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Objective To investigate the effects of niclosamide on S100A4 expression and pathological angiogenesis of hepatopulmonary syndrome (HPS) in rats. Methods Thirty male SD rats were randomly divided into control group (Sham group, n=6), common bile duct ligation (CBDL) group (n=18) and niclosamide treatment group (NIC group, n=6). The rats of the NIC group were gavaged with niclosamide suspension for 1 week since the first day of the third week after modelling, and the rats were dissected at the end of the fifth week to assess the pathological changes and disease progression of liver and lung tissues by HE and Masson staining. Immunofluorescence assay was used to detect the location and intensity of S100A4 and CD31 expression in the lung of rats. The expression of S100A4 at mRNA and protein levels was detected using qPCR and Western blotting. Pulmonary microvascular endothelial cells (PMVECs) were treated with small interfering RNA (siRNA) serum of HPS rats and nichosamide, respectively, and their effects on cell migration and tube-forming abilities were observed. Results Both mRNA and protein expression of S100A4 in lung tissue of the CBDL group rats were increased with disease progression, and the expression levels were higher than those in the Sham group (P < 0.000 1); The lung mRNA and protein levels of S100A4 were lower in the NIC group than the CBDL group at the 5th week, but still higher than those in the Sham group. After knockdown of S100A4 using siRNA in PMVECs, the migration and tube-forming abilities were reduced when compared with the NC group (P < 0.000 1). HE staining displayed that pulmonary pathological changes were milder in the NIC group than the CBDL group at the 5th week, while no such effect was found in the liver tissues. Masson staining showed that hepatic fibrosis was not obviously ameliorated in the NIC group. The migration and tube-forming abilities of the cells was significantly increased in the CBDL group after the 5 weeks of serum stimulation compared to the Sham rats, while niclosamide treatment reversed this phenomenon (P < 0.000 1). Conclusion S100A4 can accelerate the progression of HPS by promoting pulmonary micro-angiogenesis in HPS rats, and niclosamide inhibits the expression of S100A4 in the lung and thus delays the progression of HPS.

Tubular injury and oxidative stress are involved in the pathogenesis of diabetic kidney disease (DKD). Astragaloside IV (ASIV) is a natural antioxidant. The effects and underlying molecular mechanisms of ASIV on DKD have not been elucidated. The db/db mice and high-glucose-stimulated HK2 cells were used to evaluate the beneficial effects of ASIV in vivo and in vitro. Succinylated proteomics was used to identify novel mechanisms of ASIV against DKD and experimentally further validated. ASIV alleviated renal dysfunction and proteinuria, downregulated fasting blood glucose, and upregulated insulin sensitivity in db/db mice. Meanwhile, ASIV alleviated tubular injury, oxidative stress, and mitochondrial dysfunction in vivo and in vitro. Mechanistically, ASIV reversed downregulated 17beta-hydroxysteroid dehydrogenase type 10 (HSD17B10) lysine succinylation by restoring carnitine palmitoyl-transferase1alpha (Cpt1a or CPT1A) activity in vivo and in vitro. Molecular docking and cell thermal shift assay revealed that ASIV may bind to CPT1A. Molecular dynamics simulations demonstrated K99 succinylation of HSD17B10 maintained mitochondrial RNA ribonuclease P (RNase P) stability. The K99R mutation of HSD17B10 induced oxidative stress and disrupted its binding to CPT1A or mitochondrial ribonuclease P protein 1 (MRPP1). Importantly, ASIV restored the interaction between HSD17B10 and MRPP1 in vivo and in vitro. We also demonstrated that ASIV reversed high-glucose-induced impaired RNase P activity in HK2 cells, which was suppressed upon K99R mutation of HSD17B10. These findings suggest that ASIV ameliorates oxidative stress-associated proximal tubular injury by upregulating CPT1A-mediated K99 succinylation of HSD17B10 to maintain RNase P activity., (© 2024 John Wiley & Sons Ltd.)

Objectives: Hepatopulmonary syndrome is a serious respiratory injury caused by chronic liver disease. Excessive pulmonary capillary angiogenesis is the key pathological event. However, the mechanism of microRNA regulatory pulmonary capillary angiogenesis is still unclear., Materials and Methods: The hepatopulmonary syndrome rat model was constructed by Common bile duct ligation (CBDL) surgery. The expression tread of miR181-5p and Wif1 was detected by qRT-PCR and western blot in various tissues and disease processes. Wif1 was predicted as one of the potential target genes of miR181-5p by bioinformatic assay. miR181-5p mimics and inhibitors were used to increase/decrease miR181-5p levels in pulmonary microvascular cells. And Wif-1 specific recombinant lentiviruses were used to up-regulate and down-regulate Wif1 in pulmonary microvascular cells. Then, CCK8, Transwell, and tube formation assay were used for pulmonary microvascular cell proliferation, migration, and tube formation. And Dual-luciferase reporter assay was used to assess that miR181-5p may direct regulate Wif-1 in HPS rats., Results: The result showed miR181-5p specifically activates the Wnt signaling pathway by inhibiting Wif1 and then promotes pulmonary microvascular cell proliferation, migration, and tube formation, thereby accelerating the process of HPS. We finally verified Wif1 as a novel and direct target of miR181-5p in HPS., Conclusion: Taken together, we revealed an important miR-181-5p/Wif1/Wnt pathway in regulating pathological angiogenesis. It will prove beneficial as a therapeutic strategy for hepatopulmonary syndrome., Competing Interests: The authors declare no conflict of interest.