Diversity of arterial cell and phenotypic heterogeneity induced by high-fat and high-cholesterol diet.

Lipid metabolism disorder is the basis of atherosclerotic lesions, in which cholesterol and low-density lipoprotein (LDL) is the main factor involved with the atherosclerotic development. A high-fat and high-cholesterol diet can lead to this disorder in the human body, thus accelerating the process of disease. The development of single-cell RNA sequencing in recent years has opened the possibility to unbiasedly map cellular heterogeneity with high throughput and high resolution; alterations mediated by a high-fat and high-cholesterol diet at the single-cell transcriptomic level can be explored with this mean afterward. We assessed the aortic arch of 16-week old Apoe-/- mice of two control groups (12 weeks of chow diet) and two HFD groups (12 weeks of high fat, high cholesterol diet) to process single-cell suspension and use single-cell RNA sequencing to anatomize the transcripts of 5,416 cells from the control group and 2,739 from the HFD group. Through unsupervised clustering, 14 cell types were divided and defined. Among these cells, the cellular heterogeneity exhibited in endothelial cells and immune cells is the most prominent. Subsequent screening delineated ten endothelial cell subsets with various function based on gene expression profiling. The distribution of endothelial cells and immune cells differs significantly between the control group versus the HFD one. The existence of pathways that inhibit atherosclerosis was found in both dysfunctional endothelial cells and foam cells. Our data provide a comprehensive transcriptional landscape of aortic arch cells and unravel the cellular heterogeneity brought by a high-fat and high-cholesterol diet. All these findings open new perspectives at the transcriptomic level to studying the pathology of atherosclerosis.

METTL3-Mediated m6A RNA Modification Regulates Corneal Injury Repair.

Limbal stem cells are essential for continuous corneal regeneration and injury repair. METTL3-catalyzed N6-methyladenosine (m6A) mRNA modifications are involved in many biological processes and play a specific role in stem cell regeneration, while the role of m6A modifications in corneal injury repair remains unknown. In this study, we generated a limbal stem cell-specific METTL3 knockout mouse model and studied the role of m6A in repairing corneal injury caused by alkali burn. The results showed that METTL3 knockout in the limbal stem cells promotes the in vivo cell proliferation and migration, leading to the fast repair of corneal injury. In addition, m6A modification profiling identified stem cell regulatory factors AHNAK and DDIT4 as m6A targets. Our study reveals the essential functions of m6A RNA modification in regulating injury repair and provides novel insights for clinical therapy of corneal diseases.

Antibody-dependent enhancement of coronavirus.

Antibody-dependent enhancement (ADE) exists in several kinds of virus. It has a negative influence on antibody therapy for viral infection. This effect was first identified in dengue virus and has since also been described for coronavirus. To date, the rapid spread of the newly emerged coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), has affected over 3.8 million people across the globe. The novel coronavirus poses a great challenge and has caused a wave of panic. In this review, antibody-dependent enhancements in dengue virus and two kinds of coronavirus are summarized. Possible solutions for the effects are reported. We also speculate that ADE may exist in SARS-CoV-2.

Characteristics of the Coronavirus Disease 2019 and related Therapeutic Options.

The coronavirus disease 2019 (COVID-19) is a new type of pneumonia caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. COVID-19 is affecting millions of patients, and the infected number keeps increasing. SARS-CoV-2 is highly infectious, has a long incubation period, and causes a relatively high death rate, resulting in severe health problems all over the world. Currently there is no effective proven drug for the treatment of COVID-19; therefore, development of effective therapeutic drugs to suppress SARS-CoV-2 infection is urgently needed. In this review, we first summarize the structure and genome features of SARS-CoV-2 and introduce its infection and replication process. Then, we review the clinical symptoms, diagnosis, and treatment options of COVID-19 patients. We further discuss the potential molecular targets and drug development strategies for treatment of the emerging COVID-19. Finally, we summarize clinical trials of some potential therapeutic drugs and the results of vaccine development. This review provides some insights for the treatment of COVID-19.

Long Noncoding RNA HOXA-AS3 Integrates NF-κB Signaling To Regulate Endothelium Inflammation.

The long noncoding RNA HOXA-AS3 has recently been reported to act as a critical regulator in inflammation-linked lung adenocarcinoma. However, the roles of HOXA-AS3 in endothelium inflammation and related vascular disorders remain poorly defined. In the current study, we identified HOXA-AS3 to be a critical activator to promote NF-κB-mediated endothelium inflammation. HOXA-AS3, a chromatin-associated regulator which colocalizes with NF-κB at specific gene promoters, was found to interact with NF-κB and positively regulate its activity through control of the expression of the NF-κB inhibitor protein IκBα and the acetylation status at the K310 site of p65. More importantly, clinicopathological analysis showed that HOXA-AS3 expression has a significant positive correlation with atherosclerosis. Thus, we conclude that HOXA-AS3 may serve as a crucial biomarker for the clinical diagnosis of atherosclerosis, as well as a promising therapeutic target for the treatment of multiple inflammatory vascular diseases. In addition, this study suggests the functional importance of HOXA-AS3 in the regulation of inflammatory disorders.