Effect of tumor weight and tube feeding on TNF-alpha and IL-1beta mRNA expression in the brain of mice.
BACKGROUND
Previous studies have shown that cytokine mRNA expression is elevated in the brains of anorectic, tumor-bearing rats. The objectives of the current study were as follows: (1) to determine whether a small tumor would result in up-regulation of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta mRNA expression in the brain and other tissues of tumor-bearing mice; and (2) to determine whether hyperalimentation by tube feeding would prevent up-regulation of cytokine mRNA expression in the brain and other tissues of tumor-bearing mice.


METHODS
Male C57BL/6 mice were divided into 4 groups: (1) control mice fed ad libitum (Control); (2) tumor-bearing mice fed ad libitum (TB); (3) control mice receiving tube feeding (CTF); and (4) tumor-bearing mice receiving tube feeding (TBTF).


RESULTS
TNF-alpha and IL-1beta mRNA expression was elevated in the brains of mice with a 1% body weight tumor, relative to the control and CTF groups, without any detectable changes in the other organs. On the other hand, TNF-alpha and IL-1beta mRNA expression was elevated in all organs of mice with an 8% body weight tumor, relative to the control and CTF groups. Tube feeding did not change TNF-alpha and IL-1beta mRNA expression in mice burdened with either a 1% or 8% body weight tumor.


CONCLUSIONS
Up-regulation of cytokine mRNA synthesis occurs earlier in the brain than in other organs, and hyperalimentation does not change cytokine mRNA expression in tumor-bearing mice.
Ozaki
K
K
Department of Surgery, Kurume University, School of Medicine, Fukuoka, Japan.
Yoshida
S
S
Ishibashi
N
N
Kamei
H
H
Muraoka
T
T
Shirouzu
K
K
D000818:Animals; D001835:Body Weight; D001921:Brain / Q000378:metabolism*; D004750:Enteral Nutrition / Q000009:adverse effects*; D015972:Gene Expression Regulation, Neoplastic; D007375:Interleukin-1 / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D012333:RNA, Messenger / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
D007375:Interleukin-1; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha