Acetate ameliorates ovarian mitochondrial dysfunction in letrozole-induced polycystic ovarian syndrome rat model by improving mitofusin-2.

Androgen excess and metabolic abnormality largely contribute to the pathogenesis of polycystic ovarian syndrome (PCOS), which primarily precipitates ovarian dysfunction and infertility in reproductive-age women. Impaired mitochondrial function and epigenetic alteration have been linked to the development of PCOS. However, it is unknown whether acetate would exert a therapeutic effect on ovarian mitochondrial dysfunction in PCOS. Herein, the study hypothesized that acetate reverses ovarian mitochondrial dysfunction in experimental PCOS rat model, possibly through modulation of mitofusin-2 (MFn2). Eight-week-old female Wistar rats were randomized into four groups (n = 5). Induction of PCOS was performed by 1 mg/kg letrozole (p.o.), administered for 21 days. Thereafter, the rats were treated with acetate (200 mg/kg; p.o.) for 6 weeks. The PCOS rats demonstrated androgen excess, multiple ovarian cysts, elevated anti-mullerian hormone and leptin and decreased SHBG, adiponectin and 17-ß estradiol with corresponding increase in ovarian transforming growth factor-ß1. Additionally, inflammation (tumor growth factor and nuclear factor-kB), elevated caspase-6, decreased hypoxia-inducible factor-1α and elevated histone deacetylase-2 (HDAC2) were observed in the ovaries of PCOS rats, while mitochondrial abnormality with evidence of decreased adenosine triphosphate synthase and MFn2 was observed in rats with PCOS. Treatment with acetate reversed the alterations. The present results collectively suggest that acetate ameliorates ovarian mitochondrial abnormality, a beneficial effect that is accompanied by MFn2 with consequent normalization of reproductive-endocrine profile and ovarian function. Perhaps, the present data provide hope for PCOS individuals that suffer infertility.

Ribociclib plus Endocrine Therapy in Early Breast Cancer.

BACKGROUND: Ribociclib has been shown to have a significant overall survival benefit in patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer. Whether this benefit in advanced breast cancer extends to early breast cancer is unclear. METHODS: In this international, open-label, randomized, phase 3 trial, we randomly assigned patients with HR-positive, HER2-negative early breast cancer in a 1:1 ratio to receive ribociclib (at a dose of 400 mg per day for 3 weeks, followed by 1 week off, for 3 years) plus a nonsteroidal aromatase inhibitor (NSAI; letrozole at a dose of 2.5 mg per day or anastrozole at a dose of 1 mg per day for ≥5 years) or an NSAI alone. Premenopausal women and men also received goserelin every 28 days. Eligible patients had anatomical stage II or III breast cancer. Here we report the results of a prespecified interim analysis of invasive disease-free survival, the primary end point; other efficacy and safety results are also reported. Invasive disease-free survival was evaluated with the use of the Kaplan-Meier method. The statistical comparison was made with the use of a stratified log-rank test, with a protocol-specified stopping boundary of a one-sided P-value threshold of 0.0128 for superior efficacy. RESULTS: As of the data-cutoff date for this prespecified interim analysis (January 11, 2023), a total of 426 patients had had invasive disease, recurrence, or death. A significant invasive disease-free survival benefit was seen with ribociclib plus an NSAI as compared with an NSAI alone. At 3 years, invasive disease-free survival was 90.4% with ribociclib plus an NSAI and 87.1% with an NSAI alone (hazard ratio for invasive disease, recurrence, or death, 0.75; 95% confidence interval, 0.62 to 0.91; P = 0.003). Secondary end points - distant disease-free survival and recurrence-free survival - also favored ribociclib plus an NSAI. The 3-year regimen of ribociclib at a 400-mg starting dose plus an NSAI was not associated with any new safety signals. CONCLUSIONS: Ribociclib plus an NSAI significantly improved invasive disease-free survival among patients with HR-positive, HER2-negative stage II or III early breast cancer. (Funded by Novartis; NATALEE ClinicalTrials.gov number, NCT03701334.).

SNP of Aromatase Predict Long-term Survival and Aromatase Inhibitor Toxicity in Patients with Early Breast Cancer: A Biomarker Analysis of the GIM4 and GIM5 Trials.

PURPOSE: In estrogen receptor-positive (ER+) breast cancer, single-nucleotide polymorphisms (SNP) in the aromatase gene might affect aromatase inhibitors (AI) metabolism and efficacy. Here, we assessed the impact of SNP on prognosis and toxicity of patients receiving adjuvant letrozole. EXPERIMENTAL DESIGN: We enrolled 886 postmenopausal patients in the study. They were treated with letrozole for 2 to 5 years after taking tamoxifen for 2 to 6 years, continuing until they completed 5 to 10 years of therapy. Germline DNA was genotyped for SNP rs4646, rs10046, rs749292, and rs727479. Log-rank test and Cox model were used for disease-free survival (DFS) and overall survival (OS). Cumulative incidence (CI) of breast cancer metastasis was assessed through competing risk analysis, with contralateral breast cancer, second malignancies and non-breast cancer death as competing events. CI of skeletal and cardiovascular events were assessed using DFS events as competing events. Subdistribution HR (sHR) with 95% confidence intervals were calculated through Fine-Gray method. RESULTS: No SNP was associated with DFS. Variants rs10046 [sHR 2.03, (1.04-2.94)], rs749292 [sHR 2.11, (1.12-3.94)], and rs727479 [sHR 2.62, (1.17-5.83)] were associated with breast cancer metastasis. Three groups were identified on the basis of the number of these variants (0, 1, >1). Variant-based groups were associated with breast cancer metastasis (10-year CI 2.5%, 7.6%, 10.7%, P = 0.035) and OS (10-year estimates 96.5%, 93.0%, 89.6%, P = 0.030). Co-occurrence of rs10046 and rs749292 was negatively associated with 10-year CI of skeletal events (3.2% vs. 10%, P = 0.033). A similar association emerged between rs727479 and cardiovascular events (0.3% vs. 2.1%, P = 0.026). CONCLUSIONS: SNP of aromatase gene predict risk of metastasis and AI-related toxicity in ER+ early breast cancer, opening an opportunity for better treatment individualization.

Promising drug candidates for the treatment of polycystic ovary syndrome (PCOS) as alternatives to the classical medication metformin.

Polycystic ovary syndrome (PCOS) is a prevalent hormonal disorder that affects women of reproductive age. It is characterized by abnormal production of androgens, typically present in small quantities in females. This study aimed to investigate the therapeutic potential of Irosustat (STX64), STX140, and compound 1G as new drug candidates for the treatment of letrozole-induced PCOS in female Wistar rats. 36 rats were divided into six groups of equal size. PCOS was induced in all groups, except the normal control group, by administering letrozole orally (1 mg/kg/day for 35 days). The onset of abnormal estrous cycle was confirmed by examining daily vaginal smears under a microscope. Subsequently, each rat group was assigned to a different treatment regimen, including one control group, one letrozole group, one metformin group (500 mg/kg/day) as a reference drug, and the other groups received a different drug candidate orally for 30 days. After treatment, blood collection was performed for biochemical measurements and determination of oxidative stress markers. The rats were dissected to separate ovaries and uterus for morphological, histological, and western blotting studies. Treatment with the drug candidates improved the ovaries and uterus weight measurements compared to the untreated PCOS group. The three tested drug candidates demonstrated promising improvements in lipid profile, blood glucose level, testosterone, progesterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol levels. In addition, western blotting confirmed their promising effects on Akt, mTOR, and AMPK-α pathways. This study led to the discovery of three promising drug candidates for the management of PCOS as alternatives to metformin.

Expanded Access Study of Palbociclib Plus Letrozole for Postmenopausal Women with HR+/HER2- Advanced Breast Cancer in Latin America for Whom Letrozole Therapy is Deemed Appropriate.

BACKGROUND AND OBJECTIVES: Palbociclib is a cyclin-dependent kinase 4/6 inhibitor that is approved in the United States for the treatment of hormone receptor‒positive (HR+)/human epidermal growth factor receptor‒2 negative (HER2-) advanced breast cancer (ABC). The objectives of this expanded access trial were to provide palbociclib in combination with letrozole to patients with HR+/HER2- ABC in Argentina, Brazil, Colombia, and Mexico who were candidates for letrozole therapy before commercial availability of palbociclib, and to evaluate the safety and tolerability of palbociclib plus letrozole. PATIENTS AND METHODS: Postmenopausal women aged ≥ 18 years with HR+/HER2- ABC were eligible to participate in this study. Patients received palbociclib 125 mg once daily (3/1 schedule) and letrozole 2.5 mg once daily (continuous schedule). Safety, objective response rate (ORR), and duration of treatment were evaluated. RESULTS: A total of 130 patients were treated with palbociclib plus letrozole (Argentina, n = 33; Brazil, n = 35; Colombia, n = 28; Mexico, n = 34). The most common treatment-emergent adverse events (TEAEs) of any grade were neutropenia (70.0%), leukopenia (34.6%), anemia (33.8%), decreased neutrophil count (27.7%), and thrombocytopenia (24.6%); 22.3% of patients required a palbociclib dose reduction due to adverse events (AEs). Serious AEs were reported in 32 patients (24.6%). The ORR was 24.8% (95% confidence interval 17.6‒33.2), and the median duration of treatment was 10.6 months (range 0.1‒29.3). CONCLUSION: Palbociclib in combination with letrozole was generally well tolerated with a clinically manageable safety profile; the observed ORR supported treatment benefit in Latin American women with HR+/HER2- ABC. TRIAL REGISTRY: ClinicalTrials.gov, NCT02600923.

This study was done to learn more about the safety of 2 medicines together for women with advanced breast cancer after menopause. All 130 women in the study had the most common kind of breast cancer and were from Argentina, Brazil, Colombia, and Mexico. Everyone took 2 oral medicines called palbociclib and letrozole during the study. The researchers looked for any side effects experienced by the women while taking these medicines together. Another goal of the study was to see how well the treatment worked. Blood tests showed 70.0% of women had a side effect where they had a lower number of a type of white blood cell called a neutrophil. In total, 34.6% of women had low levels of another white blood cell called a leukocyte. These blood test results can mean a person is more likely to get infections. Serious side effects were experienced by 24.6% of the women, which meant these were life-threatening, caused lasting problems, or they needed hospital care. To cope with their side effects, 22.3% of the women switched to a lower palbociclib dose; 24.8% of the women had an overall response, which meant they either had a decrease in their tumor size or all cancer signs disappeared from their body. The most common length of time in the study was 10.6 months and the longest time was 29.3 months. The results of this study support using palbociclib plus letrozole to treat women who live in Latin America with advanced breast cancer after menopause.

Alleviative Effects of Adipose Tissue-derived Stem Cells and α-NETA on Metabolic, Biochemical, and Endocrine Parameters in a Letrozole-induced Rat Model of PCOS.

BACKGROUND: Polycystic ovary syndrome (PCOS), the most prevalent reproductive disorder, is accompanied by hyperandrogenism (HA), ovulatory dysfunction (OD), and insulin resistance (IR). A number of reports indicate that adipokines play a vital role in the pathophysiology of PCOS. One of these adipokines is chemerin, which is engaged in metabolic disorders, especially obesity, diabetes, and PCOS. Based on the data, the circulating levels of chemerin and the expression of chemokine-like receptor-1 (CMKLR1) in white adipose tissue (WAT) of women with PCOS are significantly higher than in healthy ones. Currently, several scholars have emphasized the therapeutic capacities of stem cells, notably mesenchymal stem cells (MSCs), for the treatment of PCOS. OBJECTIVE: In this study, for the first time, the impacts of 2-(α-naphthoyl) ethyltrimethylammonium iodide (α- NETA), an antagonist of CMKLR1, adipose-derived stem cells (ADSCs), and their combinations on metabolic and endocrine aberrancies were assessed in the WAT and ovarian tissues of the letrozole (LET)-induced PCOS rats. METHODS: In the current study, 30 Wistar rats were randomly divided into five groups: control (n = 6), LET-induced PCOS (1.5 mg/kg p.o., n = 6), LET + ADSCs (106 ADSCs i.v., n = 6), LET + α-NETA (10 mg/kg p.o., n = 6), and LET + ADSCs + α-NETA (n = 6). The blood samples and adipose and ovarian tissues were obtained to evaluate the effects of ADSCs and α-NETA on hormonal and metabolic parameters in the PCOS rats. RESULTS: Our findings showed that the administration of α-NETA, ADSCs, and the combination of both favorably restored the irregular estrus cycle and considerably modulated the endocrine parameters in PCOS rats. In addition, these therapeutic factors remarkably regulated steroidogenic and adipogenic gene expressions, as well as the genes related to glucose metabolism and brown adipose tissue (BAT) markers in these animals. CONCLUSION: These findings indicate that the combination of ADSCs and α-NETA can successfully ameliorate metabolic and endocrine dysfunction in LET-induced PCOS rats, and this strategy could be a new therapeutic choice for patients with PCOS.

Single-cell sequencing provides insights into the landscape of ovary in PCOS and alterations induced by CUMS.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder related to psychological distress. However, the mechanism underlying increased prevalence of depression in PCOS remained unclear. This study aimed to explore the unique transcriptional landscape of ovary and offered a platform to explore the mechanism of PCOS, as well as the influences caused by depression. The PCOS rat model was established by letrozole whereas PCOS rat model with depression was established by letrozole combined with chronic unpredicted mild stress (CUMS). Then single-cell RNA sequencing (scRNA-Seq) was applied to analyze the transcriptional features of rat ovaries. Granulosa cells (GCs) and fibroblasts (Fibros) accounted for the top two clusters of total 12 cell types. There were nine clusters in GCs, related to inflammatory response, endoplasmic reticulum (ER) stress, and steroidogenesis. The expression of differentially expressed genes (DEG) Hes1 was higher in PCOS and PCOS + CUMS groups, exhibiting enhanced expression by pseudotime and positively related to inflammation. Pseudotemporal analysis revealed that inflammation contributed to the different GCs distributions. Moreover, analysis of DEGs and gene ontology (GO) function enrichment revealed CUMS aggravated inflammation in PCOS GCs possibly via interferon signaling pathway. In theca cells (TCs), nine clusters were observed and some of them were relevant to inflammation, ER stress, and lipid metabolism. DEGs Ass1, Insl3, and Ifi27 were positively related to Cyp17a1, and Ces1d might contribute to the different trajectory of TCs. Subsequent scRNA-seq revealed a signature profile of endothelial cells (ECs) and Fibros, which suggest that inflammation-induced damage of ECs and Fibro, further exacerbated by CUMS. Finally, analysis of T cells and mononuclear phagocytes (MPs) revealed the existence of immune dysfunction, among which interferon signaling played a critical role. These findings provided more knowledge for a better understanding PCOS from the view of inflammation and identified new biomarkers and targets for the treatment of PCOS with psychological diseases.NEW & NOTEWORTHY In this study, we mapped the landscape of polycystic ovary syndrome (PCOS) ovary with rat model induced by letrozole and provided a novel insight into the molecular mechanism of PCOS accompanied by chronic unpredicted mild stress (CUMS) at single-cell transcriptomic level. These observations highlight the importance of inflammation in the pathogenesis of PCOS, which might also be the bridge between PCOS and psychological diseases.

Therapeutic potential of icariin in rats with letrozole and high-fat diet-induced polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is characterized by reproductive, endocrine, and metabolic disorders. Icariin has been shown to regulate endocrine and metabolic imbalances. This study aimed to determine the therapeutic effect and pharmacological mechanism of icariin in PCOS rats. Rats were fed a high-fat diet and gavaged with letrozole to induce PCOS. Thirty-six female rats were randomly divided into four groups: control, model, low-dose, and high-dose icariin. After 30 days of treatment, we evaluated the therapeutic effects on weight and diet, sex hormone levels, ovarian morphology, estrous cycle, inflammatory factors, and indicators of glucolipid metabolism. Combined with the ovarian transcriptome, we verified the key markers of apoptosis and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway by RT-qPCR for mRNA level, western blot, and immunohistochemistry for protein expression. Icariin significantly improved ovarian function and reproductive endocrine disorders by regulating sex hormones, restoring the estrous cycle, and reducing ovarian morphological damage in PCOS rats. Icariin-treated rats had lower weight gain and reduced triglycerides, fasting insulin, HOMA-IR, TNF-α, and interleukin-6 with higher high-density lipoprotein cholesterol levels than PCOS rats. TUNEL staining showed icariin improved apoptosis in the ovaries. This was supported by an increase in Bcl2 and a decrease in Bad and Bax. Icariin decreased the ratios of p-JAK2/JAK2, p-STAT1/STAT1, p-STAT3/STAT3, and p-STAT5a/STAT5a, decreased IL-6, gp130 expression, and increased cytokine-inducible SH2-containing protein (CISH) and suppressor of cytokine signaling 1 (SOCS1) expression. The pharmacological mechanism may be related to the reduction in ovarian apoptosis and inhibition of the IL-6/gp130/JAK2/STATs pathway.

Effect of Parquetina nigrescens (Afzel.) Leaves on Letrozole-Induced PCOS in Rats: a Molecular Insight into Its Phytoconstituents.

Polycystic ovarian syndrome (PCOS) is one of the common causes of female infertility in women of reproductive age. P. nigrescens is a plant used in the treatment of various diseases including menstrual disorders. This study investigated the effect of ethanolic extracts of P. nigrescens leaves on the estrous cycle, fasting blood glucose, and hormonal and lipid profile in letrozole-induced PCOS rats and also evaluated the molecular mechanism of the active constituents using computational methods. After the induction of PCOS with letrozole, rats were treated orally for 14 days with distilled water (1 mg/kg/day), clomiphene citrate (2 mg/kg/day), metformin (7.14 mg/kg/day), and ethanolic extract of P. nigrescens (50 and 100 mg). Thereafter, selected biochemical parameters were assayed to determine the extract's effect on the estrous cycle. Molecular docking and molecular dynamics simulation (MDS) were carried out to determine the binding affinity and relative stability of the ligand-receptor complexes. Letrozole-induced PCOS rats showed irregular estrous cyclicity, elevated (p > 0.05) triglycerides, low-density lipoprotein cholesterol (LDL), total cholesterol, insulin, testosterone, and luteinizing hormone (LH) concentration, low (p > 0.05) progesterone, low follicle-stimulating hormone (FSH), high-density lipoprotein cholesterol (HDL), and high fasting blood glucose concentration compared to that of the control group. The reproductive, biochemical, and structural alterations were reversed by the administration of ethanolic extract of P. nigrescens leaves (50 mg/kg) which restored the estrous cycle after 14 days of treatment. However, the ethanolic extracts of P. nigrescens (100 mg/kg) significantly increased (p > 0.05) FSH, HDL, and progesterone concentrations but decreased the LH, progesterone, and total cholesterol. Of all 44 compounds identified in GCMS analysis of an ethanolic extract of P. nigrescens leaves, only 2-ethylbutyl heptyl ester (CID 91705405) had a higher binding affinity for hormonal receptors and enzymes responsible for hepatic gluconeogenesis compared to standard drugs used in the study. CID 91705405 was also relatively stable over 100 ns of MDS. This compound is therefore revealed to have the potential to modulate both endocrine and metabolic pathways involved in PCOS. The ethanolic extract of P. nigrescens leaves can therefore be considered in the management/treatment of the reproductive and metabolic disorders related to PCOS subject to further experimental validation.

Letrozole-induced inflammatory arthritis and tendinopathy in pediatric rheumatology setting.

Musculoskeletal symptoms associated with the use of aromatase inhibitors are a well-known side effect of these drugs and are more prevalent in postmenopausal women. Aromatase inhibitor-associated symptoms are not overt inflammatory processes so are described as arthralgia syndrome. In contrast, aromatase inhibitor-associated inflammatory conditions such as myopathies, vasculitis, and rheumatoid arthritis were also reported. To our knowledge, inflammatory arthritis or tendinopathy associated with aromatase inhibitors were not reported in children despite their increased off-label use in the pediatric setting. Herein, we report a girl with inflammatory arthritis and tendinopathy associated with letrozole treatment.

Naringenin improves ovarian health by reducing the serum androgen and eliminating follicular cysts in letrozole-induced polycystic ovary syndrome in the Sprague Dawley rats.

Polycystic ovary syndrome (PCOS) is most common in women of reproductive age, giving rise to androgen excess and anovulation, leading to infertility and non-reproductive complications. We explored the ameliorating effect of naringenin in PCOS using the Sprague Dawley (SD) rat model and human granulosa cells. Letrozole-induced PCOS rats were given either naringenin (50 mg/kg/day) alone or in combination with metformin (300 mg/kg/day), followed by the estrous cycle, hormonal analysis, and glucose sensitivity test. To evaluate the effect of naringenin on granulosa cell (hGC) steroidogenesis, we treated cells with naringenin (2.5 µM) alone or in combination with metformin (1 mM) in the presence of forskolin (10 µM). To determine the steroidogenesis of CYP-17A1, -19A1, and 3ßHSD2, the protein expression levels were examined. Treatment with naringenin in the PCOS animal groups increased ovulation potential and decreased cystic follicles and levels of androgens. The expression levels of CYP-17A1, -19A1, and 3ßHSD2, were seen restored in the ovary of PCOS SD rats' model and in the human ovarian cells in response to the naringenin. We found an increased expression level of phosphorylated-AKT in the ovary and hGCs by naringenin. Naringenin improves ovulation and suppress androgens and cystic follicles, involving AKT activation.

Role of diacerein on steroidogenesis and folliculogenesis related genes in ovary of letrozole-induced PCOS mice.

Polycystic ovary syndrome (PCOS), an intricate and multifaceted metabolic-endocrine disorder that typically affects 6-20% of women of reproductive age and accounts for 70-80% of all occurrences of infertility globally. In this study we focussed on the effect of diacerein (DIC) on steroidogenesis and follicle development in addition to the basic metabolic and endocrine problems which are associated with PCOS. Eighteen mature female parkes strain mice were separated into three groups at random with 6 animals in a group as follows: Group I, received water and normal diet for 66 days; group II received letrozole (LETZ) (6 mg/kg bw) for the induction of PCOS; Group III received LETZ (6 mg/kg) for 3 weeks followed by the administration of DIC (35 mg/kg) for 45 days. In our study we observed that mice with PCOS had irregular estrous cycle with increased LH/FSH, estrogen level and decline in expression of Kitl, Bmp, Cyp11a1, CYP19a1, Ar, lhr, Fshr and Esr1 as well as decreased SOD and CAT activity in ovary. Moreover, we observed increase in the expression of CYP17a1, as well as increase in serum cholesterol, triglycerides, testosterone, LH, VEGF and insulin levels. All these changes were reversed after the administration of DIC in PCOS mice. Diacerin administration reversed abnormalities in mice with PCOS by modulating the regulation of genes which are related to steroidogenesis and folliculogenesis.

Variations in Incidence of Trigger Finger and Response to Corticosteroid Injection after Aromatase Inhibitor Therapy for Breast Cancer.

BACKGROUND: Aromatase inhibitors (AIs), such as letrozole and anastrozole, have been demonstrated to have significant musculoskeletal symptoms in patients. The purpose of this study was to evaluate the effect of specific AI medications on the incidence of trigger finger and independent factors affecting treatment outcomes within this population. METHODS: A retrospective chart review was performed at the authors' institution between the years 2014 and 2018 in patients with the diagnosis of breast cancer. This cohort was then sorted based on receiving medication regimens, trigger finger diagnosis, steroid injections, and need for surgical release of trigger finger. RESULTS: A total of 15,144 patients were included for initial review. The overall rate of trigger finger diagnosis was 2.75% in the entire breast cancer population and 4.5% for patients receiving AI therapy. Patients taking letrozole and anastrozole had an increased odds ratio of 2.0 and 1.7, respectively, for developing trigger finger. Patients who switched between letrozole and anastrozole during treatment had a higher rate of failed steroid injection treatment (45.2% versus 23.5%; P = 0.021). Among patients receiving AI treatment diagnosed with trigger finger, diabetes and hemoglobin A1c level greater than 6.5 were associated with significantly increased rates of failed steroid therapy. CONCLUSIONS: Patients receiving AI therapy have an increased incidence of trigger finger. The outcomes of treatment are equivalent between AI and non-AI trigger finger populations. However, steroid therapy is more likely to fail in patients who require switching of regimens because of significant musculoskeletal symptoms. Poorly controlled diabetes was also an independent factor for compromised steroid treatment of trigger finger. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Ameliorative effect of sesame oil on experimentally induced polycystic ovary syndrome: A cross-link between XBP-1/PPAR-1, regulatory proteins for lipogenesis/steroids.

Polycystic ovary syndrome (PCOS) is a mixed endocrine/metabolic/reproductive disorder in women of reproductive age. Sesame oil (SO) contains sesame lignans & vitamin E with broad-spectrum antioxidant and anti-inflammatory effects. This study investigates the ameliorative effect of SO on experimentally induced PCOS and elucidates the possible molecular mechanisms with a deeper focus on the different signaling pathways involved. The study was carried out on 28 nonpregnant female Wister albino rats that were divided into four equal groups; Group I (control group) received oral 0.5% wt/vol carboxymethyl cellulose daily. Group II (SO group): orally administered SO (2 mL/kg body wt./day) for 21 days. Group III (PCOS group) received letrozole daily, 1 mg/kg, for 21 days. Group IV (PCOS + SO group): concomitantly administered letrozole and SO for 21 days. The serum hormonal and metabolic panel and the homogenate ATF-1, StAR, MAPK, PKA, and PI3K levels of the ovarian tissue were calorimetrically evaluated. However, endoplasmic reticulum (ER) stress was evaluated by ovarian XBP1 and PPAR-γ messenger RNA expression level using the qRT-PCR technique. Ovarian COX-2 was detected immunohistochemically. The results suggest that SO-treated PCOS rats showed a significantly improved hormonal, metabolic panel, inflammatory, and ER stress status with concomitant decreases in ATF-1, StAR, MAPK, PKA, and PI3K in ovarian rats compared to the correspondent values in PCOS without treatment. CONCLUSIONS: The protective effects of SO against PCOS are triggered by ameliorating regulatory proteins of ER stress, lipogenesis, and steroidogenesis through the PI3K/PKA and MAPK/ERK2 signaling cascades. SIGNIFICANCE STATEMENT: Polycystic ovary syndrome (PCOS) is the most common mixed endocrine-metabolic dysfunction among women within the reproductive period, with an estimated prevalence of 5%-26% worldwide. Doctors traditionally recommend metformin for PCOS patients. However, metformin is known to be associated with significant adverse effects and contraindications. This work aimed at shedding light on the ameliorative effect of sesame oil (SO), natural polyunsaturated fatty acids-rich oil, on the induced PCOS model. SO proved to have a marvelous effect on the metabolic and endocrine derangements in the PCOS rat model. We hoped to provide a valuable alternative treatment for PCOS patients to avoid the side effects of metformin and to help PCOS patients for whom metformin is contraindicated.

Therapeutic Potential of Selenium Nanoparticles on Letrozole-Induced Polycystic Ovarian Syndrome in Female Wistar Rats.

Polycystic ovarian syndrome (PCOS) is considered the most frequent gynecological endocrine disorder that causes anovulatory infertility. The current study aimed to investigate the potential significance of selenium nanoparticles (SeNPs), an IL-1 inhibitor, in the treatment of letrozole-induced PCOS in rats that satisfied the metabolic and endocrine parameters found in PCOS patients. Letrozole (2 ppm, per orally, p.o.) was given orally to female Wistar rats for 21 days to develop PCOS. After PCOS induction, rats were given SeNPs (25 ppm/day, p.o.), SeNPs (50 ppm/day, p.o.), or metformin (2 ppm/day, p.o.) for 14 days. PCOS was associated with an increase in body weight, ovarian weight, ovarian size, and cysts, as well as an increase in blood testosterone, luteinizing hormone (LH), and insulin, glycaemia, and lipid profile levels. The SeNP administration decreased all of these variables. Furthermore, SeNPs significantly reduced letrozole-induced oxidative stress in the ovaries, muscles, and liver by decreasing elevated levels of malondialdehyde and total nitrite while raising suppressed levels of superoxide dismutase and catalase. SeNPs increased the amounts of the protective proteins Kelch-like ECH-associated protein 1 (Keap-1), nuclear factor erythroid 2-related factor 2 (Nrf2), and OH-1. It was depicted from the study that SeNPs reduce the upregulation of inflammatory cytokines that are interleukin 6 (IL-6), tumour necrosis factor α (TNF-α), and the interleukin 1 (IL-1). Our findings show that SeNPs, through their antioxidant and anti-inflammatory characteristics, alleviate letrozole-induced PCOS.

Milicia excelsa (Moraceae) reversed the effects of letrozole-induced aromatase inhibition in rats with polycystic ovary syndrome.

OBJECTIVES: Polycystic ovary syndrome (PCOS) is an endocrinopathy affecting 5-20% of women of childbearing age. There is no single drug for the treatment of PCOS and current therapies have significant side effects. This study evaluated the ability of Milica excelsa to improve PCOS symptoms in rats. METHODS: Induction of PCOS was achieved using letrozole (a reversible aromatase inhibitor; 1 mg/kg; given orally for 21 days). From day 22, PCOS rats received the aqueous extract of M. excelsa roots (14 and 140 mg/kg). Clomiphene citrate (1 mg/kg) was administered to the positive control. The negative and the normal controls received the vehicle (5% DMSO). Treatments were given orally for 7 or 14 days. Vaginal smears were scrutinized daily during the experiment. Body weight was measured hebdomadal. Animals were sacrificed after the two treatment periods for biochemical and histological analyses. RESULTS: Aromatase inhibition caused hyperandrogenism (p<0.001), overweight (p<0.001) and fat accumulation (p<0.001). It also blocked the estrous cycle at the diestrus phase and altered ovarian dynamics as evidenced by the accumulation of cystic (p<0.001) and atretic (p<0.001) follicles. In contrast, M. excelsa induced weight loss (p<0.001), reduction in fat weight (p<0001), and lower serum androgen and LH levels (p<0.001). It also restored the estrous cycle and improved ovarian dynamics by increasing the amount of Graafian follicles (p<0.001) and corpora lutea (p<0.001), and decreasing that of cystic and atretic follicles (p<0.001). CONCLUSIONS: Milica excelsa corrected hyperandrogenism and overweight in PCOS animals, and reduced cyst formation and follicle atresia in their ovaries.

Influence of the anti-oestrogens tamoxifen and letrozole on thyroid function in women with early and advanced breast cancer: A systematic review.

INTRODUCTION: Breast cancer (BC) is a common type of cancer in women. Advances in therapy options have resulted in higher overall survival rates but side effects of cancer treatment are increasingly in the spotlight. The beneficial effects of anti-oestrogen therapy with tamoxifen and letrozole in the prevention of BC recurrence are well documented. While the most common side-effects of this therapy are well-defined, less is known about its effects on thyroid function. In women treated for early BC, an average of 1-5 kg weight gain has been observed after treatment with chemotherapy/anti-oestrogens. We aim to evaluate the current knowledge on the side effects of tamoxifen and letrozole treatments on thyroid function, followed by its potential influence on the observed weight gain. METHODS: We searched PubMed and found 16 publications on thyroid function and tamoxifen treatment in pre- and post-menopausal women with early- and advanced BC, whereas five publications on letrozole treatment in post-menopausal women with advanced BC. RESULTS: According to the current literature, there is an overall tendency towards a mild and transient thyroid dysfunction, that is, subclinical hypothyroidism in tamoxifen-treated patients. Only one publication reported further significant changes in thyroid hormones beyond one year of tamoxifen treatment. No significant changes in thyroid function have been observed among letrozole-treated patients. CONCLUSION: Tamoxifen-treated patients can develop mild and transient thyroid dysfunction within the first 12 months, yet further significant changes in thyroid function beyond one year of tamoxifen treatment have been reported in a single study. There is no evidence of thyroid dysfunction in letrozole-treated patients. Current literature does not focus on subclinical hypothyroidism as a possible cause of weight gain in patients with BC. Subgrouping of BC patients and studies with a longer observation of thyroid hormones and weight changes during and after anti-oestrogen treatment are needed to further elucidate how anti-oestrogens affect thyroid function.

Letrozole ameliorates liver fibrosis through the inhibition of the CTGF pathway and 17ß-hydroxysteroid dehydrogenase 13 expression.

BACKGROUND: To establish a treatment option for liver fibrosis, the possibility of the drug repurposing theory was investigated, with a focus on the off-target effects of active pharmaceutical ingredients. METHODS: First, several active pharmaceutical ingredients were screened for their effects on the gene expression in the hepatocytes using chimeric mice with humanized hepatocytes. As per the gene expression-based screening assay for 36 medications, we assessed the mechanism of the antifibrotic effect of letrozole, a third-generation aromatase inhibitor, in mouse models of liver fibrosis induced by carbon tetrachloride (CCl4) and a methionine choline-deficient (MCD) diet. We assessed liver histology, serum biochemical markers, and fibrosis-related gene and protein expressions in the hepatocytes. RESULTS: A gene expression-based screening assay revealed that letrozole had a modifying effect on fibrosis-related gene expression in the hepatocytes, including YAP, CTGF, TGF-ß, and CYP26A1. Letrozole was administered to mouse models of CCl4- and MCD-induced liver fibrosis and it ameliorated the liver fibrosis. The mechanisms involved the inhibition of the Yap-Ctgf profibrotic pathway following a decrease in retinoic acid levels in the hepatocytes caused by suppression of the hepatic retinol dehydrogenase, Hsd17b13 and activation of the retinoic acid hydrogenase, Cyp26a1. CONCLUSIONS: Letrozole slowed the progression of liver fibrosis by inhibiting the Yap-Ctgf pathway. The mechanisms involved the modification of the Hsd17b13 and Cyp26a1 expressions led to the suppression of retinoic acid in the hepatocytes, which contributed to the activation of Yap-Ctgf pathway. Because of its off-target effect, letrozole could be repurposed for the treatment of liver fibrosis. The third-generation aromatase inhibitor letrozole ameliorated liver fibrosis by suppressing the Yap-Ctgf pathway by partially modifying the Hsd17b13 and Cyp26a1 expressions, which reduced the retinoic acid level in the hepatocytes. The gene expression analysis using chimeric mice with humanized liver revealed that the mechanisms are letrozole specific and, therefore, may be repurposed for the treatment of liver fibrosis.

Protective Role of Acetate Against Depressive-Like Behaviour Associated with Letrozole-Induced PCOS Rat Model: Involvement of HDAC2 and DNA Methylation.

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder amongst women of reproductive age. PCOS has been demonstrated to induce depressive-like behaviour. Epigenetic alterations such as histone deacetylation (HDAC) and DNA methylation have been suggested in major depression. However, their effects with respect to neuroinflammation are not clear. This study therefore investigated the pathogenic involvement of epigenetic changes in PCOS-associated depression and the protective role of HDACi, especially acetate. Virgin female Wistar rats (140 ± 10 g) were assigned into four groups: the groups received vehicle (control), acetate (200 mg/kg), letrozole (1 mg/kg) and letrozole plus acetate, respectively. The administrations were done concomitantly by oral gavage for 21 days. Treatment with letrozole caused hyperandrogenism, hypoestrogenism, hyperinsulinemia and multiple ovarian cysts/degenerated follicles. In addition, these animals showed depressive-like behaviours and increased expression of HDAC2 and DNA methyltransferase in PFC and hippocampal tissues. Biochemical analyses showed elevated levels of NF-κB, malondialdehyde and acetylcholine (ACH) with glutathione depletion in PFC and hippocampus as well as elevated plasma malondialdehyde and impaired anti-oxidant system in letrozole-treated animals. Histological analysis of PFC and hippocampus showed neurodegeneration in letrozole-treated animals compared with control. However, these alterations were attenuated when treated with acetate. The study demonstrates that PCOS-associated depression is characterised by neuroinflammation and elevated ACH levels, accompanied by increased expression of HDAC2/DNA methyltransferase in PFC and hippocampus. Besides, the study suggests that acetate protects against PCOS-associated depression through suppression of prefrontal and hippocampal DNA methylation and prefrontal but not hippocampal HDAC2 expression.

Ketogenic diet restores hormonal, apoptotic/proliferative balance and enhances the effect of metformin on a letrozole-induced polycystic ovary model in rats.

OBJECTIVE: Polycystic ovaries (PCO) is a hormonal disorder that is a leading cause of infertility. The formation of multiple persistent cysts and hormonal imbalance are hallmarks of PCO. Recent clinical studies reported a beneficial effect of the ketogenic diet (KD; high-fat, low-carbohydrate) on PCO. The aim of this study was to investigate the effect of the KD alone and in combination with metformin on letrozole-induced PCO in female rats. METHODS: Female rats were grouped into control and PCO (letrozole; 1 mg/kg for 21 days). The PCO group was subdivided into PCO (non-treated), PCO-metformin (300 mg/kg), PCO rats fed with KD only, and PCO rats treated with metformin and fed with KD. All groups continued to receive letrozole during the 21-day treatment period. At the end of the experiment, serum and ovaries were collected for further analysis. RESULTS: The untreated-PCO rats showed increased testosterone, LH/FSH ratio, and ovary weights. Disturbed apoptosis and proliferation balance were evident as a low caspase-3 activation and proliferating cell nuclear antigen expression and increased TGF-ß expression. The KD improved the letrozole-induced effects, which was comparable to the effect of metformin. Combining the KD with metformin treatment additively enhanced the metformin effect. CONCLUSION: Our results indicate that the KD has a protective role against PCO in rats, especially when combined with metformin. This study reveals a potential therapeutic role of the KD in PCO, which could prompt valuable future clinical applications.