DHT Treatment Research Articles

Dihydrotanshinone I induces necroptosis and cell cycle arrest in gastric cancer through the PTPN11/p38 pathway

In this study, MTT assays, apoptosis detection, immunofluorescence, and functional studies were used to elucidate the mechanisms underlying the effects of dihydrotanshinone I (DHT) on gastric cancer cells. Drug target prediction and analysis were conducted to identify potential targets of DHT. MTT assay revealed significant inhibition of AGS and HGC27 cells by DHT. Morphological changes, including nuclear shrinkage and the induction of necrotic cell death, were observed in DHT-treated gastric cancer cells, along with cell cycle arrest at the G2/M phase. Further analysis revealed potential targets of DHT, including PTPN11, which is highly expressed in gastric cancer cells. DHT treatment increased necrosis-related proteins (RIPK1/RIPK3/MLKL) and downregulated cell cycle-related proteins (CDC25C and CDK1) levels in gastric cancer cells. After DHT treatment, PTPN11 protein expression decreased. Furthermore, DHT significantly increased the phosphorylated p38/JNK protein level, with the phosphorylated p38 protein notably enriched in the nucleus. These functional studies indicate that PTPN11 plays a key role in mediating the effects of DHT, including cell cycle regulation and necrosis induction. In conclusion, PTPN11 is a central target through which DHT affects gastric cancer cells, regulating downstream pathways involved in necroptosis (p38/RIPK1/RIPK3/MLKL/JNK) and cell cycle arrest (p38/CDC25C/CDK1).

Dihydrotanshinone I targets ESR1 to induce DNA double-strand breaks and proliferation inhibition in hepatocellular carcinoma

BackgroundDue to its high incidence and elevated mortality, hepatocellular carcinoma (HCC) has emerged as a formidable global healthcare challenge. The intricate interplay between gender-specific disparities in both incidence and clinical outcomes has prompted a progressive recognition of the substantial influence exerted by estrogen and its corresponding receptors (ERs) upon HCC pathogenesis. Estrogen replacement therapy (ERT) emerged for the treatment of HCC by administering exogenous estrogen. However, the powerful side effects of estrogen, including the promotion of breast cancer and infertility, hinder the further application of ERT. Identifying effective therapeutic targets for estrogen and screening bioactive ingredients without E2-like side effects is of great significance for optimizing HCC ERT. MethodsIn this study, we employed an integrative approach, harnessing data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, clinical paraffin sections, adenoviral constructs as well as in vivo studies, to unveil the association between estrogen, estrogen receptor α (ESR1) and HCC. Leveraging methodologies encompassing molecular dynamics simulation and cellular thermal shift assay (CETSA) were used to confirm whether ESR1 is a molecular target of DHT. Multiple in vitro and in vivo experiments were used to identify whether i) ESR1 is a crucial gene that promotes DNA double-strand breaks (DSBs) and proliferation inhibition in HCC, ii) Dihydrotanshinone I (DHT), a quinonoid monomeric constituent derived from Salvia miltiorrhiza (Dan shen) exerts anti-HCC effects by regulating ESR1 and subsequent DSBs, iii) DHT has the potential to replace E2. ResultsDHT could target ESR1 and upregulate its expression in a concentration-dependent manner. This, in turn, leads to the downregulation of breast cancer type 1 susceptibility protein (BRCA1), a pivotal protein involved in the homologous recombination repair (HRR) process. The consequence of this downregulation is manifested through the induction of DSBs in HCC, subsequently precipitating a cascade of downstream events, including apoptosis and cell cycle arrest. Of particular significance is the comparative assessment of DHT and isodose estradiol treatments, which underscores DHT's excellent HCC-suppressive efficacy without concomitant perturbation of endogenous sex hormone homeostasis. ConclusionOur findings not only confirm ESR1 as a therapeutic target in HCC management but also underscores DHT's role in upregulating ESR1 expression, thereby impeding the proliferation and invasive tendencies of HCC. In addition, we preliminarily identified DHT has the potential to emerge as an agent in optimizing HCC ERT through the substitution of E2.

Dihydrotanshinone I exhibits antitumor effects via β-catenin downregulation in papillary thyroid cancer cell lines

Thyroid cancer is the most common endocrine carcinoma and, among its different subtypes, the papillary subtype (PTC) is the most frequent. Generally, PTCs are well differentiated, but a minor percentage of PTCs are characterized by a worse prognosis and more aggressive behavior. Phytochemicals, naturally found in plant products, represent a heterogeneous group of bioactive compounds that can interfere with cell proliferation and the regulation of the cell cycle, taking part in multiple signaling pathways that are often disrupted in tumor initiation, proliferation, and progression. In this work, we focused on 15,16-dihydrotanshinone I (DHT), a tanshinone isolated from Salvia miltiorrhiza Bunge (Danshen). We first evaluated DHT biological effect on PTC cells regarding cell viability, colony formation ability, and migration capacity. All of these parameters were downregulated by DHT treatment. We then investigated gene expression changes after DHT treatment by performing RNA-seq. The analysis revealed that DHT significantly reduced the Wnt signaling pathway, which plays a role in various diseases, including cancer. Finally, we demonstrate that DHT treatment decreases protein levels of β-catenin, a final effector of canonical Wnt signaling pathway. Overall, our data suggest a possible use of this nutraceutical as an adjuvant in the treatment of aggressive papillary thyroid carcinoma.

IGFBP-rP1 is a potential therapeutic target in androgenic alopecia.

The available interventions for androgenic alopecia (AGA), the most common type of hair loss worldwide, remain limited. The insulin growth factor (IGF) system may play an important role in the pathogenesis of AGA. However, the exact role of IGF binding protein-related protein 1 (IGFBP-rP1) in hair growth and AGA has not been reported. In this study, we first found periodic variation in IGFBP-rP1 during the hair cycle transition in murine hair follicles (HFs). We further demonstrated that IGFBP-rP1 levels were lower in the serum and scalp HFs of individuals with AGA than in those of healthy controls. Subsequently, we verified that IGFBP-rP1 had no cytotoxicity to human outer root sheath cells (HORSCs) and that IGFBP-rP1 reversed the inhibitory effects of DHT on the migration of HORSCs invitro. Finally, a DHT-induced AGA mouse model was created. The results revealed that the expression of IGFBP-rP1 in murine HFs was downregulated after DHT treatment and that subcutaneous injection of IGFBP-rP1 delayed catagen occurrence and prolonged the anagen phase of HFs in mice with DHT-induced AGA. The present work shows that IGFBP-rP1 is involved in hair cycle transition and exhibits great therapeutic potential for AGA.

Dihydrotanshinone I reduces H9c2 cell damage by regulating AKT and MAPK signaling pathways.

Cardiovascular disease is the deadliest disease in the world. Previous studies have shown that Dihydrotanshinone I (DHT) can improve cardiac function after myocardial injury. This study aimed to observe the protective effect and mechanism of DHT on H9c2 cells by establishing an oxygen-glucose deprivation/reoxygenation (OGD/R) injury model. By constructing OGD/R injury simulation of H9c2 cells in a myocardial injury model, the proliferation of H9c2 cells treated with DHT concentrations of 0.1μmol/L were not affected at 24, 48, and 72h. DHT can significantly reduce the apoptosis of H9c2 cells caused by OGD/R. Compared with the OGD/R group, DHT treatment significantly reduced the level of MDA and increased the level of SOD in cells. DHT treatment of cells can significantly reduce the levels of ROS and Superoxide in mitochondria in H9c2 cells caused by OGD/R and H2O2. DHT significantly reduced the phosphorylation levels of P38MAPK and ERK in H9c2 cells induced by OGD/R, and significantly increased the phosphorylation levels of AKT in H9c2 cells. DHT can significantly reduce the oxidative stress damage of H9c2 cells caused by H2O2 and OGD/R, thereby reducing the apoptosis of H9c2 cells. And this may be related to regulating the phosphorylation levels of AKT, ERK, and P38MAPK.

Reproductive Profile of Neuronal Androgen Receptor Knockout Female Mice With a Low Dose of DHT.

Hyperandrogenism and polycystic ovarian syndrome result from the imbalance or increase of androgen levels in females. Androgen receptor (AR) mediates the effects of androgens, and this study examines whether neuronal AR plays a role in reproduction under normal and increased androgen conditions in female mice. The neuron-specific AR knockout (KO) mouse (SynARKO) was generated from a female mouse (synapsin promoter driven Cre) and a male mouse (Ar fl/y). Puberty onset and the levels of reproductive hormones such as LH, FSH, testosterone, and estradiol were comparable between the control and the SynARKO mice. There were no differences in cyclicity and fertility between the control and SynARKO mice, with similar impairment in both groups on DHT treatment. Neuronal AR KO, as in this SynARKO mouse model, did not alleviate the infertility associated with DHT treatment. These studies suggest that neuronal AR KO neither altered reproductive function under physiological androgen levels, nor restored fertility under hyperandrogenic conditions.

SAT362 Low-dose DHT’s Effects On Gluconeogenesis And Energy Metabolism Are Ameliorated By Central Nervous System Knockout Of The Androgen Receptor

Abstract Disclosure: V. Ubba: None. S. joseph: None. R. Akbar: None. M. Dsilva: None. S. Wu: None. Polycystic ovarian syndrome (PCOS) is a leading cause of infertility in women of reproductive age. Mostly, the level of androgens are deviated from their physiological values in females, resulting in hyperandrogenemia. Androgen manifests its function in the cells via the Androgen Receptor (AR), making it a prime factor for studying PCOS pathophysiology. We generated central nervous system (CNS) specific AR knockout mouse (SynARKO), using synapsin promoter driven cre, to examine its role under normal and hyperandrogenemic conditions in female mice. Assessment of reproductive parameters under physiological levels of androgens, revealed no differences in the cyclicity and fertility of SynARKO mice when compared to Control (Con-veh) mice. These parameters were altered under hyperandrogenemia (induced using DHT) in Control mice (Con-DHT) mice and were not rescued in the SynARKO- DHT mice, suggesting CNS AR is dispensable to reproductive features in females. Evaluation of metabolic functions by Glucose tolerance test, we observed alleviated glucose intolerance in SynARKO-DHT (4 months). Energy expenditure and food intake were increased in Con-DHT mice compared to Con-veh, while showing no further differences in SynARKO-DHT mice compared to SynARKO-veh. At the molecular level, DHT treatment showed increased phosphorylated Akt in hypothalamus of control mice. Interestingly, it was restored in synARKO upon DHT treatment. Further, the inflammation marker, phosphorylated NF-kB p-65, was increased in the hypothalamus of Con-DHT mice. Additionally, IBA, a marker of macrophage activation was also increased upon DHT treatment in control mice. Taken together, our results suggest that while the reproductive functions are not mediated by the CNS AR, metabolic effects caused by hyperandrogenemia, is regulated by the central nervous system AR. Presentation Date: Saturday, June 17, 2023

Neuronal AR Regulates Glucose Homeostasis and Energy Expenditure in Lean Female Mice With Androgen Excess.

Hyperandrogenemia and polycystic ovary syndrome are a result of the imbalance of androgen levels in females. Androgen receptor (Ar) mediates the effect of androgen, and this study examines how neuronal Ar in the central nervous system mediates metabolism under normal and increased androgen conditions in female mice. The neuron-specific ARKO mouse (SynARKO) was created from female (Ar fl/wt; synapsin promoter driven Cre) and male (Ar fl/y) mice. A glucose tolerance test revealed impaired glucose tolerance that was partially alleviated in the SynARKO-dihydrotestosterone (DHT) mice compared with Con-DHT mice after 4 months of DHT treatment. Heat production and food intake was higher in Con-DHT mice than in Con-veh mice; these effects were not altered between SynARKO-veh and SynARKO-DHT mice, indicating that excess androgens may partially alter calorie intake and energy expenditure in females via the neuronal Ar. The pAkt/Akt activity was higher in the hypothalamus in Con-DHT mice than in Con-veh mice, and this effect was attenuated in SynARKO-DHT mice. Western blot studies show that markers of inflammation and microglia activation, such as NF-kB p-65 and IBA1, increased in the hypothalamus of Con-DHT mice compared with Con-veh. These studies suggest that neuronal Ar mediates the metabolic impacts of androgen excess in females.

Effects of early life overnutrition and hyperandrogenism on spatial learning and memory in a rat model of polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a complex disorder characterized by endocrine and metabolic abnormalities such as obesity and insulin resistance. PCOS is also associated with psychiatric disorders and cognitive impairment. The animal model of PCOS was induced by treating rats with 5α-dihydrotestosterone (5α-DHT) and additionally modified to induce adiposity by litter size reduction (LSR). Spatial learning and memory were assessed using the Barnes Maze test, and striatal markers of synaptic plasticity were analyzed. Striatal insulin signaling was estimated by the levels of insulin receptor substrate 1 (IRS1), its inhibitory phosphorylation at Ser307, and glycogen synthase kinase-3α/β (GSK3α/β) activity. Both LSR and DHT treatment significantly decreased striatal protein levels of IRS1, followed by increased GSK3α/β activity in small litters. Results of the behavioral study showed that LSR had a negative effect on learning rate and memory retention, whereas DHT treatment did not induce impairment in memory formation. While protein levels of synaptophysin, GAP43, and postsynaptic density protein 95 (PSD-95) were not altered by the treatments, DHT treatment induced an increase in phosphorylation of PSD-95 at Ser295 in both normal and small litters. This study revealed that LSR and DHT treatment suppressed insulin signaling by downregulating IRS1 in the striatum. However, DHT treatment did not have an adverse effect on learning and memory, probably due to compensatory elevation in pPSD-95-Ser295, which had a positive effect on synaptic strength. This implies that hyperandrogenemia in this setting does not represent a threat to spatial learning and memory, opposite to the effect of overnutrition-related adiposity.

AMPK Activation as a Protective Mechanism to Restrain Oxidative Stress in the Insulin-Resistant State in Skeletal Muscle of Rat Model of PCOS Subjected to Postnatal Overfeeding.

Polycystic ovary syndrome (PCOS) is a common endocrinopathy in women of reproductive age, often associated with obesity and insulin resistance. Childhood obesity is an important predisposing factor for the development of PCOS later in life. Being particularly interested in the interplay between prepubertal obesity and hyperandrogenemia, we investigated the effects of early postnatal overfeeding, accomplished by reducing litter size during the period of suckling, on energy sensing and insulin signaling pathways in the gastrocnemius muscle of a rat model of PCOS-induced by 5α-dihydrotestosterone (DHT). The combination of overfeeding and DHT treatment caused hyperinsulinemia and decreased systemic insulin sensitivity. Early postnatal overfeeding induced defects at critical nodes of the insulin signaling pathway in skeletal muscle, which was associated with reduced glucose uptake in the presence of hyperandrogenemia. In this setting, under a combination of overfeeding and DHT treatment, skeletal muscle switched to mitochondrial β-oxidation of fatty acids, resulting in oxidative stress and inflammation that stimulated AMP-activated protein kinase (AMPK) activity and its downstream targets involved in mitochondrial biogenesis and antioxidant protection. Overall, a combination of overfeeding and hyperandrogenemia resulted in a prooxidative and insulin-resistant state in skeletal muscle. This was accompanied by the activation of AMPK, which could represent a potential therapeutic target in insulin-resistant PCOS patients.

Differential Strain-dependent Ovarian and Metabolic Responses in a Mouse Model of PCOS.

Several mouse models have been developed to study polycystic ovarian syndrome (PCOS), a leading cause of infertility in women. Treatment of mice with DHT for 90 days causes ovarian and metabolic phenotypes similar to women with PCOS. We used this 90-day DHT treatment paradigm to investigate the variable incidence and heterogeneity in 2 inbred mouse strains, NOD/ShiLtJ and 129S1/SvlmJ. NOD mice naturally develop type 1 diabetes, and recent meta-analysis found increased androgen excess and PCOS in women with type 1 diabetes. The 129S1 mice are commonly used in genetic manipulations. Both NOD and 129S1 DHT-treated mice had early vaginal opening, increased anogenital distance, and altered estrus cycles compared with control animals. Additionally, both NOD and 129S1 mice had reduced numbers of corpora lutea after DHT exposure, whereas NOD mice had decreased numbers of preantral follicles and 129S1 mice had reduced numbers of small antral follicles. NOD mice had increased body weight, decreased white adipocyte size, and improved glucose sensitivity in response to DHT, whereas 129S1 mice had increased body weight and white adipocyte size. NOD mice had increased expression of Adiponectin, Cidea, Srebp1a, and Srebp1b and 129S1 mice had decreased Pparg in the white adipose tissues, whereas both NOD and 129S1 mice had increased expression of Glut4 and Prdm16, suggesting DHT may differentially affect glucose transport, thermogenesis, and lipid storage in white adipose tissue. DHT causes different ovarian and metabolic responses in NOD and 129S1 mice, suggesting that strain differences may allow further elucidation of genetic contributions to PCOS.

Physical and Natural Crosslinking Approaches on Three-Dimensional Gelatin Microspheres for Cartilage Regeneration.

The use of gelatin microspheres (GMs) as a cell carrier has been extensively researched. One of its limitations is that it dissolves rapidly in aqueous settings, precluding its use for long-term cell propagation. This circumstance necessitates the use of crosslinking agents to circumvent the constraint. Thus, this study examines two different methods of crosslinking and their effect on the microsphere's physicochemical and cartilage tissue regeneration capacity. Crosslinking was accomplished by physical (dehydrothermal [DHT]) and natural (genipin) crosslinking of the three-dimensional (3D) GM. We begin by comparing the microstructures of the scaffolds and their long-term resistance to degradation under physiological conditions (in an isotonic solution, at 37°C, pH = 7.4). Infrared spectroscopy indicated that the gelatin structure was preserved after the crosslinking treatments. The crosslinked GM demonstrated good cell adhesion, viability, proliferation, and widespread 3D scaffold colonization when seeded with human bone marrow mesenchymal stem cells. In addition, the crosslinked microspheres enhanced chondrogenesis, as demonstrated by the data. It was discovered that crosslinked GM increased the expression of cartilage-related genes and the biosynthesis of a glycosaminoglycan-positive matrix as compared with non-crosslinked GM. In comparison, DHT-crosslinked results were significantly enhanced. To summarize, DHT treatment was found to be a superior approach for crosslinking the GM to promote better cartilage tissue regeneration.

Abstract 782: Multiomic single cell sequencing identified regulatory elements in prostate cells

Abstract Introduction: Despite significant progress, the genetic role of regulatory elements in gene expression is still poorly understood in prostate cells. Recent development in single cell sequencing by combining ATAC-seq and RNA-seq has made it possible to determine genome-wide linkages between chromatin accessibilities and gene expression. Methods: To test the feasibility of using single cell multiome sequencing in dissecting regulatory linkages between chromatin accessibilities and gene expressions, we applied 10X Genomics Chromium Single Cell Multiome ATAC + Gene Expression platform to simultaneously encapsulate Tn5 transposase tagged nuclei from two prostate cell lines. We applied down-sampling linkage analysis to determine highly reproducible genome-wide associations between ATAC-seq peaks and RNA-seq gene expressions. To investigate the chromatin accessibilities related to human transcription factor binding sites, we scanned the JASPAR motif collection with genome-wide Tn5 insertion analysis. Results: This study encapsulated 3,096 multiome RWPE-1 nuclei cultured in serum-free condition, 6,978 and 8,487 multiome LNCaP nuclei treated with methanol (LNCaP-M) or dihydrotestosterone (DHT, LNCaP-D). Our analysis captured 210,990, 264,802, and 278,154 ATAC-seq peaks from RWPE-1, LNCaP-M, and LNCaP-D by macs2 narrow peak model (FDR q<0.01), which included over 90% peaks identified by bulk ATAC-seq datasets. Through downsampling linkage analysis, we identified 1,595, 2,507, and 4,183 linkage associations between ATAC-seq and RNA-seq from the above three experiments, respectively. Scatter plots showed that the correlation coefficient of the linkage association was negatively associated with the distance between ATAC-seq and RNA-seq signals. By comparing to bulk ChIP-seq data from RWPE-1 cells, we confirmed that the single cell ATAC-seq peaks in linkages were co-localized at histone modified regions, including H3K4me1 (25.7%), H3K27ac (14.3%), and H3K4me3 (4.9%). JASPAR database (634 motifs) search found that the Tn5 footprints surrounding AR, NR3C1, and NR3C2 motifs in LNCaP-D showed significantly higher enrichment than that of the LNCaP-M group, indicating increased androgen receptor DNA binding following DHT treatment. Interestingly, in RWPE-1 cells harboring TP53 p.P72R polymorphism (rs1042522), we found differential Tn5 footprints surrounding TP53 binding motif between its ATAC-seq subclusters at whole genome scale. Conclusion: Our preliminary data in prostate cell lines outlined a regulatory landscape of single-cell resolution. Multiomic single cell sequencing will help locate regulatory elements and target genes. Citation Format: Yijun Tian, Alex Soupir, Liang Wang. Multiomic single cell sequencing identified regulatory elements in prostate cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 782.

MicroRNA‐21 Genetic Ablation Exacerbates Insulin Signaling Dysregulation in Hyperandrogenemic Female Mice

IntroductionPolycystic Ovary Syndrome (PCOS) is the most common endocrine disorder in reproductive‐age women and is characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology. PCOS is associated with obesity and insulin resistance, both being risk factors associated with cardiovascular disease. Micro‐RNAs are small, non‐coding RNAs capable of altering gene expression by binding to specific mRNA targets. MicroRNA‐21(miR21) is cell‐specifically expressed and dynamically regulated in tissues that are implicated in cardiometabolic dysfunction in PCOS including the liver, skeletal muscle, and the heart. We hypothesize that miR‐21 genetic ablation exacerbates androgen‐induced dysregulation of insulin signaling to modify insulin resistance and cardiac damage in a mouse model of PCOS.MethodsThree‐week‐old peripubertal miR‐21 knockout (miR21KO) or wild‐type (WT) C57BL/6N female mice were treated s.c. with dihydrotestosterone (DHT, 8 mg) or vehicle for 90 days. Fasting glucose was determined by an enzymatic method and both fasting insulin and advanced glycation end products (AGES) were measured by ELISA. microRNA, mRNA, and protein levels were quantified by RT‐qPCR and Western‐blot. Data were analyzed by t‐test or two‐way ANOVA. All differences are considered significant p<0.05.ResultsIn WT animals DHT treatment increased miR21 expression in the soleus muscle (2.15±0.47‐fold, p<0.05), with a trend to increase in the tibialis anterior muscle (1.25‐fold), and the liver (1.41‐fold) compared with their vehicle counterparts. DHT‐treated miR21KO females showed exacerbated insulin resistance, having increased HOMA‐IR compared with both vehicle miR21KO and WT groups (6.50 ± 3.64 vs. 3.32±1.83 and 3.16±1.31, p<0.05) calculated using fasting insulin and glucose. In the soleus, miR21KO DHT‐treated mice showed an increase in Irs2 (1.45‐fold, p<0.05) compared with vehicle WT, whereas no increase was found in DHT‐treated WT animals. DHT‐treated miR21KO animals showed significantly increased Akt2 (1.40‐fold) and the glucose transporter Slc2a2 (1.24‐fold) mRNA expression in the liver. Additionally, liver protein expression of total mTOR was increased only in miR21KO DHT‐treated animals (2.40, p<0.05) compared to vehicle WT animals. Lastly, miR21KO increased left ventricular advanced glycation end products (AGEs), having significantly higher AGEs compared to all three treatment groups (3.10±0.52μg /mg protein, p<0.05).ConclusionsOur results suggest that miR21 upregulation in insulin sensitive tissues is a compensatory mechanism to counteract androgen‐inducted dysregulation of insulin signaling pathways and downstream cardiac damage. The differences observed in androgen‐treated mice highlight the potential importance of miR21 in the crosstalk between several insulin signaling networks. Notably, given the worsened DHT‐induced insulin resistance and increased left ventricular AGEs in miR21KO animals, a miR‐21 mimic may be a potential novel therapeutic option for women with PCOS.

Temporal Development of Cardiometabolic Complications in A Hyperandrogenemic Model of Polycystic Ovary Syndrome

IntroductionPolycystic Ovary Syndrome (PCOS) is the most common endocrine disorder in young women, being characterized by androgen excess and irregular ovulation. Insulin resistance (IR), dyslipidemia, obesity, and hypertension are highly prevalent in this population. The etiology of PCOS is unknown. Most patients begin developing symptoms around puberty. However, there is a delay in the diagnosis of PCOS, so the metabolic characteristics of PCOS early on are unclear. We have demonstrated in a hyperandrogenemic PCOS rat model that obesity, increases in blood pressure, and IR are present after 3 months of androgen excess. Using this model, we tested the hypothesis that androgen‐induced IR, obesity, and dyslipidemia would develop in a time‐dependent manner.MethodsFour‐week‐old Sprague Dawley female rats were randomly selected for sham or dihydrotestosterone pellet (DHT, 7.5mg/90 days) implantation (n=13‐17/group). Body composition was measured by EchoMRI; 24‐hour urine was collected with metabolic cages; and fasting plasma glucose, insulin, and lipid panel were collected at 1 (early), 2 (intermediate), and 3 (late) months of DHT treatment. IR was assessed by homeostatic model assessment for IR (HOMA‐IR).ResultsAfter 1 month of DHT, PCOS rats had decreased fasting glycemia (122.0 ± 2.8 vs 133.6 ± 3.1 mg/dL, P<0.01) and insulinemia, leading to decreased HOMA‐IR (4.3 ± 0.4 vs 7.4 ± 0.5, P<0.001). However, there were no differences between the groups in IR at 2 months of DHT, while at 3 months both fasting insulin (21.0 ± 1.6 vs 14.2 ± 1.4 µU/mL, P<0.01) and HOMA‐IR (6.3 ± 0.5 vs 4.3 ± 0.5, P<0.05) increased in PCOS compared to controls. Low‐density lipoprotein cholesterol (LDL) was increased in PCOS compared to controls at all time points, while triglycerides were only elevated at 2 months (84.9 ± 5.4 vs 65.1 ± 2.9 mg/dL, P<0.01) and 3 months (70.7 ± 5.3 vs 54.5 ± 4.5 mg/dL, P<0.05) of DHT. Meanwhile, there were no differences in high‐density lipoprotein cholesterol throughout the study. Lean mass was elevated at all time points in PCOS compared to controls, though fat mass was only elevated after 2 and 3 months (21.6 ± 1.9 vs 16.7 ± 0.8 g, P<0.05) of DHT. Proteinuria, a marker of renal injury, was elevated in PCOS at all time points.ConclusionsIn this PCOS model, early cardiometabolic complications include increases in LDL and renal injury. Intermediate cardiometabolic complications include increases in fat mass and triglyceridemia. However, DHT had a differential effect on fasting insulin and HOMA‐IR by lowering them initially at 1 month of treatment and then gradually increasing them above control levels by 3 months of DHT. These data indicate that androgen excess has a differential effect in cardiometabolic complications with time in female rats. In women with PCOS, these data may lead to a better characterization, and more effective treatments, for the evolving metabolic profile in women with PCOS.

FOXO3a-ROS pathway is involved in androgen-induced proliferation of prostate cancer cell

BackgroundAlthough FOXO3a can inhibit the cell proliferation of prostate cancer, its relationship with reactive oxygen species (ROS) in prostate cancer (PCa) has not been reported.MethodsWe analyzed the correlation between the expression of FOXO3a and the antioxidant enzyme catalase in prostate cancer with the TCGA and GEPIA databases. We also constructed a PPI network of FOXO3a via the STRING database. The mRNA and protein expression of FOXO3a and catalase were detected by qRT-PCR or western blotting in LNCaP and 22RV1 cells treated with DHT, R1881, or Enzalutamide. The effects of FOXO3a on catalase expression were tested by over-expressing or knocking down FOXO3a in LNCaP cells. Furthermore, the catalase activity and ROS level were detected in LNCaP cells treated with DHT. Cell proliferation and ROS were also analyzed in LNCaP which was treated with antioxidant.ResultsResults showed that the catalase expression was down-regulated in prostate cancer. A positive correlation between FOXO3a and catalase existed. DHT treatment could significantly reduce FOXO3a and catalase expression at mRNA and protein level in LNCaP cells. Catalase expression partly depended on FOXO3a as over-expression and knockdown of FOXO3a could result in the expresssion change of catalase. DHT treatment was found to inhibit catalase activity and increase ROS level in prostate cancer cell. Our study also demonstrated that antioxidant treatment reduced DHT-induced proliferation and ROS production in prostate cancer cell.ConclusionsWe discovered a novel mechanism by which DHT promotes prostate cancer cell proliferation via suppressing catalase activity and activating ROS signaling via a FOXO3a dependent manner.

The androgen receptor inhibits transcription of GPER1 by preventing Sp1 and Sp3 from binding to the promoters in prostate cancer cells.

G-1, a GPER1 agonist, was shown to inhibit the growth of castration-resistant mouse xenografts but not their parental androgen-dependent tumors. It is currently unknown how the androgen receptor (AR) represses GPER1 expression. Here, we found that two GPER1 mRNA variants (GPER1v2 and GPER1v4) were transcriptionally repressed, not via transcript destabilization, by the androgen-activated AR. Although no AR binding was found in all active promoters near GPER1, data from promoter assays suggested that both variants’ promoters were inhibited by androgen treatment. Site-directed mutagenesis on Sp1/Sp3 binding sites revealed their role in supporting the basal expression of GPER1. Knockdown of Sp1 and Sp3 together but not separately repressed GPER1 expression whereas overexpression of both Sp1 and Sp3 together was required to alleviate AR repression of GPER1. Based on the chromatin immunoprecipitation data, Sp3 was found to bind to the promoters prior to the binding of Sp1 and RNA polymerase II. However, the binding of all three transcription factors was inhibited by DHT treatment. Concordantly, DHT treatment induced nuclear interactions between AR and Sp1 or Sp3. Taken together, these results indicate that AR represses transcription of GPER1 by binding to Sp1 and Sp3 independently to prevent their transactivation of the GPER1 promoters.

Androgen receptor regulates eIF5A2 expression and promotes prostate cancer metastasis via EMT

Androgen receptor (AR) is an androgen-activated transcription factor of the nuclear receptor superfamily. AR plays a role in the development and progression of prostate cancer (PCa). However, the exact role of AR in PCa metastasis remains unclear. In the present study, we aimed to elucidate the function of AR in PCa. We found that eukaryotic translation initiation factor (EIF) 5A2, an elongation factor that induces epithelial-to-mesenchymal transition (EMT) in PCa cells, was significantly upregulated after 5α-dihydrotestosterone (DHT) stimulation and downregulated after anti‐androgen bicalutamide treatment in PCa cells with high AR expression, but not in cells with low AR expression. Moreover, eIF5A2 knockdown could eliminate DHT-induced invasion and migration of AR-positive PCa cells. DHT treatment decreased epithelial expression of E‐cadherin and β-catenin but increased the expression of the mesenchymal marker proteins Vimentin and N-cadherin. DHT therefore induced EMT, and knockdown of eIF5A2 inhibited DHT-induced EMT. Moreover, in vivo study, Luciferase signals from the lungs of the eIF5A2 plasmid group indicated higher metastasis ability, and the eIF5A2 siRNA group had lower metastasis ability. Our results suggest that AR positively regulates eIF5A2 expression in androgen-dependent cells, and stimulation of AR expression and signaling in prostate tumors promotes PCa metastasis by EMT induction and upregulation of eIF5A2.

Effects of Dihydrotanshinone I on Proliferation and Invasiveness of Paclitaxel-Resistant Anaplastic Thyroid Cancer Cells.

ATC is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. In patients without known genetic aberrations, the current treatment is still represented by palliative surgery and systemic mono- or combined chemotherapy, which is often not fully effective for the appearance of drug resistance. Comprehension of the mechanisms involved in the development of the resistance is therefore an urgent issue to suggest novel therapeutic approaches for this very aggressive malignancy. In this study, we created a model of anaplastic thyroid cancer (ATC) cells resistant to paclitaxel and investigated the characteristics of these cells by analyzing the profile of gene expression and comparing it with that of paclitaxel-sensitive original ATC cell lines. In addition, we evaluated the effects of Dihydrotanshinone I (DHT) on the viability and invasiveness of paclitaxel-resistant cells. ATC paclitaxel-resistant cells highlighted an overexpression of ABCB1 and a hyper-activation of the NF-κB compared to sensitive cells. DHT treatment resulted in a reduction of viability and clonogenic ability of resistant cells. Moreover, DHT induces a decrement of NF-κB activity in SW1736-PTX and 8505C-PTX cells. In conclusion, to the best of our knowledge, the results of the present study are the first to demonstrate the antitumor effects of DHT on ATC cells resistant to Paclitaxel in vitro.

Transneuronal delivery of designer cytokines: perspectives for spinal cord injury.

Transneuronal delivery of designer cytokines: perspectives for spinal cord injury.