In vitro study on cyclic fatigue resistance of three types of nickel titanium files in preparation for bending root canals / 口腔疾病防治

Objective@#The purpose of this study was to investigate the differences in the anti cyclic fatigue performance of Woride KS (WKS), Proteper Gold (PTG), and Hyflex CM (HCM) nickel titanium instruments with different tip diameters in curved root canal models, and to provide reference for the targeted selection of suitable nickel titanium instruments in clinical preparation of curved root canals.

Role of micronucleus-activated cGAS-STING signaling in antitumor immunity / 浙江大学学报·医学版

cGAS-STING signaling is a significant component of the innate immune system and functions as a vital sentinel mechanism to monitor cellular and tissue aberrations in microbial invasion and organ injury. cGAS, a cytosolic DNA sensor, is specialized in recognizing abnormally localized cytoplasmic double-stranded DNA (dsDNA) and catalytically synthesizes the second messenger cyclic-GMP-AMP (cGAMP), which initiates a cascade of type I interferon and inflammatory responses mediated by STING. Micronucleus, a byproduct of chromosomal missegregation during anaphase, are also significant contributors to cytoplasmic dsDNA. These unstable subcellular structures are susceptible to irreversible nuclear envelope rupture, exposing genomic dsDNA to the cytoplasm, which potently recruits cGAS and activates STING-mediated innate immune signaling and its downstream activities, including type I interferon and classical nuclear factor-κB (NF-κB) signaling pathways lead to senescence, apoptosis, autophagy activating anti-cancer immunity or directly killing tumor cells. However, sustained STING activation-induced endoplasmic reticulum stress, activated chronic type I interferon and nonclassical NF-κB signaling pathways remodel immunosuppressive tumor microenvironment, leading to immune evasion and facilitating tumor metastasis. Therefore, activated cGAS-STING signaling plays a dual role of suppressing or facilitating tumor growth in tumorigenesis and therapy. This review elaborates on research advances in mechanisms of micronucleus inducing activation of cGAS-STING signaling and its implications in tumorigenesis and therapeutic strategies of malignant tumors.

Cell-to-Cell Communications of cGAS-STING Pathway in Tumor Immune Microenvironment / 浙江大学学报·医学版

Targeting cGAS-STING pathway is a promising strategy in tumor treatment. The pattern recognition receptor cGAS identifies dsDNA and catalyzes the formation of the second messenger 2'3'-cGAMP, activating the downstream interferons and pro-inflammatory cytokines through the adaptor protein STING. Notably, in tumor immune microenvironment, key components of cGAS-STING pathway are transferred among neighboring cells. The intercellular transmission under these contexts serves to sustain and amplify innate immune responses while facilitating the emergence of adaptive immunity. The membrane-based system, including extracellular vesicles transport, phagocytosis and membrane fusion transmit dsDNA, cGAMP and activated STING, enhancing the immune surveillance and inflammatory. The membrane proteins, including specific protein channel and intercellular gap junctions, transfer cGAMP and dsDNA, which are crucial to regulate immune responses. And the ligand-receptor interactions for interferons transmission amplifies the anti-tumor response. This review elaborates on the regulatory mechanisms of cell-to-cell communications of cGAS-STING pathway in tumor immune microenvironment. We further explore how these mechanisms modulate immunological processes and discuss potential interventions and immunotherapeutic strategies targeting these signaling cascades.

Mechanism of cGAS/STING Signaling Pathway in Regulating Lung Cancer and Traditional Chinese Medicine Treatment： A Review / 中国实验方剂学杂志

According to the latest global cancer statistics， the incidence and mortality of lung cancer rank first in China. Classical therapies remain the most common cancer treatment options， such as surgical resection， radiotherapy， and chemotherapy， but not all cancer patients respond to classical therapies， which require new lung cancer treatment strategies. After decades of research and development， cancer immunotherapy has achieved certain curative effect， which provides new possibilities for cancer treatment. Cyclic guanosine monophosphate-adenosine monophosphate synthase （cGAS） is a cytosolic DNA sensor. It can induce protective immune defense responses against various DNA-containing pathogens and provide anti-tumor immunity by activating the interferon （IFN） gene stimulator （STING） protein. At present， relevant researchers in China and abroad have done a lot of research on the occurrence and development of lung cancer and the pathophysiological mechanism of drug intervention in the treatment of lung cancer. The results show that cGAS/STING signaling pathway plays an important role in the development of the disease， and traditional Chinese medicine monomers or compounds can intervene in lung cancer cells by regulating the cGAS/STING signaling pathway， induce their autophagy and death， regulate their cycle operation， promote senescence， inhibit their proliferation and tumor angiogenesis， promote their invasion and metastasis， and promote the immune activation of anti-lung cancer cells， so as to inhibit or delay the occurrence and development of lung cancer. In recent years， the related research results have been updated rapidly， and the previous literature has not included the latest research results in time， which causes a lot of inconvenience for many scholars to search the literature. Based on this， this paper mainly summarized the mechanism of cGAS/STING signaling pathway intervention in lung cancer in China and abroad in recent years， as well as the research progress of related traditional Chinese medicine intervention， so as to provide new ideas for the development of lung cancer in molecular biology， drug treatment research， and clinical new drug research and provide a reference for further mechanism research.

CYCLIC AND TORSIONAL FATIGUE RESISTANCE OF THERMALLY TREATED ROTARY NiTiINSTRUMENTS WITH DIFFERENT DESIGNS

Aims: The aim was to evaluate the cyclic and torsional fatigue resistance among thermally treated NiTi rotary instruments with different design features.Materials and methods: Sixty instruments of three systems were used (n=20): TruNatomy 26.04 (TN 26.04), BassiLogic 25.05 (BL 25.05), and Flat File 25.04 (FF 25.04). The cyclic fatigue test (n=10) was performed to evaluate the time to fracture (s) and the number of cycles until failure (NCF). The torsion test was performed to evaluate the torque (N.cm) and maximum angular deflection until fracture (n=10). The fracture surface of each fragment was examined under a scanning electron microscope. The data were analyzed by Tukey's test (p<0.05).Results: BL 25.05 and FF 25.04 instruments had a higher number of cycles and time to fracture compared with TN 26.04 (p<0.05). TN 26.04 instruments showed lower torque to fracture.Conclusions: Based on the proposed objectives and the methodology used, TruNatomy 26.04 instruments present lower resistance to cyclic fatigue and torsional fatigue when compared to BassiLogic 25.05 and Flat File 25.04 instruments.

Shared epitope classification methods according to Gregersen and de Vries allow adequate characterization of patients with rheumatoid arthritis in a Colombian population

Introduction: The most important genetic association in rheumatoid arthritis (RA) is presented with some alleles from the HLA-DRB1 gene that encode the shared epitope (SE). Objectives: To apply the SE classification methods of Gregersen, de Vries, Raychaudhuri, Mattey, and Tezenas du Montcel in a group of Colombian patients with RA and determine the most common HLA-DRB1 alleles in the population. Methods: RA diagnosis, genetic study of the HLA-DRB1 region using Luminex technology in 50 RA and 50 healthy subjects. For the classification analysis, Fisher's exact test and chi-squared test were applied. Tables were created to count the RA-related alleles. We used odds ratio to determine the risk between the presence of the shared epitope (SE) and anti-cyclic citrullinated peptides (Anti-CCP). Results: Gregersen and de Vries methods were suitable for the characterization of RA in this population (p = .006). The most prevalent HLA-DRB1 alleles in the RA group were 14:02,04:04, 08:02,04:05, and 10:01. High frequencies of the 07:01, 03:01,13:02,01:02, and 12:01 HLA-DRB1 alleles were found in the healthy population. HLA-DRB1 alleles with similar distribution in both populations were 04:07, 15:01, 11:01, 16:02, and 01:01. A high frequency of SE + was observed in Anti-CCP + individuals (63.15%); however, this was not statistically significant [OR2.4 (.63-9.01); p = .19]. Conclusion: The SE classification methods of Gregersen and de Vries were adequate in characterizing RA in a Colombian population group. An equivalence of 100% was verified between the susceptibility alleles defined by de Vries and the alleles assigned as SE according to Gregersen.

Introducción: La asociación genética más importante en artritis reumatoide (AR) se presenta con algunos alelos del gen HLA DRB1 que codifican el epítope compartido (EC). Objetivos: Aplicar los métodos de clasificación de EC de Gregersen et al., de Vries et al., Raychaudhuri et al., Mattey et al., y Tezenas du Montcel et al., en un grupo de pacientes colombianos con AR, y determinar los alelos HLA DRB1 más frecuentes en esta población. Métodos: Diagnóstico para AR, estudio genético de la región HLA DRB1 por tecnología Luminex® de 50 sujetos AR y 50 sanos. Para análisis comparativos de clasificaciones EC, se aplicaron las pruebas test exacto de Fisher y Chi-cuadrado y se realizaron tablas de conteos para los alelos relacionados con AR. Se estimó la razón de odds para determinar el riesgo entre la presencia de EC y los anticuerpos antipéptidos cíclicos citrulinados (anti-PCC). Resultados: Los métodos de Gregersen et al. y de Vries et al. fueron adecuados para la caracterización de AR en esta población (p = 0,006). Los alelos HLA DRB1 más prevalentes en el grupo AR fueron 14:02, 04:04, 08:02, 04:05 y 10:01. Se encontraron altas frecuencias de los alelos HLA DRB1 07:01, 03:01,13:02, 01:02 y 12:01 en población sana. Alelos HLA DRB1 con distribución similar en ambas poblaciones fueron: 04:07, 15:01, 11:01, 16:02 y 01:01. Se observó alta frecuencia de individuos EC+ en el grupo AR anti-PCC+ (63,15%); no obstante, sin asociación estadística (OR: 2,4 [0,63-9,01]; p = 0,19). Conclusión: Los métodos de clasificación para EC de Gregersen et al. y de Vries et al. fueron adecuados caracterizando AR en un grupo de población colombiana. Se corroboró equivalencia del 100% entre los alelos de susceptibilidad definidos por de Vries y los alelos asignados como EC según Gregersen et al.

Progress in DNA-sensing pathways in Epstein-Barr virus infection / 中华微生物学和免疫学杂志

Epstein-Barr virus (EBV) is generally susceptible in human beings and multi-organ systems can be involved in EBV infection, such as blood, respiratory, urinary, digestive and nervous systems. EBV infection also plays an important role in the pathogenesis of related tumors, autoimmune diseases and other diseases, posing a great threat to human health. As a DNA virus, EBV can be sensed by DNA recognition receptors to trigger a series of downstream immune responses. A DNA-sensing pathway consists of DNA sensors, adaptor molecules and downstream effector signals. Double-stranded DNA sensors mainly include absent in melanoma 2-like receptors (ALRs) and cyclic GMP-AMP synthase (cGAS). Adaptors were mainly stimulator of interferon genes (STING) and apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC). Downstream immune responses mainly involve typeⅠIFN, inflammasomes and proinflammatory cytokines. As a double-stranded DNA virus of the Herpesviridae family, EBV triggers complex innate and adaptive immune responses in the host, especially the sensing pathways mediated by a variety of DNA recognition receptors, which play a key role in host immune defense and pathogen immune evasion. This review made the DNA sensor as the clue to comprehensively summarize the progress in the activation, regulatory mechanism and clinical relevance of DNA-sensing pathways in EBV infection in recent years, aiming to achieve a better understanding of the host innate immune responses during EBV infection and provide an immunological basis for the prevention and treatment of EBV infection-related diseases.

Progress of cyclic adenosine monophosphate responsive element binding protein in the pathogenesis of drug-resistant epilepsy / 中华神经科杂志

Recent studies have found that in the development of epilepsy, cyclic adenosine monophosphate response element binding protein (CREB) may cause recurrent epilepsy by inhibiting the expression of γ-aminobutyric acid, resulting in neuron damage and weakened effect of antiepileptic drug targets. Antiepileptic drugs can not control the extent or frequency of seizures, and then the patients are in a persistent state, hence the development of drug-resistant epilepsy. Therefore, the mechanism of CREB leading to drug-resistant epilepsy was reviewed in this paper, hoping to provide ideas for the treatment of drug-resistant epilepsy patients.

Effect of edaravone on ERK-CREB signaling pathway in hippocampus of aged rats with postoperative cognitive dysfunction / 中华麻醉学杂志

Objective:To evaluate the effect of edaravone on the extracellular signal-regulated kinase (ERK)-cAMP responsive element binding protein (CREB) signaling pathway in the hippocampus of aged rats with postoperative cognitive dysfunction (POCD).Methods:Sixty SPF healthy male Sprague-Dawley rats, aged 20 months, weighing 650-700 g, were divided into 4 groups ( n=15 each) using a random number table method: control group (group C), POCD group (group P), edaravone group (group E) and ERK inhibitor group (group I). The rats received laparotomy under 3% sevoflurane anesthesia to prepare POCD model in P, E and I groups. Edaravone 3 mg/kg was intraperitoneally injected at 30 min before operation in E and I groups, ERK inhibitor PD98059 0.3 mg/kg was injected via the tail vein in group I. The open field test was performed at 3 days after operation to evaluate the spontaneous activity of rats, then Morris water maze test was performed to evaluate the cognitive function of rats on 3-7 days after operation. The rats were sacrificed after the end of Morris water maze test, and hippocampal tissues were obtained for determination of the expression of phosphorylated ERK (p-ERK), phosphorylated CREB (p-CREB), synaptophysin and postsynaptic density protein 95 (PSD-95) (by Western blot) and dendrite length and density of dendrites in hippocampal CA1 area (using Golgi staining). Results:Compared with group C, the escape latency was significantly prolonged after operation, the number of crossing the original platform was reduced, the expression of p-ERK, p-CREB, synaptophysin and PSD-95 was down-regulated, and the dendritic length and density of hippocampal neurons were reduced in group P ( P<0.05). Compared with group P, the escape latency was significantly shortened, the number of crossing the original platform was increased, the expression of p-ERK, p-CREB, synaptophysin and PSD-95 was up-regulated, and the dendritic length and density of hippocampal neurons were increased in group E ( P<0.05). Compared with group E, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the expression of p-ERK, p-CREB, synaptophysin and PSD-95 was down-regulated, the dendritic length of hippocampal neurons was shortened, and the density of hippocampal neurons was decreased in group I( P<0.05). Conclusions:The mechanism by which edaravone improves POCD may be related to activating ERK/CREB signaling pathway and changing synaptic plasticity in hippocampal CA1 region in aged rats.

Effect of surgery under propofol anesthesia during mid-pregnancy on cognitive function and hippocampal HDAC2-CREB-NR2B signaling pathway in offspring rats / 中华麻醉学杂志

Objective:To evaluate the effect of surgery under propofol anesthesia during mid-pregnancy on the cognitive function and hippocampal histone deacetylase 2 (HDAC2)-cAMP response element-binding protein (CREB)-N-methyl-D-aspartate (NMDA) receptor 2B subunit (NR2B)-containing NMDA receptor (NR2B) signaling pathway in the offspring rats.Methods:Thirty healthy Sprague-Dawley rats at 14 days of gestation were divided into 3 groups ( n=10 each) using a random number table method: propofol anesthesia group (P group), surgery under propofol anesthesia group (S group) and control group (C group). In S group, propofol 20 mg/kg was injected via the caudal vein, and then propofol was continuously infused at a rate of 20 mg·kg -1·h -1 to maintain anesthesia for 4 h, and exploratory laparotomy was performed. Group P received no exploratory laparotomy and the other treatments were similar to those previously described in group S. The equal volume of normal saline was given instead in group C. The learning and memory of the offspring rats was assessed using Morris water maze test on postnatal day 30. The expression of HDAC2, phosphorylated CREB (p-CREB), NR2B, brain-derived neurotriphic factor (BDNF) and phosphorylated tyrosine kinase B (p-TrkB) in offspring′s hippocampi was evaluated by Western blot. Apoptosis in hippocampal neurons was detected by TUNEL staining. Results:Compared with group C, the escape latency was significantly prolonged, the frequency of crossing the original platform was decreased, the time spent in the second quadrant was shortened, the expression of HDAC2 was up-regulated, the expression of p-CREB, NR2B, BDNF and p-TrkB was down-regulated, and the apoptosis rate of the hippocampal neurons was increased in P and S groups ( P<0.05). Compared with P group, the escape latency was significantly prolonged, the frequency of crossing the original platform was decreased, the time spent in the second quadrant was shortened, the expression of HDAC2 was up-regulated, the expression of p-CREB, NR2B, BDNF and p-TrkB was down-regulated, and the apoptosis rate of the hippocampal neurons was increased in S group ( P<0.05). Conclusions:Surgery under propofol anesthesia during mid-pregnancy can decrease the cognitive function of offspring rats, and the mechanism is related to the regulation of HDAC2-CREB-NR2B signaling pathway and the promotion of apoptosis in hippocampal neurons.

Study of 68Ga-NODAGA-RGD PET/CT in predicting short-term efficacy of tyrosine kinase inhibitor in the treatment of distant metastatic differentiated thyroid cancer / 中华核医学与分子影像杂志

Objective:To investigate the clinical application of 68Ga-cyclo( L-arginylglycyl- L-α-aspartyl- D-tyrosyl-N6-(((4, 7-bis(carboxymethyl)-1, 4, 7-triazonan-1-yl)acetyl))- L-lysyl) (NODAGA-RGD) PET/CT to evaluate short-term efficacy of tyrosine kinase inhibitor (TKI) in distant metastatic differentiated thyroid cancer (dmDTC). Methods:From October 2019 to March 2023, 13 dmDTC patients (5 males, 8 females; age: 68(65, 69) years) from Nanjing First Hospital were retrospectively enrolled, of which 9 were clinically confirmed as radioactive iodine-refractory differentiated thyroid cancer (RAIR-DTC) and 4 were dmDTC without radioactive iodine treatment. All patients underwent 68Ga-NODAGA-RGD PET/CT to assess neovascularization of the target lesions (TL), and the SUV max and target background ratio (T/B) were recorded. After 3 months of TKI treatment (anrotinib ( n=9) or apatinib ( n=4)), change rates of the maximum diameter of TL and thyroglobulin (Tg) were measured. The correlation of SUV max, T/B and the change rate of the maximum diameter of TL were analyzed by Spearman rank correlation analysis. ROC curve analysis was performed for the effectiveness of the T/B and TKI therapy, and the difference of the remission rate of lesions was analyzed by Fisher exact test. Results:In 13 patients, 36 TL were measured by 68Ga-NODAGA-RGD PET/CT with SUV max of 5.44(3.43, 7.56) and T/B of 5.25(4.50, 7.23). The change rate of the maximum diameter of TL was -30%(-39%, -21%) and the change rate of Tg was -68%(-96%, -52%). T/B was negatively correlated with the change rate of the maximum diameter of TL after TKI therapy ( rs=-0.46, P=0.005), while SUV max was not correlated with the change rate of the maximum diameter of TL ( rs=0.03, P=0.883). ROC curve analysis showed that the optimal cut-off value for T/B was 4.95, with the AUC of 0.698, the sensitivity of 87.5%, and the specificity of 60.0%. Compared to lesions with T/B<4.95, those with T/B≥4.95 showed higher remission rate (2/14 vs 63.6%(14/22); P=0.006). After 3 months of TKI treatment, the disease control rate was 12/13. Conclusion:68Ga-NODAGA-RGD PET/CT can effectively reflect tumor neovascularization, predict efficacy of TKI therapy, and provide powerful imaging evidence for TKI therapy in dmDTC.

Research progress on biomarkers related to ACPA-negative rheumatoid arthritis / 中国基层医药

Rheumatoid arthritis (RA) is a group of heterogeneous autoimmune diseases with erosive arthritis as the main clinical feature. The pathogenesis of RA remains unclear. Autoantibodies can be detected in blood or synovial fluid in approximately 70% of patients with RA in the early stage of the disease. Anti-citrullinated protein antibody (ACPA) is the most commonly used autoantibody in the diagnosis of RA. However, ACPA is not a specific antibody for RA. The discovery and clinical application of serum ACPA-negative RA biomarkers is of positive significance for the early diagnosis and prognosis improvement of RA. This paper reviews the research progress of ACPA-negative RA biomarkers.

Dock-able linear and homodetic di,tri,tetra and pentapeptide library from canonical amino acids:SARS-CoV-2 Mpro as a case study / 药物分析学报

Peptide-based therapeutics are increasingly pushing to the forefront of biomedicine with their promise of high specificity and low toxicity.Although noncanonical residues can always be used,employing only the natural 20 residues restricts the chemical space to a finite dimension allowing for comprehensive in silico screening.Towards this goal,the dataset comprising all possible di-,tri-,and tetra-peptide com-binations of the canonical residues has been previously reported.However,with increasing computa-tional power,the comprehensive set of pentapeptides is now also feasible for screening as the comprehensive set of cyclic peptides comprising four or five residues.Here,we provide both the com-plete and prefiltered libraries of all di-,tri-,tetra-,and penta-peptide sequences from 20 canonical amino acids and their homodetic(N-to-C-terminal)cyclic homologues.The FASTA,simplified molecular-input line-entry system(SMILES),and structure-data file(SDF)-three dimension(3D)libraries can be readily used for screening against protein targets.We also provide a simple method and tool for conducting identity-based filtering.Access to this dataset will accelerate small peptide screening workflows and encourage their use in drug discovery campaigns.As a case study,the developed library was screened against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)main protease to identify po-tential small peptide inhibitors.

Mechanism of Shaoyaotang in Regulating Water Metabolism and Intestinal Epithelial Permeability in Ulcerative Colitis Through cAMP/PKA/CREB Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the role of cyclic adenosine monophosphate （cAMP）/protein kinase A （PKA）/cAMP-response element binding protein （CREB） signaling pathway in water metabolism and intestinal epithelial permeability in ulcerative colitis （UC） and the intervention mechanism of Shaoyaotang based on the theory of large intestine governing fluids. MethodSixty male SD rats were divided into blank group， model group， mesalazine group （0.42 g·kg-1）， Shaoyaotang low-dose group （11.1 g·kg-1）， Shaoyaotang medium-dose group （22.2 g·kg-1） and Shaoyaotang high-dose group （44.4 g·kg-1）， with 10 in each group. The UC rat model of internal retention of dampness-heat was established by compound factors. The blank group and the model group were given normal saline （ig）. The mesalazine group was given mesalazine （ig）， and Shaoyaotang low-， medium- and high-dose groups were administrated with corresponding doses of Shaoyaotang （ig）. The treatment lasted for 14 days. The diarrhea score and fecal moisture content of rats in each group were observed. The contents of diamine oxidase （DAO） and D-lactic acid in plasma were detected by enzyme-linked immunosorbent assay （ELISA）. The protein expressions of aquaporin （AQP）8， AQP4， ZO-1 and Occludin in colon tissues were detected by immunohistochemistry， while those of cAMP， PKA and CREB in colon tissues were determined by Western blot. ResultCompared with the normal group， the model group had elevated diarrhea score and fecal moisten content （P<0.01）， increased contents of DAO and D-lactic acid in plasma （P<0.01） and decreased protein expressions of ZO-1， Occludin， AQP8， AQP4， cAMP， PKA and CREB in colon （P<0.01）. Compared with the conditions in the model group， the contents of DAO and D-lactic acid in plasma in each administration groups were lower （P<0.01）， while the protein expressions of ZO-1， Occludin， AQP8， AQP4， cAMP， PKA and CREB in colon were higher （P<0.01）. ConclusionShaoyaotang alleviates the diarrhea in UC， probably through activating cAMP/PKA/CREB signaling pathway， up-regulating expressions of AQPs， enhancing tight junctions in intestinal epithelium and thus improving the water metabolism in colon and the intestinal mucosal permeability.

Research progress of cyclic peptide synthesis strategy and its application in new drug development / 药学学报

Protein-protein interaction (PPI) plays an important role in the regulation of life. Most of the PPI interfaces are large and discontinuous, and it is difficult for small molecules to specifically bind to them. Peptides are critical in PPI surface interactions due to their higher affinity and specificity. However, peptides have some defects such as easy hydrolysis by protease and poor membrane permeability. Due to good biocompatibility and chemical diversity, cyclic peptides play an important role in drug discovery. Therefore, the development of efficient cyclic peptide construction methods has become a frontier issue in peptide drug research. In recent years, a series of new progresses have been made in the synthesis strategy and the application of cyclic peptides, providing powerful technical tools for the research and development of cyclic peptide drugs. In this review, the synthesis strategies of cyclic peptides and their application will be reviewed from four aspects: synthesis strategies, property improvement, biological activity and prospect.

Effect of Modified Gegen Qinliantang on TGR5/cAMP/GLP-1 Signaling Pathway in Pancreatic Tissue of Type 2 Diabetes Mellitus db/db Mice / 中国实验方剂学杂志

ObjectiveTo discuss the effect of modified Gegen Qinliantang （MGQT） on blood glucose and lipids and Takeda G protein-coupled receptor 5 （TGR5）-related pathways in pancreatic tissue of obese type 2 diabetes mellitus （T2DM） mice. MethodA total of 10 male specific pathogen free （SPF） m/m mice （7 weeks old） and 50 male SPF （7 weeks old） were adaptively fed for one week in SPF laboratory. The m/m mice were included in the blank group. T2DM was induce d in the 50 db/db mice. The model mice were randomized into the model group， metformin group （0.2 g·kg-1）， high-dose， medium-dose， and low-dose （31.9， 19.1， 6.4 g·kg-1） MGQT groups， with 10 in each group， and the drug dose was10 mL·kg-1. The model group and the blank group received distilled water of the same volume. The administration lasted 12 weeks （once/day）. Fasting blood glucose （FBG） was detected regularly. After 12 weeks of administration， serum levels of glycated serum protein （GSP）， serum glucose （GLU）， total cholesterol （TC）， triglycerides （TG）， high-density lipoprotein cholesterol （HDL-C）， and low-density lipoprotein cholesterol （LDL-C） were detected. Pathological changes in the pancreatic tissue were based on hematoxylin-eosin （HE） staining. Western blot was used to determine the protein expression of TGR5， protein kinase A （PKA）， phosphorylated （p）-PKA， cyclic-AMP response element binding protein （CREB）， p-CREB， proprotein convertase 1/3 （PC1/3）， and glucagon-like peptide-1 （GLP-1） in pancreatic tissues. The level of cyclic adenosine monophosphate （cAMP） in pancreatic tissue was determined by enzyme-linked immunosorbent assay （ELISA）. ResultCompared with the blank group， the model group had pathological changes in pancreatic tissue， high levels of FBG， GSP， GLU， TC， TG， and LDL-C （P<0.01）， low level of HDL-C （P<0.05）， low protein expression of TGR5， p-PKA （Thr197）/PKA， p-CREB （Ser133）/CREB， PC1/3， and GLP-1 in pancreatic tissue （P<0.01）， and low content of cAMP in the pancreas （P<0.01）. Pancreatic tissue lesion in the treatment groups were milder than that in the model group. Both the high-dose MGQT and metformin can reduce the levels of FBG， GSP， GLU， TC， TG， and LDL-C in db/db mice （P<0.05， P<0.01） and increase the level of HDL-C （P<0.01）. Except the GLP-1 protein in the medium-dose MGQT group， the protein expression of TGR5， p-PKA （Thr197）/PKA， p-CREB （Ser133）/CREB， PC1/3， and GLP-1 in the high-dose and medium-dose MGQT groups and the metformin group increased compared with that in the model group （P<0.05， P<0.01）. The content of cAMP in the pancreatic tissue of the high-dose and medium-dose MGQT groups and the metformin group was raised compared with that in model group （P<0.05， P<0.01）. ConclusionMGQT can improve the glucose homeostasis in db/db mice with T2DM by regulating TGR5/cAMP/GLP-1 signaling pathway-related protein expression.

Pathologically Elevated-Cyclic Stretch Suppressed Vascular Smooth Muscle Cell Mitochondrial Biogenesis by Down-regulating PGC1α Expression / 医用生物力学

Objective To investigate the effect of pathologically elevated-cyclic stretch induced by hypertension on mitochondrial biogenesis of vascular smooth muscle cells (VSMCs), and the role of PGC1α in this process. Methods The Flexcell-5000T stretch loading system in vitro was applied to VSMCs with a frequency of 1. 25 Hz and an amplitude of 5% or 15% to simulate the mechanical environment under normal physiological or hypertensive pathological conditions respectively. Western blotting and qPCR were used to detect the expression of PGC1α, citrate synthase and mitochondrial DNA (mtDNA) copy number in VSMCs under normal physiological or hypertensive pathological conditions. VSMCs were treated with PGC1α specific activator ZLN005 to promote PGC1α expression or specific interfering fragment siRNA to inhibit PGC1α expression in order to detect the effect on citrate synthase and mtDNA copy number. Results Compared with 5% physiological cyclic stretch, 15% pathologically elevated-cyclic stretch significantly suppressed the expression of PGC1α, citrate synthase and mtDNA copy number in VSMCs. Compared with control group, the protein expression of PGC1α was significantly decreased and increased respectively. When VSMCs transfected with PGC1α siRNA or incubated PGC1α activator ZLN005, the expression of citrate synthase and mtDNA copy number were also significantly down regulated and up-regulated in VSMCs accordingly. Under physiological cyclic stretch conditions, the protein level of PGC1α was significantly down-regulated by PGC1α siRNA, which also significantly down-regulated citrate synthase expression and mtDNA copy number. The protein expression of PGC1α was significantly up-regulated by ZLN005, which also enhanced the expression of citrate synthase and mtDNA copy number. Conclusions The pathological cyclic stretch induced by hypertension significantly down-regulated the expression of citrate synthase and mtDNA copy number via suppressing the expression of PGC1α, resulting in mitochondrial dysfunction of VSMCs. PGC1α may be a potential therapeutic target molecule to alleviate the progression of hypertension.

Effects of Cyclic Strain on Neural Differentiation of Rat Bone Marrow-Derived Mesenchymal Stem Cells / 医用生物力学

Objective To study the mechanical effects of cyclic strain on neural differentiation of rat bone marrow mesenchymal stem cells (rBMSCs). Methods The rBMSCs were subjected to cyclic strain for 24 hours andthen cultured for 5 days. The expression of neural markers and the phosphorylation of relative signaling pathway proteins were evaluated. The stress distribution on cell surface was analyzed by finite element method. The differentially expressed genes induced by strain were identified by RNA sequencing analysis. Results The 0. 5 Hz strain with 5% magnitude could significantly induce higher expression of neural markers and elevated phosphorylation level of extracellular-signal-regulated kinase (ERK), protein kinase B (AKT) and mammalian target of rapamycin ( mTOR). KEGG pathway analysis showed that the focal adhesion and ECM-receptor interaction were significantly enriched under cyclic strain. Conclusions Cyclic strain could change the interaction of cells with the extracellular matrix ( ECM) and enhance the AKT/ mTOR and ERK pathway, finally promote rBMSC neural differentiation. Knowledge about the impact of mechanical stimulation on BMSC neural differentiation is expected to improve the efficiency of stem cell differentiation, shed light on device design for tissue engineering, and promote clinical application of mesenchymal stem cells in neural issue repair and regeneration.

Effects of scutellarin on neuroinflammation in rats with traumatic brain injury by regulating cGAS/STING signaling pathway / 中国药房

OBJECTIVE To investigate the improvement effects and mechanism of scutellarin （Scu） on neuroinflammation in rats with traumatic brain injury （TBI）. METHODS The modified Feeney method was applied to construct TBI rat model. The rats were randomly grouped into TBI group，Scu low-dose group （40 mg/kg），Scu high-dose group （80 mg/kg），cyclic guanylate- adenylate synthase （cGAS） inhibitor group （cGAS inhibitor RU.521，450 μg/kg），with 24 rats in each group. Other 24 rats were included in the sham operation group. The modified neurological deficit score （mNSS） method was applied to assess the neurological function of rats； the brain water content of rats was measured by dry/wet specific gravity method； hematoxylin-eosin and TdT-mediated dUTP nick-end labeling staining were applied to observe the pathological changes and apoptosis of brain tissue in rats； the levels of interferon-β （IFN-β），CXC chemokine ligand-10 （CXCL10），tumor necrosis factor-α （TNF-α） and interleukin-6 （IL-6） in rat brain tissue were detected by enzyme-linked immunosorbent assay； Western blot method was applied to detect the expression of cGAS/interferon gene stimulating protein （STING） signal pathway-related proteins in brain tissue of rats. RESULTS Compared with the sham operation group，the mNSS，brain water content，apoptosis rate，the contents of IFN-β，CXCL10，TNF-α and IL-6，and the relative expressions of cGAS and STING proteins in TBI group increased significantly （P＜0.05）； there were edema，bleeding and pathological damage to neurons in the brain tissue. Compared with TBI group，the above indicators and pathological changes of rats in administration groups were improved significantly （P＜0.05），and the effect of Scu was in a dose- dependent manner （P＜0.05）； however，there was no statistically obvious difference in the above indicators between the Scu high- dose group and the cGAS inhibitor group （P＞0.05）. CONCLUSIONS Scu may alleviate neuroinflammation，reduce brain tissue damage and apoptosis，and promote the recovery of neural function in TBI rats by inhibiting the activation of cGAS/STING signaling pathway.

Guiqi Baizhu Prescription Combined with Oxaliplatin Protects Intestinal Barrier of Tumor-bearing Mice with Gastric Cancer by Regulation of VIP/cAMP/PKA/AQP Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the protective effect of Guiqi Baizhu prescription combined with oxaliplatin on the intestinal barrier of tumor-bearing mice with gastric cancer by regulating downstream aquaporin 3 （AQP3） and aquaporin 4 （AQP4） through the vasoactive intestinal peptide （VIP）/cyclic adenosine monophosphate （cAMP）/protein kinase A （PKA） signaling pathway. MethodThe gastric cancer cell lines MFC with a density of 1×107/mL were prepared into cell suspension. The tumor-bearing mouse model of gastric cancer was established by inoculating 0.2 mL cell suspension under the right axilla of mice. After successful modeling， mice were randomly divided into 5 groups， namely， model group， oxaliplatin group （10 mg·kg-1）， and high， medium， and low-dose oxaliplatin + Guiqi Baizhu prescription groups （17.68， 8.84， 4.42 g·kg-1）， with 10 mice in each group， and the remaining 10 mice were set as a blank group. Mice in each group were treated with Chinese medicine， oxaliplatin， or normal saline by gavage or intraperitoneal injection for 14 d. The next day after the last dose， blood was taken from the eyeball to separate serum and take colonic samples. Hematoxylin-eosin （HE） staining was used to observe the changes in tissue morphology. The content of D-lactate acid （D-LA） and diamine oxidase （DAO） in the serum was determined by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein expressions of VIP， cAMP， PKA， AQP3， and AQP4 were detected by Real-time quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the blank group， the model group showed edema in the colonic submucosa， disordered arrangement of intestinal glands in the mucosal layer， loss of goblet cells， infiltration of inflammatory cells， and villus shedding. However， there were different degrees of improvement in each administration group. As compared with the blank group， the serum levels of DAO and D-LA in the model group were significantly increased （P<0.01）. As compared with the model group， the levels of DAO and D-LA in the high-dose oxaliplatin + Guiqi Baizhu prescription group and the level of D-LA in the medium-dose oxaliplatin + Guiqi Baizhu prescription group were decreased （P<0.05， P<0.01）. As compared with the oxaliplatin group， the levels of D-LA in the high and medium-dose oxaliplatin + Guiqi Baizhu prescription groups were decreased （P<0.05）， and the levels of DAO and D-LA in other administration groups were decreased as well， but the difference had no statistical significance. As compared with the blank group， the mRNA and protein expression levels of VIP， cAMP， PKA， AQP3， and AQP4 in the model group were significantly decreased （P<0.05， P<0.01）. As compared with the model group， the mRNA and protein expression levels of VIP， cAMP， PKA， AQP3， and AQP4 in each administration group were increased， and those in the high-dose oxaliplatin + Guiqi Baizhu prescription group were significantly increased （P<0.05， P<0.01）， while the protein expression level of cAMP in the medium-dose oxaliplatin + Guiqi Baizhu prescription group were increased （P<0.05）. As compared with the oxaliplatin group， the protein expression levels of cAMP in the high-dose oxaliplatin + Guiqi Baizhu prescription group were increased （P<0.05）， and the mRNA and protein expressions of these indexes in the other groups were also increased but the differences were not statistically significant. ConclusionGuiqi Baizhu prescription combined with oxaliplatin can regulate AQP3 and AQP4 through the VIP/cAMP/PKA signaling pathway to protect the intestinal barrier of tumor-bearing mice with gastric cancer.