Conversion Of Androgens Research Articles

Utilisation of the Innovative [18F]-Labelled Radiotracer [18F]-BIBD-071 Within HR+ Breast Cancer Xenograft Mouse Models.

Background/Objectives: Aromatase plays a crucial role in the conversion of androgens to oestrogens and is often overexpressed in hormone-dependent tumours, particularly breast cancer. [18F]BIBD-071, which has excellent binding affinity for aromatase and good pharmacokinetics, has potential for the diagnosis and treatment of aromatase-related diseases. The MCF-7 cell line, which is hormone receptor-positive (HR+), was used in the assessment of the novel [18F]-labelled radiotracer [18F]BIBD-071 via positron emission tomography (PET) imaging of an HR+ breast cancer xenograft model. Methods: [18F]BIBD-071 was synthesised, radiolabelled, and then subjected to in vitro stability testing. MCF-7 cells were cultured and implanted into BALB/c nude mice to establish subcutaneous tumour models. MicroPET/CT imaging was conducted after injection of the tracer at 1 and 2 h, and a blocking study was also conducted using the aromatase inhibitor letrozole. A block experiment was used to prove the specificity of the probe. Biodistribution studies were performed at 0.5, 1, and 2 h post injection (p.i.). Immunofluorescence was used to assess aromatase expression in MCF-7 cells. Results: [18F]BIBD-071 showed excellent in vitro stability and specific uptake in an MCF-7 xenograft tumour model. MicroPET/CT imaging at 1 and 2 h p.i. revealed excellent tumour visualisation with a favourable tumour-to-background ratio. Biodistribution data revealed high tracer uptake in the liver, small intestine, and stomach, with significant washout from the bloodstream and tumour over time. The tumour uptakes at 0.5 h, 1 h, and 2 h were 3.84 ± 0.13, 2.5 ± 0.17, and 2.54 ± 0.32, respectively. The tumour uptake significantly decreased between 0.5 h and 1 h (p < 0.0001), whereas there was no significant difference between 1 and 2 h. The tumour/background ratios at 0.5 h, 1 h, and 2 h were 1.19 ± 0.03, 1.12 ± 0.17, and 1.42 ± 0.11, respectively. Immunofluorescence confirmed robust aromatase expression in MCF-7 cells, which was correlated with [18F]BIBD-071 tumour uptake. Conclusions: [18F]BIBD-071 is a promising PET tracer for diagnosing and monitoring HR+ breast cancer, warranting further research into hormone-dependent cancers.

Machine Learning-Based Drug Repositioning of Novel Human Aromatase Inhibitors Utilizing Molecular Docking and Molecular Dynamic Simulation

In the continuous search for potential drug-like molecules for diseases, drug repurposing offers a solution by identifying new roles for the existing drugs. For breast cancer, which is the leading cause of death among women, discovering a new drug with fewer side effects can take more than a year, and drug repurposing provides a faster alternative. In this study, we used machine learning (ML) and structure-based screening to evaluate molecules from the ChEMBL library against Human Aromatase, an enzyme that is involved in the conversion of androgens to estrogen. The virtual screening output identified 148 potential compounds. These compounds were further subjected to detailed structure-based virtual screening, followed by assessment of induced fit docking, quantum-based docking and ADMET properties. The top compound, CHEMBL502014 and the co-crystallized ligand (reference) were evaluated through MD simulations for 100 ns. The results indicated that the CHEMBL502014-Aromatase complex demonstrated better conformational stability throughout the simulation compared to the reference ligand. Based on these analyses, we propose CHEMBL502014 and other top compounds with known activities against various proteins as potential candidates for anti-cancer activity against breast cancer. These compounds should be further evaluated using experimental assays to confirm their effectiveness against breast cancer.

Anastrozole improves height outcomes in growing children with congenital adrenal hyperplasia due to 21-OHD.

Hyperandrogenemia resulting in estrogen-mediated accelerated bone maturation and early growth plate fusion contributes to short stature in children with congenital adrenal hyperplasia (CAH) due to 21OHD. Aromatase inhibitors block androgen conversion to estrogen and have been used off-label in children with short stature to improve adult height. There are no adequately powered studies examining the use of aromatase inhibitors in children with CAH with advanced bone age and reduced predicted adult height. Records of CAH patients treated with anastrozole were reviewed. Z-scores of bone age, predicted adult height and height corrected for bone age were examined over an 8-year period. Outcome changes were analyzed using weighted mixed-effects models, adjusting for sex, diagnosis, age at diagnosis, and average hydrocortisone dose before and during treatment with anastrozole. In 60 patients (26 females, 52 classic, 8 non-classic) started on anastrozole therapy, the mean bone age Z-score decreased from 4.2 to 2.0 at 4 years and 1.3 at 6 years (both p <0.001); predicted adult height Z-score improved from -2.1 to -0.45 at 4 years and 0.18 at 6 years (both p <0.001); corrected height Z-scores improved from -1.7 to -0.33 at 4 years and 0.18 at 6 years (p <0.001). There was no significant difference in the average total daily hydrocortisone dose used before or during treatment. Anastrozole decreased the rate of bone maturation and led to improved height outcomes, indicating that anastrozole could have a role as an adjunct therapy in children with CAH and advanced bone age.

Sexual Dimorphism in Sex Hormone Metabolism in Human Skeletal Muscle Cells in Response to Different Testosterone Exposure.

Muscle tissue is an important target of sex steroids, and particularly, testosterone plays essential roles in muscle cell metabolism. Wide ranges of studies have reported sex differences in basal muscle steroidogenesis, and recently several genes have been identified to be regulated by androgen response elements that show innate sex differences in muscle. However, studies accounting for and demonstrating cell sexual dimorphism in vitro are still scarce and not well characterized. Here, we demonstrated the ability of 46XX and 46XY human primary skeletal muscle cells to differently activate steroidogenesis in vitro, likely related to sex-chromosome onset, and to differently induce hormone release after increasing doses of testosterone exposure. Cells were treated with testosterone at concentrations of 0.5, 2, 5, 10, 32, and 100 nmol/L for 24 h. Variations in 17β-HSD, 5α-R2, CYP-19 expression, DHT, estradiol, and androstenedione release, as well as IL6 and IL8 release, were analyzed, respectively, by RT-PCR, ELISA, and luminex-assay. Following testosterone treatments, and potentially at any concentration level, an increase in the expression of 17β-HSD, 5α-R2, and CYP-19 was observed in 46XY cells, accompanied by elevated levels of DHT, androstenedione, and IL6/IL8 release. Following the same treatment, 46XX cells exhibited an increase in 5α-R2 and CYP-19 expression, a conversion of androgens to estrogens, and a reduction in IL6 and IL8 release. In conclusion, this study demonstrated that sex-chromosome differences may influence in vitro muscle cell steroidogenesis and hormone homeostasis, which are pivotal for skeletal muscle metabolism.

Impact of Letrozole on Prevention of Early Onset Ovarian Hyperstimulation Syndrome in GnRH Antagonist Protocol: A Randomized Controlled Trial

Abstract Background Ovarian hyperstimulation syndrome (OHSS) is a risk associated with assisted reproductive technology. There is a link between higher incidences of OHSS and higher blood estrogen levels. With its strong, targeted, and reversible inhibition of aromatase and E synthetase, the nonsteroidal aromatase inhibitor letrozole can prevent the conversion of androgens into estrogens. Methods Study populations were divided into two equal groups: Group I: Consisted of 85 women who received controlled ovarian stimulation with a conventional antagonist protocol and letrozole. Group II: Consisted of 85 women who received controlled ovarian stimulation with a conventional GnRH antagonist protocol and a placebo. Results There were statistically significant differences among the groups in terms of Estradiol level on Trigger Day (p = 0.037), Number of oocytes retrieved (p = 0.018). The total days of stimulation and cumulative Gonadotropin dose were significantly lower in the Letrozole group (p = 0.045). There were no significant differences between the groups as regard endometrial thickness at trigger day, number of fertilized oocytes, fertilization rate, embryos transferred per cycle, and fresh embryos transferred, mild and critical early onset OHSS, Cycle cancels, Biochemical pregnancy, and Clinical pregnancy between the two groups (P &amp;gt; 0.05). There was a significant difference as regard moderate and severe early onset OHSS between the two groups (P &amp;lt; 0.05). Conclusion We've concluded that for PCOS patients facing a high risk of OHSS, supplementing the GnRH-ant protocol with LE offers a safer, more effective, cost-efficient, and patient-friendly approach compared to the traditional GnRH-ant protocol. The use of LE alongside conventional protocols might alleviate severe forms of OHSS, even among those at extreme risk, without compromising the potential for implantation, pregnancy, and delivery

Letrozole-induced reversible acute heart failure.

Letrozole is an aromatase inhibitor (AI), which suppresses plasma estrogen levels by inhibiting the aromatase enzyme, that causes the conversion of androgens to estrogen in peripheral tissues. There is very few information in the literature regarding the development of acute heart failure after AI use. We would like to report a case of a patient who was started letrozole for hormonal treatment and developed acute heart failure due to this. Fifty-seven-year-old woman with hormone positive breast cancer was operated after neoadjuvant chemotherapy and received radiotherapy. Letrozole treatment was initiated after radiotherapy and the patient presented to the emergency department after two weeks with cough and dyspnea. Ejection fraction decreased to 20% and acute heart failure developed. Letrozole treatment was stopped. Afterwards, improvement in the patient's cardiac functions was observed. Letrozole-induced heart failure was thought to be reversible. Letrozole is one of the most commonly used HT in the treatment of hormone positive breast cancer. It may rarely cause cardiac side effects. It is very important to make patients aware of these issues and to be consulted by cardiology in case of possible cardiac symptoms.

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

AbstractCytochrome 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 H218O 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.

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.

Safety of Antiandrogens for the Treatment of Female Androgenetic Alopecia with Respect to Gynecologic Malignancies.

The most common type of alopecia in women is female androgenetic alopecia (FAGA), characterized by progressive hair loss in a patterned distribution. Many oral therapies, including spironolactone (an aldosterone antagonist), androgen receptor blockers (e.g., flutamide/bicalutamide), 5-alpha-reductase inhibitors (e.g., finasteride/dutasteride), and oral contraceptives, target the mechanism of androgen conversion and binding to its respective receptor and therefore could be administered for the treatment of FAGA. Despite significant advances in the oral treatment of FAGA, its management in patients with a history of gynecological malignancies, the most common cancers in women worldwide, may still be a concern. In this review, we focus on the safety of antiandrogens for the treatment of FAGA patients. For this purpose, a targeted literature review was conducted on PubMed, utilizing the relevant search terms. To sum up, spironolactone seems to be safe for the systemic treatment of FAGA, even in high-risk populations. However, a general uncertainty remains regarding the safety of other medications in patients with a history of gynecologic malignancies, and further studies are needed to evaluate their long-term safety in patients with FAGA and risk factors to establish an optimal risk assessment and treatment selection protocol.

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 relevanceLeonurus 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 studyThe 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 methodsEstrogen 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. ResultsLuteolin 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. ConclusionsThis 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.

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.

Endothelial dysfunction in breast cancer survivors on aromatase inhibitors: changes over time

BackgroundBreast cancer is estimated to comprise about 290,560 new cases in 2022. Aromatase inhibitors (AIs) are recommended as adjuvant treatment for estrogen-receptor positive (ER+) breast carcinoma in postmenopausal women, which includes approximately two-thirds of all women with breast cancer. AIs inhibit the peripheral conversion of androgens to estrogen by deactivation of the aromatase enzyme, leading to a reduction in serum estrogen level in postmenopausal women with ER+ breast carcinoma. Estrogen is known for its cardiovascular (CV) protective properties through a variety of mechanisms including vasodilation of blood vessels and inhibition of vascular injury resulting in the prevention of atherosclerosis. In clinical trials and prospective cohorts, the long-term use of AIs can increase the risk for hypertension and hyperlipidemia. Studies demonstrate mixed results as to the impact of AIs on actual CV events and overall survival.MethodsA single arm longitudinal study of 14 postmenopausal women with ER+ breast cancer prescribed adjuvant AIs at the University of Minnesota (UMN). Subjects with a history of known tobacco use, hypertension, hyperlipidemia, and diabetes were excluded to eliminate potential confounding factors. Participants underwent routine labs, blood pressure assessments, and vascular testing at baseline (prior to starting AIs) and at six months. Vascular assessment was performed using the EndoPAT 2000 and HDI/PulseWave CR-2000 Cardiovascular Profiling System and pulse contour analysis on two occasions as previously described. Vascular measurements were conducted by one trained vascular technician. Assessments were performed in triplicate, and the mean indices were used for analyses. All subjects were on an AI at the follow-up visit. The protocol was approved by the UMN Institutional Review Board and all participants were provided written informed consent. Baseline and follow-up characteristics were compared using Wilcoxon signed-rank tests. Analyses were performed using R version 3.6.1 (R Foundation for Statistical Computing, Vienna, Austria).ResultsAfter six months of AI treatment, EndoPAT® ratio declined to a median 1.12 (Q1: 0.85, Q3: 1.86; p = 0.045; Figure 1) and median estradiol levels decreased to 2 pg/mL (Q1: 2, Q3: 3; p=0.052). There was no evidence of association between change in EndoPAT® and change in estradiol level (p = 0.91). There were no statistically significant changes in small or large arterial elasticity.ConclusionsWe hypothesize that long-term use of AI can lead to persistent endothelial dysfunction, and further investigation is necessary. In our study, patients were on AI for approximately 5-10 years. As a result, we do not have data on whether these changes, such as EndoPAT® ratio and the elasticity of small and large arterial, are reversible with discontinuation of AI. These findings set the stage for a larger study to more conclusively determine the association between AI exposure and cardiovascular outcomes. Further studies should evaluate for multivariate associations withmodifiable risk factors for CV disease.

Identification, Expression and Evolutional Analysis of Two cyp19-like Genes in Amphioxus.

The mechanism of sex determination and differentiation in animals remains a central focus of reproductive and developmental biology research, and the regulation of sex differentiation in amphioxus remains poorly understood. Cytochrome P450 Family 19 Subfamily A member 1 (CYP19A1) is a crucial sex differentiation gene that catalyzes the conversion of androgens into estrogens. In this study, we identified two aromatase-like genes in amphioxus: cyp19-like1 and cyp19-like2. The cyp19-like1 is more primitive and may represent the ancestral form of cyp19 in zebrafish and other vertebrates, while the cyp19-like2 is likely the result of gene duplication within amphioxus. To gain further insights into the expression level of these two aromatase-like, we examined their expression in different tissues and during different stages of gonad development. While the expression level of the two genes differs in tissues, both are highly expressed in the gonad primordium and are primarily localized to microsomal membrane systems. However, as development proceeds, their expression level decreases significantly. This study enhances our understanding of sex differentiation mechanisms in amphioxus and provides valuable insights into the formation and evolution of sex determination mechanisms in vertebrates.

The spatio-temporal distribution of aromatase cytochrome in ovary throughout the canine oestrous cycle.

New animal welfare legislation and ethical guidelines encourage alternative approaches for canine contraception, instead of surgical gonadectomy which is considered invasive and unjustified in healthy dogs. Reversible contraception might be achieved by inhibition of aromatase (CYP19), an enzyme catalysing the conversion of androgens to oestrogens. This study provides insights into the spatio-temporal expression and distribution of aromatase in canine ovarian tissue. Ovarian tissue was collected from 39 healthy and sexually mature bitches during different stages of the oestrous cycle: pro-oestrus (n =8), oestrus (n =12), dioestrus (n =9) (luteal phase) and anoestrus (n =10). Localisation of cytochrome P450 aromatase was determined by immunohistochemistry. Aromatase activity in the dog is high during pro-oestrus, ovulation and early dioestrus. Comparing types of follicles and corpora lutea, the highest aromatase abundance was found in antral follicles and luteinising follicles, whereas corpora lutea and early antral follicles showed an intermediate presence of the enzyme. Interesting was the high abundance of aromatase in luteinising theca interna cells, prevailing over granulosa cells. Understanding of cells involved in oestradiol production is important for targeted inhibition of oestradiol synthesis, possibly offering an approach for contraception and suppression of oestrus.

AKR1C3 in carcinomas: from multifaceted roles to therapeutic strategies.

Aldo-Keto Reductase Family 1 Member C3 (AKR1C3), also known as type 5 17β-hydroxysteroid dehydrogenase (17β-HSD5) or prostaglandin F (PGF) synthase, functions as a pivotal enzyme in androgen biosynthesis. It catalyzes the conversion of weak androgens, estrone (a weak estrogen), and PGD2 into potent androgens (testosterone and 5α-dihydrotestosterone), 17β-estradiol (a potent estrogen), and 11β-PGF2α, respectively. Elevated levels of AKR1C3 activate androgen receptor (AR) signaling pathway, contributing to tumor recurrence and imparting resistance to cancer therapies. The overexpression of AKR1C3 serves as an oncogenic factor, promoting carcinoma cell proliferation, invasion, and metastasis, and is correlated with unfavorable prognosis and overall survival in carcinoma patients. Inhibiting AKR1C3 has demonstrated potent efficacy in suppressing tumor progression and overcoming treatment resistance. As a result, the development and design of AKR1C3 inhibitors have garnered increasing interest among researchers, with significant progress witnessed in recent years. Novel AKR1C3 inhibitors, including natural products and analogues of existing drugs designed based on their structures and frameworks, continue to be discovered and developed in laboratories worldwide. The AKR1C3 enzyme has emerged as a key player in carcinoma progression and therapeutic resistance, posing challenges in cancer treatment. This review aims to provide a comprehensive analysis of AKR1C3's role in carcinoma development, its implications in therapeutic resistance, and recent advancements in the development of AKR1C3 inhibitors for tumor therapies.

Effects of Letrozole Treatment and Vitamin C Supplementation on Morphology, Endoplasmic Reticulum Stress, Programmed Cell Death, and Oxidative Stress in the Small Intestine of Adult Male Rats.

Estrogens are hormones that play an important role in the digestive tract, including in men. Letrozole is an inhibitor of cytochrome P450 aromatase, an enzyme converting androgens to estrogens. The use of letrozole may cause oxidative stress and endoplasmic reticulum stress in the cells. Factors modulating cellular stress may include vitamin C. The purpose of this study was to examine whether letrozole and/or vitamin C supplementation can affect the morphology of the small intestine, the parameters of endoplasmic reticulum stress, programmed cell death markers, and oxidative damage. Three-month-old male rats were divided into four groups and treated with the following: (I) CTRL-water; (II) CTRL+C-L-ascorbic acid; (III) LET-letrozole; and (IV) LET+C-letrozole + L-ascorbic acid. The morphometrical measurements included epithelial thickness, crypt and lumen area, crypt perimeter, nuclei number in the crypt, and the cell size of crypts. The expression levels of PERK, caspase-3, and catalase were determined. Significant differences in the morphometrical measurements and immunoexpression were observed. This may indicate that chronic treatment with letrozole can affect morphology and induce ER stress, oxidative stress, and programmed cell death in the epithelial cells of the small intestine of adult male rats. Vitamin C supplementation exerts an effect on some parameters of the molecular processes.

PHARMACOINFORMATICS ANALYSIS OF MORUS MACROURA FOR DRUG DISCOVERY AND DEVELOPMENT

Objective: Pharmacoinformatics is an innovative approach rapidly evolving in pharmaceutical research and drug development. This study focuses on analysing Morus macroura, a plant species with untapped pharmacological potential. This investigation aims to leverage pharmacoinformatics techniques to unveil the hidden potential of Morus macroura in drug discovery and development.&#x0D; Methods: The study includes analyses of protein-protein interactions, deep learning docking, adsorption tests, distribution, metabolism, excretion, molecular dynamics simulations and free energy calculation using Molecular Mechanics Generalized Born Surface Area (MMGBSA).&#x0D; Results: Nine active compounds were identified in Morus macroura, namely Andalasin A, Guangsangon K, Guangsangon L, Guangsangon M, Guangsangon N, Macrourone C, Mulberrofuran G, Mulberrofuran K, and Mulberroside C. These compounds exhibit protein-protein interaction activities against a cytochrome P450 monooxygenase that catalyses the conversion of C19 androgens. These plant compounds influence aromatase excess syndrome, deficiency, and ovarian dysgenesis. Regarding drug-likeness, Mulberroside C and Macrourone C demonstrated good absorption potential by adhering to Lipinski's rule of five. Deep learning docking simulations yielded affinity results of-9.62 kcal/mol for Guangsangon M,-10.44 kcal/mol for Macrourone C, and-10.99 kcal/mol for Guangsangon L. Subsequent molecular dynamics simulations indicated that Guangsangon L and Macrourone C remained stable during a 100 ns simulation.&#x0D; Conclusion: Morus macroura interacts with important proteins, particularly CYP19A1, which might influence health conditions like aromatase excess syndrome and ovarian dysgenesis. These findings provide potential paths for addressing specific health issues and advancing drug development. Molecular dynamics simulations indicated that Guangsangon L and Macrourone C remained stable during simulation.

Aromatase deficiency in transplanted bone marrow cells improves vertebral trabecular bone quantity, connectivity, and mineralization and decreases cortical porosity in murine bone marrow transplant recipients.

Estradiol is an important regulator of bone accumulation and maintenance. Circulating estrogens are primarily produced by the gonads. Aromatase, the enzyme responsible for the conversion of androgens to estrogen, is expressed by bone marrow cells (BMCs) of both hematopoietic and nonhematopoietic origin. While the significance of gonad-derived estradiol to bone health has been investigated, there is limited understanding regarding the relative contribution of BMC derived estrogens to bone metabolism. To elucidate the role of BMC derived estrogens in male bone, irradiated wild-type C57BL/6J mice received bone marrow cells transplanted from either WT (WT(WT)) or aromatase-deficient (WT(ArKO)) mice. MicroCT was acquired on lumbar vertebra to assess bone quantity and quality. WT(ArKO) animals had greater trabecular bone volume (BV/TV p = 0.002), with a higher trabecular number (p = 0.008), connectivity density (p = 0.017), and bone mineral content (p = 0.004). In cortical bone, WT(ArKO) animals exhibited smaller cortical pores and lower cortical porosity (p = 0.02). Static histomorphometry revealed fewer osteoclasts per bone surface (Oc.S/BS%), osteoclasts on the erosion surface (ES(Oc+)/BS, p = 0.04) and low number of osteoclasts per bone perimeter (N.Oc/B.Pm, p = 0.01) in WT(ArKO). Osteoblast-associated parameters in WT(ArKO) were lower but not statistically different from WT(WT). Dynamic histomorphometry suggested similar bone formation indices' patterns with lower mean values in mineral apposition rate, label separation, and BFR/BS in WT(ArKO) animals. Ex vivo bone cell differentiation assays demonstrated relative decreased osteoblast differentiation and ability to form mineralized nodules. This study demonstrates a role of local 17β-estradiol production by BMCs for regulating the quantity and quality of bone in male mice. Underlying in vivo cellular and molecular mechanisms require further study.

Charged Amino Acids in the Transmembrane Helix Strongly Affect the Enzyme Activity of Aromatase.

Estrogens play critical roles in embryonic development, gonadal sex differentiation, behavior, and reproduction in vertebrates and in several human cancers. Estrogens are synthesized from testosterone and androstenedione by the endoplasmic reticulum membrane-bound P450 aromatase/cytochrome P450 oxidoreductase complex (CYP19/CPR). Here, we report the characterization of novel mammalian CYP19 isoforms encoded by CYP19 gene copies. These CYP19 isoforms are all defined by a combination of mutations in the N-terminal transmembrane helix (E42K, D43N) and in helix C of the catalytic domain (P146T, F147Y). The mutant CYP19 isoforms show increased androgen conversion due to the KN transmembrane helix. In addition, the TY substitutions in helix C result in a substrate preference for androstenedione. Our structural models suggest that CYP19 mutants may interact differently with the membrane (affecting substrate uptake) and with CPR (affecting electron transfer), providing structural clues for the catalytic differences.

Aromatase Inhibitors as a Promising Direction for the Search for New Anticancer Drugs.

Aromatase is an enzyme that plays a crucial role in the biosynthesis of estrogens, which are hormones that contribute to the growth of certain types of breast cancer. In particular, aromatase catalyzes the conversion of androgens (male hormones) into estrogens (female hormones) in various tissues, including the adrenal glands, ovaries, and adipose tissue. Given the role of estrogen in promoting the growth of hormone-receptor-positive breast cancers, aromatase has become an important molecular target for the development of anticancer agents. Aromatase inhibitors can be classified into two main groups based on their chemical structure: steroidal and non-steroidal inhibitors. This work presents a review of the literature from the last ten years regarding the search for new aromatase inhibitors. We present the directions of search, taking into account the impact of structure modifications on anticancer activity.