Role of Endoplasmic Reticulum Stress in Atherosclerosis and Its Regulation by Traditional Chinese Medicine： A Review / 中国实验方剂学杂志

Atherosclerosis （AS） is a chronic inflammatory pathological process in which lipid and/or fibrous substances are deposited in the intima of arteries， and it is one of the pathological bases of many cardiovascular and cerebrovascular diseases. Endoplasmic reticulum stress （ERS） is a protective mechanism of cell adaptation. Moderate ERS can reduce abnormal protein aggregation and increase the degradation of misfolded proteins to repair and stabilize the internal environment， while excessive ERS can cause unfolded protein reaction， activate inflammation， oxidative stress， apoptosis， autophagy， and other downstream pathways， and lead to cell damage， or even apoptosis. A large number of studies have shown that ERS mediates a variety of pathological processes related to AS， affects endothelial cells， smooth muscle cells， macrophages， endothelial progenitor cells， and other cell components closely related to its occurrence and development， influences the progress of AS by regulating cell function， and promotes the formation of AS plaque， the transformation of stable plaque to unstable plaque， and the rupture of unstable plaque. Regulation of ERS may be a key target for the prevention and treatment of AS， and it is a research hotspot at present. Traditional Chinese medicine （TCM） believes that the origin of AS is the imbalance of Yin and Yang， the disharmony of Zangfu organs， and the abnormal operation of Qi， blood， and body fluid， which leads to the accumulation of phlegm， blood stasis， and other pathological products in the pulse channels， making the blood flow blocked or misfunction and causing the disease， which belongs to the syndrome of deficiency in origin and excess in superficiality. As the pathogenesis of AS is complex， and the symptoms are diverse， TCM has significant advantages in treating AS because of its multiple targets， multiple pathways， stable efficacy， strong individualization， and high safety. This paper systematically elaborated on the role of ERS in the occurrence and development of AS and summarized the mechanism research on the regulation and control of ERS by Chinese herbal monomer， Chinese herbal extract， Chinese herbal compound， and proprietary medicine， so as to provide a theoretical basis for clinical research and drug development in the prevention and treatment of AS.

Effect of low concentration of sodium fluoride on osteogenic/odontogenic differentiation of human dental pulp cells / 口腔疾病防治

Objective@#To study the effect of low concentrations of sodium fluoride on the osteogenic/odontogenic differentiation of human dental pulp cells (hDPCs) in vitro.@*Methods@#This study was reviewed and approved by the Ethics Committee. hDPCs were cultured using a modified tissue explant technique in vitro. The effects of different concentrations of sodium fluoride on the proliferation of hDPCs were measured by methylthiazol tetrazolium (MTT) assay. Appropriate concentrations were added to the osteogenic/odontogenic differentiation induction medium, and the cells were induced in vitro. Alizarin red S staining was used to detect the osteoblastic/odontogenic differentiation ability of the cells, and the mRNA expression of the key differentiation factors was detected by RT-qPCR. Moreover, the expression of key molecules of endoplasmic reticulum stress (ERS) was detected by RT-qPCR and Western blot. The data were analyzed with the SPSS 18.0 software package.@*Results@#Low concentration of NaF (0.1 mmol/L) could stimulate cell proliferation in vitro, while a high concentration (5-10 mmol/L) could inhibit cell proliferation (P<0.05). According to the literature and the experimental data, 0.1 mmol/L NaF was selected as the following experimental concentration. The levels of alizarin red S staining were increased after NaF induction of mixed osteogenic/odontogenic differentiation in vitro. The mRNA expression levels of key molecules for osteogenic/odontogenic differentiation, dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP) and osteocalcin (OCN), were increased (P<0.05). The mRNA levels of ERS markers (splicing x-box binding protein-1 (sXBP1), glucose-regulated protein 78 (GRP78) and activating transcription Factor 4 (ATF4) were increased in NaF-treated cells. The protein expression levels of key ER stress molecules (phosphorylated RNA-activated protein kinase-like ER-resident kinase (p-PERK), phosphorylated eukaryotic initiation factor-2α (p-eIF2α) and ATF4) were higher in NaF-treated cells.@*Conclusion@#A low concentration of NaF promotes the osteogenic/odontogenic differentiation of hDPCs and increases the level of ER stress.

Mechanism of Yishen Tongluo Prescription in Inhibiting Endoplasmic Reticulum Stress and Improving Apoptosis of Renal Tubular Epithelial Cells Based on PERK/ATF4/CHOP / 中国实验方剂学杂志

ObjectiveTo investigate the effect of Yishen Tongluo prescription （YSTLP） on apoptosis of renal tubular epithelial cells and explore the mechanism based on endoplasmic reticulum stress pathway of protein kinase R-like endoplasmic reticulum kinase （PERK）/activating transcription factor 4 （ATF4）/transcription factor C/EBP homologous protein （CHOP）. MethodThe db/db mice were randomly divided into model group， valsartan group （10 mg·kg-1）， and low， middle， high-dose YSTLP groups （1， 2.5， 5 g·kg-1）. Samples were collected after eight weeks of drug intervention. In addition， db/m mice in the same litter served as the control group. Human renal tubular epithelial cells （HK-2） were cultured in vitro and divided into the control group， advanced glycated end-product （AGE） group， and AGE + low， middle， and high-dose YSTLP groups （100， 200， 400 mg·L-1）. TdT-mediated dUTP nick end labeling （TUNEL） staining was used to detect the apoptosis rate of HK-2 cells. Methylthiazolyldiphenyl-tetrazolium bromide （MTT） assay was conducted to detect the viability of HK-2 cells. Calcium fluorescence probe staining and luciferase reporter gene method were adopted to detect the luciferase activity of folded protein response element （UPRE） and endoplasmic reticulum stress. Immunohistochemical （IHC） analysis was carried out to measure the protein expressions of phosphorylated PKR （p-PERK）， CHOP， and ATF4. Real-time polymerase chain reaction （Real-time PCR） was used to measure the mRNA expression levels of CHOP and X-box binding protein 1 （XBP1） in mouse kidney and HK-2 cells. Western blot was used to detect the protein expression level of p-PERK， PERK， CHOP， ATF4， B-cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax）， and cleaved Caspase-3 in mouse kidney and HK-2 cells. ResultIn the cellular assay， HK-2 cell viability was significantly reduced， and the apoptosis rate was elevated in the AGE group compared with the control group （P<0.01）. The mRNA and protein expression levels of apoptosis-related factor Bcl-2 were significantly reduced （P<0.01）， and those of Bax were significantly increased （P<0.01）. The protein expression level of cleaved Caspase-3 was significantly increased （P<0.01）. Compared with the AGE group， YSTLP administration treatment resulted in elevated cell viability and reduced apoptosis rate （P<0.01）. The mRNA and protein expression levels of Bcl-2 were significantly elevated in a time- and dose-dependent manner （P<0.01）， and those of Bax were significantly reduced in a time- and dose-dependent manner. The protein expression level of cleaved Caspase-3 was significantly reduced in a time- and dose-dependent manner （P<0.01）. The intracellular Ca2+ imbalance and UPRE luciferase fluorescence intensity were increased in the AGE group compared with the control group （P<0.01）. The mRNA levels of endoplasmic reticulum stress-related factors CHOP and XBP1 were significantly increased （P<0.01）， and the protein expression levels of p-PERK， CHOP， and ATF4 were significantly increased （P<0.05）. Compared with the AGE group， YSTLP effectively improved intracellular Ca2+ imbalance in HK-2 cells and decreased UPRE luciferase fluorescence intensity in a dose-dependent manner （P<0.01）. It reduced the mRNA levels of endoplasmic reticulum stress-related factors CHOP and XBP1 （P<0.01） and the protein expression levels of intracellular p-PERK， CHOP， and ATF4 in a dose- and time-dependent manner （P<0.01）. In animal experiments， the protein expression level of Bcl-2 was significantly reduced（P<0.01）， and that of cleaved Caspase-3 and Bax was significantly increased in the model group compared with the control group （P<0.05）. The protein expression level of Bcl-2 was dose-dependently elevated， and that of cleaved Caspase-3 and Bax was dose-dependently decreased in the YSTLP groups compared with the model group （P<0.01）. Compared with the control group， the mRNA expression levels of CHOP and XBP1 were significantly elevated in the model group （P<0.05， P<0.01）， and the protein expression levels of p-PERK， CHOP， and ATF4 were significantly increased （P<0.05）. Compared with the model group， YSTLP significantly decreased the mRNA expression levels of CHOP and XBP1 （P<0.01） and the protein expression levels of p-PERK， CHOP， and ATF4 （P<0.01）. ConclusionYSTLP can effectively inhibit endoplasmic reticulum stress and improve apoptosis of renal tubular epithelial cells， and its mechanism may be related to the regulation of the PERK/AFT4/CHOP pathway.

High-intensity interval training (treadmill) effects in myokines and endoplasmic reticulum stress of calf muscles in obese mice / Efectos del entrenamiento interválico de alta intensidad (trotadora) en miocinas y estrés del retículo endoplasmático de los músculos surales en ratones obesos

SUMMARY: Obesity is commonly associated with chronic tissue inflammation and skeletal muscle dysfunction. The study aimed to investigate the effects of High-Intensity Interval training (HIIT) on myokines and endoplasmic reticulum (ER) stress of diet- induced obese (DIO) mice. Three-month-old C57BL/6 male mice were fed a control (C) diet (n=20) or a high-fat (HF) diet (n=20) for 16 weeks. Then, half of the groups underwent HIIT (treadmill running) for an additional four weeks. HIIT increased calf muscles' contribution to BW (+24 %) and reduced weight gain in HF/HIIT than in HF (-120 %). Intramuscular fat accumulation was observed in HF and HF/ HIIT. Peak velocity was higher in HF/HIIT compared to HF (+26 %). Plasma insulin did not change, but glycemia was lower in HF/HIIT than in HF (-30 %). Fndc5 (+418 %) and Irisin (+72 %) were higher in HF/HIIT than in HF. Muscle Fgf21 was higher in HF/HIIT compared to HF (+30 %). In addition, NfKb (-53 %) and Tnfa (-63 %) were lower in HF/HIIT than in HF. However, Il1b (-86 %), Il6 (- 48 %), Il7 (-76 %), and Il15 (-21 %) were lower in HF/HIIT than in HF. Finally, HIIT reduced ER stress in HF/HIIT compared to HF: Atf4, -61 %; Chop, -61 %; Gadd45, -95 %. In conclusion, HIIT leads to weight loss and avoids muscle depletion. HIIT improves blood glucose, Irisin-Fndc5, and peak velocity. In addition, HIIT mitigates muscle inflammation and ER stress.

La obesidad es asociada comúnmente con inflamación tisular crónica y disfunción del músculo esquelético. El estudio tuvo como objetivo investigar los efectos del entrenamiento de intervalos de alta intensidad (HIIT) en las mioquinas y el estrés del retículo endoplásmico (ER) de ratones obesos inducidos por dieta (DIO). Se alimentó a ratones macho C57BL/6 de tres meses de edad con una dieta control (C) (n=20) o una dieta rica en grasas (HF) (n=20) durante 16 semanas. Luego, la mitad de los grupos se sometieron a HIIT (carrera en una trotadora) durante cuatro semanas más. HIIT aumentó la contribución de los músculos de la pantorrilla al BW (+24 %) y redujo el aumento de peso en HF/HIIT en HF (-120 %). Se observó acumulación de grasa intramuscular en HF y HF/HIIT. La velocidad máxima fue mayor en HF/HIIT en comparación con HF (+26 %). La insulina plasmática no cambió, pero la glucemia fue menor en HF/HIIT que en HF (-30 %). Fndc5 (+418 %) e Irisin (+72 %) fueron mayores en HF/HIIT que en HF. El Fgf21 muscular fue mayor en HF/ HIIT en comparación con HF (+30 %). Además, NfKb (-53 %) y Tnfa (-63 %) fueron menores en HF/HIIT que en HF. Sin embar- go, Il1b (-86 %), Il6 (-48 %), Il7 (-76 %) e Il15 (-21 %) fueron más bajos en HF/HIIT que en HF. Finalmente, HIIT redujo el estrés de RE en HF/HIIT en comparación con HF: Atf4, -61 %; Picar, - 61 %; Gadd45, -95 %. En conclusión, HIIT conduce a la pérdida de peso y evita el agotamiento muscular. HIIT mejora la glucosa en sangre, Irisin-Fndc5 y la velocidad máxima. Además, HIIT mitiga la inflamación muscular y el estrés ER.

Regulación del calcio por SERC-A antes de la enfermedad de Alzheimer y durante la misma / Calcium regulation by SERC-A before and during Alzheimer disease

Hay muchos factores implicados en la incidencia de la enfermedad de Alzheimer que, en combinación, terminan por impedir o dificultar las funciones neuronales normales. Actualmente, poco se conoce sobre la regulación del calcio, antes de la enfermedad y durante la misma. La inestabilidad interna de los niveles de calcio se asocia a un mayor riesgo vascular, condición prevalente en un gran número de individuos ya comprometidos por la enfermedad de Alzheimer. Esta revisión proporciona una reevaluación de los mecanismos moleculares de la ATPasa dependiente de Ca2+ del retículo sarcoendoplásmico (SERC-A) en la enfermedad y analiza los aspectos más destacados de la función de los canales de calcio dependientes de voltaje; de esta manera, se podrán abrir nuevas alternativas de tratamiento. Estos mecanismos de regulación son clínicamente relevantes, ya que se ha implicado la función irregular de SERC-A en diversas alteraciones de la función cerebral.

There are many factors involved in the incidence of Alzheimer's disease that, in combination, impede or hinder normal neuronal functions. Little is currently known about calcium regulation before and during the disease. Internal instability of calcium levels is associated with increased vascular risk, a prevalent condition in a high number of individuals already compromised by Alzheimer's disease. This review provides a reevaluation of the molecular mechanism of the sarcoendoplasmic reticulum calcium ATPase (SERC-A) in the disease and discusses salient aspects of voltage-gated calcium channel function; in these way new alternatives could be open for its treatment. These regulation mechanisms are clinically relevant since the irregular functions of SERC+A has been implicated in pathologies of brain function.

A novel defined risk signature of endoplasmic reticulum stress-related genes for predicting the prognosis and immune infiltration status of ovarian cancer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Endoplasmic reticulum (ER) stress, as an emerging hallmark feature of cancer, has a considerable impact on cell proliferation, metastasis, invasion, and chemotherapy resistance. Ovarian cancer (OvCa) is one of the leading causes of cancer-related mortality across the world due to the late stage of disease at diagnosis. Studies have explored the influence of ER stress on OvCa in recent years, while the predictive role of ER stress-related genes in OvCa prognosis remains unexplored. Here, we enrolled 552 cases of ER stress-related genes involved in OvCa from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts for the screening of prognosis-related genes. The least absolute shrinkage and selection operator (LASSO) regression was applied to establish an ER stress-related risk signature based on the TCGA cohort. A seven-gene signature revealed a favorable predictive efficacy for the TCGA, International Cancer Genome Consortium (ICGC), and another GEO cohort (P<0.001, P<0.001, and P=0.04, respectively). Moreover, functional annotation indicated that this signature was enriched in cellular response and senescence, cytokines interaction, as well as multiple immune-associated terms. The immune infiltration profiles further delineated an immunologic unresponsive status in the high-risk group. In conclusion, ER stress-related genes are vital factors predicting the prognosis of OvCa, and possess great application potential in the clinic.

Research progress in the role of endoplasmic reticu-lum stress in cerebral ischemia-reperfusion injury / 中国药理学与毒理学杂志

During cerebral ischemia-reperfusion injury(CIRI),endoplasmic reticulum stress(ERS)leads to the development and progression of a series of deleterious physiological responses such as oxidative stress,dis-turbed calcium ion homeostasis,inflammation,apoptosis and autophagy.The unfolded protein response(UPR)is the main pathway activated by ERS,which regulates the expression of related factors within the endoplasmic reticu-lum(ER)and reduces protein translation levels.Prolonged and intense ERS may lead to cell death.Excessive ERS induces apoptosis mediated by C/EBP homologous pro-tein(CHOP),caspase-12 and c-Jun N-terminal kinase(JNK),thereby exacerbating brain damage.The thresh-old for the transition from adaptive mechanisms to apop-totic mechanisms during ERS depends on multiple fac-tors,including the cell status and environment,signaling pathway activity status,cumulative cascade,and the dose and time of ERS inducers.Further research is needed to completely elucidate the mechanism of ERS.Although the factors associated with the PERK and ATF6 path-ways are less extensively studied,their regulators still exist.Deficiency of protein tyrosine phosphatase 1B(PTP1B)leads to increased phosphorylation of PERK-eIF2α,while regulation of the proteasome and regulation of the XBP1 target gene WFS1 may also affect ATF6 sta-bility.In addition,differences in the structure,gene expres-sion,and metabolism of different types of neurons,as well as in their internal environment,may lead to differ-ences in their response to and impact on ERS.Differenc-es in UPR signaling pathways occur in hippocampal neurons and medial thalamic cells,and Purkinje cells and pyramidal cells may be more sensitive to ERS than other types of neurons.Our group's previous study found that ERS induced apoptosis in neurons after the onset of CIRI by regulating proteins such as GRP78,CHOP and caspase-12,but the effects of UPR activation on different cells need to be further investigated.

Investigation on endoplasmic reticulum stress mech-anism of ischemic stroke based on network pharma-cology / 中国药理学与毒理学杂志

OBJECTIVE To investigate the mecha-nism of endoplasmic reticulum stress in cerebral isch-emic stroke from a theoretical perspective based on net-work pharmacology.METHODS GeneCards and OMIM databases were used to screen out the related targets of cerebral ischemic stroke and endoplasmic reticulum stress.And Venny2.1.0 was used to draw Venn's diagram to get the intersecting genes between cerebral ischemic stroke and endoplasmic reticulum stress.String data-base was used to get the protein-protein interaction(PPI)diagram and cytoscape was used for visualization analy-sis.The key genes were screened out by cytohubba plug-in,and enrichment analysis was performed.RESULTS Network pharmacology showed that there were 3744 cerebral ischemic stroke-related targets and 8675 endo-plasmic reticulum stress-related targets.After screening,41 common targets were got.There were 37 nodes,390 edges in the PPI network,namely,there were 37 interact-ing proteins and 390 interacting relationships.The key genes identified by cytohubba plug-in were IL-6,ALB,INS,TNF,AKT1,CASP3,MAPK3,TP53,SIRT1 and VEGF.The biological process involves reaction to oxida-tive stress,the regulation of neuron death,and negative regulation of cell differentiation,etc.;cellular components were related to the membrane raft,smooth endoplasmic reticulum,endoplasmic reticulum lumen and other com-ponents;molecular function aspects were related to sig-naling receptor activator activity,chaperone binding and protease binding.Enrichment analysis of pathway revealed that the intersecting targets were involved in PI3K/Akt pathway and protein processing in endoplasmic reticulum,etc.CONCLUSION The endoplasmic reticu-lum stress in cerebral ischemic stroke is related to the bi-ological processes of reaction to oxidative stress,the reg-ulation of neuron death,and negative regulation of cell differentiation,the mechanism may be related to neuroin-flammation and apoptosis.

Research progress on the mechanism of action of endoplasmic reticulum stress inhibitors / 中国药理学与毒理学杂志

Endoplasmic reticulum stress(ERS)is closely related to the mechanisms of multiple diseases,and regulation of ERS has become a therapeutic target for several diseases.Previous studies by our group have demonstrated that ERS can be alleviated and neuronal cells can be protected by downregulating ERS-related proteins such as GRP78,caspase12 and caspase3.The research on ERS inhibitors has progressed rapidly in recent years,and they can be classified into various types such as molecular chaperones,small molecule compounds and natural products,such as 4-phenylbutyric acid(4-PBA),tauroursodeoxycholic acid(TUDCA)and tumor necrosis factor α-stimulating factor 6(TSG-6),etc.These inhibitors can regulate the ERS signaling pathway through different pathways,such as:silent information regulator 1(SIRT1)promotes the expression of anti-apop-totic proteins by inhibiting the PERK-eIF2α-ATF4-CHOP pathway,thus reducing apoptosis.In addition,SIRT1 deacetylates XBP-1,regulates the IRE1α-XBP1 signaling pathway,and inhibits the expressions of GRP78 and CHOP,thereby reducing the protein load of endoplasmic reticulum(ER)and alleviating ERS;PDE4 inhibitor regu-lates c-Jun-mediated apoptotic pathway,reduces the interaction between IRE1 and TRAF2,and attenuates the level of c-Jun phosphorylation,thereby restoring ER homeostasis.In addition,PDE4 inhibitor activates the antioxidant-acting Nrf-2 pathway,decreases the concen-tration of intracellular calcium ion and reduces the pro-duction of ROS;TSG-6 exerts anti-inflammatory effects by regulating the secretion of inflammatory factors through PERK-eIF-2α-NF-κB p65 and IRE1α-TRAF2-NF-κB p65 signaling pathways.In-depth exploration of the potential mechanism of action of ERS inhibitors is of great signifi-cance for finding ways to treat related diseases by regu-lating ERS.

Crosstalk between activating transcription factor 6 and the inositol-requiring enzyme 1 - X-box binding protein 1 pathway in oxygen-glucose deprivation/reoxygenation-injured HT22 cells / 中华危重病急救医学

Objective:To study the crosstalk between the activating transcription factor 6 (ATF6) and inositol-requiring enzyme 1 (IRE1) - X-box binding protein 1 (XBP1) pathway in oxygen-glucose deprivation/reoxygenation (OGD/R)-injured mouse hippocampal neuronal cell line HT22.Methods:The OGD/R-injured HT22 cell model was used to observe the changes of the indicators of endoplasmic reticulum stress (ERS), cell viability, and apoptosis at different OGD/R time points (0, 3, 6, 12, and 24 hours). HT22 cells in the logarithmic growth phase were randomized into blank control group, control+ATF6 activator (AA147) group, control+IRE1 inhibitor (4μ8c) group, OGD/R model group, OGD/R+AA147 group and OGD/R+4μ8c group (10 μmol/L AA147 or 16 μmol/L 4μ8c was given during the whole process in the AA147 group and 4μ8c group). Western blotting was used to detect the expression of ERS-related proteins [glucose-regulated protein 78 (GRP78), phosphorylated-inositol-requiring enzyme 1 (p-IRE1), and phosphorylated-eukaryotic translation initiation factor-2α (p-eIF2α)], and apoptosis-related proteins (Bcl-2, Bax, caspase-3, and cleaved caspase-3). The mRNA of ERS-related genes, and ATF6 [homocysteine-inducible, endoplasmic reticulum stress-inducible, ubiquitin-like domain member 1 (Herpud1), protein disulfide isomerase associated 4 (Pdia4) and Sel-1 suppressor of lin-12-like (Sel1L)] and spliced XBP1 [XBP1s, include DnaJ heat shock protein family member B9 (Erdj4), Sec24 related gene family, member D (Sec24d) and signal sequence receptor, gamma (Ssr3)] induced transcriptional response-related genes were measured by real-time quantitative polymerase chain reaction (RT-qPCR). A cell counting kit-8 (CCK-8) assay was used to detect the viability of HT22 cells. Immunofluorescence was utilized to test the expression of cleaved caspase-3.Results:Compared with the blank control group, the expression of ERS-related proteins p-IRE1 and p-eIF2α were significantly increased at 12 hours and 3 hours following OGD/R, respectively (p-IRE1/β-actin: 2.09±0.10 vs. 1.00±0.00, p-eIF2α/β-actin: 1.39±0.11 vs. 1.00±0.00, both P < 0.01). The mRNA expressions of ERS-related genes [ATF6, XBP1s, unspliced XBP1 (XBP1u), activating transcription factor 4 (ATF4), CCAAT/EBP homologous protein (CHOP)] were also upregulated in different OGD/R timepoint in HT22 cells, which indicated ERS was activated in OGD/R-stimulated HT22 cells. Compared with the OGD/R model group, the expression of protein p-IRE1 was not changed, but the mRNA of XBP1s and XBP1u were obviously downregulated in the OGD/R+AA147 group [XBP1s (2 -ΔΔCt): 0.76 (0.71, 0.92) vs. 1.13 (1.03, 1.29), XBP1u (2 -ΔΔCt): 0.29±0.05 vs. 0.52±0.04, both P < 0.01], whereas the expressions of XBP1s-induced transcriptional response downstream genes did not change significantly. Compared with the OGD/R model group, the protein of short-form ATF6 (sATF6) and GRP78 were not changed after administration of 4μ8c, neither was the mRNA expression of ATF6-induced transcriptional response-related genes. These results showed that the mRNA expression of XBP1s and XBP1u were inhibited by AA147-induced activation of ATF6, but no crosstalk was observed between the transcriptional response induced by ATF6 and XBP1s. Compared with the blank control group, the cell viability decreased significantly at OGD/R 3 hours [(44.64±5.12) % vs. (99.13±5.76) %, P < 0.01], the ratios of apoptosis-related proteins Bax/Bcl-2 and cleaved caspase-3/caspase-3 were significantly increased at OGD/R 3 hours and OGD 0 hour, respectively (Bax/Bcl-2: 6.15±1.65 vs. 1.00±0.00, cleaved caspase-3/caspase-3: 17.48±2.75 vs. 1.00±0.00, both P < 0.01), which indicated that apoptosis was activated in OGD/R-treated HT22 cells. Compared with the OGD/R model group, the cell viability decreased significantly [(36.52±17.78)% vs. (69.90±9.43)%, P < 0.01], and the ratios of Bax/Bcl-2 and cleaved caspase-3/caspase-3 were significantly upregulated in the OGD/R+AA147 group in HT22 cells (Bax/Bcl-2: 2.06±0.31 vs. 1.10±0.25, cleaved caspase-3/caspase-3: 3.35±0.59 vs. 0.55±0.09, both P < 0.01). Conclusion:Under our experimental conditions, no obvious crosstalk between the transcriptional response induced by ATF6 and XBP1s was observed, while ATF6 activation induced by AA147 suppressed mRNA expression of XBP1s and XBP1u and promoted cell death in OGD/R-treated HT22 cells.

Research progress of transcription activating factor 3 in regulating the alveolar macrophages in acute respiratory distress syndrome / 中华危重病急救医学

Acute respiratory distress syndrome (ARDS) refers to acute diffuse lung injury caused by a variety of intrapulmonary and/or extrapulmonary factors such as infection and trauma. Uncontrolled inflammatory response is the main pathological feature. Different functional states of alveolar macrophages have different effects on inflammatory response. Transcription activating factor 3 (ATF3) is a fast response gene in the early stage of stress. In recent years, it has been found that ATF3 plays an important role in regulating the inflammatory response of ARDS by regulating the function of macrophages. This paper reviews the regulatory effects of ATF3 on alveolar macrophage polarization, autophagy and endoplasmic reticulum stress and its effects on the inflammatory process of ARDS, aiming to provide a new research direction for the prevention and treatment of ARDS.

PRE-084 ameliorated learning and memory impairment in T1DM via regulating neuronal MAM / 西安交通大学学报(医学版)

【Objective】 Diabetic mice could show learning and memory dysfunction, and we aimed to investigate the effect of Sigma-1 receptor agonist, PRE-084, on neurons and cognitive impairment in mice with type 1 diabetes (T1DM). 【Methods】 Twenty mice with T1DM induced by streptozocin, aged 8-10 weeks, and 20 control mice (CON) were randomly divided into four groups (CON+Vehicle, CON+PRE-084, T1DM+Vehicle and T1DM+PRE-084). Mouse primary neurons were cultured in high glucose medium with PRE-084 and control solvent, respectively. The body weight, food and water intake, and fasting blood glucose level of mice in each group were detected and recorded. The learning and memory abilities of mice were detected by new object recognition experiment. The mitochondria-associated endoplasmic reticulum membrane (MAM) structure of neurons in hippocampal CA1 area of mice was detected by transmission electron microscope. And the expression levels of ATP and reactive oxygen species (ROS) in hippocampus of mice were detected by biochemical kit. Cell viability and ROS level of primary neurons were detected by CCK8 and cellular ROS kit. 【Results】 PRE-084 reduced the increase of body weight, food and water intake, and blood glucose caused by diabetes. PRE-084 significantly ameliorated the learning and memory impairment of the mice with T1DM, improved the changes of MAM structure in neurons of hippocampal CA1 area of diabetic mice, increased the level of ATP in hippocampus of diabetic mice, and decreased the increase of ROS expression in diabetic hippocampus and neurons under high glucose conditions. 【Conclusion】 Sigma-1 receptor agonist, PRE-084, could improve learning and memory impairment in the mice with T1DM, which might be related to the structural changes of MAM, the increase of ATP production, and the decrease of ROS production in hippocampal neurons.

The effects and mechanisms of trimethylamine-N-oxide on insulin sensitivity in insulin target cells / 药学学报

Gut microbial metabolite trimethylamine-N-oxide (TMAO) is associated with type 2 diabetes (T2DM). Decreased insulin sensitivity is a significant etiological factor of T2DM. Adipocytes, myocytes, and hepatocytes are the three major target cells for insulin. This study aims to investigate the effects and mechanisms of TMAO on the insulin sensitivity of these target cells. Research results indicate that in different ages of db/db diabetic mice, plasma TMAO levels were increased. TMAO significantly inhibits the insulin signaling pathways in these three major insulin target cells, reduces glucose uptake in 3T3-L1 adipocytes and L6 myocytes and downregulates genes related to gluconeogenesis in primary mouse hepatocytes. Furthermore, in mice with normal insulin sensitivity, elevating plasma TMAO levels to those seen in db/db mice using a minipump results in impaired glucose tolerance and hyperinsulinemia. All animal experiments were carried out with approval of the Experimental Animal Welfare Ethics Committee of the Institute of Materia Medica (Chinese Academy of Medical Sciences and Peking Union Medical College). Mechanistic studies suggest that TMAO exposure increases the levels of endoplasmic reticulum stress-related proteins in these three major insulin target cells. In summary, TMAO directly attenuates insulin sensitivity in insulin target cells, and its mechanism of action may involve enhancing endoplasmic reticulum stress.

Establishment of a prognostic prediction model for pancreatic cancer based on endoplasmic reticulum stress-related genes / 临床肝胆病杂志

ObjectiveTo investigate the role of endoplasmic reticulum stress genes in the prognosis of pancreatic cancer， and to establish a prognostic prediction model based on the prognostic markers for pancreatic cancer. MethodsTranscriptome sequencing data were downloaded from TCGA and GTEx databases， and MsigDB website was used to obtain endoplasmic reticulum stress genes. A univariate Cox regression analysis was performed to obtain the genes associated with the prognosis of pancreatic cancer， and a consensus clustering analysis was used to construct the molecular typing of pancreatic cancer， while the differentially expressed genes between the two subgroups were obtained. A Lasso regression analysis was used to obtain the core genes associated with the prognosis of pancreatic cancer， which were used to construct a prognostic prediction model for pancreatic cancer. Related datasets were obtained from the GEO database to validate the predictive performance of the model. The CIBERSORT analysis was used to investigate the correlation between risk score and immune infiltration. Quantitative real-time PCR was used to measure the expression of genes in pancreatic cancer tissue and cell lines. The independent-samples t test was used for comparison of continuous data between two groups， and the chi-square test was used for comparison of categorical data between groups. Survival was compared using Log-rank test. The predictive value of the model was evaluated by evaluating the area under the ROC curve. ResultsThe endoplasmic reticulum stress genes CEBPB， MARCKS， PMAIP1， and UBXN10 were independent risk factors for the prognosis of pancreatic cancer， and based on the expression characteristics of these genes， the TCGA pancreatic cancer cohort was divided into two subgroups， i.e.， cluster A and cluster B， while the cluster A patients had a significantly shorter overall survival time than the cluster B patients （P<0.01）. The Lasso regression analysis obtained 5 core genes from the differentially expressed genes affecting the prognosis of pancreatic cancer， and the risk scoring system was established as risk score=0.156×CDA+0.135×AHNAK2+0.020×RHOV+0.095×LY6D+0.054×SPRR1B. The ROC curve analysis showed that this model had good overall predictive performance， with the area under the ROC curve of 0.731 at 1 year， 0.712 at 3 years， and 0.686 at 5 years， and the low-risk group based on this model had a significantly longer overall survival time than the high-risk group （χ2=11.733， P=0.001）. The model showed good predictive performance in the external dataset GSE57495. Quantitative real-time PCR results showed that the expression levels of CDA， AHNAK2， RHOV， LY6D， and SPRR1B in 40 pancreatic cancer tissue samples were significantly upregulated compared with those in normal adjacent tissue samples （t=2.529， 2.458， 3.314， 3.583， and 5.082， all P<0.05）. ConclusionThe expression characteristics of CDA， AHNAK2， RHOV， LY6D， and SPRR1B can be used to predict the prognosis of pancreatic cancer， and the high expression levels of these genes are associated with the poor prognosis of pancreatic cancer patients.

Research progress of IRE1α inhibitors / 药学学报

Inositol requiring enzyme 1 alpha (IRE1α), a widespread transmembrane protein in mammals, is an endoplasmic reticulum stress (ER stress) receptor. Among the three signaling pathways of the unfolded protein response (UPR), the IRE1α pathway is the most conservative. And there is a growing body of evidence that the occurrence and development of tumors is closely related to the over-expression of IRE1α. Therefore, the study of the IRE1α inhibitors is of great significance to the discovery of new anti-tumor drugs and has been attracting more and more attention. In the hope of providing ideas for the research of targeting IRE1α for cancer therapy, this paper reviewed the data of representative IRE1α inhibitors, including inhibitory activity, the mechanism of action, structural characteristics, and so on.

Effects of mesencephalic astrocyte-derived neurotrophic factor on sepsis-associated acute kidney injury / 世界急诊医学杂志（英文）

@#BACKGROUND: To determine the protective role of mesencephalic astrocyte-derived neurotrophic factor (MANF) in regulating sepsis-associated acute kidney injury (S-AKI). METHODS: A total of 96 mice were randomly divided into the control group, control+MANF group, S-AKI group, and S-AKI+MANF group. The S-AKI model was established by injecting lipopolysaccharide (LPS) at 10 mg/kg intraperitoneally. MANF (200 μg/kg) was administered to the control+MANF and S-AKI+MANF groups. An equal dose of normal saline was administered daily intraperitoneally in the control and S-AKI groups. Serum and kidney tissue samples were obtained for biochemical analysis. Western blotting was used to detect the protein expression of MANF in the kidney, and enzyme-linked immunosorbent assay (ELISA) was used to determine expression of MANF in the serum, pro-inflammatory cytokines (tumor necrosis factor-α [TNF-α] and interleukin-6 [IL-6]). Serum creatinine (SCr), and blood urea nitrogen (BUN) were examined using an automatic biochemical analyzer. In addition, the kidney tissue was observed for pathological changes by hematoxylin-eosin staining. The comparison between two groups was performed by unpaired Student’s t-test, and statistics among multiple groups were carried out using Tukey’s post hoc test following one-way analysis of variance (ANOVA). A P-value <0.05 was considered statistically significant. RESULTS: At the early stage of S-AKI, MANF in the kidney tissue was up-regulated, but with the development of the disease, it was down-regulated. Renal function was worsened in the S-AKI group, and TNF-α and IL-6 were elevated. The administration of MANF significantly alleviated the elevated levels of SCr and BUN and inhibited the expression of TNF-α and IL-6 in the kidney. The pathological changes were more extensive in the S-AKI group than in the S-AKI+MANF group. CONCLUSION: MANF treatment may significantly alleviate renal injury, reduce the inflammatory response, and alleviate or reverse kidney tissue damage. MANF may have a protective effect on S-AKI, suggesting a potential treatment for S-AKI.

Screening of endoplasmic reticulum stress signature-related genes in gastric cancer and the establishment of prognostic risk models / 肿瘤研究与临床

Objective:To screen the endoplasmic reticulum stress (ERS) signature-related differentially expressed genes (DEG) in gastric cancer and to construct a prognostic risk model based on a bioinformatics.Methods:Transcriptome sequencing data (RNA-seq) of 375 gastric cancer and 32 paracancerous tissue samples downloaded from The Cancer Genome Atlas (TCGA) database and the corresponding clinical information were obtained as training set samples; data of 387 gastric cancer patients (GSE84437) from Gene Expression Omnibus (GEO) database were downloaded as validation set samples. All data were obtained on December 25, 2021. A total of 785 ERS signature-related genes (ERS-RG) were obtained from the GeneCards database. DEG between gastric cancer tissues and paracancerous tissues in the TCGA database was analyzed. The identified gastric cancer DEG were intersected with ERS-RG from the GeneCards database to obtain gastric cancer ERS signature-related DEG, which were analyzed for gene ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment. Univariate Cox proportional risk model was used to screen ERS signature-related DEG with prognostic value in gastric cancer, and LASSO regression analysis was performed to construct a polygenic prognostic risk model, and to calculate the prognostic risk score. The patients in training set and validation set were divided into high-risk group and low-risk group according to the median of the prognostic risk score (2.369); Kaplan-Meier survival analysis was used to compare the overall survival (OS) and to draw time-dependent receiver operating characteristic (ROC) curves of patients in the two groups; nomogram was drawn based on the prognostic independent influencing factors of gastric cancer. The characteristic immune cell infiltration abundance between the two groups was analyzed by using the inverse convolution-based CIBERSORT algorithm. Cytolytic activity scores were calculated by using the geometric mean of granzyme A and perforin 1 expression. According to the median prognostic risk score (2.369) and median tumor mutation burden (TMB) (3.000), all patients with gastric cancer were divided into high risk score-high TMB group, high risk score-low TMB group, low risk score-high TMB group and low risk score-low TMB group to compare the OS of patients in each group.Results:A total of 444 ERS signature-related DEG in gastric cancer including 168 down-regulated genes and 276 up-regulated genes were obtained, which were mainly enriched in biological processes such as protein processing in the endoplasmic reticulum, extracellular matrix (ECM) receptor interactions and unfolded protein responses (all P < 0.05). Univariate Cox regression analysis showed that 12 prognostic-related ERS signature-related DEG in gastric cancer were screened out. LASSO regression analysis was performed to obtain a prognostic risk score = 0.052×NOS3+0.137×PON1+0.067×CXCR4+0.131×MATN3+0.116×ANXA5+0.090×SERPINE1. The results of Kaplan-Meier analysis showed that the OS of the low-risk group in both the training and validation sets was better than that of the high-risk group (all P < 0.01). The results of the time-dependent ROC curve analysis showed that the AUC for the 3-year, 5-year, 8-year OS rates was 0.695, 0.786, 0.698, respectively in the training set, while the AUC for the 3-year 5-year, 8-year OS rates was 0.580, 0.625, 0.627, respectively in the validation set. Multivariate Cox regression analysis showed that prognostic risk score ( HR = 3.598, 95% CI 2.290-5.655, P < 0.001) and tumor stage ( HR = 1.344, 95% CI 1.057-1.709, P < 0.05) were independent factors influencing the prognosis of gastric cancer. Among 375 gastric cancer patients in the TCGA database, the expression levels of ATF6, HSPA5, XBP1 and ATF4 in the high-risk group were higher than those in the low-risk group (all P < 0.05); CIBERSORT results showed that the abundance of activated CD4 memory T cells in the high-risk group was lower than that in the low-risk group, and the abundance of both M0 and M2 macrophages in the high-risk group was higher than that in the low-risk group (all P < 0.05). The expression levels of common immune checkpoints (CD274, CTLA4, TNFRSF9, TIGIT, PDCD1, LAG3) in the high-risk group were all higher than those in the low-risk group (all P < 0.05). Cytolytic activity score in the high-risk group was higher than that in the low-risk group ( P < 0.05). The prognostic risk score was negatively correlated with TMB ( r = -0.20, P < 0.001). Patients in the low-risk score-high TMB group had the best OS and those in the high-risk score-low TMB group had the worst OS (both P < 0.001). Conclusions:The prognostic risk score model is established based on 6 ERS signature-related DEG in gastric cancer and its prognostic risk score may be effective as an independent prognostic factor to predict the prognosis of gastric cancer patients.

Protective effect of polypyrimidine tract-binding protein-associated splicing factor on endoplasmic reticulum oxidative stress injury of human retinal microvascular endothelial cells / 中华眼底病杂志

Objective:To observe the effects of overexpression of polypyrimidine tract binding protein-associated splicing factor (PSF) on the endoplasmic reticulum (ER) oxidative stress damage of human retinal microvascular endothelial cells (hRMEC) under high concentration of 4-hydroxynonenal (4-HNE).Methods:The logarithmic growth phase hRMEC cultured in vitro was divided into normal group, simple 4-HNE treatment group (simple 4-HNE group), empty plasmid combined with 4-HNE treatment group (Vec+4-HNE group), and PSF high expression combined with 4-HNE treatment group (PSF+4-HNE group). In 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group cell culture medium, 10 μmol/L 4-HNE was added and stimulated for 12 hours. Subsequently, the Vec+4-HNE group and PSF+4-HNE group were transfected with transfection reagent liposome 2000 into pcDNA empty bodies and pcDNA-PSF eukaryotic expression plasmids, respectively, for 24 hours. Flow cytometry was used to detect the effects of 4-HNE and PSF on cell apoptosis. The effect of PSF overexpression on the expression of reactive oxygen species (ROS) in hRMEC was detected by 2', 7'-dichlorodihydrofluorescein double Acetate probe. Western blot was used to detect ER oxide protein 1 (Ero-1), protein disulfide isomerase (PDI), C/EBP homologous transcription factor (CHOP), glucose regulatory protein (GRP) 78, protein kinase R-like ER kinase (PERK)/phosphorylated PERK (p-PERK), and Eukaryotic initiation factor (eIF) 2α/the relative expression levels of phosphorylated eIF (peIF) and activated transcription factor 4 (ATF4) proteins in hRMEC of normal group, 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group. Single factor analysis of variance was performed for inter group comparison.Results:The apoptosis rates of the simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were (22.50±0.58)%, (26.93±0.55)%, and (11.70±0.17)%, respectively. The intracellular ROS expression levels were 0.23±0.03, 1.60±0.06, and 0.50±0.06, respectively. The difference in cell apoptosis rate among the three groups was statistically significant ( F=24.531, P<0.05). The expression level of ROS in the Vec+4-HNE group was significantly higher than that in the simple 4-HNE group and the PSF+4-HNE group, with a statistically significant difference ( F=37.274, P<0.05). The relative expression levels of ER Ero-1 and PDI proteins in the normal group, simple 4-HNE group, Vec+4-HNE group, and PSF+4-HNE group were 1.25±0.03, 0.45±0.03, 0.63±0.03, 1.13±0.09, and 1.00±0.10, 0.27±0.10, 0.31±0.05, and 0.80±0.06, respectively. The relative expression levels of CHOP and GRP78 proteins were 0.55±0.06, 1.13±0.09, 0.90±0.06, 0.48±0.04 and 0.48±0.04, 1.25±0.03, 1.03±0.09, 0.50±0.06, respectively. The relative expression levels of Ero-1 ( F=43.164), PDI ( F=36.643), CHOP ( F=42.855), and GRP78 ( F=45.275) proteins in four groups were compared, and the differences were statistically significant ( P<0.05). Four groups of cells ER p-pERK/pERK ( F=35.755), peIF2 α/ The relative expression levels of eIF ( F=38.643) and ATF4 ( F=31.275) proteins were compared, and the differences were statistically significant ( P<0.05). Conclusion:PSF can inhibit cell apoptosis and ROS production induced by high concentration of 4-HNE, and its mechanism is closely related to restoring the homeostasis of ER and down-regulating the activation level of PERK/eIF2α/ATF4 pathway.

Cytopathic effect of rotavirus NSP4 86-175 protein on rat cardiomyocytes and the possible mechanism / 中华微生物学和免疫学杂志

Objective:To investigate the cytopathic effect of amino acids 86-175 of rotavirus non-structural protein 4 (NSP4 86-175) on rat cardiomyocytes and the possible mechanism. Methods:Rat H9C2 cardiomyocytes were treated with NSP4 86-175 protein. Changes in the growth and morphology of the cells were observed. The activity of LDH in the cell culture medium was detected. Fluo-3AM was used to label intracellular free calcium ions and the concentrations of calcium ions in rat cardiomyocytes with and without NSP4 86-175 treatment were detected by confocal laser microscopy. The expression of Bax, Bcl-2, caspase-3, 78 kDa glucose-regulated protein (GRP78), C/EBP homologous protein (CHOP) and caspase-12 at mRNA level was detected by real-time PCR. The expression of caspase-3, caspase-8, caspase-9, GRP78, CHOP and caspase-12 at protein level was detected by Western blot. Results:Normal cardiomyocytes showed a typical myoblast-like morphology, presenting as spindle-shaped cells with clear boundaries. Obvious cytopathic effect, vacuolar degeneration, shriveled and rounded cells, and cell fragmentation were observed after the treatment with purified NSP4 86-175 protein. The activity of LDH in cell culture medium was enhanced by NSP4 86-175 protein. NSP4 86-175 protein also enhanced the fluorescence of the calcium ions in rat cardiomyocytes, promoted cell apoptosis, up-regulated the expression of apoptotic factors including caspase-3, caspase-8, caspase-9 and Bax-2, and increased the expression of classical markers of endoplasmic reticulum stress such as GRP78, CHOP and caspase-12. Conclusions:NSP4 86-175 had a cytopathic effect on rat cardiomyocytes, which might be related to the induced intracellular calcium overload, endoplasmic reticulum stress, apoptosis and necrosis. These results might be used as theoretical reference for further study on rotavirus infection and myocardial injury.

Role of NORAD in ketamine-induced neurotoxicity in mouse hippocampal neurons: association with endoplasmic reticulum stress / 中华麻醉学杂志

Objective:To evaluate the role of long non-coding RNA (lncRNA) NORAD in ketamine-induced neurotoxicity in mouse hippocampal neurons and the relationship with endoplasmic reticulum stress.Methods:Primary mouse hippocampal neurons were isolated and cultured and then divided into 5 groups ( n=36 each) using a random number table method: control group (group C), ketamine group (group K), ketamine+ pcDNA3.1-NORAD plasmid group (group K+ NORAD), ketamine+ control plasmid group (group K+ NC), and ketamine+ NORAD+ tunicamycin group (group K+ NORAD+ TM). Group C was cultured with normal medium for 24 h. Group K was cultured with 40 μmol/L ketamine for 24 h. Group K+ NORAD was transfected with pcDNA3.1-NORAD overexpressing plasmid for 48 h, followed by treatment with 40 μmol/L ketamine for 24 h. Group K+ NC was transfected with pcDNA3.1 (+ ) plasmid for 48 h, followed by treatment with 40 μmol/L ketamine for 24 h. Group K+ NORAD+ TM was transfected with pcDNA3.1-NORAD overexpressing plasmid, 24 h later endoplasmic reticulum stress activator tunicamycin 1 μg/ml was added and the neurons were cultured for 24 h, and then ketamine 40 μmol/L was added and the neurons were cultured for another 24 h. Cell viability was detected by CCK-8 assay. The amount of lactate dehydrogenase (LDH) released was analyzed. Cell apoptosis was determined by TUNEL and flow cytometry methods. The NORAD expression was detected by real-time polymerase chain reaction. The expression of endoplasmic reticulum stress-related proteins protein kinase R-like ER kinase (PERK), phosphorylated PERK (p-PERK) and C/EBP homologous protein (CHOP) was detected by Western blot. Results:Compared with group C, the cell viability was significantly decreased, the amount of LDH released, percentage of apoptotic neurons and apoptosis rate were increased, NORAD expression was down-regulated, CHOP expression was up-regulated, and p-PERK/PERK was increased in group K ( P<0.05). Compared with group K, the cell viability was significantly increased, the amount of LDH released, percentage of apoptotic neurons and apoptosis rate were decreased, NORAD expression was up-regulated, CHOP expression was down-regulated, and p-PERK/PERK was decreased in group K+ NORAD ( P<0.05), and no significant change was found in the parameters mentioned above in group K+ NC ( P>0.05). Compared with group K+ NORAD, the cell viability was significantly decreased, the amount of LDH released, percentage of apoptotic neurons and apoptosis rate were increased, CHOP expression was up-regulated, and p-PERK/PERK was increased ( P<0.05), and no significant change was found in the NORAD expression in group K+ NORAD+ TM ( P>0.05). Conclusions:Over-expressed NORAD can alleviate ketamine-induced neurotoxicity in mouse hippocampal neurons via inhibition of the endoplasmic reticulum stress.