Jaiswal Shivani, Uniyal Ankit, Tiwari Vinod, Raja Ayyannan Senthil
Pharmaceutical Chemistry Research Laboratory II, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi - 221005, Uttar Pradesh, India.
Neuroscience and Pain Research Laboratory, Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (BHU), Varanasi 221005, Uttar Pradesh, India.
Bioorg Med Chem. 2022 Apr 15;60:116698. doi: 10.1016/j.bmc.2022.116698. Epub 2022 Mar 11.
Fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) are promising targets for neuropathic pain and other CNS disorders. Based on our previous lead compound SIH 3, we designed and synthesized a series of 4-methylsulfonylphenyl semicarbazones and evaluated for FAAH and MAGL inhibition properties. Most of the compounds showed potency towards both enzymes with leading FAAH selectivity. Compound (Z)-2-(2,6-dichlorobenzylidene)-N-(4-(methylsulfonyl)phenyl)hydrazine-1-carboxamide emerged as the lead inhibitor against both FAAH (IC = 11 nM) and MAGL (IC = 36 nM). The lead inhibitor inhibited FAAH by non-competitive mode, but showed a mixed-type inhibition against MAGL. Molecular docking study unveiled that the docked ligands bind favorably to the active sites of FAAH and MAGL. The lead inhibitor interacted with FAAH and MAGL via π-π stacking via phenyl ring and hydrogen bonding through sulfonyl oxygen atoms or amide NH. Moreover, the stability of docked complexes was rationalized by molecular simulation studies. PAMPA assay revealed that the lead compound is suitable for blood-brain penetration. The lead compound showed better cell viability in lipopolysaccharide-induced neurotoxicity assay in SH-SY5Y cell lines. Further, in-vivo experiments unveiled that dual inhibitor was safe up to 2000 mg/kg with no hepatotoxicity. The dual FAAH-MAGL inhibitor produced significant anti-nociceptive effect in the CCI model of neuropathic pain without altering locomotion activity. Lastly, the lead compound exhibited promising ex-vivo FAAH/MAGL inhibition activity at the dose of 10 mg/kg and 20 mg/kg. Thus, these findings suggest that the semicarbazone-based lead compound can be a potential template for the development of agents for neuropathic pain.
脂肪酸酰胺水解酶（FAAH）和单酰甘油脂肪酶（MAGL）是治疗神经性疼痛和其他中枢神经系统疾病的有前景的靶点。基于我们之前的先导化合物SIH 3，我们设计并合成了一系列4-甲基磺酰基苯基氨基脲，并评估了它们对FAAH和MAGL的抑制特性。大多数化合物对这两种酶都有活性，且对FAAH具有选择性优势。化合物（Z）-2-（2,6-二氯亚苄基）-N-（4-（甲基磺酰基）苯基）肼-1-甲酰胺成为对FAAH（IC = 11 nM）和MAGL（IC = 36 nM）均有效的先导抑制剂。该先导抑制剂以非竞争性模式抑制FAAH，但对MAGL表现出混合型抑制。分子对接研究表明，对接的配体与FAAH和MAGL的活性位点结合良好。先导抑制剂通过苯环的π-π堆积以及磺酰氧原子或酰胺NH的氢键与FAAH和MAGL相互作用。此外，通过分子模拟研究解释了对接复合物的稳定性。PAMPA分析表明，先导化合物适合血脑穿透。在脂多糖诱导的SH-SY5Y细胞系神经毒性试验中，先导化合物表现出更好的细胞活力。此外，体内实验表明，双抑制剂在高达2000 mg/kg的剂量下是安全的，且无肝毒性。双FAAH-MAGL抑制剂在神经性疼痛的CCI模型中产生了显著的抗伤害感受作用，而不改变运动活性。最后，先导化合物在10 mg/kg和20 mg/kg的剂量下表现出有前景的体外FAAH/MAGL抑制活性。因此，这些发现表明，基于氨基脲的先导化合物可能是开发用于神经性疼痛药物的潜在模板。
