Docosahexaenoic acid protects against lipopolysaccharide-induced fetal growth restriction via inducing the ubiquitination and degradation of NF-κB p65 in placental trophoblasts

Histological Features of Uterine Myometrial Dysfunction: Possible Involvement of Localized Inflammation

OBJECTIVE

The latest perspective suggests that elevated levels of inflammation and cytokines are implicated in atonic postpartum hemorrhage. Lipopolysaccharide (LPS) has been widely used to induce inflammation in animal models. Therefore, this study aimed to induce uterine inflammation using LPS to investigate whether local inflammation triggers dysfunction and atrophy in the myometrium, as well as the potential underlying molecular mechanisms involved.

METHODS

In vivo, an animal model was established by intraperitoneal injection of 300 μg/ kg LPS in rats on gestational day 21. Hematoxylin-eosin (H&E) staining and Masson staining were employed to determine morphological changes in the rat uterine smooth muscle. Enzyme-linked immunosorbent assay (ELISA) was used to detect inflammatory cytokines. Immunohistochemistry, tissue fluorescence, and Western blotting were conducted to assess the expression levels of the uterine contraction-related proteins Toll-like receptor 4 (TLR4) and the nuclear factor kappa-B (NF-κB) signaling pathway. In vitro, human uterine smooth muscle cells (HUtSMCs) were exposed to 2 μg/mL LPS to further elucidate the involvement of the TLR4/NF-κB signaling pathway in LPS-mediated inflammation.

RESULTS

In this study, LPS induced uterine myometrial dysfunction in rats, leading to a disorganized arrangement, a significant increase in collagen fiber deposition, and widespread infiltration of inflammatory cells. In both in vivo animal models and in vitro HUtSMCs, LPS elevated IL-6, IL-1β, and TNF-α levels while concurrently suppressing the expression of connexin 43 (Cx43) and oxytocin receptor (OXTR). Mechanistically, the LPS-treated group exhibited TLR4 activation, and the phosphorylation levels of p65 and IκBα were notably increased.

CONCLUSION

LPS triggered the TLR4/NF-κB signaling pathway, inducing an inflammatory response in the myometrium and leading to uterine myometrial dysfunction and uterine atony.

Gastrodin ameliorates neuroinflammation in Alzheimer's disease mice by inhibiting NF-κB signaling activation via PPARγ stimulation

AIM

We investigated the effects and targets of gastrodin (GAS) for improving cognitive ability in Alzheimer's disease (AD).

METHODS

The targets and mechanisms of GAS were analyzed by network pharmacology. Morris water and eight-arm radial mazes were used to detect the behaviors of 7-months-old APP/PS1 mice. The levels of IBA-1 and PPARγ were examined by histochemical staining, nerve cells were detected by Nissl staining, inflammatory cytokines were measured by ELISA, and protein expressions were monitored by Western blotting. The neurobehavioral effects of GAS on mice were detected after siRNA silencing of PPARγ. Microglia were cultured in vitro and Aβ1-42 was used to simulate the pathology of AD. After treatment with GAS, the levels of inflammatory cytokines and proteins were assayed.

RESULTS

Network pharmacological analysis revealed that PPARγ was the action target of GAS. By stimulating PPARγ, GAS inhibited NF-κB signaling activation and decreased neuroinflammation and microglial activation, thereby ameliorating the cognitive ability of AD mice. After silencing PPARγ, GAS could not further improve such cognitive ability. Cellular-level results demonstrated that GAS inhibited microglial injury, reduced tissue inflammation, and activated PPARγ.

CONCLUSIONS

GAS can regulate microglia-mediated inflammatory response by stimulating PPARγ and inhibiting NF-κB activation, representing a mechanism whereby it improves the cognitive behavior of AD.

Intrauterine Growth Restriction: Need to Improve Diagnostic Accuracy and Evidence for a Key Role of Oxidative Stress in Neonatal and Long-Term Sequelae

Intrauterine growth restriction (IUGR) and being small for gestational age (SGA) are two distinct conditions with different implications for short- and long-term child development. SGA is present if the estimated fetal or birth weight is below the tenth percentile. IUGR can be identified by additional abnormalities (pathological Doppler sonography, oligohydramnion, lack of growth in the interval, estimated weight below the third percentile) and can also be present in fetuses and neonates with weights above the tenth percentile. There is a need to differentiate between IUGR and SGA whenever possible, as IUGR in particular is associated with greater perinatal morbidity, prematurity and mortality, as well as an increased risk for diseases in later life. Recognizing fetuses and newborns being "at risk" in order to monitor them accordingly and deliver them in good time, as well as to provide adequate follow up care to ameliorate adverse sequelae is still challenging. This review article discusses approaches to differentiate IUGR from SGA and further increase diagnostic accuracy. Since adverse prenatal influences increase but individually optimized further child development decreases the risk of later diseases, we also discuss the need for interdisciplinary follow-up strategies during childhood. Moreover, we present current concepts of pathophysiology, with a focus on oxidative stress and consecutive inflammatory and metabolic changes as key molecular mechanisms of adverse sequelae, and look at future scientific opportunities and challenges. Most importantly, awareness needs to be raised that pre- and postnatal care of IUGR neonates should be regarded as a continuum.

Ubiquitin-specific protease 38 promotes inflammatory atrial fibrillation induced by pressure overload

AIMS

Atrial structural and electrical remodelling is a major reason for the initiation and perpetuation of atrial fibrillation (AF). Ubiquitin-specific protease 38 (USP38) is a deubiquitinating enzyme, but its function in the heart remains unknown. The aim of this study was to investigate the effect of USP38 in pressure overload-induced AF.

METHODS AND RESULTS

Cardiac-specific knockout USP38 and cardiac-specific transgenic USP38 mice and their corresponding control mice were used in this study. After 4 weeks with or without aortic banding (AB) surgery, atrial echocardiography, atrial histology, electrophysiological study, and molecular analysis were assessed. Ubiquitin-specific protease 38 knockout mice showed a remarkable improvement in vulnerability to AF, atrial weight and diameter, atrial fibrosis, and calcium-handling protein expression after AB surgery. Conversely, USP38 overexpression further increased susceptibility to AF by exacerbating atrial structural and electrical remodelling. Mechanistically, USP38 interacted with and deubiquitinated nuclear factor-kappa B (NF-κB), and USP38 overexpression increased the level of p-NF-κB in vivo and in vitro, accompanied by the upregulation of NOD-like receptor protein 3 (NLRP3) and inflammatory cytokines, suggesting that USP38 contributes to adverse effects by driving NF-κB/NLRP3-mediated inflammatory responses.

CONCLUSION

Overall, our study indicates that USP38 promotes pressure overload-induced AF through targeting NF-κB/NLRP3-mediated inflammatory responses.