Tenofovir alafenamide fumarate attenuates bleomycin-induced pulmonary fibrosis by upregulating the NS5ATP9 and TGF-β1/Smad3 signaling pathway

TDF and TAF inhibit liver cancer cell migration, invasion via p7TP3

Tenofovir disoproxil fumarate (TDF) seems to prevent hepatocellular carcinoma (HCC) in patients with chronic hepatitis B virus (HBV). However, the mechanism is still little known. This study aimed to investigate the the roles and mechanisms of TDF, tenofovir alafenamide fumarate (TAF), and entecavir (ETV) on the malignant characteristics of liver cancer cells. Using the wound-healing assays, transwell assays, matrigel transwell assays, and cell counting kit-8 (CCK-8) assays, it was possible to identify that TDF/TAF, inhibited migration, invasion, and proliferation of HepG2 cells and Huh7 cells. To investigate the mechanisms, we performed TOP/FOP-Flash system, Western blot, and RT-qPCR assays of liver cancer cells cultured with TDF/TAF and found a lower activity of Wnt/β-catenin signaling pathway compared with control cells. Finally, Hepatitis C virus p7 trans-regulated protein 3 (p7TP3), a tumor suppressor in liver cancers, was significantly increased in HepG2 cells and Huh7 cells that treated with TDF/TAF. However, entecavir (ETV)-treated liver cancer cells showed no significant difference in the malignant characteristics of liver cancer cells, activity of Wnt/β-catenin signaling pathway, and expression of p7TP3, compared with the control groups. To conclude, TDF/TAF maybe novel promising therapeutic strategy for liver cancers, including HCC and hepatoblastoma, via Wnt/β-catenin signaling pathway, by up-regulating expression of the tumor suppressor, p7TP3.

Recent Advances (2015-2020) in Drug Discovery for Attenuation of Pulmonary Fibrosis and COPD

A condition of scarring of lung tissue due to a wide range of causes (such as environmental pollution, cigarette smoking (CS), lung diseases, some medications, etc.) has been reported as pulmonary fibrosis (PF). This has become a serious problem all over the world due to the lack of efficient drugs for treatment or cure. To date, no drug has been designed that could inhibit fibrosis. However, few medications have been reported to reduce the rate of fibrosis. Meanwhile, ongoing research indicates pulmonary fibrosis can be treated in its initial stages when symptoms are mild. Here, an attempt is made to summarize the recent studies on the effects of various chemical drugs that attenuate PF and increase patients' quality of life. The review is classified based on the nature of the drug molecules, e.g., natural/biomolecule-based, synthetic-molecule-based PF inhibitors, etc. Here, the mechanisms through which the drug molecules attenuate PF are discussed. It is shown that inhibitory molecules can significantly decrease the TGF-β1, profibrotic factors, proteins responsible for inflammation, pro-fibrogenic cytokines, etc., thereby ameliorating the progress of PF. This review may be useful in designing better drugs that could reduce the fibrosis process drastically or even cure the disease to some extent.

TAF and TDF attenuate liver fibrosis through NS5ATP9, TGFβ1/Smad3, and NF-κB/NLRP3 inflammasome signaling pathways

BACKGROUND

This study aimed to investigate the roles and mechanisms of tenofovir alafenamide fumarate (TAF)/tenofovir disoproxil fumarate (TDF) in treating liver fibrosis.

METHODS

The effects of TAF/TDF on carbon tetrachloride (CCl₄)-induced liver fibrosis in C57BL/6 wild-type or nonstructural protein 5A transactivated protein 9 (NS5ATP9) knockout mice were studied. The differentiation, activation, and proliferation of LX-2 cells after TAF/TDF treatment were tested in vitro. The expression of NS5ATP9 and activities of transforming growth factor-β1 (TGFβ1)/Sekelsky mothers against decapentaplegic homolog 3 (Smad3) and NF-κB/NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome signaling pathways were detected in TAF/TDF-treated mice and LX-2 cells. The genes related to extracellular matrix accumulation were detected in vivo and in vitro after NS5ATP9 silencing or knockout.

RESULTS

TAF/TDF significantly inhibited CCl₄-induced liver fibrosis in mice, and regulated the differentiation, activation, and proliferation of hepatic stellate cells (HSCs). Furthermore, TAF/TDF suppressed the activities of TGFβ1/Smad3 and NF-κB/NLRP3 inflammasome signaling pathways in vivo and in vitro. NS5ATP9 inhibited liver fibrosis through TGFβ1/Smad3 and NF-κB signaling pathways. TAF/TDF upregulated the expression of NS5ATP9 in vivo and in vitro. Finally, TAF/TDF could only show marginal therapeutic effects when NS5ATP9 was silenced and knocked out in vivo and in vitro.

CONCLUSIONS

TAF/TDF prevented progression and promoted reversion of liver fibrosis through assembling TGFβ1/Smad3 and NF-κB/NLRP3 inflammasome signaling pathways via upregulating the expression of NS5ATP9. TAF/TDF also regulated the differentiation, activation, and proliferation of HSCs. The findings provided strong evidence for the role of TAF/TDF as a new promising therapeutic strategy in liver fibrosis.