Norwegian general population normative data for the European Organization for Research and Treatment of Cancer questionnaires: the Quality of Life Questionnaire-Core 30, the Sexual Health Questionnaire QLQ-SHQ22 and the sexual domains of the QLQ-BR23/BR45

OBJECTIVE

The aim of this study was to provide sex-, age-, and morbidity-specific Norwegian general population normative values for the European Organization for Research and Treatment of Cancer Quality of Life Questionnaires QLQ-C30, the sexual health questionnaire QLQ-SHQ22 and the sexual domains of the breast modules QLQ-BR23 and QLQ-BR45.

METHODS

A random nationwide sample stratified by sex and age groups (18-29, 30-39, 40-49, 50-59, 60-69 and ≥70 years) was drawn from the Norwegian National Population Register. Participants were notified through national online health services (HelseNorge) and postal mail. The survey included sociodemographic background information, health-related quality of life assessed by the EORTC questionnaires, and morbidity assessed by the Self-Administered Comorbidity Questionnaire. Multivariable linear regression was carried out to estimate the associations of age, sex and morbidity with the EORTC scale and item scores.

RESULTS

Of the 15,627 eligible individuals, 5135 (33%) responded. Women and persons with morbidities reported lower functioning and higher symptom burden than men and persons without morbidities, respectively, on nearly all EORTC scales. Sex differences were most prominent for emotional functioning, pain, fatigue and insomnia (QLQ-C30), body image, sexual functioning (QLQ-BR23/45), importance of sexual activity, libido and fatigue (QLQ-SHQ22). The score differences between persons with and without morbidity were highly significant and largest in the youngest and middle-aged groups.

CONCLUSION

This is the first study to provide normative values for the EORTC sexual health questionnaire QLQ-SHQ22 and the sexual subscales of the QLQ-BR23 and QLQ-BR45 for all, separately in age groups by sex and morbidity.

Trait mindfulness and the mental and physical health of caregivers for individuals with cancer

BACKGROUND

Mindfulness plays a role in moderating the negative mental and physical health outcomes associated with caregiving. The aims of this study were to examine the relationship between trait mindfulness and the (1) psychological functioning, (2) health behaviors, (3) and physical health of caregivers for individuals diagnosed with cancer.

METHODS

Caregivers completed a battery of questionnaires and examinations assessing sociodemographic characteristics, trait mindfulness, depression, perceived stress, caregiver stress, sleep, diet, physical activity, tobacco use, alcohol use, blood pressure, and BMI. Demographics and cancer diagnostics were collected for the individuals whom caregivers supported. Linear regression, multivariate analyses, and moderator analyses were performed.

RESULTS

Of the 78 caregivers, the mean age was 63.9 (S.D.=13.1); 59% identified as female; 97% identified as White. Regression analyses indicated that caregivers who reported higher levels of trait mindfulness reported significantly less perceived stress (b= -4.38, SE= 0.88, p <.001), lower levels of depression (b= -3.74, SE= 1.10, p = .001), greater caregiver quality of life (b= -9.05, SE=2.12, p < .001), better sleep quality (b= -0.98, SE=0.44, p = 0.03), and lower rates of tobacco use (b= -10.12, SE= 3.43, p =.003). Trait mindfulness was not significantly related to diet, alcohol use, blood pressure, or BMI.

CONCLUSIONS

Higher levels of trait mindfulness are associated with positive mental and physical health measure for caregivers. Future research would benefit from further examining mindfulness-based interventions and their impacts in mitigating the negative toll of caregiving in the context of cancer.

Use of the ICRP system for the protection of marine ecosystems

The International Commission on Radiological Protection (ICRP) recently reinforced the international system of radiological protection, initially focused on humans, by identifying principles of environmental protection and proposing a framework for assessing impacts of ionising radiation on non-human species, based on a reference flora and fauna approach. For this purpose, ICRP developed dosimetric models for a set of Reference Animals and Plants, which are representative of flora and fauna in different environments (terrestrial, freshwater, marine), and produced criteria based on information on radiation effects, with the aim of evaluating the level of potential or actual radiological impacts, and as an input for decision making. The approach developed by ICRP for flora and fauna is consistent with the approach used to protect humans. The International Atomic Energy Agency (IAEA) includes considerations on the protection of the environment in its safety standards, and is currently developing guidelines to assess radiological impacts based on the aforementioned ICRP approach. This paper presents the method developed by IAEA, in a series of meetings with international experts, to enable assessment of the radiological impact to the marine environment in connection with the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 (London Convention 1972). This method is based on IAEA's safety standards and ICRP's recommendations, and was presented in 2013 for consideration by representatives of the contracting parties of the London Convention 1972; it was approved for inclusion in its procedures, and is in the process of being incorporated into guidelines.

Advances in NORM management in Norway and the application of ICRP's 2007 recommendations

In Norway, the largest reported quantities of radioactive discharges and radioactive waste containing naturally occurring radioactive material (NORM) come from the oil and gas sector, and smaller quantities of other NORM waste are also produced by industrial or mining processes. The Gulen final repository for radioactive waste from the oil and gas industry from the Norwegian continental shelf was opened in 2008 and has a capacity of 6000 tonnes. As of 1 January 2011, a new regulation was enforced whereby radioactive waste and radioactive pollution was integrated in the Pollution Control Act from 1981. This means that radioactive waste and radioactive pollution are now regulated under the same legal framework as all other pollutants and hazardous wastes. The regulation establishes two sets of criteria defining radioactive waste: a lower value for when waste is considered to be radioactive waste, and a higher value, in most cases, for when this waste must be disposed of in a final waste repository. For example, waste containing ≥ 1 Bq/g of Ra-226 is defined as radioactive waste, while radioactive waste containing ≥ 10 Bq/g of Ra-226 must be disposed of in a final repository. Radioactive waste between 1 and 10B q/g can be handled and disposed of by waste companies who have a licence for handling hazardous waste according to the Pollution Control Act. Alternatively, they will need a separate licence for handling radioactive waste from the Norwegian Radiation Protection Authority. The goal of the new regulation is that all radioactive waste should be handled and stored in a safe manner, and discharges should be controlled through a licensing regime in order to avoid/not pose unnecessary risk to humans or the environment. This paper will elaborate on the new regulation of radioactive waste and the principles of NORM management in Norway in view of the International Commission on Radiological Protection's 2007 Recommendations.

Mice lacking the Raf-1 kinase inhibitor protein exhibit exaggerated hypoxia-induced pulmonary hypertension

BACKGROUND AND PURPOSE

Increased pulmonary vascular remodelling, pulmonary arterial pressure and pulmonary vascular resistance characterize the development of pulmonary arterial hypertension (PAH). Activation of the Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK)1/2 is thought to play an important role in PAH and Raf-1 kinase inhibitor protein (RKIP), negatively regulates this pathway. This study investigated whether genetic deletion of RKIP (and hence ERK1/2 up-regulation) resulted in a pulmonary hypertensive phenotype in mice and investigated a role for RKIP in mitogen-regulated proliferative responses in lung fibroblasts.

EXPERIMENTAL APPROACH

Pulmonary vascular haemodynamics and remodelling were assessed in mice genetically deficient in RKIP (RKIP-/-) after 2 weeks of either normoxia or hypoxia. Immunoblotting and immunohistochemistry were used to examine phosphorylation of Raf-1, RKIP and ERK1/2 in mouse pulmonary arteries. In vitro, RKIP inhibition of mitogen signalling was analysed in CCL39 hamster lung fibroblasts.

KEY RESULTS

RKIP-/- mice demonstrated elevated indices of PAH and ERK1/2 phosphorylation compared with wild-type (WT) mice. Hypoxic RKIP-/- mice exhibited exaggerated PAH indices. Hypoxia increased phosphorylation of Raf-1, RKIP and ERK1/2 in WT mouse pulmonary arteries and Raf-1 phosphorylation in RKIP-/- mouse pulmonary arteries. In CCL39 cells, inhibition of RKIP potentiated mitogen-induced proliferation and phosphorylation of RKIP, and Raf-1.

CONCLUSIONS AND IMPLICATIONS

The lack of RKIP protein resulted in a pulmonary hypertensive phenotype, exaggerated in hypoxia. Hypoxia induced phosphorylation of RKIP signalling elements in WT pulmonary arteries. RKIP inhibition potentiated mitogen-induced proliferation in lung fibroblasts. These results provide evidence for the involvement of RKIP in suppressing the development of hypoxia-induced PAH in mice.

Treatment with the Kv7 potassium channel activator flupirtine is beneficial in two independent mouse models of pulmonary hypertension

BACKGROUND AND PURPOSE

Voltage-gated potassium (K(v)) channels contribute to resting membrane potential in pulmonary artery smooth muscle cells and are down regulated in patients with pulmonary arterial hypertension (PAH) and a contribution from K(v)7 channels has been recently proposed. We investigated the effect of the K(v)7 channel activator, flupirtine, on PAH in two independent mouse models: PAH induced by hypoxia and spontaneous PAH in mice over-expressing the 5-HT transporter (SERT(+) mice).

EXPERIMENTAL APPROACH

Right ventricular pressure was assessed in vivo in mice chronically treated with flupirtine (30 mg.kg(-1).day(-1)). In separate in vitro experiments, pulmonary arteries from untreated mice were mounted in a wire myograph. Relaxations to acute administration of flupirtine and contractions to K(v) channel blocking drugs, including the K(v)7 channel blocker linopirdine, were measured.

KEY RESULTS

In wild-type (WT) mice, hypoxia increased right ventricular pressure, pulmonary vascular remodelling and right ventricular hypertrophy. These effects were attenuated by flupirtine, which also attenuated these indices of PAH in SERT(+) mice. In the in vitro experiments, flupirtine induced a potent relaxant response in arteries from untreated WT and SERT(+) mice. The relaxation was fully reversed by linopirdine, which potently contracted mouse pulmonary arteries while other K(v) channel blockers did not.

CONCLUSIONS AND IMPLICATIONS

Flupirtine significantly attenuated development of chronic hypoxia-induced PAH in mice and reversed established PAH in SERT(+) mice, apparently via K(v)7 channel activation. These results provide the first direct evidence that drugs activating K(v)7 channels may be of benefit in the treatment of PAH with different aetiologies.

Prognostic impact of angiogenic markers in tumor and stromal cells in non-small cell lung cancer (NSCLC)

10596

Background: The vascular endothelial growth factors (VEGFs) -A, -C, -D and the vascular endothelial growth factor Receptors (VEGFRs) -1, -2 and -3 are important molecular markers in angiogenesis and lymphangiogenesis. This study elucidates the prognostic significance of these molecular markers in tumor cells as well as in the tumor stroma of resected NSCLC tumors. Methods: Tumor tissue samples from 335 resected patients with stage I to IIIA were obtained and tissue microarrays were constructed from duplicate cores of tumor cells and surrounding stromal tissue from each resected specimen. Immunohistochemistry was used to evaluate the expression of each molecular marker. Results: In univariate analyses, high tumor cell expression of VEGF-A (P = .0005), VEGFR-1 (P = .013), VEGFR-2 (P = .006) and VEGFR-3 (P = .0003), were negative prognostic indicators for disease-specific survival (DSS). The most significant correlations between angiogenic marker expression and DSS were observed in patients with T2 stage and/or with sqamous cell carcinomas. In tumor stroma, however, high expression of VEGF-A (P = .017), VEGF-C (P = .003), VEGF-D (P = .009), VEGFR-1 (P = .01) and VEGFR-2 (P = .019), correlated with good prognosis. In multivariate analyses, high expression in tumor cells of VEGFR-3 (P = .007) was an independent negative prognostic factor for DSS, whereas high VEGF-C (P = .004) expression in stromal cells had an independent positive impact on survival. Conclusions: While high tumor cell expression of VEGFR-3 is an independent predictor of reduced survival in primary NSCLC, high VEGF-C expression in stromal cells is, in contrast, a favorable independent prognostic indicator.

No significant financial relationships to disclose.

4-Hydroxynonenal immunoreactivity is increased in human hippocampus after global ischemia

Oxidative stress and lipid peroxidation may contribute to the pathology of neurodegenerative disorders such as Alzheimer's disease (AD) and cerebral ischemia. 4-Hydroxynonenal (4-HNE) is a toxic by-product of lipid peroxidation, and immunoreactivity to 4-HNE has been used to examine lipid peroxidation in the pathogenesis of AD and ischemia. This study sought to determine 1) if there are cellular alterations in 4-HNE immunoreactivity in the human hippocampus after global ischemia, and 2) whether possession of an apolipoprotein E (APOE) epsilon4 allele influenced the extent of 4-HNE immunoreactivity. 4-HNE immunoreactivity was assessed semi-quantitatively in the temporal lobe of a group of controls (n = 44) and in a group of patients who had an episode of global ischemia as a result of a cardiorespiratory arrest and subsequently died (n = 56, survival ranged from 1hr to 42 days). There was minimal cellular 4-HNE immunoreactivity in the control group. However, compared to controls, 4-HNE immunoreactivity was significantly increased in neurons (p < 0.0002) and glia (p < 0.0001) in the hippocampal formation after global ischemia. Possession of an APOE epsilon4 allele did not influence the extent of neuronal or glial 4-HNE immunostaining in the control or global ischemia group. There was a significant negative correlation between the extent of neuronal 4-HNE immunoreactivity with survival period after global ischemia (r2 = 0.0801; p < 0.036) and a significant positive correlation between the extent of glial 4-HNE immunoreactivity and survival after global ischemia (r2 = 0.2958; p < 0.0001). The data indicate a marked increase in neuronal and glial 4-HNE. This substantiates a role for lipid peroxidation in the pathogenesis of cerebral ischemia. There was no indication that APOE genotype influenced the extent of 4-HNE immunoreactivity.

Differential effects of 17beta-estradiol upon stroke damage in stroke prone and normotensive rats

We previously reported that during pro-estrus (high endogenous estrogen levels), brain damage after middle cerebral artery occlusion (MCAO) was reduced in stroke-prone spontaneously hypertensive rats (SHRSP) but not in normotensive Wistar Kyoto rat (WKY). In the present study, we examined the effect of exogenous estrogen on brain damage after MCAO in SHRSP and WKY. A 17beta-estradiol (0.025 mg or 0.25 mg, 21 day release) or matching placebo pellet was implanted into ovariectomized WKY and SHRSP (3 to 4 months old) who then underwent distal diathermy-induced MCAO 2 weeks later. Plasma 17beta-estradiol levels for placebo and 17beta-estradiol groups were as follows: WKY 0.025 mg 16.4 +/- 8.5 (pg/mL, mean +/- SD) and 25.85 +/- 12.6; WKY 0.25 mg 18.2 +/- 9.0 and 69.8 +/- 27.4; SHRSP 0.25 mg 20.7 +/- 8.8 and 81.0 +/- 16.9. In SHRSP, infarct volumes at 24 hours after MCAO were similar in placebo and 17beta-estradiol groups: SHRSP 0.025 mg 126.7 +/- 15.3 mm (n = 6) and 114.0 +/- 14.1 mm (n = 8) (not significant); SHRSP 0.25 mg 113.5 +/- 22.3 mm (n = 8) and 129.7 +/- 26.2 mm (n = 7) (not significant), respectively. In WKY, 17beta-estradiol significantly increased infarct volume by 65% with 0.025 mg dose [36.1 +/- 20.7 mm (n = 8) and 59.7 +/- 19.3 mm (n = 8) (P = 0.033, unpaired t-test)] and by 96% with 0.25 mg dose [55.9 +/- 36.4 mm (n = 8) and 109.7 +/- 6.7 mm (n = 4) (P = 0.017)]. Thus, 17beta-estradiol increased stroke damage in normotensive rats with no significant effect in stroke-prone rats. Despite being contrary to our hypothesis, our findings add substance to the recently reported negative effects of 17beta-estradiol in clinical studies.

Increased neuronal damage and apoE immunoreactivity in human apolipoprotein E, E4 isoform-specific, transgenic mice after global cerebral ischaemia

Apolipoprotein E (apoE, protein; APOE, gene) is expressed as three isoforms in humans (E2, E3, E4). The APOE-epsilon4 allele is associated with a poor outcome in patients after head injury of which ischaemic brain damage is a contributor of mortality and morbidity. The aim of the study was to determine whether mice expressing human APOE-epsilon4 displayed more extensive ischaemic neuronal damage 72 h after transient global ischaemia compared with mice which express human APOE-epsilon3. APOE-epsilon3 and -epsilon4 transgenic mice, under the control of a human promoter, were used which express human APOE in neurons and glia. Ischaemic neuronal damage in the CA1 pyramidal cell layer in the APOE-epsilon4 transgenic mice was significantly greater than in the APOE-epsilon3 mice after global ischaemia (36.4+/-8.9%, 18.2+/-7.3%; P<0.05). This was associated with more extensive neuronal apoE immunoreactivity in the CA1 pyramidal cell layer in the APOE-epsilon4 transgenic mice compared with APOE-epsilon3 transgenic mice. In contrast, in the caudate nucleus, there were similar levels of ischaemic neuronal damage in the APOE-epsilon3 and -epsilon4 transgenic mice (39.2 +/-10.1%; 44.6+/-8.4%, P = 0.32). In the caudate, similar numbers of neurons were immunostained for apoE in the APOE-epsilon3 and -epsilon4 transgenic mice. The present study demonstrated that the APOE-epsilon4 allele is associated with an increased vulnerability of a specific brain region to the effects of global ischaemia, which is closely associated with an increase in neuronal apoE. The data extend previous work and are consistent with an association of the APOE-epsilon4 allele with a poor outcome after acute brain injury in humans.

Intraventricular infusion of apolipoprotein E ameliorates acute neuronal damage after global cerebral ischemia in mice

The ability of intraventricular infusion of apolipoprotein E (apoE) to reduce neuronal damage after global cerebral ischemia was investigated in apoE-deficient and wild-type mice. ApoE (5 microg/mL lipid-conjugated derived from human plasma; 1 microL/h, continuous infusion) significantly reduced neuronal damage in the caudate nucleus and CA2 pyramidal cell layer by approximately 50% in apoE-deficient mice after global ischemia compared to vehicle infusion. In wild-type mice infused with apoE, there was a trend for ischemic neuronal damage to be reduced. ApoE-infused mice had a marked reduction in 4-hydroxynonenal immunoreactivity, as a marker of lipid peroxidation. The results show that the presence of apoE at or after the time of injury can be neuroprotective, possibly via an anti-oxidant mechanism.

DNA polymorphisms of the apolipoprotein B gene (XbaI, EcoRI, and MspI RFLPs) in Norwegians at risk of atherosclerosis and healthy controls

OBJECTIVES

Apo B is the exclusive protein constituent of LDL and is ligand on LDL, recognized and bound by the LDL receptor. Several restriction fragment length polymorphisms (RFLPs) of the apo B gene have been shown to be associated with variation in serum lipid levels in different populations. In this study we sought to determine the frequency of XbaI, EcoRI, and MspI polymorphisms and the haplotypes generated by these three polymorphic sites of the apo B gene and their influence on lipid levels in a sample of Norwegian subjects at risk of atherosclerosis and healthy control subjects.

METHODS AND RESULTS

108 White Norwegians at risk of atherosclerosis (cases) and 64 healthy individuals (controls) were examined for possible association between the alleles at the XbaI (X), EcoRI (R), and MspI (M) polymorphic restriction sites of the apolipoprotein B gene and serum lipid levels. The frequency of the M allele (absence of restriction site) was significantly higher in cases with high total cholesterol (TC), high low-density lipoprotein cholesterol (LDLC), and high apolipoprotein B (apo B) than in controls with normal TC, LDLC, and apo B (P < 0.04, P < 0.02, and P < 0.01, respectively). The frequencies of apo B genotypes detected with XbaI, EcoRI, and MspI did not differ significantly between cases and control subjects. A significant association between MspI genotypes and TC (P < 0.02), LDLC (P = 0.03), and apo B (P = 0.001) was observed only in cases. However, cases with the genotype M+/M+ had the lowest and those with the genotype M+/M- had the highest levels of serum TC, LDLC, and apo B. We did not observe any significant association between the alleles or genotypes detected with XbaI or EcoRI and serum lipid levels. In cases, genotypes defined by EcoRI and MspI RFLP paired loci differed significantly for apo B (chi 2 = 19; P = 0.007) but not for other blood lipids. EcoRI and MspI RFLPs change glutamic acid (Glu) 4154 to lysine (Lys) and arginine (Arg) 3611 to glutamine (Gln), respectively, which lie near the low density lipoprotein receptor binding region of apo B. Haplotypes containing "Lys/Arg Lys/Arg" (all basic amino acids) in cases were associated with low serum TC, LDLC, and apo B. In individuals at risk of atherosclerosis the concentration of serum lipids tends to be inversely related to the number of lysine and arginine.

CONCLUSION

We conclude that variations in the apo B gene, resulting in changes of charged amino acids, affect the circulating blood lipids and that these may contribute to the risk of atherosclerosis.

Specificity studies of an antibody developed against a mucin-type glycoprotein

The specificity of a new anti-epiglycanin antibody (AE-3) which recognizes a mucin-type glycoprotein, the Human Carcinoma Antigen, found in the blood of patients with carcinomas, was studied. Information regarding the chemical nature of the antibody binding site was obtained by altering the structure of epiglycanin by chemical or enzymic means and testing the product in a competitive binding assay for inhibition of the binding of AE-3 to epiglycanin. The need for a high molecular weight antigen containing clustered T disaccharide, Gal,1-3GalNAc, was demonstrated. The specificity was further explored by inhibition studies with glycopeptides having one to three mono- to disaccharides. The results were interpreted using computer graphics molecular modeling which predicted the specific recognition of hydroxyl groups on oligosaccharides on adjacent amino acids. Thus T antigen O-linked glycopeptide tumour markers can be designed to be distinguished by antibodies by the amount of clustering of their oligosaccharides.

Marked alterations in the cellular localisation and levels of apolipoprotein E following acute subdural haematoma in rat

Apolipoprotein E (apoE) plays a role in the response to acute brain injury, the mechanisms as yet remain unknown. In the present study, alterations in the immunohistochemical localisation of apoE in rat cortex were examined at 30 min, 2 h or 4 h following production of an acute subdural haematoma. Levels of apoE were determined in cortex by immunoblotting at 30 min and 4 h post-haematoma. Extensive areas of ischaemic cell damage were observed in the cortex underlying the haematoma with minimal damage observed in shams. In sham animals, apoE immunoreactivity was confined to astrocytes and their processes. Following the haematoma induction, apoE immunoreactivity was dramatically altered. At 30 min post-haematoma, intense apoE staining was observed in clusters of neuronal perikarya and the neuropil throughout the cortical layers underlying the haematoma and this persisted at 2 h and 4 h post-haematoma. Additionally, at 4 h post-haematoma marked apoE staining of discrete foci within the neuropil closely associated with capillaries was consistently observed in the ipsilateral cortex. Immunoblotting indicated there were no significant alterations in the cortical levels of apoE at 30 min post-haematoma but, at 4 h post-haematoma, there was a significant elevation (27%, P < 0.001) in the levels of apoE in cortex underlying the haematoma compared to control levels. The results indicate that following acute subdural haematoma, a rapid cellular redistribution of apoE occurs and precedes a significant elevation in the levels of apoE. These alterations in apoE may occur, at least initially, as part of the brain's protective response to injury.

Estrone sulfatase activity in guinea pig tissues

Estrone sulfatase activity is widespread in guinea pig tissues. Whole homogenates of adult testis, uterus, lung, adrenal, amnion, ovary, chorion, small intestine, placenta, spleen, kidney and liver exhibit approximately descending order of specific activity. Certain properties, including pH requirement, lack of inhibition by inorganic sulfate and magnitude of estimated Km values, are similar to that for arylsulfatase C of rat liver. Of the subcellular fractions prepared from guinea pig tissues, microsomes exhibit the highest specific activity although considerable enzyme activity remains associated with large cellular fragments sedimenting at 750 g. The sulfatase activity is readily inhibited by inorganic phosphate even when substrate concentration satisfied zero order kinetics. Rat liver arylsulfatase C is not inhibited under these conditions. Sensitivity of the guinea pig enzyme activity to inhibition by a variety of steroids and related compounds, is markedly less than for rat liver. Diethylstilbestrol(DES) strongly inhibits the rat liver enzyme but has little effect on the guinea pig liver system. Guinea pig testicular activity is suppressed to a degree intermediate between these extremes by increasing DES concentration. In guinea pig lung, kidney, and possibly liver, elevated fetal enzyme activities decrease from neonatal to adult life. Testicular activity appears to follow the opposite trend. Uterine enzyme activity is not markedly affected by pregnancy.

16-Hydroxylation of estrone-3-sulfate and estrone in the guinea pig in vivo

[6,7-3H]Estrone-3-sulfate or [6,7-3H]-estrone of high specific activity was injected into adult female English Shorthair guinea pigs. Blood, liver, kidney, gall bladder bile, and urine were obtained and investigated for metabolites. Chromatographic procedures followed by enzymatic or solvolytic cleavage of conjugates and subsequent crystallization with appropriate carrier steroids revealed the pattern of metabolites formed. Injected estrone sulfate was partially hydrolyzed and reconjugated, resulting in the production of estrone and estradiol glucuronides. The main metabolites, however, were monosulfates of 16alpha-hydroxyestrone, 16-keto-17beta-estradiol, and estriol as well as disulfates of 16alpha-hydroxyestrone, estriol, and 16beta-hydroxyestrone. Particularly high amounts of these were found in urine. By far the main metabolites of injected estrone were glucuronides of estrone and estradiol, although the pattern of mono- and disulfated steroids was qualitatively similar to that found after estrone sulfate injection. It is concluded that the guinea pigs employed in the study hydroxylated estrogen in the 16alpha- and 16beta-configurations and that this activity was much more pronounced after injection of estrone sulfate than after estrone.

Evidence for 16beta-hydroxylation of estrogens by guinea pig liver slices

In an earlier communication, we conclusively proved that estrone-3-sulfate could be hydroxylated in the 16alpha position by guinea pig liver slices. Disulfates of 16alpha-hydroxyestrone and estriol were identified. Suggestive evidence for 6-hydroxylated metabolites was also mentioned. A careful reinvestigation has now shown that the steroid disulfate fraction is composed of 16alpha- and 16beta-hydroxylated steroids. 16beta-Hydroxyestrone in particular is an important quantitative metabolite of estradiol-17 beta. It is concluded that no firm evidence is available for the formation of 6-hydroxysteroids in the tissue system under consideration.

In vitro and in vivo studies on the metabolism of estrogens and their sulfates in guinea pigs

Labelled estradiol-17 beta(E2) or estrone (E1), when incubated with guinea pig liver slices, is metabolized by two main pathways. Part of each substrate is converted to estrone-3-glucuronide and estradiol-3-glucuronide. A further part of each is metabolized to estradiol-3-sulfate (E23S) and estrone-3-sulfate (E13S), which are interconverted. The latter conjugate appears to be the substrate for a 16 alpha-hydroxylase forming 16 alpha-hydroxyestrone-3-sulfate (16 alpha OHE13S). This, in turn, is further sulfurylated to yield 16 alpha-hydroxyestrone-3, 16-disulfate, accompanied by estriol-3,16-disulfate. A relatively small amount of tentatively indentified '6-hydroxyestrone disulfate accompanies these other two diconjugates. The guinea pig liver system suggests itself as a useful and relatively simple model for further study of 16 alpha-hydroxylation of E13S. The use of the latter as a natural subd E23S are present in liver, kidney, blood, gallbladder bile, intestine, uterus, and placenta after injection of labelled E2 into mature male and female guinea pigs. Some evidence has been obtained for the disulfate fraction (above) in liver and bile after injection of labelled E1.

17-oxidoreduction of 17beta estradiol, estrone and their 3-sulfates by kidney slices from guinea pig and human

Slices of whole kidney and kidney cortex from the female guinea pig catalyzed a marked reduction of estrone 3-sulfate (E13S) and estrone (E1) to 17beta-estradiol 3-sulfate (E23S) and 17beta-estradiol (E2), respectively, as well as the reverse (dehydrogenation) reactions. Slices of medulla did not appear active in E23S-E13S interconversion but did possess the ability to interconvert E2 and E1, besides possessing considerable sulfatase activity. The use of [3H-55S]E13S and [3H-55S]E23S as substrates, together with a demonstrated lack of estrogen sulfate synthesis by the tissue slices, provided ample evidence that the intact sulfates were involved in direct oxidoreduction. Slices of human kidney cortex catalyzed the reduction of E13S to a very limited extent. Slices of whole kidney and of cortex from guinea pig formed small amounts of estrogen glucuronide(s).

Metabolism of estrogens and thier sulfates by mouse kidney tissue in vitro

Whole kidney tissue from mouse was incubated with labelled estrone 3-sulfate (E13S), 17beta-estradiol 3-sulfate (17betaE23S), estrone (E1), and 17beta-estradiol (17betaE2). Considerable reduction of E13S and E1 occurred. E13S gave rise primarily to 17alpha-estradiol 3-sulfate (17 alphaE23S) together with lesser amounts of 17betaE23S. By incubating [3H-35S]E13S with the tissue it was confirmed that formation of the diol sulfates was direct, without accompanying hydrolysis and reconjugation. Conversion of E1 was mainly to 17betaE2 with, on the average, lesser amounts of 17alphaE2. A small degree of direct conversion of 17betaE23S to E13S was found. 17beta-Estradiol was converted to a limited extent to E1 and to much smaller amounts of 17alphaE2.

Evidence for 16alpha-hydroxylation of estrone 3-sulphate by guinea pig liver slices

[6,7-3H,35S]Estrone 3-sulfate (E13S) of 3H/35S = 3.57 was incubated with female guinea pig liver slices. Small amounts of free steroid and estrone-3-glucuronide, each containing 3H, were found. In addition, E13S, 17beta-estradiol 3-sulfate, and a 'disulfate' fraction, with 3H/35S = 4.4, 4.3, and 4.7, respectively, were also isolated from the incubated tissue. The latter fraction was a major metabolite and about 45% of it consisted of 'disulfates' of 16alpha-hydroxyestrone and estriol, thus providing strong evidence for 16alpha-hydroxylation in guinea pig liver slices.

In vitro metabolism of 17beta-estradiol by human liver tissue

17beta-[6,7- 3H]Estradiol was incubated with adult human liver slices in Krebs-Ringer phosphate buffer containing glucose. Of the identified 3H recovered, 51-76 percent consisted of estrone-3-sulfate (E13S) and 17 beta-estradiol-3-sulfate (E23S). E13S was the main metabolite and was found in both tissue and medium. E23S was present only in the medium. Minor amounts of estrogen glucuronides were formed. When a human liver homogenate was incubated with [3H]E2 in a medium fortified with excess uridine diphosphate glucuronic acid only some 4 percent of conjugation with glucuronic acid was observed. It is suggested that human liver favors sulfurylation as the conjugating mechanism for E2 and E1.

Direct conversion of 17beta-estradiol-3-glucosiduronate and 17beta-estradiol-3-sulfate to their 17-keto forms by human kidney homogenates

Labelled 17β-estradiol-3-glucosiduronate and 17β-estradiol-3-sulfate were both directly dehydrogenated to their respective 17-keto forms on incubation with human kidney homogenates. NAD increased the conversion to a greater extent than did NADP. The reverse reaction, even in the presence of NADH or NADPH was not found to a measurable extent, presumably because of rapid oxidation of the cofactors. High or low activity towards the conjugates was accompanied by high or low activity, respectively, towards free 17β-estradiol. These dehydrogenase activities were particularly high in the medulla of one kidney so investigated. Considerable sulfatase activity was usually encountered in these homogenates but little β-glucuronidase activity was demonstrated under the experimental conditions.

Formation of estrogen glucosiduronates by human kidney homogenates

17β-Estradiol-6,7-3H (E2), 17β-estradiol-6,7-3H-3-sulfate (E23S), and estriol-6,7-3H (E3) were each incubated with human kidney homogenates in the presence of uridine diphosphoglucuronic acid. Metabolites were purified by DEAE-Sephadex and Celite partition chromatography and were identified by crystallization with carrier steroid conjugates and free steroids. E2 was converted to a small but definite extent (< 0.1–5%) to estrone-3-glucosiduronate, 17β-estradiol-3-glucosiduronate, and 17β-estradiol-17-glucosiduronate, the latter conjugate usually predominating. Under the experimental conditions E2 was a better precursor of all three conjugates than was E23S. In one experiment where kidney cortex and medulla were incubated separately with E2, the former was some 20 times more efficient in glucosiduronate synthesis. E3 was converted to the extent of 52–91% to estriol-16-glucosiduronate by whole kidney homogenates.

Metabolism of intravenously administered 17 -(6,7- 3 H)estradiol-17-glucoside in normal women

17α-[6,7-3H]estradiol-17-glucoside was injected intravenously into two normal young women. Within 72 h, 60 and 46% of the 3H dose was excreted in the urine in the two experiments. In the first 6 h, 4 and 1.4% of the dose was excreted as the unchanged glucoside, together with 14 and 5% in the form of a double conjugate, identified as 17α-estradiol-3-glucuronide-17-glucoside. Over the periods 6–24 h and 24–48 h none of the injected glucoside and only minor amounts of the double conjugate were present in the urine. The main excretory product after 6 h was 17 α-estradiol-17-glucuronide. This latter result contrasts with that obtained in previous experiments in which 17β-estradiol-6,7-3H-17-glucoside was injected, and in which the main monoconjugates excreted were the 3-glucuronides of 17β-estradiol and estrone.

Contribution of Estriol to Total Urinary Estrogens during Pregnancy

Estriol accounts for an average of 74% of the principal Kober-positive steroids in the urine of 13 women during uncomplicated pregnancies. This proportion is independent of the stage of pregnancy, from 20 weeks until term. The average ratio of estriol to ring-D α-ketols (mainly 16α-hydroxyestrone and 16-ketoestradiol-17β) is about 5:1 over the same period. In 17 pregnant women with diabetes, urinary estriol averaged 63% of the "total steroids" during a similar period, and the average ratio of estriol to ring-D α-ketols was 3:1. The quantitative importance of these ketolic steroids may introduce a problem in deciding whether to measure estriol or "total estrogens" when evaluating fetal viability in complicated pregnancies.

Peripheral interconversion of phenolic steroids in the human

A tracer dose of estradiol-17β-6,7-3H was injected intravenously into male subjects simultaneously with a14C-labeled steroid. The latter was either 16-ketoestradiol-17β-16-14C, 16-epiestriol-16-14C, or estriol-16-14C. All eight urinary metabolites of estradiol-17β-3H studied, and the main metabolites of the 16-oxygenated steroids, were predominantly split by β-glucuronidase hydrolysis. The major urinary metabolite released by solvolysis was estrone, as a conversion product of estradiol-17β-3H. After injection of estradiol-17β-3H together with either 16-ketoestradiol-17β-14C or 16-epiestriol-14C, urinary 16β-hydroxyestrone contained both isotopes. 16α-Hydroxyestrone, on the other hand, contained3H but only insignificant amounts of14C. This suggests formation of 16β-hydroxy-estrone but not 16α-hydroxyestrone from these injected 16-oxygenated steroids. 16-Epiestriol was metabolized to identifiable urinary metabolites to a considerably greater degree than was estriol. This was confirmed in a further experiment in which only 16-epiestriol-14C was injected.