Butyrylcholinesterase K variant associated with higher enzyme activity in the temporal cortex of elderly patients.

There is evidence to suggest an involvement of the K variant of the butyrylcholinesterase gene (BCHE) in dementia. We have examined the relationship between BCHE genotype and butyrylcholinesterase (BuChE) activity in autopsy brain tissue. We studied 164 autopsy cases, 144 with dementia and 20 controls, including 13 K homozygotes and 48 K heterozygotes, from three centres: Newcastle, Oxford and London. Mean BuChE activity in temporal cortex was 37% higher in K homozygotes than in wild-type homozygotes. Linear regression analysis, controlling for gender, diagnosis, age at death and study centre, showed that the number of BCHE-K alleles was associated with increasing BuChE activity (p=0.009).

An extract of Salvia (sage) with anticholinesterase properties improves memory and attention in healthy older volunteers.

RATIONALE: Species of Salvia (sage) have a long-standing reputation in European medical herbalism, including for memory enhancement. In recent controlled trials, administration of sage extracts with established cholinergic properties improved cognitive function in young adults. OBJECTIVES: This randomised, placebo-controlled, double-blind, balanced, five-period crossover study investigated the acute effects on cognitive performance of a standardised extract of Salvia officinalis in older adults. MATERIALS AND METHODS: Twenty volunteers (>65 years of age, mean = 72.95) received four active doses of extract (167, 333, 666 and 1332 mg) and a placebo with a 7-day wash-out period between visits. Assessment involved completion of the Cognitive Drug Research computerised assessment battery. On study days, treatments were administered immediately following a baseline assessment with further assessment at 1, 2.5, 4 and 6 h post treatment. RESULTS: Compared with the placebo condition (which exhibited the characteristic performance decline over the day), the 333-mg dose was associated with significant enhancement of secondary memory performance at all testing times. The same measure benefited to a lesser extent from other doses. There also were significant improvements to accuracy of attention following the 333-mg dose. In vitro analysis confirmed cholinesterase inhibiting properties for the extract. CONCLUSIONS: The overall pattern of results is consistent with a dose-related benefit to processes involved in efficient stimulus processing and/or memory consolidation rather than retrieval or working memory efficiency. These findings extend those of the memory-enhancing effects of Salvia extracts in younger populations and warrant further investigation in larger series, in other populations and with different dosing regimes.

Butyrylcholinesterase: impact on symptoms and progression of cognitive impairment.

The most successful approach for treating people with Alzheimer's disease to date has been by improving cholinergic transmission using cholinesterase inhibitors. Many of these drugs selectively inhibit acetylcholinesterase but some agents inhibit both acetylcholinesterase and butyrylcholinesterase. Recent evidence from studies examining butyrylcholinesterase in post mortem brain samples from dementia patients and examining the relationship between butyrylcholinesterase polymorphisms and the progression of cognitive impairment in dementia with Lewy bodies and Alzheimer's disease add to a body of work suggesting that butyrylcholinesterase is present in key brain areas and may influence the maturation of plaques in Alzheimer's disease. These accumulating data suggest that butyrylcholinesterase contributes to disease progression in people with dementia, which may be particularly important in individuals with more severe dementia as butyrylcholinesterase activity increases with disease development. It is a priority for future clinical trials to determine whether agents which inhibit butyrylcholinesterase and acetylcholinesterase have a greater clinical efficacy.

Is gastric reflux a cause of otitis media with effusion in children?

OBJECTIVES/HYPOTHESIS: Otitis media with effusion is the most common cause of childhood deafness. Gastroesophageal reflux has been implicated in the disease pathogenesis; therefore, it is necessary to identify the presence or absence of gastric juice in the middle ear. STUDY DESIGN: Middle ear effusions were collected from children undergoing myringotomy. If gastric reflux has occurred, effusions should contain pepsin protein. METHODS: Total pepsin/pepsinogen protein, fibrinogen, and albumin content of effusions were measured in enzyme-linked immunosorbent assays using antibodies to porcine pepsin, human albumin, and human fibrinogen. Proteolytic activity of each effusion was measured at pH 2. The pH of effusions was measured. RESULTS: Fifty-nine of 65 effusion samples gave a positive result with the antipepsin antibody, which also recognized pepsinogen. Pepsin/pepsinogen levels ranged from 0.8 to 213.9 microg/mL (serum reference levels, 49.8-86.6 ng/mL). All effusions contained albumin and fibrinogen with respective ranges of 1.77 to 95.75 and 0.30 to 2.30 mg/mL (serum reference levels, 35-45 and 2.2 to 4.6 mg/mL, respectively). Acidic protease activity occurred in 19 of 65 effusion samples. The pH of effusion samples was 7 to 9. CONCLUSIONS: The majority of effusion samples contained pepsin/pepsinogen protein; only 29% were active. The pepsin level in effusion samples based on activity is substantially lower than levels based on antibody detection; however, the pH present would irreversibly inhibit pepsin, which would explain the low levels of active enzyme. Pepsin/pepsinogen levels in the effusion samples were up to 1000 times higher than serum levels, whereas albumin and fibrinogen levels were of the same magnitude. The pepsin in middle ear effusions is almost certainly due to reflux of gastric contents, and there may be a role for antireflux therapy in the treatment of otitis media with effusion.

Reflux of gastric juice and glue ear in children.

Otitis media with effusion (glue ear) is the most frequent cause of deafness in children. We investigated the role of gastric juice reflux in this disease. We measured pepsin concentrations in middle ear effusions from children using ELISA and enzyme activity assays. 45 (83%) of 54 effusions contained pepsin/pepsinogen at concentrations of up to 1000-fold greater than those in serum. Our data suggest that reflux of gastric juice could be a major cause of glue ear in children.