Activation and function of the MAPKs and their substrates, the MAPK-activated protein kinases. Microbiol Mol Biol Rev. 2011;75:50-83. [PMID: 21372320 DOI: 10.1128/mmbr.00031-10]

CcPTGS2a-like gene-mediated NF-κB/ERK signaling regulation in the common carp (Cyprinus carpio)

Prostaglandin-endoperoxide synthase 2 (PTGS2), a common biological macromolecule, is pivotal for innate immunity and pathogen recognition. In this study, we identified and characterized a CcPTGS2a-like gene in the common carp (Cyprinus carpio) with an open reading frame (ORF) of 1821 bp and epidermal growth factor and peroxidase domains. Our multiple sequence analysis revealed high homology between the amino acid sequence of CcPTGS2a-like and those of its homologs in other fish. CcPTGS2a-like mRNA and protein expressions were significantly upregulated in the spleen, head kidney, liver, and gill tissues upon exposure to Aeromonas hydrophila stimulation. CcPTGS2a-like protein recognized the conserved bacterial surface components and exhibited detectable bacterial binding activity. CcPTGS2a-like overexpression before exposure to A. hydrophila notably enhanced the survival rate of common carp, concomitant with decreased bacterial burden. The NF-κB/ERK signaling pathway initiated the immune response in common carp upon infection with A. hydrophila. CcPTGS2a-like overexpression or interference in the head kidney and Epithelioma papulosum cyprinid cells could modulate the p-NF-κB (p-p-65), p-IκBα, and p-ERK1/2 levels as well as the IL-1β and IL-6 mRNA expression. These results indicated potential CcPTGS2a-like involvement in the immune response of the common carp to bacterial infections through the NF-κB/ERK signaling pathway.

A shift in chromatin binding of phosphorylated p38 precedes transcriptional changes upon oxidative stress

P38 mitogen-activated protein kinases are key in the regulation of the cellular response to stressors. P38 is known to regulate transcription, mRNA processing, stability, and translation. The transcriptional changes mediated by phosphorylated p38 (P-p38) in response to extracellular stimuli have been thoroughly analyzed in many tissues and organisms. However, the genomic localization of chromatin-associated P-p38 remains poorly understood. Here, we analyze the chromatin binding of activated P-p38 and its role in the response to reactive oxygen species (ROS) in Drosophila S2 cells. We found that P-p38 is already bound to chromatin in basal conditions. After ROS exposure, chromatin-associated P-p38 relocates towards genes involved in the recovery process. Our findings highlight the role of P-p38 dynamic chromatin binding in orchestrating gene expression responses to oxidative stress.

TG2 participates in pulmonary vascular remodelling by regulating the senescence of pulmonary artery smooth muscle cells

Pulmonary hypertension (PH) is a severe cardiovascular disease characterised by pulmonary vascular remodelling. The pivotal role of cellular senescence in vascular remodelling has been acknowledged. Transglutaminase type 2 (TG2), a calcium-dependent enzyme, is intricately linked to both cellular senescence and PH. However, the precise mechanisms underlying the involvement of TG2 in PH remain unclear. In this study, we explored the expression of TG2 and the cellular senescence marker p16INK4a in the pulmonary vasculature of mice with PH induced by hypoxia combined with SU5416. Our findings revealed upregulation of both TG2 and p16INK4a expression in the pulmonary vasculature of PH mice. Additionally, a notable increase in TG2 expression was observed in senescent pulmonary artery smooth muscle cells (PASMC). To delve deeper, we employed proteomic sequencing to reveal seven genes associated with cellular senescence, with a subsequent focus on MAPK14. Our investigation revealed that TG2 regulates senescence in PASMC by modulating the phosphorylation levels of MAPK14. Additionally, in the context of hypoxia combined with SU5416, our observations revealed a noteworthy reduction in both pulmonary vascular remodelling and senescent manifestations in smooth muscle-specific TG2 knockout mice compared with their wild-type counterparts. In summary, our findings indicate that TG2 deficiency lowers the senescence levels of PASMC by inhibiting the activity of MAPK14. This inhibition of senescence in the pulmonary vasculature of PH mice helps to decelerate the progression of pulmonary vascular remodelling and consequently hinders the onset and development of PH.

Recent developments in receptor tyrosine kinase inhibitors: A promising mainstay in targeted cancer therapy

During the past two decades, significant advances have been made in the discovery and development of targeted inhibitors aimed at improving the survival rates of cancer patients. Among the multitude of potential therapeutic targets identified thus far, Receptor Tyrosine Kinases (RTKs) are of particular importance. Dysregulation of RTKs has been implicated in numerous human diseases, particularly cancer, where aberrant signaling pathways contribute to disease progression. RTKs have a profound impact on intra and intercellular communication, and they also facilitate post-translational modifications, notably phosphorylation, which intricately regulates a multitude of cellular processes. Prolonged phosphorylation or the disruption of kinase regulation may lead to significant alterations in cell signaling. The emergence of small molecule kinase inhibitors has revolutionized cancer therapy by offering a targeted and strategic approach that surpasses the efficacy of traditional chemotherapeutic drugs. Over the last two decades, a plethora of targeted inhibitors have been identified or engineered and have undergone clinical evaluation to enhance the survival rates of cancer patients. In this review, we have compared the expression of different RTKs, including Met, KDR/VEGFR2, EGFR, BRAF, BCR, and ALK across different cancer types in TCGA samples. Additionally, we have summarized the recent development of small molecule inhibitors and their potential in treating various malignancies. Lastly, we have discussed the mechanisms of acquired therapeutic resistance with a focus on kinase inhibitors in EGFR mutant and ALK-rearranged non-small cell lung cancer and BCR-ABL positive chronic myeloid leukemia.

Pogostemon cablin essential oil as feed additive promotes the repair of the rumen epithelial barrier in heat-stressed beef cattle

Pogostemon cablin essential oil (PEO), extracted from P. cablin, has anti-oxidant, anti-inflammatory, and anti-stress properties, as well as the ability to improve gastrointestinal digestion. This study aims to evaluate the effects of PEO on the performance, rumen epithelial morphology, and barrier function in heat-stressed beef cattle. Thirty-six male Jingjiang cattle at 18 months old were randomly assigned into four groups and fed a diet containing PEO at 0 (control), 50, 100, or 150 mg/kg in the feed concentrate (n = 9). All experimental cattle were fed under high temperature and humidity in summer for 60 days. The results indicated that 50 mg/kg of PEO treatment enhanced the average daily gain of beef cattle compared with the control group (P = 0.032). All PEO treatments reduced the diamine oxidase activity (P = 0.004) and malondialdehyde content (P = 0.008) in serum. In addition, the content of 70 kDa heat shock protein in the 100 mg/kg group was increased, and the activity of glutathione peroxidase and total antioxidant capacity in both 100 mg/kg and 150 mg/kg groups were enhanced compared to the control group (P < 0.05). More importantly, PEO treatment with 50 mg/kg enhanced the mRNA relative expressions of occludin in ruminal epithelia but decreased the mRNA relative expressions of c-Jun N-terminal kinase, P38 mitogen-activated protein kinases, caspase-3, Beclin1 (P < 0.05), and extremely significant declined the mRNA relative expressions of extracellular regulated protein kinases and ubiquitin-binding protein in contrast to the control group (P < 0.01). These findings indicated that dietary PEO supplementation might be favorable to improve growth performance and repairing damaged rumen epithelium of heat-stressed cattle by down-regulating the mitogen-activated protein kinase signaling pathway.

Regulatory Mechanisms of Natural Active Ingredients and Compounds on Keratinocytes and Fibroblasts in Mitigating Skin Photoaging

Background

The mechanism underlying skin photoaging remains elusive because of the intricate cellular and molecular changes that contribute to this phenomenon, which have yet to be elucidated. In photoaging, the roles of keratinocytes and fibroblasts are vital for maintaining skin structure and elasticity. But these cells can get photo-induced damage during photoaging, causing skin morphological changes. Recently, the function of natural active ingredients in treating and preventing photoaging has drawn more attention, with researches often focusing on keratinocytes and fibroblasts.

Methods

We searched for studies published from 2007 to January 2024 in the Web of Science, PubMed, and ScienceDirect databases through the following keywords: natural plant, natural plant products or phytochemicals, traditional Chinese Medicine or Chinese herbal, plant extracts, solar skin aging, skin photoaging, and skin wrinkling. This review conducted the accordance of Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

Results

In total, 87 researches were included in this review (Figure 1). In keratinocytes, natural compounds may primarily regulate signal pathways such as the NF-κB, MAPK, PI3K/AKT, and Nrf2/ARE pathways, reducing inflammation and cellular damage, thus slowing skin photoaging. Additionally, in fibroblasts, natural active ingredients primarily promote the TGF-β pathway, inhibit MMPs activity, and enhance collagen synthesis while potentially modulating the mTOR pathway, thereby protecting the dermal collagen network and reducing wrinkle formation. Several trials showed that natural compounds that regulate keratinocytes and fibroblasts responses have significant and safe therapeutic effects.

Conclusion

The demand for natural product-based ingredients in sunscreen formulations is rising. Natural compounds show promising anti-photoaging effects by targeting cellular pathways in keratinocytes and fibroblasts, providing potential therapeutic strategies. However, comprehensive clinical studies are needed to verify their efficacy and safety in mitigating photoaging, which should use advanced pharmacological methods to uncover the complex anti-photoaging mechanisms of natural compounds.

Prohibitin 2 confers NADPH oxidase 1-mediated cytosolic oxidative signaling to promote gastric cancer progression by ERK activation

Oxidative signaling plays a dual role in tumor initiation and progression to malignancy; however, the regulatory mechanisms of oxidative stress in gastric cancer remain to be explored. In this study, we discovered that Prohibitin 2 (PHB2) specifically regulates cytosolic reactive oxygen species production in gastric cancer and facilitates its malignant progression. Previously, we found that PHB2 is upregulated in gastric cancer, correlating with increased tumorigenicity of gastric cancer cells and poor patient prognosis. Here, we discovered that PHB2 expression correlates with the activation of the ERK/MAPK cascade, positively regulating the top gene NADPH oxidase 1 (NOX1) within this pathway. Further mechanistic investigation reveals that PHB2 enhances NOX1 transcription by interacting with the transcription factor C/EBP-beta and promoting its translocation into the nucleus, resulting in elevated intracellular oxidative signaling driven by NOX1, which subsequently activates ERK. Therefore, we propose that targeting PHB2-C/EBP-beta-NOX1-mediated cytosolic oxidative stress could offer a promising therapeutic avenue for combating gastric cancer malignant progression.

Whole-brain mapping in adult zebrafish and identification of a novel tank test functional connectome

Identifying general principles of brain function requires the study of structure-function relationships in a variety of species. Zebrafish have recently gained prominence as a model organism in neuroscience, yielding important insights into vertebrate brain function. Although methods have been developed for mapping neural activity in larval animals, we lack similar techniques for adult zebrafish that have the advantage of a fully developed neuroanatomy and larger behavioral repertoire. Here, we describe a pipeline built around open-source tools for whole-brain activity mapping in freely swimming adult zebrafish. Our pipeline combines recent advances in histology, microscopy, and machine learning to capture cfos activity across the entirety of the adult brain. Images captured using light-sheet microscopy are registered to the recently created adult zebrafish brain atlas (AZBA) for automated segmentation using advanced normalization tools (ANTs). We used our pipeline to measure brain activity after zebrafish were subject to the novel tank test. We found that cfos levels peaked 15 minutes following behavior and that several regions containing serotoninergic, dopaminergic, noradrenergic, and cholinergic neurons were active during exploration. Finally, we generated a novel tank test functional connectome. Functional network analysis revealed that several regions of the medial ventral telencephalon form a cohesive sub-network during exploration. We also found that the anterior portion of the parvocellular preoptic nucleus (PPa) serves as a key connection between the ventral telencephalon and many other parts of the brain. Taken together, our work enables whole-brain activity mapping in adult zebrafish for the first time while providing insight into neural basis for the novel tank test.

Translation efficiency covariation across cell types is a conserved organizing principle of mammalian transcriptomes

Characterization of shared patterns of RNA expression between genes across conditions has led to the discovery of regulatory networks and novel biological functions. However, it is unclear if such coordination extends to translation, a critical step in gene expression. Here, we uniformly analyzed 3,819 ribosome profiling datasets from 117 human and 94 mouse tissues and cell lines. We introduce the concept of Translation Efficiency Covariation (TEC), identifying coordinated translation patterns across cell types. We nominate potential mechanisms driving shared patterns of translation regulation. TEC is conserved across human and mouse cells and helps uncover gene functions. Moreover, our observations indicate that proteins that physically interact are highly enriched for positive covariation at both translational and transcriptional levels. Our findings establish translational covariation as a conserved organizing principle of mammalian transcriptomes.

Investigating the Regulation of Ribosomal Protein S6 Kinase 1 by CoAlation

Ribosomal protein S6 kinases belong to a family of highly conserved enzymes in eukaryotes that regulate cell growth, proliferation, survival, and the stress response. It is well established that the activation and downstream signalling of p70S6Ks involve multiple phosphorylation events by key regulators of cell growth, survival, and energy metabolism. Here, we report for the first time the covalent modification of p70S6K1 by coenzyme A (CoA) in response to oxidative stress, which regulates its kinase activity. The site of CoA binding (CoAlation) was mapped by mass spectrometry to cysteine 217 (Cys217), located in the kinase activation loop and only one amino acid away from the tripeptide DFG motif, which facilitates ATP-binding. The CoAlation of recombinant p70S6K1 was demonstrated in vitro and was shown to inhibit its kinase activity. Our molecular docking and dynamics analysis revealed the most likely mode for CoA binding to p70S6K1. This mechanism involves the non-covalent binding of the CoA ADP moiety to the p70S6K1 nucleotide-binding pocket, positioning the CoA thiol group in close proximity to form a covalent bond with the surface-exposed Cys217 residue. These findings support a "dual anchor" mechanism for protein kinase inhibition by CoAlation in cellular response to oxidative stress. Furthermore, the inhibition of S6K1 by CoAlation may open new avenues for developing novel inhibitors.

Boolean Modeling of Biological Network Applied to Protein-Protein Interaction Network of Autism Patients

Cellular molecules interact with one another in a structured manner, defining a regulatory network topology that describes cellular mechanisms. Genetic mutations alter these networks' pathways, generating complex disorders such as autism spectrum disorder (ASD). Boolean models have assisted in understanding biological system dynamics since Kauffman's 1969 discovery, and various analytical tools for regulatory networks have been developed. This study examined the protein-protein interaction network created in our previous publication of four ASD patients using the SPIDDOR R package, a Boolean model-based method. The aim is to examine how patients' genetic variations in INTS6L, USP9X, RSK4, FGF5, FLNA, SUMF1, and IDS affect mTOR and Wnt cell signaling convergence. The Boolean network analysis revealed abnormal activation levels of essential proteins such as β-catenin, MTORC1, RPS6, eIF4E, Cadherin, and SMAD. These proteins affect gene expression, translation, cell adhesion, shape, and migration. Patients 1 and 2 showed consistent patterns of increased β-catenin activity and decreased MTORC1, RPS6, and eIF4E activity. However, patient 2 had an independent decrease in Cadherin and SMAD activity due to the FLNA mutation. Patients 3 and 4 have an abnormal activation of the mTOR pathway, which includes the MTORC1, RPS6, and eIF4E genes. The shared mTOR pathway behavior in these patients is explained by a shared mutation in two closely related proteins (SUMF1 and IDS). Diverse activities in β-catenin, MTORC1, RPS6, eIF4E, Cadherin, and SMAD contributed to the reported phenotype in these individuals. Furthermore, it unveiled the potential therapeutic options that could be suggested to these individuals.

Kidney-tonifying blood-activating decoction delays ventricular remodeling in rats with chronic heart failure by regulating gut microbiota and metabolites and p38 mitogen-activated protein kinase/p65 nuclear factor kappa-B/aquaporin-4 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Myocardial infarction has likely contributed to the increased prevalence of heart failure(HF).As a result of ventricular remodeling and reduced cardiac function, colonic blood flow decreases, causing mucosal ischemia and hypoxia of the villous structure of the intestinal wall.This damage in gut barrier function increases bowel wall permeability, leading to fluid metabolism disorder,gut microbial dysbiosis, increased gut bacteria translocation into the circulatory system and increased circulating endotoxins, thus promoting a typical inflammatory state.Traditional Chinese Medicine plays a key role in the prevention and treatment of HF.Kidney-tonifying Blood-activating(KTBA) decoction has been proved for clinical treatment of chronic HF.However,the mechanism of KTBA decoction on chronic HF is still unclear.

AIMS OF THE STUDY

The effect of KTBA decoction on gut microbiota and metabolites and p38MAPK/p65NF-κB/AQP4 signaling in rat colon was studied to investigate the mechanism that KTBA decoction delays ventricular remodeling and regulates water metabolism disorder in rats with HF after myocardial infarction based on the theory of "Kidney Storing Essence and Conducting Water".

MATERIAL AND METHODS

In vivo,a rat model of HF after myocardial infarction was prepared by ligating the left anterior descending coronary artery combined with exhaustive swimming and starvation.The successful modeling rats were randomly divided into five groups:model group, tolvaptan group(gavaged 1.35mg/(kg•D) tolvaptan),KTBA decoction group(gavaged 15.75g/(kg•D) of KTBA decoction),KTBA decoction combined with SB203580(p38MAPK inhibitor) group(gavaged 15.75g/(kg•D) of KTBA decoction and intraperitoneally injected 1.5mg/(kg•D) of SB203580),and KTBA decoction combined with PDTC(p65NF-kB inhibitor) group(gavaged 15.75g/(kg•D) of KTBA decoction and intraperitoneally injected 120mg/(kg•D) of PDTC).The sham-operation group and model group were gavaged equal volume of normal saline.After 4 weeks of intervention with KTBA decoction,the effect of KTBA decoction on the cardiac structure and function of chronic HF model rats was observed by ultrasonic cardiogram.General state and cardiac index in rats were evaluated.Enzyme linked immunosorbent assay(ELISA) was used to measure N-terminal pro-brain natriuretic peptide (NT-proBNP) concentration in rat serum.Hematoxylin and eosin(H&E) staining,and transmission electron microscope(TEM) were used to observe the morphology and ultrastructure of myocardial and colonic tissue,and myocardial fibrosis was measured by Masson's staining.Cardiac E-cadherin level was detected by Western blot.The mRNA expression and protein expression levels of p38MAPK,I-κBα, p65NF-κB,AQP4,Occludin and ZO-1 in colonic tissue were detected by reverse transcription-quantitative real-time polymerase chain reaction(RT-qPCR) and immunohistochemistry. Protein expression of p38MAPK, p-p38MAPK,I-κBα,p-I-κBα,p65NF-κB, p-p65NF-κB,AQP4,Occludin and ZO-1 in rat colon was detected using Western blot.Colonic microbiota and serum metabolites were respectively analyzed by amplicon sequencing and liquid chromatography-mass spectrometry.In vitro, CCD-841CoN cell was placed in the ischemic solution under hypoxic conditions (94%N2,5%CO2,and 1%O2) in a 37 °C incubator to establish an ischemia and hypoxia model.The CCD-841CoN cells were divided into 7 groups, namely blank group and model group with normal rat serum plus control siRNA, tolvaptan group with rat serum containing tolvaptan plus control siRNA, KTBA group with rat serum containing KTBA plus control siRNA, KTBA plus p38MAPK siRNA group, KTBA plus p65NF-κB siRNA group,and KTBA plus AQP4siRNA group.After 24h and 48h of intervention with KTBA decoction,RT-qPCR,immunofluorescence and Western blot was used to detect the mRNA expression and protein expression levels of p38MAPK,I-κBα,p65NF-κB,AQP4, Occludin and ZO-1 in CCD-841CoN cells.

RESULTS

Compared with the model, KTBA decoction improved the general state, decraesed the serum NT-proBNP level,HW/BW ratio, LVIDd and LVIDs, increased E-cadherin level,EF and FS,reduced number of collagen fibers deposited in the myocardial interstitium,and recovered irregular arrangement of myofibril and swollen or vacuolated mitochondria with broken crista in myocardium.Moreover, KTBA decoction inhibited the expression of p38MAPK,I-κBα,and p65NF-κB and upregulated AQP4, Occludin and ZO-1 in colon tissues and CCD-841CoN cells.Additionally,p38siRNA or SB203580, p65siRNA or PDTC, and AQP4siRNA partially weakened the protective effects of KTBA in vitro and vivo.Notably,The LEfSe analysis results showed that there were six gut biomaker bacteria in model group, including Allobaculum, Bacillales,Turicibacter, Turicibacterales,Turicibacteraceae,and Bacilli. Besides, three gut biomaker bacteria containing Deltaproteobacteria, Desulfovibrionaceae,and Desulfovibrionales were enriched by KTBA treatment in chronic HF model.There were five differential metabolites, including L-Leucine,Pelargonic acid, Capsidiol,beta-Carotene,and L- Erythrulose, which can be regulated back in the same changed metabolic routes by the intervention of KTBA.L-Leucine had the positive correlation with Bacillales, Turicibacterales,Turicibacteraceae,and Turicibacter.L-Leucine significantly impacts Protein digestion and absorption, Mineral absorption,and Central carbon metabolism in cancer regulated by KTBA, which is involved in the expression of MAPK and tight junction in intestinal epithelial cells.

CONCLUSIONS

KTBA decoction manipulates the expression of several key proteins in the p38MAPK/p65NF-κB/AQP4 signaling pathway, modulates gut microbiota and metabolites toward a more favorable profile, improves gut barrier function, delays cardiomyocyte hypertrophy and fibrosis,and improves cardiac function.

Role and mechanisms of autophagy, ferroptosis, and pyroptosis in sepsis-induced acute lung injury

Sepsis-induced acute lung injury (ALI) is a major cause of death among patients with sepsis in intensive care units. By analyzing a model of sepsis-induced ALI using lipopolysaccharide (LPS) and cecal ligation and puncture (CLP), treatment methods and strategies to protect against ALI were discussed, which could provide an experimental basis for the clinical treatment of sepsis-induced ALI. Recent studies have found that an imbalance in autophagy, ferroptosis, and pyroptosis is a key mechanism that triggers sepsis-induced ALI, and regulating these death mechanisms can improve lung injuries caused by LPS or CLP. This article summarized and reviewed the mechanisms and regulatory networks of autophagy, ferroptosis, and pyroptosis and their important roles in the process of LPS/CLP-induced ALI in sepsis, discusses the possible targeted drugs of the above mechanisms and their effects, describes their dilemma and prospects, and provides new perspectives for the future treatment of sepsis-induced ALI.

Azilsartan as a preventive agent against cyclophosphamide-induced testicular injury in male rats

Cyclophosphamide (CP) is a popular cancer treatment; however, despite its efficacy, it is known to cause harm to the testicles. To mitigate the reproductive damage caused by CP in male rats, we examined the protective effect of azilsartan (AZ) on CP-induced testicular damage. Thirty Sprague-Dawley male rats were equally divided into three groups: normal control group: received 0.5% CMC suspension for 13 days; induction group: received a single dose of 200 mg/kg of CP on day 6 by intraperitoneal (IP) injection, azilsartan group: received azilsartan (4 mg/kg) orally for 5 days followed by a single dose of 200 mg/kg of (CP) on day 6 by IP injection, then azilsartan administered again for 7 days. Animals were sacrificed on day 14, and sperm characteristics, testosterone levels, and testicular histopathology were evaluated. Induction with CP caused a significant reduction in median value compared to normal control in sperm count (12.0 vs. 22.0 × 106/mm3), sperm motility (30 vs. 90%), abnormal sperm (30.32 vs. 14.43%), dead sperm count (32.43 vs. 10.49 × 106/mm3), DNA fragmentation (21.57 vs. 5.49%); meanwhile, azilsartan prevent these effects on median sperm count (17.0 × 106/mm3), sperm motility (70.0%), abnormal sperm (23.19%), dead sperm count (26.17 × 106/mm3), DNA fragmentation (13.81%), and improved plasmatic testosterone levels compared to the CP group and prevented histopathological alterations of the testes. Azilsartan's mitigation of CP's effects suggests it can prevent male rats' reproductive damage caused by CP. One possible explanation for AZ's protective effects is that it inhibits lipid peroxidation and has antioxidant properties.

Astaxanthin reduces TBPH-induced neurobehavioral deficits in mice by the ROS-ERK1/2-FOS pathway

The persistence of the novel brominated flame retardant, bis(2-ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH), in the environment and its potential for bioaccumulation in living organisms, including humans, further exacerbate its health risks. Therefore, ongoing research is crucial for fully understanding the extent of TBPH's neurotoxicity and for developing effective mitigation strategies. This study aims to investigate the potential neurotoxicity of TBPH on mouse neurobehavior and to evaluate the protective effects of the natural antioxidant astaxanthin (AST) against TBPH-induced neurotoxicity. The results indicate that exposure to TBPH can lead to a decline in learning and memory abilities and abnormal behaviors in mice, which may be associated with oxidative stress responses and apoptosis in the hippocampus. TBPH may disrupt the normal function of hippocampal neurons by activating the extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway. Mice exposed to TBPH treated with AST showed improved learning and memory abilities in the Morris water maze (MWM) and Step-down test (SDT). AST, through its antioxidant action, was able to significantly reduce the increase in reactive oxygen species (ROS) levels induced by TBPH, the increased expression of apoptosis markers, and the activation of the ERK1/2-FOS signaling pathway, alleviating TBPH-induced apoptosis in hippocampal neurons and improving neurobehavioral outcomes. These findings suggest that AST may alleviate the neurotoxicity of TBPH by modulating molecular events related to apoptosis and the ERK1/2-FOS signaling pathway. Thus, this study provides evidence for AST as a potential interventional strategy for the prevention or treatment of cognitive decline associated with environmental neurotoxicant exposure.

A neutrophil elastase-generated mature form of IL-33 is a potent regulator of endothelial cell activation and proliferative retinopathy

Human interleukin-33 (IL-33) is a 270 amino acid protein that belongs to the IL-1 cytokine family and plays an important role in various inflammatory disorders. Neutrophil proteases (Cathepsin G and Elastase) and mast cell proteases (tryptase and chymase) regulate the activity of IL-33 by processing full-length IL-33 into its mature form. There is little evidence on the role of these mature forms of IL-33 in retinal endothelial cell signaling and pathological retinal angiogenesis. Here, we cloned, expressed, and purified the various mature forms of human IL-33 and then evaluated the effects of IL-3395-270, IL-3399-270, IL-33109-270, and IL-33112-270 on angiogenesis in human retinal microvascular endothelial cells (HRMVECs). We observed that IL-3395-270, IL-3399-270, IL-33109-270, and IL-33112-270 significantly induced HRMVEC migration, tube formation and sprouting angiogenesis. However, only IL-3399-270 could induce HRMVEC proliferation. We used a murine model of oxygen-induced retinopathy (OIR) to assess the role of these mature forms of IL-33 in pathological retinal neovascularization. Our 3'-mRNA sequencing and signaling studies indicated that IL-3399-270 and IL-33109-270 were more potent at inducing endothelial cell activation and angiogenesis than the other mature forms. We found that genetic deletion of IL-33 significantly reduced OIR-induced retinal neovascularization in the mouse retina and that intraperitoneal administration of mature forms of IL-33, mainly IL-3399-270 and IL-33109-270, significantly restored ischemia-induced angiogenic sprouting and tuft formation in the hypoxic retinas of IL-33-/- mice. Thus, our study results suggest that blockade or inhibition of IL-33 cleavage by neutrophil proteases could help mitigate pathological angiogenesis in proliferative retinopathies.

Methylsulfinyl Hexyl Isothiocyanate (6-MSITC) from Wasabi Is a Promising Candidate for the Treatment of Cancer, Alzheimer's Disease, and Obesity

Methylsulfinyl hexyl isothiocyanate (6-MSITC) isolated from Eutrema japonicum is a promising candidate for the treatment of breast cancer, colorectal and stomach cancer, metabolic syndrome, heart diseases, diabetes, and obesity due to its anti-inflammatory and antioxidant properties. Also, its neuroprotective properties, improving cognitive function and protecting dopaminergic neurons, make it an excellent candidate for treating neurodegenerative diseases like dementia, Alzheimer's, and Parkinson's disease. 6-MSITC acts on many signaling pathways, such as PPAR, AMPK, PI3K/AKT/mTOR, Nrf2/Keap1-ARE, ERK1/2-ELK1/CHOP/DR5, and MAPK. However, despite the very promising results of in vitro and in vivo animal studies and a few human studies, the molecule has not yet been thoroughly tested in the human population. Nonetheless, wasabi should be classified as a "superfood" for the primary and secondary prevention of human diseases. This article reviews the current state-of-the-art research on 6-MSITC and its potential clinical uses, discussing in detail the signaling pathways activated by the molecule and their interactions.

Design and Synthesis of Marine Polybrominated Diphenyl Ether Derivatives as Potential Anti-Inflammatory Agents

Natural polybrominated diphenyl ethers are generally isolated from sponges and possess a broad range of biological activities. Through screening of our marine natural product library, we discovered that polybrominated diphenyl ethers 5 and 6 exhibit considerable anti-inflammatory activity. In order to expand our repertoire of derivatives for further biological activity studies, we designed and synthesized a series of 5-related polybrominated diphenyl ethers. Importantly, compound 5a showed comparable anti-inflammatory activity while much lower cytotoxicity on lipopolysaccharide (LPS)-induced RAW264.7 cells. Additionally, western blotting analysis showed that 5a reduced the expression of phosphorylated extracellular signal-regulated kinase (p-ERK). Besides, molecular docking experiments were conducted to predict and elucidate the potential mechanisms underlying the varying anti-inflammatory activities exhibited by compounds 5a, 5, and 6.

Molecular mechanisms of spinal cord injury repair across vertebrates: A comparative review

In humans and other adult mammals, axon regeneration is difficult in axotomized neurons. Therefore, spinal cord injury (SCI) is a devastating event that can lead to permanent loss of locomotor and sensory functions. Moreover, the molecular mechanisms of axon regeneration in vertebrates are not very well understood, and currently, no effective treatment is available for SCI. In striking contrast to adult mammals, many nonmammalian vertebrates such as reptiles, amphibians, bony fishes and lampreys can spontaneously resume locomotion even after complete SCI. In recent years, rapid progress in the development of next-generation sequencing technologies has offered valuable information on SCI. In this review, we aimed to provide a comparison of axon regeneration process across classical model organisms, focusing on crucial genes and signalling pathways that play significant roles in the regeneration of individually identifiable descending neurons after SCI. Considering the special evolutionary location and powerful regenerative ability of lamprey and zebrafish, they will be the key model organisms for ongoing studies on spinal cord regeneration. Detailed study of SCI in these model organisms will help in the elucidation of molecular mechanisms of neuron regeneration across species.

Onychocolone A produced by the fungus Onychocola sp. targets cancer stem cells and stops pancreatic cancer progression by inhibiting MEK2-dependent cell signaling

Pancreatic cancer (PC) shows a high fatality rate that can only be faced with a combination of surgery and chemotherapy or palliative treatment in the case of advanced patients. Besides, PC tumors are enriched with subpopulations of cancer stem cells (CSCs) that are resistant to the existing chemotherapeutic agents, which raises an important need for the identification of new drugs. To fill this gap, we have tested the anti-tumoral activity of microbial extracts, which chemical diversity offers a broad spectrum of potential new bioactive compounds. Extracts derived from the fungus Onychocola sp. CF-107644 were assayed via high throughput screening followed by bioassay-guided fractionation and resulted in the identification and isolation of six benzophenone derivatives with antitumoral activity: onychocolones A-F (#1-6). The structures of the compounds were established by spectroscopic methods, including ESI-TOF MS, 1D and 2D NMR analyses and X-ray diffraction. Compounds #1-4 significantly inhibited the growth of the pancreas tumoral cell lines, with low-micromolar Median Effective Doses (ED50s). Compound #1 (onychocolone A) was prioritized for further profiling due to its pro-apoptotic effect, which was further validated on 3D spheroids and pancreatic CSCs. Protein expression assays showed that the effect was mechanistically linked to the inhibition of MEK onco-signaling pathway. The efficacy of onychocolone A was also demonstrated in vivo by the reduction of tumor growth in a pancreatic xenograft mouse model generated by CSCs. Altogether, the data support that onychocolone A is a promising new small molecule for hit-to-lead development of a new treatment for PC.

Irisin as an agent for protecting against osteoporosis: A review of the current mechanisms and pathways

BACKGROUND

Osteoporosis is recognized as a skeletal disorder characterized by diminished bone tissue quality and density. Regular physical exercise is widely acknowledged to preserve and enhance bone health, but the detailed molecular mechanisms involved remain unclear. Irisin, a factor derived from muscle during exercise, influences bone and muscle. Since its discovery in 2012, irisin has been found to promote bone growth and reduce bone resorption, establishing a tangible link between muscle exertion and bone health. Consequently, the mechanism by which irisin prevents osteoporosis have attracted significant scientific interest.

AIM OF THE REVIEW

This study aims to elucidate the multifaceted relationship between exercise, irisin, and bone health. Focusing on irisin, a muscle-derived factor released during exercise, we seek to understand its role in promoting bone growth and inhibiting resorption. Through a review of current research article on irisin in osteoporosis, Our review provides a deep dive into existing research on influence of irisin in osteoporosis, exploring its interaction with pivotal signaling pathways and its impact on various cell death mechanisms and inflammation. We aim to uncover the molecular underpinnings of how irisin, secreted during exercise, can serve as a therapeutic strategy for osteoporosis.

KEY SCIENTIFIC CONCEPTS OF THE REVIEW

Irisin, secreted during exercise, plays a vital role in bridging muscle function to bone health. It not only promotes bone growth but also inhibits bone resorption. Specifically, Irisin fosters osteoblast proliferation, differentiation, and mineralization predominantly through the ERK, p38, and AMPK signaling pathways. Concurrently, it regulates osteoclast differentiation and maturation via the JNK, Wnt/β-catenin and RANKL/RANK/OPG signaling pathways. This review further delves into the profound significance of irisin in osteoporosis and its involvement in diverse cellular death mechanisms, including apoptosis, autophagy, ferroptosis, and pyroptosis.

Therapeutic potential of targeting protein tyrosine phosphatases in liver diseases

Protein tyrosine phosphorylation is a post-translational modification that regulates protein structure to modulate demic organisms' homeostasis and function. This physiological process is regulated by two enzyme families, protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). As an important regulator of protein function, PTPs are indispensable for maintaining cell intrinsic physiology in different systems, as well as liver physiological and pathological processes. Dysregulation of PTPs has been implicated in multiple liver-related diseases, including chronic liver diseases (CLDs), hepatocellular carcinoma (HCC), and liver injury, and several PTPs are being studied as drug therapeutic targets. Therefore, given the regulatory role of PTPs in diverse liver diseases, a collated review of their function and mechanism is necessary. Moreover, based on the current research status of targeted therapy, we emphasize the inclusion of several PTP members that are clinically significant in the development and progression of liver diseases. As an emerging breakthrough direction in the treatment of liver diseases, this review summarizes the research status of PTP-targeting compounds in liver diseases to illustrate their potential in clinical treatment. Overall, this review aims to support the development of novel PTP-based treatment pathways for liver diseases.

Exploring Evolutionary Adaptations and Genomic Advancements to Improve Heat Tolerance in Chickens

Climate change poses a significant threat to the poultry industry, especially in hot climates that adversely affect chicken growth, development, and productivity through heat stress. This literature review evaluates the evolutionary background of chickens with the specific genetic characteristics that can help chickens to cope with hot conditions. Both natural selection and human interventions have influenced the genetic characteristics of the breeds used in the current poultry production system. The domestication of chickens from the Red junglefowl (Gallus gallus) has resulted in the development of various breeds with distinct genetic differences. Over the past few years, deliberate breeding for desirable traits (such as meat production and egg quality) in chickens has resulted in the emergence of various economically valuable breeds. However, this selective breeding has also caused a decrease in the genetic diversity of chickens, making them more susceptible to environmental stressors like heat stress. Consequently, the chicken breeds currently in use may possess a limited ability to adapt to challenging conditions, such as extreme heat. This review focuses on evaluating potential genes and pathways responsible for heat tolerance, including heat shock response, antioxidant defense systems, immune function, and cellular homeostasis. This article will also discuss the physiological and behavioral responses of chicken varieties that exhibit genetic resistance to heat, such as the naked neck and dwarf traits in different indigenous chickens. This article intends to review the current genomic findings related to heat tolerance in chickens that used methods such as the genome-wide association study (GWAS) and quantitative trait loci (QTL) mapping, offering valuable insights for the sustainability of poultry in the face of global warming.

Cereblon deficiency ameliorates carbon tetrachloride-induced acute hepatotoxicity in HepG2 cells by suppressing MAPK-mediated apoptosis

The liver is vulnerable to various hepatotoxins, including carbon tetrachloride (CCl4), which induces oxidative stress and apoptosis by producing reactive oxygen species (ROS) and activating the mitogen-activated protein kinase (MAPK) pathway. Cereblon (CRBN), a multifunctional protein implicated in various cellular processes, functions in the pathogenesis of various diseases; however, its function in liver injury remains unknown. We established a CRBN-knockout (KO) HepG2 cell line and examined its effect on CCl4-induced hepatocellular damage. CRBN-KO cells exhibited reduced sensitivity to CCl4-induced cytotoxicity, as evidenced by decreased levels of apoptosis markers, such as cleaved caspase-3, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities. CRBN deficiency enhanced antioxidant defense, with increased superoxide dismutase activity and glutathione ratios (GSH/GSSG), as well as reduced pro-inflammatory cytokine expression. Mechanistically, the protective effects of CRBN deficiency appeared to involve the attenuation of the MAPK-mediated pathways, particularly through decreased phosphorylation of JNK and ERK. Overall, these results suggest the crucial role of CRBN in mediating the hepatocellular response to oxidative stress and inflammation triggered by CCl4 exposure, offering potential clinical implications for liver injury in a wide range of liver diseases.

Chemotherapeutic Potential of Chlorambucil-Platinum(IV) Prodrugs against Cisplatin-Resistant Colorectal Cancer Cells

Chlorambucil-platinum(IV) prodrugs exhibit multi-mechanistic chemotherapeutic activity with promising anticancer potential. The platinum(II) precursors of the prodrugs have been previously found to induce changes in the microtubule cytoskeleton, specifically actin and tubulin of HT29 colon cells, while chlorambucil alkylates the DNA. These prodrugs demonstrate significant anticancer activity in 2D cell and 3D spheroid viability assays. A notable production of reactive oxygen species has been observed in HT29 cells 72 h post treatment with prodrugs of this type, while the mitochondrial membrane potential was substantially reduced. The cellular uptake of the chlorambucil-platinum(IV) prodrugs, assessed by ICP-MS, confirmed that active transport was the primary uptake mechanism, with platinum localisation identified primarily in the cytoskeletal fraction. Apoptosis and necrosis were observed at 72 h of treatment as demonstrated by Annexin V-FITC/PI assay using flow cytometry. Immunofluorescence measured via confocal microscopy showed significant changes in actin and tubulin intensity and in architecture. Western blot analysis of intrinsic and extrinsic pathway apoptotic markers, microtubule cytoskeleton markers, cell proliferation markers, as well as autophagy markers were studied post 72 h of treatment. The proteomic profile was also studied with a total of 1859 HT29 proteins quantified by mass spectroscopy, with several dysregulated proteins. Network analysis revealed dysregulation in transcription, MAPK markers, microtubule-associated proteins and mitochondrial transport dysfunction. This study confirms that chlorambucil-platinum(IV) prodrugs are candidates with promising anticancer potential that act as multi-mechanistic chemotherapeutics.

Taming the storm: potential anti-inflammatory compounds targeting SARS-CoV-2 MPro

In severe COVID-19 cases, an exacerbated inflammatory response triggers a cytokine storm that can worsen the prognosis. Compounds with both antiviral and anti-inflammatory activities show promise as candidates for COVID-19 therapy, as they potentially act against the SARS-CoV-2 infection regardless of the disease stage. One of the most attractive drug targets among coronaviruses is the main protease (MPro). This enzyme is crucial for cleaving polyproteins into non-structural proteins required for viral replication. The aim of this review was to identify SARS-CoV-2 MPro inhibitors with both antiviral and anti-inflammatory properties. The interactions of the compounds within the SARS-CoV-2 MPro binding site were analyzed through molecular docking when data from crystallographic structures were unavailable. 18 compounds were selected and classified into five different superclasses. Five of them exhibit high potency against MPro: GC-376, baicalein, naringenin, heparin, and carmofur, with IC50 values below 0.2 μM. The MPro inhibitors selected have the potential to alleviate lung edema and decrease cytokine release. These molecules mainly target three critical inflammatory pathways: NF-κB, JAK/STAT, and MAPK, all previously associated with COVID-19 pathogenesis. The structures of the compounds occupy the S1/S2 substrate binding subsite of the MPro. They interact with residues from the catalytic dyad (His41 and Cys145) and/or with the oxyanion hole (Gly143, Ser144, and Cys145), which are pivotal for substrate recognition. The MPro SARS-CoV-2 inhibitors with potential anti-inflammatory activities present here could be optimized for maximum efficacy and safety and be explored as potential treatment of both mild and severe COVID-19.

Retinol Binding Protein 4 Serves as a Potential Tumor Biomarker and Promotes Malignant Behavior in Gastric Cancer

Background

Gastric cancer (GC) is a highly phenotypically heterogeneous disease and is caused by a combination of factors. Retinol binding protein 4 (RBP4) is a member of a family of lipid transport proteins that are involved in the transport of substances between cells and play a crucial role in a variety of cancers. However, the expression and role of RBP4 in GC remain unknown.

Methods

In this study, we explored the expression, prognostic significance, immune microenvironment, drug responsiveness and function of associated signaling pathways of RBP4 in GC using web-based bioinformatics tools. Immunohistochemistry and real-time quantitative PCR were utilized to analyze the tissue and cell expression levels of RBP4. CCK-8, colony formation, EDU incorporation, wound healing and transwell assays were applied to demonstrate the effect of RBP4 on GC cell function. Flow cytometric detection of apoptosis after RBP4 knockdown. Nude mice xenograft model elucidates the role of RBP4 for GC in vivo. Related proteins of the RAS signaling pathway were analyzed by employing Western blot assays.

Results

RBP4 is highly expressed in GC. RBP4 is closely associated with patient survival and sensitivity to a wide range of antitumor agents. Knockdown of RBP4 promoted apoptosis and inhibited cell proliferation, invasion and migration. RBP4 promotes GC tumorigenesis in vivo. Finally, RBP4 modulates the RAS/RAF/ERK axis.

Conclusion

RBP4 may promote gastric carcinogenesis and development through the RAS/RAF/ERK axis and is expected to be a novel target for GC treatment.

A tethering mechanism underlies Pin1-catalyzed proline cis-trans isomerization at a noncanonical site

The prolyl isomerase Pin1 catalyzes the cis-trans isomerization of proline peptide bonds, a non-covalent post-translational modification that influences cellular and molecular processes, including protein-protein interactions. Pin1 is a two-domain enzyme containing a WW domain that recognizes phosphorylated serine/threonine-proline (pS/pT-P) canonical motifs and an enzymatic PPIase domain that catalyzes proline cis-trans isomerization of pS/pT-P motifs. Here, we show that Pin1 uses a tethering mechanism to bind and catalyze proline cis-trans isomerization of a noncanonical motif in the disordered N-terminal activation function-1 (AF-1) domain of the human nuclear receptor PPARγ. NMR reveals multiple Pin1 binding regions within the PPARγ AF-1, including a canonical motif that when phosphorylated by the kinase ERK2 (pS112-P113) binds the Pin1 WW domain with high affinity. NMR methods reveal that Pin1 also binds and accelerates cis-trans isomerization of a noncanonical motif containing a tryptophan-proline motif (W39-P40) previously shown to be involved in an interdomain interaction with the C-terminal ligand-binding domain (LBD). Cellular transcription studies combined with mutagenesis and Pin1 inhibitor treatment reveal a functional role for Pin1-mediated acceleration of cis-trans isomerization of the W39-P40 motif. Our data inform a refined model of the Pin1 catalytic mechanism where the WW domain binds a canonical pS/T-P motif and tethers Pin1 to the target, which enables the PPIase domain to exert catalytic cis-trans isomerization at a distal noncanonical site.

Prospects of compounds of herbal plants as anticancer agents: a comprehensive review from molecular pathways

Cancer refers to the proliferation and multiplication of aberrant cells inside the human body, characterized by their capacity to proliferate and infiltrate various anatomical regions. Numerous biochemical pathways and signaling molecules have an impact on the cancer auto biogenesis process. The regulation of crucial cellular processes necessary for cell survival and proliferation, which are triggered by phytochemicals, is significantly influenced by signaling pathways. These pathways or components are regulated by phytochemicals. Medicinal plants are a significant reservoir of diverse anticancer medications employed in chemotherapy. The anticancer effects of phytochemicals are mediated by several methods, including induction of apoptosis, cessation of the cell cycle, inhibition of kinases, and prevention of carcinogenic substances. This paper analyzes the phytochemistry of seven prominent plant constituents, namely, alkaloids, tannins, flavonoids, phenols, steroids, terpenoids, and saponins, focusing on the involvement of the MAPK/ERK pathway, TNF signaling, death receptors, p53, p38, and actin dynamics. Hence, this review has examined a range of phytochemicals, encompassing their structural characteristics and potential anticancer mechanisms. It has underscored the significance of plant-derived bioactive compounds in the prevention of cancer, utilizing diverse molecular pathways. In addition, this endeavor also seeks to incentivize scientists to carry out clinical trials on anticancer medications derived from plants.

APG-1252 combined with Cabozantinib inhibits hepatocellular carcinoma by suppressing MEK/ERK and CREB/Bcl-xl pathways

BACKGROUND AND PURPOSE

Liver cancer is the fourth leading cause of cancer-related death worldwide, with hepatocellular carcinoma (HCC) being the most common type of primary liver cancer. APG-1252 is a small molecule inhibitor targeting Bcl-2 and Bcl-xl. However, its anti-tumor effects in HCC, alone or in combination with Cabozantinib, have not been extensively studied.

EXPERIMENTAL

Approach: TCGA database analysis was used to analysis the gene expression levels of Bcl-2 and Bcl-xl in HCC tissues. Western blot was employed to detect the protein expression levels. And the inhibitory effects of APG-1252 and Cabozantinib on the proliferation of HCC cell lines was detected by CCK-8. The effect on the migration and invasion of HCC cells was verified by transwell assay. Huh7 xenograft model in nude mice was used to investigate the combination antitumor effect in vivo.

KEY RESULTS

Our study demonstrated that APG-1252 monotherapy inhibited the proliferation and migration ability of HCC cells, and induced HCC cells apoptosis. The combination of APG-1252 and Cabozantinib showed significant synergistic antitumor effects. Furthermore, the in vivo experiment demonstrated that the combination therapy exerted a synergistic effect in delaying tumor growth, notably downregulating MEK/ERK phosphorylation levels. In terms of mechanism, Cabozantinib treatment caused an increase in the phosphorylation levels of CREB and Bcl-xl proteins, while the combination with APG-1252 mitigated this effect, thereby enhanced the antitumor effect of Cabozantinib.

CONCLUSION AND IMPLICATIONS

Our findings suggest that APG-1252 in combination with Cabozantinib offers a more effective treatment strategy for HCC patients, warranting further clinical investigation.

Cytokine Storm in COVID-19: Insight into Pathological Mechanisms and Therapeutic Benefits of Chinese Herbal Medicines

Cytokine storm (CS) is the main driver of SARS-CoV-2-induced acute respiratory distress syndrome (ARDS) in severe coronavirus disease-19 (COVID-19). The pathological mechanisms of CS are quite complex and involve multiple critical molecular targets that turn self-limited and mild COVID-19 into a severe and life-threatening concern. At present, vaccines are strongly recommended as safe and effective treatments for preventing serious illness or death from COVID-19. However, effective treatment options are still lacking for people who are at the most risk or hospitalized with severe disease. Chinese herbal medicines have been shown to improve the clinical outcomes of mild to severe COVID-19 as an adjunct therapy, particular preventing the development of mild to severe ARDS. This review illustrates in detail the pathogenesis of CS-involved ARDS and its associated key molecular targets, cytokines and signalling pathways. The therapeutic targets were identified particularly in relation to the turning points of the development of COVID-19, from mild symptoms to severe ARDS. Preclinical and clinical studies were reviewed for the effects of Chinese herbal medicines together with conventional therapies in reducing ARDS symptoms and addressing critical therapeutic targets associated with CS. Multiple herbal formulations, herbal extracts and single bioactive phytochemicals with or without conventional therapies demonstrated strong anti-CS effects through multiple mechanisms. However, evidence from larger, well-designed clinical trials is lacking and their detailed mechanisms of action are yet to be well elucidated. More research is warranted to further evaluate the therapeutic value of Chinese herbal medicine for CS in COVID-19-induced ARDS.

Unraveling the cryptic functions of mitogen-activated protein kinases Cpk2 and Mpk2 in Cryptococcus neoformans

Mitogen-activated protein kinase (MAPK) pathways are fundamental to the regulation of biological processes in eukaryotic organisms. The basidiomycete Cryptococcus neoformans, known for causing fungal meningitis worldwide, possesses five MAPKs. Among these, Cpk1, Hog1, and Mpk1 have established roles in sexual reproduction, stress responses, and cell wall integrity. However, the roles of Cpk2 and Mpk2 are less understood. Our study elucidates the functional interplay between the Cpk1/Cpk2 and Mpk1/Mpk2 MAPK pathways in C. neoformans. We discovered that CPK2 overexpression compensates for cpk1Δ mating deficiencies via the Mat2 transcription factor, revealing functional redundancy between Cpk1 and Cpk2. We also found that Mpk2 is phosphorylated in response to cell wall stress, a process regulated by the MAPK kinase (MAP2K) Mkk2 and MAP2K kinases (MAP3Ks) Ssk2 and Ste11. Overexpression of MPK2 partially restores cell wall integrity in mpk1Δ by influencing key cell wall components, such as chitin and the polysaccharide capsule. Contrarily, MPK2 overexpression cannot restore thermotolerance and cell membrane integrity in mpk1Δ. These results suggest that Mpk1 and Mpk2 have redundant and opposing roles in the cellular response to cell wall and membrane stresses. Most notably, the dual deletion of MPK1 and MPK2 restores wild-type mating efficiency in cpk1Δ mutants via upregulation of the mating-regulating transcription factors MAT2 and ZNF2, suggesting that the Mpk1 and Mpk2 cooperate to negatively regulate the pheromone-responsive Cpk1 MAPK pathway. Our research collectively underscores a sophisticated regulatory network of cryptococcal MAPK signaling pathways that intricately govern sexual reproduction and cell wall integrity, thereby controlling fungal development and pathogenicity.IMPORTANCEIn the realm of fungal biology, our study on Cryptococcus neoformans offers pivotal insights into the roles of specific proteins called mitogen-activated protein kinases (MAPKs). Here, we discovered the cryptic functions of Cpk2 and Mpk2, two MAPKs previously overshadowed by their dominant counterparts Cpk1 and Mpk1, respectively. Our findings reveal that these "underdog" proteins are not just backup players; they play crucial roles in vital processes like mating and cell wall maintenance in C. neoformans. Their ability to step in and compensate when their dominant counterparts are absent showcases the adaptability of C. neoformans. This newfound understanding not only enriches our knowledge of fungal MAPK mechanisms but also underscores the intricate balance and interplay of proteins in ensuring the organism's survival and adaptability.

Targeting the multifaceted BRAF in cancer: New directions

Activating mutations in the mitogen-activated protein kinase (MAPK) pathway represent driver alterations governing tumorigenesis, metastasis, and therapy resistance. MAPK activation predominantly occurs through genomic alterations in RAS and BRAF. BRAF is an effector kinase that functions downstream of RAS and propagates this oncogenic activity through MEK and ERK. Across cancers, BRAF alterations include gain-of-function mutations, copy-number alterations, and structural rearrangements. In cancer patients, BRAF-targeting precision therapeutics are effective against Class I BRAF alterations (p.V600 hotspot mutations) in tumors such as melanomas, thyroid cancers, and colorectal cancers. However, numerous non-Class I BRAF inhibitors are also in development and have been explored in some cancers. Here we discuss the diverse forms of BRAF alterations found in human cancers and the strategies to inhibit them in patients harboring cancers of distinct origins.

MiR-125b targeted regulation of MKNK2 inhibits multiple myeloma proliferation and invasion

BACKGROUND

An increasing number of studies demonstrate that abnormal miRNA expression contributes to the advancement of many tumors. Nonetheless, the potential role of miR-125b in multiple myeloma (MM) remains unknown.

OBJECTIVES

To explore the potential effects and mechanism of miR-125b in MM.

METHODS

Real-time quantitative PCR was used to measure the expression levels of miR-125b and MKNK2 in a variety of MM samples. Colony formation and cell counting Kit-8 (CCK-8) assays were used to assess cell proliferation, the transwell assay was used to evaluate the cell invasion capability, and dual luciferase reporter gene assay and Western blot were used to examine the interaction between miR-125b and MKNK2.

RESULTS

The levels of miR-125b were higher in MM tissue samples, alongside increased expression of MKNK2. There was a negative correlation between MKNK2 and miR-125b expression in MM tissues. MKNK2 was identified as a direct target gene of miR-125b in MM cells. Overexpression of miR-125b suppressed MM cell growth, colony formation, and invasion. In addition, MKNK2 was found to mediate the effects of miR-125b on cell proliferation, colony formation, and invasion in MM.

CONCLUSIONS

miR-125b acts as a suppressive factor in multiple myeloma and can affect the malignant behavior of MM by regulating the expression of MKNK2.

Anticancer Effect of PtIIPHENSS, PtII5MESS, PtII56MESS and Their Platinum(IV)-Dihydroxy Derivatives against Triple-Negative Breast Cancer and Cisplatin-Resistant Colorectal Cancer

Development of resistance to cisplatin, oxaliplatin and carboplatin remains a challenge for their use as chemotherapies, particularly in breast and colorectal cancer. Here, we compare the anticancer effect of novel complexes [Pt(1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtIIPHENSS), [Pt(5-methyl-1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtII5MESS) and [Pt(5,6-dimethyl-1,10-phenanthroline)(1S,2S-diaminocyclohexane)](NO3)2 (PtII56MESS) and their platinum(IV)-dihydroxy derivatives with cisplatin. Complexes are greater than 11-fold more potent than cisplatin in both 2D and 3D cell line cultures with increased selectivity for cancer cells over genetically stable cells. ICP-MS studies showed cellular uptake occurred through an active transport mechanism with considerably altered platinum concentrations found in the cytoskeleton across all complexes after 24 h. Significant reactive oxygen species generation was observed, with reduced mitochondrial membrane potential at 72 h of treatment. Late apoptosis/necrosis was shown by Annexin V-FITC/PI flow cytometry assay, accompanied by increased sub-G0/G1 cells compared with untreated cells. An increase in S and G2+M cells was seen with all complexes. Treatment resulted in significant changes in actin and tubulin staining. Intrinsic and extrinsic apoptosis markers, MAPK/ERK and PI3K/AKT activation markers, together with autophagy markers showed significant activation of these pathways by Western blot. The proteomic profile investigated post-72 h of treatment identified 1597 MDA-MB-231 and 1859 HT29 proteins quantified by mass spectroscopy, with several differentially expressed proteins relative to no treatment. GO enrichment analysis revealed a statistically significant enrichment of RNA/DNA-associated proteins in both the cell lines and specific additional processes for individual drugs. This study shows that these novel agents function as multi-mechanistic chemotherapeutics, offering promising anticancer potential, and thereby supporting further research into their application as cancer therapeutics.

Impact of aged and virgin polyethylene microplastics on multi end-points effects of freshwater fish tissues

The buildup of plastic waste in aquatic environments presents serious threats to the environment, wildlife, and ultimately to humans. Specifically, microplastics (MPs) ingestion by aquatic animals leads to adverse physiological and toxicological effects. In addition, discarded MPs undergo aging and degradation processes which affect their morphological properties and chemical composition, enhancing the absorption of environmental pollutants. Under this prism, the present research was conducted to investigate and compare the impact of 'aged' versus pristine low-density polyethylene microplastics (PE-MPs) on various toxicity endpoints as biochemical and molecular parameters in the muscle tissue and liver of the freshwater fish species Perca fluviatilis. In parallel, the morphological, physicochemical, and structural changes occurred in "aged" PE-MPs, (after being exposed to UV radiation for 120 days) were studied, significantly illustrating signs of oxidation and crack propagation at the surface of the studied MPs. Fish were exposed to artificial diet reached with virgin and "aged" PE-MPs, sized 100-180 μm, at concentrations of 1 mg/g of dry food for a period of 15-days. Thereafter, liver and muscle tissues were analyzed in relation to multi oxidative parameters. Compared to the control group, the observed changes in the examined fish included increased activities of antioxidant enzymes, as superoxide dismutase, catalase and glutathione reductase, enhanced concentrations of malondialdehyde, protein carbonylation, HSP70 levels, elevated MAPK phosphorylation, induction of ubiquitin-proteins, as well as heightened levels of Bax/Bcl-2 proteins, caspases and differentiated levels of LC3 II/I, SQSTM1/p62. From the studied biomarkers, apoptosis, ubiquitin and hsp70 levels, showed a more sensitive response against the ingested MPs, followed by autophagy, p38MAPK levels, antioxidant enzymes, MDA and carbonylation levels. The effect of "aged" PE-MPs was more pronounced compared to that of the virgin ones. When evaluating the response of all oxidative stress biomarkers across the studied tissues, the liver demonstrates the highest response for the majority of the biomarkers against both virgin and "aged" PE-MPs. These findings strongly indicate that "aged" MPs activate the antioxidant defence mechanisms and impact the cellular well-being of the examined fish species.

The ribotoxic stress response drives UV-mediated cell death

While ultraviolet (UV) radiation damages DNA, eliciting the DNA damage response (DDR), it also damages RNA, triggering transcriptome-wide ribosomal collisions and eliciting a ribotoxic stress response (RSR). However, the relative contributions, timing, and regulation of these pathways in determining cell fate is unclear. Here we use time-resolved phosphoproteomic, chemical-genetic, single-cell imaging, and biochemical approaches to create a chronological atlas of signaling events activated in cells responding to UV damage. We discover that UV-induced apoptosis is mediated by the RSR kinase ZAK and not through the DDR. We identify two negative-feedback modules that regulate ZAK-mediated apoptosis: (1) GCN2 activation limits ribosomal collisions and attenuates ZAK-mediated RSR and (2) ZAK activity leads to phosphodegron autophosphorylation and its subsequent degradation. These events tune ZAK's activity to collision levels to establish regimes of homeostasis, tolerance, and death, revealing its key role as the cellular sentinel for nucleic acid damage.

Detoxification and neurotransmitter clearance drive the recovery of Arma chinensis from β-cypermethrin-triggered knockdown

Natural enemies of arthropods contribute considerably to agriculture by suppressing pests, particularly when combined with chemical control. Studies show that insect recovery after insecticide application is rare. Here, we discovered the recovery of the predatory bug Arma chinensis from knockdown following the application of β-cypermethrin but not five other insecticides. A. chinensis individuals were more tolerant to β-cypermethrin than lepidopteran and coleopteran larvae, which did not recover from knockdown. We assessed A. chinensis recovery by monitoring their respiration and tracking locomotion through the entire process. We identified and verified the trans-regulation of detoxifying genes, including those encoding cytochrome P450s and α/β-hydrolase, which confer recovery from β-cypermethrin exposure in A. chinensis, by mitogen-activated protein kinase (MAPK) and cAMP response element binding protein (CREB). Furthermore, we discovered a novel mechanism, the neurotransmitter clearance, in vivo during the recovery process, by which the insect initiated the removal of excessive dopamine with a degrading enzyme ebony. Overall, these results provide mechanistic insights into the detoxification and neurotransmitter clearance that jointly drive insect recovery from insecticide exposure.

E2F1 Facilitates the Proliferation and Stemness of Gastric Cancer Cells by Activating CDC25B Transcription and Modulating the MAPK Pathway

Gastric cancer (GC) is a health problem that concerns people around the world. CDC25B is an essential cell cycle regulatory factor that is overexpressed in a variety of tumor cells. CDC25B plays a vital part in the progression and proliferation of malignant tumors. However, it is not yet clear that how CDC25B affects the stemness of GC cells. The study used bioinformatics to detect the expression of E2F1 and CDC25B in GC tissues and their correlation, as well as pathways enriched by CDC25B. We detected the expression of E2F1 and CDC25B in GC cell lines using quantitative reverse transcription polymerase chain reaction and tested the combination relationship between E2F1 and CDC25B using chromatin immunoprecipitation (ChIP) and dual-luciferase assays. We measured cell viability using CCK-8 assay, evaluated sphere-forming efficiency using sphere formation assay, and determined cell proliferation ability using colony formation assay. We also analyzed the expression of stemness markers and MAPK pathway-related proteins using western blot. In GC tissues and cells, CDC25B was upregulated. Silencing CDC25B could affect the MAPK pathway, thereby repressing the proliferation and stemness of GC cells. As predicted by bioinformatics, CDC25B had an upstream transcription factor, E2F1, which also had a high expression level in GC. Dual-luciferase and ChIP assays confirmed the combination relationship between the two. Rescue experiments uncovered that overexpression of CDC25B could reverse the impact induced by E2F1 knockdown on proliferation and stemness of cells. In conclusion, E2F1 could activate CDC25B transcription to regulate the MAPK pathway and enhance the proliferation and stemness of GC cells. We revealed a potential regulatory pathway of stemness of GC cells that was mediated by CDC25B, providing new ideas for improving and innovating GC treatment.

Dietary restriction promote sperm remodeling in aged roosters based on transcriptome analysis

BACKGROUND

The breeder rooster has played a pivotal role in poultry production by providing high-quality semen. Typically, fertility peaks between 30 and 40 weeks of age and then declines rapidly from 45 to 55 weeks of age. Research into improving fertility in aging roosters is essential to extend their productive life. While progress has been made, enhancing fertility in aging roosters remains a significant challenge.

METHODS

To identify the genes related to promoting sperm remodeling in aged Houdan roosters, we combined changes in testis and semen quality with transcriptome sequencing (RNA-seq) to analyze the synchrony of semen quality and testis development. In this study, 350-day-old Houdan breeder roosters were selected for RNA-seq analysis in testis tissues from induced molting roosters (D group) and non-induced molting roosters (47DG group). All analyses of differentially expressed genes (DEGs) and functional enrichment were performed. Finally, we selected six DEGs to verify the accuracy of the sequencing by qPCR.

RESULTS

Compared with the 47DG group, sperm motility (P < 0.05), sperm density (P < 0.01), and testis weight (P < 0.05) were significantly increased in roosters in the D group. Further RNA-seq analysis of the testis between the D group and 47DG group identified 61 DEGs, with 21 up-regulated and 40 down-regulated. Functional enrichment analysis showed that the DEGs were primarily enriched in the cytokine-cytokine receptor interaction, Wnt signaling pathway, MAPK signaling pathway, TGF-β signaling pathway, and focal adhesion pathway. The qRT-PCR results showed that the expression trend of these genes was consistent with the sequencing results. WNT5A, FGFR3, AGTR2, TGFβ2, ROMO1, and SLC26A7 may play a role in testis development and spermatogenesis. This study provides fundamental data to enhance the reproductive value of aging roosters.

Personalizing Therapy Outcomes through Mitogen-Activated Protein Kinase Pathway Inhibition in Non-Small Cell Lung Cancer

Lung cancer (LC) is a highly invasive malignancy and the leading cause of cancer-related deaths, with non-small cell lung cancer (NSCLC) as its most prevalent histological subtype. Despite all breakthroughs achieved in drug development, the prognosis of NSCLC remains poor. The mitogen-activated protein kinase signaling cascade (MAPKC) is a complex network of interacting molecules that can drive oncogenesis, cancer progression, and drug resistance when dysregulated. Over the past decades, MAPKC components have been used to design MAPKC inhibitors (MAPKCIs), which have shown varying efficacy in treating NSCLC. Thus, recent studies support the potential clinical use of MAPKCIs, especially in combination with other therapeutic approaches. This article provides an overview of the MAPKC and its inhibitors in the clinical management of NSCLC. It addresses the gaps in the current literature on different combinations of selective inhibitors while suggesting two particular therapy approaches to be researched in NSCLC: parallel and aggregate targeting of the MAPKC. This work also provides suggestions that could serve as a potential guideline to aid future research in MAPKCIs to optimize clinical outcomes in NSCLC.

The roles of phosphorylation of signaling proteins in the prognosis of acute myeloid leukemia

Signaling pathways of Retinoblastoma (Rb) protein, Akt-kinase, and Erk-kinase (extracellular signal-regulated kinase) have an important role in the pathogenesis of acute myeloid leukemia. Constitutive activation of these proteins by phosphorylation contributes to cell survival by regulation of cell cycle, proliferation and proapoptotic signaling processes. According to previous data phosphorylated forms of these proteins represent a worse outcome for cancer patients. We investigated the presence of phosphorylated Rb (P-Rb), Akt (P-Akt) and Erk (P-Erk) proteins by Western blot technique using phospho-specific antibodies in bone marrow or peripheral blood samples of 69 AML patients, 36 patients with myelodysplastic syndrome (MDS) and 10 healthy volunteers. Expression level of PTEN (Phosphatase and tensin homolog) and PHLPP (PH domain and leucine-rich repeat Protein Phosphatase) phosphatases, the negative regulators of Akt kinase pathway were also examined. We tested the effect of these proteins on survival and on the correlation with known prognostic features in AML. We found 46.3% of AML patients had detectable P-Rb, 34.7% had P-Akt and 28.9% had P-Erk protein. 66.1% of patients expressing PTEN, 38.9% PHLPP, 37.2% both PTEN and PHLPP and 32.2% neither PTEN nor PHLPP phosphatases. Compared to nucleophosmin mutation (NPMc) negative samples P-Erk was significantly less in nucleophosmin mutated patients, P-Rb was significantly less in patients' group with more than 30 G/L peripheral leukocyte count by diagnosis. PHLPP was significantly present in FAB type M5. The expression of P-Rb represented significant better overall survival (OS), while P-Akt represented significantly worse event-free survival (EFS) in unfavorable cytogenetics patients. The presence of both PHLPP and PTEN phosphatases contributes to better OS and EFS, although the differences were not statistically significant. We confirmed significant positive correlation between P-Akt and PHLPP. Assessing the phosphorylation of Rb, Akt and Erk may define a subgroup of AML patients who would benefit especially from new targeted treatment options complemented the standard chemotherapy, and it may contribute to monitoring remission, relapse or progression of AML.

Leishmania donovani mitogen-activated protein kinases as a host-parasite interaction interface

Leishmaniasis, a major globally re-emerging neglected tropical disease, has a restricted repertoire of chemotherapeutic options due to a narrow therapeutic index, drug resistance, or patient non-compliance due to toxicity. The disease is caused by the parasite Leishmania that resides in two different forms in two different environments: as sessile intracellular amastigotes within mammalian macrophages and as motile promastigotes in sandfly gut. As mitogen-activated protein kinases (MAPKs) play important roles in cellular differentiation and survival, we studied the expression of Leishmania donovani MAPKs (LdMAPKs). The homology studies by multiple sequence alignment show that excepting LdMAPK1 and LdMAPK2, all thirteen other LdMAPKs share homology with human ERK and p38 isoforms. Expression of LdMAPK4 and LdMAPK5 is less in avirulent promastigotes and amastigotes. Compared to miltefosine-sensitive L. donovani parasites, miltefosine-resistant parasites have higher LdMAPK1, LdMAPK3-5, LdMAPK7-11, LdMAPK13, and LdMAPK14 expression. IL-4-treatment of macrophages down-regulated LdMAPK11, in virulent amastigotes whereas up-regulated LdMAPK5, but down-regulated LdMAPK6, LdMAPK12-15, expression in avirulent amastigotes. IL-4 up-regulated LdMAPK1 expression in both virulent and avirulent amastigotes. IFN-γ-treatment down-regulated LdMAPK6, LdMAPK13, and LdMAPK15 in avirulent amastigotes but up-regulated in virulent amastigotes. This complex profile of LdMAPKs expression among virulent and avirulent parasites, drug-resistant parasites, and in amastigotes within IL-4 or IFN-γ-treated macrophages suggests that LdMAPKs are differentially controlled at the host-parasite interface regulating parasite survival and differentiation, and in the course of IL-4 or IFN-γ dominated immune response.

Identification of diagnostic markers related to inflammatory response and cellular senescence in endometriosis using machine learning and in vitro experiment

OBJECTIVE

To understand the association between chronic inflammation, cellular senescence, and immunological infiltration in endometriosis.

METHODS

Datasets from GEO comprising 108 endometriosis and 97 healthy human samples and the human endometrial stromal cell. Differentially expressed genes were identified using Limma and WGCNA. Inflammatory response-related subtypes were constructed using consensus clustering analysis. The CIBERSORT algorithm and correlation analyses assessed immune cell infiltration. LASSO, SVM-RFE, and RF identified diagnostic genes. Functional enrichment analysis and multifactor regulatory networks established functional effects. Nomograms, internal and external validations, and in vitro experiments validated the diagnostic genes.

RESULTS

Inflammatory response subtypes were highly correlated with the immune activities of B and NK cells. Sixteen genes were associated with inflammatory response and cellular senescence and six diagnostic genes (NLK, RAD51, TIMELESS, TBX3, MET, and BTG3) were identified. The six diagnostic gene models had an area under the curve of 0.828 and their expression was significantly downregulated in endometriosis samples. Low expression of NLK and BTG3 promoted the proliferation, migration, and invasion of endometriotic cells.

CONCLUSIONS

Inflammatory response subtypes were successfully constructed for endometriosis. Six diagnostic genes related to inflammatory response and cellular senescence were identified and validated. Our study provides novel insights for inflammatory response in endometriosis and markers for endometriosis diagnosis and treatment.

Regulation of macrophage polarization and glucose metabolism by the ERK/MAPK-HK1 signaling pathway in paraquat-induced acute lung injury

Acute lung injury is the leading cause of paraquat (PQ) poisoning-related mortality. The mechanism by which macrophages are involved in PQ-induced acute lung injury remains unclear. In recent years, the role of metabolic reprogramming in macrophage functional transformation has received significant attention. The current study aimed to identify the role of altered macrophage glucose metabolism and molecular mechanisms in PQ poisoning-induced acute lung injury. We established a model of acute lung injury in PQ-intoxicated mice via the intraperitoneal injection of PQ. PQ exposure induces macrophage M1 polarization and promotes the release of inflammatory factors, which causes the development of acute lung injury in mice. In vitro analysis revealed that PQ altered glucose metabolism, which could be reversed by siRNA transfection to silence the expression of HK1, a key enzyme in glucose metabolism. RNA sequencing revealed that the ERK/MAPK pathway was the crucial molecular mechanism of PQ pathogenesis. Further, U0126, an ERK inhibitor, could inhibit PQ-induced HK1 activation and macrophage M1 polarization. These findings provide novel insights into the previously unrecognized mechanism of ERK/MAPK-HK1 activation in PQ poisoning.

Recent advances on signaling pathways and their inhibitors in spinal cord injury

Spinal cord injury (SCI) is a serious and disabling central nervous system injury. Its complex pathological mechanism can lead to sensory and motor dysfunction. It has been reported that signaling pathway plays a key role in the pathological process and neuronal recovery mechanism of SCI. Such as PI3K/Akt, MAPK, NF-κB, and Wnt/β-catenin signaling pathways. According to reports, various stimuli and cytokines activate these signaling pathways related to SCI pathology, thereby participating in the regulation of pathological processes such as inflammation response, cell apoptosis, oxidative stress, and glial scar formation after injury. Activation or inhibition of relevant pathways can delay inflammatory response, reduce neuronal apoptosis, prevent glial scar formation, improve the microenvironment after SCI, and promote neural function recovery. Based on the role of signaling pathways in SCI, they may be potential targets for the treatment of SCI. Therefore, understanding the signaling pathway and its inhibitors may be beneficial to the development of SCI therapeutic targets and new drugs. This paper mainly summarizes the pathophysiological process of SCI, the signaling pathways involved in SCI pathogenesis, and the potential role of specific inhibitors/activators in its treatment. In addition, this review also discusses the deficiencies and defects of signaling pathways in SCI research. It is hoped that this study can provide reference for future research on signaling pathways in the pathogenesis of SCI and provide theoretical basis for SCI biotherapy.

Exploring Neuroprotective Effects of Topical Brimonidine in Experimental Diabetic Retinopathy

BACKGROUND/AIM

Diabetic retinopathy is a leading cause of blindness worldwide, characterized by neurovascular dysfunction. This study aimed to investigate the impact of brimonidine, a selective adrenoceptor agonist, on diabetic retinal neurodegeneration, recognizing the critical role of neurodegeneration in diabetic retinopathy.

MATERIALS AND METHODS

Streptozotocin-induced diabetes was established in adult male Sprague-Dawley rats to mimic diabetic retinopathy. Rats, except non-diabetic control rats, received topical applications of 0.15% brimonidine tartrate (treatment group) or balanced salt solution (diabetic control group) twice daily following diabetes induction. Each group comprised six randomly assigned animals. Retinal samples were analyzed using immunofluorescence staining, apoptosis assay, and western blot.

RESULTS

Topical brimonidine treatment reduced apoptosis of retinal ganglion cells at 8 weeks after induction of diabetes (p<0.05). Glial activation induced by diabetes was reduced by brimonidine treatment. Immunoblot and immunofluorescence assay revealed that the decrease in phospho- protein kinase B (AKT) level resulting from diabetes was also attenuated by brimonidine (p<0.05). Furthermore, brimonidine alleviated the decrease in anti-apoptotic proteins [BCL2 apoptosis regulator (BCL2) and BCL-xl] induced by diabetes (p<0.05). Elevation of phospho-p38 mitogen-activated protein kinase (p38MAPK) and p53 in diabetic rats were reduced by brimonidine (p<0.05). Additionally, brimonidine treatment attenuated the upregulation of the pro-apoptotic molecule BCL-2 associated X in retinas of diabetic rats (p<0.05).

CONCLUSION

These findings suggest that topical brimonidine treatment may protect retinal ganglion cells in experimental diabetes by modulating the AKT pathway and reducing pro-apoptotic p38MAPK levels. This presents a potential neuroprotective approach in diabetes, offering the advantage of localized treatment without the added burden of oral medication.

Rack1-mediated ferroptosis affects hindgut development in rats with anorectal malformations: Spatial transcriptome insights

Anorectal malformation (ARM), a common congenital anomaly of the digestive tract, is a result of insufficient elongation of the urorectal septum. The cytoplasmic protein Receptor of Activated C-Kinase 1 (Rack1) is involved in embryonic neural development; however, its role in embryonic digestive tract development and ARM formation is unexplored. Our study explored the hindgut development and cell death mechanisms in ARM-affected rats using spatial transcriptome analysis. We induced ARM in rats by administering ethylenethiourea via gavage on gestational day (GD) 10. On GDs 14-16, embryos from both normal and ARM groups underwent spatial transcriptome sequencing, which identified key genes and signalling pathways. Rack1 exhibited significant interactions among differentially expressed genes on GDs 15 and 16. Reduced Rack1 expression in the ARM-affected hindgut, verified by Rack1 silencing in intestinal epithelial cells, led to increased P38 phosphorylation and activation of the MAPK signalling pathway. The suppression of this pathway downregulated Nqo1 and Gpx4 expression, resulting in elevated intracellular levels of ferrous ions, reactive oxygen species (ROS) and lipid peroxides. Downregulation of Gpx4 expression in the ARM hindgut, coupled with Rack1 co-localisation and consistent mitochondrial morphology, indicated ferroptosis. In summary, Rack1, acting as a hub gene, modulates ferrous ions, lipid peroxides, and ROS via the P38-MAPK/Nqo1/Gpx4 axis. This modulation induces ferroptosis in intestinal epithelial cells, potentially influencing hindgut development during ARM onset.

MicroRNA-409: Molecular functions and clinical applications in cancer

Late diagnosis is one of the main reasons for high mortality rates in cancer patients. Therefore, investigating the molecular mechanisms involved in tumor progression can improve the cancer diagnosis in the early stages of the tumor progression. MicroRNAs (miRNAs) have important roles in regulation of cell growth, proliferation, metabolism, and migration. Since, deregulation of miR-409 has been reported in a wide range of cancers, in the present review, we investigated the molecular mechanisms of miR-409 during tumor progression and invasion. It has been shown that miR-409 functions as a tumor suppressor in different tumor types. MiR-409 can reduce tumor cell proliferation, growth, and migration by regulation of signaling pathways, cellular metabolism, transcription factors, and cellular adhesion. This review can be an effective step in introducing miR-409 as a non-invasive marker in cancer patients.

Chromium levels in placental tissue and neural tube defects: Association and mechanistic study

Human exposure to chromium (Cr) is common but little is known about its adverse effects on pregnancy outcomes. This study aimed to explore the association between Cr exposure and the risk of neural tube defects (NTDs) and the underlying mechanisms of Cr-induced NTDs. 593 controls and 408 NTD cases with placentas were included in this study. Chromium trichloride (Cr(III)) and potassium dichromate (Cr(VI)) were intragastrically administered to pregnant mice and the number of NTDs was recorded. The odds ratio for total NTDs in the highest exposure group in placenta was 4.18 (95% confidence interval (CI), 1.97-8.84). The incidence of fetal NTDs in mice administered with Cr(III) showed a dose-response relationship. Cr(VI) didn't show teratogenicity of NTDs whereas increased the stillbirth rate. Prenatal exposure to Cr(III) increased levels of oxidative stress and apoptosis in fetal mice. RNA-sequencing results indicated significant enrichment of the MAPK pathway. RT-qPCR and Western blot analysis revealed that Cr(III) induced increased expression of p-JNK, p-P38, and Casp3. Toxicological effects can be partly antagonized by antioxidant supplementation. High chromium exposure was associated with increased human NTD risks. Excessive Cr(III) exposure can induce NTDs in fetal mice by increasing apoptosis through upgrading oxidative stress and then activating JNK/P38 MAPK signaling pathway.