Phloretin alleviates doxorubicin-induced cardiotoxicity through regulating Hif3a transcription via targeting transcription factor Fos

Esculetin and Phloretin Combination Mitigates Acute Kidney Injury-Diabetes Comorbidity via Regulating Mitophagy and Inflammation: A Dual-Pronged Approach

Induction of PINK1/Parkin-mediated mitophagy and reducing inflammation via targeting the TLR4/NF-κB axis simultaneously could be a promising therapy for the complex pathophysiology of AKI-diabetes comorbidity. Earlier, esculetin by mitophagy activation and phloretin by inhibiting inflammation have shown promising renoprotection. Therefore, we aimed to evaluate the synergistic renoprotective ability of esculetin and phloretin combination against AKI-diabetes comorbidity. AKI-diabetes comorbidity was mimicked in vivo by bilateral ischemia/reperfusion injury (IRI) in diabetic rats and in vitro by sodium azide-induced hypoxia/reperfusion injury (HRI) under hyperglycemic conditions. The cells were pretreated with esculetin (50 μM) and phloretin (50 μM) for 24 h. Similarly, the diabetic AKI rats received esculetin (50 mg/kg/day, p.o.) and phloretin (50 mg/kg/day, p.o.) pretreatment for 4 days and 1 h before surgery. Further, the obtained samples were utilized for different experiments. Esculetin and phloretin in diabetic AKI rats preserved kidney function and prevented kidney injury, indicated by reduced plasma creatinine, blood urea nitrogen, and kidney injury molecule 1. Esculetin improved mitophagy, indicated by increased mitophagosome formation, increased PINK1, Parkin, LC3B, and decreased p62 expression. Similarly, phloretin suppressed the diabetic AKI-related increased expression of inflammatory mediators including NF-κB, TLR4, TNF-α, and MCP-1. Moreover, combination therapy showed a more pronounced effect via synergistically improving mitophagy, maintaining ΔΨm, preventing mitochondrial dysfunction, reducing inflammation, and apoptosis. Esculetin and phloretin combination ameliorated AKI-diabetes comorbidity more effectively than their monotherapies. Esculetin upregulated the PINK1/Parkin-mediated mitophagy, and phloretin reduced inflammation by inhibiting the TLR4/NF-κB axis, thereby synergistically preventing kidney dysfunction.

HPLC-ESI-QTOF-MS profiling of antibacterial bioactive solvent fractions of Senna alata (L.) roxb (Fabaceae) leaves, and in silico prediction of pharmacokinetic, drug-likeness, and toxicity of major phyto-components

ETHNOPHARMACOLOGICAL RELEVANCE

Medicinal plants are a rich source of new antibacterial leads. One such plant is Senna alata (L.) Roxb (Fabaceae), a valuable medicinal tree known in folk medicine for its effectiveness in treating various ailments such as ringworms, wounds, diabetes, skin diseases, hypertension, malaria, mycosis, and bacterial diseases.

AIM OF THE STUDY

This study assesses the antibacterial and antibiotic-resistance reversal properties of S. alata leaf extracts against 32 multi-drug resistant (MDR) clinically relevant bacterial strains and clinical isolates.

MATERIALS AND METHODS

The hydromethanol extract (70%) was obtained through ultrasound-assisted extraction, followed by partitioning with solvents of increasing polarity, specifically petroleum ether (PE), ethyl acetate (EA), n-butanol (n-BuOH), and water, to isolate different fractions. Antibacterial and combination tests were conducted using the broth microdilution method. Subsequently, high-resolution HPLC-ESI-QTOF-MS analysis was performed to profile the bioactive secondary metabolites in the most active fractions. In addition, the pharmacokinetic (PK) properties, drug-likeness, and medicinal chemistry of the key phytoconstituents were predicted in silico using SwissADME. Moreover, we utilized the ProTox-II web server to predict the toxicity profile of the potential drug candidates.

RESULTS

The herbal fractions, except for the water fraction, showed remarkable antibacterial activity, with MICs ranging from 16 to 1024 μg/mL. The ethyl acetate (SA-EA) and n-butanol (SA-n-BuOH) fractions were the most potent, with the overall most significant effects recorded with SA-EA (with MIC <100 μg/mL on 31 out of the 32 MDR studied strains). Additionally, SA-EA enhanced the efficacy of antibiotics, leading to up to a 64-fold reduction in MICs (of chloramphenicol, imipenem, ciprofloxacin, cefepime, and doxycycline) in combination. A total of 27 and 36 compounds were tentatively identified from SA-EA and SA-n-BuOH, respectively, with the majority being phenolic compounds known for their antibacterial properties. Furthermore, 17 phytochemicals were reported for the first time in S. alata fractions. Seven metabolites, including phloretin, 7,4'-dihydroxyflavone, isorhamnetin, apigenin, genistein, naringenin, and lactarorufin B, emerged as potential drug candidates that satisfy most of the drug candidacy criteria and PK profile amongst which apigenin, genistein, and naringenin depicted the best safety profile.

CONCLUSION

The positive outcomes observed in the antibacterial activity assays, coupled with the presence of bioactive metabolites and emerging drug leads in these fractions, underscore the importance of selecting S. alata for the discovery and development of new antibacterial agents targeting MDR phenotypes.

Oridonin Alleviates Doxorubicin-Induced Cardiotoxicity by Inhibiting p38 MAPK/MMP3 Signaling Pathway

Although doxorubicin (DOX) is an efficient chemotherapeutic drug for human tumors, severe cardiotoxicity restricts its clinical use. Oridonin (Ori), a bioactive component isolated from Isodon rubescens (Hemsl.) H. Hara, possesses potent anti-inflammatory and anticancer potentials. Therefore, our study aimed to evaluate the protective effects of Ori against DOX-induced cardiotoxicity. DIC models were established in vivo and in vitro. The action targets and pharmaceutical mechanism of Ori against DIC were comprehensively examined by network pharmacology, RNA-sequencing, and experimental validation. Ori relieved Dox-induced cell apoptosis in vitro and in vivo. A total of 7084 DEGs, 196 Ori, and 8172 DIC targets were screened by transcriptomics and network pharmacology, respectively. The three sets contained 11 intersection genes, including Ccl2, Myc, Mmp3, Egfr, p38 MAPK (MAPK14), Esr1, Tnf, Jun, Cdk1, Alb, and Ccnd1. The experimental results showed that Ori significantly decreased MMP-3 activity and the expression of p38 MAPK, thereby attenuating myocardial apoptosis and inflammatory infiltration. This study suggests that Ori is a potential therapeutic agent for DOX-induced cardiotoxicity that exerts its effects by inhibiting the p38 MAPK/MMP-3 signaling pathway.

Network pharmacology combined with molecular docking and dynamics to assess the synergism of esculetin and phloretin against acute kidney injury-diabetes comorbidity

Acute kidney injury (AKI) is a global health concern with high incidence and mortality, where diabetes further worsens the condition. The available treatment options are not uniformly effective against the complex pathogenesis of AKI-diabetes comorbidity. Hence, combination therapies based on the multicomponent, multitarget approach can tackle more than one pathomechanism and can aid in AKI-diabetes comorbidity management. This study aimed to investigate the therapeutic potential of esculetin and phloretin combination against AKI-diabetes comorbidity by network pharmacology followed by validation by molecular docking and dynamics. The curative targets for diabetes, AKI, esculetin, and phloretin were obtained from DisGeNET, GeneCards, SwissTargetPrediction database. Further, the protein-protein interaction of the potential targets of esculetin and phloretin against AKI-diabetes comorbidity was investigated using the STRING database. Gene ontology and pathway enrichment analysis were performed with the help of the DAVID and KEGG databases, followed by network construction and analysis via Cytoscape. Molecular docking and dynamic simulations were performed to validate the targets of esculetin and phloretin against AKI-diabetes comorbidity. We obtained 6341 targets for AKI-diabetes comorbidity. Further, a total of 54 and 44 targets of esculetin and phloretin against AKI-diabetes comorbidity were retrieved. The top 10 targets for esculetin selected based on the degree value were AKR1B1, DAO, ESR1, PLK1, CA3, CA2, CCNE1, PRKN, HDAC2, and MAOA. Similarly, phloretin's 10 key targets were ACHE, CDK1, MAPK14, APP, CDK5R1, CCNE1, MAOA, MAOB, HDAC6, and PRKN. These targets were enriched in 58 pathways involved in the pathophysiology of AKI-diabetes comorbidity. Further, esculetin and phloretin showed an excellent binding affinity for these critical targets. The findings of this study suggest that esculetin and phloretin combination as a multicomponent multitarget therapy has the potential to prevent AKI-diabetes comorbidity.

CX3CR1-Fractalkine Dysregulation Affects Retinal GFAP Expression, Inflammatory Gene Induction, and LPS Response in a Mouse Model of Hypoxic Retinopathy

Diabetic retinopathy (DR) causes vision loss due to sustained inflammation and vascular damage. The vascular damage is evident by fibrinogen leakage, angiogenesis, and hypoxia. Neuronal regulation of microglia via the CX3CL1 (Fractalkine or FKN)-CX3CR1 pathway plays a significant role in retinal pathology. Defects in FKN or CX3CR1 exacerbate inflammation, vascular damage, and vision impairment. However, the contribution of hypoxic astrocytes to the pathological process of DR is unclear. A hypoxic model (7 days of systemic 7.5% O2) was utilized to induce retinal damage in adult mice in the absence of systemic inflammatory signals. This model induced vascular and microglial responses similar to 10 weeks of STZ-induced hyperglycemia. The goal of this study is to characterize retinal damage in WT and mice with defects in the FKN-CX3CR1 signaling axis and hence assess the impact of the microglial inflammatory responses to hypoxic retinopathy. Tissues were analyzed by immunostaining, RNA sequencing, and cytokine quantification. We found that CX3CR1 deficiency in hypoxic animals induced reactive astrogliosis and that Müller glial responses to hypoxia and systemic inflammation were dependent on FKN signaling. Exacerbated microglial reactivity to hypoxic conditions significantly altered the expression of HIF transcripts. Microglial dysregulation was found to reduce the anti-inflammatory response to hypoxic conditions, downregulate hypoxia-responsive gene expression, and restrained LPS-induced inflammatory responses. We found that microglia dysregulation alters the hypoxic response by inhibiting the upregulation of HIF2α/3α, increasing CD31 immunoreactivity, and altering the expression of ECM-associated transcripts such as type I, III, and XVIII collagens to hypoxic conditions.

Natural compound phloretin restores periodontal immune homeostasis via HIF-1α-regulated PI3K/Akt and glycolysis in macrophages

Periodontitis is a chronic inflammatory disease that affects about 45 %-50 % of adults worldwide, but the efficacy of current clinical therapies is unsatisfactory due to the complicated periodontal immune microenvironment. Thus, developing drugs that can regulate innate immune cells (e.g., macrophages) is a potent strategy to treat periodontitis. Here, we report that phloretin, a food plant-derived natural compound, is sufficient to alleviate periodontitis through immune regulation. In vivo, phloretin treatment could significantly reduce alveolar bone resorption and periodontal inflammation in mouse periodontitis models. In vitro, phloretin could suppress proinflammatory (M1-like) polarization and cytokine release in macrophages induced by LPS. Mechanistically, the immune regulatory role of phloretin in macrophages may be due to its metabolic regulation effect. Phloretin might restore the balance of M1/M2 macrophage transition in periodontitis by inhibiting HIF-1α-mediated glycolysis and PI3k/Akt pathways, thereby reducing the proinflammatory effect and immune disorder caused by over-activated M1 macrophages. Together, this study highlights that natural compound, such as phloretin, can restore periodontal immune homeostasis by metabolic regulation of macrophages, which may provide novel insight into the treatment of periodontitis.

The mechanism and therapeutic strategies in doxorubicin-induced cardiotoxicity: Role of programmed cell death

Doxorubicin (DOX) is the most commonly used anthracycline anticancer agent, while its clinical utility is limited by harmful side effects like cardiotoxicity. Numerous studies have elucidated that programmed cell death plays a significant role in DOX-induced cardiotoxicity (DIC). This review summarizes several kinds of programmed cell death, including apoptosis, pyroptosis, necroptosis, autophagy, and ferroptosis. Furthermore, oxidative stress, inflammation, and mitochondrial dysfunction are also important factors in the molecular mechanisms of DIC. Besides, a comprehensive understanding of specific signal pathways of DIC can be helpful to its treatment. Therefore, the related signal pathways are elucidated in this review, including sirtuin deacetylase (silent information regulator 2 [Sir2]) 1 (SIRT1)/nuclear factor erythroid 2-related factor 2, SIRT1/Klotho, SIRT1/Recombinant Sestrin 2, adenosine monophosphate-activated protein kinase, AKT, and peroxisome proliferator-activated receptor. Heat shock proteins function as chaperones, which play an important role in various stressful situations, especially in the heart. Thus, some of heat shock proteins involved in DIC are also included. Hence, the last part of this review focuses on the therapeutic research based on the mechanisms above.

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.

An Integrated Network Pharmacology and RNA-seq Approach for Exploring the Protective Effect of Andrographolide in Doxorubicin-Induced Cardiotoxicity

PURPOSE

Doxorubicin (Dox) is clinically limited due to its dose-dependent cardiotoxicity. Andrographolide (Andro) has been confirmed to exert cardiovascular protective activities. This study aimed to investigate protective effects of Andro in Dox-induced cardiotoxicity (DIC).

METHODS

The cardiotoxicity models were induced by Dox in vitro and in vivo. The viability and apoptosis of H9c2 cells and the myocardial function of c57BL/6 mice were accessed with and without Andro pretreatment. Network pharmacology and RNA-seq were employed to explore the mechanism of Andro in DIC. The protein levels of Bax, Bcl2, NLRP3, Caspase-1 p20, and IL-1β were qualified as well.

RESULTS

In vitro, Dox facilitated the downregulation of cell viability and upregulation of cell apoptosis, after Andro pretreatment, the above symptoms were remarkably reversed. In vivo, Andro could alleviate Dox-induced cardiac dysfunction and apoptosis, manifesting elevation of LVPWs, LVPWd, EF% and FS%, suppression of CK, CK-MB, c-Tnl and LDH, and inhibition of TUNEL-positive cells. Using network pharmacology, we collected and visualized 108 co-targets of Andro and DIC, which were associated with apoptosis, PI3K-AKT signaling pathway, and others. RNA-seq identified 276 differentially expressed genes, which were enriched in response to oxidative stress, protein phosphorylation, and others. Both network pharmacology and RNA-seq analysis identified Tap1 and Timp1 as key targets of Andro in DIC. RT-QPCR validation confirmed that the mRNA levels of Tap1 and Timp1 were consistent with the sequenced results. Moreover, the high expression of NLRP3, Caspase-1 p20, and IL-1β in the Dox group was reduced by Andro.

CONCLUSIONS

Andro could attenuate DIC through suppression of Tap1 and Timp1 and inhibition of NLRP3 inflammasome activation, serving as a promising cardioprotective drug.