A co-opted endogenous retroviral envelope promotes cell survival by controlling SLC31A1/CTR1-mediated copper transport and homeostasis

Copper is a critical element for eukaryotic life, involved in numerous cellular functions and in redox balance but it can be toxic in excess. Therefore, tight regulation of copper acquisition and homeostasis is essential for cell physiology and survival. Here, we identified a unique mechanism for cell survival involving the regulation of copper homeostasis by an endogenous retroviral (ERV) envelope glycoprotein called Refrex1. We show that extracellular copper sensing by cells increased Refrex1 expression, which in turn regulated copper acquisition through interaction with the main copper transporter SLC31A1/CTR1. Downmodulation of Refrex1 resulted in intracellular copper accumulation leading to ROS production and subsequent apoptosis, which could be reverted by copper chelator treatment. Our results demonstrate that Refrex1 has been co-opted for its ability to regulate copper entry through CTR1 interaction in order to limit copper excess for a proper redox balance, and suggests that other ERV may have similar metabolic functions among vertebrates.

Grazing Sheep in Organic Vineyards: An On-Farm Study about Risk of Chronic Copper Poisoning

Many winegrowers and sheep breeders are interested in wintertime grazing in vineyards, as an agroecological alternative to mowing or herbicide spraying, and additional supply of forage. Still, strong concern is raised by the use of copper-based fungicides, particularly in organic vineyards, since copper is known to induce chronic toxicosis in sheep. We conducted an on-farm study with n = 12 1-year-old Merinos × Mourerous ewes grazing the cover vegetation of vineyard plots during wintertime, in order to check whether this agricultural practice might be harmful to sheep. Our results indicate that most copper found in the cover vegetation originates from fungicide spraying versus plant uptake from the soil, and that rain-induced washing-off and plant growth-triggered dilution of copper are crucial to reach close-to-safe grazing conditions. Furthermore, we found that while sheep remained globally healthy during the 2 months of the experimental period, the plasma activity of Glutamate Dehydrogenase increased by 17.3 ± 3.0 U/L upon vineyard grazing (p < 0.001), reflecting liver storage of copper. We also discovered that the dynamics of molybdenum in sheep plasma are strongly affected by exposure to copper, suggesting a possible adaptation mechanism. Overall, our results suggest that winter grazing of sheep in organic vineyards is reasonably safe, but that care should be taken about grazing period duration. More research should be conducted with respect to long-term copper accumulation, spring and summer grazing, and possible protective mechanisms against copper chronic poisoning.

Hybrid Grapes for a Sustainable Viticulture in South Italy: Parentage Diagram Analysis and Metal Assessment in a Homemade Wine of Chambourcin Cultivar

The aim of this work was to explore a more sustainable approach in the viticulture of Mediterranean countries that could derive from growing hybrid grape varieties inheriting tolerance/resistance characters from the wild vines utilized for their selection. Among the plethora of hybrid grapes developed in the last decades, some are able to produce high-quality wines whose flavor resembles European varieties, thus overcoming a typical limit of several old hybrids based on V. labrusca whose wine was characterized by a distinctive wild flavor. In this context, we examined some characteristics of Chambourcin, one of the most promising hybrid cultivars producing quality red wine and requiring much less phytosanitary interventions than European grapevine. In detail, the scope of this study included the investigation of the parentage diagram for this hybrid grape variety and the chemical analysis of a Chambourcin wine produced in South Italy. We filled the gaps corresponding to some of the Vitis ancestors participating in its complex pedigree by means of a literature analysis and a mathematical approach. We found high ancestry of V. vinifera (about 41%), followed by V. berlandieri (about 28%), V. rupestris (about 19%) and to a lesser extent other American wild vines. The significant content of V. berlandieri and V. rupestris genome in Chambourcin explains the considerable resistance of this variety to the two main pathogens affecting grapevines, i.e., downy mildew and powdery mildew. We then analyzed an organic Chambourcin wine produced in South Italy from grapes obtained without any phytosanitary treatment by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) in order to assess heavy metal content and found it comparable to other (red and rosè) V. vinifera wines obtained from family-run vineyards. Heavy metals contents detected were not of concern for any of the wines analyzed, however, copper accumulation in V. vinifera vineyard soils, and pollution deriving from other phytosanitary chemicals remain issues that in the case of Chambourcin vineyards could be solved at least in large part.

Perspectives of Wilson’s disease treatment

Objectives. Wilson’s disease (WD) is a genetic, neurodegenerative disorder caused by copper metabolism disturbances with subsequent pathological copper accumulation in organs and tissues (mainly liver and brain) with their secondary damage and clinical symptoms related to affected organs. The treatment of the disease is based on medications leading to negative body copper balance, i.e. (1) decreasing absorption of copper from the digestive tract (zinc salts); (2) increasing the copper excretion with urine (chelators: d-penicillamine, trientine, dimercaprol); and (3) liver transplant in specific clinical situations (acute liver failure, liver cirrhosis decompensation despite treatment). The article aims to review the available literature concerning the current research directions in WD treatment. Literature review. During the space of last years, intensive research into the new treatment of WD has started, including: (1) new pharmacological agents (modified thermostable trientine, trientine with delivery system to central nervous system, molybdenum salts, methanobactin, and others); (2) gene therapy; and (3) cells therapy (hepatocytes transplant). We conducted a targeted literature review of PubMed articles written in English, using the following search terms: “Wilson’s disease,” “treatment perspectives,” and “gene therapy.” Reviews, original articles, randomised controlled trials, meta-analyses, book chapters, and abstracts published up to April 2021 were included. Below, we present a narrative synthesis of the extracted data. Conclusions. Currently, chelators, medications decreasing absorption of copper from the digestive tract, and liver transplant are the treatment methods recommended by international societies as a WD treatment. Among the studies on new therapies for WD, the research with tetrathiomolybdate bis-choline is the most advanced and promising. Great hope can be associated with gene therapy.

474 Comparison Between Copper Sulfate and Dicopper Oxide on Body Weight and Copper Accumulation on Growing Pigs

There are several Cu sources in the market that have different effects on pigs. We hypothesized that supplementing therapeutic doses of Cu(I)oxide (Cu2O) in diets for growing pigs improves body weight (BW), bone mineralization, and reduces Cu accumulation in liver than supplementing pigs with Cu sulfate (CuSO4). Two-hundred growing pigs (initial BW: 11.5 ± 0.98 kg) were randomly allotted to 5 dietary treatments. Dietary treatments included the negative control (NC) diet without Cu supplementation, and 4 diets in which 125 or 250 mg/kg of Cu from CuSO4 or Cu2O were added to the NC diet. The experiment was divided into 4 phases. Pig weights were recorded on d 1 and at the end of each phase. Eight pigs per treatment were sacrificed last d of phases 1 and 4 to obtain samples of liver, spleen, and the right metacarpal. Pigs fed diets containing 250 mg/kg of Cu2O had greater (P &lt; 0.05) BW at the end of phases 1 and 2 than pigs fed the NC diet, and tended (P &lt; 0.10) to have greater BW at the end of phases 3 and 4 than pigs fed the other diets. Copper accumulation in liver and spleen increased with Cu dose, but at the end of phase 1, pigs fed 250 mg/kg CuSO4 had greater (P &lt; 0.05) Cu concentration in liver and spleen than pigs fed 250 mg/kg Cu2O. Pigs fed diets containing 250 mg/kg Cu2O had greater (P &lt; 0.05) quantities of bone ash and greater (P &lt; 0.05) concentrations of Ca, P, and Cu in bone ash than pigs fed the NC diets or diets containing CuSO4. Therefore, supplementing diets for growing pigs with therapeutic doses of Cu2O improves BW and bone mineralization with less Cu accumulation in liver compared with pigs fed diets containing CuSO4.

Ulva compressa from Copper-Polluted Sites Exhibits Intracellular Copper Accumulation, Increased Expression of Metallothioneins and Copper-Containing Nanoparticles in Chloroplasts

In order to analyze the mechanisms involved in copper accumulation in Ulva compressa, algae were collected at control sites of central and northern Chile, and at two copper-polluted sites of northern Chile. The level of intracellular copper, reduced glutathione (GSH), phytochelatins (PCs), PC2 and PC4, and transcripts encoding metallothioneins (MTs) of U. compressa, UcMT1, UcMT2 and UcMT3, were determined. Algae of control sites contained around 20 g of copper g−1 of dry tissue (DT) whereas algae of copper-polluted sites contained 260 and 272 g of copper g−1 of DT. Algae of control sites and copper-polluted sites did not show detectable amounts of GSH, the level of PC2 did not change among sites whereas PC4 was increased in one of the copper-polluted sites. The level of transcripts of UcMT1 and UcMT2 were increased in algae of copper-polluted sites, but the level of UcMT3 did not change. Algae of a control site and a copper-polluted site were visualized by transmission electron microscopy (TEM) and the existence of copper in electrodense particles was analyzed using energy dispersive x-ray spectroscopy (EDXS). Algae of copper-polluted sites showed electrodense nanoparticles containing copper in the chloroplasts, whereas algae of control sites did not. Algae of a control site, Cachagua, were cultivated without copper (control) and with 10 M copper for 5 days and they were analyzed by TEM-EDXS. Algae cultivated with copper showed copper-containing nanoparticles in the chloroplast whereas control algae did not. Thus, U. compressa from copper-polluted sites exhibits intracellular copper accumulation, an increase in the level of PC4 and expression of UcMTs, and the accumulation of copper-containing particles in chloroplasts.

Diagnosis of Wilson Disease and Its Phenotypes by Using Artificial Intelligence

WD is caused by ATP7B variants disrupting copper efflux resulting in excessive copper accumulation mainly in liver and brain. The diagnosis of WD is challenged by its variable clinical course, onset, morbidity, and ATP7B variant type. Currently it is diagnosed by a combination of clinical symptoms/signs, aberrant copper metabolism parameters (e.g., low ceruloplasmin serum levels and high urinary and hepatic copper concentrations), and genetic evidence of ATP7B mutations when available. As early diagnosis and treatment are key to favorable outcomes, it is critical to identify subjects before the onset of overtly detrimental clinical manifestations. To this end, we sought to improve WD diagnosis using artificial neural network algorithms (part of artificial intelligence) by integrating available clinical and molecular parameters. Surprisingly, WD diagnosis was based on plasma levels of glutamate, asparagine, taurine, and Fischer’s ratio. As these amino acids are linked to the urea–Krebs’ cycles, our study not only underscores the central role of hepatic mitochondria in WD pathology but also that most WD patients have underlying hepatic dysfunction. Our study provides novel evidence that artificial intelligence utilized for integrated analysis for WD may result in earlier diagnosis and mechanistically relevant treatments for patients with WD.