Bacteroides uniformis Ameliorates Carbohydrate and Lipid Metabolism Disorders in Diabetic Mice by Regulating Bile Acid Metabolism via the Gut-Liver Axis.

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a metabolic syndrome characterized by chronic inflammation, insulin resistance, and islet cell damage. The prevention of T2DM and its associated complications is an urgent public health issue that affects hundreds of millions of people globally. Numerous studies suggest that disturbances in gut metabolites are important driving forces for the pathogenesis of diabetes. However, the functions and mechanisms of action of most commensal bacteria in T2DM remain largely unknown. METHODS: The quantification of bile acids (BAs) in fecal samples was performed using ultra-performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). The anti-diabetic effects of Bacteroides uniformis (B. uniformis) and its metabolites cholic acid (CA) and chenodeoxycholic acid (CDCA) were assessed in T2DM mice induced by streptozocin (STZ) plus high-fat diet (HFD). RESULTS: We found that the abundance of B. uniformis in the feces and the contents of CA and CDCA were significantly downregulated in T2DM mice. B. uniformis was diminished in diabetic individuals and this bacterium was sufficient to promote the production of BAs. Colonization of B. uniformis and intragastric gavage of CA and CDCA effectively improved the disorder of glucose and lipid metabolism in T2DM mice by inhibiting gluconeogenesis and lipolysis in the liver. CA and CDCA improved hepatic glucose and lipid metabolism by acting on the Takeda G protein-coupled receptor 5 (TGR5)/adenosine monophosphate-activated protein kinase (AMPK) signaling pathway since knockdown of TGR5 minimized the benefit of CA and CDCA. Furthermore, we screened a natural product-vaccarin (VAC)-that exhibited anti-diabetic effects by promoting the growth of B. uniformis in vitro and in vivo. Gut microbiota pre-depletion abolished the favorable effects of VAC in diabetic mice. CONCLUSIONS: These data suggest that supplementation of B. uniformis may be a promising avenue to ameliorate T2DM by linking the gut and liver.

Autopsy analysis reveals increased macrophage infiltration and cell apoptosis in COVID-19 patients with severe pulmonary fibrosis.

Clinical data indicates that SARS-CoV-2 infection-induced respiratory failure is a fatal condition for severe COVID-19 patients. However, the pathological alterations of different types of respiratory failure remained unknown for severe COVID-19 patients. This study aims to evaluate whether there are differences in the performance of various types of respiratory failure in severe COVID-19 patients and investigate the pathological basis for these differences. The lung tissue sections of severe COVID-19 patients were assessed for the degree of injury and immune responses. Transcriptome data were used to analyze the molecular basis in severe COVID-19 patients. Severe COVID-19 patients with combined oxygenation and ventilatory failure presented more severe pulmonary fibrosis, airway obstruction, and prolonged disease course. The number of M2 macrophages increased with the degree of fibrosis in patients, suggesting that it may be closely related to the development of pulmonary fibrosis. The co-existence of pro-inflammatory and anti-inflammatory cytokines in the pulmonary environment could also participate in the progression of pulmonary fibrosis. Furthermore, the increased apoptosis in the lungs of COVID-19 patients with severe pulmonary fibrosis may represent a critical factor linking sustained inflammatory responses to fibrosis. Our findings indicate that during the extended phase of COVID-19, antifibrotic and antiapoptotic treatments should be considered in conjunction with the progression of the disease.

Contrast-enhanced US to Improve Diagnostic Performance of O-RADS US Risk Stratification System for Malignancy.

Background The Ovarian-Adnexal Reporting and Data System (O-RADS) has limited specificity for malignancy. Contrast-enhanced US can help distinguish malignant from benign lesions, but its added value to O-RADS has not yet been assessed. Purpose To establish a diagnostic model combining O-RADS and contrast-enhanced US and to validate whether O-RADS plus contrast-enhanced US has a better diagnostic performance than O-RADS alone. Materials and Methods This prospective study included participants from May 2018 to March 2021 who underwent contrast-enhanced US before surgery and had lesions categorized as O-RADS 3, 4, or 5 by US, with a histopathologic reference standard. From April 2021 to July 2022, participants with pathologically confirmed ovarian-adnexal lesions were recruited for the validation group. In the pilot group, the initial enhancement time and enhancement intensity in comparison with the uterine myometrium, contrast agent distribution pattern, and dynamic changes in enhancement of lesions were assessed. Contrast-enhanced US features were used to calculate contrast-enhanced US scores for benign (score ≤2) and malignant (score ≥4) lesions. Lesions were then re-rated according to O-RADS category plus contrast-enhanced US scores. Receiver operating characteristic curves were constructed and compared using the DeLong method. The combined system was validated in an independent group. Results The pilot group included 76 women (mean age, 44 years ± 13 [SD]), and the validation group included 46 women (mean age, 42 years ± 14). Differences in initial enhancement time (P < .001), enhancement intensity (P < .001), and dynamic changes in enhancement (P < .001) between benign and malignant lesions were observed in the pilot group. Contrast-enhanced US scores were calculated using these features. The O-RADS risk stratification was upgraded one level for contrast-enhanced US scores of 4 or more and downgraded one level for contrast-enhanced US scores of 2 or less. In the validation group, the diagnostic performance of O-RADS plus contrast-enhanced US score was higher (area under the receiver operating characteristic curve [AUC] = 0.93) than O-RADS (AUC = 0.71, P < .001). Conclusion Contrast-enhanced US improved the diagnostic performance for malignancy of the O-RADS categories 3-5. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Grant in this issue.

Low level of ARID1A contributes to adaptive immune resistance and sensitizes triple-negative breast cancer to immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICIs) shed new light on triple-negative breast cancer (TNBC), but only a minority of patients demonstrate response. Therefore, adaptive immune resistance (AIR) needs to be further defined to guide the development of ICI regimens. METHODS: Databases, including The Cancer Genome Atlas, Gene Ontology Resource, University of California Santa Cruz Genome Browser, and Pubmed, were used to screen epigenetic modulators, regulators for CD8+ T cells, and transcriptional regulators of programmed cell death-ligand 1 (PD-L1). Human peripheral blood mononuclear cell (Hu-PBMC) reconstruction mice were adopted for xenograft transplantation. Tumor specimens from a TNBC cohort and the clinical trial CTR20191353 were retrospectively analyzed. RNA-sequencing, Western blotting, qPCR and immunohistochemistry were used to assess gene expression. Coculture assays were performed to evaluate the regulation of TNBC cells on T cells. Chromatin immunoprecipitation and transposase-accessible chromatin sequencing were used to determine chromatin-binding and accessibility. RESULTS: The epigenetic modulator AT-rich interaction domain 1A (ARID1A) gene demonstrated the highest expression association with AIR relative to other epigenetic modulators in TNBC patients. Low ARID1A expression in TNBC, causing an immunosuppressive microenvironment, promoted AIR and inhibited CD8+ T cell infiltration and activity through upregulating PD-L1. However, ARID1A did not directly regulate PD-L1 expression. We found that ARID1A directly bound the promoter of nucleophosmin 1 (NPM1) and that low ARID1A expression increased NPM1 chromatin accessibility as well as gene expression, further activating PD-L1 transcription. In Hu-PBMC mice, atezolizumab demonstrated the potential to reverse ARID1A deficiency-induced AIR in TNBC by reducing tumor malignancy and activating anti-tumor immunity. In CTR20191353, ARID1A-low patients derived more benefit from pucotenlimab compared to ARID1A-high patients. CONCLUSIONS: In AIR epigenetics, low ARID1A expression in TNBC contributed to AIR via the ARID1A/NPM1/PD-L1 axis, leading to poor outcome but sensitivity to ICI treatment.

A rare case of histiocytic proliferative disease in a cat.

A 7-year-old intact female domestic medium hair cat was examined at a veterinary clinic for a scabbed nodule over the right shoulder. Multiple nodules recurred at the same site after the first surgical excision, and a second surgical excision was performed. Histopathology demonstrated high-mitotic-rate neoplastic cells and therefore a histiocytic proliferative disease was initially suspected. The condition progressed rapidly within a 5-month period and the cat was euthanized due to sudden onset of severe dyspnea. Necropsy showed diffuse metastatic nodules in the lungs, confirming a histiocytic proliferative disease, with histiocytic sarcoma being the most likely differential diagnosis.

Un cas rare de maladie histiocytaire proliférative chez un chat. Une chatte domestique á poil moyen intacte de 7 ans a été examinée dans une clinique vétérinaire pour un nodule croûteux sur l'épaule droite. Plusieurs nodules sont réapparus au même site après la première excision chirurgicale, et une deuxième excision chirurgicale a été réalisée. L'histopathologie a mis en évidence des cellules néoplasiques á taux mitotique élevé et, par conséquent, une maladie proliférative histiocytaire a été initialement suspectée. L'état a progressé rapidement en l'espace de 5 mois et le chat a été euthanasié en raison de l'apparition soudaine d'une dyspnée sévère. L'autopsie a montré des nodules métastatiques diffus dans les poumons, confirmant une maladie proliférative histiocytaire, le sarcome histiocytaire étant le diagnostic différentiel le plus probable.(Traduit par Dr Serge Messier).

IDO-1 inhibitor INCB24360 elicits distant metastasis of basal extruded cancer cells in pancreatic ductal adenocarcinoma.

Neoplastic cells of non-immunogenic pancreatic ductal adenocarcinoma (PDAC) express indoleamine 2,3-dioxygenase 1 (IDO-1), an immunosuppressive enzyme. The metabolites of IDO-1 in cancers provide one-carbon units that annihilate effector T cells, and recruit immunosuppressive cells. In this study we investigated how IDO-1 affected the neoplastic cell behaviors in PDACs. Using multiple markers co-labeling method in 45-µm-thick tissue sections, we showed that IDO-1 expression was uniquely increased in the neoplastic cells extruded from ducts' apical or basal domain, but decreased in lymph metastatic cells. IDO-1+ extruding neoplastic cells displayed increased vimentin expression and decreased cytokeratin expression in PDACs, characteristics of epithelial-mesenchymal transition (EMT). However, IDO-1 expression was uncorrelated with immunosuppressive infiltrates and clinicopathological characteristics of grim outcome. We replicated basal extrusion with EMT in murine KPIC PDAC organoids by long-term IFN-γ induction; application of IDO-1 inhibitor INCB24360 or 1-MT partially reversed basal extrusion coupled EMT. Ido-1 deletion in KPIC cells deprived its tumorigenicity in immunocompetent mice, decreased cellular proliferation and macropinocytic ability, and increased immunogenicity. KPIC organoids with IFN-γ-induced basal extrusion did not accelerate distant metastasis, whereas inhibition IFN-γ-induced IDO-1 with INB24360 but not 1-MT in KPIC organoids elicited liver metastasis of subcutaneous KPIC organoid tumors, suggesting that lower IDO-1 activity accelerated distant metastasis, whereas IDO-1 was indispensable for tumorigenicity of PDAC cells and supports the survival of extruding cells.

Squamous-columnar junction of Von Ebner's glands may be a significant origin of squamous cell carcinomas in the base of the tongue.

Objectives: The histological origin of base of the tongue (BOT) carcinomas is still elusive, and most studies have been focusing on the lingual tonsil. In this study, we sought to identify the existence of the squamous-columnar junction (SCJ) in the human Von Ebner's glandular duct and explored the potential of that in forming squamous cell carcinomas in BOT. Materials and methods: The specific genomes of BOT carcinoma were acquired and screened out by The Cancer Genome Atlas (TCGA) database analysis. The 4-nitroquinoline-1-oxide (4-NQO)-treated mouse model was used to explore the transformation of SCJ during cancerization. We used immunohistochemistry to confirm the characteristics of SCJ in human Von Ebner's gland, which were further compared with those in the anus and cervix. Results: The SCJ in the human Von Ebner's glandular duct was found to be similar to that of the cervix and anus. The transformation zone in the 4-NQO-treated mouse model had a multilayered epithelium structure similar to that of HPV16-transgenic mice. In human, the transformation zone of Von Ebner's gland is also similar to that of the cervix and anus. Conclusion: It is the first time that the existence of SCJ in the opening of the human Von Ebner's glandular duct was confirmed. The SCJ of Von Ebner's glands may be a significant origin of squamous cell carcinomas in BOT.

Identification of a TGF-ß signaling-related gene signature for prediction of immunotherapy and targeted therapy for lung adenocarcinoma.

BACKGROUND: Transforming growth factor (TGF)-ß signaling functions importantly in regulating tumor microenvironment (TME). This study developed a prognostic gene signature based on TGF-ß signaling-related genes for predicting clinical outcome of patients with lung adenocarcinoma (LUAD). METHODS: TGF-ß signaling-related genes came from The Molecular Signature Database (MSigDB). LUAD prognosis-related genes were screened from all the genes involved in TGF-ß signaling using least absolute shrinkage and selection operator (LASSO) Cox regression analysis and then used to establish a risk score model for LUAD. ESTIMATE and CIBERSORT analyzed infiltration of immune cells in TME. Immunotherapy response was analyzed by the TIDE algorithm. RESULTS: A LUAD prognostic 5-gene signature was developed based on 54 TGF-ß signaling-related genes. Prognosis of high-risk patients was significantly worse than low-risk patients. Both internal validation and external dataset validation confirmed a high precision of the risk model in predicting the clinical outcomes of LUAD patients. Multivariate Cox analysis demonstrated the model independence in OS prediction of LUAD. The risk model was significantly related to the infiltration of 9 kinds of immune cells, matrix, and immune components in TME. Low-risk patients tended to respond more actively to anti-PD-1 treatment, while high-risk patients were more sensitive to chemotherapy and targeted therapy. CONCLUSIONS: The 5-gene signature based on TGF-ß signaling-related genes showed potential for LUAD management.

Electroacupuncture Attenuated Phenotype Transformation of Vascular Smooth Muscle Cells via PI3K/Akt and MAPK Signaling Pathways in Spontaneous Hypertensive Rats.

OBJECTIVE: To investigate whether the antihypertensive mechanism of electroacupuncture (EA) is associated with attenuating phenotype transformation of vascular smooth muscle cells (VSMCs) via phosphoinositide3-kinase (PI3K)/protein kinase B (Akt) and mitogen-activated protein kinase (MAPK) signaling pathways. METHODS: Eight Wistar-ktoyo (WKY) rats were set as normal blood pressure group (normal group). A total of 32 spontaneous hypertensive rats (SHRs) were randomly divided into 4 groups using random number tables: a model group, an EA group, an EA+PI3K antagonist group (EA+P group), and an EA+p38 MAPK agonist+extracellular signal-regulated kinase (ERK) agonist group (EA+M group) (n=8/group). SHRs in EA group, EA+P group and EA+M group received EA treatment 5 sessions per week for continuous 4 weeks, while rats in the normal and model groups were bundled in same condition. The systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) of each rat was measured at 0 week and the 4th week. After 4-week intervention, thoracic aorta was collected for hematoxylin-eosin (HE) staining, immunohistochemistry [the contractile markers α-smooth muscle actin (α-SMA) and calponin and the synthetic marker osteopontin (OPN)] and Western blot [α-SMA, calponin, OPN, PI3K, phosphorylated-Akt (p-Akt), Akt, p-p42/44 ERK, total p42/44 ERK, p-p38 MAPK and total p38 MAPK]. RESULTS: EA significantly reduced SBP, DBP and MAP (P<0.01). HE staining showed that the wall thickness of thoracic aorta in EA group was significantly decreased (P<0.01). From results of immunohistochemistry and Western blot, EA increased the expression of α-SMA and calponin, and decreased the expression of OPN (P<0.01). In addition, the expression of PI3K and p-Akt increased (P<0.01), while the expression of p-p42/44 ERK and p-p38 MAPK decreased in EA group (P<0.01). However, these effects were reversed by PI3K antagonist, p38 MAPK agonist and ERK agonist. CONCLUSIONS: EA was an effective treatment for BP management. The antihypertensive effect of EA may be related with inhibition of phenotypic transformation of VSMCs, in which the activation of PI3K/Akt and the repression of MAPK pathway were involved.

A new species and genus of Alienopteridae (Blattodea) from mid-Cretaceous amber of northern Myanmar.

Eminespina burma gen. et sp. nov., is described and illustrated based on a female embedded in Cretaceous Burmese amber of Cenomanian age. Autapomorphic are three unique spines distributed anterior quarter of pronotum from longer posterior part. The new evidence of Batesian mimicry in the insect fossil record is briefly discussed.

Cellular context- and protein level-dependent interaction of pluripotency factor OCT4A with multiple octamer motifs of the same target gene.

AIMS: To compare how OCT4A proteins interact with and regulate multiple OCT4A-octamer motifs (OMs) in different regions of the FOS gene expressed in somatic cancer cells versus pluripotent stem cells. MATERIALS AND METHODS: Two FOS reporter gene systems harboring predicted OMs or their mutational counterparts were introduced into HeLa and NCCIT cells with varying OCT4A protein levels. The transcription of dsGFP reflecting FOS expression was quantitated by RT-qPCR, the OCT4A-OMs binding and the correlation between OCT4A and FOS transcription was determined by ChIP-PCR and RNA-Seq, respectively. KEY FINDINGS: In NCCIT cells, abundant OCT4A proteins bound to and inhibited OM1 and OM2 at the promoter of the FOS gene. RA-induced OCT4A down-regulation transiently increased FOS transcription. In contrast, in HeLa cells that contain much lower levels of endogenous OCT4A proteins, OCT4A primarily bound to and activate OM1 thereby promoting FOS transcription. OCT4A KO significantly reduced FOS expression. Ectopically introduced OCT4A, at its leaked or induced expression level, promoted FOS transcription by binding to OM2/OM3 or OM1/OM3, respectively. Thus, the interaction of OCT4A proteins with different OMs is cellular context- and protein level-dependent, and such complicated OCT4A binding mode can only be reflected by a dsGFP-based reporter harboring the full-length FOS gene but not by that merely having the FOS promoter. SIGNIFICANCE: Our findings unravel an additional layer of regulatory mechanisms that account for the cellular context- and dose-related versatile functions of OCT4A protein, and further underscore the importance of precise modulation of OCT4A in the regenerative medicine and anticancer therapies.

Deletion of pancreatic ß-cell adenosine kinase improves glucose homeostasis in young mice and ameliorates streptozotocin-induced hyperglycaemia.

Severe reduction in the ß-cell number (collectively known as the ß-cell mass) contributes to the development of both type 1 and type 2 diabetes. Recent pharmacological studies have suggested that increased pancreatic ß-cell proliferation could be due to specific inhibition of adenosine kinase (ADK). However, genetic evidence for the function of pancreatic ß-cell ADK under physiological conditions or in a pathological context is still lacking. In this study, we crossed mice carrying LoxP-flanked Adk gene with Ins2-Cre mice to acquire pancreatic ß -cell ADK deficiency (Ins2-Cre± Adkfl/fl ) mice. Our results revealed that Ins2-Cre+/- Adkfl/fl mice showed improved glucose metabolism and ß-cell mass in younger mice, but showed normal activity in adult mice. Moreover, Ins2-Cre± Adkfl/fl mice were more resistant to streptozotocin (STZ) induced hyperglycaemia and pancreatic ß-cell damage in adult mice. In conclusion, we found that ADK negatively regulates ß-cell replication in young mice as well as under pathological conditions, such as STZ induced pancreatic ß-cell damage. Our study provided genetic evidence that specific inhibition of pancreatic ß-cell ADK has potential for anti-diabetic therapy.

Identification of high expression profiles of miR-31-5p and its vital role in lung squamous cell carcinoma: a survey based on qRT-PCR and bioinformatics analysis.

BACKGROUND: The function of miR-31-5p in lung squamous cell carcinoma (LUSC) remains unclear, therefore, a systematic study was performed for the clinical significance and molecular mechanism of miR-31-5p in LUSC. METHODS: Quantitative real-time reverse transcription PCR (qRT-PCR) was utilized to test the expression level of miR-31-5p in 88 LUSC tissue samples and their matching normal tissues. Data from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) were also utilized to confirm the expression level and clinical value of miR-31-5p in LUSC. The potential target genes of miR-31-5p were predicted by several online predicted software. Gene ontology (GO), protein-protein interaction (PPI) and pathway analysis were utilized to investigate the underlying molecular mechanism of miR-31-5p in LUSC. RESULTS: The result from qRT-PCR found that there was significant difference of miR-31-5p between LUSC and normal tissues (P<0.001). Meanwhile, Data from TCGA also showed a higher expression of miR-31-5p in LUSC tissues than that in the normal tissues (P<0.001). on the basis of the data of GEO database, five GEO datasets indicated that the expression of miR-31-5p in LUSC tissues was significantly higher than that in normal lung tissues, include GSE51858 (P=0.025), GSE74190 (P<0.000), GSE16025 (P=0.031), GSE25508 (P=0.0.01), and GSE47525 (P=0.049). Moreover, in consideration of the meta-analysis, 1,012 clinical specimens were systematically analyzed via meta-analysis, clinical specimens were systematically analyzed via meta-analysis, and the results showed that the expression of miR-31-5p in LUSC was significantly higher than in the adjacent lung tissues (SMD =0, CI: 1.08-1.45, Z=13.30, P=0.000). In addition, result from GO and pathway analyses showed that potential target genes of miR-31-5p were significantly associated with 20 GO terms and 5 pathways, such as signal transduction, transmembrane receptor protein tyrosine kinase activity, plasma membrane and Rap1 signaling pathway. Meanwhile, we also found thatmiR-31-5p target genes were related to the Rap1 signaling pathway, Oxytocin signaling pathway and Proteoglycans in cancer. Furthermore, six hub genes were identified from PPI and three hub genes, including ADCY6, ADCY9 and EGFR, proved to coexist in the Rap1 signaling pathway, oxytocin signaling pathway and Melanogenesis simultaneously. CONCLUSIONS: According to what has been discussed above, we speculated that miR-31-5p may play a vital role in the occurrence and development of LUSC.

SNIP1 Recruits TET2 to Regulate c-MYC Target Genes and Cellular DNA Damage Response.

The TET2 DNA dioxygenase regulates gene expression by catalyzing demethylation of 5-methylcytosine, thus epigenetically modulating the genome. TET2 does not contain a sequence-specific DNA-binding domain, and how it is recruited to specific genomic sites is not fully understood. Here we carried out a mammalian two-hybrid screen and identified multiple transcriptional regulators potentially interacting with TET2. The SMAD nuclear interacting protein 1 (SNIP1) physically interacts with TET2 and bridges TET2 to bind several transcription factors, including c-MYC. SNIP1 recruits TET2 to the promoters of c-MYC target genes, including those involved in DNA damage response and cell viability. TET2 protects cells from DNA damage-induced apoptosis dependending on SNIP1. Our observations uncover a mechanism for targeting TET2 to specific promoters through a ternary interaction with a co-activator and many sequence-specific DNA-binding factors. This study also reveals a TET2-SNIP1-c-MYC pathway in mediating DNA damage response, thereby connecting epigenetic control to maintenance of genome stability.

Induction of multiple cytotoxic T lymphocyte responses in mice by a multiepitope DNA vaccine against dengue virus serotype 1.

Dengue virus (DENV) is still a major threat to human health in most tropical and subtropical countries and regions. In the present study, a multi-epitope DNA vaccine that encodes 15 immunogenic and conserved HLA-A*0201-, HLA-A*1101-, HLA-A*2402-restricted CTL epitopes from DENV serotype 1 (DENV-1) was constructed based on the eukaryotic expressing plasmid pcDNATM 3.1/myc-His(-) A. Immunization of HLA-A*0201, HLA-A*1101 and HLA-A*2402 transgenic mice with the recombinant plasmid pcDNATM 3.1/myc-His(-) A-DENV-1-Meg resulted in significantly greater IFN-γ-secreting T-cell responses against most (14/15) CTL epitopes than occurred in mice immunized with the empty plasmid pcDNATM 3.1/myc-His(-) A. Additionally, the epitope-specific T cells directed to some epitopes secreted not only IFN-γ but also IL-6 and/or TNF-α. Finally, the induced epitope-specific T cells also efficiently lysed epitope-pulsed splenocytes and DENV-1-infected splenic monocytes. The present study confirms the immunogenicity of multi-epitope DENV vaccine, suggesting that it may contribute to the development of a universal DENV vaccine.

Kelch-like Protein 21 (KLHL21) Targets IκB Kinase-ß to Regulate Nuclear Factor κ-Light Chain Enhancer of Activated B Cells (NF-κB) Signaling Negatively.

Activation of IKKß is the key step in canonical activation of NF-κB signaling. Extensive work has provided insight into the mechanisms underlying IKKß activation through the identification of context-specific regulators. However, the molecular processes responsible for its negative regulation are not completely understood. Here, we identified KLHL21, a member of the Kelch-like gene family, as a novel negative regulator of IKKß. The expression of KLHL21 was rapidly down-regulated in macrophages upon treatment with proinflammatory stimuli. Overexpression of KLHL21 inhibited the activation of IKKß and degradation of IκBα, whereas KLHL21 depletion via siRNA showed the opposite results. Coimmunoprecipitation assays revealed that KLHL21 specifically bound to the kinase domain of IKKß via its Kelch domains and that this interaction was gradually attenuated upon TNFα treatment. Furthermore, KLHL21 did not disrupt the interaction between IKKß and TAK1, TRAF2, or IκBα. Also, KLHL21 did not require its E3 ubiquitin ligase activity for IKKß inhibition. Our findings suggest that KLHL21 may exert its inhibitory function by binding to the kinase domain and sequestering the region from potential IKKß inducers. Taken together, our data clearly demonstrate that KLHL21 negatively regulates TNFα-activated NF-κB signaling via targeting IKKß, providing new insight into the mechanisms underlying NF-κB regulation in cells.

A novel mitochondrial DNA deletion in a patient with Pearson syndrome and neonatal diabetes mellitus provides insight into disease etiology, severity and progression.

Pearson syndrome (PS) is a rare, mitochondrial DNA (mtDNA) deletion disorder mainly affecting hematopoietic system and exocrine pancreas in early infancy, which is characterized by multi-organ involvement, variable manifestations and poor prognosis. Since the clinical complexity and uncertain outcome of PS, the ability to early diagnose and anticipate disease progression is of great clinical importance. We described a patient with severe anemia and hyperglycinemia at birth was diagnosed with neonatal diabetes mellitus, and later with PS. Genetic testing revealed that a novel mtDNA deletion existed in various non-invasive tissues from the patient. The disease course was monitored by mtDNA deletion heteroplasmy and mtDNA/nucleus DNA genome ratio in different tissues and at different time points, showing a potential genotype-phenotype correlation. Our findings suggest that for patient suspected for PS, it may be therapeutically important to first perform detailed mtDNA analysis on non-invasive tissues at the initial diagnosis and during disease progression.

Identification of conserved and HLA-A*2402-restricted epitopes in Dengue virus serotype 2.

In this study, we set out to identify dengue virus serotype 2 (DENV-2)-specific HLA-A*2402-restricted epitopes and determine the characteristics of T cells generated to these epitopes. We screened the full-length amino-acid sequence of DENV-2 to find potential epitopes using the SYFPEITHI algorithm. Twelve putative HLA-A*2402-binding peptides conserved in hundreds of DENV-2 strains were synthesized, and the HLA restriction of peptides was tested in HLA-A*2402 transgenic mice. Nine peptides (NS4b(228-237), NS2a(73-81), E(298-306), M(141-149), NS4a(96-105), NS4b(159-168), NS5(475-484), NS1(162-171), and NS5(611-620)) induced high levels of peptide-specific IFN-γ-secreting cells in HLA-A*2402 transgenic mice. Apart from IFN-γ, NS4b(228-237-), NS2a(73-81-) and E(298-306)-specific CD8(+) cells produced TNF-α and IL-6 simultaneously, whereas M(141-149-) and NS5(475-484-) CD8(+) cells produced only IL-6. Moreover, splenic mononuclear cells (SMCs) efficiently recognized and killed peptide-pulsed splenocytes. Furthermore, each of nine peptides could be recognized by splenocytes from DENV-2-infected HLA-A*2402 transgenic mice. The SMCs from HLA-A*2402 transgenic mice immunized with nine immunogenic peptides efficiently killed DENV-2-infected splenic monocytes. The present identified epitopes have the potential to be new diagnostic tools for characterization of T-cell immunity in DENV infection and may serve as part of a universal epitope-based vaccine.

Female specific association between NNMT gene and schizophrenia in a Han Chinese population.

Accumulating evidence has shown that alterations in one carbon metabolism might play an important role in the pathogenesis of schizophrenia (SZ). Nicotinamide-N-methyltransferase (NNMT) is one of the key enzymes of one-carbon metabolism. To examine whether NNMT gene was associated with SZ in Han Chinese population, we selected seven single nucleotide polymorphisms (SNPs) in NNMT gene, and investigated its association with SZ from a cohort of 42 SZ patients and 86 healthy controls by Mass-ARRAY technology. Statistical analyses revealed that one (rs694539) of the SNPs in the female subgroup showed significant difference between SZ patients and controls both in genotypic (p= 0.0170) and allelic frequencies (p = 0.0059). We also found that the frequency of haplotype 'A G G C T C T' in the female patients was significantly higher than in controls (p=0.0015). Our results suggest that NNMT rs694539 may have a role in the etiology of SZ in a Han Chinese female population.