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Sixteen antioxidative compounds were purified and isolated from the aerial parts of Suaeda japonica by column chromatography using Amberlite XAD-2 and octadecylsilane columns and high-performance liquid chromatography. These compounds, esculin (1), citrusin D (2), scopolin (3), cichoriin (4), isorhamnetin 3-O-rutinoside-7-O-β- D-glucopyranoside (5), 3'-methoxytaxifolin 7-O-β-D-glucopyranoside (6), (+)-lyoniresinol 3a-O-β-D-glucopyranoside (7), (2R,3R,4S)-isolariciresinol 3a-O-β-D-glucopyranoside (8), N-cis-feruloyltyramine 4-O-β-D-glucopyranoside (9), N-cis-feruloylmethoxytyramine 4-O-β-D-glucopyranoside (10), trans-icariside H1 (11), cis-icariside H1 (12), N-trans- feruloyltyramine 4-O-β-D-glucopyranoside (13), rutin (14), kaempferol-3-O-rutinoside (15), and narcissin (16), were identified for the firtst time in S. japonica. The structures of these compounds were determined by mass spectrometry and nuclear magnetic resonance spectroscopic analyses. Among the compounds, 14 showed the highest 1,1-diphenyl- 2-picrylhydrazyl free radical-scavenging activity and 8 exhibited the highest reactive oxygen species-scavenging activity in Huh7 cells.

Sterol regulatory element binding protein (SREBP) cleavage-associating protein (SCAP) is a sterol-regulated escort protein that translocates SREBPs from the endoplasmic reticulum to the Golgi apparatus, thereby activating lipid metabolism and cholesterol synthesis. Although SCAP regulates lipid metabolism in metabolic tissues, such as the liver and muscle, the effect of macrophage-specific SCAP deficiency in adipose tissue macrophages (ATMs) of patients with metabolic diseases is not completely understood.Here, we examined the function of SCAP in high-fat/high-sucrose diet (HFHS)-fed mice and investigated its role in the polarization of classical activated macrophages in adipose tissue.Macrophage-specific SCAP knockout (mKO) mice were generated through crossbreeding lysozyme 2-cre mice with SCAP floxed mice which were then fed HFHS for 12 weeks. Primary macrophages were derived from bone marrow cells and analyzed further.We found that fat accumulation and the appearance of proinflammatory M1 macrophages were both higher in HFHS-fed SCAP mKO mice relative to floxed control mice. We traced the effect to a defect in the lipopolysaccharide-mediated increase in SREBP-1a that occurs in control but not SCAP mKO mice. Mechanistically, SREBP-1a increased expression of cholesterol 25-hydroxylase transcription, resulting in an increase in the production of 25-hydroxycholesterol (25-HC), an endogenous agonist of liver X receptor alpha (LXRα) which increased expression of cholesterol efflux to limit cholesterol accumulation and M1 polarization. In the absence of SCAP mediated activation of SREBP-1a, increased M1 macrophage polarization resulted in reduced cholesterol efflux downstream from 25-HC-dependent LXRα activation.Overall, the activation of the SCAP-SREBP-1a pathway in macrophages may provide a novel therapeutic strategy that ameliorates obesity by controlling cholesterol homeostasis in ATMs.

Nonalcoholic fatty liver disease (NAFLD) affects a quarter of the global population. However, its pathogenesis is not completely understood. In our recent study, we have demonstrated that in a high-fat diet-induced liver steatosis model, the activation of SREBF1/SREBP-1c (sterol regulatory element binding transcription factor 1) directly upregulates Mir216a transcription, which inhibits CTH/CSE (cystathionase (cystathionine gamma-lyase)) expression and its function in hydrogen sulfide (H(2)S) production. Reduced H(2)S production suppresses the sulfhydration of ULK1 (unc-51 like autophagy activating kinase 1), consequently inhibiting autophagic flux and lipid droplet turnover. A single substitution mutation (C951S) in ULK1 or the silencing of CTH impairs ULK1 sulfhydration-mediated lipophagy, thereby promoting hepatic steatosis in mice. Interestingly, the sulfhydration of ULK1 increases its intrinsic kinase activity to modulate autophagy at both initiation and progression stages of autophagic catabolic flux. This study reveals that SREBF1/SREBP-1c contributes to hepatic lipid accumulation through its combined effect of increased lipid synthesis coupled with decreased lipid degradation mediated by autophagic dysregulation.

Changes in structural and functional neuroplasticity have been implicated in various neurological disorders. Sterol regulatory element-binding protein (SREBP)-1c is a critical regulatory molecule of lipid homeostasis in the brain. Recently, our findings have shown the potential involvement of SREBP-1c deficiency in the alteration of novel modulatory molecules in the hippocampus and occurrence of schizophrenia-like behaviors in mice. However, the possible underlying mechanisms, related to neuronal plasticity in the hippocampus, are yet to be elucidated. In this study, we investigated the hippocampus-dependent memory function and neuronal architecture of hippocampal neurons in SREBP-1c knockout (KO) mice. During the passive avoidance test, SREBP-1c KO mice showed memory impairment. Based on Golgi staining, the dendritic complexity, length, and branch points were significantly decreased in the apical cornu ammonis (CA) 1, CA3, and dentate gyrus (DG) subregions of the hippocampi of SREBP-1c KO mice, compared with those of wild-type (WT) mice. Additionally, significant decreases in the dendritic diameters were detected in the CA3 and DG subregions, and spine density was also significantly decreased in the apical CA3 subregion of the hippocampi of KO mice, compared with that of WT mice. Alterations in the proportions of stubby and thin-shaped dendritic spines were observed in the apical subcompartments of CA1 and CA3 in the hippocampi of KO mice. Furthermore, the corresponding differential decreases in the levels of SREBP-1 expression in the hippocampal subregions (particularly, a significant decrease in the level in the CA3) were detected by immunofluorescence. This study suggests that the contributions of SREBP-1c to the structural plasticity of the mouse hippocampus may have underlain the behavioral alterations. These findings offer insights into the critical role of SREBP-1c in hippocampal functioning in mice.

In this study, an iridium oxide (IrO2) inverse-opal membrane-electrode assembly (inverse-opal MEA) was fabricated via the decal-transfer method for an anode in polymer-electrolyte membrane water electrolysis (PEMWE) to decrease the loading of the noble catalyst. Electrodeposition parameters including current and total number of cycles were investigated to achieve the IrO2 inverse-opal electrode. The inverse-opal MEA with ultra-low loading exhibited outstanding performance that exceeded or was comparable to that obtained in other PEMWE studies. Additionally, it exhibited higher performance and lower ohmic and charge-transfer resistance when compared with that of commercial IrO2. Furthermore, the performance corresponded to the highest mass activity reported to date since the loading in the inverse-opal MEA was ultra-low. This was because the inverse-opal structure improved electron transfer owing to the interconnected pores and increased the surface area due to high porosity, thereby leading to the enhanced utilization of the catalyst.

Lipid homeostasis is an important component of brain function, and its disturbance causes several neurological disorders, such as Huntington&rsquo, s, Alzheimer&rsquo, s, and Parkinson&rsquo, s diseases as well as mood disorders. Sterol regulatory element-binding protein-1c (SREBP-1c) is a key modulatory molecule involved in lipid homeostasis in the central nervous system. However, little is known about the biological effects of SREBP-1c in the brain. Our previous study uncovered that mice deficient in SREBP-1c exhibit schizophrenia-like behaviors. To investigate whether there are novel molecular mechanisms involved in the neurological aberrations caused by SREBP-1c deficiency, we analyzed the transcriptomes of the hippocampus of SREBP-1c knockout (KO) mice and wild-type mice. We found seven differentially expressed genes (three up-regulated and four down-regulated genes) in the hippocampus of SREBP-1c KO mice. For further verification, we selected the three most significantly changed genes: glucagon-like peptide 2 receptors (GLP2R) involved in hippocampal neurogenesis and neuroplasticity as well as in cognitive impairments, necdin (NDN) which is related to neuronal death and neurodevelopmental disorders, and Erb-B2 receptor tyrosine kinase 4 (ERBB4) which is a receptor for schizophrenia-linked protein, neuregulin-1. The protein levels of GLP2R and NDN were considerably decreased, but the level of ERBB4 was significantly increased in the hippocampus of SREBP-1c KO mice. However, further confirmation is warranted to establish the translatability of these findings from this rodent model into human patients. We suggest that these data provide novel molecular evidence for the modulatory role of SREBP-1c in the mouse hippocampus.

Macroautophagy/autophagy, a self-degradative process, regulates metabolic homeostasis in response to various stress conditions and is a therapeutic target for nonalcoholic fatty liver disease. We found that autophagic activity was inhibited as a result of a significant reduction in the expression of autophagy-related genes such as Ulk1 in a mouse model and patients with fatty liver. This downregulation was caused by increased Mir214-3p levels and decreased Hnf4a/Hnf4α mRNA levels in hepatocytes. Mir214-3p suppressed Ulk1 expression through direct binding at a 3′ untranslated region sequence. Hnf4a directly activated transcription of Ulk1. We investigated lipid accumulation and the expression of autophagy-related genes in the livers of mice treated with anti-Mir214-3p. Hepatic steatosis was alleviated, and Ulk1 mRNA levels were significantly increased by locked nucleic acid-mediated Mir214-3p silencing. Additionally, autophagosome formation and MAP1LC3/LC3-II protein levels were increased, indicating an increase in autophagic activity. Interestingly, suppression of Mir214-3p did not ameliorate fatty liver under Ulk1 suppression, suggesting that reduced Mir214-3p levels mitigate hepatic steatosis through upregulation of Ulk1. These results demonstrate that inhibition of Mir214-3p expression ameliorated fatty liver disease through increased autophagic activity by increasing the expression of Ulk1. Thus, Mir214-3p is a potential therapeutic target for nonalcoholic fatty disease. Abbreviations: AMPK: adenosine monophosphate-activated protein kinase; ATG: autophagy-related; ChIP: chromatin immunoprecipitation; CTSB: cathepsin B; CTSL: cathepsin L; CQ: chloroquine; HFD: high-fat diet; HNF4A: hepatocyte nuclear factor 4, alpha; IF: immunofluorescence; IHC: immunohistochemistry; LDs: lipid droplets; Leup: leupeptin; LFD: low-fat diet; LNA: locked nucleic acid; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; miRNA: microRNA; MTOR: mechanistic target of rapamycin kinase; NAFLD: non-alcoholic fatty liver disease; NASH: non-alcoholic steatohepatitis; PCR: polymerase chain reaction; TEM: transmission electron microscopy; TF: transcription factor; TLDA: TaqMan low-density array; ULK1: unc-51 like kinase 1; UTR: untranslated region

A metabolic imbalance between lipid synthesis and degradation can lead to hepatic lipid accumulation, a characteristic of patients with non-alcoholic fatty liver disease (NAFLD). Here, we report that high-fat-diet-induced sterol regulatory element-binding protein (SREBP)-1c, a key transcription factor that regulates lipid biosynthesis, impairs autophagic lipid catabolism via altered H2S signaling. SREBP-1c reduced cystathionine gamma-lyase (CSE) via miR-216a, which in turn decreased hepatic H2S levels and sulfhydration-dependent activation of Unc-51-like autophagy-activating kinase 1 (ULK1). Furthermore, Cys951Ser mutation of ULK1 decreased autolysosome formation and promoted hepatic lipid accumulation in mice, suggesting that the loss of ULK1 sulfhydration was directly associated with the pathogenesis of NAFLD. Moreover, silencing of CSE in SREBP-1c knockout mice increased liver triglycerides, confirming the connection between CSE, autophagy, and SREBP-1c. Overall, our results uncover a 2-fold mechanism for SREBP-1c-driven hepatic lipid accumulation through reciprocal activation and inhibition of hepatic lipid biosynthesis and degradation, respectively.

A Glu–Phe (EF) was isolated from onion (Allium cepa L. cv. Sunpower). The chemical structure of EF was determined by nuclear magnetic resonance and electrospray ionization–mass (ESI−MS) spectroscopy. We showed that EF reduced lipid accumulation in mouse hepatocytes by inhibiting the expression of sterol regulatory element-binding protein-1c (SREBP–1c) and its lipogenic target genes. We also found that AMP-activated protein kinase (AMPK) was required for the inhibitory effect of EF on lipid accumulation in mouse hepatocytes. Furthermore, EF was qualified in nine onion cultivars by selective multiple reaction-monitoring detection of liquid chromatography–ESI−MS. These results suggest that EF could contribute to the beneficial effect of onion supplement in maintaining hepatic lipid homeostasis.

// Da-Hye Go 1, * , Yu Geon Lee 1, * , Da-Hye Lee 2, 3, * , Jin-A Kim 1 , In-Hwa Jo 1 , Yeon Soo Han 4 , Yong Hun Jo 4 , Kwang-Youn Kim 5 , Young-Kyo Seo 5 , Jae-Hak Moon 6 , Chang Hwa Jung 2, 3 and Tae-Il Jeon 1 1 Department of Animal Science, College of Agriculture & Life Science, Chonnam National University, Gwangju, Republic of Korea 2 Research Group of Metabolic Mechanism, Korea Food Research Institute, Seongnam, Republic of Korea 3 Department of Food Biotechnology, Korea University of Science and Technology, Seongnam, Republic of Korea 4 Division of Plant Biotechnology, Institute of Environmentally-Friendly Agriculture (IEFA), College of Agriculture and Life Sciences, Chonnam National University, Gwangju, Republic of Korea 5 Department of Integrated Oncological Therapies, IRCCS AOU, San Martino, IST, Largo Rosanna Benzi, Genova, Italy 6 Department of Food Science & Technology, Chonnam National University, Gwangju, Republic of Korea * These authors have contributed equally to this work Correspondence to: Tae-Il Jeon, email: tjeon@jnu.ac.kr Chang Hwa Jung, email: chjung@kfri.re.kr Keywords: autophagy, cell death, ER stress, hepatocellular carcinoma, urushiol Received: January 25, 2017 Accepted: April 17, 2017 Published: May 09, 2017 ABSTRACT The natural, phenolic lipid urushiol exhibits both antioxidant and anticancer activities; however, its biological activity on hepatocellular carcinoma (HCC) has not been previously investigated. Here, we demonstrate that an urushiol derivative, 3-decylcatechol (DC), induces human HCC Huh7 cell death by induction of autophagy. DC initiates the autophagic process by activation of the mammalian target of rapamycin signaling pathway via Unc-51-like autophagy activating kinase 1, leading to autophagosome formation. The autophagy inhibitor, chloroquine, suppressed autolysosome formation and cell death induction by DC, indicating an autophagic cell death. Interestingly, DC also activated the endoplasmic reticulum (ER) stress response that promotes autophagy via p62 transcriptional activation involving the inositol-requiring enzyme 1α/c-Jun N-terminal kinase/c-jun pathway. We also show that cytosolic calcium mobilization is necessary for the ER stress response and autophagy induction by DC. These findings reveal a novel mechanism by which this urushiol derivative induces autophagic cell death in HCC.

Although SREBP-1c regulates key enzymes required for hepatic de novo lipogenesis, the mechanisms underlying transcriptional regulation of SREBP-1c in pathogenesis of alcoholic fatty liver is still incompletely understood. In this study, we investigated the role of ERRγ in alcohol-mediated hepatic lipogenesis and examined the possibility to ameliorate alcoholic fatty liver through its inverse agonist. Hepatic ERRγ and SREBP-1c expression was increased by alcohol-mediated activation of CB1 receptor signaling. Deletion and mutation analyses of the Srebp-1c gene promoter showed that ERRγ directly regulates Srebp-1c gene transcription via binding to an ERR-response element. Overexpression of ERRγ significantly induced SREBP-1c expression and fat accumulation in liver of mice, which were blocked in Srebp-1c-knockout hepatocytes. Conversely, liver-specific ablation of ERRγ gene expression attenuated alcohol-mediated induction of SREBP-1c expression. Finally, an ERRγ inverse agonist, GSK5182, significantly ameliorates fatty liver disease in chronically alcohol-fed mice through inhibition of SREBP-1c-mediated fat accumulation. ERRγ mediates alcohol-induced hepatic lipogenesis by upregulating SREBP-1c expression, which can be blunted by the inverse agonist for ERRγ, which may be an attractive therapeutic strategy for the treatment of alcoholic fatty liver disease in human.

We previously reported that 3-pentylcatechol (PC), a synthetic non-allergenic urushiol derivative, inhibited the growth of Helicobacter pylori in an in vitro assay using nutrient agar and broth. In this study, we aimed to investigate the in vivo antimicrobial activity of PC against H. pylori growing in the stomach mucous membrane. Four-week-old male C57BL/6 mice (n = 4) were orally inoculated with H. pylori Sydney Strain-1 (SS-1) for 8 weeks. Thereafter, the mice received PC (1, 5, and 15 mg/kg) and triple therapy (omeprazole, 0.7 mg/kg, metronidazole, 16.7 mg/kg, clarithromycin, 16.7 mg/kg, reference groups) once daily for 10 days. Infiltration of inflammatory cells in gastric tissue was greater in the H. pylori-infected group compared with the control group and lower in both the triple therapy- and PC-treated groups. In addition, upregulation of cytokine mRNA was reversed after infection, upon administration of triple therapy and PC. Interestingly, PC was more effective than triple therapy at all doses, even at 1/15th the dose of triple therapy. In addition, PC demonstrated synergism with triple therapy, even at low concentrations. The results suggest that PC may be more effective against H. pylori than established antibiotics.

Hepatocellular carcinoma (HCC) accounts for approximately 90% of all cases of primary liver cancer; it is the third most frequent cause of cancer-related death worldwide. In early-stage disease, surgical resection and liver transplantation are considered curative treatments. However, the majority of HCC patients present with advanced-stage disease that is treated using palliative systemic therapy. Since HCC is heterogeneous owing to its multiple etiologies, various risk factors, and inherent resistance to chemotherapy, the development of an effective systemic treatment strategy for HCC remains a considerable challenge. Autophagy is a lysosome-dependent catabolic degradation pathway that is essential for maintaining cellular energy homeostasis. Autophagy dysfunction is closely linked with the pathogenesis of various cancers; therefore, the discovery of small molecules that can modulate autophagy has attracted considerable interest in the development of a systemic treatment strategy for advanced HCC. Here, we reviewed the roles of autophagy in HCC and the recent advances regarding small molecules that target autophagy regulatory mechanisms.

A Glu–Phe (EF) was isolated from onion (Allium cepa L. cv. Sunpower). The chemical structure of EF was determined by nuclear magnetic resonance and electrospray ionization–mass (ESI−MS) spectroscopy. We showed that EF reduced lipid accumulation in mouse hepatocytes by inhibiting the expression of sterol regulatory element-binding protein-1c (SREBP–1c) and its lipogenic target genes. We also found that AMP-activated protein kinase (AMPK) was required for the inhibitory effect of EF on lipid accumulation in mouse hepatocytes. Furthermore, EF was qualified in nine onion cultivars by selective multiple reaction-monitoring detection of liquid chromatography–ESI−MS. These results suggest that EF could contribute to the beneficial effect of onion supplement in maintaining hepatic lipid homeostasis. EF from onion decreases the expression of SREBP-1c and its lipogenic target genes through activating AMP-AMPK, thereby attenuating lipid accumulation in mouse hepatocytes.

Dysregulated autophagy is associated with steatosis and non-alcoholic fatty liver disease (NAFLD), however the mechanisms connecting them remain poorly understand. Here, we show that co-administration of lovastatin and ezetimibe (L/E) significantly reverses hepatic triglyceride accumulation concomitant with an increase in SREBP-2 driven autophagy in mice fed a high-fat diet (HFD). We further show that the statin mediated increase in SREBP-2 directly activates expression of patatin-like phospholipase domain-containing enzyme 8 (PNPLA8) gene, and PNPLA8 associates with autophagosomes and is associated with a decrease in cellular triglyceride. Moreover, we show that over-expression of PNPLA8 dramatically decreases hepatic steatosis through increased autophagy in hepatocytes of HFD-fed mice. Live-cell imaging analyses also reveal that PNPLA8 dynamically interacts with LC3 and we suggest that the SREBP-2/PNPLA8 axis represents a novel regulatory mechanism for lipid homeostasis. These data provide a possible mechanism for the reported beneficial effects of statins for decreasing hepatic triglyceride levels in NAFLD patients.

Dysregulated autophagy is associated with steatosis and non-alcoholic fatty liver disease (NAFLD), however the mechanisms connecting them remain poorly understand. Here, we show that co-administration of lovastatin and ezetimibe (L/E) significantly reverses hepatic triglyceride accumulation concomitant with an increase in SREBP-2 driven autophagy in mice fed a high-fat diet (HFD). We further show that the statin mediated increase in SREBP-2 directly activates expression of patatin-like phospholipase domain-containing enzyme 8 (PNPLA8) gene, and PNPLA8 associates with autophagosomes and is associated with a decrease in cellular triglyceride. Moreover, we show that over-expression of PNPLA8 dramatically decreases hepatic steatosis through increased autophagy in hepatocytes of HFD-fed mice. Live-cell imaging analyses also reveal that PNPLA8 dynamically interacts with LC3 and we suggest that the SREBP-2/PNPLA8 axis represents a novel regulatory mechanism for lipid homeostasis. These data provide a possible mechanism for the reported beneficial effects of statins for decreasing hepatic triglyceride levels in NAFLD patients.

Scope Obesity and diabetes are major public health problems and are emerging as pandemics. Considerable evidence suggests that pear fruit consumption is associated with a lower risk of obesity-related complications. Thus, the present study is conducted to investigate the therapeutic potential of pear extract (PE) for reversing obesity and associated metabolic complications in high-fat diet-induced obese mice. Methods and results Obesity is induced in male C57BL/6 mice fed a high-fat diet for 11 weeks. After the first 6 weeks on the diet, obese mice are administered vehicle or PE for 5 weeks. PE treatment decreases body weight gain, expands white adipose tissue (WAT), and causes hepatic steatosis in obese mice, as well as inhibits adipogenesis and lipogenesis. Impaired glucose tolerance and insulin resistance are improved by PE. In addition, PE reduces macrophage infiltration and expression of pro-inflammatory genes and deactivates mitogen-activated protein kinases in WAT. Finally, malaxinic acid is identified as an active component responsible for the anti-obesity effects of PE in mice. Conclusion The results demonstrate that PE supplementation ameliorates diet-induced obesity and associated metabolic complications and suggest the health-beneficial effects of both pear fruits and malaxinic acid in counteracting these diseases.

Objective To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate (EtOAc) extract of Phellinus linteus grown on germinated brown rice (PB). Methods EtOAc extract of PB was partitioned with n-hexane, EtOAc, and water-saturated n-butanol. Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR, respectively. Cytotoxicity against HT-29 cells was tested by SRB assay. Results The n-hexane layer obtained after solvent fractionation of PB EtOAc extracts showed a potent anticancer activity against the HT-29 cell line. Atractylenolide I, a eudesmane-type sesquiterpene lactone, a major anticancer substance of PB, was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC. This structure was elucidated by one- and two-dimensional NMR spectroscopic data. Atractylenolide I has not been reported in mushrooms or rice as of yet. The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells. Conclusions Atractylenolide I might contribute to the anticancer effect of PB.

Schizophrenia is a hereditary disease that approximately 1% of the worldwide population develops. Many studies have investigated possible underlying genes related to schizophrenia. Recently, clinical studies suggested sterol regulatory element-binding protein (SREBP) as a susceptibility gene in patients with schizophrenia. SREBP controls cellular lipid homeostasis by three isoforms: SREBP-1a, SREBP-1c and SREBP-2. This study used SREBP-1c knockout (KO) mice to examine whether a deficiency in SREBP-1c would affect their emotional and psychiatric behaviors. Altered mRNA expression in genes downstream from SREBP-1c was confirmed in the brains of SREBP-1c KO mice. Schizophrenia-like behavior, including hyperactivity during the dark phase, depressive-like behavior, aggressive behavior and deficits in social interaction and prepulse inhibition, was observed in SREBP-1c KO mice. Furthermore, increased volume of the lateral ventricle was detected in SREBP-1c KO mice. The mRNA levels of several γ-aminobutyric acid (GABA)-receptor subtypes and/or glutamic acid decarboxylase 65/67 decreased in the hippocampus and medial prefrontal cortex of SREBP-1c KO mice. Thus, SREBP-1c deficiency may contribute to enlargement of the lateral ventricle and development of schizophrenia-like behaviors and be associated with altered GABAergic transmission.

Sirtuin 1 (SIRT1) plays a critical role in the maintenance of metabolic homeostasis and promotes fat mobilization in white adipose tissue. However, regulation of SIRT1 during adipogenesis, particularly through microRNAs, remains unclear. We observed that miR-146b expression was markedly increased during adipogenesis in 3T3-L1 cells. Differentiation of 3T3-L1 was induced by overexpression of miR-146b. Conversely, inhibition of miR-146b decreased adipocyte differentiation. Bioinformatics-based studies suggested that SIRT1 is a target of miR-146b. Further analysis confirmed that SIRT1 was negatively regulated by miR-146b. We also observed that miR-146b bound directly to the 3′-untranslated region of SIRT1 and inhibited adipogenesis through SIRT1 downregulation. The miR-146b/SIRT1 axis mediates adipogenesis through increased acetylation of forkhead box O1 (FOXO1). Expression of miR-146b was increased and SIRT1 mRNA subsequently decreased in the adipose tissues of diet-induced and genetically obese mice. Furthermore, in vivo knockdown of miR-146b by a locked nucleic acid miR-146b antagomir significantly reduced body weight and fat volume in accordance with upregulation of SIRT1 and subsequent acetylation of FOXO1. Therefore, the miR-146b/SIRT1 pathway could be a potential target for obesity prevention and treatment.

Adipose tissue development and function play a critical role in the regulation of energy balance, lipid metabolism, and the pathophysiology of metabolic syndromes. Although the effect of zinc ascorbate supplementation in diabetes or glycemic control is known in humans, the underlying mechanism is not well described. Here, we investigated the effect of a zinc-chelated vitamin C (ZnC) compound on the adipogenic differentiation of 3T3-L1 preadipocytes. Treatment with ZnC for 8 d significantly promoted adipogenesis, which was characterized by increased glycerol-3-phosphate dehydrogenase activity and intracellular lipid accumulation in 3T3-L1 cells. Meanwhile, ZnC induced a pronounced up-regulation of the expression of glucose transporter type 4 (GLUT4) and the adipocyte- specific gene adipocyte protein 2 (aP2). Analysis of mRNA and protein levels further showed that ZnC increased the sequential expression of peroxisome proliferator-activated receptor gamma (PPAR) and CCAAT/enhancer-binding protein alpha (C/EBP), the key transcription factors of adipogenesis. These results indicate that ZnC could promote adipogenesis through PPAR and C/EBP, which act synergistically for the expression of aP2 and GLUT4, leading to the generation of insulin-responsive adipocytes and can thereby be useful as a novel therapeutic agent for the management of diabetes and related metabolic disorders. (Key Words: Zinc-chelated Vitamin C, Adipogenesis, PPAR, C/EBP, GLUT4, 3T3-L1)

Scope Lipid homeostasis in vertebrates is regulated at many levels including synthesis, degradation, and distribution. MicroRNAs (miRNAs) are key regulators of lipid homeostasis. The use of phytochemicals to target miRNA (miR) could provide new therapeutic approaches to human diseases. Thus, we investigated the regulation of lipid metabolism by the flavonoid fisetin during experimental analysis of hepatic miRs in mice. Methods and results Mice were separated into three groups. One group was maintained on the normal diet and the other two groups were fed either a high-fat (HF) diet or HF supplemented with fisetin. We found that fisetin lowered hepatic fat accumulation in HF mice and reversed abnormal expressions of lipid metabolism genes. The co-expression of miR-378 and its host gene PGC-1β was significantly induced by HF, whereas fisetin prevented the induction of both genes. We also identified nuclear respiratory factor-1 (NRF-1), a critical regulator of the mitochondrial function, as a direct target of miR-378. Conclusion Dietary fisetin protects against hepatosteatosis in association with modulation of lipid metabolism genes and miR-378 in mice. These observations suggest that the use of fisetin to target miRs could be an effective prevention or intervention against metabolic diseases.

Fourteen compounds were isolated from 60% ethanol extracts of immature pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit using Amberlite XAD-2 column HPLC with guided DPPH radical scavenging assay. Based on MS and NMR analysis, the isolated compounds were identified as 5-O-trans-caffeoyl quinic acid methyl ester (1), malaxinic acid (2), 5-O-trans-p-coumaroyl quinic acid methyl ester (3), 5-O-cis-p-coumaroyl quinic acid methyl ester (4), 5-O-trans-p-coumaroyl quinic acid (5), trans-p-coumaric acid (6), methyl cis-p-coumarate (7), methyl trans-p-coumarate (8), 3,5-O-dicaffeoyl quinic acid (9), (-)-epicatechin (10), (S)-(+)-2-cis-abscisic acid (11), isorhamnetin 3-O-β-d-galacto-pyranoside (12), isorhamnetin-3-O-β-d-glucopyranoside (13), and isorhamnetin 3-O-α-l-rhamnopyranosyl (1→6)-O-β-d-glucopyranoside (14). Six compounds (1, 2, 6, 9, 10, and 13) were identified previously, but other compounds (3–5, 7, 8, 11, 12, and 14) were isolated for the first time from pear.

정보화 사회의 도래로 아카이브 기관은 대국민 서비스의 일환으로 디지털 기술을 도입하여 보존과 전시에 활용하기에 이르렀다. 본 연구의 목적은 급변하는 기술의 발전으로 인하여 아카이브 전시에 다양한 디지털 기술을 사용하는 것에 대한 필요성을 고찰하는 것이다. 이를 위해 아카이브와 디 지털 전시의 개념과 유형을 살펴보고, 아카이브에 디지털 전 시방법을 사용할 때 그 활용도를 조사하였다. 또한 구체적인 기록물관 리기관의 디지털 전시사례를 조사하였다. 아카이브자료를 웹 페이지를 통하여 전시했을 때 가장 큰 장점은 기록물이 가지는 본연의 정보 제공의 기능과 더불어 하이퍼링크 기술을 통한 정보의 무한 확장성을 들 수 있다. 디지털전시의 방법으로 가상현실은 평면적인 아카이브에 입체감과 현실감을 넣어 이 용자의 흥미와 관심을 불러일으킨다. 또한 스토리텔링은 온라인상에 이용자와의 커뮤니케이션의 장을 만들어 서로 상호작용을 하며 이 과정까지도 스토리에 반영되어 새로운 콘텐츠로 탄 생된다. 이러한 일련의 기능들이 아카이브에 대한 관심과 흥 미를 높여 이용자들의 정보의 공유, 참여를 가져오고, 더불어 디지털 전시를 통한 새로운 콘텐츠 자원은 문화 자원과 관광 자원으로 지역사회와 기관을 홍보하므로 아카이브 전시에 다양한 디지털 기술을 사용하는 것은 그 의의가 있다.주제어: 아카이브, 디지털 전시, 스토리텔링, 가상현실(VR), 커뮤니케이션, 콘텐츠 자원

The chemical conversion pattern of salvianolic acid B (Sal B) in aqueous solution under different boiling conditions was compared. When the duration of boiling was varied, without varying temperature or pressure, the content of chemically converted compounds (CCCs) was mostly increased over time. In addition, under different conditions of temperature and pressure with the same boiling time, the content of a few compounds increased with increasing temperature and pressure. These results confirmed that high temperatures and pressures in boiling alter the final composition of CCCs of Sal B. Therefore, it was suggested that the boiling conditions (time, temperature, and pressure) may be responsible for alteration of biological activities of the compounds. Our investigation of the chemical conversion of compounds contained in foods and medicinal herbs may provide important information in clarifying the biological activity of Sal B containing foods and medicinal herbs.

Numerous medicinal plants and their derivatives have been reported to prevent obesity and related diseases. Although Syzygium aromaticum has traditionally been used as an anodyne, carminative and anthelmintic in Asian countries, its potential in the prevention and treatment of obesity has not yet been explored. Therefore, the present study investigated the anti-obesity effect of S. aromaticum ethanol extract (SAE) both in vitro and in vivo. To evaluate the anti-obesity potential of SAE in vitro, the effect of SAE treatment on adipocyte differentiation in 3T3-L1 cells was investigated. To evaluate its potential in vivo, mice were assigned to three groups: a group fed the American Institute of Nutrition AIN-76A diet (normal group), an experimental group fed a high-fat diet (HFD group) and an experimental group fed an HFD supplemented with 0.5% (w/w) SAE (HFD + SAE group). After 9 weeks of feeding, the body weight; white adipose tissue (WAT) mass; serum triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL) cholesterol, glucose, insulin and leptin; hepatic lipid accumulation; and levels of lipid metabolism-related genes in the liver and WAT were measured. In vitro investigation of the effect of SAE treatment on 3T3-L1 cells revealed that it had efficiently inhibited the conversion of cells into adipocytes in a dose-dependent manner. In vivo investigation revealed that SAE supplementation had significantly decreased HFD-induced increases in the body weight, liver weight, WAT mass, and serum TG, TC, lipid, glucose, insulin and leptin levels. Consistent with its effects on liver weight and WAT mass, SAE supplementation was found to have suppressed the expression of lipid metabolism-related proteins, including SREBP-1, FAS, CD36 and PPARγ in the liver and WAT, in addition to downregulating mRNA levels of transcription factors including Srebp and Pparg. SAE inhibits fat accumulation in HFD-fed mice via the suppression of transcription factors integral to adipogenesis and lipogenesis, suggesting its potential in preventing obesity.

To understand the molecular mechanisms underlying the influence of quercetin on the physiological effects of hyperlipidemia, we investigated its role in the prevention of high-fat diet (HFD)-induced obesity and found that it regulated hepatic gene expression related to lipid metabolism. Quercetin supplementation in mice significantly reduced the HFD-induced gains in body weight, liver weight, and white adipose tissue weight compared with the mice fed only with HFD. It also significantly reduced HFD-induced increases in serum lipids, including cholesterol, triglyceride, and thiobarbituric acid-reactive substance (TBARS). Consistent with the reduced liver weight and white adipose tissue weight, hepatic lipid accumulation and the size of lipid droplets in the epididymal fat pads were also reduced by quercetin supplementation. To further investigate how quercetin may reduce obesity, we analyzed lipid metabolism-related genes in the liver. Quercetin supplementation altered expression profiles of several lipid metabolism-related genes, including Fnta, Pon1, Pparg, Aldh1b1, Apoa4, Abcg5, Gpam, Acaca, Cd36, Fdft1, and Fasn, relative to those in HFD control mice. The expression patterns of these genes observed by quantitative reverse transcriptase-polymerase chain reaction were confirmed by immunoblot assays. Collectively, our results indicate that quercetin prevents HFD-induced obesity in C57B1/6 mice, and its anti-obesity effects may be related to the regulation of lipogenesis at the level of transcription. Copyright © 2012 John Wiley & Sons, Ltd.

MicroRNAs (miRNAs) have recently emerged as a novel class of epigenetic regulators of gene expression. They are systemically involved in the control of lipid metabolism through a complex interactive mechanism that involves gene regulatory networks. Hence, they can contribute to defective lipid metabolism and metabolic diseases. Here, we review recent advances in the roles of lipid-sensing transcription factors in regulating miRNA gene networks, as well as miRNA expression and function in the regulation of cholesterol metabolism. This article is part of a Special Issue entitled: MicroRNAs and lipid/energy metabolism and related diseases edited by Carlos Fernandez-Hernando and Yajaira Suarez.

T2Rs (bitter taste-sensing type 2 receptors) are expressed in the oral cavity to prevent ingestion of dietary toxins through taste avoidance. They are also expressed in other cell types, including gut enteroendocrine cells, where their physiological role is enigmatic. Previously, we proposed that T2R-dependent CCK (cholecystokinin) secretion from enteroendocrine cells limits absorption of dietary toxins, but an active mechanism was lacking. In the present study we show that T2R signalling activates ABCB1 (ATP-binding cassette B1) in intestinal cells through a CCK signalling mechanism. PTC (phenylthiocarbamide), an agonist for the T2R38 bitter receptor, increased ABCB1 expression in both intestinal cells and mouse intestine. PTC induction of ABCB1 was decreased by either T2R38 siRNA (small interfering RNA) or treatment with YM022, a gastrin receptor antagonist. Thus gut ABCB1 is regulated through signalling by CCK/gastrin released in response to PTC stimulation of T2R38 on enteroendocrine cells. We also show that PTC increases the efflux activity of ABCB1, suggesting that T2R signalling limits the absorption of bitter tasting/toxic substances through modulation of gut efflux membrane transporters.

SummarySterol regulatory element-binding proteins (SREBPs) are key transcriptional regulators of lipid metabolism. To define functional differences between the three mammalian SREBPs we used genome-wide ChIP-seq with isoform-specific antibodies and chromatin from select tissues of mice challenged with different dietary conditions that enrich for specific SREBPs. We show that hepatic SREBP-2 binds preferentially to two different gene-proximal motifs. A Gene Ontology (GO) analysis suggests SREBP-2 targets lipid metabolic processes as expected, but apoptosis and autophagy gene categories were also enriched. We show that SREBP-2 directly activates autophagy genes during cell-sterol depletion, conditions known to induce both autophagy and nuclear SREBP-2 levels. Additionally, SREBP-2 knockdown during nutrient depletion decreased autophagosome formation and lipid droplet association of the autophagosome targeting protein LC3. Thus, the lipid droplet could be viewed as a third source of cellular cholesterol, which along with sterol synthesis and uptake, is also regulated by SREBP-2.

We compared the immunomodulating effects of Phellinus linteus (PL), germinated brown rice (BR) and P. linteus grown on germinated brown rice (PB) on IgE production in murine mesenteric lymph node (MLN) lymphocytes. All extracts decreased IgE concentrations by 43--65% compared to control mice in both serum and MLN lymphocytes. In addition, PL and PB increased the proportion of CD4(+) T cells by 9% and 12% in MLN lymphocytes. IFN-gamma concentration, Th1 cytokine, was significantly increased by 44--67%, whereas IL-4 and IL-10 concentrations, Th2 cytokine, significantly decreased by 30--60% in the three treated groups compared to control group. These results suggest that PB suppresses IgE production through the modulation of Th1/Th2 balance to down-regulate Th2 response in MLN lymphocytes, even though a synergistic effect of PB was not found.

Extracts of Phellinus linteus (EPB), grown on germinated brown rice, protected rats from liver injury induced by carbon tetrachloride (CCl4). Peroxidation products in the liver were decreased to 10% by EPB. Catalase and superoxide dismutase activities were significantly decreased to 55% and 39% by CCl4 administration, but EPB blocked this effect, resulting in enzyme activities at control levels. Expression of cytochrome P450 2E1 (CYP2E1) protein was significantly decreased to 88% in CCl4-treated rats but remained at control levels when EPB was also administered. EPB did not affect the altered fatty acid composition induced by CCl4. The hepatoprotective effect of EPB may be mediated by EPB's prevention of CCl4-induced CYP2E1 degradation.

We determined in vitro radical scavenging activity of persimmon seed extract (PSE) and grape seed extract (GSE), and quantified total tannin concentrations of each extract. It has been found that both PSE and GSE have radical scavenging activities, and total tannin concentration of PSE was significantly higher than GSE ( p p in vitro, and inhibited lipid peroxidation in vivo .

Although Alpinia officinarum has been used in traditional medicine for the treatment of several conditions, such as abdominal pain, emesis, diarrhea, impaired renal function, and dysentery, little is known about its function in obesity. In this study, we investigated the antiobesity effect of A. officinarum ethanol extract (AOE) on lipid accumulation in 3T3-L1 cells and obesity in mice fed a high-fat diet (HFD). AOE dose-dependently suppressed lipid accumulation during differentiation of 3T3-L1 preadipocytes by downregulating CCAAT enhancer binding protein α (C/EBPα), sterol regulatory element binding protein-1 (SREBP-1), and peroxisome proliferator-activated receptor-γ (PPAR-γ) genes. Galangin, a major component of A. officinarum, had antiadipogenic effects in 3T3-L1 cells. AOE supplementation in mice fed a HFD revealed that AOE significantly decreased HFD-induced increases in body, liver, and white adipose tissue weights and decreased serum insulin and leptin levels. To elucidate the inhibitory mechanism of AOE in obesity, lipid metabolism-related genes were identified. AOE efficiently suppressed protein expressions of C/EBPα, fatty acid synthase, SREBP-1, and PPAR-γ in the liver and adipose tissue. The protein expression patterns, observed by immunoblot, were confirmed by quantitative real-time polymerase chain reaction. Collectively, these results suggest that AOE prevents obesity by suppressing adipogenic and lipogenic genes. AOE has potential for use as an antiobesity therapeutic agent that can function by regulating lipid metabolism.

Fisetin, a flavonol present in vegetables and fruits, possesses antioxidative and anti-inflammatory properties. In this study, we have demonstrated that fisetin prevents diet-induced obesity through regulation of the signaling of mammalian target of rapamycin complex 1 (mTORC1), a central mediator of cellular growth, cellular proliferation and lipid biosynthesis. To evaluate whether fisetin regulates mTORC1 signaling, we investigated the phosphorylation and kinase activity of the 70-kDa ribosomal protein S6 kinase 1 (S6K1) and mTORC1 in 3T3-L1 preadipocytes. Fisetin treatment of preadipocytes reduced the phosphorylation of S6K1 and mTORC1 in a time- and concentration-dependent manner. To further our understanding of how fisetin negatively regulates mTORC1 signaling, we analyzed the phosphorylation of S6K1, mTOR and Akt in fisetin-treated TSC2-knockdown cells. The results suggested that fisetin treatment inhibits mTORC1 activity in an Akt-dependent manner. Recent studies have shown that adipocyte differentiation is dependent on mTORC1 activity. Fisetin treatment inhibited adipocyte differentiation, consistent with the negative effect of fisetin on mTOR. The inhibitory effect of fisetin on adipogenesis is dependent of mTOR activity, suggesting that fisetin inhibits adipogenesis and the accumulation of intracellular triglycerides during adipocyte differentiation by targeting mTORC1 signaling. Fisetin supplementation in mice fed a high-fat diet (HFD) significantly attenuated HFD-induced increases in body weight and white adipose tissue. We also observed that fisetin efficiently suppressed the phosphorylation of Akt, S6K1 and mTORC1 in adipose tissue. Collectively, these results suggest that inhibition of mTORC1 signaling by fisetin prevents adipocyte differentiation of 3T3-L1 preadipocytes and obesity in HFD-fed mice. Therefore, fisetin may be a useful phytochemical agent for attenuating diet-induced obesity.

To understand the molecular mechanisms underlying the influence of quercetin on the physiological effects of hyperlipidemia, we investigated its role in the prevention of high-fat diet (HFD)-induced obesity and found that it regulated hepatic gene expression related to lipid metabolism. Quercetin supplementation in mice significantly reduced the HFD-induced gains in body weight, liver weight, and white adipose tissue weight compared with the mice fed only with HFD. It also significantly reduced HFD-induced increases in serum lipids, including cholesterol, triglyceride, and thiobarbituric acid-reactive substance (TBARS). Consistent with the reduced liver weight and white adipose tissue weight, hepatic lipid accumulation and the size of lipid droplets in the epididymal fat pads were also reduced by quercetin supplementation. To further investigate how quercetin may reduce obesity, we analyzed lipid metabolism-related genes in the liver. Quercetin supplementation altered expression profiles of several lipid metabolism-related genes, including Fnta, Pon1, Pparg, Aldh1b1, Apoa4, Abcg5, Gpam, Acaca, Cd36, Fdft1, and Fasn, relative to those in HFD control mice. The expression patterns of these genes observed by quantitative reverse transcriptase-polymerase chain reaction were confirmed by immunoblot assays. Collectively, our results indicate that quercetin prevents HFD-induced obesity in C57B1/6 mice, and its anti-obesity effects may be related to the regulation of lipogenesis at the level of transcription.

We used mouse hepatic chromatin enriched with an FXR antibody and chromatin immunoprecipitation-sequencing (ChIP-seq) to evaluate FXR binding on a genome-wide scale. This identified 1656 FXR-binding sites and 10% were located within 2 kb of a transcription start site which is much higher than predicted by random occurrence. A motif search uncovered a canonical nuclear receptor IR-1 site, consistent with in vitro DNA-binding studies reported previously. A separate nuclear receptor half-site for monomeric receptors such as LRH-1 was co-enriched and FXR activation of four newly identified promoters was significantly augmented by an LRH-1 expression vector in a co-transfection assay. There were 1038 genes located within 20 kb of a peak and a gene set enrichment analysis showed that genes identified by our ChIP-seq analysis are highly correlated with genes activated by an FXR-VP16 adenovirus in primary mouse hepatocytes providing functional relevance to the genome-wide binding study. Gene Ontology analysis showed FXR-binding sites close to many genes in lipid, fatty acid and steroid metabolism. Other broad gene clusters related to metabolism, transport, signaling and glycolysis were also significantly enriched. Thus, FXR may have a much wider role in cellular metabolism than previously appreciated.