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Abstract: MicroRNAs (miRs) regulate several biological functions such as cell growth, cell differentiation, and carcinogenesis, by binding to the 3′-untranslated regions (3′-UTR) of specific target genes, in order to repress translation or promote degradation of the transcribed mRNAs. In the present study, using microRNA array and in silico analyses, we found that miR-370 regulates the expression of bone morphogenetic protein-2 (BMP-2) and V-ets Erythroblastosis Virus E26 Oncogene Homolog 1 (Ets1) in BMP-2-stimulated murine pre-osteoblast MC3T3-E1 cell differentiation. The enforced expression of mature miR-370 in MC3T3-E1 cells or primary osteoblast cells remarkably attenuated BMP-2-induced pre-osteoblast differentiation. To ascertain the mechanisms underlying the regulation of osteoblast differentiation by miR-370, we hypothesized a BMP-2-Ets1-PTHrP feed-forward loop regulatory mechanism. [Copyright &y& Elsevier]

Aquaporin 12 (AQP12) is the most recently identified member of the mammalian AQP family and is specifically expressed in pancreatic acinar cells. In vitro expression studies have revealed that AQP12 is localized at intracel- lular sites. To determine the physiological roles of AQP12 in the pancreas, we generated knockout mice for this gene (AQP12-KO). No obvious differences were observed under normal conditions between wild-type (WT) and AQP12-KO mice in terms of growth, blood chemistry, pancreatic fluid content, or histology. However, when we induced pancreatitis through the administration of a cholecystokinin-8 (CCK-8) analog, the AQP12-KO mice showed more severe patholog- ical damage to this organ than WT mice. Furthermore, when we analyzed exocytosis in the pancreatic acini using a two-photon excitation imaging method, the results revealed larger exocytotic vesicles (vacuoles) in the acini of AQP12-KO mice at a high CCK-8 dose (100 nM). From these results, we conclude that AQP12 may function in the mechanisms that control the proper secretion of pancreatic fluid following rapid and intense stimulation. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) are endogenously expressed 18-25-nucleotide RNAs that regulate gene expression through translational repression by binding to a target mRNA. Recently, it was indicated that miRs act as key regulators in cell differentiation cell growth, and cell death. In osteogenesis, several miRs (for example miR-26a, -125b, -133, and -135) regulate osteoblast cell growth or differentiation in human adipose tissue-derived steni cells, mouse mesenchymal ST2 stem cells, and mouse premyogenic C2C12 cells. Additionally, Smad proteins control Droshamediated miR maturation. Therefore, miRs are closely related to osteogenesis. Here we investigated miR expression profile by an miR array and identified the candidate miRs, miR-141 and -200a, as pre-osteoblast differentiation-related miRs. The effects of miR-141 and -200a on pre-osteoblast differentiation were examined by using transfection of murine pre-osteoblastic MC3T3-E1 cells with mature miR-141 or -200a and antisense inhibitor for miR-141 or -200a. It was shown that miR-141 and -200a remarkably modulated the BMP-2-induced pre-osteoblast differentiation through the translational repression of D1x5, which is a bone-generating transcription factor expressed in pre-osteoblast differentiation. Furthermore, it was indicated that DlxS is a common target of miR-141 and -200a by using a luciferase reporter assay. Thus, we have observed for the first time that miR-141 and -200a are involved in pre-osteoblast differentiation in part by regulating the expression of D1x5. [ABSTRACT FROM AUTHOR]

Abstract: Sesquiterpene lactones (SQTLs) have been shown to suppress the degranulation as inferred by histamine release in rat basophilic leukemia RBL-2H3 cells. In this study, we isolated the 9 kinds of SQTLs from Eupatorium chinense L. and examined the effects of these SQTLs on the degranulation in RBL-2H3 cells. The chemical structures of two novel compounds (SQTL-3 and 8) were determined. All the SQTLs suppressed the degranulation from Ag-stimulated RBL-2H3 cells. To disclose the inhibitory mechanism of degranulation by SQTLs, we examined the activation of intracellular signaling molecules such as Lyn, Syk, and PLCγs and intracellular free Ca2+ concentration ([Ca2+]i). None of these SQTLs showed the activation of Syk and PLCγs. The intracellular free Ca2+ concentration ([Ca2+]i) was elevated by FcεRI activation, but SQTLs treatment reduced the elevation of [Ca2+]i by suppressing Ca2+ influx. Thus, it was suggested that the suppression of Ag-stimulated degranulation by these SQTLs is mainly due to the decreased Ca2+ influx. Furthermore, in order to clarify the in vivo effect of SQTL-rich extract, we administered SQTL-rich extract to the type I allergic model mice and measured the passive cutaneous anaphylaxis (PCA) reaction induced by IgE-antigen complex. The SQTLs remarkably suppressed PCA reaction in a dose-dependent manner. Thus, it was suggested that SQTLs would be a candidate as an anti-allergic agent. [Copyright &y& Elsevier]

Abstract: Objective: Recently, we reported that 40% ethanol fraction of hot-water extracts of adzuki (Vigna angularis; EtEx.40) suppressed the postprandial blood glucose level and serum insulin level in normal mice and streptozotocin-induced type 1 diabetic rats. The present study examined the hypoglycemic effect of EtEx.40 on blood glucose, insulin concentrations, organ weight, serum composition, and hepatic lipid content in spontaneously diabetic KK-Ay/Ta Jcl mice, a model for type 2 diabetes. Methods: To investigate the prevention of type 2 diabetes by EtEx.40 ingestion, 4-wk-old non-diabetic KK-Ay mice were fed an AIN-76 diet containing 5000 mg of EtEx.40/kg of body weight per day (EtEx.40) or an AIN-76 diet without EtEx.40 for 8 wk. Furthermore, to investigate the improvement of type 2 diabetes, 7-wk-old diabetic KK-Ay mice were fed EtEx.40 for 4 wk. Results: Compared with the control group, EtEx.40 supplementation had a significant effect in lowering blood glucose levels, water intake, serum insulin levels, urinary glucose, urinary microalbumin/creatinine ratio, liver triacylglycerol, and total cholesterol levels. Similar results were observed in 7-wk-old diabetic KK-Ay mice fed EtEx.40 for 4 wk. These effects were also found after short-term administration of EtEx40. Overall, EtEx.40 improved several diabetic symptoms in KK-Ay mice. Conclusion: EtEx.40 obtained from hot-water adzuki extracts showed preventive and ameliorative effects on the progression of diabetes in genetically diabetic KK-Ay mice. In the present study, we conclude that the preventive and ameliorative effects by EtEx.40 were due to the modulation of blood glucose levels and the protective effect against oxidative damage in diabetes mellitus. [Copyright &y& Elsevier]

Investigates the stimulation of melanogenesis by the hot water extract of adzuki beans (Vigna angularis) in cultured murine B16 melanoma cells and C3H mice. Indication that the distilled water fraction (WEx) can stimulate tyrosinase activity in cultured mouse B16 melanoma cells and hair color pigmentation in C3H mice; WEx stimulation of melanogenesis without inhibiting cell growth; Finding that WEx have pigmentation activity on hair color in C3H mice.

Reports that a hot water extract obtained by boiling adzuki beans, Vigna angularis, to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. Preparation of the test materials; Oral glucose tolerance test on normal mice; Oral glucose tolerance test on rats with streptozotocin-induced diabetes.

The article presents a study which investigates the effect of theaflavins found in black tea on melanogenesis. It states that the various theaflavins were investigated by their effects on mouse B16 melanoma cells and assessed by melanin content. Moreover, the study reveals that TF-3, a component of theaflavins, mediated by tyrosine enzyme messenger ribonucleic acid (mRNA).