Discovery of YS-1 as a cell line of gastric inflammatory cancer-associated fibroblasts

BACKGROUND

Inflammatory cancer-associated fibroblasts (iCAFs) was first identified by co-culture of pancreatic stellate cells and tumor organoids. The key feature of iCAFs is IL-6high/αSMAlow. We examine this phenomenon in gastric cancer using two cell lines of gastric fibroblasts (HGF and YS-1).

METHODS AND RESULTS

HGF or YS-1 were co-cultured with MKN7 (a gastric adenocarcinoma cell line) in Matrigel. IL-6 protein levels in the culture supernatant were measured by ELISA. The increased production of IL-6 was not observed in any of the combinations. Instead, the supernatant of YS-1 exhibited the higher levels of IL-6. YS-1 showed IL-6high/αSMA (ACTA2)low in real-time PCR, mRNA-seq and immunohistochemistry. In mRNA-seq, iCAFs-associated genes and signaling pathways were up-regulated in YS-1. No transition to myofibroblastic phenotype was observed by monolayer culture, or the exposure to sonic hedgehog (SHH) or TGF-β. YS-1 conditioned medium induced changes of morphology and stem-ness/differentiation in NUGC-3 (a human gastric adenocarcinoma cell line) and UBE6T-15 (a human bone marrow-derived mesenchymal stem cell line).

CONCLUSIONS

YS-1 is a stable cell line of gastric iCAFs. This discovery will promote further research on iCAFs for many researchers.

Transcription of the Antisense Long Non-Coding RNA, SUPPRESSOR OF FEMINIZATION, Represses Expression of the Female-Promoting Gene FEMALE GAMETOPHYTE MYB in the Liverwort Marchantia polymorpha

Sexual differentiation is a fundamental process in the life cycles of land plants, ensuring successful sexual reproduction and thereby contributing to species diversity and survival. In the dioicous liverwort Marchantia polymorpha, this process is governed by an autosomal sex-differentiation locus comprising FEMALE GAMETOPHYTE MYB (FGMYB), a female-promoting gene, and SUPPRESSOR OF FEMINIZATION (SUF), an antisense strand-encoded long non-coding RNA (lncRNA). SUF is specifically transcribed in male plants and suppresses the expression of FGMYB, leading to male differentiation. However, the molecular mechanisms underlying this process remain elusive. Here, we show that SUF acts through its transcription to suppress FGMYB expression. Transgene complementation analysis using CRISPR/Cas9D10A-based large-deletion mutants identified a genomic region sufficient for the sex differentiation switch function in the FGMYB-SUF locus. Inserting a transcriptional terminator sequence into the SUF-transcribed region resulted in the loss of SUF function and allowed expression of FGMYB in genetically male plants, leading to conversion of the sex phenotype from male to female. Partial deletions of SUF had no obvious impact on its function. Replacement of the FGMYB sequence with that of an unrelated gene did not affect the ability of SUF transcription to suppress sense-strand expression. Taken together, our findings suggest that the process of SUF transcription, rather than the resulting transcripts, is required for controlling sex differentiation in M. polymorpha.

Galectin-3 Plays a Role in Neuroinflammation in the Visual Pathway in Experimental Optic Neuritis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) featuring numerous neuropathologies, including optic neuritis (ON) in some patients. However, the molecular mechanisms of ON remain unknown. Galectins, β-galactoside-binding lectins, are involved in various pathophysiological processes. We previously showed that galectin-3 (gal-3) is associated with the pathogenesis of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. In the current study, we investigated the expression of gal-3 in the visual pathway in EAE mice to clarify its role in the pathogenesis of ON. Immunohistochemical analysis revealed upregulation of gal-3 in the visual pathway of the EAE mice during the peak stage of the disease, compared with naïve and EAE mice during the chronic stage. Gal-3 was detected mainly in microglia/macrophages and astrocytes in the visual pathway in EAE mice. In addition, gal-3+/Iba-1+ cells, identified as phagocytic by immunostaining for cathepsin D, accumulated in demyelinating lesions in the visual pathway during the peak disease stage of EAE. Moreover, NLRP3 expression was detected in most gal-3+/Iba-1+ cells. These results strongly suggest that gal-3 regulates NLRP3 signaling in microglia/macrophages and neuroinflammatory demyelination in ON. In astrocytes, gal-3 was expressed from the peak to the chronic disease stages. Taken together, our findings suggest a critical role of gal-3 in the pathogenesis of ON. Thus, gal-3 in glial cells may serve as a potential therapeutic target for ON.

Association of Regular Cervical Cancer Screening with Socioeconomic, COVID-19 Infection and Vaccine Status Among Japanese Population: Cohort Observational Study

Purpose

Among the Organisation for Economic Co-operation and Development countries, Japan has one of the lowest cervical cancer screening coverages. Cancer screening coverage has worsened due to the coronavirus disease of 2019 (COVID-19) pandemic. This study investigated the relationship between socioeconomic background, COVID-19 infection history and vaccine status, and regular cervical cancer screening (CCS) during the two years of the COVID-19 era in Japan.

Patients and Methods

We used data from the Japan COVID-19 and Society Internet Survey, a nationwide, Internet-based, self-report cohort observational study conducted in 2022. The outcome variable was identified by asking whether the participants had undergone CCS within the last two years. Cervical cytology was performed in Japan by brushing the external cervical os. This study used multivariate log-binomial regression models to evaluate inequalities during regular checkups for CCS. Adjusted prevalence ratios (APRs) with 95% confidence intervals (CIs) were estimated to incorporate the socioeconomic background variables.

Results

Of the 12,066 participants, 5597 (46.4%) had undergone regular CCS for over two years. The prevalence ratio (PR) of patients who underwent CCS was 0.70 for those in their 20s and 0.78 for those in their 60s, compared to those in their 40s. Socioeconomic inequities were found in the following groups: unemployed/student, unmarried, high school graduate or lower, and household income below 4 million Yen. Our final multivariate analysis revealed that participants who were in their 20s or 60s, had a household income below 4 million Yen, were unmarried, had no annual health check-ups, and were unvaccinated with COVID-19 were at a higher risk of not undergoing CCS.

Conclusion

The relationship between socioeconomic inequality and CCS hesitancy is prevalent among younger participants. The CCS coverage in Japan during the COVID-19 pandemic year (2020-2022) was not low compared with the pre-pandemic era.

Mogrol stimulates G-protein-coupled bile acid receptor 1 (GPBAR1/TGR5) and insulin secretion from pancreatic β-cells and alleviates hyperglycemia in mice

Target identification is a crucial step in elucidating the mechanisms by which functional food components exert their functions. Here, we identified the G-protein-coupled bile acid receptor 1 (GPBAR1, also known as TGR5) as a target of the triterpenoid mogrol, a class of aglycone mogroside derivative from Siraitia grosvenorii. Mogrol, but not mogrosides, activated cAMP-response element-mediated transcription in a TGR5-dependent manner. Additionally, mogrol selectively activated TGR5 but not the other bile acid-responsive receptors (i.e., farnesoid X receptor, vitamin D receptor, or muscarinic acetylcholine receptor M3). Several amino acids in TGR5 (L71A2.60, W75AECL1, Q77AECL1, R80AECL1, Y89A3.29, F161AECL2, L166A5.39, Y240A6.51, S247A6.58, Y251A6.62, L262A7.35, and L266A7.39) were found to be important for mogrol-induced activation. Mogrol activated insulin secretion under low-glucose conditions in INS-1 pancreatic β-cells, which can be inhibited by a TGR5 inhibitor. Similar effects of mogrol on insulin secretion were observed in the isolated mouse islets. Mogrol administration partially but significantly alleviated hyperglycemia in KKAy diabetic mice by increasing the insulin levels without affecting the β-cell mass or pancreatic insulin content. These results suggest that mogrol stimulates insulin secretion and alleviates hyperglycemia by acting as a TGR5 agonist.

Cell cycle-dependent activation of proneural transcription factor expression and reactive gliosis in rat Müller glia

Retinal Müller glia have a capacity to regenerate neurons in lower vertebrates like zebrafish, but such ability is extremely limited in mammals. In zebrafish, Müller glia proliferate after injury, which promotes their neurogenic reprogramming while inhibiting reactive gliosis. In mammals, however, how the cell cycle affects the fate of Müller glia after injury remains unclear. Here, we focused on the expression of proneural transcription factors, Ngn2 and Ascl1, and a gliosis marker glial fibrillary acidic protein (GFAP) in rat Müller glia after N-methyl-N-nitrosourea (MNU)-induced photoreceptor injury and analyzed the role of Müller glia proliferation in the regulation of their expression using retinal explant cultures. Thymidine-induced G1/S arrest of Müller glia proliferation significantly hampered the expression of Ascl1, Ngn2, and GFAP, and release from the arrest induced their upregulation. The migration of Müller glia nuclei into the outer nuclear layer was also shown to be cell cycle-dependent. These data suggest that, unlike the situation in zebrafish, cell cycle progression of Müller glia in mammals promotes both neurogenic reprogramming and reactive gliosis, which may be one of the mechanisms underlying the limited regenerative capacity of the mammalian retina.

Creation of High-Performance Heterogeneous Photocatalysts by Controlling Ligand Desorption and Particle Size of Gold Nanocluster

Recently, the creation of new heterogeneous catalysts using the unique electronic/geometric structures of small metal nanoclusters (NCs) has received considerable attention. However, to achieve this, it is extremely important to establish methods to remove the ligands from ligand-protected metal NCs while preventing the aggregation of metal NCs. In this study, the ligand-desorption process during calcination was followed for metal-oxide-supported 2-phenylethanethiolate-protected gold (Au) 25-atom metal NCs using five experimental techniques. The results clearly demonstrate that the ligand-desorption process consists of ligand dissociation on the surface of the metal NCs, adsorption of the generated compounds on the support and desorption of the compounds from the support, and the temperatures at which these processes occurred were elucidated. Based on the obtained knowledge, we established a method to form a metal-oxide layer on the surface of Au NCs while preventing their aggregation, thereby succeeding in creating a water-splitting photocatalyst with high activity and stability.

Effects of activated vitamin D, alfacalcidol, and low-intensity aerobic exercise on osteopenia and muscle atrophy in type 2 diabetes mellitus model rats

Diabetes mellitus causes secondary osteoporosis and muscle atrophy. The ability of alfacalcidol (ALF) and exercise (Exe) to inhibit osteoporosis and muscle atrophy in type 2 diabetes mellitus (T2DM) model rats was examined. Twenty-week-old Otsuka Long-Evans Tokushima Fatty rats were randomized to ALF (orally 0.1 μg/kg/day), Exe (treadmill exercise at 10 m/min, 60 min/day, 5 days/week), Comb (ALF and Exe), and Cont (T2DM control treated with vehicle and no exercise) groups (n = 8–10 per group). Sedentary Long-Evans Tokushima Otsuka rats were used as a non-hyperphagic control. After treatment for 2 or 6 weeks, blood glucose (BG) levels, cross-sectional area (CSA) of tibialis anterior muscle fibers, femoral bone mineral density (BMD), and relative quantities of muscle anabolic markers (Pax7, MyoD, and myogenin) and catabolic markers (Atrogin-1, MuRF1, and REDD1) of the soleus muscle assessed by real-time polymerase chain reaction assays were measured. Exe and Comb treatments for 6 weeks decreased BG levels compared with those of the Cont group. ALF, Exe, and Comb treatments for 2 and 6 weeks recovered the CSA compared with that of the Cont group. ALF and Comb treatments for 6 weeks increased femoral BMDs compared with those of the Cont group. After 2 weeks of treatment, Comb treatment increased MyoD expression and decreased MuRF1 expression. ALF or Exe monotherapy significantly decreased Atrogin-1 or MuRF1 expression after 2 weeks of treatment, respectively. After 6 weeks of treatment, ALF and Comb treatments decreased Atrogin-1 and REDD1. These results demonstrate that a combination of ALF and Exe improved CSA from the early phase of treatment by stimulating skeletal muscle differentiation and suppressing muscle catabolic genes. Improvements in BG, BMD, and CSA were observed as long-term effects of the combination therapy. Continued suppression of muscle catabolic genes was observed as a background to these effects.

Mutations in ParC and GyrA of moxifloxacin-resistant and susceptible Mycoplasma genitalium strains

Macrolide or fluoroquinolone-resistant Mycoplasma genitalium is spreading worldwide. We aimed to determine the influence of single nucleotide polymorphisms (SNPs) in the quinolone resistance determining regions (QRDR) of parC and gyrA in cultured M. genitalium strains. In addition, we examined the prevalence of macrolide- and fluoroquinolone resistance mediating mutations in specimens collected from Japanese male patients with urethritis in two time-periods between 2005–2009 and 2010–2017, respectively, by sequencing the QRDR of parC and gyrA and domain V of the 23S rRNA gene. The minimum inhibitory concentrations (MIC) of moxifloxacin, sitafloxacin, ciprofloxacin, levofloxacin, doxycycline, minocycline, azithromycin and clarithromycin were determined in 23 M. genitalium strains. Three cultured strains had elevated MICs for moxifloxacin at 16, 4 and 2 mg/L and had SNPs with the amino-acid change Ser83→Ile in ParC (p<0.001) and 3 kinds of SNPs with amino-acid changes Asp99→Asn, Gly93→Cys and Met95→Ile in GyrA, respectively. Among a total of 148 M. genitalium positive urine specimens, the prevalence of A2058G and A2059G SNPs in the 23S rRNA gene and any SNPs in ParC increased from 4.8% and 22.6% in 2005–2009 to 42.2% and 53.1% in 2010–2017, respectively. If M. genitalium is considered multi-drug resistant in clinical specimens carrying SNPs in the 23S rRNA gene and Ser83→Ile in ParC, the prevalence of multi-drug resistance is 12.5% in 2010–2017 in Japan. In conclusion, the SNP resulting in Ser83→Ile in ParC is closely related to moxifloxacin resistance even though other factors may also affect treatment outcomes by moxifloxacin. The prevalence of circulating multi-drug resistant M. genitalium strains with macrolide- and fluoroquinolone-resistance is dramatically increasing in Japan.

Prediction of Pneumonia in Acute Stroke Patients Using Tongue Pressure Measurements

Swallowing dysfunction caused by stroke is a risk factor for aspiration pneumonia. Tongue pressure measurement is a simple and noninvasive method for evaluating swallowing dysfunction. We have hypothesized that low tongue pressure may be able to predict pneumonia occurrence in acute stroke patients. Tongue pressure was measured using balloon-type equipment in 220 acute stroke patients. The modified Mann Assessment of Swallowing Ability (MASA) score was evaluated independently on the same day. Tongue pressure was measured every week thereafter. An improvement in tongue pressure was observed within the first 2 weeks. Receiver operating curve analysis was performed to determine the ability of tongue pressure to predict modified MASA score <95, which suggests swallowing dysfunction. The optimal cutoff for tongue pressure was 21.6 kPa (χ2 = 45.82, p<0.001, sensitivity 95.9%, specificity 91.8%, area under the curve = 0.97). The tongue pressure was significantly lower in patients with pneumonia than in those without pneumonia. Using a Cox proportional hazard model for pneumonia onset with a cutoff tongue pressure value of 21.6 kPa and adjustment for age, sex, and National Institutes of Health Stroke Scale score at admission, the tongue pressure had additional predictive power for pneumonia onset (hazard ratio, 7.95; 95% confidence interval, 2.09 to 52.11; p = 0.0013). In the group with low tongue pressure, 27 of 95 patients showed improvement of tongue pressure within 2 weeks. Pneumonia occurred frequently in patients without improvement of tongue pressure, but not in patients with improvement (31/68 and 2/27, p<0.001). Tongue pressure is a sensitive indicator for predicting pneumonia occurrence in acute stroke patients.

Comparison of Drive Counts and Mark-Resight As Methods of Population Size Estimation of Highly Dense Sika Deer (Cervus nippon) Populations

Assessing temporal changes in abundance indices is an important issue in the management of large herbivore populations. The drive counts method has been frequently used as a deer abundance index in mountainous regions. However, despite an inherent risk for observation errors in drive counts, which increase with deer density, evaluations of the utility of drive counts at a high deer density remain scarce. We compared the drive counts and mark-resight (MR) methods in the evaluation of a highly dense sika deer population (MR estimates ranged between 11 and 53 individuals/km2) on Nakanoshima Island, Hokkaido, Japan, between 1999 and 2006. This deer population experienced two large reductions in density; approximately 200 animals in total were taken from the population through a large-scale population removal and a separate winter mass mortality event. Although the drive counts tracked temporal changes in deer abundance on the island, they overestimated the counts for all years in comparison to the MR method. Increased overestimation in drive count estimates after the winter mass mortality event may be due to a double count derived from increased deer movement and recovery of body condition secondary to the mitigation of density-dependent food limitations. Drive counts are unreliable because they are affected by unfavorable factors such as bad weather, and they are cost-prohibitive to repeat, which precludes the calculation of confidence intervals. Therefore, the use of drive counts to infer the deer abundance needs to be reconsidered.