Effects of postnatal growth restriction and subsequent catch-up growth on neurodevelopment and glucose homeostasis in rats

Intertemporal Improvement in Physicians' Perceptions of the Short-Term Adverse Outcomes of Neonatal Pain: Results of a Two-Time-Point National Survey

Pain in early life may seriously impact neonatal outcomes. This study aimed to evaluate whether the perceptions of physicians working in neonatal intensive care units (NICUs) of the short-term adverse outcomes associated with neonatal pain have changed over a 20-year period. Self-administered questionnaires were distributed to 117 and 145 neonatologists, pediatricians, and fellows working in level III NICUs in 2000 (T1) and 2019 (T2), respectively. The questionnaire consisted of four domains, including the central nervous, cardiovascular, and respiratory systems, as well as "other systems" (metabolic/endocrine system, growth, and general condition), with 21 total items overall. Although the proportion of positive (correct) responses to the total and system-specific domain scores was significantly higher at T2 than T1, the knowledge of certain short-term adverse outcomes was suboptimal even at T2. Adjustment for cofactors confirmed the independent association of the survey time-point with the total and system-specific domain scores. Moreover, NICU type was an independent significant factor associated with the adjusted total and central nervous system scores, while young doctors had a better knowledge of adverse cardiovascular effects. Conclusions: The perceptions of NICU physicians concerning the short-term outcomes associated with neonatal pain have significantly improved over the past 20 years, although remaining knowledge gaps mandate ongoing efforts to achieve an improvement in neonatal care.

Upper arm length and knee height are associated with diabetes in the middle-aged and elderly: evidence from the China Health and Retirement Longitudinal Study

OBJECTIVE

To determine if limb lengths, as markers of early life environment, are associated with the risk of diabetes in China.

DESIGN

We performed a cohort analysis using data from the China Health and Retirement Longitudinal Study (CHARLS), and multivariable-adjusted Cox proportional hazard regression models were used to examine the associations between baseline limb lengths and subsequent risk of diabetes.

SETTING

The CHARLS, 2011-2018.

PARTICIPANTS

The study confined the eligible subject to 10 711 adults aged over 45 years from the CHARLS.

RESULTS

During a mean follow-up period of 6·13 years, 1358 cases of incident diabetes were detected. When controlling for potential covariates, upper arm length was inversely related to diabetes (hazard ratio (HR) 0·95, 95 % CI (0·91, 0·99), P = 0·028), and for every 1-cm difference in knee height, the risk of diabetes decreased by about 4 % (HR 0·96, 95 % CI (0·93, 0·99), P = 0·023). The association between upper arm length and diabetes was only significant among females while the association between knee height and diabetes was only significant among males. In analyses stratified by BMI, significant associations between upper arm length/knee height and diabetes only existed among those who were underweight (HR 0·91, 95 % CI (0·83, 1·00), P = 0·049, HR 0·92, 95 % CI (0·86, 0·99), P = 0·031).

CONCLUSIONS

Inverse associations were observed between upper arm length, knee height and the risk for diabetes development in a large Asian population, suggesting early life environment, especially infant nutritional status, may play an important role in the determination of future diabetes risk.

Malnutrition, poor post-natal growth, intestinal dysbiosis and the developing lung

In extremely preterm infants, poor post-natal growth, intestinal dysbiosis and bronchopulmonary dysplasia are common, and each is associated with long-term complications. The central hypothesis that this review will address is that these three common conditions are interrelated. Challenges to studying this hypothesis include the understanding that malnutrition and poor post-natal growth are not synonymous and that there is not agreement on what constitutes a normal intestinal microbiota in this evolutionarily new population. If this hypothesis is supported, further study of whether "correcting" intestinal dysbiosis in extremely preterm infants reduces postnatal growth restriction and/or bronchopulmonary dysplasia is indicated.

Early Neonatal Pain-A Review of Clinical and Experimental Implications on Painful Conditions Later in Life

Modern health care has brought our society innumerable benefits but has also introduced the experience of pain very early in life. For example, it is now routine care for newborns to receive various injections or have blood drawn within 24 h of life. For infants who are sick or premature, the pain experiences inherent in the required medical care are frequent and often severe, with neonates requiring intensive care admission encountering approximately fourteen painful procedures daily in the hospital. Given that much of the world has seen a steady increase in preterm births for the last several decades, an ever-growing number of babies experience multiple painful events before even leaving the hospital. These noxious events occur during a critical period of neurodevelopment when the nervous system is very vulnerable due to immaturity and neuroplasticity. Here, we provide a narrative review of the literature pertaining to the idea that early life pain has significant long-term effects on neurosensory, cognition, behavior, pain processing, and health outcomes that persist into childhood and even adulthood. We refer to clinical and pre-clinical studies investigating how early life pain impacts acute pain later in life, focusing on animal model correlates that have been used to better understand this relationship. Current knowledge around the proposed underlying mechanisms responsible for the long-lasting consequences of neonatal pain, its neurobiological and behavioral effects, and its influence on later pain states are discussed. We conclude by highlighting that another important consequence of early life pain may be the impact it has on later chronic pain states-an area of research that has received little attention.

The developing gut-lung axis: postnatal growth restriction, intestinal dysbiosis, and pulmonary hypertension in a rodent model

BACKGROUND

Postnatal growth restriction (PNGR) in premature infants increases risk of pulmonary hypertension (PH). In a rodent model, PNGR causes PH, while combining PNGR and hyperoxia increases PH severity. We hypothesized that PNGR causes intestinal dysbiosis and that treatment with a probiotic attenuates PNGR-associated PH.

METHOD

Pups were randomized at birth to room air or 75% oxygen (hyperoxia), to normal milk intake (10 pups/dam) or PNGR (17 pups/dam), and to probiotic Lactobacillus reuteri DSM 17938 or phosphate-buffered saline. After 14 days, PH was assessed by echocardiography and right ventricular hypertrophy (RVH) was assessed by Fulton's index (right ventricular weight/left ventricle + septal weight). The small bowel and cecum were analyzed by high-throughput 16S ribosomal RNA gene sequencing.

RESULTS

PNGR with or without hyperoxia (but not hyperoxia alone) altered the microbiota of the distal small bowel and cecum. Treatment with DSM 17938 attenuated PH and RVH in pups with PNGR, but not hyperoxia alone. DSM 17938 treatment decreased α-diversity. The intestinal microbiota differed based on oxygen exposure, litter size, and probiotic treatment.

CONCLUSION

PNGR causes intestinal dysbiosis and PH. Treatment with DSM 17938 prevents PNGR-associated RVH and PH. Changes in the developing intestine and intestinal microbiota impact the developing lung vasculature and RV.

Transgenerational Obesity and Alteration of ARHGEF11 in the Rat Liver Induced by Intrauterine Hyperglycemia

It is understood that intrauterine hyperglycemia increases the risk of obesity and diabetes in offspring of consecutive generations but its mechanisms remain obscure. This study is aimed at establishing an intrauterine hyperglycemia rat model to investigate the growth and glycolipid metabolic characteristics in transgenerational offspring and discuss the effects of Rho guanine nucleotide exchange factor 11 (ARHGEF11) and the PI3K/AKT signaling pathway in offspring development. The severe intrauterine hyperglycemia rat model was caused by STZ injection before mating, while offspring development and glycolipid metabolism were observed for the following two generations. The expression of ARHGEF11, ROCK1, PI3K, and AKT was tested in the liver and muscle tissue of F2 offspring. The results showed severe growth restriction in F1 offspring and obesity, fatty liver, and insulin resistance in female F2 offspring, especially the offspring of female intrauterine hyperglycemia-exposed parents (F2G♀C♂) and both (F2G♀G♂). The expression of ARHGEF11 and ROCK1 was significantly elevated; PI3K and phosphorylation of AKT were significantly decreased in liver tissues of F2G♀C♂ and F2G♀G♂. Our study revealed that intrauterine hyperglycemia could cause obesity and abnormal glycolipid metabolism in female transgenerational offspring; the programming effect of the intrauterine environment could cause a more obvious phenotype in the maternal line. Further exploration suggested that increased expression of ARHGEF11 and ROCK1 and the decreased expression of PI3K and phosphorylation of AKT in the liver could be responsible for the abnormal development in F2 offspring.

Somatic growth and the risks of bronchopulmonary dysplasia and pulmonary hypertension: connecting epidemiology and physiology 1

In the premature infant, poor growth in utero (fetal growth restriction) and in the first weeks of life (postnatal growth restriction) are associated with increased risk for bronchopulmonary dysplasia and pulmonary hypertension. In this review, we summarize the epidemiologic data supporting these associations, present a novel rodent model of postnatal growth restriction, and review 5 promising mechanisms by which poor nutrition may affect the developing lung. These observations support the hypothesis that nutritional and (or) pharmacologic interventions early in life may be able to decrease risk of the pulmonary complications of extreme prematurity.

How Much Nutrition for How Much Growth?

BACKGROUND/AIMS

Increasing agreement exists about the use of length-for-age as the indicator of choice in monitoring the long-term impact of chronic nutritional deficiency. Yet, already shortly after World War I, a causal link between nutrition and growth was questioned. Also, modern meta-analyses of controlled nutrition intervention studies show that the net effect of nutrition on body height is small. Broad evidence obtained from historic observations on human starvation made since the 19th century questions an obligatory association between nutrition and growth. Many additional explanations for the apparent shortness of people from developing countries have been published since, focusing on genetic factors, environment, economy, epigenetics, and, recently, psychosocial factors, such as strategic growth adjustments suggesting stature to be a social signal.

CONCLUSION

The marked variability in average population height of up to 20 cm within a few generations complicates the use of normative growth charts, even though they have been widely propagated. We support the concept of local growth references, for example using the "Synthetic Growth References" methodology. These references combine local growth information obtained from a given population of interest and common features of human population growth, with LMS values for height, weight, and BMI from birth to maturity.
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[Effect of metformin on insulin resistance during catch-up growth in mice with fetal growth restriction]

OBJECTIVE

To study the efficacy of metformin intervention on insulin resistance during catch-up growth in mice with fetal growth restriction (FGR).

METHODS

Mouse models of FGR were established by low protein diet feeding of the pregnant mice. Both the newborn female mice with FGR and normal control (NC) mice were randomized for feeding with a standard diet (SF) or a high-fat diet (HF) after weaning and treatment with gavage of either metformin or normal saline. The mice were examined for vaginal opening time and the estrous cycle at the age of 8 weeks. At the age of 12 weeks, 6 mice in anestrus from each group were fasted for 12 h for measurement of body weight, height, poundera index (PI), fasting blood glucose (FBG), fasting insulin (Fins), follicle stimulating hormone (FSH) and anti-Mullerian hormone (AMH), and the HOMA-IR was calculated. The reproductive capacity of female mice was assessed by mixing them with male mice at the ratio of 2:1. The 3 × 2 factorial analysis was conducted to determine the interactions between FGR, high-fat feeding and metformin.

RESULTS

Factorial analysis showed that FGR and high-fat feeding had significant effects on the PI index, Fins, HOMA-IR, vaginal opening time, and AMH (P<0.05). Metformin significantly affected the factors related to high-fat feeding including weight, PI, FPG, Fins, HOMA-IR and estrous cycle (P<0.05) and the factors related to FGR with the exception of height and FSH (P<0.05). FGR significantly affected the factors tested except for body weight (P<0.05); high-fat feeding affected all the factors but the FSH (P<0.05); metformin affected all the factors but the height and FSH (P<0.05). In the female mice treated with saline, the pregnancy rates differed significantly between FGR mice with high-fat feeding and control mice with standard feeding, and between FGR mice with standard feeding and high-fat feeding (P<0.05).

CONCLUSION

FGR mice can present with delayed puberty with rare ovulation and adulthood insulin resistance, and high-fat feeding after birth can promote the catch-up growth of FGR mice. Metformin intervention is effective for improving insulin resistance and reproductive-endocrine disorders in FGR mice during catch-up growth.

Effects of iron supplementation on growth, gut microbiota, metabolomics and cognitive development of rat pups

BACKGROUND

Iron deficiency is common during infancy and therefore iron supplementation is recommended. Recent reports suggest that iron supplementation in already iron replete infants may adversely affect growth, cognitive development, and morbidity.

METHODS

Normal and growth restricted rat pups were given iron daily (30 or 150 μg/d) from birth to postnatal day (PD) 20, and followed to PD56. At PD20, hematology, tissue iron, and the hepatic metabolome were measured. The plasma metabolome and colonic microbial ecology were assessed at PD20 and PD56. T-maze (PD35) and passive avoidance (PD40) tests were used to evaluate cognitive development.

RESULTS

Iron supplementation increased iron status in a dose-dependent manner in both groups, but no significant effect of iron on growth was observed. Passive avoidance was significantly lower only in normal rats given high iron compared with controls. In plasma and liver of normal and growth-restricted rats, excess iron increased 3-hydroxybutyrate and decreased several amino acids, urea and myo-inositol. While a profound difference in gut microbiota of normal and growth-restricted rats was observed, with iron supplementation differences in the abundance of strict anaerobes were observed.

CONCLUSION

Excess iron adversely affects cognitive development, which may be a consequence of altered metabolism and/or shifts in gut microbiota.

Postnatal growth restriction augments oxygen-induced pulmonary hypertension in a neonatal rat model of bronchopulmonary dysplasia

BACKGROUND

Prematurity and fetal growth restriction are risk factors for pulmonary hypertension (PH) in infants with bronchopulmonary dysplasia (BPD). Neonatal rats develop PH and vascular remodeling when exposed to hyperoxia. We hypothesize that postnatal growth restriction (PNGR) due to under-nutrition increases the severity of PH induced by hyperoxia in neonatal rats.

METHODS

Pups were randomized at birth to litters maintained in room air or 75% oxygen (hyperoxia), together with litters of normal milk intake (10 pups) or PNGR (17 pups). After 14 d, right ventricular hypertrophy (RVH) was assessed by Fulton's index (right ventricular weight/left ventricular plus septal weight) and PH by echocardiography. Lungs were analyzed by immunohistochemistry, morphometrics, western blotting, and metabolomics.

RESULTS

Hyperoxia and PNGR each significantly increased pulmonary arterial pressure, RVH and pulmonary arterial medial wall thickness, and significantly decreased pulmonary vessel number. These changes were significantly augmented in pups exposed to both insults. Hyperoxia and PNGR both significantly decreased expression of proteins involved in lung development and vasodilation.

CONCLUSION

PNGR induces right ventricular and pulmonary vascular remodeling and augments the effects of oxygen in neonatal rats. This may be a powerful tool to investigate the mechanisms that induce PH in low-birth-weight preterm infants with BPD.

Particulate matter and early childhood body weight

Concerns over adverse effects of air pollution on children's health have been rapidly rising. However, the effects of air pollution on childhood growth remain to be poorly studied. We investigated the association between prenatal and postnatal exposure to PM10 and children's weight from birth to 60months of age. This birth cohort study evaluated 1129 mother-child pairs in South Korea. Children's weight was measured at birth and at six, 12, 24, 36, and 60months. The average levels of children's exposure to particulate matter up to 10μm in diameter (PM10) were estimated during pregnancy and during the period between each visit until 60months of age. Exposure to PM10 during pregnancy lowered children's weight at 12months. PM10 exposure from seven to 12months negatively affected weight at 12, 36, and 60months. Repeated measures of PM10 and weight from 12 to 60months revealed a negative association between postnatal exposure to PM10 and children's weight. Children continuously exposed to a high level of PM10 (>50μg/m(3)) from pregnancy to 24months of age had weight z-scores of 60 that were 0.44 times lower than in children constantly exposed to a lower level of PM10 (≤50μg/m(3)) for the same period. Furthermore, growth was more vulnerable to PM10 exposure in children with birth weight <3.3kg than in children with birth weight >3.3kg. Air pollution may delay growth in early childhood and exposure to air pollution may be more harmful to children when their birth weight is low.

Leg length and type 2 diabetes: what's the link?

PURPOSE OF REVIEW

Human leg length is determined by a complex interplay of genetics and environmental exposures during development, which may be associated with long-term metabolic disease risk. Here, we review recent literature on the link between relative leg length and type 2 diabetes in more and less economically developed societies, wherein the contextual influences on relative leg length are unique. We also hypothesize mechanisms underlying and mediating this association.

RECENT FINDINGS

Evidence from more economically prosperous Western populations and contemporary adult populations in China and Brazil indicates that lower relative leg length is associated with greater risk for impaired glucose homeostasis and type 2 diabetes. In Brazil, this association was stronger among women with early menarche. Although still poorly defined and in need of further research, the potential mechanisms likely involve suboptimal early-life net nutrition that simultaneously leads to retarded growth and impaired glucose regulation. An untested hypothesis is that the association is mediated by differences in skeletal muscle mass.

SUMMARY

Epidemiologic evidence from diverse settings points to humans with shorter legs relative to their stature having higher risk for type 2 diabetes. Although research is needed to test mechanistic hypotheses, the greatest potential for improving public health will come through identification of, and intervention upon, the upstream modifiable determinants of inadequate leg growth.