Apigenin-7-glucoside-loaded nanoparticle alleviates intestinal ischemia-reperfusion by ATF3/SLC7A11-mediated ferroptosis.

Intestinal ischemia reperfusion injury (II/R injury) is a common and intractable pathophysiological process in critical patients, for which exploring new treatments and mechanisms is of great importance to improve treatment outcomes. Apigenin-7-O-Glucoside (AGL) is a sugar derivative of apigenin natural product with various pharmacological activities to protect against intestinal diseases. In this study, we synthesized two amphiphilic molecules, namely DTPA-N10-10 and mPEG-TK-DA, which can scavenge free radicals and reactive oxygen species (ROS). They were successfully encapsulated AGL through self-assembly, resulting in the formation of multi-site ROS scavenging nanoparticles called PDN@AGL. In vitro and in vivo experiments demonstrated that PDN@AGL could protect intestinal tissues by reducing lipid peroxidation, lowering ROS levels and inhibiting ferroptosis during II/R injury. Furthermore, our study revealed, for the first time, that the regulation of the ATF3/SLC7A11 pathway by PDN@AGL may play a crucial role in mitigating II/R injury. In conclusion, our study confirmed the beneficial effects of PDN@AGL in combating II/R injury through the ATF3/SLC7A11-mediated regulation of ferroptosis and oxidative stress. These findings lay the groundwork for the potential application of PDN@AGL in the treatment of II/R injury.

The CDK1/TFCP2L1/ID2 cascade offers a novel combination therapy strategy in a preclinical model of bladder cancer.

Aberrant activation of embryogenesis-related molecular programs in urothelial bladder cancer (BC) is associated with stemness features related to oncogenic dedifferentiation and tumor metastasis. Recently, we reported that overexpression of transcription factor CP2-like protein-1 (TFCP2L1) and its phosphorylation at Thr177 by cyclin-dependent kinase-1 (CDK1) play key roles in regulating bladder carcinogenesis. However, the clinical relevance and therapeutic potential of this novel CDK1-TFCP2L1 molecular network remain elusive. Here, we demonstrated that inhibitor of DNA binding-2 (ID2) functions as a crucial mediator by acting as a direct repressive target of TFCP2L1 to modulate the stemness features and survival of BC cells. Low ID2 and high CDK1 expression were significantly associated with unfavorable clinical characteristics. TFCP2L1 downregulated ID2 by directly binding to its promoter region. Consistent with these findings, ectopic expression of ID2 or treatment with apigenin, a chemical activator of ID2, triggered apoptosis and impaired the proliferation, suppressed the stemness features, and reduced the invasive capacity of BC cells. Combination treatment with the specific CDK1 inhibitor RO-3306 and apigenin significantly suppressed tumor growth in an orthotopic BC xenograft animal model. This study demonstrates the biological role and clinical utility of ID2 as a direct target of the CDK1-TFCP2L1 pathway for modulating the stemness features of BC cells.

Screening of bioactive ingredients of Tsantan Sumtang in ameliorating H9c2 cells injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Tsantan Sumtang (TS), a traditional Tibetan medicine, has been used in the clinic for the treatment of myocardial ischemia (MI) for ages, however, the bioactive ingredients that are responsible for improving MI remain unknown. AIM OF THE STUDY: This study investigated the chemical components of TS and their medicinal efficacies at cell levels, in order to expound the bioactive ingredients in TS. MATERIALS AND METHODS: First, a response-surface methodology was employed to determine the optimum ethanol reflux extraction process of polyphenols in TS (PTS) due to their close correlation with MI improvement. Second, a serum pharmacochemistry technique was used to analyze the compounds of PTS absorbed into the blood of rats. Third, hypoxia-, H2O2-, and adriamycin (ADM)-induced H9c2 cell injury models were used to investigate the cardioprotective effects of these compounds in vitro. Fourth, protective effects of isovitexin, quercitrin, and isoeugenol on mitochondrial function were further tested. RESULTS: The optimum extraction conditions for obtaining PTS were an ethanol concentration of 78.22%, an extraction time of 67.4 min, and a material-liquid ratio of 1:72.60 mL/g. Serum pharmacochemistry analysis detected 21 compounds, of which 11 compounds were always present in the blood within 5 h. Cytotoxicity and the protective effect of 11 compounds in hypoxia-, H2O2-, and ADM-induced H9c2 cell injury models shown that isovitexin, quercitrin, and isoeugenol had almost no cytotoxicity, and they could elevate the survival rate in injured H9c2 cells. Furthermore, isovitexin, quercitrin, and isoeugenol could decrease mitochondrial reactive oxygen species (ROS) releasion, inhibite mitochondrial permeability transition pore (mPTP) opening, ameliorate the change of mitochondrial membrane potential (MMP) to exert mitochondrial protection effect. CONCLUSION: Isovitexin, quercitrin, and isoeugenol exhibited cardioprotective effect at cell levles, these three compounds might be the bioactive ingredients in TS. These findings elucidate the pharmacodynamic substances and mechanisms of TS, guiding its clinical use.

The Zebrafish Embryo as a Model to Test Protective Effects of Food Antioxidant Compounds.

The antioxidant activity of food compounds is one of the properties generating the most interest, due to its health benefits and correlation with the prevention of chronic disease. This activity is usually measured using in vitro assays, which cannot predict in vivo effects or mechanisms of action. The objective of this study was to evaluate the in vivo protective effects of six phenolic compounds (naringenin, apigenin, rutin, oleuropein, chlorogenic acid, and curcumin) and three carotenoids (lycopene B, ß-carotene, and astaxanthin) naturally present in foods using a zebrafish embryo model. The zebrafish embryo was pretreated with each of the nine antioxidant compounds and then exposed to tert-butyl hydroperoxide (tBOOH), a known inducer of oxidative stress in zebrafish. Significant differences were determined by comparing the concentration-response of the tBOOH induced lethality and dysmorphogenesis against the pretreated embryos with the antioxidant compounds. A protective effect of each compound, except ß-carotene, against oxidative-stress-induced lethality was found. Furthermore, apigenin, rutin, and curcumin also showed protective effects against dysmorphogenesis. On the other hand, ß-carotene exhibited increased lethality and dysmorphogenesis compared to the tBOOH treatment alone.

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.

Triglyceride-mimetic prodrugs of scutellarin enhance oral bioavailability by promoting intestinal lymphatic transport and avoiding first-pass metabolism.

The intestinal capillary pathway is the most common way to absorb oral drugs, but for drugs with poor solubility and permeability and high first-pass metabolism, this pathway is very inefficient. Although intestinal lymphatic transport of lipophilic drugs or prodrugs is a promising strategy to improve the oral delivery efficiency of these drugs. The prodrug strategy for modifying compounds with Log P > 5 to promote intestinal lymphatic transport is a common approach. However, transport of poor liposoluble compounds (Log P < 0) through intestinal lymph has not been reported. Herein, triglyceride-mimetic prodrugs of scutellarin were designed and synthesized to promote intestinal lymphatic transport and increase oral bioavailability. Lymphatic transport and pharmacokinetic experiments showed that two prodrugs did promote intestinal lymphatic transport of scutellarin and the relative oral bioavailability was 2.24- and 2.45-fold of scutellarin, respectively. In summary, triglyceride-mimetic prodrugs strategy was used for the first time to study intestinal lymphatic transport of scutellarin with Log P < 0, which could further broaden the application range of drugs to improve oral bioavailability with the assistance of intestinal lymphatic transport.

Prophylactic effect of myricetin and apigenin against lipopolysaccharide-induced acute liver injury.

BACKGROUND: Liver has an important role in the initiation and progression of multiple organ failure that occurs in sepsis. Many natural active substances can be used to reduce the liver injury caused by sepsis. For this aim, the effects of myricetin and apigenin on mice model of acute liver injury was evaluated in this study. METHODS AND RESULTS: Thirty-six mice were randomly divided into six groups as; control, lipopolysaccharide (LPS) (5 mg/kg), LPS + myricetin (100 mg/kg), LPS + myricetin (200 mg/kg), LPS + apigenin (100 mg/kg), and LPS + apigenin (200 mg/kg) groups. Myricetin and apigenin were administered orally for 7 days, and LPS was administered intraperitoneally only on the 7th day of the study. 24 h after LPS application, all animals were sacrificed and serum biochemical parameters, histopathology and oxidative stress and inflammation markers of liver tissue were examined. Myricetin and apigenin pre-treatments increased serum albumin and total protein levels, liver GSH level and catalase and SOD activities and decreased serum ALT, AST, ALP, γ-GT, CRP, total and direct bilirubin levels, liver MPO activity, MDA, NOx, PGE2, TNF-α, IL-1ß, and IL-6 levels, iNOS and COX-2 mRNA levels, phosphorylation of NF-κB p65, IκB, and IKK proteins but not p38, ERK, and JNK proteins in LPS-treated mice. Myricetin and apigenin administration also regained the hepatic architecture disrupted during LPS application. CONCLUSION: Myricetin and apigenin pre-treatments led to reduction of liver injury indices and oxidative stress and inflammatory events and these flavonoids has probably hepatoprotective effects in acute liver injury.

A study on distribution and stability of drugs at the interface of a scutellarin-loaded emulsion.

This work mainly studies the interfacial behaviors of scutellarin on a newly developed emulsion and establishes a three-phase distribution model. The results showed that the concentration of scutellarin could decrease the interfacial tension and the gel-liquid crystal phase transition temperature of phospholipids. By observing the micromorphology of the emulsion, it is inferred that the drug exists on the emulsion interface. The distribution of drugs in three phases at different pH was calculated. The results showed that when pH was in the range of 3.0-8.0, the content of scutellarin in the oil phase was less than 0.25%; when pH < 7.4, more than 88% of the drugs were on the interface; when pH > 7.4, the drugs were mainly distributed in the aqueous phase. Therefore, the behavior of emulsions (pH 6.0) in vitro and in vivo is mainly composed of the behavior of drugs on the interface. The study above can explain some properties of the emulsions after loading scutellarin. Including the decrease of particle size and stability constant Ke, the increase of zeta potential, and the decreased chemical stability after the pH value went higher.

Apigenin ameliorates hyperuricemic nephropathy by inhibiting URAT1 and GLUT9 and relieving renal fibrosis via the Wnt/ß-catenin pathway.

BACKGROUND: Hyperuricemia (HUA) is characterized by abnormal serum uric acid (UA) levels and demonstrated to be involved in renal injury leading to hyperuricemic nephropathy (HN). Apigenin (API), a flavonoid naturally present in tea, berries, fruits, and vegetables, exhibits various biological functions, such as antioxidant and anti-inflammatory activity. PURPOSE: To investigate the effect of API treatment in HN and to reveal its underlying mechanisms. METHODS: The mice with HN were induced by potassium oxonate intraperitoneally and orally administered for two weeks. The effects of API on renal function, inflammation, fibrosis, and uric acid (UA) metabolism in mice with HN were evaluated. The effects of API on urate transporters were further examined in vitro. RESULTS: The mice with HN exhibited abnormal renal urate excretion and renal dysfunction accompanied by increased renal inflammation and fibrosis. In contrast, API reduced the levels of serum UA, serum creatinine (CRE), blood urea nitrogen (BUN) and renal inflammatory factors in mice with HN. Besides, API ameliorated the renal fibrosis via Wnt/ß-catenin pathway suppression. Furthermore, API potently promoted urinary UA excretion and inhibited renal urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) in mice with HN. In vitro, API competitively inhibited URAT1 and GLUT9 in a dose-dependent manner, with IC50 values of 0.64 ± 0.14 µM and 2.63 ± 0.69 µM, respectively. CONCLUSIONS: API could effectively attenuate HN through co-inhibiting UA reabsorption and Wnt/ß-catenin pathway, and thus it might be a potential therapy to HN.

A natural flavonoid, apigenin isolated from Clerodendrum viscosum leaves, induces G2/M phase cell cycle arrest and apoptosis in MCF-7 cells through the regulation of p53 and caspase-cascade pathway

Background With 9.6 million deaths in 2018, cancer remains the second leading cause of death worldwide. Breast cancer is the most deadly type of cancer among females, with 55.2% of crude incidence rate and 16.6% of crude mortality rate. Purpose The present study was aimed to investigate the anti-breast cancer potential of natural dietary flavonoid, apigenin isolated from Clerodendrum viscosum leaves. Methods Apigenin was evaluated for in-depth anticancer activity in MCF-7 cells using cell viability assay, cell cycle analysis, Annexin-V-FLUOS staining, ROS induction, morphological analysis, and western blot analysis. Results Apigenin showed selective cytotoxicity on MCF-7 cells with an IC50-56.72 ± 2.35 µM, while negligible cytotoxicity was observed on WI-38 cells. Further, the flow cytometer-based analysis showed that apigenin halted MCF-7 cells in the G2/M phase arrest followed by dose-dependent apoptosis. Moreover, the FACS and confocal microscopy results confirmed the elevation of intracellular ROS and nuclear fragmentation in apigenin-treated MCF-7 cells. Western blots showed up-regulation of cell cycle regulatory proteins, increased p53 expression, Bax/Bcl-2 ratio, activation of caspases, and cleavage of PARP. Finally, apigenin treatment in the presence of Pifithrin-µ showed decreased apoptotic population and it was further confirmed through western blotting study. The results revealed the vital role of p53 in apigenin-induced apoptosis in MCF-7 cells. Conclusions In the present findings, treatment of apigenin-induced intracellular ROS in MCF-7 cells followed by induction of G2/M phase cell cycle arrest and further apoptosis through the regulation of p53 and caspase-cascade signaling pathway (AU)

Apigenin-Loaded PLGA-DMSA Nanoparticles: A Novel Strategy to Treat Melanoma Lung Metastasis.

The flavone apigenin (APG), alone as well as in combination with other chemotherapeutic agents, is known to exhibit potential anticancer effects in various tumors and inhibit growth and metastasis of melanoma. However, the potential of apigenin nanoparticles (APG-NPs) to prevent lung colonization of malignant melanoma has not been well investigated. APG-loaded PLGA-NPs were surface-functionalized with meso-2,3-dimercaptosuccinic acid (DMSA) for the treatment of melanoma lung metastasis. DMSA-conjugated APG-loaded NPs (DMSA-APG-NPs) administered by an oral route exhibited sustained APG release and showed considerable enhancement of plasma half-life, Cmax value, and bioavailability compared to APG-NPs both in plasma and the lungs. DMSA-conjugated APG-NPs showed comparably higher cellular internalization in B16F10 and A549 cell lines compared to that of plain NPs. Increased cytotoxicity was observed for DMSA-APG-NPs compared to APG-NPs in A549 cells. This difference between the two formulations was lower in B16F10 cells. Significant depolarization of mitochondrial transmembrane potential and an enhanced level of caspase activity were observed in B16F10 cells treated with DMSA-APG-NPs compared to APG-NPs as well. Western blot analysis of various proteins was performed to understand the mechanism of apoptosis as well as prevention of melanoma cell migration and invasion. DMSA conjugation substantially increased accumulation of DMSA-APG-NPs given by an intravenous route in the lungs compared to APG-NPs at 6 and 8 h. This was also corroborated by scintigraphic imaging studies with radiolabeled formulations administered by an intravenous route. Conjugation also allowed comparatively higher penetration as evident from an in vitro three-dimensional tumor spheroid model study. Finally, the potential therapeutic efficacy of the formulation was established in experimental B16F10 lung metastases, which suggested an improved bioavailability with enhanced antitumor and antimetastasis efficacy of DMSA-conjugated APG-NPs following oral administration.

Rapid Profiling and Identification of Vitexin Metabolites in Rat Urine, Plasma and Faeces after Oral Administration Using a UHPLC-Q-Exactive Orbitrap Mass Spectrometer Coupled with Multiple Data-mining Methods.

BACKGROUND: Vitexin is a natural flavonoid compound with multiple pharmacological activities and is extracted from the leaves and seeds of Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. However, the metabolite characterization of this component remains insufficient. OBJECTIVE: To establish a rapid profiling and identification method for vitexin metabolites in rat urine, plasma and faeces after oral administration using a UHPLC-Q-Exactive orbitrap mass spectrometer were coupled with multiple data-mining methods. METHODS: In this study a simple and rapid systematic strategy for the detection and identification of constituents was proposed based on UHPLC-Q-Exactive Orbitrap mass spectrometry in parallel reaction monitoring mode combining diagnostic fragment ion filtering techniques. RESULTS: A total of 49 metabolites were fully or partially characterized based on their accurate mass, characteristic fragment ions, retention times, corresponding ClogP values, and so on. It is obvious that C-glycosyl flavonoids often display an [M+H-120]+ ion that represents the loss of C4H8O4. As a result, these metabolites were presumed to be generated through glucuronidation, sulfation, deglucosylation, dehydrogenation, methylation, hydrogenation, hydroxylation, ring cleavage and their composite reactions. Moreover, the characteristic fragmentation pathways of flavonoids, chalcones and dihydrochalcones were summarized for the subsequent metabolite identification. CONCLUSION: The current study provided an overall metabolic profile of vitexin which will be of great help in predicting the in vivo pharmacokinetic profiles and understanding the action mechanism of this active ingredient.

Cytotoxicity of apigenin toward multiple myeloma cell lines and suppression of iNOS and COX-2 expression in STAT1-transfected HEK293 cells.

BACKGROUND: Apigenin is one of the most abundant dietary flavonoids that possesses multiple bio-functions. PURPOSE: This study was designed to determine the influence of apigenin on gene expressions, cancer cells, as well as STAT1/COX-2/iNOS pathway mediated inflammation and tumorigenesis in HEK293-STAT1 cells. Furthermore, the cytotoxic activity toward multiple myeloma (MM) cell lines was investigated. METHODS: Bioinformatic analyses were used to predict the sensitivity and resistance of tumor cells toward apigenin and to determine cellular pathways influenced by this compound. The cytotoxic and ferroptotic activity of apigenin was examined by the resazurin reduction assay. Additionally, we evaluated apoptosis, and cell cycle distribution, induction of reactive oxygen species (ROS) and loss of integrity of mitochondrial membrane (MMP) by using the flow cytometry analysis. DAPI staining was used to detect characteristic apoptotic features. Furthermore, we verified its anti-inflammatory and additional mechanism of cell death by western blotting. RESULTS: COMPARE and hierarchical cluster analyses exhibited that 29 of 55 tumor cell lines were sensitive against apigenin (p < 0.001). The Ingenuity Pathway Analysis data showed that important bio-functions affected by apigenin were: gene expression, cancer, hematological system development and function, inflammatory response, and cell cycle. The STAT1 transcription factor was chosen as target protein on the basis of gene promoter binding motif analyses. Apigenin blocked cell proliferation of wild-type HEK293 and STAT1 reporter cells (HEK293-STAT1), promoted STAT1 suppression and subsequent COX-2 and iNOS inhibition. Apigenin also exhibited synergistic activity in combination with doxorubicin toward HEK293-STAT1 cells. Apigenin exerted excellent growth-inhibitory activity against MM cells in a concentration-dependent manner with the greatest activity toward NCI-H929 (IC50 value: 10.73 ± 3.21 µM). Apigenin induced apoptosis, cell cycle arrest, ferroptosis and autophagy in NCI-H929 cells. CONCLUSION: Apigenin may be a suitable candidate for MM treatment. The inhibition of the STAT1/COX-2/iNOS signaling pathway by apigenin is an important mechanism not only in the suppression of inflammation but also in induction of apoptosis.

Design of oral intestinal-specific alginate-vitexin nanoparticulate system to modulate blood glucose level of diabetic rats.

Vitexin of Ficus deltoidea exhibits intestinal α-glucosidase inhibitory and blood glucose lowering effects. This study designs oral intestinal-specific alginate nanoparticulate system of vitexin. Nanospray-dried alginate, alginate/stearic acid and alginate-C18 conjugate nanoparticles were prepared. Stearic acid was adopted to hydrophobize the matrix and minimize premature vitexin release in stomach, whereas C-18 conjugate as immobilized fatty acid to sustain hydrophobic effect and drug release. Nanoparticles were compacted with polyethylene glycol (PEG 3000, 10,000 and 20,000). The physicochemical, drug release, in vivo blood glucose lowering and intestinal vitexin content of nanoparticles and compact were determined. Hydrophobization of alginate nanoparticles promoted premature vitexin release. Compaction of nanoparticles with PEG minimized vitexin release in the stomach, with stearic acid loaded nanoparticles exhibiting a higher vitexin release in the intestine. The introduction of stearic acid reduced vitexin-alginate interaction, conferred alginate-stearic acid mismatch, and dispersive stearic acid-induced particle breakdown with intestinal vitexin release. Use of PEG 10,000 in compaction brought about PEG-nanoparticles interaction that negated initial vitexin release. The PEG dissolution in intestinal phase subsequently enabled particle breakdown and vitexin release. The PEG compacted nanoparticles exhibited oral intestinal-specific vitexin release, with positive blood glucose lowering and enhanced intestinal vitexin content in vivo.

Cyclodextrin pendant polymer as an efficient drug carrier for scutellarin.

A novel ß-cyclodextrin pendant polymer (ε-PL-CD), composed of poly(ε-lysine) (ε-PL) main chain and glycine-ß-cyclodextrin (Gly-CD) side chains, was prepared by a simple two-step procedure. The ε-PL-CD was investigated as a drug carrier of hydrophobic drug scutellarin (SCU). The characterization and complexation mode of the SCU:ε-PL-CD were researched in both solution and solid state by means of photoluminescence spectroscopy, 1H and 2D NMR, X-Ray powder diffraction (XRPD), thermal gravimetric analysis, Particle size and Zeta potential. The solubility test indicated that the solubilizing ability of SCU:ε-PL-CD was significantly improved compared with SCU:ß-CD and free SCU. Besides, in vitro cell experiment, it was found that SCU:ε-PL-CD has a strong inhibitory effect on the growth and invasion of tumor cells. The present study provides useful information for ε-PL-CD as a drug carrier material.

Apigenin-Loaded Solid Lipid Nanoparticle Attenuates Diabetic Nephropathy Induced by Streptozotocin Nicotinamide Through Nrf2/HO-1/NF-kB Signalling Pathway.

BACKGROUND: Apigenin is known to have a broad-spectrum efficacy in oxidative stress and conditions due to inflammation, although weak absorption, fast metabolic rate and a fast elimination (systemic) limit the pharmacological efficacy of this drug. Hence, we propose the usage of highly bioavailable Apigenin-solid lipid nanoparticles (SLNPs) to recognize such limitations. The defensive function of Apigenin-SLNPs on renal damage induced by streptozotocin (STZ) in animals was studied. MATERIALS AND METHODS: We initially injected the rats with 35 mg kg-1 streptozocin intraperitoneally, and after 7 days, the rats were then injected 150 mg kg-1 of metformin intragastrically followed by a once-daily intragastric dose of Apigenin-SLNP (25 or 50 mg kg-1) for a continuous period of 30 days. We then measured the level of insulin and blood glucose, superoxide dismutase, catalase and malondialdehyde in the tissues of the kidney. We also observed messenger-RNA expression of Interleukin-1ß, Interleukin-6 and Tumor Necrosis Factor-alpha in renal tissue through RT-PCR technique. Moreover, H&E staining and Western blotting observed the histopathological variations and protein expression of nuclear factor erythroid 2-related factor 2/heme oxygenase/Nuclear Factor-κB signaling pathway, respectively. RESULTS: An enhancement in the expressing of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 and a suppression in the expression of Nuclear Factor-κB occurred due to Apigenin-SLNPs treatment, which was a result of the protective mechanism of Apigenin-SLNPs which is because of not only its anti-inflammatory function (by inhibition of release of inflammatory factors) but also their anti-oxidant activity (through reduction of lipid peroxidation production). CONCLUSION: We found that a protective effect on diabetic nephropathy was shown due to Apigenin-SLNPs, in rats induced with streptozocin maybe through the pathway of nuclear factor erythroid 2-related factor 2/heme oxygenase-1/Nuclear Factor-κB.

Apigenin by targeting hnRNPA2 sensitizes triple-negative breast cancer spheroids to doxorubicin-induced apoptosis and regulates expression of ABCC4 and ABCG2 drug efflux transporters.

Acquired resistance to doxorubicin is a major hurdle in triple-negative breast cancer (TNBC) therapy, emphasizing the need to identify improved strategies. Apigenin and other structurally related dietary flavones are emerging as potential chemo-sensitizers, but their effect on three-dimensional TNBC spheroid models has not been investigated. We previously showed that apigenin associates with heterogeneous ribonuclear protein A2/B1 (hnRNPA2), an RNA-binding protein involved in mRNA and co-transcriptional regulation. However, the role of hnRNPA2 in apigenin chemo-sensitizing activity has not been investigated. Here, we show that apigenin induced apoptosis in TNBC spheroids more effectively than apigenin-glycoside, owing to higher cellular uptake. Moreover, apigenin inhibited the growth of TNBC patient-derived organoids at an in vivo achievable concentration. Apigenin sensitized spheroids to doxorubicin-induced DNA damage, triggering caspase-9-mediated intrinsic apoptotic pathway and caspase-3 activity. Silencing of hnRNPA2 decreased apigenin-induced sensitization to doxorubicin in spheroids by diminishing apoptosis and partly abrogated apigenin-mediated reduction of ABCC4 and ABCG2 efflux transporters. Together these findings provide novel insights into the critical role of hnRNPA2 in mediating apigenin-induced sensitization of TNBC spheroids to doxorubicin by increasing the expression of efflux transporters and apoptosis, underscoring the relevance of using dietary compounds as a chemotherapeutic adjuvant.

Flavonoids potentiated anticancer activity of cisplatin in non-small cell lung cancer cells in vitro by inhibiting histone deacetylases.

AIMS: Cisplatin is the mainstay of first-line treatment for advanced non-small cell lung cancer (NSCLC). Accumulating evidence suggests that flavonoids inhibit histone deacetylase (HDAC) to mediate their anticancer effect in various cancer types. The study was conducted to investigate the inhibition of HDAC and the modulation of apoptotic and cell cycle regulatory genes by selected flavonoids to potentiate the anticancer effect of cisplatin. MAIN METHODS: Combinations of cisplatin and selected flavonoids were investigated in three NSCLC cell lines (A549, H460, and H1299). Sulforhodamine B assay was used to evaluate cytotoxicity of drug combinations. Western blot analysis was conducted to evaluate histone acetylation. Flow cytometric assays were used to investigate the apoptotic and cell cycle effect. Chromatin immunoprecipitation assay was performed to elucidate the binding of transcription factors to promoters of selected apoptotic and cell cycle regulatory genes. KEY FINDINGS: Apigenin was found to exhibit the strongest HDAC inhibitory effect among all flavonoids tested. Cisplatin-apigenin combination was shown to produce significantly more S phase prolongation and G2/M cell cycle arrest, and apoptosis compared with cisplatin or apigenin alone, by inducing p21 and PUMA, respectively. More pronounced effect was observed in p53-proficient than p53-null NSCLC cells. Mechanistically, apigenin was found to reduce the binding of HDAC1 but increase the association of RNA polymerase II and Sp1 to p21 and PUMA promoters. SIGNIFICANCE: Our findings provide a better insight about the mechanism contributing to the HDAC inhibitory effect of apigenin to potentiate anticancer effect of cisplatin by inducing apoptosis and cell cycle arrest.

Protective effect of apigenin magnesium complex on H2O2-induced oxidative stress and inflammatory responses in rat hepatic stellate cells.

Context: Apigenin displays antioxidant and anti-inflammatory effects. However, effects of apigenin magnesium (AM) complex on these aspects remain unknown.Objective: This study investigated the effects of AM complex on oxidative stress and inflammatory responses in hydrogen peroxide (H2O2)-induced rat hepatic stellate cells (HSCs).Materials and methods: The antioxidant and anti-inflammatory effects of AM complex at concentrations of 0.625, 1.25, and 2.5 mg/mL were evaluated, comparing to HSCs treated by H2O2 alone. Cell viability, reactive oxygen species (ROS), the activity of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), nitric oxide (NO), interleukin 6 (IL-6), and nuclear factor-kappa B (NF-κB) levels were measured. Moreover, cell apoptosis, mRNA expression levels of transforming growth factor-ß (TGF-ß), NF-κB, and inducible nitric oxide synthase (iNOS) were assessed.Results: AM complex significantly inhibited oxidative stress and inflammatory response at concentrations of 0.625, 1.25, and 2.5 mg/mL (IC50 = 1.679 mg/mL). AM complex elevated the survival rate of H2O2-treated HSCs and had no toxic effects on HSCs. AM complex also promoted SOD activity and GSH levels but suppressed ROS, MDA, and NO levels. Additionally, AM complex decreased IL-6 and NF-κB levels, gene expression of TGF-ß, NF-κB, and iNOS, as well as induced apoptosis of HSCs.Discussion and conclusions: Data indicated that AM complex mitigated oxidative stress and inflammatory responses on H2O2-treated HSCs, suggesting that AM complex is a possible candidate for anti-hepatic diseases. Additional efforts, both in vivo and in humans, are required to assess of AM complex as a potential therapeutic drug in liver diseases.

Luteolin and Apigenin Attenuate LPS-Induced Astrocyte Activation and Cytokine Production by Targeting MAPK, STAT3, and NF-κB Signaling Pathways.

Astrocytes release biologically active substances that cause inflammation in neurodegenerative diseases. The present study investigated the effects of two flavonoids (apigenin and luteolin) on the production of IL-31 and IL-33 in lipopolysaccharide (LPS)-activated astrocytes. Cell viability was investigated using EZ-Cytox assay, mRNA expressions of IL-31 and IL-33 were analyzed by RT-PCR, protein expressions were analyzed by western blot, and cytokine secretion was analyzed by ELISA. Apigenin and luteolin prevented astrocyte activation and inhibited mRNA and protein expression and secretion of IL-31 and IL-33 in the LPS-treated astrocytes. Apigenin's suppression of ERK, NF-κB, and STAT3 activations was responsible for the inhibition of IL-31 and IL-33, while luteolin's suppression of JNK, p38, ERK, NF-κB, and STAT3 activations was responsible for the inhibition of IL-31 in the astrocytes. Also, luteolin's suppression of ERK, NF-κB, and STAT3 activations inhibited IL-33 production in the activated astrocytes. In addition, apigenin and luteolin also prevented the translocation of activated STAT3 and NF-κB to the nucleus of the activated astrocytes and subsequently affected their DNA binding activities. The results suggest that apigenin and luteolin may have potentials as neuroprotective agents for the treatment of diseases involving astrocyte activation and detrimental production of IL-31 and IL-33.