Effects of different doses of fish oil on rectal cell proliferation in patients with sporadic colonic adenomas.
OBJECTIVE
Fish oil supplementation can reduce cytokinetic anomalies in the flat rectal mucosa of patients with sporadic colorectal adenoma. This study attempted to identify an optimum dose for fish oil supplementation and evaluate the persistence of its effects during long-term administration.


METHODS
In a double-blind study, 60 patients with sporadic adenomas received 2.5, 5.1, or 7.7 g of fish oil per day or placebo for 30 days. [3H]thymidine autoradiographic labeling indices were calculated in flat rectal mucosal biopsy specimens collected before and after supplementation. In a subsequent study, 15 patients with polyps received 2.5 g of fish oil per day. Proliferative parameters, mucosal fatty acids, and mucosal and plasma alpha-tocopherol levels were evaluated before, during, and after 6 months of supplementation.


RESULTS
Mean proliferative indices and mucosal arachidonic acid levels decreased significantly (and to similar degrees) in all treated groups, whereas mucosal eicosapentaenoic and docosahexaenoic acid levels increased. Significantly reduced proliferation was observed only in patients with abnormal baseline patterns. These effects persisted during long-term, low-dose treatment. A transient reduction in mucosal (but not plasma) alpha-tocopherol levels was observed after 1 month of treatment. Side effects were insignificant.


CONCLUSIONS
Low-dose fish oil supplementation has short-term and long-term normalizing effects on the abnormal rectal proliferation patterns associated with increased colon cancer risk.
Anti
M
M
Department of Internal Medicine, Catholic University of Rome, Italy.
Armelao
F
F
Marra
G
G
Percesepe
A
A
Bartoli
G M
GM
Palozza
P
P
Parrella
P
P
Canetta
C
C
Gentiloni
N
N
De Vitis
I
I
D011125:Adenomatous Polyposis Coli / Q000178:diet therapy* / Q000378:metabolism / Q000473:pathology; D000368:Aged; D000704:Analysis of Variance; D002455:Cell Division; D004281:Docosahexaenoic Acids / Q000378:metabolism; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000378:metabolism; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage* / Q000627:therapeutic use; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012007:Rectum / Q000378:metabolism / Q000473:pathology*; D014810:Vitamin E / Q000378:metabolism
D005395:Fish Oils; D014810:Vitamin E; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid