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The potential ability of nutritional compounds to induce or enhance the browning of adipocytes has attracted large interest as a workable means of combatting the obesity epidemic. Green tea compounds are discussed as such inducers of an enhanced thermogenic capacity and activity. However, the cell-autonomous effects of green tea compounds on adipocytes have until now only been demonstrated in adipogenic cell lines (3T3-L1 and 3T3-F442A), i.e., cells of undefined tissue lineage. In this study, we examine the ability of green tea compounds to cell-autonomously induce thermogenic recruitment in authentic brown and brite/beige adipocytes in vitro . In primary brown adipocytes, the green tea compounds suppressed basal UCP1 gene expression, and there was no positive interaction between the compounds and adrenergic stimulation. In white adipocytes, green tea compounds decreased both basal and norepinephrine-induced UCP1 mRNA levels, and this was associated with the suppression of cell differentiation, indicated by reduced lipogenic gene expression and lipid accumulation. A lack of interaction between rosiglitazone and green tea compounds suggests that the green tea compounds do not directly interact with the PPARγ pathway. We conclude that there is a negative effect of the green tea compounds on basal UCP1 gene expression, in both brown and white primary adipocytes, in contrast to the positive effects earlier reported from studies in adipogenic cell lines. We posit that the epigenetic status of the adipogenic cell lines is fundamentally different from that of genuine brown and white adipocytes, reflected, e.g., in several-thousand-fold differences in UCP1 gene expression levels. Thus, results obtained with adipogenic cell lines cannot unreservedly be extrapolated as being relevant for authentic effects in brown and white adipocytes. We suggest that this conclusion can be of general concern for studies attempting to establish physiologically relevant cell-autonomous effects., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Otton, Petrovic, Cannon and Nedergaard.)

PERK protein, that is canonically associated with the response to endoplasmic reticulum stress, may be acquiring a new role as a regulator of the growth of mitochondrial cristae. This role is pertinent not only to the recruitment of brown adipose tissue thermogenic capacity but probably also to directing cristae formation in highly metabolically active organs such as the heart., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

There are multiple conditions that can make children prone to having a sudden cardiac arrest (SCA) or sudden cardiac death (SCD). Efforts have been made by multiple organizations to screen children for cardiac conditions, but the emphasis has been on screening before athletic competition. This article is an update of the previous American Academy of Pediatrics policy statement of 2012 that addresses prevention of SCA and SCD. This update includes a comprehensive review of conditions that should prompt more attention and cardiology evaluation. The role of the primary care provider is of paramount importance in the evaluation of children, particularly as they enter middle school or junior high. There is discussion about whether screening should find any cardiac condition or just those that are associated with SCA and SCD. This update reviews the 4 main screening questions that are recommended, not just for athletes, but for all children. There is also discussion about how to handle post-SCA and SCD situations as well as discussion about genetic testing. It is the goal of this policy statement update to provide the primary care provider more assistance in how to screen for life-threatening conditions, regardless of athletic status., Competing Interests: POTENTIAL CONFLICT OF INTEREST: The authors have no potential conflicts of interest relevant to this article to disclose., (Copyright © 2021 by the American Academy of Pediatrics.)

A usual interstitial pneumonia (UIP) imaging pattern can be seen in both idiopathic pulmonary fibrosis (IPF) and connective tissue disease-related interstitial lung disease (CTD-ILD). The purpose of this multicenter study was to assess whether quantitative imaging data differ between IPF and CTD-ILD in the setting of UIP. Patients evaluated at two medical centers with CTD-ILD or IPF and a UIP pattern on CT or pathology served as derivation and validation cohorts. Chest CT data were quantitatively analyzed including total volumes of honeycombing, reticulation, ground-glass opacity, normal lung, and vessel related structures (VRS). VRS was compared with forced vital capacity percent predicted (FVC%) and percent predicted diffusing capacity of the lungs for carbon monoxide (DLCO%). There were 296 subjects in total, with 40 CTD-ILD and 85 IPF subjects in the derivation cohort, and 62 CTD-ILD and 109 IPF subjects in the validation cohort. VRS was greater in IPF across the cohorts on univariate ( p < 0.001) and multivariable ( p < 0.001-0.047) analyses. VRS was inversely correlated with DLCO% in both cohorts on univariate ( p < 0.001) and in the derivation cohort on multivariable analysis ( p = 0.003) but not FVC%. Total volume of normal lung was associated with DLCO% ( p < 0.001) and FVC% ( p < 0.001-0.009) on multivariable analysis in both cohorts. VRS appears to have promise in differentiating CTD-ILD from IPF. The underlying pathophysiological relationship between VRS and ILD is complex and is likely not explained solely by lung fibrosis.

Cold- and diet-induced recruitment of brown adipose tissue (BAT) and the browning of white adipose tissue (WAT) are dynamic processes, and the recruited state attained is a state of dynamic equilibrium, demanding continuous stimulation to be maintained. An involvement of macrophages, classical proinflammatory (M1) or alternatively activated anti-inflammatory (M2), is presently discussed as being an integral part of these processes. If these macrophages play a mediatory role in the recruitment process, such an involvement would have to be maintained in the recruited state. We have, therefore, investigated whether the recruited state of these tissues is associated with macrophage accretion or attrition. We found no correlation (positive or negative) between total UCP1 mRNA levels (as a measure of recruitment) and proinflammatory macrophages in any adipose depot. We found that in young chow-fed mice, cold-induced recruitment correlated with accretion of anti-inflammatory macrophages; however, such a correlation was not seen when cold-induced recruitment was studied in diet-induced obese mice. Furthermore, the anti-inflammatory macrophage accretion was mediated via β 1 /β 2 -adrenergic receptors; yet, in their absence, and thus in the absence of macrophage accretion, recruitment proceeded normally. We thus conclude that the classical recruited state in BAT and inguinal (brite/beige) WAT is not paralleled by macrophage accretion or attrition. Our results make mediatory roles for macrophages in the recruitment process less likely. NEW & NOTEWORTHY A regulatory or mediatory role-positive or negative-for macrophages in the recruitment of brown adipose tissue is presently discussed. As the recruited state in the tissue is a dynamic process, maintenance of the recruited state would need persistent alterations in macrophage complement. Contrary to this expectation, we demonstrate here an absence of alterations in macrophage complement in thermogenically recruited brown-or brite/beige-adipose tissues. Macrophage regulation of thermogenic capacity is thus less likely.

New Findings: What is the topic of this review? It has been suggested that human brown adipose tissue (BAT) is more similar to the brite/beige adipose tissue of mice than to classical BAT of mice. The basis of this is discussed in relationship to the physiological conditions of standard experimental mice. What advances does it highlight? We highlight that, provided mouse adipose tissues are examined under physiological conditions closer to those prevalent for most humans, the gene expression profile of mouse classical BAT is more similar to that of human BAT than is the profile of mouse brite/beige adipose tissue. Human BAT is therefore not different in nature from classical mouse BAT., Abstract: Since the presence of brown adipose tissue (BAT) was established in adult humans some 13 years ago, its physiological significance and molecular characteristics have been discussed. In particular, it has been proposed that the mouse adipose tissue depot most closely resembling and molecularly parallel to human BAT is not classical mouse BAT. Instead, so-called brite or beige adipose tissue, which is characteristically observed in the inguinal 'white' adipose tissue depot of mice, has been proposed to be the closest mouse equivalent of human BAT. We summarize here the published evidence examining this question. We emphasize the differences in tissue appearance and tissue transcriptomes from 'standard' mice [young, chow fed and, in effect semi-cold exposed (20°C)] versus 'physiologically humanized' mice [middle-aged, high-fat diet-fed mice living at thermoneutrality (30°C)]. We find that in the physiologically humanized mice, classical BAT displays molecular and cellular characteristics that are more akin to human BAT than are those of brite/beige adipose tissues from either standard or physiologically humanized mice. We suggest, therefore, that mouse BAT is the more relevant tissue for translational studies. This is an invited summary of a presentation given at Physiology 2019 (Aberdeen)., (© 2020 The Authors. Experimental Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.)

Background: The course of idiopathic pulmonary fibrosis (IPF) is uncertain with variable patterns of disease progression. We sought to evaluate the prognostic utility of the WBC, a routinely performed lab test, in a well-defined cohort of outpatient IPF subjects., Methods: We reviewed IPF patient records from two independent ILD centers (Inova Fairfax in Falls Church, VA, USA and Ege University Hospital in Izmir, Turkey) between 2007 and 2018. Demographics, CBC data, and patient outcomes were obtained. Survival differences were analyzed., Results: There were 436 IPF outpatients in the cohort with a median WBC of 8.9 × 10 9  cells per liter. For pragmatic purposes, patients were categorized into two groups, WBC ≥9 or WBC <9. Patients with WBC <9 had a median transplant-free survival of 50.5 months from the time of the CBC, compared to 32.4 months for those with WBC ≥9 (p < 0.0001). The association between WBC and attenuated survival remained significant after adjusting for GAP stage, steroid use, and antifibrotic use when WBC was analyzed both as a continuous (HR: 1.11; 95% CI: 1.05-1.17) and a dichotomized variable (high (WBC ≥9) vs. low (WBC <9), (HR: 1.53; 95% CI:1.09-2.15). WBC and absolute neutrophil count (ANC) were highly correlated suggesting that PMNs account for most of this association (r = 0.92)., Conclusions: Baseline WBC may impart important and readily available prognostic information in outpatients with IPF. Further studies are warranted to validate this as a potential biomarker for IPF, as well as to define the biologic basis for the association., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Wolff-Parkinson-White (WPW) syndrome is a relatively common arrhythmia affecting ~1-3/1,000 individuals. Mutations in PRKAG2 have been described in rare patients in association with cardiomyopathy. However, the genetic basis of WPW in individuals with a structurally normal heart remains poorly understood. Sudden death due to atrial fibrillation (AF) can also occur in these individuals. Several studies have indicated that despite ablation of an accessory pathway, the risk of AF remains high in patients compared to general population., Methods: We applied exome sequencing in 305 subjects, including 65 trios, 80 singletons, and 6 multiple affected families. We used de novo analysis, candidate gene approach, and burden testing to explore the genetic contributions to WPW., Results: A heterozygous deleterious variant in PRKAG2 was identified in one subject, accounting for 0.6% (1/151) of the genetic basis of WPW in this study. Another individual with WPW and left ventricular hypertrophy carried a known pathogenic variant in MYH7. We found rare de novo variants in genes associated with arrhythmia and cardiomyopathy (ANK2, NEBL, PITX2, and PRDM16) in this cohort. There was an increased burden of rare deleterious variants (MAF ≤ 0.005) with CADD score ≥ 25 in genes linked to AF in cases compared to controls (P = .0023)., Conclusions: Our findings show an increased burden of rare deleterious variants in genes linked to AF in WPW syndrome, suggesting that genetic factors that determine the development of accessory pathways may be linked to an increased susceptibility of atrial muscle to AF in a subset of patients., (© 2020 Wiley Periodicals, Inc.)

Animals that lack the hormone leptin become grossly obese, purportedly for 2 reasons: increased food intake and decreased energy expenditure (thermogenesis). This review examines the experimental evidence for the thermogenesis component. Analysis of the data available led us to conclude that the reports indicating hypometabolism in the leptin-deficient ob/ob mice (as well as in the leptin-receptor-deficient db/db mice and fa/fa rats) derive from a misleading calculation artefact resulting from expression of energy expenditure per gram of body weight and not per intact organism. Correspondingly, the body weight-reducing effects of leptin are not augmented by enhanced thermogenesis. Congruent with this, there is no evidence that the ob/ob mouse demonstrates atrophied brown adipose tissue or diminished levels of total UCP1 mRNA or protein when the ob mutation is studied on the inbred C57BL/6 mouse background, but a reduced sympathetic nerve activity is observed. On the outbred "Aston" mouse background, brown adipose tissue atrophy is seen, but whether this is of quantitative significance for the development of obesity has not been demonstrated. We conclude that leptin is not a thermogenic hormone. Rather, leptin has effects on body temperature regulation, by opposing torpor bouts and by shifting thermoregulatory thresholds. The central pathways behind these effects are largely unexplored., (© Endocrine Society 2019.)

Objectives: High-esterified pectin (HEP) is a prebiotic able to modulate gut microbiota, associated with health-promoting metabolic effects in glucose and lipid metabolism and adipostatic hormone sensitivity. Possible effects regulating adaptive thermogenesis and energy waste are poorly known. Therefore, we aimed to study how physiological supplementation with HEP is able to affect microbiota, energy metabolism and adaptive thermogenic capacity, and to contribute to the healthier phenotype promoted by HEP supplementation, as previously shown. We also attempted to decipher some of the mechanisms involved in the HEP effects, including in vitro experiments., Subjects and Experimental Design: We used a model of metabolic malprogramming consisting of the progeny of rats with mild calorie restriction during pregnancy, both under control diet and an obesogenic (high-sucrose) diet, supplemented with HEP, combined with in vitro experiments in primary cultured brown and white adipocytes treated with the postbiotic acetate., Results: Our main findings suggest that chronic HEP supplementation induces markers of brown and white adipose tissue thermogenic capacity, accompanied by a decrease in energy efficiency, and prevention of weight gain under an obesogenic diet. We also show that HEP promotes an increase in beneficial bacteria in the gut and peripheral levels of acetate. Moreover, in vitro acetate can improve adipokine production, and increase thermogenic capacity and browning in brown and white adipocytes, respectively, which could be part of the protection mechanism against excess weight gain observed in vivo., Conclusion: HEP and acetate stand out as prebiotic/postbiotic active compounds able to modulate both brown-adipocyte metabolism and browning and protect against obesity.

The possibility to use leptin therapeutically for lowering glucose levels in patients with type 1 diabetes has attracted interest. However, earlier animal models of type 1 diabetes are severely catabolic with very low endogenous leptin levels, unlike most patients with diabetes. Here, we aim to test glucose-lowering effects of leptin in novel, more human-like murine models. We examined the glucose-lowering potential of leptin in diabetic models of two types: streptozotocin-treated mice and mice treated with the insulin receptor antagonist S961. To prevent hypoleptinemia, we used combinations of thermoneutral temperature and high-fat feeding. Leptin fully normalized hyperglycemia in standard chow-fed streptozotocin-treated diabetic mice. However, more humanized physiological conditions (high-fat diets or thermoneutral temperatures) that increased adiposity - and thus also leptin levels - in the diabetic mice abrogated the effects of leptin, i.e., the mice developed leptin resistance also in this respect. The glucose-lowering effect of leptin was not dependent on the presence of the uncoupling protein-1 and was not associated with alterations in plasma insulin, insulin-like growth factor 1, food intake or corticosterone but fully correlated with decreased plasma glucagon levels and gluconeogenesis. An important implication of these observations is that the therapeutic potential of leptin as an additional treatment in patients with type 1 diabetes is probably limited. This is because such patients are treated with insulin and do not display low leptin levels. Thus, the potential for a glucose-lowering effect of leptin would already have been attained with standard insulin therapy, and further effects on blood glucose level through additional leptin cannot be anticipated.

Implantable loop recorders (ILR) are utilized for long-term rhythm monitoring. Typical placement of the Medtronic Reveal LINQ along the left parasternal border may compromise the quality and/or feasibility of future imaging studies. We sought to evaluate the utility of placing an ILR in the left anterior axillary position and the impact on the quality of cardiac imaging. We reviewed patients from May 2017 to June 2018 who had placement of a Reveal LINQ device in the left anterior axillary position. Demographic, procedural, and clinical data were collected via retrospective review. Cardiac magnetic resonance imaging (MRI) studies were reviewed for image quality after ILR placement. Eight patients met inclusion criteria for this study (median age 6 years, 50% female). Six patients (75%) had an ILR placed in the operating room, while all others were placed in the electrophysiology lab. All patients demonstrated acceptable R waves for diagnostic evaluation (median = 0.85 mV, range 0.24-1.7 mV). Cardiac MRI was obtained in 7 patients following ILR placement with diagnostic image quality and no adverse events. One device was explanted 28 days after placement due to concern for possible infection. No other devices required removal or revision (median follow up duration 11 months, IQR 8-13.5). ILR placement in the left anterior axillary position can record adequate signals in pediatric patients. In addition, axillary ILR device position may allow for completion of cardiac imaging, particularly cardiac MRI, without significant artifacts which is critical for patients with congenital heart disease.

Background: Heart Rhythm Society guidelines recommend obtaining thyroid function tests (TFTs) at amiodarone initiation and every 6 months thereafter in adults, with no specific pediatric recommendations. Untreated hypothyroidism in young children negatively affects brain development and somatic growth, yet the optimal screening frequency for pediatric patients remains unclear, and limited data exist on pediatric amiodarone-induced thyroid dysfunction., Objective: The purpose of this study was to describe the patterns of amiodarone-induced thyroid dysfunction in pediatric patients., Methods: We established a retrospective cohort of 527 pediatric patients who received amiodarone between 1997 and 2017. We defined amiodarone therapy lasting 3-30 days as "short term" and >30 days as "long term.", Results: The final cohort (n = 150) consisted of 27 neonates (18%), 25 infants (16%), 27 young children (18%), and 71 children (47%). Of the children in whom TFTs were checked, half (50.8%) developed a thyroid-stimulating hormone (TSH) value above the reference for age. Neonates had the highest median peak TSH values in both short- and long-term groups: 23.5 mIU/L (interquartile range 11.4-63.1) and 28.8 mIU/L (interquartile range 11.4-34.4), respectively. Although concurrent use of inotropic support was significantly associated with lower initial TSH values, no variable related to cardiac illness or type of heart disease was associated with peak TSH values., Conclusion: Neonates and infants receiving amiodarone had more thyroid dysfunction with greater degrees of TSH elevation than older children. TSH elevations occurred early, even with short-term exposure. Given the concern for brain development and growth in hypothyroid children, our results suggest the need for more rigorous pediatric-specific thyroid monitoring guidelines., (Copyright © 2019 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

We report on the measurement of the γp→J/ψp cross section from E&#95;{γ}=11.8  GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39  GeV^{-2} at 10.7 GeV average energy. The LHCb pentaquark candidates P&#95;{c}^{+} can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(P&#95;{c}^{+}→J/ψp) and cross sections σ(γp→P&#95;{c}^{+})×B(P&#95;{c}^{+}→J/ψp).

Human and rodent brown adipose tissues (BAT) appear morphologically and molecularly different. Here we compare human BAT with both classical brown and brite/beige adipose tissues of 'physiologically humanized' mice: middle-aged mice living under conditions approaching human thermal and nutritional conditions, that is, prolonged exposure to thermoneutral temperature (approximately 30 °C) and to an energy-rich (high-fat, high-sugar) diet. We find that the morphological, cellular and molecular characteristics (both marker and adipose-selective gene expression) of classical brown fat, but not of brite/beige fat, of these physiologically humanized mice are notably similar to human BAT. We also demonstrate, both in silico and experimentally, that in physiologically humanized mice only classical BAT possesses a high thermogenic potential. These observations suggest that classical rodent BAT is the tissue of choice for translational studies aimed at recruiting human BAT to counteract the development of obesity and its comorbidities.

A reduction in the thermogenic activity of brown adipose tissue (BAT) is presently discussed as a possible determinant for the development of obesity in humans. One group of endogenous factors that could potentially affect BAT activity is the glucocorticoids (e.g. cortisol). We analyse here studies examining the effects of alterations in glucocorticoid signaling on BAT recruitment and thermogenic capacity. We find that irrespective of which manipulation of glucocorticoid signaling is examined, a seemingly homogeneous picture of lowered thermogenic capacity due to glucocorticoid stimulation is apparently obtained: e.g. lowered uncoupling protein 1 (UCP1) protein levels per mg protein, and an increased lipid accumulation in BAT. However, further analyses generally indicate that these effects result from a dilution effect rather than a true decrease in total capacity; the tissue may thus be said to be in a state of pseudo-atrophy. However, under conditions of very low physiological stimulation of BAT, glucocorticoids may truly inhibit Ucp1 gene expression and consequently lower total UCP1 protein levels, but the metabolic effects of this reduction are probably minor. It is thus unlikely that glucocorticoids affect organismal metabolism and induce the development of obesity through alterations of BAT activity., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Burnout affects large portions of the healthcare workforce and is associated with increased medical errors, decreased patient experience and adherence, loss of professionalism, and decreased productivity. Little data exists on how novel clinical care settings might impact burnout. We studied the experience and burnout of staff involved in a home hospital pilot, where acutely ill patients were cared for at home as a substitute for traditional hospitalization., Methods: We analyzed evaluations completed by home hospital staff (physicians, registered nurses, and research assistants) at the conclusion of a 2-month pilot program. Our primary outcome was burnout evaluated by the Mini Z Burnout Survey. Secondary outcomes included overall job satisfaction, work environment, workload, and team evaluation measured on a 5-point Likert scale., Results: Eight of nine (89%) staff completed evaluations. Seven of eight (88%) staff had no symptoms of burnout; one (13%) was under stress but did not feel burned out. Median overall satisfaction with home hospital was 4.5/5.0 (interquartile range (IQR), 1.0). Most staff (6/8; 75%) "strongly agreed" that their professional values were well-aligned with the program. Three of six (50%) "entirely" or "very much" preferred home hospital to their standard clinical setting. Six of eight (75%) staff felt that their opinions were "entirely" heard; four of eight (50%) felt the team "entirely" valued each of its participants., Conclusions: Novel clinical care settings like home hospital may lead to low staff burnout, high job satisfaction, and a healthy work environment. Further study is warranted., Competing Interests: The authors have no conflict of interest to disclose.

Objective: Hyperthyroidism is associated with increased metabolism ("thyroid thermogenesis") and elevated body temperature, often referred to as hyperthermia. Uncoupling protein-1 (UCP1) is the protein responsible for nonshivering thermogenesis in brown adipose tissue. We here examine whether UCP1 is essential for thyroid thermogenesis., Methods: We investigated the significance of UCP1 for thyroid thermogenesis by using UCP1-ablated (UCP1 KO) mice. To avoid confounding factors from cold-induced thermogenesis and to approach human conditions, the experiments were conducted at thermoneutrality, and to resemble conditions of endogenous release, thyroid hormone (thyroxine, T4) was injected peripherally., Results: Both short-term and chronic thyroxine treatment led to a marked increase in metabolism that was largely UCP1-independent. Chronic thyroxine treatment led to a 1-2 °C increase in body temperature. This increase was also UCP1-independent and was maintained even at lower ambient temperatures. Thus, it was pyrexia, i.e. a defended increase in body temperature, not hyperthermia. In wildtype mice, chronic thyroxine treatment induced a large relative increase in the total amounts of UCP1 in the brown adipose tissue (practically no UCP1 in brite/beige adipose tissue), corresponding to an enhanced thermogenic response to norepinephrine injection. The increased UCP1 amount had minimal effects on thyroxine-induced thermogenesis and pyrexia., Conclusions: These results establish that thyroid thermogenesis is a UCP1-independent process. The fact that the increased metabolism coincides with elevated body temperature and thus with accelerated kinetics accentuates the unsolved issue of the molecular background for thyroid thermogenesis., (Copyright © 2019 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: Idiopathic Pulmonary Fibrosis (IPF) is a fatal lung disease of unknown etiology with only two federally approved drug options. Given the complex molecular pathogenesis of IPF involving multiple cell types and multiple pathways, we explore the effects of a potential antifibrotic and antioxidant drug combination. Curcumin is a polyphenolic compound derived from turmeric with significant biological activity including a potential antifibrotic capacity. N-acetylcysteine (NAC) is a precursor to the antioxidant glutathione. To advance our understanding of these molecules, and to identify a clinical application, we present a small number of focused experiments that interrogates the effect of curcumin and NAC on pathways relevant to IPF in both fibroblasts and epithelial cells., Methods: Primary epithelial cell and fibroblasts isolated from patients with IPF were challenged with a combination treatment of NAC and curcumin. Evaluation of the antifibrotic potential and effect on oxidative stress was performed through QPCR gene expression analysis and functional assays including scratch tests, viability assays, and measurement of induced reactive oxygen species., Results: We demonstrate that curcumin alone does have antifibrotic potential, but that effect is accompanied by proapoptotic increases in oxidative stress. Coupled with this, we find that NAC alone can reduce oxidative stress, but that epithelial cell viability is decreased through this treatment. However, co-administration of these two molecules decreases oxidative stress and maintains high cell viability in both cell types. In addition, this co-treatment maintains an antifibrotic potential., Conclusions: These findings suggest a novel application for these molecules in IPF and encourage further exploration of this potential therapeutic approach.

An excess of glucocorticoids leads to the development of obesity in both mice and humans, but the mechanism for this is unknown. Here, we determine the extent to which decreased BAT thermogenic capacity (as a result of glucocorticoid treatment) contributes to the development of obesity. Contrary to previous suggestions, we show that only in mice housed at thermoneutrality (30°C) does corticosterone treatment reduce total BAT UCP1 protein. This reduction is reflected in reduced brown adipocyte cellular and mitochondrial UCP1-dependent respiration. However, glucocorticoid-induced obesity develops to the same extent in animals housed at 21°C and 30°C, whereas total BAT UCP1 protein levels differ 100-fold between the two groups. In corticosterone-treated wild-type and UCP1 knockout mice housed at 30°C, obesity also develops to the same extent. Thus, our results demonstrate that the development of glucocorticoid-induced obesity is not caused by a decreased UCP1-dependent thermogenic capacity., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

The attractive tenet that recruitment and activation of brown adipose tissue (BAT) and uncoupling protein 1 (UCP1) could counteract the development of obesity and its comorbidities in humans has been experimentally corroborated mainly by experiments demonstrating that UCP1-ablated mice on a C57Bl/6 background (exempt from thermal stress) become more obese when fed a high-fat diet. However, concerns may be raised that this outcome of UCP1 ablation is restricted to this very special inbred and particularly obesity-prone mouse strain. Therefore, we have examined to which degree UCP1 ablation has similar metabolic effects in a mouse strain known to be obesity resistant: the 129S strain. For this, male 129S2/sv or 129SV/Pas mice and corresponding UCP1-knockout mice were fed chow or a high-fat or a cafeteria diet for 4 wk. The absence of UCP1 augmented obesity (weight gain, body fat mass, %body fat, fat depot size) in high-fat diet- and cafeteria-fed mice, with a similar or lower food intake, indicating that, when present, UCP1 indeed decreases metabolic efficiency. The increased obesity was due to a decrease in energy expenditure. The consumption of a high-fat or cafeteria diet increased total BAT UCP1 protein levels in wild-type mice, and correspondingly, high-fat diet and cafeteria diet-fed mice demonstrated increased norepinephrine-induced oxygen consumption. There was a positive correlation between body fat and total BAT UCP1 protein content. No evidence for diet-induced adrenergic thermogenesis was found in UCP1-ablated mice. Thus, the obesity-reducing effect of UCP1 is not restricted to a particular, and perhaps not representative, mouse strain.

The possibility that recruitment and activation of brown adipose tissue (BAT) thermogenesis could be beneficial for curtailing obesity development in humans prompts a need for a better understanding of the control of these processes [that are often referred to collectively as diet-induced thermogenesis (DIT)]. Dietary conditions are associated with large changes in blood-borne factors that could be responsible for BAT recruitment, but BAT is also innervated by the sympathetic nervous system. To examine the significance of the innervation for DIT recruitment, we surgically denervated the largest BAT depot, i.e., the interscapular BAT depot in mice and exposed the mice at thermoneutrality to a high-fat diet versus a chow diet. Denervation led to an alteration in feeding pattern but did not lead to enhanced obesity, but obesity was achieved with a lower food intake, as denervation increased metabolic efficiency. Conclusively, denervation totally abolished the diet-induced increase in total UCP1 protein levels observed in the intact mice, whereas basal UCP1 expression was not dependent on innervation. The denervation of interscapular BAT did not discernably hyper-recruit other BAT depots, and no UCP1 protein could be detected in the principally browning-competent inguinal white adipose tissue depot under any of the examined conditions. We conclude that intact innervation is essential for diet-induced thermogenesis and that circulating factors cannot by themselves initiate recruitment of brown adipose tissue under obesogenic conditions. Therefore, the processes that link food intake and energy storage to activation of the nervous system are those of significance for the further understanding of diet-induced thermogenesis.

Three-way helical junctions (3WJs) arise in genetic processing, and they have architectural and functional roles in structured nucleic acids. An internal bulge at the junction core allows the helical domains to become oriented into two possible, coaxially stacked conformers. Here, the helical stacking arrangements for a series of bulged, DNA 3WJs were examined using ensemble fluorescence resonance energy transfer (FRET) and single-molecule FRET (smFRET) approaches. The 3WJs varied according to the GC content and sequence of the junction core as well as the pyrimidine content of the internal bulge. Mg 2+ titration experiments by ensemble FRET show that both stacking conformations have similar Mg 2+ requirements for folding. Strikingly, smFRET experiments reveal that a specific junction sequence can populate both conformers and that this junction undergoes continual interconversion between the two stacked conformers. These findings will support the development of folding principles for the rational design of functional DNA nanostructures., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In mice living under normal animal house conditions, the brown adipocytes in classical brown adipose tissue depots are already essentially fully differentiated: UCP1 mRNA and UCP1 protein levels are practically saturated. This means that any further recruitment - in response to cold exposure or any other browning agent - does not result in significant augmentation of these parameters. This may easily be construed to indicate that classical brown adipose tissue cannot be further recruited. However, this is far from the case: the capacity for further recruitment instead lies in the ability of the tissue to increase the number of brown-fat cells, a remarkable and highly controlled physiological recruitment process. We have compiled here the available data concerning the unique ability of norepinephrine to increase cell proliferation and inhibit apoptosis in brown adipocytes. Adrenergically stimulated cell proliferation is fully mediated via β 1 -adrenoceptors and occurs through activation of stem cells in the tissue; intracellular mediation of the signal involves cAMP and protein kinase A activation, but activation of Erk1/2 is not part of the pathway. Apoptosis inhibition in brown adipocytes is induced by both β- and α 1 -adrenergic receptors and here the intracellular pathway includes Erk1/2 activation. This unique ability of norepinephrine to increase cell number in an apparently mitogenically dormant tissue provides possibilities to augment the metabolic capacity of brown adipose tissue, also for therapeutic purposes., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Repetitive trinucleotide DNA sequences at specific genetic loci are associated with numerous hereditary, neurodegenerative diseases. The propensity of single-stranded domains containing these sequences to form secondary structure via extensive self-complementarity disrupts normal DNA processing to create genetic instabilities. To investigate these intrastrand structural dynamics, a DNA hairpin system was devised for single-molecule fluorescence study of the folding kinetics and energetics for secondary structure formation between two interacting, repetitive domains with specific numbers of the same trinucleotide motif (CXG), where X = T or A. Single-molecule fluorescence resonance energy transfer (smFRET) data show discrete conformational transitions between unstructured and closed hairpin states. The lifetimes of the closed hairpin states correlate with the number of repeats, with (CTG) N /(CTG) N domains maintaining longer-lived, closed states than equivalent-sized (CAG) N /(CAG) N domains. NaCl promotes similar degree of stabilization for the closed hairpin states of both repeat sequences. Temperature-based, smFRET experiments reveal that NaCl favors hairpin closing for (CAG) N /(CAG) N by preordering single-stranded repeat domains to accelerate the closing transition. In contrast, NaCl slows the opening transition of CTG hairpins; however, it promotes misfolded conformations that require unfolding. Energy diagrams illustrate the distinct folding pathways of (CTG) N and (CAG) N repeat domains and identify features that may contribute to their gene-destabilizing effects.

Objectives: Fasciculo-ventricular (FV) accessory pathways (AP's) and right anteroseptal (RAS) AP's share similar anatomic locations and electrocardiographic characteristics. The objective of this article is to compare these features in children., Methods: All patients with manifest pre-excitation who underwent an electrophysiological study were included. Fasciculo-ventricular AP's were defined by the presence of an HV interval≤32ms and a prolongation of the AH without changes in the HV interval, or the level of pre-excitation during atrial pacing. Three independent and blind observers analysed the ECG's in both groups., Results: Out of 288 patients, 15 (5.2%) had FV AP's and 14 (4.9%) right AS AP's. The PR interval was longer in FV AP's than in RAS (113±21 vs 86±13ms respectively; P<.001) and the QRS was narrower (95±12 vs 137±24ms respectively; P<.001). The ECG in patients with FV AP's showed a rapid low amplitude deflection at the begining of the QRS in 13 out of 15 patients (87%) and in 2 (14%) the RAS AP group (P=.003)., Conclusions: The PR interval was longer and the QRS complex was narrower in patients with FV AP's. The presence of a rapid low amplitude deflection at the beginning of the QRS complex would allow to differentiate them from RAS AP's non-invasively., (Copyright © 2017 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.)

An investigation was carried out on the polarization attraction (PA) of a polarization-scrambled 10.7-GBaud NRZ-BPSK signal in a 1-km-long highly nonlinear fiber (HNLF). For the back-to-back case, PA on an ASE-loaded signal yielded a receiver sensitivity penalty of ≈ 14.5 dB at the ITU-T G.975.1.I3 FEC threshold of 3.5 × 10 -3 , relative to matched-filter reception theory. After long-haul 100-GHz DWDM transmission in a recirculating loop, PA on the output signal was found to achieve approximately the same receiver sensitivity performance, as that of the back-to-back case. From these experiments, it is concluded that the Gordon-Mollenauer effect due to propagation in the HNLF during PA dominates other impairments including those arising from the long-haul 100-GHz DWDM recirculating loop transmission.

In April 2016, a Virginia dentist who had recently received a diagnosis of idiopathic pulmonary fibrosis (IPF) and was undergoing treatment at a specialty clinic at a Virginia tertiary care center contacted CDC to report concerns that IPF had been diagnosed in multiple Virginia dentists who had sought treatment at the same specialty clinic. IPF is a chronic, progressive lung disease of unknown cause and associated with a poor prognosis (1). Although IPF has been associated with certain occupations (2), no published data exist regarding IPF in dentists. The medical records for all 894 patients treated for IPF at the Virginia tertiary care center during September 1996-June 2017 were reviewed for evidence that the patient had worked as a dentist, dental hygienist, or dental technician; among these patients, eight (0.9%) were identified as dentists and one (0.1%) as a dental technician, and each had sought treatment during 2000-2015. Seven of these nine patients had died. A questionnaire was administered to one of the living patients, who reported polishing dental appliances and preparing amalgams and impressions without respiratory protection. Substances used during these tasks contained silica, polyvinyl siloxane, alginate, and other compounds with known or potential respiratory toxicity. Although no clear etiologies for this cluster exist, occupational exposures possibly contributed. This cluster of IPF cases reinforces the need to understand further the unique occupational exposures of dental personnel and the association between these exposures and the risk for developing IPF so that appropriate strategies can be developed for the prevention of potentially harmful exposures., Competing Interests: No conflicts of interest were reported.

Much current understanding of brown adipocyte development comes from in-vitro cell models. Serum type may affect the behavior of cultured cells and thus conclusions drawn. Here, we investigate effects of serum type ("fetal bovine" versus "newborn calf") on responses to differentiation inducers (the PPARγ agonist rosiglitazone or the neurotransmitter norepinephrine) in cultured primary brown adipocytes. Lipid storage was enhanced by fetal versus newborn serum. However, molecular adipose conversion (Pparg2 and Fabp4 expression) was not affected by serum type. Rosiglitazone-induced (7-days) expression of thermogenic genes (i.e. Ucp1, Pgc1a, Dio2 and Elovl3) was not systematically affected by serum type. However, importantly, acute (2 h) norepinephrine-induced thermogenic gene expression was overall markedly higher (and adipose genes somewhat lower) in cells cultured in newborn serum. Thus, newborn serum promotes thermogenic competence, and the use of fetal serum in brown adipocyte cultures (as is often routine) counteracts adequate differentiation. Agents that counteract this inhibition may therefore confoundingly be ascribed genuine thermogenic competence-inducing properties.

Extra heat for defense of body temperature can be obtained from shivering or nonshivering thermogenesis. Nonshivering thermogenesis is a facultative (i.e., only occurring when needed) and adaptive (i.e., being augmented when the demand is chronically higher) process that, in mammals, is the result of the activity of uncoupling protein-1 (UCP1) in brown and brownish adipose tissues; no other quantitatively significant mechanism that fulfills the above criteria has been established. Measurement of heat production is generally indirect, based on oxygen consumption. Heat from brown adipose tissue is generated in mammals adapted to cold, in mammalian neonates, and in mammalian hibernators during arousal; brown adipose tissue may also be active in obese mammals and thus partially protect against further obesity. UCP1 is innately inhibited by cytosolic adenosine triphosphate (ATP) and is likely activated by fatty acids released from triglycerides within the cells; this lipolysis is stimulated by norepinephrine released from the sympathetic nerves innervating the tissue. For prolonged thermogenesis, substrate is delivered by the circulation as chylomicrons, lipoproteins, fatty acids, and glucose. The proton gradient over the mitochondrial membrane created by the respiratory chain is dispersed through the activity of UCP1; brown adipose tissue is nearly devoid of ATP synthase (as compared to respiratory chain activity). UCP1 developed likely at the dawn of mammalian evolution; most mammalian species still retain functional UCP1. Other members of the uncoupling protein family cannot uncouple. Both newborn and adult humans possess active brown adipose tissue but the significance of the tissue for adult human metabolism is not established., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objectives: The laboratory mouse is presently the most common model for examining mechanisms of human physiology and disease. Housing temperatures can have a large impact on the outcome of such experiments and on their translatability to the human situation. Humans usually create for themselves a thermoneutral environment without cold stress, while laboratory mice under standard conditions (≈20° C) are under constant cold stress. In a well-cited, theoretical paper by Speakman and Keijer in Molecular Metabolism, it was argued that housing mice under close to standard conditions is the optimal way of modeling the human metabolic situation. This tenet was mainly based on the observation that humans usually display average metabolic rates of about 1.6 times basal metabolic rate. The extra heat thereby produced would also be expected to lead to a shift in the 'lower critical temperature' towards lower temperatures., Methods: To examine these tenets experimentally, we performed high time-resolution indirect calorimetry at different environmental temperatures on mice acclimated to different housing temperatures., Results: Based on the high time-resolution calorimetry analysis, we found that mice already under thermoneutral conditions display mean diurnal energy expenditure rates 1.8 times higher than basal metabolism, remarkably closely resembling the human situation. At any temperature below thermoneutrality, mice metabolism therefore exceeds the human equivalent: Mice under standard conditions display energy expenditure 3.1 times basal metabolism. The discrepancy to previous conclusions is probably attributable to earlier limitations in establishing true mouse basal metabolic rate, due to low time resolution. We also found that the fact that mean energy expenditure exceeds resting metabolic rate does not move the apparent thermoneutral zone (the lower critical temperature) downwards., Conclusions: We show that housing mice at thermoneutrality is an advantageous step towards aligning mouse energy metabolism to human energy metabolism., (Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Background: The increased incidence of preoperative and postoperative arrhythmia in Ebstein anomaly (EA) prompted some clinicians to perform an electrophysiology study (EPS) in all patients prior to surgery for EA. The cone repair (CR) is the current surgical option of choice for most young patients with EA but the effect of the CR on arrhythmia is not well established., Objectives: To assess the burden of arrhythmia in young patients after CR and to assess the utility of selective preoperative EPS., Materials and Methods: A retrospective review of all patients <21 years of age with EA who had a CR at Mayo Clinic from June 2007 to December 2015 was performed. Surveys were mailed and telephone calls were made to all individuals to assess antiarrhythmic medication use and EP/device procedures performed after CR., Results: There were 143 patients; median age, 10 years (0.1-20.9 years). Thirty-five (24%) patients had a preoperative EPS of which 26 (18%) had a preoperative ablation. Indications for EPS were Wolff-Parkinson-White (WPW), documented arrhythmia, or suspected arrhythmia. Posthospital discharge data were available for 140 (98%) patients. Mean follow-up was 2.9 years (0.1-9.2 years). At follow-up, 7 (5%) patients were receiving antiarrhythmic medications. After CR, only 3 (2%) patients who did not have a preoperative EPS have required an ablation., Conclusions: The risk of arrhythmia after CR for EA in young patients is very low when a preoperative EPS is limited to those with WPW, known arrhythmia, or suspected arrhythmia. In smaller patients, it may be reasonable to defer the EPS., (© 2018 Wiley Periodicals, Inc.)

Internal loops within structured nucleic acids disrupt local base stacking and destabilize neighboring helical domains; however, these structural motifs also expand the conformational and functional capabilities of structured nucleic acids. Variations in the size, distribution of loop nucleotides on opposing strands (strand asymmetry), and sequence alter their biophysical properties. Here, the thermodynamics and structural flexibility of oligo-T-rich DNA internal loops were systematically investigated in terms of loop size and strand asymmetry. From optical melting experiments, a thermodynamic prediction model is proposed for the energetic penalty of internal loops that accounts for diminishing enthalpic and increasing entropic contributions due to loop size and strand asymmetry for bulges, asymmetric loops, and symmetric loops. These single-stranded domains become less sequence-dependent and more polymeric as the loop size increases. Single-molecule fluorescence resonance energy transfer studies reveal a gradual transition in conformation and structural flexibility from an elongated domain to an increasingly flexible bend that results from increasing strand asymmetry. The findings provide a framework for understanding the thermodynamic and conformational effects of internal loops for the rational design of functional DNA nanostructures.

We thought we knew how the heat-producing uncoupling protein 1 in brown adipose tissue was activated: by fatty acids released upon lipid droplet breakdown in the brown adipocytes. However, two studies in this issue (Schreiber et al., 2017; Shin et al., 2017) imply that this classical model may not be valid: heat can be produced in brown fat without intracellular lipolysis., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The significance of diet-induced thermogenesis (DIT) for metabolic control is still debated. Although obesogenic diets recruit UCP1 and adrenergically inducible thermogenesis, and although the absence of UCP1 may promote the development of obesity, no actual UCP1-related thermogenesis identifiable as diet-induced thermogenesis has to date been unambiguously demonstrated. Examining mice living at thermoneutrality, we have identified a process of facultative (directly elicited by acute eating), adaptive (magnitude develops over weeks on an obesogenic diet), and fully UCP1-dependent thermogenesis. We found no evidence for UCP1-independent diet-induced thermogenesis. The thermogenesis was proportional to the total amount of UCP1 protein in brown adipose tissue and was not dependent on any contribution of UCP1 in brite/beige adipose tissue, since no UCP1 protein was found there under these conditions. Total UCP1 protein amount developed proportionally to total body fat content. The physiological messenger linking obesity level and acute eating to increased thermogenesis is not known. Thus UCP1-dependent diet-induced thermogenesis limits obesity development during exposure to obesogenic diets but does not prevent obesity as such., (Copyright © 2017 the American Physiological Society.)

Despite the high rates of breast cancer among young Mexican women, their special needs and concerns have not been systematically addressed. To fulfill these unsatisfied demands, we have developed "Joven & Fuerte: Program for Young Women with Breast Cancer in Mexico," the first program dedicated to the care of young breast cancer patients in Latin America, which is taking place at the National Cancer Institute of Mexico and the two medical facilities of the Instituto Tecnológico y de Estudios Superiores de Monterrey. The program was created to optimize the complex clinical and psychosocial care of these patients, enhance education regarding their special needs, and promote targeted research, as well as to replicate this program model in other healthcare centers across Mexico and Latin America. From November 2013 to February 2017, the implementation of the "Joven & Fuerte" program has delivered specialized care to 265 patients, through the systematic identification of their particular needs and the provision of fertility, genetic, and psychological supportive services. Patients and families have engaged in pedagogic activities and workshops and have created a motivated and empowered community. The program developed and adapted the first educational resources in Spanish dedicated for young Mexican patients, as well as material for healthcare providers. As for research, a prospective cohort of young breast cancer patients was established to characterize clinicopathological features and psychosocial effects at baseline and during follow-up, as a guide for the development of specific cultural interventions addressing this vulnerable group. Eventually, it is intended that the program's organization and structure can reach national and international interactions and serve as a platform for other countries.

Brown and brite/beige adipocytes are attractive therapeutic targets to treat metabolic diseases. To maximally utilize their functional potential, further understanding is required about their identities and their functional differences. Recent studies with β 3 -adrenergic receptor knockout mice reported that brite/beige adipocytes, but not classical brown adipocytes, require the β 3 -adrenergic receptor for cold-induced transcriptional activation of thermogenic genes. We aimed to further characterize this requirement of the β 3 -adrenergic receptor as a functional distinction between classical brown and brite/beige adipocytes. However, when comparing wild-type and β 3 -adrenergic receptor knockout mice, we observed no differences in cold-induced thermogenic gene expression ( Ucp1 , Pgc1a , Dio2 , and Cidea ) in brown or white (brite/beige) adipose tissues. Irrespective of the duration of the cold exposure or the sex of the mice, we observed no effect of the absence of the β 3 -adrenergic receptor. Experiments with the β 3 -adrenergic receptor agonist CL-316,243 verified the functional absence of β 3 -adrenergic signaling in these knockout mice. The β 3 -adrenergic receptor knockout model in the present study was maintained on a FVB/N background, whereas earlier reports used C57BL/6 and 129Sv mice. Thus our data imply background-dependent differences in adrenergic signaling mechanisms in response to cold exposure. Nonetheless, the present data indicate that the β 3 -adrenergic receptor is dispensable for cold-induced transcriptional activation in both classical brown and, as opposed to earlier studies, brite/beige cells., (Copyright © 2017 the American Physiological Society.)

Adaptive thermogenesis is the process of heat generation in response to cold stimulation. It is under the control of the sympathetic nervous system, whose chief effector is the catecholamine norepinephrine (NE). NE enhances thermogenesis through β3-adrenergic receptors to activate brown adipose tissue and by 'browning' white adipose tissue. Recent studies have reported that alternative activation of macrophages in response to interleukin (IL)-4 stimulation induces the expression of tyrosine hydroxylase (TH), a key enzyme in the catecholamine synthesis pathway, and that this activation provides an alternative source of locally produced catecholamines during the thermogenic process. Here we report that the deletion of Th in hematopoietic cells of adult mice neither alters energy expenditure upon cold exposure nor reduces browning in inguinal adipose tissue. Bone marrow-derived macrophages did not release NE in response to stimulation with IL-4, and conditioned media from IL-4-stimulated macrophages failed to induce expression of thermogenic genes, such as uncoupling protein 1 (Ucp1), in adipocytes cultured with the conditioned media. Furthermore, chronic treatment with IL-4 failed to increase energy expenditure in wild-type, Ucp1 -/- and interleukin-4 receptor-α double-negative (Il4ra -/- ) mice. In agreement with these findings, adipose-tissue-resident macrophages did not express TH. Thus, we conclude that alternatively activated macrophages do not synthesize relevant amounts of catecholamines, and hence, are not likely to have a direct role in adipocyte metabolism or adaptive thermogenesis.

Competing Interests: Part of the content of this article was previously presented by the authors at a workshop at the American Association of Directors of Psychiatry Residency Training Annual Meeting, Austin, Texas, March 3–5, 2016.

The possibility that brown adipose tissue thermogenesis can be recruited in order to combat the development of obesity has led to a high interest in the identification of "browning agents", i.e. agents that increase the amount and activity of UCP1 in brown and brite/beige adipose tissues. However, functional analysis of the browning process yields confusingly different results when the analysis is performed in one of two alternative steps. Thus, in one of the steps, using cold acclimation as a potent model browning agent, we find that if the browning process is followed in mice initially housed at 21 °C (the most common procedure), there is only weak molecular evidence for increases in UCP1 gene expression or UCP1 protein abundance in classical brown adipose tissue; however, in brite/beige adipose depots, there are large increases, apparently associating functional browning with events only in the brite/beige tissues. Contrastingly, in another step, if the process is followed starting with mice initially housed at 30 °C (thermoneutrality for mice, thus similar to normal human conditions), large increases in UCP1 gene expression and UCP1 protein abundance are observed in the classical brown adipose tissue depots; there is then practically no observable UCP1 gene expression in brite/beige tissues. This apparent conundrum can be resolved when it is realized that the classical brown adipose tissue at 21 °C is already essentially fully differentiated and thus expands extensively through proliferation upon further browning induction, rather than by further enhancing cellular differentiation. When the limiting factor for thermogenesis, i.e. the total amount of UCP1 protein per depot, is analyzed, classical brown adipose tissue is by far the predominant site for the browning process, irrespective of which of the two steps is analyzed. There are to date no published data demonstrating that alternative browning agents would selectively promote brite/beige tissues versus classical brown tissue to a higher degree than does cold acclimation. Thus, to restrict investigations to examine adipose tissue depots where only a limited part of the adaptation process occurs (i.e. the brite/beige tissues) and to use initial conditions different from the thermoneutrality normally experienced by adult humans may seriously hamper the identification of therapeutically valid browning agents. The data presented here have therefore important implications for the analysis of the potential of browning agents and the nature of human brown adipose tissue., (Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.)

MtDNA mutator mice exhibit marked features of premature aging. We find that these mice treated from age of ≈100 days with the mitochondria-targeted antioxidant SkQ1 showed a delayed appearance of traits of aging such as kyphosis, alopecia, lowering of body temperature, body weight loss, as well as ameliorated heart, kidney and liver pathologies. These effects of SkQ1 are suggested to be related to an alleviation of the effects of an enhanced reactive oxygen species (ROS) level in mtDNA mutator mice: the increased mitochondrial ROS released due to mitochondrial mutations probably interact with polyunsaturated fatty acids in cardiolipin, releasing malondialdehyde and 4-hydroxynonenal that form protein adducts and thus diminishes mitochondrial functions. SkQ1 counteracts this as it scavenges mitochondrial ROS. As the results, the normal mitochondrial ultrastructure is preserved in liver and heart; the phosphorylation capacity of skeletal muscle mitochondria as well as the thermogenic capacity of brown adipose tissue is also improved. The SkQ1-treated mice live significantly longer (335 versus 290 days). These data may be relevant in relation to treatment of mitochondrial diseases particularly and the process of aging in general.

Cidea is a gene highly expressed in thermogenesis-competent (UCP1-containing) adipose cells, both brown and brite/beige. Here, we initially demonstrate a remarkable adipose-depot specific regulation of Cidea expression. In classical brown fat, Cidea mRNA is expressed continuously and invariably, irrespective of tissue recruitment. However, Cidea protein levels are regulated posttranscriptionally, being conspicuously induced in the thermogenically recruited state. In contrast, in brite fat, Cidea protein levels are regulated at the transcriptional level, and Cidea mRNA and protein levels are proportional to tissue "briteness." Although routinely followed as a thermogenic molecular marker, Cidea function is not clarified. Here, we employed a gain-of-function approach to examine a possible role of Cidea in the regulation of thermogenesis. We utilized transgenic aP2-hCidea mice that overexpress human Cidea in all adipose tissues. We demonstrate that UCP1 activity is markedly suppressed in brown-fat mitochondria isolated from aP2-hCidea mice. However, mitochondrial UCP1 protein levels were identical in wild-type and transgenic mice. This implies a regulatory effect of Cidea on UCP1 activity, but as we demonstrate that Cidea itself is not localized to mitochondria, we propose an indirect inhibitory effect. The Cidea-induced inhibition of UCP1 activity (observed in isolated mitochondria) is physiologically relevant since the mice, through an appropriate homeostatic compensatory mechanism, increased the total amount of UCP1 in the tissue to exactly match the diminished thermogenic capacity of the UCP1 protein and retain unaltered nonshivering thermogenic capacity. Thus, we verified Cidea as being a marker of thermogenesis-competent adipose tissues, but we conclude that Cidea, unexpectedly, functions molecularly as an indirect inhibitor of thermogenesis., (Copyright © 2017 the American Physiological Society.)