VCAM-1+ hUC-MSCs Exert Considerable Neuroprotection Against Cerebral Infarction in Rats by Suppression of NLRP3-Induced Pyroptosis.

Mesenchymal stem/stromal cells (MSCs) are spindle-like heterogeneous cell populations with advantageous bidirectional immunomodulatory and hematopoietic support effects. Vascular cellular adhesion molecule-1 (VCAM-1)+ MSCs have been reported to exhibit immunoregulatory and proangiogenic capacities. Here, we studied the effects of VCAM-1+ human umbilical cord (hUC)-MSCs on neuroprotection against cerebral infarction. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO), and VCAM-1- and VCAM-1+ hUC-MSCs were intravenously injected into the rat 4 h post-MCAO surgery. Thereafter, modified neurological severity scores (mNSS) were determined, and the Morris water maze test, 2,3,5-triphenyltetrazolium chloride (TTC), hematoxylin and eosin (H&E), Nissl, TUNEL staining, and qRT-PCR were conducted. Following induction of oxygen-glucose deprivation/reoxygenation (OGD/R), SH-SY5Y cells were co-cultured with VCAM-1- and VCAM-1+ hUC-MSCs. CCK-8, flow cytometry, ELISA, and western blot analyses were performed in vitro. Compared with VCAM-1- hUC-MSCs, administration of VCAM-1+ hUC-MSCs revealed improved therapeutic efficacy against cerebral infarction in rats, as confirmed by lower mNSS scores and infarct volumes, as well as improved learning and memory capacities. In addition, VCAM-1+ hUC-MSCs exhibited improved efficacy against neurological defects in rats with cerebral infarction, accompanied by inhibition of the NLRP3-mediated inflammatory response. VCAM-1+ hUC-MSC co-culture improved the viability and diminished NLRP3-mediated inflammatory response in OGD/R-treated SH-SY5Y cells. Moreover, NLRP3 overexpression in SH-SY5Y cells prevented the beneficial effects of VCAM-1+ hUC-MSC co-culture. Overall, our findings demonstrated the relevance of VCAM-1+ hUC-MSC-based cytotherapy for preclinical neuroprotection against cerebral infarction.

Aberrant Dendritic Cell Subsets in Patients with Myasthenia Gravis and Related Clinical Features.

INTRODUCTION: Dendritic cells (DCs) play critical roles in the pathogenesis of myasthenia gravis (MG), and a series of DC-based experimental strategies for MG have recently been developed. However, the definite roles of different DC subsets in the mechanism of MG have scarcely been covered by previous studies. The present study aimed to investigate the levels of three main DC subsets, plasmacytoid DCs (pDCs) (CD303 positive) and two distinct subsets of conventional DCs (cDCs), namely CD1c+ cDCs and CD141+ cDCs, in MG patients and analyze related clinical features. METHODS: From January 2016 to December 2020, 160 newly diagnosed MG patients and matched healthy controls (n = 160) were included in the study, and their clinical data were collected. The blood samples from MG patients before treatment and controls were collected for flow cytometry analysis. A total of 14 MG thymoma, 24 control thymoma, and 3 thymic cysts were used to immunostain the DC subsets. RESULTS: The flow cytometry analysis showed a significantly higher frequency of circulating pDCs, CD1c+ cDCs, and CD141+ cDCs in MG patients than in healthy controls (p < 0.001 for all). Patients with early-onset MG (<50 years old) had a lower frequency of circulating pDCs but a higher frequency of circulating CD1c+ cDCs than those with late-onset MG (≥50 years old) (p = 0.014 and p = 0.025, respectively). The frequency of circulating pDCs was positively associated with the clinical severity of late-onset MG patients (r = 0.613, p < 0.001). 64.3% (9/14) of MG thymoma is of type B2 under the World Health Organization classification, which is higher than that in control thymoma (33.3%, 8/24) (p = 0.019). For type B2 thymoma, there were significantly more pDCs but fewer CD1c+ cDCs in MG thymoma than in the controls. CONCLUSION: The distribution of aberrant pDCs, CD1c+ cDCs, and CD141+ cDCs in MG patients displayed age- and thymoma-related differences, which may contribute to the impaired immune tolerance and lead to the onset of MG.

Integrated investigation of DNA methylation, gene expression and immune cell population revealed immune cell infiltration associated with atherosclerotic plaque formation.

BACKGROUND: The clinical consequences of atherosclerosis are significant source of morbidity and mortality throughout the world, while the molecular mechanisms of the pathogenesis of atherosclerosis are largely unknown. METHODS: In this study, we integrated the DNA methylation and gene expression data in atherosclerotic plaque samples to decipher the underlying association between epigenetic and transcriptional regulation. Immune cell classification was performed on the basis of the expression pattern of detected genes. Finally, we selected ten genes with dysregulated methylation and expression levels for RT-qPCR validation. RESULTS: Global DNA methylation profile showed obvious changes between normal aortic and atherosclerotic lesion tissues. We found that differentially methylated genes (DMGs) and differentially expressed genes (DEGs) were highly associated with atherosclerosis by being enriched in atherosclerotic plaque formation-related pathways, including cell adhesion and extracellular matrix organization. Immune cell fraction analysis revealed that a large number of immune cells, especially macrophages, activated mast cells, NK cells, and Tfh cells, were specifically enriched in the plaque. DEGs associated with immune cell fraction change showed that they were mainly related to the level of macrophages, monocytes, resting NK cells, activated CD4 memory T cells, and gamma delta T cells. These genes were highly enriched in multiple pathways of atherosclerotic plaque formation, including blood vessel remodeling, collagen fiber organization, cell adhesion, collagen catalogic process, extractable matrix assembly, and platelet activation. We also validated the expression alteration of ten genes associated with infiltrating immune cells in atherosclerosis. CONCLUSIONS: In conclusion, these findings provide new evidence for understanding the mechanisms of atherosclerotic plaque formation, and provide a new and valuable research direction based on immune cell infiltration.

IFN-γ-Primed hUCMSCs Significantly Reduced Inflammation via the Foxp3/ROR-γt/STAT3 Signaling Pathway in an Animal Model of Multiple Sclerosis.

Our previous study showed that interferon gamma (IFN-γ) might enhance the immunosuppressive properties of mesenchymal stem cells (MSCs) by upregulating the expression of indoleamine 2,3-dioxygenease. Therefore, we treated experimental autoimmune encephalomyelitis (EAE) mice, an animal model of multiple sclerosis (MS), with IFN-γ-primed human umbilical cord MSCs (IFN-γ-hUCMSCs). This study aimed to investigate the potential therapeutic effects of IFN-γ-hUCMSCs transplantation and to identify the biological pathways involved in EAE mice. Firstly, the body weights and clinical scores of EAE mice were recorded before and after treatment. Then, the inflammatory cytokine levels in splenic cell supernatants were quantified by enzyme-linked immunosorbent assay. Finally, the mRNA expression levels of signal transducer and activator of transduction 3 (STAT3), retinoic acid-related orphan receptor gamma t (ROR-γt), and forkhead box P3 (Foxp3) were detected by quantitative reverse transcription polymerase chain reaction. We observed that IFN-γ-hUCMSCs transplantation significantly alleviated body weight loss and decreased the clinical scores of mice. Additionally, IFN-γ-hUCMSCs transplantation could regulate the production of inflammatory cytokines, interleukin (IL)-10 and IL-17, thereby showing more potent treatment efficacy than human umbilical cord MSCs (hUCMSCs) transplantation (p < 0.05). Compared with the EAE group, the expressions of STAT3 and ROR-γt in the transplantation groups were significantly decreased, but the expression of Foxp3 was significantly upregulated in the IFN-γ-hUCMSCs transplantation group compared to that in the hUCMSCs transplantation group. We assumed that IFN-γ-hUCMSCs may affect the balance of T helper 17 (Th17) cells/regulatory T cells (Tregs) through the Foxp3/ROR-γt/STAT3 signaling pathway to reduce the inflammatory response, thereby improving the clinical symptoms of EAE mice. Our study demonstrated that transplantation of IFN-γ-hUCMSCs could reduce inflammation in EAE mice via the Foxp3/ROR-γt/STAT3 signaling pathway, highlighting the therapeutic effects of IFN-γ-hUCMSCs in patients with MS.

IRE1α-XBP1 Affects the Mitochondrial Function of Aß25-35-Treated SH-SY5Y Cells by Regulating Mitochondria-Associated Endoplasmic Reticulum Membranes.

Background: Neurotoxicity induced by the amyloid beta (Aß) peptide is one of the most important pathological mechanisms of Alzheimer's disease (AD). Activation of the adaptive IRE1α-XBP1 pathway contributes to the pathogenesis of AD, making it a potential target for AD therapeutics. However, the mechanism of IRE1α-XBP1 pathway involvement in AD is unclear. We, therefore, investigated the effect of the IRE1α-XBP1 axis in an in vitro AD model and explored its potential mechanism. Methods: The human neuroblastoma cell line, SH-SY5Y, was used. Cells were treated with Aß25-35, with or without 4µ8c, an inhibitor of IRE1α. Cells were collected and analyzed by Western blotting, quantitative real-time PCR, electron microscopy, fluorescence microscopy, calcium imaging, and other biochemical assays. Results: Aß-exposed SH-SY5Y cells showed an increased expression of XBP1s and p-IRE1α. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and calcium imaging analysis showed that the IRE1α inhibitor, 4µ8c, reduced Aß-induced cytotoxicity. Increased levels of ATP, restoration of mitochondrial membrane potential, and decreased production of mitochondrial reactive oxygen species after Aß treatment in the presence of 4µ8c showed that inhibiting the IRE1α-XBP1 axis effectively mitigated Aß-induced mitochondrial dysfunction in SH-SY5Y cells. Furthermore, Aß treatment increased the expression and interaction of IP3R, Grp75, and vdac1 and led to an increased endoplasmic reticulum (ER)-mitochondria association, malfunction of mitochondria-associated ER-membranes (MAMs), and mitochondrial dysfunction. These deficits were rescued by inhibiting the IRE1α-XBP1 axis. Conclusion: These findings demonstrate that Aß peptide induces the activation of the IRE1α-XBP1 axis, which may aggravate cytotoxicity and mitochondrial impairment in SH-SY5Y cells by targeting MAMs. Inhibition of the IRE1α-XBP1 axis provides the protection against Aß-induced injury in SH-SY5Y cells and may, therefore, be a new treatment strategy.

Detection and significance of exosomal mRNA expression profiles in the cerebrospinal fluid of patients with meningeal carcinomatosis.

Exosomes are cell-derived membrane vesicles with cargo that can be transported into receiver cells to exert their biological roles. Exosomal RNA signature profiles and exosome-derived proteomics are often used to explore the molecular regulation of diseases, and can mirror the conditional state of their tissue of origin, thus serving as biomarkers. The onset of meningeal carcinomatosis (MC) is concealed, and early diagnosis is difficult. To enable early diagnosis of MC, it is essential to identify new biomarkers. Few studies have investigated the function of exosomes in MC. In this study, high-throughput sequencing was used to examine the mRNA profiles of exosomes in the cerebrospinal fluid (CSF) of patients with MC. We further analyzed the functions and signaling pathways associated with the differentially expressed genes in exosomes to reveal the putative mechanisms by which the exosomal mRNAs function in MC. In summary, this study identified biomarker candidates for MC, and provided new insights into the significant role of exosomal mRNA regulation in MC.

Vascular endothelial growth factor alleviates mitochondrial dysfunction and suppression of mitochondrial biogenesis in models of Alzheimer's disease.

PURPOSE: Mitochondrial dysfunction is a prominent feature of Alzheimer's disease (AD). As vascular endothelial growth factor (VEGF) has been shown to be protective in AD, the aim of this study was to investigate the effects of VEGF on mitochondrial function in models of AD. MATERIALS AND METHODS: Adeno associated virus (AAV)-VEGF was injected into the hippocampus of APP/PS1 mice. Cognitive function was assessed in these mice with use of the Morris water maze (MWM) and ß-amyloid (Aß) levels in the hippocampus were also measured. Cell viability and reactive oxygen species (ROS) levels were determined in the SH-SY5Y cells treated with Aß25-35 which served as a cell model of AD. Transmission electron microscopy (TEM) was used to evaluate structural changes in mitochondria and mitochondrial DNA (mtDNA) copy number and mitochondrial membrane potential (MMP) were also recorded. Finally, we investigated the effects of VEGF upon mitochondrial biogenesis, autophagy and mitochondrial autophagy (mitophagy) as determined both in vivo and in vitro with western blots. RESULTS: VEGF treated mice showed improvements in spatial learning and memory along with reduced Aß levels. VEGF protected SH-SY5Y cells against Aß25-35 induced neurotoxicity as demonstrated by increased cell viability and decreased ROS production. Associated with these effects were improvements in mitochondrial structure and function, and increased numbers of mitochondria resulting from stimulation of mitochondrial biogenesis. CONCLUSIONS: VEGF alleviates Aß related patholoy in models of AD. In part, these beneficial effects of VEGF result from protection of mitochondria and stimulation of mitochondrial biogenesis.

Stem Cell Therapy for Alzheimer's Disease.

Alzheimer's disease (AD) is the most common neurodegenerative disease caused by eventually aggregated amyloid ß (Aß) plaques in degenerating neurons of the aging brain. These aggregated protein plaques mainly consist of Aß fibrils and neurofibrillary tangles (NFTs) of phosphorylated tau protein. Even though some cholinesterase inhibitors, NMDA receptor antagonist, and monoclonal antibodies were developed to inhibit neurodegeneration or activate neural regeneration or clear off the Aß deposits, none of the treatment is effective in improving the cognitive and memory dysfunctions of the AD patients. Thus, stem cell therapy represents a powerful tool for the treatment of AD. In addition to discussing the advents in molecular pathogenesis and animal models of this disease and the treatment approaches using small molecules and immunoglobulins against AD, we will focus on the stem cell sources for AD using neural stem cells (NSCs); embryonic stem cells (ESCs); and mesenchymal stem cells (MSCs) from bone marrow, umbilical cord, and umbilical cord blood. In particular, patient-specific-induced pluripotent stem cells (iPS cells) are proposed as a future prospective and the challenges for the treatment of AD.

Transplantation of IFN-γ Primed hUCMSCs Significantly Improved Outcomes of Experimental Autoimmune Encephalomyelitis in a Mouse Model.

The aim of this study was to investigate potential therapeutic effects of IFN-γ primed human umbilical cord mesenchymal stem cell (IFN-γ-hUCMSCs) transplantation on experimental autoimmune encephalomyelitis (EAE) in mice. In this study, EAE mouse model was established by MOG35-55 immunization method. Outcomes of the EAE mice in terms of body weight and clinical symptoms were analyzed. Electromyography (EMG) was performed to evaluate nerve conduction. ELISA was applied to quantify inflammatory cytokine levels in serum. Our results showed that IFN-γ could up-regulate protein expression of indoleamine 2, 3-dioxygenease 1 (IDO1), an important molecule released by MSCs to exert their immune suppressive activity (p < 0.01). In this study treatment efficacy for EAE was compared between transplantation of hUCMSCs alone and the IFN-γ-hUCMSCs which were cultured in the presence of IFN-γ for 48 h prior to be harvested for transplantation. Compared with hUCMSCs alone and control (PBS transfusion) group, transplantation of the IFN-γ-hUCMSCs could significantly alleviate the body weight loss and clinical symptoms of EAE mice (p < 0.05). Consistently EMG latency was significantly improved in treatment groups (p < 0.001), and the IFN-γ-hUCMSCs group was even better than the hUCMSCs group (p < 0.05). Moreover, the concentrations of IL-17A and TNF-α in serum of the mice treated by IFN-γ-hUCMSCs were significantly lower than hUCMSCs alone and controls, respectively (p < 0.05). In few of the roles of IL-17A and TNF-α in the pathogenesis of EAE, IFN-γ-hUCMSCs treatment associated-suppression of IL-17A and TNF-α expression may contribute in part to their therapeutic effects on EAE. In sum, our study highlights a great clinical potential of IFN-γ-hUCMSCs for multiple sclerosis (MS) treatment.

Orexin-A exacerbates Alzheimer's disease by inducing mitochondrial impairment.

Alzheimer's disease (AD) is a progressive neurodegenerative disease which is characterized by the accumulation of amyloid-ß peptide (Aß). Orexin-A is a neuropeptide which has been reported to participate in the pathogenesis of AD. Thus, we aimed to investigate the possible mechanism by which Orexin-A acts in AD. APP/PS1 transgenic mice, an animal model of AD, were intracerebroventricularly injected with Orexin-A. Aß-treated SH-SY5Y cells were used as a cell model of AD and treated with Orexin-A. The Morris water maze test, fluorescence microscopy, enzyme-linked immunosorbent assay (ELISA), electron microscopy, real-time PCR, and other biochemical assays were conducted. The Morris water maze test showed that Orexin-A aggravated cognitive deficit in APP/PS1 mice. Using thioflavine-S staining and ELISA, we found that Orexin-A promoted Aß accumulation in APP/PS1 mice. By evaluating mitochondrial morphology, cytochrome c oxidase activity, ATP level, mitochondrial DNA copy number, and reactive oxygen species, we found that Orexin-A aggravated mitochondrial impairment in APP/PS1 mice and Aß-treated SH-SY5Y cells. Our results indicate that Orexin-A exacerbates AD by inducing mitochondrial impairment. This is a new mechanism that explains how Orexin-A participates in the pathogenesis of AD.

The effect of BACE1-AS on ß-amyloid generation by regulating BACE1 mRNA expression.

BACKGROUND: The BACE1 antisense transcript (BACE1-AS) is a conserved long noncoding RNA (lncRNA). The level of BACE1-AS is significantly increased and the level of the BACE1 mRNA is slightly increased in subjects with AD. BACE1-AS exerts a significant moderating effect on the expression of the BACE1 mRNA and promotes the formation of Aß. After the administration of Aß1-42 to SH-SY5Y cells and C57/BL6J mice, we detected the expression of BACE1-AS, BACE1 mRNA, and BACE1 protein, as well as the concentration of Aß1-40. Then, we silenced the expression of BACE1-AS in SH-SY5Y and 20E2 cells using siRNAs targeting BACE1-AS and detected its effects on the levels of the BACE1 mRNA and BACE1 protein and Aß1-40 generation. RESULTS: The administration of Aß1-42 increased the expression of BACE1-AS, BACE1 mRNA and protein, as well as the concentration of Aß1-40 in SH-SY5Y cells and the brains of C57BL/6J mice. Pretreatment with the BACE1-AS siRNA inhibited the effect of Aß1-42 on increasing the expression of BACE1-AS and BACE1, as well as the generation of Aß. CONCLUSIONS: The mechanism by which exogenous Aß1-42 induces BACE1 expression and Aß generation is mediated by BACE1-AS. BACE1-AS is involved in the mechanism regulating BACE1 expression and Aß generation in APPsw transgenic cells.

Methylation in the TP53 promoter is associated with ischemic stroke.

Cerebral ischemic stroke (IS) is a disease presenting high morbidity and mortality rates worldwide. Understanding of the pathogenesis underlying IS may facilitate the development of effective clinical therapeutic strategies and improve the prevention of this disease, decreasing its occurrence rate. Epigenetic alterations have recently attracted attention as possible mechanisms underlying IS. Additionally, tumor protein p53 (TP53) was identified to be involved in the pathophysiology of cerebral stroke. In the present study, the methylation status of the TP53 promoter was investigated in patients with IS and in age­matched healthy controls. The methylation status of the promoter of TP53 was significantly increased in patients with IS compared with healthy subjects. Additionally, the methylation level of the TP53 promoter was identified to be associated with carotid intima­media thickness, the degree of carotid atherosclerosis and the circulating levels of homocysteine in peripheral blood. The present findings may improve the understanding of the role of the epigenetic modifications of the TP53 promoter in IS pathogenesis.

Anti-inflammatory effects of bone marrow mesenchymal stem cells on mice with Alzheimer's disease.

Anti-inflammatory effects of bone marrow mesenchymal stem cells (BMSCs) on mice with Alzheimer's disease (AD) were investigated. Twenty amyloid precursor protein (APP)/presenilin-1 (PS1) double transgenic mice were randomly divided into two groups: the AD control group and the stem cell treatment group. The normal control group consisted of 10 non-transgenic mice. The stem cell treatment group was injected with BMSCs, and the two control groups were given the same volume of normal saline. The Morris water maze test was used to compare the memory function of mice, and the relative expression levels of ß-site APP cleaving enzyme 1 (BACE1) and α-2-macroglobulin (A2M) genes were detected by fluorescence quantitative polymerase chain reaction (qPCR). Amyloid ß (Aß)1-42 content in brain tissues of mice and inflammatory cytokines, interleukin (IL)-1, IL-2, IL-10, tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) were detected using enzyme-linked immunosorbent assay (ELISA). Compared with that in the AD control group, the escape latency in the water maze in the stem cell treatment group was shortened, the time of crossing the ring for the first time was decreased, but the frequency of crossing the ring was increased (P<0.05). Aß1-42 content in the AD control group was higher than that in the stem cell treatment group and the normal control group (P<0.05). The relative expression level of BACE1 gene in the stem cell treatment group was lower than that in the AD control group (P<0.05), but that of A2M gene was increased (P<0.05). At 14 days after treatment, the contents of IL-1, IL-2, TNF-α and IFN-γ in blood in the stem cell treatment group were lower than those in the AD control group (P<0.05). Human BMSCs can ameliorate the symptoms of AD by decreasing the levels of inflammatory cytokines and regulating the expression of Aß-related genes.

Exosomes Isolated From Human Umbilical Cord Mesenchymal Stem Cells Alleviate Neuroinflammation and Reduce Amyloid-Beta Deposition by Modulating Microglial Activation in Alzheimer's Disease.

Alzheimer's disease (AD) is the most common neurodegenerative disease characterized by excessive accumulation of the amyloid-ß peptide (Aß) in the brain, which has been considered to mediate the neuroinflammation process. Microglial activation is the main component of neuroimmunoregulation. In recent years, exosomes isolated from human umbilical cord mesenchymal stem cells (hucMSC-exosomes) have been demonstrated to mimic the therapeutic effects of hucMSCs in many inflammation-related diseases. In this study, exosomes from the supernatant of hucMSCs were injected into AD mouse models. We observed that hucMSC-exosomes injection could repair cognitive disfunctions and help to clear Aß deposition in these mice. Moreover, we found that hucMSC-exosomes injection could modulate the activation of microglia in brains of the mice to alleviated neuroinflammation. The levels of pro-inflammatory cytokines in peripheral blood and brains of mice were increased and the levels of anti-inflammatory cytokines were decreased. We also treated BV2 cells with hucMSC-exosomes in culture medium. HucMSC-exosomes also had inflammatory regulating effects to alternatively activate microglia and modulate the levels of inflammatory cytokines in vitro.

Glutathione-mimetic D609 alleviates memory deficits and reduces amyloid-ß deposition in an AßPP/PS1 transgenic mouse model.

Excessive extracellular deposition of amyloid-ß-peptide (Aß) in the brain is a pathological hallmark of Alzheimer's disease (AD). Oxidative stress is associated with the onset and progression of AD and contributes to Aß generation. Tricyclodecan-9-yl-xanthogenate (D609) is a glutathione (GSH)-mimetic compound. Although the antioxidant properties of D609 have been well-studied, its potential therapeutic significance on AD remains unclear. In the present study, we used a mouse model of AD to investigate the effects and the mechanism of action of D609 on AD. We found that D609 treatment significantly improved the spatial learning and alleviated the memory decline in the mice harboring amyloid precursor protein (APP) and presenilin-1 (PS1) double mutations (AßPP/PS1 mice). D609 treatment also increased GSH level, GSH and oxidative glutathione ratio, and superoxide dismutase activity, whereas decreased malondialdehyde and protein carbonyl levels, suggesting that D609 alleviated oxidative stress in AßPP/PS1 mice. In addition, D609 reduced ß-secretase 1 level and decreased amyloidogenic processing of AßPP, consequently reducing Aß deposition in the mice. Thus, our findings suggest that D609 might produce beneficial effects on the prevention and treatment of AD.

The Synergistic Neuroprotective Effects of Combined Rosuvastatin and Resveratrol Pretreatment against Cerebral Ischemia/Reperfusion Injury.

BACKGROUND: It is well accepted that both rosuvastatin and resveratrol exert neuroprotective effects on cerebral ischemia/reperfusion injury through some common pathways. Resveratrol has also been demonstrated to protect against cerebral ischemia/reperfusion injury through enhancing autophagy. Thus, we hypothesized that combined rosuvastatin and resveratrol pretreatment had synergistic effects on cerebral ischemia/reperfusion injury. MATERIALS AND METHODS: Adult male Sprague Dawley rats receiving middle cerebral artery occlusion surgery as animal model of cerebral ischemia/reperfusion injury were randomly assigned to 4 groups: control, resveratrol alone pretreatment, rosuvastatin alone pretreatment, and combined rosuvastatin and resveratrol pretreatment. Rosuvastatin (10 mg/kg) or resveratrol (50 mg/kg) was administrated once a day for 7 days before cerebral ischemia onset. RESULTS: We found that combined rosuvastatin and resveratrol pretreatment not only significantly decreased the neurologic defective score, cerebral infarct volume, the levels of caspase-3, and Interleukin-1ß (IL-1ß) but also significantly increased the ratios of Bcl-2/Bax and LC3II/LC3I, as well as the level of Becline-1, compared with resveratrol alone or rosuvastatin alone pretreatment group. Rosuvastatin alone pretreatment significantly increased the ratio of LC3II/LC3I and the level of Beclin-1. However, there were no significant differences in the neurologic defective score, cerebral infarct volume, the levels of caspase-3, IL-1ß, and Beclin-1, and the ratios of Bcl-2/Bax and LC3II/LC3I between resveratrol pretreatment group and rosuvastatin pretreatment group. CONCLUSIONS: Synergistically enhanced antiapoptosis, anti-inflammation, and autophagy activation might be responsible for the synergistic neuroprotective effects of combining rosuvastatin with resveratrol on cerebral ischemia/reperfusion injury.

Relationship between carotid artery sclerosis and blood pressure variability in essential hypertension patients.

OBJECTIVES: This study aimed to investigate the relationship between the presence of carotid arteriosclerosis (CAS) and blood pressure variability (BPV) in patients with essential hypertension. METHODS: One hundred and forty four essential hypertension patients underwent ambulatory BP monitoring for 24h after hospitalization. Common BPV metrics were calculated. General clinical parameters, including age, gender, height, weight, history of coronary heart disease, stroke, diabetes, hypertension, smoking and drink, were recorded. Biochemical indices were obtained from a blood test. Carotid intima-media thickness (IMT) and carotid plaques were assessed to separate patients into a non-CAS group (IMT≤0.9mm; n=82) and a CAS group (IMT>0.9mm; n=62). BPV metrics and clinical parameters were analyzed and compared between the two groups. Multivariate logistic regression analysis was performed to determine the associated risk factors of CAS. RESULTS: Multivariate logistic regression analysis revealed that two BPV metrics, the standard deviation of daytime systolic blood pressure (SSD) (OR: 1.587, 95%CI: 1.242-2.028), the difference between average daytime SBP and nighttime SBP (OR: 0.914, 95%CI: 0.855-0.977), as well as three clinical parameters (age, OR: 1.098, 95%CI: 1.034-1.167; smoking, OR: 4.072, 95%CI: 1.466-11.310, and fasting blood glucose, OR: 2.029, 95%CI: 1.407-2.928), were significant factors of CAS in essential hypertension patients. CONCLUSION: SSD, in combination with the ageing, smoking and FBG, has been identified as risk factors for CAS in patients with essential hypertension.

Arrestins contribute to amyloid beta-induced cell death via modulation of autophagy and the α7nAch receptor in SH-SY5Y cells.

Amyloid ß-protein (Aß) is believed to contribute to the development of Alzheimer's disease (AD). Here we showed that Aß25-35 rapidly caused activation of autophagy, subsequently leading to reduction of autophagy associated with cellular apoptosis. Further investigation revealed that the accumulation of ß-arrestin 1 (ARRB1) caused by Aß25-35 contributed to the induction of autophagic flux. The depletion of ARRB1 led to decreases in the expression of LC3B, Atg7, and Beclin-1, which are essential for the initiation of autophagy. ARRB1 depletion also reduced downstream ERK activity and promoted Aß25-35-induced cell death. As with ARRB1, transient upregulation of ARRB2 by Aß25-35 was observed after short treatment durations, whereas genetic reduction of ARRB2 caused a marked increase in the expression of the α7nAch receptor at the cell surface, which resulted in partial reversal of Aß25-35-induced cell death. Although expression of both ARRB1 and ARRB2 was reduced in serum from patients with AD, the levels of ARRB1 were much lower than those of ARRB2 in AD. Thus, our findings indicate that ARRB1/2 play different roles in Aß25-35 cytotoxicity, which may provide additional support for exploring the underlying molecular mechanism of AD.

Umbilical cord-derived mesenchymal stem cells reversed the suppressive deficiency of T regulatory cells from peripheral blood of patients with multiple sclerosis in a co-culture - a preliminary study.

The immunoregulatory function of T regulatory cells (Tregs) is impaired in multiple sclerosis (MS). Recent studies have shown that umbilical cord-derived mesenchymal stem cells (UC-MSCs) exert regulatory effect on the functions of immune cells. Thus, we investigated whether UC-MSCs could improve the impaired function of Tregs from MS patients. Co-cultures of UC-MSCs with PBMCs of MS patients were performed for 3 days. Flow cytometry was used to determine the frequency of Tregs. A cell proliferation assay was used to evaluate the suppressive capacity of Tregs. ELISA was conducted for cytokine analysis in the co-cultures. Our results showed that UC-MSCs significantly increased the frequency of CD4+CD25+CD127low/- Tregs in resting CD4+ T cells (p<0.01) from MS, accompanied by the significantly augmented production of cytokine prostaglandin E2, transforming growth factor (-ß1, and interleukin-10, along with a reduced interferon-γ production in these co-cultures (p<0.05 - 0.01). More importantly, UC-MSC-primed Tregs of MS patients significantly inhibited the proliferation of PHA-stimulated autologous and allogeneic CD4+CD25- T effector cells (Teffs) from MS patients and healthy individuals compared to non-UC-MSC-primed (naïve) Tregs from the same MS patients (p<0.01). Furthermore, no remarkable differences in suppressing the proliferation of PHA-stimulated CD4+CD25- Teffs was observed in UC-MSC-primed Tregs from MS patients and naïve Tregs from healthy subjects. The impaired suppressive function of Tregs from MS can be completely reversed in a co-culture by UC-MSC modulation. This report is the first to demonstrate that functional defects of Tregs in MS can be repaired in vitro using a simple UC-MSC priming approach.

Human umbilical cord-derived mesenchymal stem cells suppress proliferation of PHA-activated lymphocytes in vitro by inducing CD4(+)CD25(high)CD45RA(+) regulatory T cell production and modulating cytokine secretion.

Bone marrow-derived mesenchymal stem cells (MSCs) are promising candidate cells for therapeutic application in autoimmune diseases due to their immunomodulatory properties. Unused human umbilical cords (UC) offer an abundant and noninvasive source of MSCs without ethical issues and are emerging as a valuable alternative to bone marrow tissue for producing MSCs. We thus investigated the immunomodulation effect of umbilical cord-derived MSCs (UC-MSCs) on human peripheral blood mononuclear cells (PBMCs), T cells in particular, in a co-culture system. We found that UC-MSCs efficiently suppressed the proliferation of phytohaemagglutinin (PHA)-stimulated PBMCs (p<0.01). Kinetic analysis revealed that UC-MSCs primarily inhibited the division of generation 3 (G3) and 4 (G4) of PBMCs. In addition, UC-MSCs augmented the expression of CD127(+) and CD45RA(+) but reduced the expression of CD25(+) in PBMCs stimulated by PHA (p<0.05). Furthermore, UC-MSCs inhibited PHA-resulted increase in the frequency of CD4(+)CD25(+)CD127(low/-) Tregs significantly (p<0.01) but augmented PHA-resulted increase in the frequency of CD4(+)CD25(high)CD45RA(+) Tregs to about three times in PBMCs. The levels of anti-inflammatory cytokines, PEG2, TGF-ß, and IL-10 were greatly up-regulated, accompanied by a significant down-regulation of pro-inflammatory IFN-γ in the co-culture (p<0.01). Our results showed that UC-MSCs are able to suppress mitogen-induced PBMC activation and proliferation in vitro by altering T lymphocyte phenotypes, increasing the frequency of CD4(+)CD25(high)CD45RA(+) Tregs, and modulating the associated cytokine production. Further studies are warranted to investigate the therapeutic potential of UC-MSCs in immunologically-diseased conditions.