Validation of ferroptosis in canine cancer cells to enable comparative oncology and translational medicine

Ferroptosis is a cell death mechanism that has attracted significant attention as a potential basis for the development of new cancer therapies. Validation of ferroptosis biology in species commonly used in translation and pre-clinical development is a necessary foundation for enabling the advancement of such ferroptosis modulating drugs. Here, we demonstrate that canine cancer cells exhibit sensitivity to a wide range of ferroptosis-inducing perturbations in a manner indistinguishable from human cancer cells, and recapitulate characteristic patterns of ferroptotic response across tumor types seen in the human setting. The foundation provided herein establishes the dog as a relevant efficacy and toxicology model for ferroptosis and creates new opportunities to leverage the canine comparative oncology paradigm to accelerate the development of ferroptosis-inducing drugs for human cancer patients.

Discovery and Identification of Novel 5-Hydroxy-4H-benzo[1,4]oxazin-3-one Derivatives as Potent β2-Adrenoceptor Agonists through Structure-Based Design, Synthesis, and Biological Evaluation

Although β2-agonists are crucial for treatment of chronic respiratory diseases, optimizing β2-agonistic activity and selectivity remains essential for achieving favorable therapeutic outcomes. A structure-based molecular design workflow was employed to discover a novel class of β2 agonists featuring a 5-hydroxy-4H-benzo[1,4]oxazin-3-one scaffold, which potently stimulated β2 adrenoceptors (β2-ARs). Screening for the β2-agonistic activity and selectivity led to the identification of compound A19 (EC50 = 3.7 pM), which functioned as a partial β2-agonist in HEK-293 cells containing endogenous β2-ARs. Compound A19 exhibited significant relaxant effects, rapid onset time (Ot50 = 2.14 min), and long duration of action (>12 h) on isolated guinea pig tracheal strips, as well as advantageous pharmacokinetic characteristics in vivo, rendering A19 suitable for inhalation administration. Moreover, A19 suppressed the upregulation of inflammatory cytokines and leukocytes and improved lung function in a rat model of COPD, thereby indicating that A19 is a potential β2 agonist candidate for further study.

Evaluation of microbial communities of Chinese Feng-flavor Daqu with effects of environmental factors using traceability analysis

Analysis of the changes of microorganisms during Chinese Feng-flavor Daqu fermentation, and the specific contribution of different environmental factors to Daqu microorganisms. High throughput sequencing technology and SourceTracker software were used to analyze the microbial diversity of Feng-flavor Daqu before and after fermentation. 85 fungal and 105 bacterial were detected in the newly pressed Feng-flavor Daqu, while 33 fungal and 50 bacterial in the mature Daqu, and 202 fungal and 555 bacterial in the environmental samples. After fermentation, the microbial community structure of Daqu changed and decreased significantly. 94.7% of fungi come from raw materials and 1.8% from outdoor ground, 60.95% of bacteria come from indoor ground, 20.44% from raw materials, and 8.98% from tools. By comparing the changes of microorganisms in Daqu before and after fermentation, the microorganisms in mature Daqu may mainly come from not only the enhanced strains but also the environment.The source of main microorganisms in Feng-flavor Daqu and the influence of environmental factors on the quality of Daqu were clarified, which provided a basis for improving the quality of Feng-flavor Daqu.

AV-casNet: Fully Automatic Arteriole-Venule Segmentation and Differentiation in OCT Angiography

Automatic segmentation and differentiation of retinal arteriole and venule (AV), defined as small blood vessels directly before and after the capillary plexus, are of great importance for the diagnosis of various eye diseases and systemic diseases, such as diabetic retinopathy, hypertension, and cardiovascular diseases. Optical coherence tomography angiography (OCTA) is a recent imaging modality that provides capillary-level blood flow information. However, OCTA does not have the colorimetric and geometric differences between AV as the fundus photography does. Various methods have been proposed to differentiate AV in OCTA, which typically needs the guidance of other imaging modalities. In this study, we propose a cascaded neural network to automatically segment and differentiate AV solely based on OCTA. A convolutional neural network (CNN) module is first applied to generate an initial segmentation, followed by a graph neural network (GNN) to improve the connectivity of the initial segmentation. Various CNN and GNN architectures are employed and compared. The proposed method is evaluated on multi-center clinical datasets, including 3 ×3 mm2 and 6 ×6 mm2 OCTA. The proposed method holds the potential to enrich OCTA image information for the diagnosis of various diseases.

BDK inhibition acts as a catabolic switch to mimic fasting and improve metabolism in mice

OBJECTIVE

Branched chain amino acid (BCAA) catabolic defects are implicated to be causal determinates of multiple diseases. This work aimed to better understand how enhancing BCAA catabolism affected metabolic homeostasis as well as the mechanisms underlying these improvements.

METHODS

The rate limiting step of BCAA catabolism is the irreversible decarboxylation by the branched chain ketoacid dehydrogenase (BCKDH) enzyme complex, which is post-translationally controlled through phosphorylation by BCKDH kinase (BDK). This study utilized BT2, a small molecule allosteric inhibitor of BDK, in multiple mouse models of metabolic dysfunction and NAFLD including the high fat diet (HFD) model with acute and chronic treatment paradigms, the choline deficient and methionine minimal high fat diet (CDAHFD) model, and the low-density lipoprotein receptor null mouse model (Ldlr^-/-). shRNA was additionally used to knock down BDK in liver to elucidate liver-specific effects of BDK inhibition in HFD-fed mice.

RESULTS

A rapid improvement in insulin sensitivity was observed in HFD-fed and lean mice after BT2 treatment. Resistance to steatosis was assessed in HFD-fed mice, CDAHFD-fed mice, and Ldlr^-/- mice. In all cases, BT2 treatment reduced steatosis and/or inflammation. Fasting and refeeding demonstrated a lack of response to feeding-induced changes in plasma metabolites including insulin and beta-hydroxybutyrate and hepatic gene changes in BT2-treated mice. Mechanistically, BT2 treatment acutely altered the expression of genes involved in fatty acid oxidation and lipogenesis in liver, and upstream regulator analysis suggested that BT2 treatment activated PPARα. However, BT2 did not directly activate PPARα in vitro. Conversely, shRNA-AAV-mediated knockdown of BDK specifically in liver in vivo did not demonstrate any effects on glycemia, steatosis, or PPARα-mediated gene expression in mice.

CONCLUSIONS

These data suggest that BT2 treatment acutely improves metabolism and liver steatosis in multiple mouse models. While many molecular changes occur in liver in BT2-treated mice, these changes were not observed in mice with AAV-mediated shRNA knockdown of BDK. All together, these data suggest that systemic BDK inhibition is required to improve metabolism and steatosis by prolonging a fasting signature in a paracrine manner. Therefore, BCAA may act as a "fed signal" to promote nutrient storage and reduced systemic BCAA levels as shown in this study via BDK inhibition may act as a "fasting signal" to prolong the catabolic state.

Improving the Air Resistance of the Precursor Solution for Ambient-Air Coating of an Sn-Pb Perovskite Film with Superior Photovoltaic Performance

Owing to narrow band gap and low toxicity, tin-lead (Sn-Pb) hybrid perovskites have shown great potential in photovoltaic applications, and the highest power conversion efficiency (PCE) of Sn-Pb perovskite solar cells (PSCs) has recently reached 23.6%. However, it is still challenging to prepare Sn-Pb films in open-air condition due to the Sn²⁺ oxidation of the precursor solution under this condition. In this work, we report the stabilizing of the Sn-Pb perovskite precursor solution by using ionic liquid methylammonium acetate (MAAc) as the solvent, which enables the fabrication of Sn-Pb films in air. MAAc is found to coordinate with the Sn-Pb precursor via abundant hydrogen bonding, which stabilizes the colloids and protects the Sn²⁺ stability in the precursor solution in air. Therefore, the durability of the Sn-Pb precursor solution based on the MAAc solvent is greatly improved, which enables the fabrication of efficient PSCs and achieves a champion PCE of ∼16% with robust device stability. Moreover, due to the chemical interactions of MAAc with Sn-Pb perovskites, the Pb leakage is also suppressed in the MAAc-based Sn-Pb PSCs. This work demonstrates a feasible strategy for reliable fabrication of Sn-Pb PSCs, which could also be applied in many other optoelectronic devices.

Drug-loaded PEG-PLGA nanoparticles for cancer treatment

Nanoparticles based on single-component synthetic polymers, such as poly (lactic acid-co-glycolic acid) (PLGA), have been extensively studied for antitumor drug delivery and adjuvant therapy due to their ability to encapsulate and release drugs, as well as passively target tumors. Amphiphilic block co-polymers, such as polyethylene glycol (PEG)-PLGA, have also been used to prepare multifunctional nanodrug delivery systems with prolonged circulation time and greater bioavailability that can encapsulate a wider variety of drugs, including small molecules, gene-targeting drugs, traditional Chinese medicine (TCM) and multi-target enzyme inhibitors, enhancing their antitumor effect and safety. In addition, the surface of PEG-PLGA nanoparticles has been modified with various ligands to achieve active targeting and selective accumulation of antitumor drugs in tumor cells. Modification with two ligands has also been applied with good antitumor effects, while the use of imaging agents and pH-responsive or magnetic materials has paved the way for the application of such nanoparticles in clinical diagnosis. In this work, we provide an overview of the synthesis and application of PEG-PLGA nanoparticles in cancer treatment and we discuss the recent advances in ligand modification for active tumor targeting.

The Inactivated gE/TK Gene-Deleted Vaccine Against Pseudorabies Virus Type II Confers Effective Protection in Mice and Pigs

The highly virulent and antigenic variant of Pseudorabies virus (PRV) that emerged from classical Bartha-K61-vaccinated pig herds has caused substantial economic losses to the swine industry in China since 2011. A safe and more effective vaccine is most desirable. In this study, a gE/TK gene-deficient PRV, namely, HD/c, was constructed based on a PRV type II DX strain isolated from a commercial vaccine-immunized farm and the HD/c-based inactivated vaccine was formulated and evaluated for its safety, immunogenicity, and protective efficacy in mice and piglets. The resulting PRV HD/c strain has a similar growth curve to the parental DX strain. After vaccination, the inactivated HD/c vaccine did not cause any visible gross pathological or histopathological changes in the tissues of mice and piglets and provided rapid and potent protection against the challenge of the classical and variant PRVs at day 21 post-vaccination in mice. A single immunization of 10^8.5TCID₅₀ inactivated PRV HD/c strain-elicited robust immunity with high titer of neutralizing antibody and provided complete protection from the lethal challenge of PRV DX strain in piglets. These results indicated that the inactivated PRV HD/c vaccine with the deletion of gE/TK genes was a safe and effective PRV vaccine candidate for the control of PRV.

Identification of Metoprolol Tartrate-Derived Reactive Metabolites Possibly Correlated with Its Cytotoxicity

As a selective β₁-receptor antagonist, metoprolol tartrate (MTA) is commonly used to treat cardiovascular diseases such as hypertension and angina pectoris. There have been cases of liver injury induced by MTA, but the mechanism of hepatotoxicity induced by MTA is not clear. The purposes of this study were to identify the reactive metabolites of MTA, to determine the pathway for the metabolic activation of MTA, and to define a possible correlation between the metabolic activation and cytotoxicity of MTA. Three oxidative metabolites (M1-M3), a glutathione (GSH) conjugate (M4), and an N-acetyl cysteine (NAC) conjugate (M5) were detected in rat liver microsomal incubations containing MTA and GSH or NAC. M4 was also detected in cultured rat primary hepatocytes and bile of rats given MTA, and M5 was detected in the urine of MTA-treated rats. A quinone methide intermediate may be produced from the metabolic activation process in vitro and in vivo. The metabolite was reactive to glutathione and N-acetyl cysteine. MTA induced marked cytotoxicity in cultured rat primary hepatocytes. Pretreatment of aminobenzotriazole, a nonselective P450 enzyme inhibitor, attenuated the susceptibility of hepatocytes to MTA cytotoxicity.

Multi-Scale Pathological Fluid Segmentation in OCT With a Novel Curvature Loss in Convolutional Neural Network

The segmentation of pathological fluid lesions in optical coherence tomography (OCT), including intraretinal fluid, subretinal fluid, and pigment epithelial detachment, is of great importance for the diagnosis and treatment of various eye diseases such as neovascular age-related macular degeneration and diabetic macular edema. Although significant progress has been achieved with the rapid development of fully convolutional neural networks (FCN) in recent years, some important issues remain unsolved. First, pathological fluid lesions in OCT show large variations in location, size, and shape, imposing challenges on the design of FCN architecture. Second, fluid lesions should be continuous regions without holes inside. But the current architectures lack the capability to preserve the shape prior information. In this study, we introduce an FCN architecture for the simultaneous segmentation of three types of pathological fluid lesions in OCT. First, attention gate and spatial pyramid pooling modules are employed to improve the ability of the network to extract multi-scale objects. Then, we introduce a novel curvature regularization term in the loss function to incorporate shape prior information. The proposed method was extensively evaluated on public and clinical datasets with significantly improved performance compared with the state-of-the-art methods.

Discovery of a Highly Selective β2-Adrenoceptor Agonist with a 2-Amino-2-phenylethanol Scaffold as an Oral Antiasthmatic Agent

Asthma patients in resource-poor countries cannot obtain adequate basic asthma medications because most asthma medications are supplied as inhalants. An alternative approach is to create oral antiasthmatic drugs with high β₂/β₁-selectivity, which should reduce treatment costs. In this study, we designed a cohort of compounds 1 using 2-(4-amino-3-chloro-5-(trifluoromethyl)phenyl)-2-(tert-butylamino)ethan-1-ol hydrogen chloride (1a) as the lead compound with an aim to expand the library of compounds possessing the 2-amino-2-phenylethanol scaffold. Structure-activity relationship studies on these compounds revealed that compounds created showed remarkable β₂ selectivity compared to isoproterenol and gave additional insights on the rational design of β₂-adrenoceptor agonists. Moreover, 1a was found as the best candidate compound showing the greatest potential for drug development. Cell-based assays showed that 1a was about 10 times more selective than salbutamol toward the β₂-adrenoceptor. Moreover, 1a exhibited good oral bioavailability and low acute oral toxicity. These data reveal 1a as an oral antiasthmatic agent.

Virome characterization of game animals in China reveals a spectrum of emerging pathogens

Game animals are wildlife species traded and consumed as food and are potential reservoirs for SARS-CoV and SARS-CoV-2. We performed a meta-transcriptomic analysis of 1,941 game animals, representing 18 species and five mammalian orders, sampled across China. From this, we identified 102 mammalian-infecting viruses, with 65 described for the first time. Twenty-one viruses were considered as potentially high risk to humans and domestic animals. Civets (Paguma larvata) carried the highest number of potentially high-risk viruses. We inferred the transmission of bat-associated coronavirus from bats to civets, as well as cross-species jumps of coronaviruses from bats to hedgehogs, from birds to porcupines, and from dogs to raccoon dogs. Of note, we identified avian Influenza A virus H9N2 in civets and Asian badgers, with the latter displaying respiratory symptoms, as well as cases of likely human-to-wildlife virus transmission. These data highlight the importance of game animals as potential drivers of disease emergence.

Development and validation of a HILIC-MS/MS method for the quantitation of fructose in human urine in support of clinical programs

In a previous publication [1], a 20-minute UPLC®-MS/MS method, employing a surrogate analyte approach, was developed and validated to measure fructose and sorbitol, as mechanistic biomarkers, in human plasma to support first-in-human (FIH) studies. Different from plasma which maintains its homeostasis, urine has no such homeostasis mechanisms [2], therefore it is expected to be able to accommodate more changes. Here we describe the development and validation of a LC-MS/MS method for the quantiation of fructose in human urine to support clinical trials. A hydrophilic interaction chromatography (HILIC) method using an Asahipak NH2P-50 column (Shodex, 4.6 × 250 mm, 5 µm) was developed. Acetone precipitation was utilized to extract fructose from urine. For validation, stable isotope-labeled ¹³C₆-fructose was used as the surrogate analyte for fructose in the preparation of calibration curves. QCs were prepared using both the surrogate analyte (¹³C₆-fructose) and the authentic analyte (fructose). Difficulties were encountered for post-extraction stability experiments especially for authentic fructose QCs at low concentrations. Extensive troubleshooting revealed that fructose's chromatography improved as the column aged. As a result, the response factor of fructose increased over time for low concentration samples, leading to failed post-extraction stability experiments. A column cleaning procedure was implemented to ensure consistency in chromatography performance. The HILIC-MS/MS method was successfully validated and applied to analyze clinical samples with a 91% overall run passing rate.

lncRNA MIR4435‑2HG promotes the progression of liver cancer by upregulating B3GNT5 expression

Several studies have indicated that dysregulation of long non-coding RNAs (lncRNAs) participates in the initiation and progression of cancer. The lncRNA MIR4435-2HG was previously reported to act as an oncogene in human cancer, including liver cancer. However, its role in the pathogenesis in liver cancer is largely unclear. The present study aimed to reveal the molecular mechanism by which MIR4435-2HG regulates liver cancer. The expression levels of MIR4435-2HG in liver cancer and adjacent normal tissues were analyzed using The Cancer Genome Atlas database. MIR4435-2HG expression was validated by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in cancer cells in vitro. The target genes of MIR4435-2HG were predicted using bioinformatics analysis. Interactions between miR-136-5p, MIR4435-2HG and B3GNT5 were detected using luciferase reporter assays, and their effects on cell viability, migration and invasion were assessed using Cell Counting Kit-8, wound healing and Transwell assays. The effects of miR-136-5p and MIR4435-2HG on B3GNT5 expression were confirmed by western blot analysis. The results revealed that MIR4435-2HG expression was upregulated in primary liver cancer and liver cancer cell lines, and was positively associated with advanced tumor stage, metastasis and poor prognosis in patients with liver cancer. Knockdown of MIR4435-2HG significantly inhibited the proliferation, migration and invasion of liver cancer cells. Furthermore, miR-136-5p was determined to be a direct target of MIR4435-2HG and suppressed MIR4435-2HG expression by binding with the seed region of the 3′-UTR of MIR4435-2HG in liver cancer cells. Functional studies showed that the inhibitory effects of MIR4435-2HG knockdown on cell proliferation, migration and invasion were significantly rescued by inhibiting miR-136-5p. Furthermore, the target gene, B3GNT5, of miR-136-5p was confirmed by bioinformatics analysis and RT-qPCR. In addition, B3GNT5 expression was regulated by the MIR4435-2HG/miR-136-5p axis. In conclusion, the present study indicated that MIR4435-2HG facilitated the progression of liver cancer via the MIR4435-2HG/miR-136-5p/B3GNT5 axis, which demonstrated that MIR4435-2HG may be a potential biomarker for the prognosis and treatment of liver cancer.

Serine catabolism generates liver NADPH and supports hepatic lipogenesis

Carbohydrate can be converted into fat by de novo lipogenesis, a process upregulated in fatty liver disease. Chemically, de novo lipogenesis involves polymerization and reduction of acetyl-CoA, using NADPH as the electron donor. The feedstocks used to generate acetyl-CoA and NADPH in lipogenic tissues remain, however, unclear. Here we show using stable isotope tracing in mice that de novo lipogenesis in adipose is supported by glucose and its catabolism via the pentose phosphate pathway to make NADPH. The liver, in contrast, derives acetyl-CoA for lipogenesis from acetate and lactate, and NADPH from folate-mediated serine catabolism. Such NADPH generation involves the cytosolic serine pathway in liver running in the opposite direction to that observed in most tissues and tumours, with NADPH made by the SHMT1-MTHFD1-ALDH1L1 reaction sequence. SHMT inhibition decreases hepatic lipogenesis. Thus, liver folate metabolism is distinctively wired to support cytosolic NADPH production and lipogenesis. More generally, while the same enzymes are involved in fat synthesis in liver and adipose, different substrates are used, opening the door to tissue-specific pharmacological interventions.

Untargeted lipidomics analysis in women with intrahepatic cholestasis of pregnancy: a cross-sectional study

OBJECTIVE

To compare the plasma lipid profiles in women with normal pregnancies and those with mild or severe intrahepatic cholestasis of pregnancy (ICP). Our goal was to reveal lipidome-wide alterations in ICP and delve into the pathogenesis of ICP from a lipid metabolism perspective.

DESIGN

Cross-sectional study, including women with normal pregnancies, women with mild ICP and women with severe ICP.

SETTING

Gansu Provincial Hospital.

POPULATION

Women with ICP were recruited from October 2019 to March 2020 in Gansu, China.

METHODS

Untargeted lipidomics was used to analyse differentially expressed plasma lipids in controls, in women with mild ICP and in women with severe ICP (n = 30 per group). For lipidomics, liquid chromatography and Q-Exactive Plus Orbitrap mass spectrometry were performed.

MAIN OUTCOME MEASURES

Differentially expressed lipids.

RESULTS

Thirty-three lipids were differentially expressed in the severe and mild ICP groups, compared with the control group, and 20 of those were sphingolipids (ceramide, six species; sphingomyelin, 14 species). All differentially expressed sphingolipids in women with mild ICP were also differentially expressed in women with severe ICP; the fold change and significance of the differential expression were positively correlated with disease severity.

CONCLUSIONS

We systematically characterized the lipidome-wide alterations in mild and severe ICP groups. The results indicated a link between ICP and disordered sphingolipid homeostasis.

TWEETABLE ABSTRACT

Abnormal sphingolipid metabolism is involved in the pathogenesis of ICP.

Knockdown of long noncoding RNA colorectal neoplasia differentially expressed inhibits hepatocellular carcinoma progression by mediating the expression of nuclear autoantigenic sperm protein

Long noncoding RNAs (lncRNAs) play critical roles in the tumorigenesis and progression of hepatocellular carcinoma (HCC). As the most common malignant cancer type in humans, HCC poses a great threat to human health. However, the function of lncRNA colorectal neoplasia differentially expressed (CRNDE) in HCC has not been extensively studied. The chief aim of the present study was to reveal the potential role of CRNDE in HCC. Expression levels of CRNDE in HCC tissues and cell lines were detected by reverse transcription‑quantitative (RT‑q) PCR, and Cell Counting kit 8, wound‑healing and Transwell assays were used to evaluate the influences of CRNDE on in vitro cellular proliferation, migration and invasiveness, respectively. The interaction between CRNDE and microRNA (miR)‑29c‑3p was determined by dual‑luciferase reporter assay, and rescue experiments were conducted to evaluate the interactive relationships between CRNDE and miR‑29c‑3p or nuclear autoantigenic sperm protein (NASP). CRNDE was found to be upregulated in HCC tissues and cells, and to be positively associated with the poor prognosis of patients with HCC. Furthermore, CRNDE‑knockdown suppressed cell proliferation, migration and invasion abilities. Bioinformatics and RT‑qPCR analysis indicated miR‑29c‑3p as a potential target of CRNDE. In line with previous reports, as a tumor suppressor, downregulated expression of miR‑29c‑3p was observed in HCC. In addition, the present study revealed that miR‑29c‑3p directly targeted NASP. NASP expression was markedly elevated following transfection with an miR‑29c‑3p inhibitor, while knocking down CRNDE inhibited NASP expression. Moreover, the effects of CRNDE and NASP on HCC cells were reversed by miR‑29c‑3p. Collectively, the results of the present study revealed that CRNDE was upregulated and exerted an oncogenic role in HCC by targeting miR‑29c‑3p, and that the upregulation of CRNDE also promoted NASP expression. These findings indicate a novel role for CRNDE in the progression of HCC.

Emergence and adaptive evolution of influenza D virus

As a novel member of the Orthomyxoviridae, influenza D virus (IDV) was firstly isolated from swine. However, cattle were found to serve as its primary reservoir. The study of IDV emergence can shed light into the dynamics of zoonotic infections and interspecies transmission. Although there is an increasing number of strains and sequenced IDV strains, their origin, epidemiology and evolutionary dynamics remain unclear. In this study, we reconstruct the diversity and evolutionary dynamics of IDVs. Molecular detection of swine tissue samples shows that six IDV positive samples were identified in the Eastern China. Phylogenetic analyses suggest three major IDV lineages designated as D/Japan, D/OK and D/660 as well as intermediate lineages. IDVs show strong association with geographical location indicating a high level of local transmission, which suggests IDVs tend to establish a local lineage of in situ evolution. In addition, the D/OK lineage widely circulates in swine in Eastern China, and all of the Chinese virus isolates form a distinct sub-clade (D/China sub-lineage). Furthermore, we identified important amino acids in the HEF gene under positive selection that might affect its receptor binding cavity relevant for its broader cell tropism. The combined results highlight that more attention should be paid to the potential threat of IDV to livestock and farming in China.

The emerging landscape of long non-coding RNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common and aggressive cancers. HCC shows high prevalence and lethality caused by a variety of etiologic factors. However, the underlying mechanisms and the diagnostic markers identifying patients at risk in advance has not been entirely elucidated. Long non-coding RNAs (lncRNAs) are a subgroup of non-coding RNAs greater than 200 nucleotides in length with no protein-coding capability. With the progress in sequencing technologies and bioinformatic tools, the landscape of lncRNAs is being revealed. Numerous discoveries point out that lncRNAs participate in HCC carcinogenesis and metastasis through altering cell proliferation and invasion ability, apoptosis, and chemo- or radio-sensitivity. Moreover, lncRNA is easy to detect compared to the traditional diagnostic methods. This review summarizes the mechanisms of major lncRNAs in HCC discovered in recent years and lncRNAs as early diagnostic markers for HCC.

8-Hydroxyquinolin-2(1H)-one analogues as potential β2-agonists: Design, synthesis and activity study

β₂-Agonists that bind to plasmalemmal β₂-adrenoceptors causing cAMP accumulation are widely used as bronchodilators in chronic respiratory diseases. Here, we designed and synthesized a group of 8-hydroxyquinolin-2(1H)-one analogues and studied their β₂-agonistic activities with a cellular cAMP assay. Compounds B05 and C08 were identified as potent (EC₅₀ < 20 pM) and selective β₂-agonists among the compounds tested. They behaved as partial β₂-agonists in non-overexpressed HEK293 cells, and possessed rapid smooth muscle relaxant actions and long duration of action in isolated guinea pig tracheal strip preparations. In summary, B05 and C08 are β₂-agonists with potential applicability in chronic respiratory diseases.

Pharmacologic inhibition of ketohexokinase prevents fructose-induced metabolic dysfunction

Objective

Recent studies suggest that excess dietary fructose contributes to metabolic dysfunction by promoting insulin resistance, de novo lipogenesis (DNL), and hepatic steatosis, thereby increasing the risk of obesity, type 2 diabetes (T2D), non-alcoholic steatohepatitis (NASH), and related comorbidities. Whether this metabolic dysfunction is driven by the excess dietary calories contained in fructose or whether fructose catabolism itself is uniquely pathogenic remains controversial. We sought to test whether a small molecule inhibitor of the primary fructose metabolizing enzyme ketohexokinase (KHK) can ameliorate the metabolic effects of fructose.

Methods

The KHK inhibitor PF-06835919 was used to block fructose metabolism in primary hepatocytes and Sprague Dawley rats fed either a high-fructose diet (30% fructose kcal/g) or a diet reflecting the average macronutrient dietary content of an American diet (AD) (7.5% fructose kcal/g). The effects of fructose consumption and KHK inhibition on hepatic steatosis, insulin resistance, and hyperlipidemia were evaluated, along with the activation of DNL and the enzymes that regulate lipid synthesis. A metabolomic analysis was performed to confirm KHK inhibition and understand metabolite changes in response to fructose metabolism in vitro and in vivo. Additionally, the effects of administering a single ascending dose of PF-06835919 on fructose metabolism markers in healthy human study participants were assessed in a randomized placebo-controlled phase 1 study.

Results

Inhibition of KHK in rats prevented hyperinsulinemia and hypertriglyceridemia from fructose feeding. Supraphysiologic levels of dietary fructose were not necessary to cause metabolic dysfunction as rats fed the American diet developed hyperinsulinemia, hypertriglyceridemia, and hepatic steatosis, which were all reversed by KHK inhibition. Reversal of the metabolic effects of fructose coincided with reductions in DNL and inactivation of the lipogenic transcription factor carbohydrate response element-binding protein (ChREBP). We report that administering single oral doses of PF-06835919 was safe and well tolerated in healthy study participants and dose-dependently increased plasma fructose indicative of KHK inhibition.

Conclusions

Fructose consumption in rats promoted features of metabolic dysfunction seen in metabolic diseases such as T2D and NASH, including insulin resistance, hypertriglyceridemia, and hepatic steatosis, which were reversed by KHK inhibition.

•

PF-06835919 is a potent inhibitor of fructose metabolism in rats and humans.

•

Rats fed fructose at levels consistent with the typical American diet develop hyperinsulinemia, hyperlipidemia and steatosis.

•

KHK inhibition reverses fructose-induced metabolic dysfunction by blocking ChREBP activation.

•

Due to the global dietary prevalence of fructose, KHK inhibition is a potential pharmacotherapy for metabolic diseases.

Recent progress in the development of β2 adrenergic receptor agonists: a patent review (2015-2020)

INTRODUCTION

The β₂ adrenergic receptor (β₂AR) is a member of G protein-coupled receptors (GPCRs) that mediate the majority of cellular responses to external stimuli. The agonists can cause smooth muscle relaxation; therefore, many β₂AR agonists have been developed especially for the treatment of pulmonary disorders such as asthma and chronic obstructive pulmonary disease (COPD). Many new natural and synthetic compounds have been discovered and developed as novel β₂AR agonists over the past 5 years.

AREAS COVERED

This review offers an update for the development of β₂AR agonists in the patents published from 2015 to 2020, including new natural and synthetic compounds for the treatment of asthma and COPD. In particular, the latest patents about compounds possessing both muscarinic receptor antagonist and β₂ adrenergic receptor agonist activity are reviewed.

EXPERT OPINION

β₂AR agonists have been developed extensively for the treatment of asthma and COPD. In the past 5 years, novel agonists from both natural sources and synthetic methods were intensively developed. Compounds possessing both muscarinic receptor antagonist and β₂AR agonist activity represent a new trend in this area because they are possibly able to act together in a synergistic fashion, therefore, relieve the symptoms of patients through two distinct mechanisms.

Recent Advances in β2-Agonists for Treatment of Chronic Respiratory Diseases and Heart Failure

β₂-Adrenoceptor (β₂-AR) agonists are widely used as bronchodilators. The emerge of ultralong acting β₂-agonists is an important breakthrough in pulmonary medicine. In this review, we will provide mechanistic insights into the application of β₂-agonists in asthma, chronic obstructive pulmonary disease (COPD), and heart failure (HF). Recent studies in β-AR signal transduction have revealed opposing functions of the β₁-AR and the β₂-AR on cardiomyocyte survival. Thus, β₂-agonists and β-blockers in combination may represent a novel strategy for HF management. Allosteric modulation and biased agonism at the β₂-AR also provide a theoretical basis for developing drugs with novel mechanisms of action and pharmacological profiles. Overlap of COPD and HF presents a substantial clinical challenge but also a unique opportunity for evaluation of the cardiovascular safety of β₂-agonists. Further basic and clinical research along these lines can help us develop better drugs and innovative strategies for the management of these difficult-to-treat diseases.

Discovery of PF-06835919: A Potent Inhibitor of Ketohexokinase (KHK) for the Treatment of Metabolic Disorders Driven by the Overconsumption of Fructose

Increased fructose consumption and its subsequent metabolism have been implicated in metabolic disorders such as nonalcoholic fatty liver disease and steatohepatitis (NAFLD/NASH) and insulin resistance. Ketohexokinase (KHK) converts fructose to fructose-1-phosphate (F1P) in the first step of the metabolic cascade. Herein we report the discovery of a first-in-class KHK inhibitor, PF-06835919 (8), currently in phase 2 clinical trials. The discovery of 8 was built upon our originally reported, fragment-derived lead 1 and the recognition of an alternative, rotated binding mode upon changing the ribose-pocket binding moiety from a pyrrolidinyl to an azetidinyl ring system. This new binding mode enabled efficient exploration of the vector directed at the Arg-108 residue, leading to the identification of highly potent 3-azabicyclo[3.1.0]hexane acetic acid-based KHK inhibitors by combined use of parallel medicinal chemistry and structure-based drug design.

Genomic Epidemiology, Evolution, and Transmission Dynamics of Porcine Deltacoronavirus

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has shown once again that coronavirus (CoV) in animals are potential sources for epidemics in humans. Porcine deltacoronavirus (PDCoV) is an emerging enteropathogen of swine with a worldwide distribution. Here, we implemented and described an approach to analyze the epidemiology of PDCoV following its emergence in the pig population. We performed an integrated analysis of full genome sequence data from 21 newly sequenced viruses, along with comprehensive epidemiological surveillance data collected globally over the last 15 years. We found four distinct phylogenetic lineages of PDCoV, which differ in their geographic circulation patterns. Interestingly, we identified more frequent intra- and interlineage recombination and higher virus genetic diversity in the Chinese lineages compared with the USA lineage where pigs are raised in different farming systems and ecological environments. Most recombination breakpoints are located in the ORF1ab gene rather than in genes encoding structural proteins. We also identified five amino acids under positive selection in the spike protein suggesting a role for adaptive evolution. According to structural mapping, three positively selected sites are located in the N-terminal domain of the S1 subunit, which is the most likely involved in binding to a carbohydrate receptor, whereas the other two are located in or near the fusion peptide of the S2 subunit and thus might affect membrane fusion. Finally, our phylogeographic investigations highlighted notable South-North transmission as well as frequent long-distance dispersal events in China that could implicate human-mediated transmission. Our findings provide new insights into the evolution and dispersal of PDCoV that contribute to our understanding of the critical factors involved in CoVs emergence.

Etiology and genetic evolution of canine coronavirus circulating in five provinces of China, during 2018-2019

As the outbreaks of COVID-19 in worldwide, coronavirus has once again caught the attention of people. Canine coronavirus is widespread among dog population, and sometimes causes even fatal cases. Here, to characterize the prevalence and evolution of current circulating canine coronavirus (CCoV) strains in China, we collected 213 fecal samples from diarrheic pet dogs between 2018 and 2019. Of the 213 samples, we found 51 (23.94%) were positive for CCoV. Co-infection with canine parvovirus (CPV), canine astrovirus (CaAstV), canine kobuvirus (CaKV), Torque teno canis virus (TTCaV) were ubiquitous existed. Mixed infection of different CCoV subtypes exists extensively. Considering the limited sequences data in recent years, we sequenced 7 nearly complete genomes and 10 complete spike gene. Phylogenetic analysis of spike gene revealed a new subtype CCoV-II Variant and CCoV-IIa was the most prevalent subtype currently circulating. Moreover, we identified strain B906_ZJ_2019 shared 93.24% nucleotide identifies with previous strain A76, and both of them clustered with CCoV-II Variant, which were not well clustered with the known subtypes. Recombination analysis of B906_ZJ_2019 indicated that strain B906_ZJ_2019 may a recombinant variant between CCoV–I and CCoV-II, which is consistent with strain A76. Furthermore, amino acid variations widely existed among current CCoV-IIa strains circulating in China and the classic CCoV-IIa strains, in spite of the unknown functions.

In a word, we report a useful information as to the etiology and evolution of canine coronavirus in China based on the available sequences, which is urgent for the devise of future effective disease prevention and control strategies.

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Phylogenetic analysis revealed a new subtype CCoV-II Variant and currently the most prevalent subtype CCoV-IIa.

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Strain B906_ZJ_2019 shared 93.24% nucleotide identify with strain A76, and both of them clustered with CCoV-II Variant.

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Amino acid variations widely existed among current CCoV-IIa strains circulating in China and the classic CCoV-IIa strains.

Interspecies Transmission, Genetic Diversity, and Evolutionary Dynamics of Pseudorabies Virus

BACKGROUND

Pseudorabies virus (PRV) causes Aujeszky's disease in pigs and can be transmitted to other mammals, including humans. In the current study, we systematically studied the interspecies transmission and evolutionary history of PRV.

METHODS

We performed comprehensive analysis on the phylodynamics, selection, and structural biology to summarize the phylogenetic and adaptive evolution of PRV based on all available full-length and major glycoprotein sequences.

RESULTS

PRV can be divided into 2 main clades with frequent interclade and intraclade recombination. Clade 2.2 (variant PRV) is currently the most prevalent genotype worldwide, and most commonly involved in cross-species transmission events (including humans). We also found that the population size of clade 2.2 has increased since 2011, and the effective reproduction number was >1 from 2011 to 2016, indicating that PRV may be still circulating in swine herds and is still a risk in relation with cross-species transmission in China. Of note, we identified amino acid sites in some important glycoproteins gB, gC, gD, and gE that may be associated with PRV adaptation to new hosts and immune escape to vaccines.

CONCLUSIONS

Our study provides important genetic insight into the interspecies transmission and evolution of PRV within and between different hosts that warrant additional surveillance.

Pathogenicity of an FAdV-4 isolate to chickens and its genomic analysis

Fowl adenovirus serotype 4 (FAdV-4) strain SD1511 was isolated from chickens with severe inclusion body hepatitis and hydropericardium syndrome in Shandong Province, China. The isolate was cultured in primary chicken embryo kidney cells. A study of pathogenicity indicated that SD1511 readily infected 7-35-d-old chickens by intramuscular injection and intranasal and oral routes, causing 50%-100% mortality. The 35-d-old chickens suffered more severe infection than 7- and 21-d-old chickens with mortality highest in the intramuscular injection group. The serum from surviving chickens showed potent viral neutralizing capability. The complete genome of SD1511 was sequenced and analyzed. The strain was found to belong to the FAdV-4 cluster with more than 99% identity with the virulent FAdV-4 strains isolated in China in recent years except for some distinct variations, including deletions of open reading frame 27 (ORF27), ORF48, and part of ORF19. Our findings suggest that SD1511 might be used as a prototype strain for the study of pathogenesis and vaccine development.

Genome Characteristics and Evolution of Pseudorabies Virus Strains in Eastern China from 2017 to 2019

Since late 2011, outbreaks of pseudorabies virus (PRV) have occurred in southern China causing major economic losses to the pig industry. We previously reported that variant PRV forms and recombination in China could be the source of continued epidemics. Here, we analyzed samples from intensive pig farms in eastern China between 2017 and 2019, and sequenced the main glycoproteins (gB, gC, gD, and gE) to study the evolution characteristics of PRV. Based on the gC gene, we found that PRV variants belong to clade 2 and detected a founder effect during by the PRV epidemic. In addition, we detected inter- and intra-clade recombination; in particular, inter-clade recombination in the gB genes of strains FJ-ZXF and FJ-W2, which were recombinant with clade 1 strains. We also found specific amino-acid changes and positively selected sites, possibly associated with functional changes. This analysis of the emergence of PRV in China illustrates the need for continuous monitoring and the development of vaccines against specific variants of PRV.

Design, synthesis and biological evaluation of 8-(2-amino-1-hydroxyethyl)-6-hydroxy-1,4-benzoxazine-3(4H)-one derivatives as potent β2-adrenoceptor agonists

A series of β₂-adrenoceptor agonists with an 8-(2-amino-1-hydroxyethyl)-6-hydroxy-1,4-benzoxazine-3(4H)-one moiety is presented. The stimulatory effects of the compounds on human β₂-adrenoceptor and β₁-adrenoceptor were characterized by a cell-based assay. Their smooth muscle relaxant activities were tested on isolated guinea pig trachea. Most of the compounds were found to be potent and selective agonists of the β₂-adrenoceptor. One of the compounds, (R)-18c, possessed a strong β₂-adrenoceptor agonistic effect with an EC₅₀ value of 24 pM. It produced a full and potent airway smooth muscle relaxant effect same as olodaterol. Its onset of action was 3.5 min and its duration of action was more than 12 h in an in vitro guinea pig trachea model of bronchodilation. These results suggest that (R)-18c is a potential candidate for long-acting β₂-AR agonists.

Abstract 566: Branched Chain Ketoacid Dehydrogenase Kinase Inhibition Alters Substrate Utilization and Gene Expression in Myocytes

Circulating increases in branched chain amino acid (BCAA) levels have long been associated with type II diabetes and metabolic syndrome. Emerging data also suggest that impaired BCAA catabolism may play a role in heart failure progression. BCAA are catabolized via the branched chain ketoacid (BCKA) dehydrogenase enzyme complex (BCKDH). BCKD kinase (BCKDK) is a negative regulator of BCAA catabolism through its inhibitory phosphorylation of the BCKDHE1a subunit, and the phosphatase PPM1k dephosphorylates this same site to activate BCAA catabolism. Using an inhibitor of BCKDK (BT2), BCAA catabolism is increased in vivo. Here, we utilized metabolomics to evaluate the contribution of BCAA catabolism to substrate preference in heart and skeletal muscle. Surprisingly, BCKDK inhibition with BT2 had no effect on incorporation of glucose into TCA cycle intermediates in heart or skeletal muscle. Because others have recently shown that the primary site of BCAA catabolism is skeletal muscle, we knocked down BCKDK and PPM1k in human skeletal myocytes to further investigate how BCKDK loss or inhibition affects substrate utilization. Similar to our in vivo observations, knockdown of BCKDK and PPM1k had no effect on glucose and pyruvate utilization in a mitochondrial function assay. However, an increase in maximal respiration was observed after BCKDK knockdown when fatty acids were used. To evaluate the mechanisms underlying this increase we then performed RNAseq in these cells after BCKDK and PPM1K knockdown and observed changes in a number of genes that may explain these alterations in substrate utilization. Finally, we performed C13 BCAA metabolomics in human skeletal myocytes after BT2 treatment or knockdown of BCKDK and PPM1k. Using BT2, we observed a dose-responsive reduction in BCKA production from C13 BCAA by the muscle cells as expected; however, though BCKA production was increased after PPM1k was knocked down, we surprisingly did not observe a decrease in BCKA production after BCKDK knockdown. Collectively these data suggest that BCKDK inhibition may improve metabolism and cardiac function by altering substrate preference in skeletal myocytes.

Genetic Analysis and Evolutionary Changes of the Torque teno sus Virus

The torque teno sus virus (TTSuV) is an emerging virus threating the Suidae species of unclear pathogenicity, although it was previously reported as a worsening factor of other porcine diseases, in particular, porcine circovirus associated disease (PCVAD). Here, a comprehensive codon usage analysis of the open reading frame 1 (ORF1), which encodes the viral capsid protein, was undertaken for the first time to reveal its evolutionary history. We revealed independent phylogenetic processes for the two genera during TTSuV evolution, which was confirmed by principal component analysis (PCA). A low codon usage bias was observed in different genera and different species, with Kappatorquevirus a (TTSuVk2a) displaying the highest, which was mainly driven by mutation pressure and natural selection, especially natural selection. Overall, ATs were more abundant than GCs, along with more A-ended synonymous codons in relative synonymous codon usage (RSCU) analysis. To further confirm the role of natural selection and TTSuV adaptation to the Suidae species, codon adaptation index (CAI), relative codon deoptimization index (RCDI), and similarity index (SiD) analyses were performed, which showed different adaptations for different TTSuVs. Importantly, we identified a more dominant role of Sus scrofa in the evolution of Iotatorquevirus (TTSuV1), with the highest CAI values and lowest RCDI values compared to Sus scrofa domestica. However, in TTSuVk2, the roles of Sus scrofa and Sus scrofa domestica were the same, regarding codon usage, with similar CAI and RCDI values. Our study provides a new perspective of the evolution of TTSuV and valuable information to develop control measures against TTSuV.

Genetic analysis and evolutionary changes of Porcine circovirus 2

Porcine circovirus 2 (PCV2) has been increasingly isolated worldwide and represents one of the main causes of economic losses in the swine industry. During evolution, PCV2 has diverged into different genotypes and several recombinant strains have been identified. In this study, we performed thorough genetic, evolutionary and codon usage analyses using 1065 non-recombinant open reading frame 2 (ORF2) sequences from NCBI. Based on ML and Bayesian methods of the ORF2 gene, five main genotypes were defined including, PCV2a, PCV2b, PCV2c, PCV2d and PCV2e. The different genotypes displayed a variable degree of codon usage bias, mainly influenced by natural selection. Moreover, the host adaptation of these PCV2 genotypes to different hosts was analyzed for the first time showing that PCV2 is more adapted to swine than bats. Swine was especially relevant in shaping the PCV2b and PCV2d genomes according the Codon adaptation index (CAI) and Similarity index (SiD). When a broader range of circoviruses was considered, a certain incongruence between the phylogenetic history of these viruses and that of their hosts was observed, suggesting that cross-species transmission has played a major role during circoviruses evolution. Our study provides a new perspective of the evolution of Porcine circoviruses and may serve to aid future research on PCV2 origin and evolution patterns.

Detection and spike gene characterization in porcine deltacoronavirus in China during 2016-2018

Porcine deltacoronavirus (PDCoV) has been emerging in several swine-producing countries for years. In our study, 719 porcine diarrhoea samples from 18 provinces in China were collected for PDCoV and porcine epidemic diarrhoea virus (PEDV) detection. The epidemiological survey revealed that the positive rates of PDCoV, PEDV and coinfection were 13.07%, 36.72% and 4.73%, respectively. The entire spike (S) genes of eleven detected PDCoV strains were sequenced. Phylogenetic analysis showed that the majority of PDCoVs could be divided into three lineages: the China lineage, the USA/Japan/South Korea lineage and the Viet Nam/Laos/Thailand lineage. The China and the Viet Nam/Laos/Thailand lineages showed much greater genetic divergences than the USA/Japan/South Korea lineage. The present study detected one new monophyletic branch that contained three PDCoVs from China, and this branch was separated from the China lineage but closely related to the Viet Nam/Laos/Thailand lineage. The strain CH-HA2-2017, which belongs to this new branch, had a possible recombination event between positions 27 and 1234. Significant amino acid substitutions of PDCoV S proteins were analysed and displayed with a three-dimensional cartoon diagram. The visual spatial location of these substitutions gave a conformational-based reference for further studies on the significance of critical sites on the PDCoV S protein.

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The majority of global PDCoVs could be divided into three lineages.

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Three sequenced PDCoVs from China were closely related to the Viet Nam/Laos/Thailand lineage.

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The China lineage showed the greatest genetic divergence.

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One sequenced strain CH-HA2–2017 had a possible recombination event.

Insights into the genetic and host adaptability of emerging porcine circovirus 3

Porcine circovirus 3 (PCV3) was found to be associated with reproductive disease in pigs, and since its first identification in the United States, it subsequently spread worldwide, especially in China, where it might pose a potential threat to the porcine industry. However, no exhaustive analysis was performed to understand its evolution in the prospect of codon usage pattern. Here, we performed a deep codon usage analysis of PCV3. PCV3 sequences were classified into two clades: PCV3a and PCV3b, confirmed by principal component analysis. Additionally, the degree of codon usage bias of PCV3 was slightly low as inferred from the analysis of the effective number of codons. The codon usage pattern was mainly affected by natural selection, but there was a co-effect of mutation pressure and dinucleotide frequency. Moreover, based on similarity index analysis, codon adaptation index analysis and relative codon deoptimization index analysis, we found that PCV3 might pose a potential risk to public health though with unknow pathogenicity. In conclusion, this work reinforces the systematic understanding of the evolution of PCV3, which was reflected by the codon usage patterns and fitness of this novel emergent virus.

Design, synthesis and biological evaluation of 5-(2-amino-1-hydroxyethyl)-8-hydroxyquinolin-2(1H)-one derivatives as potent β2-adrenoceptor agonists

A series of novel β₂-adrenoceptor agonists with a 5-(2-amino-1-hydroxyethyl)-8-hydroxyquinolin-2(1H)-one moiety was designed, synthesized and evaluated for biological activity in human embryonic kidney 293 cells and isolated guinea pig trachea. Compounds 9g and (R)-18c exhibited the most excellent β₂-adrenoceptor agonistic effects and high β₂/β₁-selectivity with EC₅₀ values of 36 pM for 9g and 21 pM for (R)-18c. They produced potent airway smooth muscle relaxant effects with fast onset of action and long duration of action in an in vitro guinea pig trachea model of bronchodilation. These results support further development of the two compounds into drug candidates.

Origin, Genetic Diversity, and Evolutionary Dynamics of Novel Porcine Circovirus 3

Porcine circovirus 3 (PCV3) is a novel virus associated with acute PDNS (porcine dermatitis and nephropathy syndrome)-like clinical signs identified by metagenomic sequencing from swine. Its high occurrence may pose a potential threat to the swine industry worldwide. The processes resulting in the emergence and spread of PCV3 remain poorly understood. Herein, the possible origin, genotypes, and evolutionary dynamics of PCV3 based on available genomic sequences are determined. The closest ancestor of PCV3 is found to be within the clade 1 bat CVs. Using different phylogenetic methods, two major genotypes are identified, PCV3a and PCV3b. It is found that the effective population size of PCV3 increased rapidly during late 2013 to early 2014 and this is associated with the diversification of PCV3a and PCV3b. A relatively high effective reproductive number (Re) value and higher evolutionary rate were found compared to other single-stranded DNA viruses, and positive selection on codons 122 and 320 (24 of ORF2) is identified. It is hypothesized that this, together with the prediction of a potential change of an antigenic epitope at position 320, might have allowed PCV3 to escape from the host immune response. Overall, this study has important implications for understanding the ongoing PCV3 cases worldwide and will guide future efforts to develop effective preventive and control measures.

Synthesis, biological evaluation and molecular modeling of 2-amino-2-phenylethanol derivatives as novel β2-adrenoceptor agonists

A novel series of 2-amino-2-phenylethanol derivatives were developed as β₂-adrenoceptor agonists. Among them, 2-amino-3-fluoro-5-(2-hydroxy-1-(isopropylamino)ethyl)benzonitrile (compound 2f) exhibited the highest activity (EC₅₀ = 0.25 nM) in stimulating β₂-adrenoceptor-mediated cellular cAMP production with a 763.6-fold selectivity over the β₁-adrenoceptor. The (S)-isomer of 2f was subsequently found to be 8.5-fold more active than the (R)-isomer. Molecular docking was performed to determine the putative binding modes of this new class of β₂-adrenoceptor agonists. Taken together, these data show that compound 2f is a promising lead compound worthy of further study for the development of β₂-adrenoceptor agonists.

Discovery of Fragment-Derived Small Molecules for in Vivo Inhibition of Ketohexokinase (KHK)

Increased fructose consumption and its subsequent metabolism have been implicated in hepatic steatosis, dyslipidemia, obesity, and insulin resistance in humans. Since ketohexokinase (KHK) is the principal enzyme responsible for fructose metabolism, identification of a selective KHK inhibitor may help to further elucidate the effect of KHK inhibition on these metabolic disorders. Until now, studies on KHK inhibition with small molecules have been limited due to the lack of viable in vivo pharmacological tools. Herein we report the discovery of 12, a selective KHK inhibitor with potency and properties suitable for evaluating KHK inhibition in rat models. Key structural features interacting with KHK were discovered through fragment-based screening and subsequent optimization using structure-based drug design, and parallel medicinal chemistry led to the identification of pyridine 12.

Targeting C3a/C5a receptors inhibits human mesangial cell proliferation and alleviates immunoglobulin A nephropathy in mice

Complement activation has a deep pathogenic influence in immunoglobulin (Ig)A nephropathy (IgAN). C3a and C5a, small cleavage fragments generated by complement activation, are key mediators of inflammation. The fragments exert broad proinflammatory effects by binding to specific receptors (C3aR and C5aR, respectively). However, no studies thus far have investigated the effects of C3a, C5a and their receptors on IgAN. We observed that C3aR and C5aR antagonists repressed IgA-induced cell proliferation and interleukin (IL)-6 and monocyte chemotactic protein 1 (MCP-1) production in cultured human mesangial cells (HMCs). Furthermore, an IgAN mouse model induced by Sendai virus infection was employed to investigate the effects of C3aR and C5aR on IgAN in vivo for the first time. Wild-type (WT) and several knock-out mouse strains (C3aR^-/- or C5aR^-/- ) were immunized intranasally with increasing doses of inactivated virus for 14 weeks and were subjected to two intravenous viral challenges during the time-period indicated. In the Sendai virus-induced IgAN model, C3aR/C5aR-deficient mice had significantly reduced proteinuria, lower renal IgA and C3 deposition, less histological damage and reduced mesangial proliferation compared with WT mice. Both C3aR deficiency and C5aR deficiency, especially C3aR deficiency, inhibited renal tumour necrosis factor (TNF)-α, transforming growth factor (TGF)-β, IL-1β, IL-6 and MCP-1 expression significantly. However, C3aR/C5aR-deficient and WT mice with IgAN did not differ with respect to their blood urea nitrogen (BUN) and serum creatinine levels. Our findings provide further support for the idea that C3aR and C5aR are crucially important in IgAN, and suggest that pharmaceutically targeting C3aR/C5aR may hold promise for the treatment of IgAN.

High-frequency repetitive transcranial magnetic stimulation over the left DLPFC for major depression: Session-dependent efficacy: A meta-analysis

Background

Depression is a major debilitating psychiatric disorder. Current antidepressant drugs are often associated with side effects or treatment resistance. The aim of this meta-analysis was to evaluate therapeutic effects of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) in major depression (MD).

Methods

The medical data bases of PubMed, Medline, Embase and Cochrane Central Register were searched for randomized controlled trials (RCTs) reporting the therapeutic effects of high-frequency rTMS for depression, which were published in English between January 1990 and June 2016. The index terms were “depress*”, “depression” and “transcranial magnetic stimulation”. Depression outcome data of different sessions (5, 10, 15, and 20 sessions of rTMS treatment) were extracted and synthesized by calculating standardized mean difference (SMD) with 95% confidence intervals (CI) by using a random-effect model. Within each session group, the subgroup analyses based on the number of pulses (≤ 1000, 1200–1500, 1600–1800, and 2000–3000) were also conducted.

Results

Thirty RCTs with a total of 1754 subjects including 1136 in the rTMS group and 618 in the sham group were included in this meta-analysis. rTMS had a significant overall therapeutic effect on depression severity scores (SMD = −0.73, P < 0.00001). The five, 10, 15, 20 sessions of rTMS treatments yielded the significant mean effect sizes of −0.43, −0.60, −1.13, and −2.74, respectively. In the four groups (5, 10, 15, 20 sessions), the maximal mean effect size was all obtained in the subgroup of 1200–1500 pulses per day (−0.97, −1.14, −1.91, −5.47; P < 0.05).

Conclusions

The increasing of HF-rTMS sessions is associated with the increased efficacy of HF-rTMS in reducing depressed patients’ symptom severity. A total number of pulses of 1200–1500 per day appear to deliver the best antidepressant effects of HF-rTMS.

Effects of soybean resistance on variability in life history traits of the higher trophic level parasitoid Meteorus pulchricornis (Hymenoptera: Braconidae)

To extrapolate the influence of plant cultivars varying in resistance levels to hosts on parasitoid life history traits, we estimated variation in parasitoid developmental and reproductive performances as a function of resistance in soybean cultivars, which were randomly chosen from a line of resistant genotypes. Our study showed that the parasitoid Meteorus pulchricornis varied widely in offspring survival and lifetime fecundity, but varied slightly in development time and adult body size, in response to the soybean cultivars that varied in resistance to the host Spodoptera litura. Furthermore, the variability in survival and lifetime fecundity was different between attacking the 2nd and the 4th instar host larvae, varying more in survival but less in lifetime fecundity when attacking the 4th than 2nd instar larvae. Our study provides further evidence supporting that plant resistance to herbivorous hosts have variable effects on different life history traits of higher trophic level parasitoids.