A new Keap1–Nrf2 protein–protein interaction (PPI) inhibitor ZJ01 was identified from our compound library by fluorescence polarization assay, surface plasmon resonance, molecular docking and molecular dynamics simulation. ZJ01 could in vitro trigger Nrf2 nuclear translocation, subsequently resulting in increased mRNA levels of Nrf2 target genes HO-1 and NQO1. Meanwhile, ZJ01 suppressed LPS-induced production of ROS and the mRNA levels of pro-inflammatory cytokines TNF-α, IL-1β and IL-6 in H9c2 cardiac cells. Moreover, in an in vivo mouse model of septic cardiomyopathy induced by intraperitoneal injection of lipopolysaccharide, ZJ01 demonstrated a cytoprotective effect, upregulated Nrf2 protein nuclear accumulation, and remarkably suppressed the abovementioned cytokine levels in cardiomyocytes. The results presented herein provided a novel chemotype for the development of direct Keap1–Nrf2 PPI inhibitors and suggested that compound ZJ01 is a promising drug lead for septic cardiomyopathy treatment. ZJ01 was identified as a new Keap1–Nrf2 PPI inhibitor and drug lead for septic cardiomyopathy treatment by in vitro and in vivo experiments. Graphical Abstract
Although adipose‐derived mesenchymal stem cells (ADMSCs) isolated from patients’ fat are considered as the most important autologous stem cells for tissue repair, significant difficulties in the neural differentiation of ADMSCs still impede stem cell therapy for neurodegenerative diseases. Herein, a wireless‐electrical stimulation method is proposed to direct the neural differentiation of ADMSCs based on the electromagnetic effect using a graphene film as a conductive scaffold. By placing a rotating magnet on the top of a culture system without any inducer, the ADMSCs cultured on graphene differentiate into functional neurons within 15 days. As a conductive biodegradable nanomaterial, graphene film acts as a wireless electrical signal generator driven by the electromagnetic induction, and millivolt‐level voltage generated in situ provokes ADMSCs to differentiate into neurons, proved by morphological variation, extremely high levels of neuron‐specific genes, and proteins. Most importantly, Ca2+ intracellular influx is observed in these ADMSC‐derived neurons once exposure to neurotransmitters, indicating that these cells are functional neurons. This research enhances stem cell therapy for neurodegenerative diseases using autologous ADMSCs and overcomes the lack of neural stem cells. This nanostructure‐mediated physical‐signal simulation method is inexpensive, safe, and localized, and has a significant impact on neural regeneration.
Oxidized low-density lipoprotein (oxLDL)-induced endothelium injury promotes the development of atherosclerosis. It has been reported that homoplantaginin, a flavonoid glycoside from the traditional Chinese medicine Salvia plebeia R. Br., protected vascular endothelial cells by inhibiting inflammation. However, it is undetermined whether homoplantaginin affects atherosclerosis. In this study, we evaluated the effect of homoplantaginin and its derivative dihydrohomoplantagin on oxLDL-induced endothelial cell injury and atherosclerosis in apoE-/- mice. Our results showedthat both dihydrohomoplantagin and homoplantaginin inhibited apoptosis and the increased level of ICAM-1 and VCAM-1 in oxLDL-stimulated HUVECs and the plaque endothelium of apoE-/- mice. Additionally, both of them restricted atherosclerosis development of apoE-/- mice. Mechanistic studies showed that oxLDL-induced the increase in ROS production, phosphorylation of ERK and nuclear translocation of NF-κB in HUVECs was significantly inhibited by the compounds. Meanwhile, these two compounds promoted Nrf2 nuclear translocation and increased the anti-oxidation downstream HO-1 protein level in HUVECs and plaque endothelium. Notably, knockdown of Nrf2 by siRNA abolished the cell protective effects of compounds and antagonized the inhibition effects of them on ROS production and NF-κB activation in oxLDL-stimulated HUVECs. Collectively, dihydrohomoplantagin and homoplantaginin protected VECs by activating Nrf2 and thus inhibited atherosclerosis in apoE-/- mice.
Oxidized low-density lipoprotein (ox-LDL)-induced oxidative injury in vascular endothelial cells is crucial for the progression of cardiovascular diseases, including atherosclerosis. Several flavonoids have been shown cardiovascular protective effects. Recently, our research group confirmed that the novel flavonoids isolated from the deep-sea-derived fungus Arthrinium sp., 2,3,4,6,8-pentahydroxy-1-methylxanthone (compound 1) and arthone C (compound 2) effectively scavenged ROS in vitro. In this study, we further investigated whether these compounds could protect against ox-LDL-induced oxidative injury in endothelial cells and the underlying mechanisms. Our results showed that compounds 1 and 2 inhibited ox-LDL-induced apoptosis and adhesion factors expression in human umbilical vein vascular endothelial cells (HUVECs). Mechanistic studies showed that these compounds significantly inhibited the ROS level increase and the NF-κB nuclear translocation induced by ox-LDL. Moreover, compounds 1 and 2 activated the Nrf2 to transfer into nuclei and increased the expression of its downstream antioxidant gene HO-1 by inducing the phosphorylation of AKT in HUVECs. Importantly, the AKT inhibitor MK-2206 2HCl or knockdown of Nrf2 by RNA interference attenuated the inhibition effects of these compounds on ox-LDL-induced apoptosis in HUVECs. Meanwhile, knockdown of Nrf2 abolished the effects of the compounds on ox-LDL-induced ROS level increase and the translocation of NF-κB to nuclei. Collectively, the data showed that compounds 1 and 2 protected endothelial cells against ox-LDL-induced oxidative stress through activating the AKT/Nrf2/HO-1 pathway. Our study provides new strategies for the design of lead compounds for related cardiovascular diseases treatment.
5 July 2023 in European Journal of Medicinal Chemistry