| 1. |
|
|
| 2. |
|
|
| 3. |
- Göktürk, Camilla, et al.
(författare)
-
Semicarbazide-sensitive amine oxidase in transgenic mice with diabetes
- 2004
-
Ingår i: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier BV. - 0006-291X .- 1090-2104. ; 325:3, s. 1013-1020
-
Tidskriftsartikel (refereegranskat)abstract
- Semicarbazide-sensitive amine oxidase (SSAO) activity in plasma is increased in diabetes, and in particular, in diabetic patients with vascular complications. It has been speculated that SSAO is involved in the development of such complications due to the production of cytotoxic compounds. In this work, we have induced diabetes in a previously described mouse-model, overexpressing SSAO in smooth muscle cells. SSAO activity was estimated as well as expression of the endogenous mouse gene and human transgene using real-time PCR. Diabetes induced an increase in SSAO activity in serum, kidney, and adipose tissue of transgenic animals. An inverse correlation between SSAO activity and mouse SSAO mRNA levels was observed in transgenic animals with diabetes. These results further support the suggestion of a negative feedback control of the SSAO gene expression. The increased SSAO activity in diabetes is most likely dependent on post-transcriptional modifications or activation of existing inactive enzyme molecules.
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Nordquist, Jenny
(författare)
-
Semicarbazide-sensitive amine oxidase and vascular complications in diabetes mellitus : Biochemical and molecular aspects
- 2002
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Plasma activity of the enzyme semicarbazide-sensitive amine oxidase (SSAO; EC.1.4.3.6) has been reported to be high in disorders such as diabetes mellitus, chronic congestive heart failure and liver cirrhosis. Little is known of how the activity is regulated and, consequently, the cause for these findings is not well understood. Due to the early occurrence of increased enzyme activity in diabetes, in conjunction with the production of highly cytotoxic substances in SSAO-catalysed reactions, it has been speculated that there could be a causal relationship between high SSAO activity and vascular damage. Aminoacetone and methylamine are the best currently known endogenous substrates for human SSAO and the resulting aldehyde-products are methylglyoxal and formaldehyde, respectively. Both of these aldehydes have been shown to be implicated in the formation of advanced glycation end products (AGEs).This thesis is based on studies exploring the regulation of SSAO activity and its possible involvement in the development of vascular damage. The results further strengthen the connection between high SSAO activity and the occurrence of vascular damage, since type 2 diabetic patients with retinopathy were found to have higher plasma activities of SSAO and lower urinary concentrations of methylamine than patients with uncomplicated diabetes. From studies on mice, it was also found that an SSAO inhibitor potently reduces the incorporation of methylamine-metabolite in the tissues. By quantifying SSAO-gene expression in alloxan-induced diabetes, increased transcription could be ruled out as a cause for the increased enzyme activity, thereby opening up for the possibility that the activity is regulated post-translationally. In fact, increased enzyme activity in adipose tissue was accompanied by decreased mRNA-levels, suggesting that the gene expression could be negatively controlled by the enzyme activity.
|
|
| 8. |
|
|
| 9. |
|
|
| 10. |
- Nordquist, Jenny, et al.
(författare)
-
Transcription factors in muscle atrophy caused by blocked neuromuscular transmission and muscle unloading in rats
- 2007
-
Ingår i: Molecular Medicine. - 1076-1551 .- 1528-3658. ; 13:9-10, s. 461-470
-
Tidskriftsartikel (refereegranskat)abstract
- The muscle wasting associated with long-term intensive care unit (ICU) treatment has a negative effect on muscle function resulting in prolonged periods of rehabilitation and a decreased quality of life. To identify mechanisms behind this form of muscle wasting, we have used a rat model designed to mimic the conditions in an ICU. Rats were pharmacologically paralyzed with a postsynaptic blocker of neuromuscular transmission, and mechanically ventilated for one to two weeks, thereby unloading the limb muscles. Transcription factors were analyzed for cellular localization and nuclear concentration in the fast-twitch muscle extensor digitorum longus (EDL) and in the slow-twitch soleus. Significant muscle wasting and upregulation of mRNA for the ubiquitin ligases MAFbx and MuRF1 followed the treatment. The IκB family–member Bcl-3 displayed a concomitant decrease in concentration, suggesting altered κB controlled gene expression, although NFκB p65 was not significantly affected. The nuclear levels of the glucocorticoid receptor (GR) and the thyroid receptor α1 (TRα1) were altered and also suggested as potential mediators of the MAFbx- and MuRF1-induction in the absence of induced Foxo1. We believe that this model, and the strategy of quantifying nuclear proteins, will provide a valuable tool for further, more detailed, analyses of the muscle wasting occurring in patients kept on a mechanical ventilator.
|
|
