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Gregory M L Patterson - One of the best experts on this subject based on the ideXlab platform.

Richard E. Moore - One of the best experts on this subject based on the ideXlab platform.

Jiyoung Lee - One of the best experts on this subject based on the ideXlab platform.

  • hypolipidemic effect of a blue green Alga nostoc commune is attributed to its nonlipid fraction by decreasing intestinal cholesterol absorption in c57bl 6j mice
    Journal of Medicinal Food, 2015
    Co-Authors: Bohkyung Kim, Youngki Park, Timothy P Carr, Tho X Pham, Yue Yang, Curtis L Weller, Jiyoung Lee
    Abstract:

    We previously demonstrated that Nostoc commune var. sphaeroids Kutzing (NO), a Blue-Green Alga (BGA), exerts a hypolipidemic effect in vivo and its lipid extract regulates the expression of genes involved in cholesterol and lipid metabolism in vitro. The objective of this study was to investigate whether the hypolipidemic effect of NO is attributed to an Algal lipid or a delipidated fraction in vivo compared with Spirulina platensis (SP). Male C57BL/6J mice were fed an AIN-93M diet containing 2.5% or 5% of BGA (w/w) or a lipid extract equivalent to 5% of BGA for 4 weeks to measure plasma and liver lipids, hepatic gene expression, intestinal cholesterol absorption, and fecal sterol excretion. Plasma total cholesterol (TC) was significantly lower in 2.5% and 5% NO-fed groups, while plasma triglyceride (TG) levels were decreased in the 5% NO group compared with controls. However, neither NO organic extract (NOE) nor SP-fed groups altered plasma lipids. Hepatic mRNA levels of sterol regulatory element-binding protein 2, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), carnitine palmitoyltransferase-1α, and acyl-CoA oxidase 1 were induced in 5% NO-fed mice, while there were no significant changes in hepatic lipogenic gene expression between groups. NO, but not NOE and SP groups, significantly decreased intestinal cholesterol absorption. When HepG2 cells and primary mouse hepatocytes were incubated with NOE and SP organic extract (SPE), there were marked decreases in protein levels of HMGR, low-density lipoprotein receptor, and fatty acid synthase. In conclusion, the nonlipid fraction of NO exerts TC and TG-lowering effects primarily by inhibiting intestinal cholesterol absorption and by increasing hepatic fatty acid oxidation, respectively.

  • hypocholesterolemic effect of nostoc commune var sphaeroides kutzing an edible blue green Alga
    European Journal of Nutrition, 2009
    Co-Authors: Heather E Rasmussen, Kara R Blobaum, Elliot D Jesch, Youngki Park, Timothy P Carr, Jiyoung Lee
    Abstract:

    Intake of an edible Blue-Green Alga Nostoc commune var. sphaeroides Kutzing (N. Commune) has been shown to lower plasma total cholesterol concentration, but the mechanisms behind the hypocholesterolemic effect have not been elucidated. To elucidate the mechanisms underlying the cholesterol-lowering effect of N. commune in mice. Male C57BL/6J mice were fed the AIN-93 M diet supplemented with 0 or 5% (wt/wt) dried N. Commune for 4 weeks. Lipid levels in the plasma and liver, intestinal cholesterol absorption and fecal sterol excretion were measured. Expression of hepatic and intestinal genes involved in cholesterol metabolism was evaluated by quantitative realtime PCR. N. commune supplementation significantly reduced total plasma cholesterol and triglyceride concentrations by ~ 20% compared to controls. Intestinal cholesterol absorption was significantly decreased, while fecal neutral sterol output was significantly increased in N. commune-fed mice. mRNA levels of the cholesterol transporters such as Niemann Pick C1 Like 1, scavenger receptor class B type 1, ATP-binding cassette transporters G5 and A1 in small intestine were not significantly different between two groups. Hepatic lipid contents including total cholesterol, triglyceride and free cholesterol in N. commune-fed mice were not significantly altered. However, the expression of cholesterol modulating genes including sterol regulatory element binding protein-2 and 3-hydroxy-3-methylglutaryl coenzyme A reductase were significantly increased in mice fed N. commune. N. commune supplementation exerted a hypocholesterolemic effect in mice, largely in part, by reducing intestinal cholesterol absorption and promoting fecal neutral sterol excretion.

  • repression of proinflammatory gene expression by lipid extract of nostoc commune var sphaeroides kutzing a blue green Alga via inhibition of nuclear factor κb in raw 264 7 macrophages
    Nutrition Research, 2008
    Co-Authors: Youngki Park, Heather E Rasmussen, Kara R Blobaum, Timothy P Carr, Sarah J Ehlers, Vicki L Schlegal, Jiyoung Lee
    Abstract:

    We investigated whether lipid extract from a Blue-Green Alga, N commune, modulates proinflammatory gene expression in RAW 264.7 macrophages. The cells were incubated with N commune lipid extract (0-100 microg/mL) and subsequently activated by LPS (100 ng/mL). Quantitative real-time PCR analysis showed that mRNA abundance of proinflammatory mediators, including TNF-alpha, COX-2, IL-1beta, IL-6, and iNOS, was significantly reduced by N commune lipid extract in a dose-dependent manner. Secretion of TNF-alpha and IL-1beta into cell culture medium was also significantly decreased by N commune lipid extract. Thin-layer chromatography-densitometry analysis showed that N commune lipid extract contained approximately 15% of fatty acids. To determine whether the inhibition of proinflammatory mediator production by N commune lipid extract is primarily conferred by fatty acids in the lipid extract, macrophages were incubated with 100 microg/mL of N commune lipid extract or 15 microg/mL of a fatty acid mixture, which was formulated to reflect the fatty acid composition of N commune lipid extract. The fatty acid mixture significantly reduced RNA abundance of TNF-alpha and COX-2, but to a lesser extent than did the N commune lipid extract, suggesting the presence of additional bioactive compounds with an antiinflammatory property in the lipid extract. As NF-kappaB is a major regulator for the proinflammatory gene expression, we measured its DNA-binding activity. DNA-binding activity of NF-kappaB was significantly reduced by N commune lipid extract. In conclusion, our study suggests that N commune lipid extract represses the expression of proinflammatory genes in RAW 264.7 macrophages, at least in part, by inhibiting the activation of NF-kappaB pathway.

Katsumi Yamaguchi - One of the best experts on this subject based on the ideXlab platform.

Youngki Park - One of the best experts on this subject based on the ideXlab platform.

  • hypolipidemic effect of a blue green Alga nostoc commune is attributed to its nonlipid fraction by decreasing intestinal cholesterol absorption in c57bl 6j mice
    Journal of Medicinal Food, 2015
    Co-Authors: Bohkyung Kim, Youngki Park, Timothy P Carr, Tho X Pham, Yue Yang, Curtis L Weller, Jiyoung Lee
    Abstract:

    We previously demonstrated that Nostoc commune var. sphaeroids Kutzing (NO), a Blue-Green Alga (BGA), exerts a hypolipidemic effect in vivo and its lipid extract regulates the expression of genes involved in cholesterol and lipid metabolism in vitro. The objective of this study was to investigate whether the hypolipidemic effect of NO is attributed to an Algal lipid or a delipidated fraction in vivo compared with Spirulina platensis (SP). Male C57BL/6J mice were fed an AIN-93M diet containing 2.5% or 5% of BGA (w/w) or a lipid extract equivalent to 5% of BGA for 4 weeks to measure plasma and liver lipids, hepatic gene expression, intestinal cholesterol absorption, and fecal sterol excretion. Plasma total cholesterol (TC) was significantly lower in 2.5% and 5% NO-fed groups, while plasma triglyceride (TG) levels were decreased in the 5% NO group compared with controls. However, neither NO organic extract (NOE) nor SP-fed groups altered plasma lipids. Hepatic mRNA levels of sterol regulatory element-binding protein 2, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGR), carnitine palmitoyltransferase-1α, and acyl-CoA oxidase 1 were induced in 5% NO-fed mice, while there were no significant changes in hepatic lipogenic gene expression between groups. NO, but not NOE and SP groups, significantly decreased intestinal cholesterol absorption. When HepG2 cells and primary mouse hepatocytes were incubated with NOE and SP organic extract (SPE), there were marked decreases in protein levels of HMGR, low-density lipoprotein receptor, and fatty acid synthase. In conclusion, the nonlipid fraction of NO exerts TC and TG-lowering effects primarily by inhibiting intestinal cholesterol absorption and by increasing hepatic fatty acid oxidation, respectively.

  • hypocholesterolemic effect of nostoc commune var sphaeroides kutzing an edible blue green Alga
    European Journal of Nutrition, 2009
    Co-Authors: Heather E Rasmussen, Kara R Blobaum, Elliot D Jesch, Youngki Park, Timothy P Carr, Jiyoung Lee
    Abstract:

    Intake of an edible Blue-Green Alga Nostoc commune var. sphaeroides Kutzing (N. Commune) has been shown to lower plasma total cholesterol concentration, but the mechanisms behind the hypocholesterolemic effect have not been elucidated. To elucidate the mechanisms underlying the cholesterol-lowering effect of N. commune in mice. Male C57BL/6J mice were fed the AIN-93 M diet supplemented with 0 or 5% (wt/wt) dried N. Commune for 4 weeks. Lipid levels in the plasma and liver, intestinal cholesterol absorption and fecal sterol excretion were measured. Expression of hepatic and intestinal genes involved in cholesterol metabolism was evaluated by quantitative realtime PCR. N. commune supplementation significantly reduced total plasma cholesterol and triglyceride concentrations by ~ 20% compared to controls. Intestinal cholesterol absorption was significantly decreased, while fecal neutral sterol output was significantly increased in N. commune-fed mice. mRNA levels of the cholesterol transporters such as Niemann Pick C1 Like 1, scavenger receptor class B type 1, ATP-binding cassette transporters G5 and A1 in small intestine were not significantly different between two groups. Hepatic lipid contents including total cholesterol, triglyceride and free cholesterol in N. commune-fed mice were not significantly altered. However, the expression of cholesterol modulating genes including sterol regulatory element binding protein-2 and 3-hydroxy-3-methylglutaryl coenzyme A reductase were significantly increased in mice fed N. commune. N. commune supplementation exerted a hypocholesterolemic effect in mice, largely in part, by reducing intestinal cholesterol absorption and promoting fecal neutral sterol excretion.

  • lipid extract of nostoc commune var sphaeroides kutzing a blue green Alga inhibits the activation of sterol regulatory element binding proteins in hepg2 cells
    Journal of Nutrition, 2008
    Co-Authors: Heather E Rasmussen, Kara R Blobaum, Youngki Park, Sarah J Ehlers, Fan Lu
    Abstract:

    : Nostoc commune var. sphaeroides Kutzing (N. commune), a Blue-Green Alga, has been used as both a food ingredient and in medicine for centuries. To determine the effect of N. commune on cholesterol metabolism, N. commune lipid extract was incubated at increasing concentrations (25-100 mg/L) with HepG2 cells, a human hepatoma cell line. The addition of N. commune lipid extract markedly reduced mRNA abundance of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) and LDL receptor (LDLR) (P < 0.05), with a concomitant decrease in their protein expression (P < 0.001). Reduced HMGR activity by 90% with N. commune lipid extract confirmed the inhibitory role of N. commune in cholesterol synthesis (P < 0.006). To elucidate a molecular mechanism underlying the repression of HMGR and LDLR by N. commune lipid extract, expression of sterol regulatory element binding protein 2 (SREBP-2) was assessed. Whereas mRNA for SREBP-2 remained unchanged, SREBP-2 mature protein was reduced by N. commune (P < 0.009). In addition, N. commune lipid extract also decreased SREBP-1 mature protein by approximately 30% (P < 0.002) and reduced the expression of SREBP-1-responsive genes such as fatty acid synthase and stearoyl CoA desaturase 1 (SCD-1) (P < 0.05). Therefore, our results demonstrate that N. commune lipid extract inhibits the maturation process of both SREBP-1 and -2, resulting in a decrease in expression of genes involved in cholesterol and fatty acid metabolism.

  • repression of proinflammatory gene expression by lipid extract of nostoc commune var sphaeroides kutzing a blue green Alga via inhibition of nuclear factor κb in raw 264 7 macrophages
    Nutrition Research, 2008
    Co-Authors: Youngki Park, Heather E Rasmussen, Kara R Blobaum, Timothy P Carr, Sarah J Ehlers, Vicki L Schlegal, Jiyoung Lee
    Abstract:

    We investigated whether lipid extract from a Blue-Green Alga, N commune, modulates proinflammatory gene expression in RAW 264.7 macrophages. The cells were incubated with N commune lipid extract (0-100 microg/mL) and subsequently activated by LPS (100 ng/mL). Quantitative real-time PCR analysis showed that mRNA abundance of proinflammatory mediators, including TNF-alpha, COX-2, IL-1beta, IL-6, and iNOS, was significantly reduced by N commune lipid extract in a dose-dependent manner. Secretion of TNF-alpha and IL-1beta into cell culture medium was also significantly decreased by N commune lipid extract. Thin-layer chromatography-densitometry analysis showed that N commune lipid extract contained approximately 15% of fatty acids. To determine whether the inhibition of proinflammatory mediator production by N commune lipid extract is primarily conferred by fatty acids in the lipid extract, macrophages were incubated with 100 microg/mL of N commune lipid extract or 15 microg/mL of a fatty acid mixture, which was formulated to reflect the fatty acid composition of N commune lipid extract. The fatty acid mixture significantly reduced RNA abundance of TNF-alpha and COX-2, but to a lesser extent than did the N commune lipid extract, suggesting the presence of additional bioactive compounds with an antiinflammatory property in the lipid extract. As NF-kappaB is a major regulator for the proinflammatory gene expression, we measured its DNA-binding activity. DNA-binding activity of NF-kappaB was significantly reduced by N commune lipid extract. In conclusion, our study suggests that N commune lipid extract represses the expression of proinflammatory genes in RAW 264.7 macrophages, at least in part, by inhibiting the activation of NF-kappaB pathway.

  • repression of proinflammatory gene expression by lipid extract of nostoc commune var sphaeroides kutzing a blue green Alga via inhibition of nuclear factor κb in raw 264 7 macrophages
    Nutrition Research, 2008
    Co-Authors: Youngki Park, Heather E Rasmussen, Kara R Blobaum, Sarah J Ehlers, Fan Lu, Vicki L Schlegal, Timothy P Carr
    Abstract:

    Abstract We investigated whether lipid extract from a Blue-Green Alga, N commune , modulates proinflammatory gene expression in RAW 264.7 macrophages. The cells were incubated with N commune lipid extract (0-100 μ g/mL) and subsequently activated by LPS (100 ng/mL). Quantitative real-time PCR analysis showed that mRNA abundance of proinflammatory mediators, including TNF- α , COX-2, IL-1 β , IL-6, and iNOS, was significantly reduced by N commune lipid extract in a dose-dependent manner. Secretion of TNF- α and IL-1 β into cell culture medium was also significantly decreased by N commune lipid extract. Thin-layer chromatography–densitometry analysis showed that N commune lipid extract contained approximately 15% of fatty acids. To determine whether the inhibition of proinflammatory mediator production by N commune lipid extract is primarily conferred by fatty acids in the lipid extract, macrophages were incubated with 100 μ g/mL of N commune lipid extract or 15 μ g/mL of a fatty acid mixture, which was formulated to reflect the fatty acid composition of N commune lipid extract. The fatty acid mixture significantly reduced RNA abundance of TNF- α and COX-2, but to a lesser extent than did the N commune lipid extract, suggesting the presence of additional bioactive compounds with an antiinflammatory property in the lipid extract. As NF- κ B is a major regulator for the proinflammatory gene expression, we measured its DNA-binding activity. DNA-binding activity of NF- κ B was significantly reduced by N commune lipid extract. In conclusion, our study suggests that N commune lipid extract represses the expression of proinflammatory genes in RAW 264.7 macrophages, at least in part, by inhibiting the activation of NF- κ B pathway.