TPP-alantolactone conjugates and their nanotherapeutic forms for antitumor application

Area of Science:

• Nanotechnology and Drug Delivery
• Mitochondrial-Targeted Cancer Therapy
• Antimicrobial Agents

Background:

• Mitochondrial-targeted drug delivery presents a challenge for novel cancer therapies.
• Triarylphosphonium (TPP) groups enhance cell and mitochondrial membrane penetration due to positive charge and hydrophobicity.
• Combining nanotechnology with mitochondrial strategies is crucial for effective cancer treatment.

Purpose of the Study:

• To synthesize quaternary γ-oxoalkylphosphonium salts (TPP-alantolactone, TPP-AL) for targeted delivery into mitochondria.
• To develop and characterize novel mitochondria-targeted lipid nanosystems (liposomes and solid lipid nanoparticles, SLN) modified with TPP-AL.
• To evaluate the in vitro cytotoxicity, cellular uptake, mitochondrial effects, and antibacterial activity of TPP-AL and its nanosystems.

Main Methods:

• Synthesis of TPP-alantolactone (TPP-AL) under mild conditions with high yields.
• Preparation and characterization of TPP-AL modified liposomes and solid lipid nanoparticles (TPP-AL-SLN).
• In vitro cytotoxicity assays (IC50), cellular uptake studies using confocal microscopy, mitochondrial membrane potential assessment, ROS production, caspase-9 expression analysis, and cell cycle analysis.
• Antibacterial activity testing, including minimum bactericidal concentration (MBC) determination.

Main Results:

• TPP-AL demonstrated high in vitro cytotoxicity against human duodenal adenocarcinoma (HuTu 80) cells (IC50 = 0.4 µM) with high selectivity (17.5).
• TPP-alantolactone-SLN (TPP-AL-SLN) exhibited significantly enhanced cytotoxicity (up to 520-fold increase) against M-HeLa cancer cell lines.
• TPP-AL induced mitochondrial membrane depolarization, increased ROS production, and caspase-9 overexpression, indicating apoptosis induction via intrinsic mitochondrial pathways.
• TPP-AL showed significant bactericidal activity against Gram-positive bacteria, including MRSA (MBC = 7.8 µM), comparable to norfloxacin.

Conclusions:

• Mitochondria-targeted TPP-AL modified nanosystems (liposomes and SLN) are effective drug delivery platforms for cancer therapy.
• TPP-AL triggers apoptosis through intrinsic mitochondrial pathways and exhibits dual-action as both an antitumor and antibacterial agent.
• These TPP-derived sesquiterpene lactones-decorated nanosystems hold significant potential for targeted cancer treatment and combating bacterial infections.