Exosomal miR-23b from bone marrow mesenchymal stem cells alleviates oxidative stress and pyroptosis after intracerebral hemorrhage

Our previous studies showed that miR-23b was downregulated in patients with intracerebral hemorrhage(ICH). This indicates that miR-23b may be closely related to the patho-physiological mechanism of ICH, but this hypothesis lacks direct evidence. In this study, we established rat models of ICH by injecting collagenase Ⅶ into the right basal ganglia and treating them with an injection of bone marrow mesenchymal stem cell(BMSC)-derived exosomal miR-23b via the tail vein. We found that edema in the rat brain was markedly reduced and rat behaviors were improved after BMSC exosomal miR-23b injection compared with those in the ICH groups. Additionally, exosomal miR-23b was transported to the microglia/macrophages, thereby reducing oxidative stress and pyroptosis after ICH. We also used hemin to mimic ICH conditions in vitro. We found that phosphatase and tensin homolog deleted on chromosome 10(PTEN) was the downstream target gene of miR-23b, and exosomal miR-23b exhibited antioxidant effects by regulating the PTEN/Nrf2 pathway. Moreover, miR-23b reduced PTEN binding to NOD-like receptor family pyrin domain containing 3(NLRP3) and NLRP3 inflammasome activation, thereby decreasing the NLRP3-dependent pyroptosis level. These findings suggest that BMSC-derived exosomal miR-23b exhibits antioxidant effects through inhibiting PTEN and alleviating NLRP3 inflammasome-mediated pyroptosis, thereby promoting neurologic function recovery in rats with ICH.

Synthesis,Structure and Magnetic Behavior of a Novel Series of Trinuclear Windwheel Complexes

A new family of trinuclear windwheel complexes with molecular formula [M^(II)_(3)(tpa)_(3)(μ-ttc)](ClO_(4))_(3)·n(sol) (ttc = 1,3,5-triazine-2,4,6-trithiol;tpa = tris(2-pyridylmethyl)amine;M = Mn,n = 2,sol = CH_(3)CN,1;M = Co,n = 1,sol = CH_(3)CN,2;M = Ni,n = 0,3) were synthesized and characterized.Single-crystal X-ray diffraction revealed that three metal centers in 1—3 are connected by ttc bridge,forming a regular triangular MII3 core.Each metal center is bonded by chelating S,N atoms from ttc and by N atoms from tpa.Magnetic studies showed that 1—3 displayed antiferromagnetic behavior and further gave the easy-axis anisotropy (D = −0.77 cm^(−1) for 1 and −8.13 cm^(−1) for 2) and easy-plane anisotropy (D = 5.08 cm^(−1) for 3).Moreover,2 exhibited field-induced slow magnetic relaxation behavior and their effective energy barriers were roughly evaluated Ueff = 6.9 K.

Magnetic resonance imaging manifestations of cerebral small vessel disease:automated quantification and clinical application

The common cerebral small vessel disease(CSVD)neuroimaging features visible on conventional structural magnetic resonance imaging include recent small subcortical infarcts,lacunes,white matter hyperintensities,perivascular spaces,microbleeds,and brain atrophy.The CSVD neuroimaging features have shared and distinct clinical consequences,and the automatic quantification methods for these features are increasingly used in research and clinical settings.This review article explores the recent progress in CSVD neuroimaging feature quantification and provides an overview of the clinical consequences of these CSVD features as well as the possibilities of using these features as endpoints in clinical trials.The added value of CSVD neuroimaging quantification is also discussed for researches focused on the mechanism of CSVD and the prognosis in subjects with CSVD.