PerfusiMem

Alzheimer's disease (AD) and vascular dementia (VaD) are two prevalent forms of dementia. VaD is linked to cerebrovascular lesions, such as those from white matter ischemia and chronic cerebral hypoperfusion, which can also occur in AD. Nitric oxide (NO) regulates cerebral blood flow (CBF) in the central nervous system. Memantine is an NMDA receptor antagonist approved for AD treatment. This study investigated the efficacy and molecular mechanism of MN-08, a novel memantine nitrate, in one VaD model (2VO) and two AD models (APP/PS1 mice and Aβ1-42-induced mice). MN-08 increased CBF, ameliorated cognitive and memory functions in VaD and AD, and was more effective than memantine. MN-08 increased the survival rate of CA1 neurons and mitigated white matter lesions and axonal damage. Moreover, MN-08 protected neurons from OGD-induced loss and promoted axonal outgrowth in the hippocampus by upregulating phosphorylated Akt (p-Akt), glycogen synthase kinase-3β (p-GSK3β), and high-molecular-weight neurofilaments (p-NFH). The beneficial effects of MN-08 were attenuated by carboxy-PTIO, a potent NO scavenger, suggesting that MN-08-derived NO may alleviate cognitive impairment from cerebral hypoperfusion. Taken together, our studies demonstrate that MN-08 is a promising therapeutic agent for the treatment of dementia including VaD and AD.

Sepsis is a life-threatening organ dysfunction with devastating consequences, prominent among which is lung damage. Memantine, an N-methyl-D-aspartic acid receptor (NMDAR) antagonist, is able to alleviate acute lung injury (ALI). Nitric oxide (NO) suppresses NLRP3 inflammasome activation against lipopolysaccharide (LPS)-induced septic shock. MN-08, a novel nitrate derivative of memantine, possesses both the ability to antagonize NMDAR and release NO. In the present study, we aimed to investigate the protective effects of MN-08 against LPS-induced systemic inflammation and septic lung injury in mice, and to explore the underlying mechanisms of MN-08 in LPS-induced mice and THP-1 macrophages. MN-08 significantly increased the survival rate of septic mice, alleviated LPS-induced sepsis in mice via improving systemic inflammatory response syndrome and immune dysfunction, and attenuated pulmonary injury and inflammatory infiltration. More importantly, the therapeutic benefit of MN-08 for sepsis was greater than that of memantine and dexamethasone. Mechanistically, MN-08 exerted anti-inflammatory activity through inhibiting nuclear translocation of NF-κB, activation of the MAPK signaling pathway and the signaling transduction of STAT3/NF-κB. In addition, MN-08 suppressed NLRP3 inflammasome activation. Taken together, our studies demonstrate that MN-08 may be a promising therapeutic agent for sepsis-induced acute lung injury.