Thymoquinone affects hypoxia-inducible factor-1αexpression in pancreatic cancer cells via HSP90 and PI3K/AKT/mTOR pathways

BACKGROUND Pancreatic cancer(PC)is associated with some of the worst prognoses of all major cancers.Thymoquinone(TQ)has a long history in traditional medical practice and is known for its anti-cancer,anti-inflammatory,anti-fibrosis and antioxidant pharmacological activities.Recent studies on hypoxia-inducible factor-1α(HIF-1α)and PC have shown that HIF-1αaffects the occurrence and development of PC in many aspects.In addition,TQ could inhibit the development of renal cancer by decreasing the expression of HIF-1α.Therefore,we speculate whether TQ affects HIF-1αexpression in PC cells and explore the mechanism.AIM To elucidate the effect of TQ in PC cells and the regulatory mechanism of HIF-1αexpression.METHODS Cell counting kit-8 assay,Transwell assay and flow cytometry were performed to detect the effects of TQ on the proliferative activity,migration and invasion ability and apoptosis of PANC-1 cells and normal pancreatic duct epithelial(hTERTHPNE)cells.Quantitative real-time polymerase chain reaction and western blot assay were performed to detect the expression of HIF-1αmRNA and protein in PC cells.The effects of TQ on the HIF-1αprotein initial expression pathway and ubiquitination degradation in PANC-1 cells were examined by western blot assay and co-immunoprecipitation.RESULTS TQ significantly inhibited proliferative activity,migration,and invasion ability and promoted apoptosis of PANC-1 cells;however,no significant effects on hTERT-HPNE cells were observed.TQ significantly reduced the mRNA and protein expression levels of HIF-1αin PANC-1,AsPC-1,and BxPC-3 cells.TQ significantly inhibited the expression of the HIF-1αinitial expression pathway(PI3K/AKT/mTOR)related proteins,and promoted the ubiquitination degradation of the HIF-1αprotein in PANC-1 cells.TQ had no effect on the hydroxylation and von Hippel Lindau protein mediated ubiquitination degradation of the HIF-1αprotein but affected the stability of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90,thus promoting its ubiquitination degradation.CONCLUSION The regulatory mechanism of TQ on HIF-1αprotein expression in PC cells was mainly to promote the ubiquitination degradation of the HIF-1αprotein by inhibiting the interaction between HIF-1αand HSP90;Secondly,TQ reduced the initial expression of HIF-1αprotein by inhibiting the PI3K/AKT/mTOR pathway.

Prevention and treatment of hypoxia-induced colorectal cancer damage in albino Wister rats

Background:In the early metastasis of colon cancer,cancer cells detach,migrate,and infiltrate surrounding tissues,including lymph vessels and blood vessels.Tumor heterogeneity arises from both tumor cells and distinct microenvironments.Maldistribution of blood vessels,creates hypoxic regions within the tumors,fostering cancer stem cell-like properties due to reduced oxygen and nutrient supply.Under hypoxia,tumor cells shift to a glycolytic pathway,producing more lactic acid that acidifies the microenvironment and leads to unstable heart rate variability(HRV)factors,weight disparity,and a higher incidence of aberrant crypt foci(ACF).These hypoxic-induced parameters promote cancer cell invasion,increase radiation resistance,and facilitate cancer cell migration.Methods:In this study,we induced hypoxia-preneoplastic colon damage in albino Wister rats by administrating 1,2-dimethyl hydrazine(DMH).After successfully creating a hypoxic environment in albino Wister rats,resulting in preneoplastic colon damage,we randomly allocated Wistar albino rats into seven groups,each containing 8 animals,and conducted a 6-week study.Group 1-Normal control(administered 1 mM EDTA+saline,2 ml/kg/day,p.o.);group 2-Toxic control(administered DMH,30 mg/kg/week,s.c.);group 3-Standard treatment(DMH,30 mg/kg/week,s.c.for 6 weeks),followed by 5-fluorouracil and Leucovorin(25 mg/kg each on 1^(st),3^(rd),7^(th),and 10^(th) days,i.p.after 6 weeks administration of DMH);group 4-Low dose of P1(DMH,30 mg/kg/week,s.c.+P1,2 mg/kg,i.v.,weekly for 3 weeks);group 5-High dose P1(DMH,30 mg/kg/week,s.c.+P1,4 mg/kg,i.v.,weekly for 3 weeks),group 6-Low dose of P2(DMH,30 mg/kg/week,s.c.,+P2,2 mg/kg,i.v.,weekly for 3 weeks),group 7-High dose of P2(DMH,30 mg/kg/week,s.c.,+P2,4 mg/kg,i.v.weekly for 3 weeks).Results:DMH-treated rats exhibited alterations in HRV factors,weight disparity,elevated gastric pH,increased total acidity,a higher incidence of ACF,and changes in antioxidant markers(TBARs,SOD,catalase,GSH).Brightfield microscopy at 40x magnification revealed the presence of large crypts within aberrant crypt foci in the toxic control group.Conclusion:Treatment groups P1 and P2 containing triazine derivatives initiated proteasomal degradation of Hypoxia Inducible Factor-1α(HIF-1α)by activating Prolyl Hydroxylase(PHDs)pathways.HIF-1αunder a hypoxic environment is responsible for activating a multitude of genes involved in angiogenesis,metastasis,invasiveness,pH changes,metabolic reprogramming,stem cell maintenance,resistance to radiation,and downstream regulation of the immune system.Treatment with P1 and P2 groups helped minimize the ACF count and restored HRV factors,weight disparity,pH levels,total acidity,and oxidative balance.Our findings emphasize the potential role of 1,2,4-triazine derivatives in suppressing hypoxia-induced colon carcinogenesis.

Cell metabolism pathways involved in the pathophysiological changes of diabetic peripheral neuropathy

Diabetic peripheral neuropathy is a common complication of diabetes mellitus.Elucidating the pathophysiological metabolic mechanism impels the generation of ideal therapies.However,existing limited treatments for diabetic peripheral neuropathy expose the urgent need for cell metabolism research.Given the lack of comprehensive understanding of energy metabolism changes and related signaling pathways in diabetic peripheral neuropathy,it is essential to explore energy changes and metabolic changes in diabetic peripheral neuropathy to develop suitable treatment methods.This review summarizes the pathophysiological mechanism of diabetic peripheral neuropathy from the perspective of cellular metabolism and the specific interventions for different metabolic pathways to develop effective treatment methods.Various metabolic mechanisms(e.g.,polyol,hexosamine,protein kinase C pathway)are associated with diabetic peripheral neuropathy,and researchers are looking for more effective treatments through these pathways.

Calculus bovis inhibits M2 tumor-associated macrophage polarization via Wnt/β-catenin pathway modulation to suppress liver cancer

BACKGROUND Calculus bovis(CB),used in traditional Chinese medicine,exhibits anti-tumor effects in various cancer models.It also constitutes an integral component of a compound formulation known as Pien Tze Huang,which is indicated for the treatment of liver cancer.However,its impact on the liver cancer tumor microenvironment,particularly on tumor-associated macrophages(TAMs),is not well understood.AIM To elucidate the anti-liver cancer effect of CB by inhibiting M2-TAM polarization via Wnt/β-catenin pathway modulation.METHODS This study identified the active components of CB using UPLC-Q-TOF-MS,evaluated its anti-neoplastic effects in a nude mouse model,and elucidated the underlying mechanisms via network pharmacology,transcriptomics,and molecular docking.In vitro assays were used to investigate the effects of CB-containing serum on HepG2 cells and M2-TAMs,and Wnt pathway modulation was validated by real-time reverse transcriptase-polymerase chain reaction and Western blot analysis.RESULTS This study identified 22 active components in CB,11 of which were detected in the bloodstream.Preclinical investigations have demonstrated the ability of CB to effectively inhibit liver tumor growth.An integrated approach employing network pharmacology,transcriptomics,and molecular docking implicated the Wnt signaling pathway as a target of the antineoplastic activity of CB by suppressing M2-TAM polarization.In vitro and in vivo experiments further confirmed that CB significantly hinders M2-TAM polarization and suppresses Wnt/β-catenin pathway activation.The inhibitory effect of CB on M2-TAMs was reversed when treated with the Wnt agonist SKL2001,confirming its pathway specificity.CONCLUSION This study demonstrated that CB mediates inhibition of M2-TAM polarization through the Wnt/β-catenin pathway,contributing to the suppression of liver cancer growth.

Timosaponin AⅢ induces drug-metabolizing enzymes by activating constitutive androstane receptor (CAR) via dephosphorylation of the EGFR signaling pathway

The current study aimed to assess the effect of timosaponin AⅢ(T-AⅢ)on drug-metabolizing enzymes during anticancer therapy.The in vivo experiments were conducted on nude and ICR mice.Following a 24-day administration of T-AⅢ,the nude mice exhibited an induction of CYP2B10,MDR1,and CYP3A11 expression in the liver tissues.In the ICR mice,the expression levels of CYP2B10 and MDR1 increased after a three-day T-AⅢ administration.The in vitro assessments with HepG2 cells revealed that T-AⅢ induced the expression of CYP2B6,MDR1,and CYP3A4,along with constitutive androstane receptor(CAR)activation.Treatment with CAR siRNA reversed the T-AⅢ-induced increases in CYP2B6 and CYP3A4 expression.Furthermore,other CAR target genes also showed a significant increase in the expression.The up-regulation of murine CAR was observed in the liver tissues of both nude and ICR mice.Subsequent findings demonstrated that T-AⅢ activated CAR by inhibiting ERK1/2 phosphorylation,with this effect being partially reversed by the ERK activator t-BHQ.Inhibition of the ERK1/2 signaling pathway was also observed in vivo.Additionally,T-AⅢ inhibited the phosphorylation of EGFR at Tyr1173 and Tyr845,and suppressed EGF-induced phosphorylation of EGFR,ERK,and CAR.In the nude mice,T-AⅢ also inhibited EGFR phosphorylation.These results collectively indicate that T-AⅢ is a novel CAR activator through inhibition of the EGFR pathway.

Enterogenic Stenotrophomonas maltophilia migrates to the mammary gland to induce mastitis by activating the calcium-ROS-AMPK-mTOR-autophagy pathway

Background Mastitis is an inflammatory disease of the mammary gland that has serious economic impacts on the dairy industry and endangers food safety.Our previous study found that the body has a gut/rumen-mammary gland axis and that disturbance of the gut/rumen microbiota could result in‘gastroenterogenic mastitis'.However,the mechanism has not been fully clarified.Recently,we found that long-term feeding of a high-concentrate diet induced mastitis in dairy cows,and the abundance of Stenotrophomonas maltophilia(S.maltophilia)was significantly increased in both the rumen and milk microbiota.Accordingly,we hypothesized that‘gastroenterogenic mastitis'can be induced by the migration of endogenous gut bacteria to the mammary gland.Therefore,this study investigated the mechanism by which enterogenic S.maltophilia induces mastitis.Results First,S.maltophilia was labelled with superfolder GFP and administered to mice via gavage.The results showed that treatment with S.maltophilia promoted the occurrence of mastitis and increased the permeability of the blood-milk barrier,leading to intestinal inflammation and intestinal leakage.Furthermore,tracking of ingested S.maltophilia revealed that S.maltophilia could migrate from the gut to the mammary gland and induce mastitis.Subsequently,mammary gland transcriptome analysis showed that the calcium and AMPK signalling pathways were significantly upregulated in mice treated with S.maltophilia.Then,using mouse mammary epithelial cells(MMECs),we verified that S.maltophilia induces mastitis through activation of the calcium-ROS-AMPK-mTOR-autophagy pathway.Conclusions In conclusion,the results showed that enterogenic S.maltophilia could migrate from the gut to the mammary gland via the gut-mammary axis and activate the calcium-ROS-AMPK-mTOR-autophagy pathway to induce mastitis.Targeting the gut-mammary gland axis may also be an effective method to treat mastitis.

Myricetin induces M2 macrophage polarization to alleviate renal tubulointerstitial fibrosis in diabetic nephropathy via PI3K/Akt pathway

BACKGROUND Development of end-stage renal disease is predominantly attributed to diabetic nephropathy(DN).Previous studies have indicated that myricetin possesses the potential to mitigate the pathological alterations observed in renal tissue.Never-theless,the precise molecular mechanism through which myricetin influences the progression of DN remains uncertain.AIM To investigate the effects of myricetin on DN and explore its potential therapeutic mechanism.METHODS Db/db mice were administered myricetin intragastrically on a daily basis at doses of 50 mg/kg or 100 mg/kg for a duration of 12 wk.Subsequently,blood and urine indexes were assessed,along with examination of renal tissue pathology.Kidney morphology and fibrosis were evaluated using various staining techniques including hematoxylin and eosin,periodic acid–Schiff,Masson’s trichrome,and Sirius-red.Additionally,high-glucose culturing was conducted on the RAW 264.7 cell line,treated with 25 mM myricetin or co-administered with the PI3K/Akt inhibitor LY294002 for a period of 24 h.In both in vivo and in vitro settings,quantification of inflammation factor levels was conducted using western blotting,real-time qPCR and ELISA.RESULTS In db/db mice,administration of myricetin led to a mitigating effect on DN-induced renal dysfunction and fibrosis.Notably,we observed a significant reduction in expressions of the kidney injury markers kidney injury molecule-1 and neutrophil gelatinase associated lipocalin,along with a decrease in expressions of inflammatory cytokine-related factors.Furthermore,myricetin treatment effectively inhibited the up-regulation of tumor necrosis factor-alpha,interleukin-6,and interluekin-1βinduced by high glucose in RAW 264.7 cells.Additionally,myricetin modulated the M1-type polarization of the RAW 264.7 cells.Molecular docking and bioinformatic analyses revealed Akt as the target of myricetin.The protective effect of myricetin was nullified upon blocking the polarization of RAW 264.7 via inhibition of PI3K/Akt activation using LY294002.CONCLUSION This study demonstrated that myricetin effectively mitigates kidney injury in DN mice through the regulation of macrophage polarization via the PI3K/Akt signaling pathway.

Cyanidin-3-glucoside protects the photooxidative damage of retinal pigment epithelium cells by regulating sphingolipid signaling and inhibiting MAPK pathway

Cyanidin-3-glucoside(C3G)is the most common anthocyanin in dark grains and berries and is a food functional factor to improve visual health.However,the mechanisms of C3G on blue light-induced retinal pigment epithelial(RPE)cell photooxidative damage needs further exploration.We investigated the effects of C3G on blue light-irradiated A2E-containing RPE cells and explored whether sphingolipid,mitogen-activated protein kinase(MAPK),and mitochondria-mediated pathways are involved in this mechanism.Blue light irradiation led to mitochondria and lysosome damage in RPE cells,whereas C3G preserved mitochondrial morphology and function and maintained the lysosomal integrity.C3G suppressed the phosphorylation of JNK and p38 MAPK and mitochondria-mediated pathways to inhibit RPE cell apoptosis.Lipidomics data showed that C3G protected RPE cells against blue light-induced lipid peroxidation and apoptosis by maintaining sphingolipids balance.C3G significantly inhibited ceramide(Cer d18:0/15:0,Cer d18:0/16:0 and Cer d18:0/18:0)accumulation and elevated galactosylceramide(GalCer d18:1/15:0 and GalCer d18:1/16:0)levels in the irradiated A2E-containing RPE cells.Furthermore,C3G attenuated cell membrane damage by increasing phosphatidylcholine and phosphatidylserine levels.C3G inhibited apoptosis and preserved the structure of mitochondria and lysosome by regulating sphingolipid signaling and suppression of MAPK activation in RPE cells.Thus,dietary supplementation of C3G prevents retinal photooxidative damage.

Silencing of peroxiredoxin 2 suppresses proliferation and Wnt/β-catenin pathway,and induces senescence in hepatocellular carcinoma

Hepatocellular carcinoma(HCC),a common malignancy worldwide,still lacks effective clinical treatment.The study aimed to investigate the oncogenes that affect the progression of HCC and their possible mechanisms.In our study,we initially confirmed a higher level of PRDX2 in the bile of HCC patients compared to those with choledocholithiasis by 2-DE,LC-MS,and ELISA.Subsequently,we demonstrated the high expression of peroxiredoxin 2(PRDX2)in HCC based on the TCGA database and clinical sample analysis.Furthermore,PRDX2 overexpression enhanced the viability of HCC cells.And PRDX2 silencing induced senescence of HCC cells.In vivo,knockdown of PRDX2 significantly reduced the weight of xenograft tumors.PRDX2 also was found to activate the Wnt/β-catenin pathway by inducingβ-catenin nuclear translocation.Consequently,we proved that silencing PRDX2 could inhibit proliferation and Wnt/β-catenin pathway while promoting senescence in HCC cells.

Activation of the wnt/β-catenin/CYP1B1 pathway alleviates oxidative stress and protects the blood-brain barrier under cerebral ischemia/reperfusion conditions

Accumulating evidence suggests that oxidative stress and the Wnt/β-catenin pathway participate in stroke-induced disruption of the blood-brain barrier.However,the potential links between them following ischemic stroke remain largely unknown.The present study found that cerebral ischemia leads to oxidative stress and repression of the Wnt/β-catenin pathway.Meanwhile,Wnt/β-catenin pathway activation by the pharmacological inhibito r,TWS119,relieved oxidative stress,increased the levels of cytochrome P4501B1(CYP1B1)and tight junction-associated proteins(zonula occludens-1[ZO-1],occludin and claudin-5),as well as brain microvascular density in cerebral ischemia rats.Moreove r,rat brain microvascular endothelial cells that underwent oxygen glucose deprivation/reoxygenation displayed intense oxidative stress,suppression of the Wnt/β-catenin pathway,aggravated cell apoptosis,downregulated CYP1B1and tight junction protein levels,and inhibited cell prolife ration and migration.Overexpression ofβ-catenin or knockdown ofβ-catenin and CYP1B1 genes in rat brain mic rovascular endothelial cells at least partly ameliorated or exacerbated these effects,respectively.In addition,small interfering RNA-mediatedβ-catenin silencing decreased CYP1B1 expression,whereas CYP1B1 knoc kdown did not change the levels of glycogen synthase kinase 3β,Wnt-3a,andβ-catenin proteins in rat brain microvascular endothelial cells after oxygen glucose deprivatio n/reoxygenation.Thus,the data suggest that CYP1B1 can be regulated by Wnt/β-catenin signaling,and activation of the Wnt/β-catenin/CYP1B1 pathway contributes to alleviation of oxidative stress,increased tight junction levels,and protection of the blood-brain barrier against ischemia/hypoxia-induced injury.

Amitriptyline inhibits NLRP3 inflammasome activation via the ASM/CE pathway in a cell model of NAFLD

Background:Nonalcoholic fatty liver disease(NAFLD)is a global health concern with the acid sphingomyelinase(ASM)/ceramide(CE)pathway and the NOD-like receptor family,pyrin domain-containing protein 3(NLRP3)inflammasome identified as pivotal players in lipid disorders and inflammation.This study explores the interaction mechanism between the ASM/CE pathway and NLRP3 in NAFLD cell models,aiming to understand the impact of amitriptyline(Ami),an ASM inhibitor,on lipid deposition and hepatocyte injury by regulating the ASM/CE-NLRP3 pathway.Methods:HepG2 and HL-7702 cells were exposed to free fatty acids(FFAs)to establish the NAFLD model.The cells were divided into 5 groups:control group,model group,Ami group,tumor necrosis factoralpha(TNF-α)group,and Ami+TNF-αgroup.Intracellular lipid droplets were visualized using Oil Red O staining,and Western blot analysis quantified ASM,NLRP3,and caspase 1 protein expression.Enzyme linked immunosorbent assay(ELISA)was measured CE and ASM levels,while qRT-PCR assessed mRNA expression.The apoptotic rate was evaluated by flow cytometry(FCM).Results:Following FFAs incubation,significant increases in ASM and CE levels were observed in HepG2 and HL-7702 cells,accompanied by elevated expression of NLRP3,and caspase 1,and IL-1β.TNF-αtreatment further amplified these indicators.Ami demonstrated a reduction in lipid deposition,suppressed ASM/CE pathway activation,downregulated NLRP3 and caspase 1 expression,and improved apoptosis.Additionally,MCC950,a selective inhibitor of the NLRP3,mitigated NLRP3,caspase 1,and IL-1βexpression,alleviating lipid deposition and apoptosis in the NAFLD cell model.Conclusion:The ASM/CE-NLRP3 pathway in NAFLD cells promotes hepatocyte steatosis,inflammation,and cell damage.Ami emerges as a promising therapeutic agent by inhibiting the ASM/CE-NLRP3 pathway,underscoring its potential as a key target for NAFLD treatment.

Downregulation of Serum PTEN Expression in Mercury-Exposed Population and PI3K/AKT Pathway-Induced Inflammation

Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by ELISA.Results Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 expression.Similarly, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 levels.Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.

Hypoglycemic mechanism of Tegillarca granosa polysaccharides on type 2 diabetic mice by altering gut microbiota and regulating the PI3K-akt signaling pathwaye

Type 2 diabetes mellitus(T2DM)is a complex metabolic disease threatening human health.We investigated the effects of Tegillarca granosa polysaccharide(TGP)and determined its potential mechanisms in a mouse model of T2DM established through a high-fat diet and streptozotocin.TGP(5.1×10^(3) Da)was composed of mannose,glucosamine,rhamnose,glucuronic acid,galactosamine,glucose,galactose,xylose,and fucose.It could significantly alleviate weight loss,reduce fasting blood glucose levels,reverse dyslipidemia,reduce liver damage from oxidative stress,and improve insulin sensitivity.RT-PCR and Western blotting indicated that TGP could activate the phosphatidylinositol-3-kinase/protein kinase B signaling pathway to regulate disorders in glucolipid metabolism and improve insulin resistance.TGP increased the abundance of Allobaculum,Akkermansia,and Bifidobacterium,restored the microbiota abundance in the intestinal tracts of mice with T2DM,and promoted short-chain fatty acid production.This study provides new insights into the antidiabetic effects of TGP and highlights its potential as a natural hypoglycemic nutraceutical.

Danggui Shaoyao powder improves hepatic lipid metabolism in atherosclerosis mice via PPARγ-LXRα-ABCA1 pathway regulation

Objective:To observe the effects of Danggui Shaoyao powder(DSP)on hepatic lipid metabolism and further explore its mechanism of action by peroxisome proliferator-activated receptor(PPARγ)-liver X receptor(LXRα)-adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1)pathway regulation.Methods: Eight C57BL/6J male mice were selected as the control group,and 24 ApoE^(−/−)male mice were randomly divided into the atherosclerosis model(AS)group,atorvastatin calcium(AC)group,and DSP group(n=8 each group).To establish an AS model,ApoE^(−/−)mice were fed a high-fat diet for 16 weeks.Pathologic changes in the aortic vasculature and liver were identified using Oil Red O staining.Triglyceride(TG),cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C)levels were determined in the livers using a single-reagent GPO-PAP method.Fluorescence quantitative polymerase chain reaction and western blot were used to observe and evaluate the mRNA and protein expression of the PPARγ-LXRα-ABCA1 intermediates in the liver.Results: After 16 weeks of a high-fat diet,ApoE^(−/−)mice showed more Oil Red O staining in the aorta and liver compared to the CONT group.Compared to the AS group,the DSP and AC treatment reduced aortic plaque and hepatic lipid deposition to varying degrees.Furthermore,DSP significantly reduced the hepatic lipid area in ApoE^(−/−)mice(P<.001)and decreased the levels of TG,TC,and LDL-C in liver(P<.001,P=.027,P<.001,respectively).DSP also significantly increased the levels of PPARγ,LXRα,ABCA1,and ABCG1 mRNA expression,as well as the PPARγ,LXRα,ABCA1,and ABCG1 protein expression in liver.Conclusion: DSP improved hepatic lipid metabolism via PPARγ-LXRα-ABCA1 pathway modulation for AS treatment.

Apolipoprotein A1 suppresses the hypoxia-induced angiogenesis of human retinal endothelial cells by targeting PlGF

AIM:To investigate the anti-angiogenic effect of apolipoprotein A1(apoA1)on primary human retinal vascular endothelial cells(HRECs)and explore the possible mechanism.METHODS:The primary HRECs were transfected with apoA1-GFP recombinant lentiviral and were compared with cells undergoing transfection with empty lentiviral vectors.Hypoxia chambers were used to simulate the anoxic environment of cells under pathological condition.The concentrations of secreted vascular endothelial growth factor(VEGF)and placental growth factor(PlGF)were measured by enzyme-linked immunosorbent assay(ELISA).Cell migration ability was detected by wound healing assay.The sprouting of HRECs was determined by tube formation assay.The protein levels of extracellular signal regulated kinase 1/2(ERK1/2)and phosphor ylated ERK1/2(p-ERK1/2)were measured by Western blot.RESULTS:Overexpressed apoA1 in hypoxia-induced HRECs significantly suppressed PlGF(0.67±0.10 folds,P=0.007).Overexpressed apoA1 also attenuated hypoxiainduced cell migration(0.32±0.11 folds,P<0.0001),tube formation(0.66±0.01 folds,P<0.0001)and the phosphorylation levels of ERK(0.6±0.11 folds,P=0.025).Pretreatment of mitogen-activated protein kinase kinase(MEK)inhibitor(U0126)further reduced the PlGF and angiogenesis in hypoxia-induced HRECs.CONCLUSION:ApoA 1 inhibits the angiogenesis at least in part by inactivating ERK1/2 in hypoxia-induced HRECs.Moreover,apoA1 suppresses the PlGF expression,which selectively associated with pathological angiogenesis.

Fanlian Huazhuo Formula alleviates high-fat diet-induced nonalcoholic fatty liver disease by modulating autophagy and lipid synthesis signaling pathway

BACKGROUND Fanlian Huazhuo Formula(FLHZF)has the functions of invigorating spleen and resolving phlegm,clearing heat and purging turbidity.It has been identified to have therapeutic effects on type 2 diabetes mellitus(T2DM)in clinical application.Non-alcoholic fatty liver disease(NAFLD)is frequently diagnosed in patients with T2DM.However,the therapeutic potential of FLHZF on NAFLD and the underlying mechanisms need further investigation.AIM To elucidate the effects of FLHZF on NAFLD and explore the underlying hepatoprotective mechanisms in vivo and in vitro.METHODS HepG2 cells were treated with free fatty acid for 24 hours to induce lipid accumulation cell model.Subsequently,experiments were conducted with the different concentrations of freeze-dried powder of FLHZF for 24 hours.C57BL/6 mice were fed a high-fat diet for 8-week to establish a mouse model of NAFLD,and then treated with the different concentrations of FLHZF for 10 weeks.RESULTS FLHZF had therapeutic potential against lipid accumulation and abnormal changes in biochemical indicators in vivo and in vitro.Further experiments verified that FLHZF alleviated abnormal lipid metabolism might by reducing oxidative stress,regulating the AMPKα/SREBP-1C signaling pathway,activating autophagy,and inhibiting hepatocyte apoptosis.CONCLUSION FLHZF alleviates abnormal lipid metabolism in NAFLD models by regulating reactive oxygen species,autophagy,apoptosis,and lipid synthesis signaling pathways,indicating its potential for clinical application in NAFLD.

Inhibition of the immunoproteasome LMP_(2) ameliorates ischemia/hypoxia-induced blood–brain barrier injury through the Wnt/β-catenin signalling pathway

Background:Disruption of the blood–brain barrier(BBB)after a stroke can lead to brain injury and neurological impairment.Previous work confirmed the involvement of the immunoproteasome subunit of low molecular mass peptide 2(LMP2)in the pathophysiology of ischemia stroke.However,the relationship between the immunoproteasome LMP2 and the BBB remains unclear.Methods:Adult male Sprague–Dawley rats were subjected to transient middle cerebral artery occlusion/reperfusion(MCAO/R).Three days before MCAO,the rats were treated with lentivirus-mediated LMP2 shRNA preparations by stereotactical injection into the ipsilateral hemispheric region.The rat brain microvascular endothelial cell(RBMVEC)line was exposed to oxygen–glucose deprivation/reperfusion(OGD/R)to mimic ischemic conditions in vitro.The RNA interference-mediated knockdown of LMP2 orβ-catenin was analysed in vivo and in vitro.Analysis of the quantity of extravasated Evans blue(EB)and cerebral fluorescent angiography were performed to evaluate the integrity of the BBB.Immunofluorescence and Western blotting were employed to detect the expression of target proteins.Cell migration was evaluated using a scratch migration assay.The results of immunofluorescence,Western blotting and cell migration were quantified using the software ImageJ(Version 1.53).Parametric data from different groups were compared using one-way ANOVA followed by the least significant difference(LSD)test.Results:Cerebral ischemia led to lower levels of structural components of the BBB such as tight junction proteins[occludin,claudin-1 and zonula occludens(ZO-1)]in the MCAO/R group compared with the sham group(P<0.001).However,inhibition of the immunoproteasome LMP2 restored the expression of these proteins,resulting in higher levels of occludin,claudin-1 and ZO-1 in the LMP2-shRNA group compared with the control-shRNA group(P<0.001).In addition,inhibition of the immunoproteasome LMP2 contributed to higher microvascular density and decreased BBB permeability[e.g.,the quantity of extravasated EB:LMP2-shRNA group(58.54±7.37)μg/g vs.control-shRNA group(103.74±4.32)μg/g,P<0.001],and promoted the upregulation of Wnt-3a andβ-catenin proteins in rats following MCAO/R.In vitro experiments,OGD/R induced marked upregulation of LMP2,proapoptotic protein Bax and cleaved caspase-3,and downregulation of occludin,claudin-1,ZO-1 and Bcl-2,as well as inhibition of the Wnt/β-catenin pathway Wnt-3a andβ-catenin proteins in RBMVECs,compared with the control group under normal culture conditions(P<0.001).However,silencing of LMP2 gene expression reversed these protein changes and promoted proliferation and migration of RBMVECs following OGD/R.Silencing ofβ-catenin by transfection of RBMVECs withβ-catenin-si RNA aggravated the downregulation of tight junction proteins,and reduced the proliferation and migration of RBMVECs following OGD/R,compared with the control-siRNA group(P<0.001).LMP2-si RNA andβ-catenin-si RNA co-transfection partly counteracted the beneficial effects of silencing LMP2-siRNA on the levels of tight junction proteins in RBMVECs exposed to OGD/R.Conclusions:This study suggests that inhibition of the immunoproteasome LMP2 ameliorates ischemia/hypoxia induced BBB injury,and that the molecular mechanism involves the immunoproteasome-regulated activation of the Wnt/β-catenin signalling pathway under ischemic conditions.

Unveiling the role of hypoxia-inducible factor 2alpha in osteoporosis:Implications for bone health

BACKGROUND Osteoporosis(OP)has become a major public health problem worldwide.Most OP treatments are based on the inhibition of bone resorption,and it is necessary to identify additional treatments aimed at enhancing osteogenesis.In the bone marrow(BM)niche,bone mesenchymal stem cells(BMSCs)are exposed to a hypoxic environment.Recently,a few studies have demonstrated that hypoxiainducible factor 2alpha(HIF-2α)is involved in BMSC osteogenic differentiation,but the molecular mechanism involved has not been determined.AIM To investigate the effect of HIF-2αon the osteogenic and adipogenic differentiation of BMSCs and the hematopoietic function of hematopoietic stem cells(HSCs)in the BM niche on the progression of OP.METHODS Mice with BMSC-specific HIF-2αknockout(Prx1-Cre;Hif-2αfl/fl mice)were used for in vivo experiments.Bone quantification was performed on mice of two genotypes with three interventions:Bilateral ovariectomy,semilethal irradiation,and dexamethasone treatment.Moreover,the hematopoietic function of HSCs in the BM niche was compared between the two mouse genotypes.In vitro,the HIF-2αagonist roxadustat and the HIF-2αinhibitor PT2399 were used to investigate the function of HIF-2αin BMSC osteogenic and adipogenic differentiation.Finally,we investigated the effect of HIF-2αon BMSCs via treatment with the mechanistic target of rapamycin(mTOR)agonist MHY1485 and the mTOR inhibitor rapamycin.RESULTS The quantitative index determined by microcomputed tomography indicated that the femoral bone density of Prx1-Cre;Hif-2αfl/fl mice was lower than that of Hif-2αfl/fl mice under the three intervention conditions.In vitro,Hif-2αfl/fl mouse BMSCs were cultured and treated with the HIF-2αagonist roxadustat,and after 7 d of BMSC adipogenic differentiation,the oil red O staining intensity and mRNA expression levels of adipogenesis-related genes in BMSCs treated with roxadustat were decreased;in addition,after 14 d of osteogenic differentiation,BMSCs treated with roxadustat exhibited increased expression of osteogenesis-related genes.The opposite effects were shown for mouse BMSCs treated with the HIF-2αinhibitor PT2399.The mTOR inhibitor rapamycin was used to confirm that HIF-2αregulated BMSC osteogenic and adipogenic differentiation by inhibiting the mTOR pathway.Consequently,there was no significant difference in the hematopoietic function of HSCs between Prx1-Cre;Hif-2αfl/fl and Hif-2αfl/fl mice.CONCLUSION Our study showed that inhibition of HIF-2αdecreases bone mass by inhibiting the osteogenic differentiation and increasing the adipogenic differentiation of BMSCs through inhibition of mTOR signaling in the BM niche.

Endogenous Endothelin-1 Regulates Hypoxia-Induced Atrial Natriuretic Peptide Secretion by Activating the MAPK/ERK and PI3K/Akt Signaling Pathways in Isolated Beating Rabbit Atria

The present study investigated a possible mechanism for endogenous endothelin-1 (ET-1) regulation of atrial natriuretic peptide (ANP) secretion in isolated perfused acute hypoxic rabbit atria. Acute hypoxia significantly enhanced the release of ET-1 and the expression of the ET receptor (ETR) type A and B (ETRA and ETRB) in atrial tissues, with a concomitant increase in ANP secretion. The ETRA or ETRB antagonist, BQ123 (0.3 μmol/L) or BQ788 (0.3 μmol/L), respectively attenuated hypoxia-induced ANP secretion. Both antagonists significantly attenuated the levels of hypoxiainduced atrial phosphorylated (p)-extracellular signal-regulated kinase (ERK) and p-protein kinase B (Akt). The ERK and Akt inhibitors, PD098059 (30 μmol/L) and LY294002 (30 μmol/L), respectively mimicked the effect of the ETR antagonists. These results demonstrated that acute hypoxia- mediated atrial ET-1 regulated ANP secretion through ETR and the subsequent mitogenactivated protein kinase (MAPK)/ERK and ETR-phosphatidylinositol-3-kinase (PI3K)/Akt signaling pathways. These pathways may mediate atrial endocrine functions under hypoxic conditions.

Masseter Vestibular evoked myogenic potentials: A new tool to assess the vestibulomasseteric reflex pathway

Purpose: This review article provides the readers with an in-depth insight in understanding and interpreting various research literatures on the masseter vestibular evoked myogenic potentials(mVEMP). The article also reviews the contemporary researches involving the clinical applications of the mVEMP. Conclusions: Masseter VEMP is an evolving yet clinically promising neuro-otology test tool that has recently gained more research interest and is considered an additional tool to diagnose various vestibular disorders. Masseter VEMP assesses the functional integrity of the acoustic-masseteric and vestibulo-masseteric reflex pathways. The mVEMP could be used as a complementary test to evaluate the same peripheral generator as the cervical VEMP but a different central pathway i.e., vestibulo-trigeminal pathway. Various research studies that have experimented on parameters such as the effect of different electrode montages(zygomatic vs mandibular configurations), stimulation rates, filter settings and stimuli used to evoke mVEMP have been discussed in this article that could assist in the optimization of a comprehensive clinical protocol. The latency and the amplitude of mVEMP waveforms serve as significant parameters in differentiating normals from those of the clinical populations. Along with the cVEMPs and oVEMPs, mVEMP might help diagnose brainstem lesions in REM Sleep behaviour disorders, Multiple Sclerosis and Parkinson's disease. However, further studies are required to probe in this area of research.