The presence of intraperitoneal, retroperitoneal and pleural fluid in acute Puumala hantavirus infection

BACKGROUND

Puumala hantavirus (PUUV) causes most cases of haemorrhagic fever with renal syndrome (HFRS) in Europe. PUUV infection is characterised by acute kidney injury, thrombocytopenia and increased capillary leakage. Typical symptoms are fever, headache, nausea, abdominal and back pain. This study aimed to evaluate the amount and distribution of intraperitoneal, retroperitoneal and pleural fluid and the association of fluid collections to the symptoms and clinical findings in patients with acute PUUV infection.

METHODS

Abdominal magnetic resonance imaging (MRI) was performed on 27 hospitalised patients with acute PUUV infection. The clinical and laboratory findings and patients' symptoms were analysed in relation to the imaging findings. The thickness of the fluid collections was measured in millimetres (mm) from axial images.

RESULTS

Fluid collections were found in all patients. The amount of intraperitoneal fluid correlated positively with plasma C-reactive protein (CRP) level (r = 0.586, p = .001), while it had an inverse correlation with serum creatinine concentration (r = -0.418, p = .030). Retroperitoneal fluid also correlated inversely with serum creatinine and cystatin C concentrations (r = -0.501, p = .008 and r = -0.383, p = .048, respectively). The amount of fluid was not greater in patients with abdominal or back pain. Patients with back pain had higher serum creatinine compared with patients without back pain, 452 µmol/L (range 88-1071) vs. 83 µmol/L (range 60-679), p = .004.

CONCLUSIONS

Fluid collections were found in all patients. A greater amount of intraperitoneal fluid associates with higher CRP concentrations but not with higher serum creatinine levels. Back pain associates with higher creatinine level but not with the presence of fluids.

Discontinuation of anti-PD-1 antibody therapy in the absence of disease progression or treatment limiting toxicity: clinical outcomes in advanced melanoma

BACKGROUND

Programmed cell death protein 1 (PD-1) blocking monoclonal antibodies improve the overall survival of patients with advanced melanoma but the optimal duration of treatment has not been established.

PATIENTS AND METHODS

This academic real-world cohort study investigated the outcome of 185 advanced melanoma patients who electively discontinued anti-PD-1 therapy with pembrolizumab (N = 167) or nivolumab (N = 18) in the absence of disease progression (PD) or treatment limiting toxicity (TLT) at 14 medical centres across Europe and Australia.

RESULTS

Median time on treatment was 12 months (range 0.7-43). The best objective tumour response at the time of treatment discontinuation was complete response (CR) in 117 (63%) patients, partial response (PR) in 44 (24%) patients and stable disease (SD) in 16 (9%) patients; 8 (4%) patients had no evaluable disease (NE). After a median follow-up of 18 months (range 0.7-48) after treatment discontinuation, 78% of patients remained free of progression. Median time to progression was 12 months (range 2-23). PD was less frequent in patients with CR (14%) compared with patients with PR (32%) and SD (50%). Six out of 19 (32%) patients who were retreated with an anti-PD-1 at the time of PD obtained a new antitumour response.

CONCLUSIONS

In this real-world cohort of advanced melanoma patients discontinuing anti-PD-1 therapy in the absence of TLT or PD, the duration of anti-PD-1 therapy was shorter when compared with clinical trials. In patients obtaining a CR, and being treated for >6 months, the risk of relapse after treatment discontinuation was low. Patients achieving a PR or SD as best tumour response were at higher risk for progression after discontinuing therapy, and defining optimal treatment duration in such patients deserves further study. Retreatment with an anti-PD-1 at the time of progression may lead to renewed antitumour activity in some patients.

CLINICAL TRIAL REGISTRATION

NCT02673970 (https://clinicaltrials.gov/ct2/show/NCT02673970?cond=melanoma&cntry=BE&city=Jette&rank=3).

Role of the endocannabinoid system in obesity induced by neuropeptide Y overexpression in noradrenergic neurons

Objective:

Endocannabinoids and neuropeptide Y (NPY) promote energy storage via central and peripheral mechanisms. In the hypothalamus, the two systems were suggested to interact. To investigate such interplay also in non-hypothalamic tissues, we evaluated endocannabinoid levels in obese OE-NPY^DβH mice, which overexpress NPY in the noradrenergic neurons in the sympathetic nervous system and the brain.

Methods:

The levels of the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG) were measured in key regulatory tissues, that is, hypothalamus, pancreas, epididymal white adipose tissue (WAT), liver and soleus muscle, over the development of metabolic dysfunctions in OE-NPY^DβH mice. The effects of a 5-week treatment with the CB1 receptor inverse agonist AM251 on adiposity and glucose metabolism were studied.

Results:

2-AG levels were increased in the hypothalamus and epididymal WAT of pre-obese and obese OE-NPY^DβH mice. Anandamide levels in adipose tissue and pancreas were increased at 4 months concomitantly with higher fat mass and impaired glucose tolerance. CB1 receptor blockage reduced body weight gain and glucose intolerance in OE-NPY^DβH to the level of vehicle-treated wild-type mice.

Conclusions:

Altered endocannabinoid tone may underlie some of the metabolic dysfunctions in OE-NPY^DβH mice, which can be attenuated with CB1 inverse agonism suggesting interactions between endocannabinoids and NPY also in the periphery. CB1 receptors may offer a target for the pharmacological treatment of the metabolic syndrome with altered NPY levels.

Neuropeptide Y in the noradrenergic neurones induces obesity and inhibits sympathetic tone in mice

AIM

Neuropeptide Y (NPY) co-localized with noradrenaline in central and sympathetic nervous systems seems to play a role in the control of energy metabolism. In this study, the aim was to elucidate the effects and pathophysiological mechanisms of increased NPY in catecholaminergic neurones on accumulation of body adiposity.

METHODS

Transgenic mice overexpressing NPY under the dopamine-beta-hydroxylase promoter (OE-NPY(DβH) ) and wild-type control mice were followed for body weight gain and body fat content. Food intake, energy expenditure, physical activity, body temperature, serum lipid content and markers of glucose homoeostasis were monitored. Thermogenic and lipolytic responses in adipose tissues, and urine catecholamine and tissue catecholamine synthesizing enzyme levels were analysed as indices of sympathetic tone.

RESULTS

Homozygous OE-NPY(DβH) mice showed significant obesity accompanied with impaired glucose tolerance and insulin resistance. Increased adiposity was explained by neither increased food intake or fat absorption nor by decreased total energy expenditure or physical activity. Adipocyte hypertrophy and decreased circulating lipid levels suggested decreased lipolysis and increased lipid uptake. Brown adipose tissue thermogenic capacity was decreased and brown adipocytes filled with lipids. Enhanced response to adrenergic stimuli, downregulation of catecholamine synthesizing enzyme expressions in the brainstem and lower adrenaline excretion supported the notion of low basal catecholaminergic activity.

CONCLUSION

Increased NPY in catecholaminergic neurones induces obesity that seems to be a result of preferential fat storage. These results support the role of NPY as a direct effector in peripheral tissues and an inhibitor of sympathetic activity in the pathogenesis of obesity.

Urine soluble urokinase-type plasminogen activator receptor levels correlate with proteinuria in Puumala hantavirus infection

OBJECTIVES

Urokinase-type plasminogen activator receptor (uPAR) is upregulated during inflammation and known to bind to β3 -integrins, receptors used by pathogenic hantaviruses to enter endothelial cells. It has been proposed that soluble uPAR (suPAR) is a circulating factor that causes focal segmental glomerulosclerosis and proteinuria by activating β3 -integrin in kidney podocytes. Proteinuria is also a characteristic feature of hantavirus infections. The aim of this study was to evaluate the relation between urine suPAR levels and disease severity in acute Puumala hantavirus (PUUV) infection.

DESIGN

A single-centre, prospective cohort study.

SUBJECTS AND METHODS

Urinary suPAR levels were measured twice during the acute phase and once during convalescence in 36 patients with serologically confirmed PUUV infection. Fractional excretion of suPAR (FE suPAR) and of albumin (FE alb) was calculated.

RESULTS

The FE suPAR was significantly elevated during the acute phase of PUUV infection compared to the convalescent phase (median 3.2%, range 0.8-52.0%, vs. median 1.9%, range 1.0-5.8%, P = 0.005). Maximum FE suPAR was correlated markedly with maximum FE alb (r = 0.812, P < 0.001) and with several other variables that reflect disease severity. There was a positive correlation with the length of hospitalization (r = 0.455, P = 0.009) and maximum plasma creatinine level (r = 0.780, P < 0.001) and an inverse correlation with minimum urinary output (r = -0.411, P = 0.030). There was no correlation between FE suPAR and plasma suPAR (r = 0.180, P = 0.324).

CONCLUSION

Urinary suPAR is markedly increased during acute PUUV infection and is correlated with proteinuria. High urine suPAR level may reflect local production of suPAR in the kidney during the acute infection.

High pentraxin-3 plasma levels associate with thrombocytopenia in acute Puumala hantavirus-induced nephropathia epidemica

Our aim was to investigate whether plasma levels of the long pentraxin-3 (PTX3) associate with the severity of Puumala hantavirus-induced nephropathia epidemica (NE). Sixty-one prospectively identified consecutively hospitalized NE patients were examined. Plasma PTX3, interleukin (IL)-6, terminal complement complex SC5b-9, complement component C3, C-reactive protein (CRP), creatinine, sodium, kynurenine, and tryptophan levels, as well as the blood cell count, were determined for up to five consecutive days after hospitalization. Receiver operating characteristic (ROC) analysis revealed that the maximum PTX3 level >101.6 ng/ml (high PTX3) showed a sensitivity of 71% and a specificity of 89% for detecting platelet level <50 × 10(9)/l, with an area under the curve (AUC) value of 0.78 (95% confidence interval [CI] 0.63-0.94). High PTX3 level was also associated with several other variables reflecting the severity of the disease: patients with high PTX3 level had higher maximum blood leukocyte (16.1 vs. 9.7 × 10(9)/l, p < 0.001), plasma IL-6 (16.9 vs. 9.0 pg/ml, p = 0.007), and creatinine (282 vs. 124 μmol/l, p = 0.007) levels than patients with low maximum PTX3 level. They also had longer hospital stays (8 vs. 5 days, p = 0.015) compared to patients with low PTX3 level. High plasma PTX3 levels are associated with thrombocytopenia and the overall severity of NE.

Hormonal deficiencies during and after Puumala hantavirus infection

Previous reports have described panhypopituitarism associated with severe cases of hemorrhagic fever with renal syndrome (HFRS), but the prevalence of hormonal deficiencies after nephropathia epidemica (NE), a milder form of HFRS, has not been studied. This study was conducted in order to determine the prevalence of hormonal defects in patients with acute NE and during long-term follow-up. Fifty-four patients with serologically confirmed acute NE were examined by serum hormonal measurements during the acute NE, after 3 months, and after 1 to 10 (median 5) years. Thirty out of 54 (56%) patients had abnormalities of the gonadal and/or thyroid axis during the acute NE. After a median follow-up of 5 years, 9 (17%) patients were diagnosed with a chronic, overt hormonal deficit: hypopituitarism was found in five patients and primary hypothyroidism in five patients. In addition, chronic subclinical testicular failure was found in five men. High creatinine levels and inflammatory markers during NE were associated with the acute central hormone deficiencies, but not with the chronic deficiencies. Hormonal defects are common during acute NE and, surprisingly, many patients develop chronic hormonal deficiencies after NE. The occurrence of long-term hormonal defects cannot be predicted by the severity of acute NE.

Detection of human norovirus from frozen raspberries in a cluster of gastroenteritis outbreaks

We describe a cluster of norovirus outbreaks affecting about 200 people in Southern Finland in September and October 2009. All outbreaks occurred after consumption of imported raspberries from the same batch intended for the catering sector. Human norovirus genotype GI.4 was found in frozen raspberries. The berries were served in toppings of cakes in separate catering settings or mixed in curd cheese as a snack for children in a daycare center. The relative risk for consumption of the berry dish was 3.0 (p ≤ 0.05) at the daycare centre. Human norovirus GI.4 was also detected in samples from two patients, and in berries. Both shared identical partial capsid sequences. Based on the results of epidemiological, trace-back and laboratory investigations it was concluded that one particular batch of frozen raspberries was the source of all outbreaks.

A midterm follow-up study of bioreconstructive polylactide scaffold implants in metacarpophalangeal joint arthroplasty in rheumatoid arthritis patients

This paper presents the results of a prospective study of 80 metacarpophalangeal joint arthroplasties, in which biodegradable polylactide 96/4 copolymer scaffolds were used. Twenty-three rheumatoid arthritis patients were assessed at an average of 59 months after operation, which exceeds the resorption time of P(L/D)LA 96/4 according to animal experiments. Palmar subluxation exceeded half of the bone thickness in 39 joints before operation and in nine at the last follow-up. Ulnar deviation decreased from 25 degrees to 5 degrees , extension deficit from 32 degrees to 15 degrees and active flexion from 76 degrees to 63 degrees . The results are comparable with published data on silicone implant arthroplasties. Implant resorption did not induce any significant osteolysis in the medium term and the restoration of the structure and function of the hand was maintained after implant resorption, probably as the guided fibrous tissues had replaced the dissolved implant.

Radiocarpal arthrodesis in the treatment of the rheumatoid wrist. A prospective midterm follow-up

This prospective study was performed to evaluate the clinical and radiological results of radiocarpal joint arthrodesis in the treatment of unstable Simmen group III and Larsen grade II or III rheumatoid wrists. Radiolunate arthrodesis was performed in 16 wrists and radioscapholunate arthrodesis in 7 wrists in 20 patients. When they were evaluated at a mean of 5.8 (range 3.5-9.8) years later, flexion was 29 degrees and extension 34 degrees , representing 67% and 92% of the preoperative values, respectively. Patient satisfaction was excellent, or good, for 20 wrists and satisfactory for 1 wrist. In two patients with poor satisfaction, arthritis progressed to the midcarpal joint and necessitated total arthrodesis of the wrist. Radiolunate joint arthrodesis, with inclusion of the scaphoid in the fusion if necessary, is a useful operation in the treatment of this degree of wrist disease as it produces a functional and pain-free wrist at the same time as preserving much of the mobility and bone stock.

Mutational analysis of the human SLC26A8 gene: exclusion as a candidate for male infertility due to primary spermatogenic failure

SLC26A8 is an anion transporter that is solely expressed in the testes. It interacts with MgcRacGAP that shows strong structural similarity with the Drosophila protein RotundRacGAP, which is established to have an essential role for male fertility in the fruit fly. To explore whether the SLC26A8 gene has a role in human male infertility, we performed mutational analysis in the coding region of the SLC26A8 gene in 83 male infertility patients and two groups of controls using single-strand conformational polymorphism and direct sequencing methods. We found six novel coding sequence variations, of which five lead to amino acid substitutions. All variants were found with similar frequencies in both patients and controls, thus suggesting that none of them may be causally associated with infertility. We conclude that the SLC26A8 mutations are not a common cause of male infertility.

Bioreconstructive joint scaffold implant arthroplasty in metacarpophalangeal joints: short-term results of a new treatment concept in rheumatoid arthritis patients

Swanson silicone implant is the "gold standard" of metacarpophalangeal joint reconstruction in rheumatoid arthritis (RA) patients. However, durability problems of silicone implants have led us to develop a new technique based on bioreconstructive implants. PLA96 (poly-L,D-lactide copolymer, L:D ratio of 96:4) scaffolds were engineered. Bioabsorption and substitution of porous PLA96 scaffold with living tissue eventually produce a neojoint. In the current prospective study, 23 RA patients (80 joints) were operated on, using PLA96 implants. Fifteen patients (54 joints) have been monitored for at least 1 year. Pain alleviation was well achieved. Range of motion improvement was emphasized to extension direction of functional arc. The average ulnar deviation was preoperatively 26 degrees, and at follow-up it was 6 degrees. Volar subluxation was noticeable in 56% of joints preoperatively and in 6% at 1-year follow-up. This is the first report of the formation of a living, functional joint in situ by means of a synthetic bioreconstructive joint scaffold. Results of this preliminary short-term study are comparable with previously published data on silicone arthroplasty. However, bioreconstructive prostheses can aid in preventing problems that occur with biostable prostheses. Tissue engineering has created a new era in the reconstruction of damaged joints.

Estrogen receptor-beta is the predominant estrogen receptor subtype in human oral epithelium and salivary glands

Many studies have shown that the oral mucosa and salivary glands are sensitive to estrogen action. However, the expression of estrogen receptors (ERs) within these tissues is an area of controversy. ERs exist as two subtypes (ERalpha and ERbeta), and we hypothesized that the incongruity between ER expression and estrogen sensitivity may result from differential expression of ER subtypes in oral tissues. To test this hypothesis, we analyzed oral mucosal and salivary gland samples for ERalpha and ERbeta protein expression by immunohistochemistry from a cross-section of patients attending hospital for surgical problems of the head and neck. ERalpha was not detected in oral buccal and gingival epithelium or in salivary glands. In contrast, ERbeta was widely expressed at high levels in all oral tissues studied. Within these tissues, ERbeta was observed primarily in keratinocytes and salivary gland acinar and ductal cells. Our results demonstrating the expression of only the ERbeta subtype within oral tissues may explain the contradictory results from previous studies investigating ER expression in these tissues. Importantly, these results suggest that estrogens may act via ERbeta in oral tissues and explain the effect of hormonal changes on the oral mucosa as well as on saliva secretion and composition.

Upregulation of CFTR expression but not SLC26A3 and SLC9A3 in ulcerative colitis

In inflamed colonic mucosa, the equilibrium between absorptive and secretory functions for electrolyte and salt transport is disturbed. We compared the expression of three major mediators of the intestinal salt transport between healthy and inflamed colonic mucosa to understand the pathophysiology of diarrhea in inflammatory bowel disease. Expression levels of the cystic fibrosis transmembrane regulator (CFTR) (Cl- channel), SLC26A3 (Cl-/HCO exchanger) and SLC9A3 (Na+/H+ exchanger) mRNAs were measured by real-time quantitative RT-PCR in peroperative colonic samples from controls (n = 4) and patients with ulcerative colitis (n = 10). Several samples were obtained from each individual. Tissue samples were divided into three subgroups according to their histological degree of inflammation. Expression of CFTR and SLC26A3 proteins were determined by immunohistochemistry and Western blotting from the same samples, respectively. Increased expression of CFTR mRNA was observed in all three groups of affected tissue samples, most pronounced in mildly inflamed colonic mucosa (5-fold increase in expression; P < 0.001). The expression of the CFTR protein was detected from health and inflamed colon tissue. Although the expression of the SLC26A3 mRNA was significantly decreased in severe ulcerative colitis (P < 0.05), the SLC26A3 protein levels remained unchanged in all groups. The expression of SLC9A3 mRNA was significantly changed between the mild and severe groups. Intestinal inflammation modulates the expression of three major mediators of intestinal salt transport and may contribute to diarrhea in ulcerative colitis both by increasing transepithelial Cl- secretion and by inhibiting the epithelial NaCl absorption.

Estrogen receptors and proliferation markers in primary and recurrent breast cancer

To elucidate the clinical importance of estrogen receptor (ER) beta in breast cancer, 29 archival primary breast cancer specimens, six locally recurrent cancers, and five benign mammary tumors were examined histochemically for ERalpha, ERbeta and the proliferation markers Ki67 and cyclin A. In benign tumors, most epithelial cells contained ERbeta, but ERalpha was rare. In primary cancers, both ERalpha and ERbeta occurred in epithelial cells, the presence of ERbeta being associated with elevated expression of Ki67 and cyclin A, and ERalpha with decreased levels. Thus, the highest content of proliferation markers was seen in primary cancers that were ERalpha(-) ERbeta(+). Most Ki67-containing cells coexpressed ERbeta, but few showed ERalpha. In locally recurring cancers, ERalpha, ERbeta, and Ki67 were more highly expressed than in the corresponding primary tumors, and many cells containing ERbeta, but few with ERalpha, expressed Ki67. Surprisingly, ERbeta, but not ERalpha, was seen in the stromal cells of both primary and recurrent cancers. Because the response of breast cancers to tamoxifen therapy is correlated with the presence of ERalpha, cancer cells that lack ERalpha but contain ERbeta and proliferation markers represent a novel population of apparently proliferating cells that probably are not targeted by the current antiestrogens. Thus, appropriate ERbeta-specific ligands, perhaps in combination with tamoxifen, may be useful in improving the treatment of breast cancers.

Mesangiocapillary glomerulonephritis caused by Puumala hantavirus infection

Nephropathia epidemica induced by Puumala hantavirus typically causes acute reversible renal function impairment. A typical renal biopsy finding is acute tubulointerstitial nephritis with slight glomerular mesangial changes. We describe here 5 patients who developed the nephrotic syndrome during the convalescent phase of an otherwise typical acute febrile nephropathia epidemica. Renal biopsy of all patients disclosed type I mesangiocapillary glomerulonephritis (MCGN). A clinical remission of the nephrotic syndrome was observed in 4 patients during the follow-up period, and 1 entered into chronic renal failure. Three patients had microscopic hematuria and proteinuria and 2 elevated blood pressure at the latest assessment visit. No patient had clinical or laboratory findings compatible with chronic bacterial, parasitic or viral infections (hepatitis B or C), malignancies, or other disorders known to be associated with MCGN. In conclusion, Puumala hantavirus has to be added to the list of potential agents associated with type I MCGN. Further studies are necessary to establish the incidence of MCGN caused by various hantavirus infections.

Mechanisms of estrogen action

Our appreciation of the physiological functions of estrogens and the mechanisms through which estrogens bring about these functions has changed during the past decade. Just as transgenic mice were produced in which estrogen receptors had been inactivated and we thought that we were about to understand the role of estrogen receptors in physiology and pathology, it was found that there was not one but two distinct and functional estrogen receptors, now called ER alpha and ER beta. Transgenic mice in which each of the receptors or both the receptors are inactive have revealed a much broader role for estrogens in the body than was previously thought. This decade also saw the description of a male patient who had no functional ER alpha and whose continued bone growth clearly revealed an important function of estrogen in men. The importance of estrogen in both males and females was also demonstrated in the laboratory in transgenic mice in which the aromatase gene was inactivated. Finally, crystal structures of the estrogen receptors with agonists and antagonists have revealed much about how ligand binding influences receptor conformation and how this conformation influences interaction of the receptor with coactivators or corepressors and hence determines cellular response to ligands.

No evidence for the in vivo activity of aromatase-inhibiting flavonoids

Measurements of the aromatase-inhibiting and antioxidative capacities of flavonoids in vitro showed that slight changes in flavonoid structure may result in marked changes in biological activity. Several flavonoids such as 7-hydroxyflavone and chrysin (5,7-dihydroxyflavone) were shown to inhibit the formation of 3H-17beta-estradiol from 3H-androstenedione (IC(50)<1.0 microM) in human choriocarcinoma JEG-3 cells and in human embryonic kidney cells HEK 293 transfected with human aromatase gene (Arom+HEK 293). Flavone and quercetin (3,3',4',5,7-pentahydroxyflavone) showed no inhibition (IC(50)>100 microM). None of the requirements for optimal antioxidative capacity (2,3-double bond with 4'-hydroxy group, 3-hydroxyl group, 5,7-dihydroxy structure and the orthodihydroxy structure in the B-ring) is relevant for the maximum inhibition of aromatase by flavonoids. After oral administration to immature rats at a dose of 50 mg/kg body weight, which considerably exceeds amounts found in daily human diets, neither aromatase-inhibiting nonestrogenic flavonoids, such as chrysin, nor estrogenic flavonoids, such as naringenin and apigenin, induced uterine growth or reduced estrogen- or androgen-induced uterine growth. The inability of flavonoids to inhibit aromatase and, consequently, uterine growth in short-term tests may be due to their relatively poor absorption and/or bioavailability.

Co-localization of androgen receptor with estrogen receptor beta in the lower urinary tract of the male rat

PURPOSE

Androgens and estrogens influence voiding. In this study their target sites in the lower urinary tract of the male rat were identified.

MATERIALS AND METHODS

Cryosections of the bladder body, bladder neck, prostatic urethra, mid proximal urethra and prostatic autonomic ganglia of adult male rats were immunostained with specific estrogen receptor alpha, estrogen receptor beta (ERbeta) or androgen receptor (AR) antibodies. The sections were then examined under conventional, fluorescence or confocal fluorescence microscopy.

RESULTS

Co-expression of AR and ERbeta in the urothelium, bladder smooth muscle cells, proximal urethra striated muscle cells and neurons in the autonomic ganglia of the prostatic plexus suggests that estrogen and androgen have direct effects in the lower urinary tract.

CONCLUSIONS

The local interaction of AR and ERbeta in the hormonal control of voiding is an intriguing possibility.

Polymorphism of the cytokine genes in hospitalized patients with Puumala hantavirus infection

BACKGROUND

Nephropathia epidemica (NE) is a mild type of haemorrhagic fever with renal syndrome caused by Puumala (PUU) hantavirus. The clinical course of NE varies from asymptomatic to fatal. The aim of this study was to establish whether polymorphisms in the cytokine genes are associated with susceptibility to and outcome of NE.

METHODS

The genotypes of the genes of tumour necrosis factor alpha (TNFalpha), interleukin-1alpha (IL-1alpha), IL-1beta and IL-1 receptor antagonist (IL-1RA) were analysed by polymerase chain reaction in 87 subjects, all hospital-treated for serologically confirmed acute NE. The control group comprised 400 healthy blood donors. Nineteen out of these 400 (5%) controls were PUU virus-seropositive.

RESULTS

IL-1RA allele 2 and IL-1beta (base exchange polymorphism at position -511) allele 2 were strongly associated with each other in both groups. NE patients were more often IL-1RA-2 negative/IL-1beta-2 negative than PUU-seronegative blood donors (38 vs 27%, odds ratio 1.65, 95% confidence interval 1.0-2.7). However, there were no differences in the clinical severity of NE between the IL-1RA-2 negative/IL-1beta-2 negative and the other patients. The other allele frequencies studied evinced no statistically significant differences between the groups. Thirty-three out of 87 (38%) patients and 121 out of 381 (32%) seronegative controls were carriers of the high-producer genotype TNF2 allele. Several parameters showed the clinical course of NE to be more severe in TNF2 carriers than in non-carriers.

CONCLUSIONS

These data suggest that non-carriage of the IL-1RA allele 2 and IL-1beta (-511) allele 2 may contribute to susceptibility to NE. Furthermore, TNFalpha polymorphism seems to be associated with the outcome of NE.

Localization of oestrogen receptors alpha and beta in human testis

Cellular localization of oestrogen receptor alpha (ERalpha) and beta (ERbeta) proteins were studied in human testis samples using immunohistochemistry, and the expression of the corresponding mRNA was examined with reverse transcription-polymerase chain reaction (RT-PCR). Seven men, aged 28-48 years, who underwent diagnostic testicular biopsy because of azoospermia or to give spermatozoa for intracytoplasmic injection for infertility treatment, donated tissue for the study. One of them had anejaculation but normally functioning testes, and one was diagnosed as having Sertoli cell-only syndrome (SCOS). In addition, expression of ERbeta protein was examined in one testis sample obtained from a man undergoing a sex change operation. Strong ERbeta immunoreactivity was detected in the nuclei of spermatogonia, spermatocytes and early developing spermatids. Elongating spermatids, mature spermatozoa, Sertoli and Leydig cells were all negative for ERbeta. The presence of ERbeta protein was confirmed in Western analysis. With RT-PCR, both wild-type ERbeta and ERbetacx, the isoform which represses wild-type ER function, were easily detected. In most cases, ERbetacx mRNA was more abundantly expressed than wild-type ERbeta. The patient with SCOS expressed neither ERbeta isoform. Neither ERalpha protein nor ERalpha mRNA was detected in any of the samples. We conclude that in the human testis, ERbeta is likely to be the ER that mediates the effects of oestrogen.

Altered structure and function of reproductive organs in transgenic male mice overexpressing human aromatase

Aromatization of androgens is a key step in estrogen production, and it regulates the delicate balance between estrogens and androgens in the gonads and sex steroid target tissues. In the present study, we generated transgenic mice (AROM(+)) bearing the human ubiquitin C promoter/human P450 aromatase fusion gene. AROM(+) male mice are characterized by an imbalance in sex hormone metabolism, resulting in elevated serum E(2) concentrations, combined with significantly reduced testosterone and FSH levels, and elevated levels of PRL and corticosterone. AROM(+) males present a multitude of severe structural and functional alterations in the reproductive organs, such as cryptorchidism associated with Leydig cell hyperplasia, dysmorphic seminiferous tubules, and disrupted spermatogenesis. The males also have small or rudimentary accessory sex glands with abnormal morphology; a prominent prostatic utricle with squamous epithelial metaplasia, and edema in the ejaculatory ducts and vas deferens. In addition, the abdominal muscle wall is thin, and the adrenal glands are enlarged, with cortical hyperplasia. Some of the abnormalities, such as undescended testes and undeveloped prostate, resemble those observed in animals exposed perinatally to high levels of exogenous estrogen, indicating that the elevated aromatase activity results in excessive estrogen exposure during early phases of development. Some of the disorders in the reproductive organs, furthermore, can be explained by the fact that AROM(+) males are hypoandrogenic, and have elevated levels of serum PRL and corticosterone. Thus, the AROM(+) mouse model provides a novel tool to investigate the consequences of a prolonged increase in conversion of androgens to estrogens which results in complex hormonal disturbances altering the structure and function of various male reproductive organs.

Nontraumatic urethral dyssynergia in neonatally estrogenized male rats

PURPOSE

Bladder outlet obstruction develops in estrogen treated males. Because of the lack of electromyography recordings, earlier studies have not clarified the failure mechanisms of voiding. We simultaneously recorded electromyography activity of the proximal rhabdosphincter in neonatally estrogenized rats with transvesical cystometry and urethral flow, followed by morphometric analysis of the urethral structure.

MATERIALS AND METHODS

Rats treated neonatally with 10 microg. diethylstilbestrol daily on days 1 to 5 after birth were used in urodynamics and morphological studies at ages 5 to 6.5 months. Using anesthesia the bladder, anterior surface of the proximal rhabdosphincter and distal urethra were exposed to record simultaneously the high frequency oscillations of intraluminal bladder pressure, and the rates of intermittent flow from the distal urethra and electromyography activity of the proximal rhabdosphincter with a suction electrode.

RESULTS

Neonatally estrogenized rats had higher mean maximal bladder pressure plus or minus standard deviation (42.1 +/- 6.4 versus 37.7 +/- 4.9 mm. Hg, p = 0.01), decreased mean flow (2.3 +/- 0.1 versus 4.1 +/- 1.6 ml. per minute, p < 0.0001) and mean increment of proximal rhabdosphincter electromyography depolarization amplitude (3.0 +/- 0.78 versus 2.6 +/- 0.87 mV., p = 0.02) compared with controls, while mean transient repolarization was absent or highly decreased (-0.3 +/- 0.61 versus 0.3 +/- 0.9 mV., p = 0.04). Morphologically the proximal rhabdosphincter was atrophied with increased connective tissue.

CONCLUSIONS

Alterations in the structure and electromyography activity of the urethral musculature imply that neonatal exposure to diethylstilbestrol predisposes male rats to urethral atrophy and dyssynergia, evident as altered electromyography activity of the proximal rhabdosphincter.

Decreased expression of estrogen receptor beta protein in proliferative preinvasive mammary tumors

To understand the significance of estrogen receptor beta (ERbeta) in mammary carcinogenesis, we evaluated the expression of ERbeta in preinvasive mammary tumors. The percentage of ERbeta-positive epithelial or tumoral cells was assayed by quantitative immunohistochemistry using an image analyzer in 130 lesions of varying histological risk from 118 patients [71 with benign breast disease (BBD) and 59 with carcinoma in situ (CIS)] and compared with 118 adjacent histologically normal glands. Five groups of lesions with an increasing risk of invasive cancer, from BBD without hyperplasia to high-grade CIS, were studied. Results were compared with ERalpha and Ki67 immunostaining. The percentage of ERbeta-positive cells was high (median, 85%) in "normal" mammary glands and in nonproliferative BBD and decreased significantly (P < 0.0001) in proliferative BBD without atypia and in CIS, contrasting with an inverse progression for the ERalpha level. In normal mammary glands, the ERbeta level did not vary according to the nature of the lesion at the periphery and was significantly higher (P < 0.007) than in adjacent preinvasive lesions, except in nonproliferative BBD. The ERbeta level decreased in proliferative BBD, anticipating the ERalpha increase, which was significant in BBD with atypia. In high-grade ductal carcinoma in situ, both ER levels were low. The ratio between ERbeta and ERalpha was high in normal glands, and decreased significantly in proliferative lesions. ERbeta staining was inversely correlated with Ki67 (r = -0.333; P < 0.001), more particularly in high-grade ductal carcinoma in situ (r = -0.57; P < 0.02). The marked and early decreased level of ERbeta protein associated with other criteria of cell proliferation suggests a protective effect of ERbeta against the mitogenic activity of estrogens in mammary premalignant lesions. Knowledge of the ERbeta and ERalpha content in each preinvasive lesion should help to rationalize antiestrogen preventive therapy adapted to each individual patient.

Pronounced monocytosis in a case of nephropathia epidemica

Nephropathia epidemica is a mild form of haemorrhagic fever with renal syndrome. Thrombocytopenia is common and characteristic. We report here a case of a young man with nephropathia epidemica and marked transient monocytosis.

Regulation of progesterone receptors and decidualization in uterine stroma of the estrogen receptor-alpha knockout mouse

Regulation of progesterone receptor (PR) in uterine stroma (endometrial stroma plus myometrium) by estrogen was investigated in estrogen receptor-alpha (ERalpha) knockout (alphaERKO) mice. 17 beta-Estradiol (E(2)) increased PR levels in uterine stroma of ovariectomized alphaERKO mice, and ICI 182 780 (ICI) inhibited this E(2)-induced PR expression. Estrogen receptor-beta(ER beta) was detected in both uterine epithelium and stroma of wild-type and alphaERKO mice by immunohistochemistry. In organ cultures of alphaERKO uterus, both E(2) and diethylstilbestrol induced stromal PR, and ICI inhibited this induction. These findings suggest that estrogen induces stromal PR via ERbeta in alphaERKO uterus. However, this process is not mediated exclusively by ERbeta+, because in ERbeta knockout mice, which express ERalpha, PR was up-regulated by E(2) in uterine stroma. In both wild-type and alphaERKO mice, progesterone and mechanical traumatization were essential and sufficient to induce decidual cells, even though E(2) and ERalpha were also required for increase in uterine weight. Progesterone receptor was strongly expressed in decidual cells in alphaERKO mice, and ICI did not inhibit decidualization or PR expression. This study suggests that up-regulation of PR in endometrial stroma is mediated through at least three mechanisms: 1) classical estrogen signaling through ERalpha, 2) estrogen signaling through ERbeta, and 3) as a result of mechanical stimulation plus progesterone, which induces stromal cells to differentiate into decidual cells. Each of these pathways can function independently of the others.

Differential expression of estrogen receptors alpha and beta in adult rat accessory sex glands and lower urinary tract

Estrogens induce pronounced structural and functional changes in male accessory sex glands and the lower urinary tract in both sexes, but the exact mechanisms of estrogen action are not fully understood. This study was undertaken to localise the tissue cell types that express estrogen receptor in adult rats, and to determine the receptor subtype (ERalpha and ERbeta) in order to identify sites that may respond directly to estrogens. In the male accessory sex glands (seminal vesicles, prostatic lobes and ampullary glands), ERbeta mRNA and protein were strongly expressed in the epithelium but not in the stroma, while ERalpha mRNA was present only in the fibromuscular tissue surrounding the prostatic collecting ducts in the posterior periurethral region and in ampullary gland stroma. In the epithelium of the urinary bladder and urethra of both sexes, high level of ERbeta mRNA and protein, but no ERalpha mRNA, was detected. The connective tissue in urinary bladder of both males and females, as well as that in prostatic urethra in males expressed ERalpha mRNA. The neural cells in the autonomic ganglia of the prostatic plexus were strongly positive for ERbeta mRNA, but were completely devoid of ERalpha. We conclude that ERbeta is the predominant ER subtype in the epithelium of adult male rat accessory sex glands and the lower urinary tract of both males and females, as well as in the prostatic neural plexus regulating the function of the lower urinary tract in males, while ERalpha is present only in the stromal compartment of distinct sites. These results indicate that in these tissues in intact adults there are multiple targets for direct estrogen action. Furthermore, the differential or complementary expression of the two ER subtypes suggests that they may have specific functions, and may explain the complex structural and functional changes induced by estrogens.

Renal function and blood pressure five years after puumala virus-induced nephropathy

BACKGROUND

Nephropathia epidemica (NE) is a mild form of hemorrhagic fever with renal syndrome caused by Puumala hantavirus. Its long-term prognosis is considered favorable. Some reports suggest, however, that a previous hantavirus infection increases the risk of hypertension.

METHODS

We studied 46 previously healthy subjects (26 males and 20 females, mean age of 44 years) who had serologically confirmed NE three to seven years previously, and 38 healthy, seronegative controls (22 males and 16 females, mean age of 44 years). Ambulatory blood pressure (ABP) was monitored. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were determined by 51CrEDTA and 131I-hippurate clearances, respectively. The filtration fraction (FF) was calculated. Quantitative 24-hour urinary protein excretion (UprotE) and timed overnight urinary excretion of alpha1-microglobulin were measured.

RESULTS

The NE patients had a higher mean ambulatory systolic BP than the controls (123 +/- 13 vs. 117 +/- 9 mm Hg, P = 0. 008). GFR and FF were increased in patients compared with controls (GFR, 120 +/- 20 vs. 109 +/- 14 mL/min/1.73 m2, P = 0.006; FF, 19 +/- 3 vs. 18 +/- 3%, P = 0.030), but ERPF did not differ between the groups. The patients also had higher UPE than the controls (median 0. 18 g/day, range 0.12 to 0.38 vs. median 0.14 g/day, range 0.09 to 0. 24, P < 0.001, respectively). The overnight urinary excretion rate of alpha1-microglobulin exceeded 7 microg/min in nine patients.

CONCLUSION

Three to seven years after NE, the patients had higher GFR and FF, more proteinuria, and higher ambulatory systolic BP compared with the healthy controls. NE may thus cause mild renal lesions and alterations in BP in some patients.

Regulation of vascular endothelial growth factor expression by estrogens and progestins

Estrogens increase the expression of vascular endothelial growth factor (VEGF) mRNA in the rodent uterus. This regulatory effect is rapid, beginning within 1 hr after hormone treatment, dose dependent, and blocked by the pure antiestrogen ICI 182,780. The induction of the transcript is blocked by inhibitors of RNA but not of protein synthesis, and we have recently identified estrogen response elements in the VEGF gene. Collectively, these findings indicate that estrogens regulate uterine VEGF expression at the transcriptional level via the classical nuclear estrogen receptor pathway. Estrogen induction of VEGF occurs in the stromal layer of the rodent uterus, and estradiol induces expression of VEGF transcript levels in cultured human uterine stromal cells. Progestins also induce VEGF expression in the rodent uterus, although the effect is less marked and slower in onset than estrogenic effects. The effect of progestins is blocked by the antiprogestin mifepristone (RU-486), suggesting that it is also mediated by a classical nuclear receptor pathway. In addition, progestins regulate expression of VEGF mRNA and protein in cultured human T47-D breast cancer cells. The development of uterine leiomyomas is associated with exposure to ovarian sex steroids, abnormal uterine bleeding is commonly seen in patients with leiomyomas, and fibroids require an increased vascular supply for their growth. These observations suggest that VEGF and other angiogenic factors may represent potential targets for the treatment and prevention of uterine fibroids.

Differential expression of estrogen receptors alpha and beta in adult rat accessory sex glands and lower urinary tract

Estrogens induce pronounced structural and functional changes in male accessory sex glands and the lower urinary tract in both sexes, but the exact mechanisms of estrogen action are not fully understood. This study was undertaken to localise the tissue cell types that express estrogen receptor in adult rats, and to determine the receptor subtype (ER alpha and ER beta) in order to identify sites that may respond directly to estrogens. In the male accessory sex glands (seminal vesicles, prostatic lobes and ampullary glands), ER beta mRNA and protein were strongly expressed in the epithelium but not in the stroma, while ER alpha mRNA was present only in the fibromuscular tissue surrounding the prostatic collecting ducts in the posterior periurethral region and in ampullary gland stroma. In the epithelium of the urinary bladder and urethra of both sexes, high level of ER beta mRNA and protein, but no ER alpha mRNA, was detected. The connective tissue in urinary bladder of both males and females, as well as that in prostatic urethra in males expressed ER alpha mRNA. The neural cells in the autonomic ganglia of the prostatic plexus were strongly positive for ER beta mRNA, but were completely devoid of ER alpha. We conclude that ER beta is the predominant ER subtype in the epithelium of adult male rat accessory sex glands and the lower urinary tract of both males and females, as well as in the prostatic neural plexus regulating the function of the lower urinary tract in males, while ER alpha is present only in the stromal compartment of distinct sites. These results indicate that in these tissues in intact adults there are multiple targets for direct estrogen action. Furthermore, the differential or complementary expression of the two ER subtypes suggests that they may have specific functions, and may explain the complex structural and functional changes induced by estrogens.

Distribution of collagen XII and XIV in the bladder wall of the male rat with outlet obstruction

PURPOSE

Our previous studies indicate that neonatal estrogenization with diethylstilbestrol (neoDES) of male mice and rats causes partial outlet obstruction. In the present study, type XII and XIV collagens were localized in the bladder to study their role in the development of obstruction.

MATERIALS AND METHODS

The bladder sections immunostained with smooth muscle specific a-actin antibody were double labeled either with collagen type XII or type XIV antibodies. The specimens were then analyzed with conventional and confocal fluorescence microscope.

RESULTS

Type XII and XIV collagens were not evenly distributed in the bladder. Further, in neonatally estrogenized rats collagen XIV appeared inside smooth muscle fascicles.

CONCLUSIONS

Non-overlapping distributions of collagen XII and XIV suggest their different roles in the urinary bladder. Penetration of collagen XIV inside smooth muscle fascicles may have a role in the development of DES-induced partial outlet obstruction.

Differentiation between vasculoprotective and uterotrophic effects of ligands with different binding affinities to estrogen receptors alpha and beta

Estrogen-based drug therapy in cardiovascular diseases has been difficult because it has not been possible to separate the wanted vasculoprotective effect from the unwanted effects of the hormone to the reproductive system. Here, we demonstrate that, after endothelial denudation of rat carotid artery, the mRNA of the classical estrogen receptor (ERalpha) is constitutively expressed at a low level whereas the expression of the novel ERbeta mRNA increases >40-fold. Under in situ hybridization and immunohistochemistry, ERbeta mRNA and protein colocalize with the smooth muscle cells in the media and neointima. Treatment of ovariectomized female rats with the isoflavone phytoestrogen genistein, which shows 20-fold higher binding affinity to ERbeta than to ERalpha, or with 17beta-estradiol, which does not differentiate between the two receptors, provides similar dose-dependent vasculoprotective effect in rat carotid injury model. In addition in concentrations <10 microM, both ligands are equally inhibitory to the replication and migration of smooth muscle cells in vitro. However, only treatment with 17beta-estradiol, but not with genistein, is accompanied with a dose-dependent uterotrophic effect. The results suggest that preferential targeting to ERbeta will provide vasculoprotective estrogen analogs devoid of effects to the reproductive system.

Dietary phytoestrogens and their role in hormonally dependent disease

Epidemiological studies suggest that diets rich in phytoestrogens (plant estrogens), particularly soy and unrefined grain products, may be associated with low risk of breast and prostate cancer. It has also been proposed that dietary phytoestrogens could play a role in the prevention of other estrogen-related conditions, namely cardiovascular disease, menopausal symptoms and post-menopausal osteoporosis. However, there is no direct evidence for the beneficial effects of phytoestrogens in humans. All information is based on consumption of phytoestrogen-rich diets, and the causal relationship and the mechanisms of phytoestrogen action in humans still remain to be demonstrated. In addition, the possible adverse effects of phytoestrogens have not been evaluated. It is plausible that phytoestrogens, as any exogenous hormonally active agent, might also cause adverse effects in the endocrine system, i.e. act as endocrine disrupters.

Genistein exerts estrogen-like effects in male mouse reproductive tract

The aim of this study was to evaluate the estrogenicity of genistein in the neonatal and adult male mouse reproductive tract. In intact adults, genistein (2.5 mg s.c./kg of body weight/day for 9 days) reduced testicular and serum testosterone concentrations, pituitary LH-content and prostate weight. In castrated adults, genistein (0.025-2.5 mg s.c./kg of body weight) increased expression of c-fos gene in prostatic urethra. In adult, neonatally estrogenized mice showing an increased estrogen sensitivity, a 10-day treatment with genistein (2.5 mg s.c./kg of body weight) induced development of squamous epithelial metaplasia in prostatic collecting ducts. Neonatally, only a very high dose of genistein (1 mg/pup per day; i.e. approximately 500 mg/kg of body weight) induced persistent structural changes, similar to those seen in mice treated neonatally with diethylstilbestrol, in the urethroprostatic complex. These results suggest that in adult males, genistein induces the typical estrogenic effects in doses comparable to those present in soy-based diets, while in neonatal animals, considerably higher doses are required to show estrogen-like activity.

A case of a laboratory animal feed with high estrogenic activity and its impact on in vivo responses to exogenously administered estrogens

We recently noted that immature rats failed to exhibit a normal uterine response to exogenously administered estradiol as assessed by both biochemical (induction of gene expression) and morphological (altered uterine and vaginal histology and size) end points. An initial analysis suggested that this was due to a high degree of estrogenization from a dietary source which was producing a near maximal uterotrophic response prior to hormone treatment. Subsequent chemical analysis indicated that the feed in question contained high amounts of two well-known phytoestrogens, genistein (210 mg/kg) and daidzen (14 mg/kg), and the lot of feed in question produced a large uterotrophic effect when fed to immature ovariectomized rats. These findings illustrate that, despite increased awareness of phytoestrogens, some batches of animal feed contain very high amounts of estrogenic components which have marked effects on in vivo end points of hormone action. These observations have important implications for both basic research and screening methods that utilize in vivo approaches.

Inhibition of 17beta-hydroxysteroid oxidoreductase by flavonoids in breast and prostate cancer cells

Several flavonoids and isoflavonoids were found to inhibit 17beta-oxidoreduction of estrogens by the purified 17beta-HSOR type 1, or in cell lines expressing 17beta-HSOR type 1 enzyme (T-47D breast cancer cells) or type 2 (PC-3 prostate cancer cells). The structural demands for the inhibition of estrone (E1) reduction and estradiol (E2) oxidation catalyzed by 17beta-HSOR types 1 and 2, respectively, were not identical. Flavones, flavanones, and isoflavones hydroxylated at both the double ring (positions 5 and 7) and ring B (position 4') were the most potent inhibitors of E1 reduction in T-47D cells, and by the purified type 1 enzyme whereas flavones hydroxylated at positions 3, 5, and 7 of rings A and C, with or without a hydroxyl group in ring B, were capable of inhibiting E2 oxidation in PC-3 cells. Change to flavanone structure, or hydroxylation at position 3 of ring C of flavones, or methylation of the hydroxyl group at position 4' of ring B of flavones and isoflavones reduced or abolished their inhibitory activity on E1 reduction in T-47D cells. On the contrary, hydroxyl group at position 3 of flavones (flavonol structure) markedly increased the inhibition of E2 oxidation in PC-3 cells. Thus, changes in the number and location of hydroxyl groups may discriminate inhibition of E1 reduction and E2 oxidation. Some of the differences may be due to differences in pharmacokinetics of these compounds in T-47D and PC-3 cells. Inhibition of 17beta-HSORs could lead to an alteration in the availability of the highly active endogenous estrogen, but the effects of these compounds in vivo cannot be predicted on the basis of these results alone. Some of these compounds (isoflavones) are estrogenic per se, and they may replace endogenous estrogens, whereas flavones are only very weakly estrogenic or nonestrogenic. Regarding prevention or treatment of estrogen-related diseases, apigenin, coumestrol, and genistein raise special interest.

Phytoestrogens: potential endocrine disruptors in males

Exposure to diethylstilbestrol (DES) induces persistent structural and functional alterations in the developing reproductive tract of males. It is possible that xenoestrogens other than DES alter sexual differentiation in males and account for the increasing incidence of developmental disorders of the reproductive tract in men and wild animals. Phytoestrogens (coumestans, isoflavonoids, flavonoids, and lignans) present in numerous edible plants are quantitatively the most important environmental estrogens when their hormonal potency is assessed in vitro. They exert their estrogenic activity by interacting with estrogen receptors (ERs) in vitro. They may also act as antiestrogens by competing for the binding sites of estrogen receptors or the active site of the estrogen biosynthesizing and metabolizing enzymes, such as aromatase and estrogen-specific 17 beta-hydroxysteroid oxidoreductase (type 1). In theory, phytoestrogens and structurally related compounds could harm the reproductive health of males also by acting as antiestrogens. There are very little data on effects of phytoestrogens in males. Estrogenic effects in wildlife have been described but the evidence for the role of phytoestrogens is indirect and seen under conditions of excessive exposure. In doses comparable to the daily intake from soybased feed, isoflavonoids such as genistein were estrogen agonists in the prostate of adult laboratory rodents. When given neonatally, no persistent effects were observed. In contrast, the central nervous system (CNS)-gonadal axis and the male sexual behavior of the rat appear to be sensitive to phytoestrogens during development. The changes were similar but not identical to those seen after neonatal treatment with DES, but higher doses of phytoestrogens were needed.

Neonatal estrogenization of the male mouse results in urethral dysfunction

PURPOSE

Analysis of voiding pattern, urodynamic measurements and immunohistochemical methods were performed in order to evaluate the effects of neonatal estrogenization on voiding functions of adult male mice.

MATERIALS AND METHODS

Metabolic cages were used for recording the voiding volumes and frequencies. Bladder pressure and mean flow during voiding were measured in transvesical cystometry. Location of estrogen receptors and organization of smooth muscles in lower urinary track were demonstrated using immunohistochemical staining.

RESULTS

Neonatally estrogenized (neoDES) male mice had lower voided urine volumes (the average voided urine volume and average of the three largest volumes) and higher voiding frequencies than control mice. In transvesical cystometry, the maximum bladder pressure during the high-frequency oscillation phase of voiding was significantly elevated. The average urinary flow rate was decreased.

CONCLUSIONS

Urodynamically, these findings are consistent with the concept that neonatally estrogenized mice have infravesical obstruction. The predominance of estrogen receptors in the periurethral region and changes in urethral smooth muscle cells immunocytochemically stained with alpha-actin-antibody support the concept of urethral wall musculature as a target of estrogen action.

Wood-derived estrogens: studies in vitro with breast cancer cell lines and in vivo in trout

The wood-derived compound, beta-sitosterol (purity > 90%), was shown to be estrogenic in fish. It induced the expression of the vitellogenin gene in the liver of juvenile and methyltestosterone-treated rainbow trout. Structural similarities to beta-sitosterol notwithstanding, cholesterol, citrostadienol, beta-sitostanol, and 5-androstene-3 beta,17 beta-diol, an estrogenic member of the androstenic steroid group, were inactive. An abietic acid mixture (37% abietic acid, 6% dehydroabietic acid, and a remainder of unknown compounds) showed slight hormonal activity in feed, but it was completely inactive when given intraperitoneally in implants. The estrogenic component of the abietic acid preparation was not identified. In addition, to beta-sitosterol and abietic acid, several other wood-derived compounds including betulin, isorhapontigenin, isorhapontin, and pinosylvin were estrogenic in breast cancer cells (MCF-7 or T-47D). However, betulin and pinosylvin, available in sufficient amounts for in vivo testing, did not induce the expression of the vitellogenin gene. Differences in the primary sequences of human and fish estrogen receptors (hormone as well as DNA-binding regions) or uptake and metabolism of the compounds may explain the discrepancy between the two estrogen bioassays. Wood-derived compounds such as beta-sitosterol, present in pulp and paper mill effluents, may account for the weak estrogenicity of debarking effluent seen at the vitellogenin expression bioassay.

Animal models for the preneoplastic lesions of the prostate

OBJECTIVES

Reliable and adequate animal models are required, not only for investigation of etiology, pathogenesis, and treatment of prostate cancer, but also for chemoprevention of prostatic carcinogenesis.

METHODS

Animal models for the study of premalignant changes in the prostate are reviewed in the paper, with specific reference to the neonatally estrogenized mouse model.

RESULTS

Neonatal treatment of newborn Han:NMRI mice with synthetic non-steroidal estrogen, diethylstilbestrol (DES; 2 micrograms/pup on days 1-3 after birth) promoted hyperplastic and dysplastic changes in the periurethral region of the prostate at the age of 9-18 months. Dietary soy partially inhibited the development of prostatic dysplasia in these neonatally estrogenized animals, which may be due to phytoestrogens contained in soy-rich food.

CONCLUSION

Prostatic cancer and its possible precursors develop spontaneously, or can be induced by different chemical and hormonal manipulations in certain animal species and strains. Neonatal estrogenization of the mouse results in prostatic dysplasia, which can be partially prevented by dietary soy. There are morphological similarities between human prostatic intraepithelial neoplasia (PIN) and dysplastic changes in rodent prostates, but more data is needed before these dysplastic lesions can be considered equivalent to human PIN.

Phytoestrogens are partial estrogen agonists in the adult male mouse

The intake, as well as serum and urinary concentrations, of phytoestrogens is high in countries where incidence of prostate cancer is low, suggesting a chemopreventive role for phytoestrogens. Their significance could be explained by the ability to antagonize the action of more potent endogenous estrogens in initiation or promotion of tumor formation. We have studied estrogenicity and antiestrogenicity of dietary soy and two phytoestrogens, coumestrol and daidzein, in our neoDES mouse model for the study or prostatic neoplasia. Soy was chosen because it is rich in phytoestrogens, is widely used in Oriental diets, and has antiestrogenic and anticarcinogenic properties in the neoDES mouse when given from fertilization onward. In short-term tests with adult animals, no evidence for estrogenicity or antiestrogenicity (capability to antagonize the action of 17 beta-estradiol) of soy was found when development of epithelial metaplasia and expression of c-fos protooncogene in prostate were used as end points of estrogen action. Estrogenic activity of coumestrol and daidzein on c-fos expression was subtle. Coumestrol, either given alone or in combination with 17 beta-estradiol, had no effect on development of epithelial metaplasia. These marginal or missing effects in adult males could be interpreted by assuming that the neonatal period is more critical for estrogenic or antiestrogenic action of soy and phytoestrogens. Once initiated, estrogen-related lesions would develop spontaneously. Alternatively, the chemopreventive action of soy is not due to antiestrogenicity of soy-derived phytoestrogens.