Effects of Panax ginseng on hyperglycemia, hypertension, and hyperlipidemia: A systematic review and meta-analysis.

Panax ginseng is a medicinal plant is a material with various pharmacological activities and research suggests that it is particularly effective in representative metabolic diseases such as hyperglycemia, hypertension, and hyperlipidemia. Therefore, in this study, systematic review and meta-analysis were performed to investigate the comprehensive effect of P. ginseng on metabolic parameters representing these metabolic diseases. A total of 23 papers were collected for inclusion in the study, from which 27 datasets were collected. The investigational products included P. ginseng and Korean Red ginseng. Across the included studies, the dose ranged from 200 mg to 8 g and the supplementation period lasted from four to 24 weeks. The study subjects varied from healthy adults to those with diabetes, hypertension, obesity, and/or hyperlipidemia. As a result of the analysis, the levels of glucose and insulin area under the curves, % body fat, systolic and diastolic blood pressures, total cholesterol, triglycerides, and low-density lipoprotein cholesterol were significantly reduced in the P. ginseng group as compared with in the placebo group. In conclusion, P. ginseng supplementation may act as an adjuvant to prevent the development of metabolic diseases by improving markers related to blood glucose, blood pressure, and blood lipids.

Tamarixetin Abrogates Adipogenesis Through Inhibiting p300/CBP-Associated Factor Acetyltransferase Activity in 3T3-L1 Preadipocyte Cells.

Tamarixetin (TX) is an O-methylated flavonoid naturally derived from quercetin. TX has bioactive properties; however, whether it shows antilipogenic activity remains unknown. Therefore, in the present study, we aimed to determine the antilipogenic effects of TX using 3T3-L1 adipocytes. The 3T3-L1 adipocytes were cultured in a differentiation medium with or without TX. Lipid accumulation was diminished and the mRNA expression of lipogenesis-related genes was decreased following TX treatment. We found that TX exhibited antilipogenic effects by inhibiting the expression of p300/CBP-associated factor (pCAF), a histone acetyltransferase, as confirmed by pCAF knockdown. Furthermore, TX inhibited both pCAF expression and its activity, thereby reducing the total acetylation level of nonhistone and histone proteins. Finally, TX decreased the expression of CCAAT/enhancer-binding protein alpha and beta (CEBPα and CEBPß), and peroxisome proliferator-activated receptor γ along with pCAF expression during adipogenesis of 3T3-L1 cells in a time-dependent manner. Collectively, our findings suggest that TX is a potent antilipogenic agent derived from natural products and may be used as a pCAF inhibitor.

Barley Sprout Water Extract and Saponarin Mitigate Triacylglycerol Accumulation in 3T3-L1 Adipocytes.

The mechanisms of action responsible for the reported hypolipidemic activity of barley sprouts have yet to be elucidated. The objective of this study was to compare the content of saponarin (the sole flavonoid present in barley sprout leaves), hypolipidemic activity between barley sprout water extract (BSW) and barley sprout ethanol extract (BSE), and the associated relevance to hypolipidemic activity in 3T3-L1 preadipocytes. BSW elicited superior antiadipogenic effects when compared with BSE in MDI mixture [IBMX 0.5 mM + dexamethasone 1 µM + insulin 1 µg/mL]-treated 3T3-L1 preadipocytes. BSW attenuated MDI-mediated triacylglycerol (TAG) accumulation by inhibiting fatty acid synthase (FAS). FAS protein expression was markedly and dose dependently attenuated by BSW, with higher doses suppressing expression to a level equivalent to the controls. BSW also significantly attenuated MDI-mediated increases in the expression of genes involved in TAG synthesis as well as FAS in 3T3-L1 preadipocytes. High-performance liquid chromatography analysis indicated that BSW contains more than four times more saponarin than BSE. Further investigation of saponarin-mediated hypotriacylglycerolemic activity and related gene expression revealed that saponarin significantly inhibited TAG accumulation, which was attributed to reductions in TAG synthesis-related gene expression. Taken together, these findings provide a basis for further development of barley sprout extract for functional health food purposes.

AMPK Activity: A Primary Target for Diabetes Prevention with Therapeutic Phytochemicals.

Diabetes is a metabolic syndrome characterized by inadequate blood glucose control and is associated with reduced quality of life and various complications, significantly shortening life expectancy. Natural phytochemicals found in plants have been traditionally used as medicines for the prevention of chronic diseases including diabetes in East Asia since ancient times. Many of these phytochemicals have been characterized as having few side effects, and scientific research into the mechanisms of action responsible has accumulated mounting evidence for their efficacy. These compounds, which may help to prevent metabolic syndrome disorders including diabetes, act through relevant intracellular signaling pathways. In this review, we examine the anti-diabetic efficacy of several compounds and extracts derived from medicinal plants, with a focus on AMP-activated protein kinase (AMPK) activity.

Black Mulberry Extract Elicits Hepatoprotective Effects in Nonalcoholic Fatty Liver Disease Models by Inhibition of Histone Acetylation.

Epigenetic regulation by histone acetyltransferase (HAT) is associated with various biological processes and the progression of diseases, including nonalcoholic fatty liver disease (NAFLD). The objective of this study was to investigate whether the hypolipidemic properties of black mulberry (Morus atropurpurea Roxb.) fruit extract (BME) contribute toward protection against NAFLD by HAT inhibition. HepG2 cells were treated with oleic and palmitic acids to induce lipid accumulation, which was significantly attenuated by the treatment with BME at 50 and 100 µg/mL. BME also markedly reduced the expression of proteins associated with lipogenesis, which was attributed to the BME-mediated downregulation of lipogenic genes in HepG2 cells. BME significantly inhibited in vitro total HAT and p300 activities. In addition, BME suppressed total acetylated lysine as well as specific histone acetylation of proteins H3K14 and H3K27 in HepG2 cells. Mice were then fed with either a chow diet or western diet (WD), with or without BME (1%, w/w) supplementation, for 12 weeks to confirm hypolipidemic activity of BME. BME attenuated serum nonesterified fatty acids and low-density lipoprotein (LDL) cholesterol levels, which was likely associated with the downregulation of hepatic lipogenic gene expression in WD-fed obese mice. Taken together, the hypolipidemic activity of BME was observed in HepG2 cells treated with fatty acids as well as in livers of obese mice, and the hepatoprotection of BME is likely associated with the inhibition of acetylation. Further investigation is warranted to determine whether BME can be developed into an efficacious dietary intervention to attenuate the progression of NAFLD by epigenetic regulation in clinical settings.

Preparation of Low-Diacylglycerol Cocoa Butter Equivalents by Hexane Fractionation of Palm Stearin and Shea Butter.

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.

Anacardic Acid Suppresses Adipogenesis Through Inhibition of the Hsp90/Akt Signaling Pathway in 3T3-L1 Preadipocytes.

Anacardic acid (AA), a major component of cashew nut shell liquid, has extensive bioactivities. However, little is known about its antiadipogenic properties or the mechanism that underpins them. The aim of this study was to investigate the effect of AA on 3T3-L1 preadipocyte differentiation and its mechanisms of action. AA inhibits lipid accumulation during adipogenesis in 3T3-L1 preadipocyte (IC50 = 25.45 µM). AA abrogates mRNA expressions of the genes implicated in lipogenesis and their transcription factors, especially Pparg and Cebpa. Furthermore, antibody microarray and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis results showed that the proteins implicated in the Akt signaling pathway were most likely altered by AA. Notably, upon AA treatment, heat shock protein 90 (Hsp90), a positive regulator of Akt, was decreased, resulting in Akt degradation. These findings indicate that AA, a natural product that acts as a Hsp90/Akt signaling inhibitor, may be a possible antiadipogenic agent.

Isolation and compositional analysis of galactoglycerolipids from perilla [Perilla frutescens (L.) Britton] leaves and comparison to the galactoglycerolipids from spinach and parsley.

The aim of this study was to isolate monogalactosyldiacylglycerols (MGDGs) and digalactosyldiacylglycerols (DGDGs) from perilla [Perilla frutescens (L.) Britton] and to investigate their fatty acid profiles. Perilla displayed the greatest total MGDG and DGDG content among the three types of leaf vegetables tested, that is, spinach, parsley, and perilla, containing 0.16 g/100 g MGDG and 0.04 g/100 g DGDG (on wet weight basis). High purity MGDG (approximately 97 g/100 g) and DGDG (approximately 86 g/100 g) were isolated from perilla chloroform/methanol (2:1, v/v) extracts by two-step silica gel column chromatography. MGDGs were primarily composed of 18:3n-3 and 16:3n-3, predominantly located at the sn-1 and sn-2 positions, respectively. In DGDG, 18:3n-3 and 16:0 were the most abundant fatty acids and were primarily found at the sn-1 and sn-2 positions, respectively. PRACTICAL APPLICATION: MGDGs and DGDGs are the most prevalent forms of galactoglycerolipids found in leaf vegetables including perilla and have been shown to exert health-beneficial effects, such as antitumor, anti-inflammatory, anticancer, and appetite-suppressing activities. Both MGDGs and DGDGs possess emulsifying properties. The present study may help better understand the health-beneficial effects of MGDG and DGDG from perilla, by providing total composition and positional distribution of the fatty acids. The present study also successfully established a protocol to isolate high purity MGDG and DGDG from perilla, thereby increasing their possible use as an ingredient in foods and nutraceuticals.

Butein Synergizes with Statin to Upregulate Low-Density Lipoprotein Receptor Through HNF1α-Mediated PCSK9 Inhibition in HepG2 Cells.

Downregulation of the low-density lipoprotein (LDL) receptor (LDLR) can lead to hypercholesterolemia and related conditions, including cardiovascular diseases. Statins are a class of LDL cholesterol-lowering agents and are best-selling medications for patients at high risk of developing cardiovascular diseases. Indeed, statins upregulate LDLR and proprotein convertase subtilisin/kexin type 9a (PCSK9), leading to LDLR lysosomal degradation, which interferes with the attenuation of hypercholesterolemia. In the present study, butein was found to decrease extracellular PCSK9 levels by reducing its mRNA expression, which was attributable to butein-mediated downregulation of HNF1α in HepG2 cells. Butein-mediated PCSK9 inhibition further reversed LDLR protein synthesis inhibition, which possibly occurred through butein-mediated inhibition of LDLR degradation. When treated as a combination of butein and a statin, butein reduced statin-mediated enhancement of PCSK9 protein expression. This resulted in a synergistic enhancement of LDLR protein expression, whereas butein alone marginally increased LDLR protein expression. These findings suggest that butein, a novel PCSK9 inhibitor, may be a potential alternative or adjunct to statin treatment.

Ethanol Extract of Ligularia fischeri Inhibits the Lipopolysaccharide-Induced Inflammatory Response by Exerting Anti-Histone Acetyltransferase Activity to Negatively Regulate p65.

Histone acetyltransferase (HAT) activity is well established to regulate inflammatory responses. In contrast, the mechanisms by which natural nutritional extracts influence epigenetic mechanisms to regulate inflammation have not yet been thoroughly investigated. Thus, in the present study, we observed that the anti-HAT activity exerted by an ethanol extract of Ligularia fischeri (ELF) inhibited inflammation. Specifically, we used a cell-free system to show that ELF attenuates HAT activity. We also demonstrated that ELF decreases lipopolysaccharide (LPS)-induced HAT mRNA and protein expression levels in Raw 264.7 cells, and thereby attenuates inflammation-induced patterns of hyperacetylation at nonhistone and histone-H4 proteins. Interestingly, we found that ELF blocked p65 translocation in LPS-stimulated Raw 264.7 cells by attenuating acetylation at lysine residue 310 of p65. Finally, we investigated whether ELF reduces the inflammatory cytokines, IL-6, IL-1ß, and TNFα, using its HAT inhibitor activity. Taken together, these results suggest that ELF negatively regulates inflammatory responses by inhibiting HATs and HAT activity.

Genome-wide analysis of DNA methylation identifies novel differentially methylated regions associated with lipid accumulation improved by ethanol extracts of Allium tubersosum and Capsella bursa-pastoris in a cell model.

Hepatic steatosis is the most common chronic liver disease in Western countries. Both genetic and environmental factors are known as causes of the disease although their underlying mechanisms have not been fully understood. This study investigated the association of DNA methylation with oleic acid-induced hepatic steatosis. It also examined effects of food components on DNA methylation in hepatic steatosis. Genome-wide DNA methylation of oleic acid (OA)-induced lipid accumulation in vitro cell model was investigated using reduced representation bisulfite sequencing. Changes of DNA methylation were also analyzed after treatment with food components decreasing OA-induced lipid accumulation in the model. We identified total 81 regions that were hypermethylated by OA but hypomethylated by food components or vice versa. We determined the expression of seven genes proximally located at the selected differentially methylated regions. Expression levels of WDR27, GNAS, DOK7, MCF2L, PRKG1, and CMYA5 were significantly different between control vs OA and OA vs treatment with food components. We demonstrated that DNA methylation was associated with expression of genes in the model of hepatic steatosis. We also found that food components reversely changed DNA methylation induced by OA and alleviated lipid accumulation. These results suggest that DNA methylation is one of the mechanisms causing the hepatic steatosis and its regulation by food components provides insights that may prevent or alleviate lipid accumulation.

Preparation of Pinolenic Acid Concentrates from Pine Nut Oil Fatty Acids by Solvent Fractionation.

Pinolenic acid (PLA), which is a fatty acid (FA) exclusively found in the oils of edible pine nuts, has an appetite-suppression effect, thereby being effective to reduce body weight in humans. PLA concentrates would be suitable for use in functional foods and nutraceuticals due to the health benefits of PLA. PLA concentrates were prepared from free FA (FFA) obtained from pine nut oil using solvent fractionation. Siberian pine nut oil containing 18.3 wt% PLA was used as the starting material for the fractionation. The fractionation was performed in n-hexane at ultra-low temperatures down to -85°C. The PLA concentrates produced under the optimal conditions established in this study (temperature, -85°C; n-hexane-to-FFA ratio (v/w), 30:1; fractionation time, 36 h) contained 69.8 wt% PLA. The yield of PLA was 77.4 wt% of the initial PLA weight in the FFA. These results suggest that solvent fractionation is a more effective approach to prepare PLA concentrates with higher PLA contents at a particular yield of PLA than published methods using urea crystallization (e.g., PLA content = ~47 wt%, yield of PLA = ~77 wt%, Woo et al. (2016)) or lipase-catalyzed reactions (e.g., PLA content = ~30 wt%, yield of PLA = ~61 wt%, Lee et al. (2011)). The resulting PLA concentrates contained 11 of the 12 different species of FA present in the FFA, thereby indicating that the PLA concentrates prepared by solvent fractionation have more diverse FA profiles than those prepared by urea crystallization (e.g., 7 species of FA, Woo et al. (2016)).

Enzymatic Synthesis of Structured Monogalactosyldiacylglycerols Enriched in Pinolenic Acid.

We enzymatically prepared structured monogalactosydiacylglycerols (MGDGs) enriched in pinolenic acid (PLA). PLA-enriched free fatty acids (FFAs) containing ∼86 mol % PLA were produced from an FFA fraction obtained from pine nut oil (PLA content, ∼13 mol %) by urea crystallization. Commercial MGDGs (5 mg) were acidolyzed with PLA-enriched FFAs using four commercial immobilized lipases as biocatalysts. The reaction was performed in acetone (4 mL) in a stirred-batch reactor. Lipozyme RM IM (immobilized Rhizomucor miehei lipase) was the most effective biocatalyst for the reaction. Structured MGDGs containing 42.1 mol % PLA were obtained under optimal reaction conditions: temperature, 25 °C; substrate molar ratio, 1:30 (MGDGs/PLA-enriched FFAs); enzyme loading, 20 wt % of total substrates; and reaction time, 36 h. The structured MGDGs were separated from the reaction products at a purity of 96.6 wt % using silica column chromatography. The structured MGDGs could be possibly used as emulsifiers with appetite-suppression effects.

Schisandra chinensis berry extract protects against steatosis by inhibiting histone acetylation in oleic acid-treated HepG2 cells and in the livers of diet-induced obese mice.

We hypothesized that hepatic steatosis could be mitigated by the hypolipidemic activity of Schisandra chinensis berry ethanol extract (SCE) via the inhibition of histone acetyltransferase (HAT) activity. HepG2 cells treated with oleic acid (OA) in the presence of SCE exhibited reduced OA-induced lipid accumulation, which was likely mediated by reductions in SREBP-1c expression. SCE attenuated the acetylation of total lysine and H3K9 that was otherwise increased by OA. Male obese mice fed with either a low-fat diet or Western diet exhibited reduced body and liver weights when supplemented with 1% SCE. The SCE-mediated attenuation of hepatic lipid accumulation was accompanied by a decrease in the expression of lipogenic genes. SCE also attenuated the expression of acetylated lysine and non-acetylated forms of H3K9 acetylation in the livers of these mice. Taken together, these results suggest that SCE has potential for further development as a novel therapeutic agent for the prevention of steatosis.

Welsh onion extract inhibits PCSK9 expression contributing to the maintenance of the LDLR level under lipid depletion conditions of HepG2 cells.

Statins mediate the transactivation of PCSK9, which in turn limits their cholesterol-lowering effects via LDL receptor (LDLR) degradation. The objective of the present study was to investigate the mechanism of action by which Welsh onion (Allium fistulosum L. [family Amaryllidaceae]) extract (WOE) regulates LDLR and PCSK9. HepG2 cells were cultured under lipid depletion conditions using a medium supplemented with delipidated serum (DLPS). WOE (50, 100, 200, and 400 µg ml-1) significantly attenuated the DLPS-mediated increases in LDLR, PCSK9, and SREBP2 gene expression. While WOE treatment maintained the DLPS-mediated increases in LDLR protein expression, it dose-dependently and significantly attenuated the DLPS-mediated increases in the protein content of PCSK9. The suppression of PCSK9 was associated with the WOE-mediated reductions in SREBP2, but not HNF1α. WOE also dose-dependently reduced PCSK9 protein expression that was otherwise markedly induced by concomitant statin treatment. WOE-mediated PCSK9 inhibition contributed to LDLR lysosomal degradation suppression, and subsequent LDLR protein stabilization. HPLC analysis indicated that WOE contains kaempferol, quercetin, ferulic acid, and p-coumaric acid. Kaempferol and p-coumaric acid contributed to the maintenance of LDLR expression by inhibiting PCSK9 in lipid depleted HepG2 cells. Altogether, these findings suggest that WOE inhibits PCSK9 transcription and protein expression via the reduction of SREBP2, and decreased PCSK9 further contributes to LDLR degradation prevention and LDLR protein stabilization under conditions of lipoprotein deficiency. The PCSK9 inhibition-mediated mechanism of WOE was likely attributed to the action of kaempferol and p-coumaric acid present in WOE.

Hypolipidemic Activity of Quercus acutissima Fruit Ethanol Extract is Mediated by Inhibition of Acetylation.

The acetylation of histone and nonhistone proteins is associated with adipogenesis. The objective of the present study was to investigate whether an ethanol extract of Quercus acutissima fruit (QF) exhibits antiobesity effects through inhibition of acetylation in 3T3-L1 preadipocytes and high fat diet (HFD)-fed obese mice. We observed that QF acts as a histone acetyltransferase (HAT) inhibitor and that QF (400 µg/mL) markedly inhibits the activity of p300 and CREB-binding protein. QF (200 µg/mL) significantly attenuated lipid accumulation without apparent toxicity, which is likely attributable to a decrease in the expressions of lipogenic proteins, including fatty acid synthase, peroxisome proliferator-activated receptor gamma, sterol regulatory element-binding protein 1, and CCAAT-enhancer-binding proteins alpha that were otherwise increased by MDI (a hormonal cocktail containing methyl isobutylmethylxanthine, dexamethasone, and insulin). MDI increased the acetylation of total lysine residues in whole 3T3-L1 cell lysate, an effect that was reversed by QF treatment (200 µg/mL). To further confirm the antiobesity activity of QF, mice were fed with HFD supplemented with QF at 50 and 200 mg/kg body weight. Mice fed with HFD exhibited increased masses of body, liver, and retroperitoneal fat, an effect that was suppressed in the presence of QF supplementation. QF-mediated decreases in body weight were attributable to a decrease in the average size of lipid droplets, as well as lipid accumulation in retroperitoneal fat and the liver, respectively. QF-mediated reductions in the size of the lipid droplets in the retroperitoneal fat tissue were likely associated with decreased expression of DGAT2. Taken together, our observations suggest that QF acts as an HAT inhibitor and attenuates adipogenesis in 3T3-L1 preadipocytes, resulting in the mitigation of HFD-induced obesity.

Ethanol Extract of Capsella bursa-pastoris Improves Hepatic Steatosis Through Inhibition of Histone Acetyltransferase Activity.

Histone lysine acetylation is thought to play a role in regulating the balance between energy storage and energy expenditure. However, the epigenetic mechanisms by which food phytochemicals influence metabolic processes in the liver have not been thoroughly investigated. In this study, we investigated the effect of an ethanol extract of Capsella bursa-pastoris (ECB) on histone acetyltransferase (HAT) inhibition, and whether it could thereby attenuate lipid accumulation in vitro and in vivo. We observed that ECB inhibits HAT activity as assessed by colorimetric and autoradiography assay systems. ECB also reduced oleic acid (OA)-stimulated histone acetylation at H4K5 and H4K12 and attenuated OA-mediated lipid accumulation in HepG2 cells, in the absence of observable cytotoxicity. We then investigated these effects in vivo. Mice were fed on either a normal diet (ND) or high-fat diet (HFD) in the presence or absence of ECB supplementation. In comparison with the ND controls, the HFD mice exhibited higher body weight, liver fat, adipose tissue size, and total serum cholesterol concentrations, and these effects were significantly attenuated by ECB supplementation. Taken together, these results suggest that ECB protects against the mechanisms responsible for HFD-induced hepatic steatosis, and may involve the targeting of histone H4K acetylation.

Pinolenic Acid in Structured Triacylglycerols Exhibits Superior Intestinal Lymphatic Absorption As Compared to Pinolenic Acid in Natural Pine Nut Oil.

The positional distribution pattern of fatty acids (FAs) in the triacylglycerols (TAGs) affects intestinal absorption of these FAs. The aim of this study was to compare lymphatic absorption of pinolenic acid (PLA) present in structured pinolenic TAG (SPT) where PLA was evenly distributed on the glycerol backbone, with absorption of pine nut oil (PNO) where PLA was predominantly positioned at the sn-3 position. SPT was prepared via the nonspecific lipase-catalyzed esterification of glycerol with free FA obtained from PNO. Lymphatic absorption of PLA from PNO and from SPT was compared in a rat model of lymphatic cannulation. Significantly (P < 0.05) greater amounts of PLA were detected in lymph collected for 8 h from an emulsion containing SPT (28.5 ± 0.7% dose) than from an emulsion containing PNO (26.2 ± 0.6% dose), thereby indicating that PLA present in SPT has a greater capacity for lymphatic absorption than PLA from PNO.

Citrus junos Tanaka peel ameliorates hepatic lipid accumulation in HepG2 cells and in mice fed a high-cholesterol diet.

BACKGROUND: Citrus junos Tanaka (yuja), a yellow-coloured citrus fruit has traditionally been consumed in Korea, Japan, and China and has been found effective in preventing certain diseases. However, the inhibitory effect of yuja on hepatic lipid accumulation has not been clearly elucidated thus far. METHODS: The inhibitory effect of yuja on hepatic lipid accumulation was investigated in both cell culture and mouse models. We investigated the inhibitory effect of ethanol extract of yuja peel (YE) using HepG2 cells. We next confirmed the effect of YE in mice fed a high cholesterol diet. Animals were divided into 4 groups (n = 8): a normal diet group (ND), a high-cholesterol diet group (HC), high-cholesterol diet plus 1% YE (YL), high-cholesterol diet plus 5% YE (YH). RESULT: Seventy percent ethanolic extracts of yuja peel (YE) reduced oleic acid-induced hepatic lipid accumulation in HepG2 cells. Treatment with YE at 100, 200 µg/mL up-regulated expression levels of cholesterol metabolism-related proteins such as AMPK, ACC, PPAR-α, and CPT1 and down-regulated the expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase. The hypocholesterolemic effect of YE was further confirmed in mice fed a high-cholesterol diet. Compared to ND (normal diet) mice, HC (high-cholesterol diet) mice showed increased body weight, liver fat content, liver weight, and content of total cholesterol and low-density lipoprotein (LDL) cholesterol. On the contrary, administrations of YL (HC + 1% YE) or YH (HC + 5% YE) significantly reduced body weight, liver fat content, liver weight, total cholesterol, and LDL cholesterol compared to those of only HC fed mice group. As a result of in vitro data, protein expressions of PPAR-α and CPT1 were induced in mice fed YE diet compared to HC diet but HMGCR expression was decreased. CONCLUSIONS: Yuja peel ameliorates hepatic lipid accumulation in both cell culture and mouse models and therefore, could serve as a useful supplement for hypercholesterolemia.

Protective Effects of Black Hoof Medicinal Mushroom from Korea, Phellinus linteus (Higher Basidiomycetes), on Osteoporosis In Vitro and In Vivo.

The protective effect of Phellinus linteus (ethanol extract) against osteoporosis was investigated using the Saos-2 human osteoblast-like cell line and osteoclasts. A nontoxic concentration of Ph. linteus (10-2 to 10-8 mg mL-1) increased alkaline phosphatase (ALP) (EC 3.1.3.1) activity to a larger extent than soy did. Ph. linteus also attenuated the number and the activity of tartrate-resistant acid phosphatase-positive multinucleated osteoclasts. These results indicate that Ph. linteus likely regulated both osteoblasts and osteoclasts, contributing to the protection against osteoporosis. The protective effect of Ph. linteus was examined in ovariectomized (OVX) rats. Histological analysis indicates that Ph. linteus improved trabecular bone mass and reduced osteoclast frequency without affecting lipid droplet accumulation in the femur of OVX rats. A Ph. linteus supplementation for 12 weeks also significantly increased serum ALP activity and reduced urinary deoxypyridinoline level in OVX rats. Ultimately, we found that 12-week Ph. linteus supplementation increased the bone accumulation of minerals, including calcium, magnesium, and phosphorus. Collectively, Ph. linteus protected against osteoporosis by balancing the number of osteoblasts and osteoclasts, which was particularly associated with increased ALP activity in vitro and in vivo and mineral accumulation in bone.