Overexpression of Wild-Type Human Alpha-Synuclein Causes Metabolism Abnormalities in Thy1-aSYN Transgenic Mice

Parkinson’s disease is a progressive neurodegenerative disorder characterized by loss of dopaminergic neurons, pathological accumulation of alpha-synuclein and motor symptoms, but also by non-motor symptoms. Metabolic abnormalities including body weight loss have been reported in patients and could precede by several years the emergence of classical motor manifestations. However, our understanding of the pathophysiological mechanisms underlying body weight loss in PD is limited. The present study investigated the links between alpha-synuclein accumulation and energy metabolism in transgenic mice overexpressing Human wild-type (WT) alpha-synuclein under the Thy1 promoter (Thy1-aSYN mice). Results showed that Thy1-aSYN mice gained less body weight throughout life than WT mice, with significant difference observed from 3 months of age. Body composition analysis of 6-month-old transgenic animals showed that body mass loss was due to lower adiposity. Thy1-aSYN mice displayed lower food consumption, increased spontaneous activity, as well as a reduced energy expenditure compared to control mice. While no significant change in glucose or insulin responses were observed, Thy1-aSYN mice had significantly lower plasmatic levels of insulin and leptin than control animals. Moreover, the pathological accumulation of alpha-synuclein in the hypothalamus of 6-month-old Thy1-aSYN mice was associated with a down-regulation of the phosphorylated active form of the signal transducer and activator of transcription 3 (STAT3) and of Rictor (the mTORC2 signaling pathway), known to couple hormonal signals with the maintenance of metabolic and energy homeostasis. Collectively, our results suggest that (i) metabolic alterations are an important phenotype of alpha-synuclein overexpression in mice and that (ii) impaired STAT3 activation and mTORC2 levels in the hypothalamus may underlie the disruption of feeding regulation and energy metabolism in Thy1-aSYN mice.

RNA-binding disturbances as a continuum from spinocerebellar ataxia type 2 to Parkinson disease

CAG triplet expansions in Ataxin-2 gene (ATXN2) cause spinocerebellar ataxia type 2 and have a role that remains to be clarified in Parkinson's disease (PD). To study the molecular events associated with these expansions, we sequenced them and analyzed the transcriptome from blood cells of controls and three patient groups diagnosed with spinocerebellar ataxia type 2 (herein referred to as SCA2c) or PD with or without ATXN2 triplet expansions (named SCA2p). The transcriptome profiles of these 40 patients revealed three main observations: i) a specific pattern of pathways related to cellular contacts, proliferation and differentiation associated with SCA2p group, ii) similarities between the SCA2p and sporadic PD groups in genes and pathways known to be altered in PD such as Wnt, Ephrin and Leukocyte extravasation signaling iii) RNA metabolism disturbances with "RNA-binding" and "poly(A) RNA-binding" as a common feature in all groups. Remarkably, disturbances of ALS signaling were shared between SCA2p and sporadic PD suggesting common molecular dysfunctions in PD and ALS including CACNA1, hnRNP, DDX and PABPC gene family perturbations. Interestingly, the transcriptome profiles of patients with parkinsonian phenotypes were prevalently associated with alterations of translation while SCA2c and PD patients presented perturbations of splicing. While ATXN2 RNA expression was not perturbed, its protein expression in immortalized lymphoblastoid cells was significantly decreased in SCA2c and SCA2p versus control groups assuming post-transcriptional biological perturbations. In conclusion, the transcriptome data do not exclude the role of ATXN2 mutated alleles in PD but its decrease protein expression in both SCA2c and SCA2p patients suggest a potential involvement of this gene in PD. The perturbations of "RNA-binding" and "poly(A) RNA-binding" molecular functions in the three patient groups as well as gene deregulations of factors not yet described in PD but known to be deleterious in other neurological conditions, suggest the existence of RNA-binding disturbances as a continuum between spinocerebellar ataxia type 2 and Parkinson's disease.

Xenopus laevis as a Model to Identify Translation Impairment

Protein synthesis is a fundamental process to gene expression impacting diverse biological processes notably adaptation to environmental conditions. The initiation step, which involves the assembly of the ribosomal subunits at the mRNA initiation codon, involved initiation factor including eIF4G1. Defects in this rate limiting step of translation are linked to diverse disorders. To study the potential consequences of such deregulations, Xenopus laevis oocytes constitute an attractive model with high degrees of conservation of essential cellular and molecular mechanisms with human. In addition, during meiotic maturation, oocytes are transcriptionally repressed and all necessary proteins are translated from preexisting, maternally derived mRNAs. This inexpensive model enables exogenous mRNA to become perfectly integrated with an effective translation. Here is described a protocol for assessing translation with a factor of interest (here eIF4G1) using stored maternal mRNA that are the first to be polyadenylated and translated during oocyte maturation as a physiological readout. At first, mRNA synthetized by in vitro transcription of plasmids of interest (here eIF4G1) are injected in oocytes and kinetics of oocyte maturation by Germinal Vesicle Breakdown detection is determined. The studied maternal mRNA target is the serine/threonine-protein-kinase mos. Its polyadenylation and its subsequent translation are investigated together with the expression and phosphorylation of proteins of the mos signaling cascade involved in oocyte maturation. Variations of the current protocol to put forward translational defects are also proposed to emphasize its general applicability. In light of emerging evidence that aberrant protein synthesis may be involved in the pathogenesis of neurological disorders, such a model provides the opportunity to easily assess this impairment and identify new targets.

[Infantile hemangioma: a new indication for propranolol? Retrospective study: a case-series of 25 infants]

BACKGROUND

In 2008, the New England Journal of Medicine reported a new indication for propranolol: treatment of complicated infantile hemangioma (IH). The objective of this study is to identify any adverse events and to measure the efficacy of propranolol in children with complicated IH, through a retrospective, observational, case-series study of 25 patients treated with propranolol at the Hôpital Universitaire des Enfants Reine Fabiola in Belgium.

OBSERVATIONS

25 patients were submitted to this therapy. The treatment was stopped prematurely for two of them, by parental fear of side effects and 48 % presented one or more adverse events; all of which were transient and rapidly controlled by adjusting the doses administered. Mean age at the start of treatment was 4,8 months. A clearly favorable response was observed in 100 % of patients at their first visit after treatment initiation ; a total response was seen in 9 patients, with subtotal and partial responses observed in 9 and 3 patients, respectively, by the end of treatment.

CONCLUSION

The real efficacy of propranolol for complicated IH was confirmed by the clearly evident improvement observed in all patients and the absence of non-responders. As global tolerance was also good, propranolol can therefore be considered to be an appropriate first- line treatment for complicated IH.

Feasibility and acceptability of HIV screening through the use of rapid tests by general practitioners in a Brussels area with a substantial African community

OBJECTIVES

To assess:1) if HIV screening with rapid tests in neighbourhoods with a substantial African community is feasible and acceptable among GPs and patients; 2) HIV seroprevalence.

METHODS

Multicenter prospective study with 10 trained physicians. Use of HIV standard test and INSTI Ultrarapid test.

INCLUSION CRITERIA

MSM, sex worker, multiple sexual partners, having returned or coming from a country with high HIV prevalence, IVDU, Indicator conditions as defined by HIV Indicator Diseases across Europe Study, having an AIDS-defining illness, having had a recent pregnancy or abortion; or presenting other risks.

RESULTS

From August 2010 to August 2011, 10 trained GPs offered an HIV test to 224 patients: 51% ♀, 48% ♂, 43% Caucasians, 45% Africans.

INCLUSION CRITERIA

32% "high risk group", 9% returning from an endemic country, 29% with an indicator condition; 12 patients (6%) refused the standard test. The INSTI was offered to 217(97%), 197 performed with 2 reactive rapid tests confirmed. The seroprevalence according to ethnic origin was 0% among Caucasians and 2.2% among Africans and was 1.5% among patients with an indicator condition. 1087 consecutive consultations of the same GPs were recorded: 42% patients had ≥ 1 inclusion criteria among which 41% of offered tests, that is to say 59% of "missed opportunities". The reasons for not offering the test as recorded for 55% of patients:"not indicated" 44.5%, "no time" 33%, "impossible to propose" 15%, test completed previously 11%, known HIV-positive 4%.

CONCLUSIONS

Standard and rapid tests are well received by patients but were usually not offered by doctors who have been trained.

[Infantile hemangioma and propranolol: a therapeutic "revolution". Literature review]

Infantile hemangioma (IH) is the most common benign vascular tumour affecting children. Most infantile hemangiomas are self-limiting, but some require specific treatment. Propranolol has been proposed for the treatment of infantile hemangiomas. The aim of this study is to explore the mechanism of action of propranolol for the treatment of infantile hemangiomas and to demonstrate its safety and efficacy through a review of the literature. The non cardioselective bêta-blocker propranolol has been used in a pediatric setting for 40 years and, since 2008, has a new indication. A clearly significant improvement has been observed in the condition of children with complicated IH (10%) treated with propranolol. This new indication has been widely described in the international literature. Various explanations have been put forward for the mechanism of action including a vasoconstrictor, antiangiogenic and apoptotic effect of propranolol on the different cells making up an IH. Overall tolerance is good and the efficacy markedly superior to that of any other treatments used for this purpose. In conclusion, with its good tolerance profile and superior efficacy versus all the other available therapies, propranolol can be considered to be a first-line treatment for complicated IH.

[Management of patients with HIV/AIDS by the general practitioner]

Dealing with HIV/AIDS in primary care encompasses preventive, curative, social and psychological aspects within a framework of a person-centred approach. Antiretroviral treatments enable the control of HIV infection, prevent opportunistic infections, reduce the risk of the sexual transmission and allow patients to "live their life" with an increased life expectancy, active sexuality and need to procreate. The holistic care of patients should always be the primary concern. An increased involvement of GP's in HIV care can raise the quality of care, reduce the stigma and prejudice surrounding HIV. Medical care providers can substantially affect HIV transmission by positively reinforcing changes to safe behavior, by referring patients for specialized services and working in direct collaboration with them, by facilitating partner counselling and testing. It might be considered to create a "path of HIV care" in the perspective of an optimal collaboration between primary care and specialists. However, providers must interweave the" half-baked "science about drug therapies, side effects and drug interactions with the psychosocial and lifestyle factors of the patient. Sometimes it's not easy to find adequate and relevant information about HIV in primary care. This document will provide primary care givers the keys for improvement, increase their basic HIV-related skills (and strengthen their role in HIV/AIDS prevention and follow-up) and make them more confident in their assessments.

[The new types of addiction]

Addiction is characterized by the inability to control his consumption of product or control certain behaviors, and the continuation of the behavior despite knowledge of its adverse effects. Addictions to substances like heroin, cocaine, etc., are well known. But other substances potentially addictive are getting more common in Belgium: MDMA, GHB / GBL, Cristal, etc. The existence of addictions without substance (called also behavioral addiction) is well recognized now: gambling addiction seems to be the most common and has been recognized as a disease by WHO, but we can also observe cyberaddiction, addiction to sex, workalholic, addiction to shopping, etc. The screening of poly-addiction or to one substance or one behavior should be systematized in the history of every patient. This screening should be facilitated through the development and validation of a cross scale. Particular attention will be paid to certain groups, both in primary prevention and screening: men, adolescents and young adults, university students or high schools, clubbers, sporting people, prisoners, ethnic minorities, people with mental disorders like depression. Primary care workers, and especially general practitioners, are at the first place to detect those different forms of addiction, can affort appropriate care according to patient's characteristics and type addiction, and to identify high-risk situations for relapse.

[Antibiotics in current infections]

Our principal concerns about the antibiotic regulation is the emergence and the increase in bacterial resistances to antibiotics. This article discusses the various factors influencing this resistance and the various indications of antibiotics in current infections in general practice. In our singular conference with the patient, we have to integrate the characteristics of the patient, the clinical exams and the evidence of the literature to reach a clinical expertise allowing us to better prescription of antibiotics and thus to reduce the pressure of selection exerted on the bacteria.

[Evaluation of the vaccine coverage of the general practitioners in the French Community]

The present inter-University study aims to analyze the vaccine statute of the Belgian French-speaking general practionners and the reasons of their possible non-vaccination. A questionnaire with an exhaustive list of vaccines was sent by postal way to a random sample of thousand two hundred and twenty general practitioners. The results were analyzed via SPSS 13. The rate of answer is 60.83%. Two thirds of the doctors (67%) considered themselves in order of vaccination anti-influenza. A majority of doctors (59.7%) is vaccinated systematically each year. The majority of the doctors (83%) considered themselves in antitetanus order of vaccination. Two thirds (67%) think that the vaccine protects from 5 to 10 years. Nearly 73% of the doctors considered themselves in order of vaccination against hepatitis B. More than 50% of the doctors received a vaccine HBV since less than 10 years. The majority of the doctors (79.2%) made a blood control of their protection after vaccination HBV Almost half of the doctors thinks that the vaccine protect for life, 23% from 10 to 20 years and 14% from 5 to 10 years. Two thirds (67%) of the doctors did not make a vaccine against rubella. In 80% of the cases vaccination dated from more than 20 years. In nearly two thirds of the cases the doctors did not make blood control of their protection. Nearly 60% of the questioned doctors think that vaccination offers a protection to life. About half of the doctors did not consider themselves in order of vaccination against the whooping-cough. In three quarter of the cases last vaccination dated from more than 20 years. The two principal durations of protection of the vaccine are with life and between 10 and 20 years. Three quarters of the questioned doctors are considered in order of vaccination against the poliomyelitis. However in 62% of the cases the last vaccine goes up with more than 20 years. More two thirds of the doctors think than the vaccine protects with life or from 10 to 20 years. Two thirds of doctors considered themselves in order of vaccination against the diphteria. For a third of the doctors the vaccine dated from less than 5 years, in more than one quarter of the cases to more than 20 years like between 5 and 10 years. About half of the doctors said they were vaccinated against other pathologies: hepatitis A (34.5%), the yellow fever (21.1%), the thyphoid fever (12.5%), the BCG (8.9%), the pneumococcus (6.6%), meningitis and variola (5%). In the French Community, the vaccine coverage of the general practitioners against the influenza (67%), tetanus (83%) and hepatitis B (73%) is, in this study, higher or equal to the other Belgian and international studies but remains insufficient. A bad vaccine coverage is observed concerning rubella, the whooping-cough, the poliomyelitis. The answers over the durations of protection of the vaccines are rather disparate and show a bad knowledge of these durations and diagrams of vaccination. An update of this knowledge could be carried out during the continuous medical trainings.

[Global HIV care in general/family practice]

Dealing with HIV/AIDS in primary care encompasses preventive, curative, social and psychological aspects within a framework of a person-centred approach. Antiretroviral treatments enable the control of HIV infection, prevent opportunistic infections and allow patients to "live their life" with an increased life expectancy, active sexuality and need to procreate. The holistic care of patients should always be the primary concern. An increased involvement of GP's in HIV care can raise the quality of care, reduce the stigma and prejudice surrounding HIV Medical care providers can substantially affect HIV transmission by positively reinforcing changes to safe behavior, by referring patients for specialized services and working in direct collaboration with them, by facilitating partner counseling and testing. However, providers must interweave the "half-baked "science about drug therapies, side effects and drug interactions with the psychosocial and lifestyle factors of the patient. Sometimes it's not easy to find adequate and relevant information about HIV in primary care. This document will provide primary care givers the keys for improvement, increase their basic HIV-related skills (and strengthen their role in HIV/AIDS prevention and follow-up) and make them more confident in their assessments.

[Vaccination of general practitioners]

The vaccination of general practitioners represents significant problems for two reasons: they can be a reservoir of infectious diseases for the patients they are in contact with and their attitudes towards vaccination can influence their preventative acts and consequently the vaccination coverage of the population. The anti-influenza vaccination of the care providers is associated with a decrease of mortality amongst patients. Hepatitis B is one of the most frequent professional occupational infectious diseases and vaccination is necessary for all the professionals at risk. Concerning the whooping-cough we can observe at the present time an increase in the number of cases. The "Conseil Supérieur d'Hygiène" advises to propose vaccination of the people in contact with infants and people who have not HAD vaccination supplements in childhood. The rubella vaccination for unprotected women is also recommended for the care providers, to avoid the risk of infection and the possible implications for the foetus. The existing data in Belgium on the vaccination coverage of general practitioners is poor, but leads us to believe there is an insufficient vaccination coverage against these diseases. A study will shortly be undertaken to analyze the vaccination status of the Belgian French-speaking doctors and to further analyse their reasoning for any possible non-vaccination.

Rheumatic manifestations due to human parvovirus B19. A report of four cases

Human parvovirus B19 has been incriminated in the genesis of hematologic, dermatologic, neurologic, and rheumatic disorders. We report four cases in which inflammatory rheumatic manifestations developed during the course of human parvovirus B19 infection documented by the presence of IgM and IgG antibodies. There was one case each of monoarthritis, oligoarthritis, polyarthritis, and enthesitis. Three patients had a favorable outcome under nonsteroidal antiinflammatory drug therapy, and one developed reflex sympathetic dystrophy syndrome. In patients with inflammatory rheumatic manifestations that do not fit any specific diagnosis, a careful family history can provide evidence suggesting human parvovirus B19 infection, which should be confirmed by tests for IgM and IgG antibodies.