• Biomolecules & Therapeutics
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• v.27 no.2
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• pp.134-144
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• 2019

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased with the incidence of obesity; however, the underlying mechanisms are unknown. In this study, high-resolution metabolomics (HRM) along with transcriptomics were applied on animal models to draw a mechanistic insight of NAFLD. Wild type (WT) and catalase knockout (CKO) mice were fed with normal fat diet (NFD) or high fat diet (HFD) to identify the changes in metabolic and transcriptomic profiles caused by catalase gene deletion in correspondence with HFD. Integrated omics analysis revealed that cholic acid and $3{\beta}$, $7{\alpha}$-dihydroxy-5-cholestenoate along with cyp7b1 gene involved in primary bile acid biosynthesis were strongly affected by HFD. The analysis also showed that CKO significantly changed all-trans-5,6-epoxy-retinoic acid or all-trans-4-hydroxy-retinoic acid and all-trans-4-oxo-retinoic acid along with cyp3a41b gene in retinol metabolism, and ${\alpha}/{\gamma}$-linolenic acid, eicosapentaenoic acid and thromboxane A2 along with ptgs1 and tbxas1 genes in linolenic acid metabolism. Our results suggest that dysregulated primary bile acid biosynthesis may contribute to liver steatohepatitis, while up-regulated retinol metabolism and linolenic acid metabolism may have contributed to oxidative stress and inflammatory phenomena in our NAFLD model created using CKO mice fed with HFD.

• Journal of Ginseng Research
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• v.46 no.6
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• pp.780-789
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• 2022

Background: Incretin impairment, characterized by insufficient secretion of L-cell-derived glucagon-like peptide-1 (GLP-1), is a defining step of type 2 diabetes mellitus (T2DM). Ginsenoside compound K (CK) can stimulate GLP-1 secretion; however, the potential mechanism underlying this effect has not been established. Methods: CK (40 mg/kg) was administered orally to male db/db mice for 4 weeks. The body weight, oral glucose tolerance, GLP-1 secretion, gut microbiota sequencing, bile acid (BA) profiles, and BA synthesis markers of each subject were then analyzed. Moreover, TGR5 expression was evaluated by immunoblotting and immunofluorescence, and L-cell lineage markers involved in L-cell abundance were analyzed. Results: CK ameliorated obesity and impaired glucose tolerance in db/db mice by altering the gut microbiota, especially Ruminococcaceae family, and this changed microbe was positively correlated with secondary BA synthesis. Additionally, CK treatment resulted in the up-regulation of CYP7B1 and CYP27A1 and the down-regulation of CYP8B1, thereby shifting BA biosynthesis from the classical pathway to the alternative pathway. CK altered the BA pool by mainly increasing LCA and DCA. Furthermore, CK induced L-cell number expansion leading to enhanced GLP-1 release through TGR5 activation. These increases were supported by the upregulation of genes governing GLP-1 secretion and L-cell differentiation. Conclusions: The results indicate that CK improves glucose homeostasis by increasing L-cell numbers, which enhances GLP-1 release through a mechanism partially mediated by the gut microbiota-BA-TGR5 pathway. Therefore, that therapeutic attempts with CK might be useful for patients with T2DM.

• Food Science of Animal Resources
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• v.42 no.6
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• pp.1046-1060
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• 2022

This study aimed to investigate the effects of the metabolites of Latilactobacillus curvatus BYB3 and indole-activated aryl hydrocarbon receptor (AhR) to increase the tight junction (TJ) proteins in an in vitro model of intestinal inflammation. In a Western blot assay, the metabolites of L. curvatus BYB3 reduced the TJ demage in lipoploysaccharide (LPS) stimulated-Caco-2 cells. This reduction was a result of upregulating the expression of TJ-associated proteins and suppressing the nuclear factor-κB signaling. Immunofluorescence images consistently revealed that LPS disrupted and reduced the expression of TJ proteins, while the metabolites of L. curvatus BYB3 and indole reversed these alterations. The protective effects of L. curvatus BYB3 were observed on the intestinal barrier function when measuring transepithelial electrical resistance. Using high-performance liquid chromatography analysis the metabolites, the indole-3-latic acid and indole-3-acetamide concentrations were found to be 1.73±0.27 mg/L and 0.51±0.39 mg/L, respectively. These findings indicate that the metabolites of L. curvatus BYB3 have increasing mRNA expressions of cytochrome P450 1A1 (CYP1A1) and AhR, and may thus be applicable for therapy of various inflammatory gut diseases as postbiotics.

• The Korean Journal of Mycology
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• v.42 no.3
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• pp.191-200
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• 2014

Nuruk samples collected from various regions in Korea were investigated in terms of fungal contents and diversity. In measurement of colony forming unit (CFU) in Nuruk suspensions on DRBC agar, Nuruk samples MS4, MS8, and MS10 were among the highest fungal density, with $1,278.9{\pm}21.6$ (${\times}10^4$), $1,868.0{\pm}27.7$ (${\times}10^4$), and $775.1{\pm}19.2$ (${\times}10^4$) were among the samples showing the highest fungal density. CFU per 20 mg Nuruk, respectively. The majority of fungal components were yeasts, including Pichia anomala, P. kudriavzevii, Kluyveromyces marxianus, and Saccharomycopsis fibuligera, whereas Aspergillus oryzae and Rhizopus oryzae, the representative Nuruk fungi, were predominant only in the low fungal density Nuruks (MS2, MS5, and MS11). Saccharification capability of the fungal isolates was assessed by measurement of amylase activity in the culture broth. The highest amylase activity was found in A. niger and A. luchuensis, followed by S. fibuligera. A. oryzae and R. oryzae showed fair amylase activity but significantly lower than those of the three fungal species. R. oryzae was suggested to play an additional role in degradation of ${\beta}$-glucan in crop component of Nuruk since R. oryzae was the only fungus that showed ${\beta}$-glucanase activity among the fungal isolates. To confirm the safety of Nuruk, aflatoxigenicity of the isolated Aspergillus was estimated using the DNA markers norB-cypA, aflR, and omtA. All of the isolates turned out to be non-aflatoxigenic as evidenced by the deletion of gene markers, norB-cypA and aflR, and the absence of aflatoxin in the culture supernatants shown by TLC analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1695-1704
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• 2014

Maternal malnutrition during pregnancy may give rise to female offspring with disrupted ovary functions in adult age. Neonatal ovary development predisposes adult ovary function, yet the effect of maternal nutrition on the neonatal ovary has not been described. Therefore, here we show the impact of maternal protein restriction on the expression of folliculogenic and steroidogenic genes, their regulatory microRNAs and promoter DNA methylation in the ovary of neonatal piglets. Sows were fed either standard-protein (SP, 15% crude protein) or low-protein (LP, 7.5% crude protein) diets throughout gestation. Female piglets born to LP sows showed significantly decreased ovary weight relative to body weight (p<0.05) at birth, which was accompanied with an increased serum estradiol level (p<0.05). The LP piglets demonstrated higher ratio of bcl-2 associated X protein/B cell lymphoma/leukemia-2 mRNA (p<0.01), which was associated with up-regulated mRNA expression of bone morphogenic protein 4 (BMP4) (p<0.05) and proliferating cell nuclear antigen (PCNA) (p<0.05). The steroidogenic gene, cytochrome P450 aromatase (CYP19A1) was significantly down-regulated (p<0.05) in LP piglets. The alterations in ovarian gene expression were associated with a significant down-regulation of follicle-stimulating hormone receptor mRNA expression (p<0.05) in LP piglets. Moreover, three microRNAs, including miR-423-5p targeting both CYP19A1 and PCNA, miR-378 targeting CYP19A1 and miR-210 targeting BMP4, were significantly down-regulated (p<0.05) in the ovary of LP piglets. These results suggest that microRNAs are involved in mediating the effect of maternal protein restriction on ovarian function through regulating the expression of folliculogenic and steroidogenic genes in newborn piglets.

• Journal of Nutrition and Health
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• v.27 no.4
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• pp.347-355
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• 1994

Indolo[3,2-b]carbazole(ICZ) is a potent Ah receptor agonist with biological activities similar in several respects to those of the potent environmental toxin, TCDD. ICZ is produced during the oilgomerization of indole-3-carbinol(I3C), a breakdown product of the glucobrassicin present in food plants of the Brassica genus. In the present study we examined ICZ levels in tissues and excreta of rats treated with I3C or dietary cabbage of established glucobrasicin content, and in feces of conventional and germfree rats fed on a basal diet, and of humans. We also examined the levels of cytochrome P4501A1 induction, as determined by the ethoxyresorufin ο-deethylase assay, in tissues of animals that received cabbage-supplemented diets, or which were treated with purified I3C or ICZ. Our findings indicated that incorporation of either homogenized or whole freeze-dried cabbage in the feed led to large increases(16-60 fold) in the levels of ICZ in the feces and lower gastrointestinal tract of rats. We observed that whereas ICZ is readily detectable at about the same levels(2.00$\pm$0.50 ppb) in the feces of conventional rats fed on a purified diet and in human feces, levels of ICZ in the feces of germfree animals fed on the basal diet were at the limits of detection(0.40$\pm$0.20 ppb), indication that gut bacteria are important for the production of ICZ from essential dietary constituents in the basal diet. We showed that in contrast to the near 7000-fold difference in CYP1A1 inducing potencies of ICZ and TCDD in cells in culture, their inducing potencies differ by only about an order of magnitude in rats. Nonetheless, the levels of ICZ remaining in livers twenty hours after I3C treatment appear too low to account for the induced activity. This result indicates that ICZ may be rapidly cleared from the liver or that substances other than, or in addition to, ICZ be responsible for the enzyme-inducing activity of orally administered I3C or its precursors.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.708-719
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• 2007

Glutathione S-transferase genotypes GSTT1, GSTM1 and GSTP1 were characterized in 104 healthy male and female subjects and compared with parameters of oxidative stress at the level of DNA and lipids, with antioxidant enzymes, and with plasma antioxidants in smokers and non.smokers. Of the 104 subjects studied, 57.4% were GSTT1 present and 47.6% were GSTM1 present. The GSTP1 polymorphisms a and b were represented as follows: a/a, 75.5%; a/b, 21.6%; b/b type, 2.9%. The GSTT1 null genotype was associated with decreased glutathione in erythrocytes and elevated lymphocytes DNA damage. GST-Px was higher in GSTT1 null compared with GSTT1 present type. The homozygous GSTP1 genotype was not associated with any antioxidant status or DNA damage. The difference in plasma ${\alpha}$-carotene and erythrocytes GSH-Px and GST activities between smokers and non-smokers was detected in the GSTT1 null genotype. Plasma ${\gamma}$-tocopherol and ${\beta}$-carotene decreased significantly in smokers having GSTM1 null genotype. When GSTT1 and GSTM1 were combined, plasma lycopene and erythrocyte GST were reduced in smokers in both null types of these genes. As for GSTP1 genotype, plasma ${\alpha}$-carotene and erythrocytes GSH-Px decreased significantly in smokers with GSTP1 b/b, while erythrocytes GSH-Px activities decreased in smokers with GSTP1 a/b. The different ${\beta}$-carotene level between smokers and non-smokers was seen with both GSTP1 a/a and a/b genotype. It seems that polymorphisms in the phase II metabolizing enzyme glutathione S-transferase may be important determinants of commonly measured biomarkers.