Borisova Boryana, Vladimirova Stanislava, Nocheva Hristina, Laronze-Cochard Marie, Gérard Stéphane, Petrin Stoyko, Danalev Dancho
Biotechnology Department, University of Chemical Technology and Metallurgy, 8 Kliment Ohridski Blvd, 1756 Sofia, Bulgaria.
Organic Synthesis Department, University of Chemical Technology and Metallurgy, 8 Kliment Ohridski Blvd, 1756 Sofia, Bulgaria.
Biomedicines. 2023 Dec 9;11(12):3265. doi: 10.3390/biomedicines11123265.
Bioconjugates are promising alternatives for the multiple targeting of any disease. Pyrrole heterocycle is well known with many activities and is a building block of a lot of medical drugs. On the other hand, peptides are short molecules with many advantages such as small size, ability to penetrate the cell membrane and bond-specific receptors, vectorizing potential, etc. Thus, hybrid molecules between peptide and pyrrole moiety could be a promising alternative as an anti-pain tool.
New bioconjugates with a general formula Pyrrole (α-/β-acid)-FELL-OH (NH) were synthesized using Fmoc/OtBu peptide synthesis on solid support. HPLC was used to monitor the purity of newly synthesized bioconjugates. Their structures were proven by electrospray ionization mass spectrometry. The Paw Pressure test (Randall-Selitto test) was used to examinate the analgesic activity. Hydrolytic stability of targeted structures was monitored in three model systems with pH 2.0, 7.4 and 9.0, including specific enzymes by means of the HPLC-UV method.
The obtained results reveal that all newly synthesized bioconjugates have analgesic activity according to the used test but free pyrrole acids have the best analgesic activity.
Although free pyrrole acids showed the best analgesic activity, they are the most unstable for hydrolysis. Combination with peptide structure leads to the hydrolytic stabilization of the bioconjugates, albeit with slightly reduced activity.
生物共轭物是针对任何疾病进行多重靶向治疗的有前景的替代物。吡咯杂环具有多种活性，是许多药物的组成部分。另一方面，肽是短分子，具有许多优点，如尺寸小、能够穿透细胞膜并与特异性受体结合、具有载体化潜力等。因此，肽与吡咯部分之间的杂化分子可能是一种有前景的抗疼痛工具。
采用Fmoc/OtBu固相肽合成法合成了通式为吡咯（α-/β-酸）-FELL-OH（NH）的新型生物共轭物。用高效液相色谱法监测新合成生物共轭物的纯度。通过电喷雾电离质谱法证实其结构。采用爪压试验（兰德尔-塞利托试验）检测镇痛活性。通过HPLC-UV法在pH值为2.0、7.4和9.0的三种模型体系中监测靶向结构的水解稳定性，包括特定酶。
所得结果表明，根据所采用的试验，所有新合成的生物共轭物均具有镇痛活性，但游离吡咯酸具有最佳的镇痛活性。
尽管游离吡咯酸显示出最佳的镇痛活性，但它们在水解方面最不稳定。与肽结构结合可导致生物共轭物的水解稳定性增强，尽管活性略有降低。
