Lactoferrin Ameliorates Ovalbumin-Induced Asthma in Mice through Reducing Dendritic-Cell-Derived Th2 Cell Responses

SLAMF7 is a key molecule that promotes M1 polarization in lung tissue macrophages of high-fat diet-fed asthma mice model

OBJECTIVE

Investigating the regulatory role of Signaling lymphocyte activation molecule family 7 (SLAMF7) in the pathogenesis of asthma in a high fat-fed (HFD) mouse model, providing targets for treating obese asthma.

METHODS

We constructed a mouse model of obese asthma, and Quantitative real-time RT-PCR (qPCR) for the detection of mRNA levels of SLAMF7 and M1 polarization markers of macrophages. Lung tissue levels of SLAMF7 protein, macrophage M1 polarization markers, and neutrophil markers were measured by Western blotting. The proportions of SLAMF7+ macrophages and neutrophils in bronchoalveolar lavage fluid (BALF) were determined by flow cytometry. Neutrophil inflammatory cytokine levels were determined by Enzyme-linked immunosorbent assay (ELISA). Immunofluorescence performed the colocalization of SLAMF7 and inducible nitric oxide synthase (iNOS). The regulation of SLAMF7 on M1 polarization of macrophages was verified by cell experiments.

RESULTS

The group of HFD asthmatic mice had more severe airway inflammation and mucus secretion. They also had higher SLAMF7 levels, airway neutrophil inflammation and M1 polarization of macrophages in lung tissue. SLAMF7 overexpression increased M1 polarization, and SLAMF7 knockdown decreased M1 polarization. The expression change of SLAMF7 affects the expression of NR4A1 and RUNX3, inhibiting NR4A1 and promoting RUNX3.

CONCLUSION

SLAMF7 expression is increased in obese asthma mice, accompanied by neutrophil infiltration and enhanced M1 polarization. SLAMF7 promotes M1 polarization may be through the NR4A1-RUNX3 axis, suppressing NR4A1, and promoting RUNX3.

Air Pollution-Associated Rhinitis: Exploring the Preventive Role of Nutritional Supplements Against Particulate Matter-Induced Inflammation

Air pollution, particularly particulate matter (PM), poses a significant health risk worldwide, with rhinitis emerging as a prevalent respiratory condition. This review explores the association between air pollution and rhinitis, focusing on PM-induced inflammation and the potential preventive role of nutritional supplements. A comprehensive literature search was conducted using the PubMed and Scopus databases, covering studies from inception to 2024 that investigated air pollution, rhinitis, and nutritional interventions. This review synthesizes evidence linking PM exposure to increased prevalence and exacerbation of rhinitis through various inflammatory mechanisms. We further examine the potential of nutritional supplements, including kefir peptides, lactoferrin, vitamin D, polyunsaturated fatty acids, and probiotics, in mitigating PM-induced inflammation and rhinitis symptoms. However, the evidence regarding the role of these supplements in modulating immune responses and reducing inflammation related to PM-induced rhinitis is limited. This review highlights the potential efficacy of nutritional interventions in preventing and managing air pollution-associated rhinitis, offering a complementary approach to environmental regulations in addressing this public health challenge.

Chemical characterization of Siraitia grosvenorii granules and their efficacy and mechanism of action on PM2.5-induced acute lung injury

This study aimed to investigate the potential protective properties of a traditional Chinese medicine (TCM) herbal product, Siraitia grosvenorii granules (SGG) against PM2.5-induced lung injury, as well as their active constituents and underlying mechanisms. The chemical composition of SGG, such as wogonin (MOL000173), luteolin (MOL000006), nobiletin (MOL005828), naringenin (MOL004328), acacetin (MOL001689), were identified via ultra-high-performance liquid chromatography-Q Exactive (UHPLC-QE) Orbitrap/MS. The specific targets and pathways through which the compounds exert their effects on acute lung injury were then predicted via network pharmacology. The lung-protective effects of SGG against particulate matter (PM2.5) were investigated via in vivo experiments. Results showed that PM2.5-induced lung damage was associated with oxidative stress, suppression of PI3K/AKT/Nrf2 pathway, and increased levels of certain alarmins & cytokines in blood and bronchial alveolar lavage fluid (BALF). However, SGG reversed these changes, particularly tissue damage and oxidative stress, suggesting that lung protection is mediated by the antioxidant effect, which mitigates the release of alarmin and inflammation.

Machine learning analysis of CD4+ T cell gene expression in diverse diseases: insights from cancer, metabolic, respiratory, and digestive disorders

CD4+ T cells play a pivotal role in the immune system, particularly in adaptive immunity, by orchestrating and enhancing immune responses. CD4+ T cell-related immune responses exhibit diverse characteristics in different diseases. This study utilizes gene expression analysis of CD4+ T cells to classify and understand complex diseases. We analyzed the dataset consisting of samples from various diseases, including cancers, metabolic disorders, circulatory and respiratory diseases, and digestive ailments, as well as 53 healthy controls. Each sample contained expression data for 22,881 genes. Four feature ranking algorithms, incremental feature selection method, synthetic minority oversampling technique, and four classification algorithms were utilized to pinpoint essential genes, extract classification rules and build efficient classifiers. The following analysis focused on genes across rules, such as AK4, CALU, LINC01271, and RUSC1-AS1. AK4 and CALU show fluctuating levels in diseases like asthma, Crohn's disease, and breast cancer. The analysis results and existing research suggest that they may play a role in these diseases. LINC01271 generally has higher expression in conditions including asthma, Crohn's disease, and diabetes. RUSC1-AS1 is more expressed in chronic diseases like asthma and Crohn's, but less in acute illnesses like tonsillitis and influenza. This highlights the distinct roles of these genes in different diseases. Our approach highlights the potential for developing novel therapeutic strategies based on the transcriptional profiles of CD4+ T cells.

Signature Proteins in Small Extracellular Vesicles of Granulocytes and CD4+ T-Cell Subpopulations Identified by Comparative Proteomic Analysis

Several studies have described the proteomic profile of different immune cell types, but only a few have also analysed the content of their delivered small extracellular vesicles (sEVs). The aim of the present study was to compare the protein signature of sEVs delivered from granulocytes (i.e., neutrophils and eosinophils) and CD4+ T cells (i.e., TH1, TH2, and TH17) to identify potential biomarkers of the inflammatory profile in chronic inflammatory diseases. Qualitative (DDA) and quantitative (DIA-SWATH) analyses of in vitro-produced sEVs revealed proteome variations depending on the cell source. The main differences were found between granulocyte- and TH cell-derived sEVs, with a higher abundance of antimicrobial proteins (e.g., LCN2, LTF, MPO) in granulocyte-derived sEVs and an enrichment of ribosomal proteins (RPL and RPS proteins) in TH-derived sEVs. Additionally, we found differentially abundant proteins between neutrophil and eosinophil sEVs (e.g., ILF2, LTF, LCN2) and between sEVs from different TH subsets (e.g., ISG15, ITGA4, ITGB2, or NAMPT). A "proof-of-concept" assay was also performed, with TH2 biomarkers ITGA4 and ITGB2 displaying a differential abundance in sEVs from T2high and T2low asthma patients. Thus, our findings highlight the potential use of these sEVs as a source of biomarkers for diseases where the different immune cell subsets studied participate, particularly chronic inflammatory pathologies such as asthma or chronic obstructive pulmonary disease (COPD).

Lung antimicrobial proteins and peptides: from host defense to therapeutic strategies

Representing severe morbidity and mortality globally, respiratory infections associated with chronic respiratory diseases, including complicated pneumonia, asthma, interstitial lung disease, and chronic obstructive pulmonary disease, are a major public health concern. Lung health and the prevention of pulmonary disease rely on the mechanisms of airway surface fluid secretion, mucociliary clearance, and adequate immune response to eradicate inhaled pathogens and particulate matter from the environment. The antimicrobial proteins and peptides contribute to maintaining an antimicrobial milieu in human lungs to eliminate pathogens and prevent them from causing pulmonary diseases. The predominant antimicrobial molecules of the lung environment include human α- and β-defensins and cathelicidins, among numerous other host defense molecules with antimicrobial and antibiofilm activity such as PLUNC (palate, lung, and nasal epithelium clone) family proteins, elafin, collectins, lactoferrin, lysozymes, mucins, secretory leukocyte proteinase inhibitor, surfactant proteins SP-A and SP-D, and RNases. It has been demonstrated that changes in antimicrobial molecule expression levels are associated with regulating inflammation, potentiating exacerbations, pathological changes, and modifications in chronic lung disease severity. Antimicrobial molecules also display roles in both anticancer and tumorigenic effects. Lung antimicrobial proteins and peptides are promising alternative therapeutics for treating and preventing multidrug-resistant bacterial infections and anticancer therapies.

Investigation of lactotransferrin messenger RNA expression levels as an anti-type 2 asthma biomarker

BACKGROUND

Lactotransferrin (LTF) has an immunomodulatory function, and its expression levels are associated with asthma susceptibility.

OBJECTIVES

We sought to investigate LTF messenger RNA (mRNA) expression levels in human bronchial epithelial cells (BECs) as an anti-type 2 (T2) asthma biomarker.

METHODS

Association analyses between LTF mRNA expression levels in BECs and asthma-related phenotypes were performed in the Severe Asthma Research Program (SARP) cross-sectional (n = 155) and longitudinal (n = 156) cohorts using a generalized linear model. Correlation analyses of mRNA expression levels between LTF and all other genes were performed by Spearman correlation.

RESULTS

Low LTF mRNA expression levels were associated with asthma susceptibility and severity (P < .025), retrospective and prospective asthma exacerbations, and low lung function (P < 8.3 × 10-3). Low LTF mRNA expression levels were associated with high airway T2 inflammation biomarkers (sputum eosinophils and fractional exhaled nitric oxide; P < 8.3 × 10-3) but were not associated with blood eosinophils or total serum IgE. LTF mRNA expression levels were negatively correlated with expression levels of TH2 or asthma-associated genes (POSTN, NOS2, and MUC5AC) and eosinophil-related genes (IL1RL1, CCL26, and IKZF2) and positively correlated with expression levels of TH1 and inflammation genes (IL12A, MUC5B, and CC16) and TH17-driven cytokines or chemokines for neutrophils (CXCL1, CXCL6, and CSF3) (P < 3.5 × 10-6).

CONCLUSIONS

Low LTF mRNA expression levels in BECs are associated with asthma susceptibility, severity, and exacerbations through upregulation of airway T2 inflammation. LTF is a potential anti-T2 biomarker, and its expression levels may help determine the balance of eosinophilic and neutrophilic asthma.

AdipoRon, an adiponectin receptor agonist, modulates AMPK signaling pathway and alleviates ovalbumin-induced airway inflammation in a murine model of asthma

Asthma is a long-term disease that causes airways swelling and inflammation and in turn airway narrowing. AdipoRonis an orally active synthetic small molecule that acts as a selective agonist at theadiponectin receptor 1 and 2. The aim of the current study is to delineate the protective effect and the potential underlying mechanism ofadipoRon inairway inflammationinduced byovalbumin (OVA) in comparison withdexamethasone. Adult maleSwiss Albino micewere sensitized to OVA on days 0 and 7, then challenged with OVA on days 14, 15 and 16. AdipoRon was administered orally for 6 days starting from the 11th day till the 16th and 1 h prior to OVA in the challenge days. Obtained results from asthmatic control group showed a significant decrease in serum adiponectin concentration, an increase in inflammatory cell counts inthe bronchoalveolar lavage fluid(BALF), CD68 protein expression, inflammatory cytokine concentration and oxidative stress as well. Administration of adipoRon enhanced antioxidant mechanisms limiting oxidative stress by significantly increasing reduced glutathione (GSH) pulmonary content, decreasing serum lactate dehydrogenase (LDH) together with malondialdehyde (MDA) significant reduction in lung tissue. In addition, it modulated the levels of serum immunoglobulin E (IgE), pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-4, IL-13, nuclear factor kappa B (NF-κB) and the anti-inflammatory one IL-10 improving lung inflammation as revealed by histopathological evaluation. Furthermore, lung tissue expression of nuclear factor erythroid 2-related factor (Nrf2) and 5'AMP-activated protein kinase (AMPK) were significantly increased adipoRon. Notably, results of adipoRon received group were comparable to those of dexamethasone group. In conclusion, our study demonstrates that adipoRon can positively modulate adiponectin expression with activation of AMPK pathway and subsequent improvement in inflammatory and oxidative signaling.

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.

Lactoferrin as a therapeutic agent for attenuating hepatic stellate cell activation in thioacetamide-induced liver fibrosis

Liver fibrosis is a chronic liver disease caused by prolonged liver injuries. Excessive accumulation of extracellular matrix replaces the damaged hepatocytes, leading to fibrous scar formation and fibrosis induction. Lactoferrin (LF) is a glycoprotein with a conserved, monomeric signal polypeptide chain, exhibiting diverse physiological functions, including antioxidant, anti-inflammatory, antibacterial, antifungal, antiviral, and antitumoral activities. Previous study has shown LF's protective role against chemically-induced liver fibrosis in rats. However, the mechanisms of LF in liver fibrosis are still unclear. In this study, we investigated LF's mechanisms in thioacetamide (TAA)-induced liver fibrosis in rats and TGF-β1-treated HSC-T6 cells. Using ultrasonic imaging, H&E, Masson's, and Sirius Red staining, we demonstrated LF's ability to improve liver tissue damage and fibrosis induced by TAA. LF reduced the levels of ALT, AST, and hydroxyproline in TAA-treated liver tissues, while increasing catalase levels. Additionally, LF treatment decreased mRNA expression of inflammatory factors such as Il-1β and Icam-1, as well as fibrogenic factors including α-Sma, Collagen I, and Ctgf in TAA-treated liver tissues. Furthermore, LF reduced TAA-induced ROS production and cell death in FL83B cells, and decreased α-SMA, Collagen I, and p-Smad2/3 productions in TGF-β1-treated HSC-T6 cells. Our study highlights LF's ability to ameliorate TAA-induced hepatocyte damage, oxidative stress, and liver fibrosis in rats, potentially through its inhibitory effect on HSC activation. These findings suggest LF's potential as a therapeutic agent for protecting against liver injuries and fibrosis.

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.

Time to Kill and Time to Heal: The Multifaceted Role of Lactoferrin and Lactoferricin in Host Defense

Lactoferrin is an iron-binding glycoprotein present in most human exocrine fluids, particularly breast milk. Lactoferrin is also released from neutrophil granules, and its concentration increases rapidly at the site of inflammation. Immune cells of both the innate and the adaptive immune system express receptors for lactoferrin to modulate their functions in response to it. On the basis of these interactions, lactoferrin plays many roles in host defense, ranging from augmenting or calming inflammatory pathways to direct killing of pathogens. Complex biological activities of lactoferrin are determined by its ability to sequester iron and by its highly basic N-terminus, via which lactoferrin binds to a plethora of negatively charged surfaces of microorganisms and viruses, as well as to mammalian cells, both normal and cancerous. Proteolytic cleavage of lactoferrin in the digestive tract generates smaller peptides, such as N-terminally derived lactoferricin. Lactoferricin shares some of the properties of lactoferrin, but also exhibits unique characteristics and functions. In this review, we discuss the structure, functions, and potential therapeutic uses of lactoferrin, lactoferricin, and other lactoferrin-derived bioactive peptides in treating various infections and inflammatory conditions. Furthermore, we summarize clinical trials examining the effect of lactoferrin supplementation in disease treatment, with a special focus on its potential use in treating COVID-19.

Potential of Lactoferrin in the Treatment of Lung Diseases

Lactoferrin (LF) is a multifunctional iron-binding glycoprotein that exhibits a variety of properties, such as immunomodulatory, anti-inflammatory, antimicrobial, and anticancer, that can be used to treat numerous diseases. Lung diseases continue to be the leading cause of death and disability worldwide. Many of the therapies currently used to treat these diseases have limited efficacy or are associated with side effects. Therefore, there is a constant pursuit for new drugs and therapies, and LF is frequently considered a therapeutic agent and/or adjunct to drug-based therapies for the treatment of lung diseases. This article focuses on a review of the existing and most up-to-date literature on the contribution of the beneficial effects of LF on the treatment of lung diseases, including asthma, viral infections, cystic fibrosis, or lung cancer, among others. Although in vitro and in vivo studies indicate significant potency of LF in the treatment of the listed diseases, only in the case of respiratory tract infections do human studies seem to confirm them by demonstrating the effectiveness of LF in reducing episodes of illness and shortening the recovery period. For lung cancer, COVID-19 and sepsis, the reports are conflicting, and for other diseases, there is a paucity of human studies conclusively confirming the beneficial effects of LF.