Maternal genetics and diet modulate vitamin A homeostasis of the offspring and affect the susceptibility to obesity in adulthood in mice.

Perinatal nutrition exerts a profound influence on adult metabolic health. This study aimed to investigate whether increased maternal vitamin A (VA) supply can lead to beneficial metabolic phenotypes in the offspring. The researchers utilized mice deficient in the intestine-specific homeobox (ISX) transcription factor, which exhibit increased intestinal VA retinoid production from dietary ß-carotene (BC). ISX-deficient dams were fed a VA-sufficient or a BC-enriched diet during the last week of gestation and the whole lactation period. Total retinol levels in milk and weanling livers were 2 to 2.5-fold higher in the offspring of BC-fed dams (BC offspring), indicating increased VA supplies during late gestation and lactation. The corresponding VAS and BC offspring (males and females) were compared at weaning and adulthood after being fed either a standard or high-fat diet (HFD) with regular VA content for 13 weeks from weaning. HFD-induced increases in adiposity metrics, such as fat depot mass and adipocyte diameter, were more pronounced in males than females and were attenuated or suppressed in the BC offspring. Notably, the BC offspring were protected from HFD-induced increases in circulating triacylglycerol levels and hepatic steatosis. These protective effects were associated with reduced food efficiency, enhanced capacity for thermogenesis and mitochondrial oxidative metabolism in adipose tissues, and increased adipocyte hyperplasia rather than hypertrophy in the BC offspring. In conclusion, maternal VA nutrition influenced by genetics may confer metabolic benefits to the offspring, with mild increases in late gestation and lactation protecting against obesity and metabolic dysregulation in adulthood.

Clinical algorithms for management of fetal heart rate abnormalities during labour.

OBJECTIVE: To construct algorithms with a sequential decision analysis pathway for monitoring of the fetal heart rate and managing fetal heart rate bradycardia, late decelerations and tachycardia during labour. POPULATION: Low-risk pregnant women in labour with singleton cephalic term pregnancies. SETTING: Institutional births in low- and middle-income countries. SEARCH STRATEGY: We sought relevant published clinical algorithms, guidelines and randomised trials/reviews by searching the Cochrane Library, PubMed and Google on the terms: "fetal AND heart AND rate AND algorithm AND (labour OR intrapartum)", up to March 2020. CASE SCENARIOS: The two scenarios included were fetal heart rate bradycardia or late decelerations (potentially related to uterine rupture, placental abruption, cord prolapse, maternal hypotension, uterine hyperstimulation or unexplained) and fetal heart rate tachycardia (potentially related to maternal hyperthermia, infection, dehydration or unexplained). The algorithms provide pathways for definition, assessment, diagnosis, interventions to correct the abnormalities and ongoing monitoring leading to mode of birth, and linking to other algorithms in the series. CONCLUSIONS: The algorithms provide a framework for monitoring and managing fetal heart rate bradycardia, late decelerations and tachycardia during labour. We emphasise the inherent diagnostic inaccuracy of fetal heart rate monitoring, the tendency to over-diagnose fetal compromise, the need to consider fetal heart rate information in the context of other clinical features and the need to engage in informed, shared, family-centred decision-making. We note the need for further research on methods of fetal assessment during labour including clinical fetal arousal testing and the rapid biophysical profile test. TWEETABLE ABSTRACT: Decision analysis algorithms for fetal bradycardia, late decelerations and tachycardia highlight diagnostic limitations.

Constructing evidence-based clinical intrapartum care algorithms for decision-support tools.

AIM: To describe standardised iterative methods used by a multidisciplinary group to develop evidence-based clinical intrapartum care algorithms for the management of uneventful and complicated labours. POPULATION: Singleton, term pregnancies considered to be at low risk of developing complications at admission to the birthing facility. SETTING: Health facilities in low- and middle-income countries. SEARCH STRATEGY: Literature reviews were conducted to identify standardised methods for algorithm development and examples from other fields, and evidence and guidelines for intrapartum care. Searches for different algorithm topics were last updated between January and October 2020 and included a combination of terms such as 'labour', 'intrapartum', 'algorithms' and specific topic terms, using Cochrane Library and MEDLINE/PubMED, CINAHL, National Guidelines Clearinghouse and Google. CASE SCENARIOS: Nine algorithm topics were identified for monitoring and management of uncomplicated labour and childbirth, identification and management of abnormalities of fetal heart rate, liquor, uterine contractions, labour progress, maternal pulse and blood pressure, temperature, urine and complicated third stage of labour. Each topic included between two and four case scenarios covering most common deviations, severity of related complications or critical clinical outcomes. CONCLUSIONS: Intrapartum care algorithms provide a framework for monitoring women, and identifying and managing complications during labour and childbirth. These algorithms will support implementation of WHO recommendations and facilitate the development by stakeholders of evidence-based, up to date, paper-based or digital reminders and decision-support tools. The algorithms need to be field tested and may need to be adapted to specific contexts. TWEETABLE ABSTRACT: Evidence-based intrapartum care clinical algorithms for a safe and positive childbirth experience.

Mechanistic aspects of carotenoid health benefits - where are we now?

Dietary intake and tissue levels of carotenoids have been associated with a reduced risk of several chronic diseases, including cardiovascular diseases, type 2 diabetes, obesity, brain-related diseases and some types of cancer. However, intervention trials with isolated carotenoid supplements have mostly failed to confirm the postulated health benefits. It has thereby been speculated that dosing, matrix and synergistic effects, as well as underlying health and the individual nutritional status plus genetic background do play a role. It appears that our knowledge on carotenoid-mediated health benefits may still be incomplete, as the underlying mechanisms of action are poorly understood in relation to human relevance. Antioxidant mechanisms - direct or via transcription factors such as NRF2 and NF-κB - and activation of nuclear hormone receptor pathways such as of RAR, RXR or also PPARs, via carotenoid metabolites, are the basic principles which we try to connect with carotenoid-transmitted health benefits as exemplified with described common diseases including obesity/diabetes and cancer. Depending on the targeted diseases, single or multiple mechanisms of actions may play a role. In this review and position paper, we try to highlight our present knowledge on carotenoid metabolism and mechanisms translatable into health benefits related to several chronic diseases.

Development of the FAST-M maternal sepsis bundle for use in low-resource settings: a modified Delphi process.

OBJECTIVE: To develop a sepsis care bundle for the initial management of maternal sepsis in low resource settings. DESIGN: Modified Delphi process. SETTING: Participants from 34 countries. POPULATION: Healthcare practitioners working in low resource settings (n = 143; 34 countries), members of an expert panel (n = 11) and consultation with the World Health Organization Global Maternal and Neonatal Sepsis Initiative technical working group. METHODS: We reviewed the literature to identify all potential interventions and practices around the initial management of sepsis that could be bundled together. A modified Delphi process, using an online questionnaire and in-person meetings, was then undertaken to gain consensus on bundle items. Participants ranked potential bundle items in terms of perceived importance and feasibility, considering their use in both hospitals and health centres. Findings from the healthcare practitioners were then triangulated with those of the experts. MAIN OUTCOME MEASURE: Consensus on bundle items. RESULTS: Consensus was reached after three consultation rounds, with the same items deemed most important and feasible by both the healthcare practitioners and expert panel. Final bundle items selected were: (1) Fluids, (2) Antibiotics, (3) Source identification and control, (4) Transfer (to appropriate higher-level care) and (5) Monitoring (of both mother and neonate as appropriate). The bundle was given the acronym 'FAST-M'. CONCLUSION: A clinically relevant maternal sepsis bundle for low resource settings has been developed by international consensus. TWEETABLE ABSTRACT: A maternal sepsis bundle for low resource settings has been developed by international consensus.

Diagnostic accuracy of the partograph alert and action lines to predict adverse birth outcomes: a systematic review.

BACKGROUND: There are questions about the use of the 'one-centimetre per hour rule' as a valid benchmark for assessing the adequacy of labour progress. OBJECTIVES: To determine the accuracy of the alert (1-cm/hour) and action lines of the cervicograph in the partograph to predict adverse birth outcomes among women in first stage of labour. SEARCH STRATEGY: PubMed, EMBASE, CINAHL, POPLINE, Global Health Library, and reference lists of eligible studies. SELECTION CRITERIA: Observational studies and other study designs reporting data on the correlation between the alert line status of women in labour and the occurrence of adverse birth outcomes. DATA COLLECTION AND ANALYSIS: Two reviewers at a time independently identified eligible studies and independently abstracted data including population characteristics and maternal and perinatal outcomes. MAIN RESULTS: Thirteen studies in which 20 471 women participated were included in the review. The percentage of women crossing the alert line varied from 8 to 76% for all maternal or perinatal outcomes. No study showed a robust diagnostic test accuracy profile for any of the selected outcomes. CONCLUSIONS: This systematic review does not support the use of the cervical dilatation over time (at a threshold of 1 cm/h during active first stage) to identify women at risk of adverse birth outcomes. TWEETABLE ABSTRACT: Alert line of partograph does not identify women at risk of adverse birth outcomes.

Retinoic Acid Increases Fatty Acid Oxidation and Irisin Expression in Skeletal Muscle Cells and Impacts Irisin In Vivo.

BACKGROUND/AIMS: All-trans retinoic acid (ATRA) has protective effects against obesity and metabolic syndrome. We here aimed to gain further insight into the interaction of ATRA with skeletal muscle metabolism and secretory activity as important players in metabolic health. METHODS: Cultured murine C2C12 myocytes were used to study direct effects of ATRA on cellular fatty acid oxidation (FAO) rate (using radioactively-labelled palmitate), glucose uptake (using radioactively-labelled 2-deoxy-D-glucose), triacylglycerol levels (by an enzymatic method), and the expression of genes related to FAO and glucose utilization (by RT-real time PCR). We also studied selected myokine production (using ELISA and immunohistochemistry) in ATRA-treated myocytes and intact mice. RESULTS: Exposure of C2C12 myocytes to ATRA led to increased fatty acid consumption and decreased cellular triacylglycerol levels without affecting glucose uptake, and induced the expression of the myokine irisin at the mRNA and secreted protein level in a dose-response manner. ATRA stimulatory effects on FAO-related genes and the Fndc5 gene (encoding irisin) were reproduced by agonists of peroxisome proliferator-activated receptor ß/δ and retinoid X receptors, but not of retinoic acid receptors, and were partially blocked by an AMP-dependent protein kinase inhibitor. Circulating irisin levels were increased by 5-fold in ATRA-treated mice, linked to increased Fndc5 transcription in liver and adipose tissues, rather than skeletal muscle. Immunohistochemistry analysis of FNDC5 suggested that ATRA treatment enhances the release of FNDC5/irisin from skeletal muscle and the liver and its accumulation in interscapular brown and inguinal white adipose depots. CONCLUSION: These results provide new mechanistic insights on how ATRA globally stimulates FAO and enhances irisin secretion, thereby contributing to leaning effects and improved metabolic status.

Dietary vitamin A impacts DNA methylation patterns of adipogenesis-related genes in suckling rats.

We previously showed that vitamin A supplementation in early life impacts white adipose tissue (WAT) biology. We here studied the vitamin's effects on DNA methylation of genes crucial for WAT cell development, determination and metabolism. CpG promoter methylation and mRNA expression of Pparg, Zfp423, Pcna, and Rbp4 was compared in inguinal WAT of 21-day-old rats supplemented during the suckling period with vehicle (controls) or an emulsion of vitamin A as retinyl ester (RE) or ß-carotene (BC). The methylation profile of promoters was affected by vitamin A supplementation with pronounced differences between the RE and BC groups. In the RE group, hypermethylation of the Rbp4 (at multiple CpGs) and the Pparg2 (at a specific CpG) promoters and hypomethylation of the Pcna promoter (at multiple CpGs) was observed, together with inverse changes in gene expression levels. In the BC group, hypomethylation of the Rbp4 and hypermethylation of the Pcna promoter at distinct CpGs was observed, with no effects on gene expression. In both supplemention groups, hypomethylation and increased expression was found for Zfp423. Thus, modest vitamin A supplementation in early postnatal life impacts methylation marks in developing WAT. Differential epigenetic effects of RE and BC in early life may affect adipose tissue programming activity.

Cervical dilatation patterns of 'low-risk' women with spontaneous labour and normal perinatal outcomes: a systematic review.

BACKGROUND: The call for women-centred approaches to reduce labour interventions, particularly primary caesarean section, has renewed an interest in gaining a better understanding of natural labour progression. OBJECTIVE: To synthesise available data on the cervical dilatation patterns during spontaneous labour of 'low-risk' women with normal perinatal outcomes. SEARCH STRATEGY: PubMed, EMBASE, CINAHL, POPLINE, Global Health Library, and reference lists of eligible studies. SELECTION CRITERIA: Observational studies and other study designs. DATA COLLECTION AND ANALYSIS: Two authors extracted data on: maternal characteristics; labour interventions; the duration of labour centimetre by centimetre; and the duration of labour from dilatation at admission through to 10 cm. We pooled data across studies using weighted medians and employed the Bootstrap-t method to generate the corresponding confidence bounds. MAIN RESULTS: Seven observational studies describing labour patterns for 99 971 women met our inclusion criteria. The median time to advance by 1 cm in nulliparous women was longer than 1 hour until a dilatation of 5 cm was reached, with markedly rapid progress after 6 cm. Similar labour progression patterns were observed in parous women. The 95th percentiles for both parity groups suggest that it was not uncommon for some women to reach 10 cm, despite dilatation rates that were much slower than the 1-cm/hour threshold for most part of their first stage of labours. CONCLUSION: An expectation of a minimum cervical dilatation threshold of 1 cm/hour throughout the first stage of labour is unrealistic for most healthy nulliparous and parous women. Our findings call into question the universal application of clinical standards that are conceptually based on an expectation of linear labour progress in all women. FUNDING: UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), Department of Reproductive Health and Research, World Health Organization, and the United States Agency for International Development (USAID). TWEETABLE ABSTRACT: Cervical dilatation threshold of 1 cm/hour throughout labour is unrealistic for most women, regardless of parity.

Comparison of total, free and bioavailable 25-OH vitamin D determinations to evaluate its biological activity in healthy adults: the LabOscat study.

Determination of different forms of 25-OHD (total, free and bioavailable) in healthy young women does not offer additional advantages over standard 25-OHDT for evaluating vitamin D deficiency. In these subjects 25-OHDT values <15 ng/ml would be more appropriate for defining this deficiency. INTRODUCTION: Determination of 25-OH vitamin D serum levels (25-OHD) constitutes the method of choice for evaluating vitamin D deficiency. However, vitamin D-binding protein (DBP) may modulate its bioavailability thereby affecting correct evaluation of 25-OHD status. We analysed the impact of the determination of 25-OHD (total, free and bioavailable) on the evaluation its biologic activity (estimated by serum PTH determination) in healthy young women. METHODS: 173 premenopausal women (aged 35-45 yrs.) were included. We analysed serum values of total 25-OHD (25-OHDT), DBP, albumin, PTH and bone formation (PINP,OC) and resorption (NTx,CTx) markers. Free(25-OHDF) and bioavailable (25-OHDB) serum 25-OHD levels were estimated by DBP and albumin determinations and also directly by ELISA (25-OHDF-2). We analysed threshold PTH values for the different forms of 25-OHD and the correlations and differences according to 25-OHDT levels <20 ng/ml. RESULTS: 62% of subjects had 25-OHD values <20 ng/ml and also had significantly lower 25-OHDF and 25-OHDB values, with no significant differences in bone markers and PTH values. The PTH threshold value was similar for all forms of 25-OHD (∼70 pg/ml). Women with PTH values >70 had lower 25-OHDT (15.4 ± 1.4 vs. 18.3 ± 2.7, p < 0.05) and 25OHDB values (1.7 ± 0.2 vs. 2.2 ± 0.09, p < 0.05). The different forms of 25OHD were significantly intercorrelated, with marginal correlations between PTH and 25-OHDT (r = -0.136, p = 0.082). CONCLUSIONS: Determination of different forms of 25-OHD in healthy young women does not offer additional advantages over standard 25-OHDT for evaluating vitamin D deficiency. In these subjects 25-OHDT values <15 ng/ml would be more appropriate for defining this deficiency.

Changes in management policies for extremely preterm births and neonatal outcomes from 2003 to 2012: two population-based studies in ten European regions.

OBJECTIVE: To investigate changes in maternity and neonatal unit policies towards extremely preterm infants (EPTIs) between 2003 and 2012, and concurrent trends in their mortality and morbidity in ten European regions. DESIGN: Population-based cohort studies in 2003 (MOSAIC study) and 2011/2012 (EPICE study) and questionnaires from hospitals. SETTING: 70 hospitals in ten European regions. POPULATION: Infants born at <27 weeks of gestational age (GA) in hospitals participating in both the MOSAIC and EPICE studies (1240 in 2003, 1293 in 2011/2012). METHODS: We used McNemar's Chi2 test, paired t-tests and conditional logistic regression for comparisons over time. MAIN OUTCOMES MEASURES: Reported policies, mortality and morbidity of EPTIs. RESULTS: The lowest GA at which maternity units reported performing a caesarean section for acute distress of a singleton non-malformed fetus decreased from an average of 24.7 to 24.1 weeks (P < 0.01) when parents were in favour of active management, and 26.1 to 25.2 weeks (P = 0.01) when parents were against. Units reported that neonatologists were called more often for spontaneous deliveries starting at 22 weeks GA in 2012 and more often made decisions about active resuscitation alone, rather than in multidisciplinary teams. In-hospital mortality after live birth for EPTIs decreased from 50% to 42% (P < 0.01). Units reporting more active management in 2012 than 2003 had higher mortality in 2003 (55% versus 43%; P < 0.01) and experienced larger declines (55 to 44%; P < 0.001) than units where policies stayed the same (43 to 37%; P = 0.1). CONCLUSIONS: European hospitals reporting changes in management policies experienced larger survival gains for EPTIs. TWEETABLE ABSTRACT: Changes in reported policies for management of extremely preterm births were related to mortality declines.

EARLY-ESLI study: Long-term experience with eslicarbazepine acetate after first monotherapy failure.

PURPOSE: Evaluate real-life experience with eslicarbazepine acetate (ESL) after first monotherapy failure in a large series of patients with focal epilepsy. METHOD: Multicentre, retrospective, 1-year, observational study in patients older than 18 years, with focal epilepsy, who had failed first antiepileptic drug monotherapy and who received ESL. Data from clinical records were analysed at baseline, 3, 6 and 12 months to assess effectiveness and tolerability. RESULTS: Eslicarbazepine acetate was initiated in 253 patients. The 1-year retention rate was 92.9%, and the final median dose of ESL was 800 mg. At 12 months, 62.3% of patients had been seizure free for 6 months; 37.3% had been seizure free for 1 year. During follow-up, 31.6% of the patients reported ESL-related adverse events (AEs), most commonly somnolence (8.7%) and dizziness (5.1%), and 3.6% discontinued due to AEs. Hyponatraemia was observed in seven patients (2.8%). After starting ESL, 137 patients (54.2%) withdrew the prior monotherapy and converted to ESL monotherapy; 75.9% were seizure free, 87.6% were responders, 4.4% worsened, and 23.4% reported ESL-related AEs. CONCLUSION: Use of ESL after first monotherapy failure was associated with an optimal seizure control and tolerability profile. Over half of patients were converted to ESL monotherapy during follow-up.

Carotenoids in Adipose Tissue Biology and Obesity.

Cell, animal and human studies dealing with carotenoids and carotenoid derivatives as nutritional regulators of adipose tissue biology with implications for the etiology and management of obesity and obesity-related metabolic diseases are reviewed. Most studied carotenoids in this context are ß-carotene, cryptoxanthin, astaxanthin and fucoxanthin, together with ß-carotene-derived retinoids and some other apocarotenoids. Studies indicate an impact of these compounds on essential aspects of adipose tissue biology including the control of adipocyte differentiation (adipogenesis), adipocyte metabolism, oxidative stress and the production of adipose tissue-derived regulatory signals and inflammatory mediators. Specific carotenoids and carotenoid derivatives restrain adipogenesis and adipocyte hypertrophy while enhancing fat oxidation and energy dissipation in brown and white adipocytes, and counteract obesity in animal models. Intake, blood levels and adipocyte content of carotenoids are reduced in human obesity. Specifically designed human intervention studies in the field, though still sparse, indicate a beneficial effect of carotenoid supplementation in the accrual of abdominal adiposity. In summary, studies support a role of specific carotenoids and carotenoid derivatives in the prevention of excess adiposity, and suggest that carotenoid requirements may be dependent on body composition.

Cell-Autonomous Brown-Like Adipogenesis of Preadipocytes From Retinoblastoma Haploinsufficient Mice.

Mechanisms behind the emergence of brown adipocyte-like (brite or beige) adipocytes within white adipose tissue (WAT) are of interest. Retinoblastoma protein gene (Rb) haploinsufficiency associates in mice with improved metabolic regulation linked to a greater capacity for fatty acid oxidation and thermogenesis in WAT. We aimed to explain a feasible mechanism of WAT-to-BAT remodeling in this model. Differentiated primary adipocytes and Sca1-positive preadipocytes derived from adipose depots of Rb(+/-) mice and wild-type siblings were compared. Primary white Rb(+/-) adipocytes displayed under basal conditions increased glucose uptake and an enhanced expression of brown adipocyte-related genes (Pparg, Ppargc1a, Ppargc1b, Prdm16, Cpt1b) but not of purported beige/brite transcriptional markers (Cd137, Tmem26, Tbx1, Slc27a1, Hoxc9, Shox2). Lack of induction of beige markers phenocopied results in WAT of adult Rb(+/-) mice. Flow cytometry analysis evidenced an increased number of preadipocytes in WAT depots of Rb(+/-) mice. Sca1(+) preadipocytes from WAT of Rb(+/-) mice displayed increased gene expression of several transcription factors common to the brown and beige adipogenic programs (Prdm16, Pparg, Ppargc1a) and of receptors of bone morphogenetic proteins (BMPs); however, among the recently proposed beige markers, only Tbx1 was upregulated. Adult Rb(+/-) mice had increased circulating levels of BMP7. These results indicate that preadipose cells resident in WAT depots of Rb(+/-) mice retain an increased capacity for brown-like adipogenesis that appears to be different from beige adipogenesis, and suggest that the contribution of these precursors to the Rb(+/-) adipose phenotype is driven, at least in part, by interaction with BMP7 pathways. J. Cell. Physiol. 231: 1941-1952, 2016. © 2016 Wiley Periodicals, Inc.

Retinoblastoma Protein Knockdown Favors Oxidative Metabolism and Glucose and Fatty Acid Disposal in Muscle Cells.

Deficiency in the retinoblastoma protein (Rb) favors leanness and a healthy metabolic profile in mice largely attributed to activation of oxidative metabolism in white and brown adipose tissues. Less is known about Rb modulation of skeletal muscle metabolism. This was studied here by transiently knocking down Rb expression in differentiated C2C12 myotubes using small interfering RNAs. Compared with control cells transfected with non-targeting RNAs, myotubes silenced for Rb (by 80-90%) had increased expression of genes related to fatty acid uptake and oxidation such as Cd36 and Cpt1b (by 61% and 42%, respectively), increased Mitofusin 2 protein content (∼2.5-fold increase), increased mitochondrial to nuclear DNA ratio (by 48%), increased oxygen consumption (by 65%) and decreased intracellular lipid accumulation. Rb silenced myotubes also displayed up-regulated levels of glucose transporter type 4 expression (∼5-fold increase), increased basal glucose uptake, and enhanced insulin-induced Akt phosphorylation. Interestingly, exercise in mice led to increased Rb phosphorylation (inactivation) in skeletal muscle as evidenced by immunohistochemistry analysis. In conclusion, the silencing of Rb enhances mitochondrial oxidative metabolism and fatty acid and glucose disposal in skeletal myotubes, and changes in Rb status may contribute to muscle physiological adaptation to exercise.

All-trans retinoic acid induces oxidative phosphorylation and mitochondria biogenesis in adipocytes.

A positive effect of all-trans retinoic acid (ATRA) on white adipose tissue (WAT) oxidative and thermogenic capacity has been described and linked to an in vivo fat-lowering effect of ATRA in mice. However, little is known about the effects of ATRA on mitochondria in white fat. Our objective has been to characterize the effect of ATRA on mitochondria biogenesis and oxidative phosphorylation (OXPHOS) capacity in mature white adipocytes. Transcriptome analysis, oxygraphy, analysis of mitochondrial DNA (mtDNA), and flow cytometry-based analysis of mitochondria density were performed in mature 3T3-L1 adipocytes after 24 h incubation with ATRA (2 µM) or vehicle. Selected genes linked to mitochondria biogenesis and function and mitochondria immunostaining were analyzed in WAT tissues of ATRA-treated as compared with vehicle-treated mice. ATRA upregulated the expression of a large set of genes linked to mtDNA replication and transcription, mitochondrial biogenesis, and OXPHOS in adipocytes, as indicated by transcriptome analysis. Oxygen consumption rate, mtDNA content, and staining of mitochondria were increased in the ATRA-treated adipocytes. Similar results were obtained in WAT depots of ATRA-treated mice. We conclude that ATRA impacts mitochondria in adipocytes, leading to increased OXPHOS capacity and mitochondrial content in these cells.

Improved metabolic regulation is associated with retinoblastoma protein gene haploinsufficiency in mice.

Retinoblastoma protein (pRb) is involved in the control of energy metabolism, and its inactivation protects mice against high-fat diet-induced diabesity. Here, we tested the hypothesis that partial deficiency in the Rb gene could confer metabolic advantages in front of acute challenges to metabolism and as mice age on a regular diet. Rb haploinsufficient (Rb(+/-)) mice and wild-type (WT) littermates were studied from weaning and characterized at 1.5-2.5 mo of age (young adults) and 6-7.5 mo of age (mature adults). Whereas no differences in body weight or composition were observed at young age, mature adult Rb(+/-) mice were leaner than WT littermates, displaying 36% reduced body fat content. At both ages studied, Rb(+/-) mice displayed improved blood lipids, enhanced sensitivity to the blood glucose-lowering effect of insulin and to the anorectic effect of leptin, and a reduced respiratory exchange ratio, indicative of an increased use of fatty acids as a fuel. Insulin sensitivity and oral fat tolerance were better maintained with age in the Rb(+/-) than the WT mice. Mature adult Rb(+/-) mice displayed gene expression changes consistent with increased fatty acid oxidation in white adipose tissue and skeletal muscle and paramount signs of browning in the inguinal white adipose tissue. In conclusion, Rb haploinsufficiency provides metabolic advantages in front of acute metabolic stressors and ameliorates body fat gain and metabolic impairments that normally accompany transition from young to mature adult age.

Synergistic Effects of a Mixture of Glycosaminoglycans to Inhibit Adipogenesis and Enhance Chondrocyte Features in Multipotent Cells.

BACKGROUND/AIMS: Multipotent mesenchymal stem cells affect homeostasis of adipose and joint tissues. Factors influencing their differentiation fate are of interest for both obesity and joint problems. We studied the impact of a mixture of glycosaminoglycans (GAGs) (hyaluronic acid: dermatan sulfate 1:0.25, w/w) used in an oral supplement for joint discomfort (Oralvisc™) on the differentiation fate of multipotent cells. METHODS: Primary mouse embryo fibroblasts (MEFs) were used as a model system. Post-confluent monolayer MEF cultures non-stimulated or hormonally stimulated to adipogenesis were chronically exposed to the GAGs mixture, its individual components or vehicle. The appearance of lipid laden cells, lipid accumulation and expression of selected genes at the mRNA and protein level was assessed. RESULTS: Exposure to the GAGs mixture synergistically suppressed spontaneous adipogenesis and induced the expression of cartilage extracellular matrix proteins, aggrecan core protein, decorin and cartilage oligomeric matrix protein. Hormonally-induced adipogenesis in the presence of the GAGs mixture resulted in decreased adipogenic differentiation, down-regulation of adipogenic/lipogenic factors and genes for insulin resistance-related adipokines (resistin and retinol binding protein 4), and up-regulation of oxidative metabolism-related genes. Adipogenesis in the presence of dermatan sulfate, the minor component of the mixture, was not impaired but resulted in smaller lipid droplets and the induction of a more complete brown adipocyte-related transcriptional program in the cells in the adipose state. CONCLUSIONS: The Oralvisc™ GAGs mixture can tip the adipogenic/chondrogenic fate balance of multipotent cells away from adipogenesis while favoring chondrocyte related gene expression. The mixture and its dermatan sulfate component also have modulatory effects of interest on hormonally-induced adipogenesis and on metabolic and secretory capabilities of adipose cells.

Carotenoids and their conversion products in the control of adipocyte function, adiposity and obesity.

A novel perspective of the function of carotenoids and carotenoid-derived products - including, but not restricted to, the retinoids - is emerging in recent years which connects these compounds to the control of adipocyte biology and body fat accumulation, with implications for the management of obesity, diabetes and cardiovascular disease. Cell and animal studies indicate that carotenoids and carotenoids derivatives can reduce adiposity and impact key aspects of adipose tissue biology including adipocyte differentiation, hypertrophy, capacity for fatty acid oxidation and thermogenesis (including browning of white adipose tissue) and secretory function. Epidemiological studies in humans associate higher dietary intakes and serum levels of carotenoids with decreased adiposity. Specifically designed human intervention studies, though still sparse, indicate a beneficial effect of carotenoid supplementation in the accrual of abdominal adiposity. The objective of this review is to summarize recent findings in this area, place them in physiological contexts, and provide likely regulatory schemes whenever possible. The focus will be on the effects of carotenoids as nutritional regulators of adipose tissue biology and both animal and human studies, which support a role of carotenoids and retinoids in the prevention of abdominal adiposity.