Paeoniflorin promotes PPARγ expression to suppress HSCs activation by inhibiting EZH2-mediated histone H3K27 trimethylation

BACKGROUND

The alleviating effect of paeoniflorin (Pae) on liver fibrosis has been established; however, the molecular mechanism and specific target(s) underlying this effect remain elusive.

PURPOSE

This study was to investigate the molecular mechanism underlying the regulatory effect of Pae on hepatic stellate cells (HSCs) activation in liver fibrosis, with a specific focus on the role of Pae in modulating histone methylation modifications.

METHODS

The therapeutic effect of Pae was evaluated by establishing in vivo and in vitro models of carbon tetrachloride (CCl4)-induced mice and transforming growth factor β1 (TGF-β1)-induced LX-2 cells, respectively. Molecular docking, surface plasmon resonance (SPR), chromatin immunoprecipitation-quantitative real time PCR (ChIP-qPCR) and other molecular biological methods were used to clarify the molecular mechanism of Pae regulating HSCs activation.

RESULTS

Our study found that Pae inhibited HSCs activation and histone trimethylation modification in liver of CCl4-induced mice and LX-2 cells. We demonstrated that the inhibitory effect of Pae on the activation of HSCs was dependent on peroxisome proliferator-activated receptor γ (PPARγ) expression and enhancer of zeste homolog 2 (EZH2). Mechanistically, Pae directly binded to EZH2 to effectively suppress its enzymatic activity. This attenuation leaded to the suppression of histone H3K27 trimethylation in the PPARγ promoter region, which induced upregulation of PPARγ expression.

CONCLUSION

This investigative not only sheds new light on the precise targets that underlie the remission of hepatic fibrogenesis induced by Pae but also emphasizes the critical significance of EZH2-mediated H3K27 trimethylation in driving the pathogenesis of liver fibrosis.

Si-Ni-San inhibits hepatic Fasn expression and lipid accumulation in MAFLD mice through AMPK/p300/SREBP-1c axis

BACKGROUND

Soothing the liver and regulating qi is one of the core ideas of traditional Chinese medicine (TCM) in the treatment of fatty liver. Si-Ni-San (SNS) is a well-known herbal formula in TCM for liver soothing and qi regulation in fatty liver treatment. However, its efficacy lacks modern scientific evidence.

PURPOSE

This study was aimed to investigate the impact of SNS on metabolic associated fatty liver disease (MAFLD) in mice and explore the underlying molecular mechanisms, particularly its effects on lipid metabolism in hepatocytes.

METHODS

The therapeutic effect of SNS was evaluated using in vivo and in vitro models of high-fat/high-cholesterol (HFHC) diet-induced mice and palmitic acid (PA)-induced hepatocytes, respectively. Molecular biological techniques such as RNA-sequencing (RNA-seq), co-immunoprecipitation (co-IP), and western blotting were employed to elucidate the molecular mechanism of SNS in regulating lipid metabolism in hepatocytes.

RESULTS

Our findings revealed that SNS effectively reduced lipid accumulation in the livers of HFHC diet-induced mice and PA-induced hepatocytes. RNA-seq analysis demonstrated that SNS significantly down-regulated the expression of fatty acid synthase (Fasn) in the livers of HFHC-fed mice. Mechanistically, SNS inhibited Fasn expression and lipid accumulation by activating adenosine monophosphate (AMP)-activated protein kinase (AMPK). Activation of AMPK suppressed the activity of the transcriptional coactivator p300 and modulated the protein stability of sterol regulatory element-binding protein-1c (SREBP-1c). Importantly, p300 was required for the inhibition of Fasn expression and lipid accumulation by SNS. Furthermore, SNS activated AMPK by decreasing adenosine triphosphate (ATP) production in hepatocytes.

CONCLUSION

This study provided novel evidence on the regulatory mechanisms underlying the effects of SNS on Fasn expression. Our findings demonstrate, for the first time, that SNS exerts suppressive effects on Fasn expression through modulation of the AMPK/p300/SREBP-1c axis. Consequently, this regulatory pathway mitigates excessive lipid accumulation and ameliorates MAFLD in mice.

Essential oil extracted from Quzhou Aurantii Fructus prevents acute liver failure through inhibiting lipopolysaccharide-mediated inflammatory response

Quzhou Aurantii Fructus (QAF) has a long history as a folk medicine and food for the treatment of liver diseases. While our earlier study provided evidence of hepatoprotective properties contained within the flavonoids and limonins constituents in QAF, the potential preventative effects afforded by essential oil components present within QAF remains enigmatic. In this study, we prepared Quzhou Aurantii Fructus essential oil (QAFEO) and confirmed its anti-inflammatory effects on liver inflammation through experimentation on lipopolysaccharide and D-galactosamine (LPS/D-GalN) induced acute liver failure (ALF) mouse models. Using RNA-sequence (RNA-seq) analysis, we found that QAFEO prevented ALF by systematically blunting the pathways involved in response to LPS and toll-like receptor signaling pathways. QAFEO effectively suppressed the phosphorylation of tank-binding kinase 1 (TBK1), TGF-beta activated kinase 1 (TAK1), interferon regulatory factor 3 (IRF3), and the activation of mitogen activated kinase-like protein (MAPK) and nuclear factor-kappa B (NF-κB) pathways in vivo and in vitro. Importantly, QAFEO substantially reduced myeloid differentiation primary response gene 88 (MyD88)- toll-like receptor 4 (TLR4) interaction levels. Moreover, 8 compounds from QAFEO could directly bind to REAL, TAK1, MyD88, TBK1, and IRF3. Taken together, the results of our study support the notion that QAFEO exerts a hepatoprotective effect through inhibiting LPS-mediated inflammatory response.

Saikosaponin A triggers cell ferroptosis in hepatocellular carcinoma by inducing endoplasmic reticulum stress-stimulated ATF3 expression

Ferroptosis is a type of nonapoptotic necrotic cell death characterized by iron-dependent lipid peroxidation. Saikosaponin A (SsA), a natural bioactive triterpenoid saponin extracted from Radix Bupleuri, has shown potent antitumor activity against various tumors. However, the underlying mechanism of the antitumor activity of SsA remains unclear. Here, we discovered that SsA induced HCC cell ferroptosis in vitro and in vivo. Using RNA-sequence analysis, we found that SsA mainly affected the glutathione metabolic pathway and inhibited the expression of cystine transporter solute carrier family 7 member 11 (SLC7A11). Indeed, SsA increased intracellular malondialdehyde (MDA) and iron accumulation, while it decreased the levels of reduced glutathione (GSH) in HCC. Deferoxamine (DFO), ferrostatin-1 (Fer-1) and GSH could rescue SsA-induced cell death, whereas Z-VAD-FMK was found ineffective in inhibiting SsA-induced cell death in HCC. Importantly, our result indicated that SsA induced the expression of activation transcription factor 3 (ATF3). SsA-induced cell ferroptosis and suppression of SLC7A11 are dependent on ATF3 in HCC. Moreover, we revealed that SsA induced ATF3 upregulation via activation of endoplasmic reticulum (ER) stress. Taken together, our findings support that ATF3-dependent cell ferroptosis mediated the antitumor effects of SsA, opening the possibility to explore SsA as a ferroptosis inducer in HCC.

Analysis of retinal arteriolar and venular parameters in primary open angle glaucoma

AIM

To measure the retinal vessels of primary open angle glaucoma (POAG) patients on spectral domain optical coherence tomography (SD-OCT) with a full-width at half-maximum (FWHM) algorithm to better explore their structural changes in the pathogenesis of POAG.

METHODS

In this retrospective case-control study, the right eyes of 32 patients with POAG and 30 healthy individuals were routinely selected. Images of the supratemporal and infratemporal retinal vessels in the B zones were obtained by SD-OCT, and the edges of the vessels were identified by the FWHM method. The internal and external diameters, wall thickness (WT), wall cross-sectional area (WCSA) and wall-to-lumen ratio (WLR) of the blood vessels were studied.

RESULTS

Compared with the healthy control group, the POAG group showed a significantly reduced retinal arteriolar outer diameter (RAOD), retinal arteriolar lumen diameter (RALD) and WSCA in the supratemporal (124.22±12.42 vs 138.32±10.73 µm, 96.09±11.09 vs 108.53±9.89 µm, and 4762.02±913.51 vs 5785.75±1148.28 µm², respectively, all P<0.05) and infratemporal regions (125.01±15.55 vs 141.57±10.77 µm, 96.27±13.29 vs 110.83±10.99 µm, and 4925.56±1302.88 vs 6087.78±1061.55 µm², all P<0.05). The arteriolar WT and WLR were not significantly different between the POAG and control groups, nor were the retinal venular outer diameter (RVOD), retinal venular lumen diameter (RVLD) or venular WT in the supratemporal or infratemporal region. There was a positive correlation between the arteriolar parameters and visual function.

CONCLUSION

In POAG, narrowing of the supratemporal and infratemporal arterioles and a significant reduction in the WSCA is observed, while the arteriolar WT and WLR do not change. Among the venular parameters, the external diameter, internal diameter, WT, WLR, and WSCA of the venules are not affected.

Iatrogenic retinal breaks and postoperative retinal detachments in microincision vitrectomy surgery compared with conventional 20-gauge vitrectomy: a meta-analysis

PURPOSE

To assess the incidence of iatrogenic retinal breaks (IRBs) and postoperative retinal detachments (RDs) in microincision vitrectomy surgery (MIVS) compared with 20-gauge (20 G) vitrectomy.

METHODS

A comprehensive literature search was performed to find relevant studies and a meta-analysis of the IRBs and postoperative RDs rates after 20 G vitrectomy versus MIVS was conducted.

RESULTS

Thirty-two studies were selected, including 14,373 eyes (6932 eyes in the 20 G group, 7441 eyes in the MIVS group). The meta-analysis demonstrated that the incidence of IRBs was significantly higher in 20 G vitrectomy vs. MIVS (OR = 2.22, 95% CI, 1.93-2.57, P < 0.00001) and in a subanalysis vs. 23 G MIVS (OR = 2.19, 95% CI, 1.87-2.56, P < 0.00001) and vs. 25 G MIVS (OR = 2.27, 95% CI, 1.62-3.18, P < 0.00001). Similar result was obtained in a subanalysis for macular surgery (OR = 2.44, 95% CI, 1.99-2.99, P < 0.00001), and also for sclerotomy-related IRBs (OR = 3.73, 95% CI, 2.55-5.44, P < 0.00001), but not for surgically induced posterior vitreous detachment-related IRBs (OR = 1.59, 95% CI, 0.89-2.84, P = 0.12). The incidence of postoperative RDs in 20 G vitrectomy was significantly higher compared to MIVS (OR = 1.72, 95% CI, 1.21-2.46, P = 0.003) and in a subanalysis vs. 23 G MIVS (OR = 2.45, 95% CI, 1.50-4.00, P = 0.0003), but not for 25 G MIVS (OR = 1.01, 95% CI, 0.63-1.64, P = 0.96). Similar result was obtained in a subanalysis for macular surgery (OR = 1.89, 95% CI, 1.26-2.85, P = 0.002).

CONCLUSION

This meta-analysis demonstrated that MIVS is associated with a lower risk of IRBs and postoperative RDs compared to 20 G vitrectomy.

Airway Foreign Body: A Difficult and Often Neglected Diagnosis in Asthmatic Child in Emergency Department

Foreign body inhalation is not uncommonly encountered in children. Diagnosis could be difficult if parent cannot recall any relevant clinical history. This is especially true for an asthmatic child as respiratory signs and symptoms are believed by most emergency physicians to be attributed to asthma alone. We present a case of inhalation of peanut to the left main bronchus in an asthmatic child who was initially misdiagnosed as exacerbation of bronchial asthma. Meticulous clinical history and careful physical examination supplemented by chest radiograph in full expiration would raise the clinical suspicion of an obstructing foreign body within the bronchial tree. The diagnosis was subsequently confirmed on bronchoscopy and the obstructing peanut was successfully removed. As emergency physicians, we cannot attribute respiratory symptoms in an asthmatic child to be due to asthma alone. In the presence of respiratory symptoms of acute onset, unilateral physical signs and radiological evidence of air-trapping, foreign body inhalation should be considered even in the absence of accurate clinical history. Prompt arrangement for bronchoscopy assessment is recommended.

[Overexpression of Keap1 inhibits the cell proliferation and metastasis and overcomes the drug resistance in human lung cancer A549 cells]

OBJECTIVE

To investigate the effect of Keap1-Nrf2 pathway on cell proliferation, metastasis and drug resistance of human lung cancer A549 cell line.

METHODS

A549-Keap1 cell line, constantly expressing wild type Keap1, was established by lentiviral transfection. Real-time RT-PCR and western blot were used to determine the expression of Nrf2 and its target gene in A549 cells. Sulforhodamine B (SRB) assay, flow cytometry, colony formation assay, transwell assay, and cell wound-healing assay were performed to explore the effect of wild type Keap1 expression on the proliferation, invasion, migration and drug resistance of A549 cells.

RESULTS

Over-expressed Keap1 decreased the expression of Nrf2 protein and the mRNA level of its downstream target genes and inhibited the ability of cell proliferation and clone formation of A549 cells. Keap1 overexpression induced G0/G1 phase arrest. The percentage of A549-Keap1 cells in G0/G1 phase was significantly higher than that of A549-GFP cells (80.2±5.9)% vs. (67.1±0.9%)(P<0.05). Compared with the invasive A549-Keap1 cells (156.33±17.37), the number of invasive A549-GFP cells was significantly higher (306.67±22.19) in a high power field. Keap1 overexpression significantly enhanced the sensitivity of A549 cells to carboplatin and gemcitabine (P<0.01). The IC50s of carboplatin in A549-Keap1 and A549-GFP cells were (52.1±3.3) μmol/L and (107.8±12.9) μmol/L, respectively. The IC50s of gemcitabine in A549-Keap1 and A549-GFP cells were (6.8±1.2) μmol/L and (9.9±0.5) μmol/L, respectively.

CONCLUSION

Keap1 overexpression significantly inhibits the expression of Nrf2 and its downstream target genes, suppresses tumor cell proliferation and metastasis, and enhances the sensitivity of A549 cells to anticancer drugs.

Overexpression of OsPGIP1 Enhances Rice Resistance to Sheath Blight

Rice sheath blight (SB), caused by necrotrophic pathogen Rhizoctonia solani, is one of the most destructive rice diseases, and no major resistance genes are available. Polygalacturonase-inhibiting proteins (PGIP) are extracellular leucine-rich repeat proteins and play important roles in plant defense against different pathogenic fungi by counteracting secreted fungal polygalacturonases (PG). However, the role of PGIP in conferring resistance to rice SB remains to be thoroughly investigated. Here, we showed that OsPGIP1 is capable of inhibiting PG derived from R. solani. Our real-time reverse-transcription polymerase chain reaction results indicated that resistant rice 'YSBR1' and 'Jasmine 85' express significantly higher levels of OsPGIP1 than susceptible 'Lemont'. Our results also show that OsPGIP1 is most highly expressed at the late tillering stage in the sheath of YSBR1, coinciding with the critical stage of SB development in field. More importantly, the OsPGIP1 level is highly elevated by inoculation with R. solani in resistant cultivars but not in susceptible Lemont. Overexpression of OsPGIP1 significantly increased rice resistance to SB and inhibited tissue degradation caused by R. solani-secreted PG. Furthermore, OsPGIP1 overexpression did not affect rice agronomic traits or yield components. Together, our results not only demonstrate the important role of OsPGIP1 in combatting the rice SB disease but also provide a new avenue to the improvement of rice SB resistance by manipulating an endogenous gene.

First Report of Pestalotiopsis sydowiana Causing Leaf Necrosis of Myrica rubra in China

Red bayberry (Myrica rubra Seib. & Zucc.) has great economic importance in eastern and southern China. However, increasing cultivation of red bayberry has resulted in an increase in diseases such as leaf necrosis. In April 2011, a survey was conducted to identify the causal agents of leaf necrosis of red bayberry (cv. Biqi) in Cixi City, Zhejiang Province. Symptoms began with oval and pale brown lesions (2 mm in diameter) that developed into a round to irregular shape (4 to 12 mm in diameter) with pale brown centers and dark brown borders. After approximately 4 months, necrotic lesions expanded to the leaf tips or margins. Black acervuli developed on lesions at later stages. Leaf tissues were surface sterilized with 0.5% sodium hypochlorite for 3 min and rinsed in sterile water before plating onto potato dextrose agar (PDA). Seven isolates were obtained from four samples from four fields on PDA at 25°C. The colonies were cottony white with filiform edges and produced a honey yellow color into the agar at 7 days. Conidia were produced in ink-like fruiting bodies at 4 days at 25°C on PDA. Conidia were straight or slightly curved, fusiform, and five celled with constrictions at the septa. Conidia ranged from 18.7 to 25.8 × 6.2 to 7.7 μm with hyaline apical and basal cells. Thirteen percent of the apical cells had two and the rest had three hyaline appendages ranging from 11.2 to 26.0 μm long. Basal appendages were hyaline, straight, and varied from 3.6 to 5.8 μm long. The color of three median cells was light to dark brown and demonstrated versicolorous. These morphological characteristics matched those of Pestalotiopsis sydowiana (Bresadola) Sutton (1). The morphological identification of the fungus was confirmed by nucleotide blast analysis of the 5.8S subunit and flanking internal transcribed spacers (ITS1 and ITS2) of rDNA regions (GenBank Accession No. JQ322999), which revealed 100% with those of other P. sydowiana isolates (e.g., GenBank Accession No. FJ478105). Koch's postulates were confirmed with 20 healthy leaves of the same size on three branches of three plants in the field. Leaves were wounded by pressing slightly with sterile needles. Mycelial plugs (5 mm in diameter) obtained from the periphery of 7-day-old cultures were placed onto the wounds and covered with sterile-water-saturated cotton. Wounded leaves treated with sterile agar plugs served as controls. The inoculated leaves were sealed in moist plastic bags for 24 h to establish high humid conditions at 21 to 30°C. After 23 days, symptoms on all inoculated leaves were identical to those described above, whereas noninoculated control leaves did not show any symptoms. The fungus was consistently reisolated from the lesions. To our knowledge, this is the first report of P. sydowiana causing leaf necrosis of M. rubra in China. Results can help to better understand the diseases threatening red bayberry trees and develop effective control strategies for better fruit production. Reference: (1) E. F. Guba. Monograph of Monochaetia and Pestalotia. Harvard University Press, Cambridge, MA, 1961.

Tanshinone II A attenuates inflammatory responses of rats with myocardial infarction by reducing MCP-1 expression

The root of Salvia miltiorrhiza Bunge, a well-known traditional Chinese medicine, has been used effectively for the treatment of cardiovascular diseases for a long time. The mechanisms underlying this therapeutic effect are not, however, fully understood. Tanshinone IIA (Tan IIA) is one of the major active components of this Chinese medicine. Therefore, the present study was performed to investigate whether Tan IIA, which has shown a cardio-protective capacity in myocardial ischemia, has an inhibitory effect on the inflammatory responses following myocardial infarction (MI) and its potential mechanisms. In an in vivo study, rat MI model was induced by permanent left anterior descending coronary artery (LAD) ligation. After the operation rats were divided into three groups (sham, MI and Tan IIA). Tan IIA was administered intragastrically at a dose of 60mg/kg body wt./day. One week later, rats were sacrificed and the hemodynamic, pathological and molecular biological indices were examined. In an in vitro study, the inflammatory model was established by TNF-alpha stimuli on cardiacmyocyte and cardiac fibroblasts. Tan IIA attenuates the MI pathological changes and improves heart function, and reduces expression of MCP-1, TGF-beta(1) and macrophage infiltration. Furthermore, Tan IIA could also decrease the expression of TNF-alpha and activation of nuclear transcription factor-kappa B (NF-kappaB). In vitro, Tan IIA could reduce MCP-1 and TGF-beta(1)secretion of cardiac fibroblasts. The present study demonstrated that the cardioprotective effects of Tan IIA might be attributed to its capacity for inhibiting inflammatory responses.

Preparation of ZnO colloids by aggregation of the nanocrystal subunits

Colloidal ZnO particles with narrow size distribution were prepared via a sol-gel process by base-catalyzed hydrolysis of zinc acetate. The morphology of ordered arrays of the particles was recorded by SEM. SEM also reveals that these uniform particles were composed of tiny ZnO subunits (singlets) sized of several nanometers. The size of the singlets, which is confirmed by X-ray diffraction and UV-vis absorption spectra, increases as the aging time is prolonged. The size-selective formation of colloids by aggregation of nanosized subunits is proposed to consist of two-stage growth by nucleation of nanosized crystalline primary particles and their subsequent aggregation into polycrystalline secondary colloids. The aggregates are all spherical because the internal rearrangement processes are fast enough. The ZnO colloids, i.e., the aggregates, tend to self-assemble into well-ordered hexagonal close-packed structures. Room-temperature photoluminescence was characterized for green and aged ZnO.

Unilateral vocal cord paralysis following endotracheal intubation--a case report

A 41-year-old man of ASA physical status class I was scheduled to receive the video-assisted thoracoscopic T2 sympathectomy for hyperhidrosis palmaris. The elective surgery was performed smoothly under general anesthesia with endotracheal intubation. However, the patient complained of hoarseness in the postoperative period. A stroboscopic examination showed that the left vocal cord remained stationary in the paramedian position, signifying left vocal cord paralysis. In the case, we believed it was most likely that endotracheal intubation might be responsible for the unilateral vocal cord paralysis. The possible cause was that during placement or thereafter during positioning, the endotracheal tube was malposed or slipped upward, rendering its inflated cuff to rest against the vocal cords. Another reason was that the cuff which was over inflated made the vocal cords under constant pressure. Both conditions may cause damage to the anterior branch of the recurrent laryngeal nerve. We also discussed the general management and prophylaxis for the unilateral vocal cord paralysis.

[Combined gu chi wan and spiramycin in the treatment of periodontal disease]

The purpose of the present study is to evaluate clinical effect of the integrated traditional Chinese and western medicine in the treatment of periodontal disease. 90 patients suffered from mild to advanced periodontitis were divided into two groups. The gu chi wan (tooth firming pills) group was administered tooth firming pills 4 mg twice daily for 3-6 months combined with spiramycin 0.2 four times daily for 5 days and routine periodontal treatment. The spiramycin group, as control, was administered spiramycin 0.2 four times daily for 5 days combined with routine periodontal treatment. The clinical parameters: GI, PLI, PDI and serial radiographs were checked on the beginning of study and through 3, 6, 12, 24 months follow up study. The results showed that the GI and PDI of the gu chi wan group decreased significantly than the control group (P less than 0.001). The inflammatory recurrence rate was 33% in the control group and 12% in gu chi wan group and the serial radiographs demonstrated that a higher incidence of bone fill occurred in gu chi wan group than in the control group (P less than 0.01).

Bacteriological study of juvenile periodontitis in China

The predominant cultivable bacteria associated with juvenile periodontitis (JP) in China were studied for the first time. Subgingival plaque samples were taken on paper points from 23 diseased sites in 15 JP patients and from 7 healthy sites in 7 control subjects. Serially diluted plaque samples were plated on nonselective blood agar and on MGB agar, a selective medium for the isolation of Actinobacillus actinomycetemcomitans. Fifteen or more isolated colonies from each sample (in sequence without selection) were purified for identification. The results indicated that the microflora in healthy sulci of the 7 control subjects was significantly different from that in diseased sites of JP patients. The predominant species in healthy sulci were Streptococcus spp. and Capnocytophaga gingivalis. In JP patients, Eubacterium sp. was found in significantly higher frequency and proportion. Actinobacillus actinomycetemcomitans was not detected in any samples. It appears that this species is not associated with juvenile periodontitis in China.