Pre-radiotherapy plasma carotenoids and markers of oxidative stress are associated with survival in head and neck squamous cell carcinoma patients: a prospective study

Table 2 Antioxidants in healthy controls and patients, both pre- and post radiotherapy

Antioxidants^a		Controls	Patients
			Pre-radiotherapy^b	Post-radiotherapy^c
Carotenoids (nmol/L)	Lutein	142.5	95.6^d	51.0^d
	Zeaxanthin	35.6	22.4^d	12.2^d
	β-cryptoxanthin	131.3	60.3^d	27.5^d
	α-carotene	107.6	61.3^d	56.7^e
	β-carotene	374.7	241.0^d	229.5
	Lycopene	533.3	243.9^d	124.6^d
	Total carotenoids	1325.1	703.1^d	474.5^d
Tocopherols (μmol/L)	δ-tocopherol	0.030	0.080^d	0.042^e
	β-tocopherol	0.419	0.466	0.362^d
	γ-tocopherol	1.70	1.72	1.06^d
	α-tocopherol	28.3	25.7^e	22.5^d
	Total tocopherols	30.5	28.0	23.9^d
Vitamin C (μmol/L)	Ascorbic acid	46.8	31.9^d	23.3^d
Total antioxidant capacity (μmol/L)	FRAP	1055	988^e	979
	Modified FRAP	336	170^d	166
Total GSH (μmol/L)		5.94	5.87	5.63
Total cysteine (μmol/L)		247.1	236.6^e	235.3
GSH redox potential (mV)		n.a.	-148	-147

^aMean values
^bPre-radiotherapy levels are compared with healthy controls after adjusting for age and BMI
^cPre- and post- radiotherapy levels are compared
^dp < 0.001, ^ep < 0.05
n.a. = not available

ISSN: 1471-2407