In chronic kidney disease, fibroblast dysfunction causes renal fibrosis and renal anemia. Renal fibrosis is mediated by the accumulation of myofibroblasts, whereas renal anemia is mediated by the ...reduced production of fibroblast-derived erythropoietin, a hormone that stimulates erythropoiesis. Despite their importance in chronic kidney disease, the origin and regulatory mechanism of fibroblasts remain unclear. Here, we have demonstrated that the majority of erythropoietin-producing fibroblasts in the healthy kidney originate from myelin protein zero-Cre (P0-Cre) lineage-labeled extrarenal cells, which enter the embryonic kidney at E13.5. In the diseased kidney, P0-Cre lineage-labeled fibroblasts, but not fibroblasts derived from injured tubular epithelial cells through epithelial-mesenchymal transition, transdifferentiated into myofibroblasts and predominantly contributed to fibrosis, with concomitant loss of erythropoietin production. We further demonstrated that attenuated erythropoietin production in transdifferentiated myofibroblasts was restored by the administration of neuroprotective agents, such as dexamethasone and neurotrophins. Moreover, the in vivo administration of tamoxifen, a selective estrogen receptor modulator, restored attenuated erythropoietin production as well as fibrosis in a mouse model of kidney fibrosis. These findings reveal the pathophysiological roles of P0-Cre lineage-labeled fibroblasts in the kidney and clarify the link between renal fibrosis and renal anemia.
The major lysosomal proteases, Cathepsin B (CTSB), Cathepsin D (CTSD) and Cathepsin L (CTSL), are implicated in autophagic activity. To investigate the role of each cathepsin in the exocrine ...pancreas, we generated mice in which the pancreas was specifically deficient in Ctsb, Ctsd and Ctsl. Each of these gene knockout (KO) and Ctsb;Ctsl and Ctsd;Ctsl double-knockout (DKO) mice were almost normal. However, we found cytoplasmic degeneration in the pancreatic acinar cells of Ctsb;Ctsd DKO mice, similar to autophagy related 5 (Atg5) KO mice. LC3 and p62 (autophagy markers) showed remarkable accumulation and the numbers of autophagosomes and autolysosomes were increased in the pancreatic acinar cells of Ctsb;Ctsd DKO mice. Moreover, these Ctsb;Ctsd DKO mice also developed chronic pancreatitis (CP). Thus, we conclude that both Ctsb and Ctsd deficiency caused impaired autophagy in the pancreatic acinar cells, and induced CP in mice.
ABSTRACT
Craniosynostosis describes conditions in which one or more sutures of the infant skull are prematurely fused, resulting in facial deformity and delayed brain development. Approximately 20% ...of human craniosynostoses are thought to result from gene mutations altering growth factor signaling; however, the molecular mechanisms by which these mutations cause craniosynostosis are incompletely characterized, and the causative genes for diverse types of syndromic craniosynostosis have yet to be identified. Here, we show that enhanced bone morphogenetic protein (BMP) signaling through the BMP type IA receptor (BMPR1A) in cranial neural crest cells, but not in osteoblasts, causes premature suture fusion in mice. In support of a requirement for precisely regulated BMP signaling, this defect was rescued on a Bmpr1a haploinsufficient background, with corresponding normalization of Smad phosphorylation. Moreover, in vivo treatment with LDN‐193189, a selective chemical inhibitor of BMP type I receptor kinases, resulted in partial rescue of craniosynostosis. Enhanced signaling of the fibroblast growth factor (FGF) pathway, which has been implicated in craniosynostosis, was observed in both mutant and rescued mice, suggesting that augmentation of FGF signaling is not the sole cause of premature fusion found in this model. The finding that relatively modest augmentation of Smad‐dependent BMP signaling leads to premature cranial suture fusion suggests an important contribution of dysregulated BMP signaling to syndromic craniosynostoses and potential strategies for early intervention.
Protamines are expressed in the spermatid nucleus and allow denser packaging of DNA compared with histones. Disruption of the coding sequence of one allele of either protamine 1 (Prm1) or Prm2 ...results in failure to produce offspring, although sperm with disrupted Prm1 or Prm2 alleles are produced. Here, we produced Prm1-deficient female chimeric mice carrying Prm1-deficient oocytes. These mice successfully produced Prm1(+/-) male mice. Healthy Prm1(+/-) offspring were then produced by transferring blastocysts obtained via in vitro fertilization using zona-free oocytes and sperm from Prm1(+/-) mice. This result suggests that sperm lacking Prm1 can generate offspring despite being abnormally shaped and having destabilised DNA, decondensed chromatin and a reduction in mitochondrial membrane potential. Nevertheless, these mice showed little derangement of expression profiles.
Objective
Various histological studies of facial pigmented spot sites such as solar lentigo have been reported, but few studies have used quantitative indices by histomorphometric analysis of the ...internal structure of pigmented spot sites using non‐invasive methods. In the present study, to quantitatively elucidate morphological changes in the epidermis in male, darker‐pigmented spots and female, light‐pigmented spots, indices that characterize the internal structure of the epidermis in pigmented spot sites were measured using in vivo confocal laser scanning microscopy (CLSM).
Methods
The darkness of pigmented spots on the cheeks of 69 women and 43 men was analysed using image analysis software. The L* value was calculated from RGB values obtained from facial images. The internal structures of pigmented spots on the cheeks of 13 subjects were observed by CLSM. Various parameters were measured using CLSM images from the surface of the stratum corneum to the bottom of the dermal papillae, including the thickness of the epidermis, melanosome content, and shape of the dermal papillae.
Results
Mean ΔL* values between pigmented spots and non‐pigmented areas of male subjects were significantly increased in the 40s and 50s compared with those of female subjects. Conspicuous pigmented spots increased in the 40s in male subjects and the 50s in female subjects. In CLSM observations, significant increases in the thickness of the epidermis and melanosome content were confirmed in pigmented spots compared with surrounding non‐pigmented areas. In particular, melanosome content in the male subject group with dark‐coloured pigmented spots increased significantly to about eight times that of non‐pigmented areas, and more than double that of the male subject group with light‐coloured pigmented spots.
Conclusion
From the measurements of quantitative parameters, morphological changes in the epidermis were clearly related to the surface colour tone of pigmented spots. Darker pigmented spot sites tended to show longer rete pegs in the epidermis. Accumulation of melanosomes in epidermal basal cells could be considered to increase with the degree of elongation of rete pegs at pigmented spot sites and, thus, induce darker pigmented spots.
Résumé
Objectif
Même si diverses études histologiques des taches pigmentées du visage, tels que les lentigos solaires, ont été publiées, il n'existe que peu d'études ayant utilisé des indices quantitatifs par analyse histomorphométrique de la structure interne des taches pigmentées via des méthodes non invasives. Dans la présente étude, afin d'expliquer quantitativement les changements morphologiques dans l'épiderme des taches pigmentées plus foncées chez l'homme et des taches pigmentées légères chez la femme, les indices qui caractérisent la structure interne de l'épiderme dans les taches pigmentées ont été mesurés par microscopie confocale à balayage laser (MCBL) in vivo.
Méthodes
L'aspect foncé des taches pigmentées sur les joues de 69 femmes et 43 hommes a été analysé à l'aide d'un logiciel d'analyse d'images. La valeur L* a été calculée à partir des valeurs RVB obtenues des images du visage. Sur les joues de 13 sujets, les structures internes des taches pigmentées ont été observées par MCBL. Divers paramètres ont été mesurés à l'aide des images provenant de la MCBL, de la surface de la couche cornée jusqu'au bas des papilles dermiques, y compris l'épaisseur de l'épiderme, la teneur en mélanosome et la forme des papilles dermiques.
Résultats
Les valeurs moyennes de ΔL* entre les zones de taches pigmentées et non pigmentées des hommes ont augmenté de manière significative chez les sujets dans la quarantaine et la cinquantaine par rapport aux valeurs des femmes. Chez les hommes, les taches pigmentées visibles ont augmenté dans la quarantaine, tandis qu'elles ont augmenté dans la cinquantaine chez les femmes. Dans les observations par MCBL, des augmentations significatives de l'épaisseur de l'épiderme et de la teneur en mélanosome ont été confirmées dans les zones de taches pigmentées par rapport aux zones de taches non pigmentées environnantes. Dans le groupe d'hommes présentant des taches pigmentées de couleur foncée en particulier, la teneur en mélanosomes a augmenté de façon significative jusqu'à environ 8 fois celle des zones non pigmentées, et jusqu'à plus du double de celle du groupe d'hommes présentant des taches pigmentées de couleur claire.
Conclusion
D'après les mesures des paramètres quantitatifs, les changements morphologiques dans l'épiderme étaient clairement liés à la couleur à la surface des taches pigmentées. Les sites de taches pigmentées plus foncées montraient généralement des extensions des crêtes épidermiques dans l'épiderme. On pourrait envisager que l'accumulation de mélanosomes dans les cellules basales épidermiques augmente selon le degré d'allongement des crêtes épidermiques au niveau des sites de taches pigmentées, et entraîne ainsi des taches pigmentées plus foncées.
Three‐dimensional stereoscopic images of rete pegs in dark‐colored pigmented spots from males and females constructed from stack images of horizontal sections after the binarization processes. Multiple rete pegs are intertwined to form a large and intricate complex structure in dark‐colored pigmented spots from male subjects. The rete pegs in dark‐colored pigmented spots from female subjects are elongated smoothly and independently.
Background
Although total laryngectomy is the standard treatment for advanced laryngeal cancer, the significance of elective neck dissection (END) for N0 laryngeal cancer remains unclear in Japan, ...which is an aging society.
Methods
We conducted a retrospective nationwide observational study on patients with T3–T4N0 laryngeal squamous cell carcinoma treated with curative total laryngectomy from 2011 to 2018 in Japan.
Results
A total of 1,218 patients were analyzed. The median patient age was 72 years, with 735 cases of T3N0 and 483 cases of T4N0. END was performed on the affected side in 850 patients (70%) and on the contralateral side in 502 patients (41.2%). END on the affected side was omitted in patients aged > 80 years (40.4%) and in patients with an advanced performance status. The occult lymph-node metastasis rate did not differ by age (18.8%–19.6%); it tended to increase chronologically from 2011 (11.1%) and was higher in cT4a (22.5%) and pT4a (24.3%) cases. In this study, coherent clinical information and follow-up data were available for 252 patients. Both univariate and multivariate analyses showed no significant prognostic factors for overall survival or recurrence-free survival for either affected or contralateral END. Older age and subglottic location were poor prognostic factors, but death due to factors other than laryngeal cancer could not be ignored in older patients.
Conclusion
Omission of END during laryngectomy for T3–T4N0 laryngeal cancer is acceptable for older patients who want their operation to be completed in a short time.
Peptidylarginine deiminase 4 (PAD4) functions as a transcriptional coregulator by catalyzing the conversion of histone H3 arginine residues to citrulline residues. Although the high level of PAD4 ...expression in bone marrow cells suggests its involvement in haematopoiesis, its precise contribution remains unclear. Here we show that PAD4, which is highly expressed in lineage(-) Sca-1(+) c-Kit(+) (LSK) cells of mouse bone marrow compared with other progenitor cells, controls c-myc expression by catalyzing the citrullination of histone H3 on its promoter. Furthermore, PAD4 is associated with lymphoid enhancer-binding factor 1 and histone deacetylase 1 at the upstream region of the c-myc gene. Supporting these findings, LSK cells, especially multipotent progenitors, in PAD4-deficient mice show increased proliferation in a cell-autonomous fashion compared with those in wild-type mice. Together, our results strongly suggest that PAD4 regulates the proliferation of multipotent progenitors in the bone marrow by controlling c-myc expression.
Despite the high prevalence of intervertebral disc disease, little is known about changes in intervertebral disc cells and their regenerative potential with ageing and intervertebral disc ...degeneration. Here we identify populations of progenitor cells that are Tie2 positive (Tie2+) and disialoganglioside 2 positive (GD2+), in the nucleus pulposus from mice and humans. These cells form spheroid colonies that express type II collagen and aggrecan. They are clonally multipotent and differentiated into mesenchymal lineages and induced reorganization of nucleus pulposus tissue when transplanted into non-obese diabetic/severe combined immunodeficient mice. The frequency of Tie2+ cells in tissues from patients decreases markedly with age and degeneration of the intervertebral disc, suggesting exhaustion of their capacity for regeneration. However, progenitor cells (Tie2+GD2+) can be induced from their precursor cells (Tie2+GD2-) under simple culture conditions. Moreover, angiopoietin-1, a ligand of Tie2, is crucial for the survival of nucleus pulposus cells. Our results offer insights for regenerative therapy and a new diagnostic standard.
Familial amyloidotic polyneuropathy (FAP) is one of the transthyretin (TTR) amyloidoses characterized by extracellular amyloid deposits and peripheral nerve involvement. Recently, we found ...significant expression of the TTR gene in Schwann cells of the peripheral nervous system. We hypothesized that local expression of variant TTR in Schwann cells may contribute to neurodegeneration in FAP. Schwann cells derived from the dorsal root ganglia (DRG) of transgenic mice expressing variant human TTR in a mouse null background were cultured long term to obtain spontaneously immortalized cell lines. We established an immortalized Schwann cell line, TgS1, derived from the transgenic mice. TgS1 cells synthesized variant TTR and secreted it into the medium. As sensory neuropathy usually arises early in FAP, we examined the effect of the conditioned medium derived from TgS1 cells on neurite outgrowth from DRG sensory neurons. Conditioned medium derived from TgS1 cells inhibited neurite outgrowth from the sensory neurons. TTR deposition in the DRG of aged transgenic mice was investigated by immunohistochemistry. TTR aggregates were observed in the cytoplasm of Schwann cells and satellite cells. Proteasome inhibition induced TTR aggregates as aggresomes in TgS1 cells. In conclusion, local variant TTR gene expression in Schwann cells might trigger neurodegeneration in FAP.
We established a spontaneously immortalized Schwann cell line derived from familial amyloidotic polyneuropathy transgenic mice. Conditioned medium from the cells contained variant transthyretin (TTR), and inhibited neurite outgrowth of neurons. TTR aggregates were observed in the Schwann cells and satellite cells of aged mice. Proteasome inhibition induced TTR aggregates as aggresomes in the cultured cells. These results support the hypothesis that Schwann cells contribute to neurodegeneration in familial amyloidotic polyneuropathy (FAP).
We established a spontaneously immortalized Schwann cell line derived from familial amyloidotic polyneuropathy transgenic mice. Conditioned medium from the cells contained variant transthyretin (TTR), and inhibited neurite outgrowth of neurons. TTR aggregates were observed in the Schwann cells and satellite cells of aged mice. Proteasome inhibition induced TTR aggregates as aggresomes in the cultured cells. These results support the hypothesis that Schwann cells contribute to neurodegeneration in familial amyloidotic polyneuropathy (FAP).
Autophagy is mostly a nonselective bulk degradation system within cells. Recent reports indicate that autophagy can act both as a protector and killer of the cell depending on the stage of the ...disease or the surrounding cellular environment (for review see Cuervo, A.M. 2004. Trends Cell Biol. 14:70-77). We found that cytoplasmic vacuoles induced in pancreatic acinar cells by experimental pancreatitis were autophagic in origin, as demonstrated by microtubule-associated protein 1 light chain 3 expression and electron microscopy experiments. To analyze the role of macroautophagy in acute pancreatitis, we produced conditional knockout mice lacking the autophagy-related 5 gene in acinar cells. Acute pancreatitis was not observed, except for very mild edema in a restricted area, in conditional knockout mice. Unexpectedly, trypsinogen activation was greatly reduced in the absence of autophagy. These results suggest that autophagy exerts devastating effects in pancreatic acinar cells by activation of trypsinogen to trypsin in the early stage of acute pancreatitis through delivering trypsinogen to the lysosome.
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