Protective Effects of Aspirin Supplemented With Quercetin in L-NAME-Induced Preeclampsia-Like Rats.

Aspirin supplemented with quercetin was reported to enhance the therapeutic effects of aspirin in a rat model of preeclampsia. In this study, the underlying mechanisms were further explored. Preeclampsia was induced by L-NAME (50 mg/kg/day) via oral gavage from gestation day (GD)14 to GD19. Aspirin (1.5 mg/kg/day) administration was performed using aspirin mixed with rodent dough from GD0 to GD19. The administration of quercetin (2 mg/kg/day) was performed by intraperitoneal infusion from GD0 to GD19. Protein levels were evaluated using ELISA or Western blot, and microRNA (miRNA) level was evaluated by RT-PCR. Aspirin supplemented with quercetin ameliorated the increase of systolic blood pressure (SBP), proteinuria, tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels, and improved the pregnancy outcomes in preeclampsia rats. Aspirin supplemented with quercetin inhibited miR-155 expression in preeclampsia rats. The decreased miR-155 level in placenta further increased the protein level of SOCS1 and inhibited the phosphorylation of p65. In this study, we demonstrated that aspirin supplemented with quercetin enhanced the effects of aspirin for the treatment of preeclampsia.

Vitamin D regulates microflora and ameliorates LPS-induced placental inflammation in rats.

Preeclampsia is a pregnancy-specific disease, which has become an essential cause of perinatal and neonatal death. Gut microflora becomes the regulator of host immunity through the metabolic pathway. Epidemiological studies provide convincing evidence that vitamin D supplementation can prevent the onset of preeclampsia. However, research on the microbial mechanisms and effective treatment strategies for placental inflammation induced by lipopolysaccharide is lacking. In this study, pregnant rats were induced by LPS to establish a rat model of preeclampsia. Sixteen-sequence analysis was used to determine the composition of microflora in feces. In addition, the protective effect of vitamin D supplementation on LPS-preeclampsia rats was evaluated. The results showed that the blood pressure and creatinine of pregnant rats in the LPS group were significantly higher than those in the control group. In addition, LPS disturbed the intestinal microbial community and reduced microbial diversity. Vitamin D supplementation improves the symptoms of preeclampsia, increases the abundance of intestinal beneficial flora, normalizes the level of inflammatory factors LPS-induced by inhibiting the TLR4/MYD88/NF-κB pathway, and effectively resists the disturbance of uterine spiral artery remodeling induced by LPS. This study established that vitamin D-mediated microbial mechanisms and their inhibition are potential therapeutic targets for the treatment of preeclampsia.

Quercetin Supplement to Aspirin Attenuates Lipopolysaccharide-Induced Pre-eclampsia-Like Impairments in Rats Through the NLRP3 Inflammasome.

BACKGROUND AND OBJECTIVES: Aspirin is a common drug for the treatment of pre-eclampsia. We aimed to explore whether quercetin as a supplement to aspirin could enhance the therapeutic outcome in pre-eclampsia rat models. We further aimed to evaluate the nucleotide-binding oligomerization domain-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome as a potential pre-eclampsia-related molecular mechanism, which can be affected by quercetin treatment. METHODS: Rat pre-eclampsia models were established using an intravenous lipopolysaccharide injection after gestation. Rats were treated with aspirin and quercetin at 6-18 days after pregnancy. On day 20, blood, fetus, and placenta were harvested. Blood pressure and the level of proteinuria were measured every 4 days. Fetal outcomes were analyzed by pup body weight. Serum soluble Fms-like tyrosine kinase-1, PIGF, interleukin-6, and interleukin-10 levels were measured using the enzyme-linked immunosorbent assay. Caspase-1, NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain, and p-caspase-1 levels in the placenta were assessed using western blot or quantitative real-time polymerase chain reaction analyses. RESULTS: Pre-eclampsia rat models showed a pronounced increase in systolic blood pressure and proteinuria after 4 days of pregnancy, while aspirin, quercetin, and aspirin/quercetin combinatory treatment significantly attenuated the blood pressure and proteinuria abnormalities. Notably, the aspirin/quercetin combinatory treatment showed the highest efficacy in attenuating pre-eclampsia-like symptoms. Placental caspase-1 and NLRP3 levels also showed the greatest attenuation in pre-eclampsia rats after aspirin/quercetin treatment. CONCLUSIONS: Our data suggested that quercetin supplementation to aspirin is more effective in attenuating symptoms of pre-eclampsia and improving pregnancy outcomes compared with quercetin or aspirin alone. Quercetin can ameliorate placental NLRP3 inflammasome activation, which might serve as an underlying mechanism for its therapeutic efficacies in pre-eclampsia.

Cadmium-induced preeclampsia-like phenotype in the rat is related to decreased progesterone synthesis in the placenta.

Cadmium (Cd) is a toxic element, which is associated with preeclampsia (PE).We treated pregnant rats with cadmium chloride from gestational days (GDs) 9-12 to introduce the PE-like animal model. Maternal systolic blood pressures (SBPs) and body weights were measured on GDs 0, 5, 10, 15, and 20. Foetuses were delivered by Caesarean section on GD20. Then, the dams were sacrificed and the specimens were obtained. The morphological analysis of the placentae was carried out by haematoxylin and eosin staining examination and immunohistochemistry assay.Our study showed that Cd-treated rats developed PE-like phenotypes, such as hypertension, albuminuria, and foetal growth restriction. Moreover, Cd-injected rats displayed abnormal placental angiogenesis and lower progesterone (P4) levels. We further demonstrated that Cd also inhibited the mRNA and protein expressions of steroidogenic acute regulatory protein, cytochrome P450 cholesterol side-chain cleavage enzyme (CYP11A1), and 3ß-hydroxysteroid dehydrogenase 1 (3ß-HSD1), which are involved in P4 synthesis in the rat placenta.Our study demonstrates that maternal Cd exposure disrupts the local synthesis of P4 in the placenta, which contributes to the onset of PE in pregnant rats. Supplementing P4 at the early gestational stage may be a promising therapeutic strategy to prevent PE, which requires further investigation.

Differential effects of cyclo-oxygenase 1 and 2 inhibition on angiogenesis inhibitor-induced hypertension and kidney damage.

Vascular endothelial growth factor antagonism with angiogenesis inhibitors in cancer patients induces a 'preeclampsia-like' syndrome including hypertension, proteinuria and elevated endothelin (ET)-1. Cyclo-oxygenase (COX) inhibition with aspirin is known to prevent the onset of preeclampsia in high-risk patients. In the present study, we hypothesised that treatment with aspirin would prevent the development of angiogenesis inhibitor-induced hypertension and kidney damage. Our aims were to compare the effects of low-dose (COX-1 inhibition) and high-dose (dual COX-1 and COX-2 inhibition) aspirin on blood pressure, vascular function, oxidative stress, ET-1 and prostanoid levels and kidney damage during angiogenesis-inhibitor therapy in rodents. To this end, Wistar Kyoto rats were treated with vehicle, angiogenesis inhibitor (sunitinib) alone or in combination with low- or high-dose aspirin for 8 days (n=5-7/group). Our results demonstrated that prostacyclin (PGI2) and ET-1 were increased during angiogenesis-inhibitor therapy, while thromboxane (TXA2) was unchanged. Both low- and high-dose aspirin blunted angiogenesis inhibitor-induced hypertension and vascular superoxide production to a similar extent, whereas only high-dose aspirin prevented albuminuria. While circulating TXA2 and prostaglandin F2α levels were reduced by both low- and high-dose aspirin, circulating and urinary levels PGI2 were only reduced by high-dose aspirin. Lastly, treatment with aspirin did not significantly affect ET-1 or vascular function. Collectively our findings suggest that prostanoids contribute to the development of angiogenesis inhibitor-induced hypertension and renal damage and that targeting the prostanoid pathway could be an effective strategy to mitigate the unwanted cardiovascular and renal toxicities associated with angiogenesis inhibitors.

Anti-inflammatory and Antioxidant Effects of Pyrroloquinoline Quinone in L-NAME-Induced Preeclampsia-Like Rat Model.

Preeclampsia (PE) is a pregnancy complication commonly characterized by high blood pressure. Although it is generally believed that the placenta is the root cause of PE, the exact pathogenesis is unknown; consequently, there is no standard clinical treatment. Therefore, it is necessary to explore new therapeutic drugs. Several studies have reported that pyrroloquinoline quinone (PQQ) exhibits anti-inflammatory and antioxidative effects. The purpose of this study was to investigate the protective effect of PQQ diet supplementation on PE-like rat models. L-NAME induced PE-like model rats were intraperitonially administrated with PQQ. The results showed that PQQ significantly improved clinical manifestations and pregnancy outcomes of PE-like rats. The levels of related inflammatory and antioxidant markers were also significantly reversed. A mechanism study showed that PQQ may achieve the above therapeutic effects by inhibiting NF-κB and promoting Nrf2 antioxidant pathways. In conclusion, we showed the protective effect of PQQ on PE-like model rats, by improving anti-inflammation and antioxidation effect through the NF-κB-Nrf2 pathway.

Maternal vitamin D deficiency reduces docosahexaenoic acid, placental growth factor and peroxisome proliferator activated receptor gamma levels in the pup brain in a rat model of preeclampsia.

BACKGROUND: Preeclampsia is a pregnancy disorder characterized with abnormal placental angiogenesis. Vitamin D and long chain polyunsaturated fatty acids (LCPUFA) play a crucial role in pregnancy and are required for normal placental and fetal growth and development. This study reports the effect of maternal vitamin D on LCPUFA levels in the mother and offspring brain fatty acid levels and angiogenic markers in a rat model of preeclampsia. METHODS: Female rats were divided into four groups from pre-pregnancy to pregnancy, viz Control; Preeclampsia (PE); Vitamin D deficient with PE (VDD-PE) and Vitamin D supplemented with PE (VDS-PE). Preeclampsia was induced by administering l-nitroarginine methyl ester (L-NAME) at the dose of 50 mg/kg body weight/day from day 14 to day 19 of gestation. Dams were sacrificed at d20 of gestation to collect dam blood, placenta and pup brain. LCPUFA levels from dam plasma, erythrocytes and placenta and its transcription factor peroxisome proliferator activated receptor gamma (PPAR-g) from placenta were estimated. Pup brain LCPUFA levels, angiogenic factors vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) and transcription factor hypoxia inducible factor (Hif-1α) and PPAR-g were also estimated. RESULTS: Maternal vitamin D status influences fatty acid levels. Placental PPAR-g levels were lower in the VDD-PE group as compared to the VDS-PE groups (p < 0.01). In the offspring brain, both PE and VDD-PE group showed lower levels of DHA (p < 0.05 for both) while saturated fatty acids (SFA) levels in the VDD-PE group were higher as compared to the control group (p < 0.05). VDD-PE group also showed lower levels of PlGF and PPAR-g (p < 0.01 and p < 0.05, respectively) in the pup brain while vitamin D supplementation demonstrated levels similar to control. CONCLUSION: This study for the first time demonstrates that maternal vitamin D status influences LCPUFA metabolism and angiogenesis in the offspring brain.

Effect and mechanism of prophylactic use of tadalafil during pregnancy on l-NAME-induced preeclampsia-like rats.

INTRODUCTION: Preeclampsia (PE) is a serious maternal inflammatory disease with endothelial cell dysfunction, and there is a lack of effective treatment and prevention. Tadalafil is considered to be a promising drug for PE. This study aimed to determine whether and how tadalafil use during early pregnancy alleviates PE induced by N-nitro-l-arginine-methyl-ester (l-NAME), an antagonist of nitric oxide synthase, in rats. METHODS: Twenty-eight Sprague-Dawley (SD) rats were randomly divided into 4 equal groups on gestational day 0 (GD0): a pregnant control group, an l-NAME-treated PE group and two prophylactic low-dose and high-dose tadalafil groups. Blood pressure was measured on GD0, 5, 10, 15 and 20. Proteinuria was assessed on GD0 and 18. Femoral artery ultrasound was performed on GD19. Tissue sampling was performed on GD20. The perinatal outcomes, placenta and kidney tissue morphology, and endothelial and inflammatory markers were examined. RESULTS: Prophylactic administration of low and high doses of tadalafil improved l-NAME induced hypertension, proteinuria, maternal weight loss during pregnancy, fetal growth restriction and flow-mediated dilatation, balanced endothelial-relative factors, and alleviated inflammation activation in placenta and kidney tissue. What's more, in some results, the HT group performed better than the LT group. DISCUSSION: Our results indicate that prophylactic use of tadalafil in l-NAME-induced PE-like rat models alleviates PE symptoms, promotes fetal growth, protects endothelial function and reduces inflammation, suggesting that tadalafil may be a potential drug for the prevention of PE.

Folic Acid Supplement Use and Increased Risk of Gestational Hypertension.

Current results regarding the effect of folic acid (FA) supplement use on gestational hypertension (GH) and preeclampsia are limited and inconsistent. We aimed to investigate whether FA supplement use was associated with GH and preeclampsia. Participants from the Tongji Maternal and Child Health Cohort with information on periconceptional FA supplement use and diagnosis of GH/preeclampsia were included (n=4853). Robust Poisson regression was used to assess the association of FA supplement use and GH and preeclampsia. Among the 4853 participants in this study, 1161 (23.9%) and 161 (3.3%) women were diagnosed with GH and preeclampsia, respectively. The risk ratio of developing GH was higher in women who used ≥800 µg/d FA supplement from prepregnancy through midpregnancy than nonusers (risk ratio, 1.33 [1.08-1.65]). After adjusting for social-demographic, reproductive, lifestyle factors, family history of hypertension, other supplement use, and gestational weight gain, the adverse association remained significant (risk ratio, 1.32 [1.06-1.64]). Restricting the analysis among women with normal weight, without family history of hypertension, and without gestational diabetes mellitus, the positive FA-GH association still existed. We did not find any significant association between FA supplement use and preeclampsia regardless of adjustment. High-dose (≥800 µg/d) FA supplement use from prepregnancy through midpregnancy was associated with increased risk of GH. Attention should be given to avoid the potential risk of GH due to inappropriate FA supplement use in women who are planning or capable of pregnancy.

Vitexin ameliorates preeclampsia phenotypes by inhibiting TFPI-2 and HIF-1α/VEGF in a l-NAME induced rat model.

Preeclampsia (PE) is a leading cause of maternal and perinatal morbidity and mortality with few safe, effective, and minimally invasive therapeutics. Inflammation, oxidative stress, and angiogenic imbalance have been reported to contribute to PE pathogenesis. Vitexin (VI) possesses various pharmacological activities including the potent regulation of the above biological processes in different conditions. This study aims to investigate whether VI has therapeutic potential to PE and the underlying mechanisms. Sprague-Dawley pregnant rats pretreated with or without VI were fed with l-NAME-containing water to induce experimental PE. Results showed that VI decreased high systolic blood pressure and urinary protein in PE rats time- and dose-dependently. Meanwhile, VI of higher dosage (45, 60 mg/kg) corrected abnormal pregnancy outcomes, including low pup weight and low pups/placenta ratio. In addition, VI of high dosage (60 mg/kg) decreased sFlt-1, increased PlGF and alleviated oxidative stress both in blood and placental samples compared with nontreated PE group. Furthermore, VI alleviated placental TFPI-2, HIF 1α, and VEGF in PE rats. In short, the present study suggests that the inhibition of placental TFPI-2 and HIF-1α/VEGF might be one of the potential mechanisms underlying the protective effects of VI to experimental PE induced by l-NAME.

Evaluation of the effects of Uncaria rhynchophylla alkaloid extract on LPS-induced preeclampsia symptoms and inflammation in a pregnant rat model.

Excessive pro-inflammatory cytokines result in adverse pregnancy outcomes, including preeclampsia-like phenotypes, and fetal growth restriction. Anti-inflammation might be an effective therapy. The aim of this research was to investigate whether Uncaria rhynchophylla alkaloid extract (URE), a highly safe anti-inflammation constituent of the herb, can inhibit inflammation and improve clinical characteristics of preeclampsia in a lipopolysaccharide (LPS)-induced preeclampsia rat model. The rat model was established by daily administration of LPS (1 µg/kg body weight per day) from gestational day (GD) 14 to 19. Different doses of URE (35, 70, and 140 mg/kg body weight per day) were administered from GD 14 to GD 19. The effects of URE on proteinuria, maternal hypertension, pregnancy outcomes, as well as pro-inflammatory cytokines levels in serum and placenta were measured. High-dose URE (HURE) treatment decreased LPS-induced mean 24-h proteinuria and systolic blood pressure, and increased fetal weight, placental weight, and the number of live pups (P<0.05). Moreover, increased serum and placental levels of interleukin (IL)-6, IL-1ß, tumor necrosis factor-α, and interferon-γ in the LPS-treated group were obviously inhibited after HURE administration (P<0.01). URE improved preeclampsia symptoms and mitigated inflammatory responses in the LPS-induced preeclampsia rat model, which suggests that the anti-inflammation effect of URE might be an alternative therapy for preeclampsia.

Ameliorative effects of pre-eclampsia by quercetin supplement to aspirin in a rat model induced by L-NAME.

As an inflammatory disease, pre-eclampsia is correlated with elevation of pro-inflammatory cytokines and maternal endothelial dysfunction. Aspirin plays an important role in the prevention and therapy of pre-eclampsia. Quercetin is a bioflavonoid which has anti-oxidant and reno-protective abilities. We aimed to figure out the effects of quercetin supplement to aspirin on the therapy against pre-eclampsia. Female pregnant Sprague-Dawley rats were divided into five groups according to the drug treatment. Aspirin [1.5 mg/kg body weight (BW)] or quercetin (2 mg/kg BW) treatment was administered from gestational day (GD) 4 to GD19. Rat model of pre-eclampsia was induced by NG-nitro-Larginine-methyl-ester (L-NAME). In pre-eclampsia rats induced by L-NAME, systolic blood pressures (SBP), proteinuria, malonyldialdehyde (MDA), and inflammatory cytokines levels were decreased by the treatment of quercetin supplement to aspirin. In the uterus, quercetin supplement to aspirin prevented the expression of VEGF and sFlt-1 mRNA. The treatment of quercetin supplement to aspirin rescued the declined survival rate and weight of pups caused by L-NAME-induced pre-eclampsia. Based on our study, compared with the treatment of aspirin alone, quercetin supplement to aspirin enhanced the therapeutic effects of aspirin on pre-eclampsia rats induced by L-NAME.

Evaluation of the effects of Uncaria rhynchophylla alkaloid extract on LPS-induced preeclampsia symptoms and inflammation in a pregnant rat model

Excessive pro-inflammatory cytokines result in adverse pregnancy outcomes, including preeclampsia-like phenotypes, and fetal growth restriction. Anti-inflammation might be an effective therapy. The aim of this research was to investigate whether Uncaria rhynchophylla alkaloid extract (URE), a highly safe anti-inflammation constituent of the herb, can inhibit inflammation and improve clinical characteristics of preeclampsia in a lipopolysaccharide (LPS)-induced preeclampsia rat model. The rat model was established by daily administration of LPS (1 μg/kg body weight per day) from gestational day (GD) 14 to 19. Different doses of URE (35, 70, and 140 mg/kg body weight per day) were administered from GD 14 to GD 19. The effects of URE on proteinuria, maternal hypertension, pregnancy outcomes, as well as pro-inflammatory cytokines levels in serum and placenta were measured. High-dose URE (HURE) treatment decreased LPS-induced mean 24-h proteinuria and systolic blood pressure, and increased fetal weight, placental weight, and the number of live pups (P<0.05). Moreover, increased serum and placental levels of interleukin (IL)-6, IL-1β, tumor necrosis factor-α, and interferon-γ in the LPS-treated group were obviously inhibited after HURE administration (P<0.01). URE improved preeclampsia symptoms and mitigated inflammatory responses in the LPS-induced preeclampsia rat model, which suggests that the anti-inflammation effect of URE might be an alternative therapy for preeclampsia.

Curcumin improves LPS-induced preeclampsia-like phenotype in rat by inhibiting the TLR4 signaling pathway.

INTRODUCTION: Abnormal inflammation mediated by Toll-like receptor 4 (TLR4) signaling pathway contributes to preeclampsia (PE). Because curcumin can inhibit TLR4 signaling pathway, we investigated its effects on a PE rat model. METHODS: Twenty-one pregnant rats were randomly divided into three groups: 1) seven rats were injected 0.5 µg/kg lipopolysaccharide (LPS) on gestational day (GD) 5 to create a PE model (LPS-treated group), 2) seven rats were injected with a similar dosage of LPS and further treated with curcumin (0.36 mg/kg) (LPS-curcumin-treated group), 3) seven rats received saline (control group). Blood pressure and urinary protein level were observed. Immunostaining and periodic acid-Schiff staining of placenta were conducted. TLR4 and downstream Nuclear Factor-κB (NF-κB) expressions of placenta were analyzed by Western blot and immunohistochemistry. IL-6 and MCP-1 in rat serum and placenta were determined by ELISA and qRT-PCR. RESULTS: Compared to LPS-treated group, LPS-curcumin-treated group had decreased blood pressure and urinary protein level, similar to control group. Furthermore, deficient trophoblast invasion and spiral artery remodeling induced by LPS were improved by curcumin. Increased TLR4, NF-κB and IL-6, MCP-1 protein expressions in LPS-treated group were significantly decreased after curcumin administration. DISCUSSION: Curcumin improves the PE-like phenotype in rat model by reducing abnormal inflammation related to TLR4 signaling pathway.

Placental Cadmium Levels Are Associated with Increased Preeclampsia Risk.

Environmental exposure to heavy metals is a potentially modifiable risk factor for preeclampsia (PE). Toxicologically, there are known interactions between the toxic metal cadmium (Cd) and essential metals such as selenium (Se) and zinc (Zn), as these metals can protect against the toxicity of Cd. As they relate to preeclampsia, the interaction between Cd and these essential metals is unknown. The aims of the present study were to measure placental levels of Cd, Se, and Zn in a cohort of 172 pregnant women from across the southeast US and to examine associations of metals levels with the odds of PE in a nested case-control design. Logistic regressions were performed to assess odds ratios (OR) for PE with exposure to Cd controlling for confounders, as well as interactive models with Se or Zn. The mean placental Cd level was 3.6 ng/g, ranging from 0.52 to 14.5 ng/g. There was an increased odds ratio for PE in relationship to placental levels of Cd (OR = 1.5; 95% CI: 1.1-2.2). The Cd-associated OR for PE increased when analyzed in relationship to lower placental Se levels (OR = 2.0; 95% CI: 1.1-3.5) and decreased with higher placental Se levels (OR = 0.98; 95% CI: 0.5-1.9). Similarly, under conditions of lower placental Zn, the Cd-associated OR for PE was elevated (OR = 1.8; 95% CI: 0.8-3.9), whereas with higher placental Zn it was reduced (OR = 1.3; 95% CI: 0.8-2.0). Data from this pilot study suggest that essential metals may play an important role in reducing the odds of Cd-associated preeclampsia and that replication in a larger cohort is warranted.

A1M Ameliorates Preeclampsia-Like Symptoms in Placenta and Kidney Induced by Cell-Free Fetal Hemoglobin in Rabbit.

Preeclampsia is one of the most serious pregnancy-related diseases and clinically manifests as hypertension and proteinuria after 20 gestational weeks. The worldwide prevalence is 3-8% of pregnancies, making it the most common cause of maternal and fetal morbidity and mortality. Preeclampsia lacks an effective therapy, and the only "cure" is delivery. We have previously shown that increased synthesis and accumulation of cell-free fetal hemoglobin (HbF) in the placenta is important in the pathophysiology of preeclampsia. Extracellular hemoglobin (Hb) and its metabolites induce oxidative stress, which may lead to acute renal failure and vascular dysfunction seen in preeclampsia. The human endogenous protein, α1-microglobulin (A1M), removes cell-free heme-groups and induces natural tissue repair mechanisms. Exogenously administered A1M has been shown to alleviate the effects of Hb-induced oxidative stress in rat kidneys. Here we attempted to establish an animal model mimicking the human symptoms at stage two of preeclampsia by administering species-specific cell-free HbF starting mid-gestation until term, and evaluated the therapeutic effect of A1M on the induced symptoms. Female pregnant rabbits received HbF infusions i.v. with or without A1M every second day from gestational day 20. The HbF-infused animals developed proteinuria and a significantly increased glomerular sieving coefficient in kidney that was ameliorated by co-administration of A1M. Transmission electron microscopy analysis of kidney and placenta showed both intracellular and extracellular tissue damages after HbF-treatment, while A1M co-administration resulted in a significant reduction of the structural and cellular changes. Neither of the HbF-treated animals displayed any changes in blood pressure during pregnancy. In conclusion, infusion of cell-free HbF in the pregnant rabbits induced tissue damage and organ failure similar to those seen in preeclampsia, and was restored by co-administration of A1M. This study provides preclinical evidence supporting further examination of A1M as a potential new therapy for preeclampsia.

The effect of Kraussianone-2 (Kr2), a natural pyrano-isoflavone from Eriosema kraussianum, in an L-NAME- induced pre-eclamptic rat model.

This study aimed to investigate the effects of Kraussianone-2 (Kr2), a pyrano-isoflavone isolated from the roots of Eriosema kraussianum N. E. Br. (Fabaceae) on various fetal and physiological parameters in pregnant, L-NAME treated Sprague-Dawley rats. Twenty-four pregnant Sprague-Dawley dams were divided into three groups (n = 8), i.e. the control group (CON), the experimental control group (PRE), where the pre-eclampsia-like symptoms were induced using L-NAME, and the experimental group (EK2), where the pre-eclampsia-like symptoms were once again induced using L-NAME, however, these animals were treated with Kr2. On gestation day 20 the animals were sacrificed, at which time a laparotomy was performed and the number of live pups were counted and their corresponding birth and placental weights were recorded. Blood was also collected in heparin-coated tubes and the plasma samples were then analysed for specific variables using commercially available kits for rats. Kraussianone-2 administration decreased fetal mortality and demonstrated a trend toward increasing birth and placental weights in this model. Furthermore, Kr2 administration also reduced blood pressure amplification and decreased the plasma concentrations of two antiangiogenic factors, soluble fms-like tyrosine kinase1 (sFlt-1) and soluble endoglin (sEng). We speculate that Kr2, by improving uterine artery blood flow, results in improved fetal outcomes and decreased antiangiogenic factors in pregnant, L-NAME treated, Sprague-Dawley rats.

[Protective effects and its mechanism on neural cells after folic acid intervention in preeclampsia rat model].

OBJECTIVE: To investigate protective effects and mechanism of folic acid on brain neural cells in preeclampsia rat model. METHODS: Adult pregnant Wistar rats were randomly divided into 4 groups (n = 10 in each group). Rats in model group were injected intraperitoneally with homocysteine (Hcy, 200 mg × kg(-1) × d(-1)) daily and were injected subcutaneously every other day with monosodium glutamate (MSG, 1 g × kg(-1)· 48 h(-1)) from the 10th day of pregnancy to establish the model of preeclampsia. Low-dose folic acid (low dose group 10 mg × kg(-1) × d(-1)) and high-dose folic acid (high dose group 20 mg × kg(-1) × d(-1)) were given intragastric administration with folic acid tablets dissolved in saline daily at the same time of establishing model. Rats in control group were injected or intragastric administration with the same dose of saline as above up to the 20th day of pregnancy. Brain tissue was fixed on the 20th day of pregnancy, so was that plasma folic acid was measured with automatic electro-chemiluminescence. Rats' neural nerve cells apoptosis was observed with tunel. Nuclear factor (NF)-κB activation was observed with immunohistochemical staining. bcl-2 mRNA and protein expression changes were observed by using reverse transcription (RT)-PCR and western blot. RESULTS: (1) Plasma folate concentrations were (39.5 ± 3.4) nmol/L in low dose group and (40.1 ± 5.4) nmol/L in high dose group, which were all significantly higher than (26.9 ± 6.7) nmol/L in model group (P < 0.01). Plasma folate in low dose and high dose group did not show significant difference (P > 0.05); (2) Apoptosis cell were 48.2 ± 9.1 in low dose group and 44.7 ± 8.3 in high dose group, which were significantly lower than 75.8 ± 10.1 in model group (P < 0.01). However, apoptosis cell in low dose and high dose group did not show significant difference (P > 0.05); (3) NF-κB activation were 48 ± 9 in low dose group and 45 ± 8 in high dose group, which were significantly lower 76 ± 10 in model group (P < 0.01). NF-κB activation in low dose and high dose group did not show significant difference (P > 0.05); (4) bcl-2 mRNA and protein expression were 0.98 ± 0.49 and 0.89 ± 0.52 in low dose group and 0.95 ± 0.38 and 0.92 ± 0.47 in high dose group which was significantly higher than 0.62 ± 0.20 and 0.45 ± 0.37 in model group (P < 0.01); bcl-2 expression in low dose and high dose group showed no significant difference (P > 0.05). CONCLUSIONS: Folic acid has a protective role on neural cells in preeclampsia model rats. The anti-apoptosis mechanism may be related with inhibiting NF-κB activation and promoting bcl-2 gene and protein expression.

Effects of Danshensu on maternal syndrome in phosphatidylserine/phosphatidylcholine microvesicle induced-mouse model: is it a candidate for preeclampsia remedy?

BACKGROUND: Up to date, there is few satisfactory pharmacotherapy, except for aspirin and heparin, to stop the preeclampsia progression. Although the mechanism of preeclampsia is poorly understood, it has been proven to be associated with coagulation activation. Researches on prophylactic and therapeutic application of anticoagulants may benefit the clinical aspects of preeclampsia individuals. This study aimed to evaluate the effects of Danshensu on maternal syndrome in phosphatidylserine/phosphatidylcholine (PS/PC) microvesicle induced-mouse model. METHODS: Sixty-six preeclampsia-like pregnant mice, induced by PS/PC microvesicle administration, were randomly divided into six groups. From days 5.5 to 16.5 of pregnancy, each group was respectively treated as follows: a) mice in group C (n = 12, control group) were injected with 100 microl of filtered phosphate-buffered saline into the tail vein every day; b) group PE (n = 15, preeclampsia model group) were injected in the same way with 100 microl of filtered PS/PC vesicle suspension; c) group H (n = 9, group treated with heparin) were injected with 1 unit heparin together with PS/PC vesicle suspension; d) group A (n = 10, group treated with aspirin) were injected with 20 microg/g aspirin-DL lysine as well; e) group LD (n = 10, group treated with low-dose Danshensu) were injected with 10 microg/g Danshensu; and f) group HD (n = 10, group treated with high-dose Danshensu) were injected with 30 microg/g Danshensu. Systolic blood pressure, total urinary protein levels, blood tests for some hemostatic function parameters (mean platelet counts, plasma antithrombin III activity (AT-III), D-D dimmer levels, and thrombin time), fibrin deposition by phosphotungstic acid hematoxylin staining, and thrombomodulin expression by immunohistochemistry staining in placentas were examined as indices for maternal syndrome. RESULTS: Heparin showed significant effects on maternal syndrome of preeclampsia such as hypertension and proteinuria, and different doses of Danshensu also presented the certain effects. High-dose Danshensu and aspirin all demonstrated better effects than low-dose Danshensu on decreasing blood pressure to normal level, while high-dose Danshensu demonstrated better effects than aspirin and low-dose Danshensu on decreasing proteinuria to normal level. As to Danshensu's effects on hemostatic function, high- and low-dose Danshensu's marked effects on increasing the plasma AT-III activity were the same as that of aspirin and inferior to that of heparin. High-dose Danshensu's better effect on elevating the platelet counts was superior to low-dose Danshensu and aspirin. Low-dose Danshensu's obvious effect on decreasing D-D levels was close to heparin and superior to high-dose Danshensu and aspirin. High- and low-dose Danshensu's significant effects on reduced thrombin time level are same to heparin. Different anticoagulants all played improvement roles in placental fibrin depositions, but heparin and high-dose Danshensu's roles on lowering thrombomodulin expression in placentas were superior to low-dose Danshensu and aspirin. However, anticoagulant function of high-dose Danshensu was still inferior to heparin. We found long-term use of heparin and aspirin, in spite of low-dose administration, could raise the risk of bleeding such as placental abruption and intestinal hemorrhage. But no any side effect was observed in mice treated with different doses of Danshensu in our study. CONCLUSIONS: Danshensu has proven to be effective and safe in ameliorating the prognosis of maternal syndrome in a preeclampsia mouse model. We suggest long-term provision of low-dose Danshensu in pregnancy, leading to an improvement of preeclampsia syndrome with considerable maternal safety.

Maternal exposure to folic acid antagonists and placenta-mediated adverse pregnancy outcomes.

BACKGROUND: In previous studies, maternal exposure to folic acid antagonists was associated with increased risks of neural tube defects, cardiovascular defects, oral clefts and urinary tract defects. The objective of the current study was to assess the possible effects of using folic acid antagonists in pregnancy on placenta-mediated adverse outcomes of pregnancy. METHODS: We used data from an administrative database to retrospectively compare the occurrence of placenta-mediated adverse pregnancy outcomes between pregnant women exposed to folic acid antagonists and women without exposure to these agents. RESULTS: We included in the analysis a total of 14 982 women who had been exposed to folic acid antagonists and 59 825 women who had not been exposed. Sulfamethoxazole-trimethoprim was the most frequently prescribed dihydrofolate reductase inhibitor (a total of 12 546 exposures during the preconception period and all 3 trimesters), and phenobarbital was the most frequently prescribed among the other folic acid antagonists (a total of 1565 exposures). The risks of preeclampsia (adjusted odds ratio [OR] 1.52, 95% confidence interval [CI] 1.39-1.66), severe preeclampsia (OR 1.77, 95% CI 1.38-2.28), placental abruption (OR 1.32, 95% CI 1.12-1.57), fetal growth restriction defined as less than the 10th percentile (OR 1.07, 95% CI 1.01-1.13), fetal growth restriction defined as less than the 3rd percentile (OR 1.22, 95% CI 1.11-1.34) and fetal death (OR 1.35, 95% CI 1.07-1.70) were greater among mothers with exposure to folic acid antagonists. In general, the risks associated with exposure to other folic acid antagonists were higher than those associated with exposure to dihydrofolate reductase inhibitors. Supplementary analyses involving tight matching with propensity score, restriction of the analysis to women with exposure during the first and second trimesters and restriction of the analysis to specific categories of folic acid antagonists yielded similar results. INTERPRETATION: Maternal exposure to folic acid antagonists appears to increase the risk of placenta-mediated adverse outcomes of pregnancy.