Evaluation of herb-drug interaction of ambrisentan with shikonin based on UPLC-MS/MS

Figures & data

Table 1. MS parameters for ambrisentan, (S)-4-hydroxymethyl ambrisentan and midazolam.

Compound name	Precursor ion (m/z)	Product ion (m/z)	Collision energy (V)	Cone voltage (V)
Ambrisentan	379.24	347.28	5	10
(S)-4-Hydroxymethyl ambrisentan	395.11	363.17	5	30
Midazolam	326.20	291.0	30	60

Figure 1. UPLC–MS/MS chromatograms of ambrisentan, its metabolite (S)-4-hydroxymethyl ambrisentan and IS. (A) A blank serum sample; (B) a blank plasma sample spiked with ambrisentan, (S)-4-hydroxymethyl ambrisentan and IS; (C) a rat plasma sample.

Table 2. Precision, accuracy, matrix effect (ME) and recovery for analytes of QC sample in rat plasma (n = 6).

	Concentration	Intra-day			Inter-day
Analytes	ng/mL	Mean ± SD	RSD (%)	RE (%)	Mean ± SD	RSD (%)	RE (%)	Recovery (%)	ME (%)
	4	4.37 ± 0.19	4.25	9.33	4.33 ± 0.11	2.52	8.22	104.16	118.49
4-(S)-Hydroxymethyl ambrisentan	40	41.35 ± 1.44	3.49	3.37	41.63 ± 0.49	1.19	4.08	105.89	108.56
	400	420.91 ± 15.12	3.59	5.23	426.67 ± 6.18	1.45	6.67	109.62	109.61
	400	420.65 ± 33.90	8.06	5.16	421.77 ± 18.59	4.41	5.44	93.66	102.34
Ambrisentan	4000	3968.10 ± 277.363	6.99	−0.80	4107.74 ± 128.31	3.12	2.69	91.51	95.82
	8000	8209.13 ± 151.21	1.84	2.61	7822.28 ± 337.01	4.31	−2.22	105.57	116.47

Figure 2. Mean ± SD concentration–time curve of ambrisentan (A) and (S)-4-hydroxymethyl ambrisentan (B) in two groups (n = 6 each group).

Table 3. The main pharmacokinetic parameters of ambrisentan in rat plasma in two groups (n = 6).

Parameters	Group A	Group B
AUC(0–t) (μg/L·h)	41,308.92 ± 19,275.09	53,368.89 ± 7,683.32*
AUC(0–∞) (μg/L·h)	44,893.16 ± 22,304.94	53,861.05 ± 7,773.54*
t1/2z (h)	0.92 ± 0.42	0.55 ± 0.11
Tmax (h)	0.60 ± 0.55	0.22 ± 0.08
Vz/F (L/kg)	0.09 ± 0.06	0.04 ± 0.01
CLz/F (L/h/kg)	0.07 ± 0.03	0.05 ± 0.01
Cmax (μg/L)	31,474.53 ± 18,255.05	57,182.51 ± 14,900.22*

Group A: control group; Group B: a single dose of 20 mg/kg shikonin. *p < 0.05.

Table 4. The main pharmacokinetic parameters of (S)-4-hydroxymethyl ambrisentan in rat plasma in two groups (n = 6).

Parameters	Group A	Group B
AUC(0–t) (μg/L·h)	1,383.75 ± 329.16	961.42 ± 372.20*
AUC(0–∞) (μg/L·h)	1,417.66 ± 343.58	994.23 ± 384.29*
t1/2z (h)	1.59 ± 0.26	1.25 ± 0.65
Tmax (h)	0.55 ± 0.21	0.65 ± 0.22
Vz/F (L/kg)	4.20 ± 1.05	4.91 ± 2.51
CLz/F (L/h/kg)	1.85 ± 0.46	2.86 ± 1.17
Cmax (μg/L)	883.37 ± 221.66	482.91 ± 141.83*

Group A: control group; Group B: a single dose of 20 mg/kg shikonin. *p < 0.05.

Figure 3. Various concentrations of shikonin for half-maximal inhibitory concentration (IC₅₀) in the activity of (A) rat liver microsomes and (B) human liver microsomes. Values are mean ± SD, n = 3.