Minocycline attenuates the bilirubin-induced developmental neurotoxicity through the regulation of innate immunity and oxidative stress in zebrafish embryos.

When liver or intestinal function is impaired, bilirubin accumulates in the body and leads to neonatal jaundice. However, the potential negative effects caused by excessive accumulation of bilirubin such as developmental immunotoxicity and neurotoxicity remain unclear. We used a zebrafish model to establish bilirubin-induced jaundice symptoms and evaluated the toxic effects of bilirubin in aquatic organisms. Firstly, our results suggested that bilirubin exposure markedly decreased the survival rate, induced the developmental toxicity and increased the yellow pigment deposited in the zebrafish tail. Meanwhile, the number of macrophages and neutrophils was substantially reduced in a concentration-dependent manner. Besides, the antioxidant enzyme activities were greatly elevated while the inflammatory genes were significantly decreased after bilirubin exposure. Secondly, transcriptome analysis identified 708 genes were differentially expressed after bilirubin exposure, which animal organ morphogenesis, chemical synaptic transmission, and MAPK / mTOR signaling pathways were significantly enriched. Thirdly, bilirubin exposure leads to a significant decrease in the motility of zebrafish, including a dose-dependent decrease in the travelled distance, movement time, and average velocity. Moreover, the innate immune genes and apoptosis-related genes such as TLR4, NF-κB p65, STAT3 and p53 were elevated at a concentration of 10 µg/mL of bilirubin. Finally, our results further revealed that the anti-inflammatory and neuroprotective minocycline could partially rescue the bilirubin-induced neurobehavioral disorders in zebrafish embryos. In conclusion, our study explored the bilirubin-induced immunotoxicity and neurotoxicity in aquatic organisms, which will provide a theoretical basis for the treatment of neonatal jaundice in clinical practice.

Effect of Epidermal Growth Factor in Human Milk and Maternal Diet on Late-Onset Breast Milk Jaundice: A Case-Control Study in Beijing.

Breast milk is crucial in the development of late-onset breast milk jaundice (BMJ), possibly due to the composition of breast milk and the lactating mother's diet. To explore the possible nutritional pathogenesis of late-onset BMJ, we investigated the lactation diet and collected breast milk by following the 42-day postpartum mother−infants pairs in Beijing and a total of 94 pairs were enrolled. The macronutrient content of breast milk was measured, and the epidermal growth factor (EGF) content in breast milk was determined by ELISA. Data on in-hospital and out-of-hospital breastfeeding, infant growth, jaundice-related vaccination, and puerperium diet were collected. The BMJ group received the second dose of hepatitis B vaccine later than the control group, and the difference was statistically significant (p < 0.001). The EGF concentration in breast milk was lower in the BMJ group than in the control group (p = 0.03). When EGF increased by 1 ng/mL, the transcutaneous bilirubin (TcB) value decreased by 0.33 ng/mL and 0.27 ng/mL before and after the adjustment, respectively. A 1 g increase in oil intake led to a 0.38 ng/mL increase in EGF concentration before the adjustment. With a 1 g increase in oil intake, the TcB value decreased by 0.27 ng/mL before the adjustment, and with a 1 g increase in soybean and soybean product intake, the TcB value decreased by 0.34 ng/mL after the adjustment. Collectively, EGF in breast milk may inhibit the occurrence of late-onset BMJ, and the dietary intake of oil in lactating mothers may affect the level of EGF in breast milk, thus affecting the occurrence of late-onset BMJ. Finally, dietary oil intake may be a protective factor for the occurrence of late-onset BMJ by increasing EGF levels in breast milk.

Vascular network expansion, integrity of blood-brain interfaces, and cerebrospinal fluid cytokine concentration during postnatal development in the normal and jaundiced rat.

BACKGROUND: Severe neonatal jaundice resulting from elevated levels of unconjugated bilirubin in the blood induces dramatic neurological impairment. Central oxidative stress and an inflammatory response have been associated with the pathophysiological mechanism. Cells forming the blood-brain barrier and the choroidal blood-CSF barrier are the first CNS cells exposed to increased plasma levels of unconjugated bilirubin. These barriers are key regulators of brain homeostasis and require active oxidative metabolism to fulfill their protective functions. The choroid plexus-CSF system is involved in neuroinflammatory processes. In this paper, we address the impact of neonatal hyperbilirubinemia on some aspects of brain barriers. We describe physiological changes in the neurovascular network, blood-brain/CSF barriers integrities, and CSF cytokine levels during the postnatal period in normobilirubinemic animals, and analyze these parameters in parallel in Gunn rats that are deficient in bilirubin catabolism and develop postnatal hyperbilirubinemia. METHODS: Gunn rats bearing a mutation in UGT1a genes were used. The neurovascular network was analyzed by immunofluorescence stereomicroscopy. The integrity of the barriers was evaluated by [14C]-sucrose permeability measurement. CSF cytokine levels were measured by multiplex immunoassay. The choroid plexus-CSF system response to an inflammatory challenge was assessed by enumerating CSF leukocytes. RESULTS: In normobilirubinemic animals, the neurovascular network expands postnatally and displays stage-specific regional variations in its complexity. Network expansion is not affected by hyperbilirubinemia. Permeability of the blood-brain and blood-CSF barriers to sucrose decreases between one- and 9-day-old animals, and does not differ between normobilirubinemic and hyperbilirubinemic rats. Cytokine profiles differ between CSF and plasma in all 1-, 9-, and 18-day-old animals. The CSF cytokine profile in 1-day-old animals is markedly different from that established in older animals. Hyperbilirubinemia perturbs these cytokine profiles only to a very limited extent, and reduces CSF immune cell infiltration triggered by systemic exposure to a bacterial lipopeptide. CONCLUSION: The data highlight developmental specificities of the blood-brain barrier organization and of CSF cytokine content. They also indicate that a direct effect of bilirubin on the vascular system organization, brain barriers morphological integrity, and inflammatory response of the choroid plexus-CSF system is not involved in the alteration of brain functions induced by severe neonatal jaundice.

A Neglected and Promising Predictor of Severe Hyperbilirubinemia Due to Hemolysis: Carboxyhemoglobin.

Aims: We investigated the relationship between total serum bilirubin (TSB) and carboxyhemoglobin (COHb) in term neonates with detected and treated hemolysis within a particular time frame with the aim of augmenting the case for early diagnosis and prevention of morbidity in hemolysis. Materials and Methods: The study group comprised term newborns who were above the 95th percentile for TSB, underwent intravenous immunoglobulin (IVIG) or applied total exchange transfusion due to hemolysis. Newborns without hemolysis who were above the 95th TSB percentile and required phototherapy comprised the control group. Results: At a cutoff COHb value of 2.2%, 80.8% sensitivity, 95.5% specificity, 18.1 likelihood ratio, positive predictive value of 94.7%, and negative predictive value of 83.2% were identified. Conclusion: We found that COHb is a sensitive and specific method for detecting hemolysis, and it can be used in the early diagnosis of hemolytic diseases causing early and severe hyperbilirubinemia.

Accuracy of transcutaneous bilirubinometry in the preterm infants: a comprehensive meta-analysis.

BACKGROUND: Transcutaneous bilirubin (TcB) measurement is widely used in term babies. But its effectiveness till debated in preterm infants. So, our objective was to pool data to see the accuracy of transcutaneous bilirubinometry in preterm infants. METHOD: MEDLINE, Embase, Cochrane Library database were searched from 2000 to July 2017. The included studies had compared TcB with total serum bilirubin (TSB) in preterm infants before phototherapy and data were presented as correlation coefficients. Data were extracted by two reviewers and checked for accuracy by the third reviewer. The risk bias assessments were done by an assessment quality assessment of diagnostic accuracy studies tool. Pooled correlation coefficient assed after Fisher's z transformation and then converted to r. RESULTS: We included 28 studies; all those studies reported results as correlation coefficients. In combination of both sternal and forehead site measurement, our pooled estimates of r = 0.82 (95% CI: 0.78-0.85) in random effect and r = 0.803 (95% CI: 0.78-0.81) in fixed effect model. For separate sites of measurement of TcB pooled r for forehead and sternum were comparable, r = 0.82 (95% CI: 0.78-0.85), and pooled correlation coefficient for the two devices JM103 and Bilicheck the estimated pooled r were also comparable (Pooled r = 0.83). CONCLUSION: Our study found that TcB measurement is well related with TSB values and can represent a reliable method for evaluating preterm infants with possible hyperbilirubinemia. Our findings support the use of investigated devices at both forehead and sternum sites in preterm infants.

Newborn Metabolic Profile Associated with Hyperbilirubinemia With and Without Kernicterus.

Our objective was to assess the relationship between hyperbilirubinemia with and without kernicterus and metabolic profile at newborn screening. Included were 1,693,658 infants divided into a training or testing subset in a ratio of 3:1. Forty-two metabolites were analyzed using logistic regression (odds ratios (ORs), area under the receiver operating characteristic curve (AUC), 95% confidence intervals (CIs)). Several metabolite patterns remained consistent across gestational age groups for hyperbilirubinemia without kernicterus. Thyroid stimulating hormone (TSH) and C-18:2 were decreased, whereas tyrosine and C-3 were increased in infants across groupings. Increased C-3 was also observed for kernicterus (OR: 3.17; 95% CI: 1.18-8.53). Thirty-one metabolites were associated with hyperbilirubinemia without kernicterus in the training set. Phenylalanine (OR: 1.91; 95% CI: 1.85-1.97), ornithine (OR: 0.76; 95% 0.74-0.77), and isoleucine + leucine (OR: 0.63; 95% CI: 0.61-0.65) were the most strongly associated. This study showed that newborn metabolic function is associated with hyperbilirubinemia with and without kernicterus.

Breastfeeding during breast milk jaundice - a pathophysiological perspective.

INTRODUCTION: Exclusive breastfeeding for the initial six months of life is crucial and it is recommended . Breast milk jaundice is an innocuous condition that occurs in some healthy, breastfed infants. However, the potential dangers of jaundice in the neonate such as bilirubin induced neuronal pathology, mandates a better understanding of the pathophysiology of breast milk jaundice and the impact of breastfeeding during jaundice. In this context , advice on continued breastfeeding must consider both the benefits of breastfeeding and the possible disadvantages of the jaundice. METHODS: Reviewing literature and integrating relevant information facilitated the appraisal of this important topic. This article reviewed neonatal jaundice, the entry of bilirubin into the immature brain and how breastfeeding may impact jaundice in the neonate. RESULTS: While some substances in breast milk may be responsible for jaundice on the one hand, there is an irrefutable spectrum of advantages conferred by continued breastfeeding, on the other. As the breastfed infant benefits from fewer infections, enhanced organ and physiological barrier maturity, as well as the prospect of genetic modification of certain diseases, these useful actions could also reduce risks of early jaundice and its complications. DISCUSSION: An exciting field for further research, holistic integration of knowledge clarifies both the overall advantages of breastfeeding and wisdom of its continued counsel. In fact, breast milk jaundice may reflect a holistic expression of tissue protection and enhanced neonatal survival.

Meconium microbiome associates with the development of neonatal jaundice.

OBJECTIVE: Neonatal jaundice is a common disease that affects up to 60% of newborns. Gut microbiota mediated the excretion of bilirubin from the human body. However, the relationship between early gut microbiome and development of neonatal jaundice is not fully understood. Here we sought to characterize meconium microbiome of newborns and to clarify its association with risk of neonatal jaundice. METHODS: We conducted a nested case-control study with 301 newborns providing meconium samples from 2014 to 2015. The main outcome was the development of neonatal jaundice at 42 day follow-up. 16S rRNA gene sequencing was performed to profile the meconium microbiome. LEfSe was employed to identify different features between control and case groups. Logistic regression was used to estimate the risk effect of early gut microbiome on neonatal jaundice. RESULTS: Logistic regression models suggested that higher ɑ-diversity was significantly associated with lower risk of jaundice in cesarean infants (OR 0.72, 95% CI 0.52-0.98), but not in infants born naturally. Higher relative abundance of Bifidobacterium pseudolongum in newborn meconium was significantly associated with lower risk of jaundice both in cesarean-born infants and in the total subjects (OR 0.24, 95% CI 0.07-0.68; OR 0.55, 95% CI 0.31-0.95, respectively). Spearman's correlations showed that relative abundance of B. pseudolongum was significantly correlated with ɑ-diversity (P < 0.01). CONCLUSION: Preventive and treatment methods implying early gut microbiome intervention could be promising for the management of neonatal jaundice.

Ursodeoxycholic acid versus phenobarbital for cholestasis in the Neonatal Intensive Care Unit.

BACKGROUND: Although neonates and young infants with cholestasis are commonly treated with either phenobarbital or ursodeoxycholic acid (ursodiol), there is no evidence that phenobarbital is effective for this indication. Our objective was to compare the effectiveness of ursodiol and phenobarbital for the treatment of cholestasis in a diverse NICU population. METHODS: This is a retrospective cohort study including infants with cholestasis who were admitted to a Level IV NICU between January 2010 and December 2015. Drug courses of phenobarbital and ursodiol were identified within the medical record, and medical, demographic, and drug information were extracted. The primary outcome was reduction in direct bilirubin. RESULTS: Sixty-eight infants provided a total of 112 courses of drug therapy for comparison. Diverse medical diagnoses were captured in the patient cohort. Ursodiol was significantly more effective in reducing direct bilirubin than was phenobarbital (- 1.89 vs + 0.76 mg/dL; - 33.33 vs + 13.0 umol/L, p-value 0.03), even after controlling for baseline cholestasis severity, intrauterine growth restriction status, and lipid lowering therapy (- 2.16 vs + 0.27 mg/dl; - 36.94 vs + 4.62 umol/L, p-value 0.03). There was no improvement in direct bilirubin in the majority of infants treated with phenobarbital. CONCLUSIONS: Phenobarbital, as compared to ursodiol, has limited efficacy for the reduction of direct bilirubin in neonates and young infants with cholestasis. Given new data regarding the potential neurotoxicity of phenobarbital in the developing brain, providers may choose to avoid phenobarbital in the treatment of cholestasis in infants.

Management options for cholestatic liver disease in children.

INTRODUCTION: Due to a peculiar age-dependent increased susceptibility, neonatal cholestasis affects the liver of approximately 1 in every 2500 term infants. A high index of suspicion is the key to an early diagnosis, and to implement timely, often life-saving treatments. Even when specific treatment is not available or curative, prompt medical management and optimization of nutrition are of paramount importance to survival and avoidance of complications. Areas covered: The present article will prominently focus on a series of newer diagnostic and therapeutic options of cholestasis in neonates and infants blended with consolidated established paradigms. The overview of strategies for the management reported here is based on a systematic literature search published in English using accessible databases (PubMed, MEDLINE) with the keywords biliary atresia, choleretics and neonatal cholestasis. References lists from retrieved articles were also reviewed. Expert commentary: A large number of uncommon and rare hepatobiliary disorders may present with cholestasis during the neonatal and infantile period. Potentially life-saving disease-specific pharmacological and surgical therapeutic approaches are currently available. Advances in hepatobiliary transport mechanisms have started clarifying fundamental aspects of inherited and acquired cholestasis, laying the foundation for the development of possibly more effective specific therapies.

Auditory toxicity in late preterm and term neonates with severe jaundice.

AIM: Jaundice may cause auditory toxicity (auditory neuropathy and hearing loss). However, total serum bilirubin (TSB) does not discriminate neonates at risk for auditory toxicity. We compared TSB, bilirubin:albumin molar ratio (BAMR), and unbound bilirubin for their association with auditory toxicity in neonates with severe jaundice (TSB ≥342µmol/L, or that met exchange transfusion). METHOD: Neonates greater or equal to 34 weeks gestational age with severe jaundice during the first 2 postnatal weeks were eligible for prospective cohort study, unless they had craniofacial malformations, chromosomal disorders, toxoplasmosis, other infections, rubella, cytomegalovirus, herpes simplex infections, surgery, or family history of congenital deafness. RESULTS: Twenty-eight out of 100 neonates (mean gestational age 37.4wks; 59 males, 41 females) had auditory toxicity. Peak unbound bilirubin, but not peak TSB and BAMR, was associated with auditory toxicity (p<0.05) in neonates with severe (TSB <427.5µmol/L) and extreme hyperbilirubinemia (TSB ≥427.5µmol/L). Area under the receiver operating characteristic curve for unbound bilirubin (0.78) was significantly greater (p=0.03) than TSB (0.54) among neonates with severe but not extreme hyperbilirubinemia. INTERPRETATION: Unbound bilirubin is more strongly associated with auditory toxicity than TSB and/or BAMR in greater or equal to 34 weeks gestational age neonates with severe jaundice. Unbound bilirubin is a better predictor than TSB in neonates with severe hyperbilirubinemia.

A Pilot Metabolic Profiling Study of Patients With Neonatal Jaundice and Response to Phototherapy.

Phototherapy has been widely used in treating neonatal jaundice, but detailed metabonomic profiles of neonatal jaundice patients and response to phototherapy have not been characterized. Our aim was to depict the serum metabolic characteristics of neonatal jaundice patients relative to controls and changes in response to phototherapy. A (1) H nuclear magnetic resonance (NMR)-based metabonomic approach was employed to study the metabolic profiling of serum from healthy infants (n = 25) and from infants with neonatal jaundice (n = 30) pre- and postphototherapy. The acquired data were processed by multivariate principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA). The PLS-DA and OPLS-DA model identified nine metabolites capable of distinguishing patients from controls. In addition, 28 metabolites such as ß-glucose, α-glucose, valine, and pyruvate changed in response to phototherapy. This study offers useful information on metabolic disorders in neonatal jaundice patients and the effects of phototherapy on lipids, amino acid, and energy metabolism.

Biology of Bilirubin Photoisomers.

Phototherapy is the main treatment for neonatal hyperbilirubinemia. In acute treatment of extreme hyperbilirubinemia, intensive phototherapy may have a role in 'detoxifying' the bilirubin molecule to more polar photoisomers, which should be less prone to crossing the blood-brain barrier, providing a 'brain-sparing' effect. This article reviews the biology of bilirubin isomers. Although there is evidence supporting the lower toxicity of bilirubin photoisomers, there are studies showing the opposite. There are methodologic weaknesses in most studies and better-designed experiments are needed. In an infant acutely threatened by bilirubin-induced brain damage, intensified phototherapy should be used expediently and aggressively.

Heliotherapy for Neonatal Hyperbilirubinemia in Southwest, Nigeria: A Baseline Pre-Intervention Study.

BACKGROUND: A novel filtered-sunlight phototherapy (FSPT) device has been demonstrated to be safe and efficacious for treating infants with neonatal jaundice in resource-constrained tropical settings. We set out to provide baseline data for evaluating the clinical impact of this device in a referral pediatric hospital. METHODS: We reviewed the medical records of infants admitted for neonatal hyperbilirubinemia in an inner-city Children's Hospital in Lagos, between January 2012 and December 2014 to determine the pattern, treatment and outcomes during the pre-intervention period. Factors associated with adverse outcomes were identified through multivariable logistic regression. RESULTS: Of the 5,229 neonatal admissions over the period, a total of 1,153 (22.1%) were admitted for neonatal hyperbilirubinemia. Complete records for 1,118 infants were available for analysis. The incidence of acute bilirubin encephalopathy (ABE) and exchange transfusion (ET) were 17.0% (95% CI: 14.9%-19.3%) and 31.5% (95% CI: 28.8%-34.3%) respectively. A total of 61 (5.5%, 95% CI: 4.3%-6.9%) of the jaundiced infants died. Weight on admission, peak total serum bilirubin (TSB), sepsis and exposure to hemolytic products were predictive of ABE, while age on admission, peak TSB, ABO incompatibility and ABE were predictive of ET. Rhesus incompatibility, asphyxia, exposure to hemolytic substances and ABE were associated with elevated mortality risk, while ET was a protective factor. Lack of routine irradiance monitoring and steady energy supply were frequent challenges for conventional blue-light phototherapy. CONCLUSIONS: Severe hyperbilirubinemia is associated with high rates of ABE and ET in this setting, and remains a significant contributor to neonatal admissions and mortality. To be impactful, FSPT, complemented with improved diagnostic facilities, should effectively curtail jaundice-related adverse outcomes in this and comparable settings.

Effects of baby massage on neonatal jaundice in healthy Iranian infants: A pilot study.

OBJECTIVE: To evaluate the effects of baby massage on transcutaneous bilirubin levels and stool frequency of healthy term newborns. METHODS: This Pilot study was conducted on 50 healthy newborns in Valiasr Hospital of IKHC. The infants were randomly allocated to two treatment (massage) and control group. The massage group received massage therapy (according to Touch Therapy) for four days from the first day postnatal while the control group received routine care. Main variable studied were transcutaneous bilirubin level (TCB) and stool frequency which were compared in two groups. RESULTS: There were 50 newborns in the study 25 in each group (50%). There was a significant difference in the TCB levels between two groups (p=0.000) with those in the massage group having lower bilirubin levels. As for the stool frequency there was a significant difference in two groups on the first day showing more defecation in the control group (p=0.042) which on the consequent days was not significant and the frequencies were almost similar. CONCLUSION: Massage group had a lower transcutaneous billirubin levels compared to the control group, thus, these pilot results indicate that massaging the newborns can be accompanied by a lower bilirubin level in the healthy term newborn.

Therapeutic effect of Agaricus brasiliensis on phenylhydrazine-induced neonatal jaundice in rats.

The present study was designed to investigate the effect of Agaricus brasiliensis extract (ABE) on phenylhydrazine-induced neonatal jaundice in rats. Administration of ABE dose-dependently reduced the elevated bilirubin level induced by phenylhydrazine. It can be somewhat supported from the results of in vitro bilirubin degradation experiment. ABE treatment also reduced the total antioxidant status (TAOS), cascade O2(-)/SOD, level of NF-κB protein, and adrenomedullin (AM). Overall, the results of this study demonstrated that Agaricus brasiliensis extract may be beneficial to reducing bilirubin level without causing hepatotoxicity in neonatal jaundice.

End-tidal carbon monoxide as an indicator of the hemolytic rate.

In the first days of life, low grade jaundice is essentially universal. The source of the elevated bilirubin level giving rise to "physiological jaundice of the newborn" is only partly known. We hypothesized that it is, at least in part, the result of active and specific hemolysis involving a physiological mechanism to lower the high fetal hematocrit, appropriate for the relatively low oxygen environment in utero, to a lower level appropriate for the state of oxygen abundance after birth. We tested this by quantifying end tidal carbon monoxide (ETCO) as a marker of the rate of heme metabolism to bilirubin. We found that ETCO values of 20 neonates and children with known hemolytic disorders were higher than 20 age-matched healthy controls (p<0.0001), indicating that this instrumentation recognizes hemolysis in neonates and children. We also found that ETCO reference intervals were indeed higher in healthy neonates during the first three days after birth (5th to 95th percentile reference range, 1.4 to 1.7ppm) than after 1month of age (all ≤1.0ppm, p<0.0001). These results suggest to us that hemolysis is physiological during the first days after birth. The cellular and molecular mechanisms responsible for transient hemolysis after birth are topics of current investigation.

Blood-brain barrier and bilirubin: clinical aspects and experimental data.

The blood-brain barrier (BBB) is a complex and dynamic structure that plays a key role in central nervous system (CNS) homeostasis. It strictly regulates the entrance of molecules into the brain parenchyma and prevents the access of neurotoxins and pathogens while promoting the efflux of several molecules. The brain microvascular endothelial cells are the anatomical basis of the BBB, which has unique characteristics such as the elaborate junctional complexes that nearly obliterate the intercellular space as well as the presence of influx and efflux transporters. Endothelial cells establish important interactions with glial cells, neurons, and perivascular pericytes as well as with the acellular components of the basement membrane, which together constitute the neurovascular unit. BBB disruption has been reported in a wide range of CNS pathologies, with an emerging role in the onset and disease progression. Accordingly, recent studies revealed vascular dysfunction in neonatal jaundice, a common pathology in the early neonatal period affecting 1/10 children presenting values of total bilirubin>17 mg/dL (291 µM). Here we summarize the clinical aspects of moderate to severe neonatal jaundice and provide a comprehensive review of the literature regarding bilirubin-induced neurotoxicity from a vascular-centered approach. The collected evidence place endothelial dysfunction and pericyte demise as key players in the disruption of CNS homeostasis, mainly in cases of lasting hyperbilirubinemia, thus pointing to novel targets to prevent neurological dysfunction due to severe neonatal jaundice.