Anti-inflammatory effects of nobiletin on TLR4/TRIF/IRF3 and TLR9/IRF7 signaling pathways in prostate cancer cells

Nobiletin enhances the antifungal activity of eugenol nanoemulsion against Penicillium italicum in both in vitro and in vivo settings

The study prepared and used eugenol nanoemulsion loaded with nobiletin as fungistat to study its antifungal activity and potential mechanism of Penicillium italicum (P. italicum). The results showed that the minimum inhibitory concentration (MIC) of eugenol nanoemulsion loaded with nobiletin (EGN) was lower than that of pure eugenol nanoemulsion (EG), which were 160 μg/mL and 320 μg/mL, respectively. At the same time, the mycelial growth inhibition rate of EGN nanoemulsion (54.68 %) was also higher than that of EG nanoemulsion (9.92 %). This indicates that EGN nanoemulsion is more effective than EG nanoemulsion. Compared with EG nanoemulsion, the treatment of EGN nanoemulsion caused more serious damage to the cell structure of P. italicum. At the same time, in vitro inoculation experiments found that EGN nanoemulsion has better control and delay the growth and reproduction of P. italicum in citrus fruits. And the results reflected that EGN nanoemulsion may be considered as potential resouces of natural antiseptic to inhibit blue mold disease of citrus fruits, because it has good antifungal activity.

Immune-inflammatory modulation by natural products derived from edible and medicinal herbs used in Chinese classical prescriptions

BACKGROUND

Edible and medicinal herbs1 (EMHs) refer to a class of substances with dual attribution of food and medicine. These substances are traditionally used as food and also listed in many international pharmacopoeias, including the European Pharmacopoeia, the United States Pharmacopoeia, and the Chinese Pharmacopoeia. Some classical formulas that are widely used in traditional Chinese medicine include a series of EMHs, which have been shown to be effective with obvious characteristics and advantages. Notably, these EMHs and Chinese classical prescriptions2 (CCPs) have also attracted attention in international herbal medicine research because of their low toxicity and high efficiency as well as the rich body of experience for their long-term clinical use.

PURPOSE

Our purpose is to explore the potential therapeutic effect of EMHs with immune-inflammatory modulation for the study of modern cancer drugs.

STUDY DESIGN

In the present study, we present a detailed account of some EMHs used in CCPs that have shown considerable research potential in studies exploring modern drugs with immune-inflammatory modulation.

METHODS

Approximately 500 publications in the past 30 years were collected from PubMed, Web of Science and ScienceDirect using the keywords, such as natural products, edible and medicinal herbs, Chinese medicine, classical prescription, immune-inflammatory, tumor microenvironment and some related synonyms. The active ingredients instead of herbal extracts or botanical mixtures were focused on and the research conducted over the past decade were discussed emphatically and analyzed comprehensively.

RESULTS

More than ten natural products derived from EMHs used in CCPs are discussed and their immune-inflammatory modulation activities, including enhancing antitumor immunity, regulating inflammatory signaling pathways, lowering the proportion of immunosuppressive cells, inhibiting the secretion of proinflammatory cytokines, immunosuppressive factors, and inflammatory mediators, are summarized.

CONCLUSION

Our findings demonstrate the immune-inflammatory modulating role of those EMHs used in CCPs and provide new ideas for cancer treatment in clinical settings.

Nobiletin regulates intracellular Ca2+ levels via IP3R and ameliorates neuroinflammation in Aβ42-induced astrocytes

Astrocytes are the major glial cells in the human brain and provide crucial metabolic and trophic support to neurons. The amyloid-β peptide (Aβ) alter the morphological and functional properties of astrocytes and induce inflammation and calcium dysregulation, contributing to Alzheimer's disease (AD) pathology. Recent studies highlight the role of Toll-like receptor (TLR) 4/nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling in inflammation. Reactive oxygen species (ROS) generated due to Aβ, induce apoptosis in the brain cells worsening AD progression. Astrocytic cell surface receptors, such as purinergic receptors (P2Y1 and P2Y2), metabotropic glutamate receptor (mGLUR)5, α7 nicotinic acetylcholine receptor (α7nAChR), and N-methyl-d-aspartate receptors (NMDARs), have been suggested to interact with inositol trisphosphate receptor (IP3R) on the endoplasmic reticulum (ER) to induce Ca2+ movement from ER to cytoplasm, causing Ca2+ dysregulation. We found that the citrus flavonoid nobiletin (NOB) protected primary astrocytes from Aβ42-induced cytotoxicity and inhibited TLR4/NF-κB signaling in Aβ42-induced primary rat astrocytes. NOB was found to regulate Aβ42-induced ROS levels through Keap1-Nrf2 pathway. The receptors P2Y1, P2Y2, mGLUR5, α7nAChR, and NMDARs induced intracellular Ca2+ levels by activating IP3R and NOB regulated them, thereby regulating intracellular Ca2+ levels. Molecular docking analysis revealed a possible interaction between NOB and IP3R in IP3R regulation. Furthermore, RNA sequencing revealed various NOB-mediated biological signaling pathways, such as the AD-presenilin, AD-amyloid secretase, and Wnt signaling pathway, suggesting possible neuroprotective roles of NOB. To conclude, NOB is a promising therapeutic agent for AD and works by modulating AD pathology at various levels in Aβ42-induced primary rat astrocytes.

Phytochemistry, pharmacological properties and pharmacokinetics of Citri Reticulatae Pericarpium: A systematic review

ETHNOPHARMACOLOGICAL RELEVANCE

Citri Reticulatae Pericarpium (CRP), known as Chen Pi in China, is the most commonly used medicine for regulating qi. As a traditional medicine, CRP has been extensively used in the clinical treatment of nausea, vomiting, cough and phlegm for thousands of years. It is mainly distributed in Guangdong, Sichuan, Fujian and Zhejiang in China. Due to its high frequency of use, many scholars have conducted a lot of research on it and the related chemical constituents it contains. In this review, the research progress on phytochemistry, pharmacology, pharmacokinetics and toxicology of CRP are summarized.

AIM OF THE REVIEW

The review aims to sort out the methods of extraction and purification, pharmacological activities and mechanisms of action, pharmacokinetics and toxicology of the chemical constituents in CRP, in order to elaborate the future research directions and challenges for the study of CRP and related chemical constituents.

MATERIALS AND METHODS

Valid and comprehensive relevant information was collected from China National Knowledge Infrastructure, Web of Science, PubMed and so on.

RESULTS

CRP contains a variety of compounds, of which terpenes, flavonoids and alkaloids are the main components, and they are also the primary bioactive components that play a pharmacological role. Flavonoids and terpenes are extracted and purified by aqueous and alcoholic extraction methods, assisted by ultrasonic and microwave extraction, in order to achieve higher yields with less resources. Pharmacological studies have shown that CRP possesses a variety of highly active chemical components and a wide range of pharmacological activities, including anti-tumor, anti-inflammatory, immunomodulatory, hepatoprotective, therapeutic for cardiovascular-related disorders, antioxidant, antibacterial, and neuroprotective effects.

CONCLUSIONS

There is a diversity in the chemical compositions of CRP, which have multiple biological activities and promising applications. However, the pharmacological activities of CRP are mainly dependent on the action of its chemical components, but the relationship between the structure of chemical components and the biological effects has not been thoroughly investigated, and therefore, the structure-activity relationship is an issue that needs to be elucidated urgently. In addition, the pharmacokinetic studies of the relevant components can be further deepened and the correlation studies between pharmacological effects and syndromes of TCM can be expanded to ensure the effectiveness and rationality of CRP for human use.

Comprehensive data mining reveals RTK/RAS signaling pathway as a promoter of prostate cancer lineage plasticity through transcription factors and CNV

Prostate cancer lineage plasticity is a key driver in the transition to neuroendocrine prostate cancer (NEPC), and the RTK/RAS signaling pathway is a well-established cancer pathway. Nevertheless, the comprehensive link between the RTK/RAS signaling pathway and lineage plasticity has received limited investigation. In particular, the intricate regulatory network governing the interplay between RTK/RAS and lineage plasticity remains largely unexplored. The multi-omics data were clustered with the coefficient of argument and neighbor joining algorithm. Subsequently, the clustered results were analyzed utilizing the GSEA, gene sets related to stemness, multi-lineage state datasets, and canonical cancer pathway gene sets. Finally, a comprehensive exploration of the data based on the ssGSEA, WGCNA, GSEA, VIPER, prostate cancer scRNA-seq data, and the GPSAdb database was conducted. Among the six modules in the clustering results, there are 300 overlapping genes, including 3 previously unreported prostate cancer genes that were validated to be upregulated in prostate cancer through RT-qPCR. Function Module 6 shows a positive correlation with prostate cancer cell stemness, multi-lineage states, and the RTK/RAS signaling pathway. Additionally, the 19 leading-edge genes of the RTK/RAS signaling pathway promote prostate cancer lineage plasticity through a complex network of transcriptional regulation and copy number variations. In the transcriptional regulation network, TP63 and FOXO1 act as suppressors of prostate cancer lineage plasticity, whereas RORC exerts a promoting effect. This study provides a comprehensive perspective on the role of the RTK/RAS pathway in prostate cancer lineage plasticity and offers new clues for the treatment of NEPC.

Recent advances in flavonoid compounds for the treatment of prostate cancer

Prostate cancer is a malignant epithelial tumor of the prostate gland and is the most common malignant tumor of the male genitourinary system. Pharmacological therapies, including chemotherapy and androgen deprivation therapy, play a key role in the treatment of prostate cancer. However, drug resistance and side effects limit the use of these drugs and so there is a need for new drug therapies for prostate cancer patients. Flavonoids, with their wide range of sources and diverse biological activities, have attracted much attention in the field of anti-tumor drug screening. In 2016, at least 58 flavonoids were reported to have anti-prostate cancer activity. In recent years, six additional flavonoid compounds have been found to have anti-prostate cancer potential. In this review, we have collected a large amount of evidence on the anti-prostate cancer effects of these six flavonoids, including a large number of cellular experiments and a small number of preclinical animal experiments. In addition, we predicted their drug-forming properties using Schrödinger's QikProp software and ADMETlab due to the lack of in vivo pharmacokinetic data for the six compounds. In conclusion, this review has fully confirmed the anti-prostate cancer effects of these six flavonoids, summarized their mechanisms of action and predicted their druggability. It provides a reference for the further development of these compounds into anti-prostate cancer drugs.

The Circadian Nobiletin-ROR Axis Suppresses Adipogenic Differentiation and IκBα/NF-κB Signaling in Adipocytes

Obesity is a known risk factor for metabolic diseases and is often associated with chronic inflammation in adipose tissue. We previously identified the polyethoxylated flavonoid Nobiletin (NOB) as a circadian clock modulator that directly binds to and activates the ROR receptors in the core oscillator, markedly improving metabolic fitness in obese mice. Here, we show that NOB enhanced the oscillation of core clock genes in differentiated 3T3-L1 adipocytes, including ROR target genes such as Bmal1, Cry1, Dec1, and Dec2. NOB inhibited lipid accumulation in 3T3-L1 and SVF cells, concomitant with the dysregulated circadian expression of adipogenic differentiation-related genes including Cebpb, Pparg, Lpl, Scd1, and Fas. Importantly, RORα/RORγ double knockdown in 3T3-L1 cells (Ror DKD) significantly attenuated the effects of NOB on circadian gene expression and lipid accumulation. Furthermore, whereas NOB upregulated the expression of IκBα, a target of RORs, to inhibit NF-κB activation and proinflammatory cytokine expression, Ror DKD cells exhibited a heightened activation of the NF-κB pathway, further indicating a requisite role of RORs for NOB efficacy in adipocytes. Together, these results highlight a significant regulatory function of the NOB-ROR axis in the circadian expression of clock and clock-controlled genes in adipocytes, thereby governing adipogenic differentiation, lipogenesis, and inflammation.

Citri Reticulatae Pericarpium Limits TLR-4-Triggered Inflammatory Response in Raw264.7 Macrophages by Activating RasGRP3

Inflammation is an important immune response to pathogen invasion, but excessive inflammation leads to tissue injury and even cytokine storm. Therefore, proper response is needed depending on the intensity of the infection. Ras guanine nucleotide releasing protein 3 (RasGRP3) is a regulator of the TLR-mediated response. In low-intensity inflammation, it negatively regulates production of pro-inflammatory cytokines, especially IL-6. Citri Reticulatae Pericarpium, the peel of Citrus reticulata Blanco, is a major medicinal herb in Korean medicine. The present study aims to investigate whether the Citri Reticulatae Pericarpium extract (CRE) has immunomodulatory activity using the Raw264.7 macrophage. Also, we investigated the effect of CRE on RasGRP3 expression. In the present study, CRE reduced IL-6 production in the low-LPS environment (1 ng/mL) and did not in the high-LPS environment (100 ng/mL). The suppression of IL-6 production in the low-LPS environment (1 ng/mL) was abolished after the pretreatment of RasGRP3 siRNA. The reduced RasGRP3 protein content by 100 ng/mL LPS treatment was increased by CRE treatment. Additionally, nobiletin, a major component of CRE showed a suppressive effect on IL-6 production in the low-LPS environment (1 ng/mL). The present results suggest that CRE alleviates inflammatory response via activating RasGRP3 expression in low-intensity inflammation.

Circadian disruption: from mouse models to molecular mechanisms and cancer therapeutic targets

The circadian clock is a timekeeping system for numerous biological rhythms that contribute to the regulation of numerous homeostatic processes in humans. Disruption of circadian rhythms influences physiology and behavior and is associated with adverse health outcomes, especially cancer. However, the underlying molecular mechanisms of circadian disruption-associated cancer initiation and development remain unclear. It is essential to construct good circadian disruption models to uncover and validate the detailed molecular clock framework of circadian disruption in cancer development and progression. Mouse models are the most widely used in circadian studies due to their relatively small size, fast reproduction cycle, easy genome manipulation, and economic practicality. Here, we reviewed the current mouse models of circadian disruption, including suprachiasmatic nuclei destruction, genetic engineering, light disruption, sleep deprivation, and other lifestyle factors in our understanding of the crosstalk between circadian rhythms and oncogenic signaling, as well as the molecular mechanisms of circadian disruption that promotes cancer growth. We focused on the discoveries made with the nocturnal mouse, diurnal human being, and cell culture and provided several circadian rhythm-based cancer therapeutic strategies.

Phytochemicals Derived from Agricultural Residues and Their Valuable Properties and Applications

Billions of tons of agro-industrial residues are produced worldwide. This is associated with the risk of pollution as well as management and economic problems. Simultaneously, non-edible portions of many crops are rich in bioactive compounds with valuable properties. For this reason, developing various methods for utilizing agro-industrial residues as a source of high-value by-products is very important. The main objective of the paper is a review of the newest studies on biologically active compounds included in non-edible parts of crops with the highest amount of waste generated annually in the world. The review also provides the newest data on the chemical and biological properties, as well as the potential application of phytochemicals from such waste. The review shows that, in 2020, there were above 6 billion tonnes of residues only from the most popular crops. The greatest amount is generated during sugar, oil, and flour production. All described residues contain valuable phytochemicals that exhibit antioxidant, antimicrobial and very often anti-cancer activity. Many studies show interesting applications, mainly in pharmaceuticals and food production, but also in agriculture and wastewater remediation, as well as metal and steel industries.

Modulation of type I interferon signaling by natural products in the treatment of immune-related diseases

Type I interferon (IFN) is considered as a bridge between innate and adaptive immunity. Proper activation or inhibition of type I IFN signaling is essential for host defense against pathogen invasion, tumor cell proliferation, and overactive immune responses. Due to intricate and diverse chemical structures, natural products and their derivatives have become an invaluable source inspiring innovative drug discovery. In addition, some natural products have been applied in clinical practice for infection, cancer, and autoimmunity over thousands of years and their promising curative effects and safety have been well-accepted. However, whether these natural products are primarily targeting type I IFN signaling and specific molecular targets involved are not fully elucidated. In the current review, we thoroughly summarize recent advances in the pharmacology researches of natural products for their type I IFN activity, including both agonism/activation and antagonism/inhibition, and their potential application as therapies. Furthermore, the source and chemical nature of natural products with type I IFN activity are highlighted and their specific molecular targets in the type I IFN pathway and mode of action are classified. In conclusion, natural products possessing type I IFN activity represent promising therapeutic strategies and have a bright prospect in the treatment of infection, cancer, and autoimmune diseases.

Polymethoxyflavones from citrus peel: advances in extraction methods, biological properties, and potential applications

Citrus peel, as an effective component of citrus by-products, contains a large number of natural active components, including pectin, vitamins, dietary fiber, essential oil, phenolic compounds, flavonoids, and so on. With the development of the circular economy, citrus peel has attracted extensive concern in the food industry. The exploitation of citrus peel would assist in excavating potential properties and alleviating the environmental burden. Polymethoxyflavones (PMFs) exist almost in citrus peel, which have remarkable biological activities including antioxidant, anti-inflammatory, anti-cancer, and anti-obesity. Therefore, PMFs from citrus peel have the potential to develop as dietary supplements in the near future. Collectively, it is essential to take action to optimize the extraction conditions of PMFs and make the most of the extracts. This review mainly compiles several extraction methods and bioactivities of PMFs from citrus peel and introduces different applications including food processing, pharmaceutical industry, and plant rhizosphere to develop better utilization of citrus PMFs.

The Crucial Role of AR-V7 in Enzalutamide-Resistance of Castration-Resistant Prostate Cancer

Simple Summary

Androgen receptor splice variant 7 (AR-V7) has always been considered a key driver for triggering enzalutamide resistance of castration-resistant prostate cancer (CRPC). In recent years, both the homeostasis of AR-V7 protein and AR-V7’s relationship with LncRNAs have gained great attention with in-depth studies. Starting from protein stability and LncRNA, the paper discusses and summarizes the mechanisms and drugs that affect the CRPC patients’ sensitivity to enzalutamide by regulating the protein or transcriptional stability of AR-V7, hoping to provide therapeutic ideas for subsequent research to break through the CRPC therapeutic bottleneck.

Abstract

Prostate cancer (PCa) has the second highest incidence of malignancies occurring in men worldwide. The first-line therapy of PCa is androgen deprivation therapy (ADT). Nonetheless, most patients progress to castration-resistant prostate cancer (CRPC) after being treated by ADT. As a second-generation androgen receptor (AR) antagonist, enzalutamide (ENZ) is the current mainstay of new endocrine therapies for CRPC in clinical use. However, almost all patients develop resistance during AR antagonist therapy due to various mechanisms. At present, ENZ resistance (ENZR) has become challenging in the clinical treatment of CRPC. AR splice variant 7 (AR-V7) refers to a ligand-independent and constitutively active variant of the AR and is considered a key driver of ENZR in CRPC. In this review, we summarize the mechanisms and biological behaviors of AR-V7 in ENZR of CRPC to contribute novel insights for CRPC therapy.

Regulated cell death (RCD) in cancer: key pathways and targeted therapies

Regulated cell death (RCD), also well-known as programmed cell death (PCD), refers to the form of cell death that can be regulated by a variety of biomacromolecules, which is distinctive from accidental cell death (ACD). Accumulating evidence has revealed that RCD subroutines are the key features of tumorigenesis, which may ultimately lead to the establishment of different potential therapeutic strategies. Hitherto, targeting the subroutines of RCD with pharmacological small-molecule compounds has been emerging as a promising therapeutic avenue, which has rapidly progressed in many types of human cancers. Thus, in this review, we focus on summarizing not only the key apoptotic and autophagy-dependent cell death signaling pathways, but the crucial pathways of other RCD subroutines, including necroptosis, pyroptosis, ferroptosis, parthanatos, entosis, NETosis and lysosome-dependent cell death (LCD) in cancer. Moreover, we further discuss the current situation of several small-molecule compounds targeting the different RCD subroutines to improve cancer treatment, such as single-target, dual or multiple-target small-molecule compounds, drug combinations, and some new emerging therapeutic strategies that would together shed new light on future directions to attack cancer cell vulnerabilities with small-molecule drugs targeting RCD for therapeutic purposes.

Downregulated TICAM1 is a prognostic biomarker and associated with immune tolerance of Wilms tumor patients

Background

TIR domain containing adaptor molecule 1 (TICAM1) is a coding gene participating in immune and inflammation responses to malignant cells. However, the role of TICAM1 in Wilms tumor (WT) is rarely known.

Materials and methods

The expression level of TICAM1 was calculated in the WT TARGET cohort and validated using the GSE66405 cohort. The Kaplan–Meier method was employed to investigate the potential clinical value of TICAM1 and the association between its expression level and clinical features. The influence of TICAM1 on immune infiltration was examined by ESTIMATE, CIBERSORT and MCPcounter algorithms. IC50 of chemotherapeutic drugs was calculated by “pRRophetic” R package.

Results

TICAM1 was downregulated in WT patients with worse prognosis and a more advanced clinical stage. Moreover, a low expression level of TICAM1 contributed to less immune cell infiltration, few protective immune cells and more antitumor immune cells.

Conclusions

TICAM1 exerts a significant impact on the prognosis, progression and immune infiltration condition of WT.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01326-5.

Nobiletin as an inducer of programmed cell death in cancer: a review

Cancer resistance to therapy is a big issue in cancer therapy. Tumours may develop some mechanisms to reduce the induction of cell death, thus stimulating tumour growth. Cancer cells may show a low expression and activity of tumour suppressor genes and a low response to anti-tumour immunity. These mutations can increase the resistance of cancer cells to programmed cell death mechanisms such as apoptosis, ferroptosis, pyroptosis, autophagic cell death, and some others. The upregulation of some mediators and transcription factors such as Akt, nuclear factor of κB, signal transducer and activator of transcription 3, Bcl-2, and others can inhibit cell death in cancer cells. Using adjuvants to induce the killing of cancer cells is an interesting strategy in cancer therapy. Nobiletin (NOB) is a herbal-derived agent with fascinating anti-cancer properties. It has been shown to induce the generation of endogenous ROS by cancer cells, leading to damage to critical macromolecules and finally cell death. NOB may induce the activity of p53 and pro-apoptosis mediators, and also inhibit the expression and nuclear translocation of anti-apoptosis mediators. In addition, NOB may induce cancer cell killing by modulating other mechanisms that are involved in programmed cell death mechanisms. This review aims to discuss the cellular and molecular mechanisms of the programmed cell death in cancer by NOB via modulating different types of cell death in cancer.

Nobiletin as a chemopreventive natural product against cancer, a comprehensive review

As a leading cause of death, second only to heart disease, cancer has always been one of the burning topics in medical research. When targeting multiple signal pathways in tumorigenesis chemoprevention, using natural or synthetic anti-cancer drugs is a vital strategy to reduce cancer damage. However, toxic effects, multidrug resistance (MDR) as well as cancer stem cells (CSCs) all prominently limited the clinical application of conventional anticancer drugs. With low side effects, strong biological activity, unique mechanism, and wide range of targets, natural products derived from plants are considered significant sources for new drug development. Nobiletin is one of the most attractive compounds, a unique flavonoid primarily isolated from the peel of citrus fruits. Numerous studies in vitro and in vivo have suggested that nobiletin and its derivatives possess the eminent potential to become effective cancer chemoprevention agents through various cellular and molecular levels. This article aims to comprehensively review the anticancer efficacy and specific mechanisms of nobiletin, enhancing our understanding of its chemoprevention properties and providing the latest research findings. At the end of this review, we also give some discussion and future perspectives regarding the challenges and opportunities in nobiletin efficient exploitation.

TLR13 contributes to skeletal muscle atrophy by increasing insulin resistance in chronic kidney disease

Objectives

Insulin resistance in chronic kidney disease (CKD) stimulates muscle wasting, but the molecular processes behind the resistance are undetermined. However, inflammation in skeletal muscle is implicated in the pathogenesis of insulin resistance and cachexia. Toll‐like receptors (TLRs) are known to regulate local innate immune responses, and microarray data have shown that Tlr13 is upregulated in the muscles of mice with CKD, but the relevance is unknown.

Materials and Methods

We performed in vitro experiments in C2C12 myotubes and constructed a CKD murine model using subtotal nephrectomy to conduct experiments in vivo.

Results

Tlr13 expression was stimulated in C2C12 myotubes treated with uremic serum. The expression of Tlr13 was also upregulated in the tibialis anterior muscles of mice with CKD. Tlr13 knockdown with siRNAs in skeletal muscle cells decreased insulin resistance despite the inclusion of uremic serum. This led to increased levels of p‐AKT and suppression of protein degradation. Using immunofluorescence staining and coimmunoprecipitation assay, we found that TLR13 recruits IRF3, which activates Irf3 expression, resulting in decreased AKT activity. Moreover, insulin resistance and proteolysis are re‐induced by Irf3 overexpression under Tlr13 deletion.

Conclusions

Our results indicate that TLR13 is involved in CKD‐mediated insulin resistance in muscle. In catabolic conditions where insulin signaling is impaired, targeting TLR13 may improve insulin sensitivity and prevent muscle atrophy.

The relationship between the efficacy of talazoparib and the functional toll-like receptors 3 and 9 in triple negative breast cancer

Poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) induce cell death by inhibiting the repair of DNA strand breaks binding to PARP and regulate immune cells functions. Toll-like receptors (TLRs) mediate the tumor microenvironment through the modulation of proinflammatory cytokines and chemokines. In this context, this study addressed the relationship between the efficacy of talazoparib (TAL) as a PARPi and the activation of TLR3 or TLR9 by Polyinosinic:polycytidylic acid (Poly I:C) or CpG oligodeoxynucleotides (CpG-ODN) stimulation, respectively in triple negative breast cancer (TNBC). TAL alone and the combination of TAL with Poly I:C or CpG-ODN induced cell death were analyzed by water-soluble tetrazolium salt 1 (WST-1), Annexin V analysis, acridine orange staining and mRNA levels of caspase-3 and caspase-8 in HCC1937 and HCC1937-R (TAL resistant) TNBC cells. Additionally, the expression of TLR3, TLR9 and interferon regulatory factor 7 (IRF7) was observed with immunofluorescence staining and western blot analysis. Our findings showed that TAL induced TLR3 and TLR9 activation and acted in synergy with TLR3 and TLR9 agonists in TNBC cells. The stimulation of TLR3 or TLR9 and TAL treatment caused significantly more apoptosis in TNBC cells through the over-expression of caspase-3 and caspase-8. Additionally, TAL combined with Poly I:C or CpG-ODN more increased TLR3, TLR9 and IRF7 protein levels in HCC1937 cells and treatment with TAL and Poly I:C had greater potential for overcoming TAL resistance. In conclusion, the combination of PARPi with TLR agonists may be a new therapeutic combined strategy for the effective immunotherapy of TNBC.

Overexpression of TRIM3 protects against LPS-induced acute kidney injury via repressing IRF3 pathway and NLRP3 inflammasome

PURPOSE

The pathological process of sepsis involves multiple system organs, including kidney. Sepsis-induced acute kidney injury (AKI) has high morbidity and high mortality. Overproduced inflammatory factors contribute to the occurrence and evolvement of AKI. Here, the role and underlying mechanism of tripartite motif containing 3 (TRIM3) and in AKI was explored.

METHODS

Lipopolysaccharide (LPS) was used for constructing AKI model both in vitro and in vivo. RT-PCR and western blot were performed to detect TRIM3, Interferon regulatory factor 3 (IRF3) and NLRP3-ASC-Caspase1 inflammasome. Upon selectively regulating the TRIM3 or IRF3 expression, the proliferation, apoptosis and inflammatory response were detected. The interaction between TRIM3 and IRF3 was verified by Immunoprecipitation (IP).

RESULTS

TRIM3 was down-regulated in mediated injury renal tubular epithelial cell line HK-2 treated with LPS. Overexpression of TRIM3 promoted cell viability and reduced apoptosis. In addition, overexpression of TRIM3 inhibited the expression of inflammatory factors (IL-1β, IL-6, TNF-α and IL-18), dampened the phosphorylation of IRF3 and repressed NLRP3 inflammasome activation. Furthermore, TRIM3 overexpression significantly eased the LPS-induced damage on AKI rat model and decreased the serum creatinine and urea nitrogen levels in rat kidney tissues. The results of immunohistochemistry (IHC) and Western blot manifested that TRIM3 was increased dramatically after TRIM3 was overexpressed in the rat kidney tissues, while IRF3 and NLRP3-ASC-Caspase1 inflammasome were significantly repressed following TRIM3 upregulation in the kidney tissues. Mechanistically, TRIM3 interacted with IRF3 and inhibited its phosphorylation.

CONCLUSION

Overexpression of TRIM3 protected against LPS-induced AKI by inhibiting the IRF3 pathway and NLRP3 inflammasome activation.

Selective degradation of AR-V7 to overcome castration resistance of prostate cancer

Androgen receptor splice variant 7 (AR-V7), a form of ligand-independent and constitutively activating variant of androgen receptor (AR), is considered as the key driver to initiate castration-resistant prostate cancer (CRPC). Because AR-V7 lacks ligand-binding domain, the AR-targeted therapies that aim to inactivate AR signaling through disrupting the interaction between AR and androgen are limited in CRPC. Thus, the emergence of AR-V7 has become the greatest challenge for treating CRPC. Targeting protein degradation is a recently proposed novel avenue for cancer treatment. Our previous studies have been shown that the oncoprotein AR-V7 is a substrate of the proteasome. Identifying novel drugs that can trigger the degradation of AR-V7 is therefore critical to cure CRPC. Here we show that nobiletin, a polymethoxylated flavonoid derived from the peel of Citrus fruits, exerts a potent anticancer activity via inducing G0/G1 phase arrest and enhancing the sensitivity of cells to enzalutamide in AR-V7 positive PC cells. Mechanically, we unravel that nobiletin selectively induces proteasomal degradation of AR-V7 (but not AR). This effect relies on its selective inhibition of the interactions between AR-V7 and two deubiquitinases USP14 and USP22. These findings not only enrich our understanding on the mechanism of AR-V7 degradation, but also provide an efficient and druggable target for overcoming CRPC through interfering the stability of AR-V7 mediated by the interaction between AR-V7 and deubiquitinase.

Nobiletin Decreases Inflammatory Mediator Expression in Tumor Necrosis Factor-Stimulated Human Periodontal Ligament Cells

Nobiletin, a biologically active substance in the skin of citrus fruits, has been reported to be an effective anti-inflammatory, anticancer, and antimicrobial agent. In this study, we aimed to examine the anti-inflammatory effects of nobiletin on tumor necrosis factor- (TNF-) stimulated human periodontal ligament cells (HPDLCs). Our results demonstrated that nobiletin treatment could decrease the expressions of inflammatory cytokines (C-X-C motif chemokine ligand (CXCL)10, C-C motif chemokine ligand (CCL)2, and interleukin- (IL-) 8), matrix metalloproteinases (MMPs) (MMP1 and MMP3), and prostaglandin-endoperoxide synthase 2 (PTGS2) in TNF-stimulated HPDLCs. Moreover, we revealed that nobiletin could inhibit the activation of nuclear factor- (NF-) κB and protein kinase B (AKT1) pathways in TNF-stimulated HPDLCs. Furthermore, nobiletin treatment enhanced nuclear factor, erythroid 2 like 2 (NFE2L2) and heme oxygenase 1 (HMOX1) expressions in TNF-stimulated HPDLCs. In conclusion, these findings suggest that nobiletin can inhibit inflammatory responses in TNF-stimulated HPDLCs by inhibiting NF-κB and AKT1 activations and upregulating the NFE2L2 and HMOX1 expression.

Flavonoids against the SARS-CoV-2 induced inflammatory storm

The disease severity of COVID-19, especially in the elderly and patients with co-morbidities, is characterized by hypercytokinemia, an exaggerated immune response associated with an uncontrolled and excessive release of proinflammatory cytokine mediators (cytokine storm). Flavonoids, important secondary metabolites of plants, have long been studied as therapeutic interventions in inflammatory diseases due to their cytokine-modulatory effects. In this review, we discuss the potential role of flavonoids in the modulation of signaling pathways that are crucial for COVID-19 disease, particularly those related to inflammation and immunity. The immunomodulatory ability of flavonoids, carried out by the regulation of inflammatory mediators, the inhibition of endothelial activation, NLRP3 inflammasome, toll-like receptors (TLRs) or bromodomain containing protein 4 (BRD4), and the activation of the nuclear factor erythroid-derived 2-related factor 2 (Nrf2), might be beneficial in regulating the cytokine storm during SARS-CoV-2 infection. Moreover, the ability of flavonoids to inhibit dipeptidyl peptidase 4 (DPP4), neutralize 3-chymotrypsin-like protease (3CL^pro) or to affect gut microbiota to maintain immune response, and the dual action of angiotensin-converting enzyme 2 (ACE-2) may potentially also be applied to the exaggerated inflammatory responses induced by SARS-CoV-2. Based on the previously proven effects of flavonoids in other diseases or on the basis of newly published studies associated with COVID-19 (bioinformatics, molecular docking), it is reasonable to assume positive effects of flavonoids on inflammatory changes associated with COVID-19. This review highlights the current state of knowledge of the utility of flavonoids in the management of COVID-19 and also points to the multiple biological effects of flavonoids on signaling pathways associated with the inflammation processes that are deregulated in the pathology induced by SARS-CoV-2. The identification of agents, including naturally occurring substances such as flavonoids, represents great approach potentially utilizable in the management of COVID-19. Although not clinically investigated yet, the applicability of flavonoids against COVID-19 could be a promising strategy due to a broad spectrum of their biological activities.

MicroRNAs and Natural Compounds Mediated Regulation of TGF Signaling in Prostate Cancer

Prostate cancer (PCa) is with rising incidence in male population globally. It is a complex anomaly orchestrated by a plethora of cellular processes. Transforming growth factor-beta (TGF-β) signaling is one of the key signaling pathways involved in the tumorigenesis of PCa. TGF-β signaling has a dual role in the PCa, making it difficult to find a suitable therapeutic option. MicroRNAs (miRNAs) mediated regulation of TGF-β signaling is responsible for the TGF-ß paradox. These are small molecules that modulate the expression of target genes and regulate cancer progression. Thus, miRNAs interaction with different signaling cascades is of great attention for devising new diagnostic and therapeutic options for PCa. Natural compounds have been extensively studied due to their high efficacy and low cytotoxicity. Here, we discuss the involvement of TGF-ß signaling in PCa with the interplay between miRNAs and TGF-β signaling and also review the role of natural compounds for the development of new therapeutics for PCa.

Evaluation of the Effects of Nobiletin on Toll-Like Receptor 3 Signaling Pathways in Prostate Cancer In Vitro

Nobiletin as a nontoxic dietary citrus flavonoid has anticancer effects in cancer. Toll-like receptor three has a role in prostate cancer progression. However the relationship among NOB and TLR3 signaling in PCa has not been elucidated, yet. Therefore, we aimed to evaluate the effects of NOB on the activation of TLR3 signaling pathways in PCa In Vitro. PC-3, LNCaP and HUVEC cells were used for comparison of NOB-mediated TLR3 signaling pathways. After treatment with NOB and Poly I:C alone and NOB + Poly I:C, RT-PCR, western blotting and ELISA assay were performed to evaluate changes in gene and protein expression level, as well as CASP8. NOB potentially induced TLR3/IRF3 signaling pathway and the activation of TLR3/IRF3 signaling pathway by both NOB and Poly I:C was more profound in LNCaP than PC-3 cells. However, the level of TRIF protein and CASP8 decreased after both NOB and Poly I:C incubation. NOB could mediate TLR3 signaling pathways. NOB + Poly I:C could improve the activation of TLR3/IRF3 signaling pathway. However, the activation of TRIF/RIPK1/FADD signaling pathway reduced. Therefore, the elucidation of molecular mechanisms of TLR3 signaling pathways and the combination effects of NOB + Poly I:C on apoptotic cell death are further studied.

Nobiletin in Cancer Therapy: How This Plant Derived-Natural Compound Targets Various Oncogene and Onco-Suppressor Pathways

Cancer therapy is a growing field, and annually, a high number of research is performed to develop novel antitumor drugs. Attempts to find new antitumor drugs continue, since cancer cells are able to acquire resistance to conventional drugs. Natural chemicals can be considered as promising candidates in the field of cancer therapy due to their multiple-targeting capability. The nobiletin (NOB) is a ubiquitous flavone isolated from Citrus fruits. The NOB has a variety of pharmacological activities, such as antidiabetes, antioxidant, anti-inflammatory, hepatoprotective, and neuroprotective. Among them, the antitumor activity of NOB has been under attention over recent years. In this review, we comprehensively describe the efficacy of NOB in cancer therapy. NOB induces apoptosis and cell cycle arrest in cancer cells. It can suppress migration and invasion of cancer cells via the inhibition of epithelial-to-mesenchymal transition (EMT) and EMT-related factors such as TGF-β, ZEB, Slug, and Snail. Besides, NOB inhibits oncogene factors such as STAT3, NF-κB, Akt, PI3K, Wnt, and so on. Noteworthy, onco-suppressor factors such as microRNA-7 and -200b undergo upregulation by NOB in cancer therapy. These onco-suppressor and oncogene pathways and mechanisms are discussed in this review.