MAP kinases and the control of nuclear events

Targeting the RAS upstream and downstream signaling pathway for cancer treatment

Cancer often involves the overactivation of RAS/RAF/MEK/ERK (MAPK) and PI3K-Akt-mTOR pathways due to mutations in genes like RAS, RAF, PTEN, and PIK3CA. Various strategies are employed to address the overactivation of these pathways, among which targeted therapy emerges as a promising approach. Directly targeting specific proteins, leads to encouraging results in cancer treatment. For instance, RTK inhibitors such as imatinib and afatinib selectively target these receptors, hindering ligand binding and reducing signaling initiation. These inhibitors have shown potent efficacy against Non-Small Cell Lung Cancer. Other inhibitors, like lonafarnib targeting Farnesyltransferase and GGTI 2418 targeting geranylgeranyl Transferase, disrupt post-translational modifications of proteins. Additionally, inhibition of proteins like SOS, SH2 domain, and Ras demonstrate promising anti-tumor activity both in vivo and in vitro. Targeting downstream components with RAF inhibitors such as vemurafenib, dabrafenib, and sorafenib, along with MEK inhibitors like trametinib and binimetinib, has shown promising outcomes in treating cancers with BRAF-V600E mutations, including myeloma, colorectal, and thyroid cancers. Furthermore, inhibitors of PI3K (e.g., apitolisib, copanlisib), AKT (e.g., ipatasertib, perifosine), and mTOR (e.g., sirolimus, temsirolimus) exhibit promising efficacy against various cancers such as Invasive Breast Cancer, Lymphoma, Neoplasms, and Hematological malignancies. This review offers an overview of small molecule inhibitors targeting specific proteins within the RAS upstream and downstream signaling pathways in cancer.

Exosomal miRNAs: the tumor's trojan horse in selective metastasis

Organs of future metastasis are not passive receivers of circulating tumor cells, but are instead selectively and actively modified by the primary tumor before metastatic spread has even occurred. Tumors orchestrate a pre-metastatic program by conditioning distant organs to create microenvironments that foster the survival and proliferation of tumor cells before their arrival, thereby establishing pre-metastatic niches. Primary tumor-derived exosomes modulate these pre-metastatic niches, generating a permissive environment that facilitates the homing and expansion of tumor cells. Moreover, microRNAs have emerged as a key component of exosomal cargo, serving not only to induce the formation of pre-metastatic niches but also to prime these sites for the arrival and colonization of specific secondary tumor populations. Against this backdrop, this review endeavors to elucidate the impact of tumor-derived exosomal microRNAs on the genesis of their individualized pre-metastatic niches, with a view towards identifying novel means of specifying cancer metastasis and exploiting this phenomenon for cancer immunotherapy.

Role of Mitogen-Activated Protein (MAP) Kinase Pathways in Metabolic Diseases

Physiological processes that govern the normal functioning of mammalian cells are regulated by a myriad of signalling pathways. Mammalian mitogen-activated protein (MAP) kinases constitute one of the major signalling arms and have been broadly classified into four groups that include extracellular signal-regulated protein kinase (ERK), c-Jun N-terminal kinase (JNK), p38, and ERK5. Each signalling cascade is governed by a wide array of external and cellular stimuli, which play a critical part in mammalian cells in the regulation of various key responses, such as mitogenic growth, differentiation, stress responses, as well as inflammation. This evolutionarily conserved MAP kinase signalling arm is also important for metabolic maintenance, which is tightly coordinated via complicated mechanisms that include the intricate interaction of scaffold proteins, recognition through cognate motifs, action of phosphatases, distinct subcellular localisation, and even post-translational modifications. Aberration in the signalling pathway itself or their regulation has been implicated in the disruption of metabolic homeostasis, which provides a pathophysiological foundation in the development of metabolic syndrome. Metabolic syndrome is an umbrella term that usually includes a group of closely associated metabolic diseases such as hyperglycaemia, hyperlipidaemia, and hypertension. These risk factors exacerbate the development of obesity, diabetes, atherosclerosis, cardiovascular diseases, and hepatic diseases, which have accounted for an increase in the worldwide morbidity and mortality rate. This review aims to summarise recent findings that have implicated MAP kinase signalling in the development of metabolic diseases, highlighting the potential therapeutic targets of this pathway to be investigated further for the attenuation of these diseases.

Ginsenoside Rg1 promotes β‑amyloid peptide degradation through inhibition of the ERK/PPARγ phosphorylation pathway in an Alzheimer's disease neuronal model

β-Amyloid peptide (Aβ) deposition in the brain is an important pathological change in Alzheimer's disease (AD). Insulin-degrading enzyme (IDE), which is regulated transcriptionally by peroxisome proliferator-activated receptor γ (PPARγ), is able to proteolyze Aβ. One of the members of the MAPK family, ERK, is able to mediate the phosphorylation of PPARγ at Ser112, thereby inhibiting its transcriptional activity. Ginsenoside Rg1 is one of the active ingredients in the natural medicine ginseng and has inhibitory effects on Aβ production. The present study was designed to investigate whether ginsenoside Rg1 is able to affect the regulation of PPARγ based on the expression of its target gene, IDE, and whether it is able to promote Aβ degradation via inhibition of the ERK/PPARγ phosphorylation pathway. In the present study, primary cultured rat hippocampal neurons were treated with Aβ1-42, ginsenoside Rg1 and the ERK inhibitor PD98059, and subsequently TUNEL staining was used to detect the level of neuronal apoptosis. ELISA was subsequently employed to detect the intra- and extracellular Aβ1-42 levels, immunofluorescence staining and western blotting were used to detect the translocation of ERK from the cytoplasm to the nucleus, immunofluorescence double staining was used to detect the co-expression of ERK and PPARγ, and finally, western blotting was used to detect the phosphorylation of PPARγ at Ser112 and IDE expression. The results demonstrated that ginsenoside Rg1 or PD98059 were able to inhibit primary cultured hippocampal neuron apoptosis induced by Aβ1-42 treatment, reduce the levels of intra- and extraneuronal Aβ1-42 and inhibit the translocation of ERK from the cytoplasm to the nucleus. Furthermore, administration of ginsenoside Rg1 or PD98059 resulted in attenuated co-expression of ERK and PPARγ, inhibition of phosphorylation of PPARγ at Ser112 mediated by ERK and an increase in IDE expression. In addition, the effects when PD98059 to inhibit ERK followed by treatment with ginsenoside Rg1 were found to be more pronounced than those when using PD98059 alone. In conclusion, ginsenoside Rg1 was demonstrated to exert neuroprotective effects on AD via inhibition of the ERK/PPARγ phosphorylation pathway, which led to an increase in IDE expression, the promotion of Aβ degradation and the decrease of neuronal apoptosis. These results could provide a theoretical basis for the clinical application of ginsenoside Rg1 in AD.

ZYZ384 suppresses the growth of EGFR-mutant non-small cell lung cancer by activating JNK/MAPK signaling pathway

The emergency of tyrosine kinase inhibitors has remarkably enhanced the clinical outcomes of cancer therapy, especially the use of EGFR inhibitors for non-small cell lung cancer (NSCLC). However, acquired resistance is inevitable after 8-12 months treatment. New agents or treatments are urgently required to resolve this problem. In this study, we identified that compound ZYZ384 can selectively inhibit the growth of gefitinib-resistant (G-R) lung cancer cells, without affecting that of normal lung epithelial cells. ZYZ384 induced G2 arrest in G-R NSCLC cells, decreasing the expression of Cyclin B1 and increasing the expression of P21. Meanwhile, ZYZ384 also induced apoptosis in NSCLC cells and correspondingly increased the expression of cleaved Caspase 3, 8, and 9 proteins. The expression of p-JNK, p-P38, and p-ERK were also increased in H1975 NSCLC cells treated with ZYZ384. Finally, we observed that the JNK inhibitor effectively reversed the pro-apoptotic effect of ZYZ384. In conclusion, ZYZ384 is a potential therapeutic agent to inhibit the growth of NSCLCs with EGFR mutations through activating JNK, which will help the development of related anticancer drugs.

Exploration of the Shared Hub Genes and Biological Mechanism in Osteoporosis and Type 2 Diabetes Mellitus based on Machine Learning

A substantial amount of evidence suggests a close relationship between osteoporosis (OP) and Type 2 Diabetes Mellitus (T2DM), but the mechanisms involved remain unknown. Therefore, we conducted this study with the aim of screening for hub genes common to both diseases and conducting a preliminary exploration of common regulatory mechanisms. In the present study, we first screened genes significantly associated with OP and T2DM by the univariate logistic regression algorithm. And then, based on cross-analysis and random forest algorithm, we obtained three hub genes (ACAA2, GATAD2A, and VPS35) and validated the critical roles and predictive performance of the three genes in both diseases by differential expression analysis, receiver operating characteristic (ROC) curves, and genome wide association study (GWAS) analysis. Finally, based on gene set enrichment analysis (GSEA) and the construction of the miRNA-mRNA regulatory network, we conducted a preliminary exploration of the co-regulatory mechanisms of three hub genes in two diseases. In conclusion, this study provides promising biomarkers for predicting and treating both diseases and offers novel directions for exploring the common regulatory mechanisms of both diseases.

Gαs is dispensable for β-arrestin coupling but dictates GRK selectivity and is predominant for gene expression regulation by β2-adrenergic receptor

β-arrestins play a key role in G protein-coupled receptor (GPCR) internalization, trafficking, and signaling. Whether β-arrestins act independently of G protein-mediated signaling has not been fully elucidated. Studies using genome-editing approaches revealed that whereas G proteins are essential for mitogen-activated protein kinase activation by GPCRs., β-arrestins play a more prominent role in signal compartmentalization. However, in the absence of G proteins, GPCRs may not activate β-arrestins, thereby limiting the ability to distinguish G protein from β-arrestin-mediated signaling events. We used β2-adrenergic receptor (β2AR) and its β2AR-C tail mutant expressed in human embryonic kidney 293 cells wildtype or CRISPR-Cas9 gene edited for Gαs, β-arrestin1/2, or GPCR kinases 2/3/5/6 in combination with arrestin conformational sensors to elucidate the interplay between Gαs and β-arrestins in controlling gene expression. We found that Gαs is not required for β2AR and β-arrestin conformational changes, β-arrestin recruitment, and receptor internalization, but that Gαs dictates the GPCR kinase isoforms involved in β-arrestin recruitment. By RNA-Seq analysis, we found that protein kinase A and mitogen-activated protein kinase gene signatures were activated by stimulation of β2AR in wildtype and β-arrestin1/2-KO cells but absent in Gαs-KO cells. These results were validated by re-expressing Gαs in the corresponding KO cells and silencing β-arrestins in wildtype cells. These findings were extended to cellular systems expressing endogenous levels of β2AR. Overall, our results support that Gs is essential for β2AR-promoted protein kinase A and mitogen-activated protein kinase gene expression signatures, whereas β-arrestins initiate signaling events modulating Gαs-driven nuclear transcriptional activity.

Non-Excitatory Amino Acids, Melatonin, and Free Radicals: Examining the Role in Stroke and Aging

The aim of this review is to explore the relationship between melatonin, free radicals, and non-excitatory amino acids, and their role in stroke and aging. Melatonin has garnered significant attention in recent years due to its diverse physiological functions and potential therapeutic benefits by reducing oxidative stress, inflammation, and apoptosis. Melatonin has been found to mitigate ischemic brain damage caused by stroke. By scavenging free radicals and reducing oxidative damage, melatonin may help slow down the aging process and protect against age-related cognitive decline. Additionally, non-excitatory amino acids have been shown to possess neuroprotective properties, including antioxidant and anti-inflammatory in stroke and aging-related conditions. They can attenuate oxidative stress, modulate calcium homeostasis, and inhibit apoptosis, thereby safeguarding neurons against damage induced by stroke and aging processes. The intracellular accumulation of certain non-excitatory amino acids could promote harmful effects during hypoxia-ischemia episodes and thus, the blockade of the amino acid transporters involved in the process could be an alternative therapeutic strategy to reduce ischemic damage. On the other hand, the accumulation of free radicals, specifically mitochondrial reactive oxygen and nitrogen species, accelerates cellular senescence and contributes to age-related decline. Recent research suggests a complex interplay between melatonin, free radicals, and non-excitatory amino acids in stroke and aging. The neuroprotective actions of melatonin and non-excitatory amino acids converge on multiple pathways, including the regulation of calcium homeostasis, modulation of apoptosis, and reduction of inflammation. These mechanisms collectively contribute to the preservation of neuronal integrity and functions, making them promising targets for therapeutic interventions in stroke and age-related disorders.

Climate has contributed to population diversification of Daphnia galeata across Eurasia

Climate is a fundamental abiotic factor that plays a key role in driving the evolution, distribution and population diversification of species. However, there have been few investigations of genomic signatures of adaptation to local climatic conditions in cladocerans. Here, we have provided the first high-quality chromosome-level genome assembly (~143 Mb, scaffold N50 12.6 Mb) of the waterflea, Daphnia galeata, and investigated genomic variation in 22 populations from Central Europe and Eastern China. Our ecological-niche models suggested that the historic distribution of D. galeata in Eurasia was significantly affected by Quaternary climate fluctuations. We detected pronounced genomic and morphometric divergences between European and Chinese D. galeata populations. Such divergences could be partly explained by genomic signatures of thermal adaptation to distinct climate regimes: a set of candidate single-nucleotide polymorphisms (SNPs) potentially associated with climate were detected. These SNPs were in genes significantly enriched in the Gene ontology terms "determination of adult lifespan" and "translation repressor activity", and especially, mthl5 and SOD1 involved in the IIS pathway, and EIF4EBP2 involved in the target of the rapamycin signalling pathway. Our study indicates that certain alleles might be associated with particular temperature regimes, playing a functional role in shaping the population structure of D. galeata at a large geographical scale. These results highlight the potential role of molecular variation in the response to climate variation, in the context of global climate change.

Breast stiffness, a risk factor for cancer and the role of radiology for diagnosis

Over the last five decades, breast density has been associated with increased risk of developing breast cancer. Mammographically dense breasts are considered those belonging to the heterogeneously dense breasts, and extremely dense breasts subgroups according to the American College of Radiology's Breast Imaging Reporting and Data System (BI-RADS). There is a statistically significant correlation between the increased mammographic density and the presence of more glandular tissue alone. However, the strength of this correlation is weak. Although the mechanisms driving breast density-related tumor initiation and progression are still unknown, there is evidence suggesting that certain molecular pathways participating in epithelial-stromal interactions may play a pivotal role in the deposition of fibrillar collagen, increased matrix stiffness, and cell migration that favor breast density and carcinogenesis. This article describes these molecular mechanisms as potential "landscapers" for breast density-related cancer. We also introduce the term "Breast Compactness" to reflect collagen density of breast tissue on chest CT scan and the use of breast stiffness measurements as imaging biomarkers for breast cancer screening and risk stratification.

Voltage-Gated Na+ Channels in Alzheimer's Disease: Physiological Roles and Therapeutic Potential

Alzheimer's disease (AD) is the most common cause of dementia and is classically characterized by two major histopathological abnormalities: extracellular plaques composed of amyloid beta (Aβ) and intracellular hyperphosphorylated tau. Due to the progressive nature of the disease, it is of the utmost importance to develop disease-modifying therapeutics that tackle AD pathology in its early stages. Attenuation of hippocampal hyperactivity, one of the earliest neuronal abnormalities observed in AD brains, has emerged as a promising strategy to ameliorate cognitive deficits and abate the spread of neurotoxic species. This aberrant hyperactivity has been attributed in part to the dysfunction of voltage-gated Na+ (Nav) channels, which are central mediators of neuronal excitability. Therefore, targeting Nav channels is a promising strategy for developing disease-modifying therapeutics that can correct aberrant neuronal phenotypes in early-stage AD. This review will explore the role of Nav channels in neuronal function, their connections to AD pathology, and their potential as therapeutic targets.

Vemurafenib improves muscle histopathology in a mouse model of LAMA2-related congenital muscular dystrophy

Laminin-α2-related congenital muscular dystrophy (LAMA2-CMD) is a neuromuscular disease affecting around 1-9 in 1,000,000 children. LAMA2-CMD is caused by mutations in the LAMA2 gene resulting in the loss of laminin-211/221 heterotrimers in skeletal muscle. LAMA2-CMD patients exhibit severe hypotonia and progressive muscle weakness. Currently, there is no effective treatment for LAMA2-CMD and patients die prematurely. The loss of laminin-α2 results in muscle degeneration, defective muscle repair and dysregulation of multiple signaling pathways. Signaling pathways that regulate muscle metabolism, survival and fibrosis have been shown to be dysregulated in LAMA2-CMD. As vemurafenib is a US Food and Drug Administration (FDA)-approved serine/threonine kinase inhibitor, we investigated whether vemurafenib could restore some of the serine/threonine kinase-related signaling pathways and prevent disease progression in the dyW-/- mouse model of LAMA2-CMD. Our results show that vemurafenib reduced muscle fibrosis, increased myofiber size and reduced the percentage of fibers with centrally located nuclei in dyW-/- mouse hindlimbs. These studies show that treatment with vemurafenib restored the TGF-β/SMAD3 and mTORC1/p70S6K signaling pathways in skeletal muscle. Together, our results indicate that vemurafenib partially improves histopathology but does not improve muscle function in a mouse model of LAMA2-CMD.

Molecular Insights of MAP4K4 Signaling in Inflammatory and Malignant Diseases

Mitogen-activated protein kinase (MAPK) cascades are crucial in extracellular signal transduction to cellular responses. The classical three-tiered MAPK cascades include signaling through MAP kinase kinase kinase (MAP3K) that activates a MAP kinase kinase (MAP2K), which in turn induces MAPK activation and downstream cellular responses. The upstream activators of MAP3K are often small guanosine-5'-triphosphate (GTP)-binding proteins, but in some pathways, MAP3K can be activated by another kinase, which is known as a MAP kinase kinase kinase kinase (MAP4K). MAP4K4 is one of the widely studied MAP4K members, known to play a significant role in inflammatory, cardiovascular, and malignant diseases. The MAP4K4 signal transduction plays an essential role in cell proliferation, transformation, invasiveness, adhesiveness, inflammation, stress responses, and cell migration. Overexpression of MAP4K4 is frequently reported in many cancers, including glioblastoma, colon, prostate, and pancreatic cancers. Besides its mainstay pro-survival role in various malignancies, MAP4K4 has been implicated in cancer-associated cachexia. In the present review, we discuss the functional role of MAP4K4 in malignant/non-malignant diseases and cancer-associated cachexia and its possible use in targeted therapy.

miR-126 mitigates the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by targeting the ERK1/2 and Bcl-2 pathways

Human bone marrow mesenchymal stem cells (hBMMSCs) are a promising cell source for bone engineering owing to their high potential to differentiate into osteoblasts. The objective of the present study is to assess microRNA-126 (miR-126) and examine its effects on the osteogenic differentiation of hBMMSCs. In this study, we investigate the role of miR-126 in the progression of osteogenic differentiation (OD) as well as the apoptosis and inflammation of hBMMSCs during OD induction. OD is induced in hBMMSCs, and matrix mineralization along with other OD-associated markers are evaluated by Alizarin Red S (AR) staining and quantitative PCR (qPCR). Gain- and loss-of-function studies are performed to demonstrate the role of miR-126 in the OD of hBMMSCs. Flow cytometry and qPCR-based cytokine expression studies are performed to investigate the effect of miR-126 on the apoptosis and inflammation of hBMMSCs. The results indicate that miR-126 expression is downregulated during the OD of hBMMSCs. Gain- and loss-of function assays reveal that miR-126 upregulation inhibits the differentiation of hBMMSCs into osteoblasts, whereas the downregulation of miR-126 promotes hBMMSC differentiation, as assessed by the determination of osteogenic genes and alkaline phosphatase activity. Furthermore, the miR-126 level is positively correlated with the production of inflammatory cytokines and apoptotic cell death. Additionally, our results suggest that miR-126 negatively regulates not only B-cell lymphoma 2 (Bcl-2) expression but also the phosphorylation of extracellular signal‑regulated protein kinase (ERK) 1/2. Moreover, restoring ERK1/2 activity and upregulating Bcl-2 expression counteract the miR-126-mediated suppression of OD in hBMMSCs by promoting inflammation and apoptosis, respectively. Overall, our findings suggest a novel molecular mechanism relevant to the differentiation of hBMMSCs into osteoblasts, which can potentially facilitate bone formation by counteracting miR-126-mediated suppression of ERK1/2 activity and Bcl-2 expression.

MicroRNAs and MAPKs: Evidence of These Molecular Interactions in Alzheimer's Disease

Alzheimer's disease (AD) is a neurodegenerative disorder known to be the leading cause of dementia worldwide. Many microRNAs (miRNAs) were found deregulated in the brain or blood of AD patients, suggesting a possible key role in different stages of neurodegeneration. In particular, mitogen-activated protein kinases (MAPK) signaling can be impaired by miRNA dysregulation during AD. Indeed, the aberrant MAPK pathway may facilitate the development of amyloid-beta (Aβ) and Tau pathology, oxidative stress, neuroinflammation, and brain cell death. The aim of this review was to describe the molecular interactions between miRNAs and MAPKs during AD pathogenesis by selecting evidence from experimental AD models. Publications ranging from 2010 to 2023 were considered, based on PubMed and Web of Science databases. According to obtained data, several miRNA deregulations may regulate MAPK signaling in different stages of AD and conversely. Moreover, overexpressing or silencing miRNAs involved in MAPK regulation was seen to improve cognitive deficits in AD animal models. In particular, miR-132 is of particular interest due to its neuroprotective functions by inhibiting Aβ and Tau depositions, as well as oxidative stress, through ERK/MAPK1 signaling modulation. However, further investigations are required to confirm and implement these promising results.

Bioactivity, Molecular Mechanism, and Targeted Delivery of Flavonoids for Bone Loss

Skeletal disabilities are a prominent burden on the present population with an increasing life span. Advances in osteopathy have provided various medical support for bone-related diseases, including pharmacological and prosthesis interventions. However, therapeutics and post-surgery complications are often reported due to side effects associated with modern-day therapies. Thus, therapies utilizing natural means with fewer toxic or other side effects are the key to acceptable interventions. Flavonoids constitute a class of bioactive compounds found in dietary supplements, and their pharmacological attributes have been well appreciated. Recently, flavonoids' role is gaining renowned interest for its effect on bone remodeling. A wide range of flavonoids has been found to play a pivotal role in the major bone signaling pathways, such as wingless-related integration site (Wnt)/β-catenin, bone morphogenetic protein (BMP)/transforming growth factor (TGF)-β, mitogen-activated protein kinase (MAPK), etc. However, the reduced bioavailability and the absorption of flavonoids are the major limitations inhibiting their use against bone-related complications. Recent utilization of nanotechnological approaches and other delivery methods (biomaterial scaffolds, micelles) to target and control release can enhance the absorption and bioavailability of flavonoids. Thus, we have tried to recapitulate the understanding of the role of flavonoids in regulating signaling mechanisms affecting bone remodeling and various delivery methods utilized to enhance their therapeutical potential in treating bone loss.

Research progress of p38 as a new therapeutic target against morphine tolerance and the current status of therapy of morphine tolerance

With the development of the medical industry, new painkillers continue to appear in people's field of vision, but so far no painkiller can replace morphine. While morphine has a strong analgesic effect, it is also easy to produce pain sensitivity and tolerance. Due to the great inter-individual differences in patient responses, there are few clear instructions on how to optimise morphine administration regimens, which complicates clinicians' treatment strategies and limits the effectiveness of morphine in long-term pain therapy. P38MAPK is a key member of the MAPK family. Across recent years, it has been discovered that p38MAPK rises dramatically in a wide range of morphine tolerance animal models. Morphine tolerance can be reduced or reversed by inhibiting p38MAPK. However, the role and specific mechanism of p38MAPK are not clear. In this review, we synthesise the relevant findings, highlight the function and potential mechanism of p38MAPK in morphine tolerance, as well as the present status and efficacy of morphine tolerance therapy, and underline the future promise of p38MAPK targeted morphine tolerance treatment.

Diabetic Neuropathy: Review on Molecular Mechanisms

Diabetic mellitus is a worldwide endocrine and metabolic disorder with insulin insensitivity or deficiency or both whose prevalence could rise up to 592 million by 2035. Consistent hyperglycemia leads to one of the most common comorbidities like Diabetic Peripheral Neuropathy (DPN). DPN is underlined with unpleasant sensory experience, such as tingling and burning sensation, hyperalgesia, numbness, etc. Globally, 50-60% of the diabetic population is suffering from such symptoms as microvascular complications. Consistent hyperglycemia during DM causes activation/inhibition of various pathways playing important role in the homeostasis of neurons and other cells. Disruption of these pathways results into apoptosis and mitochondrial dysfunctions, causing neuropathy. Among these, pathways like Polyol and PARP are some of the most intensively studied ones whereas those like Wnt pathway, Mitogen activated protein kinase (MAPK), mTOR pathway are comparatively newly discovered. Understanding of these pathways and their role in pathophysiology of DN underlines a few molecules of immense therapeutic value. The inhibitors or activators of these molecules can be of therapeutic importance in the management of DPN. This review, hence, focuses on these underlying molecular mechanisms intending to provide therapeutically effective molecular targets for the treatment of DPN.

Dual-Specificity Protein Phosphatase 4 (DUSP4) Overexpression Improves Learning Behavior Selectively in Female 5xFAD Mice, and Reduces β-Amyloid Load in Males and Females

Recent multiscale network analyses of banked brains from subjects who died of late-onset sporadic Alzheimer's disease converged on VGF (non-acronymic) as a key hub or driver. Within this computational VGF network, we identified the dual-specificity protein phosphatase 4 (DUSP4) [also known as mitogen-activated protein kinase (MAPK) phosphatase 2] as an important node. Importantly, DUSP4 gene expression, like that of VGF, is downregulated in postmortem Alzheimer's disease (AD) brains. We investigated the roles that this VGF/DUSP4 network plays in the development of learning behavior impairment and neuropathology in the 5xFAD amyloidopathy mouse model. We found reductions in DUSP4 expression in the hippocampi of male AD subjects, correlating with increased CDR scores, and in 4-month-old female and 12-18-month-old male 5xFAD hippocampi. Adeno-associated virus (AAV5)-mediated overexpression of DUSP4 in 5xFAD mouse dorsal hippocampi (dHc) rescued impaired Barnes maze performance in females but not in males, while amyloid loads were reduced in both females and males. Bulk RNA sequencing of the dHc from 5-month-old mice overexpressing DUSP4, and Ingenuity Pathway and Enrichr analyses of differentially expressed genes (DEGs), revealed that DUSP4 reduced gene expression in female 5xFAD mice in neuroinflammatory, interferon-gamma (IFNγ), programmed cell death protein-ligand 1/programmed cell death protein 1 (PD-L1/PD-1), and extracellular signal-regulated kinase (ERK)/MAPK pathways, via which DUSP4 may modulate AD phenotype with gender-specificity.

The endoplasmic reticulum participated in drug metabolic toxicity

Covalent binding of reactive metabolites formed by drug metabolic activation with biological macromolecules is considered to be an important mechanism of drug metabolic toxicity. Recent studies indicate that the endoplasmic reticulum (ER) could play an important role in drug toxicity by participating in the metabolic activation of drugs and could be a primarily attacked target by reactive metabolites. In this article, we summarize the generation and mechanism of reactive metabolites in ER stress and their associated cell death and inflammatory cascade, as well as the systematic modulation of unfolded protein response (UPR)-mediated adaptive pathways.

Protein kinases in natural versus drug reward

Natural and drug rewards act on the same neural pathway, the mesolimbic dopaminergic system. In brain regions such as the nucleus accumbens and ventral tegmental area, drugs of abuse-induced stimulation of signaling pathways can lead to synaptic reshaping within this system. This is believed to be underlying the maladaptive alterations in behaviors associated with addiction. In this review, we discuss animal studies disclosing the implication of several protein kinases, namely protein kinase A (PKA), extracellular signal regulated kinase (ERK) mitogen-activated protein kinases (MAPK), p38 MAPK, and calcium/calmodulin-dependent kinase II (CaMKII), in reward-related brain regions in drug and natural reward. Furthermore, we refer to studies that helped pave the way toward a better understanding of the neurobiology underlying non-drug and drug reward through genetic deletion or brain region-specific pharmacological inhibition of these kinases. Whereas the role of kinases in drug reward has been extensively studied, their implication in natural reward, such as positive social interaction, is less investigated. Discovering molecular candidates, recruited specifically by drug versus natural rewards, can promote the identification of novel targets for the pharmacological treatment of addiction with less off-target effects and being effective when used combined with behavioral-based therapies.

Combinatorial approaches of nanotherapeutics for inflammatory pathway targeted therapy of prostate cancer

Prostate cancer (PC) is the most prevalent male urogenital cancer worldwide. PC patients presenting an advanced or metastatic cancer succumb to the disease, even after therapeutic interventions including radiotherapy, surgery, androgen deprivation therapy (ADT), and chemotherapy. One of the hallmarks of PC is evading immune surveillance and chronic inflammation, which is a major challenge towards designing effective therapeutic formulations against PC. Chronic inflammation in PC is often characterized by tumor microenvironment alterations, epithelial-mesenchymal transition and extracellular matrix modifications. The inflammatory events are modulated by reactive nitrogen and oxygen species, inflammatory cytokines and chemokines. Major signaling pathways in PC includes androgen receptor, PI3K and NF-κB pathways and targeting these inter-linked pathways poses a major therapeutic challenge. Notably, many conventional treatments are clinically unsuccessful, due to lack of targetability and poor bioavailability of the therapeutics, untoward toxicity and multidrug resistance. The past decade witnessed an advancement of nanotechnology as an excellent therapeutic paradigm for PC therapy. Modern nanovectorization strategies such as stimuli-responsive and active PC targeting carriers offer controlled release patterns and superior anti-cancer effects. The current review initially describes the classification, inflammatory triggers and major inflammatory pathways of PC, various PC treatment strategies and their limitations. Subsequently, recent advancement in combinatorial nanotherapeutic approaches, which target PC inflammatory pathways, and the mechanism of action are discussed. Besides, the current clinical status and prospects of PC homing nanovectorization, and major challenges to be addressed towards the advancement PC therapy are also addressed.

p38-dependent c-Jun degradation contributes to reduced PGE2 production in sodium orthovanadate-treated macrophages

In particular, the phenomenon of c-Jun degradation within the inflammatory response has not yet been fully analyzed. In order to verify this, we investigated LPS-stimulated murine macrophages pre-treated with sodium orthovanadate (SO) in order to uncover the regulatory mechanisms of the MAPKs which regulate c-Jun degradation within the inflammatory response. Through our study, we found that SO suppressed the production of prostaglandin E₂ (PGE₂) and the expression of COX-2 in LPS-stimulated RAW264.7 cells. Additionally, SO decreased total c-Jun levels, without altering the amount of mRNA, although the phospho-levels of p38, ERK, and JNK were strongly enhanced. Through the usage of selective MAPK inhibitors, and knockdown and overexpression strategies, p38 was revealed to be a major MAPK which regulates c-Jun degradation. Further analysis indicates that the phosphorylation of p38 is a determinant for c-Jun degradation, and is sufficient to induce ubiquitination-dependent c-Jun degradation, recovered through MG132 treatment. Therefore, our results suggest that the hyperphosphorylation of p38 by SO contributes to c-Jun degradation, which is linked to the suppression of PGE₂ secretion in inflammatory responses; and thus, finding drugs to increase p38 activity could be a novel strategy for the development of anti-inflammatory drugs.

Molecular mechanisms of Marine-Derived Natural Compounds as photoprotective strategies

Excessive exposure of the skin to ultraviolet radiation (UVR) causes oxidative stress, inflammation, immunosuppression, apoptosis, and changes in the extracellular matrix, which lead to the development of photoaging and photodamage of skin. At the molecular level, these pathological changes are mainly caused by the activation of related protein kinases and downstream transcription pathways, the increase of matrix metalloproteinase, the formation of reactive oxygen species, and the combined action of cytokines and inflammatory mediators. At present, the photostability, toxicity, and damage to marine ecosystems of most sun protection products in the market have affected their efficacy and safety. Another way is to use natural products produced by various marine species. Marine organisms have evolved a variety of molecular strategies to protect themselves from the harmful effects of ultraviolet radiation, and their unique chemicals have attracted more and more attention in the research of photoprotection and photoaging resistance. This article provides an extensive description of the recent literature on the potential of Marine-Derived Natural Compounds (MDNCs) as photoprotective and photoprotective agents. It reviews the positive effects of MDNCs in counteracting UV-induced oxidative stress, inflammation, DNA damage, apoptosis, immunosuppression, and extracellular matrix degradation. Some MDNCs have the potential to develop feasible solutions for related phenomena, such as photoaging and photodamage caused by UVR.

Luteolin Pretreatment Attenuates Hepatic Ischemia-Reperfusion Injury in Mice by Inhibiting Inflammation, Autophagy, and Apoptosis via the ERK/PPARα Pathway

Hepatic ischemia-reperfusion (IR) injury is a clinically significant process that frequently occurs in liver transplantation, partial hepatectomy, and hemorrhagic shock. The aim of this study was to explore the effectiveness of luteolin in hepatic IR injury and the underlying mechanism. BALB/c mice were randomly divided into six groups, including normal controls (NC), luteolin (50 mg/kg), sham procedure, IR+25 mg/kg luteolin, and IR+50 mg/kg luteolin group. Serum and tissue samples were collected at 6 and 24 h after reperfusion to assay liver enzymes, inflammatory factors, expression of proteins associated with apoptosis and autophagy, and factors associated with the extracellular signal-regulated kinase/peroxisome proliferator-activated receptor alpha (ERK/PPARα) pathway. Luteolin preconditioning decreased hepatocyte injury caused by ischemia-reperfusion, downregulated inflammatory factors, and inhibited apoptosis and autophagy. Luteolin also inhibited ERK phosphorylation and activated PPARα.

Combining Recombinase-Mediated Cassette Exchange Strategy with Quantitative Proteomic and Phosphoproteomic Analyses to Inspect Intracellular Functions of the Tumor Suppressor Galectin-4 in Colorectal Cancer Cells

Galectin-4 (Gal4) has been suggested to function as a tumor suppressor in colorectal cancer (CRC). In order to systematically explore its function in CRC, we established a CRC cell line where Gal4 expression can be regulated via the doxycycline (dox)-inducible expression of a single copy wildtype LGALS4 transgene generated by recombinase-mediated cassette exchange (RMCE). Using this model and applying in-depth proteomic and phosphoproteomic analyses, we systematically screened for intracellular changes induced by Gal4 expression. Overall, 3083 cellular proteins and 2071 phosphosites were identified and quantified, of which 1603 could be matched and normalized to their protein expression levels. A bioinformatic analysis revealed that most of the regulated proteins and phosphosites can be localized in the nucleus and are categorized as nucleic acid-binding proteins. The top candidates whose expression was modulated by Gal4 are PURB, MAPKAPK3, BTF3 and BCAR1, while the prime candidates with altered phosphorylation included ZBTB7A, FOXK1, PURB and CK2beta. In order to validate the (phospho)proteomic data, we confirmed these candidates by a radiometric metabolic-labelling and immunoprecipitation strategy. All candidates exert functions in the transcriptional or translational control, indicating that Gal4 might be involved in these processes by affecting the expression or activity of these proteins.

The Signaling Pathways and Targets of Natural Compounds from Traditional Chinese Medicine in Treating Ischemic Stroke

Ischemic stroke (IS) is a common neurological disorder associated with high disability rates and mortality rates. At present, recombinant tissue plasminogen activator (r-tPA) is the only US(FDA)-approved drug for IS. However, due to the narrow therapeutic window and risk of intracerebral hemorrhage, r-tPA is currently used in less than 5% of stroke patients. Natural compounds have been widely used in the treatment of IS in China and have a wide range of therapeutic effects on IS by regulating multiple targets and signaling pathways. The keywords "ischemia stroke, traditional Chinese Medicine, Chinese herbal medicine, natural compounds" were used to search the relevant literature in PubMed and other databases over the past five years. The results showed that JAK/STAT, NF-κB, MAPK, Notch, Nrf2, and PI3K/Akt are the key pathways, and SIRT1, MMP9, TLR4, HIF-α are the key targets for the natural compounds from traditional Chinese medicine in treating IS. This study aims to update and summarize the signaling pathways and targets of natural compounds in the treatment of IS, and provide a base of information for the future development of effective treatments for IS.

Enhanced proliferation and differentiation of human mesenchymal stem cells in the gravity-controlled environment

BACKGROUND

Human bone marrow mesenchymal stem cells (hMSCs) present a promising cell source with a potential to be used for curing various intractable diseases. And it is expected that the development of regenerative medicine employing cell-based therapy would be significantly accelerated when such methods are established. For that, powerful methods for selective growth and differentiation of hMSCs should be developed.

METHODS

We developed an efficient method for hMSC proliferation and differentiation into osteoblasts and adipocytes using gravity-controlled environments.

RESULTS

The results indicate that the average doubling time of hMSCs cultured in a regular maintenance medium under microgravity conditions (0.001 G) was 1.5 times shorter than that of cells cultured under natural gravity conditions (1.0 G). Furthermore, 99.2% of cells grown in the microgravity environment showed the expression of hMSC markers, as indicated by flow cytometry analysis. Osteogenic and adipogenic differentiation of hMSCs expanded in the microgravity environment was enhanced under microgravity and hypergravity conditions, respectively, as evidenced by the downregulation of hMSC markers and upregulation of osteoblast and adipocyte markers, respectively. Most cells differentiated into osteoblasts in the microgravity environment after 14 days (~80%) and to adipocytes in the hypergravity environment after 12 days (~90%).

CONCLUSIONS

Our results indicate that hMSC proliferation and selective differentiation into specific cell lineages could be promoted under microgravity or hypergravity conditions, suggesting that cell culture in the gravity-controlled environment is a useful method to obtain cell preparations for potential clinical applications.

Substrates of the MAPK Slt2: Shaping Yeast Cell Integrity

The cell wall integrity (CWI) MAPK pathway of budding yeast Saccharomyces cerevisiae is specialized in responding to cell wall damage, but ongoing research shows that it participates in many other stressful conditions, suggesting that it has functional diversity. The output of this pathway is mainly driven by the activity of the MAPK Slt2, which regulates important processes for yeast physiology such as fine-tuning of signaling through the CWI and other pathways, transcriptional activation in response to cell wall damage, cell cycle, or determination of the fate of some organelles. To this end, Slt2 precisely phosphorylates protein substrates, modulating their activity, stability, protein interaction, and subcellular localization. Here, after recapitulating the methods that have been employed in the discovery of proteins phosphorylated by Slt2, we review the bona fide substrates of this MAPK and the growing set of candidates still to be confirmed. In the context of the complexity of MAPK signaling regulation, we discuss how Slt2 determines yeast cell integrity through phosphorylation of these substrates. Increasing data from large-scale analyses and the available methodological approaches pave the road to early identification of new Slt2 substrates and functions.

Dual-Specificity Phosphatase 14 Regulates Zebrafish Hair Cell Formation Through Activation of p38 Signaling Pathway

Most cases of acquired hearing loss are due to degeneration and subsequent loss of cochlear hair cells. Whereas mammalian hair cells are not replaced when lost, in zebrafish, they constantly renew and regenerate after injury. However, the molecular mechanism among this difference remains unknown. Dual-specificity phosphatase 14 (DUSP14) is an important negative modulator of mitogen-activated protein kinase (MAPK) signaling pathways. Our study was to investigate the effects of DUSP14 on supporting cell development and hair cell regeneration and explore the potential mechanism. Our results showed that dusp14 gene is highly expressed in zebrafish developing neuromasts and otic vesicles. Behavior analysis showed that dusp14 deficiency resulted in hearing defects in zebrafish larvae, which were reversed by dusp14 mRNA treatment. Moreover, knockdown of dusp14 gene caused a significant decrease in the number of neuromasts and hair cells in both neuromast and otic vesicle, mainly due to the inhibition of the proliferation of supporting cells, which results in a decrease in the number of supporting cells and ultimately in the regeneration of hair cells. We further found significant changes in a series of MAPK pathway genes through transcriptome sequencing analysis of dusp14-deficient zebrafish, especially mapk12b gene in p38 signaling. Additionally, inhibiting p38 signaling effectively rescued all phenotypes caused by dusp14 deficiency, including hair cell and supporting cell reduction. These results suggest that DUSP14 might be a key gene to regulate supporting cell development and hair cell regeneration and is a potential target for the treatment of hearing loss.

Reevaluation of the role of LIP-1 as an ERK/MPK-1 dual specificity phosphatase in the C. elegans germline

The RAS–ERK pathway is critical for metazoan development. In development, ERK activity is regulated by a balance of phosphorylation of ERK by MEK (MAPK kinase) and dephosphorylation by DUSPs (dual specificity phosphatases). LIP-1, a DUSP6/7 family member, was previously suggested to regulate MPK-1/ERK activity by dephosphorylating MPK-1 in the Caenorhabditis elegans germline, based on LIP-1's mutant phenotype in the germline and its DUSP role in vulval development. However, our investigations demonstrate that LIP-1 does not function as an MPK-1 DUSP in the germline and likely regulates germline functions through distinct targets. Our results present a cautionary note about misinterpreting similar mutant phenotypes caused by mutations in different genes and assuming that genes function similarly in different tissues.

The fidelity of a signaling pathway depends on its tight regulation in space and time. Extracellular signal-regulated kinase (ERK) controls wide-ranging cellular processes to promote organismal development and tissue homeostasis. ERK activation depends on a reversible dual phosphorylation on the TEY motif in its active site by ERK kinase (MEK) and dephosphorylation by DUSPs (dual specificity phosphatases). LIP-1, a DUSP6/7 homolog, was proposed to function as an ERK (MPK-1) DUSP in the Caenorhabditis elegans germline primarily because of its phenotype, which morphologically mimics that of a RAS/let-60 gain-of-function mutant (i.e., small oocyte phenotype). Our investigations, however, reveal that loss of lip-1 does not lead to an increase in MPK-1 activity in vivo. Instead, we show that loss of lip-1 leads to 1) a decrease in MPK-1 phosphorylation, 2) lower MPK-1 substrate phosphorylation, 3) phenocopy of mpk-1 reduction-of-function (rather than gain-of-function) allele, and 4) a failure to rescue mpk-1–dependent germline or fertility defects. Moreover, using diverse genetic mutants, we show that the small oocyte phenotype does not correlate with increased ectopic MPK-1 activity and that ectopic increase in MPK-1 phosphorylation does not necessarily result in a small oocyte phenotype. Together, these data demonstrate that LIP-1 does not function as an MPK-1 DUSP in the C. elegans germline. Our results caution against overinterpretation of the mechanistic underpinnings of orthologous phenotypes, since they may be a result of independent mechanisms, and provide a framework for characterizing the distinct molecular targets through which LIP-1 may mediate its several germline functions.

Proteomic analysis of hypothalamus in prepubertal and pubertal female goat

The functions of proteins at the onset of puberty in goats remain largely unexplored. To identify the proteins regulating puberty in goats, we analysed protein abundance and pathways in the hypothalamus of female goats. We applied tandem mass tag (TMT) labelling, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and parallel reaction monitoring (PRM) to examine hypothalamus of pubertal (cases; n = 3) and prepubertal (controls; n = 3) goats. We identified 5119 proteins, including 69 differentially abundant proteins (DAPs), of which 35 were upregulated and 34 were downregulated. Fourteen DAPs were randomly selected to verify these results using PRM, and the results were consistent with the TMT quantitative results. DAPs were enriched in MAPK signalling pathway, Ras signalling pathway, Autophagy-animal, Endocytosis, and PI3K/Akt/mTOR signalling pathway categories. These pathways are related to embryogenesis, cell proliferation, cell differentiation, and promoting the release of gonadotropin-releasing hormone (GnRH) in the hypothalamus. In particular, PDGFRβ and MAP3K7 occupied important locations in the protein-protein interaction network. The results demonstrate that DAPs and their related signalling pathways are crucial in regulating puberty in goats. However, further research is needed to explore the functions of DAPs and their pathways to provide new insights into the mechanism of puberty onset. SIGNIFICANCE: In domestic animals, reaching the age of puberty is an event that contributes significantly to lifetime reproductive potential. And the hypothalamus functions directly in the complex systemic changes that control puberty. Our study was the first TMT proteomics analysis on hypothalamus tissues of pubertal goats, which revealed the changes of protein and pathways that are related to the onset of puberty. We identified 69 DAPs, which were enriched in the MAPK signaling pathway, the Ras signaling pathway, and the IGF-1/PI3K/Akt/mTOR pathway, suggesting that these processes were probably involved in the onset of puberty.

Increased replication stress and R-loop accumulation in EGFRvIII-expressing glioblastoma present new therapeutic opportunities

Background

The oncogene epidermal growth factor receptor variant III (EGFRvIII) is expressed in approximately one-third of all glioblastomas (GBMs). So far it is not clear if EGFRvIII expression induces replication stress in GBM cells, which might serve as a therapeutical target.

Methods

Isogenetic EGFRvIII− and EGFRvIII+ cell lines with endogenous EGFRvIII expression were used. Markers of oncogenic and replication stress such as γH2AX, RPA, 53BP1, ATR, and CHK1 were analyzed using western blot, immunofluorescence, and flow cytometry. The DNA fiber assay was performed to analyze replication, transcription was measured by incorporation of EU, and genomic instability was investigated by micronuclei and CGH-Array analysis. Immunohistochemistry staining was used to detect replication stress markers and R-loops in human GBM samples.

Results

EGFRvIII+ cells exhibit an activated replication stress response, increased spontaneous DNA damage, elevated levels of single-stranded DNA, and reduced DNA replication velocity, which are all indicative characteristics of replication stress. Furthermore, we show here that EGFRvIII expression is linked to increased genomic instability. EGFRvIII-expressing cells display elevated RNA synthesis and R-loop formation, which could also be confirmed in EGFRvIII-positive GBM patient samples. Targeting replication stress by irinotecan resulted in increased sensitivity of EGFRvIII+ cells.

Conclusion

This study demonstrates that EGFRvIII expression is associated with increased replication stress, R-loop accumulation, and genomic instability. This might contribute to intratumoral heterogeneity but may also be exploited for individualized therapy approaches.

Harmine Hydrochloride Triggers G2/M Cell Cycle Arrest and Apoptosis in HCT116 Cells through ERK and PI3K/AKT/mTOR Signaling Pathways

Colorectal carcinoma (CRC) is one of the most common and aggressive malignant carcinomas. There is a pressing need to develop naturally derived novel drugs with minimal side effects for treatment of CRC. In this study, we aimed to investigate the anticancer effects of harmine hydrochloride (HMH), a hydrophilic and stable substance that is easily absorbed by tissues and similar to harmine, and the underlying mechanism of action in human CRC HCT116 cells. HMH inhibited the growth, colony formation, and migration ability of HCT116 cells. Additionally, HMH induced G2 cell cycle arrest by reducing expression of p-cdc2, cdc2, and cyclin B1, proteins that regulate the G2/M phase, and expression of Rb, a protein that regulates cell proliferation, in a dose-dependent manner. HMH mediated apoptosis by downregulating expression of apoptotic proteins (such as caspase-3, caspase-9, and PARP) and the anti-apoptotic protein Bcl-2 and by inducing expression of Bax, a pro-apoptotic protein. Furthermore, HMH reduced the levels of p-ERK, p-PI3K, p-AKT, and p-mTOR in HCT116 cells, and significantly inhibited p-ERK and p-AKT expression in cells treated with of HMH and PD98059, an ERK inhibitor, or LY294002, an AKT inhibitor (P<0.05 and P<0.01). These results demonstrate the inhibi-tory effect of HMH on cell proliferation and migration through inducing apoptosis by inhibiting ERK and PI3K/AKT/mTOR signaling pathways, indicating its potential therapeutic applications in CRC.

Extracellular vesicle-associated small heat shock proteins as therapeutic agents in neurodegenerative diseases and beyond

Increasing evidence points towards using extracellular vesicles (EVs) as a therapeutic strategy in neurodegenerative diseases such as multiple sclerosis, Parkinson's, and Alzheimer's disease. EVs are nanosized carriers that play an essential role in intercellular communication and cellular homeostasis by transporting an active molecular cargo, including a large variety of proteins. Recent publications demonstrate that small heat shock proteins (HSPBs) exhibit a beneficial role in neurodegenerative diseases. Moreover, it is defined that HSPBs target the autophagy and the apoptosis pathway, playing a prominent role in chaperone activity and cell survival. This review elaborates on the therapeutic potential of EVs and HSPBs, in particular HSPB1 and HSPB8, in neurodegenerative diseases. We conclude that EVs and HSPBs positively influence neuroinflammation, central nervous system (CNS) repair, and protein aggregation in CNS disorders. Moreover, we propose the use of HSPB-loaded EVs as advanced nanocarriers for the future development of neurodegenerative disease therapies.

Study on Mechanism of Jiawei Chaiqin Wendan Decoction in Treatment of Vestibular Migraine Based on Network Pharmacology and Molecular Docking Technology

Objective

To predict the main active ingredients, potential targets, and key pathways of Jiawei Chaiqin Wendan decoction treatment in vestibular migraine and explore possible mechanisms by network pharmacology and molecular docking technology.

Methods

The active ingredients and related targets of Jiawei Chaiqin Wendan decoction were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). The corresponding genes of the target were queried by UniProt database, and the “drug-compound-target-disease” network was constructed by Cytoscape 3.7.2 software. GO functional enrichment analysis and KEGG pathway enrichment analysis were carried out by R software and Bioconductor, and column chart and bubble chart were drawn by Prism software and OmicShare database for visualization. Finally, the mechanism and potential targets of Jiawei Chaiqin Wendan decoction in the treatment of vestibular migraine were predicted.

Results

The “drug-compound-target-disease” network contains 154 active ingredients and 85 intersection targets. The key targets include AKT1, IL6, MAPK3, VEGFA, EGFR, CASP3, EGF, MAPK1, PTGS2, and ESR1. A total of 1939 items were obtained by GO functional enrichment analysis (P < 0.05). KEGG pathway enrichment analysis screened 156 signal pathways (P < 0.05), involving PI3K-Akt signal pathway, AGE-RAGE signal pathway in diabetes complications, MAPK signal pathway, HIF-1 signal pathway, IL-17 signal pathway, etc. Molecular docking results showed that quercetin, luteolin, kaempferol, tanshinone IIa, wogonin, naringenin, nobiletin, dihydrotanshinlactone, beta-sitosterol, and salviolone have good affinity with core target proteins IL6, PTGS2, MAPK1, MAPK3, and CGRP1.

Conclusion

The active ingredients in Jiawei Chaiqin Wendan decoction may regulate the levels of inflammatory factors and neurotransmitters by acting on multiple targets such as IL6, MAPK3, MAPK1, and PTGS2, so as to play a therapeutic role in vestibular migraine.

Harmine Hydrochloride Mediates the Induction of G2/M Cell Cycle Arrest in Breast Cancer Cells by Regulating the MAPKs and AKT/FOXO3a Signaling Pathways

Breast cancer (BC) is one of the most common causes of death among women worldwide. Recently, interest in novel approaches for BC has increased by developing new drugs derived from natural products with reduced side effects. This study aimed to treat BC cells with harmine hydrochloride (HMH) to identify its anticancer effects and mechanisms. HMH treatment suppressed cell growth, migration, invasion, and colony formation in MCF-7 and MDA-MB-231 cells, regardless of the hormone signaling. It also reduced the phosphorylation of PI3K, AKT, and mTOR and increased FOXO3a expression. Additionally, HMH treatment increased p38 phosphorylation in MCF-7 cells and activated c-Jun N-terminal kinase (JNK) phosphorylation in MDA-MB-231 cells in a dose-dependent manner, where activated p38 and JNK increased FOXO3a expression. Activated FOXO3a increased the expression of p53, p21, and their downstream proteins, including p-cdc25, p-cdc2, and cyclin B1, to induce G2/M cell cycle arrest. Furthermore, HMH inhibited the PI3K/AKT/mTOR pathway by significantly reducing p-AKT expression in combination with LY294002, an AKT inhibitor. These results indicate that mitogen-activated protein kinases (MAPKs) and AKT/FOXO3a signaling pathways mediate the induction of cell cycle arrest following HMH treatment. Therefore, HMH could be a potential active compound for anticancer bioactivity in BC cells.

Cardiovascular protective effects of GLP-1:A focus on the MAPK signaling pathway

Cardiovascular and related metabolic diseases are significant global health challenges. Glucagon-like peptide 1 (GLP-1) is a brain-gut peptide secreted by ileal endocrine that is now an established drug target in type 2 diabetes (T2DM). GLP-1 targeting agents have been shown not only to treat T2DM, but also to exert cardiovascular protective effects through regulating multiple signaling pathways. The mitogen-activated protein kinase (MAPK) pathway, a common signal transduction pathway for transmitting extracellular signals to downstream effector molecules, is involved in regulating diverse cell physiological processes, including cell proliferation, differentiation, stress, inflammation, functional synchronization, transformation and apoptosis. The purpose of this review is to highlight the relationship between GLP-1 and cardiovascular disease (CVD), and discuss how GLP-1 exerts cardiovascular protective effects through MAPK signaling pathway. This review also discusses the future challenges in fully characterizing and evaluating the CVD protective effects of GLP-1 receptor agonists (GLP-1RA) at the cellular and molecular level. A better understanding of MAPK signaling pathway that are disregulated in CVD may aid in the design and development of promising GLP-1RA.

Regulation of Jun and Fos AP-1 transcription factors by JNK MAPKs signaling cascade in areca nut extract treated KB cells

The edible endosperm of Areca catechu is recognized as a potent carcinogenic agent either consumed alone or in combination with tobacco. Habitual chewing of areca nut leads to orally potential malignant disorders which are highly effective in malignant transformation and thereby lead to oral carcinogenesis. Human buccal epithelial KB carcinoma cells were used as an experimental cell system to inspect the mechanistic act of aqueous extract of areca nut on biochemical status and their implications on transcriptional activation of cancer signaling cascade that could possibly trigger numerous oncogenic players and finally decides the cells fate. Extract treated cells showed reduced viability with altered balance between oxidants and antioxidants which lead to redox status and which is known to distort various biological processes within the cell system. Results of RT-PCR demonstrated decreased expression of BCl2, cell cycle regulators along with Activator Protein -1 (AP-1) components. While Bax, p16 and p21 mRNAs showed increased expression in extract treated KB cells. Likewise, the translational levels of proliferation cell nuclear antigen (PCNA), tumor suppressor p53, retinoblastoma (Rb) and cyclin dependent kinase 4 (CDK4) were decreased along with AP-1 subunits (c-Jun/c-Fos) with increased protein levels of p21 in extract treated KB cells. Further, the downstream activation and regulation of AP-1 transcription factors could be through stress activated c-Jun - N terminal Kinase (JNK) Mitogen Activated Protein Kinases (MAPKs) which downregulated both Jun and Fos mRNA transcripts in areca nut extract exposed KB cells. Thus, outcome of the study provides insights into mechanistic path of pathogenesis of areca related disorders. Further, it could aid in designing new therapeutic modalities that specific targets these oncogenic players and help in disease management.

Antibacterial and osteogenic activities of clindamycin-releasing mesoporous silica/carboxymethyl chitosan composite hydrogels

Conventional treatment of jaw bone infection is often ineffective at controlling bacterial infection and enhancing bone regeneration. Biodegradable composite hydrogels comprised of carboxymethyl chitosan (CMCS) and clindamycin (CDM)-loaded mesoporous silica nanoparticles (MCM-41), possessing dual antibacterial activity and osteogenic potency, were developed in the present study. CDM was successfully loaded into both untreated and plasma-treated MCM-41 nanoparticles, denoted as (p)-MCM-41, followed by the incorporation of each of CDM-loaded (p)-MCM-41 into CMCS. The resulting CDM-loaded composite hydrogels, (p)-MCM-41-CDM-CMCS, demonstrated slow degradation rates (about 70% remaining weight after 14-day immersion), while the CDM-free composite hydrogel entirely disintegrated after 4-day immersion. The plasma treatment was found to improve drug loading capacity and slow down initial drug burst effect. The prolonged releases of CDM from both (p)-MCM-41-CDM-CMCS retained their antibacterial effect against Streptococcus sanguinis for at least 14 days in vitro. In vitro assessment of osteogenic activity showed that the CDM-incorporated composite hydrogel was cytocompatible to human mesenchymal stem cells (hMSCs) and induced hMSC mineralization via p38-dependent upregulated alkaline phosphatase activity. In conclusion, novel (p)-MCM-41-CDM-CMCS hydrogels with combined controlled release of CDM and osteogenic potency were successfully developed for the first time, suggesting their potential clinical benefit for treatment of intraoral bone infection.

Stress-activated kinases as therapeutic targets in pancreatic cancer

Pancreatic cancer is a dismal disease with high incidence and poor survival rates. With the aim to improve overall survival of pancreatic cancer patients, new therapeutic approaches are urgently needed. Protein kinases are key regulatory players in basically all stages of development, maintaining physiologic functions but also being involved in pathogenic processes. c-Jun N-terminal kinases (JNK) and p38 kinases, representatives of the mitogen-activated protein kinases, as well as the casein kinase 1 (CK1) family of protein kinases are important mediators of adequate response to cellular stress following inflammatory and metabolic stressors, DNA damage, and others. In their physiologic roles, they are responsible for the regulation of cell cycle progression, cell proliferation and differentiation, and apoptosis. Dysregulation of the underlying pathways consequently has been identified in various cancer types, including pancreatic cancer. Pharmacological targeting of those pathways has been the field of interest for several years. While success in earlier studies was limited due to lacking specificity and off-target effects, more recent improvements in small molecule inhibitor design against stress-activated protein kinases and their use in combination therapies have shown promising in vitro results. Consequently, targeting of JNK, p38, and CK1 protein kinase family members may actually be of particular interest in the field of precision medicine in patients with highly deregulated kinase pathways related to these kinases. However, further studies are warranted, especially involving in vivo investigation and clinical trials, in order to advance inhibition of stress-activated kinases to the field of translational medicine.

Inhibition of Peripheral ERK Signaling Ameliorates Persistent Muscle Pain Around Trigger Points in Rats

The purpose of this study was to investigate whether the ERK signaling pathway was involved in ameliorating chronic myofascial hyperalgesia from contused gastrocnemius muscle in rats. We established an animal model associated with myofascial pain syndrome and described the mechanism of muscle pain in an animal model. Changes in the mechanical pain threshold were observed 0.5, 1, 2, 3, 4, 5, 8, 12, 18, and 24 h after ERK inhibitor injection around myofascial trigger points (MTrPs) of the gastrocnemius muscle in rats. Morphological changes in gastrocnemius muscle cells were observed by hematoxylin and eosin (H&E) staining. ERK signaling pathway activation was detected through immunohistochemistry and Western blotting. The main morphological characteristics of injured muscle fibers around MTrPs include gathered circular or elliptical shapes of different sizes in the cross-section and continuous inflated and tapering fibers in the longitudinal section. After intramuscular injection of U0126 (ERK inhibitor), the mechanical pain threshold significantly increased. The reduction in mechanical hyperalgesia was accompanied by reduced ERK protein phosphorylation, myosin light chain kinase (MLCK) protein, p-MLC protein expression, and the cross-sectional area of skeletal muscle cells around MTrPs. An ERK inhibitor contributed to the attenuation of mechanical hyperalgesia in the rat myofascial pain model, and the increase in pain threshold may be related to MLCK downregulation and other related contraction-associated proteins by ERK.

The impact of microRNAs on myeloid-derived suppressor cells in cancer

Inflammation promotes cancer development. To a large extent, this can be attributed to the recruitment of myeloid-derived suppressor cells (MDSCs) to tumors. These cells are known for establishing an immunosuppressive tumor microenvironment by suppressing T cell activities. However, MDSCs also promote metastasis and angiogenesis. Critically, as small non-coding RNAs that regulate gene expression, microRNAs (miRNAs) control MDSC activities. In this review, we discuss how miRNA networks regulate key MDSC signaling pathways, how they shape MDSC development, differentiation and activation, and how this impacts tumor development. By targeting the expression of miRNAs in MDSCs, we can alter their main signaling pathways. In turn, this can compromise their ability to promote multiple hallmarks of cancer. Therefore, this may represent a new powerful strategy for cancer immunotherapy.

Exosomal microRNAs in hepatocellular carcinoma

Hepatocellular carcinoma is one of the most common malignant tumors worldwide and the fourth leading cause of cancer-related deaths. The prognosis of hepatocellular carcinoma patients is extremely poor due to the occult onset and high metastasis of hepatocellular carcinoma. Therefore, biomarkers with high specificity and sensitivity are of great importance in early screening, diagnosis prognosis, and treatment of hepatocellular carcinoma patients. Exosomes are tiny vesicles secreted by various types of cells, which can serve as mediators of intercellular communication to regulate the tumor microenvironment, and play a key role in the occurrence, development, prognosis, monitor and treatment of hepatocellular carcinoma. As microRNA deliverer, exosomes are involved in multiple life activities by regulating target genes of recipient cells such as proliferation, invasion, metastasis and apoptosis of cancer cells. In this review, we summarized the composition, active mechanism and function of exosomal microRNAs in hepatocellular carcinoma, and elaborated on their potential application value of early diagnosis and treatment in hepatocellular carcinoma.

Dietary polyphenols suppress chronic inflammation by modulation of multiple inflammation-associated cell signaling pathways

The high failure rate of the reductionist approach to discover effective and safe drugs to treat chronic inflammatory diseases has led scientists to seek alternative ways. Recently, targeting cell signaling pathways has been utilized as an innovative approach to discover drug leads from natural products. Cell signaling mechanisms have been identified playing key role in diverse diseases by inducing proliferation, cell survival and apoptosis. Phytochemicals are known to be able to modulate the cellular and molecular networks which are associated to chronic diseases including cancer-associated inflammation. In this review, the roles of dietary polyphenols (apigenin, kaempferol, quercetin, curcumin, genistein, isoliquiritigenin, resveratrol and gallic acid) in modulating multiple inflammation-associated cell signaling networks are deliberated. Scientific databases on suppressive effects of the polyphenols on chronic inflammation via modulation of the pathways especially in the recent five years are gathered and critically analyzed. The polyphenols are able to modulate several inflammation-associated cell signaling pathways, namely nuclear factor-kappa β, mitogen activated protein kinases, Wnt/β-catenin and phosphatidylinositol 3-kinase and protein kinase B via selective actions on various components of the networks. The suppressive effects of the polyphenols on the multiple cell signaling pathways reveal their potential use in prevention and treatment of chronic inflammatory disorders. Understanding the mechanistic effects involved in modulation of the signaling pathways by the polyphenols is necessary for lead identification and development of future functional foods for prevention and treatment of chronic inflammatory diseases.

Mixed signals - how Trypanosoma cruzi exploits host-cell communication and signaling to establish infection

Chagas disease (American trypanosomiasis) is a 'neglected' pathology that affects millions of people worldwide, mainly in Latin America. Trypanosoma cruzi, the causative agent, is an obligate intracellular parasite with a complex and diverse biology that infects several mammalian species, including humans. Because of genetic variability among strains and the presence of four biochemically and morphologically distinct parasite forms, the outcome of T. cruzi infection varies considerably depending on host cell type and parasite strain. During the initial contact, cellular communication is established by host-recognition-mediated responses, followed by parasite adherence and penetration. For this purpose, T. cruzi expresses a variety of proteins that modify the host cell, enabling it to safely reach the cytoplasm. After entry into the host cell, T. cruzi forms a transitory structure termed 'parasitophorous vacuole' (PV), followed by its cytoplasmic replication and differentiation after PV rupture, and subsequent invasion of other cells. The success of infection, maintenance and survival inside host cells is facilitated by the ability of T. cruzi to subvert various host signaling mechanisms. We focus in this Review on the various mechanisms that induce host cytoskeletal rearrangements, activation of autophagy-related proteins and crosstalk among major immune response regulators, as well as recent studies on the JAK-STAT pathway.

An experimental strategy to probe Gq contribution to signal transduction in living cells

Heterotrimeric G protein subunits Gαq and Gα11 are inhibited by two cyclic depsipeptides, FR900359 (FR) and YM-254890 (YM), both of which are being used widely to implicate Gq/11 proteins in the regulation of diverse biological processes. An emerging major research question therefore is whether the cellular effects of both inhibitors are on-target, that is, mediated via specific inhibition of Gq/11 proteins, or off-target, that is, the result of nonspecific interactions with other proteins. Here we introduce a versatile experimental strategy to discriminate between these possibilities. We developed a Gαq variant with preserved catalytic activity, but refractory to FR/YM inhibition. A minimum of two amino acid changes were required and sufficient to achieve complete inhibitor resistance. We characterized the novel mutant in HEK293 cells depleted by CRISPR–Cas9 of endogenous Gαq and Gα11 to ensure precise control over the Gα-dependent cellular signaling route. Using a battery of cellular outcomes with known and concealed Gq contribution, we found that FR/YM specifically inhibited cellular signals after Gαq introduction via transient transfection. Conversely, both inhibitors were inert across all assays in cells expressing the drug-resistant variant. These findings eliminate the possibility that inhibition of non-Gq proteins contributes to the cellular effects of the two depsipeptides. We conclude that combined application of FR or YM along with the drug-resistant Gαq variant is a powerful in vitro strategy to discern on-target Gq against off-target non-Gq action. Consequently, it should be of high value for uncovering Gq input to complex biological processes with high accuracy and the requisite specificity.

Modulating NF-κB, MAPK, and PI3K/AKT signaling by ergothioneine attenuates iron overload-induced hepatocellular injury in rats

The liver is highly susceptible to iron overload-evoked oxidative injury. Ergothioneine is a thio-histidine amino acid that has exhibited strong antioxidant and metal chelating activities. This study aimed at exploring the potential modulating effects of ergothioneine on iron-triggered liver injury. The results showed that ergothioneine inhibited iron-evoked inflammation and apoptosis as demonstrated by a significant reduction in tumor necrosis factor-α and interleukin-6 levels and in caspase-3 activity. Ergothioneine significantly improved liver cell survival as indicated by modulating phosphatidylinositol 3-kinase/protein kinase B signaling. Consistent with reduced necrotic cell death, ergothioneine diminished the iron-evoked histopathological changes and decreased serum activity of the liver enzymes. Mechanistically, ergothioneine reduced nuclear translocation of nuclear factor kappa B p65 and modulated p38 mitogen-activated protein kinase/c-Fos signaling. In addition, it enhanced the liver tissue antioxidant potential and curbed hepatic iron load. Together, these results point out the modulatory effects of ergothioneine on iron-evoked liver cell injury that are possibly mediated via anti-inflammatory, antioxidant, and possible iron chelation capabilities.