Circadian glucocorticoid oscillations preserve a population of adult hippocampal neural stem cells in the aging brain.

A decrease in adult hippocampal neurogenesis has been linked to age-related cognitive impairment. However, the mechanisms involved in this age-related reduction remain elusive. Glucocorticoid hormones (GC) are important regulators of neural stem/precursor cells (NSPC) proliferation. GC are released from the adrenal glands in ultradian secretory pulses that generate characteristic circadian oscillations. Here, we investigated the hypothesis that GC oscillations prevent NSPC activation and preserve a quiescent NSPC pool in the aging hippocampus. We found that hippocampal NSPC populations lacking expression of the glucocorticoid receptor (GR) decayed exponentially with age, while GR-positive populations decayed linearly and predominated in the hippocampus from middle age onwards. Importantly, GC oscillations controlled NSPC activation and GR knockdown reactivated NSPC proliferation in aged mice. When modeled in primary hippocampal NSPC cultures, GC oscillations control cell cycle progression and induce specific genome-wide DNA methylation profiles. GC oscillations induced lasting changes in the methylation state of a group of gene promoters associated with cell cycle regulation and the canonical Wnt signaling pathway. Finally, in a mouse model of accelerated aging, we show that disruption of GC oscillations induces lasting changes in dendritic complexity, spine numbers and morphology of newborn granule neurons. Together, these results indicate that GC oscillations preserve a population of GR-expressing NSPC during aging, preventing their activation possibly by epigenetic programming through methylation of specific gene promoters. Our observations suggest a novel mechanism mediated by GC that controls NSPC proliferation and preserves a dormant NSPC pool, possibly contributing to a neuroplasticity reserve in the aging brain.

Associated arterial and venous cerebral manifestations in Behçet's disease.

Behçet's disease is a rare multisystemic vasculitis with an etiology that is still unknown. Neurological manifestations may be seen in approximately 5-15% of patients, and both parenchymal and extraparenchymal neurological involvement has been described. When cerebral venous thrombosis (CVT) is the main extraparenchymal manifestation of Behçet's disease, the condition is then dubbed "angio-Behçet's syndrome". However, arterial involvement is extremely rare, with only one reported case of vasculo-neuro-Behçet's disease, characterized by both venous and intracranial arterial involvement - until now. This report is of two patients diagnosed with Behçet's disease characterized by the concomitant presence of both cerebral arterial manifestations and CVT.

Configurations of the Re-scan Confocal Microscope (RCM) for biomedical applications.

The new high-sensitive and high-resolution technique, Re-scan Confocal Microscopy (RCM), is based on a standard confocal microscope extended with a re-scan detection unit. The re-scan unit includes a pair of re-scanning mirrors that project the emission light onto a camera in a scanning manner. The signal-to-noise ratio of Re-scan Confocal Microscopy is improved by a factor of 4 compared to standard confocal microscopy and the lateral resolution of Re-scan Confocal Microscopy is 170 nm (compared to 240 nm for diffraction limited resolution, 488 nm excitation, 1.49 NA). Apart from improved sensitivity and resolution, the optical setup of Re-scan Confocal Microscopy is flexible in its configuration in terms of control of the mirrors, lasers and filters. Because of this flexibility, the Re-scan Confocal Microscopy can be configured to address specific biological applications. In this paper, we explore a number of possible configurations of Re-scan Confocal Microscopy for specific biomedical applications such as multicolour, FRET, ratio-metric (e.g. pH and intracellular Ca2+ measurements) and FRAP imaging.

Efficacy of anti-TNF alpha in severe and/or refractory Behçet's disease: Multicenter study of 124 patients.

OBJECTIVE: To report the efficacy and safety of anti-TNF agents in patients with severe and/or refractory manifestations of Behçet's disease (BD). METHODS: We performed a multicenter study of main characteristics and outcomes of anti-TNF alpha treatments [mainly infliximab (62%), and adalimumab (30%)] in 124 BD patients [48% of men; median age of 33.5 (28-40) years]. RESULTS: Overall response (i.e. complete and partial) rate was 90.4%. Clinical responses were observed in 96.3%, 88%, 70%, 77.8%, 92.3% and 66.7% of patients with severe and/or refractory ocular, mucocutaneous, joint, gastro-intestinal manifestations, central nervous system manifestations and cardiovascular manifestations, respectively. No significant difference was found with respect to the efficacy of anti-TNF used as monotherapy or in association with an immunosuppressive agent. The incidence of BD flares/patient/year was significantly lower during anti-TNF treatment (0.2 ± 0.5 vs 1.7 ± 2.4 before the use of anti-TNF, p < 0.0001). The prednisone dose was significantly reduced at 6 and 12 months (p < 0.0001). In multivariate analysis, retinal vasculitis was negatively associated with complete response to anti-TNF (OR = 0.33 [0.12-0.89]; p = 0.03). The efficacy and relapse free survival were similar regardless of the type of anti-TNF agent used. After a median follow-up of 21 [7-36] months, side effects were reported in 28% of patients, including infections (16.3%) and hypersensitivity reactions (4.1%). Serious adverse events were reported in 13% of cases. CONCLUSION: Anti-TNF alpha therapy is efficient in all severe and refractory BD manifestations. Efficacy appears to be similar regardless of the anti-TNF agent used (infliximab or adalimumab).

Cannabinoid type 2 receptor inhibition enhances the antidepressant and proneurogenic effects of physical exercise after chronic stress.

Chronic stress is a major risk factor for neuropsychiatric conditions such as depression. Adult hippocampal neurogenesis (AHN) has emerged as a promising target to counteract stress-related disorders given the ability of newborn neurons to facilitate endogenous plasticity. Recent data sheds light on the interaction between cannabinoids and neurotrophic factors underlying the regulation of AHN, with important effects on cognitive plasticity and emotional flexibility. Since physical exercise (PE) is known to enhance neurotrophic factor levels, we hypothesised that PE could engage with cannabinoids to influence AHN and that this would result in beneficial effects under stressful conditions. We therefore investigated the actions of modulating cannabinoid type 2 receptors (CB2R), which are devoid of psychotropic effects, in combination with PE in chronically stressed animals. We found that CB2R inhibition, but not CB2R activation, in combination with PE significantly ameliorated stress-evoked emotional changes and cognitive deficits. Importantly, this combined strategy critically shaped stress-induced changes in AHN dynamics, leading to a significant increase in the rates of cell proliferation and differentiation of newborn neurons, overall reduction in neuroinflammation, and increased hippocampal levels of BDNF. Together, these results show that CB2Rs are crucial regulators of the beneficial effects of PE in countering the effects of chronic stress. Our work emphasises the importance of understanding the mechanisms behind the actions of cannabinoids and PE and provides a framework for future therapeutic strategies to treat stress-related disorders that capitalise on lifestyle interventions complemented with endocannabinoid pharmacomodulation.

Traumatic brain injury promotes neurogenesis at the cost of astrogliogenesis in the adult hippocampus of male mice.

Traumatic brain injury (TBI) can result in long-lasting changes in hippocampal function. The changes induced by TBI on the hippocampus contribute to cognitive deficits. The adult hippocampus harbors neural stem cells (NSCs) that generate neurons (neurogenesis), and astrocytes (astrogliogenesis). While deregulation of hippocampal NSCs and neurogenesis have been observed after TBI, it is not known how TBI may affect hippocampal astrogliogenesis. Using a controlled cortical impact model of TBI in male mice, single cell RNA sequencing and spatial transcriptomics, we assessed how TBI affected hippocampal NSCs and the neuronal and astroglial lineages derived from them. We observe an increase in NSC-derived neuronal cells and a concomitant decrease in NSC-derived astrocytic cells, together with changes in gene expression and cell dysplasia within the dentate gyrus. Here, we show that TBI modifies NSC fate to promote neurogenesis at the cost of astrogliogenesis and identify specific cell populations as possible targets to counteract TBI-induced cellular changes in the adult hippocampus.

[Colchicine and non-severe ocular inflammation excluding Behcet's disease: 16 cases and literature review]. / Colchicine et inflammation oculaire non sévère hors maladie de Behcet : 16 cas et revue de la littérature.

INTRODUCTION: Colchicine is a narrow therapeutic margin drug that does not have the adverse effects of corticosteroids and immunosuppressants. Its use in non-severe ocular inflammatory disease excluding Behcet's disease has not been studied. METHODS: We included patients seen in the internal medicine department of Dijon University Hospital consecutively between September 2020 and September 2021 if they had received colchicine during their pathology. Patients with suspected Behçet's disease were excluded. Treatment efficacy was studied in patients with at least one year of disease progression who had received more than one year of colchicine. Successful treatment was defined as a 50 % reduction in the number of annual relapses on colchicine. RESULTS: Sixteen patients were included (9 women and 7 men). They had recurrent anterior uveitis (n=10), recurrent scleritis (n=5) and intermediate uveitis. Opthalmological involvement was neither severe nor complicated. All patients combined, the annual relapse ratio (ARR) decreased from 1.8 (0.8-3.5) to 0.3 (0-1.6), (P=0.06). Colchicine was considered effective in three of 10 analyzable patients. In only one patient, treatment was stopped for adverse effects after six weeks. CONCLUSION: In view of the interesting benefit-risk ratio of colchicine, it seems appropriate to focus on this molecule in non-granulomatous anterior uveitis and non-severe recurrent scleritis.

[Crohn's disease during the course of multiple sclerosis: role of interferon-beta therapy]. / Maladie de Crohn au cours d'une sclérose en plaques: rôle de l'interféron bêta.

Interferon-beta (IFN-beta) therapy can trigger immune adverse effects. We report a patient, who was treated for multiple sclerosis (MS) by IFN-beta during 3 years before developing a severe colitis due to Crohn's disease (CD). Neurological manifestations may occur in CD but rarely mimic MS. This report's points highlight the possible association of MS and CD, where IFN-beta therapy probably unmasked CD. Indeed, similar cases of CD flares have been reported after IFN-alpha therapy for chronic C hepatitis.

[Use of biotherapy in the management of Behçet's disease in a department of internal medicine]. / Recours à la biothérapie dans la prise en charge de la maladie de Behçet dans un service de médecine interne.

BACKGROUND: Behçet's disease (BD) is a recurrent multisystemic disease responsible for occlusive vasculitis with arterial, venous and capillary involvement. The aim of this study was to determine the frequency and the features associated with the use of biotherapy in the management of patients followed in our department for BD. METHODS: This is a retrospective study of patients medical records followed for BD in a department of internal medicine from January 2005 to August 2018. RESULTS: A total of 41 patients were included with a mean age at diagnosis of 42.5±12.1 years (range 16 to 63) and a sex ratio men/women of 1.05. Oral and/or genital aphtosis was present in 70.7% of the patients. Other lesions were: ocular (78.0%), articular (46.3%), cutaneous (41.5%), central neurological (34.1%), vascular (26.8%), digestive (7.3%), pericardial (2.4%) and epididymal (2.4%). A biotherapy, interferon α and monoclonal antibodies, was used in 15 patients (36.6%), after failure of conventional treatments. The monoclonal antibodies were anti-TNFα (infliximab, adalimumab, certolizumab and golimumab) except in one patient for whom ustekinumab was used. Biotherapy was used in 46.9% of the patients with ocular involvement and never used in those patients without ocular involvement (P=0.01). CONCLUSION: Biotherapy is effective and represents a solution to the failures of conventional treatments in severe forms of Behçet's disease with ocular involvement.

Insult-induced aberrant hippocampal neurogenesis: Functional consequences and possible therapeutic strategies.

Adult hippocampal neurogenesis plays a critical role in a wide spectrum of hippocampus-dependent functions. Brain pathologies that involve the hippocampus like epilepsy, stroke, and traumatic brain injury, are commonly associated with cognitive impairments and mood disorders. These insults can affect neural stem cells and the subsequent neurogenic cascade in the hippocampus, resulting in the induction of aberrant neurogenesis, which is thought to compromise hippocampal network function, thereby hampering hippocampus-dependent behavior. We here summarize recent preclinical literature on hippocampal insult-induced changes in neurogenesis and based on that, we propose that normalizing aberrant neurogenesis post-insult may help to prevent or rescue behavioral deficits which could help develop novel therapeutic strategies.

[Stroke in young adults with celiac disease]. / Accident vasculaire cérébral ischémique de l'adulte jeune au cours de la maladie coeliaque. A propos de deux observations.

INTRODUCTION: Celiac disease is a common condition with a prevalence of about 1%. Clinical extradigestive presentations are various and stroke can be one of the neurological manifestations. EXEGESIS: Two cases of stroke occurring in young adults are described, leading to the diagnosis of celiac disease. Hyperhomocysteinemia or cerebral arterial vasculopathy in one case and antiphospholipid syndrome in the other case are thought to be involved in the pathogenesis of stroke during celiac disease. CONCLUSION: The possible presence of celiac disease should be discussed in unexplained young adult stroke.

[Quality of life measures in SLE: An update]. / Mesures de qualité de vie au cours du lupus systémique : état des lieux, actualité et utilisation pratique.

Systemic lupus erythematosus (SLE) is a chronic disease that considerably hampers patient's daily living. Qualitative studies with patients' interviews have been conducted to describe the experiences and perspectives of adults living with SLE. Among existing generic and disease-specific quality of life (QOL) questionnaires, none succeeded to exhaustively measure patient's preoccupations. However, these tools are useful to quantify the burden of the disease. Social precariousness, socioeconomic status and education level are intimately correlated to QOL measures, either generic or disease-specific. Musculoskeletal disease activity is also associated with a lower QOL. Using disease-specific tools may be useful because of a better aptitude to record an improvement in health status. Moreover, using generic and disease-specific questionnaires together may help to identify factors associated with a lower quality of life but not related to SLE from the patient's perspective (such as smoking or obesity). Developing new ways of recording QOL data in the future may help to evaluate the real benefit of using QOL scales in daily practice.

[Management of orbital inflammation in internal medicine. Proposal for a diagnostic work-up]. / Orbitopathies inflammatoires. Que doit savoir l'interniste ?

Inflammatory orbitopathies relate to an inflammatory state originating within the orbit and its adnexes, except the inner ocular globe. Orbital inflammation (OI) may be either localized manifestation of a proven or like autoimmune disease, or local response from immune system against infectious, structural or tumoral antigens. We review the clinical manifestations of OI, which provide helpful clues to the diagnosis and describe the inflammatory, infectious and neoplastic conditions classically associated with OI. Autoimmune diseases are probably the most common causes of OI associated with a bilateral dacryoadenitis (e.g., sarcoidosis, granulomatosis with polyangiitis, IgG4-related disease). We focused on a major part of the IgG4-RD spectrum, the IgG4-related orbital disease which has been recently described and the idiopathic orbital inflammation syndrome that one should consider in patients 40 years of age or older with non specific inflammation OI on biopsy but without underlying local or systemic disease. An algorithm for the diagnostic approach of OI was proposed. If systemic explorations fail to diagnose an underlying disease, histopathologic control is required for distinguishing non-specific OI from other differential diagnosis, especially lymphoma. In the cases of pure myositic locations and posteriorly located tumours where biopsy could damage to the optic nerve, analysis of orbital lesions in T2W IRM sequence may be helpful to distinguish idiopathic OI (IOI) from lymphoma. When the diagnostic work-up fails, a corticosteroid trial could be used, but its beneficial effect has to be cautiously interpretated before definitively diagnosing IOI. Finally, treatments used in main infllammatory orbitopathies were also reviewed.

[Hyper-IgE in internal medicine]. / Hyper-IgE en médecine interne.

Hyper-IgE may be found under many pathological conditions. The role of IgE is essentially associated with the occurrence of allergic manifestations, which may be accompanied by an increase of their serum levels. Elevation of total IgE has also been reported in association with certain rare genetic immune deficiencies called hyper-IgE syndromes. Other circumstances such as infectious diseases, tumors or autoimmune diseases may also be accompanied by an excessive synthesis of IgE. Considering the diversity of these situations, discussion of the prognostic value of total IgE is useful to the internist.

[Ocular tuberculosis]. / Tuberculose oculaire.

Despite extensive investigations, including the use of Interferon-gamma release assays (IGRA), the diagnosis of intraocular tuberculosis (TB) remains challenging. Ocular evidence of Mycobacterium tuberculosis in low endemic countries for TB is extremely rare, leading mostly to a TB-related ocular inflammation presumptive diagnosis. This present work aims: to highlights the main clinical patterns suggestive of ocular TB; and the latest recommended guidelines for diagnosing ocular TB to clarify interferon-gamma release assay (IGRA) contribution and accuracy to the management of intraocular TB and its diagnosis, in addition to other available diagnostic tools, such as tuberculin skin test, bacteriologic and histologic analysis from intra/extra ocular sample and radiographic investigations; to define the accuracy of these diagnostic tools according to the endemic TB prevalence; and finally to identify therapeutic strategies adapted to the main clinical presentations of ocular TB. Our review of the literature shows that management of suspected ocular TB differs significantly based on whether patients are from high or low TB prevalence countries since accuracy of chest X-ray, tuberculin skin test and IGRA is significantly different. Taking into account these discrepancies, distinct guidelines should be determined for managing patients with suspected ocular TB, taking into consideration home prevalence of TB-patients.

[Uveitis: Diagnostic work-up. Recommendations from an expert committee]. / Prise en charge diagnostique des uvéites : recommandations d'un groupe d'experts.

INTRODUCTION: Diagnostic work-up of uveitis involves many uncertainties. Search for an etiology should take into account the epidemiology of uveitis and focus on the most severe diseases or those, which can be treated. This work was undertaken to establish recommendations for the diagnosis work-up of uveitis. METHODS: Recommendations were developed by a multidisciplinary panel of 15 experts, including internists, ophthalmologists and a rheumatologist and are based on a review of the literature with regard to effectiveness of investigations and the results of the ULISSE study, which is the first prospective study assessing the efficiency of a standardized strategy for the etiological diagnosis of uveitis. Children, immunocompromised patients, severe retinal vasculitis and specific ophthalmological entities are excluded from these recommendations. RESULTS: Investigations should be first guided by the history and physical examination. Serological screening for syphilis is the only test appropriate in all forms of uveitis. If no diagnosis is made after this stage, we propose investigations guided by the anatomic characteristics of uveitis. It includes HLA B27 testing (in unilateral acute anterior non-granulomatous uveitis), serum angiotensin converting enzyme, interferon-gamma release assay and chest CT (chronic uveitis), cerebral MRI and anterior chamber tap with IL10 analysis (intermediate or posterior uveitis in patients over 40 years). Investigations ordered in the absence of orientation are almost always unhelpful. CONCLUSIONS: We propose a strategy for the etiologic diagnosis of uveitis. The recommendations should be updated regularly. The efficiency of more invasive investigations has yet to be evaluated.

[Scleritis and systemic diseases: What should know the internist?] / Sclérites et maladies systémiques : que doit savoir l'interniste ?

Scleritis is an inflammatory disease of the sclera; outer tunic of the eye on which the oculomotor muscles are inserted. It can be associated with a systemic disease up to one time out of 3. These associated diseases are mainly rheumatoid arthritis, vasculitis, including granulomatosis with polyangiitis in the first line and spondyloarthropathies. Before mentioning such an etiology, it is necessary to eliminate an infectious cause, mainly herpetic, which is regularly underestimated. The classification of scleritis is clinical. We distinguish between anterior scleritis and posterior scleritis. Anterior scleritis is diffuse or nodular, usually of good prognosis. Anterior necrotizing scleritis with inflammation is often associated with an autoimmune disease, necrotizing scleritis without inflammation usually reflects advanced rheumatoid arthritis. The treatment of these conditions requires close collaboration between internists and ophthalmologists to decide on the use of corticosteroid therapy with or without immunosuppressors or biotherapies.

[Therapeutic strategy for the treatment of non-infectious uveitis proposed by an expert panel]. / Avis d'experts pour le traitement des uvéites non infectieuses.

Conventional immunosuppressive drugs, anti-TNF alpha and other biotherapies used in clinical practice are capable of controlling non-infectious anterior uveitis, posterior uveitis and panuveitis. The present work has been led by a multidisciplinary panel of experts, internists, rheumatologists and ophthalmologists and is based on a review of the literature. In case of corticodependency or sight-threatening disease, conventional immunosuppressive drugs (methotrexate, azathioprine and mycophenolate mofetil) and/or anti-TNF alpha (adalimumab, infliximab) are used to achieve and maintain remission. Interferon is an efficient immunomodulatory treatment, as a second-line therapy, for some therapeutic indications (refractory macular edema, Behçet's vascularitis). Other biologics, especially tocilizumab, are showing promising results. Local treatments (corticosteroids, sirolimus etc.) are adjuvant therapies in case of unilateral inflammatory relapse. Therapeutic response must be evaluated precisely by clinical examination and repeated complementary investigations (laser flare photometry, multimodal imaging, perimetry, electroretinography measures).

[Interest of cotrimoxazole in relapsing idiopathic anterior scleritis: about six cases]. / Intérêt du cotrimoxazole dans les sclérites antérieures idiopathiques récidivantes: à propos de six observations.

INTRODUCTION: Anterior scleritis is defined as an inflammation of the sclera, located anteriorly to the equator of the eye. Cotrimoxazole is an antibiotic with an immunomodulatory action. EXEGESIS: In case of idiopathic anterior scleritis or scleritis associated with autoimmune diseases, immunosuppressive treatment is often required. We report on six patients with anterior idiopathic scleritis non sensitive to local treatment where cotrimoxazole improved or cured the symptoms. CONCLUSION: Cotrimoxazole seems to be an interesting therapeutic treatment in non threatening anterior scleritis.

[Management of uveomeningitis in internal medicine: Proposal for a diagnostic work-up]. / Prise en charge diagnostique des uvéoméningites en médecine interne.

Uveomeningitis relates to an inflammatory state extending from iris and ciliary bodies to the choroid behind the eye. Because of a close contact between eye and brain, and barrier disruption, the inflammation can spread into the central nervous system (CNS). We review the clinical manifestations of uveitis, which are known to provide helpful clues to the diagnosis and describe the infectious, inflammatory, and neoplastic conditions classically associated with the uveomeningitis. Inflammatory or auto-immune diseases are probably the most common clinically recognized causes of uveomeningitis associated with a significant pleiocytosis. These entities often cause inflammation of various tissues in the body, including ocular structures and the meninges (i.e., sarcoidosis, Behçet's disease, and Vogt-Koyanagi-Harada syndrome). The association of an infectious uveitis with an acute or a chronic meningo-encephalitis is unusual but occasionally the eye examination may suggest an infectious etiology or even a specific organism responsible for an uveomeningitis. One should consider the diagnosis of primary ocular-CNS lymphoma in patients of 40 years of age or older with bilateral uveitis, especially with prominent vitritis, showing poor response to corticosteroid therapy. Finally, an algorithm for the diagnostic approach of uveomeningitis is proposed.