Pharmacological effect of cepharanthine on SARS-CoV-2-induced disease in a Syrian hamster model.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains a global public health threat. Although several effective vaccines and therapeutics have been developed, continuous emergence of new variants necessitates development of drugs with different mechanisms of action. Recent studies indicate that cepharanthine, a chemical derivative purified from Stephania cepharantha, inhibits SARS-CoV-2 replication in vitro. METHODS: This study examined the in vivo effects of cepharanthine using a Syrian hamster SARS-CoV-2 infection model. To evaluate the prophylactic and therapeutic effects, cepharanthine was intranasally administered before or after SARS-CoV-2 infection. Effects were assessed by monitoring body weight changes, lung pathology, lung viral load, and inflammatory response in the lungs. RESULTS: Pre-infection administration of cepharanthine resulted in less weight loss, reduced virus titers, alleviated histopathological severity, and decreased lung inflammation. Furthermore, post-infection administration of cepharanthine also exhibited therapeutic effects. CONCLUSIONS: This study demonstrated that both prophylactic and therapeutic administration of cepharanthine reduces the pathogenesis of COVID-19 in a Syrian hamster SARS-CoV-2 infection model. Our findings suggest that cepharanthine is a potential therapeutic agent against COVID-19.

Tubular Endogenous Erythropoietin Protects Renal Function against Ischemic Reperfusion Injury.

Many large-scale studies show that exogenous erythropoietin, erythropoiesis-stimulating agents, lack any renoprotective effects. We investigated the effects of endogenous erythropoietin on renal function in kidney ischemic reperfusion injury (IRI) using the prolyl hydroxylase domain (PHD) inhibitor, Roxadustat (ROX). Four h of hypoxia (7% O2) and 4 h treatment by ROX prior to IRI did not improve renal function. In contrast, 24-72 h pretreatment by ROX significantly improved the decline of renal function caused by IRI. Hypoxia and 4 h ROX increased interstitial cells-derived Epo production by 75- and 6-fold, respectively, before IRI, and worked similarly to exogenous Epo. ROX treatment for 24-72 h increased Epo production during IRI by 9-fold. Immunohistochemistry revealed that 24 h ROX treatment induced Epo production in proximal and distal tubules and worked similarly to endogenous Epo. Our data show that tubular endogenous Epo production induced by 24-72 h ROX treatment results in renoprotection but peritubular exogenous Epo production by interstitial cells induced by hypoxia and 4 h ROX treatment did not. Stimulation of tubular, but not peritubular, Epo production may link to renoprotection.

Prophylactic administration of ivermectin attenuates SARS-CoV-2 induced disease in a Syrian Hamster Model.

COVID-19, caused by SARS-CoV-2 infection, is currently among the most important public health concerns worldwide. Although several effective vaccines have been developed, there is an urgent clinical need for effective pharmaceutical treatments for treatment of COVID-19. Ivermectin, a chemical derivative of avermectin produced by Streptomyces avermitilis, is a macrocyclic lactone with antiparasitic activity. Recent studies have shown that ivermectin inhibits SARS-CoV-2 replication in vitro. In the present study, we investigated the in vivo effects of ivermectin in a hamster model of SARS-CoV-2 infection. The results of the present study demonstrate oral administration of ivermectin prior to SARS-CoV-2 infection in hamsters was associated with decreased weight loss and pulmonary inflammation. In addition, the administration of ivermectin reduced pulmonary viral titers and mRNA expression level of pro-inflammatory cytokines associated with severe COVID-19 disease. The administration of ivermectin rapidly induced the production of virus-specific neutralizing antibodies in the late stage of viral infection. Zinc concentrations leading to immune quiescence were also significantly higher in the lungs of ivermectin-treated hamsters compared to controls. These results indicate that ivermectin may have efficacy in reducing the development and severity of COVID-19 by affecting host immunity in a hamster model of SARS-CoV-2 infection.

Targeted DNA Methylation in Mouse Early Embryos.

In germ cell lines, including early preimplantation embryos, centromeres and pericentromeres are known to show a marked hypomethylation pattern compared to somatic cells. Elucidation of the biological function of this region-specific DNA hypomethylation state, region-specific epigenomic manipulation is essential as an analytical method. We have applied genome editing to show that region-specific DNA methylation can be effectively introduced by a fusion protein, TALE, which recognizes pericentromeres, and SssI, a bacterial CpG methyltransferase. This makes it possible to increase the DNA methylation state of the pericentromeres, which is normally about 20%, to about 60-75%, enabling comparative analysis of the developmental processes of normal embryos with hypomethylated pericentromeres and embryos that have been epigenetically edited to be hypermethylated. In this chapter, we describe a method for introducing DNA methylation into pericentromeres of early mouse embryos by expressing TALE-SssI fusion protein and a method for detecting DNA methylation.

Immune profile analysis of peripheral blood and tumors of lung cancer patients treated with immune checkpoint inhibitors.

Background: Immune checkpoint inhibitors (ICIs) have become central to lung cancer drug therapy, and establishing biomarkers that can predict effects and adverse events (AEs) is awaited. We prospectively analyzed the association between the immune-related molecular expression in peripheral blood mononuclear cells (PBMCs) and lung cancer tissues, and the effects of ICI monotherapy. Methods: Twenty-one patients with advanced non-small cell lung cancer (NSCLC) who received ICI monotherapy were included. Changes in the expression of immune-related molecules in PBMCs before and after the administration of ICI were analyzed by flow cytometry. The major histocompatibility complex (MHC) class I and programmed cell death-ligand 1 (PD-L1) expression of cancer cells, and the PD-L1, CD8 and CD103 expression of tumor infiltrating immune cells in lung cancer tissue before the administration of ICI were confirmed by immunohistochemistry (IHC). Results: Twenty-one patients were investigated, including 11 adenocarcinoma and 10 squamous cell carcinoma cases. Anti-programmed cell death protein-1 (PD-1) antibody (n=18) and anti-PD-L1 antibody (n=3) were administered. The clinical responses were graded as follows: complete response (CR) (n=1), partial response (PR) (n=7), stable disease (SD) (n=10) and progressive disease (PD) (n=3). Among immune-related molecules expressed in PBMCs, the CD103+ CD39+ CD8+ T cell change after administration closely correlated with the clinical response. In the univariate analyses of the factors associated with progression-free survival (PFS), CD103+ CD39+ CD8+ cell change after administration was identified as a significant prognostic factor, while the CD103+ CD39+ CD8+ cell change after administration and Brinkman index were independent prognostic factors in a multivariate analysis of the factors associated with PFS. Conclusions: The CD103+ CD39+ CD8+ cell change after administration may predict the efficacy of ICIs.

Detection of Kita-Kyushu Lung Cancer Antigen-1, a Cancer/Testis Antigen, in the Stomach Close to a Cancerous Condition.

Background: Kita-Kyushu lung cancer antigen-1 (KK-LC-1), encoded by CT83, is a cancer/testis antigen (CTA) and an attractive target for immunotherapy. Our previous study demonstrated frequent CT83 expression in gastric cancers (GCs) and non-tumor sites of the stomach with tumors. Additionally, there was a correlation with Helicobacter pylori (Hp) infection. Since it currently remains unclear whether KK-LC-1 is expressed in the stomach without GC, this study investigated KK-LC-1 expression in non-GC stomach. Methods: We investigated differences in CT83 gene expression at non-tumor sites of stomachs with or without tumors in 118 GC patients and 115 non-GC patients. Fisher's exact test was used for statistical analyses. Results: CT83 expression was detected in 77% of non-tumor sites in stomachs with tumors, which was significantly higher than in stomachs without tumors (7%, p < 0.0001). All patients with CT83 expression at non-tumor sites of their stomachs without tumors carried Hp. Conclusion: CT83 appears to be rarely expressed in the atrophic stomach, and furthermore, a part of patients positive for its expression will develop GC in the future, suggesting that CT83 expression is a useful marker for predicting GC.

Effects of Roxadustat on Erythropoietin Production in the Rat Body.

Anemia is a major complication of chronic renal failure. To treat this anemia, prolylhydroxylase domain enzyme (PHD) inhibitors as well as erythropoiesis-stimulating agents (ESAs) have been used. Although PHD inhibitors rapidly stimulate erythropoietin (Epo) production, the precise sites of Epo production following the administration of these drugs have not been identified. We developed a novel method for the detection of the Epo protein that employs deglycosylation-coupled Western blotting. With protein deglycosylation, tissue Epo contents can be quantified over an extremely wide range. Using this method, we examined the effects of the PHD inhibitor, Roxadustat (ROX), and severe hypoxia on Epo production in various tissues in rats. We observed that ROX increased Epo mRNA expression in both the kidneys and liver. However, Epo protein was detected in the kidneys but not in the liver. Epo protein was also detected in the salivary glands, spleen, epididymis and ovaries. However, both PHD inhibitors (ROX) and severe hypoxia increased the Epo protein abundance only in the kidneys. These data show that, while Epo is produced in many tissues, PHD inhibitors as well as severe hypoxia regulate Epo production only in the kidneys.

Effects of Angiotensin II on Erythropoietin Production in the Kidney and Liver.

The kidney is a main site of erythropoietin production in the body. We developed a new method for the detection of Epo protein by deglycosylation-coupled Western blotting. Detection of deglycosylated Epo enables the examination of small changes in Epo production. Using this method, we investigated the effects of angiotensin II (ATII) on Epo production in the kidney. ATII stimulated the plasma Epo concentration; Epo, HIF2α, and PHD2 mRNA expression in nephron segments in the renal cortex and outer medulla; and Epo protein expression in the renal cortex. In situ hybridization and immunohistochemistry revealed that ATII stimulates Epo mRNA and protein expression not only in proximal tubules but also in collecting ducts, especially in intercalated cells. These data support the regulation of Epo production in the kidney by the renin-angiotensin-aldosterone system (RAS).

Erratum: Yamazaki et al. Editing DNA Methylation in Mammalian Embryos. Int. J. Mol. Sci. 2020, 21, 637.

The authors wish to make the following corrections to our previously published paper [...].

Mint3 depletion-mediated glycolytic and oxidative alterations promote pyroptosis and prevent the spread of Listeria monocytogenes infection in macrophages.

Listeria monocytogenes (LM) infection induces pyroptosis, a form of regulated necrosis, in host macrophages via inflammasome activation. Here, we examined the role of Mint3 in macrophages, which promotes glycolysis via hypoxia-inducible factor-1 activation, during the initiation of pyroptosis following LM infection. Our results showed that Mint3-deficient mice were more resistant to lethal listeriosis than wild-type (WT) mice. Additionally, the mutant mice showed higher levels of IL-1ß/IL-18 in the peritoneal fluid during LM infection than WT mice. Moreover, ablation of Mint3 markedly increased the activation of caspase-1, maturation of gasdermin D, and pyroptosis in macrophages infected with LM in vitro, suggesting that Mint3 depletion promotes pyroptosis. Further analyses revealed that Mint3 depletion upregulates inflammasome assembly preceding pyroptosis via glycolysis reduction and reactive oxygen species production. Pharmacological inhibition of glycolysis conferred resistance to listeriosis in a Mint3-dependent manner. Moreover, Mint3-deficient mice treated with the caspase-1 inhibitor VX-765 were as susceptible to LM infection as WT mice. Taken together, these results suggest that Mint3 depletion promotes pyroptosis in host macrophages, thereby preventing the spread of LM infection. Mint3 may serve as a target for treating severe listeriosis by inducing pyroptosis in LM-infected macrophages.

Differentiation of endogenous erythropoietin and exogenous ESAs by Western blotting.

Doping tests for the illegal use of erythropoiesis-stimulating agents (ESAs) have been developed. We developed a new Western blotting method to detect and distinguish endogenous erythropoietin (Epo, 35-38 kDa) and exogenous ESAs (epoetin α and ß, 38-42 kDa; darbepoetin α, 47-50 kDa; epoetin ß pegol, 93-110 kDa). Epo and ESAs are glycoproteins and deglycosylation using peptide-N-glycosidase F shifted all Epo and ESA bands except epoetin ß pegol to 22 kDa. We cut the bands of Epo and ESAs from SDS-PAGE gels and analyzed them by Liquid Chromatography/Mass Spectrometry (LC/MS). LC/MS detected all endogenous Epo and exogenous ESAs as deglycosylated 22 kDa Epo, indicating that LC/MS analysis could confirm the presence of Epo or ESA, but could not distinguish between endogenous Epo and exogenous ESAs. We propose the following Epo doping tests: 1) detect Epo or ESAs by Western blotting of the glycosylated form; 2) increase the reliability by the band shift following deglycosylation; and 3) complete confirmation of Epo or ESA by LC/MS analysis using cut gels. One of the advantages of our method is that pre-purification of samples for Epo is not required in our Western blotting.

Erythropoietin production by the kidney and the liver in response to severe hypoxia evaluated by Western blotting with deglycosylation.

The detection of erythropoietin (Epo) protein by Western blotting has required pre-purification of the sample. We developed a new Western blot method to detect plasma and urinary Epo using deglycosylation. Epo in urine and tissue, and erythropoiesis-stimulating agents (ESAs) in urine were directly detected by our Western blotting. Plasma Epo and ESAs were not detected by direct application but were detected by our Western blotting after deglycosylation. The broad bands of Epo and ESAs were shifted to 22 kDa by deglycosylation except for PEG-bound epoetin ß pegol. The 22 kDa band from an anemic patient's urine was confirmed by Liquid Chromatography/Mass Spectrometry (LC/MS) to contain human Epo. Severe hypoxia (7% O2, 4 hr) caused a 400-fold increase in deglycosylated Epo expression in rat kidneys, which is consistent with the increases in both Epo gene expression and plasma Epo concentration. Immunohistochemistry showed Epo expression in nephrons but not in interstitial cells under control conditions, and hypoxia increased Epo expression in interstitial cells but not in tubules. These data show that intrinsic Epo and all ESAs can be detected by Western blot either directly in urine or after deglycosylation in blood, and that the kidney but not the liver is the main site of Epo production in control and severe hypoxia. Our method will make the tests for Epo doping and detection easy.

Cancer/testis antigen, Kita-Kyushu lung cancer antigen-1 and ABCD stratification for diagnosing gastric cancers.

BACKGROUND: The ABCD stratification [(combination of serum pepsinogen (PG) levels and titers of antibody (immunoglobulin G, IgG) against Helicobacter pylori (H. pylori)] is effective for the classification of individuals at risk of developing gastric cancer (GC). The Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a Cancer/Testis antigen frequently expressed in GC. AIM: To evaluate the effectiveness of KK-LC-1 and ABCD stratification in the diagnosis of GC. METHODS: We analyzed the gene expression of KK-LC-1 in surgical specimens obtained from GC tumors. The levels of serum PG I/PG II and IgG against H. pylori were measured. According to their serological status, the patients were classified into the four groups of the ABCD stratification. RESULTS: Of the 77 examined patients, 63 (81.8%) expressed KK-LC-1. The IgG titers of H. pylori and PG II were significantly higher in patients expressing KK-LC-1 than those measured in patients not expressing KK-LC-1 (P = 0.0289 and P = 0.0041, respectively). The expression of KK-LC-1 in group C [PG method (+)/H. pylori infection (+)] was as high as 93.9% high. KK-LC-1 was also detected in group A [-/-]. CONCLUSION: The KK-LC-1 expression in GC was associated with H. pylori infection and atrophic status, so that, KK-LC-1 may be a useful marker for the diagnosis of GC.

Editing DNA Methylation in Mammalian Embryos.

DNA methylation in mammals is essential for numerous biological functions, such as ensuring chromosomal stability, genomic imprinting, and X-chromosome inactivation through transcriptional regulation. Gene knockout of DNA methyltransferases and demethylation enzymes has made significant contributions to analyzing the functions of DNA methylation in development. By applying epigenome editing, it is now possible to manipulate DNA methylation in specific genomic regions and to understand the functions of these modifications. In this review, we first describe recent DNA methylation editing technology. We then focused on changes in DNA methylation status during mammalian gametogenesis and preimplantation development, and have discussed the implications of applying this technology to early embryos.

Expression of Kita-Kyushu Lung Cancer Antigen-1 as Detected by a Novel Monoclonal Antibody in Gastric Cancer.

BACKGROUND/AIM: Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a known cancer/testis antigen. Our group has previously shown KK-LC-1 gene expression in gastric cancer. However, could not be detected the KK-LC-1 protein due to the lack of an appropriate antibody. Here, we assessed our original monoclonal antibody (Kmab34B3) and, using it, assessed the expression of KK-LC-1 in gastric cancer. PATIENTS AND METHODS: We evaluated an original monoclonal antibody against KK-LC-1 (Kmab34B3), and used this antibody to compare KK-LC-1 protein expression in tumour and non-tumour stomach cells from gastric cancer patients. RESULTS: Kmab34B3 stained testicular germ cells, and tumour cells in nine out of 11 (82%) specimens. In non-tumorous areas, Kmab34B3 stained 13 out of 29 (45%) pyloric gland specimens. Furthermore, Kmab34B3 also stained intestinal metaplasia positive and negative areas. CONCLUSION: Kmab34B3 was able to detect KK-LC-1 protein within tumour cells and the pyloric gland where the gene has been shown to be expressed. Therefore, it might be an attractive tool for detecting KK-LC-1 expression in precancerous and cancerous stomach cells.

Characterization of IL-17-producing T helper cells-like autoreactive T cells in aged mice.

IL-17-producing T helper cells (Th17) are attracting attention as a new CD4-positive subset of T cells, reported to be responsible for various autoimmune diseases through stimulation of the release of inflammatory cytokines from target cells. However, most investigations of Th17 mediation of autoimmune diseases have focused on the experimental autoimmune models derived from young animals, with few studies that have analyzed physiological factors such as aging. The present study analyzed autoreactive T cells established in a syngeneic mixed lymphocyte culture (sMLC) from aged mice and examined their similarity with Th17. IL-17-producing autoreactive CD4-intermediate T cells were observed in the sMLC; these expressed several stem cell markers or an immunosuppressive receptor PD-1 on the cell surface and so seemed to be different to typical Th17 cells. RT-PCR analysis revealed that purified Th17-like cells also expressed Il17a, Il17f, Il23r, Rorc and Tdt mRNA, but not Rag1 or Rag2 mRNA. These findings that it is likely that Th17-like cells are involved in autoimmune responses in aged mice.

Detection of KK-LC-1 Protein, a Cancer/Testis Antigen, in Patients with Breast Cancer.

BACKGROUND: Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen and predominant target for cancer immunotherapy. Its detection is only established based on gene expression. In this study, we established a monoclonal antibody against KK-LC-1 to detect its protein expression in formalin-fixed samples. MATERIALS AND METHODS: The monoclonal antibody against KK-LC-1 was evaluated and the detection of KK-LC-1 between gene expression and protein expression was compared in patients with breast cancer. The monoclonal antibody clone 34B3, which we established, stained testicular germ cells positively. RESULTS: The rates of detection of KK-LC-1 gene and protein expression were 11.8% and 52.9%, respectively. Protein expression was detected in all triple-negative breast cancer cases studied (n=8). Furthermore, KK-LC-1 was detected in all tumours without oestrogen receptor expression. CONCLUSION: This study indicated that KK-LC-1 expression was detected in breast cancer, especially in oestrogen receptor-negative subtypes.

Fludrocortisone stimulates erythropoietin production in the intercalated cells of the collecting ducts.

Erythropoietin has been thought to be secreted to plasma soon after the production because of the difficulty of Western blot analysis and immunohistochemistry. We established the new methods of Western blot analysis and immunohistochemistry. Using the new methods, we investigated the effects of aldosterone and fludrocortisone, an analogue of aldosterone on erythropoietin mRNA and protein production by the kidneys. Aldosterone stimulated Epo and HIF2α mRNA expressions in tubule suspensions and microdissected medullary thick ascending limbs and outer medullary collecting ducts. Western blot analysis showed a recombinant erythropoietin at 34-45 kDa and kidney erythropoietin at 36-40 and 42 kDa, both of which shifted to 22 kDa by deglycosylation. Erythropoietin protein expression was observed in the nephrons but not in the interstitial cells in control condition. Fludrocortisone stimulated erythropoietin mRNA and protein expressions in the distal nephrons, particularly in the intercalated cells of the collecting ducts. These data show that erythropoietin is produced by the nephrons by the regulation of renin-angiotensin-aldosterone system and not by the renal interstitial cells in control condition.

A superelderly case of TAFRO syndrome treated effectively using corticosteroid hormones.

Peripheral lymphocyte subsets may be less time-consuming and are a prognostic tool for managing thrombocytopenia, anasarca, myelofibrosis, renal dysfunction, and organomegaly (TAFRO) syndrome. Here, we report a superelderly case of plasma cell type TAFRO syndrome treated effectively using corticosteroid hormones.