Annona muricata Linn Stem Bark Protects against Uterine Proliferative Disorder Induced by Estradiol Benzoate in Female Rat

Aim: The opening of mitochondrial permeability transition (mPT) pore is an important event in the execution of mitochondrial-mediated apoptosis. Some bioactive compounds elicit their chemotherapeutic effects against tumor/cancer cells via the induction of mitochondrial-mediated apoptosis. Annona muricata, a medicinal plant, is folklorically used in the treatment of tumors and cancers. This study therefore aimed at investigating the effect of methanol stem bark extract of Annona muricata (MEAM) on apoptosis via mPT pore and estradiol benzoate (EB)-induced proliferative disorder using female Wistar rats. Methodology: Mitochondria were isolated using differential centrifugation. The mPT pore opening, cytochrome c release and mitochondrial ATPase activity were determined spectrophotometrically. The levels of estrogen (E2), luteinizing hormone (LH), follicle stimulating hormone (FSH), malondialdehyde (MDA) and activities of superoxide dismutase (SOD), glutathione peroxidase (GSH), were determined using ELISA technique. Histological and histochemical assessments of the uterine sections were carried out using standard methods. Phytochemical constituents of MEAM were determined using Gas Chromatography-Mass Spectroscopy (GC-MS). Results: The in vitro results showed a significant induction of mPT pore opening, release of cytochrome c and enhancement of mitochondrial ATPase (mATPase) activity in a concentration-dependent manner. However, oral administration of MEAM did not induce rat uterine mPT pore opening, neither any significant release of cytochrome c nor enhancement of mATPase activity at the dosages used. Interestingly, MEAM reversed the EB-induced increase in E2, LH and FSH. The MEAM also improved the antioxidant milleu by reducing MDA level and increasing the SOD and GSH-Px activities in the treatment groups. Administration of EB induced endometrial hyperplasia in the model group which was mitigated by MEAM in the treatment group. The GC-MS analysis of MEAM revealed the presence of some important phytochemicals that are pharmacological relevant in cancer treatment. Conclusions: This study suggests that the methanol stem bark extract of Annona muricata contains bioactive compounds that protect against EB-induced uterine proliferative disorder in female Wistar rats.

Development of fixed-time artificial insemination protocols for locally adapted Curraleiro Pé-Duro cows / Desenvolvimento de protocolos de inseminação artificial em tempo fixo em vacas da raça localmente adaptada Curraleiro Pé-Duro

Two experiments were conducted aiming to evaluate the effects of two ovulatory inducers (Exp.1) and equine chorionic gonadotropin (eCG; Exp.2) on follicular and luteal dynamics in a fixed-time AI (FTAI) protocol in locally adapted Curraleiro Pé-Duro cows. In Exp. 1 multiparous cows (n=12) received an intravaginal device containing 1g of progesterone (P4) for 8 days and 2mg of estradiol benzoate (EB) intramuscularly (IM) at device insertion (Day 0). At device removal (Day 8) 0.150mg of Sodium D-Cloprostenol was administered IM and the cows were randomly assigned to receive 1mg of EB (EB8) or 1mg of estradiol cypionate (EC8) IM, or to not receive any ovulatory inducer (Control). All the animals participated in all treatments (crossover). The interval from P4 removal to ovulation was shorter and less variable in the EB8 treatment group (P≤0.05). In Exp. 2 (crossover), multiparous cows (n=12) received the same hormonal treatment as the EB8 group in Exp.1. At device removal (Day 8) cows were randomly assigned to receive 300UI of eCG IM or to not receive eCG (Control). No difference was ascertained on follicular and luteal parameters in Exp. 2 (P>0.05). We concluded that EB can be used as the ovulatory inducer (Exp. 1) in a FTAI protocol in Curraleiro Pé-Duro cows. However, eCG (Exp. 2) was not able to stimulate follicular and luteal development. This result is probably due to the adaptive capacity of Curraleiro Pé-Duro cows that maintained a satisfactory body condition score even in dry and hot environments.(AU)

Foram realizados dois experimentos com o objetivo de avaliar o efeito de dois indutores da ovulação e da gonadotrofina coriônica equina (eCG) na dinâmica folicular e luteal, em um protocolo de inseminação artificial em tempo fixo (IATF) em vacas localmente adaptadas da raça Curraleiro Pé-Duro. No experimento 1, vacas pluríparas receberam um dispositivo intravaginal contendo 1g de progesterona (P4) durante oito dias e 2mg de benzoato de estradiol (BE) intramuscular (IM) no momento da inserção do dispositivo (dia zero). Na retirada do dispositivo (dia oito), as vacas receberam 0,150mg de D-cloprostenol sódico IM e foram separadas aleatoriamente para receber 1mg de BE IM (BE8) ou 1mg de cipionato de estradiol IM (CE8), ou nenhum indutor da ovulação (controle). Todos os animais participaram de todos os tratamentos (crossover). O intervalo entre a retirada da P4 e a ovulação foi menor e menos variável no tratamento BE8 (P≤0,05). O momento da ovulação foi mais precoce e mais concentrado nos animais do grupo BE 8. No experimento 2 (crossover), vacas pluríparas receberam o mesmo tratamento hormonal do grupo BE8 do experimento1. Na retirada do dispositivo (dia 8), as vacas foram separadas aleatoriamente para receberem 300UI de eCG IM, enquanto o controle não. Não houve diferença nos parâmetros foliculares e luteais avaliados no experimento 2 (P>0,05). Em conclusão, o BE pode ser utilizado como indutor da ovulação (experimento 1) em protocolos de IATF em vacas Curraleiras Pé-Duro. Entretanto, o eCG (experimento 2) não foi capaz de estimular o desenvolvimento folicular e luteal. Esse resultado é devido provavelmente à capacidade adaptativa das vacas Curraleiras Pé-Duro em manter uma condição corporal satisfatória mesmo em condições de clima seco e quente.(AU)

Effects of estradiol on the expression of estrogen receptor in lens epithelial cell of castrated female Wistar rat / 中华实验眼科杂志

Background Recently researches indicated that estrogen plays important role in maintaining the normal metabolism of lens. Objective This study was to investigate the changes of estrogen receptor( ER ) α and β expressions in lens upon estrogen level in castrated female rat. Methods Sixty clean adult female Wistar rats were randomized into castrated group,sham operation group,ovariectomy group,ovariectomy with low-dose estradiol eyedropping group,ovariectomy with high-dose estradiol eyedropping group,ovariectomy with low-dose estradiol injecting group and ovariectomy with high-dose estradiol injecting group,and 10 rats for each.The castrated animal models were established by ovariectomy for 5 months.Then 50％,100％ oestradiol benzoate eyedrops were used 4 times per day respectively and 0.2 or 0.4 mg/kg oestradiol benzoate were intramuscularly injected at two-day interval for 6 weeks in corresponding experimental group.Serum estradiol concentration was detected in the rats of various groups at 5 months after ovariectomy and 6 weeks after administration of estradiol benzoate.The animals were sacrificed using the excessive anesthesia method and the lenses were obtained for the assay of ERα and ERβ expressions.The use of the animals complied with the Statement of ARVO. Results No obvious opacification of lenses and the changes of structure and morphology in lens were seen in the rats of various groups under the slit lamp microscope and light microscope during the observing duration after ovariectomy.The significant differences were found in serum estradiol concentrations among the 6 groups ( F=15490.527,P=0.000) or between before and after usage of estradiol benzoate( F=943.236,P =0.001 ).Six weeks after usage of estradiol benzoate,the expressions of ERα and ERβ in the lenses were lower in the castrated group,ovariectomy with high-dose estradiol eyedropping group and ovariectomy with low-dose estradiol injecting group compared with the the sham operative group (P＜0.05),but those in the ovariectomy with low-dose estradiol eyedropping group and ovariectomy with high-dose estradiol injecting group were elevated in comparison with above groups( P＜0.05 ),and expressions of ERα and ERβ in the lenses were similar to the sham operative group ( ERα:28.04±6.80 vs.31.30±7.11 ;ERβ:27.75±7.13 vs.25.38±5.59).Mean A values of ERα and ERβ in the lenses were lower in the castrated group,ovariectomy with high-dose estradiol eyedropping group and ovariectomy with low-dose estradiol injecting group compared with the sham operative group (P＜0.05),but those in the ovariectomy with low-dose estradiol eyedropping group and ovariectomy with high-dose estradiol injecting group were elevated in comparison with above groups ( P＜0.05 ),and mean 4 values of ERα and ERβ in the lenses were similar to the sham operative group (ERα:0.1833 ±0.0087 vs.0.1859 ±0.0067; ERβ:0.1689±0.0059 vs.0.1686±0.0095). Conclusions The expressions of ERα and ERβ in the LECs are associated with the level of serum estradiol.The effects of estrogen on lens were different by different medication way.Low-dose estradiol eyedropping was a more feasible approach to the prevention of cataract.

Effect of medroxy-progesterone acetate on follicular growth and endometrial cycloxygenase-2 (COX-2) expression during the bovine estrous cycle / Efeito do acetato de medroxi-progesterona sobre o crescimento filicular e expressão endometrial de ciclooxigenase-2 (COX-2) durante o ciclo estral de bovinos

The objective of this study was to evaluate the effect of medroxy-progesterone acetate (MAP) with or without estradiol benzoate (EB) on follicular growth during the estrous cycle in cattle. In the first experiment, Hereford cows were synchronized with a synthetic analogue of PGF2 alpha and were treated with two different doses of MAP (250 or 500 mg) with or without EB for 7 days starting on day 8 of the estrous cycle. Follicular growth was inhibited (P<0.05) in all cows except controls and those receiving 250mg MAP without EB. Seventy-five percent of the animals (15/20) showed estrus on days 21 and 22 of the cycle rather than at MAP withdrawal, demonstrating that these treatments did not induce estrus. To determine whether the EB treatment altered endometrial sensitivity to oxytocin and thus the luteolytic cascade, multiparous pre-synchronized cows received 5 mg of EB followed 6 hours later with 50 IU of oxytocin (OT; n=9). Eight hours after EB injection, endometrial fragments were collected from the cows on days 4, 13 and 17 of the estrous cycle and COX-2 gene expression was measured by PCR. EB increased COX-2 mRNA levels only on day 17 of the estrous cycle (P<0.05). In conclusion, MAP alone or associated with EB is able to suppress bovine follicular growth. However, EB in the presence of MAP is not efficient to induce luteolysis in cows when injected on day 8 of the estrous cycle.

Este estudo teve como objetivo avaliar o efeito do acetato de medroxi-progesterona (MAP) com ou sem benzoato de estradiol (BE) sobre o crescimento folicular durante o ciclo estral bovino. No primeiro experimento, vacas da raça Hereford foram sincronizadas com um análogo sintético de PGF2á e tratadas com duas doses diferentes de MAP (250 ou 500mg), com ou sem EB, durante 7 dias, iniciando-se no oitavo dia do ciclo estral. Observou-se uma inibição do crescimento folicular (P<0,05) em todas as vacas, exceto no grupo controle e no grupo que recebeu 250mg de MAP sem BE. Os 75 por cento dos animais não exibiu estro no momento da remoção do MAP, mas sim nos dias 21 e 22 do ciclo, demonstrando que os tratamentos não induziram cio. Para se determinar se o tratamento com BE alterou a sensibilidade endometrial à ocitocina e, assim, a cascata luteolítica, vacas multíparas pré-sincronizadas receberam 5mg de BE, seguidos, após 6 horas, de 50 UI de ocitocina (OT; n=9). Oito horas após a administração de BE, colheram-se fragmentos endometriais das vacas, nos dias 4, 13 e 17 do ciclo estral, mensurando-se a expressão gênica de COX-2 através de PCR. O BE aumentou os níveis de RNAm de COX-2 apenas no dia 17 do ciclo estral (P<0,05). Em conclusão, o MAP isolado ou associado a BE é capaz de suprimir o crescimento folicular bovino. Entretanto, o BE, na presença de MAP é ineficaz na indução da luteólise bovina, quando injetado no oitavo dia do ciclo estral.

Effects of estradiol benzoate on the pathological changes of brain in 2VO-OVX rats / 第三军医大学学报

Objective To study the effects of estradiol benzoate on the morphology and number of neurons in cerebral frontal cortex and hippocampal CA1 area of 2VO OVX rats Methods Eighteen female Wistar rats were randomly divided into 3 groups, that is, sham operation, 2VO OVX (bilateral common carotid artery occlusion and ovariectomy)+ sesame oil, and 2VO OVX+estrogen replacement (named as S, O and E groups respectively) The changes of morphology and number of neurons in frontal cortex and hippocampal CA1 were studied with light and electron microscopy Results The numbers and shape of neurons in frontal cortex and CA1 were well maintained in E group, better than in O group but worse than in S group Significant differences were found in neuron number among 3 groups ( P