Nano-chromium picolinate and heat stress enhance insulin sensitivity in cross-bred sheep.

This study evaluated the effects of heat stress (HS) and dietary nano chromium picolinate (nCrPic) on metabolic responses of sheep to an intravenous glucose tolerance test (IVGTT), an intravenous insulin tolerance test (ITT) and an intramuscular adrenocorticotropin hormone (ACTH) challenge in sheep. Thirty-six sheep housed in metabolic cages were randomly allocated within 3 dietary groups (0, 400 and 800 µg/kg supplemental nCrPic) to either thermoneutral (22 °C) or cyclic HS (22 to 40 °C) conditions for 3 wk. Basal plasma glucose tended to be increased during HS (P = 0.052) and decreased by dietary nCrPic (P = 0.013) while plasma non-esterified fatty acid concentrations were decreased (P = 0.010) by HS. Dietary nCrPic reduced the plasma glucose area under the curve (P = 0.012) while there were no significant effects of HS on plasma glucose area under the curve in response to the IVGTT. The plasma insulin response over the first 60 min after the IVGTT was decreased by HS (P = 0.013) and dietary nCrPic (P = 0.022) with the effects being additive. In response to the ITT plasma glucose reached a nadir sooner (P = 0.005) in sheep exposed to HS, although there was no effect on the depth of the nadir. Dietary nCrPic decreased (P = 0.007) the plasma glucose nadir after ITT. Over the duration of the ITT plasma insulin concentrations were lower in sheep exposed to HS (P = 0.013) whereas there was no significant effect of supplemental nCrPic. There was no effect of either HS or nCrPic on cortisol response to ACTH. Dietary nCrPic supplementation decreased (P = 0.013) mitogen-activated protein kinase-8 (JNK) and increased (P = 0.050) carnitine palmitoyltransferase 1B (CPT1B) mRNA expression in skeletal muscle. Results of this experiment demonstrated that animals under HS and supplemented with nCrPic had greater insulin sensitivity.

Dietary nano chromium picolinate can ameliorate some of the impacts of heat stress in cross-bred sheep.

Two studies were conducted to evaluate the effect of nano chromium picolinate (nCrPic) during heat stress (HS) in sheep. In the initial study, 36 Merino × Poll cross-bred sheep were individually penned and allocated to 3 dietary treatments (0, 400 and 800 µg/kg nCrPic) for 8 wk. Body composition was determined at the beginning and end of the experiment using dual energy X-ray absorptiometry. The sheep remained in their dietary groups but were then placed in metabolic cages and randomly allocated within the dietary group to differing ambient temperature regimes, i.e., thermo-neutral (TN) (n = 18) and HS (n = 18), for 3 wk. Dietary nCrPic had no effect on growth performance and body composition during the initial study conducted under TN conditions. Heat stress decreased average daily feed intake (ADFI) (P = 0.002) whereas sheep under HS had reduced average daily gain (ADG) and indeed lost weight (P < 0.001). Dietary nCrPic increased both ADFI (P = 0.041) and ADG (P = 0.049) under both TH and HS conditions such that the performance of sheep receiving supplemental nCrPic and exposed to HS was similar to that of control sheep maintained under TN conditions. Heat stress increased rectal temperature (P < 0.001) and respiration rate (P < 0.001), particularly during the hottest parts of the day as indicated by interactions (P < 0.001) between time of day and thermal treatment. Rectal temperature was lower in sheep fed nCrPic (P = 0.050), particularly under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and time of day (P < 0.001) and dietary nCrPic, thermal treatment and time of day (P = 0.010). Similarly, respiration rate was lower in sheep fed nCrPic under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and thermal treatment (P < 0.001) and dietary nCrPic and time of day (P = 0.030). In conclusion, dietary nCrPic can partially ameliorate the negative effects of HS as indicated by the maintenance of ADFI and decreased physiological responses, such as elevations in rectal temperature and respiration rate.

Nano Chromium Picolinate Improves Gene Expression Associated with Insulin Signaling in Porcine Skeletal Muscle and Adipose Tissue.

The aim of this study was to investigate the interactive effects of dietary nano chromium picolinate (nCrPic) and dietary fat on genes involved in insulin signaling in skeletal muscle and subcutaneous adipose tissue of pigs. Forty-eight gilts were stratified on body weight into four blocks of four pens of three pigs and then within each block each pen was randomly allocated to four treatment groups in a 2 × 2 factorial design. The respective factors were dietary fat (22 or 57 g/kg) and dietary nCrPic (0 or 400 ppb nCrPic) fed for six weeks. Skeletal muscle samples were collected from the Longissimus thoracis and subcutaneous adipose tissue collected from above this muscle. Dietary nCrPic increased adiponectin, uncoupling protein 3 (UCP3) and serine/threonine protein kinase (AKT) mRNA expression, whereas dietary fat decreased adiponectin and increased leptin, tumor necrosis factor-α (TNF-α), peroxisome proliferator-activated receptors γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) mRNA expression in adipose tissue. In skeletal muscle, dietary nCrPic increased phosphatidylinositol 3 kinase (PI3K), AKT, UCP3 and interleukin-15 (IL-15), as well as decreased suppressor of cytokine signaling 3 (SOCS3) mRNA expression. The improvement in insulin signaling and muscle mass and the reduction in carcass fatness by dietary nCrPic may be via decreased SOCS3 and increased UCP3 and IL-15 in skeletal muscle and increased adiponectin in subcutaneous adipose tissue.

Effects of nanosized zinc oxide and γ-polyglutamic acid on eggshell quality and serum parameters of aged laying hens.

In order to increase zinc (Zn) absorption and improve eggshell quality, diets for aged laying hens were supplemented with different Zn sources and the effects on egg production, eggshell quality and serum parameters were recorded. Seventy-five 64-week old brown layers were individually caged and randomly allotted to five treatment groups: an un-supplemented Control and four groups, where the following Zn sources were added to the diets, ZnO (group ZnO), Zn-methionine (group Zn-Met), nanosized ZnO (group nanoZnO) and γ-PGA-nano ZnO (group γ-PGA-nanoZnO). The Zn level was maintained at 80 mg/kg in the supplemented diet, while the Control group received Zn at 40 mg/kg diet. The results indicated that the average daily feed intake was highest in group nanoZnO (p < 0.05), whereas further performance parameters were not influenced by treatments. Eggshell thickness was increased in group γ-PGA-nanoZnO (p < 0.05). Zn content in eggshells and Zn concentration in serum were increased in groups Zn-Met, nanoZnO and γ-PGA-nanoZnO (p < 0.05). Serum ghrelin concentration was significantly elevated in all Zn-supplemented groups, but further increased in groups nanoZnO and γ-PGA-nanoZnO (p < 0.05). Carbonic anhydrase activity was highest in group γ-PGA-nanoZnO and lowest in group Zn-Met (p < 0.05). Compared to the Control and group ZnO, supplementation of γ-PGA-nanoZnO and nanoZnO increased serum IgG levels (p < 0.001). In conclusion, dietary supplementation of nanoZnO and γ-PGA-nanoZnO increased Zn content in eggshells, serum Zn concentration, ghrelin and IgG levels of aged layers when compared to regular ZnO. Compared to Zn-Met, the serum carbonic anhydrase activity and ghrelin levels were also increased. Thus, nanosized ZnO alone or mixed with γ-PGA has positive effects on the Zn status of aged layers.

Nanosize of zinc oxide and the effects on zinc digestibility, growth performances, immune response and serum parameters of weanling piglets.

The aim of this study was to investigate the effect of dietary supplementation of nanosize zinc on zinc digestibility, growth performances, immune response and serum parameters of weanling piglets. Ninety-six LYD weanling piglets were assigned to control, zinc oxide (ZnO), organic-Zn (Zn-methionine) and nanosize ZnO (nano-Zn) groups with four replicates. The zinc was at the 120 mg/kg level in the treatment group's diet, while the control group's was 80 mg/kg Zn. The experiment results indicated that the nano-Zn and organic-Zn groups had significantly higher Zn digestibility compared to the ZnO and control groups. For the immune response traits, the IgG level and goat red blood cells (GRBC) antibody titer were nano-Zn and organic-Zn>ZnO>control; in the phytohemagglutinin (PHA) challenge test result, nano-Zn>organic-Zn>ZnO>control; in regard to the γ-globulin level, nano-Zn and organic-Zn>ZnO and control, with significant difference between groups. In the serum parameters aspect, serum Zn concentration in nano-Zn and organic-Zn groups were higher than in the ZnO and control groups, serum growth hormone concentration was increased in the nano-Zn group than in the other groups. In conclusion, nanosize zinc oxide for dietary supplementation can increase zinc digestibility, serum growth hormone levels and carbonic anhydrase activity and enhance the immune response of weanling piglets.

Toxicity evaluation of chromium picolinate nanoparticles in vivo and in vitro in rat.

The toxicity of nanoCrpic is still not understood and needs further investigation. Thus, this study investigated the effect of chromium picolinate nanoparticles (nanoCrpic) on the toxicity in vivo and in vitro in rat. In the in vivo study, 36 rats (Wistar, 8-week-old) were randomly divided into the control group (fed basal diet), the low-dose (300 ppb, µg/kg), and high-dose (1,000 ppb) nanoCrpic groups. The trial was conducted for 2 months; at the final stage of the trial, the rats were sacrificed, liver and kidney were examined, and samples of tissues were taken for histological examination. Hepatocytes isolated from 10-week-old Wistar male rats were used for in vitro study to examine the degree of DNA damage following exposure to 0 and 0.294 mM of H(2)O(2) for 30 min. Incubation medium was supplemented with 0 (control), 100, and 300 ppb nanoCrpic. In vivo study indicated that no lesions of liver or kidney were detected in 300 and 1,000 ppb nanoCrpic fed rats. The in vitro study evaluated DNA damage according to the percentage and distance of the fragments migration and revealed that there was insignificant difference between the nanoCrpic and control groups (p > 0.05). This study indicated that nanoCrpic at 300-1,000 ppb in vivo and at 100-300 ppb in vitro showed no signs of toxicity to rats.

Effects of supplemental levels of bazhen on growth performances, serum traits, immunity, meat quality and antioxidant activity of taiwan country chickens.

One hundred and sixty Taiwan country chickens (d-old chicks) were randomly assigned into four groups with four replicates and equal sex. Basal diets were supplemented with 0, 0.5, 1 and 2% of Bazhen powder, a traditional Chinese herbal medicine complex. The study was conducted for 14 wks. Experimental results indicated that Bazhen supplement did not influence feed intake, body weight gain and feed:gain ratio. Compared with control group, the percentage of serum HDL (high-density lipoprotein) linearly increased (p<0.03) and that of VLDL+LDL (very low-density+low-density lipoprotein) linearly decreased (p<0.03) in Bazhen supplemented groups, that 2% Bazhen was significantly different with control group (p<0.05). Chickens fed diets containing 2% Bazhen displayed reduced (p<0.05) serum GOT (glutamic-oxaloacetic transaminase) levels. The IgG, γ-globulin levels and PHA (phytohemagglutinin) skin challenge results in 1% Bazhan supplemented group were higher (p<0.05) than in the control group, the SRBC (sheep red blood cell) and ND (newcastle disease) titers in Bazhen supplemented groups were linear higher (p<0.05) than in the control group. The liver catalase activity and the capacity of scavenging DPPH (α-α-diphenyl-ß-picrylhydrazyl) radical were linearly increased (p<0.03) in Bazhen supplemented groups, and the 1 and 2% groups were different from the control group (p<0.05). Liver TBARS (thiobarbituric acid-reactive substances) levels in all Bazhen supplemented groups and total glutathione level in the 2% group were reduced (p<0.05) compared to the control group and displayed a linear response (p<0.05). The TBA (thiobarbituric acid) and pH value of the breast muscle after 24 h post-mortem in the Bazhen supplemented groups was linear lower (p<0.05) than in the control group. Results from this study demonstrated that Bazhen supplement in chicken had several beneficial effects, including increased SRBC and ND titers, HDL and IgG, γ-globulin levels, PHA skin challenge result, decreased VLDL+LDL and GOT levels, and displayed antioxidation effects in serum and carcass meat parameters.

Effects of Chinese traditional herbal medicine complex supplementation on the growth performance, immunity and serum traits of pigs.

The purpose of this study was to investigate the effects of a traditional Chinese herbal medicine complex supplementation on the growth performance, immunity and serological traits of pigs, and the feasibility of its use as a substitute for antibiotics. Thirty-six weaned pigs LYD with average initial body weight of 10 ± 0.55 kg were randomly divided into three treatments with three replicates. These constituted the control, the antibiotics group (chlortetracycline 100 µg/kg, oxytetracycline 100 µg/kg), and 0.3% Chinese herbal medicine complex group (CHM). Experiment results indicated that the CHM group exhibited significantly increased average feed intake and peripheral blood CD3(+)CD8(+) T cell percentage as compared with those of the antibiotics group (P < 0.05). High-density lipoprotein (HDL) level was greater while low-density lipoprotein + very low-density lipoprotein (LDL + VLDL) level was lower in the CHM group than the control group (P < 0.05). The in vitro results indicated that peripheral blood mononuclear cells (PBMC) stimulated by Con-A produced a greater interleukin (IL)-6 level in the CHM group and IL-6 level stimulated by lipopolysaccharide was greater than the antibiotics groups (P < 0.05). Above all, this study has indicated that the addition of Chinese traditional herbal complex to pigs' diets has beneficial results.

Supplementary health benefits of soy aglycons of isoflavone by improvement of serum biochemical attributes, enhancement of liver antioxidative capacities and protection of vaginal epithelium of ovariectomized rats.

BACKGROUND: In the literature, supplement of soy aglycons of isoflavone as estrogen agonists in improvement of serum biochemical attributes, liver antioxidative capacities and vaginal epithelium protection has been meagerly investigated. In this study, ovariectomized (OVX) rats were used as an animal model to simulate post-menopausal status. Supplementary health benefits of soy aglycons of isoflavone (SAI) on improvement of growth and serum biochemical attributes, enhancement of liver antioxidation-related capacities and protection of vaginal epithelium of the OVX rats were assessed. METHODS: As an in vivo study, 30 OVX Sprague-Dawley rats were distributed into OVX (positive control), OVX/LSAI (low SAI group - supplemented with 0.0135% SAI being equivalent to 80 mg per day for a 60 Kg-human), and OVX/HSAI (high SAI group - supplemented with 0.027% SAI) and 10 rats with sham operation as negative control fed with basal diet. RESULTS: The average daily gain (ADG), feed intake and feed/gain ratio were higher for the OVX groups than the sham group (P < 0.05). Serum isoflavone concentrations of the OVX rats were increased by SAI supplementation. In comparison, significantly lower serum cholesterol and LDL (low-density lipoprotein) levels, and higher HDL (high-density lipoprotein) levels were detected for the rats of OVX/HSAI group (P < 0.05). SAI supplementation also increased iron chelating ability and decreased values of TBARS (thiobarbituric acid-reactive substance) (P < 0.05) of liver extracts. Liver catalase activity and total antioxidative activity (trolox equivalency) were enhanced by HSAI supplementation (P < 0.05). Decrease of vagina epithelial cellular linings of the OVX rats were noticeably improved by dietary supplementation with SAI. CONCLUSION: Diets supplemented with soy aglycons of isoflavone have conferred health benefits to the OVX rats, in comparison to the sham rats fed with basal diet, by detection of higher serum isoflavone concentrations, significantly lower contents of serum cholesterol and LDL, and higher contents of serum HDL, increased iron chelating ability, lower contents of TBARS (thiobarbituric acid-reactive substance) and enhanced catalase and total antioxidative (as trolox equivalency) activities of the liver extracts, and protection of the epithelial cellular linings of vagina in the former rather than in the latter. This evidences that estrogen-agonist chemoprevention of menopausal-related cardiovascular diseases, decreased liver antioxidative capacities and epithelial degeneration of vagina could be achieved by dietary supplementation with soy aglycons of isoflavone.

Effect of adding extracted hesperetin, naringenin and pectin on egg cholesterol, serum traits and antioxidant activity in laying hens.

In this study three feed additives (hesperetin, naringenin and pectin) for laying hens were investigated on their influence on the egg yolk cholesterol, serum traits and antioxidant activities in hens. Additives were extracted from citrus and grapefruit peels and contained 31.5% crude hesperetin, 39% crude naringenin and 60% galacturonic acid (pectin). Eighty 30-week-old Leghorn laying hens were randomly assigned to four groups and received, for two months, a control diet or diets with 0.05% hesperetin, 0.05% naringenin or 0.5% pectin. All additives reduced the egg yolk cholesterol level significantly. Feeding diets with added flavonoids (hesperetin and naringenin) increased the yolk weight and the ratio of yolk weight/egg weight and the blood serum superoxide dismutase (SOD) activity was elevated. Total antioxidation capacity, the level of thiobarbituric acid-reactive substances and superoxide scavenging capacity in the naringenin group were greater than in the control group. Supplemented flavonoids reduced the serum cholesterol level significantly, while serum triglyceride concentration in the naringenin and pectin groups was reduced. Addition of flavonoids resulted in an enhanced cholesterol level in excreta. The results of this study indicated that intake of hesperetin, naringenin and pectin extracted from citrus and grapefruit peel in laying hens diet, may exhibit positive effects.

Influence of soy aglycon isoflavones on bone-related traits and lens protein characteristics of ovariectomized rats and bioactivity performance of osteoprogenitor cells.

Health benefits of soy isoflavones have attracted the concern of the public and the interest of health-care professionals. In this study, two trials were conducted in characterizing bone-related traits and lens proteins as affected by supplementation of soy aglycon isoflavones (SAI). In trial 1, an in vivo study, 20 Sprague-Dawley rats were ovariectomized (OVX) and randomly distributed into OVX and OVX+SAI (135 mg of SAI/kg of feed; 8.33 mg/kg body weight; 2.5 mg/day) groups. Another group containing 10 rats with a sham operation was control (Sham). The experiment period was 3 months, and the rats were subjected to bone-related traits and lens protein characterization. In trial 2, an in vitro study, osteoprogenitor cells (UMR-106) were divided into SAI-supplemented (0.5 mg of SAI/mL of medium) and unsupplemented groups. Results of the in vivo study indicated that daily BW gains in the OVX and OVX+SAI groups were greater than that of the Sham group (p < 0.05). Bone ash and Ca contents of the Sham and OVX+SAI groups were higher than those of the OVX group (p < 0.05), while bone density, strength, and phosphorus contents among groups varied insignificantly (p > 0.05). When the lens proteins were extracted and analyzed with size-exclusion HPLC, the contents of beta- and gamma-crystallins were lowest in the OVX group and the protein solubility decrease could be recovered by dietary SAI supplementation (shown by OVX+SAI group). Based on Raman spectra of the isolated lens proteins, disulfide bonds were observed more in OVX lens than in the Sham and OVX+SAI lens. Results of in vitro study with osteoprogenitor cells revealed that cell viability, alkaline phosphatase activity, osteocalcin, and Ca contents of the SAI-supplemented group were higher than those of the unsupplemented group (p < 0.05). The likely potency to enhance bone and lens health by SAI supplementation is worth pointing out.