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β(1) adrenergic receptors (β(1)ARs) are central regulators of cardiac function and a drug target for cardiac disease. As a member of the G protein–coupled receptor family, β(1)ARs activate cellular signaling by primarily coupling to Gs proteins to activate adenylyl cyclase, cAMP-dependent pathways, and the multifunctional adaptor-transducer protein β-arrestin. Carvedilol, a traditional β-blocker widely used in treating high blood pressure and heart failure by blocking β adrenergic receptor–mediated G protein activation, can selectively stimulate Gs-independent β-arrestin signaling of β adrenergic receptors, a process known as β-arrestin–biased agonism. Recently, a DNA-encoded small-molecule library screen against agonist-occupied β(2) adrenergic receptors (β(2)ARs) identified Compound-6 (Cmpd-6) to be a positive allosteric modulator for agonists on β(2)ARs. Intriguingly, it was further discovered that Cmpd-6 is positively cooperative with the β-arrestin–biased ligand carvedilol at β(2)ARs. Here we describe the surprising finding that at β(1)ARs unlike β(2)ARs, Cmpd-6 is cooperative only with carvedilol and not agonists. Cmpd-6 increases the binding affinity of carvedilol for β(1)ARs and potentiates carvedilol-stimulated, β-arrestin–dependent β(1)AR signaling, such as epidermal growth factor receptor transactivation and extracellular signal-regulated kinase activation, whereas it does not have an effect on Gs-mediated cAMP generation. In vivo, Cmpd-6 enhances the antiapoptotic, cardioprotective effect of carvedilol in response to myocardial ischemia/reperfusion injury. This antiapoptotic role of carvedilol is dependent on β-arrestins since it is lost in mice with myocyte-specific deletion of β-arrestins. Our findings demonstrate that Cmpd-6 is a selective β-arrestin–biased allosteric modulator of β(1)ARs and highlight its potential clinical utility in enhancing carvedilol-mediated cardioprotection against ischemic injury. SIGNIFICANCE STATEMENT: This study demonstrates the positive cooperativity of Cmpd-6 on β(1)ARs as a β-arrestin–biased positive allosteric modulator. Cmpd-6 selectively enhances the affinity and cellular signaling of carvedilol, a known β-arrestin–biased β-blocker for β(1)ARs, whereas it has minimal effect on other ligands tested. Importantly, Cmpd-6 enhances the β-arrestin–dependent in vivo cardioprotective effect of carvedilol during ischemia/reperfusion injury–induced apoptosis. The data support the potential therapeutic application of Cmpd-6 to enhance the clinical benefits of carvedilol in the treatment of cardiac disease.

As one of the main food bamboo species of the giant panda (Ailuropoda melanoleuca), Fargesia denudata is widely distributed in the understory of spruce–fir forests in the mountainous area of southwestern China. However, the driving factors of its biomass and distribution in the forests are still unclear. We conducted a systematic investigation of the tree and shrub layers (including bamboos) of 209 subplots (20 m × 20 m) in a Forest Global Earth Observatory plot, the Wanglang Plot (25.2 ha), to explore the effects of abiotic (topographic and soil characteristics) and biotic (tree density, total basal area (TBA), shrub coverage, etc.) factors on the aboveground biomass of F. denudata (bamboo biomass hereafter). Bamboo biomass averaged 1.17 ton/ha, with a large variation from 0 to 4.88 ton/ha (95% confidence interval) among the 209 subplots. Bamboo biomass increased significantly with elevation, slope and mean diameter at breast height of trees, and decreased significantly with tree density, shrub coverage and soil pH. However, bamboo biomass was not significantly correlated with tree TBA, aspect, soil organic matter or total nitrogen content. The random forest model indicated that topographic factors and biotic factors had greater influences on the bamboo biomass than soil characteristics in general. Specifically, topographic factors mainly affected the bamboo biomass by changing tree density and soil characteristics. Our results can provide valuable guidance for the protection of giant pandas and the management of subalpine spruce–fir forests.

This study seeks to discover the change of cloud's expansion rate with self-designed shock wave dispersion system. Transmission, diffraction and reflection could be observed intuitively when shock waves passed through solid particle layers. Results show that the longitudinal motion of particle group greatly influenced cloud's volume growth, thus, the maximum rate of longitudinal expansion of clouds was almost twice that of lateral expansion. The cloud growth rate and volume acceleration increased with smaller particle size, thicker particle layer and stronger shock wave intensity. Also, the expansion rate initially had a drastic decrease, small particles made clouds volume acceleration unstable and experienced a subsequent swift rise. Shock wave intensity influenced diffraction and reflection formation waves as well as the cloud's shape and expansion rate. This study therefore proposed a controlling model for cloud's expansion rate, which could illustrate differences between acceleration stage of dynamic action and deceleration stage of resistance action.

RationaleModulation of endothelial cell behavior and phenotype by hemodynamic forces involves many signaling components, including cell surface receptors, intracellular signaling intermediaries, transcription factors, and epigenetic elements. Many of the signaling mechanisms that underlie mechanotransduction by endothelial cells are inadequately defined.ObjectiveWe sought to better understand how β-arrestins, intracellular proteins that regulate agonist-mediated desensitization and integration of signaling by transmembrane receptors, may be involved in the endothelial cell response to shear stress.Methods and ResultsIn vitro studies with primary endothelial cells subjected to β-arrestin knockdown, and in vivo studies using mice with endothelial specific deletion of β-arrestin 1 and β-arrestin 2 were conducted. We found that β-arrestins are localized to primary cilia in endothelial cells, which are present in subpopulations of endothelial cells in relatively low shear states. Recruitment of β-arrestins to cilia involved its interaction with IFT81, a component of the flagellar transport protein complex in the cilia. β-arrestin knockdown led to marked reduction in shear stress response, including induction of NOS3 expression. Within the cilia, β-arrestins were found to associate with the type II bone morphogenetic protein receptor (BMPR-II), whose disruption similarly led to an impaired endothelial shear response. β-arrestins also regulated Smad transcription factor phosphorylation by BMPR-II. Mice with endothelial specific deletion of β-arrestin 1 and β-arrestin 2 were found to have impaired retinal angiogenesis.ConclusionWe have identified a novel role for endothelial β-arrestins as key transducers of ciliary mechanotransduction that play a central role in shear signaling by BMPR-II and contribute to vascular development.NOVELTY AND SIGNIFICANCEWhat Is Known?Endothelial cells respond to flow-induced shear stress with biochemical changes, such as phosphorylation of endothelial nitric oxide synthase, that promote morphological changes, such as cell alignment.The endothelial response to shear stress can involve primary cilia, microtubule-based sensory organelles that detect extracellular stimuli and generates intracellular signals.The specific ciliary signaling pathways that regulate endothelial mechanotransduction have not been fully elucidated.What New Information Does This Article Contribute?β-arrestins directly interact with the ciliary protein intraflagellar transport protein 81 (IFT81), which is present in the primary cilia of endothelial cells, and are required for the morphological response to flow-induced shear stress.β-arrestins regulates type II bone morphogenetic protein receptor signaling, which is required for the endothelial response to shear stress, and is required for the phosphorylation of Smad transcription factors.β-arrestins are required for endothelial nitric oxide synthase-mediated flow-induced shear stress response in endothelial cells.Endothelial cell-specific knockout of β-arrestins results in abnormal vascular development, with a loss of vessel length and branchpoints.

Purpose The local microclimate of different slope aspects in the same area can not only impact soil environment and plant community but also affect soil microbial community. However, the relationship between aboveground plant communities and belowground soil microbial communities on various slope aspects has not been well understood.Methods We investigated the above- and belowground relationship on different slope aspects and explored how soil properties influence this relationship. Plant community attributes were evaluated by plant species richness and plant total basal area. Soil microbial community was assessed based on both 16S rRNA and ITS rRNA, using High-throughput Illumina sequencing. Results There was no significant correlation between plant richness and soil bacterial community composition on the north slope, but there was a positive correlation on the south slope and a significantly negative correlation on the flat site. There was a significantly negative correlation between soil fungal community composition and plant total basal area, which did not change with the slope aspect. In addition, there was no significant correlation between plant community species richness and soil microbial species richness.Conclusions In subalpine coniferous forests, the relationship between plant-soil bacteria varies with slope aspect, but the plant-soil fungi relationship is relatively consistent across different slope aspects. These results can improve our understanding of the relationship between plant and soil microorganisms in forest ecosystems under microtopographic changes and have important implications for the conservation of biodiversity and forest management in subalpine coniferous forests.

Background: Wu-Mei-Wan (WMW), a traditional Chinese medicine (TCM) formula, has a good effect on the treatment of obesity and has been proven helpful to promote the metabolism of adipose tissue. However, its underlying mechanism remains to be studied. This study aims to explore the potential pharmacological mechanism of WMW in the treatment of obesity. Methods: Network pharmacology was used to sort out the relationship between WMW putative targets and obesity-related drug targets or disease targets, which indicated the mechanism of WMW in treating obesity from two aspects of clinical drugs approved by the Food and Drug Administration (FDA) and obesity-related diseases. Databases such as Traditional Chinese Medicine Systems Pharmacology (TCMSP), PubChem, DrugBank, DisGeNET, and Genecards were used to collect information about targets. String platform was used to convert the data into gene symbol of “homo sapiens”, and perform gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. With the Human Protein Reference Database (HPRD) as background data, Cytoscape 3.6.0 software was used to construct a new protein-protein interaction (PPI) network. Mechanism diagrams of key pathways were obtained from the KEGG database. AutoDock Vina software was used to conduct molecular docking verification. Results: The number of targets in the overlap between WMW putative targets and obesity-related drug targets accounted for more than 50% of the latter, and HTR3A, SLC6A4, and CYP3A4 were core targets. In obesity-related disease targets-WMW putative targets PPI network, the Th17 cell differentiation pathway, and the IL-17 signaling pathway were key pathways, and the 1st module and the 7th module were central function modules that were highly associated with immunity and inflammation. Molecular docking verified that STAT3, TGFB1, MMP9, AHR, IL1B, and CCL2 were core targets in the treatment of WMW on obesity. Conclusion: WMW has similar effects on lipid and drug metabolism as the current obesity-related drugs, and is likely to treat obesity by inhibiting Th17 cell differentiation and alleviating metabolic inflammation.

HuanglianGanjiang Tang (HGT) is a classic prescription of traditional Chinese medicine (TCM) recorded in Dan Xi Xin Fa, which was used to alleviate manifestations like diarrhea, abdominal pain and hemafecia. In current clinical practices, HGT is adopted for the treatment of ulcerative colitis (UC) and affords good curative effect. However, the underlying mechanism deserves further elucidation.UC is a hard-to-curable and easy-to-recurrent inflammatory disease. This study is to evaluate the potential therapeutics and explore the molecular mechanism of HGT on UC in the mouse model.The components of HGT extracts were identified by HPLC. The colitis of mice was induced by 3% (w./v.) dextran sulfate sodium (DSS). The HGT decoction was prepared through boiling and centrifuging. The mice were given HGT decoction via oral gavage (0.34 g/ml0.68 g/ml; 5 ml/kg b.w.). The protective role of HGT on colitis mice was evaluated by body weight change, colon length, disease activity index (DAI) and histological scores. The expressions of necroptosis-related and vitamin D receptor (VDR)-related proteins were measured by Western blot, RT-qPCR and immunofluorescence.HGT could significantly reduce the loss of body weight and colon length in colitis mice, and alleviated the DAI and histological scores. Mechanically, HGT also promoted the expression of E-cadherin, Occludin, ZO-1 and VDR, and reduced the level of intestinal inflammatory cytokines, such as, IL-6, IL-1β and TNF-α. Besides, HGT downregulated the protein level of p-RIPK3, p-RIPK1 and p-MLKL while upregulated the protein level of Caspase-8 in colon tissue compared to the model group.Our study addressed that HGT can alleviate DSS-induced colitis of mice through inhibiting colonic necroptosis by upregulating the level of VDR.

Background Extending service scope of primary care facilities (PCFs) has been widely concerned in China. However, no current data about association between service scope of PCFs with patient outcomes are available. This study aims to investigate association between service scope of PCFs and patient outcomes. Methods A multistage, stratified clustered sampling method was used to collect information about service scope of PCFs from rural Guizhou, China. Claim data of 299,633 inpatient cases covered by 64 PCFs were derived from local information system of New Rural Cooperation Medical Scheme. Service scope of PCFs was collected with self-administrated questionnaires. Primary outcomes were (1) level of inpatient institutions, (2) length of stay, (3) per capita total health cost, (4) per capita out-of-pocket cost, (5) reimbursement ratio, (6) 30-day readmission. A total of 64 PCFs were categorized into five groups per facility-level service scope scores. Generalized linear regression models, logistic regression model, and ordinal regression model were conducted to identify association between service scope of PCFs and patient outcomes. Results On average, the median service scope score of PCFs was 20, with wide variation across PCFs. After controlling for demographic and clinical characteristics, patients living in communities with PCFs of greatest service scope (Quintile V vs. I) tended to have smaller rates of admission by county-level hospitals (-6.2 % [-6.5 %, -5.9 %], city-level hospitals (-1.9 % [-2.0 %, -1.8 %]), and provincial hospitals (-2.1 % [-2.2 %, -2.0 %]), smaller rate of 30-day readmission (-0.5 % [-0.7 %, -0.2 %]), less total health cost (-201.8 [-257.9, -145.8]) and out-of-pocket cost (-210.2 [-237.2, -183.2]), and greater reimbursement ratio (2.3 % [1.9 %, 2.8 %]) than their counterparts from communities with PCFs of least service scope. Conclusions Service scope of PCFs varied a lot in rural Guizhou, China. Greater service scope was associated with a reduction in secondary and tertiary hospital admission, reduced total cost and out-of-pocket cost, and 30-day readmission and increased reimbursement ratio. These results raised concerns about access to care for patients discharged from hospitals, which suggests potential opportunities for cost savings and improvement of quality of care. However, further evidence is warranted to investigate whether extending service scope of PCFs is cost-effective and sustainable.

BackgroundAccumulating evidence indicated that necroptosis plays an essential role in the pathogenesis of inflammatory bowel disease (IBD). TheO-linked β-N-acetylglucosaminylation (O-GlcNAcylation) of necroptotic signal molecule receptor-interacting serine-threonine kinase 3 (RIPK3) was reported to exert a protective effect in gut inflammation. Our recent study suggested traditional Chinese herbal formula Wu-Mei-Wan (WMW) as an effective prescription in mouse colitis. However, the potential mechanisms are not fully understood. Considering the crucial role of necroptosis in the pathogenesis of IBD, therefore, this study was designed to explain whether the anti-colitis effect of WMW is mediated by modulating necroptosis and its related mechanisms.MethodsThe protective effects of WMW on colitis have been determined by detecting colitis mice body weight, disease activity index (DAI), survival rate and colon length. Colonic inflammation was examined by inflammatory cells infiltration and local cytokines levels. After then, we measured the levels of necroptosis andO-GlcNAcylation. CO-immunoprecipitation experiments were used to address whether elevatedO-GlcNAcylation can inhibit necroptotic signal transduction in the treatment of WMW. Finally, the key enzymes inO-GlcNAcylation:O-GlcNAc transferase (OGT) andO-GlcNAcase (OGA) were examined and molecular docking analysis was used to determine effective natural compounds in the regulation on OGT and OGA activities.ResultsOur results showed that WMW significantly improved mice body weight, survival rate and colon length, decreased DAI in TNBS-induced colitis. WMW obviously alleviated colonic inflammatory responses with reduced macrophages, neutrophils infiltration and local IL-1β, IL-6, TNF-α and IFN-γ levels. It was found that WMW increased colonicO-GlcNAcylation level and inhibited the activation of RIPK1, RIPK3 and MLKL. Then, further experiments revealed that WMW enhanced OGT activity and suppressed OGA activity, thereby increasing RIPK3O-GlcNAcylation and inhibiting the binding of RIPK3 and MLKL, which led to the inhibition of necroptosis. Additionally, docking analysis demonstrated that hesperidin, coptisine and ginsenoside Rb1 may exert a major role in the regulation on OGT and OGA activities by WMW.ConclusionOur work demonstrated that WMW can alleviate TNBS-induced colitis in mice by inhibiting necroptosis through increasing RIPK3O-GlcNAcylation.

Lakes have played a critical role in providing water and ecosystem services for people and other organisms in China for millennia. However, accelerating climate change and economic boom have resulted in unprecedented changes in these valuable lakes. Using Landsat images covering the entity of the country, we explored the changes in China’s lakes and the associated driving forces over the last 30 years (i.e. mid-1980s to 2015). We discovered that China’s lakes have changed with divergent regional trends: in the sparsely populated Tibetan Plateau, lakes are abundant and the lake area has increased dramatically from 38 596 to 46 831 km2 (i.e. increased by 8235 km2, or 21.3%), whereas, in the densely populated northern and eastern regions, lakes are relatively scarce and the lake area has decreased from 36 659 to 33 657 km2 (i.e. decreased by 3002 km2, or 8.2%). In particular, severe lake decreases occurred in the Mongolia-Xinjiang Plateau and the Eastern Plain (−2151 km2). Statistical analyses indicated that climate was the most important factor controlling lake changes in the Tibetan Plateau, the Yun-Gui Plateau and the Northeast Plain. However, the strength of climatic control on lake changes was low in the Eastern Plain and the Mongolia-Xinjiang Plateau, where human activities, e.g. impoldering, irrigation and mining, have caused serious impacts on lakes. Further lake changes will exacerbate regional imbalances between lake resources and population distribution, and thus may increase the risk of water-resource crises in China.

Background: Receptor signaling is central to vascular endothelial function and is dysregulated in vascular diseases such as atherosclerosis and pulmonary arterial hypertension (PAH). Signaling pathways involved in endothelial function include vascular endothelial growth factor receptors (VEGFRs) and G protein–coupled receptors, which classically activate distinct intracellular signaling pathways and responses. The mechanisms that regulate these signaling pathways have not been fully elucidated and it is unclear what nodes for cross talk exist between these diverse signaling pathways. For example, multifunctional β-arrestin (ARRB) adapter proteins are best known as regulators of G protein–coupled receptor signaling, but their role at other receptors and their physiological importance in the setting of vascular disease are unclear. Methods: We used a combination of human samples from PAH, human microvascular endothelial cells from lung, and Arrb knockout mice to determine the role of ARRB1 in endothelial VEGFR3 signaling. In addition, a number of biochemical analyses were performed to determine the interaction between ARRB1 and VEGFR3, signaling mediators downstream of VEGFR3, and the internalization of VEGFR3. Results: Expression of ARRB1 and VEGFR3 was reduced in human PAH, and the deletion of Arrb1 in mice exposed to hypoxia led to worse PAH with a loss of VEGFR3 signaling. Knockdown of ARRB1 inhibited VEGF-C–induced endothelial cell proliferation, migration, and tube formation, along with reduced VEGFR3, Akt, and endothelial nitric oxide synthase phosphorylation. This regulation was mediated by direct ARRB1 binding to the VEGFR3 kinase domain and resulted in decreased VEGFR3 internalization. Conclusions: Our results demonstrate a novel role for ARRB1 in VEGFR regulation and suggest a mechanism for cross talk between G protein–coupled receptors and VEGFRs in PAH. These findings also suggest that strategies to promote ARRB1-mediated VEGFR3 signaling could be useful in the treatment of pulmonary hypertension and other vascular disease.

Background Endothelin-1 (ET-1) is a potent vasoconstrictor in the cardiovascular system, an effect mediated through the type A endothelin receptor (ETAR), a G protein-coupled receptor (GPCR). Antagonists of the ETAR have shown promising results in randomized clinical trials. However, side effects limit widespread use. Biased agonists have been developed to mitigate the untoward effects of a number of GPCR antagonists. These agents block deleterious G-coupled pathways while stimulating protective β-arrestin pathways. The goal of this study was to test whether there was any significant ligand bias between endothelin derivatives, and whether this could have any physiologic effects in the cardiovascular system. Methods A panel of endothelin derivatives were tested in assays of G protein signaling and β-arrestin 2 recruitment at the ETAR. We then tested the effects of ET-1 on the vasopressor response in wild-type and β-arrestin 1 and 2 KO mice. Results We found the endothelins activated a wide range of G proteins at the ETAR, but none of the endothelin derivatives demonstrated significant biased agonism. Endothelin derivatives did display structure-activity relationships with regards to their degrees of agonism. β-arrestin 1 and 2 knockout mice did not display any differences to wild-type mice in the acute pressor response to ET-1, and β-arrestin 2 knockout mice did not display any blood pressure differences to wild-type mice in the chronic responses to ET-1. Conclusions Our findings are consistent with vasoconstriction being mediated by G proteins with a lack of significant desensitization by β-arrestins at the ETAR. These findings suggest that G protein– and β-arrestin–biased ETAR agonists could have distinct physiologic effects from balanced agonists, although the endothelin peptide scaffold does not appear suitable for designing such ligands.

Visual Abstract, Highlights • We tested the effects of a β-arrestin–biased agonist (TRV023) of the angiotensin II (AngII) type 1 receptor (AT1R), which acts as a vasodilator while not blocking cellular proliferation, compared to a balanced agonist, AngII, and an antagonist, losartan, in PAH. • In acute infusion, AngII increased right ventricular pressures while TRV023 and losartan did not. However, in chronic infusion in monocrotaline PAH rats, both TRV023 and AngII had significantly worse survival than losartan. • Both TRV023 and AngII enhanced proliferation and migration of pulmonary artery smooth muscle cells from patients with PAH. • β-arrestin-mediated AT1R signaling promotes vascular remodeling and worsens PAH, and suggests that the benefit of current PAH therapies is primarily through pulmonary vascular reverse remodeling., Summary Pulmonary arterial hypertension (PAH) is a disease of abnormal pulmonary vascular remodeling whose medical therapies are thought to primarily act as vasodilators but also may have effects on pulmonary vascular remodeling. The angiotensin II type 1 receptor (AT1R) is a G protein–coupled receptor that promotes vasoconstriction through heterotrimeric G proteins but also signals via β-arrestins, which promote cardioprotective effects and vasodilation through promoting cell survival. We found that an AT1R β-arrestin-biased agonist promoted vascular remodeling and worsened PAH, suggesting that the primary benefit of current PAH therapies is through pulmonary vascular reverse remodeling in addition to their vasodilation.

ObjectivesThe goal of this study was to test whether a β-arrestin-biased agonist of the angiotensin II (AngII) type 1 receptor (AT1R), which acts as a vasodilator while not blocking cellular proliferation, would have positive effects compared to a balanced agonist, angiotensin II (AngII), or an antagonist, losartan, in pulmonary arterial hypertension (PAH).BackgroundPAH is a disease of abnormal pulmonary vascular remodeling whose treatment has focused on targeting vasoactive substances, such as inhibiting endothelin signaling and promoting prostacyclin signaling. PAH medical therapies are thought to primarily act as vasodilators, although they may also have effects on pulmonary vascular remodeling. There are a number of reports that blocking AT1R signaling can be beneficial in preclinical models of PAH. The AT1R is a G protein-coupled receptor (GPCR) that promotes vasoconstriction through heterotrimeric G proteins but also signals via β-arrestins, which promote cardioprotective effects and vasodilation.MethodsWe compared the effects of a β-arrestin-biased AT1R agonist, TRV120023 (TRV023), to a balanced agonist (AngII) and an antagonist (losartan) in preclinical PAH models.ResultsIn acute infusion studies, AngII increased right ventricular (RV) pressures while TRV023 did not. However, with chronic infusion in monocrotaline (MCT) PAH rats, TRV023 failed to improve hemodynamics or survival compared to AngII, while losartan significantly improved survival. Both TRV023 and AngII enhanced proliferation and migration of pulmonary artery smooth muscle cells (PASMCs) from PAH patients, which was associated with the promotion of proliferative MAP kinase signaling.Conclusionsβ-arrestin-mediated AT1R signaling promotes vascular remodeling and worsens PAH, and suggests that the primary benefit of current PAH therapies is through pulmonary vascular reverse remodeling and not vasodilation.

Background: Extending the service scope of primary care facilities (PCFs) has been widely concerned in China. However, no current data about the association between service scope of PCFs with patient outcomes are available. This study aims to investigate the association between service scope of PCFs and patient outcomes. Methods: We first sampled four counties randomly from rural Guizhou, China. Claim data of 299,633 inpatient cases covered by 64 PCFs were derived from the local information system of New Rural Cooperation Medical Scheme. The service scope of PCFs was collected with self-administrated questionnaires. Primary outcomes were 1) level of inpatient institutions, 2) length of stay, 3) per capita total health cost, 4) per capita out-of-pocket cost, 5) reimbursement ratio, 6) 30-day readmission. A total of 64 PCFs were categorized into five groups per facility-level service scope scores. Generalized linear regression models, logistic regression model, and ordered regression model were conducted to identify the association between service scope of PCFs and patient outcomes. Results: On average, the median service scope score of PCFs was 20, with wide variation across PCFs. After controlling for demographic and clinical characteristics, patients living in communities with PCFs of greatest service scope (Quintile V vs. I) tended to have smaller rates of admission by county-level hospitals (-6.2% [-6.5%, -5.9%], city-level hospitals (-1.9% [-2.0%, -1.8%]), and provincial hospitals (-2.1% [-2.2%, -2.0%]), smaller rate of 30-day readmission (-0.5% [-0.7%, -0.3%]), less total health cost (-201.8 [-257.9, -145.8]) and out-of-pocket cost (-210.2 [-237.2, -183.2]), and greater reimbursement ratio (2.3% [1.9%, 2.8%]) than their counterparts from communities with PCFs of least service scope.Conclusion: The service scope of PCFs varied a lot in rural Guizhou, China. PCFs' greater service scope was associated with a reduction in secondary and tertiary hospital admission, reduced total cost and out-of-pocket cost, and 30-day readmission and increased reimbursement ratio. These results raised concerns about access to care for patients discharged from hospitals, which suggests potential opportunities for cost savings and improvement of quality of care. However, further evidence is warranted to investigate whether extending the service scope of PCFs is cost-effective and sustainable.

Another way for GPCRs to signal G protein–coupled receptors (GPCRs) normally transmit signals by coupling to heterotrimeric guanine nucleotide–binding proteins (G proteins) or by binding β-arrestin proteins. Smith et al. provide evidence for another mechanism, an approximate combination of the two. They monitored the interaction of vasopressin type 2 receptors (V2Rs) and G α proteins in cultured cells using bioluminescent resonance energy transfer. Even though V2Rs do not signal canonically through G α i proteins, they promoted the formation of complexes containing β-arrestin and G α i , and this led to downstream signaling to extracellular signal-regulated kinase protein kinases. Science , this issue p. eaay1833

Ulcerative colitis (UC) is an inflammatory bowel disease with complex pathogenesis, which is affected by genetic factors, intestinal immune status and intestinal microbial homeostasis. Intestinal epithelial barrier defect is crucial to the development of UC. Berberine, extracted from Chinese medicine, can identify bitter taste receptor on intestinal Tuft cells and activate IL-25-ILC2-IL-13 immune pathway to impair damaged intestinal tract by promoting differentiation of intestinal stem cells, which might be a potential approach for the treatment of UC.

The β 1 adrenergic receptor (β 1 AR) is a central regulator of cardiac function and an important therapeutic target for cardiac diseases. Two emerging areas of receptor biology are biased agonism: ligand directed selective engagement of a receptor toward either a G protein or β-arrestin transducer; and allosteric modulation: ligands that bind to topographically distinct sites on the receptor to modulate its activity. Advances in these areas have the potential to yield new drugs that precisely enhance cardioprotective effects while limiting untoward detrimental actions. Compound 6 (Cmpd6) is a newly discovered positive allosteric modulator (PAM) for the β 2 AR. Interestingly, we now show that Cmpd6 has the unique property to enhance the binding affinity of the β-arrestin-biased agonist carvedilol to both the β 2 AR and the β 1 AR, while having minimal effect on the affinity of a panel of agonists and antagonists of the β 1 AR. We further tested the effect of Cmpd6 on β 1 AR signaling induced by a broad range of ligands. Cmpd6 selectively enhanced carvedilol-stimulated ERK activation in a β-arrestin-dependent signaling fashion, while having no effect on carvedilol-induced G protein-dependent cAMP production. To test the in vivo effect of Cmpd6 on cardiac injury, mice were pretreated with carvedilol with or without Cmpd6, then underwent ischemia/reperfusion through the left anterior descending artery ligation. Cell apoptosis was assessed by TUNEL. Carvedilol decreased the level of I/R-induced apoptosis compared to the vehicle-treated animals, and Cmpd6 significantly positively enhanced the anti-apoptotic effects of carvedilol. In conclusion, we identified Cmpd6 as a potential β-arrestin-biased PAM for the β 1 AR that enhances the cardioprotective effect of carvedilol. Ongoing studies will test Cmpd6 on heart failure post myocardial infarction.

Hyperpolarized 129Xe magnetic resonance imaging (MRI) is capable of regional mapping of pulmonary gas-exchange and has found application in a wide range of pulmonary disorders in humans and animal model analogs. This study is the first application of 129Xe MRI to the monocrotaline rat model of pulmonary hypertension. Such models of preclinical pulmonary hypertension, a disease of the pulmonary vasculature that results in right heart failure and death, are usually assessed with invasive procedures such as right heart catheterization and histopathology. The work here adapted from protocols from clinical 129Xe MRI to enable preclinical imaging of rat models of pulmonary hypertension on a Bruker 7 T scanner. 129Xe spectroscopy and gas-exchange imaging showed reduced 129Xe uptake by red blood cells early in the progression of the disease, and at a later time point was accompanied by increased uptake by barrier tissues, edema, and ventilation defects—all of which are salient characteristics of the monocrotaline model. Imaging results were validated by H&E histology, which showed evidence of remodeling of arterioles. This proof-of-concept study has demonstrated that hyperpolarized 129Xe MRI has strong potential to be used to non-invasively monitor the progression of pulmonary hypertension in preclinical models and potentially to also assess response to therapy.

Hyperhomocysteinemia (HHcy) is an established and potent independent risk factor for degenerative diseases, including cardiovascular disease (CVD), Alzheimer disease, type II diabetes mellitus, and chronic kidney disease. HHcy has been shown to inhibit proliferation and promote inflammatory responses in endothelial cells (EC), and impair endothelial function, a hallmark for vascular injury. However, metabolic processes and molecular mechanisms mediating HHcy-induced endothelial injury remains to be elucidated. This study examined the effects of HHcy on the expression of microRNA (miRNA) and mRNA in human aortic EC treated with a pathophysiologically relevant concentration of homocysteine (Hcy 500 μM). We performed a set of extensive bioinformatics analyses to identify HHcy-altered metabolic and molecular processes. The global functional implications and molecular network were determined by Gene Set Enrichment Analysis (GSEA) followed by Cytoscape analysis. We identified 244 significantly differentially expressed (SDE) mRNA, their relevant functional pathways, and 45 SDE miRNA. HHcy-altered SDE inversely correlated miRNA-mRNA pairs (45 induced/14 reduced mRNA) were discovered and applied to network construction using an experimentally verified database. We established a hypothetical model to describe the biochemical and molecular network with these specified miRNA/mRNA axes, finding: 1) HHcy causes metabolic reprogramming by increasing glucose uptake and oxidation, by glycogen debranching and NAD+/CoA synthesis, and by stimulating mitochondrial reactive oxygen species production via NNT/IDH2 suppression-induced NAD+/NADP-NADPH/NADP+ metabolism disruption; 2) HHcy activates inflammatory responses by activating inflammasome-pyroptosis mainly through ↓miR193b→↑CASP-9 signaling and by inducing IL-1β and adhesion molecules through the ↓miR29c→↑NEDD9 and the ↓miR1256→↑ICAM-1 axes, as well as GPCR and interferon α/β signaling; 3) HHcy promotes cell degradation by the activation of lysosome autophagy and ubiquitin proteasome systems; 4) HHcy causes cell cycle arrest at G1/S and S/G2 transitions, suppresses spindle checkpoint complex and cytokinetic abscission, and suppresses proliferation through ↓miRNA335/↑VASH1 and other axes. These findings are in accordance with our previous studies and add a wealth of heretofore-unexplored molecular and metabolic mechanisms underlying HHcy-induced endothelial injury. This is the first study to consider the effects of HHcy on both global mRNA and miRNA expression changes for mechanism identification. Molecular axes and biochemical processes identified in this study are useful not only for the understanding of mechanisms underlying HHcy-induced endothelial injury, but also for discovering therapeutic targets for CVD in general., Graphical abstract Image 1, Highlights • Identified multiple HHcy-altered metabolic and molecular processes potentially responsible for HHcy-induced endothelial injury via examining global mRNA/miRNA expression changes in Hcy-treated EC and performing comprehensive bioinformatic studies. • HHcy may activate glucose uptake signaling via the ↓miR148b→↑SLC2A axis. • HHcy may induce glucose oxidation signaling by switching pyruvate metabolism from lactate synthesis to mitochondrial oxidation via expression changes of ↑MPC1 & ↓LDHB. • HHcy may disrupt redox homeostasis mostly by suppressing NNT/IDH2-related mt-NADPH/mt-NAD+ signaling. • HHcy may increase FA β-oxidation, glutamine, TCA cycle and OXPHOS signaling. • HHcy may activate inflammatory signaling via the ↓miR29c→↑NEDD9 and the ↓miR1256→↑ICAM-1 axes. • HHcy may activate inflammasome/pyroptosis-related signaling by the ↓miR137→↑TLR3, the ↓miR574→↑TRAF5, and the ↓miR193b→↑CASP-9 axes, and induce IL1α/β and CASP-10/7. • HHcy may induce inflammation signaling via GPCR activation through the ↓miRNA335→↑CXCR4/↑GNA14 axes. • HHcy may activate molecular degradation process signaling through the ↓miRNA335→↑ASAH1/↑ABCB9 axes. • HHcy may suppress cell cycle and proliferation through the miR491→↓HMGA2→↓CCNA2/CCNB2, the ↓miR335→↑VASH1, the ↓miR181a→↑PHLDA1, the miR6045→↓CENPH, the miR22→↓PRR11/↓BRCA2, and the miR605/miR497/miR514a→CEP55 axes