An integrated network pharmacology and molecular docking approach to reveal the role of Arctigenin against Cutibacterium acnes-induced skin inflammation by targeting the CYP19A1.

Acne caused by inflammation of hair follicles and sebaceous glands is a common chronic skin disease. Arctigenin (ATG) is an extract of Arctium lappa L., which has significant anti-inflammatory effects. However, the effect and mechanism of ATG in cutaneous inflammation mediated by Cutibacterium acnes (C. acnes) has not been fully evaluated. The purpose of this study was to explore the effect and potential mechanism of ATG in the treatment of acne through network pharmacology and experimental confirmation. An acne model was established by injected live C. acnes into living mice and treated with ATG. Our data showed that ATG effectively improved acne induced by live C. acnes, which was confirmed by determining ear swelling rate, estradiol concentration and hematoxylin and eosin (H&E) staining. In addition, ATG inhibited the NLRP3 inflammasome signaling pathway in mice ear tissues and reduced the secretion of pro-inflammatory cytokines IL-1ß to relieve inflammation. The results of network pharmacology and molecular docking confirmed that ATG can regulate 17ß-Estradiol (E2) levels through targeted to CYP19A1, and finally inhibited skin inflammation. Taken together, our results confirmed that ATG regulated E2 secretion by targeting CYP19A1, thereby inhibiting the NLRP3 inflammasome signaling pathway and improving inflammation levels in acne mice. This study provides a basis for the feasibility of ATG in treating acne in clinical practice.

Unique features of KGN granulosa-like tumour cells in the regulation of steroidogenic and antioxidant genes.

The ovarian KGN granulosa-like tumour cell line is commonly used as a model for human granulosa cells, especially since it produces steroid hormones. To explore this further, we identified genes that were differentially expressed by KGN cells compared to primary human granulosa cells using three public RNA sequence datasets. Of significance, we identified that the expression of the antioxidant gene TXNRD1 (thioredoxin reductase 1) was extremely high in KGN cells. This is ominous since cytochrome P450 enzymes leak electrons and produce reactive oxygen species during the biosynthesis of steroid hormones. Gene Ontology (GO) analysis identified steroid biosynthetic and cholesterol metabolic processes were more active in primary granulosa cells, whilst in KGN cells, DNA processing, chromosome segregation and kinetochore pathways were more prominent. Expression of cytochrome P450 cholesterol side-chain cleavage (CYP11A1) and cytochrome P450 aromatase (CYP19A1), which are important for the biosynthesis of the steroid hormones progesterone and oestrogen, plus their electron transport chain members (FDXR, FDX1, POR) were measured in cultured KGN cells. KGN cells were treated with 1 mM dibutyryl cAMP (dbcAMP) or 10 µM forskolin, with or without siRNA knockdown of TXNRD1. We also examined expression of antioxidant genes, H2O2 production by Amplex Red assay and DNA damage by γH2Ax staining. Significant increases in CYP11A1 and CYP19A1 were observed by either dbcAMP or forskolin treatments. However, no significant changes in H2O2 levels or DNA damage were found. Knockdown of expression of TXNRD1 by siRNA blocked the stimulation of expression of CYP11A1 and CYP19A1 by dbcAMP. Thus, with TXNRD1 playing such a pivotal role in steroidogenesis in the KGN cells and it being so highly overexpressed, we conclude that KGN cells might not be the most appropriate model of primary granulosa cells for studying the interplay between ovarian steroidogenesis, reactive oxygen species and antioxidants.

Male autism spectrum disorder is linked to brain aromatase disruption by prenatal BPA in multimodal investigations and 10HDA ameliorates the related mouse phenotype.

Male sex, early life chemical exposure and the brain aromatase enzyme have been implicated in autism spectrum disorder (ASD). In the Barwon Infant Study birth cohort (n = 1074), higher prenatal maternal bisphenol A (BPA) levels are associated with higher ASD symptoms at age 2 and diagnosis at age 9 only in males with low aromatase genetic pathway activity scores. Higher prenatal BPA levels are predictive of higher cord blood methylation across the CYP19A1 brain promoter I.f region (P = 0.009) and aromatase gene methylation mediates (P = 0.01) the link between higher prenatal BPA and brain-derived neurotrophic factor methylation, with independent cohort replication. BPA suppressed aromatase expression in vitro and in vivo. Male mice exposed to mid-gestation BPA or with aromatase knockout have ASD-like behaviors with structural and functional brain changes. 10-hydroxy-2-decenoic acid (10HDA), an estrogenic fatty acid alleviated these features and reversed detrimental neurodevelopmental gene expression. Here we demonstrate that prenatal BPA exposure is associated with impaired brain aromatase function and ASD-related behaviors and brain abnormalities in males that may be reversible through postnatal 10HDA intervention.

Expression levels of the selenium-uptake receptor LRP8, the antioxidant selenoprotein GPX1 and steroidogenic enzymes correlate in granulosa cells.

Abstract: Reactive oxygen species (ROS) are a by-product of the activity of cytochrome P450 steroidogenic enzymes. Antioxidant enzymes protect against ROS damage. To identify if any particular antioxidant enzyme is used to protect against ROS produced by granulosa cells as follicles enlarge and produce oestradiol, we measured in the bovine granulosa cells the expression of two steroidogenic enzymes (CYP11A1, CYP19A1), important for progesterone and oestradiol production. We also measured the expression of the members (FDXR, FDX1, POR) of their electron transport chains (ETC). We measured antioxidant enzymes (GPXs 1-8, CAT, SODs 1 and 2, PRDXs 1-6, GSR, TXN, TXNRDs 1-3). Since selenium is an active component of GPXs, the selenium-uptake receptors (LRPs 2 and 8) were measured. Only the selenium-dependent GPX1 showed the same increase in expression as the steroidogenic enzymes did with increasing follicle size. GPX4 and PRDX2/6 decreased with follicle size, whereas SOD1/2, CAT, GSR, and TXNRD3 were lowest at the intermediate sizes. The other antioxidant enzymes were unchanged or expressed at low levels. The expression of the selenium-uptake receptor LRP8 also increased significantly with follicle size. Correlation analysis revealed statistically significant and strongly positive correlations of the steroidogenic enzymes and their ETCs with both GPX1 and LRP8. These results demonstrate a relationship between the expression of genes involved in steroidogenesis and selenium-containing antioxidant defence mechanisms. They suggest that during the late stages of folliculogenesis, granulosa cells are dependent on sufficient expression of GPX1 and the selenium transporter LRP8 to counteract increasing ROS levels caused by the production of steroid hormones. Lay summary: In the ovary, eggs are housed in follicles which contain the cells that produce oestrogen in the days leading up to ovulation of the egg. Oestrogen is produced by the action of enzymes. However, some of these enzymes also produce by-products called reactive oxygen species (ROS). These are harmful to eggs. Fortunately, cells have protective antioxidant enzymes that can neutralise ROS. This study was interested in which particular antioxidant enzyme(s) might be involved in neutralising the ROS in follicle cells. It was found that only one antioxidant enzyme, GPX1, appeared to be co-regulated with the enzymes that produce oestrogen and progesterone in the follicular cells. GPX1 contains the essential mineral selenium. In summary, this study has identified which antioxidant appears to be involved in neutralising ROS in the days leading to ovulation. It highlights the importance of selenium in the diet.

DMF-DMA catalyzed Synthesis, molecular docking, in-vitro, in-silico design, and binding free energy studies of novel thiohydantoin derivatives as antioxidant and antiproliferative agents targeting EGFR tyrosine kinase and aromatase cytochrome P450 enzyme.

A set of novels 2-thiohydantoin derivatives were synthesized and enaminone function was discussed at position 5 using DMFDMA catalyst which result in formation of pyrazole, isoxazole, benzoxazepine by using reagents such as hydrazine, hydroxylamine and 2-aminothiophenol. These newly synthesized compounds were evaluated for their antioxidant and antiproliferative activity. In vitro studies on the effect of 2-thiohydantoin on scavenging 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•) confirmed the free radical scavenging and antioxidant activity of 2-thiohydantoin. The synthesized compounds show significant antioxidant activity. The in vitro antitumor activity of 2-thiohydantoin on MCF7 (breast) and PC3 cells (prostate) was evaluated using MTT assay. Some of the synthesized compounds show significant to moderate antiproliferative properties compared to reference drug erlotinib. Among all, compound 4a exhibit potent antitumor properties against MCF7 and PC3 cancer cell lines with IC50 = 2.53 ± 0.09 /ml & with IC50 = 3.25 ± 0.12 µg/ml respectively and has potent antioxidant activity with IC50 = 10.04 ± 0.49 µg/ml.

Inositol Restores Appropriate Steroidogenesis in PCOS Ovaries Both In Vitro and In Vivo Experimental Mouse Models.

Androgen excess is a key feature of several clinical phenotypes of polycystic ovary syndrome (PCOS). However, the presence of FSH receptor (FSHR) and aromatase (CYP19A1) activity responses to physiological endocrine stimuli play a critical role in the pathogenesis of PCOS. Preliminary data suggest that myo-Inositol (myo-Ins) and D-Chiro-Inositol (D-Chiro-Ins) may reactivate CYP19A1 activity. We investigated the steroidogenic pathway of Theca (TCs) and Granulosa cells (GCs) in an experimental model of murine PCOS induced in CD1 mice exposed for 10 weeks to a continuous light regimen. The effect of treatment with different combinations of myo-Ins and D-Chiro-Ins on the expression of Fshr, androgenic, and estrogenic enzymes was analyzed by real-time PCR in isolated TCs and GCs and in ovaries isolated from healthy and PCOS mice. Myo-Ins and D-Chiro-Ins, at a ratio of 40:1 at pharmacological and physiological concentrations, positively modulate the steroidogenic activity of TCs and the expression of Cyp19a1 and Fshr in GCs. Moreover, in vivo, inositols (40:1 ratio) significantly increase Cyp19a1 and Fshr. These changes in gene expression are mirrored by modifications in hormone levels in the serum of treated animals. Myo-Ins and D-Chiro-Ins in the 40:1 formula efficiently rescued PCOS features by up-regulating aromatase and FSHR levels while down-regulating androgen excesses produced by TCs.

Hsa_circ_0043532 contributes to PCOS through upregulation of CYP19A1 by acting as a ceRNA for hsa-miR-1270.

BACKGROUND: Polycystic ovarian syndrome (PCOS) accounts for about 75% of anovulatory infertility. The cause of PCOS is not clear. CircRNAs acting as miRNA sponges mediate the post-transcriptional regulation of multiple genes. CYP19A1 is a limiting enzyme in the ovarian steroidogenesis pathway. However, the mechanism of circRNAs regulating granulosa cell (GC) estradiol secretion in PCOS remains to be elucidated. METHODS: Bioinformatics was used to predict the potential target miRNAs of circ_0043532 and target genes of miR-1270. Target miRNAs and mRNA expression were verified by qRT-PCR in GCs from 45 women with PCOS and 65 non-PCOS. Western blot, ELISA and dual-luciferase reporter assays were applied to confirm the substrate of miR-1270. RESULTS: Circ_0043532 and CYP19A1 were significant up-regulation in GCs from patients with PCOS. The predicted target miRNAs of circ_0053432, miR-1270, miR-576-5p, miR-421 and miR-142-5p, were notably decreased in GCs from patients with PCOS. Mechanistic experiments showed that circ_0043532 specifically binds to miR-1270. MiR-1270 was negatively regulated by circ_0043532. Concomitantly, miR-1270 inhibited CYP19A1 expression and estradiol production, which could be reversed by circ_0043532 over-expression. CONCLUSION: We identified that circ_0043532/miR-1270/CYP19A1 axis contributes to the aberrant steroidogenesis of GCs from patients with PCOS. This study broadens the spectrum of pathogenic factors of PCOS, and circ_0043532 might be a potential therapeutic target for PCOS.

Smad4 and FoxH1 potentially interact to regulate cyp19a1a promoter in the ovary of ricefield eel (Monopterus albus).

BACKGROUND: Cyp19a1a is a key enzyme in the pathway that converts androgens into estrogen and is regulated by TGF-ß signaling. Smad4 and FoxH1 are downstream effectors of TGF-ß signaling and may play important roles in ovarian development in M. albus. METHODS: We investigated the expression pattern of the Smad4 and FoxH1 using qRT‒PCR and immunofluorescence, then tested the changes of smad4 and foxh1 by qRT‒PCR after ovary incubation with FSH in vitro, and analysed the regulation of cyp19a1a transcription by Smad4 and FoxH1 by dual-luciferase reporter assays. RESULTS: We found that Smad4 encoded a putative protein of 449 amino acids and harbored the three conserved domains typical of this protein family. Smad4 and foxh1 exhibited similar expression patterns during ovarian development and after FSH incubation, with Pearson's coefficients of 0.873 and 0.63-0.81, respectively. Furthermore, Smad4, FoxH1 and Cyp19a1a colocalized in the granulosa cells and theca cells of ovaries during the mid-to-late vitellogenic stage. Smad4 repressed cyp19a1a activity via SBE1 (- 1372/-1364) and SBE2 (- 415/-407) in the cyp19a1a promoter, whereas mutating SBE1 or SBE2 restored cyp19a1a promoter activity. Co-overexpression of Smad4 and FoxH1 significantly reduced cyp19a1a promoter activity. CONCLUSIONS: This study provides new insights into the potential functions of transcription factors Smad4 and FoxH1 in ovarian development and the transcriptional regulation mechanism of cyp19a1a in M. albus, which will reveal Smad4/FoxH1-mediated TGF-ß signaling in reproduction and the regulation of the cyp19a1a. Aromatase, encoded by cyp19a1a, is involved in ovarian development and plays an important role in the quality of eggs, as well the sex ratio, of the teleost fish, M. albus. The research on the transcriptional regulation of cyp19a1a has contributed to the understanding of its role in ovarian development. In previous study, it was shown that FoxH1 inhibits cyp19a1a transcription. In the present study, Smad4 was confirmed as a cyp19a1a transcriptional repressor and Smad4 may also coordinate with FoxH1 to repress cyp19a1a transcription. At present, we provide a new perspective for the transcriptional regulation of cyp19a1a by transcription factors Smad4 and FoxH1 in teleost fish ovary. In the future, the regulatory networks of Smad4 and FoxH1 will be further studied and the gene editing technology will be applied to screen specific regulatory factors of cyp191a1a gene, so as to alter the female cycle and modulate the sex ratio of the eggs production.

Diagnostic Value of Autoantibodies against Steroidogenic Enzymes and Hormones in Infertile Women with Premature Ovarian Insufficiency.

The objective of the study was to evaluate the profile and diagnostic significance of serum autoantibodies in infertile patients with premature ovarian insufficiency (POI). The pilot study included 26 patients of reproductive age with POI and diminished ovarian reserve who received complex treatment using new surgical technologies (Group 1) and 18 patients without POI (Group 2). The profile of serum autoantibodies, including anti-ovarian antibodies, antibodies against thyroid peroxidase (TPO), steroidogenic enzymes, and steroid and gonadotropic hormones, was studied using modified ELISAs and human recombinant steroidogenic enzymes (CYP11A1, CYP19A1, CYP21A2). Patients in Group 1 had higher levels of IgG autoantibodies against steroidogenic enzymes, estradiol, progesterone, and TPO than those in Group 2. Tests for IgG antibodies against CYP11A1, CYP19A1, and CYP21A2 exhibited high sensitivity (65.4-76.9%), specificity (83.3-89.9%), and AUC values (0.842-0.910) for POI, the highest in the first test. Three-antibodies panel screening showed higher diagnostic accuracy (84.1% versus 75-79.6%). The levels of these antibodies correlated with menstrual irregularities and a decrease in the antral follicle count. Thus, antibodies against CYP11A1, CYP19A1, and CYP21A2 have a high diagnostic value for POI. Three-antibody panel screening may improve the accuracy of POI diagnosis and be useful for identifying high-risk groups, early stages of the disease, and predicting POI progression.

Long-term exposure of metamifop affects sex differentiation and reproductive system of zebrafish (Danio rerio).

The extensive use of herbicide metamifop (MET) in rice fields for weeds control will inevitably lead to its entering into water environments and threaten the aquatic organisms. Previous researches have demonstrated that sublethal exposure of MET significantly affected zebrafish development. Yet the long-term toxicological impacts of MET on aquatic life remains unknown. Herein, we investigated the potential effects of MET (5 and 50 µg/L) on zebrafish during an entire life cycle. Since the expression level of male sex differentiation-related gene dmrt1 and sex hormone synthesis-related gene cyp19a1b were significantly changed after 50 µg/L MET exposure for only 7 days, indicators related to sex differentiation and reproductive system were further investigated. Results showed that the transcript of dmrt1 was inhibited, estradiol content increased and testosterone content decreased in zebrafish of both sexes after MET exposure at 45, 60 and 120 dpf. Histopathological sections showed that the proportions of mature germ cells in the gonads of male and female zebrafish (120 dpf) were significantly decreased. Moreover, males had elevated vitellogenin content while females did not after MET exposure; MET induced feminization in zebrafish, with the proportion of females significantly increased by 19.6% while that of males significantly decreased by 13.2% at 120 dpf. These results suggested that MET interfered with the expression levels of gonad development related-genes, disrupted sex hormone balance, and affected sex differentiation and reproductive system of female and male zebrafish, implying it might have potential endocrine disrupting effects after long-term exposure.

Embryonic exposure to water accommodated fraction of crude oil inhibits reproductive capability in adult female marine medaka (Oryzias melastigma).

The water accommodated fraction (WAF) of spilled crude oil is a severe threat to the health of marine fish. This study was conducted to investigate the effects of short-term embryonic exposure to the WAF on the ovarian development and reproductive capability of F0 adult female marine medaka (Oryzias melastigma). Following embryonic exposure to the WAF with nominal total petroleum hydrocarbon concentrations of 0.5, 5, 50, and 500 µg/L for 7 days, the number of spawned eggs and gonadosomatic indices of F0 adult females were significantly reduced at 130 days postfertilization. In these F0 adult females, the proportion of mature oocytes was significantly lower, the level of 17ß-estradiol was lower, and the level of testosterone was greater than those in control group. The mRNA levels of the follicle-stimulating hormone ß subunit, luteinizing hormone ß subunit, cytochrome P450 aromatase 19b, estrogen receptor α and ß, and androgen receptor α and ß genes were upregulated, while the mRNA level of the salmon-type gonadotropin-releasing hormone was downregulated in F0 adult females exposed to the WAF during the embryonic stage. Additionally, the methylation level of vitellogenin (vtg) in F0 adult females was significantly elevated, this might have, in turn, downregulated the mRNA level of vtg. The mortality rate of the unexposed F1 embryos was significantly increased and the hatching success was significantly reduced. These results collectively indicated the necessity of incorporating and evaluating the effects of short-term early-life exposure to crude oil in the assessment of risks to the reproductive health of marine fish.

Intragastric exposure of rats to silver nanoparticles modulates the redox balance and expression of steroid receptors in testes.

Nanosilver (AgNPs) is popular nanomaterials used in food industry that makes gastrointestinal tract an essential route of its uptake. The aim of the presented study was to assess the effects of intragastric exposure to AgNPs on redox balance and steroid receptors in the testes of adult Fisher 344 rats. The animals were exposed to 20 nm AgNPs (30 mg/kg bw/day, by gavage) for 7 and 28 days compared to saline (control groups). It was demonstrated that 7-day AgNPs administration resulted in increased level of total antioxidant status (TAS), glutathione reductase (GR) activity, lower superoxide dismutase activity (SOD), decreased glutathione (GSH) level and GSH/GSSG ratio, as well as higher estrogen receptor (ESR2) and aromatase (Aro) protein expression in Leydig cells compared to the 28-day AgNPs esposure. The longer-time effects of AgNPs exposition were associated with increased lipid hydroperoxidation (LOOHs) and decreased SOD activity and androgen receptor protein level. In conclusion, the present study demonstrated the adverse gastrointestinally-mediated AgNPs effects in male gonads. In particular, the short-term AgNPs exposure impaired antioxidant defence with concurrent effects on the stimulation of estrogen signaling, while the sub-chronic AgNPs exposition revealed the increased testicle oxidative stress that attenuated androgens signaling.

Synthesis, In vitro and In silico Studies of Novel Bis-triazolopyridopyrimidines from Curcumin Analogues as Potential Aromatase Agents.

Breast cancer remains a major global health issue, particularly affecting women and contributing significantly to mortality rates. Current treatments for estrogen receptor-positive breast cancers, such as aromatase inhibitors, are effective but often come with side effects and resistance issues. This study addresses these gaps by targeting aromatase, an enzyme crucial for estrogen synthesis, which plays a pivotal role in breast cancer progression. The innovative approach involves synthesizing novel bis-triazolopyridopyrimidines, designed to leverage the combined pharmacological benefits of pyridopyrimidine and 1,2,4-triazole structures, known for their potent aromatase inhibition and anti-cancer properties. These compounds were synthesized and characterized using 1H-NMR, 13C-NMR, and MS spectral analyses, and their anticancer efficacy was evaluated through MTT assays against MCF-7 breast cancer cell lines in vitro. Molecular docking analyses revealed strong binding energies with aromatase, particularly for compounds 5 b, 5 c, 10 a, and 10 b, indicating their potential as effective aromatase inhibitors. The study highlights these compounds as promising candidates for further development as therapeutic agents against breast cancer.

Developmental Delay and Male-Biased Sex Ratio in esr2b Knockout Zebrafish.

The estrogen receptor signaling pathway plays an important role in vertebrate embryonic development and sexual differentiation. There are four major estrogen receptors in zebrafish: esr1, esr2a, esr2b and gper. However, the specific role of different estrogen receptors in zebrafish is not clear. To investigate the role of esr2b in zebrafish development and reproduction, this study utilized TALENs technology to generate an esr2b knockout homozygous zebrafish line. The number of eggs laid by esr2b knockout female zebrafish did not differ significantly from that of wild zebrafish. The embryonic development process of wild-type and esr2b knockout zebrafish was observed, revealing a significant developmental delay in the esr2b knockout zebrafish. Additionally, mortality rates were significantly higher in esr2b knockout zebrafish than in their wild-type counterparts at 24 hpf. The reciprocal cross experiment between esr2b knockout zebrafish and wild-type zebrafish revealed that the absence of esr2b resulted in a decline in the quality of zebrafish oocytes, while having no impact on sperm cells. The knockout of esr2b also led to an abnormal sex ratio in the adult zebrafish population, with a female-to-male ratio of approximately 1:7. The quantitative PCR (qPCR) and in situ hybridization results demonstrated a significant downregulation of cyp19ab1b expression in esr2b knockout embryos compared to wild-type embryos throughout development (at 2 dpf, 3 dpf and 4 dpf). Additionally, the estrogen-mediated induction expression of cyp19ab1b was attenuated, while the estradiol-induced upregulated expression of vtg1 was disrupted. These results suggest that esr2b is involved in regulating zebrafish oocyte development and sex differentiation.

Small angle scattering reveals the orientation of cytochrome P450 19A1 in lipoprotein nanodiscs.

Human aromatase (CYP19A1), the cytochrome P450 enzyme responsible for conversion of androgens to estrogens, was incorporated into lipoprotein nanodiscs (NDs) and interrogated by small angle X-ray and neutron scattering (SAXS/SANS). CYP19A1 was associated with the surface and centered at the edge of the long axis of the ND membrane. In the absence of the N-terminal anchor, the amphipathic A'- and G'-helices were predominately buried in the lipid head groups, with the possibly that their hydrophobic side chains protrude into the hydrophobic, aliphatic tails. The prediction is like that for CYP3A4 based on SAXS employing a similar modeling approach. The orientation of CYP19A1 in a ND is consistent with our previous predictions based on molecular dynamics simulations and lends additional credibility to the notion that CYP19A1 captures substrates from the membrane.

Luteolin and its analog luteolin-7-methylether from Leonurus japonicus Houtt suppress aromatase-mediated estrogen biosynthesis to alleviate polycystic ovary syndrome by the inhibition of tumor progression locus 2.

ETHNOPHARMACOLOGICAL RELEVANCE: Leonurus japonicus Houtt (L. japonicus, Chinese motherwort), known as Yi Mu Cao which means "good for women", has long been widely used in China and other Asian countries to alleviate gynecological disorders, often characterized by estrogen dysregulation. It has been used for the treatment of polycystic ovary syndrome (PCOS), a common endocrine disorder in women but the underlying mechanism remains unknown. AIM OF THE STUDY: The present study was designed to investigate the effect and mechanism of flavonoid luteolin and its analog luteolin-7-methylether contained in L. japonicus on aromatase, a rate-limiting enzyme that catalyzes the conversion of androgens to estrogens and a drug target to induce ovulation in PCOS patients. MATERIALS AND METHODS: Estrogen biosynthesis in human ovarian granulosa cells was examined using ELISA. Western blots were used to explore the signaling pathways in the regulation of aromatase expression. Transcriptomic analysis was conducted to elucidate the potential mechanisms of action of compounds. Finally, animal models were used to assess the therapeutic potential of these compounds in PCOS. RESULTS: Luteolin potently inhibited estrogen biosynthesis in human ovarian granulosa cells stimulated by follicle-stimulating hormone. This effect was achieved by decreasing cAMP response element-binding protein (CREB)-mediated expression of aromatase. Mechanistically, luteolin and luteolin-7-methylether targeted tumor progression locus 2 (TPL2) to suppress mitogen-activated protein kinase 3/6 (MKK3/6)-p38 MAPK-CREB pathway signaling. Transcriptional analysis showed that these compounds regulated the expression of different genes, with the MAPK signaling pathway being the most significantly affected. Furthermore, luteolin and luteolin-7-methylether effectively alleviated the symptoms of PCOS in mice. CONCLUSIONS: This study demonstrates a previously unrecognized role of TPL2 in estrogen biosynthesis and suggests that luteolin and luteolin-7-methylether have potential as novel therapeutic agents for the treatment of PCOS. The results provide a foundation for further development of these compounds as effective and safe therapies for women with PCOS.

Discovery of Novel ERα and Aromatase Dual-Targeting PROTAC Degraders to Overcome Endocrine-Resistant Breast Cancer.

Estrogen receptor α (ERα) plays a pivotal role in the proliferation, differentiation, and migration of breast cancer (BC) cells, and aromatase (ARO) is a crucial enzyme in estrogen synthesis. Hence, it is necessary to inhibit estrogen production or the activity of ERα for the treatment of estrogen receptor-positive (ER+) BC. Herein, we present a new category of dual-targeting PROTAC degraders designed to specifically target ERα and ARO. Among them, compound 18c bifunctionally degrades and inhibits ERα/ARO, thus effectively suppressing the proliferation of MCF-7 cells while showing negligible cytotoxicity to normal cells. In vivo, 18c promotes the degradation of ERα and ARO and inhibits the growth of MCF-7 xenograft tumors. Finally, compound 18c demonstrates promising antiproliferative and ERα degradation activity against the ERαMUT cells. These findings suggest that 18c, being the inaugural dual-targeting degrader for ERα and ARO, warrants further advancement for the management of BC and the surmounting of endocrine resistance.

CYP19A1 Expression Is Controlled by mRNA Stability of the Upstream Transcription Factor AP-2γ in Placental JEG3 Cells.

CYP19A1 encodes aromatase, which converts testosterone to estrogen, and is induced during placental maturation. To elucidate the molecular mechanism underlying this function, histone methylation was analyzed using the placental cytotrophoblast cell line, JEG3. Treatment of JEG3 cells with 3-deazaneplanocin A, an inhibitor of several methyltransferases, resulted in increased CYP19A1 expression, accompanied by removal of the repressive mark H3K27me3 from the CYP19A1 promoter. However, this increase was not observed in cells treated with GSK126, another specific inhibitor for H3K27me3 methylation. Expression of TFAP2C, which encodes AP-2γ, a transcription factor that regulates CYP19A1, was also elevated on 3-deazaneplanocin A treatment. Interestingly, TFAP2C messenger RNA (mRNA) was readily degraded in JEG3 cells but protected from degradation in the presence of 3-deazaneplanocin A. TFAP2C mRNA contained N6-methyladenosines, which were reduced on drug treatment. These observations indicate that the TFAP2C mRNA undergoes adenosine methylation and rapid degradation, whereas 3-deazaneplanocin A suppresses methylation, resulting in an increase in AP-2γ levels. We conclude that the increase in AP-2γ expression via stabilization of the TFAP2C mRNA is likely to underlie the increased CYP19A1 expression.

Roles of Ferric Peroxide Anion Intermediates (Fe3+O2 -, Compound 0) in Cytochrome P450 19A1 Steroid Aromatization and a Cytochrome P450 2B4 Secosteroid Oxidation Model.

Cytochrome P450 (P450, CYP) 19A1 is the steroid aromatase, the enzyme responsible for the 3-step conversion of androgens (androstenedione or testosterone) to estrogens. The final step is C-C bond scission (removing the 19-oxo group as formic acid) that proceeds via a historically controversial reaction mechanism. The two competing mechanistic possibilities involve a ferric peroxide anion (Fe3+O2 -, Compound 0) and a perferryl oxy species (FeO3+, Compound I). One approach to discern the role of each species in the reaction is with the use of oxygen-18 labeling, i.e., from 18O2 and H2 18O of the reaction product formic acid. We applied this approach, using several technical improvements, to study the deformylation of 19-oxo-androstenedione by human P450 19A1 and of a model secosteroid, 3-oxodecaline-4-ene-10-carboxaldehyde (ODEC), by rabbit P450 2B4. Both aldehyde substrates were sensitive to non-enzymatic acid-catalyzed deformylation, yielding 19-norsteroids, and conditions were established to avoid issues with artifactual generation of formic acid. The Compound 0 reaction pathway predominated (i.e., Fe3+O2 -) in both P450 19A1 oxidation of 19-oxo-androstenedione and P450 2B4 oxidation of ODEC. The P450 19A1 results contrast with our prior conclusions (J. Am. Chem. Soc. 2014, 136, 15016-16025), attributed to several technical modifications.