Plasma (carotenoids, retinol, α-tocopherol) and tissue (carotenoids) levels after supplementation with β-carotene in subjects with precancerous and cancerous lesions of sigmoid colon

• Published in: European journal of clinical nutrition Vol. 51; no. 10; pp. 661 - 666
• Main Authors: Pappalardo, G, Maiani, G, Mobarhan, S, Guadalaxara, A, Azzini, E, Raguzzini, A, Salucci, M, Serafini, M, Trifero, M, Illomei, G, Ferro-Luzzi, A
• Format: Journal Article
• Language: English
• Published: Basingstoke Nature Publishing 01.10.1997; Nature Publishing Group
• Subjects: Adenomatous Polyposis Coli; Adenomatous Polyposis Coli - blood; Adenomatous Polyposis Coli - metabolism; administration & dosage; Adult; Aged; Antioxidants; beta Carotene; beta Carotene - administration & dosage; beta Carotene - blood; beta Carotene - metabolism; Biological and medical sciences; Biopsy; blood; blood plasma; Cancer; Carotene; Carotenoids; Carotenoids - blood; Carotenoids - metabolism; Colon; Colonic Neoplasms; Colonic Neoplasms - blood; Colonic Neoplasms - metabolism; Colorectal cancer; Dietary supplements; Female; Gastroenterology. Liver. Pancreas. Abdomen; High performance liquid chromatography; Humans; Intestines; Intestines - metabolism; Lesions; Liquid chromatography; Lycopene; Male; Malformations; Medical sciences; metabolism; Middle Aged; Mucosa; neoplasms; Nutrition; Plasma; Plasma levels; Polyps; Precancerous Conditions; Precancerous Conditions - blood; Precancerous Conditions - metabolism; Stomach. Duodenum. Small intestine. Colon. Rectum. Anus; Tissues; Tocopherol; Vitamin A; Vitamin A - blood; Vitamin E; Vitamin E - blood; vitamin supplements; Zeaxanthin; β-Carotene; Human; Gut; Exploration; α-Tocopherol; Malignant tumor; Blood plasma; Retinol; Tissue; Digestive diseases; Intestinal disease; Betacarotene; Supplementation; Carotenoid
• ISSN: 0954-3007; 1476-5640
• DOI: 10.1038/sj.ejcn.1600457

(1) To compare tissue and plasma carotenoids status of healthy subjects and subjects with pre-cancer and cancer lesions; (2) to evaluate the effect of beta-carotene supplementation on the concentrations of other carotenoids in tissue (luteine + zeaxanthin, cryptoxanthin, lycopene, alpha-carotene) and in plasma and also retinol and alpha-tocopherol levels. Eighteen subjects were divided into three groups on the basis of colonoscopy and histological analytical findings: four healthy subjects (control group A); seven subjects affected by adenomatous polyps (group B with pre-cancer lesions); seven subjects suffering from colonic cancer (group C). Blood and colonic biopsy samples were taken (of colon and rectal mucosa) before and after beta-carotene supplementation in all subjects. Groups A and B received a daily dose of beta-carotene (30 mg/die) for 43 d. Group C's supplementation was terminated at the time which was performed, usually within 15 d. The tissue and plasma concentration of carotenoids, retinol and alpha-tocopherol were determined by high-performance liquid chromatography. The tissue concentrations of each carotenoid were similar in all the intestinal sites examined as regards groups A and B, although there was a high degree of intra individual variability within each group. Only beta-carotene made significant increases (P < 0.001) after supplementation. The subjects with cancer show tissue levels for each carotenoid lower than those of healthy subjects or subjects with polypous. The plasma levels of alpha-tocopherol did not change after supplementation while significant increases were noted of retinol, alpha-carotene (P < 0.01) and of beta-carotene (P < 0.001). The patients with colonic cancer seemed to undergo a significant reduction in their antioxidant reserves with respect to the normal subjects and or polyps. We can confirm that oral B-carotene supplementation induces also an increase in plasma alpha-carotene in all groups.