Aortic stiffness in diabetes mellitus--association with glutamine and heat shock protein 70 expression: a pilot study based on an experimental rodent model.
BACKGROUND
Diabetes mellitus (DM) alters arterial wall compliance and causes aortic stiffness, which is a predictor of vascular mortality. Heat shock proteins (HSPs) are involved in the protection of cells under stress. We evaluated aortic stiffness in DM and the effects of glutamine (which induces HSP 70) on HSP 70 levels in experimental DM.


METHODS
Male Sprague-Dawley rats (n = 30) were divided into three groups: Control (Group 1), DM (Group 2) and glutamine-treated DM (Group 3). DM was induced using streptozocin injection. Group 3 rats received two doses of glutamine during the fourth week. Blood and infrarenal aortic tissue samples were obtained for analysis at the end of the fourth week.


RESULTS
Compared with Group 1, serum HSP 70 levels were significantly increased in Groups 2 and 3. Aortic HSP 70 was increased in DM. There was a significant difference in aortic HSP 70 with glutamine injection (Group 1 versus Group 3). DM also interfered with the elastin content of the aorta. There was a significant correlation between the serum glucose and serum and aortic HSP 70 levels and between serum and aortic HSP 70 levels; as well as between severity of DM and aortic elastin levels.


CONCLUSIONS
DM causes aortic stiffness and this may contribute to the increase in mortality and morbidity associated with DM. The expression of HSP 70 may become a therapeutic target.
Ugurlucan
Murat
M
Istanbul University Istanbul Medical Faculty, Department of Cardiovascular Surgery, Atasehir, Zumrut Sitesi, Blok: 9, Daire: 9, 81120 Atasehir/Istanbul, Turkey.
Erer
Dilek
D
Kalko
Yusuf
Y
Gungor
Funda
F
Haholu
Aptullah
A
Basaran
Murat
M
Banach
Maciej
M
Rysz
Jacek
J
Mikhailidis
Dimitri P
DP
Tireli
Emin
E
Dayioglu
Enver
E
Alpagut
Ufuk
U
D000818:Animals; D001011:Aorta / Q000503:physiopathology*; D001786:Blood Glucose / Q000378:metabolism; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology*; D004549:Elastin / Q000378:metabolism; D005786:Gene Expression Regulation; D005973:Glutamine / Q000494:pharmacology; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D010865:Pilot Projects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012720:Severity of Illness Index; D013311:Streptozocin
D001786:Blood Glucose; D018840:HSP70 Heat-Shock Proteins; D005973:Glutamine; D013311:Streptozocin; D004549:Elastin