| 1. |
- Akbari, Camilla, et al.
(författare)
-
Long-term major adverse liver outcomes in 1,260 patients with non-cirrhotic NAFLD
- 2024
-
Ingår i: JHEP Reports. - : Elsevier. - 2589-5559. ; 6:2
-
Tidskriftsartikel (refereegranskat)abstract
- Background & AimsLong-term studies of the prognosis of NAFLD are scarce. Here, we investigated the risk of major adverse liver outcomes (MALO) in a large cohort of patients with NAFLD.MethodsWe conducted a cohort study with data from Swedish university hospitals. Patients (n = 1,260) with NAFLD without cirrhosis were diagnosed through biopsy or radiology, and had fibrosis estimated through vibration-controlled transient elastography, biopsy, or FIB-4 score between 1974 and 2020 and followed up through 2020. Each patient was matched on age, sex, and municipality with up to 10 reference individuals from the general population (n = 12,529). MALO were ascertained from Swedish national registers. The rate of events was estimated by Cox regression.ResultsMALO occurred in 111 (8.8%, incidence rate = 5.9/1,000 person-years) patients with NAFLD and 197 (1.6%, incidence rate = 1.0/1,000 person-years) reference individuals during a median follow up of 13 years. The rate of MALO was higher in patients with NAFLD (hazard ratio = 6.6; 95% CI = 5.2–8.5). The risk of MALO was highly associated with the stage of fibrosis at diagnosis. In the biopsy subcohort (72% of total sample), there was no difference in risk between patients with and without non-alcoholic steatohepatitis. The 20-year cumulative incidences of MALO were 2% for the reference population, 3% for patients with F0, and 35% for F3. Prognostic information from biopsy was comparable to FIB-4 (C-indices around 0.73 vs. 0.72 at 10 years).ConclusionsThis study provides updated information on the natural history of NAFLD, showing a high rate of progression to cirrhosis in F3 and a similar prognostic capacity of non-invasive tests to liver biopsy.Impact and implicationsSeveral implications for clinical care and future research may be noted based on these results. First, the risk estimates for cirrhosis development are important when communicating risk to patients and deciding on clinical monitoring and treatment. Estimates can also be used in updated health-economic evaluations, and for regulatory agencies. Second, our results again highlight the low predictive information obtained from ascertaining NASHstatus by histology and call for more objective means by which to define NASH. Such methods may include artificial intelligence-supported digital pathology. We highlight that NASH is most likely the causal factor for fibrosis progression in NAFLD, but the subjective definition makes the prognostic value of a histological NASH diagnosis of limited value. Third, the finding that prognostic information from biopsy and the very simple Fibrosis-4 score were comparable is important as it may lead to fewer biopsies and further move the field towards non-invasive means by which to define fibrosis and, importantly, use non-invasive tests as outcomes in clinical trials. However, all modalities had modest discriminatory capacity and new risk stratification systems are needed in NAFLD. Repeated measures of non-invasive scores may be a potential solution.
|
|
| 2. |
- Bauzá-Thorbrügge, Marco, et al.
(författare)
-
Adipocyte-specific ablation of the Ca2+ pump SERCA2 impairs whole-body metabolic function and reveals the diverse metabolic flexibility of white and brown adipose tissue.
- 2022
-
Ingår i: Molecular metabolism. - : Elsevier BV. - 2212-8778. ; 63
-
Tidskriftsartikel (refereegranskat)abstract
- Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) transports Ca2+ from the cytosol into the endoplasmic retitculum (ER) and is essential for appropriate regulation of intracellular Ca2+ homeostasis. The objective of this study was to test the hypothesis that SERCA pumps are involved in the regulation of white adipocyte hormone secretion and other aspects of adipose tissue function and that this control is disturbed in obesity-induced type-2 diabetes.SERCA expression was measured in isolated human and mouse adipocytes as well as in whole mouse adipose tissue by Western blot and RT-qPCR. To test the significance of SERCA2 in adipocyte functionality and whole-body metabolism, we generated adipocyte-specific SERCA2 knockout mice. The mice were metabolically phenotyped by glucose tolerance and tracer studies, histological analyses, measurements of glucose-stimulated insulin release in isolated islets, and gene/protein expression analyses. We also tested the effect of pharmacological SERCA inhibition and genetic SERCA2 ablation in cultured adipocytes. Intracellular and mitochondrial Ca2+ levels were recorded with dual-wavelength ratio imaging and mitochondrial function was assessed by Seahorse technology.We demonstrate that SERCA2 is downregulated in white adipocytes from patients with obesity and type-2 diabetes as well as in adipocytes from diet-induced obese mice. SERCA2-ablated adipocytes display disturbed Ca2+ homeostasis associated with upregulated ER stress markers and impaired hormone release. These adipocyte alterations are linked to mild lipodystrophy, reduced adiponectin levels, and impaired glucose tolerance. Interestingly, adipocyte-specific SERCA2 ablation leads to increased glucose uptake in white adipose tissue while the glucose uptake is reduced in brown adipose tissue. This dichotomous effect on glucose uptake is due to differently regulated mitochondrial function. In white adipocytes, SERCA2 deficiency triggers an adaptive increase in fibroblast growth factor 21 (FGF21), increased mitochondrial uncoupling protein 1 (UCP1) levels, and increased oxygen consumption rate (OCR). In contrast, brown SERCA2 null adipocytes display reduced OCR despite increased mitochondrial content and UCP1 levels compared to wild type controls.Our data suggest causal links between reduced white adipocyte SERCA2 levels, deranged adipocyte Ca2+ homeostasis, adipose tissue dysfunction and type-2 diabetes.
|
|
| 3. |
- Dybjer, E., et al.
(författare)
-
Incretin hormones, insulin, glucagon and advanced glycation end products in relation to cognitive function in older people with and without diabetes, a population-based study
- 2020
-
Ingår i: Diabetic Medicine. - : Wiley. - 0742-3071 .- 1464-5491. ; 37:7, s. 1157-1166
-
Tidskriftsartikel (refereegranskat)abstract
- Aim The aim of this observational study was to investigate relationships between physiological levels of glucometabolic biomarkers and cognitive test results in a population-based setting. Methods Cross-sectional data were obtained from the Swedish population-based Malmo Diet and Cancer Study Re-examination 2007-2012 comprising 3001 older people (mean age 72 years). Through oral glucose tolerance testing (OGTT), fasting and post-load levels of serum insulin, plasma glucagon, serum glucose-dependent insulinotropic peptide (GIP) and plasma glucagon-like peptide-1 (GLP-1) were measured. Insulin resistance and insulin sensitivity levels were calculated. In 454 participants, advanced glycation end products (AGEs) were estimated through skin autofluorescence. Associations between biomarkers and two cognitive tests, the Mini-Mental State Examination (MMSE) and A Quick Test of Cognitive Speed (AQT) respectively, were explored in multiple regression analyses. Results Positive associations following adjustments for known prognostic factors were found between MMSE scores and insulin sensitivity (B = 0.822, P = 0.004), 2-h plasma glucagon (B = 0.596, P = 0.026), 2-h serum GIP (B = 0.581, P = 0.040) and 2-h plasma GLP-1 (B = 0.585, P = 0.038), whereas negative associations were found between MMSE scores and insulin resistance (B = -0.734, P = 0.006), fasting plasma GLP-1 (B = -0.544, P = 0.033) and AGEs (B = -1.459, P = 0.030) were found. Conclusions Higher levels of insulin sensitivity, GIP and GLP-1 were associated with better cognitive outcomes, but AGEs were associated with worse outcomes, supporting evidence from preclinical studies. Glucagon was linked to better outcomes, which could possibly reflect neuroprotective properties similar to the related biomarker GLP-1 which has similar intracellular properties. Longitudinal and interventional studies are needed to further evaluate neuromodulating effects of these biomarkers. presented at the European Association for the Study of Diabetes (EASD) 2019, Barcelona, Spain
|
|
| 4. |
- Hagström, Hannes, et al.
(författare)
-
Low to moderate lifetime alcohol consumption is associated with less advanced stages of fibrosis in non-alcoholic fatty liver disease
- 2017
-
Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 52:2, s. 159-165
-
Tidskriftsartikel (refereegranskat)abstract
- Background and aim: Moderate alcohol consumption has been associated with a lower risk of disease severity in non-alcoholic fatty liver disease (NAFLD). It is unclear if this reflects current or lifetime drinking, or can be attributed to confounders such as diet and exercise. We evaluated the impact of lifetime alcohol consumption on fibrosis severity in NAFLD. Methods: We prospectively enrolled 120 subjects with biopsy-proven NAFLD and through detailed questionnaires examined lifetime alcohol consumption, diet and physical activity. Main outcome measures were odds ratios (OR) for fibrosis stage, calculated through ordinal regression after adjustment for body mass index, diabetes mellitus type 2, smoking and age at biopsy. A biomarker for recent alcohol consumption, phosphatidyl ethanol (PEth) was sampled. Results: An increase in median weekly alcohol consumption to a maximum of 13 drinks per week was associated with lower fibrosis stage (adjusted OR for each incremental unit, 0.86; 95% CI, 0.76-0.97; p = .017). The lowest risk for fibrosis was found with the lowest odds seen in the top quartile of alcohol consumption (aOR 0.23; 95% CI 0.08-0.66; p = .006). Adding soft drink and coffee consumptions, and physical activity to the model did not change the estimates. Subjects with PEth >= 0.3 mu mol/L had higher ORs for a higher fibrosis stage (aOR 2.77; 95% CI 1.01-7.59; p = .047). Conclusion: Lifetime alcohol consumption with up to 13 units per week is associated with lower fibrosis stage in NAFLD. Elevated PEth is associated with higher stages of fibrosis.
|
|
| 5. |
- Immerstrand, Charlotte, 1974-
(författare)
-
Biophysical studies of pigment transport in frog melanophores : impedance measurements and advanced microscopy analyses
- 2003
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Small proteins, other molecules and large organelles are frequently transported from one location to another within cells. These transports employ cytoskeletal networks and enable cells to maintain regions with different functions and attain an asymmetrical shape.The aim of this work was to explore biophysical methods for monitoring intracellular transport processes and associated structural changes. For these studies we have used pigment cells, melanophores, from the African clawed frog Xenopus laevis. In response to external stimuli, these cells can change colour by redistributing pigment granules in the cytoplasm.Transparent "cell clinics" equipped with gold electrodes were developed for impedance studies. The results show that impedance measurements at different frequencies not only can be used to monitor cell attachment and spreading, but also events like pigment aggregation. Significant F-actin breakdown and a cell area decrease may explain the impedance decrease seen during latrunculin-induced aggregation. In aggregation induced by melatonin there was, however, a small increase of the cell area, no F-actin breakdown and still lowered impedance, indicating that some other, likely intracellular mechanism is involved. In addition, confocal laser scanning microscopy (CLSM) studies showed that aggregation was associated with an increase in the cell height, more prominent for latrunculin than for melatonin. This height increase did not seem to involve influx of water through aquaporin channels at the cell membrane, or newly formed or remodelled microtubules in the cells.Besides impedance measurements, Image Correlation Spectroscopy (ICS) was applied to analyse pigment aggregation. The study shows for the first time that ICS can be used to analyse aggregation of non-fluorescent particles and suggests that the method may provide new information on the state of aggregation of granules in pigment cells.
|
|
| 6. |
- Kanno, T, et al.
(författare)
-
Large dense-core vesicle exocytosis in pancreatic beta-cells monitored by capacitance measurements
- 2004
-
Ingår i: Methods. - : Elsevier BV. - 1095-9130 .- 1046-2023. ; 33:4, s. 302-311
-
Tidskriftsartikel (refereegranskat)abstract
- This article discusses the currently used methodologies for monitoring exocytosis as changes in cell capacitance. Details are given on composition of solutions, experimental protocols, and how the observed responses can be interpreted physiologically. The concepts are illustrated by examples from our own work on insulin-releasing pancreatic P-cells. Finally, we consider the feasibility of applying capacitance measurements to endocrine cells in intact pancreatic islets, where the cells are electrically coupled to each other. (C) 2004 Elsevier Inc. All rights reserved.
|
|
| 7. |
|
|
