Thal protects against paraquat-induced lung injury through a microRNA-141/HDAC6/IκBα-NF-κB axis in rat and cell models

Anti-inflammatory effect of thalidomide in an experimental lung donor model of brain death

Lung transplantation stands as a vital treatment for severe lung diseases, primarily sourcing organs from donors with brain death (BD). This research delved into the potential anti-inflammatory effects of thalidomide in rats with BD-induced lung complications. In this study twenty-four Wistar rats were divided into three groups: the control (CTR), brain death (BD) and brain death + thalidomide (TLD) groups. Post specific procedures, a 360 min monitoring period ensued. Comprehensive analyses of blood and heart-lung samples were conducted. Elevated IL-6 levels characterized both BD and TLD groups relative to the CTR (p = 0.0067 and p = 0.0137). Furthermore, TNF-α levels were notably higher in the BD group than both CTR and TLD (p = 0.0152 and p = 0.0495). Additionally, IL-1β concentrations were significantly pronounced in both BD and TLD compared to CTR, with the BD group surpassing TLD (p = 0.0256). Immunohistochemical assessments revealed augmented NF-ĸB expression in the BD group in comparison to both CTR and TLD (p = 0.0006 and p = 0.0005). With this study we can conclude that BD induced acute pulmonary inflammation, whereas thalidomide manifested a notable capability in diminishing key inflammatory markers, indicating its prospective therapeutic significance in lung transplantation scenarios.

Thalidomide interaction with inflammation in idiopathic pulmonary fibrosis

The "Thalidomide tragedy" is a landmark in the history of the pharmaceutical industry. Despite limited clinical trials, there is a continuous effort to investigate thalidomide as a drug for cancer and inflammatory diseases such as rheumatoid arthritis, lepromatous leprosy, and COVID-19. This review focuses on the possibilities of targeting inflammation by repurposing thalidomide for the treatment of idiopathic pulmonary fibrosis (IPF). Articles were searched from the Scopus database, sorted, and selected articles were reviewed. The content includes the proven mechanisms of action of thalidomide relevant to IPF. Inflammation, oxidative stress, and epigenetic mechanisms are major pathogenic factors in IPF. Transforming growth factor-β (TGF-β) is the major biomarker of IPF. Thalidomide is an effective anti-inflammatory drug in inhibiting TGF-β, interleukins (IL-6 and IL-1β), and tumour necrosis factor-α (TNF-α). Thalidomide binds cereblon, a process that is involved in the proposed mechanism in specific cancers such as breast cancer, colon cancer, multiple myeloma, and lung cancer. Cereblon is involved in activating AMP-activated protein kinase (AMPK)-TGF-β/Smad signalling, thereby attenuating fibrosis. The past few years have witnessed an improvement in the identification of biomarkers and diagnostic technologies in respiratory diseases, partly because of the COVID-19 pandemic. Hence, investment in clinical trials with a systematic plan can help repurpose thalidomide for pulmonary fibrosis.

E2F1 regulates miR-215-5p to aggravate paraquat-induced pulmonary fibrosis via repressing BMPR2 expression

Background

Pulmonary fibrosis is considered to be an irreversible lung injury, which can be caused by paraquat (PQ) poisoning. MiRNAs have been demonstrated crucial roles in pulmonary fibrosis caused by numerous approaches including PQ induction. The purpose of this study was to investigate the role and the underlying mechanism of miR-215 in PQ-induced pulmonary fibrosis.

Methods

The cell and animal models of pulmonary fibrosis were established through PQ intervention. Cell viability was performed to test by MTT assay. Immunofluorescence assay was used to detect COL1A1 expression and its location. The relationships among E2F1, miR-215-5p, and BMPR2 were validated by dual luciferase reporter gene assay, chromatin immunoprecipitation and RNA-binding protein immunoprecipitation. Lung morphology was evaluated by hematoxylin and eosin staining.

Results

MiR-215-5p was upregulated in PQ-induced pulmonary fibrosis in vitro and in vivo. MiR-215-5p silencing relieved PQ-induced pulmonary fibrosis progression by enhancing cell viability and reducing the expression of fibrosis-related markers (COL1A1, COL3A1, and α-SMA). Mechanistically, miR-215-5p directly targeted BMRP2. BMPR2 knockdown abolished the suppressive effects of miR-215-5p knockdown on PQ-induced pulmonary fibrosis. In addition, E2F1 interacted with miR-215-5p promoter and positively regulated miR-215-5p expression. E2F1 downregulation reduced miR-215-5p level and promoted BMPR2 level via regulating TGF-β/Smad3 pathway, and then suppressed PQ-induced pulmonary fibrosis, whereas these effects were compromised by miR-215-5p sufficiency.

Conclusion

MiR-215-5p was activated by E2F1 to repress BMPR2 expression and activate TGF-β/Smad3 pathway, which aggravated PQ-induced pulmonary fibrosis progression. Targeting the E2F1/miR-215-5p/BMPR2 axis might be a new approach to alleviate PQ-induced pulmonary fibrosis.

XueFu ZhuYu Decoction Alleviates Cardiopulmonary Bypass-Induced NLRP3 Inflammasome-Dependent Pyroptosis by Inhibiting IkB-α/NF-κB Pathway in Acute Lung Injury Rats

XueFu ZhuYu Decoction (XFZYD) is an effective prescription that is widely used to improve blood circulation by removing blood stasis. This study aimed to investigate the effects and the underlying molecular mechanisms of XFZYD on lung pyroptosis in cardiopulmonary bypass- (CPB-) induced acute lung injury (ALI) rats. A rat model of ALI was induced by CPB treatment after XFZYD, Ac-YVAD-CMK, and Bay-11-7082 administration. The respiratory index (RI) and oxygenation index (OI) were determined at each time point. The levels of interleukin (IL)-1β, IL-6, IL-18, and TNF-α in serum and lung were measured by enzyme-linked immunosorbent assays (ELISA). Moreover, the protein levels, neutrophil counts, and total cell of bronchoalveolar lavage fluid (BALF) were detected. Additionally, Myeloperoxidase (MPO) expression was detected by immunohistochemical assay. Lung injury was evaluated with the wet/dry (W/D) ratio and pathologic changes, respectively. Besides, the expression of NLRP3 inflammasome and IkB-α/NF-κB pathway proteins was estimated by immunofluorescence, quantitative real-time PCR (qRT-PCR), and Western blotting assays, respectively. XFZYD pretreatment significantly ameliorated pulmonary ventilation function and reduced the CPB-induced lung histopathological injury, inflammatory cell infiltration in BALF and lung, and the apoptosis of lung cells. Interestingly, XFZYD decreased the CPB-induced NLRP3, ASC, Caspase-1 p20, Pro-GSDMD, GSDMD p30, IL-18, IL-1β p-P65, and p-IKBα mRNA or protein levels in lung tissues in ALI model rats. In summary, these findings suggest that XFZYD effectively mitigates NLRP3 inflammasome-dependent pyroptosis in CPB-induced ALI model rats, possibly by inhibiting the IkB-α/NF-κB pathway in the lung.

Targeting HDAC6 to Overcome Autophagy-Promoted Anti-Cancer Drug Resistance

Histone deacetylases (HDACs) regulate gene expression through the epigenetic modification of chromatin structure. HDAC6, unlike many other HDACs, is present in the cytoplasm. Its deacetylates non-histone proteins and plays diverse roles in cancer cell initiation, proliferation, autophagy, and anti-cancer drug resistance. The development of HDAC6-specific inhibitors has been relatively successful. Mechanisms of HDAC6-promoted anti-cancer drug resistance, cancer cell proliferation, and autophagy are discussed. The relationship between autophagy and anti-cancer drug resistance is discussed. The effects of combination therapy, which includes HDAC6 inhibitors, on the sensitivity of cancer cells to chemotherapeutics and immune checkpoint blockade are presented. A summary of clinical trials involving HDAC6-specific inhibitors is also presented. This review presents HDAC6 as a valuable target for developing anti-cancer drugs.

Thalidomide Alleviates Pulmonary Fibrosis Induced by Silica in Mice by Inhibiting ER Stress and the TLR4-NF-κB Pathway

Silicosis is the most prevalent occupational disease in China. It is a form of pulmonary fibrosis caused by the inhalation of silicon particles. As there is no cure for the potentially lethal and progressive condition, the treatment of silicotic fibrosis is an important and difficult problem to address. Thalidomide, a drug with anti-inflammatory and immunoregulatory properties, has been reported to have lung-protective effects. The purpose of this study was to observe the therapeutic effect of thalidomide on silicotic mice and to determine the protective mechanism. By using silicotic mice models and MH-S cells, we found the expression of endoplasmic reticulum stress (ER stress) and Toll-like receptor 4 (TLR4)-nuclear factor kappa-B (NF-κB) pathway as well as inflammation-related factors were upregulated in the macrophages of silicotic mice. The same indexes were detected in silica-stimulated MH-S cells, and the results were consistent with those in vivo. That is, silica activated ER stress and the TLR4-NF-κB pathway as well as the inflammatory response in vitro. Treating both silicotic mice and silica-stimulated MH-S cells with thalidomide inhibited ER stress and the TLR4-NF-κB pathway as well as the inflammatory response. The present study demonstrates thalidomide as a potential therapeutic agent against silicosis.

MicroRNA-210-5p alleviates cardiac fibrosis via targeting transforming growth factor-beta type I receptor in rats on high sodium chloride (NaCl)-based diet

The present study was designed to explore whether high sodium chloride (NaCl)-based diet (HSD) caused cardiac fibrosis regardless of blood pressure in Sprague-Dawley (SD) rats, and to further determine the effects and the underlying mechanisms of microRNA (miR)-210-5p on HSD-induced cardiac fibrosis in rats or NaCl-induced cardiac fibroblast activation in neonatal rat cardiac fibroblasts (NRCFs). The SD rats received 8% HSD, and NRCFs were treated with NaCl. The levels of collagen I, alpha-smooth muscle actin (α-SMA) and transforming growth factor-beta 1 (TGF-β1) were increased in the heart of hypertension (HTN), hypertension-prone (HP) and hypertension-resistant (HR) rats on HSD in vivo. NaCl increased the levels of collagen I, α-SMA and TGF-β1 in NRCFs in vitro. The level of miR-210-5p was reduced in both NBD-induced rats' hearts and NaCl-treated NRCFs, which was consistent with the results of miR high-throughput sequencing in NRCFs. The HSD or NaCl-induced increases of collagen I, α-SMA and TGF-β1 were inhibited by miR-210-5p agomiR in vitro and in vivo, respectively. miR-210-5p antagomiR could mimic the pathological effects of NaCl in NRCFS. Bioinformatics analysis and luciferase reporter assays demonstrated that TGF-β type I receptor (TGFBR1) was a direct target gene of miR-210-5p. These results indicated that HSD resulted in cardiac fibrosis regardless of blood pressure. The upregulation of miR-210-5p could attenuate cardiac fibroblast activation in NRCFS via targeting TGFBR1. Thus, upregulating miR-210-5p might be a strategy for the treatment of cardiac fibrosis.

Thal protects against paraquat-induced lung injury through a microRNA-141/HDAC6/IκBα-NF-κB axis in rat and cell models

The protective functions of thalidomide in paraquat (PQ)-induced injury have been reported. But the mechanisms remain largely unknown. In this research, a PQ-treated rat model was established and further treated with thalidomide. Oedema and pathological changes, oxidative stress, inflammation, fibrosis and cell apoptosis in rat lungs were detected. A PQ-treated RLE-6TN cell model was constructed, and the viability and apoptosis rate of cells were measured. Differentially expressed microRNAs (miRNAs) after thalidomide administration were screened out. Binding relationship between miR-141 and histone deacetylase 6 (HDAC6) was validated. Altered expression of miR-141 and HDAC6 was introduced to identify their involvements in thalidomide-mediated events. Consequently, thalidomide administration alone exerted no damage to rat lungs; in addition it reduced PQ-induced oedema. The oxidative stress, inflammation and cell apoptosis in rat lungs were reduced by thalidomide. In RLE-6TN cells, thalidomide increased cell viability and decreased apoptosis. miR-141 was responsible for thalidomide-mediated protective events by targeting HDAC6. Overexpression of HDAC6 blocked the protection of thalidomide against PQ-induced injury via activating the IkBα-NF-κB signalling pathway. Collectively, this study evidenced that thalidomide protects lung tissues from PQ-induced injury through a miR-141/HDAC6/IkBα-NF-κB axis.