Načrtovanje, sinteza in vrednotenje N-alkilpirolidin karbamatov kot zaviralcev holin esteraz in monoamin oksidaz

Mastnak-Sokolov, Peter (author), Gobec, Stanislav (mentor), Košak, Urban (comentor)

Nabor odobrenih zdravil za (simptomatsko) zdravljenje Alzheimerjeve bolezni (AB) in njihova učinkovitost sta razmeroma omejena, zato je potreba po razvoju novih učinkovin za terapijo te nevrodegenerativne bolezni izredno velika. Na tem področju so zelo zanimive molekule z delovanjem na več različnih tarč, udeleženih v kompleksni patofiziologiji AB. Dve izmed tarč potencialnih novih učinkovin za (simptomatsko) zdravljenje AB sta encima butirilholin esteraza (BChE) in monoamin oksidaza B (MAO-B) – izražanje obeh je v možganih bolnikov z AB povečano. Zaviranje BChE upočasni razgradnjo živčnega prenašalca acetilholina (ACh) in ublaži simptome AB brez holinergičnih neželenih učinkov, značilnih za zaviralce acetilholin esteraze (AChE). Zaviranje MAO-B zmanjša oksidativni stres, ki pospešuje nevrodegenerativne procese. Načrtovali in sintetizirali smo 30 novih N-alkilpirolidin karbamatov ter z encimskimi testi ovrednotili njihovo sposobnost zaviranja holin esteraz (ChE) in monoamin oksidaz (MAO) in vitro. Vse spojine z delovanjem na ChE so izkazale dobro selektivnost za zaviranje BChE v primerjavi z AChE. Najučinkovitejši zaviralci BChE iz serije [45 (IC50 = 22,24 nM), 46 (IC50 = 34,43 nM), 47 (IC50 = 27,16 nM) in 48 (IC50 = 21,02 nM)] so ta encim zavirale časovno odvisno, kar nakazuje na kovalentni mehanizem delovanja. Za spojino 45 smo kovalentni mehanizem zaviranja BChE potrdili z vrednotenjem encimske kinetike. Kovalentni mehanizem zaviranja najučinkovitejšega zaviralca MAO-B, spojine 36 (IC50 = 0,36 μM), je bil zaradi njene N-propargilne aminske skupine pričakovan. Med spojinami, ki zavirajo oba tarčna encima hkrati, je najbolj obetavna spojina 38 [IC50(BChE) = 34,69 μM; IC50(MAO-B) = 1,53 μM)]. S pričujočo magistrsko nalogo smo potrdili, da so N-alkilpirolidin karbamati zelo zanimivi novi zaviralci BChE oziroma MAO-B v nanomolarnem območju z velikim potencialom za razvoj v učinkovitejše in varnejše učinkovine za lajšanje simptomov in zdravljenje AB.

• Language: Slovenian
• Keywords: Alzheimerjeva bolezen, N-alkilpirolidin karbamati, butirilholin esteraza, monoamin oksidaza B, dvojni zaviralci butirilholin esteraze in monoamin oksidaze B
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2023
• PID: 20.500.12556/RUL-147028
• Publication date in RUL: 21.06.2023

Secondary language

• Language: English
• Title: Design, synthesis and evaluation of N-alkylpyrrolidine carbamates as inhibitors of cholinesterases and monoamine oxidases

Abstract

The selection of approved drugs for the (symptomatic) treatment of Alzheimer’s disease and their effectiveness are relatively limited, so the need for developing new agents for the therapy of this neurodegenerative disease is of great significance. Molecules acting on more than one target involved in the complex pathophysiology of Alzheimer’s disease are of great interest in this area of research. Two of the targets of the potential new active substances for the (symptomatic) treatment of Alzheimer’s disease are the enzymes butyrylcholinesterase (BChE) and monoamine oxidase B (MAO-B) – expression of both is increased in the brains of Alzheimer’s patients. Inhibition of BChE slows the breakdown of the neurotransmitter acetylcholine (ACh) and relieves the cognitive symptoms of Alzheimer’s disease without the cholinergic side effects typical of acetylcholine esterase (AChE) inhibitors. Inhibition of MAO-B reduces the oxidative stress, which fuels neurodegenerative processes. 30 new N-alkylpyrrolidine carbamates were prepared and their inhibitory activity on BChE and MAO-B was evaluated with enzymatic tests in vitro. All the compounds affecting the cholinesterases showed good selectivity towards BChE over AChE. The most effective BChE inhibitors of the series [45 (IC50 = 22,24 nM), 46 (IC50 = 34,43 nM), 47 (IC50 = 27,16 nM) and 48 (IC50 = 21,02 nM)] inhibited this enzyme in a time dependent manner which suggests the covalent mode of action. For compound 45, this was confirmed with enzyme kinetic measurements. Covalent binding of the most potent MAO-B inhibitor, compound 36 (IC50 = 0,36 μM), was expected based on the presence of the N-propargil amino group. Among the compounds that showed inhibitory activity against both target enzymes, compound 38 [IC50(BChE) = 34,69 μM; IC50(MAO-B) = 1,53 μM)] was the most promising. With this master thesis, we have demonstrated that N-alkylpyrrolidine carbamates are very interesting new BChE and MAO-B inhibitors in the nanomolar range with great potential to be developed into safer and more effective agents for alleviating the symptoms and treatment of Alzheimer’s disease.

• Keywords: Alzheimer’s disease, N-alkylpyrrolidine carbamates, butyrylcholinesterase, monoamine oxidase B, dual inhibitors of butyrylcholinesterase and monoamine oxidase B