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Pulmonary arterial hypertension (PAH) is a malignant cardiovascular disease. Eukaryotic initiation factor 2α (eIF2α) plays an important role in the proliferation of pulmonary artery smooth muscle cells (PASMCs) in hypoxia-induced pulmonary hypertension (HPH) rats. However, the regulatory mechanism of eIF2α remains poorly understood in PAH rats. Here, we discover eIF2α is markedly upregulated in monocrotaline (MCT)-induced PAH rats, eIF2α can be upregulated by mRNA methylation, and upregulated eIF2α can promote PASMC proliferation in MCT-PAH rats. GSK2606414, eIF2α inhibitor, can downregulate the expression of eIF2α and alleviate PASMC proliferation in MCT-PAH rats. And we further discover the mRNA of eIF2α has a common sequence with N 6-methyladenosine (m 6 A) modification by bioinformatics analysis, and the expression of METTL3, WTAP, and YTHDF1 is upregulated in MCT-PAH rats. These findings suggest a potentially novel mechanism by which eIF2α is upregulated by m 6 A modification in MCT-PAH rats, which is involved in the pathogenesis of PAH., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

This study is designed to investigate the effects of berberine (BBR) on galectin-3 (Gal-3) and the relationships to its suppressive activities on adipocyte differentiation, proliferation and adiposity. Our results showed that BBR greatly suppressed the differentiation and proliferation of mouse primary preadipocytes isolated from epididymal white adipose tissue (eWAT), during which the expression level of Gal-3 was down-regulated significantly. Overexpression of Gal-3 totally abolished the suppressive activities of BBR on Gal-3 expression, preadipocyte differentiation and proliferation. BBR reduced Gal-3 promoter activity, destabilized its mRNA and inhibited firefly luciferase activity of a recombinant plasmid containing the Gal-3 3' untranslated region (UTR). Furthermore, BBR up-regulated microRNA (miRNA) let-7d expression and the suppressive activity on Gal-3 3'UTR was abolished by point mutation on the let-7d binding site. In mice fed a high-fat diet (HFD), BBR up-regulated let-7d and down-regulated Gal-3 expression in eWAT; it also suppressed adipocyte differentiation and proliferation and reduced adiposity greatly. In summary, our study proves that BBR inhibits the differentiation and proliferation of adipocytes through down-regulating Gal-3, which is closely associated with its anti-obesity effect. Our results may support the future clinical application of BBR for the treatment of obesity or related diseases.

Background/aims: The aim of this study was to determine the anti-psoriasis effects of α-(8-quinolinoxy) zinc phthalocyanine (ZnPc-F7)-mediated photodynamic therapy (PDT) and to reveal its mechanisms., Methods: HaCaT cells were used to observe the influence of ZnPc-F7-PDT on cell proliferation in vitro. The in vivo anti-psoriasis effects of ZnPc-F7-PDT were evaluated using a mouse vagina model, a propranolol-induced cavy psoriasis model and an imiquimod (IMQ)-induced nude mouse psoriasis model. Flow cytometry was carried out to determine T lymphocyte levels. Western blotting was performed to determine protein expression, and a reverse transcription-polymerase chain reaction test was performed to determine mRNA expression., Results: The results showed that ZnPc-F7-PDT significantly inhibited the proliferation of HaCaT cells in vitro; when the light doses were fixed, changing the irradiation time or output power had little influence on the inhibition rate. ZnPc-F7-PDT significantly inhibited the hyperproliferation of mouse vaginal epithelium induced by diethylstilbestrol and improved propranolol- and IMQ-induced psoriasis-like symptoms. ZnPc-F7-PDT inhibited IMQ-induced splenomegaly and T lymphocyte abnormalities. ZnPc-F7-PDT did not appear to change T lymphocytes in the mouse vagina model. ZnPc-F7-PDT down-regulated the expression of proliferating cell nuclear antigen (PCNA), B-cell lymphoma-2 (Bcl-2), interleukin (IL)-17A mRNA and IL-17F mRNA, and up-regulated the expression of Bax., Conclusion: In conclusion, ZnPc-F7-PDT exhibited therapeutic effects in psoriasis both in vitro and in vivo and is a potential approach in the treatment of psoriasis. Potential mechanisms of these effects included the inhibition of hyperproliferation; regulation of PCNA, Bcl-2, Bax, IL-17A mRNA and IL-17F mRNA expression; and immune regulation., (© 2017 The Author(s). Published by S. Karger AG, Basel.)

Aims: Activation of hypoxia inducible factor-1 (HIF) is a hallmark in hypoxia-induced pulmonary hypertension (HPH). microRNAs play a significant role in regulating proliferation of pulmonary arterial smooth muscle cells (PASMCs) in pulmonary hypertension. Previous studies have shown that HIF-1β is a target of miR-103/107. In this present study, we aimed to investigate whether miR-103/107 regulate vascular remodeling in HPH via HIF-1β., Main Methods: The HPH model was built by hypoxia exposure in rats. Real-time PCR and Western blotting were used to determine the expression of miR-103/107 and HIF-1β. Proliferation of PASMCs was examined by 5-bromo-2'-deoxyuridine (BrdU) incorporation method. The functions of miR-103/107 on PASMCs proliferation, HIF-1α and HIF-1β expression were assessed by transfecting miR-103/107 mimics and inhibitors., Key Findings: Significant down-regulation of miR-103/107 was observed in remodeled intrapulmonary vascular in HPH rats and hypoxia-exposured PASMCs, whereas HIF-1α and HIF-1β expression were up-regulated. Hypoxia exposure induced significant proliferation of PASMCs, overexpression of miR-103/107 inhibited but miR-103/107 inhibitors exacerbated PASMCs proliferation. Gain-of-function and loss-of-function experiments showed that miR-103/107 expression was inversely correlated with HIF-1β level. No significant changes of HIF-1α expression were observed under miR-103/107 mimic treatment., Significance: Loss of suppression on HIF-1β by miR-103/107 may contribute to excess proliferation of PASMCs and vascular remodeling in hypoxic pulmonary hypertension., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Enhanced proliferation of pulmonary arterial vascular smooth muscle cells (PASMCs) is a key pathological component of vascular remodeling in hypoxia-induced pulmonary hypertension (HPH). Mammalian targeting of rapamycin (mTOR) signaling has been shown to play a role in protein translation and participate in the progression of pulmonary hypertension. Eukaryotic translation initiation factor-2α (eIF2α) is a key factor in regulation of cell growth and cell cycle, but its role in mTOR signaling and PASMCs proliferation remains unknown. Pulmonary hypertension (PH) rat model was established by hypoxia. Rapamycin was used to treat rats as an mTOR inhibitor. Proliferation of primarily cultured rat PASMCs was induced by hypoxia, rapamycin and siRNA of mTOR and eIF2α were used in loss-of-function studies. The expression and activation of eIF2α, mTOR and c-myc were analyzed. Results showed that mTOR/eIF2α signaling was significantly activated in pulmonary arteries from hypoxia exposed rats and PASMCs cultured under hypoxia condition. Treatment with mTOR inhibitor for 21 days attenuated vascular remodeling, suppressed mTOR and eIF2α activation, inhibited c-myc expression in HPH rats. In hypoxia-induced PASMCs, rapamycin and knockdown of mTOR and eIF2α by siRNA significantly abolished proliferation and increased c-myc expression. These results suggest a critical role of the mTOR/eIF2αpathway in hypoxic vascular remodeling and PASMCs proliferation of HPH. [ABSTRACT FROM AUTHOR]