Copper mediated follicular atresia: Implications for granulosa cell death.

3-nitropropanoic acid is a potent oxidative stress inducer that is conventionally regarded as a regulator of follicular atresia by regulating granulosa cells (GCs) death through the apoptosis pathway. There has been no research investigating the impact of copper metal overload induced Cuproptosis in ovarian GCs as a factor contributing to hindered follicular development.To elucidate whether 3-NP-induced oxidative stress plays a contributory role in promoting Cuproptosis, and discuss the role of Cuproptosis in the development of ovarian follicles.We conducted an analysis of cuproptosis occurrence in murine GCs and C57BL/6 J mice under the influence of 3-NP and 3-NP with added exogenous copper.The results revealed that 3-NP serving as a robust facilitator of exogenous copper uptake by upregulating the expression of copper transporter 1 (CTR1). In turn, culminated in the accumulation of intracellular copper within mouse granulosa cells (mGCs). Furthermore, 3-NP promoted mitochondrial permeability transition pore opening and concurrently reduced the stability of lipoic acid proteins. These actions collectively induced the oligomerization of Dihydrolipoamide S-Acetyltransferase (DLAT), ultimately leading to cuproptosis in GCs and consequent follicular atresia. Heavy metal copper and fungal decomposition product 3-NP, induce ovarian atresia via cuproptosis, modulating the reproductive performance of female animals.

PTPN2 copper-sensing relays copper level fluctuations into EGFR/CREB activation and associated CTR1 transcriptional repression.

Fluxes in human copper levels recently garnered attention for roles in cellular signaling, including affecting levels of the signaling molecule cyclic adenosine monophosphate. We herein apply an unbiased temporal evaluation of the signaling and whole genome transcriptional activities modulated by copper level fluctuations to identify potential copper sensor proteins responsible for driving these activities. We find that fluctuations in physiologically relevant copper levels modulate EGFR signal transduction and activation of the transcription factor CREB. Both intracellular and extracellular assays support Cu1+ inhibition of the EGFR phosphatase PTPN2 (and potentially PTPN1)-via ligation to the PTPN2 active site cysteine side chain-as the underlying mechanism. We additionally show i) copper supplementation drives weak transcriptional repression of the copper importer CTR1 and ii) CREB activity is inversely correlated with CTR1 expression. In summary, our study reveals PTPN2 as a physiological copper sensor and defines a regulatory mechanism linking feedback control of copper stimulated EGFR/CREB signaling and CTR1 expression.

[Research progress on regulatory mechanism of renal copper homeostasis].

Copper is a vital trace metal element necessary for the functioning of living organisms. It serves as a co-factor or structural component in numerous enzymes, participating in crucial biological metabolic processes. Disruptions in copper homeostasis, whether inherited or acquired, such as copper overload, deficiency, or uneven distribution, can contribute to or exacerbate various diseases, including Menkes disease, Wilson's disease, neurodegenerative disorders, anemia, cardiovascular diseases, kidney diseases and cancer. Recent research has highlighted the close correlation between chronic kidney disease and intracellular copper overload. Therefore, renal cells must establish a well-organized and efficient copper regulation network to maintain intracellular copper homeostasis. This review summarizes the processes of copper uptake, intracellular trafficking, storage, and excretion in renal cells, and elucidates the underlying mechanisms involved, aiming to provide a theoretical foundation and potential therapeutic targets for the fundamental investigation and clinical management of kidney-related diseases.

Revealing the potential of solute carrier family 31 (copper transporters), member 1: Insights into its role in bladder cancer progression and therapeutic implications.

Introduction: Bladder cancer represents a significant public health concern with diverse genetic alterations influencing disease onset, progression, and therapy response. In this study, we explore the multifaceted role of Solute Carrier Family 31 Member 1 (SLC31A1) in bladder cancer, a pivotal gene involved in copper homeostasis. Methods: Our research involved analyzing the SLC31A1 gene expression via RT-qPCR, promoter methylation via targeted bisulfite sequencing, and mutational status via Next Generation Sequencing (NGS) using the clinical samples sourced by the local bladder cancer patients. Later on, The Cancer Genome Atlas (TCGA) datasets were utilized for validation purposes. Moreover, prognostic significance, gene enrichment terms, and therapeutic drugs of SLC31A1 were also explored using KM Plotter, DAVID, and DrugBank databases. Results: We observed that SLC31A1 was significantly up-regulated at both the mRNA and protein levels in bladder cancer tissue samples, suggesting its potential involvement in bladder cancer development and progression. Furthermore, our investigation into the methylation status revealed that SLC31A1 was significantly hypomethylated in bladder cancer tissues, which may contribute to its overexpression. The ROC analysis of the SLC31A1 gene indicated promising diagnostic potential, emphasizing its relevance in distinguishing bladder cancer patients from normal individuals. However, it is crucial to consider other factors such as cancer stage, metastasis, and recurrence for a more accurate evaluation in the clinical context. Interestingly, mutational analysis of SLC31A1 demonstrated only benign mutations, indicating their unknown role in the SLC31A1 disruption. In addition to its diagnostic value, high SLC31A1 expression was associated with poorer overall survival (OS) in bladder cancer patients, shedding light on its prognostic relevance. Gene enrichment analysis indicated that SLC31A1 could influence metabolic and copper-related processes, further underscoring its role in bladder cancer. Lastly, we explored the DrugBank database to identify potential therapeutic agents capable of reducing SLC31A1 expression. Our findings unveiled six important drugs with the potential to target SLC31A1 as a treatment strategy. Conclusion: Our comprehensive investigation highlights SLC31A1 as a promising biomarker for bladder cancer development, progression, and therapy.

Nonsense-mediated mRNA decay of metal-binding activator MAC1 is dependent on copper levels and 3'-UTR length in Saccharomyces cerevisiae.

The nonsense-mediated mRNA decay (NMD) pathway was initially identified as a surveillance pathway that degrades mRNAs containing premature termination codons (PTCs). NMD is now also recognized as a post-transcriptional regulatory pathway that regulates the expression of natural mRNAs. Earlier studies demonstrated that regulation of functionally related natural mRNAs by NMD can be differential and condition-specific in Saccharomyces cerevisiae. Here, we investigated the regulation of MAC1 mRNAs by NMD in response to copper as well as the role the MAC1 3'-UTR plays in this regulation. MAC1 is a copper-sensing transcription factor that regulates the high-affinity copper uptake system. MAC1 expression is activated upon copper deprivation. We found that MAC1 mRNAs are regulated by NMD under complete minimal (CM) but escaped NMD under low and high copper conditions. Mac1 protein regulated gene, CTR1 is not regulated by NMD in conditions where MAC1 mRNAs are NMD sensitive. We also found that the MAC1 3'-UTR is the NMD targeting feature on the mRNAs, and that MAC1 mRNAs lacking 3'-UTRs were stabilized during copper deprivation. Our results demonstrate a mechanism of regulation for a metal-sensing transcription factor, at both the post-transcriptional and post-translational levels, where MAC1 mRNA levels are regulated by NMD and copper, while the activity of Mac1p is controlled by copper levels.

Protective effect of rosmarinic acid on the transmembrane transporter Ctr1 expression in cisplatin-treated mice.

AIMS: Cisplatin (cis-diamminedichloroplatinum(II), CP) is a platinum-based anticancer drug widely used in the treatment of solid malignancies. However, its side effects, particularly nephrotoxicity, are limiting factors in its clinic use. Rosmarinic acid (RA), a natural antioxidant compound, is reported to attenuate oxidative stress and associated pathophysiological outcomes. Our study aimed to explore the protective effect of RA against CP-induced acute kidney injury (AKI). MATERIALS AND METHODS: We investigated the effect of RA at the dose of 100 mg/kg on AKI induced by CP (20 mg/kg) in mice. Various parameters of nephrotoxicity such as levels of serum electrolytes, albumin, and globulin were measured using standardized methods. Besides, a specific biomarker of damage to proximal tubular cells, kidney injury molecule-1 (Kim-1), was measured in the serum by ELISA. mRNA expression of Kim-1 and a transmembrane transporter, copper transporter 1 (Ctr1), was analyzed by quantitative reverse transcriptase-polymerase chain reaction. CTR1 expression was also analyzed by western blot technique. RESULTS: RA treatment restored the downregulated CTR1 , a renal transmembrane transporter in CP-treated mice. It was accompanied by a reduction in the level of serum albumin and globulin. Serum electrolytes such as Na+, K+, and Ca2+ in CP-treated mice were found to be restored with RA treatment. Moreover, RA also significantly downregulated the increased expression of nephrotoxicity biomarker KIM-1. CONCLUSIONS: Overall, RA proved to be an effective nephroprotective compound which afforded protection at cellular and subcellular levels with an appreciable modulatory effect on a transmembrane transporter.

Research progress of copper transporter 1 in platinum-based chemotherapy / 中南大学学报(医学版)

Platinum drugs are widely used in the treatment of various solid tumors, but their resistance to platinum is the most significant obstacle to successful treatment. Copper transporter 1 (CTR1) is the specific transporter for copper, and it mainly locates at the plasma membrane and plays a role in pumping copper into the cell. CTR1 is also the major platinum influx transporter and plays a key role in platinum resistance. The expression, polymorphism, and degradation of CTR1 affect platinum resistance in tumors. Therefore, CTR1 may be a potential predictive biomarker of platinum resistance and a therapeutic target for overcoming platinum resistance.