Food therapy of scutellarein ameliorates pirarubicin‑induced cardiotoxicity in rats by inhibiting apoptosis and ferroptosis through regulation of NOX2‑induced oxidative stress

Pirarubicin (THP) is one of the most commonly used antineoplastic drugs in clinical practice. However, its clinical application is limited due to its toxic and heart‑related side effects. It has been reported that oxidative stress, inflammation and apoptosis are closely associated with cardiotoxicity caused by pirarubicin (CTP). Additionally, it has also been reported that scutellarein (Sc) exerts anti‑inflammatory, antioxidant, cardio‑cerebral vascular protective and anti‑apoptotic properties. Therefore, the present study aimed to investigate the effect of food therapy with Sc on CTP and its underlying molecular mechanism using echocardiography, immunofluorescence, western blot, ROS staining, and TUNEL staining. The in vivo results demonstrated that THP was associated with cardiotoxicity. Additionally, abnormal changes in the expression of indicators associated with oxidative stress, ferroptosis and apoptosis were observed, which were restored by Sc. Therefore, it was hypothesized that CTP could be associated with oxidative stress, ferroptosis and apoptosis. Furthermore, the in vitro experiments showed that Sc and the NADPH oxidase 2 (NOX2) inhibitor, GSK2795039 (GSK), upregulated glutathione peroxidase 4 (GPX4) and inhibited THP‑induced oxidative stress, apoptosis and ferroptosis. However, cell treatment with the ferroptosis inhibitor, ferrostatin‑1, or inducer, erastin, could not significantly reduce or promote, respectively, the expression of NOX2. However, GSK significantly affected ferroptosis and GPX4 expression. Overall, the results of the present study indicated that food therapy with Sc ameliorated CTP via inhibition of apoptosis and ferroptosis through regulation of NOX2‑induced oxidative stress, thus suggesting that Sc may be a potential therapeutic drug against CTP.

Rational design of mitochondria-targeted fluorescent biosensors for in vivo elucidation of the interaction between breast cancer metastasis and mitochondrial autophagy

Breast cancer lung metastases (BCLM) are a major cause of high mortality in patients. The shortage of therapeutic targets and rapid drug screening tools for BCLM is a major challenge at present. Mitochondrial autophagy, which involves the degradation of proteins associated with cancer cell aggressiveness, represents a possible therapeutic approach for the treatment of BCLM. Herein, four fluorescent biosensors with different alkyl chains were designed and synthesized to monitor mitochondrial autophagy. Among them, PMV-12 demonstrated the highest sensitivity to viscosity variance, the least impact on polarity, and the longest imaging time. The introduction of the C12-chain made PMV-12 anchored in the mitochondrial membrane without being disturbed by changes of the mitochondrial membrane potential (MMP), thereby achieving the long-term monitor in situ for mitochondrial autophagy. Mitochondria stained with PMV-12 induced swelling and viscosity increase after treating with apigenin, which indicated that apigenin is a potential mitochondrial autophagy inducer. Apigenin was subsequently verified to inhibit cancer cell invasion by 92%. Furthermore, PMV-12 could monitor the process of BCLM in vivo and evaluate the therapeutic effects of apigenin. This work provides a fluorescent tool for elucidating the role of mitochondrial autophagy in the BCLM process and for anti-metastatic drug development.

Scutellarin activates IDH1 to exert antitumor effects in hepatocellular carcinoma progression

Isochlorate dehydrogenase 1 (IDH1) is an important metabolic enzyme for the production of α-ketoglutarate (α-KG), which has antitumor effects and is considered to have potential antitumor effects. The activation of IDH1 as a pathway for the development of anticancer drugs has not been attempted. We demonstrated that IDH1 can limit glycolysis in hepatocellular carcinoma (HCC) cells to activate the tumor immune microenvironment. In addition, through proteomic microarray analysis, we identified a natural small molecule, scutellarin (Scu), which activates IDH1 and inhibits the growth of HCC cells. By selectively modifying Cys297, Scu promotes IDH1 active dimer formation and increases α-KG production, leading to ubiquitination and degradation of HIF1a. The loss of HIF1a further leads to the inhibition of glycolysis in HCC cells. The activation of IDH1 by Scu can significantly increase the level of α-KG in tumor tissue, downregulate the HIF1a signaling pathway, and activate the tumor immune microenvironment in vivo. This study demonstrated the inhibitory effect of IDH1-α-KG-HIF1a on the growth of HCC cells and evaluated the inhibitory effect of Scu, the first IDH1 small molecule agonist, which provides a reference for cancer immunotherapy involving activated IDH1.

Systemic meta-analysis: apigenin's effects on lung inflammation and oxidative stress

OBJECTIVE

This study aimed to investigate the potential anti-inflammatory and antioxidant effects of apigenin in rats with acute lung injury (ALI). We also examined changes in levels of inflammatory and antioxidant factors after apigenin treatment in a rat model of ALI.Methods: We searched several databases, including PubMed, Scopus, EMBASE, Web of Science, ProQuest, and GoogleScholar, to retrieve relevant articles for our systematic review and meta-analysis.Five studies with 226 rat models of ALI were included in this study. We investigated inflammatory factors and oxidative stress with the corresponding 95% confidence interval in three groups: 1. Group1 (control vs. ALI), 2. Group2 (ALI vs. apigenin10), and 3. Group3 (ALI vs. apigenin20).

RESULTS

Estimating the correlation and 95% confidence intervals for the inflammatory agents and oxidative stress in the intervention group (ALI), compared with that in the control group, respectively (correlation: 0.194; 95% confidence intervals, 0.101-0.282, p value = .001, z-value= 4.08) and (correlation: 0.099; 95% confidence intervals, 0.016-0.182, p value = .020, z value= 2.325). Estimating the correlation and 95% confidence intervals for the inflammatory agents and oxidative stress in the intervention group (apigenin 10 mg/kg), compared with that in the control group (ALI), respectively (correlation: 0.476; 95% confidence intervals, 0.391-0.553, p value = .001, z-value= 9.678) and (correlation: 0.415; 95% confidence intervals, 0.313-0.508, p value= .001, z-value= 7.349).

CONCLUSION

Apigenin may have potential anti-inflammatory and antioxidant effects in rat models of ALI. However, the efficacy of apigenin as a therapeutic strategy requires further investigation through prospective controlled randomized trials.

Apigenin Self-Assembled Collagen Biomatrix for Reprogramming the Obese Wound Microenvironment for Its Management and Repair

Wound management in obesity is complicated by excessive exudates from wounded areas, pressure ulcerations due to stacking of the fat layer, and vascular rarefaction. The current study explored the development of biomaterials for reprogramming the altered wound microenvironment under obese conditions. Self-assembled collagen biomatrix with trans and de novo browning activator, apigenin, was fabricated as a soft tissue regenerative wound dressing material. The as-synthesized self-assembled collagen biomatrix exhibited excellent thermal, mechanical, and biological stability with a superior wound exudate absorption capacity. The apigenin self-assembled collagen biomatrix exhibited porous 3-D microstructure that mimicked the extracellular matrix that promoted cell adhesion and proliferation. The apigenin self-assembled collagen multifunctional biomatrix triggered adaptive localized thermogenesis in the subcutaneous fat layer, resulting in the activation of angiogenesis and fibroblast spreading and migration. The in vivo wound healing assay performed in DIO-C57BL6 mice showed faster tissue regeneration within 9 days, with well-defined neo-epidermis, blood vessel formation, thick collagen deposition, minimal inflammation, and significant activation of browning in the subcutaneous adipose layer. This study paves the way forward for the development of specialized regenerative biomatrices that reprogram the obese wound bed for faster tissue regeneration.

Apigenin Suppresses Innate Immune Responses and Ameliorates Lipopolysaccharide-Induced Inflammation via Inhibition of STING/IRF3 Pathway

The stimulator of interferon genes (STING) signaling pathway is crucial for the pathogenesis of autoimmune and inflammatory disorders, including acute lung injury (ALI). Apigenin (4[Formula: see text],5,7-trihydroxyflavone) is a natural flavonoid widely found in fruits, vegetables, and Chinese medicinal herbs that exhibits a range of pharmacological effects, such as antibacterial and anti-inflammatory activities. However, the efficacy of apigenin in STING pathway-mediated diseases remains unclear. Accordingly, this study screened Chinese medicines to identify potent agents that reduced the synthesis of type I interferons (IFNs). The results revealed apigenin as a potent compound with low cytotoxicity that markedly reduced the synthesis of type I IFNs in response to STING pathway agonists. Besides, apigenin markedly suppressed innate immune responses triggered by the STING agonist SR-717. Mechanistically, apigenin downregulated IFN beta 1 (IFNB1) expression mediated by the STING pathway via dose-dependent inhibition of STING expression, reduction of dimerization, nuclear translocation of phosphorylated IRF3, and disruption of the association between STING and IRF3. Moreover, apigenin effectively mitigated pathological pulmonary inflammation and lung edema in lipopolysaccharide (LPS)-induced ALI in mice. Apigenin further strongly attenuated the hallmarks of immoderate inflammation (interleukin (IL)-6, IL-1[Formula: see text], and tumor necrosis factor [Formula: see text]) and innate immune responses (IFNB1, C-X-C motif chemokine ligand 10, and IFN-stimulated gene 15) by preventing the activation of the STING/IRF3 pathway both in vitro and in vivo. Importantly, SR-717 significantly reversed the inhibitory effects of apigenin in LPS-induced THP1-BlueTM ISG macrophages. Collectively, apigenin effectively alleviated innate immune responses and mitigated inflammation in LPS-induced ALI via inhibition of the STING/IRF3 pathway. These findings suggest the potential of apigenin as a prophylactic and therapeutic candidate for managing STING-mediated diseases.

Apigenin ameliorates genitourinary dysfunction in a type 1 diabetic rat model via Drp1 modulation

The present study aimed to explore the potential ameliorative effect of apigenin (APG) against diabetes-associated genitourinary complications in rats. A diabetic rat model was induced by the intraperitoneal injection of streptozotocin (STZ). All experimental animals were treated with vehicle or vehicle plus APG at a dose of 0.78 mg/kg/day for 10 days, either once diabetes was confirmed or at the end of the 3rd week after confirmation of diabetes. Rats were sacrificed at the end of the fifth week. In addition to the histological assessment, an analysis of kidney function tests and serum testosterone was performed to assess diabetic genitourinary complications. Gene expression of the mitochondrial fission protein, dynamin related protein 1 (Drp1), was measured in renal and testicular tissues using qRT PCR. APG can increase body weight, reduce blood glucose levels, and improve renal and testicular functions in diabetic rats. APG decreased Drp1 overexpression in diabetic animals' kidneys and testes. In summary, our current work discloses that APG attenuates diabetic genitourinary lesions in rats via suppressing Drp1 overexpression.

Apigenin and Temozolomide Synergistically Inhibit Glioma Growth Through the PI3K/AKT Pathway

Background: Glioma is a devastating disease with the worst prognosis among human malignant tumors. Although temozolomide (TMZ) improves the overall survival of glioma patients, there are still many glioma patients who are resistant to TMZ. In this study, we focused on the effect of apigenin (API) and TMZ on glioma cells in vitro and in vivo, and we studied the underlying molecular mechanisms. Materials and Methods: To investigate the effect of API on glioblastoma cell proliferation, cell viability was assessed after glioma cells were incubated with various concentrations of API with or without TMZ using MTT assays. Then, we explored the synergistic effect of API and TMZ on glioma cell cycle, apoptosis, and migration. To investigate the molecular mechanism behind the synergism of API and TMZ, we examined the related genes of the major signaling pathways involved in glioma pathogenesis by Western blotting. Results: In this study, we found that API significantly suppressed the proliferation of glioma cells in a dose- and time-dependent manner. Combining API and TMZ significantly induced glioma cells arrest at the G2 phase and inhibited glioma cells proliferation compared with API or TMZ alone. In addition, API promoted the ability of TMZ to induce glioma cells apoptosis and inhibit glioma cells invasion. Furthermore, compared with treatment with individual agents, the combination of API and TMZ significantly inhibited the growth of subcutaneous tumors in mice. These results implied that API could synergistically suppress the growth of glioma cells when combined with TMZ. Combining API and TMZ significantly inhibited the protein expression of p-AKT, cyclin D1, Bcl-2, Matrix Metallopeptidase 2, and Matrix Metallopeptidase 9. Conclusion: API and TMZ synergistically inhibited glioma growth through the PI3K/AKT pathway.

Apigenin analogs as α-glucosidase inhibitors with antidiabetic activity

This study investigated the inhibitory potential of a series of synthesized compounds (L1-L27) on α-glucosidase. Among them, compound L22 showed significant inhibitory effect. Through enzymatic kinetics studies, we demonstrated that L22 acts via a non-competitive inhibition mode with a Ki value of 2.61 μM, highlighting its high affinity for the enzyme. Molecular docking studies revealed the formation of hydrogen bonds between L22 and α-glucosidase and diverse interactions with neighboring amino acid residues. Furthermore, molecular dynamics simulations confirmed the stability of the L22-α-glucosidase complex. In a mouse model of type 2 diabetes, treatment with L22 significantly lowered fasting blood glucose levels, and reduced insulin resistance, suggesting its potential as a therapeutic agent for type 2 diabetes. Furthermore, L22 showed a protective effect against oxidative stress in the liver and alleviated liver and pancreatic abnormalities. These results provide valuable insights into the mechanism of action of L22 and its potential applications to treat type 2 diabetes, and improve liver health.

The Effects of Apigenin in the Treatment of Diabetic Nephropathy: A Systematic Review of Non-clinical Studies

PURPOSE

Diabetes is one of the important and growing diseases in the world. Among the most common diabetic complications are renal adverse effects. The use of apigenin may prevent the development and progression of diabetes-related injuries. The current study aims to review the effects of apigenin in the treatment of diabetic nephropathy.

METHODS

In this review, a systematic search was performed based on PRISMA guidelines for obtaining all relevant studies on "the effects of apigenin against diabetic nephropathy" in various electronic databases up to September 2022. Ninety-one articles were obtained and screened in accordance with the predefined inclusion and exclusion criteria. Seven eligible articles were finally included in this review.

RESULTS

The experimental findings revealed that hyperglycemia led to the decreased cell viability of kidney cells and body weight loss and an increased kidney weight of rats; however, apigenin administration had a reverse effect on these evaluated parameters. It was also found that hyperglycemia could induce alterations in the biochemical and renal function-related parameters as well as histopathological injuries in kidney cells or tissue; in contrast, the apigenin administration could ameliorate the hyperglycemia-induced renal adverse effects.

CONCLUSION

The results indicated that the use of apigenin could mitigate diabetes-induced renal adverse effects, mainly through its antioxidant, anti-apoptotic, and anti-inflammatory activities. Since the findings of this study are based on experimental studies, suggesting the use of apigenin (as a nephroprotective agent) against diabetic nephropathy requires further clinical studies.

Effect of Apigenin on Neurodegenerative Diseases

Neurodegenerative diseases (NDDs), such as Alzheimer's and Parkinson's, are the most frequent age-related illnesses affecting millions worldwide. No effective medication for NDDs is known to date and current disease management approaches include neuroprotection strategies with the hope of maintaining and improving the function of neurons. Such strategies will not provide a cure on their own but are likely to delay disease progression by reducing the production of neurotoxic chemicals such as reactive oxygen species (ROS) and related inflammatory chemicals. Natural compounds such as flavonoids that provide neuroprotection via numerous mechanisms have attracted much attention in recent years. This review discusses evidence from different research models and clinical trials on the therapeutic potential of one promising flavonoid, apigenin, and how it can be helpful for NDDs in the future prospects. We have also discussed its chemistry, mechanism of action, and possible benefits in various examples of NDDs.

Postischemic Infusion of Apigenin Reduces Seizure Burden in Preterm Fetal Sheep

Seizures are common in preterm newborns and are associated with poor neurodevelopmental outcomes. Current anticonvulsants have poor efficacy, and many have been associated with upregulation of apoptosis in the developing brain. Apigenin, a natural bioactive flavonoid, is a potent inhibitor of hyaluronidase and reduces seizures in adult animal models. However, its impact on perinatal seizures is unclear. In the present study, we examined the effect of apigenin and S3, a synthetic, selective hyaluronidase inhibitor, on seizures after cerebral ischemia in preterm fetal sheep at 0.7 gestation (98-99 days, term ~147 days). Fetuses received sham ischemia (n = 9) or ischemia induced by bilateral carotid occlusion for 25 min. Immediately after ischemia, fetuses received either a continuous infusion of vehicle (0.036% dimethyl sulfoxide, n = 8) or apigenin (50 µM, n = 6). In a pilot study, we also tested infusion of S3 (2 µM, n = 3). Fetuses were monitored continuously for 72 h after ischemia. Infusion of apigenin or S3 were both associated with reduced numbers of animals with seizures, total seizure time, and mean seizure burden. S3 was also associated with a reduction in the total number of seizures over the 72 h recovery period. In animals that developed seizures, apigenin was associated with earlier cessation of seizures. However, apigenin or S3 treatment did not alter recovery of electroencephalographic power or spectral edge frequency. These data support that targeting brain hyaluronidase activity with apigenin or S3 may be an effective strategy to reduce perinatal seizures following ischemia. Further studies are required to determine their effects on neurohistological outcomes.

Effect of a Flavonoid Combination of Apigenin and Epigallocatechin-3-Gallate on Alleviating Intestinal Inflammation in Experimental Colitis Models

Inflammatory bowel disease (IBD) is an autoimmune disease that leads to severe bowel symptoms and complications. Currently, there is no effective treatment, and the exact cause of IBD remains unclear. In the last decades, numerous studies have confirmed that flavonoids can have a positive impact on the treatment of IBD. Therefore, this study investigated the protective effect of a flavonoid combination of apigenin and epigallocatechin-3-gallate (EGCG) on IBD. In vitro studies in which Caco-2 cell monolayers were incubated with different concentrations of flavonoids found that the flavonoid-treated group exhibited increased transepithelial electrical resistance (TEER) at high concentrations, indicating a protective effect on the barrier function of the intestinal epithelium. In vivo studies showed that flavonoids significantly attenuated inflammatory levels in both chronic and acute hapten-mediated experimental colitis models in a time- and dose-dependent manner. In addition, the activity of myeloperoxidase (MPO) and the level of proinflammatory cytokines in the colon tissue were significantly reduced. Interestingly, the levels of anti-inflammatory cytokines were also dramatically increased. Finally, flavonoids were found to positively modulate the composition of the gut microbiota in the colon. Therefore, a combination of flavonoids could be a promising therapeutic agent for the future adjunctive treatment of IBD.

Apigenin attenuates visceral hypersensitivity in water avoidance stress rats by modulating the microbiota-gut-brain axis and inhibiting mast cell activation

Visceral hypersensitivity (VH) and gut microbiota dysbiosis significantly contribute to the occurrence and development of irritable bowel syndrome (IBS), exacerbated by stress. Apigenin, a natural flavonoid derived from plants, possesses a range of beneficial properties. However, additional research is necessary to investigate its potential in alleviating symptoms of IBS and elucidating its underlying mechanisms of action. Our study confirms that apigenin effectively reverses mast cell and microglial activation, regulates the composition and abundance of the gut microbiota, improves intestinal barrier function in rats induced with water-avoidance stress, and mitigates VH and colonic hypermotility. Furthermore, in vitro studies suggest a potential role of dysbiotic gut microbiota in activating mast cells at the cellular level. Notably, apigenin inhibits mast cell degranulation through the toll-like receptor 4 (TLR4) / myeloid differentiation primary response gene 88 (MyD88) / nuclear factor-kappa B (NF-κB) pathway. In conclusion, this study discusses the potential therapeutic effects of apigenin in alleviating VH and modulating the gut-brain axis in water-avoidance stress rats, providing a novel or alternative treatment approach for IBS.

The interaction between apigenin and PKM2 restrains progression of colorectal cancer

Apigenin, a flavonoid that widely existed in vegetables and fruits, possesses anticarcinogenic, low toxicity, and no mutagenic properties, suggesting that apigenin is a potential therapeutic agent for tumors. However, the underlying anti-cancer molecular target of apigenin is still unclear. Therefore, to reveal the direct target and amino acid site of apigenin against colorectal cancer is the focus of this study. In the present study, the results proved that the anti-CRC activity of apigenin was positively correlated with pyruvate kinase M2 (PKM2) expression, characterized by the inhibition of cell proliferation and increase of apoptotic effects induced by apigenin in LS-174T cells of knock down PKM2. Next, pull-down and MALDI-TOF/TOF analysis determined that apigenin might interact directly with PKM2 in HCT-8 cells. Further, the study confirmed that lysine residue 433 (K433) was a key amino acid site for PKM2 binding to apigenin. Apigenin restricted the glycolysis of LS-174T and HCT-8 cells by targeting the K433 site of PKM2, thereby playing an anti-CRC role in vivo and in vitro. Meanwhile, apigenin markedly attenuated tumor growth without any adverse effects. Taken together, these findings reveal that apigenin is worthy of consideration as a promising PKM2 inhibitor for the prevention of CRC.

Anti-influenza drug screening and inhibition of apigetrin on influenza A virus replication via TLR4 and autophagy pathways

Activation of Toll-like receptor (TLR) 4 plays important roles in the influenzaA virus (IAV) infection. To explore TLR4 inhibitors, 161 traditional Chinese medicines (TCMs) were screened. Further, we screened out Ixeris sonchifolia Hance, and its active compound, Apigetrin (apigenin-7-O-glucoside). Antiviral activity of Apigetrin was determined by plaque assay. We also further investigated the influence of Apigetrin on immune signaling pathways including TLRs, MAPK, NF-κB and autophagy pathways. The in-vitro results showed that the extract and its several ingredients could significantly inhibit IAV replication. Apigetrin significantly improved IAV-induced oxidative stress, inhibited the IAV-induced cytokine storm by suppressing the excessive activation of TLR3/4/7, JNK/p38 MAPK and NF-κB. Apigetrin decreased autophagosome accumulation and promoted degradation of IAV protein. Interestingly, Apigetrin antiviral activity was reversed by using H2O2 and the agonists of TLR4, JNK/p38, NF-κB and autophagy. Most important, the in-vitro effective concentration is higher than the reported plasma concentration. The in-vivo test showed that Apigetrin significantly increased the average survival time, reduced the lung edema and IAV replication. In conclusion, we have found that Ixeris sonchifolia Hance and its several ingredients can inhibit IAV infection, and the mechanisms of action of Apigetrin against IAV is by regulating TLR4 and autophagy signaling pathways.

Apigenin's Therapeutic Potential Against Viral Infection

Several antiviral drugs are clinically approved to treat influenza that is a highly prevalent acute respiratory disease. However, emerging drug-resistant virus strains undermine treatment efficacy, highlighting the exigency for novel antiviral drugs to counter these drug-resistant strains. Plants and their derivates have been historically utilized as medicinal remedies, and extensive studies have evidenced the antiviral potential of phytochemicals. Notably, apigenin is a predominant flavonoid with minimal toxicity and substantial therapeutic effects in various disease models. Despite its many anti-inflammatory, anti-oxidant, anti-cancer, anti-bacterial, and other beneficial bioactivities, existing reviews have yet to focus on apigenin's antiviral effects. Therefore, this review elucidates apigenin's therapeutic and antiviral properties in vitro and in vivo, discussing its mode of action and future prospects. Apigenin's remarkable inhibition by modulating multiple mechanisms against viruses has promising potential for novel plant-derived antiviral drugs and further clinical study developments.

Screening of an FDA-approved compound library identifies apigenin for the treatment of myocardial injury

Apigenin is the active ingredient in Ludangshen. Although previous studies reported the cardioprotective actions of apigenin against doxorubicin (Dox)-induced cardiomyopathy, the underlying mechanisms remain incompletely understood. Since apigenin beneficially regulates various aspects of mitochondrial function and dynamics, we asked whether apigenin improves heart function in mice with Dox-induced cardiomyopathy by regulating the mitochondrial unfolded protein response (UPRmt). Co-administration of apigenin significantly restored heart function, reduced myocardial swelling, inhibited cardiac inflammation, increased cardiac transcription of UPRmt-related genes, and promoted cardiomyocyte survival in Dox-treated mice. In turn, blockade of UPRmt abolished the mito- and cytoprotective effects of apigenin, evidenced by decreased ATP production, suppressed mitochondrial antioxidant capacity, and increased apoptosis, in Dox-treated, cultured HL-1 cardiomyocytes. Furthermore, apigenin treatment prevented Dox-induced downregulation of Sirt1 and Atf5 expression, and the beneficial effects of apigenin were completely nullified in Sirt1 knockout (KO) mice or after siRNA-mediated Sirt1 knockdown in vitro. We thus provide novel evidence for a promotive effect of apigenin on UPRmt via regulation of the Sirt1/Atf5 pathway. Our findings uncover that apigenin seems to be an effective therapeutic agent to alleviate Dox-mediated cardiotoxicity.

Biostimulated-sesame sprout extracts as potential agents against Leishmania mexicana

Leishmania mexicana is one of the causal agents of cutaneous leishmaniasis. Current antileishmanial chemotherapeutics have demonstrated adverse side effects; thus, alternative treatments are needed. In this study, we performed in silico and in vitro analyses of the leishmanicidal potential of the most abundant phenolic compounds identified in black sesame sprouts biostimulated with Bacillus clausii. The molecular docking analysis showed strong interactions (binding free energies between -6.5 and -9.5 kcal/mol) of sesaminol 2-O-triglucoside, pinoresinol dihexoside, isoverbascoside, and apigenin with the arginase, leishmanolysin, cysteine peptidase B, and pyruvate kinase leishmanial enzymes. Furthermore, almost all phenolic compounds interacted with the active site residues of L. mexicana enzymes. In vitro, the B. clausii-biostimulated sprout phenolic extracts and apigenin inhibited the growth of promastigotes with IC50 values of 0.08 mg gallic acid equivalent/mL and 6.42 μM (0.0017 mg/mL), respectively. Additionally, in the macrophage infection model, cells treated with B. clausii-biostimulated sprout phenolic extracts and infected with L. mexicana exhibited significantly (P < 0.05) reduced nitric oxide production and decreased parasite burden. Altogether, our study provides important data related to high efficacy and less toxic natural antileishmanial candidates against promastigotes of L. mexicana.

The effect of Apigenin on glycometabolism and cell death in an anaplastic thyroid cancer cell line

AIMS AND BACKGROUND

A more pronounced characteristic of cancer cells is the energy dependence on glucose, which mitigated by glucose transporters. The comprehension of the regulatory mechanisms behind the Warburg effect holds promise for developing therapeutic interventions for cancers. Studies are lacking which targeted the GLUTs for treatment of malignancy of thyroid tumors. In our current investigation, we have undertaken this study to determine the potential of Apigenin, plant derived flavonoid in modulating tumor apoptosis by targeting GLUTs expression in SW1736 cell line of anaplastic thyroid carcinoma.

MATERIAL METHODS

Flow cytometry with propidium iodide staining was used to determine cell apoptosis. For glucose uptake detection, the "GOD-PAP" enzymatic colorimetric test was used to measure the direct glucose levels inside the cells. To determine the expression of GLUT1 and GLUT3 mRNA in the SW1736 cell line qRT-PCR was employed. Protein levels of GLUT1 and GLUT3 in the SW1736 cell line were detected with western blotting. Also, the scratch wound healing assay was conducted for cell migration.

RESULTS

According to qRT-PCR analysis, the levels of GLUT1 and GLUT3 mRNA were lower in the group that received Apigenin relative to the control group. The Apigenin treatment of SW1736 cells decreased protein expression of the GLUT1 and GLUT3 levels in conformity to qRT-PCR. The scratch assays revealed that Apigenin treatment of cancer cell lines inhibited cell migration as compared to control.

CONCLUSION

These findings demonstrate the possibility of targeting the glucose facilitators' pathway for making thyroid cancer cells more susceptible to programmed cell death.

Apigenin attenuates inflammatory response in allergic rhinitis mice by inhibiting the TLR4/MyD88/NF-κB signaling pathway

BACKGROUND

Allergic rhinitis (AR) is an immunoglobulin E (IgE)-mediated immune inflammatory response that mainly affects the nasal mucosa. Currently, there is evidence that apigenin, as a flavonoid, has anti-allergic potential.

MATERIAL/METHODS

In vitro, compound 48/80 and lipopolysaccharide (LPS) were used to induce mast cell activation and inflammation in HMC-1 cells. In vivo, ovalbumin (OVA) induced and stimulated AR in BALB/c mice. ELISA was used to detect the contents of β-hexosaminidase, histamine, eosinophil cationic protein (ECP), OVA-specific IgE, IgG1, and IgG2a, inflammatory factors in cells and mouse serum. Cell viability and apoptosis were measured with MTT and flow cytometry. Toll like receptor 4 (TLR4)/myeloid differentiation factor88 (MyD88)/Nuclear transcription factor-κB (NF-κB) pathway-related proteins in cells and mouse nasal mucosa tissues were analyzed with Western blotting. The levels of Th1 (IFN-γ) and Th2 (IL-4, IL-5, and IL-13) cytokines and Th1 (T-bet) and Th2 (GATA-3) specific transcription factors were also assessed. The ratio of Th1 (CD4⁺ IFN-γ⁺ ) / Th2 (CD4⁺ IL-4⁺ ) cells in mouse peripheral blood mononuclear cells was evaluated by flow cytometry.

RESULTS

Apigenin significantly inhibited compound 48/80-induced secretion of β-hexosaminidase and histamine. Apigenin blocked LPS-induced decrease in cell viability and increase in cell apoptosis and inflammatory cytokine secretion by suppressing the activity of the TLR4/MyD88/NF-κB pathway. Apigenin treatment reduced the levels of OVA-specific IgE, IgG1 and IgG2a as well as β-hexosaminidase, histamine and ECP levels in mouse serum. Moreover, administration with apigenin decreased Th2 cytokine and transcription factor levels and increased Th1 cytokine and transcription factor levels, and promoted the ratio of Th1/Th2 cells in AR mice. Additionally, apigenin significantly alleviated nasal symptoms and nasal eosinophil infiltration in AR mice.

CONCLUSIONS

Apigenin alleviates the inflammatory response of allergic rhinitis by inhibiting the activity of the TLR4/MyD88/NF-κB signaling pathway.

Pharmacological and Molecular Insight on the Cardioprotective Role of Apigenin

Apigenin is a naturally occurring dietary flavonoid found abundantly in fruits and vegetables. It possesses a wide range of biological properties that exert antioxidant, anti-inflammatory, anticancer, and antibacterial effects. These effects have been reported to be beneficial in the treatment of atherosclerosis, stroke, hypertension, ischemia/reperfusion-induced myocardial injury, and diabetic cardiomyopathy, and provide protection against drug-induced cardiotoxicity. These potential therapeutic effects advocate the exploration of the cardioprotective actions of apigenin. This review focuses on apigenin, and the possible pharmacological mechanisms involved in the protection against cardiovascular diseases. We further discuss its therapeutic uses and highlight its potential applications in the treatment of various cardiovascular disorders. Apigenin displays encouraging results, which may have implications in the development of novel strategies for the treatment of cardiovascular diseases. With the commercial availability of apigenin as a dietary supplement, the outcomes of preclinical studies may provide the investigational basis for future translational strategies evaluating the potential of apigenin in the treatment of cardiovascular disorders. Further preclinical and clinical investigations are required to characterize the safety and efficacy of apigenin and establish it as a nutraceutical as well as a therapeutic agent to be used alone or as an adjuvant with current drugs.

Apigenin: A Therapeutic Agent for Treatment of Skin Inflammatory Diseases and Cancer

The skin is the main barrier between the body and the environment, protecting it from external oxidative stress induced by ultraviolet rays. It also prevents the entrance of infectious agents such as viruses, external antigens, allergens, and bacteria into our bodies. An overreaction to these agents causes severe skin diseases, including atopic dermatitis, pruritus, psoriasis, skin cancer, and vitiligo. Members of the flavonoid family include apigenin, quercetin, luteolin, and kaempferol. Of these, apigenin has been used as a dietary supplement due to its various biological activities and has been shown to reduce skin inflammation by downregulating various inflammatory markers and molecular targets. In this review, we deal with current knowledge about inflammatory reactions in the skin and the molecular mechanisms by which apigenin reduces skin inflammation.

Potential Antioxidant Activity of Apigenin in the Obviating Stress-Mediated Depressive Symptoms of Experimental Mice

This study aimed to examine the antidepressant properties of apigenin in an experimental mouse model of chronic mild stress (CMS). Three weeks following CMS, albino mice of either sex were tested for their antidepressant effects using the tail suspension test (TST) and the sucrose preference test. The percentage preference for sucrose solution and the amount of time spent immobile in the TST were calculated. The brain malondialdehyde (MDA) levels, catalase activity, and reduced glutathione levels were checked to determine the antioxidant potential of treatments. When compared to the control, animals treated with apigenin during the CMS periods showed significantly shorter TST immobility times. Apigenin administration raised the percentage preference for sucrose solution in a dose-dependent manner, which put it on par with the widely used antidepressant imipramine. Animals treated with apigenin displayed a significantly (p ˂ 0.05) greater spontaneous locomotor count (281) when compared to the vehicle-treated group (245). Apigenin was also highly effective in significantly (p ˂ 0.01) lowering plasma corticosterone levels (17 vs. 28 µg/mL) and nitrite (19 vs. 33 µg/mL) produced by CMS in comparison to the control group. During CMS, a high dose (50 mg/kg) of apigenin was given, which greatly increased the reduced glutathione level while significantly decreasing the brain's MDA and catalase activity when compared to the control group. As a result, we infer that high doses of apigenin may have potential antidepressant effects in animal models via various mechanisms.

Vitexin Protects against Dextran Sodium Sulfate-Induced Colitis in Mice and Its Potential Mechanisms

Vitexin, one of the major active components in hawthorn, has been shown to possess multiple pharmacological activities. Here, we sought to investigate the effect of vitexin on an ameliorating dextran sodium sulfate (DSS)-induced ulcerative colitis (UC) mouse model and further explored its potential mechanism. The results indicated that vitexin administration could significantly alleviate the signs of colitis via suppressing body weight loss, reducing disease activity index (DAI) score, and mitigating colonic damage. Also, vitexin treatment in colitis mice markedly inhibited the production of pro-inflammation cytokines (such as IL-1β, IL-6, and TNF-α). Meanwhile, vitexin also could markedly down-regulate the phosphorylation levels of p65, IκB, and STAT1. Moreover, vitexin also dose-dependently increased the expressions of muc-2, ZO-1, and occludin proteins in colonic tissues of colitis mice. Further studies revealed that vitexin dramatically modulated the disturbed intestinal flora in colitis mice. Vitexin is beneficial for regulating abundances of some certain bacteria, such as Bacteroides, Helicobacter, Alistipes, Lachnospiraceae_NK4A136_group, and Lachnospiraceae_UCG-006. Interestingly, the correlation analysis indicated that key microbes were strongly correlated with colitis features, such as pro-inflammatory cytokines and gut barrier. Collectively, these results demonstrated that vitexin treatment alleviated inflammation, intestinal barrier dysfunction, and intestinal flora dysbiosis in colitis mice. Vitexin is expected to be a promising compound for UC treatment.

Apigenin Attenuates Mesoporous Silica Nanoparticles-Induced Nephrotoxicity by Activating FOXO3a

Mesoporous silica nanoparticles (MSNs) are widely used in many biomedical applications and clinical fields. However, the applications of MSNs are limited by their severe toxicity. Apigenin (AG) has demonstrated pharmacological effects with low toxicity. The aim of this study was to clarify the role of AG in the progression of MSNs-induced renal injury. BALB/c mice and NRK-52E cells were exposed to MSNs with or without AG. AG protected mice and NRK-52E cells from the MSNs-induced pathological variations in renal tissues and decreased cell viability. AG significantly reduced the levels of serum blood urea nitrogen (BUN) and serum creatinine (Scr), upregulated the levels of superoxide dismutase (SOD), glutathione (GSH) and catalase (CAT), and improved the pathological changes of the kidney in MSNs-treated mice. The protective effects of AG were associated with its ability to increase the levels of antioxidants, reduce the accumulation of ROS, and inhibit the expression of the inflammatory mediators (TNF-α, IL-6). In addition, AG treatment upregulated the activity of FOXO3a, increased the level of IkBα, and reduced the nuclear translocation of NF-κB, which ultimately alleviated MSNs-induced inflammation. Nuclear FOXO3a translocation also triggered antioxidant gene transcription and protected nephrocyte from oxidative damage. However, knockdown of FOXO3a significantly blocked the protective effects of AG. These findings suggested that AG could be a promising therapeutic strategy for MSNs-induced nephrotoxicity, and this protective effect might be related to the suppression of oxidative stress and inflammation via the FOXO3a/NF-κB pathway.

Apigenin inhibits isoproterenol‐induced myocardial fibrosis and Smad pathway in mice by regulating oxidative stress and miR‐122‐5p/155‐5p expressions

Apigenin, a flavonoid isolated from Apium graveolens, is an effective natural active ingredient that inhibits transforming growth factor-β1 (TGF-β1)-induced cardiac fibroblasts (CFs) differentiation and collagen synthesis. However, its effects on isoproterenol-induced myocardial fibrosis in mice remain unknown. This study aimed to examine the effect of apigenin in the prevention of myocardial fibrosis. A mouse model of myocardial fibrosis induced by isoproterenol was established, and the mice were given apigenin 75-300 mg/kg orally for 40 days. The results showed that the heart weight coefficient, myocardial hydroxyproline, collagen accumulation, and malondialdehyde levels in the apigenin-treated groups were significantly reduced. In contrast, the activity of myocardial superoxide dismutase and glutathione peroxidase were significantly enhanced. The results of real-time quantitative polymerase chain reaction and western blot assays showed that apigenin could significantly upregulate the expressions of myocardial microRNA-122-5p (miR-122-5p), c-Ski, and Smad7 and downregulate the expressions of myocardial miR-155-5p, α-smooth muscle actin, collagen I/III, NF-κB, TGF-β1, hypoxia-inducible factor-1α (HIF-1α), Smad2/3, and p-Smad2/3. In vitro, the differentiation and extracellular matrix production, as well as TGF-β1/Smads axis, were further reduced after treatment of miR-122-5p mimic or miR-155-5p inhibitor-transfected and TGF-β1-stimulated CFs with apigenin. These results suggested that apigenin increased the expression of miR-122-5p and decreased the expression of miR-155-5p, which subsequently downregulated and upregulated the target genes HIF-1α and c-Ski, respectively. Furthermore, apigenin administration downregulated TGF-β1-induced Smad2/3 and upregulated Smad7. In addition, it reduced the NF-κB/TGF-β1 signaling pathway axis by increasing antioxidant ability to exert the antifibrotic effects.

Kaempferol and Apigenin suppresses the stemness properties of TNBC cells by modulating Sirtuins

Sirtuins (SIRTs) overexpression serves as a potential therapeutic target for TNBC because it is associated with bioactivities of cancer stem cells (CSCs), resistance to chemotherapy, and metastasis. Irrespective of the availability of synthetic SIRT inhibitors, new SIRT inhibitors with enhanced potency and lesser side effects serve as current unmet needs. Therefore, bioactive dietary compounds; kaempferol (KMP) and apigenin (API) were investigated for their anti-SIRTs potential. We observed KMP and API inhibits cellular proliferation by DNA damage and S-phase cell cycle arrest in TNBC Cells. They also suppress stemness properties in TNBCs as observed in experiments of mammosphere formation and clonogenic potential. Our mechanistic approach indicated that KMP and API inhibited SIRT3 and SIRT6 proteins, as evidenced by our in silico and in vitro experiment. Collectively, our studies suggest that KMP and API are promising candidates to be further developed as sirtuin modulators against TNBCs.

Effect of Hibiscus syriacus Linnaeus extract and its active constituent, saponarin, in animal models of stress-induced sleep disturbances and pentobarbital-induced sleep

Treatment of sleep disorders promotes the long-term use of commercially available sleep inducers that have several adverse effects, including addiction, systemic fatigue, weakness, loss of concentration, headache, and digestive problems. Therefore, we aimed to limit these adverse effects by investigating a natural product, the extract of the Hibiscus syriacus Linnaeus flower (HSF), as an alternative treatment. In the electric footshock model, we measured anxiety and assessed the degree of sleep improvement after administering HSF extract. In the restraint model, we studied the sleep rate using PiezoSleep, a noninvasive assessment system. In the pentobarbital model, we measured sleep improvement and changes in sleep-related factors. Our first model confirmed the desirable effects of HSF extract and its active constituent, saponarin, on anxiolysis and Wake times. HSF extract also increased REM sleep time. Furthermore, HSF extract and saponarin increased the expression of cortical GABAA receptor α1 (GABAAR α1) and c-Fos in the ventrolateral preoptic nucleus (VLPO). In the second model, HSF extract and saponarin restored the sleep rate and the sleep bout duration. In the third model, HSF extract and saponarin increased sleep maintenance time. Moreover, HSF extract and saponarin increased cortical cholecystokinin (CCK) mRNA levels and the expression of VLPO c-Fos. HSF extract also increased GABAAR α1 mRNA level. Our results suggest that HSF extract and saponarin are effective in maintaining sleep and may be used as a novel treatment for sleep disorder. Eventually, we hope to introduce HSF and saponarin as a clinical treatment for sleep disorders in humans.

Neuroprotective Effect of Apigenin on Depressive-Like Behavior: Mechanistic Approach

Apigenin, as a natural flavonoid present in several plants is characterized with potential anticancer, antioxidant, and anti-inflammatory properties. Recent studies proposed that apigenin affects depression disorder through unknown mechanistic pathways. The effects of apigenin's anti-depressive properties on streptozocin-mediated depression have been investigated through the evaluation of behavioral tests, oxidative stress, cellular energy homeostasis and inflammatory responses. The results demonstrated anti-depressive properties of apigenin in behavioral test including forced swimming and splash tests and oxidative stress biomarkers such as reduced glutathione, lipid peroxidation, total antioxidant power and coenzyme Q₁₀ levels. Apigenin, also, demonstrated its regulatory potency in cellular energy homeostasis and immune system gene expression through inhibiting Nlrp3 and Tlr4 overexpression. Furthermore, failure in energy production as the key factor in various psychiatric disorders was reversed by apigenin modulating effect on AMPK gene expression. Overall, 20 mg/kg of apigenin was recognized as the dose suitable for minimizing the undesirable adverse effects in the STZ-mediated depression model proposed in this study. Our data suggested that apigenin could be able to adjust behavioral dysfunction, biochemical biomarkers and recovered cellular antioxidant level in depressed animals. The surprising results were achieved by raise in COQ₁₀ level, which could regulate the overexpression of the AMPK gene in stressful conditions. The regulatory effect of apigenin in inflammatory signaling pathways such as Nlrp3, and Tlr4 gene expression was studied at the surface part of the hippocampus.

Inhibition of α-glucosidase and α-amylase by herbal compounds for the treatment of type 2 diabetes: A validation of in silico reverse docking with in vitro enzyme assays

BACKGROUND

α-Amylase and α-glucosidase are important therapeutic targets for the management of type 2 diabetes mellitus. The inhibition of these enzymes decreases postprandial hyperglycemia. In the present study, compounds found in commercially available herbs and spices were tested for their ability to inhibit α-amylase and α-glucosidase. These compounds were acetyleugenol, apigenin, cinnamic acid, eriodictyol, myrcene, piperine, and rosmarinic acid.

METHODS

The enzyme inhibitory nature of the compounds was evaluated using in silico docking analysis with Maestro software and was further confirmed by in vitro α-amylase and α-glucosidase biochemical assays.

RESULTS

The relationships between the in silico and in vitro results were well correlated; a more negative docking score was associated with a higher in vitro inhibitory activity. There was no significant (P > .05) difference between the inhibition constant (K_i ) value of acarbose, a widely prescribed α-glucosidase and α-amylase inhibitor, and those of apigenin, eriodictyol, and piperine. For α-amylase, there was no significant (P > .05) difference between the K_i value of acarbose and those of apigenin, cinnamic acid, and rosmarinic acid. The effect of the herbal compounds on cell viability was assessed with the sulforhodamine B (SRB) assay in C2C12 and HepG2 cells. Acetyleugenol, cinnamic acid, myrcene, piperine, and rosmarinic acid had similar (P > .05) IC₅₀ values to acarbose.

CONCLUSIONS

Several of the herbal compounds studied could regulate postprandial hyperglycemia. Using herbal plants has several advantages including low cost, natural origin, and easy cultivation. These compounds can easily be consumed as teas or as herbs and spices to flavor food.

Protective mechanism of Erigeron breviscapus injection on blood-brain barrier injury induced by cerebral ischemia in rats

This study investigates the protective effect of Erigeron breviscapus injection, a classic traditional Chinese medicine most typically used by Chinese minority to treat stroke, on cerebral ischemia-reperfusion injury and the related signaling pathways. Use network pharmacology methods to study the relationship between E. breviscapus (Vant.) Hand-Mazz. and ischemic stroke, predict the mechanism and active ingredients of E. breviscapus (Vant.) Hand-Mazz. in improving ischemic stroke disease. We study the protective effect of E. breviscapus injection on blood-brain barrier (BBB) injuries induced by cerebral ischemia in rats by regulating the ROS/RNS-MMPs-TJs signaling pathway. The rat model of focal cerebral ischemia-reperfusion injury has been prepared using the wire-suppository method. Firstly, the efficacy of E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid in protecting BBB injury caused by cerebral ischemia has been evaluated. Secondly, the following two methods have been used to study the mechanism of E. breviscapus injection in regulating the ROS/RNS-MMPS-TJS signaling pathway: real-time PCR and western blot for the determination of iNOS, MMP-9, claudin-5, occludin, ZO-1 mRNA and protein expression in brain tissue. We find that PI3K-Akt signaling pathway predicted by network pharmaology affects the blood-brain barrier function, so we chose the blood-brain barrier-related MMP-9, claudin-5, iNOS, occludin and ZO-1 proteins are used for research. The results of our research show that 3 drugs can reduce the rate of cerebral infarction in rats, relieve the abnormal neuroethology of rats, reduce the degree of brain tissue lesion, increase the number of the Nissl corpuscle cells and repair the neuron ultrastructure in injured rats. At the same time, it can obviously reduce the ultrastructure damage of the BBB in rats. All three drugs significantly reduced the content of Evans blue in the ischemic brain tissue caused by cerebral ischemia in rats with BBB injury. In addition, E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid can decrease the protein expression of iNOS and MMP-9 in rat ischemic brain tissue. In addition, 3,5-dicaffeoylquinic acid can increase the protein expression of claudin-5. We conclude that E. breviscapus injection, Scutellarin and 3,5-dicaffeoylquinic acid have obvious therapeutic effects on BBB and neuron injury induced by cerebral ischemia in rats. Our results from studying the mechanism of action show that E. breviscapus injection and Scutellarin inhibited the activation of MMP-9 by inhibiting the synthesis of iNOS, 3,5-dicaffeoylquinic acid inhibits the expression and activation of MMP-9 by inhibiting the activation of iNOS and reducing the generation of free radicals, thus reducing the degradation of important cytoskeleton connexin claudin-5 in the tight junction (TJ) structure by inhibiting the expression and activation of MMP-9. Finally BBB structure integrity was protected.

Protective effect of flavonoids from Passiflora edulis Sims on diabetic complications in rats

OBJECTIVES

This study was carried out to evaluate the effects of flavonoids present in leaves of Passiflora edulis fruit on complications induced by diabetes in rats.

METHODS

The extract of P. edulis leaf was obtained by 70% ethanol maceration. From the dry extract, the fractions were obtained by consecutive liquid-liquid partition with hexane, ethyl acetate and n-butanol. The content of isoorientin of ethyl acetate and n-butanol fractions was determined by ultra-performance liquid chromatography coupled with electrospray and triple quadrupole ionization (TQD) analysis in tandem mass spectrometry (UPLC-ESI-Tq-MS). Only Fr-BuOH was used to treat diabetic or not Wistar rats. Biochemical parameters, platelet aggregation and production of reactive species were evaluated.

KEY FINDINGS

The UPLC-ESI-Tq-MS analysis revealed the presence of several flavonoids, among which we identified five possible flavonoids c-heterosides (luteolin-7-O-pyranosyl-3-O-glucoside, apigenin-6-8-di-C-glycoside, apigenin-6-C-arabinoside-8-C-glycoside, isoorientin, isovitexin). The diabetic rats (treated intraperitoneally with alloxan, 150 mg/kg) treated with Fr-BuOH (20 mg/kg/day for 90 days) presented improvement in blood glucose, serum levels of fructosamine, lipid profile and urea. Furthermore, the Fr-BuOH reduced both platelet aggregation and the production of oxidant species in diabetic animals.

CONCLUSIONS

These results suggested that flavonoid C-glycosides present in the Fr-BuOH may be beneficial for the diabetic state, preventing complications induced by diabetes.

Apigenin exerts chemopreventive effects on lung injury induced by SiO2 nanoparticles through the activation of Nrf2

Apigenin (APG) is a flavonoid widely distributed in fruits, vegetables, and herbs, with comprehensive pharmacological effects. In this paper, we report that APG can elicit a protective effect, which is comparable to those induced by gymnoside II/n-BuOH extracts of Bletilla striata, on SiO₂-induced lung injury in vitro and in vivo. In vitro experiments showed that APG (25 μM) could restore the SiO₂-decreased A549 cell viability and lower the apoptotic rate and the production of intracellular reactive oxygen species (ROS) in A549 cells treated with nm SiO₂. Western blot results showed that APG (25 μM) could increase the level of Nuclear factor E2-related factor 2 (Nrf2) and its downstream proteins. In vivo experiments showed that APG (20 mg/kg) could potently alleviate the SiO₂-elicited lung injury by enhancing the Nrf2 expression and thereby suppressing Bax/Bcl-2 pathway. The present study suggests that APG can significantly alleviate the SiO₂-induced lung injury both in vitro and in vivo through, at least partially, activating Nrf2 expression.

Isovitexin potentiated the antitumor activity of cisplatin by inhibiting the glucose metabolism of lung cancer cells and reduced cisplatin-induced immunotoxicity in mice

The increased resistance and toxicity have become the main causes of chemotherapy failure for treating lung cancer. The combination of chemotherapeutic drugs with other agents has been recognized as a promising strategy to overcome these difficulties. Isovitexin (IVT) is a well-known flavone C-glycoside found in many plants and has attracted wide attention due to its obvious antitumor and antioxidant effects. In this study, we investigated the synergistic effects of IVX and cisplatin (DDP) in non-small cell lung cancer (NSCLC) A549 and H1975 cells. The results showed that the combined treatment with IVT and DDP markedly inhibited proliferation and induced apoptosis of the two NSCLC cells. Using a mouse model of A549 xenograft, IVT potentiated the inhibition of DDP on tumor growth, but reduced DDP-induced hepatotoxicity and nephrotoxicity in mice. Remarkedly, IVT promoted lipopolysaccharide (LPS)- and lectin- stimulated splenocyte proliferation, and enhance cytotoxic T lymphocyte (CTL) and natural killer (NK) cell activities as well as the production of IL-2 and TNF-α. Furthermore, IVT significantly reduced glucose uptake, lactate production, and ATP production, and downregulated the protein expressions of pyruvate kinase M2 (PKM2)-mediated pathway in both A549 and H1975 cells. After the over-expression of PKM2 in the NSCLC cells, the synergistic antitumor effect of IVT and DDP was markedly weakened. Therefore, IVT not only inhibited cell proliferation and glucose metabolism via downregulating the expression of PKM2 to enhance the antitumor activity of DDP against lung cancer cells, and improved DDP-induced immunotoxicity in mice. It also presented a novel strategy to enhance the anti-tumor effect of platinum-based chemotherapy against NSCLC.

Multitargeted Effects of Vitexin and Isovitexin on Diabetes Mellitus and Its Complications

BACKGROUND

Till date, there is no known antidote to cure diabetes mellitus despite the discovery and development of diverse pharmacotherapeutic agents many years ago. Technological advancement in natural product chemistry has led to the isolation of analogs of vitexin and isovitexin found in diverse bioresources. These compounds have been extensively studied to explore their pharmacological relevance in diabetes mellitus. Aim of the Study. The present review was to compile results from in vitro and in vivo studies performed with vitexin and isovitexin derivatives relating to diabetes mellitus and its complications. A systematic online literature query was executed to collect all relevant articles published up to March 2020.

RESULTS

In this piece, we have collected data and presented it in a one-stop document to support the multitargeted mechanistic actions of vitexin and isovitexin in controlling diabetes mellitus and its complications.

CONCLUSION

Data collected hint that vitexin and isovitexin work by targeting diverse pathophysiological and metabolic pathways and molecular drug points involved in the clinical manifestations of diabetes mellitus. This is expected to provide a deeper understanding of its actions and also serve as a catapult for clinical trials and application research.

Apigenin promotes osteogenic differentiation of mesenchymal stem cells and accelerates bone fracture healing via activating Wnt/β-catenin signaling

Apigenin (API), a natural plant flavone, is abundantly found in common fruits and vegetables. As a bioactive flavonoid, API exhibits several activities including antiproliferation and anti-inflammation. A recent study showed that API could retard osteoporosis progress, indicating its role in the skeletal system. However, the detailed function and mechanism remain obscure. In the present study, API was found to promote osteogenic differentiation of mesenchymal stem cells (MSCs). And further investigation showed that API could enhance the expression of the critical transcription factor β-catenin and several downstream target genes of Wnt signaling, thus activated Wnt/β-catenin signaling. Using a rat femoral fracture model, API was found to improve new bone formation and accelerate fracture healing in vivo. In conclusion, our data demonstrated that API could promote osteogenesis in vitro and facilitate the fracture healing in vivo via activating Wnt/β-catenin signaling, indicating that API may be a promising therapeutic candidate for bone fracture repair.NEW & NOTEWORTHY1) API promoted osteogenic differentiation of human MSCs in vitro; 2) API facilitated bone formation and accelerated fracture healing in vivo; 3) API stimulated Wnt/β-catenin signaling during osteogenesis of human MSCs.

Protective effects of apigenin on altered lipid peroxidation, inflammation, and antioxidant factors in methotrexate-induced hepatotoxicity

Methotrexate (MTX) is used as an effective chemotherapeutic agent against autoimmune diseases and tumors. Oxidative stress and inflammation are involved in the pathogenesis of MTX-induced damage. This study aimed at examining the ameliorating effects of apigenin (API) as a natural antioxidant on MTX-induced hepatotoxicity. The rats were classified into four groups: group I: normal saline-treated, group II: MTX-treated (20 mg/kg, ip, single dose at day 7), group III: MTX + API-treated (20 mg/kg, po), and group IV: API-treated. API was administrated for 9 days. Alanine aminotransferase (ALT), alkaline phosphatase (ALP), and aspartate aminotransferase (AST) were used as biochemical factors of MTX-induced hepatic injury. In hepatic tissues, the levels of malondialdehyde (MDA), nitric oxide (NO), glutathione (GSH), and activities of antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) as oxidative stress markers along with inflammatory factors such as tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL-1β) were assessed. Our results showed that MTX administration significantly increased ALP, ASP, ALT, MDA, NO, TNF-α, and IL-1β levels and significantly decreased antioxidant factors such as GSH, CAT, GPx, and SOD. The API pretreatment group showed a significant rise in hepatic antioxidant markers, besides significant reductions in the serum levels of AST, ALT, and ALP and hepatic content of MDA, TNF-α, NO, and IL-1β. In addition, the hepatoprotective effect of API was confirmed by histological evaluation of the liver. API can prevent MTX-induced hepatotoxicity through mitigation of oxidative stress and inflammation.

Apigenin ameliorates doxorubicin-induced renal injury via inhibition of oxidative stress and inflammation

BACKGROUND AND OBJECTIVE

Doxorubicin (DOX) is an anthracycline antitumor antibiotic widely utilized in treating various tumors. Nevertheless, the toxicity of DOX toward normal cells limits its applicability, with nephrotoxicity considered a major dose-limiting adverse effect. Apigenin (APG), a flavonoid widely distributed in natural plants, has been reported to have antioxidant, anti-inflammatory, and mild tumor-suppressive properties. In this study, we investigated the role of APG in DOX-induced nephrotoxicity and chemotherapeutic efficacy.

METHODS

Male BALB/c mice were administered DOX (11.5 mg/kg) via the tail vein to establish the DOX nephropathy model. After treatment with or without APG (125, 250, and 500 mg/kg) for two weeks, urine, serum, and tissue samples were collected to evaluate proteinuria, serum albumin, serum creatinine (Scr), blood urea nitrogen (BUN), superoxide dismutase (SOD) activity, malondialdehyde (MDA), glutathione (GSH), and pathological changes. Rat renal tubular epithelial cells (NRK52E), murine podocyte cells (MPC5), and murine breast cancer cells (4T1) were utilized to verify the effect of APG on DOX-induced cell injury. An MTT assay was employed to analyze cell viability. Apoptosis was evaluated using a colorimetric TUNEL staining and cleaved caspase-3 protein analysis by western blotting. A reactive oxygen species (ROS)/superoxide (O₂-) fluorescence probe was employed to determine oxidative injury. Western blotting was used to analyze nephrin, α-smooth muscle actin (α-SMA), collagen I (Col1), fibronectin (FN), and SOD2 expression. The mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-18 (IL-18), IL-6, NACHT, LRR, PYD domain-containing protein 3 (NLRP3), caspase-1, and IL-1β were tested by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

APG ameliorated DOX-elicited renal injuries in both the glomeruli and tubules. The DOX + APG groups had much lower tissue MDA, IL-6, TNF-α, NLRP3, caspase-1, and IL-1β levels and generation of intracellular ROS, but significantly higher SOD activity and GSH levels compared to those of the DOX group. Additionally, APG attenuated DOX-induced morphological changes, loss of cellular viability, and apoptosis in NRK-52E and MPC-5 cells, but not in 4T1 cells.

CONCLUSION

APG has a protective role against DOX-induced nephrotoxicity, without weakening DOX cytotoxicity in malignant tumors. Thus, APG may serve as a potential protective agent against renal injury and inflammatory diseases and may be a promising candidate to attenuate renal toxicity in cancer patients treated with DOX.

Scutellarin Inhibits the Growth and EMT of Gastric Cancer Cells through Regulating PTEN/PI3K Pathway

Gastric cancer is one of the most common malignancies with a high mortality rate world. This study intends to make clear the role and mechanism of the Scutellarin (Scu), a flavonoid isolated from Erigeron breviscapus (Vant.) Hand.-Mazz, in regulating the evolvement of gastric cancer. We selected different doses of Scu to treat gastric cancer cells (MGC-803 and AGS). Then, cell counting kit-8 (CCK8) assay was conducted to verify the proliferation of tumor cells, while flow cytometry was adopted to test the apoptosis rate. Meanwhile, Western blot was conducted to examine epithelial-mesenchymal transition (EMT) markers and the expression of phosphatase and tensin homolog (PTEN)/phosphatidylinositol 3-kinase (PI3K) and apoptosis-related proteins (Bax, Bcl2 and Caspase3). Moreover, xenograft tumor experiment in nude mice was established to verify the effect of Scu on tumor growth. Furthermore, the knockdown model of PTEN was constructed, and the influence of PTEN on the anti-tumor effect of Scu was investigated. As a result, Scu inhibited cell proliferation, EMT and promoted the apoptosis in gastric cancer dose-dependently. Additionally, Scu attenuated tumor cell growth in vivo. Besides, Scu enhanced the expression of PTEN while reduced the phosphorylated level of PI3K. Moreover, the mechanistic study proved that Scu inactivated PI3K by up-regulating PTEN, thus dampening tumor progression. In conclusion, Scu dampened the growth and EMT of gastric cancer by regulating the PTEN/PI3K pathway.

Therapeutic potentials of the natural plant flavonoid apigenin in polycystic ovary syndrome in rat model: via modulation of pro-inflammatory cytokines and antioxidant activity

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age, which is associated with increased androgens, chronic inflammation, and oxidative stress. Current research aims at determining the effect of flavonoid apigenin on the level of antioxidant and anti-inflammatory factors in ovarian tissue of rats with PCOS. In this study, 32 female Wistar rats were divided into four groups (n = 8): control, PCOS control, and treated groups (20 and 40 mg/kg apigenin). After 21 days of intervention, the serum levels of sex hormones and gonadotropins were measured. The ovarian tissue was removed for biochemical and histological studies. Research findings indicated that apigenin causes significant decrease in estrogen, testosterone levels, LH and LH to FSH ratio, and significant increase in progesterone and FSH levels in serum of treated groups compared to PCOS control group. Different doses of apigenin significantly decreased the inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and total oxidative status (TOS). The total antioxidant capacity (TAC) and superoxide dismutase (SOD) activity significantly increased in treated groups compared to the PCOS control group. The histological results indicated that the number of cysts and theca layer thickness significantly decreased and the number of corpora lutea and granulosa layer thickness significantly increased in the rats receiving the apigenin as compared to the PCOS control group. Flavonoid apigenin through antioxidant and anti-inflammatory properties can be used as an alternative method for treating patients with PCOS.

Scutellarin inhibits the invasive potential of malignant melanoma cells through the suppression epithelial-mesenchymal transition and angiogenesis via the PI3K/Akt/mTOR signaling pathway

Malignant melanoma is the leading cause of death from skin disease, due in large part to its propensity to metastasize. Scutellarin is an active flavone extracted from traditional Chinese herb Erigeron breviscapus (Vant.) Hand. Mazz. Recent studies have reported that scutellarin can be utilized to treat various types of tumors. In this study, we investigated the effects of scutellarin on melanoma cancer cell invasive potential and the molecular mechanisms underlying these effects using A375 melanoma cells lines. The in-vitro antitumor activity of scutellarin was evaluated by CCK-8 assay, wound-healing assay, transwell assays, adhesion assays, and tube formation assays to assess the cell viability, migration, invasion, adhesion, and angiogenesis, respectively. Also, western blotting assay was used to assess the level of PI3K/Akt/mTOR signaling pathway proteins in A375 cells. We found that scutellarin significantly inhibited melanoma cell lines and HUVECs viability in a time- and concentration-dependent manners. Additionally, scutellarin effectively suppressed tumor cell migration, invasion, adhesion through the suppression of EMT and angiogenesis by inhibiting the PI3K/Akt/mTOR signaling pathway. These results indicated that scutellarin could markedly inhibit the invasive potential of melanoma cell lines by suppressing the EMT and angiogenesis through the PI3K/Akt/mTOR signaling pathway. It suggests that scutellarin might be a potential compound in malignant melanoma treatment.

Antitumor and Anti-Invasive Effect of Apigenin on Human Breast Carcinoma through Suppression of IL-6 Expression

Interleukin (IL)-6 plays a crucial role in the progression, invasion, and metastasis of breast cancer. Triple-negative breast cancer (TNBC) cell line MDA-MB-231 is known for its aggressive metastasis. Epithelial to mesenchymal transition (EMT) is a critical process in cancer metastasis. The positive correlation between IL-6 and EMT in tumor microenvironment is reported. We found significantly upregulated IL-6 expression in MDA-MB-231 cells. A blockade of IL-6 expression decreased levels of phosphorylated signal transducer and activator of transcription 3 (pSTAT3), phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), phosphorylated protein kinase B (pAkt), and cell cycle-related molecules, including cyclin-dependent kinases (CDKs) and cyclins in MDA-MB-231 cells. A short-hairpin RNA (shRNA)-mediated blockade of IL-6 expression inhibited migration and N-cadherin expression and induced E-cadherin expression in MDA-MB-231 cells. Growth rate was slower for the tumors derived from IL-6 shRNA-treated MDA-MB-231 cells than for those derived from control shRNA-treated MDA-MB-231 cells. The expression of pSTAT3, phosphorylated extracellular signal-regulated kinase (pERK), PI3K, pAkt, snail, vimentin, and N-cadherin was significantly lower in tumors from IL-6 shRNA-treated MDA-MB cells. In addition, apigenin treatment significantly inhibited the growth of MDA-MB-231-derived xenograft tumors along with the protein expressions of pSTAT3, pERK, IL-6, PI3K, pAkt, and N-cadherin. Our results demonstrate that the anti-invasive effect of apigenin in MDA-MB-231-derived xenograft tumors is mediated by the inhibition of IL-6-linked downstream signaling pathway.

A NMR-Based Metabonomics Approach to Determine Protective Effect of a Combination of Multiple Components Derived from Naodesheng on Ischemic Stroke Rats

Naodesheng (NDS) is a widely used traditional Chinese medicine (TCM) prescription for the treatment of ischemic stroke. A combination of 10 components is derived from NDS. They are: Notoginsenoside R1, ginsenoside Rg1, ginsenoside b1, ginsenoside Rd, hydroxysafflor yellow A, senkyunolide I, puerarin, daidzein, vitexin, and ferulic acid. This study aimed to investigate the protective effect of the ten-component combination derived from NDS (TCNDS) on ischemic stroke rats with a middle cerebral artery occlusion (MCAO) model by integrating an NMR-based metabonomics approach with biochemical assessment. Our results showed that TCNDS could improve neurobehavioral function, decrease the cerebral infarct area, and ameliorate pathological features in MCAO model rats. In addition, TCNDS was found to decrease plasma lactate dehydrogenase (LDH) and malondialdehyde (MDA) production and increase plasma superoxide dismutase (SOD) production. Furthermore, ¹H-NMR metabonomic analysis indicated that TCNDS could regulate the disturbed metabolites in the plasma, urine, and brain tissue of MCAO rats, and the possible mechanisms were involved oxidative stress, energy metabolism, lipid metabolism, amino acid metabolism, and inflammation. Correlation analysis were then performed to further confirm the metabolites involved in oxidative stress. Correlation analysis showed that six plasma metabolites had high correlations with plasma LDH, MDA, and SOD. This study provides evidence that an NMR-based metabonomics approach integrated with biochemical assessment can help to better understand the underlying mechanisms as well as the holistic effect of multiple compounds from TCM.

Apigenin Inhibits IL-31 Cytokine in Human Mast Cell and Mouse Skin Tissues

IL-31 is a recently discovered cytokine that is produced not only in T-cells but also in mast cells. It is strongly implicated to play a key role in inflammatory diseases and in the pathogenesis of itch in atopic dermatitis. Apigenin, a flavonoid of plant origin has numerous biological applications. In this study, we showed that apigenin modulates IL-31 mRNA, protein expression, and release in stimulated human mast (HMC-1) by inhibiting the phosphorylation activation of MAPK and NF-κB. To determine whether apigenin has similar effects in vivo, using Compound 48/80, we developed an atopic dermatitis itch model in mice and found an increase in IL-31 expression in the skin. We also revealed that apigenin prevents the infiltration and degranulation of mast cells and suppressed mRNA and protein expression of IL-31 in the skin of mice. These results provide a new suggestion of the potential applicability of apigenin for treatment of various inflammatory diseases and itch mediated by IL-31.

The Therapeutic Potential of Apigenin

Several plant bioactive compounds have exhibited functional activities that suggest they could play a remarkable role in preventing a wide range of chronic diseases. The largest group of naturally-occurring polyphenols are the flavonoids, including apigenin. The present work is an updated overview of apigenin, focusing on its health-promoting effects/therapeutic functions and, in particular, results of in vivo research. In addition to an introduction to its chemistry, nutraceutical features have also been described. The main key findings from in vivo research, including animal models and human studies, are summarized. The beneficial indications are reported and discussed in detail, including effects in diabetes, amnesia and Alzheimer's disease, depression and insomnia, cancer, etc. Finally, data on flavonoids from the main public databases are gathered to highlight the apigenin's key role in dietary assessment and in the evaluation of a formulated diet, to determine exposure and to investigate its health effects in vivo.

Scutellarin Prevents Angiogenesis in Diabetic Retinopathy by Downregulating VEGF/ERK/FAK/Src Pathway Signaling

BACKGROUND

Diabetic retinopathy (DR) is a serious microvascular complication of diabetes. This study demonstrates the antiangiogenic effects of scutellarin (SCU) on high glucose- and hypoxia-stimulated human retinal endothelial cells (HRECs) and on a diabetic rat model by oral administration. The antiangiogenic mechanisms of SCU in vitro and in vivo were investigated.

METHOD

HRECs were cultured in high glucose- (30 mM D-glucose) and hypoxia (cobalt chloride-treated)-stimulated diabetic condition to evaluate the antiangiogenic effects of SCU by CCK-8 test, cell migration experiment (wound healing and transwell), and tube formation experiment. A streptozotocin-induced type II diabetic rat model was established to measure the effects of oral administration of SCU on protecting retinal microvascular dysfunction by Doppler waveforms and HE staining. We further used western blot, luciferase reporter assay, and immunofluorescence staining to study the antiangiogenic mechanism of SCU. The protein levels of phospho-ERK, phospho-FAK, phospho-Src, VEGF, and PEDF were examined in HRECs and retina of diabetic rats.

RESULT

Our results indicated that SCU attenuated diabetes-induced HREC proliferation, migration, and tube formation and decreased neovascularization and resistive index in the retina of diabetic rats by oral administration. SCU suppressed the crosstalk of phospho-ERK, phospho-FAK, phospho-Src, and VEGF in vivo and in vitro.

CONCLUSIONS

These results suggested that SCU can be an oral drug to alleviate microvascular dysfunction of DR and exerts its antiangiogenic effects by inhibiting the expression of the crosstalk of VEGF, p-ERK, p-FAK, and p-Src.

Apigenin reverses lung injury and immunotoxicity in paraquat-treated mice

Paraquat (PQ) induces acute lung injury (ALI) and immunotoxicity. Apigenin exerts anti-oxidant and anti-inflammatory properties. The purpose of this study was to investigate the possible protective effects of apigenin on PQ-induced ALI and immunotoxicity in mice. Female C57BL/6 mice received a single injection of PQ (50 mg/kg). Apigenin was given for 7 consecutive days starting 5 days before PQ exposure. The toxicity markers were evaluated in terms of weight loss, lung histopathology, oxidative stress, inflammation, and T cell functions after PQ exposure. Poisoned mice exhibited severe lung tissue lesions, inflammatory cell infiltration and the release of pro-inflammatory cytokines IL-6 and TNF-α. PQ administration increased the lung wet/dry ratios and lipid peroxidation by the increase of MDA levels and decreased anti-oxidase activity including SOD, GSH-PX, and CAT. While such effect on lung was reversed by apigenin. Importantly, PQ-induced immunotoxicity was also observed in a decrease of spleen weight, inhibition of T cell proliferation and T-cell secreting IL-2 from splenocytes. Further mechanism analysis found that PQ administration could decrease total splenocytes, CD4⁺ and CD8⁺ T cells, SOD, GSH-PX, and CAT activity, and increased the levels of MDA and the concentrations of pro-inflammatory cytokines IL-6 and TNF-α compared to control mice. However, apigenin treatment reversed PQ-induced immunotoxicity. In summary, all results suggest that apigenin has beneficial effects on PQ-induced ALI and immunotoxicity possibly, and it could be related, at least in part, to its ability in modulating inflammation and oxidative stress, although in-depth studies might be needed to fully understand the mechanism of action.

Efficacy of Apigenin and Miltefosine Combination Therapy against Experimental Cutaneous Leishmaniasis

Leishmaniasis is a neglected tropical disease caused by several different species of Leishmania. Treatment of leishmaniasis involves a limited drug arsenal that is associated with severe side effects, high costs, and drug resistance. Therefore, combination therapy has emerged as a strategy to improve leishmaniasis treatment. Here, we report the interaction of miltefosine and apigenin in vitro and in vivo. Combination therapy using low doses of these two drugs results in good clinical and parasitological responses.

Apigenin sensitizes hepatocellular carcinoma cells to doxorubic through regulating miR-520b/ATG7 axis

Chemo-resistance is a serious obstacle for successful treatment of cancer. Apigenin, a dietary flavonoid, has been reported as an anticancer drug in various malignant cancers. This study aimed to investigate the potential chemo-sensitization effect of apigenin in doxorubicin-resistant hepatocellular carcinoma cell line BEL-7402/ADM. We observed that apigenin significantly enhanced doxorubicin sensitivity, induced miR-520b expression and inhibited ATG7-dependent autophagy in BEL-7402/ADM cells. In addition, we also showed that miR-520b mimics increased doxorubicin sensitivity and inhibited ATG7-dependent autophagy. Meanwhile, we indicated that ATG7 was a potential target of miR-520b. Furthermore, APG inhibited the growth of hepatocellar carcinoma xenografts in nude mice by up-regulating miR-520b and inhibiting ATG7. Our finding provides evidence that apigenin sensitizes BEL-7402/ADM cells to doxorubicin through miR-520b/ATG7 pathway, which furtherly supports apigenin as a potential chemo-sensitizer for hepatocellular carcinoma.