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PubMed2002

Optimal dietary concentration of chromium for alleviating the effect of heat stress on growth, carcass qualities, and some serum metabolites of broiler chickens.

This study was conducted to determine the effects of chromium (chromium picolinate, CrPic) supplementation at various levels (0, 200, 400, 800, or 1200 microg/kg of diet) on performance, carcass characteristics, and some serum metabolites of broiler chickens (Ross) reared under heat stress (32.8 degrees C). One hundred fifty old male broilers were randomly assigned to 5 treatment groups, 3 replicates of 10 birds each. The birds were fed either a control diet or the control diet supplemented with either 200, 400, 800, or 1200 microg Cr/kg of diet. Increased supplemental chromium resulted in an increase in body weight (p = 0.01, linear), feed intake (p < or = 0.05, linear), and carcass characteristics (p < or = 0.05, linear) and improved feed efficiency (p = 0.01, linear). Increased supplemental chromium decreased serum corticosterone concentration (p = 0.01, linear), whereas it increased serum insulin and T3 and T4 concentrations (p = 0.01). Serum glucose and cholesterol concentrations decreased (p = 0.01), whereas protein concentrations increased linearly (p = 0.001) with higher dietary chromium supplementation. Results of the present study conclude that a supplementation of diet with chromium at 1200 ppb can alleviate the detrimental effects of heat stress in broiler.

Animals↗
PubMed1987

Separation of biologically active chromium complex from cow colostrum.

By a procedure based on ion-exchange chromatography, five chromium-containing fractions were separated from the ethanol extract (50-90%) of cows' colostrum which should provide infant with all or most of the chromium needed in available form. Three of the fractions are anionic (A-1, A-2 and A-3) and two are cationic (C-1 and C-2). Two major fractions, A-1 and A-3, comprise together about 77% of the total chromium recovered in the effluent after ion-exchange chromatography and C-1 and C-2 comprise together only about 21%. Approximate molecular weight was determined by the Sephadex gel chromatography to be 1,500 for A-1 and C-2 and 2,000 for C-1. A-3 was eluted from the Sephadex gel column at the elution position corresponding to that of inorganic trivalent chromium. Among five fractions, A-1 shows glucose tolerance factor (GTF) activity as measured by the stimulation of [U-14C] glucose oxidation to 14CO2 in rat epididymal adipocytes. A-1 stimulates glucose oxidation at chromium concentration as low as 100 pg/ml only when it is incubated with insulin. These findings suggest that A-1 fraction separated from cow milk contains a low-molecular-weight, chromium complex which plays a role in glucose metabolism in close relation with the action of insulin.

Adipose Tissue↗
PubMed2005

Comparison of polyethylene wear associated with cobalt-chromium and zirconia heads after total hip replacement. A prospective, randomized study.

BACKGROUND: A ceramic femoral head is an alternative to a metal femoral head for the bearing surface of total hip arthroplasty. The purpose of this study was to compare polyethylene wear in patients who had undergone bilateral total hip arthroplasty with implants that differed only with regard to the material used for the femoral head: a zirconia head was used on one side, and a cobalt-chromium head was inserted on the contralateral side. METHODS: A prospective, randomized study was performed to evaluate the outcomes in fifty-two patients who had undergone sequential bilateral primary total hip replacement. A zirconia head was used in one hip, and a cobalt-chromium head was used in the other. There were forty-eight men and four women; the mean age at the time of surgery was 44.2 years. The mean duration of follow-up was 7.1 years. Clinical and radiographic evaluations were performed preoperatively and at six weeks; three, six, and twelve months; and yearly postoperatively. Linear wear of the polyethylene liner was measured radiographically. Two femoral components with a zirconia head had aseptic loosening and were revised. The explanted heads were evaluated with use of interferometry, environmental scanning electron microscopy, and x-ray diffraction studies. RESULTS: The mean polyethylene wear rate was 0.08 mm/yr in association with the zirconia heads and 0.17 mm/yr in association with the cobalt-chromium heads (p = 0.004). The mean amount of volumetric polyethylene wear was 350.8 mm3 in association with the zirconia heads and 744.7 mm3 in association with the cobalt-chromium heads (p = 0.004). With regard to surface roughness, the Ra values of the two explanted zirconia heads were 15.87 and 17.35 nm and the Rpm values were 153.86 and 156.18 nm. Two identical zirconia heads that had not been implanted had Ra values of 5.31 and 5.48 nm and Rpm values of 65.27 and 66.35 nm. Four unimplanted cobalt-chromium heads that were identical to the ones implanted in this study had Ra values ranging between 25 and 50 nm and Rpm values ranging between 262.6 and 525.2 nm. Little phase transformation was noted in the two revised zirconia heads. CONCLUSIONS: The mean amount and rate of polyethylene wear were significantly lower in the hips with a zirconia head than they were in the hips with a cobalt-chromium head, presumably because the zirconia heads had a smoother articulating surface.

Adult↗
PubMed1982

Effect of exercise (running) on serum glucose, insulin, glucagon, and chromium excretion.

Chromium is involved in normal glucose metabolism. To test whether chromium is also associated with the exercise-induced increases in glucose utilization, urinary chromium excretion, serum glucose, insulin, and glucagon of nine male runners (23-46 yr) were evaluated. Blood samples were taken prior to, immediately following, and 2 h after a strenuous 6-mile run. Urine samples were also taken at these times, and total daily urine collections were made the day of the run and the following day. Mean serum glucose for all runners immediately after running was 185 +/- 19 mg/dl compared with 90 +/- 1 mg/dl (mean +/- SE) prior to running. Mean serum glucagon immediately after running was significantly elevated compared with that observed prior to or 2 h after running; serum insulin levels were not altered significantly. Mean urinary chromium concentration was increased nearly five-fold 2 h after running; similar results were obtained when chromium concentration was expressed per mg of creatinine. Total daily urinary Cr excretion was approximately two times higher the day of running compared with the following nonrun day. Daily urinary excretion of sodium, potassium, and calcium were measured to determine if exercise had a general nonspecific effect on renal function; daily urinary excretion of these was not changed by exercise. These data demonstrate that accompanying the exercise-induced changes associated with increased glucose utilization, there is a significant increase in chromium excretion.

Adult↗
PubMed2004

Lower toenail chromium in men with diabetes and cardiovascular disease compared with healthy men.

OBJECTIVE: Chromium may improve insulin sensitivity, which can modify the risk of diabetes and cardiovascular disease (CVD). Therefore, we evaluated the association between toenail chromium and CVD in diabetic men. RESEARCH DESIGN AND METHODS: We performed cross-sectional and nested case-control analyses among men aged 40-75 years within the Health Professionals Follow-up Study. The cross-sectional analysis compared men with diabetes only (n = 688), diabetes with prevalent CVD (n = 198), and healthy control subjects (n = 361). The nested case-control study included 202 men with baseline diabetes who developed incident CVD and 361 matched control subjects. RESULTS: Mean toenail chromium (microg/g) was 0.71 in healthy control subjects, 0.61 in diabetes-only subjects, and 0.52 in diabetic subjects with prevalent CVD (P for trend = 0.003). In the cross-sectional analysis, the multivariate odds ratio (OR) between extreme quartiles was 0.74 (95% CI 0.49-1.11; P for trend = 0.18), comparing diabetes only with healthy control subjects. A similar comparison between diabetic subjects with prevalent CVD and healthy control subjects yielded an OR of 0.45 (0.24-0.84; P for trend = 0.003). In the nested case-control study, comparing diabetic men with incident CVD with healthy control subjects, the multivariate OR was 0.65 (0.36-1.17; P for trend = 0.16) between extreme quartiles. When we combined prevalent and incident CVD cases among diabetic men and compared them with healthy control subjects, the OR was 0.62 (0.39-1.01; P for trend = 0.02) between extreme quartiles. CONCLUSIONS: Our results suggest that diabetic men with CVD have lower toenail chromium than healthy control subjects. However, this study could not distinguish between the effects of chromium on diabetes and those on CVD. Long-term clinical trials are needed to determine whether chromium supplementation is beneficial for preventing CVD among diabetic patients.

Adult↗
PubMed2006

Chromium treatment has no effect in patients with poorly controlled, insulin-treated type 2 diabetes in an obese Western population: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: Chromium treatment has been reported to improve glycemic control and insulin sensitivity in specific populations of patients with type 2 diabetes. The aim of this study was to determine the effect of chromium treatment on glycemic control in a Western population of insulin-dependent patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: In this 6-month double-blind study, patients with an HbA(1c) (A1C) >8% and insulin requirements of >50 units/day were randomly assigned to receive treatment with placebo or 500 or 1,000 mug chromium daily in the form of chromium picolinate. The primary efficacy parameter was a change in A1C. Secondary end points were changes in lipid profile, BMI, blood pressure, and insulin requirements. RESULTS: In this per-protocol analysis (n = 46), the decrease in A1C was approximately equal across the three groups (0.4%). All patients had a BMI >25 kg/m(2). No differences were found in the secondary end points. We found a weak relationship between an increasing serum chromium concentration and improvement of the lipid profile. CONCLUSIONS: There is no evidence that high-dose chromium treatment is effective in obese Western patients with type 2 diabetes.

Aged↗
PubMed2000

Effect of dietary chromium-L-methionine on glucose metabolism of beef steers.

Thirty-six crossbred steers (288 +/- 3.7 kg initial BW) were used to determine the effect of Cr, as chromium-L-methionine, on glucose tolerance and insulin sensitivity in beef calves. Calves were fed a control diet or the diet supplemented with 400 or 800 microg Cr/kg of diet as chromium-L-methionine. Calves were kept in drylots (six calves/pen; two pens/dietary treatment). Steers were caught twice a day in locking headgates and individually fed their respective diets for a period of 22, 23, or 24 d prior to the metabolic challenges. Calves received a totally mixed diet containing 54% corn, 38% cottonseed hulls, and 5% soybean meal. On d 21, 22, and 23, four calves/dietary treatment were fitted with an indwelling jugular catheter. Approximately 24 h after catheterization, an intravenous glucose tolerance test (500 mg glucose/kg of BW), followed 5 h later by an intravenous insulin challenge test (0.1 IU insulin/kg of BW), was conducted. There was no effect (P > 0.10) of dietary treatment on ADG or ADFI. During the intravenous glucose tolerance test, serum insulin concentrations were increased by supplemental chromium-L-methionine (linear effect of Cr, P < 0.05). There was a time x treatment interaction (P < 0.05) on plasma glucose concentrations after the glucose infusion. Plasma glucose concentrations of calves fed 400 microg Cr/kg of diet were lower than those of controls and calves supplemented with 800 microg Cr/kg of diet (quadratic effect of Cr, P < 0.05) 5 and 10 min after the glucose infusion. Supplemental chromium-L-methionine increased the glucose clearance rate from 5 to 10 min after the insulin challenge test (linear effect of Cr, P < 0.05). Glucose half-life from 5 to 10 min after the insulin infusion was also decreased by supplemental chromium-L-methionine (linear effect of Cr, P < 0.10). These data indicate that supplemental Cr, as chromium-L-methionine, increased glucose clearance rate after an insulin infusion and increased the insulin response to an intravenous glucose challenge in growing calves with functioning rumens.

Animal Feed↗
PubMed2004

Effect of hexavalent carcinogenic chromium on carp Cyprinus carpio immune cells.

Chromium is widely used in industrial processes, and is released into aquatic environments by electroplating, tannery and textile industries. Fishes in natural waters or in aquaculture facilities supplied with these waters are exposed to chromium waste and are presumed to be affected by deposits. Herein, we examine the effect of hexavalent chromium on carp Cyprinus carpio derived immune cells. In vitro exposure of carp leukocytes to hexavalent chromium induced cytotoxicity, decreased mitogen-induced lymphocyte activation and phagocyte functions at concentrations between 2 and 200 micromol Cr l(-1). Neutrophils responded to chromium challenge by changes in cell shape together with reduced nitric oxide and reactive oxygen production. This occurred at much lower concentrations than for the cytotoxic effects seen in leukocyte cultures derived from peripheral blood or pronephros. In a similar way, activation of carp lymphocytes by pokeweed mitogen was reduced in a dose-dependent manner, while cytotoxic effects on non-activated lymphocytes were observed at much higher doses of 200 micromol Cr l(-1). Altered lymphocyte and neutrophil functions are considered to be responsible for decreased resistance to pathogens observed in fishes under chronic chromium challenge.

Analysis of Variance↗
PubMed2003

Hair chromium concentration of northern Finns.

OBJECTIVES: The present study is a pilot project for the Finnish AMAP (Arctic Monitoring and Assessment Programme/Human Health) investigations. We examined the exposure of northern Finns to chromium (Cr), because analyses of this metal are not included in the AMAP, and local industry and industry throughout the Kola Peninsula may increase chromium fallout in Finnish Lapland. Chromium exposure and its temporal trend were estimated by analyzing hair of northern Finns collected in 1982 and 1991. METHODS: After washing the hair samples, chromium analyses were carried out in 1995 by a method developed by Salmela et al. (1981) and Kumpulainen et al. (1982). The Perkin-Elmer 5000 atomic absorption spectrometer used was equipped with a graphite furnace (HGA-400). RESULTS: Age showed no statistically significant correlation with Cr concentration in hair, but the hair concentration of Cr in men was higher than that in women, both among southern and northern Finns and Sami. CONCLUSIONS: Chromium levels in the hair of Finns and Sami were too low to result in any health hazard, however, exposure to chromium may have slightly increased during the 1990s.

Air Pollutants↗
PubMed1999

Chromium potentiation of antidepressant pharmacotherapy for dysthymic disorder in 5 patients.

BACKGROUND: Dysthymic disorder is a relatively common illness that is often treated with antidepressants. Compared with the study of major depression, there has been little systematic study of potentiation strategies for antidepressant-refractory dysthymic disorder. METHOD: Following a patient's report of dramatic response to the addition of chromium supplementation to sertraline pharmacotherapy for dysthymic disorder (DSM-IV), the authors initiated a series of single-blind and open-label trials of chromium picolinate or chromium polynicotinate in the treatment of antidepressant-refractory dysthymic disorder. RESULTS: In a series of 5 patients, chromium supplementation led to remission of dysthymic symptoms. Single-blind substitution of other dietary supplements in each of the patients demonstrated specificity of response to chromium supplementation. CONCLUSION: Preliminary observations suggest that chromium may potentiate antidepressant pharmacotherapy for dysthymic disorder. Controlled studies are indicated to test the validity of these initial observations.

Adult↗
PubMed1987

Mortality in two cohorts of welders exposed to high- and low-levels of hexavalent chromium.

Hexavalent chromium particles are generated in the welding of stainless steel. These particles have manifested a mutagenic action in bacterial test systems and produced chromosome aberrations in cultured Chinese hamster cells. A cohort consisting of 234 welders working on stainless steel and exposed to high levels of chromium was selected. According to an earlier survey the hexavalent chromium exposure of such welders was often above 20 micrograms/m3. Another cohort consisting of 208 railway track welders exposed to low levels of chromium was also selected. The participants of both cohorts had welded for at least five years some time between 1950 and 1965 and were followed for mortality until December 1984. Among the welders exposed to high chromium levels five deaths occurred due to pulmonary tumors. This number is significantly greater than the one death that occurred among the welders exposed to low levels of chromium, but not significantly greater than the corresponding mortality of the general population. Thus exposure to stainless steel welding fumes might be associated with an increased incidence of pulmonary tumors.

Chromium↗
PubMed1979

Chromium deficiency during total parenteral nutrition.

Chromium is required for maintenance of normal glucose tolerance. After complete bowel resection and five months of total parenteral nutrition, severe glucose intolerance, weight loss, and a metabolic encephalopathy-like confusional state developed in a patient. Serum chromium levels were at the lowest normal level. Supplementation of 150 microgram of chromium per day reversed the glucose intolerance, reduced insulin requirements, and resulted in weight gain and the disappearance of encephalopathy. The low levels of chromium and response to chromium supplementation suggest that chromium deficiency can arise in long-term total parenteral nutrition.

Blood Glucose↗
PubMed2000

The effects of inorganic chromium and brewer's yeast supplementation on glucose tolerance, serum lipids and drug dosage in individuals with type 2 diabetes.

OBJECTIVE: To study the effects of supplementation with organic and inorganic chromium on glucose tolerance, serum lipids, and drug dosage in type 2 diabetes patients, in the hope of finding a better and more economical method of control. METHODS: Seventy eight type 2 diabetes patients were divided randomly into two groups and given Brewer's yeast (23.3ug Cr/day), and CrCl3 (200ug Cr/day) sequentially with placebo in between, in a double blind cross-over design of four stages, each lasting 8 weeks. At the beginning and end of each stage, subjects were weighed, their dietary data and drug dosage recorded, and blood and urine samples were collected for analysis of glucose (fasting and 2 hour post 75g glucose load) fructosamine, triglycerides, total and HDL-cholesterol, and serum and urinary chromium. RESULTS: Both supplements caused a significant decrease in the means of glucose (fasting and 2 hour post glucose load), fructosamine and triglycerides. The means of HDL-cholesterol, and serum and urinary chromium were all increased. The mean drug dosage decreased slightly (and significantly in case of Glibenclamide) after both supplements and some patients no longer required insulin. No change was noted in dietary intakes or Body Mass Index. A higher percentage of subjects responded positively to Brewer's yeast chromium, which was retained more by the body, with effects on fructosamine, triglycerides, and HDL-cholesterol maintained in some subjects when placebo followed it, and mean urinary chromium remaining significantly higher than zero time mean. CONCLUSION: Chromium supplementation gives better control of glucose and lipid variables while decreasing drug dosage in type 2 diabetes patients. A larger scale study is needed to help decide on the convenient chemical form, and dosage required to achieve optimal response.

Adult↗
PubMed2002

Demographic responses of the polychaete Dinophilus gyrociliatus to chromium exposure.

The effects of chromium on the life history and demography of Dinophilus gyrociliatus (Polychaeta) were studied on a control and three treated cohorts kept in artificial seawater enriched with nominal concentrations of chromium at 1.0, 1.4, and 1.6 microg/ml. Survival and fecundity were significantly reduced by chromium. Fecundity was higher in the chromium treatments than in the control group at the beginning of the reproductive period; however, overall, the highest fecundity was observed in the control. Life expectancy, net growth rate, and generation time were also significantly reduced by chromium. The population growth rate (lambda) was higher in the treated animals than in the controls. The differences in lambda between the treated animals and the controls (deltalambda) were almost completely due to the differences in the life tables observed during the first three weeks of life. The differences in survival between the treated and control animals did not contribute to deltalambda. The contribution to deltalambda of the slight increase in age-specific fecundity in the early reproductive events compensated for the marked decrease in overall fecundity in the treated animals. The complex effects of chromium enrichment on D. gyrociliatus underline the importance of analyzing both individual and population responses when assessing the effects of pollutants on organisms. Our results confirm that D. gyrociliatus might serve as an indicator species in confined areas of polluted seawater such as lagoons and harbors.

Age Factors↗
PubMed2003

Alpha-tocopherol supplementation on chromium toxicity: a study on rat liver and kidney cell membrane.

Membrane damage is one of the important consequence of chromium, an environmental toxicant, to produce cytotoxicity, alpha-tocopherol, a membrane protectant can be used to reduce the chromium-induced membrane damage. In the present study, the impact of chromium in presence and absence of alpha-tocopherol was studied on plasma membrane of liver and kidney in male Wistar rats (80-100 g body weight). Significant increase in membrane cholesterol level as well as significant decrease in membrane phospholipid level in chromium exposed (0.8 mg/100 g body weight/d, i.p., for 4 weeks) animals suggest structural alteration of both liver and kidney plasma membrane. The alkaline phosphatase, total ATPase and Na(+)-K(+)-ATPase activities of plasma membrane were significantly decreased in both liver and kidney after chromium treatment. However, alpha-tocopherol (30 mg/100 g diet) supplementation can restrict the changes in these membrane-bound enzyme activities. Thus, the usefulness of dietary supplementation of alpha-tocopherol to restrain the chromium-induced membrane damage is suggested.

Animals↗
PubMed1977

[Use of colored samples in the detection of occupational exposure to allergic effects of chromium and nickel compounds].

By using a coloured sample with diphenylcarbazide, chromium content in raw materials and industrial intermediate products was determined. At the same time chromium content was determined quantitatively by atomic absorption. The method was said to be simple and easy to be done in any industrial physician's conditions. The sample's sensitivity was said to be 1:100 000. Results of the determinations indicated that protective leather gloves contained considerable content of chromium, and chromium-free machine oils and lubricants were polluted with chromium's minute quantities as the oils and lubrications were being used. It was stated that coloured samples aiming at the detection of chromium, cobalt and nickel should be routinely used in preventive activity of industrial physicians.

Chromium↗
PubMed2004

[Examination of nickel and chromium contents in selected herbs, herbal fruit teas and their infusions].

The aim of this study was to determine the contents of nickel and chromium (the trace elements that are necessary for the human organism only in specified amounts) in selected dry herbs, herbal-fruit teas and their water extracts. This examination was expected to answer the question whether infusions or decoctions may constitute the additional source of these elements, or whether the amounts of nickel and chromium included in them may be dangerous for the human organism. The samples were dry mineralized at the temperature of 450 degrees C. Atomic absorption spectrometry (AAS) was performed using SOLAAR M5 appliance produced by a US-based Thermo Elemental company; nickel contents were determined from the organic phase, and chromium directly from the mineralisate. Nickel contents ranged on average from 0.56 microg/g to 2.68 microg/g in herbs and from 0.99 microg/g to 1.70 microg/g in herbal fruit teas. On average 40.0% to 82.5% of the amount present in dry, raw material passed into the infusions. The determined amounts of chromium ranged from 0.57 microg/g to 1.36 microg/g in herbs, and from 0.47 microg/g to 1.17 microg/g in herbal fruit teas (average values). The maximum extraction of this element into the infusion or decoction equaled 85.0%. The contents of nickel and chromium in the examined dry herb samples were comparable to results obtained by authors of the other papers. Infusions or decoctions of the examined herbs and herbal fruit teas contain the amounts of these elements that do not harm health and may constitute an additional source of nickel and chromium for the human organism.

Carcinogens, Environmental↗
PubMed1991

Trivalent chromium, in atherosclerosis and diabetes.

The known effects of trivalent chromium (Cr) in lowering blood levels of low density lipoproteins (LDL), raising high density lipoproteins (HDL) and improving glucose tolerance are summarised. Chromium deficiency cannot easily be established by direct means, but can be inferred by the reversal of symptoms and signs following the administration of trivalent chromium. This evidence can be supported by knowledge or suspicion of a deficiency in the diet, common in those who use highly refined cereal foods. It is considered that the beneficial effects of chromium repletion are now so well established and the trivalent form is so free of toxicity that it should now be used in clinical medicine for the benefit of those with some forms of diabetes and its complications and those suffering from atherosclerosis. Of perhaps more importance is the public health aspect, since most chromium is discarded in the cereal refinement process, we now have added evidence for a return to the diets in which complex carbohydrates predominated. In those who refuse or are unable to do this, possibly the addition of chromium to their drinking water may be of value.

Animals↗