| In vitro | Method: Hydrogenated soya phosphatidylcholines (a hydrogenated soybean phospholipid mixture) was used to prepare cholesterol–phospholipid liposomal vesicles encapsulating natamycin by two techniques. For the proliposome method, 0.9 g Hydrogenated soya phosphatidylcholines, cholesterol (0.125 g), and natamycin (30 mg) were mixed with 1.5 mL ethanol, stirred at 45 °C, 400 rpm for ~30 min to evaporate solvent, then hydrated with 30 mL PBS (pH ~5.5) in portions and stirred 1 h at 800 rpm at room temperature. For the thin film method, 1 g Hydrogenated soya phosphatidylcholines, natamycin (30 mg), and cholesterol (0.150 mg) were dissolved in 5 mL chloroform:methanol (2:1), solvents evaporated under 100 mm Hg at 60 °C, 600 rpm for ~1 h to form a film, then hydrated with 30 mL PBS (pH ~5.5) for 1 h at 60 °C. Plain (drug-free) liposomes were prepared as controls. HaCaT human keratinocytes were exposed to these formulations, including free natamycin, and viability was quantified by MTT assay; the highest tested concentration corresponded to 10% liposomal sample, i.e., 100 µg/mL natamycin in loaded vesicles or solution. A non-treated negative control (100 ± 7.68% viability) was included. Statistical significance at 10% was assessed (**** p<0.0001). Result: At 10% formulation (100 µg/mL natamycin), all liposomal formulations prepared with Hydrogenated soya phosphatidylcholines or Lipoid S100, with or without natamycin, and free natamycin reduced HaCaT viability, indicating a concentration-dependent inhibitory effect; all values remained above 80% viability. Free natamycin showed slightly higher cell viability than encapsulated forms at 100 µg/mL. Differences across formulations were significant at the 10% level (**** p<0.0001). [2] Method: MCF-7 breast adenocarcinoma cells were treated with paclitaxel-loaded liposomes formulated from Hydrogenated soya phosphatidylcholines and cholesterol (HSPC:cholesterol:PCL = 7:2:0.1) prepared by thin-film hydration; cytotoxicity was assessed over 24 h and 48 h, and compared with free paclitaxel. Result: Liposomal paclitaxel showed time-dependent cytotoxicity with IC50 decreasing from 0.525 µg/mL at 24 h to 0.09 µg/mL at 48 h, which was 54% superior to free paclitaxel (IC50 = 0.139 µg/mL). [4] Method: Mechanistic assays in MCF-7 cells treated with paclitaxel-loaded Hydrogenated soya phosphatidylcholines liposomes evaluated cell-cycle distribution, caspase activation, cellular uptake, and anti-metastatic effects (migration and invasion). Result: Compared with control, treatment induced 2.96-fold G2/M accumulation (63.23% vs. 21.38%, p<0.001), mitochondrial apoptosis with 2.8-fold caspase-3 and 3.1-fold caspase-9 activation, 4.2-fold enhanced cellular uptake, and anti-metastatic activity with 62% migration and 68% invasion inhibition. [4] Method: High-molecular-weight hyaluronic acid was mixed with gel-phase hydrogenated soy PC (HSPC) to form HA-HSPC complexes, and surface force balance measurements were performed to quantify boundary lubrication friction under high pressure; additional assays assessed lipid assembly, phase transition temperature, and bilayer spreading upon interfacial contact, and examined disruption of the HA network and shear-thinning properties. Result: HA binding to HSPC altered lipid assembly, increased phase transition temperatures, and promoted bilayer spreading upon interfacial contact; lipids disrupted the HA network and enhanced shear-thinning; surface force balance measurements showed ultralow friction μ ≈ 10^-5–10^-3 that remained robust under high pressure for the HA-HSPC complex. [5] |
| In vivo | Method: Mice were intravenously injected with oxymatrine HSPC liposomes (50 mg/kg). Plasma samples were collected at various time points post-administration, extracted by solid-phase extraction, and analyzed by high-performance liquid chromatography for concentrations of oxymatrine and its metabolite matrine. Pharmacokinetic parameters were calculated using a non-compartmental model. Result: The half-life of oxymatrine in the HSPC liposome group was 17.10 h, which was 6.6 times longer than that of the oxymatrine solution group (2.58 h). The AUC(0-∞) was 724.41 mg·h/mL, 11.5 times higher than the solution group (63.11 mg·h/mL). The MRT(0-8) of matrine reached 67.50 h, 14.3 times higher than the solution group (4.71 h) [6]. Method: Mice were intravenously injected with oxymatrine HSPC liposomes (50 mg/kg) and sacrificed at 0.083, 1.0, and 8.0 h post-administration. Liver, spleen, heart, and kidney tissues were collected, homogenized, extracted by solid-phase extraction, and analyzed by high-performance liquid chromatography for oxymatrine and matrine distribution. The AUC(0-8) of total alkaloids in the liver was calculated. Result: The AUC(0-8) of total alkaloids in the liver for the HSPC liposome group was 553.55 mg·h/mL, which was 2.37 times that of the oxymatrine solution group (234.03 mg·h/mL) and 4.18 times that of the SPC liposome group (132.46 mg·h/mL), indicating that HSPC liposomes significantly enhanced hepatic targeting distribution and accumulation of the drug [6]. Method: CCl₄-induced acute liver injury mice were treated with oxymatrine HSPC liposomes by either oral gavage or tail vein injection (50 mg/kg). Liver tissues were collected at various time points for H&E staining histopathological examination, and serum ALT and AST activities were measured to evaluate the therapeutic effect of HSPC liposomes on liver injury. Result: The HSPC liposome treatment group showed significantly improved focal necrosis and ballooning degeneration in the liver, with gradual restoration of damaged liver tissue. Serum ALT and AST levels at 36 h (the most severe phase of liver injury) were significantly lower than those in the oxymatrine solution group (P<0.01) [6]. |