Progesterone receptor expression in human saphenous veins

High risk oral contraceptive hormones do not directly enhance endothelial cell procoagulant activity in vitro

BACKGROUND

Oral contraceptive (OC) use increases venous thromboembolism risk 2-5-fold. Procoagulant changes can be detected in plasma from OC users even without thrombosis, but cellular mechanisms that provoke thrombosis have not been identified. Endothelial cell (EC) dysfunction is thought to initiate venous thromboembolism. It is unknown whether OC hormones provoke aberrant procoagulant activity in ECs.

OBJECTIVE

Characterize the effect of high-risk OC hormones (ethinyl estradiol [EE] and drospirenone) on EC procoagulant activity and the potential interplay with nuclear estrogen receptors ERα and ERβ and inflammatory processes.

METHODS

Human umbilical vein and dermal microvascular ECs (HUVEC and HDMVEC, respectively) were treated with EE and/or drospirenone. Genes encoding the estrogen receptors ERα and ERβ (ESR1 and ESR2, respectively) were overexpressed in HUVEC and HDMVEC via lentiviral vectors. EC gene expression was assessed by RT-qPCR. The ability of ECs to support thrombin generation and fibrin formation was measured by calibrated automated thrombography and spectrophotometry, respectively.

RESULTS

Neither EE nor drospirenone, alone or together, changed expression of genes encoding anti- or procoagulant proteins (TFPI, THBD, F3), integrins (ITGAV, ITGB3), or fibrinolytic mediators (SERPINE1, PLAT). EE and/or drospirenone did not increase EC-supported thrombin generation or fibrin formation, either. Our analyses indicated a subset of individuals express ESR1 and ESR2 transcripts in human aortic ECs. However, overexpression of ESR1 and/or ESR2 in HUVEC and HDMVEC did not facilitate the ability of OC-treated ECs to support procoagulant activity, even in the presence of a pro-inflammatory stimulus.

CONCLUSIONS

The OC hormones EE and drospirenone do not directly enhance thrombin generation potential of primary ECs in vitro.

Seasonal variation in swelling of lower extremity edema in patients with chronic venous insufficiency

OBJECTIVE

We had observed that some patients with chronic venous insufficiency (CVI) had reported their lower extremity edema was worse during warmer weather. Limited research is available regarding the seasonal variation in lower extremity edema. Patients with CVI were questioned to determine whether they had experienced significant seasonal variation in their lower extremity edema and which factors might be associated with such variation.

METHODS

Consecutive patients with lower extremity edema were asked whether the edema was worse in the summer or warmer weather. Data was collected between June 2017 and August 2020. A total of 1683 patients (age range, 16-102 years; mean ± standard deviation, 62 ± 14.3 years). Of the 1683 patients, 1157 were female (mean age, 62 ± 14.13 years) and 526 were male (mean age, 62.5 ± 13.82 years). Data were also collected on the presenting symptoms, degree of venous reflux of the great saphenous vein (GSV) reported from the most recent duplex ultrasound, and the season at the time of questioning. For statistical analysis, χ² goodness-of-fit tests and one-way analysis of variance tests were used.

RESULTS

Of the 1683 patients, 56.6% had reported worsening of their lower extremity edema during warmer weather, including 62.7% of the female patients and 37.3% of the male patients. The female patients had reported significantly more worsening of their lower extremity edema (P = 7.06e-18). Female patient age was associated with whether they had experienced worsening (P = .02), with more younger patients reporting worsening. Male patient age was not associated with whether they had reported worsening (P = .97). No significant differences were found in the degree of presenting symptoms between those who had and had not reported worsening (P = .58). Also, no significant differences were found in the degree of venous reflux between the right (P = .61) and left (P = .89) GSV between those who had and had not reported worsening. The season in which the patients had presented during the study period was associated with whether they had reported worsening edema. The patients who had been questioned in the winter (December, January, February) and summer (June, July, August) had reported more worsening of their edema in the warmer months (P = .008 and P = .0002, respectively). The patients who had been questioned in the spring (March, April, May) and fall (September, October, November) had not reported significantly more worsening of their edema in the warmer months (P = .167 and P = .119, respectively).

CONCLUSIONS

Of the 1683 patients surveyed, 56.6% had reported worsened edema in the warmer weather. The women (especially the younger women) in the present study had experienced significant worsening, although the men had not. The degree of GSV venous reflux and severity of the presenting symptoms of the patients was not associated with whether worse edema had been reported. However, the season in which the patients had been questioned was associated with the report of worsening edema. The patients questioned in the coldest and warmest months had reported significantly more worsening. The patients questioned in the milder months had not reported significantly more worsening. These findings suggest that a sex and age bias exists in the seasonal variation of lower extremity edema in patients with CVI.

GPR30 Promotes the Phenotypic Switching of Vascular Smooth Muscle Cells via Activating the AKT and ERK Pathways

Background

Lower extremity varicose veins (LEVVs) are a common venous disorder of venous dilation and tortuosity. The functional integrity of vascular smooth muscle cells (VSMCs), the majority of the cells in venous tissues, and their phenotypic differences play important roles in the occurrence and development of LEVV. However, the underlying mechanism remains unclear.

Methods

The expression of estrogen receptors ERα and ERβ and G-protein-coupled receptor 30 (GPR30) in LEVV tissues and the role of GPR30 in VSMC phenotypic switching were examined by Western blotting and quantitative real-time PCR. Finally, the related mechanisms underlying LEVVs were explored by Western blotting.

Results

The serum estradiol content was increased in LEVV patients compared with normal control patients, but the mRNA levels of ERα and ERβ were not significantly different. GPR30 was overexpressed in LEVVs, and high expression of GPR30 promoted the maintenance of a synthetic phenotype in which OPN, MMP-1 and MMP-9 were highly expressed and α-SMA was poorly expressed in VSMCs. Finally, the mechanism by which GPR30 promotes the phenotypic switching of VSMCs is dependent on the ERK1/2 and AKT pathways.

Conclusion

GPR30 may contribute to the pathogenesis of LEVVs by promoting the maintenance of a synthetic phenotype in VSMCs by activating the ERK1/2 and AKT pathways, and GPR30 might be a novel therapeutic target for clinical LEVV treatment.

Increase and Redistribution of Sex Hormone Receptors in Premenopausal Women Are Associated with Varicose Vein Remodelling

In chronic venous insufficiency of the lower limbs, data show that the clinical manifestation is varicose veins (VVs), and VV epidemiology suggests that sex hormones directly influence disease development through intracellular receptors. This study aimed to determine the presence and localization of oestrogen receptors (ERs), progesterone receptors (PRs), and androgen receptors (ARs) in both healthy and VV wall cells and their relationship with gender. In this study, samples from patients without a history of venous disease (CV) (n = 18) and with VV (n = 40) were used. The samples were divided by gender: CV women (CVw) = 6, CV men (CVm) = 12, VV women (VVw) = 25, and VV men (VVm) = 15. RT-qPCR and immunohistochemical techniques were performed, and increased ER and PR protein expression was found in VVw in all tunica layers. ARs were localized to the adventitial layer in the CV and were found in the neointima in VVs. mRNA expression was increased for ER and PR in VVw. AR gene expression was significantly decreased in VVm. The increase in the number of these receptors and their redistribution through the wall reinforces the role of sex hormones in varicose vein development.

Endocrine mechanisms in the pathogenesis of primary varicosis

Introduction: Varicose veins affect up to 40 % of men and up to 51 % of women. The patho-physiology of primary varicosis (chronic venous insufficiency, CVI) is poorly understood. Here, the available data on possible endocrine mechanisms in healthy and varicose veins are reviewed.

Methods: An extensive literature search was conducted in PubMed using the following key words: Chronic venous insufficiency, CVI, chronic venous disease, CVD, varicosis, saphenous vein, pathogenesis, hormone.

Results: Several theories ranging from incompetence of the valves to functional, biological or morphologic changes in different layers of the vein wall have been proposed. However, an increasing body of evidence suggests that endocrine mechanisms might be involved in the pathogenesis of primary varicosis. In this respect a growing number of hormones (e.g. estrogen, progesterone, relaxin-2, and oxytocin) and their receptors have been linked to primary varicosis in experimental, pharmacological and histological studies.

Conclusion: In summary, endocrine-based mechanisms seem to play a role in the pathogenesis of primary varicosis. This opens up the perspective for pharmacological treatments targeting the various described endocrine regulatory networks.

Influence of Dexamethasone on Some Reproductive Hormones and Uterine Progesterone Receptor Localization in Pregnant Yankasa Sheep in Semiarid Zones of Nigeria

Dexamethasone is widely used in both veterinary and human medical practices. However, it seems to cause some deleterious effects on pregnancy probably by causing changes in the reproductive hormone levels and their corresponding receptor concentrations. This study investigated the effects of dexamethasone on these parameters. Twenty healthy adult Yankasa sheep comprising 18 ewes and 2 rams were used for this study. Pregnancies were achieved by natural mating after estrus synchronization. Dexamethasone was administered at 0.25 mg/kg body weight on days 1, 3, and 5 during first trimester; days 51, 53, and 55 during second trimester; and days 101, 103, and 105 during the third trimester. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested through caesarean section for immunohistochemical analysis. Results showed that dexamethasone significantly (p < 0.05) decreased progesterone concentrations and caused abortion in Yankasa sheep but had no significant (p > 0.05) effect on estrogen, while progesterone receptors (PR) were upregulated. The abortion could probably be due to decreased progesterone concentrations as a consequence of the adverse effects on placenta. The PR upregulation may be a compensatory mechanism to increase progesterone sensitivity. It was concluded that dexamethasone should not be used in advanced pregnancy in Yankasa sheep.

Effects of dexamethasone on progesterone and estrogen profiles and uterine progesterone receptor localization during pregnancy in Sahel goat in Semi-Arid region

BACKGROUND

Despite the widespread use of dexamethasone in veterinary and human medicine, it is reported to cause some severe pregnancy related side effects like abortion in some animals. The mechanism of the response is not clear but seems to be related to interspecies and/or breed difference in response which may involve alterations in the concentrations of some reproductive hormones.

METHODS

Twenty Sahel goats comprising 18 does and 2 bucks were used for this study. Pregnancies were achieved by natural mating after synchronization. Repeated dexamethasone injections were given at 0.25 mg/kg body weight. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested at days 28 and day 78 of gestation through caesarean section for immunohistochemical analysis using 3 pregnant does randomly selected from each group at each instant. Data were expressed as Means ± Standard Deviations and analyzed using statistical soft ware package, GraphPad Instant, version 3.0 (2003) and progesterone receptor (PR) were scored semi-quantitatively.

RESULTS

Dexamethasone treatments had no significant (p > 0.05) effect on progesterone and estrogen concentrations in pregnant Sahel goats but up regulated PR from 2+ to 3+ in second trimester.

CONCLUSION

As dexamethasone adverse effect on placenta is an established fact, the lack of effect on progesterone level in this study may be due to the fact that unlike other species whose progesterone production during pregnancy is placenta - dependent, in goats is corpus luteum - dependent. Consequently dexamethasone adverse effect on placenta reported in literatures did not influence progesterone levels during pregnancy in Sahel goat. The up regulation of progesterone receptor (PR) in Sahel goat gravid uterus is a beneficial effects and that dexamethasone can safely be used in corpus luteum - dependent progesterone secreting pregnant animal species like Sahel goat and camel. Therefore source of progesterone secretions during pregnancy should be considered in clinical application of dexamethasone in pregnancy.

Duplex ultrasonography findings are not related to menstrual cycle phases in women with early symptoms of lower extremity chronic venous disease

PURPOSE

To investigate if duplex ultrasonography findings change according to the menstrual cycle phases in women with early symptoms of lower extremity chronic venous disease.

METHODS

Thirty women (60 extremities) aged 18-50 years with regular menstrual cycles who presented with complaints of telangiectasia and/or trunk varices with accompanying leg pain were evaluated prospectively by duplex ultrasonography at three different times of a single menstrual cycle. Previous DVT or menstrual irregularities were exclusion criteria. All exams were performed by the same radiologist, under the same conditions. Reflux was provoked in the deep veins, great saphenous vein (GSV), and small saphenous vein (SSV) using the Valsalva maneuver. Reflux times in each vein and average diameters of the GSV and SSV were recorded.

RESULTS

Reflux times showed no significant differences in any of the vein segments and the diameters of GSV and SSV were similar in the different menstrual phases (p > 0.05). Reflux was not predominant at any specific phase, and its presence was independent of menstrual phase.

CONCLUSIONS

Reflux was not specific to a particular phase of menstrual cycle in women with early symptoms of chronic venous disease.

Age at menopause, reproductive history, and venous thromboembolism risk among postmenopausal women: the Women's Health Initiative Hormone Therapy clinical trials

OBJECTIVE

This study aims to investigate venous thromboembolism (VTE) risk in relation to age at menopause, age at menarche, parity, bilateral oophorectomy, and time since menopause, as well as any interaction with randomized hormone therapy (HT) assignment, among postmenopausal women.

METHODS

Using pooled data from the Women's Health Initiative HT clinical trials including 27,035 postmenopausal women aged 50 to 79 years who had no history of VTE, we assessed the risk of VTE in relation to age at menopause, age at menarche, parity, bilateral oophorectomy, and time since menopause by Cox proportional hazards models. Linear trends, quadratic relationships, and interactions of reproductive life characteristics with HT on VTE risk were systematically tested.

RESULTS

During follow-up, 426 women reported a first VTE, including 294 non-procedure-related events. No apparent interaction of reproductive life characteristics with HT assignment on VTE risk was detected, and there was not a significant association between VTE and age at menarche, age at menopause, parity, oophorectomy, or time since menopause. However, analyses restricted to non-procedure-related VTE showed a U-shaped relationship between age at menopause and thrombotic risk that persisted after multivariable analysis (P < 0.01). Compared with women aged 40 to 49 years at menopause, those who had early menopause (age <40 y) or late menopause (age >55 y) had a significantly increased VTE risk (hazard ratio [95% CI]: 1.8 [1.2-2.7] and 1.5 [1.0-2.4], respectively).

CONCLUSIONS

Reproductive life characteristics have little association with VTE and do not seem to influence the effect of HT on thrombotic risk among postmenopausal women. Nevertheless, early and late onset of menopause might be newly identified risk factors for non-procedure-related VTE.

Progesterone receptor in the vascular endothelium triggers physiological uterine permeability preimplantation

Vascular permeability is frequently associated with inflammation and is triggered by a cohort of secreted permeability factors such as vascular endothelial growth factor (VEGF). Here, we show that the physiological vascular permeability that precedes implantation is directly controlled by progesterone receptor (PR) and is independent of VEGF. Global or endothelial-specific deletion of PR blocks physiological vascular permeability in the uterus, whereas misexpression of PR in the endothelium of other organs results in ectopic vascular leakage. Integration of an endothelial genome-wide transcriptional profile with chromatin immunoprecipitation sequencing revealed that PR induces an NR4A1 (Nur77/TR3)-dependent transcriptional program that broadly regulates vascular permeability in response to progesterone. Silencing of NR4A1 blocks PR-mediated permeability responses, indicating a direct link between PR and NR4A1. This program triggers concurrent suppression of several junctional proteins and leads to an effective, timely, and venous-specific regulation of vascular barrier function that is critical for embryo implantation.

Selective suppression of endothelial cytokine production by progesterone receptor

Steroid hormones are well-recognized suppressors of the inflammatory response, however, their cell- and tissue-specific effects in the regulation of inflammation are far less understood, particularly for the sex-related steroids. To determine the contribution of progesterone in the endothelium, we have characterized and validated an in vitro culture system in which human umbilical vein endothelial cells constitutively express human progesterone receptor (PR). Using next generation RNA-sequencing, we identified a selective group of cytokines that are suppressed by progesterone both under physiological conditions and during pathological activation by lipopolysaccharide. In particular, IL-6, IL-8, CXCL2/3, and CXCL1 were found to be direct targets of PR, as determined by ChIP-sequencing. Regulation of these cytokines by progesterone was also confirmed by bead-based multiplex cytokine assays and quantitative PCR. These findings provide a novel role for PR in the direct regulation of cytokine levels secreted by the endothelium. They also suggest that progesterone-PR signaling in the endothelium directly impacts leukocyte trafficking in PR-expressing tissues.

Steroid-coupled liposomes for targeted delivery to tumor

The steroidal receptors play a key role in protein synthesis and maintain the homeostasis in normal and diseased state, including tumorigenesis at the target tissues when overactivated. Thus steroidal receptors may act as potential targets for selective delivery of different therapeutic agents as they are overexpressed by a number of endocrinal tumors. The selective delivery of these agents may be a better treatment strategy for endocrinal cancer as it may also result in cytosolic and nuclear delivery of cytotoxic agents. In this review, the targeting potential of steroidal receptors for the drug or bioactive(s) delivery is discussed. The ligands that have been proven to be effective for specific steroidal receptors can be used as vectors for carrying the drug or drug-delivery system to the desired site of drug action in an optimum concentration. This strategy will not only minimize the undesired side effects associated with nonspecific delivery of drug, but will also maximize the drug utilization. Ligand-conjugated liposomes as a carrier of bioactives prevent passive diffusion of the encapsulated drug to normal cells, increase the time of circulation and reduce the undesirable side effects of a drug.

Estrogen receptor-mediated enhancement of venous relaxation in female rat: implications in sex-related differences in varicose veins

BACKGROUND

A greater incidence of varicose veins has been reported in premenopausal women than in men. We hypothesized that the sex differences in venous function reflect reduced constriction and enhanced venous dilation in women due to direct venous relaxation effects of estrogen on specific estrogen receptors (ER).

METHODS

Circular segments of inferior vena cava (IVC) from male and female Sprague-Dawley rats were suspended between two wires, and isometric contraction (in mg/mg tissue) to phenylephrine, angiotensin II (AngII), and 96 mM KCl was measured. To investigate sex differences in venous smooth muscle, Ca(2+) release from the intracellular stores, and Ca(2+) entry from the extracellular space, the transient phenylephrine contraction in 0 Ca(2+) Krebs was measured. Extracellular CaCl(2) (0.1, 0.3, 0.6, 1, 2.5 mM) was added, and the [Ca(2+)](e)-dependent contraction was measured. To investigate sex differences in venous endothelial function, acetylcholine-induced relaxation was measured. To test the role of specific ERs, the amount of venous tissue ERs was measured using Western blots, and the venous relaxation in response to 17beta-estradiol (E2, activator of most ERs), 4,4,'4''-(4-propyl-[1H]-pyrazole-1,3,5-triyl)-tris-phenol (PPT; ERalpha agonist), 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN; ERbeta agonist), and ICI 182,780 (ERalpha/ERbeta antagonist, and G protein-coupled receptor 30 [GPR30] agonist) was measured in IVC segments nontreated or treated with the nitric oxide synthase (NOS) inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME).

RESULTS

Phenylephrine caused concentration-dependent contraction that was less in female (max 104.2 +/- 16.2) than male IVC (172.4 +/- 20.4). AngII (10(-6))-induced contraction was also less in female (81.0 +/- 11.1) than male IVC (122.5 +/- 15.0). Phenylephrine contraction in 0 Ca(2+) Krebs was insignificantly less in female (4.8 +/- 1.8) than male IVC (7.2 +/- 1.7), suggesting little difference in the intracellular Ca(2+) release mechanism. In contrast, the [Ca(2+)](e)-dependent contraction was significantly reduced in female than male IVC. Also, contraction to membrane depolarization by 96 mM KCl, which stimulates Ca(2+) influx, was less in female (129.7 +/- 16.7) than male IVC (319.7 +/- 30.4), supporting sex differences in Ca(2+) entry. Acetylcholine relaxation was greater in female (max 80.6% +/- 4.1%) than male IVC (max 48.0% +/- 6.1%), suggesting sex differences in the endothelium-dependent relaxation pathway. Western blots revealed greater amounts of ERalpha, ERbeta, and GPR30 in female than male IVC. ER agonists caused concentration-dependent relaxation of phenylephrine contraction in female IVC. E2-induced relaxation (max 76.5% +/- 3.4%) was more than DPN (74.8% +/- 9.1%), PPT (71.4% +/- 12.5%), and ICI 182,780 (67.4% +/- 7.8%), and was similar in L-NAME-treated and nontreated IVC.

CONCLUSION

The reduced alpha-adrenergic, AngII, depolarization-induced, and [Ca(2+)](e)-dependent venous contraction in female rats is consistent with sex differences in the Ca(2+) entry mechanisms, possibly due to enhanced endothelium-dependent vasodilation and increased ER expression/activity in female rats. E2/ER-mediated venous relaxation in female rats is not prevented by NOS blockade, suggesting activation of an NO-independent relaxation pathway. The decreased venous contraction and enhanced E2/ER-mediated venous relaxation would lead to more distensible veins in female rats.

Elevated sex steroid hormones in great saphenous veins in men

INTRODUCTION

High serum levels of estradiol are associated with clinical evidence of varicose veins in women; however, the relationship between serum sex steroid hormones and varicose veins in men is unclear. To address this issue, serum levels of testosterone, estradiol, and androstenedione were determined in the great saphenous (GSV) and cubital veins of men with varicose veins. Messenger RNA (mRNA) expression of sex steroid hormones, metabolizing enzymes, and their receptors was investigated in tissue samples of leg veins.

METHODS

This prospective study included 40 men, comprising 20 with varicose veins and reflux of the GSV (VM) and 20 with healthy veins (HM). All limbs were assessed by duplex ultrasound scanning of selected superficial and deep leg veins. Blood samples were taken from the cubital vein and from the GSV. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis for sex steroid hormones, their metabolizing enzymes, and receptors in saphenous veins was performed in tissue samples of varicose (n = 6) and healthy veins (n = 6).

RESULTS

The VM group had significantly higher (P < .001) mean levels for serum testosterone (44.9 nmol/L; range, 8.8-225.1) and estradiol (242.2 pmol/L; range, 79-941) in varicose saphenous veins compared with cubital veins (testosterone, 15.5 nmol/L; range, 8.4-23.3; estradiol, 93.2 pmol/L; range, 31-147). Moreover, significantly (P < .001) higher mean serum estradiol levels (133.2 pmol/L; range, 63-239) were detected in the saphenous veins of the HM group compared with cubital veins (88.15 pmol/L; range, 37-153). Both groups had similar blood counts and serum androstenedione levels in the upper and lower extremity. Interestingly, qRT-PCR revealed that the mRNA expression of 5alpha-reductase type 1, 5alpha-reductase type 2, 17, 20 lyase, 17beta-hydroxysteroid dehydrogenase (17beta-HSD), aromatase and 3beta-HSD type 2, androgen and estrogen receptor 1 was down-regulated (P < .05) in all samples of varicose veins vs veins obtained from healthy men.

CONCLUSION

Elevated serum estradiol and testosterone levels were detected in men with varicose veins and reflux in the GSV compared with the patient's own arm veins. Enzymes and hormonal receptors involved in steroid metabolism were down-regulated in patients with GSV reflux and varicose veins, suggestive of a negative feedback regulation. These data support the notion of a possible causal relationship between sex steroids and varicose veins in men.

Does the progesterone receptor genetic polymorphism +331G/A hPR influence the risk of venous thromboembolism among postmenopausal women using hormone therapy? The ESTHER Study

Hormone therapy (HT) increases venous thromboembolism (VTE) risk among postmenopausal women. Data on the influence of steroids receptors polymorphisms on this association remain scarce. Since progesterone receptor (hPR) is expressed in human veins and specific progestogens increase VTE risk, we investigated the impact of the functional +331G/A hPR polymorphism on the association of VTE with HT. Using the data of the ESTHER study, we showed that ORs for VTE in current users of progesterone or progestins were not significantly different by hPR+331G/A genotype status. hPR polymorphism appears not to have a significant effect on VTE risk related to HT.

Results of an Electronic Mail Survey on Hormones and Telangiectasias

BACKGROUND

The relationship between the development of telangiectasias and hormonal intake has not been well studied and is empirically managed by phlebologists.

OBJECTIVE

To understand the behavior of the international phlebologic community regarding the treatment of leg telangiectasia in patients taking oral contraceptives or receiving postmenopausal hormone replacement therapy.

METHODS

Simple questions concerning the causal effects of hormones, their influence on treatment, and general behavior were asked by an electronic mail questionnaire sent to 131 phlebologists in my personal database.

RESULTS

The 61 answers received show the existence of two opposite "parties" concerning the influence of hormones on telangiectasia: cause and treatment.

CONCLUSION

Opposite opinions without any scientific basis underline the ignorance surrounding a subject that concerns 50% of our patients.

Role of progesterone signaling in the regulation of G-protein levels in female chronic constipation

BACKGROUND & AIMS

Chronic constipation caused by slow transit is common in women with an F/M ratio of 9:1. The cause and mechanisms responsible for this syndrome are unknown. Progesterone has been suggested as a possible contributing factor. Our aim was to investigate the site and mechanisms responsible for this colonic motility disorder.

METHODS

Seven women with intractable constipation and slow transit time underwent colectomy and 6 women who underwent a left colectomy for adenocarcinoma (controls) were studied. Dissociated colonic circular muscle cells were obtained by enzymatic digestion. Changes in G-protein levels were measured by Western blot. The messenger RNA (mRNA) expression of Galpha q and progesterone receptors was determined by reverse-transcription polymerase chain reaction and Northern blot.

RESULTS

Muscle cells from patients with chronic constipation exhibited impaired contraction in response to receptor-G-protein-dependent agonists (cholecystokinin [CCK], acetylcholine) and in response to the direct G-protein activator guanosine 5'-O-(3-thiophosphate). Contraction was normal with receptor-G-protein-independent agonists (diacylglycerol and KCl). Western blot showed down-regulation of Galpha q/11 and up-regulation of Galpha s proteins in patients with chronic constipation. The mRNA expression of Galpha q was lower and the progesterone receptors were overexpressed in patients with chronic constipation compared with controls. These abnormalities were reproduced in vitro by pretreatment of normal colonic muscle cells with progesterone for 4 hours.

CONCLUSIONS

Slow transit chronic constipation in women may be caused by down-regulation of contractile G proteins and up-regulation of inhibitory G proteins, probably caused by overexpression of progesterone receptors.

Progesterone receptor gene inactivation and CpG island hypermethylation in human leukemia cancer cells

Previous studies showed that progesterone receptor (PR), one of the hormone receptor superfamily, was only connected with the sex-correlated cancers such as breast cancer, endometrial cancer, prostate cancer, etc. This article deals with the PR gene in leukemia. We investigated the methylation status and the expression of the two different PR isoforms, PRA and PRB, in three leukemia cancer cell lines using methylation-specific polymerase chain reaction (MSP-PCR) and reverse transcription-PCR. The correlation of PR methylation and expression together with DNA methyltransferase (DNMT1) was further studied. We found that DNMT1 is required to maintain CpG methylation and aberrant gene silencing of PR gene in human leukemia cancer cells. The activity of 5-aza-2'-deoxycytidine in demethylation and gene reactivation may be through depleting cellular DNMT1 levels. In addition, extensive methylation of PRA and PRB was also observed in leukemia samples. Our results suggest that PR CpG island aberrant hypermethylation could be one molecular and genetic alteration in leukemia.

Pathogenesis of varicose veins

BACKGROUND

varicose veins are present in up to 40% of the population. They may be associated with considerable morbidity. Around 70% of patients with chronic venous insufficiency have evidence of superficial venous incompetence on duplex imaging.

METHODS

in this publication we review the evidence available regarding the pathogenesis of varicose veins.

RESULTS

a number of theories have been suggested. The present data suggests that abnormalities in the venous endothelium and smooth muscle cells result in vein wall dilatation with secondary valvular incompetence. However, there is also evidence to support acquired venous valve failure. Congenital venous valve abnormalities have not been well studied.

CONCLUSION

further work is required on this relatively neglected topic. The use of improved imaging such as high-resolution ultrasound is likely to significantly improve our understanding of venous valve function and pathology.

Nongenomic vasodilator action of progesterone on primate coronary arteries

In the present investigation, we test the hypothesis that progesterone can rapidly relax, via a nongenomic mechanism, persistent flow occluding, agonist-activated coronary artery (CA) vasospasm, and hyperreactive vascular muscle cell (VMC) Ca(2+) responses in ovariectomized rhesus monkeys. CA vasospasm, induced by injection of 100 microM serotonin and 1 microM U-46619 (5-HT+U; 1 ml/30 s), resulted in a decrease in CA diameter (phi) from 1.8 +/- 0.2 to 0.3 +/- 0.1 mm at the site of focal constriction. Injection of 100 ng progesterone into the CA significantly relieved the severe vasoconstriction (1.3 +/- 0.2 mm) and reestablished distal flow in 3 min; the preconstriction phi was completely restored in 8.2 +/- 2.6 min (n = 6). Similarly, cell impermeant albumin-conjugated progesterone, but not albumin-conjugated 17 beta-estradiol, decreased 5-HT+U stimulated VMC Ca(2+) responses (250 +/- 34% of basal 30 min after stimulation) back to the prestimulation level (113 +/- 17% of basal) in 25 min (half time = 7 min). The presence of a rapid vasodilator action of progesterone in the primate CA and isolated VMC suggests its benefits in hormone replacement therapy may also include nongenomic vascular relaxant actions.

Nonsaphenous superficial vein reflux

BACKGROUND

Information on nonsaphenous superficial venous reflux is lacking. This study was designed to determine the prevalence of reflux in nonsaphenous veins, their association and correlation with risk factors, and signs and symptoms of chronic venous disease (CVD).

METHODS

Information on 835 limbs in patients with signs and symptoms of CVD were prospectively entered into a customized database. These patients had been referred from the venous clinic to the vascular laboratory for color-flow duplex scanning evaluation of the lower-limb veins. All patients were examined for reflux in the standing and sitting positions. Nonsaphenous reflux was defined as that in superficial veins that are not part of the greater or lesser saphenous systems. Particular attention was paid to the patterns of reflux and anatomy of the nonsaphenous veins from the proximal to the distal ends, including their connections with the saphenous and deep veins.

RESULTS

Nonsaphenous venous reflux was found in 84 limbs (10%) of 72 patients, 67 of whom were women. The mean number of pregnancies in these patients was higher than that of 100 randomly selected women with saphenous reflux (3.2 vs 2.2). According to CEAP classification, 90% of the limbs were in CVD classes 1 through 3 and only 10% had skin damage (classes 4-6). Symptoms were present in 67 limbs (80%). Forty-two limbs (50%) had reflux in tributaries of lateral, posterior, and medial thigh. These veins were connected with perforators uniting with the deep femoral, femoral, and muscular veins of the thigh in 36 limbs. Reflux in these perforators was detected in 19 limbs. Reflux arising from the pelvic veins was found in 29 limbs (34%), 18 of which were from vulvar veins medial to saphenofemoral junction and 11 of which were from veins in the gluteal area. Incompetent veins from the sciatic nerve were found in nine limbs (10%). Reflux in the vein of the popliteal fossa was found in seven limbs (8%). Reflux in knee tributaries was detected in three limbs (4%), two of which were connected with posterolateral knee perforators and one with the posterior tibial nerve veins.

CONCLUSIONS

The prevalence of nonsaphenous reflux in our practice was 10%. The vast majority of these patients (93%) were women with a mean of 3.2 pregnancies. Ninety percent of these limbs have signs and symptoms assigned to CVD classes 1 to 3. These data may simply reflect the referral pattern, but also a possible association with female sex and number of pregnancies. The unusual anatomy of these veins stresses the importance of color-flow duplex scanning before surgery.

Vascular endothelial growth factor is modulated in vascular muscle cells by estradiol, tamoxifen, and hypoxia

Vascular endothelial growth factor (VEGF) promotes neovascularization, microvascular permeability, and endothelial proliferation. We described previously VEGF mRNA and protein induction by estradiol (E2) in human endometrial fibroblasts. We report here E2 induction of VEGF expression in human venous muscle cells [smooth muscle cells (SMC) from human saphenous veins; HSVSMC] expressing both ER-alpha and ER-beta estrogen receptors. E2 at 10(-9) to 10(-8) M increases VEGF mRNA in HSVSMC in a time-dependent manner (3-fold at 24 h), as analyzed by semiquantitative RT-PCR. This level of induction is comparable with E2 endometrial induction of VEGF mRNA. Tamoxifen and hypoxia also increase HSVSMC VEGF mRNA expression over control values. Immunocytochemistry of saphenous veins and isolated SMC confirms translation of VEGF mRNA into protein. Immunoblot analysis of HSVSMC-conditioned medium detects three bands of 18, 23, and 28 kDa, corresponding to VEGF isoforms of 121, 165, and 189 amino acids. Radioreceptor assay of the conditioned medium produced by E2-stimulated HSVSMC reveals an increased VEGF secretion. Our data indicate that VEGF is E2, tamoxifen, and hypoxia inducible in cultured HSVSMC and E2 inducible in aortic SMC, suggesting E2 modulation of VEGF effects in angiogenesis, vascular permeability, and integrity.

Evidence for progesterone receptors in the human fetoplacental vascular tree

The presence of progesterone receptors (PR) throughout the human term fetoplacental vascular tree was investigated. By reverse transcription-polymerase chain reaction (RT-PCR), we showed expression of PR mRNAs in stem villi vessels, chorionic arteries and veins, and umbilical arteries and veins. Binding studies and Scatchard analysis revealed a single class of high-affinity binding sites for (3)H-R5020 (promegestone) in cytosolic extracts of all placental vessels, with K(d) values in the range of 2.5-4 nM. High levels of PR were detected in placental vessels compared to other vascular tissues. Thus, maximum binding capacities of stem villi vessels, chorionic arteries and veins, and umbilical arteries and veins were 247 +/- 25, 377 +/- 58, 295 +/- 40, 371 +/- 118, and 672 +/- 144 fmol/mg protein, respectively. Endothelial cell elimination in chorionic arteries did not significantly modify the number of PR. RT-PCR and binding studies also assessed PR expression in cultured placental vascular smooth muscle cells isolated from stem villi vessels. All these data suggested that most of the PR of fetoplacental vessels were from the media. In conclusion, we report here the first evidence of the presence of PR in the muscular layer of human term fetoplacental vessels. This finding, together with the high progesterone concentrations in cord blood, suggests that the interactions between the PR and its ligand may play a role in the physiology and physiopathology of human fetoplacental vascularization.

Effects of combined sex hormone replacement therapy on small artery biomechanics in pharmacologically ovariectomized rats

OBJECTIVES

The purpose of this study was to determine the effects of long-term combined sexual hormone replacement therapy on the biomechanical properties of the small artery wall in castrated female rats.

METHODS

30 non-pregnant mature female Sprague-Dawley rats were pharmacologically ovariectomized with 750 microg/kg triptorelin im. every 4th week. Ten of them received combined hormone replacement in form of 15 mg/kg medroxyprogesterone acetate (MPA) im. every 2 weeks and 450 microg/kg estradiol propionate im. once a week. Ten castrated animals received MPA only. Ten control, castrated animals were given the vehicles of these steroids. Ten other animals were kept parallelly, receiving the vehicles of all drugs (control animals). After 12 weeks of treatment cylindrical segments of the saphenous artery were isolated and cannulated at both ends and subjected to in vitro microarteriographic test. Pressure diameter curves, in the range of 0-200 mmHg, were recorded from segments in normal Krebs-Ringer (nKR) solution, in contraction with norepinephrine (1.6 x 10(-5) M), and then in relaxation with papaverine (2.8 x 10(-5) M). Biomechanical parameters were calculated based on the pressure diameter curves.

RESULTS

Combined hormone replacement therapy significantly increased the passive diameter of small arteries, as compared to those from ovariectomized animals without hormone replacement. MPA monotherapy did not alter the vessel diameter, the inner radii at 100 mmHg intraluminal pressure were, 300+/-9 microm in the control castrated, 340+/-7 microm in the estradiol + MPA replaced and 306+/-8 microm in the MPA treated groups (P < 0.05 between the control castrated and the combined treatment groups). The vascular reactivity to norepinephrine or papaverine was not changed significantly either by combined hormone replacement or by MPA monotherapy when compared with ovariectomized controls. No significant alterations were found in wall thickness and distensibility.

CONCLUSIONS

These results suggest that chronic medroxyprogesterone pretreatment does not influence the geometric, elastic and contractile properties of small arteries in castrated female rats. The combination of MPA + estradiol increased the morphological lumen: the morphological vasodilatation induced by estrogen, described earlier, was not affected by the addition of this progestin to the regimen.

Syncytiotrophoblastic fragments in first-trimester decidual veins: evidence of placental perfusion by the maternal circulation early in pregnancy

OBJECTIVE

To determine whether maternal placental perfusion occurs in the first trimester, this study compared veins in endometrium with those in decidua. We hypothesize that veins draining the placenta become dilated and contain syncytiotrophoblastic fragments.

STUDY DESIGN

Normal late-secretory endometrial biopsy specimens (n = 10) were compared with elective abortion decidua at 7 to 11 weeks (n = 100). Tissue sections were processed by routine staining and immunohistochemical studies. The cross sections of veins and glands were counted in 25 decidual biopsy specimens, and the number of syncytiotrophoblastic fragments in veins or glands was determined. Statistical significance by chi(2) or linear regression analysis was P <.05.

RESULTS

All sets of decidua had dilated veins; no secretory endometrium did. Intravenous syncytiotrophoblastic fragments were seen in 91 of 100 sets of decidua. There were more syncytial elements in veins (572/6845, 8.4%) than in glands (13/23,310, 0.06%) (P <.001).

CONCLUSION

Decidual veins were distended and contained syncytiotrophoblastic fragments, consistent with maternal intervillous perfusion in the first trimester.

Progesterone modulates estradiol actions: acute effects at physiological concentrations

The progestin element of hormone replacement therapy may reduce the cardioprotective actions of the estrogen component. Only high concentrations (microM) of progesterone directly relaxed U46619 (9,11-dideoxy-9alpha, 11alpha-methanoepoxy prostaglandin F2alpha)-pre-contracted porcine coronary artery rings. A low concentration of progesterone (1 nM), with no effects of its own, shifted the relaxation curves of bradykinin and calcium ionophore A23187 to the right while not affecting those of sodium nitroprusside and levcromakalim. The negative influence that 1 nM progesterone exerted on bradykinin- and A23187-mediated relaxation was diminished when 1 nM 17beta-estradiol was concomitantly added to the bathing medium. Conversely, the potentiating actions of 1 nM 17beta-estradiol on relaxations elicited by sodium nitroprusside and levcromakalim were reduced following simultaneous treatment with the same concentrations of progesterone. These findings represent the first evidence for an acute in vitro vascular effect of progesterone at a physiologically relevant concentration and concur with previous in vivo reports demonstrating that progesterone may diminish the beneficial effects of estrogens.

Estrogen and progesterone receptors in normal and varicose saphenous veins

The presence of estrogen and progesterone receptors was investigated in the walls of normal and varicose veins. Cryostat sections from the saphenous veins of 29 normal individuals, and varicose and normal vein segments of 32 patients with varicose veins, were stained with anti-estrogen or anti-progesterone receptor antibodies. Nuclear stain intensity was scored by three independent observers. Receptors to both hormones were detected in the nuclear regions of the intima and media in females and males. In the adventitia, estrogen and the progesterone receptors were found only in nuclei of the vasa vasorum. Estrogen receptor levels were lower in non-varicose segments of varicose veins compared with normal veins. In varicose segments, estrogen receptors were more abundant than in the non-varicose parts of the same vein, especially in females. Similarly, progesterone receptor levels in the non-varicose portions were higher in females. These gender differences may be related to hormonal action. However, these differences may also be age related. These findings may be related to the involvement of sex-hormones in varicosis, by mechanisms as yet unknown.

Vascular remodeling in varicose veins

The present study describes the histopathologic aspects of varicose (n=29; mean age, 52 +/- 12 years) and normal saphenous veins (n=17; mean age, 51 +/- 12 years) of patients from a similar age group. We focused on the changes that occur in the circular layer of the venous wall. We examined the venous walls by light microscopy and transmission electronmicroscopy. A semiquantitative grading system was used to assess the smooth muscle cell (SMC) hypertrophy and the change that occurs in the elastin pattern. The volume densities (Vv) of SMC and collagen were measured as well as the diameter of the SMC, and the nuclei of SMC per fixed area were counted. The varicose vein wall differed from the normal saphenous vein by the presence of hypertrophic SMC as well as disorganized elastin patterns. A correlation between the hypertrophic SMC and an abnormal elastin pattern was observed (r=0.658, p<0.001). Ultrastructurally, the SMC show prominent microherniations and vesicles that bud from the cell. These vesicles contain microfilaments and microtubuli, although no other organelles could be detected. The elastin fibers are disrupted from the hypertrophic SMC. No significant difference could be detected in both the Vv of SMC and the Vv of collagen. The diameter of the SMC in the varicose vein (d=9.45 +/- 1.22 microm) differs significantly from that in the normal saphenous vein (d=6.22 +/- 1.47 microm) (p<0.001). Also, the nuclei of SMC per fixed area differs significantly between the varicose (87 +/- 18) and nonvaricose (117 +/- 24) veins (p<0.001). We conclude that the cellular hypertrophy of the SMC and the microherniations could be the basis for disruption of the elastin fibers connected to the SMC in varicose veins. Disrupted connections between SMC and elastin fibers could in turn induce the weakness of the venous wall observed in varicose vein disease.

In vitro modulation of primate coronary vascular muscle cell reactivity by ovarian steroid hormones

Susceptibility to drug-induced coronary vasospasm in rhesus monkeys increases after removal of the ovaries and can be normalized by adding back physiological levels of estradiol-17ss (E2) and/or natural progesterone (P) in vivo as reported recently by our group. Furthermore, the reactivity status (Ca2+ and protein kinase C responses) of freshly isolated and primary culture coronary artery vascular muscle cells (VMC) mimic the intact coronary artery responses to 5-HT + U46619. Since coronary reactivity is maintained in the isolated VMC, we hypothesized that the reactivity state inherent in the VMC was modulated directly by ovarian steroids in vitro as in the whole animal. To test this hypothesis, we treated hyperreactive VMC from ovariectomized (ovx) monkeys in vitro with E2 or P and measured VMC reactivity to combined stimulation with 5-HT and U46619, as determined by the amplitude and especially the duration of intracellular Ca2+ signals, as well as protein kinase C (PKC) activation/translocation. VMC were treated for 12 96 h with 3 100 pg/ml E2 (10 365 pM) and/or 0.3 3 ng/ml P (0.95 9.5 nM). Hyperreactive responses to the combination of 5-HT and U46619 in untreated VMC were significantly and dose-dependently reduced by treatment in vitro with physiological levels of either E2 or P for at least 24 h. Both the early transient and late sustained increases in intracellular Ca2+ and PKC translocation were blunted, and the effects of 0.2 nM E2 and 3.2 nM P were specifically antagonized by the receptor blockers ICI 182,780 (200 nM) and RU486 (15 nM), respectively. Antibodies to the estrogen receptor and progesterone receptor labeled nuclei in VMC, which were also positively labeled by a smooth muscle myosin heavy chain monoclonal antibody. These data indicate that natural ovarian steroids directly reduce hyperreactive 5-HT and thromboxane A2-stimulated Ca2+ and PKC responses of coronary artery VMC from surgically menopausal rhesus macaques. We hypothesize that vascular hyperreactivity, which may be a critical factor involved in the increased incidence of coronary artery vasospasm and ischemic heart disease in postmenopausal women, can be normalized by E2 and/or P through direct actions on coronary artery vascular muscle cells.

Variable venous anatomy of the popliteal fossa demonstrated by duplex scanning

BACKGROUND

Location of the sapheno-popliteal junction (SPJ) is highly variable and therefore often difficult to identify correctly at operation. The anatomy is often complicated by associated pathology in the popliteal fossa, which makes clinical examination unreliable.

OBJECTIVE

The purpose of our study was to quantify this variability and record other concomitant pathology in patients with sapheno-popliteal junction incompetence.

METHODS

We retrospectively reviewed duplex scans of 544 patients with 638 legs showing SPJ incompetence, from a total of approximately 4000 patients attending our laboratory between August 1993 and August 1995.

RESULTS

We found that 51% of sapheno-popliteal junctions were located within 2 cm above the popliteal skin crease and a further 36% within 4 cm, with the remaining situated anywhere between 4 and 10 cm above the popliteal skin crease. Additionally 18% of patients had either Giacomini or gastrocnemius vein incompetence in addition to SPJ incompetence, further complicating the clinical picture.

CONCLUSION

When SPJ incompetence is suspected, duplex scanning identifies the exact location of the junction and other associated pathology in the popliteal fossa, and allows the position of the junction to be marked on the leg preoperatively.

Effect of Steroid Hormones and Retinoids on the Formation of Capillary-Like Tubular Structures of Human Microvascular Endothelial Cells in Fibrin Matrices Is Related to Urokinase Expression

Angiogenesis, the formation of new capillary blood vessels, is a feature of a variety of pathological processes. To study the effects of a specific group of hormones (all ligands of the steroid/retinoid/thyroid hormone receptor superfamily) on the angiogenic process in humans, we have used a model system in which human microvascular endothelial cells from foreskin (hMVEC) are cultured on top of a human fibrin matrix in the presence of basic fibroblast growth factor and tumor necrosis factor-α. This model mimics the in vivo situation where fibrin appears to be a common component of the matrix present at sites of chronic inflammation and tumor stroma. Our results show that testosterone and dexamethasone are strong inhibitors and all-trans retinoic acid (at-RA) and 9-cis retinoic acid (9-cis RA) are potent stimulators of the formation of capillary-like tubular structures. These effects are mediated by their respective nuclear hormone receptors as demonstrated by the use of specific synthetic receptor agonists and antagonists. 17β-estradiol, progesterone, and 1,25-dihydroxyvitamin D3 did not affect or only weakly affected in vitro angiogenesis, which may be related to the lack of significant nuclear receptor expression. Although hMVEC express both thyroid hormone receptors α and β, no effect of thyroid hormone on tube formation was found. The effects of testosterone, dexamethasone,at-RA, and 9-cis RA on tube formation were accompanied by parallel changes in urokinase-type plasminogen activator (u-PA) expression, at both mRNA and antigen levels. Exogenous suppletion of the medium with single chain u-PA enhances tube formation in our in vitro model, whereas quenching of u-PA activity (but not of tissue-type plasminogen activator activity) or of u-PA binding to u-PA receptor by specific antibodies suppressed basal and retinoid-stimulated tube formation. Moreover, addition of scu-PA to testosterone- or dexamethasone-treated hMVEC restored the suppressed angiogenic activity for a substantial part. Aprotinin, an inhibitor of plasmin activity, completely inhibited tube formation, indicating that the proteolytic properties of the u-PA/u-PA receptor complex are crucial in this process. Our results show that steroid hormones (testosterone and dexamethasone) and retinoids have strong, but opposite effects on tube formation in a human in vitro model reflecting pathological angiogenesis in the presence of fibrin and inflammatory mediators. These effects can be explained by hormone-receptor–mediated changes in u-PA expression, resulting in enhanced local proteolytic capacity of the u-PA/u-PA receptor complex.

© 1998 by The American Society of Hematology.

Effect of Steroid Hormones and Retinoids on the Formation of Capillary-Like Tubular Structures of Human Microvascular Endothelial Cells in Fibrin Matrices Is Related to Urokinase Expression

Angiogenesis, the formation of new capillary blood vessels, is a feature of a variety of pathological processes. To study the effects of a specific group of hormones (all ligands of the steroid/retinoid/thyroid hormone receptor superfamily) on the angiogenic process in humans, we have used a model system in which human microvascular endothelial cells from foreskin (hMVEC) are cultured on top of a human fibrin matrix in the presence of basic fibroblast growth factor and tumor necrosis factor-α. This model mimics the in vivo situation where fibrin appears to be a common component of the matrix present at sites of chronic inflammation and tumor stroma. Our results show that testosterone and dexamethasone are strong inhibitors and all-trans retinoic acid (at-RA) and 9-cis retinoic acid (9-cis RA) are potent stimulators of the formation of capillary-like tubular structures. These effects are mediated by their respective nuclear hormone receptors as demonstrated by the use of specific synthetic receptor agonists and antagonists. 17β-estradiol, progesterone, and 1,25-dihydroxyvitamin D3 did not affect or only weakly affected in vitro angiogenesis, which may be related to the lack of significant nuclear receptor expression. Although hMVEC express both thyroid hormone receptors α and β, no effect of thyroid hormone on tube formation was found. The effects of testosterone, dexamethasone,at-RA, and 9-cis RA on tube formation were accompanied by parallel changes in urokinase-type plasminogen activator (u-PA) expression, at both mRNA and antigen levels. Exogenous suppletion of the medium with single chain u-PA enhances tube formation in our in vitro model, whereas quenching of u-PA activity (but not of tissue-type plasminogen activator activity) or of u-PA binding to u-PA receptor by specific antibodies suppressed basal and retinoid-stimulated tube formation. Moreover, addition of scu-PA to testosterone- or dexamethasone-treated hMVEC restored the suppressed angiogenic activity for a substantial part. Aprotinin, an inhibitor of plasmin activity, completely inhibited tube formation, indicating that the proteolytic properties of the u-PA/u-PA receptor complex are crucial in this process. Our results show that steroid hormones (testosterone and dexamethasone) and retinoids have strong, but opposite effects on tube formation in a human in vitro model reflecting pathological angiogenesis in the presence of fibrin and inflammatory mediators. These effects can be explained by hormone-receptor–mediated changes in u-PA expression, resulting in enhanced local proteolytic capacity of the u-PA/u-PA receptor complex.

© 1998 by The American Society of Hematology.

Ovarian steroid protection against coronary artery hyperreactivity in rhesus monkeys

Our hypothesis was that estrogen and progesterone modulate coronary artery reactivity in rhesus monkeys. Adult ovariectomized (ovx) monkeys were treated for 1, 2, or 4 wk with physiological concentrations of 17 beta-estradiol (E2), natural progesterone (P), and/or therapeutic levels of medroxyprogesterone acetate (MPA). Steroid concentrations in venous blood, coronary artery estrogen receptor (ER) and progesterone receptor (PR) localization, and isolated vascular muscle cell (VMC) Ca2+ and protein kinase C responses to serotonin and U46619 (a thromboxane A2 mimetic) were measured. Ovx monkey VMC responses were hyperreactive, showing prolonged increases in intracellular Ca2+ and protein kinase C that correlated with exaggerated in vivo coronary artery vasoconstrictor responses. The hyperreactive Ca2+ responses were abolished by in vivo treatment with E2 and/or P. However, VMC from ovx monkeys treated with the combination of E2 and MPA or E2, P, and MPA remained hyperreactive to vasoconstrictor stimuli, suggesting that MPA negated the protective effects of E2. ER were detected primarily in interstitial and endothelial cells and a minor fraction of the VMC. PR were localized to coronary artery VMC and interstitial cell nuclei. In vivo treatment of ovx monkeys with E2 tended to up-regulate PR in VMC, but MPA appeared to down-regulate PR expression. These results suggest that E2 and P replacement decreases coronary artery reactivity through direct interactions with ER and PR in coronary artery VMC.

Distribution of progesterone receptor in chicken: novel target organs for progesterone and estrogen action

Expression of progesterone receptor (PR) in various organs of sexually immature chickens and after estrogen treatment was studied by immunohistochemical and Western blotting analyses. Constitutive PR expression was observed in the mesothelium and stroma of the esophagus, proventriculus, liver, spleen, pancreas, heart and lung. In the urogenital tract, PR was expressed in the mesothelial and stromal cells and smooth muscle of blood vessels. Estrogen treatment induced PR expression in the stroma and smooth muscle of the gall bladder and in the epithelium and stroma of the trachea. In the ovary of immature chickens PR was localized in the epithelium, stroma and smooth muscle and was induced in the granulosal cells by estrogen. In most tissues there was more PR-B than PR-A expression and this PR-B dominance remained after estrogen treatment. These results suggest that progesterone and estrogen may have physiological effects on many organs outside the genital tract not previously known as steroid-target tissues.

Venous disease: from pathophysiology to quality of life

Venous insufficiency is a multifactorial pathology that has an important impact on the quality of life of the patients. The primary factor of venous disease is an abnormal wall distensibility, which seems to be correlated with genetic factors. Facilitating factors include hormonal impregnation and prolonged hydrostatic load, particularly under conditions where the control of the sympathetic nervous system is reduced by an increase in local temperature. The resulting valvular incompetence, combined with the augmented hydrostatic load, leads to varicosis and venous stasis. The ensuing tissue hypoxia and local edema favor inflammation and infection, which ultimately favor the occurrence of ulcers. The available data on the impact of the disease suggest a relation between the physiopathological phenomena and some parameters of health-related quality of life.

Estrogen receptors in the cardiovascular system

Various direct effects of estradiol on arterial tissue suggest the presence of estrogen receptors (ER) in the vascular wall. The study of ER detection has made an important progress over the last 10 years with the advent and widespread use of monoclonal antibodies against the receptor protein. Using immunocytochemical methods and monoclonal antibodies, we have detected estrogen receptors in the tunica media of arteries from the reproductive tract; their concentration depends on the hormonal status. These receptors are apparently absent from saphenous veins (taken from patients undergoing surgical removal of varicose veins). We also document here results on the cardiovascular system we discuss their implications in blood vessel relaxation and cell proliferation.