MiR-146a-5p accelerates sepsis through dendritic cell activation and glycolysis via targeting ATG7

To unveil the role and regulatory mechanism of miR-146a-5p in sepsis. A sepsis cell model was established via lipopolysaccharide (LPS)-induction in dendritic cells (DCs). The maturation of DCs was evaluated via flow cytometry. Gene expression was measured through reverse-transcription quantitative polymerase chain reaction (RT-qPCR). The concentrations of inflammation biomarkers were revealed via enzyme-linked immunosorbent assay (ELISA). The pathological and histological changes in lungs in the sepsis mice model were analyzed via hematoxylin and eosin (H&E) staining. In this study, the miR-146a-5p level was elevated in the serum of sepsis patients and LPS-induced DCs but decreased in the serums of cured sepsis patients. Furthermore, miR-146a-5p deletion alleviated the activation of T cells and attenuated the imbalance of Th17/Treg. Besides, ATG7 was validated as a target of miR-146a-5p. ATG7 elevation enhanced lactate production and glucose uptake in LPS-triggered DCs. Additionally, upregulation of ATG7 suppressed the protein levels of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK), phospho protein kinase B (p-AKT), and phosphorylated signal transducer and activator for transcription 3 (p-STAT3). In addition, miR-146a-5p downregulation alleviated T-cell activation, inflammation, lactate production, and glucose uptake in sepsis mice. Moreover, the lung injury due to sepsis was also attenuated as a result of miR-146a-5p silencing. MiR-146a-5p aggravates sepsis through DCs activation and glycolysis via targeting ATG7.

miR-135a-5p mediated down-regulation of STAT6 inhibits proliferation and induces apoptosis of fibroblast-like synoviocytes in rheumatoid arthritis

OBJECTIVE

Rheumatoid arthritis (RA), as a chronic autoimmune disorder, seriously threatens human health. However, no study has thoroughly illustrated the etiology of RA. The present work focused on investigating the biological functions of STAT6 and the upstream miRNAs that regulate its expression.

METHODS

Synovial tissues from rheumatoid arthritis (RA) patients and normal participants were acquired. Cell viability, proliferation, apoptosis, concentrations of cytokines, miRNA and protein levels, and relative luciferase activities were detected.

RESULTS

WB and qRT-PCR showed that STAT6 was obviously up-regulated in synovial tissues of RA patients as well as RA fibroblast-like synoviocytes (RA FLSs). Functionally, down-regulation of STAT6 significantly inhibited the growth of RA FLSs as indicated by EdU and CCK-8 assays. In addition, inhibition of STAT6 remarkably promoted apoptosis of RA FLSs. Besides, silence of STAT6 notably suppressed inflammatory cytokine levels, such as TNF-α, IL-6 and IL-1β. Mechanistically, STAT6 was predicted to be the direct target of and negatively regulated by miR-135a-5p. Moreover, STAT6 was involved in the regulation of miR-135a-5p on cell growth, apoptosis and inflammatory response of RA FLSs.

CONCLUSION

miR-135a-5p/STAT6 is a potential novel therapeutic target for RA treatment.

miR-371b-5p-Engineered Exosomes Enhances Tumor Inhibitory Effect

Background: Exosomes are well-known natural nanovesicles, that represent one of the recently discovered modes of intercellular communication due to their ability to transmit cellular components. Exosomes have been reported to have potential as natural vectors for carrying functional small RNAs and delivering chemotherapeutic agents to diseased cells. In this study, we aimed to investigate the role of exosomes in carrying miRNA for targeting tumor cells.

Methods: We present a novel method for engineering exosomes with functional miR-317b-5b to target tumor cells. MiR-317b-5b exerts its anti-tumor function via its expression in tumors. RT-qPCR was performed to assess the levels of miR-371b-5p, FUT-4. Western blot was performed to measure the levels of CD9, CD81, and FUT-4 proteins. Confocal microscopy was used to observe the internalization of miR-317b-5b in tumor cells. CCK-8, EdU, flow cytometry, wound-healing migration and transwell assays were performed to evaluate cell viability, proliferation, migration, and invasion, respectively.

Results: Our findings illustrated that miR-317b-5b-loaded engineered exosomes were internalized by tumor cells. MiR-317b-5b was overexpressed in tumor cells treated with miR-317b-5b-loaded engineered exosomes. The internalization of miR-317b-5b in tumor cells was accompanied by changes of cell viability, proliferation, apoptosis, and migratory and invasive capability. We found that miR-317b-5b-loaded engineered exosomes were presence in tumor tissue sections and miR-317b-5b was overexpressed in tumor tissues of osteosarcoma tumor-bearing mice infected with miR-317b-5b-loaded engineered exosomes. MiR-317b-5b-loaded engineered exosomes had the anti-tumor efficiency in vivo.

Conclusion: Our findings show that miR-317b-5b-loaded engineered exosomes can be used as nanocarriers to deliver drug molecules such as miR-317b-5b both in vitro and in vivo to exert its anti-tumor functions.

miR-21-5p inhibits inflammation injuries in LPS-treated H9c2 cells by regulating PDCD4

OBJECTIVES

To explore the expression levels and the potential regulatory mechanism of miR-21-5p in LPS-treated H9c2 cells.

METHODS

The secretions of the inflammatory cytokines induced by LPS in H9c2 cells were evaluated using ELISA. We used RT-RCR and western blot to measure the relative mRNA and protein expression levels in LPS-treated H9c2 cells. CCK-8 and EdU assays showed the viability and proliferation profiles of the H9c2 cells. TUNEL assays demonstrated the apoptotic behaviors of the H9c2 cells, and a luciferase reporter analysis was used to investigate the interactions between miR-21-5p and programmed cell death protein 4 (PDCD4).

RESULTS

LPS induced damage to the H9c2 cells by reducing the cell viability and down-regulating miR-21-5p. On the other hand, miR-21-5p overexpression inhibited the LPS-induced inflammatory damage in the H9c2 cells. Moreover, PDCD4 was verified as a downstream target gene of miR-21-5p, and its expression was inhibited by the higher miR-21-5p content. Finally, miR-21-5p inhibited septic processes, and the PDCD4 overexpression rescued the miR-21-5p effect in the LPS-treated H9c2 cells.

CONCLUSION

Our findings suggest that miR-21-5p inhibits the LPS-induced progression of sepsis in H9c2 cells. Additionally, PDCD4 is a downstream target gene of miR-21-5p, and both molecules serve as potential therapeutic targets for heart sepsis patients.

LncRNA NEAT1 Promotes Inflammatory Response in Sepsis via the miR-31-5p/POU2F1 Axis

Sepsis is considered to be a systemic inflammatory response, which results in organ dysfunction. LncRNA nuclear-enriched abundant transcript 1 (NEAT1) involved in sepsis progression has been reported. However, the underlying mechanism of NEAT1 in sepsis-induced inflammatory response remains to be revealed. In this study, NEAT1 and POU domain class 2 transcription factor 1 (POU2F1) were highly expressed in LPS-induced septic RAW264.7 cells, opposite to miR-31-5p expression. Furthermore, we found that NEAT1 silencing inhibited LPS-induced inflammatory response and cell proliferation, and promoted cell apoptosis. Subsequently, we found that miR-31-5p interacted with NEAT1 and targeted the 3'UTR of POU2F1, and in LPS-induced RAW264.7 cells, the inhibition of NEAT1 silencing was reversed by miR-31-5p knockdown, while POU2F1 downregulation could cover the functions of miR-31-5p knockdown. In a word, this study indicates that NEAT1 inhibits the LPS-induced progression of sepsis in RAW264.7 cells by modulating miR-31-5p/POU2F1 axis, suggesting that NEAT1 will be the potential therapeutic target for sepsis.

AB0046 THE EXPRESSION AND CLINICAL SIGNIFICANCE OF TAM RECEPTOR TYROSINE KINASE ON MONOCYTE SUBSETS IN RHEUMATOID ARTHRITIS

Background:

The TAM receptor tyrosine kinases (Tyro3/Axl/Mer TK) are a subfamily of receptor tyrosine kinases, the role of which in autoimmune diseases such as systemic lupus erythematosus has been well explored, while their functions in rheumatoid arthritis (RA) remain largely unknown [1].

Objectives:

The study aimed to investigate the expression and clinical significance of Tyro3, Axl and MerTK on monocyte subsets in rheumatoid arthritis (RA).

Methods:

The expression of Tyro3, Axl and MerTK on CD14+ monocytes, nonclassical monocytes (NCM, CD14+CD16++), intermediate monocytes (IM, CD14++CD16+), and classical monocytes (CM, CD14++CD16-) were evaluated in peripheral blood of RA by flow cytometry and qPCR. And the correlation between the expression of Tyro3TK and MerTK on NCM, IM, and CM with RA patient clinical feature were further analyzed.

Results:

The results revealed that the expression of Tyro3TK on CD14+ monocytes was significantly upregulated in RA patients (F = 9.18, P < 0.0001), while there was no significant difference of the expression MerTK on HC, OA, and RA, and the expression of AxlTK was minimal (Fig 1). The expression of Tyro3TK on CM was significantly upregulated in RA patients as compared with HC and osteoarthritis (OA) patients (P < 0.05, Fig 2-3), and positively correlated with the disease manifestations, such as swollen joint count (SJC), tender joint count (TJC) and the disease activity score (Fig 4).

Figure 1.

The expression of Tyro3, Axl and MerTK on CD14+ monocytes is increased in RA. (a) Gating strategy for flow cytometry of Tyro3, Axl and MerTK on CD14+ monocytes. (b) The expression of Tyro3, Axl and MerTK on CD14+ monocytes were compared between HC (n = 40), OA (n = 27), and RA patients (n = 40). *P < 0.05, **P < 0.01, ns, not significant.

Figure 2.

The expression of Tyro3TK on IM and CM were increased in RA. (a) Gating strategy for flow cytometry of TAMTK on monocyte subsets. The expression of (b) Tyro3TK and (c) MerTK on NCM, IM, and CM were compared between HC (n = 40), OA (n = 27), and RA patients (n = 40). *P < 0.05, **P < 0.01, ***P < 0.001, ns, not significant.

Figure 3.

The mRNA expression of Tyro3TK on CM is increased in RA. (a) The mRNA expression of Tyro3TK on NCM, IM, and CM in HC (n = 3) and RA (n = 3) patients. (b) The mRNA expression of MerTK on NCM, IM, and CM in HC (n = 3) and RA (n = 3) patients. **P < 0.01.

Conclusion:

These findings indicate that Tyro3TK on CM was elevated in RA patients and correlated positively with disease activity, which may serves as an important participant in RA pathogenesis.

References:

[1]Rothlin CV, Lemke G, TAM receptor signaling and autoimmune disease. Curr Opin Immunol, 2010. 22(6): p. 740-6.

Footnotes:

The study was supported by grants from the National Natural Science Foundation of China (81671609 and 81871290 to Dr. Y. Su, 82001718 to Dr. L. Xu), the Beijing Science and Technology Planning Project (Z191100006619111 to Dr. Y. Su), the Beijing Municipal Natural Science Foundation (7194329 to Dr. L. Xu).

Figure 4.

Correlation analysis of Tyro3TK on IM and CM with RA patient clinical manifestations. The associations of Tyro3TK on IM (r = 0.492, *P = 0.001) (a) and CM (r = 0.577, *P = 0.0001) (b) with RA patient swollen joint counts (SJC) were analyzed, respectively. The expression of Tyro3TK on IM and CM were also compared between different RA patient groups: (c) RA with high disease activity (DAS28-ESR > 3.2) and non-high disease activity (DAS28-ESR ≤ 3.2), (d) RA with and without swollen joints, (e) tender joints. *P < 0.05, **P < 0.01.

Disclosure of Interests:

None declared

AB0564 RHEUMATOLOGISTS’ VIEWS AND EXPERIENCES IN MANAGING PsA PATIENTS BASED ON TREATING TO TARGET STRATEGY: A CROSS-SECTIONAL STUDY IN CHINA

Background:

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis with progressive, erosive destruction associated with functional impairment. Principles of treat-to-target (T2T) have been widely used in rheumatoid arthritis, which has powerfully improved patient outcomes. In 2017, the concept of T2T has proposed to apply in PsA patients. However, the awareness and implementation of evidence-based T2T treatment guidelines varies across different geographical regions of China, hospital grades, professional status and specialities.

Objectives:

The study aimed to investigate Rheumatologists’ views and experiences in managing PsA patients with T2T strategy in china.

Methods:

A cross-sectional questionnaire survey of Rheumatologists in China from 5 August to 15 August 2020 was conducted for this study. Rheumatologists were contacted by WeChat (a Chinese cell/web app) and asked to complete a web-based questionnaire anonymously. The electronic questionnaire was sent out by the internet platform of WenJuanXing via WeChat (https://www.wjx.cn/). The questionnaire was designed to collect: (a) demographic information; (b) patient management in clinical practice for Rheumatologists; (c) familiarity and application of T2T strategy in Rheumatologists. P values ≤0.05 were considered significant.

Results:

(1) A total of 823 rheumatologists (69.87% female, 30.13% male) provided valid answers to the questionnaire. 71.09% of the participants major in Modern Western Medicine, 28.91% major in traditional chinese medicine. A total of 75.94% worked in Grade-A Tertiary Hospital. A total of 52.73% had more than 10 years of work experience and 63.55% had High-level title. (2) More than half of the patients were followed up by 69% Rheumatologists in their daily practice. The proportion of follow-up patients increased powerfully in the group of Rheumatologists who major in Modern Western Medicine (P=0.014), work in Grade-A Tertiary Hospital (P<0.001), have more than 10 years of work experience (P<0.001) and High-level title (P<0.001). (3) 36.45% Rheumatologist thought the frequency for patient disease activity assessment was every 1 month and 53.1% was every 3 months. And 41.7% Rheumatologist prefer to use PASDAS for disease activity criteria, and only 3.6% choose MDA. (4) A total of 62.43% thought they were familiar with T2T strategy, and 83.6% Rheumatologists applied T2T strategy in clinical practice. Among 135 Rheumatologists who did not apply T2T strategy, 62.2% of Rheumatologists thought that the main barrier to T2T application was that they did not fully understand the strategy. The frequency of application of T2T strategy in clinical practice was significantly different between Rheumatologists who major in Modern Western Medicine (60.75%) and traditional chinese medicine (22.84%) (P=0.023).

Conclusion:

In china, the management of PsA patients need to be standardized to improve patient outcomes. And the promotion of T2T strategy in PsA need to be further strengthened.

References:

[1]Smolen JS, Schöls M, Braun J,et al. Treating axial spondyloarthritis and peripheral spondyloarthritis, especially psoriatic arthritis, to target: 2017 update of recommendations by an international task force. Ann Rheum Dis. 2018 Jan;77(1):3-17.

[2]Tucker LJ, Ye W, Coates LC. Novel Concepts in Psoriatic Arthritis Management: Can We Treat to Target? Curr Rheumatol Rep. 2018 Sep 18;20(11):71.

[3]Coates LC, Helliwell PS. Treating to target in psoriatic arthritis: how to implement in clinical practice. Ann Rheum Dis. 2016;75(4):640-643.

Figure 1

A. Rheumatologist priority of frequency for patient follow-up in different disease status. B. Rheumatologist priority of frequency for patient disease activity assessment in clinical practice. C. Rheumatologist priority of disease activity criteria for PsA patients.

Disclosure of Interests:

None declared.

Chemopreventive effect of galangin against benzo(a)pyrene-induced stomach tumorigenesis through modulating aryl hydrocarbon receptor in Swiss albino mice

The present study was aimed to evaluate the chemopreventive potential of galangin against benzo(a)pyrene (BaP)-induced stomach carcinogenesis in Swiss albino mice. Stomach cancer was induced in experimental mice using BaP oral administration. The mice were treated with galangin (10 mg/kg b.wt.) before and during BaP administration. Oral administration of galangin at a dose of 10 mg/kg b.wt. significantly (p < 0.05) prevented the tumor incidence, tumor volume in the experimental animals. Further, galangin pretreatment prevents BaP-induced lipid peroxidation and restores BaP-mediated loss of cellular antioxidants status. It has also been found that galangin prevents BaP-induced activation of phase I detoxification enzymes. Furthermore, galangin pretreatment prevented the BaP-induced overexpression of cytochrome P450s isoform genes (CYP1A1, CYP1B1), aryl hydrocarbon receptor system (AhR, ARNT), transcriptional activators (CBP/p300, NF-kB), tumor growth factors, proto-oncogenes, invasion markers (TGFB, SRC-1, MYC, iNOS, MMP2, MMP9) and Phase II metabolic isoenzyme genes (GST) in the stomach tissue homogenate when compared to the control groups. The western blot results confirm that galangin (10 mg/kg. b.wt.) treatment significantly prevented the BaP-mediated expression of ArR, ARNT, and CYP1A1 proteins in the mouse stomach tissue. Therefore, the present results confirm that galangin prevents BaP-induced stomach carcinogenesis probably through modulating ArR and ARNT expression in the experimental mice.

A human antibody of potent efficacy against SARS-CoV-2 in rhesus macaques showed strong blocking activity to B.1.351

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which causes coronavirus disease-2019 (COVID-19), interacts with the host cell receptor angiotensin-converting enzyme 2 (hACE2) via its spike 1 protein during infection. After the virus sequence was published, we identified two potent antibodies against the SARS-CoV-2 receptor binding domain (RBD) from antibody libraries using a phage-to-yeast (PtY) display platform in only 10 days. Our lead antibody JMB2002, now in a Phase 1 clinical trial (ChiCTR2100042150), showed broad-spectrum in vitro blocking activity against hACE2 binding to the RBD of multiple SARS-CoV-2 variants, including B.1.351 that was reportedly much more resistant to neutralization by convalescent plasma, vaccine sera and some clinical-stage neutralizing antibodies. Furthermore, JMB2002 has demonstrated complete prophylactic and potent therapeutic efficacy in a rhesus macaque disease model. Prophylactic and therapeutic countermeasure intervention of SARS-CoV-2 using JMB2002 would likely slow down the transmission of currently emerged SARS-CoV-2 variants and result in more efficient control of the COVID-19 pandemic.

[Role of institutional cultural building in the schistosomiasis control program of Jiangsu Province]

Jiangsu Province was once one of the provinces that are hyperendemic for schistosomiasis in China. Following the concerted efforts for nearly 70 years, the transmission of schistosomiasis was interrupted in the province in 2019, which is the first province to achieve the national criteria of interruption of schistosomiasis transmission among the 5 provinces locating in the marshland and lake regions. In addition to political, economic and scientific and technical factors that greatly contribute to the huge achievements from schistosomiasis control in Jiangsu Province, the spiritual implication of Jiangsu schistosomiasis control culture that is mainly characterized by dedication, rigorousness, truth-seeking and innovation play a vital role in the schistosomiasis control program of Jiangsu Province, which encourages generations of schistosomiasis control professionals working in Jiangsu Province to fight against the "God of plague".