Short-chain fatty acid-supplemented total parenteral nutrition improves nonspecific immunity after intestinal resection in rats.
BACKGROUND
Total parenteral nutrition (TPN) alters both specific and nonspecific immune functions, resulting in immunosuppression. Short-chain fatty acids have been shown to improve the adaptive responses of the gut after surgery. The following study investigates the effects of adding short-chain fatty acids to TPN on the immune system after an 80% small bowel resection.


METHODS
Rats (237 +/- 3 g) were infused with either TPN (n = 25) or TPN supplemented with short-chain fatty acids (n = 26) for 3 or 7 days. Hematologic analysis was performed on peripheral blood and splenocytes were isolated to characterize cell phenotypes, natural killer cell cytotoxicity and to estimate proliferative response.


RESULTS
The relative percent of T (CD3+) cells increased (p < .05) and the relative percent of macrophages decreased (p < .001, n = 13) in the spleens of the 3-day TPN-fed rats. By day 7, these differences disappeared. The natural killer cells from rats that were supplemented with short-chain fatty acids had higher (p < .0001) cytotoxic activity than the TPN groups at day 3. Mitogenic response did not differ between groups but were depressed compared with sham-treated rats. By day 7, rats on standard TPN had larger (p < .0001) spleens than all other groups. This group also had a higher total white blood cell count because of increased numbers of macrophages and neutrophils (p < .02).


CONCLUSIONS
Short-chain fatty acids improve components of nonspecific immune responses and may be beneficial in reducing certain aspects of TPN-associated immunosuppression after major surgery.
Pratt
V C
VC
Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Canada.
Tappenden
K A
KA
McBurney
M I
MI
Field
C J
CJ
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D005232:Fatty Acids, Volatile / Q000008:administration & dosage* / Q000276:immunology*; D007111:Immunity, Cellular / Q000187:drug effects*; D007422:Intestines / Q000276:immunology / Q000601:surgery; D007694:Killer Cells, Natural / Q000276:immunology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010289:Parenteral Nutrition, Total; D010641:Phenotype; D011184:Postoperative Period; D051381:Rats; D017207:Rats, Sprague-Dawley; D013154:Spleen / Q000187:drug effects* / Q000276:immunology*
D005232:Fatty Acids, Volatile