Protective effects of Sparstolonin B, a selective TLR2 and TLR4 antagonist, on mouse endotoxin shock

Targeting chemokine-receptor mediated molecular signaling by ethnopharmacological approaches

ETHNOPHARMACOLOGICAL RELEVANCE

Infection and inflammation are critical to global human health status and the goal of current pharmacological interventions intends formulating medications/preventives as a measure to deal with this situation. Chemokines and their cognate receptors are major regulatory molecules in many of these ailments. Natural products have been a keen source to the drug development industry, every year contributing significantly to the growing list of FDA approved drugs. A multiverse of natural resource is employed as a part of curative regimen in folk/traditional/ethnomedicine which can be employed to discover, repurpose, and design potent medications for the diseases of clinical concern.

AIM OF THE STUDY

This review aims to systematically document the ethnopharmacologically active agents targeting the infectious-inflammatory diseases through the chemokine-receptor nexus.

MATERIALS AND METHODS

Articles related to chemokine/receptor modulating ethnopharmacological anti-inflammatory, anti-infectious natural sources, bioactive compounds, and formulations have been examined with special emphasis on women related diseases. The available literature has been thoroughly scrutinized for the application of traditional medicines in chemokine associated experimental methods, their regulatory outcomes, and pertinence to women's health wherever applicable. Moreover, the potential traditional regimens under clinical trials have been critically assessed.

RESULTS

A systematic and comprehensive review on the chemokine-receptor targeting ethnopharmaceutics from the available literature has been provided. The article discusses the implication of traditional medicine in the chemokine system dynamics in diverse infectious-inflammatory disorders such as cardiovascular diseases, allergic diseases, inflammatory diseases, neuroinflammation, and cancer. On this note, critical evaluation of the available data surfaced multiple diseases prevalent in women such as osteoporosis, rheumatoid arthritis, breast cancer, cervical cancer and urinary tract infection. Currently there is no available literature highlighting chemokine-receptor targeting using traditional medicinal approach from women's health perspective. Moreover, despite being potent in vitro and in vivo setups there remains a gap in clinical translation of these formulations, which needs to be strategically and scientifically addressed to pave the way for their successful industrial translation.

CONCLUSIONS

The review provides an optimistic global perspective towards the applicability of ethnopharmacology in chemokine-receptor regulated infectious and inflammatory diseases with special emphasis on ailments prevalent in women, consecutively addressing their current status of clinical translation and future directions.

The Toll-like Receptor-2/4 Antagonist, Sparstolonin B, and Inflammatory Diseases: A Literature Mining and Network Analysis

BACKGROUND

Sparstolonin B (SsnB) is characterized as a new toll-like receptor (TLR)-2/4 antagonist. However, the effects of SsnB on different inflammatory diseases have not been systemically reviewed.

METHODS

We investigated the effects of SsnB on inflammatory diseases with data mining and network analysis of literature, including frequency description, cluster analysis, association rule mining, functional enrichment, and protein-protein interaction (PPI) mining.

RESULTS

A total of 27 experimental reports were included. The ARRIVE 2.0 guidelines were used to evaluate the quality of animal studies. Frequency analysis revealed 13 different diseases (cardio-cerebrovascular system diseases account for 23.53%), 12 pharmacological effects (anti-inflammatory effect accounts for 53.85%), and 67 therapeutic targets. The overview of investigation sequence of SsnB studies was depicted by Sankey diagram. Cluster analysis classified the therapeutic targets for SsnB into four main categories: (1) NF-κB; (2) IL-1β, IL-6, and TNF-α; (3) TLR2, TLR4, and MyD88; (4) the other targets. Moreover, the Apriori association discovered two main association pairs: (1) TNF-α, IL-1β, and IL-6 and (2) TLR2, TLR4, and MyD88 (support range 33.33-50%, confidence range 83.33-88.89%). Functional enrichment of the therapeutic targets for SsnB showed that the top enriched items in the biological process were mainly the response to lipopolysaccharide (LPS)/bacterial origin and regulation of cytokine production. Finally, the PPI network and hub gene selection by maximal clique centrality (MCC) algorithm indicated the top ranked proteins were TNF-α, IL-1β, IL-6, AKT1, PPAR-γ, TLR4, CCL2, and TLR2.

CONCLUSION

These results emphasized the importance of TLR2/TLR4-MyD88-NF-κB-IL-1β/IL-6/TNF-α pathways as therapeutic targets of SsnB in inflammatory diseases.

The application of mirabilite in traditional Chinese medicine and its chemical constituents, processing methods, pharmacology, toxicology and clinical research

Purpose: This study reviews the use of mirabilite in traditional Chinese medicine and various preparations by describing its chemical composition, processing methods, pharmacology, toxicology, and clinical research progress. Methods: The applications and processing methods of mirabilite are searched in traditional and modern Chinese medical writings, and the articles on chemical composition, pharmacological effects, toxicology, and clinical studies of mirabilite and its combinations in PubMed and China Knowledge Network are reviewed, sorted, and analyzed. Results: The main chemical component of mirabilite is sodium sulfate decahydrate (Na2SO4·10H2O), followed by small amounts of sodium chloride, magnesium sulfate, calcium sulfate, and other inorganic salts. This study systematically organizes the history of the medicinal use of mirabilite in China for more than 2,000 years. This mineral has been used by nine Chinese ethnic groups (Han, Dai, Kazakh, Manchu, Mongolian, Tujia, Wei, Yi, and Tibetan) in a large number of prescription preparations. The Pharmacopoeia of the People's Republic of China (2020 edition) records stated that mirabilite can be used for abdominal distension, abdominal pain, constipation, intestinal carbuncle, external treatment of breast carbuncle, hemorrhoids, and other diseases. The traditional processing methods of mirabilite in China include refining, boiling, sautéing, filtration after hot water blistering, and firing. Since the Ming Dynasty, processing by radish has become the mainstream prepared method of mirabilite. Mirabilite can exhibit anti-inflammatory detumescence effects by inhibiting AMS, LPS, IL-6, IL-10, TNF-α, and NO levels and attenuating the upregulation of TNF-α and NF-κB genes. It can promote cell proliferation and wound healing by increasing the production of cytokines TGFβ1 and VEGF-A and gastrointestinal motility by increasing the release of vasoactive intestinal peptide, substance P, and motilin. It can increase the expression of low-density lipoprotein receptor and AKT phosphorylation in the liver by up-regulating bile acid synthesis genes; reduce TRB3 expression in the liver, FGF15 co-receptor KLB expression, and FGF15 production in the ileum, and JNK signal transduction; and increase the transcription of CYP7A1 to achieve a cholesterol-lowering effect. Mirabilite also has a variety of pharmacological effects, such as regulating intestinal flora, anti-muscle paralysis, anti-colon cancer, promoting water discharge, and analgesic. Only a few toxicological studies on mirabilite are available. External application of mirabilite can cause local skin to be flushed or itchy, and its oral administration is toxic to neuromuscular cells. The sulfur ions of its metabolites can also be toxic to the human body. At present, no pharmacokinetic study has been conducted on mirabilite as a single drug. This mineral has been widely used in the clinical treatment of inflammation, edema, wound healing, digestive system diseases, infusion extravasation, hemorrhoids, skin diseases, breast accumulation, muscle paralysis, intestinal preparation before microscopic examination, and other diseases and symptoms. Conclusion: Mirabilite has good application prospects in traditional Chinese medicine and ethnomedicine. In-depth research on its processing methods, active ingredients, quality control, pharmacokinetics, pharmacological and toxicological mechanisms, and standardized clinical application is needed. This paper provides a reference for the application and research of mirabilite in the future.

Transition-metal catalyzed C-H activation as a means of synthesizing complex natural products

Over the past few decades, the advent of C-H activation has led to a rethink among chemists about the synthetic strategies employed for multi-step transformations. Indeed, deploying innovative and masterful tricks against the numerous classical organic transformations has been the need of the hour. Despite this, the immense importance of C-H activation remains unfulfilled unless the methodology can be deployed for large-scale industrial processes and towards the concise, step-economic synthesis of prodigious natural products and pharmaceutical drugs. Lately, the growing potential of C-H activation methodology has indeed driven the pioneers of synthetic organic chemists into finding more efficient methods to accelerate the synthesis of such complex molecular scaffolds. This review aims to draw a general overview of the various C-H activation procedures that have been adopted for synthesizing these vast majority of structurally complicated natural products. Our objective lies in drawing a complete picture and taking the readers through the synthesis of a series of such complex organic compounds by simplified techniques, making it step-economic on a larger scale and thus instigating the readers to trigger the use of such methodology and uncover new, unique patterns for future synthesis of such natural products.

Phytocannabinoids Reduce Inflammation of Primed Macrophages and Enteric Glial Cells: An In Vitro Study

Intestinal inflammation is mediated by a subset of cells populating the intestine, such as enteric glial cells (EGC) and macrophages. Different studies indicate that phytocannabinoids could play a possible role in the treatment of inflammatory bowel disease (IBD) by relieving the symptoms involved in the disease. Phytocannabinoids act through the endocannabinoid system, which is distributed throughout the mammalian body in the cells of the immune system and in the intestinal cells. Our in vitro study analyzed the putative anti-inflammatory effect of nine selected pure cannabinoids in J774A1 macrophage cells and EGCs triggered to undergo inflammation with lipopolysaccharide (LPS). The anti-inflammatory effect of several phytocannabinoids was measured by their ability to reduce TNFα transcription and translation in J774A1 macrophages and to diminish S100B and GFAP secretion and transcription in EGCs. Our results demonstrate that THC at the lower concentrations tested exerted the most effective anti-inflammatory effect in both J774A1 macrophages and EGCs compared to the other phytocannabinoids tested herein. We then performed RNA-seq analysis of EGCs exposed to LPS in the presence or absence of THC or THC-COOH. Transcriptomic analysis of these EGCs revealed 23 differentially expressed genes (DEG) compared to the treatment with only LPS. Pretreatment with THC resulted in 26 DEG, and pretreatment with THC-COOH resulted in 25 DEG. To evaluate which biological pathways were affected by the different phytocannabinoid treatments, we used the Ingenuity platform. We show that THC treatment affects the mTOR and RAR signaling pathway, while THC-COOH mainly affects the IL6 signaling pathway.

BacSp222 bacteriocin as a novel ligand for TLR2/TLR6 heterodimer

OBJECTIVE AND DESIGN

BacSp222 bacteriocin is a bactericidal and proinflammatory peptide stimulating immune cells to produce selected cytokines and NO in NF-ĸB dependent manner. This study aims to identify the receptor which mediates this activity.

METHODS

We applied fluorescently labeled BacSp222 and a confocal microscopy imaging to analyze the direct interaction of the bacteriocin with the cells. Reporter HEK-Blue cells overexpressing human toll-like receptors (TLR2, TLR4, TLR5 or TLR2/TLR1 and TLR2/TLR6 heterodimers) were stimulated with BacSp222, and then the activity of NF-ĸB-dependent secreted embryonic alkaline phosphatase (SEAP) was measured. In turn, formylated peptide receptor (FPR) or TLR2 antagonists were used to verify bacteriocin-stimulated TNF production by murine monocyte-macrophage cell lines.

RESULTS

BacSp222 undergoes internalization into cells without disturbing the cell membrane. FPR antagonists do not affect TNF produced by BacSp222-stimulated murine macrophage-like cells. In contrast, BacSp222 stimulates NF-ĸB activation in HEK-Blue overexpressing TLR2 or TLR2/TLR6 heterodimer, but not TLR2/TLR1, TLR4 or TLR5 receptors. Moreover, TLR2-specific antagonists inhibit NF-ĸB signaling in BacSp222-stimulated HEK-Blue TLR2/TLR6 cells and reduce TNF release by BacSp222-treated RAW 264.7 and P388.D1.

CONCLUSIONS

BacSp222 is a novel ligand for TLR2/TLR6 heterodimer. By binding TLR complex the bacteriocin undergoes internalization, inducing proinflammatory signaling that employs MyD88 and NF-ĸB pathways.

Hyaluronan Regulates Neuronal and Immune Function in the Rat Small Intestine and Colonic Microbiota after Ischemic/Reperfusion Injury

BACKGROUND

Intestinal ischemia and reperfusion (IRI) injury induces acute and long-lasting damage to the neuromuscular compartment and dysmotility. This study aims to evaluate the pathogenetic role of hyaluronan (HA), a glycosaminoglycan component of the extracellular matrix, as a modulator of the enteric neuronal and immune function and of the colonic microbiota during in vivo IRI in the rat small intestine.

METHODS

mesenteric ischemia was induced in anesthetized adult male rats for 60 min, followed by 24 h reperfusion. Injured, sham-operated and non-injured animals were treated with the HA synthesis inhibitor, 4-methylumbelliferone (4-MU 25 mg/kg). Fecal microbiota composition was evaluated by Next Generation Sequencing. Neutrophil infiltration, HA homeostasis and toll like receptor (TLR2 and TLR4) expression in the small intestine were evaluated by immunohistochemical and biomolecular approaches (qRT-PCR and Western blotting). Neuromuscular responses were studied in vitro, in the absence and presence of the selective TLR2/4 inhibitor, Sparstolonin B (SsnB 10, 30 µM).

RESULTS

4-MU significantly reduced IRI-induced enhancement of potentially harmful Escherichia and Enterococcus bacteria. After IRI, HA levels, neutrophil infiltration, and TLR2 and TLR4 expression were significantly enhanced in the muscularis propria, and were significantly reduced to baseline levels by 4-MU. In the injured, but not in the non-injured and sham-operated groups, SsnB reduced both electrical field-stimulated (EFS, 0.1-40 Hz) contractions and EFS-induced (10 Hz) non-cholinergic non-adrenergic relaxations.

CONCLUSIONS

enhanced HA levels after intestinal IRI favors harmful bacteria overgrowth, increases neutrophil infiltration and promotes the upregulation of bacterial target receptors, TLR2 and TLR4, in the muscularis propria, inducing a pro-inflammatory state. TLR2 and TLR4 activation may, however, underlay a provisional benefit on excitatory and inhibitory neuronal pathways underlying peristalsis.

Anti-Inflammatory Effect of Sparstolonin B through Inhibiting Expression of NF-κB and STAT-1

Sparstolonin B (SsnB), which is found in Sparganium stoloniferum, prevents the synthesis of inflammatory mediators and is related to functional pathways of survival. In this study, we assessed the possible protective functions of SsnB on lipopolysaccharide (LPS)-induced inflammatory responses. We determined the functions of SsnB on controlling heme oxygenase (HO)-1, cyclooxygenase (COX-)2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). Furthermore, the distinct function of SsnB on the expression of iNOS and well-known pro-inflammatory mediators, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, were assessed in the pulmonary histological status of LPS-injected mice. SsnB upregulated the HO-1 production, inhibited luciferase-NF-κB interaction, and lowered COX-2/PGE2 and iNOS/NO, which lead to the reduction of STAT-1 phosphorylation. Moreover, SsnB enhanced the nuclear translocation of Nrf2, elevated the binding activity between Nrf2 and antioxidant response elements (AREs), and weakened IL-1β expression on LPS-treated HUVECs. SsnB-suppressed iNOS/NO synthesis was restored by the process of the RNAi inhibition of HO-1. In experiment with an LPS-injected animal model, SsnB remarkably decreased the iNOS expression in the pulmonary biostructure and TNF-α level in the bronchoalveolar lavage fluid (BALF). Therefore, these results demonstrate that SsnB is responsible for inflammation ameliorative activity by controlling iNOS through inhibition of both NF-κB expression and p-STAT-1. Therefore, SsnB could be a candidate for promoting novel clinical substances to remedy pathologic inflammation.

Inhibition of factor Xa activity, platelet aggregation, and experimentally induced thrombosis by Sparstolonin B

BACKGROUND

Sparstolonin B (SsnB) is an isocumarin compound extracted from medicinal plants such as Sparganium stoloniferum and Scirpus yagara with well documented anti-inflammatory activity. Here we examined if SsnB also possesses antithrombotic activity and the underlying mechanisms.

METHODS

Anti-thrombotic effects of SsnB were determined by measuring in vitro/ex vivo/in vivo clotting times, platelet aggregation assay, production and activity of factor Xa, nitric oxide, and expressions of relative proteins.

RESULTS

Treatment with SsnB prolonged the clotting time of human platelet-poor serum at concentrations comparable to the clinical anticoagulant rivaroxaban (as a positive control) and inhibited human platelet aggregation induced by adenosine diphosphate (ADP) or the thromboxane A2 analog U46619. SsnB also inhibited U46619-induced and ADP-induced phosphorylation of phospholipase C (PLC)γ2/protein kinase C (PKC) and intracellular calcium mobilization, both of which are required for platelet aggregation. In addition, SsnB inhibited expression of the cell adhesion factors P-selectin and PAC-1. SsnB increased production of the vasodilator nitric oxide and suppressed secretion of the vasoconstrictor endothelin-1 from ADP- or U46619-treated human umbilical vein endothelial cells. Further, SsnB reduced coagulation factor Xa (FXa) catalytic activity and production by endothelial cells as well as FXa-induced platelet aggregation.

CONCLUSION

Finally, SsnB injection reduced thrombus formation time, number, size, and related mortality in mouse models of thromboembolism. SsnB is a promising antithrombotic agent targeting both FXa and platelet aggregation pathways, which can overcome the side effects of existing antithrombotic agents.

Sparstolonin B suppresses free fatty acid palmitate-induced chondrocyte inflammation and mitigates post-traumatic arthritis in obese mice

Abnormal lipid metabolism, such as systemic increased free fatty acid, results in overproduction of pro‐inflammatory enzymes and cytokines, which is crucial in the development of obesity‐related osteoarthritis (OA). However, there are only a few drugs that target the lipotoxicity of OA. Recent researches have documented that the traditional Chinese medicine, Sparstolonin B (Ssn B), exerted anti‐inflammatory effects in various diseases, but not yet in OA. On the basis of this evidence, our works purposed to evaluate the effect of Ssn B on free fatty acid (FFA) palmitate (PA)‐stimulated human osteoarthritic chondrocytes and obesity‐associated mouse OA model. We found that Ssn B suppressed PA‐triggered inflammatory response and extracellular matrix catabolism in a concentration‐dependent approach. In vivo, Ssn B treatment inhibited cartilage degeneration and subchondral bone calcification caused by joint mechanical imbalance and alleviated metabolic inflammation in obesity. Mechanistically, co‐immunoprecipitine and molecular docking analysis showed that the formation of toll­like receptor 4 (TLR4)/myeloid differentiation protein‐2 (MD‐2) complex caused by PA was blocked by Ssn B. Subsequently, it leads to inactivation of PA‐caused myeloid differentiation factor 88 (MyD88)‐dependent nuclear factor‐kappaB (NF‐κB) cascade. Together, these findings demonstrated that Ssn B is a potential treatment agent for joint degenerative diseases in obese individuals.

Host gut microbiome and potential therapeutics in Gulf War Illness: A short review

AIMS

Since our troops had returned from the first Persian Gulf War in 1990-91, the veterans have reported chronic multisymptomatic illness widely referred to as Gulf War Illness (GWI). We aim to review the current directions of GWI pathology research in the context of chronic multisymptomatic illness and its possible gut microbiome targeted therapies. The veterans of Gulf War show symptoms of chronic fatigue, cognitive deficits, and a subsection report of gastrointestinal complications.

METHOD

Efforts of finding a suitable treatment regimen and clinical management remain a challenge. More recently, we have shown that the pathology is connected to alterations in the gut microbiome, and efforts of finding a suitable regimen for gut-directed therapeutics are underway. We discuss the various clinical interventions and summarize the possible effectiveness of gut-directed therapies such as the use of short-chain fatty acids (SCFA), phenolic compounds, and their metabolites, use of probiotics, and fecal microbiota transfer.

SIGNIFICANCE

The short review will be helpful to GWI researchers to expand their studies to the gut and find an effective treatment strategy for chronic multisymptomatic illness.

Sparstolonin B Exerts Therapeutic Effects on Collagen-Induced Arthritis by Inhibiting the NLRP3 Inflammasome and Reducing the Activity of α1,3-Fucosyltransferase

Objective. To explore the role of α1,3-fucosyltransferase in the mediation of rheumatoid arthritic inflammation, the protective effect of Sparstolonin B on rheumatoid arthritis (RA), and the mechanisms that regulate the NLRP3 inflammasome. Methods. Forty, weighing from 260-300 g, male Sprague-Dawley rats were randomly divided into the following groups: a sham operation group (Sham group), a rheumatoid arthritis model group (RA group), an RA+Sparstolonin B treatment group (RAS group), an RA+Iguratimod group (RAI group), and an RA+SsnB+NLRP3 inflammasome activator (Nigericin) group (RASN group); ten animals were allocated to each group. We determined the arthritis index for each group of rats, and pathological changes were evaluated by hematoxylin-eosin staining. We also used ELISAs to determine the serum levels of IL-17, IL-6, TNF-α, TGF-β, IL-18, and IL-1β. TUNEL staining was used to investigate apoptosis in synovial cells. IF was used to detect the release of ROS, ASC formation, and the expression levels of FucT-V and NLRP3. Western blotting was used to detect the protein expression levels of Bc1-2, Bax, TLR4, MYD88, NF-κB, pro-caspase-1, NLRP3, FucT-V, E-Selectin, and P-Selectin. We also performed in vitro experiments with Sparstolonin B and detected changes in 1,3-fucosyltransferase activity by ELISA. The pyroptosis-related phenotype, including ASC, was identified by immunofluorescence, while levels of NLRP-3, pro-IL-1, and pro-caspase-1 were detected by western blotting. Results. Sparstolonin B was showed to alleviate joint swelling in RA rats, inhibited inflammatory cell infiltration and the release of ROS, reduced damage caused by oxidative stress, and suppressed the rate of apoptosis in synovial cells. The administration of Sparstolonin B inhibited the secretion of IL-17 from Th17 cells and triggered the secretion of TGF-β from Treg cells, thus leading to the reduced expression of TLR4, MyD88, and NF-κB, and the suppression of TNF-α secretion. Moreover, Sparstolonin B downregulated the expression of NLRP3, inhibited ASC formation in vivo and in vitro, and reduced the levels of IL-18 and IL-1β. The expression levels of FucT-V, E-Selectin, and P-Selectin were also inhibited. Interestingly, these protective effects of Sparstolonin B could be blocked in RA rats by inhibiting the activation of the NLRP3 inflammasome. Conclusion. Sparstolonin B improved inflammatory responses and oxidative stress by inhibiting the NLRP3 inflammasome, inhibiting the expression of FucT-V and downregulating the TLR4/MYD88/NF-𝜅B signaling pathway in order to rescue RA.

Sparstolonin B exerts beneficial effects on prostate cancer by acting on the reactive oxygen species-mediated PI3K/AKT pathway

Prostate cancer is a major health concern in males worldwide, owing to its high incidence. Sparstolonin B (SsnB), a component of the Chinese herbal medicine Sparganium stoloniferum, is used to treat many diseases. However, the effects and mechanisms of action of SsnB in prostate cancer have not yet been reported. In this study, we evaluated the effects of SsnB on cellular processes and tumour growth. In particular, we verified that SsnB could inhibit the proliferation, migration and invasion of prostate cancer cells and induce apoptosis by activating G2/M phase arrest in vitro based on a series of cytological experiments. In vivo, we found that SsnB could inhibit tumour growth in nude mouse xenograft models. We further confirmed that SsnB could repress the PI3K/AKT pathway by increasing reactive oxygen species (ROS) accumulation and oxidative stress. Collectively, SsnB inhibits tumour growth and induces apoptosis in prostate cancer via the suppression of the ROS‐mediated PI3K/AKT pathway and may be a new alternative to adjuvant therapy for prostate cancer.

Forkhead box protein O1 (FoxO1) /SERPINB1 ameliorates ROS production in diabetic nephropathy

With the increasing prevalence of diabetes in recent years, diabetic nephropathy (DN) has become a severe disease that greatly threatens human health. DN not only is a common complication of diabetes, but also takes an important place in kidney disease. To this end, the present study was designed to explore the effects of Forkhead box protein O1 (FoxO1) on reactive oxygen species (ROS) production in DN mice. DN mice were treated with recombinant protein of FoxO1. Afterward, inflammation ELISA kits were used to measure the levels of TNF-α, IL-1β, IL-6, and IL-18. The levels of MDA, SOD, GSH, and GSH-PX were measured using kits according to the manufacturer's instructions. In addition, the production of ROS was assessed. Interestingly, the expression of FoxO1 was down-regulated in DN mice. The treatment of FoxO1 recombinant protein ameliorated MDA levels, increased the levels of SOD, GSH, and GSH-PX, and induced both mRNA and protein expression of hepatic serine protease inhibitor B1 (serpinB1) in ND mice. Similarly, FoxO1 reduced MDA levels and ROS production, increased the levels of SOD, GSH, and GSH-PXs, and induced the mRNA and protein expression of serpinB1 in in vitro model of DN. The inhibition of serpinB1 attenuated the effects of FoxO1 on ROS production-induced oxidative stress in in vitro model of DN. Overall, FoxO1/SERPINB1 ameliorated ROS production-induced oxidative stress in DN.

Sparstolonin B: A Unique Anti-Inflammatory Agent

Toll-like receptors are transmembrane proteins which sense and transmit infectious and inflammatory responses to the cells expressing them. Therapeutic strategies for the blockade of excessive Toll-like receptor signaling are being actively pursued for several diseases. Recently, Sparstolonin B, isolated from Chinese herb, which suppresses selectively Toll-like receptors has been studied in various inflammatory models. The objective of this review is to summarize the current literature regarding the use of Sparstolonin B in various in vitro and in vivo studies and to provide an overview regarding the potential use of this agent in different inflammatory diseases. Additionally, the current knowledge regarding the role of Toll-like receptors in inflammatory disease and the usage of various Toll-like receptor antagonists will be summarized. Based on our review, we believe Sparstolonin B could serve as a potential therapeutic agent for treatment of Toll-like receptor-mediated inflammatory disorders.

TLR Antagonism by Sparstolonin B Alters Microbial Signature and Modulates Gastrointestinal and Neuronal Inflammation in Gulf War Illness Preclinical Model

The 1991 Persian Gulf War veterans presented a myriad of symptoms that ranged from chronic pain, fatigue, gastrointestinal disturbances, and cognitive deficits. Currently, no therapeutic regimen exists to treat the plethora of chronic symptoms though newer pharmacological targets such as microbiome have been identified recently. Toll-like receptor 4 (TLR4) antagonism in systemic inflammatory diseases have been tried before with limited success, but strategies with broad-spectrum TLR4 antagonists and their ability to modulate the host-microbiome have been elusive. Using a mouse model of Gulf War Illness, we show that a nutraceutical, derived from a Chinese herb Sparstolonin B (SsnB) presented a unique microbiome signature with an increased abundance of butyrogenic bacteria. SsnB administration restored a normal tight junction protein profile with an increase in Occludin and a parallel decrease in Claudin 2 and inflammatory mediators high mobility group box 1 (HMGB1), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in the distal intestine. SsnB also decreased neuronal inflammation by decreasing IL-1β and HMGB1, while increasing brain-derived neurotrophic factor (BDNF), with a parallel decrease in astrocyte activation in vitro. Mechanistically, SsnB inhibited the binding of HMGB1 and myeloid differentiation primary response protein (MyD88) to TLR4 in the intestine, thus attenuating TLR4 downstream signaling. Studies also showed that SsnB was effective in suppressing TLR4-induced nod-like receptor protein 3 (NLRP3) inflammasome activation, a prominent inflammatory disease pathway. SsnB significantly decreased astrocyte activation by decreasing colocalization of glial fibrillary acid protein (GFAP) and S100 calcium-binding protein B (S100B), a crucial event in neuronal inflammation. Inactivation of SsnB by treating the parent molecule by acetate reversed the deactivation of NLRP3 inflammasome and astrocytes in vitro, suggesting that SsnB molecular motifs may be responsible for its anti-inflammatory activity.

Antipruritic effects of electroacupuncture on morphine-induced pruritus model mice through the TLR2/4-MyD88-NF-κB pathway

Pruritus is one of the common side effects of intrathecal or epidural injection of opioids. The aim of this study was to test the antipruritic effect of acupuncture and its possible mechanism. We used electroacupuncture (EA), toll-like receptor (TLR)2/4 antagonist sparstolonin B (SsnB), and TLR2/4 agonist peptidoglycan (PGN) to precondition female wild-type BALB/c mice, and then prepared a morphine-induced pruritus model. The mRNA and protein expression levels of TLR2, TLR4, MyD88, and NF-κB were detected by RT-PCR and western blotting. The contents of interleukin (IL)-1, IL-6, IL-12, IL-10, and tumor necrosis factor-α in serum were measured by ELISA assays. Flow cytometry was performed to analyze the ratio of M1-phenotype to M2-phenotype macrophages. Our results showed that EA preconditioning improved pruritus; reduced the expressions of TLR2, TLR4, MyD88, and NF-κB both at the mRNA and protein levels (P<0.05); reduced the expression of proinflammatory cytokines IL-1, IL-6, IL-12, and tumor necrosis factor-α; and increased the expression of anti-inflammatory cytokine IL-10 (P<0.05). EA promoted M2-phenotype macrophage differentiation. Moreover, these results showed no significant difference between the SsnB group and the EA+SsnB group (P>0.05), but showed a significant difference between the PGN group and the EA+PGN group (P<0.05). Therefore, we propose that EA may be involved in the remission of pruritus in morphine-induced pruritus model mice through the TLR2/4-MyD88-NF-κB pathway. EA is a potential therapeutic treatment for pruritus.

Altered Toll-Like Receptor Signalling in Children with Down Syndrome

Toll-like receptors (TLRs) are the key in initiating innate immune responses. TLR2 is crucial in recognising lipopeptides from gram-positive bacteria and is implicated in chronic inflammation. Children with Down syndrome (DS) are prone to infections from these pathogens and have an increased risk of autoimmunity. Sparstolonin B (SsnB) is a TLR antagonist which attenuates cytokine production and improves outcomes in sepsis. We hypothesised that TLR signalling may be abnormal in children with DS and contribute to their clinical phenotype. We evaluated TLR pathways in 3 ways: determining the expression of TLR2 on the surface of neutrophils and monocytes by flow cytometry, examining the gene expression of key regulatory proteins involved in TLR signal propagation, MyD88, IRAK4, and TRIF, by quantitative PCR, and lastly determining the cytokine production by ELISA following immunomodulation with proinflammatory stimuli (lipopolysaccharide (LPS), Pam3Csk4) and the anti-inflammatory agent SsnB. We report TLR2 expression being significantly increased on neutrophils, total monocytes, and intermediate and nonclassical monocytes in children with DS (n = 20, mean age 8.8 ± SD 5.3 years, female n = 11) compared to controls (n = 15, mean age 6.2 ± 4.2 years, female n = 5). At baseline, the expression of MyD88 was significantly lower, and TRIF significantly raised in children with DS. The TLR antagonist SsnB was effective in reducing TLR2 and CD11b expression and abrogating cytokine production in both cohorts. We conclude that TLR signalling and the TLR2 pathway are dysregulated in DS, and this disparate innate immunity may contribute to chronic inflammation in DS. SsnB attenuates proinflammatory mediators and may be of therapeutic benefit.

SIRT1 inhibits apoptosis in in vivo and in vitro models of spinal cord injury via microRNA-494

The aim of the present study was to investigate the function and mechanism of sirtuin 1 (SIRT1) in spinal cord injury (SCI). Reverse transcription-quantitative polymerase chain reaction was used to measure the expression levels of microRNA (miR)-494. MTT assay, lactate dehydrogenase activity assay and flow cytometry were used to analyze the effects of miR-494 on cell growth and apoptosis in a model of SCI. The present study demonstrated that SIRT1 expression was reduced; whereas miR-494 expression was increased in a rat model of SCI. Overexpression of miR-494 suppressed the protein expression levels of SIRT1, and induced p53 protein expression. Conversely, knockdown of miR-494 induced SIRT1 protein expression in an in vitro model of SCI. Furthermore, overexpression of miR-494 promoted cell apoptosis and decreased cell growth in an in vitro model of SCI; however, miR-494 knockdown enhanced cell growth and inhibited cell apoptosis. Administration of a SIRT1 agonist reduced the effects of miR-494 overexpression on cell apoptosis in an SCI model, whereas treatment with a p53 agonist reduced the effects of miR-494 knockdown on cell apoptosis in an SCI model. Together, these findings suggested that SIRT1 may inhibit apoptosis of SCI in vivo and in vitro through the p53 signaling pathway, whereas miR-494 suppressed SIRT1 and induced apoptosis.

The active fraction from the tuber of Bolboschoenus yagara inhibits melanoma B16 cells metastasis LPS-induced in vitro and in vivo

This study was to identify anti-metastatic active fractions and compounds of Bolboschoenus yagara (B. yagara). The results indicated that 50 µg/mL ethyl acetate fraction (Et) can dramatically inhibit mouse melanoma B16 cells migration and invasion in vitro. In B16 cells pulmonary and hepatic metastasis assays, 50 µg/mL Et alleviated mouse lung and liver weights, the number of metastatic nodules and the levels of TNF-α and IL-6 in mouse serum and organs. Histological studies showed that Et fraction was able to prevent liver and lung metastasis. And the inhibition of 50 µg/mL Et fraction against hepatic metastasis was almost equivalent to that of 1 µM TAK242. In addition, fourteen compounds of Et were quantified by HPLC analysis, in which, isocoumarins, stilbenes and xanthones obviously abated LPS-modulated B16 cells migration and invasion.[Formula: see text].

Sparstolonin B (SsnB) attenuates liver fibrosis via a parallel conjugate pathway involving P53-P21 axis, TGF-beta signaling and focal adhesion that is TLR4 dependent

SsnB previously showed a promising role to lessen liver inflammation observed in a mouse model of NAFLD. Since NAFLD can progress to fibrosis, studies were designed to unravel its role in attenuating NAFLD associated fibrosis. Using both in vivo and in vitro approaches, the study probed the possible mechanisms that underlined the role of SsnB in mitigating fibrosis. Mechanistically, SsnB, a TLR4 antagonist, decreased TLR4-PI3k akt signaling by upregulating PTEN protein expression. It also decreased MDM2 protein activation and increased p53 and p21 gene and protein expression. SsnB also downregulated pro-fibrogenic hedgehog signaling pathway, inhibited hepatic stellate cell proliferation and induced apoptosis in hepatic stellate cells, a mechanism that was LPS dependent. Further, SsnB decreased fibrosis by antagonizing TLR4 induced TGFβ signaling pathway. Alternatively, SsnB augmented BAMBI (a TGFβ pseudo-receptor) expression in mice liver by inhibiting TLR4 signaling pathway and thus reduced TGFβ signaling, resulting in decreased hepatic stellate cell activation and extracellular matrix deposition. In vitro experiments on human hepatic stellate cell line showed that SsnB increased gene and protein expression of BAMBI. It also decreased nuclear co-localization of phospho SMAD2/3 and SMAD4 protein and thus attenuated TGFβ signaling in vitro. We also observed a significant decrease in phosphorylation of SMAD2/3 protein, decreased STAT3 activation, alteration of focal adhesion protein and stress fiber disassembly upon SsnB administration in hepatic stellate cells which further confirmed the antagonistic effect of SsnB on TLR4-induced fibrogenesis.

Toll-Like Receptor 2 Signaling and Current Approaches for Therapeutic Modulation in Synucleinopathies

The innate immune response in the central nervous system (CNS) is implicated as both beneficial and detrimental to health. Integral to this process are microglia, the resident immune cells of the CNS. Microglia express a wide variety of pattern-recognition receptors, such as Toll-like receptors, that detect changes in the neural environment. The activation of microglia and the subsequent proinflammatory response has become increasingly relevant to synucleinopathies, including Parkinson's disease the second most prevalent neurodegenerative disease. Within these diseases there is evidence of the accumulation of endogenous α-synuclein that stimulates an inflammatory response from microglia via the Toll-like receptors. There have been recent developments in both new and old pharmacological agents designed to target microglia and curtail the inflammatory environment. This review will aim to delineate the process of microglia-mediated inflammation and new therapeutic avenues to manage the response.

Sparstolonin B improves neurological outcomes following intracerebral hemorrhage in mice

Inflammation serves an important role in inducing secondary injury following intracerebral hemorrhage (ICH). It has been demonstrated that sparstolonin B (SsnB) is able to attenuate the lipopolysaccharide-induced inflammatory response in sepsis. Mouse ICH models were used to explore the efficacy of SsnB on the ICH-induced inflammatory response. Mice underwent a working memory version of Morris water maze (MWM) test. They underwent 5 successive days of training consisting of 4 trials each day. The ICH model was established on the last training day. Mice were injected intraperitoneally either with vehicle or SsnB once a day for 3 consecutive days following the establishment of the ICH model. The MWM was used to determine the effect of SsnB on short-term memory following ICH. Neurological deficit scores and brain water content were measured following the MWM. Furthermore, the expression of inflammatory factors and signaling molecules downstream of TLR4 were measured. The results demonstrated that 5 mg/kg SsnB significantly improved the MWM path and time latency (P<0.05). Furthermore, neurological deficit scores were decreased in SsnB-treated mice compared with vehicle-treated mice (P<0.01). Brain water content, levels of inflammatory cytokines and the expression of inflammation-associated proteins were also significantly reduced in the SsnB-treated group (P<0.05). These results indicate that SsnB treatment stimulates short-term neurobehavioral recovery and reduces neurological deficits and this may inhibit the inflammatory response. Therefore, SsnB may attenuate the inflammatory response following ICH.

Sparstolonin B attenuates spinal cord injury‑induced inflammation in rats by modulating TLR4‑trafficking

The present study used a spinal cord injury (SCI) model to evaluate whether sparstolonin B was able to prevent SCI, and to investigate the underlying signaling mechanism. Sparstolonin B attenuated the SCI‑induced Batto, Beattie and Bresnahan score and water content in rats. Sparstolonin B attenuated the mRNA expression of proinflammatory cytokines interleukin (IL)‑18, IL‑6, IL‑1β, and IL‑23, decreased the levels of tumor necrosis factor‑α and interferon‑γ, and decreased caspase‑3 activity and apoptosis regulator Bax protein expression in SCI rats. Similarly, sparstolonin B inhibited monocyte chemoattractant protein‑1 mRNA levels, and Toll‑like receptor (TLR) 4, myeloid differentiation primary response protein MyD88 (MyD88) and nuclear factor (NF)‑κB protein levels in SCI rats. The present results suggested that sparstolonin B may attenuate SCI‑induced inflammation and apoptosis in rats by modulating the TLR4/MyD88/NF‑κB signaling pathway.

Inhibition of p38 and ERK1/2 pathways by Sparstolonin B suppresses inflammation-induced melanoma metastasis

BACKGROUND

Cancer related inflammation plays a fatal role in the metastatic process, which can foster tumor growth, angiogenesis and dissemination. Sparstolonin B (SsnB), derived from Chinese medicine of the tubers of Scirpus yagara, is a TLR2 and TLR4 antagonists. It has exhibited multiple activities of anti-inflammatory, anti-cancer, anti-obesity and anti-hepatitis. However, whether SsnB is involved in the regulation of inflammation-induced tumor metastasis is not well elucidated.

PURPOSE

The aim of this study was to investigate the effectiveness of SsnB as a treatment of inflammation-induced tumor metastasis and identify the underlying mechanisms of its anti-tumor metastatic activity.

METHOD

The anti-tumor metastatic activity in vitro was estimated by MTT, wound-healing assay, matrigel invasion analysis and extracellular matrix adhesion assay. Mice lung metastasis and hepatic metastasis experiments were performed to assess the activities in vivo. Lungs or livers were weighed and the number of metastatic nodules was determined after mice were sacrificed. The levels of pro-inflammatory cytokines in the serum, lungs and livers were detected by using enzyme-linked immunosorbent assay (ELISA). Micro-metastasis nodules in lungs or livers were analyzed by histological examination. Immunohistochemistry and western blot analysis were conducted to determine protein expression.

RESULT

Herein, SsnB dose-dependently inhibited cell migration and invasion in mouse melanoma B16 cells with or without stimulation of lipopolysaccharide (LPS), Pam3csk4 or molecules from damaged tumor cells (DTC-Ms). The expression of matrix metalloproteinases (MMP)-2 was also significantly abated by SsnB in LPS-modulated B16 cells. And SsnB reduced LPS-activated B16 cells adhesion to extracellular matrix components collagen I and fibronectin in a dose-dependent manner. In vivo, SsnB obviously attenuated LPS-activated pulmonary metastasis in mice by reduction the number of metastatic nodules on the lung surfaces, lung weight and levels of tumor necrosis factor (TNF)-α and interleukin (IL)-6 in serums and lungs. Moreover, in experimental hepatic metastasis model mice, SsnB remarkably repressed LPS-stimulated the number of metastatic nodules along with liver weight; and SsnB significantly suppressed LPS-activated increase levels of TNF-α and IL-6 in livers. Immunohistochemistry analysis indicated that SsnB inhibited the expression of TLR4 in livers. Furthermore, SsnB remarkably blocked p38 and ERK1/2 signaling pathway in LPS-induced B16 cells. P38 and ERK1/2 signaling silencing, using BIRB0796 (small molecular inhibitor of p38 MAPK) and PD184352 (inhibitor of MEK1/2 kinases that activate ERK1/2), significantly abated LPS-induced migration and invasion of B16 cells.

CONCLUSION

The present study reports a novel use of SsnB in mitigating TLRs ligands-induced melanoma metastasis by inhibition of p38 and ERK1/2 pathway.

TLR4 Signaling Pathway Modulators as Potential Therapeutics in Inflammation and Sepsis

Toll-Like Receptor 4 (TLR4) signal pathway plays an important role in initiating the innate immune response and its activation by bacterial endotoxin is responsible for chronic and acute inflammatory disorders that are becoming more and more frequent in developed countries. Modulation of the TLR4 pathway is a potential strategy to specifically target these pathologies. Among the diseases caused by TLR4 abnormal activation by bacterial endotoxin, sepsis is the most dangerous one because it is a life-threatening acute system inflammatory condition that still lacks specific pharmacological treatment. Here, we review molecules at a preclinical or clinical phase of development, that are active in inhibiting the TLR4-MyD88 and TLR4-TRIF pathways in animal models. These are low-molecular weight compounds of natural and synthetic origin that can be considered leads for drug development. The results of in vivo studies in the sepsis model and the mechanisms of action of drug leads are presented and critically discussed, evidencing the differences in treatment results from rodents to humans.

Chronoinflammaging in Alzheimer; A systematic review on the roles of toll like receptor 2

Aging is associated with a range of chronic low-grade inflammation (Chronoinflammaging) which may play a significant role in some chronic inflammatory based diseases, such as Alzheimer disease (AD). However, the events which lead to the induction of chronoinflammaging in AD are yet to be clarified. It has been proposed that the recognition of endogenous ligands by pathogen recognition receptors (PRRs) may be involved in the induction of chronoinflammaging. Toll like receptors (TLRs) are a family of PRRs which recognize endogenous damage associated molecular patterns (DAMPs) and subsequently induce inflammation. Therefore, TLRs are worthy of investigation to elucidate their roles in chronoinflammaging associated AD. This review article explores the main roles played by TLR2 in the pathogenesis of chronoinflammaging in patients suffering from AD.

Sparstolonin B attenuates early liver inflammation in experimental NASH by modulating TLR4 trafficking in lipid rafts via NADPH oxidase activation

Although significant research data exist on the pathophysiology of nonalcoholic steatohepatitis (NASH), finding an efficient treatment regimen for it remains elusive. The present study used sparstolonin B (SsnB), a novel TLR4 antagonist derived from the Chinese herb Sparganium stoloniferum, as a possible drug to mitigate early inflammation in NASH. This study used an early steatohepatitic injury model in high-fat-fed mice with CYP2E1-mediated oxidative stress as a second hit. SsnB was administered for 1 wk along with bromodichloromethane (BDCM), an inducer of CYP2E1-mediated oxidative stress. Results showed that SsnB administration attenuated inflammatory morphology and decreased elevation of the liver enzyme alanine aminotransferase (ALT). Mice administered SsnB also showed decreased mRNA expression of proinflammatory cytokines TNF-α, IFN-γ, IL-1β, and IL-23, while protein levels of both TNF-α and IL-1β were significantly decreased. SsnB significantly decreased Kupffer cell activation as evidenced by reduction in CD68 and monocyte chemoattractant protein-1 (MCP1) mRNA and protein levels with concomitant inhibition of macrophage infiltration in the injured liver. Mechanistically, SsnB decreased TLR4 trafficking to the lipid rafts, a phenomenon described by the colocalization of TLR4 and lipid raft marker flotillin in tissues and immortalized Kupffer cells. Since we have shown previously that NADPH oxidase drives TLR4 trafficking in NASH, we studied the role of SsnB in modulating this pathway. SsnB prevented NADPH oxidase activation in vivo and in vitro as indicated by decreased peroxynitrite formation. In summary, the present study reports a novel use of the TLR4 antagonist SsnB in mitigating inflammation in NASH and in parallel shows a unique molecular mechanism of decreasing nitrative stress.