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Abstract Retinopathy of prematurity (ROP) is an eye disease that causes blindness due to delayed vascular growth, retinal ischemia, and resulting abnormal angiogenesis. Nonselective β-antagonist propranolol is in clinical trials for the treatment of ROP due to its effect of reducing VEGF expression and inhibiting retinal angiogenesis in oxygen-induced ROP models (OIR), but the mechanism by which propranolol acts on ROP vessels is still unclear. In the present study, we have focused on the effect of propranolol on pericyte survival and vascular permeability. We demonstrated that propranolol increases pericyte apoptosis more sensitively than endothelial cells (ECs), thereby weakening EC tight junctions to increase endothelial permeability in co-cultures of pericytes and ECs. Mechanistically, pericyte apoptosis by propranolol was due to the inhibition of Akt signaling pathway. We also demonstrated that propranolol increases pericyte loss and vascular permeability of retinal vessels in a mouse model of OIR. These results suggest that propranolol may be negative for blood vessels in retinas of OIR, and that the efficacy of propranolol for the treatment of ROP needs to be more thoroughly verified. Highlights • Propranolol increased pericyte apoptosis more sensitively than endothelial cells. • Propranolol weakened the tight junction of endothelial cells in co-cultures of pericytes and endothelial cells. • Propranolol increased endothelial permeability in vitro and vascular permeability in OIR retinas of mice in vivo. [ABSTRACT FROM AUTHOR]

Angiogenesis, a fundamental process in human physiology and pathology, has attracted considerable attention owing to its potential as a therapeutic strategy. Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are deemed major mediators of angiogenesis. To date, inhibition of the VEGF-A/VEGFR-2 axis has been an effective strategy employed in the development of anticancer drugs. However, some limitations, such as low efficacy and side effects, need to be addressed. Several drug candidates have been discovered, including small molecule compounds, recombinant proteins, and oligosaccharides. In this review, we focus on human oligosaccharides as modulators of angiogenesis. In particular, sialylated human milk oligosaccharides (HMOs) play a significant role in the inhibition of VEGFR-2-mediated angiogenesis. We discuss the structural features concerning the interaction between sialylated HMOs and VEGFR-2 as a molecular mechanism of anti-angiogenesis modulation and its effectiveness in vivo experiments. In the current state, extensive clinical trials are required to develop a novel VEGFR-2 inhibitor from sialylated HMOs. [ABSTRACT FROM AUTHOR]

For centuries, Fructus ligustri lucidi (FLL; the fruit of Ligustrum lucidum Aiton or Ligustrum japonicum Thunb.) has been commonly used in traditional Chinese medicine for treating hepatitis and aging-related symptoms and in traditional Korean medicine to detoxify kidneys and the liver. Pharmacological research has shown FLL has antioxidant, anti-inflammatory, anticancer, anti-osteoporosis, and hepatoprotective activities. This study was undertaken to investigate the effects of FLL extract (FLLE) on neuroinflammation. After setting a non-toxic concentration using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide] assay data, we investigated the effects of FLLE using Western blotting, cell migration, enzyme-linked immunosorbent assay, a nitric oxide (NO) assay, and immunofluorescence staining in lipopolysaccharide (LPS)-stimulated murine BV2 microglial cells. FLLE was non-toxic to BV2 cells up to a concentration of 500 μg/mL and concentration-dependently inhibited the production of NO and prostaglandin E2 and the protein levels of inducible nitric oxide synthase and cyclooxygenase-2 under LPS-induced inflammatory conditions. It also inhibited the secretion of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Furthermore, FLLE pretreatment attenuated LPS-induced increases of CD68 (a marker of microglia activation) and suppressed the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) signaling pathways in LPS-stimulated BV2 cells, and significantly increased heme oxygenase (HO)-1 levels. FLLE also reduced the LPS-induced increase in the migratory ability of BV2 cells and the phosphorylation of vascular endothelial growth factor receptor 1. Collectively, FLLE effectively inhibited inflammatory response by suppressing the MAPK and NF-κB signaling pathways and inducing HO-1 in LPS-stimulated BV2 microglial cells. Our findings provide a scientific basis for further study of FLL as a candidate for preventing or alleviating neuroinflammation. [ABSTRACT FROM AUTHOR]

Abstract Ethnopharmacological relevance Dipsaci Radix, which is the dried root of Dipsacus asperoides C. Y. Cheng and T. M. Ai (Dipsacaceae), is used to treat back pain and blood stasis syndrome in Korean traditional medicine. Aim of the study To understand the mechanisms responsible for the pharmacological activities of D. asperoides , we investigated the inhibitory effect of D. asperoides on lipopolysaccharide (LPS)-induced inflammation in mouse macrophages RAW 264.7 cells. Materials and methods Aqueous extract of D. asperoides (AEDA) was prepared by boiling D. asperoides in water and then administered to LPS treated RAW 264.7 cells. Cell viabilities were measured using an MTT assay, and protein levels were determined by western blotting. The ROS scavenging activity of AEDA was measured using a DCFH-DA assay and levels of nitric oxide (NO) were determined using a NO assay. The nuclear translocations of NF-κB and Nrf2 were investigated immunocytochemically, and pro-inflammatory cytokines in supernatant were evaluated by ELISA. Results Treatment with AEDA suppressed the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophages. AEDA also reduced ROS, pro-inflammatory cytokine (IL-6 and IL-1β) levels, and iNOS-derived NO and COX-2-derived prostaglandin E2 release to medium, and suppressed the phosphorylation and degradation of IκB and the activation of NF-κB in macrophages. Furthermore, treatment with AEDA inhibited the ERK1/2 pathway but not the JNK or p38 MAPK pathways. In addition, AEDA significantly promoted Nrf2 translocation from cytoplasm to nucleus and up-regulated the expression of HO-1. Conclusion These results suggest that AEDA has anti-inflammatory and anti-oxidative effects through the inhibition of NF-κB and ERK1/2 and the activation of Nrf2/HO-1 in macrophages. Graphical abstract fx1 [ABSTRACT FROM AUTHOR]

Despite the advent of oral phosphodiesterase-5 inhibitors, curative treatment for erectile dysfunction (ED) remains unavailable. Recently, the link between ED and cardiovascular disease was unveiled and the main etiology of ED was found to be vasculogenic. Therefore, neovascularization is a promising strategy for curing ED. Angiopoietin-1 (Ang1) is an angiogenic growth factor that promotes the generation of stable and functional vasculature. Here, we demonstrate that local delivery of the soluble, stable, and potent Ang1 variant, COMP-Ang1 gene or protein, into the penises of hypercholesterolemic mice increases cavernous angiogenesis, eNOS phosphorylation, and cGMP expression, resulting in full recovery of erectile function and cavernous blood flow up to 8 weeks after treatment. COMP-Ang1-induced promotion of cavernous angiogenesis and erectile function was abolished in Nos3-/- mice and in the presence of the NOS inhibitor, L-NAME. COMP-Ang1 also restored the integrity of endothelial cell-cell junction by down-regulating the expression of histone deacetylase 2 in the penis of hypercholesterolemic mice and in primary cultured mouse cavernous endothelial cells. These findings constitute a new paradigm toward curative treatment of both cavernous angiopathy and ED. [ABSTRACT FROM AUTHOR]