Characterization of the endogenous retrovirus-derived placenta-specific soluble protein EnvV-Fca from domestic cats.

Endogenous retroviruses (ERVs) are remnants of ancestral viruses in the host genome. The present study identified the expression of a defective retroviral env gene belonging to the ERV group V member Env (EnvV) in Felis catus (EnvV-Fca). EnV-Fca was specifically detected in the placental trophoblast syncytiotrophobic layer and expressed as a secreted protein in cultured cells. Genetic analyses indicated that EnvV2 genes are widely present in vertebrates and are under purifying selection among carnivores, suggesting a potential benefit for the host. This study suggests that birds, bats, and rodents carrying EnvV2 may play significant roles as intermediate vectors in spreading or cross-transmitting viruses among species. Our findings provide valuable insights into the evolution of ERV in vertebrate hosts.

FeLIX is a restriction factor for mammalian retrovirus infection.

Endogenous retroviruses (ERVs) are remnants of ancestral viral infections. Feline leukemia virus (FeLV) is an exogenous and endogenous retrovirus in domestic cats. It is classified into several subgroups (A, B, C, D, E, and T) based on viral receptor interference properties or receptor usage. ERV-derived molecules benefit animals, conferring resistance to infectious diseases. However, the soluble protein encoded by the defective envelope (env) gene of endogenous FeLV (enFeLV) functions as a co-factor in FeLV subgroup T infections. Therefore, whether the gene emerged to facilitate viral infection is unclear. Based on the properties of ERV-derived molecules, we hypothesized that the defective env genes possess antiviral activity that would be advantageous to the host because FeLV subgroup B (FeLV-B), a recombinant virus derived from enFeLV env, is restricted to viral transmission among domestic cats. When soluble truncated Env proteins from enFeLV were tested for their inhibitory effects against enFeLV and FeLV-B, they inhibited viral infection. Notably, this antiviral machinery was extended to infection with the Gibbon ape leukemia virus, Koala retrovirus A, and Hervey pteropid gammaretrovirus. Although these viruses used feline phosphate transporter 1 (fePit1) and phosphate transporter 2 as receptors, the inhibitory mechanism involved competitive receptor binding in a fePit1-dependent manner. The shift in receptor usage might have occurred to avoid the inhibitory effect. Overall, these findings highlight the possible emergence of soluble truncated Env proteins from enFeLV as a restriction factor against retroviral infection and will help in developing host immunity and antiviral defense by controlling retroviral spread.IMPORTANCERetroviruses are unique in using reverse transcriptase to convert RNA genomes into DNA, infecting germ cells, and transmitting to offspring. Numerous ancient retroviral sequences are known as endogenous retroviruses (ERVs). The soluble Env protein derived from ERVs functions as a co-factor that assists in FeLV-T infection. However, herein, we show that the soluble Env protein exhibits antiviral activity and provides resistance to mammalian retrovirus infection through competitive receptor binding. In particular, this finding may explain why FeLV-B transmission is not observed among domestic cats. ERV-derived molecules can benefit animals in an evolutionary arms race, highlighting the double-edged-sword nature of ERVs.

Human intestinal organoid-derived PDGFRα + mesenchymal stroma enables proliferation and maintenance of LGR4 + epithelial stem cells.

BACKGROUND: Intestinal epithelial cells derived from human pluripotent stem cells (hPSCs) are generally maintained and cultured as organoids in vitro because they do not exhibit adhesion when cultured. However, the three-dimensional structure of organoids makes their use in regenerative medicine and drug discovery difficult. Mesenchymal stromal cells are found near intestinal stem cells in vivo and provide trophic factors to regulate stem cell maintenance and proliferation, such as BMP inhibitors, WNT, and R-spondin. In this study, we aimed to use mesenchymal stromal cells isolated from hPSC-derived intestinal organoids to establish an in vitro culture system that enables stable proliferation and maintenance of hPSC-derived intestinal epithelial cells in adhesion culture. METHODS: We established an isolation protocol for intestinal epithelial cells and mesenchymal stromal cells from hPSCs-derived intestinal organoids and a co-culture system for these cells. We then evaluated the intestinal epithelial cells and mesenchymal stromal cells' morphology, proliferative capacity, chromosomal stability, tumorigenicity, and gene expression profiles. We also evaluated the usefulness of the cells for pharmacokinetic and toxicity studies. RESULTS: The proliferating intestinal epithelial cells exhibited a columnar form, microvilli and glycocalyx formation, cell polarity, and expression of drug-metabolizing enzymes and transporters. The intestinal epithelial cells also showed barrier function, transporter activity, and drug-metabolizing capacity. Notably, small intestinal epithelial stem cells cannot be cultured in adherent culture without mesenchymal stromal cells and cannot replaced by other feeder cells. Organoid-derived mesenchymal stromal cells resemble the trophocytes essential for maintaining small intestinal epithelial stem cells and play a crucial role in adherent culture. CONCLUSIONS: The high proliferative expansion, productivity, and functionality of hPSC-derived intestinal epithelial cells may have potential applications in pharmacokinetic and toxicity studies and regenerative medicine.

Multiple recombination events between endogenous retroviral elements and feline leukemia virus.

Feline leukemia virus (FeLV) is an exogenous retrovirus that causes malignant hematopoietic disorders in domestic cats, and its virulence may be closely associated with viral sequences. FeLV is classified into several subgroups, including A, B, C, D, E, and T, based on viral receptor interference properties or receptor usage. However, the transmission manner and disease specificity of the recombinant viruses FeLV-D and FeLV-B remain unclear. The aim of this study was to understand recombination events between exogenous and endogenous retroviruses within a host and elucidate the emergence and transmission of recombinant viruses. We observed multiple recombination events involving endogenous retroviruses (ERVs) in FeLV from a family of domestic cats kept in one house; two of these cats (ON-T and ON-C) presented with lymphoma and leukemia, respectively. Clonal integration of FeLV-D was observed in the ON-T case, suggesting an association with FeLV-D pathogenesis. Notably, the receptor usage of FeLV-B observed in ON-T was mediated by feline Pit1 and feline Pit2, whereas only feline Pit1 was used in ON-C. Furthermore, XR-FeLV, a recombinant FeLV containing an unrelated sequence referred to the X-region, which is homologous to a portion of the 5'-leader sequence of Felis catus endogenous gammaretrovirus 4 (FcERV-gamma4), was isolated. Genetic analysis suggested that most recombinant viruses occurred de novo; however, the possibility of FeLV-B transmission was also recognized in the family. This study demonstrated the occurrence of multiple recombination events between exogenous and endogenous retroviruses in domestic cats, highlighting the contribution of ERVs to pathogenic recombinant viruses.IMPORTANCEFeline leukemia virus subgroup A (FeLV-A) is primarily transmitted among cats. During viral transmission, genetic changes in the viral genome lead to the emergence of novel FeLV subgroups or variants with altered virulence. We isolated three FeLV subgroups (A, B, and D) and XR-FeLV from two cats and identified multiple recombination events in feline endogenous retroviruses (ERVs), such as enFeLV, ERV-DC, and FcERV-gamma4, which are present in the cat genome. This study highlights the pathogenic contribution of ERVs in the emergence of FeLV-B, FeLV-D, and XR-FeLV in a feline population.

Drug metabolic activity as a selection factor for pluripotent stem cell-derived hepatic progenitor cells.

As a metabolic organ, the liver plays a variety of roles, including detoxification. It has been difficult to obtain stable supplies of hepatocytes for transplantation and for accurate hepatotoxicity determination in drug discovery research. Human pluripotent stem cells, capable of unlimited self-renewal, may be a promising source of hepatocytes. In order to develop a stable supply of embryonic stem cell (ESC)-derived hepatocytes, we have purified human ESC-derived hepatic progenitor cells with exposure to cytocidal puromycin by using their ability to metabolize drugs. Hepatic progenitor cells stably proliferated at least 220-fold over 120 days, maintaining hepatic progenitor cell-like properties. High drug-metabolizing hepatic progenitor cells can be matured into liver cells by suppressing hepatic proliferative signals. The method we developed enables the isolation and proliferation of functional hepatic progenitors from human ESCs, thereby providing a stable supply of high-quality cell resources at high efficiency. Cells produced by this method may facilitate cell therapy for hepatic diseases and reliable drug discovery research.

Case report on successful treatment for brain abscess in a Japanese monkey (Macaca fuscata).

BACKGROUND: A brain abscess in human beings is a focal infection of the central nervous system frequently characterized by areas of localized cerebritis and central necrosis surrounded by a well vascularized capsule. A brain abscess, although sporadically reported, is relatively rare disease in domestic animals (horses, cattle, goats and alpacas), companion animals (dogs and cats) and laboratory nonhuman primates. Brain abscesses are life threatening disease that needs early and aggressive veterinary therapy. CASE PRESENTATION: The purpose of this study on a brain abscess in a Japanese monkey was to report the investigational and therapeutic processes including clinical observations, hematological and serum biochemical profiles, and magnetic resonance imaging (MRI) features, probiotic and antibiotic therapy. In clinical observation, the monkey presented with slowly progressive gentle and depressed behavioral change. Hematological findings showed that slightly declined platelet counts gradually increased in the course of the treatment. Serum biochemical profiles revealed initial markedly elevated. A series of chemotherapy provide prominent relief from the influence of the brain abscess. MRI images illustrated that a brain abscess was located in the right frontal lobe and the mass was delineated by a thick rim, indicating the capsule formation stage. The lesion chronologically decreased in size over the course of treatment. Until 11 weeks after treatment of the brain abscess, the size of brain abscess continued to reduce, leaving an organized lesion trace. To the best of my knowledge, this is the first report on successful treatment for a brain abscess in a Japanese monkey (Macaca fuscata). CONCLUSIONS: Medical management of simian brain abscesses is possible based on the controlled and resolving nature of the lesions as determined by MRI and completion of a of chemical antibiotic treatment presented in this study.

Spatiotemporal changes of tissue glycans depending on localization in cardiac aging.

Heart failure is caused by various factors, making the underlying pathogenic mechanisms difficult to identify. Since cardiovascular disease tends to worsen over time, early diagnosis is key for treatment. In addition, understanding the qualitative changes in the heart associated with aging, where information on the direct influences of aging on cardiovascular disease is limited, would also be useful for treatment and diagnosis. To fill these research gaps, the focus of our study was to detect the structural and functional molecular changes associated with the heart over time, with a focus on glycans, which reflect the type and state of cells. METHODS: We investigated glycan localization in the cardiac tissue of normal mice and their alterations during aging, using evanescent-field fluorescence-assisted lectin microarray, a technique based on lectin-glycan interaction, and lectin staining. RESULTS: The glycan profiles in the left ventricle showed differences between the luminal side (medial) and wall side (lateral) regions. The medial region was characterized by the presence of sialic acid residues. Moreover, age-related changes in glycan profiles were observed at a younger age in the medial region. The difference in the age-related decrease in the level of α-galactose stained with Griffonia simplicifolia lectin-IB4 in different regions of the left ventricle suggests spatiotemporal changes in the number of microvessels. CONCLUSIONS: The glycan profile, which retains diverse glycan structures, is supported by many cell populations, and maintains cardiac function. With further research, glycan localization and changes have the potential to be developed as a marker of the signs of heart failure.

Genetic variation in the Y chromosome and sex-biased DNA methylation in somatic cells in the mouse.

Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on autosomal DNA methylation patterns and its contribution to sex bias in methylation, we identified Y chromosome dependent differentially methylated regions (yDMRs) using whole-genome bisulfite sequencing methylation data from livers of mice with different combinations of sex-chromosome complement and gonadal sex. Nearly 90% of the autosomal yDMRs mapped to transposable elements (TEs) and most of them had lower methylation in XY compared to XX or XO mice. Follow-up analyses of four reporter autosomal yDMRs showed that Y-dependent methylation levels were consistent across most somatic tissues but varied in strains with different origins of the Y chromosome, suggesting that genetic variation in the Y chromosome influenced methylation levels of autosomal regions. Mice lacking the q-arm of the Y chromosome (B6.NPYq-2) as well as mice with a loss-of-function mutation in Kdm5d showed no differences in methylation levels compared to wild type mice. In conclusion, the Y-linked modifier of TE methylation is likely to reside on the short arm of Y chromosome and further studies are required to identify this gene.

Clinical utility of intraductal carcinoma of the prostate in treatment selection for metastatic hormone-sensitive prostate cancer.

BACKGROUND: In recent years, the usefulness of androgen receptor axis-targeted agents (ARATs) such as abiraterone, enzalutamide, and apalutamide for the upfront treatment of metastatic hormone-sensitive prostate cancer (mHSPC) has been demonstrated. However, it remains unclear which patients would truly benefit from these treatments. Furthermore, intraductal carcinoma of the prostate (IDC-P) is a known poor prognostic factor in patients with prostate cancer. We investigated the association between the presence of IDC-P and response to therapy in patients with mHSPC. METHODS: This retrospective analysis included 318 patients with mHSPC who received treatment at Nagoya University and its 12 affiliated institutions between 2014 and 2021. Their biopsy specimens were evaluated for the presence of IDC-P. The patients were classified according to their first-line treatment into the ARAT (n = 100, receiving a combination of androgen-deprivation therapy [ADT] and ARAT) or conventional therapy (n = 218, receiving ADT with or without standard antiandrogen agents) group. We compared the overall survival (OS) and second progression-free survival (PFS2) between the ARAT and conventional groups according to the presence of IDC-P to evaluate whether presence of IDC-P predicts the response to each treatment. PFS2 was defined as the period from mHSPC diagnosis to disease progression on second-line treatment or death. Propensity score matching with one-to-one nearest-neighbor matching was used to minimize the potential effects of selection bias and confounding factors. The clinicopathological variables of the patients were well-balanced after propensity score matching. RESULTS: Most patients in the ARAT (79%) and conventional therapy (71%) groups were ICD-P positive. In the propensity score-matched cohort, the OS and PFS2 of IDC-P-positive patients were significantly longer in the ARAT group than in the conventional group (OS: hazard ratio [HR], 0.36; p = 0.047; PFS2: HR, 0.30; p < 0.001). In contrast, no difference in OS and PFS2 was observed between the ARAT and conventional groups in IDC-P-negative patients (OS: HR, 1.09; p = 0.920; PFS2: HR, 0.40; p = 0.264). CONCLUSIONS: The findings highlight a high prevalence of IDC-P among patients with mHSPC and suggest that IDC-P positivity may be a reliable indicator that ARAT should be implemented as first-line treatment.

Switching defective/sucrose non-fermenting chromatin remodeling complex coordinates meiotic gene activation via promoter remodeling and Meiosin activation in female germline.

In mammals, primordial germ cells (PGCs) enter meiosis and differentiate into primary oocytes in embryonic ovaries. Previously, we demonstrated that meiotic gene induction and meiotic initiation were impaired in female germline cells of conditional knockout (CKO) mice lacking the Smarcb1 (Snf5) gene, which encodes a core subunit of the switching defective/sucrose non-fermenting (SWI/SNF) complex. In this study, we classified meiotic genes expressed at lower levels in Snf5 CKO females into two groups based on promoter accessibility. The promoters of 74% of these genes showed lower accessibility in mutant mice, whereas those of the remaining genes were opened without the SWI/SNF complex. Notably, the former genes included Meiosin, which encodes a transcriptional regulator essential for meiotic gene activation. The promoters of the former and the latter genes were mainly modified with H3K27me3/bivalent and H3K4me3 histone marks, respectively. A subset of the former genes was precociously activated in female PGCs deficient in polycomb repressive complexes (PRCs). Our results point to a mechanism through which the SWI/SNF complex coordinates meiotic gene activation via the remodeling of PRC-repressed genes, including Meiosin, in female germline cells.

Trichoblastomas derived from the facial skin with tactile hair in aged house musk shrews (Suncus murinus).

BACKGROUND: Benign hair follicle tumors are relatively rare cutaneous neoplasms arising from hair follicle differentiation. These tumors are slow-growing solitary papules or nodules in the head, face or neck. The aim of this study was to describe 2 cases of trichoblastomas in tactile hair skin incidentally encountered in aged house musk shrews (Suncus murinus). In addition, this case report clarifies whether the characteristics in the tactile hair skin of Suncus murinus are different from those in humans and other animals. CASE PRESENTATION: The animals were investigated the characteristics of the clinical findings, hematological and serum biochemical profiles (particularly, serum amyloid A levels (vSAA)), and histopathological results. Suncus murinus with the facial tumor showed weight loss and coarse fur. Hematological examinations indicated microcytic and normochromic anemia. Although few apparent changes were serum biochemically found in Suncus murinus, vSAA levels moderately increased and revealed inflammatory reactions. These lesions histopathologically showed the basaloid islands comprising peripheral palisading and dilated microcysts containing variable admixtures of free-floating cells such as neoplasm cells, giant cells, clear cells, mononuclear cells and erythrocytes. CONCLUSIONS: The author concluded that trichoblastomas in Suncus murinus revealed growth and morphological characteristics that recapitulate part of embryological development in the tactile hair follicles. In the histological structure, their trichoblastomas in the tactile hair skin were different from those found in humans and animals such as cats, dogs and other wildlife.

Hot spring bathing accelerates wound healing and enhances heat retention effect in guinea pigs.

This study aimed to demonstrate the effects of hot springs on wound healing and heat retention by performing comparative experiments with tap water. The hot spring water used in this study was from an alkaline hot spring that was rich in sodium and chloride ions and exhibited high reducibility. Guinea pigs were divided into a hot spring bathing group and a tap water bathing group, and a bathing test was conducted for eight consecutive days. A comparison of the plasma amino acid composition between the two groups after the bathing test revealed differences in the concentrations of several amino acids associated with wound healing. Image analysis demonstrated that wounds made on the abdominal skin of guinea pigs were significantly contracted by hot spring bathing compared to that by tap water bathing, and histopathological findings showed that wound healing was accelerated. In the thermography test, changes in body surface temperature after bathing were investigated in both groups. The heat retention effect was not observed in the tap water bathing group after bathing, whereas it was enhanced in the hot spring bathing group until 30 min after bathing. In conclusion, this study demonstrated that hot spring bathing accelerates wound healing and has a more significant heat retention effect than tap water bathing.

Epigenome editing reveals core DNA methylation for imprinting control in the Dlk1-Dio3 imprinted domain.

The Dlk1-Dio3 imprinted domain is controlled by an imprinting control region (ICR) called IG-DMR that is hypomethylated on the maternal allele and hypermethylated on the paternal allele. Although several genetic mutation experiments have shown that IG-DMR is essential for imprinting control of the domain, how DNA methylation itself functions has not been elucidated. Here, we performed both gain and loss of DNA methylation experiments targeting IG-DMR by transiently introducing CRISPR/Cas9 based-targeted DNA methylation editing tools along with one guide RNA into mouse ES cells. Altered DNA methylation, particularly at IG-DMR-Rep, which is a tandem repeat containing ZFP57 methylated DNA-binding protein binding motifs, affected the imprinting state of the whole domain, including DNA methylation, imprinted gene expression, and histone modifications. Moreover, the altered imprinting states were persistent through neuronal differentiation. Our results suggest that the DNA methylation state at IG-DMR-Rep, but not other sites in IG-DMR, is a master element to determine whether the allele behaves as the intrinsic maternal or paternal allele. Meanwhile, this study provides a robust strategy and methodology to study core DNA methylation in cis-regulatory elements, such as ICRs and enhancers.

Drug metabolic activity is a critical cell-intrinsic determinant for selection of hepatocytes during long-term culture.

BACKGROUND: The liver plays an important role in various metabolic processes, including protein synthesis, lipid and drug metabolisms and detoxifications. Primary culture of hepatocytes is used for the understanding of liver physiology as well as for the drug development. Hepatocytes are, however, hardly expandable in vitro making it difficult to secure large numbers of cells from one donor. Alternatively, systems using animal models and hepatocellular carcinoma cells have been established, but interspecies differences, variation between human cell sources and limited hepatic functions are among the challenges faced when using these models. Therefore, there is still a need for a highly stable method to purify human hepatocytes with functional sufficiency. In this study, we aimed to establish an in vitro long-term culture system that enables stable proliferation and maintenance of human hepatocytes to ensure a constant supply. METHODS: We first established a growth culture system for hepatocytes derived from patients with drug-induced liver injury using fetal mouse fibroblasts and EMUKK-05 medium. We then evaluated the morphology, proliferative capacity, chromosome stability, gene and protein expression profiles, and drug metabolic capacity of hepatocytes in early, middle and late passages with and without puromycin. In addition, hepatic maturation in 3D culture was evaluated from morphological and functional aspects. RESULTS: In our culture system, the stable proliferation of human hepatocytes was achieved by co-culturing with mouse fetal fibroblasts, resulting in dedifferentiation into hepatic progenitor-like cells. We purified human hepatocytes by selection with cytocidal puromycin and cultured them for more than 60 population doublings over a span of more than 350 days. Hepatocytes with high expression of cytochrome P450 genes survived after exposure to cytocidal antibiotics because of enhanced drug-metabolizing activity. CONCLUSIONS: These results show that this simple culture system with usage of the cytocidal antibiotics enables efficient hepatocyte proliferation and is an effective method for generating a stable supply of hepatocytes for drug discovery research at a significant cost reduction.

Spontaneous Polycystic Kidneys with Chronic Renal Failure in an Aged House Musk Shrew (Suncus murinus).

Polycystic kidney disease is one of the most common inheritable renal diseases, characterized by the formation of multiple fluid-filled renal cysts. This disease is a progressive and unfortunately incurable condition. A case of polycystic kidney with chronic renal failure in house musk shrew (Suncus murinus) is described. At clinical presentation, a 16-month-old Suncus murinus showed weight loss and coarse fur. Regarding the biochemical profile, total protein concentrations increased, resulting in a declined albumin: globulin ratio. Blood urea nitrogen and creatinine concentrations were markedly elevated, indicating the end stage of chronic renal failure. Serum amyloid A levels increased and revealed inflammatory reaction during the cyst formation. Histopathologically, multiple cysts were lined by a single layer of epithelial cells or low cuboidal epithelium. The contents were homogenous eosinophilic materials (mucopolysaccharides or mucoproteins) and these cysts contained abundant macrophages. There were also regeneration and dilatation of renal tubes and interstitial fibrosis. The atrophic glomeruli and glomerular capsules were thickened and hyalinized by dense amorphous mucopolysaccharides. These histopathological findings suggested that the pathogenesis of polycystic kidney disease shared a common mechanistic feature across species.

Puromycin-based purification of cells with high expression of the cytochrome P450 CYP3A4 gene from a patient with drug-induced liver injury (DILI).

BACKGROUND: Many drugs have the potential to induce the expression of drug-metabolizing enzymes, particularly cytochrome P450 3A4 (CYP3A4), in hepatocytes. Hepatocytes can be accurately evaluated for drug-mediated CYP3A4 induction; this is the gold standard for in vitro hepatic toxicology testing. However, the variation from lot to lot is an issue that needs to be addressed. Only a limited number of immortalized hepatocyte cell lines have been reported. In this study, immortalized cells expressing CYP3A4 were generated from a patient with drug-induced liver injury (DILI). METHODS: To generate DILI-derived cells with high expression of CYP3A4, a three-step approach was employed: (1) Differentiation of DILI-induced pluripotent stem cells (DILI-iPSCs); (2) Immortalization of the differentiated cells; (3) Selection of the cells by puromycin. It was hypothesized that cells with high cytochrome P450 gene expression would be able to survive exposure to cytotoxic antibiotics because of their increased drug-metabolizing activity. Puromycin, a cytotoxic antibiotic, was used in this study because of its rapid cytocidal effect at low concentrations. RESULTS: The hepatocyte-like cells differentiated from DILI-iPSCs were purified by exposure to puromycin. The puromycin-selected cells (HepaSM or SI cells) constitutively expressed the CYP3A4 gene at extremely high levels and exhibited hepatocytic features over time. However, unlike primary hepatocytes, the established cells did not produce bile or accumulate glycogen. CONCLUSIONS: iPSC-derived hepatocyte-like cells with intrinsic drug-metabolizing enzymes can be purified from non-hepatocytes and undifferentiated iPSCs using the cytocidal antibiotic puromycin. The puromycin-selected hepatocyte-like cells exhibited characteristics of hepatocytes after immortalization and may serve as another useful source for in vitro hepatotoxicity testing of low molecular weight drugs.

SWI/SNF chromatin remodeling complex is required for initiation of sex-dependent differentiation in mouse germline.

Sexual reproduction involves the creation of sex-dependent gametes, oocytes and sperm. In mammals, sexually dimorphic differentiation commences in the primordial germ cells (PGCs) in embryonic gonads; PGCs in ovaries and testes differentiate into meiotic primary oocytes and mitotically quiescent prospermatogonia, respectively. Here, we show that the transition from PGCs to sex-specific germ cells was abrogated in conditional knockout mice carrying a null mutation of Smarcb1 (also known as Snf5) gene, which encodes a core subunit of the SWI/SNF chromatin remodeling complex. In female mutant mice, failure to upregulate meiosis-related genes resulted in impaired meiotic entry and progression, including defects in synapsis formation and DNA double strand break repair. Mutant male mice exhibited delayed mitotic arrest and DNA hypomethylation in retrotransposons and imprinted genes, resulting from aberrant expression of genes related to growth and de novo DNA methylation. Collectively, our results demonstrate that the SWI/SNF complex is required for transcriptional reprogramming in the initiation of sex-dependent differentiation of germ cells.

Comfortable and dermatological effects of hot spring bathing provide demonstrative insight into improvement in the rough skin of Capybaras.

The purpose of this study was to clarify dermatologically the favorable effects of hot spring bathing on the rough skin in Capybaras. Non-volcanic hot springs used in this study showed alkaline quality of water (pH 9.3), containing sodium and chloride ions. The normal skin in Capybaras was characterized by the presence of relatively thick epidermis with mild alkaline state (pH 8.26). The dorsal skin had melanin granules in the basal layer. Their rough skin affected in the Japanese cold winter was improved by daily bathing in an alkaline hot spring. The skin properties returned to the normal skin conditions (moisture, melanin and erythema values) observed in the summer. The facial expression mainly changes in the eyes was scored to evaluate comfortable status. The comfortable status during hot spring bathing significantly increased as compared with that observed before bathing (p < 0.01). The thermography revealed a heat retention effect of body temperature after hot spring bathing for 30 min. In conclusion, this study demonstrates that hot spring had significantly comfortable and dermatological effects on the basis of evaluation for the skin and body conditions in Capybaras.

Demonstrative Experiment on the Favorable Effects of Static Electric Field Treatment on Vitamin D3-Induced Hypercalcemia.

The purpose of this study was to elucidate the effects of static electric field (SEF) treatment on vitamin D3 (Vit D3)-induced hypercalcemia and renal calcification in mice. The mice were assigned to three groups: Vit D3-treated mice, mice treated with Vit D3 and SEF (Vit D3 + SEF), and untreated mice. After the administration of Vit D3, the Vit D3 + SEF-treated mice were exposed to SEF treatment by a high-voltage alternating current over five days. Serum biochemical examinations revealed that both the creatinine and blood urea nitrogen concentrations were significantly higher in the Vit D3-treated group. Significantly, decreased Cl concentrations, and increased Ca and inorganic phosphorus concentrations, were found in the Vit D3-treated group. In the Vit D3 + SEF-treated group, these parameters returned to the levels of the untreated group. In the Vit D3-treated group, histopathological examinations showed marked multifocal calcification in the lumens of the renal tubules and the renal parenchyma. The myocardium was replaced by abundant granular mineralization (calcification), with degeneration and necrosis of the calcified fibers. The stomach showed calcification of the cardiac mucosa. SEF treatment remarkably attenuated the Vit D3-induced hypervitaminotic injuries. In conclusion, this study provides important evidence that SEF treatment can reduce hypercalcemia and remove calcium deposits from the renal, cardiac, and gastric tissues. SEF treatment is useful in the regulation of disorders caused by an imbalance of serum electrolytes.

AKT signaling is associated with epigenetic reprogramming via the upregulation of TET and its cofactor, alpha-ketoglutarate during iPSC generation.

BACKGROUND: Phosphoinositide-3 kinase (PI3K)/AKT signaling participates in cellular proliferation, survival and tumorigenesis. The activation of AKT signaling promotes the cellular reprogramming including generation of induced pluripotent stem cells (iPSCs) and dedifferentiation of primordial germ cells (PGCs). Previous studies suggested that AKT promotes reprogramming by activating proliferation and glycolysis. Here we report a line of evidence that supports the notion that AKT signaling is involved in TET-mediated DNA demethylation during iPSC induction. METHODS: AKT signaling was activated in mouse embryonic fibroblasts (MEFs) that were transduced with OCT4, SOX2 and KLF4. Multiomics analyses were conducted in this system to examine the effects of AKT activation on cells undergoing reprogramming. RESULTS: We revealed that cells undergoing reprogramming with artificially activated AKT exhibit enhanced anabolic glucose metabolism and accordingly increased level of cytosolic α-ketoglutarate (αKG), which is an essential cofactor for the enzymatic activity of the 5-methylcytosine (5mC) dioxygenase TET. Additionally, the level of TET is upregulated. Consistent with the upregulation of αKG production and TET, we observed a genome-wide increase in 5-hydroxymethylcytosine (5hmC), which is an intermediate in DNA demethylation. Moreover, the DNA methylation level of ES-cell super-enhancers of pluripotency-related genes is significantly decreased, leading to the upregulation of associated genes. Finally, the transduction of TET and the administration of cell-permeable αKG to somatic cells synergistically enhance cell reprogramming by Yamanaka factors. CONCLUSION: These results suggest the possibility that the activation of AKT during somatic cell reprogramming promotes epigenetic reprogramming through the hyperactivation of TET at the transcriptional and catalytic levels.