Angiotensin II Enhances Adenylyl Cyclase Signaling via Ca2+/Calmodulin. Gq-Gs Cross-Talk Regulates Collagen Production in Cardiac Fibroblasts

Cardiac fibroblasts regulate formation of extracellular matrix in the heart, playing key roles in cardiac remodeling and hypertrophy. In this study, we sought to characterize cross-talk between Gq and Gs signaling pathways and its impact on modulating collagen synthesis by cardiac fibroblasts. Angiotensin II (ANG II) activates cell proliferation and collagen synthesis but also potentiates cyclic AMP (cAMP) production stimulated by β-adrenergic receptors (β-AR). The potentiation of β-AR-stimulated cAMP production by ANG II is reduced by phospholipase C inhibition and enhanced by overexpression of Gq. Ionomycin and thapsigargin increased intracellular Ca2+ levels and potentiated isoproterenol- and forskolin-stimulated cAMP production, whereas chelation of Ca2+ with 1,2-bis(2-aminophenoxy)ethane-N,N,N′, N′-tetraacetic acid/AM inhibited such potentiation. Inhibitors of tyrosine kinases, protein kinase C, or Gβγ did not alter this cross-talk. Immunoblot analyses showed prominent expression of adenylyl cyclase 3 (AC3), a Ca2+-activated isoform, along with AC2, AC4, AC5, AC6, and AC7. Of those isoforms, only AC3 and AC5/6 proteins were detected in caveolin-rich fractions. Overexpression of AC6 increased βAR-stimulated cAMP accumulation but did not alter the size of the ANG II potentiation, suggesting that the cross-talk is AC isoform-specific. Isoproterenol-mediated inhibition of serum-stimulated collagen synthesis increased from 31 to 48% in the presence of ANG II, indicating that βAR-regulated collagen synthesis increased in the presence of ANG II. These data indicate that ANG II potentiates cAMP formation via Ca2+-dependent activation of AC activity, which in turn attenuates collagen synthesis and demonstrates one functional consequence of cross-talk between Gq and Gs signaling pathways in cardiac fibroblasts

Medium-chain fatty acids suppress lipotoxicity-induced hepatic fibrosis via the immunomodulating receptor GPR84

食事性肥満から肝炎発症に関わる制御因子の同定 --中鎖脂肪酸油による予防・GPR84標的NASH治療薬の可能性--. 京都大学プレスリリース. 2023-01-18.Medium-chain triglycerides (MCTs), which consist of medium-chain fatty acids (MCFAs), are unique forms of dietary fat with various health benefits. G protein–coupled 84 (GPR84) acts as a receptor for MCFAs (especially C10:0 and C12:0); however, GPR84 is still considered an orphan receptor, and the nutritional signaling of endogenous and dietary MCFAs via GPR84 remains unclear. Here, we showed that endogenous MCFA-mediated GPR84 signaling protected hepatic functions from diet-induced lipotoxicity. Under high-fat diet (HFD) conditions, GPR84-deficient mice exhibited nonalcoholic steatohepatitis (NASH) and the progression of hepatic fibrosis but not steatosis. With markedly increased hepatic MCFA levels under HFD, GPR84 suppressed lipotoxicity-induced macrophage overactivation. Thus, GPR84 is an immunomodulating receptor that suppresses excessive dietary fat intake–induced toxicity by sensing increases in MCFAs. Additionally, administering MCTs, MCFAs (C10:0 or C12:0, but not C8:0), or GPR84 agonists effectively improved NASH in mouse models. Therefore, exogenous GPR84 stimulation is a potential strategy for treating NASH

急性期医療を受ける患者の願い

目的：患者の地域での暮らしの希望と療養上の目標を中心に構造化した看護のプロセス”Nursing Care for Patient Goals”（NCPG）に患者の視点から示唆を得るため急性期医療を受ける患者が看護師に知ってほしい情報と療養の目標に対して求める看護を明らかにした． 方法：１特定機能病院において入院中または入院予定の20歳以上の患者を対象として質問紙調査を２回（2017年，2018年）に実施した．調査内容は基本属性，調査Ⅰ（2017年）は先行研究を基に抽出した患者情報23項目について看護師に知って欲しいと思う程度，最も大事と思う項目とその選択理由，調査Ⅱ（2018年）は自分の療養の目標について求める看護であった．統計分析は記述統計，因子分析，t 検定を用いた．自由記述によるデータは質的記述的分析を行った． 結果：調査Ⅰの有効回答数は448名で，看護師に知ってほしい自分の情報として【第１因子：社会的役割と環境】【第２因子：病気の理解・受け入れと心理】【第３因子：身体的状態と生活の仕方】【第４因子：暮らしの希望と自己決定】が抽出された．65歳未満と比較して65歳以上の対象者は第１因子が高い傾向にあった．また第４因子を最も大事と思う項目の選択理由について， “希望・目標がなきゃ生きていけない” という表現が特徴として出された．調査Ⅱの有効回答数は416名で，多数の対象者が自分の目標を医療者と共有することが重要だと感じており，受けたい看護として，傍にいて寄り添う看護，治療・症状への専門的な看護，地域での暮らしの自立への看護が抽出された． 結論：患者の視点から看護師に知ってほしい情報として４つの因子と自分の目標を分ってほしいとする対象者の願いは，希望と目標を基盤としたNCPG の考え方と一致しており，目標達成のために受けたい看護の３つの視点が示唆された．Objective : This study aimed to identify information on care of patients receiving acute care for life in community from the patientsʼ perspective and to obtain suggestions for “Nursing Care for Patient Goals”（NCPG）. Method : The subjects were patients receiving acute care and aged 20 years and above. They were given self-administered questionnaires. Survey Ⅰ（2017）consisted of a questionnaire that was based on previously collected qualitative data and comprised 23 Likert-scale questions and free descriptive questions on the reasons for selecting the most important item. Survey Ⅱ（2018）consisted of questionnaire that was comprised of three Likert-scale questions on goals and a free descriptive question on care for the achievement of goals. Statistical analysis included descriptive statistics, factor analysis, and t-test. Data from free-text descriptions were analyzed using qualitative descriptive analysis. Results : Survey Ⅰ : data from 448 valid responses were subjected to factor analysis to determine the factor structure. The following factors were identified from the patientsʼ perspectives: 1） social role and environment, 2） understanding/acceptance and psychological state, 3） physical condition and life, and 4） hope and decision-making for life. In addition, a qualitative and inductive approach was employed to analyze participantsʼ descriptive responses about the reason for selecting the most important item. The characteristic description of why participants selected “hope and decision-making of life” was “I cannot live without hope.” Survey Ⅱ : data from 416 valid responses were analyzed. The majority of participants felt it was important to share their goals with their healthcare professionals. A qualitative and inductive approach was employed to analyze the participantsʼ descriptive responses to care for goals achievement. The care desired by participants was categorized as “being with”, “professional care”, and “self-care support”. Conclusion : The factors that patients wanted nurses to know were consistent with the components of “NCPG.” The care that patients desire to achieve their goals was clarified

患者の希望を地域につなぐための患者状態とニーズ

目的：急性期医療を受ける患者の地域での生活を視野に入れた看護を展開するために患者の情報と看護の視点について明らかにすることを目的とした． 方法：特定機能病院に勤務する中堅以上の看護師３３名を対象に，地域での生活を視野に入れた患者の情報と看護の視点についてフォーカス・グループ・インタビューを行い分析した． 結果及び考察：急性期医療を受ける患者の地域での生活に必要な情報と看護の視点として，コアカテゴリー《地域での生活を可能にするニーズ》が抽出された．さらに地域での生活を可能にするための状態とニーズとして【身体・生理的な状態とニーズ】，【生活の自立と安全の状態とニーズ】，【病気の受け入れと心理的反応の状態とニーズ】，【社会的環境の状態とニーズ】，【医療・療養への自己決定の状態とニーズ】の５つのカテゴリーに分類された．これらより，患者の暮らしの希望，療養の目標，５つの視点の状態からニーズを導き看護を展開する看護の過程として，“Nursing Care for Patient Goals（” NCPG）を構造化した． 結論：地域包括ケアシステムの中において急性期医療を受ける患者の情報と看護の視点として地域での生活を可能にするための５つの状態とそのニーズが重視されていた．Objective : The aim of this study was to identify information and care perspectives of nurses for patients leaving an acute care hospital for life in the community, and to consider appropriate nursing care in the community-based integrated care system. Method : Focus group interviews were conducted with 33 nurses working in an acute care hospital. The data were analyzed using qualitative inductive analysis. Results & Discussion : The core category “Needs to enable patients to live in the community” was extracted as the information and care perspective necessary for patients receiving acute care to leave hospital for life in the community. The information and care perspectives were classified into five conditions : physical/physiological condition and needs, life independence and safety status and needs, acceptance of/emotions about illness and needs, social environment and needs, and decision-making and needs. “Nursing Care for Patient Goals” was structured as a nursing process. Conclusion : We identified five conditions and their needs that would enable patients receiving acute care to leave hospital for life in the community

Insight into the Regulation of Glycan Synthesis in Drosophila Chaoptin Based on Mass Spectrometry

BACKGROUND: A variety of N-glycans attached to protein are known to involve in many important biological functions. Endoplasmic reticulum (ER) and Golgi localized enzymes are responsible to this template-independent glycan synthesis resulting glycoforms at each asparagine residues. The regulation mechanism such glycan synthesis remains largely unknown. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate the relationship between glycan structure and protein conformation, we analyzed a glycoprotein of Drosophila melanogaster, chaoptin (Chp), which is localized in photoreceptor cells and is bound to the cell membrane via a glycosylphosphatidylinositol anchor. Detailed analysis based on mass spectrometry revealed the presence of 13 N-glycosylation sites and the composition of the glycoform at each site. The synthetic pathway of glycans was speculated from the observed glycan structures and the composition at each N-glycosylation site, where the presence of novel routes were suggested. The distribution of glycoforms on a Chp polypeptide suggested that various processing enzymes act on the exterior of Chp in the Golgi apparatus, although virtually no enzyme can gain access to the interior of the horseshoe-shaped scaffold, hence explaining the presence of longer glycans within the interior. Furthermore, analysis of Chp from a mutant (RNAi against dolichyl-phosphate alpha-d-mannosyltransferase), which affects N-glycan synthesis in the ER, revealed that truncated glycan structures were processed. As a result, the distribution of glycoforms was affected for the high-mannose-type glycans only, whereas other types of glycans remained similar to those observed in the control and wild-type. CONCLUSIONS/SIGNIFICANCE: These results indicate that glycan processing depends largely on the backbone structure of the parent polypeptide. The information we obtained can be applied to other members of the LRR family of proteins

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target

Discovery of widespread transcription initiation at microsatellites predictable by sequence-based deep neural network

Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassigned TSSs and show that, in all species studied, a significant fraction of CAGE peaks initiate at microsatellites, also called short tandem repeats (STRs). To confirm this transcription, we develop Cap Trap RNA-seq, a technology which combines cap trapping and long read MinION sequencing. We train sequence-based deep learning models able to predict CAGE signal at STRs with high accuracy. These models unveil the importance of STR surrounding sequences not only to distinguish STR classes, but also to predict the level of transcription initiation. Importantly, genetic variants linked to human diseases are preferentially found at STRs with high transcription initiation level, supporting the biological and clinical relevance of transcription initiation at STRs. Together, our results extend the repertoire of non-coding transcription associated with DNA tandem repeats and complexify STR polymorphism

α-Glucosidase inhibitors boost gut immunity by inducing IgA responses in Peyer’s patches

Peyer’s patches (PPs) are specialized gut-associated lymphoid tissues that initiate follicular helper T (Tfh)-mediated immunoglobulin A (IgA) response to luminal antigens derived from commensal symbionts, pathobionts, and dietary sources. IgA-producing B cells migrate from PPs to the small intestinal lamina propria and secrete IgA across the epithelium, modulating the ecological balance of the commensal microbiota and neutralizing pathogenic microorganisms. α-glucosidase inhibitors (α-GIs) are antidiabetic drugs that inhibit carbohydrate digestion in the small intestinal epithelium, leading to alterations in the commensal microbiota composition and metabolic activity. The commensal microbiota and IgA responses exhibit bidirectional interactions that modulate intestinal homeostasis and immunity. However, the effect of α-GIs on the intestinal IgA response remains unclear. We investigated whether α-GIs affect IgA responses by administering voglibose and acarbose to mice via drinking water. We analyzed Tfh cells, germinal center (GC) B cells, and IgA-producing B cells in PPs by flow cytometry. We also assessed pathogen-specific IgA responses. We discovered that voglibose and acarbose induced Tfh cells, GCB cells, and IgA-producing B cells in the PPs of the proximal small intestine in mice. This effect was attributed to the modification of the microbiota rather than a shortage of monosaccharides. Furthermore, voglibose enhanced secretory IgA (S-IgA) production against attenuated Salmonella Typhimurium. Our findings reveal a novel mechanism by which α-GIs augment antigen-specific IgA responses by stimulating Tfh-GCB responses in PPs, and suggest a potential therapeutic application as an adjuvant for augmenting mucosal vaccines