miR-145a-5p/SIK1/cAMP-dependent alteration of synaptic structural plasticity drives cognitive impairment induced by coke oven emissions.

Exposure to fine particulate matter (PM) is associated with the neurodegenerative diseases. Coke oven emissions (COEs) in occupational environment are important sources of PM. However, its neurotoxicity is still unclear. Therefore, evaluating the toxicological effects of COE on the nervous system is necessary. In the present study, we constructed mouse models of COE exposure by tracheal instillation. Mice exposed to COE showed signs of cognitive impairment. This was accompanied by a decrease in miR-145a-5p and an increase in SIK1 expression in the hippocampus, along with synaptic structural damage. Our results demonstrated that COE-induced miR-145a-5p downregulation could increase the expression of SIK1 and phosphorylated SIK1, inhibiting the cAMP/PKA/CREB pathway by activating PDE4D, which was associated with reduced synaptic structural plasticity. Furthermore, restoring of miR-145a-5p expression based on COE exposure in HT22 cells could partially reversed the negative effects of COE exposure through the SIK1/PDE4D/cAMP axis. Collectively, our findings link epigenetic regulation with COE-induced neurotoxicity and imply that miR-145a-5p could be an early diagnostic marker for neurological diseases in patients with COE occupational exposure.

Extracellular ATP and cAMP signaling promote Piezo2-dependent mechanical allodynia after trigeminal nerve compression injury.

Trigeminal neuralgia (TN) is a type of severe paroxysmal neuropathic pain commonly triggered by mild mechanical stimulation in the orofacial area. Piezo2, a mechanically gated ion channel that mediates tactile allodynia in neuropathic pain, can be potentiated by a cyclic adenosine monophosphate (cAMP)-dependent signaling pathway that involves the exchange protein directly activated by cAMP 1 (Epac1). To study whether Piezo2-mediated mechanotransduction contributes to peripheral sensitization in a rat model of TN after trigeminal nerve compression injury, the expression of Piezo2 and activation of cAMP signal-related molecules in the trigeminal ganglion (TG) were detected. Changes in purinergic P2 receptors in the TG were also studied by RNA-seq. The expression of Piezo2, cAMP, and Epac1 in the TG of the TN animals increased after chronic compression of the trigeminal nerve root (CCT) for 21 days, but Piezo2 knockdown by shRNA in the TG attenuated orofacial mechanical allodynia. Purinergic P2 receptors P2X4, P2X7, P2Y1, and P2Y2 were significantly up-regulated after CCT injury. In vitro, Piezo2 expression in TG neurons was significantly increased by exogenous adenosine 5'-triphosphate (ATP) and Ca2+ ionophore ionomycin. ATP pre-treated TG neurons displayed elevated [Ca2+ ]i and faster increase in responding to blockage of Na+ /Ca2+ exchanger by KB-R7943. Furthermore, mechanical stimulation of cultured TG neurons led to sustained elevation in [Ca2+ ]i in ATP pre-treated TG neurons, which is much less in naïve TG neurons, or is significantly reduced by Piezo2 inhibitor GsMTx4. These results indicated a pivotal role of Piezo2 in peripheral mechanical allodynia in the rat CCT model. Extracellular ATP, Ca2+ influx, and the cAMP-to-Epac1 signaling pathway synergistically contribute to the pathogenesis and the persistence of mechanical allodynia.

Adenylate control in cAMP signaling: implications for adaptation in signalosomes.

In cAMP-Protein Kinase A (PKA) signaling, A-kinase anchoring protein scaffolds assemble PKA in close proximity to phosphodiesterases (PDE), kinase-substrates to form signaling islands or 'signalosomes'. In its basal state, inactive PKA holoenzyme (R2:C2) is activated by binding of cAMP to regulatory (R)-subunits leading to dissociation of active catalytic (C)-subunits. PDEs hydrolyze cAMP-bound to the R-subunits to generate 5'-AMP for termination and resetting the cAMP signaling. Mechanistic basis for cAMP signaling has been derived primarily by focusing on the proteins in isolation. Here, we set out to simulate cAMP signaling activation-termination cycles in a signalosome-like environment with PDEs and PKA subunits in close proximity to each other. Using a combination of fluorescence polarization and amide hydrogen exchange mass spectrometry with regulatory (RIα), C-subunit (Cα) and PDE8 catalytic domain, we have tracked movement of cAMP through activation-termination cycles. cAMP signaling operates as a continuum of four phases: (1) Activation and dissociation of PKA into R- and C-subunits by cAMP and facilitated by substrate (2) PDE recruitment to R-subunits (3) Hydrolysis of cAMP to 5'-AMP (4) Reassociation of C-subunit to 5'-AMP-bound-RIα in the presence of excess ATP to reset cAMP signaling to form the inactive PKA holoenzyme. Our results demonstrate that 5'-AMP is not merely a passive hydrolysis end-product of PDE action. A 'ligand-free' state R subunit does not exist in signalosomes as previously assumed. Instead the R-subunit toggles between cAMP- or 5'-AMP bound forms. This highlights, for the first time, the importance of 5'-AMP in promoting adaptation and uncovers adenylate control in cAMP signaling.

Enhancement of Monascus yellow pigments production by activating the cAMP signalling pathway in Monascus purpureus HJ11.

BACKGROUND: Monascus azaphilone pigments (MonAzPs), which were produced by Monascus species, have been used as important food colorant and food supplements for more than one billion people during their daily life. Moreover, MonAzPs recently have received more attention because of their diverse physiological activities. However, the high microbial production of MonAzPs is still not always guaranteed. Herein, the aim of this study was to develop an efficient biotechnological process for MonAzPs production. RESULTS: In this study, exogenous cyclic adenosine monophosphate (cAMP) treatment not only induced MonAzPs production, but also stimulated the expression of a cAMP phosphodiesterase gene, named as mrPDE, in M. purpureus HJ11. Subsequently, MrPDE was identified as a cAMP phosphodiesterase by in vitro enzymatic reaction with purified enzyme. Further, a gene knockout mutant of mrPDE was constructed to verify the activation of cAMP signalling pathway. Deletion of mrPDE in M. purpureus HJ11 improved cAMP concentration by 378% and enhanced PKA kinase activity 1.5-fold, indicating that activation of cAMP signalling pathway was achieved. The ΔmrPDE strain produced MonAzPs at 8563 U/g, with a 2.3-fold increase compared with the WT strain. Moreover, the NAPDH/NADP+ ratio of the ΔmrPDE strain was obviously higher than that of the wild type strain, which led to a higher proportion of yellow MonAzPs. With fed-batch fermentation of the ΔmrPDE strain, the production and yield of MonAzPs achieved 332.1 U/mL and 8739 U/g. CONCLUSIONS: A engineered M. purpureus strain for high MonAzPs production was successfully developed by activating the cAMP signalling pathway. This study not only describes a novel strategy for development of MonAzPs-producing strain, but also provides a roadmap for engineering efforts towards the production of secondary metabolism in other filamentous fungi.

Pregnancy-induced Cushing's syndrome with an adrenocortical adenoma overexpressing LH/hCG receptors: a case report.

BACKGROUND: Pregnancy-induced Cushing's syndrome (CS) with an adrenocortical adenoma overexpressing luteinizing hormone (LH)/human choriogonadotropin (hCG) receptors (LHCGR) has been rarely reported in the literatures. This peculiar condition challenges the canonical diagnosis and management of CS. CASE PRESENTATION: A 27-year-old woman (G2P0A1) presented at 20 weeks gestational age (GA) with overt Cushingoid clinical features. Adrenocorticotropic hormone (ACTH)-independent CS was diagnosed based on undetectable ACTH and unsuppressed cortisol levels by dexamethasone. Magnetic resonance imaging (MRI) scanning without contrast revealed a left adrenal nodule while pituitary MRI scanning was normal. A conservative treatment strategy of controlling Cushingoid comorbidities was conducted. At 36 weeks GA, a caesarean operation was performed and a live female infant was delivered. At 8 weeks after parturition, our patient achieved normalization of blood pressure, blood glucose, serum potassium, and urinary cortisol level spontaneously. During non-pregnancy period, stimulation testing with exogenous hCG significantly evoked a cortisol increase. The woman underwent resection of the adrenal tumor at 6 months after parturition. Immunohistochemistry (IHC) showed the tumor tissue that stained positive for luteinizing hormone (LH)/human choriogonadotropin (hCG) receptor (LHCGR), whereas negative for both melanocortin 2 receptor (MC2R) and G protein-coupled receptor-1 (GPER-1). CONCLUSIONS: Stimulation test with exogenous hCG after parturition is necessary for the diagnosis of pregnancy-induced CS. LHCGR plays an essential role in the pathogenesis of this rare condition.

microRNA-665 silencing improves cardiac function in rats with heart failure through activation of the cAMP signaling pathway.

Heart failure (HF) is a disease with high mortality and morbidity rate. Previous studies have shown that microRNAs (miRNAs) may be implicated in the pathogenesis of HF, potentially being able to improve the cardiac function in an HF rat model. The present study was designed to define the role of miR-665 in the cardiac function of the HF rats. Following the establishm;ent of the rat models of HF, the functional role miR-665 in HF was determined using an ectopic expression and knockdown experiments. The cardiac function was evaluated with the determination of ventricular mass index and hemodynamic parameters. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining was performed, with the apoptosis of cardiac cells detected in the process. The expression of miR-665, glucagon-like peptide 1 receptor (GLP1R), cyclic adenosine monophosphate (cAMP) signaling pathway-related, and apoptosis-related genes was examined. Enzyme-linked immunosorbent assay was conducted to determine the levels of inflammation-related genes. Initially, the upregulation of miR-665, downregulation of GLP1R, and inactivation of cAMP signaling pathway were observed in HF rats. GLP1R was a target of miR-665. Forced expression of miR-665 promoted cell apoptosis and inhibited GLP1R and the cAMP signaling pathway. In addition, miR-665 overexpression has been known to impair cardiac function, promote inflammatory response while elevating malondialdehyde and superoxide dismutase levels, and decreasing mitochondrial respiratory chain enzyme activities. Furthermore, we also observed that the effects of miR-665 inhibition had been reversed when the cAMP signaling pathway was also inhibited. This study demonstrates that miR-665 inhibition can stabilize the cardiac function of HF rats via the cAMP signaling pathway via upregulation of the GLP1R.

Neuroendocrine immune-regulatory of a neuropeptide ChGnRH from the Hongkong oyster, Crassostrea Hongkongensis.

It is increasingly appreciated that neuroendocrine-immune interactions hold the key to understand the complex immune system. In this study, we explored the role of a reproductive regulation-related hormone, GnRH, in the regulation of immunity in Hong Kong oysters. We found that vibrio bacterial strains injection increased the expression of ChGnRH. Moreover, ChGnRH neuropeptide promotes the phagocytic ability and bacterial clearance effect of hemocytes which regarded to be the central immune organ. The content of cAMP after incubation with ChGnRH peptide was increased, which could be blocked by adenylyl cyclase inhibitor SQ 22,536. Furthermore, the stimulated effect of ChGnRH peptide on the phagocytosis and bacterial clearance was also blocked by SQ 22,536, H89 and enzastaurin, strongly demonstrating that cAMP dependent PKA and PKC signaling pathway was involved in ChGnRH mediated immune regulation. In conclusion, this study confirms the presence of neuroendocrine-immune regulatory system in marine invertebrates, which contributes to understand the complexity of oyster immune defense system.

Systems Approach to Identify Common Genes and Pathways Associated with Response to Selective Serotonin Reuptake Inhibitors and Major Depression Risk.

Despite numerous studies on major depressive disorder (MDD) susceptibility, the precise underlying molecular mechanism has not been elucidated which restricts the development of etiology-based disease-modifying drug. Major depressive disorder treatment is still symptomatic and is the leading cause of (~30%) failure of the current antidepressant therapy. Here we comprehended the probable genes and pathways commonly associated with antidepressant response and MDD. A systematic review was conducted, and candidate genes/pathways associated with antidepressant response and MDD were identified using an integrative genetics approach. Initially, single nucleotide polymorphisms (SNPs)/genes found to be significantly associated with antidepressant response were systematically reviewed and retrieved from the candidate studies and genome-wide association studies (GWAS). Also, significant variations concerning MDD susceptibility were extracted from GWAS only. We found 245 (Set A) and 800 (Set B) significantly associated genes with antidepressant response and MDD, respectively. Further, gene set enrichment analysis revealed the top five co-occurring molecular pathways (p ≤ 0.05) among the two sets of genes: Cushing syndrome, Axon guidance, cAMP signaling pathway, Insulin secretion, and Glutamatergic synapse, wherein all show a very close relation to synaptic plasticity. Integrative analyses of candidate gene and genome-wide association studies would enable us to investigate the putative targets for the development of disease etiology-based antidepressant that might be more promising than current ones.

Environmental pH adaption and morphological transitions in Candida albicans.

The human fungal pathogen Candida albicans encounters a wide range of pH stresses during its commensal and pathogenic lifestyles. It has been well studied that environmental pH regulates the yeast-filamentous growth transition in this fungus. White-opaque switching is another type of phenotypic transitions in C. albicans. White and opaque cells are two morphologically and functionally distinct cell types, which differ in many aspects including global gene expression profiles, virulence, mating competency, and susceptibility to antifungals. The switch between white and opaque cell types is heritable and epigenetically regulated. In a recently study, Sun et al. (Eukaryot Cell 14:1127-1134, 2015) reported that pH plays a critical role in the regulation of the white-opaque phenotypic switch and sexual mating in C. albicans via both the conserved Rim101-mediated pH sensing and cAMP signaling pathways. The effect of pH on the two biological processes may represent a balancing act between host environmental adaptation and sexual reproduction in this pathogenic fungus.

The putative Gγ subunit gene MGG1 is required for conidiation, appressorium formation, mating and pathogenicity in Magnaporthe oryzae.

Heterotrimeric G-proteins play key roles in the transduction of extracellular signals to various downstream effectors in eukaryotes. In our previous study, a T-DNA insertional mutant A1-412, in which the promoter of a putative Gγ subunit gene MGG1 was disrupted, was impaired in asexual/sexual sporulation, appressorium formation, and pathogenicity in Magnaporthe oryzae. Here the roles of MGG1 in regulating fungal development and plant infection were further investigated and verified using a gene deletion strategy. Targeted gene deletion mutants of MGG1 exhibited similar phenotypes to those of A1-412. The Δmgg1 mutants were unable to differentiate appressorium on hydrophobic surfaces and nonpathogenic to susceptible hosts. The defects of the Δmgg1 mutants in appressorium formation were partially restored by adding exogenous cAMP or IBMX (a phosphodiesterase inhibitor), although the induced appressoria were still nonfunctional. Expressing Mgg1-GFP fusion protein in an Δmgg1 mutant could complement all phenotypes of the mutant, and bright GFP fluorescence was observed at the periphery of fungal cells, indicating that Mgg1 mainly localizes to plasma membrane. Quantitative RT-PCR analysis revealed that deletion of MGG1 resulted in a significant reduction in mRNA levels of the genes encoding Gα (MagA, MagB, and MagC), Gß (Mgb1), and adenylate cyclase (Mac1). Moreover, intracellular cAMP accumulation was significantly reduced in Δmgg1 mutants compared to that in the wild-type strain. Taken together, our results suggested that Gγ subunit Mgg1 might act upstream of cAMP signaling pathway and play critical roles in regulation of conidiation, appressorium formation, mating, and plant infection in M. oryzae.

The Effect of the cAMP Signaling Pathway on HTR8/SV-Neo Cell Line Proliferation, Invasion, and Migration After Treatment with Forskolin.

Pre-eclampsia (PE) is thought to be related to placental dysfunction, particularly poor extravillous trophoblast (EVT) invasion and migration abilities. However, the pathogenic mechanism is not fully understood. This article describes the impact of the cyclic adenosine monophosphate(cAMP) signaling pathway on EVT behavior, focusing on EVT proliferation, invasion, and migration. Here, we used the HTR8/SV-neo cell line to study human EVT function in vitro. HTR8/SV-neo cells were treated with different concentrations of forskolin (cAMP pathway-specific agonist) to alter intracellular cAMP levels, and dimethyl sulfoxide (DMSO) was used as the control. First, a cAMP assay was performed to measure the cAMP concentration in HTR8/SV-neo cells treated with different forskolin concentrations, and cell proliferation was assessed by constructing cell growth curves and assessing colony formation. Cell invasion and migration were observed by Transwell experiments, and intracellular epithelial-mesenchymal transition (EMT) marker expression was evaluated by quantitative real-time polymerase chain reaction (qPCR) and Western blotting (WB). According to our research, the intracellular cAMP levels in HTR8/SV-neo cells were increased in a dose-dependent manner, and HTR8/SV-neo cell proliferation, invasion and migration were significantly enhanced. The expression of EMT and angiogenesis markers was upregulated. Additionally, with the increase in intracellular cAMP levels, the phosphorylation of intracellular mitogen-activated protein kinase (MAPK) signaling pathway components was significantly increased. These results suggested that the cAMP signaling pathway promoted the phosphorylation of MAPK signaling components, thus enhancing EVT functions, including proliferation, invasion, and migration, and to a certain extent, providing a novel direction for the treatment of PE patients.

Structural and pharmacological characterization of a medium-chain fatty acid receptor GPR84 in common carp (Cyprinus carpio).

The medium-chain fatty acid receptor GPR84, a member of the G protein-coupled receptor family, is mainly expressed in macrophages and microglia, and is involved in the regulation of inflammatory responses and retinal development in mammals and amphibians. However, structure, tissue distribution, and pharmacology of this receptor have rarely been reported in fish. In this study, we cloned the coding sequence (CDS) of common carp GPR84 (ccGPR84), examined its tissue distribution, and explored its cellular signaling function. The results showed that the CDS of ccGPR84 is 1191 bp and encodes a putative protein with 396 amino acids. Phylogenetic and chromosomal synteny analyses revealed that ccGPR84 was evolutionarily conserved with Cyprinids. Real-time quantitative PCR (qPCR) indicated that ccGPR84 was predominantly expressed in the intestine and spleen. Luciferase reporter assay demonstrated that nonanoic acid, capric acid (decanoic acid), undecanoic acid and lauric acid could inhibit cAMP signaling pathway and activate MAPK/ERK signaling pathway, while the potencies of these four fatty acids on the two signaling pathways were different. Lauric acid has the highest inhibitory potency on cAMP signaling pathway, followed by undecanoic acid, nonanoic acid, and capric acid. While for MAPK/ERK signaling pathway, nonanoic acid has the highest activation potency, followed by undecanoic acid, capric acid, and lauric acid. These findings lay the foundation for revealing the roles of different medium-chain fatty acids in the inflammatory response of common carp.

Unlocking the role of EIF5A: A potential diagnostic marker regulating the cell cycle and showing negative correlation with immune infiltration in lung adenocarcinoma.

BACKGROUND: Despite EIF5A upregulation related to tumor progression in LUAD (lung adenocarcinoma), the underlying mechanisms remain elusive. In addition, there are few comprehensive analyses of EIF5A in LUAD. METHODS: We investigated the EIF5A expression level in LUAD patients using data from the TCGA and GEO databases. We employed qRT-PCR and western blot to verify EIF5A expression in cell lines, while immunohistochemistry was utilized for clinical sample analysis. We analyzed EIF5A expression in tumor-infiltrating immune cells using the TISCH database and assessed its association with immune infiltration in LUAD using the "ESTIMATE" R package. Bioinformatics approaches were developed to discover the EIF5A-related genes and explore EIF5A potential mechanisms in LUAD. Proliferation ability was verified through CCK-8, clone formation, and EdU assays, while flow cytometry assessed apoptosis and cell cycle. Western blot was used to detect the expression of pathway-related proteins. RESULTS: EIF5A was significantly upregulated in LUAD. Moreover, we constructed a MAZ-hsa-miR-424-3p-EIF5A transcriptional network. We explored the potential mechanism of EIF5A in LUAD and further investigated the cAMP signaling pathway and the cell cycle. Finally, we proved that EIF5A silencing induced G1/S Cell Cycle arrest, promoted apoptosis, and inhibited proliferation via the cAMP/PKA/CREB signaling pathway. CONCLUSION: EIF5A serves as a prognostic biomarker with a negative correlation to immune infiltrates in LUAD. It regulated the cell cycle in LUAD by inhibiting the cAMP/PKA/CREB signaling pathway.

Mechanism of action of the Banxia-Xiakucao herb pair in sleep deprivation: New comprehensive evidence from network pharmacology, transcriptomics and molecular biology experiments.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herb pairs are the most basic and compressed examples of Chinese herbal combinations and can be used to effectively explain the fundamental concepts of traditional Chinese medicine prescriptions. These pairings have gained significant interest due to their subtle therapeutic benefits, minimal side effects, and efficacy in treating complicated chronic conditions. The Banxia-Xiakucao Chinese herb pair (BXHP) consists of Pinellia ternata (Thunb.) Breit. (Banxia) and Prunella vulgaris L. (Xiakucao). This formula was documented in The Medical Classic of the Yellow Emperor approximately 2000 years ago，and clinical research has demonstrated that BXHP effectively treats insomnia. AIM OF THE STUDY: This study aimed to evaluate the efficacy and therapeutic mechanism of the BXHP through a comprehensive strategy involving network pharmacology, molecular docking, transcriptomics, and molecular biology experimental validation. MATERIALS AND METHODS: The composition of BXHP was characterized using the UPLC-Q-TOF-MS. The active compounds were screened to find drug-likeness compounds by analyzing the ADME data. To predict the molecular mechanism of BXHP in sleep deprivation (SD) by network pharmacology and molecular docking. We established a rat model of SD and the in vivo efficacy of BXHP was verified through the pentobarbital sodium righting reflex test, behavioral assays, enzyme-linked immunosorbent assay, transmission electron microscopy, HE staining, and Nissl staining, and the underlying molecular mechanism of BXHP in SD was revealed through transcriptomic and bioinformatic analyses in conjunction with quantitative real-time PCR, Western blot, and immunofluorescence staining. RESULTS: In the present study, we showed for the first time that BXHP reduced sleep latency, prolongs sleep duration, and improves anxiety; lowered serum CORT, IL6, TNF-α and MDA levels; decreased hypothalamic Glu levels; and elevated hypothalamic GABA and 5-HT levels in SD rats. We found 16 active compounds that acted on 583 targets, 145 of which are related to SD. By modularly dissecting the PPI network, we discovered three critical targets, Akt1, CREB1, and PRKACA, all of which play important roles in the effects of BXHP on SD. Molecular docking resulted in the identification of 16 active compounds that strongly bind to key targets. The results of GO and KEGG enrichment analyses of network pharmacology and transcriptomics focused on both the regulation of circadian rhythm and the cAMP signaling pathway, which strongly demonstrated that BXHP affects SD via the cAMP-PKA-CREB-Circadian rhythm pathway. Molecular biology experiments verified this hypothesis. Following BXHP administration, PKA and CREB phosphorylation levels were elevated in SD rats, the cAMP-PKA-CREB signaling pathway was activated, the expression levels of the biological clock genes CLOCK, p-BMAL1/BMAL1, and PER3 were increased, and the rhythmicity of the biological clock was improved. CONCLUSIONS: The active compounds in BXHP can activate the cAMP-PKA-CREB-Circadian rhythm pathway, improve the rhythmicity of the biological clock, promote sleep and ameliorate anxiety, which suggests that BXHP improves SD through a multicomponent, multitarget, multipathway mechanism. This study is important for the development of herbal medicines and clinical therapies for improving sleep deprivation.

Regulatory pathways and therapeutic potential of PDE4 in liver pathophysiology.

Phosphodiesterase 4 (PDE4), crucial in regulating the cyclic adenosine monophosphate (cAMP) signaling pathway, significantly impacts liver pathophysiology. This article highlights the comprehensive effects of PDE4 on liver health and disease, and its potential as a therapeutic agent. PDE4's role in degrading cAMP disrupts intracellular signaling, increasing pro-inflammatory cytokines like tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6). This contributes to liver inflammation in conditions such as hepatitis and non-alcoholic steatohepatitis (NASH). Additionally, PDE4 is a key factor in liver fibrosis, characterized by excessive extracellular matrix deposition. Inhibiting PDE4 shows promise in reducing liver fibrosis by decreasing the activation of hepatic stellate cells, which is pivotal in fibrogenesis. PDE4 also influences hepatocyte apoptosis a common feature of liver diseases. PDE4 inhibitors protect against hepatocyte apoptosis by raising intracellular cAMP levels, thus activating anti-apoptotic pathways. This suggests potential in targeting PDE4 to prevent hepatocyte loss. Moreover, PDE4 regulates hepatic glucose production and lipid metabolism, essential for liver function. Altering cAMP levels through PDE4 affects enzymes in these metabolic pathways, making PDE4 a target for metabolic disorders like type 2 diabetes and non-alcoholic fatty liver disease (NAFLD). Since PDE4 plays a multifaceted role in liver pathophysiology, influencing PDE4's mechanisms in liver diseases could lead to novel therapeutic strategies. Still, extensive research is required to explore the molecular mechanisms and clinical potential of targeting PDE4 in liver pathologies.

ADCY3: the pivotal gene in classical ketogenic diet for the treatment of epilepsy.

Objective: Epilepsy is a common neurological disorder characterized by recurrent epilepsy episodes. As a non-pharmacological treatment, the ketogenic diet has been widely applied in treating epilepsy. However, the exact therapeutic mechanism of the ketogenic diet for epilepsy remains unclear. This study investigates the molecular mechanisms of the ketogenic diet in regulating fatty acid metabolism and activating the ADCY3-initiated cAMP signaling pathway to enhance neuronal inhibition and thereby treat epilepsy. Methods and results: Meta-analysis reveals that the ketogenic diet is superior to the conventional diet in treating epilepsy. Animal experiments demonstrate that the ketogenic diet is more effective than the conventional diet in treating epilepsy, with the best results achieved using the classic ketogenic diet. Transcriptome sequencing analysis identifies six essential genes, among which ADCY3 shows increased expression in the ketogenic diet. In vivo experiments confirm that the activation of the cAMP-PKA signaling pathway by ADCY3 enhances neuronal inhibition and improves epilepsy control. Conclusion: Clinical observations indicate that the ketogenic diet improves patient epilepsy episodes by regulating the ADCY3-initiated cAMP signaling pathway.

ITGB1 alleviates osteoarthritis by inhibiting cartilage inflammation and apoptosis via activating cAMP pathway.

OBJECTIVE: We aimed to screen novel biomarkers for osteoarthritis (OA) using bioinformatic methods and explore its regulatory mechanism in OA development. METHODS: Differentially expressed genes were screened out from GSE98918 and GSE82107 datasets. Protein-protein interaction network and enrichment analysis were employed to search for hub gene and regulatory pathway. Hematoxylin-eosin, Safranin O-Fast green staining, and immunohistochemistry were performed to assess pathological damage. TNF-α, IL-1ß, and IL-6 concentrations were determined by enzyme-linked immunosorbent assay. Real-time quantitative PCR was applied to verify expression of hub genes in OA model. The expression of key protein and pathway proteins was determined by western blot. Furthermore, Cell Counting Kit-8 and flow cytometry were conducted to explore the role of hub gene in chondrocytes. RESULTS: We identified 6 hub genes of OA, including ITGB1, COL5A1, COL1A1, THBS2, LAMA1, and COL12A1, with high prediction value. ITGB1 was screened as a pivotal regulator of OA and cAMP pathway was selected as the key regulatory pathway. ITGB1 was down-regulated in OA model. ITGB1 overexpression attenuated pathological damage and apoptosis in OA rats with the reduced levels of TNF-α, IL-1ß and IL-6. ITGB1 overexpression activated cAMP pathway in vivo and vitro models. In vitro model, ITGB1 overexpression promoted cell viability, while inhibited apoptosis. ITGB1 overexpression also caused a decrease of TNF-α, IL-1ß, and IL-6 concentrations. cAMP pathway inhibitor reversed the positive effect of ITGB1 on OA cell model. CONCLUSION: ITGB1 is a novel biomarker for OA, which inhibits OA development by activating the cAMP pathway.

Phosducin-like protein PoPlp1 impacts cellulase and amylase expression and development in Penicillium oxalicum via the G protein-cAMP signaling pathway.

In this study, a phosducin-like protein, PoPlp1, was identified and functionally studied in the cellulase-producing strain Penicillium oxalicum 114-2. PoPlp1 was proven to participate in several biological processes, including mycelium development, conidiation, and expression of cellulases and amylases. With deletion of Poplp1, morphology and development varied significantly in ΔPoplp1. Colony growth, glucose utilization, and the hydrolysis capability of starch and cellulose were limited, whereas conidiation was enhanced. Based on detection of the levels of expression of transcription factors involved in asexual development, we conjectured that PoPlp1 is involved in conidiation via the major factor BrlA. We explored the effect of PoPlp1 on cellulase and amylase expression and observed that cellulase and amylase activity and major gene transcription levels were all dramatically reduced in ΔPoplp1. Deletion of PoPlp1 caused a decrease in intracellular cAMP levels, and the cellulase gene expression level of ΔPoplp1 was restored to a certain extent through external addition of cAMP. These findings demonstrate that PoPlp1 may affect cellulase and amylase expression by regulating cAMP concentration. To comprehensively explore the mechanism of PoPlp1 in regulating multiple biological processes, we performed a comparative transcriptomic analysis between strains P. oxalicum 114-2 and ΔPoplp1. The major cellulase and amylase genes were all downregulated, congrent with the results of real-time quantitative polymerase chain reaction analysis. The genes involved in the G protein-cAMP signaling pathway, including several G-protein-coupled receptors, one regulator of G protein signaling, and two cAMP phosphodiesterases, were disrupted by deletion of PoPlp1. These results confirm the positive function of PoPlp1 in the G protein-cAMP signaling pathway. This functional analysis of PoPlp1 will be very beneficial for further study of the regulatory mechanisms of cellulase expression and other biological processes in P. oxalicum 114-2 via the G protein-cAMP signaling pathway.

Function of m5C RNA methyltransferase NOP2 in high-grade serous ovarian cancer.

RNA methyltransferase nucleolar protein p120 (NOP2), commonly referred to as NOP2/Sun RNA methyltransferase family member 1 (NSUN1), is involved in cell proliferation and is highly expressed in various cancers. However, its role in high-grade serous ovarian cancer (HGSOC) remains unclear. Our study investigated the expression of NOP2 in HGSOC tissues and normal fimbria tissues, and found that NOP2 was significantly upregulated in HGSOC tissues. Our experiments showed that NOP2 overexpression promoted cell proliferation in vivo and in vitro and increased the migration and invasion ability of HGSOC cells in vitro. Furthermore, we identified Rap guanine nucleotide exchange factor 4 (RAPGEF4) as a potential downstream target of NOP2 in HGSOC. Finally, our findings suggest that the regulation of NOP2 and RAPGEF4 may depend on m5C methylation levels.

Integrating Network Pharmacology, Molecular Docking and Pharmacological Evaluation for Exploring the Polyrhachis vicina Rogers in Ameliorating Depression.

Purpose: To investigate the mechanisms of antidepressant action of active fraction of Polyrhachis vicina Rogers (AFPR) through network pharmacology, molecular docking and experimental validation. Methods: GC-MS was used to predict chemical compounds, corresponding databases were used to predict chemical compound targets and depression targets, Cytoscape software was used to construct and analyze the protein interaction network map, DAVID database was used to analyze gene ontology (GO) and KEGG signaling pathway, and AGFR software was used to perform molecular docking. Subsequently, the underlying action mechanisms of AFPR on depression predicted by network pharmacology analyses were experimentally validated in a CORT-induced depression model in vitro and in vivo. Results: A total of 52 potential targets of AFPR on antidepressant were obtained. GO is mainly related to chemical synaptic transmission, signal transduction and others. KEGG signaling pathways are mainly related to cAMP signaling pathway and C-type lectin receptor signaling pathway. The experiment results showed that AFPR significantly increased the expression of PRKACA, CREB and BDNF in mouse brain tissue and PC12 cells. Furthermore, after interfered of cAMP in PC12 cells, the decreased expression of PRKACA, CREB and BDNF was reversed by AFPR. Conclusion: AFPR may exert antidepressant effects through multiple components, targets and pathways. Furthermore, it could improve neuroplasticity via the cAMP signaling pathway to improve depression-like symptoms.