The megaaortic syndrome: Progression of ascending aortic aneurysm or a disease of distinct origin?

Current understanding of macrophages in intracranial aneurysm: relevant etiological manifestations, signaling modulation and therapeutic strategies

Macrophages activation and inflammatory response play crucial roles in intracranial aneurysm (IA) formation and progression. The outcome of ruptured IA is considerably poor, and the mechanisms that trigger IA progression and rupture remain to be clarified, thereby developing effective therapy to prevent subarachnoid hemorrhage (SAH) become difficult. Recently, climbing evidences have been expanding our understanding of the macrophages relevant IA pathogenesis, such as immune cells population, inflammatory activation, intra-/inter-cellular signaling transductions and drug administration responses. Crosstalk between macrophages disorder, inflammation and cellular signaling transduction aggravates the devastating consequences of IA. Illustrating the pros and cons mechanisms of macrophages in IA progression are expected to achieve more efficient treatment interventions. In this review, we summarized the current advanced knowledge of macrophages activation, infiltration, polarization and inflammatory responses in IA occurrence and development, as well as the most relevant NF-κB, signal transducer and activator of transcription 1 (STAT1) and Toll-Like Receptor 4 (TLR4) regulatory signaling modulation. The understanding of macrophages regulatory mechanisms is important for IA patients' clinical outcomes. Gaining insight into the macrophages regulation potentially contributes to more precise IA interventions and will also greatly facilitate the development of novel medical therapy.

Primary Human Fibroblasts in Culture Switch to a Myofibroblast-Like Phenotype Independently of TGF Beta

Fibroblasts are the prevalent cell type and main source for extracellular matrix (ECM) in connective tissue. Depending on their origin, fibroblasts play a central role in non-pathological tissue remodeling and disease like fibrosis. This study examined the effect of established culture conditions of primary human fibroblasts, from different origins on the myofibroblast-like phenotype formation. We isolated primary human fibroblasts from aortic adventitia, lung, juvenile- and adult skin and investigated the expression levels of CD90, alpha smooth muscle actin (αSMA) and procollagen I under different concentrations of fetal calf serum (FCS) and ascorbic acid (AA) in culture media by immunoblot and immunofluorescence assays. Furthermore, we determined the viability using XTT and migration/wound healing in scratch assays. Collagen 1 secretion was quantified by specific ELISA. Primary human fibroblasts show in part a myofibroblast-like phenotype even without addition of FCS. Supplemented AA reduces migration of cultured fibroblasts with no or low concentrations of FCS. Furthermore, AA and higher concentrations of FCS in culture media lead to higher levels of collagen 1 secretion instead of procollagen I accumulation. This study provides evidence for a partial switch of primary human fibroblasts of different origin to a myofibroblast-like phenotype under common culture conditions.