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Hair follicle stem cells (HFSC) are localized in the bulge region of the hair follicle and play a role in producing hair. Recently, it has been shown that the number of HFSC decreases with age, which is thought to be a cause of senile alopecia. Therefore, maintaining HFSC may be key for the prevention of age-related hair loss, but the regulatory mechanisms of HFSC and the effects of aging on them are largely unknown. In general, stem cells are known to require regulatory factors in the pericellular microenvironment, termed the stem cell niche, to maintain their cell function. In this study, we focused on the extracellular matrix proteoglycan decorin (DCN) as a candidate factor for maintaining the human HFSC niche. Gene expression analysis showed that DCN was highly expressed in the bulge region. We observed decreases in DCN expression as well as the number of KRT15-positive HFSC with age. In vitro experiments with human plucked hair-derived HFSC revealed that HFSC lost their undifferentiated state with increasing passages, and prior to this change a decrease in DCN expression was observed. Furthermore, knockdown of DCN promoted HFSC differentiation. In contrast, when HFSC were cultured on DCN-coated plates, they showed an even more undifferentiated state. From these results, as a novel mechanism for maintaining HFSC, it was suggested that DCN functions as a stem cell niche component, and that the deficit of HFSC maintenance caused by a reduction in DCN expression could be a cause of age-related hair loss., (© 2018 Japanese Dermatological Association.)

New Findings: What is the central question of this manuscript? What is the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the adipose tissue and on energy balance in male rats? What is the main finding and its importance? Calorie intake and fat accumulation in rats fed soft pellets ad libitum increased, but their body weight did not. The data suggest that, even when BMI is normal, frequent consumption of soft food may contribute to the development of lifestyle-related diseases., Abstract: Dietary factors such as food texture are known to affect feeding behaviour and energy metabolism. We recently found that rats fed soft pellets (SPs) on a 3 h restricted feeding schedule showed glucose intolerance, insulin resistance with disruption of insulin signalling, and hyperplasia of pancreatic β-cells, even though there were no differences in energy intake and body weight between rats fed control pellets (CPs) and rats fed SPs. We investigated the effect of food texture on fat accumulation, lipogenesis and proinflammatory factors in the mesenteric fat, as well as on energy balance in male rats fed CPs or SPs. We used 7-week-old Wistar rats that were randomly divided into two groups, ad libitum fed either CPs or SPs for 27 weeks. Body weight and calorie intake were monitored once a week throughout the experiment. The calorie intake, lipogenesis and fat accumulation of the rats fed SPs increased, whereas their body weight did not. Additionally, SP rats used their fat mainly as a source of energy and increased their energy expenditure. Our data suggest that the habit of frequently eating soft food causes visceral fat accumulation without an increase in body weight. Further investigations using soft-textured foods could lead to the development of appropriate interventions for non-overweight patients with lifestyle-related diseases., (© 2018 The Authors. Experimental Physiology © 2018 The Physiological Society.)

Background and Objective: The tooth root is one of the critical parts to maintain tooth function; however, the molecular mechanisms of root development remain unknown. We aimed to identify specific factors for root morphogenesis using a newly developed experimental system., Material and Methods: Tentative cementoblasts and periodontal ligament cells from mouse mandibular molars were isolated using laser capture microdissection. More than 500 cementoblasts and periodontal ligament cells were separately captured. After RNA extraction and amplification, mRNA expression in isolated cementoblasts was compared with that of periodontal ligament cells by cDNA microarray analysis. Then, putative cementoblast-specific genes were subjected to in situ hybridization analysis to confirm the results in mouse mandible., Results: Approximately 2000 genes were differentially expressed between these tissues. Among those genes, zinc finger helicase (ZFH), also termed chromodomain-helicase-DNA-binding protein 3 (Chd3), was one of the highly expressed transcripts in tentative cementoblasts. In situ hybridization revealed that ZFH/Chd3 was strongly expressed in Hertwig's epithelial root sheath rather than in cementum. Moreover, its expression disappeared when root formation was advanced in the first molar. In contrast, Chd3 was continuously expressed in dental epithelial cells of the cervical loop, in which root extension is never terminated., Conclusion: These results suggest that ZFH/Chd3 might play an important role in tooth root development and subsequent cementogenesis., (© 2011 John Wiley & Sons A/S.)

Although orexin-A peptide was recently found to inhibit the brain reward system, the exact neural substrates for this phenomenon remain unclear. The aim of the present study was to investigate the role of orexin neurons in intra-cranial self-stimulation behavior and to clarify the pathways through which orexin-A inhibits the brain reward system. Immunohistochemical examination using Fos, a neuronal activation marker, revealed that the percentage of activated orexin cells was very low in the lateral hypothalamus even in the hemisphere ipsilateral to self-stimulation, suggesting that orexin neurons play only a small part, if any, in performing intra-cranial self-stimulation behavior. Intra-ventral tegmental area administration of orexin-A (1.0 nmol) significantly increased the intra-cranial self-stimulation threshold. Furthermore, the threshold-increasing effects of intra-ventral tegmental area or intracerebroventricular orexin-A were inhibited by administration of the nonspecific corticotropin-releasing factor receptor antagonist, d-Phe-CRF(12-41) (20 μg). Following intra-ventral tegmental area infusion of orexin-A, the percentage of cells double-labeled with corticotropin-releasing factor and Fos antibodies increased in the central nucleus of the amygdala but not in the bed nucleus of the stria terminalis, and brain microdialysis analyses indicated that dopamine efflux in both the central nucleus of the amygdala and bed nucleus of the stria terminalis were enhanced. Taken together, the present findings suggest that intra-ventral tegmental area or intracerebroventricular administration of orexin-A exerts its threshold-increasing effect via subsequent activation of the corticotropin-releasing factor system., (© 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.)

Objective: To study polymorphisms in the 5'-flanking promoter/enhancer region of the tumor necrosis factor alpha (TNFalpha) gene and in the coding regions of HLA class I and class II genes, in order to better understand the genetic background of juvenile rheumatoid arthritis (JRA)., Methods: One hundred eleven Japanese JRA patients (50 with systemic disease, 29 with pauciarticular disease, and 32 with polyarticular disease) and 575 healthy Japanese subjects were examined for the allele frequencies of the TNFalpha, HLA-A, and HLA class II (DRB1, DRB3, DRB4, DRB5, DQA1, DQB1, DPA1, and DPB1) genes, by DNA typing using the polymerase chain reaction-sequence-specific oligonucleotide probe method., Results: The frequencies of the polymorphic allele at positions -1,031 (T to C substitution, termed -1,031C), -863 (C to A, termed -863A), and -857 (C to T, termed -857T) of the TNFalpha gene in patients with systemic JRA, but not in those with polyarticular or pauciarticular JRA, were significantly higher than in the healthy controls. The allele frequencies of DRB1*0405 and DQB1*0401 in systemic JRA, but not in the other JRA types, were significantly higher than in controls. Linkage analysis showed that the presence of both the TNFalpha -857T allele and DRB1*0405 yielded a significantly increased odds ratio (3.84), while the presence of only 1 of them did not yield a high odds ratio (0.87 and 1.58)., Conclusion: The -1,031C/-863A allele and the -857T allele of the TNFalpha gene, both of which are related to high production of tumor necrosis factor alpha, are associated with systemic JRA. The -857T allele may enhance the effect of the DRB1*0405/DQB1*0401 haplotype in predisposing to development of systemic JRA.