LncRNA-GAS5 Inhibits Expression of miR 103 and Ameliorates the Articular Cartilage in Adjuvant-Induced Arthritis in Obese Mice

Xinfeng Capsule Inhibits Pyroptosis and Ameliorates Myocardial Injury in Rats with Adjuvant Arthritis via the GAS5/miR-21/TLR4 Axis

Purpose

This study probed the mechanism of action of Xinfeng Capsule (XFC) in myocardial injury in rats with adjuvant arthritis (AA) via the growth arrest-specific transcript 5 (GAS5)/microRNA-21 (miR-21)/Toll-like receptor 4 (TLR4) axis.

Methods

Rats were injected with Freund's complete adjuvant to establish a rat model of AA. Then, some modeled rats were given normal saline or drugs only, and some modeled rats were injected with adeno-associated viruses or necrosulfonamide (NSA; a pyroptosis inhibitor) before drug administration. Toe swelling and arthritis index (AI) were calculated. Pathological and morphological changes in synovial and myocardial tissues were analyzed with hematoxylin-eosin staining, and pyroptotic vesicles and the ultrastructural changes of myocardial tissues were observed with transmission electron microscopy. The serum levels of interleukin (IL)-1β, IL-18, IL-6, and tumor necrosis factor (TNF)-α were detected, and lactate dehydrogenase (LDH) release was measured in myocardial tissues, accompanied by the examination of GAS5, miR-21, TLR4, nuclear factor-kB (NF-κB) p65, nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), Caspase-1, and Gasdermin D (GSDMD) expression in myocardial tissues.

Results

After AA modeling, rats presented with significantly increased toe swelling and AI scores, synovial and myocardial tissue damage, elevated pyroptotic vesicles, and markedly enhanced serum levels of IL-1β, IL-18, IL-6, and TNF-α, accompanied by significantly diminished GAS5 expression, substantially augmented miR-21, TLR4, NF-κB p65, NLRP3, Caspase-1, and GSDMD expression, greatly increased LDH release in myocardial tissues. XFC treatment significantly declined toe swelling, AI scores, synovial and myocardial tissue damage, and the serum levels of IL-1β, IL-18, IL-6, and TNF-α in AA rats. Additionally, XFC treatment markedly elevated GAS5 expression and substantially lowered LDH release and miR-21, TLR4, NF-κB p65, NLRP3, Caspase-1, and GSDMD expression in myocardial tissues of AA rats. Moreover, the above effects of XFC in AA rats were further promoted by GAS5 overexpression or NSA treatment.

Conclusion

XFC alleviated myocardial injury in AA rats by regulating the GAS5/miR-21/TLR4 axis and inhibiting pyroptosis and pro-inflammatory cytokine secretion.

The effect of long non-coding RNAs in joint destruction of rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease accompanied with joint destruction. Serious joint destruction will eventually lead to disability and the decline of life quality in RA patients. At present, the therapeutic effect of drugs to alleviate joint destruction in RA is limited. Recently, accumulating evidences have shown that long non-coding RNAs (lncRNAs) play an important role in the pathogenesis of joint diseases. Therefore, this paper reviews the expression change and the action mechanism of lncRNAs in joint destruction of RA in recent years. A more comprehensive understanding of the role of lncRNAs in joint destruction will help the treatment of RA.

FGF/FGFR-related lncRNAs based classification predicts prognosis and guides therapy in gastric cancer

Fibroblast growth factor (FGF) and its receptor (FGFR) play crucial roles in gastric cancer (GC). Long non-coding RNAs (lncRNAs) are defined as RNA molecules of around 200 nucleotides or more, which are not translated into proteins. As well-known regulatory factors, lncRNAs are considered as biomarkers for prognosis and treatment response in GC. It is of importance to identify FGF/FGFR-related lncRNAs in GC. Here, some FGF/FGFR-related lncRNAs were identified in GC based on the data from public databases, the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Then a four-lncRNAs (FGF10-AS1, MIR2052HG, POU6F2-AS2, and DIRC1) risk score (RS) model was established for predicting GC’s prognosis by using Cox analysis. According to the median value of RS, GC patients were divided into low and high RS group. Low RS group displayed high tumor mutation burden and infiltration of immune cells, as well as more sensitivity to immunotherapy or chemotherapy. High RS group showed high infiltration of stromal cells and more oncogenic signatures. In addition, a comprehensive analysis was carried out and found that high RS group may exhibit specific sensitivity to Panobinostat (histone deacetylases inhibitor) and Tivantinib (MET inhibitor). In summary, our study not only offers a novel personalized prognostication classification model according to FGF/FGFR-related lncRNAs, but also provides a new strategy for subclass-specific precision treatment in GC.

YY1-induced lncRNA XIST inhibits cartilage differentiation of BMSCs by binding with TAF15 to stabilizing FUT1 expression

Introduction

The functional roles and mechanism of the XIST in osteoarthritis and the chondrogenic differentiation of BMSCs were clarified.

Methods

The expression levels of XIST, TAF15, FUT1 and YY1 were detected through quantitative RT-PCR. The protein expression of Sox9, ACAN, COL2A1 and FUT1 were detected by western blot and immunohistochemistry. The damage of cartilage tissue was detected by HE staining, and Safranin O-fast green. Alcian-Blue and Alizarin red S staining were performed to evaluate BMSCs chondrogenic differentiation. The relationship between XIST and TAF15, XIST and TAF15 were analyzed by RNA immunoprecipitation assay. Luciferase reporter assays and chromatin immunoprecipitation were performed to detect the interaction relationship between XIST and YY1. In addition, osteoarthritis mice were built to assess the function of XIST in vivo.

Results

The levels of XIST, TAF15 and FUT1 were upregulated in cartilage tissues from osteoarthritis patient. The level of XIST was decreased in BMSCs during chondrogenic differentiation. XIST overexpression inhibited the chondrogenic differentiation of BMSCs. Moreover, silencing of FUT1 reversed the effects of XIST overexpression on BMSCs chondrogenic differentiation. Mechanistically, in BMSCs, YY1 induced the expression of XIST in BMSCs, and XIST regulated FUT1 mRNA stability through targeting TAF15. Furthermore, silencing of XIST alleviated the symptoms of cartilage injury in OA mice.

Conclusion

Taken together, these results suggested that YY1 induced XIST was closely related to the chondrogenic differentiation of BMSCs and the progression of osteoarthritis by TAF15/FUT1 axis, and may be a new OA therapeutic target.

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XIST and TAF15 expression were upregulated in osteoarthritis.

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Overexpression of XIST suppressed the chondrogenic differentiation of BMSCs.

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XIST regulated BMSCs chondrogenic differentiation through enhancing FUT1 mRNA stability via TAF15.

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XIST silencing relieved cartilage damage in OA mice.

KLF4 downregulates FGF21 to activate inflammatory injury and oxidative stress of LPS‑induced ATDC5 cells via SIRT1/NF‑κB/p53 signaling

Ankylosing spondylitis (AS) is a chronic inflammatory disease. Transcriptional regulation of fibroblast growth factor 21 (FGF21) by the transcription factor Krüppel-like factor 4 (KLF4) serves an important role in chronic inflammatory disease. However, to the best of our knowledge, the role of both these factors in AS has not been previously reported. In the present study, ATDC5 cells were induced by lipopolysaccharide (LPS) to establish an AS inflammatory injury model. The expression levels of FGF21 and KLF4 were detected using reverse transcription-quantitative PCR and western blotting. Cell transfection was performed to alter the expression levels of KLF4 and FGF21. Subsequently, the regulatory effects and mechanisms underlying KLF4 and FGF21 on oxidative stress and inflammation in AS were investigated by performing Cell Counting Kit-8 assays, ELISAs, TUNEL staining and western blotting. Moreover, the expression levels of sirtuin 1 (SIRT1)/NF-κB/p53 pathway-related proteins were detected via western blotting. FGF21 overexpression promoted LPS-induced viability on ATDC5 cells, inhibited LPS-induced apoptosis, and decreased the LPS-induced inflammatory response and oxidative stress levels of ATDC5 cells. Overexpression of the transcription factor KLF4 reversed the protective effect of FGF21 overexpression on LPS-induced inflammatory injury in ATDC5 cells. The results suggested that this process may be achieved via regulating the SIRT1/NF-κB/p53 signaling pathway. Overall, the present study demonstrated that KLF4 downregulates FGF21 to activate inflammatory injury and oxidative stress of LPS-induced ATDC5 cells via SIRT1/NF-κB/p53 signaling.

Long noncoding RNA GAS5 in age-related diseases

Aging refers to a natural process and a universal phenomenon in all cells, tissues, organs and the whole organism. Long non-coding RNAs (lncRNAs) are non-coding RNAs with the length of 200 nucleotides. LncRNA growth arrest-specific 5 (lncRNA GAS5) is often down-regulated in cancer. The accumulation of lncRNA GAS5 has been found to be able to inhibit cancer growth, invasion and metastasis, while enhancing the sensitivity of cells to chemotherapy drugs. LncRNA GAS5 can be a signaling protein, which is specifically transcribed under different triggering conditions. Subsequently, it is involved in signal transmission in numerous pathways as a signal node. LncRNA GAS5, with a close relationship to multiple miRNAs, was suggested to be involved in the signaling pathway under three action modes (i.e., signal, bait and guidance). LncRNA GAS5 was found to be involved in different age-related diseases (e.g., rheumatoid arthritis, type 2 diabetes, atherosclerosis, osteoarthritis, osteoporosis, multiple sclerosis, cancer etc.). This study mainly summarized the regulatory effect exerted by lncRNA GAS5 on age-related diseases.