Neuroprotective Role of Lactoferrin during Early Brain Development and Injury through Lifespan

The shifting landscape of the preterm brain

Preterm birth remains a significant global health concern despite advancements in neonatal care. While survival rates have increased, the long-term neurodevelopmental consequences of preterm birth persist. Notably, the profile of the preterm infant has shifted, with infants at earlier gestational ages surviving and decreased rates of gross structural injury secondary to intracranial hemorrhage. However, these infants are still vulnerable to insults, including hypoxia-ischemia, inflammation, and disrupted in utero development, impinging on critical developmental processes, which can lead to neuronal and oligodendrocyte injury and impaired brain function. Consequently, preterm infants often experience a range of neurodevelopmental disorders, such as cognitive impairment and behavioral problems. Here, we address mechanisms underlying preterm brain injury and explore existing and new investigational therapeutic strategies. We discuss how gestational age influences brain development and how interventions, including pharmacological and non-pharmacological approaches, mitigate the effects of preterm birth complications and improve the long-term outcomes of preterm infants.

Effect of A1 protein-free formula versus conventional formula on acute respiratory infections and diarrhea in toddlers: A Randomized Controlled Trial

OBJECTIVES

Acute respiratory infections (ARIs) and diarrhea are common in toddlers. Milk free of A1 β-casein (A1PF milk) may support the immune system, but few studies have investigated A1PF milk in toddler formula and any potential effects on ARI/diarrhea. This study's objective was to investigate the incidence of ARI and diarrhea with two toddler formulas, A1PF formula (A1PF) or conventional formula (CON), which differed in milk base and nutrient composition.

METHODS

This randomized, open-label, multicenter study (19 December 2022 to 17 May 2023) evaluated the occurrence of ARI and/or diarrhea in toddlers (aged 2-3 years) who consumed A1PF or CON over 90 days.

RESULTS

A total of 200 toddlers were enrolled, and 180 completed the study. The relative risk of ARI or diarrhea in the A1PF group versus the CON group did not differ significantly, but the median (interquartile range) ARI duration was significantly shorter in the A1PF group (3 [2-4] days vs. 5 [3-6] days, p = 0.012). At Day 90, toddlers consuming A1PF had significantly less severe bloating, gassiness, and fewer regurgitation events (all p < 0.05). Both formulas were well tolerated, and no serious adverse events were reported.

CONCLUSION

Toddlers who consumed A1PF had a reduced duration of ARI and improved diarrhea outcomes, reducing the burden on their families compared with toddlers who consumed CON. Although this is consistent with other studies, further research is required to determine whether these effects are solely attributable to the A1PF milk base or other differences between the formulas.

Maternal lactoferrin supplementation prevents mitochondrial and redox homeostasis dysfunction, and improves antioxidant defenses through Nrf2 and UCP2 signaling after neonatal hypoxia-ischemia

Neonatal hypoxia-ischemia (HI) is a major cause of mortality and neurological impairments in infants. Main HI-induced pathological mechanisms include mitochondrial dysfunction and oxidative stress due to insufficient oxygen and energetic substrates to the nervous cells. Bovine lactoferrin (Lf) has demonstrated neuroprotective effects in several experimental models of neonatal brain injury in rodents, however its mechanisms remain unclear. This study aimed to evaluate the early impact of maternal dietary supplementation with Lf on redox and hippocampal mitochondrial function following neonatal HI. From postnatal day 6 (PND6), pregnant Wistar rats were fed with a diet supplemented with Lf (1 g/kg) or with an isocaloric control diet until offspring euthanasia. At PND7, pups of both sexes were subjected to experimental HI through the occlusion of the right common carotid artery followed by 60 min of hypoxia (8 % oxygen). Lf prevented HI-induced increased levels of DCFH and lipoperoxidation in hippocampus. Furthermore, Lf enhanced antioxidant defenses including SOD, GPx, and GSH, counteracting HI-induced oxidative stress. HI injury altered the activities of enzymes in the mitochondrial respiratory chain and increased the mitochondrial membrane potential. Both effects were counteracted by Lf supplementation. Lactoferrin prevented oxidative stress and to restored mitochondrial function by upregulating Nrf2 and UCP2 expression following experimental HI. Our results show that even a shorter period of Lf delivery to rat pups is able to improve hippocampal response to neonatal hypoxia-ischemia, reversing initial mechanisms of damage in the cascade of HI injury.

Molecular Characterization and Expression of Lactoferrin Receptor (LfR) in Different Regions of the Brain Responding to Lactoferrin Intervention

Lactoferrin (LF), an iron-binding glycoprotein rich in human milk, promotes neurodevelopment and cognition, but whether it acts through the LF receptor (LfR) and its expression profile in the brain remains unknown. We characterized 972 bp of piglet brain LfR cDNA and found LfR mRNA was expressed all brain regions being highest in the frontal lobe, followed by parietal lobe, brainstem, occipital lobe, cingulate gyrus, subventricular zone, olfactory bulb, hippocampus, amygdala, cerebellum, and thalamus. LfR mRNA and protein in different regions of the brain responded to low (155 mg/kg/day) and high (285 mg/kg/day) LF supplementation of piglets from postnatal days 3 to 38. By postnatal day 39, the low LF diet significantly increased LfR protein expression in the occipital lobe compared to controls, but not the high LF diet. LfR protein in the subventricular zone of the high LF group was 42% and 38% higher than that of the low LF group and controls, respectively. There was a trend for a dose-response relationship between LF intervention and LfR protein expression only in the prefrontal and parietal lobes. LF supplementation significantly improved piglet working memory for a difficult task, which was positively correlated with LfR protein in the prefrontal, parietal, and occipital lobes, but no dose response. Brain LfR responds to dietary LF supplementation, a mechanism by which LF can promote learning and working memory through its receptor. LfR is expressed in the whole brain, and its expression level is anatomic region specific.

Effects of maternal-offspring supplementation of probiotics and synbiotics on the immunity of offspring Bama mini-pigs

Maternal nutrition is one of the main factors regulating the growth and immunity of piglets. This study aimed to investigate the effects of maternal or maternal-offspring supplementation of antibiotics, probiotics, and synbiotics on the immunity of offspring (21, 65, and 125 day-old) in Bama mini-pigs. The results showed that adding antibiotics to maternal diets increased the plasma IFN-γ level of offspring piglets at 21 day-old. Compared with maternal supplementation, maternal-offspring supplementation of antibiotics decreased the IL-10 level in the spleen, probiotics decreased IL-2, IL-10, and TNF-α levels in the ileum, and synbiotics decreased IL-10 and IFN-γ levels in the ileum of offspring piglets. Moreover, maternal-offspring antibiotics supplementation increased the IL-1β level in the ileum, while probiotics supplementation increased the IL-1β level in the spleen of offspring piglets. Maternal antibiotics supplementation increased the TNF-α level in the ileum at 95 day-old compared with maternal probiotics and synbiotics supplementation. Maternal-offspring antibiotics supplementation increased the IL-1β level in the ileum compared with the probiotics supplementation, while synbiotics supplementation increased the IL-6 level in the ileum than the probiotics and antibiotics supplementation at 95 day-old. Moreover, maternal-offspring probiotics supplementation increased the IL-1β level in the spleen of offspring pigs, which was higher than the maternal probiotics supplementation. These findings suggest that the immune function of the offspring piglets varied depending on the specific approach used for probiotics and synbiotics supplementation.

Lactoferrin alleviates the adverse effects of early-life inflammation on depression in adults by regulating the activation of microglia

Lactation is a crucial phase of brain development, and the events and nutrients during this period have long-term consequences for the occurrence of depression. This study investigated the effect and mechanism of lactoferrin (LF) deficiency during lactation on depression in adulthood. Lactation LF-deficient mice were established by nursing wild-type mice using LF systemic knockout mother mice. Additionally, 14-day-old mice were injected with lipopolysaccharide (LPS) and subjected to chronic unpredictable mild stress when they reached 6 weeks of age. The results show that lactation lactoferrin deficiency increases depression-like behavior in adult mice, and the mechanism is associated with heightened neuronal damage, abnormal microglial activation, and decreased BDNF in the hippocampus. In contrast, recombinant human lactoferrin promotes neuronal proliferation by upregulating ERK 1 and 2 phosphorylation and attenuates LPS-induced neuronal injury and microglial activation by inhibiting the activation of Toll-like receptor 4-nuclear factor-kappa B pathway in vitro. Our findings suggest that lactoferrin intake during lactation protects neurons by regulating microglial activation, thereby effectively reducing depressive symptoms in adults.

Evaluating neuronal damage biomarkers at birth for predicting neurodevelopmental risks in foetal growth restriction

AIM

This study was based on the need to predict neurodevelopmental outcomes of children with foetal growth restriction. The aim was to systematically review the correlation between biomarkers of neural injury in children with foetal growth restriction and their neurodevelopment.

METHOD

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, the review included studies on growth-restricted foetuses that measured biomarkers of postpartum brain injury and assessed neurodevelopment in childhood. Studies published between 1 January 2014 and 31 March 2024 were identified through PubMed and Embase, with the study protocol registered in PROSPERO (CRD42024520254).

RESULTS

Only five met the inclusion criteria. Results showed that urinary S100B levels were significantly elevated in foetal growth restriction, negatively correlating with neurological development at 7 days of life. Neuron-specific enolase negatively correlated with cognitive, motor and socio-emotional development. Urinary nerve growth factor levels were significantly lower in neonates with foetal growth restriction, correlating with poor neurodevelopment. No alterations in BDNF levels were observed. Tau protein levels were lower in children with foetal growth restriction and adverse outcomes.

CONCLUSION

The study emphasised the need for further research on biomarkers and predictive models of neurodevelopment in children with foetal growth restriction.

Lactoferrin Attenuates Pro-Inflammatory Response and Promotes the Conversion into Neuronal Lineages in the Astrocytes

Neurodegenerative diseases are characterized by progressive loss of neurons and persistent inflammation. Neurons are terminally differentiated cells, and lost neurons cannot be replaced since neurogenesis is restricted to only two neurogenic niches in the adult brain, whose neurogenic potential decreases with age. In this regard, the astrocytes reprogramming into neurons may represent a promising strategy for restoring the lost neurons and rebuilding neural circuits. To date, many anti-inflammatory agents have been shown to reduce neuroinflammation; however, their potential to restore neuronal loss was poorly investigated. This study investigates the anti-inflammatory effects of lactoferrin on DI-TNC1 astrocyte cell line and its ability to induce astrocyte reprogramming in a context of sustained inflammation. For this purpose, astrocytes were pre-treated with lactoferrin (4 μg/mL) for 24 h, then with lipopolysaccharide (LPS) (400 ng/mL), and examined 2, 9 and 16 days from treatment. The results demonstrate that lactoferrin attenuates astrocyte reactivity by reducing Toll-like receptor 4 (TLR4), Glial fibrillary acidic protein (GFAP) and IL-6 expression, as well as by upregulating Interleukin-10 (IL-10) cytokine and NRF2 expression. Moreover, lactoferrin promotes the reprogramming of reactive astrocytes into proliferative neuroblasts by inducing the overexpression of the Sex determining region Y/SRY-box 2 (SOX2) reprogramming transcription factor. Overall, this study highlights the potential effects of lactoferrin to attenuate neuroinflammation and improve neurogenesis, suggesting a future strategy for the treatment of neurodegenerative disorders.

The Association of Serum Lactoferrin Level with Psychological Symptoms, Cognition, and Executive Function in Schizophrenia Patients

Objective: Lactoferrin, a glycoprotein, has known neuroprotective effects, yet its role in the pathophysiology of neuropsychiatric disorders, particularly schizophrenia, remains unclear. This study aims to assess changes in lactoferrin levels during different phases of schizophrenia and explore its relationship with cognitive symptoms and performance. Method : This before/after interventional study involved 30 patients diagnosed with schizophrenia. Participants were evaluated at two time points: upon hospital admission and after the resolution of acute symptoms. The Positive and Negative Syndrome Scale (PANSS) was utilized to measure symptom severity, while the Brief Assessment of Cognition in Schizophrenia (BACS) assessed the neurocognitive function. Serum lactoferrin levels were quantified using the Enzyme-Linked Immunosorbent Assay (ELISA) method. Results: Serum lactoferrin levels significantly decreased from 130.63 ± 52.49 ng/mL at admission to 85.42 ± 29.03 ng/mL at discharge (P < 0.001). No significant correlation was found between lactoferrin levels and PANSS scores (r = 0.011, P = 0.975). However, an inverse correlation was observed between changes in lactoferrin levels and the executive function subscale of the BACS (r = -0.360, P = 0.050). Cognitive assessments indicated significant improvements in verbal memory (P = 0.033), working memory (P = 0.002), and executive function (P = 0.039) post-treatment. Conclusion: The study demonstrates a significant reduction in serum lactoferrin levels during the acute phase of schizophrenia, suggesting its potential role in modulating cognitive functions, particularly the executive function, rather than influencing positive or negative symptoms.

[Neonatal Malnutrition Impacts Fibroblast Growth Factor 21-induced Neurite Outgrowth and Growth Hormone-releasing Hormone Secretion in Neonatal Mouse Brain]

Neonatal malnutrition has been suggested as a factor contributing to neurological and other disorders. However, the details of this mechanism remain unclear. We focused on fibroblast growth factor 21 (FGF21), an endocrine factor produced in the liver during lactation-the main source of nutrition during the neonatal period- and analyzed its role in the brain. From the RNA-seq analysis of mouse brains, we analyzed the genes whose expression was regulated by FGF21 and their respective functions. We found that FGF21 has two functions in the neonatal brain; FGF21 induces the production of growth hormone-releasing hormone (GHRH) in the hypothalamus and is involved in isoform determination of Kalirin, a Ras homologous guanine nucleotide exchange factor, and promotes neurite outgrowth in the brain. Furthermore, the above mechanism is regulated by SH2-containing tyrosine phosphatase (SHP2) activity downstream of the FGF receptor. Additionally, the conserved intron of the SHP2 gene, Ptpn11, shows altered activity in malnourished mouse brains. In summary, FGF21 functions in neurite outgrowth and GHRH production in the neonatal mouse brain, with the mechanism being regulated by SHP2. However, SHP2 activity depends on nutritional status. Our goal was to elucidate the mechanisms by which FGF21 is involved in the maintenance of the central nervous system during the neonatal period. This study provides new insights into the role of FGF21 in diseases caused by dysfunction due to malnutrition.

Human milk whey proteins: Constituents, influencing factors, detection methods, and comparative analysis with other sources

Whey proteins, the most abundant proteins in human milk (HM), play a vital role in the growth and development of infants. This review first elaborates on the main components of HM whey proteins, including various proteins with specific functions, and details the functions of these proteins in terms of infant nutrition, immunity, as well as growth and development. Secondly, it analyzes factors that affect HM whey proteins, such as maternal differences, dietary habits, and geographical differences. Thirdly, it discusses detection methods for HM whey proteins, covering the principles, advantages, and limitations of different technical means. Finally, it compares whey proteins from different milk sources, highlighting their differences in composition, function, and characteristics. This review aims to comprehensively present the current research status of HM whey protein, provide a scientific basis for maternal and infant health, and contribute to optimizing infant feeding strategies and the research and development of related products.

Antioxidant Therapy in Neonatal Hypoxic Ischemic Encephalopathy: Adjuvant or Future Alternative to Therapeutic Hypothermia?

BACKGROUND

Oxidative stress-related diseases in newborns arise from pro-oxidant/antioxidant imbalance in both term and preterm neonates. Pro-oxidant/antioxidant imbalance has shown to be present in different pathological conditions such as hypoxic ischemic encephalopathy (HIE), retinopathy of prematurity (ROP), bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and patent ductus arteriosus (PDA).

METHODS AND RESULTS

We performed a narrative review according to the most recent available literature (2012-2024), using Scopus and PubMed as electronic databases. Many observational and experimental studies in vitro and in vivo have evaluated the effectiveness of antioxidant therapies such as melatonin, erythropoietin (EPO), allopurinol, N-acetylcisteine (NAS), and nitric oxide synthase (NOS) inhibitors in these diseases. Perinatal asphyxia is one of the most important causes of mortality and morbidity in term and near-term newborns. Therapeutic hypothermia (TH) is the gold standard treatment for neonates with moderate-severe perinatal asphyxia, resulting in a reduction in the mortality and neurodevelopmental disability rates.

CONCLUSIONS

According to the most recent literature and clinical trials, melatonin, allopurinol, NAS, NOS inhibitors, magnesium sulfate, and stem cells stand out as promising as both adjuvants and future probable alternatives to TH in the treatment of HIE.

Investigating the modulatory effects of lactoferrin on depressed rats through 16S rDNA gene sequencing and LC-MS metabolomics analysis

Lactoferrin is a natural multifunctional glycoprotein with potential antidepressant-like effects. However, the mechanism of its antidepressant effect has not been explored from the perspective of gut flora metabolism. Therefore, we employed both 16S rDNA gene sequencing and LC-MS metabolomics analysis to investigate the regulatory effects and mechanisms of lactoferrin in a rat model of depression. After one week of acclimatization, twenty-four 7-week-old male Sprague-Dawley rats were randomly and equally assigned into three groups: the control group, the model group, and the lactoferrin intervention group. The control group rats were housed under standard conditions, while the rats in the model and lactoferrin intervention groups were individually housed and exposed to chronic unpredictable mild stress for 44 days simultaneously. The lactoferrin intervention group was provided with water containing 2% lactoferrin (2 g/100 ml). Behavioural tests were conducted at week 7. Upon completion of the behavioral tests, the rats were anesthetized with isoflurane, humanely euthanized using a rat guillotine, and tissue samples were collected for further experiments. The results indicated that lactoferrin intervention led to an increase in sucrose solution consumption, horizontal movement distance, number of cross platforms, and residence time in the target quadrant. Additionally, it resulted in an increase in jejunal tight junction protein ZO-1 expression and a suppression of serum expression of inflammatory factors, Lipopolysaccharide and Diamine oxidase. In summary, lactoferrin can regulate the metabolic disorder of intestinal flora, reduce intestinal permeability, and further regulate the metabolic balance of hippocampal tissues through the microbiota-gut-brain axis. This process ultimately alleviates the depression-like behavior in rats.

Diet Supplemented with Special Formula Milk Powder Promotes the Growth of the Brain in Rats

This investigation was to study the effects of different formula components on the brain growth of rats. Fifty male SD rats were randomly divided into five groups: a basic diet group; a 20% ordinary milk powder group; a 20% special milk powder group; a 30% ordinary milk powder group; and a 30% special milk powder group by weight. LC-MS was used to detect brain lipidomics. After 28 days of feeding, compared with the basic diet group, the brain/body weights of rats in the 30% ordinary milk powder group were increased. The serum levels of 5-HIAA in the 30% ordinary milk powder group were lower than in the 20% ordinary milk powder group. Compared with the basic diet group, the expressions of DLCL, MePC, PI, and GM1 were higher in the groups with added special milk powder, while the expressions of LPE, LdMePE, SM, and MGTG were higher in the groups with added ordinary milk powder. The expression of MBP was significantly higher in the 20% ordinary group. This study found that different formula components of infant milk powder could affect brain growth in SD rats. The addition of special formula infant milk powder may have beneficial effects on rat brains by regulating brain lipid expression.

Characterization of recombinant human lactoferrin expressed in Komagataella phaffii

This work presents a thorough characterization of Helaina recombinant human lactoferrin (rhLF, Effera™) expressed in a yeast system at an industrial scale for the first time. Proteomic analysis confirmed that its amino acid sequence is identical to that of native human LF. N-linked glycans were detected at three known glycosylation sites, namely, Asparagines-156, -497, and -642 and they were predominantly oligomannose structures having five to nine mannoses. Helaina rhLF's protein secondary structure was nearly identical to that of human milk lactoferrin (hmLF), as revealed by microfluidic modulation spectroscopy. Results of small-angle X-ray scattering (SAXS) and analytical ultracentrifugation analyses confirmed that, like hmLF, Helaina rhLF displayed well-folded globular structures in solution. Reconstructed solvent envelopes of Helaina rhLF, obtained through the SAXS analysis, demonstrated a remarkable fit with the reported crystalline structure of iron-bound native hmLF. Differential scanning calorimetry investigations into the thermal stability of Helaina rhLF revealed two distinct denaturation temperatures at 68.7 ± 0.9 °C and 91.9 ± 0.5 °C, consistently mirroring denaturation temperatures observed for apo- and holo-hmLF. Overall, Helaina rhLF differed from hmLF in the N-glycans they possessed; nevertheless, the characterization results affirmed that Helaina rhLF was of high purity and exhibited globular structures closely akin to that of hmLF.

Exploring the Role of Lactoferrin in Managing Allergic Airway Diseases among Children: Unrevealing a Potential Breakthrough

The prevalence of allergic diseases has dramatically increased among children in recent decades. These conditions significantly impact the quality of life of allergic children and their families. Lactoferrin, a multifunctional glycoprotein found in various biological fluids, is emerging as a promising immunomodulatory agent that can potentially alleviate allergic diseases in children. Lactoferrin's multifaceted properties make it a compelling candidate for managing these conditions. Firstly, lactoferrin exhibits potent anti-inflammatory and antioxidant activities, which can mitigate the chronic inflammation characteristic of allergic diseases. Secondly, its iron-binding capabilities may help regulate the iron balance in allergic children, potentially influencing the severity of their symptoms. Lactoferrin also demonstrates antimicrobial properties, making it beneficial in preventing secondary infections often associated with respiratory allergies. Furthermore, its ability to modulate the immune response and regulate inflammatory pathways suggests its potential as an immune-balancing agent. This review of the current literature emphasises the need for further research to elucidate the precise roles of lactoferrin in allergic diseases. Harnessing the immunomodulatory potential of lactoferrin could provide a novel add-on approach to managing allergic diseases in children, offering hope for improved outcomes and an enhanced quality of life for paediatric patients and their families. As lactoferrin continues to capture the attention of researchers, its properties and diverse applications make it an intriguing subject of study with a rich history and a promising future.

Composition of breast milk from mothers of premature and full-term infants and its influence in Z-Scores for infant physical growth

BACKGROUND

Breast milk contains various crucial nutrients and biologically active substances and is ideal for newborns. This study aimed to analyze the composition of breast milk from mothers of premature and full-term infants and its influences on the growth of infants.

METHODS

Infant-mother dyads examined at our Hospital (March 2016 to May 2017) were included. Milk was collected at 0-1 month, 2-3 months, and 5-6 months and analyzed using a MIRIS human milk analyzer. Z-scores of weight-for-length (WLZ), weight-for-age (WAZ), and length-for-age (LAZ) were calculated.

RESULTS

This study included full-term (> 37 weeks of gestation, n = 177) and premature (< 37 weeks, n = 94) infant-mother dyads. The premature infants showed higher ΔWAZ, ΔLAZ, and ΔWLZ from infancy to toddlerhood for the physical growth speed, compared with term infants (P < 0.001). All proteins and true protein components of breast milk decreased with infants' age (P < 0.001). For premature and full-term infants, differences in ΔWAZ and ΔLAZ from birth to infancy and the difference in ΔLAZ, WAZ, and LAZ in toddlerhood were positively associated with non-protein nitrogen (NPN) (all P < 0.05), while the Z-score differences in ΔWLZ from birth to infancy were negatively associated with NPN (all P < 0.05). For premature babies, from birth to infancy stage, ΔWAZ was positively correlated with NPN and carbohydrates while negatively correlated with dry matter (all P < 0.05), and ΔLAZ correlated with NPN (β = 0.428, P = 0.005).

CONCLUSION

Breastfeeding helped premature infants compensatory growth when compared to term infants. Whileduring early infancy stage ΔWLZ gain was negatively associated with increased amounts of NPN in breast milk. This might mean although NPN increase the Z-scores of weight-for-age and length-for-age, with no rise in adipose tissue mass.

Unlocking the power of Lactoferrin: Exploring its role in early life and its preventive potential for adult chronic diseases

Nutrition during the early postnatal period exerts a profound impact on both infant development and later-life health. Breast milk, which contains lactoferrin, a dynamic protein, plays a crucial role in the growth of various biological systems and in preventing numerous chronic diseases. Based on the relationship between early infant development and chronic diseases later in life, this paper presents a review of the effects of lactoferrin in early life on neonates intestinal tract, immune system, nervous system, adipocyte development, and early intestinal microflora establishment, as well as the preventive and potential mechanisms of early postnatal lactoferrin against adult allergy, inflammatory bowel disease, depression, cancer, and obesity. Furthermore, we summarized the application status of lactoferrin in the early postnatal period and suggested directions for future research.

Versatile Nanoparticulate Systems as a Prosperous Platform for Targeted Nose-Brain Drug Delivery

The intranasal route has proven to be a reliable and promising route for delivering therapeutics to the central nervous system (CNS), averting the blood-brain barrier (BBB) and avoiding extensive first-pass metabolism of some drugs, with minimal systemic exposure. This is considered to be the main problem associated with other routes of drug delivery such as oral, parenteral, and transdermal, among other administration methods. The intranasal route maximizes drug bioavailability, particularly those susceptible to enzymatic degradation such as peptides and proteins. This review will stipulate an overview of the intranasal route as a channel for drug delivery, including its benefits and drawbacks, as well as different mechanisms of CNS drug targeting using nanoparticulate drug delivery systems devices; it also focuses on pharmaceutical dosage forms such as drops, sprays, or gels via the nasal route comprising different polymers, absorption promoters, CNS ligands, and permeation enhancers.

Astrocyte-derived lactoferrin reduces β-amyloid burden by promoting the interaction between p38 kinase and PP2A phosphatase in male APP/PS1 transgenic mice

BACKGROUND AND PURPOSE

Overexpression of astrocytic lactoferrin (Lf) was observed in the brain of Alzheimer's disease (AD) patients, whereas the role of astrocytic Lf in AD progression remains unexplored. In this study, we aimed to evaluate the effects of astrocytic Lf on AD progression.

EXPERIMENTAL APPROACH

Male APP/PS1 mice with astrocytes overexpressing human Lf were developed to evaluate the effects of astrocytic Lf on AD progression. N2a-sw cells also were employed to further uncover the mechanism of astrocytic Lf on β-amyloid (Aβ) production.

KEY RESULTS

Astrocytic Lf overexpression increased protein phosphatase 2A (PP2A) activity and reduced amyloid precursor protein (APP) phosphorylation, Aβ burden and tau hyperphosphorylation in APP/PS1 mice. Mechanistically, astrocytic Lf overexpression promoted the uptake of astrocytic Lf into neurons in APP/PS1 mice, and conditional medium from astrocytes overexpressing Lf inhibited p-APP (Thr668) expression in N2a-sw cells. Furthermore, recombinant human Lf (hLf) significantly enhanced PP2A activity and inhibited p-APP expression, whereas inhibition of p38 or PP2A activities abrogated the hLf-induced p-APP down-regulation in N2a-sw cells. Additionally, hLf promoted the interaction of p38 and PP2A via p38 activation, thereby enhancing PP2A activity, and low-density lipoprotein receptor-related protein 1 (LRP1) knockdown significantly reversed the hLf-induced p38 activation and p-APP down-regulation.

CONCLUSIONS AND IMPLICATIONS

Our data suggested that astrocytic Lf promoted neuronal p38 activation, via targeting to LRP1, subsequently promoting p38 binding to PP2A to enhance PP2A enzyme activity, which finally inhibited Aβ production via APP dephosphorylation. In conclusion, promoting astrocytic Lf expression may be a potential strategy against AD.

LINKED ARTICLES

This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.

Early Neuroprotective Effects of Bovine Lactoferrin Associated with Hypothermia after Neonatal Brain Hypoxia-Ischemia in Rats

Neonatal hypoxic-ischemic (HI) encephalopathy (HIE) in term newborns is a leading cause of mortality and chronic disability. Hypothermia (HT) is the only clinically available therapeutic intervention; however, its neuroprotective effects are limited. Lactoferrin (LF) is the major whey protein in milk presenting iron-binding, anti-inflammatory and anti-apoptotic properties and has been shown to protect very immature brains against HI damage. We hypothesized that combining early oral administration of LF with whole body hypothermia could enhance neuroprotection in a HIE rat model. Pregnant Wistar rats were fed an LF-supplemented diet (1 mg/kg) or a control diet from (P6). At P7, the male and female pups had the right common carotid artery occluded followed by hypoxia (8% O2 for 60') (HI). Immediately after hypoxia, hypothermia (target temperature of 32.5-33.5 °C) was performed (5 h duration) using Criticool®. The animals were divided according to diet, injury and thermal condition. At P8 (24 h after HI), the brain neurochemical profile was assessed using magnetic resonance spectroscopy (1H-MRS) and a hyperintense T2W signal was used to measure the brain lesions. The mRNA levels of the genes related to glutamatergic excitotoxicity, energy metabolism and inflammation were assessed in the right hippocampus. The cell markers and apoptosis expression were assessed using immunofluorescence in the right hippocampus. HI decreased the energy metabolites and increased lactate. The neuronal-astrocytic coupling impairments observed in the HI groups were reversed mainly by HT. LF had an important effect on astrocyte function, decreasing the levels of the genes related to glutamatergic excitotoxicity and restoring the mRNA levels of the genes related to metabolic support. When combined, LF and HT presented a synergistic effect and prevented lactate accumulation, decreased inflammation and reduced brain damage, pointing out the benefits of combining these therapies. Overall, we showed that through distinct mechanisms lactoferrin can enhance neuroprotection induced by HT following neonatal brain hypoxia-ischemia.

Key players in the regulation of iron homeostasis at the host-pathogen interface

Iron plays a crucial role in the biochemistry and development of nearly all living organisms. Iron starvation of pathogens during infection is a striking feature utilized by a host to quell infection. In mammals and some other animals, iron is essentially obtained from diet and recycled from erythrocytes. Free iron is cytotoxic and is readily available to invading pathogens. During infection, most pathogens utilize host iron for their survival. Therefore, to ensure limited free iron, the host's natural system denies this metal in a process termed nutritional immunity. In this fierce battle for iron, hosts win over some pathogens, but others have evolved mechanisms to overdrive the host barriers. Production of siderophores, heme iron thievery, and direct binding of transferrin and lactoferrin to bacterial receptors are some of the pathogens' successful strategies which are highlighted in this review. The intricate interplay between hosts and pathogens in iron alteration systems is crucial for understanding host defense mechanisms and pathogen virulence. This review aims to elucidate the current understanding of host and pathogen iron alteration systems and propose future research directions to enhance our knowledge in this field.

Neonatal malnutrition impacts fibroblast growth factor 21-induced neuron neurite outgrowth and growth hormone-releasing hormone secretion in neonatal mouse brain

Neonatal malnutrition is one of the most common causes of neurological disorders. However, the mechanism of action of the factors associated with neonatal nutrition in the brain remains unclear. In this study, we focused on fibroblast growth factor (FGF) 21 to elucidate the effects of malnutrition on the neonatal brain. FGF21 is an endocrine factor produced by the liver during lactation which is the main source of nutrition during the neonatal period. In this study, malnourishment during nursing mice induced decreased levels of Fgf21 mRNA in the liver and decreased levels of FGF21 in the serum. RNA-seq analysis of neonatal mouse brain tissue revealed that FGF21 controlled the expression of Kalrn-201 in the neonatal mouse brain. Kalrn-201 is a transcript of Kalirin, a Ras homologous guanine nucleotide exchange factor at the synapse. In mouse neurons, FGF21 induced the expression of Kalirin-7 (a Kalirin isoform) by down-regulating Kalrn-201. FGF21-induced Kalirin-7 stimulated neurite outgrowth in Neuro-2a cells. FGF21 also induced Growth hormone-releasing hormone (GHRH) expression in Neuro-2a cells. Kalirin-7 and GHRH expression induced by FGF21 was altered by inhibiting the activity of SH2-containing tyrosine phosphatase (SHP2) which is located downstream of the FGF receptor (FGFR). Additionally, malnourished nursing induced intron retention of the SHP2 gene (Ptpn11), resulting in the alteration of Kalirin-7 and GHRH expression by FGF21 signaling. Ptpn11 intron retention is suggested to be involved in regulating SHP2 activity. Taken together, these results suggest that FGF21 plays a critical role in the induction of neuronal neurite outgrowth and GHRH secretion in the neonatal brain, and this mechanism is regulated by SHP2. Thus, Ptpn11 intron retention induced by malnourished nursing may be involved in SHP2 activity.

Anti-Inflammatory and Anti-Allergic Properties of Colostrum from Mothers of Full-Term and Preterm Babies: The Importance of Maternal Lactation in the First Days

Our narrative review focuses on colostrum components, particularly those that influence the neonatal immune system of newborns. Colostrum is secreted in small volumes by the alveolar cells of the breast during the first two to five days after birth. Colostrum is poor in fat and carbohydrates, with larger protein and bioactive compounds than mature milk. It plays a crucial role in driving neonates' immunity, transferring those immunological factors which help the correct development of the neonatal immune system and support establishing a healthy gut microbiome. The newborn has an innate and adaptive immune system deficiency, with a consequent increase in infection susceptibility. In particular, neonates born prematurely have reduced immunological competencies due to an earlier break in the maternal trans-placenta transfer of bioactive components, such as maternal IgG antibodies. Moreover, during pregnancy, starting from the second trimester, maternal immune cells are conveyed to the fetus and persist in small quantities post-natal, whereby this transfer is known as microchimerism (MMc). Thus, preterm newborns are deficient in this maternal heritage, and have their own immune system under-developed, but colostrum can compensate for the lack. Early breastfeeding, which should be strongly encouraged in mothers of preterm and full-term babies, provides those immunomodulant compounds that can act as a support, allowing the newborn to face immune needs, including fronting infections and establishing tolerance. Moreover, making mothers aware that administering colostrum helps their infants in building a healthy immune system is beneficial to sustain them in the difficult post-partum period.

Optimization of Nutrition after Brain Injury: Mechanistic and Therapeutic Considerations

Emerging science continues to establish the detrimental effects of malnutrition in acute neurological diseases such as traumatic brain injury, stroke, status epilepticus and anoxic brain injury. The primary pathological pathways responsible for secondary brain injury include neuroinflammation, catabolism, immune suppression and metabolic failure, and these are exacerbated by malnutrition. Given this, there is growing interest in novel nutritional interventions to promote neurological recovery after acute brain injury. In this review, we will describe how malnutrition impacts the biomolecular mechanisms of secondary brain injury in acute neurological disorders, and how nutritional status can be optimized in both pediatric and adult populations. We will further highlight emerging therapeutic approaches, including specialized diets that aim to resolve neuroinflammation, immunodeficiency and metabolic crisis, by providing pre-clinical and clinical evidence that their use promotes neurologic recovery. Using nutrition as a targeted treatment is appealing for several reasons that will be discussed. Given the high mortality and both short- and long-term morbidity associated with acute brain injuries, novel translational and clinical approaches are needed.

Lactoferrin Modulates Induction of Transcription Factor c-Fos in Neuronal Cultures

Lactoferrin (Lf) is a multifunctional protein from the transferrin family. Of particular interest is the ability of Lf to affect a wide range of neuronal processes by modulating the expression of genes involved in long-term neuroplasticity. The expression of the immediate early gene c-fos that is rapidly activated in response to external influences, and its product, transcription factor c-Fos, is widely used as a marker of long-term neuronal plasticity. The present study aims to examine the effect of human Lf on the induction of transcription factor c-Fos in the primary mouse neuronal cultures after stimulation and to determine the cellular localization of human Lf and its colocalization with induced c-Fos protein. Primary dissociated cultures of hippocampal cells were obtained from the brains of newborn C57BL/6 mice (P0-P1). On day 7 of culturing, human Lf was added to the medium. After 24 h (day 8 in culture), c-Fos protein was induced in cells by triple application of 50 mM KCl. c-Fos content was analyzed using the immunofluorescent method 2 h after stimulation. Stimulation promoted exogenous Lf translocation into the nuclei of cultured neuronal cells, which correlated with increased induction of transcription factor c-Fos and was accompanied by nuclear colocalization of these proteins. These results attest to the potential of Lf as a modulator of neuronal processes and open up new prospects in studying the mechanisms of the regulatory effects of lactoferrin on cell function.

Iron Saturation Drives Lactoferrin Effects on Oxidative Stress and Neurotoxicity Induced by HIV-1 Tat

The Trans-Activator of Transcription (Tat) of Human Immunodeficiency Virus (HIV-1) is involved in virus replication and infection and can promote oxidative stress in human astroglial cells. In response, host cells activate transcription of antioxidant genes, including a subunit of System Xc- cystine/glutamate antiporter which, in turn, can trigger glutamate-mediated excitotoxicity. Here, we present data on the efficacy of bovine Lactoferrin (bLf), both in its native (Nat-bLf) and iron-saturated (Holo-bLf) forms, in counteracting oxidative stress in U373 human astroglial cells constitutively expressing the viral protein (U373-Tat). Our results show that, dependent on iron saturation, both Nat-bLf and Holo-bLf can boost host antioxidant response by up-regulating System Xc- and the cell iron exporter Ferroportin via the Nuclear factor erythroid 2-related factor (Nrf2) pathway, thus reducing Reactive Oxygen Species (ROS)-mediated lipid peroxidation and DNA damage in astrocytes. In U373-Tat cells, both forms of bLf restore the physiological internalization of Transferrin (Tf) Receptor 1, the molecular gate for Tf-bound iron uptake. The involvement of astrocytic antioxidant response in Tat-mediated neurotoxicity was evaluated in co-cultures of U373-Tat with human neuronal SH-SY5Y cells. The results show that the Holo-bLf exacerbates Tat-induced excitotoxicity on SH-SY5Y, which is directly dependent on System-Xc- upregulation, thus highlighting the mechanistic role of iron in the biological activities of the glycoprotein.

Colostrum Proteins in Protection against Therapy-Induced Injuries in Cancer Chemo- and Radiotherapy: A Comprehensive Review

In this article, we review the benefits of application of colostrum and colostrum-derived proteins in animal models and clinical trials that include chemotherapy with antimetabolic drugs, radiotherapy and surgical interventions. A majority of the reported investigations was performed with bovine colostrum (BC) and native bovine or recombinant human lactoferrin (LF), applied alone, in nutraceutics or in combination with probiotics. Apart from reducing side effects of the applied therapeutics, radiation and surgical procedures, BC and LF augmented their efficacy and improved the wellness of patients. In conclusion, colostrum and colostrum proteins, preferably administered with probiotic bacteria, are highly recommended for inclusion to therapeutic protocols in cancer chemo- and radiotherapy as well as during the surgical treatment of cancer patients.