Naringenin inhibits autophagy and epithelial-mesenchymal transition of human lens epithelial cells by regulating the Smad2/3 pathway

Targeting PYK2, entrectinib allays anterior subcapsular cataracts in mice by regulating TGFβ2 signaling pathway

BACKGROUND

Fibrosis cataract occurs in patients receiving cataract extraction. Still, no medication that can cure the disease exists in clinical. This study aims to investigate the effects and mechanisms of Entrectinib on fibrotic cataract in vitro and in vivo.

METHODS

The human lens cells line SRA 01/04 and C57BL/6J mice were applied in the study. Entrectinib was used in animals and cells. Cataract severity was assessed by slit lamp and Hematoxylin and Eosin staining. Expression of alpha-smooth muscle actin, fibronectin, and collagen I were examined by real-time quantitative PCR, western blotting, and immunofluorescence. Cell proliferation was evaluated by Cell Counting Kit-8. Cell migration was measured by wound healing and transwell assays. Molecular docking, Drug Affinity Responsive Target Stability, and Cellular Thermal Shift Assay were applied to seek and certify the target of Entrectinib treating fibrosis cataract.

RESULTS

Entrectinib can ameliorate fibrotic cataract in vitro and in vivo. At the RNA and the protein levels, the expression of alpha-smooth muscle actin, collagen I, and fibronectin can be downgraded by Entrectinib, while E-cadherin can be upregulated. The migration and proliferation of cells were inhibited by Entrectinib. Mechanistically, Entrectinib obstructs TGFβ2/Smad and TGFβ2/non-Smad signaling pathways to hinder the fibrosis cataract by targeting PYK2 protein.

CONCLUSIONS

Targeting with PYK2, Entrectinib can block TGF-β2/Smad and TGF-β2/non-Smad signaling pathways, lessen the activation of EMT, and alleviate fibrosis cataract. Entrectinib may be a potential treatment for fibrosis cataract in clinic.

Herb pair of Rhubarb-Astragalus mitigates renal interstitial fibrosis through downregulation of autophagy via p38-MAPK/TGF-β1 and p38-MAPK/smad2/3 pathways

BACKGROUND

Chronic kidney disease (CKD) has a high incidence and poor prognosis; however, no effective treatment is currently available. Our previous study found that the improvement effect of the herb pair of Rhubarb-Astragalus on CKD is likely related to the inhibition of the TGF-β1/p38-MAPK pathway. In the present study, a p38-MAPK inhibitor was used to further investigate the inhibitory effect of Rhubarb-Astragalus on the TGF-β1/p38-MAPK pathway and its relationship with autophagy.

METHODS

A rat model of unilateral ureteral obstruction (UUO) was established, and a subgroup of rats was administered Rhubarb-Astragalus. Renal function and renal interstitial fibrosis (RIF) were assessed 21 d after UUO induction. In vitro, HK-2 cells were treated with TGF-β1 and a subset of cells were treated with Rhubarb-Astragalus or p38-MAPK inhibitor. Western blotting, immunohistochemistry, and qRT-PCR analyses were used to detect the relevant protein and mRNA levels. Transmission electron microscopy was used to observe autophagosomes.

RESULTS

Rhubarb-Astragalus treatment markedly decreased the elevated levels of blood urea nitrogen, serum creatinine, and urinary N-acetyl-β-D-glucosaminidase; attenuated renal damage and RIF induced by UUO; and reduced the number of autophagosomes and lysosomes in UUO-induced renal tissues. Additionally, Rhubarb-Astragalus reduced the protein and mRNA levels of α-SMA, collagen I, LC3, Atg3, TGF-β1, p38-MAPK, smad2/3, and TAK1 in renal tissues of UUO rats. Rhubarb-Astragalus also reduced protein and mRNA levels of these indicators in vitro. Importantly, the effect of the p38-MAPK inhibitor was similar to that of Rhubarb-Astragalus.

CONCLUSIONS

Rhubarb-Astragalus improves CKD possibly by downregulating autophagy via the p38-MAPK/TGF-β1 and p38-MAPK/smad2/3 pathways.

The protective roles of citrus flavonoids, naringenin, and naringin on endothelial cell dysfunction in diseases

The endothelial cells (ECs) make up the inner lining of blood vessels, acting as a barrier separating the blood and the tissues in several organs. ECs maintain endothelium integrity by controlling the constriction and relaxation of the vasculature, blood fluidity, adhesion, and migration. These actions of ECs are efficiently coordinated via an intricate signaling network connecting receptors, and a wide range of cellular macromolecules. ECs are naturally quiescent i.e.; they are not stimulated and do not proliferate. Upon infection or disease, ECs become activated, and this alteration is pivotal in the pathogenesis of a spectrum of human neurological, cardiovascular, diabetic, cancerous, and viral diseases. Considering the central position that ECs play in disease pathogenesis, therapeutic options have been targeted at improving ECs integrity, assembly, functioning, and health. The dietary intake of flavonoids present in citrus fruits has been associated with a reduced risk of endothelium dysfunction. Naringenin (NGN) and Naringin (NAR), major flavonoids in grapefruit, tomatoes, and oranges possess anti-inflammatory, antioxidant properties, and cell survival potentials, which improve the health of the vascular endothelium. In this review, we provide a comprehensive summary and present the advances in understanding of the mechanisms through which NGN and NAR modulate the biomarkers of vascular dysfunction and protect the endothelium against unresolved inflammation, oxidative stress, atherosclerosis, and angiogenesis. We also provide perspectives and suggest further studies that will help assess the efficacy of citrus flavonoids in the therapeutics of human vascular diseases.

Larotrectinib induces autophagic cell death through AMPK/mTOR signalling in colon cancer

Larotrectinib (Lar) is a highly selective and potent small-molecule inhibitor used in patients with tropomyosin receptor kinase (TRK) fusion-positive cancers, including colon cancer. However, the underlying molecular mechanisms specifically in patients with colon cancer have not yet been explored. Our data showed that Lar significantly suppressed proliferation and migration of colon cancer cells. In addition, Lar suppressed the epithelial-mesenchymal transition (EMT) process, as evidenced by elevation in E-cadherin (E-cad), and downregulation of vimentin and matrix metalloproteinase (MMP) 2/9 expression. Furthermore, Lar was found to activate autophagic flux, in which Lar increased the ratio between LC3II/LC3I and decreased the expression of p62 in colon cancer cells. More importantly, Lar also increased AMPK phosphorylation and suppressed mTOR phosphorylation in colon cancer cells. However, when we silenced AMPK in colon cancer cells, Lar-induced accumulation of autolysomes as well as Lar-induced suppression of the EMT process were significantly diminished. An in vivo assay also confirmed that tumour volume and weight decreased in Lar-treated mice than in control mice. Taken together, this study suggests that Lar significantly suppresses colon cancer proliferation and migration by activating AMPK/mTOR-mediated autophagic cell death.

Network Pharmacology and Experimental Verification Strategies to Illustrate the Mechanism of Jian-Pi-Yi-Shen Formula in Suppressing Epithelial-Mesenchymal Transition

Jian-Pi-Yi-Shen formula (JPYSF), a traditional Chinese medicine, has been recommended to treat renal fibrosis for decades. Previous studies had shown that JPYSF could inhibit epithelial–mesenchymal transition (EMT), an important regulatory role in renal fibrosis. However, the mechanism of JPYSF action is largely unknown. In this study, network pharmacology and experimental verification were combined to elucidate and identify the potential mechanism of JPYSF against renal fibrosis by suppressing EMT at molecular and pathway levels. Network pharmacology was first performed to explore the mechanism of JPYSF against renal fibrosis targeting EMT, and then a 5/6 nephrectomy (5/6 Nx)-induced rat model of renal fibrosis was selected to verify the predictive results by Masson’s trichrome stains and western blot analysis. Two hundred and thirty-two compounds in JPYSF were selected for the network approach analysis, which identified 137 candidate targets of JPYSF and 4,796 known therapeutic targets of EMT. The results of the Gene Ontology (GO) function enrichment analysis included 2098, 88, and 133 GO terms for biological processes (BPs), molecular functions (MFs), and cell component entries, respectively. The top 10 enrichment items of BP annotations included a response to a steroid hormone, a metal ion, oxygen levels, and so on. Cellular composition (CC) is mainly enriched in membrane raft, membrane microdomain, membrane region, etc. The MF of JPYSF analysis on EMT was predominately involved in proximal promoter sequence-specific DNA binding, protein heterodimerization activity, RNA polymerase II proximal promoter sequence-specific DNA binding, and so on. The involvement signaling pathway of JPYSF in the treatment of renal fibrosis targeting EMT was associated with anti-fibrosis, anti-inflammation, podocyte protection, and metabolism regulation. Furthermore, the in vivo experiments confirmed that JPYSF effectively ameliorated interstitial fibrosis and inhibited the overexpression of α-SMA, Wnt3a, and β-catenin, and increased the expression of E-cadherin by wnt3a/β-catenin signaling pathway in 5/6 Nx-induced renal fibrosis rats. Using an integrative network pharmacology-based approach and experimental verification, the study showed that JPYSF had therapeutic effects on EMT by regulating multi-pathway, among which one proven pathway was the Wnt3a/β-catenin signaling pathway. These findings provide insights into the renoprotective effects of JPYSF against EMT, which could suggest directions for further research of JPYSF in attenuating renal fibrosis by suppressing EMT.

Naringenin Regulates FKBP4/NR3C1/NRF2 Axis in Autophagy and Proliferation of Breast Cancer and Differentiation and Maturation of Dendritic Cell

NRF2 is an important regulatory transcription factor involved in tumor immunity and tumorigenesis. In this study, we firstly identified that FKBP4/NR3C1 axis was a novel negative regulator of NRF2 in human breast cancer (BC) cells. The effect of FKBP4 appeared to be at protein level of NRF2 since it could not suppress the expression of NRF2 at mRNA level. Bioinformatics analysis and in vitro experiments further demonstrated that FKBP4 regulated NRF2 via regulating nuclear translocation of NR3C1. We then reported that naringenin, a flavonoid, widely distributed in citrus and tomato, could suppress autophagy and proliferation of BC cells through FKBP4/NR3C1/NRF2 signaling pathway in vitro and in vivo. Naringenin was also found to promote dendritic cell (DC) differentiation and maturation through FKBP4/NR3C1/NRF2 axis. Therefore, our study found that naringenin could induce inhibition of autophagy and cell proliferation in BC cells and enhance DC differentiation and maturation, at least in part, though regulation of FKBP4/NR3C1/NRF2 signaling pathway. Identification of FKBP4/NR3C1/NRF2 axis would provide insights for novel anti-tumor strategy against BC among tumor microenvironment.