1.
Association of vitamin D level and vitamin D deficiency with risk of preeclampsia: A systematic review and updated meta-analysis.
Akbari, S, Khodadadi, B, Ahmadi, SAY, Abbaszadeh, S, Shahsavar, F
Taiwanese journal of obstetrics & gynecology. 2018;(2):241-247
Abstract
OBJECTIVES Because of the immune modulatory effects of vitamin D3 in preeclampsia, we intend to have a systematic review and meta-analysis on association of both 25-hydroxy vitamin D (25-OHD) level (parametric approach) and 25-OHD deficiency (non-parametric approach) with preeclampsia. As well, for the parametric part, we used receiver operating characteristic (ROC) curve model. MATERIALS AND METHODS We used Web of Science, PubMed and Science Direct data bases through searching in titles. Google Scholar search engine was used in order to find missing papers. Finally 23 studies were imported. Both random and fixed models were reported. RESULTS Based on the forest plot, lower levels of 25-OHD were significantly associated with risk of preeclampsia (fixed and random P < 0.001). Based on the forest plot, vitamin D deficiency (25-OHD < 20 ng/ml) was significantly associated with risk of preeclampsia (fixed P < 0.0001; random P = 0.0029; fixed OR = 1.33; random OR = 1.54). Based on ROC curve results, we found 2 cutoffs of 10.60 and 20.05 ng/ml. CONCLUSION Women with vitamin D deficiency at cutoff 20 ng/ml are more at risk of preeclampsia. This association can be specific up to 90% at 10.60 ng/ml cutoff. Treatment of vitamin D deficiency is necessary before pregnancy.
2.
Novel ideas about salt, blood pressure, and pregnancy.
Rakova, N, Muller, DN, Staff, AC, Luft, FC, Dechend, R
Journal of reproductive immunology. 2014;:135-139
Abstract
The molecular mechanisms leading to preeclampsia are poorly understood. It has been related to certain immune mechanisms, as well as the pathological regulation of the renin-angiotensin system together with perturbed salt and plasma volume regulation. Finally, a non-specific, vascular, inflammatory response is generated, which leads to the clinical syndrome. Here, we present novel findings in salt (NaCl) metabolism implying that salt is not only important in blood pressure control and volume homeostasis, but also in immune regulation. Sodium and chloride can be stored without accumulation of water in the interstitium at hypertonic concentrations through interactions with proteoglycans. Macrophages in the interstitium act as osmosensors for salt, producing increased amounts of vascular endothelial factor C, which increases the density of the lymph-capillary network and the production of nitric oxide in vessels. An increased interstitial salt concentration activates the innate immune system, especially Th17 cells, and may be an important trigger for autoimmune diseases. The novel findings with the idea of sodium storage and local mechanisms of volume and immune regulation are appealing for preeclampsia and may unify the "immune" and "vascular" hypotheses of preeclampsia.
3.
Is vitamin E a safe prophylaxis for preeclampsia?
Banerjee, S, Chambers, AE, Campbell, S
American journal of obstetrics and gynecology. 2006;(5):1228-33
Abstract
The prophylactic use of vitamins E and C for the prevention of preeclampsia is currently being evaluated in multiple clinical trials in Canada, Mexico, the United Kingdom, the United States, and other developing countries. In addition to its antioxidant capacity, exogenous vitamin E may prevent an immunologic switch (Th1 to Th2) that is vital for early-to late transition in normal pregnancies. Moreover, vitamin E could be a potential interferon-gamma (IFN-gamma) mimic facilitating persistent proinflammatory reactions at the fetal-maternal interface. These untoward effects of dietary intake of vitamin E may be more pronounced in those treated cases that fail to develop preeclampsia. A critical test of this hypothesis would be to establish whether, under variable O2 tension, vitamin E is capable of affecting cytokine signaling in placental trophoblasts and maternal immune effector cells, both in early and late human pregnancies.
4.
Vitamin D for the prevention of preeclampsia? A hypothesis.
Hyppönen, E
Nutrition reviews. 2005;(7):225-32
Abstract
Preeclampsia has been suggested to result from a partial breakdown of tolerance to the developing fetus after maternal immune maladaptation. Several of the proposed immunomodulatory properties of the hormonal vitamin D system could potentially have beneficial effects for successful maintenance of pregnancy. Preeclampsia is characterized by marked changes in vitamin D metabolism. This paper reviews the evidence suggesting that the immunomodulatory properties of 1,25(OH)2D may play a key role in maintaining immunological tolerance in pregnancy, and proposes that ensuring adequate vitamin D status/intake may help in the prevention and management of preeclampsia.