Combining mitochondrial antioxidant mitoquinone and mesenchymal stem cell therapy for amelioration of radiation-induced lung injury: Synergistic regenerative strategy

Table 1 Comparison of lung function indexes in different groups at different time points

Indicators	Time point	Model group (n = 20)	MitoQ group (n = 20)	MSCs group (n = 20)	Combination group (n = 20)	Group effect F(P)	Time effect F(P)	Interaction F(P)
Raw (cmH2O∙second/mL)	7 days	2.12 ± 0.16	1.95 ± 0.14	1.92 ± 0.13	1.84 ± 0.15	42.317 (< 0.001)	31.582 (< 0.001)	12.441 (0.003)
	14 days	2.31 ± 0.17	1.92 ± 0.13	1.88 ± 0.14	1.77 ± 0.13
	28 days	2.45 ± 0.18	1.89 ± 0.13	1.94 ± 0.14	1.72 ± 0.12
Crs (mL/cmH2O)	7 days	0.025 ± 0.003	0.028 ± 0.003	0.029 ± 0.004	0.030 ± 0.003	38.502 (< 0.001)	28.476 (< 0.001)	10.825 (0.004)
	14 days	0.023 ± 0.003	0.029 ± 0.003	0.029 ± 0.004	0.031 ± 0.003
	28 days	0.021 ± 0.003	0.028 ± 0.003	0.029 ± 0.004	0.031 ± 0.004

MitoQ: Mitoquinone; MSC: Mesenchymal stem cell.

Table 2 Comparison of oxidative stress indicators on day 28

Indicators	Model group (n = 20)	MitoQ group (n = 20)	MSCs group (n = 20)	Combination group (n = 20)	F value	P value
ROS (fluorescence intensity)	1.78 ± 0.14	1.24 ± 0.10	1.22 ± 0.09	1.18 ± 0.09	28.416	< 0.001
MDA (nmol/mg protein)	5.62 ± 0.41	3.98 ± 0.36	3.99 ± 0.35	3.71 ± 0.31	25.317	< 0.001
GSH (μmol/g protein)	18.32 ± 1.24	22.71 ± 1.15	23.05 ± 1.16	23.71 ± 1.15	26.145	< 0.001

MitoQ: Mitoquinone; MSC: Mesenchymal stem cell; ROS: Reactive oxygen species; MDA: Malondialdehyde; GSH: Glutathione.

Table 3 Comparison of mitochondrial function indexes on day 28

Indicators	Model group (n = 20)	MitoQ group (n = 20)	MSCs group (n = 20)	Combination group (n = 20)	F value	P value
JC-1 red-green ratio	0.52 ± 0.05	0.69 ± 0.06	0.71 ± 0.05	0.78 ± 0.06	32.148	< 0.001
ATP (nmol/mg protein)	3.12 ± 0.27	3.88 ± 0.29	3.95 ± 0.30	4.12 ± 0.31	28.672	< 0.001
Swelling/ridge fracture ratio (%)	36.8 ± 3.5	21.4 ± 2.7	19.8 ± 2.5	15.3 ± 2.2	30.506	< 0.001

MitoQ: Mitoquinone; MSC: Mesenchymal stem cell.

Table 4 Comparison of fibrosis and inflammation indicators on day 28

Indicators	Model group (n = 20)	MitoQ group (n = 20)	MSCs group (n = 20)	Combination group (n = 20)	F value	P value
Collagen deposition area (%)	28.4 ± 3.1	18.7 ± 2.4	17.9 ± 2.3	12.3 ± 2.1	29.417	< 0.001
α-SMA (gray value)	2.18 ± 0.21	1.38 ± 0.15	1.31 ± 0.14	1.12 ± 0.14	31.128	< 0.001
TGF-β1 (gray value)	2.35 ± 0.26	1.42 ± 0.16	1.39 ± 0.15	1.18 ± 0.15	30.504	< 0.001
Inflammation score (0-4 points)	2.8 ± 0.6	1.6 ± 0.4	1.5 ± 0.3	0.9 ± 0.3	27.916	< 0.001

MitoQ: Mitoquinone; MSC: Mesenchymal stem cell; α-SMA: Α-smooth muscle actin; TGF-β1: Transforming growth factor-β1.

Table 5 Logistics regression analysis results of factors associated with pulmonary fibrosis and mitochondrial dysfunction

Factor	β	SE	Wald χ2	P value	OR	95%CI
Constant term	-4.217	1.032	16.712	< 0.001	-	-
ROS	1.548	0.482	10.324	0.001	4.7	1.85-11.95
MDA	1.372	0.441	9.684	0.002	3.94	1.65-9.41
GSH	-1.215	0.387	9.839	0.002	0.3	0.13-0.66
α-SMA	1.486	0.459	10.469	0.001	4.42	1.75-11.17
TGF-β1	1.324	0.432	9.382	0.002	3.76	1.57-9.02
Inflammation score	0.987	0.381	6.706	0.01	2.68	1.26-5.72

Pulmonary fibrosis was defined as collagen deposition area ≥ 20% (1 ≥ 20% and 0 < 20%). Mitochondrial dysfunction was defined as JC-1 red-green ratio < 0.6 or ATP < 3.5 nmol/mg protein (1 = dysfunction and 0 = normal). Independent variables included reactive oxygen species (fluorescence intensity), malondialdehyde (nmol/mg protein), glutathione (μmol/g protein), α-smooth muscle actin and transforming growth factor-β1 (gray value), and inflammation score (0-4). OR: Odds ratio; CI: Confidence interval; ROS: Reactive oxygen species; MDA: Malondialdehyde; GSH: Glutathione; α-SMA: Α-smooth muscle actin; TGF-β1: Transforming growth factor-β1.