Low-Dose Colchicine Ameliorates Doxorubicin Cardiotoxicity Via Promoting Autolysosome Degradation.

BACKGROUND: The only clinically approved drug that reduces doxorubicin cardiotoxicity is dexrazoxane, but its application is limited due to the risk of secondary malignancies. So, exploring alternative effective molecules to attenuate its cardiotoxicity is crucial. Colchicine is a safe and well-tolerated drug that helps reduce the production of reactive oxygen species. High doses of colchicine have been reported to block the fusion of autophagosomes and lysosomes in cancer cells. However, the impact of colchicine on the autophagy activity within cardiomyocytes remains inadequately elucidated. Recent studies have highlighted the beneficial effects of colchicine on patients with pericarditis, postprocedural atrial fibrillation, and coronary artery disease. It remains ambiguous how colchicine regulates autophagic flux in doxorubicin-induced heart failure. METHODS AND RESULTS: Doxorubicin was administered to establish models of heart failure both in vivo and in vitro. Prior studies have reported that doxorubicin impeded the breakdown of autophagic vacuoles, resulting in damaged mitochondria and the accumulation of reactive oxygen species. Following the administration of a low dose of colchicine (0.1 mg/kg, daily), significant improvements were observed in heart function (left ventricular ejection fraction: doxorubicin group versus treatment group=43.75%±3.614% versus 57.07%±2.968%, P=0.0373). In terms of mechanism, a low dose of colchicine facilitated the degradation of autolysosomes, thereby mitigating doxorubicin-induced cardiotoxicity. CONCLUSIONS: Our research has shown that a low dose of colchicine is pivotal in restoring the autophagy activity, thereby attenuating the cardiotoxicity induced by doxorubicin. Consequently, colchicine emerges as a promising therapeutic candidate to improve doxorubicin cardiotoxicity.

Beneficial Effects of Oral Carbon Monoxide on Doxorubicin-Induced Cardiotoxicity.

BACKGROUND: Doxorubicin and other anthracyclines are crucial cancer treatment drugs. However, they are associated with significant cardiotoxicity, severely affecting patient care and limiting dosage and usage. Previous studies have shown that low carbon monoxide (CO) concentrations protect against doxorubicin toxicity. However, traditional methods of CO delivery pose complex challenges for daily administration, such as dosing and toxicity. To address these challenges, we developed a novel oral liquid drug product containing CO (HBI-002) that can be easily self-administered by patients with cancer undergoing doxorubicin treatment, resulting in CO being delivered through the upper gastrointestinal tract. METHODS AND RESULTS: HBI-002 was tested in a murine model of doxorubicin cardiotoxicity in the presence and absence of lung or breast cancer. The mice received HBI-002 twice daily before doxorubicin administration and experienced increased carboxyhemoglobin levels from a baseline of ≈1% to 7%. Heart tissue from mice treated with HBI-002 had a 6.3-fold increase in CO concentrations and higher expression of the cytoprotective enzyme heme oxygenase-1 compared with placebo control. In both acute and chronic doxorubicin toxicity scenarios, HBI-002 protected the heart from cardiotoxic effects, including limiting tissue damage and cardiac dysfunction and improving survival. In addition, HBI-002 did not compromise the efficacy of doxorubicin in reducing tumor volume, but rather enhanced the sensitivity of breast 4T1 cancer cells to doxorubicin while simultaneously protecting cardiac function. CONCLUSIONS: These findings strongly support using HBI-002 as a cardioprotective agent that maintains the therapeutic benefits of doxorubicin cancer treatment while mitigating cardiac damage.

miRNA Expression Profiles in Isolated Ventricular Cardiomyocytes: Insights into Doxorubicin-Induced Cardiotoxicity.

Doxorubicin (DOX), widely used as a chemotherapeutic agent for various cancers, is limited in its clinical utility by its cardiotoxic effects. Despite its widespread use, the precise mechanisms underlying DOX-induced cardiotoxicity at the cellular and molecular levels remain unclear, hindering the development of preventive and early detection strategies. To characterize the cytotoxic effects of DOX on isolated ventricular cardiomyocytes, focusing on the expression of specific microRNAs (miRNAs) and their molecular targets associated with endogenous cardioprotective mechanisms such as the ATP-sensitive potassium channel (KATP), Sirtuin 1 (SIRT1), FOXO1, and GSK3ß. We isolated Guinea pig ventricular cardiomyocytes by retrograde perfusion and enzymatic dissociation. We assessed cell morphology, Reactive Oxygen Species (ROS) levels, intracellular calcium, and mitochondrial membrane potential using light microscopy and specific probes. We determined the miRNA expression profile using small RNAseq and validated it using stem-loop qRT-PCR. We quantified mRNA levels of some predicted and validated molecular targets using qRT-PCR and analyzed protein expression using Western blot. Exposure to 10 µM DOX resulted in cardiomyocyte shortening, increased ROS and intracellular calcium levels, mitochondrial membrane potential depolarization, and changes in specific miRNA expression. Additionally, we observed the differential expression of KATP subunits (ABCC9, KCNJ8, and KCNJ11), FOXO1, SIRT1, and GSK3ß molecules associated with endogenous cardioprotective mechanisms. Supported by miRNA gene regulatory networks and functional enrichment analysis, these findings suggest that DOX-induced cardiotoxicity disrupts biological processes associated with cardioprotective mechanisms. Further research must clarify their specific molecular changes in DOX-induced cardiac dysfunction and investigate their diagnostic biomarkers and therapeutic potential.

Cardioprotective potentials of myricetin on doxorubicin-induced cardiotoxicity based on biochemical and transcriptomic analysis.

Doxorubicin (DOX) is a commonly used anthracycline in cancer chemotherapy. The clinical application of DOX is constrained by its cardiotoxicity. Myricetin (MYR) is a natural flavonoid widely present in many plants with antioxidant and anti-inflammatory properties. However, MYR's beneficial effects and mechanisms in alleviating DOX-induced cardiotoxicity (DIC) remain unknown. C57BL/6 mice were injected with 15 mg/kg of DOX to establish the DIC, and MYR solutions were administrated by gavage to investigate its cardioprotective potentials. Histopathological analysis, physiological indicators assessment, transcriptomics analysis, and RT-qPCR were used to elucidate the potential mechanism of MYR in DIC treatment. MYR reduced cardiac injury produced by DOX, decreased levels of cTnI, AST, LDH, and BNP, and improved myocardial injury and fibrosis. MYR effectively prevented DOX-induced oxidative stress, such as lowered MDA levels and elevated SOD, CAT, and GSH activities. MYR effectively suppressed NLRP3 and ASC gene expression levels to inhibit pyroptosis while regulating Caspase1 and Bax levels to reduce cardiac cell apoptosis. According to the transcriptomic analysis, glucose and fatty acid metabolism were associated with differential gene expression. KEGG pathway analysis revealed differential gene enrichment in PPAR and AMPK pathways, among others. Following validation, MYR was found to alleviate DIC by regulating glycolipid metabolism and AMPK pathway-related genes. Our findings demonstrated that MYR could mitigate DIC by regulating the processes of oxidative stress, apoptosis, and pyroptosis. MYR is critical in improving DOX-induced myocardial energy metabolism abnormalities mediated by the AMPK signaling pathway. In conclusion, MYR holds promise as a therapeutic strategy for DIC.

Dihydroartemisinin alleviates doxorubicin-induced cardiotoxicity and ferroptosis by activating Nrf2 and regulating autophagy.

Although the use of Doxorubicin (Dox) is extensive in the treatment of malignant tumor, the toxic effects of Dox on the heart can cause myocardial injury. Therefore, it is necessary to find an alternative drug to alleviate the Dox-induced cardiotoxicity. Dihydroartemisinin (DHA) is a semisynthetic derivative of artemisinin, which is an active ingredient of Artemisia annua. The study investigates the effects of DHA on doxorubicin-induced cardiotoxicity and ferroptosis, which are related to the activation of Nrf2 and the regulation of autophagy. Different concentrations of DHA were administered by gavage for 4 weeks in mice. H9c2 cells were pretreated with different concentrations of DHA for 24 h in vitro. The mechanism of DHA treatment was explored through echocardiography, biochemical analysis, real-time quantitative PCR, western blotting analysis, ROS/DHE staining, immunohistochemistry, and immunofluorescence. In vivo, DHA markedly relieved Dox-induced cardiac dysfunction, attenuated oxidative stress, alleviated cardiomyocyte ferroptosis, activated Nrf2, promoted autophagy, and improved the function of lysosomes. In vitro, DHA attenuated oxidative stress and cardiomyocyte ferroptosis, activated Nrf2, promoted clearance of autophagosomes, and reduced lysosomal destruction. The changes of ferroptosis and Nrf2 depend on selective degradation of keap1 and recovery of lysosome. We found for the first time that DHA could protect the heart from the toxic effects of Dox-induced cardiotoxicity. In addition, DHA significantly alleviates Dox-induced ferroptosis through the clearance of autophagosomes, including the selective degradation of keap1 and the recovery of lysosomes.

Electrocardiographic, biochemical, and scintigraphic evidence for the cardioprotective effect of paricalcitol and vitamin D3 on doxorubicin-induced acute cardiotoxicity in rats.

AIM: We aimed to investigate the possible cardioprotective effects of paricalcitol (PR), its vitamin D receptor agonist, and vitamin D3 (VIT-D3) on an experimental model of doxorubicin (DX) cardiotoxicity by 99mTc-PYP scintigraphy, electrocardiographic (ECG) and biochemical methods. METHOD: Forty-two male Wistar/Albino rats (250‒300 g; aged 10‒12 weeks) were randomly separated into six groups, namely into control (CN), doxorubicin (DX), paricalcitol (PR), vitamin D3 (VIT-D3), paricalcitol + doxorubicin (PR+DX), and vitamin D3 + doxorubicin (VIT-D3+DX) groups. Cardiotoxicity was induced by three doses of DX (18 mg/kg, i.p.) at 24-hour intervals on days 18, 19 and 20. PR (0.5 ug/ kg, i.p) and VIT-D3 (5,000 IU/kg, i.p) were injected for 20 days before and after the application of DX (18 mg/kg, i.p.). On day 21 of the experiment, biochemical parameters [tumor necrosis factor TNF-alpha (TNF-α); interleukin-6 (IL-6), nitric oxide (NO), and cardiac troponin T (cTnT)], as well as ECG and scintigraphic (99mTc-PYP) features were assessed. RESULTS: Compared to CN, DX significantly raised TNF-α, IL-6, and NO in heart tissue, cTnT in serum, 99mTc-PYP uptake in the myocardium, and ECG parameters, specifically QRS complex duration, QT interval duration, and ST-segment amplitude, while also reducing heart rate (p<0.001). Pretreatment with PR and VIT-D3 mitigated these abnormalities produced by DX in the heart (p<0.001). CONCLUSION: Results show that vitamin D receptor agonist paricalcitol and vitamin D protect against DX-induced cardiotoxicity through anti-inflammatory and antioxidant effects (Fig. 4, Ref. 59). Text in PDF www.elis.sk Keywords: paricalcitol, doxorubicin, vitamin D, ECG, 99mTc-PYP scintigraphy, cardiotoxicity, inflammation.

AP39, a novel mitochondria-targeted hydrogen sulfide donor ameliorates doxorubicin-induced cardiotoxicity by regulating the AMPK/UCP2 pathway.

Doxorubicin (DOX) is a broad-spectrum, highly effective antitumor agent; however, its cardiotoxicity has greatly limited its use. Hydrogen sulfide (H2S) is an endogenous gaseous transmitter that exerts cardioprotective effects via the regulation of oxidative stress and apoptosis and maintenance of mitochondrial function, among other mechanisms. AP39 is a novel mitochondria-targeted H2S donor that, at appropriate concentrations, attenuates intracellular oxidative stress damage, maintains mitochondrial function, and ameliorates cardiomyocyte injury. In this study, DOX-induced cardiotoxicity models were established using H9c2 cells and Sprague-Dawley rats to evaluate the protective effect of AP39 and its mechanisms of action. Both in vivo and in vitro experiments showed that DOX induces oxidative stress injury, apoptosis, and mitochondrial damage in cardiomyocytes and decreases the expression of p-AMPK/AMPK and UCP2. All DOX-induced changes were attenuated by AP39 treatment. Furthermore, the protective effect of AP39 was significantly attenuated by the inhibition of AMPK and UCP2. The results suggest that AP39 ameliorates DOX-induced cardiotoxicity by regulating the expression of AMPK/UCP2.

Protective effects of esculetin against doxorubicin-induced toxicity correlated with oxidative stress in rat liver: In vivo and in silico studies.

Doxorubicin (DOX) is widely used in cancer treatment but the dose-related toxicity of DOX on organs including the liver limit its use. Therefore, there is great interest in combining DOX with natural compounds with antioxidant properties to reduce toxicity and increase drug efficacy. Esculetin is a natural coumarin derivative with biological properties encompassing anti-inflammatory and antioxidant activities. In light of these properties, this study was meticulously crafted to investigate the potential of esculetin in preventing doxorubicin (DOX)-induced hepatotoxicity in Sprague-Dawley rats. The rats were divided into a total of six groups: control group, DOX group (administered DOX at a cumulative dose of 5 mg/kg intraperitoneally every other day for 2 weeks), E50 group (administered 50 mg/kg of esculetin intraperitoneally every day), E100 group (administered 100 mg/kg of esculetin intraperitoneally every day) and combined groups (DOX + E50 and DOX + E100) in which esculetin was administered together with DOX. The treatments, both with DOX alone and in combination with E50, manifested a reduction in catalase (CAT mRNA) levels in comparison to the control group. Notably, the enzymatic activities of superoxide dismutase (SOD), CAT, and glutathione peroxidase (GPx) witnessed significant decreases in the liver of rats treated with DOX. Moreover, DOX treatment induced a statistically significant elevation in malondialdehyde (MDA) levels, coupled with a concurrent decrease in glutathione (GSH) levels. Additionally, molecular docking studies were conducted. However, further studies are needed to confirm the hepatoprotective properties of esculetin and to precisely elucidate its mechanisms of action.

Ginsenoside Rb1 attenuates doxorubicin induced cardiotoxicity by suppressing autophagy and ferroptosis.

Ginsenoside Rb1 (Rb1), an active component isolated from traditional Chinese medicine Ginseng, is beneficial to many cardiovascular diseases. However, whether it can protect against doxorubicin induced cardiotoxicity (DIC) is not clear yet. In this study, we aimed to investigate the role of Rb1 in DIC. Mice were injected with a single dose of doxorubicin (20 mg/kg) to induce acute cardiotoxicity. Rb1 was given daily gavage to mice for 7 days. Changes in cardiac function, myocardium histopathology, oxidative stress, cardiomyocyte mitochondrion morphology were studied to evaluate Rb1's function on DIC. Meanwhile, RNA-seq analysis was performed to explore the potential underline molecular mechanism involved in Rb1's function on DIC. We found that Rb1 treatment can improve survival rate and body weight in Dox treated mice group. Rb1 can attenuate Dox induced cardiac dysfunction and myocardium hypertrophy and interstitial fibrosis. The oxidative stress increase and cardiomyocyte mitochondrion injury were improved by Rb1 treatment. Mechanism study found that Rb1's beneficial role in DIC is through suppressing of autophagy and ferroptosis. This study shown that Ginsenoside Rb1 can protect against DIC by regulating autophagy and ferroptosis.

Doxorubicin induces phosphorylation of lamin A/C and loss of nuclear membrane integrity: A novel mechanism of cardiotoxicity.

Lamin A/C, essential inner nuclear membrane proteins, have been linked to progeria, a disease of accelerated aging, and many other diseases, which include cardiac disorder. Lamin A/C mutation and its phosphorylation are associated with altering nuclear shape and size. The role of lamin A/C in regulating normal cardiac function was reported earlier. In the present study, we hypothesized that Doxorubicin (Dox) may alter total lamin A/C expression and phosphorylation, thereby taking part in cardiac injury. An in vitro cellular injury model was generated with Dox (0.1-10.0 µM) treatment on cardiomyoblast cells (H9c2) to prove our hypothesis. Increased size and irregular (ameboid) nucleus shape were observed in H9c2 cells after Dox treatment. Similarly, we have observed a significant increase in cell death on increasing the Dox concentration. The expression of lamin A/C and its phosphorylation at serine 22 significantly decreased and increased, respectively in H9c2 cells and rat hearts after Dox exposure. Phosphorylation led to depolymerization of the lamin A/C in the inner nuclear membrane and was evidenced by their presence throughout the nucleoplasm as observed by immunocytochemistry techniques. Thinning and perforation on the walls of the nuclear membrane were observed in Dox-treated H9c2 cells. LMNA-overexpression in H9c2 protected the cells from Dox-induced cell death, reversing all changes described above. Further, improvement of lamin A/C levels was observed in Dox-treated H9c2 cells when treated with Purvalanol A, a CDK1 inhibitor and N-acetylcysteine, an antioxidant. The study provides new insight regarding Dox-induced cardiac injury with the involvement of lamin A/C and alteration of inner nuclear membrane structure.

Cardiomyocytes, cardiac endothelial cells and fibroblasts contribute to anthracycline-induced cardiac injury through RAS-homologous small GTPases RAC1 and CDC42.

The clinical use of the DNA damaging anticancer drug doxorubicin (DOX) is limited by irreversible cardiotoxicity, which depends on the cumulative dose. The RAS-homologous (RHO) small GTPase RAC1 contributes to DOX-induced DNA damage formation and cardiotoxicity. However, the pathophysiological relevance of other RHO GTPases than RAC1 and different cardiac cell types (i.e., cardiomyocytes, non-cardiomyocytes) for DOX-triggered cardiac damage is unclear. Employing diverse in vitro and in vivo models, we comparatively investigated the level of DOX-induced DNA damage in cardiomyocytes versus non-cardiomyocytes (endothelial cells and fibroblasts), in the presence or absence of selected RHO GTPase inhibitors. Non-cardiomyocytes exhibited the highest number of DOX-induced DNA double-strand breaks (DSB), which were efficiently repaired in vitro. By contrast, rather low levels of DSB were formed in cardiomyocytes, which however remained largely unrepaired. Moreover, DOX-induced apoptosis was detected only in non-cardiomyocytes but not in cardiomyocytes. Pharmacological inhibitors of RAC1 and CDC42 most efficiently attenuated DOX-induced DNA damage in all cell types examined in vitro. Consistently, immunohistochemical analyses revealed that the RAC1 inhibitor NSC23766 and the pan-RHO GTPase inhibitor lovastatin reduced the level of DOX-induced residual DNA damage in both cardiomyocytes and non-cardiomyocytes in vivo. Overall, we conclude that endothelial cells, fibroblasts and cardiomyocytes contribute to the pathophysiology of DOX-induced cardiotoxicity, with RAC1- and CDC42-regulated signaling pathways being especially relevant for DOX-stimulated DSB formation and DNA damage response (DDR) activation. Hence, we suggest dual targeting of RAC1/CDC42-dependent mechanisms in multiple cardiac cell types to mitigate DNA damage-dependent cardiac injury evoked by DOX-based anticancer therapy.

Exploring the effective components of honey-processed licorice (Glycyrrhiza uralensis Fisch.) in attenuating Doxorubicin-induced myocardial cytotoxicity by combining network pharmacology and in vitro experiments.

ETHNOPHARMACOLOGICAL RELEVANCE: Licorice is widely used clinically as one of the most famous traditional Chinese herbs. Its herb roasted with honey is called honey-processed licorice (HPL). Modern studies have shown that HPL has a stronger cardioprotective ability compared to raw licorice (RL), however the material basis and mechanism of action of the potential cardioprotection have not been fully elucidated. AIM OF THE STUDY: To screen and validate the material basis of cardioprotection exerted by HPL and to preliminarily predict the potential mechanism of action. MATERIALS AND METHODS: UPLC-QTOF-MS/MS was used to analyze HPL samples with different processing levels, and differential compounds were screened out through principal component analysis. Network pharmacology and molecular docking were applied to explore the association between differential compounds and doxorubicin cardiomyopathy and their mechanisms of action were predicted. An in vitro model was established to verify the cardioprotective effects of differential compounds. RESULTS: Six differential compounds were screened as key components of HPL for potential cardioprotection. Based on network pharmacology, 113 potential important targets for the treatment of Dox-induced cardiotoxicity were screened. KEGG enrichment analysis predicted that the PI3K-Akt pathway was closely related to the mechanism of action of active ingredients. Molecular docking results showed that the six differential compounds all had good binding activity with Nrf2 protein. In addition, in vitro experiments had shown that five of the active ingredients (liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin, and licochalcone A) can significantly increase Dox-induced H9c2 cell viability, SOD activity, and mitochondrial membrane potential, significantly reduces MDA levels and inhibits ROS generation. CONCLUSION: Liquiritin, isoliquiritin, liquiritigenin, isoliquiritigenin and licochalcone A are key components of HPL with potential cardioprotective capabilities. Five active ingredients can alleviate Dox-induced cardiotoxicity by inhibiting oxidative stress and mitochondrial damage.

Research progress on the role and mechanism of Sirtuin family in doxorubicin cardiotoxicity.

BACKGROUND: Doxorubicin (DOX) is a widely utilized anthracycline chemotherapy drug in cancer treatment, yet its efficacy is hindered by both short-term and long-term cardiotoxicity. Although oxidative stress, inflammation and mitochondrial dysfunction are established factors in DOX-induced cardiotoxicity, the precise molecular pathways remain elusive. Further exploration of the pathogenesis and identification of novel molecular targets are imperative. Recent studies have implicated the Sirtuins family in various physiological and pathological processes, suggesting their potential in ameliorating DOX-induced cardiotoxicity. Moreover, research on Sirtuins has discovered small-molecule compounds or medicinal plants with regulatory effects, representing a notable advancement in preventing and treating DOX-induced cardiac injury. PURPOSE: In this review, we delve into the pathogenesis of DOX-induced cardiotoxicity and explore the therapeutic effects of Sirtuins in mitigating this condition, along with the associated molecular mechanisms. Furthermore, we delineate the roles and mechanisms of small-molecule regulators of Sirtuins in the prevention and treatment of DOX-induced cardiotoxicity. STUDY-DESIGN/METHODS: Data for this review were sourced from various scientific databases (such as Web of Science, PubMed and Science Direct) up to March 2024. Search terms included "Sirtuins," "DOX-induced cardiotoxicity," "DOX," "Sirtuins regulators," "histone deacetylation," among others, as well as several combinations thereof. RESULTS: Members of the Sirtuins family regulate both the onset and progression of DOX-induced cardiotoxicity through anti-inflammatory, antioxidative stress and anti-apoptotic mechanisms, as well as by maintaining mitochondrial stability. Moreover, natural plant-derived active compounds such as Resveratrol (RES), curcumin, berberine, along with synthetic small-molecule compounds like EX527, modulate the expression and activity of Sirtuins. CONCLUSION: The therapeutic role of the Sirtuins family in mitigating DOX-induced cardiotoxicity represents a potential molecular target. However, further research is urgently needed to elucidate the relevant molecular mechanisms and to assess the safety and biological activity of Sirtuins regulators. This review offers an in-depth understanding of the therapeutic role of the Sirtuins family in mitigating DOX-induced cardiotoxicity, providing a preliminary basis for the clinical application of Sirtuins regulators in this condition.

Lapatinib combined with doxorubicin causes dose-dependent cardiotoxicity partially through activating the p38MAPK signaling pathway in zebrafish embryos.

Because of its enhanced antitumor efficacy, lapatinib (LAP) is commonly used clinically in combination with the anthracycline drug doxorubicin (DOX) to treat metastatic breast cancer. While it is well recognized that this combination chemotherapy can lead to an increased risk of cardiotoxicity in adult women, its potential cardiotoxicity in the fetus during pregnancy remains understudied. Here, we aimed to examine the combination of LAP chemotherapy and DOX-induced cardiotoxicity in the fetus using a zebrafish embryonic system and investigate the underlying pathologic mechanisms. First, we examined the dose-dependent cardiotoxicity of combined LAP and DOX exposure in zebrafish embryos, which mostly manifested as pericardial edema, bradycardia, cardiac function decline and reduced survival. Second, we revealed that a significant increase in oxidative stress concurrent with activated MAPK signaling, as indicated by increased protein expression of phosphorylated p38 and Jnk, was a notable pathophysiological event after combined LAP and DOX exposure. Third, we showed that inhibiting MAPK signaling by pharmacological treatment with the p38MAPK inhibitor SB203580 or genetic ablation of the map2k6 gene could significantly alleviate combined LAP and DOX exposure-induced cardiotoxicity. Thus, we provided both pharmacologic and genetic evidence to suggest that inhibiting MAPK signaling could exert cardioprotective effects. These findings have implications for understanding the potential cardiotoxicity induced by LAP and DOX combinational chemotherapy in the fetus during pregnancy, which could be leveraged for the development of new therapeutic strategies.

Mechanistic study of Huangqi Guizhi Wuwu decoction amelioration of doxorubicin-induced cardiotoxicity by reducing oxidative stress and inhibiting cellular pyroptosis.

Huangqi Guizhi Wuwu Decoction (HQGZWWD) has shown promising potential in treating various cardiovascular diseases. This study aimed to elucidate the molecular basis and therapeutic role of HQGZWWD in the treatment of doxorubicin (DOX)-induced myocardial injury. The HPLC fingerprint of HQGZWWD was used to analyze the active components. A DOX-induced myocardial damage rat model was developed, and the therapeutic effects of HQGZWWD were evaluated using echocardiography, myocardial enzyme levels, and hematoxylin and eosin staining. Network pharmacology was used to screen treatment targets, and western blotting and immunohistochemistry were performed to assess cellular pyroptosis levels. Oxidative stress levels were measured using assay kits, and mitochondrial damage was examined using transmission electron microscopy. An in vitro model of DOX-induced cell damage was established, and treatment was administered using serum containing HQGZWWD and N-acetylcysteine (NAC). Oxidative stress levels were detected using assay kits and DCFH-DA, whereas cellular pyroptosis levels were assessed through WB, immunofluorescence, and ELISA assays. HQGZWWD ameliorated DOX-induced myocardial injury. Network pharmacology identified IL-1ß and IL-18 as crucial targets. HQGZWWD downregulated the protein levels of the inflammatory factors IL-1ß and IL-18, inhibited the expression of GSDMD-NT, and simultaneously suppressed the synthesis of Caspase-1, ASC, NLRP3, and Caspase-11. Additionally, HQGZWWD inhibited oxidative stress, and the use of NAC as an oxidative stress inhibitor resulted in significant inhibition of the GSDMD-NT protein in H9C2 cells. These findings highlight the myocardial protective effects of HQGZWWD by inhibiting oxidative stress and suppressing both canonical and non-canonical pyroptotic pathways.

Role of the ß2-adrenergic receptor in podocyte injury and recovery.

BACKGROUND: Podocytes have a remarkable ability to recover from injury; however, little is known about the recovery mechanisms involved in this process. We recently showed that formoterol, a long-acting ß2-adrenergic receptor (ß2-AR) agonist, induced mitochondrial biogenesis (MB) in podocytes and led to renoprotection in mice. However, it is not clear whether this effect was mediated by formoterol acting through the ß2-AR or if it occurred through "off-target" effects. METHODS: We genetically deleted the ß2-AR specifically in murine podocytes and used these mice to determine whether formoterol acting through the podocyte ß2-AR alone is sufficient for recovery of renal filtration function following injury. The podocyte-specific ß2-AR knockout mice (ß2-ARfl/fl/PodCre) were generated by crossing ß2-AR floxed mice with podocin Cre (B6.Cg-Tg(NPHS2-cre)295Lbh/J) mice. These mice were then subjected to both acute and chronic glomerular injury using nephrotoxic serum (NTS) and adriamycin (ADR), respectively. The extent of injury was evaluated by measuring albuminuria and histological and immunostaining analysis of the murine kidney sections. RESULTS: A similar level of injury was observed in ß2-AR knockout and control mice; however, the ß2-ARfl/fl/PodCre mice failed to recover in response to formoterol. Functional evaluation of the ß2-ARfl/fl/PodCre mice following injury plus formoterol showed similar albuminuria and glomerular injury to control mice that were not treated with formoterol. CONCLUSIONS: These results indicate that the podocyte ß2-AR is a critical component of the recovery mechanism and may serve as a novel therapeutic target for treating podocytopathies.

Apigetrin ameliorates doxorubicin prompted testicular damage: biochemical, spermatological and histological based study.

Doxorubicin (DOX) is a highly effective, commonly prescribed, potent anti-neoplastic drug that damages the testicular tissues and leads to infertility. Apigetrin (APG) is an important flavonoid that shows diverse biological activities. The present research was designed to evaluate the alleviative role of APG against DOX-induced testicular damages in rats. Forty-eight adult male albino rats were randomly distributed into 4 groups, control, DOX administered (3 mgkg-1), DOX + APG co-administered (3 mgkg-1 of DOX; 15 mgkg-1 of APG), and APG administered group (15 mgkg-1). Results of the current study indicated that DOX treatment significantly reduced the activities of superoxide dismutase (SOD), glutathione reductase (GSR), catalase (CAT) and glutathione peroxidase (GPx), while increasing the levels of malondialdehyde (MDA) and reactive oxygen species (ROS). DOX treatment also reduced the sperm count, viability, and motility. Moreover, DOX significantly increased the sperm morphological anomalies and reduced the levels of plasma testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The administration of DOX significantly increased the expressions of Bax and Caspase-3, as well as the levels of inflammatory markers. Additionally, DOX treatment significantly downregulated the expressions of steroidogenic enzymes (StAR, 3ß-HSD and 17ß-HSD) and Bcl-2. Furthermore, DOX administration provoked significant histopathological abnormalities in the testicular tissues. However, APG supplementation significantly reversed all the testicular damages due to its androgenic, anti-apoptotic, anti-oxidant and anti-inflammatory nature. Therefore, it is concluded that APG may prove a promising therapeutic agent to treat DOX-induced testicular damages.

The Bach1/HO-1 pathway regulates oxidative stress and contributes to ferroptosis in doxorubicin-induced cardiomyopathy in H9c2 cells and mice.

Doxorubicin (DOX) is one of the most frequently used chemotherapeutic drugs belonging to the class of anthracyclines. However, the cardiotoxic effects of anthracyclines limit their clinical use. Recent studies have suggested that ferroptosis is the main underlying pathogenetic mechanism of DOX-induced cardiomyopathy (DIC). BTB-and-CNC homology 1 (Bach1) acts as a key role in the regulation of ferroptosis. However, the mechanistic role of Bach1 in DIC remains unclear. Therefore, this study aimed to investigate the underlying mechanistic role of Bach1 in DOX-induced cardiotoxicity using the DIC mice in vivo (DOX at cumulative dose of 20 mg/kg) and the DOX-treated H9c2 cardiomyocytes in vitro (1 µM). Our results show a marked upregulation in the expression of Bach1 in the cardiac tissues of the DOX-treated mice and the DOX-treated cardiomyocytes. However, Bach1-/- mice exhibited reduced lipid peroxidation and less severe cardiomyopathy after DOX treatment. Bach1 knockdown protected against DOX-induced ferroptosis in both in vivo and in vitro models. Ferrostatin-1 (Fer-1), a potent inhibitor of ferroptosis, significantly alleviated DOX-induced cardiac damage. However, the cardioprotective effects of Bach1 knockdown were reversed by pre-treatment with Zinc Protoporphyrin (ZnPP), a selective inhibitor of heme oxygenase-1(HO-1). Taken together, these findings demonstrated that Bach1 promoted oxidative stress and ferroptosis through suppressing the expression of HO-1. Therefore, Bach1 may present as a promising new therapeutic target for the prevention and early intervention of DOX-induced cardiotoxicity.

NSUN2 relies on ALYREF to regulate Nrf2-mediated oxidative stress and alleviate Dox-induced liver injury.

BACKGROUND: Doxorubicin (Dox) is associated with various liver injuries, limiting its clinical utility. This study investigates whether NSUN2 participates in Dox-induced liver injury and the associated molecular mechanism. METHODS: In vivo and in vitro liver cell injury models were constructed based on Dox therapy. The protein levels of NSUN2 and oxidative stress indicators Nrf2, HO-1, and NQO1 were evaluated by Western blot. The RNA binding potential was detected by RNA methylation immunoprecipitation (RIP). Additionally, the effect of NSUN2 on Nrf2 mRNA synthesis and localization was evaluated using an RNA fluorescence probe. RESULTS: NSUN2 was downregulated, and liver tissue suffered significant pathological damage in the Dox group. The levels of ALT and AST significantly increased. NSUN2 interference exacerbated Dox-induced liver cell damage, which was reversed by NSUN2 overexpression. RIP demonstrated that NSUN2 recognized and bound to Nrf2 mRNA. Western blot analysis showed the protein level of Nrf2 in the NSUN2-WT group was significantly higher than that of the control group, whereas there was no significant change in Nrf2 level in the mutant NSUN2 group. Luciferase analysis demonstrated that NSUN2 could recognize and activate the Nrf2 5'UTR region of LO2 cells. In addition, RIP analysis revealed that ALYREF could recognize and bind to Nrf2 mRNA and that ALYREF controls the regulatory effect of NSUN2 on Nrf2. CONCLUSION: NSUN2 regulates Dox-induced liver cell damage by increasing Nrf2 mRNA m5C methylation to inhibit inhibiting antioxidant stress. The regulatory effect of NSUN2 on Nrf2 depends on ALYREF.

Hydrangea paniculata coumarins alleviate adriamycin-induced renal lipotoxicity through activating AMPK and inhibiting C/EBPß.

ETHNOPHARMACOLOGICAL RELEVANCE: Throughout Chinese history, Hydrangea paniculata Siebold has been utilized as a traditional medicinal herb to treat a variety of ailments associated to inflammation. In a number of immune-mediated kidney disorders, total coumarins extracted from Hydrangea paniculata (HP) have demonstrated a renal protective effect. AIM OF THE STUDY: To investigate renal beneficial effect of HP on experimental Adriamycin nephropathy (AN), and further clarify whether reversing lipid metabolism abnormalities by HP contributes to its renoprotective effect and find out the underlying critical pathways. MATERIALS AND METHODS: After establishment of rat AN model, HP was orally administrated for 6 weeks. Biochemical indicators related to kidney injury were determined. mRNAs sequencing using kidney tissues were performed to clarify the underlying mechanism. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis, western blot, molecular docking, and drug affinity responsive target stability (DARTS) assay was carried out to further explore and confirm pivotal molecular pathways and possible target by which HP and 7-hydroxylcoumarin (7-HC) played their renal protection effect via modulating lipid metabolism. RESULTS: HP could significantly improve renal function, and restore renal tubular abnormal lipid metabolism and interstitial fibrosis in AN. In vitro study demonstrated that HP and its main metabolite 7-HC could reduce ADR-induced intracellular lipid deposition and fibrosis characteristics in renal tubular cells. Mechanically, HP and 7-HC can activate AMP-activated protein kinase (AMPK) via direct interaction, which contributes to its lipid metabolism modulation effect. Moreover, HP and 7-HC can inhibit fibrosis by inhibiting CCAAT/enhancer binding protein beta (C/EBPß) expression in renal tubular cells. Normalization of lipid metabolism by HP and 7-HC further provided protection of mitochondrial structure integrity and inhibited the nuclear factor kappa-B (NF-κB) pathway. Long-term toxicity using beagle dogs proved the safety of HP after one-month administration. CONCLUSION: Coumarin derivates from HP alleviate adriamycin-induced lipotoxicity and fibrosis in kidney through activating AMPK and inhibiting C/EBPß.