Erythropoietin and Soluble Erythropoietin Receptor: A Role for Maternal Vascular Adaptation to High-Altitude Pregnancy

Peptides derived from growth factors: Exploring their diverse impact from antimicrobial properties to neuroprotection

Growth factor-derived peptides are bioactive molecules that play a crucial role in various physiological processes within the human body. Over the years, extensive research has revealed their diverse applications, ranging from antimicrobial properties to their potential in neuroprotection and treating various diseases. These peptides exhibit innate immune responses and have been found to possess potent antimicrobial properties against a wide range of pathogens. Growth factor-derived peptides have demonstrated the ability to promote neuronal survival, prevent cell death, and stimulate neural regeneration. As a result, they hold immense promise in the treatment of various neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and multiple sclerosis, as well as in the management of traumatic brain injuries. Moreover, growth factor-derived peptides have shown potential for supporting tissue repair and wound healing processes. By enhancing cell proliferation and migration, these peptides contribute to the regeneration of damaged tissues and promote a more efficient healing response. The applications of growth factor-derived peptides extend beyond their therapeutic potential in health; they also have a role in various disease conditions. For example, researchers have explored their influence on cancer cells, where some peptides have demonstrated anti-cancer properties, inhibiting tumor growth and promoting apoptosis in cancer cells. Additionally, their immunomodulatory properties have been investigated for potential applications in autoimmune disorders. Despite the immense promise shown by growth factor-derived peptides, some challenges need to be addressed. Nevertheless, ongoing research and advancements in biotechnology offer promising avenues to overcome these obstacles. The review summarizes the foundational biology of growth factors and the intricate signaling pathways in various physiological processes as well as diseases such as cancer, neurodegenerative disorders, cardiovascular ailments, and metabolic syndromes.

Nonerythropoietic Erythropoietin Mimetic Peptide ARA290 Ameliorates Chronic Stress-Induced Depression-Like Behavior and Inflammation in Mice

Major depressive disorder (MDD) is a highly prevalent psychiatric disorder. But the treatment of depression remains challenging. Anti-inflammatory treatments frequently produce antidepressant effects. EPO-derived helix-B peptide ARA290 has been reported to retain the anti-inflammatory and tissue-protective functions of EPO without erythropoiesis-stimulating effects. The effects of ARA290 on MDD remain elusive. This study established chronic unpredictable mild stress and chronic social defeat stress mouse models. Daily administration of ARA290 during chronic stress induction in two mouse models ameliorated depression-like behavior, similar to fluoxetine. With marginal effects on peripheral blood hemoglobin and red cells, ARA290 and fluoxetine reversed chronic stress-induced increased frequencies and/or numbers of CD11b+Ly6Ghi neutrophils and CD11b+Ly6Chi monocytes in the bone marrow and meninges. Furthermore, both drugs reversed chronic stress-induced microglia activation. Thus, ARA290 ameliorated chronic stress-induced depression-like behavior in mice through, at least partially, its anti-inflammatory effects.

A Critical Analysis of the Automated Hematology Assessment in Pregnant Women at Low and at High Altitude: Association between Red Blood Cells, Platelet Parameters, and Iron Status

The objectives of the study were to determine differences in the parameters of red blood cells (RBC), white blood cells (WBC), and platelets at low altitude (LA) and at high altitude (HA) and with the gestation being advanced, and to determine correlations between parameters of RBC and platelets. We also studied the association of RBC and platelets with markers of iron status. In addition, markers of iron status and inflammation were measured and compared at each trimester of gestation in pregnant women at LA and HA. A cross-sectional comparative study was conducted at Lima (150 m above sea level) and Cusco at 3400 m above sea level from May to December 2019. Hematological parameters in pregnant women (233 at LA and 211 at HA) were analyzed using an automated hematology analyzer. Serum ferritin levels, soluble transferrin receptor (sTfR), hepcidin, erythropoietin, testosterone, estradiol, and interleukin-6 (IL6) levels were measured by ELISA. One-way ANOVA supplemented with post hoc test, chi-square test, and Pearson correlation test statistical analyses were performed. p < 0.05 was considered significant. Pregnant woman at HA compared to LA had significantly lower WBC (p < 0.01), associated with higher parameters of the RBC, except for the mean corpuscular volume (MCV) that was no different (p > 0.05). Platelets and mean platelet volume (MPV) were higher (p < 0.01), and platelet distribution width (PDW) was lower at HA than at LA (p < 0.01). A higher value of serum ferritin (p < 0.01), testosterone (p < 0.05), and hepcidin (p < 0.01) was observed at HA, while the concentration of sTfR was lower at HA than at LA (p < 0.01). At LA, neutrophils increased in the third trimester (p < 0.05). RBC parameters decreased with the progress of the gestation, except RDW-CV, which increased. The platelet count decreased and the MPV and PDW were significantly higher in the third trimester. Serum ferritin, hepcidin, and serum testosterone decreased, while sTfR and serum estradiol increased during gestation. At HA, the WBC and red blood cell distribution width- coefficient of variation (RDW-CV), PCT, and serum IL-6 did not change with gestational trimesters. RBC, hemoglobin (Hb), hematocrit (Hct), mean corpuscular hemoglobin concentration (MCHC), and platelet count were lower as gestation advanced. MCV, MPV, and PDW increased in the third trimester. Serum ferritin, testosterone, and hepcidin were lower in the third trimester. Serum estradiol, erythropoietin, and sTfR increased as gestation progressed. Direct or inverse correlations were observed between RBC and platelet parameters and LA and HA. A better number of significant correlations were observed at HA. Hb, Hct, and RDW-CV showed a significant correlation with serum ferritin at LA and HA. Of these parameters, RDW-CV and PDW showed an inversely significant association with ferritin (p < 0.05). In conclusion, a different pattern was observed in hematological markers as well as in iron status markers between pregnant women at LA and HA. In pregnant women a significant correlation between several RBC parameters with platelet marker parameters was also observed. Data suggest that pregnant women at HA have adequate iron status during pregnancy as reflected by higher serum ferritin levels, lower sTfR levels, and higher hepcidin values than pregnant women at LA.

Erythropoietin Mimetic Peptide (pHBSP) Corrects Endothelial Dysfunction in a Rat Model of Preeclampsia

Preeclampsia is a severe disease of late pregnancy. Etiological factors and a pathogenetic pattern of events still require significant clarification, but it is now recognized that a large role is played by placentation disorders and emerging endothelial dysfunction. The administration of short-chain peptides mimicking the spatial structure of the B erythropoietin chain may become one of the directions of searching for new drugs for preeclampsia prevention and therapy. Simulation of ADMA-like preeclampsia in Wistar rats was performed by the administration of a non-selective NOS blocker L-NAME from the 14th to 20th day of pregnancy. The administration of the pHBSP at the doses of 10 µg/kg and 250 µg/kg corrected the established morphofunctional disorders. The greatest effect was observed at a dose of 250 µg/kg. There was a decrease in systolic and diastolic blood pressure by 31.2 and 32.8%, respectively (p < 0.0001), a decrease in the coefficient of endothelial dysfunction by 48.6% (p = 0.0006), placental microcirculation increased by 82.8% (p < 0.0001), the NOx concentration was increased by 42,6% (p = 0.0003), the greater omentum edema decreased by 11.7% (p = 0.0005) and proteinuria decreased by 76.1% (p < 0.0002). In addition, there was an improvement in the morphological pattern of the fetoplacental complex and the ratio of BAX to Bcl-2 expression which characterizes the apoptotic orientation of the cells.

Preeclampsia: The Interplay Between Oxygen-Sensitive miRNAs and Erythropoietin

Changes in the oxygen partial pressure caused by a violation of uteroplacental perfusion are considered a powerful inducer of a cascade of reactions leading to the clinical manifestation of preeclampsia (PE). At the same time, the induction of oxygen-dependent molecule expression, in particular, miRNA and erythropoietin, is modulated. Therefore, the focus of our study was aimed at estimating the miRNA expression profile of placental tissue and blood plasma in pregnant women with preeclampsia using deep sequencing and quantitative RT-PCR, as well as determining the concentration of erythropoietin. The expression of miR-27b-3p, miR-92b-3p, miR-125b-5p, miR-181a-5p, and miR-186-5p, as regulated by hypoxia/reoxygenation, was significantly increased in blood plasma during early-onset preeclampsia. The possibility of detecting early PE according to the logistic regression model (miR-92b-3p, miR-125b-5p, and miR-181a-5p (AUC = 0.91)) was evaluated. Furthermore, the erythropoietin level, which is regulated by miR-125b-5p, was significantly increased. According to PANTHER14.1, the participation of these miRNAs in the regulation of pathways, such as the hypoxia’s response via HIF activation, oxidative stress response, angiogenesis, and the VEGF signaling pathway, were determined.

The Genome Landscape of Tibetan Sheep Reveals Adaptive Introgression from Argali and the History of Early Human Settlements on the Qinghai-Tibetan Plateau

Tibetan sheep are the most common and widespread domesticated animals on the Qinghai-Tibetan Plateau (QTP) and have played an essential role in the permanent human occupation of this high-altitude region. However, the precise timing, route, and process of sheep pastoralism in the QTP region remain poorly established, and little is known about the underlying genomic changes that occurred during the process. Here, we investigate the genomic variation in Tibetan sheep using whole-genome sequences, single nucleotide polymorphism arrays, mitochondrial DNA, and Y-chromosomal variants in 986 samples throughout their distribution range. We detect strong signatures of selection in genes involved in the hypoxia and ultraviolet signaling pathways (e.g., HIF-1 pathway and HBB and MITF genes) and in genes associated with morphological traits such as horn size and shape (e.g., RXFP2). We identify clear signals of argali (Ovis ammon) introgression into sympatric Tibetan sheep, covering 5.23-5.79% of their genomes. The introgressed genomic regions are enriched in genes related to oxygen transportation system, sensory perception, and morphological phenotypes, in particular the genes HBB and RXFP2 with strong signs of adaptive introgression. The spatial distribution of genomic diversity and demographic reconstruction of the history of Tibetan sheep show a stepwise pattern of colonization with their initial spread onto the QTP from its northeastern part ∼3,100 years ago, followed by further southwest expansion to the central QTP ∼1,300 years ago. Together with archeological evidence, the date and route reveal the history of human expansions on the QTP by the Tang-Bo Ancient Road during the late Holocene. Our findings contribute to a depth understanding of early pastoralism and the local adaptation of Tibetan sheep as well as the late-Holocene human occupation of the QTP.

Pre- and postnatal environmental boron exposure and infant growth: Results from a mother-child cohort in northern Argentina

BACKGROUND

Experimental studies show developmental toxicity of boron and we recently found impaired weight and length in newborns of mothers exposed to boron through drinking water during pregnancy.

OBJECTIVES

To evaluate potential impact of pre- and postnatal boron exposure on infant anthropometry.

METHODS

In our mother-child cohort (n = 177) in Argentinean Andes, where drinking water concentrations of boron, lithium and arsenic have been found to vary considerably, we collected maternal blood and urine during and after pregnancy, placenta, breast milk, as well as infant urine and blood during the first 6 months of life. In all samples, boron and other potentially toxic elements were measured by ICP-MS. Infant weight (g), length (cm) and head circumference (cm) were measured at birth, 0-3 (n = 120) and/or 3-6 months (n = 120; 79 overlap) of age.

RESULTS

Boron concentrations in breast milk (range: 46-786 µg/L) correlated strongly with those in maternal serum (range: 47-624 µg/L; r^s = 0.94) 0-3 months post-partum. In multivariable-adjusted linear regression, urinary boron (log₂-transformed; range 60-9200 µg/L) in the youngest infants, but not maternal serum boron during pregnancy, was inversely associated with body weight at both 0-3 months (B: -141, 95% CI: -240; -42, p = 0.006) and 3-6 months (B: -200, 95% CI: -377; -23, p = 0.027). Infant urinary boron was also inversely associated with head circumference at 0-3 months (B: -0.39, 95% CI: -0.74; -0.04, p = 0.028), as well as length (B: -0.57, 95% CI: -1.1; -0.03, p = 0.040) and head circumference (B: -0.30, 95% CI: -0.64; 0.04, p = 0.083) at 3-6 months.

CONCLUSIONS

The observed first evidence that elevated environmental boron exposure in early infancy may adversely affect growth supports previous findings of boron-related impaired fetal growth. More research is needed to verify the findings at older age and in other populations.

Soluble erythropoietin receptor levels associate with inflammatory mediators but not with disease activity or cumulative organ damage in patients with systemic lupus erythematosus

The erythropoietin receptor (EpoR) stimulates erythrocyte proliferation after erythropoietin binding. EpoR belongs to the cytokine receptor superfamily and can be found on macrophages and endothelial cells. As there are no data on the role of EpoR systemic autoimmune diseases, we investigated the role of soluble EpoR (sEpoR) in patients with systemic lupus erythematosus (SLE). In a cross-sectional study we recorded clinical characteristics, disease activity (SLEDAI-2K) and organ damage (SDI). sEpoR, autoantibodies and cytokines were measured by enzyme-linked immunosorbent assay (ELISA) in SLE patients (n = 100) and compared with a rheumatoid arthritis (RA) cohort (n = 57) and a cohort with non-inflammatory back pain (NIBP; n = 89). Data were analysed with non-parametric techniques. We found no significant difference in sEpoR levels across the SLE, RA and NIBP groups and sEpoR levels were similar in patients with (6% of SLE and 31% of RA) or without anaemia. sEpoR levels were unrelated to haemoglobin levels, SLEDAI-2K or SDI scores, but in both cohorts correlated with levels for C-reactive protein (CRP), interleukin-6 (IL-6), tumour necrosis factor (TNF) and IL-1 (all P < 0.001). sEpoR levels are not involved in anaemia or erythropoietin resistance in SLE and RA patients, but closely mirror the underlying inflammatory process. This suggests that increased shedding of sEpoR during inflammation occurs at other sites than bone marrow.

Early Gestational Hypoxia and Adverse Developmental Outcomes

Hypoxia is a normal and essential part of embryonic development. However, this state may leave the embryo vulnerable to damage when oxygen supply is disturbed. Embryofetal response to hypoxia is dependent on duration and depth of hypoxia, as well as developmental stage. Early postimplantation rat embryos were resilient to hypoxia, with many surviving up to 1.5 hr of uterine clamping, while most mid-gestation embryos were dead after 1 hour of clamping. Survivors were small and many had a range of defects, principally terminal transverse limb reduction defects. Similar patterns of malformations occurred when embryonic hypoxia was induced by maternal hypoxia, interruption of uteroplacental flow, or perfusion and embryonic bradycardia. There is good evidence that high altitude pregnancies are associated with smaller babies and increased risk of some malformations, but these results are complicated by increased risk of pre-eclampsia. Early onset pre-eclampsia itself is associated with small for dates and increased risk of atrio-ventricular septal defects. Limb defects have clearly been associated with chorionic villus sampling, cocaine, and misoprostol use. Similar defects are also observed with increased frequency among fetuses who are homozygous for thalassemia. Drugs that block the potassium current, whether as the prime site of action or as a side effect, are highly teratogenic in experimental animals. They induce embryonic bradycardia, hypoxia, hemorrhage, and blisters, leading to transverse limb defects as well as craniofacial and cardiovascular defects. While evidence linking these drugs to birth defects in humans is not compelling, the reason may methodological rather than biological. Birth Defects Research 109:1358-1376, 2017.© 2017 Wiley Periodicals, Inc.

Personalized Therapy Against Preeclampsia by Replenishing Placental Protein 13 (PP13) Targeted to Patients With Impaired PP13 Molecule or Function

Hypertensive disorders affect about one third of all people aged 20 and above, and are treated with anti-hypertensive drugs. Preeclampsia (PE) is one form of such disorders that only develops during pregnancy. It affects ten million pregnant women globally and additionally causes fetal loss and major newborn disabilities. The syndrome's origin is multifactorial, and anti-hypertensive drugs are ineffective in treating it. Biomarkers are helpful for predict its development. Generic drugs, such as low dose aspirin, were proven effective in preventing preterm PE. However, it does not cure the majority of cases and many studies are underway for fighting PE with extended use of additional generic drugs, or through new drug development programs. This review focuses on placental protein 13 (PP13). This protein is only expressed in the placenta. Impaired PP13 DNA structure and/or its reduced mRNA expression leads to lower blood PP13 level that predict a higher risk of developing PE. Two polymorphic PP13 variants have been identified: (1) The promoter PP13 variant with an "A/A" genotype in the -98 position (versus "A/C" or "C/C"). Having the "A/A" genotype is coupled to lower PP13 expression, mainly during placental syncytiotrophoblast differentiation and, if associated with obesity and history of previous preeclampsia, it accurately predicts higher risk for developing the disorder. (2) A thymidine deletion at position 221 causes a frame shift in the open reading frame, and the formation of an early stop codon resulting in the formation of DelT221, a truncated variant of PP13. In pregnant rodents, both short- and long- term replenishment of PP13 causes reversible hypotension and vasodilation of uterine vessels. Long-term exposure is also accompanied by the development of larger placentas and newborns. Also, only w/t PP13 is capable of inducing leukocyte apoptosis, providing maternal immune tolerance to pregnancy. Based on published data, we propose a targeted PP13 therapy to fight PE, and consider the design and conduct of animal studies to explore this hypothesis. Accordingly, a new targeted therapy can be implemented in humans combining prediction and prevention.