Association of cumulative low-density lipoprotein cholesterol exposure with vascular function.

BACKGROUND: The relationship between cumulative low-density lipoprotein cholesterol (LDL-C) exposure and progression of atherosclerosis remains uncertain. OBJECTIVE: The aim of this study was to determine the relationship between cumulative LDL-C level and flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID) and the presence of plaque in the common carotid artery (CCA). METHODS: This was a cross-sectional study. We measured FMD in 8208 subjects, NID in 1822 subjects, and CCA plaque in 591 subjects who were not taking lipid-lowering drugs. The subjects were divided into four groups based on cumulative LDL-C exposure: <4000 mg·year/dL, 4000-4999 mg·year/dL, 5000-5999 mg·year/dL, and ≥6000 mg·year/dL. RESULTS: The odds ratio of the lower quartile of FMD in the cholesterol-year-score <4000 mg·year/dL group was significantly higher than the odds ratios in the other groups. The odds ratio of the lower quartile of NID in the <4000 mg·year/dL group was significantly higher than the odds ratios in the 5000-5999 mg·year/dL and ≥6000 mg·year/dL groups. The odds ratio of the prevalence of CCA plaque in the <4000 mg·year/dL group was significantly higher than that in the ≥6000 mg·year/dL group. CONCLUSIONS: Endothelial dysfunction occurred from cumulative LDL-C exposure of 4000 mg·year/dL, vascular smooth muscle dysfunction occurred from cumulative LDL-C exposure of 5000 mg·year/dL, and prevalence of CCA plaque occurred from cumulative LDL-C exposure of 6000 mg·year/dL. CLINICAL TRIAL REGISTRY INFORMATION: http://www.umin.ac.jp (UMIN000012950, UMIN000012951, and UMIN000012952, UMIN000003409).

Exploring the mechanism of Danggui Buxue Decoction in regulating atherosclerotic disease network based on integrated pharmacological methods.

OBJECTIVE: To explore the mechanism of Danggui Buxue Decoction (DGBXD) in regulating Atherosclerosis (AS) network based on integrated pharmacological methods. METHODS: The active ingredients and targets of DGBXD are obtained from TCMSP database and ETCM. AS-related targets were collected from the Genecards and OMIM databases. The drug-disease protein interaction (PPI) networks were constructed by Cytoscape. Meanwhile, it was used to screen out densely interacting regions, namely clusters. Finally, Gene Ontology (GO) annotations are performed on the targets and genes in the cluster to obtain biological processes, and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations are performed on the targets of the PPI network to obtain signaling pathways. RESULTS: A total of 212 known targets, 265 potential targets and 229 AS genes were obtained. The 'DGBXD known-AS PPI network' and 'DGBXD-AS PPI Network' were constructed and analyzed. DGBXD can regulate inflammation, platelet activation, endothelial cell apoptosis, oxidative stress, lipid metabolism, vascular smooth muscle proliferation, angiogenesis, TNF, HIF-1, FoxO signaling pathway, etc. The experimental data showed that compared with the model group, the expressions of ICAM-1, VCAM-1, and interleukin (IL)-1ß protein and mRNA in the DGBXD group decreased (P<0.05). However, plasma IL-1ß, TNF-α, and MCP-1 in the DGBXD group were not significantly different from the model group (P>0.05). CONCLUSION: The mechanism of DGBXD in the treatment of AS may be related to the improvement of extracellular matrix (ECM) deposition in the blood vessel wall and the anti-vascular local inflammatory response, which may provide a reference for the study of the mechanism of DGBXD.

Human urinary kininogenase reduces the endothelial injury by inhibiting Pyk2/MCU pathway.

The injury of endothelial cells is one of the initiating factors in restenosis after endovascular treatment. Human urinary kallidinogenase (HUK) is a tissue kallikrein which is used for ischemia-reperfusion injury treatment. Studies have shown that HUK may be a potential therapeutic agent to prevent stenosis after vascular injury, however, the precise mechanisms have not been fully established. This study is to investigate whether HUK can protect endothelial cells after balloon injury or H2O2-induced endothelial cell damage through the proline-rich tyrosine kinase 2 (Pyk2)/mitochondrial calcium uniporter (MCU) pathway. Intimal hyperplasia, a decrease of pinocytotic vesicles and cell apoptosis were found in the common carotid artery balloon injury and H2O2-induced endothelial cell damage, Pyk2/MCU was also up-regulated in such pathological process. HUK could prevent these injuries partially via the bradykinin B2 receptor by inhibiting Pyk2/MCU pathway, which prevented the mitochondrial damage, maintained calcium balance, and eventually inhibited cell apoptosis. Furthermore, MCU expression was not markedly increased if Pyk2 was suppressed by shRNA technique in the H2O2 treatment group, and cell viability was significantly better than H2O2-treated only. In short, our results indicate that the Pyk2/MCU pathway is involved in endothelial injury induced by balloon injury or H2O2-induced endothelial cell damage. HUK plays an protective role by inhibiting the Pyk2/MCU pathway in the endothelial injury.

Corilagin ameliorates atherosclerosis by regulating MMP-1, -2, and -9 expression in vitro and in vivo.

Corilagin is a polyphenol has been identified anti-inflammatory properties. However, the anti-atherosclerotic effects of corilagin are not well understood. Here, we evaluated the anti-atherosclerotic effects and the underlying mechanisms of corilagin. We also verified whether corilagin can reverse atherosclerosis by regulating matrix metalloproteinase (MMP)-1, -2, and -9 in vitro and in vivo. An atherosclerosis model was established by feeding minipigs a high-fat diet combined with balloon injury, and the effects of different concentrations of corilagin on common carotid artery atherosclerosis in minipigs were monitored. Murine RAW264.7 macrophages were cultured and induced with oxidized low-density lipoprotein; fluorescence microscopy revealed the nuclear translocation of NF-κB. Furthermore, MMP-1, -2, and -9 expression in common carotid artery plaques and cellular models was detected by immunohistochemistry, western blotting, and RT-PCR. The pathological results suggested that the vascular intima of the model control group was significantly thickened, a large amount of collagen fibers was deposited, endothelial cells were damaged and detached, and plaque and foam cell formation occurred to varying degrees on the arterial wall, with lipid deposition. Corilagin treatment significantly reduced the degree of injury in the common carotid artery and decreased the number of lipid plaques and foam cells. Additionally, corilagin downregulated MMP-1, -2, and -9 expression in the common carotid artery plaques and cellular model. Moreover, corilagin significantly inhibited NF-κB nuclear translocation in vitro. Overall, corilagin exerted substantial therapeutic effects on experimental atherosclerotic minipigs via the downregulation of MMP-1, -2, and -9 expression.

Study of Neuroprotection by a Combination of the Biological Antioxidant (Eucalyptus Extract) and the Antihypertensive Drug Candesartan against Chronic Cerebral Ischemia in Rats.

Chronic cerebral ischemia with a notable long-term cessation of blood supply to the brain tissues leads to sensorimotor defects and short- and long-term memory problems. Neuroprotective agents are used in an attempt to save ischemic neurons from necrosis and apoptosis, such as the antioxidant agent Eucalyptus. Numerous studies have demonstrated the involvement of the renin-angiotensin system in the initiation and progression of cardiovascular and neurodegenerative diseases. Candesartan is a drug that acts as an angiotensin II receptor 1 blocker. We established a rat model exhibiting sensorimotor and cognitive impairments due to chronic cerebral ischemia induced by the ligation of the right common carotid artery. Wistar male rats were randomly divided into five groups: Sham group, Untreated Ligated group, Ischemic group treated with Eucalyptus (500 mg/kg), Ischemic group treated with Candesartan (0.5 mg/kg), and Ischemic group treated with a combination of Eucalyptus and Candesartan. To evaluate the sensorimotor disorders, we performed the beam balance test, the beam walking test, and the modified sticky test. Moreover, the object recognition test and the Morris water maze test were performed to assess the memory disorders of the rats. The infarct rat brain regions were subsequently stained using the triphenyltetrazolium chloride staining technique. The rats in the Sham group had normal sensorimotor and cognitive functions without the appearance of microscopic ischemic brain lesions. In parallel, the untreated Ischemic group showed severe impaired neurological functions with the presence of considerable brain infarctions. The treatment of the Ischemic group with a combination of both Eucalyptus and Candesartan was more efficient in improving the sensorimotor and cognitive deficits (p < 0.001) than the treatment with Eucalyptus or Candesartan alone (p < 0.05), by the comparison to the non-treated Ischemic group. Our study shows that the combination of Eucalyptus and Candesartan could decrease ischemic brain injury and improve neurological outcomes.

Methotrexate Therapy Promotes Cell Coverage and Stability in in-Stent Neointima.

PURPOSE: Anti-proliferative drugs released from drug-eluting stents delay cell coverage and vascular healing, which increases the risk of late stent thrombosis. We assessed the potential effects of systemic methotrexate (MTX) on cell coverage, vascular healing and inflammation activation in vivo and in vitro. METHODS: We applied MTX in the right common carotid artery in a rabbit stenting model to determine the impact on cell coverage and inflammation activation using a serial optical coherence tomography (OCT) analysis and elucidated the molecular mechanism of MTX in human umbilical vein endothelial cells (HUVECs). RESULTS: Low-dose MTX promoted the development of cell coverage and vascular healing, which was associated with fewer uncovered struts (%) and cross-sections with any uncovered struts (%) at 4 weeks of stenting. The MTX group also exhibited lower rates of heterogeneity, microvessels and per-strut low-signal-intensity layers, indicating neointimal instability at 12 weeks of stenting. In vitro, low-dose MTX strongly inhibited HUVEC apoptosis, promoted proliferation and inhibited inflammatory activation by targeting the phosphoinositide 3-kinase (PI3K)/AKT signalling pathway. CONCLUSION: Low-dose MTX may be a key means of promoting early cell coverage via the inhibition of the inflammatory response and stability of neointima by targeting inflammatory pathways after stent implantation.

Rabbit Elastase Aneurysm: Imaging and Histology Correlates for Inflammation and Healing.

OBJECTIVE: Aneurysmal subarachnoid hemorrhage remains a devastating event with poorly understood pathophysiology. Previous studies have suggested that aneurysm wall inflammation may play a part in the development and potential rupture of aneurysms. The rabbit elastase aneurysm model is a well-established model, which produces aneurysms closely mimicking human cerebral aneurysms in flow dynamics and histopathology. The primary aim of this study was to correlate inflammatory changes after aneurysm formation using sequential vessel wall imaging with histopathologic analysis. A secondary aim was to evaluate the potential effect of gender and anti-inflammatory treatment with aspirin on this inflammatory response. METHODS: Twenty-seven New Zealand rabbits underwent surgery to create an aneurysm using elastase infusion at the right common carotid artery origin. Vessel wall imaging and histopathologic analysis was obtained at different time points after aneurysm creation. The rabbits were also randomized by gender and to treatment groups with or without aspirin. RESULTS: Histopathologic analysis revealed 3 distinct phases after aneurysm formation. These phases were an initial inflammatory phase, followed by a regeneration phase, and finally a connective tissue deposition phase. Vessel wall imaging demonstrated 2 distinct imaging patterns. No appreciable differences were seen in histology or imaging when comparing gender or treatment with aspirin. CONCLUSIONS: Inflammatory changes induced by the rabbit elastase aneurysm model can be correlated with histopathologic findings and observed on noninvasive vessel wall imaging. This may provide a method to study the inflammatory pathway as it pertains to aneurysmal development and subsequent rupture.

18F-Fluorodeoxyglucose-Positron Emission Tomography Imaging Detects Response to Therapeutic Intervention and Plaque Vulnerability in a Murine Model of Advanced Atherosclerotic Disease-Brief Report.

OBJECTIVE: This study sought to determine whether 18F-fluorodeoxyglucose-positron emission tomography/computed tomography could be applied to a murine model of advanced atherosclerotic plaque vulnerability to detect response to therapeutic intervention and changes in lesion stability. Approach and Results: To analyze plaques susceptible to rupture, we fed ApoE-/- mice a high-fat diet and induced vulnerable lesions by cast placement over the carotid artery. After 9 weeks of treatment with orthogonal therapeutic agents (including lipid-lowering and proefferocytic therapies), we assessed vascular inflammation and several features of plaque vulnerability by 18F-fluorodeoxyglucose-positron emission tomography/computed tomography and histopathology, respectively. We observed that 18F-fluorodeoxyglucose-positron emission tomography/computed tomography had the capacity to resolve histopathologically proven changes in plaque stability after treatment. Moreover, mean target-to-background ratios correlated with multiple characteristics of lesion instability, including the corrected vulnerability index. CONCLUSIONS: These results suggest that the application of noninvasive 18F-fluorodeoxyglucose-positron emission tomography/computed tomography to a murine model can allow for the identification of vulnerable atherosclerotic plaques and their response to therapeutic intervention. This approach may prove useful as a drug discovery and prioritization method.

Resveratrol Inhibits Neointimal Growth after Arterial Injury in High-Fat-Fed Rodents: The Roles of SIRT1 and AMPK.

We have shown that both insulin and resveratrol (RSV) decrease neointimal hyperplasia in chow-fed rodents via mechanisms that are in part overlapping and involve the activation of endothelial nitric oxide synthase (eNOS). However, this vasculoprotective effect of insulin is abolished in high-fat-fed insulin-resistant rats. Since RSV, in addition to increasing insulin sensitivity, can activate eNOS via pathways that are independent of insulin signaling, such as the activation of sirtuin 1 (SIRT1) and AMP-activated kinase (AMPK), we speculated that unlike insulin, the vasculoprotective effect of RSV would be retained in high-fat-fed rats. We found that high-fat feeding decreased insulin sensitivity and increased neointimal area and that RSV improved insulin sensitivity (p < 0.05) and decreased neointimal area in high-fat-fed rats (p < 0.05). We investigated the role of SIRT1 in the effect of RSV using two genetic mouse models. We found that RSV decreased neointimal area in high-fat-fed wild-type mice (p < 0.05), an effect that was retained in mice with catalytically inactive SIRT1 (p < 0.05) and in heterozygous SIRT1-null mice. In contrast, the effect of RSV was abolished in AMKPα2-null mice. Thus, RSV decreased neointimal hyperplasia after arterial injury in both high-fat-fed rats and mice, an effect likely not mediated by SIRT1 but by AMPKα2.

Ruxolitinib attenuates intimal hyperplasia via inhibiting JAK2/STAT3 signaling pathway activation induced by PDGF-BB in vascular smooth muscle cells.

BACKGROUND: Cardiovascular diseases are associated with proliferation and phenotypic switch. Platelet-derived growth factor-BB (PDGF-BB) is a major initiating factor for proliferative vascular diseases, such as neointimal lesion formation, restenosis after angioplasty, and atherosclerosis. Ruxolitinib, a potent Janus kinase (JAK) 1 and 2 inhibitor, has been reported to significantly block the proliferation-related signaling pathway of JAK2/signal transducers and activators of transcription 3 (STAT3) and harbor a broad spectrum of anti-cancer activities, including proliferation inhibition, apoptosis induction, and anti-inflammation. However, the role of ruxolitinib in regulating PDGF-BB-induced VSMC proliferation remains to be elucidated. Thus, this study investigates the role of ruxolitinib in regulating PDGF-BB-induced VSMC proliferation and its underlying mechanisms. METHODS: In vivo, the medial thickness of the carotid artery was evaluated using a mouse carotid ligation model, ruxolitinib was administered orally to the mice every other day, and the mice were euthanized on day 28 to evaluate the therapeutic effects of ruxolitinib. Cell proliferation markers were measured using real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting. In vitro, VSMCs were treated with ruxolitinib with or without PDGF-BB at an indicated time and concentration. Cell proliferation and apoptosis were measured using Cell Counting Kit-8 assay, MTS assays and flow cytometry. The JAK2/STAT3 signaling pathway involved in the effects of ruxolitinib on VSMCs was detected by western blotting with the specific pathway inhibitor AG490. RESULTS: In vivo, ruxolitinib significantly decreased the ratio-of-intima ratio (I/M ratio) by inhibiting the expression of PCNA and cyclinD1 (p <0.05). In vitro, ruxolitinib inhibited PDGF-BB-induced VSMC proliferation compared with the PDGF-BB treatment group (p <0.05). In addition, ruxolitinib inhibited the PDGF-BB-induced activation of the JAK2/STAT3 signaling pathway and decreased the expression of proliferation related-proteins cyclinD1 and PCNA in VSMCs (p <0.05). CONCLUSION: Our findings suggest that ruxolitinib inhibits VSMC proliferation in vivo and in vitro by suppressing the activation of the JAK2/STAT3 signaling pathway. Therefore, ruxolitinib has a therapeutic potential for proliferative vascular diseases.

Moderate Alcohol Consumption Targets S100ß+ Vascular Stem Cells and Attenuates Injury-Induced Neointimal Hyperplasia.

BACKGROUND: Stem cells present in the vessel wall may be triggered in response to injurious stimuli to undergo differentiation and contribute to vascular disease development. Our aim was to determine the effect of moderate alcohol (EtOH) exposure on the expansion and differentiation of S100 calcium-binding protein B positive (S100ß+ ) resident vascular stem cells and their contribution to pathologic vessel remodeling in a mouse model of arteriosclerosis. METHODS AND RESULTS: Lineage tracing analysis of S100ß+ cells was performed in male and female S100ß-eGFP/Cre/ERT2-dTomato transgenic mice treated daily with or without EtOH by oral gavage (peak BAC: 15 mM or 0.07%) following left common carotid artery ligation for 14 days. Carotid arteries (ligated or sham-operated) were harvested for morphological analysis and confocal assessment of fluorescent-tagged S100 ß + cells in FFPE carotid cross sections. Ligation-induced carotid remodeling was more robust in males than in females. EtOH-gavaged mice had less adventitial thickening and markedly reduced neointimal formation compared to controls, with a more pronounced inhibitory effect in males compared to females. There was significant expansion of S100ß+ -marked cells in vessels postligation, primarily in the neointimal compartment. EtOH treatment reduced the fraction of S100ß+ cells in carotid cross sections, concomitant with attenuated remodeling. In vitro, EtOH attenuated Sonic Hedgehog-stimulated myogenic differentiation (as evidenced by reduced calponin and myosin heavy chain expression) of isolated murine S100ß+ vascular stem cells. CONCLUSIONS: These data highlight resident vascular S100ß+ stem cells as a novel target population for alcohol and suggest that regulation of these progenitors in adult arteries, particularly in males, may be an important mechanism contributing to the antiatherogenic effects of moderate alcohol consumption.

Ginsenoside Rg1 prevents vascular intimal hyperplasia involved by SDF-1α/CXCR4, SCF/c-kit and FKN/CX3CR1 axes in a rat balloon injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Panax ginseng C. A. Mey. is a traditional tonic that has been used for thousands of years, and has positive effects on vascular diseases. Ginsenoside Rg1 (GS-Rg1) is one of the active ingredients of Panax ginseng C. A. Mey. and has been shown to have beneficial effects against ischemia/reperfusion injury. Our previously study has found that GS-Rg1 can mobilize bone marrow stem cells and inhibit vascular smooth muscle proliferation and phenotype transformation. However, pharmacological effects and mechanism of GS-Rg1 in inhibiting intimal hyperplasia is still unknown. AIM OF THE STUDY: This study was aimed to investigate whether GS-Rg1 prevented vascular intimal hyperplasia, and the involvement of stromal cell-derived factor-1α (SDF-1α)/CXCR4, stem cell factor (SCF)/c-kit and fractalkine (FKN)/CX3CR1 axes. MATERIALS AND METHODS: Rats were operated with carotid artery balloon injury. The treatment groups were injected with 4, 8 and 16 mg/kg of GS-Rg1 for 14 days. The degree of intimal hyperplasia was evaluated by histopathological examination. The expression of α-SMA (α-smooth muscle actin) and CD133 were detected by double-label immunofluorescence. Serum levels of SDF-1α, SCF and soluble FKN (sFKN) were detected by enzyme linked immunosorbent assay (ELISA). The protein expressions of SCF, SDF-1α and FKN, as well as the receptors c-kit, CXC chemokine receptor type 4 (CXCR4) and CX3C chemokine receptor type 1 (CX3CR1) were detected by immunochemistry. RESULTS: GS-Rg1 reduced intimal hyperplasia by evidence of the values of NIA, the ratio of NIA/MA, and the ratio of NIA/IELA and the ratio of NIA/LA, especially in 16 mg/kg group. Furthermore, GS-Rg1 8 mg/kg group and 16 mg/kg group decreased the protein expressions of the SDF-1α/CXCR4, SCF/c-kit and FKN/CX3CR1 axes in neointima, meanwhile GS-Rg1 8 mg/kg group and 16 mg/kg group also attenuated the expressions of SDF-1α, SCF and sFKN in serum. In addition, the expression of α-SMA and CD133 marked smooth muscle progenitor cells (SMPCs) was decreased after GS-Rg1 treatment. CONCLUSIONS: GS-Rg1 has a positive effect on inhibiting vascular intimal hyperplasia, and the underlying mechanism is related to inhibitory expression of SDF-1α/CXCR4, SCF/c-kit and FKN/CX3CR1 axes.

Vasoreactivity of the Murine External Jugular Vein and Carotid Artery.

INTRODUCTION: Impaired venous reactivity has potential to contribute to clinically significant pathologies such as arteriovenous fistula (AVF) maturation failure. Vascular segments commonly used in murine preclinical models of AVF include the carotid artery and external jugular vein. Detailed descriptions of isometric procedures to evaluate function of murine external jugular vein ex vivo have not been previously published. OBJECTIVE: To establish isometric procedures to measure naive murine external jugular vein reactivity ex vivo. METHODS: Vasomotor responses of external jugular veins and ipsilateral common carotid arteries from C57BL/6 mice were evaluated using isometric tension procedures. RESULTS: External jugular veins developed tension (p < 0.05) to potassium chloride and U-46619, but not to phenylephrine, whereas common carotid arteries responded to all 3 agents (p < 0.05). While maximal responses to acetylcholine (ACh) were similar between the venous and arterial segments, the dose required to achieve this value was lower (p < 0.05) in the artery versus vein. Nitric oxide synthase inhibition attenuated (p < 0.05) but did not abolish ACh-evoked vasorelaxation in both vascular segments, whereas cyclooxygenase blockade had no effect. Endothelium-independent vasorelaxation to sodium nitroprusside was similar in the artery and vein. CONCLUSION: Vasorelaxation and vasocontraction can be reliably assessed in the external jugular vein in C57BL/6 mice using isometric procedures.

Changes in carotid stiffness in patients with familial hypercholesterolemia treated with Evolocumab®: A prospective cohort study.

BACKGROUND AND AIM: Protein convertase subtilisin kexin type 9 (PCSK-9) inhibitors demonstrated efficacy in cholesterol reduction and in the prevention of cardiovascular events. We evaluated changes in lipid profile and carotid stiffness in patients with familial hypercholesterolemia during 12 weeks of treatment with a PCSK-9 inhibitor, Evolocumab®. METHODS AND RESULTS: Patients with familial hypercholesterolemia starting a treatment with Evolocumab® were included. Total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), small dense LDL (assessed by LDL score) and carotid stiffness were evaluated before starting treatment with Evolocumab® and during 12 weeks of treatment. Twenty-five subjects were enrolled (52% males, mean age 51.5 years). TC and LDL-C were reduced of 38% and 52%, respectively during treatment, with LDL score reduced of 46.1%. In parallel, carotid stiffness changed from 8.8 (IQR: 7.0-10.4) m/sec to 6.6 (IQR: 5.4-7.5) m/sec, corresponding to a median change of 21.4% (p < 0.001), with a significant increase in carotid distensibility (from 12.1, IQR: 8.73-19.3 kPA-1 × 10-3 at T0 to 21.8, IQR: 16.6-31.8 kPA-1 × 10-3 at T12w) corresponding to a median change of 62.8% (p < 0.001). A multivariate analysis showed that changes in LDL score were independently associated with changes in carotid stiffness (ß = 0.429, p = 0.041). CONCLUSION: Small dense LDL reduction, as assessed by LDL score, is associated with changes in carotid stiffness in patients with familial hypercholesterolemia treated with Evolocumab®.

Donepezil down-regulates propionylation, 2-hydroxyisobutyrylation, butyrylation, succinylation, and crotonylation in the brain of bilateral common carotid artery occlusion-induced vascular dementia rats.

Vascular dementia (VaD), caused by stroke or small vessel disease, is the second-most common type of dementia after Alzheimer's disease (AD). Donepezil is an acetylcholinesterase inhibitor that is currently used in patients with mild to moderate AD, and has recently been shown to improve cognitive performance in patients with VaD. In this study, we evaluated the effects of donepezil on VaD, and investigated the underlying molecular mechanisms of action. VaD was established by ligation of the bilateral common carotid artery occlusion (BCCAO). Executive function was tested by the Morris water maze (MWM) test and the attentional set shifting task (ASST). Our results showed that donepezil improved executive dysfunction and cognitive flexibility in BCCAO rats. In addition, we showed that donepezil treatment decreased the level of Aß1-42 in BCCAO rats by enzyme-linked immunosorbent assay. Post-translational modifications (PTMs) are known to be critical mechanisms in the regulation of various cellular processes. Furthermore, PTMs have been linked to the central nervous system, which highlights the importance of PTMs in neurodegenerative diseases. In this study, we used western blot analysis to identify several novel PTMs in the hippocampus of BCCAO rats that were treated with or without donepezil. The data revealed that lysine propionylation, 2-hydroxyisobutyrylation, butyrylation, succinylation, and crotonylation were elevated in the hippocampus of BCCAO rats when compared to sham rats. This increase was abolished by donepezil treatment. Taken together, we speculate that donepezil treatment improves cognitive function in our animal model of VaD, possibly by reducing aberrant acyl-PTMs.

Pathogenic Mechanisms of a Stroke-like attack Elicited by Epidural Steroid Injection Therapy.

BACKGROUND: The pathogenic mechanisms involved in a disastrous scenario, following epidural steroid injections (ESI), remain unclarified. Intra-arterial injection of steroids with needlepenetrating vascular injury would be the culprit, as particulate medicine elicits a brain or spinal cord stroke-like attack. METHODS: On the other hand, the limited experimental approaches simulating an accidental steroid intra-arterial injection for ESI conflicted in their results: hemorrhage vs. ischemia. RESULTS: This article dissects the potential pathogenic mechanisms at a neurovascular unit. Noticeably, a schematic representation provides an explanation of how emboli formed by particulate steroids elicit either hemorrhagic, or ischemic lesion. CONCLUSION: In addition, the development of a rat model with intravertebral artery steroid injection is a proposal to address the unmet need in evaluating steroids and vascular injury in ESI.

Progesterone Protects Prefrontal Cortex in Rat Model of Permanent Bilateral Common Carotid Occlusion via Progesterone Receptors and Akt/Erk/eNOS.

Sustained activation of pro-apoptotic signaling due to a sudden and prolonged disturbance of cerebral blood circulation governs the neurodegenerative processes in prefrontal cortex (PFC) of rats whose common carotid arteries are permanently occluded. The adequate neuroprotective therapy should minimize the activation of toxicity pathways and increase the activity of endogenous protective mechanisms. Several neuroprotectants have been proposed, including progesterone (P4). However, the underlying mechanism of its action in PFC following permanent bilateral occlusion of common carotid arteries is not completely investigated. We, thus herein, tested the impact of post-ischemic P4 treatment (1.7 mg/kg for seven consecutive days) on previously reported aberrant neuronal morphology and amount of DNA fragmentation, as well as the expression of progesterone receptors along with the key elements of Akt/Erk/eNOS signal transduction pathway (Bax, Bcl-2, cytochrome C, caspase 3, PARP, and the level of nitric oxide). The obtained results indicate that potential amelioration of histological changes in PFC might be associated with the absence of activation of Bax/caspase 3 signaling cascade and the decline of DNA fragmentation. The study also provides the evidence that P4 treatment in repeated regiment of administration might be effective in neuronal protection against ischemic insult due to re-establishment of the compromised action of Akt/Erk/eNOS-mediated signaling pathway and the upregulation of progesterone receptors.

Three-Dimensional Contractile Mechanics of Artery Accounting for Curl of Axial Strip Sectioned from Vessel Wall.

PURPOSE: It is well known that a sliced ring of arterial wall opens by a radial cut. An axial strip sectioned from arterial wall also curls into an arc. These phenomena imply that there exist residual strains in the circumferential and axial directions. How much do the axial residual strains affect the stress distributions of arterial wall? The aim of the present study is to know stress distributions of arterial wall with the residual strains under the passive and constricted conditions. METHODS: We analyzed the stress distributions under passive and constricted conditions with considering a Riemannian stress-free configuration. In the analysis, we used strain energy functions to describe the passive and active mechanical properties of artery. RESULTS: The present study provided distributions of stretch ratio with reference to the stress-free state (Riemannian stress-free configuration) and stress with and without the curl of axial strip of a homogenous cylindrical arterial model under the passive and constricted smooth muscle conditions. The circumferential and axial stresses with activated smooth muscle (noradrenaline 10-5 M) at the intraluminal pressure 16 kPa and the axial stretch ratio 1.5 with reference to the unloaded vessel decreased by 3.5 and 13.8% at the inner surface with considering the axial residual strain, respectively. CONCLUSIONS: We have shown that the Riemannian stress-free configuration is appropriate tool to analyze stress distributions of arterial wall under passive and activated conditions with the residual stresses.

Molecular Alterations and Effects of Acute Dehydroepiandrosterone Treatment Following Brief Bilateral Common Carotid Artery Occlusion: Relevance to Transient Ischemic Attack.

Transient ischemic attack (TIA) represents brief neurological dysfunction of vascular origin without detectable infarction. Despite major clinical relevance characterization of post-TIA molecular changes using appropriate experimental model is lacking and no therapeutic agent has been established yet. Neurosteroid dehydroepiandrosterone (DHEA) arose as one of the candidates for cerebral ischemia treatment but its effects on TIA-like condition remain unknown. Seeking an animal model applicable for investigation of molecular alterations in mild ischemic conditions such as TIA, 15-min bilateral common carotid artery occlusion with 24-h reperfusion was performed to induce ischemia/ reperfusion (I/R) injury in adult male Wistar rats. Additionally, effects of 4-h post-operative DHEA treatment (20 mg/kg) were investigated in physiological and I/R conditions in hippocampus (HIP) and prefrontal cortex (PFC). The study revealed absence of sensorimotor deficits, cerebral infarcts and neurodegeneration along with preserved HIP and PFC overall neuronal morphology and unaltered malondialdehyde and reduced glutathione level following I/R and/or DHEA treatment. I/R induced nitric oxide burst in HIP and PFC was accompanied with increased neuronal nitric oxide synthase protein level exclusively in HIP. DHEA had no effects in physiological conditions, while increase of Bax/Bcl2 ratio and dissipation of mitochondrial membrane potential in treated I/R group suggested DHEA-mediated exacerbation of post-ischemic changes that might lead to pro-apoptotic events in HIP. Interestingly, DHEA restored I/R-induced NO to the control level in PFC. Obtained results indicated that I/R may serve as an appropriate model for investigation of molecular changes and treatment outcome following mild ischemic conditions such as TIA.

Minoxidil versus placebo in the treatment of arterial wall hypertrophy in children with Williams Beuren Syndrome: a randomized controlled trial.

BACKGROUND: Insufficient elastin synthesis leads to vascular complications and arterial hypertension in children with Williams-Beuren syndrome. Restoring sufficient quantity of elastin should then result in prevention or inhibition of vascular malformations and improvement in arterial blood pressure. METHODS: The aim of this study was to assess the efficacy and safety of minoxidil on Intima Media Thickness (IMT) on the right common carotid artery after twelve-month treatment in patient with Williams-Beuren syndrome. We performed a randomized placebo controlled double blind trial. All participants were treated for 12 months and followed for 18 months. The principal outcome was assessed by an independent adjudication committee blinded to the allocated treatment groups. RESULTS: The principal outcome was available for 9 patients in the placebo group and 8 patients in the minoxidil group. After 12-month treatment, the IMT in the minoxidil group increased by 0.03 mm (95% CI -0.002, 0.06) compared with 0.01 mm (95%CI - 0.02, 0.04 mm) in the placebo group (p = 0.4). Two serious adverse events unrelated to the treatment occurred, one in the minoxidil and 1 in the placebo group. After 18 months, the IMT increased by 0.07 mm (95% CI 0.04, 0.10 mm) in the minoxidil compared with 0.01 mm (95% CI -0.02, 0.04 mm) in the placebo group (p = 0.008). CONCLUSION: Our results suggest a slight increase after 12 and 18-month follow-up in IMT. More understanding of the biological changes induced by minoxidil should better explain its potential role on elastogenesis in Williams-Beuren syndrome. TRIALS REGISTRATION: US National Institutes of Health Clinical Trial Register (NCT00876200). Registered 3 April 2009 (retrospectively registered).