Age potentiates neurodegeneration and impairs recovery from spinal cord injury (SCI). Previously, we observed that age alters the balance of destructive (M1) and protective (M2) macrophages, however, the age-related pathophysiology in SCI is poorly understood. NADPH oxidase (NOX) contributes to reactive oxygen species (ROS)-mediated damage and macrophage activation in neurotrauma. Further, NOX/ROS increase with CNS age. Here, we found significantly higher ROS generation in 14 vs. 4-month-old (MO) mice after contusion SCI. Notably, NOX2 increased in 14 MO ROS-producing macrophages suggesting that macrophages and NOX contribute to SCI oxidative stress. Indicators of lipid peroxidation, a downstream cytotoxic effect of ROS accumulation, were significantly higher in 14 vs. 4 MO SCI mice. We also detected a higher percentage of ROS-producing M2 (Arginase-1-positive) macrophages in 14 vs. 4 MO mice, a previously unreported SCI phenotype, and increased M1 (CD16/32-positive) macrophages with age. Thus, NOX and ROS are age-related mediators of SCI pathophysiology and normally protective M2 macrophages may potentiate secondary injury through ROS generation in the aged injured spinal cord.
Exenatide added to maximally effective doses of SU or SU plus MET resulted in a sustained reduction in HbA(1c) and a progressive reduction in weight over 1 1/2 years.
Matrix metalloproteinases (MMPs) have been regarded as major critical molecules assisting tumor cells during metastasis, for excessive ECM (ECM) degradation, and cancer cell invasion. In the present study, in vitro and in vivo assays were employed to examine the inhibitory effects of kaempferol, a natural polyphenol of flavonoid family, on tumor metastasis. Data showed that kaempferol could inhibit adhesion, migration, and invasion of MDA-MB-231 human breast carcinoma cells. Moreover, kaempferol led to the reduced activity and expression of MMP-2 and MMP-9, which were detected by gelatin zymography, real-time PCR, and western blot analysis, respectively. Further elucidation of the mechanism revealed that kaempferol treatment inhibited the activation of transcription factor activator protein-1 (AP-1) and MAPK signaling pathway. Moreover, kaempferol repressed phorbol-12-myristate-13-acetate (PMA)-induced MMP-9 expression and activity through suppressing the translocation of protein kinase Cδ (PKCδ) and MAPK signaling pathway. Our results also indicated that kaempferol could block the lung metastasis of B16F10 murine melanoma cells as well as the expression of MMP-9 in vivo. Taken together, these results demonstrated that kaempferol could inhibit cancer cell invasion through blocking the PKCδ/MAPK/AP-1 cascade and subsequent MMP-9 expression and its activity. Therefore, kaempferol might act as a therapeutic potential candidate for cancer metastasis.
Salvianolic acid B (SB) is an antioxidant derived from Salvia militarize, and is one of the most widely used herbs in traditional Chinese medicine. SB is a potent antioxidant that has been well documented as a scavenger of oxygen free radicals, and has been used for the prevention and treatment of atherosclerosis-associated disorders. To explore its potential therapeutic effects in treating radiation damage, in this study, mice were treated with SB at different doses of 5, 12.5 and 20 mg/kg, subsequent to receiving γ-irradiation. The effects of SB on peripheral blood, bone marrow nucleated cells, spleen and thymus indices, and oxidation resistance were evaluated in both radiated mice and control groups. The results indicated that SB significantly increased the counts of peripheral white blood cells, red blood cells and platelets. The number of nucleated cells in the bone marrow and the level of protein increased as well. In addition, improved spleen and thymus indices in the bone marrow were observed. SB treatment additionally reversed the deterioration of both the thymus and spleen indices, which is associated with increased serum superoxide dismutase activity and decreasing malondialdehyde levels via nuclear factor (erythroid-derived 2)-like 2 protein/BTB and CNC homology 1 mediated antioxidant effect. Furthermore, ROS levels and Bax protein expression were also suppressed by SB. The data suggested that SB is effective in protecting mice from γ-radiation injury, and could potentially be applicable for clinical use. Notably, the present study identified a promising candidate drug for enhancing the hematopoietic and immune systems.
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