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1.
Genet Sel Evol ; 56(1): 22, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549172

RESUMO

BACKGROUND: Bovine lactoferrin (Lf) is an iron absorbing whey protein with antibacterial, antiviral, and antifungal activity. Lactoferrin is economically valuable and has an extremely variable concentration in milk, partly driven by environmental influences such as milking frequency, involution, or mastitis. A significant genetic influence has also been previously observed to regulate lactoferrin content in milk. Here, we conducted genetic mapping of lactoferrin protein concentration in conjunction with RNA-seq, ChIP-seq, and ATAC-seq data to pinpoint candidate causative variants that regulate lactoferrin concentrations in milk. RESULTS: We identified a highly-significant lactoferrin protein quantitative trait locus (pQTL), as well as a cis lactotransferrin (LTF) expression QTL (cis-eQTL) mapping to the LTF locus. Using ChIP-seq and ATAC-seq datasets representing lactating mammary tissue samples, we also report a number of regions where the openness of chromatin is under genetic influence. Several of these also show highly significant QTL with genetic signatures similar to those highlighted through pQTL and eQTL analysis. By performing correlation analysis between these QTL, we revealed an ATAC-seq peak in the putative promotor region of LTF, that highlights a set of 115 high-frequency variants that are potentially responsible for these effects. One of the 115 variants (rs110000337), which maps within the ATAC-seq peak, was predicted to alter binding sites of transcription factors known to be involved in lactation-related pathways. CONCLUSIONS: Here, we report a regulatory haplotype of 115 variants with conspicuously large impacts on milk lactoferrin concentration. These findings could enable the selection of animals for high-producing specialist herds.


Assuntos
Lactação , Lactoferrina , Leite , Animais , Feminino , Haplótipos , Lactação/genética , Lactoferrina/genética , Lactoferrina/análise , Lactoferrina/metabolismo , Leite/química , Leite/metabolismo , Bovinos
2.
J Virol ; 98(3): e0157623, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38323814

RESUMO

Adenovirus (AdV) infection of the respiratory epithelium is common but poorly understood. Human AdV species C types, such as HAdV-C5, utilize the Coxsackie-adenovirus receptor (CAR) for attachment and subsequently integrins for entry. CAR and integrins are however located deep within the tight junctions in the mucosa where they would not be easily accessible. Recently, a model for CAR-independent AdV entry was proposed. In this model, human lactoferrin (hLF), an innate immune protein, aids the viral uptake into epithelial cells by mediating interactions between the major capsid protein, hexon, and yet unknown host cellular receptor(s). However, a detailed understanding of the molecular interactions driving this mechanism is lacking. Here, we present a new cryo-EM structure of HAdV-5C hexon at high resolution alongside a hybrid structure of HAdV-5C hexon complexed with human lactoferrin (hLF). These structures reveal the molecular determinants of the interaction between hLF and HAdV-C5 hexon. hLF engages hexon primarily via its N-terminal lactoferricin (Lfcin) region, interacting with hexon's hypervariable region 1 (HVR-1). Mutational analyses pinpoint critical Lfcin contacts and also identify additional regions within hLF that critically contribute to hexon binding. Our study sheds more light on the intricate mechanism by which HAdV-C5 utilizes soluble hLF/Lfcin for cellular entry. These findings hold promise for advancing gene therapy applications and inform vaccine development. IMPORTANCE: Our study delves into the structural aspects of adenovirus (AdV) infections, specifically HAdV-C5 in the respiratory epithelium. It uncovers the molecular details of a novel pathway where human lactoferrin (hLF) interacts with the major capsid protein, hexon, facilitating viral entry, and bypassing traditional receptors such as CAR and integrins. The study's cryo-EM structures reveal how hLF engages hexon, primarily through its N-terminal lactoferricin (Lfcin) region and hexon's hypervariable region 1 (HVR-1). Mutational analyses identify critical Lfcin contacts and other regions within hLF vital for hexon binding. This structural insight sheds light on HAdV-C5's mechanism of utilizing soluble hLF/Lfcin for cellular entry, holding promise for gene therapy and vaccine development advancements in adenovirus research.


Assuntos
Adenovírus Humanos , Proteínas do Capsídeo , Lactoferrina , Receptores Virais , Internalização do Vírus , Humanos , Infecções por Adenovirus Humanos/metabolismo , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/química , Adenovírus Humanos/genética , Adenovírus Humanos/metabolismo , Adenovírus Humanos/ultraestrutura , Sítios de Ligação/genética , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Proteínas do Capsídeo/ultraestrutura , Microscopia Crioeletrônica , Lactoferrina/química , Lactoferrina/genética , Lactoferrina/metabolismo , Lactoferrina/ultraestrutura , Modelos Biológicos , Mutação , Ligação Proteica , Receptores Virais/química , Receptores Virais/genética , Receptores Virais/metabolismo , Receptores Virais/ultraestrutura , Solubilidade , Mucosa Respiratória/citologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia
3.
Nutrients ; 16(3)2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38337738

RESUMO

Athletes often take sport supplements to reduce fatigue and immune disturbances during or after training. This study evaluated the acute effects of concurrent ingestion of alkaline water and L-glutamine on the salivary immunity and hormone responses of boxers after training. Twelve male boxing athletes were recruited in this study. During regular training, the participants were randomly divided into three groups and asked to consume 400 mL of alkaline water (Group A), 0.15 g/kg body weight of L-glutamine with 400 mL of water (Group G), and 0.15 g/kg of L-glutamine with 400 mL of alkaline water (Group A+G) at the same time each day for three consecutive weeks. Before and immediately after the training, saliva, heart rates, and the rate of perceived exertion were investigated. The activity of α-amylase and concentrations of lactoferrin, immunoglobulin A (IgA), testosterone, and cortisol in saliva were measured. The results showed that the ratio of α-amylase activity/total protein (TP) significantly increased after training in Group A+G but not in Group A or G, whereas the ratios of lactoferrin/TP and IgA/TP were unaffected in all three groups. The concentrations of salivary testosterone after training increased significantly in Group A+G but not in Group A or G, whereas the salivary cortisol concentrations were unaltered in all groups. In conclusion, concurrent ingestion of 400 mL of alkaline water and 0.15 g/kg of L-glutamine before training enhanced the salivary α-amylase activity and testosterone concentration of boxers, which would be beneficial for post-exercise recovery.


Assuntos
Boxe , alfa-Amilases Salivares , Humanos , Masculino , Glutamina/metabolismo , Testosterona/metabolismo , Hidrocortisona/metabolismo , Lactoferrina/metabolismo , Imunoglobulina A/metabolismo , Atletas , Ingestão de Alimentos , Saliva/metabolismo
4.
Int J Biol Macromol ; 261(Pt 2): 129842, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309386

RESUMO

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium with adaptive metabolic abilities. It can cause hospital-acquired infections with significant mortality rates, particularly in people with already existing medical conditions. Its ability to develop resistance to common antibiotics makes managing this type of infections very challenging. Furthermore, oxidative stress is a common consequence of bacterial infection and antibiotic therapy, due to formation of reactive oxygen species (ROS) during their mode of action. In this study we aimed to alleviate oxidative stress and enhance the antibacterial efficacy of ciprofloxacin (CPR) antibiotic by its co-encapsulation with naringin (NAR) within a polyelectrolyte complex (PEX). The PEX comprised of polycationic lactoferrin (LF) and polyanionic pectin (PEC). CPR/NAR-loaded PEX exhibited spherical shape with particle size of 237 ± 3.5 nm, negatively charged zeta potential (-23 ± 2.2 mV) and EE% of 61.2 ± 4.9 for CPR and 76.2 ± 3.4 % for NAR. The LF/PEC complex showed prolonged sequential release profile of CPR to limit bacterial expansion, followed by slow liberation of NAR, which mitigates excess ROS produced by CPR's mechanism of action without affecting its efficacy. Interestingly, this PEX demonstrated good hemocompatibility with no significant in vivo toxicity regarding hepatic and renal functions. In addition, infected mice administrated this nanoplatform intravenously exhibited significant CFU reduction in the lungs and kidneys, along with reduced immunoreactivity against myeloperoxidase. Moreover, this PEX was found to reduce the lungs´ oxidative stress via increasing both glutathione (GSH) and catalase (CAT) levels while lowering malondialdehyde (MDA). In conclusion, CPR/NAR-loaded PEX can offer a promising targeted lung delivery strategy while enhancing the therapeutic outcomes of CPR with reduced oxidative stress.


Assuntos
Flavanonas , Lactoferrina , Pectinas , Humanos , Camundongos , Animais , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Pectinas/farmacologia , Pectinas/metabolismo , Antibacterianos/farmacologia , Estresse Oxidativo , Glutationa/metabolismo , Ciprofloxacina/farmacologia , Pulmão/metabolismo
5.
Biophys Chem ; 307: 107193, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38320409

RESUMO

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a moonlighting enzyme. Apart from its primary role in the glycolytic pathway, in many bacterial species it is found in the extracellular milieu and also on the bacterial surface. Positioning on the bacterial surface allows the GAPDH molecule to interact with many host molecules such as plasminogen, fibrinogen, fibronectin, laminin and mucin etc. This facilitates the bacterial colonization of the host. Helicobacter pylori is a major human pathogen that causes a number of gastrointestinal infections and is the main cause of gastric cancer. The binding analysis of H. pylori GAPDH (HpGAPDH) with host molecules has not been carried out. Hence, we studied the interaction of HpGAPDH with holo-transferrin, lactoferrin, haemoglobin, fibrinogen, fibronectin, catalase, plasminogen and mucin using biolayer interferometry. Highest and lowest binding affinity was observed with lactoferrin (4.83 ± 0.70 × 10-9 M) and holo-transferrin (4.27 ± 2.39 × 10-5 M). Previous studies established GAPDH as a heme chaperone involved in intracellular heme trafficking and delivery to downstream target proteins. Therefore, to get insights into heme binding, the interaction between HpGAPDH and hemin was analyzed. Hemin binds to HpGAPDH with an affinity of 2.10 µM while the hemin bound HpGAPDH does not exhibit activity. This suggests that hemin most likely binds at the active site of HpGAPDH, prohibiting substrate binding. Blind docking of hemin with HpGAPDH also supports positioning of hemin at the active site. Metal ions were found to inhibit the activity of HpGAPDH, suggesting that it also possibly occupies the substrate binding site. Furthermore, with metal-bound HpGAPDH, hemin binding was not observed, suggesting metal ions act as an inhibitor of hemin binding. Since GAPDH has been identified as a heme chaperone, it will be interesting to analyse the biological consequences of inhibition of heme binding to GAPDH by metal ions.


Assuntos
Helicobacter pylori , Hemina , Humanos , Hemina/metabolismo , Helicobacter pylori/metabolismo , Fibronectinas/metabolismo , Lactoferrina/metabolismo , Ligação Proteica , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Heme/metabolismo , Fibrinogênio , Plasminogênio/metabolismo , Íons/metabolismo , Mucinas/metabolismo
6.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338734

RESUMO

(1) The aim of the study was to analyze the salivary concentrations of lysozyme, lactoferrin, and sIgA antibodies in adult patients in the late period after allogeneic stem cell transplantation (alloHSCT). The relationship between these concentrations and the salivary secretion rate and the time elapsed after alloHSCT was investigated. The relationship between the concentrations of lysozyme, lactoferrin, and sIgA and the titer of the cariogenic bacteria S. mutans and L. acidophilus was assessed. (2) The study included 54 individuals, aged 19 to 67 (SD = 40.06 ± 11.82; Me = 39.5), who were 3 to 96 months after alloHSCT. The concentrations of lysozyme, lactoferrin, and sIgA were assessed in mixed whole resting saliva (WRS) and mixed whole stimulated saliva (WSS). (3) The majority of patients had very low or low concentrations of the studied salivary components (WRS-lysozyme: 52, lactoferrin: 36, sIgA: 49 patients; WSS-lysozyme: 51, lactoferrin: 25, sIgA: 51 patients). The levels of lactoferrin in both WRS and WSS were statistically significantly higher in the alloHSCT group than in the control group (CG) (alloHSCT patients-WRS: M = 40.18 µg/mL; WSS: M = 27.33 µg/mL; CG-WRS: M = 17.58 µg/mL; WSS: 10.69 µg/mL). No statistically significant correlations were observed between lysozyme, lactoferrin, and sIgA concentrations and the time after alloHSCT. In the group of patients after alloHSCT a negative correlation was found between the resting salivary flow rate and the concentration of lactoferrin and sIgA. The stimulated salivary flow rate correlated negatively with lactoferrin and sIgA concentrations. Additionally, the number of S. mutans colonies correlated positively with the concentration of lysozyme and sIgA. (4) The concentrations of non-specific and specific immunological factors in the saliva of patients after alloHSCT may differ when compared to healthy adults; however, the abovementioned differences did not change with the time after transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Muramidase , Adulto , Humanos , Muramidase/metabolismo , Lactoferrina/metabolismo , Saliva/metabolismo , Imunoglobulina A Secretora/metabolismo , Proteínas e Peptídeos Salivares
7.
Mol Autism ; 15(1): 4, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233886

RESUMO

BACKGROUND: Gastrointestinal symptoms and inflammatory gastrointestinal diseases exist at higher rates in the autistic population. It is not clear however whether autism is associated with elevated gastrointestinal inflammation as studies examining non-invasive faecal biomarkers report conflicting findings. To understand the research landscape and identify gaps, we performed a systematic review and meta-analysis of studies measuring non-invasive markers of gastrointestinal inflammation in autistic and non-autistic samples. Our examination focused on faecal biomarkers as sampling is non-invasive and these markers are a direct reflection of inflammatory processes in the gastrointestinal tract. METHODS: We extracted data from case-control studies examining faecal markers of gastrointestinal inflammation. We searched PubMed, Embase, Cochrane CENTRAL, CINAHL, PsycINFO, Web of Science Core Collection and Epistemonikos and forward and backwards citations of included studies published up to April 14, 2023 (PROSPERO CRD42022369279). RESULTS: There were few studies examining faecal markers of gastrointestinal inflammation in the autistic population, and many established markers have not been studied. Meta-analyses of studies examining calprotectin (n = 9) and lactoferrin (n = 3) were carried out. A total of 508 autistic children and adolescents and 397 non-autistic children and adolescents were included in the meta-analysis of calprotectin studies which found no significant group differences (ROM: 1.30 [0.91, 1.86]). Estimated differences in calprotectin were lower in studies with siblings and studies which did not exclude non-autistic controls with gastrointestinal symptoms. A total of 139 autistic participants and 75 non-autistic controls were included in the meta-analysis of lactoferrin studies which found no significant group differences (ROM: 1.27 [0.79, 2.04]). LIMITATIONS: All studies included in this systematic review and meta-analysis examined children and adolescents. Many studies included non-autistic controls with gastrointestinal symptoms which limit the validity of their findings. The majority of studies of gastrointestinal inflammation focused on children under 12 with few studies including adolescent participants. Most studies that included participants aged four or under did not account for the impact of age on calprotectin levels. Future studies should screen for relevant confounders, include larger samples and explore gastrointestinal inflammation in autistic adolescents and adults. CONCLUSIONS: There is no evidence to suggest higher levels of gastrointestinal inflammation as measured by calprotectin and lactoferrin are present in autistic children and adolescents at the population level. Preliminary evidence suggests however that higher calprotectin levels may be present in a subset of autistic participants, who may be clinically characterised by more severe gastrointestinal symptoms and higher levels of autistic traits.


Assuntos
Transtorno Autístico , Adolescente , Criança , Humanos , Biomarcadores/análise , Trato Gastrointestinal/química , Trato Gastrointestinal/metabolismo , Inflamação , Lactoferrina/análise , Lactoferrina/metabolismo , Complexo Antígeno L1 Leucocitário/análise
8.
Compr Rev Food Sci Food Saf ; 23(1): e13288, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38284584

RESUMO

Whey protein derived bioactives, including α-lactalbumin, ß-lactoglobulin, bovine serum albumin, lactoferrin, transferrin, and proteose-peptones, have exhibited wide ranges of functional, biological and therapeutic properties varying from anticancer, antihypertensive, and antimicrobial effects. In addition, their functional properties involve gelling, emulsifying, and foaming abilities. For these reasons, this review article is framed to understand the relationship existed in between those compound levels and structures with their main functional, biological, and therapeutic properties exhibited either in vitro or in vivo. The impacts of hydrolysis mechanism and separation techniques in enhancing those properties are likewise discussed. Furthermore, special emphasize is given to multifunctional effects of whey derived bioactives and their future trends in ameliorating further food, pharmaceutical, and nutraceutical products. The underlying mechanism effects of those properties are still remained unclear in terms of activity levels, efficacy, and targeted effectiveness. For these reasons, some important models linking to functional properties, thermal properties and cell circumstances are established. Moreover, the coexistence of radical trapping groups, chelating groups, sulfhydryl groups, inhibitory groups, and peptide bonds seemed to be the key elements in triggering those functions and properties. Practical Application: Whey proteins are the byproducts of cheese processing and usually the exploitation of these food waste products has increasingly getting acceptance in many countries, especially European countries. Whey proteins share comparable nutritive values to milk products, particularly on their richness on important proteins that can serve immune protection, structural, and energetic roles. The nutritive profile of whey proteins shows diverse type of bioactive molecules like α-lactalbumin, ß-lactoglobulin, lactoferrin, transferrin, immunoglobulin, and proteose peptones with wide biological importance to the living system, such as in maintaining immunological, neuronal, and signaling roles. The diversification of proteins of whey products prompted scientists to exploit the real mechanisms behind of their biological and therapeutic effects, especially in declining the risk of cancer, tumor, and further complications like diabetes type 2 and hypertension risk effects. For these reasons, profiling these types of proteins using different proteomic and peptidomic approaches helps in determining their biological and therapeutic targets along with their release into gastrointestinal tract conditions and their bioavailabilities into portal circulation, tissue, and organs. The wide applicability of those protein fractions and their derivative bioactive products showed significant impacts in the field of emulsion and double emulsion stabilization by playing roles as emulsifying, surfactant, stabilizing, and foaming agents. Their amphoteric properties helped them to act as excellent encapsulating agents, particularly as vehicle for delivering important vitamins and bioactive compounds. The presence of ferric elements increased their transportation to several metal-ions in the same time increased their scavenging effects to metal-transition and peroxidation of lipids. Their richness with almost essential and nonessential amino acids makes them as selective microbial starters, in addition their richness in sulfhydryl amino acids allowed them to act a cross-linker in conjugating further biomolecules. For instance, conjugating gold-nanoparticles and fluorescent materials in targeting diseases like cancer and tumors in vivo is considered the cutting-edges strategies for these versatile molecules due to their active diffusion across-cell membrane and the presence of specific transporters to these therapeutic molecules.


Assuntos
Neoplasias , Peptidomiméticos , Eliminação de Resíduos , Humanos , Proteínas do Soro do Leite/metabolismo , Lactalbumina/metabolismo , Proteínas do Leite/química , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia , Lactoferrina/metabolismo , Peptonas/metabolismo , Hidrólise , Emulsões , Proteômica , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Aminoácidos
9.
Biochem Biophys Res Commun ; 695: 149480, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38215552

RESUMO

Here, we report that human lactoferrin (hLF), known for its anticancer properties, induced intracellular activation of the Na+/H+ exchanger (NHE) 7 in human lung cancer PC-9 cells. Compared to non-fused hLF, the fusion of human serum albumin (HSA) with hLF (hLF-HSA) facilitated its internalization into PC-9 cells in a caveolae-mediated manner, thereby exhibiting enhanced anti-proliferative effects. Although hLF alone did not exhibit any discernible effects, hLF-HSA resulted in organelle alkalization as detected using an acidotropic pH indicator. hLF-HSA-induced elevation of organelle pH and inhibition of cancer growth were abolished by NHE7 siRNA. hLF-HSA upregulated NHE7. Thus, upon cellular uptake, hLF-HSA triggers proton leakage through the upregulation of NHE7. This process led to organelle alkalization, probably in the trans-Golgi network (TGN) as suggested by the localization of NHE7 in PC-9 cells, thereby suppressing lung cancer cell growth. Forcing the cellular uptake of hLF alone using a caveolae-mediated endocytosis activator led to an increase in organelle pH. Furthermore, cell entry of hLF also activated proton-loading NHE7, leading to organelle acidification in the pancreatic cancer cell line MIA PaCa-2. Therefore, the intracellularly delivered hLF functions as an activator of NHE7.


Assuntos
Lactoferrina , Neoplasias Pulmonares , Trocadores de Sódio-Hidrogênio , Humanos , Lactoferrina/metabolismo , Lactoferrina/farmacologia , Neoplasias Pulmonares/metabolismo , Prótons , Trocadores de Sódio-Hidrogênio/metabolismo , Rede trans-Golgi/metabolismo
10.
Stroke ; 55(1): 166-176, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38063014

RESUMO

BACKGROUND: Within hours after intracerebral hemorrhage (ICH) onset, masses of polymorphonuclear neutrophils (PMNs) infiltrate the ICH-affected brain. After degranulation involving controlled release of many toxic antimicrobial molecules, the PMNs undergo rapid apoptosis and then are removed by phagocytic microglia/macrophages (MΦ) through a process called efferocytosis. Effective removal of PMNs may limit secondary brain damage and inflammation; however, the molecular mechanisms governing these cleanup activities are not well understood. We propose that scavenger receptor CD91 on myeloid phagocytes especially in presence of CD91 ligand, LTF (lactoferrin, protein abundant in PMNs), plays an important role in clearance of dead apoptotic PMNs (ANs). METHODS: Mice/rats were subjected to an autologous blood injection model of ICH. Primary cultured microglia were used to assess phagocytosis of ANs. Immunohistochemistry was employed to assess CD91 expression and PMN infiltration. CD91 knockout mice selectively in myeloid phagocytes (Mac-CD91-KO) were used to establish the CD91/LTF function in phagocytosis and in reducing ICH-induced injury, as assessed using behavioral tests, hematoma resolution, and oxidative stress. RESULTS: Masses of PMNs are found in ICH-affected brain, and they contain LTF. MΦ at the outer border of hematoma are densely packed, expressing CD91 and phagocytosing ANs. Microglia deficient in CD91 demonstrate defective phagocytosis of ANs, and mice deficient in CD91 (Mac-CD91-KO) subjected to ICH injury have increased neurological dysfunction that is associated with impaired hematoma resolution (hemoglobin and iron clearance) and elevated oxidative stress. LTF that normally ameliorates ICH injury in CD91-proficient control mice shows reduced therapeutic effects in Mac-CD91-KO mice. CONCLUSIONS: Our study suggests that CD91 plays a beneficial role in improving ANs phagocytosis and ultimately post-ICH outcome and that the beneficial effect of LTF in ICH is in part dependent on presence of CD91 on MΦ.


Assuntos
Lesões Encefálicas , Neutrófilos , Ratos , Camundongos , Animais , Neutrófilos/metabolismo , Lactoferrina/metabolismo , Encéfalo/metabolismo , Hemorragia Cerebral/tratamento farmacológico , Macrófagos/metabolismo , Microglia/metabolismo , Hematoma/tratamento farmacológico
11.
Eur J Clin Microbiol Infect Dis ; 43(2): 313-324, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38072880

RESUMO

PURPOSE: We investigated the role of fecal calprotectin (FC) and lactoferrin (FL) as predictive biomarkers in Clostridioides difficile infection (CDI). METHODS: We assembled a prospective cohort including all patients with a laboratory-confirmed CDI diagnosis between January and December 2017. FL and FC levels were measured at diagnosis by commercial ELISA and EIA kits. We investigated the diagnostic accuracy of FC and FL to predict CDI recurrence and severity (study outcomes) and explored optimal cut-off values in addition to those proposed by the manufacturers (200 µg/g and 7.2 µg/mL, respectively). RESULTS: We included 170 CDI cases (152 first episodes and 18 recurrences). The rates of recurrence (first episodes only) and severity (entire cohort) were 9.2% (14/152) and 46.5% (79/170). Both FL and FC levels were significantly higher in patients who developed study outcomes. Optimal cut-off values for FC and FL to predict CDI recurrence were 1052 µg/g and 6.0 µg/mL. The optimal cut-off value for FC yielded higher specificity (60.9%) and positive predictive value (PPV) (16.9%) than that proposed by the manufacturer. Regarding CDI severity, the optimal cut-off value for FC (439 µg/g) also provided higher specificity (43.9%) and PPV (54.1%) than that of the manufacturer, whereas the optimal cut-off value for FL (4.6 µg/mL) resulted in an improvement of PPV (57.5%). CONCLUSION: By modifying the thresholds for assay positivity, the measurement of FC and FL at diagnosis is useful to predict recurrence and severity in CDI. Adding these biomarkers to current clinical scores may help to individualize CDI management.


Assuntos
Infecções por Clostridium , Lactoferrina , Humanos , Lactoferrina/metabolismo , Complexo Antígeno L1 Leucocitário/análise , Estudos Prospectivos , Fezes/química , Biomarcadores/análise , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia
12.
Free Radic Biol Med ; 212: 309-321, 2024 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-38159893

RESUMO

Vascular endothelial dysfunction (ED) is one of the mechanisms underlying obesity-related hypertension. Perivascular adipose tissue (PVAT) surrounds blood vessels and influences the vascular endothelium function. Previous studies have demonstrated the antihypertensive effects of lactoferrin (LF) and its hydrolysates through various mechanisms. However, the effect of LF on ED and PVAT has not yet been investigated. In this study, we examined the influence of LF on ED and PVAT using high-fat diet mice as well as MAEC cells and 3T3-L1 adipocytes. Finally, LF supplementation decreases the systolic blood pressure (SBP), serum adhesion molecule (ICAM-1 and VCAM-1), and aorta ROS levels, and improves endothelium-dependent relaxation function in high-fat diet mice. Moreover, LF supplementation down-regulates the Tak1/IL-18/eNOS pathway between PVAT and aorta and enhances the NO generation in high-fat diet mice. In addition, we observe that LF decreases the expression levels of IL-18 and p-Tak1 in 3T3-L1 adipocytes, but fails to influence the eNOS and p-eNOS expression levels in MAEC cells. Finally, the significant associations between LF and IL-18 and SBP and hypertension risk are also observed in obesity children only. These findings provide evidence that the Tak1/IL-18/eNOS pathway between the aorta and PVAT is important in obesity-related ED, and LF may improve ED or even hypertension by down-regulating this pathway.


Assuntos
Endotélio Vascular , Hipertensão , Criança , Humanos , Camundongos , Animais , Endotélio Vascular/metabolismo , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Interleucina-18/farmacologia , Transdução de Sinais , Obesidade/tratamento farmacológico , Obesidade/genética , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Dieta Hiperlipídica/efeitos adversos , Hipertensão/tratamento farmacológico , Hipertensão/genética , Hipertensão/metabolismo
13.
Int J Biol Macromol ; 258(Pt 1): 128838, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128798

RESUMO

Pseudomonas aeruginosa is one of the leading causes of opportunistic infections such as chronic wound infection that could lead to multiple organ failure and death. Gallium (Ga3+) ions are known to inhibit P. aeruginosa growth and biofilm formation but require carrier for localized controlled delivery. Lactoferrin (LTf), a two-lobed protein, can deliver Ga3+ at sites of infection. This study aimed to develop a Ga-LTf complex for the treatment of wound infection. The characterisation of the Ga-LTf complex was conducted using differential scanning calorimetry (DSC), Infra-Red (FTIR) and Inductive Coupled Plasma Optical Emission Spectrometry (ICP-OES). The antibacterial activity was assessed by agar disc diffusion, liquid broth and biofilm inhibition assays using the colony forming units (CFUs). The healing capacity and biocompatibility were evaluated using a P.aeruginosa infected wound in a rat model. DSC analyses showed thermal transition consistent with apo-lactoferrin; FTIR confirmed the complexation of gallium to lactoferrin. ICP-OES confirmed the controlled local delivery of Ga3+. Ga-LTf showed a 0.57 log10 CFUs reduction at 24 h compared with untreated control in planktonic liquid broth assay. Ga-LTf showed the highest antibiofilm activity with a 2.24 log10 CFUs reduction at 24 h. Furthermore, Ga-LTf complex is biocompatible without any adverse effect on brain, kidney, liver and spleen of rats tested in this study. Ga-LTf can be potentially promising novel therapeutic agent to treat pathogenic bacterial infections.


Assuntos
Gálio , Ratos , Animais , Gálio/química , Gálio/metabolismo , Gálio/farmacologia , Pseudomonas aeruginosa , Lactoferrina/metabolismo , Antibacterianos/farmacologia , Biofilmes
14.
J Reprod Immunol ; 161: 104182, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38159430

RESUMO

Iron overload is linked to heightened susceptibility to ferroptosis, a process increasingly implicated in diabetes pathogenesis. This present study aims to assess the utility of Lactoferrin in predicting different stages of GDM and explore its association with disease pathology and ferroptosis. In this observational study, 72 pregnant women were recruited and categorized into three groups: healthy pregnant women without diabetes (NGDM, n = 24), early gestational diabetes (eGDM, n = 24), and established gestational diabetes (GDM, n = 24), all receiving standard antenatal care at 12 weeks of gestation. Circulating levels of ferritin, soluble transferrin receptor (sTFR), and Lactoferrin using multiplexed bead-based cytokine immunoassay. Gene expression analysis focused on analyzing crucial ferroptosis regulators, SLC7A11 and GPX4, in isolated peripheral blood mononuclear cells (PBMCs). A significant elevation in ferritin levels and a decrease in the sTFR: Ferritin ratio supported iron overload and disrupted iron homeostasis in GDM subjects. Notably, Lactoferrin levels were significantly lower in women with GDM than in the control group and those with eGDM. This decline in Lactoferrin correlated with increased hyperglycemia indicators and reduced expression of ferroptosis regulators among GDM patients. Furthermore ROC curve analysis demonstrated that Lactoferrin shows promise as a valuable marker for distinguishing individuals with GDM from those with eGDM. Lactoferrin shows promise as a biomarker for detecting GDM. These findings indicate its role as a potential biomarker and highlight Lactoferrin as a critical regulator of hyperglycemia and ferroptosis in women with GDM.


Assuntos
Diabetes Gestacional , Ferroptose , Hiperglicemia , Sobrecarga de Ferro , Gravidez , Feminino , Humanos , Diabetes Gestacional/diagnóstico , Ferro/metabolismo , Lactoferrina/metabolismo , Leucócitos Mononucleares/metabolismo , Ferritinas , Receptores da Transferrina/metabolismo , Biomarcadores
15.
Int J Biol Macromol ; 257(Pt 2): 128710, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101660

RESUMO

α-Amylase activity differs between individuals and is influenced by dietary behavior and salivary constituents, but limited information is available on the relationship between α-amylase activity and saliva components. This study investigated the impact of salivary proteins on α-amylase activity, their various correlations, the effect of mucin (MUC5B and MUC7) and lactoferrin on the enzymatic kinetics of α-amylase, and the mechanisms of these interactions using the quartz crystal microbalance with dissipation (QCM-D) technique and molecular docking. The results showed that α-amylase activity was significantly correlated with the concentrations of MUC5B (R2 = 0.42, p < 0.05), MUC7 (R2 = 0.35, p < 0.05), and lactoferrin (R2 = 0.35, p < 0.05). An in vitro study demonstrated that α-amylase activity could be significantly increased by mucins and lactoferrin by decreasing the Michaelis constant (Km) of α-amylase. Moreover, the results from the QCM-D and molecule docking suggested that mucin and lactoferrin could interact with α-amylase to form stable α-amylase-mucin and α-amylase-lactoferrin complexes through hydrophobic interactions, electrostatic interactions, Van der Waals forces, and hydrogen bonds. In conclusion, these findings indicated that the salivary α-amylase activity depended not only on the α-amylase content, but also could be enhanced by the interactions of mucin/lactoferrin with α-amylase.


Assuntos
Mucinas , Saliva , Humanos , Mucinas/química , Saliva/química , Lactoferrina/metabolismo , Simulação de Acoplamento Molecular , Técnicas de Microbalança de Cristal de Quartzo , alfa-Amilases/metabolismo
16.
Int J Mol Sci ; 24(23)2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38069040

RESUMO

Our previous study showed that not only bovine lactoferrin (LF), the protein of milk and neutrophils, but also the human species forms complexes with oleic acid (OA) that inhibit tumor growth. Repeated injections of human LF in complex with OA (LF/8OA) to hepatoma-carrying mice decelerated tumor growth and increased animals' longevity. However, whether the effect of the LF/8OA complex is directed exclusively against malignant cells was not studied. Hence, its effect on normal blood cells was assayed, along with its possible modulation of ceruloplasmin (CP), the preferred partner of LF among plasma proteins. The complex LF/8OA (6 µM) caused hemolysis, unlike LF alone or BSA/8OA (250 µM). The activation of neutrophils with exocytosis of myeloperoxidase (MPO), a potent oxidant, was induced by 1 µM LF/8OA, whereas BSA/8OA had a similar effect at a concentration increased by an order. The egress of heme-containing proteins, i.e., MPO and hemoglobin, from blood cells affected by LF/8OA was followed by a pronounced oxidative/halogenating stress. CP, which is the natural inhibitor of MPO, added at a concentration of 2 mol per 1 mol of LF/8OA abrogated its cytotoxic effect. It seems likely that CP can be used effectively in regulating the LF/8OA complex's antitumor activity.


Assuntos
Carcinoma Hepatocelular , Hemeproteínas , Camundongos , Humanos , Animais , Ceruloplasmina/metabolismo , Ácido Oleico/farmacologia , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Hemeproteínas/metabolismo , Heme/metabolismo
17.
Int J Mol Sci ; 24(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069169

RESUMO

Our previous animal studies found that the preventive effects of lactoferrin (Lf) on alcoholic liver injury (ALI) are associated with nuclear factor E2-related factor 2 (Nrf2). To further explore the causality, experiments were performed using rat normal liver BRL-3A cells. Lf treatment reduced ethanol-induced death and apoptosis; meanwhile, Lf treatment alleviated excessive LDH release. These findings confirmed the protection of Lf against ethanol-induced injury in BRL-3A cells. Mechanistically, Lf treatment reversed the reduction in nuclear Nrf2 induced by ethanol without affecting the cytoplasmic Nrf2 level, which led to antioxidant enzyme activity restoration. However, the blocking of Nrf2 nuclear translocation by ML385 eliminated the protective effects of Lf. In a conclusion, Lf protects BRL-3A cells from ethanol-induced injury via promoting Nrf2 nuclear translocation.


Assuntos
Etanol , Lactoferrina , Ratos , Animais , Etanol/toxicidade , Etanol/metabolismo , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Linhagem Celular , Fígado/metabolismo , Antioxidantes/farmacologia , Estresse Oxidativo
18.
Sci Rep ; 13(1): 22434, 2023 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-38104179

RESUMO

The aim of this study was to investigate factors affecting total, true protein and lactoferrin (Lf) concentrations in human milk (HM) and to evaluate the changes in protein concentrations over the course of lactation (first to sixth month postpartum). HM samples were collected from exclusively breastfeeding mothers during six time periods (1-6 months postpartum); 198 breast milk samples were collected in total. The concentrations of total and true protein in HM were determined using the MIRIS human milk analyzer (HMA). The assessment of HM protein content was also performed in skim HM samples and quantified by bicinchoninic methods with the Bicinchoninic Acid Protein Assay Kit. In turn, Lf content in skim HM samples was determined by the enzyme-linked immunosorbent assay (ELISA) in accordance with a slightly modified procedure. In the first month of lactation total protein concentration was negatively correlated with maternal pre-pregnancy BMI (r = - 0.397; p = 0.022), whereas in the third month postpartum, positive correlation with maternal age was found (r = 0.399; p = 0.021). Considering Lf concentration, in the first month of lactation, it was positively correlated with baby's birth weight (r = 0.514; p = 0.002). In the next months (from second to sixth) no relationships between Lf concentration and maternal and infants' factors were observed. The concentration of protein and Lf in HM changes dynamically throughout lactation. Maternal and infant characteristics may impact the HM protein and Lf content, especially in the first month postpartum.


Assuntos
Lactoferrina , Leite Humano , Lactente , Gravidez , Feminino , Humanos , Leite Humano/química , Lactoferrina/metabolismo , Lactação/metabolismo , Aleitamento Materno , Período Pós-Parto , Proteínas do Leite/metabolismo
19.
Biomolecules ; 13(12)2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38136635

RESUMO

The increasing interest in innovative solutions for addressing bone defects has driven research into the use of Bioactive Mesoporous Glasses (MBGs). These materials, distinguished by their well-ordered mesoporous structure, possess the capability to accommodate plant extracts with well-established osteogenic properties, including bovine lactoferrin (bLF), as part of their 3D scaffold composition. This harmonizes seamlessly with the ongoing advancements in the field of biomedicine. In this study, we fabricated 3D scaffolds utilizing MBGs loaded with extracts from parsley leaves (PL) and embryogenic cultures (EC), rich in bioactive compounds such as apigenin and kaempferol, which hold potential benefits for bone metabolism. Gelatin Methacryloyl (GelMa) served as the polymer, and bLF was included in the formulation. Cytocompatibility, Runx2 gene expression, ALP enzyme activity, and biomineralization were assessed in preosteoblastic MC3T3-E1 cell cultures. MBGs effectively integrated PL and EC extracts with loadings between 22.6 ± 0.1 and 43.6 ± 0.3 µM for PL and 26.3 ± 0.3 and 46.8 ± 0.4 µM for EC, ensuring cell viability through a release percentage between 28.3% and 59.9%. The incorporation of bLF in the 3D scaffold formulation showed significant differences compared to the control in all assays, even at concentrations below 0.2 µM. Combinations, especially PL + bLF at 0.19 µM, demonstrated additive potential, with superior biomineralization compared to EC. In summary, this study highlights the effectiveness of MBGs in incorporating PL and EC extracts, along with bLF, into 3D scaffolds. The results underscore cytocompatibility, osteogenic activity, and biomineralization, offering exciting potential for future in vivo applications.


Assuntos
Lactoferrina , Petroselinum , Lactoferrina/farmacologia , Lactoferrina/metabolismo , Osteoblastos/metabolismo , Técnicas de Cultura de Células
20.
BMC Biol ; 21(1): 242, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907907

RESUMO

BACKGROUND: Lactoferrin is an active protein in breast milk that plays an important role in the growth and development of infants and is implicated as a neuroprotective agent. The incidence of depression is currently increasing, and it is unclear whether the lack of lactoferrin during lactation affects the incidence of depressive-like behavior in adulthood. RESULTS: Lack of lactoferrin feeding during lactation affected the barrier and innate immune functions of the intestine, disrupted the intestinal microflora, and led to neuroimmune dysfunction and neurodevelopmental delay in the hippocampus. When exposed to external stimulation, adult lactoferrin feeding-deficient mice presented with worse depression-like symptoms; the mechanisms involved were activation of the LPS-TLR4 signalling pathway in the intestine and hippocampus, reduced BDNF-CREB signaling pathway in hippocampus, increased abundance of depression-related bacteria, and decreased abundance of beneficial bacteria. CONCLUSIONS: Overall, our findings reveal that lactoferrin feeding deficient during lactation can increase the risk of depressive-like behavior in adults. The mechanism is related to the regulatory effect of lactoferrin on the development of the "microbial-intestinal-brain" axis.


Assuntos
Lactação , Lactoferrina , Animais , Feminino , Camundongos , Intestinos , Lactação/metabolismo , Lactoferrina/metabolismo , Leite , Transdução de Sinais
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