Soleymani-Goloujeh Mehdi, Nokhodchi Ali, Niazi Mehri, Najafi-Hajivar Saeedeh, Shahbazi-Mojarrad Javid, Zarghami Nosratollah, Zakeri-Milani Parvin, Mohammadi Ali, Karimi Mohammad, Valizadeh Hadi
a Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences , Tabriz University of Medical Sciences , Tabriz , Iran.
b Department of Stem Cells and Developmental Biology at Cell Science Research Center , Royan Institute for Stem Cell Biology and Technology, ACECR , Tehran , Iran.
Artif Cells Nanomed Biotechnol. 2018;46(sup1):91-103. doi: 10.1080/21691401.2017.1414823. Epub 2017 Dec 19.
To assess the effect of "N-Acetylation and C-Amidation" on the cellular uptake, cytotoxicity and performance of amphiphilic cell penetrating peptides (CPP) loaded with methotrexate (MTX).
Several CPPs were synthesized by solid phase peptide synthesis method. Some of these sequences were modified with pyroglutamic acid at N-terminus and benzylamine or memantine at C-terminus. The resultant nanomaterials were prepared due to the physical linkage between CPPs and MTX. The internalization and cytotoxicity of both CPP-MTX bioconjugates and unmodified CPPs against MCF-7 human breast adenocarcinoma cells was evaluated.
N-l and C-terminal modification did not alter the toxicity of CPPs. Physical linkage of CPPs with MTX resulted in a lower drug loading efficiency in comparison with chemically conjugated CPP-MTX bio-conjugates. Both nano-complexes increase the toxic effect of MTX on MCF-7 cells. Furthermore, N- and C-terminal modification may cause a tangible reduction in cellular uptake of CPPs.
In conclusion, it was shown that cytotoxicity of modified peptides which were physically linked with MTX, considerably higher than both physically loaded unmodified peptides and chemically conjugated peptides with MTX. Also, cell internalization was reduced after peptide end-protection. These findings confirmed the effectiveness of N- and C-terminal modifications on cell viability and CPPs internalization.
评估“N-乙酰化和C-酰胺化”对负载甲氨蝶呤（MTX）的两亲性细胞穿透肽（CPP）的细胞摄取、细胞毒性及性能的影响。
采用固相肽合成法合成了几种CPP。其中一些序列在N端用焦谷氨酸修饰，在C端用苄胺或美金刚修饰。由于CPP与MTX之间的物理连接，制备了所得纳米材料。评估了CPP-MTX生物共轭物和未修饰的CPP对MCF-7人乳腺腺癌细胞的内化作用和细胞毒性。
N端和C端修饰未改变CPP的毒性。与化学共轭的CPP-MTX生物共轭物相比，CPP与MTX的物理连接导致较低的载药效率。两种纳米复合物均增加了MTX对MCF-7细胞的毒性作用。此外，N端和C端修饰可能会导致CPP细胞摄取的明显降低。
总之，结果表明，与MTX物理连接的修饰肽的细胞毒性显著高于与MTX物理负载的未修饰肽和化学共轭肽。此外，肽末端保护后细胞内化减少。这些发现证实了N端和C端修饰对细胞活力和CPP内化的有效性。
