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Background: The resistance mechanism of the third generation of epidermal growth factor (EGFR) tyrosine kinase inhibitor (TKI) osimertinib is complex. Epithelial mesenchymal transition (EMT) is a common mechanism of EGFR‐TKI acquired resistance. Snail is an important transcription factor related to EMT. Whether targeting Snail can reverse the resistance of osimertinib by downregulating Snail is unknown. Methods: The presence of EMT in H1975/OR (osimertinib resistance) cells was confirmed by transwell assay. To explore the EMT role in resistance, the expression levels of EMT markers were detected in both parental cells H1975 and resistant cells H1975OR. We used RNA interference technology to knockdown the key regulator Snail in resistant cells. After the interference efficiency was confirmed, changes in EMT‐related molecules of Snail were explicitly downregulated, and changes in sensitivity and migration and invasion ability were also examined. We used CDK4/6 inhibitor to test the ability of reversing drug resistance by downregulating Snail. Results: Compared with the H1975 cell line, the H1975/OR resistant cell line showed increased invasiveness, upregulated expression of vimentin and downregulation of E‐cadherin. EMT occurred in the H1975/OR resistant cell line. The expression of Snail was upregulated in the osimertinib‐resistant cell line H1975/OR. Knockdown of Snail increased the sensitivity of H1975/OR cells to osimertinib. CDK4/6 inhibitor palbociclib could downregulate the expression of Snail. CDK 4/6 inhibitor palbociclib combined with osimertinib could reverse the resistance of osimertinib in H1975/OR. Conclusions: Snail plays an important role in the third generation of EGFR‐TKI osimertinib resistance, which may be reversed by downregulating Snail. [ABSTRACT FROM AUTHOR]

Background: Yulangsan flavone (YLSF) was extracted from the root of Millettia pulchra Kurz var-laxior (Dunn) Z. Wei, which has been widely used for liver disease treatment in the Guangxi province of China.Hypothesis/purpose: The study was conducted to demonstrate the hepatoprotective effects of YLSF against CCl4-induced hepatic fibrosis in rats, meanwhile revealing the potential mechanism.Study Design: Sprague-Dawley (SD) rats of both sexes were randomly divided into two groups: hepatic fibrosis group and normal control (NC) group. The rats in the hepatic fibrosis group were given 1 ml/kg 50% CCl4 (1:1 mixed with peanut oil), while those in the NC group were given 1 ml/kg normal saline (NS), both via intragastric administration. The established experimental rat model from the hepatic fibrosis group was confirmed by pathological inspection and randomly divided into five groups: three YLSF groups (20 mg/kg, 40 mg/kg and 80 mg/kg), a colchicine group (0.20 mg/kg) and a model group (10 ml/kg NS). All rats were treated with corresponding drugs or NS once a day for four consecutive weeks. Twenty-four hours after the last administration, blood serum and hepatic tissue were collected.Methods: The activities of ALT and AST in the serum and the levels of SOD, MDA, GSH and GSH-Px in hepatic tissue were analysed, the indexes of liver, spleen and thymus were counted, the degree of hepatic injury was examined using HE and Masson staining, and the mRNA expression of Col-1, TIMP-1 and TGF-β1 in hepatic tissues was detected.Results: Compared with the model group, experimental results showed that YLSF and colchicine could reduce the levels of AST, ALT and MDA, increase the levels of SOD, GSH and GSH-Px, enhance rat survivability, decrease the liver, spleen and thymus index, significantly lessen collagen deposition and tissue damage and down-regulate the mRNA expression of Col-1, TIMP-1 and TGF-β1.Conclusions: Our findings confirm that YLSF has a certain curative effect on rats with liver fibrosis induced by CCl4, and its mechanism may include attenuating free radicals, inhibiting lipid peroxidation and accelerating extracellular matrix degradation by down-regulating expression of related genes. [ABSTRACT FROM AUTHOR]

Background: Averrhoacarambola L., which is a folk medicine used in diabetes mellitus (DM) in ancient China, has been reported to have anti-diabetic efficacy. Aims: The aim of this study was to evaluate the hypoglycemic effect of the extract of Averrhoacarambola L. root (EACR) on the regulation of the Toll-like receptor 4 (TLR4)-Nuclear-factor kappa B (NF-κB) pathway in streptozotocin (STZ)-induced diabetic mice. Methods: the mice were injected with STZ (120 mg/kg body weight) via a tail vein. After 72 h, the mice with FBG > 11.1 mmol/L were confirmed as having diabetes. Subsequently, the mice were treated intragastrically with EACR (300, 600, 1200 mg/kg body weight/d) and metformin (320 mg/kg body weight/d) for 14 days. Results: As a result the serum fasting blood glucose (FBG), interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-a) levels were decreased following EACR administration. Immunohistochemical analysis revealed that the pancreatic tissue expression levels of TLR4 and NF-κB were downregulated after EACR administration. EACR suppressed pancreatic mRNA expression level of TLR4 and blocked the downstream NF-κB pathway in the pancreas. According to Western blot analysis EACR suppressed pancreatic TLR4 and NF-κB protein expression levels. Histopathological examination of the pancreas showed that STZ-induced pancreas lesions were alleviated by the EACR treatment. Conclusion: These findings suggest that the modulation of the IL-6 and TNF-a inflammatory cytokines and the suppression of the TLR4-NF-κB pathway are most likely involved in the anti-hyperglycemic effect of EACR in STZ-induced diabetic mice. [ABSTRACT FROM AUTHOR]

Aim: The primary objective of this study was to study the effects of 17-methoxyl-7-hydroxybenzene- furanchalcone (MHBFC) on pressure overload-induced cardiac remodeling in rats, as well as the endothelial mechanisms based on PGI2 Methods: Six weeks following surgery, rats were divided randomly into the following groups: a sham group, a model group, an MHBFC 12 mg/kg/day group (MHBFC 12), an indomethacin 2 mg/kg/day group (Indo 2), and an Indo 2+ MHBFC 12 group. The MS 4000 organism signal system was used to record the rats' hemodynamic indices. Additionally, the heart weight was determined, and the cardiac remodeling index was calculated. HE and Masson's stains were utilized to perform histological analyses; the immunofluorescence was used to observe the microvessel density of myocardial tissue; the colorimetric method was used to determine the hydroxyproline content of cardiac tissue; the ELISA method was used to measure the plasma PGI2 content; and transmission electron microscopy was used to observe the ultrastructure of the myocardium. Results: A hyperdynamic circulation state, cardiac remodeling, decreased microvessel density and decreased plasma PGI2 content were each observed in the model group compared with the sham group, in which any changes in the above parameters were effectively reversed by MHBFC. Single-use Indo administration resulted in the progression of these pathophysiological changes; however, MHBFC prevented the worsening of these parameters. Conclusion: MHBFC significantly reverses pressure overload-induced cardiac remodeling, and its mechanism may partially contribute to the amelioration of endothelial cell function and the augmentation of PGI2 synthesis and secretion. [ABSTRACT FROM AUTHOR]

Aim: The primary objective of this study was to study the effects of 17-methoxyl-7-hydroxybenzene- furanchalcone (MHBFC) on pressure overload-induced cardiac remodeling in rats, as well as the endothelial mechanisms based on PGI2 Methods: Six weeks following surgery, rats were divided randomly into the following groups: a sham group, a model group, an MHBFC 12 mg/kg/day group (MHBFC 12), an indomethacin 2 mg/kg/day group (Indo 2), and an Indo 2+ MHBFC 12 group. The MS 4000 organism signal system was used to record the rats' hemodynamic indices. Additionally, the heart weight was determined, and the cardiac remodeling index was calculated. HE and Masson's stains were utilized to perform histological analyses; the immunofluorescence was used to observe the microvessel density of myocardial tissue; the colorimetric method was used to determine the hydroxyproline content of cardiac tissue; the ELISA method was used to measure the plasma PGI2 content; and transmission electron microscopy was used to observe the ultrastructure of the myocardium. Results: A hyperdynamic circulation state, cardiac remodeling, decreased microvessel density and decreased plasma PGI2 content were each observed in the model group compared with the sham group, in which any changes in the above parameters were effectively reversed by MHBFC. Single-use Indo administration resulted in the progression of these pathophysiological changes; however, MHBFC prevented the worsening of these parameters. Conclusion: MHBFC significantly reverses pressure overload-induced cardiac remodeling, and its mechanism may partially contribute to the amelioration of endothelial cell function and the augmentation of PGI2 synthesis and secretion. [ABSTRACT FROM AUTHOR]