HiCube: interactive visualization of multiscale and multimodal Hi-C and 3D genome data.

SUMMARY: HiCube is a lightweight web application for interactive visualization and exploration of diverse types of genomics data at multiscale resolutions. Especially, HiCube displays synchronized views of Hi-C contact maps and 3D genome structures with user-friendly annotation and configuration tools, thereby facilitating the study of 3D genome organization and function. AVAILABILITY AND IMPLEMENTATION: HiCube is implemented in Javascript and can be installed via NPM. The source code is freely available at GitHub (https://github.com/wmalab/HiCube).

Transport Properties with Multiple Functions of Fe@C60-GNR Single Molecule.

Encouraged by the successful fabrication of C60-GNR (GNR=graphene nanoribbon) single-molecule transistors in experiments, four Fe-containing derived double-layered devices of Fe@C60-GNR are designed by employing different electrode linkages and their transport properties are investigated by using density functional theory (DFT) and nonequilibrium Green's function (NEGF) methods. Regardless of electrode connection, all these devices give rise to a smaller negative differential resistance (NDR) peak at V=0.2 and a higher peak at 1.2 V, suggesting their stable maneuverability as molecular devices and good candidates for developing on(off)-off(on)-on(off) current switches. The macroscopic NDR performance depends on the delocalization character and the crossing mechanism of the frontier orbitals. The peak-to-valley current ratios (Rmax) range from 454 to 2737, determined by the electrode linkage. Such a large Rmax-value is necessary for developing dynamic random-access memory (DRAM) cells. Encapsulating the Fe atom inside C60 not only improves the conductivity but also introduces the spin-polarized transport property. The spin-filtering efficiency (SFE) of almost all devices oscillates up and down in response to the bias voltage, indicating the possibility of designing on(off)-off(on)-on(off) spin switches and up-down spin switches. All these fascinating properties provide an important clue for designing similar molecular devices with multiple functions by trapping magnetic transition metal atoms inside fullerenes.

Risk factors for short-term prognosis of end-stage liver disease complicated by invasive pulmonary aspergillosis.

BACKGROUND AND AIM: Patients with end-stage liver disease (ESLD) are susceptible to invasive pulmonary aspergillosis (IPA). This study aimed to investigate the risk factors affecting the occurrence and short-term prognosis of ESLD complicated by IPA. METHODS: This retrospective case-control study included 110 patients with ESLD. Of them, 27 ESLD-IPA received antifungal therapy with amphotericin B (AmB); 27 AmB-free-treated ESLD-IPA patients were enrolled through 1:1 propensity score matching. Fifty-six ESLD patients with other comorbid pulmonary infections were enrolled as controls. The basic features of groups were compared, while the possible risk factors affecting the occurrence and short-term outcomes of IPA were analyzed. RESULTS: Data analysis revealed invasive procedures, glucocorticoid exposure, and broad-spectrum antibiotic use were independent risk factors for IPA. The 54 patients with ESLD-IPA exhibited an overall treatment effectiveness and 28-d mortality rate of 50.00% and 20.37%, respectively, in whom patients treated with AmB-containing showed higher treatment efficacy than patients treated with AmB-free antifungal regimens (66.7% vs. 33.3%, respectively, χ2 = 6.000, P = 0.014). Multivariate logistic regression analysis revealed that the treatment regimen was the only predictor affecting patient outcomes, with AmB-containing regimens were 4.893 times more effective than AmB-free regimens (95% CI, 1.367-17.515; P = 0.015). The only independent predictors affecting the 28-d mortality rate were neutrophil-to-lymphocyte ratio and IPA diagnosis (OR = 1.140 and 10.037, P = 0.046 and 0.025, respectively). CONCLUSIONS: Glucocorticoid exposure, invasive procedures, and broad-spectrum antibiotic exposure increased the risk of IPA in ESLD patients. AmB alone or combined with other antifungals may serve as an economical, safe, and effective treatment option for ESLD-IPA.

Insulin Use Is Associated With Improved Outcomes in Critically Ill Patients With Acute Pancreatitis: A Retrospective Matched Cohort Study.

BACKGROUND: Severe acute pancreatitis (SAP) has a mortality of 30% with no current targeted therapy. The potential protective effect of insulin on AP has been reported and needs to be confirmed. Thus, we aim to examine the effect of insulin treatment on the outcome of AP patients. METHODS: A retrospective study was performed using data from the Medical Information Mart for Intensive Care (MIMIC) database. Kruskal-Wallis test, t-tests, and Pearson's chi-squared test were used to compare differences between groups. Propensity score matching and further nearest neighbor matching were used to construct a matched cohort. Cox proportional hazards regression analyses, logistic regression analyses, and the doubly robust estimation method were used to assess the relationship between insulin use and mortality. RESULTS: Nine hundred patients were enrolled in the final analysis. Insulin was associated with better outcomes in AP patients admitted to ICU, and could act as an independent predictor for 30-day mortality (HR = 0.36, 95% CI = 0.24-0.55). Subgroup analysis showed that AP patients with heart failure or without kidney disease or respiratory failure may not benefit from insulin treatment. CONCLUSIONS: Insulin treatment is independently associated with lower 30-day mortality in AP patients, except for those with heart failure or without kidney disease or respiratory failure.

A Single Vaccine Protects against SARS-CoV-2 and Influenza Virus in Mice.

The ongoing SARS-CoV-2 pandemic poses a severe global threat to public health, as do influenza viruses and other coronaviruses. Here, we present chimpanzee adenovirus 68 (AdC68)-based vaccines designed to universally target coronaviruses and influenza. Our design is centered on an immunogen generated by fusing the SARS-CoV-2 receptor-binding domain (RBD) to the conserved stalk of H7N9 hemagglutinin (HA). Remarkably, the constructed vaccine effectively induced both SARS-CoV-2-targeting antibodies and anti-influenza antibodies in mice, consequently affording protection from lethal SARS-CoV-2 and H7N9 challenges as well as effective H3N2 control. We propose our AdC68-vectored coronavirus-influenza vaccine as a universal approach toward curbing respiratory virus-causing pandemics. IMPORTANCE The COVID-19 pandemic exemplifies the severe public health threats of respiratory virus infection and influenza A viruses. The currently envisioned strategy for the prevention of respiratory virus-causing diseases requires the comprehensive administration of vaccines tailored for individual viruses. Here, we present an alternative strategy by designing chimpanzee adenovirus 68-based vaccines which target both the SARS-CoV-2 receptor-binding-domain and the conserved stalk of influenza hemagglutinin. When tested in mice, this strategy attained potent neutralizing antibodies against wild-type SARS-CoV-2 and its emerging variants, enabling an effective protection against lethal SARS-CoV-2 challenge. Notably, it also provided complete protection from lethal H7N9 challenge and efficient control of H3N2-induced morbidity. Our study opens a new avenue to universally curb respiratory virus infection by vaccination.

Evaluation of the coracoid bone tunnel placement on Dog Bone™ button fixation for acromioclavicular joint dislocation: a cadaver study combined with finite element analysis.

BACKGROUND: Dog Bone™ button fixation is frequently used to treat acromioclavicular joint (ACJ) dislocation. However, various studies have reported complications after fixation. OBJECTIVE: To investigate the effect of the coracoid bone tunnel location on the treatment of ACJ dislocation through single-tunnel coracoclavicular (CC) ligament fixation with the Dog Bone™ button. METHODS: Six cadaveric shoulders were used. Each specimen was subjected to five testing conditions in the following order: (1) normal ACJ (Gn); (2) acromioclavicular and CC ligaments were removed (G0); (3) CC ligament reconstruction was performed using the Dog Bone™ technique, and the coracoid bone tunnel was at the center of the coracoid base (G1); (4) reconstruction was performed at 5 mm distal from the G1 site, along the axis of the coracoid (G2); (5) reconstruction was performed at 10 mm distal from the G1 site, along the axis of the coracoid (G3). The angles of pronation and supination of the clavicle under the same load (30 N) were measured. Next, a finite element (FE) model was created using computed tomography (CT) images of the normal shoulder. Model 1 (M1), model 2 (M2), and model 3 (M3) correspond to G1, G2, and G3, respectively. A force of 70 N was applied as a vertical upward load to the distal clavicle. Subsequently, the von Mises stress, the strain LE along the FiberWire, and the displacement nephogram of the three models were obtained. RESULTS: After single-tunnel CC ligament fixation using the Dog Bone™ technique, the clavicle in the G2 group (20.50 (19.50, 21.25) °, 20.00 (18.75, 21.25) °) had the best rotational stability. The peak von Mises stress, the strain LE along the FiberWire, and the maximum displacement were smaller in M2 than in M1 and M3. CONCLUSIONS: When the coracoid bone tunnel was located 5 mm anterior to the center of the coracoid base (along the axis of the coracoid), the clavicle showed greater rotational stability.

MRPL12 Acts as A Novel Prognostic Biomarker Involved in Immune Cell Infiltration and Tumor Progression of Lung Adenocarcinoma.

Mitochondrial ribosomal protein L7/L12 (MRPL12) is a member of the mitochondrial ribosomal proteins (MRPs). However, the biological function of MRPL12 in lung adenocarcinoma (LUAD) remains unclear. The expression and prognostic value of MRPL12 in LUAD were systematically analyzed using UALCAN, TIMER, HPA, Kaplan-Meier plotter, and GEPIA databases. The relationship between MRPL12 and immune infiltrates was investigated using TIMER and TISIDB databases. The clinical significance of MRPL12 in LUAD patients was validated using a tissue microarray (TMA). Cellular functional experiments were carried out to examine the influences of MRPL12 knockdown on cell proliferation, migration, and invasion. MRPL12 was significantly upregulated in LUAD samples, and high MRPL12 expression was correlated with worse prognosis. MRPL12 expression was markedly associated with immunomodulators, chemokines, and infiltration levels of multiple immune cells. Furthermore, TMA results confirm the upregulation of MRPL12 expression in LUAD, and MRPL12 was identified as an independent prognostic factor in LUAD patients. MRPL12 knockdown inhibited proliferation, migration, and invasion of LUAD cells. These data indicate that MRPL12 is a prognostic biomarker and correlated with immune infiltrates in LUAD. Therefore, MRPL12 shows potential as a therapeutic target for LUAD.

Efficacy of an ALDH peptide-based dendritic cell vaccine targeting cancer stem cells.

Cancer immunotherapies may be limited by their failure to target cancer stem cells (CSCs). We previously described an approach to target these cells using a dendritic cell (DC) vaccine primed with lysates of CSCs identified by aldehyde dehydrogenase (ALDH). However, its clinical application is limited by the difficulty of obtaining adequate amounts of tumor from patient to make CSC lysate for vaccine preparation. To address this issue, we evaluated targeting ALDHhigh CSCs using two antigenic peptides derived from ALDH in D5 melanoma model in both protection and therapeutic settings. ALDH 1A1 or 1A3 peptide-DC vaccines primed cytotoxic T lymphocytes (CTLs) that specifically killed ALDHhigh D5 CSCs, with ALDH 1A1 + 1A3 dual peptides-DC vaccine mediating an additive CTL effect compared to single peptide-DC vaccines. In a tumor challenge model, ALDH peptide-DC vaccines induced significant protective immunity suppressing D5 tumor growth with the dual peptides-DC vaccine being superior to each peptide individually. In a therapeutic model, dual peptide-DC vaccine resulted in significant tumor growth suppression with anti-PD-L1 administration significantly augmenting this effect. Immune monitoring studies revealed that ALDH dual peptides-DC vaccination elicited strong T cell (CTL & IFNγ Elispot) and antibody immunity targeting ALDHhigh CSCs, resulting in significant reduction of ALDHhigh D5 CSCs. ALDH dual peptides-DC vaccination plus anti-PD-L1 administration resulted in increased recruitment of CD3+ TILs in the residual tumors and further reduction of ALDHhigh D5 CSCs. ALDH peptide(s)-based vaccine may allow for clinical translation via immunological targeting of ALDHhigh CSCs. Furthermore, this vaccine augments the efficacy of immune checkpoint blockade.

EnHiC: learning fine-resolution Hi-C contact maps using a generative adversarial framework.

MOTIVATION: The high-throughput chromosome conformation capture (Hi-C) technique has enabled genome-wide mapping of chromatin interactions. However, high-resolution Hi-C data requires costly, deep sequencing; therefore, it has only been achieved for a limited number of cell types. Machine learning models based on neural networks have been developed as a remedy to this problem. RESULTS: In this work, we propose a novel method, EnHiC, for predicting high-resolution Hi-C matrices from low-resolution input data based on a generative adversarial network (GAN) framework. Inspired by non-negative matrix factorization, our model fully exploits the unique properties of Hi-C matrices and extracts rank-1 features from multi-scale low-resolution matrices to enhance the resolution. Using three human Hi-C datasets, we demonstrated that EnHiC accurately and reliably enhanced the resolution of Hi-C matrices and outperformed other GAN-based models. Moreover, EnHiC-predicted high-resolution matrices facilitated the accurate detection of topologically associated domains and fine-scale chromatin interactions. AVAILABILITY AND IMPLEMENTATION: EnHiC is publicly available at https://github.com/wmalab/EnHiC. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Carbon Starved Anther modulates sugar and ABA metabolism to protect rice seed germination and seedling fitness.

Seed germination is critical for plant survival and agricultural production, which is affected by both internal seed factors and external environmental conditions. However, the genetic basis and underlying molecular mechanisms of early seed germination in crops remain largely unclear. Here, we report that R2R3 MYB transcription factor Carbon Starved Anther (CSA) is expressed specifically in Oryza sativa embryo and aleurone in response to seed imbibition, peaking at 3-6 h and undetectable by 24-h post-imbibition. CSA seeds germinated more quickly than wild-type rice seeds and had higher levels of amylase activity, glucose, and inactive abscisic acid-glucose ester (ABA-GE), but lower levels of ABA. Through analyzing the CSA-associated transcriptome and CSA binding to downstream target genes, we identified two glycolytic genes as direct CSA targets. CSA inhibits Amylase 3A expression to limit glucose production from starch and activates Os3BGlu6 expression to promote de-conjugation of ABA-GE to ABA; these functions serve to slow germination and improve seedling resilience to abiotic stress in the first 3 weeks of growth. Therefore, this study unveils a protection mechanism conferred by CSA during early seed germination by balancing glucose and ABA metabolism to optimize seed germination and stress response fitness.

Investigate the effect of COVID-19 inactivated vaccine on sperm parameters and embryo quality in in vitro fertilization.

Since the reproductive toxicity of COVID-19 vaccines have not been assessed in previous clinical trials, and studies have shown that SARS-CoV-2 is associated with a decrease in sperm parameters. Although it has been reported that the mRNA SARS-CoV-2 vaccines do not adversely affect semen parameters, whether this conclusion applies to inactivated vaccines remains unclear. Here, we conducted a study among patients who accepted in vitro fertilization (IVF) at the reproductive centre between June and August of 2021. In the enrolled cases, men who have completed two doses of COVID-19 inactivated vaccine were included in "vaccine group" (N = 105), and those who were not vaccinated were included in "control group" (N = 155). In this study, we compare the sperm parameters and embryo quality between these two groups. Our data showed that the sperm parameters were similar in terms of volume, sperm concentration, sperm count, progressive motility, total motility and total motile sperm count between these two groups. Similarly, no significant differences were observed in IVF outcomes. The mean number of 2PN, cleavage-stage embryos, blastocysts, and good-quality blastocysts was 8.59 ± 4.47, 5.06 ± 3.17 and 2.08 ± 1.79 in vaccine group, 7.75 ± 4.14, 4.34 ± 3.06 and 1.74 ± 1.54 in control group, respectively. The high-quality blastocyst rate was 41.05% (218 of 531) in vaccine group and 40.03% (269 of 672) in control group (p > 0.05). In addition, no differences were observed in biochemical and clinical pregnancy rates between the two groups. In summary, our results revealed that COVID-19 inactivated vaccine administration exhibited no negative effect on sperm parameters and embryo quality in IVF.

Research on Waste Plastics Classification Method Based on Multi-Scale Feature Fusion.

Microplastic particles produced by non-degradable waste plastic bottles have a critical impact on the environment. Reasonable recycling is a premise that protects the environment and improves economic benefits. In this paper, a multi-scale feature fusion method for RGB and hyperspectral images based on Segmenting Objects by Locations (RHFF-SOLOv1) is proposed, which uses multi-sensor fusion technology to improve the accuracy of identifying transparent polyethylene terephthalate (PET) bottles, blue PET bottles, and transparent polypropylene (PP) bottles on a black conveyor belt. A line-scan camera and near-infrared (NIR) hyperspectral camera covering the spectral range from 935.9 nm to 1722.5 nm are used to obtain RGB and hyperspectral images synchronously. Moreover, we propose a hyperspectral feature band selection method that effectively reduces the dimensionality and selects the bands from 1087.6 nm to 1285.1 nm as the features of the hyperspectral image. The results show that the proposed fusion method improves the accuracy of plastic bottle classification compared with the SOLOv1 method, and the overall accuracy is 95.55%. Finally, compared with other space-spectral fusion methods, RHFF-SOLOv1 is superior to most of them and achieves the best (97.5%) accuracy in blue bottle classification.

Rapamycin prevents heterotopic ossification by inhibiting the mTOR pathway and oxidative stress.

Rapamycin (RAPA), which was first described as an anti-fungal agent, is a potent immunosuppressant that suppresses tumors and inhibits the mTOR signaling pathway. Heterotopic ossification (HO) is abnormal bone formation outside the skeletal system (e.g., in muscles, tendons, articular capsules and other soft tissues), often due to trauma or injury. There are currently no drugs available to treat traumatic HO, largely due to limited understanding of the disease. In this study, we focused on the role of oxidative stress (OS) in the early stage of traumatic HO, and explored the underlying mechanism of traumatic HO by using RAPA to specifically inhibit the mTOR pathway, which is known to play a role in the pathogenesis of HO. To assess the effects of RAPA in traumatic HO, we used an NSE-BMP4 transgenic mouse model that develops ossification in response to traumatic injury and intramuscular injection of cardiotoxin to initiate injury. These mice were then treated with RAPA or vehicle intraperitoneally every other day for 2 weeks. Our results demonstrate that RAPA can inhibit HO through a number of different mechanisms. We show that OS and a strong inflammatory response contribute to the hypoxia associated with the early stages of HO, and that RAPA inhibits these responses. Furthermore, RAPA reduces the vascularization triggered by mTOR signaling that leads to HO formation. Therefore, we believe that RAPA could be an effective treatment for the early stages of HO.

Two rice MYB transcription factors maintain male fertility in response to photoperiod by modulating sugar partitioning.

Photoperiod-dependent male fertility is a critical enabler of modern hybrid breeding. A MYB transcription factor, CSA, is a key regulator of sugar partitioning in rice anthers, disruption of which causes photoperiod-sensitive male sterility. However, little is known about the molecular mechanisms governing plant fertility in response to photoperiod. Here, we have obtained another rice photoperiod-sensitive male sterile mutant, csa2, which exhibits semi-sterility under long-day (LD) conditions, with normal fertility under short-day (SD) conditions. CSA2 specifically expressed in anthers, and here is shown to be indispensable for sugar partitioning to anthers under LD conditions. The CSA2 protein can restore the fertility of csa mutants under SD conditions when expressed in a CSA-specific pattern, indicating that the two proteins share common downstream regulatory targets. Transcriptomic analyses also reveal discrete regulatory targets in anthers. Furthermore, the regulatory role of CSA2 in sugar transport was influenced by the photoperiod conditions during floral initiation, not simply during anther development. Collectively, we propose that rice evolved at least two MYB proteins, CSA2 and CSA, that regulate sugar transport in anthers under LD and SD conditions, respectively. This finding provides insight into the molecular mechanisms that regulate male fertility in response to photoperiod.

Discovery of novel indole derivatives that inhibit NEDDylation and MAPK pathways against gastric cancer MGC803 cells.

A series of novel indole derivatives were synthesized and evaluated for their antiproliferative activity against three selected cancer cell lines (MGC803, EC-109 and PC-3). Among these analogues, 2-(5-methoxy-1H-indol-1-yl)-N-(4-methoxybenzyl)-N-(3,4,5-trimethoxyphenyl)acetamide (V7) showed the best inhibitory activity against MGC803 cells with an IC50 value of 1.59 µM. Cellular mechanisms elucidated that V7 inhibited colony formation, induced apoptosis and arrested cell cycle at G2/M phase. Importantly, indole analogue V7 inhibited NEDDylation pathway and MAPK pathway against MGC803 cells.

Electronic Properties of Triangle Molybdenum Disulfide (MoS2) Clusters with Different Sizes and Edges.

The electronic structures and transition properties of three types of triangle MoS2 clusters, A (Mo edge passivated with two S atoms), B (Mo edge passivated with one S atom), and C (S edge) have been explored using quantum chemistry methods. The highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap of B and C is larger than that of A, due to the absence of the dangling of edge S atoms. The frontier orbitals (FMOs) of A can be divided into two categories, edge states from S3p at the edge and hybrid states of Mo4d and S3p covering the whole cluster. Due to edge/corner states appearing in the FMOs of triangle MoS2 clusters, their absorption spectra show unique characteristics along with the edge structure and size.

RNA demethylase ALKBH5 prevents pancreatic cancer progression by posttranscriptional activation of PER1 in an m6A-YTHDF2-dependent manner.

BACKGROUND: N6-methyladenosine (m6A) is the most abundant reversible methylation modification of eukaryotic mRNA, and it plays vital roles in tumourigenesis. This study aimed to explore the role of the m6A demethylase ALKBH5 in pancreatic cancer (PC). METHODS: The expression of ALKBH5 and its clinicopathological impact were evaluated in PC cohorts. The effects of ALKBH5 on the biological characteristics of PC cells were investigated on the basis of gain-of-function and loss-of-function analyses. Subcutaneous and orthotopic models further uncovered the role of ALKBH5 in tumour growth. mRNA and m6A sequencing and assays of m6A methylated RNA immunoprecipitation-qPCR (MeRIP-qPCR) were performed to identify the targeted effect of ALKBH5 on PER1. P53-binding sites in the ALKBH5 promoter were investigated by ChIP and luciferase assays to reveal the interplay between ALKBH5 and PER1-activated ATM-CHK2-P53/CDC25C signalling. RESULTS: ALKBH5 loss characterized the occurrence and poor clinicopathological manifestations in patients with PC. Overexpression of ALKBH5 reduced tumoural proliferative, migrative, invasive activities in vitro and ameliorated tumour growth in vivo, whereas ALKBH5 knockdown facilitated PC progression. Mechanistically, ALKBH5 posttranscriptionally activated PER1 by m6A demethylation in an m6A-YTHDF2-dependent manner. PER1 upregulation led to the reactivation of ATM-CHK2-P53/CDC25C signalling, which inhibited cell growth. P53-induced activation of ALKBH5 transcription acted as a feedback loop regulating the m6A modifications in PC. CONCLUSION: ALKBH5 serves as a PC suppressor by regulating the posttranscriptional activation of PER1 through m6A abolishment, which may highlight a demethylation-based approach for PC diagnosis and therapy.

Clinical features of rheumatic patients infected with COVID-19 in Wuhan, China.

OBJECTIVE: The clinical features of rheumatic patients with coronavirus disease 2019 (COVID-19) have not been reported. This study aimed to describe the clinical features of COVID-19 in rheumatic patients and provide information for handling this situation in clinical practice. METHODS: This is a retrospective case series study. Deidentified data, including gender, age, laboratory and radiological results, symptoms, signs, and medication history, were collected from 2326 patients diagnosed with COVID-19, including 21 cases in combination with rheumatic disease, in Tongji Hospital between 13 January and 15 March 2020. RESULTS: Length of hospital stay and mortality rate were similar between rheumatic and non-rheumatic groups, while the presence of respiratory failure was more common in rheumatic cases (38% vs 10%, p<0.001). Symptoms of fever, fatigue and diarrhoea were seen in 76%, 43% and 23% of patients, respectively. There were four rheumatic patients who experienced a flare of rheumatic disease during hospital stay, with symptoms of muscle aches, back pain, joint pain or rash. While lymphocytopaenia was seen in 57% of rheumatic patients, only one patient (5%) presented with leucopenia in rheumatic cases. Rheumatic patients presented with similar radiological features of ground-glass opacity and consolidation. Patients with pre-existing interstitial lung disease showed massive fibrous stripes and crazy-paving signs at an early stage. Five rheumatic cases used hydroxychloroquine before the diagnosis of COVID-19 and none progressed to critically ill stage. CONCLUSIONS: Respiratory failure was more common in rheumatic patients infected with COVID-19. Differential diagnosis between COVID-19 and a flare of rheumatic disease should be considered. TRIAL REGISTRATION NUMBER: ChiCTR2000030795.

AMPKα2 Protects Against the Development of Heart Failure by Enhancing Mitophagy via PINK1 Phosphorylation.

RATIONALE: Mitochondrial dysfunction plays an important role in heart failure (HF). However, the molecular mechanisms regulating mitochondrial functions via selective mitochondrial autophagy (mitophagy) are poorly understood. OBJECTIVE: We sought to determine the role of AMPK (AMP-activated protein kinase) in selective mitophagy during HF. METHODS AND RESULTS: An isoform shift from AMPKα2 to AMPKα1 was observed in failing heart samples from HF patients and transverse aortic constriction-induced mice, accompanied by decreased mitophagy and mitochondrial function. The recombinant adeno-associated virus Serotype 9-mediated overexpression of AMPKα2 in mouse hearts prevented the development of transverse aortic constriction-induced chronic HF by increasing mitophagy and improving mitochondrial function. In contrast, AMPKα2-/- mutant mice exhibited an exacerbation of the early progression of transverse aortic constriction-induced HF via decreases in cardiac mitophagy. In isolated adult mouse cardiomyocytes, AMPKα2 overexpression mechanistically rescued the impairment of mitophagy after phenylephrine stimulation for 24 hours. Genetic knockdown of AMPKα2, but not AMPKα1, by short interfering RNA suppressed the early phase (6 hours) of phenylephrine-induced compensatory increases in mitophagy. Furthermore, AMPKα2 specifically interacted with phosphorylated PINK1 (PTEN-induced putative kinase 1) at Ser495 after phenylephrine stimulation. Subsequently, phosphorylated PINK1 recruited the E3 ubiquitin ligase, Parkin, to depolarized mitochondria, and then enhanced the role of the PINK1-Parkin-SQSTM1 (sequestosome-1) pathway involved in cardiac mitophagy. This increase in cardiac mitophagy was accompanied by the elimination of damaged mitochondria, improvement in mitochondrial function, decrease in reactive oxygen species production, and apoptosis of cardiomyocytes. Finally, Ala mutation of PINK1 at Ser495 partially suppressed AMPKα2 overexpression-induced mitophagy and improvement of mitochondrial function in phenylephrine-stimulated cardiomyocytes, whereas Asp (phosphorylation mimic) mutation promoted mitophagy after phenylephrine stimulation. CONCLUSIONS: In failing hearts, the dominant AMPKα isoform switched from AMPKα2 to AMPKα1, which accelerated HF. The results show that phosphorylation of Ser495 in PINK1 by AMPKα2 was essential for efficient mitophagy to prevent the progression of HF.

Synthesis and Biological Evaluation of Amino Chalcone Derivatives as Antiproliferative Agents.

Chalcone is a common scaffold found in many biologically active compounds. The chalcone scaffold was also frequently utilized to design novel anticancer agents with potent biological efficacy. Aiming to continue the research of effective chalcone derivatives to treat cancers with potent anticancer activity, fourteen amino chalcone derivatives were designed and synthesized. The antiproliferative activity of amino chalcone derivatives was studied in vitro and 5-Fu as a control group. Some of the compounds showed moderate to good activity against three human cancer cells (MGC-803, HCT-116 and MCF-7 cells) and compound 13e displayed the best antiproliferative activity against MGC-803 cells, HCT-116 cells and MCF-7 cells with IC50 values of 1.52 µM (MGC-803), 1.83 µM (HCT-116) and 2.54 µM (MCF-7), respectively which was more potent than the positive control (5-Fu). Further mechanism studies were explored. The results of cell colony formatting assay suggested compound 10e inhibited the colony formation of MGC-803 cells. DAPI fluorescent staining and flow cytometry assay showed compound 13e induced MGC-803 cells apoptosis. Western blotting experiment indicated compound 13e induced cell apoptosis via the extrinsic/intrinsic apoptosis pathway in MGC-803 cells. Therefore, compound 13e might be a valuable lead compound as antiproliferative agents and amino chalcone derivatives worth further effort to improve amino chalcone derivatives' potency.