Methylxanthine Derivative-Rich Cacao Extract Suppresses Differentiation of Adipocytes through Downregulation of PPARγ and C/EBPs

Abstract Cacao extract (CE) consumption has beneficial effects on human health, such as lowering the risk of obesity. However, the underlying molecular mechanism for the anti-obesity effect of CE remains incompletely understood. Here, we used a 50% aqueous alcohol extract of cacao mass, which is rich in methylxanthine derivatives (about 11%) and poor in flavan-3-ols (less than 1%), and assessed the suppression effects of this extract on adipocyte differentiation to investigate the anti-obesity mechanism. CE dose-dependently decreased fat accumulation in 3T3-L1 cells without affecting cell viability. CE also dose-dependently decreased the protein and gene expression levels of two adipogenesis-related transcription factors, peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding proteins (C/EBPs). Moreover, CE decreased protein expression levels of sterol regulatory element-binding protein 1 (SREBP1) and its downstream fatty acid synthase (FAS), which was accompanied by the retained localization of SREBP1 in the cytoplasm of 3T3-L1 cells. After ICR mice were fed a diet containing 1% CE for 1 wk, their white adipose tissue weight was lower, whereas their brown adipose tissue weight was higher compared with those of control animals. Additionally, the protein expression levels of PPARγ, C/EBPs, SREBP1, and FAS in the white adipose tissue of these mice were also lower than those in control animals. In contrast, diet supplementation with CE induced higher levels of phosphorylated AMP-activated protein kinase (AMPK) and its downstream acetyl-CoA carboxylase. In conclusion, methylxanthine derivative-rich CE decreases fat accumulation in adipocytes by downregulating the expression of the adipocyte differentiation master regulators through the activation of AMPK.ArticleJournal of Nutritional Science and Vitaminology. 64(2): 151-160. (2018)journal articl

Morphological Character and Corm Quality of Somatic Hybrid of Taro (Colocasia esculenta Schott)

　Morphological character and quality of corm in somatic hybrid No.12 obtained by protoplast fusion between taro (Colocasia esulenta Schott) cvs. ‘Yatsugahira’and ‘Malaysisa No.4’were investigated. The number of shoot and leaf was smaller than those of ‘Yatsugashira’and was larger than ‘Malaysia No.4’. The length of leaf blade and petiole were shoeter than the two parents. The number of corm was smaller than the two parents. Generally, the shape of top was comoact as compared the two parents. The total weight of corms was about a half of that of ‘Yatsugashira’, and a thirs of that of ‘Malaysia No.4’. The weight of mother corm of somatic hybrid No.12 was 400-500g. The corm morphology of somatic hybrid No.12 was almost intermediate between the two parents. The upper surface of mother corm of somatic hybrid No.12 was smooth; it was much different from that of mother corm of ‘Yatsugashira’. Starch content of borm was similae to ‘Yatsugashira’and smaller than ‘Malaysia No.4’. Sugar and amino acid contents of somatic hybrid No.12 were higher than those of the two parents. Calcium oxalate content was to the parents

Caffeine-Stimulated Intestinal Epithelial Cells Suppress Lipid Accumulation in Adipocytes

Caffeine is a methylxanthine derived from plant foods such as coffee beans and tea leaves, and has multiple biological activities against physiological response and several diseases. Although there are some reports about the direct effect of caffeine against anti-lipid accumulation in vitro, the effect of caffeine on lipid accumulation in adipocytes through stimulating intestinal epithelial cells is unknown. Since direct treatment with caffeine to 3T3-L1 cells did not affect lipid accumulation, we determined whether caffeine-stimulated intestinal epithelial Caco-2 cells influence the lipid accumulation in 3T3-L1 adipocytes. Caco-2 cells were cultured on a transwell insert with or without caffeine for 24 h. Subsequently, the basolateral component of the Caco-2 cell culture on the transwell was collected and termed caffeine-conditioning medium (CCM). When 3T3-L1 adipocytes were incubated with CCM, CCM decreased lipid accumulation and suppressed gene expression of proliferator activated receptor (PPAR) γ and CCAAT/enhancer binding protein (C/EBP) α in 3T3-L1 adipocytes. Furthermore, CCM decreased the expression of C/EBPβ and C/EBPδ at the protein level, but not at the mRNA level. We observed that a proteasome inhibitor, MG132, inhibited CCM-caused down-expression of C/EBPβ and C/EBPδ proteins, and that CCM promoted the ubiquitination level of C/EBPβ and C/EBPδ proteins. Protein microarray analysis showed caffeine suppresses the secretion of inflammatory cytokines, interleukin-8 and plasminogen activator inhibitor-1 from Caco-2 cells. These results suggest that caffeine indirectly suppresses lipid accumulation in 3T3-L1 adipocytes through decreasing secretion of inflammatory cytokines from Caco-2 cells.ArticleJournal of Nutritional Science and Vitaminology. 63(5): 331-338. (2017)journal articl

Theobromine suppresses adipogenesis through enhancement of CCAAT-enhancer-binding protein beta degradation by adenosine receptor A1

Theobromine, a methylxanthine derived from cacao beans, reportedly has various health-promoting properties but molecular mechanism by which effects of theobromine on adipocyte differentiation and adipogenesis remains unclear. In this study, we aimed to clarify the molecular mechanisms of the anti-adipogenic effect of theobromine in vitro and in vivo. ICR mice (4 week-old) were administered with theobromine (0.1 g/kg) for 7 days. Theobromine administration attenuated gains in body and epididymal adipose tissue weights in mice and suppressed expression of adipogenic-associated genes in mouse adipose tissue. In 3T3-L1 preadipocytes, theobromine caused degradation of C/EBP beta protein by the ubiquitin-proteasome pathway. Pull down assay showed that theobromine selectively interacts with adenosine receptor A1(AR1), and AR1 knockdown inhibited theobromine-induced C/ESPfi degradation. Theobromine increased sumoylation of C/EBP beta' at Lys133. Expression of the small ubiquitin-like modifier (SUMO)-specific protease 2 (SENP2) gene, coding for a desumoylation enzyme, was suppressed by theobromine. In vivo knockdown studies showed that AR1 knockdown in mice attenuated the anti-adipogenic effects of theobromine in younger mice. Theobromine suppresses adipocyte differentiation and induced C/EBPP degradation by increasing its sumoylation. Furthermore, the inhibition of AR1 signaling is important for theobromine-induced C/EBP beta degradation.ArticleBIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH.1864(12):2438-2448(2017)journal articl

Theobromine enhances the conversion of white adipocytes into beige adipocytes in a PPARγ activation-dependent manner

The adipocytes play an important role in driving the obese-state—white adipose tissue (WAT) stores the excess energy as fat, wherein brown adipose tissue (BAT) is responsible for energy expenditure via the thermoregulatory function of uncoupling protein 1 (UCP1)—the imbalance between these two onsets obesity. Moreover, the anti-obesity effects of brown-like-adipocytes (beige) in WAT are well documented. Browning, the process of transformation of energy-storing into energy-dissipating adipocytes, is a potential preventive strategy against obesity and its related diseases. In the present study, to explore an alternative source of natural products in the regulation of adipocyte transformation, we assessed the potential of theobromine (TB), a bitter alkaloid of the cacao plant, inducing browning in mice (in vivo) and primary adipocytes (in vitro). Dietary supplementation of TB significantly increased skin temperature of the inguinal region in mice and induced the expression of UCP1 protein. It also increased the expression levels of mitochondrial marker proteins in subcutaneous adipose tissues but not in visceral adipose tissues. The microarray analysis showed that TB supplementation upregulated multiple thermogenic and beige adipocyte marker genes in subcutaneous adipose tissue. Furthermore, in mouse-derived primary adipocytes, TB upregulated the expression of the UCP1 protein and mitochondrial mass in a PPARγ ligand-dependent manner. It also increased the phosphorylation levels of PPARγ coactivator 1α without affecting its protein expression. These results indicate that dietary supplementation of TB induces browning in subcutaneous WAT and enhances PPARγ-induced UCP1 expression in vitro, suggesting its potential to treat obesity.ArticleThe Journal of Nutritional Biochemistry. 100: 108898 (2021)journal articl

Theophylline suppresses interleukin-6 expression by inhibiting glucocorticoid receptor signaling in pre-adipocytes

Adipose tissues in obese individuals are characterized by a state of chronic low-grade inflammation. Pre-adipocytes and adipocytes in this state secrete pro-inflammatory adipokines, such as interleukin 6 (IL-6), which induce insulin resistance and hyperglycemia. Theophylline (1,3-dimethylxanthine) exerts anti-inflammatory effects, but its effects on pro-inflammatory adipokine secretion by pre-adipocytes and adipocytes have not been examined. In this study, we found that theophylline decreased IL-6 secretion by 3T3-L1 pre-adipocytes and mouse-derived primary pre-adipocytes. The synthetic glucocorticoid dexamethasone (DEX) induced IL-6 expression in 3T3-L1 pre-adipocytes, and this effect was suppressed by theophylline at the mRNA level. Knockdown of CCAAT/enhancer binding protein (C/EBP) δ inhibited DEX-induced IL-6 expression, and theophylline suppressed C/EBPδ expression. Furthermore, theophylline suppressed transcriptional activity of the glucocorticoid receptor (GR) through suppression of nuclear localization of GR. In vivo, glucocorticoid corticosterone treatment (100 μg/mL) increased fasting blood glucose and plasma IL-6 levels in C57BL/6 N mice. Theophylline administration (0.1% diet) reduced corticosterone-increased fasting blood glucose, plasma IL-6 levels, and Il6 gene expression in adipose tissues. These results show that theophylline administration attenuated glucocorticoid-induced hyperglycemia and IL-6 production by inhibiting GR activity. The present findings indicate the potential of theophylline as a candidate therapeutic agent to treat insulin resistance and hyperglycemia.ArticleARCHIVES OF BIOCHEMISTRY AND BIOPHYSICS.646:98-106(2018)journal articl

Utilization of Ammoniated Rice Hulls as a Roughage in Barley-Beef Production

アンモニア処理もみ殻(ARH)の飼料価値について検討し,あわせてARHを唯一の粗飼料源としたオールインワン飼料の開発が可能か否かを検討するため,乳用雄子牛6頭を使用し,肥育試験と消化試験を行なった。試験は肥育期(238日)と仕上期(84日)に分け,それぞれTrial 1および2とした。 Trial 1は,開放追込式牛舎で群飼とし,粉砕大麦,ARHおよび添加剤をそれぞれ,80%,14.4%,56%配合したオールインワン飼料(Ration I)を自由採食させた。 Trial 1の終了後,ただちに全頭をスタンチョンに繋留し,Ration Iを引き続き給与した群(大麦区)と大麦をトウモロコシに切替えた群(トウモロコシ区)の2群に,平均体重が等しくなるよう3頭ずつ区分けし,Trial 2を実施した。14日間の飼料切替の後14日間の予備飼育をし,56日間の肥育試験を行なった。 Trial 2の試験終了前に4日間採糞し,消化試験を行なった。それらの結果は次の通りである。 (1) Trial 1の238日間の6頭の平均増体量は241㎏,1日当り増体量は1.01㎏であった。 (2) Tria1 2では,トウモロコシ区の3頭に下痢が発生したため,増体成績は明らかに大麦区より劣った。しかし,枝肉量では両区に差はなかった。 (3) 大麦区およびトウモロコシ区の摂食飼料の消化率(%)は,それぞれ,乾物;71.3, 56.2,粗蛋白質;77.4, 50.6,粗脂肪;75.8, 71.7,粗繊維;17.3, 0, NFE;83.5, 68.6であった。 (4) Trial 1および2においてRation 1を給与した3頭の322日間の増体量は324kgであり,1日当り増体量は1.00kg,肥育終了時体重は584㎏であった。また,肥育期間中の飼料摂取量は1日1頭当り9.45㎏となり,1㎏増体に要したDCP量,TDN量はそれぞれ,0.86㎏, 5.69㎏であった。 (5) 試験開始後22週頃より,各牛とも1～2回の鼓脹症の発生とそれにともなう発育の停滞が見られたが,その治癒とともに,増体も代償的に回復した。各牛にルーメンパラケラトーシスが認められたが,肝のう瘍は認められなかった。 以上の結果から,粉砕大麦,ARHおよび添加剤の単純な配合でも,体重584kg,1日当り増体量1.0㎏の成績は可能であるが,鼓脹症およびルーメンパラケラトーシスの予防についてさらに研究が必要と思われる。Two feeding trials were conducted to estimate the value of ammoniated rice hulls (ARH) as a roughage in barley-beef production. In trial 1, six Holstein steers averaging 265 kg. were fed 80% barley ration for 238 days. This ration (Ration I) contained ground barley, ARH and premix; 80.0%, 14.4% and 5.6%, respectively. The steers were group-fed, twice daily, on an ad libitum basis. In trial 2, the steers were raised in stanchion stalls, immediately after trial 1, and were divided into two groups of three each on a basis of weight. The steers of one group were fed Ration I, and the other ones Ration II containing 80% ground corn, which was substituted for barley in Ration I. This trial was conducted to determine the feeding value and digestion coefficients of both rations. A 28-day preliminary period to allow the steers to adjust to ground corn was followed by a 56-day experimental period. The rations were fed ad libitum with water available at all times by a water-cup. The results collected were as follows: 1) Average weight gain and daily gain for 238 days were respectively 241 kg. and 1.01 kg. in trial 1. 2) Steers fed Ration I gained more than those fed Ration II, which elicited diarrhea. In spite of this, carcass weights were remarkedly similar in both steers fed Ration I and Ration II. 3) Digestion coefficients of Ration I and Ration II were respectively as follows: dry matter; 71.3%, 56.2%, crude protein; 77.4%, 50.6%, crude fat; 75.8%, 71.7%, crude fiber; 17.3%, 0%, NFE; 83.5%, 68.6%. 4) Fattening performance data of steers fed Ration I for 322 days through two trials were as follows: average final weight, daily gain and daily feed intake were respectively 584 kg., 1.00 kg. and 9.45 kg., and the amount of DCP and TDN per kg. of gain were respectively 0.86 kg. and 5.69 kg.. 5) After fattening for a 22-week period, steers sometimes suffered from bloat, so that body weight gain and feed intake decreased. However, the tendency of compensatry growth was observed in all steers, after recovery from this digestive disturbance. Rumens of all steers were generally parakeratotic, however, no incidence of livers abscessation were found. From the above results, it was found that dairy beef steers fed diet containing ground barley, ARH and premix reached successfully a final 584 kg. wt. with 1.00 kg. daily gain except for cases of bloat and rumenparakeratosis. It is necessary to carry out still further experiments so as to find the means to prevent these digestive disturvances

Spin-transfer switching and thermal stability in an FePt/Au/FePt nanopillar prepared by alternate monatomic layer deposition

We fabricated a current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) nanopillar with a 1-nm-thick FePt free layer having perpendicular anisotropy using the alternate monatomic layer deposition method. Nanopillars consisting of [Fe (1 monolayer (ML))/Pt (1 ML)]n (n: the number of the alternation period) ferromagnetic layers and an Au spacer layer showed spin-transfer induced switching at room temperature.Comment: 11 page

NBRP databases: databases of biological resources in Japan

The National BioResource Project (NBRP) is a Japanese project that aims to establish a system for collecting, preserving and providing bioresources for use as experimental materials for life science research. It is promoted by 27 core resource facilities, each concerned with a particular group of organisms, and by one information center. The NBRP database is a product of this project. Thirty databases and an integrated database-retrieval system (BioResource World: BRW) have been created and made available through the NBRP home page (http://www.nbrp.jp). The 30 independent databases have individual features which directly reflect the data maintained by each resource facility. The BRW is designed for users who need to search across several resources without moving from one database to another. BRW provides access to a collection of 4.5-million records on bioresources including wild species, inbred lines, mutants, genetically engineered lines, DNA clones and so on. BRW supports summary browsing, keyword searching, and searching by DNA sequences or gene ontology. The results of searches provide links to online requests for distribution of research materials. A circulation system allows users to submit details of papers published on research conducted using NBRP resources