Effect of tocopherol supplementation during last trimester of pregnancy on mRNA abundances of interleukins and angiogenesis in ovine placenta and uterus

Deficiency of HtrA4 in BeWo cells downregulates angiogenesis through IL-6/JAK/STAT3 signaling

In a previous study, we investigated the effects of high-temperature requirement factor A4 (HtrA4) deficiency on trophoblasts using the BeWo KO cell line. However, the effects of this deficiency on angiogenesis remain unclear. To explore the role of HtrA4 in angiogenesis, HUVECs were co-cultured with wild-type BeWo cells (BeWo WT), BeWo KO, and HtrA4-rescued BeWo KO (BeWo KO-HtrA4 rescue) cells. Dil staining and dextran analysis revealed that HUVECs co-cultured with BeWo KO formed tubes, but they were often disjointed compared to those co-cultured with BeWo WT, BeWo KO-HtrA4 rescue, and HUVECs controls. RT-PCR, ELISA, and western blot analysis were performed to assess angiogenesis-related factors at the mRNA and protein levels. HtrA4 deficiency inhibited IL-6 expression in trophoblasts, and the reduced secretion of IL-6 decreases VEGFA expression in HUVECs by modulating the JAK2/STAT3 signaling pathway to prevent tube formation. Moreover, rescuing HtrA4 expression restored the HUVEC tube formation ability. Interestingly, IL-6 expression was lower in supernatants with only cultured HUVECs than in co-cultured HUVECs with BeWo WT cells, but the HUVEC tube formation ability was similar. These findings suggest that the promoting angiogenesis-related signaling pathway differs between only HUVECs and co-cultured HUVECs, and that the deficiency of HtrA4 weakens the activation of the IL-6/JAK/STAT3/VEGFA signaling pathway, reducing the ability of tube formation in HUVECs. HtrA4 deficiency in trophoblasts hinders angiogenesis and may contribute to placental dysfunction.

Modelling preeclampsia: a comparative analysis of the common human trophoblast cell lines

Preeclampsia remains a challenge without an effective therapy. Evidence supports targetability of soluble fms‐like tyrosine kinase‐1 (sFlt‐1) and soluble endoglin (sEng), which are released excessively from the placenta under ischemic and hypoxic stresses. We compared four trophoblast cell lines, BeWo, Jar, Jeg‐3, and HTR‐8/SVneo, in order to identify a suitable model for drug screening. Cultured trophoblasts were exposed to 1% oxygen vs. normoxia for 24‐48 hr; human umbilical vein and aortic endothelial cells were included for comparison. Supernatant sFlt‐1 and sEng concentrations were measured by ELISA, and sFlt‐1 mRNA expression determined by RT‐PCR. Cellular responses to experimental therapeutics were explored. All four trophoblast lines secreted sEng, which did not increase by hypoxia. BeWo, Jar, and Jeg‐3 exhibited significantly enhanced expression of sFlt‐1 i13 and e15a mRNA in response to hypoxia; however, only BeWo released a detectable level of sFlt‐1 protein, which was doubled by hypoxia. In contrast, hypoxia decreased sFlt‐1 mRNA expression and protein release in HTR‐8/SVneo, similarly to endothelial cells. The cellular mechanism involved HIFα. BeWo responded to representative agents similarly to human primary placental tissues in the literature. These data support that the BeWo‐hypoxia model mimics a key pathogenic mechanism of preeclampsia and has potential value for translational drug discovery.

The rise, the fall and the renaissance of vitamin E

This review deals with the expectations of vitamin E ability of preventing or curing, as a potent antioxidant, alleged oxidative stress based ailments including cardiovascular disease, cancer, neurodegenerative diseases, cataracts, macular degeneration and more. The results obtained with clinical intervention studies have highly restricted the range of effectiveness of this vitamin. At the same time, new non-antioxidant mechanisms have been proposed. The new functions of vitamin E have been shown to affect cell signal transduction and gene expression, both in vitro and in vivo. Phosphorylation of vitamin E, which takes place in vivo, results in a molecule provided with functions that are in part stronger and in part different from those of the non-phosphorylate compound. The in vivo documented functions of vitamin E preventing the vitamin E deficiency ataxia (AVED), slowing down the progression of non-alcoholic steato-hepatitis (NASH), decreasing inflammation and potentiating the immune response are apparently based on these new molecular mechanisms. It should be stressed however that vitamin E, when present at higher concentrations in the body, should exert antioxidant properties to the extent that its chromanol ring is unprotected or un-esterified.

Subclinical Pregnancy Toxemia-Induced Gene Expression Changes in Ovine Placenta and Uterus

The objective was to elucidate gene expression differences in uterus, caruncle, and cotyledon of ewes with subclinical pregnancy toxemia (SCPT) and healthy ewes, and to identify associated biological functions and pathways involved in pregnancy toxemia. On Day 136 (±1 day) post-breeding, ewes (n = 18) had body condition score (BCS; 1–5; 1, emaciated; 5, obese) assessed, and blood samples were collected for plasma glucose and β-hydroxybutyrate (BHBA) analyses. The ewes were euthanized, and tissue samples were collected from the gravid uterus and placentomes. Based on BCS (2.0 ± 0.02), glucose (2.4 ± 0.33), and BHBA (0.97 ± 0.06) concentrations, ewes (n = 10) were grouped as healthy (n = 5) and subclinical SCPT (n = 5) ewes. The mRNA expressions were determined by quantitative PCR method, and prediction of miRNA partners and target genes for the predicted miRNA were identified using miRDB (http://mirdb.org/miRDB/). Top ranked target genes were used to identify associated biological functions and pathways in response to SPCT using PANTHER. The angiogenesis genes VEGF and PlGF, and AdipoQ, AdipoR2, PPARG, LEP, IGF1, IGF2, IL1b, and TNFα mRNA expressions were lower in abundances, whereas hypoxia genes eNOS, HIF1a, and HIF 2a, and sFlt1 and KDR mRNA expressions were greater in abundances in uterus and placenta of SCPT ewes compared to healthy ewes (P < 0.05). The predicted miRNA and associated target genes contributed to several biological processes, including apoptosis, biological adhesion, biological regulation, cellular component biogenesis, cellular process, developmental process, immune system process, localization, metabolic process, multicellular organismal process, reproduction, and response to stimulus. The target genes were involved in several pathways including angiogenesis, cytoskeletal regulation, hypoxia response via HIF activation, interleukin signaling, ubiquitin proteasome, and VEGF signaling pathway. In conclusion, genes associated with blood vessel remodeling were lower in abundances and that the genes associated with hypoxic conditions were greater in abundances in the uteroplacental compartment of SCPT ewes. It is obvious that the factors that influence placental vascular development and angiogenesis as noted in this study set the course for hemodynamic changes and hence have a major impact on the rate of transplacental nutrient exchange, fetal growth, and health of the dam.

Effect of injectable vitamin E on incidence of retained fetal membranes and reproductive performance of dairy cows

The objectives were to evaluate the effects of injectable vitamin E during the last 3 wk prepartum on the incidence of retained fetal membranes (RFM) and reproductive performance. Dairy cows (n=890), 390 Holsteins (132 nulliparous and 258 parous) and 500 crossbred Holstein × Gyr (199 nulliparous and 301 parous), from 3 dairy farms in Brazil were assigned to the study. In all 3 farms, from October to March, prepartum cows grazed tropical grasses and received 2 kg/d of a mixture of finely ground corn, soybean meal, and minerals and vitamins. From April to September prepartum cows received a total mixed ration composed of corn silage, finely ground corn, soybean meal, and minerals and vitamins. During the prepartum period, cows were fed 280 (farm 1), 390 (farm 2), and 480 IU (farm 3) of supplemental vitamin E per day, and throughout postpartum, cows were fed 370 (farm 1), 500 (farm 2), and 600 (farm 3) IU of supplemental vitamin E. Within each farm, cows were randomly assigned to remain as untreated controls or to receive 3 i.m. injections of 1,000 IU each of dl-α-tocopherol administered at 19.2 ± 4.3, 12.9 ± 3.3, and 6.2 ± 2.9 d before calving (VitE). Blood was sampled from 141 cows immediately before enrollment to determine the α-tocopherol and cholesterol statuses. Blood was also sampled and analyzed for concentrations of cortisol and nonesterified fatty acids in the last 3 wk of gestation. The serum concentration of α-tocopherol or α-tocopherol:cholesterol ratio did not differ between treatments and averaged 2.97 ± 0.10 μg/mL and 4.46 ± 0.16 × 10(-3), respectively. In total, 53.2% of the cows had an inadequate concentration of serum α-tocopherol based on the 3.0 μg/mL cut-off for adequacy. The risk of RFM decreased as serum α-tocopherol increased. Milk production did not differ between controls and VitE cows. Treatment with injectable α-tocopherol decreased RFM from 20.1 to 13.5%, decreased incidence of stillbirth from 14.9 to 6.8%, and tended to decrease death by 200 d postpartum. VitE cows tended to have improved pregnancy per insemination at first AI (36.7 vs. 30.1%) because of decreased pregnancy loss from 31 to 62 d of gestation (12.5 vs. 20.5%). Despite a similar insemination rate, VitE cows had 22% greater pregnancy rate than control cows. Cows receiving vitamin E had decreased circulating cortisol and nonesterified fatty acids around calving. In summary, when cows were fed limited amounts of supplemental vitamin E, 28 to 48% of the recommendations, prepartum supplementation with injectable α-tocopherol decreased incidence of RFM and improved reproduction.

Can proinflammatory cytokine gene expression explain multifidus muscle fiber changes after an intervertebral disc lesion?

STUDY DESIGN

Longitudinal case-controlled animal study.

OBJECTIVE

To investigate the effect of an intervertebral disc (IVD) lesion on the proportion of slow, fast, and intermediate muscle fiber types in the multifidus muscle in sheep, and whether muscle fiber changes were paralleled by local gene expression of the proinflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 1-β.

SUMMARY OF BACKGROUND DATA

Structure and behavior of the multifidus muscle change in acute and chronic back pain, but the mechanisms are surprisingly poorly understood and the link between structure and behavior is tenuous. Although changes in muscle fiber types have the potential to unify the observations, the effect of injury on muscle fiber distribution has not been adequately tested, and understanding of possible mechanisms is limited.

METHODS

The L1-L2, L3-L4, and L5-L6 IVDs of 11 castrated male sheep received anterolateral lesions. Six control sheep underwent no surgical procedures. Multifidus muscle tissue was harvested at L4 for muscle fiber analysis using immunohistochemistry and L2 for cytokine analysis with polymerase chain reaction for local gene expression of TNF-α and interleukin-1β.

RESULTS

The proportion of slow muscle fibers in multifidus was significantly less in the lesioned animals both ipsilateral and contralateral to the IVD lesion. The greatest reduction in slow fibers was in the deep medial muscle region. A greater prevalence of intermediate fibers on the uninjured side implies a delayed fiber-type transformation on that side. TNF-α gene expression in multifidus was greater on both sides in the lesion animals than in the muscle of control animals. Interleukin-1β was increased only on the injured side.

CONCLUSION

These data provide evidence of muscle fiber changes after induction of an IVD lesion and a parallel increase in TNF-α expression. Proinflammatory cytokine changes provide a novel mechanism to explain behavioral and structural changes in multifidus.

LEVEL OF EVIDENCE

N/A.