Early cognitive decline after bilateral subthalamic deep brain stimulation in Parkinson's disease patients with GBA mutations.

BACKGROUND: Subthalamic nucleus deep brain stimulation (STN-DBS) has demonstrated its efficacy on motor complications in advanced Parkinson's disease (PD) but does not modify disease progression. Genetic forms of PD have been associated with different cognitive progression profiles. OBJECTIVE: To assess the effect of PD-related genetic mutations on cognitive outcome after STN-DBS. METHODS: Patients with STN-DBS were screened for LRRK2, GBA, and PRKN mutations at the Pitié-Salpêtrière Hospital between 1997 and 2009. Patients with known monogenetic forms of PD from six other centers were also included. The Mattis Dementia Rating Scale (MDRS) was used to evaluate cognition at baseline and one-year post-surgery. The standardized Unified PD Rating Scale (UPDRS) evaluation On and Off medication/DBS was also administered. A generalized linear model adjusted for sex, ethnicity, age at onset, and disease duration was used to evaluate the effect of genetic factors on MDRS changes. RESULTS: We analyzed 208 patients (131 males, 77 females, 54.3 ± 8.8 years) including 25 GBA, 18 LRRK2, 22 PRKN, and 143 PD patients without mutations. PRKN patients were younger and had a longer disease duration at baseline. A GBA mutation was the only significant genetic factor associated with MDRS change (ß = -2.51, p = 0.009). GBA mutation carriers had a more pronounced post-operative MDRS decline (3.2 ± 5.1) than patients with LRRK2 (0.9 ± 4.8), PRKN (0.5 ± 2.7) or controls (1.4 ± 4.4). The motor response to DBS was similar between groups. CONCLUSION: GBA mutations are associated with early cognitive decline following STN-DBS. Neuropsychological assessment and discussions on the benefit/risk ratio of DBS are particularly important for this population.

SUMOylation by SUMO2 is implicated in the degradation of misfolded ataxin-7 via RNF4 in SCA7 models.

Perturbation of protein homeostasis and aggregation of misfolded proteins is a major cause of many human diseases. A hallmark of the neurodegenerative disease spinocerebellar ataxia type 7 (SCA7) is the intranuclear accumulation of mutant, misfolded ataxin-7 (polyQ-ATXN7). Here, we show that endogenous ATXN7 is modified by SUMO proteins, thus also suggesting a physiological role for this modification under conditions of proteotoxic stress caused by the accumulation of polyQ-ATXN7. Co-immunoprecipitation experiments, immunofluorescence microscopy and proximity ligation assays confirmed the colocalization and interaction of polyQ-ATXN7 with SUMO2 in cells. Moreover, upon inhibition of the proteasome, both endogenous SUMO2/3 and the RNF4 ubiquitin ligase surround large polyQ-ATXN7 intranuclear inclusions. Overexpression of RNF4 and/or SUMO2 significantly decreased levels of polyQ-ATXN7 and, upon proteasomal inhibition, led to a marked increase in the polyubiquitination of polyQ-ATXN7. This provides a mechanism for the clearance of polyQ-ATXN7 from affected cells that involves the recruitment of RNF4 by SUMO2/3-modified polyQ-ATXN7, thus leading to its ubiquitination and proteasomal degradation. In a SCA7 knock-in mouse model, we similarly observed colocalization of SUMO2/3 with polyQ-ATXN7 inclusions in the cerebellum and retina. Furthermore, we detected accumulation of SUMO2/3 high-molecular-mass species in the cerebellum of SCA7 knock-in mice, compared with their wild-type littermates, and changes in SUMO-related transcripts. Immunohistochemical analysis showed the accumulation of SUMO proteins and RNF4 in the cerebellum of SCA7 patients. Taken together, our results show that the SUMO pathway contributes to the clearance of aggregated ATXN7 and suggest that its deregulation might be associated with SCA7 disease progression.

Transcriptome Analysis of Peripheral Blood in Chronic Inflammatory Demyelinating Polyradiculoneuropathy Patients Identifies TNFR1 and TLR Pathways in the IVIg Response.

We have studied the response to intravenous immunoglobulins (IVIg) by a transcriptomic approach in 11 chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) patients (CIDP duration = 6 [0.83-6.5] years). RNA was extracted from cells in whole blood collected before and 3 weeks after IVIg treatment, and hybridized on Illumina chips. After RNA quality controls, gene expression was analyzed using statistical tests fitted for microarrays (R software, limma package), and a pathway analysis was performed using DAVID software. We identified 52 genes with expression that varied significantly after IVIg (fold change [FC] > 1.2, P < 0.001, false discovery rate [FDR] <0.05). Among these 52 genes, 7 were related to immunity, 3 were related to the tumor necrosis factor (TNF)-α receptor 1 (TNFR1) pathway (inhibitor of caspase-activated DNase (ICAD): FC = 1.8, P = 1.7E-7, FDR = 0.004; p21 protein-activated kinase 2 [PAK2]: FC = 1.66, P = 2.6E-5, FDR = 0.03; TNF-α-induced protein 8-like protein 1 [TNFAIP8L1]: P = 1.00E-05, FDR = 0.026), and 2 were related to Toll-like receptors (TLRs), especially TLRs 7 and 9, and were implicated in autoimmunity. These genes were UNC93B1 (FC = 1.6, P = 2E-5, FDR = 0.03), which transports TLRs 7 and 9 to the endolysosomes, and RNF216 (FC = 1.5, P = 1E-05, FDR = 0.03), which promotes TLR 9 degradation. Pathway analysis showed that the TNFR1 pathway was significantly lessened by IVIg (enrichment score = 24, Fischer exact test = 0.003). TNF-α gene expression was higher in responder patients than in nonresponders; however, it decreased after IVIg in responders (P = 0.04), but remained stable in nonresponders. Our data suggest the actions of IVIg on the TNFR1 pathway and an original mechanism involving innate immunity through TLRs in CIDP pathophysiology and the response to IVIg. We conclude that responder patients have stronger inflammatory activity that is lessened by IVIg.

Contraceptive steroids from pharmaceutical waste perturbate junctional communication in Sertoli cells.

The potential health impact of pharmaceutical waste is now a growing concern. Contraceptive steroids are prominent environmental contaminants and thus may act as endocrine disruptors. Numerous xenobiotics hamper Sertoli cells junctional communication which is known to participate in spermatogenesis control. This has been associated with male subfertility and testicular cancer. We investigated three contraceptive molecules found in the environment for their potential impact on Sertoli cells gap junction functionality: 17a-ethynylestradiol, medroxyprogesterone acetate and levonorgestrel. Four other non-steroid drugs also found in the environment were included in the study. Communication disruption was analyzed in vitro in murine seminiferous tubules and the 42GPA9 Sertoli cell line. Steroids modulated connexin43 trafficking and impaired junctional communication through rapid effects apparently acting on the cell membrane but not on Cx43 expression. The 4 non-steroid compounds showed no effect. Longer exposure to steroids increased gap junction impairment, which was associated in part with Na/K ATPase internalization. Estrogen receptors (ER) did not appear to be involved in gap junction disruption: Sertoli cells are devoid of ERalpha and only express the cytoplasmic beta isoform. ERbeta localization was not modified by either steroid. The threshold level was surprisingly low, around 10(-16) M. We conclude that steroidal pollutants disrupt Sertoli cells junctional communication in vitro at concentrations that can be found in the environment.

[Cell therapy in cartilage repair: cellular and molecular bases]. / La thérapie cellulaire du cartilage : bases cellulaires et moléculaires.

The destruction of articular cartilage represents the outcome of most inflammatory and degenerative rheumatic diseases and leads to severe disability. Articular cartilage being unable to repair spontaneously, alterations of the joint surface often results in end-stage osteoarthritis, requiring surgical intervention and total joint replacement. This makes damaged tissues repair a major challenge in our aging society. Cartilage harbors only one cell type, the chondrocyte, which synthesizes and secretes specific matrix proteins such as type II collagen and high molecular weight proteoglycans. Matrix proteins are responsible for the conservation of the chondrocyte phenotype and the maintenance of the mechanical functions of cartilage. Development of therapeutic strategies for cartilage repair should thus comprise not only the replacement of lost cartilage cells but also that of extracellular matrix with cartilage-like properties. Different protocols are under investigation. The most commonly employed materials include transplantation of autologous osteochondral tissue. More recently, cell-based therapies using autologous mature chondrocytes or pre-chondrogenic stem cells have drawn particular attention. Tissue-engineering procedures represent the actual trend in cartilage repair. This approach combines biodegradable polymeric three-dimensional matrixes and isolated prechondrogenic stem cells. The cells are seeded within the biocompatible matrix and then implanted into the joint. Numerous non-degradable and degradable polymers, which efficiently "mimic" the natural surroundings of cartilage cells, are currently under investigation.

Oestrogens inhibit interleukin 1beta-mediated nitric oxide synthase expression in articular chondrocytes through nuclear factor-kappa B impairment.

OBJECTIVES: To investigate the presence and functionality of oestrogen receptor alpha (ERalpha) in interleukin (IL)1beta-treated rabbit articular chondrocytes in culture, and to determine the mechanisms of 17beta oestradiol (E2) effects on IL1beta-induced inducible nitric oxide synthase (iNOS) expression. METHODS: The presence and functionality of ERalpha were investigated by immunocytochemistry and transient expression of an E2-responsive reporter construct. iNOS expression and production were determined by transient expression of a chimeric iNOS promoter-luciferase construct and protein immunoblotting. Nitric oxide (NO) production was determined by the Griess reaction. DNA-binding activities of nuclear factor-kappaB (NF-kappaB) and activated protein 1 were determined by electrophoretic mobility shift assay (EMSA)-ELISA assays. Nuclear translocation of p65 was studied by immunocytochemistry. RESULTS: ERalpha was identified in the nucleus of chondrocytes. ERalpha efficiently transactivated a transiently expressed E2-responsive construct. On IL1beta treatment, ERalpha partially diffused from its nuclear localisation into the cytoplasm and its transactivation ability was impaired. Nevertheless, E2, tamoxifen and raloxifene efficiently inhibited IL1beta-induced NO production (-34%, -31% and -36%, respectively). E2 decreased IL1beta-induced iNOS protein expression (-40%). Transient expression of an iNOS promoter construct strongly suggested that iNOS expression was inhibited at the transcriptional level, and EMSA-ELISA assays showed that E2 reduced (-60%) the IL1beta-induced p65 DNA-binding capacity. Finally, the p65 nuclear translocation induced by IL1beta was also strongly decreased by E2. CONCLUSIONS: Our data support a reciprocal antagonism between oestrogens and IL1beta, ultimately resulting in the decrease of cytokine-dependent NO production through transcriptional inhibition of iNOS expression. This effect was associated with selective inhibition of p65 DNA binding and nuclear translocation.