肥胖型多囊卵巢综合征患者血清左旋肉毒碱水平的变化及意义
2017-06-03王菲刘亚萍
王菲++刘亚萍
[摘要] 目的 探討肥胖型多囊卵巢综合征(PCOS)患者血清左旋肉毒碱水平的变化及意义。 方法 选取2014年5月~2016年9月内蒙古医科大学附属医院妇产科门诊确诊的PCOS患者60例,依据体重指数(BMI)分为非肥胖PCOS组(BMI<30 kg/m2,n=32)及肥胖PCOS组(BMI≥30 kg/m2,n=28)。选取同期就诊的28例月经周期规律的生育期妇女为对照组。采用酶联免疫吸附试验测定血清左旋肉毒碱水平,并分析其与肥胖、胰岛素抵抗及性激素的相关性。 结果 与非肥胖PCOS组比较,肥胖PCOS组的BMI、腰臀比及Ferriman-gallwey评分均升高,多毛症状人数增多,差异有统计学意义(P < 0.05)。与对照组比较,非肥胖PCOS组、肥胖PCOS组的多毛症状、不规则月经及月经周期紊乱增多,Ferriman-gallwey评分升高,差异有统计学意义(P < 0.05)。与非肥胖PCOS组比较,肥胖PCOS组的HOMA-IR及胰岛素抵抗例数升高,左旋肉毒碱水平降低,差异有统计学意义(P < 0.05)。与对照组比较,非肥胖、肥胖PCOS组的左旋肉毒碱水平降低,肥胖PCOS组的HOMA-IR及胰岛素抵抗例数升高,差异有统计学意义(P < 0.05)。肥胖PCOS患者血清左旋肉毒碱水平与BMI及HOMA-IR呈负相关(P < 0.05),而与E2、睾酮、FSH、DHEAS等指标无相关性(P > 0.05)。 结论 血清左旋肉毒碱水平在肥胖型PCOS患者中降低,且与BMI及HOMA-IR呈负相关,提示其可能参与疾病进程。
[关键词] 多囊卵巢综合征;左旋肉毒碱;肥胖;胰岛素抵抗
[中图分类号]R711 [文献标识码] A [文章编号] 1673-7210(2017)04(c)-0109-04
[Abstract] Objective To discuss the changes and significance of plasma L-carnitine levels of patients with obese polycystic ovary syndrome (PCOS). Methods 60 diagnosed patients with PCOS in Affiliated Hospital of Inner Mongolia Medical University from May 2014 to September 2016 were selected and divided into non obese PCOS group (BMI <30 kg/m2, n = 32)and obese PCOS group (BMI≥30 kg/m2, n=28) according to BMI. 28 cases of menstrual cycle were selected as control group. The plasma L-carnitine levels were determined by enzyme-linked immunosorbent assays. And its correlation with obesity, insulin resistance and sex hormones were analyzed. Results Compared with non-obesity PCOS group, BMI, waist/hip ratio, Ferriman-gallwey score of obesity PCOS group were increased and the number of hirsutism was increased, the differences were statistically significant (P < 0.05). Compared with control group, the febrile symptoms, irregular menstruation and menstrual cycle disorder, Ferriman-gallwey scores in non-obese PCOS group, obese PCOS group were increased, the differences were statistically significant (P < 0.05). Compared with non-obese PCOS group, HOMA-IR and insulin resistance in obese PCOS group were increased, and the level of L-carnitine was decreased, the differences were statistically significant (P < 0.05). Compared with control group, the levels of L-carnitine in non-obese PCOS group and obese PCOS group were decreased, and the number of HOMA-IR and insulin resistance in obese PCOS group were higher, the differences were statistically significant (P < 0.05). There was negative correlation between serum L-carnitine level and BMI, HOMA-IR in obese PCOS patients (P < 0.05), the levels of serum L-carnitine in obese PCOS patients were not correlated with E2, testosterone, FSH and DHEAS (P > 0.05). Conclusion Serum L-carnitine levels are reduced in obese PCOS patients and negatively correlated with BMI and HOMA-IR, suggesting that they may be involved in disease progression.
[Key words] Polycystic ovary syndrome; L-carnitine; Obesity; Insulin resistance
多囊卵巢综合征(PCOS)是妇科常见的一种内分泌疾病[1]。PCOS发病时多伴有糖脂质代谢紊乱等疾病,尤其是并发胰岛素抵抗相关的内脏型肥胖,30%~60%的PCOS患者超重或肥胖[2-3]。左旋肉毒碱是一种为人体代谢所必需的,在体内能量代谢中发挥重要作用的天然化合物[4]。研究表明,左旋肉毒碱参与动物体内脂肪酸[5]、葡萄糖代谢[6],而鲜有关于其在PCOS疾病进程的研究。因此,本研究通过检测肥胖及非肥胖PCOS患者左旋肉毒碱浓度,分析其与PCOS患者肥胖、胰岛素抵抗及性激素等的关系,探讨其在肥胖型PCOS发病中的作用。
1 资料与方法
1.1 一般资料
选取2014年5月~2016年9月于内蒙古医科大学附属医院妇产科门诊确诊的PCOS患者60例,依据体重指数(BMI)分为两组:非肥胖PCOS组(n=32),BMI<30 kg/m2,年龄22~39岁,平均(24.23±6.12)岁;肥胖PCOS组(n=28),BMI≥30 kg/m2,年龄21~38岁,平均(23.58±5.76)岁。选取同期就诊的28例月经周期规律的生育期妇女为对照组(n=28),年龄22~41岁,平均(23.16±5.82)岁。纳入标准:①PCOS诊断依据2003年10月ESHRE/ASRM鹿特丹会议上修订的PCOS诊断标准[7];多毛症采用Ferriman-gallwey评分标准[8];多囊卵巢指在B超下,检测到一侧卵巢有数量≥12个窦状卵泡(直径在2~9 mm)或和卵巢体积>10 mL可诊断为多囊卵巢[9]。②体重指数计算公式:BMI=体重(kg)/身高(m2)。BMI≥30 kg/m2认为肥胖,BMI<30 kg/m2认为非肥胖[10]。剔除标准:①非典型性先天性肾上腺增生症状;②伴有系统性疾病;③3个月内曾口服避孕药及影响内分泌的药物;④怀孕妇女。所有研究内容均经受试者知情同意且经医院伦理道德委员会批准实施。
1.2 研究方法
所有受试者均需隔夜禁食12 h后于次日早晨静脉抽血。血样经促凝处理,离心(4000 r/min,10 min)后,吸取上清,-80℃保存备用。检测内容:①采用化学发光免疫分析方法测定卵泡刺激素(FSH)、黄体生成素(LH)、促甲状腺激素(TSH)、催乳激素(PRL)、雌二醇(E2)、睾酮(T)、硫酸脱氢表雄烯二酮(DHEAS)、黄体酮及胰岛素(FINS)水平。②采用酶联免疫吸附试验(ELISA)测定血清左旋肉毒碱水平(上海心语生物科技有限公司);测定的线性范围0.5~100.0 μmol/L,组内及组间变异系数均<5%。③根据公式计算游离睾酮(FT),稳态模型评估的胰岛素抵抗指数(HOMA-IR)。
1.3 统计学方法
采用SPSS 13.0统计软件对数据进行分析和处理,计量资料以均数±标准差(x±s)表示,采用方差分析,计数资料采用χ2检验,相关性采用Spearman相关分析,以P < 0.05为差异有统计学意义。
2 结果
2.1 各组一般临床资料比较
与非肥胖PCOS组比较,肥胖PCOS组的BMI、腰臀比及Ferriman-gallwey评分均升高,多毛症状人数增多,差异有统计学意义(P < 0.05)。与对照组比较,非肥胖、肥胖PCOS组的多毛症状、不规则月经及月经周期紊乱增多,Ferriman-gallwey评分升高,差异有统计学意义(P < 0.05)。见表1。
2.2 各组相关检测指标情况比较
与非肥胖PCOS组比较,肥胖PCOS组的HOMA-IR及胰岛素抵抗例数升高,左旋肉毒碱水平降低,差异有统计学意义(P < 0.05)。与对照组比较,非肥胖、肥胖PCOS组的左旋肉毒碱水平降低,肥胖PCOS组的HOMA-IR及胰岛素抵抗例数升高,差异有统计学意义(P < 0.05)。当控制肥胖(BMI≥30 kg/m2)和增加腰臀比(> 0.85)作为混杂因素,PCOS患者与对照组的血清左旋肉毒碱水平比较,差异无统计学意义(P > 0.05)。见表2。
2.3 肥胖PCOS患者血清左旋肉毒碱水平与部分指标间的相关性分析
肥胖PCOS患者血清左旋肉毒碱水平与BMI及HOMA-IR呈负相关(P < 0.05),而与E2、睾酮、FSH、DHEAS等指标无相关性(P > 0.05)。见表3。
3 讨论
肉毒碱是一种有利于机体的生长发育和脂质代谢的非必需氨基酸。其生物活性形式为左旋肉毒碱。左旋肉毒碱的主要功能是转运长链脂肪酸至线粒体膜用于氧化反应[11]。此外,左旋肉毒碱还促进组织对葡萄糖的摄取并提高胰岛素的敏感性[12]。若给予2型糖尿病患者左旋肉毒碱治疗,则显著改善胰岛素抵抗症状[13-14]。
胰岛素抵抗和高胰岛素血症及肥胖能影响PCOS进程,是PCOS的显著特征之一[15]。研究证实,PCOS患者容易并发胰岛素抵抗及肥胖,同时胰岛素抵抗又与PCOS患者的雄激素过多显著相关[16-17]。本研究结果显示,肥胖PCOS患者的Ferriman-gallwey评分较非肥胖及对照组升高,且临床表现出多毛症状、不规则月经及月经周期紊乱等现象。同时,肥胖PCOS患者具有较高的HOMA-IR及胰岛素抵抗人数,这可能与肥胖PCOS患者体内的胰岛素抵抗与雄激素过多间相互作用,往往形成恶性循环,造成其他内分泌及代谢并发症的发生及持续损害,但其他性激素水平变化不大,可能与样本量偏少有关。
研究表明,较低的血清左旋肉毒碱水平与胰島素抵抗呈负相关[18]。酰基肉毒碱为肉毒碱的前体,是脂肪酸氧化过程中合成的中间体。较高的果糖代谢水平造成胰岛素抵抗,抑制酰基肉毒碱的产生[19]。因此,肥胖及胰岛素抵抗症状患者具有较高的酰基肉毒碱水平,而血清左旋肉毒碱水平则降低。而增加血清左旋肉毒碱的水平可能有利于改善糖耐受及胰岛素敏感性[20]。本研究结果显示,与非肥胖PCOS患者及对照组比较,肥胖PCOS患者具有较高的HOMA-IR及胰岛素抵抗人数及较低的左旋肉毒碱水平。当控制肥胖(BMI≥30 kg/m2)和增加腰臀比(> 0.85)作为混杂因素,PCOS患者与对照组人群的血清左旋肉毒碱水平比较,差异无统计学意义。相关性分析结果表明,肥胖型PCOS患者血清左旋肉毒碱水平与BMI及HOMA-IR呈负相关。这再次证实左旋肉毒碱对胰岛素抵抗产生积极的作用。Fenkci等[21]研究结果提示,对照组人群血清左旋肉毒碱水平较PCOS患者增高,较低的血清左旋肉毒碱水平与PCOS的肥胖相关,但Fenkci等[21]认为左旋肉毒碱和肥胖与PCOS相关较胰岛素抵抗或单纯肥胖相关更有意义。
綜上所述,本研究揭示左旋肉毒碱在肥胖型PCOS患者中的水平变化情况,但目前关于左旋肉毒碱在PCOS进程中的作用及与PCOS患者代谢异常相关性的研究报道较少且不一致,有待今后的进一步研究。本研究还存在样本量偏少,导致PCOS患者性激素相关指标的浓度变化不明显,故后续将扩大样本量深入研究,为探讨PCOS发病机制及治疗提供更多的理论依据,从而为PCOS的防治提供新的思路。
[参考文献]
[1] Andrade VH,Mata AM,Borges RS,et al. Current aspects of polycystic ovary syndrome:a literature review [J]. Rev Assoc Med Bras,1992,2016,62(9):867-871.
[2] Csenteri OK,Sándor J,Kalina E,et al. The role of hyperinsulinemia as a cardiometabolic risk factor independent of obesity in polycystic ovary syndrome [J]. Gynecol Endocrinol,2017,33(1):34-38.
[3] Riley JK,Jungheim ES. Is there a role for diet in ameliorating the reproductive sequelae associated with chronic low-grade inflammation in polycystic ovary syndrome and obesity? [J]. Fertil Steril,2016,106(3):520-527.
[4] Pooyandjoo M,Nouhi M,Shab-Bidar S,et al. The effect of(L-)carnitine on weight loss in adults:a systematic review and meta-analysis of randomized controlled trials [J]. Obes Rev,2016,17(10):970-976.
[5] Eleftheriadis T,Pissas G,Sounidaki M,et al. Indoleamine 2,3-dioxygenase,by degrading L-tryptophan,enhances carnitine palmitoyltransferase I activity and fatty acid oxidation,and exerts fatty acid-dependent effects in human alloreactive CD4+ T-cells [J]. Int J Mol Med,2016,38(5):1605-1613.
[6] Galloway SD,Craig TP,Cleland SJ. Effects of oral L-carnitine supplementation on insulin sensitivity indices in response to glucose feeding in lean and overweight/obese males [J]. Amino Acids,2011,41(2):507-515.
[7] Rotterdam ESHRE/ASRM-Sponsored PCOS consensus workshop group. Revised 2003 consensus on diagnostic criteria and long-term health risks related to polycystic ovary syndrome (PCOS) [J]. Hum Reprod,2004,19(1):41-47.
[8] Spritzer PM,Barone CR,Oliveira FB. Hirsutism in Polycystic Ovary Syndrome: Pathophysiology and Management [J]. Curr Pharm Des,2016,22(36):5603-5613.
[9] 闫景彬,陈仙秋,杨建京,等.B超诊断非赘生性卵巢囊肿的临床应用[J].中国计划生育学杂志,2014,22(11):762-764.
[10] 中国肥胖问题工作组数据汇总分析协作组.我国成人体重指数和腰围对相关疾病危险因素异常的预测价值:适宜体重指数和腰围切点的研究[J].中华流行病学杂志,2002,23(1):5-10.
[11] Evans AM,Fornasini G. Pharmacokinetics of L-carnitine [J]. Clin Pharmacokinet,2003,42(11):941-967.
[12] El-Hattab AW,Scaglia F. Disorders of carnitine biosynthesis and transport [J]. Mol Genet Metab,2015,116(3):107-112.
[13] Abdali D,Samson SE,Grover AK. How effective are antioxidant supplements in obesity and diabetes? [J]. Med Princ Pract,2015,24(3):201-215.
[14] McCoin CS,Knotts TA,Adams SH. Acylcarnitines——old actors auditioning for new roles in metabolic physiology [J]. Nat Rev Endocrinol,2015,11(10):617-625.
[15] Moghetti P. Insulin resistance and polycystic ovary syndrome [J]. Curr Pharm Des,2016,22(36):5526-5534.
[16] Pauli JM,Raja-Khan N,Wu X,et al. Current perspectives of insulin resistance and polycystic ovary syndrome [J]. Diabet Med,2011,28(12):1445-1454.
[17] Sirmans SM,Pate KA. Epidemiology,diagnosis,and management of polycystic ovary syndrome [J]. Clin Epidemiol,2013,6(1):1-13.
[18] Ruggenenti P,Cattaneo D,Loriga G,et al. Ameliorating hypertension and insulin resistance in subjects at increased cardiovascular risk:effects of acetyl-L-carnitine therapy [J]. Hypertension,2009,54(3):567-574.
[19] Power RA,Hulver MW,Zhang JY,et al. Carnitine revisited:potential use as adjunctive treatment in diabetes [J]. Diabetologia,2007,50(4):824-832.
[20] Vidal-Casariego A,Burgos-Peláez R,Martínez-Faedo C,et al. Metabolic effects of L-carnitine on type 2 diabetes mellitus:systematic review and meta-analysis [J]. Exp Clin Endocrinol Diabetes,2013,121(4):234-238.
[21] Fenkci SM,Fenkci V,Oztekin O,et al. Serum total L-carnitine levels in non-obese women with polycystic ovary syndrome [J]. Hum Reprod,2008,23(7):1602-1606.
(收稿日期:2017-01-09 本文編辑:李亚聪)