1. |
- Kilpeläinen, Tuomas O, et al.
(författare)
-
Genome-wide meta-analysis uncovers novel loci influencing circulating leptin levels
- 2016
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- Leptin is an adipocyte-secreted hormone, the circulating levels of which correlate closely with overall adiposity. Although rare mutations in the leptin (LEP) gene are well known to cause leptin deficiency and severe obesity, no common loci regulating circulating leptin levels have been uncovered. Therefore, we performed a genome-wide association study (GWAS) of circulating leptin levels from 32,161 individuals and followed up loci reaching P<10(-6) in 19,979 additional individuals. We identify five loci robustly associated (P<5 × 10(-8)) with leptin levels in/near LEP, SLC32A1, GCKR, CCNL1 and FTO. Although the association of the FTO obesity locus with leptin levels is abolished by adjustment for BMI, associations of the four other loci are independent of adiposity. The GCKR locus was found associated with multiple metabolic traits in previous GWAS and the CCNL1 locus with birth weight. Knockdown experiments in mouse adipose tissue explants show convincing evidence for adipogenin, a regulator of adipocyte differentiation, as the novel causal gene in the SLC32A1 locus influencing leptin levels. Our findings provide novel insights into the regulation of leptin production by adipose tissue and open new avenues for examining the influence of variation in leptin levels on adiposity and metabolic health.
|
|
2. |
- Eriksson, Maria, 1965-, et al.
(författare)
-
Improved fibrinolytic activity during exercise may be an effect of the adipocyte-derived hormones leptin and adiponectin
- 2008
-
Ingår i: Thrombosis Research. - : Elsevier. - 0049-3848 .- 1879-2472. ; 122:5, s. 701-708
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Physical activity is associated with improved fibrinolytic activity and reduced risk for cardiovascular disease. High levels of leptin and low levels of adiponectin, both adipocyte-derived hormones, or adipokines, are related to dysfibrinolysis and risk for cardiovascular disease. In this study, we explored if improved fibrinolytic activity during exercise could be linked to changes in leptin and adiponectin levels.MATERIALS AND METHODS: Twenty healthy men (mean age 36 years) participated in a 14-day long skiing expedition in the Swedish mountains. They were randomly assigned to either a 40% or a 30% fat-based diet. Anthropometry, lipids, fibrinolytic activity (PAI-1 activity, tPA activity and mass) and adipokines (leptin and adiponectin) were measured before, during and six weeks after the expedition.RESULTS: PAI-1 activity and circulating levels of leptin decreased whereas levels of adiponectin increased during exercise. The fall in PAI-1 activity showed a strong linear association with changes in leptin and adiponectin levels (p = 0.001 and p < 0.001, respectively). Changes in leptin and adiponectin levels were independent of decreasing waist circumference. However, the association between anthropometric measures and adipokines changed considerably during the expedition. Adiponectin was weakly and negatively associated with BMI at baseline. In contrast, there was a strong positive association between adiponectin and BMI after two weeks of exercise, whereas the association between leptin and BMI became less pronounced. In addition, increasing leptin and decreasing adiponectin levels were associated with increasing PAI-1 activity during the six weeks following the expedition. After six weeks of normal activity, fibrinolytic activity and hormone levels returned towards baseline levels.CONCLUSION: Heavy exercise induced improved fibrinolytic activity, which was associated independently with changes in circulating levels of the adipocyte-derived hormones leptin and adiponectin. Improved fibrinolytic activity (and reduced risk for cardiovascular disease) related to physical activity could possibly be mediated by leptin and adiponectin.
|
|
3. |
|
|
4. |
- Hallmans, Göran, et al.
(författare)
-
Cardiovascular disease and diabetes in the Northern Sweden Health and Disease Study Cohort : evaluation of risk factors and their interactions.
- 2003
-
Ingår i: Scandinavian Journal of Public Health. Supplement Links. - : SAGE Publications. - 1403-4956 .- 1403-4948 .- 1651-1905. ; 61, s. 18-24
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of this paper is, first, to describe the organization, sampling procedures, availability of samples/database, ethical considerations, and quality control program of the Northern Sweden Health and Disease Study Cohort. Secondly, some examples are given of studies on cardiovascular disease and diabetes with a focus on the biomarker programme. The cohort has been positioned as a national and international resource for scientific research.
|
|
5. |
- Jacobson, Sofie, et al.
(författare)
-
Leptin independently predicts development of future sepsis and determines survival in the acute phase
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Objective: To determine if levels of the adipocyte-derived hormones leptin and adiponectin (adipokines) predict sepsis development and if intra-individual changes in circulating levels from baseline to the acute phase affect outcome.Method: A nested case-referent study within the framework of the Northern Sweden Health and Disease Study (NSHDS) and the Northern Sweden Maternity Cohort (NSMC). Patients aged 18 years or more with documented sepsis within 24 hours after admission to the intensive care unit (ICU) were included if they had participated in a health survey and donated blood samples prior to the sepsis event, and if possible also had stored plasma from the acute phase. Two matched referents free of known sepsis were selected for each case. Baseline and acute phase plasma leptin and adiponectin levels were determined. The associations between adipokines and sepsis and its severity and outcome were determined.Results: We identified 57 men and 97 women with a first-time sepsis event 6.5 years (median with IQR 7.7) after participation in the health survey, and 83% of them had also samples from the acute septic phase. Hyperleptinemia associated with a future sepsis event (OR 1.77, 95% CI 1.04-3.00, P=0.03), with stronger associations with severe sepsis and septic shock than with sepsis. High leptin levels were also associated with hospital death in the fully adjusted model. Leptin remained associated with sepsis in men (P=0.02), but not in women (P=0.36), after stratification and adjustment for BMI. In the acute phase, leptin increased more in men than in women (P=0.001), and high leptin levels were associated with increased risk for in-hospital death in women (OR 4.18, 95%CI 1.17-15.00, P=0.03), while being protective in men (OR 0.05, 95% CI 0.01-0.48, P=0.01). Adiponectin did not associate with sepsis or outcome.Conclusions: Hyperleptinemia independently predicted the development of sepsis, and an unfavourable outcome in men. Adiponectin was not associated with sepsis development.
|
|
6. |
- Jacobson, Sofie, et al.
(författare)
-
Levels of mannose-binding lectin (MBL) predicts sepsis and associates with sepsis-related in-hospital mortality differentially in men and women
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Objective: To determine if levels of mannose-binding lectin (MBL) predict sepsis development and if intra-individual changes in circulating levels from baseline to the acute septic phase associate with in-hospital mortality.Method: A nested case-referent study within the framework of the Northern Sweden Health and Disease Study (NSHDS) and the Northern Sweden Maternity Cohort (NSMC). Patients aged 18 years or more with documented sepsis within 24 hours after admission to the intensive care unit were included if they had participated in a health survey and donated blood samples prior to the sepsis event. A subset of these patients had stored plasma also from the acute phase. Two matched referents free of known sepsis were selected for each case. Baseline and acute phase plasma MBL levels were determined. The association between MBL and sepsis, sepsis severity and in-hospital mortality were determined.Results: We identified 57 men and 95 women with a first-time sepsis event 6.5 years (median with IQR 7.7) after participation in a health survey, of which 127 also had samples from the acute septic phase. High baseline levels predicted future sepsis (OR 1.81, 95% CI 1.01-3.26), but were not associated with severity of sepsis or in-hospital fatality. Both high MBL levels in the acute phase (OR 4.94, 95% CI 1.44-16.89), and an increase from base line to the acute phase (OR 3.67, 95% CI 1.19-11.28) were associated with increased risk for in-hospital death in women, but not in men (OR 0.71, 95% CI 0.18-2.88). Low levels at baseline were not associated with future sepsis. Neither low levels at baseline, nor in the acute phase were associated with sepsis severity or in-hospital mortality.Conclusions: High pre-sepsis levels predicted a future sepsis event, and an increase from baseline to the acute phase as well as high levels in the acute phase associated with an unfavourable outcome in women.
|
|
7. |
- Jacobsson, Sofie, et al.
(författare)
-
Leptin independently predicts development of sepsis and its outcome
- 2017
-
Ingår i: Journal of Inflammation. - London : BioMed Central (BMC). - 1476-9255. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Sepsis is a life-threatening condition and obesity is related to the clinical outcome. The underlying reasons are incompletely understood, but the adipocyte derived hormones leptin and adiponectin may be involved.Methods: Patients aged 18 years or more with documented first time sepsis events were included in a nested case-referent study if they had participated in previous health surveys. Two matched referents free of known sepsis were identified. Circulating levels of leptin and adiponectin were determined in stored plasma, and their impact on a future sepsis event and its outcome was evaluated.Results: We identified 152 patients (62% women) with a sepsis event and a previous participation in a health survey. Eighty-three % had also blood samples from the acute event. Hyperleptinemia at health survey associated with a future sepsis event (OR 1.77, 95% CI 1.04-3.00) and with hospital death. After adjustment for BMI leptin remained associated with sepsis in men, but not in women. High levels in the acute phase associated with increased risk for in hospital death in women (OR 4.18, 95% CI 1.17-15.00), while being protective in men (OR 0.05, 95% CI 0.01-0.48). Furthermore, leptin increased more from baseline to the acute phase in men than in women. Adiponectin did not predict sepsis and did not relate to outcome.Conclusions: Hyperleptinemia independently predicted the development of sepsis and an unfavourable outcome in men, and inertia in the acute response related to worse outcome.
|
|
8. |
- Kaaks, Rudolf, et al.
(författare)
-
Prospective study of IGF-I, IGF-binding proteins, and breast cancer risk, in Northern and Southern Sweden
- 2002
-
Ingår i: Cancer Causes and Control. - 1573-7225 .- 0957-5243. ; 13:4, s. 307-316
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: To examine the possible relationships of breast cancer risk to prediagnostic plasma levels of insulin; insulin-like growth factor-I (IGF-I); and IGF-binding proteins -1, -2, and -3. Methods: Within two prospective cohorts in Umea and Malmo we measured plasma concentrations of insulin, IGF-I, and IGFBPs for a total of 513 incident breast cancer cases and 987 matched controls. Results: Globally, risk was unassociated with levels of IGF-I, IGFBP-3, or IGF-I adjusted for IGFBP-3. When breaking down the analysis by subgroups of age at blood donation, an increase in risk was observed for increasing levels of IGF-I in women aged 55 or older, in the Umea cohort only (odds ratios of 1.00, 1.73, 1.76, 1.90; p(trend) = 0.05). This effect weakened, however, when the analysis was restricted to subjects who did not use exogenous hormones for the treatment of menopausal symptoms. Levels of IGF-I and IGFBP-3 were not related to risk in younger women, recruited before age 50, contrary to observations from previous studies. In a subcohort where blood samples had been collected after at least four hours of fasting, breast cancer risk showed no clear associations with levels of insulin, IGFBP-1, or IGFBP-2. Conclusions: Our results do not confirm earlier findings of an association of plasma IGF-I levels with breast cancer risk especially in young women, but suggest a possible association with postmenopausal breast cancer risk, possibly among ERT/HRT users only. Our results do not support the hypothesis that elevated plasma insulin levels, and reduced levels of IGFBP-1 and IGFBP-2, are associated with increased breast cancer risk.
|
|
9. |
- Lindahl, Bernt, et al.
(författare)
-
A randomized lifestyle intervention with 5-year follow-up in subjects with impaired glucose tolerance : pronounced short-term impact but long-term adherence problems
- 2009
-
Ingår i: Scandinavian Journal of Public Health. - : SAGE Publications. - 1403-4948 .- 1651-1905. ; 37:4, s. 434-442
-
Tidskriftsartikel (refereegranskat)abstract
- AIMS: To compare data on cardiovascular risk factor changes in lipids, insulin, proinsulin, fibrinolysis, leptin and C-reactive protein, and on diabetes incidence, in relation to changes in lifestyle. METHODS: The study was a randomized lifestyle intervention trial conducted in northern Sweden between 1995 and 2000, in 168 individuals with impaired glucose tolerance (IGT) and body mass index above 27 at start. The intensive intervention group (n = 83) was subjected to a 1-month residential lifestyle programme. The usual care group (n = 85) participated in a health examination ending with a single counselling session. Follow-up was conducted at 1, 3 and 5 years. RESULTS: At 1-year follow-up, an extensive cardio-metabolic risk factor reduction was demonstrated in the intensive intervention group, along with a 70% decrease of progress to type 2 diabetes. At 5-year follow-up, most of these beneficial effects had disappeared. Reported physical activity and fibre intake as well as high-density lipoprotein cholesterol were still increased, and fasting insulin and proinsulin were lower. CONCLUSIONS: The intervention affected several important cardio-metabolic risk variables beneficially, and reduced the risk for type 2 diabetes, but the effects persisted only as long as the new lifestyle was maintained. Increased physical activity seemed to be the behaviour that was most easy to preserve.
|
|
10. |
- Lukanova, Annekatrin, et al.
(författare)
-
Nonlinear relationship of insulin-like growth factor (IGF)-I and IGF-I/IGF-binding protein-3 ratio with indices of adiposity and plasma insulin concentrations (Sweden).
- 2002
-
Ingår i: Cancer Causes and Control. - 0957-5243 .- 1573-7225. ; 13:6, s. 509-516
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: In this study we test the hypothesis of a nonlinear relationship of IGF-I with indices of body fat such as body mass index (BMI), insulin, and leptin.METHODS: The controls used in three case-control cancer studies nested in the Northern Sweden Health and Disease Cohort, were combined for this analysis. Measurements of plasma IGF-I, IGFBP-3, insulin, and leptin were available for 445 men and 391 women.RESULTS: In both men and women we found the highest mean IGF-I levels in subjects with BMI between 24 and 26. IGF-I concentrations decreased toward BMI < or = 20 and BMI > 30 in men; however, the results for women did not reach statistical significance. The molar ratio of IGF-I/IGFBP-3 showed a similar profile to that of IGF-I, although much less pronounced. The observed peak mean IGF-I levels in the second quintiles of insulin and leptin in men supported these findings. No significant variation of mean IGF-I levels across quintiles of insulin and leptin were observed in women.CONCLUSIONS: The results of this study provide evidence that IGF-I plasma concentrations vary substantially over a wide range of body weight and that the relationship is nonlinear.
|
|