Chauhan Ved P S, Tsiouris John A, Chauhan Abha, Sheikh Ashfaq M, Brown W Ted, Vaughan Michael
NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA.
Life Sci. 2002 May 31;71(2):153-61. doi: 10.1016/s0024-3205(02)01619-3.
During hibernation, animals undergo metabolic changes that result in reduced utilization of glucose and oxygen. Fat is known to be the preferential source of energy for hibernating animals. Malonyldialdehyde (MDA) is an end product of fatty acid oxidation, and is generally used as an index of lipid peroxidation. We report here that peroxidation of lipids is increased in the plasma and in the membranes of red blood cells in black bears during hibernation. The plasma MDA content was about four fold higher during hibernation as compared to that during the active, non-hibernating state (P < 0.0001). Similarly, MDA content of erythrocyte membranes was significantly increased during hibernation (P < 0.025). The activity of Ca(2+)/Mg(2+)-ATPase in the erythrocyte membrane was significantly decreased in the hibernating state as compared to the active state. Na(+)/K(+)-ATPase activity was also decreased, though not significant, during hibernation. These results suggest that during hibernation, the bears are under increased oxidative stress, and have reduced activities of membrane-bound enzymes such as Ca(2+)/Mg(2+)-ATPase and Na(+)/K(+)-ATPase. These changes can be considered part of the adaptive for survival process of metabolic depression.
在冬眠期间，动物会经历代谢变化，导致葡萄糖和氧气的利用率降低。脂肪是已知冬眠动物的优先能量来源。丙二醛（MDA）是脂肪酸氧化的终产物，通常用作脂质过氧化的指标。我们在此报告，冬眠期间黑熊血浆和红细胞膜中的脂质过氧化增加。与活跃的非冬眠状态相比，冬眠期间血浆MDA含量高出约四倍（P < 0.0001）。同样，冬眠期间红细胞膜的MDA含量显著增加（P < 0.025）。与活跃状态相比，冬眠状态下红细胞膜中Ca(2+)/Mg(2+)-ATP酶的活性显著降低。冬眠期间Na(+)/K(+)-ATP酶活性也有所下降，尽管不显著。这些结果表明，在冬眠期间，熊承受着增加的氧化应激，并且膜结合酶如Ca(2+)/Mg(2+)-ATP酶和Na(+)/K(+)-ATP酶的活性降低。这些变化可被视为代谢抑制生存过程适应性的一部分。
