| 1. |
- Andersson, Lotta E., et al.
(författare)
-
Glutamine-elicited secretion of glucagon-like peptide 1 is governed by an activated glutamate dehydrogenase
- 2018
-
Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 67:3, s. 372-384
-
Tidskriftsartikel (refereegranskat)abstract
- Glucagon-like peptide 1 (GLP-1), secreted from intestinal L cells, glucose dependently stimulates insulin secretion from β-cells. This glucose dependence prevents hypoglycemia, rendering GLP-1 analogs a useful and safe treatment modality in type 2 diabetes. Although the amino acid glutamine is a potent elicitor of GLP-1 secretion, the responsible mechanism remains unclear. We investigated how GLP-1 secretion is metabolically coupled in L cells (GLUTag) and in vivo inmice using the insulin-secreting cell line INS-1 832/13 as reference. A membrane-permeable glutamate analog (dimethylglutamate [DMG]), acting downstream of electrogenic transporters, elicited similar alterations in metabolism as glutamine in both cell lines. Both DMG and glutamine alone elicited GLP-1 secretion in GLUTag cells and in vivo, whereas activation of glutamate dehydrogenase (GDH) was required to stimulate insulin secretion from INS-1 832/13 cells. Pharmacological inhibition in vivo of GDH blocked secretion of GLP-1 in response to DMG. In conclusion, our results suggest that nonelectrogenic nutrient uptake and metabolism play an important role in L cell stimulus-secretion coupling. Metabolism of glutamine and related analogs by GDH in the L cell may explain why GLP-1 secretion, but not that of insulin, is activated by these secretagogues in vivo.
|
|
| 2. |
- Balderas Arroyo, Claudia, et al.
(författare)
-
A randomized trial involving a multifunctional diet reveals systematic lipid remodeling and improvements in cardiometabolic risk factors in middle aged to aged adults
- 2023
-
Ingår i: Frontiers in Nutrition. - 2296-861X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: A multifunctional diet (MFD) combining foods and ingredients with proven functional properties, such as fatty fish and fiber-rich foods, among others, was developed and shown to markedly reduce cardiometabolic risk-associated factors.OBJECTIVE: Here, we aim at examining metabolic physiological changes associated with these improvements.METHODS: Adult overweight individuals without other risk factors were enrolled in an 8-week randomized controlled intervention following a parallel design, with one group ( n = 23) following MFD and one group ( n = 24) adhering to a control diet (CD) that followed the caloric formula (E%) advised by the Nordic Nutritional Recommendations. Plasma metabolites and lipids were profiled by gas chromatography and ultrahigh performance liquid chromatography/mass spectrometry. RESULTS: Weight loss was similar between groups. The MFD and CD resulted in altered levels of 137 and 78 metabolites, respectively. Out of these, 83 were uniquely altered by the MFD and only 24 by the CD. The MFD-elicited alterations in lipid levels depended on carbon number and degree of unsaturation.CONCLUSION: An MFD elicits weight loss-independent systematic lipid remodeling, promoting increased circulating levels of long and highly unsaturated lipids.CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02148653?term=NCT02148653&draw=2&rank=1, NCT02148653.
|
|
| 3. |
- Herzog, Katharina, et al.
(författare)
-
Metabolic Effects of Gastric Bypass Surgery : Is It All About Calories?
- 2020
-
Ingår i: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 69:9, s. 2027-2035
-
Tidskriftsartikel (refereegranskat)abstract
- Bariatric surgery is an efficient method to induce weight loss and also, frequently, remission of type 2 diabetes (T2D). Unpaired studies have shown bariatric surgery and dietary interventions to differentially affect multiple hormonal and metabolic parameters, suggesting that bariatric surgery causes T2D remission at least partially via unique mechanisms. In the current study, plasma metabolite profiling was conducted in patients with (n = 10) and without T2D (n = 9) subjected to Roux-en-Y gastric bypass surgery (RYGB). Mixed-meal tests were conducted at baseline, after the presurgical very-low-calorie diet (VLCD) intervention, immediately after RYGB, and after a 6-week recovery period. Thereby, we could compare fasted and postprandial metabolic consequences of RYGB and VLCD in the same patients. VLCD yielded a pronounced increase in fasting acylcarnitine levels, whereas RYGB, both immediately and after a recovery period, resulted in a smaller but opposite effect. Furthermore, we observed profound changes in lipid metabolism following VLCD but not in response to RYGB. Most changes previously associated with RYGB were found to be consequences of the presurgical dietary intervention. Overall, our results question previous findings of unique metabolic effects of RYGB and suggest that the effect of RYGB on the metabolite profile is mainly attributed to caloric restriction.
|
|
