Bis-choline tetrathiomolybdate prevents copper-induced blood–brain barrier damage

In Wilson disease, excessive copper accumulates in patients’ livers and may, upon serum leakage, severely affect the brain according to current viewpoints. Present remedies aim at avoiding copper toxicity by chelation, for example, by D-penicillamine (DPA) or bis-choline tetrathiomolybdate (ALXN1840), the latter with a very high copper affinity. Hence, ALXN1840 may potentially avoid neurological deterioration that frequently occurs upon DPA treatment. As the etiology of such worsening is unclear, we reasoned that copper loosely bound to albumin, that is, mimicking a potential liver copper leakage into blood, may damage cells that constitute the blood-brain barrier, which was found to be the case in an in vitro model using primary porcine brain capillary endothelial cells. Such blood–brain barrier damage was avoided by ALXN1840, plausibly due to firm protein embedding of the chelator bound copper, but not by DPA. Mitochondrial protection was observed, a prerequisite for blood–brain barrier integrity. Thus, high-affinity copper chelators may minimize such deterioration in the treatment of neurologic Wilson disease.

Initial Liver Copper Status in Finishing Beef Steers Fed Three Dietary Concentrations of Copper Affects Beta Agonist Performance, Carcass Characteristics, Lipolysis Response, and Muscle Inflammation Markers

Ninety-three Angus-crossbred steers (470 ± 35 kg) were assigned to a 3 × 2 factorial to determine the effects of Cu status and beta agonist (BA) on performance, carcass characteristics, lipolytic rate, and muscle inflammation. Factors included Cu supplementation (mg Cu/kg dry matter (DM)) at: 0 (LO), 10 (MED), or 20 (HI) from Cu amino acid complex (Availa Cu; Zinpro) with no BA (NoRAC) or 300 mg·steer−1·day−1 of ractopamine hydrochloride (RAC; Optaflexx; Elanco) for final 28 days of 88-day trial. Linear and quadratic effects of Cu status within BA treatment were tested. Pre-BA gain was not affected by Cu supplementation (p ≥ 0.57), although day 53 liver Cu quadratically increased (p = 0.01). Average daily gain and muscle IL-8 gene expression quadratically increased (p ≤ 0.01), with MED having greatest gain and gene expression. Ribeye area tended to quadratically increase with Cu supplementation within RAC (p = 0.08). In vitro basal lipolytic rate tended to quadratically increase with Cu supplementation within RAC (p = 0.11), while stimulated lipolytic rate tended to linearly increase within NoRAC (p = 0.10). These data suggest lipolysis and the BA response of steers are influenced by dietary and liver Cu concentrations.

COPPER AND IRON SUPPLEMENTATION IN THE TROPICAL ENVIRONMENT EFFECTS ON HAEMATOLOGICAL MEASUREMENTS, ORGAN WEIGHTS, TISSUE COPPER AND IRON

The study which lasted 3 months was a factorial arrangement in which nine dietary treatments resulting from supplementation of a commercial layers diet with 0, 200 or 400 mg/kg Copper and 0, 100 or 200 mg/kg Iron were fed to 135 fifty two-week old laying hens of the Golden Hubbard Connect Strain. After 12 weeks on the diets, three birds, randomly selected from each treatment, were slaughtered and their blood, liver, spleen and heart analysed for effect of supplementary copper and iron on haemoglobin content, packed cell volume and weights of the liver, spleen and heart and their copper and iron concentrations. No significant effects of supplementary copper or Iron or their interaction were observed on haemoglobin, packed cell volume or weights of the liver, spleen and heart. However, dietary iron supplementation produced significant (P<0.05) effects on iron storage in the liver and spleen but not on copper storage. On the other hand, copper addition significantly (P<0.05) increased liver storage of copper and spleen storage of iron. Supplementary copper and iron Interaction effects which were not significant for all other measurements, were observed to be significant (P<0.05) for liver copper and Iron concentrations and spleen copper concentration and highly significant (P<0.01) for spleen iron concentration.

PSXII-10 The effects of different mineral supplementation strategies on feedlot performance of mineral deficient cattle

Mineral deficient cattle that enter a feedlot have been documented to have increased morbidity and mortality rates and decreased feedlot performance. The objective of this research was to explore current practices used by feedlot producers when receiving mineral deficient cattle. To accomplish this, forty steers were blocked by weight and mineral status, then assigned to one of four treatment groups: control (Con; n = 10), industry mineral requirements (IND; n = 10) top dressed on TMR fed, 2X industry mineral requirements (2XIND; n = 10) top dressed on TMR fed, and MultiMin® injection at labeled dose (MM; n = 10). All steers received the same ration in pens equipped with GrowSafe® bunks. Standing liver biopsies were collected on day 0, 5, 10, 20, 30 and 40 and analyzed for mineral content. Steers were weighed on day 0, 14, 28, 41, 56, 70, 84, and 110. Average daily gain (ADG), dry matter intake (DMI) and feed efficiency (FE) were recorded. After the trial, steers were harvested at a commercial facility and carcass data was obtained from the plant. There were no differences (P &gt; 0.05) in weight gain or overall ADG between treatment groups. When analyzed over time, treatment had an effect (P &lt; 0.001) on liver copper and selenium concentrations, but no effects (P &gt; 0.05) were observed on liver manganese and zinc concentrations. Additionally, when DMI was analyzed over time, effects (P &lt; 0.05) of time, treatment, and treatment*time were observed, and effects (P &lt; 0.05) of time and treatment*time were observed on FE. Treatment had no effect (P &gt; 0.05) on carcass data. These data indicate that different mineral supplementation strategies have diverse effects on feedlot performance and liver mineral concentrations over time.

Assessment of copper accumulation in archived liver specimens from cats

Objectives The aim of this study was to assess hepatic copper concentrations and zonal distribution in cat liver specimens. Methods For this study, 121 archived, formalin-fixed, paraffin-embedded liver specimens from cats were used. Tissue sections were stained for copper with rhodanine and scored from 0 (no copper accumulation) to 5 (panlobular copper accumulation). The tissue specimens were then deparaffinized and hepatic copper concentrations were measured using flame atomic absorption spectroscopy. Results Tissue samples were categorized into four groups based on histopathologic findings: (1) no significant histopathologic hepatic changes (n = 66); (2) hepatic steatosis (n = 18); (3) inflammatory or infectious disease (n = 24); and (4) neoplasia (n = 13). Of the 121 specimens, 13 (11%) stained positive for copper, with three having a score ⩾3. Thirty-seven specimens (31%) had copper concentrations above the reference interval ([RI] <180 µg/g dry weight liver). Copper concentrations in cats with hepatic inflammatory or infectious disease were significantly higher than cats with hepatic steatosis ( P = 0.03). Copper-staining score and concentration were positively correlated ( rs = 0.46, P <0.001). Conclusions and relevance Despite the fact that 31% of specimens had copper concentrations above the RI, only 11% showed positive copper staining and only 2.5% had a score ⩾3. Our findings suggest that hepatic copper concentrations greater than the upper limit of the RI are relatively common in cats. Further studies to determine the factors that influence hepatic copper staining in cats and to establish contemporary RIs for hepatic copper in healthy cats are warranted.

Influence of a mineral supplement containing calcium, phosphorus and micronutrients on intake, digestibility, performance and mineral status of young Nellore bulls in a feedlot

We measured nutrient intake and digestibility, performance and mineral status of young Nellore bulls fed three diets with and without supplementation comprising calcium (Ca), phosphorus (P) and micro-minerals during the growing and finishing phases. Five bulls were slaughtered at the beginning of the experiment to measure initial mineral status. Forty-two young Nellore bulls (initial bodyweight (mean ± s.d.) 270.4 ± 36.6 kg, age 8 months) were assigned for 125 days to one of six treatments: sugarcane as a roughage source plus a concentrate based on soybean meal and soybean hull with (SH100) and without (SH0) supplementation; sugarcane as a roughage source plus a concentrate based on soybean meal and ground maize with (SC100) and without (SC0) supplementation; and maize silage as a roughage source plus a concentrate based on soybean meal and maize with (CS100) and without (CS0) supplementation. The experiment was conducted as a completely randomised design with a 3 × 2 factorial arrangement of treatments. Nutrient intake and digestibility, bone and serum parameters related to Ca and P metabolism, and liver mineral concentrations were measured. Nutrient intake, digestibility and performance were not affected (P &gt; 0.10) by the mineral factor. Water intake was higher (P &lt; 0.05) with SH100 than with all other diets. Rib-bone breaking strength and density according to dual-energy X-ray absorptiometry were reduced (P &lt; 0.04) in the absence of supplementation. Metatarsus parameters were not affected (P &gt; 0.10). Liver copper (Cu) content was reduced (P &lt; 0.01) in diets without supplementation. In conclusion, the short-term absence of mineral supplementation did not influence intake and digestibility. However, depending on diet type, absence of Cu may reduce the hepatic Cu content, and a low Ca:P ratio may stimulate bone reabsorption without compromising performance. Therefore, under our conditions, mineral requirements are overestimated by nutritional systems.

Oxidative stress and neurobehavioural changes in rats following copper exposure and their response to MiADMSA and d-penicillamine

An increase in copper concentration in body may lead to hepatolenticular degeneration which is considered as one clinical feature of Wilson’s disease. Chelation therapy using d-penicillamine is the preferred medical treatment for reducing the toxic effects of copper. However, a few shortcomings associated with d-penicillamine led us to search of an alternative antidote for copper toxicity. Monoisoamyl-2, 3-dimercaptosuccinic acid (MiADMSA), a potent arsenic chelator under clinical trial, has been reported to reduce system copper level. Thus, the present study was envisaged to explore the ameliorative effect of MiADMSA against copper toxicity. Copper pre-exposed animals (CuSO4.5H2O; 100 mg/kg; p.o., for 6 weeks) were segregated in different groups and were administered equimolar dose (0.3 mEq/kg/day; p.o.) of d-penicillamine and MiADMSA for 5 days. The effect of different treatments on spontaneous locomotor activity, muscle coordination, depression like behaviour and contextual fear memory was analysed using neurobehavioural battery test. Biochemical variables related to oxidative stress, zinc and copper concentration were determined in liver, kidney and brain. The results suggested that copper exposure led to oxidative stress in liver, kidney and blood, along with moderate effects in brain. Treatment with d-penicillamine and MiADMSA reduced liver copper load. MiADMSA produced more pronounced beneficial effect compared to d-penicillamine by increasing brain GPx activity. Our study suggests that MiADMSA might be equally effective as d-penicillamine in depleting body copper load. More detailed studies using different doses are required to suggest whether MiADMSA could be an alternative for d-penicillamine in reducing oxidative injury, neurobehavioural changes and depleting body copper burden.