Lipoxin A4 Is Increased in the Plasma of Preeclamptic Women

Erythrocyte fatty acids and desaturase indices in early pregnancy are associated with risk of preeclampsia

Preeclampsia (PE) is a pregnancy disorder that may be associated with inadequate maternal nutrition. Fatty acids are vital for placental and fetal growth. Fatty acid desaturases, key enzymes influencing the metabolism of polyunsaturated fatty acids, are reported to be associated with cardiometabolic risk. Any imbalance in the levels of omega-3 and omega-6 fatty acids can result in increased inflammatory response. The current study reports the levels of erythrocyte fatty acids and desaturase index across gestation in women who develop PE (n = 108) and compares them with non-PE women (n = 216). Maternal erythrocyte fatty acids were measured at 4 time points during pregnancy (i.e., 11-14, 18-22, 26-28 weeks and at delivery) using gas chromatography. Maternal total erythrocyte saturated fatty acids and omega-6/omega-3 fatty acid ratio was higher in the PE group as compared to the non-PE group at 11-14 weeks and 18-22 weeks respectively. Maternal Δ5 desaturase index was lower while Δ6 desaturase index was higher in the PE group at 11-14 and 18-22 weeks. Maternal stearoyl CoA desaturase-18 (SCD-18) index was lower at 11-14 weeks and at delivery. These changes were mainly observed in the early onset PE (EOP) group. Δ6 desaturase index at 11-14 weeks predicted the risk of EOP. Imbalance in fatty acid levels and desaturase indices predate the clinical diagnosis of PE, indicating their role in its pathophysiology. Measurement of fatty acids and desaturase indices in early pregnancy merits evaluation as predictors of risk of PE.

Lipoxins and their relationship with inflammation-associated diseases. A systematic review

AIM

To determine the relationship of lipoxin levels with inflammation and disease development in adults and children.

METHODS

We conducted a systematic review. The search strategy included Medline, Ovid, EMBASE, LILACS, The Cochrane Central Register of Controlled Trials, and Open Gray. We included Clinical trials, cohort studies, case-control studies, and cross-sectional studies. Animal experiments were excluded.

RESULTS

We included fourteen studies in this review, nine consistently showing decreased lipoxin levels and anti-inflammatory markers or increased pro-inflammatory markers in cardiovascular disease, metabolic syndrome, Alzheimer's disease, periodontitis, or autism. Five studies showed increased lipoxin levels and pro-inflammatory markers in pre-eclampsia, asthma, and coronary disease. On the other hand, one showed increased lipoxin levels and decreased pro-inflammatory marker levels.

CONCLUSIONS

Decreases in lipoxins are associated with developing pathologies such as cardiovascular and neurological diseases, indicating that lipoxins protect against these pathologies. However, in other pathologies, such as asthma, pre-eclampsia, and periodontitis, which are associated with chronic inflammation despite increased levels of LXA4, the increase in inflammation suggests a possible failure of this regulatory pathway. Therefore, further studies are necessary to evaluate the role of LXA4 in the pathogenesis of inflammatory diseases.

Decompression Mechanism of Radish Seed in Prehypertension Rats through Integration of Transcriptomics and Metabolomics Methods

Radish seed (RS), the dried ripe seed of Raphanus sativus L., is widely used in traditional Chinese medicine (TCM) to reduce blood pressure. However, the molecular and pharmacological mechanisms underlying its therapeutic effects are still unclear. In this study, we analyzed the effects of RS in a rat model of prehypertension and assessed the mechanistic basis by integrating transcriptomics and metabolomics. RS administration significantly reduced blood pressure in prehypertensive male Wistar rats, negatively regulated endothelin-1, increased nitric oxide levels, and reduced the exfoliation of endothelium cells. In vitro vascular ring experiments further confirmed the effects of RS on vascular endothelial cells. Furthermore, we identified 65 differentially expressed genes (DEGs; P _adj < 0.05 and fold change (FC) > 2) and 52 metabolites (VIP > 1, P < 0.05 and FC ≥ 2 or ≤0.5) in the RS intervention group using RNA-seq and UPLC-MS/MS, respectively. A network of the DEGs and the metabolites was constructed,q which indicated that RS regulates purine metabolism, linoleic acid metabolism, arachidonic acid metabolism, circadian rhythm, and phosphatidylinositol signaling pathway, and its target genes are Pik3c2a, Hspa8, Dnaja1, Arntl, Ugt1a1, Dbp, Rasd1, and Aldh1a3. Thus, the antihypertensive effects of RS can be attributed to its ability to improve vascular endothelial dysfunction by targeting multiple genes and pathways. Our findings provide new insights into the pathological mechanisms underlying prehypertension, along with novel targets for the prevention and treatment of hypertension.

Inflammation and oxidative stress as mediators of the impacts of environmental exposures on human pregnancy: Evidence from oxylipins

Inflammation and oxidative stress play major roles in healthy and pathological pregnancy. Environmental exposure to chemical pollutants may adversely affect maternal and fetal health in pregnancy by dysregulating these critical underlying processes of inflammation and oxidative stress. Oxylipins are bioactive lipids that play a major role in regulating inflammation and increasing lines of evidence point towards an importance in pregnancy. The biosynthetic production of oxylipins requires oxygenation of polyunsaturated fatty acids, which can occur through several well-characterized enzymatic and nonenzymatic pathways. This review describes the state of the science of epidemiologic evidence on oxylipin production in pregnancy and its association with 1) key pregnancy outcomes and 2) environmental exposures. We searched PubMed for studies of pregnancy that measured one or more oxylipin analytes during pregnancy or delivery. We evaluated oxylipin associations with three categories of adverse pregnancy outcomes, including preeclampsia, preterm birth, and fetal growth restriction, along with several categories of environmental pollutants. The majority of studies evaluated one to two oxylipins, most of which focused on oxylipins produced from nonenzymatic processes of oxidative stress. However, an increasing number of recent studies have leveraged technological advancements to profile a large number of oxylipins produced from distinct biosynthetic pathways. Although the literature indicated robust evidence that oxylipins produced via nonenzymatic pathways are associated with pregnancy outcomes and environmental exposures, evidence for enzymatically produced oxylipins showed that associations may differ between biosynthetic pathways. Along with summarizing this evidence, we review promising therapeutic options to regulate oxylipin production and provide a set of recommendations for future epidemiologic studies in these research areas. Further evidence is needed to improve our understanding of how oxylipins may act as key biological mediators for the adverse effects of environmental pollutants on pregnancy outcomes.

Mediators of inflammation resolution and vasoactive eicosanoids in gestational diabetes and preeclampsia

OBJECTIVE

Women with gestational diabetes (GDM) have an increased risk of preeclampsia and postpartum diabetes. Inflammation associates with both GDM and preeclampsia. This study examined specialized proresolving mediators (SPM) that direct inflammation resolution and eicosanoids that are involved in inflammation, in relation to the development of preeclampsia and ongoing postpartum glucose intolerance in GDM.

METHODS

Participants were selected from a prospective study examining the development of preeclampsia in women with GDM. Four groups of age-matched women were studied: GDM ( n  = 20), GDM who developed preeclampsia (GDM+PE, n  = 21), GDM who remained glucose-intolerant postpartum (GDM+PPIGT, n  = 20), or pregnancies with glucose tolerance within the normal range (NGT, n  = 21). Measurement of SPM (E-series resolvins and D-series resolvins), SPM pathway intermediates (14-HDHA, 18-HEPE and 17-HDHA), 20-hydroxyeicosatetraenoic acid (20-HETE), and the urinary metabolite of the vasodilator prostacyclin 2,3-dinor-6-Keto-PGF 1α , were made at 28, 32 and 36 weeks gestation and at 6 months postpartum.

RESULTS

Compared with GDM, GDM+PE had elevated levels of 20-HETE and the SPM pathway intermediates 14-HDHA, 18-HEPE, 17-HDHA, at 32 weeks, and the SPM RvE1 at 32 and 36 weeks gestation. Compared with NGT and regardless of whether they developed preeclampsia or PPIGT, GDM had lower levels of 2,3-dinor-6-Keto-PGF 1α during pregnancy.

CONCLUSION

Reduced levels of the prostacyclin metabolite 2,3-dinor-6-Keto-PGF 1α may contribute to the increased risk of preeclampsia in women with GDM. The increase in 20-HETE, a vasoconstrictor and mediator of inflammation, and SPM that contribute to inflammation resolution, prior to the onset of preeclampsia require further investigation to clarify their clinical significance.

Infection with Listeria monocytogenes alters the placental transcriptome and eicosanome

INTRODUCTION

Placental infection and inflammation are risk factors for adverse pregnancy outcomes, including preterm labor. However, the mechanisms underlying these outcomes are poorly understood.

METHODS

To study this response, we have employed a pregnant mouse model of placental infection caused by the bacterial pathogen Listeria monocyogenes, which infects the human placenta. Through in vivo bioluminescence imaging, we confirm the presence of placental infection and quantify relative infection levels. Infected and control placentas were collected on embryonic day 18 for RNA sequencing to evaluate gene expression signatures associated with infection by Listeria.

RESULTS

We identified an enrichment of genes associated with eicosanoid biosynthesis, suggesting an increase in eicosanoid production in infected tissues. Because of the known importance of eicosanoids in inflammation and timing of labor, we quantified eicosanoid levels in infected and uninfected placentas using semi-targeted mass spectrometry. We found a significant increase in the concentrations of several key eicosanoids: leukotriene B4, lipoxin A4, prostaglandin A2, prostaglandin D2, and eicosatrienoic acid.

DISCUSSION

Our study provides a likely explanation for dysregulation of the timing of labor following placental infection. Further, our results suggest potential biomarkers of placental pathology and targets for clinical intervention.

Longitudinal assessment of leukotriene B4, lipoxin A4, and resolvin D1 plasma levels in pregnant women with risk factors for preeclampsia

OBJECTIVES

We carried out a longitudinal study to compare leukotriene B4 (LTB4), lipoxin A4 (LXA4), and resolvin D1 (RvD1) levels in pregnant women with risk factors for PE - who did (N = 11) or did not develop (N = 17) this clinical condition.

DESIGN & METHODS

For both groups, plasma levels of the lipid mediators were measured using immunoassays at 12-19, 20-29, and 30-34 weeks of gestation.

RESULTS

LTB4 tended to be upregulated throughout gestation in women who developed PE. Moreover, this increase was significant at 30-34 weeks. Although LXA4 levels also tended to be higher in the PE group, this difference was not significant for the evaluated gestational periods. Pregnant women with PE had lower RvD1 levels and a low RvD1/LTB4 ratio at 30-34 weeks, compared to those in the normotensive pregnant women. Contrarily, RvD1 levels increased at weeks 12-19 in pregnant women who developed PE. Particularly, LXA4 and RvD1 levels were higher at 30-34 weeks than those at 20-29 weeks considering both groups of women. We observed an interaction between the gestational outcome and the gestational period in case of RvD1.

CONCLUSIONS

The imbalance among LTB4, LXA4, and RvD1 levels in these preeclamptic women is consistent with the excessive inflammation that underlies the pathogenesis of PE. Although our data highlight the potential for the use of these lipid mediators as clinical markers for PE development, future longitudinal studies must be carried out to confirm these findings.

Promoting resolution in kidney disease: are we nearly there yet?

PURPOSE OF REVIEW

Nephrology lacks effective therapeutics for many of the presentations and diseases seen in clinical practice. In recent decades, we have come to understand the central place of inflammation in initiating and propagating kidney disease, and, research in more recent years has established that the resolution of inflammation is a highly regulated and active process. With this, has evolved an appreciation that this aspect of the host inflammatory response is defective in kidney disease and led to consideration of a therapeutic paradigm aiming to harness the activity of the molecular drivers of the resolution phase of inflammation. Fatty-acid-derived Specialized pro-resolving mediators (SPMs), partly responsible for resolution of inflammation have gained traction as potential therapeutics.

RECENT FINDINGS

We describe our current understanding of SPMs for this purpose in acute and chronic kidney disease. These studies cement the place of inflammation and its defective resolution in the pathogenesis of kidney disease, and highlight new avenues for therapy.

SUMMARY

Targeting resolution of inflammation is a viable approach to treating kidney disease. We optimistically look forward to translating these experimental advances into tractable therapeutics to treat kidney disease.

The Obligatory Role of the Acetylcholine-Induced Endothelium-Dependent Contraction in Hypertension: Can Arachidonic Acid Resolve this Inflammation?

The endothelium produces many substances that can regulate vascular tone. Acetylcholine is a widely used pharmacological tool to assess endothelial function. In general, acetylcholine binds to G-protein coupled muscarinic receptors that mediate a transient elevation in intracellular, free calcium. This intracellular rise in calcium is responsible for triggering several cellular responses, including the synthesis of nitric oxide, endothelium- derived hyperpolarizing factor, and eicosanoids derived from arachidonic acid. Endothelial arachidonic acid metabolism is also an important signaling pathway for mediating inflammation. Therefore, in conditions with sustained and excessive inflammation such as hypertension, arachidonic acid serves as a substrate for the synthesis of several vasoconstrictive metabolites, predominantly via the cyclooxygenase and lipoxygenase enzymes. Cyclooxygenase and lipoxygenase products can then activate G-protein coupled receptors expressed on vascular smooth muscle cells to causes contractile responses. As a result, acetylcholine-induced contraction due to arachidonic acid is a commonly observed feature of endothelial dysfunction and vascular inflammation in hypertension. In this review, we will critically analyze the literature supporting this concept, as well as address the potential underlying mechanisms, including the possibility that arachidonic acid signaling is diverted away from the synthesis of pro-resolving metabolites in conditions such as hypertension.

Exploring the role of LC-PUFA metabolism in pregnancy complications

Maternal nutrition during pregnancy plays a significant role in growth and development of the placenta and influencing pregnancy outcome. Suboptimal nutritional status during early gestational period compromises the normal course of pregnancy leading to adverse maternal and fetal outcomes. Omega-3 and omega-6 long chain polyunsaturated fatty acids (LC-PUFA) are important for the growth and development of the placenta. Maternal fatty acids and their metabolites influence the normal course of pregnancy by regulating cell growth and development, cell signaling, regulate angiogenesis, modulate inflammatory responses and influence various structural and functional processes. Alterations in LC-PUFA and their metabolites may result in inadequate spiral artery remodeling or placental angiogenesis leading to structural and functional deficiency of the placenta which contributes to several pregnancy complications like preeclampsia, gestational diabetes mellitus, intrauterine growth restriction, and results in adverse birth outcomes. In this review, we summarize studies examining the role of fatty acids and their metabolites in pregnancy. We also discuss the possible molecular mechanisms through which LC-PUFA influences placental growth and development. Studies have demonstrated that omega-3 fatty acid supplementation lowers the incidence of preterm births, but its effect on reducing pregnancy complications are inconclusive.

The 15-Epilipoxin-A4 Pathway with Prophylactic Aspirin in Preventing Preeclampsia: A Longitudinal Cohort Study

INTRODUCTION

The benefit of aspirin in preventing preeclampsia is increasingly recognized; however, its mechanism of action remains unclear. Nonobstetric studies have described an anti-inflammatory effect of aspirin through the 15-epilipoxin-A4 pathway (aspirin-triggered lipoxin [ATL]). However, the anti-inflammatory mechanism of aspirin in the prevention of preeclampsia remains unknown.

OBJECTIVE/HYPOTHESIS

To examine (1) the difference in longitudinal endogenous lipoxin-A4 (En-Lipoxin-A4) concentration in low-risk (LR) and high-risk (HR) pregnancies, and (2) the effect of aspirin on endogenous ATL concentration and the associated effect on cytokine profile of HR women.

METHODS

Plasma from 220 HR women was collected at 12, 16, 20, 24, 28, 32, and 36 weeks of gestation. Adherence to aspirin was biochemically verified. Plasma En-Lipoxin-A4 and ATL concentrations were analyzed using liquid chromatography mass spectrometry, and cytokines, interleukin (IL)-10, tumor necrosis factor-α, interferon-γ, IL-8, and IL-1β, with the high-sensitivity multibead Luminex® assay.

RESULTS

HR women have up to 70% lower plasma concentration of En-Lipoxin-A4 (P < 0.001) than LR women. HR women with adequate aspirin adherence (HR-AA) (n = 82) had higher plasma concentration of ATL (P < .001), lower concentration of IL-8 from 16 to 36 weeks of gestation (P < .001), and increased IL-10 concentration from 16 to 28 weeks of gestation (P = .03) compared with high-risk women who were not on aspirin (HR-NA). HR-AA who did not develop preeclampsia had higher plasma En-lipoxin-A4 (P < .001), ATL (P = .02), and IL-10 concentrations (P < .001) with lower IL-8 concentration (P = .004) than HR women who developed preeclampsia.

DISCUSSION

Plasma concentration of En-Lipoxin-A4 is lower in HR women than in LR controls. Adequate adherence with aspirin results in an increase in ATL and IL-10 with reduced IL-8 plasma concentration. This study suggests a potential anti-inflammatory role of aspirin through the ATL pathway with prophylactic aspirin in HR pregnant women.

Polyunsaturated Fatty Acid Diet and Upregulation of Lipoxin A4 Reduce the Inflammatory Response of Preeclampsia

The aim of this study was to investigate the effects and mechanisms of polyunsaturated fatty acids (PUFAs) and lipoxin A4 (LXA4) on preeclampsia (PE). The LXA4 level was significantly reduced in PE rats. The PUFA diet upregulated the expressions of lipoxygenase 12 (LOX12) and lipoxygenase 15 (LOX15) and downregulated those of cyclooxygenase-2, tumor necrosis factor-α (TNF-α), and endoglin. Lipopolysaccharides could inhibit cell growth and cause inflammatory response, while the presence of PUFAs inhibited the inflammatory response and promoted the expressions of LOX12, LOX15, and LXA4. Nordihydroguaiaretic acid (NDGA) regulated LXA4 expression and inflammation levels by affecting LOX. Inhibition of lipoxygenase 5 activity by NDGA upregulated the expressions of LOX12 and LOX15, while LXA4 reversed LXA4, nitric oxide downregulation, and TNF-α upregulation by NDGA. A decrease in LXA4 levels played an important role in the development and progression of PE.

Changes of lipoxin levels during pregnancy and the monthly-cycle, condition the normal course of pregnancy or pathology

OBJECTIVE AND DESIGN

The purpose of the review was to gather information on the role and possibilities of using lipoxin in the treatment of infertility and maintaining a normal pregnancy. Ovulation, menstruation, embryo implantation, and childbirth are reactions representing short-term inflammatory events involving lipoxin activities. Lipoxin A4 (LXA4) is an arachidonic acid metabolite, and in cooperation with its positional isomer lipoxin B4 (LXB4), it is a major lipoxin in mammals. Biosynthesis process occurs in two stages: in the first step, the donor cell releases the eicosanoid intermediate; secondarily, the acceptor cell gets and converts the intermediate product into LXA4 (leukocyte/platelet interaction).

RESULTS

Generating lipoxin synthesis may also be triggered by salicylic acid, which acetylates cyclooxygenase-2. Lipoxin A4 and its analogues are considered as specialized pro-resolving mediators. LXA4 is an important component for a proper menstrual cycle, embryo implantation, pregnancy, and delivery. Its level in the luteal phase is high, while in the follicular phase, it decreases, which coincides with an increase in estradiol concentration with which it competes for the receptor. LXA4 inhibits the progression of endometriosis. However, during the peri-implantation period, before pregnancy is confirmed clinically, high levels of LXA4 can contribute to early pregnancy loss and may cause miscarriage. After implantation, insufficient LXA4 levels contribute to incorrect maternal vessel remodeling; decreased, shallow trophoblastic invasion; and the immuno-energetic abnormality of the placenta, which negatively affects fetal growth and the maintenance of pregnancy. Moreover, the level of LXA4 increases in the final stages of pregnancy, allowing vessel remodeling and placental separation.

METHODS

The review evaluates the literature published in the PubMed and Embase database up to 31 December 2019. The passwords were checked on terms: lipoxin and pregnancy with combined endometriosis, menstrual cycle, implantation, pre-eclampsia, fetal growth restriction, and preterm labor.

CONCLUSIONS

Although no human studies have been performed so far, the cell and animal model study results suggest that LXA4 will be used in obstetrics and gynecology soon.

Changes in plasma lipoxin A4, resolvins and CD59 levels after ischemic and traumatic brain injuries in rats

Ischemic and traumatic brain injuries are the major acute central nervous system disorders that need to be adequately diagnosed and treated. To find biomarkers for these acute brain injuries, plasma levels of some specialized pro-resolving mediators (SPMs, i.e., lipoxin A4 [LXA4], resolvin [Rv] E1, RvE2, RvD1 and RvD2), CD59 and interleukin (IL)-6 were measured at 0, 6, 24, 72, and 168 h after global cerebral ischemic (GCI) and traumatic brain injuries (TBI) in rats. Plasma LXA4 levels tended to increase at 24 and 72 h after GCI. Plasma RvE1, RvE2, RvD1, and RvD2 levels showed a biphasic response to GCI; a significant decrease at 6 h with a return to the levels of the sham group at 24 h, and again a decrease at 72 h. Plasma CD59 levels increased at 6 and 24 h post-GCI, and returned to basal levels at 72 h post-GCI. For TBI, plasma LXA4 levels tended to decrease, while RvE1, RvE2, RvD1, and RvD2 showed barely significant changes. Plasma IL-6 levels were significantly increased after GCI and TBI, but with different time courses. These results show that plasma LXA4, RvE1, RvE2, RvD1, RvD2, and CD59 levels display differential responses to GCI and TBI, and need to be evaluated for their usefulness as biomarkers.

Pre-eclampsia is associated with reduced resolvin D1 and maresin 1 to leukotriene B4 ratios in the plasma

PROBLEM

Omega-3 and omega-6 fatty acids can be endogenously converted into mediators with pro-inflammatory (eg, leukotriene B4/LTB4) or anti-inflammatory/pro-resolving activities (eg, resolvin D1/RvD1 and maresin 1/MaR1). Recent data indicate an imbalance of LTB4 and MaR1 levels in pre-eclampsia (PE), but the relative production of these mediators, including RvD1, and the role of these mediators in the disease pathogenesis remain unclear. Therefore, this study aimed to investigate the plasma levels of LTB4, RvD1, and MaR1 in pregnant women with or without PE and non-pregnant controls and their association with clinical/laboratory parameters of PE women.

METHOD OF STUDY

LTB4, RvD1, and MaR1 plasma levels were measured by competitive enzyme immunoassay in 19 non-pregnant, 20 normotensive pregnant, and 21 PE women.

RESULTS

Plasma concentrations of LTB4 were higher and RvD1 were lower in PE women than in normotensive pregnant women, who presented higher levels of LTB4 and similar levels of RvD1 to non-pregnant women. MaR1 levels did not differ among the groups. Pre-eclampsia women had decreased RvD1/LTB4 and MaR1/LTB4 ratios. Considering only the PE group, positive correlations were observed among all the mediators tested, between LTB4 and white blood cell count and between RvD1 and creatinine levels. However, all lipid mediators correlated negatively with body mass index before pregnancy. LTB4 also correlated negatively with maternal age.

CONCLUSION

Our findings suggest that the PE state results in systemic overproduction of LTB4 in relation to RvD1 and MaR1, and that these lipid mediators may be involved with the disease pathogenesis.

Update on oxidative stress and inflammation in pregnant women, unborn children (nasciturus), and newborns - Nutritional and dietary effects

The scientific background of perinatal pathology, regarding both mother and offspring, from the lipidomic perspective, has highlighted the possibility of identifying new, promising clinical markers of oxidative stress and inflammation, closely related to the normal development of unborn and newborn children, together with their application. In this regard, in recent years, significant advances have been achieved, assisted by both newly developed analytical tools and basic knowledge on the biological implications of oxylipins. Hence, in the light of this recent progress, this review aims to provide an update on the relevance of human oxylipins during pregnancy and in the unborn and newborn child, covering two fundamental aspects. Firstly, the evidence from human clinical studies and dietary intervention trials will be used to shed light on the extent to which dietary supplementation can modulate the lipidomic markers of oxidative stress and inflammation in the perinatal state, emphasizing the role of the placenta and metabolic disturbances in the mother and fetus. The second part of this article comprises a review of existing data on specific pathophysiological aspects of human reproduction, in relation to lipidomic markers in pregnant women, unborn children, and newborn children. The information reviewed here evidences the current opportunity to correct reproductive disturbances, in the framework of lipidomics, by fine-tuning dietary interventions.

Resolution of inflammation pathways in preeclampsia-a narrative review

Preeclampsia (PE) is one of the leading causes of maternal morbidity and mortality worldwide. This disease is believed to occur in two stages with placental dysfunction in early pregnancy leading to maternal clinical findings after 20 weeks of gestation, as consequence of systemic inflammation, oxidative stress, and endothelial dysfunction. Much evidence suggests that PE women display an overshooting inflammatory response throughout pregnancy due to an unbalanced regulation of innate and adaptive immune responses. Recently, it has been suggested that dysregulation of endogenous protective pathways might be associated with PE etiopathogenesis. Resolution of inflammation is an active process coordinated by mediators from diverse nature that regulate key cellular events to restore tissue homeostasis. Inadequate or insufficient resolution of inflammation is believed to play an important role in the development of chronic inflammatory diseases, like PE. In this narrative review, we discuss possible pro-resolution pathways that might be compromised in PE women, which could be targets to novel therapeutic strategies in this disease.

Annexin A1 and specialized proresolving lipid mediators: promoting resolution as a therapeutic strategy in human inflammatory diseases

INTRODUCTION

The timely resolution of inflammation is essential to restore tissue homeostasis and to avoid chronic inflammatory diseases. Resolution of inflammation is an active process modulated by various proresolving mediators, including annexin A1 (AnxA1) and specialized proresolving lipid mediators (SPMs), which counteract excessive inflammatory responses and stimulate proresolving mechanisms. Areas covered: The protective effects of AnxA1 and SPMs have been extensively explored in pre-clinical animal models. However, studies investigating the function of these molecules in human diseases are just emerging. This review highlights recent advances on the role of proresolving mediators, and pharmacological opportunities of promoting resolution pathways in preclinical models and patients with various human diseases. Expert opinion: Dysregulation or 'failure' in proresolving mechanisms might be involved in the pathogenesis of chronic inflammatory diseases. Altered levels of proresolving mediators were found in a wide range of human diseases. In some cases, AnxA1 and SPMs are up-regulated in human blood and tissues but fail to engage in proresolving signaling and, hence, to regulate excessive inflammation. Thus, the new concept of 'resolution pharmacology' could be applied to compensate deficiency of endogenous proresolving mediators' generation and/or possible failures in the engagement of resolution pathways observed in many chronic inflammatory diseases.