Cho, Kwang Keun;Lee, Seung Ho;Choi, In Soon;Lee, Sang Won
Journal of Life Science
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v.31
no.6
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pp.595-602
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2021
Human intestinal microbiota play an important role in the regulation of the host's metabolism. There is a close pathological and physiological interaction between dysbiosis of the intestinal microflora and obesity and metabolic syndrome. Akkermansia muciniphila, which was recently isolated from human feces, accounts for about 1-4% of the intestinal microbiota population. The use of A. muciniphila- derived external membrane protein Amuc_1100 and extracellular vesicles (EVs) could be a new strategy for the treatment of obesity. A. muciniphila is considered a next-generation probiotic (NGP) for the treatment of metabolic disorders, such as obesity. Faecalibacterium prausnitzii accounts for about 5% of the intestinal microbiota population in healthy adults and is an indicator of gut health. F. prausnitzii is a butyrate-producing bacterium, with anti-inflammatory effects, and is considered an NGP for the treatment of immune diseases and diabetes. Postbiotics are complex mixtures of metabolites contained in the cell supernatant secreted by probiotics. Parabiotics are microbial cells in which probiotics are inactivated. Paraprobiotics and postbiotics have many advantages over probiotics, such as clear chemical structures, safe dose parameters, and a long shelf life. Thus, they have the potential to replace probiotics. The most natural strategy to restore the imbalance of the intestinal ecosystem normally is to use NGPs among commensal bacteria in the gut. Therefore, it is necessary to develop new foods or drugs such as parabiotics and postbiotics using NGPs.
Objective: The aim of this study was to characterize the fecal microbiota of broiler chickens reared in the presence of different shades of light-emitting diode (LED) lights, correlating this information with biochemical and molecular evidence that allowed drawing conclusions on the state of health of the animals. Methods: Overall, the metagenomic approach on fecal samples was associated with evaluations on enzymes involved in the cellular response to oxidative stress: glutathione peroxidase (GPX), superoxide dismutase and catalase; while the inflammatory aspect was studied through the dosage of a proinflammatory cytokine, the interleukin 6 (IL-6), and the evaluation of the matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9). Specifically, analysis was performed on distinct groups of chickens respectively raised in the presence of neutral (K = 3,300 to 3,700), cool (K = 5,500 to 6,000), and warm (K = 3,000 to 2,500) LED lightings, and a direct comparison was performed with animals reared with traditional neon lights. Results: The metagenomic analysis highlighted the presence of two most abundant bacterial phyla, the Firmicutes and the Bacteroidetes, with the latter characterized by a greater relative abundance (p<0.05) in the group of animals reared with Neutral LED light. The analysis on the enzymes involved in the antioxidant response showed an effect of the LED light, regardless of the applied shade, of reducing the expression of GPX (p<0.01), although this parameter is not correlated to an effective reduction in the tissue amount of the enzyme. Regarding the inflammatory state, no differences associated with IL-6 and MMP-9 were found; however, is noteworthy the significant reduction of MMP-2 activity in tissue samples obtained from animals subjected to illumination with neutral LED light. Conclusion: This evidence, combined with the metagenomic findings, supports a potential positive effect of neutral LED lighting on animal welfare, although these considerations must be reflected in more targeted biochemical evaluations.
Qian Fan;Yini Xu;Yingping Xiao;Caimei Yang;Wentao Lyu;Hua Yang
Animal Bioscience
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v.37
no.7
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pp.1213-1224
/
2024
Objective: Enterotypes (ETs) are the clustering of gut microbial community structures, which could serve as indicators of growth performance and carcass traits. However, ETs have been sparsely investigated in waterfowl. The objective of this study was to identify the ileal ETs and explore the correlation of the ETs with growth performance and carcass traits in Muscovy ducks. Methods: A total of 200 Muscovy ducks were randomly selected from a population of 5,000 ducks at 70-day old, weighed and slaughtered. The growth performance and carcass traits, including body weight, dressed weight and evidenced weight, dressed percentage, percentage of apparent yield, breast muscle weight, leg muscle weight, percentage of leg muscle and percentage of breast muscle, were determined. The contents of ileum were collected for the isolation of DNA and 16S rRNA gene sequencing. The ETs were identified based on the 16S rRNA gene sequencing data and the correlation of the ETs with growth performance and carcass traits was performed by Spearman correlation analysis. Results: Three ETs (ET1, ET2, and ET3) were observed in the ileal microbiota of Muscovy ducks with significant differences in number of features and α-diversity among these ETs (p<0.05). Streptococcus, Candida Arthritis, and Bacteroidetes were the presentative genus in ET1 to ET3, respectively. Correlation analysis revealed that Lactococcus and Bradyrhizobium were significantly correlated with percentage of eviscerated yield and leg muscle weight (p<0.05) while ETs were found to have a close association with percentage of eviscerated yield, leg muscle weight, and percentage of leg muscle in Muscovy ducks. However, the growth performance of ducks with different ETs did not show significant difference (p>0.05). Lactococcus were found to be significantly correlated with leg muscle weight, dressed weight, and percentage of eviscerated yield. Conclusion: Our findings revealed a substantial variation in carcass traits associated with ETs in Muscovy ducks. It is implied that ETs might have the potential to serve as a valuable biomarker for assessing duck carcass traits. It would provide novel insights into the interaction of gut microbiota with growth performance and carcass traits of ducks.
Colorectal cancer (CRC) is the third most common cancer in the world. Although 5-fluorouracil (5-FU) is the representative chemotherapy drug for colorectal cancer, it has therapeutic limits due to its chemoresistant characteristics. Colorectal cancer cells can develop into cancer stem cells (CSCs) with self-renewal potential, thereby causing malignant tumors. The human gastrointestinal tract contains a complex gut microbiota that is essential for the host's homeostasis. Recently, many studies have reported correlations between gut flora and the onset, progression, and treatment of CRC. The present study confirms that the most representative symbiotic bacteria in humans, Lactobacillus plantarum (LP) supernatant (SN), selectively inhibit the characteristics of 5-FU-resistant colorectal cancer cells (HT-29 and HCT-116). LP SN inhibited the expression of the specific markers CD44, 133, 166, and ALDH1 of CSCs. The combination therapy of LP SN and 5-FU inhibited the survival of CRCs and led to cell death by inducing caspase-3 activity. The combination therapy of LP SN and 5-FU induced an anticancer mechanism by inactivating the Wnt/β-catenin signaling of chemoresistant CRC cells, and reducing the formation and size of colonospheres. In conclusion, our results show that LP SN can enhance the therapeutic effect of 5-FU for colon cancer, and reduce colorectal cancer stem-like cells by reversing the development of resistance to anticancer drugs. This implies that probiotic substances may be useful therapeutic alternatives as biotherapeutics for chemoresistant CRC.
Ye Seul Son;Mijin Kwon;Naeun Son;Sang-Kyu Kim;Mi-Young Son
Journal of Microbiology and Biotechnology
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v.33
no.10
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pp.1309-1316
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2023
To exert their beneficial effects, it is essential for the commensal bacteria of probiotic supplements to be sufficiently protected as they pass through the low pH environment of the stomach, and effectively colonize the intestinal epithelium downstream. Here, we investigated the effect of a multilayer coating containing red ginseng dietary fiber, on the acid tolerance, and the adhesion and proliferation capacities of three Lactobacillus strains (Limosilactobacillus reuteri KGC1901, Lacticaseibacillus casei KGC1201, Limosilactobacillus fermentum KGC1601) isolated from Panax ginseng, using HT-29 cells, mucin-coated plates, and human pluripotent stem cell-derived intestinal epithelial cells as in vitro models of human gut physiology. We observed that the multilayer-coated strains displayed improved survival rates after passage through gastric juice, as well as high adhesion and proliferation capacities within the various gut epithelial systems tested, compared to their uncoated counterparts. Our findings demonstrated that the multilayer coat effectively protected commensal microbiota and led to improved adhesion and colonization of intestinal epithelial cells, and consequently to higher probiotic efficacy.
Ye-Ji Jang;Jin Seok Moon;Ji Eun Kim;Dayoung Kim;Han Sol Choi;Ikhoon Oh
Food Science of Animal Resources
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v.44
no.1
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pp.119-131
/
2024
BIOVITA 3 bacterial species (BIOVITA 3), a probiotic blend powder containing Clostridium butyricum IDCC 1301, Weizmannia coagulans IDCC 1201, and Bacillus subtilis IDCC 1101, has been used as a food ingredient for gut health. However, its efficacy in improving constipation has not been reported. Therefore, we aimed to investigate the functional effects of oral administration of BIOVITA 3 as well as its component strains alone (at 1.0×109 CFU/day) in Sprague-Dawley (SD) rats with loperamide-induced constipation. The study included fecal analysis, gastrointestinal transit ratio, histopathological analysis, short chain fatty acids (SCFAs), and metagenome analysis. As results, the BIOVITA 3 group showed significant improvements in fecal number, water content, gastrointestinal transit ratio, and thickening of the mucosal layer. In the SCFAs analysis, all probiotic-treated groups showed an increase in total SCFAs compared to the loperamide-constipated group. Changes in microbial abundance and the diversity index of three groups (normal, constipated, and BIOVITA 3) were also defined. Of these, the BIOVITA 3 showed a significant improvement in loperamide-constipated SD-rats. This study suggests the possibility that BIOVITA 3 can be applied as an ingredient in functional foods to relieve constipation.
Kim, In Sung;Lee, Seung Ho;Kwon, Young Min;Adhikari, Bishnu;Kim, Jeong A;Yu, Da Yoon;Kim, Gwang Il;Lim, Jong Min;Kim, Sung Hak;Lee, Sang Suk;Moon, Yang Soo;Choi, In Soon;Cho, Kwang Keun
Journal of Microbiology and Biotechnology
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v.29
no.11
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pp.1693-1706
/
2019
Atopic dermatitis (AD) is a chronic inflammatory skin disease of mainly infants and children. Currently, the development of safe and effective treatments for AD is urgently required. The present study was conducted to investigate the immunomodulatory effects of yeast-extracted β-1,3/1,6-glucan and/or Lactobacillus plantarum (L. plantarum) LM1004 against AD-like symptoms. To purpose, β-1,3/1,6-glucan and/or L. plantarum LM1004 were orally administered to AD-induced animal models of rat (histamine-induced vasodilation) and mouse (pruritus and contact dermatitis) exhibiting different symptoms of AD. We then investigated the treatment effects on AD-like symptoms, gene expression of immune-related factors, and gut microbiomes. Oral administration of β-1,3/1,6-glucan (0.01 g/kg initial body weight) and/or 2 × 1012 cells/g L. plantarum LM1004 (0.01 g/kg initial body weight) to AD-induced animal models showed significantly reduced vasodilation in the rat model, and pruritus, edema, and serum histamine in the mouse models (p < 0.05). Interestingly, β-1,3/1,6-glucan and/or L. plantarum LM1004 significantly decreased the mRNA levels of Th2 and Th17 cell transcription factors, while the transcription factors of Th1 and Treg cells, galactin-9, filaggrin increased, which are indicative of enhanced immunomodulation (p < 0.05). Moreover, in rats with no AD induction, the same treatments significantly increased the relative abundance of phylum Bacteroidetes and the genus Bacteroides. Furthermore, bacterial taxa associated with butyrate production such as, Lachnospiraceae and Ruminococcaceae at family, and Roseburia at genus level were increased in the treated groups. These findings suggest that the dietary supplementation of β-1,3/1,6-glucan and/or L. plantarum LM1004 has a great potential for treatment of AD as well as obesity in humans through mechanisms that might involve modulation of host immune systems and gut microbiota.
Obesity is associated with impaired intestinal epithelial barrier function, which contribute to host systemic inflammation and metabolic dysfunction. Korean traditional foods, fiber-rich bean products, have been various biological activities in anti-inflammatory responses, but has not reported the large intestinal health. In this study, we investigated the intestinal health promoting effect of cooked soybeans (CSB) on high fat diet (HFD)-induced obesity model. SD rat were fed either a HFD or HFD supplemented with 10.6% CSB (HFD+CSB) for animal experimental period. CSB treatment significantly decreased the HFD-induced weights of body and fat. Also, CSB treatment improved HFD-reduced tight junction components (ZO-1, Claudin-1, and Occludin-1) mRNA expression in large intestine tissue. Additionally, histopathological evaluation showed that CSB treatment attenuated the HFD-increased inflammatory cells infiltration and epithelial damages in large intestine tissue. At the genus level, effects of CSB supplement not yet clear, while dietary effects showed differential abundance of several genera including Lactobacillus, Duncaniella, and Alloprevotella. NMDS analysis showed significant microbial shifts by HFD, while CSB did not shift gut microbiota. CSB increased the abundance of the genera Anaerotignum, Enterococcus, Clostridium sensu stricto, and Escherichia/Shigella by linear discriminant analysis effect size analysis, while reduced the abundance of Longicatena and Ligilactobacillus. These findings indicate that CSB supplement improves HFD-deteriorated large intestinal health by the amelioration of tight junction component, while CSB did not shift gut microbiotas.
The potential for ochratoxin A (OTA) degradation by swine intestinal microbiota was assessed in the current study. Intestinal content that was collected aseptically from swine was spiked with 100 ppb OTA and incubated for 6 and 12 h at $39^{\circ}C$. An OTA assay was conducted using the incubated samples, and it was found that 20% of the OTA toxin was detoxified, indicating the presence of microbes capable of OTA degradation. Twenty-eight bacterial species were isolated anaerobically in M 98-5 media and 45 bacterial species were isolated using nutrient broth aerobically. Screening results showed that one anaerobic bacterial isolate, named MM11, detoxified more than 75% of OTA in liquid media. Furthermore, 1.0 ppm OTA was degraded completely after 24 h incubation on a solid 'corn' substrate. The bacterium was identified by 16S rDNA sequencing as having 97% sequence similarity with Eubacterium biforme. The isolation of an OTA-degrading bacterium from the swine natural flora is of great importance for OTA biodegradation and may be a valuable potential source for OTA-degradation enzymes in industrial applications.
To understand the metabolism of flavonoid rhamnoglycosides by human intestinal microbiota, we measured the metabolic activity of rutin and poncirin (distributed in many functional foods and herbal medicine) by 100 human stool specimens. The average α-L-rhamnosidase activities on the p-nitrophenyl-α-L-rhamnopyranoside, rutin, and poncirin subtrates were 0.10 ± 0.07, 0.25 ± 0.08, and 0.15 ± 0.09 pmol/min/mg, respectively. To investigate the enzymatic properties, α-L-rhamnosidase-producing bacteria were isolated from the specimens, and the α-L-rhamnosidase gene was cloned from a selected organism, Bifidobacterium dentium, and expressed in E. coli. The cloned α-L-rhamnosidase gene contained a 2,673 bp sequcence encoding 890 amino acid residues. The cloned gene was expressed using the pET 26b(+) vector in E. coli BL21, and the expressed enzyme was purified using Ni2+-NTA and Q-HP column chromatography. The specific activity of the purified α-L-rhamnosidase was 23.3 µmol/min/mg. Of the tested natural product constituents, the cloned α-L-rhamnosidase hydrolyzed rutin most potently, followed by poncirin, naringin, and ginsenoside Re. However, it was unable to hydrolyze quercitrin. This is the first report describing the cloning, expression, and characterization of α-L-rhamnosidase, a flavonoid rhamnoglycosidemetabolizing enzyme, from bifidobacteria. Based on these findings, the α-L-rhamnosidase of intestinal bacteria such as B. dentium seem to be more effective in hydrolyzing (1 →6) bonds than (1 →2) bonds of rhamnoglycosides, and may play an important role in the metabolism and pharmacological effect of rhamnoglycosides.
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