Cr Supplementation Research Articles

Can Creatine Supplementation Interfere with Muscle Strength and Fatigue in Brazilian National Level Paralympic Powerlifting?

The aim of the present study was to analyze the effect of creatine (Cr) supplementation on peak torque (PT) and fatigue rate in Paralympic weightlifting athletes. Eight Paralympic powerlifting athletes participated in the study, with 25.40 ± 3.30 years and 70.30 ± 12.15 kg. The measurements of muscle strength, fatigue index (FI), peak torque (PT), force (kgf), force (N), rate of force development (RFD), and time to maximum isometric force (time) were determined by a Musclelab load cell. The study was performed in a single-blind manner, with subjects conducting the experiments first with placebo supplementation and then, following a 7-day washout period, beginning the same protocol with creatine supplementation for 7 days. This sequence was chosen because of the lengthy washout of creatine. Regarding the comparison between conditions, Cr supplementation did not show effects on the variables of muscle force, peak torque, RFD, and time to maximum isometric force (p > 0.05). However, when comparing the results of the moments with the use of Cr and placebo, a difference was observed for the FI after seven days (U3: 1.12; 95% CI: (0.03, 2.27); p = 0.02); therefore, the FI was higher for placebo. Creatine supplementation has a positive effect on the performance of Paralympic powerlifting athletes, reducing fatigue index, and keeping the force levels as well as PT.

Creatine supplementation does not promote tumor growth or enhance tumor aggressiveness in Walker-256 tumor-bearing rats.

This study aimed to analyze the effect of creatine (Cr) supplementation on tumor microenvironment, evaluating the parameters of tumor aggressiveness. Sixteen male Wistar rats were randomly assigned to 2 groups (n=8/group): Tumor-bearing (T) and tumor-bearing supplemented with Cr (TCr). Cr supplementation was provided in drinking water for a total of 21 d. After 11 d of Cr supplementation (TCr group) or water (T group), Walker-256 tumor cells were inoculated subcutaneously in the right flank of all rats, which kept receiving Cr supplementation (TCr group) or water (T group) for 10 more days. The total period of the experiment was 21 d. Tumor weight corresponded with approximately 3.5% ± 0.9% of animal body weight in the T group. Cr supplementation did not accelerate tumor growth or increase tumor size. The histopathological analysis demonstrated the presence of nuclear pleomorphisms and atypical nuclei, with the presence of low-differentiated tumor cells, in both groups. Cr supplementation did not alter apoptosis and cell proliferation markers, nor tumor capsule thickness and viable tumor area. Cr supplementation in Walker-256 tumor-bearing rats did not induce significant changes in tumor development, and did not interfere with the parameters of tumor aggressiveness, such as the level of cell differentiation and proliferation.

Potential Ameliorative Effects of Chromium Supplementation on Glucose Metabolism, Obesity, and Genomic Stability in Prediabetic Rat Model.

Chromium (III) (Cr(III)) effect on improving glucose, body mass loss, and genomic stability has been extensively studied in models of type 2 diabetes. However, there is a lack of studies evaluating its effect on prediabetes. Thus, this study evaluates the effects of Cr(III) as dietetic supplementation on glucose metabolism, obesity, and genomic stability on prediabetic rat model using high-invert sugar. Male Wistar rats were divided randomly into four treatment groups: (1) control, receiving standard diet (control); (2) prediabetic (PD), receiving a 32% of invert sugar; (3) Cr(III), receiving chromium (III) chloride (CrCl3•6H2O) (58.4mg/L); and (4) Cr(III) + PD, receiving CrCl3•6H2O in combination with high-invert sugar. Cr(III) supplementation significantly reduced blood glucose (123.00 ± 8.29mg/dL vs. 115.30 ± 9.31mg/dL, p = 0.015) and partially reduced area under the 120-min blood glucose response curve (AUC) in PD rats (p = 0.227). Moreover, Cr(III) attenuated weight gain (187.29 ± 38.56g vs. 167.22 ± 29.30g, p = 0.004), significantly reducing body mass index (0.68 ± 0.04g/cm2 vs. 0.63 ± 0.04g/cm2, p < 0.001), Lee index (0.30 ± 0.01 vs. 0.28 ± 0.01, p < 0.001), and peritoneal fat (p < 0.001). Regarding genomic stability, high-invert sugar, Cr(III), or the combination of both did not produce changes in oxidative stress, DNA damage in pancreas, or cytotoxicity markers. These data suggest that Cr(III) supplementation improved partially glucose metabolism and reduced obesity in rat model PD due to high-invert sugar without influence in genomic stability.

Research Note: Responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate in heat-stressed broilers

This study was conducted to investigate the dose responses of growth performance, immune traits, and small intestinal morphology to dietary supplementation of chromium propionate (CrPro) in heat-stressed broilers. A total of 252 1-day-old Cobb 500 male broilers were randomly assigned to 6 treatments with 7 replicate cages of 6 birds per cage. The dietary treatments consisted of a basal diet supplemented with 0, 0.2, 0.4, 0.8, 1.6, and 3.2 mg/kg Cr in the form of CrPro. The birds had ad libitum access to feed and tap water for an experimental period of 42 D. For induction of heat stress, the house temperature was set at 35°C ± 2°C from 22 to 42 D of age. No differences were detected among treatments in growth performance during the experimental period (P > 0.05). Serum IgA concentrations were not affected by treatment (P > 0.05). However, a quadratic response was detected for serum IgG (P < 0.01) and IgM (P < 0.01) concentration as dietary Cr supplementation was increased. The highest response of IgG and IgM in serum was observed for broilers fed a diet supplemented with 0.2 mg of Cr/kg. Dietary supplementation of Cr had no impacts on villus height, crypt depth, or the ratio of villus height to crypt depth in the jejunum and ileum. A quadratic response of villus height and the ratio of villus height to crypt depth and a linear response of crypt depth to increased dietary Cr supplementation were observed in the duodenum (P < 0.01). The results indicate that CrPro supplementation could modify the intestinal morphology of the duodenum and influence serum IgG and IgM concentrations in heat-stressed broiler chickens. Based on the results of this experiment, the 0.2-mg Cr/kg diet from CrPro increases immune response and intestinal health in heat-stressed broilers.

Comparative effects of inorganic and organic trace minerals (Zn, Se and Cr) supplementation on expression of ChTLR2b gene in broilers

Poultry is the fastest growing livestock sector in the developing countries. The global poultry sector is expected to continue to grow, as demand for poultry meat is driven by growing needs, population, rising incomes and urbanization. The present experiment was conducted to investigate the effect of inorganic and organic trace minerals supplementation on expression of ChTLR2b gene in broilers. A total of 216 broilers randomly divided into twelve groups and each group consisting of 18 broilers in 3 replicates. T1 group was kept as control. T2, T3 and T4 group was supplemented with zinc (40 mg/kg of feed) inorganic, organic and 50% organic form respectively. T5, T6 and T7 groups was supplemented with selenium (0.3 mg/kg of feed) from inorganic, organic and 50%organic form respectively. T8, T9 and T10 groups was supplemented with chromium (2 mg/kg of feed) from inorganic, organic form and 50% organic form respectively. T11 and T12 group was supplemented with combination of all 3 minerals from inorganic and organic form respectively. RT-PCR expression analysis of ChTLR2b gene in spleen revealed that maximum up regulation (3.8413 fold) was found in T3 group (supplemented with organic Zn @ 40 mg/Kg of feed), followed by T4 (3.5325 fold) whereas in bursa of fabricius the maximum up regulation (2.8921 fold) was found in T6 group followed by T12 (2.5310 fold ) as compared to control group. Up-regulation of gene expression ChTLR2b in bursa of fabricius and spleen indicates beneficial effect of organic trace minerals in potentiation of immune system in broilers.

Examination Of The Time Course Effect Of Creatine Supplementation On Acute Doxorubicin-induced Skeletal Muscle Dysfunction

Chemotherapy drugs such as doxorubicin (Dox) may cause skeletal muscle dysfunction, and supplementing the diet with creatine (Cr) could counteract skeletal muscle dysfunction. Very little has been done, however, exploring the time course effects of Cr on Dox-induced skeletal muscle dysfunction. PURPOSE: To examine the effects of Cr on skeletal muscle function 1, 3, and 5 days following Dox treatment. METHODS: Male rats were randomly assigned to the control group (Con), the doxorubicin group (Dox), the standard Cr diet (2% Cr for 4 weeks) and doxorubicin group (Cr1+Dox), or the Cr loading diet (4% Cr for 1 week followed by 2% Cr 3 weeks) and doxorubicin group (Cr2+Dox). After 4 weeks of feeding, Dox groups received 15 mg/kg Dox and Con received saline. At 1, 3, and 5 days post-injection, grip force and extensor digitorum longus (EDL) forces during a 100 s ex vivo fatigue protocol were measured. RESULTS: No between group differences in grip force were observed 1 day post injection, but at 3 days, a between group difference in grip force was observed (p=0.03) with Dox and Cr1+Dox having lower grip forces than Con (-9.8% and -10.5%, respectively, p<0.05), but this difference was not observed in Cr2+Dox. A between group difference in grip force was also observed at the 5 day time point (p<0.0001) with Dox, Cr1+Dox, and Cr2+Dox having lower grip force than Con (-19.9%, -37.2%, and -19.5%, respectively, p<0.05). With ex vivo EDL function, no between group differences were observed 1 day post injection, but at day 3, EDLs from Dox generated less force than Con at the 10 s through 40 s and the 70 s through 100 s time points (p<0.05), but these differences were not observed in Cr1+Dox and Cr2+Dox. At day 5, Cr1+Dox EDLs generated significantly less force than Con at every time point during the 100 s fatigue protocol (p<0.05), and Cr2+Dox EDLs generated significantly less force than Con at the 10 s through 40 s time points (p<0.05). CONCLUSIONS: Cr supplementation provided protection against Dox-induced muscle dysfunction 3 days post injection, and this protection was more evident with the Cr loading diet (Cr2). This myoprotection, however, was not observed 5 days post Dox injection suggesting that Cr’s benefit may be limited to protecting against the early phases of acute Dox myotoxicity.

Effect of 12 Weeks of Endurance Training Combined with Creatine Supplement, Photobiomodulation Therapy, or Both on Performance and Muscle Damage in Rats.

Background: Photobiomodulation therapy (PBMT) and creatine (Cr) intake have been used in conjunction with heavy training, but little is known about their possible effects during a long-term training program. Objective: We assessed long-term use of PBMT and Cr in an exercise training program. Methods: Twenty-five male Wistar rats weighing ∼300 g were randomly allocated to one of five groups: a nontraining control group, a training group, a training group receiving Cr, a training group receiving PBMT, and a training group receiving both PBMT and Cr. The training program consisted of 12 weeks of daily swimming training. PBMT was delivered in six points with a laser device (808 nm, 100 mW, 30 sec per point of irradiation, 3 J, 75 J/cm2). Results: All training groups showed significantly higher peak force and longer time to 50% decay of force, and lower creatine kinase (CK) levels than the nontraining control group, thus confirming the benefit of the training program. In all outcomes related to muscle performance, the groups receiving PBMT with or without Cr supplement performed significantly better (p < 0.05) peak force and time of force decay during an electrical stimulation protocol than all the other groups. In addition, CK levels were also significantly lower for the PBMT groups than for the other groups. Conclusions: We conclude that PBMT alone or in conjunction with Cr supplement during a 12-week training program resulted in significantly better muscle performance and lower levels of CK, a biochemical marker of muscle damage.

Effects of Bitter Melon and a Chromium Propionate Complex on Symptoms of Insulin Resistance and Type 2 Diabetes in Rat Models

Trivalent chromium (Cr) and bitter melon (Momordica charantia L., BM) have been shown to independently interact with the insulin signaling pathway leading to improvements in the symptoms of insulin resistance and diabetes in some animal models and human subjects. The aim of this study was to examine whether the combination of the two nutritional supplements could potentially have additive effects on treating these conditions in high-fat-fed streptozotocin (STZ)-induced diabetic rats. The experiment was conducted with 110 male Wistar rats divided into eleven groups and fed either a control or high-fat diet for 7 weeks. Half of the rats on the high-fat diet were injected with STZ (30 mg/kg body mass) to induce diabetes. The high-fat (HF) diets were then supplemented with a combination of Cr (as chromium(III) propionate complex, Cr3: either 10 or 50 mg Cr/kg diet) and bitter melon (lyophilized whole fruit: either 10 or 50 g/kg diet) for 6 weeks. After termination of the experiment, blood and internal organs were harvested for blood biochemical, hematological, and mineral (Cr) analyses using appropriate analytical methods. It was found that neither Cr(III) nor BM was able to significantly affect blood indices in HF and diabetic rats, but BM tended to improve body mass gain, blood glucose, and LDL cholesterol values, but decreased Cr content in the liver and kidneys of the Cr-co-supplemented type 2 diabetic model of rats. Supplementary Cr(III) had no appreciable effect on glucose and lipid metabolism in high-fat-fed STZ-induced diabetic rats. Supplementary BM fruit powder had some observable effects on body mass of high-fat-fed rats; these effects seem to be dampened when BM was co-administered with Cr. Cr(III) and BM appear to act as nutritional antagonists when both administered in food, probably due to binding of Cr by the polyphenol-type compounds present in the plant material.Graphical

Impacts of Chromium and Selenium-E on Cortisol Levels, Reproductive and productive Efficiency of Baladi Female Goats under Subtropical Conditions.

The present study was conducted during estrous cycle and pregnancy period in Baladi female goats to study the effect of chromium and selenium with vitamin E on blood serum cortisol concentration. Seventy-two of mature Baladi does with age ranged from 2 to 3 years old and the mean body weight was 25.1±1.5 kg was used under two conditions of winter and summer seasons (36 animals/season). The animals were randomly divided into three groups, the 1st group was kept as control and the 2nd group was supplemented by chromium (chromium chloridetrivalent), 0.8 mg/head/day. The 3rd group was intramuscularly injected twice a week with 2ml viteselen®, contained 0.5 mg selenium and 10.7 IU vitamin E (Se-E). Serum cortisol levels were assessed in the three experimental goats during the estrous and pregnancy periods. The results demonstrated that Goats supplementation with Cr or Se-E significantly decreased (P<0.05) serum cortisol concentrations than control during estrous cycle. In addition, Cr mostly lowered (P<0.05) cortisol than control, but Se-E thoroughly increased it during pregnancy. However, under mild season at pro-estrus phase Cr treatment increased cortisol significantly (P<0.05) than control. Also, during pregnancy period Cr decreased cortisol at Mid-Pregnancy and Late-Pregnancy periods; however, Se-E increased cortisol at the Late-Pregnancy period than the control group. Under hot season, Cr treatment decreased (P<0.05) cortisol during estrous cycle, pregnancy period. However, injection of Se-E decreased cortisol during estrous cycle and showed a contrary effect during pregnancy period. On the other side, Reproductive traits of female goats showed that, under mild season conditions Cr or Se-E supplementations did not have any effect on goat’s reproductive traits, in terms of conception rate, kidding rate, fertility rate, prolificacy and fecundity compared to control group. Under hot season conditions, Cr and Se-E improved both of fertility and conception rate, as well as, increased fecundity percentage more than control. Cr group had lowest prolificacy, however; Se-E had the highest one compared to control. Chromium group had significantly (P<0.05) higher birth weight of kids than control and Se-E either at mild or hot season. However, injection of Se-E did not affect litter birth weight under mild and hot conditions.So,It can be concluded that Cr and Se-E supplementation can enhanced the reproductive and productive traits of female Baladi goats under hot season.

Effects of chromium supplementation on inflammatory biomarkers: A systematic review and dose-response meta-analysis of randomized controlled trials

IntroductionAccumulating evidence suggests that chromium (Cr) supplementation may prevent inflammation, however, the results have been inconsistent. To derive a more precise estimation of the efficacy of Cr supplementation on inflammatory mediators such as tumor necrosis factor‐alpha (TNF‐α), high-sensitivity C‐reactive protein (hs-CRP), and interleukin‐6 (IL‐6), this systematic review and meta-analysis was performed. MethodsAn advanced search of PubMed and Scopus was conducted from inception to 14 April 2020 to find randomized controlled trials that assessed the effect of Cr supplementation on inflammation among the adult population. ResultsThe search resulted in identifying 10 articles which met the inclusion criteria for the systematic review. Our results indicated that Cr supplementation significantly decreased serum levels of hs-CRP (weighted mean differences (WMD): -0.95 mg/l; 95 % CI, -1.54 to -0.36, P = 0.002). Greater effects on hs-CRP were detected in trials using Cr picolinate and Cr chloride, dosage <300 μg with duration ≤12 weeks. Also, 12 weeks supplementation with Cr dinicocysteinate led to a significant reduction in the level of TNF-α but Cr picolinate did not show significant changes in serum levels of TNF-α. Moreover, both Cr picolinate and Cr dinicocysteinate had no significant differences in the level of serum IL-6 and IL-8. Although, a significant non-linear association was found between serum hs-CRP changes and study duration (Pnon-linearity = 0.03), we did not find any significant association between serum hs-CRP changes and dosage (Pnon-linearity = 0.86) with Cr picolinate supplementation. ConclusionSupplementation with Cr picolinate and Cr chloride at dose <300 μg for ≤12 weeks could significantly decrease serum hs-CRP levels.

Effect of Dietary Supplementation of Manganese, Chromium and Cobalt on Semen Qualities in Sahiwal Bulls

The present study was conducted to evaluate the effect of supplemental manganese (Mn), chromium (Cr) and cobalt (Co) on semen qualities in Sahiwal bulls. Twelve Sahiwal bulls divided into three groups T1, T2 and T3 based on their similar semen volume and concentration and were fed with 0, 1.5 and 2.0 times higher Mn, Cr and Co over and above the basal diet (ICAR, 2013) in T1, T2 and T3, respectively, for a period of 120 days. Semen was collected in all the groups twice a week and evaluated for quantitative and qualitative attributes. It was found that additional supplementation of Mn, Cr and Co had no influence on body weight gain, intake and digestibility of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF) and acid detergent fibre (ADF)]. Seminal mass motility, initial progressive motility, live spermatozoa, normal spermatozoa, intact acrosome and hypo-osmotic swelling test (HOST) positive sperm count was higher (P less than 0.05) in T3 group in comparison to T1 and T2 groups of fresh as well as frozen semen. Blood superoxide dismutase (SOD) activity was higher (P greator than 0.05) in both T2 and T3 than T1. A reduction (P less than 0.05) in lipid peroxidation activity (LPO) in fresh and frozen semen in T3 group was observed. It may be concluded that dietary supplementation of Mn @ 30 ppm, Co @ 0.22 ppm and Cr @ 2 ppm, respectively per day per Sahiwal bull can improve the qualitative and quantitative attributes of semen.

Effect of Chelated and Inorganic Zinc, Selenium and Chromium on Antioxidant Status, Biochemical and Production Parameters in Broiler

In the present investigation we explore the use of organic and inorganic zinc, selenium and chromium to modulate antioxidant defense system, biochemical status and enhance production response of Broiler. Total 312 day old Cobb broiler chicks were used in the experiment. The results indicate that mean plasma superoxide dismutase, glutathione peroxidise and glucose concentration were non-significantly different in all groups. Significantly (p less than 0.05) higher mean plasma catalase concentration and TBA value was found in T13 and control group respectively. Mean plasma total protein, albumin and globulin were significantly (p less than 0.01) higher in organic Zn, Se and Cr (T13) followed by organic Cr (T10) supplemented group. Mean body weight gain, feed intake, FER and PI were significantly (p less than 0.01) higher in organic Zn, Se and Cr (T13) followed by organic Se (T7) supplemented group. In the present investigation organic Zn, Se and Cr supplementation showed systemic effects with a better biochemical status, which could be translated into better production performance and lower mortality.

Age-Dependent Decline in Cardiac Function in Guanidinoacetate-N-Methyltransferase Knockout Mice.

AimGuanidinoacetate N-methyltransferase (GAMT) is the second essential enzyme in creatine (Cr) biosynthesis. Short-term Cr deficiency is metabolically well tolerated as GAMT–/– mice exhibit normal exercise capacity and response to ischemic heart failure. However, we hypothesized long-term consequences of Cr deficiency and/or accumulation of the Cr precursor guanidinoacetate (GA).MethodsCardiac function and metabolic profile were studied in GAMT–/– mice >1 year.ResultsIn vivo LV catheterization revealed lower heart rate and developed pressure in aging GAMT–/– but normal lung weight and survival versus age-matched controls. Electron microscopy indicated reduced mitochondrial volume density in GAMT–/– hearts (P < 0.001), corroborated by lower mtDNA copy number (P < 0.004), and citrate synthase activity (P < 0.05), however, without impaired mitochondrial respiration. Furthermore, myocardial energy stores and key ATP homeostatic enzymes were barely altered, while pathology was unrelated to oxidative stress since superoxide production and protein carbonylation were unaffected. Gene expression of PGC-1α was 2.5-fold higher in GAMT–/– hearts while downstream genes were not activated, implicating a dysfunction in mitochondrial biogenesis signaling. This was normalized by 10 days of dietary Cr supplementation, as were all in vivo functional parameters, however, it was not possible to differentiate whether relief from Cr deficiency or GA toxicity was causative.ConclusionLong-term Cr deficiency in GAMT–/– mice reduces mitochondrial volume without affecting respiratory function, most likely due to impaired biogenesis. This is associated with hemodynamic changes without evidence of heart failure, which may represent an acceptable functional compromise in return for reduced energy demand in aging mice.

Dietary supplemental chromium and niacin influence the growth performance and fat deposition in lambs

Context Nowadays fat is an unpopular constituent of meat for consumers and therefore, a decrease in fat-tail size is often desirable for producers. Feed additives like chromium (Cr) and niacin (B3) have been reported to improve meat quality in beef and dairy cattle. However, their effect on meat quality and performance of fat-tail breeds of finishing lambs is unknown. Aim The aim of this study was to investigate the effect of supplemental chromium (Cr) and niacin (B3) on performance and fat deposition of carcass of finishing lambs. Methods Twenty male Zandi lambs (23.7 ± 0.73 kg) were allocated into one of four treatments: (1) control; (2) 300 µg/ kg DM Cr as chromium methionine; (3) 200 mg/kg DM B3 as rumen-protected niacin; and (4) 300 µg/ kg DM Cr as chromium methionine + 200 mg/kg DM B3 as rumen-protected niacin. Key results Chromium and B3 supplementation decreased blood glucose, insulin, triglycerides and low-density lipoprotein levels (P &amp;lt; 0.05). Lambs fed diet supplemented with B3 consumed more feed with a higher growth (P &amp;lt; 0.05) compared with other groups. There were no significant differences in feed efficiency, hot carcass weight, and dressing percentage among experimental groups. However, there was a decrease in the subcutaneous, abdominal, tail and total carcass fat in Cr supplemented lambs (P &amp;lt; 0.01) compared with other experimental groups. The expression level of acetyl CoA carboxylase 1 (ACC1) and diglyceride acyltransferase 2 (DGAT2) genes was lower in Cr groups of lambs compared with other groups (P &amp;lt; 0.05). Conclusions These results indicated that organic Cr supplementation improved meat quality by reducing fat accumulation, whereas B3 supplementation resulted in higher growth rate and feed intake. Implications Results showed that chromium supplementation reduces expression level of acetyl CoA carboxylase 1 and diglyceride acyltransferase 2 genes resulting in lower level of subcutaneous, abdominal, tail and total carcass fat of finishing lambs.

Semen Creatine and Creatine Kinase Activity as an Indicator of Sperm Quality.

The role of creatine (Cr) and creatine kinase (CK) in sperm function remains unclear. The study aimed to assess Cr and CK in seminal plasma and test their association with sperm characteristics. The study included 62 males with couple's infertility and 26 males who have already fathered children. Semen Cr and CK were assessed by GC-MS and spectrophotometry, respectively. Seminogram parameters were analyzed using conventional methods. Cytomorphologic analysis of sperm showed normozoospermia in 53 men (NS) and an asthenozoospermia (AS) in 35 men. Semen Cr was high with no significant difference between the two groups (791 ± 342 and 744 ± 422 µmol/L, respectively). However, semen CK activity was higher in AS group (1,360 ± 1,050 vs. 830 ± 580 U/L, p = 0.013). Semen Cr was positively related to progressive motility (r = 0.284; p = 0.010). Semen CK was negatively correlated with sperm concentration (r = -0.29; p = 0.01), progressive motility (r = -0.26; p = 0.03), and the percentage of abnormal spermatozoa (r = -0.28; p = 0.02). Semen contains high amounts of Cr and increased CK activity. Low semen Cr is associated with reduced sperm motility while high CK activity is associated with poor sperm quality. The findings suggest that Cr is of importance for sperm metabolism and that Cr supplementation could be useful in males with poor quality sperm.

Chromium Differentially Affects Hydrogen Peroxide Distribution in Primary and Adventitious Roots of Arabidopsis thaliana L.

The post-embryonic growth of the Arabidopsis thaliana root system can be modified by different types of stress, such as sublethal concentrations of metals, which may induce the production of reactive oxygen species (ROS). In this study, the effects of different concentrations of potassium chromate (K₂CrO4) on the distribution and relative quantity of hydrogen peroxide (H2O2) were determined in primary and adventitious roots in A. thaliana HyPer line seedlings. This line has a biosensor that specifically reports H2O2 levels within tissues as fluorescence. Primary root growth was inhibited at 100 μM Cr (VI); in contrast, adventitious root formation was induced over the main root growth axis. These structures proliferated from 100-160 μM Cr (VI), and much higher concentrations (180-200 μM) of K₂CrO4 were required to affect their growth. The H2O2 distributions were observed in the columella and lateral root cap of primary roots of plants grown in medium lacking dichromate, but following the development of toxicity symptoms, H2O2 changed its distribution to the meristem and differentiation zones. Conversely, adventitious roots had comparable H2O2 distribution patterns in untreated plants and those exposed to Cr (VI) supplementation. Thus, differential H2O2 distribution correlates with the resistance of adventitious roots, but not primary roots, to dichromate and underlies cell reorganization at the apex to support growth.

Muscle phenotype of AGAT- and GAMT-deficient mice after simvastatin exposure.

Statin-induced myopathy affects more than 10 million people worldwide. But discontinuation of statin treatment increases mortality and cardiovascular events. Recently, L-arginine:glycine amidinotransferase (AGAT) gene was associated with statin-induced myopathy in two populations, but the causal link is still unclear. AGAT is responsible for the synthesis of L-homoarginine (hArg) and guanidinoacetate (GAA). GAA is further methylated to creatine (Cr) by guanidinoacetate methyltransferase (GAMT). In cerebrovascular patients treated with statin, lower hArg and GAA plasma concentrations were found than in non-statin patients, indicating suppressed AGAT expression and/or activity (n = 272, P = 0.033 and P = 0.039, respectively). This observation suggests that statin-induced myopathy may be associated with AGAT expression and/or activity in muscle cells. To address this, we studied simvastatin-induced myopathy in AGAT- and GAMT-deficient mice. We found that simvastatin induced muscle damage and reduced AGAT expression in wildtype mice (myocyte diameter: 34.1 ± 1.3µm vs 21.5 ± 1.3µm, P = 0.026; AGAT expression: 1.0 ± 0.3 vs 0.48 ± 0.05, P = 0.017). Increasing AGAT expression levels of transgenic mouse models resulted in rising plasma levels of hArg and GAA (P < 0.01 and P < 0.001, respectively). Simvastatin-induced motor impairment was exacerbated in AGAT-deficient mice compared with AGAT-overexpressing GAMT-/- mice and therefore revealed an effect independent of Cr. But Cr supplementation itself improved muscle strength independent of AGAT expression (normalized grip strength:55.8 ± 2.9% vs 72.5% ± 3.0%, P < 0.01). Homoarginine supplementation did not affect statin-induced myopathy in AGAT-deficient mice. Our results from clinical and animal studies suggest that AGAT expression/activity and its product Cr influence statin-induced myopathy independent of each other. The interplay between simvastatin treatment, AGAT expression and activity, and Cr seems to be complex. Further clinical pharmacological studies are needed to elucidate the underlying mechanism(s) and to evaluate whether supplementation with Cr, or possibly GAA, in patients under statin medication may reduce the risk of muscular side effects.

Effects of chromium supplementation on body composition, human and animal health, and insulin and glucose metabolism.

Chromium(III) has been proposed to have a nutritional or pharmacological role in changing body composition and improving symptoms of insulin resistance, type 2 diabetes, and related conditions although the mode of action of Cr(III) at a molecular level has failed to be elucidated. This review details the current status of studies into Cr(III) supplementation. Clinical trials, meta-analyses and systematic reviews have failed to demonstrate clinically significant effects from Cr(III) supplementation on body composition or symptoms of insulin resistance and related conditions in humans and farm animals. Although new Cr(III) supplements continue to appear in the scientific literature, studies have failed to elucidate the mechanism of chromium action at a molecular level. Conflicting results on a role of transferrin in Cr(III) transport and detoxification have appeared. Cr(III) supplementation cannot currently be recommended in humans or farm animals. Further studies are required to probe the mechanism of Cr(III) action in increasing insulin sensitivity and glucose uptake in rodent models of insulin resistance and diabetes, with particular attention being turned to a potential role of transferrin in Cr(III) transport and detoxification.

CHROMNIUM PICLONAT EFFECTS IN DIET OF MALE RABBITS EXPOSED TO HEAT STRESS ON SOME PRODUCTIVE TRAITS AND BLOOD SERUM PARAMETERS

current study was conducted to determine the effects of Chromium piclonat supplementation on some productive traits and serum parameters of male rabbit exposed to heat stress by used electric heaters ,twenty four male rabbits were randomly divided into four groups 6 for each, first group put in normal suitable climate condition based diet without additional Chromium and kept as positive control group , while The other three groups exposed to heat stress , the basal diet was consisted of 0, 300 , and 500 ppb of Chromium piclonate respectively as a feed additives . All rabbit received feed and water ad libitum, the results showed that there were Increasing organic Cr supplementation 300 and 500 pbb of two treated groups resulted in an increase in body weight compared with negative and positive control group , the serum glucose and cortisone hormone concentrations of both treated groups were decrease, as dietary Cr level increased (P&lt;0.05), but Cr supplementation did not affect total protein, albumen and globulin. These data indicated that organic Cr supplementation increased some performance traits, particularly body weight production and decreased in glucose and cortisone hormone while there were not significant effect in the total of serum protein, Albumin and globulin ,it can be concluded that adding chromium piclonat in dose 300,500pbb in diet of rabbits during hot periods has a benefits to overcome deterioration in some performance traits related to oxidative stress results from heat stress.

Grain source and chromium supplementation: Effects on health, metabolic status, and glucose-insulin kinetics in Holstein heifer calves

Carbohydrate-rich diets may increase urinary excretion of chromium (Cr) and the need to supplement the diet with Cr to meet animal requirements. The present study was performed to examine the effect of the type of grain (corn vs. barley) and Cr-methionine supplementation on health-related variables, blood levels of metabolites and hormones related to energy metabolism, and insulin sensitivity in Holstein calves. Forty-eight newborn heifers (3 d of age) were assigned randomly to 4 diets in a 2 × 2 factorial arrangement. Experimental diets were either corn-based (CBD) or barley-based (BBD) diets supplemented with 0 or 0.05 mg/kg of metabolic body weight. Chromium was provided in milk before weaning (d 3-73 of age) and in prewarmed water after weaning (d 74-94 of age). There was no interaction between the type of grain and Cr on the health-related variables and blood metabolites and hormones. Type of grain did not affect fecal score, respiration rate, and rectal temperature; however, there were tendencies for higher diarrhea occurrence (odds ratio = 1.69) and lower chance of having pneumonia (odds ratio = 0.49) in calves fed BBD versus CBD despite longer duration of diarrhea (0.54 d) and shorter days with pneumonia (0.63 d) in calves fed BBD. Calves supplemented with Cr had lower fecal score during the preweaning and overall periods and respiration rate throughout the study. Supplemental Cr decreased the duration (0.63 d) and chance of having pneumonia (odds ratio = 2.01). Calves fed BBD had lower blood levels of urea N during the postweaning period, with no changes in other blood variables between CBD and BBD. Tendencies were detected for lower blood levels of β-hydroxybutyric acid during the preweaning and overall periods and higher cortisol in Cr-supplemented calves. Chromium supplementation increased insulin clearance rate and decreased the time to half-maximal concentration and the area under the curve in BBD but not CBD calves. The calves were generally healthy, and the type of grain did not affect the health and blood variables related to energy metabolism. However, Cr supplementation increased fecal consistency, decreased respiration rate and days with pneumonia, and increased insulin sensitivity when added to BBD.