ANBAS Corporation, 4-12-17, Toyosaki, Kita-Ku, Osaka 531-0072, Japan.
Neurosci Lett. 2012 Feb 21;510(1):1-5. doi: 10.1016/j.neulet.2011.12.058. Epub 2012 Jan 5.
l-Carnosine (β-alanyl-l-histidine), a dipeptide of the amino acids β-alanine and histidine, is found in mammalian tissues including those in the central nervous system and in skeletal muscles. In the present study, we examined the effects of intraduodenal (ID) injection of l-carnosine on splenic sympathetic nerve activity (splenic-SNA) in urethane-anesthetized rats and found that ID injection of 3.3mg/kg of body weight of l-carnosine significantly suppressed splenic-SNA. Since it has been suggested that splenic-SNA reduction increases natural killer (NK) activity of splenic cells, which in turn elevates tumor immunity, we then investigated the effect of l-carnosine on the proliferation of human colon cancer cells transplanted into athymic nude mice. The findings of this study revealed that 1mg/mL of l-carnosine solution given as the only drinking water inhibited tumor proliferation. These results suggest that l-carnosine suppresses splenic-SNA and inhibits cancer cell proliferation, probably by elevating NK activity.
l-肉碱（β-丙氨酸-l-组氨酸）是一种由β-丙氨酸和组氨酸组成的二肽，存在于哺乳动物组织中，包括中枢神经系统和骨骼肌。在本研究中，我们检查了十二指肠内（ID）注射 l-肉碱对麻醉大鼠脾交感神经活动（脾-SNA）的影响，发现 ID 注射 3.3mg/kg 的 l-肉碱体重显著抑制脾-SNA。由于有人认为脾-SNA 减少会增加脾细胞的自然杀伤（NK）活性，从而提高肿瘤免疫力，因此我们随后研究了 l-肉碱对移植到无胸腺裸鼠的人结肠癌细胞增殖的影响。这项研究的结果表明，仅作为饮用水的 1mg/mL l-肉碱溶液抑制肿瘤增殖。这些结果表明，l-肉碱抑制脾-SNA 并抑制癌细胞增殖，可能是通过提高 NK 活性。
