Outcomes and Health Care Service Use in Adults 50 Years or Older With and Without Multiple Sclerosis: A 6-Year Observational Analysis.

BACKGROUND: Multiple sclerosis (MS) typically presents in young adulthood. Recent data show the highest prevalence of MS in people aged 55 to 64 years; however, there are limited studies of this population. METHODS: Administrative US claims data from IBM-Truven MarketScan commercial and Medicare databases (2011-2017) were analyzed. People with MS 50 years or older were assigned to the aging MS cohort (n = 10,746). The matched controls were people 50 years or older without MS (n = 10,746). Multivariable models compared outcomes between groups. RESULTS: Infections were more frequent in the aging MS cohort vs matched controls (61% vs 45%; P < .0001); urinary tract, acute upper respiratory tract, and herpes zoster were the most frequent infection types. Malignancy rates were 20% for both groups (P = .8167); skin, breast, and prostate malignancies were the most frequent types. Skilled nursing facilities (aging MS cohort, 12%; matched controls, 3%; P < .0001) and MRI (aging MS cohort, 87%; matched controls, 37%; P < .0001) were used more frequently in the aging MS cohort; brain and spine were the most frequent types of MRI in the aging MS cohort. Time to first cane/walker or wheelchair use was shorter in the aging MS cohort (cane/walker use: HR, 2.1; 95% CI, 1.9-2.3; P < .0001; wheelchair use: HR, 6.9; 95% CI, 6.0-8.1; P < .0001). CONCLUSIONS: In people 50 years or older, measures typically associated with worse health primarily resulted from having MS rather than being a consequence of aging alone.

Conversion to eslicarbazepine acetate monotherapy: A pooled analysis of 2 phase III studies.

OBJECTIVE: To assess the efficacy and safety of eslicarbazepine acetate (ESL) monotherapy. METHODS: This post hoc pooled analysis of 2 randomized double-blind studies (093-045 and -046) included adults with partial-onset seizures medically uncontrolled by 1 or 2 antiepileptic drugs (AEDs). Following the baseline period (8 weeks), eligible patients were randomized 2:1 to receive ESL 1,600 mg or 1,200 mg once daily for 18 weeks; the primary endpoint was study exit by meeting predefined exit criteria (signifying worsening seizure control). In each study, treatment was considered effective if the upper 95% confidence limit for exit rate was lower than the historical control threshold (65.3%). RESULTS: Pooled exit rates were as follows: ESL 1,600 mg = 20.6% (95% confidence interval: 15.6%-26.8%); ESL 1,200 mg = 30.8% (23.0%-40.5%). Use of 2 baseline AEDs or rescue medication, US location, epilepsy duration ≥20 years, and higher maximum baseline seizure frequency were associated with higher exit risks. Median percent reductions in standardized seizure frequency between baseline and the 18-week double-blind period were as follows: ESL 1,600 mg = 43.2%; ESL 1,200 mg = 35.7%; baseline carbamazepine use was associated with smaller reductions. Safety profiles were similar between ESL doses. CONCLUSIONS: Exit rates for ESL monotherapy (1,600 mg and 1,200 mg once daily) were lower than the historical control threshold, irrespective of baseline AED use and region, with no additional safety concerns identified. Clinical factors and location clearly influence treatment responses in conversion-to-monotherapy trials. CLASSIFICATION OF EVIDENCE: This pooled analysis provides Class IV evidence that for adults with medically uncontrolled partial-onset seizures, ESL monotherapy is well tolerated and effective.

The histidine composition of the amyloid-ß domain, but not the E1 copper binding domain, modulates ß-secretase processing of amyloid-ß protein precursor in Alzheimer's disease.

Amyloid-ß protein precursor (AßPP) proteolysis by ß- and γ-secretases generates neurotoxic amyloid-ß (Aß)-peptides in Alzheimer's disease (AD). We have investigated the role of histidine residues within the extracellular E1 copper binding and Aß domains of AßPP in its proteolysis. By stably expressing histidine to alanine AßPP mutant constructs in SH-SY5Y cells, we show that mutations in the E1 copper binding domain had no impact on α- or ß-secretase processing. Mutation of histidine 14 within the Aß-domain specifically down-regulated ß-secretase processing without impacting on non-amyloidogenic proteolysis. Understanding how histidine 14 participates in AßPP proteolysis may reveal new intervention points for AD treatments.

The E1 copper binding domain of full-length amyloid precursor protein mitigates copper-induced growth inhibition in brain metastatic prostate cancer DU145 cells.

Copper plays an important role in the aetiology and growth of tumours and levels of the metal are increased in the serum and tumour tissue of patients affected by a range of cancers including prostate cancer (PCa). The molecular mechanisms that enable cancer cells to proliferate in the presence of elevated copper levels are, therefore, of key importance in our understanding of tumour growth progression. In the current study, we have examined the role played by the amyloid precursor protein (APP) in mitigating copper-induced growth inhibition of the PCa cell line, DU145. A range of APP molecular constructs were stably over-expressed in DU145 cells and their effects on cell proliferation in the presence of copper were monitored. Our results show that endogenous APP expression was induced by sub-toxic copper concentrations in DU145 cells and over-expression of the wild-type protein was able to mitigate copper-induced growth inhibition via a mechanism involving the cytosolic and E1 copper binding domains of the full-length protein. APP likely represents one of a range of copper binding proteins that PCa cells employ in order to ensure efficient proliferation despite elevated concentrations of the metal within the tumour microenvironment. Targeting the expression of such proteins may contribute to therapeutic strategies for the treatment of cancers.

The amyloid precursor protein represses expression of acetylcholinesterase in neuronal cell lines.

The toxic role of amyloid ß peptides in Alzheimer's disease is well documented. Their generation is via sequential ß- and γ-secretase cleavage of the membrane-bound amyloid precursor protein (APP). Other APP metabolites include the soluble ectodomains sAPPα and sAPPß and also the amyloid precursor protein intracellular domain (AICD). In this study, we examined whether APP is involved in the regulation of acetylcholinesterase (AChE), which is a key protein of the cholinergic system and has been shown to accelerate amyloid fibril formation and increase their toxicity. Overexpression of the neuronal specific isoform, APP695, in the neuronal cell lines SN56 and SH-SY5Y substantially decreased levels of AChE mRNA, protein, and catalytic activity. Although similar decreases in mRNA levels were observed of the proline-rich anchor of AChE, PRiMA, no changes were seen in mRNA levels of the related enzyme, butyryl-cholinesterase, nor of the high-affinity choline transporter. A γ-secretase inhibitor did not affect AChE transcript levels or enzyme activity in SN56 (APP695) or SH-SY5Y (APP695) cells, showing that regulation of AChE by APP does not require the generation of AICD or amyloid ß peptide. Treatment of wild-type SN56 cells with siRNA targeting APP resulted in a significant up-regulation in AChE mRNA levels. Mutagenesis studies suggest that the observed transcriptional repression of AChE is mediated by the E1 region of APP, specifically its copper-binding domain, but not the C-terminal YENTPY motif. In conclusion, AChE is regulated in two neuronal cell lines by APP in a manner independent of the generation of sAPPα, sAPPß, and AICD.

Zinc metalloproteinases and amyloid Beta-Peptide metabolism: the positive side of proteolysis in Alzheimer's disease.

Alzheimer's disease is a neurodegenerative condition characterized by an accumulation of toxic amyloid beta- (Aß-)peptides in the brain causing progressive neuronal death. Aß-peptides are produced by aspartyl proteinase-mediated cleavage of the larger amyloid precursor protein (APP). In contrast to this detrimental "amyloidogenic" form of proteolysis, a range of zinc metalloproteinases can process APP via an alternative "nonamyloidogenic" pathway in which the protein is cleaved within its Aß region thereby precluding the formation of intact Aß-peptides. In addition, other members of the zinc metalloproteinase family can degrade preformed Aß-peptides. As such, the zinc metalloproteinases, collectively, are key to downregulating Aß generation and enhancing its degradation. It is the role of zinc metalloproteinases in this "positive side of proteolysis in Alzheimer's disease" that is discussed in the current paper.