Dietary conjugated linoleic acid downregulates the AlCl3-induced hyperactivation of compensatory and maladaptive signalling in the mouse brain cortex.

Oxidative stress, hyperactivation of compensatory mechanisms (unfolded protein response, UPR; nuclear factor erythroid 2-related factor 2, Nrf2) and the stimulation of maladaptive response (inflammation/apoptosis) are interconnected pathogenic processes occurring during Alzheimer's disease (AD) progression. The neuroprotective ability of dietary Conjugated linoleic acid (CLAmix) in a mouse model of AlCl3-induced AD was recently described but, the effects of AlCl3 or CLAmix intake on these pathogenic processes are still unknown. The effects of dietary AlCl3 or CLAmix - alone and in combination - were examined in the brain cortex of twenty-eight BalbC mice divided into 4 groups (n = 7 each). The neurotoxic effects of AlCl3 were investigated in animals treated for 5 weeks with 100 mg/kg/day (AL). CLAmix supplementation (600 mg/kg bw/day) for 7 weeks (CLA) was aimed at evaluating its modulatory effects on the Nrf2 pathway while its co-treatment with AlCl3 during the last 5 weeks of CLAmix intake (CLA + AL) was used to investigate its neuroprotective ability. Untreated mice were used as controls. In the CLA group, the NADPH oxidase (NOX) activation in the brain cortex was accompanied by the modulation of the Nrf2 pathway. By contrast, in the AL mice, the significant upregulation of oxidative stress markers, compensatory pathways (UPR/Nrf2), proinflammatory cytokines (IL-6, TNFα) and the proapoptotic protein Bax levels were found as compared with control. Notably, in CLA + AL mice, the marked decrease of oxidative stress, UPR/Nrf2 markers and proinflammatory cytokines levels were associated with the significant increase of the antiapoptotic protein Bcl2. The involvement of NOX in the adaptive response elicited by CLAmix along with its protective effects against the onset of several pathogenic processes triggered by AlCl3, broadens the knowledge of the mechanism underlying the pleiotropic activity of Nrf2 activators and sheds new light on their potential therapeutic use against neurodegenerative disorders.

Conjugated linoleic acid downregulates Alzheimer's hallmarks in aluminum mouse model through an Nrf2-mediated adaptive response and increases brain glucose transporter levels.

Mitochondrial dysfunction, oxidative stress, inflammation and glucose dysmetabolism are pathological signs of Alzheimer's disease (AD). Dietary aluminum (Al) overload is often used to induce AD in rodents and trigger the onset of oxidative-stress hallmarks resembling those of the human disease. The Nuclear factor erythroid 2-related factor 2 (Nrf2), owing to its key role in redox homeostasis, mitochondrial function and inflammation, is a promising drug target for neurological disorders, but only a few data are available on its modulatory effects on glucose transporter expression levels. While it has been found that the protective effect of Conjugated linoleic acid (CLA) occurs through the activation of an Nrf2-mediated adaptive response, its beneficial effect on the considered pathological signs in the Al-induced model has not been established yet. Thirty-five male BalbC mice were divided into 5 groups: two Al-intoxicated groups were treated for 5 weeks with low or high Al doses (8 or 100 mg/kg/day in drinking water, respectively; L or H). Two groups of animals, orally supplemented with CLA (600 mg/kg bw/day) for 7 weeks (2 preliminary weeks plus the 5-week treatment with Al; CLA + L, CLA + H) were used to investigate its protective effect, while untreated mice were used as control (Cntr). We provide evidence that mitochondrial dysfunction, Nrf2 alteration, inflammation and Acetylcholinesterase (AChE) hyperactivation can occur even from L exposure. Interestingly, animal pre-treatment with an allometric CLA dose led to significant downregulation of the toxic effects elicited by L or H, likely through the activation of an adaptive response. In conclusion, CLA ability to increase the level of glucose transporters - along with its antioxidant and anti-inflammatory effect - expands the therapeutic targets of these molecules and comes out as an intriguing suitable candidate for the treatment of multifactorial disease.

Curcumin dietary supplementation ameliorates disease phenotype in an animal model of Huntington's disease.

Huntington's disease (HD) has traditionally been described as a disorder purely of the brain; however, evidence indicates that peripheral abnormalities are also commonly seen. Among others, severe unintended body weight loss represents a prevalent and often debilitating feature of HD pathology, with no therapies available. It correlates with disease progression and significantly affects the quality of life of HD patients. Curcumin, a naturally occurring polyphenol with multiple therapeutic properties, has been validated to exert important beneficial effects under health conditions as well as in different pathological settings, including neurodegenerative and gastrointestinal (GI) disorders. Here, we investigated the potential therapeutic action that curcumin-supplemented diet may exert on central and peripheral dysfunctions in R6/2 mice, a well-characterized HD animal model which recapitulates some features of human pathology. Maintenance of normal motor function, protection from neuropathology and from GI dysfunction and preservation of GI emptying and conserved intestinal contractility, proved the beneficial role of life-long dietary curcumin in HD and corroborated the potential of the compound to be exploited to alleviate very debilitating symptoms associated with the disease.

Misconceptions of Spanish general practitioners' attitudes toward the management of urinary tract infections and asymptomatic bacteriuria: an internet-based questionnaire study.

OBJECTIVE: The diagnosis and management of urinary tract infections (UTI) vary widely across countries and practices. The objective of this study was to gain insight into general practitioners' (GP) perceptions on the current management of UTIs and asymptomatic bacteriuria in Spain. METHODS: Cross-sectional, internet-based questionnaire study answered from July to September 2013. GPs affiliated with the largest Spanish scientific society in primary care (Sociedad Española de Medicina Familiar y Comunitaria) were invited to participate in the study. They were asked about the tests ordered in both uncomplicated and complicated UTIs and about the management in three clinical scenarios, depicting a 50-year woman with: 1. An uncomplicated UTI, 2. A complicated UTI, and 3. An asymptomatic bacteriuria. RESULTS: The questionnaire was completed by 1,239 GPs (6.7%). Urine cultures were reportedly requested by 26.3% of the GPs in uncomplicated UTIs and by 71.8% of the cases corresponding to the complicated UTIs whereas it was declared that dipsticks were the preferred tests in only uncomplicated UTIs (38.2%). A total of 22% and 13.2% of the GPs stated that they would withhold antibiotic therapy in patients with low-count and high-count asymptomatic bacteriuria, respectively. CONCLUSIONS: GPs have important misconceptions as to the indications for ordering urine cultures and in interpreting the definitions of common UTIs and treating UTIs and asymptomatic bacteriuria. The unnecessary use of antibiotics in patients with asymptomatic bacteriuria is considerable in Spain.

Deregulation of MicroRNAs mediated control of carnitine cycle in prostate cancer: molecular basis and pathophysiological consequences.

Cancer cells reprogram their metabolism to maintain both viability and uncontrolled proliferation. Although an interplay between the genetic, epigenetic and metabolic rewiring in cancer is beginning to emerge, it remains unclear how this metabolic plasticity occurs. Here, we report that in prostate cancer cells (PCCs) microRNAs (miRNAs) greatly contribute to deregulation of mitochondrial fatty acid (FA) oxidation via carnitine system modulation. We provide evidence that the downregulation of hsa-miR-124-3p, hsa-miR-129-5p and hsa-miR-378 induced an increase in both expression and activity of CPT1A, CACT and CrAT in malignant prostate cells. Moreover, the analysis of human prostate cancer and prostate control specimens confirmed the aberrant expression of miR-124-3p, miR-129-5p and miR-378 in primary tumors. Forced expression of the miRNAs mentioned above affected tumorigenic properties, such as proliferation, migration and invasion, in PC3 and LNCaP cells regardless of their hormone sensitivity. CPT1A, CACT and CrAT overexpression allow PCCs to be more prone on FA utilization than normal prostate cells, also in the presence of high pyruvate concentration. Finally, the simultaneous increase of CPT1A, CACT and CrAT is fundamental for PCCs to sustain FA oxidation in the presence of heavy lipid load on prostate cancer mitochondria. Indeed, the downregulation of only one of these proteins reduces PCCs metabolic flexibility with the accumulation of FA-intermediate metabolites in the mitochondria. Together, our data implicate carnitine cycle as a primary regulator of adaptive metabolic reprogramming in PCCs and suggest new potential druggable pathways for prevention and treatment of prostate cancer.

Exosomal microRNAs in liquid biopsies: future biomarkers for prostate cancer

Prostate cancer is the second most diagnosed cancer in males in the world. Plasma quantification of prostate-specific antigen substantially improved the early detection of prostate cancer, but still lacks the required specificity. Clinical management of prostate cancer needs advances in the development of new non-invasive biomarkers, ameliorating current diagnosis and prognosis and guiding therapeutic decisions. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the post-transcriptional level. These miRNAs are expressed in the cells and are also present in cell-derived extracellular vesicles such as exosomes. Exosomes have been shown to act as mediators for cell to cell communication because of the regulatory functions of their content. High levels of exosomes are found in several body fluids from cancer patients and could be a potential source of non-invasive biomarkers. In this review, we summarize the diagnostic and prognostic utility of exosomal miRNAs in prostate cancer (AU)

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Exosomal microRNAs in liquid biopsies: future biomarkers for prostate cancer.

Prostate cancer is the second most diagnosed cancer in males in the world. Plasma quantification of prostate-specific antigen substantially improved the early detection of prostate cancer, but still lacks the required specificity. Clinical management of prostate cancer needs advances in the development of new non-invasive biomarkers, ameliorating current diagnosis and prognosis and guiding therapeutic decisions. microRNAs (miRNAs) are a class of small non-coding RNAs that regulate gene expression at the post-transcriptional level. These miRNAs are expressed in the cells and are also present in cell-derived extracellular vesicles such as exosomes. Exosomes have been shown to act as mediators for cell to cell communication because of the regulatory functions of their content. High levels of exosomes are found in several body fluids from cancer patients and could be a potential source of non-invasive biomarkers. In this review, we summarize the diagnostic and prognostic utility of exosomal miRNAs in prostate cancer.

Repetition of the rapid antigen test in initially negative supposed streptococcal pharyngitis is not necessary in adults.

AIMS: To determine whether the repetition of the rapid antigen detection test (RADT) in patients, with a high suspicion of presenting pharyngitis by group A beta-haemolytic streptococci (GABHS), with a previously negative test improves the validity of the test. METHODS: Two hundred and twenty-two patients aged 14 years or more with acute pharyngitis and two or more Centor criteria--tonsillar exudates, fever, tenderness in the lymph glands and/or absence of cough--were consecutively recruited. In all patients, a pharyngotonsillar sample was obtained with two swabs, one for the RADT (OSOM Strep A Genzyme test, Genzyme Diagnostics, Cambridge, MA, USA) and the other was sent to the Department of Microbiology for culture. In patients with a negative RADT, the determination was repeated. The sensitivity, specificity and predictive values were determined. RESULTS: Cultures were positive for GABHS in 55 patients (24.8%). Three false-negatives and 14 false-positives were observed by comparing the rapid test with throat culture, achieving a sensitivity of 94.5% and a specificity of 91.6%. Positive and negative predictive values were 78.8% and 98.1% respectively. Taking the second determination in the negative cases into account, the results were 96.4%, 91.6%, 79.1% and 98.7% respectively. CONCLUSIONS: The negative predictive value achieved with the RADT determination was very high. Repetition of the test only slightly improved this percentage, making repetition of this test unnecessary.

Functional analysis of regulatory elements controlling the expression of the ecdysone-regulated Drosophila ng-1 gene.

The steroid hormone ecdysone controls multiple aspects of insect development, including larval moults and metamorphosis, and can induce specific genetic responses in different tissues. The definition of the molecular mechanisms able to mediate this tissue-specific responsiveness may greatly contribute to understanding how such an accurate genetic response is achieved. In this work we have identified, by transgenic analysis, the regulatory elements directing the expression of ng-1, an ecdysone-regulated Drosophila gene showing a highly specific developmental expression profile. Our results show that an ecdysone-responsive element located within the ng-1 coding region is necessary for high-level gene expression, whereas the gene's spatial and temporal expression profile is fully controlled by a distinct upstream regulatory region. This region binds a set of transcriptional factors, including the FKH regulatory protein, which can potentially modulate the ecdysone genetic regulated response.

Cross-talking among Drosophila nuclear receptors at the promiscuous response element of the ng-1 and ng-2 intermolt genes.

In Drosophila, peaks of the titer of the steroid hormone ecdysone act as molecular signals that trigger all the major developmental transitions occurring along the life cycle. The EcR/USP heterodimer, known to constitute the functional ecdysone receptor, binds with high affinity to specific target sequences, the ecdysone response elements (EcREs), whose repertoire still remains to be fully characterized at both the molecular and functional levels. In order to investigate the properties of EcREs composed of directly repeated half-sites (DRs), we have analysed the binding properties of the ng-EcRE, a DR element located within the coding region of ng-1 and ng-2, two highly homologous genes mapping at the ecdysone-regulated 3C intermolt puff. We report here that the ng-EcRE contacts the ecdysone receptor through its directly repeated half-sites spaced by 12 bp, and that this element may interact efficiently with at least three Drosophila orphan receptors, namely DHR38, DHR39 and beta FTZ-F1. Interestingly, DHR38 is bound alone or in combination with USP, providing the first evidence that the EcR-USP and DHR38-USP may directly compete for binding to a common response element. These results suggest that EcREs composed of widely spaced DRs may contribute to the establishment of extensive nuclear receptors cross-talking along the development, a mechanism that might play a relevant role in determining the temporal and spatial specificity of the ecdysone response. Finally, we show that the ng-EcRE can promote functional interactions in vitro as well as in vivo, acting as a transcriptional enhancer able to confer a specific developmental expression profile to a minimal promoter in transgenic flies.

The moulting hormone ecdysone is able to recognize target elements composed of direct repeats.

In Drosophila melanogaster, three temporally distinct ecdysone-responsive puff sets, the so-called intermoult, early and late puffs, have been described on the salivary gland polytene chromosomes. We have analyzed in detail a DNA segment of the 3C polytene region, from which the originates one of the most prominent intermoult puffs, with the aim of identifying ecdysone response elements (EcREs). Here we report that two putative EcREs of identical sequence are located at this puff site. Interestingly, these elements display a novel structural feature, being composed of directly repeated half-sites. Our results show that the EcR/USP heterodimer known to constitute the ecdysone functional receptor complex is able to bind to and transactivate through target elements composed of directly repeated half-sites. In addition, we show that these elements are also able to bind efficiently USP alone, suggesting that USP and EcR/USP could compete for their binding to DNA.

The role of the BR-C locus on the expression of genes located at the ecdysone-regulated 3C puff of Drosophila melanogaster.

During the third larval instar, the steroid moulting hormone ecdysone activates three temporally distinct puff sets on the D. melanogaster salivary gland polytene chromosome: the so-called intermoult, early and late puffs. Hormonal regulation of intermoult puffs is quite complex and, so far, largely not understood. In order to further investigate this aspect, we have analysed the effects of mutations in a key regulator of the ecdysone response at the onset of metamorphosis, the Broad-Complex (BR-C) locus, on the expression of genes mapping at the 3C intermoult puff. On the basis of an accurate examination of 3C intermoult gene activity in single, carefully staged, third instar larvae of wild-type and BR-C mutant strains, we were able to subdivide these genes into two groups. Each group is characterised by a different temporal expression profile, so that at the beginning of the wandering stage the transcription of the first group declines as group II transcription is induced. Interestingly, the BR-C locus appears to play a regulatory role in establishing this transcriptional switch. By using mutants of each of the three lethal complementation groups, we precisely defined the role of BR-C functions in this developmental transition and we show that this locus also plays an essential role in the early pre-metamorphic hormonal response.

Dense cluster of genes is located at the ecdysone-regulated 3C puff of Drosophila melanogaster.

The 3C11-12 polytene bands of the Drosophila melanogaster X chromosome give rise to a prominent puff, whose regression is triggered by the increase in the titre of the steroid hormone 20-hydroxyecdysone occurring before the metamorphosis. Here, we report the molecular characterization of three genes, named ng-2, ng-3 and ng-4, which we found to be closely linked to each other and to Sgs-4, Pig-1 and ng-1, three other genes previously mapped at this polytene region. All six genes are, in fact, arranged in a tightly linked cluster spanning a DNA segment of only 11 kb. With the exception of ng-4, all the clustered genes are highly expressed only during the larval life and share the same tissue-specificity, being mainly transcribed within the salivary glands. In addition, two members of the cluster, ng-1 and ng-2, show a very high degree of sequence homology, clearly indicating that they are related to each other by means of a duplication event. Interestingly to note, the entire cluster shows a peculiar genomic location, extending across two introns of the memory gene dunce, a large gene of Drosophila whose organization has proved to be remarkably complex.

Effect of ecd1 mutation on the expression of genes mapped at the Drosophila melanogaster 3C11-12 intermoult puff.

The Drosophila melanogaster ecd1 mutation causes a severe temperature-sensitive deficiency in the titre of the steroid hormone ecdysone. This mutation was used to investigate the role of ecdysone in both the transcription of the genes mapped at the 3C11-12 intermoult puff region and the puff formation. Thoroughly synchronized ecd1 larvae were shifted to the non-permissive temperature at various times of the development; after 24 or 48 h, the levels of the transcripts derived from Sgs-4, Pig-1 and ng-1, the three genes located at the 3C11-12 polytene bands, were determined. The results showed that the levels of the transcripts encoded by Pig-1 and ng-1 are unaffected by the drop in the ecdysone titre occurring in non-permissive conditions whereas the amount of Sgs-4 mRNA is greatly reduced. These data clearly indicate that transcription of the three genes mapped within the puff region is affected differently by the hormone. Furthermore, ecd1 larvae cultured at the non-permissive temperature show a prominent puff at the 3C11-12 polytene bands, indicating that ecdysone is not essential for puff induction and that puff size is not simply correlated with high-level Sgs-4 transcription.

National case-control study of Kaposi's sarcoma and Pneumocystis carinii pneumonia in homosexual men: Part 1. Epidemiologic results.

To identify risk factors for the occurrence of Kaposi's sarcoma and Pneumocystis carinii pneumonia in homosexual men, we conducted a case-control study in New York City, San Francisco, Los Angeles, and Atlanta. Fifty patients (cases) (39 with Kaposi's sarcoma, 8 with pneumocystis pneumonia, and 3 with both) and 120 matched homosexual male controls (from sexually transmitted disease clinics and private medical practices) participated in the study. The variable most strongly associated with illness was a larger number of male sex partners per year (median, 61 for patients; 27 and 25 for clinic and private practice controls, respectively). Compared with controls, cases were also more likely to have been exposed to feces during sex, have had syphilis and non-B hepatitis, have been treated for enteric parasites, and have used various illicit substances. Certain aspects of a lifestyle shared by a subgroup of the male homosexual population are associated with an increased risk of Kaposi's sarcoma and pneumocystis pneumonia.