The prognostic value of caveolin-1 levels in ischemic stroke patients after mechanical thrombectomy.

BACKGROUND AND PURPOSE: The impact of serum caveolin-1 (Cav-1) on clinical outcomes in patients after mechanical thrombectomy (MT) is unclear. We aimed to investigate the association between serum cav-1 levels and the 3-month functional outcome. METHODS: We prospectively enrolled and analyzed patients with an anterior circulation large vessel occlusion who underwent MT. Serum cav-1 concentrations were tested after admission. The primary outcome was a 90-day modified Rankin Scale score of 3-6. RESULTS: Of the 237 recruited patients (mean age, 69.7 ± 12.1 years; 152 male), 131 (55.3%) experienced a 90-day poor outcome. After adjustment for demographic characteristics and other covariates, patients with higher serum Cav-1 levels had a reduced risk of poor outcome at 3 months (Per 1-standard deviation increase; odd ratios [OR], 0.59; 95% confidence interval [CI], 0.39 - 0.89, P = 0.013). Elevated Cav-1 concentrations (Per 1-standard deviation increase; OR, 0.59; 95% CI, 0.40 - 0.88, P = 0.011) were significantly associated with a favorable shift in modified Rankin Scale score distribution. Similar results were confirmed when the Cav-1 levels were analyzed as a categorical variable. Furthermore, the restricted cubic spline showed a linear association between Cav-1 levels and 90-day poor outcome (P = 0.032 for linearity). CONCLUSIONS: Increased serum Cav-1 levels were associated with improved prognosis at 3 months in ischemic stroke patients after MT, suggesting that Cav-1 may be a potential prognostic biomarker for ischemic stroke after reperfusion therapy.

Hypersensitive C-reactive protein-albumin ratio predicts symptomatic intracranial hemorrhage after endovascular therapy in acute ischemic stroke patients.

BACKGROUND: Approximately 10% of patients would develop symptomatic intracranial hemorrhage (sICH) after endovascular therapy. The aim of our study was to explore the ability of hypersensitive C-reactive protein-albumin ratio (HAR) in predicting sICH after endovascular therapy. METHODS: From April 2016 to December 2018, 334 consecutive patients with anterior circulation infarction undergoing endovascular therapy were enrolled in our study. sICH was defined using Heidelberg bleeding classification after endovascular therapy. Multiple regression analysis was used to investigate the potential risk factors of sICH after endovascular therapy. We used receiver operating characteristic curve analysis and nomogram analysis to assess the overall discriminative ability of the HAR in predicting sICH after endovascular therapy. RESULTS: Among these 334 patients enrolled, 37 (11.1%) patients with anterior circulation infarction were identified with sICH after endovascular therapy. Univariate logistic regression analysis demonstrated that patients with higher levels of HAR may be inclined to develop sICH (odds ratio, 10.994; 95% confidence interval, 4.567-26.463; P = 0.001). This association remained significant even after adjustment for potential confounders. Also, a cutoff value of 0.526× 10- 3 for HAR was detected in predicting sICH (area under curve, 0.763). Furthermore, nomogram analysis also suggested that HAR was an indicator of sICH (c-index was 0.890, P< 0.001). CONCLUSIONS: This study showed that high levels of HAR could predict sICH after endovascular therapy.

LPA kringle IV type 2 is associated with type 2 diabetes in a Chinese population with very high cardiovascular risk.

The connection between lipoprotein (a) [Lp(a)] levels and the risks of cardiovascular disease and diabetes remains poorly understood. Lp(a) is encoded by the LPA gene, and evidence suggests that the kringle IV type 2 (KIV-2) variant is particularly important to Lp(a) isoform size. A large isoform size, represented as a high number of KIV-2 repeats in LPA, is associated with low serum Lp(a) concentrations and an increased risk of type 2 diabetes. We investigated the associations among Lp(a) concentrations, LPA KIV-2 repeats, and type 2 diabetes in a Chinese population of 1,863 consecutive patients with very high cardiovascular risk, as identified by coronary angiography. Individuals with Lp(a) levels in the top tertile [67.86 (35.34-318.50) mg/dl] had a lower risk of diabetes compared with those in the bottom tertile [7.38 (0.60-12.91) mg/dl]. There was an inverse association between the number of KIV-2 repeats and serum Lp(a) concentrations. This study demonstrated that a high number of LPA KIV-2 repeats are associated with increased risk of type 2 diabetes in a Chinese population with very high cardiovascular risk, which suggests that large Lp(a) isoform size, associated with low Lp(a) concentration, has a causal effect on type 2 diabetes.

Isoleojaponin, a new Halimane diterpene isolated from Leonurus japonicus.

Leojaponin (2), a labdane diterpene, was isolated from the EtOH extract of the herb of Leonurus japonicus together with a new halimane diterpene named isoleojaponin (1). Isoleojaponin has a new diterpene skeleton with a unique cross-conjugated α,ß-unsaturated ketone system, Their structures were elucidated by physical and spectroscopic analysis, and the relative configuration of the chiral C-9 carbon was determined by a computational method, and analysis of its possible biogenesis pathways.

Relationship Between Liver Fibrosis and Increased Risk of Symptomatic Intracranial Hemorrhage in Ischemic Stroke Patients Undergoing Mechanical Thrombectomy.

Background: Liver fibrosis has been reported to be associated with hematoma expansion and mortality in patients with intracerebral hemorrhage. This study aimed to detect the association between liver fibrosis and symptomatic intracranial hemorrhage (sICH) in ischemic stroke after mechanical thrombectomy (MT). Methods: We retrospectively included patients with large artery occlusion in the anterior circulation and treated with MT at a single stroke center. The fibrosis-4 index (FIB-4) was used to assess the severity of liver fibrosis. sICH was diagnosed according to the Heidelberg Bleeding Classification criteria. Multivariate logistic regression and restricted cubic spline analysis were conducted to examine the relationship between liver fibrosis and sICH. Results: Among the 578 patients (mean age, 70.1 years; 58.5% male) included in the study, 65 (11.2%) individuals were diagnosed with sICH. After adjusting for demographic characteristics and other potential confounders, a higher FIB-4 index was found to be independently associated with an increased risk of sICH (odds ratio: 1.306, 95% confidence interval: 1.127-1.512, P=0.001). Similar results were obtained when analyzing FIB-4 as a categorical variable. Conclusion: This study demonstrated that there is a significant association between FIB-4 and the risk of sICH in patients with acute ischemic stroke who underwent MT. Therefore, liver fibrosis could serve as a valuable parameter in monitoring the risk of sICH following MT.

Association between Citrullinated Histone H3 and White Matter Lesions Burden in Patients with Ischemic Stroke.

INTRODUCTION: Neutrophil extracellular traps play a role in the pathophysiology of stroke and are associated with severity and mortality. We aimed to investigate whether the citrullinated histone H3 (CitH3), a biomarker for neutrophil extracellular traps formation, is associated with the white matter lesion (WML) burden in ischemic stroke patients. METHODS: Between September 2021 and April 2022, 322 patients were enrolled in this prospective observational cohort study. Serum CitH3 levels were measured after admission using an enzyme-linked immunosorbent assay. WMLs severity was graded according to the Fazekas scale and conceptually defined as mild (total Fazekas score 0-2) and severe (total Fazekas score 3-6). We used multivariable regression models to determine the relationship between CitH3 concentrations and the severity of WMLs burden. RESULTS: One-hundred and forty-eight (46.0%) patients were diagnosed with severe WMLs burden after admission. Increased CitH3 levels (first quartile vs. fourth quartile of H3Cit, odds ratio, 3.311, 95% confidence interval, 1.336-8.027; p = 0.011) were independently associated with a greater WML burden in the fully adjusted multivariable model. Similar results were found when the H3Cit was analyzed as a continuous variable. Furthermore, the multiple-adjusted spline regression model showed a linear association between H3Cit levels and severe WMLs (P = 0.001 for linearity). CONCLUSIONS: In the present study, increased CitH3 levels were positively associated with extensive WMLs in ischemic stroke patients, indicating a role of neutrophil extracellular traps formation in the pathogenesis of WMLs.

Higher Serum E-Selectin Levels Associated with Malignant Brain Edema after Endovascular Thrombectomy for Ischemic Stroke: A Pilot Study.

Background and Purpose: Little is known about the effect of soluble adhesion molecules on malignant brain edema (MBE) after endovascular thrombectomy (EVT). This study aimed to explore the association between serum concentrations of E-selectin and the risk of MBE in patients who received EVT. Methods: Patients with a large vessel occlusion stroke in the anterior circulation who underwent EVT were prospectively recruited. Serum soluble E-selectin concentrations were measured after admission for all patients. MBE was defined as a midline shift of ≥5 mm on follow-up imaging within 72 h after surgery. Multivariate logistic regression analyses were performed to determine the association between E-selectin levels and the risk of MBE. Results: Among the 261 included patients (mean age, 69.7 ± 12.3 years; 166 males), 59 (22.6%) developed MBE. Increasing circulating E-selectin levels were associated with an increased risk of MBE after multivariable adjustment (odds ratios [OR], highest vs. lowest quartile: 3.593; 95% confidence interval [CI], 1.178-10.956; p = 0.025). We further observed a significantly positive association between E-selectin and MBE (per 1-standard deviation increase; OR, 1.988; 95% CI, 1.379-2.866, p = 0.001) when the E-selectin levels were analyzed as a continuous variable. Furthermore, the restricted cubic spline demonstrated a linear correlation between serum E-selectin levels and the risk of MBE (p < 0.001 for linearity). Conclusions: In this prospective study, circulating levels of E-selectin were associated with an increased risk of MBE after EVT. Further mechanistic studies are warranted to elucidate the pathophysiology underlying this association.

A Novel Metabolic Score for Insulin Resistance and Symptomatic Intracranial Hemorrhage in Ischemic Stroke Patients After Endovascular Thrombectomy.

Background and Purpose: Insulin resistance plays a pivotal role in the pathophysiology of ischemic stroke. This study aimed to determine the relationship between the novel metabolic score for insulin resistance (METS-IR) and symptomatic intracranial hemorrhage (sICH) after endovascular thrombectomy (EVT) in stroke patients. Methods: We retrospectively included patients with large artery occlusion in the anterior circulation and treated by EVT from 2 stroke centers (Nanjing First Hospital from September 2019 to April 2022, and Jinling Hospital from September 2019 to July 2021). The METS-IR was used as an alternative marker of insulin resistance and calculated using laboratory data after admission. sICH was diagnosed according to the Heidelberg Bleeding Classification. Results: Of the 410 enrolled patients (mean age, 69.8 ± 11.7 years; 60.7% men), 50 (12.2%) were diagnosed as sICH. After adjusting for demographic characteristics, poor collateral status, and other potential confounders, higher METS-IR was revealed to be independently associated with sICH (odds ratio, 1.076; 95% confidence interval, 1.034-1.120; P = 0.001). Similar significant results were obtained when defining METS-IR as a categorical variable. The restricted cubic spline uncovered a linear relationship between METS-IR and sICH (P < 0.001 for linearity). Furthermore, adding METS-IR to the conventional model significantly improved the risk prediction for sICH (net reclassification improvement = 15.8%, P = 0.035; integrated discrimination index = 2.6%; P = 0.017). Conclusion: This study demonstrated a significant association between METS-IR score and sICH in ischemic stroke patients treated with EVT. It could help monitor and manage sICH in patients after EVT.

The Relationship Between Neuron-Specific Enolase and Clinical Outcomes in Patients Undergoing Mechanical Thrombectomy.

Purpose: Neuron-specific enolase (NSE) is considered a biomarker for the severity of nervous system diseases. We sought to explore whether serum NSE concentration in ischemic stroke patients undergoing mechanical thrombectomy (MT) is related to 3-month functional outcome and symptomatic intracranial hemorrhage (sICH). Patients and Methods: We retrospectively collected the data of acute ischemic stroke patients with anterior circulation infarction receiving MT within 6 h in our stroke center. Favorable outcome and poor outcome at 3 months were defined as modified Rankin Scale (mRS) score 0-2 and 3-6, respectively. sICH was defined according to the Heidelberg bleeding classification. We used multivariate logistic regression model and receiver operating characteristic curves to investigate the correlation between NSE and clinical outcomes. Results: Among the 426 patients enrolled, 40 (9.4%) patients developed sICH. Three-month favorable outcome in 160 (37.6%) and poor outcome in 266 (62.4%) patients were observed. Serum NSE levels was significantly correlated with 3-month mRS score (R = 0.473, P < 0.001). A cutoff value of 15.29 and 23.12 ng/mL for serum NSE was detected in discriminating 3-month poor outcome (area under the curve, 0.724) and sICH (area under the curve, 0.716), respectively. Multivariate analysis showed that high serum NSE levels were independently associated with 3-month poor outcome (odds ratio [OR] 5.049, 95% confidence interval [CI] 2.933-8.689, P<0.001) and sICH (OR 5.111, 95% CI 2.210-11.820, P < 0.001). Conclusion: Our study demonstrated that high serum NSE levels after receiving MT were independently associated with 3-month poor outcome and sICH in acute ischemic stroke patients. Serum NSE levels could be a good predictor of clinical outcomes for patients receiving MT.

Prognostic performance of serum YKL-40 for one-year clinical outcomes in acute ischemic stroke.

BACKGROUND: Effects of YKL-40 on one-year clinical outcomes including poor clinical outcome, all-cause mortality, and stroke recurrence among acute ischemic stroke (AIS) patients remained elusive. The purpose of this study was to explore the association between serum YKL-40 at admission and one-year clinical outcomes in AIS patients. METHODS: In this prospective cohort study, a total of 1002 participants out of 1361 AIS patients from two centers were included for current analysis. Serum YKL-40 concentrations were measured via enzyme-linked immunosorbent assay. Multivariable logistic or Cox regression were performed to explore the independent association of YKL-40 with one-year clinical outcomes, including poor outcome (modified Rankin Scale of 3-6), all-cause mortality, and recurrent stroke. C-statistic, net reclassification index (NRI) and integrated discrimination improvement (IDI) were calculated to evaluate the discriminatory and predictive power of YKL-40 when added to conventional model. RESULTS: Compared with the first quartile of YKL-40, the adjusted odds ratios or hazard ratios with 95% confidence intervals of the fourth quartile were 3.032 (1.627-5.650) for poor outcome, 2.886 (1.320-6.308) for all-cause mortality and 1.694 (0.906-3.169) for recurrent stroke. The addition of serum YKL-40 to conventional model significantly improved reclassification for poor outcome (NRI 0.053, P = 0.031; IDI 0.018, P = 0.001) and all-cause mortality (NRI 0.162, P = 0.036). CONCLUSIONS: Elevated serum YKL-40 at admission might be independently associated with one-year poor outcome and all-cause mortality but not stroke recurrence among Chinese AIS patients.

Valproate-induced hyperammonemic encephalopathy treated by L-ornithine-L-aspartate: a case report.

A 63-year-old man developed reduced consciousness and dysphagia progressively. Examination and parameters were normal, except for a Glasgow Coma Scale score of seven, and his grading on the swallow water test increased from grade 1 to grade 5. Brain imaging and blood tests were unexplainable except by high plasma ammonia. His past medical history included cerebral infarction, hypertension and epilepsy induced by cerebral hyperperfusion syndrome. He was rceiving antiepileptic treatment of continuously intravenously pumped sodium valproate of 64 mg/h for 4 days, which overlapped for 12 hours with taking 500 mg sustained release tablets. Sodium valproate was stopped; testing demonstrated normal plasma concentrations of sodium valproate and elevated concentrations of ammonia. Ornithine aspartate was administrated. The patient's level of responsiveness and ammonia levels gradually improved. The patient was also being treated with ceftriaxone sodium for a hypostatic pneumonia and with desmopressin for diabetes insipidus. There is an association between sodium valproate and hyperammonaemia and encephalopathy. Immediate recognition of the serious but uncommon adverse effects is essential. To our knowledge this is the first report of ornithine aspartate being used in this disorder.

Developments in high-throughput functional epigenomics: CRISPR-single-cell assay for transposase-accessible chromatin using sequencing screens.

Tweetable abstract CRISPR-scATAC-seq screens pave the way for high-throughput functional epigenomics by linking perturbations to a broad view of epigenetic state and messages hidden within accessible sequences.

Levels of adhesion molecules and clinical outcomes in patients with ischemic stroke after mechanical thrombectomy.

Background and purpose: Data on adhesion molecule levels in patients treated with mechanical thrombectomy (MT) are scarce. We aimed to evaluate the association among adhesion molecule levels, symptomatic intracranial hemorrhage (sICH), and clinical outcome and to determine whether the sICH influences the association of adhesion molecules with functional outcome. Methods: Patients with large artery occlusion in the anterior circulation and treated with MT were prospectively recruited. Adhesion molecules, such as soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1 (sVCAM-1), and soluble E-selectin (sE-selectin) were tested. An unfavorable outcome was defined as a 90-day modified Rankin Scale (mRS) score of 3-6. The sICH was diagnosed according to the Heidelberg Bleeding Classification within 72 h of endovascular treatment (EVT). Results: Of the 310 enrolled patients (mean age, 68.5 years; 198 men), 46 (14.8%) experienced sICH and 173 (55.8%) experienced an unfavorable outcome at 90 days. After adjusting for potential confounders, patients with higher sVCAM-1 and sE-selectin levels had an increasing trend of sICH [4th quartile vs. 1st quartile for sVCAM-1; odds ratio (OR), 2.766, p = 0.085; sE-selectin; OR, 2.422, p = 0.086] and poor outcome (4th quartile vs. 1st quartile for sVCAM-1; OR, 2.614, p = 0.025; sE-selectin; OR, 2.325, p = 0.046). Furthermore, the sICH might partially mediate the worse functional outcome in patients with higher adhesion molecules levels (Sobel test, p < 0.001 for sVCAM-1 and p = 0.007 for sE-selectin). Conclusions: There were significant relationships between levels of adhesion molecules and a 90-day poor outcome in patients with ischemic stroke treated with MT, which was partially mediated by sICH.

Clopidogrel with Aspirin versus Aspirin Alone following Intravenous Thrombolysis in Minor Stroke: A 1-Year Follow-Up Study.

OBJECTIVE: The objective of this study was to investigate the long-term effect of dual antiplatelet therapy (DAPT) using clopidogrel plus aspirin versus aspirin monotherapy after intravenous thrombolysis on functional outcomes in patients with minor stroke. METHODS: Patients with acute ischemic stroke with a National Institutes of Health Stroke Scale score ≤ 5 who received either DAPT or aspirin monotherapy following recombinant tissue plasminogen activator intravenous thrombolysis were studied. Data recorded between January 2017 and December 2020 were retrospectively analyzed. The primary efficacy outcome was functional improvement at 1 year, measured by a 1-point decrease across modified Rankin Scale (mRS) scores. Secondary outcomes included complete rehabilitation (mRS = 0), an excellent outcome (mRS = 0-1), and a favorable outcome (mRS = 0-2) at 1 year, as well as the rates of stroke recurrence and all-cause mortality within 1 year. RESULTS: A total of 238 patients were included, and follow-up data were available for 205 patients (86.1%). The distribution of 1-year outcomes on the mRS favored DAPT over aspirin monotherapy (adjusted common odds ratio (OR), 2.19; 95% confidence interval (CI), 1.12-4.28; p = 0.022). Patients who received DAPT, compared with those receiving aspirin alone, were more likely to achieve complete rehabilitation (adjusted OR, 2.44; 95% CI, 1.21-4.95; p = 0.013) at the 1-year follow-up. Additionally, the percentages of an excellent outcome and a favorable outcome did not differ, and the rates of stroke recurrence and all-cause mortality were comparable during the 1-year follow-up. CONCLUSIONS: Clopidogrel with aspirin following intravenous thrombolysis was associated with improved functional outcome at the 1-year follow-up for patients with minor stroke, and it did not increase the stroke recurrence rate and mortality.

Bilirubin Improves Gap Junction to Alleviate Doxorubicin-Induced Cardiotoxicity by Regulating AMPK-Axl-SOCS3-Cx43 Axis.

Doxorubicin induces severe cardiotoxicity, accompanied by the high level of bilirubin in the blood. The conventional wisdom is that bilirubin is considered as a marker of liver damage. By contrast, here we aim to explore the potential protective effect of bilirubin on doxorubicin-induced cardiotoxicity, and investigate the mechanism for drug development. Doxorubicin was used to establish cardiotoxicity model in vitro and in vivo. The electrocardiogram (ECG), echocardiography and molecular biological methods were used to detect the effects of bilirubin on doxorubicin-induced cardiotoxicity. Consecutive intraperitoneal injection of bilirubin for 7 days significantly attenuated doxorubicin-induced arrhythmia, prolonged survival time and reduced the levels of aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine kinase MB (CK-MB) and α-hydroxybutyrate dehydrogenase (α-HBDH) in mice. Bilirubin also markedly inhibited doxorubicin-induced phosphorylation of c-Jun N-terminal kinase (JNK) and connexin 43 (Cx43), and improved gap junction function in vitro and in vivo. In addition, bilirubin activated adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and induced suppressor of cytokine signaling 3 (SOCS3) expression, which was abolished by Axl inhibition. Moreover, pretreatment with AMPK agonist or AMPK inhibitor could mimic or abolish the cardioprotective effect of bilirubin on H9C2 cells in vitro, respectively. Altogether, bilirubin upregulates gap junctions' function to protect against doxorubicin-induced cardiotoxicity by activating AMPK-Axl-SOCS3 signaling axis. We enrich the physiological function of bilirubin, and provide theoretical support for drug development.

The Association between High Mobility Group Box 1 and Stroke-Associated Pneumonia in Acute Ischemic Stroke Patients.

Objective: This study aimed to investigate the association between high-mobility-group box 1 (HMGB1) and stroke-associated pneumonia (SAP) in acute ischemic stroke (AIS) patients. Methods: AIS patients were enrolled in two centers. The serum samples were collected within the first 24 h after admission, and HMGB1 levels were measured by enzyme-linked immunosorbent assay. Logistic regression models were used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) of SAP for HMGB1 concentrations. Restricted cubic splines (RCS) were performed to explore the shapes of the association between HMGB1 concentrations and SAP. Results: From January 2022 to May 2022, a total of 420 AIS patients were enrolled. Ninety-six (22.9%) patients develop SAP. The levels of HMGB1 in the SAP group were higher than those in the non-SAP group (p < 0.001). Using the first quartile of HMGB1 group as a reference, patients in the fourth quartile of HMGB1 group had the highest likelihood of experiencing SAP in the unadjusted model (OR = 3.687; 95% CI: 1.851−7.344), age- and sex-adjusted model (OR = 3.511; 95% CI: 1.725−7.147), and multivariable-adjusted model (OR = 2.701; 95% CI: 1.045−6.981). HMGB1 was also independently associated with SAP as a continuous variable in the unadjusted model (OR = 1.132; 95% CI: 1.069−1.199), age- and sex-adjusted model (OR = 1.131; 95% CI: 1.066−1.200), and multivariable-adjusted model (OR = 1.096; 95% CI: 1.011−1.188). RCS showed a linear association between HMGB1 and SAP (p for linear trend = 0.008) Conclusions: HMGB1 might be able to act as a potential biomarker of SAP in AIS patients.

Study on the characteristics of glycerides and phospholipids in human milk from Tibet.

The unique geographical characteristics and food culture of Tibet can affect the nutrition of human milk lipids. But little has been done in the comparison of the lipids between Tibet and other areas. This study gives in-depth analysis of the species, concentration and composition of lipid subclasses at the molecular level of the Tibetan human milk. There were averagely 132 ± 30 species of lipids, among which triglycerides (TAGs), phosphatidylethanolamine (PE) and sphingomyelin (SM) accounted for 79.78% of the total species number in the Tibetan human milk samples. The contents of TAG, SM, phosphatidylcholine (PC), and PE in the Tibetan human milk were 85.84%, 17.79%, 25.94% and 55.81% of those in the comparative human milk of China, respectively. The contents of TAGs and diglycerides (DAGs) with PUFAs in Tibetan human milk were significantly lower than those in the comparative group. However, the content and percentage of TAGs and DAGs with odd-chain saturated fatty acids were both higher in the Tibetan human milk than those in the comparative human milk. In total, 18 molecular species of lipids were downregulated and 5 ones were upregulated in the Tibetan human milk compared with those in the comparative human milk of China. The profile of lipids in the Tibetan human milk at the molecular level provided the scientific basis for maternal diet and supplemented the Chinese human milk lipids database.

A Non-Peptidic MAS1 Agonist AVE0991 Alleviates Hippocampal Synaptic Degeneration in Rats with Chronic Cerebral Hypoperfusion.

BACKGROUND: Chronic cerebral hypoperfusion (CCH) is a contributing factor for neurodegenerative diseases. As a recently identified heptapeptide of the brain renin-angiotensin system, angiotensin-(1-7) has been revealed to activate its receptor MAS1 and thus ameliorated cognitive impairments in rats with CCH. Since hippocampal synaptic degeneration represents an important pathological basis of cognitive deficits, we hypothesize that activating MAS1-mediated signaling may alleviate CCH-induced synaptic degeneration in the hippocampus. METHODS: In this study, we tested this hypothesis and uncovered the underlying mechanisms in a rat model of CCH induced by bilateral common carotid artery ligation surgery. At one week after the surgery, rats received a daily intraperitoneal vehicle injection or a non-peptidic MAS1 agonist AVE0991 for 8 weeks. During this procedure, Cerebral Blood Flow (CBF) was recorded. The levels of MAS1, amyloid-ß (Aß), neuroinflammatory cytokines, glial cell markers, and synaptophysin in the hippocampus were assessed at the end of the treatment period. RESULTS: We showed that AVE0991 significantly alleviated hippocampal synaptic degeneration in rats with CCH. This protection might be achieved by facilitating CBF recovery, reducing hippocampal Aß levels, and suppressing neuroinflammatory responses. CONCLUSION: These findings indicate that MAS1-mediated signaling may represent a novel therapeutic target for CCH-related neurodegenerative diseases.

Angiotensin-(1-7) Analogue AVE0991 Modulates Astrocyte-Mediated Neuroinflammation via lncRNA SNHG14/miR-223-3p/NLRP3 Pathway and Offers Neuroprotection in a Transgenic Mouse Model of Alzheimer's Disease.

OBJECTIVE: Emerging evidence suggests that brain angiotensin-(1-7) (Ang-(1-7)) deficiency contributes to the pathogenesis of Alzheimer's disease (AD). Meanwhile, our previous studies revealed that restoration of brain Ang-(1-7) levels provided neuroprotection by inhibition of inflammatory responses during AD progress. However, the potential molecular mechanisms by which Ang-(1-7) modulates neuroinflammation remain unclear. MATERIALS AND METHODS: APP/PS1 mice were injected intraperitoneally with AVE0991 (a nonpeptide analogue of Ang-(1-7)) once a day for 30 consecutive days. Cognitive functions, neuronal and synaptic integrity, and inflammation-related markers were assessed. Since astrocytes played a crucial role in AD-related neuroinflammation whilst long noncoding RNAs (lncRNAs) were reported to participate in modulating inflammatory responses, astrocytes of APP/PS1 mice were isolated for high-throughput lncRNA sequencing to identify the most differentially expressed lncRNA following AVE0991 treatment. Afterward, the downstream pathways of this lncRNA in the anti-inflammatory action of AVE0991 were investigated using primary astrocytes. RESULTS: AVE0991 rescued spatial cognitive impairments and alleviated neuronal and synaptic damage in APP/PS1 mice. The levels of Aß1-42 in the brain of APP/PS1 mice were not affected by AVE0991. By employing high-throughput lncRNA sequencing, our in vitro study demonstrated for the first time that AVE0991 suppressed astrocytic NLRP3 inflammasome-mediated neuroinflammation via a lncRNA SNHG14-dependent manner. SNHG14 acted as a sponge of miR-223-3p while NLRP3 represented a direct target of miR-223-3p in astrocytes. In addition, miR-223-3p participated in the AVE0991-induced suppression of astrocytic NLRP3 inflammasome. CONCLUSION: Our results suggest that Ang-(1-7) analogue AVE0991 inhibits astrocyte-mediated neuroinflammation via SNHG14/miR-223-3p/NLRP3 pathway and offers neuroprotection in APP/PS1 mice. These findings reveal the underlying mechanisms by which Ang-(1-7) inhibits neuroinflammation under AD condition and uncover the potential of its nonpeptide analogue AVE0991 in AD treatment.