Copper (Cu) induced changes of lipid metabolism through oxidative stress-mediated autophagy and Nrf2/PPARγ pathways

Toxicity study of mineral medicine haematitum

ETHNOPHARMACOLOGICAL RELEVANCE

Haematitum, a time-honored mineral-based Chinese medicine, has been used medicinally in China for over 2000 years. It is now included in the Chinese Pharmacopoeia and used clinically for treating digestive and respiratory diseases. The Chinese Materia Medica records that it is toxic and should not be taken for a long period, but there are few research reports on the toxicity of Haematitum and its potential toxicity mechanisms.

AIM OF THE STUDY

This study aimed to evaluate the toxicity of Haematitum and calcined Haematitum, including organ toxicity, neurotoxicity, and reproductive toxicity. Further, it is also necessary to explore the mechanism of Haematitum toxicity and to provide a reference for the safe clinical use of the drug.

MATERIALS AND METHODS

The samples of Haematitum and calcined Haematitum decoctions were prepared. KM mice were treated with samples by gavage for 10 days, and lung damage and apoptosis were assessed by HE staining and TUNEL staining of lung tissues respectively. Metabolomics analysis was performed by HPLC-MS. Metallomics analysis was performed by ICP-MS. In addition, C. elegans was used as a model for 48 h exposure to examine the neurotoxicity and reproductive toxicity-related indices of Haematitum, including locomotor behaviors, growth and development, reproductive behaviors, AChE activities, sensory behaviors, apoptosis, and ROS levels.

RESULTS

The use of large doses of Haematitum decoction caused lung damage in mice. Neither calcined Haematitum decoction nor Haematitum decoction at clinically used doses showed organ damage. Metabolomics results showed that disorders in lipid metabolic pathways such as sphingolipid metabolism and glycerophospholipid metabolism may be important factors in Haematitum-induced pulmonary toxicity. High doses of Haematitum decoction caused neurological damage to C. elegans, while low doses of Haematitum decoction and calcined Haematitum decoction showed no significant neurotoxicity. Decoction of Haematitum and calcined Haematitum did not show reproductive toxicity to C. elegans. Toxicity was also not observed in the control group of iron (Ⅱ) and iron (Ⅲ) ions in equal amounts with high doses of Haematitum.

CONCLUSIONS

Haematitum is relatively safe for routine doses and short-term use. Calcination can significantly reduce Haematitum toxicity, and this study provides a reference for safe clinical use.

The Correlation Between Serum Copper and Non-alcoholic Fatty Liver Disease in American Adults: an Analysis Based on NHANES 2011 to 2016

Copper functions as an essential micronutrient influencing diverse metabolic processes in mammals, encompassing oxidative stress responses, lipid metabolism, and participation in enzymatic reactions. However, the impact of serum copper on non-alcoholic fatty liver disease (NAFLD) remains controversial. Our aim was to explore the precise correlation between serum copper and NAFLD in a large-scale population-based study. A total of 1377 participants from the National Health and Nutrition Examination Survey (NHANES) 2011-2016 were included in our study. The diagnosis of NAFLD and its progress to advanced liver fibrosis were based on serological indexes. One-way ANOVA, Kruskal-Wallis H test, and Chi-square test were used to access variations between quartiles groups of serum copper. We conducted multivariate-adjusted logistic regression models and subgroup analyses to investigate the association between serum copper and NAFLD, along with several metabolic diseases. Among the 1377 participants, 661 were diagnosed with NAFLD, and 141 of whom were classified into advanced liver fibrosis. Higher serum copper levels (≥ 21.00 μmol/L) were associated with an increased incidence of NAFLD (odds ratio (OR) = 2.07 (1.38-3.10), p < 0.001), as well as advanced liver fibrosis (OR = 2.40 (1.17-5.19), p = 0.025). Moreover, serum copper exhibited a positive correlation with hypertension, overweight, and abdominal obesity, all of which have been identified as risk factors of NAFLD. Additionally, female participants, under the age of 60, and with a higher body mass index (BMI) (> 24.9 kg/m2) emerged as the most vulnerable subgroup concerning the relationship between serum copper and NAFLD. In the U.S. population, a notable association has been identified, linking elevated serum copper to an increased susceptibility for both the onset and progression of NAFLD, along with several metabolic disorders associated with NAFLD. The adverse effects of excess copper warrant attention in the context of public health considerations.

Copper homeostasis and cuproptosis in health and disease

Copper is a vital trace element in human physiology, essential for the synthesis of numerous crucial metabolic enzymes and facilitation of various biological processes. Regulation of copper levels within a narrow range is imperative for maintaining metabolic homeostasis. Numerous studies have demonstrated the significant roles of copper homeostasis and cuproptosis in health and disease pathogenesis. However, a comprehensive and up-to-date systematic review in this domain remains absent. This review aims to consolidate recent advancements in understanding the roles of cuproptosis and copper homeostasis in health and disease, focusing on the underlying mechanisms and potential therapeutic interventions. Dysregulation of copper homeostasis, manifesting as either copper excess or deficiency, is implicated in the etiology of various diseases. Cuproptosis, a recently identified form of cell death, is characterized by intracellular copper overload. This phenomenon mediates a diverse array of evolutionary processes in organisms, spanning from health to disease, and is implicated in genetic disorders, liver diseases, neurodegenerative disorders, and various cancers. This review provides a comprehensive summary of the pathogenic mechanisms underlying cuproptosis and copper homeostasis, along with associated targeted therapeutic agents. Furthermore, it explores future research directions with the potential to yield significant advancements in disease treatment, health management, and disease prevention.

Alleviation of Copper-Induced Hepatotoxicity by Bergenin: Diminution of Oxidative Stress, Inflammation, and Apoptosis via Targeting SIRT1/FOXO3a/NF-κB Axes and p38 MAPK Signaling

Despite its biological importance, excess copper induces organ damage, especially to the liver. Disruption of critical signaling cascades that control redox status, inflammatory responses, and cellular apoptosis significantly contributes to the copper-induced hepatotoxicity. The present work explored the hepatoprotective ability of bergenin against the copper-induced hepatotoxicity using male Wistar rats as a mammalian model. The results revealed that bergenin suppressed the copper-evoked histopathological changes and hepatocellular necrosis as indicated by decreased activity of the liver enzymes ALT and AST in the sera of the copper-intoxicated rats. It decreased hepatic copper content and the copper-induced oxidative stress as revealed by reduced lipid peroxidation and improved activity of the antioxidant enzymes thioredoxin reductase, glutathione peroxidase, catalase, and superoxide dismutase. Bergenin downregulated the inflammatory cytokines TNF-α and IL-6, and the inflammatory cell infiltration to the liver tissues. Additionally, it inhibited the copper-induced apoptosis as indicated by significant reduction in caspase-3 activity. At the molecular level, bergenin activated the antioxidant transcription factor FOXO3a, inhibited the nuclear translocation of the inflammatory transcription factor NF-κB, and suppressed the inflammatory signaling molecules p38 MAPK and c-Fos. Interestingly, bergenin improved the expression of the anti-apoptotic protein Bcl2 and reduced the pro-apoptotic protein BAX. Bergenin markedly enhanced the expression of the histone deacetylase protein SIRT1 that regulates activity of NF-κB and FOXO3a. Collectively, these findings highlight the alleviating activity of bergenin against the copper-induced hepatotoxicity via controlling oxidative stress, inflammation, and apoptosis potentially through upregulation of SIRT1, activation of FOXO3a along with suppression of NF-κB and p38 MAPK signaling.

Cuproptosis in microsatellite stable colon cancer cells affects the cytotoxicity of CD8+T through the WNT signaling pathway

The microsatellite stable (MSS) colon cancer (CC) has long been considered resistant to immunotherapy. Cuproptosis, as a novel form of cell death, may interact with tumor immunity. This project focused on the impact of cuproptosis on the cytotoxicity of CD8+T in MSS CC, aiming to provide effective clues for improving the treatment strategy of MSS CC. The study developed an MSS CC cuproptosis model using 50 nM elesclomol and 1 μM CuCl2. Cuproptotic SW480 cells were directly co-cultured with CD8+ T cells. Cuproptosis levels were assessed via intracellular copper ion detection, Western blot, and confocal laser scanning microscopy. CCK-8, Hochest/PI staining, CFSE cell proliferation assay, LDH cytotoxicity detection, and ELISA were used to evaluate CD8+ T cell immune activity and cytotoxicity. Transcriptome sequencing and bioinformatics analysis identified regulated signals in cuproptotic SW480 cells. A rescue experiment utilized a WNT pathway activator (BML-284). PD-L1 expression in cells/membranes was analyzed using qRT-PCR, Western blot, and flow cytometry. NSG mice were immunoreconstituted, and the effects of cuproptosis on immune infiltration and cancer progression in MSS CC mice were assessed using ELISA and immunohistochemistry (IHC). Treatment with 50 nM elesclomol and 1 μM CuCl2 significantly increased cuproptosis in SW480 cells. Co-culture with CD8+ T cells enhanced their cytotoxicity. Sequencing revealed cuproptosis-mediated modulation of immune and inflammatory pathways, including WNT signaling. Rescue experiments showed downregulation of WNT signaling in cuproptotic SW480 cells. Indirectly, CD8+ T cell immune function was enhanced by reducing PD-L1 expression. In mice, cuproptosis resulted in increased infiltration of CD8+ T cells in tumor tissue, leading to delayed cancer progression compared to the control group. Cuproptosis in MSS CC cells enhances the cytotoxicity of CD8+ T cells, which may be achieved through downregulation of the WNT signaling pathway and decreased expression of PD-L1. In the future, drugs that can induce cuproptosis may be a promising approach to improve MSS CC immunotherapy.

Astaxanthin Alleviates Hepatic Lipid Metabolic Dysregulation Induced by Microcystin-LR

Microcystin-LR (MC-LR), frequently generated by cyanobacteria, has been demonstrated to raise the likelihood of liver disease. Few previous studies have explored the potential antagonist against MC-LR. Astaxanthin (ASX) has been shown to possess various beneficial effects in regulating lipid metabolism in the liver. However, whether ASX could alleviate MC-LR-induced hepatic lipid metabolic dysregulation is as yet unclear. In this work, the important roles and mechanisms of ASX in countering MC-LR-induced liver damage and lipid metabolic dysregulation were explored for the first time. The findings revealed that ASX not only prevented weight loss but also enhanced liver health after MC-LR exposure. Moreover, ASX effectively decreased triglyceride, total cholesterol, aspartate transaminase, and alanine aminotransferase contents in mice that were elevated by MC-LR. Histological observation showed that ASX significantly alleviated lipid accumulation and inflammation induced by MC-LR. Mechanically, ASX could significantly diminish the expression of genes responsible for lipid generation (Srebp-1c, Fasn, Cd36, Scd1, Dgat1, and Pparg), which probably reduced lipid accumulation induced by MC-LR. Analogously, MC-LR increased intracellular lipid deposition in THLE-3 cells, while ASX decreased these symptoms by down-regulating the expression of key genes in the lipid synthesis pathway. Our results implied that ASX played a crucial part in lipid synthesis and effectively alleviated MC-LR-induced lipid metabolism dysregulation. ASX might be developed as a novel protectant against hepatic impairment and lipid metabolic dysregulation associated with MC-LR. This study offers new insights for further management of MC-LR-related metabolic diseases.

Mitochondria UPR stimulation by pelargonidin-3-glucoside contributes to ameliorating lipid accumulation under copper exposure

Intensification of copper pollution in the environment has led to its excessive accumulation in humans, causing oxidative stress and lipid metabolism disorders. It is necessary to look for effective targets and safe methods to alleviate copper toxicity. Pelargonidin-3-glucoside (Pg3G) is a natural anthocyanin with metal ion chelating ability and multiple physiological activities. In this study, lipid accumulation was investigated under copper exposure in Caenorhabditis elegans which can be improved by Pg3G. Transcriptome analysis revealed that differentially expressed genes are enriched in lipid metabolism and protein folding/degradation. Pg3G activated mitochondrial unfold protein response (UPRmt) to mitigate mitochondrial damage caused by copper and regulated the expression of genes involved in lipid absorption, transport, and synthesis, thereby reducing lipid levels in C. elegans. This improvement disappeared in the ubl-5 knockout strain, indicating that ubl-5 is one target of Pg3G. Meanwhile, in HepG2 cells, Pg3G enhanced the cellular antioxidant capacity by activating UPRmt for maintaining mitochondrial homeostasis, followed by inhibition of excessive lipid accumulation. Overall, these results suggested that UPRmt activation can be a strategy for mitigating lipid disorders induced by copper and Pg3G with excellent ability to resist oxidative stress specially targeted for ubl-5 has a promising application in controlling copper contamination.

Copper homeostasis and cuproptosis-related genes: Therapeutic perspectives in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD), a metabolic-associated fatty liver disease, has become the most common chronic liver disease worldwide. Recently, the discovery of cuproptosis, a newly identified mode of cell death, further highlighted the importance of copper in maintaining metabolic homeostasis. An increasing number of studies have confirmed that liver copper metabolism is closely related to the pathogenesis of NAFLD. However, the relationship between NAFLD and copper metabolism, especially cuproptosis, remains unclear. In this review, we aim to summarize the current understanding of copper metabolism and its dysregulation, particularly the role of copper metabolism dysregulation in the pathogenesis of NAFLD. More importantly, this review emphasizes potential gene-targeted therapeutic strategies, challenges and the future of cuproptosis-related genes in the treatment of NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.

Copper-loaded Milk-Protein Derived Microgel Preserves Cardiac Metabolic Homeostasis After Myocardial Infarction

Myocardial Infarction (MI) is a leading cause of death worldwide. Metabolic modulation is a promising therapeutic approach to prevent adverse remodeling after MI. However, whether material-derived cues can treat MI through metabolic regulation is mainly unexplored. Herein, a Cu2+ loaded casein microgel (CuCMG) aiming to rescue the pathological intramyocardial metabolism for MI amelioration is developed. Cu2+ is an important ion factor involved in metabolic pathways, and intracardiac copper drain is observed after MI. It is thus speculated that intramyocardial supplementation of Cu2+ can rescue myocardial metabolism. Casein, a milk-derived protein, is screened out as Cu2+ carrier through molecular-docking based on Cu2+ loading capacity and accessibility. CuCMGs notably attenuate MI-induced cardiac dysfunction and maladaptive remodeling, accompanied by increased angiogenesis. The results from unbiased transcriptome profiling and oxidative phosphorylation analyses support the hypothesis that CuCMG prominently rescued the metabolic homeostasis of myocardium after MI. These findings enhance the understanding of the design and application of metabolic-modulating biomaterials for ischemic cardiomyopathy therapy.

Haloacetamides disinfection by-products, a potential risk factor for nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder characterized by abnormal lipid deposition, with oxidative stress being a risk factor in its onset and progression. Haloacetamides (HAcAms), as unregulated disinfection by-products in drinking water, may alter the incidence and severity of NAFLD through the production of oxidative stress. We explored whether HAcAms at 1, 10, and 100-fold concentrations in Shanghai drinking water perturbed lipid metabolism in normal human liver LO-2 cells. CRISPR/Cas9 was used to construct a LO-2 line with stable NRF2 knock-down (NRF2-KD) to investigate the mechanism underlying abnormal lipid accumulation and hepatocyte damage caused by mixed exposure to HAcAms. At 100-fold real-world concentration, HAcAms caused lipid deposition and increased triglyceride accumulation in LO-2 cells, consistent with altered de novo lipogenesis. Differences in responses to HAcAms in normal and NRF2-KD LO-2 cells indicated that HAcAms caused hepatocyte lipid deposition and triglyceride accumulation by activation of the NRF2/PPARγ pathway and aggravated liver cell toxicity by inducing ferroptosis. These results indicate that HAcAms are important risk factors for NAFLD. Further observations and verifications of the effect of HAcAms on NAFLD in the population are warranted in the future.

Focus on cuproptosis: Exploring new mechanisms and therapeutic application prospects of cuproptosis regulation

Cuproptosis is a novel form of regulated cell death, which plays an important role in the physiological and pathological processes of the human body. Despite the increasing research on cuproptosis-related genes (CRGs) and their correlation with diseases, the pathogenesis of cuproptosis-related diseases remains unclear. Furthermore, there is a lack of reviews on the emerging technologies for regulating cuproptosis in disease treatment. This study delves into the copper-induced cell death mechanism, distinguishing cuproptosis from mechanisms like oxidative stress, glutathione synthesis inhibition, and ubiquitin-proteasome system inhibition. Several long-standing mysteries of diseases such as Wilson's disease and Menkes disease may be attributed to the occurrence of cuproptosis. In addition, we also review the detection indicators related to cuproptosis, providing targets for the diagnosis of cuproptosis-related diseases, and summarize the application value of cuproptosis in tumor therapy to better elucidate the impact of copper in cell death and diseases, and thus to promote the application prospects and possible strategies of cuproptosis-related substances, such as copper ion chelators, copper ion carriers, and copper nanomaterials, in disease therapy.

Copper homeostasis and cuproptosis in radiation-induced injury

Radiation therapy for cancer treatment brings about a series of radiation injuries to normal tissues. In recent years, the discovery of copper-regulated cell death, cuproptosis, a novel form of programmed cell death, has attracted widespread attention and exploration in various biological functions and pathological mechanisms of copper metabolism and cuproptosis. Understanding its role in the process of radiation injury may open up new avenues and directions for exploration in radiation biology and radiation oncology, thereby improving tumor response and mitigating adverse reactions to radiotherapy. This review provides an overview of copper metabolism, the characteristics of cuproptosis, and their potential regulatory mechanisms in radiation injury.

Association of plasma metals with resting-state functional connectivity in ischemic stroke

BACKGROUND

Metal exposure has long been considered a significant risk factor for ischemic stroke. However, existing data on the effects of metal exposure on brain function in ischemic stroke are limited. Therefore, this study aimed to explore the correlation between exposure to various metals and changes in resting-state functional connectivity (rs-FC) in ischemic stroke patients.

METHODS

This study included 28 acute ischemic stroke patients with hemiplegia and 28 matched healthy controls (HCs). All participants underwent T1-weighted MRI and 3.0 T resting-state functional magnetic resonance imaging (fMRI). After MRI acquisition, the rs-FC between 137 cortical and subcortical regions was extracted and preprocessed. Plasma levels of 19 metals were measured using inductively coupled plasma mass spectrometry (ICP-MS). The Bayesian kernel machine regression (BKMR) model and the weighted quantile sum regression (WQS) model were used to assess the overall effect of metal mixture exposure. The severity of neurological deficits in each acute ischemic stroke patient was evaluated using the National Institutes of Health Stroke Scale (NIHSS). Additionally, the associations between exposure to various metals and modifications in brain functional connectivity were determined using Pearson or Spearman correlation analysis.

RESULTS

Bilateral brain connectivity was significantly decreased compared to controls and was associated with neurological impairment in ischemic stroke. In patients with ischemic stroke, the plasma concentrations of Cr (p < 0.001), Cu (p = 0.004), As (p = 0.010), Cs (p = 0.046), Rb (p = 0.041), and Sb (p = 0.001) were significantly higher than those in the HCs, whereas the plasma Tl concentrations (p = 0.022) were significantly lower. The results of the BKMR and WQS models showed that combined exposure to metal mixtures was linked to a higher risk of ischemic stroke. Cr was positively correlated with the rs-FC between the left Rolandic_Oper and the left Supp_Motor_Area (r = 0.414, p = 0.029), while negatively correlated with the rs-FC between the right Parietal_Inf and the left supramarginal (r = -0.398, p = 0.037). Cu was negatively correlated with the rs-FC between the left paracentral lobule and the left thalamus (r = -0.409, p = 0.031). Tl was positively correlated with the rs-FC between the right Parietal_Inf and the left supramarginal cortex (r = 0.590, p = 0.001). A negative correlation was observed between Cs and rs-FC between the right Cingulate_Mid and left Occipital_Sup (r = -0.429, p = 0.024). Sb was negatively correlated with the rs-FC between the left Parietal_Inf and the right SupraMarginal (r = -0.384, p = 0.044), the right Parietal_Inf and the left SupraMarginal (r = -0.583, p = 0.001), and the left SupraMarginal and the right SupraMarginal (r = -0.377, p = 0.048).

CONCLUSION

Plasma levels of Cr, Cu, Tl, Cs, and Sb were associated with altered rs-FC in brain regions related to motor control, sensory integration, executive function, language processing, and emotional regulation in ischemic stroke patients with basal ganglia infarction.

Copper induces cytotoxicity in freshwater bivalve Anodonta woodiana hemocytes

Hemocytes of freshwater bivalves are an important target model for evaluating copper (Cu) toxicity in vitro, with excess Cu causing adverse responses in these organisms. Despite this, the mechanisms underlying cytotoxicity remain poorly understood. The freshwater bivalve Anodonta woodiana, employed as a model organism in freshwater environments, was utilized in this study. Hemocytes of A. woodiana were exposed to various aqueous Cu treatments (0.001, 0.01, 0.1, 1, and 10 mg/L), and a control group (no Cu added) for 3 h to investigate the cytotoxic mechanisms of Cu. The results showed a significant increase in the production of reactive oxygen species in hemocytes of all Cu exposed groups compared to the control (p < 0.05). Remarkably, Cu treatments disrupted the cellular membrane (p < 0.05) but did not induce significant changes in the stability of the lysosomal membrane. Cu targeted the mitochondria, leading to a reduction in mitochondrial membrane potential. Additionally, all Cu treatments significantly increased the degree of DNA damage (p < 0.05). Cellular damage and a significant decline in cell viability were observed when the Cu exposure concentration reached 0.1, 1, and 10 mg/L (p < 0.05). Our study provides new insights into the cytotoxicity mechanisms triggered by Cu in hemocytes of the freshwater bivalve A. woodiana, even under environmentally relevant conditions of 0.01 mg/L exposure.

Cuproptosis and copper deficiency in ischemic vascular injury and repair

Ischemic vascular diseases are on the rise globally, including ischemic heart diseases, ischemic cerebrovascular diseases, and ischemic peripheral arterial diseases, posing a significant threat to life. Copper is an essential element in various biological processes, copper deficiency can reduce blood vessel elasticity and increase platelet aggregation, thereby increasing the risk of ischemic vascular disease; however, excess copper ions can lead to cytotoxicity, trigger cell death, and ultimately result in vascular injury through several signaling pathways. Herein, we review the role of cuproptosis and copper deficiency implicated in ischemic injury and repair including myocardial, cerebral, and limb ischemia. We conclude with a perspective on the therapeutic opportunities and future challenges of copper biology in understanding the pathogenesis of ischemic vascular disease states.

Disulfiram downregulates ferredoxin 1 to maintain copper homeostasis and inhibit inflammation in cerebral ischemia/reperfusion injury

In the current study, we aimed to investigate whether disulfiram (DSF) exerts a neuroprotective role in cerebral ischemiareperfusion (CI-RI) injury by modulating ferredoxin 1 (FDX1) to regulate copper ion (Cu) levels and inhibiting inflammatory responses. To simulate CI-RI, a transient middle cerebral artery occlusion (tMCAO) model in C57/BL6 mice was employed. Mice were administered with or without DSF before and after tMCAO. Changes in infarct volume after tMCAO were observed using TTC staining. Nissl staining and hematoxylin-eosin (he) staining were used to observe the morphological changes of nerve cells at the microscopic level. The inhibitory effect of DSF on initial inflammation was verified by TUNEL assay, apoptosis-related protein detection and iron concentration detection. FDX1 is the main regulatory protein of copper death, and the occurrence of copper death will lead to the increase of HSP70 stress and inflammatory response. Cuproptosis-related proteins and downstream inflammatory factors were detected by western blotting, immunofluorescence staining, and immunohistochemistry. The content of copper ions was detected using a specific kit, while electron microscopy was employed to examine mitochondrial changes. We found that DSF reduced the cerebral infarction volume, regulated the expression of cuproptosis-related proteins, and modulated copper content through down regulation of FDX1 expression. Moreover, DSF inhibited the HSP70/TLR-4/NLRP3 signaling pathway. Collectively, DSF could regulate Cu homeostasis by inhibiting FDX1, acting on the HSP70/TLR4/NLRP3 pathway to alleviate CI/RI. Accordingly, DSF could mitigate inflammatory responses and safeguard mitochondrial integrity, yielding novel therapeutic targets and mechanisms for the clinical management of ischemia-reperfusion injury.

Regulation of metabolic microenvironment with a nanocomposite hydrogel for improved bone fracture healing

Bone nonunion poses an urgent clinical challenge that needs to be addressed. Recent studies have revealed that the metabolic microenvironment plays a vital role in fracture healing. Macrophages and bone marrow-derived mesenchymal stromal cells (BMSCs) are important targets for therapeutic interventions in bone fractures. Itaconate is a TCA cycle metabolite that has emerged as a potent macrophage immunomodulator that limits the inflammatory response. During osteogenic differentiation, BMSCs tend to undergo aerobic glycolysis and metabolize glucose to lactate. Copper ion (Cu2+) is an essential trace element that participates in glucose metabolism and may stimulate glycolysis in BMSCs and promote osteogenesis. In this study, we develop a 4-octyl itaconate (4-OI)@Cu@Gel nanocomposite hydrogel that can effectively deliver and release 4-OI and Cu2+ to modulate the metabolic microenvironment and improve the functions of cells involved in the fracture healing process. The findings reveal that burst release of 4-OI reduces the inflammatory response, promotes M2 macrophage polarization, and alleviates oxidative stress, while sustained release of Cu2+ stimulates BMSC glycolysis and osteogenic differentiation and enhances endothelial cell angiogenesis. Consequently, the 4-OI@Cu@Gel system achieves rapid fracture healing in mice. Thus, this study proposes a promising regenerative strategy to expedite bone fracture healing through metabolic reprogramming of macrophages and BMSCs.

A narrative review on the mechanism of natural flavonoids in improving glucolipid metabolism disorders

Glucolipid metabolism disorder (GLMD) is a complex chronic disease characterized by glucose and lipid metabolism disorders with a complex and diverse etiology and rapidly increasing incidence. Many studies have identified the role of flavonoids in ameliorating GLMD, with mechanisms related to peroxisome proliferator-activated receptors, nuclear factor kappa-B, AMP-activated protein kinase, nuclear factor (erythroid-derived 2)-like 2, glucose transporter type 4, and phosphatidylinositol-3-kinase/protein kinase B pathway. However, a comprehensive summary of the flavonoid effects on GLMD is lacking. This study reviewed the roles and mechanisms of natural flavonoids with different structures in the treatment of GLMD reported globally in the past 5 years and provides a reference for developing flavonoids as drugs for treating GLMD.

NRF2-mediated regulation of lipid pathways in viral infection

The first line of defense against viral infection of the host cell is the cellular lipid membrane, which is also a crucial first site of contact for viruses. Lipids may sometimes be used as viral receptors by viruses. For effective infection, viruses significantly depend on lipid rafts during the majority of the viral life cycle. It has been discovered that different viruses employ different lipid raft modification methods for attachment, internalization, membrane fusion, genome replication, assembly, and release. To preserve cellular homeostasis, cells have potent antioxidant, detoxifying, and cytoprotective capabilities. Nuclear factor erythroid 2-related factor 2 (NRF2), widely expressed in many tissues and cell types, is one crucial component controlling electrophilic and oxidative stress (OS). NRF2 has recently been given novel tasks, including controlling inflammation and antiviral interferon (IFN) responses. The activation of NRF2 has two effects: it may both promote and prevent the development of viral diseases. NRF2 may also alter the host's metabolism and innate immunity during viral infection. However, its primary function in viral infections is to regulate reactive oxygen species (ROS). In several research, the impact of NRF2 on lipid metabolism has been examined. NRF2 is also involved in the control of lipids during viral infection. We evaluated NRF2's function in controlling viral and lipid infections in this research. We also looked at how lipids function in viral infections. Finally, we investigated the role of NRF2 in lipid modulation during viral infections.

Copper homeostasis dysregulation in respiratory diseases: a review of current knowledge

Cu is an essential micronutrient for various physiological processes in almost all human cell types. Given the critical role of Cu in a wide range of cellular processes, the local concentrations of Cu and the cellular distribution of Cu transporter proteins in the lung are essential for maintaining a steady-state internal environment. Dysfunctional Cu metabolism or regulatory pathways can lead to an imbalance in Cu homeostasis in the lungs, affecting both acute and chronic pathological processes. Recent studies have identified a new form of Cu-dependent cell death called cuproptosis, which has generated renewed interest in the role of Cu homeostasis in diseases. Cuproptosis differs from other known cell death pathways. This occurs through the direct binding of Cu ions to lipoylated components of the tricarboxylic acid cycle during mitochondrial respiration, leading to the aggregation of lipoylated proteins and the subsequent downregulation of Fe-S cluster proteins, which causes toxic stress to the proteins and ultimately leads to cell death. Here, we discuss the impact of dysregulated Cu homeostasis on the pathogenesis of various respiratory diseases, including asthma, chronic obstructive pulmonary disease, idiopathic interstitial fibrosis, and lung cancer. We also discuss the therapeutic potential of targeting Cu. This study highlights the intricate interplay between copper, cellular processes, and respiratory health. Copper, while essential, must be carefully regulated to maintain the delicate balance between necessity and toxicity in living organisms. This review highlights the need to further investigate the precise mechanisms of copper interactions with infections and immune inflammation in the context of respiratory diseases and explore the potential of therapeutic strategies for copper, cuproptosis, and other related effects.

The Protection of EGCG Against 6-OHDA-Induced Oxidative Damage by Regulating PPARγ and Nrf2/HO-1 Signaling

6-Hydroxydopamine (6-OHDA) is a classic neurotoxin that has been widely used in Parkinson's disease research. 6-OHDA can increase intracellular reactive oxygen species (ROS) and can cause cell damage, which can be attenuated with (-)-Epigallocatechin-3-gallate (EGCG) treatment. However, the mechanism by which EGCG alters the 6-OHDA toxicity remains unclear; In this study, we found 6-OHDA (25 μM) alone increased intracellular ROS concentration in N27 cells, which was attenuated by pretreating with EGCG (100 μM). We evaluated the intracellular oxidative damage by determining the level of thiobarbituric acid reactive substances (TBARS) and protein carbonyl content. 6-OHDA significantly increased TBARS by 82.7% (P < .05) and protein carbonyl content by 47.8 (P < .05), compared to the control. Pretreatment of EGCG decreased TBARS and protein carbonyls by 36.4% (P < .001) and 27.7% (P < .05), respectively, compared to 6-OHDA alone treatment. Antioxidant effect was tested with E2-related factor 2 (Nrf2), heme oxygenase-1(HO-1) and peroxisome-proliferator activator receptor γ (PPARγ) expression. 6-OHDA increased Nrf2 expression by 69.6% (P < .001), HO-1 by 173.3% (P < .001), and PPARγ by 122.7% (P < .001), compared with untreatment. EGCG pretreatment stabilized these alterations induced by 6-OHDA. Our results suggested that the neurotoxicity of 6-OHDA in N27 cells was associated with ROS pathway, whereas pretreatment of EGCG suppressed the ROS generation and deactivated the Nrf2/HO-1 and PPARγ expression.

Elucidating cuproptosis in metabolic dysfunction-associated steatotic liver disease

Emerging research into metabolic dysfunction-associated steatotic liver disease (MASLD) up until January 2024 has highlighted the critical role of cuproptosis, a unique cell death mechanism triggered by copper overload, in the disease's development. This connection offers new insights into MASLD's complex pathogenesis, pointing to copper accumulation as a key factor that disrupts lipid metabolism and insulin sensitivity. The identification of cuproptosis as a significant contributor to MASLD underscores the potential for targeting copper-mediated pathways for novel therapeutic approaches. This promising avenue suggests that managing copper levels could mitigate MASLD progression, offering a fresh perspective on treatment strategies. Further investigations into how cuproptosis influences MASLD are essential for unraveling the detailed mechanisms at play and for identifying effective interventions. The focus on copper's role in liver health opens up the possibility of developing targeted therapies that address the underlying causes of MASLD, moving beyond symptomatic treatment to tackle the root of the problem. The exploration of cuproptosis in the context of MASLD exemplifies the importance of understanding metal homeostasis in metabolic diseases and represents a significant step forward in the quest for more effective treatments. This research direction lights path for innovative MASLD management and reversal.

Supplementation of Micro- and Macronutrients-A Role of Nutritional Status in Non-Alcoholic Fatty Liver Disease

Non-alcoholic fatty liver disease (NAFLD) is a condition in which the pathological cumulation of fat with coexisting inflammation and damage of hepatic cells leads to progressive dysfunctions of the liver. Except for the commonly well-known major causes of NAFLD such as obesity, dyslipidemia, insulin resistance, or diabetes, an unbalanced diet and imbalanced nutritional status should also be taken into consideration. In this narrative review, we summarized the current knowledge regarding the micro- and macronutrient status of patients suffering from NAFLD considering various diets and supplementation of chosen supplements. We aimed to summarize the knowledge indicating which nutritional impairments may be associated with the onset and progression of NAFLD at the same time evaluating the potential therapy targets that could facilitate the healing process. Except for the above-mentioned objectives, one of the most important aspects of this review was to highlight the possible strategies for taking care of NAFLD patients taking into account the challenges and opportunities associated with the micronutrient status of the patients. The current research indicates that a supplementation of chosen vitamins (e.g., vitamin A, B complex, C, or D) as well as chosen elements such as zinc may alleviate the symptoms of NAFLD. However, there is still a lack of sufficient data regarding healthy ranges of dosages; thus, further research is of high importance in this matter.

Oxidative stress, inflammation, and steatosis elucidate the complex dynamics of HgCl2 induced liver damage in Channa punctata

Water bodies are highly pollution-prone areas in which mercury (Hg) is considered as a major menace to aquatic organisms. However, the information about the toxicity of mercuric chloride (HgCl2) in a vital organ such as the liver of fish is still inadequate. This study aimed to assess the impact of mercuric chloride (HgCl2) exposure on the liver of Channa punctata fish over 15, 30, and 45 days, at two different concentrations (0.039 mg/L and 0.078 mg/L). Mercury is known to be a significant threat to aquatic life, and yet, information regarding its effects on fish liver remains limited. The results of this study demonstrate that exposure to HgCl2 significantly increases oxidative stress markers, such as lipid peroxidation (LPO) and protein carbonyls (PC), as well as the levels of serum glutamic-oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) in the fish. Additionally, the transcriptional and protein analysis of specific genes and molecules associated with necroptosis and inflammation, such as ABCG2, TNF α, Caspase 3, RIPK 3, IL-1β, Caspase-1, IL-18, and RIPK1, confirm the occurrence of necroptosis and inflammation in the liver. Histopathological and ultrastructural examinations of the liver tissue further reveal a significant presence of liver steatosis. Interestingly, the upregulation of PPARα suggests that the fish's body is actively responding to counteract the effects of liver steatosis. This study provides a comprehensive analysis of oxidative stress, biochemical changes, gene expression, protein profiles, and histological findings in the liver tissue of fish exposed to mercury pollution in freshwater environments.

Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.

Copper homeostasis in chronic kidney disease and its crosstalk with ferroptosis

Chronic kidney disease (CKD) has become a global public health problem with high morbidity and mortality. Renal fibrosis can lead to end-stage renal disease (ESRD). However, there is still no effective treatment to prevent or delay the progression of CKD into ESRD. Therefore, exploring the pathogenesis of CKD is essential for preventing and treating CKD. There are a variety of trace elements in the human body that interact with each other within a complex regulatory network. Iron and copper are both vital trace elements in the body. They are critical for maintaining bodily functions, and the dysregulation of their metabolism can cause many diseases, including kidney disease. Ferroptosis is a new form of cell death characterized by iron accumulation and lipid peroxidation. Studies have shown that ferroptosis is closely related to kidney disease. However, the role of abnormal copper metabolism in kidney disease and its relationship with ferroptosis remains unclear. Here, our current knowledge regarding copper metabolism, its regulatory mechanism, and the role of abnormal copper metabolism in kidney diseases is summarized. In addition, we discuss the relationship between abnormal copper metabolism and ferroptosis to explore the possible pathogenesis and provide a potential therapeutic target for CKD.

Targeting Nrf2 to treat thyroid cancer

Oxidative stress (OS) is recognized as a contributing factor in the development and progression of thyroid cancer. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a pivotal transcription factor involved in against OS generated by excessive reactive oxygen species (ROS). It governs the expression of a wide array of genes implicated in detoxification and antioxidant pathways. However, studies have demonstrated that the sustained activation of Nrf2 can contribute to tumor progression and drug resistance in cancers. The expression of Nrf2 was notably elevated in papillary thyroid cancer tissues compared to normal tissues, indicating that Nrf2 may play an oncogenic role in the development of papillary thyroid cancer. Nrf2 and its downstream targets are involved in the progression of thyroid cancer by impacting the prognosis and ferroptosis. Furthermore, the inhibition of Nrf2 can increase the sensitivity of target therapy in thyroid cancer. Therefore, Nrf2 appears to be a potential therapeutic target for the treatment of thyroid cancer. This review summarized current data on Nrf2 expression in thyroid cancer, discussed the function of Nrf2 in thyroid cancer, and analyzed various strategies to inhibit Nrf2.

The effect of lipid metabolism on cuproptosis-inducing cancer therapy

Cuproptosis provides a new therapeutic strategy for cancer treatment and is thought to have broad clinical application prospects. Nevertheless, some oncological clinical trials have yet to demonstrate favorable outcomes, highlighting the need for further research into the molecular mechanisms underlying cuproptosis in tumors. Cuproptosis primarily hinges on the intracellular accumulation of copper, with lipid metabolism exerting a profound influence on its course. The interaction between copper metabolism and lipid metabolism is closely related to cuproptosis. Copper imbalance can affect mitochondrial respiration and lipid metabolism changes, while lipid accumulation can promote copper uptake and absorption, and inhibit cuproptosis induced by copper. Anomalies in lipid metabolism can disrupt copper homeostasis within cells, potentially triggering cuproptosis. The interaction between cuproptosis and lipid metabolism regulates the occurrence, development, metastasis, chemotherapy drug resistance, and tumor immunity of cancer. Cuproptosis is a promising new target for cancer treatment. However, the influence of lipid metabolism and other factors should be taken into consideration. This review provides a brief overview of the characteristics of the interaction between cuproptosis and lipid metabolism in cancer and analyses potential strategies of applying cuproptosis for cancer treatment.

SIRT1-NRF2-TFEB axis-mediated hepatic lipophagy alleviates the lipid deposition induced by high glucose in yellow catfish Pelteobagrus fulvidraco

Metabolic stress induces lipophagy, a crucial process in lipid catabolism, which is under the regulation of autophagy involving transcription factor EB (TFEB). However, the precise mechanisms underlying TFEB's control remain enigmatic. In this study, we focused on yellow catfish (Pelteobagrus fulvidraco) as the model to investigate lipophagy activation under high glucose-induced lipid deposition. We hypothesized that lipophagy mediates high glucose-induced lipid deposition and proposed the involvement of the SIRT1-NRF2-TFEB pathway in the activation of lipophagy. We found that there was a functional antioxidative responsive element (ARE) on the tfeb gene promoter; high glucose (HG) increased the nuclear translocation of nuclear factor E2-related factor 2 (NRF2) recruitment to the tfeb promoter; TFEB, whose expression is regulated by NRF2, mediated the HG-induced activation of lipophagy and lipolysis. Moreover, we found that HG increased the silencing information regulator 2 related enzymes 1 (SIRT1) expression, and that the SIRT1 mediates NRF2 translocation to the nucleus, increased TFEB expression and activated autophagy. In the glucose tolerance test, blood glucose increased rapidly and plateaued at 4-h glucose after injection and then declined until 48-h post-injection. Generally speaking, the transcript level and protein expression of SIRT1, NRF2, TFEB, microtubule-associated proteins 1A/1B light chain 3B (LC3B), and autophagy-related 6 (Beclin1) showed similar trend after glucose injection, and trends to increase and plateau at 4-h injection, then decline until 16-h post-injection, and finally increased until 48-h post-injection. These results indicated that the SIRT1-NRF2-TFEB axis-mediated lipophagy may be an adaptive response to glucose injection. Collectively, for the first time, we found that NRF2 was associated directly with TFEB-mediated transcriptional control of hepatic lipophagy, and that lipophagy helps to alleviate the HG-induced lipid deposition via SIRT1-NRF2-TFEB activation in yellow catfish.

Comparative subchronic toxicity of copper and a tertiary copper mixture to early life stage rainbow trout (Oncorhynchus mykiss): impacts on growth, development, and histopathology

This research aimed to characterize and compare the subchronic impacts of Cu to a Cu, Cd, and Zn mixture in early life stages of rainbow trout (Oncorhynchus mykiss) by examining uptake, survival, growth, development, and histopathology parameters. To accomplish this, rainbow trout were exposed for 31 days from eyed embryos to the swim-up fry life stage to waterborne Cu (31, 47, 70, and 104 μg/L) individually or as mixture containing Cd (4.1, 6.2, 9.3, and 14 μg/L) and Zn (385, 578, 867, and 1300 μg/L). Exposures elicited pronounced effects on survival when Cu was administered as a mixture (LC25 = 32.9 μg/L Cu) versus individually (LC25 = 46.3 μg/L Cu). Mixtures of Cu, Cd, and Zn also elicited more pronounced sublethal toxicity relative to equivalent Cu treatments with respect to reduced yolk sac resorption and increased incidence and/or severity of gill, liver, and kidney lesions. Our findings of reduced body weight (EC10, Cu = 55.0 μg/L Cu; EC10, Cu+Cd+Zn = 58.9 μg/L Cu), yolk sac resorption (LOECCu = 70 μg/L Cu; LOECCu+Cd+Zn = 70 μg/L Cu), coelomic fat (LOECCu = 47 μg/L Cu; LOECCu+Cd+Zn = 70 μg/L Cu), and increased hepatocellular cytoplasmic vacuolation (LOECCu = 70 μg/L Cu; LOECCu+Cd+Zn = 47 μg/L Cu) collectively indicate a complicated metabolic interference by metals in exposed fish. These lethal and sublethal effects observed in the laboratory could translate to reduced survival and fitness of wild salmonid populations inhabiting waterbodies receiving wastewater or runoff containing multiple metals at elevated concentrations.

Research into the anti-pulmonary fibrosis mechanism of Renshen Pingfei formula based on network pharmacology, metabolomics, and verification of AMPK/PPAR-γ pathway of active ingredients

ETHNOPHARMACOLOGICAL RELEVANCE

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with limited therapy. Renshen Pingfei Formula (RPFF), a classic Chinese medicine derivative formula, has been shown to exert therapeutic effects on IPF.

AIM OF THE STUDY

The study aimed to explore the anti-pulmonary fibrosis mechanism of RPFF through network pharmacology, clinical plasma metabolomics, and in vitro experiment.

METHODS

Network pharmacology was used to study the holistic pharmacological mechanism of RPFF in the treatment of IPF. The differential plasma metabolites for RPFF in the treatment of IPF were identified by untargeted metabolomics analysis. By integrated analysis of metabolomics and network pharmacology, the therapeutic target of RPFF for IPF and the corresponding herbal ingredients were identified. In addition, the effects of the main components of the formula, kaempferol and luteolin, which regulate the adenosine monophosphate (AMP)-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor γ (PPAR-γ) pathway were observed in vitro according to the orthogonal design.

RESULTS

A total of 92 potential targets for RPFF in the treatment of IPF were obtained. The Drug-Ingredients-Disease Target network showed that PTGS2, ESR1, SCN5A, PPAR-γ, and PRSS1 were associated with more herbal ingredients. The protein-protein interaction (PPI) network identified the key targets of RPFF in IPF treatment, including IL6, VEGFA, PTGS2, PPAR-γ, and STAT3. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis acquired the main enriched pathways, and PPAR-γ involved in multiple signaling pathways, including the AMPK signaling pathway. Untargeted clinical metabolomics analysis revealed plasma metabolite variations in patients with IPF versus controls and before versus after RPFF treatment for patients with IPF. Six differential metabolites were explored as differential plasma metabolites for RPFF in IPF treatment. Combined with network pharmacology, a therapeutic target PPAR-γ of RPFF in IPF treatment and the corresponding herbal components were identified. Based on the orthogonal experimental design, the experiments showed that kaempferol and luteolin can decrease the mRNA and protein expression of α-smooth muscle actin (α-SMA), and the combination of lower dose can inhibit α-SMA mRNA and protein expression by promoting the AMPK/PPAR-γ pathway in transforming growth factor beta 1 (TGF-β1)-treated MRC-5 cells.

CONCLUSIONS

This study revealed that the therapeutic effects of RPFF are due to multiple ingredients and have multiple targets and pathways, and PPAR-γ is one of therapeutic targets for RPPF in IPF and involved in the AMPK signaling pathway. Two ingredients of RPFF, kaempferol and luteolin, can inhibit fibroblast proliferation and the myofibroblast differentiation of TGF-β1, and exert a synergistic effect through AMPK/PPAR-γ pathway activation.

Serum levels of anti-inflammatory/proinflammatory adipocytokines, and copper levels in overweight and obese women in an adult Mexican population

BACKGROUND

An imbalance between adipokines and micronutrient concentrations, such as those of copper (Cu), has been linked to dysregulation of energy homeostasis leading to weight gain and the development of other comorbidities; however, information on this issue remains limited. Our aim was to investigate the correlation between Cu status and serum adipokine levels and their relationship in normal-weight, overweight, and obese adult women.

METHODS

Sixty patients were evaluated and classified according to their body mass index (BMI) and biochemical parameters; adipokines and Cu were measured at fasting.

RESULTS

Leptin (Lep) and resistin (Res) levels were elevated, whereas adiponectin (Adpn) and ghrelin (Ghr) values were decreased in overweight and obese women (p = 0.001). The mean Adpn/Lep ratio was <0.5 in overweight and obese subjects, while the Lep/Ghr ratio increased significantly in relation to weight gain, suggesting an inverse link between the ratios of these hormones in the regulation of obesity. The analysis revealed a positive association between BMI and Cu levels in obese women. Moreover, a negative association between Cu and Res in normal-weight subjects was found.

CONCLUSIONS

Circulating fasting Res levels are negatively associated with serum Cu concentration in normal-weight adult women. We also observed a close relationship between Adpn/Lep and Lep/Ghr ratios with obesity. However, more observational studies are required to confirm these results in future research.

Melatonin and ferroptosis: Mechanisms and therapeutic implications

Ferroptosis, a regulated form of cell death, is characterized by iron-dependent lipid peroxidation leading to oxidative damage to cell membranes. Cell sensitivity to ferroptosis is influenced by factors such as iron overload, lipid metabolism, and the regulation of the antioxidant system. Melatonin, with its demonstrated capacity to chelate iron, modulate iron metabolism proteins, regulate lipid peroxidation, and regulate antioxidant systems, has promise as a potential therapeutic agent in mediating ferroptosis. The availability of approved drugs targeting ferroptosis is limited; therefore, melatonin is a candidate for broad application due to its safety and efficacy in attenuating ferroptosis in noncancerous diseases. Melatonin has been demonstrated to attenuate ferroptosis in cellular and animal models of noncancerous diseases, showcasing effectiveness in organs such as the heart, brain, lung, liver, kidney, and bone. This review outlines the molecular mechanisms of ferroptosis, investigates melatonin's potential effects on ferroptosis, and discusses melatonin's therapeutic potential as a promising intervention against diseases associated with ferroptosis. Through this discourse, we aim to lay a strong foundation for developing melatonin as a therapeutic strategy to modulate ferroptosis in a variety of disease contexts.

Dexmedetomidine enables copper homeostasis in cerebral ischemia/reperfusion via ferredoxin 1

Excessive oxygen free radicals and toxic substances are generated in cerebral ischemia-reperfusion (I/R) process. Dexmedetomidine (DEX), a common anesthetic and sedative drug, can considerably boost glutathione (GSH), which has anti-copper influx effects. Focusing on cuproptosis, the mechanism of DEX in the I/R was revealed. Using the I/R rat model, the effects of DEX and the copper chelator D-penicillamine on cerebral infarct volume, copper levels, mitochondrial respiration and membrane potential, GSH content, and enrichment of cuproptosis functional proteins were examined. The involvement of ferredoxin 1 (FDX1) in the DEX regulatory pathway was verified by overexpressing FDX1 in vitro. DEX could significantly reduce cerebral infarction in rats, reduce copper levels, maintain mitochondrial functions, increase GSH, and reduce the content of key proteins related to cuproptosis. These aspects were replicated in vitro and revealed that FDX1 overexpression partially reversed the impacts of DEX. Together, cuproptosis occurs in the brain I/R process and DEX can enhance cell survival by blocking the primary pathway mediated by FDX1.KEY MESSAGESDexmedetomidine reduces cerebral infarction in the I/R rat models.Dexmedetomidine reduces cuproptosis in the I/R rat models.FDX1, an upstream of protein fatty acylation, mediates regulation of Dexmedetomidine.

Novel mechanism for zinc inducing hepatic lipolysis via the HDAC3-mediated deacetylation of β-catenin at lysine 311

Zinc (Zn) is a multipurpose trace element indispensable for vertebrates and possesses essential regulatory roles in lipid metabolism, but the fundamental mechanism remains largely unknown. In the current study, we found that a high-Zn diet significantly increased hepatic Zn content and influenced the expression of Zn transport-relevant genes. Dietary Zn addition facilitated lipolysis, inhibited lipogenesis, and controlled β-catenin signal; Zn also promoted T-cell factor 7-like 2 (TCF7L2) to interact with β-catenin and regulating its transcriptional activity, thereby inducing lipolysis and inhibiting lipogenesis; Zn-induced lipid degradation was mediated by histone deacetylase 3 (HDAC3) which was responsible for β-catenin deacetylation and the regulation of β-catenin signal under the Zn treatment. Mechanistically, Zn promoted lipid degradation via stimulating HDAC3-mediated deacetylation of β-catenin at lysine 311 (K311), which enhanced the interaction between β-catenin and TCF7L2 and then transcriptionally inhibited fatty acid synthase (FAS), 2-acylglycerol O-acyltransferase 2 (MOGAT2), and sterol regulatory element-binding protein 1 (SREBP1) expression, but elevated the mRNA abundance of adipose triglyceride lipase (ATGL), hormone-sensitive lipase a (HSLA) and carnitine palmitoyltransferase 1a1b (CPT1A1B). Overall, our research reveals a novel mechanism into the important roles of HDAC3/β-catenin pathway in Zn promoting lipolysis and inhibiting lipogenesis, and highlights the essential roles of K311 deacetylation in β-catenin actions and lipolytic metabolism, and accordingly provides novel insight into the prevention and treatment of steatosis in the vertebrates.

Identification and validation of potential diagnostic signature and immune cell infiltration for NAFLD based on cuproptosis-related genes by bioinformatics analysis and machine learning

Background and aims

Cuproptosis has been identified as a key player in the development of several diseases. In this study, we investigate the potential role of cuproptosis-related genes in the pathogenesis of nonalcoholic fatty liver disease (NAFLD).

Method

The gene expression profiles of NAFLD were obtained from the Gene Expression Omnibus database. Differential expression of cuproptosis-related genes (CRGs) were determined between NAFLD and normal tissues. Protein-protein interaction, correlation, and function enrichment analyses were performed. Machine learning was used to identify hub genes. Immune infiltration was analyzed in both NAFLD patients and controls. Quantitative real-time PCR was employed to validate the expression of hub genes.

Results

Four datasets containing 115 NAFLD and 106 control samples were included for bioinformatics analysis. Three hub CRGs (NFE2L2, DLD, and POLD1) were identified through the intersection of three machine learning algorithms. The receiver operating characteristic curve was plotted based on these three marker genes, and the area under the curve (AUC) value was 0.704. In the external GSE135251 dataset, the AUC value of the three key genes was as high as 0.970. Further nomogram, decision curve, calibration curve analyses also confirmed the diagnostic predictive efficacy. Gene set enrichment analysis and gene set variation analysis showed these three marker genes involved in multiple pathways that are related to the progression of NAFLD. CIBERSORT and single-sample gene set enrichment analysis indicated that their expression levels in macrophages, mast cells, NK cells, Treg cells, resting dendritic cells, and tumor-infiltrating lymphocytes were higher in NAFLD compared with control liver samples. The ceRNA network demonstrated a complex regulatory relationship between the three hub genes. The mRNA level of these hub genes were further confirmed in a mouse NAFLD liver samples.

Conclusion

Our study comprehensively demonstrated the relationship between NAFLD and cuproptosis, developed a promising diagnostic model, and provided potential targets for NAFLD treatment and new insights for exploring the mechanism for NAFLD.

Copper(II) Complexes with Carnosine Conjugates of Hyaluronic Acids at Different Dipeptide Loading Percentages Behave as Multiple SOD Mimics and Stimulate Nrf2 Translocation and Antioxidant Response in In Vitro Inflammatory Model

A series of copper(II) complexes with the formula [Cu2+Hy(x)Car%] varying the molecular weight (MW) of Hyaluronic acid (Hy, x = 200 or 700 kDa) conjugated with carnosine (Car) present at different loading were synthesized and characterized via different spectroscopic techniques. The metal complexes behaved as Cu, Zn-superoxide dismutase (SOD1) mimics and showed some of the most efficient reaction rate values produced using a synthetic and water-soluble copper(II)-based SOD mimic reported to date. The increase in the percentage of Car moieties parallels the enhancement of the I50 value determined via the indirect method of Fridovich. The presence of the non-functionalized Hy OH groups favors the scavenger activity of the copper(II) complexes with HyCar, recalling similar behavior previously found for the copper(II) complexes with Car conjugated using β-cyclodextrin or trehalose. In keeping with the new abilities of SOD1 to activate protective agents against oxidative stress in rheumatoid arthritis and osteoarthritis diseases, Cu2+ interaction with HyCar promotes the nuclear translocation of erythroid 2-related factor that regulates the expressions of target genes, including Heme-Oxigenase-1, thus stimulating an antioxidant response in osteoblasts subjected to an inflammatory/oxidative insult.

Exploring cuproptosis as a mechanism and potential intervention target in cardiovascular diseases

Copper (Cu) is a vital trace element for maintaining human health. Current evidence suggests that genes responsible for regulating copper influx and detoxification help preserve its homeostasis. Adequate Cu levels sustain normal cardiac and blood vessel activity by maintaining mitochondrial function. Cuproptosis, unlike other forms of cell death, is characterized by alterations in mitochondrial enzymes. Therapeutics targeting cuproptosis in cardiovascular diseases (CVDs) mainly include copper chelators, inhibitors of copper chaperone proteins, and copper ionophores. In this review, we expound on the primary mechanisms, critical proteins, and signaling pathways involved in cuproptosis, along with its impact on CVDs and the role it plays in different types of cells. Additionally, we explored the influence of key regulatory proteins and signaling pathways associated with cuproptosis on CVDs and determined whether intervening in copper metabolism and cuproptosis can enhance the outcomes of CVDs. The insights from this review provide a fresh perspective on the pathogenesis of CVDs and new targets for intervention in these diseases.

The emerging role of copper in depression

Copper (Cu) is an essential trace element in the brain and serves as an important cofactor for numerous enzymes involved in a wide range of biochemical processes including neurobehavioral, mitochondrial respiration, and antioxidant effects. Recent studies have demonstrated that copper dyshomeostasis is tightly associated with the development of depression by inducing oxidative stress and inflammatory responses. However, these findings have remained controversial so far. Cumulative studies have shown a positive association, while some other studies showed no association and even a negative association between serum/plasma copper level and depression. Based on these conflicted results, the association was speculated to be due to the clinical features of the population, stages of the disease, severity of copper excess, and types of specimens detected in these studies. In addition, there was an inverse association between dietary copper intake and depression. Furthermore, increasing copper intake could influence dietary zinc and iron intake to prevent and treat depression. Thus, copper supplementation may be a good measure to manage depression. This review provided a deeper understanding of the potential applicability of copper in the prevention and treatment of depression.

Copper induces liver lipotoxicity disease by up-regulating Nrf2 expression via the activation of MTF-1 and inhibition of SP1/Fyn pathway

Excessive copper (Cu) intake leads to hepatic lipotoxicity disease, which has adverse effects on health, but the underlying mechanism is unclear. We found that Cu increased lipotoxicity by promoting Nrf2 recruitment to the ARE site in the promoters of five lipogenic genes (g6pd, 6pgd, me, icdh and pparγ). We also found that Cu affected the Nrf2 expression via different pathways: metal regulatory transcription factor 1 (MTF-1) mediated the Cu-induced Nrf2 transcriptional activation; Cu also enhanced the expression of Nrf2 by inhibiting the SP1 expression, which was achieved by inhibiting the negative regulator Fyn of Nrf2. These promoted the enrichment of Nrf2 in the nucleus and ultimately affected lipotoxicity. Thus, for the first time, we elucidated that Cu induced liver lipotoxicity disease by up-regulating Nrf2 expression via the MTF-1 activation and the inhibition of SP1/Fyn pathway. Our study elucidates the Cu-associated obesity and NAFLD for fish and possibly humans.

Exposure to acute waterborne cadmium caused severe damage on lipid metabolism of freshwater fish, revealed by nuclear lipid droplet deposition in hepatocytes of rare minnow

Cadmium (Cd) is a widely distributed aquatic toxic heavy metal with the potential to disrupt fish metabolism; however, more research is needed to clarify the underlying mechanisms. In the present study, rare minnows (Gobiocypris rarus) were used to detect the effects of cadmium on freshwater fish lipid metabolism and its underlying mechanism by histopathological observation, measurement of serum and liver biochemical indexes, and analysis of gene expression in terms of lipid oxidation, synthesis and transport. Here, severe damage, such as cytoplasmic lipid droplet (LD) accumulation, ectopic deposition of LDs, and the appearance of nuclear LDs (nLDs), was detected after exposure to 2.0 mg/L or higher concentrations (2.5 and 2.8 mg/L CdCl₂) for 96 h. Other damage included abnormal increases in rough endoplasmic reticulum (RER) lamellae in a fingerprint or concentric circle pattern and necrosis of hepatocytes, and which was observed in the livers of fish exposed to 2.0 mg/L CdCl_2.. Both hepatic and serum lipids, such as triglycerides and total cholesterol, were significantly increased after exposure to 2.0 mg/L CdCl₂, as was serum lipase (LPS). Hepatic lipase and lipoprotein lipase remained unchanged, in accordance with the unchanged hepatic mRNA transcripts of PPARɑ. Furthermore, the mRNA transcripts of both SCD and SQLE were significantly decreased. Moreover, hepatic and serum low-density and high-density lipoprotein cholesterol showed significant changes, which were accompanied by a significant increase and decrease in hepatic APOAI and APOB100 mRNA levels, respectively. All the results indicate the presence of severe damage to hepatic lipid metabolism and that disrupted lipid transport may play a key role in the accumulation of hepatic LDs. In addition, the hepatic nLDs of nonmammalian vertebrates and their location across the nuclear envelope are intriguing, suggesting that large-size nLDs are a common marker for severe liver damage.

Copper-induced Genotoxicity, Oxidative Stress, and Alteration in Transcriptional Level of Autophagy-associated Genes in Snakehead Fish Channa punctatus

Copper (Cu) is an essential and important trace element for some significant life processes for most organisms. However, an excessive amount of Cu can be highly toxic. The present study was conducted to elucidate the oxidative stress-induced alteration in transcriptional level of autophagy-related genes in the liver and kidney tissue of fish Channa punctatus after treatment with three different sublethal concentrations of CuSO₄ for 28 days. All the studied enzymatic and non-enzymatic oxidative stress markers viz. superoxide dismutase-SOD, catalase-CAT, glutathione peroxidase-GPx, glutathione reductase-GR, and glutathione-GSH showed an increase in their activity levels in the treated groups in a dose-dependent manner. Particularly SOD and CAT have shown a significant hike in activity levels. ROS levels in blood cells increased significantly (p < 0.05) in all the treated groups, i.e., Group II-1/20^th of 96 h-LC₅₀ (0.2 mg/L), Group III-1/10^th of 96 h-LC₅₀ (0.4 mg/L), and Group IV-1/5 ^h of 96 h-LC₅₀ (0.8 mg/L) of Cu²⁺ in a dose-dependent manner as compared to control (Group I). The upregulation in mRNA levels of autophagy-related genes Microtubule-associated protein 1 light chain 3 (LC3), Gamma-aminobutyric acid receptor-associated protein precursor (Gabarap), and Golgi-associated ATPase enhancer of 16 kDa (GATE16), autophagy-related 5 (ATG5) was observed while mammalian target of rapamycin (mTOR) showed downregulation in the liver and kidney tissue of fish. The decrease in mTOR and increase in ATG5 gene expression projects autophagic vesicle formation due to oxidative stress. There was significant induction in micronuclei (MN) frequency in all the treated groups. The highest frequency of MN induced by Cu²⁺ was recorded in Group IV after 28 days of the exposure period. Thus, it can be concluded that the available information about Cu²⁺-induced oxidative stress-mediated autophagy in the liver and kidney of fish C. punctatus remains largely unclear to date, so to fill the aforesaid gap, the present study was undertaken, which gives an insight for the mechanisms of autophagy induced by Cu²⁺ in fish.

Sciadonic acid attenuates high-fat diet-induced obesity in mice with alterations in the gut microbiota

Obesity has been reported to be associated with dysbiosis of gut microbiota. Sciadonic acid (SC) is one of the main functional components of Torreya grandis "Merrillii" seed oil. However, the effect of SC on high-fat diet (HFD)-induced obesity has not been elucidated. In this study, we evaluated the effects of SC on lipid metabolism and the gut flora in mice fed with a high-fat diet. The results revealed that SC activates the PPARα/SREBP-1C/FAS signaling pathway and reduces the levels of total cholesterol (TC), triacylglycerols (TG), and low-density lipoprotein cholesterol (LDL-C), but increases the level of high-density lipoprotein cholesterol (HDL-C) and inhibits weight gain. Among them, high-dose SC was the most effective; the TC, TG and LDL-C levels were reduced by 20.03%, 28.40% and 22.07%, respectively; the HDL-C level was increased by 8.55%. In addition, SC significantly increased glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) levels by 98.21% and 35.17%, respectively, decreased oxidative stress, and ameliorated the pathological damage to the liver caused by a high-fat diet. Furthermore, SC treatment altered the composition of the intestinal flora, promoting the relative abundance of beneficial bacteria such as Lactobacillus and Bifidobacterium, while simultaneously decreasing the relative abundance of potentially harmful bacteria such as Faecalibaculum, norank_f_Desulfovibrionaceae, and Romboutsia. Spearman's correlation analysis indicated that the gut microbiota was associated with SCFAs and biochemical indicators. In summary, our results suggested that SC can improve lipid metabolism disorders and regulate the gut microbial structure.

Using native fish in eco-genotoxic assessment of heavy metal contamination pollution arising from nearby large Brazilian rivers

Worldwide water quality has declined progressively due to continuous pollution of aquatic resources by agrochemicals in particular heavy metals. Fish genotoxicity biomarkers are vital to identify and complement chemical parameters for determining environmental risk of adverse effects. Therefore, it was of interest to examine the eco-genotoxicity attributed to water pollution over different stream sections of Brazilian rivers by using Cichlasoma paranaense (Teleostei: Cichlidae), a neotropical freshwater cichlid fish, as a biological model. Chemical analysis of water and sediments collected from different Brazilian rivers sites demonstrated contamination by metals. Cichlasoma paranaense were collected at a reference location (a permanent water preservation area), maintained in the lab under standard conditions (controlled temperature, lighting, daily feeding, and constant aeration) and exposed to environmental samples of water and sediments. Subsequently, micronucleus (MN) and nuclear abnormalities (NA) frequencies were assessed in erythrocytes obtained from the caudal and gill regions. The highest concentrations of Cu were found in samples from river sites with forest fragmentation attributed to intensive agriculture practices. Similarly, exposure of fish to samples from agricultural areas induced significantly higher number of genotoxic effects. There was no marked difference between the tissues (tail and gill) regarding the observed frequencies of MN and NA. Thus C. paranaense fish served as a reliable model for detecting genotoxic effects, especially when water samples were collected near the discharge of agrochemicals. Evidence indicates that this method be considered for other global river sites which are also exposed to agrochemicals discharges containing Cu.

Comparison of copper concentration between non-alcoholic fatty liver disease patients and normal individuals: A meta-analysis

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease worldwide. Copper metabolism plays an important role in the pathogenesis of NAFLD. However, the relationship between serum/hepatic copper concentration and NAFLD is still debated. A literature search was performed using electronic databases to find publications up to September 2022, where the relationship between serum/hepatic copper or ceruloplasmin concentration and NAFLD was evaluated. Finally, 6 articles with 9 unique outcomes involving 2,607 NAFLD patients and 1,441 non-NAFLD normal individuals were included. The pooled results showed that hepatic copper concentration was significantly decreased in NAFLD patients (SMD = -0.98, 95% CI = [-1.21; -0.74], p < 0.0001), and the sensitivity analysis also confirmed this. Nevertheless, serum copper (SMD = -0.02, 95% CI = [-0.32; 0.28], p = 0.88) and ceruloplasmin (SMD = -0.03, 95% CI = [-0.69; 0.63], p = 0.93) were not associated with NAFLD. This meta-analysis revealed that low hepatic copper concentration was found in NAFLD patients and serum copper and ceruloplasmin were not associated with NAFLD. Larger cohort studies and related trials are needed to further validate the result of this meta-analysis in the future.

Lead and copper led to the dysregulation of bile acid homeostasis by impairing intestinal absorption in Bufo gargarizans larvae: An integrated metabolomics and transcriptomics approach

Bile acids, as metabolic regulators and signaling molecules, play key roles in the regulation of host metabolism and immune responses. Heavy metals such as lead (Pb) and copper (Cu) are widespread environmental pollutants that threaten public health. However, the effects of heavy metals on bile acid metabolism and the underlying molecular mechanisms remain unclear, particularly for ecologically important amphibian species. In the present research, the effects of exposure to environmentally-relevant concentrations of Pb (250 μg/L), Cu (50 μg/L), and a mixture of both (Mix) on bile acid metabolism and the underlying molecular mechanisms in the intestines of Bufo gargarizans larvae were comprehensively investigated using histopathology, metabolomics and transcriptomics analysis. Our results suggested that Pb and/or Cu caused histopathological damage to the intestine and liver, such as decreased intestinal epithelial cell height and dilated hepatic sinusoid. The total bile acid level was decreased in the Pb and Mix exposure groups but elevated in the Cu treatment. A significant decrease in the ratio of conjugated to unconjugated bile acids was present in all treatment groups. Also, the level of GCA was increased while TCA and TCDCA were decreased in all exposure groups. In addition, exposure to Pb and Cu altered the expression levels of genes related to intestinal absorption. For example, mrp2, mrp3 and aqp4 had higher expression in the Pb and Mix treatment groups, and aqp1 and mrp4 were increased in the Cu treatment group. Overall, we speculated that the dysregulation of bile acid homeostasis induced by Pb and Cu exposure may be due to impaired intestinal absorption. These findings raise further concerns about the hazards of Pb and/or Cu in influencing bile acid metabolism that might lead to the development of metabolic diseases and inflammatory disorders.

Comprehensive analysis of cuproptosis-related genes on bladder cancer prognosis, tumor microenvironment invasion, and drug sensitivity

Cuproptosis, a newly discovered form of programmed cell death, plays a vital role in the occurrence and development of tumors. However, the role of cuproptosis in the bladder cancer tumor microenvironment remains unclear. In this study, we developed a method for predicting the prognostic outcomes and guiding the treatment selection for patients with bladder cancer. We obtained 1001 samples and survival data points from The Cancer Genome Atlas database and Gene Expression Omnibus database. Using cuproptosis-related genes (CRGs) identified in previous studies, we analyzed CRG transcriptional changes and identified two molecular subtypes, namely high- and low-risk patients. The prognostic features of eight genes (PDGFRB, COMP, GREM1, FRRS1, SDHD, RARRES2, CRTAC1, and HMGCS2) were determined. The CRG molecular typing and risk scores were correlated with clinicopathological features, prognosis, tumor microenvironment cell infiltration characteristics, immune checkpoint activation, mutation burden, and chemotherapy drug sensitivity. Additionally, we constructed an accurate nomogram to improve the clinical applicability of the CRG_score. qRT-PCR was used to detect the expression levels of eight genes in bladder cancer tissues, and the results were consistent with the predicted results. These findings may help us to understand the role of cuproptosis in cancer and provide new directions for the design of personalized treatment and prediction of survival outcomes in patients with bladder cancer.

Dietary Choline Mitigates High-Fat Diet-Impaired Chylomicrons Assembly via UPRer Modulated by perk DNA Methylation

High-fat diets (HFD) lead to impairment of chylomicrons (CMs) assembly and adversely influence intestinal lipid homeostasis. However, the mechanisms of HFD impairing CMs assembly have yet to be fully understood. Additionally, although choline, as a lipid-lowering agent, has been widely used and its deficiency has been closely linked to non-alcoholic steatohepatitis (NASH), the contribution of choline by functioning as a methyl donor in alleviating HFD-induced intestinal lipid deposition is unknown. Thus, this study was conducted to determine the mechanism of HFD impairing CMs assembly and also tested the effect of choline acting as a methyl donor in this process. To this end, in this study, four diets (control, HFD, choline and HFD + choline diet) were fed to yellow catfish for 10 weeks in vivo and their intestinal epithelial cells were isolated and incubated for 36 h in fatty acids (FA) with or without choline solution combining si-perk transfection in vitro. The key findings from this study as follows: (1) HFD caused impairment of CMs assembly main by unfolded protein response (UPRer). HFD activated perk and then induced UPRer, which led to endoplasmic reticulum dysfunction and further impaired CMs assembly via protein-protein interactions between Perk and Apob48. (2) Choline inhibited the transcriptional expression level of perk via activating the -211 CpG methylation site, which initiated the subsequent ameliorating effect on HFD-impaired CMs assembly and intestinal lipid dysfunction. These results provide a new insight into direct crosstalk between UPRer and CMs assembly, and also emphasize the critical contribution of choline acting as a methyl donor and shed new light on choline-deficient diet-induced NASH.

The therapeutic potential of natural products for treating pancreatic cancer

Pancreatic cancer is one of the most malignant tumors of the digestive tract, with the poor prognosis and low 5-year survival rate less than 10%. Although surgical resection and chemotherapy as gemcitabine (first-line treatment) has been applied to the pancreatic cancer patients, the overall survival rates of pancreatic cancer are quite low due to drug resistance. Therefore, it is of urgent need to develop alternative strategies for its treatment. In this review, we summarized the major herbal drugs and metabolites, including curcumin, triptolide, Panax Notoginseng Saponins and their metabolites etc. These compounds with antioxidant, anti-angiogenic and anti-metastatic activities can inhibit the progression and metastasis of pancreatic cancer. Expecting to provide comprehensive information of potential natural products, our review provides valuable information and strategies for pancreatic cancer treatment.

Effects of Copper Exposure on Oxidative Stress, Apoptosis, Endoplasmic Reticulum Stress, Autophagy and Immune Response in Different Tissues of Chinese Mitten Crab (Eriocheir sinensis)

High concentrations of copper (Cu²⁺) pose a great threat to aquatic animals. However, the mechanisms underlying the response of crustaceans to Cu²⁺ exposure have not been well studied. Therefore, we investigated the alterations of physiological and molecular parameters in Chinese mitten crab (Eriocheir sinensis) after Cu²⁺ exposure. The crabs were exposed to 0 (control), 0.04, 0.18, and 0.70 mg/L of Cu²⁺ for 5 days, and the hemolymph, hepatopancreas, gills, and muscle were sampled. The results showed that Cu²⁺ exposure decreased the antioxidative capacity and promoted lipid peroxidation in different tissues. Apoptosis was induced by Cu²⁺ exposure, and this activation was associated with the mitochondrial and ERK pathways in the hepatopancreas. ER stress-related genes were upregulated in the hepatopancreas but downregulated in the gills at higher doses of Cu²⁺. Autophagy was considerably influenced by Cu²⁺ exposure, as evidenced by the upregulation of autophagy-related genes in the hepatopancreas and gills. Cu²⁺ exposure also caused an immune response in different tissues, especially the hepatopancreas, where the TLR2-MyD88-NF-κB pathway was initiated to mediate the inflammatory response. Overall, our results suggest that Cu²⁺ exposure induces oxidative stress, ER stress, apoptosis, autophagy, and immune response in E. sinensis, and the toxicity may be implicated following the activation of the ERK, AMPK, and TLR2-MyD88-NF-κB pathways.