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Nadeem, D. M.

Publications and source records attributed to Nadeem, D. M..

2 recordsLinked to original sources

Red Algae-Derived Mineral Intervention to Counter Pro-inflammatory Activity in Human Colon Organoids

Human colon organoids were maintained in culture medium alone or exposed to lipopolysaccharide with a combination of three pro-inflammatory cytokines (tumor necrosis factor-, interleukin-1{beta} and interferon-{gamma} [LPS-cytokines]) to mimic the environment in the inflamed colon. Untreated organoids and those exposed to LPS-cytokines were concomitantly treated with a multimineral product that has previously been shown to improve barrier structure/function. The organoids were subjected to proteomic analysis to obtain a broad view of the protein changes induced by these interventions. In parallel, confocal fluorescence microscopy and trans-epithelial electrical resistance measurements were used to assess barrier structure/function. The LPS-cytokines altered expression of multiple proteins that influence innate immunity and promote inflammation. Most of these were unaffected by the multi-mineral intervention, though a subset of inflammation-related proteins including fibrinogen-{beta} and -{gamma} chains, phospholipase A2 and SPARC was down-regulated in the presence of the multi-mineral intervention; another subset of proteins with anti-inflammatory, antioxidant or antimicrobial activity was up-regulated by multi-mineral treatment. When used alone, the multi-mineral intervention strongly up-regulated proteins that contribute to barrier formation and tissue strength. Concomitant treatment with LPS-cytokines did not inhibit barrier formation in response to the multimineral intervention. Altogether, the findings suggest that mineral intervention may provide a novel approach to combating inflammation in the colon by improving barrier structure/function as well as by directly altering expression of pro-inflammatory proteins.

molecular biology↗

CALCIUM-INDUCED DIFFERENTIATION IN NORMAL HUMAN COLONOID CULTURES: Cell-cell / cell-matrix adhesion, barrier formation and tissue integrity

Colonoid cultures were established from histologically-normal human colon tissue and maintained in a low-calcium (0.25 mM) medium or in medium supplemented with an amount of calcium (1.5 - 3.0 mM) that was shown in a previous study to induce differentiation in colonoids derived from large adenomas. Calcium alone was compared to Aquamin, a multi-mineral natural product that contains magnesium and detectable levels of 72 additional trace elements in addition to calcium. 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 (CK20) in the absence of intervention. 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 histologically normal human colonoids can undergo differentiation in the presence of a low ambient calcium concentration. However, higher calcium levels can 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.

molecular biology↗