COX5A Alleviates Doxorubicin-Induced Cardiotoxicity by Suppressing Oxidative Stress, Mitochondrial Dysfunction and Cardiomyocyte Apoptosis

Dexmedetomidine inhibits ferroptosis through the Akt/GSK3β/Nrf2 axis and alleviates adriamycin-induced cardiotoxicity

The cardiotoxicity of Adriamycin(ADR) limits its clinical application, and its molecular mechanism is not very clear. At present, Dexrazoxane (DXZ) is the only approved drug to prevent ADR-induced cardiotoxicity (DIC), but it also has serious adverse reactions. Therefore, it is a key scientific challenge to find a drug with strong myocardial protection, few adverse reactions and no effect on the anti-tumor effect of ADR. In this study, we established the DIC model in rats. Cardiomyocyte hypertrophy and myocardial fibrosis increased significantly, and MDA and LDH increased significantly in serum. Dexmedetomidine (DEX) is a carbohydrate with multiple biological activities that can significantly improve the above DIC process. Echocardiography confirmed that DEX could reverse the changes of ESV, EDV, EF and FS induced by ADR. In vitro, experiments confirmed that DEX reversed the upregulation of ANP, BNP, MHC and Collagen III protein levels induced by ADR. DEX improves DIC by inhibiting ferroptosis. Erastin, a ferroptosis agonist, confirmed that DEX improved DIC by inhibiting ferroptosis. Mechanically, DEX increases the expression of Nrf2 in the nucleus through the Akt/Gsk3β signalling axis, thereby regulating ferroptosis in cardiomyocytes. In addition, DEX can improve DIC while not affecting the anti-tumor effect of ADR.

Inhibition of GRK2 reduced doxorubicin-induced oxidative stress and apoptosis through upregulating ADH1

OBJECTIVE

Patients undergoing anti-cancer therapy with doxorubicin (DOX) face the risk of cumulative, irreversible cardiotoxicity. In failing hearts, the overexpressed and activated G protein-coupled receptor kinase 2 (GRK2) initiates pathological signaling, leading to cardiomyocyte death. This study aimed to investigate the potential role of GRK2 in DOX-induced cardiotoxicity (DIC).

METHODS

Mice were administered intraperitoneal injections of DOX (5 mg/kg) weekly for four weeks to induce DIC. Small interfering RNAs (siRNAs) targeting GRK2, ADH1, and PABPC1 were employed in H9c2 cells. Oxidative stress and cell apoptosis were assessed using Reactive Oxygen Species (ROS) staining and TUNEL staining, respectively. Co-immunoprecipitation (Co-IP) was utilized to detect the interaction between GRK2 and PABPC1. RNA immunoprecipitation (RIP) assay was employed to evaluate the binding between PABPC1 and ADH1 mRNA.

RESULTS

GRK2 was found to be upregulated in DOX-treated mouse hearts and H9c2 cells. Cardiomyocyte-specific GRK2 knockout partially mitigated oxidative stress, apoptosis, and cardiac dysfunction. Additionally, GRK2 knockdown attenuated DOX-induced oxidative damage and apoptosis both in vivo and in H9c2 cells. Furthermore, a reduction in ADH1 expression was observed in DOX-treated hearts and cardiomyocytes, with a pronounced increase following GRK2 knockdown. Notably, the beneficial effects of GRK2 knockdown in H9c2 cells were abolished after ADH1 knockdown. Mechanistically, GRK2 knockdown promoted the binding of PABPC1 to ADH1 mRNA, thereby inhibiting the degradation of ADH1 mRNA. Increased ADH1 expression alleviated DOX-induced oxidative stress and apoptosis in cardiomyocytes.

CONCLUSION

In conclusion, our study demonstrates that targeting GRK2 may represent a promising therapeutic strategy for mitigating DOX-associated cardiotoxicity.

Design, synthesis and biological evaluation of buthutin derivatives as cardioprotective agents

Natural products are the important sources in cardiovascular drug development. In this study, twenty-nine buthutin derivatives were designed, synthesized, and evaluated for their NHE-1 inhibition and protective effects on cardiomyocyte injury. The structure of the newly synthesized compounds had been confirmed by 1H-NMR, 13C-NMR, and HR-ESI-MS spectra. Among all target compounds at 1 μM, compounds 9d, 9f, 9k, 9m, and 9n, with a protection ratio exceeding 30%, exerted stronger protective effects on H9c2 cardiomyocyte than positive control dexrazoxane and buthutin A. Meanwhile, compounds 9k, 9m, and 9o showed the significant NHE-1 inhibitory activities on H9c2 cardiomyocyte, all with a dpHi/min value less than 0.23. What is more, compounds 9k, 9m, 9o and buthutin A all exhibited the specificity on NHE-1 inhibition. Molecular modelling studies suggested the ability of compounds 9m and 9o to establish interactions with three hydrogen bonds to Asp267 and Glu346 of NHE-1, but also the ability with much lower CDOCKER energies than positive control cariporide and buthutin A. The structure-activity relationship (SAR) studies suggested that the presences of amide group, four-carbon linker, and para hydroxyl benzene ring were advantageous pharmacophores for above two pharmacological actions. This research would open new avenues for developing amide-guanidine-based cardioprotective agents.

High mRNA Expression of 24 Dehydrocholesterol Reductase (DHCR24) in the Treatment of Doxorubicin-Induced Heart Failure in Rats

OBJECTIVE

The objective of this study was to explore the possibility of treating heart failure in rats by delivering mRNA of 24-dehydrocholesterol reductase (DHCR24) into the body through lipid nanoparticles (LNPs).

METHODS

We established a heart failure rat model using doxorubicin. The experiment was divided into blank, model, mRNA stock solution cardiac injection, mRNA stock solution intravenous injection, LNP-mRNA stock solution cardiac injection, and LNP-mRNA stock solution intravenous injection groups. We directly injected DHCR24-mRNA or LNP-DHCR24-mRNA into the myocardium in three regions through an insulin needle passing through the intercostal space under the guidance of B-ultrasound. We recorded the mortality rate, body weight, 6-min walk test return times, and organ weight of rats after administration and detected the cardiac structure and function using B-ultrasound and transmission electron microscopy (TEM). Additionally, we tested for HE staining; PRDX2, Sirt3, and TRX1 protein expression; and IL-1 β, IL-10, VEGF, NT proBNP, and BNP cytokine concentrations.

RESULTS

Compared with the model group, the administration of DHCR24-mRNA significantly reduced mortality; decreased weight loss, the ratio of heart to tibia length, and spleen weight; and improved rat motility. The administration of DHCR24-mRNA can postpone the pathological morphological alterations of myocardial cells and reduce inflammatory infiltration. In terms of biochemistry, the administration of DHCR24-mRNA can increase the expression of the PRDX2, Sirt3, and TRX1 proteins; increase the concentrations of IL-10 and VEGF; and reduce the concentrations of IL-1β, NT proBNP, and BNP. The administration of DHCR24-mRNA can also delay the process of heart failure. The delivery and therapeutic effect of DHCR24-mRNA encapsulated in LNPs were better when compared to the other groups.

CONCLUSIONS

DHCR24-mRNA encapsulated in LNPs can be effectively administered to rats with heart failure and exhibits some curative effects.

Transcriptomic analysis reveals differentially expressed genes associated with meat quality in Chinese Dagu chicken and AA+ broiler roosters

BACKGROUND

With the improvement of living standards, the quality of chicken has become a significant concern. Chinese Dagu Chicken (dual-purpose type) and Arbor Acres plus broiler (AA+ broiler) (meat-type) were selected as the research subjects in this study, the meat quality of the breast and leg muscles were measured. However, the molecular mechanism(s) underlying regulation of muscle development are not yet fully elucidated. Therefore, finding molecular markers or major genes that regulate muscle quality has become a crucial breakthrough in chicken breeding. Unraveling the molecular mechanism behind meat traits in chicken and other domestic fowl is facilitated by identifying the key genes associated with these developmental events. Here, a comparative transcriptomic analysis of chicken meat was conducted on breast muscles (BM) and leg muscles (LM) in AA+ broilers (AA) and Dagu chicken (DG) to explore the differences in their meat traits employing RNA-seq.

RESULTS

Twelve cDNA libraries of BM and LM from AA and DG were constructed from four experimental groups, yielding 14,464 genes. Among them, Dagu chicken breast muscles (DGB) vs AA+ broilers breast muscles (AAB) showed 415 upregulated genes and 449 downregulated genes, Dagu chicken leg muscles (DGL) vs AA+ broilers leg muscles (AAL) exhibited 237 upregulated genes and 278 downregulated genes, DGL vs DGB demonstrated 391 upregulated genes and 594 downregulated genes, and AAL vs AAB displayed 122 upregulated genes and 154 downregulated genes. 13 genes, including nine upregulated genes (COX5A, COX7C, NDUFV1, UQCRFS1, UQCR11, BRT-1, FGF14, TMOD1, MYOZ2) and four downregulated genes (MYBPC3, MYO7B, MTMR7, and TNNC1), were found to be associated with the oxidative phosphorylation signaling pathway. Further analysis revealed that the differentially expressed genes (DEGs) from muscle were enriched in various pathways, such as metabolic pathways, oxidative phosphorylation, carbon metabolism, glycolysis, extracellular matrix-receptor interaction, biosynthesis of amino acids, focal adhesion, vascular smooth muscle contraction, and cardiac muscle contraction, all of which are involved in muscle development and metabolism. This study also measured the meat quality of the breast and leg muscles from the two breeds, which demonstrated superior overall meat quality in Chinese Dagu Chicken compared to the AA+ broiler.

CONCLUSIONS

Our findings show that the meat quality of dual-purpose breeds (Chinese Dagu chicken) is higher than meat-type (AA+ broiler), which may be related to the DEGs regulating muscle development and metabolism. Our findings also provide transcriptomic insights for a comparative analysis of molecular mechanisms underlying muscle development between the two breeds, and have practical implications for the improvement of chicken breeding practices.

Anthracycline-induced cardiotoxicity: An overview from cellular structural perspective

Anthracyclines are broad-spectrum anticancer drugs, but their clinical use is limited due to their severe cardiotoxicity. Anthracycline-induced cardiotoxicity (AIC) remains a significant cause of heart disease-related mortality in many cancer survivors. The underlying mechanisms of AIC have been explored over the past few decades. Reactive oxygen species and drug-induced inhibition of topoisomerase II beta are well-studied mechanisms, with mitochondria being a prominently investigated organelle. Emerging mechanisms such as ferroptosis, Ca2+ overload, autophagy and inflammation mediators have been implicated in recent years. In this review, our goal is to summarize and update the roles of various mechanisms in AIC, focusing on different cellular levels and further explore promising therapeutic approaches targeting these organelles or pathways.

Integrating genome- and transcriptome-wide association studies to uncover the host-microbiome interactions in bovine rumen methanogenesis

The ruminal microbiota generates biogenic methane in ruminants. However, the role of host genetics in modifying ruminal microbiota-mediated methane emissions remains mysterious, which has severely hindered the emission control of this notorious greenhouse gas. Here, we uncover the host genetic basis of rumen microorganisms by genome- and transcriptome-wide association studies with matched genome, rumen transcriptome, and microbiome data from a cohort of 574 Holstein cattle. Heritability estimation revealed that approximately 70% of microbial taxa had significant heritability, but only 43 genetic variants with significant association with 22 microbial taxa were identified through a genome-wide association study (GWAS). In contrast, the transcriptome-wide association study (TWAS) of rumen microbiota detected 28,260 significant gene-microbe associations, involving 210 taxa and 4652 unique genes. On average, host genetic factors explained approximately 28% of the microbial abundance variance, while rumen gene expression explained 43%. In addition, we highlighted that TWAS exhibits a strong advantage in detecting gene expression and phenotypic trait associations in direct effector organs. For methanogenic archaea, only one significant signal was detected by GWAS, whereas the TWAS obtained 1703 significant associated host genes. By combining multiple correlation analyses based on these host TWAS genes, rumen microbiota, and volatile fatty acids, we observed that substrate hydrogen metabolism is an essential factor linking host-microbe interactions in methanogenesis. Overall, these findings provide valuable guidelines for mitigating methane emissions through genetic regulation and microbial management strategies in ruminants.

Fluoride induces immunotoxicity by regulating riboflavin transport and metabolism partly through IL-17A in the spleen

The impairment of the immune system by fluoride is a public health concern worldwide, yet the underlying mechanism is unclear. Both riboflavin and IL-17A are closely related to immune function and regulate the testicular toxicity of fluoride. However, whether riboflavin or IL-17A is involved in fluoride-induced immunotoxicity is unknown. Here, we first established a male ICR mouse model by treating mice with sodium fluoride (NaF) (100 mg/L) via the drinking water for 91 days. The results showed that fluoride increased the expression of the proinflammatory factors IL-1β and IL-17A, which led to splenic inflammation and morphological injury. Moreover, the expression levels of the riboflavin transporters SLC52A2 and SLC52A3; the transformation-related enzymes RFK and FLAD1; and the key mitochondrial functional determinants SDH, COX, and ATP in the spleen were measured via real-time PCR, Western blotting, and ELISA. The results revealed that fluoride disrupted riboflavin transport, transformation, metabolism, and mitochondrial function. Furthermore, wild-type (WT) and IL-17A knockout (IL-17A-/-) C57BL/6 J male mice of the same age were treated with NaF (24 mg/kg·bw, equivalent to 100 mg/L) and/or riboflavin sodium phosphate (5 mg/kg·bw) via gavage for 91 days. Similar parameters were evaluated as above. The results confirmed that fluoride increased riboflavin metabolism through RFK but not through FLAD1. Fluoride also affected mitochondrial function and activated neutrophils (marked with Ly6g) and macrophages (marked with CD68) in the spleen. Interestingly, IL-17A partly mediated fluoride-induced riboflavin metabolism disorder and immunotoxicity in the spleen. This work not only reveals a novel toxic mechanism for fluoride but also provides new clues for exploring the physiological function of riboflavin and for diagnosing and treating the toxic effects of fluoride in the environment.

Research Progress on the Mechanism, Monitoring, and Prevention of Cardiac Injury Caused by Antineoplastic Drugs-Anthracyclines

Anthracyclines represent a highly efficacious class of chemotherapeutic agents employed extensively in antitumor therapy. They are universally recognized for their potency in treating diverse malignancies, encompassing breast cancer, gastrointestinal tumors, and lymphomas. Nevertheless, the accumulation of anthracyclines within the body can lead to significant cardiac toxicity, adversely impacting both the survival rates and quality of life for tumor patients. This limitation somewhat restricts their clinical utilization. Determining how to monitor and mitigate their cardiotoxicity at an early stage has become an urgent clinical problem to be solved. Therefore, this paper reviews the mechanism of action, early monitoring, and strategies for the prevention of anthracycline-induced cardiotoxicity for clinical reference.

AP39 through AMPK-ULK1-FUNDC1 pathway regulates mitophagy, inhibits pyroptosis, and improves doxorubicin-induced myocardial fibrosis

Doxorubicin induces myocardial injury and fibrosis. Still, no effective interventions are available. AP39 is an H2S donor that explicitly targets mitochondria. This study investigated whether AP39 could improve doxorubicin-induced myocardial fibrosis. Doxorubicin induced significant myocardial fibrosis while suppressing mitophagy-related proteins and elevating pyroptosis-related proteins. Conversely, AP39 reverses these effects, enhancing mitophagy and inhibiting pyroptosis. In vitro experiments revealed that AP39 inhibited H9c2 cardiomyocyte pyroptosis, improved doxorubicin-induced impairment of mitophagy, reduced ROS levels, ameliorated the mitochondrial membrane potential, and upregulated AMPK-ULK1-FUNDC1 expression. In contrast, AMPK inhibitor (dorsomorphin) and ULK1 inhibitor (SBI-0206965) reversed AP39 antagonism of doxorubicin-induced FUNDC1-mediated impairment of mitophagy and secondary cardiomyocyte pyroptosis. These results suggest that mitochondria-targeted H2S can antagonize doxorubicin-induced pyroptosis and impaired mitophagy in cardiomyocytes via AMPK-ULK1-FUNDC1 and ameliorated myocardial fibrosis and remodeling.

Type I interferon alters invasive extravillous trophoblast function

Inappropriate type I interferon (IFN) signaling during embryo implantation and placentation is linked to poor pregnancy outcomes. Here, we evaluated the consequence of elevated type I IFN exposure on implantation using a biomimetic model of human implantation in an organ-on-a-chip device. We found that type I IFN reduced extravillous trophoblast (EVT) invasion capacity. Analyzing single-cell transcriptomes, we uncovered that IFN truncated endovascular EVT emergence in the implantation-on-a-chip device by stunting EVT epithelial-to-mesenchymal transition. Disruptions to the epithelial-to-mesenchymal transition is associated with the pathogenesis of preeclampsia, a life-threatening hypertensive disorder of pregnancy. Strikingly, unwarranted IFN stimulation induced genes associated with increased preeclampsia risk and a preeclamptic gene-like signature in EVTs. These dysregulated EVT phenotypes ultimately reduced EVT-mediated endothelial cell vascular remodeling in the implantation-on-a-chip device. Overall, our work indicates IFN signaling can alter EVT epithelial-to-mesenchymal transition progression which results in diminished EVT-mediated spiral artery remodeling and a preeclampsia gene signature upon sustained stimulation. Our work implicates unwarranted type I IFN as a maternal disturbance that can result in abnormal EVT function that could trigger preeclampsia.

Lactate Can Modulate the Antineoplastic Effects of Doxorubicin and Relieve the Drug's Oxidative Damage on Cardiomyocytes

BACKGROUND

Doxorubicin (DOXO) is currently administered as the first-choice therapy for a variety of malignancies. Cancer cells exhibit enhanced glycolysis and lactate production. This metabolite affects gene expression and can play a role in chemoresistance.

AIM OF THIS STUDY

We investigated whether the enhanced lactate levels that characterize neoplastic tissues can modify the response of cancer cells to DOXO.

METHODS

After exposing cancer cells to increased lactate levels, we examined whether this metabolite could interfere with the principal mechanisms responsible for the DOXO antineoplastic effect.

RESULTS

Increased lactate levels did not affect DOXO-induced topoisomerase poisoning but offered protection against the oxidative damage caused by the drug. This protection was related to changes in gene expression caused by the combined action of DOXO and lactate. Oxidative damage significantly contributed to the heavy cardiotoxicity following DOXO treatment. In cultured cardiomyocytes, we confirmed that DOXO-induced DNA damage and oxidative stress can be significantly mitigated by exposing the cells to increased lactate levels.

CONCLUSIONS

In addition to contributing to elucidating the effects of the combined action of DOXO and lactate, our results suggest a possible method to reduce the heavy drug cardiotoxicity, a major side effect leading to therapy discontinuation.