Tibolone对去势裸鼠人子宫内膜癌皮下移植瘤生长及转移的影响

目的研究Tibolone对去势裸鼠人子宫内膜癌皮下移植瘤生长及转移的影响,探讨Tibolone治疗子宫内膜癌的安全性.方法建立去势裸鼠人子宫内膜癌皮下移植瘤模型,比较Tibolone灌胃组和对照组给药前后肿瘤体积变化和转移状况.结果Tibolone灌胃组和安慰剂组裸鼠子宫内膜癌皮下移植瘤体积增加值相同(1.976±1.350)mm3和(2.217±1.071)mm3,P=0.879;Tibolone灌胃组(35 d)后,没有引起肿瘤转移.

Tibolone modulates neuronal plasticity through regulating Tau, GSK3β/Akt/PI3K pathway and CDK5 p35/p25 complexes in the hippocampus of aged male mice

Aging is a key risk factor for cognitive decline and age-related neurodegenerative disorders. Also, an age-related decrease in sex steroid hormones may have a negative impact on the formation of neurofibrillary tangles （NFTs）; these hormones can regulate Tau phosphorylation and the principal kinase GSK3β involved in this process. Hormone replacement therapy decreases NFTs, but it increases the risk of some types of cancer. However, other synthetic hormones such as tibolone （TIB） have been used for hormone replacement therapy. The aim of this work was to evaluate the long-term effects of TIB （0.01 mg/kg and 1mg/kg, intragastrically for 12 weeks） on the content of total and hyperphosphorylated Tau （PHF-1） proteins and the regulation of GSK3β/Akt/PI3K pathway and CDK5/p35/p25 complexes in the hippocampus of aged male mice. We observed that the content of PHF-1 decreased with TIB administration. In contrast, no changes were observed in the active form of GSK3β or PI3K. TIB decreased the expression of the total and phosphorylated form of Akt while increased that of p110 and p85. The content of CDK5 was differentially modified with TIB： it was increased at low doses and decreased at high doses. When we analyzed the content of CDK5 activators, an increase was found on p35; however, the content of p25 decreased with administration of low dose of TIB. Our results suggest a possible mechanism of action of TIB in the hippocampus of aged male mice. Through the regulation of Tau and GSK3β/Akt/PI3K pathway, and CDK5/p35/p25 complexes, TIB may modulate neuronal plasticity and regulate learning and memory processes.

Application of UPLC-MS/MS for separation and quantification of 3α-Hydroxy Tibolone and comparative bioavailability of two Tibolone formulations in healthy volunteers

A novel, fast, sensitive and robust method based on ultra-performance liquid chromatography coupled to atmospheric pressure electrospray ionization tandem mass spectrometry （UPLC-ESI-MS/MS） has been developed to separate two Tibolone stereoisomers i.e., 3α-Hydroxy Tibolone and 3β-Hydroxy Tibolone and to quantify 3α-Hydroxy Tibolone using p-toulenesulfonyl isocyanate （PTSI） as a derivatizing reagent in human plasma. 3α-Hydroxy Tibolone-13CD3 was used as an internal standard （IS）. The analyte and IS were extracted from human plasma by liquid-liquid extraction using ethyl acetate. Extracted samples were analyzed by UPLC-ESI-MS/MS. Chromatography was performed using binary gradient on UPLC analytical column. A linear calibration curve over the range of 0.100-35.000 ng/ mL was obtained and lower limit of quantification （LLOQ） was 0.100 ng/mL demonstrating acceptable accuracy and precision. This method was successfully applied to a pharmacokinetic study in order to compare a test Tibolone 2.5 mg formulation vs. a reference 2.5 mg Tibolone tablet formulation in 50 post-menopausal/surgical menopause female human volunteers under fasting conditions. It is concluded that test formulation of Tibolone is bioequivalent to reference formulation of Tibolone.

Low dose and short-term therapy of tibolone reduces the cardiovascular disease risk in postmenopausal women

Objective:To investigate the effects of low dose tibolone short-term therapy on clinic, endocrine and markers of cardiovascular disease in healthy postmenopausal women.Methods: A prospective study involved a total of 42 eligible postmenopausal women. 22 cases as group A and 20 cases as group B. Complete baseline work-up including Kupperman score,body mass index (BMI), gonadotropin (FSH, LH), estrogen (E2), testosterone (T), sex hormone binding globulin (SHBG), plasminogen activator inhibitor type 1 (PAI-1), tissue plasminogen activator (tPA), high-sensitivity C-response protein (hs-CRP), nitrogen oxide (NO)and fasting lipid, glucose(FPG), insulin(FINS) were performed in all subjects. Postmenopausal women in group A were treated with 1.25 mg tibolone daily. Women in group B were treated with 0. 625 mg tibolone daily. Women both in group A and group B were given calcium 600 mg with vitamin D 125IU per day. At the end of the 12-weeks therapy, subjects were re-evaluated and above parameters were measured.Results:No significant differences between group A and group B were found at baseline.Twenty-eight cases (fourteen cases in each group) completed the study. Kupperman score decreased from (22.1±8.0) and (25.4±7.5) to (7.7±4.5) and (5.2±4.5) and plasminogen activator inhibitor type 1 decreased from (95.8±32.4)μg/L and (102.9±42.6)μg/L to (72.2±39.6)μg/L and (79.9±30. 1) μg/L significantly in group A and group B respectively after treatment. In group A, Blood pressure decreased significantly from (120 ± 10)/(83 ± 6) mmHg to (110±14)/(77± 9) mmHg (P＜0.05), testosterone increased significantly from (0. 6 ±0. 4)nmol/L to (1.3 ± 1.1) nmol/L (P＜0. 05), free testosterone increased from (0. 001 ±0. 002)nmol/L to (0. 003±0. 003) nmol/L significantly (P＜0.01), SHBG decreased from (7.6±4. 9)nmol/L to (4. 3±2.9) nmol/L significantly (P＜0.05), total cholesterol decreased from (5.4±0. 8) mmol/L to (5.0±0.8) mmol/L significantly (P＜0.01), ApoA decreased from (1.8±0.3)mg/dl to (1.7±0. 3) mg/dl significantly (P＜0.05), fasting glucose decreased from (5. 6±0.8)mmol/L to (3.9±1.1) mmol/L significantly (P＜0.01) and no significant differences in BMI,FSH, LH, E2, tPA, hs-CRP, NO, TG, HDL-C, LDL-C, apoB were found after treatment. In group B, there were no significant differences in other parameters found after treatment except Kupperman score and PAI-1.Conclusions: 1.25 mg/d tibolone short-term therapy was associated with improved fibrinolytic factors and decreased Kupperman score, blood pressure, total cholesterol and fasting blood glucose level. 0. 625 mg/d tibolone therapy resulted in decrease Kupperman score and improvement of fibrinolytic factors. These changes relieve climacteric symptoms and may have some benefits on preventing the development of cardiovascular disease. An increased testosterone and free testosterone levels in 1.25 mg dose of tibolone therapy may increase energy level, general wellbeing and sexual desire in postmenopausal women. Low dose tibolone replacement therapy is a convenient effective HRT for postmenopausal

Effect of tibolone pretreatment on kinases and phosphatases that regulate the expression and phosphorylation of Tau in the hippocampus of rats exposed to ozone

Oxidative stress （OS） is a key process in the development of many neurodegenerative diseases, memory disorders, and other pathological processes related to aging. Tibolone （TIB）, a synthetic hormone used as a treatment for menopausal ymptoms, decreases lipoperoxidation levels, prevents memory impairment and learning disability caused by ozone （O3） exposure. However, it is not clear if TIB could prevent the increase in phosphorylation induced by oxidative stress of the microtubule-associated protein Tau. In this study, the effects of TIB at different times of administration on the phosphorylation of Tau, the activation of glycogen synthase kinase-3β （GSK3β）, and the inactivation of Akt and phosphatases PP2A and PTEN induced by O3 exposure were assessed in adult male Wistar rats. Rats were divided into 10 groups： control group （ozone-free air plus vehicle [C]）, control ＋ TIB group （ozone-free air plus TIB 1 mg/kg [C ＋ TIB]）; 7,15, 30, and 60 days of ozone exposure groups [O3] and 7, 15, 30, and 60 days of TIB 1 mg/kg before ozone exposure groups [O3 ＋ TIB]. The effects of O3 exposure and TIB administration were assessed by western blot analysis of total and phosphorylated Tau, GSK3β, Akt, PP2A, and PTEN proteins and oxidative stress marker nitrotyrosine, and superoxide dismutase activity and lipid peroxidation of malondialdehyde by two different spectrophotometric methods （Marklund and TBARS, respectively）. We observed that O3 exposure increases Tau phosphorylation, which is correlated with decreased PP2A and PTEN protein levels, diminished Akt protein levels, and increased GSK3β protein levels in the hippocampus of adult male rats. The effects of O3 exposure were prevented by the long-term treatment （over 15 days） with TIB. Malondialdehyde and nitrotyrosine levels increased from 15 to 60 days of exposure to O3 in comparison to C group, and superoxide dismutase activity decreased. Furthermore, TIB administration limited the changes induced by O3 exposure. Our results suggest a beneficial use of hormone replacement therapy with TIB to prevent neurodegeneration caused by O3 exposure in rats.

Beneficial Effects of Tibolone on Sexual Dys-function in Women with Premature Ovarian Failure (POF)

Introduction: Premature Ovarian Failure (POF) is cessation of ovarian functions before the age of 40 years old with consequent cessation of menstruation. Objective of study: The aim of this study was to evaluate the association between Premature Ovarian Failure and sexual dysfunctions and outcome of management with tibolone. Patients and Methods: Thirty-one women with Premature Ovarian Failure seen at the outpatient clinic of Maternity Hospital were enrolled into the study with 31 healthy women as control group. The instrument of data collection included two types of questionnaires to assess the effect of Premature Ovarian Failure on sexuality. All the women with POF had oral tibolone 2.5 mg for at least one year and the second questionnaire and the profiles were repeated. Results: Of the 31 women with POF that presented with sexual dysfunction (SD), 27 (87.1%) complained of one or more SD domains such as reduced frequency of coitus, dyspareunia, vaginal dryness, reduced libido and general sexual satisfaction (P < 0.01), amenorrhea (P < 0.01) and hot flashes compared to 5 (16.1%) control women (P < 0.01). Administration of tibolone was associated with significant increase in frequency of coitus, reduced dyspareunia and vaginal dryness, increase libido and general satisfaction and happiness. Reduction of sexual dysfunction was predicated on the estrogenic, progestogenic and androgenic metabolite of tibolone through the reduction of serum level of FSH and LH and increased levels of estrogen and testosterone (P < 0.01). Tibolone had no adverse effect on serum lipid profile. Conclusion: Premature Ovarian Failure is associated with sexual dysfunction. Tibolone provides an effective means of treating sexual dysfunction caused by Premature Ovarian Failure.

Tibolone Reverses NAFLD in Ovariectomised Rats by Reducing Adiposity and Insulin Resistance

This study aimed to investigate the effects of tibolone,a synthetic steroid,on several metabolic dysfunctions induced by oestrogen deficiency,in rats.Ovariectomised(OVX)rats were used as animal model of postmenopausal metabolic syndrome.The OVX rats were treated with daily doses of tibolone(0.16 mg/kg)and the results were compared with control(sham-operated)and OVX untreated rats.Tibolone reduced the adiposity and the visceral adipocyte size in OVX rats.The insulin sensitivity was also improved,and a decrease in the activity of the adipose tissue hormone-sensitive lipase enzyme was recorded.The lower lipolysis by visceral adipocytes,associated with the recovery of peroxisomalβ-oxidation by tibolone may have contributed to the reversion of NAFLD in treated OVX rats.The reduction of liver lipid contents resulted in a general improvement in the liver redox state.In addition,tibolone reduced the mitochondrial ROS generation and restored the activity of glucose-6-phosphate dehydrogenase.Tibolone also exerted antioxidant effects on inguinal adipose tissue.Tibolone exerted several beneficial effects on cellular and metabolic dysfunctions induced by ovariectomy in rats.One important mode of action of tibolone was the reduction of the visceral adipocyte size,corroborating the relationship between this one and the development and progression of several comorbidities associated with metabolic syndrome.

Effect of tibolone as well as Estradiol and Drospirenone replacement therapy on the neurohumoral indexes and immune function in perimenopausal women

Objective: To explore the effect of tibolone as well as Estradiol and Drospirenone replacement therapy on the neurohumoral indexes and immune function in perimenopausal women. Methods: A total of 180 perimenopausal women who were treated in our hospital between December 2014 and December 2016 were collected and divided into the tibolone group (n=90) as well as Estradiol and Drospirenone group (n=90) by random number table, they received tibolone as well as Estradiol and Drospirenone replacement therapy respectively, and both therapies lasted for 6 months. The differences in serum levels of neurohumoral indexes and immune function indexes were compared between the two groups. Results:Before treatment, differences in serum levels of neurohumoral indexes and immune function indexes were not statistically significant between the two groups. After 6 months of treatment, serum E2, IL-4 and IL-13 levels of both groups of patients were significantly higher than those before treatment while P, T, FSH, LH, PRL, IFN-γ and IL-2 levels were significantly lower than those before treatment, and serum E2, IL-4 and IL-13 levels of observation group were significantly higher than those of control group while P, T, FSH, LH, PRL, IFN-γ and IL-2 levels were significantly lower than those of control group. Conclusion: Both tibolone and Estradiol and Drospirenone can be used in the treatment of women with perimenopausal syndrome, but tibolone is more effective in optimizing hormone levels and equalizing immune function.

Efficacy and Safety Investigation of Kuntai Capsule for the Add-back Therapy of Gonadotropin Releasing Hormone Agonist Administration to Endometriosis Patients： A Randomized,Double-blind, Blank-and Tibolone-controlled Study

Background：As a Chinese Traditional Medicine product,Kuntai capsule could improve the peri-menopausal symptoms in postmenopausal women.But it is still not clear whether Kuntai capsule has a good effect on alleviating peri-menopausal symptoms induced by gonadotropin releasing hormone agonist （GnRH-a） treatment.The purpose of this study was to investigate the clinical effectiveness and safety of Kuntai capsule,on peri-menopausal symptoms in endometriosis （EMS） patients,with postoperative GnRH-a treatment.Methods：Ninety EMS ovarian cyst women with postoperative GnRH-a administration were enrolled in the study,and were randomly divided into Kuntai group,Tibolone group,or blank Control group.The therapeutic strategy in Kuntai group was 4 Kuntai capsules tid,po for 12 weeks after the first GnRH-a injection,while Tibolone 2.5 mg qd,po for 12 weeks in Tibolone group.There was no drug addition in Control group.Climacteric complaints were evaluated by Kupperman menopausal index （KMI） and hot flash/sweating score.Liver and renal functions,lipid profile,serum sex hormone levels and endometrial thickness were measured,and the frequency of adverse events in Kuntai and Tibolone groups was recorded.Results：（l） Before GnRH-a therapy,the baseline parameter results were comparable in the three groups （P ＞ 0.05）.（2） After GnRH-a therapy,KMI and hot flash/sweating scores in all the three groups increased significantly （P ＜ 0.05）.At the 4th week after GnRH-a therapy,KMI and hot flash/sweating score results were as follows：Control group ＞ Kuntai group ＞ Tibolone group （P ＜ 0.05）; at the 8th and 12th week after GnRH-a therapy,KMI and hot flash/sweating score in Control group were significantly higher than the other two groups （P ＜ 0.05）,and no significant difference was identified between Kuntai and Tibolone group （P ＞ 0.05）.（3） No statistical change took place in the liver and renal functions and lipid profile in all the three groups after the treatment （P ＞ 0.05）.（4） The posttherapeutic serum follicle-stimulating hormone （FSH）,luteinizing hormone （LH） and estradiol （E2） level and endometrial thickness decreased significantly in all the three groups （P ＜ 0.05）.After therapy,serum E2 level in Tibolone group was obviously higher than the other two groups （P ＜ 0.05）,while FSH and LH levels were obviously lower （P ＜ 0.05）.（5） The incidence of vaginal bleeding,breast distending pain in Tibolne group was obviously higher than Kuntai group （P ＜ 0.05）.Conclusions：Kuntai capsule is effective on the peri-menopausal symptoms induced by postoperative GnRH-a administration to EMS patients,although its clinical effect might be a few weeks later than Tibolone.Kuntai capsule might be a little safer than Tibolone tablet.

Effects of estrogen and tibolone on bladder histology and estrogen receptors in rats

Background Estrogen deficiency causes atrophic changes within the urogenital tract, and is associated with urinary symptoms. The purpose of this study was to investigate the effects of estrogen and tibolone on bladder histology, and the changes of estrogen receptor a and β （ERα and β） protein expression in the detrusor muscle.Methods Forty female rats were separated into four groups of ten each. They received a sham operation （Sham）, ovariectomy （Ovx）, ovariectomy plus estrogen replacement （Ovx＋E）, or ovariectomy plus tibolone treatment （Ovx＋T）. After 12 weeks each rat was anesthetized and the bladders were removed. The bladders＇ ultra structure, collagen fiber （CF） to smooth muscle（SM） ratio and ER subtypes were studied. Statistical analyses were performed using the one-way analysis of variance test. Results Ovx resulted in significant degeneration in bladder ultra structure; however, estrogen and tibolone reversed those changes. Ovx increased the CF/SM ratio, estrogen and tibolone resulted in an increase. Two estrogen receptors （ERs） were expressed in the bladder detrusor, with ERβ the main subtype. Ovx resulted in up-regulation of ERα and down-regulation of ERβ. With estrogen and tibolone treatment, ERβ showed a significant increase but ERα showed no significant difference compared with Ovx. Conclusions Estrogen deficiency deteriorates bladder ultra structure and histology. Supplementary estrogen can improve bladder function which may be due to inhibition of collagen hyperplasia and increased SM density. ERβ has an important role in mediating estrogen function in the bladder. Tibolone has a mild estrogenic action and has an effect on bladder function and structure to some degree.

Dynamic monitoring of menopause hormone therapy and defining the cut-off value of endometrial thickness during uterine bleeding

The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uterine bleeding. We followed 619 postmenopausal women, aged 40-60 years, for two years. There were 301 subjects in the low-dose tibolone treatment group and 318 subjects in the control group. The ovarian area, uterine volume and endometrial thickness in all participants were measured by transvaginal ultrasound prior to, one and two years post enrollment, respectively. Endometrial specimens were collected from all subjects with abnormal uterine bleeding during the follow-up period. We found that the uterine volume in the treatment group was greater than that in the control group, and the difference was significant （P〈0.05）, but there were no significant differences in ovarian area and endometrial thickness between the two groups （P〉0.05）. When the cut-off value for endometrial thickness was 7.35 ram, the sensitivity and specificity were 100% and 79.07%, respectively, and 85.71% and 93.02% when 7.55 mm was set as the cut-offduring tibolone therapy. The results indicate that low-dose tibolone therapy may postpone uterine atrophy and the cut-off value of endometrial thickness may be appropriately adjusted for curettage.

Effects of estrogen receptor modulators on cytoskeletal proteins in the central nervous system

Estrogen receptor modulators are compounds of interest because of their estrogenic agonistic/antagonistic effects and tissue specificity. These compounds have many clinical applications, particularly for breast cancer treatment and osteoporosis in postmenopausal women, as well as for the treatment of climacteric symptoms. Similar to estrogens, neuroprotective effects of estrogen receptor modulators have been described in different models. However, the mechanisms of action of these compounds in the central nervous system have not been fully described. We conducted a systematic search to investigate the effects of estrogen receptor modulators in the central nervous system, focusing on the modulation of cytoskeletal proteins. We found that raloxifene, tamoxifen, and tibolone modulate some cytoskeletal proteins such as tau, microtuble-associated protein 1（MAP1）, MAP2, neurofilament 38（NF38） by different mechanisms of action and at different levels： neuronal microfilaments, intermediate filaments, and microtubule-associated proteins. Finally, we emphasize the importance of the study of these compounds in the treatment of neurodegenerative diseases since they present the benefits of estrogens without their side effects.

Symptomatic changes in postmenopause with different methods of hormonal therapy

Objective: The diversity of opinions on the adverse effects of medications used to treat postmenopausal symptoms has prompted the use of various routes and mechanisms of action that need to be explored because bioavailability of the medications can vary. In order to select the appropriate route of administration for hormonal therapy (HT), it is necessary to determine baseline therapeutic efficacy. Design: We designed a prospective, randomized study consisting of four groups of postmenopausal wo-men: group 1 received oral conjugated estrogens, group 2 received a synthethic steroid, group 3 received estradiol nasally in spray form, and group 4 used transdermal estradiol in the form of patches. Criteria used to evaluate effectiveness was the Greene scale, which evaluate six components. These criteria were applied to each patient before hormonal intervention and then each month for 6 months. Luteinizing hormone (LH), follicle stimulating horone (FSH) and estradiol concentration were determined by chemiluminescence. Student’s t-test was used for intra-group comparisons before and after treatment. Results: There was a significant decrease in the vasomotor and sexual component (p < 0.05) with the use of four HT types. For depression, a difference was observed with synthetic steroids and oral estrogens. Upon analyzing the somatic component there was a decrease in symptoms with nasal and transdermal routes. Psychological changes were observed with the use of oral synthethic steroids and transdermal patches. Anxiety component demonstrated differences with nasal spray and oral estrogens, although all HT forms in this component showed a pattern of irregular changes. Conclusions: Changes in the response could be due each route of administration and medication used. Absorption variability may exist, which has repercussions in the control of symptoms and should be taken into consideration when selecting the appropriate route of administration for patients beginning HT.