Somatic BrafV600E mutation in the cerebral endothelium induces brain arteriovenous malformations.

Current treatments of brain arteriovenous malformation (BAVM) are associated with considerable risks and at times incomplete efficacy. Therefore, a clinically consistent animal model of BAVM is urgently needed to investigate its underlying biological mechanisms and develop innovative treatment strategies. Notably, existing mouse models have limited utility due to heterogenous and untypical phenotypes of AVM lesions. Here we developed a novel mouse model of sporadic BAVM that is consistent with clinical manifestations in humans. Mice with BrafV600E mutations in brain ECs developed BAVM closely resembled that of human lesions. This strategy successfully induced BAVMs in mice across different age groups and within various brain regions. Pathological features of BAVM were primarily dilated blood vessels with reduced vascular wall stability, accompanied by spontaneous hemorrhage and neuroinflammation. Single-cell sequencing revealed differentially expressed genes that were related to the cytoskeleton, cell motility, and intercellular junctions. Early administration of Dabrafenib was found to be effective in slowing the progression of BAVMs; however, its efficacy in treating established BAVM lesions remained uncertain. Taken together, our proposed approach successfully induced BAVM that closely resembled human BAVM lesions in mice, rendering the model suitable for investigating the pathogenesis of BAVM and assessing potential therapeutic strategies.

Apelin ameliorated acute heart failure via inhibiting endoplasmic reticulum stress in rabbits.

This study aimed to investigate whether inhibition of endoplasmic reticulum stress (ERS) mediated the ameliorative effect of apelin on acute heart failure (AHF). Rabbit model of AHF was induced by sodium pentobarbital. Cardiac dysfunction and injury were detected in the rabbit models of AHF, including impaired hemodynamic parameters and increased levels of CK-MB and cTnI. Apelin treatment dramatically improved cardiac impairment caused by AHF. ERS, indexed by increased GRP78, CHOP, and cleaved-caspase12 protein levels, was simultaneously attenuated by apelin. Apelin also could ameliorate increased protein levels of cleaved-caspase3 and Bax, and improved decreased protein levels of Bcl-2. Two common ERS stimulators, tunicamycin (Tm) and dithiothreitol (DTT) blocked the ameliorative effect of apelin on AHF. Phosphorylated Akt levels increased after apelin treatment in the rabbit models of AHF. The Akt signaling inhibitors wortmannin and LY294002 could block the cardioprotective effect of apelin, which could be relieved by ERS inhibitor 4-phenyl butyric acid (4-PBA). The aforementioned beneficial effects of apelin could all be blocked by APJ receptor antagonist F13A. 4-PBA and SC79, an Akt activator, can restore the ameliorative effect of apelin on AHF blocked by F13A. Apelin treatment dramatically ameliorated cardiac impairment caused by AHF, which might be mediated by APJ/Akt/ERS signaling pathway. These results will shed new light on AHF therapy.

The natural course, treatment outcomes, and long-term prognosis of cervical spinal cord arteriovenous shunts.

OBJECTIVE: The highly intricate nature of the cervical spinal cord can cause arteriovenous shunts in these segments that may be associated with heightened clinical risks and treatment complexities. In this article, the authors aimed to provide a comprehensive analysis of the detailed natural course, treatment, and clinical outcomes of cervical spinal cord arteriovenous shunts (SCAVSs) based on the largest cohort to date. METHODS: Two hundred forty consecutive patients were included. Data on clinical presentation, angioarchitecture, treatment, and follow-up were retrospectively reviewed. RESULTS: The cohort demonstrated a greater prevalence of acute onset (63.3% vs 36.7%). Spontaneous recovery was observed in 63.7% of patients after onset, with a significantly elevated recovery rate observed among patients experiencing acute onset (72.4% vs 48.9%, p < 0.001). The risks of acute and gradual clinical deterioration after onset was 11.9%/year and 13.4%/year, respectively. Microsurgery was performed in 39.6% of patients, while the remaining 60.4% exclusively underwent embolization. The complete obliteration rate was 65.3% after microsurgery and 21.4% after embolization. The rate of treatment-related deterioration was 14.7% after microsurgery and 6.2% after embolization. After partial treatment, the acute and gradual deterioration rates were 4.1%/year and 6.6%/year, respectively. Lack of spontaneous recovery after onset was an independent predictor of embolization-related deterioration (OR 17.905, p = 0.007) and long-term gradual deterioration after partial treatment (HR 2.325, p = 0.021). After a median follow-up period of 32.55 months, prognosis was unfavorable in 16.7% of patients, with the sole independent risk factor being the absence of spontaneous recovery after onset (OR 2.476, p = 0.018). CONCLUSIONS: The outcomes of patients with cervical SCAVS were generally favorable, even in patients with only partial obliteration of the lesions. However, patients who did not show a trend toward spontaneous recovery after onset had a significantly elevated risk of unfavorable prognosis, highlighting the need for prompt clinical intervention.