Objective: Weaning is an important stage in the life of young mammals, which is associated with intestinal inflammation, gut microbiota disorders, and even death. β-Carotene displays anti-inflammatory and antioxidant activities, which can prevent the development of inflammatory diseases. However, whether β-carotene can affect intestinal microbiota remains unclear. Methods: Twenty-four piglets were distributed into four groups: the normal suckling group (Con), the weaning group (WG), the weaning+β-carotene (40 mg/kg) group (LCBC), and the weaning+β-carotene (80 mg/kg) group (HCBC). The serum, jejunum, colon, and faeces were collected separately from each group. The effects of β-carotene on the phenotype, overall structure, and composition of gut microbiota were assessed in weaning piglets. Results: The results showed that β-carotene improved the growth performance, intestinal morphology and relieved inflammation. Furthermore, β-carotene significantly decreased the species from phyla Bacteroidetes and the genus Prevotella, and Blautia, and increased the species from the phyla Firmicutes and the genera p-75-a5, and Parabacteroides compared to the WG group. Spearman's correlation analysis showed that Prevotella and Blautia were positively correlated, and Parabacteroides and Synergistes were negatively correlated with the levels of interleukin-1β (IL-1β), IL-6, and tumour necrosis factor-α (TNF-α), while p-75-a5 showed negative correlation with IL-6 in serum samples from piglets. Conclusion: These findings indicate that β-carotene could alleviate weaning-induced intestinal inflammation by modulating gut microbiota in piglets. Prevotella may be a potential target of β-carotene in alleviating the weaning-induced intestinal inflammation in piglets.
Livestock species experience several stresses, particularly weaning, transportation, overproduction, crowding, temperature, and diseases in their life. Heat stress (HS) is one of the most stressors, which is encountered in livestock production systems throughout the world, especially in the tropical regions and is likely to be intensified due to global rise in environmental temperature. The gut has emerged as one of the major target organs affected by HS. The alpha- and beta-diversity of gut microbiota composition are altered due to heat exposure to animals with greater colonization of pathogenic microbiota groups. HS also induces several changes in the gut including damages of microstructures of the mucosal epithelia, increased oxidative insults, reduced immunity, and increased permeability of the gut to toxins and pathogens. Vulnerability of the intestinal barrier integrity leads to invasion of pathogenic microbes and translocation of antigens to the blood circulations, which ultimately may cause systematic inflammations and immune responses. Moreover, digestion of nutrients in the guts may be impaired due to reduced enzymatic activity in the digesta, reduced surface areas for absorption and injury to the mucosal structure and altered expressions of the nutrient transport proteins and genes. The systematic hormonal changes due to HS along with alterations in immune and inflammatory responses often cause reduced feed intake and production performance in livestock and poultry. The altered microbiome likely orchestrates to the hosts for various relevant biological phenomena occurring in the body, but the exact mechanisms how functional communications occur between the microbiota and HS responses are yet to be elucidated. This review aims to discuss the effects of HS on microbiota composition, mucosal structure, oxidant-antioxidant balance mechanism, immunity, and barrier integrity in the gut, and production performance of farm animals along with the dietary ameliorations of HS. Also, this review attempts to explain the mechanisms how these biological responses are affected by HS.
Da Yoon, Yu;Sang-Hyon, Oh;In Sung, Kim;Gwang Il, Kim;Jeong A, Kim;Yang Soo, Moon;Jae Cheol, Jang;Sang Suk, Lee;Jong Hyun, Jung;Hwa Chun, Park;Kwang Keun, Cho
Animal Bioscience
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v.36
no.1
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pp.156-166
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2023
Objective: In this study, we investigated the effects of Rubus coreanus-derived lactic acid bacteria (LAB) fermented feed (RC-LAB fermented feed) and three types of LAB (Lactobacillus plantarum, Lactobacillus acidophilus, Bifidobacterium animalis) on the expression of transcription factors and cytokines in Th1, Th2, Th17, and Treg cells in the intestinal lymph nodes and spleens of rats. In addition, the effect on intestinal microbiota composition and body weight was investigated. Methods: Five-week-old male rats were assigned to five treatments and eight replicates. The expression of transcription factors and cytokines of Th1, Th2, Th17, and Treg cells in the intestinal lymph nodes and spleens was analyzed using real-time reverse transcriptase polymerase chain reaction assays. Intestinal tract microbiota compositions were analyzed by next-generation sequencing and quantitative polymerase chain reaction assays. Results: RC-LAB fermented feed and three types of LAB increased the expression of transcription factors and cytokines in Th1, Treg cells and Galectin-9, but decreased in Th2 and Th17 cells. In addition, the intestinal microbiota composition changed, the body weight and Firmicutes to Bacteroidetes (F/B) ratio decreased, and the relative abundance of LAB increased. Conclusion: LAB fermented feed and three types of LAB showed an immune modulation effect by inducing T cell polarization and increased LAB in the intestinal microbiota.
Background: Gut microbiota influence the central nervous system through gut-brain-axis. They also affect the neurological disorders. Gut microbiota differs in patients with Alzheimer's disease (AD), as a potential factor that leads to progression of AD. Oral intake of Korean Red Ginseng (KRG) improves the cognitive functions. Therefore, it can be proposed that KRG affect the microbiota on the gut-brain-axis to the brain. Methods: Tg2576 were used for the experimental model of AD. They were divided into four groups: wild type (n = 6), AD mice (n = 6), AD mice with 30 mg/kg/day (n = 6) or 100 mg/kg/day (n = 6) of KRG. Following two weeks, changes in gut microbiota were analyzed by Illumina HiSeq4000 platform 16S gene sequencing. Microglial activation were evaluated by quantitative Western blot analyses of Iba-1 protein. Claudin-5, occludin, laminin and CD13 assay were conducted for Blood-brain barrier (BBB) integrity. Amyloid beta (Aβ) accumulation demonstrated through Aβ 42/40 ratio was accessed by ELISA, and cognition were monitored by Novel object location test. Results: KRG improved the cognitive behavior of mice (30 mg/kg/day p < 0.05; 100 mg/kg/day p < 0.01), and decreased Aβ 42/40 ratio (p < 0.01) indicating reduced Aβ accumulation. Increased Iba-1 (p < 0.001) for reduced microglial activation, and upregulation of Claudin-5 (p < 0.05) for decreased BBB permeability were shown. In particular, diversity of gut microbiota was altered (30 mg/kg/day q-value<0.05), showing increased population of Lactobacillus species. (30 mg/kg/day 411%; 100 mg/kg/day 1040%). Conclusions: KRG administration showed the Lactobacillus dominance in the gut microbiota. Improvement of AD pathology by KRG can be medicated through gut-brain axis in mice model of AD.
Objective: The observation that temperate C3 and tropical C4 forage silages easily produce large amounts of ethanol or acetic acid has puzzled researchers for many years. Hence, this study aimed to assess the effects of epiphytic microbiota from C3 forages (Italian ryegrass and oat) on fermentative products and bacterial community structure in C4 forage (sorghum) silage. Methods: Through microbiota transplantation and γ-ray irradiation sterilization, the irradiated sorghum was treated: i) sterile distilled water (STSG); ii) epiphytic microbiota from sorghum (SGSG); iii) epiphytic microbiota from Italian ryegrass (SGIR); iv) epiphytic microbiota from oat (SGOT). Results: After 60 days, all the treated groups had high lactic acid (>63.0 g/kg dry matter [DM]) contents and low pH values (<3.70), acetic acid (<14.0 g/kg DM) and ammonia nitrogen (<80.0 g/kg total nitrogen) contents. Notably, SGIR (59.8 g/kg DM) and SGOT (77.6 g/kg DM) had significantly (p<0.05) higher ethanol concentrations than SGSG (14.2 g/kg DM) on day 60. After 60 days, Lactobacillus were predominant genus in three treated groups. Higher proportions of Chishuiella (12.9%) and Chryseobacterium (7.33%) were first found in silages. The ethanol contents had a positive correlation (p<0.05) with the abundances of Chishuiella, Acinetobacter, Stenotrophomonas, Chryseobacterium, and Sphingobacterium. Conclusion: The epiphytic bacteria on raw materials played important roles in influencing the silage fermentation products between temperate C3 and tropical C4 forages. The quantity and activity of hetero-fermentative Lactobacillus, Chishuiella, Acinetobacter, Stenotrophomonas, Chryseobacterium, and Sphingobacterium may be the key factors for the higher ethanol contents and DM loss in silages.
Purpose: Ketogenic diets (KDs) have anti-obesity effects that may be related to glucose control and the gut microbiota. This paper hypothesizes that KD reduces body weight and changes the insulin sensitivity and gut microbiota composition in a mouse model of diet-induced obesity. Methods: In this study, C57BL/6 male mice were assigned randomly to 3 groups. The assigned diets were provided to the control and high-fat (HF) diet groups for 14 weeks. The KD group was given a HF diet for 8 weeks to induce obesity, followed by feeding the KD for the next 6 weeks. Results: After the treatment period, the KD group exhibited a 35.82% decrease in body weight gain compared to the HF group. In addition, the KD group demonstrated enhanced glucose control, as shown by the lower levels of serum fasting glucose, serum fasting insulin, and the homeostatic model assessment of insulin resistance, compared to the HF group. An analysis of the gut microbiota using 16S ribosomal RNA sequencing revealed a significant decrease in the proportion of Firmicutes when the KD was administered. In addition, feeding the KD reduced the overall alpha-diversity measures and caused a notable separation of microbial composition compared to the HF diet group. The KD also led to a decrease in the relative abundance of specific species, such as Acetatifactor_muris, Ligilactobacillus_apodemi, and Muribaculum_intestinale, compared with the HF group. These species were positively correlated with the body weight, whereas the abundant species in the KD group (Kineothrix_alysoides and Saccharofermentans_acetigenes) showed a negative correlation with body weight. Conclusion: The current study presents supporting evidence that KD reduced the body weight and altered the insulin sensitivity and gut microbiota composition in a mouse model of diet-induced obesity.
Proceedings of the Plant Resources Society of Korea Conference
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2020.12a
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pp.80-80
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2020
Glycyrrhizae Radix (GR), commomly known as liquorice, is a medicinal and edible plant widely used in East Asia with its pharmacological properties. Currently, Glycyrrhiza uralensis, G. glabra and G. inflata are used for pharmaceutical purposes in Korea and then the improved Glycyrrhiza varieties, WON-GAM (WG) has been developed by Korea Rural Development Administration. To evaluate equivalence of efficacy, several comparative studies between already-registered species and new cultivars have been conducted. To evaluate equivalence of efficacy, several comparative studies between already-registered species and new cultivars have been conducted. The aim of this study was to evaluate the effect of WG on fecal microbiota in DSS-induced colitis model. Fecal microbiota was analyzed by terminal restriction fragment length polymorphism (T-RFLP). The composition of the fecal microbiota did not show a specific pattern based on experimental groups; however, a tendency toward an increase in the proportion of Lactobacillales was observed. Glycyrrhiza varieties could change composition of fecal microbiota in DSS-induced colitis model. This work was carried out with the support of "Cooperative Research Program for Agriculture Science and Technology Development (Project No. PJ014246022020)" Rural Development Administration.
The diverse microbial communities that colonize distinct segments of the gastrointestinal tract are intimately related to aspects of physiology and the pathology of human health. However, most recent studies have focused on the rectal or fecal microbiota, and the microbial signature of the duodenum is poorly studied. In this study, we compared the microbiota in duodenal and rectal samples to illustrate the characteristic microbial signatures of the duodenum in healthy adults. Nine healthy volunteers donated biopsies and luminal contents from the duodenum and rectum. To determine the composition and diversity of the microbiota, 454-pyrosequencing of bacterial 16S rRNA was performed and multiple bioinformatics analyses were applied. The α-diversity and phylogenetic diversity of the microbiota in the duodenal samples were higher than those of the rectal samples. There was higher biodiversity among the microbiota isolated from rectal biopsies than feces. Proteobacteria were more highly represented in the duodenum than in the rectum, both in the biopsies and in the luminal contents from the healthy volunteers (38.7% versus 12.5%, 33.2% versus 5.0%, respectively). Acinetobacter and Prevotella were dominant in the duodenum, whereas Bacteroides and Prevotella were dominant in the rectum. Additionally, the percentage of OTUs shared in biopsy groups was far higher than in the luminal group (43.0% versus 26.8%) and a greater number of genera was shared among the biopsies than the luminal contents. Duodenal samples demonstrated greater biological diversity and possessed a unique microbial signature compared with the rectum. The mucosa-associated microbiota was more relatively conserved than luminal samples.
Alcohol dependence is a global public health problem, yet the mechanisms of alcohol dependence are incompletely understood. The traditional view has been that ethanol alters various neurotransmitters and their receptors in the brain and causes the addiction. However, an increasing amount of experimental evidence suggests that gut microbiota also influence brain functions via gut-to-brain interactions, and may therefore induce the development of alcohol use disorders. In this study, a rat model of alcohol dependence and withdrawal was employed, the gut microbiota composition was analyzed by high-throughput 16S rRNA gene sequencing, and the metagenome function was predicted by PICRUSt software. The results suggested that chronic alcohol consumption did not significantly alter the diversity and richness of gut microbiota in the jejunum and colon, but rather markedly changed the microbiota composition structure in the colon. The phyla Bacteroidetes and eight genera including Bacteroidales S24-7, Ruminococcaceae, Parabacteroides, Butyricimonas, et al were drastically increased, however the genus Lactobacillus and gauvreauii in the colon were significantly decreased in the alcohol dependence group compared with the withdrawal and control groups. The microbial functional prediction analysis revealed that the proportions of amino acid metabolism, polyketide sugar unit biosynthesis and peroxisome were significantly increased in the AD group. This study demonstrated that chronic alcohol consumption has a dramatic effect on the microbiota composition structure in the colon but few effects on the jejunum. Inducement of colonic microbiota dysbiosis due to alcohol abuse seems to be a factor of alcohol dependence, which suggests that modulating colonic microbiota composition might be a potentially new target for treating alcohol addiction.
The hindgut of horses is an anaerobic fermentative chamber for a complex and dynamic microbial population, which plays a critical role in health and energy requirements. Research on the gut microbiota of Mongolian horses has not been reported until now as far as we know. Mongolian horse is a major local breed in China. We performed high-throughput sequencing of the 16S rRNA genes V4 hypervariable regions from gut fecal material to characterize the gut microbiota of Mongolian horses and compare them to the microbiota in Thoroughbred horses. Fourteen Mongolian and 19 Thoroughbred horses were used in the study. A total of 593,678 sequence reads were obtained from 33 samples analyzed, which were found to belong to 16 phyla and 75 genera. The bacterial community compositions were similar for the two breeds. Firmicutes (56% in Mongolian horses and 53% in Thoroughbred horses) and Bacteroidetes (33% and 32% respectively) were the most abundant and predominant phyla followed by Spirochaete, Verrucomicrobia, Proteobacteria, and Fibrobacteres. Of these 16 phyla, five (Synergistetes, Planctomycetes, Proteobacteria, TM7, and Chloroflexi) were significantly different (p<0.05) between the two breeds. At the genus level, Treponema was the most abundant genus (43% in Mongolian horses vs 29% in Thoroughbred horses), followed by Ruminococcus, Roseburia, Pseudobutyrivibrio, and Anaeroplasma, which were detected in higher distribution proportion in Mongolian horses than in Thoroughbred horses. In contrast, Oscillibacter, Fibrobacter, Methanocorpusculum, and Succinivibrio levels were lower in Mongolian horses. Among 75 genera, 30 genera were significantly different (p<0.05) between the two breeds. We found that the environment was one of very important factors that influenced horse gut microbiota. These findings provide novel information about the gut microbiota of Mongolian horses and a foundation for future investigations of gut bacterial factors that may influence the development and progression of gastrointestinal disease in horses.
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