Melatonin use for neuroprotection in perinatal asphyxia: a randomized controlled pilot study

Neonatal encephalopathy: a systematic review of reported treatment outcomes

BACKGROUND

Neonatal encephalopathy (NE) is a multi-organ condition potentially leading to death or long-term neurodisability. Therapeutic hypothermia is the standard treatment for NE; however, long-term impairments remain common. Studies of new treatments for NE often measure and report different outcomes. Core outcome sets (COSs), a minimum set of outcomes to be measured and reported in all studies for a condition, address this problem. This paper aimed to identify outcomes reported (primary, secondary, adverse events and other reported outcomes) in (1) randomised trials and (2) systematic reviews of randomised trials of interventions for the treatment of NE in the process of developing a COS for interventions for the treatment of NE.

METHODS

We completed a systematic search for outcomes used to evaluate treatments for NE using MEDLINE, Embase, Cochrane CENTRAL, the Cochrane Database of Systematic Reviews and the WHO International Clinical Trials Registry Platform. Two reviewers screened all included articles independently. Outcomes were extracted verbatim, similar outcomes were grouped and outcome domains were developed.

RESULTS

386 outcomes were reported in 116 papers, from 85 studies. Outcomes were categorised into 18 domains. No outcome was reported by all studies, a single study reported 11 outcomes and it was not explicitly stated that outcomes had input from parents.

DISCUSSION

Heterogeneity in reported outcomes means that synthesis of studies evaluating new treatments for NE remains difficult. A COS, that includes parental/family input, is needed to ensure consistency in measuring and reporting outcomes, and to enable comparison of randomised trials.

Neonatal encephalopathy due to suspected hypoxic ischemic encephalopathy: pathophysiology, current, and emerging treatments

BACKGROUND

Neonatal encephalopathy (NE) due to suspected hypoxic-ischemic encephalopathy (HIE), referred to as NESHIE, is a clinical diagnosis in late preterm and term newborns. It occurs as a result of impaired cerebral blood flow and oxygen delivery during the peripartum period and is used until other causes of NE have been discounted and HIE is confirmed. Therapeutic hypothermia (TH) is the only evidence-based and clinically approved treatment modality for HIE. However, the limited efficacy and uncertain benefits of TH in some low- to middle-income countries (LMICs) and the associated need for intensive monitoring have prompted investigations into more accessible and effective stand-alone or additive treatment options.

DATA SOURCES

This review describes the rationale and current evidence for alternative treatments in the context of the pathophysiology of HIE based on literatures from Pubmed and other online sources of published data.

RESULTS

The underlining mechanisms of neurotoxic effect, current clinically approved treatment, various categories of emerging treatments and clinical trials for NE are summarized in this review. Melatonin, caffeine citrate, autologous cord blood stem cells, Epoetin alfa and Allopurinal are being tested as potential neuroprotective agents currently.

CONCLUSION

This review describes the rationale and current evidence for alternative treatments in the context of the pathophysiology of HIE. Neuroprotective agents are currently only being investigated in high- and middle-income settings. Results from these trials will need to be interpreted and validated in LMIC settings. The focus of future research should therefore be on the development of inexpensive, accessible monotherapies and should include LMICs, where the highest burden of NESHIE exists.

Long-Term Outcomes Following Hypoxic Ischemic Encephalopathy

Hypoxic ischemic encephalopathy (HIE) is the most common cause of neonatal encephalopathy and results in significant morbidity and mortality. Long-term outcomes of the condition encompass impairments across all developmental domains. While therapeutic hypothermia (TH) has improved outcomes for term and late preterm infants with moderate to severe HIE, trials are ongoing to investigate the use of TH for infants with mild or preterm HIE. There is no evidence that adjuvant therapies in combination with TH improve long-term outcomes. Numerous trials of various adjuvant therapies are underway in the quest to further improve outcomes for infants with HIE.

Lower plasma melatonin levels in non-hypoxic premature newborns associated with neonatal pain

We analyzed plasma melatonin levels in different groups of preterm newborns without hypoxia and their relationship with several perinatal variables like gestational age or neonatal pain. Prospective cohort study of preterm newborns (PTNB) without perinatal hypoxia, Apgar > 6 at 5 min, and oxygen needs on the third day of life. We compared melatonin levels at day 3 of life in different groups of non-hypoxic preterm infants (Student's t-tests, Mann-Whitney U, and chi2) and analyzed the relationship of melatonin with GA, birth weight, neonatal pain (Premature Infant Pain Profile (PIPP) scale), caffeine treatment, parenteral nutrition, or the development of free radical diseases (correlation study, linear regression) and factors associated with moderate/intense pain and free radical diseases (logistic regression analysis). Sixty-one preterm infants with gestational age (GA) of 30.7 ± 2.0 weeks with no oxygen requirements at day 3 of life were studied with plasma melatonin levels of 33.8 ± 12.01 pg/ml. Preterm infants weighing < 1250 g at birth had lower plasma melatonin levels (p = 0.05). Preterm infants with moderate or severe pain (PPIPP > 5) have lower melatonin levels (p = 0.01), and being preterm with PIPP > 5 is associated with lower plasma melatonin levels (p = 0.03). Being very preterm (GA < 32 GS), having low weight for gestational age (LWGA), receiving caffeine treatment, or requiring parenteral nutrition did not modify melatonin levels in non-hypoxic preterm infants (p = NS). Melatonin on day 3 of life in non-hypoxic preterm infants is not associated with later development of free radical diseases (BPD, sepsis, ROP, HIV, NEC).

CONCLUSION

We observed that preterm infants with moderate to severe pain have lower melatonin levels. These findings are relevant because they reinforce the findings of other authors that melatonin supplementation decreases pain and oxidative stress in painful procedures in premature infants. Further studies are needed to evaluate whether melatonin could be used as an analgesic in painful procedures in preterm infants.

TRIAL REGISTRATION

Trial registration was not required since this was an observational study.

WHAT IS KNOWN

• Melatonin is a potent antioxidant and free radical scavenger in newborns under stress conditions: hypoxia, acidosis, hypotension, painful procedures, or parenteral nutrition. • Pain stimulates the production of melatonin. • Various studies conclude that melatonin administration decreases pain during the neonatal period.

WHAT IS NEW

• Non-hypoxic preterm infants with moderate to severe pain (PIPP>5) have lower levels of melatonin. • Administration of caffeine and treatment with parenteral nutrition do not modify melatonin levels in non-hypoxic preterm infants.

Significance of Melatonin in the Regulation of Circadian Rhythms and Disease Management

Melatonin, the 'hormone of darkness' is a neuronal hormone secreted by the pineal gland and other extra pineal sites. Responsible for the circadian rhythm and seasonal behaviour of vertebrates and mammals, melatonin is responsible for regulating various physiological conditions and the maintenance of sleep, body weight and the neuronal activities of the ocular sites. With its unique amphiphilic structure, melatonin can cross the cellular barriers and elucidate its activities in the subcellular components, including mitochondria. Melatonin is a potential scavenger of oxygen and nitrogen-reactive species and can directly obliterate the ROS and RNS by a receptor-independent mechanism. It can also regulate the pro- and anti-inflammatory cytokines in various pathological conditions and exhibit therapeutic activities against neurodegenerative, psychiatric disorders and cancer. Melatonin is also found to show its effects on major organs, particularly the brain, liver and heart, and also imparts a role in the modulation of the immune system. Thus, melatonin is a multifaceted candidate with immense therapeutic potential and is still considered an effective supplement on various therapies. This is primarily due to rectification of aberrant circadian rhythm by improvement of sleep quality associated with risk development of neurodegenerative, cognitive, cardiovascular and other metabolic disorders, thereby enhancing the quality of life.

The predictive value of MRI scores for neurodevelopmental outcome in infants with neonatal encephalopathy

BACKGROUND

MRI scoring systems are utilized to quantify brain injury and predict outcome in infants with neonatal encephalopathy (NE). Our aim was to evaluate the predictive accuracy of total scores, white matter (WM) and grey matter (GM) subscores of Barkovich and Weeke scoring systems for neurodevelopmental outcome at 2 years of age in infants receiving therapeutic hypothermia for NE.

METHODS

Data of 162 infants were analyzed in this retrospective cohort study. DeLong tests were used to compare areas under the curve of corresponding items of the two scoring systems. LASSO logistic regression was carried out to evaluate the association between MRI scores and adverse composite (death or severe disabilities), motor and cognitive outcomes (Bayley developmental index <70).

RESULTS

Weeke scores predicted each outcome measure with greater accuracy than the corresponding items of Barkovich system (DeLong tests p < 0.03). Total scores, GM and cerebellum involvement were associated with increased odds for adverse outcomes, in contrast to WM injury, after adjustment to 5' Apgar score, first postnatal lactate and aEEG normalization within 48 h.

CONCLUSION

A more detailed scoring system had better predictive value for adverse outcome. GM injury graded on both scoring systems was an independent predictor of each outcome measure.

IMPACT STATEMENTS

A more detailed MRI scoring system had a better predictive value for motor, cognitive and composite outcomes. While hypoxic-ischemic brain injuries in the deep grey matter and cerebellum were predictive of adverse outcome, white matter injury including cortical involvement was not associated with any of the outcome measures at 2 years of age. Structured MRI evaluation based on validated scores may aid future clinical research, as well as inform parents and caregivers to optimize care beyond the neonatal period.

Peculiarities of melatonin levels in preterm infants

BACKGROUND

Melatonin plays an important role in organism functioning, child growth, and development. Of particular importance is melatonin for preterm infants. The aim of our research was to study the peculiarities of melatonin levels depending on various factors in preterm infants with gestational age (GA) of less than 34 weeks.

METHODS

The study involved 104 preterm infants with GA less than 34 weeks who were treated in the neonatal intensive care unit (NICU). The level of melatonin in urine samples was determined by an enzyme-linked immunosorbent assay.

RESULTS

Melatonin concentration was significantly lower in extremely and very preterm infants compared to moderate preterm (3.57 [2.10; 5.06] ng/ml vs. 4.96 [3.20; 8.42] ng/ml, p = 0.007) and was positively correlated with GA (Spearman r = 0.32; p < 0.001). Positive correlations were revealed between melatonin levels and Apgar scores at the 1st (Spearman r = 0.31; p = 0.001) and 5th minutes after birth (Spearman r = 0.35; p < 0.001). Melatonin levels were lower in newborns with respiratory distress syndrome (p = 0.011). No significant correlations were found between melatonin concentration and birth weight (Spearman r = 0.15; p = 0.130). There were no associations of melatonin concentrations and mode of delivery (p = 0.914), the incidence of early-onset sepsis (p = 0.370) and intraventricular hemorrhages (p = 0.501), and mechanical ventilation (p = 0.090). The results of multiple regression showed that gestational age at birth was the most significant predictor of melatonin level in preterm infants (B = 0.507; p = 0.001).

CONCLUSION

Gestational age and the Apgar score were associated with decreased melatonin levels in preterm infants. The level of melatonin in extremely and very preterm infants was lower compared to moderate preterm infants.

Comparison of Different Adjuvant Therapies for Hypothermia in Neonates with Hypoxic-Ischemic Encephalopathy: A Systematic Review and Network Meta-Analysis

OBJECTIVES

Neonatal hypoxic-ischemic encephalopathy is a major cause of perinatal death and neurodevelopmental impairment (NDI). Hypothermia (HT) is the standard of care; however, additional neuroprotective agents are required to improve prognosis. The authors searched for all drugs in combination with HT and compared their effects using a network meta-analysis.

METHODS

The authors searched PubMed, Embase, and Cochrane Library until September 24, 2022 for articles assessing mortality, NDI, seizures, and abnormal brain imaging findings in neonates with hypoxic-ischemic encephalopathy. Direct pairwise comparisons and a network meta-analysis was performed under random effects.

RESULTS

Thirteen randomized clinical trials enroled 902 newborns treated with six combination therapies: erythropoietin magnesium sulfate, melatonin (MT), topiramate, xenon, and darbepoetin alfa. The results of all comparisons were not statistically significant, except for NDI, HT vs. MT+HT: odds ratio = 6.67, 95% confidence interval = 1.14-38.83; however, the overall evidence quality was low for the small sample size.

CONCLUSIONS

Currently, no combination therapy can reduce mortality, seizures, or abnormal brain imaging findings in neonatal hypoxic-ischemic encephalopathy. According to low quality evidence, HT combined with MT may reduce NDI.

Emerging therapeutic strategies in hypoxic-ischemic encephalopathy: a focus on cognitive outcomes

Perinatal hypoxia-ischemia represents a significant risk to CNS development, leading to high mortality rates, diverse damages, and persistent neurological deficits. Despite advances in neonatal medicine in recent decades, the incidence of HIE remains substantial. Motor deficits can manifest early, while cognitive impairments may be diagnosed later, emphasizing the need for extended follow-up. This review aims to explore potential candidates for therapeutic interventions for hypoxic-ischemic encephalopathy (HIE), with a focus on cognitive deficits. We searched randomized clinical trials (RCT) that tested drug treatments for HIE and evaluated cognitive outcomes. The results included studies on erythropoietin, melatonin, magnesium sulfate, topiramate, and a combination of vitamin C and ibuprofen. Although there are several indications of the efficacy of these drugs among animal models, considering neuroprotective properties, the RCTs failed to provide complete effectiveness in the context of cognitive impairments derived from HIE. More robust RCTs are still needed to advance our knowledge and to establish standardized treatments for HIE.

Melatonin Use during Pregnancy and Lactation Complicated by Oxidative Stress: Focus on Offspring's Cardiovascular-Kidney-Metabolic Health in Animal Models

Cardiovascular-kidney-metabolic (CKM) syndrome has emerged as a major global public health concern, posing a substantial threat to human health. Early-life exposure to oxidative stress may heighten vulnerability to the developmental programming of adult diseases, encompassing various aspects of CKM syndrome. Conversely, the initiation of adverse programming processes can potentially be thwarted through early-life antioxidant interventions. Melatonin, originally recognized for its antioxidant properties, is an endogenous hormone with diverse biological functions. While melatonin has demonstrated benefits in addressing disorders linked to oxidative stress, there has been comparatively less focus on investigating its reprogramming effects on CKM syndrome. This review consolidates the current knowledge on the role of oxidative stress during pregnancy and lactation in inducing CKM traits in offspring, emphasizing the underlying mechanisms. The multifaceted role of melatonin in regulating oxidative stress, mediating fetal programming, and preventing adverse outcomes in offspring positions it as a promising reprogramming strategy. Currently, there is a lack of sufficient information in humans, and the available evidence primarily originates from animal studies. This opens up new avenues for novel preventive intervention in CKM syndrome.

Systematic review of melatonin in cerebral ischemia-reperfusion injury: critical role and therapeutic opportunities

Cerebral ischemia-reperfusion (I/R) injury is the predominant causes for the poor prognosis of ischemic stroke patients after reperfusion therapy. Currently, potent therapeutic interventions for cerebral I/R injury are still very limited. Melatonin, an endogenous hormone, was found to be valid in preventing I/R injury in a variety of organs. However, a systematic review covering all neuroprotective effects of melatonin in cerebral I/R injury has not been reported yet. Thus, we perform a comprehensive overview of the influence of melatonin on cerebral I/R injury by collecting all available literature exploring the latent effect of melatonin on cerebral I/R injury as well as ischemic stroke. In this systematic review, we outline the extensive scientific studies and summarize the beneficial functions of melatonin, including reducing infarct volume, decreasing brain edema, improving neurological functions and attenuating blood-brain barrier breakdown, as well as its key protective mechanisms on almost every aspect of cerebral I/R injury, including inhibiting oxidative stress, neuroinflammation, apoptosis, excessive autophagy, glutamate excitotoxicity and mitochondrial dysfunction. Subsequently, we also review the predictive and therapeutic implications of melatonin on ischemic stroke reported in clinical studies. We hope that our systematic review can provide the most comprehensive introduction of current advancements on melatonin in cerebral I/R injury and new insights into personalized diagnosis and treatment of ischemic stroke.

Mitochondria-targeted cerium vanadate nanozyme suppressed hypoxia-ischemia injury in neonatal mice via intranasal administration

Oxidative stress is a major obstacle for neurological functional recovery after hypoxia-ischemia (HI) brain damage. Nanozymes with robust anti-oxidative stress properties offer a therapeutic option for HI injury. However, insufficiency of nanozyme accumulation in the HI brain by noninvasive administration hinders their application. Herein, we reported a cerium vanadate (CeVO4) nanozyme to realize a noninvasive therapy for HI brain in neonatal mice by targeting brain neuron mitochondria. CeVO4 nanozyme with superoxide dismutase activity mainly co-located with neuronal mitochondria 1 h after administration. Pre- and post-HI administrations of CeVO4 nanozyme were able to attenuate acute brain injury, by inhibiting caspase-3 activation, microglia activation, and proinflammation cytokine production in the lesioned cortex 2 d after HI injury. Moreover, CeVO4 nanozyme administration led to short- and long-term functional recovery following HI insult without any potential toxicities in peripheral organs of mice even after prolonged delivery for 4 weeks. These beneficial effects of CeVO4 nanozyme were associated with suppressed oxidative stress and up-regulated nuclear factor erythroid-2-related factor 2 (Nrf2) expression. Finally, we found that Nrf2 inhibition with ML385 abolished the protective effects of CeVO4 nanozyme on HI injury. Collectively, this strategy may provide an applicative perspective for CeVO4 nanozyme therapy in HI brain damage via noninvasive delivery.

Potential Adjuncts to Therapeutic Hypothermia to Mitigate Multiorgan Injury in Perinatal Hypoxia-Ischemia

Over the last 2 decades, therapeutic hypothermia has become the standard of care to reduce morbidity and mortality in neonates affected by moderate-to-severe hypoxic-ischemic encephalopathy (HIE). There is a significant interest in improving the neurologic outcomes of neonatal HIE, ranging from adjunctive therapy to therapeutic hypothermia. Importantly, the pathophysiologic mechanisms underlying HIE also affect multiple other organs, contributing to high morbidity and mortality in this patient population. This review focuses on the adjunct therapies currently under investigation to mitigate the impact of hypoxic-ischemic injury on the brain, kidneys, liver, heart, and gastrointestinal system.

Melatonin or its analogs as premedication to prevent emergence agitation in children: a systematic review and meta-analysis

BACKGROUND

Emergence agitation (EA) is a prevalent complication in children following general anesthesia. Several studies have assessed the relationship between melatonin or its analogs and the incidence of pediatric EA, yielding conflicting results. This meta-analysis aims to assess the effects of premedication with melatonin or its analogs on preventing EA in children after general anesthesia.

METHODS

PubMed, EMBASE, the Cochrane Library, ProQuest Dissertations & Theses Global, Web of Science, CNKI, Wanfang Data, clinicaltrials.gov, and WHO International Clinical Trials Registry Platform were searched until 25 November 2022. We included randomized controlled trials that assessed EA in patients less than 18 years old who underwent general anesthesia. We excluded studies that did not use a specific evaluation to assess EA.

RESULTS

Nine studies (951 participants) were included in this systematic review. Melatonin significantly reduced the incidence of EA compared with placebos (risk ratio 0.40, 95% CI 0.26 to 0.61, P < 0.01) and midazolam (risk ratio 0.48, 95% CI 0.32 to 0.73, P < 0.01). Dexmedetomidine remarkably decreased the incidence of EA compared with melatonin (risk ratio 2.04, 95% CI 1.11 to 3.73, P = 0.02).

CONCLUSIONS

Melatonin premedication significantly decreases the incidence of EA compared with placebos and midazolam. Dexmedetomidine premedication has a stronger effect than melatonin in preventing EA. Nevertheless, further studies are warranted to reinforce and validate the conclusion on the efficacy of melatonin premedication in mitigating EA in pediatric patients.

Acquired Brain Injuries Across the Perinatal Spectrum: Pathophysiology and Emerging Therapies

The development of the central nervous system can be directly disrupted by a variety of acquired factors, including infectious, inflammatory, hypoxic-ischemic, and toxic insults. Influences external to the fetus also impact neurodevelopment, including placental health, maternal comorbidities, adverse experiences, environmental exposures, and social determinants of health. Acquired perinatal brain insults tend to affect the developing brain in a stage-specific manner that reflects the susceptible cell types, developmental processes, and risk factors present at the time of the insult. In this review, we discuss the pathophysiology, neurodevelopmental outcomes, and management of common acquired perinatal brain conditions. In the fetal brain, we divide insults based on trimester, and in the postnatal brain, we focus on common pathologies that have a presentation dependent on gestational age at birth: white matter injury and germinal matrix hemorrhage/intraventricular hemorrhage in preterm infants and hypoxic-ischemic encephalopathy in term infants. Although specific treatments for fetal and newborn brain disorders are currently limited, we emphasize therapies in preclinical or early clinical phases of the development pipeline. The growing number of novel cell type- and stage-specific emerging therapies suggests that in the near future we may have a dramatically improved ability to treat acquired perinatal brain disorders and to mitigate the associated neurodevelopmental consequences.

Common sleep disorders in pregnancy: a review

In this review, we provide a comprehensive overview of common sleep disorders during pregnancy, including their characterization, prevalence, risk factors, and possible contribution to maternal and fetal outcomes. We conducted a quasi-systematic literature search of the MEDLINE database and identified 744 studies from 1991 through 2021, inclusive, that met our inclusion criteria. We synthesized the existing literature on sleep disorders during pregnancy and highlighted controversies, research gaps, and needed clinical developments. Our review covers a range of sleep disorders, including insomnia, obstructive sleep apnea, restless legs syndrome, and circadian rhythm disorders. We discuss the prevalence of these disorders in pregnancy and their potential impact on maternal and fetal health outcomes. We also explore the relationship between sleep disorders, pre-pregnancy comorbidities such as obesity, and pregnancy-related conditions such as gestational diabetes mellitus and preeclampsia. In addition to summarizing the existing literature on sleep disorders during pregnancy, we also highlight opportunities for further research in this area. We suggest that future studies should strive to employ validated and objective measurement tools for sleep disorders and prioritize utilization of longitudinal methods with participant follow-up through postpartum, mid-life, menopause, and beyond. We also put forward investigation into the impact of circadian rhythm disruption on reproductive physiology and early pregnancy outcomes as an area of important work. Overall, our review provides valuable insights on sleep and reproduction and into common sleep disorders during pregnancy and their potential impact on maternal and fetal health outcomes.

[Research research on the use of melatonin in combination with therapeutic hypothermia for the treatment of neonatal hypoxic-ischemic encephalopathy]

Neonatal hypoxic-ischemic encephalopathy (HIE) remains one of the leading causes of death and long-term neurodevelopmental disorders in full-term neonates, and there is currently no curative treatment. Therapeutic hypothermia is now a standard therapy for HIE in the neonatal intensive care unit, but its safety and efficacy in remote areas remains unclear. Melatonin is an indole endocrine hormone mainly produced by the pineal gland and it has the ability to easily penetrate the blood-brain barrier. Through receptor and non-receptor mechanisms, melatonin exerts anti-oxidative and anti-inflammatory effects and participates in the regulation of organelle function and the inhibition of cell death. Melatonin is considered one of the most promising drugs for the treatment of HIE based on its reliable safety profile and clinical/preclinical results. This article reviews the recent research on the use of melatonin in combination with therapeutic hypothermia for the treatment of neonatal HIE.

Neuroprotective Effects of Delayed TGF-β1 Receptor Antagonist Administration on Perinatal Hypoxic-Ischemic Brain Injury

Hypoxic-ischemic (HI) brain injury in neonatal encephalopathy triggers a wave of neuroinflammatory events attributed to causing the progressive degeneration and functional deficits seen weeks after the primary damage. The cellular processes mediating this prolonged neurodegeneration in HI injury are not sufficiently understood. Consequently, current therapies are not fully protective. In a recent study, we found significant improvements in neurologic outcomes when a small molecule antagonist for activin-like kinase 5 (ALK5), a transforming growth factor beta (TGF-β) receptor was used as a therapeutic in a rat model of moderate term HI. Here, we have extended those studies to a mouse preterm pup model of HI. For these studies, postnatal day 7 CD1 mice of both sexes were exposed to 35-40 min of HI. Beginning 3 days later, SB505124, the ALK5 receptor antagonist, was administered systemically through intraperitoneal injections performed every 12 h for 5 days. When evaluated 23 days later, SB505124-treated mice had ∼2.5-fold more hippocampal area and ∼2-fold more thalamic tissue. Approximately 90% of the ipsilateral hemisphere (ILH) was preserved in the SB505124-treated HI mice compared to the vehicle-treated HI mice, where the ILH was ∼60% of its normal size. SB505124 also preserved the subcortical white matter. SB505124 treatment preserved levels of aquaporin-4 and n-cadherin, key proteins associated with blood-brain barrier function. Importantly, SB505124 administration improved sensorimotor function as assessed by a battery of behavioral tests. Altogether, these data lend additional support to the conclusion that SB505124 is a candidate neuroprotective molecule that could be an effective treatment for HI-related encephalopathy in moderately injured preterm infants.

Traumatic Brain Injury, Sleep, and Melatonin-Intrinsic Changes with Therapeutic Potential

Traumatic brain injury (TBI) is one of the most prevalent causes of morbidity in the United States and is associated with numerous chronic sequelae long after the point of injury. One of the most common long-term complaints in patients with TBI is sleep dysfunction. It is reported that alterations in melatonin follow TBI and may be linked with various sleep and circadian disorders directly (via cellular signaling) or indirectly (via free radicals and inflammatory signaling). Work over the past two decades has contributed to our understanding of the role of melatonin as a sleep regulator and neuroprotective anti-inflammatory agent. Although there is increasing interest in the treatment of insomnia following TBI, a lack of standardization and rigor in melatonin research has left behind a trail of non-generalizable data and ambiguous treatment recommendations. This narrative review describes the underlying biochemical properties of melatonin as they are relevant to TBI. We also discuss potential benefits and a path forward regarding the therapeutic management of TBI with melatonin treatment, including its role as a neuroprotectant, a somnogen, and a modulator of the circadian rhythm.

Brain-Oriented Strategies for Neuroprotection of Asphyxiated Newborns in the First Hours of Life

Perinatal asphyxia represents the first cause of severe neurological disabilities and the second cause of neonatal death in term-born babies. Currently, no treatment can prevent immediate cell death from necrosis, but some therapeutic interventions, such as therapeutic hypothermia (TH), can reduce delayed cell death from apoptosis. TH significantly improves the combined outcome of mortality or major neurodevelopmental disability, but the number of patients to be treated is 7 to get 1 child with no adverse neurological outcome. The aim of this educational review is to analyze the other care strategies to be implemented to improve the neurological outcome of children with hypoxic ischemic encephalopathy (HIE). Hypocapnia, hypoglycemia, pain control, and functional brain monitoring are recognized as appropriate approaches to improve outcome in critically ill infants with HIE. Pharmacologic neuroprotective adjuncts are currently under investigation. New drugs such as allopurinol and melatonin seem to provide positive effects although more randomized controlled trials are required to establish the effective therapeutic scheme. In the meantime, sustaining the respiratory, metabolic, and cardiovascular system during TH can be a valuable aid in managing and treating the patient with HIE in an optimal way.

The relationship of melatonin concentration in preterm infants and adverse outcomes in the late neonatal period

Introduction

The aim of research was to assess the melatonin concentrations in the early neonatal period as a predictor of adverse outcomes of late neonatal period in preterm infants and to estimate its optimal predictive cut-off values.

Materials and methods

A total of 115 preterm infants admitted to the neonatal intensive care unit were screened for eligibility, five did not meet the criteria, six parents declined the participation. So, a total of 104 preterm infants with gestational age 25-34 weeks were included in research. The concentration of melatonin in urine was determined by the Enzyme Immunoassay method (Human Melatonin Sulfate ELISA kit, Elabscience, China). The Mann-Whitney U-test and analysis of the receiver operating characteristic (ROC) curve were used in statistical analysis.

Results

Analysis of the ROC curves has revealed optimal cut-off values for urinary melatonin concentration to predict late outcomes. Melatonin concentration below 3.58 ng/ml with sensitivity of 72% can predict development of retinopathy of prematurity (ROP) (AUC = 0.73; 95% confidence intervals (CI) 0.61-0.86). Good diagnostic accuracy (AUC = 0.80; 95% CI 0.67-0.93) has been shown for bronchopulmonary dysplasia (BPD). The optimal cut-off value for melatonin concentration in BPD prediction is 3.71 ng/ml (sensitivity 80%, specificity 64%). Urinary melatonin concentration below 3.79 ng/ml can be associated with late-onset sepsis (AUC = 0.76; 95% CI 0.64-0.87; sensitivity 72%; specificity 62%). There were no significant associations between melatonin concentration and necrotizing enterocolitis (P = 0.912).

Conclusion

Urinary melatonin concentration below the certain cut-off values in the early neonatal period may serve as one of the predictors of adverse outcomes such as BPD, ROP, and late-onset sepsis in the late neonatal period in preterm infants.

Neonatal asphyxia as an inflammatory disease: Reactive oxygen species and cytokines

Neonatologists resuscitate asphyxiated neonates by every available means, including positive ventilation, oxygen therapy, and drugs. Asphyxiated neonates sometimes present symptoms that mimic those of inflammation, such as fever and edema. The main pathophysiology of the asphyxia is inflammation caused by hypoxic-ischemic reperfusion. At birth or in the perinatal period, neonates may suffer several, hypoxic insults, which can activate inflammatory cells and inflammatory mediator production leading to the release of larger quantities of reactive oxygen species (ROS). This in turn triggers the production of oxygen stress-induced high mobility group box-1 (HMGB-1), an endogenous damage-associated molecular patterns (DAMPs) protein bound to toll-like receptor (TLR) -4, which activates nuclear factor-kappa B (NF-κB), resulting in the production of excess inflammatory mediators. ROS and inflammatory mediators are produced not only in activated inflammatory cells but also in non-immune cells, such as endothelial cells. Hypothermia inhibits pro-inflammatory mediators. A combination therapy of hypothermia and medications, such as erythropoietin and melatonin, is attracting attention now. These medications have both anti-oxidant and anti-inflammatory effects. As the inflammatory response and oxidative stress play a critical role in the pathophysiology of neonatal asphyxia, these drugs may contribute to improving patient outcomes.

Melatonin: A Potential Candidate for the Treatment of Experimental and Clinical Perinatal Asphyxia

Perinatal asphyxia is considered to be one of the major causes of brain neurodegeneration in full-term newborns. The worst consequence of perinatal asphyxia is neurodegenerative brain damage, also known as hypoxic-ischemic encephalopathy. Hypoxic-ischemic encephalopathy is the leading cause of mortality in term newborns. To date, due to the complex mechanisms of brain damage, no effective or causal treatment has been developed that would ensure complete neuroprotection. Although hypothermia is the standard of care for hypoxic-ischemic encephalopathy, it does not affect all changes associated with encephalopathy. Therefore, there is a need to develop effective treatment strategies, namely research into new agents and therapies. In recent years, it has been pointed out that natural compounds with neuroprotective properties, such as melatonin, can be used in the treatment of hypoxic-ischemic encephalopathy. This natural substance with anti-inflammatory, antioxidant, anti-apoptotic and neurofunctional properties has been shown to have pleiotropic prophylactic or therapeutic effects, mainly against experimental brain neurodegeneration in hypoxic-ischemic neonates. Melatonin is a natural neuroprotective hormone, which makes it promising for the treatment of neurodegeneration after asphyxia. It is supposed that melatonin alone or in combination with hypothermia may improve neurological outcomes in infants with hypoxic-ischemic encephalopathy. Melatonin has been shown to be effective in the last 20 years of research, mainly in animals with perinatal asphyxia but, so far, no clinical trials have been performed on a sufficient number of newborns. In this review, we summarize the advantages and limitations of melatonin research in the treatment of experimental and clinical perinatal asphyxia.

Human wharton-jelly mesenchymal stromal cells reversed apoptosis and prevented multi-organ damage in a newborn model of experimental asphyxia

In this study, the effect of applying wharton jelly mesenchymal stromal cells (WJ-MSC) isolated from the human umbilical cord tissue on the neonatal mouse model caused experimental asphyxia in mice was investigated. WJ-MSC surface markers (CD44, CD90, CD105) were characterised by immunofluorescence staining, and pluripotency genes (Nanog, Oct-4, Sox-2) were characterised by qPCR. Blood, prefrontal cortex, cerebellum, hippocampus, lung, heart, kidney, and liver tissues were analysed twenty days after subcutaneously administered WJ-MSC. WJ-MSC administration significantly decreased serum TNF-α, NSE, GFAP, and IL-6 levels in the asphyxia mice. It was determined that WJ-MSC application in tissues accelerated cell regeneration and decreased oxidative stress. In conclusion, this study showed that multiorgan damage in asphyxia could be prevented by applying WJ-MSC at an early stage. Therefore, WJ-MSC application in infants with neonatal asphyxia in the clinic may be an innovative method in the future.

Hypothermia combined with neuroprotective adjuvants shortens the duration of hospitalization in infants with hypoxic ischemic encephalopathy: Meta-analysis

Objective: Therapeutic hypothermia (TH) is the current standard of care for neonatal hypoxic-ischemic encephalopathy (HIE), yet morbidity and mortality remain significant. Adjuvant neuroprotective agents have been suggested to augment hypothermic-mediated neuroprotection. This analysis aims to identify the classes of drugs that have been used in combination with hypothermia in the treatment of neonatal HIE and determine whether combination therapy is more efficacious than TH alone. Methods: A systematic search of PubMed, Embase and Medline from conception through December 2022 was conducted. Randomized- and quasi-randomized controlled trials, observational studies and retrospective studies evaluating HIE infants treated with combination therapy versus TH alone were selected. Primary reviewers extracted information on mortality, neurodevelopmental impairment and length of hospitalization for meta-analyses. Effect sizes were pooled using a random-effects model and measured as odds ratio (OR) or mean difference (MD) where applicable, and 95% confidence intervals (CI) were calculated. Risk of bias was assessed using the tool from the Cochrane Handbook for Systematic Reviews of Interventions. Results: The search strategy collected 519 studies, 16 of which met analysis inclusion criteria. HIE infants totaled 1,288 infants from included studies, 646 infants received some form of combination therapy, while 642 received TH alone. GABA receptor agonists, NMDA receptor antagonists, neurogenic and angiogenic agents, stem cells, glucocorticoids and antioxidants were identified as candidate adjuvants to TH that have been evaluated in clinical settings compared to TH alone. Length of hospitalization was significantly reduced in infants treated with combination therapy (MD -4.81, 95% CI [-8.42. to -1.19], p = .009) compared to those treated with TH alone. Risk of mortality and neurodevelopmental impairment did not differ between combination therapy and TH alone groups. Conclusion: Compared to the current standard of care, administration of neuroprotective adjuvants with TH reduced the duration of hospitalization but did not impact the risk of mortality or neurodevelopmental impairment in HIE infants. Meta-analysis was limited by a moderate risk of bias among included studies and small sample sizes. This analysis highlights the need for preclinical trials to conduct drug development studies in hypothermic settings to identify relevant molecular targets that may offer additive or synergistic neuroprotection to TH, and the need for larger powered clinical trials to determine the dose and timing of administration at which maximal clinical benefits are observed for adjuvant neuroprotectants.

Incidence and outcomes of intrapartum-related neonatal encephalopathy in low-income and middle-income countries: a systematic review and meta-analysis

AIM

To examine the incidence of intrapartum-related neonatal encephalopathy, and neonatal mortality and neurodevelopmental outcomes associated with it in low-income and middle-income countries.

METHODS

Reports were included when neonatal encephalopathy diagnosed clinically within 24 hours of birth in term or near-term infants born after intrapartum hypoxia-ischaemia defined as any of the following: (1) pH≤7.1 or base excess ≤-12 or lactate ≥6, (2) Apgar score ≤5 at 5 or 10 min, (3) continuing resuscitation at 5 or 10 min or (4) no cry from baby at 5 or 10 min. Peer-reviewed articles were searched from Ovid MEDLINE, Cochrane, Web of Science and WHO Global Index Medicus with date limits 1 November 2009 to 17 November 2021. Risk of bias was assessed using modified Newcastle Ottawa Scale. Inverse variance of heterogenicity was used for meta-analyses.

RESULTS

There were 53 reports from 51 studies presenting data on 4181 children with intrapartum-related neonatal encephalopathy included in the review. Only five studies had data on incidence, which ranged from 1.5 to 20.3 per 1000 live births. Neonatal mortality was examined in 45 studies and in total 636 of the 3307 (19.2%) infants died. Combined outcome of death or moderate to severe neurodevelopmental disability was reported in 19 studies and occurred in 712 out of 1595 children (44.6%) with follow-up 1 to 3.5 years.

CONCLUSION

Though there has been progress in some regions, incidence, case mortality and morbidity in intrapartum-related neonatal encephalopathy has been static in the last 10 years.

PROSPERO REGISTRATION NUMBER

CRD42020177928.

Neonatal Hypoxic-Ischemic Encephalopathy: Perspectives of Neuroprotective and Neuroregenerative Treatments

Hypoxic-ischemic encephalopathy (HIE) is a serious condition that could have deleterious neurological outcomes, such as cerebral palsy, neuromotor disability, developmental disability, epilepsy, and sensitive or cognitive problems, and increase the risk of death in severe cases. Once HIE occurs, molecular cascades are triggered favoring the oxidative stress, excitotoxicity, and inflammation damage that promote cell death via apoptosis or necrosis. Currently, the therapeutic hypothermia is the standard of care in HIE; however, it has a small window of action and only can be used in children of more than 36 gestational weeks; for this reason, it is very important to develop new therapies to prevent the progression of the hypoxic-ischemic injury or to develop neuroregenerative therapies in severe HIE cases. The objective of this revision is to describe the emerging treatments for HIE, either preventing cell death for oxidative stress, excitotoxicity, or exacerbated inflammation, as well as describing a new therapeutic approach for neuroregeneration, such as mesenchymal stem cells, brain-derived neurotrophic factor, and gonadotropin realizing hormone agonists.

Neuroprotective therapies in the NICU in term infants: present and future

Outcomes of neonatal encephalopathy (NE) have improved since the widespread implementation of therapeutic hypothermia (TH) in high-resource settings. While TH for NE in term and near-term infants has proven beneficial, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. There is therefore a critical need to find additional pharmacological and non-pharmacological interventions that improve the outcomes for these children. There are many potential candidates; however, it is unclear whether these interventions have additional benefits when used with TH. Although primary and delayed (secondary) brain injury starting in the latent phase after HI are major contributors to neurodisability, the very late evolving effects of tertiary brain injury likely require different interventions targeting neurorestoration. Clinical trials of seizure management and neuroprotection bundles are needed, in addition to current trials combining erythropoietin, stem cells, and melatonin with TH. IMPACT: The widespread use of therapeutic hypothermia (TH) in the treatment of neonatal encephalopathy (NE) has reduced the associated morbidity and mortality. However, 30-50% of infants with moderate-to-severe NE treated with TH still suffer death or significant impairments. This review details the pathophysiology of NE along with the evidence for the use of TH and other beneficial neuroprotective strategies used in term infants. We also discuss treatment strategies undergoing evaluation at present as potential adjuvant treatments to TH in NE.

Human-rat integrated microRNAs profiling identified a new neonatal cerebral hypoxic-ischemic pathway melatonin-sensitive

Neonatal encephalopathy (NE) is a pathological condition affecting long-term neurodevelopmental outcomes. Hypothermia is the only therapeutic option, but does not always improve outcomes; hence, researchers continue to hunt for pharmaceutical compounds. Melatonin treatment has benefitted neonates with hypoxic-ischemic (HI) brain injury. However, unlike animal models that enable the study of the brain and the pathophysiologic cascade, only blood is available from human subjects. Therefore, due to the unavailability of neonatal brain tissue, assumptions about the pathophysiology in pathways and cascades are made in human subjects with NE. We analyzed animal and human specimens to improve our understanding of the pathophysiology in human neonates. A neonate with NE who underwent hypothermia and enrolled in a melatonin pharmacokinetic study was compared to HI rats treated/untreated with melatonin. MicroRNA (miRNA) analyses provided profiles of the neonate's plasma, rat plasma, and rat brain cortexes. We compared these profiles through a bioinformatics tool, identifying Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways common to HI brain injury and melatonin treatment. After evaluating the resulting pathways and the literature, to validate the method, the key proteins expressed in HI brain injury were investigated using cerebral cortexes. The upregulated miRNAs in human neonate and rat plasma helped identify two KEGG pathways, glioma and long-term potentiation, common to HI injury and melatonin treatment. A unified neonatal cerebral melatonin-sensitive HI pathway was designed and validated by assessing the expression of protein kinase Cα (PKCα), phospho (p)-Akt, and p-ERK proteins in rat brain cortexes. PKCα increased in HI-injured rats and further increased with melatonin. p-Akt and p-ERK returned phosphorylated to their basal level with melatonin treatment after HI injury. The bioinformatics analyses validated by key protein expression identified pathways common to HI brain injury and melatonin treatment. This approach helped complete pathways in neonates with NE by integrating information from animal models of HI brain injury.

Melatonin Administration from 2000 to 2020 to Human Newborns with Hypoxic-Ischemic Encephalopathy

Hypoxic-ischemic encephalopathy (HIE) is the main cause of long-term neurodevelopmental morbidity in term born infants worldwide. Melatonin is a hormone with antioxidant and anti-inflammatory effects that make it a promising molecule for the treatment of perinatal asphyxia. Probably, the synergistic use of hypothermia associated with melatonin treatment may improve the neurological outcome in infants with HIE. In the past 20 years, the efficacy of melatonin in reducing oxidative stress has been demonstrated in animals; however, clinical trials with sufficient sample size of newborns are lacking to date. Since in 2000 we were among the first to study the neuroprotective properties of melatonin on infants, in this review, we want to summarize the advantages and limitations of the investigations conducted to date. KEY POINTS: · HIE is the main cause of morbidity in term born infants worldwide.. · Melatonin is a promising molecule for the treatment of perinatal asphyxia.. · This review summarizes advantages and limitations of the investigations conducted on melatonin..

Treatments and therapeutic protocols for the recovery of an asphyxiated new-born: A review of pre-clinical and clinical studies in human neonates and in different animal models

The objective of this review is to ascertain the advantages and disadvantages of several treatments and therapeutic protocols that have been used for the prevention and treatment of perinatal asphyxia in human neonates and in different animal models. Perinatal asphyxia is one of the main causes of mortality worldwide and is an important factor in triggering physio-metabolic disorders that result in serious neurological consequences and learning disorders not only in human foetuses and neonates, but also in animals. In recent years, the search for new pharmacological protocols to prevent and reverse physio-metabolic disorders and brain damage derived from perinatal asphyxia has been and continues to be the subject of intense research. Currently, within these pharmacological protocols, therapeutic strategies have been evaluated that use respiratory and hormonal stimulants, as well as hypothermic therapies in combination with other putative neuroprotective agents. Similarly, energy supplements have been evaluated with the objective of preventing perinatal asphyxia and treating new-borns with this condition, and to decrease the incidence of neonatal and foetal deaths associated with it. However, despite these promising advances, this pathology has persisted, since the administration of these therapies in low doses may not exert a neuroprotective effect or, in high doses, can trigger adverse effects (such as reduced cardiac contractility, reduced cerebral blood flow, poor perfusion, sympathetic and neuroendocrine stimulation, and increased blood viscosity) in human foetuses and neonates as well as in different animal models (rats, piglets, sheep and rabbits). Therefore, it is important to determine the minimum effective dose with which these therapies exert a neuroprotective effect, as well as the mode of administration, the duration of therapy, etc. Therefore, until a powerful strategy is found to improve the consequences of suffocation, this topic will continue to be the subject of intensive research in the future.

Developmental and Early Life Origins of Hypertension: Preventive Aspects of Melatonin

Hypertension represents a major disease burden worldwide. Abundant evidence suggests that hypertension can originate in early life. Adverse programming processes can be prevented by early life intervention-namely, reprogramming-to avoid developing chronic diseases later in life. Melatonin is an endogenously produced hormone with a multifaceted biological function. Although melatonin supplementation has shown benefits for human health, less attention has been paid to exploring its reprogramming effects on the early life origins of hypertension. In this review, first, we discuss the physiological roles of melatonin in pregnancy, fetal development, and the regulation of blood pressure. Then, we summarize the epidemiological and experimental evidence for the early life origins of hypertension. This is followed by a description of the animal models used to examine early melatonin therapy as a reprogramming strategy to protect against the early life origins of hypertension. A deeper understanding of the developmental programming of hypertension and recent advances in early melatonin intervention might provide a path forward in reducing the global burden of hypertension.

Hypoxic Ischemic Encephalopathy (HIE) in Term and Preterm Infants

Hypoxic-ischemic syndrome (HIS) and Hypoxic-ischemic encephalopathy (HIE) are conditions that affect term and premature babies, with different pathophysiology and different brain disorders. HIE appears in 1-6 / 1000 live births and 26/1000 live births in developing countries. 15-20% die in the early neonatal period, while surviving babies have severe neurological impairment, including cerebral palsy, epilepsy, visual and hearing impairment, cognitive impairment, intellectual, behavioural, and social disorders. The hypoxic-ischemic event occurs before, during or after birth. The reasons may be related to the mother, the way of birth, the placenta, and the newborn. The criteria for diagnosis of HIE include a combination of perinatal factors, the need for resuscitation, standard neurological examinations, neurophysiological monitoring, neuroimaging methods and biochemical markers. The most effective treatment for HIE is hypothermia in combination with pharmacological therapy. HIE and HIS are problem that still persist in developing countries due to inadequate obstetric care, neonatal resuscitation, and hypothermia. Current and emerging research for HIE examines new markers for early recognition, treatment, and appropriate neuroprotection of high-risk term and premature infants.

Pharmacological neuroprotection and clinical trials of novel therapies for neonatal peri-intraventricular hemorrhage: a comprehensive review

Peri-intraventricular hemorrhage (PIVH) is a serious condition for preterm infants, caused by traumatic or spontaneous rupture of the germinal matrix (GM) capillary network in the cerebral ventricles. It is a common source of morbidity and mortality in neonates, and risk correlates with earlier delivery, low birth weight, maternal-fetal infection, and vital sign derangements, among others. PIVH typically occurs in the first 72 h of life, and symptoms, when present, manifest most commonly within the first week of life. Prevention remains the primary goal in management, predominantly via prolonging of gestation. Current therapy protocols are center-dependent without consistent consensus guidelines, but infant positioning, homeostatic stabilization, and neuroprotection offer potential options. In this update of pharmacologic neuroprotective therapies for PIVH, we highlight commonly utilized therapies and review the investigative literature. Further multi-institutional clinical trials and basic research studies are required.

New possibilities for neuroprotection in neonatal hypoxic-ischemic encephalopathy

Around 0.75 million babies worldwide suffer from moderate or severe hypoxic-ischemic encephalopathy (HIE) each year resulting in around 400,000 babies with neurodevelopmental impairment. In 2010, neonatal HIE was associated with 2.4% of the total Global Burden of Disease. Therapeutic hypothermia (TH), a treatment that is now standard of care in high-income countries, provides proof of concept that strategies that aim to improve neurodevelopment are not only possible but can also be implemented to clinical practice. While TH is beneficial, neonates with moderate or severe HIE treated with TH still experience devastating complications: 48% (range: 44-53) combined death or moderate/severe disability. There is a concern that TH may not be effective in low- and middle-income countries. Therapies that further improve outcomes are desperately needed, and in high-income countries, they must be tested in conjunction with TH. We have in this review focussed on pharmacological treatment options (e.g. erythropoietin, allopurinol, melatonin, cannabidiol, exendin-4/exenatide). Erythropoietin and allopurinol show promise and are progressing towards the clinic with ongoing definitive phase 3 randomised placebo-controlled trials. However, there remain global challenges for the next decade. Conclusion: There is a need for more optimal animal models, greater industry support/sponsorship, increased use of juvenile toxicology, dose-ranging studies with pharmacokinetic-pharmacodynamic modelling, and well-designed clinical trials to avoid exposure to harmful medications or abandoning putative treatments. What is Known: • Therapeutic hypothermia is beneficial in neonatal hypoxic-ischemic encephalopathy. • Neonates with moderate or severe hypoxic-ischemic encephalopathy treated with therapeutic hypothermia still experience severe sequelae. What is New: • Erythropoietin, allopurinol, melatonin, cannabidiol, and exendin-4/exenatide show promise in conjunction with therapeutic hypothermia. • There is a need for more optimal animal models, greater industry support/sponsorship, increased use of juvenile toxicology, dose-ranging studies with pharmacokinetic-pharmacodynamic modelling, and well-designed clinical trials.

Efficacy of Magnesium Sulfate in Addition to Melatonin Therapy in Neonates With Hypoxic-Ischemic Encephalopathy

Background: One of the most important causes of neonatal deaths in developing nations is birth asphyxia. Though the probability of a complete recovery is very low, hypoxic-ischemic encephalopathy (HIE) associated with asphyxia can be managed with multiple treatment options. The study evaluated the efficacy of the addition of magnesium sulfate (MgSO₄) to melatonin therapy in neonates with HIE.

Methodology: A prospective, observational study was conducted in the department of neonatal intensive care, Pakistan Institute of Medical Sciences Hospital, Islamabad, Pakistan from October 2020 to March 2021. All neonates with an Appearance, Pulse, Grimace, Activity, and Respiration (APGAR) score of less than five at five minutes, umbilical blood pH of less than 7.0, and moderate neonatal encephalopathy as detected on the modified Sarnat score which is a clinical tool used for the assessment of the severity of HIE were included in the study. Neonates with congenital abnormalities, intrauterine growth retardation, neonatal sepsis, and infants born to mothers with diabetes mellitus type 2 were excluded from the study. The infants were randomly assigned to either of the groups, i.e., i) group 1 included neonates who were administered at least three doses of magnesium sulfate (MgSO₄) infusion in addition to melatonin, or ii) group 2 included neonates who were administered melatonin only. Blood samples of all neonates were evaluated and compared between the two groups.

Results: A total of 90 neonates with HIE were included in the study. There was a predominance of female neonates. The mean ages of babies in group 1 and group 2 were 37.2 ± 0.43 and 37.3 ± 0.59 weeks, respectively. The mean weight on the term was 2.88 ± 0.11 and 2.89 ± 0.10, respectively. The Apgar score at 5 mins in group 1 was 1.73 ± 0.81 while in group 2, 1.82 ± 0.94. It was found that there was a more significant improvement in pH after 3 days and after one week of treatment in group 1 as compared to group 2. The mean pH in babies after three days of intervention was 7.23 ± 0.03 in group 1 which was significantly better than group 2 (p<0.0001). After seven days, the mean normalized to 7.39 ± 0.04 in group 1 (p < 0.0001). It was found that in patients in group 1, the mortality was lower than in group 2 (p < 0.0001).

Conclusion: HIE patients who were administered melatonin in combination with magnesium sulfate yielded better patient outcomes. Thus, it was concluded that the use of magnesium sulfate as dual therapy with melatonin improved patient outcomes for HIE. However, it is recommended that similar studies are conducted with a wider range of parameters, such as duration of hospital stay and assessment of the neurological outcomes of the patients.  

Physical Activity vs. Redox Balance in the Brain: Brain Health, Aging and Diseases

It has been proven that physical exercise improves cognitive function and memory, has an analgesic and antidepressant effect, and delays the aging of the brain and the development of diseases, including neurodegenerative disorders. There are even attempts to use physical activity in the treatment of mental diseases. The course of most diseases is strictly associated with oxidative stress, which can be prevented or alleviated with regular exercise. It has been proven that physical exercise helps to maintain the oxidant–antioxidant balance. In this review, we present the current knowledge on redox balance in the organism and the consequences of its disruption, while focusing mainly on the brain. Furthermore, we discuss the impact of physical activity on aging and brain diseases, and present current recommendations and directions for further research in this area.

Resuscitation 2020: Proceedings From the NeoHeart 2020 International Conference

Resuscitation guidelines are developed and revised by medical societies throughout the world. These guidelines are increasingly based on evidence from preclinical and clinical research. The International Liaison Committee on Resuscitation reviews evidence for each resuscitation practice and provides summary consensus statements that inform resuscitation guideline committees. A similar process is used for different populations including neonatal, pediatric, and adult resuscitation. The NeoHeart 2020 Conference brought together experts in resuscitation to discuss recent evidence and guidelines for resuscitation practices. This review summarizes the main focus of discussion from this symposium.

Free Radicals and Neonatal Brain Injury: From Underlying Pathophysiology to Antioxidant Treatment Perspectives

Free radicals play a role of paramount importance in the development of neonatal brain injury. Depending on the pathophysiological mechanisms underlying free radical overproduction and upon specific neonatal characteristics, such as the GA-dependent maturation of antioxidant defenses and of cerebrovascular autoregulation, different profiles of injury have been identified. The growing evidence on the detrimental effects of free radicals on the brain tissue has led to discover not only potential biomarkers for oxidative damage, but also possible neuroprotective therapeutic approaches targeting oxidative stress. While a more extensive validation of free radical biomarkers is required before considering their use in routine neonatal practice, two important treatments endowed with antioxidant properties, such as therapeutic hypothermia and magnesium sulfate, have become part of the standard of care to reduce the risk of neonatal brain injury, and other promising therapeutic strategies are being tested in clinical trials. The implementation of currently available evidence is crucial to optimize neonatal neuroprotection and to develop individualized diagnostic and therapeutic approaches addressing oxidative brain injury, with the final aim of improving the neurological outcome of this population.

Cognitive outcomes in late childhood and adolescence of neonatal hypoxic-ischemic encephalopathy

Hypoxic-ischemic encephalopathy (HIE) is the most common cause of neonatal encephalopathy with a global incidence of approximately 1 to 8 per 1,000 live births. Neonatal encephalopathy can cause neurodevelopmental and cognitive impairments in survivors of hypoxic-ischemic insults with and without functional motor deficits. Normal neurodevelopmental outcomes in early childhood do not preclude cognitive and behavioral difficulties in late childhood and adolescence because cognitive functions are not yet fully developed at this early age. Therapeutic hypothermia has been shown to significantly reduced death and severe disabilities in term newborns with HIE. However, children treated with hypothermia therapy remain at risk for cognitive impairments and follow-up is necessary throughout late childhood and adolescence. Novel adjunctive neuroprotective therapies combined with therapeutic hypothermia may enhance the survival and neurodevelopmental outcomes of infants with HIE. The extent and severity of brain injury on magnetic resonance imaging might predict neurodevelopmental outcomes and lead to targeted interven tions in children with a history of neonatal encephalopathy. We provide a summary of the long-term cognitive outcomes in late childhood and adolescence in children with a history of HIE and the association between pattern of brain injury and neurodevelopmental outcomes.

Oxidative Stress and Respiratory Diseases in Preterm Newborns

Premature infants are exposed to increased generation of reactive oxygen species, and on the other hand, they have a deficient antioxidant defense system. Oxidative insult is a salient part of lung injury that begins as acute inflammatory injury in respiratory distress disease and then evolves into chronic and structural scarring leading to bronchopulmonary dysplasia. Oxidative stress is also involved in the pathogenesis of pulmonary hypertension in newborns through the modulation of the vascular tone and the response to pulmonary vasodilators, with consequent decrease in the density of the pulmonary vessels and thickening of the pulmonary arteriolar walls. Oxidative stress has been recognized as both a trigger and an endpoint for several events, including inflammation, hypoxia, hyperoxia, drugs, transfusions, and mechanical ventilation, with impairment of pulmonary function and prolonged lung damage. Redoxomics is the most fascinating new measure to address lung damage due to oxidative stress. The new challenge is to use omics data to discover a set of biomarkers useful in diagnosis, prognosis, and formulating optimal and individualized neonatal care. The aim of this review was to examine the most recent evidence on the relationship between oxidative stress and lung diseases in preterm newborns. What is currently known regarding oxidative stress-related lung injury pathogenesis and the available preventive and therapeutic strategies are also discussed.

Neuroprotective Agents for Neonates with Hypoxic-Ischemic Encephalopathy

Hypoxic-ischemic encephalopathy (HIE) remains a significant source of long-term neurodevelopmental impairment despite overall improvements in survival without disability in neonates who undergo therapeutic hypothermia. Each phase in the evolution of hypoxic-ischemic injury presents potential pharmacologic targets for neuroprotective agents. Melatonin is a promising emerging therapy for early phases of ischemic injury, but utility is currently limited by the lack of pharmaceutical-grade products. Magnesium has been extensively studied for its neuroprotective effects in the preterm population. Studies in neonates with HIE have produced mixed outcomes. Erythropoietin use in HIE with or without therapeutic hypothermia appears to be safe and may provide additional benefit. Dexmedetomidine, N-acetylcysteine, xenon, and topiramate all have promising animal data, but need additional human trials to elucidate what role they may play in HIE. Frequent review of existing literature is required to ensure provision of evidence-based pharmacologic agents for neuroprotection following HIE.

Therapies for neonatal encephalopathy: Targeting the latent, secondary and tertiary phases of evolving brain injury

In term and near-term neonates with neonatal encephalopathy, therapeutic hypothermia protocols are well established. The current focus is on how to improve outcomes further and the challenge is to find safe and complementary therapies that confer additional protection, regeneration or repair in addition to cooling. Following hypoxia-ischemia, brain injury evolves over three main phases (latent, secondary and tertiary), each with a different brain energy, perfusion, neurochemical and inflammatory milieu. While therapeutic hypothermia has targeted the latent and secondary phase, we now need therapies that cover the continuum of brain injury that spans hours, days, weeks and months after the initial event. Most agents have several therapeutic actions but can be broadly classified under a predominant action (e.g., free radical scavenging, anti-apoptotic, anti-inflammatory, neuroregeneration, and vascular effects). Promising early/secondary phase therapies include Allopurinol, Azithromycin, Exendin-4, Magnesium, Melatonin, Noble gases and Sildenafil. Tertiary phase agents include Erythropoietin, Stem cells and others. We review a selection of promising therapeutic agents on the translational pipeline and suggest a framework for neuroprotection and neurorestoration that targets the evolving injury.

Effects of Hypothermia and Allopurinol on Oxidative Status in a Rat Model of Hypoxic Ischemic Encephalopathy

Hypoxic ischemic encephalopathy (HIE) is one of the main causes of morbidity and mortality during the neonatal period, despite treatment with hypothermia. There is evidence that oxidative damage plays an important role in the pathophysiology of hypoxic-ischemic (HI) brain injury. Our aim was to investigate whether postnatal allopurinol administration in combination with hypothermia would reduce oxidative stress (OS) biomarkers in an animal model of HIE. Postnatal 10-day rat pups underwent unilateral HI of moderate severity. Pups were randomized into: Sham operated, hypoxic-ischemic (HI), HI + allopurinol (HIA), HI + hypothermia (HIH), and HI + hypothermia + allopurinol (HIHA). Biomarkers of OS and antioxidants were evaluated: GSH/GSSG ratio and carbonyl groups were tested in plasma. Total antioxidant capacity (TAC) was analyzed in plasma and cerebrospinal fluid, and 8-iso-prostaglandin F2α was measured in brain tissue. Plasma 2,2′–azinobis-(3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) levels were preserved in those groups that received allopurinol and dual therapy. In cerebrospinal fluid, only the HIA group presented normal ferric reducing ability of plasma (FRAP) levels. Protein oxidation and lipid peroxidation were significantly reduced in all groups treated with hypothermia and allopurinol, thus enhancing neuroprotection in HIE.

Mitochondrial dysfunction in perinatal asphyxia: role in pathogenesis and potential therapeutic interventions

Perinatal asphyxia (PA)-induced brain injury may present as hypoxic-ischemic encephalopathy in the neonatal period, and long-term sequelae such as spastic motor deficits, intellectual disability, seizure disorders and learning disabilities. The brain injury is secondary to both the hypoxic-ischemic event and oxygenation-reperfusion following resuscitation. Following PA, a time-dependent progression of neuronal insult takes place in terms of transition of cell death from necrosis to apoptosis. This transition is the result of time-dependent progression of pathomechanisms which involve excitotoxicity, oxidative stress, and ultimately mitochondrial dysfunction in developing brain. More precisely mitochondrial respiration is suppressed and calcium signalling is dysregulated. Consequently, Bax-dependent mitochondrial permeabilization occurs leading to release of cytochrome c and activation of caspases leading to transition of cell death in developing brain. The therapeutic window lies within this transition process. At present, therapeutic hypothermia (TH) is the only clinical treatment available for treating moderate as well as severe asphyxia in new-born as it attenuates secondary loss of high-energy phosphates (ATP) (Solevåg et al. in Free Radic Biol Med 142:113-122, 2019; Gunn et al. in Pediatr Res 81:202-209, 2017), improving both short- and long-term outcomes. Mitoprotective therapies can offer a new avenue of intervention alone or in combination with therapeutic hypothermia for babies with birth asphyxia. This review will explore these mitochondrial pathways, and finally will summarize past and current efforts in targeting these pathways after PA, as a means of identifying new avenues of therapeutic intervention.

Fetal Neuroprotective Strategies: Therapeutic Agents and Their Underlying Synaptic Pathways

Synaptic signaling is integral for proper brain function. During fetal development, exposure to inflammation or mild hypoxic-ischemic insult may lead to synaptic changes and neurological damage that impairs future brain function. Preterm neonates are most susceptible to these deleterious outcomes. Evaluating clinically used and novel fetal neuroprotective measures is essential for expanding treatment options to mitigate the short and long-term consequences of fetal brain injury. Magnesium sulfate is a clinical fetal neuroprotective agent utilized in cases of imminent preterm birth. By blocking N-methyl-D-aspartate receptors, magnesium sulfate reduces glutamatergic signaling, which alters calcium influx, leading to a decrease in excitotoxicity. Emerging evidence suggests that melatonin and N-acetyl-L-cysteine (NAC) may also serve as novel putative fetal neuroprotective candidates. Melatonin has important anti-inflammatory and antioxidant properties and is a known mediator of synaptic plasticity and neuronal generation. While NAC acts as an antioxidant and a precursor to glutathione, it also modulates the glutamate system. Glutamate excitotoxicity and dysregulation can induce perinatal preterm brain injury through damage to maturing oligodendrocytes and neurons. The improved drug efficacy and delivery of the dendrimer-bound NAC conjugate provides an opportunity for enhanced pharmacological intervention. Here, we review recent literature on the synaptic pathways underlying these therapeutic strategies, discuss the current gaps in knowledge, and propose future directions for the field of fetal neuroprotective agents.

Implanting melatonin at lambing enhances lamb growth and maintains high fat content in milk

Three experiments were designed to study the effects of melatonin implantation of ewes and lambs after lambing on the growth of lambs and milk quality throughout lactation. In experiment 1, 53 lambs either did (n = 28) or did not (n = 25) receive a subcutaneous 18-mg melatonin implant at the base of the left ear. In experiment 2, 55 lambs and their mothers either did (lambs: n = 28; ewes: n = 15) or did not (lambs: n = 27; ewes: n = 16) receive a melatonin implant. Milk samples were collected at 15, 30, and 45 d after lambing. In experiment 3, 16 lambs were separated from their mothers 24 h after birth, moved to an artificial rearing unit, and either did (n = 9) or did not (n = 7) receive a melatonin implant. In the three experiments, implants were inserted 24 h after lambing, and lambs were weighed (LW) weekly until weaning (for each experiment, 7, 6, and 5 wk., respectively). Average daily gains (ADG) from birth to weaning were calculated. Melatonin treatment of lambs did not have a significant effect on LW at weaning or ADG, but lambs reared by implanted ewes in experiment 2 presented higher (P < 0.05) LW (±S.E.M.) at weaning (implanted: 13.61 ± 0.51; non-implanted: 12.09 ± 0.57 kg) and ADG (implanted: 221.00 ± 10.45; non-implanted: 189.92 ± 12.44 g/d) than did lambs reared by control ewes. At day 45 of lactation, milk fat and total solid content were higher (P < 0.05) in implanted ewes than they were in control ewes. Groups did not differ significantly in the protein and lactose content of their milk. In conclusion, melatonin treatment of ewes at lambing induced a high growth rate of their lambs and increased the fat content of the milk; however, the direct treatment with melatonin of the lambs at birth did not have an effect in their growth rate.

Melatonin for Neonatal Encephalopathy: From Bench to Bedside

Neonatal encephalopathy is a leading cause of morbidity and mortality worldwide. Although therapeutic hypothermia (HT) is now standard practice in most neonatal intensive care units in high resource settings, some infants still develop long-term adverse neurological sequelae. In low resource settings, HT may not be safe or efficacious. Therefore, additional neuroprotective interventions are urgently needed. Melatonin's diverse neuroprotective properties include antioxidant, anti-inflammatory, and anti-apoptotic effects. Its strong safety profile and compelling preclinical data suggests that melatonin is a promising agent to improve the outcomes of infants with NE. Over the past decade, the safety and efficacy of melatonin to augment HT has been studied in the neonatal piglet model of perinatal asphyxia. From this model, we have observed that the neuroprotective effects of melatonin are time-critical and dose dependent. Therapeutic melatonin levels are likely to be 15-30 mg/L and for optimal effect, these need to be achieved within the first 2-3 h after birth. This review summarises the neuroprotective properties of melatonin, the key findings from the piglet and other animal studies to date, and the challenges we face to translate melatonin from bench to bedside.

Emerging therapies and management for neonatal encephalopathy-controversies and current approaches

Neonatal encephalopathy (NE) continues to have a major impact on newborn survival and neurodevelopmental outcomes worldwide. In high-income settings, therapeutic hypothermia is the only established standard treatment for neonates with moderate-to-severe NE, with compelling evidence that cooling reduces mortality and major neurodevelopmental impairment in survivors. Despite therapeutic hypothermia, a significant proportion of cooled infants continue to suffer long-term disability from brain injury. Innovative therapies offer the possibility of further improving neurodevelopmental outcomes by working synergistically with therapeutic hypothermia to decrease hypoxia-ischemia-induced excitotoxicity, prevent progression to secondary energy failure, and in some cases, promote neuroregeneration in the developing neonatal brain. This review discusses emerging NE therapies currently under investigation, offers insight into controversies surrounding various approaches to clinical care during therapeutic hypothermia, and identifies ongoing knowledge deficits that hinder attainment of optimal outcomes for neonates with NE.