Dequalinium-derived nanoconstructs: A promising vehicle for mitochondrial targeting

The power house of the cell; mitochondrion, is a vital organelle for drug targeting in the treatment of many diseases owing to its fundamental duties and function related to cell proliferation and death. The mitochondrial membrane comprises bilayer artifact and pose extremely negative potential which create hurdle for therapeutic molecules in reaching mitochondria. To accomplish mitochondrial targeting, the scientific community has explored diverse pharmaceutical formulations like liposomes, polymeric nanoparticles (NPs), and inorganic NPs. However, the game changing technology was modification of these carriers by mitochondriotropic moiety, dequalinium chloride (DQA) or delivering the chemotherapeutics by DQAsomes. The DQA represents a distinctive mitochondriotropic delocalized cation that display their selectivity towards accumulation in mitochondria of carcinoma cell. Attributed to this characteristics, DQAsomes have been formulated using DQA and explored for successful mitochondrial targeting of bioactives. In this review, we have discussed the effectiveness of DQA nanocarriers which efficiently and selectively transmit the cytotoxic drug to the tumor cell. The DQA based nanoformulations have evidently displayed augmented pharmacological and therapeutic outcome than their counterparts both in vitro and in vivo. Thus, DQAsomes symbolizes an ideal carrier with excellent potential as mitochondial targeting agent.

DQAsomes as the Prototype of Mitochondria-Targeted Pharmaceutical Nanocarriers : An Update

DQAsomes (dequalinium-based liposome-like vesicles) are the prototype for all mitochondria-targeted vesicular pharmaceutical nanocarrier systems. First described in 1998 in a paper which has been cited as of May 2020 over 150 times, DQAsomes have been successfully explored for the delivery of DNA and low-molecular weight molecules to mitochondria within living mammalian cells. Moreover, they also appear to have triggered the design and development of a large variety of similar mitochondria-targeted nanocarriers . Potential areas of application of DQAsomes and of related mitochondria-targeted pharmaceutical nanocarriers involve mitochondrial gene therapy , antioxidant and updated therapy as well as apoptosis-based anticancer chemotherapy. Here, detailed protocols for the preparation, characterization, and application of DQAsomes are given and most recent developments involving the design and use of DQAsome-related particles are highlighted and discussed.

Mitochondria-targeted delivery of doxorubicin to enhance antitumor activity with HER-2 peptide-mediated multifunctional pH-sensitive DQAsomes

Introduction

Multidrug resistance (MDR) of breast cancer is the major challenge to successful chemotherapy while mitochondria-targeting therapy was a promising strategy to overcome MDR.

Materials and methods

In this study, HER-2 peptide-PEG₂₀₀₀-Schiff base-cholesterol (HPSC) derivate was synthesized successfully and incorporated it on the surface of the doxorubicin (DOX)-loaded dequalinium (DQA) chloride vesicle (HPS-DQAsomes) to treat drug-resistant breast cancer. Evaluations were performed using human breast cancer cell and DOX-resistant breast cancer cell lines (MCF-7 and MCF-7/ADR).

Results

The particle size of HPS-DQAsomes was ~110 nm with spherical shape. In vitro cytotoxicity assay indicated that HPS-DQAsomes could increase the cytotoxicity against MCF-7/ADR cell line. Cellular uptake and mitochondria-targeting assay demonstrated that HPS-DQAsomes could target delivering therapeutical agent to mitochondria and inducing mitochondria-driven apoptosis process. In vivo antitumor assay suggested that HPS-DQAsomes could reach favorable antitumor activity due to both tumor targetability and sub-organelles’ targetability. Histological assay also indicated that HPS-DQAsomes showed a strong apoptosis-inducing effect. No obvious systematic toxicity of HPS-DQAsomes could be observed.

Conclusion

In summary, multifunctional HPS-DQAsomes provide a novel and versatile approach for overcoming MDR via mitochondrial pathway in cancer treatment.

Nanopreparations for mitochondria targeting drug delivery system: Current strategies and future prospective

Mitochondria are a novel and promising therapeutic target for diagnosis, treatment and prevention of a lot of human diseases such as cancer, metabolic diseases and neurodegenerative disease. Owing to the mitochondrial special bilayer structure and highly negative potential nature, therapeutic molecules have multiple difficulties in reaching mitochondria. To overcome multiple barriers for targeting mitochondria, the researchers developed various pharmaceutical preparations such as liposomes, polymeric nanoparticles and inorganic nanoparticles modified by mitochondriotropic moieties like dequalinium (DQA), triphenylphosphonium (TPP), mitochondrial penetrating peptides (MPPs) and mitochondrial protein import machinery that allow specific targeting. The targeted formulations exhibited enhanced pharmacological effect and better therapeutic effect than their untargeted counterpart both in vitro and in vivo. Nanocarriers may be used for bio-therapeutic delivery into specific mitochondria that possess a great potential treatment of mitochondria related diseases.