Investigating p62 Concentrations in Cerebrospinal Fluid of Patients with Dementia: A Potential Autophagy Biomarker In Vivo?

Several studies have revealed defects in autophagy in neurodegenerative disorders including Alzheimer's disease (AD) and frontotemporal dementia (FTD). SQSTM1/p62 plays a key role in the autophagic machinery and may serve as a marker for autophagic flux in vivo. We investigated the role of p62 in neurodegeneration, analyzing its concentrations in the CSF of AD and FTD patients. We recruited 76 participants: 22 patients with AD, 28 patients with FTD, and 26 controls. CSF p62 concentrations were significantly increased in AD and FTD patients when compared to controls, which persisted after adjusting for age (p = 0.01 and p = 0.008, respectively). In female FTD patients, p62 positively correlated with the neurodegenerative biomarkers t-Tau and p-Tau. A significant correlation between CSF p62 concentrations and several clinical features of AD was found. Our data show that p62 is increased in CSF of AD and FTD patients, suggesting a key role of autophagy in these two disorders. The levels of p62 in CSF may reflect an altered autophagic flux, and p62 could represent a potential biomarker of neurodegeneration.

G-CSF administration to adult mice stimulates the proliferation of microglia but does not modify the outcome of ischemic injury.

Recent evidence suggests that adult bone marrow stem cells reduce tissue damage and promote repair following CNS ischemic injury. Since granulocyte-colony stimulating factor (G-CSF) mobilizes hematopoietic stem cells to the circulating compartment, here we tested whether administration of this drug modifies the outcome of a permanent occlusion of the middle cerebral artery in adult mice. To elucidate the behavior and fate of blood-borne cells in the ischemic brain, we produced chimeric animals, in which hematopoietic derivatives are genetically tagged. G-CSF administration enhances the proliferation of microglia in the uninjured CNS but has no effect on the amount of hematopoietic cells that infiltrate the ischemic tissue and on the size of the lesion. The blood-borne elements acquire different mesodermal identities but fail to adopt neural phenotypes, even though they occasionally fuse with Purkinje neurons. These results indicate that G-CSF treatment does not exert a significant beneficial effect on the ischemic injury.

Delayed onset of a second paraneoplastic neurological syndrome in eight patients.

BACKGROUND: The occurrence of a second delayed paraneoplastic neurological syndrome (PNS), different from the first, in the same patient, is not well known. However, recognition of this possibility is important in the management of the patient with PNS. OBJECTIVE: To describe eight patients who presented with two different PNS with a time delay of months to years. DESIGN, SETTING AND PATIENTS: Retrospective analysis of eight patients, included in the European PNS database, with two different PNS that occurred months to years apart. RESULTS: The median delay between the two different PNS was 15 months. The antibody repertoire did not change between the two episodes. Anti-Hu was detected in five patients, and anti-CV2 and anti-Ri in one each. One patient did not present onconeural antibodies. Lung cancer was diagnosed in six patients. In five patients, the second PNS revealed a cancer relapse (n=4) or a second cancer (n=1) and in three it occurred without evidence of tumour recurrence. In these three patients, all with anti-Hu antibodies, the second episode consisted of a lower motor neuron disease. Median survival was not reached after a median follow-up of 5 years. CONCLUSIONS: A second PNS can reveal a cancer relapse but can also arise in its absence. The long survival of patients with a second PNS suggests that the immune response might be more effective in controlling the cancer.

Risk of cancer in patients with Guillain-Barré syndrome (GBS). A population-based study.

The possible relationship between Guillain-Barré syndrome (GBS) and cancer is still controversial and the existence of a paraneoplastic GBS remains unconfirmed. To better define whether there is a relationship between GBS and malignancy, we compared the observed and the expected number of patients with tumours in a population-based cohort of subjects with GBS. Clinical differences between GBS patients with or without malignancies were analysed. Data were obtained from the Piemonte and Valle d'Aosta Register for GBS (PARGBS) (years 1990-1998). GBS was diagnosed according to NINCDS criteria. The number of expected cases of malignancy in the PARGBS population was calculated using the incidence rate of all types of cancer (ICD codes 140-208) in Piemonte [1985-1987], and in the most important town of this region, that is Turin (years 1993-1997). In the nine-year period, 435 incident patients with GBS were found. Nine of them developed cancer in the six months preceding or following GBS; in seven of them, the diagnosis of cancer and GBS was concomitant. The expected number of malignant tumours was 3.7 (using the incidence in Piemonte) and 3.8 (using the incidence in Turin); therefore, the odds ratios were 2.43 (95 % CI, 1.11-4.62) and 2.37 (95% CI, 1.09-4.50), respectively (p<0.01). Although the cases with malignancies were clinically similar to the other cases of GBS observed through the Register, the mortality in GBS patients with cancer was higher and was the final cause of death in two patients affected by severe cancer. These results suggest a possible correlation between some cases of GBS and cancer. However, GBS in cancer patients does not meet all the criteria for paraneoplastic diseases.

Chorea and related movement disorders of paraneoplastic origin: the PNS EuroNetwork experience.

Chorea and other movement disorders are rarely described as paraneoplastic. The aim of this study was to describe 13 patients with paraneoplastic chorea and dystonia collected by the members of the paraneoplastic neurological syndrome (PNS) EuroNetwork and to review 29 cases from the literature. We analyzed neurological symptoms, severity of the neurological syndrome, delay in neurological diagnosis, associated cancer, oncological and neurological treatments received, and outcome. Eleven (1.2%) out of 913 patients with PNS were identified in the EuroNetwork register. Two more patients not included in the register were added. The overall population consisted of 13 patients with a median age of 75 years (range 49-82 years). In most patients, the movement disorder was classical choreoathetosis with symmetric involvement of the trunk, neck, and limbs. A minority of patients presented unilateral chorea, dystonia, and orobuccal dyskinesia. Associated symptoms, as polyneuropathy, encephalitis, psychiatric disturbances, or visual defects, were often present. The movement disorder usually had a subacute course. The most frequently associated cancer was small cell lung cancer (SCLC). Lymphoma, bowel, or kidney cancers were also reported. CV2/CRMP5 was the most frequently associated antibody, followed by Hu. Hyperintense lesions of the basal ganglia on T2-weighted images were seldom observed. Response to cancer therapy was observed in a minority of patients, but survival was short (17 months). As in other neurological diseases, movement disorders should also be suspected as paraneoplastic when they develop subacutely in older patients (usually over 50) and often in the presence of other ancillary neurological symptoms.

Anti-brain antibodies in adult patients with obsessive-compulsive disorder.

BACKGROUND: An autoimmune hypothesis has been suggested for a subtype of Obsessive-Compulsive Disorder (OCD) with childhood onset: obsessions, compulsions and/or tics would result from anti-streptococcal antibodies that cross-react with basal ganglia tissue based on molecular mimicry. Consistent with this hypothesis anti-brain antibodies were detected in sera of children with OCD and/or Tourette's syndrome. In the present study, we tested whether adults with OCD have anti-brain antibodies or other antibodies that serve as markers of autoimmunity. METHODS: Seventy-four DSM-IV OCD (YBOCS> or =16) subjects were recruited and compared to 44 controls with a current Major Depressive Episode for neurological symptoms, ALSO titres, anti-tissue and anti-thyroid antibodies. Anti-brain antibodies were tested by immunohistochemistry and Western blotting methods. RESULTS: The proportion of subjects with tic comorbidity or positive ASLO titre (>200 IU/ml) was significantly greater in OCD than in MDE patients (21.6 vs. 2.3% and 16.3 vs. 2.3%, respectively). No other differences in antibody parameters were found. 4/74 OCD patients (5.4%) and none of the controls resulted positive for anti-brain antibodies, with a band around 50-60 kDa at the Western blot analysis. LIMITATIONS: The methodology used to assess anti-brain antibodies. CONCLUSIONS: The majority of adult OCD patients do not seem to have autoimmunity disturbances as compared to a control group. However, a greater percentage of subjects with positive ASLO titres were found among OCD patients. For a small proportion of OCD patients, moreover, autoimmune reactions towards neuronal structures are present although further investigations are needed to demonstrate its etiopathogenetic relevance.