{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T15:06:12Z","timestamp":1785942372233,"version":"3.56.0"},"reference-count":51,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T00:00:00Z","timestamp":1767744000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Recovery and Resilience Facility (RRF), National Recovery Fund","award":["RRF-2.3.1-21-2022-00001"],"award-info":[{"award-number":["RRF-2.3.1-21-2022-00001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The intestinal barrier is essential for gastrointestinal and systemic homeostasis by enabling nutrient absorption while limiting the translocation of pathogens and toxins. When barrier function is impaired, bacterial components such as lipopolysaccharides (LPSs) may cross the epithelium and promote inflammatory signaling. In dogs, chronic inflammatory enteropathies are frequent disorders associated with barrier dysfunction, dysbiosis, and immune dysregulation, and may progress to protein-losing enteropathy or systemic inflammation. Humic substances, particularly humic acid (HA), are natural organic compounds with reported antioxidative, immunomodulatory, and barrier-supporting effects; however, the cellular mechanisms underlying these effects in intestinal and immune models remain insufficiently characterized. This study evaluated the effects of a commercially available HA-based supplement on epithelial barrier integrity and inflammatory responses using an in vitro system combining IPEC-J2 intestinal epithelial cells and primary canine peripheral blood mononuclear cells (PBMCs). Epithelial barrier integrity (FD4 paracellular flux), reactive oxygen species, and cytokine production (TNF-\u03b1, IL-6) were assessed under basal and LPS-stimulated conditions. HA treatment preserved epithelial barrier function and reduced LPS-induced pro-inflammatory cytokine production, supporting further investigation of HA as a nutraceutical adjunct for gut health support in dogs with chronic enteropathies.<\/jats:p>","DOI":"10.3390\/ani16020173","type":"journal-article","created":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T11:46:43Z","timestamp":1767786403000},"page":"173","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Protective Effects of Humic Acid on Intestinal Barrier Dysfunction and Inflammatory Activation in Canine Cell-Based Models"],"prefix":"10.3390","volume":"16","author":[{"given":"Alma Vir\u00e1g","family":"M\u00f3ritz","sequence":"first","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Veterinary Medicine Budapest, 1078 Budapest, Hungary"},{"name":"National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, 1078 Budapest, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Orsolya","family":"Farkas","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Veterinary Medicine Budapest, 1078 Budapest, Hungary"},{"name":"National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, 1078 Budapest, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3380-0827","authenticated-orcid":false,"given":"\u00c1kos","family":"Jerzsele","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Veterinary Medicine Budapest, 1078 Budapest, Hungary"},{"name":"National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, 1078 Budapest, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9955-289X","authenticated-orcid":false,"given":"Nikolett","family":"Palkovicsn\u00e9 P\u00e9zsa","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Veterinary Medicine Budapest, 1078 Budapest, Hungary"},{"name":"National Laboratory of Infectious Animal Diseases, Antimicrobial Resistance, Veterinary Public Health and Food Chain Safety, University of Veterinary Medicine, 1078 Budapest, Hungary"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"bvz039","DOI":"10.1210\/jendso\/bvz039","article-title":"Intestinal Barrier Dysfunction, LPS Translocation, and Disease Development","volume":"4","author":"Ghosh","year":"2020","journal-title":"J. Endocr. Soc."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1016\/S2468-1253(24)00390-X","article-title":"The Intestinal Barrier: A Pivotal Role in Health, Inflammation, and Cancer","volume":"10","author":"Neurath","year":"2025","journal-title":"Lancet Gastroenterol. Hepatol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1093\/ibd\/izae232","article-title":"Intestinal Epithelial Tight Junction Barrier Regulation by Novel Pathways","volume":"31","author":"Arumugam","year":"2025","journal-title":"Inflamm. Bowel Dis."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Barbara, G., Barbaro, M.R., Fuschi, D., Palombo, M., Falangone, F., Cremon, C., Marasco, G., and Stanghellini, V. (2021). Inflammatory and Microbiota-Related Regulation of the Intestinal Epithelial Barrier. Front. Nutr., 8.","DOI":"10.3389\/fnut.2021.718356"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1136\/gutjnl-2018-317726","article-title":"Increased Levels of Systemic LPS-Positive Bacterial Extracellular Vesicles in Patients with Intestinal Barrier Dysfunction","volume":"69","author":"Tulkens","year":"2020","journal-title":"Gut"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"G1060","DOI":"10.1152\/ajpgi.00202.2007","article-title":"Probiotics Ameliorate the Hydrogen Peroxide-Induced Epithelial Barrier Disruption by a PKC- and MAP Kinase-Dependent Mechanism","volume":"294","author":"Seth","year":"2008","journal-title":"Am. J. Physiol. Gastrointest. Liver Physiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"a000034","DOI":"10.1101\/cshperspect.a000034","article-title":"The NF-kappaB Family of Transcription Factors and Its Regulation","volume":"1","author":"Oeckinghaus","year":"2009","journal-title":"Cold Spring Harb. Perspect. Biol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1002\/JLB.MR0318-124R","article-title":"Stressing out the Mitochondria: Mechanistic Insights into NLRP3 Inflammasome Activation","volume":"105","author":"Yabal","year":"2019","journal-title":"J. Leukoc. Biol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"877","DOI":"10.1161\/CIRCRESAHA.117.311401","article-title":"Reactive Oxygen Species in Metabolic and Inflammatory Signaling","volume":"122","author":"Forrester","year":"2018","journal-title":"Circ. Res."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Sahoo, D.K., Heilmann, R.M., Paital, B., Patel, A., Yadav, V.K., Wong, D., and Jergens, A.E. (2023). Oxidative Stress, Hormones, and Effects of Natural Antioxidants on Intestinal Inflammation in Inflammatory Bowel Disease. Front. Endocrinol., 14.","DOI":"10.3389\/fendo.2023.1217165"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1111\/vcp.13068","article-title":"Current Diagnostics for Chronic Enteropathies in Dogs","volume":"50","author":"Allenspach","year":"2022","journal-title":"Vet. Clin. Pathol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Matei, M.-C., Andrei, S.M., Buza, V., Cernea, M.S., Dumitras, D.A., Neagu, D., Rafa, H., Popovici, C.P., Szakacs, A.R., and Catinean, A. (2021). Natural Endotoxemia in Dogs\u2014A Hidden Condition That Can Be Treated with a Potential Probiotic Containing Bacillus Subtilis, Bacillus Licheniformis and Pediococcus Acidilactici: A Study Model. Animals, 11.","DOI":"10.3390\/ani11051367"},{"key":"ref_13","first-page":"68","article-title":"Familial Protein-Losing Enteropathy and Protein-Losing Nephropathy in Soft Coated Wheaten Terriers: 222 Cases (1983\u20131997)","volume":"14","author":"Littman","year":"2000","journal-title":"J. Vet. Intern. Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1043","DOI":"10.1111\/jvim.14739","article-title":"Chronic Diarrhea in Dogs\u2014Retrospective Study in 136 Cases","volume":"31","author":"Volkmann","year":"2017","journal-title":"J. Vet. Intern. Med."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1050","DOI":"10.3748\/wjg.v16.i9.1050","article-title":"Inflammatory Bowel Disease in the Dog: Differences and Similarities with Humans","volume":"16","author":"Cerquetella","year":"2010","journal-title":"World J. Gastroenterol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1002\/ptr.5018","article-title":"Safety and Efficacy of Shilajit (Mumie, Moomiyo)","volume":"28","author":"Stohs","year":"2014","journal-title":"Phytother. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"967","DOI":"10.1016\/j.msec.2015.12.001","article-title":"Humic Acids: Structural Properties and Multiple Functionalities for Novel Technological Developments","volume":"62","author":"Motta","year":"2016","journal-title":"Mater. Sci. Eng. C"},{"key":"ref_18","unstructured":"Tan, K.H. (2014). Humic Matter in Soil and the Environment: Principles and Controversies, CRC Press. [2nd ed.]."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"885","DOI":"10.3748\/wjg.v23.i5.885","article-title":"Impact of Humic Acids on the Colonic Microbiome in Healthy Volunteers","volume":"23","author":"Swidsinski","year":"2017","journal-title":"World J. Gastroenterol."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Huang, J., Xu, P., Shao, M., Wei, B., Zhang, C., and Zhang, J. (2023). Humic Acids Alleviate Dextran Sulfate Sodium-Induced Colitis by Positively Modulating Gut Microbiota. Front. Microbiol., 14.","DOI":"10.3389\/fmicb.2023.1147110"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Li, C., Li, X., Li, P., Wei, B., Zhang, C., Zhu, X., and Zhang, J. (2022). Sodium Humate Alters the Intestinal Microbiome, Short-Chain Fatty Acids, Eggshell Ultrastructure, and Egg Performance of Old Laying Hens. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.986562"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1016\/j.molimm.2023.07.012","article-title":"Sodium Humate Alleviates LPS-Induced Intestinal Barrier Injury by Improving Intestinal Immune Function and Regulating Gut Microbiota","volume":"161","author":"He","year":"2023","journal-title":"Mol. Immunol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1016\/j.phymed.2008.10.003","article-title":"Bimodal Effect of Humic Acids on the LPS-Induced TNF-Alpha Release from Differentiated U937 Cells","volume":"16","author":"Junek","year":"2009","journal-title":"Phytomedicine"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"101948","DOI":"10.1016\/j.mtbio.2025.101948","article-title":"Alchemizing Earth\u2019s Legacy: Bismuth-Engineered Humic Nanoparticles for IBD Theranostics through Mitochondrial Anti-Inflammation and Sustained Intestinal Delivery","volume":"33","author":"Wang","year":"2025","journal-title":"Mater. Today Bio"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Kov\u00e1cs, D., Palkovicsn\u00e9 P\u00e9zsa, N., Jerzsele, \u00c1., S\u00fcth, M., and Farkas, O. (2022). Protective Effects of Grape Seed Oligomeric Proanthocyanidins in IPEC-J2\u2013Escherichia Coli\/Salmonella Typhimurium Co-Culture. Antibiotics, 11.","DOI":"10.3390\/antibiotics11010110"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Pal\u00f3cz, O., P\u00e1szti-Gere, E., G\u00e1lfi, P., and Farkas, O. (2016). Chlorogenic Acid Combined with Lactobacillus Plantarum 2142 Reduced LPS-Induced Intestinal Inflammation and Oxidative Stress in IPEC-J2 Cells. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0166642"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"7474306","DOI":"10.1155\/2016\/7474306","article-title":"Enterococcus Faecium HDRsEf1 Protects the Intestinal Epithelium and Attenuates ETEC-Induced IL-8 Secretion in Enterocytes","volume":"2016","author":"Tian","year":"2016","journal-title":"Mediat. Inflamm."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"716","DOI":"10.1016\/j.jcmgh.2016.09.003","article-title":"Large Animal Models: The Key to Translational Discovery in Digestive Disease Research","volume":"2","author":"Ziegler","year":"2016","journal-title":"Cell Mol. Gastroenterol. Hepatol."},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Verhoeckx, K., Cotter, P., L\u00f3pez-Exp\u00f3sito, I., Kleiveland, C., Lea, T., Mackie, A., Requena, T., Swiatecka, D., and Wichers, H. (2015). Peripheral Blood Mononuclear Cells. The Impact of Food Bioactives on Health: In Vitro and Ex Vivo Models, Springer.","DOI":"10.1007\/978-3-319-16104-4"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"376","DOI":"10.1007\/s11626-011-9405-8","article-title":"Effects of Humic Acids in Vitro","volume":"47","author":"Kron","year":"2011","journal-title":"In Vitro Cell Dev. Biol. Anim."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Chalvon-Demersay, T., Luise, D., Le Floc\u2019h, N., Tesseraud, S., Lambert, W., Bosi, P., Trevisi, P., Beaumont, M., and Corrent, E. (2021). Functional Amino Acids in Pigs and Chickens: Implication for Gut Health. Front. Vet. Sci., 8.","DOI":"10.3389\/fvets.2021.663727"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1007\/s00418-005-0067-z","article-title":"Characterization of a Porcine Intestinal Epithelial Cell Line for in Vitro Studies of Microbial Pathogenesis in Swine","volume":"125","author":"Schierack","year":"2006","journal-title":"Histochem. Cell Biol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1016\/j.vetimm.2012.04.020","article-title":"Expression Dynamics of Toll-like Receptors mRNA and Cytokines in Porcine Peripheral Blood Mononuclear Cells Stimulated by Bacterial Lipopolysaccharide","volume":"147","author":"Uddin","year":"2012","journal-title":"Vet. Immunol. Immunopathol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.jim.2010.03.006","article-title":"Comparative in Vitro Stimulation with Lipopolysaccharide to Study TNFalpha Gene Expression in Fresh Whole Blood, Fresh and Frozen Peripheral Blood Mononuclear Cells","volume":"357","author":"Chen","year":"2010","journal-title":"J. Immunol. Methods"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1482482","DOI":"10.1155\/2020\/1482482","article-title":"Beneficial Effect of a Fermented Wheat Germ Extract in Intestinal Epithelial Cells in Case of Lipopolysaccharide-Evoked Inflammation","volume":"2020","author":"Karancsi","year":"2020","journal-title":"Oxid. Med. Cell. Longev."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1007\/978-1-60761-411-1_4","article-title":"Identification of ROS Using Oxidized DCFDA and Flow-Cytometry","volume":"594","author":"Eruslanov","year":"2010","journal-title":"Methods Mol. Biol."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Luise, D., Bosi, P., Raff, L., Amatucci, L., Virdis, S., and Trevisi, P. (2022). Bacillus Spp. Probiotic Strains as a Potential Tool for Limiting the Use of Antibiotics, and Improving the Growth and Health of Pigs and Chickens. Front. Microbiol., 13.","DOI":"10.3389\/fmicb.2022.801827"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"212","DOI":"10.1039\/C6NJ00960C","article-title":"Supramolecular Combinations of Humic Polyanions as Potent Microbicides with Polymodal Anti-HIV-Activities","volume":"41","author":"Zhernov","year":"2016","journal-title":"New J. Chem."},{"key":"ref_39","first-page":"5420381","article-title":"Alteration in Inflammatory Responses and Cytochrome P450 Expression of Porcine Jejunal Cells by Drinking Water Supplements","volume":"2019","author":"Szita","year":"2019","journal-title":"Mediat. Inflamm."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"16489","DOI":"10.3748\/wjg.v20.i44.16489","article-title":"Microbiota Alterations in Acute and Chronic Gastrointestinal Inflammation of Cats and Dogs","volume":"20","author":"Honneffer","year":"2014","journal-title":"World J. Gastroenterol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1016\/j.ajpath.2012.10.014","article-title":"Lipopolysaccharide Causes an Increase in Intestinal Tight Junction Permeability in Vitro and in Vivo by Inducing Enterocyte Membrane Expression and Localization of TLR-4 and CD14","volume":"182","author":"Guo","year":"2013","journal-title":"Am. J. Pathol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1016\/S1386-1425(99)00249-8","article-title":"Electron Paramagnetic Resonance (EPR) Studies on Stable and Transient Radicals in Humic Acids from Compost, Soil, Peat and Brown Coal","volume":"56A","author":"Jezierski","year":"2000","journal-title":"Spectrochim. Acta A Mol. Biomol. Spectrosc."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1177\/153537020322800412","article-title":"Humic Acid Induces Oxidative DNA Damage, Growth Retardation, and Apoptosis in Human Primary Fibroblasts","volume":"228","author":"Cheng","year":"2003","journal-title":"Exp. Biol. Med."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"674","DOI":"10.1002\/jpln.201200346","article-title":"Soil Humic Acid Aggregation by Dynamic Light Scattering and Laser Doppler Electrophoresis","volume":"176","year":"2013","journal-title":"J. Plant Nutr. Soil. Sci."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"6435","DOI":"10.1021\/es050082x","article-title":"Humic Substances Are Soft and Permeable:\u2009 Evidence from Their Electrophoretic Mobilities","volume":"39","author":"Duval","year":"2005","journal-title":"Environ. Sci. Technol."},{"key":"ref_46","doi-asserted-by":"crossref","unstructured":"Mohammad, S., and Thiemermann, C. (2021). Role of Metabolic Endotoxemia in Systemic Inflammation and Potential Interventions. Front. Immunol., 11.","DOI":"10.3389\/fimmu.2020.594150"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1006\/taap.2000.8954","article-title":"Humic Acid Suppresses the LPS-Induced Expression of Cell-Surface Adhesion Proteins through the Inhibition of NF-kappaB Activation","volume":"166","author":"Gau","year":"2000","journal-title":"Toxicol. Appl. Pharmacol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"791","DOI":"10.1002\/ptr.5319","article-title":"The Antiinflammatory Properties of Humic Substances: A Mini Review","volume":"29","year":"2015","journal-title":"Phytother. Res."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"204","DOI":"10.1007\/s11033-023-09083-z","article-title":"Sodium Humate Ameliorates LPS-Induced Liver Injury in Mice by Inhibiting TLR4\/NF-\u03baB and Activating NRF2\/HO-1 Signaling Pathways","volume":"51","author":"Ma","year":"2024","journal-title":"Mol. Biol. Rep."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"4172","DOI":"10.2527\/jas.2013-7402","article-title":"Effects of Dietary Humic and Butyric Acid on Growth Performance and Response to Lipopolysaccharide in Young Pigs","volume":"92","author":"Weber","year":"2014","journal-title":"J. Anim. Sci."},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Jergens, A.E., and Heilmann, R.M. (2022). Canine Chronic Enteropathy\u2014Current State-of-the-Art and Emerging Concepts. Front. Vet. Sci., 9.","DOI":"10.3389\/fvets.2022.923013"}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/2\/173\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,7]],"date-time":"2026-01-07T11:58:28Z","timestamp":1767787108000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/16\/2\/173"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,7]]},"references-count":51,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2026,1]]}},"alternative-id":["ani16020173"],"URL":"https:\/\/doi.org\/10.3390\/ani16020173","relation":{},"ISSN":["2076-2615"],"issn-type":[{"value":"2076-2615","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,7]]}}}