Virgin Female Wistar Rats Research Articles

The hyperplasia of the mammary gland effect of the Mongolian Remedy RuXian-I in rats reduced by estrogen and progesterone via inhibition of MAPK and NF-κB pathways

Background: The aim of the present study was to evaluate whether the HMG (Hyperplasia of the Mammary Gland) effect of RuXian-I in estrogen- and progestogen- induced HMG rats is mediated through the activation of MAPK (Mitogen activated protein kinase) and NF-κB signaling pathways. Materials and methods: Fifty virgin female Wistar rats were randomly divided into in control and HMG, RuXian-I (0.75 g·kg−1, 1.5 g·kg−1, 3 g·kg−1, respectively) groups, 10 in each. Injections of estrogen and progestogen were given to establish rat models of HMG and RuXian-I at the same time. Changes in nipple heights were measured; pathologic changes of HMG in rats were also observed under a light microscope; the phosphorylation levels of MAPK and NF κB and the expression levels of TNF-α and IL-1β were measured. Results: Compared with the control group, the nipple diameters and height were increased significantly, the numbers of MG lobules were increased, there were changes in breast histopathology, the levels of TNF-α and IL-1β increased significantly, and MAPK and NF-κB were activated in HMG rats. Compared with the HMG model group, the increased nipple height was decreased, the numbers of MG lobules were reduced, the degree of HMG in rats was alleviated obviously, and the phosphorylation level of MAPK and NF-κB and cytokines TNF- α and IL-1β levels in serum were decreased by RuXian-I treatment. Conclusion: Those results suggest RuXian-I has protective and therapeutic effects on HMG rats induced by estrogen and progestogen and is likely to activate MAPK and NF-κB signaling pathways.

GC–MS analysis of Moringa oleifera leaf extract and effects of administration on histology of reproductive organs and liver of female rats exposed to chronic unpredictable stress

Exposure to several stressors and other lifestyle factors converge to affect the chemistry, structure, and function of body tissues over time. Chronic unpredictable stress (CUS) protocol has been widely used to study the impact of stress exposure in several animal models. Moringa oleifera leaf extract (MOLE) is known to have hepatoprotective and antioxidant properties. The study aimed to determine the effect of the administration of MOLE during conditions of chronic stress on the histology of reproductive organs, heart and liver. Twenty mature inbred healthy virgin female Wistar rats were randomly placed into four groups of five rats per group as follows: Group One (water and normal rat chow ad libitum), Group Two (CUS protocol only), Group Three (CUS protocol + 200 mg/kg MOLE), Group Four (CUS protocol + 300 mg/kg of MOLE). CUS protocol was applied unpredictably for two weeks. The chromatogram of the GC–MS analysis indicated the presence of 41 compounds. Photomicrograph examination of the uterus, ovaries, and liver showed severe alterations in the histology of the tissues. Consumption of MOLE during chronic stress has shown deleterious effects and is not advised for consumption during stress conditions.

A new vision of photothermal therapy assisted with gold nanorods for the treatment of mammary cancers in adult female rats.

Over the past decade, the therapeutic landscape has markedly changed for patients with breast cancers (BCs), yet few studies have evaluated the power of the photothermal therapy (PTT) technique. The present study aimed to assess the potency of 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary cancer treatment with this technique. In total, forty-two adult virgin female Wistar rats were categorized into seven groups, negative control, polyvinylpyrrolidone-capped gold nanorods (PVP-AuNRs) positive control (400 μL per rat ∼ 78 ppm), NIR laser irradiation 808 nm positive control with an intensity of (808 nm NIR CW diode laser, 200 mW cm-2 for 5 min), DMBA-treatment, DMBA-induced mammary cancer group treated with polyvinylpyrrolidone-capped gold nanorods, DMBA-induced mammary cancer group treated with NIR laser irradiation, and DMBA-induced mammary cancer group treated with polyvinylpyrrolidone-capped gold nanorods and NIR laser irradiation. Treatment with polyvinylpyrrolidone-capped gold nanorods and/or NIR laser irradiation was performed after three weeks of DMBA-induced mammary cancer. The mammary tumor lesions in the rat model induced with DMBA are highly invasive. Synthesis and characterization of gold nanorods (AuNRs) with an aspect ratio ranging from 2.8 to 3 were employed to validate the nanostructure and polyvinylpyrrolidone capping and their stability in absorbing near-infrared light. As a result, the therapy strategy, DMBA + PVP-AuNRs + NIR, effectively treated the tumor and halted its growth. The mammary glands were dissected and subjected to biochemical analysis for serum and tissue. Our treatment technique improved the histological aspects of mammary cancer in various forms of mammary cancer detected. Immuno-histochemical localization and TEM images supported these results reflecting the efficacy of this technique. Finally, our findings uncover for the first time the revolutionary effect of the PTT strategy using PVP-capped AuNRs in selectively destroying mammary cancer cells in rats.

Involvement of Autophagy and Oxidative Stress-Mediated DNA Hypomethylation in Transgenerational Nephrotoxicity Induced in Rats by the Mycotoxin Fumonisin B1.

Fumonisin B1 (FB1), a mycotoxin produced by Fusarium verticillioides, is one of the most common pollutants in natural foods and agricultural crops. It can cause chronic and severe health issues in humans and animals. The aim of this study was to evaluate the transgenerational effects of FB1 exposure on the structure and function of the kidneys in offspring. Virgin female Wistar rats were randomly divided into three groups: group one (control) received sterile water, and groups two and three were intragastrically administered low (20 mg/kg) and high (50 mg/kg) doses of FB1, respectively, from day 6 of pregnancy until delivery. Our results showed that exposure to either dose of FB1 caused histopathological changes, such as atrophy, hypercellularity, hemorrhage, calcification, and a decrease in the glomerular diameter, in both the first and second generations. The levels of the antioxidant markers glutathione, glutathione S-transferase, and catalase significantly decreased, while malondialdehyde levels increased. Moreover, autophagy was induced, as immunofluorescence analysis revealed that LC-3 protein expression was significantly increased in both generations after exposure to either dose of FB1. However, a significant decrease in methyltransferase (DNMT3) protein expression was observed in the first generation in both treatment groups (20 mg/kg and 50 mg/kg), indicating a decrease in DNA methylation as a result of early-life exposure to FB1. Interestingly, global hypomethylation was also observed in the second generation in both treatment groups despite the fact that the mothers of these rats were not exposed to FB1. Thus, early-life exposure to FB1 induced nephrotoxicity in offspring of the first and second generations. The mechanisms of action underlying this transgenerational effect may include oxidative stress, autophagy, and DNA hypomethylation.

Saccharomyces boulardii, a novel yeast probiotic ameliorates metabolic syndrome associated with PCOS: A preliminary study

age accompanied by metabolic alteration. Gut microbiota has been found to play a critical role in the pathophysiology and furtherprogression of PCOS. The wide range of side effects of existing medical management have made it necessary to continuously look foran efficient and safe alternative. Saccharomyces boulardii, the only eukaryotic probiotic with its unique properties is becoming verypopular as the only yeast probiotic. Hypothesis: This preliminary study evaluated the efficacy of S. boulardii on a PCOS-IR (PCOS withinsulin resistance) rat model. Materials and methods: PCOS was induced in all virgin female Wistar rats with 1 mg/kg/day of letrozoleand high fat (40%) diet except for the control group for 21 days. The rats were then co-administered with lyophilized S. boulardii of1.8×107 CFU /kg/Day. Results: S. boulardii prevented the further progression of PCOS by restoring the ovarian morphology and metabolicparameters. Conclusion: However, this mechanism can be attributed by the possible correction of dysbiosis and metabolic alterationin PCOS by S. boulardii.

Prenatal immobility stress: Relationship with oxidative stress, inflammation, apoptosis, and intrauterine growth restriction in rats.

Prenatal stress is a significant risk factor affecting pregnant women and fetal health. In the present study, we aimed to investigate the effect of immobility stress at different periods of pregnancy on oxidative stress, inflammation, placental apoptosis and intrauterine growth retardation in rats. Fifty adult virgin female Wistar albino rats were used. Pregnant rats were exposed to 6 h/day immobilization stress in a wire cage at different stages of pregnancy. Groups I and II (Day 1-10 stress group) were sacrificed on the 10th day of pregnancy, and Group III, Group IV (10-19th-day stress group), and Group V (1-19th-day stress group) were sacrificed on the 19th day of pregnancy. Inflammatory cytokines, including interleukin-6 (IL-6) and interleukin-10 (IL-10), serum corticotropin-releasing hormone (CRH), and corticosterone levels were measured by enzyme-linked immunosorbent assay. Malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) levels in the placenta were spectrophotometrically measured. Histopathological analyses of the placenta were evaluated by hematoxylin and eosin staining. Tumor necrosis factor-alpha (TNF-α) and caspase-3 immunoreactivity in placenta tissues were determined by the indirect immunohistochemical method. Placental apoptosis was determined by the TUNEL staining method. We found that the immobility stress during pregnancy significantly increased serum corticosterone levels. Our results showed that the immobility stress diminished the number and weight of fetuses in rats compared to the non-stress group. The immobility stress caused significant histopathological changes in the connection zone and labyrinth zone and increased placental TNF-α and caspase-3 immunoreactivity and placental apoptosis. In addition, immobility stress significantly increased the levels of pro-inflammatory IL-6 and MDA and caused a significant decrease in the levels of antioxidant enzymes such as SOD, CAT, and anti-inflammatory IL-10. Our data suggest that immobility stress causes intrauterine growth retardation by activating the hypothalamic-pituitary-adrenal axis and deteriorating placental histomorphology and deregulating inflammatory and oxidative processes.

Liraglutide limits the immunogenic cell death-mediated ROS propagation and PI3K/AKT inactivation after doxorubicin-induced gonadotoxicity in rats: Involvement of the canonical Hedgehog trajectory.

Chemotherapy-accompanied reproductive dysfunction has lately begun to draw the attention of the scientific community owing to the irreversible impact on the patient's quality of life. Here we tended to investigate the potential role of liraglutide (LRG) in modulating the canonical Hedgehog (Hh) signaling in doxorubicin (DXR)-induced gonadotoxicity in rats. Female virgin Wistar rats were divided into 4 groups; control, DXR-treated (25mg/kg, single i.p. injection), LRG-treated (150μg/Kg/day, s.c) and itraconazole (ITC; 150mg/kg/day, p.o)-pretreated group, as the Hh pathway inhibitor. Treatment with LRG potentiated the PI3K/AKT/p-GSK3β cascade and relieved the oxidative burden-induced by the DXR-driven immunogenic cell death (ICD). LRG also upregulated the expression of the Desert hedgehog ligand (DHh) and the patched-1 (PTCH1) receptor and augmented the protein level of Indian hedgehog (IHh) ligand, Gli1 and cyclin-D1 (CD1). Besides, hypertranscription of IHh, DHh, Ptch1, Smo, Gli1/2 and CD1 genes along with a transcriptional recession of Gli3 gene were reported in LRG-treated group. ITC pre-administration partially abrogated this positive effect of LRG, proving the implication of the examined pathway. Microscopically, LRG ameliorated the follicular atresia noticed in the DXR group; effect that was, at least partially, declined by ITC pre-treatment. These findings end to a conclusion that LRG treatment might hinder the DXR-associated reproductive toxicity, resultant from ROS generated by the cells undergoing ICD, and trigger follicular growth and repair by the PI3K/AKT- dependent switching-on of the canonical Hh pathway.

The impact of maternal obesity on in vivo uterine contractile activity during parturition in the rat.

Maternal obesity is associated with increased risk of prolonged and dysfunctional labor and emergency caesarean section. To elucidate the mechanisms behind the associated uterine dystocia, a translational animal model is required. Our previous work identified that exposure to a high-fat, high-cholesterol (HFHC) diet to induce obesity down-regulates uterine contractile associated protein expression and causes asynchronous contractions ex vivo. This study aims to investigate the impact of maternal obesity on uterine contractile function in vivo using intrauterine telemetry surgery. Virgin female Wistar rats were fed either a control (CON, n=6) or HFHC (n=6) diet for 6 weeks prior to conception, and throughout pregnancy. On Day 9 of gestation, a pressure-sensitive catheter was surgically implanted aseptically within the gravid uterus. Following 5 days recovery, intrauterine pressure (IUP) was recorded continuously until delivery of the 5th pup (Day 22). HFHC induced obesity led to a significant 1.5-fold increase in IUP (p=0.026) and fivefold increase in frequency of contractions (p=0.013) relative to CON. Determination of the time of labor onset identified that HFHC rats IUP (p=0.046) increased significantly 8h prior to 5th pup delivery, which contrasts to CON with no significant increase. Myometrial contractile frequency in HFHC rats significantly increased 12 h prior to delivery of the 5th pup (p=0.023) compared to only 3h in CON, providing evidence that labor in HFHC rats was prolonged by 9h. In conclusion, we have established a translational rat model that will allow us to unravel the mechanism behind uterine dystocia associated with maternal obesity.

Maternal Exposure to Acephate Caused Nephrotoxicity in Adult Offspring Rats Mediated by Excessive Autophagy Activation, Oxidative Stress Induction, and Altered Epithelial Sodium Channel and Na+/K+-ATPase Gene Expression

This study examined how maternal exposure to acephate-an organophosphate-based insecticide-affected the renal development in rat offspring during adulthood. Virgin female Wistar rats were randomly allocated to three groups: group 1 (control) received sterile water; groups 2 and 3 were intragastrically exposed to low (14 mg/kg) and high (28 mg/kg) doses of acephate from day 6 of pregnancy until delivery, respectively. Further, the offspring of the adult female rats were euthanized in postnatal week 8. Compared with the controls, the adult rat offspring with exposure to low and high doses of acephate exhibited elevated plasma creatinine and blood urea nitrogen levels. Additionally, immunofluorescence analysis revealed the upregulation of autophagic marker genes (Beclin-1 and LC-3) in the acephate-treated rat offspring, thereby suggesting the induction of an autophagic mechanism. Notably, the increased malondialdehyde level, decreased glutathione level, and decreased superoxide dismutase and catalase activities confirmed the ability of acephate to induce oxidative stress and apoptosis in the kidneys of the rat offspring. This may explain the renal histopathological injury detected using hematoxylin and eosin staining. Furthermore, a reverse transcription polymerase chain reaction revealed that the mRNA expression levels of the Na+/K+-ATPase and the epithelial sodium channel (ENaC) genes were significantly higher in the kidney of female offspring than that of controls owing to acephate toxicity. However, there was no significant effect of acephate on the expression of NHE3 in the treatment group compared with the control group. Overall, the present findings suggest that oxidative stress caused by prenatal exposure to acephate causes nephrotoxicity and histopathological alterations in adult rat offspring, likely by actions on renal ENaC and Na+/K+-ATPase genes as well as the autophagic markers Beclin-1 and LC-3.

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 ± 10g) were assigned into four groups: the groups received vehicle (control), acetate (200mg/kg), letrozole (1mg/kg) and letrozole plus acetate, respectively. The administrations were done concomitantly by oral gavage for 21days. 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.

Synthetic Oxytocin and Vasopressin Act Within the Central Amygdala to Exacerbate Aggression in Female Wistar Rats.

Exacerbated aggression is a high-impact, but poorly understood core symptom of several psychiatric disorders, which can also affect women. Animal models have successfully been employed to unravel the neurobiology of aggression. However, despite increasing evidence for sex-specificity, little is known about aggression in females. Here, we studied the role of the oxytocin (OXT) and arginine vasopressin (AVP) systems within the central amygdala (CeA) on aggressive behavior displayed by virgin female Wistar rats using immunohistochemistry, receptor autoradiography, and neuropharmacology. Our data show that CeA GABAergic neurons are activated after an aggressive encounter in the female intruder test. Additionally, neuronal activity (pERK) negatively correlated with the display of aggression in low-aggressive group-housed females. Binding of OXT receptors, but not AVP-V1a receptors, was increased in the CeA of high-aggressive isolated and trained (IST) females. Finally, local infusion of either synthetic OXT or AVP enhanced aggression in IST females, whereas blockade of either of these receptors did not affect aggressive behavior. Altogether, our data support a moderate role of the CeA in female aggression. Regarding neuropeptide signaling, our findings suggest that synthetic, but not endogenous OXT and AVP modulate aggressive behavior in female Wistar rats.

Effects of atorvastatin and resveratrol against the experimental endometriosis; evidence for glucose and monocarboxylate transporters, neoangiogenesis

The current study was conducted to investigate the therapeutic effects of atorvastatin (ATV) and resveratrol (RVT) in sole and simultaneous forms of administration against the symbiosis between glucose transporters 1 and 3 (GLUT-1 and GLUT-3), monocarboxylate transporters 1 a and 4 (MCT-1 and MCT-4) and neovascularization in ectopic endometrial tissue (EET). For this purpose, the experimental endometriosis was induced in 24 virgin female Wistar rats, and then the rats were divided into non-treated endometriosis-induced (ENDO-sole), AVT-treated (5 mg kg-1), RVT-treated (40 mg kg-1) and AVT +RVT-treated groups (n = 6 rats in each group). Following 28 days from the experimental endometriosis induction, the EETs were collected and the EETs size, neovascularization ratio, and expression levels of GLUT-1, GLUT-3, MCT-1, and MCT-4 were analyzed by qRT-PCR and immunohistochemistry (IHC). The AVT and RVT sole and simultaneous-treated animals exhibited decreased EET sizes and neovascularization. Moreover, the mRNA levels of GLUT-1, GLUT-3, MCT-1, and MCT-4, as well as GLUT-1+, GLUT-3+, and MCT-4+ cells distribution per mm2 of tissue were decreased in AVT and RVT sole and simultaneous-treated groups. Our findings showed that the AVT and RVT, especially in the simultaneous form of administration, could decrease the neovascularization development in the EETs by suppressing the GLUTs (1 and 3) and MCTs (1 and 4) expressions. Therefore, it can be concluded that the simultaneous administration of AVT and RVT can inhibit the EET's establishment and development through suppressing glycolysis and neovascularization.

Thyroxine Treatment During the Perinatal Stage Prevents the Alterations in the ObRb-STAT3 Leptin Signaling Pathway Caused by Congenital Hypothyroidism.

Thyroid hormone deficiency during crucial stages of development causes congenital hypothyroidism. This syndrome alters hypothalamic pathways involved in long-term bodyweight regulation as ObRb-STAT3 leptin signaling pathway, which is associated with metabolic syndrome. This study aimed to determine if thyroxine treatment during pregnancy and lactation in hypothyroid mothers avoids, in the congenital hypothyroid offspring, the alterations in metabolic programming related to metabolic syndrome and the ObRb-STAT3 leptin signaling pathway in hypothalamus. Twenty-four virgin female Wistar rats were divided into euthyroid, hypothyroid, and hypothyroid with thyroxine treatment (20 μg/kg/day T4 since pregnancy until lactation). The bodyweight and energy intake, insulin resistance, glucose tolerance, metabolic and hormonal parameters were determined in offspring at 28 weeks after birth. Then, the rats were euthanized to obtain adipose tissue reserves and hypothalamus to measure the expression of ObRb, STAT3, pSTAT3, and SOCS3. Congenital hypothyroidism presented metabolic syndrome such as insulin resistance, glucose tolerance, dyslipidemias, an increase in cardiovascular risk (Castelli I males:166.67%, females: 173.56%; Castelli II males: 375.51%, females: 546.67%), and hypothalamic leptin resistance (SOCS3, Males: 10.96%, females: 25.85%). Meanwhile, the thyroxine treatment in the mothers during pregnancy and lactation prevents the metabolic disturbance. In conclusion, thyroxine treatment during the critical perinatal stage for metabolic programming prevents congenital hypothyroidism-caused metabolic syndrome and hypothalamic leptin resistance.

Effects of troxerutin on inflammatory cytokines and BDNF levels in male offspring of high-fat diet fed rats.

Objective:In the present study, we aimed to examine the effect of troxerutin treatment on levels of brain-derived neurotrophic factor (BDNF), and tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), as pro-inflammatory cytokines, in the blood and hippocampus of high-fat diet (HFD) fed dams and their male offspring. Materials and Methods:Forty virgin female Wistar rats, 3 weeks old, were divided into two groups (n=20/per group) and fed control diet (CD), or HFD for 8 weeks. After mating, pregnant animals were assigned to four subgroups including: control (CD), control+troxerutin (CD+T), high-fat diet (HFD), and HFD+troxerutin (HFD+T) groups. HFD was continued during pregnancy and lactation. Troxerutin (150 mg/kg/day, P.O.) was administered during pregnancy in the CD+T and HFD+T groups. On postnatal day (PND) 21, male offspring were separated and fed a normal diet until PND 90. Inflammatory cytokines (TNF-α, and IL-6) and BDNF levels were measured in the serum and hippocampal samples using rat-specific enzyme-linked immunosorbent assay (ELISA) kits. Results:Our findings showed a significant increase in the serum levels of TNF-α and IL-6, but a decrease in BDNF levels in the serum of HFD-fed dams in comparison with CD group, which was reversed by troxerutin. Moreover, troxerutin treatment, during pregnancy, significantly decreased TNF-α and IL-6 levels, but increased BDNF level in the serum and hippocampus of HFD+T offspring in comparison with HFD offspring. Conclusion:These results showed that troxerutin could prevent the harmful effects of maternal HFD on their offspring through inhibition of pro-inflammatory cytokines and elevation of BDNF levels.

Histopathological Analysis and Scanning Electron Microscopic Study of Chlorpyrifos Exposed Kidney of Neonates in Pregnant Rats Exposed During Gestation Period

Background: Pesticide exposure has the potential for causing acute or chronic health effects at certain developmental stages of life. It can result in irreversible damage to structure and function of an organ. The exposure of females to pesticides before or after pregnancy is a matter of concern because of the possibility of having a child born with congenital disorders and developmental defects. Prenatal exposure of any toxicants can program the developing foetus to develop diseases that manifest in later life. Very few reports are available related to the pesticide exposure induced morphological changes in kidney which has prompted us to undertake this research study. Aim: The aim of this study is to evaluate the effect of pesticide, chlorpyrifos on the kidney development of rat neonates after being exposed prenatally to pesticides throughout their gestational period. Materials and Methods: Virgin female wistar rats weighing 200-250 gms were mated with adult males. It consisted of twelve, divided into two sub groups six rats per each were treated with selected pesticides, chlorpyrifos (insecticide) readily available commercially for various agricultural and non-agricultural settings. Insecticide chlorpyrifos was given at a dose of 10mg/kg per orally to the female rats throughout their gestation period. After gestation period rat neonates were sacrificed and their kidney section was processed for histopathological analysis. The SEM study of chlorpyrifos exposed kidney section of rat neonates was performed, investigating changes in morphometric and ultra-structural features of kidney in rat neonates. Results: The histopathological analysis shows morphological changes in the kidneys of prenatally pesticides exposed rat neonates markedly different from control group. Chlorpyrifos exposed neonates kidney shows damaged kidney corpuscles and glomeruli. Conclusion: This study concluded that pesticide exposure during gestation period to pregnant rats causes significant renal toxicity in their neonates.

Impact of Metformin and Pioglitazone on Serum Level of Tumor Necrosis Factor-Alpha and Lipid Profiles during Implantation Window in Diabetic Rats.

BackgroundThe present study was designed to evaluate serum lipid profile and tumor necrosis factor-alpha (TNF-ɑ) level in diabetic rats at implantation time. Type 2 diabetes mellitus (T2DM) could affect various systems, including innate immune system and it causes chronic low-grade inflammation, increasing level of TNF-ɑ. Furthermore, T2DM is often accompanied by impaired lipid profile. Metformin and pioglitazone are used as the first and second lines of treatment for T2DM.Materials and MethodsIn this experimental study, 35 adult virgin female wistar rats, weighting 175-225 g, were randomly categorized into five groups: i. Control, ii. Sham, iii. Nicotinamide (NA)+streptozotocin (STZ) induced T2DM, iv. Diabetic+pioglitazone (20 mg/kg/day for 28 days oral administration), and v. Diabetic+metformin (100 mg/kg/day for 28 days oral administration). At the time of implantation, TNF-ɑ level in serum of rats was measured by ELISA kit. Glucose was measured using photometric method and lipid profiles were calculated by enzymatic methods.ResultsLevel of TNF-ɑ in the diabetic group was significantly higher than other groups (P<0.001). In metformin treated group, TNF-ɑ serum level was also significantly higher than pioglitazone treated group (P<0.001). Fasting blood sugar (FBS) and lipid profiles were significantly higher in diabetic group.ConclusionMetformin and pioglitazone have similar effects on glucose, lipid profiles and TNF-ɑ serum levels. Among these drugs, pioglitazone has more efficient influence on TNF-α serum level, in comparison with metformin.

Maternal Response of Perinatally Underfed Wistar Virgin Females Exposed to Newborn Rats

Nutrition plays a major role in the survival of the progeny, and its perinatal deficiencies delay physical development and interfere with social and cognitive performance later in life. The effects of early undernutrition on maternal social performance of sensitized adult virgin rats were evaluated. Several maternal and non-maternal responses were measured in virgin female Wistar rats randomly divided into two groups, control and early undernourished, during 19 days of chronic daily exposure to fresh foster pups in home-cage conditions. Underfed females (F0) received different percentages of a balanced diet during gestation. After birth, pups were underfed (F1) by alternating every 12 h between litters two lactating dams, one with ligated nipples. Weaning was at 25 days of age followed by an ad lib diet until postpartum day 90, when sensitized virgins were maternally tested daily for seven successive sessions. Significantly (p < 0.05) low body weight scores in UG F1 virgins of five different ages were observed. The UG F1 females expressed significantly (p < 0.05) lower frequency values in sniffing, licking, retrieving, crouching, and handling shavings, with clear prolonged sniffing, retrieving and handling shaving latencies towards the foster pups compared with CG F1 sensitized females. Self-grooming was not affected, whereas exploration was significantly reduced. Current findings suggest that perinatal undernutrition interfered the organization of a core neuronal circuitry underlying the mother-litter interactions involved in social and cognitive performance of sensitized adult virgins. Furthermore, the behavioral maternal alterations in F1 virgins may possibly generate a risky negative social environment to induce cognitive and/or brain disorders in later generations.

Effect of enriched environment during adolescence on spatial learning and memory, and voluntary consumption of morphine in maternally separated rats in adulthood.

This study was designed to examine the effect of environmental enrichment (EE) during adolescence on spatial learning and memory and voluntary morphine consumption in maternally separated (MS) male and female rats in adulthood. Male Wistar rats were allowed to mate with female virgin Wistar rats. Pups were separated from the dams daily for 180min during postnatal days 2-14. All pups were weaned on day 21. The pups of both sexes were reared in a standard (SE) or enriched (EE) environment during postnatal days 21-50. Then, adulthood rats were tested for spatial learning and memory (Morris Water Maze), and voluntary consumption of morphine using a two-bottle choice paradigm (TBC). We found that the MS/SE rats showed longer escape latencies to find the platform on the third (the male) and fourth (the female) days of training than No MS/SE rats. Also, exposure to EE shortened the latency to escape in the male and female MS rats as training progressed than MS/SE rats. Moreover, the No MS/EE and MS/EE male rats spent significantly more time in the target zone compared with the SE control groups in the probe test. We also found that voluntary morphine consumption was higher in the male and female MS/SE than No MS/SE rats, while it was lower in the male and female MS/EE rats. The present results have shown that EE treatment may have potential therapeutic application for the prevention of the development of drug addiction and recovery from cognitive deficits following neonatal MS during adulthood.

Lactation diminishes lesion-induced permeability of tracers into the brain

Diminished sensitivity to kainic acid (KA) lesioning action is present in the hippocampus of the lactating dam. Given that KA can alter blood-brain barrier (BBB) permeability, we investigated whether lactation would protect BBB permeability after treatment with this neurotoxin. Adult virgin or lactating (13–15 days pp) female Wistar rats were injected with an i.p. (10 mg/kg b.w.) or i.c.v. (100 ng/1 μl) KA dose. Control groups received a similar volume of vehicle. BBB permeability was assessed by an injection of fluorescent FITC-conjugated dextran tracer (40 kDa, 50 mg/500 μl) or of 4% Evans blue dye (500 μl), given 24 h after KA administration. Extravasation of dye or tracer was detected in virgin but not in lactating rats exposed to KA. In particular, increased extravasation of FITC-dextran was detected in the hippocampal subfields CA1 and CA3 and in the cerebral cortex of virgin rats that received KA, while lactating rats showed increased label for FITC-dextran only in the cerebral cortex. Western blot analysis of tight junction proteins showed a decrease of claudin-5 and occludin but not of zonula occludens-1 in the hippocampus of both virgin and lactating rats. These results allow us to conclude that the BBB of lactating rats is less sensitive to KA lesioning action in comparison to that of virgin rats by mechanisms different than those of tight junction proteins.

Zinc Alleviates Lipopolysaccharide Interference with Both Body Temperature and Sickness Behavior in Virgin Female Rats

Objectives: Previous studies from our group showed that lipopolysaccharide (LPS) exposure induces several signs of sickness behavior, including a decrease in food consumption, body weight gain, adipsia, and a biphasic effect in tympanic temperature with a first phase of hypothermia, followed by an increased tympanic temperature. LPS can activate a chain of nonspecific host responses, including the immune response, and decreased zinc levels. In addition, there are differences in the immune response between males and females, particularly fever, with sex hormones interfering with body temperature. This study aims to characterize the effects of zinc treatment on tympanic temperature, body weight gain, food and water consumption, and general activity in open field of virgin female rats exposed to a dose of LPS that was previously reported to induce sickness behavior. Methods: Virgin female Wistar rats were treated with either saline (S) or LPS. One hour later, the S group received another injection of saline (S + S group), half of the LPS group received saline (LPS + S group) and the other half received zinc (LPS + Zn group). Tympanic temperature, body weight, and water and food consumption were measured for 96 h. Measurements and observations started 2 h after LPS administration. Results: Treatment with zinc attenuated LPS-increased temperature, decreased the body weight gain and food consumption, and water consumption was increased. Conclusion: Zinc treatment is beneficial as it reduces the increased tympanic temperature induced by LPS, but it does not influence other sickness behavior caused by exposure to LPS.