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Title
chromium picolinate supplementation and resistive training by older men: effects on iron-status and hematologic indexes.
Author
Campbell WW; Beard JL; Joseph LJ; Davey SL; Evans WJ
Address
Donald W Reynolds Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock 72205-7199, USA.
Source
Am J Clin Nutr, 66(4):944-9 1997 Oct
Abstract
chromium competes with iron for binding to transferrin, and high-dose chromium supplementation has been hypothesized to adversely affect iron status. This study examined the effects of chromium picolinate supplementation on hematologic indexes and selected indexes of iron status in 18 men aged 56-69 y who participated in an introductory resistive training program. The men were randomly assigned (double-blind design) to groups (n = 9) that consumed either 17.8 mumol Cr/d (924 micrograms Cr/d) as chromium picolinate or a low-chromium placebo for 12 wk while engaging in resistive training twice weekly (3 sets of 8-12 repetitions at 80% of one repetition maximum for 5 exercises). Hematocrit, hemoglobin, red blood cell (erythrocyte) count, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, red blood cell distribution width, platelet count, and mean platelet volume were within normal clinical ranges and were unchanged by either chromium picolinate supplementation or resistive training. Resistive training decreased total-iron-binding capacity from 38.4 +/- 9.3 to 27.3 +/- 5.6 mumol/L (P < 0.0001) and increased transferrin saturation from 35.7 +/- 16.3% to 45.4 +/- 16.9% (P = 0.050). chromium picolinate supplementation did not influence these responses. Serum iron concentrations and serum ferritin concentrations were unchanged by either resistive training or chromium picolinate supplementation. These data suggest that high-dose chromium picolinate supplementation for 12 wk did not influence hematologic indexes or indexes of iron metabolism or status in older men. The decrease in total-iron-binding capacity and increase in transferrin saturation (%) with resistive training are largely opposite to changes associated with iron depletion and suggest a novel effect of resistive training on iron transport.

Title
[Effect of chromium yeast and chromium picolinate on body composition of obese, non-diabetic patients during and after a formula diet
Author
Bahadori B; Wallner S; Schneider H; Wascher TC; Toplak H
Address
Ambulanz f ur Diabetes und Stoffwechsel der Medizinischen Universit atsklinik, Graz, Osterreich.
Source
Acta Med Austriaca, 24(5):185-7 1997
Abstract
The objective of this study was to assess the effects of chromium yeast and chromium picolinate on lean body mass during and after weight reduction with a very-low-calorie diet. 36 obese (BMI 33.7 +/- 5.4 kg/m2), non-diabetic patients aged 45 +/- 6 years undergoing a 8-week very-low-calorie diet followed by a 18-week maintenance period. During the whole 26 week treatment period subjects received either placebo or chromium yeast (200 micrograms/d) or chromium-picolinate (200 micrograms/d) in a double-blind manner. Body weight was measured as BMI and body composition after calculation from skinfold thickness. As a result all three groups showed comparable weight loss after 8 and 26 weeks. Lean body mass was reduced in all groups after 8 weeks. However, after 26 weeks chromium picolinate supplemented subjects showed increased lean body mass (p < 0.029) whereas the other treatment groups still had reduced lean body mass. chromium picolinate, but not chromium yeast, is able to increase lean body mass in obese patients in the maintenance period after a very-low-calorie diet without counteracting the weight loss achieved.

Title
chromium supplementation and resistance training: effects on body composition' strength' and trace element status of men [see comments
Author
Lukaski HC; Bolonchuk WW; Siders WA; Milne DB
Address
US Department of Agriculture' Agricultural Research Service' Grand Forks Human Nutrition Research Center' ND' USA.
Source
Am J Clin Nutr, 63(6):954-65 1996 Jun
Abstract
The effects of 8 wk of daily chromium supplementation (3.3-3.5 mumol as chromium chloride or chromium picolinate) or placebo (0.1 mumol Cr) and weight training were examined in 36 men in a double-blind design. Strength' mesomorphy' fat-free mass' and muscle mass increased with resistance training independently of chromium supplementation (P < 0.0001). Protein' magnesium' zinc' copper' and iron intakes equalled or exceeded the recommended dietary allowance (RDA) or estimated safe and adequate daily dietary intake (ESADDI) during training and did not change significantly from pretraining intakes (P > 0.05). chromium supplementation increased the serum chromium concentration and urinary chromium excretion without a difference as a result of the chemical form of chromium (P < 0.05). Resistance training was associated with a significant decrease (P < 0.05) in serum ferritin' total-iron-binding capacity' transferrin saturation' the ratio of enzymatic to immunoreactive ceruloplasmin' and plasma copper' independently of chromium supplementation. However' transferrin saturation was decreased more with chromium picolinate supplementation (24%) than with chromium chloride or placebo (10-13%). Compared with pretraining values' urinary magnesium excretion increased (P < 0.05) and urinary zinc output tended to decrease during the first 4 wk of resistance training and then returned to baseline values for the final 4 wk' which suggests an adaptation in mineral excretion in response to weight training. These findings suggest that routine chromium supplementation has no beneficial effects on body- composition change or strength gain in men. Whether chromium supplementation of individuals with diminished chromium nutriture facilitates propitious changes in body structure and function remains to be determined.

Title
Effects of chromium picolinate on body composition.
Author
Trent LK; Thieding-Cancel D
Address
Naval Health Research Center' San Diego' CA 92186-5122' USA.
Source
J Sports Med Phys Fitness, 35(4):273-80 1995 Dec
Abstract
OBJECTIVE: This study explored the efficacy of chromium picolinate as a fat-reduction aid for obese individuals enrolled in a physical exercise program. EXPERIMENTAL DESIGN: The study employed a double-blind' placebo-controlled protocol and lasted for 16 weeks. SETTING: The physical conditioning programs were conducted on Navy bases (gymnasium' athletic field' etc.) and met a minimum of three times per week for at least 30 minutes of aerobic exercise. PARTICIPANTS: Participants were healthy' active-duty Navy personnel (79 men' 16 women) who exceeded the Navy`s percent body fat standards of 22% fat for men' 30% for women. Mean age was 30.3 years; racial distribution was 76% white' 16% black' and 8% other. Comparisons between the 95 study completers and the 109 dropouts revealed no significant differences in demographics or baseline percent body fat. INTERVENTIONS: Bottles of capsules containing either 400 micrograms chromium picolinate or a placebo were distributed to the designated individuals by their fitness program coordinator. Participants took one capsule per day and kept a log of their daily exercise activities. They also completed a pre-post questionnaire concerning their health and lifestyle habits. MEASURES: Primary outcome measures were percent body fat' body weight' and lean body mass. Percent body fat was computed from body circumference measurements and height. Analyses controlled for diet and exercise. RESULTS: At the end of 16 weeks' the group as a whole had lost a small amount of weight and body fat. However' the chromium group failed to show a significantly greater reduction in either percent body fat or body weight' or a greater increase in lean body mass' than did the placebo group. CONCLUSIONS: It was concluded that chromium picolinate was ineffective in enhancing body fat reduction in this group and could not be recommended as an adJuvant to Navy weight-loss programs in general.

Title
chromium picolinate.
Author
Reading SA
Address
Department of Pharmacology and Therapeutics' University of South Florida College of Medicine' USA.
Source
J Fla Med Assoc, 83(1):29-31 1996 Jan
Abstract
chromium picolinate is a dietary supplement gaining in popularity among Americans' especially those seeking a weight-reduction program. Although the mechanism(s) responsible for the purported actions of chromium picolinate have not been thoroughly investigated' studies suggest that the biochemical' physiological' and behavioral actions of chromium picolinate may be a consequence of the effects of picolinic acid on the central nervous system. Analogues of picolinic acid have been shown to induce profound alterations in the metabolism of serotonin' dopamine' and norepnephrine in brain. Thus' caution should be used with chromium picolinate supplements especially by individuals prone to behavioral disorders.

Title
chromium picolinate supplementation for diabetes mellitus.
Author
Fox GN; Sabovic Z
Address
Mercy Health System-Northern Region Family Practice Residency, Toledo, Ohio 43624, USA. foxgary@aol.com
Source
J Fam Pract, 46(1):83-6 1998 Jan
Abstract
chromium picolinate is a widely available nutritional supplement marketed for a plethora of afflictions. There is some evidence, including results from human studies, that it has a role in glucose homeostasis. We report the case of a 28-year-old woman with an 18-year history of type 1 diabetes mellitus whose glycosylated hemoglobin (Hb A1c) declined from 11.3% to 7.9% 3 months after initiation of chromium picolinate, 200 micrograms 3 times daily. chromium picolinate continues to fall squarely within the scope of "alternative medicine," with both unproven benefits and unknown risks. It deserves closer scrutiny with additional prospective, randomized, double-blind, placebo-controlled trials to evaluate its efficacy in improving outcomes in patients with diabetes. A brief review of the literature was done to assist physicians who are being called upon to counsel and treat patients who are engaging in alternative therapies.

Title
Lack of toxicity of chromium chloride and chromium picolinate in rats.
Author
Anderson RA; Bryden NA; Polansky MM
Address
Nutrient Requirements and Functions Laboratory' Beltsville Human Nutrition Research Center' U.S. Department of Agriculture' ARS' Maryland 20705-2350' USA.
Source
J Am Coll Nutr, 16(3):273-9 1997 Jun
Abstract
OBJECTIVE: To evaluate the safety of chromium (Cr) as a nutrient supplement. Several recent studies have reported beneficial effects of supplemental Cr at levels higher than the upper limit of the suggested intake for Cr. Trivalent Cr is considered relatively nontoxic but some recent unconfirmed studies have questioned its toxicity. We evaluated the toxicity of Cr chloride and a more bioavailable form of trivalent Cr' Cr tripicolinate. METHODS: Harlan Sprague Dawley rats (4 weeks of age) were fed a stock diet to which was added 0' 5' 25' 50 or 100 mg of Cr per kg of diet as chloride or picolinate. Fasting blood samples were taken at 11 and 17 weeks and animals sacrificed at 24 weeks of age. Lack of toxicity was demonstrated by blood and histological measurements. chromium incorporation into tissues was determined by graphite furnace atomic absorption. RESULTS: There were no statistically significant differences in body weight' organ weights or blood variables among all the groups tested at 11' 17 and 24 weeks. Blood variables measured were glucose' cholesterol' triglycerides' blood urea nitrogen' lactic acid dehydrogenase' transaminases' total protein and creatinine. Histological evaluation of the liver and kidney of control and animals fed 100 mg/kg Cr as Cr chloride or picolinate also did not show any detectable differences. Liver and kidney Cr concentrations increased linearly for both the Cr chloride and picolinate fed animals. CONCLUSIONS: These data demonstrate a lack of toxicity of trivalent Cr' at levels that are on a per kg basis' several thousand times the upper limit of the estimated safe and adequate daily dietary intake for humans. Animals consuming the picolinate supplemented diets had several-fold higher Cr concentrations in both the liver and kidney than those fed Cr chloride.

Title
chromium and exercise training: effect on obese women.
Author
Grant KE; Chandler RM; Castle AL; Ivy JL
Address
Department of Kinesiology and Health Education' University of Texas at Austin 78712' USA.
Source
Med Sci Sports Exerc, 29(8):992-8 1997 Aug
Abstract
chromium supplementation may affect various risk factors for coronary artery disease (CAD) and non-insulin-dependent diabetes mellitus (NIDDM)' including body weight and composition' basal plasma hormone and substrate levels' and response to an oral glucose load. This study examined the effects of chromium supplementation (400 micrograms.d-1)' with or without exercise training' on these risk factors in young' obese women. chromium picolinate supplementation resulted in significant weight gain in this population' while exercise training combined with chromium nicotinate supplementation resulted in significant weight loss and lowered the insulin response to an oral glucose load. We conclude that high levels of chromium picolinate supplementation are contraindicated for weight loss in young' obese women. Moreover' our results suggest that exercise training combined with chromium nicotinate supplementation may be more beneficial than exercise training alone for modification of certain CAD and NIDDM risk factors.

Title
Elevated intakes of supplemental chromium improve glucose and insulin variables in individuals with type 2 diabetes.
Author
Anderson RA; Cheng N; Bryden NA; Polansky MM; Cheng N; Chi J; Feng J
Address
Beltsville Human Nutrition Research Center, U.S. Department of Agriculture, Maryland 20705-2350, USA. anderson@307.bhnrc.usda.gov
Source
Diabetes, 46(11):1786-91 1997 Nov
Abstract
chromium is an essential nutrient involved in normal carbohydrate and lipid metabolism. The chromium requirement is postulated to increase with increased glucose intolerance and diabetes. The objective of this study was to test the hypothesis that the elevated intake of supplemental chromium is involved in the control of type 2 diabetes. Individuals being treated for type 2 diabetes (180 men and women) were divided randomly into three groups and supplemented with: 1) placebo, 2) 1.92 micromol (100 microg) Cr as chromium picolinate two times per day, or 3) 9.6 micromol (500 microg) Cr two times per day. Subjects continued to take their normal medications and were instructed not to change their normal eating and living habits. HbA1c values improved significantly after 2 months in the group receiving 19.2 pmol (1,000 microg) Cr per day and was lower in both chromium groups after 4 months (placebo, 8.5 +/- 0.2%; 3.85 micromol Cr, 7.5 +/- 0.2%; 19.2 micromol Cr, 6.6 +/- 0.1%). Fasting glucose was lower in the 19.2-micromol group after 2 and 4 months (4-month values: placebo, 8.8 +/- 0.3 mmol/l; 19.2 micromol Cr, 7.1 +/- 0.2 mmol/l). Two-hour glucose values were also significantly lower for the subjects consuming 19.2 micromol supplemental Cr after both 2 and 4 months (4-month values: placebo, 12.3 +/- 0.4 mmo/l; 19.2 micromol Cr, 10.5 +/- 0.2 mmol/l). Fasting and 2-h insulin values decreased significantly in both groups receiving supplemental chromium after 2 and 4 months. Plasma total cholesterol also decreased after 4 months in the subjects receiving 19.2 micromol/day Cr. These data demonstrate that supplemental chromium had significant beneficial effects on HbA1c, glucose, insulin, and cholesterol variables in subjects with type 2 diabetes. The beneficial effects of chromium in individuals with diabetes were observed at levels higher than the upper limit of the Estimated Safe and Adequate Daily Dietary Intake.

Title
A prediction of chromium(III) accumulation in humans from chromium dietary supplements.
Author
Stearns DM; Belbruno JJ; Wetterhahn KE
Address
Department of Chemistry' Dartmouth College' Hanover' New Hampshire
03755-3564' USA.
Source
FASEB J, 9(15):1650-7 1995 Dec
Abstract
It has been proposed that 90% of American`s diets are deficient in the trace essential mineral chromium. Several chromium(III) dietary supplements are currently available to alleviate this deficiency. We show here that the same pharmacokinetic models that have been used to quantitate absorption of chromium(III) in humans predict that ingested chromium(III) will accumulate and be retained in human tissues for extended periods. Calculations were carried out with the popular supplement chromium picolinate as an example' but may be applied to any chromium(III) complex. Results from these calculations were compared to clinical data obtained from chromium(III) absorption/retention studies in humans. The models predict that chromium(III) can accumulate in human tissues to reach the levels at which DNA damage has been observed in animals and in vitro. The use of chromium supplements for extended periods or in excess dosages should be reevaluated in terms of these established models because the possible long-term biological effects of chromium accumulation in humans are poorly understood.

Title
The effect of chromium picolinate on the liver levels of trace elements
Author
Aguilar MV; Jorge AM; Mateos CJ; Garc]ia J; Laborda JM; Meseguer I; Mart]inez-Para MC; Gonz]alez MJ
Address
Departamento de Nutrici]on y Bromatolog]ia' Facultad de Farmacia'
Universidad de Alcal]a de Henares' Espa~na.
Source
Nutr Hosp, 10(6):373-6 1995 Nov-Dec
Abstract
chromium picolinate has been implicated as a lipid and carbohydrate reducing agent' and therefore it may be a valuable adJunct to the treatment and prevention of diabetes and heart disease. This compound is inexpensive and apparently nontoxic. In this work' we have determined the influence of its administration (100' 200' 500 micrograms Cr/ml' for 7 and 21 days) on hepatic content of Zn' Mn' Cu and Fe of male Wistar rats. The results show a variation of the levels of these elements after the administration of chromium picolinate' although the differences are only significantly (p < 0.01) in the case of Mn. This influence is dose-dependent' occurring a decrease of 72% in the group treated with 500 micrograms/ml (Pic-500) respect to the content of control group.

Title
Anabolic effects of insulin on bone suggest a role for chromium picolinate in preservation of bone density.
Author
McCarty MF
Source
Med Hypotheses, 45(3):241-6 1995 Sep
Abstract
Activation of osteoclasts by parathyroid hormone (PTH) is mediated by PTH stimulation of osteoblasts' and is dependent on a PTH-induced rise in protein kinase C activity. Physiological levels of insulin reduce the ability of PTH to activate protein kinase C in osteoblasts' suggesting that insulin may be a physiological antagonist of bone resorption. In addition' insulin is known to promote collagen production by osteoblasts. These findings imply that efficient insulin activity may exert an anabolic effect on bone' and rationalize the many clinical studies demonstrating reduced bone density in Type I diabetes. Recently' the insulin-sensitizing nutrient chromium picolinate has been found to reduce urinary excretion of hydroxyproline and calcium in postmenopausal women' presumably indicative of a reduced rate of bone resorption. This nutrient also raised serum levels of dehydroepiandrosterone-sulfate' which may play a physiological role in the preservation of postmenopausal bone density. The impact of chromium picolinate (alone or in conJunction with calcium and other micronutrients) on bone metabolism and bone density' merits further evaluation in controlled studies.

Title
Nutritional factors influencing the glucose/insulin system: chromium.
Author
Anderson RA
Address
Nutrient Requirements and Functions Laboratory, United States Department of Agriculture, Beltsville, Maryland 20705-2350, USA.
Source
J Am Coll Nutr, 16(5):404-10 1997 Oct
Abstract
chromium (Cr) improves the glucose/insulin system in subjects with hypoglycemia, hyperglycemia, diabetes and hyperlipemia with no detectable effects on control subjects. chromium improves insulin binding, insulin receptor number, insulin internalization, beta cell sensitivity and insulin receptor enzymes with overall increases in insulin sensitivity. There have been several studies involving Cr supplementation of subjects with NIDDM and/or lipemia and most have reported beneficial effects of Cr on the glucose/insulin system. In a recent study, Chinese subjects with NIDDM were divided into three groups of 60 subjects and supplemented with placebo, 100 or 500 micrograms of Cr as chromium picolinate 2 times per day for 4 months. Improvements in the glucose/insulin system were highly significant in the subjects receiving 500 micrograms twice per day with less or no significant improvements in the subjects receiving 100 micrograms twice per day after 2 and 4 months. In summary, Cr is involved in the control of the glucose/insulin system and the amount, and likely form of chromium, are critical when evaluating the role of chromium in this system.

Title
The effectiveness of long-term supplementation of carbohydrate, chromium, fibre and caffeine on weight maintenance.
Author
Pasman WJ; Westerterp-Plantenga MS; Saris WH
Address
Department of Human Biology, Maastricht University, The Netherlands.
W.Pasman@HB.Unimass.N1
Source
Int J Obes Relat Metab Disord, 21(12):1143-51 1997 Dec
Abstract
OBJECTIVE: To investigate whether supplementation of carbohydrate, chromium, dietary fibre and caffeine is effective for maintenance of weight-loss in the long-term. DESIGN: A longitudinal, double-blind, randomly assigned intervention study of 16 months with supplementation of either 50g of carbohydrates (CHO), 200 micrograms chromium-picolinate (Cr-Pic), 20g of soluble fibre plus 100 mg caffeine (CHO+) or 50g of plain CHO, for 16 months besides a very low energy diet (VLED) during the first two months. SUBJECTS: Thirty-three female obese subjects (age, 34.8 +/- 7.0 y; body weight (BW): 85.5 +/- 10.0 kg; body mass index (BMI) 31.2 +/- 3.7 kg.m-2) participated, 13 subjects were supplemented with CHO+, 11 subjects were supplemented with CHO and 9 subjects served as a control group. MEASUREMENTS: SW, body composition, energy intake and blood parameters were measured before the VLED (0), after the VLED at 2 months (2), and at 4, 10 and 16 months. RESULTS: The amount and course of relapse of BW was equal for the supplemented and control groups. The average regain at 16 months (the weight gained as a percentage of the total weight loss during the VLED) was 66.1 +/- 81.2%, and was not different between the groups. No differences in body composition were found between the groups at 16 months. The CHO supplements resulted in significantly elevated energy percentage (En %) intake of CHO daily, in both supplemented groups, although this did not result in less regain. Pearson correlation analysis for all subjects revealed that the more fat consumed, the more regain was found at 16 months (r = 0.41, P < 0.05). A high CHO consumption was correlated with less regain (r = -0.40, P = 0.05). Furthermore, chromium intake did not result in significant changes in blood parameters and body composition. CONCLUSION: Although additional supplementation of CHO, chromium, dietary fibre and caffeine intake did not affect BW, the En % CHO daily was increased significantly. Our results indicate that a high En% intake of CHO and a low En% intake of fat daily is beneficial for prevention of weight regain.

Title
Effect of chromium picolinate on growth' body composition' and tissue accretion in pigs.
Author
Boleman SL; Boleman SJ; Bidner TD; Southern LL; Ward TL; Pontif JE;
Pike MM
Address
Department of Animal Science' Louisiana State University Agricultural Center' Baton Rouge 70803' USA.
Source
J Anim Sci, 73(7):2033-42 1995 Jul
Abstract
An experiment was conducted to evaluate the effect of dietary chromium picolinate (CrP) on growth and body composition of pigs. Twenty-four barrows (three from each of eight litters) were randomly allotted within litter to one of three treatments: 1) basal (B) diet from 19.1 to 106.4 kg BW (Control); 2) B from 19.1 to 57.2 kg BW and then B + 200 ppb of chromium as CrP from 57.2 to 106.4 kg BW (CrP-F); and 3) B + 200 ppb of chromium as CrP from 19.1 to 106.4 kg BW (CrP- GF). Average daily gain and ADFI were reduced (P < .08) and first rib fat thickness was increased (P < .08) in pigs fed CrP-GF compared with pigs fed the Control diet. Specific gravity of the carcass was not affected (P > .10) by treatment. Tenth rib fat was reduced (P < .01) in pigs fed CrP-F compared with pigs fed CrP-GF' and percentage of muscle was increased in pigs fed CrP-F (P < .09) compared with pigs fed either the Control or CrP-GF diets. Leaf fat (P < .05) and lung weights (P < .08) were reduced in pigs fed CrP-F compared with pigs fed CrP-GF. As determined by physical-chemical separation' pigs fed CrP-GF had an increased (P < .07) percentage of intermuscular fat compared with pigs fed the Control or CrP-F diets. Pigs fed CrP-F had a lesser (P < .07) percentage of total fat and a greater (P < .07) percentage of muscle than pigs fed the Control or CrP-GF diets. As determined by mechanical-chemical separation' pigs fed CrP-F had a greater (P < .10) percentage of moisture than pigs fed the Control diet and a lesser (P < .10) percentage of fat and a greater (P < .06) percentage of ash than pigs fed the Control or CrP-GF diets. Pigs fed CrP-GF had an increased (P < .04) daily fat accretion compared with pigs fed CrP-F. Sensory and shear force values were not affected by CrP' with the exception that meat from pigs fed CrP-GF had a greater (P < .10) shear force value than meat from pigs fed CrP-F. These results suggest that dietary supplementation of CrP in the finishing phase of pig production may increase muscle and decrease fat deposition; however' not all measures of muscling or fatness were improved by CrP.

Title
Effects of dietary chromium picolinate supplementation on growth' carcass characteristics' and accretion rates of carcass tissues in growing-finishing swine.
Author
Mooney KW; Cromwell GL
Address
Department of Animal Sciences' University of Kentucky' Lexington 40546' USA.
Source
J Anim Sci, 73(11):3351-7 1995 Nov
Abstract
An experiment was conducted to evaluate the effects of chromium picolinate (CrP) on growth performance' carcass composition' and tissue accretion rates in pigs from 27 to 109 kg BW. Seven littermate sets of Yorkshire-Hampshire barrows' individually penned' were fed a fortified' corn-soybean meal basal diet (.95% lysine from 27 to 55 kg; .80% lysine from 55 to 109 kg) supplemented with 0 or 200 micrograms/kg of Cr from CrP. Addition of CrP increased (P < .09) ADG but did not affect ADFI or feed:gain ratio. Average and 10th rib backfat and longissimus muscle area were not affected by Cr supplementation. The right side of the carcass was physically dissected into muscle' fat' bone' and skin. Additionally' five pigs were killed for determination of initial body composition. Dietary CrP addition increased (P < .02) the percentage of muscle and decreased (P < .06) the percentage of fat. Total gain of dissected bone and skin were not different between treatments' but CrP increased (P < .06) the total gain of dissected muscle and decreased (P < .02) the total gain of dissected fat. Also' CrP increased the daily accretion rates of muscle (P < .05) and bone (P < .03) and decreased the daily accretion rate of fat (P < .05). The left side of the carcass was ground for determination of water' protein' lipid' and ash. The addition of CrP to the diet increased the percentage (P < .09) and accretion rate (P < .09) of water and increased the percentage (P < .004)' total gain (P < .02)' and accretion rate (P < .02) of protein while decreasing (P < .04) the percentage of lipid. Pigs fed CrP also had a decreased (P < .004) percentage of lipid in the dissected carcass muscle. Water' protein' and ash from the dissected muscle were not different between treatments. These results suggest that CrP supplementation throughout the entire growing-finishing phase increases the total gain and accretion rate of muscle while decreasing the total gain and accretion rate of fat. This results in carcasses with an increased percentage of muscle and decreased percentage of fat.

Title
chromium picolinate modulates rat vascular smooth muscle cell intracellular calcium metabolism.
Author
Moore JW; Maher MA; Banz WJ; Zemel MB
Address
Departments of Nutrition and Medicine, The University of Tennessee, Knoxville, TN 37996-1900, USA.
Source
J Nutr, 128(2):180-4 1998 Feb
Abstract
We have previously shown that insulin attenuates vasoconstriction, accelerates both vascular relaxation and [Ca2+ i recovery from pressor agonist-induced Ca2+ loads, and stimulates Ca2+-ATPase gene expression in rat and human vascular smooth muscle cells (VSMC). Moreover, these functions are impaired in VSMC from both insulin resistant and insulinopenic rats, suggesting that hypertension in insulin resistant states may result, in part, from impaired insulin-regulation of VSMC Ca2+ transport. Accordingly, we have now evaluated the effect of improving cellular insulin sensitivity with chromium picolinate (CrPic) on regulation of VSMC Ca2+ transport. Cultured VSMC from rats were grown from passage to confluence in the presence or absence of 1 &mgr;mol/L CrPic, maintained in a quiescent medium for 24 h and incubated with or without insulin (10(-8) mol/L) for the final 2 h. Cells were then harvested and RNA and protein extracted for Northern and Western blot analysis, respectively. Insulin caused a significant stimulation of plasmalemmal Ca2+-ATPase mRNA and protein (P < 0.05). A comparable stimulation of the mRNA and protein levels was caused by CrPic in the absence of insulin (P < 0.05), while the CrPic + insulin treatment caused a greater percentage stimulation of the Ca2+-ATPase mRNA level than either separate treatment (P < 0.05). Fluorometric analysis of the rate of [Ca2+ i recovery following stimulation with arginine vasopressin support these findings: insulin caused an 83% increase, CrPic caused a 35% increase and insulin + CrPic caused a 133% increase in [Ca2+ i recovery rate. These data suggest that CrPic may be an effective modality to reduce VSMC [Ca2+ i loads and thereby reduce peripheral vascular resistance in insulin resistant states.

 

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