Long-Term Exposure to [Cr3O(O2CCH2CH3)6(H2O)3]+ in Wistar Rats Fed Normal or High-Fat Diets Does Not Alter Glucose Metabolism

Inadequate iron supply has significant consequences to health. There are some relations between the metabolism of different trace elements, such as iron, zinc, copper and chromium. However, the direction of these interactions can be antagonistic or synergistic, and it depends on many factors. The aim of the study was to evaluate the combined effects of supplementary of chromium(III) propionate complex (Cr3) with iron excess on the Cr and Fe status in healthy female rats. The 36 healthy female Wistar rats were divided into six experimental groups (six animals in each) with different Fe levels—adequate (45 mg kg−1—100% RDA) and high (excessive—180 mg kg−1—400% RDA). At the same time, they were supplemented with Cr(III) at doses of 1, 50 and 500 mg kg−1 of diet: C1—control (Fe 45 mg kg−1, Cr 1 mg kg−1); C50 (Fe 45 mg kg−1, Cr 50 mg kg−1); C500 (Fe 45 mg kg−1, Cr 500 mg kg−1); H1 (Fe 180 mg kg−1, Cr 1 mg kg−1); H50 (Fe 180 mg kg−1, Cr 50 mg kg−1); H500 (Fe 180 mg kg−1, Cr 500 mg kg−1). The serum iron level and total iron binding capacity (TIBC) were measured with colorimetric methods. The serum ferritin level was measured by means of electrochemiluminescence immunoassay. The serum transferrin level was measured with the ELISA method. Haematological measurements were made with an automated blood analyser. The Cr and Fe tissular levels were measured with the AAS method. The exposure to a high level of Fe(III) alone or in combination with Cr caused Fe accumulation in tissues, especially in the liver and kidneys, but there were no significant changes in the TIBC, transferrin, ferritin concentration in the serum and most haematological parameters. Moreover, the serum, hepatic and renal Cr concentrations decreased. The doses of supplementary Cr(III) given separately or in combination with high level of Fe(III) disturbed the Cr content in the liver and kidneys of healthy female rats. However, they did not change most of the parameters of Fe metabolism, except the Fe kidney concentration. Supplementary Cr3 decreased the renal Fe level in groups with adequate Fe content in the diet. However, the renal Fe levels increased along with a higher Cr level in the diet in groups with high Fe content. The findings proved a relationship between Fe(III) and Cr(III) metabolism in healthy female rats. However, the direction of change varied and depended on relative amounts of these elements in the diet.

Section: Discussionmentioning

confidence: 98%

The Combined Effects of Iron Excess in the Diet and Chromium(III) Supplementation on the Iron and Chromium Status in Female Rats

Staniek

Wójciak

2017

“…Some reports have shown that chromium(III) has beneficial effects for the organism with disturbances of glucose and lipid metabolism [ 4 , 17 , 31 ]. However, data from the experiments conducted in healthy individuals quite often explicitly show lack of any favourable impact of Cr(III) on carbohydrates/lipid metabolism [ 27 , 32 – 34 ]. Our study [ 27 ] showed no effect of Cr3 at doses 100–1000 mg of Cr(III)· kg −1 diet on serum glucose, total cholesterol, LDL-cholesterol, and HDL-cholesterol concentration (Table 4 ).…”

Section: Discussionmentioning

confidence: 99%

“…Healthy Sprague-Dawley rats treated daily with 20 μg· kg −1 body mass as Cr3 intravenously for 12 weeks had lower blood plasma insulin, total cholesterol, LDL, HDL and triglycerides but not glucose levels [ 31 ]. The data obtained by Herring et al [ 32 ] strongly suggest that long-term (15-month) Cr3 supplementation does not significantly affect metabolic responses in blood glucose concentration to glucose and insulin in male Wistar rats consuming a normal diet or high-fat, high-carbohydrate cafeteria-style diet. Also Król et al [ 33 ] confirmed that supplementary Cr3, given in the dosages 0.6 and 3 mg· kg −1 b.m.…”

Section: Discussionmentioning

confidence: 99%

The Effects of Supplementary Cr3 (Chromium(III) Propionate Complex) on the Mineral Status in Healthy Female Rats

Staniek

Krejpcio

2017

More and more people use food supplements for various reasons, e.g. to prevent mineral deficiency and diseases (e.g. osteoporosis, diabetes, anaemia). Supplements containing Cr(III) are purchased primarily for weight loss and antidiabetic effects. The aim of this study was to evaluate the effects of supplementary Cr3 {chromium(III) propionate complex, [Cr3O(O2CCH2CH3)6(H2O)3]NO3)} on the mineral status in female Wistar rats. The study was carried out on 30 female Wistar rats, divided into five groups (six animals in each): a control group and test groups fed Cr3 supplemented diets with 100, 200, 500 and 1000 mg Cr · kg−1 diet (equivalent to 10, 20, 50 and 100 mg Cr ·kg−1 body mass (b.m.) per day) given as Cr3 for 4 weeks. Supplementary Cr3 increased the Cr content in tissues in a dose-dependent manner. High dietary doses of Cr3, 20 and 100 mg Cr · kg−1 b.m., increased the Cu content in the liver and spleen as well as the Zn content in the kidneys but decreased the liver Ca content. Doses of 50–100 mg Cr ·kg−1 b.m. decreased the serum Fe concentration and the Fe content in the liver and kidneys. Supplementation with Cr3 at doses of 10 and 100 mg Cr ·kg−1 b.m. did not affect the Mg content in the rats’ tissues. In conclusion, high dietary doses of Cr3 (10 and 100 mg Cr· kg−1 b.m.) given for 4 weeks affected the mineral status of Fe, Zn, Cu and Ca in the tissues of healthy female Wistar rats.

“…This statement falls in agreement with the observations that supplementary Cr, no matter what chemical form or dosage is applied, has no effect on a healthy organism, both in animals and humans. Recently, Herring et al [ 48 ] studied the same Cr compound (Cr3 or CrProp) in healthy rats fed cafeteria-style diets (high-fat and high-carbohydrate diets) in a long exposure experiment. After a 15-month feeding of rats using those diets, CrProp at a dosage of 1 mg/kg b.m./day had no effect on body mass, organ masses (liver, kidneys, lungs, and heart), or visceral fat mass.…”

Section: Discussionmentioning

confidence: 99%

Supplementary Chromium(III) Propionate Complex Does Not Protect Against Insulin Resistance in High-Fat-Fed Rats

Król

Krejpcio

Iwanik

2014

Improper eating habits such as high-fat or high-carbohydrate diets are responsible for metabolic changes resulting in impaired glucose tolerance, hyperinsulinemia, insulin resistance, and ultimately diabetes. Although the essentiality of trivalent chromium for humans has been recently questioned by researchers, pharmacological dosages of this element can improve insulin sensitivity in experimental animals and diabetic subjects. The aim of the study was to assess the preventive potential of the supplementary chromium(III) propionate complex (CrProp) in rats fed a high-fat diet. The experiment was conducted on 32 male Wistar rats divided into four groups and fed the following diets: the control (C, AIN-93G), high-fat diets (HF, 40 % energy from fat), and a high-fat diet supplemented with CrProp at dosages of 10 and 50 mg Cr/kg diet (HF + Cr10 and HF + Cr50, respectively). After 8 weeks, high-fat feeding led to an increased body mass, hyperinsulinemia, insulin resistance, a decreased serum urea concentration, accumulation of lipid droplets in hepatocytes, and increased renal Fe and splenic Cu contents. Supplementary CrProp in both dosages did not alleviate these changes but increased renal Cr content and normalized splenic Cu content in high-fat-fed rats. Supplementary CrProp does not prevent the development of insulin resistance in rats fed a high-fat diet.