Ethanolic extract of Persea americana Mill. (Lauraceae) seeds induced antiestrogenic effects in young female Wistar rats

OBJECTIVES

The ethanol extract of Persea americana seeds was found to inhibit the development of estrogen-dependent conditions in female Wistar rats, suggesting the ability of its secondary metabolites to interact with estrogen receptors (ERs), either as partial agonists or as antagonists. To test this hypothesis, the abovementioned extract was assessed for its ability to mimic and/or antagonize estradiol effects.

METHODS

Two experiments were conducted in ovariectomized (OVX) rats: (1) animals were treated with estradiol valerate (E2V; 1 mg/kg) or P. americana at doses of 25 and 50 mg/kg; (2) animals were treated with E2V alone (0.75 mg/kg) or in combination with P. americana at the abovementioned doses. Treatments were given orally for 3 days and animals were sacrificed for biochemical and histological analyses of the uterus and vagina.

RESULTS

When administered alone, P. americana did not change the histomorphology of both organs (uterus and vagina). In combination with E2V, P. americana decreased uterine weight [30 % decrease (p<0.001) at 25 mg/kg and 24 % (p<0.01) at 50 mg/kg] and epithelium height (37 % decrease). This was associated with decreased estradiol levels (at least 86 % decrease, p<0.001) in the uterus. Similarly, vagina epithelium height decreased by at least 34 % (p<0.05) when E2V was co-administered with P. americana.

CONCLUSIONS

The seed extract of P. americana contains ER antagonist secondary metabolites accounting for its ability to inhibit the development of estrogen-dependent conditions in female rats.

Allium ampeloprasum var. Porrum (Alliaceae) Improves Metabolic and Reproductive Disorders Associated with Polycystic Ovary Syndrome in Wistar Rats

To provide scientific evidence of the efficacy of Allium ampeloprasum against female infertility, the effects of the aqueous extract of the said plant (AE) were evaluated in rats with letrozole-induced polycystic ovary syndrome (PCOS). AE was administered orally to PCOS rats at doses of 192, 384, and 768 mg/kg. The positive control was co-treated with clomiphene citrate (1 mg/kg) and metformin (200 mg/kg). Normal and negative controls received distilled water. The vaginal contents of rats were examined daily under a microscope before (7 days) and during treatment. Treatments were administered orally for 15 days, and then, 6 rats from each group were sacrificed for biochemical and histological analyses. The remaining rats were mated with males of proven fertility for 5 days. The daily examination of vaginal smears allowed the evaluation of fertility index. After parturition, additional fertility parameters were determined. Results showed that in PCOS rats, AE decreased body weight (p < 0.001), abdominal fat weight (p < 0.001), serum levels of LH (p < 0.001), testosterone (p < 0.001), total cholesterol (p < 0.05), and LDL cholesterol (p < 0.01). HDL cholesterol increased and atherogenic indices decreased (p < 0.001). The number of Graafian follicles and corpora lutea increased, while cystic (p < 0.001) and atretic (p < 0.05) follicles decreased. AE also decreased oxidative stress in the ovaries, restored the estrous cycle, induced uterine epithelial cell hypertrophy, and improved fertility. These effects were attributed to phenols, flavonoids, terpenoids, and anthocyanins present in AE. The overall results justify the traditional use of A. ampeloprasum against female infertility and suggest its potential use as a dietary supplement for PCOS patients.

Alpinumisoflavone Activates Disruption of Calcium Homeostasis, Mitochondria and Autophagosome to Suppress Development of Endometriosis

Alpinumisoflavone is an isoflavonoid extracted from the Cudrania tricuspidate fruit and Genista pichisermolliana. It has various physiological functions, such as anti-inflammation, anti-proliferation, and apoptosis, in malignant tumors. However, the effect of alpinumisoflavone is still not known in chronic diseases and other benign reproductive diseases, such as endometriosis. In this study, we examined the cell death effects of alpinumisoflavone on the endometriosis cell lines, End1/E6E7 and VK2/E6E7. Results indicated that alpinumisoflavone inhibited cell migration and proliferation and led to cell cycle arrest, depolarization of mitochondria membrane potential, apoptosis, and disruption of calcium homeostasis in the endometriosis cell lines. However, the cellular proliferation of normal uterine epithelial cells was not changed by alpinumisoflavone. The alteration in Ca²⁺ levels was estimated in fluo-4 AM-stained End1/E6E7 and VK2/E6E7 cells after alpinumisoflavone treatment with or without calcium inhibitor, 2-aminoethoxydiphenyl borate (2-APB). The results indicated that a combination of alpinumisoflavone and a calcium inhibitor reduced the calcium accumulation in the cytosol of endometriosis cells. Additionally, alpinumisoflavone decreased oxidative phosphorylation (OXPHOS) in the endometriotic cells. Moreover, protein expression analysis revealed that alpinumisoflavone inactivated AKT signaling pathways, whereas it increased MAPK, ER stress, and autophagy regulatory proteins in End1/E6E7 and VK2/E6E7 cell lines. In summary, our results suggested that alpinumisoflavone could be a promising effective management agent or an adjuvant therapy for benign disease endometriosis.

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.

The role of NLRP3 inflammasome in hepatocellular carcinoma

Inflammasomes play an important role in innate immunity. As a signal platform, they deal with the excessive pathogenic products and cellular products related to stress and injury. So far, the best studied and most characteristic inflammasome is the NLR-family pyrin domain-containing protein 3(NLRP3) inflammasome, which is composed of NLRP3, apoptosis associated speck like protein (ASC) and pro-caspase-1. The formation of NLRP3 inflammasome complexes results in the activation of caspase-1, the maturation of interleukin (IL)-1β and IL-18, and pyroptosis. Many studies have demonstrated that NLRP3 inflammasome not only participates in tumorigenesis, but also plays a protective role in some cancers. Hepatocellular carcinoma (HCC) is a major cause of cancer-related mortality. Currently, due to the lack of effective treatment methods for HCC, the therapeutic effect of HCC has not been ideal. Therefore, it is particularly urgent to explore the pathogenesis of HCC and find its effective treatment methods. The increasing evidences indicate that NLRP3 inflammasome plays a vital role in HCC, however, the related mechanisms are not fully understood. Hence, we focused on the recent progress about the role of NLRP3 inflammasome in HCC, and analyzed the relevant mechanisms in detail to provide reference for the future in-depth researches.

Effects of Tartrazine on Some Sexual Maturation Parameters in Immature Female Wistar Rats

Over the past century, the average age for onset of puberty has declined. Several additives present in our food are thought to contribute significantly to this early puberty which is recognized to also affect people's health in later life. On this basis, the impact of 40-days unique oral administration of the food dye tartrazine (7.5, 27, and 47 mg/kg BW doses) was evaluated on some sexual maturation parameters on immature female Wistar rats. Vaginal opening was evaluated during the treatment period. At the end of the treatments, animals were sacrificed (estrus phase) and the relative weight of reproductive organs, pituitary gonadotrophin and sexual steroids level, cholesterol level in ovaries and folliculogenesis were evaluated. Compared to the control group, animals receiving tartrazine (47 mg/kg BW) showed significantly high percentage of early vaginal opening from day 45 of age, and an increase in the number of totals, primaries, secondaries, and antral follicles; a significant increase in serum estrogen, LH and in uterine epithelial thickness. Our findings suggest that tartrazine considerably disturbs the normal courses of puberty. These results could validate at least in part the global observations on increasingly precocious puberty in girls feeding increasingly with industrially processed foods.

The Aqueous Extract of Dacryodes edulis (Burseraceae) Leaves Inhibits Cell Proliferation Induced by Estradiol on the Uterus and Vagina of Ovariectomized Female Wistar Rats

Proliferation is a cellular process strongly linked to the genesis of cancer. Natural substances with antiproliferative activities are currently potential alternatives in the treatment of cancers. Dacryodes edulis, for instance, is a medicinal plant traditionally used in the treatment of cancer. Scientific studies have reported the antioxidant activity of this plant. In addition, the presence of prostate cancer chemopreventive polyphenols was reported in D. edulis extracts. Therefore, this study was aimed to evaluate the effects of the aqueous extract of D. edulis leaves on cell proliferation induced by estradiol in ovariectomized female Wistar rats. In this regard, ovariectomized (OVX) rats were cotreated with estradiol valerate (E₂V) (0.75 mg/kg) and the aqueous extract of D. edulis leaves. Control groups received either the vehicle (sham-operated animals and the OVX control), E₂V (0.75 mg/kg) only, or E₂V (0.75 mg/kg) and tamoxifen (10 mg/kg). Treatments were administered orally for 3 consecutive days, and animals were sacrificed thereafter. Epithelial heights of the uterus and vagina were assessed. Uterine levels of total cholesterol and estradiol were determined as well. Results showed that the aqueous extract of D. edulis leaves reversed the effects of estradiol as it reduced uterine weight (p < 0.05), uterine (p < 0.05), and vaginal (p < 0.001) epithelium heights. This antiproliferative effect of D. edulis was associated with reduced tissue (uterine) levels of estradiol (p < 0.001). These results suggest that the aqueous extract of D. edulis leaves could be a potential alternative treatment for proliferation-related diseases.

Abyssinone V-4' Methyl Ether, a Flavanone Isolated from Erythrina droogmansiana, Exhibits Cytotoxic Effects on Human Breast Cancer Cells by Induction of Apoptosis and Suppression of Invasion

Abyssinone V-4′ methyl ether (AVME) isolated from Erythrina droogmansiana was recently reported to exhibit anti-mammary tumor effect in mice. The present work was therefore aimed at elucidating its cellular and molecular mechanisms. To achieve our goal, the cytotoxicity of AVME against tumoral and non-tumoral cell lines was evaluated by resazurin reduction test; flow cytometry allowed us to evaluate the cell cycle and mechanisms of cell death; the mitochondrial transmembrane potential, reactive oxygen species (ROS) levels, and caspase activities as well as apoptosis-regulatory proteins (Bcl-2 and Bcl-XL) were measured in MDA-MB-231 cells. Further, the antimetastatic potential of AVME was evaluated by invasion assay. AVME exhibited cytotoxic effects in all tested tumor cell lines and induced a significant increase in the percentage of MDA-MB-231 cells at G2/M and S phases of the cell cycle in a concentration-dependent manner. AVME also induced apoptosis in MDA-MB-231 cells, which was accompanied by the activation of caspase-3 and caspase-9 and downregulation of Bcl-2 and Bcl-XL proteins. Moreover, AVME suppressed cancer cell invasion by the inhibition of the metalloproteinase-9 activity. Findings from this study suggest that AVME has anti-breast cancer activities expressed through mitochondrial proapoptotic pathway including impairment of aggressive behaviors of breast cancer cells.

Alpinumisoflavone triggers GSDME-dependent pyroptosis in esophageal squamous cell carcinomas

Esophageal squamous cell carcinoma (ESCC) presents a common human malignancy in the digestive system. We aimed to explore the critical effects of alpinumisoflavone (AIF) on ESCC in vitro and in vivo. The cell counting kit-8 assay was used to determine cell viability. Colony formation assay was employed to examine the effect of AIF on the long-term growth of ESCC cells. Cell apoptosis was determined by flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. Cell morphologies were observed by light microscopy. The enzyme-linked immunosorbent assay was performed to examine the lactate dehydrogenase release from AIF-treated cells. Immunofluorescent labeling was utilized to examine AIF-induced GSDME expression. Western blot was employed to determine the expression levels of the associated proteins. Immunohistochemistry was performed to determine the localization and expression of the associated proteins in mice tumor tissues. AIF inhibited ESCC cell viability and suppressed cell growth in a dose- and time-dependent fashion. Results showed that AIF promoted apoptosis in ESCC cells. Meanwhile, our results also showed that AIF triggered pyroptotic cell death in ESCC, which was mediated by gasdermin E (GSDME) cleavage. In addition, our experiments provided experimental evidence that AIF-induced GSDME cleavage was dependent on caspase-3 activation. Moreover, the inhibition of GSDSE by knockdown was able to switch the form of cell death from pyroptosis to apoptosis. Furthermore, the results from the xenograft animal model also supported our findings in vitro that AIF was able to promote GSDME-mediated pyroptotic cell death in ESCC. AIF inhibited ESCC growth in vitro and in vivo by triggering GSDME-mediated pyroptotic cell death, which is dependent on caspase-3 activation.

Alpinumisoflavone suppresses hepatocellular carcinoma cell growth and metastasis via NLRP3 inflammasome-mediated pyroptosis

AIM

This research aims to explore the effect of alpinumisoflavone (AIF) as an anti-cancer drug for the treatment of patients with hepatocellular carcinoma (HCC).

METHODS

Cell counting kit-8 (CCK-8) and colony formation assay were used to evaluate the viability of the cells and their clonogenic ability. Cellular migration and their invasion capabilities were detected using the wound-healing and transwell assay, respectively. The release of lactate dehydrogenase (LDH) was detected using the LDH kit. The expression levels of genes in the cells and tumor tissues were examined by qRT-PCR, western blotting, and immunohistochemical techniques. The cells transfected with mRFP-GFP-LC3 adenoviruses were stained to determine their autophagy status. MCC950 (NLRP3 inflammasome inhibitor) and NLRP3 shRNA were used to block NLRP3-mediated pyroptosis. Chloroquine and Atg 5 siRNA were used to inhibit the autophagy of the cells.

RESULTS

AIF suppressed cell proliferation, migration, and invasion capacity of SMMC 7721 and Huh7 cells. The incorporation of AIF induced the formation of NLRP3 inflammasome assembly, pyroptosis, and autophagy of the cells. However, the anti-proliferative and anti-metastatic effects of AIF on the HCC cells were attenuated by NLRP3 inhibitor and knockdown. Furthermore, Atg 5 knockdown inhibited autophagy and enhanced the rate of AIF-induced pyroptosis of the cells. AIF also suppressed tumor growth and increased the levels of pyroptosis-related genes in tumor tissues, which were consistent with in vitro observations.

CONCLUSION

AIF inhibited HCC cell growth and metastasis by inducing NLRP3 inflammasome-mediated pyroptosis. Furthermore, AIF-induced autophagy augmented pyroptosis in HCC.

Alpinumisoflavone suppresses human Glioblastoma cell growth and induces cell cycle arrest through activating peroxisome proliferator-activated receptor-γ

As a common subtype of malignant gliomas, glioblastoma multiforme (GBM) is associated with poor prognosis. This study is aimed to examine the anticancer activities of alpinumisoflavone (AIF) and its underlying mechanisms. Our results demonstrated that AIF inhibited the proliferation of GBM cells (U373 and T98G) in a time and dose-dependent manner. In addition, flow cytometry analysis not only confirmed AIF arrested cell cycle at the G0/G1 phase but also the induced apoptosis of U373 and T98G cells. Western blotting also confirmed that AIF altered the expression levels of cell cycle-related proteins. Further mechanism studies revealed that AIF inhibited cell proliferation, induced G0/G1 phase arrest and induced apoptosis of U373 and T98G cells through activating PPARγ, as evidenced by the fact that GW9662 (PPARγ inhibitor) could effectively reverse the effects of AIF on U373 and T98G cells. Furthermore, the in vivo study also revealed that AIF suppressed tumor growth and caused cell cycle arrest. Collectively, these results highlighted the potential use of AIF in the treatment of GBM.

A Pharmacological Overview of Alpinumisoflavone, a Natural Prenylated Isoflavonoid

Over the last decade, several studies demonstrated that prenylation of flavonoids enhances various biological activities as compared to the respective nonprenylated compounds. In line with this, the natural prenylated isoflavonoid alpinumisoflavone (AIF) has been explored for a number of biological and pharmacological effects (therapeutic potential). In this review, we summarize the current information on health-promoting properties of AIF. Reported data evidenced that AIF has a multitherapeutic potential with antiosteoporotic, antioxidant and anti-inflammatory, antimicrobial, anticancer, estrogenic and antiestrogenic, antidiabetic, and neuroprotective properties. However, research on these aspects of AIF is not sufficient and needs to be reevaluated using more appropriate methods and methodology. Further series of studies are needed to confirm these pharmacological effects, and this review should lay the basis for the design of respective investigations. Overall, despite the drawbacks of studies recorded, AIF exhibits a potential as drug candidate.

Physicochemical, Pharmacokinetic, and Toxicity Evaluation of Methoxy Poly(ethylene glycol)-b-Poly(d,l-Lactide) Polymeric Micelles Encapsulating Alpinumisoflavone Extracted from Unripe Cudrania tricuspidata Fruit

Alpinumisoflavone, a major compound in unripe Cudrania tricuspidata fruit is reported to exhibit numerous beneficial pharmacological activities, such as osteoprotective, antibacterial, estrogenic, anti-metastatic, atheroprotective, antioxidant, and anticancer effects. Despite its medicinal value, alpinumisoflavone is poorly soluble in water, which makes it difficult to formulate and administer intravenously (i.v.). To overcome these limitations, we used methoxy poly(ethylene glycol)-b-poly(d,l-lactide) (mPEG-b-PLA) polymeric micelles to solubilize alpinumisoflavone and increase its bioavailability, and evaluated their toxicity in vivo. Alpinumisoflavone-loaded polymeric micelles were prepared using thin-film hydration method, and their physicochemical properties were characterized for drug release, particle size, drug-loading (DL, %), and encapsulation efficiency (EE, %). The in vitro drug release profile was determined and the release rate of alpinumisoflavone from mPEG-b-PLA micelles was slower than that from drug solution, and sustained. Pharmacokinetic studies showed decreased total clearance and volume of distribution of alpinumisoflavone, whereas area under the curve (AUC) and bioavailability were significantly increased by incorporation in mPEG-b-PLA micelles. In vivo toxicity assay revealed that alpinumisoflavone-loaded mPEG-b-PLA micelles had no severe toxicity. In conclusion, we prepared an intravenous (i.v.) injectable alpinumisoflavone formulation, which was solubilized using mPEG-b-PLA micelles, and determined their physicochemical properties, pharmacokinetics, and toxicity profiles.

Alpinumisoflavone causes DNA damage in Colorectal Cancer Cells via blocking DNA repair mediated by RAD51

AIMS

Colorectal Cancer (CRC) accounts for 6.1% incidence and 9.2% mortality worldwide. The current study aimed to investigate the effect of alpinumisoflavone (AIF) on CRC and its possible molecular mechanism.

METHODS

HCT-116 and SW480 cells were chosen as cell model to study the anti-cancer activity of AIF in vitro experiments. Cells proliferative capacity and clonogenicity were examined by CCK-8 assay and colony formation assay, while cell apoptosis was detected by Hoechst 33258 staining and Flow cytometer. The protein expression levels of related gene were examined by western blotting. Transcriptome analyses were conducted to identify the differentially expressed genes in CRC cells, following AIF treatment. DNA damage was examined by γH2AX foci assay. The anti-cancer effect of AIF in vivo was validated in CRC xenograft model.

KEY FINDINGS

We found that AIF inhibited CRC cell proliferation and promoted apoptosis in a dose-dependent manner, as well as increased the number of γ-H2AX foci. In addition, microarray analysis showed that the DNA-double strand break (DSB) repair gene RAD51 was aberrantly overexpressed in CRC tissues, and was positively correlated with lymph node metastasis, TNM stage and poor outcomes. Both in vitro and in vivo experiments confirm that AIF treatment significantly decreased RAD51 levels. Knockdown RAD51 could enhance the anti-cancer activity of AIF against CRC, while abrogated by RAD51 overexpression.

SIGNIFICANCE

These findings suggest that AIF can be regarded as a potential anti-cancer drug and provide new insights into CRC treatment.

Abyssinone V-4' Methyl Ether Isolated from Erythrina droogmansiana (Leguminosae) Inhibits Cell Growth and Mammary Glands Hyperplasia Induced in Swiss Mice by the 7,12-Dimethylbenz(a)anthracene

There is a long standing interest in the identification of medicinal plants and derived natural products for developing cancer therapeutics. The present study was designed to evaluate the in vitro and in vivo antiproliferative effects of Abyssinone V-4' methyl ether (AVME) on breast tissue of mice. The cytotoxicity of AVME was evaluated using MTT assay in four cancer cell lines (DU145, PC3, HepG2, and MCF-7). Further, a protective effect of AVME was evaluated on 7,12-dimethylbenz(a)anthracene- (DMBA-) induced breast tumor in Swiss mice. Incidence, burden, volume, and histological analysis of mammary tumors were measured. As a result, AVME inhibits DU145, PC3, HepG2, and MCF-7 cells growth. In vivo, no tumor was detected in mice from the normal group as compared to those of DMBA group. Moreover, AVME inhibits the DMBA-induced mammary glands hyperplasia in mice at the dose of 10 mg/kg, evidenced by a decrease of tumor incidence, tumor weight, and volume as well as a protective effect against the lobular alveolar hyperplasia. Taken all together, these results suggest that Abyssinone V-4' methyl ether is endowed with antitumor properties and could be a source of traditional medicine which deserves to be more elucidated and explored in the foreseeable future.

Alpinumisoflavone protects against glucocorticoid-induced osteoporosis through suppressing the apoptosis of osteoblastic and osteocytic cells

The long-term use of glucocorticoids is found to cause osteoporosis. This study is designed to evaluate the protective effect of alpinumisoflavone (AIF), a naturally occurring flavonoid compound, on dexamethasone(Dex)-induced osteoporosis. We use a rat model to investigate the apoptosis of osteoblastic and osteocytic cells. The results indicate that AIF effectively protects against dexamethasone-induced osteoporosis. Moreover, AIF effectively reversed dexamethasone-induced apoptosis in osteoblastic and osteocytic cells through inhibiting ROS overproduction and regulating the Nrf2 pathway. In conclusion, the AIF activated Nrf2 signaling pathway was observed to suppress Dex-induced ROS production in osteoblastic and osteocytic cells, which may explain its anti-osteoporotic effects against dexamethasone-induced osteoporosis.

Alpinumisoflavone rescues glucocorticoid-induced apoptosis of osteocytes via suppressing Nox2-dependent ROS generation

BACKGROUND

Long term use of glucocorticoids is one of the most common causes of secondary osteoporosis. Osteocyte, the most abundant cell type in bone, coordinates the function of osteoblast and osteoclast. This study evaluates the protective effect of alpinumisoflavone (AIF), a naturally occurring flavonoid compound, on dexamethasone (Dex)-induced apoptosis of osteocytes.

METHODS

MLO-Y4 cell was used as a cell model. The effect of AIF on the cell viability was assessed by MTT assay. Apoptosis of MYL-Y4 cells was determined by DNA fragment detection ELISA kit and flow cytometry. Intracellular ROS level was determined by DCFH-DA staining. mRNA and protein expression of target genes were determined by qRT-PCR and western blot, respectively.

RESULTS

AIF effectively protected MLO-Y4 cells against Dex-induced apoptosis, which was associated with attenuation of Dex-induced ROS generation in MLO-Y4 cells. Furthermore, our data indicated that the expression of NAD(P)H oxidase 2 (Nox2) was suppressed by AIF, which in turn mediated the attenuating effect on Dex-induced ROS generation and apoptosis in MLO-Y4 cells. Moreover, our results showed that AIF modulated the expression of Nox2 by activating AMPK signaling.

CONCLUSION

AIF activated AMPK-dependent Nox2 signaling pathway to suppress Dex-induced ROS production in cultured osteocytes, which might explain its anti-apoptotic effect. These results indicate that activation of AMPK pathway by AIF could have beneficial effects on bone damage induced by excessive oxidative stress and osteocyte apoptosis.

Alpinumisoflavone radiosensitizes esophageal squamous cell carcinoma through inducing apoptosis and cell cycle arrest

Radiotherapy remains a mainstream treatment for patients with unresectable and locally advanced esophageal squamous cell carcinoma (ESCC). However, intrinsic radioresistance of ESCC tumors has largely compromised the efficacy of radiotherapy. The following study investigates the potential radiosensitizing effect of alpinumisoflavone (AIF) and explores its underlying mechanisms in ESCC. Briefly, our results showed that AIF could significantly increase radiosensitivity of ESCC cells both in vitro and in vivo, by increasing the effect of AIF on irradiation-induced DNA damage, apoptosis and cell cycle arrest. Mechanically, AIF aggravated irradiation-induced ROS generation in ESCC cells, which occurred via suppressing the expression of nuclear transcription factor Nrf2 and Nrf2-driven antioxidant molecule NQO-1 and HO-1. Collectively, we concluded that AIF functions as a potent radiosensitizer in human ESCC.

Emmenagogue properties of Milicia excelsa (Welw.) C.C. Berg (Moraceae) based, at least in part, on its ability to correlate the activity of the hypothalamic-pituitary axis to that of the ovaries

ETHNOPHARMACOLOGICAL RELEVANCE

Milicia excelsa (Welw.) C.C. Berg (Moraceae) is a medicinal plant recommended over tropical Africa as a cure for several ailments including amenorrhea. This is the hallmark of an ovarian lesion or a dysfunction of the hypothalamic-pituitary-ovarian axis which may lead to infertility, osteoporosis or endometrial cancer. However, regardless these traditional claims, no scientific report dealing with emmenagogue properties has been reported yet.

AIM OF THE STUDY

To bring scientific evidence to the curative action of the plant, we proposed evaluating the effects of a root aqueous extract of Milicia excelsa on female Wistar rat sexual maturation.

MATERIAL AND METHODS

The study was performed in immature (45 days old) female Wistar rats orally treated with the root aqueous extract of Milicia excelsa at doses of 14, 77 and 140mg/kg BW/day for 7 and 15 consecutive days. Genistein (10mg/kg BW) served as the reference substance. Negative control animals, treated with the vehicle, were followed up for 7, 15, 30 and 45 days and rats were aged 52, 60, 75 and 90 days at these respective days. This allowed setting the nubile age of experimental animals and to determine the impact of treatments with genistein or the aqueous extract of Milicia excelsa on the age of rat sexual maturation. Since female rats do not have menstruation and that the normal menstrual cycle occurs because of changing levels of hormones made and secreted by the ovaries in response to hormonal signals from the pituitary gland, the effects of treatments were evaluated on the pituitary production of gonadotropins, the ovarian production of estradiol and progesterone, and uterine and vaginal growths.

RESULTS

The sexual maturation of untreated rats was set at 90 days old. This sexual maturation was indicated by the simultaneous elevation of gonadotropins (FSH and LH (p<0.01)) and ovarian hormones (estradiol (p<0.001) and progesterone (p<0.05)) in animals aged 90 days. Uterine and vaginal growths (p < 0.001) observed in these animals appear as the result of elevated level of estradiol. The root aqueous extract of Milicia excelsa displayed genistein-like effects and increased FSH and estradiol serum levels following both treatment periods (7 and 15 days). Estradiol serum concentration significantly increased following a 7-day treatment at the dose of 14mg/kg BW (p<0.001). This resulted in an increase in the uterine wet weight, uterine and vaginal epithelial heights (p<0.05). These results suggest that the root aqueous extract of Milicia excelsa reduced rats' sexual maturation from 90 to 52 days. Moreover, animals' body weight was not affected following treatment with Milicia excelsa.

CONCLUSION

The root aqueous extract of Milicia excelsa may solve the problem of amenorrhea by synchronizing the activity of the hypothalamic-pituitary axis to the ovarian production of estradiol and progesterone. The unaltered body weight following treatments justifies at least in part, the traditional use of Milicia excelsa for primary and secondary amenorrhea.

Alpinumisoflavone inhibits osteoclast differentiation and exerts anti-osteoporotic effect in ovariectomized mice

Alpinumisoflavone (AIF), a naturally occurring flavonoid compound exacted from Derris eriocarpa, has been found to have a number of pharmacological activities. However, its role in bone disorder has not been investigated. The aim of this study is to evaluate the osteoprotective effect of AIF on ovariectomy-induced bone loss in mice model and related underlying mechanisms. Our study provides experimental evidence that AIF could regulate the remodeling process of bone and exert osteoprotective effect against ovariectomy-induced bone loss. Moreover, our results show that AIF suppresses osteoclast differentiation by attenuating RANKL-induced activation of p38, ERK and JNK pathways and consequently represses the expression of c-Fos and NFATc1.

Estrogenic activity of isoflavonoids from the stem bark of the tropical tree Amphimas pterocarpoides, a source of traditional medicines

Various preparations of the African tree Amphimas pterocarpoides Harms are traditionally used to treat endocrine- related adverse health conditions. In the ovariectomized rat, the enriched in phenolics fraction of the methanol extract of stem bark of A. pterocarpoides acted as vaginotrophic agent of considerably weaker uterotrophic activity compared to estradiol. Evaluation of the fraction and 11 isoflavonoids isolated therefrom using Ishikawa cells and estrogen receptor (ER) isotype-specific reporter cells suggested that the estrogenic activity of the fraction could be attributed primarily to daidzein and dihydroglycitein and secondarily to glycitein. The potency-based selectivity of daidzein, dihydroglycitein and glycitein for gene expression through ERβ versus ERα, expressed relative to estradiol, was 37, 27 and 20, respectively. However, the rank order of relative-to-estradiol potencies of induction of alkaline phosphatase in Ishikawa cells, a reliable marker of estrogenic activity, was daidzein>dihydroglycitein>>glycitein. The considerably higher estrogenic activity of dihydroglycitein compared to glycitein could be attributed to the partial agonist/antagonist activity of dihydroglycitein through ERβ. Calculation of theoretical free energies of binding predicted the partial agonism/antagonism of dihydroglycitein through ERβ. The fraction and the isolated isoflavonoids promoted lactogenic differentiation of HC11 mammary epithelial cells at least as effectively as premenopausal levels of estradiol. This data suggests that the estrogenic activity of the fraction likely depends on the metabolism of glycitein to dihydroglycitein; that the fraction could exert vaginotrophic activity likely without challenging endocrine cancer risk more than estrogen-alone supplementation; and that the fraction's safety for the reproductive track warrants a more detailed evaluation.

Alpinumisoflavone and abyssinone V 4'-methylether derived from Erythrina lysistemon (Fabaceae) promote HDL-cholesterol synthesis and prevent cholesterol gallstone formation in ovariectomized rats

OBJECTIVES

Erythrina lysistemon was found to improve lipid profile in ovariectomized rats. Alpinumisoflavone (AIF) and abyssinone V 4'-methylether (AME) derived from this plant induced analogous effects on lipid profile and decreased atherogenic risks. To highlight the molecular mechanism of action of these natural products, we evaluated their effects on the expression of some estrogen-sensitive genes associated with cholesterol synthesis (Esr1 and Apoa1) and cholesterol clearance (Ldlr, Scarb1 and Cyp7a1).

METHODS

Ovariectomized rats were subcutaneously treated for three consecutive days with either compound at the daily dose of 0.1, 1 and 10 mg/kg body weight (BW). Animals were sacrificed thereafter and their liver was collected. The mRNA of genes of interest was analysed by quantitative real-time polymerase chain reaction.

KEY FINDINGS

Both compounds downregulated the mRNA expression of Esr1, a gene associated with cholesterogenesis and cholesterol gallstone formation. AME leaned the Apoa1/Scarb1 balance in favour of Apoa1, an effect promoting high-density lipoprotein (HDL)-cholesterol formation. It also upregulated the mRNA expression of Ldlr at 1 mg/kg/BW per day (25%) and 10 mg/kg/BW per day (133.17%), an effect favouring the clearance of low-density lipoprotein (LDL)-cholesterol. Both compounds may also promote the conversion of cholesterol into bile acids as they upregulated Cyp7a1 mRNA expression.

CONCLUSION

AIF and AME atheroprotective effects may result from their ability to upregulate mechanisms promoting HDL-cholesterol and bile acid formation.

Erythrina lysistemon-derived flavonoids account only in part for the plant's specific effects on rat uterus and vagina

BACKGROUND

The stem bark ethyl acetate extract of Erythrina lysistemon was found to induce vaginal proliferation in ovariectomized rats orally treated. Alpinumisoflavone (AIF) and abyssinone V-4'-methyl-ether (AME), isolated as its major constituents, were reported to separately provoke uterine growth and/or vaginal proliferation. The present study aimed at evaluating the effects of the mixture of AIF and AME (51 mg/kg [AIF]+153 mg/kg [AME]) following their relative abundance in the extract, in order to compare these effects to those of E. lysistemon.

METHODS

The study was performed in ovariectomized rats treated intraperitoneally for 3 days. Estradiol valerate (E2 V) and AME were used for positive controls. Morphological and histological changes of animals' uterus and vagina were used as the hallmark of estrogenicity.

RESULTS

E. lysistemon extract induced estrogen-like effects only on the uterus and significantly increased uterine wet weight (p<0.01) and uterine epithelial height (p<0.01). These results suggest a tissue-selective action of E. lysistemon extract depending on the route of administration. The mixture of AIF and AME induced E. lysistemon-like effects only at a dose of 1 mg/kg BW/d (0.25 mg/kg+0.75 mg/kg), although these effects were lower in magnitude (p<0.05) compared to those induced by E. lysistemon extract.

CONCLUSIONS

Effects induced by the mixture of AIF and AME are analogous to those of E. lysistemon, but the low magnitude of these effects suggests that there are minor metabolites that interact with AIF and AME to provoke the specific effects of E. lysistemon.

Preventive effects of the methanol soluble fraction of Millettia macrophylla Benth (Fabaceae) on an osteoporosis-like model of ovariectomized Wistar rats

BACKGROUND

Millettia macrophylla Benth is a Cameroonian medicinal plant traditionally used to alleviate menopause-related problems. The methanol soluble fraction of this plant was shown to exhibit estrogenic effects in vitro in Human Embryonic kidney cells, and in vivo on ovariectomized rat following the classical uterotrophic assay. Since estrogens have been involved in bone remodeling process, the present study then aimed at evaluating bone loss preventive effects of the methanol soluble fraction of Millettia macrophylla (MM-met) in ovariectomized rat model.

METHODS

Twenty-five healthy Wistar female rats (3-month-old) were randomly assigned to a sham-operated group and to four treated ovariectomized (OVX) groups. Treatments lasted 8 weeks and animals were sacrificed. The uterus, the femoral and the tibia bones of each animal were collected, weighed and fixed in 10% formalin for histological analysis.

RESULTS

Results showed that ovariectomy decreased uterine wet weight (p<0.01), induced body weight gain (p<0.01), decreased both femoral and tibia bone density and mineral content and increased alkaline phosphatase activity (p<0.05). E2V and MM-met treatments in general prevented bone mass loss and/or bone density loss. At all tested doses, MM-met induced a significant decrease of alkaline phosphatase activity (p<0.05). As observed with E2V, MM-met also induced a significant protective effect on bone, and this was indicated by an abundance of bone marrow in an almost intact trabecular network.

CONCLUSIONS

The overall results show that the methanol soluble fraction of Millettia macrophylla may prevent ovariectomy-induced bone mass loss and deterioration of the trabecular microarchitecture.

The phytoestrogenic compound cajanol from Pigeonpea roots is associated with the activation of estrogen receptor α-dependent signaling pathway in human prostate cancer cells

In the present study, the main natural estrogen-agonist/antagonist from Pigeonpea roots was studied by the estrogen receptor α-dependent signaling pathway in human prostate cancer cell. First, the natural products with estrogenic activity in Pigeonpea roots were screened by pER8-GFP transgenic Arabidopsis, and cajanol (5-hydroxy-3-(4-hydroxy-2-methoxyphenyl)-7-methoxychroman-4-one) was confirmed as the active compound. Further study showed that cajanol significantly arrested the cell cycle in the G1 and G2/M phase and induced nuclei condensation, fragmentation and the formation of apoptotic bodies. Western blotting showed that cajanol modulated the ERα-dependent PI3K pathway and induced the activation of GSK3 and CyclinD1 closely following the profile of PI3K activity. Based on above results, we proposed a mechanism through which cajanol could inhibit survival and proliferation of estrogen-responsive cells (PC-3 cells) by interfering with an ERα-associated PI3K pathway, following a process that could be dependent of the nuclear functions of the ERα. Above all, we conclude that cajanol represents a valuable natural phytoestrogen source and may potentially be applicable in health food industry.