• Journal of Microbiology and Biotechnology
• /
• 제34권6호
• /
• pp.1287-1298
• /
• 2024

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that is currently difficult to treat effectively. Both Bacillus natto (BN) and ginseng-soluble dietary fiber (GSDF) are anti-inflammatory and helps sustain the intestinal barrier. In this study, the protective effects and mechanism of the combination of B. natto JLCC513 and ginseng-soluble dietary fiber (BG) in DSS-induced UC mice were investigated. Intervention with BG worked better than taking BN or GSDF separately, as evidenced by improved disease activity index, colon length, and colon injury and significantly reduced the levels of oxidative and inflammatory factors (LPS, ILs, and TNF-α) in UC mice. Further mechanistic study revealed that BG protected the intestinal barrier integrity by maintaining the tight junction proteins (Occludin and Claudin1) and inhibited the LPS/TLR4/NF-κB pathway in UC mice. In addition, BG increased the abundance of beneficial bacteria such as Bacteroides and Turicibacter and reduced the abundance of harmful bacteria such as Allobaculum in the gut microbiota of UC mice. BG also significantly upregulated genes related to linoleic acid metabolism in the gut microbiota. These BG-induced changes in the gut microbiota of mice with UC were significantly correlated with changes in pathological indices. In conclusion, this study demonstrated that BG exerts protective effect against UC by regulating the LPS/TLR4/NF-κB pathway and the structure and metabolic function of gut microbiota. Thus, BG can be potentially used in intestinal health foods to treat UC.

• Journal of Microbiology and Biotechnology
• /
• 제32권12호
• /
• pp.1497-1505
• /
• 2022

Recently, the concept of personalized nutrition has been developed, which states that food components do not always lead to the same metabolic responses, but vary from person to person. Although this concept has been studied based on individual genetic backgrounds, researchers have recently explored its potential role in the gut microbiome. The gut microbiota physiologically communicates with humans by forming a bidirectional relationship with the micronutrients, macronutrients, and phytochemicals consumed by the host. Furthermore, the gut microbiota can vary from person to person and can be easily shifted by diet. Therefore, several recent studies have reported the application of personalized nutrition to intestinal microflora. This review provides an overview of the interaction of diet with the gut microbiome and the latest evidence in understanding the inter-individual differences in dietary responsiveness according to individual baseline gut microbiota and microbiome-associated dietary intervention in diseases. The diversity of the gut microbiota and the presence of specific microorganisms can be attributed to physiological differences following dietary intervention. The difference in individual responsiveness based on the gut microbiota has the potential to become an important research approach for personalized nutrition and health management, although further well-designed large-scale studies are warranted.

• Journal of Digestive Cancer Research
• /
• 제10권1호
• /
• pp.31-38
• /
• 2022

Ulcerative colitis (UC) exhibits chronic intestinal inflammatory conditions with cycles of relapse and remission. The incidence is rapidly growing in Asian countries including South Korea possibly due to changes in lifestyles. Although the etiology of inflammatory bowel disease is inconclusive, gut microbiota composition is considered a critical factor involved in the pathogenesis of UC. The overgrowth of pathogenic bacteria evokes hyper-immune responses in gut epithelium causing tissue inflammation and damage. Also, failure to regulate gut epithelium integrity due to chronic inflammation and mucus depletion accelerates bacterial translocation aggravating immune dysregulation. Gut microbiota composition responds to the diet in a very rapid manner. Epidemiological studies have indicated that the risk of UC is associated with low plant foods/high animal foods consumption. Several bacterial strains consistently found depleted in UC patients use plant food-originated dietary fiber producing short chain fatty acids to maintain epithelial integrity. These bacteria also use mucus layer mucin to keep gut microbiota diversity. These studies partly explain the association between dietary modification of gut microbiota in UC development. Further human intervention trials are required to allow the use of specific bacterial strains in the management of UC.

• Molecules and Cells
• /
• 제42권4호
• /
• pp.313-320
• /
• 2019

Intraepithelial lymphocytes (IELs) develop through the continuous interaction with intestinal antigens such as commensal microbiome and diet. However, their respective roles and mutual interactions in the development of IELs are largely unknown. Here, we showed that dietary antigens regulate the development of the majority of $CD8{\alpha}{\beta}$ IELs in the small intestine and the absence of commensal microbiota particularly during the weaning period, delay the development of IELs. When we tested specific dietary components, such as wheat or combined corn, soybean and yeast, they were dependent on commensal bacteria for the timely development of diet-induced $CD8{\alpha}{\beta}$ IELs. In addition, supplementation of intestinal antigens later in life was inefficient for the full induction of $CD8{\alpha}{\beta}$ IELs. Overall, our findings suggest that early exposure to commensal bacteria is important for the proper development of dietary antigen-dependent immune repertoire in the gut.

• 생명과학회지
• /
• 제27권11호
• /
• pp.1290-1298
• /
• 2017

인체의 장내에 존재하는 장내 미생물은 서로 공생 또는 길항 관계를 유지하며 우리 몸의 면역 방어 기전에 중요한 요소로 작용한다. 본 연구는 항암제가 위암 환자의 장내 미생물 생태계에 미치는 영향을 조사 하였다. 항암치료를 받는 환자의 분변에서 genomic DNA를 추출하고, 16S rDNA 유전자에 대한 denaturing gradient gel electrophoresis (DGGE)를 수행하였다. 분석된 균주는 개체간의 차이가 있었으나, 대부분 사람의 장내에 살고 있는 normal flora로 동정되었다. 모든 분변에 존재하는 5 개 밴드의 서열 분석 결과에 의하면 Faecalibacterium prausnitzii, Morganella morganii 및 Uncultured bacterium sp.가 나타났고, 항암제 처리 후 Sphingomonas paucimobilis, Lactobacillus gasseri, Parabacteroides distasonis 및 Enterobacter sp.가 증가하였다. 이 연구에서 probiotic으로 알려진 Bifidobacterium과 Lactobacillus를 특이적 PCR primer를 이용하여 동정한 결과, 항암제 투여로 인해 Bifidobacterium과 Lactobacillus의 개체군이 현저하게 줄어들어 diarrhea와 같은 부작용의 원인을 예상하게 하며, 장내 생태계의 주요 박테리아 집단에도 중요한 영향을 미치는 것을 알 수 있었다. 이러한 결과는 항암제 투여와 같이 시간의 흐름에 따른 균총의 변화를 시각적으로 모니터링하기 위하여 PCR-DGGE 분석법이 유용하다는 것을 나타낸다.

• Journal of Animal Science and Technology
• /
• 제63권6호
• /
• pp.1314-1327
• /
• 2021

Bacillus is characterized by the formation of spores in harsh environments, which makes it suitable for use as a probiotic for feed because of thermostability and high survival rate, even under long-term storage. This study was conducted to investigate the effects of Bacillus-based probiotics on growth performance, nutrient digestibility, intestinal morphology, immune response, and intestinal microbiota of weaned pigs. A total of 40 weaned pigs (7.01 ± 0.86 kg body weight [BW]; 28 d old) were randomly assigned to two treatments (4 pigs/pen; 5 replicates/treatment) in a randomized complete block design (block = BW and sex). The dietary treatment was either a typical nursery diet based on corn and soybean meal (CON) or CON supplemented with 0.01% probiotics containing a mixture of Bacillus subtilis and Bacillus licheniformis (PRO). Fecal samples were collected daily by rectal palpation for the last 3 days after a 4-day adaptation. Blood, ileal digesta, and intestinal tissue samples were collected from one pig in each pen at the respective time points. The PRO group did not affect the feed efficiency, but the average daily gain was significantly improved (p < 0.05). The PRO group showed a trend of improved crude protein digestibility (p < 0.10). The serum transforming growth factor-β1 level tended to be higher (p < 0.10) in the PRO group on days 7 and 14. There was no difference in phylum level of the intestinal microbiota, but there were differences in genus composition and proportions. However, β-diversity analysis showed no statistical differences between the CON and the PRO groups. Taken together, Bacillus-based probiotics had beneficial effects on the growth performance, immune system, and intestinal microbiota of weaned pigs, suggesting that Bacillus can be utilized as a functional probiotic for weaned pigs.

• Clinical and Experimental Pediatrics
• /
• 제61권7호
• /
• pp.217-220
• /
• 2018

Purpose: Type 1 diabetes mellitus (T1DM) is a chronic and immune-mediated disease, which is characterized by the progressive destruction of pancreatic beta cells. T1DM precipitates in genetically susceptible individuals through environmental factors. In this study, we aimed to evaluate the impact of autoimmunity and intestinal colonization of Candida albicans on the development of T1DM. Methods: Forty-two patients newly diagnosed with T1DM and 42 healthy subjects were included in this monocentric study. The basic and clinical characteristics of the patients were recorded. T1DM-, thyroid-, and celiac-associated antibodies were evaluated. Stool cultures for C. albicans were performed to assess whether or not gut integrity was impaired in patients with T1DM. Results: The evaluation of T1DM- and thyroid-associated antibodies showed that the prevalences of islet cell antibodies and antithyroperoxidase positivity were higher in the study patients than in the patients in the control group. Furthermore, the direct examination and culture of fresh stool samples revealed that 50% of the patients with T1DM and 23.8% of the control subjects had fungi (C. albicans). Conclusion: Through this study, we suggest that the presence of intestinal C. albicans colonization at the time of the diagnosis of T1DM may indicate impairment of normal intestinal microbiota. We also suggest that there may be a tendency of T1DM in patients with a high prevalence of intestinal C. albicans.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• 제18권4호
• /
• pp.230-237
• /
• 2015

Purpose: Various gastrointestinal factors may contribute to maladaptive behavior in children with autism spectrum disorders (ASD). To determine the association between maladaptive behavior in children with ASD and gastrointestinal symptoms such as severity, intestinal microbiota, inflammation, enterocyte damage, permeability and absorption of opioid peptides. Methods: This observational cross-sectional study compared children with ASD to healthy controls, aged 2-10 years. Maladaptive behavior was classified using the Approach Withdrawal Problems Composite subtest of the Pervasive Developmental Disorder Behavior Inventory. Dependent variables were gastrointestinal symptom severity index, fecal calprotectin, urinary D-lactate, urinary lactulose/mannitol excretion, urinary intestinal fatty acids binding protein (I-FABP) and urinary opioid peptide excretion. Results: We did not find a significant difference between children with ASD with severe or mild maladaptive behavior and control subjects for gastrointestinal symptoms, fecal calprotectin, urinary D-lactate, and lactulose/mannitol ratio. Urinary opioid peptide excretion was absent in all children. Children with ASD with severe maladaptive behavior showed significantly higher urinary I-FABP levels compared to those with mild maladaptive behavior (p=0.019) and controls (p=0.015). Conclusion: In our series, maladaptive behavior in ASD children was not associated with gastrointestinal symptoms, intestinal inflammation (no difference in calprotectin), microbiota (no difference in urinary D-lactate) and intestinal permeability (no difference in lactulose/manitol ratio). ASD children with severe maladaptive behavior have significantly more enterocyte damage (increased urinary I-FABP) than ASD children with mild maladaptive behavior and normal children.

• 식품과학과 산업
• /
• 제47권4호
• /
• pp.2-7
• /
• 2014

• Journal of Yeungnam Medical Science
• /
• 제38권1호
• /
• pp.27-33
• /
• 2021

The gut is a complex organ that has played an important role in digestion, absorption, endocrine functions, and immunity. The gut mucosal barriers consist of the immunologic barrier and nonimmunologic barrier. During critical illnesses, the gut is susceptible to injury due to the induction of intestinal hyperpermeability. Gut hyperpermeability and barrier dysfunction may lead to systemic inflammatory response syndrome. Additionally, gut microbiota are altered during critical illnesses. The etiology of such microbiome alterations in critical illnesses is multifactorial. The interaction or systemic host defense modulation between distant organs and the gut microbiome is increasingly studied in disease research. No treatment modality exists to significantly enhance the gut epithelial integrity, permeability, or mucus layer in critically ill patients. However, multiple helpful approaches including clinical and preclinical strategies exist. Enteral nutrition is associated with an increased mucosal barrier in animal and human studies. The trophic effects of enteral nutrition might help to maintain the intestinal physiology, prevent atrophy of gut villi, reduce intestinal permeability, and protect against ischemia-reperfusion injury. The microbiome approach such as the use of probiotics, fecal microbial transplantation, and selective decontamination of the digestive tract has been suggested. However, its evidence does not have a high quality. To promote rapid hypertrophy of the small bowel, various factors have been reported, including the epidermal growth factor, membrane permeant inhibitor of myosin light chain kinase, mucus surrogate, pharmacologic vagus nerve agonist, immune-enhancing diet, and glucagon-like peptide-2 as preclinical strategies. However, the evidence remains unclear.