Sophocarpine Protects Mice from ConA-Induced Hepatitis via Inhibition of the IFN-Gamma/STAT1 Pathway

Purple sweet potato polysaccharide ameliorates concanavalin A-induced hepatic injury by inhibiting inflammation and oxidative stress

BACKGROUND

Autoimmune hepatitis (AIH) is a prevalent liver disease that can potentially lead to hepatic fibrosis and cirrhosis. The prolonged administration of immunosuppressive medications carries significant risks for patients. Purple sweet potato polysaccharide (PSPP), a macromolecule stored in root tubers, exhibits anti-inflammatory, antioxidant, immune-enhancing, and intestinal flora-regulating properties. Nevertheless, investigation into the role and potential mechanisms of PSPP in AIH remains notably scarce.

PURPOSE

Our aim was to explore the possible protective impacts of PSPP against concanavalin A (Con A)-induced liver injury in mice.

METHODS

Polysaccharide was isolated from purple sweet potato tubers using water extraction and alcohol precipitation, followed by purification through DEAE-52 cellulose column chromatography and Sephadex G-100 column chromatography. A highly purified component was obtained, and its monosaccharide composition was characterized by high performance liquid chromatography (HPLC). Mouse and cellular models induced by Con A were set up to investigate the impacts of PSPP on hepatic histopathology, apoptosis, as well as inflammation- and oxidative stress-related proteins in response to PSPP treatment.

RESULTS

The administration of PSPP significantly reduced hepatic pathological damage, suppressed elevation of ALT and AST levels, and attenuated hepatic apoptosis in Con A-exposed mice. PSPP was found to mitigate Con A-induced inflammation by suppressing the TLR4-P2X7R/NLRP3 signaling pathway in mice. Furthermore, PSPP alleviated Con A-induced oxidative stress by activating the PI3K/AKT/mTOR signaling pathway in mice. Additionally, PSPP demonstrated the ability to reduce inflammation and oxidative stress in RAW264.7 cells induced by Con A in vitro.

CONCLUSION

PSPP has the potential to ameliorate hepatic inflammation via the TLR4-P2X7R/NLRP3 pathway and inhibit hepatic oxidative stress through the PI3K/AKT/mTOR pathway during the progression of Con A-induced hepatic injury. The results of this study have unveiled the potential hepatoprotective properties of purple sweet potato and its medicinal value for humans. Moreover, this study serves as a valuable reference, highlighting the potential of PSPP-1 as a drug candidate for the treatment of immune liver injury.

A review on the pharmacology, pharmacokinetics and toxicity of sophocarpine

Sophocarpine is a natural compound that belongs to the quinolizidine alkaloid family, and has a long history of use and widespread distribution in traditional Chinese herbal medicines such as Sophora alopecuroides L., Sophora flavescens Ait., and Sophora subprostrata. This article aims to summarize the pharmacology, pharmacokinetics, and toxicity of sophocarpine, evaluate its potential pharmacological effects in various diseases, and propose the necessity for further research and evaluation to promote its clinical application. A large number of studies have shown that it has anti-inflammatory, analgesic, antiviral, antiparasitic, anticancer, endocrine regulatory, and organ-protective effects as it modulates various signaling pathways, such as the NF-κB, MAPK, PI3K/AKT, and AMPK pathways. The distribution of sophocarpine in the body conforms to a two-compartment model, and sophocarpine can be detected in various tissues with a relatively short half-life. Although the pharmacological effects of sophocarpine have been confirmed, toxicity and safety assessments and reports on molecular mechanisms of its pharmacological actions have been limited. Given its significant pharmacological effects and potential clinical value, further research and evaluation are needed to promote the clinical application of sophocarpine.

Antibody-Conjugated Magnetic Nanoparticle Therapy for Inhibiting T-Cell Mediated Inflammation

Tolerance induction is critical for mitigating T cell-mediated inflammation. Treatments based on anti-CD3 monoclonal antibody (mAb) play a pivotal role in inducing such tolerance. Anti-CD3 mAb conjugated with dextran-coated magnetic nanoparticles (MNPs) may induce inflammatory tolerance is posited. MNPs conjugated with anti-CD3 mAb (Ab-MNPs) are characterized using transmission and scanning electron microscopy, and their distribution is assessed using a nanoparticle tracking analyzer. Compared to MNPs, 90% of Ab-MNPs increased in size from 54.7 ± 0.5 to 71.7 ± 2.7 nm. The in vitro and in vivo studies confirmed the therapeutic material as nontoxic and biocompatible. Mice are administered various dosages of Ab-MNPs before receiving concanavalin-A (ConA), an inflammation inducer. Preadministration of Ab-MNPs, as opposed to MNPs or anti-CD3 mAb alone, significantly reduced the serum levels of interferon-γ and interleukin-6 in ConA-treated mice. Additionally, the transdermal stamp patch as an effective delivery system for Ab-MNPs is validated. This study demonstrates the utility of the Ab-MNP complex in pathologies associated with T cell-mediated hyperinflammation, such as organ transplantation and COVID-19.

Enhancing Liver Delivery of Gold Nanoclusters via Human Serum Albumin Encapsulation for Autoimmune Hepatitis Alleviation

Peptide-protected gold nanoclusters (AuNCs), possessing exceptional biocompatibility and remarkable physicochemical properties, have demonstrated intrinsic pharmaceutical activity in immunomodulation, making them a highly attractive frontier in the field of nanomedicine exploration. Autoimmune hepatitis (AIH) is a serious autoimmune liver disease caused by the disruption of immune balance, for which effective treatment options are still lacking. In this study, we initially identified glutathione (GSH)-protected AuNCs as a promising nanodrug candidate for AIH alleviating in a Concanavalin A (Con A)-induced mice model. However, to enhance treatment efficiency, liver-targeted delivery needs to be improved. Therefore, human serum albumin (HSA)-encapsulated AuNCs were constructed to achieve enhanced liver targeting and more potent mitigation of Con A-induced elevations in plasma aspartate transaminase (AST), alanine transaminase (ALT), and liver injury in mice. In vivo and in vitro mechanism studies indicated that AuNCs could suppress the secretion of IFN-γ by Con A-stimulated T cells and subsequently inhibit the activation of the JAK2/STAT1 pathway and eventual hepatocyte apoptosis induced by IFN-γ. These actions ultimately protect the liver from immune cell infiltration and damage caused by Con A. These findings suggest that bio-protected AuNCs hold promise as nanodrugs for AIH therapy, with their liver targeting capabilities and therapeutic efficiency being further improved via rational surface ligand engineering.

Cornuside improves murine autoimmune hepatitis through inhibition of inflammatory responses

BACKGROUND

Autoimmune hepatitis (AIH) poses an important public health concern worldwide, with few therapeutic options available. Cornuside, a primary cornel iridoid glycoside present in Cornus officinalis Sieb. et Zucc., is a well-known traditional Chinese medicine that possesses anti-inflammatory, antioxidant and anti-apoptotic properties. However, the effects of cornuside on autoimmune diseases including AIH is still not defined, neither is clear on the mechanisms of cornuside in the suppression of inflammatory responses.

PURPOSE

The study was aimed to investigate the therapeutic effects of cornuside on AIH using murine models.

STUDY DESIGN

A murine model of AIH induced by concanavalin A (Con A) was used to examine the pharmacological activity of cornuside in suppressing the inflammatory responses in vivo.

METHODS

C57BL/6J mice were intravenously with different doses of cornuside and challenged with 18 mg/kg Con A 3 h later. Network pharmacological analysis was performed to identify the potential target genes and signaling pathways by cornuside in AIH. Next serum and liver tissues were collected 12 h after Con A injection to analyze the levels of markers for hepatic injury, apoptosis, oxidative stress, immune responses, and inflammation.

RESULTS

Network pharmacological analysis revealed that cornuside may modulate oxidative stress and apoptosis in AIH. Compared with the Con A group, cornuside pretreatment significantly reduced the serum levels of alanine aminotransferase and aspartate aminotransferase, improving histopathological damage and apoptosis in the livers. In addition, cornuside decreased the levels of malondialdehyde, myeloperoxidase, but increased superoxide dismutase levels, suggesting the relieving of oxidative stress. Furthermore, cornuside suppressed the activation of T and natural killer T cells, whereas the proportion of myeloid-derived suppressor cells was significantly increased. The production of proinflammatory cytokines, including interleukin (IL)-6, IL-12, IL-1β, and tumor necrosis factor-alpha (TNF-α), was also clearly decreased. Finally, western blot analysis displayed that cornuside inhibited the phosphorylation of extracellular receptor kinase (ERK) and c-Jun N-terminal kinase (JNK).

CONCLUSIONS

We demonstrated that cornuside has protective effects for Con A-induced immune-mediated hepatitis by suppressing the oxidative stress, apoptosis, and the inflammatory responses through the ERK and JNK signaling pathways, as well as by modulating the activation and recruitment of immune cells.

Concanavalin A promotes angiogenesis and proliferation in endothelial cells through the Akt/ERK/Cyclin D1 axis

CONTEXT

Concanavalin A (Con A) exhibited multiple roles in cancer cells. However, the role of Con A in endothelial cells was not reported.

OBJECTIVE

Our present study investigated the potential angiogenic role of Con A in endothelial cells and ischaemic hind-limb mice.

MATERIALS AND METHODS

Human umbilical vein endothelial cells and Ea.hy926 cells were employed to determine the effect of Con A (0.3, 1, and 3 μg/mL) or vehicle on angiogenesis and cell proliferation with tube formation, ELISA, flow cytometry, EdU, and western blot. Hind-limb ischaemic mice were conducted to determine the pro-angiogenic effect of Con A (10 mg/kg) for 7 days.

RESULTS

Con A promoted tube formation to about three-fold higher than the control group and increased the secretion of VEGFa, PDGFaa, and bFGF in the medium. The cell viability was promoted to 1.3-fold by Con A 3 μg/mL, and cell cycle progression of G0G1 phase was decreased from 77% in the vehicle group to 70% in Con A 3 μg/mL, G2M was promoted from 15 to 19%, and S-phase was from 7 to 10%. Con A significantly stimulated phosphorylation of Akt and ERK1/2 and expression of cyclin D1 and decreased the expression of p27. These effects of Con A were antagonised by the PI3K inhibitor LY294002 (10 μM) and MEK pathway antagonist PD98059 (10 μM). Moreover, Con A (10 mg/kg) exhibited a repair effect in ischaemic hind-limb mice.

DISCUSSION AND CONCLUSIONS

This study will provide a new option for treating ischaemic disease by local injection with Con A.

Drug Candidates for Autoimmune Diseases

Most of the immunosuppressive drugs used in the clinic to prevent organ rejection or to treat autoimmune disorders were originally isolated from fungi or bacteria. Therefore, in addition to plants, these are valuable sources for identification of new potent drugs. Many side effects of established drugs limit their usage and make the identification of new immunosuppressants necessary. In this review, we present a comprehensive overview of natural products with potent anti-inflammatory activities that have been tested successfully in different models of chronic inflammatory autoimmune diseases. Some of these candidates already have passed first clinical trials. The anti-inflammatory potency of these natural products was often comparable to those of established drugs, and they could be used at least in addition to standard therapy to reduce their dose to minimize unwanted side effects. A frequent mode of action is the inhibition of classical inflammatory signaling pathways, such as NF-κB, in combination with downregulation of oxidative stress. A drawback for the therapeutic use of those natural products is their moderate bioavailability, which can be optimized by chemical modifications and, in addition, further safety studies are necessary. Altogether, very interesting candidate compounds exist which have the potential to serve as starting points for the development of new immunosuppressive drugs.

Pathogenesis of Concanavalin A induced autoimmune hepatitis in mice

Autoimmune hepatitis (AIH) is an autoimmune disease characterized by liver parenchymal destruction and chronic fibrosis. Its exact etiology and pathogenesis are not yet fully understood.(Please connect with the following, do not leave a line) Concanavalin A (Con A)-induced mice hepatitis model is a liver injury mediated by T cell and macrophage activation, and its pathogenesis and pathological changes are similar to human AIH. The establishment of this model has greatly promoted the research progress of AIH pathogenesis. However, the exact mechanism of Con A induced liver injury in mice, and its possible defects or deficiencies, has not yet been described in a clear and detailed manner. Therefore, the model has some limitations when applied to the study of the pathogenesis and treatment mechanism of AIH. This article reveals the pathogenesis of Con A induced liver injury in mice from the aspects of immune disorder and coagulation mechanism, expounds the significance of non-coding RNA in this model, summarizes the signal transduction pathways involved in this model, and summarizes the advantages and disadvantages of the model, which provides a theoretical basis and research target for the application of Con A induced liver injury model in AIH in the future.

Thesium chinense Turcz.: An ethnomedical, phytochemical and pharmacological review

ETHNOPHARMACOLOGICAL RELEVANCE

Thesium chinense Turcz. has been used to treat mastitis, pulmonitis, tonsillitis, iaryngopharyngitis and upper respiratory tract infections in the indigenous medicine of China for a long history. Presently, several pharmaceutics prepared by this medical herb have been clinically used for the therapy of infectious diseases.

AIM OF THE REVIEW

This review aims to comprehensively summarize the current researches on the ethnomedical, phytochemical and pharmacological aspects of T. chinense, and discuss their possible opportunities for the future research.

MATERIALS AND METHODS

Extensive database searches, including Web of Science, SciFinder, Google Scholar and China Knowledge Resource Integrated, were performed using keywords such as 'Thesium chinense', 'Bai Rui Cao', and their chemical constituents. In addition, local classic herbal literature on ethnopharmacology and relevant textbooks were consulted to provide a comprehensive survey of this ethnomedicine.

RESULTS

Thirty four chemical constituents, including flavonoids, alkaloids, and terpenoids, have been identified from T. chinense. Of which, flavonoids are the predominant and characteristic constituents. The crude extracts, the purified constituents, and commercial available pharmaceutics have displayed diverse in vitro and in vivo pharmacological functions (e.g. anti-inflammation, antimicrobial activity, analgesic effect, hepaprotection), and are particularly useful as a potential therapeutic agent against inflammation-related diseases.

CONCLUSIONS

T. chinense is an important ethnomedical medicine and possesses a satisfying effect for treating inflammation, microbial infection, and upper respiratory diseases. It has received plenty of researches on its phytochemical and pharmacological aspects since 1970s. These findings definitely establish the link between chemical composition and pharmacological application, and support the ethnomedical use of T. chinense in the indigenous medicine of China. However, chemical composition of this plant and the molecular mechanisms of purified constituents have not been comprehensively investigated, and thus the trace constituents and the therapeutic targets of bioactive constituents deserve a further exploration. Collectively, the researchers should pay more attention to a better understanding and application of this ethnomedical plant.

PK/PD Modeling of the PDE7 Inhibitor-GRMS-55 in a Mouse Model of Autoimmune Hepatitis

This study aimed to assess the efficacy and explore the mechanisms of action of a potent phosphodiesterase (PDE)7A and a moderate PDE4B inhibitor GRMS-55 in a mouse model of autoimmune hepatitis (AIH). The concentrations of GRMS-55 and relevant biomarkers were measured in the serum of BALB/c mice with concanavalin A (ConA)-induced hepatitis administered with GRMS-55 at two dose levels. A semi-mechanistic PK/PD/disease progression model describing the time courses of measured biomarkers was developed. The emetogenicity as a potential side effect of the studied compound was evaluated in the α₂-adrenoceptor agonist-induced anesthesia model. The results indicate that liver damage observed in mice challenged with ConA was mainly mediated by TNF-α and IFN-γ. GRMS-55 decreased the levels of pro-inflammatory mediators and the transaminase activities in the serum of mice with AIH. The anti-inflammatory properties of GRMS-55, resulting mainly from PDE7A inhibition, led to a high hepatoprotective activity in mice with AIH, which was mediated by an inhibition of pro-inflammatory signaling. GRMS-55 did not induce the emetic-like behavior. The developed PK/PD/disease progression model may be used in future studies to assess the potency and explore the mechanisms of action of new investigational compounds for the treatment of AIH.

Hepatoprotective Effect of Mixture of Dipropyl Polysulfides in Concanavalin A-Induced Hepatitis

The main biologically active components of plants belonging to the genus Allium, responsible for their biological activities, including anti-inflammatory, antioxidant and immunomodulatory, are organosulfur compounds. The aim of this study was to synthetize the mixture of dipropyl polysulfides (DPPS) and to test their biological activity in acute hepatitis. C57BL/6 mice were administered orally with DPPS 6 h before intravenous injection of Concanavalin A (ConA). Liver inflammation, necrosis and hepatocytes apoptosis were determined by histological analyses. Cytokines in liver tissue were determined by ELISA, expression of adhesive molecules and enzymes by RT PCR, while liver mononuclear cells were analyzed by flow cytometry. DPPS pretreatment significantly attenuated liver inflammation and injury, as evidenced by biochemical and histopathological observations. In DPPS-pretreated mice, messenger RNA levels of adhesion molecules and NADPH oxidase complex were significantly reduced, while the expression of SOD enzymes was enhanced. DPPS pretreatment decreased protein level of inflammatory cytokines and increased percentage of T regulatory cells in the livers of ConA mice. DPPS showed hepatoprotective effects in ConA-induced hepatitis, characterized by attenuation of inflammation and affection of Th17/Treg balance in favor of T regulatory cells and implicating potential therapeutic usage of DPPS mixture in inflammatory liver diseases.

Treatment With Endothelin-A Receptor Antagonist BQ123 Attenuates Acute Inflammation in Mice Through T-Cell-Dependent Polymorphonuclear Myeloid-Derived Suppressor Cell Activation

The endothelin-A receptor antagonist BQ123 is an effective treatment agent for hypertension and obese cardiomyopathy. However, the role of BQ123 in controlling acute inflammatory diseases and its underlying mechanisms are not well understood. Here, we showed that BQ123 activated polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) in mice and that the IL13/STAT6/Arg1 signaling pathway is involved in this process. Importantly, both treatment with BQ123 and the transfer of BQ123-induced PMN-MDSCs (BQ123-MDSCs) were effective in relieving inflammation, including dextran sulfate sodium (DSS)-induced colitis, papain-induced pneumonia, and concanavalin A (ConA)-induced hepatitis, in mice. The treatment effects were mediated by the attenuation of the inflammation associated with the accumulation of PMN-MDSCs in the colon, lung, and liver. However, concurrent injection of Gr1 agonistic antibody with BQ123 induced PMN-MDSC aggravated the observed acute inflammation. Interestingly, no remission of inflammation was observed in Rag2 knockout mice administered BQ123-MDSCs, but co-injection with CD3⁺ T cells significantly relieved acute inflammation. In summary, BQ123-induced PMN-MDSCs attenuated acute inflammation in a T cell-dependent manner, providing a novel potential strategy to prevent the occurrence of acute inflammation.

Concanavalin A induces apoptosis in a dose-dependent manner by modulating thiol/disulfide homeostasis in C6 glioblastoma cells

Glioma is the most common brain tumor. C6 rat glioblastoma cells provide the possibility to the scientist to study brain cancer. Concanavalin A (Con A) has a lot of antitumoral effects, especially over oxidative stress. In the present study, it was aimed to decide the impacts of various doses of Con A on C6 glioblastoma cells regarding cytotoxicity, thiol/disulfide homeostasis, apoptosis, and inflammation. We detected the cytotoxic activity of Con A (from 7.8 to 500 µg/ml) in C6 cells by utilizing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and determined the toxic concentration of Con A. Once the optimal doses were found, the thiol-disulfide homeostasis, levels of total antioxidant and oxidant status (TAS and TOS), malondialdehyde (MDA) and glutathione (GSH), pro-inflammatory cytokines as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), apoptotic proteins as cytochrome c (CYCS), and caspase 3 (CASP3) were measured. Apoptotic and morphological changes in the C6 cells were examined with an inverted microscope and flow cytometry technique. Dose-dependent Con A triggered oxidative damage in the C6 cells, affecting the inflammatory pathway, so reducing proliferation with apoptotic proteins and morphological changes. But especially, Con A increased disulfide formation by disrupting the thiol/disulfide balance in C6 cells. This study revealed that Con A, known as carbohydrate-binding protein, generated oxidative damage, inflammation, and apoptosis in a dose-dependent manner by modulating thiol/disulfide homeostasis in C6 glioblastoma cells.

Summary of Natural Products Ameliorate Concanavalin A-Induced Liver Injury: Structures, Sources, Pharmacological Effects, and Mechanisms of Action

Liver diseases represent a threat to human health and are a significant cause of mortality and morbidity worldwide. Autoimmune hepatitis (AIH) is a progressive and chronic hepatic inflammatory disease, which may lead to severe complications. Concanavalin A (Con A)-induced hepatic injury is regarded as an appropriate experimental model for investigating the pathology and mechanisms involved in liver injury mediated by immune cells as well as T cell-related liver disease. Despite the advances in modern medicine, the only available strategies to treat AIH, include the use of steroids either solely or with immunosuppressant drugs. Unfortunately, this currently available treatment is associated with significant side-effects. Therefore, there is an urgent need for safe and effective drugs to replace and/or supplement those in current use. Natural products have been utilized for treating liver disorders and have become a promising therapy for various liver disorders. In this review, the natural compounds and herbal formulations as well as extracts and/or fractions with protection against liver injury caused by Con A and the underlying possible mechanism(s) of action are reviewed. A total of 53 compounds from different structural classes are discussed and over 97 references are cited. The goal of this review is to attract the interest of pharmacologists, natural product researchers, and synthetic chemists for discovering novel drug candidates for treating immune-mediated liver injury.

IL-33 ameliorates liver injury and inflammation in Poly I:C and Concanavalin-A induced acute hepatitis

The IL-33/ST2 axis is known to be involved in liver pathologies and IL-33 is over-expressed in mouse hepatitis models. We aimed to investigate the proposed protective effect of IL-33 in murine fulminant hepatitis induced by a Toll like receptor 3 (TLR3) viral mimetic, Poly I:C or by Concanavalin-A (ConA). The Balb/C mice were administered intravenously with ConA (15 mg/kg) or Poly I:C (30 μg/mouse) to induce acute hepatitis along with vehicle control. The recombinant mouse IL-33 (rIL-33) was injected (0.2 μg/mouse) to mice 2 h prior to ConA or Poly I:C injection to check its hepato-protective effects. The gross lesions, level of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), histopathology (H&E staining) and levels of IFNγ and TNFα were measured by ELISA. The gross pathological liver injury induced by Poly I:C or ConA was reduced by rIL-33 administration in mice. The levels of AST and ALT were significantly (P ≤ 0.05) higher in mice challenged with Poly I:C or ConA in comparison to control mice. The rIL-33 pre-treated mice in both Poly I:C and ConA challenge groups showed significantly (P ≤ 0.05) lower levels of AST and ALT, and decreased liver injury (parenchymal and per-vascular necrotic areas) in histological liver sections. The soluble levels of TNFα and IFNγ were significantly (P ≤ 0.05) raised in Poly I:C or ConA challenged mice than control mice. The levels of TNFα and IFNγ were significantly reduced (P ≤ 0.05) in rIL-33 pre-treated mice. In conclusion, the exogenous IL-33 administration mitigated liver injury and inflammation (decreased levels of IFNγ and TNFα) in Poly I:C and ConA-induced acute hepatitis in mice.

Sophocarpine attenuates septic liver injury through suppression of the NLRP3 inflammasome via autophagy-mediated degradation

Septic liver injury remains a challenge in sepsis treatment. Nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3 (NLRP3) inflammasome activation has been suggested to be a major cause of hepatocyte cell death in liver diseases. However, insufficient research has been performed to explore the underlying mechanisms associated with this. In the present study, sophocarpine, a pharmaceutical monomer originally isolated from Sophora flavescens, was suggested to attenuate septic liver injury in a mouse cecal ligation and puncture (CLP) model. By utilizing western blotting, ELISA, H&E staining and immunohistochemistry, the results demonstrated that sophocarpine treatment reversed CLP-induced elevations in serum aspartate transaminase, alanine transaminase, interleukin (IL)-6 and IL-1β levels. Additionally, sophocarpine appeared to have suppressed the activation of the NLRP3 inflammasome, as indicated by observed reductions in liver IL-1β, NLRP3, caspase 1-p20 and gasdermin D-p30 protein levels. Further investigation suggested that sophocarpine-induced autophagy was essential for this suppression of NLRP3 inflammasome activation, the inhibition of which reversed the protective effects of sophocarpine on CLP-induced liver injury. Collectively, results from the present study suggested a protective role for sophocarpine against septic liver injury, where sophocarpine may suppress NLRP3 inflammasome activation by autophagy-mediated degradation.

Nicotine attenuates concanavalin A-induced liver injury in mice by regulating the α7-nicotinic acetylcholine receptor in Kupffer cells

Nicotine, a potent parasympathomimetic alkaloid, manifests anti-inflammatory properties by activating nicotinic acetylcholine receptors (nAChRs). In this study, we evaluated the effects of nicotine on concanavalin A (ConA)-induced autoimmune hepatitis. Nicotine (0.5 and 1 mg/kg) was intraperitoneally administered to BALB/c mice and mice were intravenously injected with ConA (15 mg/kg) to induce hepatitis. The results showed that nicotine treatment ameliorated pathological lesions in livers and significantly suppressed the expression of pro-inflammatory cytokines in the livers. Such effects were mediated by inhibiting the nuclear factor-kappa B (NF-κB) signaling in livers. Interestingly, nicotine inhibited the ConA-induced inflammatory response in primary cultured Kupffer cells (KCs) but did not alter the proliferation of splenocytes. The protective effects of nicotine against ConA-induced hepatitis were abolished in KC-depleted mice, indicating the requirement of KCs in this process. Additionally, the expression of α7-nAChR on KCs was dramatically increased by nicotine treatment, and the protective effects of nicotine on ConA-induced liver injury were significantly suppressed by treatment with methyllycaconitine (MLA), a specific α7-nAChR antagonist. Consistently, in primary cultured KCs, the activation of NF-κB signaling was also regulated by nicotine treatment. This study suggests that nicotine increases α7-nAChR-mediated cholinergic activity in KCs resulting in decrease of ConA-induced autoimmune hepatitis through inhibiting NF-κB signaling.

Sophocarpine Suppresses NF-κB-Mediated Inflammation Both In Vitro and In Vivo and Inhibits Diabetic Cardiomyopathy

Diabetic cardiomyopathy (DCM) is a leading cause of mortality in patients with diabetes. DCM is a leading cause of mortality in patients with diabetes. We used both in vitro and in vivo experiments to investigate the hypothesis that sophocarpine (SPC), a natural quinolizidine alkaloid derived from a Chinese herb, could protect against DCM. We used hyperglycemic myocardial cells and a streptozotocin (STZ)-induced type 1 diabetes mellitus mouse model. SPC protected myocardial cells from hyperglycemia-induced injury by improving mitochondrial function, suppressing inflammation, and inhibiting cardiac apoptosis. The SPC treatment significantly inhibited the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling in high-glucose-stimulated inflammatory responses. Moreover, SPC significantly slowed the development and progression of DCM in STZ-induced diabetic mice. These results show that SPC suppresses NF-κB-mediated inflammation both in vitro and in vivo and may be used to treat DCM.

Supplementation of Plants with Immunomodulatory Properties during Pregnancy and Lactation-Maternal and Offspring Health Effects

A pregnant woman’s diet consists of many products, such as fruits, vegetables, cocoa, tea, chocolate, coffee, herbal and fruit teas, and various commercially available dietary supplements, which contain a high number of biological active plant-derived compounds. Generally, these compounds play beneficial roles in women’s health and the development of fetus health. There are, however, some authors who report that consuming excessive amounts of plants that contain high concentrations of polyphenols may negatively affect the development of the fetus and the offspring’s health. Important and problematic issues during pregnancy and lactation are bacterial infections treatment. In the treatment are proposals to use plant immunomodulators, which are generally considered safe for women and their offspring. Additional consumption of biologically active compounds from plants, however, may increase the risk of occurrences to irreversible changes in the offspring’s health. Therefore, it is necessary to carry out safety tests for immunomodulators before introducing them into a maternal diet. Here, we present data from animal experiments for the four most-studied plants immunomodulators genus: Rhodiola, Echinacea, Panax, and Camellia, which were used in maternal nutrition.

Hepatoprotective effect of capsaicin against concanavalin A-induced hepatic injury via inhibiting oxidative stress and inflammation

Immune-mediated liver injury plays a crucial role in the pathogenesis of liver diseases, which can result from viral infections, autoimmunity, alcohol intake, and drug use. Concanavalin A (Con A)-induced hepatitis is a well-characterized murine model with similar pathophysiology to that of human viral and autoimmune hepatitis. Capsaicin, a selective agonist of the transient potential vanilloid subfamily member 1 (TRPV1) receptor, exhibits anti-inflammatory effects on various causes of inflammation. In the present study, we investigated the effect of capsaicin on Con A-induced hepatitis. Capsaicin (1 mg/kg body weight) was administered by intraperitoneal injection, after which (30 minutes), the mice were challenged intravenously with Con A (20 μg/g body weight). We collected serum for plasma transaminase analysis. Pro-inflammatory cytokine levels and hepatocyte apoptosis were assayed by ELISA and TUNEL, respectively. Liver samples were collected for real-time PCR, hematoxylin and eosin staining, and measuring oxidative stress and myeloperoxidase levels. Activation of splenocytes and hepatic mononuclear cells was analyzed by flow cytometry. Compared with control, the capsaicin-treated group showed significantly decreased aminotransferase levels and markedly prolonged mouse survival. Capsaicin pretreatment also attenuated hepatocyte apoptosis and oxidative stress. Furthermore, tumor necrosis factor-α and interferon-γ levels in serum and liver were significantly suppressed, while the percentage of myeloid-derived suppressor cells increased after capsaicin pretreatment. Our findings indicate that capsaicin pretreatment protects mice from Con A-induced hepatic damage and is partially involved in inhibiting hepatocyte apoptosis, oxidative stress, and inflammatory mediators as well as regulating activation and recruitment of intrahepatic leukocytes.

3, 5, 3'-Triiodothyroacetic acid (TRIAC) is an anti-inflammatory drug that targets toll-like receptor 2

Drug repositioning is a strategy that explores new pharmaceutical applications of previously launched or failed drugs, and is advantageous since it saves capital and time. In this study, we examined the inhibition of TLR2 signaling by drug candidates. HEK-Blue™-hTLR2 cells were pretreated with drugs and stimulated using the TLR2 ligand, Pam3CSK4. Among the drugs that inhibited TLR2 signaling, we selected TRIAC, which is yet to be patented. Pretreatment with TRIAC decreased the TLR2 level and the phosphorylation of Akt and MAPKs in HEK-Blue™-hTLR2 cells. Since TLR2 is overexpressed in patients with acute hepatitis, we confirmed that TRIAC alleviates necrosis in a mouse model of Con A-induced acute hepatitis. The serum AST and ALT levels are indicators of liver damage, and are increased in Con A-induced hepatitis. Additionally, TLR2 and inflammatory cytokine levels are increased following administration of Con A and lead to liver damage. TRIAC decreased the serum levels of AST and ALT, and reduced liver tissue necrosis in mice with Con A-induced acute fulminant liver damage, by reducing the levels of inflammatory cytokines. In conclusion, TRIAC alleviates inflammation in mouse models of Con A-induced hepatitis by inhibiting the phosphorylation of Akt and MAPKs, the sub-mechanisms underlying TLR2 signaling.

IFN-γ-STAT1-iNOS Induces Myeloid Progenitors to Acquire Immunosuppressive Activity

Autoimmune diseases often induce dysregulated hematopoiesis with altered number and function of hematopoietic stem and progenitor cells (HSPCs). However, there are limited studies on the direct regulation of HSPCs on T cells, which are often detrimental to autoimmunity. Here, we found that in a murine model of Concanavalin A-induced autoimmune hepatitis, LSK (Lineage^-Sca-1⁺c-Kit⁺)-like cells accumulated in liver, spleen, and bone marrow (BM), which were myeloid progenitors (Lineage^-Sca-1^-c-Kit⁺) that upregulated Sca-1 expression upon T cell-derived IFN-γ stimulation. Strikingly, BM LSK-like cells from mice induced by Con A to develop autoimmune hepatitis or alternatively myeloid progenitors from wild-type mice possessed strong in vitro suppressive ability. Their suppressive function depended on T cell-derived IFN-γ in a paracrine fashion, which induced STAT1 phosphorylation, inducible nitric oxide synthase expression, and nitric oxide production. Blocking IFN-γ/IFN-γ receptor interaction, knockout of STAT1, or iNOS inhibition abrogated their suppressive function. In addition, the suppressive function was independent of differentiation; mitomycin C-treated myeloid progenitors maintained T cell suppressive ability in vitro. Our data demonstrate a mechanism of inflammation induced suppressive function of myeloid progenitors, which may participate directly in suppressing T cell-mediated immunopathology.