H2型松弛素对慢性支气管哮喘小鼠气道重塑与肺组织细胞周期蛋白D1表达的影响

目的 研究H2型松弛素(H2Relaxin)对慢性支气管哮喘(简称哮喘)模型小鼠气道重塑及肺组织细胞周期蛋白D1 (cyclin D1)表达的影响,探素松弛素在哮喘治疗中的可能作用.方法 将40只BALB/c小鼠按随机数字表法分为健康对照组、哮喘组、阴性对照组(vehicle)、松弛素组4组,每组10只;卵清白蛋白(OVA)致敏、激发建立慢性哮喘小鼠模型;vehicle组和松弛素组每日分别给予生理盐水和松弛素(0.25 mg·kg-1 ·d-1)皮下注射.HE和马森(Masson)染色观察各组小鼠气道炎症及胶原沉积情况;采用免疫组织化学半定量法测定气道壁α-平滑肌肌动蛋白( α-SMA)的表达;酶联免疫吸附测定( ELISA)法检测肺组织羟脯氨酸含量;用逆转录-PCR(RT-PCR)及免疫印迹法(Western blot)分别测定各组小鼠肺组织中cyclin D1mRNA和蛋白表达水平.结果 哮喘组、vehicle 组与健康对照组相比,嗜酸粒细胞浸润增多,气道管腔狭窄,平滑肌层增厚,胶原纤维增生,而松弛素组上述改变较此2组轻.与健康对照组相比,哮喘组、vehicle组小鼠支气管α-SMA阳性染色面积/支气管基底膜周径显著增加(均P ＜0.05),松弛素组小鼠支气管α-SMA阳性染色面积/支气管基底膜周径低于哮喘组和vehicle组(均P＜0.05);哮喘组和vehicle组小鼠羟脯氨酸含量[每克肺组织中分别为(0.68±0.10)mg、(0.67±0.10) mg]高于健康对照组的(0.26±0.05)mg(q值分别为16.61和16.01,均P＜0.01),松弛素组小鼠羟脯氨酸含量为(0.40±0.06)mg,低于哮喘组和vehicle组(q值分别为10.88和10.26,均P＜0.05);Western blot检测结果显示,cyclin D1在哮喘组、vehicle组和松弛素组的表达(分别为1.38±0.18、1.50±0.10和0.72±0.13)高于健康对照组的0.38±0.10(q值分别为13.00、14.65和4.49,均P＜0.05),而松弛素组表达量低于哮喘组与vehicle组(q值分别为8.51和10.16,均P＜0.05).哮喘组与vehicle组各项检测指标间差异无统计学意义(P＞0.05).结论 松弛素可以显著减轻慢性哮喘小鼠气道炎症反应和平滑肌层的增厚,延缓哮喘小鼠气道重塑进程,该作用可能部分与其下调cyclin D1表达有关.     

Induction of labor with RU 486 (mifepristone) in relaxin-deficient rats: antepartum administration of relaxin facilitates delivery and increases pup survival

OBJECTIVE: This study was conducted to determine whether antepartum administration of relaxin improves RU 486-induced delivery at term in rats that lack circulating endogenous relaxin. STUDY DESIGN: Pregnant rats were modified two ways to obtain circulating levels of relaxin and progesterone that resemble those of pregnant humans: relaxin was immunoneutralized throughout the second half of the 23-day pregnancy and high progesterone levels were sustained until term by inserting progesterone implants on day 20. Porcine relaxin was administered subcutaneously from 8 AM on day 20 until delivery. Labor was induced by administering RU 486 subcutaneously at 4 AM on day 22. RESULTS: After induction of labor with RU 486, labor and delivery were faster, and the incidence of live births was higher when rats were also administered relaxin during the antepartum period. CONCLUSION: Antepartum administration of relaxin in combination with RU 486 has beneficial effects on delivery in relaxin-deficient rats.     

Synergistic effect of human relaxin and progesterone on human myometrial contractions

In an in vitro human myometrial strip system, both relaxin and progesterone can independently decrease the amplitude of spontaneous myometrial contractions. However, progesterone and relaxin synergize in this action. Doses of relaxin and progesterone which independently are ineffective, together inhibit myometrial contraction amplitude. Relaxin and progesterone are both products of the corpus luteum, a structure necessary for early pregnancy maintenance. The synergistic action of relaxin and progesterone in vitro suggests a similar in vivo physiologic effect in establishing uterine quiescence.     

Serelaxin for the treatment of heart failure

Outcomes for patients with acute heart failure remain suboptimal and treatments principally target improvement of symptoms. To date there has been no therapy approved for acute heart failure shown to improve mortality or readmission risk post-discharge. Serelaxin, a recombinant form of the naturally occurring polypeptide hormone relaxin, has demonstrated promise in preclinical and early clinical trials as a potentially novel therapy for acute heart failure. It is postulated through its anti-fibrotic and vasodilatory effects that this agent can improve outcomes in both the short and long term in these patients. Randomized clinical data has suggested that the medication is safe and well tolerated. However, definitive outcomes data is currently being assessed in a large multi-center trial.     

Stable serum levels of relaxin throughout the menstrual cycle: a preliminary comparison of women with premenstrual dysphoria and controls

Summary Serum levels of relaxin in 25 women with premenstrual dysphoria and 25 age-matched controls were determined at three time points during the menstrual cycle. At the same time, levels of estradiol, progesterone, 17-β-OH-progesterone, free testosterone, total testosterone, sex hormone binding hormone, androstenedione, dehydroepiandrosterone sulphate, and 3-α-androstanediol glucuronide were determined. Detectable levels of relaxin were found in all women in both the follicular and luteal phase as well as around ovulation, the inter-individual variations being larger than intra-individual differences. The levels of relaxin were not influenced by the fluctuation of the other reproductive hormones. A significant difference between the two groups of women was observed, subjects with premenstrual dysphoria displaying reduced levels of relaxin (p < 0.05) compared to controls. Also, when analysed with respect to a variable number of tandem repeats polymorphism (CT repeats followed by GT repeats) in the promotor region of the relaxin H2 gene, women with premenstrual dysphoria (n = 29) were found to display significantly longer GT repeats than controls (n = 35).     

Active Immunization with Relaxin Does Not Influence Objectively Determined Sperm Motility Characteristics in Rabbits: Aktive Immunisierung mit Relaxin beeinflußt objektiv nicht die Speirnatozoen-Motilitäts-Charakteristika bei Kaninchen

Two groups of 5 rabbits were actively immunized with porcine relaxin or sham immunized. Serial analysis of sperm motion characteristics using the computer assisted Hamilton-Thorn Motility Analyzer over a period of 22 weeks did not reveal any significant antibody titers in serum and seminal plasma. In consideration of the present findings and after critical review of the literature it is concluded that an influence of relaxin on sperm motility is unlikely.     

Relaxin promotes differentiation of human breast cancer cells MCF-7 transplanted into nude mice

Previous studies showed that the hormone relaxin acts on human breast cancer MCF-7 cells in vitro by modulating cell proliferation and promoting cell differentiation toward a duct epithelial phenotype. The present study was designed to investigate whether relaxin retains these properties when acting in vivo on MCF-7 cell tumors developed in athymic nude mice. Mice bearing MCF-7 cell tumors transplanted under the mammary fat pad and estrogenized to sustain tumor growth were treated systemically with relaxin (10 μg/day) for 19 days. Vehicle-treated mice were used as controls. Thirty days later, the mice were sacrificed and tumor fragments were analyzed by light and electron microscopy and immunocytochemistry. Measurements of tumor volume were recorded weekly for the overall experimental period. The results obtained indicate that relaxin treatment promotes differentiation of tumor cells towards both myoepithelial-like and epithelial-like cells, as judged by the ultrastructural features of the cells and by the increased expression of smooth muscle actin and cadherins. Measurements of tumor size and of the number of cycling cells show that relaxin, at the doses and times of exposure used in this study, does not significantly influence tumor growth and cell proliferation. Received: 3 March 1999 / Accepted: 28 May 1999     

血清松弛素水平与子痫前期的关系

目的:测定子痫前期患者与正常晚期妊娠孕妇血清中松弛素的水平,探讨松弛素在子痫前期发病过程中的作用。方法:选取15例子痫前期轻度患者、25例子痫前期重度患者作为病例组,20例正常孕妇作为对照组,采用ELISA法对3组血清松弛素浓度进行测定。结果:子痫前期轻度组、子痫前期重度组与正常妊娠组比较血清松弛素水平差异有统计学意义(P0.01),子痫前期轻度组与子痫前期重度组比较血清松弛素水平差异不具有统计学意义(P0.05)。血清松弛素水平与患者血压之间呈显著负相关关系(P0.01)。结论:子痫前期患者血清松弛素水平较正常孕妇明显降低,患者血压水平越高,血清松弛素水平降低越明显,提示松弛素可能是导致子痫前期发病的重要因素之一,与病情密切相关。