Anbarasi K, Vani G, Balakrishna K, Devi C S Shyamala
Department of Biochemistry, University of Madras, Guindy Campus, Chennai--600 025, India.
J Biochem Mol Toxicol. 2005;19(1):59-65. doi: 10.1002/jbt.20050.
Membrane-bound enzymes play a vital role in neuronal function through maintenance of membrane potential and impulse propagation. We have evaluated the harmful effects of chronic cigarette smoking on membrane-bound ATPases and the protective effect of Bacoside A in rat brain. Adult male albino rats were exposed to cigarette smoke for a period of 12 weeks and simultaneously administered with Bacoside A (the active principle isolated from Bacopa monniera) at a dosage of 10 mg/kg b.w/day, p.o. The levels of lipid peroxides as marker for evaluating the extent of membrane damage, the activities of Na+/K+-ATPase, Ca2+-ATPase and Mg2+-ATPase, and associated cations sodium (Na+), potassium (K+), calcium (Ca2+), and magnesium (Mg2+) were investigated in the brain. Neuronal membrane damage was evident from the elevated levels of lipid peroxides and decreased activities of membrane-bound enzymes. Disturbances in the electrolyte balance with accumulation of Na+ and Ca2+ and depletion of K+ and Mg2+ were also observed. Administration of Bacoside A inhibited lipid peroxidation, improved the activities of ATPases, and maintained the ionic equilibrium. The results of our study indicate that Bacoside A protects the brain from cigarette smoking induced membrane damage.
膜结合酶通过维持膜电位和冲动传播在神经元功能中发挥重要作用。我们评估了长期吸烟对大鼠脑内膜结合ATP酶的有害影响以及印度人参苷A的保护作用。成年雄性白化大鼠暴露于香烟烟雾中12周,同时以10mg/kg体重/天的剂量口服给予印度人参苷A(从假马齿苋中分离出的活性成分)。研究了脑内作为评估膜损伤程度标志物的脂质过氧化物水平、Na+/K+-ATP酶、Ca2+-ATP酶和Mg2+-ATP酶的活性以及相关阳离子钠(Na+)、钾(K+)、钙(Ca2+)和镁(Mg2+)。脂质过氧化物水平升高和膜结合酶活性降低表明神经元膜受到损伤。还观察到电解质平衡紊乱,Na+和Ca2+积累,K+和Mg2+耗竭。给予印度人参苷A可抑制脂质过氧化,提高ATP酶活性并维持离子平衡。我们的研究结果表明,印度人参苷A可保护大脑免受吸烟诱导的膜损伤。