Balancing zinc deficiency leads to an improved healing of colon anastomosis in rats.
BACKGROUND
In colorectal surgery, anastomotic leakage is a relevant complication. The aim of this study was to investigate whether intraperitoneally (i.p.) administered zinc improves the healing of colon anastomosis in rats.


METHODS
Male Wistar rats (66) received zinc-deficient diet for 21 days. To determine the effective dose of zinc which is necessary to compensate this deficiency, preliminary analysis in 30 rats were performed. In these rats, analysis by atom-absorption spectrophotometry revealed a dose of 1.0 mg zinc aspartate/kg body weight to be the compensatory dosage. In the remaining zinc-deficient rats (n= 36), a transverse colonic anastomosis was performed. Eighteen rats received either a zinc supplementation i.p. or 0.9% NaCl i.p. (n = 18; control group). On postoperative days 3, 5, and 14, the surface of the mucosal villi, expression of MMP 2, MMP 8, MMP 13, TIMP 1, as well as the collagen types I/III ratio were analyzed.


RESULTS
Protein expression of MMP 2 and MMP 8 was significantly higher in the anastomosis of the zinc group on day 3 and on day 5. The collagen types I/III ratio was significantly increased in the zinc group on days 5 and 14.


CONCLUSIONS
Balancing zinc deficiency benefits wound healing of colonic anastomosis qualitatively due to an increased collagen type I/III ratio. Surprisingly, these zinc supplements, however, increased the expression of MMP 2 and MMP 8 that are supposed to impair wound healing in case of an over-expression. Thus, further investigations are needed to elucidate the influence of zinc supplementation on regulation of MMPs.
Grommes
Jochen
J
Department of Vascular Surgery, RWTH Aachen University Hospital, Pauwelsstr 30, 52074 Aachen, Germany. jgrommes@ukaachen.de
Binnebösel
Marcel
M
Klink
Christian D
CD
von Trotha
Klaus Thilo
KT
Rosch
Rafael
R
Oettinger
Alexander P
AP
Lindlar
Ines
I
Krones
Carsten J
CJ
D000714:Anastomosis, Surgical; D000818:Animals; D024042:Collagen Type I / Q000378:metabolism; D024061:Collagen Type III / Q000378:metabolism; D003106:Colon / Q000201:enzymology / Q000473:pathology*; D007413:Intestinal Mucosa / Q000201:enzymology / Q000473:pathology; D008297:Male; D020782:Matrix Metalloproteinases / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism; D014945:Wound Healing; D015032:Zinc / Q000172:deficiency*
D024042:Collagen Type I; D024061:Collagen Type III; D019714:Tissue Inhibitor of Metalloproteinases; D020782:Matrix Metalloproteinases; D015032:Zinc