Indolepropionic acid inhibition of microglial cell M1 polarization for treatment of spinal cord injury / 中国组织工程研究

BACKGROUND:Indolepropionic acid has been shown to reduce diabetes-induced central nervous system inflammation.However,there is a lack of research on whether to inhibit microglia M1 polarization for the treatment of spinal cord injury. OBJECTIVE:To investigate the mechanism of indolepropionic acid inhibition of microglial cell M1 polarization for the treatment of spinal cord injury through cell and animal experiments. METHODS:(1)In vitro experiments:BV2 cell viability was assessed using the CCK-8 assay to determine optimal concentrations of indolepropionic acid.Subsequently,BV2 cells were categorized into control group,administration group(50 μmol/L indolepropionic acid),lipopolysaccharide group(100 ng/mL lipopolysaccharide),and treatment group(100 ng/mL lipopolysaccharide + 50 μmol/L indolepropionic acid).Nitric oxide content was quantified using the Griess method.Real-time quantitative PCR and western blot assay were employed to measure mRNA and protein levels of pro-inflammatory factors.Cell immunofluorescence staining was conducted to assess inducible nitric oxide synthase expression.The Seahorse assay was employed to assess glycolytic stress levels in BV2 cells.(2)In vivo experiments:30 SD rats were randomly divided into three groups:sham surgery group,spinal cord injury group,and indolepropionic acid group.Motor function recovery in rats after spinal cord injury was assessed using BBB scoring and the inclined plane test.Immunofluorescence staining of spinal cord tissue was conducted to evaluate the expression of inducible nitric oxide synthase in microglial cells.ELISA was employed to measure protein expression levels of the pro-inflammatory cytokines interleukin-1β and tumor necrosis factor-α in spinal cord tissue. RESULTS AND CONCLUSION:(1)In vitro experiments:Indolepropionic acid exhibited significant suppression of BV2 cell viability when its concentration exceeded 50 μmol/L.Indolepropionic acid achieved this by inhibiting the activation of the nuclear factor κB signaling pathway,thereby suppressing the mRNA and protein expression levels of pro-inflammatory cytokines(interleukin-1β and tumor necrosis factor-α),as well as the M1 polarization marker,inducible nitric oxide synthase,in BV2 cells.Additionally,indolepropionic acid notably reduced the glycolytic level in BV2 cells induced by lipopolysaccharides.(2)In vivo experiments:Following indolepropionic acid intervention in spinal cord injury rats,there was a noticeable increase in BBB scores and the inclined plane test angle.There was also a significant decrease in the number of M1-polarized microglial cells in spinal cord tissue,accompanied by a marked reduction in the protein expression levels of pro-inflammatory cytokines(interleukin-1β and tumor necrosis factor-α).(3)These results conclude that indolepropionic acid promotes functional recovery after spinal cord injury by improving the inflammatory microenvironment through inhibition of microglia M1 polarization.

Short-chain fatty acids ameliorate spinal cord injury recovery by regulating the balance of regulatory T cells and effector IL-17+ γδ T cells / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Spinal cord injury (SCI) causes motor, sensory, and autonomic dysfunctions. The gut microbiome has an important role in SCI, while short-chain fatty acids (SCFAs) are one of the main bioactive mediators of microbiota. In the present study, we explored the effects of oral administration of exogenous SCFAs on the recovery of locomotor function and tissue repair in SCI. Allen's method was utilized to establish an SCI model in Sprague-Dawley (SD) rats. The animals received water containing a mixture of 150 mmol/L SCFAs after SCI. After 21 d of treatment, the Basso, Beattie, and Bresnahan (BBB) score increased, the regularity index improved, and the base of support (BOS) value declined. Spinal cord tissue inflammatory infiltration was alleviated, the spinal cord necrosis cavity was reduced, and the numbers of motor neurons and Nissl bodies were elevated. Enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction (qPCR), and immunohistochemistry assay revealed that the expression of interleukin (IL)‍-10 increased and that of IL-17 decreased in the spinal cord. SCFAs promoted gut homeostasis, induced intestinal T cells to shift toward an anti-inflammatory phenotype, and promoted regulatory T (Treg) cells to secrete IL-10, affecting Treg cells and IL-17+ γδ T cells in the spinal cord. Furthermore, we observed that Treg cells migrated from the gut to the spinal cord region after SCI. The above findings confirm that SCFAs can regulate Treg cells in the gut and affect the balance of Treg and IL-17+ γδ T cells in the spinal cord, which inhibits the inflammatory response and promotes the motor function in SCI rats. Our findings suggest that there is a relationship among gut, spinal cord, and immune cells, and the "gut-spinal cord-immune" axis may be one of the mechanisms regulating neural repair after SCI.

Effect of miRNA-136-5p on inflammatory factors in rat models of acute spinal cord injury / 中国组织工程研究

BACKGROUND: miRNA-136-5 p plays a crucial regulatory role in pathological changes, inflammatory response and regeneration after spinal cord injury. OBJECTIVE: To investigate the effect of miRNA-136-5 p on the expression of cytokines in serum and NF-κB protein in spinal cord in rats with spinal cord injury and to explore the molecular mechanism. METHODS: Thirty-six male Sprague-Dawley rats, of SPF grade were provided by Laboratory Animal Center of Guangxi Medical University. The lentiviral vector system was prepared and transfected into spinal cord injured rats. Thirty-six rat models of spinal cord injury were established by modified Allen's method. Basso Beattie Bresnahan scores were performed. Rats were randomly divided into normal control, modeling (LV-ctrl plus spinal cord injury), overexpression (spinal cord injury plus LV-miRNA-136-5 p), and inhibition (spinal cord injury plus LV-sponge) groups (n=9/group). Seven days before surgery and the day of surgery, the overexpression and inhibition groups were continuously injected with the lentivirus suspension into the injured area, and the normal control and modeling groups were injected with the same amount of normal saline. Three rats were sacrificed at 1, 3 and 7 days, and blood and spinal cord tissues were taken. The levels of interleukin-1β, interleukion-6 and interferon-α in rat serum were determined by ELISA. The expression of NF-κB protein was detected by western blot assay and double immunofluorescence. RESULTS AND CONCLUSION: (1) There was no significant difference in preoperative Basso Beattie Bresnahan scores (P＞ 0.05). In the modeling group, the rats showed prone walking, vary degrees of urinary retention, and spinal shock, with complete loss of function of both hind limbs and muscle strength of 0. (2) Compared with the normal control group, the levels of inflammatory factors in the other groups were increased significantly (P ＜ 0.05). The expression levels of inflammatory factors were highest in the overexpression group, followed by modeling group, and lowest in the inhibition group. (3) Results of western blot assay and double immunofluorescence showed that the expression level of NF-κB protein in the modeling, overexpression and inhibition groups was significantly higher than that in the normal control group (P ＜ 0.05), and the level was highest in the overexpression group. (4) In summary, miRNA-136-5 p can affect inflammatory factors and NF-κB in rats with acute spinal cord injury.

Changes of cytokines in peripheral blood within 48 hours after acute spinal cord injury / 中国组织工程研究

BACKGROUND: Change of microenvironment after acute spinal cord injury is the main factor causing secondary injury, so it is of great significance to investigate the changes of microenvironment after acute spinal cord injury for clinical diagnosis and treatment. OBJECTIVE: To investigate the expression levels and clinical significance of interleukin-6, brain derived neurotrophic factor, basic fibroblast growth factor, neurotrophin-3 and neurotrophin-4 in peripheral blood within 48 hours after acute spinal cord injury. METHODS: Twenty-nine patients with acute spinal cord injury admitted at the Department of Spinal Osteopathia, the First Affiliated Hospital of Guangxi Medical University from October 2016 to June 2018 were enrolled, and were divided into two groups according to American Spinal Injury Association impairment scale: complete spinal cord injury (n=11) and incomplete spinal cord injury (n=18). Thirteen patients with avascular necrosis of the femoral head were selected as controls. The expression levels of interleukin-6, brain derived neurotrophic factor, basic fibroblast growth factor, neurotrophin-3 and neurotrophin-4 in peripheral blood of 42 patients were determined by ELISA and compared. RESULTS AND CONCLUSION: The ELISA results showed that the expression levels of interleukin-6, brain derived neurotrophic factor, basic fibroblast growth factor, neurotrophin-3 and neurotrophin-4 in peripheral blood in the spinal cord injury group were significantly higher than those in the control group (P ＜ 0.05). The expression levels of all above cytokines in the complete spinal cord injury group were significantly higher than those in the incomplete spinal cord injury group (P ＜ 0.05). In summary, increased expression of interleukin-6, brain derived neurotrophic factor, basic fibroblast growth factor, neurotrophin-3, neurotrophin-4 after acute spinal cord injury indicates that it may participate in the important pathophysiological process after acute spinal cord injury.

Risk factors for early death in acute myocardial infarction patients complicating with ventricular septal rupture / 中华心血管病杂志

Objective@#To assess the clinical characteristics and identify the risk factors in the acute myocardial infarction (AMI) patients complicating with ventricular septal rupture (VSR).@*Methods@#A retrospective study was performed on 96 AMI patients complicating with VSR, who were hospitalized in the Second Xiangya Hospital of Central South University, Hunan Provincial Peoples′ Hospital, the First Affiliated Hospital of University of South China, the Second Affiliated hospital of University of south China, Xiangtan Central Hospital from December 2007 to May 2017. There were 46 females and the age was (66.2±10.7) years (from 43 to 90 years). Patients were divided into in-hospital survival group (n=64) and in-hospital death group (n=32). The 96 patients were also divided into the early death group (survived ≤2 weeks after admission, n=50) and non-early death group (survived>2 weeks after admission, n=46). Multivariate logistic regression was used to analyze the independent risk factors of the early death.@*Results@#Location of VSR was available in 71 patients, VSR was located at the apical or anterior septum near the apical region in 64.0% (32/50) patients with the anterior AMI, VSR was located at the posterior wall and basal inferior segment in 57.1% (12/21) patients with non-anterior AMI. Compared to the in-hospital survival group, patients in the in-hospital death group were older ((69.6±11.3) years vs. (64.6±10.1) years, P=0.031), incidence of non-ventricular aneurysm (71.9% (23/32) vs. 37.5% (24/64), P=0.001) and anterior AMI (84.4%(27/32) vs. 62.5%(40/64), P=0.028) was significantly higher in the in-hospital death group than in the in-hospital survival group. The comparison between the early death group and non-early death group showed that older age, female, no history of angina or myocardial infarction, Killip grade>Ⅲ, and non-ventricular aneurysm were related to increased risk of the early mortality in this patient cohort. Logistic regression analysis revealed that female (OR=5.109,95%CI 1.19-22.00, P=0.012), no history of angina or myocardial infarction (OR=23.34, 95%CI 3.44-158.37, P=0.001), Killip grade>Ⅲ(OR=5.35, 95%CI 1.26-22.66, P=0.019) and non-ventricular aneurysm (OR=6.30,95%CI 1.67-23.73, P=0.005) were independent risk factors for early death in this patient cohort.@*Conclusion@#The risk factors of in-hospital death include older age, non-ventricular aneurysm and anterior AMI. Female, no history of angina or myocardial infarction, Killip grade>Ⅲ and non-ventricular aneurysm are independent risk factors for the early death of AMI patients complicating VSR.

Polygonatum sibiricum polysaccharide promotes osteogenesis by signaling pathway activation after LRP5 silencing / 中国组织工程研究

BACKGROUND:Our previous studies have found that polygonatum sibiricum polysaccharide (PSP) promotes osteogenic differentiation of bone marrow mesenchymal stem cel s (BMSCs) by Wnt/β-catenin signaling pathway, but the molecular mechanism is unclear.OBJECTIVE:To investigate the effect of PSP promoting the osteogenic differentiation via Wnt signaling pathways in BMSCs after LRP5 silencing. METHODS:LRP5 interference vectors were constructed and then transfected into C57BL/6 mouse BMSCs cultured in vitro. The transfection efficiency of cel s was calculated under fluorescence inverted microscope and the expression of LRP5 protein was detected by western blot assay. The osteogenic potential of BMSCs after LRP5-siRNA transfection was analyzed by alkaline phosphatase staining, alizarin red staining and western blot assay. Effect of PSP on the osteogenic differentiation of LIRP5-silenced mouse BMSCs was detected by real-time PCR and dual luciferase assay. RESULTS AND CONCLUSION:Compared with the control group, the mineralization ability, the mRNA expressions of Runx2 and Osterix, and the protein expression of LRP5 were significantly decreased in the LRP5-siRNA group (P<0.05). PSP could promote LRP5-siRNA transfected mouse BMSCs differentiating into osteoblasts and significantly upregulated the expressions ofβ-catenin and Osterixin, and also induced the high expression of luciferase reporter gene (TOPFlash) containing wild type TCF binding sites (P<0.05). To conclude, LRP5 plays an important role in the process of mouse BMSCs differentiating into osteoblasts. PSP can promote the osteogenic differentiation of mouse BMSCs by activating the Wnt/β-catenin signaling pathway independent on LRP5.

The effect of Polygonatum Sibiricum Polysaccharide on the expression of OPG and RANKL in the rat model of ovariectomy-induced osteoporosis / 实用医学杂志

Objective To investigate PSP on bone microstructures,Ca,P,OPG and RANKL of osteoporotic rat model.Methods Thirty female rats randomly divided into five groups:Sham,OVX,H-,M-,L-PSP.Sham and OVX were irrigated stomachsaline;PSP solution was gavaged to other groups.After 8-week,bone microstructures of tibial metaphyseal,Ca,P,OPG and RANKL were measured.Results Body weight,Ca,P,RANKL,Tb.Sp of OVX were significantly increased compared to Sham,OPG,BV/TV,Tb.Th,Tb.N decreased.Body weight of H-,M-PSP,Ca and Tb.Sp of PSP,P and RANKL in H-PSP were decreased compared to OVX,OPG in H-,M-PSP,BV/TV,Tb.Th,Tb.N of PSP group increased.The differences were statistically significant (P ＜ 0.05).Conclusion PSP prevents osteoporosis by improving the microstructure of trabecular bone,reducing bone turnover,increasing OPG and reducing RANKL expression.

Polygonatum sibiricum polysaccharide attenuates bone marrow-derived macrophages to differentiate into osteoclasts and protects against lipopolysaccharide-induced osteolysis in vivo / 中国组织工程研究

BACKGROUND: Bone marrow-derived mononuclear cells (BM-MNCs) hold the potential of differentiating into osteoclasts. Polygonatum sibiricum polysaccharide (PSP) may inhibit the differentiation of BM-MNCs into osteoclasts and it is expected to become a new drug for the treatment of osteoporosis. OBJECTIVE: To investigate the effect of PSP on the differentiation of mouse BM-MNCs into osteoclasts induced by receptor activator of nuclear factor kappa-B ligand (RANKL) and bone resorption in vivo. METHODS: Mouse bone marrow-derived macrophages cultured in vitro, the effect of macrophage colony stimulating factor and PSP (5, 10, 20, 40, 80,160, 320, 640, 1280, 2560 mg/L) on the proliferation of mouse BM-MNCs was detected by cell counting kit-8 assay to determine the PSP concentration range; the mouse BMMs were cultured and induced in DMEM medium containing macrophage colony stimulating factor, RANKL and 5, 10, 20, 40, 80,160, 320, 640 mg/L PSP, respectively; those cultured without PSP served as control group. The morphological changes of cells were observed under an inverted microscope.; the number of osteoclasts was detected by tartrate-resistant acid phosphatase staining; the mRNA expression levels of osteoclast-related genes including tartrate-resistant acid phosphatase, matrix metalloproteinase-9, cathepsin K, and nuclear factor of activated T cells c1 were evaluated by quantitative real-time PCR. A mouse model of calvarial osteolysis induced by lipopolysaccharide was established to receive PSP intervention, and then micro CT scanning, three-dimensional reconstruction and relevants software were used for quantitative analysis of bone volume/volume percentage, trabecular number, trabecular bone spacing and thickness. The number of osteoclasts was identified by tartrate-resistant acid phosphatase staining and quantitative analysis of bone resorption area was conducted. RESULTS AND CONCLUSION: Compared with the control group, the concentration of PSP below 640 mg/L showed no significant effect on the proliferation of BMMs (P > 0.05). Different concentrations of PSP (40-640 mg/L) significantly reduced the number of osteoclasts, osteoclast differentiation and maturation, and the mRNA expression levels of tartrate-resistant acid phosphatase, matrix metalloproteinase-9, cathepsin K, and nuclear factor of activated T cells c1 TRAP, MMP-9, CtsK and NFATc1 (P < 0.05). Compared with lipopolysaccharide, PSP could effectively alleviate the lipopolysaccharide-induced calvarial osteolysis, and the bone volume/volume percentage, trabecular number, and trabecular bone spacing were significantly decreased (P < 0.05); additionally, the number of osteoclasts and the area of bone resorption were decreased significantly (P < 0.01). To conclude, PSP can inhibit the differentiation and maturation of mouse BMMs to osteoclasts and alleviate lipopolysaccharide-induced calvarial osteolysis.

Polygonatum sibiricum polysaccharide regulates osteoblastic differentiation of mouse bone marrow-derived mesenchymal stem cells / 中国组织工程研究

BACKGROUND:Bone marrow mesenchymal stem cels (BMSCs) have the ability of multi-directional differentiation. Polygonatum sibiricum polysaccharide can promote osteogenetic differentiation of mouse BMSCs by activating Wnt/β-catenin signaling pathway, which is expected to become a new drug for the treatment of osteoporosis. OBJECTIVE:To investigate the effects of Polygonatum sibiricum polysaccharide on Wnt/β-catenin signaling pathway in the osteogenic differentiation of mouse BMSCs. METHODS:The mouse BMSCs were cultured and induced in osteoblast medium containing final concentrations (5, 10, 25, 50mg/L) of Polygonatum sibiricum polysaccharide. The mouse BMSCs treated without Polygonatum sibiricum polysaccharide was set as the negative control group. The morphological changes of cels were observed under an inverted microscope. Alkaline phosphatase (ALP) activity assay was performed by PNPP method. The mineralization nodules were observed and stained with alizarin red S and the number and area fraction were recorded under an inverted microscope. The mRNA expressions of osteogenesis-related genes ALP, Runx2, and osteocalcin were evaluated by quantitative real-time PCR (qRT-PCR). qRT-PCR and western blot were used to determine the expression level of β-catenin. The downstream β-catenin/TCF transcriptional activity was evaluated with the Dual-Luciferase Reporter Assay System. RESULTS AND CONCLUSION: Compared with the control group, polygonatum sibiricum polysaccharide significantly enhanced the alkaline phosphatase activity, the mineralization ability of cels, and the mRNA expression of ALP, Runx2 and osteocalcin in the differentiated BMSCs in a dose dependent manner (P <0.05). After induction, the mRNA expression of β-catenin was the highest on the 3rd day. Polygonatum sibiricum polysaccharide significantly increased the expression of β-catenin (P < 0.05) in the process of promoting the differentiation of BMSCs into osteoblasts, and also promoted the high-level expression of luciferase reporter gene (TOPFlash) which contains wild type TCF binding sites (P < 0.05). These results demonstrate that Polygonatum sibiricum polysaccharide can promote the osteoblast differentiation of mouse BMSCs by activating the Wnt/β-catenin signaling pathway.

Role of SREBP1 in atorvastatin-induced reduction of NLRP1 inflammasome ex-pression / 中国免疫学杂志

Objective:To investigate the role of sterol regulatory element binding protein-1 (SREBP1) in atorvastatin-induced reduction of nucleotide-binding oligomerization domain-like receptor protein 1 ( NLRP1 ) inflammasome expression. Methods:THP-1 cells were treated with phorbol 12-myristate 13-acetate (160 nmol/L) for 12 h to be differentiated into macrophages. The medium was then replaced with serum-free medium containing lipopolysaccharide and ( or ) atorvastatin. The mRNA expression of NLRP1 and SREBP1 were detected by Real-time PCR. The protein expression of NLRP1 and SREBP1 were determined by Western blot. Furthermore, we observed the effect of SREBP1 siRNA on atorvastatin-induced reduction of NLRP1 expression. Results:Atorvastatin inhibited the mRNA and protein expression of NLRP1 and SREBP1 in the THP-1 macrophages. SREBP1 siRNA showed no significant difference on lowering NLRP1 expression when compared with atorvastatin. Treating cells with SREBP1 siRNA and atorvastatin at the same time resulted in more obvious reduction of NLRP1 expression than single use of SREBP1 siRNA or atorvastatin. Conclusion:Atorvastatin might exert anti-inflammatory effect by repressing NLRP1 expression through the SREBP1 path-way.

Efficacy and safety of implantable cardioverter defibrillator avoiding routine defibrillation threshold testing / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the efficacy and safety of implantable cardioverter defibrillator (ICD) and cardiac resynchronization therapy-defibrillators (CRT-D) avoiding defibrillation threshold (DFT) testing when treating ventricular tachycardia (VT) or ventricular fibrillation (VF).@*METHODS@#We analyzed a continuous database of the 21 patients who had avoided DFT during ICD implantation from Oct. 1999 to Aug. 2008. Follow-up data were completed and analyzed in the 21 patients with ICD implantation.@*RESULTS@#ICDs were implanted successfully in 17 patients with VT or VF, and CRT-D were implanted successfully in 4 myocardiopathy patients with severe heart failure who avoided DFT during ICD or CRT-D implantation. Eight patients accepted DFT 1 week later, VT or VF was not induced in 3 patients (37.5%). During the mean follow-up of 1 approximately 7 (4.2+/-1.9) years, malignant ventricular arrythmia was recorded in 16 patients. Among them, 89 episodes were successfully terminated by defbrillation (100%), 120 VT events were terminated by the first run of antitachycardia pacing (51.1%) and 22 by low energy cardioversion (59.2%). All patients took antiarrhycardia drugs after ICD or CRT-D implantation. No patient died from malignant ventricular arrythmia during the follow-up.@*CONCLUSION@#No application of routine DFT may avoid complications associated with DFT during ICD or CRT-D implantation. ICD or CRT-D implantation may effectively treat fatal ventricular tachyarrhythmias and prevent sudden cardiac death.

The Effects of Rosiglitazone on the Levels of Serum HbA1c, hsCRP and IL-6 in Patients With Insulin-Inadequately Controlled Type 2 Diabetes / 中国医师杂志

Objective To investigate the effects of rosiglitazone (RSG) on the levels of serum HbA1c, interleukin-6(IL-6) and high sensitive C-reactive protein (hsCRP) in type 2 diabetic patients who were inadequately controlled only with insulin therapy. Methods 40 patients with type 2 diabetes mellitus (T2DM), whose blood glucose was poorly controlled (HbA1c≥7 5%) after 4 weeks of standardized insulin therapy, were additionally given 4mg daily PSG. The levels of serum HbA1c, IL-6, hsCRP, total cholesterol (Tch), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c) and high-density lipoprotein cholesterol (HDL-c) were measured before and after 12 weeks treatment with RSG. hsCRP was measured by high-sensitivity immunoturbidimetric method, and IL-6 by enzyme-linked immunoadsorbent assay (ELISA). Results ⑴ RSG 4mg daily significantly improved glycemic control, treatment with RSG 4 mg plus insulin resulted in a mean 1 59% reduction of HbA1c from baseline (P