In vivo effects of high dietary copper levels on hepatocellular mitochondrial respiration and electron transport chain enzymes in broilers

The expression of cuproptosis-related genes in hepatocellular carcinoma and their relationships with prognosis

Background

The mechanism of cuproptosis has recently been reported in lipoylated proteins of the tricarboxylic acid (TCA) cycle. Besides, the role of copper was previously recognized in cancer progression. We evaluated the prognostic value of cuproptosis-related gene expression in hepatocellular carcinoma (HCC).

Methods

Remarkable genes were selected both in differential expression analysis and Kaplan-Meier survival analysis from ninety-six cuproptosis-related genes using The Cancer Genome Atlas (TCGA) database. The relationships between clinical characteristics and gene expression were performed with Wilcoxon signed-rank test, Kruskal-Wallis test, and logistic regression. Clinicopathologic factors correlated with overall survival in HCCs conducting univariate and multivariate Cox regression analysis. Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and Human Protein Atlas (HPA) databases were utilized to verify the results. Furthermore, Gene Set Enrichment Analysis (GSEA) identified the potential key pathways that dominate cuproptosis in HCC.

Results

Elevated ATP7A, SLC25A3, SCO2, COA6, TMEM199, ATP6AP1, LIPT1, DLAT, PDHA1, MTF1, ACP1, FDX2, NUBP2, CIAPIN1, ISCA2 and NDOR1 expression, as well as declined AOC1, FDX1, MT-CO1, and ACO1 expression were significantly emerged in HCC tumor tissues and were significantly associated with HCCs poor survival. The expressions of screened cuproptosis-related genes were prominently related to clinical features. GSEA analysis reported many key signaling pathways (such as natural killer cell mediated cytotoxicity, TCA cycle, glutathione metabolism, ATP-binding cassette (ABC) transporters, Notch signaling pathway, ErbB signaling pathway, and metabolism of xenobiotics by cytochrome p450) were differentially enriched in HCCs with varying degrees of cuproptosis-related genes expression.

Conclusions

The twenty cuproptosis-related genes might be utilized as new candidate prognostic biomarkers for HCC.

Accumulation and Enrichment of Trace Elements by Yeast Cells and Their Applications: A Critical Review

Maintaining the homeostasis balance of trace elements is crucial for the health of organisms. Human health is threatened by diseases caused by a lack of trace elements. Saccharomyces cerevisiae has a wide and close relationship with human daily life and industrial applications. It can not only be used as fermentation products and single-cell proteins, but also as a trace elements supplement that is widely used in food, feed, and medicine. Trace-element-enriched yeast, viz., chromium-, iron-, zinc-, and selenium-enriched yeast, as an impactful microelements supplement, is more efficient, more environmentally friendly, and safer than its inorganic and organic counterparts. Over the last few decades, genetic engineering has been developing large-scaled genetic re-design and reconstruction in yeast. It is hoped that engineered yeast will include a higher concentration of trace elements. In this review, we compare the common supplement forms of several key trace elements. The mechanisms of detoxification and transport of trace elements in yeast are also reviewed thoroughly. Moreover, genes involved in the transport and detoxification of trace elements are summarized. A feasible way of metabolic engineering transformation of S. cerevisiae to produce trace-element-enriched yeast is examined. In addition, the economy, safety, and environmental protection of the engineered yeast are explored, and the future research direction of yeast enriched in trace elements is discussed.

Enhancement of Intracellular Accumulation of Copper by Biogenesis of Lipid Droplets in Saccharomyces cerevisiae Revealed by Transcriptomic Analysis

Copper is an essential micronutrient for life, whose homeostasis is rigorously regulated to meet the demands of normal biological processes and to minimize the potential toxicity. Copper enriched by yeast is regarded as a safe and bioavailable form of copper supplements. Here, a Saccharomyces cerevisiae mutant strain H247 with expanded storage capability of copper was obtained through atmospheric and room-temperature plasma treatment. Transcriptomic analyses found that transcriptional upregulation of DGA1 might be the major contributor to the enhancement of intracellular copper accumulation in strain H247. The positive correlation between biogenesis of lipid droplets and intracellular accumulation of copper was confirmed by overexpression of the diacylglycerol acyltransferase encoding genes DGA1 and LRO1 or knockout of DGA1. Lipid droplets are not only the storage pool of copper but might prompt the copper trafficking to mitochondria, vacuoles, and Golgi apparatus. These results provide new insights into the sophisticated copper homeostatic mechanisms and the biological functions of lipid droplets.

Copper Induces Apoptosis Through Endoplasmic Reticulum Stress in Skeletal Muscle of Broilers

The purpose of this research was to investigate whether copper (Cu) exposure could induce apoptosis via endoplasmic reticulum stress (ERS) in skeletal muscle of broilers. A total of 240 one-day-old chickens were randomly divided into four groups by free access; the diets are as follows: control diet (Cu 11 mg/kg, control group) and high level of Cu diets (Cu 110 mg/kg, group I; Cu 220 mg/kg, group II; Cu 330 mg/kg, group III). The skeletal muscle tissues were collected on day 49 for further examination. The content of Cu, histopathology, and the expression levels of the genes and proteins related to ERS and apoptosis were detected. Results showed that the Cu levels in skeletal muscle were increased in a dose-dependent manner. Meanwhile, the spaces between the muscle fibers were wider with the increase of Cu content, and the myolysis was observed in group III. Besides, the mRNA expression levels of GRP78, GRP94, eIF2α, ATF6, XBP1, CHOP, Caspase-12, and Caspase3 were markedly increased in treated groups compared with control group, and the protein expression levels of GRP78, Caspase3, Active-Caspase3 and JNK were significantly elevated with the increase of dietary Cu. In summary, these findings suggested that Cu could induce apoptosis through ERS in skeletal muscle of broilers.

High dietary copper induces oxidative stress and leads to decreased egg quality and reproductive performance of Chinese Yellow broiler breeder hens

The objective of this study was to investigate the effects of dietary copper (Cu) on production, egg quality, and hatchability of Chinese Yellow broiler breeder hens and growth performance of their offspring. A total of 576 30-week-old hens were randomly allotted into 6 groups, each with 6 replicates (8 cages for each replicate with 2 birds per cage). The basal diet contained 3.50 mg/kg Cu, and the other 5 treatment diets contained 8.5, 13.5, 23.5 43.5, and 83.5 mg/kg Cu, respectively, additionally supplemented with Cu on the basal diet. The trial lasted for 15 wk. Qualified egg rate of birds fed 23.5 or 83.5 mg/kg Cu was significantly decreased (P < 0.05) compared with those given 3.5, 8.5, or 13.5 mg/kg Cu. Plasma malondialdehyde concentration showed quadratic effect (P = 0.002) which that decreased first then increased with dietary Cu increased. Highest values of Cu content and hepatic activity of Cu-ATPase occurred in hens fed 83.5 mg/kg dietary Cu with linear (P = 0.001) and quadratic (P = 0.001) effects. Shell strength and proportion on 18th day of live embryos of hens fed 13.5 mg/kg Cu were the greatest compared with other groups respectively (P < 0.05); rate of qualified eggs for hatch and hatchability of fertilized eggs of hens fed 83.5 mg/kg Cu were the least (P < 0.05). In conclusion, both inadequate (3.5 mg/kg diet) and excess (83.5 mg/kg) of dietary Cu can induce oxidative stress in hens and lead to decreased egg quality. Hatchability and growth performance of offspring were decreased when breeder hens were fed excess Cu in spite of greater hatching weight. The appropriate dietary Cu level for Chinese Yellow broiler breeder hens during the egg-laying period is 15.7 to 21.2 mg/kg (1.81-2.44 mg Cu fed per day) when based on Cu level and Cu-ATPase activity in the liver. This dietary Cu requirement is approximately doubled (∼40 mg/kg, ∼4.60 mg Cu per bird per day) for maximal response of eggshell thickness.

Pb, Cd, and Cu Play a Major Role in Health Risk from Contamination in Duck Meat and Offal for Food Production in Thailand

Zinc, Pb, Cd, Mn, Fe, Cr, and Cu levels in duck meat from large-scale farms have been found to be significantly higher than those from free-grazing duck farms. Zinc, Co, Mn, Cr, and Cu contamination levels in duck liver from large-scale farms were significantly higher than those from free-grazing farms; only Cd in duck liver from free-grazing farms was higher than in liver samples from large-scale farms at P < 0.05. Lead, Cd, Fe, and Cr levels in duck intestine samples from free-grazing farms were higher than large-scale farms at P < 0.001. Moreover, the average concentrations of Pb in duck meat and liver samples from large-scale farms and Cd levels in duck liver samples from free-grazing farm also exceeded the FAO/WHO and Codex Alimentarius limits by 100% (55/55), 100% (54/54), and 67.6% (23/34), respectively. PCA analysis showed a strong positive relationship between the eight metals in meat, liver, and intestine was > 0.69, > 0.69, and > 0.72, in order. The relationship of the liver combined with the intestine was > 0.65. This study indicated that consumers may incur health risks from long-term consumption of duck due to high Pb and Cd concentrations from both types of farms, particularly from large-scale duck farms.

Effect of Different Levels and Sources of Dietary Copper, Zinc and Manganese on the Performance and Immune and Redox Status of Turkeys

The aim of the study was to determine the effectiveness of the combined use of Cu, Zn, and Mn nanoparticles in the diet of turkeys with regard to potential reduction of the levels of these elements added to feed. The experiment was carried out on turkeys' hens assigned to four groups. Turkeys from the PC group received feed with the addition of inorganic forms of Cu, Zn, and Mn in the B.U.T. (British United Turkeys) recommended levels, from group IR received the addition in amounts reduced to 10% of the recommended levels, and from group NR received the addition of elements in the form of nanoparticles in the same amounts as in group IR. The turkeys from group NC received feed without the addition of these elements. The research showed that the addition of Cu, Zn, and Mn to turkey diets, in both inorganic forms and as nanoparticles, in quantities covering only 10% of B.U.T. recommendations had no adverse effect on growth performance or on the antioxidant and immune defense of turkeys. The changes in the redox status of the turkeys whose diet was not supplemented with Cu, Zn, and Mn indicate reduced oxidation processes in the tissues.

Arsenic trioxide and/or copper sulfate induced apoptosis and autophagy associated with oxidative stress and perturbation of mitochondrial dynamics in the thymus of Gallus gallus

Arsenic (As) and copper (Cu) are ubiquitous environmental contaminants that are hazardous to the immune system. Our objective was to investigate the toxicity and potential mechanisms of thymus exposure to As and/or Cu. A chicken model was established by adding arsenic trioxide (As₂O₃; 30 mg/kg), copper sulfate (CuSO₄; 300 mg/kg), and simultaneously both elements in the basal diet. After the chickens were fed for 12 weeks, a significant reduction in antioxidant enzyme levels or production of malondialdehyde (MDA) emphasized the occurrence of oxidative stress. Furthermore, an imbalance in mitochondrial dynamics along with its abnormal structure certified mitochondrial dysfunction. Additionally, elevated levels of pro-apoptotic and autophagy genes and decreased levels of antiapoptotic genes were found in treated groups. Karyopyknosis and chromatin peripheral condensation were accompanied by an increased apoptosis ratio, as well as accumulation of autophagosomes, thus indicating that apoptosis and autophagy are involved in immune cell death. All of the above thymus lesions and index abnormalities occurred in a time-dependent manner, and the Cu and As co-administered groups showed more deteriorating effects than the Cu and As groups alone. Moreover, in the As or Cu group, the thymus tissue suffered different susceptibilities in oxidative toxicity, which needs further study. Collectively, our results manifested that co-exposure to As and Cu increased the oxidative burden and exacerbated mitochondrial dysfunction on the thymus. Additionally, apoptosis and autophagy may act as partners in inducing cell death in a cooperative manner in chicken thymus after As and/or Cu exposure.

Copper requirements of broiler breeder hens

One-hundred-twenty Cobb 500 hens, 20 wk of age, were randomly allocated into individual cages with the objective of estimating Cu requirements. After being fed a Cu deficient diet for 4 wk, hens were fed diets with graded increments of supplemental Cu (0.0; 3.5; 7.0; 10.5; 14; and 17.5 ppm) from Cu sulfate (CuSO4 5H2O), totaling 2.67; 5.82; 9.38; 12.92; 16.83; and 20.19 ppm analyzed Cu in feeds for 20 weeks. Estimations of Cu requirements were done using exponential asymptotic (EA), broken line quadratic (BLQ), and quadratic polynomial (QP) models. Obtained Cu requirements for hen d egg production and total settable eggs per hen were 6.2, 7.3, and 12.9 ppm and 8.1, 9.0, and 13.4 ppm, respectively, using EA, BLQ, and QP models. The QP model was the only one having a fit for total eggs per hen with 13.1 ppm Cu as a requirement. Hemoglobin, hematocrit, and serum Cu from hens had requirements estimated as 13.9, 11.3, and 18.5, ppm; 14.6, 13.0, and 19.0 ppm; and 16.2, 14.6, and 14.2 ppm, respectively, for EA, BLQ, and QP models. Hatching chick hemoglobin was not affected by dietary Cu, whereas requirements estimated for hatching chick hematocrit and body weight and length were 10.2, 12.3, and 13.3 ppm using EA, BLQ, and QP models; and 6.8 and 7.1 ppm, and 12.9 and 13.9 ppm Cu using EA and BLQ models, respectively. Maximum responses for egg weight, yolk Cu content, and eggshell membrane thickness were 14.9, 12.7, and 15.1 ppm; 15.0, 16.3, and 15.7 ppm; and 7.3, 7.8, and 14.0 ppm Cu, respectively, for EA, BLQ, and QP models. Yolk and albumen percentage were adjusted only with the QP model and had requirements estimated at 11.0 ppm and 11.3 ppm, respectively, whereas eggshell mammillary layer was maximized with 10.6, 10.1, and 14.4 ppm Cu using EA, BLQ, and QP models, respectively. The average of all Cu requirement estimates obtained in the present study was 12.5 ppm Cu.

Alterations of antioxidant indexes and inflammatory cytokine expression aggravated hepatocellular apoptosis through mitochondrial and death receptor-dependent pathways in Gallus gallus exposed to arsenic and copper

In this study, we sought to investigate the effects of sub-chronic exposure of arsenic (As) and copper (Cu) on oxidative stress, inflammatory response, and mitochondria and death receptor apoptosis pathways in chicken liver. Seventy-two 1-day-old male Hy-line chickens were treated with basal diet, 30 mg/kg arsenic trioxide (As₂O₃), or/and 300 mg/kg copper sulfate (CuSO₄) for 4, 8, and 12 weeks. Study revealed that exposure to As or/and Cu undermined the antioxidant function and increased lipid peroxidation. Worse yet, liver cell swollen, vacuolar degeneration, and inflammatory cell infiltration were accompanied by an increase of the nuclear factor-κB (NF-κB) and its downstream inflammation-related genes after exposure to As or/and Cu. Furthermore, mitochondria swollen and chromatin condensation were found in As and Cu groups, and hepatocyte nuclear membrane rupture and markedly increased (P < 0.01) apoptosis index were observed in As combined with Cu group. Meanwhile, the transcription and protein expression levels of Bcl-2-associated X protein (Bax), p53, cytochrome c (Cyt c), and caspase-3, 8, 9 were upregulated and B cell lymphoma-2 (Bcl-2) was downregulated in As, Cu, and As + Cu groups in the liver tissues (P < 0.05, P < 0.01). Our results indicated that exposure to As or/and Cu could lead to oxidative stress, inflammatory response, and tissue damage and aggravate hepatocellular apoptosis through mitochondrial and death receptor-dependent pathways in chicken liver. And As and Cu showed a possible synergistic relationship in liver damage.

Effect of different levels of copper nanoparticles and copper sulphate on performance, metabolism and blood biochemical profiles in broiler chicken

A study was conducted to investigate the influence of copper administration in ovo to chicken embryos and/or supplied in drinking water to growing chickens in the form copper nanoparticles (Cu-NP) or copper sulphate (CuSO₄ ). The fertilised eggs were assigned to three groups (n = 50 per group): control (not injected), injected with 50 mg/kg Cu-NP or with 50 mg/kg CuSO₄ at day 1 of incubation. Thereafter, 126 one-day-old broiler chickens were randomly assigned to seven post-hatched groups: control not injected and not provided with Cu in the drinking water, injected with 50 mg/kg Cu-NP + 20 mg/kg in water, not injected + 20 mg/kg Cu-NP in water, injected with 50 mg/kg CuSO₄  + 20 mg/kg in water, not injected + 20 mg/kg CuSO₄ in water, injected with 50 mg/kg Cu-NP and injected with 50 mg/kg CuSO₄ . The experiment was carried out from day 1 to 35 post-hatching. The in ovo injection of Cu improved the final body weight, average daily gain and feed conversion ratio in relation to the control group. Conversely, the provision of Cu in the drinking water had less of an effect on growth performance in comparison with the injected groups. A significant improvement was shown in energy and nitrogen utilisation, being better for Cu-NP than CuSO₄ . The cholesterol, urea and glucose levels in the blood were reduced by Cu-NP treatment in relation to the other groups. The relative weight of the liver was decreased, while bursa of Fabricius was increased in Cu groups in relation to the control group. Cu excretion was only reduced in chickens injected with 50 mg/kg Cu-NP + 20 mg/kg in water. The immune-related genes were not affected by the treatments. The in ovo injection of Cu-NP might improve broiler performance more efficiently than the injection of CuSO₄ or the provision of Cu-NP and/or CuSO₄ in drinking water.

Ameliorative Effects of Dietary Selenium Against Cadmium Toxicity Is Related to Changes in Trace Elements in Chicken Kidneys

The ameliorative effects of selenium (Se) against cadmium (Cd)-induced toxicity have been reported extensively. However, few studies have assessed the effects of multiple ions simultaneously on the variations of elements. In this study, the changes in Se, Cd, and 26 other element concentrations were investigated in chicken kidneys. One hundred and twenty-eight 31-week-old laying hens were fed a diet supplemented with either Se, Cd, or both Se and Cd for 90 days. The ion content was analyzed by inductively coupled plasma mass spectrometry (ICP-MS). We found that the Se, Cd, and combined Se and Cd treatments significantly affected the trace elements in the chicken kidneys. The Cd supplement caused ion profile disorders, including reduced concentrations of V, Cr, Mn, Mo, As, Ba, Hg, Ti, and Pb and increased Si, Cu, Li, Cd, and Sb. The Se supplement reduced the contents of Co, Mo, and Pb and increased the contents of Cr, Fe, and Se. Moreover, Se also increased the concentrations of Cr, Mn, Zn, and Se and decreased those of Li and Pb, which in contrast were induced by Cd. Complex interactions between elements were analyzed, and both positive and negative correlations among these elements are presented. The present study indicated that Se can help against the negative effects of Cd and may be related to the homeostasis of the trace elements in chicken kidneys.