Studies on the enantiomers of ZJM-289: synthesis and biological evaluation of antiplatelet, antithrombotic and neuroprotective activities

From Seeds of Apium graveolens Linn. to a Cerebral Ischemia Medicine: The Long Journey of 3-n-Butylphthalide

3-n-Butylphthalide (NBP) as well as its derivatives and analogues (NBPs), in racemic or enantiomerically pure forms, possess potent and diverse pharmacological properties and have shown a great potential therapeutic interest for many human conditions, especially for cerebral ischemia. This Perspective outlines the synthesis and therapeutic applications of NBPs.

Effect of dl-3-n-butylphthalide on infarction volume in animal models of ischemic stroke: A meta-analysis

BACKGROUND

Ischemic stroke is a frequently-occurring disease in the elderly and characterized by high morbidity and mortality. Dl-3-n-butylphthalide (NBP), a synthetic compound based on natural celery seeds, has potential therapeutic effects on cerebral ischemia, brain trauma, memory impairment, and epilepsy.

AIM

To evaluated the effect of NBP on infarct volume in experimental ischemic stroke.

METHODS

Twenty one relevant literatures were included from the PubMed, EMBASE, Web of Science, Chinese National Knowledge Infrastructure, VIP information database, and Wanfang database, and data on the effect of dl-3-n-butylphthalide on infarction volume in the middle cerebral artery occlusion model were extracted. Statistical analysis was performed using standard mean difference with random effects model of Revman 5.3.

RESULTS

The data of meta-analysis of the 21 studies had suggested that NBP reduced the cerebral infarction volume of middle cerebral artery occlusion model animals compared to the control group significantly [SMD: -3.97, 95%CI: -4.71 to -3.23, P < 0.01; heterogeneity: χ² = 59.09, df = 20 (P < 0.01); I² = 66 %].

CONCLUSION

NBP was effective in experimental ischemic stroke.

A Dual AMPK/Nrf2 Activator Reduces Brain Inflammation After Stroke by Enhancing Microglia M2 Polarization

AIMS

Microglia-mediated neuroinflammation plays an important role in focal ischemic stroke, a disorder with no effective therapeutic agents. Since microglial polarization to the M2 phenotype and reduction of oxidative stress are mediated through AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor 2 (Nrf2) activation, we assessed the dual therapeutic effect of AMPK and Nrf2 activation by a novel neuroprotectant HP-1c in the treatment of ischemic stroke.

RESULTS

We developed a novel class of hybrids (HP-1a-HP-1f) of telmisartan and 2-(1-hydroxypentyl)-benzoate (HPBA) as a ring-opening derivative of NBP. The most promising hybrid, HP-1c, exhibited more potent anti-inflammatory and neuroprotective effects in vitro and reduced brain infarct volume and improved neurological deficits in a rat model of transient focal cerebral ischemia when compared with telmisartan alone, NBP alone, or a combination of telmisartan and NBP. HP-1c had a therapeutic window of up to 24 h, ameliorated ischemic cerebral injury in permanent focal cerebral ischemia, and improved motor function. The beneficial effects of HP-1c in ischemic stroke were associated with microglial polarization to the M2 phenotype and reduced oxidative stress. HP-1c also shifted the M1/M2 polarization in a mouse neuroinflammatory model. The anti-inflammatory and anti-oxidative effects of HP-1c were associated with AMPK-Nrf2 pathway activation for neuroprotection. We showed that HP-1c penetrates the brain, has a plasma half-life of around 3.93 h, and has no toxicity in mice. Innovation and Conclusion: Our study results suggest that HP-1c, with dual AMPK- and Nrf2-activating properties, may have potential in further studies as a novel therapy for ischemic stroke. Antioxid. Redox Signal. 28, 141-163.

Discovery of a ring-opened derivative of 3-n-butylphthalide bearing NO/H2S-donating moieties as a potential anti-ischemic stroke agent

To search for novel anti-ischemic stroke agents with higher potency than a known drug 3-n-butylphthalide (NBP), a series of ring-opened derivatives of NBP bearing both nitric oxide (NO) and hydrogen sulfide (H2S)-donating moieties (NO/H2S-NBP) (8a-8o) were designed, synthesized, and biologically evaluated. The most active compound 8d was more potent than NBP and the corresponding H2S-NBP 10 or NO-NBP 13 in inhibition of the ADP-induced platelet aggregation in vitro. In addition, 8d produced moderate levels of NO and H2S, which could be beneficial for improving cardiovascular and cerebral circulation. More importantly, in a rat model of transient focal cerebral ischemia, oral treatment with 8d improved neurobehavioral function, reduced the infarct brain size and brain-water content, and enhanced the levels of brain antioxidant SOD, GSH and GSH-Px but diminished the level of oxidant MDA. These protective effects of 8d against the ischemia/reperfusion (I/R)-related brain damage were greater than that of NBP, suggesting that 8d may be a promising agent for further investigation.

Design, synthesis and biological evaluation of hydrogen sulfide releasing derivatives of 3-n-butylphthalide as potential antiplatelet and antithrombotic agents

In the present study, a series of hydrogen sulfide (H2S) releasing derivatives (8a–g and 9a–f) of 3-n-butylphthalide (NBP) were designed, synthesized and biologically evaluated. The most promising compound 8e significantly inhibited the adenosine diphosphate (ADP) and arachidonic acid (AA)-induced platelet aggregation in vitro, superior to NBP, ticlopidine hydrochloride and aspirin. Furthermore, 8e could slowly produce moderate levels of H2S in vitro, which could be beneficial for improving cardiovascular and cerebral circulation. Most importantly, 8e protected against the collagen and adrenaline induced thrombosis in mice, and exhibited greater antithrombotic activity than NBP and aspirin in rats. Overall, 8e could warrant further investigation for the treatment of thrombosis-related ischemic stroke.

Huang-Lian-Jie-Du-Decotion induced protective autophagy against the injury of cerebral ischemia/reperfusion via MAPK-mTOR signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du-Decotion (HLJDD, Hwangryun-Hae-Dok-Decotion in Japan), an ancient antipyretic and detoxifying traditional Chinese medicine formula, was reported to have protective effect on ischemic stroke.

AIM OF THE RESEARCH

To investigate the therapeutic effect of HLJDD on ischemic stroke and explore its mode of action.

MATERIAL AND METHODS

A model of ischemic stroke in the rat was established after transient middle cerebral artery occlusion (MCAO) followed by reperfusion. Rats were assigned randomly to groups of control, sham, transient ischemia/reperfusion (I/R), and three treatment groups by HLJDD at 2.5, 5.0, 10.0mg/kg. The neurological deficit, the cerebral infarct size, morphology abnormality, biochemical parameters were examined, and the levels of relevant proteins were determined by immunoblotting analysis to evaluate the protective effects of HLJDD on ischemic stroke and explore the underlying mechanism.

RESULTS

Compared with I/R group, HLJDD significantly ameliorated neurological deficit and histopathology changes, decreased infarct area, and restored the levels of biochemical indicators including nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), glutathione disulfide (GSSG), total superoxide dismutase (T-SOD), Cu/Zn-SOD, Mn-SOD and glutathione peroxidase (GSH-PX). HLJDD also notably elevated the levels of microtubule-associated protein 1 light chain 3 (LC3), Beclin-1, and other autophagy related genes (Atgs), promoted the activation of extracellular signal-regulated kinases (ERK), protein kinase B (Akt), 3-phosphoinositide-dependent kinase (PDK1), and inhibited the activation of mammalian target of rapamycin (mTOR), c-Jun N-terminal protein kinases (JNK), p38, phosphatase and tensin homolog (PTEN).

CONCLUSION

HLJDD showed neuroprotective effects on ischemic stroke, at least in part to the induced protective autophagy via the regulation of mitogen-activated protein kinase (MAPK) signals. This Akt-independent protective autophagy is favorable in the treatment of stroke, avoiding unfavorable side-effects associated with the inactivation of Akt. The efficacy of HLJDD on ischemic stroke and its safety warranted by its long-term clinical use in traditional Chinese medicine favored further study to develop HLJDD as an effective therapeutic agent to treat ischemic stroke.

Pharmacokinetics in Sprague-Dawley rats and Beagle dogs and in vitro metabolism of ZJM-289, a novel nitric dioxide donor

1. The aim was to evaluate the prodrug hypothesis by investigating the pharmacokinetics of ZJM-289 and its pharmacological metabolite 3-n-butylphthalide (NBP) in Sprague-Dawley rats and Beagle dogs following intravenous and intragastric administration of ZJM-289. The in vitro metabolic patterns in plasma and microsomal system were assessed to elucidate PK properties. 2. In rats, ZJM-289 was eliminated rapidly (t1/2 = 19.2 ± 3.85 min), along with the fast formation of NBP (formation rate constant ka = 0.29 ± 0.092 min(-1) for intravenous group, and ka = 0.16 ± 0.064 min(-1) for intragastric group), accounting for about 47.4 ± 4.0% of ZJM-289. Both ZJM-289 (t1/2 = 239 ± 70.4 min) and NBP (t1/2 = 249 ± 39.0 min) were depleted slowly in Beagle dogs, with NBP formation rate constant at 0.12 ± 0.052 min(-1) (ka = 0.15 ± 0.040 min(-1) for intragastric group). 3. In rat plasma, ZJM-289 was degraded rapidly (t1/2 = 24.3 ± 0.93 min) at 37 °C, but remained stable with almost no cleavage in dog and human plasma. In hepatic microsomes from rat, dog and human, the hydrolysis metabolites including the active metabolite NBP (M5), and their subsequent hydroxylation and conjugate metabolite, were all detected but varied greatly in the quantities. 4. The findings testified the prodrug design hypothesis that ZJM-289 could be hydrolyzed to NBP. The pharmacokinetic profiles in both rats and dogs brought useful information in the pharmacokinetics prediction in human.

Novel hybrids of optically active ring-opened 3-n-butylphthalide derivative and isosorbide as potential anti-ischemic stroke agents

In search of novel anti-ischemic stroke agents with higher potency than a known drug 3-n-butylphthalide (NBP), a series of hybrids ((S)- and (R)-5a-f) from optically active ring-opened NBP derivative and isosorbide were synthesized for evaluating their anti-ischemic stroke activity. Compound (S)-5e displayed the strongest activity in inhibiting the adenosine diphosphate (ADP) and arachidonic acid (AA)-induced platelet aggregation in vitro, with 10.0- and 8.4-fold more effectiveness than (S)-NBP, respectively. Furthermore, (S)-5e was stable in artificial gastrointestinal fluids and could penetrate the blood-brain barrier (BBB) with an appreciate lipid/water partition coefficient relative to (S)-NBP. More importantly, oral treatment with (S)-5e protected from acute thrombosis and inhibited the ischemia/reperfusion-related brain injury in animals. Our findings suggest that (S)-5e may be promising for further evaluation for the intervention of ischemic stroke.

Synthesis and biological evaluation of nitric oxide releasing derivatives of 6-amino-3-n-butylphthalide as potential antiplatelet agents

A series of novel nitric oxide releasing derivatives of 6-amino-3-n-butylphthalide were designed, synthesized and evaluated as potential antiplatelet agents. Compound 10b significantly inhibited the adenosine diphosphate (ADP)-induced platelet aggregation in vitro, superior to 6-amino-3-n-butylphthalide, 3-n-butylphthalide (NBP) and ticlopidine. Meanwhile 10b released moderate levels of NO, which could be beneficial for improving cardiovascular and cerebral circulation. Furthermore, 10b had an enhanced aqueous solubility relative to NBP. These findings may provide new insights into the development of novel antiplatelet agents for the treatment of thrombosis-related ischemic stroke.