Lactoferrin, a key molecule in immune and inflammatory processes

Functional consequence of Iron dyshomeostasis and ferroptosis in systemic lupus erythematosus and lupus nephritis

Systemic lupus erythematosus (SLE) and its renal manifestation Lupus nephritis (LN) are characterized by a dysregulated immune system, autoantibodies, and injury to the renal parenchyma. Iron accumulation and ferroptosis in the immune effectors and renal tubules are recently identified pathological features in SLE and LN. Ferroptosis is an iron dependent non-apoptotic form of regulated cell death and ferroptosis inhibitors have improved disease outcomes in murine models of SLE, identifying it as a novel druggable target. In this review, we discuss novel mechanisms by which iron accumulation and ferroptosis perpetuate immune cell mediated pathology in SLE/LN. We highlight intra-renal dysregulation of iron metabolism and ferroptosis as an underlying pathogenic mechanism of renal tubular injury. The basic concepts of iron biology and ferroptosis are also discussed to expose the links between iron, cell metabolism and ferroptosis, that identify intracellular pro-ferroptotic enzymes and their protein conjugates as potential targets to improve SLE/LN outcomes.

Bovine lactoferrin inhibits inflammatory response and apoptosis in lipopolysaccharide-induced acute lung injury by targeting the PPAR-γ pathway

BACKGROUND

Lactoferrin (LF) is an iron-binding multifunctional cationic glycoprotein. Previous studies have demonstrated that LF may be a potential drug for treating acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In this study, we explored the anti-inflammatory effect and mechanism of bovine lactoferrin (bLF) in ALI using the RNA sequencing (RNA-seq) technology and transcriptome analysis.

METHODS AND RESULTS

Based on the differentially expressed genes (DEGs) obtained from RNA-seq of the Lung from mouse model, the bioinformatics workflow was implemented using the BGISEQ-500 platform. The protein-protein interaction (PPI) network was obtained using STRING, and the hub gene was screened using Cytoscape. To verify the results of transcriptome analysis, the effects of bLF on Lipopolysaccharide (LPS)-induced BEAS-2B cells and its anti-reactive oxygen species (ROS), anti-inflammatory, and antiapoptotic effects were studied via Cell Counting Kit-8 (CCK-8) test, active oxygen detection test, ELISA, and western blot assay. Transcriptome analysis revealed that two hub gene modules of DEGs were screened via PPI analysis using the STRING and MCODE plug-ins of Cytoscape. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that these core modules are enriched in the PPAR (peroxisome proliferator-activated receptor) and AMPK (AMP-activated protein kinase) signaling pathways. Through cell experiments, our study shows that bLF can inhibit ROS, inflammatory reaction, and LPS-induced BEAS-2B cell apoptosis, which are significantly antagonized by the PPAR-γ inhibitor GW9662.

CONCLUSION

This study has suggested that the PPAR-γ pathway is the critical target of bLF in anti-inflammatory reactions and apoptosis of ALI, which provides a direction for further research.

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.

Lactoferrin, the Moonlighting Protein of Innate Immunity

Lactoferrin (Lf), a naturally occurring glycoprotein involved in innate immunity, was first discovered in bovine milk [...].

L-ergothioneine reduces nitration of lactoferrin and loss of antibacterial activity associated with nitrosative stress

Lactoferrin (LF) is a multifunctional antimicrobial, anti-inflammatory, and antioxidant protein that occurs naturally in mammals, most notably in exocrine gland tissues and fluids, such as in the eye. Nitrosative stress can promote changes to tyrosine and other amino acid residues of the protein, which also reduces the activity of LF. l-ergothioneine (ET) is a potent anti-inflammatory antioxidant present in the eye and other tissues through nutrition or supplementation and that may play a role in the prevention or treatment of a variety of diseases. Here we investigated the ability of ET to reduce 3-nitrotyrosine (NTyr) formation using two separate substrates, with the goal of determining whether ET can protect the antibacterial function of LF and other proteins when exposed separately to peroxynitrite and tetranitromethane as nitrating reagents. Native human LF was used as a simple protein substrate, and lamb corneal lysate was chosen as one example of mammalian tissue with a more complex mixture of proteins and other biomolecules. Nitration was monitored by absorbance and fluorescence spectroscopy as well as sandwich (nitrated LF) and direct NTyr (corneal lysate) enzyme-linked immunosorbent assays (ELISAs). We found that pretreatment with ET reduced chemical modification of both native LF and corneal lysate samples and loss of antibacterial LF function due to exposure to the nitrating reagents. These initial results suggest that ET, raised to sufficiently elevated levels, could be tailored as a therapeutic agent to reduce effects of nitrosative stress on LF and in turn sustain the protein activity.

The influence of subclinical mastitis on the protein composition and protease activities of raw milk from lactating Thai-crossbred dairy cows

Background and Aim

Mastitis in dairy cattle is associated with a high rate of morbidity and death, which has major implications for milk production and quality. This study aimed to investigate the protein component and the activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in raw milk samples with different testing scores determined using the California mastitis test (CMT).

Materials and Methods

Thirty cows were employed in the study, and milk from each quarter was tested for subclinical mastitis (SCM). According to the results of CMT, raw milk samples were classified into five categories: Healthy (score 0), trace (score T), weakly positive (score 1), distinctly positive (score 2), and strongly positive (score 3) for somatic cell count (SCC). The total milk protein was analyzed using the Bio-Rad protein assay, and the milk protein composition was determined using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. In addition, gelatin zymography was used to evaluate changes in proteolytic abilities.

Results

Milk samples with CMT scores of 1 and 3 had the highest total milk protein levels (32.25 ± 12.60 g/L and 32.50 ± 7.67 g/L, respectively), while the samples from healthy cows (CMT score 0) were only 6.75 ± 1.64 g/L. Globulin and lactoferrin were significantly increased in samples with a CMT score of 3 compared with those with other CMT scores. The bovine serum albumin level in samples with a CMT score of 2 was significantly (p < 0.05) higher than those with other CMT scores. No significant differences in casein abundance were found among samples with different CMT scores. Results from analysis of proteolytic activities demonstrated that the level of MMP-9 in samples with a CMT score of 3 was significantly (p < 0.05) higher than those with other CMT scores.

Conclusion

The protein content and gelatinolytic activity of milk were drastically altered by the number of SCC, mainly due to SCM.

Myopia Is Suppressed by Digested Lactoferrin or Holo-Lactoferrin Administration

Myopia is becoming a leading cause of vision impairment. An effective intervention is needed. Lactoferrin (LF) is a protein that has been reported to inhibit myopia progression when taken orally. This study looked at the effects of different forms of LF, such as native LF and digested LF, on myopia in mice. Mice were given different forms of LF from 3 weeks of age, and myopia was induced with minus lenses from 4 weeks of age. Results showed that mice given digested LF or holo-LF had a less elongated axial length and thinned choroid, compared to those given native-LF. Gene expression analysis also showed that the groups given native-LF and its derivatives had lower levels of certain cytokines and growth factors associated with myopia. These results suggest that myopia can be more effectively suppressed by digested LF or holo-LF than native-LF.

Supplementation of broiler chicken diets with bovine lactoferrin improves growth performance, histological parameters of jejunum and immune-related gene expression

The aim of this study was to investigate the influence of dietary supplementation of bovine lactoferrin (bLF) on growth performance, carcass traits, histomorphology of jejunum, immune function and hepatic and splenic gene expression of interferon-gamma (IFN-γ) and interleukine-2 (IL-2) in broiler chickens. A total of 240 one-day-old Ross 308 male broiler chickens were randomly allotted into six dietary treatments with four replicate pens (10 chicks per pen) and fed experimental diet in 3 feeding phases (starter: d 0-10, grower: d 11-24 and finisher: d 25-42). The experimental treatments were (1) corn-soya bean meal-based basal diet (control), (2-5) basal diet supplemented with 200, 400, 600, 800 mg/kg bLF, respectively, and (6) basal diet supplemented with 200 mg/kg oxytetracycline (OTC). The average body weight gain (ABWG) of broilers fed 800 mg/kg bLF was 8.48% higher than those fed a corn-soybean meal-based diet during the starter period (d 0-10) (linear effect, p = 0.002; quadratic effect, p = 0.24). Average daily feed intake (ADFI) and the feed conversion ratio (FCR) were not affected (p>0.05) by bLF supplementation. At 42 days of age, the breast meat percentage and carcass yield of broilers fed 800 mg/kg bLF compared with the control group significantly increased by 9.51% and 6.03% respectively (p < 0.05). Compared with the chicks fed the control diet, the chicks fed diets supplemented with bLF had higher villus height, muscle thickness and villus surface area (p > 0.05). Dietary bLF inclusion increased the total immunoglobulin (IgT) titre against sheep red blood cells (SRBCs) antigen (linear effect, p = 0.031; quadratic effect, p = 0.035) and improved the phytohaemagglutinin-P (PHA-P)-skin test of broilers. Compared with the control, bLF enhanced the gene expression of IFN-γ in spleen (p = 0.048, linear effect, p = 0.009; quadratic effect, p = 0.093) and liver (p = 0.012, linear effect, p = 0.008; quadratic effect, p = 0.01) and IL-2 expression in spleen (p = 0.021, linear effect, p = 0.026; quadratic effect, p = 0.103). The bLF supplementation had no effect on IL-2 gene expression in liver (p > 0.05, linear effect, p = 0.213; quadratic effect, p = 0.159). In conclusion, we found that supplementation of broiler diets with 800 mg/kg bLF can improve the growth performance, carcass yield, cell-mediated and antibody-mediated immune responses and enhance the IL-2 and IFN-γ gene expression of broilers.

Antimicrobial Peptides with Rigid Linkers against Gram-Negative Bacteria by Targeting Lipopolysaccharide

A series of hybrid peptides were designed by connecting an antimicrobial peptide Ce(1-8) with a lipopolysaccharide (LPS)-targeting peptide Lf(28-34) via different linkers. Antimicrobial experimental results indicated that linkers play an essential role in the anti-Gram-negative bacterial activity of the hybrid peptides. Among these hybrid peptides, peptide CL5 with dipeptide rigid linker LP exhibited excellent activity and selectivity against Gram-negative bacteria. The minimum inhibitory concentrations of CL5 against the tested Gram-negative bacteria were 4-32 μM, while the toxicity toward HEK-293 cells was relatively low. It was found that the interactions of the peptides with LPS were crucial for peptide activity against Gram-negative bacteria. Antimicrobial mechanistic studies showed that peptide CL5 contributed to the death of Gram-negative bacterial cells by disrupting the integrity of the bacterial membranes. This study revealed the importance of linker selection in the design of hybrid peptides and provides the basis for the further development of antimicrobial peptides.

Can Lactoferrin, a Natural Mammalian Milk Protein, Assist in the Battle against COVID-19?

Notwithstanding mass vaccination against specific SARS-CoV-2 variants, there is still a demand for complementary nutritional intervention strategies to fight COVID-19. The bovine milk protein lactoferrin (LF) has attracted interest of nutraceutical, food and dairy industries for its numerous properties-ranging from anti-viral and anti-microbial to immunological-making it a potential functional ingredient in a wide variety of food applications to maintain health. Importantly, bovine LF was found to exert anti-viral activities against several types of viruses, including certain SARS-CoV-2 variants. LF's potential effect on COVID-19 patients has seen a rapid increase of in vitro and in vivo studies published, resulting in a model on how LF might play a role during different phases of SARS-CoV-2 infection. Aim of this narrative review is two-fold: (1) to highlight the most relevant findings concerning LF's anti-viral, anti-microbial, iron-binding, immunomodulatory, microbiota-modulatory and intestinal barrier properties that support health of the two most affected organs in COVID-19 patients (lungs and gut), and (2) to explore the possible underlying mechanisms governing its mode of action. Thanks to its potential effects on health, bovine LF can be considered a good candidate for nutritional interventions counteracting SARS-CoV-2 infection and related COVID-19 pathogenesis.

Effects of dietary supplementation of bovine lactoferrin on growth performance, immune function and intestinal health in weaning piglets

Weaning is a crucial period in the pig's life cycle, which is frequently followed by gastrointestinal (GI) infections, diarrhea and even death. This study focused on the impact of bovine lactoferrin (bLF) supplementation on the intestinal health of weaning piglets. Weaning piglets (Duroc × Landrace × Yorkshire, 23 days) were randomly allocated into four groups, which included negative control group (CON): basic diet; positive control group (ANT): basic diet + 20 mg/kg flavomycin + 100 mg/kg aureomycin; treatment group bLF-A: basic diet + 1 g/kg bLF; treatment group bLF-B: basic diet + 3 g/kg bLF. The result showed that dietary supplementation of bLF can improve growth performance and reduce diarrhea, which exhibits dose-dependency (P < 0.05). Compared with CON group, supplementation with bLF significantly improved immunity, and increased villus height and ratio of villus height/crypt depth at the small intestinal mucosa (P < 0.05). The mRNA expression of claudin-1, occludin and ZO-1 was greatly increased in the ileum of bLF group on days 7 and 14 (P < 0.05). Furthermore, the supplementation of bLF increased the abundance of Lactobacillus and Bifidobacterium and decreased the abundance of Escherichia coli in the cecum on day 7 (P < 0.05). The dietary supplementation of bLF enhanced the growth performance, reduced diarrhea rate in weaning piglets by improving intestinal immunity, morphology and barrier function, balancing intestinal microbiota. And bLF can be a promising feed additive in relieving stress situation of weaning piglets.

Lactoferrin affects in vitro and in vivo fertilization and implantation in rats

Lactoferrin (LF) is present in the oviduct, reduces in vitro gamete interaction, and affects sperm capacitation parameters in humans. Our aim was to investigate LF actions on further stages of the reproductive process in the Wistar rat model. Motile sperm were obtained from cauda epididymis to assess LF binding by direct immunofluorescence and LF effect on acrosome reaction (AR) using a Coomassie blue staining. After ovarian hyperstimulation of female rats, oocytes were surgically recovered and coincubated with motile sperm and different doses of LF to estimate the in vitro fertilization (IVF) rate. To evaluate the LF effect on pregnancy and embryo implantation, female rats (80 days old) were placed with males and received daily intraperitoneal injections of LF during one complete estrous cycle (pregnancy experiments) or during the first 8 gestational days (implantation experiments). The number of pregnant females and live born pups was recorded after labor. Moreover, the number of implantation sites was registered during the implantation period. LF was able to bind to the sperm head, midpiece, and tail. 10 and 100 μg/ml LF stimulated the AR but reduced the IVF rate. The administration of 100 and 200 mg/kg LF significantly decreased the number of implantation sites and the litter size, whereas 100 mg/kg LF declined the pregnancy rate. The results suggest that LF might interfere with the reproductive process, possibly interfering with gamete interaction or inducing a premature AR; nevertheless, the mechanisms involved are yet to be elucidated.

Lactoferrin-Conjugated Nanoparticles as New Antivirals

Lactoferrin is an iron-binding glycoprotein with multiple functions in the body. Its activity against a broad spectrum of both DNA and RNA viruses as well as the ability to modulate immune responses have made it of interest in the pharmaceutical and food industries. The mechanisms of its antiviral activity include direct binding to the viruses or its receptors or the upregulation of antiviral responses by the immune system. Recently, much effort has been devoted to the use of nanotechnology in the development of new antivirals. In this review, we focus on describing the antiviral mechanisms of lactoferrin and the possible use of nanotechnology to construct safe and effective new antiviral drugs.

Inflammatory bowel disease biomarkers

Inflammatory bowel disease (IBD) is characterized as chronic inflammation in the gastrointestinal tract, which includes two main subtypes, Crohn's disease and ulcerative colitis. Endoscopy combined with biopsy is the most effective way to establish IBD diagnosis and disease management. Imaging techniques have also been developed to monitor IBD. Although effective, the methods are expensive and invasive, which leads to pain and discomfort. Alternative noninvasive biomarkers are being explored as tools for IBD prognosis and disease management. This review focuses on novel biomarkers that have emerged in recent years. These serological biomarkers and microRNAs could potentially be used for disease management in IBD, thereby decreasing patient discomfort and morbidity.

Modulation of TDM-induced granuloma pathology by human lactoferrin: a persistent effect in mice

Lactoferrin (LTF), an iron binding protein, is known to exhibit immune modulatory effects on pulmonary pathology during insult-induced models of primary Mycobacterium tuberculosis (Mtb) infection. The effects of LTF correlate with modulation of the immune related development of the pathology, and altering of the histological nature of the physically compact and dense lung granuloma in mice. Specifically, a recombinant human version of LTF limits immediate progression of granulomatous severity following administration of the Mtb cell wall mycolic acid, trehalose 6,6'-dimycolate (TDM), in part through reduced pro-inflammatory responses known to control these events. This current study investigates a limited course of LTF to modulate not only initiation, but also maintenance and resolution of pathology post development of the granulomatous response in mice. Comparison is made to a fusion of LTF with the Fc domain of IgG2 (FcLTF), which is known to extend LTF half-life in circulation. TDM induced granulomas were examined at extended times post insult (day 7 and 14). Both LTF and the novel FcLTF exerted sustained effects on lung granuloma pathology. Reduction of pulmonary pro-inflammatory cytokines TNF-α and IL-1β occurred, correlating with reduced pathology. Increase in IL-6, known to regulate granuloma maintenance, was also seen with the LTFs. The FcLTF demonstrated greater impact than the recombinant LTF, and was superior in limiting damage to pulmonary tissues while limiting residual inflammatory cytokine production.

The dual interaction of antimicrobial peptides on bacteria and cancer cells; mechanism of action and therapeutic strategies of nanostructures

Microbial infection and cancer are two leading causes of global mortality. Discovering and developing new therapeutics with better specificity having minimal side-effects and no drug resistance are of an immense need. In this regard, cationic antimicrobial peptides (AMP) with dual antimicrobial and anticancer activities are the ultimate choice. For better efficacy and improved stability, the AMPs available for treatment still required to be modified. There are several strategies in which AMPs can be enhanced through, for instance, nano-carrier application with high selectivity and specificity enables researchers to estimate the rate of drug delivery to a particular tissue. In this review we present the biology and modes of action of AMPs for both anticancer and antimicrobial activities as well as some modification strategies to improve the efficacy and selectivity of these AMPs.

Lactoferrin as Immune-Enhancement Strategy for SARS-CoV-2 Infection in Alzheimer's Disease Patients

Coronavirus 2 (SARS-CoV2) (COVID-19) causes severe acute respiratory syndrome. Severe illness of COVID-19 largely occurs in older people and recent evidence indicates that demented patients have higher risk for COVID-19. Additionally, COVID-19 further enhances the vulnerability of older adults with cognitive damage. A balance between the immune and inflammatory response is necessary to control the infection. Thus, antimicrobial and anti-inflammatory drugs are hopeful therapeutic agents for the treatment of COVID-19. Accumulating evidence suggests that lactoferrin (Lf) is active against SARS-CoV-2, likely due to its potent antiviral and anti-inflammatory actions that ultimately improves immune system responses. Remarkably, salivary Lf levels are significantly reduced in different Alzheimer's disease (AD) stages, which may reflect AD-related immunological disturbances, leading to reduced defense mechanisms against viral pathogens and an increase of the COVID-19 susceptibility. Overall, there is an urgent necessity to protect AD patients against COVID-19, decreasing the risk of viral infections. In this context, we propose bovine Lf (bLf) as a promising preventive therapeutic tool to minimize COVID-19 risk in patients with dementia or AD.

Lactoferrin of oral fluid is normal and in Alzheimer's disease: laboratory and diagnostic aspects (review of literature)

The article discusses the clinical value of determining the lactoferrin protein in oral fluid - one of the representatives of the saliva proteome. The review is based on the analysis of modern literature, including systematic reviews, the results of multicenter prospective studies, review and original articles by leading experts in this field, presented in the databases PubMed, Scopus, CyberLeninka. The problems of the preanalytical stage, methods for determining lactoferrin are highlighted and information about its content in mixed saliva according to various authors is provided. Special attention is paid to the clinical and diagnostic value of the level of salivary lactoferrin in Alzheimer's disease. According to most authors, the diagnostic sensitivity of this parameter ranges from 87 to 100%. Some mechanisms of the relationship between this protein and the central nervous system (CNS) are shown. In conclusion, it is concluded that salivary lactoferrin can be an "indicator" of the formation of amyloid plaques and can be considered as one of the reliable biomarkers of Alzheimer's disease. This opinion is based both on fundamental ideas about the global relationship between innate immunity and the central nervous system, and on clinical data. The special advantage of this laboratory test is its non-invasiveness, which makes it more preferable in comparison with the determination of amyloid and tau proteins in the cerebrospinal fluid and blood.

Human milk: From complex tailored nutrition to bioactive impact on child cognition and behavior

Human milk is a highly complex liquid food tailor-made to match an infant's needs. Beyond documented positive effects of breastfeeding on infant and maternal health, there is increasing evidence that milk constituents also impact child neurodevelopment. Non-nutrient milk bioactives would contribute to the (long-term) development of child cognition and behavior, a process termed 'Lactocrine Programming'. In this review we discuss the current state of the field on human milk composition and its links with child cognitive and behavioral development. To promote state-of-the-art methodologies and designs that facilitate data pooling and meta-analytic endeavors, we present detailed recommendations and best practices for future studies. Finally, we determine important scientific gaps that need to be filled to advance the field, and discuss innovative directions for future research. Unveiling the mechanisms underlying the links between human milk and child cognition and behavior will deepen our understanding of the broad functions of this complex liquid food, as well as provide necessary information for designing future interventions.

Lactoferrin Induces Erythropoietin Synthesis and Rescues Cognitive Functions in the Offspring of Rats Subjected to Prenatal Hypoxia

The protective effects of recombinant human lactoferrin rhLF (branded “CAPRABEL™”) on the cognitive functions of rat offspring subjected to prenatal hypoxia (7% O₂, 3 h, 14th day of gestation) have been analyzed. About 90% of rhLF in CAPRABEL was iron-free (apo-LF). Rat dams received several injections of 10 mg of CAPRABEL during either gestation (before and after the hypoxic attack) or lactation. Western blotting revealed the appearance of erythropoietin (EPO) alongside the hypoxia-inducible factors (HIFs) in organ homogenates of apo-rhLF-treated pregnant females, their embryos (but not placentas), and in suckling pups from the dams treated with apo-rhLF during lactation. Apo-rhLF injected to rat dams either during pregnancy or nurturing the pups was able to rescue cognitive deficits caused by prenatal hypoxia and improve various types of memory both in young and adult offspring when tested in the radial maze and by the Novel Object Recognition (NOR) test. The data obtained suggested that the apo-form of human LF injected to female rats during gestation or lactation protects the cognitive functions of their offspring impaired by prenatal hypoxia.

Recombinant Human Lactoferrin Reduces Inflammation and Increases Fluoroquinolone Penetration to Primary Granulomas During Mycobacterial Infection of C57Bl/6 Mice

Infection with Mycobacterium tuberculosis (Mtb) results in the primary formation of a densely packed inflammatory foci that limits entry of therapeutic agents into pulmonary sites where organisms reside. No current therapeutic regimens exist that modulate host immune responses to permit increased drug penetration to regions of pathological damage during tuberculosis disease. Lactoferrin is a natural iron-binding protein previously demonstrated to modulate inflammation and granuloma cohesiveness, while maintaining control of pathogenic burden. Studies were designed to examine recombinant human lactoferrin (rHLF) to modulate histological progression of Mtb-induced pathology in a non-necrotic model using C57Bl/6 mice. The rHLF was oral administered at times corresponding to initiation of primary granulomatous response, or during granuloma maintenance. Treatment with rHLF demonstrated significant reduction in size of primary inflammatory foci following Mtb challenge, and permitted penetration of ofloxacin fluoroquinolone therapeutic to sites of pathological disruption where activated (foamy) macrophages reside. Increased drug penetration was accompanied by retention of endothelial cell integrity. Immunohistochemistry revealed altered patterns of M1-like and M2-like phenotypic cell localization post infectious challenge, with increased presence of M2-like markers found evenly distributed throughout regions of pulmonary inflammatory foci in rHLF-treated mice.

Lactoferrin modified by hypohalous acids: Partial loss in activation of human neutrophils

Previously we have shown that lactoferrin (LTF), a protein of secondary neutrophilic granules, can be efficiently modified by hypohalous acids (HOCl and HOBr), which are produced at high concentrations during inflammation and oxidative/halogenative stress by myeloperoxidase, an enzyme of azurophilic neutrophilic granules. Here we compared the effects of recombinant human lactoferrin (rhLTF) and its halogenated derivatives (rhLTF-Cl and rhLTF-Br) on functional responses of neutrophils. Our results demonstrated that after halogenative modification, rhLTF lost its ability to induce mobilization of intracellular calcium, actin cytoskeleton reorganization, and morphological changes in human neutrophils. Moreover, both forms of the halogenated rhLTF prevented binding of N-acetylglucosamine-specific plant lectin Triticum vulgaris agglutinin (WGA) to neutrophils and, in contrast to native rhLTF, inhibited respiratory burst of neutrophils induced by N-formyl-L-methionyl-L-leucyl-L-phenylalanine and by two plant lectins (WGA and PHA-L). However, we observed no differences between the effects of rhLTF, rhLTF-Cl, and rhLTF-Br on respiratory burst of neutrophils induced by phorbol 12-myristate 13-acetate (PMA), digitonin, and number of plant lectins with different glycan-binding specificity. Furthermore, all rhLTF forms interfered with PMA- and ionomycin-induced formation of neutrophil extracellular traps. Thus, halogenative modification of LTF is one of the mechanisms involved in modulating a variety of signaling pathways in neutrophils to control their pro-inflammatory activity.

Lactoferrin for iron-deficiency anemia in children with inflammatory bowel disease: a clinical trial

BACKGROUND

Iron-deficiency anemia (IDA) is common in children with inflammatory bowel disease (IBD); however, oral iron supplements are commonly associated with poor compliance due to gastrointestinal side effects. We compared the effect of lactoferrin versus oral ferrous sulfate for the treatment of IDA in children with IBD.

METHODS

Ninety-two IBD children with IDA were included but only 80 children completed the study and they were randomized into two groups: ferrous sulfate group (n = 40) who received ferrous sulfate 6 mg/kg/day for 3 months and lactoferrin group (n = 40) who received lactoferrin 100 mg/day for 3 months. Complete blood count, serum iron, total iron-binding capacity (TIBC), transferrin saturation (TS), serum ferritin, interleukin-6 (IL-6), and hepcidin 25 were measured before and after the treatment.

RESULTS

Hemoglobin (Hb), mean corpuscular volume, serum iron, TS, and serum ferritin significantly increased, while TIBC decreased significantly after the administration of either ferrous sulfate or lactoferrin compared to their baseline data. In addition, lactoferrin significantly increased Hb, serum iron, TS, and serum ferritin compared to ferrous sulfate. Moreover, lactoferrin significantly decreased IL-6 and hepcidin levels.

CONCLUSION

Lactoferrin is a promising effective treatment with fewer side effects than oral elemental iron in children with IBD and IDA.

CLINICAL TRIAL REGISTRATION

The study was registered at www.pactr.org (PACTR202002763901803).

IMPACT

Iron-deficiency anemia (IDA) in children with inflammatory bowel disease (IBD) is treated with oral iron therapy; however, oral iron supplements are commonly associated with poor compliance due to gastrointestinal side effects. To the best of our knowledge, our study was the first in pediatrics that compared the effect of lactoferrin versus oral ferrous sulfate as an iron supplement for the treatment of IDA in children with IBD. We found that lactoferrin is a promising effective treatment with fewer side effects than oral elemental iron in children with IBD and IDA.

Antimicrobial and Prebiotic Activity of Lactoferrin in the Female Reproductive Tract: A Comprehensive Review

Women’s intimate health depends on several factors, such as age, diet, coexisting metabolic disorders, hormonal equilibrium, sexual activity, drug intake, contraception, surgery, and personal hygiene. These factors may affect the homeostasis of the internal environment of the genital tract: the vulva, vagina and cervix. This equilibrium is dependent on strict and complex mutual interactions between epithelial cells, immunocompetent cells and microorganisms residing in this environment. The microbiota of the genital tract in healthy women is dominated by several species of symbiotic bacteria of the Lactobacillus genus. The bacteria inhibit the growth of pathogenic microorganisms and inflammatory processes by virtue of direct and multidirectional antimicrobial action and, indirectly, by the modulation of immune system activity. For the homeostasis of the genital tract ecosystem, antimicrobial and anti-inflammatory peptides, as well as proteins secreted by mucus cells into the cervicovaginal fluid, have a fundamental significance. Of these, a multifunctional protein known as lactoferrin (LF) is one of the most important since it bridges innate and acquired immunity. Among its numerous properties, particular attention should be paid to prebiotic activity, i.e., exerting a beneficial action on symbiotic microbiota of the gastrointestinal and genital tract. Such activity of LF is associated with the inhibition of bacterial and fungal infections in the genital tract and their consequences, such as endometritis, pelvic inflammation, urinary tract infections, miscarriage, premature delivery, and infection of the fetus and newborns. The aim of this article is to review the results of laboratory as well as clinical trials, confirming the prebiotic action of LF on the microbiota of the lower genital tract.

The Functional Role of Lactoferrin in Intestine Mucosal Immune System and Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), encompassing ulcerative colitis (UC) and Crohn's disease (CD), is one of the main types of intestinal inflammatory diseases with intestine mucosal immune disorder. Intestine mucosal immune system plays a remarkable and important role in the etiology and pathogenesis of IBD. Therefore, understanding the intestine mucosal immune mechanism is a key step to develop therapeutic interventions for IBD. Intestine mucosal immune system and IBD are influenced by various factors, such as inflammation, gut permeability, gut microbiota, and nutrients. Among these factors, emerging evidence show that nutrients play a key role in inflammation activation, integrity of intestinal barrier, and immune cell modulation. Lactoferrin (LF), an iron-binding glycoprotein belonging to transferrin family, is a dietary bioactive component abundantly found in mammalian milk. Notably, LF has been reported to perform diverse biological functions including antibacterial activity, anti-inflammatory activity, intestinal barrier protection, and immune cell modulation, and is involved in maintaining intestine mucosal immune homeostasis. The improved understanding of the properties of LF in intestine mucosal immune system and IBD will facilitate its application in nutrition, clinical medicine, and health. Herein, this review outlines the recent advancements on LF as a potential therapeutic intervention for IBD associated with intestine mucosal immune system dysfunction. We hope this review will provide a reference for future studies and lay a theoretical foundation for LF-based therapeutic interventions for IBD by understanding the particular effects of LF on intestine mucosal immune system.

Disease Tolerance during Viral-Bacterial Co-Infections

Disease tolerance has emerged as an alternative way, in addition to host resistance, to survive viral-bacterial co-infections. Disease tolerance plays an important role not in reducing pathogen burden, but in maintaining tissue integrity and controlling organ damage. A common co-infection is the synergy observed between influenza virus and Streptococcus pneumoniae that results in superinfection and lethality. Several host cytokines and cells have shown promise in promoting tissue protection and damage control while others induce severe immunopathology leading to high levels of morbidity and mortality. The focus of this review is to describe the host cytokines and innate immune cells that mediate disease tolerance and lead to a return to host homeostasis and ultimately, survival during viral-bacterial co-infection.

Lactoferrin: Cytokine Modulation and Application in Clinical Practice

Multiple properties of lactoferrin have been reported in the literature so far. Decades of in vitro and in vivo studies have demonstrated the important antimicrobial, anti-inflammatory, anti-oxidant, and immunomodulating properties. It suggests the use of lactoferrin as an effective and safe option for the treatment of several common disorders. Herein, we show the applications of lactoferrin in clinical practice, highlighting its evidence-based capacities for the treatment of heterogeneous disorders, such as allergic, gastrointestinal, and respiratory diseases, and hematologic, oncologic, gynecologic, dermatologic, and dental disorders. Moreover, the widespread use of lactoferrin in neonatology is summarized here. As a result of its antiviral properties, lactoferrin has also been proposed as a valid option for the treatment for COVID-19 patients. Here, the uses of lactoferrin in clinical practice as a new, safe, and evidence-based treatment for many types of disorders are summarized.

Salivary Lactoferrin Expression in a Mouse Model of Alzheimer's Disease

In the last few years, microbial infection and innate immune theories have been proposed as an alternative approach explaining the etiopathogenesis and origin of Alzheimer's disease (AD). Lactoferrin, one of the main antimicrobial proteins in saliva, is an important modulator of immune response and inflammation, and represents an important defensive element by inducing a broad spectrum of antimicrobial effects against microbial infections. We demonstrated that lactoferrin levels in saliva are decreased in prodromal and dementia stages of AD compared with healthy subjects. That finding seems to be specific to cerebral amyloid-β (Aβ) load as such observation was not observed in healthy elderly controls or those subjects with frontotemporal dementia. In the present study, we analysed salivary lactoferrin levels in a mouse model of AD. We observed robust and early reduction of lactoferrin levels in saliva from 6- and 12-month-old APP/PS1 mice. Because saliva is secreted by salivary glands, we presume that deregulation in salivary glands resulting in reduced salivary lactoferrin levels may occur in AD. To test this hypothesis, we collected submandibular glands from APP/PS1 mice, as well as submandibular gland tissue from AD patients and we analysed the expression levels of key components of the salivary protein signalling pathway. A significant reduction in M3 receptor levels was found along with decreased acetylcholine (Ach) levels in submandibular glands from APP/PS1 mice. Similarly, a reduction in M3 receptor levels was observed in human submandibular glands from AD patients but in that case, the Ach levels were found increased. Our data suggest that the ACh-mediated M3 signalling pathway is impaired in salivary glands in AD, resulting in salivary gland dysfunction and reduced salivary lactoferrin secretion.

Potential Protective Protein Components of Cow's Milk against Certain Tumor Entities

Milk and dairy products, especially from cow's milk, play a major role in the daily human diet. It is therefore hardly surprising that the subject of milk is being extensively researched and that many effects of individual milk components have been characterized as a result. With the wealth of results available today, the influence of milk on the development of various types of cancer and, in particular, its often protective effects have been shown both in vitro and in vivo and in the evaluation of large-scale cohort and case-control studies. Various caseins, diverse whey proteins such as α-lactalbumin (α-LA), bovine α-lactalbumin made lethal to tumor cells (BAMLET), β-lactoglobulin (β-LG), or bovine serum albumin (BSA), and numerous milk fat components, such as conjugated linoleic acid (CLA), milk fat globule membrane (MFGM), or butyrate, as well as calcium and other protein components such as lactoferrin (Lf), lactoferricin (Lfcin), and casomorphines, show antitumor or cytotoxic effects on cells from different tumor entities. With regard to a balanced and health-promoting diet, milk consumption plays a major role in a global context. This work provides an overview of what is known about the antitumoral properties of proteins derived from cow's milk and their modes of action.

Osteogenic effect of polymethyl methacrylate bone cement with surface modification of lactoferrin

Polymethyl methacrylate (PMMA) bone cement is a commonly used filling material in orthopedic surgery. Its good and stable performances make it the most widely used in all kinds of bone cement. With the advancement of the application and research of PMMA bone cement by surgeons, its disadvantages such as non-degradation and non-bioactivity are gradually exposed. In recent years, the biological functions of lactoferrin (LF) have been gradually explored, especially its role in promoting osteogenesis. In this study, LF was modified on the surface of solidified PMMA bone cement (LF/PMMA bone cement) by physical/chemical mixed modification and verified by cytological experiments in vitro. In vitro studies have implicated that PMMA bone cement modified with LF can improve the attachment, expansion, proliferation, extracellular matrix secretion and osteogenic differentiation of mouse preosteoblasts (MC3T3-E1) cells, indicating biocompatibility. This experiment provides a novel insight for improving the biological activity of PMMA bone cement and lays a foundation for broadening the clinical application of PMMA bone cement.

Breast Milk: A Source of Functional Compounds with Potential Application in Nutrition and Therapy

Breast milk is an unbeatable food that covers all the nutritional requirements of an infant in its different stages of growth up to six months after birth. In addition, breastfeeding benefits both maternal and child health. Increasing knowledge has been acquired regarding the composition of breast milk. Epidemiological studies and epigenetics allow us to understand the possible lifelong effects of breastfeeding. In this review we have compiled some of the components with clear functional activity that are present in human milk and the processes through which they promote infant development and maturation as well as modulate immunity. Milk fat globule membrane, proteins, oligosaccharides, growth factors, milk exosomes, or microorganisms are functional components to use in infant formulas, any other food products, nutritional supplements, nutraceuticals, or even for the development of new clinical therapies. The clinical evaluation of these compounds and their commercial exploitation are limited by the difficulty of isolating and producing them on an adequate scale. In this work we focus on the compounds produced using milk components from other species such as bovine, transgenic cattle capable of expressing components of human breast milk or microbial culture engineering.

Inclusion of Oat and Yeast Culture in Sow Gestational and Lactational Diets Alters Immune and Antimicrobial Associated Proteins in Milk

Simple Summary

This study investigated the impact that supplementing sow’s gestation and lactation feed with oat alone or together with brewer’s yeast has on milk proteins and piglet growth and health. Oat and yeast supplements increased abundance of several milk proteins involved in immune protection. Piglets born from either the oat- or yeast-supplemented sows had decreased incidence of diarrhea after weaning. The average birth weights for piglets born of dams that consumed Oat were significantly greater than those that did not. However, piglets born to sows that consumed yeast in combination with oat weighed less at weaning and gained the least amount of weight post-weaning. These data suggest that oat, and to a lesser extent, yeast, added to maternal diets during gestation and lactation can positively impact milk, growth, and health of offspring but given in combination can potentially negatively affect piglet weight gain.

Abstract

Maternal diet supplementation with pro- and prebiotics is associated with decreased incidence of diarrhea and greater piglet performance. This study investigated the impact adding whole ground oat as a prebiotic, alone or in combination with a probiotic, yeast culture (YC) (Saccharomyces cerevisiae), to sow gestation and lactation rations had on milk protein composition, piglet growth, and incidence of post-weaning diarrhea (PWD). Diets: control (CON), CON + yeast culture (YC) [5 g/kg], CON + oat (15% inclusion rate) (Oat) or CON+ YC [5 g/kg] + Oat (15%) were fed the last 30 days of gestation and throughout lactation (18–21 days). Shotgun proteome analysis of day 4 and 7 postpartum milk found 36 differentially abundant proteins (P-adj < 0.1) in both Oat and YC supplemented sows relative to CON. Notable was the increased expression of antimicrobial proteins, lactoferrin and chitinase in milk of Oat and YC sows compared to CON. The levels of IgA, IgM (within colostrum and milk) and IgG (within milk) were similar across treatments. However, colostral IgG levels in Oat-supplemented sows were significantly lower (p < 0.05) than that of the control sows, IgG from Oat-supplemented sows displayed greater reactivity to E. coli-antigens compared with CON and YC. Piglets from sows that consumed Oat alone or in combination weighed significantly more (p < 0.05) at birth compared to CON and YC. However, piglets in the Oat + YC group weighed less at weaning and had the lowest weight gain (p < 0.05) postweaning, compared with CON. Taken together with the observation that piglets of either YC- or Oat-fed sows had less PWD compared to CON and YC+ Oat suggests that Oat or YC supplementation positively impacts piglets through expression of certain milk-associated immune and antimicrobial proteins.

Binding of lactoferrin to the surface of low-density lipoproteins modified by myeloperoxidase prevents intracellular cholesterol accumulation by human blood monocytes

Myeloperoxidase (MPO) is a unique heme-containing peroxidase that can catalyze the formation of hypochlorous acid (HOCl). The strong interaction of MPO with low-density lipoproteins (LDL) promotes proatherogenic modification of LDL by HOCl. The MPO-modified LDL (Mox-LDL) accumulate in macrophages, resulting in the formation of foam cells, which is the pathognomonic symptom of atherosclerosis. A promising approach to prophylaxis and atherosclerosis therapy is searching for remedies that prevent the modification or accumulation of LDL in macrophages. Lactoferrin (LF) has several application points in obesity pathogenesis. We aimed to study LF binding to Mox-LDL and their accumulation in monocytes transformed into macrophages. Using surface plasmon resonance and ELISA techniques, we observed no LF interaction with intact LDL, whereas Mox-LDL strongly interacted with LF. The affinity of Mox-LDL to LF increased with the degree of oxidative modification of LDL. Moreover, an excess of MPO did not prevent interaction of Mox-LDL with LF. LF inhibits accumulation of cholesterol in macrophages exposed to Mox-LDL. The results obtained reinforce the notion of LF potency as a remedy against atherosclerosis.

Cancer Related Anemia: An Integrated Multitarget Approach and Lifestyle Interventions

Cancer is often accompanied by worsening of the patient's iron profile, and the resulting anemia could be a factor that negatively impacts antineoplastic treatment efficacy and patient survival. The first line of therapy is usually based on oral or intravenous iron supplementation; however, many patients remain anemic and do not respond. The key might lie in the pathogenesis of the anemia itself. Cancer-related anemia (CRA) is characterized by a decreased circulating serum iron concentration and transferrin saturation despite ample iron stores, pointing to a more complex problem related to iron homeostatic regulation and additional factors such as chronic inflammatory status. This review explores our current understanding of iron homeostasis in cancer, shedding light on the modulatory role of hepcidin in intestinal iron absorption, iron recycling, mobilization from liver deposits, and inducible regulators by infections and inflammation. The underlying relationship between CRA and systemic low-grade inflammation will be discussed, and an integrated multitarget approach based on nutrition and exercise to improve iron utilization by reducing low-grade inflammation, modulating the immune response, and supporting antioxidant mechanisms will also be proposed. Indeed, a Mediterranean-based diet, nutritional supplements and exercise are suggested as potential individualized strategies and as a complementary approach to conventional CRA therapy.

Nutritional and Behavioral Approaches to Body Composition and Low-Grade Chronic Inflammation Management for Older Adults in the Ordinary and COVID-19 Times

As more insight is gained into personalized health care, the importance of personalized nutritional and behavioral approaches is even more relevant in the COVID-19 era, in addition to the need for further elucidation regarding several diseases/conditions. One of these concerning body composition (in this context; bone, lean and adipose tissue) is osteosarcopenic adiposity (OSA) syndrome. OSA occurs most often with aging, but also in cases of some chronic diseases and is exacerbated with the presence of low-grade chronic inflammation (LGCI). OSA has been associated with poor nutrition, metabolic disorders and diminished functional abilities. This paper addresses various influences on OSA and LGCI, as well as their mutual action on each other, and provides nutritional and behavioral approaches which could be personalized to help with either preventing or managing OSA and LGCI in general, and specifically in the time of the COVID-19 pandemic. Addressed in more detail are nutritional recommendations for and roles of macro- and micronutrients and bioactive food components; the microbiome; and optimal physical activity regimens. Other issues, such as food insecurity and nutritional inadequacy, circadian misalignment and shift workers are addressed as well. Since there is still a lack of longer-term primary studies in COVID-19 patients (either acute or recovered) and interventions for OSA improvement, this discussion is based on the existing knowledge, scientific hypotheses and observations derived from similar conditions or studies just being published at the time of this writing.

Oral Bovine Milk Lactoferrin Administration Suppressed Myopia Development through Matrix Metalloproteinase 2 in a Mouse Model

Recent studies have reported an association between myopia development and local ocular inflammation. Lactoferrin (LF) is an iron-binding protein present in saliva, tears, and mother’s milk. Furthermore, sequestering iron by LF can cause its antibacterial property. Moreover, LF has an anti-inflammatory effect. We aimed to determine the suppressive effect of LF against the development and progress of myopia using a murine lens-induced myopia (LIM) model. We divided male C57BL/6J mice (3 weeks old) into two groups. While the experimental group was orally administered LF (1600 mg/kg/day, from 3-weeks-old to 7-weeks-old), a similar volume of Ringer’s solution was administered to the control group. We subjected the 4-week-old mice to −30 diopter lenses and no lenses on the right and left eyes, respectively. We measured the refraction and the axial length at baseline and 3 weeks after using a refractometer and a spectral domain optical coherence tomography (SD-OCT) system in both eyes. Furthermore, we determined the matrix metalloproteinase-2 (MMP-2) activity, and the amount of interleukin-6 (IL-6), MMP-2, and collagen 1A1 in the choroid or sclera. The eyes with a minus lens showed a refractive error shift and an axial length elongation in the control group, thus indicating the successful induction of myopia. However, there were no significant differences in the aforementioned parameters in the LF group. While LIM increased IL-6 expression and MMP-2 activity, it decreased collagen 1A1 content. However, orally administered LF reversed these effects. Thus, oral administration of LF suppressed lens-induced myopia development by modifying the extracellular matrix remodeling through the IL-6–MMP-2 axis in mice.

Clinical Impact Potential of Supplemental Nutrients as Adjuncts of Therapy in High-Risk COVID-19 for Obese Patients

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) disease (COVID-19) in China at the end of 2019 caused a major global pandemic and continues to be an unresolved global health crisis. The supportive care interventions for reducing the severity of symptoms along with participation in clinical trials of investigational treatments are the mainstay of COVID-19 management because there is no effective standard therapy for COVID-19. The comorbidity of COVID-19 rises in obese patients. Micronutrients may boost the host immunity against viral infections, including COVID-19. In this review, we discuss the clinical impact potential of supplemental nutrients as adjuncts of therapy in high-risk COVID-19 for obese patients.

Lactoferrin concentration and expression in New Zealand cows milked once or twice a day

This study evaluated the concentration and expression of lactoferrin (LF) in cows selected for once a day (OAD) milking compared to twice a day (TAD) milking. Milk samples were collected from the Massey University TAD and OAD herds. Milk traits and expression of LF and insulin-like growth factor 1 (IGF-1) were analyzed with a general linear model that included the fixed effects of milking frequency, lactation number, interaction between milking frequency and lactation number, and as covariates proportion of F, heterosis F × J and deviation from the herd median calving date. Cows milked OAD produced milk with higher (p < .01) concentrations of protein and lactose than TAD milked cows. Compared to TAD cows, cows milked OAD had higher expression of the LF gene (1.40 vs. 1.29 folds, p = .03) and the IGF-1 gene (1.69 vs. 1.48 folds, p = .007). The correlation between the expression of LF gene and the concentration of LF in milk was strong (r = .66 p < .001), but the correlation between the expression of the IGF-1 gene and LF concentration was stronger (r = .94, p < .001). These results suggest that milking frequency affects the milk composition and expression of milk composition genes at early lactation.

Lactoferrin: A Critical Mediator of Both Host Immune Response and Antimicrobial Activity in Response to Streptococcal Infections

Streptococcal species are Gram-positive bacteria responsible for a variety of disease outcomes including pneumonia, meningitis, endocarditis, erysipelas, necrotizing fasciitis, periodontitis, skin and soft tissue infections, chorioamnionitis, premature rupture of membranes, preterm birth, and neonatal sepsis. In response to streptococcal infections, the host innate immune system deploys a repertoire of antimicrobial and immune modulating molecules. One important molecule that is produced in response to streptococcal infections is lactoferrin. Lactoferrin has antimicrobial properties including the ability to bind iron with high affinity and sequester this important nutrient from an invading pathogen. Additionally, lactoferrin has the capacity to alter the host inflammatory response and contribute to disease outcome. This Review presents the most recent published work that studies the interaction between the host innate immune protein lactoferrin and the invading pathogen, Streptococcus.

Lactoferrin, a versatile natural antimicrobial glycoprotein that modulates the host's innate immunity

Lactoferrin is a multifunctional protein found in the secretions of mammals. The antimicrobial activity of lactoferrin was the first to be discovered and was assumed to be solely dependent on its iron-chelating ability. However, lactoferrin has been reported to display proteolytic activity towards bacterial virulence factors and to modulate the host defence by stimulating the immune system and balancing pathogen-induced inflammation. Here, we review the current understandings of the antimicrobial effect, interaction with host cells, and innate immune modulation of lactoferrin, and put forward this moonlighting protein as a possible alternative for antibiotics.

Quantitative proteomic characterization of microvesicles/exosomes from the cerebrospinal fluid of patients with acute bilirubin encephalopathy

Severe hyperbilirubinemia causes neurotoxicity and may lead to acute bilirubin encephalopathy (ABE) during the critical period of central nervous system development. The aim of the present study was to identify differentially expressed proteins (DEPs) in microvesicles/exosomes (MV/E) isolated from the cerebrospinal fluid (CSF) of patients with ABE. Co-precipitation was used to isolate the MV/E from the CSF of patients with ABE and age-matched controls. Isobaric tagging for relative and absolute quantification-based proteomic technology combined with liquid chromatography/tandem mass spectrometry was used to identify DEPs in the MV/E. Bioinformatics analysis was subsequently performed to investigate Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes enriched signaling pathways of these DEPs. A total of four proteins were selected for further validation via western blotting. A total of 291 dysregulated proteins were identified by comparing the patients with ABE with the controls. Bioinformatics analysis indicated the involvement of immune-inflammation-associated cellular processes and signaling pathways in the pathophysiology of ABE. In conclusion, the present study identified the proteomic profile of MV/E isolated from the CSF of patients with ABE. These results may provide an improved understanding of the pathogenesis of ABE and may help to identify early diagnostic biomarkers and therapeutic targets.

Lactoferrin reduces mycobacterial M1-type inflammation induced with trehalose 6,6'-dimycolate and facilitates the entry of fluoroquinolone into granulomas

Primary infection with Mycobacterium tuberculosis (Mtb) results in the formation of a densely packed granulomatous response that essentially limits the entry and efficacy of immune effector cells. Furthermore, the physical nature of the granuloma does not readily permit the entry of therapeutic agents to sites where organisms reside. The Mtb cell wall mycolic acid, trehalose 6,6'-dimycolate (TDM), is a physiologically relevant molecule for modelling macrophage-mediated events during the establishment of the tuberculosis-induced granuloma pathogenesis. At present, there are no treatments for tuberculosis that focus on modulating the host's immune responses. Previous studies showed that lactoferrin (LF), a natural iron-binding protein proven to modulate inflammation, can ameliorate the cohesiveness of granuloma. This led to a series of studies that further examined the effects of recombinant human LF (rHLF) on the histological progression of TDM-induced pathology. Treatment with rHLF demonstrated significant reduction in size and number of inflammatory foci following injections of TDM, together with reduced levels pulmonary pro-inflammatory cytokines TNF-α and IL-1β. LF facilitated greater penetration of fluoroquinolone to the sites of pathology. Mice treated with TDM alone demonstrated exclusion of ofloxacin to regions of inflammatory response, whereas the animals treated with rHLF demonstrated increased penetration to inflammatory foci. Finally, recent findings support the hypothesis that this mycobacterial mycolic acid can specifically recruit M1-like polarized macrophages; rHLF treatment was shown to limit the level of this M1-like phenotypic recruitment, corresponding highly with decreased inflammatory response.

Antibacterial and immunomodulatory effects of Pheromonicin-NM on Escherichia coli-challenged bovine mammary epithelial cells

Mastitis affects cows in all regions of the world and Escherichia coli (E. coli) is by far the most common reason of mastitis. Now antibiotic therapy is still the preferred approach of treating mastitis. However, antibiotic usage is easy to lead to antibiotic resistance. There is an urgent need for developing efficacious alternative antimicrobials. Pheromonicin-NM (PMC-NM) is a new engineered bactericidal peptide consisting of colicin Ia and an anti-porin A antibody mimetic. It can lead to the dissipation of cellular energy and therefore kill the bacteria rapidly. The aim of the present study was to investigate the comparative effects of PMC-NM and antibiotic ceftiofur on antibacterial and innate immune responses of bovine mammary epithelial cells (BMEC) to E. coli infection. We found that E. coli growth was inhibited by PMC-NM from 0.5 h after treatment and was completely inhibited at 3 h, indicating a rapid antibacterial activity for PMC-NM. The mRNA expression of TLR2, IL-1β, IL-8, lactoferrin, LAP, TAP and DEFB1 was increased by PMC-NM treatment at 2 h after E. coli infection, suggesting the enhanced inflammatory responses induced by PMC-NM contribute to pathogens clearance at early phase. By contrast, in E. coli-infected BMECs, ceftiofur treatment upregulated TLR2 and NOD2 levels at 12 h, and extremely elevated transcription levels of TNF-α, IL-1β, IL-8, lactoferrin, LAP, TAP, BNBD5, DEFB1 at 6 h. The excessive expression of these genes at later phase can induce uncontrolled inflammatory responses and finally cause damage. Taken together, PMC-NM might be used as an ideal antibacterial agent against E. coli mastitis.

Viral Hepatitis and Iron Dysregulation: Molecular Pathways and the Role of Lactoferrin

The liver is a frontline immune site specifically designed to check and detect potential pathogens from the bloodstream to maintain a general state of immune hyporesponsiveness. One of the main functions of the liver is the regulation of iron homeostasis. The liver detects changes in systemic iron requirements and can regulate its concentration. Pathological states lead to the dysregulation of iron homeostasis which, in turn, can promote infectious and inflammatory processes. In this context, hepatic viruses deviate hepatocytes' iron metabolism in order to better replicate. Indeed, some viruses are able to alter the expression of iron-related proteins or exploit host receptors to enter inside host cells. Lactoferrin (Lf), a multifunctional iron-binding glycoprotein belonging to the innate immunity, is endowed with potent antiviral activity, mainly related to its ability to block viral entry into host cells by interacting with viral and/or cell surface receptors. Moreover, Lf can act as an iron scavenger by both direct iron-chelation or the modulation of the main iron-related proteins. In this review, the complex interplay between viral hepatitis, iron homeostasis, and inflammation as well as the role of Lf are outlined.

Distribution of Lactoferrin Is Related with Dynamics of Neutrophils in Bacterial Infected Mice Intestine

Lactoferrin (Lf) is a conserved iron-binding glycoprotein with antimicrobial activity, which is present in secretions that recover mucosal sites regarded as portals of invaded pathogens. Although numerous studies have focused on exogenous Lf, little is known about its expression of endogenous Lf upon bacterial infection. In this study, we investigated the distribution of Lf in mice intestine during Escherichia coli (E. coli) K88 infection. PCR and immunohistology staining showed that mRNA levels of Lf significantly increased in duodenum, ileum and colon, but extremely decreased in jejunum at 8 h and 24 h after infection. Meanwhile, endogenous Lf was mostly located in the lamina propria of intestine villi, while Lf receptor (LfR) was in the crypts. It suggested that endogenous Lf-LfR interaction might not be implicated in the antibacterial process. In addition, it was interesting to find that the infiltration of neutrophils into intestine tissues was changed similarly to Lf expression. It indicated that the variations of Lf expression were rather due to an equilibrium between the recruitment of neutrophils and degranulation of activated neutrophils. Thus, this new knowledge will pave the way to a more effective understanding of the role of Lf in intestinal mucosal immunity.

Inhibition of nuclear factor kappa B as a mechanism of Danshensu during Toll-like receptor 2-triggered inflammation in macrophages

Danshensu (DSS) is a water-soluble phenolic compound in Danshen (Salvia Miltiorrhiza Radix et Rhizoma). Although various pharmacological activities have been recognized, little is known regarding its anti-inflammatory effect and related molecular mode of action. In the current study, bone marrow-derived macrophages (BMMs) were activated by a Toll-like receptor 2 (TLR2) agonist Pam3CSK4 with or without DSS intervention. Production of pro-inflammatory cytokines interleukin-6 (IL-6) and interleukin-12 (IL-12) was detected by both enzyme-linked immunosorbent assay (ELISA) and real-time quantitative PCR (RT-qPCR). Activation of signaling pathways involving nuclear factor kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) was assessed by Western blot. Additionally, RNA sequencing (RNA-seq) combined with bioinformatics analyses was applied to investigate the molecular mechanisms of DSS. Emphasis was placed on the construction of the protein-protein interaction (PPI) network and transcription factor (TF) enrichment analysis of data including co-regulated differentially expressed genes (DEGs) in the Pam3CSK4 vs. control and DSS vs. Pam3CSK4 groups. The RT-qPCR and ELISA results showed that DSS effectively inhibited the expressions of IL-6 and IL-12, indicating a significant anti-inflammatory effect. Western blot verified that DSS suppressed the phosphorylation of p65, which was in accordance with the results of the TF enrichment analysis. Additionally, the PPI network analysis showed several key molecules, including lactoferrin (Ltf), CC-chemokine receptor 7 (Ccr7), interferon-gamma (IFN-γ) and C-X-C motif chemokine ligand 9 (Cxcl9), to be regulatory genes that responded to DSS treatment. Overall, our study revealed that DSS has a pronounced anti-inflammatory effect involving TLR2 and macrophages through the NF-κB signaling pathway, which supports the novel application of DSS in the treatment of relevant diseases including atherosclerosis and ischemic or ischemic/perfusion injury of the heart and brain.

Effects of Boswellia Serrata and Whey Protein Powders on Physicochemical Properties of Pork Patties

Processed meat products are prone to oxidative damage and quality decline during storage; however, these problems can be mitigated by the proper formulation of meat productions. This study evaluated the effects of natural anti-oxidants found in Boswellia serrata (B), whey protein powder (W), and their combination on pork patties during storage, exploring changes in textural properties and lipid oxidation susceptibility. The 2% whey-added group exhibited a higher crude protein content than the untreated control group. The highest water-holding capacity and lowest cooking losses were observed in mixed-additive groups (WB₁ (2% W/0.5% B) and WB₂ (2% W/1.0% B), and the highest sensory scores for overall acceptability were obtained for WB₁. Adding B. serrata can neutralize the hardness caused by whey powder, thereby improving palatability. From 7 d (days 7), the extents of lipid oxidation, determined using 2-thiobarbituric acid-reactive substances (TBARS) analysis, for the WB₁ and WB₂ groups were significantly lower than that of the control group. The WB₁ and WB₂ groups exhibited substantially suppressed total bacterial colony and Escherichia coli counts relative to the control group. Our findings suggest that the additive combination of B. serrata and whey protein powders can suppress lipid oxidation, improve storage stability, and enhance textural properties in the production of functional pork patties.