南方医科大学学报杂志最新文献

Objectives: To investigate the mechanism of PHPS1 for promoting apoptosis of oral squamous cell carcinoma cells and the role of AMPK in regulating tumor angiogenesis under hypoxic conditions.

Methods: Human oral squamous cell carcinoma Ca9-22 cells cultured in hypoxic conditions (1% O₂) were inoculated subcutaneously in 16 nude mice, which were divided into control group and PHPS1 group (n=8) for treatment with 10% DMSO and 10% PHPS1 respectively. Tumor growth in the mice was monitored till 14 days after the treatment, and the xenografts were examined pathologically using HE staining. In Ca9-22 cells cultured in 1% O₂, the effect of PHPS1, compound C (an AMPK inhibitor), and their combination on expressions of SHP-2, AMPK, HIF-1α, PD-L1, caspase-8, caspase-3 and BAX were evaluated using Western blotting.

Results: In the tumor-bearing nude mice, PHPS1 treatment significantly inhibited tumor growth and neovascularization. HE staining showed significantly reduced tumor angiogenesis in PHPS1-treated mice. In Ca9-22 cells in hypoxic cultures, PHPS1 treatment significantly decreased the expression levels of SHP-2, HIF-1α, PD-L1, ERK2, STAT3 and VEGF and increased the expression of AMPK. The inhibitory effects of PHPS1 on HIF-1α and PD-L1 were obviously attenuated by the addition of compound C. PHPS1 also enhanced the expressions of caspase-3, caspase-8 and Bax proteins and increased the phosphorylation levels of PD-L1 and S195 in Ca9-22 cells, and these effects were effectively attenuated by compound C.

Conclusions: PHPS1 can enhance PD-L1 serine phosphorylation by regulating SHP-2/AMPK activity to promote apoptosis of oral squamous cell carcinoma cells under hypoxic conditions.

Objectives: To investigate the correlation of serum levels of bridging integrating factor 1 (BIN1) with acute myocardial infarction (AMI) and Killip class of the patients.

Methods: We retrospectively collected the data from 94 patients with AMI and 30 healthy individuals for analysis of the correlations of serum BIN1 levels with Killip class, TIMI scores, and neutrophil-to-lymphocyte ratio (NLR). We also assessed the diagnostic value of BIN1 combined with NLR for AMI.

Results: Serum BIN1 levels were significantly lower in AMI patients than in the healthy individuals (P=0.032). The AMI patients with Killip class I had significantly lower serum BIN1 levels than the healthy individuals (P=0.008). Serum BIN1 level was an independent predictor of AMI with a predictive value of 0.630 (95% CI: 0.513-0.748) at the optimal cutoff level of 0.341 ng/mL, a specificity of 50%, and a sensitivity of 78.5%. Serum BIN1 level was also an independent predictor for Killip class I group in the AMI patients with a predictive value of 0.672 (95% CI: 0.548-0.797) at the optimal cutoff level of 0.287 ng/mL, a specificity of 74.1%, and a sensitivity of 60%. For AMI diagnosis, the combination of NLR and serum BIN1 level had a predictive value of 0.811 (95% CI: 0.727-0.895) at the optimal cutoff level of 0.548 ng/mL, with a specificity of 92.6% and a sensitivity of 62.2%. There was a positive correlation between serum BIN1 level and TIMI score in AMI patients (r=0.186, P=0.003).

Conclusions: BIN1 is correlated with AMI and can be helpful for predicting short-term prognosis of the patients, and BIN1 combined with NLR has a high diagnostic value for AMI.

Objectives: To investigate the risk factors of recurrence of acute ischemic stroke (AIS) within 1 year and establish a nomogram model for predicting the recurrence risk.

Methods: This study was conducted in two cohorts of AIS patients (≤7 days) hospitalized in Dongzhimen Hospital (modeling set) and Fangshan Hospital (validation set) from March, 2021 to March, 2022. Lasso regression analysis was used to identify the important predictive factors for AIS recurrence within 1 year, and multivariate Logistic regression analysis was performed to analyze the independent factors affecting AIS recurrence. The recurrence risk prediction nomogram model was constructed using R studio, and its discriminating power and calibration were assessed using ROC curve analysis and Hosmer-Lemeshow goodness-of-fit test.

Results: The modeling and validation sets contained 28 cases (15.22%) and 21 cases (15.00%) of AIS recurrence, respectively. In the modeling set, compared with the non-relapse group, the recurrence group had higher proportions of patients with age >65 years, diabetes, arrhythmia, constipation after stroke, and FBG >7.5 and significantly higher levels of NLR, UREA, Cr, HbA1c, FIB and TT (P<0.05). Multivariate Logistic regression analysis showed that an age >65 years, arrhythmia, constipation after stroke, FBG >7.5, NLR and Cr were all independent risk factors of AIS recurrence (P<0.05). Hosmer-Lemeshow goodness-of-fit test and calibration curve analysis showed that the risk prediction model had good fitting between the modeling set and the verification set. The ROC curve showed that for predicting AIS recurrence within 1 year, the AUC of the predictive model was 0.857 (95%CI: 0.782-0.932) in the modeling set and 0.679 (95%CI: 0.563-0.794) in the validation set.

Conclusions: The nomogram model established based on age >65 years, arrhythmia, constipation after stroke, FBG >7.5, NLR and Cr has a good predictive value for AIS recurrence within 1 year.

Objectives: To explore the neuroprotective mechanism of electroacupuncture at the acupoints Baihui and Shenting in rats with cerebral ischemia-reperfusion (IR) injury.

Methods: Forty-eight male SD rats were equally randomized into sham operation group, cerebral IR model group, acupoint electroacupuncture group and non-acupoint acupuncture group. In the latter 3 groups, cerebral focal ischemic injury was induced using the Longa method; in the two electroacupuncture groups, electroacupuncture was performed either at the acupoints Baihui and Shenting or at non-acupoint sites for 7 days. The changes in neurological deficit scores, cerebral infarction volume, learning and memory function, pathologies in hippocampal CA1 area, neuronal and synaptic ultrastructures, and synaptic density of the rats were observed, and serum GABA level and mRNA and protein expressions of GABA_AR α1, CaMK II, SYN1 and PSD-95 in the hippocampal tissue were detected.

Results: Compared with those in cerebral IR model group, the rats receiving electroacupuncture at the acupoints, but not those with electroacupuncture at the non-acupoints, showed significantly decreased neurological deficit scores and cerebral infarction volume with shortened escape latency and increased platform crossings. Electroacupuncture at the acupoints significantly increased neuronal cell number, decreased the width of the synaptic gaps and increased density of synaptic bodies in the ischemic hippocampal CA1 area, resulting also in increased serum GABA levels and hippocampal expressions of GABA_ARα1, SYN1 and PSD-95 and lowered expression level of CaMK II.

Conclusions: Electroacupuncture at Baihui and Shenting improves learning and memory function of rats with cerebral IR injury possibly through a mechanism that promotes synaptic regeneration, upregulates hippocampal expressions of GABAAR α 1, SYN1 and PSD-95 and downregulates the expression of CaMK II.

Objectives: To explore the mechanism of Qihuang Jianpi Zishen Granules (QJZG) for improving thrombocytopenia in a mouse model of systemic lupus erythematosus (SLE).

Methods: Twenty-four MRL/lpr lupus mice were randomized equally into 4 groups for treatment with daily gavage of saline, QJZG or prednisone (Pred) or intraperitoneal injection (twice a week) of CaMKK2 activator, with 6 C57BL/6 mice with saline gavage as the control group. After 8 weeks of treatment, the mice were examined for PLT, PCT, PDW, MPV, serum levels of TPO, IL-6, IL-10, TNF-α and IFN-γ, and calcium ion fluorescence intensity using ELISA or flow-through assay. RT-qPCR was used to detect platelet CaMKK2, AMPK2α, mTOR, Beclin1 and p62 mRNA expression levels, and the protein expressions of CaMKK2, p-CaMKK2, AMPK, p-AMPK, mTOR, p-mTOR, LC3, Beclin1 and p62 were detected using Western blotting.

Results: The saline-treated MRL/lpr lupus mice showed significantly lowered levels of PLT, PCT, IL-10, mTOR, p62 mRNA, p-mTOR and P62 with increased PDW, MPV, serum TPO, IL-6, TNF-α and IFN-γ levels, and platelet expressions of CaMKK2, AMPK, Bcl-1 mRNA, p-CaMKK2, p-AMPK, LC3II and Beclin1. These abnormalities were significantly improved in QJZG group and Pred group but worsened after treatment with the CaMKK2 activator.

Conclusions: QJZG can ameliorate thrombocytopenia in mouse models of SLE by reducing inflammation and inhibiting platelet autophagy via regulating the Ca²⁺/CaMKK2/AMPK/mTOR signaling pathways.

Objectives: To investigate the inhibitory effect of FER-1 on methylglyoxal-induced ferroptosis in cultured mouse alveolar macrophages.

Methods: MH-S cells derived from mouse alveolar macrophages treated with 90 μg/mL methylglyoxal, 10 μmol/mL FER-1MG+FER-1, or both were examined for intracellular reactive oxygen species (ROS), malondialdehyde (MDA) and ferrous ion (Fe²⁺) levels and changes in mitochondrial membrane potential. Western blotting was performed to detect the protein expression levels of glutathione peroxidase 4 (GPX4) and long-chain acyl-CoA synthase 4 (ACSL4).

Results: Methylglyoxal treatment of MH-S cells for 24 h significantly decreased the protein expression level of GPX4, upregulated the protein expression of ACSL4, increased intracellular concentrations of ferrous ions, ROS and MDA, caused loss of mitochondrial membrane potential, and decreased cell viability. Treatment of the cells with FER-1 effectively attenuated these detrimental effects of methylglyoxal in MH-S cells by increasing GPX4 expression, reducing ACSL4 expression and intracellular ferrous ions, ROS and MDA levels, and restoring the mitochondrial membrane potential.

Conclusions: Methylglyoxal can induce ferroptosis in MH-S cells in a dose-dependent manner, and FER-1 can rescue the cells from methylglyoxal-induced ferroptosis.

Objectives: To investigate the role of Holliday cross-recognition protein (HJURP) in tumorigenesis, progression, and immunotherapy responses.

Methods: Bioinformatics approaches were used to analyze the expression level of HJURP in various cancers and its association with prognosis, clinical stage, and immune cell infiltration using TCGA, GTEx, SangerBox and TIMER 2.0 databases. LinkedOmics database was employed to investigate HJURP-related genes and their potential functions in kidney renal clear cell carcinoma (KIRC). The expression of HJURP in KIRC samples was examined with immunohistochemistry, Western blotting and qRT-PCR, and the effect of HJURP silencing on cell proliferation and migration was tested in cultured KIRC cells.

Results: HJURP was highly expressed in 26 cancers with negative correlations with the patients' survival outcomes in 5 cancers including KIRC (P<0.05). HJURP expression levels was strongly correlated with clinical stages and immune cell infiltration in the tumors. In KIRC, HJURP expression was significantly elevated (P<0.0001) and showed a positive correlation with TNM stage (P<0.05), overall stage (P<0.01) and immune cell infiltration. Gene Ontology (GO) functional analysis showed that HJURP is predominantly enriched in biological processes such as biological regulation and metabolic processes. Concerning cellular components, HJURP is primarily localized to the cell membrane and nucleus. In terms of molecular functions, it is chiefly enriched in activities related to protein binding and ion binding. HJURP was highly expressed in both clinical KIRC tissues and KIRC cell lines (P<0.001). In cultured KIRC cells, silencing of HJURP significantly inhibited cell proliferation and migration abilities.

Conclusions: HJURP may serves as an indicator of prognosis and immunotherapy response of KIRC, and its high expression enhances malignant behaviors of KIRC cells.

OBJECTIVE: To assess the validity and effectiveness of parameter estimation using a time-dependent Weibull proportional hazards model for survival analysis containing partly interval censored data and explore the impact of different covariates on the results of analysis. METHODS: We established a time-dependent Weibull proportional hazards model using the Weibull distribution as the baseline hazard function of the model which incorporated time-varying covariates. Maximum likelihood estimation was employed to estimate the model parameters, which were obtained by optimization of the likelihood function. RESULTS AND CONCLUSION: Numerical simulation results showed that with higher proportions of precise observations across different sample sizes and parameter settings, the proposed model resulted in improved accuracy of parameter estimation with coverage probabilities approximating the theoretical expectation of 95%. As the sample sizes increased, the parameter biases of the model tended to decrease. Experiments with empirical data further validated the effectiveness of the model. Compared with the failure time data for each precisely observed individual, additional interval-censored data helped to obtain more effective estimates of the regression parameters. Comparison with the Cox model that included time-varying covariates further demonstrated the effectiveness of the time-dependent Weibull proportional hazards model for parameter estimation in survival analysis with partly interval censored data.

Objectives: To investigate the role of mitochondrial autophagy disorder caused by deletion of E3 ubiquitin ligase Parkin in neuroinflammation in a mouse model of MPTP-induced Parkinson's disease (PD).

Methods: Wild-type (WT) male C57BL/6 mice and Parkin^-/- mice were given intraperitoneal injections with MPTP or PBS for 5 consecutive days, and the changes in motor behaviors of the mice were observed using open field test. The effects of Parkin deletion on PD development and neuroinflammation were evaluated using immunofluorescence and Western blotting. The changes of the PINK 1/Parkin signaling pathway in the midbrain substantia nigra of the mice were examined to explore the molecular mechanism of Parkin-mediated regulation of mitochondrial autophagy and its effect on neuroinflammation in PD mice.

Results: Compared with their WT counterparts, the Parkin^-/- mice with MPTP injections exhibited significant impairment of motor function with decreased TH⁺ neurons, increased α-synuclein (α-syn) accumulation, and increased numbers of GFAP⁺ and I-ba1⁺ cells in the midbrain substantia nigra. Parkin deletion obviously affected PINK1/Parkin-mediated mitochondrial autophagy to result in significantly increased mtDNA and upregulated expressions of STING and NLRP3 inflammatosomes in the midbrain substantia nigra of MPTP-treated transgenic mice.

Conclusions: Parkin deletion causes mitochondrial autophagy disorder to accelerate PD progression and exacerbates neuroinflammation in mice by affecting the PINK1/Parkin signaling pathway, suggesting the important role of Parkin in early pathogenesis of PD.

Objectives: To explore the role of the cGAS-STING signaling pathway in the therapeutic mechanism of Liangxue Jiedu Huayu Formula (LXJDHYF) for acute-on-chronic liver failure (ACLF) in mice.

Methods: Thirty C57BL/6 mice were randomly divided into blank control group, model group, low- and high-dose LXJDHYF groups, and H151 (a specific cGAS-STING pathway inhibitor) group (n=6). In all but the control group, the mice were treated with CCl₄ to induce liver cirrhosis followed by intraperitoneal injections of lipopolysaccharide and D-amino galactose to establish mouse models of ACLF. After the treatments, the mouse livers were collected for HE and TUNEL staining, and serum levels of ALT, AST and TBil were determined. In bone marrow-derived macrophages (BMDMs) and liver tissues of ACLF mice, the expressions of cGAS-STING signaling pathway-related mRNAs including IFN‑β, ISG15, IL-6 and TNF-α were determined with RT-qPCR, and the phosphorylation levels of IRF3 and STING proteins were investigated using Western blotting.

Results: Compared with the mice in the model group, the LXJDHYF-treated mice exhibited milder hepatocyte necrosis and inflammatory cell infiltration in the liver with significantly reduced hepatocyte apoptosis. LXJDHYF treatment also significantly lowered serum levels of ALT, AST, TBil, IL-6 and TNF-α in ACLF mice and effectively suppressed the expressions of cGAS-STING signaling pathway-related mRNA in both the BMDMs and the liver tissues and the phosphorylation of IRF3 and STING proteins in the BMDMs.

Conclusions: LXJDHYF can significantly improve liver function and attenuate inflammation in ACLF mice possibly by inhibiting excessive activation of the cGAS-STING signaling pathway.