2-methoxyE2 Abstracts 14


2-Methoxyestradiol-Mediated Induction of Frzb Contributes to Cell Death and Autophagy in MG63 Osteosarcoma Cells.
            (Bravo et al., 2016) Download
Osteosarcoma is a bone tumor that mainly affects children and adolescents. Although its pathogenesis is still not fully understood, activation of Wnt signaling has been implicated in the development and metastasis of osteosarcoma. In this report, we have investigated the effect of the anti-tumor compound, 2-methoxyestradiol (2-ME) on Wnt antagonist frizzled-related protein b (Frzb), also known as secreted frizzled-related protein (sFRP)3 in human osteosarcoma (MG63) cells. Our results show that 2-ME treatment induces Frzb gene promoter activity, and increases Frzb mRNA and protein levels in osteosarcoma cells. In addition, 2-ME treatment regulates downstream Wnt signaling, increasing the cytoplasmic levels of β-catenin, and blocking β-catenin-mediated Wnt activation in osteosarcoma cells. 2-ME-mediated induction of Frzb protein expression is specific to osteosarcoma cells, as it does not affect Frzb expression in normal primary human osteoblasts. Furthermore, 2-ME-induced apoptosis and autophagy are blocked in osteosarcoma cells transfected with Frzb siRNAs. Taken together, these studies demonstrate that Frzb protein plays an important role in 2-ME-mediated anti-tumor mechanisms in osteosarcoma cells. J. Cell. Biochem. 9999: 1-8, 2016. © 2016 Wiley Periodicals, Inc.

2-Methoxyestradiol protects against ischemia/reperfusion injury in alcoholic fatty liver by enhancing sirtuin 1-mediated autophagy.
            (Cho et al., 2017) Download
Alcoholic fatty liver (AFL) is susceptible to ischemia/reperfusion (I/R) injury, responding with inflammation and extensive hepatocellular damage. Autophagy maintains cellular homeostasis and regulates inflammation and lipid metabolism. 2-Methoxyestradiol (2-ME2), an endogenous metabolite of estradiol, exhibits antioxidant and anti-inflammatory properties. This study examined the cytoprotective mechanisms of 2-ME2 on hepatic I/R in AFL, focusing on autophagy signaling. C57BL/6 mice were fed an ethanol diet (ED) to induce AFL, or a control diet (CD) for 6weeks, and then subjected to 60min of ischemia and 5h of reperfusion. 2-ME2 (15mg/kg, i.p.) was administered 12h before ischemia and 10min before reperfusion, and sirtinol (sirtuin 1 (SIRT1) inhibitor, 10mg/kg, i.p.) was administered 30min before reperfusion. After reperfusion, ED animals showed higher serum aminotransferase activities and proinflammatory cytokine levels, and more severe histological changes compared with CD animals. These alterations were attenuated by 2-ME2. In the ED I/R group, autophagy and mitophagy were significantly impaired, as indicated by decreased hepatic levels of microtubule-associated protein 1 light chain 3 II and parkin protein expression, and increased p62 protein expression, which were attenuated by 2-ME2. The hepatic levels of Atg12-5 complex, Atg3, Atg7, lysosomal-associated membrane protein 2 and Rab7 protein expression significantly decreased in ED I/R animals, which were attenuated by 2-ME2. In the ED I/R group, the level of SIRT1 protein expression and its catalytic activity significantly decreased, which were attenuated by 2-ME2. Sirtinol reversed the stimulatory effect of 2-ME2 on autophagy. Our findings suggest that 2-ME2 ameliorates I/R-induced hepatocellular damage in AFL through activating SIRT1-mediated autophagy signaling.

Red Maca (Lepidium meyenii) did not affect cell viability despite increased androgen receptor and prostate-specific antigen gene expression in the human prostate cancer cell line LNCaP.
            (Díaz et al., 2016) Download
We examined whether aqueous extract of Lepidium meyenii (red Maca) could inhibit growth, potentiate apoptotic activity of two anticancer drugs Taxol and 2-methoxyestradiol (2ME) or change mRNA expression for the androgen target genes, androgen receptor (Ar) and prostate-specific antigen (Psa) in the human prostate cancer cell line LNCaP. Red Maca aqueous extract at 0, 10, 20, 40 or 80 μg/ml was added to LNCaP cells, and viability was evaluated by the MTS assay at 24 or 48 hr after treatment. Furthermore, LNCaP cells were treated with 80 μg/ml of red Maca plus Taxol or 2ME 5 μM and viability was assessed 48 hr later. Finally, LNCaP cells were treated with red Maca 0, 20, 40 or 80 μg/ml, and 12 hr later, mRNA level for Ar or Psa was assessed by real-time PCR. Treatment with red Maca did not affect viability of LNCaP cells. Apoptotic activity induced by Taxol and 2ME in LNCaP cells was not altered with red Maca treatment. Relative expression of the mRNA for Ar and Psa increased with red Maca 20 and 40 μg/ml, but not at 80 μg/ml. We conclude that red Maca aqueous extract does not have toxic effects, but stimulates androgen signalling in LNCaP cells.

The Bone Sparing Effects of 2-Methoxyestradiol Are Mediated via Estrogen Receptor-α in Male Mice.
            (Eriksson et al., 2016) Download
2-Methoxyestradiol (2ME2), a metabolite of 17β-estradiol (E2), exerts bone sparing effects in animal models. We hypothesized that the underlying mechanism is back conversion of 2ME2 to E2, which subsequently acts via estrogen receptor (ER)α. We measured serum E2 levels in orchidectomized wild-type (WT) mice treated with 2ME2 66.6 μg/d or placebo. In placebo-treated animals, E2 was below the detection limit. In 2ME2-treated mice, the serum E2 level was 4.97 ± 0.68 pg/mL. This corresponds to the level found in diesterus in cycling female mice. Next, we investigated bone parameters in orchidectomized WT and ERα knockout mice treated with 2ME2 or placebo for 35 days. 2ME2 (6.66 μg/d) preserved trabecular and cortical bone in WT mice. Trabecular volumetric-bone mineral density was 64 ± 20%, and trabecular bone volume/total volume was 60 ± 20% higher in the metaphyseal region of the femur in the 2ME2 group, compared with placebo (P < .01). Both trabecular number and trabecular thickness were increased (P < .01). Cortical bone mineral content in the diaphyseal region of the femur was 31 ± 3% higher in the 2ME2 group, compared with placebo (P < .001). This was due to larger cortical area (P < .001). Three-point bending showed an increased bone strength in WT 2ME2-treated animals compared with placebo (maximum load [Fmax] +19±5% in the 2ME2 group, P < .05). Importantly, no bone parameter was affected by 2ME2 treatment in ERα knockout mice. In conclusion, 2ME2 treatment of orchidectomized mice results in increased serum E2. ERα mediates the bone sparing effects of 2ME2. The likely mediator of this effect is E2 resulting from back conversion of 2ME2.

Inhibition of HIF-1α decreases expression of pro-inflammatory IL-6 and TNF-α in diabetic retinopathy.
            (Gao et al., 2016) Download
PURPOSE:  Recent studies demonstrate that pro-inflammatory cytokines (PICs, i.e. IL-1β, IL-6 and TNF-α) in retinal tissues are likely involved in the development of diabetic retinopathy (DR). In this report, we particularly examined contributions of hypoxia inducible factor subtype 1α (HIF-1α) to the expression of PICs and their receptors in diabetic retina. METHODS:  Streptozotocin (STZ) was systemically injected to induce hyperglycaemia in rats. ELISA and Western blot analysis were employed to determine the levels of HIF-1α and PICs as well as PIC receptors in retinal tissues of control rats and STZ rats. RESULTS:  The levels of retinal HIF-1α were significantly increased in STZ rats 4-10 weeks after induction of hyperglycaemia as compared with control animals. With increasing HIF-1α retinal PICs including IL-1β, IL-6 and TNF-α, their respective receptors, namely IL-1R, IL-6R and TNFR1, were also elevated in STZ rats. Moreover, inhibition of HIF-1α by injection of 2-methoxyestradiol (2-MET) significantly decreased the amplified expression IL-6, TNF-α, IL-6R and TNFR1 in diabetic retina, but did not modify IL-1β pathway. In addition, we examined protein expression of Caspase-3 indicating cell apoptosis in the retina of STZ rats after infusing 2-MET, demonstrating that 2-MET attenuated an increase in Caspase-3 evoked by STZ. CONCLUSION:  Hypoxia inducible factor subtype 1α (HIF-1α) activated in diabetic retina is likely to play a role in regulating pathophysiological process via IL-6 and TNF-α mechanism. This has pharmacological implications to target specific HIF-1α, IL-6 and TNF-α signalling pathway for dysfunction and vulnerability related to DR.


2-Methoxyestradiol Impacts on Amino Acids-mediated Metabolic Reprogramming in Osteosarcoma Cells by Interaction with NMDA Receptor.
            (Gorska-Ponikowska et al., 2017) Download
Deregulation of serine and glycine metabolism, have been identified to function as metabolic regulators in supporting tumor cell growth. The role of serine and glycine in regulation of cancer cell proliferation is complicated, dependent on concentrations of amino acids and tissue-specific. D-serine and glycine are coagonists of N-methyl-D-aspartate receptor subunit GRIN1. Importantly, NMDA receptors are widely expressed in cancer cells and play an important role in regulation of cell death, proliferation and metabolism of numerous malignancies. The aim of the present work was to associate the metabolism of glycine and D-serine with the anticancer activity of 2-methoxyestradiol. 2-methoxyestradiol is a potent anticancer agent but also a physiological 17β- estradiol metabolite. In the study we have chosen two malignant cell lines expressing functional GRIN1 receptors, i.e. osteosarcoma 143B and breast cancer MCF7. We used MTS assay, migration assay, flow cytometric analyses, western blotting and immunoprecipitation techniques as well as molecular modeling studies. We have demonstrated the extensive crosstalk between the deregulated metabolic network and cancer cell signaling. Herein, we observed an anticancer effect of high concentrations of glycine and D-serine in osteosarcoma cells. In contrast, the amino acids when used at low, physiological concentrations induced the proliferation and migration of osteosarcoma and breast cancer cells. Importantly, the pro-cancergogenic effects of both glycine and D-serine where abrogated by the usage of 2-methoxyestradiol at both physiological and pharmacological relevant concentrations. The obtained data confirmed that 2-methoxyestradiol may be a physiological anticancer molecule. This article is protected by copyright. All rights reserved.

Estrogen metabolites in human corpus luteum physiology: differential effects on angiogenic activity.
            (Henríquez et al., 2016) Download
OBJECTIVE:  To determine tissue concentrations of E2, estrone, P, and estrogens metabolites (EMs) 2-methoxyestradiol, 2-methoxyestrone, 4-hydroxyestrone, and 16-ketoestradiol in corpus luteum (CL) of different ages, and after hCG administration; and to examine the effects of EMs on vascular endothelial growth factor (VEGF) secretion and angiogenic activity released by cultured luteinizing granulosa cells in the presence and absence of hCG. DESIGN:  Experimental study. SETTING:  University. PATIENT(S):  Thirty-two healthy women of reproductive age. INTERVENTION(S):  Corpus luteum was collected at the time of minilaparotomy for tubal sterilization, at varying stages of the luteal phase (LP). Late-LP CL was collected 24 hours after IM administration of 10,000 IU hCG. Granulosa cells were isolated from follicular aspirates obtained from healthy women participating in our IVF program for male factor infertility. MAIN OUTCOMES MEASURE(S):  Estrogen metabolite concentrations were determined in CL tissue, and VEGF was assessed in conditioned medium. The angiogenic activity was analyzed by bioassay. RESULT(S):  Concentrations of EMs with proangiogenic activity (16-ketoestradiol and 4-hydroxyestrone) were higher in early and mid-LP CL vs. late-LP CL. These EMs and hCG increased VEGF production and angiogenic activity. Conversely, late-LP CL had significantly higher levels of 2-methoxyestrone and 2-methoxyestradiol, which have antiangiogenic activity. Administration of hCG reduced the production of these EMs. CONCLUSION(S):  Our findings suggest that the EMs are important paracrine modulators of CL function. Administration of hCG increases the production of EMs with proangiogenic activity and reduces the secretion of those EMs with antiangiogenic action, suggesting a novel mechanism by which the late-LP CL is rescued in conception cycles.

GSNO promotes functional recovery in experimental TBI by stabilizing HIF-1α.
            (Khan et al., 2016) Download
Traumatic brain injury (TBI) causes sustained disability due to compromised neurorepair mechanisms. Crucial to neurorepair and functional recovery following both TBI and stroke is hypoxia-inducible factor-1 alpha (HIF-1α). Based on reports that HIF-1α could be stabilized via S-nitrosylation, we tested the hypothesis that the S-nitrosylating agent S-nitrosoglutathione (GSNO) would stabilize HIF-1α, thereby stimulating neurorepair mechanisms and aiding in functional recovery. TBI was induced by controlled cortical impact (CCI) in adult rats. GSNO (0.05mg/kg) was administered at two hours after CCI. The treatment was repeated daily until the 14th day after CCI. Functional recovery was assessed by motor and cognitive functions, and the recovery was compared with the expression of HIF-1α. The mechanisms of GSNO-mediated S-nitrosylation of HIF-1α were determined using brain endothelial cells. While non-treated TBI animals showed sustained neurobehavioral deficits, GSNO treatment of TBI improved neurobehavioral functions. GSNO also increased the expression of HIF-1α and VEGF. The beneficial effects of GSNO on neurobehavioral functions in TBI animals were blocked by treatment with the HIF-1α inhibitor 2-methoxyestradiol (2-ME). The stimulatory effect of GSNO on VEGF was reversed not only by 2-ME but also by the denitrosylating agent dithiothreitol, confirming our hypothesis that GSNO's benefits are mediated by the stabilization of HIF-1α via S-nitrosylation. GSNO's S-nitrosylation of HIF-1α was further confirmed using a biotin switch assay in endothelial cells. The data provide evidence that GSNO treatment of TBI aids functional recovery through stabilizing HIF-1α via S-nitrosylation. GSNO is a natural component of the human brain/body, and its exogenous administration has not shown adverse effects in humans. Therefore, the translational potential of GSNO therapy in TBI is high.


Photoactivated hypericin increases the expression of SOD-2 and makes MCF-7 cells resistant to photodynamic therapy.
            (Kimáková et al., 2017) Download
Photoactivated hypericin increased production of reactive oxygen species in human breast adenocarcinoma MCF-7 as well as in MDA-MB-231 cells 1h after photodynamic therapy. On the other hand, reactive oxygen species dropped 3h after photodynamic therapy with hypericin, but only in MCF-7 cells, whereas in MDA-MB-231 cells remained elevated. The difference in the dynamics of reactive oxygen species after hypericin activation was related to increased activity of SOD-2 in MCF-7 cells compared to MDA-MB-231 cells. Indeed, photodynamic therapy with hypericin significantly increased SOD-2 activity in MCF-7 cells, but only slightly in MDA-MB-231 cells. In this regard, SOD-2 activity correlated well with enhanced both mRNA expression as well as SOD-2 protein level in MCF-7 cells. The role of SOD-2 in the resistance of MCF-7 cells to photodynamic therapy with hypericin was monitored using SOD-2 inhibitor - 2-methoxyestradiol. Interestingly, the combination of photodynamic therapy with hypericin and methoxyestradiol sensitized MCF-7 cells to photodynamic therapy and significantly reduced its clonogenic ability. Furthermore, methoxyestradiol potentiated the activation of caspase 3/7 and apoptosis induced by photodynamic therapy with hypericin.

2-methoxyestradiol inhibits intracerebral hemorrhage-induced angiogenesis in rats.
            (Li et al., 2016) Download
AIM:  Angiogenesis occurs after intracerebral hemorrhage (ICH). Hypoxia-inducible factor-1α (HIF-1α) is a critical regulator of angiogenesis; however, its role in the central nervous system remains controversial. 2-Methoxyestradiol (2ME2), a natural metabolite of estrogen, is known to inhibit HIF-1α. In the present study, we investigated the effect of 2ME2 in a rat model of ICH-induced angiogenesis. MATERIAL AND METHODS:  Sprague-Dawley male rats were randomly divided into 5 groups: Sham operated group; ICH; ICH+2ME2; and ICH+Vehicle groups. ICH model was induced by stereotactic injection of collagenase type VII into right globus pallidus. 2ME2 or vehicle (10 % dimethyl sulfoxide) was administered intraperitoneally 10 min after ICH. Angiogenesis and expression of HIF-1α was evaluated by immunohistochemistry, quantitative real time reverse transcription polymerase chain reaction and western blot, respectively. RESULTS:  Proliferating cell nuclear antigen (PCNA)-labeled nuclei were detected in cerebral endothelial cells (ECs) around the hematoma; the labeling peaked at 14 days post-ICH. HIF-1α - immunoreactive microvessels with dilated outline were detected in the perihematomal tissues; the vessels extended into the clot from the surrounding tissues from day 7 onwards. HIF-1α protein levels increased, while no change was observed in HIF-1α mRNA expression after ICH. 2ME2 decreased the PCNA-labeled nuclei in cerebral ECs and down-regulated the expression of HIF-1α protein as well, while it had little effect on the mRNA expression of HIF-1α. CONCLUSION:  These findings suggest that the HIF-1α inhibitor, 2ME2, inhibited post-ICH angiogenesis by suppressing HIF-1α expression, thus exerting detrimental effects in ICH.

Inotropic support against early brain injury improves cerebral hypoperfusion and outcomes in a murine model of subarachnoid hemorrhage.
            (Mutoh et al., 2016) Download
Early brain injury/ischemia is a recent therapeutic target that contributes to triggering delayed cerebral ischemia (DCI) in the setting of subarachnoid hemorrhage (SAH). This study aimed to determine the role of dobutamine for inotropic cardiac support in improving cerebral blood flow (CBF) and outcomes after experimental SAH, mediated by hypoxia-inducible factor (HIF). Thirty-one mice were subjected to SAH by endovascular perforation, and assigned to either 2% isoflurane postconditioning performed between 1 and 2.5h after SAH induction or concomitant intravenous dobutamine infusion (15μg/kg/min) with or without HIF inhibitor 2-methoxyestradiol (2ME2) (10mg/kg) administered intraperitoneally. Neurobehavioral function was assessed daily by neurological scores and open field testing. DCI was defined 3days later by detecting a new infarction on MRI. Global CBF depression was notable early after SAH, but dobutamine showed significant improvement in CBF, lower incidence of DCI, and better recovery of neuroscores and open field test variables compared with isoflurane postconditioning (P<0.05). CBF over the entire brain on day 1 predicted DCI with a cut-off of 36.5mL/100g/min (80% specificity and 67% sensitivity), with a better area under the curve (0.83 versus 0.75) than the hemispheric CBF measured on the perforated side. The dobutamine-mediated outcomes were attenuated (P<0.05) by 2ME2 pretreatment. The data suggest that cardiac support with dobutamine improves global CBF depression induced by early brain injury, leading to reduced prevalence of DCI and better functional outcomes after experimental SAH, in which HIF may be acting as a critical mediator.

Influence of surface passivation of 2-Methoxyestradiol loaded PLGA nanoparticles on cellular interactions, pharmacokinetics and tumour accumulation.
            (Pillai et al., 2016) Download
In the present work, 2-Methoxyestradiol [2ME2] loaded PLGA nanoparticles [NPs] were stabilized with Casein or poly(ethylene glycol) [PEG] and evaluated for its cellular interactions, pharmacokinetics and tumour accumulation. Surface stabilized PLGA nanoparticles prepared through a modified emulsion route possessed similar size, surface charge, drug loading and release characteristics. Particle-cell interactions as well as the anti-angiogenesis activity were similar for both nanoformulations in vitro. However, in vivo pharmacokinetics and tumour accumulation of the drug were substantially improved for the PEGylated nanoformulation. Reduced protein binding was observed for PEG stabilized PLGA NPs. Thus, it was demonstrated that nanoencapsulation of 2-ME2 within PEGylated PLGA nanocarrier could improve its half-life and plasma concentration and thereby increase the tumour accumulation.

Cytochrome P450 1A2 Metabolizes 17β-Estradiol to Suppress Hepatocellular Carcinoma.
            (Ren et al., 2016) Download
Hepatocellular carcinoma (HCC) occurs more frequently in men than in women. It is commonly agreed that estrogen plays important roles in suppressing HCC development, however, the underlying mechanism remains largely unknown. Since estrogen is mainly metabolized in liver and its metabolites affect cell proliferation, we sought to investigate if the liver-specific cytochrome P450 1A2 (CYP1A2) mediated the inhibitory effect of estrogen on HCC. In this study, the expression of estrogen-metabolizing enzyme CYP1A2 was determined in HCC tissues and cell lines. Cell proliferation and apoptosis were assessed in cells with or without CYP1A2 overexpression. The levels of 17β-estradiol (E2) and its metabolite 2-methoxyestradiol (2-ME) were determined. A xenograft tumor model in mice was established to confirm the findings. It was found that CYP1A2 expression was greatly repressed in HCC. E2 suppressed HCC cell proliferation and xenograft tumor development by inducing apoptosis. The inhibitory effect was significantly enhanced in cells with CYP1A2 overexpression, which effectively conversed E2 to the cytotoxic 2-ME. E2 in combination with sorafenib showed an additive effect on HCC. The anti-HCC effect of E2 was not associated with estrogen receptors ERα and ERβ as well as tumor suppressor P53 but enhanced by the approved anti-HCC drug sorafenib. In addition, HDAC inhibitors greatly induced CYP1A2 promoter activities in cancer cells, especially liver cancer cells, but not in non-tumorigenic cells. Collectively, CYP1A2 metabolizes E2 to generate the potent anti-tumor agent 2-ME in HCC. The reduction of CYP1A2 significantly disrupts this metabolic pathway, contributing the progression and growth of HCC and the gender disparity of this malignancy.

Targeting SOD1 induces synthetic lethal killing in BLM- and CHEK2-deficient colorectal cancer cells.
            (Sajesh and McManus, 2015) Download
Cancer is a major cause of death throughout the world, and there is a large need for better and more personalized approaches to combat the disease. Over the past decade, synthetic lethal approaches have been developed that are designed to exploit the aberrant molecular origins (i.e. defective genes) that underlie tumorigenesis. BLM and CHEK2 are two evolutionarily conserved genes that are somatically altered in a number of tumor types. Both proteins normally function in preserving genome stability through facilitating the accurate repair of DNA double strand breaks. Thus, uncovering synthetic lethal interactors of BLM and CHEK2 will identify novel candidate drug targets and lead chemical compounds. Here we identify an evolutionarily conserved synthetic lethal interaction between SOD1 and both BLM and CHEK2 in two distinct cell models. Using quantitative imaging microscopy, real-time cellular analyses, colony formation and tumor spheroid models we show that SOD1 silencing and inhibition (ATTM and LCS-1 treatments), or the induction of reactive oxygen species (2ME2 treatment) induces selective killing within BLM- and CHEK2-deficient cells relative to controls. We further show that increases in reactive oxygen species follow SOD1 silencing and inhibition that are associated with the persistence of DNA double strand breaks, and increases in apoptosis. Collectively, these data identify SOD1 as a novel candidate drug target in BLM and CHEK2 cancer contexts, and further suggest that 2ME2, ATTM and LCS-1 are lead therapeutic compounds warranting further pre-clinical study.

CYP3A7*1C allele is associated with reduced levels of 2-hydroxylation pathway oestrogen metabolites.
            (Sood et al., 2017) Download
BACKGROUND:  Endogenous sex hormones are well-established risk factors for breast cancer; the contribution of specific oestrogen metabolites (EMs) and/or ratios of specific EMs is less clear. We have previously identified a CYP3A7*1C allele that is associated with lower urinary oestrone (E1) levels in premenopausal women. The purpose of this analysis was to determine whether this allele was associated with specific pathway EMs. METHODS:  We measured successfully 12 EMs in mid-follicular phase urine samples from 30 CYP3A7*1C carriers and 30 non-carriers using HPLC-MS/MS. RESULTS:  In addition to having lower urinary E1 levels, CYP3A7*1C carriers had significantly lower levels of four of the 2-hydroxylation pathway EMs that we measured (2-hydroxyestrone, P=1.1 × 10(-12); 2-hydroxyestradiol, P=2.7 × 10(-7); 2-methoxyestrone, P=1.9 × 10(-12); and 2-methoxyestradiol, P=0.0009). By contrast, 16α-hydroxylation pathway EMs were slightly higher in carriers and significantly so for 17-epiestriol (P=0.002). CONCLUSIONS:  The CYP3A7*1C allele is associated with a lower urinary E1 levels, a more pronounced reduction in 2-hydroxylation pathway EMs and a lower ratio of 2-hydroxylation:16α-hydroxylation EMs in premenopausal women. To further characterise the association between parent oestrogens, EMs and subsequent risk of breast cancer, characterisation of additional genetic variants that influence oestrogen metabolism and large prospective studies of a broad spectrum of EMs will be required.


2-Methoxyestradiol Alleviates Experimental Autoimmune Uveitis by Inhibiting Lymphocytes Proliferation and T Cell Differentiation.
            (Xu et al., 2016) Download
Purpose. To investigate the effect of 2-Methoxyestradiol (2ME2) on experimental autoimmune uveitis (EAU) and the mechanism. Method. C57BL/6 male mice were used to establish the EAU model. 2ME2 was abdominal administrated in D0-D13, D0-D6, and D7-D13 and control group was given vehicle from D0-D13. At D14, pathological severity was scored. Lymphocyte reaction was measured using MTT assay. T cell differentiation in draining lymph nodes and eye-infiltrating cells was tested by flow cytometry. Proinflammatory cytokines production from lymphocytes was determined by ELISA. Result. The disease scores from 2ME2 D0-D13, 2ME2 D0-D6, 2ME2 D7-D13, and vehicle groups were 0.20 ± 0.12, 1.42 ± 0.24, 2.25 ± 0.32, and 2.42 ± 0.24. Cells from all 2ME2 treated groups responded weaker than control (p < 0.05). The inhibitory effect of 2ME2 on lymphocyte proliferation attenuated from 2ME2 D0-D13 to 2ME2 D0-D6 and to 2ME2 D7-D13 groups (p < 0.05). 2ME2 treated mice developed fewer Th1 and Th17 cells both in draining lymph nodes and in eyes than control (p < 0.05). Lymphocytes from 2ME2 group secreted less IFN-γ and IL-17A than those from control (p < 0.05). Conclusion. 2ME2 ameliorated EAU progression and presented a better effect at priming phase. The possible mechanism could be the inhibitory impact on IRBP specific lymphocyte proliferation and Th1 and Th17 cell differentiation.

2-Methoxyestradiol protects against IgG immune complex-induced acute lung injury by blocking NF-κB and CCAAT/enhancer-binding protein β activities.
            (Yan et al., 2017) Download
Increasing evidences indicate that 2-Methoxyestradiol (2ME2) plays an essential role in protecting against inflammatory responses. However, its effect on IgG immune complex (IC)-induced acute lung injury (ALI) remains enigmatic. In the study, by using i.p. administration of 2ME2, we evaluated its influence on IgG IC-induced pulmonary injury in mice. We found that during IgG IC-induced ALI, mice treated by 2ME2 displayed a substantial decrease in vascular permeability and neutrophil influx (represented by myeloperoxidase activity) when compared with their counterparts receiving vehicle treatment. Furthermore, 2ME2 treatment significantly decreased pro-inflammatory mediator production and inflammatory cell, especially neutrophil accumulation in bronchoalveolar lavage fluids (BALFs) upon IgG IC stimulation. In vitro, IgG IC-triggered inflammatory mediator production was markedly down-regulated by 2ME2 in macrophages. Moreover, we verified that the activation of the transcription factors, NF-κB and CCAAT/enhancer-binding protein (C/EBP) β, were inhibited by 2ME2 in IgG IC-challenged macrophages. We demonstrated that alleviation of NF-κB-dependent transcription might be associated with reduced phosphorylation of NF-κB p65, and reduction of C/EBP activation was directly linked to its expression. In addition, we discovered that IgG IC-stimulated phosphorylation of both p38 MAPK and ERK1/2 was alleviated by 2ME2. These data indicated a novel strategy for blockade of IgG IC-induced inflammatory activities.



Bravo, D, et al. (2016), ‘2-Methoxyestradiol-Mediated Induction of Frzb Contributes to Cell Death and Autophagy in MG63 Osteosarcoma Cells.’, J Cell Biochem, PubMed: 27883247
Cho, HI, MJ Seo, and SM Lee (2017), ‘2-Methoxyestradiol protects against ischemia/reperfusion injury in alcoholic fatty liver by enhancing sirtuin 1-mediated autophagy.’, Biochem Pharmacol, PubMed: 28213273
Díaz, P, H Cardenas, and PA Orihuela (2016), ‘Red Maca (Lepidium meyenii) did not affect cell viability despite increased androgen receptor and prostate-specific antigen gene expression in the human prostate cancer cell line LNCaP.’, Andrologia, 48 (8), 922-26. PubMed: 27681649
Eriksson, AL, et al. (2016), ‘The Bone Sparing Effects of 2-Methoxyestradiol Are Mediated via Estrogen Receptor-α in Male Mice.’, Endocrinology, 157 (11), 4200-5. PubMed: 27631553
Gao, X, et al. (2016), ‘Inhibition of HIF-1α decreases expression of pro-inflammatory IL-6 and TNF-α in diabetic retinopathy.’, Acta Ophthalmol, PubMed: 27288252
Gorska-Ponikowska, M, et al. (2017), ‘2-Methoxyestradiol Impacts on Amino Acids-mediated Metabolic Reprogramming in Osteosarcoma Cells by Interaction with NMDA Receptor.’, J Cell Physiol, PubMed: 28262924
Henríquez, S, et al. (2016), ‘Estrogen metabolites in human corpus luteum physiology: differential effects on angiogenic activity.’, Fertil Steril, PubMed: 26994433
Khan, M, et al. (2016), ‘GSNO promotes functional recovery in experimental TBI by stabilizing HIF-1α.’, Behav Brain Res, PubMed: 27780722
Kimáková, P, et al. (2017), ‘Photoactivated hypericin increases the expression of SOD-2 and makes MCF-7 cells resistant to photodynamic therapy.’, Biomed Pharmacother, 85 749-55. PubMed: 27923686
Li, HT, et al. (2016), ‘2-methoxyestradiol inhibits intracerebral hemorrhage-induced angiogenesis in rats.’, Turk Neurosurg, PubMed: 27943229
Mutoh, T, et al. (2016), ‘Inotropic support against early brain injury improves cerebral hypoperfusion and outcomes in a murine model of subarachnoid hemorrhage.’, Brain Res Bull, PubMed: 28017781
Pillai, GJ, et al. (2016), ‘Influence of surface passivation of 2-Methoxyestradiol loaded PLGA nanoparticles on cellular interactions, pharmacokinetics and tumour accumulation.’, Colloids Surf B Biointerfaces, 150 242-49. PubMed: 27923186
Ren, J, et al. (2016), ‘Cytochrome P450 1A2 Metabolizes 17β-Estradiol to Suppress Hepatocellular Carcinoma.’, PLoS One, 11 (4), e0153863. PubMed: 27093553
Sajesh, BV and KJ McManus (2015), ‘Targeting SOD1 induces synthetic lethal killing in BLM- and CHEK2-deficient colorectal cancer cells.’, Oncotarget, 6 (29), 27907-22. PubMed: 26318585
Sood, D, et al. (2017), ‘CYP3A7*1C allele is associated with reduced levels of 2-hydroxylation pathway oestrogen metabolites.’, Br J Cancer, 116 (3), 382-88. PubMed: 28072767
Xu, L, et al. (2016), ‘2-Methoxyestradiol Alleviates Experimental Autoimmune Uveitis by Inhibiting Lymphocytes Proliferation and T Cell Differentiation.’, Biomed Res Int, 2016 7948345. PubMed: 27243036
Yan, C, et al. (2017), ‘2-Methoxyestradiol protects against IgG immune complex-induced acute lung injury by blocking NF-κB and CCAAT/enhancer-binding protein β activities.’, Mol Immunol, 85 89-99. PubMed: 28214650