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7
result(s) for
"Turgeon, Danielle Kim"
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A multi-mineral intervention to improve disease-related and mechanistic biomarkers in ulcerative colitis patients: Results from a randomized trial
by
Aslam, Muhammad N
,
Moraga, Gillian
,
Varani, James
in
Adjuvants, Pharmaceutic
,
Adult
,
Alkaline phosphatase
2025
The long-term goal of our ongoing studies is to determine if, and to what extent, a multi-mineral product (Aquamin) could benefit individuals with ulcerative colitis (UC). As a step toward achieving that goal, we carried out a pilot 180-day biomarker trial (clinicaltrials.gov ID: NCT03869905) in patients with UC in remission or with mild disease.
A total of 28 subjects participated in the study. Each subject was randomly assigned to receive either Aquamin for 180 days or placebo for 90 days. At Day-90, placebo subjects crossed over to Aquamin for the final 90 days. At Day-0, -90 and -180, serum samples were analyzed for C-reactive protein (CRP), alkaline phosphatase (ALP), intestine-specific ALP (ALPI), and for biomarkers of bone turnover (osteocalcin, TRAP5b and bone-specific ALP [BALP]). Stool specimens were assessed for fecal calprotectin (fCAL) and colon biopsies were examined histologically by Geboes scoring at the same time points. Each subject underwent DEXA scanning (at Day-0 and Day-180 only). In addition, mass spectrometry-based proteomic assessment was performed using colon biopsies obtained at each time point.
Subjects who received Aquamin for the complete 180-day period (a total of 12) demonstrated improvements in all biomarkers (CRP, fCAL, ALP, ALPI, and Geboes scoring); this was not observed in the placebo group (16 subjects). When cumulative pre-post differences were compared between the Aquamin and placebo groups, Aquamin treatment significantly decreased these differences (a 24% decrease as compared to a 38% increase with placebo, p = 0.0284). Subjects who received Aquamin for 90-days showed intermediary responses. Subjects receiving Aquamin for 180 days also demonstrated increases in bone mineral density (BMD) and bone mineral content (BMC), resulting in a statistically significant increase (7.3%, p = 0.0324) in the hip strength index over the treatment period. This was accompanied by increases in osteocalcin and TRAP5b and a decrease in BALP. The proteomic screen demonstrated upregulation of multiple gut barrier proteins, cell surface transporter molecules and certain proteins with anti-inflammatory potential in response to Aquamin. Aquamin treatment also led to downregulation of several proteins associated with the pro-inflammatory state.
The results presented here suggest that the use of a multi-mineral intervention improves disease-related biomarkers in patients with UC. These studies suggest the potential value of the mineral intervention as a low-cost, non-toxic adjuvant therapy for mild UC or for individuals with UC in remission.
Journal Article
Calcium-induced differentiation in normal human colonoid cultures: Cell-cell / cell-matrix adhesion, barrier formation and tissue integrity
by
Attili, Durga
,
Nadeem, Daniyal M.
,
Rizvi, Areeba H.
in
Adenoma - metabolism
,
Adenoma - pathology
,
Adhesion
2019
The goal of the study was to assess calcium alone and Aquamin, a multi-mineral natural product that contains magnesium and detectable levels of 72 trace elements in addition to calcium, for capacity to affect growth and differentiation in colonoid cultures derived from histologically-normal human colon tissue.
Colonoid cultures were maintained in a low-calcium (0.25 mM) medium or in medium supplemented with an amount of calcium (1.5-3.0 mM), either from calcium alone or Aquamin for a period of two weeks. This was shown in a previous study to induce differentiation in colonoids derived from large adenomas. Changes in growth, morphological features and protein expression profile were assessed at the end of the incubation period using a combination of phase-contrast and scanning electron microscopy, histology and immunohistology, proteomic assessment and transmission electron microscopy.
Unlike the previously-studied tumor-derived colonoids (which remained un-differentiated in the absence of calcium-supplementation), normal tissue colonoids underwent differentiation as indicated by gross and microscopic appearance, a low proliferative index and high-level expression of cytokeratin 20 in the absence of intervention (i.e., in control condition). Only modest additional changes were seen in these parameters with either calcium alone or Aquamin (providing up to 3.0 mM calcium). In spite of this, proteomic analysis and immunohistochemistry revealed that both interventions induced strong up-regulation of proteins that promote cell-cell and cell-matrix adhesive functions, barrier formation and tissue integrity. Transmission electron microscopy revealed an increase in desmosomes in response to intervention.
These findings demonstrate that colonoids derived from histologically normal human tissue can undergo differentiation in the presence of a low ambient calcium concentration. However, higher calcium levels induce elaboration of proteins that promote cell-cell and cell-matrix adhesion. These changes could lead to improved barrier function and improved colon tissue health.
Journal Article
Ulcerative Colitis-Derived Colonoid Culture: A Multi-Mineral-Approach to Improve Barrier Protein Expression
by
Attili, Durga
,
Nadeem, Daniyal M.
,
Rizvi, Areeba H.
in
Algae
,
basement membrane
,
Basement membranes
2020
Recent studies demonstrated that Aquamin
, a calcium-, magnesium-rich, multi-mineral natural product, improves barrier structure and function in colonoids obtained from the tissue of healthy subjects. The goal of the present study was to determine if the colonic barrier could be improved in tissue from subjects with ulcerative colitis (UC).
Colonoid cultures were established with colon biopsies from 9 individuals with UC. The colonoids were then incubated for a 2-week period under control conditions (in culture medium with a final calcium concentration of 0.25 mM) or in the same medium supplemented with Aquamin
to provide 1.5 - 4.5 mM calcium. Effects on differentiation and barrier protein expression were determined using several approaches: phase-contrast and scanning electron microscopy, quantitative histology and immunohistology, mass spectrometry-based proteome assessment and transmission electron microscopy.
Although there were no gross changes in colonoid appearance, there was an increase in lumen diameter and wall thickness on histology and greater expression of cytokeratin 20 (CK20) along with reduced expression of Ki67 by quantitative immunohistology observed with intervention. In parallel, upregulation of several differentiation-related proteins was seen in a proteomic screen with the intervention. Aquamin
-treated colonoids demonstrated a modest up-regulation of tight junctional proteins but stronger induction of adherens junction and desmosomal proteins. Increased desmosomes were seen at the ultrastructural level. Proteomic analysis demonstrated increased expression of several basement membrane proteins and hemidesmosomal components. Proteins expressed at the apical surface (mucins and trefoils) were also increased as were several additional proteins with anti-microbial activity or that modulate inflammation. Finally, several transporter proteins that affect electrolyte balance (and, thereby affect water resorption) were increased. At the same time, growth and cell cycle regulatory proteins (Ki67, nucleophosmin, and stathmin) were significantly down-regulated. Laminin interactions, matrix formation and extracellular matrix organization were the top three up-regulated pathways with the intervention.
A majority of individuals including patients with UC do not reach the recommended daily intake for calcium and other minerals. To the extent that such deficiencies might contribute to the weakening of the colonic barrier, the findings employing UC tissue-derived colonoids here suggest that adequate mineral intake might improve the colonic barrier.
Journal Article
In vitro models of the human esophagus reveal ancestrally diverse response to injury
by
Wu, Angeline
,
Higgins, Peter Dr
,
Karpoff, Kateryna
in
Adenocarcinoma
,
Cell Biology
,
Cell culture
2021
European Americans (EA) are more susceptible to esophageal tissue damage and inflammation when exposed to gastric acid and bile acid reflux and have a higher incidence of esophageal adenocarcinoma when compared to African Americans (AA). Population studies have implicated specific genes for these differences; however, the underlying cause for these differences is not well understood. We describe a robust long-term culture system to grow primary human esophagus in vitro, use single cell RNA sequencing to compare primary human biopsies to their in vitro counterparts, identify known and new molecular markers of basal cell types, and demonstrate that in vivo cellular heterogeneity is maintained in vitro. We further developed an ancestrally diverse biobank and a high-content, image based, screening assay to interrogate bile-acid injury response. These results demonstrated that AA esophageal cells responded significantly differently than EA-derived cells, mirroring clinical findings, having important implications for addressing disparities in early drug development pipelines. Competing Interest Statement The authors have declared no competing interest.
Spatial variation of the native colon microbiota in healthy adults
by
Danielle Kim Turgeon
,
Schloss, Patrick D
,
Flynn, Kaitlin J
in
Abundance
,
Classification
,
Colon
2018
The microbiome has been implicated in the development of colorectal cancer (CRC) and inflammatory bowel diseases (IBD). The specific traits of these diseases vary along the axis of the digestive tract. Further, variation in the structure of the gut microbiota has been associated with both diseases. Here we profiled the microbiota of the healthy proximal and distal mucosa and lumen to better understand how bacterial populations vary along the colon. We used a two-colonoscope approach to sample proximal and distal mucosal and luminal contents from the colons of 20 healthy subjects that had not undergone any bowel preparation procedure. The biopsies and home-collected stool were subjected to 16S rRNA gene sequencing and Random Forest classification models were built using taxa abundance and location to identify microbiota specific to each site. The right mucosa and lumen had the most similar community structures of the five sites we considered from each subject. The distal mucosa had higher relative abundance of Finegoldia, Murdochiella, Peptoniphilus, Porphyromonas and Anaerococcus. The proximal mucosa had more of the genera Enterobacteriaceae, Bacteroides and Pseudomonas. The classification model performed well when classifying mucosal samples into proximal or distal sides (AUC = 0.808). Separating proximal and distal luminal samples proved more challenging (AUC = 0.599) and specific microbiota that differentiated the two were hard to identify. By sampling the unprepped colon, we identified distinct bacterial populations native to the proximal and distal sides. Further investigation of these bacteria may elucidate if and how these groups contribute to different disease processes on their respective sides of the colon.
Effect of ginger root on cyclooxygenase-1 and 15-hydroxyprostaglandin dehydrogenase expression in colonic mucosa of humans at normal and increased risk for colorectal cancer
by
Wright, Benjamin D.
,
Brenner, Dean E.
,
Ruffin, Mack T.
in
Adult
,
Biological and medical sciences
,
Carcinoma in Situ - genetics
2013
Elevated tissue levels of prostaglandin E₂, produced by cyclooxygenase (COX), are an early event in colorectal cancer (CRC). Data suggest the efficacy of nonsteroidal anti-inflammatory drugs, such as cancer preventives, in the inhibition of COX activity; however, side effects of nonsteroidal anti-inflammatory pose unacceptable limitations. Ginger has been reported to have anti-inflammatory activities with significant CRC preventive potential. We investigated whether consumption of 2.0 g ginger daily regulated the level of two key enzymes that control prostaglandin E₂ production, COX-1 and NAD⁺-dependent 15-hydroxyprostaglandin dehydrogenase (15-PGDH). Thirty participants at normal and 20 participants at increased risk for CRC were randomized and given 2.0 g/day ginger or placebo for 28 days. Flexible sigmoidoscopy was used to obtain colon biopsies at baseline and the end of the study. Tissue levels of COX-1 and 15-PGDH were assessed using western blotting. After ginger consumption, participants at increased risk for CRC had a significantly reduced colonic COX-1 protein level (23.8±41%) compared with the placebo group (18.9±52%; P=0.03). Protein levels of 15-PGDH in the colon were unchanged. In participants who were at normal risk for CRC, neither protein levels of COX-1 nor 15-PGDH in the colon were altered by ginger consumption. Ginger significantly lowered COX-1 protein expression in participants at increased risk for CRC but not in those at normal risk for CRC. Ginger did not alter 15-PGDH protein expression in either increased or normal-risk participants. Further investigation, in larger studies with a longer ginger intervention, is needed to examine the ability of ginger to impact tissue levels of prostaglandin.
Journal Article