Changes of Macular Microcirculation After Near Work in Myopic Patients / 中山大学学报(医学科学版)

ObjectiveTo compare the changes of retinal microcirculation indexes in the anterior and posterior macular areas of the eyes used at close range and to explore the possible causes of myopia affected by near work. MethodsWatching mobile phone video for 1 hour at close range was used as the method of defining near work. The OCTA technology was used to measure the superficial retinal microcirculation indexes within 6 by 6 mm macular area before and after near work， including the superficial retinal VLD from the nerve fiber layer to the inner boundary of the outer plexiform layer， the VPD， nonperfusion area of FAZ， FAZ-P and FAZ circulation，. The FAZ was divided int center， inner layer， outer layer and overall according to the region， and 11 microcirculation indexes were obtained to compare the differences between before and after near work. ResultsThe indexes of superficial retinal microcirculation in the macular area generally decreased after near work， except for FAZ-A and FAZ-P（P = 0.148， 0.975）. The largest differences among both VLD and VPD occurred between the central and inner layer（Difference = 1.00， 0.80， 0.02， 0.02，P = 0.001， 0.008， 0.001， 0.008）. No differences in microcirculation indexs were observed in the macular area after near work with different diopters and axial lengths. ConclusionNear work may affect the occurrence and development of myopia by affecting the changes of retinal microcirculation in the superficial layer of macula， leading to ischemia and hypoxia.

Betulin Targets Lipin1/2-Meidated P2X7 Receptor as a Therapeutic Approach to Attenuate Lipid Accumulation and Metaflammation

The present study focused on the potential mechanism of betulin (BT), a pentacyclic triterpenoid isolated from the bark of white birch (Betula pubescens), against chronic alcohol-induced lipid accumulation and metaflammation. AML-12 and RAW 264.7 cells were administered ethanol (EtOH), lipopolysaccharide (LPS) or BT. Male C57BL/6 mice were fed Lieber-DeCarli liquid diets containing 5% EtOH for 4 weeks, followed by single EtOH gavage on the last day and simultaneous treatment with BT (20 or 50 mg/ kg) by oral gavage once per day. In vitro, MTT showed that 0-25 mM EtOH and 0-25 μM BT had no toxic effect on AML-12 cells. BT could regulate sterolregulatory-element-binding protein 1 (SREBP1), lipin1/2, P2X7 receptor (P2X7r) and NOD-like receptor family, pyrin domains-containing protein 3 (NLRP3) expressions again EtOH-stimulation. Oil Red O staining also indicated that BT significantly reduced lipid accumulation in EtOH-stimulated AML-12 cells. Lipin1/2 deficiency indicated that BT might mediate lipin1/2 to regulate SREBP1 and P2X7r expression and further alleviate lipid accumulation and inflammation. In vivo, BT significantly alleviated histopathological changes, reduced serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and triglyceride (TG) levels, and regulated lipin1/2, SREBP1, peroxisome proliferator activated receptor α/γ (PPARα/γ) and PGC-1α expression compared with the EtOH group. BT reduced the secretion of inflammatory factors and blocked the P2X7rNLRP3 signaling pathway. Collectively, BT attenuated lipid accumulation and metaflammation by regulating the lipin1/2-mediated P2X7r signaling pathway.

Gentiopicroside Ameliorates the Progression from Hepatic Steatosis to Fibrosis Induced by Chronic Alcohol Intake

In current study, we aimed to investigate whether the gentiopicroside (GPS) derived from Gentiana manshurica Kitagawa could block the progression of alcoholic hepatic steatosis to fibrosis induced by chronic ethanol intake. C57BL/6 mice were fed an ethanol- containing Lieber-DeCarli diet for 4 weeks. LX-2 human hepatic stellate cells were treated with GPS 1 h prior to transforming growth factor-β (TGF-β) stimulation, and murine hepatocyte AML12 cells were pretreated by GPS 1 h prior to ethanol treatment. GPS inhibited the expression of type I collagen (collagen I), α-smooth muscle actin (α-SMA) and tissue inhibitor of metal protease 1 in ethanol-fed mouse livers with mild fibrosis. In addition, the imbalanced lipid metabolism induced by chronic ethanol-feeding was ameliorated by GPS pretreatment, characterized by the modulation of lipid accumulation. Consistently, GPS inhibited the expression of collagen I and α-SMA in LX-2 cells stimulated by TGF-β. Inhibition of lipid synthesis and promotion of oxidation by GPS were also confirmed in ethanol-treated AML12 cells. GPS could prevent hepatic steatosis advancing to the inception of a mild fibrosis caused by chronic alcohol exposure, suggesting GPS might be a promising therapy for targeting the early stage of alcoholic liver disease.

Dihydroquercetin ameliorates alcoholic liver steatosis through P2x7R-NLRP3 inflammasome pathway / 中国药理学与毒理学杂志

OBJECTIVE Dihydroquercetin(TAX)is the most abundant dihydroflavone found in on-ions,milk thistle and Douglas fir bark.We investigated whether TAX could inhibit the lipid accumulation in alcoholic liver steatosis in vivo and in vitro.METHODS An in vivo model was established by intragas-trically treating mice with ethanol,and an in vitro model was created by treating HepG2 cells with etha-nol.RESULTS TAX regulated Sterol Regulatory Element-binding Protein-1(SREBP1)and Acetyl CoA Carboxylase (ACC) expression via elevating Liver Kinase B1 (LKB1)/ AMP-activated Kinase (AMPK) phosphorylation. Also, TAX upregulated SIRT1 expression, which suppressed by ethanal intake. Suppression of Purinergic 2X7 receptor (P2x7R), nucleotide-binding oligomerization domain-like re-ceptor protein 3(NLRP3)and Cysteine protease-1(caspase-1)cleavage by TAX resulted in the inhibi-tion of Interleukin-1β(IL-1β) production and release. Additionally, TAX reduced lipogenesis and pro-moted lipid oxidation via the regulation of AMPK and ACC in ethanol-treated steatotic HepG2 cell.TAX downregulated IL-1β cleavage response to Lipopolysaccharides (LPS) plus adenosine triphosphate(ATP) stimulation in HepG2 cells. P2x7R deficiency attenuated lipid accumulation with increasing AMPK activity and decreasing SREBP1 expression in ethanol-treated HepG2 cells.CONCLUSION Our data showed that TAX exhibited the inhibitory properties on lipogenesis and hepatoprotective ca-pacity,indicating that TAX has therapeutic potential for preventing alcoholic liver steatosis.

Toll-like receptor 4-related regulation of Ornithogalum caudatum extract on inflammatory responses in LPS activated macrophages / 中国药理学与毒理学杂志

OBJECTIVE To investigate toll-like receptor 4(TLR4)-related the regulation of Ornithog-alum caudatum extract(OCE)on inflammatory responses in lipopolysaccharide(LPS)activated macro-phages.METHODS Primary peritoneal macrophage,Raw 264.7,and THP-1 were incubated in 96-well plate for 24 h and treated with OCE of the concentration of 0-400 μg/ml for 4h.The viability of cells was measured by MTT assay.Specific concentrations of OCE were added into the medium of primary peri-toneal macrophage, Raw 264.7, and THP-1, respectively, then following with lipopolysaccharides (LPS). Cells were harvested and the total cellular protein and nuclear protein were extracted, and the protein content was determined using BCA protein assay Kit.The expressions of TLR4,inducible nitric oxide synthase(iNOS),cyclooxygenase 2(COX-2),α-inhibitor of NF-κB(IκB-α)and nuclear factor-κB (NF-κB)were assayed by Western blot.The expressions of interleukin-1α(IL-1α),interleukin-1β(IL-1β), interleukin-18(IL-18),and tumor necrosis factor-α(TNF-α)were measured by RT-PCR.RESULTS The results of MTT showed that OCE has no cytotoxicity in Raw 264.7 cells between 1.56 μg/ml and 400 μg/ml. Compared with normal group,the expressions of TLR4,iNOS,COX-2,NF-κB and IL-1α,IL-1β,IL-18, TNF-α,the level of nitric oxide(NO)were significantly increased by LPS stimulation,while OCE pretreat-ment reduced these increase induced by LPS. However, OCE pretreatment reversed the reduction of IκB-α after LPS stimulation.CONCLUSION OCE might suppress TLR4 expression and block the inflamma-tion process of NF-κB and iNOS,further decrease the expression of COX-2 and inhibit the release of inflammatory factors.

Pleurotus citrinopileatus alleviates alcohol-induced fatty liver via upregulating AMPK signaling / 中国药理学与毒理学杂志

OBJECTIVE The current study was designed to investigate the anti-steatosis effect of Pleurotus citrinopileatus extract (PC) and the underlying mechanism in vivo and in vitro. METHODS Acute and chronic alcoholic hepatosteatosis murine models and ethanol-treated HepG2 cells were applied. RESULTS In vitro,the anti-steatosis effect of PC was further confirmed via Nile red staining in HepG2 cells treated with ethanol.Both of acute and chronic alcohol-induced mice hepatosteatosis model,PC decreased serum aminotransferase and triglyceride accumulation. Upregulated sterol-regulatory element binding protein1(Srebp1),purinergic ligand-gated ion channel 7receptor(P2X7R)and downregulated sirtuin1 (SIRT1), adenosine 5′-monophosphate (AMP)-activated protein kinase α (AMPKα) caused by acute and chronic alcohol intake were modulated by PC.In ethanol-exposed HepG2 cells,PC reduced lipid accumulation in a concentration-dependent manner and exhibited superior ability in controlling lipid accumulation compared with metformin. CONCLUSION PC could abolish hepatic lipid accumulation through regulating SIRT1-AMPKα signaling in acute and chronic alcohol-induced hepatic steatosis.

Gentiopicroside ameliorates LKB1/AMPK-dependent alcoholic hepatosteatosis via P2x7R-NLRP3 inflammasome / 中国药理学与毒理学杂志

OBJECTIVE Regulating P2x7R- NLRP3 inflammasome activation might be a potentialtherapeutic strategy to treat alcoholic hepatosteatosis. We investigated whether this process would be modulated by gentiopicroside (GPS), which is attributed to the bitterness of gentian root extract. METHODSAn in vivo model was established by intragastrically treating mice with ethanol, and an in vitro modelwas created by treating HepG2 cells with ethanol or treating RAW 264.7 macrophages and murinebone marrow- derived macrophages (BMDMs) with lipopolysaccharides (LPS) plus adenosine triphos-phate (ATP). RESULTS In alcoholic hepatosteatotic mice model, GPS decreased serum aminotrans-ferase and triglyceride accumulation. GPS regulated sterol regulatory element-binding protein-1 (Srebp1),peroxisome proliferators- actived receptors α (PPARα) and acetyl CoA carboxylase (ACC) expressionvia elevating liver kinase B1 (LKB1)/AMP-activated Kinase (AMPK). Suppression of nucleotide-bindingoligomerization domain-like receptor protein 3 (NLRP3), caspase-1 and expression by GPS resulted inthe inhibition of interleukin-1β (IL-1β) production. In ethanol-exposed HepG2 cells, GPS reduced lipo-genesis and promoted lipid oxidation via P2x7R- NLRP3 inflammasome activation. P2x7R silencingenhanced AMPK activity, and reduced Srebp1 expression in ethanol-treated hepatocytes. GPS down-regulated P2x7R-mediated inflammatory response to extracellular ATP in LPS-primed RAW 264.7 macro-phages and BMDMs. Additionally, P2x7R deficiency attenuated IL- 1β cleavage in RAW 264.7 macro-phages, and GPS further suppressed IL-1β cleavage. CONCLUSION Activation of LKB1/AMPK signalingby GPS might be mediated by P2x7R-NLRP3 inflammasome, suggesting a therapeutic utility of P2x7Rblockade in alcoholic hepatosteatosis treatment.