Project description:Fucoidan, a sulfated polysaccharide extracted from brown seaweeds, possesses many biological activities including anti-inflammatory and anti-oxidant activities. We aimed to investigate the protective effects of fucoidan on dyslipidemia and atherosclerosis in apolipoprotein E-deficient mice (ApoEshl mice) and to elucidate its molecular targets in the liver by using a transcriptomic approach. For 12 weeks, ApoEshl mice were fed a high-fat diet (HFD) supplemented with either 1% or 5% fucoidan. Fucoidan supplementation significantly reduced tissue weight (liver and white adipose tissue), blood lipid, total-cholesterol (TC), triglyceride (TG), non-high density lipoprotein-cholesterol (Non-HDL-C), and glucose levels in HFD-fed ApoEshl mice but increased plasma lipoprotein lipase (LPL) activity and HDL-C levels. Fucoidan also reduced hepatic steatosis levels (liver size, TC and TG levels, and lipid peroxidation) and increased white adipose tissue LPL activity. DNA microarray analysis and quantitative reverse transcription-polymerase chain reaction demonstrated differential expression of genes encoding proteins involved in lipid metabolism, energy homeostasis, and insulin sensitivity, by activating Ppara and inactivating Srebf1. Fucoidan supplementation markedly reduced the thickness of the lipid-rich plaque, lipid peroxidation, and foaming macrophage accumulation in the aorta in HFD-fed ApoEshl mice. Thus, fucoidan supplementation appears to have anti-dyslipidemic and anti-atherosclerotic effects by inducing LPL activity and inhibiting the effects of inflammation and oxidative stress in HFD-fed ApoEshl mice.
Project description:Fucoidan is a high-molecular polysaccharide whose main constituent is sulfated fucose. Extensive studies have demonstrated numerous interesting biological activities for fucoidan. We specifically focused on the anti-proliferation activity of fucoidan and examined the underlying mechanism in MKN45 gastric cancer cells. BrdU assay revealed that fucoidan impeded the MKN45 cell cycle by approximately 50%, and clonogenic assay also showed that fucoidan inhibited cell proliferation. Preliminary examinations of fucoidan using LDH assay showed no immediate cytotoxic effects at 24-h exposure. However, longer time courses revealed inhibition of cell growth at 4 days in a dose-dependent manner. Microarray analysis in MKN45 cells treated with fucoidan identified genes that were upregulated and downregulated in response to fucoidan, including MAP3K5, or ASK1 (apoptosis signal-regulating kinase), which was upregulated by 1.38-fold. Western blot confirmed that fucoidan increased ASK1 protein levels, while reducing the levels of phosphorylated ASK1. Reduction of ASK1 by siRNA decreased proliferation of MKN45 cells. Our findings show that fucoidan may suppress cellular proliferation and DNA synthesis in MKN45 cells by suppressing the ASK1-p38 signaling pathway through reduction of phosphorylated ASK1 levels.
Project description:Oligo-fucoidan (OF), a sulfated polysaccharide extracted from brown seaweed, exhibits anti-inflammation and antitumor effects, however, knowledge concerning the detailed mechanism of oligo-fucoidan on liver cells is obscure. In this study, we investigate the effect of oligo-fucoidan in normal hepatocytes using transcriptomic analysis. Using an oligo-fucoidan oral gavage in adult wild-type zebrafish, we then used microarrays to detail the global programme of gene expression after fucoidan treatment and identified distinct classes of up- and down-regulated genes during this process.
Project description:Obesity is a risk factor for Osteoarthritis (OA), the greatest cause of disability in the US. The impact of obesity on OA is driven by systemic inflammation, now understood to be caused by an altered gut microbiome. Oligofructose, a non-digestible prebiotic fiber, can correct the obese gut microbiome, suggesting a novel approach to treat the OA of obesity. Here we report that in the obese murine gut, beneficial Bifidobacteria are lost while key proinflammatory species gain in abundance. A downstream systemic inflammatory signature culminates with accelerated knee OA. Oligofructose supplementation corrects the obese gut microbiome in part by supporting key commensal microflora, particularly Bifidobacterium pseudolongum. This leads to reduced inflammation in the colon, circulation and knee, and protection from OA. This novel recognition of a gut microbiome-OA connection sets the stage for discovery of new OA therapeutics targeting specific microbes inhabiting the intestinal space to inhibit disease pathology.
Project description:Hepatocellular carcinoma is the fourth leading cause of cancer-related deaths worldwide. Many carcinogens induce inflammation and cirrhosis, and eventually develop into liver cancer. Fucoidan is sulfated polysaccharide that is mainly found in brown seaweeds. In this study, we investigated the effects and mechanisms of low molecular weight fucoidan (i.e. oligo-fucoidan) preventing hepatocarcinogenesis using HBx,Src, and HBx,Src,p53-/+ transgenic zebrafish liver cancer model. Using an oligo-fucoidan oral gavage in adult transgenic zebrafish, we then used microarrays to detail the global programme of gene expression after fucoidan treatment and identified distinct classes of up- and down-regulated genes during this process.
Project description:Dietary restriction has shown benefits in physiological, metabolic, and molecular signatures associated with aging. In mice, periodic dietary restriction, that accompanies cyclical periods of reduced calories, mitigates aging phenotypes, yet the effects of this periodic restriction in higher order, genetically heterogenous mammals, have not been investigated. Reducing caloric intake in middle-aged Rhesus Macaques for four days followed by ad libitum eating for ten days, repeated for six cycles, led to significant changes in body composition, metabolome, and microbiome of the restricted monkeys compared to their ad libitum fed (age and sex matched) controls. These changes were also associated with stabilized blood parameters. The changes in metabolome, microbiome, and body compositions were additive, with consistent but increasingly pronounced changes in later cycles, suggesting sustaining benefits in non-human primates. These results suggest this type of cyclical dietary restriction, that is easy to adhere to, will also have translational benefits in humans while enhancing aging-associated parameters.
Project description:We systematically investigated the responses of five human gut microbiomes to 21 common sweeteners, using an approach combining high-throughput ex vivo microbiome culturing and metaproteomics to quantify functional changes in different taxa. Hierarchical clustering based on metaproteomic responses of individual microbiomes resulted in two clusters. The first cluster was composed of non-caloric artificial sweeteners (NAS) and two sugar alcohols with shorter carbon backbones (4-5 carbon atoms), and the second cluster was composed of sugar alcohols with longer carbon backbones. The metaproteomic functional responses of the second cluster were similar to the prebiotic fructooligosaccharides and kestose, indicating that these sugar alcohol-type sweeteners have potential prebiotic functions.
Project description:This study use different ice recrystalization inhibitors (IRIs) for better storing live microbiota. We evaluated whether the addition of IRIs can improve the cultivibility of microbiome and maintain their resposnes to prebiotic kestose. Frozen or fresh microbiota were cultured with or without kestose for 24 hours, and microbiota samples were collected for metaproteomics analysis.
Project description:Radiotherapy (RT) often causes unwanted side effects such as radiation-induced fibrosis (RIF) and second malignancies (SM). Fucoidan, a sulfated polysaccharide extracted from brown seaweed, has many biological effects including anti-inflammation and anti-tumor. In the present study, we investigated the radioprotective effect of Oligo-Fucoidan (OF) using zebrafish animal model. Using an oligo-fucoidan oral gavage in wild-type and adult transgenic zebrafish, we then used microarrays to detail the global programme of gene expression after fucoidan treatment and identified distinct classes of up- and down-regulated genes during this process.