Increased intake of
vitamin E has been suggested to be protective against
prostate cancer in men, but the effects of
vitamin E on prostate growth and function remain poorly defined. The purpose of this study was to determine the effects of
vitamin E deficiency on pubertal growth and maturation of the prostate in the rat. Animals were placed on a
vitamin E deficient diet at 28 days of age and were followed for 15 and 26 weeks.
Vitamin E deficient rats had a circulating
vitamin E level of less than 1% of control animals and experienced a decrease in body and testis weight. The deficiency did not alter the weights of the ventral and dorsal lobes of the prostate. However, there was an increase in weight,
DNA, and
protein contents of the lateral lobe in control and
vitamin E deficient rats from 15 to 26 weeks of treatment, but these increases were significantly lower in
vitamin E deficient 26-week treated rats. The volume of secretion per milligram tissue was greater in the ventral than lateral or dorsal lobes. The volume of secretion and activity of the secretory 26 kDa
protease in the ventral prostate was lower in
vitamin E deficient rats at 15 weeks, but not at 26 weeks of treatment. In contrast, the relative
protein content of lateral lobe secretion increased in both control and
vitamin E deficient rats from 15 to 26 weeks of treatment. The lateral, but not ventral or dorsal, lobes of both control and
vitamin E deficient rats were affected by chronic
prostatitis as evidenced by infiltration of inflammatory cells. The lateral lobes also showed markedly elevated activities of the
matrix metalloproteinases gelatinase A (MMP-2) and
gelatinase B (MMP-9). These data indicate that
vitamin E deficiency does not alter the growth of the prostatic lobes, nor the onset and extent of lateral lobe specific
prostatitis, but it may delay some differentiated functions such as secretion of specific
proteins in the ventral lobe. Thus, the effects of
vitamin E in the prostate of the rat appear to be selective.