Flechtner-Mors M, Ditschuneit H H, Jenkinson C P, Alt A, Adler G
Department of Internal Medicine, University of Ulm, Germany.
Diabet Med. 1999 Dec;16(12):1000-6. doi: 10.1046/j.1464-5491.1999.00189.x.
Metformin has been reported to decrease the plasma concentrations of non-esterified fatty acids in Type 2 diabetic subjects. This study investigated the effects of metformin on basal and catecholamine-stimulated lipolysis in abdominal subcutaneous adipose tissue of obese, hyperinsulinaemic, hypertensive subjects.
Fourteen subjects with severe obesity (12 female, twomale, age 35.4 +/- 4 years, body mass index 48.2 +/- 2 kg/m2, body fat mass 63.3 +/- 5 kg) were recruited. Glycerol and lactate concentrations were determined in the presence of metformin and after administration of catecholamines using microdialysis. Simultaneously, blood flow was assessed with the ethanol escape method.
Glycerol release was lowered by metformin during the 3-h experiment (P<0.01). The lipolytic activity of catecholamines was suppressed when adipose tissue was pre-treated with metformin (P<0.001). Lactate concentration increased after application of metformin (P<0.01) and catecholamines (P<0.001). Blood flow was decreased in the presence of adrenaline (P < 0.01), but this effect was abolished by metformin.
The present data demonstrate the effects of metformin on lipolysis in subcutaneous adipose tissue in vivo. In the large body fat mass of obese subjects, a reduction of lipolysis in adipose tissue may contribute to a decrease of VLDL synthesis in the liver resulting in a lowered plasma triglyceride concentration.
据报道，二甲双胍可降低2型糖尿病患者血浆中非酯化脂肪酸的浓度。本研究调查了二甲双胍对肥胖、高胰岛素血症、高血压患者腹部皮下脂肪组织基础和儿茶酚胺刺激的脂肪分解的影响。
招募了14名严重肥胖受试者（12名女性，2名男性，年龄35.4±4岁，体重指数48.2±2kg/m²，体脂肪量63.3±5kg）。使用微透析法在存在二甲双胍的情况下以及给予儿茶酚胺后测定甘油和乳酸浓度。同时，用乙醇洗脱法评估血流量。
在3小时实验期间，二甲双胍降低了甘油释放量（P<0.01）。当脂肪组织用二甲双胍预处理时，儿茶酚胺的脂解活性受到抑制（P<0.001）。应用二甲双胍（P<0.01）和儿茶酚胺（P<0.001）后，乳酸浓度升高。存在肾上腺素时血流量减少（P<0.01），但这种作用被二甲双胍消除。
目前的数据证明了二甲双胍对体内皮下脂肪组织脂肪分解的影响。在肥胖受试者的大量体脂肪中，脂肪组织中脂肪分解的减少可能有助于肝脏中极低密度脂蛋白合成的减少，从而导致血浆甘油三酯浓度降低。
