High fibre diets are associated with reduced risk of type 2 diabetes mellitus (T2DM). This may be due to short-chain-fatty-acids (SCFA) influencing insulin resistance and secretion via changes in free-fatty-acids (FFA) and specific gut hormones. We aimed to determine the postprandial effects of inulin, a fermentable, soluble fibre in healthy subjects. Twelve fasted subjects were studied for 6 hours after either 80g high fructose corn syrup (HFCS), 56g HFCS plus 24g inulin, or 56g HFCS drinks using a randomized, cross-over design. SCFA were higher after inulin beginning at 4 hours. FFA were lower 4 hours after inulin than 56gHFCS. GLP-1 was higher 30 minutes after inulin than 56 and 80HFCS, while ghrelin was lower from 4-6 hours after inulin. The results support the hypothesis that inulin and SCFA generated from colonic fermentation of dietary fibre may improve insulin resistance and secretion via modulation of FFA and specific gut hormones.

High fibre diets are associated with reduced risk of type 2 diabetes mellitus (T2DM). This may be due to short-chain-fatty-acids (SCFA) influencing insulin resistance and secretion via changes in free-fatty-acids (FFA) and specific gut hormones. We aimed to determine the postprandial effects of inulin, a fermentable, soluble fibre in healthy subjects. Twelve fasted subjects were studied for 6 hours after either 80g high fructose corn syrup (HFCS), 56g HFCS plus 24g inulin, or 56g HFCS drinks using a randomized, cross-over design. SCFA were higher after inulin beginning at 4 hours. FFA were lower 4 hours after inulin than 56gHFCS. GLP-1 was higher 30 minutes after inulin than 56 and 80HFCS, while ghrelin was lower from 4-6 hours after inulin. The results support the hypothesis that inulin and SCFA generated from colonic fermentation of dietary fibre may improve insulin resistance and secretion via modulation of FFA and specific gut hormones.

Thesis (Ph. D.)--University of Hong Kong, 1988.

Not available / text

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

Cholesterol and fatty acyl-coenzymeA thioesters are signalling molecules with role in regulation of genes involved in lipid and glucose transport and metabolism. The studies described herein focused on three proteins that bind lipids and have different cellular functions: steroidogenic acute regulatory protein (StAR), hepatocyte nuclear factor-4a (HNF-4a) and acyl-CoA binding protein (ACBP). First, StAR mediates delivery of cholesterol to inner mitochondrial membrane in steroidogenesis by a poorly understood mechanism. In our studies, fluorescent NBD-cholesterol binding assays demonstrate that StAR binds cholesterol at two binding sites with 32 nM Kds and circular dichroism spectra show that cholesterol binding results in changes of StAR secondary structure. Fluorescent sterol exchange assays between donor and acceptor mitochondrial membranes indicate that StAR significantly increased the formation of rapidly transferable cholesterol domains. Second, HNF-4a, a nuclear receptor, had been shown to bind fatty acyl-CoAs as natural ligands with apparent low affinities obtained with radiolabeled ligand binding assays. Our fluorescence spectroscopy studies demonstrate that HNF-4a ligand binding domain (HNF-4aLBD) binds acyl-CoAs at a single binding site with Kds of 1.6-4 nM. Fluorescence resonance energy transfer (FRET) between HNF-4aLBD tryptophan residues and cis-parinaroyl-CoA yielded an intermolecular distance of 42 Â thus pointing to direct molecular interaction. Third, although ACBP has been detected in the nucleus, it is not known whether ACBP may directly and/or functionally interact with a nuclear acyl-CoA binding protein such as HNF-4a to regulate transcription. Our present studies in vitro and in intact cultured cells, including circular dichroism of HNF-4a in the presence of ACBP, coimmunoprecipitation of HNF-4a/ACBP complexes, ACBP and HNF-4a colocalization in nuclei of cells by confocal microscopy demonstrate a physical association of ACBP and HNF-4a. FRET microscopy data indicated an intermolecular distance of 53 Â between ACBP and HNF-4a in rat hepatoma cells. Functional assays (transactivation of an HNF4a-dependent reporter gene) showed significant increase in the presence of ACBP in two different cell lines. Expression of ACBP anti-sense RNA decreased HNF-4a-mediated transactivation, pointing to a role of ACBP in co-regulating HNF-4a-dependent transcription.

No description available.

Omega-3 fatty acids are increasingly recognised as playing an important role in human brain development and mental health. The polyunsaturated fatty acids (PUFAs) include omega-3 and omega-6 fats which are essential fatty acids (EFAs), consumed via the diet. Omega-3 fatty acids are particularly abundant in fish oils. The omega-3 fatty acids are being focused on for their role in depression, the main types being docosahexaenoic acid (DHA), which is abundant in neural tissue, and also eicosapentaenoic acid (EPA) which is biologically very active. There is an emerging literature in relation to omega-3 fatty acid blood levels in depression and the effects of treatment with omega-3. Strong epidemiological evidence has also been published indicating an association between a population's fish intake and depression rates. A specific research focus on omega-3 as a treatment for depression in the perinatal period is also starting to emerge. The importance of this particular area is enhanced by the knowledge that omega-3 depletion occurs during the perinatal period due to fetal diversion for neurodevelopment. In view of the lay public promotion of omega-3 and its appeal to women as a 'natural therapy', there is a need to scientifically evaluate its effectiveness to treat depression in the perinatal period. It is also important to investigate omega-3 as an alternative to antidepressants given the ongoing uncertainties regarding their safety in pregnancy. In this thesis a literature review presents current research relating to this field. This is followed by a description of the methodology and results for the two trials conducted. The results of the double-blind randomised placebo controlled trial of omega-3 as a treatment for depression in the perinatal period were essentially negative. However this result is limited by the small sample size in the study and therefore it may be unwise to interpret the result as conclusive. The case-control study confirmed the hypothesis that omega-3 levels were more depleted in depressed women compared to non-depressed women. A discussion of the results and trial limitations then follows in the thesis. It is concluded that further larger studies are warranted in this area.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 104-111). Also available on the World Wide Web.

Thesis (M.S.)--Michigan State University. Dept. of Chemical Engineering and Material Science, 2008. / Title from PDF t.p. (viewed on July 29, 2009) Includes bibliographical references (p. 34-41). Also issued in print.