Astaxanthin inhibiting oxidative stress damage of placental trophoblast cells in vitro

Temporal control in shell-core structured nanofilm for tracheal cartilage regeneration: synergistic optimization of anti-inflammation and chondrogenesis

Cartilage tissue engineering offers hope for tracheal cartilage defect repair. Establishing an anti-inflammatory microenvironment stands as a prerequisite for successful tracheal cartilage restoration, especially in immunocompetent animals. Hence, scaffolds inducing an anti-inflammatory response before chondrogenesis are crucial for effectively addressing tracheal cartilage defects. Herein, we develop a shell-core structured PLGA@ICA-GT@KGN nanofilm using poly(lactic-co-glycolic acid) (PLGA) and icariin (ICA, an anti-inflammatory drug) as the shell layer and gelatin (GT) and kartogenin (KGN, a chondrogenic factor) as the core via coaxial electrospinning technology. The resultant PLGA@ICA-GT@KGN nanofilm exhibited a characteristic fibrous structure and demonstrated high biocompatibility. Notably, it showcased sustained release characteristics, releasing ICA within the initial 0 to 15 days and gradually releasing KGN between 11 and 29 days. Subsequent in vitro analysis revealed the potent anti-inflammatory capabilities of the released ICA from the shell layer, while the KGN released from the core layer effectively induced chondrogenic differentiation of bone marrow stem cells (BMSCs). Following this, the synthesized PLGA@ICA-GT@KGN nanofilms were loaded with BMSCs and stacked layer by layer, adhering to a 'sandwich model' to form a composite sandwich construct. This construct was then utilized to repair circular tracheal defects in a rabbit model. The sequential release of ICA and KGN facilitated by the PLGA@ICA-GT@KGN nanofilm established an anti-inflammatory microenvironment before initiating chondrogenic induction, leading to effective tracheal cartilage restoration. This study underscores the significance of shell-core structured nanofilms in temporally regulating anti-inflammation and chondrogenesis. This approach offers a novel perspective for addressing tracheal cartilage defects, potentially revolutionizing their treatment methodologies.

Role of ferroptosis in pregnancy related diseases and its therapeutic potential

Ferroptosis is a form of regulated cell death characterized by iron overload, overwhelming lipid peroxidation, and disruption of antioxidant systems. Emerging evidence suggests that ferroptosis is associated with pregnancy related diseases, such as spontaneous abortion, pre-eclampsia, gestational diabetes mellitus, intrahepatic cholestasis of pregnancy, and spontaneous preterm birth. According to these findings, inhibiting ferroptosis might be a potential option to treat pregnancy related diseases. This review summarizes the mechanisms and advances of ferroptosis, the pathogenic role of ferroptosis in pregnancy related diseases and the potential medicines for its treatment.

Astaxanthin Alleviates Inflammatory Response in Neonatal Necrotizing Enterocolitis Rats by Regulating NOD2/TLR4 Pathway

Background

Necrotizing enterocolitis (NEC) is often associated with exaggerated activation of inflammatory response. Astaxanthin has been shown in studies to have a positive and advantageous effect on anti-inflammatory response. Hence, it is of great significance to study the protective effect of astaxanthin in NEC disease and its molecular mechanism.

Objective

The present study was to investigate whether astaxanthin attenuates NEC rats and to explore its potential mechanism. Material and Methods. Hematoxylin-eosin staining was used to observe the pathological change of the intestinal tissue in NEC rats. Subsequently, we determined the anti-oxidative stress, anti-apoptosis, and anti-inflammation in astaxanthin with enzyme-linked immunosorbent assay kits, TUNEL staining, western blot, and immunohistochemistry assay. Furthermore, we added nucleotide-binding oligomerization domain 2 (NOD2) inhibitor to certify the molecular pathway of the astaxanthin in NEC rats.

Results

Astaxanthin improved the pathological changes of the intestinal tissues. It restrained inflammation, oxidative stress, and protected cells from apoptosis in the intestinal tissue and serum of the NEC rats. Moreover, astaxanthin enhanced NOD2, whereas it suppressed toll-like receptor 4 (TLR4), nuclear factor-κB (NF-κB) pathway-related proteins. Apart from that, the NOD2 inhibitor offset the protective effect of the astaxanthin towards the NEC rats.

Conclusion

The present study indicated that astaxanthin alleviated oxidative stress, inflammatory response, and apoptosis in NEC rats by enhancing NOD2 and inhibiting TLR4 pathway.

Senescent endometrial stromal cells transmit reactive oxygen species to the trophoblast-like cells and impair spreading of blastocyst-like spheroids

Successful implantation requires a fine-tuned dialog between the invading embryo and the maternal endometrium. Recently, we discovered that premature senescence of endometrial stromal cells (EnSC) might mediate improper decidual transformation of endometrial tissue and impair endometrial-blastocyst interaction. Here, we show that senescent EnSC are characterized by elevated intracellular reactive oxygen species (ROS) levels that originate from mitochondrial dysfunction and insufficient antioxidant defense. Decidualization of senescent EnSC is defective and is accompanied by the elevated intracellular and mitochondrial ROS levels. Antioxidant defense during decidualization is significantly less efficient in senescent EnSC compared to healthy ones. Senescent EnSC secrete increased amounts of ROS into the extracellular space. Elevated ROS released by senescent EnSC shift the redox balance and induce DNA damage in the neighboring trophoblast-like cells. In an in vitro implantation model, we observed impaired spreading of blastocyst-like spheroids into a monolayer of decidualizing senescent EnSC, which could be compensated by pretreatment of the senescent cells with the antioxidant, Tempol. Hence, we propose a possible mechanism that might be responsible, at least in part, for the defective embryo implantation realized via ROS transmitting from senescent EnSC to trophoblast cells. Such transmission results in the accumulation of ROS and subsequent DNA damage in trophoblastic cells, which might lead to improper migration and invasion of an embryo. In light of these findings, the application of antioxidants prior to implantation might be a promising strategy to improve implantation efficiency.

Hydrogen sulfide against preeclampsia exposure-induced oxidative mitochondrial damage in HTR-8/SVneo cells

Extravillous trophoblast invasion disorder caused by oxidative stress is involved in the pathogenesis of preeclampsia (PE). In order to identify whether hydrogen sulfide (H2S) can prevent oxidative stress injury in extravillous trophoblasts. HTR-8/SVneo cells were detected by H2S inhibiting H2O2 induced oxidative mitochondrial damage. Reactive oxygen species (ROS) were detected, as well as malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD). JC-1 detected the potential of the mitochondrial membrane in this experiment. Then to detect the expression level of the apoptosis-inducing protein B-cell lymphoma-2 (Bcl-2) associated X protein (Bax), caspase 3, p53, p-p53, the apoptosis-inhibiting protein Bcl-2, PRAP, and the mitochondria fission protein Drp1, p-Drp1. CCK-8 assay, it was demonstrated that cell proliferation in the NaHS group was significantly higher than that in the Mod group, indicating that H2S may induce cell proliferation. Transwell assay elucidated that cell invasion in the NaHS group was recovered compared to the Mod group. ROS concentration no matter in cells or mitochondria was decreased by NaHS, which we could get from the comparison between the Mod group, PAG group, and NaHS group. The concentration of MDA was significantly lower in the NaHS group, and the concentration of SOD was extremely high in the NaHS group. Utilized JC-1 to detect mitochondrial membrane potential and found that cells from the NaHS group had a stable potential while cells from the Mod group and PAG group partly lost their potential, which could demonstrate that NaHS could maintain mitochondrial membrane potential. The western blot results revealed that p-Drp1 had a significant decline in the NaHS group, which means mitochondria fission was decreased in the NaHS group. The expression level of Bax and caspase 3 was significantly lower than in the Mod group and PAG group, and the expression level of Bcl-and PRAP was significantly higher in the NaHS group. That could prove that NaHS protect HTR-8/SVneo cell by inhibiting cell apoptosis. These promising results show that H2S elicits its effects on cell apoptosis by decreasing ROS concentration, maintaining mitochondrial membrane stability, and promoting apoptosis-inhibiting protein expression in cells.

Inhibition of ALKBH5-mediated m6 A modification of PPARG mRNA alleviates H/R-induced oxidative stress and apoptosis in placenta trophoblast

The alpha-ketoglutarate-dependent (ALKB) homolog 5 (ALKBH5), an m⁶ A demethylase, has been reported to be involved in the pathogenesis of preeclampsia (PE), but the exact mechanism requires further investigation. RT-qPCR or Western blotting were used to determine ALKBH5 and peroxisome proliferator-activated receptor gamma (PPARG) expression in placentas from PE patients and normal volunteers, as well as in HTR-8/SVneo cells treated with hypoxia/reoxygenation (H/R). Our results showed that the expression of ALKBH5 was significantly upregulated and PPARG was downregulated in preeclamptic placentas and H/R-treated cells. ALKBH5 interference reduced m⁶ A levels of PPARG mRNA, and increased PPARG mRNA stability and promoted PPARG translation level. In addition, ALKBH5 silencing increased the cell proliferation, migration, and vimentin protein level, and inhibited cell apoptosis, oxidative stress, and protein levels of endoglin (ENG) and E-cadherin in H/R-treated cells, whereas PPARG interference reversed these effects. Furthermore, PPARG repressed the H3K9me2 levels at activated leukocyte cell adhesion molecule (ALCAM) promoter region by increasing the expression and activity of lysine demethylase 3B (KDM3B). ALCAM inhibition reversed the effects of PPARG overexpression on H/R-treated cell functions. PKF115-584 suppressed the effects of ALKBH5 interference on the behaviors of H/R-treated cells. Finally, inhibition of ALKBH5 alleviates PE-like features in pregnant mice. Inhibition of ALKBH5 promotes KDM3B-mediated ALCAM demethylation by facilitating PPARG mRNA m⁶ A modification, and further activates the Wnt/β-catenin pathway, and in turn alleviates PE progression.

α-tocopherol prevents oxidative stress-induced proliferative dysfunction in first-trimester human placental (HTR-8/SVneo) cells

Extravillous trophoblasts (EVTs) are the main participants in the process of placentation, an early process critical for placental growth and function involving an adequate invasion and complete remodelling of the maternal spiral arteries during early pregnancy. An increase in oxidative stress during pregnancy is associated with the onset and progression of several pregnancy disorders, including preeclampsia and gestational diabetes mellitus and it also occurs due to exposure of pregnant women to some xenobiotics (eg. alcohol). This study aimed to investigate how oxidative stress affects EVTs, and the ability of several distinct antioxidant agents to prevent these changes. For this, we exposed HTR8/SVneo cells to tert-butylhydroperoxide (0.5 μM; 24 h), which was able to increase lipid peroxidation and protein carbonyl levels. Under these conditions, there was a decrease in proliferation rates, culture growth, migratory and angiogenic capacities and an increase in the apoptosis rates. The antiproliferative effect of TBH was supressed by simultaneous treatment of the cells with α-tocopherol, but other antioxidants (vitamin C, allopurinol, apocynin, N-acetylcysteine, quercetin and resveratrol) were ineffective. α-tocopherol was also able to abolish the effect of TBH on lipid peroxidation and protein carbonyl levels. Overall, our results show that oxidative stress interferes with EVT characteristics essential for the placentation process, which may contribute to the association between oxidative stress and pregnancy disorders. Our results also show that the nature of the in vitro model of oxidative stress-induction is an important determinant of the cellular consequences of oxidative stress and, therefore, of the efficacy of antioxidants.

Anti-inflammatory and Antioxidant Effects of Pyrroloquinoline Quinone in L-NAME-Induced Preeclampsia-Like Rat Model

Preeclampsia (PE) is a pregnancy complication commonly characterized by high blood pressure. Although it is generally believed that the placenta is the root cause of PE, the exact pathogenesis is unknown; consequently, there is no standard clinical treatment. Therefore, it is necessary to explore new therapeutic drugs. Several studies have reported that pyrroloquinoline quinone (PQQ) exhibits anti-inflammatory and antioxidative effects. The purpose of this study was to investigate the protective effect of PQQ diet supplementation on PE-like rat models. L-NAME induced PE-like model rats were intraperitonially administrated with PQQ. The results showed that PQQ significantly improved clinical manifestations and pregnancy outcomes of PE-like rats. The levels of related inflammatory and antioxidant markers were also significantly reversed. A mechanism study showed that PQQ may achieve the above therapeutic effects by inhibiting NF-κB and promoting Nrf2 antioxidant pathways. In conclusion, we showed the protective effect of PQQ on PE-like model rats, by improving anti-inflammation and antioxidation effect through the NF-κB-Nrf2 pathway.

Protection of Icariin Against Hydrogen Peroxide-Induced MC3T3-E1 Cell Oxidative Damage

Objective

The aim of the present study was to evaluate the potential protective mechanism of icariin against oxidative damage caused by hydrogen peroxide in MC3T3‐E1 cells.

Methods

MC3T3‐E1 cells were treated with different concentrations of icariin to explore the optimal dose of icariin. MC3T3‐E1 cells were divided into groups treated with various concentrations of hydrogen peroxide (H₂O₂; 0, 0.1, 0.2, 0.5, 1, and 2 mM) for 24 h to induce oxidative damage and cell viability was assessed by Cell Counting Kit‐8 (CCK‐8) assay. Then, cells were divided into five groups: control, H₂O₂ (0.2 mM), icariin (0.1 μM) and H₂O₂ (0.2 mM), + icariin (0.1 μM). Cell viability was detected by CCK‐8 assay. In addition, the content of glutathione and superoxide dismutase and the activity level of malondialdehyde in these treatment groups were determined. Alkaline phosphatase (ALP) and alizarin red S (ARS) staining were also performed to measure the early and late osteogenesis, respectively. Protein expression of β‐catenin and cyclin D1 was measured by western blot assay. Then, we used an antagonist of Wnt/β‐catenin signaling pathway (DKK‐1) and western blot analysis to further explore potential mechanism.

Results

After 24 h of exposure to 0.2 mM H₂O₂, the viability of MC3T3‐E1 cells was significantly decreased compared to that of the control cells. We first found that icariin can promote cell proliferation of MC3T3‐E1 cells in a dose‐dependent manner, with the dosage 0.1 μM showing the best pro‐proliferative effect. Furthermore, icariin could promote the protein expression of OSX and RUNX2. The results showed that icariin can reverse the inhibitory osteogenic effects of MC3T3‐E1 caused by H₂O₂. In addition, icariin could increase the Wnt‐signaling related proteins. The results showed that MC3T3‐E1 cells in the H₂O₂ (0.2 mM) + icariin (0.1 μM) + Wnt‐signaling antagonist (DKK‐1) group had weaker ALP and ARS staining compared with that observed in the control and H₂O₂ (0.2 mM) + icariin (0.1 μM) groups. The ALP activity and calcium content were decreased in the 0.2 mM H₂O₂ + 0.1 μM icariin + DKK‐1 group compared to that observed in the 0.2 mM H₂O₂ + 0.1 μM icariin group.

Conclusion

The results showed that icariin can increase the viability of MC3T3‐E1 cells, reverse the oxidative stress induced by H₂O₂ and protect MC3T3‐E1 cells against H₂O₂‐induced inhibition of osteogenic differentiation, which may occur through the Wnt/β‐catenin signaling pathway.