Preparation, Characterization, and Biodistribution of Glutathione PEGylated Nanoliposomal Doxorubicin for Brain Drug Delivery with A Post-insertion Approach

Abstract

Brain cancer treatments have been largely unsuccessful due to the blood-brain barrier. Several publications support the presence of glutathione (GSH) receptors on the surface of the BBB and consequently the products such as the 2B3-101, which is almost 5% pre-inserted GSH PEGylated liposomal doxorubicin, is under process in clinical studies. Here we conducted the PEGylated nanoliposomal doxorubicin particles that are covalently attached to the glutathione using the post-insertion technique. The post-insertion methodology is noticeably simpler, faster, and more cost-effective compared to the pre-insertion method which makes it desirable for large-scale pharmaceutical manufacturing. The 25, 50, 100, 200, and 400 ligands of the DSPE PEG(2000) Maleimide-GSH complexes were incorporated into the available Caelyx. According to the animal studies such as biodistribution, fluorescent microscopy, and pharmacokinetic studies, the 200L and 400L treatment arms were the most promising formulations compared to the Caelyx. They proved that post-inserted nanocarriers with 40 times lower levels of GSH micelles compared to the 2B3-101 have significantly increased the penetrance through the blood-brain barrier. Other tissue analysis showed that the doxorubicin will likely accumulate in the liver, spleen, heart, and lung in comparison with the Caelyx due to the expressed GSH receptors on tissues as an endogenous antioxidant. In conclusion, as was expected, the post-insertion technique was found a successful approach with more pharmaceutical aspects for large-scale production. Moreover, it is highly recommended further investigations to determine the efficacy of 5% post-inserted GSH targeted nanoliposomes versus the 2B3-101 as a similar formulation with a different preparation method.

The comparison of biodistribution of glutathione PEGylated nanoliposomal doxorubicin formulations prepared by pre‐insertion and post‐insertion methods for brain delivery in normal mice

“…The distribution of the medications in the blood showed that their concentration decreased after 2 days, possibly due to their accumulation in other tissues, particularly the liver and spleen. This result is consistent with prior research, which found that drug distribution into the blood was dramatically reduced after 2‐ or 3‐days post‐injection [ 24 , 28 , 57 ]. The higher distribution of pre‐ and post‐inserted formulations in the liver and spleen seemed to be due to the presence of the reticuloendothelial system (RES), which was able to rapidly take up the formulations and resulted entrapment in the mentioned organs.…”

“…The results showed that this method is simple, cost-effective and reproducible when generating actively targeted liposomal DOX [25][26][27]. Similarly, in our previous work, using the post-insertion method, we demonstrated that GSH-targeted liposomes penetrated the BBB efficiently [28].…”

“…For future clinical development, the post‐insertion approach appears to be quite promising [ 29 , 30 , 31 ]. In the previous study conducted by our team, using 200 and 400 GSH ligands applied on the available Caelyx ® via the post‐insertion method could improve crossing through the BBB and brain biodistribution [ 28 ].…”

Preparation, characterization and wound‐healing effect of PEGylated nanoliposomes loaded with oleuropein

“…The mean size, charge and PDI of PEG-nanoliposomes loaded with oleu (PEG-oleu) were 129.35 nm, À9.55 mV and 0.1010, respectively. All size, charge and PDI results at time 0, 24, and 48 h and 1 week are within the optimum nanoliposome values(Mehrabian et al, 2022). In addition, one-way ANOVA was performed to investigate the impact of storage time at 4 C on nanoliposome characterization, as shown in Table4.…”