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This study aimed to investigate the potential nephrotoxicity of icaritin and the underlying mechanism by in vitro-in vivo experiment technology combined with proteomics technology. First, icaritin showed a significant cytotoxic effect on HK-2 cells, which was accompanied by increased LDH and TNF-α in the supernatant, decreased protein expressions of Bcl-2 and increased Bax and enhanced apoptosis of HK-2 cells as measured by TUNEL staining. Moreover, icaritin induced obvious tubular damage and up-regulation of BUN and CRE levels in plasma in mice. Second, intracellular uptake of icaritin was considerably higher in hOAT1-HEK293 cells than in mock-HEK293 cells, suggesting that icaritin might accumulate in renal cells via OAT1 uptake. Importantly, icaritin caused significant changes in the PPAR signaling pathway in HK2 cells through proteomic analysis. Then, in vitro and in vivo results verified that icaritin significantly downregulated the protein expression of PPAR-α as well as downregulated APOB, ACSL3, ACSL4, and upregulated 5/12/15-HETE, implying that a lipid metabolism disorder was involved in the icaritin-induced nephrotoxicity. Finally, icaritin was found to increase the accumulation of iron and LPO levels while reducing the activity of GPX4, suggesting that ferroptosis was involved in the nephrotoxicity induced by icaritin. [ABSTRACT FROM AUTHOR]

Vancomycin (VCM)'s nephrotoxicity limits its application and therapeutic efficiency. The aim of this study was to determine the protective effect of rhein against VCM-induced nephrotoxicity (VIN). VIN models were established in rats and NRK-52E cells. Rhein up-regulated the expressions of renal organic anion transporter (Oat) 1, Oat3, organic cation transporter 2 (Oct2), multidrug resistance-associated protein 2 (Mrp2), mammal multidrug and toxin extrusion proteins 1 (Mate 1) and P-glycoprotein (P-gp) to facilitate the efflux of plasma creatinine, blood urea nitrogen (BUN), and plasma indoxyl sulfate. Rhein increased the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) to regulate the expression of Mrp2, P-gp, and Mate 1. The increased level of superoxide dismutase (SOD), decreased level of malondialdehyde (MDA) and reduced number of apoptosis cells were observed after treatment of rhein. Rhein decreased the number of apoptosis cells as well as increased the expression of B-cell lymphoma-2 (Bcl-2) and decreased expressions of Bcl-2-like protein 4 (Bax). ML385, as a typical inhibitor of Nrf2, reversed the protective effects of rhein in cells. Rhein oriented itself in the site of Keap1, inhibiting the Keap1-Nrf2 interaction. Rhein ameliorated VIN mainly through regulating the expressions of renal transporters and acting on Nrf2 pathway. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD), a metabolic disease, has received wide attention worldwide. However, there is no approved effective drug for NAFLD treatment. In the study, H&E and Oil Red O staining were employed to detect liver histopathological changes and the accumulation of lipid droplets. Quantitative real‐time PCR, Western blot, bioinformatics, luciferase assay, immunofluorescence staining, reactive oxygen species (ROS), and siRNA were used to further elucidate the mechanism of isoliquiritigenin (ISL) against NAFLD. The results showed that ISL significantly reduced the liver‐to‐body weight ratios and biochemical index. And the staining results showed that ISL remarkedly ameliorated liver histopathological changes of NAFLD. Furthermore, ISL significantly increased the levels of PPARα, CPT1α, and ACADS, which were involved in lipid metabolism, and inhibited the ROS, TNF‐α, IL‐1β, and IL‐6 expression by activating PGC‐1α. Bioinformatics and luciferase assay analysis confirmed that miR‐138‐5p might bind to PGC‐1α mRNA in NAFLD. Importantly, the expression of miR‐138‐5p was increased in the NAFLD, which was significantly decreased by ISL. In addition, the miR‐138‐5p inhibitor also promoted lipid metabolism and inhibited inflammatory response in NAFLD via PGC‐1α activation. The above results demonstrate that ISL alleviates NAFLD through modulating miR‐138‐5p/PGC‐1α‐mediated lipid metabolism and inflammatory reaction in vivo and in vitro. [ABSTRACT FROM AUTHOR]

Puerarin is an isoflavone isolated from Pueraria lobata (Willd.) Ohwi. In the present study, reversal effect and underlying mechanisms of puerarin on multidrug resistance (MDR) were investigated in K562/ADR cells. K562/ADR cells exhibited adriamycin (ADR) resistance and higher levels of MDR1 expression compared with K562 cells. Puerarin enhanced the chemosensitivity of K562/ADR cells and increased the ADR accumulation in K562/ADR cells. The expression levels of MDR1 were down‐regulated by puerarin in K562/ADR cells. Luciferase reporter assay further demonstrated the inhibitory effect of puerarin on TNF‐α‐induced NF‐κB activation. The phosphorylation of IκB‐α was significantly suppressed by puerarin. In silico docking analyses suggested that puerarin well matched with the active sites of IκB‐α. Moreover, a large number of autophagosomes were found in the cytoplasm of K562/ADR cells after puerarin treatment. The significant increase in LC3‐II and beclin‐1 was also observed, indicating autophagy induction by puerarin in K562/ADR cells. Puerarin induced cell cycle arrest and apoptosis in K562/ADR cells. Finally, puerarin inhibited phosphorylation of Akt and JNK. In conclusion, puerarin‐sensitized K562/ADR cells by downregulating MDR1 expression via inhibition of NF‐κB pathway and autophagy induction via Akt inhibition. [ABSTRACT FROM AUTHOR]

Rosmarinic acid (RA) is a water‐soluble phenolic compound extracted from Boraginaceae and Lamiaceae. This study was designed to investigate the role and mechanism of action of RA in improving nonalcoholic fatty liver disease (NAFLD). Male SD rats maintained on a high fat diet and L02 cells stimulated with oleic acid were treated with RA. Our results showed that RA significantly reduced total cholesterol, triglycerides, low‐density lipoprotein cholesterol, alanine aminotransferase, aspartate aminotransferase, and malondialdehyde levels and increased high‐density lipoprotein cholesterol, superoxide dismutase and adenosine triphosphate levels both in vivo and in vitro. Hematoxylin and eosin staining and oil red O staining showed that RA had a good lipid‐lowering effect and substantial protective effects on liver injury. Transmission electron microscopy and JC‐1 fluorescence results showed that RA could improve mitochondrial damage in hepatocytes. Additionally, flow cytometry results indicated that RA inhibited ROS generation and apoptosis in L02 cells. The impaired hepatocytes were restored by using RA in NAFLD models characterized by down‐regulating YAP1 and TAZ, meanwhile up‐regulating PPARγ and PGC‐1α. When YAP1 was over‐expressed, RA reduced the expression of YAP1; however, the action of RA was significantly blocked by silencing YAP1. The experimental results indicated that RA markedly alleviated NAFLD by repairing mitochondrial damage and regulating the YAP1/TAZ‐PPARγ/PGC‐1α signaling pathway. [ABSTRACT FROM AUTHOR]

Imipenem (Imp) is a widely used broad-spectrum antibiotic. However, renal adverse effects limit its clinical application. We previously reported that organic anion transporters (OATs) facilitated the renal transport of Imp and contributed its nephrotoxicity. Natural flavonoids exhibited renal protective effect. Here, we aimed to develop potent OAT inhibitors from traditional Chinese medicines (TCMs) and to evaluate its protective effect against Imp-induced nephrotoxicity. Among 50 TCMs, Tribuli Fructus, Platycladi Cacumen, and Lycopi Herba exhibited potent inhibition on OAT1/3. After screening their main components, Apigenin strongly inhibited Imp uptake by OAT1/3-HEK293 cells with IC50 values of 1.98 ± 0.36 μM (OAT1) and 2.29 ± 0.88 μM (OAT3). Moreover, Imp exhibited OAT1/3-dependent cytotoxicity, which was alleviated by Apigenin. Furthermore, Apigenin ameliorated Imp-induced nephrotoxicity in rabbits, and reduced the renal secretion of Imp. Apigenin inhibited intracellular accumulation of Imp and sequentially decreased the nephrocyte toxicity in rabbit primary proximal tubule cells (rPTCs). Apigenin, a flavone widely distributed in TCMs, was a potent OAT1/3 inhibitor. Through OAT inhibition, at least in part, Apigenin decreased the renal exposure of Imp and consequently protected against the nephrotoxicity of Imp. Apigenin can be used as a promising agent to reduce the renal adverse reaction of Imp in clinic. [ABSTRACT FROM AUTHOR]

Objectives: The study aimed to explore the effects of mouth breathing and hypoxia on the condyle of temporomandibular joint (TMJ) via two animal models. Methods: 24 four‐week‐old rats were randomly separated into three groups, consisting of eight control rats, eight intermittent hypoxia (IH) rats, and eight intermittent nasal obstruction (INO) rats. We use the IH model and the INO model to simulate children suffering from hypoxia and mouth breathing. After 16 days, the condyle of TMJ and surrounding white adipose tissue (WAT) and skeletal muscle tissue were obtained for further staining and qRT‐PCR. Finally, RNA‐seq was used to verify the results. Results: The intermittent hypoxia cannot significantly change the overall structure in the cause of short‐term hypoxia stimulation, but the intermittent nasal obstruction can alter the condyle, WAT, and muscle, while also introducing noticeable structural changes in tissue hypoxia and macrophage infiltration. Sequencing data verified these findings and also suggested that this process might involve the Hif‐1α/Vegf axis. Conclusions: Our findings reveal the very early structural impact of mouth breathing on condyle reconstruction in rat models, and hypoxia does not induce evident alteration on condyle. However, since these results are mainly focused on rats, further studies are needed to understand its effects on humans. [ABSTRACT FROM AUTHOR]

Background and Purpose: Diclofenac is a widely used nonsteroidal anti-inflammatory drug. However, adverse effects in the kidney limit its clinical application. The present study was aimed to evaluate the potential effect of cilastatin on diclofenac-induced acute kidney injury and to clarify the potential roles of renal organic anion transporters (OATs) in the drug-drug interaction between cilastatin and diclofenac.Experimental Approach: The effect of cilastatin was evaluated in diclofenac-induced acute kidney injury in mice. Human OAT1/3-transfected HEK293 cells and renal primary proximal tubule cells (RPTCs) were used to investigate OAT1/3-mediated transport and the cytotoxicity of diclofenac.Key Results: Cilastatin treatment decreased the pathological changes, renal dysfunction and elevated renal levels of oxidation products, cytokine production and apoptosis induced by diclofenac in mice. Moreover, cilastatin increased the plasma concentration and decreased the renal distribution of diclofenac and its glucuronide metabolite, diclofenac acyl glucuronide (DLF-AG). Similarly, cilastatin inhibited cytotoxicity and mitochondrial damage in RPTCs but did not change the intracellular accumulation of diclofenac. DLF-AG but not diclofenac exhibited OAT-dependent cytotoxicity and was identified as an OAT1/3 substrate. Cilastatin inhibited the intracellular accumulation and decreased the cytotoxicity of DLF-AG in RPTCs.Conclusion and Implications: Cilastatin alleviated diclofenac-induced acute kidney injury in mice by restoring the redox balance, suppressing inflammation, and reducing apoptosis. Cilastatin inhibited OATs and decreased the renal distribution of diclofenac and DLF-AG, which further ameliorated the diclofenac-induced nephrotoxicity in mice. Cilastatin can be potentially used in the clinic as a therapeutic agent to alleviate the adverse renal reaction to diclofenac. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinase‐9 (MMP‐9), or gelatinase B, has been hypothesized to be involved in the progression of atherosclerosis. In the arterial wall, accumulated macrophages secrete considerable amounts of MMP‐9 but its pathophysiological functions in atherosclerosis have not been fully elucidated. To examine the hypothesis that macrophage‐derived MMP‐9 may affect atherosclerosis, we created MMP‐9 transgenic (Tg) rabbits to overexpress the rabbit MMP‐9 gene under the control of the scavenger receptor A enhancer/promoter and examined their susceptibility to cholesterol diet‐induced atherosclerosis. Tg rabbits along with non‐Tg rabbits were fed a cholesterol diet for 16 and 28 weeks, and their aortic and coronary atherosclerosis was compared. Gross aortic lesion areas were significantly increased in female Tg rabbits at 28 weeks; however, pathological examination revealed that all the lesions of Tg rabbits fed a cholesterol diet for either 16 or 28 weeks were characterized by increased monocyte/macrophage accumulation and prominent lipid core formation compared with those of non‐Tg rabbits. Macrophages isolated from Tg rabbits exhibited higher infiltrative activity towards a chemoattractant, MCP‐1 in vitro and augmented capability of hydrolysing extracellular matrix in granulomatous tissue. Surprisingly, the lesions of Tg rabbits showed more advanced lesions with remarkable calcification in both aortas and coronary arteries. In conclusion, macrophage‐derived MMP‐9 facilitates the infiltration of monocyte/macrophages into the lesions thereby enhancing the progression of atherosclerosis. Increased accumulation of lesional macrophages may promote vascular calcification. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore whether rhein could enhance the effects of pemetrexed (PTX) on the therapy of non‐small‐cell lung cancer (NSCLC) and to clarify the associated molecular mechanism. Our study shows that rhein in combination with PTX could obviously increase the systemic exposure of PTX in rats, which would be mediated by the inhibition of organic anion transporters (OATs). Furthermore, the toxicity of PTX was significantly raised by rhein in A549 cells in a concentration‐dependent manner. Concomitant administration of rhein and PTX‐induced cell apoptosis compared with PTX alone in flow cytometry assays, which was further validated by the protein expressions of the apoptotic markers B‐cell lymphoma‐2/Bcl‐2‐associated x (Bcl‐2/Bax) and Cleaved‐Caspase3 (Cl‐Caspase3). Meanwhile, the results of monodansylcadaverine (MDC) dyeing experiments showed that PTX‐induced autophagy could be enhanced by combination therapy with rhein in A549 cells. Western blot analysis indicated that the synergistic effect of rhein on PTX‐mediated autophagy may be interrelated to PI3K–AKT–mTOR pathway inhibition and to the enhancement of p‐AMPK and light chain 3‐II (LC3‐II) protein levels. From these findings, it could be surmised that rhein enhanced the antitumor activity of PTX through influencing autophagy and apoptosis by modulating the PI3K–AKT–mTOR pathway and Bcl‐2 family of proteins in A549 cells. Our findings demonstrated that the potential application of rhein as a candidate drug in combination with PTX is promising for treatment of the human lung cancer. [ABSTRACT FROM AUTHOR]

Background and Purpose: Catalpol, a water-soluble active ingredient isolated from Rehmannia glutinosa, exhibits multiple pharmacological activities. However, the mechanism(s) underlying protection against renal injury by catalpol remains unknown.Experimental Approach: Adriamycin-induced kidney injury models associated with podocyte damage were employed to investigate the nephroprotective effects of catalpol. In vivo, TUNEL and haematoxylin-eosin staining was used to evaluate the effect of catalpol on kidney injury in mice. In vitro, effects of catalpol on podocyte damage induced by adriamycin was determined by elisa kit, flow cytometry, Hoechst 33342, and TUNEL staining. The mechanism was investigated by siRNA, EX527, and docking simulations.Key Results: In vivo, catalpol treatment significantly improved adriamycin-induced kidney pathological changes and decreased the number of apoptotic cells. In vitro, catalpol markedly decreased the intracellular accumulation of adriamycin and reduced the calcium ion level in podocytes and then attenuated apoptosis. Importantly, the regulatory effects of catalpol on sirtuin 1 (SIRT1), multidrug resistance-associated protein 2 (MRP2), and the TRPC6 channel were mostly abolished after incubation with SIRT1 siRNA or the SIRT1-specific inhibitor EX527. Furthermore, docking simulations showed that catalpol efficiently oriented itself in the active site of SIRT1, indicating a higher total binding affinity score than that of other SIRT1 activators, such as resveratrol, SRT2104, and quercetin.Conclusion and Implications: Taken together, our results suggest that catalpol exhibits strong protective effects against adriamycin-induced nephropathy by inducing SIRT1-mediated inhibition of TRPC6 expression and enhancing MRP2 expression. [ABSTRACT FROM AUTHOR]

Atherosclerosis (AS), a progressive disorder, is one of the tough challenges in the clinic. Scutellarin, an extract from Herba Erigerontis, is found to have oxygen‐free radicals scavenging effects and antioxidant effects. In this study, we aimed to investigate the anti‐AS effects of scutellarin is related to controlling the Hippo–FOXO3A and PI3K/AKT signal pathway. To establish an AS model, the rats in the scutellarin and model groups were intraperitoneally injected with vitamin D 3 and then fed a high‐fat diet for 12 weeks. In addition, in vitro angiotensin II‐induced apoptosis of human aortic endothelial cells (HAECs) were used to establish models. Scutellarin significantly reduced blood lipid levels and increased antioxidase levels in both models. Additionally, scutellarin inhibited reactive oxygen species generation and apoptosis in HAECs. The impaired vascular barrier function was restored by using scutellarin in AS rats and in HAECs cells characterized by inhibiting mammalian sterile‐20‐like kinases 1 (Mst1) phosphorylation, Yes‐associated protein (YAP) phosphorylation, forkhead box O3A (FOXO3A) phosphorylation at serine 207, nuclear translocation of FOXO3A, and upregulating protein expression of AKT and FOXO3A phosphorylation at serine 253. Scutellarin significantly reduced Bcl‐2 interacting mediator of cell death (Bim), caspase‐3, APO‐1, CD95 (Fas), and Bax: Bcl‐2‐associated X (Bax) levels and activated Bcl‐2: B‐cell lymphoma‐2 (Bcl‐2). Scutellarin also significantly inhibited the expression of Mst1, YAP, FOXO3A at the messenger RNA level. When Mst1 was overexpressed or phosphoinositide 3‐kinases suppressed, the effects of scutellarin were significantly blocked. In conclusion, the results of the present study suggest that scutellarin exerts protective effects against AS by inhibiting endothelial cell injury and apoptosis by regulating the Hippo–FOXO3A and PI3K/AKT signal pathways. [ABSTRACT FROM AUTHOR]

Glucocorticoid‐induced osteoporosis (GIO) is a secondary osteoporosis with extensive use of glucocorticoids (GCs). GCs can increase bone fragility and fracture via inhibiting osteoblastic proliferation and differentiation. Luteolin (LUT), a kind of plant flavonoid, has been reported to exhibit the antioxidant activity, but the effects of LUT on GIO still remain unclear. This study aimed to investigate the effects of LUT on GIO both in vivo and in vitro and elaborate the potential molecular mechanisms. LUT increased the superoxide dismutase activity, glutathione level and decreased reactive oxygen species (ROS) level and lactate dehydrogenase release in GIO. Meanwhile, LUT decreased caspase‐3, caspase‐9, and Bax protein expressions and increased Bcl‐2 protein expression in GIO. LUT increased the ratio of osteoprotegerin (OPG)/receptor activator of nuclear factor‐κB Ligand (RANKL) messenger RNA (mRNA) expression and mRNA expression levels of osteogenic markers, including runt‐related transcription factor 2, osterix, collagen type I, and osteocalcin. LUT also enhanced the extracellular signal‐regulated kinases (ERK) phosphorylation, glycogen synthase kinase 3β (GSK‐3β) phosphorylation, mRNA expression levels of lipoprotein‐receptor‐related protein 5 (Lrp‐5) and β‐catenin. Further study revealed that Lrp‐5 small interfering RNA (siRNA)and ERK‐siRNA reduced the effects of LUT on GSK‐3β phosphorylation, alkaline phosphatase (ALP) activity and the ratio of OPG/RANKL mRNA expression. Moreover, ERK‐siRNA decreased Lrp‐5 mRNA expression in vitro. These results indicated that LUT promoted proliferation by attenuating oxidative stress and promoted osteoblastic differentiation by regulating the ERK/Lrp‐5/GSK‐3β pathway in GIO. This study may bring to light the possible mechanisms involved in the action of LUT in GIO treatment, and benefit for further research on GIO. Luteolin (LUT) could inhibit osteoblastic apoptosis via inhibiting oxidative stress in glucocorticoid‐induced osteoporosis (GIO). Moreover, LUT could promote osteoblastic differentiation via the extracellular signal‐regulated kinases (ERK)/lipoprotein‐receptor‐related protein 5 (Lrp‐5)/glycogen synthase kinase 3β (GSK‐3β) signaling pathway in GIO. [ABSTRACT FROM AUTHOR]

Though the advancement of chemotherapy drugs alleviates the progress of cancer, long‐term therapy with anticancer agents gradually leads to acquired multidrug resistance (MDR), which limits the survival outcomes in patients. It was shown that dihydromyricetin (DMY) could partly reverse MDR by suppressing P‐glycoprotein (P‐gp) and soluble resistance‐related calcium‐binding protein (SORCIN) independently. To reverse MDR more effectively, a new strategy was raised, that is, circumventing MDR by the coadministration of DMY and ondansetron (OND), a common antiemetic drug, during cancer chemotherapy. Meanwhile, the interior relation between P‐gp and SORCIN was also revealed. The combination of DMY and OND strongly enhanced antiproliferative efficiency of adriamycin (ADR) because of the increasing accumulation of ADR in K562/ADR‐resistant cell line. DMY could downregulate the expression of SORCIN and P‐gp via the ERK/Akt pathways, whereas OND could not. In addition, it was proved that SORCIN suppressed ERK and Akt to inhibit P‐gp by the silence of SORCIN, however, not vice versa. Finally, the combination of DMY, OND, and ADR led to G2/M cell cycle arrest and apoptosis via resuming P53 function and restraining relevant proteins expression. These fundamental findings provided a promising approach for further treatment of MDR. Soluble resistance‐related calcium‐binding protein suppressed expression of P‐glycoprotein via ERK/Akt signaling pathways. Coadministration of dihydromyricetin and ondansetron could strongly enhance the antiproliferative efficiency of adriamycin (ADR) by promoting ADR‐induced G2/M cell cycle arrest and apoptosis. [ABSTRACT FROM AUTHOR]

Background and Purpose: Dioscin shows potent effects against cancers. We aimed to elucidate its pharmacological effects and mechanisms of action on hepatocellular carcinoma (HCC) in vivo and in vitro.Experimental Approach: Effects of dioscin were investigated in SMMC7721 and HepG2 cells, diethylnitrosamine-induced primary liver cancer in rats, and cell xenografts in nude mice. Isobaric tags for relative and absolution quantitation (iTRAQ)-based proteomics was used to find dioscin's targets and investigate its mechanism.Key Results: In SMMC7721 and HepG2 cells dioscin markedly inhibited cell proliferation and migration, induced apoptosis, autophagy, and DNA damage. It inhibited DEN-induced primary liver cancer in rats, markedly changed body weights and restored levels of α fetoprotein, alanine transaminase, aspartate transaminase, γ-glutamyltransferase, alkaline phosphatase, and Ki67. It also inhibited growth of xenografts in mice. In SMMC7721 cells, 191 differentially expressed proteins were found after dioscin, based on iTRAQ-based assay. TP53-inducible glycolysis and apoptosis regulator (TIGAR) was identified as being significantly down-regulated by dioscin. Dioscin induced cell apoptosis, autophagy, and DNA damage via increasing expression levels of p53, cleaved PARP, Bax, cleaved caspase-3/9, Beclin-1, and LC3 and suppressing those of Bcl-2, p-Akt, p-mammalian target of rapamycin (mTOR), CDK5, p-ataxia telangiectasia-mutated gene (ATM). The transfection of TIGAR siRNA into SMMC7721 cells and xenografts in nude mice further confirmed that the potent activity of dioscin against HCC is evoked by adjusting TIGAR-mediated inhibition of p53, Akt/mTOR, and CDK5/ATM pathways.Conclusions and Implications: The data suggest that dioscin has potential as a therapeutic, and TIGAR as a drug target for treating HCC. [ABSTRACT FROM AUTHOR]

A new class of thiodiphenylpyrimidine analogs (Thio‐DPPY) were synthesized as potent and selective EGFR T790M inhibitors to overcome gefitinib resistance in nonsmall cell lung cancer (NSCLC). This structural optimization led to the identification of two potent EGFRT790M/L858R inhibitors, 14a and 14e, which possess IC50 values of 27.5 and 9.1 nM, respectively. Moreover, compounds 14a (SI > 36.4) and 14e (SI > 109.9) exhibited high selectivity and low activity against the wild‐type EGFR (IC50 > 1,000 nM). In particular, compound 14a also displayed strong potency against EGFRT790M‐mutated H1975 cells (IC50 = 0.074 μM), but weak activity toward normal cells HBE (IC50 > 40 μM) and LO‐2 (IC50 = 9.891 μM). It is important that compound 14a (SI = 52.6) significantly improved the selectivity against mutant H1975 cells over wild‐type A431 cells than rociletinib (SI = 6.0), thus revealing its slight cell cytotoxicity. This study provides a promising Thio‐DPPY derivative as enhanced EGFR T790M inhibitor, and also revealed valuable clues for further optimization of DPPY scaffold to overcome NSCLC resistance. Thio‐DPPY derivatives as potent EGFRT790M inhibitors. Compounds 14a (27.5 nM) and 14e (6.1 nM) possess strong anti‐EGFRT790M enzymatic activity. 14a (SI = 52.6) significantly improved the activity and selectivity against mutant H1975 cells over wild‐type A431 cells than rociletinib (SI = 6.0). [ABSTRACT FROM AUTHOR]

Abstract: Oxidative stress and inflammatory response are well known to be involved in the pathogenesis of acute liver injury. This study was performed to examine the hepatoprotective effect of ginsenoside Rg1 (Rg1) against CCl4‐induced acute liver injury, and further to elucidate the involvement of Nrf2 signaling pathway in vivo and in vitro. Mice were orally administered Rg1 (15, 30, and 60 mg/kg) or sulforaphane (SFN) once daily for 1 week prior to 750 μL/kg CCl4 injection. The results showed that Rg1 markedly altered relative liver weights, promoted liver repair, increased the serum level of TP and decreased the serum levels of ALT, AST and ALP. Hepatic oxidative stress was inhibited by Rg1, as evidenced by the decrease in MDA, and increases in GSH, SOD, and CAT in the liver. Further research demonstrated that Rg1 suppressed liver inflammation response through repressing the expression levels of inflammation‐related genes including TNF‐α, IL‐1β, IL‐6, COX‐2, and iNOS. In addition, Rg1 enhanced antioxidative stress and liver detoxification abilities by up‐regulating Nrf2 and its target‐genes such as GCLC, GCLM, HO‐1, NQO1, Besp, Mrp2, Mrp3, Mrp4, and down‐regulating Cyp2e1. However, the changes in Nrf2 target‐genes, as well as ameliorative liver histology induced by Rg1 were abrogated by Nrf2 antagonist all‐transretinoic acid in vivo and Nrf2 siRNA in vitro. Overall, the findings indicated that Rg1 might be an effective approach for the prevention against acute liver injury by activating Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Background and Purpose: Intestinal ischaemia-reperfusion (II/R) injury is a serious clinical problem. Here we have investigated novel mechanisms and new drug targets in II/R injury by searching for microRNAs regulating such injury.Experimental Approach: We used hypoxia/reoxygenation (H/R) of IEC-6 cell cultures and models of II/R models in rats and mice. Microarray assays were used to identify target miRNAs from rat intestinal. Real-time PCR, Western blot and dual luciferase reporter assays, and agomir and antagomir in vitro and in vivo were used to assess the effects of the target miRNA on II/R injury.Key Results: The miR-351-5p was differentially expressed in our models and it targeted MAPK13 and sirtuin-6. This miRNA reduced levels of sirtuin-6 and AMP-activated protein kinase phosphorylation, and activated forkhead box O3 (FoxO3α) phosphorylation to cause oxidative stress. Also, miR-351-5p markedly reduced MAPK13 level, activated polycystic kidney disease 1/NF-κB signal and increased NF-κB (p65). Moreover, miR-351-5p up-regulated levels of Bcl2-associated X, cytochrome c, apoptotic peptidase activating factor 1, cleaved-caspase 3 and cleaved-caspase 9 by reducing sirtuin-6 levels to promote apoptosis. In addition, miR-351-5p mimic in IEC-6 cells and agomir in mice aggravated these effects, and miR-351-5p inhibitor and antagomir in mice alleviated these actions.Conclusions and Implications: Our data showed that miR-351-5p aggravated II/R injury by promoting intestinal mucosal oxidative stress, inflammation and apoptosis by targeting MAPK13 and sirtuin-6.These data provide new insights into the mechanisms regulating II/R injury, and of miR-351-5p could be considered as a novel therapeutic target for such injury. [ABSTRACT FROM AUTHOR]

Recently, a new target Ca2+-binding protein SORCIN was reported to participate in multidrug resistance (MDR)in cancer.Herewe aim to investigatewhether dihydromyricetin (DMY), a dihydroflavonol compound with anti-inflamatory, anti-oxidant, anti-bacterial and anti-tumor actions, reverses MDR in MCF-7/ADR and K562/ADR and to elucidate its potential molecular mechanism. DMY enhanced cytotoxicity of adriamycin (ADR) by downregulatingMDR1 mRNA and P-gp expression through MAPK/ERK pathway and also inhibiting the function of P-gp significantly.Meanwhile,DMYdecreasedmRNA and protein expression of SORCIN, which resulted in elevating intracellular free Ca2+. Finally, we investigated co-administration ADR with DMY remarkably increased ADR-induced apoptosis. Further study showed DMY elevated ROS levels and caspase-12 protein expression, which signal apoptosis in endoplasmic reticulum. At the same time, proteins related to mitochondrial apoptosis were also changed such as Bcl-2, Bax, caspase-3, caspase-9, and PARP. Finally, nudemicemodel also demonstrated thatDMY strengthened anti-tumor activity of ADR in vivo. In conclusion, DMY reverses MDR by downregulating P-gp, SORCIN expression and increasing freeCa2+, aswell as, inducing apoptosis inMCF-7/ ADR and K562/ADR. These fundamental findings provide evidence for further clinical research in application of DMY as an assistant agent in the treatment of cancer. [ABSTRACT FROM AUTHOR]

Abstract: Background and Aim: Nonalcoholic fatty liver disease (NAFLD) has become a major health concern worldwide. The present study was designed to investigate the effects of calycosin against high‐fat diet (HFD)‐induced NAFLD in mice. Methods: C57BL/6 J male mice were fed with HFD to induce NAFLD model and treated with or without calycosin for 12 weeks. The levels of ALT, AST, insulin, and adiponectin were measured using biochemical methods. Hemotoxylin and eosin staining and Oil Red O staining were used to determine the liver histopathology changes and measure the degree of lipid accumulation respectively. Glucose tolerance tests and insulin tolerance tests were performed followed by quantitative insulin sensitivity check index determination. Western blot and quantitative real‐time polymerase chain reaction were used to explore the potential mechanism involved in the beneficial effects of calycosin. Results: Calycosin effectively decreased the levels of ALT and AST, increased the levels of adiponectin and insulin. Hemotoxylin and eosin staining indicated calycosin treatment remarkably improved liver injury. Oil Red O staining indicated calycosin treatment remarkably improved lipid accumulation. Quantitative insulin sensitivity check index in HFD fed mice was significantly lower than in the standard chow fed mice. Further, calycosin suppressed phosphoenolpyruvate carboxykinase, glucose‐6‐phosphatase, sterol‐regulatory element binding protein 1c, and FASN involved in gluconeogenesis and triglyceride synthesis. Calycosin increased glycogen synthase kinase 3 beta, glucose transporter 4, and phosphorylated insulin receptor substrates 1 and 2 expressions involved in glucose metabolism. The aforementioned beneficial effects of calycosin against HFD‐induced NAFLD may be attributed to farnesoid X receptor activation. Conclusion: Calycosin could produce the favorable effects against HFD‐induced NAFLD in mice. [ABSTRACT FROM AUTHOR]

Virus-specific cytotoxic T lymphocytes contribute to the control of virus infections including those caused by influenza viruses. However, during the evolution of influenza A viruses, variations in cytotoxic T lymphocytes epitopes have been observed and it will affect the recognition by virus-specific cytotoxic T lymphocytes and the human virus-specific cytotoxic T lymphocytes response in vitro. Here, to gain further insights into the molecular mechanism of the virus-specific cytotoxic T lymphocytes immunity, the class I major histocompatibility complex-encoded HLA-B*3501 protein with six different NP418-426 antigenic peptides emerging from 1918 to 2009 pandemic influenza A virus were studied by molecular dynamics simulation. Dynamical and structural properties (such as atomic fluctuations, solvent-accessible surface areas, binding free energy), based on the solvated protein-peptide complexes, were compared. Free energy calculations emphasized the important role of the secondary anchors (positions 2 and 9) in influencing the binding of MHC-I with antigenic non-apeptides. Furthermore, major interactions with peptides were gained from HLA-B*3501 residues: Tyr7, Ile66, Lys146, Trp147, and Tyr159. Detailed analysis could help to understand how different NP418-426 mutants effectively bind with the HLA-B*3501. [ABSTRACT FROM AUTHOR]

Objective: Increased enzymatic activity of matrix metalloproteinases (MMPs) may promote the progression of rheumatoid arthritis (RA). We undertook this study to investigate the expression and localization of human macrophage elastase (MMP-12) in synovial tissue from RA patients and to compare MMP-12 levels in the synovial tissue and synovial fluid of RA patients with the corresponding levels in patients with osteoarthritis (OA)., Methods: We obtained synovial tissues from 23 RA patients and 29 OA patients and analyzed MMP-12 expression using immunohistochemistry, Western and Northern blotting analyses, and zymography. Furthermore, we quantified MMP-12 levels in synovial fluid by Western blotting and zymography., Results: Northern blotting analysis demonstrated that RA synovial tissue contained higher levels of MMP-12 messenger RNA than did OA synovial tissue. Western blotting revealed that MMP-12 proteins were consistently and markedly increased in RA synovial tissue compared with OA synovial tissue. A greater amount of immunoreactive proteins corresponding to catalytic forms of MMP-12 was present in RA synovial tissue and synovial fluid, and the MMP-12 proteins exhibited caseinolytic activity in vitro. Immunohistochemical staining showed that the major cells expressing MMP-12 were synovial lining cells, many of which were inflammatory macrophages., Conclusion: These results establish a possible mechanism by which macrophage-derived MMP-12 may play an important role in the destructive process in RA. Inhibition of MMP-12 may be a potential modality for the treatment of RA., (Copyright 2004 American College of Rheumatology)