Metabolic reprogramming is a common phenomenon in cancer, with aerobic glycolysis being one of its important characteristics. Hypoxia-inducible factor-1α (HIF1Α) is thought to play an important role in aerobic glycolysis. Meanwhile, naringin is a natural flavanone glycoside derived from grapefruits and many other citrus fruits. In this work, we identified glycolytic genes related to HIF1Α by analyzing the colon cancer database. The analysis of extracellular acidification rate and cell function verified the regulatory effects of HIF1Α overexpression on glycolysis, and the proliferation and migration of colon cancer cells. Moreover, naringin was used as an inhibitor of colon cancer cells to illustrate its effect on HIF1Α function. The results showed that the HIF1Α and enolase 2 (ENO2) levels in colon cancer tissues were highly correlated, and their high expression indicated a poor prognosis for colon cancer patients. Mechanistically, HIF1Α directly binds to the DNA promoter region and upregulates the transcription of ENO2; ectopic expression of ENO2 increased aerobic glycolysis in colon cancer cells. Most importantly, we found that the appropriate concentration of naringin inhibited the transcriptional activity of HIF1Α, which in turn decreased aerobic glycolysis in colon cancer cells. Generally, naringin reduces glycolysis in colon cancer cells by reducing the transcriptional activity of HIF1Α and the proliferation and invasion of colon cancer cells. This study helps to elucidate the relationship between colon cancer progression and glucose metabolism, and demonstrates the efficacy of naringin in the treatment of colon cancer.
Glycolysis ; Colonic Neoplasms/metabolism* ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Phosphopyruvate Hydratase/metabolism* ; Flavanones/pharmacology* ; Cell Line, Tumor ; Databases, Genetic ; Cell Proliferation/drug effects* ; Transfection ; Warburg Effect, Oncologic

To screen and identify the endophytic fungal strains that could promote the accumulation of flavonoids in the callus of Scutellaria baicalensis. Seventeen endophytic fungal strains from S. baicalensis were used to prepare mycelium elicitors and fermentation broth elicitors. Their effects on flavonoid accumulation in S. baicalensis callus were then determined. The results showed that the fermentation broth elicitors of two strains(CL79, CL105) promoted the accumulation of flavonoids. The fermentation broth elicitor of CL79 significantly promoted accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 37.8%, 40.4%, 44.7%, and 42.2%(vs. blank), respectively. Similarly, the fermentation broth elicitor of CL105 significantly promoted the accumulation of baicalin, wogonoside, baicalein, and wogonin, with the maximum levels increased by 78.1%, 140.9%, 275.6%, and 208.5%(vs. blank), respectively. CL79 was identified as Alternaria alternata, and CL105 as Fusarium solani. The fermentation broth elicitors of A. alternata CL79 and F. solani CL105 were able to promote the flavonoid accumulation in the callus of S. baicalensis, which enriched the resources of endophytic fungi and provided candidate strains for the development of microbial fertili-zers for improving the quality of S. baicalensis.
Scutellaria baicalensis ; Plant Roots ; Flavanones ; Flavonoids

Flavonoids have a variety of biological activities and have important applications in food, medicine, cosmetics, and many other fields. Naringenin is a platform chemical for the biosynthesis of many important flavonoids. Ubiquitination plays a pivotal role in the post-translational modification of proteins and participates in the regulation of cellular activities. Ubiquitinated proteins can be degraded by the ubiquitin-protease system, which is important for maintaining the physiological activities of cells, and may also exert a significant impact on the expression of exogenous proteins. In this study, a real-time in-situ detection system for ubiquitination modification has been established in Saccharomyces cerevisiae by using a fluorescence bimolecular complementation approach. The ubiquitination level of protein was characterized by fluorescence intensity. By using the approach, the potential ubiquitination sites of proteins involved in the naringenin biosynthesis pathway have been obtained. The lysine residues of the relevant ubiquitination sites were mutated to arginine to reduce the ubiquitination level. The mutants of tyrosine ammonia-lyase (FjTAL) and chalcone synthase (SjCHS, SmCHS) showed decreased fluorescence, suggested that a decreased ubiquitination level. After fermentation verification, the S. cerevisiae expressing tyrosine ammonia-lyase FjTAL mutant FjTAL-K487R accumulated 74.2 mg/L p-coumaric acid at 72 h, which was 32.3% higher than that of the original FjTAL. The strains expressing chalcone synthase mutants showed no significant change in the titer of naringenin. The results showed that mutation of the potential ubiquitination sites of proteins involved in the naringenin biosynthesis pathway could increase the titer of p-coumaric acid and have positive effect on naringenin biosynthesis.
Biosynthetic Pathways ; Flavanones/metabolism* ; Saccharomyces cerevisiae/metabolism* ; Ubiquitination

OBJECTIVE: To identify whether naringenin plays a protective role during thoracic aneurysm formation in Marfan syndrome. METHODS: To validate the effect of naringenin, Fbn1^C1039G/+ mice, the mouse model of Marfan syndrome, were fed with naringenin, and the disease progress was evaluated. The molecular mechanism of naringenin was further investigated via in vitro studies, such as bioluminescence resonance energy transfer (BRET), atomic force microscope and radioligand receptor binding assay. RESULTS: Six-week-old Fbn1^C1039G/+ mice were fed with naringenin for 20 weeks. Compared with the control group, naringenin significantly suppressed the aortic expansion [Fbn1^C1039G/+ vs. Fbn1^C1039G/++naringenin: (2.49±0.47) mm, n=18 vs. (1.87±0.19) mm, n=22, P < 0.05], the degradation of elastin, and the expression and activity of matrix metalloproteinase 2 (MMP2) and MMP9 in the ascending aorta of Fbn1^C1039G/+ mice. Besides, treatment with naringenin for 6 weeks also attenuated the disease progress among the 20-week-old Fbn1^C1039G/+ mice with established thoracic aortic aneurysms [Fbn1^C1039G/+ vs. Fbn1^C1039G/++naringenin: (2.24±0.23) mm, n=8 vs. (1.90±0.17) mm, n=8, P < 0.05]. To understand the underlying molecular mechanisms, we examined the effects of naringenin on angiotensin Ⅱ type 1 receptor (AT1) signaling and transforming growth factor-β (TGF-β) signaling respectively, which were the dominant signaling pathways contributing to aortopathy in Marfan syndrome as previously reported. The results showed that naringenin decreased angiotensin Ⅱ (Ang Ⅱ)-induced phosphorylation of protein kinase C (PKC) and extracellular regulating kinase 1/2 (ERK1/2) in HEK293A cell overexpressing AT1 receptor. Moreover, naringenin inhibited Ang Ⅱ-induced calcium mobilization and uclear factor of activated T-cells (NFAT) signaling. The internalization of AT1 receptor and its binding to β-arrestin-2 with Ang Ⅱ induction were also suppressed by naringenin. As evidenced by atomic force microscope and radioligand receptor binding assay, naringenin inhibited Ang Ⅱ binding to AT1 receptor. In terms of TGF-β signaling, we found that feeding the mice with naringenin decreased the phosphorylation of Smad2 and ERK1/2 as well as the expression of TGF-β downstream genes. Besides, the serum level of TGF-β was also decreased by naringenin in the Fbn1^C1039G/+ mice. Furthermore, we detected the effect of naringenin on platelet, a rich source of TGF-β, both in vivo and in vitro. And we found that naringenin markedly decreased the TGF-β level by inhibiting the activation of platelet. CONCLUSION Our study showed that naringenin has a protective effect on thoracic aortic aneurysm formation in Marfan syndrome by suppressing both AT1 and TGF-β signaling.
Angiotensin II/metabolism* ; Animals ; Aortic Aneurysm, Thoracic/prevention & control* ; Calcium/metabolism* ; Disease Models, Animal ; Elastin/metabolism* ; Fibrillin-1/metabolism* ; Flavanones ; Marfan Syndrome/metabolism* ; Matrix Metalloproteinase 2 ; Matrix Metalloproteinase 9 ; Mice ; Mice, Inbred C57BL ; Protein Kinase C/metabolism* ; Receptor, Angiotensin, Type 1/metabolism* ; Transforming Growth Factor beta/metabolism* ; Transforming Growth Factors/metabolism* ; beta-Arrestins/metabolism*

OBJECTIVE: To investigate the effects of wogonoside on high glucose-induced dysfunction of human retinal microvascular endothelial cells (hRMECs) and streptozotocin (STZ)-induced diabetic retinopathy in rats and explore the underlying molecular mechanism. METHODS: HRMECs in routine culture were treated with 25 mmol/L mannitol or exposed to high glucose (30 mmol/L glucose) and treatment with 10, 20, 30, 40 μmol/L wogonoside. CCK-8 assay and Transwell assay were used to examine cell proliferation and migration, and the changes in tube formation and monolayer cell membrane permeability were tested. ROS, NO and GSH-ST kits were used to evaluate oxidative stress levels in the cells. The expressions of IL-1β and IL-6 in the cells were examined with qRT-PCR and ELISA, and the protein expressions of VEGF, HIF-1α and SIRT1 were detected using Western blotting. We also tested the effect of wogonoside on retinal injury and expressions of HIF-1α, ROS, VEGF, TNF-α, IL-1β, IL-6 and SIRT1 proteins in rat models of STZ-induced diabetic retinopathy. RESULTS: High glucose exposure caused abnormal proliferation and migration, promoted angiogenesis, increased membrane permeability (P < 0.05), and induced inflammation and oxidative stress in hRMECs (P < 0.05). Wogonoside treatment concentration-dependently inhibited high glucose-induced changes in hRMECs. High glucose exposure significantly lowered the expression of SIRT1 in hRMECs, which was partially reversed by wogonoside (30 μmol/L) treatment; interference of SIRT1 obviously attenuated the inhibitory effects of wogonoside against high glucose-induced changes in proliferation, migration, angiogenesis, membrane permeability, inflammation and oxidative stress in hRMECs. In rat models of STZ-induced diabetic retinopathy, wogonoside effectively suppressed retinal thickening (P < 0.05), alleviated STZ-induced retinal injury, and increased the expression of SIRT1 in the retinal tissues (P < 0.001). CONCLUSION Wogonoside alleviates retinal damage caused by diabetic retinopathy by up-regulating SIRT1 expression.
Animals ; Diabetes Mellitus/metabolism* ; Diabetic Retinopathy/metabolism* ; Endothelial Cells ; Flavanones ; Glucose/pharmacology* ; Glucosides ; Inflammation/metabolism* ; Interleukin-6/metabolism* ; Neovascularization, Pathologic/metabolism* ; Rats ; Reactive Oxygen Species/metabolism* ; Sirtuin 1/metabolism* ; Streptozocin/pharmacology* ; Vascular Endothelial Growth Factor A/metabolism*

The present study established an RP-HPLC method for simultaneous determination of two active components in Qingfei Paidu Granules and investigated the transfer rates of neohesperidin and naringin in the preparation process to provide references for improving the quality control standard and production of Qingfei Paidu Granules.RP-HPLC was performed on a YMC Triart C_(18) column(4.6 mm×150 mm, 5 μm)with column temperature of 30 ℃, acetonitrile(A) and 0.2% phosphoric acid solution(B) as mobile phases for gradient elution at a flow rate of 1.0 mL·min~(-1) and detection wavelength of 284 nm.Good linearity was observed for naringin at 0.10-1.0 μg(R~2=0.999 9) and neohesperidin at 0.12-1.2 μg(R~2=0.999 9).The average recovery of naringin was 99.52% with an RSD of 1.2%, and that of neohesperidin was 100.8% with an RSD of 1.2%.The transfer rates of naringin and neohesperidin between medicinal materials, extracts, concentrates, and granules were measured by this method.The average transfer rate of naringin from medicinal materials to granules was 54.89%±4.38%, and that of neohesperidin was 57.63%±5.88%.The process from medicinal materials to extracts was presumedly the key link affecting the whole preparation process.The established method is simple and sensitive and can be adopted for the quality control of Qingfei Paidu Granules.Meanwhile, it can be used to investigate the transfer rate of neohesperidin and naringin in the preparation of Qingfei Paidu Granules, and further improve the quality control standard of Aurantii Fructus Immaturus in Qingfei Paidu Granules.
Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal ; Flavanones ; Hesperidin/analogs & derivatives*

OBJECTIVE: To investigate the effect of baicalein on polymicrobial sepsis-induced immune dysfunction and organ injury. METHODS: A sepsis model was induced in Sprague-Dawley rats via caecal ligation and puncture (CLP). Specific pathogen free rats were randomly divided into a sham group, CLP group and CLP + baicalein (Bai) group (n=16 each). Rats in the CLP + Bai group were intravenously injected with baicalein (20 mg/kg) at 1 and 10 h after CLP. Survival rate, bacterial load, and organ damage were assessed. Then each group was evaluated at 6, 12, and 24 h to investigate the effect of baicalein on immune cells and inflammatory cytokines in septic rats. RESULTS: Baicalein treatment significantly improved the survival of septic rats, decreased the bacterial burden, and moderated tissue damage (spleen, liver, and lung), as observed by haematoxylin and eosin staining. Septic rats treated with baicalein had strikingly increased proportions of CD3⁺CD4⁺ T cells and ratios of CD4⁺/CD8⁺ T cells in the peripheral blood and spleen (all P<0.05). Moreover, baicalein treatment decreased the apoptotic rate of whole white blood cells and spleen cells at 24 h after surgery (P<0.05). Baicalein significantly reduced the levels of tumor necrosis factor α and interleukin-6 (IL-6) and increased IL-10, and the expression levels of galectin 9 were also raised in the spleen (P<0.01). CONCLUSION Baicalein may be an effective immunomodulator that attenuates overwhelming inflammatory responses in severe abdominal sepsis.
Animals ; CD8-Positive T-Lymphocytes ; Flavanones ; Inflammation/drug therapy* ; Rats ; Rats, Sprague-Dawley ; Sepsis/drug therapy*

OBJECTIVE: To explore the effects of Eriodictyol to the growth, apoptosis and oxidative stress of Burkitt lymphoma (BL) cells and phosphorylation of protein kinase B (AKT) in children. METHODS: The effects of Eriodictyol (0, 1.25, 2.5, 5, 10, 20, 40, 80, 160, 320 μmol/L) to viability of BL cell line DG-75 cells were detected by CCK-8. The effects of Eriodictyol (0, 10, 20, 40 μmol/L) to the proliferation activity of DG-75, apoptosis rate, levels of apoptosis-related proteins, oxidative stress indexes ［superoxide dismutase (SOD), malondialdehyde (MDA)］, mitochondrial membrane potential (MMP) and phosphorylation level of phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycinm (mTOR) were detected by clony formation assay and Wester blot. RESULTS: When the treatment concentration of Eriodictyol was 20 μmol/L, the proliferation activity of the cells was decreased (P<0.05). The concentrations at 10, 20, 40 μmol/L were selected for subsequent experiments. Compared with 0 μmol/L Eriodictyol, the proliferation activity of DG-75, SOD activity, MMP, phosphorylation levels of PI3K, AKT and mTOR in 20 and 40 μmol/L Eriodictyol treatment groups were significantly decreased (P<0.05), while cells apoptosis rate, Cleaved-Caspase-3/Caspase-3, Bax/Bcl-2 and MDA level were significantly increased (P<0.05). CONCLUSION Eriodictyol may promote the mitochondrial apoptosis pathway by inhibiting the abnormal activation of PI3K/AKT/mTOR to reduce the proliferation activity of DG-75, and inhibit oxidative stress response to increase the apoptosis rate and play anti-tumor roles.
Apoptosis ; Flavanones ; Phosphatidylinositol 3-Kinases/metabolism* ; Signal Transduction

The exacerbation of progressive multiple sclerosis (MS) is closely associated with obstruction of the differentiation of oligodendrocyte progenitor cells (OPCs). To discover novel therapeutic compounds for enhancing remyelination by endogenous OPCs, we screened for myelin basic protein expression using cultured rat OPCs and a library of small-molecule compounds. One of the most effective drugs was pinocembrin, which remarkably promoted OPC differentiation and maturation without affecting cell proliferation and survival. Based on these in vitro effects, we further assessed the therapeutic effects of pinocembrin in animal models of demyelinating diseases. We demonstrated that pinocembrin significantly ameliorated the progression of experimental autoimmune encephalomyelitis (EAE) and enhanced the repair of demyelination in lysolectin-induced lesions. Further studies indicated that pinocembrin increased the phosphorylation level of mammalian target of rapamycin (mTOR). Taken together, our results demonstrated that pinocembrin promotes OPC differentiation and remyelination through the phosphorylated mTOR pathway, and suggest a novel therapeutic prospect for this natural flavonoid product in treating demyelinating diseases.
Animals ; Cell Differentiation ; Flavanones ; Mice ; Mice, Inbred C57BL ; Myelin Sheath/metabolism* ; Oligodendroglia/metabolism* ; Rats ; Remyelination ; Signal Transduction ; TOR Serine-Threonine Kinases/metabolism*

This study was to investigate the chemical constituents from the aerial parts of Thymus przewalskii. The chemical consti-tuents were separated and purified by column chromatography on silica gel, ODS, Sephadex LH-20 and semi-prepared HPLC, and their structures were determined by physicochemical properties and spectroscopic data. Four flavanones were isolated from the ethanol extract of the aerial parts of T. przewalskii, and identified as(2S)-5,6-dihydroxy-7,8,4'-trimethoxyflavanone(1), 5,4'-dihydroxy-6,7-dimethoxyflavanone(2),(2S)-5,4'-dihydroxy-7,8-dimethoxyflavanone(3), sakuranetin(4), respectively. Compound 1 was a new compound and its configuration was determined by CD spectrum, compound 3 was natural product which was isolated for the first time and their configurations were determined by CD spectra. Compound 2 was isolated from the genus Thymus for the first time and compound 4 was isolated from T. przewalskii for the first time. Furthermore, cytotoxicity test was assayed for the four flavanones. They exhibited weak cytotoxicity against human lung cancer cells(A549), with the IC_(50) from 74.5 to 135.6 μmol·L~(-1).
Chromatography, High Pressure Liquid ; Flavanones ; Humans