Role of microRNA 690 in Mediating Angiotensin II Effects on Inflammation and Endoplasmic Reticulum Stress
CELLS
Authors: Menikdiwela, Kalhara R.; Ramalingam, Latha; Abbas, Mostafa M.; Bensmail, Halima; Scoggin, Shane; Kalupahana, Nishan S.; Palat, Asha; Gunaratne, Preethi; Moustaid-Moussa, Naima
Abstract
Overactivation of the renin-angiotensin system (RAS) during obesity disrupts adipocyte metabolic homeostasis and induces endoplasmic reticulum (ER) stress and inflammation; however, underlying mechanisms are not well known. We propose that overexpression of angiotensinogen (Agt), the precursor protein of RAS in adipose tissue or treatment of adipocytes with Angiotensin II (Ang II), RAS bioactive hormone, alters specific microRNAs (miRNA), that target ER stress and inflammation leading to adipocyte dysfunction. Epididymal white adipose tissue (WAT) from B6 wild type (Wt) and transgenic male mice overexpressing Agt (Agt-Tg) in adipose tissue and adipocytes treated with Ang II were used. Small RNA sequencing and microarray in WAT identified differentially expressed miRNAs and genes, out of which miR-690 and mitogen-activated protein kinase kinase 3 (MAP2K3) were validated as significantly up- and down-regulated, respectively, in Agt-Tg, and in Ang II-treated adipocytes compared to respective controls. Additionally, the direct regulatory role of miR-690 on MAP2K3 was confirmed using mimic, inhibitors and dual-luciferase reporter assay. Downstream protein targets of MAP2K3 which include p38, NF-kappa B, IL-6 and CHOP were all reduced. These results indicate a critical post-transcriptional role for miR-690 in inflammation and ER stress. In conclusion, miR-690 plays a protective function and could be a useful target to reduce obesity.
Linc02381 Exacerbates Rheumatoid Arthritis Through Adsorbing miR-590-5p and Activating the Mitogen-Activated Protein Kinase Signaling Pathway in Rheumatoid arthritis-fibroblast-like synoviocytes
CELL TRANSPLANTATION
Authors: Wang, Jing; Zhao, Qing
Abstract
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease. New evidence suggested that linc02381 suppressed colorectal cancer progression by regulating PI3 K signaling pathway, but the role of linc02381 in other diseases, such as RA, remains unclear. This study aimed to reveal the mechanism of linc02381 in RA progression. In vivo and in vitro, we found that linc02381 was upregulated in RA synovial tissues or RA fibroblast-like synoviocytes (RA-FLSs, P < 0.01), which were detected by quantitative real-time polymerase chain reaction. Cell Counting Kit-8, EDU, and Transwell assays revealed that linc02381 overexpression enhanced cell proliferation and invasion, and linc02381 knockdown inhibited cell proliferation and invasion in FLSs. Moreover, the results of bioinformatics analysis, luciferase reporter gene assay, and pull-down assay verified that linc02381 could directly bind with miR-590-5p. MiR-590-5p was downregulated in RA-FLSs, and overexpression of linc02381 suppressed expression of miR-590-5p that post-transcriptionally suppressed the expression of mitogen-activated protein kinase kinase 3 (MAP2K3), and overexpression of miR-590-5p reversed the effect of linc02381 overexpression on MAP2K3 expression. MiR-590-5p inhibitor reversed the inhibition effect of linc02381 knockdown on proliferation and invasion of FLSs, which enhanced expression of MAP2K3, and activation of p38 and AP-1 in the MAPK signaling pathway. In summary, linc02381 was upregulated in RA synovial tissues and RA-FLSs, and it exacerbated RA by adsorbing miR-590-5p to activate the MAPK signaling pathway.