Genetically identified mediators associated with increased risk of stroke and cardiovascular disease in individuals with autism spectrum disorder.

Growing evidence suggested that individuals with autism spectrum disorder (ASD) associated with stroke and cardiovascular disease (CVD). However, the causal association between ASD and the risk of stroke and CVD remains unclear. To validate this, we performed two-sample Mendelian randomization (MR) and two-step mediation MR analyses, using relevant genetic variants sourced from the largest genome-wide association studies (GWASs). Two-sample MR evidence indicated causal relationships between ASD and any stroke (OR = 1.1184, 95% CI: 1.0302-1.2142, P < 0.01), ischemic stroke (IS) (OR = 1.1157, 95% CI: 1.0237-1.2160, P = 0.01), large-artery atherosclerotic stroke (LAS) (OR = 1.2902, 95% CI: 1.0395-1.6013, P = 0.02), atrial fibrillation (AF) (OR = 1.0820, 95% CI: 1.0019-1.1684, P = 0.04), and heart failure (HF) (OR = 1.1018, 95% CI: 1.0007-1.2132, P = 0.05). Additionally, two-step mediation MR suggested that type 2 diabetes mellitus (T2DM) partially mediated this effect (OR = 1.14, 95%CI: 1.02-1.28, P = 0.03). The mediated proportion were 10.96% (95% CI: 0.58%-12.10%) for any stroke, 11.77% (95% CI: 10.58%-12.97%) for IS, 10.62% (95% CI: 8.04%-13.20%) for LAS, and 7.57% (95% CI: 6.79%-8.36%) for HF. However, no mediated effect was observed between ASD and AF risk. These findings have implications for the development of prevention strategies and interventions for stroke and CVD in patients with ASD.

Particulate matter 2.5 causally increased genetic risk of autism spectrum disorder.

BACKGROUND: Growing evidence suggested that particulate matter (PM) exhibit an increased risk of autism spectrum disorder (ASD). However, the causal association between PM and ASD risk remains unclear. METHODS: We performed two-sample Mendelian randomization (MR) analyses, using instrumental variables (IVs) sourced from the largest genome-wide association studies (GWAS) databases. We employed three MR methods: inverse-variance weighted (IVW), weighted median (WM), and MR-Egger, with IVW method serving as our primary MR method. Sensitivity analyses were performed to ensure the stability of these findings. RESULTS: The MR results suggested that PM2.5 increased the genetic risk of ASD (ß = 2.41, OR = 11.13, 95% CI: 2.54-48.76, P < 0.01), and similar result was found for PM2.5 absorbance (ß = 1.54, OR = 4.67, 95% CI: 1.21-18.01, P = 0.03). However, no such association was found in PM10 (ß = 0.27, OR = 1.30, 95% CI: 0.72-2.36, P = 0.38). After adjusting for the false discovery rate (FDR) correction, our MR results remain consistent. Sensitivity analyses did not find significant heterogeneity or horizontal pleiotropy. CONCLUSIONS: Our findings indicate that PM2.5 is a potential risk factor for ASD. Effective strategies to mitigate air pollutants might lead to a reduced incidence of ASD.

Inferring the genetic effects of serum homocysteine and vitamin B levels on autism spectral disorder through Mendelian randomization.

PURPOSE: The previous studies have suggested that serum homocysteine (Hcy) and vitamin B levels are potentially related to autism spectrum disorder (ASD). However, the causality between their concentrations and ASD risk remains unclear. To elucidate this genetic association, we used a Mendelian randomization (MR) design. METHODS: For this MR analysis, 47 single-nucleotide polymorphisms (SNPs)-13 related to Hcy, 13 to folate, 14 to vitamin B6, and 7 to vitamin B12-were obtained from a large-scale Genome-Wide Association Studies (GWAS) database and employed as instrumental variables (IVs). Our study used three approaches to calculate the MR estimates, including inverse-variance weighted (IVW) method, MR-Egger method, and weighted median (WM) method. Among these, the IVW method served as our primary MR method. False discovery rate (FDR) was implemented to correct for multiple comparisons. We also performed a series of sensitivity analyses, including Cochran's Q test, MR-Egger's intercept, MR-PRESSO, leave-one-out analysis, and the funnel plot. RESULTS: Univariable Mendelian randomization (UVMR) analysis revealed a statistical association between serum vitamin B12 levels and ASD risk (OR = 1.68, 95% CI 1.12-2.52, P = 0.01) using the IVW method. However, neither the WM method (OR = 1.57, 95% CI 0.93-2.66, P = 0.09) nor the MR-Egger method (OR = 2.33, 95% CI 0.48-11.19, P = 0.34) was significantly association with higher levels of serum vitamin B12 and ASD risk. Additionally, we found no evidence of causal relationships between serum levels of vitamin B6, folate, Hcy, and ASD risk. After correcting for the FDR, the causality between serum vitamin B12 levels and ASD risk remained significant (q value = 0.0270). Multivariate Mendelian randomization (MVMR) analysis indicated an independent association between elevated serum vitamin B12 levels and the risk of ASD (OR = 1.74, 95% CI 1.03-2.95, P = 0.03) using the IVW method, but this finding was inconsistent when using the WM method (OR = 1.73, 95% CI 0.89-3.36, P = 0.11) and MR-Egger method (OR = 1.60, 95% CI 0.95-2.71, P = 0.08). Furthermore, no causal associations were observed for serum levels of vitamin B6 and folate in MVMR analysis. Sensitivity analyses confirmed that these results were reliable. CONCLUSION: Our study indicated that elevated serum vitamin B12 levels might increase the risk of ASD. The potential implications of our results for ASD risk warrant validation in randomized clinical trials.

TRPV1 Suppressed NLRP3 Through Regulating Autophagy in Microglia After Ischemia-Reperfusion Injury.

The microglia-mediated inflammatory response is one of the main causes of brain tissue damage after stroke. In recent years, it has been reported that autophagy in microglia played an important role in inflammatory response after stroke. Transient receptor potential vanilloid 1 (TRPV1) has been shown to regulate autophagy and inflammatory in microglia; however, the detailed mechanisms remain unclear. This study aimed to investigate whether autophagy regulates inflammatory is associated with TRPV1. Model of oxygen and glucose deprivation/reoxygenation (OGD/R) was established in vitro to induce cerebral ischemia-reperfusion injury (I/R). siRNA of Atg5, inhibitors, and agonists of both autophagy and TRPV1 were involved in our study. Autophagy was assayed by immunofluorescence staining LC-3 and autophagosome was observed using transmission electron microscopy (TEM). Autophagy/inflammation-related markers as Atg5, LC-3II/LC-3I, Beclin-1, NLRP3, IL-1ß, and Caspase-1 were also measured in the present study. Results indicated that I/R injury-induced inflammatory injury may be impeded by inhibition of autophagy, and TRPV1 could suppress OGD/R-induced autophagy of microglia. However, the effect of TRPV1's inhibitor on inflammatory response was attenuated when the autophagy was blocked. These findings suggested that TRPV1 exhibits an anti-inflammatory effect on OGD/R-induced microglia, which was at least correlated with the anti-autophagy action of TRPV1 partially.

The Synergistic Effect of TRPV1 on Oxidative Stress-Induced Autophagy and Apoptosis in Microglia.

Stroke mostly including ischemic stroke is the second leading mortality and disability worldwide. Oxidative stress injury occurred during ischemic stroke treatment generally. A high amount of reactive oxygen species (ROS) is involved in oxidative stress induction. Transient receptor potential vanilloid 1 (TRPV1) has been shown to regulate oxidative stress and apoptosis in microglia; however, the detailed mechanisms remain unclear. We aimed to explore whether autophagy-regulated oxidative stress and apoptosis are associated with TRPV1. The model of oxygen and glucose deprivation (OGD/R) in microglia was established. The siRNA of Atg5 and inhibitors and agonists of both autophagy and TRPV1 were involved in our study. Autophagy-related markers Atg5, LC3II/LC3I, and Beclin-1 were measured, and the autophagosome was observed under a transmission electron microscope (TEM). Caspase 3 was detected using ELISA. ROS and JC-1 were detected using flow cytometry. Apoptosis was observed by TUNEL. The results indicated that oxidative stress-induced injury and apoptosis may be impeded by the increasing autophagy, and TRPV1 inhibition could suppress the OGD/R-induced autophagy of microglia. However, the effect of TRPV1's inhibitor on oxidative stress and apoptosis was not obvious when the autophagy was blocked. These findings suggested that TRPV1 may exhibit antioxidative and antiapoptosis effect on OGD/R-induced microglia. However, the experimental results do not fully demonstrate that the TRPV1-mediated antioxidative and antiapoptosis effect is through the affecting autophagy entirely.

Effects of Treadmill Exercise on Motor and Cognitive Function Recovery of MCAO Mice Through the Caveolin-1/VEGF Signaling Pathway in Ischemic Penumbra.

Exercise has been regarded as an effective rehabilitation strategy to facilitate motor and cognitive functional recovery after stroke, even though the complex effects associated with exercise-induced repair of cerebral ischemic injury are not fully elucidated. The enhancement of angiogenesis and neurogenesis, and the improvement of synaptic plasticity following moderate exercise are conducive to functional recovery after ischemic damage. Our previous studies have confirmed the angiogenesis and neurogenesis through the caveolin-1/VEGF pathway in MCAO rats. As an essential neurotrophic factor, BDNF has multiple effects on ischemic injury. In this study, we attempted to determine an additional mechanism of treadmill exercise-mediated motor and cognitive functional recovery through the caveolin-1/VEGF pathway associated with BDNF in the ischemic penumbra of MCAO mice. We found that mice exposed to treadmill exercise after the MCAO operation showed a significant up-regulation in expression of caveolin-1, VEGF, BDNF, synapsin I and CYFIP1 proteins, numbers of cells positive for BrdU/CD34, BDNF, BrdU/NeuN, BrdU/Synapsin I and CYFIP1 expression were increased, which support the reduction in neurological deficit and infarction volume, as well as improved synaptic morphology and spatial learning abilities, compared with the non-exercise mice. However, the caveolin-1 inhibitor, daidzein, resulted in increase in neurological deficit and infarction volume. The selective VEGFR2 inhibitor, PD173074, significantly induced larger infarction volume and neurological injury, and decreased the expression of BDNF in the ischemic penumbra. These findings indicate that exercise improves angiogenesis, neurogenesis and synaptic plasticity to ameliorate motor and cognitive impairment after stroke partially through the caveolin-1/VEGF pathway, which is associated with the coregulator factor, BDNF.

Treadmill exercise ameliorates focal cerebral ischemia/reperfusion-induced neurological deficit by promoting dendritic modification and synaptic plasticity via upregulating caveolin-1/VEGF signaling pathways.

Dendritic and synaptic plasticity in the penumbra are important processes and are considered to be therapeutic targets of ischemic stroke. Treadmill exercise is known to be a beneficial treatment following stroke. However, its effects and potential mechanism in promoting dendritic and synaptic plasticity remain unknown. We have previously demonstrated that the caveolin-1/VEGF signaling pathway plays a positive role in angiogenesis and neurogenesis. Here, we further investigated the effects of treadmill exercise on promoting dendritic and synaptic plasticity in the penumbra and whether they involve the caveolin-1/VEGF signaling pathway. A middle cerebral artery occlusion (MCAO) animal model was established, and rats were randomly divided into eleven groups. At 2 days after MCAO, rats were subjected to treadmill exercise for 7 or 28 days. Daidzein (a specific inhibitor of caveolin-1, 0.4 mg/kg) was used to confirm the effect of caveolin-1/VEGF signaling on exercise-mediated dendritic and synaptic plasticity. Neurobehavioral performance, tissue morphology and infarct volumes were detected by Modified Neurology Severity Score (mNSS), Hematoxylin-eosin (HE), and Nissl staining, while neural plasticity and its molecular mechanism were examined by Golgi-Cox staining, transmission electron microscopy, western blot analysis and immunofluorescence. We found that treadmill exercise promoted dendritic plasticity in the penumbra, consistent with the significant increase in caveolin-1 and VEGF expression; improved neurological recovery; and reduced infarct volume. In contrast to the positive effects of the treadmill, a caveolin-1 inhibitor abrogated the dendritic and synaptic plasticity. Furthermore, we observed that treadmill exercise-induced improved dendritic and synaptic plasticity were significantly inhibited by the caveolin-1 inhibitor, consistent with the lower expression of caveolin-1 and VEGF, as well as the worse neurobehavioral state. The findings indicate that treadmill exercise ameliorates focal cerebral ischemia/reperfusion-induced neurological deficit by promoting dendritic and synaptic plasticity via upregulating caveolin-1/VEGF signaling pathways.

Apigenin Protects the Brain against Ischemia/Reperfusion Injury via Caveolin-1/VEGF In Vitro and In Vivo.

Apigenin is a natural flavonoid found in several dietary plant foods as vegetables and fruits. To investigate potential anti-ischemia/reperfusion injury properties of apigenin in vitro, cell proliferation assay, tube formation, cell migration, apoptosis, and autophagy were performed in human brain microvascular endothelial cells (HBMVECs) after oxygen-glucose deprivation/reoxygenation (OGD/R). The effect of apigenin was also explored in rats after middle cerebral artery occlusion/reperfusion (MCAO/R) via neurobehavioral scores, pathological examination, and measurement of markers involved in ischemia/reperfusion injury. Data in vitro indicated that apigenin could prompt cell proliferation, tube formation, and cell migration while inhibiting apoptosis and autophagy by affecting Caveolin-1/VEGF, Bcl-2, Caspase-3, Beclin-1, and mTOR expression. Results in vivo showed that apigenin significantly reduced neurobehavioral scores and volume of cerebral infarction while prompting vascular endothelial cell proliferation by upregulating VEGFR2/CD34 double-labeling endothelial progenitor cell (EPC) number and affecting Caveolin-1, VEGF, and eNOS expression in brain tissue of MCAO/R rats. All the data suggested that apigenin may be protective for the brain against ischemia/reperfusion injury by alleviating apoptosis and autophagy, promoting cell proliferation in HBMVECs of OGD/R, and attenuating brain damage and improved neurological function in rats of MCAO/R through the Caveolin-1/VEGF pathway.

Angiogenic effects of apigenin on endothelial cells after hypoxia-reoxygenation via the caveolin-1 pathway.

In the present study, we aimed to elucidate whether apigenin contributes to the induction of angiogenesis and the related mechanisms in cell hypoxia-reoxygenation injury. The role of apigenin was examined in human umbilical vein endothelial cell (HUVEC) viability, migration and tube formation in vitro. To investigate the related mechanisms, we used caveolin-1 short interfering RNA. The viability of HUVECs was measured using Cell Counting Kit-8 assays, HUVEC migration was analyzed by crystal violet staining, and a tube formation assay was performed using the branch point method. Expression of caveolin-1, vascular endothelial growth factor (VEGF), and endothelial nitric oxide synthase (eNOS) in HUVECs was examined by polymerase chain reaction and western blotting. Our data revealed that apigenin induced angiogenesis in vitro by increasing the tube formation ability of HUVECs, which was counteracted by caveolin-1 silencing. Compared to the NC group, Caveolin-1 and eNOS expression was upregulated by apigenin, whereas compared to the NC group, eNOS expression was increased upon caveolin-1 silencing. The expression of VEGF was increased by treatment with apigenin; however, compared to the NC group, caveolin-1 silencing did not affect VEGF expression, and apigenin did not increase VEGF expression in HUVECs after caveolin-1 silencing. These data suggest that apigenin may be a candidate therapeutic target for stroke recovery by promoting angiogenesis via the caveolin-1 signaling pathway.

Apigenin Ameliorates Post-Stroke Cognitive Deficits in Rats Through Histone Acetylation-Mediated Neurochemical Alterations.

BACKGROUND To identify the effect of apigenin on cognitive deficits of rats after cerebral ischemia and reperfusion injury, and to investigate the potential molecular mechanisms. MATERIAL AND METHODS The rats were given sodium butyrate (NaB) or apigenin (20 or 40 mg/kg) for 28 days. Cognition was investigated by the Morris water maze (MWM) test. On day 28, the rats were euthanized and their hippocampal brain regions were used to identify biochemical and neurochemical alterations. The content of histone deacetylase (HDAC) was measured by enzyme-linked immunosorbent assay (ELISA). Western blot analysis was performed to determine the levels of BDNF, phosphorylated cAMP response element-binding protein (pCREB), acetylated H3, and acetylated H4. The mRNA expressions of brain-derived neurotrophic factor (BDNF) and synapsin-I (Syn-I) were examined by polymerase chain reaction (PCR). RESULTS The rats with chronic administration of apigenin (20 and 40 mg/kg) showed better performance in the MWM task than the model rats; there was no significant difference between the apigenin-treated and NaB-treated rats. At the higher apigenin dose of 40 mg/kg, the HDAC content was decreased, the BDNF level was markedly increased, and acetylated H3 and acetylated H4 expressions and Syn-I expressions in the hippocampus was upregulated compared with the model group. Apigenin at 20 mg/kg did not show reversal of the neurochemical alterations. CONCLUSIONS The improvement effect of apigenin on cognitive impairments after cerebral ischemia and reperfusion injury may involve multiple mechanisms, such as the inhibition of HDAC, induction of BDNF and Syn-I expression, and regulation of histone acetylation.

Role of caveolin-1/vascular endothelial growth factor pathway in basic fibroblast growth factor-induced angiogenesis and neurogenesis after treadmill training following focal cerebral ischemia in rats.

Exercise is known to aid functional recovery following ischemia, though the mechanisms responsible for the beneficial effects of exercise on recovery from ischemic stroke are not fully understood. Basic fibroblast growth factor (bFGF) contributes to angiogenesis and promotes neurologic functional recovery after stroke. The present study aimed to investigate the possible mechanisms whereby treadmill exercise ameliorated impaired angiogenesis and neurogenesis following transient cerebral ischemia in middle cerebral artery occlusion (MCAO) rats. Treadmill exercise was started 2days after ischemia-reperfusion in MCAO rats and continued until 7 or 28days after MCAO, after which the animals were sacrificed. Changes in neurological deficit, infarction volume, neuronal morphology, expression levels of bFGF, caveolin-1, and vascular endothelial growth factor (VEGF), and angiogenesis and neurogenesis in the ischemic penumbra were examined by reverse transcription-polymerase chain reaction, western blots, and/or double immunofluorescence. The results suggested that treadmill exercise promoted the expression of bFGF, improved neurological recovery, and reduced infarct volume compared with non-exercised rats, and also enhanced the expression of caveolin-1, VEGF, VEGF receptor 2(FIK-1)/CD34, and Brdu/nestin staining. Small interfering RNA targeting bFGF blocked the protective effects of bFGF. In addition, 4weeks of post-stroke recovery still ameliorated ischemia-induced damage without bFGF shRNA. These findings suggest a novel mechanism underlying the beneficial effects of bFGF following stroke, and indicate that treadmill exercise may aid stroke recovery by regulating the caveolin-1/VEGF pathway in the ischemic zone.

Treadmill Exercise Promotes Neurogenesis in Ischemic Rat Brains via Caveolin-1/VEGF Signaling Pathways.

Using a model of middle cerebral artery occlusion (MCAO), we have previously demonstrated that treadmill exercise promotes angiogenesis in the ischemic penumbra through caveolin-1/VEGF signaling pathways. However, the function of caveolin-1/VEGF signaling in neurogenesis after MCAO has not been determined. In this study, we aimed to investigate the potential of treadmill exercise to promote neurogenesis after MCAO and whether caveolin-1/VEGF signaling pathways are involved. After MCAO, rats were subjected to a program of treadmill exercise. Daidzein (a specific inhibitor of caveolin-1 protein expression, 0.4 mg/kg) was used to confirm the effect of caveolin-1/VEGF signaling on exercise-mediated neurogenesis. We found that the total protein expression of both caveolin-1 and VEGF was increased by exercise and consistent with the improved neurological recovery, decreased infarct volumes and increased 5-bromo-2'-deoxyuridine (BrdU) in the ipsilateral Subventricular zone (SVZ), as well as increased numbers of BrdU/DCX and BrdU/Neun-positive cells in the peri-infarct region. Furthermore, we observed that the treadmill exercise-induced increased VEGF expression, improved neurological recovery, decreased infarct volumes, increased BrdU/DCX and BrdU/Neun-positive cells were significantly inhibited by the caveolin-1 inhibitor. Our results indicate that treadmill exercise improves neurological recovery in ischemic rats, possibly by enhancement of SVZ-derived neural stem cell (NSC) proliferation, migration and differentiation in the penumbra. Moreover, caveolin-1/VEGF signaling is involved in exercise-mediated NSC migration and neuronal differentiation.

Effect of integrated traditional Chinese and Western medicine therapy for acute hypertensive intracerebral hemorrhage: a meta-analysis.

Intracerebral hemorrhage (ICH) is an important public health problem associated with high mortality and morbidity. The aim of this study was to evaluate the clinical efficacy of integrated traditional Chinese (TCM) and Western medicine (WM) therapy for acute hypertensive ICH. Randomized controlled trials were searched in PubMed, Medline, Embase, Wanfang and CNKI database published between January 2000 and June 2016. Our results showed that integrated TCM and WM therapy appeared to be able to improve the clinical effect for patients with acute hypertensive ICH.