percentage (%BF) threshold related to an adverse cardiometabolic profile and its surrogate BMI cut-off point. DESIGN: Cross-sectional study. SETTING: Two public schools in poor urban areas on the outskirts of Guatemala City. SUBJECTS: A convenience sample of ninety-three healthy, prepubertal, Ladino children (aged 7-12 years). RESULTS: Spearman correlations of cardiometabolic parameters were higher with %BF than with BMI-for-age Z-score. BMI-for-age Z-score and %BF were highly correlated (r=0·84). The %BF threshold that maximized sensitivity and specificity for predicting an adverse cardiometabolic profile (elevated homeostasis model assessment-insulin resistance index and/or total cholesterol:HDL-cholesterol ratio) according to receiver operating characteristic curve analysis was 36 %. The BMI-for-age Z-score cut-off point that maximized the prediction of BF ≥ 36 % by the same procedure was 1·5. The area under the curve (AUC) for %BF and for BMI data showed excellent accuracy to predict an adverse cardiometabolic profile (AUC 0·93 (sd 0·04)) and excess adiposity (AUC 0·95 (sd 0·02)). CONCLUSIONS: Since BMI standards have limitations in screening for adiposity, specific cut-off points based on ethnic-/sex- and age-specific %BF thresholds are needed to better predict an adverse cardiometabolic profile.

Targeting the UPR transcription factor XBP1 protects against Huntington's disease through the regulation of FoxO1 and autophagy.

Mutations leading to expansion of a poly-glutamine track in Huntingtin (Htt) cause Huntington's disease (HD). Signs of endoplasmic reticulum (ER) stress have been recently reported in animal models of HD, associated with the activation of the unfolded protein response (UPR). Here we have investigated the functional contribution of ER stress to HD by targeting the expression of two main UPR transcription factors, XBP1 and ATF4 (activating transcription factor 4), in full-length mutant Huntingtin (mHtt) transgenic mice. XBP1-deficient mice were more resistant to developing disease features, associated with improved neuronal survival and motor performance, and a drastic decrease in mHtt levels. The protective effects of XBP1 deficiency were associated with enhanced macroautophagy in both cellular and animal models of HD. In contrast, ATF4 deficiency did not alter mHtt levels. Although, XBP1 mRNA splicing was observed in the striatum of HD transgenic brains, no changes in the levels of classical ER stress markers were detected in symptomatic animals. At the mechanistic level, we observed that XBP1 deficiency led to augmented expression of Forkhead box O1 (FoxO1), a key transcription factor regulating autophagy in neurons. In agreement with this finding, ectopic expression of FoxO1 enhanced autophagy and mHtt clearance in vitro. Our results provide strong evidence supporting an involvement of XBP1 in HD pathogenesis probably due to an ER stress-independent mechanism involving the control of FoxO1 and autophagy levels.

Formative research to develop a community-based intervention for chronic disease prevention in Guatemalan school-age children.

BACKGROUND: Noncommunicable diseases (NCD) are the most common causes of morbidity and mortality worldwide, even in low- and middle-income countries (LMIC). Recent trends in health promotion emphasize community-based interventions as an important strategy for improving health outcomes. The aim of this study was to conduct formative research regarding the perceptions of NCD risk factors, their influencing factors, and community resources available to aid the development and implementation of a community-based intervention with school-age children. METHODS: Focus group discussions (n = 18), home visits (n = 30), and individual semi-structured interviews (n = 26) were conducted in three urban communities in Guatemala with school-age children (10-12 years of age), teachers, parents, and local community members (i.e., school principals, school food kiosk vendors, religious leaders, authority representatives). All focus groups and interviews were transcribed verbatim for thematic analysis. RESULTS: Children, parents, and teachers have general knowledge about modifiable risk factors. Adults worried more about tobacco use, as compared to unhealthy diet and physical inactivity in children. Participants identified features at the intrapersonal (e.g., negative emotional state), interpersonal (e.g., peers as role models), and organizational and community levels (e.g., high levels of crime) that influence these risk factors in children. School committees, religious leaders, and government programs and activities were among the positive community resources identified. CONCLUSIONS: These findings should help researchers in Guatemala and similar LMIC to develop community-based interventions for NCD prevention in school-age children that are effective, feasible, and culturally acceptable.

Assessing dietary intake among infants and toddlers 0-24 months of age in Baltimore, Maryland, USA.

OBJECTIVE: To characterize food and nutrient intake and develop a population-specific food list to be used as a comprehensive dietary assessment tool for Baltimore infants and toddlers aged 0-24 months. The data were used to inform the Growing Leaps and Bounds (GLB) program, which promotes early obesity prevention among Baltimore infants and toddlers. RESEARCH METHODS & PROCEDURES: A cross-sectional dietary survey using 24-hour recalls among randomly selected primary caregivers of infants and toddlers was conducted. RESULTS: Data were collected from 84 children, (response rate 61%) 45 boys; 39 girls. Mean daily energy intakes were 677 kcal, 988 kcal, and 1,123 kcal for children 0-6 months, 7-12 months and 13-24 months, respectively. Infants 0-6 months had higher percentage of energy from fat (48%) than infants 7-12 months (34%) and 13-24 months (31%). Mean daily intakes for all nutrients among 0-12 months old were ≥ Dietary Reference Intakes (DRI), while toddlers 13-24 months had inadequate vitamins A, D, and E intake. Breastfeeding occurred in 33% of infants and toddlers 0 to 6 months, while less than 3% of those aged 7 to 24 months were breastfed. A 104-item food list with eight food and drink categories was developed. CONCLUSIONS: Infants were formula fed with a higher frequency than they were breastfed. The consumption of high-sugar and high-fat foods (e.g. sweetened drinks, French fries) increased with each age group, which can increase the risk of childhood obesity.

External validation of a prediction model for estimating fat mass in children and adolescents in 19 countries: individual participant data meta-analysis.

OBJECTIVE: To evaluate the performance of a UK based prediction model for estimating fat-free mass (and indirectly fat mass) in children and adolescents in non-UK settings. DESIGN: Individual participant data meta-analysis. SETTING: 19 countries. PARTICIPANTS: 5693 children and adolescents (49.7% boys) aged 4 to 15 years with complete data on the predictors included in the UK based model (weight, height, age, sex, and ethnicity) and on the independently assessed outcome measure (fat-free mass determined by deuterium dilution assessment). MAIN OUTCOME MEASURES: The outcome of the UK based prediction model was natural log transformed fat-free mass (lnFFM). Predictive performance statistics of R2, calibration slope, calibration-in-the-large, and root mean square error were assessed in each of the 19 countries and then pooled through random effects meta-analysis. Calibration plots were also derived for each country, including flexible calibration curves. RESULTS: The model showed good predictive ability in non-UK populations of children and adolescents, providing R2 values of >75% in all countries and >90% in 11 of the 19 countries, and with good calibration (ie, agreement) of observed and predicted values. Root mean square error values (on fat-free mass scale) were <4 kg in 17 of the 19 settings. Pooled values (95% confidence intervals) of R2, calibration slope, and calibration-in-the-large were 88.7% (85.9% to 91.4%), 0.98 (0.97 to 1.00), and 0.01 (-0.02 to 0.04), respectively. Heterogeneity was evident in the R2 and calibration-in-the-large values across settings, but not in the calibration slope. Model performance did not vary markedly between boys and girls, age, ethnicity, and national income groups. To further improve the accuracy of the predictions, the model equation was recalibrated for the intercept in each setting so that country specific equations are available for future use. CONCLUSION: The UK based prediction model, which is based on readily available measures, provides predictions of childhood fat-free mass, and hence fat mass, in a range of non-UK settings that explain a large proportion of the variability in observed fat-free mass, and exhibit good calibration performance, especially after recalibration of the intercept for each population. The model demonstrates good generalisability in both low-middle income and high income populations of healthy children and adolescents aged 4-15 years.

Reducing consumption of sugar-sweetened beverages is associated with reduced blood pressure: a prospective study among United States adults.

BACKGROUND: Increased consumption of sugar-sweetened beverages (SSBs) has been associated with an elevated risk of obesity, metabolic syndrome, and type II diabetes mellitus. However, the effects of SSB consumption on blood pressure (BP) are uncertain. The objective of this study was to determine the relationship between changes in SSB consumption and changes in BP among adults. METHODS AND RESULTS: This was a prospective analysis of 810 adults who participated in the PREMIER Study (an 18-month behavioral intervention trial). BP and dietary intake (by two 24-hour recalls) were measured at baseline and at 6 and 18 months. Mixed-effects models were applied to estimate the changes in BP in responding to changes in SSB consumption. At baseline, mean SSB intake was 0.9+/-1.0 servings per day (10.5+/-11.9 fl oz/d), and mean systolic BP/diastolic BP was 134.9+/-9.6/84.8+/-4.2 mm Hg. After potential confounders were controlled for, a reduction in SSB of 1 serving per day was associated with a 1.8-mm Hg (95% confidence interval, 1.2 to 2.4) reduction in systolic BP and 1.1-mm Hg (95% confidence interval, 0.7 to 1.4) reduction in diastolic BP over 18 months. After additional adjustment for weight change over the same period, a reduction in SSB intake was still significantly associated with reductions in systolic and diastolic BPs (P<0.05). Reduced intake of sugars was also significantly associated with reduced BP. No association was found for diet beverage consumption or caffeine intake and BP. These findings suggest that sugars may be the nutrients that contribute to the observed association between SSB and BP. CONCLUSIONS: Reduced consumption of SSB and sugars was significantly associated with reduced BP. Reducing SSB and sugar consumption may be an important dietary strategy to lower BP. CLINICAL TRIAL REGISTRATION: URL: http://clinicaltrials.gov. Unique identifier: NCT00000616.

Lack of activation of the unfolded protein response in mouse and cellular models of Niemann-Pick type C disease.

BACKGROUND: Niemann-Pick type C (NPC) disease is a fatal lysosomal storage disease related to progressive neurodegeneration secondary to abnormal intracellular accumulation of cholesterol. Signs of endoplasmic reticulum (ER) stress have been reported in other lipidoses. Adaptation to ER stress is mediated by the unfolded protein response (UPR), an integrated signal transduction pathway that attenuates stress or triggers apoptosis of irreversibly damaged cells. OBJECTIVE: To investigate the possible engagement of ER stress responses in NPC models. METHODS: We used NPC1 deficient mice and an NPC cell-based model by knocking down the expression of NPC1 to measure several UPR markers through different approaches. RESULTS: Despite expectations that the UPR will be activated in NPC, our results indicate a lack of ER stress reactions in the cerebellum of symptomatic mice. Similarly, knocking down NPC1 in Neuro2a cells leads to clear cholesterol accumulation without evidence of UPR activation. CONCLUSION: Our results suggest that cholesterol overload and neuronal dysfunction in NPC is not associated with ER stress, which contrasts with recent reports suggesting the activation of the UPR in other lysosomal storage diseases.

Acetylated tau inhibits chaperone-mediated autophagy and promotes tau pathology propagation in mice.

Disrupted homeostasis of the microtubule binding protein tau is a shared feature of a set of neurodegenerative disorders known as tauopathies. Acetylation of soluble tau is an early pathological event in neurodegeneration. In this work, we find that a large fraction of neuronal tau is degraded by chaperone-mediated autophagy (CMA) whereas, upon acetylation, tau is preferentially degraded by macroautophagy and endosomal microautophagy. Rerouting of acetylated tau to these other autophagic pathways originates, in part, from the inhibitory effect that acetylated tau exerts on CMA and results in its extracellular release. In fact, experimental blockage of CMA enhances cell-to-cell propagation of pathogenic tau in a mouse model of tauopathy. Furthermore, analysis of lysosomes isolated from brains of patients with tauopathies demonstrates similar molecular mechanisms leading to CMA dysfunction. This study reveals that CMA failure in tauopathy brains alters tau homeostasis and could contribute to aggravate disease progression.

The modifying effect of social class on the relationship between body mass index and breast cancer incidence.

OBJECTIVES: We sought to determine whether social class modifies the effect of BMI on breast cancer incidence. METHODS: Participants included 5642 postmenopausal White women recruited in 1989 to CLUE II, a prospective cohort study in Washington County, Maryland. We obtained exposure data from CLUE II and the 1990 US Census. We used survival and random-effects Cox proportional hazards analyses to determine the association of social class and BMI with breast cancer incidence. RESULTS: Education was independently associated with increased risk of breast cancer incidence (hazard ratio [HR]=1.06; 95% confidence interval [CI]=1.01, 1.11; P<.05); contextual measures of social class were not. Education modified the effect of BMI at age 21 years (HR=0.98; 95% CI=0.97, 0.99); area-level social class modified the effect of BMI at baseline (HR=0.97; 95% CI=0.94, 0.99) and BMI change (HR=0.98; 95% CI=0.95, 1.00). Subpopulation analyses that were adjusted for hormone use, parity, and breast-feeding found similar effects. CONCLUSIONS: Social class moderates the influence of body size on breast cancer incidence. Public health efforts, therefore, should advocate for policies that improve social conditions to decrease the burden of breast cancer.

Trends and correlates in meat consumption patterns in the US adult population.

OBJECTIVE: Few studies have examined recent shifts in meat consumption (MC), differences among US population groups, and the influence of psychosocial-behavioural factors. DESIGN: Nationally representative data collected for US adults aged >or=18 years in the 1988-1994 and 1999-2004 National Health and Nutrition Examination Survey (NHANES) and the 1994-1996 Continuing Survey of Food Intakes by Individuals (CSFII) and Diet and Health Knowledge Survey (DHKS) were used. RESULTS: We found a U-shaped trend in MC, a decrease between 1988-1994 and 1994-1996, and an increase from 1994-1996 to 1999-2004. NHANES 1988-1994 and 1999-2004 indicate that MC did not change significantly, particularly for all meat, red meat, poultry and seafood. Between 1994-1996 and 1999-2004, average MC, including red meat, poultry, seafood and other meat products, increased in men. Women's total MC decreased, mainly due to decreased red meat and other meat products, except for increased seafood. Noticeable differences existed in the changes across population groups. Black men had the largest increase in consumption of total meat, poultry and seafood; Mexican American men had the smallest increase in poultry, seafood and other meat products. In 1999-2004, ethnic differences in MC became greater in women than among women in 1994-1996. Associations between MC and energy intake changed over time. Perceived benefit of dietary quality and food label use were associated with reduced red MC. CONCLUSIONS: Noticeable differences exist in the shifts in MC across population groups and surveys. MC increased in men but decreased in women in recent years.

Alternative functions of the BCL-2 protein family at the endoplasmic reticulum.

Apoptosis is essential for maintenance of tissue homeostasis and its deregulation results in a variety of disease conditions. The BCL-2 family of proteins is a group of evolutionarily conserved regulators of cell death that comprises both anti- and pro-apoptotic members, that operate at the mitochondrial membrane to control caspase activation. Different BCL-2-related proteins are also located in the endoplasmic reticulum (ER), where important roles in organelle physiology are proposed. Adaptation to ER stress is mediated by the activation of a complex signal transduction pathway known as the unfolded protein response (UPR). Recent reports indicate that the ER stress sensor IRE1alpha, signals through the formation of a protein complex platform at the ER membrane, here termed the "UPRosome". Alternatively, BCL-2 family members are contained in other multiprotein complexes at the ER that are involved in the control of diverse cellular processes including calcium homeostasis, autophagy and ER morphogenesis. Here we describe the emerging concept that BCL-2 family members are important regulators of essential cellular processes beyond apoptosis.

Resemblance in dietary intakes between urban low-income African-American adolescents and their mothers: the healthy eating and active lifestyles from school to home for kids study.

OBJECTIVES: To examine the association and predictors of dietary intake resemblance between urban low-income African-American adolescents and their mothers. METHODS: Detailed dietary data collected from 121 child-parent pairs in Chicago during fall 2003 were used. The association was assessed using correlation coefficients, kappa, and percentage of agreement, as well as logistic regression models. RESULTS: Overall, the association was weak as indicated by correlations and other measures. None of the mother-son correlations for nutrients and food groups were greater than 0.20. Mother-daughter pairs had stronger correlations (0.26 for energy and 0.30 for fat). The association was stronger in normal-weight mothers than in mothers with overweight or obesity. Logistic models showed that mother being a current smoker, giving child more pocket money, and allowing child to eat or purchase snacks without parental permission or presence predicted a higher probability of resemblance in undesirable eating patterns, such as high-energy, high-fat, and high-snack intakes (P<0.05). CONCLUSIONS: Mother-child diet association was generally weak, and varied considerably across groups and intake variables in this homogenous population. Some maternal characteristics seem to affect the association.