Low trehalase activity is associated with abdominal symptoms caused by edible mushrooms

BACKGROUND

The purpose of the study was to evaluate whether maldigestion of trehalose causes abdominal symptoms and which available diagnostic method best distinguishes intolerant from tolerant subjects.

METHODS

A 25-g oral trehalose load test was performed in 64 subjects. The 19 experiencing clear symptoms constituted the trehalose-intolerant subjects. Changes from base-line levels of blood glucose, breath hydrogen, and methane and symptoms were recorded after the test. Trehalase activity was determined in serum and on a duodenal biopsy specimen obtained by endoscopy.

RESULTS

Intolerant subjects were best differentiated from tolerant subjects by changes in breath gases (hydrogen and methane) and duodenal trehalase to sucrase ratio. The change in breath gases correlated inversely with duodenal trehalase activity, duodenal trehalase to sucrase ratio, and plasma trehalase activity. The correlation between serum and duodenal trehalase activities was on the order of 0.6. Two subjects were found to have trehalase deficiency.

CONCLUSIONS

It is obvious that trehalose maldigestion can cause symptoms similar to those of lactose maldigestion and intolerance. Three factors control the genesis of symptoms: 1) the activity of small-bowel trehalase: if it is low, trehalose is maldigested and more trehalose is passed into the colon; 2) the maldigested trehalose, which causes osmotic water flow into the colon, resulting in loose stools and diarrhea; and 3) most importantly, the microflora of the colon, from which symptoms will arise if there are bacteria capable of producing gases from maldigested trehalose. If colonic bacteria cannot produce gases, then distention of the abdomen and intestinal gas expulsion as eructations and flatus will not occur.

Association between M/L55-polymorphism of paraoxonase enzyme and oxidative DNA damage in patients with type 2 diabetes mellitus and in control subjects

The paraoxonase enzyme (PON) gene polymorphism causes a change of methionine (M-allele) to leucine (L-allele). PON may reduce low density lipoprotein oxidation and prevent atherosclerosis. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a sensitive index of oxidative DNA damage. We have studied the association between the PON genotypes and the urinary excretion of 8-OHdG. The study population consisted of 93 Finnish type 2 diabetes patients and 106 non-diabetic control subjects. The 24-h excretion of 8-OHdG was significantly higher in diabetic patients than in control subjects (P < 0.001). In control subjects, the ratio of the 8-OHdG/glomerular filtration rate increased in order of genotype from MM to ML to LL (P < 0.0412). These results suggest that lipid peroxidation may have an effect on DNA oxidation.

Autoantibodies against oxidized low density lipoprotein in patients with angiographically verified coronary artery disease

Oxidation of low density lipoproteins (LDL) obviously plays an important role in the pathogenesis of atherosclerosis. The purpose of the study was to determine whether antibodies against oxidized LDL are associated with coronary artery disease (CAD). We determined the serum levels of antibodies against copper-oxidized LDL by enzyme-linked immunosorbent assay in 58 patients with angiographically verified CAD and 34 controls without CAD. The mean antibody level, expressed in optical density units, was significantly higher in patients than in controls (0.150+/-0.088 versus 0.094+/-0.054, respectively; P=0.00089). In logistic regression analysis, high antibody level against oxidized LDL was associated significantly with CAD (P=0.0114), independent of age (P=0.00137), gender (P=0.0021), body mass index (P=0.5947), triglyceride concentration (P=0.9813), and total cholesterol-high density lipoprotein (HDL) cholesterol (P=0.0080) group. Similar analysis in nondiabetic subjects (n=79) and in men only (n=75) showed analogous results, with only minor changes in P values. The antibody level against oxidized LDL differed significantly between nonsmokers and smokers in CAD patients (P<0.00197) but not in controls (P=NS). In addition, the antibody level against oxidized LDL differed significantly between nonsmokers and smokers in subjects with low HDL cholesterol (</=0.9 mmol/L) but not in subjects with high HDL cholesterol (>0.9 mmol/L). In conclusion, elevated levels of antibodies against oxidized LDL were associated with CAD. The data suggest that oxidized LDL plays a role in the pathogenesis of atherosclerosis and suggest a protective function for HDL against LDL oxidation.

Mutation C677T of methylenetetrahydrofolate reductase gene is not associated with coronary artery disease, but possibly with albuminuria, in type 2 diabetic patients

The missense mutation in the 677th nucleotide (C677T) of methylenetetrahydrofolate reductase gene causes substitution of valine (V) for alanine (A) resulting in three genotypes VV, VA and AA. The VV genotype causes hyperhomocysteinemia and may be a risk factor for coronary artery disease. We determined genotypes by polymerase chain reaction and subsequent restriction fragment length analysis and compared them in 84 patients with type 2 diabetes and in 115 non-diabetic subjects with and without coronary disease. Fractional urinary excretion rate of albumin was assessed by nephelometry. The VV, VA, and AA frequencies in the diabetic and in the control groups were 0.095, 0.357, 0.548 and 0.061, 0.417, 0.522, respectively (p = NS, diabetic vs. controls, chi2 test). Genotype frequencies did not differ in either diabetic or control subjects between those with or those without coronary disease (chi2 test). The fractional urinary excretion rate of albumin (mean +/-SD) in diabetic patients with the VV genotype i.e. 1.59 +/-0.71 was lower (Kruskall-Wallis test p = 0.002) than in the other genotypes i.e. VA 5.98 +/-9.75 and AA 3.75 +/-4.77, respectively (post-hoc Mann-Whitney test VV vs. VA p = 0.005 and VV vs. AA p = 0.054, respectively). We found that in patients with type 2 diabetes the methylenetetrahydrofolate reductase VV genotype was associated with a low urinary albumin excretion but not with coronary artery disease or diabetes per se.

Apolipoprotein A-IV polymorphism in Saami and Finns: frequency and effect on serum lipid levels

Apolipoprotein A-IV (apoA-IV) is a glycoprotein constituent of triglyceride-rich and high-density lipoproteins (HDL) and may thus play an important role in lipid metabolism. In Finland two common isoforms (A-IV-1 and A-IV-2) of apoA-IV have been found. The isoforms are the result of the G to T substitution in the third base of the codon 360 in the apoA-IV-2 allele of the apoA-IV gene. The purpose of the study was to determine the apoA-IV allele frequencies in the Saami and the Finns, and to relate the apoA-IV phenotypes to serum lipids. The sample was drawn in connection with a Reindeer Herders' Health Survey performed in northern Finland in 1989. The study group included 248 men with known ethnic origin, Saami and Finns, who lived in the area of the nine northernmost municipalities of Finland. ApoA-IV phenotypes from 71 Saami (both parents Saami) and 177 Finns (both parents Finns) were determined by isoelectric focusing and Western blotting. Serum lipids were determined enzymatically. ApoA-IV allele frequencies in the Saami and the Finns were for A-IV-1 0.894 vs 0.944 and for A-IV-2 0.106 vs 0.056, respectively (chi2-test, P < 0.05). The effect of the apoA-IV phenotype on serum HDL-cholesterol levels differed significantly between the Saami and the Finns (two-way ANCOVA, interaction between ethnicity and apoA-IV phenotype, P < 0.02). In the Saami, HDL-cholesterol levels were significantly higher in the apoA-IV-2/1 than in the apoA-IV-1/1 phenotypes (ANCOVA, P < 0.05). Mean total cholesterol, low-density lipoprotein (LDL)-cholesterol, apolipoprotein B, HDL-cholesterol and triglyceride levels did not differ statistically significantly between the Saami and the Finns. Yet, there was a trend in the Saami of having higher mean total cholesterol, LDL-cholesterol and apolipoprotein B levels than the Finns among the apoA-IV-2/1 phenotypes, while there was only a small difference in these parameters between the Saami and the Finns among the apoA-IV-1/1 phenotypes. In conclusion, the Saami have a higher frequency of the apoA-IV-2 allele than the Finns and most of the other studied populations.

The effect of short-term fasting, apolipoprotein E gene polymorphism, and sex on plasma lipids

The effect of 1 wk of supervised fasting on plasma lipid concentrations in subjects with different apolipoprotein E (apo E) phenotypes was studied in 58 healthy free-living volunteers. The participants consumed an 870-kJ(208 kcal)/d liquid diet containing fruit and berry juices, tea, and water. The decline in plasma total cholesterol during 1 wk of fasting was 0.46 mmol/L in women and 0.35 mmol/L in men. The decreases were significant in both women and men. The response patterns of plasma total cholesterol were not significantly different between the sexes. In men, the changes in plasma low-density-lipoprotein cholesterol during the fast differed significantly (P = 0.0181) between the apo E phenotypes, whereas in women there were no differences due to phenotype (P = 0.695). The magnitude of the change in plasma triacylglycerol during the fast was different between the sexes (P = 0.0099). The changes in plasma triacylglycerols differed significantly between apo E phenotype groups in men (P = 0.0295) but not in women (P = 0.0661). Statistical comparison between different apo E phenotypes was performed with and without the small apo E3,2+E2,2 group, with essentially similar results. During fasting, plasma high-density-lipoprotein cholesterol concentrations decreased slightly but not significantly. The study shows significant differences in the associations of apo E alleles and sex on plasma lipid responses during fasting and illustrates the importance of gene-diet interactions in the regulation of lipid metabolism in humans.

Impaired ovarian function and risk factors for atherosclerosis in premenopausal women

OBJECTIVES

The aim of the study was to obtain information on the possible relationship between impaired ovarian function and risk factors for cardiovascular disease.

MATERIAL AND METHODS

Serum lipid levels, plasma fibrinolytic potential and histological and biochemical changes in the intima of the uterine artery were investigated in premenopausal women with irregular menstrual cycles, and the results were compared with those from regularly menstruating women. In addition, the same parameters were studied in postmenopausal women on hormone replacement therapy (HRT) and in postmenopausal women who had never used HRT. In total 64 patients undergoing hysterectomy for benign reasons were included the study.

RESULTS

Plasma fibrinogen concentration was significantly higher in irregularly menstruating women as compared with women with regular cycles. In women with irregular cycles thickened or sclerotic arterial intima was a significantly more common finding as compared with regularly menstruating women. A significant positive correlation was observed between plasma fibrinogen concentration and intimal esterified cholesterol content in women with thickened or sclerotic uterine artery.

CONCLUSIONS

These data suggest an important role for normal ovarian function in the prevention of atherosclerosis.

Women have a larger and less atherogenic low density lipoprotein particle size than men

Some epidemiological studies have shown that serum total cholesterol increases with age. especially in women. On the other hand, the risk of coronary artery disease is smaller in women than in men. Earlier studies have shown that a small dense low density lipoprotein (LDL) is more atherogenic than a large LDL. We studied LDL size and apolipoprotein E (apo E) phenotypes in premenopausal and postmenopausal women and in men at the same age. In this study 342 subjects participating in a health screening study were examined. There were four subgroups: 40-year-old men (n = 85), 40-year-old women (n = 80), 70-year old men (n = 88) and 70-year-old women (n = 89). In the present study LDL size was larger (P < 0.01) in women (26.39 +/- 0.07 nm) than in men (25.95 +/- 0.07 nm). We found that LDL size correlated highly positively (r = 0.606; P < 0.001) with serum high density lipoprotein (HDL) concentration and inversely with serum triglyceride concentration (r = -0.627; P < 0.001). Measuring serum HDL cholesterol and triglycerides in health screening studies gives information indirectly about LDL size and its atherogenicity. Apo E phenotype was not significantly associated with serum triglycerides, but was associated with LDL size, LDL cholesterol, total cholesterol and HDL cholesterol. In our sample LDL size decreased and LDL cholesterol and total cholesterol increased according to the most prevalent apo E phenotypes in the order E2/3, E3/3, E3/4 and E4/4. Subjects with phenotype apo E4/4 had the smallest LDL size (25.70 +/- 0.19 nm), the highest total cholesterol (6.53 +/- 0.35 mmol/l) and the lowest HDL cholesterol values (1.28 +/- 0.04 mmol/l). We conclude that there was a significant interaction between sex and age in serum total cholesterol which was highest in older women. However, their LDL size was larger and their LDL is less atherogenic. Apo E phenotype had a significant influence on LDL size.

Apolipoprotein E polymorphism, serum lipids, myocardial infarction and severity of angiographically verified coronary artery disease in men and women

In several populations, the apolipoprotein E (apo E) allele epsilon 4 is associated with high concentration of plasma total and low density lipoprotein (LDL)-cholesterol and coronary artery disease (CAD). We determined the apo E phenotypes of 309 patients with angiographically verified CAD and 38 patients without CAD by isoelectric focusing and Western blotting. In men with CAD, the plasma total and LDL-cholesterol increased according to apo E phenotype in the following order: E3/2 < E3/3 < E4/3 < E4/4 (P = 0.03 for total cholesterol, P = 0.007 for LDL-cholesterol). In women, there was a similar trend (P = 0.22 for total cholesterol, P = 0.15 for LDL-cholesterol). The relative frequency of men with three vessel CAD increased (P = 0.43) together with LDL-cholesterol levels (P = 0.05) according to apo E phenotype E3/2, E3/3, E4/3, E4/4. Total and LDL-cholesterol levels were higher in patients with three vessel CAD than in patients with less serious types of CAD (P = 0.02 for total cholesterol, P = 0.007 for LDL-cholesterol). The relative frequency of patients with myocardial infarction increased according to apo E phenotype (P = 0.51). Both in men and women, there were no differences between apo E phenotypes in age at occurrence of the first myocardial infarction. The apo E allele frequencies of patients with CAD vs. without CAD were 2.3% vs. 1.3% for epsilon 2, 79.0% vs. 76.3% for epsilon 3 and 18.7% vs. 22.4% for epsilon 4. There were no statistically significant differences in apo E allele or phenotype frequencies between patients with CAD and without CAD or between patients with CAD and the general Finnish population. Our results support previous studies in suggesting that the apo E allele epsilon 4 is a risk factor for atherosclerosis, which affects plasma total and LDL-cholesterol. In addition, our results suggest that the apo E allele determines the severity of CAD.

Hormone replacement therapy and atherosclerosis

Atherosclerotic changes associated with long-term hormone replacement therapy (HRT) were evaluated in 20 postmenopausal women (mean age, 62.8 +/- 6.1 years). The duration of hormone therapy was 10.1 +/- 3.4 (SD) years. For 9 women the HRT was sequential estradiol valerate plus levonorgestrel, for 6 women estradiol valerate plus medroxyprogesterone acetate and for 5 women estradiol valerate alone. Examinations consisted of histologic and biochemical studies of the uterine artery and ultrasonographic examinations of carotid arteries, aorta and iliac arteries. The findings were compared with those in 20 postmenopausal women of similar age and with similar body mass indexes who had never received HRT. Additionally, the same examinations were performed on 10 premenopausal women (48.3 +/- 4.6 years). The uterine artery was histologically normal in all the premenopausal women studied. Among the postmenopausal women without HRT, a histologically normal uterine artery was found in 5% and in women on HRT in 55% of cases (P < .01). In medicolegal autopsies, atherosclerosis in the uterine artery correlated significantly with atherosclerosis in the coronary artery and aorta. The free cholesterol content of the intima media in premenopausal women was lower than in postmenopausal women without HRT. The percentage of linoleic acid in the intima was significantly lower and that of docosapentaenoic acid significantly higher in premenopausal women and in postmenopausal women on HRT than in postmenopausal women without HRT. In the ultrasonographic examination atherosclerosis in the carotid artery was less common in premenopausal women and in women on HRT than in postmenopausal women without HRT. In this material, histologic, biochemical and radiologic studies showed that HRT may be protective against atherosclerosis.

Relationship of alcohol consumption to changes in HDL-subfractions

Epidemiological studies have consistently shown an apparent protective effect of moderate alcohol consumption on coronary artery disease (CAD). This has been considered to be due to the rise in the high-density cholesterol lipoprotein (HDL-cholesterol). Since the response of the HDL-subfractions to moderate or heavy dose of alcohol is less clear, we now compared the high-density lipoprotein cholesterol status between groups consuming different amounts of alcohol. In this population-based survey serum total high-density lipoprotein cholesterol and its HDL2 and HDL3 subfractions were blindly compared between 264 consecutive middle-aged men (37 teetotallers, 137 moderate drinkers, 90 heavy drinkers) participating in a voluntary health screening and 104 male alcoholics. Alcohol consumption correlated significantly (P < 0.001) with total HDL-cholesterol, HDL2, HDL3 when all subjects (n = 368) were included but the correlation disappeared when alcoholics were excluded (n = 264). In comparison with teetotallers, alcoholics had significantly higher total HDL-cholesterol, HDL2 and HDL3 values (P < 0.001). Moderate or heavy intake of alcohol had no effect on HDL2 but increased the HDL3-fraction. If the protective effect of moderate alcohol consumption is mediated by high-density lipoprotein, it may not be accounted for by changes in the HDL2-fraction. The observed increases in the concentration of the HDL3-fraction, however, suggest that this subfraction may not be inert with respect to coronary disease and could possibly have a role in the protective effect.

Apolipoprotein E phenotypes and plasma lipids in diabetic children and adolescents

Apolipoprotein E (apoE) polymorphism is a genetic determinant of serum lipoprotein levels and coronary heart disease risk. ApoE appears in three major isoforms E2, E3 and E4, coded by corresponding alleles epsilon 2, epsilon 3 and epsilon 4. These give six different phenotypes. Patients with insulin dependent diabetes (IDDM) have been reported to have increased incidence of E2/2 homozygosity. We studied the frequencies of apoE phenotypes and their association with plasma lipids in 201 diabetic children, aged 2-17 years, and in 216 healthy controls with the same age range. Phenotyping was performed directly from plasma by iso-electric focusing and immunoblotting. Plasma total and high density lipoprotein (HDL) cholesterol (C) and triglycerides were determined by routine laboratory methods. Apolipoprotein A1 (apoA1) and B (apoB) were measured by turbidometry. There were no differences in apoE phenotype or allele distributions between the diabetic and control subjects. The frequencies of epsilon 2, epsilon 3, and epsilon 4 in the diabetic and control children were 0.08 versus 0.07, 0.73 versus 0.72 and 0.19 versus 0.21. The difference in apoE2/2 frequencies (2.0 in diabetic and 0.5% in normal children) was not statistically significant. In the diabetic children, there was a distinct relation between apoE phenotype and plasma lipids; presence of apoE2 was associated with the lowest and that of apoE4 with the highest concentrations of total and low density lipoprotein (LDL) C, and apoB. Ratios of HDL-C/LDL-C and apoA1/apoB showed on opposite trend. The influence of apoE polymorphism on plasma lipids was less clear in the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of creatinine in serum and urine by cation-exchange high-pressure liquid chromatography

We describe an HPLC method for quantifying creatinine, separating the analyte from other compounds in serum and urine by cation-exchange chromatography and measuring its absorbance at 234 nm. The precision of the method (CV) varied from 2.9% (mean creatinine concentration, 31 mumol/L) to 1.7% (361 mumol/L) within a series of assays and from 3.9% (34 mumol/L) to 2.4% (391 mumol/L) between series. A comparison with the Jaffé method, as performed with a Technicon SMA analyzer, gave the regression line yHPLC = 1.00xJaffé - 12.0 (n = 141, r = 0.998, and Syx = 19). Results also are comparable with those of an enzymatic method, if the enzymatic method is standardized with a serum-based standard when serum samples are measured. An aqueous standard has to be used for enzymatic determination of creatinine in urine.

Late carotid restenosis: aetiologic factors for recurrent carotid artery stenosis during long-term follow-up

During a fourteen-year-period 257 patients underwent carotid endarterectomy in an unselected population of 700,000 inhabitants. The incidence of haemodynamically significant restenosis was 13.5% in 133 vessels in 116 patients studied by duplex scanning 28 to 209 months following carotid endarterectomy. The most striking differences between patent and restenosed cases were in serum cholesterol, triglyceride and HDL-cholesterol levels. The patients with a long-term low cholesterol (less than 6.5 mmol/l), low triglyceride (less than 1.42 mmol/l) and high HDL cholesterol (greater than 1.0 mmol/l) levels had significantly less high grade restenosis (P less than 0.05). Apolipoprotein A-I and B had no significant effect, but if the lowest limit of normal apolipoprotein A-I level was considered as 1.27 g/l the difference was significant. The frequency of a high-grade restenosis in patients with diabetes mellitus and coronary heart disease was not significantly increased, but supports the view that these are risk factors in the development of atherosclerotic changes in an operated carotid artery. The incidence of recurrent stenosis appears to be unrelated to hypertension, claudication, obesity, smoking, operative factors or to the indication for surgery. Men were more prone than women to get a high-grade restenosis. Postoperative treatment with acetylsalicylic acid was most effective, the incidence was only half of that expected, whereas the anticoagulants or a combination of acetylsalicylic acid and dipyridamole were of no benefit. Haematocrit, RBC, platelet count and thrombocrit were contradictory.

Urinary citrate excretion in patients with urolithiasis and normal subjects

Citrate is a normal constituent of urine which combines with calcium to form a soluble salt. Urinary citrate excretion was examined in patients with urolithiasis and normal subjects by a specific enzymatic technique. There was a considerable overlap in the urinary citrate excretion between normal subjects and stone-formers, but the citrate-creatinine ratio, the citrate-calcium ratio and the citrate-magnesium-calcium ratio, which were all highly significantly lower (p less than 0.001) in stone-formers than in controls, proved most reliable in discriminating between these groups.

Comparison of indirect diagnostic methods for hypolactasia

The aim of this study was to continue our previously published work and to compare the different indirect diagnostic methods for hypolactasia with the lactase to sucrase ratio obtained by jejunal biopsy. The following tests were performed in 63 adult patients: the breath hydrogen test, the lactose tolerance test with ethanol (serum galactose measurement after oral lactose load with ethanol), the urinary lactose tolerance test (urinary galactose measurement after oral lactose load with ethanol), and the strip test (like the former but using a special test strip for urinary galactose). Specificities of all these tests were good (96-98%). The 3-h breath hydrogen test was less sensitive (69%) than the other methods (81-94%). The strip test is recommended for the general practitioner for the diagnosis of this common cause of abdominal complaints.

Serum lipids in Finnish and Japanese postmenopausal women

Serum lipids were measured in 30 Finnish and Japanese postmenopausal women. Total cholesterol, HDL cholesterol, LDL cholesterol, apo B and the HDL cholesterol/apo A1 ratio were higher in Finnish than in Japanese women. The LDL cholesterol/apo B and apo A1/apo B ratios were lower in Finns than in Japanese. In serum phospholipids the percentage of arachidonic acid was higher and the percentage of the n - 3 fatty acids, eicosapentaenoic acid and docosahexaenoic acid, and the eicosapentaenoic acid/arachidonic acid ratio were lower in Finnish than in Japanese women. No significant correlations were found between serum oestrone levels and lipid parameters.