2'-Hydroxyflavanone

Liquid chromatography-tandem mass spectrometry analysis of oxidation of 2'-, 3'-, 4'- and 6-hydroxyflavanones by human cytochrome P450 enzymes.[Pubmed:33047997]

Xenobiotica. 2020 Oct 23:1-16.

2'-Hydroxyflavanone (2'OHFva), 3'OHFva, 4'OHFva, and 6OHFva, the major oxidative products of flavanone by human cytochrome P450 (P450, CYP) enzymes, were studied in regard to further oxidation by human CYP1A1, 1A2, 1B1.1, 1B1.3, and 2A6. The products formed were analyzed with LC-MS/MS and characterized by their positive ion fragmentations on mass spectrometry. Several di-hydroxylated flavanone (diOHFva) and di-hydroxylated flavone (diOHFvo) products, detected by analyzing parent ions at m/z 257 and 255, respectively, were found following incubation of these four hydroxylated flavanones with P450s. The m/z 257 products were produced at higher levels than the latter with four substrates examined. The structures of the m/z 257 products were characterized by LC-MS/MS product ion spectra, and the results suggest that 3'OHFva and 4'OHFva are further oxidized mainly at B-ring by P450s while 6OHFva oxidation was at A-ring. Different diOHFvo products (m/z 255) were also characterized by LC-MS/MS, and the results suggested that most of these diOHFvo products were formed through oxidation or desaturation of the diOHFva products (m/z 257) by P450s. Only when 4'OHFva (m/z 241) was used as a substrate, formation of 4'OHFvo (m/z 239) was detected, indicating that diOHFvo might also be formed through oxidation of 4'OHFvo by P450s. Finally, our results indicated that CYP1 family enzymes were more active than CYP2A6 in catalyzing the oxidation of these four hydroxylated flavanones, and these findings were supported by molecular docking studies of these chemicals with active sites of P450 enzymes.

2'-Hydroxyflavanone prevents LPS-induced inflammatory response and cytotoxicity in murine macrophages.[Pubmed:32800949]

Toxicol In Vitro. 2020 Dec;69:104966.

2'-Hydroxyflavanone (2-HF) is a natural flavonoid isolated from citrus fruits. Multiple studies have demonstrated that 2-HF with its anti-proliferative and pro-apoptotic effects prevent the growth of various cancers. Although 2-HF is a well known anti-oxidative and chemopreventive agent, its role as an anti-inflammatory agent is not well established. In this study, we examined the effect of 2-HF on LPS-induced cytotoxicity and inflammatory response in murine RAW 264.7 macrophages. Flow cytometry analysis showed that pre-treatment of RAW 264.7 macrophages with 2-HF significantly prevented LPS-induced macrophage apoptosis. 2-HF also prevented LPS-induced reactive oxygen species (ROS) and nitric oxide (NO) production, lipid peroxidation, and loss of mitochondrial membrane potential in murine macrophages. Most importantly, the release of multiple inflammatory cytokines and chemokines such as eotaxin, IL-2, IL-10, IL-12p40, LIX, IL-15, IL-17, MCP-1, and TNF-alpha induced by LPS in the macrophages was inhibited by 2-HF. 2-HF also prevented LPS-induced activation of protein kinases p38MAPK and SAPK/JNK. Apart from this, LPS-induced phosphorylation, nuclear translocation, and DNA-binding of the redox transcription factor, NF-kappaB, was prevented by 2-HF. Our results demonstrate that 2-HF by regulating ROS/MAPK/NF-kappaB prevents LPS-induced inflammatory response and cytotoxicity in murine macrophages suggesting that the need of potential development of 2-HF as an anti-inflammatory agent to ameliorate various inflammatory complications.

Preparation and evaluation of an ethylenediamine dicarboxyethyl diamido-bridged bis(beta-cyclodextrin)-bonded chiral stationary phase for high performance liquid chromatography.[Pubmed:32063276]

J Chromatogr A. 2020 May 24;1619:460937.

An ethylenediamine dicarboxyethyl diacetamido-bridged bis(beta-cyclodextrin) was firstly synthesized through the reaction of 6-deoxy-6-amino-beta-cyclodextrin (NH2-CD) with ethylenediaminetetraacetic dianhydride. Then it was bonded onto the surface of silica gel SBA-15 to obtain an ethylenediamine dicarboxyethyl diacetamido-bridged bis(beta-CD)-bonded chiral stationary phase (EBCDP). The structures of the bridged bis(beta-CD) and EBCDP were characterized by infrared spectroscopy, mass spectrometry, elemental analysis and thermogravimetric analysis, accordingly. The chiral chromatographic performances of EBCDP were systematically evaluated by separating 28 racemic analytes in the reversed-phase or polar organic mode, including eight flavanones, eight bolckers, five dansyl-amino acids, three DL-amino acids and four other common drugs. As a result, the relatively high enantioselectivity of EBCDP was observed in comparison with a native beta-CD-CSP (CDSP). All selected analytes were separated on EBCDP, of which 20 analytes had resolutions up to baseline, 2'-hydroxyflavanone and arotinolol had resolutions up to 4.35 and 2.05 in about 30 min, respectively, whereas CDSP only separated 11 analytes with low resolutions (0.55~1.69). Moreover, EBCDP was able to utilize the complexation of the bridging linker (ethylenediamine dicarboxyethyl diamide group, EDTA-based) to realize direct separations of DL-amino acids with a mobile phase containing copper ion (Cu(2+)), which was similar to the chiral ligand exchange chromatography. Unlike the native cyclodextrin with small cavity (~242 A(3)), the bridged bis(beta-CD) combined two beta-CD units with a bridging linker, having a well-organized "pseudo-cavity" as an organic whole to encapsulate more analytes, which made EBCDP have broad-spectrum applications in chiral separations.

Preparation and Evaluation of a Cholesterol Derivatized beta-Cyclodextrin-bonded Phase for Achiral and Chiral HPLC.[Pubmed:31866607]

Anal Sci. 2020 Jun 10;36(6):687-695.

A cholesterol mono-derivatized beta-cyclodextrin was synthesized and bonded onto silica gel (SBA-15) to obtain a cholesterol mono-derivatized beta-cyclodextrin-bonded stationary phase (CHCDP). The chemical structures of mono-derivatized beta-cyclodextrin and CHCDP were characterized by infrared spectroscopy, mass spectrometry, elemental analysis and thermogravimetric analysis, correspondingly. Furthermore, the separation ability of CHCDP in terms of achiral compounds was systematically evaluated by separating benzene homologs, polycyclic aromatic hydrocarbons (PAHs) and some positional isomers. As a result, CHCDP completely separated five benzene homologs and nine PAHs within 30 min under the reversed-phase. In addition, the chiral chromatographic property of CHCDP was also evaluated by separating some racemic compounds including flavanones, triazoles, beta-blockers, etc. The results showed that the CHCDP exhibited high enantioselectivities towards most of selected analytes. The enantioresolutions were in the range from 1.43 to 2.51 on CHCDP. Especially the resolutions of 2'-hydroxyflavanone, hexaconazole, Dns-serine and atenolol were as high as 1.94, 1.91, 2.15 and 1.57, respectively. Obviously, the CHCDP was a versatile stationary phase with chiral and achiral separation capabilities in multi-mode chromatography, which was related to the introduction of cholesterol to the port of cyclodextrin, enhancing the hydrophobic interaction of cyclodextrin with achiral compounds, while maintaining the inclusion complexation of it with chiral compounds as well.

2'-Hydroxyflavanone inhibits the progression of pancreatic cancer cells and sensitizes the chemosensitivity of EGFR inhibitors via repressing STAT3 signaling.[Pubmed:31811906]

Cancer Lett. 2020 Feb 28;471:135-146.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, and chemotherapy is still an important treatment. It is urgent to develop new medicines because of the limitation and side effects of chemotherapy. 2'-Hydroxyflavanone (2HF) is a citrus-bioflavonoid that is considered to have anti-cancer efficacy. Compared to human pancreatic ductal epithelial cells hTERT-HPNE, more significant growth-inhibitory effects were seen in PDAC cells BxPC-3 and MIA PaCa-2. We showed that apoptosis was induced and that the cell cycle was arrested when cells were treated with 2HF. The expression of the molecular proteins cleaved PARP, cleaved Caspase3, Bax, Bcl-2, CyclinD1, and p27 changed correspondingly. Also, we observed anti-metastatic effects and changes in MMP9, E-cadherin, N-cadherin and Vimentin when cells were treated with a low dose of 2HF. Suppression of STAT3 and EGFR phosphorylation was also identified as a result of treatment with a combination of 2HF and EGFR inhibitors. The in vivo antitumor effects in KPC mice were consistent with those observed in vitro. 2HF has impactful anti-cancer efficacy and sensitizes human pancreatic cancer cells to EGFR inhibitors through the inhibition of STAT3.

Topical 2'-Hydroxyflavanone for Cutaneous Melanoma.[Pubmed:31615091]

Cancers (Basel). 2019 Oct 14;11(10). pii: cancers11101556.

2'-hydroxyflavanone (2HF) is a dietary flavonoid with anticancer activity towardsmultiple cancers. Here, we report that topically applied 2HF inhibits the growth of intradermalimplants of melanoma in immunocompetent mice. 2HF induced apoptosis and inhibited the growthof the human SK-MEL-24 as well as murine B16-F0 and B16-F10 melanoma cell lines in vitro.Apoptosis was associated with depletion of caspase-3, caspase-9, and PARP1 in B16-F0 and SKMEL-24 cells. Caspase-9 and MEKK-15 were undetected even in untreated B16-F10 cells. Signalingproteins TNFalpha, and phospho-PDGFR-beta were depleted in all three cell lines; MEKK-15 was depletedby 2HF in SK-MEL-24 cells. 2HF enhanced sunitinib (an MEK and PDGFR-beta inhibitor) and AZD2461 (a PARP1 inhibitor) cytotoxicity. 2HF also depleted the Ral-regulated, stress-responsive,antiapoptotic endocytic protein RLIP76 (RALBP1), the inhibition of which has previously beenshown to inhibit B16-F0 melanoma growth in vivo. Functional inhibition of RLIP76 was evidentfrom inhibition of epidermal growth factor (EGF) endocytosis by 2HF. We found that topicallyapplied 2HF-Pluronic Lecithin Organogel (PLO) gel inhibited B16-F0 and B16-F10 tumorsimplanted in mice and caused no overt toxicity despite significant systemic absorption. 2HFtreatment reduced phospho-AKT, vimentin, fibronectin, CDK4, cyclinB1, and BCL2, whereas itincreased BIM and phospho-AMPK in excised tumors. Several cancer signals are controlled byendocytosis, a process strongly inhibited by RLIP76 depletion. We conclude that 2HF-PLO gel maybe useful for topical therapy of cutaneous metastases of melanoma and could enhance theantineoplastic effects of sunitinib and PARP1 inhibitors. The mechanism of action of 2HF inmelanoma overlaps with RLI76 inhibitors.

Position Impact of Hydroxy Groups on Spectral, Acid-Base Profiles and DNA Interactions of Several Monohydroxy Flavanones.[Pubmed:31443449]

Molecules. 2019 Aug 22;24(17). pii: molecules24173049.

Structure-related biological activities of flavanones are still considered largely unexplored. Since they exhibit various medicinal activities, it is intriguing to enter deeper into their chemical structures, electronic transitions or interactions with some biomolecules in order to find properties that allow us to better understand their effects. Little information is available on biological activity of flavanone and its monohydroxy derivatives in relation to their physicochemical properties as spectral profiles, existence of protonated/deprotonated species under pH changes or interaction with Calf Thymus DNA. We devoted this work to research demonstrating differences in the physicochemical properties of the four flavanones: flavanone, 2'-hydroxyflavanone, 6-hydroxyflavanone and 7-hydroxyflavanone and linking them to their biological activity. Potentiometric titration, UV-Vis spectroscopy were used to investigate influence of pH on acid-base and spectral profiles and to propose the mode of interaction with DNA. Cyclic voltammetry was applied to evaluate antioxidant potentiality and additionally, theoretical DFT(B3LYP) method to disclose electronic structure and properties of the compounds. Molecular geometries, proton affinities and pKa values have been determined. According to computational and cyclic voltammetry results we could predict higher antioxidant activity of 6-hydroxyflavanone with respect to other compounds. The values of Kb intrinsic binding constants of the flavanones indicated weak interactions with DNA. Structure-activity relationships observed for antioxidant activity and DNA interactions suggest that 6-hydroxyflavanone can protect DNA against oxidative damage most effectively than flavanone, 2'-hydroxyflavanone or 7-hydroxyflavanone.

Synergistic efficacy of RLIP inhibition and 2'-hydroxyflavanone against DMBA-induced mammary carcinogenesis in SENCAR mice.[Pubmed:31006917]

Mol Carcinog. 2019 Aug;58(8):1438-1449.

Substantial evidence suggests that 7,12-dimethylbenzanthracene (DMBA)-induced mammary carcinogenesis in mice mimics human breast cancer (BC) in many respects. Therefore, it has been used extensively to evaluate preventive and therapeutic agents for human BC. Mammary carcinogenesis induced by DMBA administration in female SENsitive to CARcinogen (SENCAR) mice was characterized by histopathological analysis of the mammary glands and alterations to the phosphatidylinositol 3-kinase/protein kinase B/cyclin-dependent kinase 1 (PI3K/Akt/CDK1) pathway. We recently reported that 2'-hydroxyflavanone (2HF) is a promising diet-derived chemotherapeutic agent that suppresses BC growth in vitro and in vivo by targeting a 76 kDa ral-interacting protein (RLIP). The objective of the current study was to investigate the synergistic anticarcinogenic effects of RLIP inhibition/depletion and 2HF in an in vivo model of DMBA-induced mammary carcinogenesis in SENCAR mice. Mice were given 2HF (50 mg/kg, bw, orally on alternate days), RLIP antibody (Rab; 5 mg/kg, bw, ip weekly), RLIP antisense (RAS; 5 mg/kg, b.w., ip weekly), or a combination of 2HF + Rab + RAS. Animals were monitored daily, and 7 days after the first appearance of moribund behavior, tissues were harvested for morphological and immunohistological analysis. Western blot analyses were performed to determine the expression of anti- and proapoptotic proteins in the mammary glands. Our results reveal that 2HF, RAS, and Rab significantly prevented the carcinogenic effects of DMBA administration in the mammary glands and other organs. Further, mice treated with a combination of 2HF + RAS + Rab exhibited no carcinogenic effect of DMBA as compared to either or the single agent-treated mice. This study demonstrates for the first time the anticarcinogenic effects of 2HF and RLIP inhibition/depletion in vivo in a novel DMBA-induced model of BC in SENCAR mice and provides the rationale for further clinical investigation.

RLIP inhibition suppresses breast-to-lung metastasis.[Pubmed:30684594]

Cancer Lett. 2019 Apr 10;447:24-32.

Breast tumor metastasis is a leading cause of cancer-related deaths worldwide. Breast cancer (BC) cells frequently metastasize to the lungs, where they pose a formidable therapeutic challenge. In the current study, we evaluated the anti-proliferative and anti-metastatic effects of 2'-hydroxyflavanone (2HF) and RLIP inhibition in an array of triple-negative BC cell lines and an orthotopic mouse model of breast-to-lung metastasis. Compared to control treatment, RLIP inhibition reduced in-vitro cell viability and suppressed the migratory and invasive potential of BC cells. In-vitro studies showed that 2HF treatment reduced the expression of RLIP, KRAS, pERK, pSTAT3, and pP70S6K. Further, mice orthotopically implanted with lung-seeking luciferase-expressing TMD231 cells were treated with 2HF (50 mg/kg, b.w.), RLIP antisense (RAS; 5 mg/kg, b.w.), RLIP antibody (Rab; 5 mg/kg, b.w.) or a combination of 2HF + RAS + Rab. 2HF-, RAS-, and Rab-treated mice exhibited significantly lower primary tumor weight and reduced lung metastasis compared to control mice. Mice treated with a combination of 2HF + RAS + Rab exhibited no metastasis and significantly lower tumor weight than the single agent-treated mice. Collectively, our results suggest that 2HF has potential to be combined with RLIP inhibition/depletion to more effectively suppress primary breast tumor growth and metastasis to the lungs.

Anticancer activity of 2'-hydroxyflavanone towards lung cancer.[Pubmed:30546837]

Oncotarget. 2018 Nov 16;9(90):36202-36219.

In previous studies, we found that 2'-hydroxyflavonone (2HF), a citrus flavonoid, inhibits the growth of renal cell carcinoma in a VHL-dependent manner. This was associated with the inhibition of glutathione S-transferases (GSTs), the first step enzyme of the mercapturic acid pathway that catalyzes formation of glutathione-electrophile conjugates (GS-E). We studied 2HF in small cell (SCLC) and non-small cell (NSCLC) lung cancer cell lines for sensitivity to 2HF antineoplastic activity and to determine the role of the GS-E transporter Rlip (Ral-interacting protein; RLIP76; RALBP1) in the mechanism of action of 2HF. Our results show that 2HF induced apoptosis in both histological types of lung cancer and inhibited proliferation and growth through suppression of CDK4, CCNB1, PIK3CA, AKT and RPS6KB1 (P70S6K) signaling. Increased E-cadherin and reduced fibronectin and vimentin indicated inhibition of epithelial-mesenchymal transition. Additionally, 2HF inhibited efflux of doxorubicin and increased its accumulation in the cells, but did not add to the transport inhibitory effect of anti-Rlip antibodies alone. Binding of Rlip to 2HF was evident from successful purification of Rlip by 2HF affinity chromatography. Consistent with increased drug accumulation, combined treatment with 1-chloro-2, 4-dinitrobenzene, reduced the GI50 of 2HF by an order of magnitude. Results of in-vivo nude mouse xenograft studies of SCLC and NSCLC, which showed that orally administered 2HF inhibited growth of both histological types of lung cancer, confirmed in-vitro study results. Our result suggest that Rlip inhibition is likely a mechanism of action. Our findings are basis of proposing 2HF as therapeutic or preventative drug for lung cancer.

2'-Hydroxyflavanone activity in vitro and in vivo against wild-type and antimony-resistant Leishmania amazonensis.[Pubmed:30521527]

PLoS Negl Trop Dis. 2018 Dec 6;12(12):e0006930.

BACKGROUND: To overcome the current problems in leishmaniasis chemotherapy, natural products have become an interesting alternative over the past few decades. Flavonoids have been studied as promising family of compounds for leishmaniasis treatment. 2'-Hydroxyflavanone (2HF) is a flavanone, a class of flavonoid that has shown promising results in cancer studies. In this study, we demonstrated the effects of 2HF in vitro and in vivo against wild-type and antimony-resistant Leishmania amazonensis promastigotes. METHODOLOGY/PRINCIPAL FINDINGS: 2HF was effective against promastigotes and the intracellular amastigote form, decreasing the infection index in macrophages infected with wild-type and antimony-resistant promastigotes, but it was not toxic to macrophages. In silico analysis indicated 2HF as a good oral candidate for leishmaniasis treatment. In vivo, 2HF was able to reduce the lesion size and parasite load in a murine model of cutaneous leishmaniasis using wild-type and antimony-resistant promastigotes, demonstrating no cross-resistance with antimonials. CONCLUSIONS/SIGNIFICANCE: Taken together, these results suggest 2HF as a potential candidate for leishmaniasis chemotherapy for cutaneous leishmaniasis caused by both wild-type and antimony-resistant Leishmania species by oral administration. Furthermore, studies should be conducted to determine the ideal dose and therapeutic regimen.

2'-Hydroxyflavanone induced changes in the proteomic profile of breast cancer cells.[Pubmed:30248461]

J Proteomics. 2019 Feb 10;192:233-245.

In spite of rapid advances in understanding of signaling networks associated with the incidence and therapeutic-sensitivity, breast cancer (BC) still remains the most commonly diagnosed and prevalent cancer in women. Emergence of resistance to hormonal interventions in estrogen-receptor (ER) positive BC coupled to loss of ER expression and activation of ER-independent growth factor, heat-shock, MYC and WNT pathways along with distinct mechanisms of therapeutic-resistance in HER2 over-expressing and triple-negative subtypes of BC collectively necessitates deeper profiling of the mechanistic networks regulated by potential lead anticancer compounds intended for further development to target BC. A significant part of the search for novel lead anticancer compounds for BC has focused on phytochemicals including flavonoids found in citrus fruits, which have shown promising anticancer activity. Based on the initial studies which revealed the anticancer effect of 2HF in BC, we employed an advanced TMT 10plex labeled proteomic approach to characterize the changes in non-phosphorylated and phosphorylated proteomic profile of ER(+) MCF7, triple-negative MDA-MB231 and HER2(+) SKBR3 BC cells, and MCF10A normal breast epithelial cells. 2HF induced significant changes in the proteins responsible for BC incidence, metastases and therapeutic sensitivity in BC cells.

Metastasis of breast tumor cells to brain is suppressed by targeting RLIP alone and in combination with 2'-Hydroxyflavanone.[Pubmed:30223070]

Cancer Lett. 2018 Dec 1;438:144-153.

Brain metastasis is an important cause of morbidity and mortality in cancer-patients. Breast tumor cells frequently metastasize to brain and initiate severe therapeutic complications. In the present study, we evaluated the anti-metastatic effects of 2'-hydroxyflavanone (2HF) alone and in combination with RLIP targeted therapy in a novel murine model of breast tumor metastasis. The MDA-MB231Br (brain-seeking) breast cancer (BC) cells stably-transfected with luciferase were injected into the left-ventricle of NSG mouse heart and the migration of cells to brain was monitored using a non-invasive bioluminescent imaging system. To evaluate the tumor growth suppressive effects, mice were given 2HF (50mg/kg, b.w., alternate days orally), RLIP-antibody (Rab; 5mg/kg, b.w., weekly i.p.) or combination of 2HF+Rab starting day1 after intra-cardiac injection. Our results reveal that 2HF and Rab significantly prevented the metastasis of BC cells to brain. Further, mice treated with combination of 2HF+Rab exhibited no metastasis as compared to either or the single agent-treated mice. This study for the first time demonstrates the anti-metastatic effects of 2HF and RLIP-inhibition in-vivo in a novel breast tumor metastasis model and provides the rationale for further clinical investigation.

2'-Hydroxyflavanone inhibits in vitro and in vivo growth of breast cancer cells by targeting RLIP76.[Pubmed:30136444]

Mol Carcinog. 2018 Dec;57(12):1751-1762.

Consumption of citrus-fruits is associated with reduced incidence of breast cancer (BC), the most common cancer diagnosed in women across the globe. In this study, we investigated the anticancer potential of 2-Hydroxyflavanone (2HF) in BC. 2HF, a citrus-bioflavonoid, has demonstrated anticancer properties in various cancers, but its anticancer role in BC has not been well studied. We investigated the in vitro and in vivo growth inhibitory effects of 2HF in an array of BC lines and in xenograft mouse models of ER-positive and HER2-positive BC cells. Compared to control, 2HF treatment reduced cell viability and suppressed migratory and invasive potential of BC cells, while, no growth inhibitory effects were observed in non-tumorigenic breast epithelial cells. Further, 2HF inhibited the expression of RLIP76, a stress-defensive and anti-apoptotic protein, which is over-expressed in BC cells and simultaneously reduced proliferation of BC cells. Nude mice bearing MCF7 or SKBR3 BC cells xenografts treated with either 2HF or targeting RLIP76 by RLIP76-antisense or RLIP76-antibody treatment had significantly lower tumor-weight as compared to corresponding controls. In addition, Western-blotting and immunohistochemical analysis of tumor tissue from control and treatment group mice showed that 2HF decreased protein expression levels of RLIP76, and the decrease was similar to those seen following RLIP76-antisense treatment. Furthermore, 2HF decreased expression of Ki67, CD31, vimentin, inhibited phosphorylation of Akt and expression of survivin and Bcl2, and increased levels of Bax, E-cadherin, and cleaved-PARP. Therefore, our results indicate that 2HF may suppress BC growth in vitro and in vivo by targeting RLIP76, and may serve as a potential adjuvant treatment in BC patients.