Objective To observe the influence of the transforming growth factor β1(TGF-β1) on the denervated mouse musclederived stem cells(MDSCs) producing the connective tissue growth factor(CTGF)at different time points in vitro. Methods MDSCs from the primarycultureof the denervated mouse skeletal muscle were isolated and purified by the preplate technique, and they were identified before the culture and after the culturein vitro with TGF-β1 (10 ng/ml) for 24 hours. Then, MDSCs were randomlydivided into 6 groups (Groups A, B, C, D, E and F) according to the different time points, and were cultured in vitro with TGF-β1 (10 ng/ml) for 0, 3, 6, 12, 24 and 48 hours, respectively. The levels of CTGF mRNA in MDSCs were measured by the real time RT-PCR and the expression of CTGF protein was detected by the CTGF Western blot. Results The immunohistochemistry revealed that before the adding of TGF-β1, MDSCs highly expressed Sca-1, with a positivityrate of 96%; however, after the adding of TGF-β1, the positive expression of Sca-1 decreased greatly, with a negativity rate gt;99%. The Western blot test showed that the ratios of CTGF to the average absorbance of βactin in Groups A-F were 0.788±0.123, 1.063±0.143, 2.154±0.153, 2.997±0.136, 3.796±0.153 and 3.802±0.175, respectively. In Groups AD,the absorbance increased gradually, with a significant difference between the abovementioned groups (Plt;0.05). However, in Groups D-F, there was no significant difference between the groups as the promotive tendency became less significant (P>0.05). The RT-PCR test showed that the △Ct values in GroupsA-F were 1.659±0.215, 1.897±0.134, 2.188±0.259, 2.814±0.263,2.903±0.125 and 3.101±0.186, respectively. In Groups A-D, the increase in the △Ct value was gradual, but the differences were significant between the groups (Plt;0.05). But in Groups E and F, the promotive tendency became less significant(Pgt;0.05). Conclusion TGF-β1 can promote the production of CTGF inthe mouse MDSCs cultured in vitro and the time-dependent relation exists for 3-12 hours.
Objective To investigate the role and mechanism of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) in the activation of aortic valve interstitial cells (AVICs) in aortic stenosis. Methods Isolating primary AVICs and stimulating their activation with transforming growth factor β1 (TGF-β1, 30 ng/mL), the expression of PGC-1α was detected. The activation of AVICs induced by TGF-β1 was observed after overexpression of PGC-1α by adenovirus or inhibition of PGC-1α function by GW9662. The possible downstream molecular mechanism of PGC-1α in AVICs activation was screened. Finally, the phenotype was further verified in primary human AVICs. Results The expression of PGC-1α decreased after the activation of AVICs induced by TGF-β1 (control group: 1.00±0.18; 24 h: 0.31±0.10; 48 h: 0.32±0.06; 72 h: 0.20±0.07; P<0.05). Specific overexpression of PGC-1α by adenovirus inhibited the activation of AVICs induced by TGF-β1 stimulation (periostin: 3.17±0.64 vs. 1.45±0.54, P<0.05; α-smooth muscle actin: 0.77±0.11 vs. 0.28±0.06, P<0.05). On the contrary, inhibition of PGC-1α function by GW9662 promoted the activation of AVICs (periostin: 2.20±0.68 vs. 7.99±2.50, P<0.05). Subsequently, it was found that PGC-1α might inhibit the activation of AVICs through downregulating the expression of calcium/calmodulin-dependent protein kinase (CAMK1δ) (0.97±0.04 vs. 0.74±0.11, P<0.05), and downregulating the expression of CAMK1δ alleviated the activation of AVICs (periostin: 1.76±0.11 vs. 0.99±0.20, P<0.05). The possible mechanism was that the activation of mammalian target of rapamycin (mTOR) signaling pathway was inhibited by reducing the accumulation of reactive oxygen species (ROS) (778.3±139.4 vs. 159.3±43.2, P<0.05). Finally, the protective effect of PGC-1α overexpression was verified in the activated phenotype of human AVICs (periostin: 2.73±0.53 vs. 1.63±0.14, P<0.05; connective tissue growth factor: 1.27±0.04 vs. 0.48±0.09, P<0.05). Conclusions The expression of PGC-1α significantly decreases during the activation of AVICs induced by TGF-β1. The overexpression of PGC-1α significantly inhibites the activation of AVICs, suggesting that PGC-1α plays a protective role in the activation of AVICs. The possible mechanism is that PGC-1α can inhibit the activation of CAMK1δ-ROS-mTOR pathway. In conclusion, interventions based on PGC-1α expression levels are new potential therapeutic targets for aortic stenosis.
ObjectiveTo improve the knowledge of a rare disease named pyridoxine-dependent epilepsy.MethodsHigh-throughput sequencing and Sanger sequencing were used to validate the genes of epilepsy. Mutation gene validation was performed on two probands and their parents. Analyze clinical manifestations, electroencephalogram (EEG), imaging and prognostic features of the two probands.ResultsProbands 1, seizure onset at 4 months, progress as drug-refractory epilepsy, manifested as seizures types origin of multi-focal lesions. Head MRI and fluorodeoxyglucose-positron-based tomography (FDG-PET) were both normal. Gene detection showed that Aldehydedehydrogenase (ALDH7A1) gene has a complex heterozygous mutation contain c.1442G> and c.1046C> T.Proband 2, seizure onset at 5 months, manifested as a tonic-clonic seizure. Intermittent EEG and head MRI were both normal. Genotyping revealed ALDH7A1 gene contain a complex heterozygous mutation c.1547A> G and c.965C> T. Two cases were both seizure free by vitamin B6 therapy and gradually reduce the antiepileptic drugs.ConclusionsPyridoxine-dependent epilepsy may be late onset, some patient can be atypical and early experimental treatment can help to identify and the diagnosis should be confirmed by gene test.
ObjectiveTo review the recent progress in the role of thrombospondins (TSPs) in synapse formation in the central nervous system (CNS).MethodsA wide range of domestic and foreign literature on the role of TSPs in the synapse formation of the CNS was reviewed. The role of TSPs in structural features, molecules, and related diseases was reviewed.ResultsAs an oligosaccharide protein, TSPs play important roles in angiogenesis, inflammation, osteogenesis, cell proliferation, and apoptosis. In the nervous system, they bind to voltage-dependent calcium channels, neuronectin, and other extracellular matrix proteins and cell surface receptors, and participate in and regulate multiple processes such as synapse formation, maturation, and function in the CNS.ConclusionTSPs as an oligomeric extracellular matrix protein play an important role in the formation of synapses and the repair of synapses after CNS injury.
Objective To observe macular vascular density and structural characteristics in children with transfusion-dependent β-thalassemia (TDT). MethodsA retrospective clinical study. From October 2022 to December 2023, 29 TDT children (58 eyes) diagnosed and examined at the Department of Hematology, Affiliated Hospital of Guangdong Medical University were included in the TDT group, along with 29 age- and gender-matched healthy children (58 eyes) as the control group. All participants underwent optical coherence tomography and angiography. Measurements included central macular thickness (CMT), subretinal choroidal thickness (SFCT), choroidal thickness (ChT), choroidal vascularity index, blood flow density in the superficial capillary plexus (SCP), deep capillary plexus (DCP), choriocapillaris layer (CC), and choroidal layer of the macular region, as well as the foveal avascular zone (FAZ) area of the SCP and DCP. A generalized estimating equation was used to compare differences in the above parameters between the two groups. Pearson correlation analysis was employed to examine the relationships between fundus structural parameters, blood flow density, and blood indices. ResultsCompared with the control group, the TDT group showed significantly thinner CMT (χ2=6.044) and ChT at 3.0 mm nasal (χ2=4.451) and temporal (χ2=4.767) to the fovea (P<0.05). The TDT group also demonstrated reduced blood flow density in the inferior DCP (χ2=5.254), whole CC (χ2=3.996), and superior CC (χ2=5.094), as well as enlarged FAZ area in DCP (χ2=4.286) (P<0.05). Correlation analysis revealed a negative correlation between SFCT and disease duration (r=−0.357, P=0.006). ConclusionsIn children with TDT, CMT and ChT become thinner and the area of FAZ expands. The blood flow densities of DCP and CC in the macular area decreased.
Objective To explore the role and clinical significance of cell-cycle dependent kinase 1 (CDK1) and its upstream and downstream molecules in the development of malignant peripheral nerve sheath tumor (MPNST) through the analysis of clinical tissue samples. Methods A total of 56 tumor samples from MPNST patients (“Tianjin” dataset) who underwent surgical resection, confirmed by histology and pathology between September 2011 and March 2020, along with 17 normal tissue samples, were selected as the research subjects. MPNST-related hub genes were identified through transcriptome sequencing, bioinformatics analysis, immunohistochemistry staining, and survival analysis, and their expression levels and prognostic associations were analyzed. Results Transcriptome sequencing and bioinformatics analysis revealed that upregulated genes in MPNST were predominantly enriched in cell cycle-related pathways, with CDK1 occupying a central position among all differentially expressed genes. Further differential analysis demonstrated that CDK1 mRNA expression in sarcoma tissues was significantly higher than in normal tissues [based on searching the cancer genome atlas (TCGA) dataset, P<0.05]. In MPNST tissues, CDK1 mRNA expression was not only significantly higher than in normal tissues (based on Tianjin, GSE141438 datasets, P<0.05), but also significantly higher than in neurofibromatosis (NF) and plexiform neurofibromas (PNF) (based on GSE66743 and GSE145064 datasets, P<0.05). Immunohistochemical staining results indicated that the expression rate of CDK1 protein in MPNST tissues was 40.31%. Survival analysis results demonstrated that CDK1 expression was associated with poor prognosis. The survival time of MPNST patients with high CDK1 mRNA expression was significantly lower than that of the low expression group (P<0.05), and the overall survival trend of patients with positive CDK1 protein expression was worse than that of patients with negative CDK1 expression. Additionally, differential analysis of CDK family genes (CDK1-8) revealed that only CDK1 was significantly upregulated in MPNST, NF, and PNF. Conclusion Increased expression of CDK1 is associated with poor prognosis in MPNST patients. Compared to other CDK family members, CDK1 exhibits a unique expression pattern, suggesting its potential as a therapeutic target for MPNST.
OBJECTIVE: To explore the mechanism of microvascular spasm after limb ischemia-reperfusion. METHODS: The rabbit hindlimb normothermic tourniquet ischemia model was employed. The tendon on the dorsum of the foot was exposed for observation of microvessels. The responses of arterioles on tendon surface to topical application of 10(-6) mol/L noradrenaline (NE) (a vasoconstrictor), 10(-6) mol/l acetylcholine(Ach) (an endothelium-dependent vasodilator) and 10(-4) mol/L nitroglycerin(NTG) (an endothelium-independent vasodilator) were observed at the period of ischemia and following 30 minutes of reperfusion after 2 hours and 5 hours of ischemia by use of intravital microscopy. RESULTS: No significant changes in the responses of arterioles to NE, Ach and NTG were noted following 30 minutes of reperfusion after 2 hours of ischemia compared with pre-ischemia. The constrictor responses of arterioles to NE were still not significantly altered following 30 minutes of reperfusion after 5 hours of ischemia, however, the dilation responses to Ach and NTG were significantly decreased (to Ach P lt; 0.01; to NTG, P lt; 0.05). CONCLUSION: Reperfusion after 5 hours of ischemia significantly impairs both the endothelium-dependent and endothelium-independent vasodilation, meanwhile preserves constrictor responses to NE, these may contribute to the genesis of the vasospasm in ischemia reperfusion.
Abstract:Objective To observe the expression of calcium-dependent proline-rich tyrosine kinase-2(Pyk2) in myocardium of rheumatic heart disease, the relationship between its role and cardiac fibrosis and clinical significance. Methods The blue myocardium collagen stain were analysed after Masson staining in 30 patients with rheumatic heart disease (RHD group) and 6 normal myocardium specimens (control group). The contents of hyaluronic acid (HA), laminin(LN) and type IV collagen(IV-C) were detected by radio-immunity method,and the expressions of Pyk2 protein and messenger ribonucleic acid(mRNA) were explored by immunohistochemistry methods and reverse transcriptase polymerase chain reaction (RT PCR),then the correlations of these results were statistically analyzed. Results The contents of HA,LN and IV C in RHDgroup increased compared to control group(174.95±76.14μg/L vs. 70.06±15.63μg/L, 153. 86 ± 20. 72μg/L vs. 90.01±14. 11μg/L, 95. 26±7.66μg/L vs. 63. 21±10.62μg/L; P= 0.003, 0. 013, 0. 035). The Pyk2 absorption and the ratio of Pyk2 mRNA/glyceraldehyde phosphate dehydrogenase (GAPDH) in RHD group were significantly higher than those in control group (0. 325 ± 0. 032 vs. 0.106±0.013, 0.870±0.085 vs. 0.573±0.042; P=0.048, 0.006).There were positive correlativity between the expression of Pyk2 protein and HA, LN and IV-C (r=0. 611, 0. 743, 0. 829, P〈0. 01), there were positive correlativity between the expression of Pyk2 mRNA and LN, IV-C (r=0. 794, 0. 766, P〈0.05). Conclusion Pyk2 may play a key role in the proceeding of cardiac fibrosis in rheumatic heart disease by increasing collagen synthesis in myocardium.
Objective To investigate the effect of the synthetic bone morphogenetic protein 2 (BMP-2)derived peptide on the osteogenic induction in the marrow mesenchymal stem cells (MSCs)and to evaluate the osteoinductivity and dosedependence of the BMP-2 derived peptide in vitro. Methods MSCs of 4-week old Wistar rats were separated and cultured. In the 3rd passage, the conditional culture medium was changed, in which the BMP-2-derived peptide in the following doses was added: 300,200, 100, 50, and 0 μg/ml, respectively (Groups A-E). The activity of alkaline phosphatase (ALP)and the amount of calciumdeposition were meassured at 5,10,15 and 20 days during the culture with the conditional culture medium. The real-time fluorescent quantitative polymerase chain reaction (FQ-PCR) was performed to measure the mRNA expressions of collagen type Ⅰ, osteopontin (OPN), and osteocalcin(OCN)and to measure the osteoinductivity of the BMP-2-derived peptide in the different concentrations.Results Under the inverted phase contrast microscope, MSCs cultured in the conditional culture medium for 3-4 days were changed in shape, from long fusiform to short fusiform or polygon. As the concentration of the BMP-2-derived peptide increased, the time for MSCs to change into the osteoblasts decreased. There was a significantly greater level of the ALP activity and amount of the calcium deposition in Groups A and B than in the other groups(Plt;0.05). However,there was no significant difference between Group A and Group B (Pgt;0.05). Theresult of FQPCR showed that after MSCs were cultured in the different doses of theconditional culture medium for 14 days, the mRNA expressions of collagen type Ⅰ, OPN andOCN were at higher levels. An increasing order in the level of the cycle threshold (Ct) was found in the following groups: Agt;Bgt;Cgt;D. Almost no expression was found in Group E. The Ct levels were significantly greater in Groups A and B thanin Groups C and D(Plt;0.05). However, there was no significant difference between Group A and Group B (Pgt;0.05).ConclusionThe BMP-2-derived peptide can greatly promote differentiation of MSCs into the osteoblasts, the promotion of osteogenesis has a dosedependent pattern, and the best inducing dosage is 200 μg/ml.