Di-O-lauroyl-decitabine-lipid nanocapsules: toward extending decitabine activity

Figures & data

Figure 1 Decitabine (C12)₂ synthesis.

Abbreviations: DCC, dicyclohexylcarbodiimide; DMAP, 4-(dimethylamino) pyridine.

Figure 2 Preparation of lipid nanocapsules loaded with decitabine (C12)₂ by phase inversion temperature.

Abbreviation: LNCs, lipid-core nanocapsules.

Table 1 Gradient elution in the LC-MS/MS method

Time (minutes)	Phase A (%)	Phase B (%)	Flow (mL/minutes)
0.00	20	80	0.200
6.00	28	72	0.200
6.10	28	72	0.300
7.00	20	80	0.300
12.00	20	80	0.300

Note: Mobile phase A consisted of a mixture of 10 mM ammonium acetate and 0.1% formic acid (v/v) and mobile phase B consisted of acetonitrile and 0.1% formic acid (v/v).

Abbreviation: LC-MS/MS, liquid chromatography method using tandem mass spectrometry.

Table 2 Physiochemical characterizations of blank and loaded LNC formulations (n=3)

LNC formulations	Size (nm)	PDI	Encapsulation efficiency (%)	Drug loading (mg/mL)
Blank LNCs	27.54±0.19	0.05±0.01	–	–
Decitabine (C12)2-loaded LNCs	27.45±0.05	0.05±0.01	100±0.7	5.8±0.5
Matured decitabine (C12)2-loaded LNCsa	28.32±0.38	0.07±0.01	103±0.09	4.0±0.4

Note:

a Formulations were stored at 4°C for 15 days.

Abbreviations: LNC, lipid-core nanocapsule; PDI, polydispersity index.

Figure 3 Physiochemical behavior of decitabine (C12)₂ PBS-loaded LNCs in PBS at 37°C for 48 hours (n=3). Drug loading and residual decitabine (C12)₂ concentration remained unchanged for the first 12 hours and decreased thereafter (A), whereas the size and PDI remained unchanged for 48 hours (B).

Abbreviations: LNC, lipid-core nanocapsule; PDI, polydispersity index.

Figure 4 Decitabine (C12)₂ stability in human plasma. Decitabine (C12)₂-loaded LNCs were incubated in human plasma at 37°C for 24 hours. The decitabine-(C12)₂ concentration at the initial timepoint (T0) was considered to be 100% (n=3).

Abbreviation: LNCs, lipid-core nanocapsules.

Figure 5 Cell proliferation study of HEL following exposure to various concentrations of blank LNCs (indicated below each bar graph), decitabine solution, decitabine (C12)₂-loaded LNCs, or decitabine (C12)₂ solution. Cells cultured with medium alone were considered to correspond to 100% viability (n=3 plates, quadruplicate).

Note: *P<0.05 Mann–Whitney test.

Abbreviations: HEL, human erythroleukemia cell line; LNCs, lipid-core nanocapsules.

Figure 6 Cell-cycle analysis of HEL cells following exposure to RPMI (A), blank LNCs (B), decitabine solution (C), or decitabine (C12)₂-loaded LNCs (D) also as expressed as a percentage of cells blocked in G2/M phase (E) (n=3 plates, in triplicate).

Note: *P<0.05 Mann–Whitney test vs cells treated with RPMI.

Abbreviations: HEL, human erythroleukemia cell line; LNCs, lipid-core nanocapsules; RPMI, Roswell Park Memorial Institute medium 1640.

Table 3 Main pharmacokinetic parameters of decitabine and decitabine (C12)₂ following IV administration of 5 mg/kg decitabine or 12.5 mg/kg decitabine (C12)₂

Parameters	Decitabine	Decitabine (C12)2	Decitabine (after decitabine (C12)2-loaded LNC injection)
Cmax(µM)	36±8	307±80	6±1
AUC (µM×h)	82±15	246±74	31±3
MRT (h)	3.4±0.4	1.5±0.9	4.5±0.3
Tmax(min)	2±0	2±0	84±33

Note: Data were obtained using an intravascular non-compartmental analysis following IV administration of decitabine (C12)₂-loaded LNCs, except for decitabine parameters for which an extravascular non-compartmental analysis was performed.

Abbreviations: AUC, area under the plasma concentration-time curve; IV, intravenous; LNCs, lipid-core nanocapsules; MRT, mean residence time.

Figure 7 Evolutions of plasma concentrations of active pharmaceutical ingredients over time following IV bolus administration of a decitabine solution or a decitabine (C12)_2-loaded LNCs solution.

Note: Results are presented as mean±SEM (n=5 for each group).

Abbreviations: API, active pharmaceutical ingredient; DAC, decitabine; IV, intravenous; LNCs, lipid-core nanocapsules; SEM, standard error of the mean.