Modulatory effects of miRNAs in doxorubicin resistance: A mechanistic view.

MicroRNAs (miRNAs) are a group of small non-coding RNAs and play an important role in controlling vital biological processes, including cell cycle control, apoptosis, metabolism, and development and differentiation, which lead to various diseases such as neurological, metabolic disorders, and cancer. Chemotherapy consider as gold treatment approaches for cancer patients. However, chemotherapeutic is one of the main challenges in cancer management. Doxorubicin (DOX) is an anti-cancer drug that interferes with the growth and spread of cancer cells. DOX is used to treat various types of cancer, including breast, nervous tissue, bladder, stomach, ovary, thyroid, lung, bone, muscle, joint and soft tissue cancers. Also recently, miRNAs have been identified as master regulators of specific genes responsible for the mechanisms that initiate chemical resistance. miRNAs have a regulatory effect on chemotherapy resistance through the regulation of apoptosis process. Also, the effect of miRNAs p53 gene as a key tumor suppressor was confirmed via studies. miRNAs can affect main biological pathways include PI3K pathway. This review aimed to present the current understanding of the mechanisms and effects of miRNAs on apoptosis, p53 and PTEN/PI3K/Akt signaling pathway related to DOX resistance.

"The protective effect of nano curcumin supplementation on doxorubicin induced cardiotoxicity in breast cancer patients; a randomized, double-blind clinical trial".

BACKGROUND: Anthracycline drugs play a fundamental role in breast cancer treatment; however, the cardiotoxicity side effects obscure the advantages of treatment. Curcumin has antioxidant and anti-inflammatory effects. MATERIALS AND METHODS: In this study, we investigated the effect of nanocurcumin supplementation on Doxorubicin induced Cardiotoxicity. In this randomized clinical trial, a week before starting the doxorubicin regimen for breast cancer patients, the control group received placebo and curcumin group received 80 mg daily dosage of nano curcumin capsules for six months. Echocardiography parameter changes before chemotherapy and after six months were evaluated. RESULTS: 46 patients were included. Left ventricle (LV) ejection fraction significantly decreased and LV end diastolic volume significantly increased in control group but no significant changes were observed in the curcumin group (LVEF: 2.62 ± 59.35 to 4.23 ± 56.85, p-value: 0.014 vs 59.55 ± 1.91 to 58.46 ± 3.41, p-value:0.135; LVEDV: 77.09 ± 15.33 to 80.65 ± 14.54, p-value:0.023 vs 72.41 ± 15.34 74.00 ± 14.25, p-value: 0.294). Additionally, LVEF, LV end systolic diameter (LVESD), and end diastolic diameter (LVEDD) insignificantly more decreased in control group versus curcumin group (LVEF: 4.13 ± 2.50- vs 3.36 ± 1.08-, p-value: 0.223; LVESD: 0.27 ± 0.06-vs 0.120.45 ±, p-value:0.110; LVEDD: -0.44 ± 0.33 vs 0.070.33 ±, p-value:0.269). Furthermore, symptomatic cardiomyopathy and ejection fraction ratio less than 53% were not observed. The LVEF reduction >15% was observed was also high in the control group, (p-value = 0.020). CONCLUSION: This study shows the possible effect of nanocurcumin capsules to reduce the cardiotoxicity of anthracycline chemotherapy medications.

LC-MS/MS method for simultaneous Doxorubicin and Baicalein estimation: formulation and pharmacokinetic applications.

Aim & objective: Combinatorial delivery of Doxorubicin (DOX) and Baicalein (BAC) has a potential to improve breast cancer treatment by mitigating the cardiotoxicity induced by DOX. The nanoformulation has been optimized and subjected to pharmacokinetic studies using LC-MS/MS.Materials & methods: Nanoformulation bearing DOX and BAC was optimized using quality by design approach and method validation was done following USFDA guidelines.Results: The particle size, PDI and zeta potential of developed nanoformulation were 162.56 ± 2.21 nm, 0.102 ± 0.03 and -16.5 ± 1.21 mV, respectively. DOX-BAC-SNEDDs had a higher AUC0-t values of 6128.84 ± 68.71 and 5896.62 ± 99.31 ng/mL/h as compared with DOX-BAC suspension.Conclusion: These findings hold promise for advancing breast cancer treatment and facilitating therapeutic drug monitoring.

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Galangin alleviated Doxorubicin-induced cardiotoxicity by inhibiting ferroptosis through GSTP1/JNK pathway.

BACKGROUND: Doxorubicin (DOX) is a potent anticancer medication, but its significant cardiotoxicity poses a challenge in clinical practice. Galangin (Gal), a flavonoid compound with diverse pharmacological activities, has shown potential in exerting cardioprotective effects. However, the related molecular mechanism has not been fully elucidated. PURPOSE: Combined with bioinformatics and experimental verification methods to investigate Gal's potential role and underlying mechanisms in mitigating DOX-induced cardiotoxicity (DIC). METHODS: C57BL/6 mice received a single dose of DOX via intraperitoneal injection 4 days before the end of the gavage period with Gal. Myocardial injury was evaluated using echocardiography, myocardial injury biomarkers, Sirius Red and H&E staining. H9c2 cells were stimulated with DOX to mimic DIC in vitro. The potential therapeutic target of Gal was identified through network pharmacology, molecular docking and cellular thermal shift assay (CETSA), complemented by an in-depth exploration of the GSTP1/JNK signaling pathway using immunofluorescence. Subsequently, the GSTP1 inhibitor Ezatiostat (Eza) substantiated the signaling pathway. RESULTS: Gal administration considerably raised DOX-inhibited the left ventricular ejection fractions (LVEF), reduced levels of myocardial injury markers (c-TnI, c-TnT, CKMB, LDH, and AST), and alleviated DOX-induced myocardial histopathological injury and fibrosis in mice, thereby improving cardiac dysfunction. The ferroptosis induced by DOX was inhibited by Gal treatment. Gal remarkably ameliorated the DOX-induced lipid peroxidation, accumulation of iron and Ptgs2 expression both in H9c2 cells and cardiac tissue. Furthermore, Gal effectively rescued the DOX-inhibited crucial regulators of ferroptosis such as Gpx4, Nrf2, Fpn, and Slc7a11. The mechanistic investigations revealed that Glutathione S-transferase P1 (GSTP1) may be a potential target for Gal in attenuating DIC. Gal act on GSTP1 by stimulating its expression, thereby enhancing the interaction between GSTP1 and c-Jun N-terminal kinase (JNK), leading to the deactivation of JNK/c-Jun pathway. Furthermore, interference of GSTP1 with inhibitor Eza abrogated the cardioprotective and anti-ferroptotic effects of Gal, as evidenced by decreased cell viability, reduced expression of GSTP1 and Gpx4, elevated MDA levels, and promoted phosphorylation of JNK and c-Jun compared with Gal treatment. CONCLUSION: Gal could inhibit ferroptosis and protect against DIC through regulating the GSTP1/JNK pathway. Our research has identified a novel pathway through which Gal regulates DIC, providing valuable insights into the potential therapeutic efficacy of Gal in mitigating cardiotoxic effects.

Investigation of Dual-Loaded Doxorubicin and Sorafenib Liposomes Co-Modified with Glycyrrhetinic Acid and Cell-Penetrating Peptide TAT.

BACKGROUND: Combining Doxorubicin (DOX) with sorafenib (SF) is a promising strategy for treating Hepatocellular Carcinoma (HCC). However, strict dosage control is required for both drugs, and there is a lack of target selectivity. OBJECTIVE: This study aims to develop a novel nano-drug delivery system for the combined use of DOX and SF, aiming to reduce their respective dosages, enhance therapeutic efficacy, and improve target selectivity. METHODS: DOX/SF co-loaded liposomes (LPs) were prepared using the thin-film hydration method. The liposomes were modified with 1,2-distearoyl-sn-glycero-3-phospho-ethanolamine (DSPE)- polyethylene glycol (PEG2000), DSPE-PEG1000-cell penetrating peptide TAT, and Glycyrrhetinic Acid (GA). The basic properties of the liposomes were characterized. CCK-8 cell viability assays were conducted using HepG2, MHCC97-H, and PLC cell models, and apoptosis experiments were performed using HepG2 cells to determine if this delivery system could reduce the respective dosages of DOX and SF and enhance HCC cytotoxicity. Liposome uptake experiments were performed using HepG2 cells to validate the target selectivity of this delivery system. RESULTS: A GA/TAT-DOX/SF-LP liposomal nano drug delivery system was successfully constructed, with a particle size of 150 nm, a zeta potential of -7.9 mV, a DOX encapsulation efficiency of 92%, and an SF encapsulation efficiency of 88.7%. Cellular experiments demonstrated that this delivery system reduced the required dosages of DOX and SF, exhibited stronger cytotoxicity against liver cancer cells, and showed better target selectivity. CONCLUSION: A simple and referenceable liposomal nano drug delivery system has been developed for the combined application of DOX and SF in hepatocellular carcinoma treatment.

In vivo cardioprotective effect of zinc oxide nanoparticles against doxorubicin-induced myocardial infarction by enhancing the antioxidant system and nitric oxide production.

BACKGROUND: Myocardial infarction (MI) is the result of reduced or stopped blood supply to a section of the myocardium. Regardless of its potential effectiveness in the treatment of several types of cancers, doxorubicin (DOX) capabilities are restricted because of its widespread cardiotoxic impact. AIM: In this study, the protective effect of zinc oxide nanoparticles against doxorubicin-induced myocardial infarction in rats is examined. METHODS: Zinc oxide nanoparticles (ZnO NPs) were synthesized and characterized using X-ray diffraction, transmission electron microscope, and UV-Vis spectral analysis. A total cumulative dose of DOX (18 mg/kg body weight, i.p.) was injected once daily on days 2, 4, 6, 8, 10, and 12 (i.p.) to induce MI in rats. 24 rats were divided into 4 groups; control, MI, and MI treated with two doses of ZnO NPs (45 and 22.5 mg/kg). RESULTS: The treatment with ZnO NPs restored ST-segment near normal, ameliorated the changes in cardiac troponin T, creatine kinase, lactate dehydrogenase, aspartate aminotransferase, alanine amino transferase, alkaline phosphatase, total proteins, malondialdehyde, nitric oxide, reduced glutathione, and catalase.The histological investigation revealed that ZnO NPs treated group showed marked improvement in the examined cardiac muscle and liver in numerous sections.The lower dose of ZnO NPs (22.5 mg/kg) was significantly more effective than the higher dose (45 mg/kg). CONCLUSION: The effect of ZnO NPs against doxorubicin-induced myocardial infarction in rats was assessed and the results revealed a successful cardioprotective potency through enhancing the antioxidant system and stimulating nitric oxide production in myocardial infarcted rats. This work implies that ZnO NPs could serve as promising agents for treating doxorubicin-induced cardiotoxicity.

Identification of autophagy-related signatures in doxorubicin-induced cardiotoxicity.

PURPOSE: Doxorubicin is an antibiotic drug used clinically to treat infectious diseases and tumors. Unfortunately, it is cardiotoxic. Autophagy is a cellular self-decomposition process that is essential for maintaining homeostasis in the internal environment. Accordingly, the present study was proposed to characterize the autophagy-related signatures of doxorubicin-induced cardiotoxicity. METHODS: Datasets related to doxorubicin-induced cardiotoxicity were retrieved by searching the GEO database and differentially expressed genes (DEGs) were identified. DEGs were taken to intersect with autophagy-related genes to obtain autophagy-related signatures, and Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and protein-protein interaction (PPI) network were performed on them. Further, construction of miRNA-hub gene networks and identification of target drugs to reveal potential molecular mechanisms and therapeutic strategies. Animal models of doxorubicin-induced cardiotoxicity were constructed to validate differences in gene expression for autophagy-related signatures. RESULTS: PBMC and heart samples from the GSE37260 dataset were selected for analysis. There were 995 and 2357 DEGs in PBMC and heart samples, respectively, and they had 23 intersecting genes with autophagy-related genes. RT-qPCR confirmed the differential expression of 23 intersecting genes in doxorubicin-induced cardiotoxicity animal models in general agreement with the bioinformatics results. An autophagy-related signatures consisting of 23 intersecting genes is involved in mediating processes and pathways such as autophagy, oxidative stress, apoptosis, protein ubiquitination and phosphorylation. Moreover, Akt1, Hif1a and Mapk3 are hub genes in autophagy-associated signatures and their upstream miRNAs are mainly rno-miR-1188-5p, rno-miR-150-3p and rno-miR-326-3p, and their drugs are mainly CHEMBL55802, Carboxyamidotriazole and 3-methyladenine. CONCLUSION: This study identifies for the first-time autophagy-related signatures in doxorubicin's cardiotoxicity, which could provide potential molecular mechanisms and therapeutic strategies for doxorubicin-induced cardiotoxicity.

The protective effect of Ghrelin peptide on doxorubicin hydrochloride induced heart failure in rats.

BACKGROUND: To investigate the protective effect and mechanism of Ghrelin on Doxorubicin (Dox) hydrochloride induced heart failure (HF) and myocardial injury in rats. METHODS: 45 rats were randomly divided into control group, HF group and Ghrelin group. Dox hydrochloride was injected intraperitoneally to establish the model of HF in rats of HF group and Ghrelin group. Rats in the Ghrelin group were given intraperitoneal injection of Ghrelin twice a day, and rats in the HF group and control group were given equal volume of normal saline for a total of 6 weeks. The changes of echocardiography, cardiac hemodynamics, myocardial histology and plasma inflammatory factors were observed. RESULTS: After the Ghrelin intervention, compared with the HF group, the left ventricular end-diastolic diameter (LVDD) and left ventricular end-systolic diameter (LVSD) in the Ghrelin group was markedly reduced (P < 0.05), and left ventricular ejection fraction (LVEF) was significantly increased (P < 0.05). Compared with HF group, the left ventricular systolic pressure (LVSP), maximum rate of increase in left ventricular pressure (+ dP/dtmax) and maximum rate of decrease in left ventricular pressure (- dP/dtmax) of Ghrelin group was remarkedly increased (P < 0.05), left ventricular diastolic pressure (LVDP) decreased (P < 0.05). In the Ghrelin group, the degree and extent of cardiomyocyte degeneration and necrosis were remarkedly reduced compared with the HF group. The levels of TNF-α and iNOS in Ghrelin group were notably lower than those in HF group (P < 0.05), the IL-10 level increased markedly (P < 0.05). CONCLUSION: Ghrelin may reduce Dox-induced myocardial injury and improve cardiac function in rats by regulating inflammation and oxidative stress.

Asiatic acid ameliorates doxorubicin-induced cardiotoxicity by promoting FPN-mediated iron export and inhibiting ferroptosis.

Doxorubicin (DOX), a common chemotherapeutic agent in cancer therapy, is accompanied by pronounced cardiotoxicity. Ferroptosis has been implicated in the pathogenesis and therapeutics of DOX-induced cardiotoxicity (DIC). Asiatic acid (AA), a pentacyclic triterpene from the Chinese medicinal herb Centella asiatica, displays antioxidant, anti-inflammatory, and antiapoptotic activities. In this study, we investigated the beneficial effects of AA against DOX-induced ferroptosis and cardiotoxicity and the underlying mechanisms. A chronic DIC model was established by challenging mice with DOX (5 mg/kg, i.p.) once per week for 4 weeks. Concurrent with DOX insult, the mice were administered AA (25 mg·kg-1·d-1, i.g.). Cardiac function and mechanical properties of isolated cardiomyocytes were evaluated at the end of treatment. We showed that AA administration preserved cardiac function, significantly reduced cardiac injury, and improved cardiomyocyte contractile function in DIC mice. The beneficial effects of AA were causally linked to the inhibition of DOX-induced ferroptosis both in vivo and in vitro. We revealed that AA attenuated DOX-induced iron accumulation in HL-1 cells by increasing FPN-mediated iron export, in a Nrf2-dependent manner. AA upregulated Nrf2 expression and promoted Nrf2 nuclear translocation in DOX-treated HL-1 cells. Moreover, AA-offered benefits against DOX-induced cardiac dysfunction and ferroptosis were abolished by Nrf2 inhibitor ML385 (30 mg·kg-1·d-1, i.p.) administrated 30 min before AA in DIC mice. Our data favor that AA promotes FPN-mediated iron export to inhibit iron overload and ferroptosis in DIC, suggesting its therapeutic potential in the treatment of DIC.

On the Development of Polylactic Acid/Polycaprolactone Blended Films with High Retention Capacity.

The retention capacity of polymers is related to the development of systems that combine high surface-to-volume ratio with good handling and specific functionality. Biodegradability and biocompatibility are also key features for extending the field of applications to areas such as biomedicine. With this in mind, the aim of this work is to develop biodegradable, biocompatible, and highly functionalized porous films, that ensure suitable handling and a good surface-to-volume ratio. Polylactic acid (PLA) is applied as a polymer matrix to which a polycaprolactone with a star-shaped architecture (PCL-COOH) to ensure a high concentration of carboxylic end functionalities is added. The porous films are prepared using the phase inversion technique, which, as shown by Scanning Electron Microscopy (SEM) analysis, promotes good dispersion of the PCL-COOH domains. Absorption and release measurements performed with a positively charged model molecule show that the retention capacity and release rate can be tuned by changing the PCL-COOH concentration in the systems. Moreover, the adsorption properties for the formulation with the highest PCL-COOH content are also demonstrated with a real and widely used drug, namely doxorubicin. Finally, the bio- and hemocompatibility of the films, which are enzymatically degradable, are evaluated by using human keratinocytes and red blood cells, respectively.

Pleural Kaposi Sarcoma in Two HIV-Positive Patients.

Kaposi sarcoma is a neoplasm caused by human herpes virus 8 (HHV-8) that commonly presents as subcutaneous lesions but can also involve visceral organs such as the gastrointestinal and pulmonary systems. Diagnosis is achieved through histopathological analysis of cutaneous lesions or lymph nodes. In this study, we report two patients, recently diagnosed with HIV, who were later found to have cutaneous and visceral (pleural) Kaposi sarcoma. In both cases, the patients presented with dyspnea accompanied by cutaneous lesions and bilateral pleural effusion. Unfortunately, the first patient did not survive long enough for treatment initiation. The second patient, however, demonstrated a favorable response to a treatment regimen comprising highly active antiretroviral therapy (HAART) and liposomal doxorubicin.

Penile hemangiosarcoma as a cause of stranguria in a dog: clinical presentation, imaging findings, treatment and outcome.

Background: Penile tumors are rare in dogs and only single case reports or small case series have been reported. Case description: An 11-year-old, cross-breed dog was presented for a two-week history of stranguria. At physical examination, a subcutaneous swelling of the penis was detected. Abdominal radiographs, ultrasonography, and CT showed a subcutaneous penile mass involving the penile urethra and bulbus glandis associated with marked lysis of the os penis. Histological features along with the neoplastic cell positivity to CD31 and FVIII immunohistochemical markers warranted a final diagnosis of penile hemangiosarcoma. Findings/treatment and outcome: The dog was treated with amputation of the penis, scrotal urethrostomy, and five adjuvant doses of doxorubicin along with thalidomide. Cutaneous and omental metastases were found 235 days after surgery. The dog was euthanized at 296 days due to bone and pulmonary metastasis. Conclusion: Penile hemangiosarcoma seems to share the same aggressive behavior with other hemangiosarcomas seen in other anatomical locations. Therefore, surgery and chemotherapy may improve survival time in dogs with penile hemangiosarcoma as well.

Mitigating Cardiotoxicity Associated with Anticancer Drugs: An Updated Systematic Review.

Introduction: This systematic review investigated strategies to mitigate cardiotoxicity induced by anticancer medications, emphasizing exercise and pharmacological interventions. Methods: We systematically reviewed three randomized controlled trials, one ATOPE trial, and one retrospective cohort study. Results: Among 448 patients, exercise interventions, particularly in breast cancer patients, demonstrated significant improvements in left ventricular ejection fraction (LVEF) and cardiotoxicity prevention. Pharmacological interventions, including candesartan and carvedilol, have shown potential in reducing early DOX-induced subclinical cardiotoxicity (DISC). The protective efficacy of candesartan in alleviating DISC was greater than carvedilol and the control group. Combination therapy with lisinopril and bisoprolol effectively preserved the LVEF. A retrospective cohort study demonstrated the cardioprotective potential of sodium-glucose cotransporter-2 inhibitors in reducing cardiovascular events. Conclusion: This systematic review underscores the promise of exercise and pharmacological interventions for preserving cardiac function in cancer patients receiving chemotherapy. These findings have significant implications for enhancing the quality of care for cancer patients.

Determination of doxorubicin in plasma and tissues of mice by UPLC-MS/MS and its application to pharmacokinetic study.

A rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the simultaneous determination of doxorubicin (DOX) in mouse plasma and tissues, including the heart, liver, spleen, lung, kidney and tumor, and to investigate the pharmacokinetics and distribution in mice. In this study, daunorubicin (DNR) was used as an internal standard, and the mobile phase consisted of ammonium formate 2 mM containing 0.1 % formic acid (A) and acetonitrile (B), the chromatographic column was ACQUITY UPLC BEHTM C18 with a gradient elution at a flow rate of 0.2 mL/min. Electrospray ionization (ESI) in positive ion pattern was utilized for the ion separation of DOX, with the ions used for quantitative analysis being DOX m/z 544.28 â†’ 397.10 and DNR m/z 528.35 â†’ 321.08, respectively. The results showed that a good linear relationship in the calibration curve range of 1-800 ng/mL in mouse plasma and 1-2500 ng/g in tissues (R2 > 0.99) with the limits of quantification of 1 ng/mL in plasma and tissues. The method exhibited good matrix effect and extraction recovery, with the intra-day and inter-day precision of plasma and tissue were less than 10.3 % and 15.4 %, and the relative error (RE) were both less than ±14.8 % and ±18.9 %, respectively. The stability results under different conditions were found to be accurate. It also revealed the distribution of DOX in various tissues of mice, with the concentration ranking as liver > heart > kidney > spleen > lung > tumor. This method was successfully used to the study for the pharmacokinetics in plasma and drug distribution in tissues of BALB/c mice.

Piperine enhances doxorubicin sensitivity in triple-negative breast cancer by targeting the PI3K/Akt/mTOR pathway and cancer stem cells.

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that lacks an actionable target with limited treatment options beyond conventional chemotherapy. Therapeutic failure is often encountered due to inherent or acquired resistance to chemotherapy. Previous studies implicated PI3K/Akt/mTOR signaling pathway in cancer stem cells (CSCs) enrichment and hence chemoresistance. The present study aimed at investigating the potential effect of piperine (PIP), an amide alkaloid isolated from Piper nigrum, on enhancing the sensitivity of TNBC cells to doxorubicin (DOX) in vitro on MDA-MB-231 cell line and in vivo in an animal model of Ehrlich ascites carcinoma solid tumor. Results showed a synergistic interaction between DOX and PIP on MDA-MB-231 cells. In addition, the combination elicited enhanced suppression of PI3K/Akt/mTOR signaling that paralleled an upregulation in this pathway's negative regulator, PTEN, along with a curtailment in the levels of the CSCs surrogate marker, aldehyde dehydrogenase-1 (ALDH-1). Meanwhile, in vivo investigations demonstrated the potential of the combination regimen to enhance necrosis while downregulating PTEN and curbing PI3K levels as well as p-Akt, mTOR, and ALDH-1 immunoreactivities. Notably, the combination failed to change cleaved poly-ADP ribose polymerase levels suggesting a pro-necrotic rather than pro-apoptotic mechanism. Overall, these findings suggest a potential role of PIP in decreasing the resistance to DOX in vitro and in vivo, likely by interfering with the PI3K/Akt/mTOR pathway and CSCs.

Changes in the Sensitivity of MCF-7 and MCF-7/DX Breast Cancer Cells to Cytostatic in the Presence of Metformin.

Multidrug resistance is a serious problem in modern medicine and the reason for the failure of various therapies. A particularly important problem is the occurrence of multidrug resistance in cancer therapies which affects many cancer patients. Observations on the effect of metformin-a well-known hypoglycemic drug used in the treatment of type 2 diabetes-on cancer cells indicate the possibility of an interaction of this substance with drugs already used and, as a result, an increase in the sensitivity of cancer cells to cytostatics. The aim of this study was to evaluate the effect of metformin on the occurrence of multidrug resistance of breast cancer cells. The MCF-7-sensitive cell line and the MCF-7/DX cytostatic-resistant cell line were used for this study. WST-1 and LDH assays were used to evaluate the effects of metformin and doxorubicin on cell proliferation and viability. The effect of metformin on increasing the sensitivity of MCF-7 and MCF-7/DX cells to doxorubicin was evaluated in an MDR test. The participation of metformin in increasing the sensitivity of resistant cells to the effect of the cytostatic (doxorubicin) has been demonstrated.

Regulating Drug Release Performance of Acid-Triggered Dimeric Prodrug-Based Drug Self-Delivery System by Altering Its Aggregation Structure.

Dimeric prodrugs have been investigated intensely as carrier-free drug self-delivery systems (DSDSs) in recent decades, and their stimuli-responsive drug release has usually been controlled by the conjugations between the drug molecules, including the stimuli (pH or redox) and responsive sensitivity. Here, an acid-triggered dimeric prodrug of doxorubicin (DOX) was synthesized by conjugating two DOX molecules with an acid-labile ketal linker. It possessed high drug content near the pure drug, while the premature drug leakage in blood circulation was efficiently suppressed. Furthermore, its aggregation structures were controlled by fabricating nanomedicines via different approaches, such as fast precipitation and slow self-assembly, to regulate the drug release performance. Such findings are expected to enable better anti-tumor efficacy with the desired drug release rate, beyond the molecular structure of the dimeric prodrug.

Targeted Polymeric Micelles System, Designed to Carry a Combined Cargo of L-Asparaginase and Doxorubicin, Shows Vast Improvement in Cytotoxic Efficacy.

L-asparaginases (ASP) and Doxorubicin (Dox) are both used in the treatment of leukemia, including in combination. We have attempted to investigate if their combination within the same targeted delivery vehicle can make such therapy more efficacious. We assembled a micellar system, where the inner hydrophobic core was loaded with Dox, while ASP would absorb at the surface due to electrostatic interactions. To make such absorption stronger, we conjugated the ASP with oligoamines, such as spermine, and the lipid components of the micelle-lipoic and oleic acids-with heparin. When loaded with Dox alone, the system yielded about a 10-fold improvement in cytotoxicity, as compared to free Dox. ASP alone showed about a 2.5-fold increase in cytotoxicity, so, assuming additivity of the effect, one could expect a 25-fold improvement when the two agents are applied in combination. But in reality, a combination of ASP + Dox loaded into the delivery system produced a synergy, with a whopping 50× improvement vs. free individual component. Pharmacokinetic studies have shown prolonged circulation of micellar formulations in the bloodstream as well as an increase in the effective concentration of Dox in micellar form and a reduction in Dox accumulation to the liver and heart (which reduces hepatotoxicity and cardiotoxicity). For the same reason, Dox's liposomal formulation has been in use in the treatment of multiple types of cancer, almost replacing the free drug. We believe that an opportunity to deliver a combination of two types of drugs to the same target cell may represent a further step towards improvement in the risk-benefit ratio in cancer treatment.

Losmapimod ameliorates doxorubicin-induced cardiotoxicity through attenuating senescence and inflammatory pathways.

Irreversible cardiotoxicity limits the clinical application of doxorubicin (DOX). DOX-induced cardiotoxicity has been associated with induction of senescence and activation of the p38 MAPK pathway. Losmapimod (LOSM), an orally active p38 MAPK inhibitor, is an anti-inflammatory agent with cardioprotective effects. Nevertheless, the effect of LOSM against DOX-induced cardiotoxicity has not been reported. In this study, we determined the effects of LOSM on DOX-induced chronic cardiotoxicity in C57BL/6 N mice. Five-week-old C57BL/6 N mice were fed diet containing LOSM (estimated daily intake 12 mg/kg/day) or a control diet for four days. Thereafter, mice were randomized to receive six weekly intraperitoneal injections of either DOX (4 mg/kg) or saline. Three days after the last injection, cardiac function was assessed by trans-thoracic echocardiography. Activation of p38, JNK, and ERK1/2 MAPKs were assessed by immunoblotting in the heart and liver. Gene expressions of senescence, inflammatory, oxidative stress, and mitochondrial function markers were quantified using real-time PCR and serum inflammatory markers were assessed by Luminex. Our results demonstrated that LOSM attenuated p38 MAPK activation, ameliorated DOX-induced cardiac dysfunction, and abrogated DOX-induced expression of the senescence marker p21Cip1. Additionally, LOSM demonstrated anti-inflammatory effects, with reduced cardiac Il-1α and Il-6 gene expression in DOX-treated mice. Systemic inflammation, assessed by serum cytokine levels, showed decreased IL-6 and CXCL1 in both DOX-treated mice and mice on LOSM diet. LOSM significantly increased mitofusin2 gene expression, which may enhance mitochondrial fusion. These findings underscore the potential therapeutic efficacy of p38 MAPK inhibition, exemplified by LOSM, in ameliorating DOX-induced cardiotoxicity, senescence, and inflammation.

Preparation of double-loaded bitter ginseng derivative B21-DOX liposomes co-modified with SP94 and BR2 ligand and its in vitro anti-hepatocarcinogenic effect.

AIM: To construct a novel liposomal drug delivery system co-modified with SP94 and BR2 ligands, encapsulating both the bitter ginseng derivative B21 and doxorubicin (DOX), to achieve superior anti-tumour efficacy and reduced toxic side effects. METHODS: Liposomes were prepared using an organic phase reaction method, with B21 encapsulated in the lipid phase and DOX in the aqueous phase. The liposomes were further modified with SP94 and BR2 peptides. The characterisations, cytotoxicity, and in vitro targeting effects were assessed through various methods including ultraviolet spectrophotometry, high-performance liquid chromatography, nano-size analysis, ultrafiltration centrifugation, dialysis, transmission electron microscopy, flow cytometry, Methylthiazolyldiphenyl-tetrazolium bromide assay, confocal laser scanning microscopy, transwell assay, and tumorsphere assay. RESULTS: SP94/BR2-B21/DOX-LP liposomes were spherical with an average diameter of 120.87 ± 1.00 nm, a polydispersity index (PDI) of 0.223 ± 0.006, and a surface charge of -23.1 ± 1.27 mV. The encapsulation efficiencies for B21 and DOX were greater than 85% and 97% (mg/mg), respectively. The results indicated that SP94/BR2-B21/DOX-LP exhibited enhanced targeting and cytotoxicity compared to single-ligand modified and unmodified liposomes, with the combined encapsulation of B21 and DOX showing synergistic anti-hepatocarcinogenic effects. CONCLUSION: SP94/BR2-B21/DOX-LP liposomes represent a promising targeted drug delivery system for hepatocellular carcinoma, offering improved membrane penetration, enhanced therapeutic efficacy, and reduced systemic toxicity.