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- Karlsson, Lars O, 1975, et al.
(författare)
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Constitutive PGC-1α Overexpression in Skeletal Muscle Does Not Contribute to Exercise-Induced Neurogenesis.
- 2021
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Ingår i: Molecular neurobiology. - : Springer Science and Business Media LLC. - 1559-1182 .- 0893-7648. ; 58, s. 1465-1481
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Tidskriftsartikel (refereegranskat)abstract
- Physical exercise can improve age-dependent decline in cognition, which in rodent is partly mediated by restoration of an age-dependent decline in neurogenesis. Exercise-inducible myokines in the circulation present a link in muscle-brain crosstalk. The transcription factor PGC-1α regulates the release of such myokines with neurotrophic properties into the circulation. We study how chronic muscular overexpression of PGC-1α could contribute to exercise-induced effects on hippocampal neurogenesis and if this effect could be enhanced in a running wheel paradigm. We used 3- and 11-month-old transgenic mice with overexpression of PGC-1α under the control of muscle creatinine kinase promoter (MCK-PGC-1α), which have a constitutively developed endurance muscle phenotype. Wild-type and MCK-PGC-1α mice were single housed with free access to running wheels. Four weeks of running in female animals increased the levels of newborn cells, immature neurons, and, for young animals, new mature neurons, compared to sedentary controls. However, no difference in these parameters was observed between wild-type and transgenic mice under sedentary or running conditions. Multiplex analysis of serum cytokines, chemokines, and myokines suggested several differences in serum protein concentrations between genotypes with musclin found to be significantly upregulated 4-fold in male MCK-PGC-1α animals. We conclude that constitutive muscular overexpression of PGC-1α, despite systemic changes and difference in serum composition, does not translate into exercise-induced effects on hippocampal neurogenesis, independent of the age of the animal. This suggests that chronic activation of PGC-1α in skeletal muscle is by itself not sufficient to mimic exercise-induced effects or to prevent decline of neurogenesis in aging.
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| 2. |
- Söfteland, John M., 1977, et al.
(författare)
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Luminal polyethylene-glycol solution delays the onset of preservation injury in the human intestine.
- 2021
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Ingår i: American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons. - : Elsevier BV. - 1600-6143. ; 21:6, s. 2220-2230
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Tidskriftsartikel (refereegranskat)abstract
- The organ damage incurred during the cold storage (CS) of intestinal grafts has short and long-term consequences. Animal studies suggest that additional luminal preservation (LP) with polyethylene-glycol (PEG) may alleviate this damage. This study aims to validate these findings using human intestines. Ileal segments, perfused intravascularly with IGL-1 solution, were procured from 32 multiorgan donors and divided into two parts: one containing a PEG 3350-based solution introduced luminally (LP group) and another one without luminal treatment (control). Sampling was performed after 4h, 8h, 14h, and 24h of CS. Histology was assessed using the Chiu/Park score. Tight junctions (TJ), several inflammatory markers, and transcription factors were examined by immunofluorescence, ddPCR, and Western blot. Tissue water content (edema) was also measured. Apoptotic activity was assessed with caspase 2,3 and 9 assays. LP significantly lowered mucosal injury at all time points. Redistribution of TJ proteins occurred earlier and more severely in the control group. After 24h of CS, LP intestines showed an emerging unfolding protein response. Increased caspase-3 and -9 activity were found in the control group. The current results indicate that luminal PEG is safe and effective in reducing damage to the intestinal epithelium during CS.
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