Elevated urinary Cr loss induces a reduction in renal Cr concentration and the negative Cr balance in streptozotocin-induced diabetic mice.
Chromium (Cr) is an essential trace element and is important for normal carbohydrate metabolism, and its deficiency in animals can cause a diabetic-like state. Human and experimental animal studies suggest that urinary Cr excretion is increased in diabetic populations. To investigate whether hyperglycemia-induced elevation of urinary Cr excretion reduces tissue Cr storage conditions, we assessed total Cr balance and Cr distribution in streptozotocin (STZ)-induced diabetic mice. Male C57BL mice were randomly assigned to STZ or control groups and their urine was collected 7, 14, 21 and 28 d after STZ injection. An inductively coupled plasma mass spectrometry instrument equipped with a dynamic reaction cell was used for determination of Cr in urine, plasma and tissues samples. The urinary excretions of Cr were 15.4+/-3.0 and 356+/-62 ng/d, and the renal Cr concentrations were 0.85+/-0.12 and 0.17+/-0.03 ng/mg for the control and diabetes groups, respectively (p<0.01), after 28 d. The Cr balance in STZ-treated mice was distinctly negative due to the increase in urinary Cr loss (p<0.01). These results suggest that in mice, STZ induces a reduction in renal Cr concentration and total negative Cr balance caused by an increase in urinary Cr output.
Mita
Yukiko
Y
Department of Human Nutrition, School of Life Studies, Sugiyama Jogakuen University, Nagoya, Aichi 464-8662, Japan. yukiko@sugiyama-u.ac.jp
Ishihara
Kengo
K
Ishiguro
Megumi
M
Takeda
Masako
M
Hattori
Reiko
R
Murakami
Kurumi
K
Yamada
Ayumi
A
Yasumoto
Kyoden
K
D000419:Albuminuria / Q000378:metabolism; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002857:Chromium / Q000652:urine*; D003404:Creatinine / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D003928:Diabetic Nephropathies / Q000378:metabolism*; D004435:Eating; D006943:Hyperglycemia / Q000378:metabolism; D007328:Insulin / Q000097:blood; D007408:Intestinal Absorption / Q000502:physiology; D007668:Kidney / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009929:Organ Size
D001786:Blood Glucose; D007328:Insulin; D002857:Chromium; D003404:Creatinine