[Predictive value of cardiac magnetic resonance imaging for adverse left ventricular remodeling after acute ST-segment elevation myocardial infarction]

OBJECTIVE

To assess the value of cardiac magnetic resonance (CMR) imaging for predicting adverse left ventricular remodeling in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

We retrospectively analyzed the clinical data and serial CMR (cine and LGE sequences) images of 86 STEMI patients within 1 week and 5 months after percutaneous coronary intervention (PCI), including 25 patients with adverse LV remodeling and 61 without adverse LV remodeling, defined as an increase of left ventricular end-systolic volume (LVESV) over 15% at the second CMR compared to the initial CMR. The CMR images were analyzed for LV volume, infarct characteristics, and global and infarct zone myocardial function. The independent predictors of adverse LV remodeling following STEMI were analyzed using univariate and multivariate Logistic regression methods.

RESULTS

The initial CMR showed no significant differences in LV volume or LV ejection fraction (LVEF) between the two groups, but the infarct mass and microvascular obstructive (MVO) mass were significantly greater in adverse LV remodeling group (P < 0.05). Myocardial injury and cardiac function of the patients recovered over time in both groups. At the second CMR, the patients with adverse LV remodeling showed a significantly lower LVEF, a larger left ventricular end-systolic volume index (LVESVI) and a greater extent of infarct mass (P < 0.001) with lower global peak strains and strain rates in the radial, circumferential, and longitudinal directions (P < 0.05), infarct zone peak strains in the 3 directions, and infarct zone peak radial and circumferential strain rates (P < 0.05). The independent predictors for adverse LV remodeling following STEMI included the extent of infarct mass (AUC=0.793, 95% CI: 0.693-0.873; cut-off value: 30.67%), radial diastolic peak strain rate (AUC=0.645, 95% CI: 0.534-0.745; cut-off value: 0.58%), and RAAS inhibitor (AUC= 0.699, 95% CI: 0.590-0.793).

CONCLUSION

The extent of infarct mass, peak radial diastolic strain rate, and RAAS inhibitor are independent predictors of adverse LV remodeling following STEMI.

[Effect of Pp2cm Gene Silencing on Mouse Macrophage Resistance Against Staphylococcus aureus Infection via TLR Pathway]

Objective

To investigate the effect of silencing protein phosphatase 2cm ( Pp2cm) gene on the expression of inflammatory factors in macrophages infected with Staphylococcus aureus ( S. aureus) and the mechanisms involved.

Methods

The effects of Pp2cm knockdown on inflammatory factors, proliferation, apoptosis, and Toll-like receptor (TLR) signaling were analyzed in RAW 264.7 cells, a murine macrophage cell line, transfected with adenovirus (Ad). The cells were divided into four groups, including Ad-Ctrl group, Ad- Pp2cm group, Ad-Ctrl+ S. aureus group and Ad- Pp2cm+ S. aureus group. Cell transfection was achieved by separately introducing control adenovirus (Ad-Ctrl) or adenovirus targeting the Pp2cm gene (Ad- Pp2cm) and inflammation or the absence of inflammation was induced by applying or not applying S. aureus. The expression of tumor necrosis factor-alpha ( TNF-α), interleukin-1β ( IL-1 β), TLR2, TLR4, Toll-like receptor adaptor protein ( Tirap) and myeloid differentiation factor 88 ( Myd88) was determined by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). PP2Cm protein expression was determined by Western blot. Cell proliferation was determined by cell counting kit-8 (CCK-8) assay and cell apoptosis was measured by flow cytometry.

Results

The expression of Pp2cmgene and PP2Cm protein was downregulated in the Ad- Pp2cm group when compared to the Ad-Ctrl group, with the diference showing statistical significance ( P<0.05). When compared to those of the Ad-Ctrl+ S. aureus group, macrophages in the Ad- Pp2cm+ S. aureus group showed significantly increase in the TNF- α and IL-1 β gene levels ( P<0.01). Furthermore, the Ad- Pp2cm group demonstrated elevated gene expression levels of TLR2, TLR4, Tirap and Myd88 in macrophages when compared to the Ad-Ctrl group, with the difference showing statistical significance ( P<0.05). There were no statistically significant differences in cell apoptosis and proliferation between the Ad-Ctrl and Ad- Pp2cm groups.

Conclusions

Silencing Pp2cm gene promotes the inflammatory response of macrophages to S. aureus infection. Moreover, the TLR pathway plays an important role in the inflammatory activation of macrophages.

[Hippocampal Development Deviation and Its Relationship With Cognition in Major Psychiatric Disorders]

Objective

To investigate hippocampal development deviation and its association with cognition in patients with major psychiatric disorders (MPDs), including schizophrenia, bipolar disorder and major depressive disorder.

Methods

The T1-weighted MRI data of 174 first-episode drug-naïve schizophrenia (FES) atients, 169 bipolar disorder (BD) patients, 184 major depressive disorder (MDD) patients, and 321 healthy controls were collected and their hippocampal volume was extracted after preprocessing with Freesurfer 5.3. A normative neurodevelopment model was applied to calculate the hippocampal deviation scores. Data on cognitive functions, including visual memory, attention, spatial working memory, were collected. Comparison by different sexes was made to identify difference between the hippocampal development deviation scores of the control group and those of the disease groups. We also investigated the moderating effect of age on the deviation score and explored the association between the deviation score and cognitive function.

Results

The hippocampal development deviation scores of patients with MPDs were significantly lower than those of the healthy controls (false discovery rate [FDR]-P<0.05). Analysis of the moderating effect of age revealed lower deviation scores in young patients (<[25.83-28.56] yr.) and higher deviation scores in old patients (>[35.87-54.35] yr.) in comparison with those of the healthy controls. The right hippocampal deviation scores in male FES patients were positively correlated with the number of errors for tasks concerning spatial working memory ( r=0.32, FDR-P=0.04).

Conclusion

Our findings suggest abnormal hippocampal development in MPDs patients and its different distribution in MPDs patients of different age groups. The hippocampal development deviation score may provide a new perspective for further understanding of etiology in MPDs.

[Frequency-Specific Alterations of Spontaneous Brain Activity in First-Episode Drug-Naïve Schizophrenia]

Objective

To investigate frequency-specific alterations of spontaneous brain activity in first-episode drug-naïve schizophrenia (SZ) patients and the associations with clinical symptoms.

Methods

We collected the resting-state functional MRI (rs-fMRI) data from 84 first-episode drug-naïve SZ patients and 94 healthy controls (HCs) and calculated the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of four frequency bands, including slow-2, slow-3, slow-4, and slow-5. Two-sample t-tests were used to evaluate the intergroup differences in ALFF and ReHo, while partial correlation analyses were conducted to explore the associations between abnormal ALFF and ReHo and the severity of clinical symptoms in the SZ group.

Results

Compared with HCs, the SZ group showed reduced ALFF in superior cerebellum and cerebellar vermis across slow-2, slow-3, and slow-4 bands, while increased ALFF was found in left superior temporal gyrus, middle temporal gyrus, and superior temporal pole at slow-4 band. Moreover, reduced ReHo was observed in the right precentral and postcentral gyri at slow-3 band in the SZ group. Additionally, the ALFF of left superior temporal gyrus, middle temporal gyrus, and superior temporal pole in slow-4 band showed a trend of positive correlation with the excited factor score of Positive and Negative Syndrome Scale (PANSS) in the SZ group.

Conclusion

Our results suggest that local alterations of spontaneous brain activity were frequency-specific in first-episode drug-naïve SZ patients.

[Effects of Long-Term Ethanol Consumption on Learning-Memory Functions in Mice and the Mechanisms Involved]

Objective

To investigate the effect of long-term ethanol consumption on learning-memory functions in mice and the mechanisms involved.

Methods

Thirty male C57BL6/J mice were randomly assigned to 3 groups, with 10 mice in each group. The three groups included a control group in which the mice were given water ad libitum for 30 days, a long-term ethanol consumption group, or the EtOH group, in which the mice were given 6% (volume fraction) ethanol ad libitum for 30 days, and a long-term alcoholism group, or the EtOH+G group, in which the mice were given 5% (volume fraction) ethanol ad libitum for 30 days plus intermittent intragastric gavage of 20% ethanol at 3.5 g per kilogram body mass once every three days. After 30 days, the learning-memory functions of the mice were evaluated. At the conclusion of the experiment, the brain tissue of the mice was collected in order to examine the oxygen consumption rate (OCR) of mitochondria, the levels of pan-acetylation and protein oxidative stress in the hippocampal tissue, and the expression of sirtuin-3 (SIRT3) in hippocampus.

Results

Morris water maze test showed that, compared with those of the control group, the times of crossing the platform and the percentage of platform time in the EtOH group and the EtOH+G group were both lower, and the EtOH+G group had the lowest results ( P<0.05). Western blot results showed that long-term ethanol intake increased the levels of protein oxidative stress and pan-acetylation in the hippocampal tissue and down-regulated SIRT3 expression of hippocampal mitochondria. The results of mitochondrial complex Ⅱ respiration showed that the brain mitochondrial 3-state respiration in the EtOH group and the EtOH+G group was lower than that in the control group ( P<0.05). Compared that with the control group, the mitochondrial maximum respiration in EtOH+G group was decreased ( P<0.05).

Conclusions

Both long-term ethanol consumption and long-term alcoholism can reduce learning-memory functions and long-term alcoholism has the greater impact of the two. The potential mechanism may involve the down-regulation of the expression of SIRT3 protein in the hippocampus, which results in an increased level of pan-acetylation and enhanced expression of oxidative stress protein in the hippocampus, affects the mitochondrial functions of the brain, inhibits the oxidative phosphorylation capacity of mitochondrial complex Ⅱ, reduces the ATP energy supply of the brain tissue, and thus affects the learning-memory function.

[The Effect of Short-Term Intermittent Hypoxia Exposure on Mouse Myocardial Oxidative Stress and Cardiac Function]

OBJECTIVE

To investigate the effect of short-term intermittent hypoxia (IH) on the structure and function of mouse myocardium.

METHODS

Thirty male C57BL6/J mice were randomly assigned to two groups, a control (Con) group and an IH group exposed to hypoxic treatment at atmospheric pressure. The IH group received 10% oxygen pretreatment for 8 hours per day on 14 consecutive days, while the Con group was exposed to normoxia environment and all the other treatment the group received were identical to those given to the IH group, The body mass of the mice was monitored daily during the treatment. The exercise tolerance and the cardiac function of isolated heart were assessed at the end of IH exposure. Additionally, analysis was conducted regarding myocardial enzymology, histology, and other indicators relevant to oxidative stress, including protein carbonylation and lipid peroxidation.

RESULTS

There was no significant difference in the exercise tolerance between the two groups. Nevertheless, IH mice showed enhanced cardiac function during isolated heart perfusion ( P<0.05). As compared to the control group, prominent alterations of myocardial structure were detected by transmission electron microscopy of the IH heart, accompanied by elevated creatine kinase-MB levels ( P<0.05). The levels of myocardial reactive oxygen species, protein carbonylation and lipid peroxidation were all significantly upregulated in the IH group as compared to the control group ( P<0.05).

CONCLUSION

IH exposure induced myocardial oxidative stress damage and myofibrillar structural alteration in mice, but did not impair the exercise tolerance of the mice or the contractile function of the isolated heart.

[Perinatal Outcomes of Using Ursodeoxycholic Acid to Treat Monochorionic and Dichorionic Twin Pregnancy Complicated by Intrahepatic Cholestasis of Pregnancy]

OBJECTIVE

To study the effect of using ursodeoxycholic acid (UDCA) to treat monochorionic and dichorionic twin pregnancies complicated by intrahepatic cholestasis of pregnancy (ICP) and to examine the differences in perinatal outcomes.

METHODS

A total of 406 twin-carrying pregnant women who had ICP and received care at West China Second Hospital, Sichuan University between January 1, 2015 and November 1, 2018 were included in the study. The clinical data of monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twins with ICP were analyzed. Analysis was done to compare the treatment effect for lowering serum total bile acid (TBA) and the perinatal outcomes with simple UDCA medication or combination medication.

RESULTS

There were no statistically significant differences in TBA levels, early-onset ICP, simple UDCA medication or combination medication, neonatal Apgar score, birth weight, length of hospital stay, C-section rate, and perinatal mortality between the MCDA and the DCDA twin groups with ICP. However, maternal age, BMI, scarred uterus, in vitro fertilization-embryo transfer, preeclampsia, twin comorbidity rate of the two groups showed statistical differences. Further comparison between twin pregnancies with mildly-elevated TBA and those with severely-elevated TBA showed significant difference in preterm birth rate ( P<0.05).

CONCLUSION

Simple UDCA medication or combination medication may have the same therapeutic effect on MCDA and DCDA twin pregnancies with ICP. Monochorionic twin pregnancy, twin comorbidities and pregnancy complications were still important factors affecting pregnancy outcomes of twin pregnancies with ICP. Twin pregnancies with slightly elevated TBA have been managed as severe ICP, which may be associated with increased iatrogenic preterm births.

[Effect of Ketone Body β-Hydroxybutyrate to Attenuate Inflammation-Induced Mitochondrial Oxidative Stress in Vascular Endothelial Cells]

OBJECTIVE

To investigate the regulatory function and mechanism of β-hydroxybutyrate (β-OHB), a ketone body, on the mitochondrial oxidative stress of inflammatory human umbilical vein endothelial cells (HUVECs).

METHODS

Lipopolysaccharide (LPS) and adenosine triphosphate (ATP) were used to induce macrophages to release proinflammatory factors, and the culture supernatant was collected as a macrophage-conditioned medium (MCM) to culture HUVECs. A total of 7 groups of cells were used in the study: ①control group, or normal cultured HUVECs; ②MCM group, or the MCM-cultured HUVECs; groups ③ to ⑦ were all HUVECs co-cultured with different reagents, including ③MCM+β-OHB group, ④MCM+N-acetylcysteine (NAC) group, ⑤MCM+β-OHB+NAC group, ⑥MCM+β-OHB+histone deacetylase agonist ITSA1 group, and ⑦MCM+β-OHB+histone deacetylase inhibitor Entinostat group. MitoSOX immunofluorescence staining was conducted to analyzes the mitochondrial superoxide levels, real-time fluorescent quantitative polymerase chain reaction (RT-qPCR) was performed to examine the mRNA expression of antioxidant genes, and Seahorse mitochondrial energy analyzer was used to measure mitochondrial aerobic respiration capacity.

RESULTS

Compared with the control group, mitochondrial superoxide production was significantly increased in the MCM cultured HUVECs cells, while β-OHB treatment significantly inhibited mitochondrial superoxide production, which was accompanied by an increase in the mRNA expression of antioxidant genes, and significant increase in the basal mitochondrial oxygen consumption rate and respiratory reserve capacity. NAC treatment did not further enhance the protective effect of β-OHB on mitochondrial functions. In addition, ITSA1 treatment could completely offset the antioxidant and mitochondrial protective effects of β-OHB, and these stated effects were still maintained after Entinostat treatment.

CONCLUSION

The ketone body β-OHB attenuates the mitochondrial oxidative stress of vascular endothelial cells through activating the antioxidant pathway and inhibiting histone deacetylase activity.

[Characteristics and Significance of Gene Expression Changes in Peripheral Blood of Lumbar Disc Extrusion Patients before and after Nonoperative Treatment]

OBJECTIVE

To define the gene expression characteristics in the peripheral blood of patients with lumbar disc extrusion (LDE) and the effect of nonoperative treatment on the gene expression.

METHODS

DNA microarray was used to identify semi-quantitatively the differentially expressed genes (DEGs) in the peripheral blood of patients with LDE and that of the healthy controls and the variation trend of these DEGs after nonoperative treatment. Enrichment analysis was done to reveal the functional characteristics of these DEGs, and network analysis was done to identify key genes that contribute to gene dysregulation. The levels of these key genes were measured by qRT-PCR to examine their expression in LDE patients and the controls, and the effect of nonoperative treatment on the expression level.

RESULTS

We identified 153 DEGs in the peripheral blood of LDE patients and healthy controls, including 131 upregulated genes and 22 downregulated genes. Enrichment analysis revealed that most of the DEGs were related to immunity and the inflammatory response. Network analysis revealed that toll-like receptor 4 ( TLR4 ), matrix metallopeptidase 9 ( MMP9) and myeloperoxidase ( MPO), cathelicidin antimicrobial peptide ( CAMP), resistin ( RETN), toll-like receptor 5 ( TLR5) were the key genes in the protein-protein interaction network. These key genes were all enriched into the terms releated to immunity and the inflammatory response. The patients experienced pain relief after nonoperative treatment. Among the 153 DEGs, TLR5 , interleukin 1 receptor antagonist ( IL1 RN) and solute carrier family 8 member A1 ( SLC8 A1) were downregulated after nonoperative treatment. qRT-PCR revealed that the levels of TLR4, MMP9 , MPO, CAMP, RETN, TLR5, IL1 RN and SLC8 A1 in the peripheral blood of the LDE patients were higher than those of the healthy control group ( P<0.05). In addition, TLR5 , IL1 RN and SLC8 A1 expression levels decreased after treatmentin in comparison with the levels before treatment ( P<0.05).

CONCLUSION

Gene expression in the peripheral blood of LDE patients was characterized by the dysregulation of immune and inflammatory response-related genes, among which, TLR4, MMP9, MPO, CAMP, RETN and TLR5, the genes relevant to immune and inflammatory response, played a key role in the dysregulation of gene expression in the peripheral blood of LDE patients. The outcome of non-operative treatment may be related to the downregulation of the overexpressed TLR5, IL1 RN and SLC8 A1 in the peripheral blood of patients.

[Pregnane X receptor promotes programmed cell death protein 4 expression in HepG2 cells]

OBJECTIVE

To investigate the role of pregnane X receptor (PXR) in the regulation of programmed cell death proteins (PDCDs) in HepG2 cells and explore the underlying molecular mechanism.

METHODS

HepG2 cells were treated with PXR agonist rifampicin (10 μmol/L) or SR12813 (1 μmol/L) for 24 h, using DMSO as the negative control. HepG2 cells were infected with constitutively activated PXR adenovirus (VP-PXR) for 36 h, with the cells infected with Mock as the negative control. The mRNA levels of PDCD2, PDCD4, PDCD5, and PDCD6 and the expression of miRNA21 were detected using qRT-PCR, and the protein level of PDCD4 was detected with Western blotting. Bioinformatic analysis was performed to predict the potential PXRresponsive elements (PXREs) motifs in the promotor region of human PDCD4.

RESULTS

The expressions of PDCD5 and PDCD6 mRNA did not differ significantly between rifampicin-treated and the control cells, while PDCD4 mRNA expression increased (t=4.209, P=0.008) and PDCD2 mRNA decreased significantly (t=-2.875, P=0.017) in rifampicin-treated cells. The mRNA expressions of PDCD2, PDCD5 and PDCD6 showed no significant difference between SR12813-treated cells and the control cells, while PDCD4 mRNA expression increased obviously in SR12813-treated cells (t=4.574, P=0.006). The PXR target gene MDR1 also increased significantly in the rifampicin- and SR12813-treated cells compared with the control cells (P=0.020 and 0.01, respectively). Infection of the cells with VP-PXR adenovirus resulted in significantly increased expression of PDCD4 and MDR1 mRNA as compared with Mock group (t=3.343, P=0.000; t=3.343, P=0.024, respectively) without causing obvious changes in PDCD2 and PDCD6 mRNA expressions. The protein level of PDCD4 increased significantly in both rifampicin (t= 2.779, P=0.025) group and VP- PXR group (t=3.066, P=0.012). The expression of miRNA21, the negative regulatory factor of PDCD4, did not differ significantly between PXR agonist group and the control group. Informatic analysis revealed the presence of putative PXREs in the 5'-flanking region of PDCD4 gene.

CONCLUSIONS

Our findings demonstrate that PXR agonism in HepG2 cells increases the expression of PDCD4, which is independent of miRNA21 pathway, and PDCD4 may be a target gene of PXR in HepG2 cells.