USP22 regulates the formation and function of placental vasculature during the development of fetal growth restriction

Regulation of placental development and function by ubiquitination

The proper distribution of nutrients and metabolites between the mother and fetus is one important factor for successful pregnancy. As a bridge, the placenta plays a key role in sensing the nutritional needs of the fetus, coordinating the maternal nutrition supply, and enhancing its nutritional transport capabilities. Imperfect placental development can lead to pregnancy-related disorders such as preeclampsia, recurrent miscarriage, and/or fetal growth restriction, posing risks to both mother and child in the short and long term. However, current understanding of the human placenta remains as a "black box", and its developmental control mechanisms for adaptive pregnant regulation still needs to be elucidated. As one form of post-translational modification (PTM), ubiquitination plays an important role in regulating cellular functions and is regarded as a valuable drug target. Particularly, ubiquitination related to placenta development has been discovered in recent years. Placental development processes closely associated with pregnant complications, such as blastocyst implantation, syncytiotrophoblast cell differentiation, and immune barrier maintenance, have been reported to be affected by ubiquitination. However, the diagnosis and intervention of pregnancy diseases also urgently need to be improved. Thus, aiming to comprehensive summarize and further exploring the molecular mechanism, target and regulatory mechanism of pregnancy complications, we have herein reviewed genes and pathways regulating pregnancy progress and diseases and focusing on ubiquitin-related physiological process in placenta.

The central role of creatine and polyamines in fetal growth restriction

Placental insufficiency often correlates with fetal growth restriction (FGR), a condition that has both short- and long-term effects on the health of the newborn. In our study, we analyzed placental tissue from infants with FGR and from infants classified as small for gestational age (SGA) or appropriate for gestational age (AGA), performing comprehensive analyses that included transcriptomics and metabolomics. By examining villus tissue biopsies and 3D trophoblast organoids, we identified significant metabolic changes in placentas associated with FGR. These changes include adaptations to reduced oxygen levels and modifications in arginine metabolism, particularly within the polyamine and creatine phosphate synthesis pathways. Specifically, we found that placentas with FGR utilize arginine to produce phosphocreatine, a crucial energy reservoir for ATP production that is essential for maintaining trophoblast function. In addition, we found polyamine insufficiency in FGR placentas due to increased SAT1 expression. SAT1 facilitates the acetylation and subsequent elimination of spermine and spermidine from trophoblasts, resulting in a deficit of polyamines that cannot be compensated by arginine or polyamine supplementation alone, unless SAT1 expression is suppressed. Our study contributes significantly to the understanding of metabolic adaptations associated with placental dysfunction and provides valuable insights into potential therapeutic opportunities for the future.

To boldly go where no microRNAs have gone before: spaceflight impact on risk for small-for-gestational-age infants

In the era of renewed space exploration, comprehending the effects of the space environment on human health, particularly for deep space missions, is crucial. While extensive research exists on the impacts of spaceflight, there is a gap regarding female reproductive risks. We hypothesize that space stressors could have enduring effects on female health, potentially increasing risks for future pregnancies upon return to Earth, particularly related to small-for-gestational-age (SGA) fetuses. To address this, we identify a shared microRNA (miRNA) signature between SGA and the space environment, conserved across humans and mice. These miRNAs target genes and pathways relevant to diseases and development. Employing a machine learning approach, we identify potential FDA-approved drugs to mitigate these risks, including estrogen and progesterone receptor antagonists, vitamin D receptor antagonists, and DNA polymerase inhibitors. This study underscores potential pregnancy-related health risks for female astronauts and proposes pharmaceutical interventions to counteract the impact of space travel on female health.

Overexpression of USP22 ameliorates LPS-induced endometrial stromal cells inflammation and modulates cells decidualization by inhibiting ferroptosis

Endometritis and the failure of decidualization of the endometrium are important factors contributing to the increased incidence of abortion. USP22 is associated with various inflammatory diseases and has been shown to be involved in endometrial decidualization in mice. This study aims to investigate whether USP22 is involved in the regulation of inflammatory response and decidualization in human endometrial stromal cells (hESCs). In this study, lipopolysaccharide (LPS) was used to induce inflammation in hESCs, and MPA combined with cAMP was used to induce decidualization of hESCs. USP22 overexpression vector was constructed to study the role of USP22 in endometritis. The results showed that the USP22 protein and mRNA levels were decreased in LPS-induced hESCs. LPS induction increased the levels of TNF-α, IL-1β, and IL-6, as well as the expression of iNOS and COX2 proteins in hESCs. In the LPS group, the levels of F-actin, PRL, IGFBP1, SLC7A11, and GPX4 proteins decreased, while the levels of lipid peroxidation and total iron content increased. Additionally, the levels of ACSL4 and TFR1 proteins were up-regulated. Overexpression of USP22 reversed LPS-induced cellular inflammation, attenuated decidualization, and inhibited ferroptosis. However, the use of ferroptosis inducers diminished the regulatory effects of USP22 on inflammatory responses and decidualization. In summary, these suggested that USP22 reduces the LPS-induced inflammatory response and regulates the decidualization of hESCs, and possibly involving ferroptosis.

USP22 knockdown protects against cerebral ischemia/reperfusion injury via destabilizing PTEN protein and activating the mTOR/TFEB pathway

Ubiquitin-specific protease 22 (USP22) expression was reported to be increased in response to ischemic brain damage, but the biological role and underlying mechanism remain little understood. USP22 shRNA was intravenously injected into the mouse brain, and then a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model was constructed, and the infarct volume, neurobehavioral deficit score, cell apoptosis, oxidative stress, and autophagy in vivo were evaluated. Oxygen-glucose deprivation/reperfusion (OGD/R) treated pheochromocytoma-12 (PC12) cells were used as an in vitro model of ischemia/reperfusion. The effects of USP22 on proliferation, apoptosis, oxidative stress, and autophagy were explored by CCK-8, flow cytometry, ELISA, and Western blot assays. The relationship between USP22 and the phosphatase and tensin homolog (PTEN) was measured by Co-IP and Western blot assays. Both USP22 and PTEN were highly expressed in MCAO/R mouse brain tissues and OGD/R-induced PC12 cells. In vitro, USP22 knockdown strongly improved OGD/R-mediated changes in cell viability, apoptosis, oxidative stress, and lactate dehydrogenase (LDH) production in PC12 cells. USP22 bound to PTEN and stabilized PTEN expression by decreasing its ubiquitination. PTEN overexpression reversed the promoting effect of USP22 knockdown on cell viability and the inhibitory effects of USP22 knockdown on apoptosis, oxidative stress, and LDH release rate in PC12 cells subjected to OGD/R. PTEN silencing elevated the protein levels of p62, p-mTOR, TFEB, and LAMP1 and reduced the protein levels of LC3-II/LC3-I. USP22 expression levels were negatively correlated with mTOR expression levels, and USP22-shRNA-mediated expression of p62, p-mTOR, TFEB, and LAMP1 was reversed by rapamycin, an inhibitor of mTOR. In vivo, USP22 silencing significantly alleviated infarct volume, neurobehavioral impairments, cell apoptosis, oxidative stress, and autophagy in MCAO/R mice. USP22 knockdown exerts neuroprotective effects in cerebral ischemia/reperfusion injury by downregulating PTEN and activating the mTOR/TFEB pathway.

The Role of Syncytin in Placental Angiogenesis and Fetal Growth

Background: Syncytin, a retroviral envelope protein, is specifically expressed on trophoblast cells and mediates formation of the syncytiotrophoblast through fusogenic activity. Decreased expression of Syncytin was found in fetal growth restriction placentas. Results: By generating an inducible knockout of the syncytin-a gene in mice, we show a specific disruption of placental angiogenesis with abnormal formation of two syncytiotrophoblast layers. Consistent with the defects observed in vivo, conditioned medium collected from trophoblast cells, following Syncytin-1 knockdown, contains lower expression of vascular endothelial growth factor and placental growth factor, and higher levels of soluble fms-like protein kinase-1 in BeWo and HTR-8/SVneo cells which related with suppressed PI3K/Akt/mTOR pathway, and is reduced in ability to induce tube formation by HUVECs. Conclusion: Syncytin participates in angiogenesis during placental development was first identified both in vivo and in vitro. Here, we give a new sight on understanding syncytin and pathophysiology of placenta related disease such as fetal growth restriction.

Correlation between Parturients' Uterine Artery Blood Flow Spectra in the First and Second Trimesters of Pregnancy and Fetal Growth Restriction

Objective

To explore the correlation between parturients' uterine artery blood flow spectra in the first and second trimesters of pregnancy and fetal growth restriction (FGR).

Methods

The data of parturients treated in our hospital from February 2018 to February 2020 were retrospectively analyzed, 50 parturients with FGR were selected as the FGR group, and other 50 healthy cases were selected as the control group. In the first trimester (11-12 weeks of gestation) and the second trimester of pregnancy (13–24 weeks of gestation), the parturients of the two groups accepted the color Doppler ultrasonography (CDS), their hemodynamics indicators of uterine artery were recorded, and the correlation between their uterine artery blood flow spectra in the two periods and FGR was analyzed with the Receiver Operating Characteristic (ROC) curve.

Results

No statistical differences in the parturients' general information including age, gestational weeks, gravidity, and parity between the two groups were observed (P > 0.05); the newborn's body weight, Apgar scores, number of preterm infants, and the number of infants transferring to the neonatal intensive care unit (NICU) were significantly different between the two groups (P < 0.05); in the first and second trimesters of pregnancy, the uterine artery pulsatility index (UtA-PI), uterine artery resistance index (UtA-RI), maximal systolic flow velocity, and systolic/diastolic (UtA-S/D) ratio were significantly higher in the FGR group than in the control group (P < 0.05), and the time-averaged maximal velocity (TAMX) was significantly lower in the FGR group than in the control group (P < 0.001); in early pregnancy, the incidence of early diastolic notch at bilateral uterine arteries between the two groups was not significantly different (P > 0.05), and the unilateral and total incidence in the first trimester as well as the unilateral, bilateral, and total incidence in the second trimester were significantly higher in the FGR group than in the control group (P < 0.05); in the first trimester, the sensitivity of detecting FGR with a uterine artery blood flow spectrum was 0.820, AUC (95% CI) = 0.840 (0.757–0.923), and in the second trimester, it was 0.860, AUC (95% CI) = 0.900 (0.832–0.968).

Conclusion

There is a correlation between uterine artery blood flow spectra in the first and second trimesters of pregnancy and FGR, and the sensitivity of spectrum in the first trimester is higher than that in the second trimester, presenting a better clinical application value.