Povzetek
In addition to antibacterial and antitumor effects, synthetic ruthenium complexes have been reported to inhibit several medicinally important enzymes, including acetylcholinesterase (AChE). They may also interact with muscle-type nicotinic acetylcholine receptors (nAChRs) and thus affect the neuromuscular transmission and muscle function. In the present study, the effects of the organometallic ruthenium complex of 5-nitro-1,10- phenanthroline (nitrophen) were evaluated on these systems. The organoruthenium-nitrophen complex [(η$^6$-pcymene)Ru(nitrophen)Cl]Cl; C$_{22}$H$_{21}$Cl$_2$N$_3$O$_2$Ru (C1-Cl) was synthesized, structurally characterized and evaluated in vitro for its inhibitory activity against electric eel acetylcholinesterase (eeAChE), human recombinant acetylcholinesterase (hrAChE), horse serum butyrylcholinesterase (hsBChE) and horse liver glutathione-Stransferase. The physiological effects of C1-Cl were then studied on isolated mouse phrenic nerve-hemidiaphragm muscle preparations, by means of single twitch measurements and electrophysiological recordings. The compound C1-Cl acted as a competitive inhibitor of eeAChE, hrAChE and hsBChE with concentrations producing 50 % inhibition (IC$_{50}$) of enzyme activity ranging from 16 to 26 μM. Moreover, C1-Cl inhibited the nerve-evoked isometric muscle contraction (IC$_{50}$ = 19.44 μM), without affecting the directly-evoked muscle single twitch up to 40 μM. The blocking effect of C1-Cl was rapid and almost completely reversed by neostigmine, a reversible cholinesterase inhibitor. The endplate potentials were also inhibited by C1-Cl in a concentration-dependent manner (IC$_{50}$ = 7.6 μM) without any significant change in the resting membrane potential of muscle fibers up to 40 μM. Finally, C1-Cl (5–40 μM) decreased (i) the amplitude of miniature endplate potentials until a complete block by concentrations higher than 25 μM and (ii) their frequency at 10 μM or higher concentrations. The compound C1-Cl reversibly blocked the neuromuscular transmission in vitro by a non-depolarizing mechanism and mainly through an action on postsynaptic nAChRs. The compound C1-Cl may be therefore interesting for further preclinical testing as a new competitive neuromuscular blocking, and thus myorelaxant, drug.
Ključne besede
organoruthenium nitrophenanthroline complex;acetylcholinesterase;butyrylcholinesterase;glutathione S-transferase;mouse neuromuscular system;ruthenium;muscle relaxation;physiology;glutathione transferase;
Podatki
Jezik: |
Angleški jezik |
Leto izida: |
2020 |
Tipologija: |
1.01 - Izvirni znanstveni članek |
Organizacija: |
UL VF - Veterinarska fakulteta |
UDK: |
577.15:612.741 |
COBISS: |
13704451
|
ISSN: |
1950-6007 |
Št. ogledov: |
438 |
Št. prenosov: |
84 |
Ocena: |
0 (0 glasov) |
Metapodatki: |
|
Ostali podatki
Sekundarne ključne besede: |
Ruthenium;Acetylcholinesterase;Muscle relaxation;Physiology;Glutathione Transferase; |
Vrsta dela (COBISS): |
Članek v reviji |
Strani: |
str. 1-11 |
Letnik: |
ǂVol. ǂ127 |
Zvezek: |
ǂart. no. ǂ110161 |
Čas izdaje: |
2020 |
DOI: |
10.1016/j.biopha.2020.110161 |
ID: |
11954088 |