Amphiregulin Switches Progenitor Cell Fate for Lineage Commitment During Gastric Mucosal Regeneration.

BACKGROUND & AIMS: Isthmic progenitors, tissue-specific stem cells in the stomach corpus, maintain mucosal homeostasis by balancing between proliferation and differentiation to gastric epithelial lineages. The progenitor cells rapidly adopt an active state in response to mucosal injury. However, it remains unclear how the isthmic progenitor cell niche is controlled during the regeneration of damaged epithelium. METHODS: We recapitulated tissue recovery process after acute mucosal injury in the mouse stomach. Bromodeoxyuridine incorporation was used to trace newly generated cells during the injury and recovery phases. To define the epithelial lineage commitment process during recovery, we performed single-cell RNA-sequencing on epithelial cells from the mouse stomachs. We validated the effects of amphiregulin (AREG) on mucosal recovery, using recombinant AREG treatment or AREG-deficient mice. RESULTS: We determined that an epidermal growth factor receptor ligand, AREG, can control progenitor cell lineage commitment. Based on the identification of lineage-committed subpopulations in the corpus epithelium through single-cell RNA-sequencing and bromodeoxyuridine incorporation, we showed that isthmic progenitors mainly transition into short-lived surface cell lineages but are less frequently committed to long-lived parietal cell lineages in homeostasis. However, mucosal regeneration after damage directs the lineage commitment of isthmic progenitors towards parietal cell lineages. During recovery, AREG treatment promoted repopulation with parietal cells, while suppressing surface cell commitment of progenitors. In contrast, transforming growth factor-α did not alter parietal cell regeneration, but did induce expansion of surface cell populations. AREG deficiency impairs parietal cell regeneration but increases surface cell commitment. CONCLUSIONS: These data demonstrate that different epidermal growth factor receptor ligands can distinctly regulate isthmic progenitor-driven mucosal regeneration and lineage commitment.

Targeting Stem Cells and Dysplastic Features With Dual MEK/ERK and STAT3 Suppression in Gastric Carcinogenesis.

BACKGROUNDS & AIMS: Precancerous metaplasia progression to dysplasia can increase the risk of gastric cancers. However, effective strategies to specifically target these precancerous lesions are currently lacking. To address this, we aimed to identify key signaling pathways that are upregulated during metaplasia progression and critical for stem cell survival and function in dysplasia. METHODS: To assess the response to chemotherapeutic drugs, we used metaplastic and dysplastic organoids derived from Mist1-Kras mice and 20 human precancerous organoid lines established from patients with gastric cancer. Phospho-antibody array analysis and single-cell RNA-sequencing were performed to identify target cell populations and signaling pathways affected by pyrvinium, a putative anticancer drug. Pyrvinium was administered to Mist1-Kras mice to evaluate drug effectiveness in vivo. RESULTS: Although pyrvinium treatment resulted in growth arrest in metaplastic organoids, it induced cell death in dysplastic organoids. Pyrvinium treatment significantly downregulated phosphorylation of ERK and signal transducer and activator of transcription 3 (STAT3) as well as STAT3-target genes. Single-cell RNA-sequencing data analyses revealed that pyrvinium specifically targeted CD133+/CD166+ stem cell populations, as well as proliferating cells in dysplastic organoids. Pyrvinium inhibited metaplasia progression and facilitated the restoration of normal oxyntic glands in Mist1-Kras mice. Furthermore, pyrvinium exhibited suppressive effects on the growth and survival of human organoids with dysplastic features, through simultaneous blocking of the MEK/ERK and STAT3 signaling pathways. CONCLUSIONS: Through its dual blockade of MEK/ERK and STAT3 signaling pathways, pyrvinium can effectively induce growth arrest in metaplasia and cell death in dysplasia. Therefore, our findings suggest that pyrvinium is a promising chemotherapeutic agent for reprogramming the precancerous milieu to prevent gastric cancer development.

Oncogenic Fatty Acid Metabolism Rewires Energy Supply Chain in Gastric Carcinogenesis.

BACKGROUND & AIMS: Gastric carcinogenesis develops within a sequential carcinogenic cascade from precancerous metaplasia to dysplasia and adenocarcinoma, and oncogenic gene activation can drive the process. Metabolic reprogramming is considered a key mechanism for cancer cell growth and proliferation. However, how metabolic changes contribute to the progression of metaplasia to dysplasia remains unclear. We have examined metabolic dynamics during gastric carcinogenesis using a novel mouse model that induces Kras activation in zymogen-secreting chief cells. METHODS: We generated a Gif-rtTA;TetO-Cre;KrasG12D (GCK) mouse model that continuously induces active Kras expression in chief cells after doxycycline treatment. Histologic examination and imaging mass spectrometry were performed in the GCK mouse stomachs at 2 to 14 weeks after doxycycline treatment. Mouse and human gastric organoids were used for metabolic enzyme inhibitor treatment. The GCK mice were treated with a stearoyl- coenzyme A desaturase (SCD) inhibitor to inhibit the fatty acid desaturation. Tissue microarrays were used to assess the SCD expression in human gastrointestinal cancers. RESULTS: The GCK mice developed metaplasia and high-grade dysplasia within 4 months. Metabolic reprogramming from glycolysis to fatty acid metabolism occurred during metaplasia progression to dysplasia. Altered fatty acid desaturation through SCD produces a novel eicosenoic acid, which fuels dysplastic cell hyperproliferation and survival. The SCD inhibitor killed both mouse and human dysplastic organoids and selectively targeted dysplastic cells in vivo. SCD was up-regulated during carcinogenesis in human gastrointestinal cancers. CONCLUSIONS: Active Kras expression only in gastric chief cells drives the full spectrum of gastric carcinogenesis. Also, oncogenic metabolic rewiring is an essential adaptation for high-energy demand in dysplastic cells.

Prioritizing susceptibility genes for the prognosis of male-pattern baldness with transcriptome-wide association study.

BACKGROUND: Male-pattern baldness (MPB) is the most common cause of hair loss in men. It can be categorized into three types: type 2 (T2), type 3 (T3), and type 4 (T4), with type 1 (T1) being considered normal. Although various MPB-associated genetic variants have been suggested, a comprehensive study for linking these variants to gene expression regulation has not been performed to the best of our knowledge. RESULTS: In this study, we prioritized MPB-related tissue panels using tissue-specific enrichment analysis and utilized single-tissue panels from genotype-tissue expression version 8, as well as cross-tissue panels from context-specific genetics. Through a transcriptome-wide association study and colocalization analysis, we identified 52, 75, and 144 MPB associations for T2, T3, and T4, respectively. To assess the causality of MPB genes, we performed a conditional and joint analysis, which revealed 10, 11, and 54 putative causality genes for T2, T3, and T4, respectively. Finally, we conducted drug repositioning and identified potential drug candidates that are connected to MPB-associated genes. CONCLUSIONS: Overall, through an integrative analysis of gene expression and genotype data, we have identified robust MPB susceptibility genes that may help uncover the underlying molecular mechanisms and the novel drug candidates that may alleviate MPB.

Apposition of Fibroblasts With Metaplastic Gastric Cells Promotes Dysplastic Transition.

BACKGROUND & AIMS: Elements of field cancerization, including atrophic gastritis, metaplasia, and dysplasia, promote gastric cancer development in association with chronic inflammation. However, it remains unclear how stroma changes during carcinogenesis and how the stroma contributes to progression of gastric preneoplasia. Here we investigated heterogeneity of fibroblasts, one of the most important elements in the stroma, and their roles in neoplastic transformation of metaplasia. METHODS: We used single-cell transcriptomics to evaluate the cellular heterogeneity of mucosal cells from patients with gastric cancer. Tissue sections from the same cohort and tissue microarrays were used to identify the geographical distribution of distinct fibroblast subsets. We further evaluated the role of fibroblasts from pathologic mucosa in dysplastic progression of metaplastic cells using patient-derived metaplastic gastroids and fibroblasts. RESULTS: We identified 4 subsets of fibroblasts within stromal cells defined by the differential expression of PDGFRA, FBLN2, ACTA2, or PDGFRB. Each subset was distributed distinctively throughout stomach tissues with different proportions at each pathologic stage. The PDGFRα+ subset expanded in metaplasia and cancer compared with normal, maintaining a close proximity with the epithelial compartment. Co-culture of metaplasia- or cancer-derived fibroblasts with gastroids showing the characteristics of spasmolytic polypeptide-expressing metaplasia-induced disordered growth, loss of metaplastic markers, and increases in markers of dysplasia. Culture of metaplastic gastroids with conditioned media from metaplasia- or cancer-derived fibroblasts also promoted dysplastic transition. CONCLUSIONS: These findings indicate that fibroblast associations with metaplastic epithelial cells can facilitate direct transition of metaplastic spasmolytic polypeptide-expressing metaplasia cell lineages into dysplastic lineages.

A developmental lineage-based gene co-expression network for mouse pancreatic ß-cells reveals a role for Zfp800 in pancreas development.

To gain a deeper understanding of pancreatic ß-cell development, we used iterative weighted gene correlation network analysis to calculate a gene co-expression network (GCN) from 11 temporally and genetically defined murine cell populations. The GCN, which contained 91 distinct modules, was then used to gain three new biological insights. First, we found that the clustered protocadherin genes are differentially expressed during pancreas development. Pcdhγ genes are preferentially expressed in pancreatic endoderm, Pcdhß genes in nascent islets, and Pcdhα genes in mature ß-cells. Second, after extracting sub-networks of transcriptional regulators for each developmental stage, we identified 81 zinc finger protein (ZFP) genes that are preferentially expressed during endocrine specification and ß-cell maturation. Third, we used the GCN to select three ZFPs for further analysis by CRISPR mutagenesis of mice. Zfp800 null mice exhibited early postnatal lethality, and at E18.5 their pancreata exhibited a reduced number of pancreatic endocrine cells, alterations in exocrine cell morphology, and marked changes in expression of genes involved in protein translation, hormone secretion and developmental pathways in the pancreas. Together, our results suggest that developmentally oriented GCNs have utility for gaining new insights into gene regulation during organogenesis.

High-Performance Indoor Perovskite Solar Cells by Self-Suppression of Intrinsic Defects via a Facile Solvent-Engineering Strategy.

Lead halide perovskite solar cells have been emerging as very promising candidates for applications in indoor photovoltaics. To maximize their indoor performance, it is of critical importance to suppress intrinsic defects of the perovskite active layer. Herein, a facile solvent-engineering strategy is developed for effective suppression of both surface and bulk defects in lead halide perovskite indoor solar cells, leading to a high efficiency of 35.99% under the indoor illumination of 1000 lux Cool-white light-emitting diodes. Replacing dimethylformamide (DMF) with N-methyl-2-pyrrolidone (NMP) in the perovskite precursor solvent significantly passivates the intrinsic defects within the thus-prepared perovskite films, prolongs the charge carrier lifetimes and reduces non-radiative charge recombination of the devices. Compared to the DMF, the much higher interaction energy between NMP and formamidinium iodide/lead halide contributes to the markedly improved quality of the perovskite thin films with reduced interfacial halide deficiency and non-radiative charge recombination, which in turn enhances the device performance. This work paves the way for developing efficient indoor perovskite solar cells for the increasing demand for power supplies of Internet-of-Things devices.

Effect of nitro-conjugated linoleic acid on the inflammatory response of murine macrophages activated with lipopolysaccharide derived from Prevotella intermedia.

Nitro-conjugated linoleic acid (NO2-CLA) has been observed to manifest salutary signaling responses, including anti-inflammatory and antioxidant properties. Here, the authors have explored the influence and underlying mechanisms of NO2-CLA on the proinflammatory reaction of murine macrophages that were challenged with lipopolysaccharide (LPS) derived from Prevotella intermedia, a putative periodontopathic bacterium. Treatment of LPS-activated RAW264.7 cells with NO2-CLA notably dampened the secretion of iNOS-derived NO, IL-1ß and IL-6 as well as their gene expressions and significantly enhanced the markers for M2 macrophage polarization. NO2-CLA promoted the HO-1 expression in cells challenged with LPS, and tin protoporphyrin IX, an HO-1 inhibitor, significantly reversed the NO2-CLA-mediated attenuation of NO secretion, but not IL-1ß or IL-6. We found that cells treated with NO2-CLA significantly increased mRNA expression of PPAR-γ compared to control cells, and NO2-CLA significantly reverted the decrease in PPAR-γ mRNA caused by LPS. Nonetheless, antagonists to PPAR-γ were unable to reverse the NO2-CLA-mediated suppression of inflammatory mediators. In addition, NO2-CLA did not alter the p38 and JNK activation elicited by LPS. Both NF-κB reporter activity and IκB-α degradation caused by LPS were notably diminished by NO2-CLA. NO2-CLA was observed to interrupt the nuclear translocation and DNA binding of p50 subunits caused by LPS with no obvious alterations in p65 subunits. Further, NO2-CLA attenuated the phosphorylation of STAT1/3 elicited in response to LPS. We propose that NO2-CLA could be considered as a possible strategy for the therapy of periodontal disease, although additional researches are certainly required to confirm this.

Neonatal and maternal adverse outcomes and exposure to nonsteroidal anti-inflammatory drugs during early pregnancy in South Korea: A nationwide cohort study.

BACKGROUND: Existing data on the use of nonsteroidal anti-inflammatory drugs (NSAIDs) during late pregnancy is well established, providing assurance. However, the use of NSAIDs during early pregnancy remains inconclusive owing to conflicting findings on adverse neonatal outcomes as well as the limited data on adverse maternal outcomes. Therefore, we sought to investigate whether early prenatal exposure to NSAIDs was associated with neonatal and maternal adverse outcomes. METHODS AND FINDINGS: We conducted a nationwide, population-based cohort study using Korea's National Health Insurance Service (NHIS) database with a mother-offspring cohort constructed and validated by the NHIS to include all live births in women aged 18 to 44 years between 2010 and 2018. We defined exposure to NSAIDs as at least two records of NSAID prescriptions during early pregnancy (first 90 days of pregnancy for congenital malformations and first 19 weeks for nonmalformation outcomes) and compared against three distinct referent groups of (1) unexposed, no NSAID prescription during the 3 months before pregnancy start to end of early pregnancy; (2) acetaminophen-exposed, at least two acetaminophen prescriptions during early pregnancy (i.e., active comparator); and (3) past users, at least two NSAID prescriptions before the start of pregnancy but no relevant prescriptions during pregnancy. Outcomes of interest were adverse birth outcomes of major congenital malformations and low birth weight and adverse maternal outcomes of antepartum hemorrhage and oligohydramnios. We estimated relative risks (RRs) with 95% CIs using generalized linear models within a propensity score (PS) fine stratification weighted cohort that accounted for various potential confounders of maternal sociodemographic characteristics, comorbidities, co-medication use, and general markers of burden of illness. Of 1.8 million pregnancies in the PS weighted analyses, exposure to NSAIDs during early pregnancy was associated with slightly increased risks for neonatal outcomes of major congenital malformations (PS-adjusted RR, 1.14 [CI, 1.10 to 1.18]) and low birth weight (1.29 [1.25 to 1.33]), and for maternal outcome of oligohydramnios (1.09 [1.01 to 1.19]) but not antepartum hemorrhage (1.05 [0.99 to 1.12]). The risks of overall congenital malformations, low birth weight, and oligohydramnios remained significantly elevated despite comparing NSAIDs against acetaminophen or past users. Risks of adverse neonatal and maternal outcomes were higher with cyclooxygenase-2 selective inhibitors or use of NSAIDs for more than 10 days, whereas generally similar effects were observed across the three most frequently used individual NSAIDs. Point estimates were largely consistent across all sensitivity analyses, including the sibling-matched analysis. Main limitations of this study are residual confounding by indication and from unmeasured factors. CONCLUSIONS: This large-scale, nationwide cohort study found that exposure to NSAIDs during early pregnancy was associated with slightly higher risks of neonatal and maternal adverse outcomes. Clinicians should therefore carefully weigh the benefits of prescribing NSAIDs in early pregnancy against its modest, but possible, risk of neonatal and maternal outcomes, where if possible, consider prescribing nonselective NSAIDs for <10 days, along with continued careful monitoring for any safety signals.

Hepatocyte-specific loss of LAP2α protects against diet-induced hepatic steatosis, steatohepatitis, and fibrosis in male mice.

There is increasing evidence for the importance of the nuclear envelope in lipid metabolism, nonalcoholic fatty liver disease (NAFLD), and nonalcoholic steatohepatitis (NASH). Human mutations in LMNA, encoding A-type nuclear lamins, cause early-onset insulin resistance and NASH, while hepatocyte-specific deletion of Lmna predisposes to NASH with fibrosis in male mice. Given that variants in the gene encoding LAP2α, a nuclear protein that regulates lamin A/C, were previously identified in patients with NAFLD, we sought to determine the role of LAP2α in NAFLD using a mouse genetic model. Hepatocyte-specific Lap2α-knockout (Lap2α(ΔHep)) mice and littermate controls were fed normal chow or high-fat diet (HFD) for 8 wk or 6 mo. Unexpectedly, male Lap2α(ΔHep) mice showed no increase in hepatic steatosis or NASH compared with controls. Rather, Lap2α(ΔHep) mice demonstrated reduced hepatic steatosis, with decreased NASH and fibrosis after long-term HFD. Accordingly, pro-steatotic genes including Cidea, Mogat1, and Cd36 were downregulated in Lap2α(ΔHep) mice, along with concomitant decreases in expression of pro-inflammatory and pro-fibrotic genes. These data indicate that hepatocyte-specific Lap2α deletion protects against hepatic steatosis and NASH in mice and raise the possibility that LAP2α could become a potential therapeutic target in human NASH.NEW & NOTEWORTHY The nuclear envelope and lamina regulate lipid metabolism and susceptibility to nonalcoholic steatohepatitis (NASH), but the role of the nuclear lamin-binding protein LAP2α in NASH has not been explored. Our data demonstrate that hepatocyte-specific loss of LAP2α protects against diet-induced hepatic steatosis, NASH, and fibrosis in male mice, with downregulation of pro-steatotic, pro-inflammatory, and pro-fibrotic lamin-regulated genes. These findings suggest that targeting LAP2α could have future potential as a novel therapeutic avenue in NASH.

Dysplastic Stem Cell Plasticity Functions as a Driving Force for Neoplastic Transformation of Precancerous Gastric Mucosa.

BACKGROUND & AIMS: Dysplasia carries a high risk of cancer development; however, the cellular mechanisms for dysplasia evolution to cancer are obscure. We have previously identified 2 putative dysplastic stem cell (DSC) populations, CD44v6neg/CD133+/CD166+ (double positive [DP]) and CD44v6+/CD133+/CD166+ (triple positive [TP]), which may contribute to cellular heterogeneity of gastric dysplasia. Here, we investigated functional roles and cell plasticity of noncancerous Trop2+/CD133+/CD166+ DSCs initially developed in the transition from precancerous metaplasia to dysplasia in the stomach. METHODS: Dysplastic organoids established from active Kras-induced mouse stomachs were used for transcriptome analysis, in vitro differentiation, and in vivo tumorigenicity assessments of DSCs. Cell heterogeneity and genetic alterations during clonal evolution of DSCs were examined by next-generation sequencing. Tissue microarrays were used to identify DSCs in human dysplasia. We additionally evaluated the effect of casein kinase 1 alpha (CK1α) regulation on the DSC activities using both mouse and human dysplastic organoids. RESULTS: We identified a high similarity of molecular profiles between DP- and TP-DSCs, but more dynamic activities of DP-DSCs in differentiation and survival for maintaining dysplastic cell lineages through Wnt ligand-independent CK1α/ß-catenin signaling. Xenograft studies demonstrated that the DP-DSCs clonally evolve toward multiple types of gastric adenocarcinomas and promote cancer cell heterogeneity by acquiring additional genetic mutations and recruiting the tumor microenvironment. Last, growth and survival of both mouse and human dysplastic organoids were controlled by targeting CK1α. CONCLUSIONS: These findings indicate that the DSCs are de novo gastric cancer-initiating cells responsible for neoplastic transformation and a promising target for intervention in early induction of gastric cancer.

A Prospective Cohort Study of Novel Markers of Hepatitis B Virus Replication in Human Immunodeficiency Virus Coinfection.

BACKGROUND & AIMS: The contribution of the novel biomarkers, hepatitis B virus (HBV) RNA and HBV core-related antigen (HBcrAg), to characterization of HBV-human immunodeficiency virus (HIV) coinfection is unclear. We evaluated the longitudinal dynamics of HBV RNA and HBcrAg and their association with classical HBV serum biomarkers and liver histology and viral staining. METHODS: HBV-HIV co-infected adults from 8 North American centers entered a National Institutes of Health-funded prospective cohort study. Demographic, clinical, serological, and virological data were collected at entry and every 24 to 48 weeks for up to 192 weeks. Participants with HBV RNA and HBcrAg measured ≥2 times (N = 95) were evaluated; 56 had paired liver biopsies obtained at study entry and end of follow-up. RESULTS: Participants had a median age of 50 years; 97% were on combination anti-viral therapy. In hepatitis B e antigen (HBeAg)+ participants, there were significant declines in HBV RNA and HBcrAg over 192 weeks that tracked with declines in HBeAg, hepatitis B surface antigen, HBV DNA, and hepatitis B core antigen (HBcAg) hepatocyte staining grade (all P < .05). In HBeAg- participants, there were not significant declines in HBV RNA (P = .49) and HBcrAg (P = .63), despite modest reductions in hepatitis B surface antigen (P < .01) and HBV DNA (P = .03). HBV serum biomarkers were not significantly related to change in hepatic activity index, Ishak fibrosis score, or hepatocyte HBcAg loss (all P > .05). CONCLUSIONS: In HBV-HIV coinfected adults on suppressive dually active antiviral therapy, the use of novel HBV markers reveals continued improvement in suppression of HBV transcription and translation over time. The lack of further improvement in HBV serum biomarkers among HBeAg- patients suggests limits to the benefit of combination anti-viral therapy and provide rationale for additional agents with distinct mechanisms of action.

Immunostaining for hepatitis B viral antigens in liver: Association with clinical, biochemical, and virologic features of disease.

BACKGROUND AND AIM: Staining for hepatitis B viral antigens is often done in liver biopsies from patients with chronic hepatitis B, but its correlates with clinical phenotypes are not well described. METHODS: Biopsies were collected from a large cohort of adults and children with chronic hepatitis B viral infection through the Hepatitis B Research Network. Immunohistochemical staining of sections was done for hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) and then centrally read by the pathology committee. The degree of liver injury and pattern of staining were then correlated with clinical characteristics, including the clinical phenotype of hepatitis B. RESULTS: Biopsies from 467 subjects were studied, including 46 from children. Immunostaining for HBsAg was positive in 417 (90%) with scattered hepatocyte staining being the most common pattern. HBsAg staining correlated best with serum levels of HBsAg and hepatitis B viral DNA; the absence of HBsAg staining was often a prelude to loss of HBsAg from serum. HBcAg staining was positive in 225 (49%), and, while cytoplasmic staining was more frequent than nuclear staining, both nuclear and cytoplasmic positivity were often seen in the same specimen. Staining for HBcAg correlated with both level of viremia and liver injury. No biopsies from inactive carriers had stainable HBcAg, while 91% of the biopsies from those with hepatitis B e antigen-positive chronic hepatitis B stained positively for HBcAg. CONCLUSION: Immunostaining for hepatitis B viral antigens may yield helpful insights into liver disease pathogenesis but appears to add little to commonly used serological and biochemical blood tests.

Effect of telmisartan on an experimental model of periodontitis in mice.

OBJECTIVE: This study was performed to explore the impact of telmisartan on experimental periodontitis in mice, in terms of alveolar bone destruction, by using micro-computed tomography analysis. MATERIALS AND METHODS: Male BALB/c mice were divided into four groups of 7 to 9 mice each: control (C) group; experimental periodontitis (E) group; experimental periodontitis-plus-telmisartan 5 mg/kg (ET5) group; and experimental periodontitis-plus-telmisartan 10 mg/kg (ET10) group. The mice in Group C were not subjected to experimental periodontitis. The other mice from Groups E, ET5 and ET10 were exposed to periodontitis. Periodontitis was induced by inoculation with Porphyromonas gingivalis. RESULTS: Telmisartan significantly suppressed both the reduction in alveolar bone height and increase of root exposure caused by P. gingivalis infection. When mice were treated with telmisartan, the decrease in the bone volume fraction induced by the infection was notably recovered. In addition, telmisartan reversed P. gingivalis-induced alterations in the microstructural parameters of trabecular bone, except trabecular thickness.No significant difference was evident between Groups ET5 and ET10 in both the extent of alveolar bone loss and microstructural parameters assessed, except bone volume fraction and trabecular number. CONCLUSION: Telmisartan may have potential benefits as a host modulation agent for the therapy of periodontitis.

Carbon monoxide-releasing molecule-401, a water-soluble manganese-based metal carbonyl, suppresses Prevotella intermedia lipopolysaccharide-induced production of nitric oxide in murine macrophages.

CONTEXT: Many reports in the literature have suggested the therapeutic value of carbon monoxide-releasing molecules (CORMs) against various diseases. However, to date, little is known about their possible influence on periodontal disease. OBJECTIVE: This study was performed to investigate the influence of CORM-401 on the generation of nitric oxide (NO) in murine macrophage cells activated with lipopolysaccharide (LPS) derived from Prevotella intermedia, a pathogen associated with periodontal disease. MATERIALS AND METHODS: LPS was isolated by the hot phenol-water method. Culture supernatants were analyzed for NO. Real-time PCR and immunoblotting were conducted to quantify mRNA and protein expression, respectively. NF-κB-dependent SEAP levels were estimated by reporter assay. DNA-binding of NF-κB was also analyzed. RESULTS: CORM-401 caused an apparent suppression of NO production through inhibition of iNOS at both the mRNA and protein levels in RAW264.7 cells stimulated with P. intermedia LPS. CORM-401 upregulated the expression of both the HO-1 gene and its protein in LPS-activated cells, and treatment with the HO-1 inhibitor significantly reversed the attenuating influence of CORM-401 against LPS-induced generation of NO. CORM-401 caused an apparent attenuation of NF-κB-dependent SEAP release induced by LPS. IκB-α degradation and nuclear translocation of NF-κB p50 subunit induced by LPS were significantly reduced by CORM-401. Additionally, CORM-401 significantly attenuated DNA-binding of p65 and p50 induced by LPS. CORM-401 attenuated NO generation induced by P. intermedia LPS independently of PPAR-γ, JNK, p38 and STAT1/3. CONCLUSION: The modulation of host inflammatory response by CORM-401 might be of help in the therapy of periodontal disease.

A Transcriptome-Wide Analysis of Psoriasis: Identifying the Potential Causal Genes and Drug Candidates.

Psoriasis is a chronic inflammatory skin disease characterized by cutaneous eruptions and pruritus. Because the genetic backgrounds of psoriasis are only partially revealed, an integrative and rigorous study is necessary. We conducted a transcriptome-wide association study (TWAS) with the new Genotype-Tissue Expression version 8 reference panels, including some tissue and multi-tissue panels that were not used previously. We performed tissue-specific heritability analyses on genome-wide association study data to prioritize the tissue panels for TWAS analysis. TWAS and colocalization (COLOC) analyses were performed with eight tissues from the single-tissue panels and the multi-tissue panels of context-specific genetics (CONTENT) to increase tissue specificity and statistical power. From TWAS, we identified the significant associations of 101 genes in the single-tissue panels and 64 genes in the multi-tissue panels, of which 26 genes were replicated in the COLOC. Functional annotation and network analyses identified that the genes were associated with psoriasis and/or immune responses. We also suggested drug candidates that interact with jointly significant genes through a conditional and joint analysis. Together, our findings may contribute to revealing the underlying genetic mechanisms and provide new insights into treatments for psoriasis.

Piperine Induces Apoptosis and Autophagy in HSC-3 Human Oral Cancer Cells by Regulating PI3K Signaling Pathway.

Currently, therapies for treating oral cancer have various side effects; therefore, research on treatment methods employing natural substances is being conducted. This study aimed to investigate piperine-induced apoptosis and autophagy in HSC-3 human oral cancer cells and their effects on tumor growth in vivo. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay demonstrated that piperine reduced the viability of HSC-3 cells and 4',6-diamidino-2-phenylindole staining, annexin-V/propidium iodide staining, and analysis of apoptosis-related protein expression confirmed that piperine induces apoptosis in HSC-3 cells. Additionally, piperine-induced autophagy was confirmed by the observation of increased acidic vesicular organelles and autophagy marker proteins, demonstrating that autophagy in HSC-3 cells induces apoptosis. Mechanistically, piperine induced apoptosis and autophagy by inhibiting the phosphatidylinositol-3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin pathway in HSC-3 cells. We also confirmed that piperine inhibits oral cancer tumor growth in vivo via antitumor effects related to apoptosis and PI3K signaling pathway inhibition. Therefore, we suggest that piperine can be considered a natural anticancer agent for human oral cancer.

Chief cell plasticity is the origin of metaplasia following acute injury in the stomach mucosa.

OBJECTIVE: Metaplasia arises from differentiated cell types in response to injury and is considered a precursor in many cancers. Heterogeneous cell lineages are present in the reparative metaplastic mucosa with response to injury, including foveolar cells, proliferating cells and spasmolytic polypeptide-expressing metaplasia (SPEM) cells, a key metaplastic cell population. Zymogen-secreting chief cells are long-lived cells in the stomach mucosa and have been considered the origin of SPEM cells; however, a conflicting paradigm has proposed isthmal progenitor cells as an origin for SPEM. DESIGN: Gastric intrinsic factor (GIF) is a stomach tissue-specific gene and exhibits protein expression unique to mature mouse chief cells. We generated a novel chief cell-specific driver mouse allele, GIF-rtTA. GIF-GFP reporter mice were used to validate specificity of GIF-rtTA driver in chief cells. GIF-Cre-RnTnG mice were used to perform lineage tracing during homoeostasis and acute metaplasia development. L635 treatment was used to induce acute mucosal injury and coimmunofluorescence staining was performed for various gastric lineage markers. RESULTS: We demonstrated that mature chief cells, rather than isthmal progenitor cells, serve as the predominant origin of SPEM cells during the metaplastic process after acute mucosal injury. Furthermore, we observed long-term label-retaining chief cells at 1 year after the GFP labelling in chief cells. However, only a very small subset of the long-term label-retaining chief cells displayed the reprogramming ability in homoeostasis. In contrast, we identified chief cell-originating SPEM cells as contributing to lineages within foveolar cell hyperplasia in response to the acute mucosal injury. CONCLUSION: Our study provides pivotal evidence for cell plasticity and lineage contributions from differentiated gastric chief cells during acute metaplasia development.

Controllable Acceleration and Deceleration of Charge Carrier Transport in Metal-Halide Perovskite Single-Crystal by Cs-Cation Induced Bandgap Engineering.

Charge carrier transport in materials is of essential importance for photovoltaic and photonic applications. Here, the authors demonstrate a controllable acceleration or deceleration of charge carrier transport in specially structured metal-alloy perovskite (MACs)PbI3 (MA= CH3 NH3 ) single-crystals with a gradient composition of CsPbI3 /(MA1- x Csx )PbI3 /MAPbI3 . Depending on the Cs-cation distribution in the structure and therefore the energy band alignment, two different effects are demonstrated: i) significant acceleration of electron transport across the depth driven by the gradient band alignment and suppression of electron-hole recombination, benefiting for photovoltaic and detector applications; and ii) decelerated electron transport and thus improved radiative carrier recombination and emission efficiency, highly beneficial for light and display applications. At the same time, the top Cs-layer results in hole localization in the top layer and surface passivation. This controllable acceleration and deceleration of electron transport is critical for various applications in which efficient electron-hole separation and suppressed nonradiative electron-hole recombination is demanded.

CRISPR technologies for the treatment of Duchenne muscular dystrophy.

The emerging clustered regularly interspaced short palindromic repeats (CRISPR)-mediated genome editing technologies have progressed remarkably in recent years, opening up the potential of precise genome editing as a therapeutic approach to treat various diseases. The CRISPR-CRISPR-associated (Cas) system is an attractive platform for the treatment of Duchenne muscular dystrophy (DMD), which is a neuromuscular disease caused by mutations in the DMD gene. CRISPR-Cas can be used to permanently repair the mutated DMD gene, leading to the expression of the encoded protein, dystrophin, in systems ranging from cells derived from DMD patients to animal models of DMD. However, the development of more efficient therapeutic approaches and delivery methods remains a great challenge for DMD. Here, we review various therapeutic strategies that use CRISPR-Cas to correct or bypass DMD mutations and discuss their therapeutic potential, as well as obstacles that lie ahead.