Abstract The nucleus accumbens shell (NAcSh) plays a role in appetitive and negative motivation with sex differences in responses. NAcSh and its laterality in metabolic and hormonal responses to chronic stress in female rats is evaluated via transient inactivation of this nucleus during stress induction. Animals in the stress groups received consecutive stress for four days and transient inactivation of NAcSh was performed by administrating lidocaine (0.2%) unilaterally or bilaterally in the nucleus for five minutes before electric foot shock induction. After stress termination, food and water intake, latency to eat, plasma glucose, corticosterone, estradiol and progesterone were measured in all groups. Results showed that stress increased food intake and blood glucose level, but there were no change in the latency to eat and the amount of water intake. The right side, the left side, and both sides of NAcSh may be dominant in latency to eat, food intake, and both water intake and plasma glucose level, respectively. Although chronic stress included no changes for corticosterone and progesterone, it increased estradiol level in plasma. Also, bilateral and right sides of NAcSh may have modulatory effects on stress in corticosterone and progesterone, respectively, without affecting estradiol. It can be concluded that the NAc shell plays a pivotal role in metabolic and hormonal responses to chronic stress in a laterality manner in female rats.
Abstract Crocus sativus L., Iridaceae, has been used worldwide in traditional medicinefor treatment ofsome neurological disorderssuch as depression. Post-traumatic stress disorder is a mental disorder developed in peoplewho experience stressful events. Since stress has been proposed tocause thehypothalamic-pituitary-adrenal axis malfunction in post-traumatic stress disorder patients, this study aimed at investigating the effect of saffron aqueous extract on hypothalamic-pituitary-adrenal axis activity in rats of post-traumatic stress disorder model. Here, Post-traumatic stress disorder animals received an acute electro foot shock; however, 5 min before the stress session, these animals received an intra-cerebral-ventricular (10 µg/rat) infusion of either saffron aqueous extract or saline. Twenty one days later, they were re-exposedto the stress box withoutinducing stress, andthen were examined for their freezing behavior. The impact of stress and saffron aqueous extract on serum corticosterone, corticotrophin releasing hormone gene expression in hypothalamus and glucocorticoid receptor gene expression in pituitary gland werethen evaluated on day 28. Intra-cerebral-ventricular injection of saffron aqueous extract resulted in an increase in serum corticosterone level and reduced symptoms of freezing behavior, and corticotrophin releasing hormone and glucocorticoid receptor gene expression in post-traumatic stress disorder groups.Saffron administration could improve the symptoms of stress-induced post-traumatic stress disorder, possiblythrough the adjustment ofhypothalamic-pituitary-adrenal axis function.
ABSTRACT Stress can inhibit gonadal activity via Hypothalamus-Pituitary-Gonad (HPG) axis activity suppression. In the present study, effects of intermittent feeding (IF) on gonadal function under stress in male and female mice were evaluated. Twenty eight male and twenty eight female mice's were divided into four groups. The control group received adequate food and water without stress. The second group received four days of electric shock without food deprivation. The third group was deprived of food two hours/day for a week, and the fourth group was deprived of food (2 hours/day for seven consecutive days) and then electric foot shock stress was applied to them for four days. Blood samples were collected from all animals for plasma testosterone, estrogen and/or Interlukin-6 (IL-6) evaluation. The animals’ gonads were also removed and fixed for the measure of their weight. Results showed that stress reduces both testosterone and estrogen levels, whereas IF did not change the hormone levels. In addition, stress increases blood IL-6 concentration. The combination of IF and stress, increased the hormone levels in animals. Stress and IF alone had no significant effect on gonadal weight in the male mice, whereas stress decreased gonadal weight in the females. Combination of stress with IF increased gonadal weight in both male and female mice. In conclusion stress showed a negative effect on gonadal function in both animals with more effect on females. Intermittent feeding inhibits the stress effect and even promotes the gonadal function in both sexes. The effect may be due to IL-6 reduction.
Based on previous studies, a variety of bioenvironmental elements including inappropriate nutrition, diseases, infections, stressors, and medications are involved in epigenetic changes. Drug abuse is one of the most important causes of epigenetic changes and a concern in today's world. Studies have shown that morphine use by pregnant mothers causes several disorders in mothers in addition to transferring abnormalities to the next generation (placenta and embryo). Epigenetic factors such as morphine cause changes in gene expression in placenta as the first embryonic defense barrier. Because placenta does all the nutritional exchanges between mother's and embryo's blood, placental health guarantees normal embryonic development. Many studies have been conducted on defects caused by epigenetic factors including medication use. Opioid abuse including morphine abuse has endangered health of many people. Morphine changes gene expression by binding to opioid receptors on placental villi. Based on the studies, major epigenetic changes due to drug use are mediated by DNA methylation and histone changes. Recognizing different epigenetic factors and their effect on placental and embryonic development is among modern studies. The importance of recognizing epigenetic changes caused by drug abuse by pregnant mothers can be the most important way to prevent adulthood diseases in the embryo and in some cases miscarriage. Changes induced by epigenetic factors can be moderated or reversed by controlling the epigenetic factors. This study is a review of changes caused by morphine use by pregnant rats on development of placenta.
Basado en estudios anteriores, una variedad de elementos bioambientales incluyendo la nutrición inadecuada, enfermedades, infecciones, factores de estrés, y los medicamentos están involucrados en los cambios epigenéticos. El abuso de drogas es una de las causas más importantes de los cambios epigenéticos y una preocupación en el mundo actual. Los estudios han demostrado que el uso de la morfina por parte de las madres embarazadas es la causa de varios trastornos en las madres, además de la transferencia de anormalidades a la siguiente generación (la placenta y el embrión). Factores epigenéticos como la morfina causan cambios en la expresión génica en la placenta como la primera barrera de defensa embrionaria. Debido a que la placenta es el medio de todos los intercambios nutricionales entre la madre y la sangre del embrión, la salud de la placenta garantiza el desarrollo embrionario normal. Muchos estudios se han realizado sobre los defectos causados por factores epigenéticos que incluyen el uso de medicamentos. El abuso de opioides, incluyendo la morfina ha puesto en peligro la salud de muchas personas. La morfina produce cambios de expresión génica mediante la unión a los receptores opioides en vellosidades placentarias. Basado en los estudios, los principales cambios epigenéticos debido al consumo de drogas están mediadas por metilación del ADN y los cambios en las histonas. En la actualidad se han publicado estudios referente al conocimiento de diferentes factores epigenéticos y su efecto sobre la placenta y el desarrollo embrionario. La importancia de reconocer los cambios epigenéticos causados por el abuso de drogas por mujeres embarazadas puede ser la forma más importante para prevenir las enfermedades de la edad adulta en el embrión y en algunos casos del aborto espontáneo. Los cambios inducidos por factores epigenéticos pueden ser moderados o revertidos mediante el control de los factores epigenéticos. Este estudio es una revisión de los cambios en el desarrollo de la placenta causados por el uso de morfina en ratas preñadas.
Abstract Lavandula officinalis Chaix, Lamiaceae, extracts can inhibit inflammation and also pain induced by formalin in mice. This study evaluated the effects of L. officinalis hydro-alcoholic extract on pain induced by formalin and also cyclooxygenase (COX) type 1 and 2 activity in mice. To evaluate probable analgesic and anti-inflammatory effects of the extract, flowers were prepared by maceration and extraction in alcohol and their analgesic effects were studied in male mice, using formalin and hot plate tests. The effect of intraperitoneal hydro-alcoholic extracts of L. officinalis (100, 200, 250, 300, 400 and 800 mg/kg), subcutaneous morphine (10 mg/kg), dexamethasone (10 mg/kg; i.p.) and indomethacin (10 mg/kg; i.p.) on formalin induced pain were studied. Our results indicated that administration of the extract (100, 200, 250, 300, 400 and 800 mg/kg; i.p.) has inhibitory effects on inflammation induced by formalin injection into the animals hind paw. Moreover, this inhibitory effect was equal to the effects of morphine, dexamethasone and indomethacin. The extract in100, 200 and 300 mg/kg; significantly reduced heat-induced pain. The extract also reduced COX activity in dose dependent manner, where the inhibitory effect on COX1 activity was 33% and on COX2 activity was 45%. Here for the first time we show that L. officinialis extract can modulate pain and inflammation induced by formalin by inhibition of COX enzymes.