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M Laakso

Publications and source records attributed to M Laakso.

At least 181 records · Page 10Linked to original sources

Codon 54 polymorphism of the human intestinal fatty acid binding protein 2 gene is associated with dyslipidemias but not with insulin resistance in patients with familial combined hyperlipidemia.

Familial combined hyperlipidemia (FCHL) is associated with variable expression of dyslipidemias and insulin resistance. In nondiabetic Pima Indians an A to G substitution in codon 54 of the fatty acid binding protein 2 (FABP2) gene has been shown to be associated with insulin resistance. We screened the entire coding region of this gene by single-strand conformation polymorphism analysis in 24 probands (17 men and 7 women; age, 63.0 +/- 7.4 years [mean +/- SD]; body mass index [BMI], 27.7 +/- 4.2 kg/m2) who had FCHL and in 40 healthy men from a random population sample of 82 men (age, 54.0 +/- 5.0 years; BMI, 26.3 +/- 3.2 kg/m2). Insulin resistance was assessed with the euglycemic clamp in 58 subjects from FCHL families (14 probands with FCHL and 44 first-degree relatives of probands; 38 men and 20 women; age, 51.5 +/- 12.6 years; BMI, 25.5 +/- 3.9 kg/m2). We found three nucleotide substitution in the FABP2 gene: GCT to ACT (Ala-->Thr) in codon 54, GTA to GTG in codon 118, and GCGCA to GCACA in the 3'-noncoding region. Frequencies of these variants did not differ between the patients and control subjects. The Ala to Thr substitution in codon 54 was associated with a high lipid oxidation rate (P = .011 after adjustment for sex and family relationship), high HDL triglycerides (P = .042), and high LDL triglycerides (P = .013) but not with insulin resistance in subjects from FCHL families. The FABP2 gene is unlikely to be a major gene for FCHL, but it might affect lipid metabolism in subjects with FCHL.

Adult↗

Relationship of LDL size to insulin sensitivity in normoglycemic men.

A preponderance of small, dense LDL has been suggested to be more atherogenic than larger, more buoyant LDL. Although several studies have suggested associations of small, dense LDL with hyperinsulinemia, few data are available on the relation of small, dense LDL to insulin resistance. We examined the association of LDL particle size determined by gradient gel electrophoresis with the rates of whole-body glucose uptake (WBGU) as determined by the hyperinsulinemic euglycemic clamp with indirect calorimetry in 87 Finnish normoglycemic men. LDL size was significantly positively correlated with the rates of WBGU (overall, r = .31, P < .01; oxidative, r = .23, P < .05; and nonoxidative, r = .31, P < .01). Rates of WBGU were also significantly lower in subjects with small LDL particles (< or = 26.0 nm) compared with those in subjects with larger LDL particles (> 26.0 nm). This relation was not explained by obesity. Serum triglyceride concentrations were found to significantly affect the relationship of LDL particle size to WBGU. Specifically, LDL size was correlated with the rates of WBGU in men with mildly elevated triglyceride levels but not in men with low triglyceride levels. Serum VLDL triglyceride concentration was a substantially stronger determinant of LDL size than were the rates of WBGU. WBGU was not significantly related to LDL size when adjusted for triglycerides. We conclude that a preponderance of small, dense LDL particles is associated with insulin resistance and that serum triglyceride concentration modifies this relationship.

Body Mass Index↗

Leptin concentrations, sex hormones, and cortisol in nondiabetic men.

Leptin, the product of the human ob gene, is increased in obese individuals, suggesting resistance to its effect. However, there is a variability in leptin levels at each level of body mass index, suggesting that genetic and environmental factors other than overall adiposity may regulate leptin concentrations. No data currently exist on the relation of sex hormones to leptin concentrations in men. We examined the relation ofleptin levels to sex hormone-binding globulin, total and free testosterone, dehydroepiandrosterone sulfate, estradiol, and cortisol in 87 normoglycemic men. Leptin levels were significantly correlated with free testosterone (r = -0.14; P < 0.05), sex hormone-binding globulin (r = -0.26; P < 0.05), total testosterone (r = -0.32; P < 0.01), and cortisol (r = -0.09; P = NS). However, after adjustment for body mass index (or, alternatively, waist or hip circumference), leptin concentrations were not significantly related to sex hormones or cortisol. Our data suggest that in men, sex hormones are not important independent modifiers of leptin concentrations.

Body Mass Index↗

Variants in the human intestinal fatty acid binding protein 2 gene in obese subjects.

Fatty acid binding protein 2 gene (FABP2) has been proposed to be an important candidate gene for insulin resistance; therefore, it also could be a promising candidate gene for obesity. We screened the whole coding region of the FABP2 gene in 40 obese nondiabetic Finnish subjects. Furthermore, we investigated the effects of the codon 54 polymorphism of this gene (Ala-->Thr) on insulin levels and basal metabolic rate in 170 obese subjects. The frequencies of the variants found in exon 4 (GTA-->GTG) and 3'-noncoding region (GCGCA-->GCACA), as well as the allele frequencies for the variable lengths of the ATT repeat sequence in intron 2 did not differ between the obese subjects and nonobese controls. The frequency of threonine-encoding allele in codon 54 of the FABP2 gene did not differ between obese and control subjects (28 vs. 29%, respectively). In the obese group there were no differences in gender distribution, age, weight, body mass index, lean body mass, percentage of body fat, waist circumference, and waist-to-hip ratio among the individuals homozygous for Ala54, heterozygous for Thr54, and homozygous for Thr54-encoding alleles. Similarly, fasting serum insulin, glucose, lipids and lipoprotein concentrations, basal metabolic rate (adjusted for lean body mass and age), respiratory quotient, and rates of glucose and lipid oxidation did not differ among the groups. We conclude that obesity is not associated with specific variants in the FABP2 gene. Furthermore, the codon 54 Ala to Thr polymorphism of this gene does not influence insulin levels or basal metabolic rate in obese Finns.

Adult↗

The relation of proinsulin, insulin, and proinsulin-to-insulin ratio to insulin sensitivity and acute insulin response in normoglycemic subjects.

Plasma levels of proinsulin and its conversion intermediates are elevated in NIDDM patients. Recent studies have suggested that proinsulin levels are also increased relative to insulin levels in subjects who subsequently develop NIDDM. This may be due to insulin resistance or a defect in proinsulin processing or insulin secretion. If insulin resistance is the trigger, the proinsulin-to-insulin ratio would be higher in insulin-resistant subjects than in insulin-sensitive subjects. We examined the association of fasting proinsulin, 32,33 split proinsulin, and the proinsulin-to-insulin ratio with insulin sensitivity (SI), estimated by a frequently sampled intravenous glucose tolerance test and the minimal model in 138 normoglycemic subjects ages 53-61 years. We also investigated the relation of proinsulins and the proinsulin-to-insulin ratio to acute insulin response (AIR). Fasting specific insulin (r = -0.64), intact proinsulin (r = -0.43), and 32,33 split proinsulin (r = -0.54) concentrations were inversely correlated and the proinsulin-to-insulin ratio positively (r = 0.31) correlated with SI (P < 0.001). Fasting specific insulin (r = 0.64), intact proinsulin (r = 0.35), and 32,33 split proinsulin (r = 0.45) concentrations were positively correlated and proinsulin-to-insulin ratio (r = -0.40) inversely correlated with AIR (P < 0.001). The proinsulin-to-insulin ratio increased by increasing levels of SI (quartiles of SI from low to high: 0.048, 0.078, 0.078, 0.068; P = 0.012) and decreased by increasing AIR (quartiles of AIR from low to high: 0.088, 0.068, 0.058, 0.058; P = 0.005). These associations were independent of age, sex, BMI, and waist-to-hip ratio. Furthermore, the relation between the proinsulin-to-insulin ratio and AIR was independent of SI. In conclusion, in normoglycemic subjects, insulin resistance (low SI) was associated with a low rather than a high proinsulin-to-insulin ratio. Subjects who maintained normoglycemia with a low AIR had an increased proinsulin-to-insulin ratio compared with those who needed high AIR to maintain normoglycemia. These results suggest that, in subjects with normal glucose tolerance, insulin resistance does not induce increased proinsulin relative to insulin secretion, but rather is associated with enhanced processing of proinsulin.

Blood Glucose↗

Dyslipidemia and hyperglycemia predict coronary heart disease events in middle-aged patients with NIDDM.

Patients with NIDDM are at increased risk for coronary heart disease (CHD). However, information on the predictive value of cardiovascular risk factors and the degree of hyperglycemia with respect to the risk for CHD in diabetic patients is still limited. Therefore, we carried out a prospective study on risk factors for CHD, including a large number of NIDDM patients. At baseline, risk factor levels of CHD were determined in 1,059 NIDDM patients (581 men and 478 women), aged from 45 to 64 years. These patients were followed up to 7 years with respect to CHD events. Altogether, 158 NIDDM patients (97 men [16.7%] and 61 women [12.8%]) died of CHD and 256 NIDDM patients (156 men [26.8%] and 100 women [20.9%]) had a serious CHD event (death from CHD or nonfatal myocardial infarction). A previous history of myocardial infarction, low HDL cholesterol level (<1.0 mmol/l), high non-HDL cholesterol (> or =5.2 mmol/l), high total triglyceride level (>2.3 mmol/l), and high fasting plasma glucose (>13.4 mmol/l) were associated with a twofold increase in the risk of CHD mortality or morbidity, independently of other cardiovascular risk factors. High calculated LDL cholesterol level (> or =4.1 mmol/l) was significantly associated with all CHD events. The simultaneous presence of high fasting glucose (>13.4 mmol/l) with low HDL cholesterol, low HDL-to-total cholesterol ratio, or high total triglycerides further increased the risk for CHD events up to threefold. Our 7-year follow-up study provides evidence that dyslipidemia and poor glycemic control predict CHD mortality and morbidity in patients with NIDDM.

Blood Glucose↗

Polymorphism of the beta3-adrenergic receptor gene affects basal metabolic rate in obese Finns.

Low basal metabolic rate (BMR) is a risk factor for weight gain and obesity. The polymorphism at codon 64 of the beta3-adrenergic receptor gene has been suggested to be associated with BMR. We investigated the frequency of the Trp64Arg of the beta3-adrenergic receptor gene and the effects of this polymorphism on BMR in obese Finns. Altogether, 170 obese subjects (29 men, 141 women, BMI 34.7 +/- 3.8 kg/m2, mean +/- SD) participated in the study. The frequency of the Trp64Arg polymorphism was 19%. None of the obese subjects were homozygous for the Arg-encoding allele. The frequency of the Trp64Arg polymorphism in obese Finns did not differ from nonobese and normoglycemic control subjects. BMR adjusted for lean body mass and age was lower in subjects with the Trp64Arg polymorphism (n = 20) than in normal homozygotes Trp64Trp (n = 99) (1,569 +/- 73 vs. 1,635 +/- 142 kcal/day, P = 0.004). For the female group (n = 98), the respective values were 1,501 +/- 66 kcal/day vs. 1,568 +/- 127 kcal/day (P = 0.004). There were no significant differences in weight, BMI, waist-to-hip ratio, lean body mass, percentage of fat, and respiratory quotient between the groups with or without the Trp64Arg polymorphism. Neither serum glucose nor insulin levels differed between the two groups. We conclude that the Trp64Arg polymorphism of the beta3-adrenergic receptor gene affects basal metabolic rate in obese Finns but does not have significant effect on glucose metabolism.

Adult↗

The Trp64Arg polymorphism of the beta 3-Adrenergic receptor gene. Lack of association with NIDDM and features of insulin resistance syndrome.

OBJECTIVE: To investigate the association of the Trp64Arg polymorphism of the beta3-adrenergic receptor gene with NIDDM and the features of insulin resistance syndrome in subjects from eastern Finland. RESEARCH DESIGN AND METHODS: We determined the prevalence of the Trp64Arg polymorphism of the beta3-adrenergic receptor gene by restriction fragment length polymorphism analysis in 110 patients with NIDDM (54 men and 56 women, age 63 +/- 1 years, BMI 30.4 +/- 0.5 kg/m2), in 183 patients with features of insulin resistance syndrome (103 men and 80 women, age 44 +/- 0 years, BMI 31.1 +/- 0.4 kb/m2), and in 82 normoglycemic control men (age 54 +/- 1 years, BMI 26.3 +/- 0.4 kg/m2). RESULTS: The allele frequency of the Trp64Arg polymorphism of the beta3-adrenergic receptor gene was similar in patients with NIDDM, in patients with insulin resistance syndrome, and in control subjects (0.08, 0.07, and 0.07, respectively; NS). In addition, this polymorphism was not associated with low resting metabolic rate, abdominal obesity, increased lipid oxidation, hypertension, or earlier development of NIDDM as previously described. Furthermore, in 82 normoglycemic male control subjects the Trp64Arg polymorphism was not associated with insulin resistance evaluated by the euglycemic-hyperinsulinemic clamp. CONCLUSIONS: The Trp64Arg polymorphism of the beta 3-adrenergic receptor gene is unlikely to be a major genetic predisposer to NIDDM or insulin resistance syndrome in subjects from eastern Finland.

Adult↗

ERPs reveal deficits in automatic cerebral stimulus processing in patients with NIDDM.

We compared auditory event-related potentials (ERPs) and neuropsychological test scores in nine patients with non-insulin-dependent diabetes mellitus (NIDDM) and in nine control subjects. The measures of automatic stimulus processing, habituation of auditory N100 and mismatch negativity (MMN) were impaired in patients. No differences were observed in the N2b and P3 components, which presumably reflect conscious cognitive analysis of the stimuli. A trend towards impaired performance in the Digit Span backward was found in diabetic subjects, but in the tests of secondary or long-term memory the groups were comparable. Patients with NIDDM may have defects in arousal and in the automatic ability to redirect attention, which can affect their cognitive performance.

Acoustic Stimulation↗

Femoral atherosclerosis in middle-aged subjects: association with cardiovascular risk factors and insulin resistance.

The aim of this 8-year follow-up study was to investigate the role of conventional cardiovascular risk factors as predictors for asymptomatic femoral atherosclerosis. The authors also evaluated the association of insulin resistance with atherosclerosis in a cross-sectional setting. Cardiovascular risk factors of 118 subjects were studied at the baseline study in 1983-1985 in Kuopio, Finland. Femoral atherosclerosis, defined as a presence of plaques, was investigated by ultrasonography in the follow-up study in 1992-1993. In the univariate logistic regression analyses, age (p = 0.002), systolic and diastolic blood pressure (p = 0.002 and p = 0.013, respectively), total cholesterol (p = 0.005), low density lipoprotein (LDL) cholesterol (p = 0.005), total triglycerides (p = 0.033), LDL triglycerides (p = 0.033), apolipoprotein B (p = 0.045), and fasting plasma glucose (p = 0.011) had a significant association with the presence of femoral plaques. Plasma insulin levels and insulin sensitivity index, determined in 87 subjects by an intravenous glucose tolerance test and minimal model at the follow-up study, were not associated with femoral plaques. The results demonstrate that atherogenic lipid and lipoprotein pattern and blood pressure are strongly associated with femoral atherosclerosis, whereas insulin sensitivity and hyperinsulinemia seem not to play such a significant role.

Adult↗

Memory functions in human subjects with different apolipoprotein E phenotypes during a 3-year population-based follow-up study.

The apolipoprotein E epsilon4 allele is the most common risk factor for Alzheimer's disease (AD). The epsilon2 allele may play a protective role in AD. Our previous cross-sectional study showed that in non-demented elderly subjects the epsilon2 allele is associated with better learning ability than other alleles. We wished to investigate the influence of different apolipoprotein E (apoE) phenotypes on cognitive functions in a 3-year follow-up study starting with a random sample of 917 non demented elderly subjects. Episodic memory was examined with the List Learning Test (Buschke's selective reminding method), as well as with immediate and delayed recall of figures. Retrieval from semantic memory was assessed with the Category and Verbal Fluency tests. Constructional abilities were examined by copying figures. Attention functions were examined with the Trail Making A and B tests. A total of 632 subjects completed the 3-year follow-up study. The subjects with apoE phenotypes E2/2 or E2/3 were able to maintain their verbal learning performance, while the learning ability of the subjects with other apoE phenotypes deteriorated. We suggest that successful mental aging may be at least in part associated with genetic factors.

Aged↗

Glycemic control and the risk for coronary heart disease in patients with non-insulin-dependent diabetes mellitus. The Finnish studies.

PURPOSE: To review population-based studies that investigated the association and nature of association between glycemic control and the risk for coronary heart disease in patients with non-insulin-dependent diabetes mellitus (NIDDM). DATA SOURCES: Study 1 included 133 newly diagnosed patients with NIDDM from eastern Finland, who were 45 to 64 years of age at baseline. These patients were followed up to 10 years for cardiovascular mortality. Study 2 included 229 newly or previously diagnosed patients with NIDDM from eastern Finland, aged 65 to 74 years at baseline. These patients were followed up to 3.5 years for coronary heart disease mortality and all coronary heart disease events (mortality or nonfatal myocardial infarction). STUDY SELECTION: Prospective, population-based studies that included indicators of glycemic control and the evaluation of coronary heart disease and cardiovascular risk. RESULTS: Study 1: 10-year cardiovascular mortality was significantly and linearly associated with glycemic control (fasting blood glucose and glycated hemoglobin A1 levels) independently of the mode of treatment. A high fasting blood glucose level significantly predicted cardiovascular mortality in multiple logistic regression analysis independently of other risk factors. Study 2: Glycated hemoglobin A1c was the most important single risk factor associated with coronary heart disease death or all coronary heart disease events. In multiple logistic regression analysis, glycated hemoglobin A1c was significantly associated with coronary heart disease death after adjustment for other cardiovascular risk factors. CONCLUSIONS: Two prospective, population-based studies from Finland give evidence for the linear association of glycemic control with the risk for coronary heart disease in middle-aged and elderly patients with NIDDM.

Aged↗

Family history of coronary heart disease is a stronger predictor of coronary heart disease morbidity and mortality than family history of non-insulin dependent diabetes mellitus.

The aim of this study was to compare the effect of family history of non-insulin dependent diabetes mellitus (NIDDM) and coronary heart disease (CHD) as risk factors for CHD morbidity and mortality. Altogether, 394 siblings of NIDDM probands and non-diabetic probands, with and without CHD, were followed for 8 years with respect to CHD events in a prospective population-based study. The baseline study was conducted from 1983 to 1985. Age- and sex-adjusted cumulative occurrence of CHD events was higher in the siblings of the probands with CHD and with NIDDM (13.1%; P = 0.037) and in the siblings of the probands with CHD and without NIDDM (15.4%; P = 0.054), compared with the siblings of the probands without NIDDM and without CHD (4.8%). The incidence of fatal CHD events tended to be higher in a group with a family history of NIDDM and CHD, but the trend was not statistically significant. In univariate logistic regression analyses, a family history of CHD was positively associated with cumulative occurrence of CHD events (odds ratio 2.53, P = 0.009), whereas a family history of NIDDM had no significant association (odds ratio 1.39, P = 0.312). After adjustment for age, sex, family history of NIDDM and major cardiovascular risk factors, the association between family history of CHD and cumulative occurrence of CHD events remained significant (odds ratio 2.25, P = 0.048). In conclusion, the present study indicates that a family history of CHD is a stronger predictor of future CHD events than a family history of NIDDM.

Aged↗

Monitoring the action of clodronate with type I collagen metabolites in multiple myeloma.

In our previous double-blind trial, we reported that clodronate reduced the incidence of bone lesions, fractures, pain and hypercalcaemia in multiple myeloma. Recently, it has been assumed that the antiresorptive effect of bisphosphonates on the osteoclasts is mediated through the osteoblasts. We therefore determined, in 244 patients of the same trial, serum assays of aminoterminal propeptide of type I procollagen (PINP) and type I collagen degradation product (ICTP). PINP is an early synthesis product of proliferating osteoblasts, in comparison to the alkaline phosphatase (AP) which is secreted by differentiated osteoblasts during the maturation phase of collagen. ICTP circulates in serum when old bone is resorbed. Our results indicate that after 25 months, the PINP levels decreased in the clodronate group (from 68.9 +/- 4.4 micrograms/l to 37.2 +/- 3.5 micrograms/l; P < 0.001) but not in the control group (from 61.5 +/- 3.2 micrograms/l to 69.3 +/- 7.5 micrograms/l; P < NS). The fall in the ICTP levels was markedly steeper in the patients receiving clodronate (from 8.38 +/- 0.80 micrograms/l to 4.58 +/- 0.32 micrograms/l; P < 0.01) than placebo (from 7.84 +/- 0.53 micrograms/l to 6.45 +/- 0.95 micrograms/l; P = NS). A significant difference between the study groups was seen at 4 months in the PINP, at 7 months in the ICTP and at 13 months in the AP levels, suggesting that clodronate affected through the proliferating osteoblasts, the osteoclasts, and through the osteoclasts, the differentiated osteoblasts. High baseline ICTP, PINP and AP levels indicated a poor prognosis. The decrease of the markers by clodronate was more marked in survivors than in non-survivors.

Aged↗

Soluble interleukin-6 receptor as a prognostic factor in multiple myeloma. Finnish Leukaemia Group.

Interleukin-6 (IL-6) is a major growth factor for the clonal malignant plasma cells in multiple myeloma (MM). The effect of IL-6 may be enhanced by soluble IL-6 receptor (sIL-6R). As there is a clinical need for improved stratification of MM patients at diagnosis, we have studied the role of sIL-6R as a prognostic marker in 207 newly diagnosed MM patients. Serum sIL-6R concentration was above the upper reference limit in 47% of the patients at diagnosis. The concentrations of sIL-6R and two other prognostic factors, IL-6 and beta-2 microglobulin (beta 2M), were all significantly higher in the patients who died within 3 years compared with those who survived. However, serum sIL-6R did not show linear correlation with IL-6 or beta 2M levels. In univariate logistic regression analysis sIL-6R was a significant predictor of 3-year mortality. Kaplan-Meier analysis showed that raised levels of sIL-6r were associated with shorter survival. When the patients were stratified into four groups according to their serum IL-6 and sIL-6R levels the patients with normal serum levels of both parameters had clear survival benefit. As beta 2M was the most powerful prognostic factor in the multivariate analysis, the patients were also stratified according to their serum beta 2M and sIL-6R levels. The patients with raised levels of both beta 2M and sIL-6R had shorter survival than the patients in the other three groups. Thus, measurement of these parameters at diagnosis would help to stratify MM patients.

Adult↗