Modification of brain function regulating metabolism by antisense oligodeoxynucleotides

在下丘脑腹内侧核(VMH)，γ-氨基丁酸(GABA)起着重要的代谢调节作用。GABA合成酶谷氨酸脱羧酶(GAD)由GAD65和GAD67两种同工酶组成。本研究观察了在雄性大鼠VMH各GAD同工酶上注射反义寡核苷酸(ODN)对大鼠摄食量、体重和运动能力的影响。将硫代反义寡核苷酸掺入吸水性聚合物(WAP)中，注射入双侧VMH，以注射当天为第0天。GAD65和GAD67的反义寡核苷酸有减少第1天摄食量的趋势，但并不显著。同时向两种GAD同工酶注射反义ODN仅在第1天显著减少摄食量，但这种处理持续5天仍能抑制体重。另一方面，同时给予GAD65和GAD67反义寡核苷酸显著增加LOCO…在第3-5天期间有更多的运动活动，而其他治疗没有。这种日常运动活动的增加主要是由于在光明阶段而不是黑暗阶段运动活动的增加。载体(WAP)和对照ODN都不影响摄食量、体重和运动活动。组织学研究表明，注射后24 h，反义ODN分布于WAP所在区域边缘约800 nm范围内，并随时间推移逐渐消失，但在注射后7 d仍保持在300 um范围内。反义ODN能有效地被所有细胞类型，即神经元、星形胶质细胞和小胶质细胞所掺入。进一步的高效液相色谱分析表明，反义GAD同工酶能降低VMH中GABA的含量，但不影响VMH中其他氨基酸的含量，提示这两种GAD同工酶在增加大鼠VMH的摄食量和抑制动物的运动活动方面具有协同作用。较少

In the ventromedial nucleus of the hypothalamus (VMH), gamma-aminobutyric acid (GABA) plays an important role in regulating metabolism. The GABA synthetic enzyme, glutamic acid decarboxylase (GAD) consists of two isozymes, GAD65 and GAD67. In the present study, the effect of injection of antisense oligodeoxynucleotides (ODNs) to each GAD isozyme into the VMH of the male rat on food intake, body weight and locomotor activity was examined. Phosphorothioated antisense ODNs were incorporated in the water-absorbent polymer (WAP) and injected into bilateral VMH,and the day of injection was designated as day 0. Antisense ODNs to GAD65 and GAD67 tended to reduce food intake on day 1, though not significant. Simultaneous injection of antisense ODNs to both GAD isozymes significantly decreased food intake on only day 1, but body weight remained suppressed by this treatment for 5 days. On the other hand, simultaneous administration of antisense ODNs to GAD65 and GAD67 significantly increased loco … More motor activity between days 3-5, whcreas other treatments did not. This increase in daily locomotor activity was mainly due to the increase in locomotor activity during the light, but not dark, phase. Neither vehicle (WAP) nor control ODN affected food intake, body weight and locomotor activity. Histological studies indicated that, 24 h after the injection, antisense ODN distributed within about 800 mum from the edge of area where WAP was located and then gradually disappeared with days, but still remained within 300 mum distance even 7 days after the injection. Antisense ODN was effectively incorporated by all the cell types examined, i.e.neurons, astrocytes and microglias. Further, HPLC analysis revealed that antisense ODN to either GAD isozyme decreased the content of GABA,but not other amino acids, in the VMH by 24 h. These results suggest that either GAD isozyme is synergistically involved in enhancing food intake and suppressing locomotor activity in rat VMH.This study also indicates that central injection of antisense oligodeoxynucleotides is useful means to regulate animal metabolism. Less