SUMMARY Growth differentiation factor 11 (GDF11), a TGF-beta super-family member, is highly homologous to myostatin and essential for embryonic patterning and organogenesis. Reports of GDF11 effects on adult tissues are conflicting, with some describing anti-aging and pro-regenerative activities on the heart and skeletal muscle while others opposite or no effects. Herein, we sought to determine the in vivo cardiac and skeletal muscle effects of excess GDF11. Mice were injected with GDF11 secreting cells, an identical model to that used to initially identify the in vivo effects of myostatin. GDF11 exposure in mice induced whole body wasting and profound loss of function in cardiac and skeletal muscle over a 14-day period. Loss of cardiac mass preceded skeletal muscle loss. Cardiac histologic and echocardiographic evaluation demonstrated loss of ventricular muscle wall thickness, decreased cardiomyocyte size and decreased cardiac function 10 days following initiation of GDF11 exposure. Changes in skeletal muscle after GDF11 exposure were manifest at day 13 and associated with wasting, decreased fiber size, and reduced strength. Changes in cardiomyocytes and skeletal muscle fibers were associated with activation of SMAD2, the ubiquitin-proteasome pathway and autophagy. GDF11 over administration in vivo results in cardiac and skeletal muscle loss, dysfunction and death. Serum levels of GDF11 by Western blotting were 1.5 fold increased over controls. Although GDF11 effects in vivo are likely dose, route, and duration dependent, its physiologic changes are similar to myostatin and other Activin receptors ligands. These data support that GDF11, like its other closely related TGF-beta family members, induces loss of cardiac and skeletal muscle mass and function.
Aims Repair of abdominal aortic aneurysms (AAA) decreases the incidence of rupture and death. In cancer patients, sarcopenia has been associated with increased surgical complications and mortality. The impact of sarcopenia on survival after AAA repair has yet to be described. Methods and ResultsPatient demographic, laboratory, body composition measurements and survival data were obtained from patients undergoing AAA repair at the Indiana University medical campus over a 5-year period. Univariate and multivariate analyses were performed to identify factors associated with overall survival. Overall, 58.2% presented with sarcopenia. Sarcopenic patients were older (71.88.3 versus 66.88.1 years; p<0.001), had lower body mass index (BMI) (26.35.2 versus 31.55.9 kg/m 2 ; p<0.001), higher rates of myosteatosis (84.4% versus 52.%; p<0.001), greater AAA diameter (60.614.0 versus 57.811.7 mm; p=0.016), higher Charlson Comorbidity Index (CCI) (32.3% versus 25.1% 6; p=0.034), and increased rates of rupture (8.2% versus 3.8%; p=0.047). Sarcopenic and nonsarcopenic patients had no difference in 30-day morbidity (8.5% versus 8.5%; p=0.991) or mortality (3.7% versus 0.9%; p=0.07). Univariate analysis demonstrated age, sarcopenia, myosteatosis, CCI, and BMI to be associated with long-term survival. There was no correlation between BMI and sarcopenia. Both sarcopenia and myosteatosis resulted in decreased one-, three-, and five-year survivals compared to their counterparts. On multivariate analysis sarcopenia is independently associated with survival, conferring a 1.6-fold increase in death (p=0.04). The combination of sarcopenia plus myosteatosis doubled the risk of death compared to sarcopenia alone.Conclusions This is the first study to demonstrate that over half of all patients undergoing AAA repair are sarcopenic, a condition associated with increased mortality. Sarcopenia with myosteatosis is associated with double the mortality of sarcopenia alone. CT scan, but not BMI, accurately identifies sarcopenia and myosteatosis. Defining the mechanisms through which sarcopenia contributes to late death after AAA repair is critical to developing novel interventions that may improve survival in this high risk population.
ABMNC therapy provides long-term freedom from AFS, major amputation, and MALE that are comparable with other reports of patients who underwent surgical and endovascular interventions for CLI. Furthermore, no patients developed tumorigenesis or clinically significant retinopathy. Because of the limited number of patients studied, our findings will need to be followed up in a larger phase III trial.
MI was accompanied by ERS, probably involving the MAPK signaling pathway. SB203580, a specific inhibitor of this pathway, can relieve cardiomyocyte apoptosis and protect the myocardium by suppressing such stress (Tab. 3, Fig. 7, Ref. 20).
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