| Disease | IN A CROSS-SECTIONAL, PLACEBO-CONTROLLED, DOUBLE-BLIND STUDY WE EXAMINED THE EFFECT OF 10-12 Y OF BETA-CAROTENE SUPPLEMENTATION (50 MG ON ALTERNATE DAYS) ON NK CELL ACTIVITY IN 59 (38 MIDDLE-AGE MEN, 51-64 Y; 21 ELDERLY MEN, 65-86 Y) BOSTON
AREA PARTICIPANTS IN PHYSICANS' HEALTH STUDY. NO SIGNIFICANT DIFFERENCE WAS SEEN IN NK CELL ACTIVITY DUE TO BETA-CAROTENE SUPPLEMENTATION IN THE MIDDLE-AGE GROUP. THE ELDERLY MEN HAD SIGNIFICANTLY LOWER NK CELL ACTIVITY THAN THE MIDDLE-AGED
MEN; HOWEVER, THERE WAS NO AGE-ASSOCIATED DIFFERENCE IN NK CELL ACTIVITY IN MEN SUPPLEMENTED WITH BETA-CAROTENE. BETA-CAROTENE-SUPPLEMENTED ELDERLY MEN HAD SIGNIFICANLY GREATER NK CELL ACTIVITY THAN ELDERLY MEN REDEIVING PLACEBO. THE REASON
FOR THIS IS UNKNOWN; HOWEVER, IT WAS NOT DUE TO INCREASE IN THE PERCENTAGE OF NK CELLS, NOR TO AN INCREASE IN INTERLEUKIN 2 (IL-2) RECEPTOR EXPRESSION, NOR TO IL-2 PRODUCTION. BETA-CAROTENE MAY BE ACTING DIRECLY ON ONE OR MORE OF THE LYTIC
STAGES OF NK CELL CYTOTOXICITY, OR ON NK CELL ACTIVITY-ENHANCING CYTOKINES OTHER THAN IL-2, SUCH IL-12. OUR RESULTS SHOW THAT LONG-TERM BETA-CAROTENE SUPPLEMENTATION ENHACES NK CELL ACTIVITY IN ELDERLY MEN, WHICH MAY BE BENEFICIAL FOR VIRAL
AND TUMORAL SURVEILLANCE. |