Effect of SOCS3 on apoptosis of human trophoblasts via adjustment of the JAK2/STAT3 signaling pathway in preterm birth

Novel insights into dimethylsulfoniopropionate cleavage by deep subseafloor fungi

Dimethylsulfoniopropionate (DMSP), a key organic sulfur compound in marine and subseafloor sediments, is degraded by phytoplankton and bacteria, resulting in the release of the climate-active volatile gas dimethylsulfide (DMS). However, it remains unclear if dominant eukaryotic fungi in subseafloor sediments possess specific abilities and metabolic mechanisms for DMSP degradation and DMS formation. Our study provides the first evidence that fungi from coal-bearing sediments ∼2 km below the seafloor, such as Aspergillus spp., Chaetomium globosum, Cladosporium sphaerospermum, and Penicillium funiculosum, can degrade DMSP and produce DMS. In Aspergillus sydowii 29R-4-F02, which exhibited the highest DMSP-dependent DMS production rate (16.95 pmol/μg protein/min), two DMSP lyase genes, dddP and dddW, were identified. Remarkably, the dddW gene, previously observed only in bacteria, was found to be crucial for fungal DMSP cleavage. These findings not only extend the list of fungi capable of degrading DMSP, but also enhance our understanding of DMSP lyase diversity and the role of fungi in DMSP decomposition in subseafloor sedimentary ecosystems.

Flavonoids with Anti-Angiogenesis Function in Cancer

The formation of new blood vessels, known as angiogenesis, significantly impacts the development of multiple types of cancer. Consequently, researchers have focused on targeting this process to prevent and treat numerous disorders. However, most existing anti-angiogenic treatments rely on synthetic compounds and humanized monoclonal antibodies, often expensive or toxic, restricting patient access to these therapies. Hence, the pursuit of discovering new, affordable, less toxic, and efficient anti-angiogenic compounds is imperative. Numerous studies propose that natural plant-derived products exhibit these sought-after characteristics. The objective of this review is to delve into the anti-angiogenic properties exhibited by naturally derived flavonoids from plants, along with their underlying molecular mechanisms of action. Additionally, we summarize the structure, classification, and the relationship between flavonoids with their signaling pathways in plants as anti-angiogenic agents, including main HIF-1α/VEGF/VEGFR2/PI3K/AKT, Wnt/β-catenin, JNK1/STAT3, and MAPK/AP-1 pathways. Nonetheless, further research and innovative approaches are required to enhance their bioavailability for clinical application.

Exosomal microRNAs in regulation of tumor cells resistance to apoptosis

Exosomes are a type of extracellular vesicle that contains bioactive molecules that can be secreted by most cells. Nevertheless, the content of these cells differs depending on the cell from which they originate. The exosome plays a crucial role in modulating intercellular communication by conveying molecular messages to neighboring or distant cells. Cancer-derived exosomes can transfer several types of molecules into the tumor microenvironment, including high levels of microRNA (miRNA). These miRNAs significantly affect cell proliferation, angiogenesis, apoptosis resistance, metastasis, and immune evasion. Increasing evidence indicates that exosomal miRNAs (exomiRs) are crucial to regulating cancer resistance to apoptosis. In cancer cells, exomiRs orchestrate communication channels between them and their surrounding microenvironment, modulating gene expression and controlling apoptosis signaling pathways. This review presents an outline of present-day knowledge of the mechanisms that affect target cells and drive cancer resistance to apoptosis. Also, our study looks at the regulatory role of exomiRs in mediating intercellular communication between tumor cells and surrounding microenvironmental cells, specifically stromal and immune cells, to evade therapy-induced apoptosis.

Research progress on the STAT signaling pathway in pregnancy and pregnancy-associated disorders

Signal transducer and activator of transcription (STAT) proteins, pivotal regulators of signaling cascades, undergo activation in response to the stimulation of cytokines and growth factors, and participate in biological processes, including inflammation, immune responses, cell proliferation, and differentiation. During the process of pregnancy, STAT signaling is involved in regulating embryonic implantation, endometrial decidualization, and establishing and maintaining maternal-fetal immune tolerance. Increasing evidence suggests that aberrant STAT signaling contributes to the occurrence and development of pregnancy disorders, including repeated implantation failure (RIF), preeclampsia (PE), recurrent spontaneous abortion (RSA), preterm birth (PTB) and gestational diabetes mellitus (GDM). Elucidating the molecular mechanisms of the STAT signaling pathway holds promise for further understanding the establishment and maintenance of normal pregnancy, and thereby providing potent targets and strategic avenues for the prevention and management of ailments associated with pregnancy. In this review, we summarized the roles of the STAT signaling pathway and its related regulatory function in embryonic implantation, endometrial decidualization, and maternal-fetal immune tolerance. In conclusion, in-depth research on the mechanism of the STAT signaling pathway not only enhances our understanding of normal pregnancy processes but also offers STAT-based therapeutic approaches to protect women from the burden of pregnancy-related disorders.

Anaerobic production and biosynthesis mechanism of exopolysaccharides in Schizophyllum commune 20R-7-F01

Exopolysaccharides (EPS) produced by microorganisms play a vital role in physiological and ecological processes. However, the mechanisms of EPS synthesis and release in anaerobic environments remain poorly understood. Here, we provide the first evidence of anaerobic EPS synthesis by the fungus Schizophyllum commune 20R-7-F01, isolated from coal-bearing sediments ~2.0 km below the seafloor. Under anaerobic conditions, the fungus exhibited significantly higher specific EPS production (1.57 times) than under aerobic conditions. Transcriptomic analysis revealed 2057 differentially expressed genes (DEGs) in the strain cultured anaerobically for 7 days compared to aerobically. Among these genes, 642 were significantly upregulated, while 1415 were significantly downregulated, mainly associated with carbon metabolism pathways. Genes involved in glycolysis and EPS synthesis, including hexokinase (HK), phosphoglucomutase (PGM), and (1 → 3)-β-glucan synthase (GLS), were significantly upregulated, while those related to the TCA cycle, respiratory chain, and pentose phosphate pathway were downregulated under anaerobic conditions. These findings highlight the oxygen-dependent regulation of EPS synthesis and suggest that EPS may serve as a key mechanism for fungal adaptation to anaerobic environments.

A genome-wide and candidate gene association study of preterm birth in Korean pregnant women

Preterm birth (PTB) refers to delivery before 37 weeks of gestation. Premature neonates exhibit higher neonatal morbidity and mortality rates than term neonates; therefore, it is crucial to predict and prevent PTB. Advancements enable the prediction and prevention of PTB using genetic approaches, especially by investigating its correlation with single nucleotide polymorphisms (SNPs). We aimed to identify impactive and relevant SNPs for the prediction of PTB via whole-genome sequencing analyses of the blood of 31 pregnant women with PTB (n = 13) and term birth (n = 18) who visited the Ewha Womans University Mokdong Hospital from November 1, 2018 to February 29, 2020. A genome-wide association study was performed using PLINK 1.9 software and 256 SNPs were selected and traced through protein-protein interactions. Moreover, a validation study by genotyping was performed on 60 other participants (preterm birth, n = 30; term birth, n = 30) for 25 SNPs related to ion channel binding and receptor complex pathways. Odds ratios were calculated using additive, dominant, and recessive genetic models. The risk of PTB in women with the AG allele of rs2485579 (gene name: RYR2) was significantly 4.82-fold increase, and the risk of PTB in women with the AG allele of rs7903957 (gene name: TBX5) was significantly 0.25-fold reduce. Our results suggest that rs2485579 (in RYR2) can be a genetic marker of PTB, which is considered through the association with abnormal cytoplasmic Ca2+ concentration and dysfunctional uterine contraction due to differences of RYR2 in the sarcoplasmic reticulum.

Therapeutic potential of icariin in rats with letrozole and high-fat diet-induced polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is characterized by reproductive, endocrine, and metabolic disorders. Icariin has been shown to regulate endocrine and metabolic imbalances. This study aimed to determine the therapeutic effect and pharmacological mechanism of icariin in PCOS rats. Rats were fed a high-fat diet and gavaged with letrozole to induce PCOS. Thirty-six female rats were randomly divided into four groups: control, model, low-dose, and high-dose icariin. After 30 days of treatment, we evaluated the therapeutic effects on weight and diet, sex hormone levels, ovarian morphology, estrous cycle, inflammatory factors, and indicators of glucolipid metabolism. Combined with the ovarian transcriptome, we verified the key markers of apoptosis and the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathway by RT-qPCR for mRNA level, western blot, and immunohistochemistry for protein expression. Icariin significantly improved ovarian function and reproductive endocrine disorders by regulating sex hormones, restoring the estrous cycle, and reducing ovarian morphological damage in PCOS rats. Icariin-treated rats had lower weight gain and reduced triglycerides, fasting insulin, HOMA-IR, TNF-α, and interleukin-6 with higher high-density lipoprotein cholesterol levels than PCOS rats. TUNEL staining showed icariin improved apoptosis in the ovaries. This was supported by an increase in Bcl2 and a decrease in Bad and Bax. Icariin decreased the ratios of p-JAK2/JAK2, p-STAT1/STAT1, p-STAT3/STAT3, and p-STAT5a/STAT5a, decreased IL-6, gp130 expression, and increased cytokine-inducible SH2-containing protein (CISH) and suppressor of cytokine signaling 1 (SOCS1) expression. The pharmacological mechanism may be related to the reduction in ovarian apoptosis and inhibition of the IL-6/gp130/JAK2/STATs pathway.

JAK2 inhibitor ameliorates the progression of experimental autoimmune myasthenia gravis and balances Th17/Treg cells via regulating the JAK2/STAT3-AKT/mTOR signaling pathway

BACKGROUND

An imbalance in Th17/regulatory T (Treg) cells is the major pathogenic mechanism underlying myasthenia gravis (MG). JAK2 inhibitors selectively inhibit JAK2 and reduce inflammatory responses. However, there have been no studies examining the therapeutic effects of JAK2 inhibitors in the context of MG.

METHODS

Here, an experimental autoimmune MG (EAMG) rat model was established to explore the therapeutic effect of JAK2 inhibitors on EAMG rats immunized with the AChR α-subunit (97-116 peptide). A JAK2 inhibitor was administered to EAMG rats both in vivo and in vitro. The following experimental methods were used to evaluate the effects of JAK2 inhibitors. The behavioral scores and body weights of the rats were assessed on alternate days. Serum anti-AChR (97-116) IgG and cytokine levels were detected using ELISA. CD4⁺ T cell subsets and related transcription factors in mononuclear cells were detected using flow cytometry and qPCR, respectively. The expression levels of protein molecules in the signaling pathway were detected by western blotting, and the neuromuscular junctions were observed using immunofluorescence.

RESULTS

The results revealed that JAK2 inhibitors could regulate Th17/Treg balance in vivo and in vitro. JAK2 inhibitors reduced the immune response in EAMG rats (including reducing pro-inflammatory cytokines and postsynaptic membrane complement deposition), improved clinical symptoms, and increased AChR aggregation in the postsynaptic membrane. Meanwhile, this study demonstrated that JAK2 inhibitor treatment suppressed the phosphorylation of JAK2/STAT3 and AKT/mTOR pathways and decreased the expression level of the IL-23 receptor.

CONCLUSIONS

This study reveals that there is crosstalk between the JAK2/STAT3 and AKT/mTOR pathways in EAMG rats. JAK2 inhibitors can ameliorate EAMG by regulating Th17/Treg balance by inhibiting both signaling pathways. Our study provides new potential therapeutic targets for MG immunotherapy.

JAK-STAT Signaling Pathway in Non-Infectious Uveitis

Non-infectious uveitis (NIU) refers to various intraocular inflammatory disorders responsible for severe visual loss. Cytokines participate in the regulation of ocular homeostasis and NIU pathological processes. Cytokine receptors transmit signals by activating Janus kinase (JAK) and signal transducer and activator of transcription (STAT) proteins. Increasing evidence from human NIU and experimental models reveals the involvement of the JAK-STAT signaling pathway in NIU pathogenesis. Several small-molecule drugs that potentially inhibit multiple cytokine-dependent pathways are under investigation for treating autoimmune diseases, implicating possible applications for NIU treatment. This review summarizes the current understanding of the diverse roles of the JAK-STAT signaling pathway in ocular homeostasis and NIU pathology, providing a rationale for targeting JAKs and STATs for NIU treatment. Moreover, available evidence for the safety and efficacy of JAK inhibitors for refractory uveitis and potential approaches for treatment optimization are discussed.