Naphthalene and phenanthrene are transformed by enzymes encoded by the pah gene cluster ofPseudomonas putida OUS82. The pahA and pahB genes, which encode the first and second enzymes, dioxygenase and cis-dihydrodiol dehydrogenase, respectively, were identified and sequenced. The DNA sequences showed that pahA and pahB were clustered and that pah/A consisted of four cistrons, pah/Aa paMAb, pahAc, and pahAd, which encode ferredoxin reductase, ferredoxin, and two subunits of the iron-sulfur protein, respectively.Pseudomonas putida OUS82 can assimilate naphthalene and phenanthrene as its sole carbon sources. The strain converts naphthalene and phenanthrene to salicylate and 1-hydroxy-2-naphthoate, respectively, by a shared catabolic pathway (the upper pathway; Fig. 1). Salicylate and 1-hydroxy-2-naphthoate are further degraded by other catabolic enzymes. The enzymes in the upper pathway have broad substrate specificities, and various polycyclic aromatic hydrocarbons other than naphthalene and phenanthrene are oxidized by a high-density suspension of OUS82 cells (9).Previously, we cloned the gene cluster encoding the enzymes of the upper pathway and named it pah (polycyclic aromatic hydrocarbon; 9). The pah region strongly hybridized to a corresponding region of plasmid NAH7 of P. putida G7, which degrades naphthalene (4). All recombinant plasmids carrying pahA have 6.5-and 3.0-kb Sall fragments. The two fragments were seen to be necessary for the dioxygenase phenotype (PahA). A restriction endonuclease map of a region in the fragments resembles that of the nahA region of NAH7 and pDTG1 in P. putida G7 and NCIB 9816-4, which degrade naphthalene (2, 4, 23). The pahA gene was expected to be in that region.Here, we describe the identification and characterization of the pahA and pahB genes, which encode dioxygenase PahA, which is the first enzyme of the pathway and converts polycyclic aromatic hydrocarbon (PAH) to the corresponding cis-dihydrodiol, and dehydrogenase PahB, the second enzyme of the pathway, which converts the product of PahA to the corresponding diol. P. putida OUS8211 (trp-82 Apah-821), a derivative of strain OUS82 that is defective in naphthalene and phenanthrene utilization, and plasmid pDIl, which carries the pahAB gene cluster, were described previously (9). Plasmid NAH7 was described elsewhere (4, 5). Escherichia coli JM109 and plasmid pUC119 were described by Yanisch-Perron et al. (21)

BackgroundPerilipin A (PeriA) exclusively locates on adipocyte lipid droplets and is essential for lipid storage and lipolysis. Previously, we reported that adipocyte specific overexpression of PeriA caused resistance to diet-induced obesity and resulted in improved insulin sensitivity. In order to better understand the biological basis for this observed phenotype, we performed additional studies in this transgenic mouse model.Methodology and Principal FindingsWhen compared to control animals, whole body energy expenditure was increased in the transgenic mice. Subsequently, we performed DNA microarray analysis and real-time PCR on white adipose tissue. Consistent with the metabolic chamber data, we observed increased expression of genes associated with fatty acid β-oxidation and heat production, and a decrease in the genes associated with lipid synthesis. Gene expression of Pgc1a, a regulator of fatty acid oxidation and Ucp1, a brown adipocyte specific protein, was increased in the white adipose tissue of the transgenic mice. This observation was subsequently verified by both Western blotting and histological examination. Expression of RIP140, a regulator of white adipocyte differentiation, and the lipid droplet protein FSP27 was decreased in the transgenic mice. Importantly, FSP27 has been shown to control gene expression of these crucial metabolic regulators. Overexpression of PeriA in 3T3-L1 adipocytes also reduced FSP27 expression and diminished lipid droplet size.ConclusionsThese findings demonstrate that overexpression of PeriA in white adipocytes reduces lipid droplet size by decreasing FSP27 expression and thereby inducing a brown adipose tissue-like phenotype. Our data suggest that modulation of lipid droplet proteins in white adipocytes is a potential therapeutic strategy for the treatment of obesity and its related disorders.

Journal of Lipid ResearchObesity is associated with metabolic dysfunction and increased risk for diabetes, cardiovascular disease, cancer, and early mortality ( 1, 2 ). In both lean and obese states, triacylglycerol is predominately stored within lipid droplets of adipocytes. Perilipin A (PeriA) is the most abundant phosphoprotein on adipocyte lipid droplets and is an important regulator of lipid storage and release (lipolysis) ( 3, 4 ). In the absence of hormonal stimulation (basal state), PeriA functions to inhibit the actions of lipases on stored neutral lipids, thereby maintaining a low rate of constitutive lipolysis (promotes lipid storage) ( 5-10 ). Catecholamines enhance adipocyte lipolysis by stimulating adenylate cyclase activity and consequently activating cAMP-dependent protein kinase A (PKA), which simultaneously phosphorylates perilipin and hormone-sensitive lipase (HSL) ( 3,11,12 ). PKA-dependent phosphorylation of multiple serine residues on perilipin releases CGI-58 from the lipid droplet protein, resulting in enhanced activity of adipose triglyceride lipase (ATGL) ( 13, 14 ) and enhanced HSL accessibility to lipid stores ( 4,5,10,(15)(16)(17). As a result of these combined actions, lipolysis is dramatically increased.Abstract Perilipin A is the most abundant phosphoprotein on adipocyte lipid droplets and is essential for lipid storage and lipolysis. Perilipin null mice exhibit diminished adipose tissue, elevated basal lipolysis, reduced catecholamine-stimulated lipolysis, and increased insulin resistance. To understand the physiological consequences of increased perilipin expression in vivo, we generated transgenic mice that overexpressed either human or mouse perilipin using the adipocyte-specifi c aP2 promoter/enhancer. Phenotypes of female transgenic and wild-type mice were characterized on chow and high-fat diets (HFDs). When challenged with an HFD, transgenic mice exhibited lower body weight, fat mass, and adipocyte size than wild-type mice. Expression of oxidative genes was increased and lipogenic genes decreased in brown adipose tissue of transgenic mice. Basal and catecholaminestimulated lipolysis was decreased and glucose tolerance signifi cantly improved in transgenic mice fed a HFD. Perilipin overexpression in adipose tissue protects against HFD-induced adipocyte hypertrophy, obesity, and glucose intolerance. Alterations in brown adipose tissue metabolism may mediate the effects of perilipin overexpression on body fat, although the mechanisms by which perilipin overexpression alters brown adipose tissue metabolism remain to be determined. Our fi ndings demonstrate a novel role for perilipin expression in adipose tissue metabolism and regulation of obesity and its metabolic complications. -Miyoshi,

BackgroundOral functions are known to decline with aging. However, there is limited evidence that supports the relationship between oral health and frailty. This study aimed to clarify the relationship between oral hygiene conditions, measured by remaining teeth and mucosa, and frailty among elderly people dwelling in a Japanese rural community.MethodsWe surveyed self-reliant elderly individuals aged ≥65 years who were dwelling in the Sasayama-Tamba area of Hyogo, Japan. Frailty was evaluated according to the total score of the Kihon Checklist (KCL). Based on the KCL score, elderly participants were divided into three groups: robust, pre-frail, and frail. The items measured to evaluate oral environment included the number of remaining teeth, denture usage condition, oral hygiene status, dry mouth condition, and salivary bacterial count. For statistical analysis, Fisher’s exact test, one-way analysis of variance, and multiple comparison technique were used.ResultsOf 308 elderly participants, 203 (65.9%), 85 (27.6%), and 20 (6.5%) belonged to the robust, pre-frail, and frail groups, respectively. The proportion of participants who were judged to have poor hygiene was significantly higher in the frail group than in the other two groups. The bacterial count was significantly smaller in the frail group than in the robust group, and the frail group had fewer number of remaining teeth than the other two groups, suggesting that the number of remaining teeth may be associated with bacterial count.ConclusionIn elderly adults, physical frailty may affect the oral hygiene status and condition of the remaining teeth.

In this study, we developed a new method to stimulate osteogenic differentiation in tissue-nonspecific alkaline phosphatase (TNAP)-positive cells liberated from human induced pluripotent stem cells (hiPSCs)-derived embryoid bodies (EBs) with 14 days long TGF-β/IGF-1/FGF-2 treatment. TNAP is a marker protein of osteolineage cells. We analyzed and isolated TNAP-positive and E-cadherin-negative nonepithelial cells by fluorescence-activated cell sorting. Treating the cells with a combination of transforming growth factor (TGF)-β, insulin-like growth factor (IGF)-1, and fibroblast growth factor (FGF)-2 for 14 days greatly enhanced TNAP expression and maximized expression frequency up to 77.3%. The isolated cells expressed high levels of osterix, which is an exclusive osteogenic marker. Culturing these TNAP-positive cells in osteoblast differentiation medium (OBM) led to the expression of runt-related transcription factor 2, type I collagen, bone sialoprotein, and osteocalcin (OCN). These cells responded to treatment with activated vitamin D3 by upregulating OCN. Furthermore, in OBM they were capable of generating many mineralized nodules with strong expression of receptor activator of NF-kappaB ligand and sclerostin (SOST). Real-time RT-PCR showed a significant increase in the expression of osteocyte marker genes, including SOST, neuropeptide Y, and reelin. Scanning electron microscopy showed dendritic morphology. Examination of semi-thin toluidine blue-stained sections showed many interconnected dendrites. Thus, TNAP-positive cells cultured in OBM may eventually become terminally differentiated osteocyte-like cells. In conclusion, treating hiPSCs-derived cells with a combination of TGF-β, IGF-1, and FGF-2 generated TNAP-positive cells at high frequency. These TNAP-positive cells had a high osteogenic potential and could terminally differentiate into osteocyte-like cells. The method described here may reveal new pathways of osteogenesis and provide a novel tool for regenerative medicine and drug development.

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S U M M A R Y Among elastic system fibers, oxytalan fibers are known as a ubiquitous component of the periodontal ligament, but the localization and role of elastin-containing fibers, i.e., elastic and elaunin fibers, has yet to be clarified. In this study, we immunohistochemically investigated the localization of elastin and fibrillin, major proteins of elastin-containing fibers in the periodontal ligament of rat lower first molars. At the light microscope level, distribution of elastin-positive fibers was not uniform but often concentrated in the vicinity of blood vessels in the apical region of the ligament. In contrast, fibrillin-positive fibers were more widely distributed throughout the ligament, and the pattern of their distribution was comparable to the reported distribution of oxytalan fibers. At the ultrastructural level, assemblies or bundles of abundant fibrillin-containing microfibrils were intermingled with a small amount of elastin. This observation indicated that elastin-positive fibers observed under the light microscope were elaunin fibers. No mature elastic fibers, however, were found in the ligament. These results show that the major components of elastic system fibers in the periodontal ligament of the rat mandibular first molar were oxytalan and elaunin fibers, suggesting that the elastic system fibers play a role in the mechanical protection of the vascular system.

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