Humic acids alleviate dextran sulfate sodium-induced colitis by positively modulating gut microbiota

Abstract

Humic acids (HAs) are natural polymers with diverse functional groups that have been documented and utilized in traditional Chinese medicine. Dextran sulfate sodium (DSS)-induced colitis has been used as a model to study inflammatory bowel disease. In this research, we investigate the effect of HAs on ameliorating DSS-induced colitis in mice. Our aim here was to investigate if HAs could be a remedy against colitis and the mechanisms involved. The results show that HAs facilitated a regain of body weight and restoration of intestinal morphology after DSS-induced colitis. HAs treatment alters the community of gut microbiota with more Lactobacillus and Bifidobacterium. Changes in bacterial community result in lower amounts of lipopolysaccharides in mouse sera, as well as lower levels of inflammatory cytokines through the Toll-like receptor 4 (TLR4)-NF-κB pathway. HAs also promoted the expression of tight junction proteins, which protect the intestinal barrier from DSS damage. Cell experiments show that HAs display an inhibitory effect on DSS growth as well. These results suggest that HAs can alleviate colitis by regulating intestinal microbiota, reducing inflammation, maintaining mucosal barriers, and inhibiting pathogen growth. Thus, HAs offer great potential for the prevention and treatment of colitis.

Assessment of the Impact of Humic Acids on Intestinal Microbiota, Gut Integrity, Ileum Morphometry, and Cellular Immunity of Turkey Poults Fed an Aflatoxin B1-Contaminated Diet

“…Recent studies have shown that HA can significantly increase the size and absorption area of the villi in jejunum and ileum of rats fed an AFB 1 -contaminated diet [22], which clearly agrees with the results of the present study. Several mechanisms might be responsible for the observed increase in ileum villi size and absorption area in HA-fed poults.…”

“…(C) Anti-inflammatory and immune-modulatory properties [ 21 ]—HA can suppress the inflammatory response triggered by AFB 1 and stimulate the immune system, generating a more favorable environment for Firmicutes to flourish. (D) Improvement of gut barrier function—HA can improve gut barrier integrity by enhancing the production of intestinal epithelial cells and tight junctions [ 22 ]. Results showing increased gut viscosity and gene expression of mucin 2 (MUC-2) in the cecum of chickens consuming HA [ 23 ] also suggest greater mucin production in poultry.…”

The Modulatory Influence of Humic Acid on Cognitive Impairment and Neurobehavioral Changes Induced by Colitis in Adult Male Wistar Rats

“…In a recent study by Huang et al [43], it was reported that humic acid alleviated DSS-induced colitis as it helped to restore intestinal morphology, alter the community of gut microbiota, reduce the levels of in ammatory cytokines by its modulatory role on the NF-κB-TLR4 pathway, and additionally enhanced the expression of tight junction proteins, which guard against DSS damage to the gut barrier. Modulation of hippocampal oxidative stress marker as well as hippocampal pro-in ammatory mediators by rice bran extract was reported [54].…”

Efficacy of water application of a humic substance, butyric acid, vitamins C, D, and E and/or electrolytes on performance and mortality in health-challenged nursery pigs¹

“…Modulating the gut microbiota with humic substances is associated with an alleviation of dextran sulfate sodium-induced colitis by increasing the abundance of Lactobacillus and Bifidobacterium in mice ( Huang et al, 2023 ). In broiler chickens, feeding humic substances resulted in the stability of goblet cells in the jejunum villi from abrupt changes in diets, thus helping to strengthen the mucosal cells in the epithelium of the intestine ( López-García et al, 2023 ).…”