Cannabinoid Receptor 2-Centric Molecular Feedback Loop Drives Necroptosis in Diabetic Heart Injuries.

BACKGROUND: Diabetic heart dysfunction is a common complication of diabetes. Cell death is a core event that leads to diabetic heart dysfunction. However, the time sequence of cell death pathways and the precise time to intervene of particular cell death type remain largely unknown in the diabetic heart. This study aims to identify the particular cell death type that is responsible for diabetic heart dysfunction and to propose a promising therapeutic strategy by intervening in the cell death pathway. METHODS: Type 2 diabetes models were established using db/db leptin receptor-deficient mice and high-fat diet/streptozotocin-induced mice. The type 1 diabetes model was established in streptozotocin-induced mice. Apoptosis and programmed cell necrosis (necroptosis) were detected in diabetic mouse hearts at different ages. G protein-coupled receptor-targeted drug library was searched to identify potential receptors regulating the key cell death pathway. Pharmacological and genetic approaches that modulate the expression of targets were used. Stable cell lines and a homemade phosphorylation antibody were prepared to conduct mechanistic studies. RESULTS: Necroptosis was activated after apoptosis at later stages of diabetes and was functionally responsible for cardiac dysfunction. Cannabinoid receptor 2 (CB2R) was a key regulator of necroptosis. Mechanically, during normal glucose levels, CB2R inhibited S6 kinase-mediated phosphorylation of BACH2 at serine 520, thereby leading to BACH2 translocation to the nucleus, where BACH2 transcriptionally repressed the necroptosis genes Rip1, Rip3, and Mlkl. Under hyperglycemic conditions, high glucose induced CB2R internalization in a ß-arrestin 2-dependent manner; thereafter, MLKL (mixed lineage kinase domain-like), but not receptor-interacting protein kinase 1 or 3, phosphorylated CB2R at serine 352 and promoted CB2R degradation by ubiquitin modification. Cardiac re-expression of CB2R rescued diabetes-induced cardiomyocyte necroptosis and heart dysfunction, whereas cardiac knockout of Bach2 diminished CB2R-mediated beneficial effects. In human diabetic hearts, both CB2R and BACH2 were negatively associated with diabetes-induced myocardial injuries. CONCLUSIONS: CB2R transcriptionally repressed necroptosis through interaction with BACH2; in turn, MLKL formed a negative feedback to phosphorylate CB2R. Our study provides the integrative view of a novel molecular mechanism loop for regulation of necroptosis centered by CB2R, which represents a promising alternative strategy for controlling diabetic heart dysfunction.

Multi-view Multichannel Attention Graph Convolutional Network for miRNA-disease association prediction.

MOTIVATION: In recent years, a growing number of studies have proved that microRNAs (miRNAs) play significant roles in the development of human complex diseases. Discovering the associations between miRNAs and diseases has become an important part of the discovery and treatment of disease. Since uncovering associations via traditional experimental methods is complicated and time-consuming, many computational methods have been proposed to identify the potential associations. However, there are still challenges in accurately determining potential associations between miRNA and disease by using multisource data. RESULTS: In this study, we develop a Multi-view Multichannel Attention Graph Convolutional Network (MMGCN) to predict potential miRNA-disease associations. Different from simple multisource information integration, MMGCN employs GCN encoder to obtain the features of miRNA and disease in different similarity views, respectively. Moreover, our MMGCN can enhance the learned latent representations for association prediction by utilizing multichannel attention, which adaptively learns the importance of different features. Empirical results on two datasets demonstrate that MMGCN model can achieve superior performance compared with nine state-of-the-art methods on most of the metrics. Furthermore, we prove the effectiveness of multichannel attention mechanism and the validity of multisource data in miRNA and disease association prediction. Case studies also indicate the ability of the method for discovering new associations.

Endoplasmic reticulum stress-related secretory proteins as biomarkers of early myocardial ischemia-induced sudden cardiac deaths.

Early myocardial ischemia-induced sudden cardiac deaths (EMI-SCD) remain a great diagnostic challenge for forensic pathologists due to no gross or non-specific histological pathology. The goal of this study was to assess whether three secretory proteins, related with cellular endoplasmic reticulum stress, can be applied in forensic diagnosis of EMI-SCD. These markers included LMAN2, CAPN-1, and VCP and were compared with two clinically used markers (CK-MB and cTnI). A total of 21 EMI-SCD cases with a mean age of 53.0 (± 10.5) years and a mean ischemia interval of < 2.77 (± 2.56) hours were collected. Another 23 cases (mean 44.6 ± 15.0 year old) that died from non-cardiac causes served as control. Enzyme-linked immunosorbent assay (ELISA) was performed to detect target proteins' serum concentrations in the EMI-SCD and control groups. We found that LMAN2, CAPN-1, and VCP were all significantly increased in the EMI-SCD group as compared with control serum, with the fold changes ranging from 1.48 (p = 0.0022, LMAN2), 1.33 (p = 0.041, CAPN-1), to 1.26 (p = 0.021, VCP), respectively. The concentrations of these proteins remained highly stable within 6 h and were not affected by death time, postmortem interval (< 4 h), age, and month at death. Receiver operating characteristic (ROC) curves showed that the areas under the curve (AUC) were 0.8178 (LMAN2), 0.6988 (CAPN-1), and 0.7267 (VCP), all of which were higher than CK-MB (AUC 0.5590) and cTn-I (AUC 0.5911). The diagnostic specificity (all above 60%) was obviously higher than CK-MB (43.48%) and cTnI (34.78%). In conclusion, LMAN-2, CAPN-1, and VCP could be stable serological biomarkers for diagnosis of EMI-SCD cases.

Second-generation antipsychotics induce cardiotoxicity by disrupting spliceosome signaling: Implications from proteomic and transcriptomic analyses.

Second-generation antipsychotics (SGAs) are first-line drugs that are prescribed for mental disorders in clinic. Severe cardiotoxicity has been widely reported and thus limits their clinical application. This study aimed to identify the common mechanism underlying SGAs-induced cardiotoxicity using dual-omics analyses. Balb/C mice were intraperitoneally injected with two representative SGAs, olanzapine (2.5 mg/kg) and clozapine (25 mg/kg), at clinically comparable doses for 0, 7, 14 and 21 days. Our results showed that both SGAs induced cardiomyocyte degeneration, inflammation infiltration, and cardiac fibrosis, all of which worsened with time. Proteomic analysis revelaed that 22 differentially expressed (DE) proteins overlapped in olanzapine and clozapine-treated hearts. These proteins were significantly enriched in muscle contraction, amino acid metabolism and spliceosomal assembly by GO term analysis and spliceosome signaling was among the top enriched pathways by KEGG analysis. Among the 22 DE proteins, three spliceosome signal proteins were validated in a dynamic detection, and their expression significantly correlated with the extent of SGAs-induced cardiac fibrosis. Following the spliceosome signaling dysregulation, RNA sequencing revealed that alternative splicing events in the mouse hearts were markedly enhanced by SGAs treatments, and the production of vast transcript variants resulted in dysregulation of multiple pathways that are critical for cardiomyocytes adaptation and cardiac remodeling. Pladienolide B, a specific inhibitor of mRNA splicing, successfully corrected SGAs-induced alternative splicing and significantly attenuated the secretion of pro-inflammatory factors and cell deaths induced by SGAs exposure. Our study concluded that the spliceosome signaling was a common pathway driving SGAs cardiotoxicity. Pharmacological inhibition of the spliceosome signaling represents a novel therapeutic strategy against SGAs cardiotoxicity.

Cannabinoid Receptors in Myocardial Injury: A Brother Born to Rival.

Cannabinoid receptors typically include type 1 (CB1) and type 2 (CB2), and they have attracted extensive attention in the central nervous system (CNS) and immune system. Due to more in-depth studies in recent years, it has been found that the typical CB1 and CB2 receptors confer functional importance far beyond the CNS and immune system. In particular, many works have reported the critical involvement of the CB1 and CB2 receptors in myocardial injuries. Both pharmacological and genetic approaches have been used for studying CB1 and CB2 functions in these studies, revealing that the brother receptors have many basic differences and sometimes antagonistic functions in a variety of myocardial injuries, despite some sequence or location identity they share. Herein, we introduce the general differences of CB1 and CB2 cannabinoid receptors, and summarize the functional rivalries between the two brother receptors in the setting of myocardial injuries. We point out the importance of individual receptor-based modulation, instead of dual receptor modulators, when treating myocardial injuries.

[Antisense RNA mediated gene silencing of nonessential gene rpsF in Escherichia coli].

OBJECTIVE: We explored the cause of cell growth inhibition by antisense RNA mediated nonessential gene silencing of rpsF gene in Escherichia coli. METHODS: The 41 -230 bp fragment around 5' end of gene rpsF was reversely cloned into antisense expression vector pHN678, which is flanked with a paired-termini. The recombinant plasmid was named pHNF. Then it was transformed into E. coli to produce antisense RNA strain E. coli/pHNF. Antisense RNA expression was induced by isopropyl-beta-D-thiogalactopyranoside (IPTG), the difference of liquid growth phenotype was identified between E. coli/pHNF and the control strain E. coli/pHN678; and gene transcriptional level was measured by Real time RT-PCR. RESULTS: We obtained one antisense RNA strain targeted rpsF. We found that the reduced growth rate of this strain was positively related to the IPTG concentration. When IPTG was 100 micromol/L, the cell growth was not inhibited whereas the mRNA amount of rpsF had decreased by 36%, and mRNA of essential gene rpsR in the same operon did not decayed. However, when IPTG reached 200 micromol/L, the cell growth was obviously inhibited and rpsR mRNA was reduced by 12%. CONCLUSION: The essential gene transcription level of rpsR decreases with the nonessential gene silencing of rpsF in the same operon, and leads to the growth inhibition of E. coli/pHNF.

Hypoxic Exosomal circPLEKHM1-Mediated Crosstalk between Tumor Cells and Macrophages Drives Lung Cancer Metastasis.

Intercellular communication often relies on exosomes as messengers and is critical for cancer metastasis in hypoxic tumor microenvironment. Some circular RNAs (circRNAs) are enriched in cancer cell-derived exosomes, but little is known about their ability to regulate intercellular communication and cancer metastasis. Here, by systematically analyzing exosomes secreted by non-small cell lung cancer (NSCLC) cells, a hypoxia-induced exosomal circPLEKHM1 is identified that drives NSCLC metastasis through polarizing macrophages toward to M2 type. Mechanistically, exosomal circPLEKHM1 promoted PABPC1-eIF4G interaction to facilitate the translation of the oncostatin M receptor (OSMR), thereby promoting macrophage polarization for cancer metastasis. Importantly, circPLEKHM1-targeted therapy significantly reduces NSCLC metastasis in vivo. circPLEKHM1 serves as a prognostic biomarker for metastasis and poor survival in NSCLC patients. This study unveils a new circRNA-mediated mechanism underlying how cancer cells crosstalk with macrophages within the hypoxic tumor microenvironment to promote metastasis, highlighting the importance of exosomal circPLEKHM1 as a prognostic biomarker and therapeutic target for lung cancer metastasis.

Medication overdose data analysis: a review of medication error reports in the FDA adverse event reporting system (FAERS).

BACKGROUND: drug overdose is a common type of medication error, which caused significant patient injuries and economic losses. To determine which drugs are reported most frequently in association with drug overdose, a comprehensive search was conducted in the FDA Adverse Event Reporting System (FAERS) database. The study also sought to determine the top 10 drugs reported with drug overdose. METHODS: FAERS database was searched for drug overdose records submitted from the first quarter of 2017 to the fourth quarter of 2021. Descriptive analyses were conducted based on the total counts and percentages of reports associated with the drug. Subgroup analyses were performed on drugs of different pharmacological classifications. RESULTS: A total of 170,424 drug overdose reports were retrieved. The results revealed that antipyretics and analgesics took the highest risk for overdose, with 63,143 (37.05%) cases reported. Among them, opioids were associated with the most drug overdose events. The top 10 drug classes relating to drug overdose in FAERS were opioid analgesic, anilide antipyretic analgesic, 5-HT reuptake inhibitors, bronchodilators, monoclonal antibodies and antibody-drug conjugates, benzodiazepines, antipsychotics, GABA derivatives, antimanic agents, and propionic acid derivatives. CONCLUSION: to reduce the occurrence of drug overdose events, some methods could be considered including applying a pre-prescription review system, drug safety education, developing warning lists, etc.

Identification of electroporation sites in the complex lipid organization of the plasma membrane.

The plasma membrane of a biological cell is a complex assembly of lipids and membrane proteins, which tightly regulate transmembrane transport. When a cell is exposed to strong electric field, the membrane integrity becomes transiently disrupted by formation of transmembrane pores. This phenomenon termed electroporation is already utilized in many rapidly developing applications in medicine including gene therapy, cancer treatment, and treatment of cardiac arrhythmias. However, the molecular mechanisms of electroporation are not yet sufficiently well understood; in particular, it is unclear where exactly pores form in the complex organization of the plasma membrane. In this study, we combine coarse-grained molecular dynamics simulations, machine learning methods, and Bayesian survival analysis to identify how formation of pores depends on the local lipid organization. We show that pores do not form homogeneously across the membrane, but colocalize with domains that have specific features, the most important being high density of polyunsaturated lipids. We further show that knowing the lipid organization is sufficient to reliably predict poration sites with machine learning. Additionally, by analysing poration kinetics with Bayesian survival analysis we show that poration does not depend solely on local lipid arrangement, but also on membrane mechanical properties and the polarity of the electric field. Finally, we discuss how the combination of atomistic and coarse-grained molecular dynamics simulations, machine learning methods, and Bayesian survival analysis can guide the design of future experiments and help us to develop an accurate description of plasma membrane electroporation on the whole-cell level. Achieving this will allow us to shift the optimization of electroporation applications from blind trial-and-error approaches to mechanistic-driven design.

Cardiotoxicity of current antipsychotics: Newer antipsychotics or adjunct therapy?

Use of newer antipsychotics for substitution of current antipsychotics might be one way awaiting to be clinically verified to address antipsychotic cardiotoxic effects. Alternatively, the combination of existing antipsychotics with cardioprotective agents is also beneficial for patients with mental disorders for avoiding cardiotoxicity to the maximum.

Use of potassium ion channel and spliceosome proteins as diagnostic biomarkers for sudden unexplained death in schizophrenia.

Sudden unexplained death in schizophrenia (SUD-SCZ) is not uncommon and its incidence is approximately three times higher than that in the general population. However, diagnosis of SUD-SCZ remains a great challenge in forensic pathology. This study designed a two-phase study to investigate whether three proteins, namely two potassium ion channel proteins (KCNJ3 and KCNAB1) and one spliceosome protein (SF3B3) that were identified in our previous work, could be applied in the postmortem diagnosis of SUD-SCZ. Immunohistochemical staining of the three biomarkers, followed by a rigorous quantitative analysis, was performed on heart specimens from both SUD-SCZ and control groups. A diagnostic software based on the logistic regression formula derived from the test phase data was then constructed. In the test phase, we found that the staining intensities of KCNJ3, KCNAB1, and SF3B3 were all significantly lower in the SUD-SCZ group (n = 20) as compared with the control group that died from non-natural causes (n = 25), with fold-changes being 14.85 (p < 0.001), 4.13 (p = 0.028) and 2.12 (p = 0.048), respectively. Receiver operating characteristic analysis further illustrated that combination of the three biomarkers achieved the optimal diagnostic specificity (92%) and area under the curve (0.886). In the validation phase, the diagnostic software was confirmed to be a promising tool for predicting the risk of SUD-SCZ in authentic cases. Our study provided a valid strategy towards the practical diagnosis of SUD-SCZ by using KCNJ3, KCNAB1, and SF3B3 proteins as diagnostic biomarkers.

Valosin Containing Protein as a Specific Biomarker for Predicting the Development of Acute Coronary Syndrome and Its Complication.

Background: Acute coronary syndrome (ACS) consists of a range of acute myocardial ischemia-related manifestations. The adverse events of ACS are usually associated with ventricular dysfunction (VD), which could finally develop to heart failure. Currently, there is no satisfactory indicator that could specifically predict the development of ACS and its prognosis. Valosin-containing protein (VCP) has recently been proposed to protect against cardiac diseases. Hence, we aimed to assess whether VCP in serum can serve as a valuable biomarker for predicting ACS and its complication. Methods: Human serum samples from 291 participants were collected and classified into four groups based on their clinical diagnosis, namely healthy control (n = 64), ACS (n = 40), chronic coronary syndrome (CCS, n = 99), and nonischemic heart disease (non-IHD, n = 88). Clinical characteristics of these participants were recorded and their serum VCP levels were detected by enzyme-linked immunosorbent assay (ELISA). Association of serum VCP with the development of ACS and its complication VD was statistically studied. Subsequently, GWAS and eQTL analyses were performed to explore the association between VCP polymorphism and monocyte count. A stability test was also performed to investigate whether VCP is a stable biomarker. Results: Serum VCP levels were significantly higher in the ACS group compared with the rest groups. Besides, the VCP levels of patients with ACS with VD were significantly lower compared to those without VD. Multivariate logistic regression analysis revealed that VCP was associated with both the risk of ACS (P = 0.042, OR = 1.222) and the risk of developing VD in patients with ACS (P = 0.035, OR = 0.513) independently. The GWAS analysis also identified an association between VCP polymorphism (rs684562) and monocyte count, whereas the influence of rs684562 on VCP mRNA expression level was further verified by eQTL analysis. Moreover, a high stability of serum VCP content was observed under different preservation circumstances. Conclusion: Valosin-containing protein could act as a stable biomarker in predicting the development of ACS and its complication VD.

CB1R-stabilized NLRP3 inflammasome drives antipsychotics cardiotoxicity.

Long-term use of antipsychotics is a common cause of myocardial injury and even sudden cardiac deaths that often lead to drug withdrawn or discontinuation. Mechanisms underlying antipsychotics cardiotoxicity remain largely unknown. Herein we performed RNA sequencing and found that NLRP3 inflammasome-mediated pyroptosis contributed predominantly to multiple antipsychotics cardiotoxicity. Pyroptosis-based small-molecule compound screen identified cannabinoid receptor 1 (CB1R) as an upstream regulator of the NLRP3 inflammasome. Mechanistically, antipsychotics competitively bond to the CB1R and led to CB1R translocation to the cytoplasm, where CB1R directly interacted with NLRP3 inflammasome via amino acid residues 177-209, rendering stabilization of the inflammasome. Knockout of Cb1r significantly alleviated antipsychotic-induced cardiomyocyte pyroptosis and cardiotoxicity. Multi-organ-based investigation revealed no additional toxicity of newer CB1R antagonists. In authentic human cases, the expression of CB1R and NLRP3 inflammasome positively correlated with antipsychotics-induced cardiotoxicity. These results suggest that CB1R is a potent regulator of the NLRP3 inflammsome-mediated pyroptosis and small-molecule inhibitors targeting the CB1R/NLRP3 signaling represent attractive approaches to rescue cardiac side effects of antipsychotics.

Antipsychotics cardiotoxicity: What's known and what's next.

Chronic use of antipsychotic medications entails a dilemma between the benefit of alleviating psychotic symptoms and the risk of troubling, sometimes life-shortening adverse effects. Antipsychotic-induced cardiotoxicity is one of the most life-threatening adverse effects that raises widespread concerns. These cardiotoxic effects range from arrhythmia to heart failure in the clinic, with myocarditis/cardiomyopathy, ischemic injuries, and unexplained cardiac lesions as the pathological bases. Multiple mechanisms have been proposed to underlie antipsychotic cardiotoxicity. This review aims to summarize the clinical signs and pathological changes of antipsychotic cardiotoxicity and introduce recent progress in understanding the underlying mechanisms at both the subcellular organelle level and the molecular level. We also provide an up-to-date perspective on future clinical monitoring and therapeutic strategies for antipsychotic cardiotoxicity. We propose that third-generation antipsychotics or drug adjuvant therapy, such as cannabinoid receptor modulators that confer dual benefits - i.e., alleviating cardiotoxicity and improving metabolic disorders - deserve further clinical evaluation and marketing.

Equipment design and performance characterization of full field x-ray fluorescence (FF-XRF) element distribution imaging system with combined collimating lens (CCL).

This work describes a full field x-ray fluorescence element distribution imaging system with a combined collimating lens (CCL), which is more suitable for a higher x-ray energy range (12 keV-30 keV). The system consists of an optical-use charge-coupled device (CCD) camera coupled to a combined collimating lens (CCL), which includes pinhole collimator and x-ray window, x-ray tube, and sample room. The continuously variable magnification of 0.5-2 is achieved under a compact structure. The x-ray spectrum and two-dimensional element distribution mapping of the irradiated sample are obtained by processing a series of images acquired by using the CCD camera in a single photon counting mode. The energy resolution is 275 eV at the reference energy of 14.957 keV (yttrium Kα, Z = 39). The limit of detection is 46.41 ppm by measuring yttrium standard solution. The spatial resolution is 135 µm when using a 100 µm pinhole at the magnification of 1. Samples made by metal foils and mineral pigments are tested, and the results proved that the system was reliable when detecting elements of a high atomic number.