High-fat diet induces protein kinase A and G-protein receptor kinase phosphorylation of β2 -adrenergic receptor and impairs cardiac adrenergic reserve in animal hearts.

Key pointsPatients with diabetes show a blunted cardiac inotropic response to β-adrenergic stimulation despite normal cardiac contractile reserve. Acute insulin stimulation impairs β-adrenergically induced contractile function in isolated cardiomyocytes and Langendorff-perfused hearts. In this study, we aimed to examine the potential effects of hyperinsulinaemia associated with high-fat diet (HFD) feeding on the cardiac β2 -adrenergic receptor signalling and the impacts on cardiac contractile function. We showed that 8 weeks of HFD feeding leads to reductions in cardiac functional reserve in response to β-adrenergic stimulation without significant alteration of cardiac structure and function, which is associated with significant changes in β2 -adrenergic receptor phosphorylation at protein kinase A and G-protein receptor kinase sites in the myocardium. The results suggest that clinical intervention might be applied to subjects in early diabetes without cardiac symptoms to prevent further cardiac complications.AbstractPatients with diabetes display reduced exercise capability and impaired cardiac contractile reserve in response to adrenergic stimulation. We have recently uncovered an insulin receptor and adrenergic receptor signal network in the heart. The aim of this study was to understand the impacts of high-fat diet (HFD) on the insulin-adrenergic receptor signal network in hearts. After 8 weeks of HFD feeding, mice exhibited diabetes, with elevated insulin and glucose concentrations associated with body weight gain. Mice fed an HFD had normal cardiac structure and function. However, the HFD-fed mice displayed a significant elevation of phosphorylation of the β2 -adrenergic receptor (β2 AR) at both the protein kinase A site serine 261/262 and the G-protein-coupled receptor kinase site serine 355/356 and impaired adrenergic reserve when compared with mice fed on normal chow. Isolated myocytes from HFD-fed mice also displayed a reduced contractile response to adrenergic stimulation when compared with those of control mice fed normal chow. Genetic deletion of the β2 AR led to a normalized adrenergic response and preserved cardiac contractile reserve in HFD-fed mice. Together, these data indicate that HFD promotes phosphorylation of the β2 AR, contributing to impairment of cardiac contractile reserve before cardiac structural and functional remodelling, suggesting that early intervention in the insulin-adrenergic signalling network might be effective in prevention of cardiac complications in diabetes

<資料>中国における保護者の視点から見た小児がん患児の教育的ニーズの実態 : 河南省鄭州市における検討

本研究は、中国において、長期入院している小児がん患児の保護者への調査を通して、小児がん患児に対する教育の現状と、特別な教育的ニーズを明らかにすることを目的とした。入院している子どもと保護者は、復学について積極的な考え方を持っているものの、学校教育に対する様々な不安感が大きかった。このことから、中国において通常学校での病気のある子どもに対する心理的支援、病気に対する理解などの必要性が明らかとなった。また、現在の中国における病院内の病棟学級は教育的な機能が不足しており、入院児の保護者の理解や認識も十分ではなかった。病棟学級の教育担当者の専門性のより一層の向上と医療との連携にもとづき、今後、中国においても病棟学級の教育内容の充実を図っていくことが必要であると思われた。The study aims to clarify the educational situation and special educational needs of children with cancer through an investigation into parents whose children have long-term hospitalization in China. Parents and their children who are hospitalized have a positive attitude to school recovery, but they are worried about the life of school recovery. Thus, the consideration of understanding children’s condition and improving psychological supports should be emphasized during school recovery. On the other hand, in China, hospital classrooms do not have enough educational function and parents do not understand hospital classrooms very well. Hospital classroom teachers should improve expertise and collaboration with hospitals, which is important for hospital classrooms in China to enrich their educational content

Design, synthesis and pharmacological evaluation of tricyclic derivatives as selective RXFP4 agonists

Relaxin family peptide receptors (RXFPs) are the potential therapeutic targets for neurological, cardiovascular, and metabolic indications. Among them, RXFP3 and RXFP4 (formerly known as GPR100 or GPCR142) are homologous class A G protein-coupled receptors with short N-terminal domain. Ligands of RXFP3 or RXFP4 are only limited to endogenous peptides and their analogues, and no natural product or synthetic agonists have been reported to date except for a scaffold of indole-containing derivatives as dual agonists of RXFP3 and RXFP4. In this study, a new scaffold of tricyclic derivatives represented by compound 7a was disclosed as a selective RXFP4 agonist after a high-throughput screening campaign against a diverse library of 52,000 synthetic and natural compounds. Two rounds of structural modification around this scaffold were performed focusing on three parts: 2-chlorophenyl group, 4-hydroxylphenyl group and its skeleton including cyclohexane-1,3-dione and 1,2,4-triazole group. Compound 14b with a new skeleton of 7,9-dihydro-4H-thiopyrano[3,4-d][1,2,4]triazolo[1,5-a]pyrimidin-8(5H)-one was thus obtained. The enantiomers of 7a and 14b were also resolved with their 9-(S)-conformer favoring RXFP4 agonism. Compared with 7a, compound 9-(S)-14b exhibited 2.3-fold higher efficacy and better selectivity for RXFP4 (selective ratio of RXFP4 vs. RXFP3 for 9-(S)-14b and 7a were 26.9 and 13.9, respectively)

The first prospective application of AIGS real-time fluorescence PCR in precise diagnosis and treatment of meningioma: Case report

BackgroundThe emergence of the new WHO classification standard in 2021 incorporated molecular characteristics into the diagnosis system for meningiomas, making the diagnosis and treatment of meningiomas enter the molecular era.Recent findingsAt present, there are still some problems in the clinical molecular detection of meningioma, such as low attention, excessive detection, and a long cycle. In order to solve these clinical problems, we realized the intraoperative molecular diagnosis of meningioma by combining real-time fluorescence PCR and AIGS, which is also the first known product applied to the intraoperative molecular diagnosis of meningioma.Implications for practiceWe applied AIGS to detect and track a patient with TERTp mutant meningioma, summarized the process of intraoperative molecular diagnosis, and expounded the significance of intraoperative molecular diagnosis under the new classification standard, hoping to optimize the clinical decision-making of meningioma through the diagnosis and treatment plan of this case

Genetically Encoded Biosensors Reveal PKA Hyperphosphorylation on the Myofilaments in Rabbit Heart Failure

RATIONALE: In heart failure, myofilament proteins display abnormal phosphorylation, which contributes to contractile dysfunction. The mechanisms underlying the dysregulation of protein phosphorylation on myofilaments is not clear. OBJECTIVE: This study aims to understand the mechanisms underlying altered phosphorylation of myofilament proteins in heart failure. METHODS AND RESULTS: We generate a novel genetically encoded protein kinase A (PKA) biosensor anchored onto the myofilaments in rabbit cardiac myocytes to examine PKA activity at the myofilaments in responses to adrenergic stimulation. We show that PKA activity is shifted from the sarcolemma to the myofilaments in hypertrophic failing rabbit myocytes. In particular, the increased PKA activity on the myofilaments is because of an enhanced β2 adrenergic receptor signal selectively directed to the myofilaments together with a reduced phosphodiesterase activity associated with the myofibrils. Mechanistically, the enhanced PKA activity on the myofilaments is associated with downregulation of caveolin-3 in the hypertrophic failing rabbit myocytes. Reintroduction of caveolin-3 in the failing myocytes is able to normalize the distribution of β2 adrenergic receptor signal by preventing PKA signal access to the myofilaments and to restore contractile response to adrenergic stimulation. CONCLUSIONS: In hypertrophic rabbit myocytes, selectively enhanced β2 adrenergic receptor signaling toward the myofilaments contributes to elevated PKA activity and PKA phosphorylation of myofilament proteins. Reintroduction of caveolin-3 is able to confine β2 adrenergic receptor signaling and restore myocyte contractility in response to β adrenergic stimulation

Molecular basis of ligand recognition and activation of human V2 vasopressin receptor.

Vasopressin type 2 receptor (V2R) belongs to the vasopressin (VP)/oxytocin (OT) receptor subfamily of G protein-coupled receptors (GPCRs), which comprises at least four closely related receptor subtypes: V1aR, V1bR, V2R, and OTR. These receptors are activated by arginine vasopressin (AVP) and OT, two endogenous nine-amino acid neurohypophysial hormones, which are thought to mediate a biologically conserved role in social behavior and sexual reproduction. V2R is mainly expressed in the renal collecting duct principal cells and mediates the antidiuretic action of AVP by accelerating water reabsorption, thereby playing a vital role in controlling water homeostasis. Moreover, numerous gain-of-function and loss-of-function mutations of V2R have been identified and are closely associated with human diseases, including nephrogenic syndrome of inappropriate diuresis (NSIAD) and X-linked congenital nephrogenic diabetes insipidus (NDI). Thus, V2R has attracted intense interest as a drug target. However, due to a lack of structural information, how AVP recognizes and activates V2R remains elusive, which hampers the V2R-targeted drug design. Here, we determined a 2.6 Å resolution cryo-EM structure of the full-length, G s -coupled human V2R bound to AVP (Fig. 1a; Supplementary information, Table S1). The G s protein was engineered based on mini-G s that was used in the crystal structure determination of the G s -coupled adenosine A 2A receptor (A 2A R) to stabilize the V2R–G s protein complex (Supplementary information, Data S1). The final structure of the AVP–V2R–G s complex contains all residues of AVP (residues 1–9), the Gα s Ras-like domain, Gβγ subunits, Nb35, scFv16, and the V2R residues from T31 to L339 8.57 (superscripts refer to Ballesteros–Weinstein numbering). The majority of amino acid side chains, including AVP, transmembrane domain (TMD), all flexible intracellular loops (ICLs) and extracellular loops (ECLs) except for ICL3 and G185–G188 in ECL2, were well resolved in the model, refined against the EM density map (Fig. 1a; Supplementary information, Figs. S1–3). The complex structure can provide detailed information on the binding interface between AVP and helix bundle of the receptor, as well as the receptor–G s interface

Bidirectional Role of β2-Adrenergic Receptor in Autoimmune Diseases

Disorder of the sympathetic nervous system (SNS) is closely related to the pathogenesis of various autoimmune diseases (ADs). Catecholamine triggered beta2-adrenergic receptor (β2-AR) signaling is important in creating a bidirectional response in the progression of ADs due to factors including diverse expression patterns, single nucleotide polymorphisms (SNPs), biased signals, and desensitization of β2-AR, as well as different subtypes of Gα binding to β2-AR. In this review, we summarize the actions of β2-AR signaling in regulating the functions of immunocytes and in the pathogenesis of ADs, and the application of β2-AR agonists or antagonists in treating major types of ADs is also discussed. We suggest that restoring the immune balance via a soft regulation of the expression or activation of β2-AR is one of the promising therapeutic strategies for systematic ADs

Photoluminescent Cationic Carbon Dots as efficient Non-Viral Delivery of Plasmid SOX9 and Chondrogenesis of Fibroblasts

With the increasing demand for higher gene carrier performance, a multifunctional vector could immensely simplify gene delivery for disease treatment; nevertheless, the current non- viral vectors lack self-tracking ability. Here, a type of novel, dual-functional cationic carbon dots (CDs), produced through one-step, microwave-assisted pyrolysis of arginine and glucose, have been utilized as both a self-imaging agent and a non-viral gene vector for chondrogenesis from fibroblasts. The cationic CDs could condense the model gene plasmid SOX9 (pSOX9) to form ultra-small (10–30 nm) nanoparticles which possessed several favorable properties, including high solubility, tunable fluorescence, high yield, low cytotoxicity and outstanding biocompatibility. The MTT assay indicated that CDs/pSOX9 nanoparticles had little cytotoxicity against mouse embryonic fibroblasts (MEFs) compared to Lipofectamine2000 and PEI (25 kDa). Importantly, the CDs/pSOX9 nanoparticles with tunable fluorescence not only enabled the intracellular tracking of the nanoparticles, but also could successfully deliver the pSOX9 into MEFs with significantly high efficiency. Furthermore, the CDs/pSOX9 nanoparticles-mediated transfection of MEFs showed obvious chondrogenic differentiation. Altogether, these findings demonstrated that the CDs prepared in this study could serve as a paradigmatic example of the dual-functional reagent for both self-imaging and effective non-viral gene delivery

A new method for the characterization of microcracks based on seepage characteristics

Microcracks are the main seepage channels and reservoir space for oil and gas in dense sandstone reservoirs, and the degree of development dominates the reservoir’s high and stable production capacity. A new method has been devised to address the lack of quantitative identification and characterization methods for microcrack networks. The method is based on core stress sensitivity, permeability anisotropy, and two-phase seepage rule testing. By improving upon the traditional black oil model, this method can accurately calculate the impact that microcracks of varying degrees of development have on the capacity of tight oil reservoirs. The study shows that 1) the higher the degree of microcrack development, the stronger the reservoir stress sensitivity and the greater the permeability anisotropy. As the degree of microcrack development increases, the irreducible water saturation decreases, the residual oil saturation gradually increases, and the oil–water two-phase co-infiltration zone becomes more extensive and smaller. The degree of microcrack development in tight reservoirs can be characterized based on the seepage characteristic parameters; 2) a microcrack characterization method and classification criteria have been established. It is based on stress sensitivity coefficients, permeability anisotropy parameters, and phase seepage characteristics in cores with different microcrack development degrees. For the first time, the method enables a macroscopic-level description of microcrack seepage; 3) numerical calculations show that the degree of microcrack development significantly affects the reservoir’s oil production and water production. The higher the degree of microcrack development, the higher the reservoir’s initial oil production and cumulative oil production. However, when the degree of microcrack development is too high, the microcracks are connected, thus exhibiting the nature of large fractures. This strengthens the bypassing communication effect and causes the microscopic inhomogeneity to strengthen, the oil production decreases rapidly, and water production increases quickly at the later stage. This research result enriches the reservoir microcrack characterization and evaluation system, which has essential theoretical guidance and practical significance for the rational and effective development of tight oil and tight sandstone gas