Effects of ML351 and tissue plasminogen activator combination therapy in a rat model of focal embolic stroke

Abstract

Thrombolytic stroke therapy with tissue plasminogen activator (tPA) is limited by risks of hemorrhagic transformation (HT). We have reported that a new 12/15-lipoxygenase (12/15-LOX) inhibitor ML351 reduced tPA related HT in mice subjected to experimental stroke under anticoagulation. In this study, we asked whether ML351 can ameliorate tPA induced HT in an embolic stroke model. Rats were subjected to embolic middle cerebral artery occlusion with 2 or 3 hr ischemia and tPA infusion, with or without ML351. Regional cerebral blood flow was monitored 2 hr after ischemia and continuously monitored for 1 hr after treatment for determining reperfusion.Hemoglobin was determined in brain homogenates and infarct volume was quantified at 24 hr after stroke.12/15-LOX, cluster of differentiation 68(CD68), immunoglobulin G (IgG), and tight junction proteins expression was detected by immunohistochemistry. ML351 significantly reduced tPA related hemorrhage after stroke without affecting its thrombolytic efficacy. ML351 also reduced blood-brain barrier disruption and improved preservation of junction proteins. ML351 and tPA combination improved neurological deficit of rats even though ML351 did not further reduce the infarct volume compared to tPA alone treated animals. Pro-inflammatory cytokines were suppressed by ML351 both in vivo and in vitro experiments. We further showed that ML351 suppressed the expression of c-Jun-N-terminal kinase (JNK) in brains and microglia cultures, whereas exogenous 12-HETE attenuated this effect in vitro. In conclusion, ML351 and tPA combination therapy is beneficial in ameliorating HT after ischemic stroke. This protective effect is probably because of 12/15-LOX inhibition and suppression of JNK-mediated microglia/macrophage activation.

Efficacy and safety of intravenous tenecteplase compared to alteplase before mechanical thrombectomy in acute ischemic stroke: a meta-analysis

“…Additionally, the absence of data on antiplatelet use during or after MT could also impact ICH rates. As a potential mechanism, ALT might elevate pro-inflammatory signals in the ischemic brain, thereby contributing to ICH via blood–brain barrier disruption [ 37 ]. The occurrence of ICH remains a significant concern in ALT treated AIS patients [ 38 ].…”

Progress of Ferroptosis in Ischemic Stroke and Therapeutic Targets

“…In the mice model of ischemic brain injury, ML351 combined with tPA relieved BBB destruction and neurologic impairment. The above effect occurred due to the fact that this treatment inhibited 12/15-LOX and activated the JNK signaling pathway to reverse the substantial increase of LPO product 12-HETE (Cheng et al 2021 ). At the same time, ML351 not only has good nanoscale titer and higher IC 50 , but also has better selectivity for 12/15-LOX than other isoenzymes (Rai et al 2010 ).…”

Changes in microglia during drug treatment of stroke

“…Matrix metalloproteinases (MMPs) Promoting activation and migration of astrocytes and microglia after cerebral ischemia [25] XQ-1H Regulation of pro/anti-inflammatory microglia polarization balance via the PPARγ pathway [26] Celastrol Decreasing OGD-induced inflammatory cytokine expression through IL-33/ST2 axis-mediated polarization of M2 microglia/macrophages [27] Ginkgo biloba extract Decreasing microglial cell-secreted inflammatory factor expression [28] 12/15-lipoxygenase (12/15-LOX) inhibitor ML351 Repression of proinflammatory cytokines, together with the expression of the c-Jun-n-terminal kinase [29] CXCR4 antagonist CX807 A reduction in glutamate-mediated neuronal loss and microglial activation and anti-inflammatory effects [30] 17β-estradiol A reduced number of activated microglia or infiltrating monocyte-derived macrophages selectively dampened the activation of the neuroinflammatory cascade [31] Administration of antithrombin (AT) AT has an anticoagulant effect on macrophage/microglial activation and a direct anti-inflammatory effect.…”