Nonpregnant Rats Research Articles

Vasodilator Responses of Perivascular Adipose Tissue-Derived Hydrogen Sulfide Stimulated with L-Cysteine in Pregnancy Hypertension-Induced Endothelial Dysfunction in Rats.

Endothelium-derived nitric oxide (NO)-induced vasodilation is impaired in pregnancy hypertension. However, the role of perivascular adipose tissue (PVAT)-derived hydrogen sulfide (H2S), as an alternative for counteracting vascular dysfunction, is incompletely clear in hypertensive disorders of pregnancy. Therefore, PVAT-derived H2S-induced vasodilation was investigated in pregnancy hypertension-induced endothelial dysfunction. Non-pregnant (Non-Preg) and pregnant (Preg) rats were submitted (or not) to the deoxycorticosterone (DOCA)-salt protocol and assigned as follows (n = 10/group): Non-Preg, Non-Preg+DOCA, Preg, and Preg+DOCA groups. Systolic blood pressure (SBP), angiogenesis-related factors, determinant levels of H2S (PbS), NO (NOx), and oxidative stress (MDA) were assessed. Vascular changes were recorded in thoracic aortas with PVAT and endothelium (intact and removed layers). Vasorelaxation responses to the substrate (L-cysteine) for the H2S-producing enzyme cystathionine-γ-lyase (CSE) were examined in the absence and presence of CSE-inhibitor DL-propargylglycine (PAG) in thoracic aorta rings pre-incubated with cofactor for CSE (pyridoxal-5 phosphate: PLP) and pre-contracted with phenylephrine. Hypertension was only found in the Preg+DOCA group. Preg+DOCA rats showed angiogenic imbalances and increased levels of MDA. PbS, but not NOx, showed increased levels in the Preg+DOCA group. Pre-incubation with PLP and L-cysteine elevated determinants of H2S in PVAT and placentas of Preg-DOCA rats, whereas no changes were found in the aortas without PVAT. Aortas of Preg-DOCA rats showed that PVAT-derived H2S-dependent vasodilation was greater compared to endothelium-derived H2S, whereas PAG blocked these responses. PVAT-derived H2S endogenously stimulated with the amino acid L-cysteine may be an alternative to induce vasorelaxation in endothelial dysfunction related to pregnancy hypertension.

Inhibitory effect and underlying mechanism of essential oil of Prangos ferulacea Lindl (L.) on spontaneous and induced uterine contractions in non-pregnant rats

Evidence suggests the use of natural compounds as support in the management of uterine contractility disorders. We recently demonstrated that the essential oil of Apiacea Prangos ferulacea (L.) (Prangoil) modulates intestinal smooth muscle contractility. Thus, we aimed to evaluate if Prangoil could also affect the contractility of uterine muscle in non-pregnant rat and to investigate the related action mechanism/s. The effects of the aromatic monoterpenes, β-ocimene and carvacrol, constituents of Prangoil, were also evaluated. Spontaneous contractions and contraction-induced by K+-depolarization and oxytocin in rat uterus were recorded in vitro, using organ bath technique. Prangoil reduced the amplitude of spontaneous contractions as well as responses to KCl and oxytocin. β-ocimene and carvacrol matched oil inhibitory effects. Prangoil effects were not affected by nitrergic and adenylyl cyclase inhibitors or non-specific potassium channel blocker, but they were reduced by nifedipine, L-type calcium channel inhibitor, or 2-aminoethoxydiphenylborate (2-APB), membrane-permeant inositol 1,4,5-triphosphate receptor inhibitor. The response to β-ocimene was reduced by nifedipine and by 2-APB (20 μM), whilst carvacrol inhibitory effect was attenuated only by nifedipine. In conclusion, Prangoil, and its components, β-ocimene and carvacrol, reduced spontaneous and KCl or oxytocin-induced contractions of rat myometrium, mainly modulating extracellular Ca2+ influx through L-Type channels and Ca2+ release from the intracellular store. Further studies could contribute to evaluate the potential use of Prangoil against disorders characterized by abnormal uterine contractions.

Impact of Normal and Overweight Pregnancy in GLUT4 and Glucose-Dependent Vascular Contractility

Introduction: Obesity during pregnancy can contribute to hypertensive complications through changes in glucose utilization. We investigated the impact of vascular glucose uptake, GLUT4 density, and endothelium on agonist-induced vasoconstriction in the aortas of overweight pregnant rats. Methods: Isolated aortic rings with or without endothelium from pregnant or nonpregnant rats fed a standard (SD) or hypercaloric diet (HD) were contracted with phenylephrine or serotonin (10−9 to 10−4M) using standard (11 mm) or without (0 mm) glucose Krebs solution. GLUT4 density in the aortas was measured using the en face method. Results: Aortas from overweight pregnant animals (PHD) showed increased Phe-induced vasoconstriction (p < 0.05 vs. pregnant standard diet [PSD]), which was endothelium-independent. The contraction decreased significantly in the absence of glucose. In contrast, vessels from pregnant SD rats maintained their contraction in glucose-free Krebs solution. 5-HT increases PHD aortic contraction only in the absence of glucose. The fetal aortas from PHD mothers showed blunted vasoconstriction. Overweight significantly reduced GLUT4 expression in maternal and fetal aortas (p < 0.05 vs. PSD). Conclusions: Aortic contractility is independent of glucose uptake during healthy pregnancy. In contrast, overweight pregnancy increases contractility. This increase depends directly on smooth muscle glucose uptake and inversely on GLUT-4 density. The increased contraction observed in the vasculature of overweight mothers was inverted in the fetal aortas.

Does the addition of metformin to carboplatin treatment decreases ovarian reserve damage associated with carboplatin usage?

BackgroundWe aimed to determine whether adding metformin to carboplatin treatment would reduce the damage to ovarian reserve associated with carboplatin use.MethodsWe included 35 adult female non-pregnant albino Wistar rats approximately three months old, weighing 220–310 g. The rats were divided into five groups of seven rats according to the treatment they received. Carboplatin and salin was given to Group 2, and carboplatin plus metformin was given to Group 3. Group 4 was administered only metformin. Group 5 was administered only salin. Carboplatin was given to Groups 2 and 3 as a single dose on the 15th day, while metformin was given to Groups 3 and 4 during the 28-day experiment. After oophorectomy, histopathologic analyses of primordial, primary, secondary, and tertiary Graff follicles according to the epithelial cells surrounding the oocyte and total follicular number were conducted per section. Serum Anti-Mullerian Hormone (AMH), tissue catalase, and malonyl dialdehyde levels were measured and compared within each group.ResultsThe baseline and 15th-day serum AMH values of the menstrual cycle were compared among the groups, and no statistically significant differences were observed (p > 0.05). Group 3, which was given both carboplatin and metformin, had statistically significantly higher 28th-day AMH levels than Group 2, which was given only carboplatin and saline (p < 0.001). The number of primordial follicles in Group 3 was found to be statistically significantly higher than in Group 2 (p < 0.001). Tissue catalase enzyme levels in Group 3 were statistically significantly higher than in Group 2 (p < 0.001). Tissue malondialdehyde levels in Group 2 were statistically significantly higher than tissue malondialdehyde levels in Groups 3 and 4 (p < 0.001).ConclusionsMetformin may attenuate carboplatin-induced ovarian damage, possibly through its antioxidative effects.

Bushen Huoxue formula for the treatment of diminished ovarian reserve: A combined metabolomics and integrated network pharmacology analysis

ObjectiveThis study aimed to explore the mechanism of the Bushen Huoxue Formula (BHF) in treating diminished ovarian reserve (DOR) through the use of metabolomics and integrated network pharmacology. MethodsThe study involved 24 non-pregnant female Sprague-Dawley rats, divided into four groups of six rats each: control, model, BHF, and DHEA (n = 6 per group). The model group was induced with DOR by administering Tripterygium glycosides orally [50 mg (kg·d)−1] for 14 days. Subsequently, BHF and Dehydroepiandrosterone (DHEA) treatments were given to the respective groups. Ovarian reserve function was assessed by measuring anti-Müllerian hormone (AMH), estradiol (E2), and follicle-stimulating hormone (FSH) levels and conducting hematoxylin-eosin staining. In addition, UHPLC-QTOF-MS analysis was performed to identify differential metabolites and pathways in DOR rats treated with BHF. In this study, LC-MS was utilized to identify the active ingredients of BHF, while network pharmacology was employed to investigate the correlations between BHF-related genes and DOR-related genes. An integrated analysis of metabonomics and network pharmacology was conducted to elucidate the mechanisms underlying the efficacy of BHF in treating DOR. ResultsThe model group exhibited a poor general condition and a significant decrease in the number of primordial, primary, and secondary follicles (P < 0.05) when compared to the control group. However, BHF intervention resulted in an increase in the number of primordial, primary, and secondary follicles (P < 0.05), along with elevated levels of AMH and E2 (P < 0.05), and a decrease in FSH levels (P < 0.05) in DOR rats. The modeling process identified eleven classes of metabolites, including cholesterol esters (CE), diacylglycerols (DAG), hexosylceramides (HCER), lysophosphatidylcholines (LPC), phosphatidylcholines (PC), phosphatidylethanolamines (PE), sphingomyelins (SM), ceramides (CER), free fatty acids (FFA), triacylglycerols (TAG), and lysophosphatidylethanolamines (LPE). The study found that PC, CE, DAG, and TAG are important metabolites in the treatment of DOR with BHF. LC-MS analysis showed that there were 183 active ingredients in ESI(+) mode and 51 in ESI(−) mode. Network pharmacology analysis identified 285 potential genes associated with BHF treatment for DOR in ESI(+) mode and 177 in ESI(−) mode. The combined analysis indicated that linoleic acid metabolism is the primary pathway in treating DOR with BHF. ConclusionBHF was found to improve ovarian function in rats with DOR induced by Tripterygium glycosides. The study identified key metabolites such as phosphatidylcholine (PC), cholesteryl ester (CE), diacylglycerol (DAG), triacylglycerol (TAG), and the linoleic acid metabolism pathway, which were crucial in improving ovarian function in DOR rats treated with BHF.

Thapsigargin-resistant thiacalix[4]arene C-1087-sensitive component of the contractile activity in rat myometrium reflects the functioning of plasma membrane calcium pump

Background. According to existing knowledge, thiacalix[4]arene С-1087 is highly capable of inhibiting Са2+-pump (Са2+, Mg2+-АТРase) of the plasma membrane; at the same time it inhibits the functioning of Са2+-pump of the sarcoplasmic reticulum of uterine smooth muscles to some degree. The aim of this research was to study the effects of С-1087 on the concentration of Ca2+ ions and contractile activity of the rat myometrium cells using an inhibitor of Са2+-pump of the sarcoplasmic reticulum – thapsigargin. Materials and Methods. The experiments were conducted using outbred white non-pregnant rats. The contractile activity in the preparations of longitudinal SM of uterine horns with preserved endothelium was registered in the isometric mode. To determine the changes in [Ca2+]i level, myocytes were treated with probes Hoechst 33342 (to test the nucleus of the cell) and fluo-4 AM (to test the change in Са2+-concentration in the cell). Results. The tenzometric studies with the subsequent mechanokinetic analysis demonstrated that under the action of thapsigargin (0.5 µM), thiacalix[4]arene C-1087 (10 µM) caused considerable changes in the kinetics of the spontaneous contractile activity processes in the myometrium of rats, including the decrease in the maximal contraction velocity and the increase in the maximal relaxation velocity. By means of confocal microscopy with Ca2+-sensitive fluorescent probe fluo-4, it was demonstrated that the application of thiacalix[4]arene С-1087 to immobilized myocytes of the uterus against the background of thapsigargin caused a transient spike of Са2+-signal with the subsequent turn of the intracellular concentration of Ca ions to the stable increased level. The effects of С-1087 under the action of thapsigargin regarding the relaxation phase in the spontaneous myometrium contractions were removed after the preliminary blocking of nitric oxide synthases L-NAME (100 µM). Under the action of L-NAME, thiacalix[4]arene С-1087 (10 µM) caused complete inhibition of the relaxation process in the contraction of myometrium preparations, induced by high-potassium solution (80 mM). Conclusions. The primary reason for changes in the contractile activity and Ca2+-signal in uterine myocytes under the effect of thiacalix[4]arene С-1087 is its ability to inhibit Са2+-pump of the plasma membrane; further С-1087-induced changes in the smooth muscle tissues may be caused by the increased level of Са2+ concentration in myocytes. The obtained results demonstrate thiacalix[4]arene С-1087 is a promising compound for the elaboration of pharmacological preparations for modulating the contractile activity in smooth muscles, including myometrium.

Rapid gastric emptying during pregnancy in a rat model

Background/aimsThe effect of pregnancy on gastric emptying has not been established, although the predominant clinical assumption is that gastric emptying is delayed during pregnancy. We hypothesized that the rate of emptying of nutrients during pregnancy is not delayed, but is actually more rapid when compared to the non-pregnant state. The rate of gastric emptying is a major determinant of postprandial glucose elevations. Materials and methods24 female and 4 male Spague-Dawley rats were used. Female rats were randomly divided into two groups: eight rats for the control group and sixteen rats for the pregnant group. Using physiologic, non-traumatic nuclear medicine scintigraphy imaging methodology, the authors studied gastric emptying of a liquid mixed meal in pregnant rats and non-pregnant controls. Body weights, daily food ingestion, and the rate of nutrient gastric emptying were recorded in both groups at pre-pregnancy, early pregnancy, and late pregnancy. ResultsThe authors found that pregnancy in this rat model is associated with a 37–43% increased rate of nutrient gastric emptying from the stomach in late pregnancy as compared to non-pregnant control rats and pre-pregnancy rats. ConclusionThese findings contradict the current clinical assumption that gastric emptying is delayed in pregnancy. If further studies confirm a more rapid gastric emptying rate during human pregnancy, new therapies aimed at slowing the rate of nutrient absorption should be considered for the prevention and treatment of pregnancy-associated nausea, gestational diabetes, and other insulin-resistant pregnancy-associated states such as pre-eclampsia.

Synergistic regulation of uterine radial artery adaptation to pregnancy by paracrine and hemodynamic factors.

Fetal growth throughout pregnancy relies on delivery of an increasing volume of maternal blood to the placenta. To facilitate this, the uterine vascular network adapts structurally and functionally, resulting in wider blood vessels with decreased flow-mediated reactivity. Impaired remodeling of the rate-limiting uterine radial arteries has been associated with fetal growth restriction. However, the mechanisms underlying normal or pathological radial artery remodeling are poorly understood. Here, we used pressure myography to determine the roles of hemodynamic (resistance, flow rate, shear stress) and paracrine [β-estradiol, progesterone, placental growth factor (PlGF), vascular endothelial growth factor] factors on rat radial artery reactivity. We show that β-estradiol, progesterone, and PlGF attenuate flow-mediated constriction of radial arteries from nonpregnant rats, allowing them to withstand higher flow rates in a similar manner to pregnant vessels. This effect was partly mediated by nitric oxide (NO) production. To better understand how the combination of paracrine factors and shear stress may impact human radial artery remodeling in the first half of gestation, computational models of uterine hemodynamics, incorporating physiological parameters for trophoblast plugging and spiral artery remodeling, were used to predict shear stress in the upstream radial arteries across the first half of pregnancy. Human microvascular endothelial cells subjected to these predicted shear stresses demonstrated higher NO production when paracrine factors were added. This suggests that synergistic effects of paracrine and hemodynamic factors induce uterine vascular remodeling and that alterations in this balance could impair radial artery adaptation, limiting blood flow to the placenta and negatively impacting fetal growth.NEW & NOTEWORTHY Placenta-specific paracrine factors β-estradiol, progesterone, and placental growth factor attenuate flow-mediated constriction of the rate-limiting uterine radial arteries, enabling higher flow rates in pregnancy. These paracrine factors induce their actions in part via nitric oxide mediated mechanisms. A synergistic combination of paracrine factors and shear stress is likely necessary to produce sufficient levels of nitric oxide during early human pregnancy to trigger adequate uterine vascular adaptation.

Abstract P2126: Role Of Microrna-98 In Myocardial Ischemia-reperfusion Injury In Late Pregnancy

Background: We have shown that the late-pregnant (LP) rodent is more vulnerable to myocardial ischemia-reperfusion injury (IRI) compared to non-pregnant (NP). The molecular mechanisms are unknown. Several microRNAs (miRs) are dysregulated in IRI, making them promising therapeutic targets. Methods: The left anterior descending coronary artery (LAD) of female Sprague-Dawley rats (2-3 months old NP and LP, 20-21 days pregnant) was occluded for 45 minutes followed by 3 hours reperfusion. Myocardial necrosis was assessed using TTC staining. MicroRNA-microarray profiling was performed on hearts of NP and LP rats subjected to IRI. In vitro, female cardiomyocytes were transfected either miR98 mimic or inhibitor, followed by 3 hours hypoxia and 6 hours reoxygenation. Blood samples were collected from NP, LP, and coronary heart disease (CHD) patients. To assess therapeutic potential of miR, miR98 inhibitor was administered at the onset of reperfusion. Results: MicroRNA-microarray profiling revealed miR-98-5p (miR-98) is upregulated in the hearts of LP IRI rats compared to NP IRI by 2.3 folds, which we confirmed with qPCR. miR98 is significantly increased in the plasma of healthy LP compared to healthy NP women, and significantly increased in LP with CHD compared to healthy LP. TargetScan revealed STAT3 and PGC-1α to be targets of miR98. We confirmed significantly decreased expression of STAT3 and PGC-1α in LP IRI rat myocardium compared to NP IRI. MiR98 overexpression in female cardiomyocytes subjected to hypoxia/reoxygenation (H/R) decreased STAT3 and PGC-1α, and increased apoptosis, inflammation, and oxidative stress, while miR-98 knockdown resulted in the opposite effect. Therapeutic targeting of microRNA-98-5p in LP rats subjected to IRI reduced infarct size, apoptosis, oxidative stress, and inflammatory markers via upregulating Stat3 and Pgc-1α. Conclusions: MiR98 is upregulated in LP rats subjected to IRI compared to NP IRI and in LP human plasma samples with CHD compared to healthy NP and LP. miR98 promotes oxidative stress, inflammation, and apoptosis in the setting of H/R in vitro by targeting STAT3 and PGC-1α. Inhibition of miR-98 in LP rats reduces myocardial infarct size, apoptosis, oxidative stress, and inflammation via Stat3 and Pgc-1α.

Evaluation of Safety Profile of Costus Pictus D Don Methanolic Leaf Extract on Albino Wistar Rats

With the emerging trend of preferring naturopathy over modern medicine, common people are in more danger when consuming natural plant products without the knowledge of the toxic agents present in them. Aim and Objective: To evaluate the safety of methanolic leaf extract of Costus pictus D Don on albino Wistar rats. Methodology: The current study was designed strictly based on the organization for economic cooperation and development (OECD) guideline 423 for acute toxicity study to determine LD50 and guideline 407 for sub-acute toxicity study for hazard identification and risk assessment of the test solution. Methanolic leaf extract was prepared by soxhlation. 12 animals (each 12-week-old nulliparous, non-pregnant female Wistar rats with a mean weight of 142 ± 2 g), 3 per step were used for the acute toxicity study. The test was initiated with a single test dose of 300 mg/kg BW on three animals and continued till 2000 mg/kg BW. After ingesting the test dose each animal was observed individually for the first 4 hours and later every day for 2 weeks for signs of toxicity. For the sub-acute toxicity study, 30 adult Wistar rats (each 16-week-old rat weighing 250±12g) were randomized into 3 groups (1 control and 2 study groups) of 10 each consisting of five males and 5 females. Animals in the control group received 1% Carboxymethyl cellulose (CMC) at a dose of 10 ml/kg BW whereas the animals in the study group received 500 and 1000 mg/kg body weight (BW) of the extract respectively for 28 days. Later, all the animals were sacrificed and blood samples were studied for hematological and biochemical changes. Results: The lethal dose of Costus pictus D Don methanolic leaf extract was fixed as more than 2000 mg/kg Body weight. No obvious change was observed in feeding habits, weight, hematology, biochemical parameters, and histopathology. Conclusion: Methanolic leaf extract of Costus pictus D Don was observed to be absolutely safe when given orally in albino Wistar rats.

Heat Stress Induces Oxidative Stress and Predisposes Rats to Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is a form of hyperglycemia due to carbohydrate intolerance that begins during pregnancy. This may be due to insulin resistance or impairment of insulin secretion during the pregnancy. Several causes of GDM have been identified which include oxidative stress (OS), however the association of heat stress and GDM development during pregnancy is limited. Therefore, this study aimed at examining the association between heat stress and GDM in rats. Pregnant and non-pregnant Wistar rats were maintained at 41 - 42°C for 21 days. On day 1, 8, 15 and 21 of the experiment, animals were humanely sacrificed. Blood samples for glucose, insulin, malondialdehyde (MDA) and glutathione peroxidase (GPx) analyses were collected from the heart. Pancreatic tissues were fixed in neutral buffered formalin, and processed for histopathological studies. The findings demonstrated that, in pregnant rats, heat stress induced a significant increase in glucose linked with a drop in insulin levels than non-pregnant rats (P &lt;0 .05). Also heat treatment was accompanied by an increase in MDA and a drop in GPx levels. Histological examinations of the pancreas revealed damaged β-cells on day 15 and reduction in the number of β-cells by day 21 of the experiment in the pregnant rats. These results suggest that heat stress raises the levels of OS in pregnant rats than non-pregnant rats and increases the chance of GDM as it is associated with β-cell defects in the pancreas.

Profile of maternal serum oxytocin in postpartum and non-pregnant rats

Oxytocin is primarly secreted in the brain as a neuromodulator that affects numerous neurophysiological and behavioral processes. It is also produced in the ovaries and uterus to stimulate delivery and lactation. Oxytocin mRNA is found in the endometrial epithelial cells of non-pregnant women during ovulation and menstruation. Until recently, there have been no data on scientific-level oxytocin in virgin female rats. This study aimed to compare the level of oxytocin in different physical biology between postpartum and non-pregnant experimental animals (virgin or had never given birth). This experimental study was conducted on 19 female white rats (Rattus norvegicus) allocated to two groups: T1 and T2. The ten rats in group T1 (nulliparous virgin) and the nine in group T2 (postpartum) were sacrificed on day two, except for group T1, which were sacrificed following vaginal delivery. Blood was collected intracardiacally, and serum oxytocin levels were evaluated using an ELISA assay. The T-test was used for statistical data analysis. The serum oxytocin level in the T2 group (628.06 ± 168.72 pg/mL) was significantly higher than in the T1 group (366.71 ± 185.03 pg/mL; P &amp;lt; 0.05). In conclusion, oxytocin levels were higher in postpartum animals than in virgin animals. Thus, oxytocin plays a greater role in female reproduction than in normal physiological condition.

Prolonged stretching of rat uteri causes hypoxia and inhibits contractility via potassium channel TREK1.

During pregnancy, uterine kept quiescence along with uterine overdistention before labor. Prolonged stretching induced uterus myometrial hypoxia, increased TREK1 expression, and relaxed the myometrium, which may contribute to uterine quiescence and atony during pregnancy. The mechanisms underlying pre-labor uterine quiescence and uterine atony during overdistention are unclear. TREK1 (a two-pore domain potassium channel) and hypoxia-inducible factor-1α (HIF-1α) are activated by mechanical stretch, and their expression is upregulated by decreased uterine contractility. HIF-1α is a nuclear factor which regulates numerous target proteins, but whether it regulates TREK1 during the uterine stretch to cause uterine quiescence and/or atony is unclear. We investigated uterine contractility at different gestational stages in rats, as well as in non-pregnant uteri, which were induced by prolonged stretching and hypoxia. We also assessed the effects of incubating the uteri with or without echinomycin or l-methionine. Moreover, we analyzed HIF-1α and TREK1 expression levels in each group, as well as at various gestational stages of pregnant human uteri. We found that contractility was significantly decreased in pregnant uteri when compared with non-pregnant uteri, and this decrease was associated with increases in HIF-1α and TREK1 expression levels. HIF-1α and TREK1 expression levels in human uteri increased with the gestational length. Decreased uterine contractility and increased HIF-1α and TREK1 expression levels were also observed in non-pregnant rat uteri under 8 g of stretching tension or hypoxia. Inhibition of hypoxia with echinomycin restored normal uterine contractility, while HIF-1α and TREK1 protein expression remained reduced. TREK1 inhibition with l-methionine also restored uterine contractility under tension or hypoxia. In conclusion, we demonstrated that prolonged stretching induces myometrial hypoxia, increases TREK1 expression, and relaxes the myometrium, which may contribute to uterine quiescence and atony.

Role of preeclampsia on insulin-induced vasorelaxation

The objective of this project was to evaluate whether PE alters the vascular response to insulin. The physiological insulin resistance characteristic of pregnancy is increased in preeclamptic (PE) conditions. With the hypothesis that PE diminishes insulin vascular effects we used a conventional isolated aorta rings preparation to study insulin-induced relaxation on phenylephrin (Phe) pre-contracted vessels and Phe induced contraction in the presence or absence of insulin. Vessels were obtained from non-pregnant rats (NP) with subrenal aortic coarctation (SRAC), pregnant (P) and pregnant rats with SRAC (PE). Experiments were performed in thoracic or abdominal aorta rings with or without endothelium. The results show that PE increases the contractile response to Phe in the thoracic and abdominal aorta compared to P (PE vs P p&lt;0.01). Incubation with insulin did not modify the thoracic or abdominal aorta Phe induced contraction of any of the three groups with and without endothelium.On the other hand, insulin induced relaxation was more evident in vessels with endothelium and was decreased both in the thoracic and the abdominal aorta of PE group (PE vs P p&lt;0.01; PE vs NP-CARS p&lt;0.01).In conclusion, PE decreases endothelium-dependent insulin-induced relaxation suggesting PE deteriorates insulin-PI3K-NO pathway. Funding: Consejo Nacional de Ciencia y Tecnología(CONACyT) This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Prenatal Developmental Oral Toxicity Evaluation of Defatted Fenugreek Seed Flakes (FenuflakesTM) in Laboratory Rats

Fenugreek seed-based ingredients showed potential health benefits towards female-specific conditions. The present work is aimed to assess the prenatal oral toxicity of fibers and protein rich defatted fenugreek seed flakes (Fenuflakes™). The acute oral toxicity and dose range-finding studies in non-pregnant and pregnant rats were conducted before the main study. The selected doses of Fenuflakes (500, 1000, and 2000 mg/kg) were orally gavaged to rats daily from day 0 to day 19 (one day before the expected day of parturition) post-conception with the concurrent vehicle control (VC) group. On the 20th day of gestation, the maternal and embryo-fetal toxicity parameters were recorded after the cesarean sections of dams. Results: Fenuflakes in tested doses exposure did not show significant toxicological changes in maternal (body weights, food intake, anogenital distance, or clinical observations) and embryo-fetal evaluations (number of corpora lutea, resorptions, and implantations, or fetus weights, sex ratio or incidence of anomalies) compared with VC. Conclusion: Oral prenatal exposure to Fenuflakes was found safe with no significant maternal and embryo-fetal toxicities. The "No Observed Adverse Effect Level” (NOAEL) of Fenuflakes (&gt; 2000 mg/kg/day) can be used for risk assessment before human consumption in pregnant female population.

English

Gestational diabetes mellitus (GDM) is a glucose intolerance resulting in hyperglycemia with onset or first recognition during pregnancy. High fat diet (HFD) is one of the contributing factors to GDM. This study evaluated the contribution of HFD in differential adipose tissue (AT) expansion and subsequent development of GDM in Wistar rats. Pregnant and non-pregnant rats were given streptozotocin (STZ) by a single intraperitoneal injection or HFD throughout the experiment. The animals were sacrificed on day 1, 8, 15, or 21 of the experiment. Blood, adipose tissue and pancreas were collected and analyzed. In this study, STZ treated animals had a significant (p&lt;0.05) increase in serum glucose and a decrease in insulin, without changes in the size of adipocytes. The levels of both serum glucose and insulin were significantly high in HFD fed animals (p&lt;0.05); being higher in pregnant (p&lt;0.05) than non-pregnant rats. The increase in glucose and insulin levels was associated with increase in the size (hypertrophy) than number (hyperplasia) of adipocytes. The increase in size of adipocytes was higher in viscera (VAT) than subcutaneous (SAT) adipose tissue and related to insulin resistance and GDM development. Histologically, the number of &beta;-cells was decreased and deformed in STZ groups while maintained in HFD groups in both pregnant and non-pregnant animals. The findings of this study show that, intake of HFD during pregnancy may lead to AT expansion and thus insulin resistance, which is one of the risk factors for the hyperglycemia and development of gestational diabetes mellitus. Key words: Pregnancy, insulin-resistance, adipose-tissue, subcutaneous, visceral, streptozotocin.

Predictive liver lipid biomarker signature of Acetyl-coenzyme A carboxylase inhibitor related developmental toxicity in non-pregnant female Han Wistar rats – Lipidomics biomarker discovery and validation

IntroductionAcetyl-coenzyme A carboxylase (ACCase) inhibition is an attractive herbicide target. However, issues with fetal developmental toxicity identified at the late stages of the development process can halt progression of previously promising candidates. ObjectivesTo select and verify predictive lipid biomarkers of ACCase inhibition activity in vivo using liver samples obtained from early stage 7 day repeat dose studies in non-pregnant female Han Wistar rats that could be translated to developmental toxicity endpoints discovered during late-stage studies to provide an early screening tool. MethodsLiver samples from eight rat repeat dose studies, exposed to six ACCase inhibitors from three different chemistries and one alternative mode of action (MoA) that also perturbs lipid biochemistry, were analysed using liquid chromatography – high resolution accurate mass – mass spectrometry. Multivariate and univariate data analysis methods were used for biomarker discovery and validation. ResultsA biomarker signature consisting of sixteen lipids biomarkers were selected. Verification of the signature as indicative of ACCase inhibition was established by demonstrating consistent perturbations in the biomarkers using two different ACCase inhibitor chemistries and the lack thereof with an alternate MoA. The fold change profile pattern was predictive of which test substance doses would or would not cause developmental toxicity. ConclusionA strategy for selecting and verifying a robust signature of lipid biomarkers for predicting a toxicological end point has been described and demonstrated. Differences in lipidomic profiles correlated with developmental toxicity suggesting that indicators of a molecular initiation event resulting in pup developmental toxicity can be predicted from short term, toxicity studies conducted in non-pregnant adult female Han Wistar rats.

Modulatory Activity of Aju Mbaise Polyherbal Formulation on Serum Proinflammatory Cytokines and Prostaglandin Levels in Nulliparous and Parturient Female Albino Rats

Aju Mbaise (Ajumbise), which traces its origin to the people of Mbaise in the Owerri Senatorial District of Imo State in Nigeria, is a composite mixture of approximately eight herbal plants in the forms of herbs, barks, and roots, used for the management of delivery pains, postpartum associated disorders and facilitate recoil of the uterus after delivery. In this study, the modulatory effects of different solvent extracts of the polyherbal on inflammatory markers were investigated in parturient and non-pregnant rats. The rats which were assigned to ten groups of 5 rats each (with controls) were treated such that each group was administered a specific solvent extract (500 mg/kg body weight) while the control groups received normal saline. Treatment lasted 28 days before animals were sacrificed for sample collection and analyses of pro-inflammatory markers. Results of the lethal dose (LD50) assessment of the extracts revealed values &gt;5000 mg/kg body weight for all four extracts. The serum concentrations of interleukin-1b, interleukin-6 and prostaglandin E2 were significantly reduced in the treated nulliparous and parturient rats for all extracts when compared with their respective control values (p&lt;0.05), but that of prostaglandin E1 increased across the test groups when compared with their controls (p&lt;0.05). Therefore, ethanol, chloroform, diethyl ether and aqueous extracts of Ajumbise polyherbal formulation may be safe modulatory agents for the management of pain and inflammatory disorders usually associated with elevated inflammatory cytokines levels and may be used as such, especially in females.

Differential expression of desmin in the uterine myometrium and cervix as a possible mechanism for successful parturition in rats.

Expression of desmin, an intermediate filament, in the myometrium and cervix were investigated in peripartum rats (full term day 22 of pregnancy (DP22)). Des mRNA was expressed in lesser amounts in the cervix at peripartum (DP17 and 21, and day of birth 1 (DB1)), compared to those in the cervixes of ovariectomized rats. Immunohistochemical analysis revealed that desmin protein was diffusely present in the myometrium, and locally in the epithelium of the cervix. Western blot analysis showed that desmin protein levels in the myometrium increased 4- to 6-fold at DP17, 21 and DB1, and decreased rapidly at DB2 to the basal level observed in ovariectomized or non-pregnant rats. In contrast, cervical desmin protein levels increased approximately 10-fold at DP21 compared to those in ovariectomized rats, but decreased rapidly at DB1, indicating its decrease at parturition and an inconsistency between mRNA and protein expression. The administration of 17β-estradiol to ovariectomized rats increased desmin protein levels in the myometrium and cervix after 24h. S-nitrosylated desmin protein was detected in the myometrium and cervix at DP21. The mRNA expression of inducible nitric oxide synthase was consistent with the expression of desmin protein. Thus, desmin, which is regulated by estradiol, is differentially expressed in the myometrium and cervix at peripartum possibly for successful pregnancy and parturition. In the cervix, desmin protein expression seems to be regulated by estradiol at the translational level. S-nitrosylation of desmin may have a potential role in the peripartum uterus.

Ameliorative effect of sesame oil on experimentally induced polycystic ovary syndrome: A cross-link between XBP-1/PPAR-1, regulatory proteins for lipogenesis/steroids.

Polycystic ovary syndrome (PCOS) is a mixed endocrine/metabolic/reproductive disorder in women of reproductive age. Sesame oil (SO) contains sesame lignans & vitamin E with broad-spectrum antioxidant and anti-inflammatory effects. This study investigates the ameliorative effect of SO on experimentally induced PCOS and elucidates the possible molecular mechanisms with a deeper focus on the different signaling pathways involved. The study was carried out on 28 nonpregnant female Wister albino rats that were divided into four equal groups; Group I (control group) received oral 0.5% wt/vol carboxymethyl cellulose daily. Group II (SO group): orally administered SO (2 mL/kg body wt./day) for 21 days. Group III (PCOS group) received letrozole daily, 1 mg/kg, for 21 days. Group IV (PCOS + SO group): concomitantly administered letrozole and SO for 21 days. The serum hormonal and metabolic panel and the homogenate ATF-1, StAR, MAPK, PKA, and PI3K levels of the ovarian tissue were calorimetrically evaluated. However, endoplasmic reticulum (ER) stress was evaluated by ovarian XBP1 and PPAR-γ messenger RNA expression level using the qRT-PCR technique. Ovarian COX-2 was detected immunohistochemically. The results suggest that SO-treated PCOS rats showed a significantly improved hormonal, metabolic panel, inflammatory, and ER stress status with concomitant decreases in ATF-1, StAR, MAPK, PKA, and PI3K in ovarian rats compared to the correspondent values in PCOS without treatment. CONCLUSIONS: The protective effects of SO against PCOS are triggered by ameliorating regulatory proteins of ER stress, lipogenesis, and steroidogenesis through the PI3K/PKA and MAPK/ERK2 signaling cascades. SIGNIFICANCE STATEMENT: Polycystic ovary syndrome (PCOS) is the most common mixed endocrine-metabolic dysfunction among women within the reproductive period, with an estimated prevalence of 5%-26% worldwide. Doctors traditionally recommend metformin for PCOS patients. However, metformin is known to be associated with significant adverse effects and contraindications. This work aimed at shedding light on the ameliorative effect of sesame oil (SO), natural polyunsaturated fatty acids-rich oil, on the induced PCOS model. SO proved to have a marvelous effect on the metabolic and endocrine derangements in the PCOS rat model. We hoped to provide a valuable alternative treatment for PCOS patients to avoid the side effects of metformin and to help PCOS patients for whom metformin is contraindicated.