Mirtazapine, an atypical antidepressant, mitigates lung fibrosis by suppressing NLPR3 inflammasome and fibrosis-related mediators in endotracheal bleomycin rat model.

Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible lung disease with a poor prognosis. There is currently no definitive cure for IPF. The present study establishes a platform for the development of a novel therapeutic approach for the treatment of PF using the atypical antidepressant, mirtazapine. In the endotracheal bleomycin rat model, mirtazapine interfered with the activation of NLRP3 inflammasome via downregulating the NLRP3 on the gene and protein expression levels. Accordingly, the downstream mediators IL-1ß and IL-18 were repressed. Such observation is potentially a direct result of the reported improvement in oxidative stress. Additionally, mirtazapine corrected the bleomycin-induced disparities in the levels of the fibrogenic mediators TGF-ß, PDGF-BB, and TIMP-1, in consequence, the lung content of hydroxyproline and the expression of α-SMA were reduced. Besides, mirtazapine curbed the ICAM-1 and the chemotactic cytokines MCP-1 and CXCL4. This protective property of mirtazapine resulted in improving the BALF total and differential cell counts, diminishing LDH activity, and reducing the BALF total protein. Moreover, the inflammation and fibrosis scores were accordingly lower. To conclude, we reveal for the first time the efficacy of mirtazapine as a potential treatment for PF. The combination of social isolation, sleep problems, breathing difficulties, and fear of death can lead to psychological distress and depression in patients with IPF. Hence, mirtazapine is a promising treatment option that may improve the prognosis for IPF patients due to its antifibrotic effects, as well as its ability to alleviate depressive episodes.

Innovative challenge for the inhibition of hepatocellular carcinoma progression by combined targeting of HSP90 and STAT3/HIF-1α signaling.

Hepatocellular carcinoma (HCC) is the third foremost cause of cancer-related deaths. HCC has a very bad prognosis because it is asymptomatic in the early stages, resulting in a late diagnosis, and it is highly resistant to conventional chemotherapy. Such chemotherapies have been proven disappointing because they provide extremely low survival benefits. This study discloses that the STAT3/HIF-1α is an auspicious therapeutic attack site for conceivable repression of HCC development. A site that can be targeted by simultaneous administration of a STAT3 inhibitor in the context of HSP90 inhibition. 17-DMAG binds to HSP90 and constrains its function, resulting in the degradation of HSP90 client proteins HIF-1α and STAT3. Hypoxia recruits STAT3/HIF-1α complex within the VEGF promoter. Additionally, it was acknowledged that STAT3 is an essential mediator of VEGF transcription by direct binding to its promoter. Furthermore, it induces HIF-1α stability and enhances its transcriptional activity. Herein, we revealed that the combination therapy using 17-DMAG and nifuroxazide, a STAT3 inhibitor, repressed the diethylnitrosamine-induced alterations in the structure of the liver. This effect was mediated via decreasing the levels of the HSP90 client proteins HIF-1α and pSTAT3 resulting in the suppression of the STAT3/HIF-1α complex transcriptional activity. To conclude, 17-DMAG/NFXZD combination therapy-induced disruption in the STAT3/HIF-1α loop led to a potential antiangiogenic activity and showed apoptotic potential by inhibiting autophagy and inducing ROS/apoptosis signaling. Additionally, this combination therapy exhibited promising survival prolongation in mice with HCC. Consequently, the use of 17-DMAG/NFXZD renders an inspirational perspective in managing HCC. However, further investigations are compulsory.

Pimitespib, an HSP90 inhibitor, augments nifuroxazide-induced disruption in the IL-6/STAT3/HIF-1α autocrine loop in rats with bleomycin-challenged lungs: Evolutionary perspective in managing pulmonary fibrosis.

Idiopathic pulmonary fibrosis is a fatal lung disorder in which the etiology and pathogenesis are still unobvious. Effective treatments are urgently needed considering that lung transplantation is the only treatment that could improve outcomes. This study aimed to investigate the therapeutic significance of the dual administration of pimitespib, an HSP90 inhibitor, and nifuroxazide, a STAT3 inhibitor, against bleomycin-induced pulmonary fibrosis in rats. Our results revealed that pimitespib/nifuroxazide inhibited bleomycin-induced alterations in the structure and the function of the lungs. They demonstrated significant decreases in the BALF total and differential cell counts, LDH activity, and total protein. Concurrently, there was a reduction in the accumulation of collagen as proved by decreased hydroxyproline and the gene expression of COL1A1 accompanied by lower levels of PDGF-BB, TIMP-1, and TGF-ß. The levels of IL-6 were also downregulated. Pimitespib-induced inhibition of HSP90 led to subsequent inhibition of HIF-1α and STAT3 client proteins since the closed HSP90 would not enclose its client proteins. Therefore, pimitespib resulted in the repression of HIF-1α/CREB-p300 HAT as well as the STAT3/CREB-p300 HAT nuclear interactions. On the other hand, nifuroxazide resulted in a notable decline in pSTAT3 and HIF-1α levels. Subsequently, the combined effects of both drugs led to a substantial reduction in ECM deposition. Herein, pimitespib augmented nifuroxazide-induced disruption in the IL-6/STAT3/HIF-1α autocrine loop. Our findings also disclose that this novel loop is a promising therapeutic attack site for possible pulmonary fibrosis repression studies. Therefore, the use of pimitespib/nifuroxazide embodies an evolutionary perspective in managing pulmonary fibrosis.