Pragmatic diagnostic and therapeutic algorithms to optimize new potassium binder use in cardiorenal disease.

BACKGROUND: Pivotal randomized trials demonstrating efficacy, safety and good tolerance, of two new potassium binders (patiromer and sodium zirconium cyclosilicate) led to their recent approval. A major hurdle to the implementation of these potassium-binders is understanding how to integrate them safely and effectively into the long-term management of cardiovascular and kidney disease patients using renin angiotensin aldosterone system inhibitors (RAASi), the latter being prone to induce hyperkalaemia. METHODS: A multidisciplinary academic panel including nephrologists and cardiologists was convened to develop consensus therapeutic algorithm(s) aimed at optimizing the use of the two novel potassium binders (patiromer and sodium zirconium cyclosilicate) in stable adults who require treatment with RAASi and experience(d) hyperkalaemia in a non-emergent setting. RESULTS: Two dedicated pragmatic algorithms are proposed. The lowest intervention threshold (i.e. 5.1 mmol/L or greater) was the one used in the patiromer and sodium zirconium cyclosilicate) pivotal trials, both drugs being indicated to treat hyperkalaemia in a non -emergent setting. Acknowledging the heterogeneity across specialty guidelines in hyperkalaemia definition and thresholds to intervene when facing hyperkalaemia, we have been mindful to use soft language i.e. "it is to consider", not necessarily "to do". CONCLUSIONS: Providing the clinical community with pragmatic algorithms may help optimize the management of high-risk patients by avoiding the risks of both hyper and hypokalaemia and of suboptimal RAASi therapy.

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).

Diversity of leisure-time sport activities in adolescence as a predictor of leisure-time physical activity in adulthood.

Because sustained physical activity is important for a healthy life, this paper examined whether a greater diversity of sport activities during adolescence predicts higher levels of leisure-time physical activity (LTPA) in adulthood. From sport activity participation reported by 17-year-old twins, we formed five groups: 1, 2, 3, 4, and 5+ different sport activities. At follow-up in their mid-thirties, twins were divided into four activity classes based on LTPA, including active commuting. Multinomial regression analyses, adjusted for several confounders, were conducted separately for male (N=1288) and female (N=1770) participants. Further, conditional logistic regression analysis included 23 twin pairs discordant for both diversity of sport activities in adolescence and LTPA in adulthood. The diversity of leisure-time sport activities in adolescence had a significant positive association with adulthood LTPA among females. Membership in the most active adult quartile, compared to the least active quartile, was predicted by participation in 2, 3, 4, and 5+ sport activities in adolescence with odds ratios: 1.52 (P=.11), 1.86 (P=.02), 1.29 (P=.39), and 3.12 (P=5.4e-05), respectively. Within-pair analyses, limited by the small sample of twins discordant for both adolescent activities and adult outcomes, did not replicate the association. A greater diversity of leisure-time sport activities in adolescence predicts higher levels of LTPA in adulthood in females, but the causal nature of this association remains unresolved.

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 ß3 -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 ß3 -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.

Dynamin inhibition interferes with inflammasome activation and cytokine gene expression in Streptococcus pyogenes-infected human macrophages.

In the present study, we have analysed the ability of Streptococcus pyogenes [Group A streptococcus (GAS)] to activate the NACHT-domain-, leucine-rich repeat- and PYD-containing protein 3 (NALP3) inflammasome complex in human monocyte-derived macrophages and the molecules and signalling pathways involved in GAS-induced inflammatory responses. We focused upon analysing the impact of dynamin-dependent endocytosis and the role of major streptococcal virulence factors streptolysin O (SLO) and streptolysin S (SLS) in the immune responses induced by GAS. These virulence factors are involved in immune evasion by forming pores in host cell membranes, and aid the bacteria to escape from the endosome-lysosome pathway. We analysed cytokine gene expression in human primary macrophages after stimulation with live or inactivated wild-type GAS as well as with live SLO and SLS defective bacteria. Interleukin (IL)-1ß, IL-10, tumour necrosis factor (TNF)-α and chemokine (C-X-C motif) ligand (CXCL)-10 cytokines were produced after bacterial stimulation in a dose-dependent manner and no differences in cytokine levels were seen between live, inactivated or mutant bacteria. These data suggest that streptolysins or other secreted bacterial products are not required for the inflammatory responses induced by GAS. Our data indicate that inhibition of dynamin-dependent endocytosis in macrophages attenuates the induction of IL-1ß, TNF-α, interferon (IFN)-ß and CXCL-10 mRNAs. We also observed that pro-IL-1ß protein was expressed and efficiently cleaved into mature-IL-1ß via inflammasome activation after bacterial stimulation. Furthermore, we demonstrate that multiple signalling pathways are involved in GAS-stimulated inflammatory responses in human macrophages.

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.

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.

Glomerulonephritis emerging shortly after Puumala hantavirus infection: a report on 7 patients.

AIMS: Nephropathia epidemica (NE) is mild type of hemorrhagic fever caused by Puumala (PUU) hantavirus. Renal biopsy typically shows acute tubulointerstitial nephritis and complete recovery is the usual outcome. We previously described 5 patients with membranoproliferative glomerulonephritis (MPGN) after acute NE. We now report on 7 more patients who developed biopsy-confirmed glomerulonephritis (GN) during the convalescent phase of NE. MATERIAL AND METHODS: We present case histories of 7 patients with nephrotic-range proteinuria concomitant with hematuria after serologically verified NE. RESULTS: Renal biopsy specimens disclosed MPGN in 5 patients, membranous GN (MGN) in 1 and mesangial GN (MesGN) in 1. All patients achieved remission of nephrotic syndrome within a median time of 0.6 years (range 0.5 - 5.5 y). The median follow-up time was 1.7 years (0.7 - 15.6 y). CONCLUSIONS: As a rare phenomenon, nephrotic syndrome may emerge during the convalescent phase of acute PUU hantavirus infection. In most cases the prognosis of GN caused by NE seems to be favorable.

Steady state pharmacokinetics and dose equivalents of oral clodronate in renal failure.

OBJECTIVE: Clodronate is used in the treatment of osteoporosis, and malignancy-associated bone disease. The steady state pharmacokinetics and the dose equivalents of oral clodronate were assessed in subjects with various degrees of renal failure. MATERIALS AND METHODS: 1,600 mg of clodronate was given orally mornings for 11 days to 14 healthy volunteers (creatinine clearance, CLCr, > 80 ml/min), and 18, 12 and 16 subjects with mild (50 - 80 ml/min), moderate (30 - 50 ml/min) and severe (< 30 ml/min) renal failure, respectively. Trough drug levels at 4, 7 and 11 days, and concentration-time curves for 72 h after the last dose were followed. RESULTS: In all study groups, the trough drug levels achieved the kinetic steady state within 11 days. The area under the 24-h concentration-time curve (AUC0-24) enlarged and the elimination half-life (t1/2elim) prolonged progressively when the renal function was impaired. The maximum drug level and the time to maximum were not changed significantly in the renal failure. In the steady state phase, the diurnal drug excretion (E0-24) was not changed by the kidney function, but the renal drug clearance (CLD) decreased in close correlation with CLCr. The normal-to-failed AUC0-24 ratios in mild, moderate, and severe renal failure were 0.53, 0.43 and 0.31, respectively, when the ideally-matched counterpart was assumed as the normal reference to each renal failure group. CONCLUSIONS: In mild, moderate and severe renal failure, 53%, 43% and 31% oral clodronate doses, respectively, resulted in drug AUCs similar to those in controls with normal (> 80 ml/min) CLCR.

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

The role of early life genistein exposures in modifying breast cancer risk.

Review of the existing literature suggests that consumption of soy foods or an exposure to a soy isoflavone genistein during childhood and adolescence in women, and before puberty onset in animals, reduces later mammary cancer risk. In animal studies, an exposure that is limited to the fetal period or adult life does not appear to have the same protective effect. A meta-analysis of human studies indicates a modest reduction in pre- and postmenopausal risk when dietary intakes are assessed during adult life. These findings concur with emerging evidence indicating that timing may be vitally important in determining the effects of various dietary exposures on the susceptibility to develop breast cancer. In this review, we address the mechanisms that might mediate the effects of an early life exposure to genistein on the mammary gland. The focus is on changes in gene expression, such as those involving BRCA1 and PTEN. It will be debated whether mammary stem cells are the targets of genistein-induced alterations and also whether the alterations are epigenetic. We propose that the effects on mammary gland morphology and signalling pathways induced by pubertal exposure to genistein mimic those induced by the oestrogenic environment of early first pregnancy.

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.

Uterine expression of vascular endothelial growth factor is increased by estradiol and tamoxifen.

Vascular endothelial growth factor (VEGF) is an endothelial-specific mitogen with potent angiogenic activity. Because vascular growth accompanies normal endometrial regeneration and may also be involved in uterine tumor growth, we studied VEGF regulation by 17 beta-estradiol (E2) and tamoxifen, two agents that can increase uterine cell proliferation and tumor incidence. In immature, ovariectomized rats, E2 elevates uterine VEGF mRNA transiently, with a peak induction of 15-20-fold within 1 h. A maximum response is produced at a dose of 4 micrograms/kg E2, and induction is specific for estrogenic steroids. E2-dependent VEGF induction is inhibited by actinomycin D but not puromycin, suggesting that the effect is due at least in part to direct estrogen receptor regulation of VEGF transcription. PCR amplification and DNA sequencing indicated that VEGF188, VEGF164, and VEGF120 are all induced by E2, but the latter two are the predominant forms in the uterus. In situ hybridization shows a predominantly stromal expression of VEGF mRNA. The antiestrogens tamoxifen, 4-OH tamoxifen, and nafoxidine produce similar increases in uterine VEGF mRNA levels within 6 h, with 1 mg/kg tamoxifen producing a maximum response of 15-20-fold. The tamoxifen response was also inhibited by actinomycin D but not by puromycin, again suggesting direct transcriptional regulation of VEGF expression by antiestrogens. These findings raise the possibility that estrogen and antiestrogen effects on uterine edema, proliferation, and tumor incidence may involve local increases in tissue VEGF production.

Frequent loss of estrogen receptor-beta expression in prostate cancer.

The role of estrogen and its receptors in the etiology and progression of prostate cancer (PC) is poorly understood. In normal and malignant human prostate, estrogen receptor-alpha is expressed only in the stroma, whereas estrogen receptor-beta (ERbeta) is present in both normal stroma and epithelium. Because loss of ERbeta expression is associated with prostate hyperplasia in ERbeta-null mice, this study determined patterns of ERbeta expression in normal, hyperplastic, and malignant human prostate and associations with clinical outcome. Five normal prostates from organ donors and 159 radical prostatectomy specimens from patients with clinically localized PC were assessed for ERbeta expression using immunohistochemistry. ERbeta-positivity was defined as > or =5% of cells demonstrating nuclear immunoreactivity. All of the five normal prostates showed strong ERbeta-nuclear staining in >95% of the epithelium and 35% of the stromal cells. The number of ERbeta-positive cases declined to 24.2% (38/157) in hyperplasia adjacent to carcinoma and 11.3% (18/159) in PCs. ERbeta-positivity was related to decreased relapse-free survival (log-rank P = 0.04). Thus, loss of ERbeta expression is associated with progression from normal prostate epithelium to PC, whereas those cancers that retained ERbeta expression were associated with a higher rate of recurrence. These data identify the need to further investigate the potential role of ERbeta in the regulation of prostate epithelial cell proliferation and the functional consequences of decreased ERbeta expression in the evolution of PC.

Structural determinants of plant lignans for growth of mammary tumors and hormonal responses in vivo.

Low risk of breast cancer (BC) has been proposed to be associated with high intake of lignans. Some plant lignans are converted to mammalian lignans, e.g., enterolactone (ENL), suggested to be the biologically active lignan forms. Until now, little attention has been paid to the possible biological activities of plant lignans, even though some plant lignans are absorbed and present in serum and urine. In this study, we have investigated the antitumorigenic and endocrine-modulatory activities of different plant lignans in order to clarify the structure-activity relationships. 7-Hydroxymatairesinol (HMR) is [corrected] converted to ENL, and both HMR and ENL inhibit the growth of 7,12-dimethylbenz[a]-anthracene (DMBA)-induced mammary cancer. Nortrachelogenin (NTG) resembles HMR, but has a hydroxyl group at C-8 instead of C-7 and is not converted to ENL. In DMBA-model, NTG showed no inhibition of tumor growth, but increased the uterine weight. Furthermore, life-long exposure to NTG increased uterine weight in immature females and ventral prostate weight in adult males. In contrast, life-long exposure to HMR had no effects on uterine or prostate weights at any age. Our results indicate that a difference in the position of one hydroxyl group results in distinct biological responses in vivo, as well as different lignan metabolite profiles.

Weight gain and inflammation regulate aromatase expression in male adipose tissue, as evidenced by reporter gene activity.

Obesity and white adipose tissue (WAT) inflammation are associated with enhanced aromatization in women, but little is known about the regulation of aromatase (CYP19A1) gene expression in male WAT. We investigated the impact of weight gain and WAT inflammation on the regulation of CYP19A1 in males, by utilizing the hARO-Luc aromatase reporter mouse model containing a >100-kb 5'-region of the human CYP19A1 gene. We show that hARO-Luc reporter activity is enhanced in WAT of mice with increased adiposity and inflammation. Dexamethasone and TNFα, as well as forskolin and phorbol 12-myristate 13-acetate, upregulate hARO-Luc activity, suggesting the involvement of promoters I.4 and I.3/II. Furthermore, we show that diet enriched with antioxidative plant polyphenols attenuates WAT inflammation and hARO-Luc activity in obese males. In conclusion, our data suggest that obesity-associated WAT inflammation leads to increased peripheral CYP19A1 expression in males, and that polyphenol-enriched diet may have the potential to attenuate excessive aromatization in WAT of obese men.

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(DßH) 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(DßH) 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(DßH) 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(DßH) to the level of vehicle-treated wild-type mice. CONCLUSIONS: Altered endocannabinoid tone may underlie some of the metabolic dysfunctions in OE-NPY(DßH) 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(DßH) ) 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(DßH) 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.

Differential regulation of carbonic anhydrase II by androgen and estrogen in dorsal and lateral prostate of the rat.

Hormone regulation of carbonic anhydrase II (CA II) was studied in rat dorsal and lateral prostate. CA II is a major soluble protein in these accessory sex glands. The immunoelectronmicroscopy showed that CA II is expressed in their epithelial cells only. For studies on hormone regulation, adult male rats were castrated for 2 or 7 days. Groups of 7-day castrates and normal rats were treated daily either with testosterone or 17-beta-estradiol for 6 days and 2-day castrates for 1 day. CA II protein was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and quantified by RIA. The levels of CA II mRNA were studied by Northern blotting and hybridization of total RNA with a 32P-labeled mouse CA II cDNA clone. Castration of the rats decreased the concentration of CA II in lateral prostate but increased in dorsal prostate. These changes were reversed in both prostatic lobes by testosterone treatment. Estrogen treatment of castrated rats enhanced CA II concentration in lateral prostate but no effects were seen in the dorsal prostate of the same animals. In normal rats estrogen increased CA II concentration of dorsal prostate but there was no change in lateral prostate. Corresponding changes were observed in the levels of CA II mRNA in both tissues. The morphometric analyses showed that the castration- and hormone-induced changes of the mRNA and protein levels of the exclusively epithelial CA II could not be explained by any alterations in the proportions of epithelial and stromal components of the glands after hormone manipulations. The results demonstrate the differential steroid regulation of CAII in two prostatic lobes. Androgen regulates the expression of CAII at messenger RNA level, but the responses of CAII to testosterone are opposite in dorsal and lateral prostate. Estrogen increases CA II expression in lateral prostate but in dorsal prostate the castration-like effects of estrogen on CAII expression are probably indirect.