Dephosphorylation of cGAS by PPP6C impairs its substrate binding activity and innate antiviral response

The cyclic GMP-AMP (cGAMP) synthase (cGAS) plays a critical role in host defense by sensing cytosolic DNA derived from microbial pathogens or mis-located cellular DNA. Upon DNA binding, cGAS utilizes GTP and ATP as substrates to synthesize cGAMP, leading to MITA-mediated innate immune response. In this study, we identified the phosphatase PPP6C as a negative regulator of cGAS-mediated innate immune response. PPP6C is constitutively associated with cGAS in un-stimulated cells. DNA virus infection causes rapid disassociation of PPP6C from cGAS, resulting in phosphorylation of human cGAS S435 or mouse cGAS S420 in its catalytic pocket. Mutation of this serine residue of cGAS impairs its ability to synthesize cGAMP upon DNA virus infection. In vitro experiments indicate that S420-phosphorylated mcGAS has higher affinity to GTP and enzymatic activity. PPP6C-deficiency promotes innate immune response to DNA virus in various cells. Our findings suggest that PPP6C-mediated dephosphorylation of a catalytic pocket serine residue of cGAS impairs its substrate binding activity and innate immune response, which provides a mechanism for keeping the DNA sensor cGAS inactive in the absence of infection to avoid autoimmune response.

Dephosphorylation of cGAS by PPP6C impairs its substrate binding activity and innate antiviral response

The cyclic GMP-AMP (cGAMP) synthase (cGAS) plays a critical role in host defense by sensing cytosolic DNA derived from microbial pathogens or mis-located cellular DNA. Upon DNA binding, cGAS utilizes GTP and ATP as substrates to synthesize cGAMP, leading to MITA-mediated innate immune response. In this study, we identified the phosphatase PPP6C as a negative regulator of cGAS-mediated innate immune response. PPP6C is constitutively associated with cGAS in un-stimulated cells. DNA virus infection causes rapid disassociation of PPP6C from cGAS, resulting in phosphorylation of human cGAS S435 or mouse cGAS S420 in its catalytic pocket. Mutation of this serine residue of cGAS impairs its ability to synthesize cGAMP upon DNA virus infection. In vitro experiments indicate that S420-phosphorylated mcGAS has higher affinity to GTP and enzymatic activity. PPP6C-deficiency promotes innate immune response to DNA virus in various cells. Our findings suggest that PPP6C-mediated dephosphorylation of a catalytic pocket serine residue of cGAS impairs its substrate binding activity and innate immune response, which provides a mechanism for keeping the DNA sensor cGAS inactive in the absence of infection to avoid autoimmune response.

Development of Plant Metabolomics Analytical Approach Based on Liquid Chromatography Tandem Mass Spectrometry in Artemisia rupestris L / 分析化学

Due to the diversity and complexity, the change of chemical components in medicinal plant according to the time, cultivated varieties or ecological condition is difficult to recognize using traditional phytochemistry method. In order to analyze the pharmacodynamics material basis in Uighur medicinal plant Artemisia rupestris L. in an effective and comprehensive way, a plant metabolomics approach was established based on liquid chromatography-tandem mass spectrometry (LC-MS/MS). This study firstly focused on the effect of extraction solvents,redissolve solvents and ultrasonic time on the untargeted metabolomics, then the optimal preparation condition was selected according to metabolites coverage. After methodology validation, the approach was applied to acquire metabolic information in root, stem, branchlet, leaf and flower of Artemisia rupestris L. The results showed that the metabolome in flower was obviously different with the other organs. Coupling with multivariate statistical analysis, a batch of differential metabolites were picked out, in which 61 flavonoids, 97 rupestonic acid derivatives, 7 chlorogenic acids and 15 other compounds were primarily recognized according to the characteristic fragmentation rules of specific structure type and database retrieval. Additionally,the distribution characteristics of the above 180 differential metabolites was illustrated by cluster heat map. In conclusion,this study provided important information about the rational utilization of effective parts from Artemisia rupestris L.,and offered a novel strategy for quality control,variety improvement and reasonable development of medicinal plants.

Study on Tissue Distribution of A Variety of Endogenous Metabolites by Air Flow Assisted Ionization-Ultra High Resolution Mass Spectrometry Imaging / 分析化学

As a promising new molecular imaging technique,mass spectrometry imaging(MSI) has attracted more and more attention in the field of biomedicine. A method of air flow assisted ionization-ultra high resolution mass spectrometry-based mass spectrometric imaging (AFAI-MSI) was developed to profile endogenous metabolites in rat kidney tissue in this study. Rat kidneys were collected and cut into frozen tissue sections,and then were analyzed on an AFAI-MSI system in positive ion mode using acetonitrile-isopmpyl alcohol-water (4:4:2,V/V,5 μL/min) as spray solvent,N2as spray gas(0.6 MPa) and air as assisting gas (45 L/min). The mass range and resolution were set to be 70-1000 Da and 70000, respectively. As a result,a total of 38 metabolites, including organic amines, sugars, vitamins, peptides, neurotransmitters, organic acids,phospholipids,sphingolipids,glyceride,and cholesterol esters, were identified and imaged to characterize their tissue-specific distribution in kidney tissues, and some metabolites, such as choline, acetylcoline,betaine,phoshocholine,and glycerophosphocholine were found to have distinct distribution along the cortex-medulla axis,which may be involved in the formation of osmotic pressure gradient in the kidney. The proposed ultra high resolution mass spectrometry based AFAI-MSI method could work without sample pretreatment, showed high sensitivity and wide metabolite coverage, and was expected to provide a new analytical approach for the research of in situ characterization and metabolic regulation mechanism of endogenous metabolites in kidney.

Therapeutic Role of Tangshenkang Granule () in Rat Model with Diabetic Nephropathy / 中国结合医学杂志

<p><b>OBJECTIVE</b>To evaluate the renal protective effect of Tangshenkang Granule () in a rat model of diabetic nephropathy (DN).</p><p><b>METHODS</b>Forty male Sprague-Dawley rats were randomly divided into control, DN, Tangshenkang and benazepril groups. DN model was established in the rats of DN, Tangshenkang and benazepril groups. Tangshenkang Granule solution and benazepril hydrochloride solution were intragastrically administered daily to the rats in the Tangshenkang and benazepril groups for 8 weeks, respectively. Urinary albumin and creatinine were detected. The albumin/creatinine (ACR) was calculated in addition to 24 h urinary protein (24-h UPr), serum creatinine (Scr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and creatinine clearance rate (Ccr). Right kidneys were harvested for pathological observation using periodic acid-silver methenamine-Masson staining. The average glomerular diameter (DG), average glomerular (AG) and mesangial areas (AM) were measured. The thickness of glomerular basement membrane (TGBM) was detected using transmission electron microscope.</p><p><b>RESULTS</b>Compared with rats in the control group, rats in the DN group showed significantly decreased body weight, increased hypertrophy index, 24-h urinary volume, 24-h UPr, ACR, Scr, BUN, Ccr, blood lipids as well as renal pathological indices including DG, AG, AM, AM/AG and TGBM (P <0.05). Compared with the DN group, the weights of rats in the Tangshenkang and benazepril groups were significantly increased, and the renal hypertrophy indices were significantly decreased (P <0.05). The 24-h urinary volumes, ACR, 24-h UPr, Scr, BUN, Ccr, LDL, DG, AG, AM and TGBM were obviously decreased (P <0.05). Compared with the benazepril group, the Tangshenkang group showed significantly decreased levels of ACR, 24-h UPr, AG and AM (P <0.05).</p><p><b>CONCLUSIONS</b>Tangshenkang Granule decreased the urinary protein, attenuated the high glomerular filtration rate and improved lipid metabolism in DN rats, and prevented further injury induced by diabetic nephropathy.</p>

Research progress and application of head finite element model / 医用生物力学

The finite element method (FEM) is a technology for numerical analysis which based on the development of the electronic computer, and also a more advanced biomechanical research method. Early FEM was applied in the fields of engineering science and technology. In recent years, FEM has been widely used for brain research in biomedical engineering. With the rapid development of traffic and transportation, the high incident of craniocerebral injury has become a serious threat to human health year by year. The biomechanical mechanism of craniocerebral injury can be well researched by establishing the finite element model of human head. In this review, establishment, development and application of human head finite element model are summarized, and the future research direction is discussed as well.

Research progress and application of head finite element model / 医用生物力学

The finite element method (FEM) is a technology for numerical analysis which based on the development of the electronic computer,and also a more advanced biomechanical research method.Early FEM was applied in the fields of engineering science and technology.In recent years,FEM has been widely used for brain research in biomedical engineering.With the rapid development of traffic and transportation,the high incident of craniocerebral injury has become a serious threat to human health year by year.The biomechanical mechanism of craniocerebral injury can be well researched by establishing the finite element model of human head.In this review,establishment,development and application of human head finite element model are summarized,and the future research direction is discussed as well.

Drug Discovery Investigation of Nourishing Kidney-yin And Warming Kidney-yang Granules in Prevention And Treatment of Primary Osteoporosis Based on Theory of "Treating Both Disease And Traditional Chinese Medicine Syndrome" / 世界科学技术-中医药现代化

Nourishing kidney-yin (NKY) granules and warming kidney-yang (WKY) granules represent one of the prescriptions that prescribed in treating primary osteoporosis (POP) in light of tonifying kidney and nourishing essence principle as well as the theory of "treating both the disease and traditional Chinese medicine (TCM) syndrome".Both granules were created through the systematic analysis of clinic prescriptions by Professor Shi Qi.Consequently clinical investigations have well established that NKY granules significant improved bone mineral density (BMD) as well as relieved the kidney-yin deficiency syndromes in POP patients.Meanwhile,WKY granules relieve kidney-yang deficiency syndrome and the quality of life (QOL).What is more,pharmacological study established the application of common cnidium fruit,and fructus ligustri lucidi alleviated bone loss in OVX-induced mice.In addition,investigation with effective components identified that both NKY and WKY granules play systematic pharmacological effects on bone remodeling by regulating the expression of BMP/Smad,Wnt/β-catenin,RANKL/RANK/OPG axis,and Notch.The drug discovery was performed by the lead of traditional Chinese medicine (TCM) theory.It is one successful transformation investigation based on pharmacological effects,clinical intervention,animal model,cell culture and molecular investigation.

Shen (Kidney)-tonifying principle for primary osteoporosis: to treat both the disease and the Chinese medicine syndrome / 中国结合医学杂志

Primary osteoporosis (POP) is one of the most common diseases in the elderly people resulting in high risk of fracture and poor quality of life. In addition to the pathological changes in bone mass, most of the POP patients also suffer from Chinese medicine (CM) syndromes of Shen (Kidney) essence deficiency. Shen essences are highly related to bone. Shen essence deficiency plays an important part in the development of POP and a better diagnosis of POP could be made by combining CM syndromes with Western medicine risk factors. Treatments of POP should aim at both increasing the bone mass and relieving the syndromes of Shen essence deficiency. Clinical study confirmed that treating POP patients with Shen-tonifying herbs could increase the bone mass and relieve the CM syndromes of POP patients. Basic researches clarified the mechanism by which Shen-tonifying herbs increased bone mass in animal models. The mechanisms by which Shentonifying herbs relieve the CM syndromes are still in investigation.

Research Progress on Lower Back Pain and Spinal Stability Theory / 世界科学技术-中医药现代化

Lower back pain refers to the pain in the lower back. It usually refers to the region below the lower costal margin on the back. The pain mostly occurs on L4 and L5, or L5 and L1, which is usually called as lower back pain. For the treatment of low back pain, it has lacked the effective and objective measurement methods based on the functional and structural features of spinal muscles. This article discussed on the core stability and core strength, the identification and classification of core muscle group, the relation between core stabilizing muscle group and low back pain. It also discussed the characteristics and effects of training motion therapy in the improving of core strength. The core of human body was consisted of waist, pelvis and hip joint. Core stabilizing training can effectively stabilize the spine and transmit power. The question of how to train and improve the core strength to relieve low back pain and make effective evaluation according to its therapeutic results are the key points in the future study.

Effects of Yiqi Huayu prescription on knee cartilage degeneration in HIF-1alpha gene knockout mice / 中国骨伤

<p><b>OBJECTIVE</b>To study the role of hypoxia-inducible factor 1 alpha (HIF1alpha) on knee cartilage degeneration,and to explore the effects and mechanisms of Chinese herbal compound Yiqi Huayu prescription on HIF-1alpha gene knockout mice on knee cartilage degeneration.</p><p><b>METHODS</b>The 4-month and 6-month HIF-1alpha gene knock out mice were obtained by interbreeding, and divided into HIF-1alpha +/+ 4-month mice group,HIF-1alpha -/- 4-month mice group,HIF-1alpha +/+ 6-month mice group and HIF-1alpha -/- 6-month mice group, 3 mice in each group. And then the 2-month-old HIF-1alpha gene knock out mice were randomly divided into Yiqi Huayu prescription group and physiological saline group. There were 6 mice in each group. After 2 months' drug administration, the knee joint of mice was collected, and the Mankin score were evaluated; Safranine-fast green staining, HE Staining, and immunohistochemistry analysis for VEGF, Col X, Col II, MMP-13 and Sox-9 were performed erespectively.</p><p><b>RESULTS</b>(1) Compared to the results in the HIF-1alpha+/+ mice groups, the HIF-1alpha-/- mice developed aging related cartilage loss and bony tissue appearance, cartilage defects increased,and cells reduced. In HIF-1alpha-/-4-month mice and 6-month mice group, the expresion of Col II and Sox9 decreased, and the expression of Col X, MMP-13 and VEGF increased. (2) Compared to the physiological saline group, the ossification and defect of knee joint cartilage reduced of mice in the Yiqi Huayu prescription group, the cartilage cell distribution was more uniform, and the total number of cells increased. The expression of type II collagen and Sox9 protein increased, expression of Col X, MMP-13 and VEGF protein decreased of mice in the Yiqi Huayu prescription group.</p><p><b>CONCLUSION</b>The knee cartilage degenerates in the HIF-1alpha cKO mice, and the degeneration increased with age adding. The Yiqi Huayu prescription can delay the degeneration of knee cartilage of HIF-1alpha cKO mice.</p>

Experimental study on lumbar intervetebral disc degeneration model with kidney deficiency by ovariectomizing / 中国骨伤

<p><b>OBJECTIVE</b>To observe effects of removing arms and ovarian on lumbar intervertebral disc and vertebral bone mineral density (BMD) by establishing rat model of lumbar intervetebral disc degeneration (IDD) with kidney deficiency, and to explore internal mechanism of disc degeneration, relationship between disc degeneration and osteoporosis.</p><p><b>METHODS</b>Thirty Sprague-Dawley female rats aged one month were randomly divided into control group, lumbar IDD group and lumbar IDD with kidney deficiency group (combined group), 10 rats in each group. Lumbar IDD group removed double arms, lumbar IDD with kidney deficiency group removed double arms after 3 months, both ovaries were removed. Vertebral bone mineral density were observed by Micro-CT scan; morphological changes were tested by safranine O-fast green staining; II, X collagen protein expression in the intervertebral disc were obsevered by immunohistochemistry; extracellular matrix gene expression were obsevered by real-time polymerase chain reaction (RT-PCR), in order to evaluate the effects of removed of forelimbs and double ovarian on degeneration and vertebral bone mineral density of intervertebral disc.</p><p><b>RESULTS</b>Micro-CT scan showed osteoporosis in kidney deficiency group was obviously worse than other two groups; safranine O-fast green staining showed that intervertebral space became narrowed, intervertebral disc tissue degenerated obviously, chondral palte was underdeveloped in kidney deficiency group; immunohistochemistry showed that X collagen expression increased, type II collagen expression decreased in kidney deficiency group; RT-PCR showed that type II collagen expression in lumbar IDD group and kidney deficiency group was lower than control group, and had statistical meaning among three groups (P=0.000, P=0.000); Age 1 in lumbar IDD group and kidney deficiency group was lower than control group, and had statistical meaning among three groups (P=0.000, P= 0.000); while type X collagen expression was higher than control group, but no significant meaning; MMP-13 in lumbar IDD group and kidney deficiency group was higher than control group, with significant meaning compared among three groups (P= 0.000, P=0.000); aggrecanase-2 in lumbar IDD group and kidney deficiency group was higher than control group, with significant meaning compared among three groups (P=0.006, P=0.008).</p><p><b>CONCLUSION</b>Rats model of lumbar disc degeneration established by removed forelimbs and ovariectomized can occure "bone like"--osteoporosis, which is similar with clinical kidney lumbar disc degeneration in tissue morphology, molecular cell biology expression.</p>

USP2a positively regulates TCR-induced NF-κB activation by bridging MALT1-TRAF6

The paracaspase MALT1 is essential for the activation of NF-κB in response to T cell receptor (TCR) stimulation. It recruits downstream TRAF6 and activates the E3 ligase activity of TRAF6 to polyubiquitinate several targets, which ultimately leads to NF-κB activation. Here we identified ubiquitin-specific protease 2a (USP2a) as a MALT1-associated protein by biochemical affinity purification. Endogenous USP2a constitutively interacted with TRAF6, but dynamically interacted with MALT1 and CARMA1 in a stimulation-dependent manner. RNA interference (RNAi)-mediated silencing of USP2a attenuated TCR-induced NF-κB activation and production of interleukin-2 (IL-2). In addition, the ubiquitination of MALT1 and TRAF6 were both suppressed by USP2a knockdown. By knockdown and reconstitution assays, we found that USP2a mediated the interaction between MALT1 and TRAF6 in a catalytic activity-dependent manner. Furthermore, USP2a deSUMOylated TRAF6. Our findings implicate that USP2a plays an important role in TCR signaling by deSUMOylating TRAF6 and mediating TRAF6-MALT1 interaction.

Heat shock cognate 71 (HSC71) regulates cellular antiviral response by impairing formation of VISA aggregates

In response to viral infection, RIG-I-like RNA helicases detect viral RNA and signal through the mitochondrial adapter protein VISA. VISA activation leads to rapid activation of transcription factors IRF3 and NF-κB, which collaborate to induce transcription of type I interferon (IFN) genes and cellular antiviral response. It has been demonstrated that VISA is activated by forming prion-like aggregates. However, how this process is regulated remains unknown. Here we show that overexpression of HSC71 resulted in potent inhibition of virus-triggered transcription of IFNB1 gene and cellular antiviral response. Consistently, knockdown of HSC71 had opposite effects. HSC71 interacted with VISA, and negatively regulated virus-triggered VISA aggregation. These findings suggest that HSC71 functions as a check against VISA-mediated antiviral response.

Intervertebral disc degeneration in hypoxia-inducible factor 1 alpha-knockout mice and treatment of Yiqihuayu Prescription / 中国组织工程研究

10.3969/j.issn.2095-4344.2013.24.016

Effect of dexmedetomidine on stress responses during extubation in patients undergoing uvulopalatopharyngoplasty / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To observe the effect of dexmedetomidine hydrochloride on stress responses during extubation in patients undergoing uvulopalatopharyngoplasty (UPPP).</p><p><b>METHODS</b>Eighty-six scheduled for UPPP under general anesthesia were randomly divided into dexmedetomidine group (group D, n = 50) and control group (group C, n = 36). All patients were transported into post anesthesia care unit (PACU) after surgery and maintained sedation and analgesia by infusing propofol and sufentanil. Patients in group D were administrated dexmedetomidine 0.5 µg/kg, group C were administrated equivalent volume of normal saline. Both groups were treated with mechanical ventilation 6 - 24 h before extubation. Recovery time, the dosage of sedative and analgesic drugs and side effects were recorded.</p><p><b>RESULTS</b>There were no significant differences between two groups in recovery time (P > 0.05). The dosage of propofol and sufentanil in group D were respectively (785 ± 65) mg, (176 ± 10) µg, significantly less than that in group C (950 ± 101) mg, (209 ± 14) µg (P < 0.05). side effects in group D were significantly less than that in group C (P < 0.01).</p><p><b>CONCLUSIONS</b>Dexmedetomidine hydrochloride could efficiently restrain the stress response around tracheal extubation, reduce postoperative complications in patients undergoing UPPP.</p>

Realgar-induced apoptosis of cervical cancer cell line Siha via cytochrome c release and caspase-3 and caspase-9 activation / 中国结合医学杂志

<p><b>OBJECTIVE</b>To explore the molecular mechanism of realgar-induced apoptosis of cervical cancer cells.</p><p><b>METHODS</b>The cervical cancer cell line Siha was used to determine the cell viability and apoptosis after treatment with realgar using MTT assay and flow cytometry. The activities of caspase-3, -8, and -9 were detected by fluorescence resonance energy transfer technology and colorimetric assay, while the levels of Bcl-2, cytochrome c, and Bax were detected by Western blot method.</p><p><b>RESULTS</b>Induction of apoptosis by realgar was detected in Siha cell line in a dose-dependent manner. The apoptosis was accompanied by a significant increase in cytochrome c release and activation of caspase-3 and caspase-9 but not caspase-8. Further, the realgar-induced apoptosis was inhibited by a broad-spectrum caspase inhibitor, a caspase-3 inhibitor, and a caspase-9 inhibitor but not by a caspase-8 inhibitor. Bcl-2 and Bax protein expressions were not changed by realgar.</p><p><b>CONCLUSION</b>The induction of apoptosis by realgar is mediated through a cytochrome c-dependent pathway, which sequentially activates caspase-9 and caspase-3.</p>

MLL1/WDR5 complex in leukemogenesis and epigenetic regulation / 癌症

MLL1 is a histone H3Lys4 methyltransferase and forms a complex with WDR5 and other components. It plays important roles in developmental events, transcriptional regulation, and leukemogenesis. MLL1-fusion proteins resulting from chromosomal translocations are molecular hallmarks of a special type of leukemia, which occurs in over 70% infant leukemia patients and often accompanies poor prognosis. Investigations in the past years on leukemogenesis and the MLL1-WDR5 histone H3Lys4 methyltransferase complex demonstrate that epigenetic regulation is one of the key steps in development and human diseases.

Effect of paeonol on proliferation of human ovarian cancer cell line A2780s / 肿瘤

Objective: To investigate the effect of paeonol (Pae) on the proliferation of human ovarian cancer cell line A2780s in vitro. Methods: Inhibitory effects of Pae with different concentrations on A2780s cells were detected by MTT assay. The cell cycle distribution and the apoptosis rate of A2780s cells were determined by flow cytometry (FCM). Results: The proliferation of A2780s cells was significantly inhibited after treatment with Pae (7.81-250.00 mg/L) in a concentration- and time-dependent manner. FCM results showed that the proportion of cells in S phase was increased while which in G0/G1 phase and G2/M phase were decreased after treatment with Pae (31.25-250.00 mg/L) for 48 h. The apoptosis rate of A2780s cells induced by Pae was increased in a concentration-dependent manner. Conclusion: Pae can inhibit the proliferation and induce the apoptosis of human ovarian cancer cells.

Expression of transforming growth factor-beta 1 and connective tissue growth factor in women with pelvic organ prolapse

To investigate the presence of transforming growth factor-beta 1 [TGF-beta 1] and connective tissue growth factor [CTGF] in women with pelvic organ prolapse [POP]. This study was conducted from May to December 2009. Fifty patients with POP that underwent vaginal hysterectomy in the Department of Gynecology, Renmin Hospital of Wuhan University, Hubei, Wuhan, China were enrolled in this study. They were divided into: Group 1 [n-10]; Group 2 [n=10]; and Group 3 [n=10] according to Pelvic Organ Prolapse Quantitation [POP-Q]. Meanwhile, 20 cases treated by vaginal hysterectomy for other benign gynecological diseases were selected as the control group. Immunohistochemical staining and Western blot were performed to detect the expression of TGF-beta 1 and CTGF. Immunohistochemical staining of TGF- beta 1 and CTGF were mainly expressed in the cytoplasm of fibroblast cells. The expression of TGF- beta 1 and CTGF protein was significantly negatively correlated with POP-Q stage. There were significantly positive correlations between the expression of TGF- beta 1 and CTGF protein. The expression of TGF- beta 1 protein among the 3 POP groups were all significantly lower than that of the control group, while there was no significant differences in the expression of TGF- beta 1 protein among the POP groups, excluding the comparison between Groups 1 and 3. The expression of CTGF protein in the 3 POP groups were all significantly lower than that of the control group, and significant differences were also detected among the 3 POP groups. In this study, we found that the TGF- beta 1 and CTGF protein expression may be associated with POP, especially in POP-Q stages