Effects of genistein on oestrogen and progesterone receptor, proliferative marker Ki-67 and carbonic anhydrase localisation in the uterus and cervix of gilts after insemination

Immunohistochemical Expression (IE) of Oestrogen Receptors in the Intestines of Prepubertal Gilts Exposed to Zearalenone

This study was conducted to determine if a low monotonic dose of zearalenone (ZEN) affects the immunohistochemical expression (IE) of oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERβ) in the intestines of sexually immature gilts. Group C (control group; n = 18) gilts were given a placebo. Group E (experimental group; n = 18) gilts were dosed orally with 40 μg ZEN /kg body weight (BW), each day before morning feeding. Samples of intestinal tissue were collected post-mortem six times. The samples were stained to analyse the IE of ERα and Erβ in the scanned slides. The strongest response was observed in ERα in the duodenum (90.387-average % of cells with ERα expression) and in ERβ in the descending colon (84.329-average % of cells with ERβ expression); the opposite response was recorded in the caecum (2.484-average % of cells with ERα expression) and the ascending colon (2.448-average % of cells with ERα expression); on the first two dates of exposure, the digestive tract had to adapt to ZEN in feed. The results of this study, supported by a mechanistic interpretation of previous research findings, suggest that ZEN performs numerous functions in the digestive tract.

The immunolocalization of HIF-2α, GLUT1 and CAIX in porcine oviduct during the estrous cycle

Oxygen (O₂ ) rates in the oviduct are essential to human and animal reproduction. These rates are regulated by the activity of hypoxia markers such as the hypoxia-inducible factors (HIFs), the glucose transporters (GLUT), and the carbonic anhydrase (CA). In the porcine model, scarce studies have been reported regarding these markers and their effects in reproduction are unknown. The objective was to characterize the immunolocalization of HIF-2α, GLUT1, and CAIX in porcine oviducts throughout the estrous cycle. Oviducts (ampulla and isthmus) of adult sows (n = 45) were collected for histological and immunohistochemical analysis with HIF-2α, GLUT1, and CAIX markers. The percentage of immunopositive area was quantified, and the differences among phases of the estrous cycle were analyzed (folicular, early luteal, and late luteal). The three markers showed epithelial presence mainly. Significantly lower expression of HIF-2α was found in the luteal phases, especially in the isthmus. GLUT1 expression did not change throughout the estrous cycle, but differences were found between the ampulla and isthmus. CAIX expression showed the highest, with a significant downward trend throughout estrous cycle. The ubiquitous expression of hypoxia markers shows the porcine oviduct physiology in relation to O₂ . The differential expression of HIF-2α, GLUT1, and CAIX in different subcompartments of the oviduct throughout the estrous cycle contributes to improve the knowledge of the cell physiology of the oviduct, which can be useful in fertilization studies.

Prunetin inhibits nitric oxide activity and induces apoptosis in urinary bladder cancer cells via CASP3 and TNF-α genes

BACKGROUND

Urinary bladder cancer (UBC) is considered one of the most prevalent malignant tumors worldwide. Complementary and integrative approaches for the treatment of bladder cancer, such as the intake of isoflavonoid phytoestrogens, are of increasing interest due to the risk of mortality and long-term morbidity associated with surgical procedures. The biological effects of prunetin, one of the less-studied phytoestrogens, have not yet been examined in this respect. Therefore, this study aimed to explore the efficacy of prunetin on UBC cells (RT-4). METHODS AND RESULTS: The cytotoxicity and nitric oxide synthase activities of prunetin were determined in cell cultures. The expression of apoptosis-related genes was determined with RT-PCR. Cell cycle assays were performed using a flow cytometer and cellular apoptotic rate was measured. The results suggested that prunetin has cytotoxic effects at 21.11 µg/mL on RT-4 cells. Flow cytometry analysis showed that prunetin induced apoptosis and arrested th cell cycle in the G₀/G₁ phase. Prunetin exposure was associated with increases in CASP3 and TNF-α gene expression in RT-4 cells at doses of 21.11 and 42.22 µg/mL, respectively. Strong nitric oxide inhibition was observed at IC₅₀ of 5.18 µg/mL under macrophage mediated inflammatory circumstances.

CONCLUSIONS

Prunetin possesses anti-cancer properties and may be a candidate compound for the prevention of UBC. This is the first study that evaluated prunetin for its in vitro antitumor activities, clarified its possible apoptotic molecular mechanism and provided novel insights into its anti-inflammatory nature and effects on the expression of related key genes.

Correlations between exposure to deoxynivalenol and zearalenone and the immunohistochemical expression of estrogen receptors in the intestinal epithelium and the mRNA expression of selected colonic enzymes in pre-pubertal gilts

Plant-based materials used in the production of pig feed are very often contaminated with deoxynivalenol and zearalenone. Daily intake of small amounts of these mycotoxins with feed induces various subclinical states in gilts and influences different biological processes. The aim of this preclinical study was to determine the correlation between monotonic doses of zearalenone and deoxynivalenol (40 μg/kg body weight and 12 μg/kg body weight, respectively, administered over a period of 42 days) and the immunohistochemical expression of estrogen receptors in the intestinal tract and the mRNA expression of selected colonic enzymes. The immunohistochemical expression of estrogen receptor alpha was observed in the colon, but its intensity varied in different weeks of exposure. A minor increase in estrogen receptor beta expression was noted only in the colon, whereas the expression of cytochrome P450 1A1 enzyme mRNA and mRNA isoform of the glutathione S-transferase π gene decreased. The observed correlations suggest that the risk of loss of control over the biotransformation and biological activity of the parent compounds in distal intestinal mucosa is delayed.

Combinatorial Epigenetics Impact of Polyphenols and Phytochemicals in Cancer Prevention and Therapy

Polyphenols are potent micronutrients that can be found in large quantities in various food sources and spices. These compounds, also known as phenolics due to their phenolic structure, play a vital nutrient-based role in the prevention of various diseases such as diabetes, cardiovascular diseases, neurodegenerative diseases, liver disease, and cancers. However, the function of polyphenols in disease prevention and therapy depends on their dietary consumption and biological properties. According to American Cancer Society statistics, there will be an expected rise of 23.6 million new cancer cases by 2030. Due to the severity of the increased risk, it is important to evaluate various preventive measures associated with cancer. Relatively recently, numerous studies have indicated that various dietary polyphenols and phytochemicals possess properties of modifying epigenetic mechanisms that modulate gene expression resulting in regulation of cancer. These polyphenols and phytochemicals, when administrated in a dose-dependent and combinatorial-based manner, can have an enhanced effect on epigenetic changes, which play a crucial role in cancer prevention and therapy. Hence, this review will focus on the mechanisms of combined polyphenols and phytochemicals that can impact various epigenetic modifications such as DNA methylation and histone modifications as well as regulation of non-coding miRNAs expression for treatment and prevention of various types of cancer.

Phytochemicals as Modulators of Long Non-Coding RNAs and Inhibitors of Cancer-Related Carbonic Anhydrases

Long non-coding RNAs (lncRNAs) are classified as a group of transcripts which regulate various biological processes, such as RNA processing, epigenetic control, and signaling pathways. According to recent studies, lncRNAs are dysregulated in cancer and play an important role in cancer incidence and spreading. There is also an association between lncRNAs and the overexpression of some tumor-associated proteins, including carbonic anhydrases II, IX, and XII (CA II, CA IX, and CA XII). Therefore, not only CA inhibition, but also lncRNA modulation, could represent an attractive strategy for cancer prevention and therapy. Experimental studies have suggested that herbal compounds regulate the expression of many lncRNAs involved in cancer, such as HOTAIR (HOX transcript antisense RNA), H19, MALAT1 (metastasis-associated lung adenocarcinoma transcript 1), PCGEM1 (Prostate cancer gene expression marker 1), PVT1, etc. These plant-derived drugs or phytochemicals include resveratrol, curcumin, genistein, quercetin, epigallocatechin-3-galate, camptothcin, and 3,3′-diindolylmethane. More comprehensive information about lncRNA modulation via phytochemicals would be helpful for the administration of new herbal derivatives in cancer therapy. In this review, we describe the state-of-the-art and potential of phytochemicals as modulators of lncRNAs in different types of cancers.

Bacillus licheniformis CK1 alleviates the toxic effects of zearalenone in feed on weaned female Tibetan piglets

Zearalenone (ZEA) is widely present in feedstuffs and raw materials, causing reproductive disorders in animals. In this study, Bacillus licheniformis CK1 was used to detoxify ZEA in feed for alleviating its effect in Tibetan piglets. A total of 18 weaned female Tibetan piglets were randomly divided into 3 groups: control group (Control, ZEA-free basal diet); treatment group 1 (T1, ZEA-contaminated diet); and treatment group 2 (T2, ZEA-contaminated but pre-fermented by CK1 diet). There were no significant differences of average daily feed intake (ADFI), average daily gain (ADG), and feed efficiency (FE) among the 3 groups (P > 0.05). The T1 treatment significantly increased the vulva size and relative weight of the reproductive organ (P < 0.05), compared with the Control. However, the T2 treatment caused a significant reduction (P < 0.05) in vulva size and relative weight of the reproductive organ compared with the T1 group. The levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P), and estradiol (E2) in the T1 group were significantly lower (P < 0.05) than those in the Control, while the levels of LH, P, and E2 in the T2 group were significantly greater (P < 0.05) than those in the T1 group. Zearalenone significantly increased (P < 0.05) the expression of estrogen receptor α in uterus and ovary and estrogen receptor β in vagina, while these indicators were not significant different (P > 0.05) between the T2 group and the Control group. In comparison with the Control group, ZEA significantly increased (P < 0.05) expression of several ATP-binding cassette (ABC) transporters: ABCB1 and ABCb4 in the vagina, ABCA1 and ABCb4 in the uterus, and ABCB1, ABCb4, ABCD3, and ABCG2 in the ovary, while these transporters in the T2 group were significantly decreased (P < 0.05) compared with the T1 group. In conclusion, the present study demonstrates that B. licheniformis CK1 could alleviate the harmful effect of ZEA in Tibetan piglets.

Glucuronides of phytoestrogen flavonoid enhance macrophage function via conversion to aglycones by β-glucuronidase in macrophages

Introduction

Flavonoids are converted to inactive metabolites like glucuronides in the gut, and circulate mainly as glucuronides in blood stream, resulting in low concentrations of active aglycones in plasma. It is therefore unclear how oral flavonoids exert their effects in tissues. We recently reported the plasma pharmacokinetics of some flavonoids and suggested the possibility that the absorbed flavonoids modified macrophage functions leading to enhance bacterial clearance. We aimed to confirm their pharmacological profiles focusing on tissue macrophages.

Methods

Pseudoinfection was induced by intradermal injection of FITC‐conjugated and killed Staphylococcus aureus into the ears of mice treated with or without genistein 7‐O‐glucuronide (GEN7G, 1 mg/kg, i.v.). FACS analysis was performed on single cell suspensions dispersed enzymatically from the skin lesions at 6 h post pseudoinfection to evaluate phagocytic activities of monocytes/macrophages (CD11b⁺Ly6G⁻) and neutrophils (CD11b⁺Ly6G⁺). Phagocytosis of the FITC‐conjugated bacteria by four glucuronides including GEN7G was evaluated in cultures of mouse macrophages.

Results

After GEN7G injection, genistein was identified in the inflamed ears as well as GEN7G, and the phagocytic activity of CD11b⁺Ly6G⁻ cells was increased. GEN7G was converted to genistein by incubation with macrophage‐related β‐glucuronidase. Macrophage culture assays revealed that GEN7G increased phagocytosis, and the action was dampened by a β‐glucuronidase inhibitor. Binding of aglycones to estrogen receptors (ERs), putative receptors of flavonoid aglycones, correlated to biological activities, and glucuronidation reduced the binding to ERs. An ER antagonist suppressed the increase of macrophage function by GEN7G, whereas estradiol enhanced phagocytosis as well.

Conclusions

This study suggests a molecular mechanism by which oral flavonoids are carried as glucuronides and activated to aglycones by β‐glucuronidase in tissue macrophages, and contributes to the pharmacological study of glucuronides.

Uterine responses to feeding soy protein isolate and treatment with 17β-estradiol differ in ovariectomized female rats

There are concerns regarding reproductive toxicity from consumption of soy foods, including an increased risk of endometriosis and endometrial cancer, as a result of phytoestrogen consumption. In this study, female rats were fed AIN-93G diets made with casein (CAS) or soy protein isolate (SPI) from postnatal day (PND) 30, ovariectomized on PND 50 and infused with 5 μg/kg/d 17β-estradiol (E2) or vehicle. E2 increased uterine wet weight (P<0.05). RNAseq analysis revealed that E2 significantly altered expression of 1991 uterine genes (P<0.05). SPI feeding had no effect on uterine weight and altered expression of far fewer genes than E2 at 152 genes (P<0.05). Overlap between E2 and SPI genes was limited to 67 genes. Functional annotation analysis indicated significant differences in uterine biological processes affected by E2 and SPI and little evidence for recruitment of estrogen receptor (ER)α to the promoters of ER-responsive genes after SPI feeding. The major E2 up-regulated uterine pathways were carcinogenesis and extracellular matrix organization, whereas SPI feeding up-regulated uterine peroxisome proliferator activated receptor (PPAR) signaling and fatty acid metabolism. The combination of E2 and SPI resulted in significant regulation of 504 fewer genes relative to E2 alone. The ability of E2 to induce uterine proliferation in response to the carcinogen dimethybenz(a)anthracene (DMBA) as measured by expression of PCNA and Ki67 mRNA was suppressed by feeding SPI (P<0.05). These data suggest that SPI is a selective estrogen receptor modulator (SERM) interacting with a small sub-set of E2-regulated genes and is anti-estrogenic in the presence of endogenous estrogens.

Combinatorial effects of genistein and sex-steroids on the level of cystic fibrosis transmembrane regulator (CFTR), adenylate cyclase (AC) and cAMP in the cervix of ovariectomised rats

The combinatorial effects of genistein and estrogen (E) or estrogen plus progesterone (E+P) on CFTR, AC and cAMP levels in cervix were investigated. Ovariectomised adult female rats received 50 or 100mg/kg/day genistein with E or E followed by E+P [E+(E+P)] for seven consecutive days. Cervixes were harvested and analyzed for CFTR mRNA levels by Real-time PCR. Distribution of AC and CFTR proteins in endocervix were observed by immunohistochemistry. Levels of cAMP were measured by enzyme-immunoassay. Molecular docking predicted interaction between genistein and AC. Our results indicate that levels of CFTR, AC and cAMP in cervix of rats receiving genistein plus E were higher than E-only treatment (p<0.05) while genistein plus [E+(E+P)] were higher than E+(E+P)-only treatment (p<0.05). In conclusions, increased levels of CFTR, AC and cAMP in cervix of E and E+(E+P)-treated rats by genistein could affect the cervical secretory function which could influence the female reproductive processes.

Exogenous estradiol improves shell strength in laying hens at the end of the laying period

Background

Cracked shells, due to age related reduction of shell quality, are a costly problem for the industry. Parallel to reduced shell quality the skeleton becomes brittle resulting in bone fractures. Calcium, a main prerequisite for both eggshell and bone, is regulated by estrogen in a complex manner. The effects of estrogen, given in a low continuous dose, were studied regarding factors involved in age related changes in shell quality and bone strength of laying hens. A pellet containing 0.385 mg estradiol 3-benzoate (21-day-release) or placebo was inserted subcutaneously in 20 birds each of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB) at 70 weeks of age. Eggs were collected before and during the experiment for shell quality measurements. Blood samples for analysis of total calcium were taken three days after the insertion and at sacrifice (72 weeks). Right femur was used for bone strength measurements and tissue samples from duodenum and shell gland were processed for morphology, immunohistochemical localization of estrogen receptors (ERα, ERβ), plasma membrane calcium ATPase (PMCA) and histochemical localization of carbonic anhydrase (CA).

Results

Estrogen treatment increased shell thickness of both hybrids. In addition, shell weight and shell deformation improved in eggs from the brown hybrids. The more pronounced effect on eggs from the brown hybrid may be due to a change in sensitivity to estrogen, especially in surface epithelial cells of the shell gland, shown as an altered ratio between ERα and ERβ. A regulatory effect of estrogen on CA activity, but not PMCA, was seen in both duodenum and shell gland, and a possible connection to shell quality is discussed. Bone strength was unaffected by treatment, but femur was stronger in LSL birds suggesting that the hybrids differ in calcium allocation between shell and bone at the end of the laying period. Plasma calcium concentrations and egg production were unaffected.

Conclusions

A low continuous dose of estrogen improves shell strength but not bone strength in laying hens at the end of the laying period.

Genistein-induced fluid accumulation in ovariectomised rats' uteri is associated with increased cystic fibrosis transmembrane regulator expression

OBJECTIVE

High genistein doses have been reported to induce fluid accumulation in the uteri of ovariectomised rats, although the mechanism underlying this effect remains unknown. Because genistein binds to the oestrogen receptor and the cystic fibrosis transmembrane regulator mediates uterine fluid secretion, we hypothesised that this genistein effect involves both the oestrogen receptor and cystic fibrosis transmembrane regulator.

METHODS

Ovariectomised adult female Sprague-Dawley rats were treated with 25, 50, or 100 mg/kg/day genistein for three consecutive days with and without the ER antagonist ICI 182780. One day after the final drug injection, the animals were humanely sacrificed, and the uteri were removed for histology and cystic fibrosis transmembrane regulator mRNA and protein expression analysis using real-time polymerase chain reaction and Western blotting, respectively. The cystic fibrosis transmembrane regulator protein distribution was analysed visually by immunohistochemistry.

RESULTS

The histological analysis revealed an increase in the circumference of the uterine lumen with increasing doses of genistein, which was suggestive of fluid accumulation. Moreover, genistein stimulated a dose-dependent increase in the expression of cystic fibrosis transmembrane regulator protein and mRNA, and high-intensity cystic fibrosis transmembrane regulator immunostaining was observed at the apical membrane of the luminal epithelium following 50 and 100 mg/kg/day genistein treatment. The genistein-induced increase in uterine luminal circumference and cystic fibrosis transmembrane regulator expression was antagonised by treatment with ICI 182780.

CONCLUSION

Genistein-induced luminal fluid accumulation in ovariectomised rats' uteri involves the oestrogen receptor and up-regulation of cystic fibrosis transmembrane regulator expression, and these findings reveal the mechanism underlying the effect of this compound on changes in fluid volume in the uterus after menopause.