Regulation of PDE5 expression in normal prostate, benign prostatic hyperplasia, and adenocarcinoma.

BACKGROUND: Type 5 phosphodiesterase (PDE5) expression in the normal and pathological prostate is controversial. OBJECTIVES: This study aimed at identifying the cell type/s, if any, expressing PDE5 in human healthy or pathological prostate sections in order to further validate the rationale of PDE5 inhibitor (PDE5i) treatment of benign prostatic hyperplasia (BPH) and their safety in the treatment of erectile dysfunction following prostate cancer (PCa) surgery. MATERIALS AND METHODS: By immunohistochemical analysis, we studied PDE5 expression in tissue microarrays containing sections obtained from healthy, BPH, and PCa samples. RESULTS: Our results showed that PDE5 is barely expressed in the epithelial or stromal compartment of normal human prostates, but it is highly expressed in the stromal compartment of BPH sections. We also found that a low but significant number of PCa samples (22%) expressed PDE5 in the epithelial cancer cells but not in stromal cells and that such expression was not correlated with the tumor aggressiveness, according to their Gleason score. DISCUSSION AND CONCLUSION: PDE5 overexpression in the stromal compartment of BPH samples supports the rationale of PDE5 as a target in lower urinary tract symptoms of BPH. PDE5 expression in a significant percentage of PCa samples but the lack of correlation with the Gleason score suggests that this enzyme is not correlated with tumor aggressiveness; however, a role of PDE5 in the minimal residual disease of PCa cannot be excluded.

Multifractal analysis of diurnal temperature range over Southern Spain using validated datasets.

Multifractal properties of diurnal temperature range (DTR) have been analyzed in this work, using validated data of maximum and minimum temperature from 197 weather stations in Southern Spain (Andalusia region). DTR is a crucial factor to characterize the regional climate, providing more information than the average daily temperature. Apart from climate change studies, one of the most important applications of DTR in Agrometeorology is as an input variable in the solar radiation or reference evapotranspiration estimation models based on the temperature. With the aim of obtaining a detailed information for different time scales, different multifractal approaches have been applied. Different quality control methods such as range/limits or persistence tests were previously applied in order to detect incorrect and anomalous values, being discarded in the subsequent analysis. The DTR scaling of moments has been analyzed and the moment scaling exponent function K(q) has been obtained, finding some differences between weather stations. In addition, multifractal dimension (D1) and multifractal degree (MD) were also estimated, revealing differences at coastal and inland locations that show heterogeneity across the region, including its multifractal nature and its invariance for a range of scales. The nonlinear characterization carried out in this work improves the understanding of DTR as an indicator of climate changes, and it can have a very positive impact on the calibration of regional models for estimating solar radiation or reference evapotranspiration based on the temperature. This multifractal characterization can be used to group stations with similar nonlinear dynamics, regardless of their geographical features, in such a way that more accurate coefficients than conventional ones are used.

Transcriptional modulation of mitochondria biogenesis pathway at and above critical speed in mice.

High- or moderate-intensity endurance training leads to mitochondrial biogenesis via the peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α)/mitochondrial transcription factor A (Tfam) signaling pathway. Although this pathway is stimulated during acute exercise, the relationship between its activity and the intensity of the exercise has not been characterized. In animal studies, individualized running speeds have not previously been assessed. Here, we sought to determine whether this pathway was modulated after a bout of exhaustive exercise at different relative intensities (at and over critical speed (CS)). Our starting hypotheses were that (i) exercise-induced overexpression of PGC-1α in skeletal muscle falls at intensities above CS, and (ii) transcriptional activity of the mitochondrial biogenesis signaling cascade is intensity-sensitive at and above CS. To test these hypothesis, male Friend Virus B-Type mice were divided into a control group and three exercise groups (exercising at CS, peak velocity (vPeak) and 150 % CS, respectively). mRNA expression levels for genes involved in mitochondrial biogenesis signaling were analyzed in the quadriceps muscle. PGC-1α was overexpressed at all exercise intensities. We also identified that, PGC-1α mRNA expression was negatively correlated with exercise intensity and blood lactate levels but not with maximal oxygen uptake, vPeak, or CS. Expression of the PGC-1α co-activator peroxisome proliferator-activated receptor ß was negatively correlated with the exercise intensity. In contrast, expression levels of Tfam were dissociated from exercise intensity. Our data indicate that at the intensities used in endurance training, the expression of mitochondrial biogenesis genes is finely modulated by the relative intensity of exhaustive exercise.

Use of EPR and FTIR to detect biological effects of ultrasound and microbubbles on a fibroblast cell line.

Structural and functional effects of exposing murine fibroblasts (NIH 3T3) to therapeutic ultrasound at 1 MHz frequency are described. These bioeffects can be attributed to the formation of free radical species by sonolysis of water. When cavitation occurs, dissociation of water vapor into H atoms and OH radicals is observed; these H atoms and OH radicals combine to form H(2), H(2)O(2), and HO(2). The radicals can chemically modify biomolecules, for example enzymes, DNA, and lipids. Generation of free radicals during exposure to ultrasound with or without encapsulated microbubbles (contrast agents) was studied by use of electron paramagnetic resonance with DMPO spin trapping. Recently the potential for possible use of these microbubbles in gene therapy has been investigated, because of the ability of the stabilized microbubbles to release their content when exposed to ultrasound. Structural changes were studied by Fourier-transform infrared spectroscopy, and induction of possible genotoxic damage by exposure of the cells to therapeutic ultrasound at 1 MHz frequency with our experimental device was verified by use of the cytokinesis-block micronucleus assay.

PPARbeta activation induces rapid changes of both AMPK subunit expression and AMPK activation in mouse skeletal muscle.

AMP-activated protein kinases (AMPK) are heterotrimeric, αßγ, serine/threonine kinases. The γ3-AMPK subunit is particularly interesting in muscle physiology because 1) it is specifically expressed in skeletal muscle, 2) α2ß2γ3 is the AMPK heterotrimer activated during exercise in humans, and 3) it is down-regulated in humans after a training period. However, mechanisms underlying this decrease of γ3-AMPK expression remained unknown. We investigated whether the expression of AMPK subunits and particularly that of γ3-AMPK are regulated by the PPARß pathway. We report that PPARß activation with GW0742 induces a rapid (2 h) and sustained down-regulation of γ3-AMPK expression both in mouse skeletal muscles and in culture myotubes. Concomitantly, phosphorylation levels of both AMPK and acetyl-coenzyme A carboxylase are rapidly modified. The γ3-AMPK down-regulation is also observed in muscles from young and adult transgenic mice with muscle-specific overexpression of peroxisome proliferator-activated receptor ß (PPARß). We showed that γ3-AMPK down-regulation is a rapid physiological muscle response observed in mouse after running exercise or fasting, two situations leading to PPARß activation. Finally, using C2C12, we demonstrated that dose and time-dependent down-regulation of γ3-AMPK expression upon GW0742 treatment, is due to decrease γ3-AMPK promoter activity.

Cardiac allograft vasculopathy : complications and imaging studies.

Cardiac allograft vasculopathy (CAV) is an accelerated form of coronary artery disease affecting both intramyocardial and epicardial coronary arteries and is observed in patients during long-term survival after cardiac transplantation. We report a case of CAV complicated with silent transmural myocardial infarction and massive left ventricular thrombus formation associated with silent pericarditis and with ischemic and non-ischemic scar tissue, as detected by cardiac magnetic resonance imaging (CMRI). The authors suggest CMRI as an additional technique along with echocardiography during follow-up of heart transplant recipients. CMRI may contribute to the early identification of areas of myocardial wall abnormalities suggestive of CAV, thus guiding diagnosis and prompt percutaneous treatment.

UVB radiation induced effects on cells studied by FTIR spectroscopy.

We have made a preliminary analysis of the results about the effects on tumoral cell line (lymphoid T cell line Jurkat) induced by UVB radiation (dose of 310 mJ/cm(2)) with and without a vegetable mixture. In the present study, we have used two techniques: Fourier transform infrared spectroscopy (FTIR) and flow cytometry. FTIR spectroscopy has the potential to provide the identification of the vibrational modes of some of the major compounds (lipid, proteins and nucleic acids) without being invasive in the biomaterials. The second technique has allowed us to perform measurements of cytotoxicity and to assess the percentage of apoptosis. We already studied the induction of apoptotic process in the same cell line by UVB radiation; in particular, we looked for correspondences and correlations between FTIR spectroscopy and flow cytometry data finding three highly probable spectroscopic markers of apoptosis (Pozzi et al. in Radiat Res 168:698-705, 2007). In the present work, the results have shown significant changes in the absorbance and spectral pattern in the wavenumber protein and nucleic acids regions after the treatments.

Constitutive expression of suppressor of cytokine signalling-3 in skeletal muscle leads to reduced mobility and overweight in mice.

AIMS/HYPOTHESIS: Due to their ability to regulate various signalling pathways (cytokines, hormones, growth factors), the suppressor of cytokine signalling (SOCS) proteins are thought to be promising therapeutic targets for metabolic and inflammatory disorders. Hence, their role in vivo has to be precisely determined. METHODS: We generated transgenic mice constitutively producing SOCS-3 in skeletal muscle to define whether the sole abundance of SOCS-3 is sufficient to induce metabolic disorders and whether SOCS-3 is implicated in physiological roles distinct from metabolism. RESULTS: We demonstrate here that chronic expression of SOCS-3 in skeletal muscle leads to overweight in mice and worsening of high-fat diet-induced systemic insulin resistance. Counter-intuitively, insulin sensitivity in muscle of transgenic mice appears to be unaltered. However, following constitutive SOCS-3 production, several genes had deregulated expression, among them other members of the SOCS family. This could maintain the insulin signal into skeletal muscle. Interestingly, we found that SOCS-3 interacts with calcineurin, which has been implicated in muscle contractility. In Socs-3 transgenic muscle, this leads to delocalisation of calcineurin to the fibre periphery. Relevant to this finding, Socs-3 transgenic animals had dilatation of the sarcoplasmic reticulum associated with swollen mitochondria and decreased voluntary activity. CONCLUSIONS/INTERPRETATION: Our results show that constitutive SOCS-3 production in skeletal muscle is not in itself sufficient to induce the establishment of metabolic disorders such as diabetes. In contrast, we reveal a novel role of SOCS-3, which appears to be important for muscle integrity and locomotor activity.

Peroxisome proliferator-activated receptor beta activation promotes myonuclear accretion in skeletal muscle of adult and aged mice.

We reported recently that peroxisome proliferator-activated receptor beta (PPARbeta) activation promotes a calcineurin-dependent exercise-like remodelling characterised by increased numbers of oxidative fibres and capillaries. As physical exercise also induces myonuclear accretion, we investigated whether PPARbeta activation alters myonuclear density. Transgenic muscle-specific PPARbeta over-expression induced 14% increase of myonuclear density. Pharmacological PPARbeta activation promoted rapid and massive myonuclear accretion (20% increase after 48 h), which is dependent upon calcineurin/nuclear factor of activated T cells signalling pathway. In vivo bromodeoxyuridine labelling and proliferating cell nuclear antigen immunodetection revealed that PPARbeta activation did not promote cell proliferation, suggesting that the PPARbeta-promoted myonuclear accretion involves fusion of pre-existing muscle precursor cells to myofibres rather than cell division. Finally, we showed that in skeletal muscle, ageing led to a down-regulation of PPARbeta accompanied by decrease of both oxidative fibre number and myonuclear density. PPARbeta pharmacological activation counteracts, at least in part, the ageing-driven muscle remodelling.

Structural changes induced in proteins by therapeutic ultrasounds.

The structural effect induced by therapeutic ultrasound on proteins in aqueous solution has been investigated with FTIR spectroscopy, UV-VIS spectroscopy, circular dichroism and light scattering. Six proteins (cytochrome, lysozyme, myoglobin, bovine serum albumin, trypsinogen, and alpha-chymotrypsinogen A) with different molecular weight and secondary structure have been studied. The experiment has been performed using an ultrasound source at resonant frequency of 1 MHz and sonication times of 10, 20, 30, 40, 50, and 60 min. A different behaviour of proteins under sonication depends on the dominant secondary structure type (alpha-helix or beta-sheets) and on the grade of the ordered structure. The results suggest that the free radicals, produced by water sonolysis, have an important role in the changes of structural order.

Peroxisome proliferator-activated receptors as sensors of fatty acids and derivatives.

Lipid homeostasis requires a strict balance between lipid intake and consumption. This balance is controlled by different systems that regulate food intake, energy storage and energy expenditure. This review focuses on the roles of peroxisome proliferator- activated receptors (PPARs) in some of these regulatory processes. PPARs are transcription factors that bind and are activated by fatty acids and fatty acid derivatives. They act as lipid sensors and adapt the metabolism and development of various tissues to lipid availability. Due to their actions on lipid metabolism, PPARs are bona fide therapeutic targets in the treatment of metabolic syndrome not only by affecting gene expression patterns in several tissues but also by inducing remodeling of tissues such as adipose or skeletal muscle.

An uncommon large deletion in the androgen-receptor gene in a XY female with complete androgen insensitivity syndrome.

Androgen insensitivity is a disorder characterized by an abnormal male sexual development, in which the androgen action is impaired due to structural defects in the androgen receptor gene. We report a case of a 46,XY subject with female phenotype (normal breast and external genitalia) lacking sexual hair, affected with primary amenorrhea. In this patient, we found a deletion of a large region of the androgen receptor gene encoding the steroid-binding domain of the protein, causing a complete inability to bind the androgens. This uncommon molecular defect impaired the expression of androgen-dependent genes inducing the female phenotype.

Submento-submandibular intubation: is the subperiosteal passage essential? Experience in 107 consecutive cases.

Adequate treatment of panfacial injuries often requires tracheostomy or alternating intubation through the nose and the mouth to keep the field free during the operation. Altemir's submental technique is an attractive option in these patients. We used the method with a slight modification in 107 operations in our unit to treat panfacial injuries. We had a low rate of complications and no increased operative time.

PPAR delta: an uncompletely known nuclear receptor.

Peroxisome proliferator-activated receptors (PPAR) mediate some of the transcriptional effects of fatty acids and control many physiological functions, especially in the field of development and metabolism. Three isotypes are known, alpha, gamma, and B/delta. Roles of PPAR alpha and PPARgamma are now quite well-known, particularly since their pharmacologic ligands have been marketed, respectively the lipid-normalizing class of fibrates and the antidiabetic class of thiazolidinediones (glitazones). However, functions of PPARdelta are uncompletely known to date, but some recent data enlight its role in the regulation of fatty acid oxidation in several tissues, such as skeletal muscle and adipose tissue. Overexpression of PPARdelta using a transgenic murine model promotes an increase of muscle oxidative capability. This is accompanied by a redistribution of fatty acid flux, redirected from adipose tissue towards skeletal muscle. Finally, adipose mass is reduced, due to a decreased adipocyte size. These data strongly suggest that PPARdelta play a major role in the metabolic adaptations to western diet characterized by an excessive amount of saturated fat. Considering the metabolic properties of the two other PPAR isotypes, alpha and gamma, it is likely that the three PPAR isotypes have complementary effects in the pathophysiology of obesity and metabolic syndrome. Future therapeutical perspectives in this field should consider combined treatment, adding delta agonists (for all that their safety will be established) to the already available alpha and gamma agonists.

Roles of PPARdelta in the control of muscle development and metabolism.

PPARdelta (peroxisome proliferator-activated receptor delta)-specific agonists decrease plasma lipids and insulinaemia in obese animals. As skeletal muscle is one of the major organs for fatty acid catabolism, we have investigated the roles of the nuclear receptor in the control of muscle development and lipid metabolism, by using two approaches. We have used C(2)C(12) myotubes in which the PPARdelta activity was altered by overexpression of either native or dominant-negative (DN) mutant forms of PPARdelta. Treatment of C(2)C(12) cells by specific PPARdelta agonists promotes expression of genes for proteins of fatty acid catabolism and increases fatty acid oxidation. These responses were increased in C(2)C(12)-PPARdelta cells and impaired in C(2)C(12)-PPARdeltaDN cells. We also constructed animal models with muscle-specific expression of PPARdelta (Cre/Lox approach). The effects of muscle-specific alteration of PPARdelta activity were studied on muscle development and metabolism as well as on body fat mass. These experiments indicated that PPARdelta plays a crucial role in myofibre typing determination and regulation of muscle oxidative capabilities, and that muscle-specific overexpression of the nuclear receptor leads to reduction of adipocyte size and body fat mass. These data strongly suggest that PPARdelta controls fatty acid catabolism in muscle and that its activation by synthetic agonists could prevent or correct obesity and type 2 diabetes.

Molecular biology tools for dissecting sexual behavior.

The tools of molecular biology have just begun to demonstrate the role of genes in controlling sexual behavior and how hormones can influence sexual and reproductive motivation by controlling gene expression. In this review article the use of the new term "molecular sexology" is proposed to indicate the growing evidence that molecular biology techniques can be a useful tool not only to understand the genetic bases of the animal (and soon human) sexual behavior, but also in order to provide the rationale of the use of advanced therapeutic approaches, such as gene transfer, to the symptoms and diseases of sexuality.

Structural and functional characterization of the mouse fatty acid translocase promoter: activation during adipose differentiation.

Fatty acid translocase (FAT/CD36) is a cell-surface glycoprotein that functions as a receptor/transporter for long-chain fatty acids (LCFAs), and interacts with other protein and lipid ligands. FAT/CD36 is expressed by various cell types, including platelets, monocytes/macrophages and endothelial cells, and tissues with an active LCFA metabolism, such as adipose, small intestine and heart. FAT/CD36 expression is induced during adipose cell differentiation and is transcriptionally up-regulated by LCFAs and thiazolidinediones in pre-adipocytes via a peroxisome-proliferator-activated receptor (PPAR)-mediated process. We isolated and analysed the murine FAT/CD36 promoter employing C(2)C(12)N cells directed to differentiate to either adipose or muscle. Transient transfection studies revealed that the 309 bp upstream from the start of exon 1 confer adipose specific activity. Sequence analysis of this DNA fragment revealed the presence of two imperfect direct repeat-1 elements. Electrophoretic mobility-shift assay demonstrated that these elements were peroxisome-proliferator-responsive elements (PPREs). Mutagenesis and transfection experiments indicated that both PPREs co-operate to drive strong promoter activity in adipose cells. We conclude that murine FAT/CD36 expression in adipose tissue is dependent upon transcriptional activation via PPARs through binding to two PPREs located at -245 to -233 bp and -120 to -108 bp from the transcription start site.

Fatty acid regulation of gene expression.

Over the past 10 years it has become evident that fatty acids regulate cellular functions by modulating gene expression. Fatty acids and fatty acid metabolites exert some of their effects on gene expression by affecting the activity of nuclear transcription factors, peroxisome proliferator-activated receptors and sterol regulatory element binding protein type 1. The present review describes the latest developments in the field, with particular emphasis on the physiological roles of the various peroxisome proliferator-activated receptor isotypes, including their implication in the control of proliferation and differentiation of normal and malignant cells, and on the mechanisms implicated in the regulation of sterol regulatory element binding protein type 1 activity by polyunsaturated fatty acids.

The roles of PPARs in adipocyte differentiation.

Adipose tissue development takes place primarily around birth but adipose cell number can increase throughout life in response to nutritional changes. At the molecular level, adipogenesis is the result of transcriptional remodeling that leads to activation of a considerable number of genes. Several transcription factors act cooperatively and sequentially in this process. This article attempts to review the roles of peroxisome proliferator-activated receptors gamma and delta in the control of preadipocyte proliferation and differentiation during adipose tissue development or during the adaptive response of adipose tissue mass to high-fat feeding.