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Mesenchymal stem cells (MSCs) are pluripotent stem cells present in various tissues. Previous studies have shown that maxillary/mandibular bone marrow-derived MSCs (MBMSCs) scarcely differentiate into adipocytes. However, the regulatory molecular mechanisms underlying adipogenic differentiation of MBMSCs remain unknown. We investigated the underlying molecular mechanisms that regulate adipogenic differentiation of MBMSCs. We observed no significant differences in cell surface antigen profiles and stem cell marker gene expression in MBMSCs and iliac bone marrow-derived MSCs (IBMSCs). MBMSCs and IBMSCs displayed similar osteogenic and chondrogenic differentiation potentials, whereas MBMSCs showed significantly lower lipid accumulation, adipocyte marker gene expression, and intracellular glucose uptake than that showed by IBMSCs. Expression of CCAAT/enhancer binding protein β (C/EBPβ), C/EBPδ, early B-cell factor 1 (Ebf-1), and Krüppel-like factor 5 (KLF5), which are transcription factors expressed early in adipogenic differentiation, was suppressed in MBMSCs compared to that in IBMSCs. Peroxisome proliferator-activated receptor-γ (PPARγ) and C/EBPα, which play important roles in the terminal differentiation of preadipocytes into mature adipocytes, were increased during adipogenic differentiation in MBMSCs and IBMSCs; however, the expression level of these genes in MBMSCs was lower than that in IBMSCs. Furthermore, the level of zinc finger protein 423 (Zfp423), which is involved in the commitment of undifferentiated MSCs to the adipocyte lineage, was significantly lower in undifferentiated MBMSCs than that in IBMSCs. These data indicate that MBMSCs are negatively regulated in the commitment of undifferentiated MSCs to the adipocyte lineage (preadipocytes) and in terminal differentiation into mature adipocytes. These results may elucidate the site-specific characteristics of MBMSCs.

Purple sweet potato (Ipomoea batatas L.) leaf extract (PSPLE) is known to exhibit various biological effects. However, the anti-adipogenic effects of PSPLE on mesenchymal stem cells (MSCs) remain unknown. In the present study, we investigated the effect of PSPLE on the adipogenic differentiation of human bone marrow MSCs. PSPLE treatment significantly reduced lipid accumulation and triglyceride levels during adipogenic differentiation. PSPLE suppressed the expression of PPARγ and C/EBPα, which are the master transcription factors orchestrating adipogenesis; moreover, it inhibited the expression of adiponectin, adipocyte protein 2 (aP2), and lipoprotein lipase (LPL), which are downstream target genes involved in adipogenic differentiation. Furthermore, PSPLE treatment suppressed glucose transporter 4 expression and intracellular glucose uptake and significantly inhibited the adipogenic differentiation induced factor-stimulated Akt signaling activation. These results indicate that PSPLE suppresses the differentiation of undifferentiated MSCs into adipocyte lineages and inhibits the terminal differentiation from preadipocytes into mature adipocytes. PRACTICAL APPLICATION: The increase in the prevalence of obesity worldwide is a problem today. Obesity is induced by an excessive accumulation of adipocytes and causes obesity-related diseases, such as diabetes, hypertension, and hyperlipidemia. Natural compounds derived from plants and fruits have a variety of biological activities and are expected to exert therapeutic effects against various diseases. This study shows that purple sweet potato (Ipomoea batatas L.) leaf extract (PSPLE) suppresses adipogenesis of bone marrow-derived mesenchymal stem cells. Thus, PSPLE may be a novel functional food for controlling obesity.

Mechanistic target of rapamycin complex 1 (mTORC1) is a master growth regulator by controlling protein synthesis and autophagy in response to environmental cues. Amino acids, especially leucine and arginine, are known to be important activators of mTORC1 and to promote lysosomal translocation of mTORC1, where mTORC1 is thought to make contact with its activator Rheb GTPase. Although amino acids are believed to exclusively regulate lysosomal translocation of mTORC1 by Rag GTPases, how amino acids increase mTORC1 activity besides regulation of mTORC1 subcellular localization remains largely unclear. Here we report that amino acids also converge on regulation of the TSC2-Rheb GTPase axis via Ca2+/calmodulin (CaM). We showed that the amino acid-mediated increase of intracellular Ca2+ is important for mTORC1 activation and thereby contributes to the promotion of nascent protein synthesis. We found that Ca2+/CaM interacted with TSC2 at its GTPase activating protein (GAP) domain and that a CaM inhibitor reduced binding of CaM with TSC2. The inhibitory effect of a CaM inhibitor on mTORC1 activity was prevented by loss of TSC2 or by an active mutant of Rheb GTPase, suggesting that a CaM inhibitor acts through the TSC2-Rheb axis to inhibit mTORC1 activity. Taken together, in response to amino acids, Ca2+/CaM-mediated regulation of the TSC2-Rheb axis contributes to proper mTORC1 activation, in addition to the well-known lysosomal translocation of mTORC1 by Rag GTPases.

We propose and demonstrate a compact snapshot-type multispectral image sensor. The sensor consists of a CCD area sensor and a photonic crystal (PhC) type patterned spectral filter array. The perpendicular refractive index profile of the PhC roughly determines the spectral response, while the in-plane periodic structure slightly modifies it. As a result, a multi-patterned filter array with each spatial region exhibiting different transmission characteristic. The filter was directly mounted onto a CCD to construct an imaging spectrometer. Application to near infrared inspection of agricultural products (fruits) was investigated. Spectral reflectivity images at wavelengths between 610nm to 810nm were predicted with the aid of Wiener estimation algorithm.

Cyclamen aldehyde (Cya) is an essential oil component with an aldehyde group. The current study examined an inclusion complex of Cya and β-cyclodextrin (βCD) and assessed its physicochemical properties, volatility, and stability. Phase solubility diagrams and 1H NMR spectroscopy indicated that Cya and βCD in a co-precipitate (CP) form a complex at a molar ratio of 1/1. Powder X-ray diffraction (PXRD) patterns revealed crystal diffraction peaks due to βCD (2θ = 8.8°, 12.5°, and 20.8°) for the PM and new diffraction peaks (2θ = 11.7° and 17.5°) for the CP. Thermogravimetry (TG) measurements indicated that Cya decreased about 18.2% in a physical mixture (PM) and about 4.4% in the CP. FT-IR and NIR spectroscopies indicated that the spectra produced by the methyl groups and isopropyl group (5908 cm−1) of Cya and by the hydroxyl groups (4756 cm−1) in the cavity of βCD shifted. {1H–1H} NOESY NMR spectra revealed couplings for the protons of the isopropyl group (1.05 ppm) and the protons of the βCD cavity (H-3: 3.66 ppm). These findings indicated that the isopropyl group of Cya is included in the wider opening of the βCD torus. Diffusion-ordered two-dimensional NMR spectroscopy (DOSY) indicated that the CP (Cya/βCD) had a diffusion coefficient of 3.21 × 10−5 cm2/s and that βCD had a diffusion coefficient of 3.25 × 10−5 cm2/s, so the CP (Cya/βCD) had colligate properties like those of βCD. A stability test at a temperature of 40 °C and RH of 82% revealed that Cya decreased about 7.4% in 7 d, but at least 29% of the CP (Cya/βCD) was retained. At a temperature of 25 °C and RH of 84%, Cya decreased about 9.7% in 7 d, but at least 76.5% of the CP (Cya/βCD) was retained. These findings indicated that formation of a complex by the CP (Cya/βCD) should reduce the volatility of Cya and improve its stability.

We fabricated 16-, 25-, 36-, and 64-channel distributed passband-type multi-spectral filter arrays by utilizing a multilayer-type photonic crystal and integrated them onto a CCD to form a snapshot-type spectroscopic sensor. Reflection spectra from target objects (fruits) under broadband light illumination were estimated directly using the Wiener estimation method. A root mean square error of the reflectivity on the order of 2 ∼ 5 % was obtained under optical shot noise with 6 × 6 pixel binning. A number of constituent filters of 36 was sufficient for this type of fruit spectral measurement. We also visualized reflection images at specified wavelengths by applying the estimation method to a multiple filter region on the sensor.

L-Ascorbic acid (AA), known as vitamin C, can form browning products by a non-enzymatic process during storage and the browning products cause deterioration of agricultural products. In the browning reaction, a red pigment, 2,2´-nitrilodi-2(2´)-deoxy-L-ascorbic acid ammonium salt (NDA), is generated from AA via L-scorbamic acid (SCA) as an intermediate. However, the biological activities of SCA and NDA have not yet been clarified. In this study, we assayed the antioxidant activities of SCA and NDA using ABTS radical cation and their neurite outgrowth-enhancing activities in PC12 cells. SCA showed stronger radical-scavenging activity than that of AA, while NDA hardly showed any activity. SCA and NDA enhanced the neurite outgrowth induced by dibutyryl cyclic AMP after their incorporation into cells in the same manner as that of AA. The results indicated that SCA has antioxidant activity and that SCA and NDA have neurite outgrowth-enhancing activity.

Micro RNA (miRNA) is a small non-coding post-transcriptional RNA regulator that is involved in a variety of biological events. In order to specify the role of miRNAs in cartilage metabolism, we comparatively analyzed the expression profile of known miRNAs in chicken sternum chondrocytes representing early and late differentiation stages. Interestingly, none of the miRNAs displaying strong expression levels showed remarkable changes along with differentiation, suggesting their roles in maintaining the homeostasis rather than cytodifferentiation of chondrocytes. Among these miRNAs, miR-181a, which is known to play critical roles in a number of tissues, was selected and was further characterized. Human microarray analysis revealed remarkably stronger expression of miR-181a in human HCS-2/8 cells, which strongly maintained a chondrocytic phenotype, than in HeLa cells, indicating its significant role in chondrocytes. Indeed, subsequent investigation indicated that miR-181a repressed the expression of two genes involved in cartilage development. One was CCN family member 1 (CCN1), which promotes chondrogenesis; and the other, the gene encoding the core protein of aggrecan, a major cartilaginous proteoglycan, aggrecan. Based on these findings, negative feedback system via miR-181a to conserve the integrity of the cartilaginous phenotype may be proposed.

Release rates of particulate organic carbon and nitrogen (POC and PON) and dissolved organic carbon (DOC) from the scleractinian coral Acropora tenuis were measured during the day and night in summer and winter seasons. Physiological parameters including calcification, photosynthesis and respiration rates were also measured simultaneously. The release rate of both POC and DOC was significantly higher in summer compared to winter and higher during the day compared to the night. The daily release rate of total organic carbon (POC + DOC) was 1,094 and 219 μmol C cm−2 d−1 for summer and winter, respectively, being 4.9 times higher in summer. The POC:PON ratios of the particulate organic matter released during daytime in both seasons (summer: 12.8 ± 5.7, winter: 12.0 ± 4.1) were significantly higher than those during nighttime (summer: 6.1 ± 2.5, winter: 2.2 ± 1.8). The DOC:POC ratio was 0.5 ± 0.03 during summer and 0.32 ± 0.98 during winter, suggesting higher mucus release in particulate form. Daily net production was estimated to be 199 and 158 μg C cm−2d−1 for summer and winter, respectively, with the amount of carbon released as mucus accounting for 6.5% and 1.6% of the net carbon fixation, respectively. The study reveals diurnal and seasonal changes in the quantity and quality of mucus released from this coral species. Since coral mucus is used as a food source by reef macro-organisms, and can also serve as an energy source for micro-organisms, the observed changes in mucus release rates are expected to influence the seasonal dynamics of organic carbon and nitrogen cycling over coral reefs.

Micro RNA (miRNA) is a small non-coding post-transcriptional RNA regulator that is involved in a variety of biological events. In order to specify the role of miRNAs in cartilage metabolism, we comparatively analyzed the expression profile of known miRNAs in chicken sternum chondrocytes representing early and late differentiation stages. Interestingly, none of the miRNAs displaying strong expression levels showed remarkable changes along with differentiation, suggesting their roles in maintaining the homeostasis rather than cytodifferentiation of chondrocytes. Among these miRNAs, miR-181a, which is known to play critical roles in a number of tissues, was selected and was further characterized. Human microarray analysis revealed remarkably stronger expression of miR-181a in human HCS-2/8 cells, which strongly maintained a chondrocytic phenotype, than in HeLa cells, indicating its significant role in chondrocytes. Indeed, subsequent investigation indicated that miR-181a repressed the expression of two genes involved in cartilage development. One was CCN family member 1 (CCN1), which promotes chondrogenesis; and the other, the gene encoding the core protein of aggrecan, a major cartilaginous proteoglycan, aggrecan. Based on these findings, negative feedback system via miR-181a to conserve the integrity of the cartilaginous phenotype may be proposed.