An observational study of cognitive function in patients with irritable bowel syndrome and inflammatory bowel disease.

BACKGROUND: Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are associated with several risk factors for developing cognitive impairment. These include altered cytokine levels, concurrent mood disorders, and the presence of chronic pain. This observational study aimed to explore the cognitive profile of patients with these conditions. METHODS: Participants completed the Cardiff Cognitive Battery, a series of computerized neuropsychological performance tests that examine a range of cognitive function including psychomotor speed, memory, and intelligence. A progressive analysis of covariance model was used with demographic details, anxiety and depression scores entered as covariates. Fecal calprotectin levels were measured in IBD patients to determine disease activity. KEY RESULTS: In total 231 participants were recruited (150 IBD patients, 40 IBS patients, and 41 healthy controls). IBD patients had significantly lower scores on fluid (p = 0.01) and crystalline intelligence tests (p = 0.028) compared to healthy volunteers, however, this reflected differences in concurrent mood disorder and level of education. When these factors were added as covariates, there was no significant difference between the groups. Duration and activity of disease did not affect cognitive function in IBD patients. Severity of symptoms had no impact on cognition in patients with IBS. CONCLUSIONS & INFERENCES: The results of this observational study do not support the hypothesis that IBS or IBD have an intrinsic disease process that is associated with cognitive dysfunction. It is possible that concurrent mood disorders, in particular depression, may affect the cognitive performance of patients with IBD in specific tasks.

Association of lactose sensitivity with inflammatory bowel disease--demonstrated by analysis of genetic polymorphism, breath gases and symptoms.

BACKGROUND: Sensitivity to lactose has been reported in Crohn's disease, but its true role in inflammatory bowel disease (IBD) is unclear. The genetic marker CC13910, on chromosome2, with measurement of breath hydrogen and methane, and gut and systemic symptoms, are now the most comprehensive tests for evaluating sensitivity to lactose. AIM: To investigate, for the first time, the prevalence of lactose sensitivity in IBD, using the most comprehensive tests for diagnosing this condition. METHODS: Prevalence of CC13910 genotype was investigated using RT-PCR in 165 patients (Crohn's disease = 70, ulcerative colitis = 95), and 30 healthy volunteers. Genotype was correlated with breath hydrogen and methane up to 6 h after 50 g of oral lactose, all symptoms being recorded for up to 48 h. Critically, Crohn's disease and ulcerative colitis patients were selected with no record of lactose sensitivity, in remission at the time of the test. RESULTS: Lactose sensitivity occurred in a much higher proportion of patients, (approximately 70%), with IBD than previously thought. Seventeen per cent had raised methane, without raised breath hydrogen; those with ulcerative colitis exhibiting most symptoms. All CC patients were lactose sensitive. There was no correlation between genetic phenotype and IBD. As substantial numbers of IBD patients were CT or TT, and were lactose sensitive, this polymorphism cannot explain full down-regulation of the lactase gene. CONCLUSIONS: Our results have implications for the clinical management of IBD. The high breath methane raised the possibility of a pathogenic role for methanogenic archaebacteria (Archaea) in IBD. This needs to be investigated.

Bacterial metabolic 'toxins': a new mechanism for lactose and food intolerance, and irritable bowel syndrome.

Lactose and food intolerance cause a wide range of gut and systemic symptoms, including gas, gut pain, diarrhoea or constipation, severe headaches, severe fatigue, loss of cognitive functions such as concentration, memory and reasoning, muscle and joint pain, heart palpitations, and a variety of allergies (Matthews and Campbell, 2000; Matthews et al., 2005; Waud et al., 2008). These can be explained by the production of toxic metabolites from gut bacteria, as a result of anaerobic digestion of carbohydrates and other foods, not absorbed in the small intestine. These metabolites include alcohols, diols such as butan 2,3 diol, ketones, acids, and aldehydes such as methylglyoxal (Campbell et al., 2005, 2009). These 'toxins' induce calcium signals in bacteria and affect their growth, thereby acting to modify the balance of microflora in the gut (Campbell et al., 2004, 2007a,b). These bacterial 'toxins' also affect signalling mechanisms in cells around the body, thereby explaining the wide range of symptoms in people with food intolerance. This new mechanism also explains the most common referral to gastroenterologists, irritable bowel syndrome (IBS), and the illness that afflicted Charles Darwin for 50 years (Campbell and Matthews, 2005a,b). We propose it will lead to a new understanding of the molecular mechanism of type 2 diabetes and some cancers.

Quantifying the 'hidden' lactose in drugs used for the treatment of gastrointestinal conditions.

BACKGROUND: Lactose intolerance affects 70% of the world population and may result in abdominal and systemic symptoms. Treatment focuses predominantly on the dietary restriction of food products containing lactose. Lactose is the most common form of excipient used in drug formulations and may be overlooked when advising these patients. AIM: To identify and quantify the amount of lactose in medications used for the treatment of gastrointestinal disorders and to identify 'lactose-free' preparations. METHODS: Medications used for the treatment of gastrointestinal disorders were identified from the British National Formulary (BNF). Their formulation including excipients was obtained from the Medicines Compendium. The lactose content and quantity in selected medications was measured using high-performance liquid chromatography (HPLC). RESULTS: A wide range of medications prescribed for the treatment of gastrointestinal conditions contain lactose. We have quantified the lactose content in a selection of medications using HPLC. Lactose is present in amounts that may contribute towards symptoms. Lactose-free alternatives were also identified. CONCLUSIONS: Lactose is present in a range of medications and may contribute towards symptoms. This may not be recognized by the prescribing doctor as excipients are not listed in the BNF, and the quantity of lactose is not listed on the label or in the accompanying manufacturer's leaflet.

Systemic lactose intolerance: a new perspective on an old problem.

Intolerance to certain foods can cause a range of gut and systemic symptoms. The possibility that these can be caused by lactose has been missed because of "hidden" lactose added to many foods and drinks inadequately labelled, confusing diagnosis based on dietary removal of dairy foods. Two polymorphisms, C/T13910 and G/A22018, linked to hypolactasia, correlate with breath hydrogen and symptoms after lactose. This, with a 48 hour record of gut and systemic symptoms and a six hour breath hydrogen test, provides a new approach to the clinical management of lactose intolerance. The key is the prolonged effect of dietary removal of lactose. Patients diagnosed as lactose intolerant must be advised of "risk" foods, inadequately labelled, including processed meats, bread, cake mixes, soft drinks, and lagers. This review highlights the wide range of systemic symptoms caused by lactose intolerance. This has important implications for the management of irritable bowel syndrome, and for doctors of many specialties.

Inflammatory response and body composition in chronic obstructive pulmonary disease.

Weight loss in chronic obstructive airways disease (COPD) is associated with an increased energy cost of breathing. To determine an association between body composition and the inflammatory response we studied 80 clinically stable patients. Body composition was determined anthropometrically and skeletal muscle mass was determined as the creatinine-height index (CHI). Forty patients had their nitrogen balance determined. Circulating concentrations of interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), and their soluble receptors were determined for 68 patients. Body mass index (BMI) was normal (> 20 kg/m(2)) in 55 patients, of whom 17 (31%) had a low CHI (< 80% predicted). A reduced CHI was associated with increased circulating levels of IL-6 (p = 0.001), TNF-alpha (p = 0.032) and their soluble receptors IL-6sr (p = 0.002), TNF-alpha sr1 (p = 0.03), and TNF-alpha sr2 (p = 0.001). Patients with a normal BMI and low CHI had inflammatory mediator levels similar to patients with a low BMI and CHI; both were significantly greater than in those with a normal BMI and CHI. Nitrogen balance was similar between normal and low CHI groups, although nitrogen excretion was significantly increased in the low CHI group. Skeletal muscle loss in COPD is probably multifactorial in origin, but our data suggest a link with systemic inflammation, even when weight loss is inapparent.

Engineering the C-terminus of firefly luciferase as an indicator of covalent modification of proteins.

Protein kinase recognition sequences and proteinase sites were engineered into the cDNA encoding firefly luciferase from Photinus pyralis in order to establish whether these modified proteins could be developed as bioluminescent indicators of covalent modification of proteins. Two key domains of the luciferase were modified in order to identify regions of the protein in which peptide sequences may be engineered whilst retaining bioluminescent activity; one between amino acids 209 and 227 and the other at the C-terminus, between amino acids 537 and 550. Mutation of amino acids between residues 209 and 227 reduced bioluminescent activity to less than 1% of wild-type recombinant. In contrast engineering peptide sequences at the C-terminus resulted in specific activities ranging from 0.06-120% of the wild-type recombinant. Addition of cyclic AMP dependent protein kinase catalytic subunit, to a variant luciferase incorporating the kinase recognition sequence, LRRASLG, with a serine at amino-acid position 543 resulted in a 30% reduction in activity. Alkaline phosphatase treatment restored activity. The bioluminescent activity of a variant luciferase containing a thrombin recognition sequence, LVPRES, with the cleavage site positioned between amino acid 542 and 543, decreased by 50% when incubated in the presence of thrombin. The results indicate regions within luciferase where peptide sequences may be engineered while retaining bioluminescent activity and have shown changes in bioluminescent activity when these sites are subjected to covalent modification. Changes in secondary structure, charge and length at the C-terminus of luciferase disrupt the microenvironment of the active site, leading to alterations in light emission. This has important implications both in understanding the evolution of beetle bioluminescence and also in development of bioluminescent indicators of the covalent modification of proteins.

Cholesterol rich apo B containing lipoproteins and smoking are independently associated with macrovascular disease in normotensive NIDDM patients.

A cross-sectional study of macrovascular disease (MVD) and associated metabolic and other risk factors was conducted in 87 normotensive NIDDM patients. MVD was assessed by Rose questionnaire, 12 lead resting ECG, duplex scanning of carotid and peripheral vessels, and ankle:brachial systolic blood pressure ratio. Fasting serum total cholesterol, total triglycerides, LDL cholesterol, HDL cholesterol, apolipoproteins AI and B, lipoprotein (a), HbA1, plasma glucose, insulin, and C-peptide responses to a carbohydrate rich meal, body mass index (BMI), waist-hip ratio, urinary albumin excretion rate, blood pressure, smoking and family history were assessed as possible 'risk factors'. Apolipoprotein:lipid ratios were calculated to estimate lipoprotein composition. Thirty-six patients had demonstrable MVD. The presence of MVD was associated with higher total triglycerides (p < 0.05), BMI (p < 0.05), systolic blood pressure (p < 0.01), a lower apo B:non HDL cholesterol ratio (p < 0.001), and smoking (p < 0.005) but no other measures. Multiple regression analysis revealed smoking and a low apo B:non HDL cholesterol to be independently associated with MVD. The low apo B:non HDL cholesterol suggests a high cholesterol content of apo B containing lipoproteins. This lipoprotein abnormality is not a feature of NIDDM, but when present in these patients may be particularly atherogenic.

Apolipoprotein and lipid ratios in treated non-insulin dependent diabetics.

Fasting total cholesterol (TC), triglycerides (TG), HDL cholesterol (HDL C), apolipoprotein A1 (apo A1) and apolipoprotein B (apo B) were measured in 35 non-insulin dependent diabetic patients treated by diet with or without sulphonylureas and 35 control subjects matched for age, sex, and body mass index. Ratios of apolipoprotein and lipid were calculated. The diabetics were well controlled with a mean (+/- SD) glycosylated haemoglobin (HbA1) of 8.5 +/- 1.3% (normal range less than 8%). Compared to non-diabetic control subjects apo A1: HDL C, apo B: TC, and apo B: calculated LDL C were significantly higher in the NIDDM patients, (112.9 +/- 26.3 vs 83.0 +/- 28.7, p less than 0.001, 15.89 +/- 1.68 vs 14.22 +/- 3.48, p less than 0.01, and 24.32 +/- 3.19 vs 22.33 +/- 5.49, p less than 0.05 respectively). These findings reflect differences in cholesterol content in the absence of differences in apolipoprotein concentrations between the NIDDM and control groups. The cardiovascular risk ratio HDL C: non HDL C was significantly lower in the NIDDM patients (0.25 +/- 0.09 vs 0.31 +/- 0.15, p less than 0.01), but there was no difference in apo A1:apo B (1.42 +/- 0.42 vs 1.43 +/- 0.52, NS). Although apo A1: apo B correlated well with HDL C:non HDL C in both NIDDM and controls (r = 0.88, 0.72, p less than 0.001 respectively) the slope of the relationships differed b = 4.01 NIDDM vs 2.50 controls (95% confidence intervals for difference is 0.22-2.78). Simple widely available methods can identify abnormalities of lipoprotein content in treated NIDDM patients. Both HDL and LDL contain less cholesterol.(ABSTRACT TRUNCATED AT 250 WORDS)

The adrenochrome pathway: the major route for adrenalin catabolism by polymorphonuclear leucocytes.

Oxygen radical production by polymorphonuclear leucocytes stimulated the oxidation of adrenalin through the adrenochrome pathway. This was detected either spectrophotometrically at 480 nm or separated by hplc and detected radiochemically. The oxidation was detectable within 5 min and continued for at least 4 h. Over the adrenalin concentration range 0.3 microM to 10 mM more than 80% of the oxidation that occurred was through the adrenochrome pathway, the remainder being through the amine oxidase, catechol methyl transferase pathway. Medium isolated after stimulation of the polymorphonuclear leucocytes was also able to oxidise adrenalin to adrenochrome. The results provide a cellular mechanism for the formation of adrenochrome and the other metabolites on this pathway of adrenalin metabolism, in inflammatory conditions where polymorphonuclear leucocyte infiltration occurs.

The adrenochrome pathway. A potential catabolic route for adrenaline metabolism in inflammatory disease.

Polymorphonuclear leukocytes activated by latex (polystyrene) beads or the chemotactic peptide N-formyl Met Leu Phe stimulated the oxidation of adrenaline (0.3 microM-10 mM) to adrenochrome, detected spectrophotometrically at 480 nm or by a high-performance liquid chromatographic (HPLC) method. This oxidation was detectable within 5 min and continued for at least 4 hr. Over the concentration range 0.3-10 microM, more than 80% of the adrenaline oxidation occurred via the adrenochrome pathway rather than the amine oxidase-catechol methyltransferase pathway. Medium isolated after stimulation of the polymorphonuclear leukocytes retained the ability to oxidize adrenaline to adrenochrome. Serum from patients after myocardial infarction induced more oxidation of adrenaline to adrenochrome than control serum. Superoxide dismutase, catalase, and azide inhibited by 70-95% the oxidation of adrenaline to adrenochrome, either by cells or medium. Commercially available adrenochrome was biologically active, but some of the actions were due to contaminants of the preparation. HPLC of an extract of synovial fluid from a patient with rheumatoid arthritis, a fluid that contains polymorphonuclear leukocytes, showed a peak identical to that of the adrenochrome standard. The results provide a cellular mechanism for adrenochrome formation and preliminary evidence that adrenochrome can be produced in inflammatory conditions in which polymorphonuclear leukocyte infiltration occurs.