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Background: Atherosclerosis (AS) is a multifocal, smoldering immune inflammatory disease of medium and large arteries driven by lipids. The aim of this study is to discuss the mechanism of microRNA-146a-3p (miR-146a-3p)/histone deacetylase 1 (HDAC1)/Krüppel-like factor 5 (KLF5)/inhibitors of kappa B α (IKBα) signal axis in plaque formation of AS mice., Methods: ApoE -/- mice were fed with high-fat feed for 12 weeks to establish AS mice model. The expression of miR-146a-3p, KLF5, HDAC1 and IKBα in aortic wall tissues of AS mice was tested. The targeting relationship between miR-146a-3p and HDAC1 was verified. AS mice were injected with miR-146a-3p antagomir or HDAC1 overexpression to verify the impacts of miR-146a-3p and HDAC1 on blood lipids and inflammatory factors in serum, aortic wall apoptotic cells, antioxidant stress capacity and the plaque area in AS mice. VECs proliferation and apoptosis were also measured in vitro., Results: miR-146a-3p and KLF5 were increased while HDAC1 and IKBα were reduced in aortic wall tissues of AS mice. miR-146a-3p directly targeted to HDAC1. Depletion of miR-146a-3p or restoration of HDAC1 was correlated to lower plasma lipid level, reduced inflammatory factors in serum, attenuated aortic wall apoptosis, increased antioxidant stress capacity and improved the stability of pathological plaque of AS mice. miR-146a-3p down-regulation or HDAC1 up-regulation promoted VECs proliferation and inhibited apoptosis., Conclusion: Functional studies show that depleted miR-146a-3p advances HDAC1 and IKBα expression as well as inhibits KLF5 expression to facilitate the stability of pathological plaques in AS mice., (Copyright © 2021. Published by Elsevier Inc.)

Objective: The abnormal expression of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) has been demonstrated to exert pivotal effects in human diseases. We focused on the functions of metastasis associated lung adenocarcinoma transcript 1 (MALAT1) and microRNA let-7f on diabetic nephropathy (DN)., Methods: The diabetes (db/db) mice were treated with silenced MALAT1, then the baseline indicators, pathology changes, marker proteins of podocyte injury (nephrin, podocin, desmin and Cleaved caspase-3), oxidative stress indicators and inflammatory factors in renal tissues were determined. Murine podocyte MPC5 cells were stimulated by high glucose (HG) and transfected with sh-MALAT1 or let-7f mimic, then the cell migration, adhesion ability and apoptosis were evaluated. Moreover, the binding relationship between MALAT1 and let-7f, and the targeting relationship between let-7f and krüppel-like factor 5 (KLF5) were confirmed., Results: Silenced MALAT1 could improve baseline indicators of DN mice, and also improved pathology, increased nephrin and podocin expression, decreased desmin and Cleaved caspase-3 expression, and restrained oxidative stress and inflammatory reaction in their renal tissues. Additionally, elevated let-7f and reduced MALAT1 could restrict migration and apoptosis of HG-induced MPC5 cells, and promoted the cell adhesion ability., Conclusion: Results in our research indicated that the reduced MALAT1 could relieve the podocyte injury in DN by upregulating let-7f and inhibiting KLF5, which may be helpful for DN therapy., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The transcription factor Krüppel-like factor 5 (KLF5) is highly expressed in many cancers and serves as a prognostic factor. However, the function of KLF5 in hepatocellular carcinoma (HCC) is unclear. In this study, we found that KLF5 was significantly overexpressed in HCC cell lines and specimens, and high KLF5 expression predicted a poor prognosis for HCC patients. Then, we studied the effects of KLF5 on the proliferation, apoptosis, migration and invasion of HCC cells in vitro and vivo. The inhibition of KLF5 markedly inhibited HCC growth and metastasis, while KLF5 overexpression promoted these processes. In addition, we observed that KLF5 could promote the epithelial-mesenchymal transition (EMT) in HCC via the PI3K/AKT/Snail signaling pathway. The silencing of KLF5 in HCC cell lines downregulated the expression of N-cadherin, Vimentin and Snail and increased the expression of the epithelial marker E-cadherin. The expression of MMP2 and MMP9 was also decreased in KLF5-silenced HCC cells. However, opposite results were observed in the KLF5-overexpressing group. These results indicate that KLF5 plays a significant role in HCC progression and metastasis and induces EMT via activating PI3K/AKT/Snail signaling, and the inhibition of KLF5 may be a potential treatment modality for patients with HCC., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Intervertebral disc degeneration causes low back pain.Interleukin-1β (IL-1β) is a well-known inflammatory mediator that is involved in disc degeneration but its molecular mechanisms on catabolic and anabolic events in nucleus pulposus (NP) cells remain unclear. Krüppel-like factor 5 (KLF5) is associated with inflammation and was previously shown to cause cartilage degradation. In this study, we revealed that KLF5 is involved in IL-1β activated NF-kB cascade by enhancing both p65 phosphorylation and p65 acetylation. Moreover, the catabolic effect of KLF5 can be abolished by transforming growth factor-β (TGF-β) via promoting the proteasomal degradation of KLF5. Therefore, a KLF5 inhibitor ML264 was further proved to synergize with TGF-β to attenuate IL-1β-induced intervertebral disc degeneration. These results indicate the critical role of KLF5 in regulating intervertebral disc metabolism and suggest KLF5 inhibitor such as ML264 as potential compound for treatment of degenerative disc disease., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Unfractionated heparin (UFH) and low-molecular-weight heparins (LMWH), apart from anticoagulant activities, contain a variety of biological properties such as anti-inflammatory actions possibly affecting sepsis. Chemokines are vital for promoting the movement of circulating leukocytes to the site of infection and are involved in the pathogenesis of sepsis. The purpose of this study was to investigate the effects and potential mechanisms of UFH on lipopolysaccharide (LPS)-induced chemokine production in human pulmonary microvascular endothelial cells (HPMECs). HPMECs were pretreated with UFH (0.1 U/ml and 1 U/ml), 15 min prior to stimulation with LPS (10 μg/ml). Cells were cultured under various experimental conditions for 2 h and 6 h for analysis. UFH markedly decreased LPS-induced interleukin (IL)-8 and monocyte chemoattractant protein-1 (MCP-1) mRNA and protein expression in HPMECs. UFH also attenuated the secretion of these chemokines in culture supernatants. In addition, UFH blocked the chemotactic activities of LPS-stimulated HPMECs supernatants on monocytes migration as expected. UFH inhibited LPS-induced Krüppel-like factor 5 (KLF-5) mRNA and protein levels. Concurrently, UFH reduced nuclear factor (NF)-κB nuclear translocation. Importantly, transfection with siRNA targeting KLF-5 reduced NF-κB activation and chemokines expression. These results demonstrate that interfering with KLF-5 mediated NF-κB activation might contribute to the inhibitory effects of chemokines and monocytes migration by UFH in LPS-stimulated HPMECs., (Copyright © 2014 Elsevier GmbH. All rights reserved.)