Jieqing Wan

Surgical management of large solid hemangioblastomas of the posterior fossa

From January 2000 to January 2009, 15 patients presented with large solid hemangioblastomas of the posterior fossa; eight of these patients were also diagnosed with von Hippel-Lindau (VHL) disease. Diagnostic imaging showed large vascular lesions. All 15 patients underwent surgery through a suboccipital ipsilateral, modified far-lateral, suboccipital midline or suboccipital supracerebellar approach. Preoperative embolization was attempted in seven patients. Complete removal of the tumor was performed in all patients. An overall neurological improvement was observed in 11 of the 15 patients, corresponding to 61.5%. During follow-up, six patients, all with VHL disease, developed recurrence. Two patients died of renal cell carcinoma after 1 year. Our favorable outcomes suggest that surgical resection is the optimal treatment for patients with large solid hemangioblastomas of the posterior fossa. With improved microsurgical techniques and a better understanding of the vascular pattern of this type of tumor, total microsurgical removal can be performed with low mortality.

Role of intraoperative microvascular Doppler in the microsurgical management of intracranial aneurysms

The outcome of surgical treatment of intracranial aneurysms may be influenced by incomplete exclusion of the aneurysm or stenosis of the parent vessels. The goal of this study was to evaluate the usefulness and reliability of intraoperative microvascular Doppler (IMD) in guiding optimal clip placement in aneurysm surgery.

Global transcriptomic study of atherosclerosis development in rats

Atherosclerosis is a chronic disease of the arterial wall and a leading cause of death worldwide. Though the pathophysiology of atherosclerotic lesion formation has been studied, we still lack evidence of the global changes in the artery during atherosclerosis. In this report, we induced atherosclerosis in rats and conducted GeneChip analysis on carotid arteries with or without plaque formation. We found that molecular pathways underlying plaque formation in atherosclerosis were related to immune response, angiogenesis, cell proliferation, apoptosis and hypoxic microenvironments, suggesting that the pathophysiology of atherosclerosis is varied. In addition, we showed that three lncRNAs, GAS5, SNHG6 and Zfas1, were significantly increased in the plaque of atherosclerosis patients compared to normal people. A complex interaction of mRNA and lncRNA was identified in atherosclerosis. Our results provide a global transcriptomic network of atherosclerosis development in rats and possible targets that could lead to new clinical applications in the future.

MiR-377 Regulates Inflammation and Angiogenesis in Rats After Cerebral Ischemic Injury: MiR-377 REGULATES INFLAMMATION AND ANGIOGENESIS IN RATS

Ischemic stroke is the leading cause of disabilities worldwide. MicroRNA‐377 (miR‐377) plays important roles in ischemic injury. The present study focused on the mechanisms of miR‐377 in protecting ischemic brain injury in rats. Cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in rats. Primary rat microglial cells and brain microvascular endothelial cells (BMECs) were exposed to oxygen‐glucose deprivation (OGD). The concentrations of cytokines (TNF‐α, IL‐1β, IL‐6, IFN‐γ, TGF‐β, MMP2, COX2, and iNOS) in the culture medium were measured by specific ELISA. Tube formation assay was for the in vitro study of angiogenesis. Luciferase reporter assay was performed to confirm whether VEGF and EGR2 were direct targets of miR‐377. The MCAO rats were intracerebroventricular (ICV) injection of miR‐377 inhibitor to assess its protective effects in vivo. MiR‐377 levels were decreased in the rat brain tissues at 1, 3, and 7 d after MCAO. Both microglia cells and BMECs under OGD showed markedly lower expression levels of miR‐377 while higher expression levels of EGR2 and VEGF compared to those under normoxia conditions. Knockdown of miR‐377 inhibited microglial activation and the release of pro‐inflammatory cytokines after OGD. Suppression of miR‐377 promoted the capillary‐like tube formation and cell proliferation and migration of BMECs. The anti‐inflammation effect of EGR2 and the angiogenesis effect of VEGF were regulated by miR‐377 after OGD. Inhibition of miR‐377 decreased cerebral infarct volume and suppressed cerebral inflammation but promoted angiogenesis in MCAO rats. Knockdown of miR‐377 lessened the ischemic brain injury through promoting angiogenesis and suppressing cerebral inflammation. J. Cell. Biochem. 119: 327–337, 2018.

Neurocognitive Improvement After Carotid Artery Stenting in Patients With Chronic Internal Carotid Artery Occlusion A Prospective, Controlled, Single-Center Study

Symptomatic internal carotid artery (ICA) occlusion with hemodynamic impairment remains a dismal disease when untreated. In this prospective, single-center, controlled study, we investigated the feasibility, safety, and long-term outcome of stenting by endovascular recanalization for patients with chronic ICA occlusion. Forty patients with symptomatic chronically occluded ICA were assigned to receive endovascular recanalization (group A, n = 18) or conservative management (group B, n = 22). The primary end point was 100% complete recanalization of the primary occlusion at 60 minutes, and secondary end points were improvement in neurologic function and cognitive function. Patients in the 2 groups were comparable in demographic and baseline characteristics. Successful recanalization was achieved in 88.9% (16 of 18) of patients with the restoration of Thrombolysis in Myocardial Ischemia/Thrombolysis in Cerebral Ischemia 2 or 3 flow. There was no procedural or new cerebral ischemic event. Improvement in brain perfusion was observed in 12 (12 of 18, 75%) patients on single-photon emission computed tomography. Improvement in neurologic function defined as a reduction of ≥4 points on the National Institutes of Health Stroke Scale (NIHSS) at 6 months was observed in group A (baseline, 6.83 ± 3.01 vs 6 months, 2.61 ± 1.20; P < .01) and group B (baseline, 6.05 ± 2.75 vs 6 months, 4.77 ± 1.69; P < .05). A significant difference in NIHSS scores was noted between group A and B at 1, 3, and 6 months (P < .05 or .001). Improvement in cognitive function defined as an increase of ≥8 on the Montreal Cognitive Assessment (MoCA) was observed in group A at 3 and 6 months (baseline, 14.67 ± 3.56 vs 3 months, 24.17 ± 3.55 and 6 months, 24.72 ± 2.85; P < .01). Significant improvement in MoCA was also observed in group B (P < .01). Furthermore, a significant difference in MoCA scores was noted between group A and B at 1, 3, and 6 months (P < .05 or .001). Endovascular recanalization is feasible and safe for patients with symptomatic chronic carotid artery occlusion. Successful carotid artery stenting can improve neurological function and global cognitive function than nonrevascularization.

Potassium channel dysfunction in neurons and astrocytes in Huntington's disease

Huntingtons disease (HD) is a late‐onset fatal neurodegenerative disease, characterized by progressive movement disorders, psychiatric symptoms, and cognitive impairment. The cytosine‐adenine‐guanine (CAG) triplet expansion encoding glutamine present in the protein huntingtin (Htt), produces widespread neuronal and glial pathology. Mutant huntingtin (mHtt) nuclear aggregates are the primary cause of cortical and striatal neuron degeneration, neuronal inflammation, apoptosis and eventual cell loss. The precise mechanisms underlying the pathogenesis of neurodegeneration in HD remain poorly understood and HD patients have no current cure. Potassium channels are widely expressed in most cell types. In neurons, they play a crucial role in setting the resting membrane potential, mediating the rapid repolarization phase of the action potential and controlling sub‐threshold oscillations of membrane potentials. In glial cells, their major contributions are maintaining the resting membrane potential and buffering extracellular K+. Thus, potassium channels have an essential function in both physiological and pathological brain conditions. This review summarizes recent progress on potassium channels involved in the pathology of HD by using different HD mouse models. Exploring the dysfunction of potassium channels in the brain illustrates new approaches for targeting this channel for the treatment of HD.

Atorvastatin increases endothelial progenitor cells in balloon-injured mouse carotid artery

Here we aimed to investigate the effects of atorvastatin on accelerated reendothelialization after carotid balloon injury. A mouse model of carotid arterial injury was established, followed by intragastric administration of atorvastatin at a dose of 0.6 mg·(kg body mass)(-1)·d(-1). Pathological sections of carotid artery stained with hematoxylin and eosin were observed under light microscopy. Expression levels of eNOS mRNA and protein were detected with real-time quantitative PCR and Western blot analysis, respectively. Proliferation and differentiation of endothelial progenitor cells (EPCs) were observed after treatment, in vitro. Reendothelialization appeared on the neovascular surface, while intimal hyperplasia was inhibited after treatment with atorvastatin. Numbers of CD31-positive cells increased after atorvastatin treatment, as did the number of leucocyte antigen positive cells. The expression of cell markers, such as CD34, eNOS, and VEGF-R, were higher in the atorvastatin-treated group of mononuclear cells. EPC numbers increased with the concentration of atorvastatin. The expression of eNOS mRNA was reduced in the mice with carotid artery injury that were treated with normal saline. The expression levels of eNOS protein were increased in atorvastatin treatment group. In conclusion, atorvastatin stimulates EPCs to differentiate into endothelial cells and promotes the repair of carotid arterial injury.

Expression of nerve growth factor carried by pseudotyped lentivirus improves neuron survival and cognitive functional recovery of post-ischemia in rats

Nerve growth factor (NGF) has been reported to prevent neuronal damage and contributes to the functional recovery in animal brain injury models and human ischemic disease as well. We aimed to investigate a potential therapeutic effect of NGF gene treatment in ischemic stroke and to estimate the functional recovery both at the cellular and cognitive levels in an ischemia rat model.

Legumain suppresses OxLDL-induced macrophage apoptosis through enhancement of the autophagy pathway

OBJECTIVE Autophagy plays a prominent role in the pathogenesis of plaques formation and progression of atherosclerosis (AS). The cysteine protease legumain is known to participate in atherogenesis, but its function and underlying mechanism in AS macrophages remain unclear. METHODS The expressions of legumain in plaques isolated from AS patients and in macrophages stimulated with oxLDL were examined. Moreover, we effectively altered legumain expression in macrophages to characterize the effect of legumain on oxLDL-induced macrophage apoptosis. The expression of apoptotic and autophagic factors was analysed. RESULTS Legumain was present in plaques, and its expression was upregulated in macrophages treated with oxLDL. Suppressing legumain significantly increased oxLDL-induced macrophage apoptosis and the expression of caspase 3, caspase 9 and Bax. However, legumain overexpression decreased macrophage apoptosis upon oxLDL exposure and the levels of caspase 3, caspase 9 and Bax. In addition, recombinant legumain protein suppressed macrophage apoptosis. Biochemical experiments revealed that legumain deficiency decreased the levels of Beclin1 and LC3, whereas increased legumain expression increased the levels of Beclin1 and LC3 significantly. CONCLUSION Legumain regulates oxLDL-induced macrophage apoptosis by enhancing the autophagy pathway, which may also influence the vulnerability of atherosclerotic plaques.

Kir4.1 channels in NG2-glia play a role in development, potassium signaling, and ischemia-related myelin loss

The contribution of the inwardly rectifying K+ channel subtype Kir4.1 has been focused mainly on astrocytes, where they play important roles in the maintenance of resting membrane potential, extracellular K+ uptake, and facilitation of glutamate uptake in the central nervous system. Here, we report the role of Kir4.1 channels in NG2-glia during brain development, potassium signaling, and in an ischemic stroke disease model. Kir4.1 channels are widely expressed in NG2-glia during brain development. In the adult mouse hippocampus, Kir4.1 channels in NG2-glia constitute more than 80% of K+ channels inward currents. This large portion of Kir4.1 channel currents exhibits a deficit in NG2-glia as an initial response in a transient ischemic mouse model. Further evidence indicates that Kir4.1 deficits in NG2-glia potentially cause axonal myelin loss in ischemia through the association with oligodendrocyte-specific protein (OSP/Claudin-11), which unravels a potential therapeutic target in the treatment of ischemic stroke.Feier Song and colleagues have examined Kir4.1 channels in the mouse brain, and found global expression of functional channels during development. They also show that depletion of Kir4.1 channels impacts demyelination in ischemic stroke