Pericardial fat is a nutritionally regulated depot of brown adipose tissue

Introduction: Obesity and related cardio-metabolic complications have acquired global epidemic proportions. Suboptimal nutritional environment in early life induces adaptations in energy homeostasis, metabolism and adipose tissue development that may confer short-term survival advantages but are detrimental in later life, particularly if nutrient supply is restored. Brown adipose tissue (BAT) has a unique role in energy homeostasis because it can provide a potential compensatory mechanism against excess weight gain via cold or diet-induced adaptive thermogenesis. Brown adipocytes also have a potential role in lipid and glucose metabolism and BAT activation can increase clearance of lipids and glucose from the circulation. Pericardial fat, particularly epicardial adipose tissue (fat present between the myocardium and the visceral layer of the pericardium), is anatomically and clinically related to cardiac morphology and function and is believed to be a metabolically active organ that affects cardiac function and the evolution of cardiac pathologies. High expression of mRNA for uncoupling protein (UCP) 1 in adult human epicardial adipose tissue suggests that this may be a depot of BAT. Hypotheses: In my thesis, I hypothesised that pericardial adipose tissue is a depot of brown fat in humans and sheep. I also hypothesised that suboptimal nutrition in early life will affect adiposity and development of BAT in this depot. Methods: UCP1 mRNA expression and protein abundance and other BAT and white adipose tissue related genes were studied in pericardial adipose tissue. In the first study, pericardial fat was sampled from newborn and 30 day old sheep born to mothers fed with 100% or 60% of their total metabolisable energy (ME) requirement from 110 day gestation to term. In the second study, pericardial fat was sampled from near-term (140 day gestation) fetuses delivered to mothers fed 100% or 60% of total ME requirement from 28 to 80 days and then fed ad libitum. Gene expression was measured by reverse transcription-polymerase chain reaction and protein abundance by Western blotting and immunohistochemistry. To confirm the presence of BAT in the human epicardial fat depot, relative abundance of UCP1 was measured by Western Blotting in epicardial, paracardial, and subcutaneous fat samples taken from adults. In the final study, epicardial fat samples were collected from 63 children (0-18 years of age) undergoing cardiac surgery and gene expression of UCP1 and other BAT and WAT related genes identified by microarray. The presence of UCP1 was confirmed by immunohistochemistry. Results: Pericardial adipose tissue is a depot of BAT in fetal and newborn sheep. Suboptimal maternal nutrition in late gestation reduces the abundance of UCP1 and downregulates other BAT related genes whilst suboptimal maternal nutrition in early-to-mid gestation followed by ad libitum feeding to term, increases adiposity, enhances UCP1 abundance and upregulates genes involved in brown and white adipogenesis. Epicardial fat from newborn infants, children, adolescents and older adults contains UCP1 confirming that it is a BAT depot in humans. UCP1 gene expression in infancy and early childhood in humans is downregulated in children with poor nutritional states. Conclusions: I have shown that adipose tissue depots present around the heart are a repository of brown fat, at least in humans and sheep. In view of the potential role of BAT in regulation of lipid and glucose metabolism, this may have therapeutic implications for treatment of cardiovascular complications of obesity. Suboptimal nutrition in utero and during early life compromises BAT development. Although the exact mechanism of how these changes affect the propensity towards obesity and metabolic dysregulation remains to be elucidated, a reduction in thermogenesis presents a plausible mechanism for the increased metabolic efficiency associated with nutritional deprivation in early life. BAT persists beyond the neonatal period in to adult life and, therefore, presents a potential target for long lasting nutritional manipulations to promote better health

Pericardial fat is a nutritionally regulated depot of brown adipose tissue

Introduction: Obesity and related cardio-metabolic complications have acquired global epidemic proportions. Suboptimal nutritional environment in early life induces adaptations in energy homeostasis, metabolism and adipose tissue development that may confer short-term survival advantages but are detrimental in later life, particularly if nutrient supply is restored. Brown adipose tissue (BAT) has a unique role in energy homeostasis because it can provide a potential compensatory mechanism against excess weight gain via cold or diet-induced adaptive thermogenesis. Brown adipocytes also have a potential role in lipid and glucose metabolism and BAT activation can increase clearance of lipids and glucose from the circulation. Pericardial fat, particularly epicardial adipose tissue (fat present between the myocardium and the visceral layer of the pericardium), is anatomically and clinically related to cardiac morphology and function and is believed to be a metabolically active organ that affects cardiac function and the evolution of cardiac pathologies. High expression of mRNA for uncoupling protein (UCP) 1 in adult human epicardial adipose tissue suggests that this may be a depot of BAT. Hypotheses: In my thesis, I hypothesised that pericardial adipose tissue is a depot of brown fat in humans and sheep. I also hypothesised that suboptimal nutrition in early life will affect adiposity and development of BAT in this depot. Methods: UCP1 mRNA expression and protein abundance and other BAT and white adipose tissue related genes were studied in pericardial adipose tissue. In the first study, pericardial fat was sampled from newborn and 30 day old sheep born to mothers fed with 100% or 60% of their total metabolisable energy (ME) requirement from 110 day gestation to term. In the second study, pericardial fat was sampled from near-term (140 day gestation) fetuses delivered to mothers fed 100% or 60% of total ME requirement from 28 to 80 days and then fed ad libitum. Gene expression was measured by reverse transcription-polymerase chain reaction and protein abundance by Western blotting and immunohistochemistry. To confirm the presence of BAT in the human epicardial fat depot, relative abundance of UCP1 was measured by Western Blotting in epicardial, paracardial, and subcutaneous fat samples taken from adults. In the final study, epicardial fat samples were collected from 63 children (0-18 years of age) undergoing cardiac surgery and gene expression of UCP1 and other BAT and WAT related genes identified by microarray. The presence of UCP1 was confirmed by immunohistochemistry. Results: Pericardial adipose tissue is a depot of BAT in fetal and newborn sheep. Suboptimal maternal nutrition in late gestation reduces the abundance of UCP1 and downregulates other BAT related genes whilst suboptimal maternal nutrition in early-to-mid gestation followed by ad libitum feeding to term, increases adiposity, enhances UCP1 abundance and upregulates genes involved in brown and white adipogenesis. Epicardial fat from newborn infants, children, adolescents and older adults contains UCP1 confirming that it is a BAT depot in humans. UCP1 gene expression in infancy and early childhood in humans is downregulated in children with poor nutritional states. Conclusions: I have shown that adipose tissue depots present around the heart are a repository of brown fat, at least in humans and sheep. In view of the potential role of BAT in regulation of lipid and glucose metabolism, this may have therapeutic implications for treatment of cardiovascular complications of obesity. Suboptimal nutrition in utero and during early life compromises BAT development. Although the exact mechanism of how these changes affect the propensity towards obesity and metabolic dysregulation remains to be elucidated, a reduction in thermogenesis presents a plausible mechanism for the increased metabolic efficiency associated with nutritional deprivation in early life. BAT persists beyond the neonatal period in to adult life and, therefore, presents a potential target for long lasting nutritional manipulations to promote better health

Oropharyngeal colostrum in preventing mortality and morbidity in preterm infants

BackgroundPlacing a small volume of colostrum directly onto the buccal mucosa of preterm infants during the early neonatal period may provide immunological and growth factors that stimulate the immune system and enhance intestinal growth. These benefits could potentially reduce the risk of infection and necrotising enterocolitis (NEC) and improve survival and long‐term outcome. ObjectivesTo determine if early (within the first 48 hours of life) oropharyngeal administration of mother’s own fresh or frozen/thawed colostrum can reduce rates of NEC, late‐onset invasive infection, and/or mortality in preterm infants compared with controls. To assess trials for evidence of safety and harm (e.g. aspiration pneumonia). To compare effects of early oropharyngeal colostrum (OPC) versus no OPC, placebo, late OPC, and nasogastric colostrum. Search methodsWe used the standard search strategy of the Cochrane Neonatal Review Group to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 8), MEDLINE via PubMed (1966 to August 2017), Embase (1980 to August 2017), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL; 1982 to August 2017). We also searched clinical trials registries for ongoing and recently completed trials (clinicaltrials.gov; the World Health Organization International Trials Registry (www.whoint/ictrp/search/en/), and the ISRCTN Registry), conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi‐randomised trials. We performed the last search in August 2017. We contacted trial investigators regarding unpublished studies and data. Selection criteriaWe searched for published and unpublished randomised controlled trials comparing early administration of oropharyngeal colostrum (OPC) versus sham administration of water, oral formula, or donor breast milk, or versus no intervention. We also searched for studies comparing early OPC versus early nasogastric or nasojejunal administration of colostrum. We considered only trials that included preterm infants at < 37 weeks' gestation. We did not limit the review to any particular region or language. Data collection and analysisTwo review authors independently screened retrieved articles for inclusion and independently conducted data extraction, data analysis, and assessments of 'Risk of bias' and quality of evidence. We graded evidence quality using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. We contacted study authors for additional information or clarification when necessary. Main resultsWe included six studies that compared early oropharyngeal colostrum versus water, saline, placebo, or donor, or versus no intervention, enrolling 335 preterm infants with gestational ages ranging from 25 to 32 weeks' gestation and birth weights of 410 to 2500 grams. Researchers found no significant differences between OPC and control for primary outcomes ‐ incidence of NEC (typical risk ratio (RR) 1.42, 95% confidence interval (CI) 0.50 to 4.02; six studies, 335 infants; P = 0.51; I² = 0%; very low‐quality evidence), incidence of late‐onset infection (typical RR 0.86, 95% CI 0.56 to 1.33; six studies, 335 infants; P = 0.50; I² = 0%; very low‐quality evidence), and death before hospital discharge (typical RR 0.76, 95% CI 0.34 to 1.71; six studies, 335 infants; P = 0.51; I² = 0%; very low‐quality evidence). Similarly, meta‐analysis showed no difference in length of hospital stay between OPC and control groups (mean difference (MD) 0.81, 95% CI ‐5.87 to 7.5; four studies, 293 infants; P = 0.65; I² = 49%). Days to full enteral feeds were reduced in the OPC group with MD of ‐2.58 days (95% CI ‐4.01 to ‐1.14; six studies, 335 infants; P = 0.0004; I² = 28%; very low‐quality evidence). The effect of OPC was uncertain because of small sample sizes and imprecision in study results (very low‐quality evidence). No adverse effects were associated with OPC; however, data on adverse effects were insufficient, and no numerical data were available from the included studies. Overall the quality of included studies was low to very low across all outcomes. We downgraded GRADE outcomes because of concerns about allocation concealment and blinding, reporting bias, small sample sizes with few events, and wide confidence intervals. Authors' conclusionsLarge, well‐designed trials would be required to evaluate more precisely and reliably the effects of oropharyngeal colostrum on important outcomes for preterm infants

The placenta, maternal diet and adipose tissue development in the newborn

Background: A majority of adipose tissue present in the newborn possess the unique mitochondrial protein, uncoupling protein (UCP1). It is thus highly metabolically active and capable of producing 300 times more heat per unit mass than any other organ in the body. The extent to which maternal obesity and/or an obesogenic diet impacts on placental function thereby resetting the relative distribution of different types of fat in the fetus is unknown. Summary: Developmentally the majority (if not all) fat in the fetus can be considered as classical brown fat, in which UCP1 is highly abundant. In contrast, beige (or recruitable) fat which possess 90% less UCP1 may only appear after birth, as a majority of fat depots undergo a pronounced transformation that is usually accompanied by the loss of UCP1. The extent to which this process can be modulated in a depot-specific manner and/or changes in the maternal metabolic environment remain unknown. Key Messages: An increased understanding of the mechanism by which offspring born to mothers possess excessive adipose tissue could enable sustainable interventions designed to promote the abundance of UCP1 possessing adipocytes. Ultimately, this would increase their energy expenditure and improve glucose homeostasis in these individuals

Investigating ataxia in childhood

© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ. Ataxia is a common presentation to an acute paediatric unit and it can often be difficult to determine the cause. It is important to distinguish between serious causes, for example, brain tumours and encephalitis, and more benign causes in order to guide investigations and treatment. In this review, we describe the different types of ataxia, the causes associated with them, the examination findings and what investigations to perform in order to make a diagnosis

Education of family members to support weaning to solids and nutrition in infants born preterm (Review) Education of family members to support weaning to solids and nutrition in infants born preterm (Review)

BackgroundWeaning refers to the period of introduction of solid food to complement breast milk or formula milk. Preterm infants are known to acquire extrauterine growth restriction by the time of discharge from neonatal units. Hence, the postdischarge and weaning period are crucial for optimal growth. Optimisation of nutrition during weaning may have long‐term impacts on outcomes in preterm infants. Family members of preterm infants may require nutrition education to promote ideal nutrition practices surrounding weaning in preterm infants who are at high risk of nutritional deficit.ObjectivesTo investigate the role of nutrition education of family members in supporting weaning in preterm infants with respect to their growth and neurodevelopment compared with conventional management.Search methodsWe used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE via PubMed (1966 to 26 June 2018), Embase (1980 to 26 June 2018), and CINAHL (1982 to 26 June 2018). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi‐RCTs.Selection criteriaRCTs and quasi‐RCTs were eligible for inclusion if they examined the effects of nutrition education of family members as compared to conventional management for weaning of preterm infants up to one year of corrected gestational age. We defined prematurity as less than 37 completed weeks of gestation.Data collection and analysisAt least two review authors independently screened potential studies for inclusion and planned to identify, extract data, and assess the quality of eligible studies. We resolved any differences in opinion through discussion with a third review author and consensus among all three review authors.Main resultsNo eligible trials looking at the impact of nutrition education of family members in weaning of preterm infants fulfilled the inclusion criteria of this systematic review. Two studies investigating the ideal timing for weaning in premature infants reported conflicting results,Authors' conclusionsWe were unable to assess the impact of nutrition education of family members in weaning of preterm infants as there were no eligible studies. This may be due to the lack of evidence to determine the ideal weaning strategies for preterm infants with regards to the time of initiating weaning and type of solids to introduce. Trials are needed to assess the many aspects of infant weaning in preterm infants. Long‐term neurodevelopment and metabolic outcomes should also be assessed in addition to growth parameters

Medication errors in infants at home

The study by Solanki and colleagues involved interviewing 166 parents/grandparents at home regarding the medications that had been prescribed at discharge to their infants, by the hospital staff [1]. As part of the study, the parents were also asked to demonstrate how much medicine they would give. With this methodology, Solanki et al. estimated that two out of three of the infants in their study would have experienced medication errors at home. This is an alarmingly high proportion of medication errors. Fortunately, none of the infants experienced significant harm. The authors have suggested that this high rate may be due to lack of parental education and inadequate pre-discharge counselling. The study was performed in Pondicherry in India. It would be wrong, however, to dismiss the relevance of their findings when considering the possibility of medication errors among neonates discharged from centres from high income countries, such as the U.K

Sedation and analgesia from prolonged pain and stress during mechanical ventilation in preterm infants: is dexmedetomidine an alternative to current practice?

Mechanical ventilation is an uncomfortable and potentially painful intervention. Opioids, such as morphine and fentanyl, are used for analgesia and sedation but there is uncertainty whether they reduce pain in mechanically ventilated infants. Moreover, there may be short-term and long-term adverse consequences such as respiratory depression leading to prolonged mechanical ventilation and detrimental long-term neurodevelopmental effects. Despite this, opioids are widely used, possibly due to a lack of alternatives.Dexmedetomidine, a highly selective alpha-2-adrenergic agonist with analgesic and sedative effects, currently approved for adults, has come into use in newborn infants. It provides analgesia and simulates natural sleep with maintenance of spontaneous breathing and upper airway tone. Although data on pharmacokinetics–pharmacodynamics in preterm infants are scant, observational studies report that using dexmedetomidine in conjunction with opioids/benzodiazepines or on its own can reduce the cumulative exposure to opioids/benzodiazepines. As it does not cause respiratory depression, dexmedetomidine could enable quicker weaning and extubation. Dexmedetomidine has also been suggested as an adjunct to therapeutic hypothermia in hypoxic ischaemic encephalopathy and others have used it during painful procedures and surgery. Dexmedetomidine infusion can cause bradycardia and hypotension although most report clinically insignificant effects.The increasing number of publications of observational studies and clinical use demonstrates that dexmedetomidine is being used in newborn infants but data on safety and efficacy are scant and not of high quality. Importantly, there are no data on long-term neurodevelopmental impact on preterm or term-born infants. The acceptance of dexmedetomidine in routine clinical practice must be preceded by clinical evidence. We need adequately powered and well-designed randomised controlled trials investigating whether dexmedetomidine alone or with opioids/benzodiazepines in infants on mechanical ventilation reduces the need for opioids/benzodiazepine and improves neurodevelopment at 24 months and later as compared with the use of opioids/benzodiazepines alone