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1.
Food Funct ; 14(21): 9606-9616, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37814601

ABSTRACT

The rising incidence of inflammatory bowel disease (IBD) has necessitated the search for safe and effective novel therapeutic strategies. Dietary flavonoids exhibited antioxidant, antiproliferative, and anticarcinogenic activities in several model systems with proven abilities to reduce inflammation and oxidative stress, thus they could be promising therapeutic agents for IBD prevention/treatment. However, understanding the role of a specific class of compounds in foods that promote health is difficult because of the chemically complex food matrices. This study aimed to utilize four maize near-isogenic lines to determine the anti-colitis effects of specific classes of flavonoids, anthocyanins and/or phlobaphenes, in a whole-food matrix. Results showed that the intake of anthocyanin and phlobaphene-enriched maize diets effectively alleviated dextran sodium sulfate (DSS)-induced colitis in mice via reducing the intestinal permeability and restoring the barrier function. Anthocyanin diets were more effective in maintaining the crypt structure and muc2 protein levels and reducing inflammation. Bacterial communities of mice consuming diets enriched with anthocyanins and phlobaphenes were more similar to the healthy control compared to the DSS control group, suggesting the role of flavonoids in modulating the gut microbiota to retrieve intestinal homeostasis. Microbiota depletion rendered these compounds ineffective against colitis. Lower serum concentrations of several phenolic acids were detected in the microbiota-depleted mice, indicating that gut microbiota plays a role in flavonoid metabolism and bioavailability.


Subject(s)
Colitis , Gastrointestinal Microbiome , Inflammatory Bowel Diseases , Animals , Mice , Anthocyanins/pharmacology , Zea mays , Dextrans , Health Promotion , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Inflammation , Inflammatory Bowel Diseases/chemically induced , Inflammatory Bowel Diseases/drug therapy , Flavonoids/adverse effects , Dextran Sulfate/adverse effects , Mice, Inbred C57BL , Disease Models, Animal , Colon/metabolism
2.
Mol Nutr Food Res ; 65(24): e2100152, 2021 12.
Article in English | MEDLINE | ID: mdl-34633750

ABSTRACT

SCOPE: Anthocyanin-containing potatoes exert anti-inflammatory activity in colitic mice. Gut bacterial dysbiosis plays a critical role in ulcerative colitis. This study examined the extent to which the anti-colitic activity of anthocyanin-containing red/purple-fleshed potatoes depends on the gut bacteria using a chemically-induced rodent model of colitis with the intact and antibiotic-ablated microbiome. METHODS AND RESULTS: Four-week-old male mice (C57BL6) are randomly assigned to the control diet or 20% purple-/red-fleshed potatoes supplemented diet group. The microbiota-ablated group received an antibiotic cocktail in drinking water. At week nine, colitis is induced by 2% dextran sulfate sodium (DSS) in drinking water for five days. Administration of antibiotics resulted in a 95% reduction in gut bacterial load and fecal SCFAs. DSS-induced elevated gut permeability and body weight loss are more pronounced in antibiotic mice compared to non-antibiotic mice. Purple- or red-fleshed potato supplementation (20% w/w) ameliorated DSS-induced reduction in colon length and mucin 2 expression levels, and increase in permeability, spleen weight, myeloperoxidase (MPO) activity, and inflammatory cytokines (IL-6, IL-17, and IL1-ß) expression levels in non-antibiotic mice, but not in gut microbiota ablated mice. CONCLUSIONS: Anthocyanin-containing potatoes are potent in alleviating colitis, and the gut microbiome is critical for the anti-colitic activity of anthocyanin-containing potatoes.


Subject(s)
Colitis , Gastrointestinal Microbiome , Solanum tuberosum , Animals , Anthocyanins/pharmacology , Colitis/chemically induced , Colitis/drug therapy , Colitis/metabolism , Colon/metabolism , Cytokines/metabolism , Dextran Sulfate/toxicity , Disease Models, Animal , Male , Mice , Mice, Inbred C57BL
3.
J Nutr Biochem ; 93: 108616, 2021 07.
Article in English | MEDLINE | ID: mdl-33705951

ABSTRACT

Ulcerative colitis (UC), a major form of inflammatory bowel disease (IBD), is on the rise worldwide. Approximately three million people suffer from IBD in the United States alone, but the current therapeutic options (e.g., corticosteroids) come with adverse side effects including reduced ability to fight infections. Thus, there is a critical need for developing effective, safe and evidence-based food products with anti-inflammatory activity. This study evaluated the antiinflammatory potential of purple-fleshed potato using a dextran sodium sulfate (DSS) murine model of colitis. Mice were randomly assigned to control (AIN-93G diet), P15 (15% purple-fleshed potato diet) and P25 (25% purple-fleshed potato diet) groups. Colitis was induced by 2% DSS administration in drinking water for six days. The results indicated that purple-fleshed potato supplementation suppressed the DSS-induced reduction in body weight and colon length as well as the increase in spleen and liver weights. P15 and P25 diets suppressed the elevation in the intestinal permeability, colonic MPO activity, mRNA expression and protein levels of pro-inflammatory interleukins IL-6 and IL-17, the relative abundance of specific pathogenic bacteria such as Enterobacteriaceae, Escherichia coli (E. coli) and pks+ E. coli, and the increased flagellin levels induced by DSS treatment. P25 alone suppressed the elevated systemic MPO levels in DSS-exposed mice, and elevated the relative abundance of Akkermansia muciniphila (A. muciniphila) as well as attenuated colonic mRNA expression level of IL-17 and the protein levels of IL-6 and IL-1ß. Therefore, the purple-fleshed potato has the potential to aid in the amelioration of UC symptoms.


Subject(s)
Anthocyanins/pharmacology , Colitis/chemically induced , Colitis/drug therapy , Dextran Sulfate/toxicity , Solanum tuberosum/chemistry , Animal Feed , Animals , Anthocyanins/chemistry , Bacteria/drug effects , Cytokines/genetics , Cytokines/metabolism , Diet , Gastrointestinal Microbiome/drug effects , Gene Expression Regulation/drug effects , Inflammation/drug therapy , Inflammation/metabolism , Mice , RNA, Messenger/genetics , RNA, Messenger/metabolism , Random Allocation , Solanum tuberosum/metabolism
4.
Mucosal Immunol ; 14(2): 420-430, 2021 03.
Article in English | MEDLINE | ID: mdl-32773769

ABSTRACT

In the intestine, IgA antibody-secreting B cells (IgA-ASCs) and helper T cells coordinate to maintain local homeostasis while their dysregulation could lead to development of intestinal inflammatory diseases. However, mechanisms underlying the coordinated localization and function of the B and T cells into the intestine, particularly the colon, are poorly understood. We herein report the first evidence that the gut-homing chemokine receptor CCR10+ IgA-ASCs form conjugates with helper T cells, preferentially regulatory T cells, at their differentiation sites of gut-associated lymphoid organs for their coordinated co-localization into the colon to promote local homeostasis. In CCR10-knockout mice, defective migration of IgA-ASCs also resulted in defective T-cell migration and homeostasis, and development of inflammatory symptoms in the colon. Antigen-specific interaction of CCR10+ IgA-ASCs and T cells is crucial for their homeostatic establishment in the colon. On the other hand, in IgA-knockout mice, preferential expansion of CCR10+ IgG1-ASCs with regulatory functions compensated for CCR10+ IgA-ASCs to help maintain colonic homeostasis. The preferential expansion of specific subclasses of CCR10+ IgG-ASCs with regulatory functions was also found in asymptomatic IgA-deficient patients. These findings suggest coordinated cell migration as a novel mechanism underlying localization and function of B and T cells in colonic homeostatic regulation.


Subject(s)
B-Lymphocytes/immunology , Colon/immunology , Receptors, CCR10/metabolism , T-Lymphocytes, Helper-Inducer/immunology , Adult , Aged , Aged, 80 and over , Animals , Antibody Formation , Cell Movement , Cells, Cultured , Female , Homeostasis , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Receptors, CCR10/genetics
5.
Growth Horm IGF Res ; 55: 101355, 2020 12.
Article in English | MEDLINE | ID: mdl-33032163

ABSTRACT

OBJECTIVE: The purpose of this study was to examine the influence of a novel "floatation-restricted environmental stimulation therapy" (floatation-REST) on growth hormone responses to an intense resistance exercise stress. DESIGN: Nine resistance trained men (age: 23.4 ±â€¯2.5 yrs.; height: 175.3 ±â€¯5.4 cm; body mass: 85.3 ±â€¯7.9 kg) completed a balanced, crossover-controlled study design with two identical exercise trials, differing only in post-exercise recovery intervention (i.e., control or floatation-REST). A two-week washout period was used between experimental conditions. Plasma lactate was measured pre-exercise, immediately post-exercise and after the 1 h. recovery interventions. Plasma iGH was measured pre-exercise, immediately-post exercise, and after the recovery intervention, as well as 24 h and 48 h after the exercise test. The bGH-L was measured only at pre-exercise and following each recovery intervention. RESULTS: For both experimental conditions, a significant (P ≤ 0.05) increase in lactate concentrations were observed immediately post-exercise (~14 mmol • L-1) and remained slightly elevated after the recovery condition. The same pattern of responses was observed for iGH with no differences from resting values at 24 and 48 h of recovery. The bGH-L showed no exercise-induced changes following recovery with either treatment condition, however concentration values were dramatically lower than ever reported. CONCLUSION: The use of floatation-REST therapy immediately following intense resistance exercise does not appear to influence anterior pituitary function in highly resistance trained men. However, the lower values of bGH suggest dramatically different molecular processing mechanisms at work in this highly trained population.


Subject(s)
Exercise , Human Growth Hormone/blood , Hydrocortisone/blood , Insulin-Like Growth Factor I/analysis , Lactic Acid/blood , Recovery of Function , Resistance Training , Adult , Biomarkers/blood , Case-Control Studies , Cross-Over Studies , Follow-Up Studies , Humans , Male , Prognosis , Sensory Deprivation , Young Adult
6.
Front Immunol ; 11: 559635, 2020.
Article in English | MEDLINE | ID: mdl-33117344

ABSTRACT

Vitamin A deficiency (A-) increases morbidity and mortality to gastrointestinal (GI) infection. Blocking retinoid signaling (dominant negative retinoic acid receptor, dnRAR) in intestinal epithelial cells (IEC, IECdnRAR) had no effect on vitamin A absorption, the expression of tight junction proteins or the integrity of the barrier. Immune cells in the gut were present in normal frequencies in the IECdnRAR mice, with the exception of the T cell receptor (TCR)αß+/CD8αα cells, which were significantly lower than in wildtype littermates. Challenging the IECdnRAR mice with dextran sodium sulfate to induce colitis or Citrobacter rodentium infection resulted in similar disease to wildtype littermates. Feeding mice vitamin A deficient diets reduced vitamin A status and the A- IECdnRAR mice developed more severe colitis and C. rodentium infection. In particular, retinoid signaling in the IEC was crucial for the A- host to survive early infection following C. rodentium. Treating A- mice with retinoic acid (RA) beginning on the day of infection protects most mice from early lethality. However, RA treatment of the A- IECdnRAR mice was ineffective for preventing lethality following C. rodentium infection. Retionid signaling in IEC is critical, especially when there are reduced levels of dietary vitamin A. IEC are direct targets of vitamin A for mounting early defense against infection.


Subject(s)
Colitis/metabolism , Colitis/mortality , Intestinal Mucosa/metabolism , Receptors, Retinoic Acid/metabolism , Retinoids/metabolism , Signal Transduction , Animals , Biomarkers , Citrobacter rodentium , Colitis/etiology , Colitis/pathology , Dextran Sulfate/adverse effects , Disease Models, Animal , Disease Susceptibility , Enterobacteriaceae Infections/etiology , Enterobacteriaceae Infections/metabolism , Enterobacteriaceae Infections/mortality , Enterobacteriaceae Infections/pathology , Intestinal Mucosa/microbiology , Mice , Mice, Knockout , Prognosis , Receptors, Retinoic Acid/genetics , Severity of Illness Index , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
7.
Metabolites ; 10(8)2020 Aug 11.
Article in English | MEDLINE | ID: mdl-32796650

ABSTRACT

Non-alcoholic steatohepatitis (NASH) represents the progressive sub-disease of non-alcoholic fatty liver disease that causes chronic liver injury initiated and sustained by steatosis and necroinflammation. The Ron receptor is a tyrosine kinase of the Met proto-oncogene family that potentially has a beneficial role in adipose and liver-specific inflammatory responses, as well as glucose and lipid metabolism. Since its discovery two decades ago, the Ron receptor has been extensively investigated for its differential roles on inflammation and cancer. Previously, we showed that Ron expression on tissue-resident macrophages limits inflammatory macrophage activation and promotes a repair phenotype, which can retard the progression of NASH in a diet-induced mouse model. However, the metabolic consequences of Ron activation have not previously been investigated. Here, we explored the effects of Ron receptor activation on major metabolic pathways that underlie the development and progression of NASH. Mice lacking apolipoprotein E (ApoE KO) and double knockout (DKO) mice that lack ApoE and Ron were maintained on a high-fat high-cholesterol diet for 18 weeks. We observed that, in DKO mice, the loss of ligand-dependent Ron signaling aggravated key pathological features in steatohepatitis, including steatosis, inflammation, oxidation stress, and hepatocyte damage. Transcriptional programs positively regulating fatty acid (FA) synthesis and uptake were upregulated in the absence of Ron receptor signaling, whereas lipid disposal pathways were downregulated. Consistent with the deregulation of lipid metabolism pathways, the DKO animals exhibited increased accumulation of FAs in the liver and decreased level of bile acids. Altogether, ligand-dependent Ron receptor activation provides protection from the deregulation of major metabolic pathways that initiate and aggravate non-alcoholic steatohepatitis.

8.
Growth Horm IGF Res ; 50: 9-22, 2020 02.
Article in English | MEDLINE | ID: mdl-31809882

ABSTRACT

OBJECTIVE: To revisit a finding, first described in 1978, which documented existence of a pituitary growth factor that escaped detection by immunoassay, but which was active in the established rat tibia GH bioassay. METHODS: We present a narrative review of the evolution of growth hormone complexity, and its bio-detectability, from a historical perspective. RESULTS: In humans under the age of 60, physical training (i.e. aerobic endurance and resistance training) are stressors which preferentially stimulate release of bioactive GH (bGH) into the blood. Neuroanatomical studies indicate a) that nerve fibers directly innervate the human anterior pituitary and b) that hind limb muscle afferents, in both humans and rats, also modulate plasma bGH. In the pituitary gland itself, molecular variants of GH, somatotroph heterogeneity and cell plasticity all appear to play a role in regulation of this growth factor. CONCLUSION: This review considers more recent findings on this often forgotten/neglected subject. Comparison testing of a) human plasma samples, b) sub-populations of separated rat pituitary somatotrophs or c) purified human pituitary peptides by GH bioassay vs immunoassay consistently yield conflicting results.


Subject(s)
Exercise/physiology , Human Growth Hormone/blood , Somatotrophs/metabolism , Afferent Pathways , Animals , Biological Assay/methods , Cell Plasticity , Endurance Training , Growth Hormone/blood , Growth Hormone/metabolism , Human Growth Hormone/metabolism , Humans , Hypothalamus/metabolism , Immunoassay/methods , Muscle, Skeletal/innervation , Physical Conditioning, Animal/physiology , Pituitary Gland, Anterior/innervation , Rats , Resistance Training , Somatotrophs/cytology
9.
J Forensic Sci ; 64(2): 446-453, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29758093

ABSTRACT

The abundance of, and reliance upon, human electro-muscular incapacitation (HEMI) devices, especially in law enforcement, has generated scrutiny and examination of these technologies. The purpose of this study was to examine cardiovascular effects resulting from typical (5 sec) and longer activation (20 sec) HEMI applications studying myocardial function and peripheral vascular system using a combination of invasive cardiovascular catheters and transesophageal echocardiography (TEE). Six healthy swine (Sus scrofa) 3-5 months in age and weighing between 60 and 86 kg were anesthetized and exposed to the TASER Model X26 waveform while transesophageal echocardiography was performed. Stroke volume was shown to statistically decrease during HEMI application indicating an increase in systemic vascular resistance, but HEMI application did not result in myocardial dysfunction ("cardiac stunning").


Subject(s)
Echocardiography, Transesophageal , Electric Stimulation/instrumentation , Stroke Volume , Vascular Resistance , Weapons , Animals , Blood Pressure , Blood Volume , Carbon Dioxide/blood , Cardiac Catheterization , Catheters, Indwelling , Central Venous Pressure , Forensic Medicine , Hematocrit , Hemoglobins/analysis , Humans , Hydrogen-Ion Concentration , Lactic Acid/blood , Models, Animal , Muscle Contraction , Potassium/blood , Sodium/blood , Swine
10.
Cell ; 175(3): 679-694.e22, 2018 10 18.
Article in English | MEDLINE | ID: mdl-30340040

ABSTRACT

Dietary soluble fibers are fermented by gut bacteria into short-chain fatty acids (SCFA), which are considered broadly health-promoting. Accordingly, consumption of such fibers ameliorates metabolic syndrome. However, incorporating soluble fiber inulin, but not insoluble fiber, into a compositionally defined diet, induced icteric hepatocellular carcinoma (HCC). Such HCC was microbiota-dependent and observed in multiple strains of dysbiotic mice but not in germ-free nor antibiotics-treated mice. Furthermore, consumption of an inulin-enriched high-fat diet induced both dysbiosis and HCC in wild-type (WT) mice. Inulin-induced HCC progressed via early onset of cholestasis, hepatocyte death, followed by neutrophilic inflammation in liver. Pharmacologic inhibition of fermentation or depletion of fermenting bacteria markedly reduced intestinal SCFA and prevented HCC. Intervening with cholestyramine to prevent reabsorption of bile acids also conferred protection against such HCC. Thus, its benefits notwithstanding, enrichment of foods with fermentable fiber should be approached with great caution as it may increase risk of HCC.


Subject(s)
Carcinoma, Hepatocellular/etiology , Cholestasis/complications , Dietary Fiber/metabolism , Dysbiosis/complications , Fermentation , Gastrointestinal Microbiome , Liver Neoplasms/etiology , Animals , Carcinoma, Hepatocellular/microbiology , Cell Line, Tumor , Cholestasis/microbiology , Diet, High-Fat/adverse effects , Dysbiosis/microbiology , Inulin/adverse effects , Liver Neoplasms/microbiology , Male , Mice , Mice, Inbred C57BL
11.
J Proteome Res ; 17(9): 3268-3280, 2018 09 07.
Article in English | MEDLINE | ID: mdl-30091925

ABSTRACT

Liver fibrosis is commonly observed in the terminal stages of nonalcoholic steatohepatitis (NASH) and with no specific and effective antifibrotic therapies available, this disease is a major global health burden. The MSP/Ron receptor axis has been shown to have anti-inflammatory properties in a number of mouse models, due at least in part, to its ability to limit pro-inflammatory responses in tissue-resident macrophages and hepatocytes. In this study, we established the role of the Ron receptor in steatohepatitis-induced hepatic fibrosis using Ron ligand domain knockout mice on an apolipoprotein E knockout background (DKO). After 18 weeks of high-fat high-cholesterol feeding, loss of Ron activation resulted in exacerbated NASH-associated steatosis which is precedent to hepatocellular injury, inflammation and fibrosis. 1H nuclear magnetic resonance (NMR)-based metabolomics identified significant changes in serum metabolites that can modulate the intrahepatic lipid pool in hepatic steatosis. Serum from DKO mice had higher concentrations of lipids, VLDL/LDL and pyruvate, whereas glycine levels were reduced. Parallel to the aggravated steatohepatitis, increased accumulation of collagen, inflammatory immune cells and collagen producing-myofibroblasts were seen in the livers of DKO mice. Gene expression profiling revealed that DKO mice exhibited elevated expression of genes encoding Ron receptor ligand MSP, collagens, ECM remodeling proteins and pro-fibrogenic cytokines in the liver. Our results demonstrate the protective effects of Ron receptor activation on NASH-induced hepatic fibrosis.


Subject(s)
Liver Cirrhosis/metabolism , Liver/metabolism , Non-alcoholic Fatty Liver Disease/metabolism , Receptor Protein-Tyrosine Kinases/genetics , Signal Transduction , Animals , Apolipoproteins E/deficiency , Apolipoproteins E/genetics , Cholesterol/administration & dosage , Cholesterol, LDL/blood , Cholesterol, VLDL/blood , Collagen/genetics , Collagen/metabolism , Cytokines/genetics , Cytokines/metabolism , Diet, High-Fat/methods , Disease Models, Animal , Extracellular Matrix Proteins/genetics , Extracellular Matrix Proteins/metabolism , Gene Expression Profiling , Gene Expression Regulation , Glycine/blood , Humans , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/genetics , Liver Cirrhosis/pathology , Male , Mice , Mice, Knockout , Myofibroblasts/metabolism , Myofibroblasts/pathology , Non-alcoholic Fatty Liver Disease/complications , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/pathology , Pyruvic Acid/blood , Receptor Protein-Tyrosine Kinases/deficiency
12.
Blood ; 131(23): 2568-2580, 2018 06 07.
Article in English | MEDLINE | ID: mdl-29615406

ABSTRACT

Micronutrient selenium (Se) plays a key role in redox regulation through its incorporation into selenoproteins as the 21st amino acid selenocysteine (Sec). Because Se deficiency appears to be a cofactor in the anemia associated with chronic inflammatory diseases, we reasoned that selenoproteins may contribute to erythropoietic recovery from anemia, referred to as stress erythropoiesis. Here, we report that loss of selenoproteins through Se deficiency or by mutation of the Sec tRNA (tRNA[Sec]) gene (Trsp) severely impairs stress erythropoiesis at 2 stages. Early stress erythroid progenitors failed to expand and properly differentiate into burst-forming unit-erythroid cells , whereas late-stage erythroid progenitors exhibited a maturation defect that affected the transition of proerythroblasts to basophilic erythroblasts. These defects were, in part, a result of the loss of selenoprotein W (SelenoW), whose expression was reduced at both transcript and protein levels in Se-deficient erythroblasts. Mutation of SelenoW in the bone marrow cells significantly decreased the expansion of stress burst-forming unit-erythroid cell colonies, which recapitulated the phenotypes induced by Se deficiency or mutation of Trsp Similarly, mutation of SelenoW in murine erythroblast (G1E) cell line led to defects in terminal differentiation. In addition to the erythroid defects, the spleens of Se-deficient mice contained fewer red pulp macrophages and exhibited impaired development of erythroblastic island macrophages, which make up the niche supporting erythroblast development. Taken together, these data reveal a critical role of selenoproteins in the expansion and development of stress erythroid progenitors, as well as the erythroid niche during acute anemia recovery.


Subject(s)
Anemia/metabolism , Erythroid Precursor Cells/cytology , Erythropoiesis , Selenium/deficiency , Selenoproteins/metabolism , Anemia/genetics , Animals , Down-Regulation , Erythroblasts/cytology , Erythroblasts/metabolism , Erythroid Precursor Cells/metabolism , Mice, Inbred C57BL , Mutation , Selenium/metabolism , Selenoprotein W/genetics , Selenoprotein W/metabolism , Selenoproteins/genetics , Spleen/cytology , Spleen/metabolism
13.
Front Immunol ; 9: 408, 2018.
Article in English | MEDLINE | ID: mdl-29599772

ABSTRACT

To determine the effect of the microbiota on vitamin D metabolism, serum 25-hydroxyvitamin D(25D), 24,25-dihydroxyvitamin D (24,25D), and 1,25-dihydroxyvitamin D (1,25D) were measured in germ-free (GF) mice before and after conventionalization (CN). GF mice had low levels of 25D, 24,25D, and 1,25D and were hypocalcemic. CN of the GF mice with microbiota, for 2 weeks recovered 25D, 24,25D, and 1,25D levels. Females had more 25D and 24,25D than males both as GF mice and after CN. Introducing a limited number of commensals (eight commensals) increased 25D and 24,25D to the same extent as CN. Monocolonization with the enteric pathogen Citrobacter rodentium increased 25D and 24,25D, but the values only increased after 4 weeks of C. rodentium colonization when inflammation resolved. Fibroblast growth factor (FGF) 23 was extremely high in GF mice. CN resulted in an increase in TNF-α expression in the colon 2 days after CN that coincided with a reduction in FGF23 by 3 days that eventually normalized 25D, 24,25D, 1,25D at 1-week post-CN and reinstated calcium homeostasis. Neutralization of FGF23 in GF mice raised 1,25D, without CN, demonstrating that the high FGF23 levels were responsible for the low calcium and 1,25D in GF mice. The microbiota induce inflammation in the GF mice that inhibits FGF23 to eventually reinstate homeostasis that includes increased 25D, 24,25D, and 1,25D levels. The microbiota through FGF23 regulates vitamin D metabolism.


Subject(s)
Citrobacter rodentium/physiology , Colon/immunology , Endocrine System/metabolism , Fibroblast Growth Factors/blood , Gastrointestinal Microbiome/physiology , Vitamin D/metabolism , Animals , Colon/microbiology , Female , Fibroblast Growth Factor-23 , Germ-Free Life , Male , Mice , Mice, Inbred C57BL , Sex Factors , Tumor Necrosis Factor-alpha/metabolism , Vitamin D/analogs & derivatives , Vitamin D/blood
14.
J Nutr Biochem ; 56: 65-73, 2018 06.
Article in English | MEDLINE | ID: mdl-29459310

ABSTRACT

Vitamin D, 25hydroxyvitamin D (25D), and 24,25dihydroxyvitamin D (24,25D) were measured before and after broad spectrum antibiotic (Abx) treatment for 2 wks. Abx treatments increased 25D and 24,25D levels suggesting that the microbiota or Abx were altering vitamin D metabolism. Increased 25D, but not 24,25D, following Abx treatments were found to be dependent on toll like receptor signaling. Conversely, the effects of Abx on 24,25D levels required that the vitamin D receptor (VDR) be expressed in tissues outside of the hematopoietic system (kidney) and not the immune system. Fibroblast growth factor (FGF)23 increased following Abx treatment and the effect of Abx treatment on FGF23 (like the effect on 24,25D) was not present in VDR knockout (KO) mice. The Abx mediated increase in 24,25D was due to changes to the endocrine regulation of vitamin D metabolism. Conversely, 25D levels went up with Abx treatment of the VDR KO mice. Host sensing of microbial signals regulates the levels of 25D in the host.


Subject(s)
Anti-Bacterial Agents/pharmacology , Fibroblast Growth Factors/metabolism , Gene Expression Regulation , Microbiota , Vitamin D/metabolism , 24,25-Dihydroxyvitamin D 3/metabolism , 25-Hydroxyvitamin D3 1-alpha-Hydroxylase/genetics , Ampicillin/administration & dosage , Animals , Female , Fibroblast Growth Factor-23 , Ligands , Male , Metronidazole/administration & dosage , Mice , Mice, Inbred C57BL , Mice, Knockout , Neomycin/administration & dosage , Receptors, Calcitriol/metabolism , Signal Transduction , Toll-Like Receptors/metabolism , Vancomycin/administration & dosage , Vitamin D/analogs & derivatives
15.
Food Chem Toxicol ; 111: 302-309, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29175576

ABSTRACT

Green tea and (-)-epigallocatechin-3-gallate (EGCG) have been studied for their obesity-related health effects. Many green tea extract (GTE)-based dietary supplements are commercially-available. Although green tea beverage has a long history of safe use, a growing number of case-reports have linked GTE-based supplements to incidents of hepatotoxicity. Animal studies support the hepatotoxic potential of GTE and EGCG, but the mechanisms remain unclear. Here, we examined the hepatotoxic effects of EGCG in C57BL/6J mice and evaluated changes in hepatic antioxidant response and mitochondria structure and function. Intragastric dosing with EGCG (500 - 750 mg/kg) once daily for 3 d caused hepatic inflammation, necrosis, and hemorrhage. Hepatotoxicity was associated with increased oxidative stress and decreased superoxide dismutase and glutathione peroxidase levels. Real-time PCR and transmission electron microscopy showed decreased hepatic mitochondria copy number in EGCG-treated mice. The mRNA levels of marker genes of respiratory complex I and III, sirtuin 3, forkhead box O3a, and peroxisome-EGCG-treated mice. Sirtuin 3 protein levels were also decreased by EGCG. Our data indicate the mitochondria may be a target for EGCG, and that inhibition of mitochondria function/antioxidant response may be important for the hepatotoxicity of bolus EGCG.


Subject(s)
Catechin/analogs & derivatives , Chemical and Drug Induced Liver Injury/metabolism , Mitochondria, Liver/drug effects , Oxidative Stress/drug effects , Tea/chemistry , Animals , Antioxidants/metabolism , Biomarkers , Catechin/pharmacology , DNA Damage/drug effects , Electron Transport Chain Complex Proteins/genetics , Electron Transport Chain Complex Proteins/metabolism , Gene Expression Regulation/drug effects , Glutathione/metabolism , Lipid Peroxidation/drug effects , Liver/enzymology , Male , Mice , Mice, Inbred C57BL , Mitochondria, Liver/metabolism
16.
Front Immunol ; 9: 3090, 2018.
Article in English | MEDLINE | ID: mdl-30671060

ABSTRACT

Vitamin A deficiency affects over 250 million preschool-age children worldwide and is associated with increased childhood mortality and risk of developing enteric infections. Vitamin A deficient (A-) mice developed chronic Citrobacter rodentium infection. A single oral dose of retinoic acid (RA) at d7 post-infection was sufficient to induce clearance of the pathogen in A- mice. RA treatment of A- mice induced il17 expression in the colon. In A- mice, colonic IL-17 was primarily produced by CD11b+ cells; however, in A+ mice, the major source of colonic IL-17 was CD4+ T cells. To determine the cellular targets of vitamin A required for host resistance to C. rodentium, mice that express a dominant negative (dn) retinoic acid receptor (RAR) in T cells (T-dnRAR) or macrophage/neutrophils (LysM-dnRAR) were used. T-dnRAR mice had T cells that produced a robust intestinal IL-17 response and for 40% of the mice was enough to clear the infection. The remainder of the T-dnRAR mice developed a chronic infection. A- LysM-dnRAR mice developed early lethal infections with surviving mice becoming chronically infected. RA treatment of A- LysM-dnRAR mice was ineffective for inducing colonic IL-17 or clearing C. rodentium. Retinoid signaling is required in T cells and CD11b+ cells for complete elimination of enteric pathogens.


Subject(s)
CD11b Antigen/metabolism , Citrobacter rodentium/drug effects , Enterobacteriaceae Infections/drug therapy , T-Lymphocytes/metabolism , Tretinoin/therapeutic use , Vitamin A Deficiency/drug therapy , Analysis of Variance , Animals , Citrobacter rodentium/metabolism , Colon/immunology , Enterobacteriaceae Infections/etiology , Interleukin-17/metabolism , Liver/immunology , Liver/metabolism , Mice , Mice, Inbred C57BL , Tretinoin/metabolism , Vitamin A Deficiency/chemically induced , Vitamin A Deficiency/complications
17.
J Funct Foods ; 37: 685-698, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29242716

ABSTRACT

Consumption of broccoli mediates numerous chemo-protective benefits through the intake of phytochemicals, some of which modulate aryl hydrocarbon receptor (AHR) activity. Whether AHR activation is a critical aspect of the therapeutic potential of dietary broccoli is not known. Here we administered isocaloric diets, with or without supplementation of whole broccoli (15% w/w), to congenic mice expressing the high-affinity Ahrb/b or low-affinity Ahrd/d alleles, for 24 days and examined the effects on AHR activity, intestinal microbial community structure, inflammatory status, and response to chemically induced colitis. Cecal microbial community structure and metabolic potential were segregated according to host dietary and AHR status. Dietary broccoli associated with heightened intestinal AHR activity, decreased microbial abundance of the family Erysipelotrichaceae, and attenuation of colitis. In summary, broccoli consumption elicited an enhanced response in ligand-sensitive Ahrb/b mice, demonstrating that in part the beneficial aspects of dietary broccoli upon intestinal health are associated with heightened AHR activity.

18.
mSystems ; 2(5)2017.
Article in English | MEDLINE | ID: mdl-29034330

ABSTRACT

Bisphenol A (BPA) accumulates in the maturing gut and liver in utero and is known to alter gut bacterial profiles in offspring. Gut bacterial dysbiosis may contribute to chronic colonic and systemic inflammation. We hypothesized that perinatal BPA exposure-induced intestinal (and liver) inflammation in offspring is due to alterations in the microbiome and colonic metabolome. The 16S rRNA amplicon sequencing analysis revealed differences in beta diversity with a significant reduction in the relative abundances of short-chain fatty acid (SCFA) producers such as Oscillospira and Ruminococcaceae due to BPA exposure. Furthermore, BPA exposure reduced fecal SCFA levels and increased systemic lipopolysaccharide (LPS) levels. BPA exposure-increased intestinal permeability was ameliorated by the addition of SCFA in vitro. Metabolic fingerprints revealed alterations in global metabolism and amino acid metabolism. Thus, our findings indicate that perinatal BPA exposure may cause gut bacterial dysbiosis and altered metabolite profiles, particularly SCFA profiles, leading to chronic colon and liver inflammation. IMPORTANCE Emerging evidence suggests that environmental toxicants may influence inflammation-promoted chronic disease susceptibility during early life. BPA, an environmental endocrine disruptor, can transfer across the placenta and accumulate in fetal gut and liver. However, underlying mechanisms for BPA-induced colonic and liver inflammation are not fully elucidated. In this report, we show how perinatal BPA exposure in rabbits alters gut microbiota and their metabolite profiles, which leads to colonic and liver inflammation as well as to increased gut permeability as measured by elevated serum lipopolysaccharide (LPS) levels in the offspring. Also, perinatal BPA exposure leads to reduced levels of gut bacterial diversity and bacterial metabolites (short-chain fatty acids [SCFA]) and elevated gut permeability-three common early biomarkers of inflammation-promoted chronic diseases. In addition, we showed that SCFA ameliorated BPA-induced intestinal permeability in vitro. Thus, our study results suggest that correcting environmental toxicant-induced bacterial dysbiosis early in life may reduce the risk of chronic diseases later in life.

19.
Proc Natl Acad Sci U S A ; 114(35): 9397-9402, 2017 08 29.
Article in English | MEDLINE | ID: mdl-28808019

ABSTRACT

In host-pathogen arms races, increases in host resistance prompt counteradaptation by pathogens, but the nature of that counteradaptation is seldom directly observed outside of laboratory models. The best-documented field example is the coevolution of myxoma virus (MYXV) in European rabbits. To understand how MYXV in Australia has continued to evolve in wild rabbits under intense selection for genetic resistance to myxomatosis, we compared the phenotypes of the progenitor MYXV and viral isolates from the 1950s and the 1990s in laboratory rabbits with no resistance. Strikingly, and unlike their 1950s counterparts, most virus isolates from the 1990s induced a highly lethal immune collapse syndrome similar to septic shock. Thus, the next step in this canonical case of coevolution after a species jump has been further escalation by the virus in the face of widespread host resistance.


Subject(s)
Myxoma virus/genetics , Poxviridae Infections/veterinary , Rabbits/virology , Tumor Virus Infections/veterinary , Animals , Australia/epidemiology , Biological Evolution , Myxoma virus/pathogenicity , Poxviridae Infections/epidemiology , Poxviridae Infections/pathology , Time Factors , Tumor Virus Infections/epidemiology , Tumor Virus Infections/pathology , Virulence
20.
Growth Horm IGF Res ; 34: 45-54, 2017 06.
Article in English | MEDLINE | ID: mdl-28551577

ABSTRACT

OBJECTIVE: The consequences of age-related decline in the somatotropic axis of humans are complex and remain largely unresolved. We tested the hypothesis that hGH measurements of plasma by bioassay vs immunoassay from samples obtained from free-living, elderly individuals would reveal a dichotomy in GH activities that are correlated with the functional status of the donors, i.e. their healthspan. DESIGN: Forty-one men and women of advanced age (men: N=16, age, 80.5±6.5years; height, 173.1±6.9cm; body mass, 81.8±13.0kg) and (women: N=25, age, 80.7±7.2years; height, 157.7±6.0cm; body mass, 68.8±17kg), were recruited for a cross-sectional study. Participants filled out PROMIS (Patient-Reported Outcomes Measurement Information System, U. S. Department of Health and Human Services) scales, undertook physical performance tests and had fasted blood samples obtained at rest for measurement of hormonal and immunology biomarkers. RESULTS: When measured by the well-established rat tibial line GH bioassay, one half of the plasma samples (n=20) contained bioassayable GH (bGH), but the other half (n=21) failed to mount increases in tibial plate width above saline injected controls. This difference did not correlate with the age, sex or physical functionality of the plasma donor. It also did not correlate with hGH concentrations measured by immunoassay. In those cases in which bGH was detected, various hierarchical regression models predicted that GHRH, c-peptide, VEGF, NPY, IL-4 and T-regulatory lymphocytes were associated with the difference and predicted bGH. CONCLUSION: Results from this study suggest that the actions of bGH at the cellular level may be modified by other factors and that this may explain the lack of correlations observed in this study.


Subject(s)
Aging/blood , Aging/immunology , Biomarkers/blood , Human Growth Hormone/blood , Longevity , Age Factors , Aged , Aged, 80 and over , Body Height , Cross-Sectional Studies , Female , Humans , Longevity/immunology , Male
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