Si-Ni-San ameliorates chronic colitis by modulating type I interferons-mediated inflammation

Interferon-I modulation and natural products: Unraveling mechanisms and therapeutic potential in severe COVID-19

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to pose a significant global public health threat, particularly to older adults, pregnant women, and individuals with underlying chronic conditions. Dysregulated immune responses to SARS-CoV-2 infection are believed to contribute to the progression of COVID-19 in severe cases. Previous studies indicates that a deficiency in type I interferon (IFN-I) immunity accounts for approximately 15 %-20 % of patients with severe pneumonia caused by COVID-19, highlighting the potential therapeutic importance of modulating IFN-I signals. Natural products and their derivatives, due to their structural diversity and novel scaffolds, play a crucial role in drug discovery. Some of these natural products targeting IFN-I have demonstrated applications in infectious diseases and inflammatory conditions. However, the immunomodulatory potential of IFN-I in critical COVID-19 pneumonia and the natural compounds regulating the related signal pathway remain not fully understood. In this review, we offer a comprehensive assessment of the association between IFN-I and severe COVID-19, exploring its mechanisms and integrating information on natural compounds effective for IFN-I regulation. Focusing on the primary targets of IFN-I, we also summarize the regulatory mechanisms of natural products, their impact on IFNs, and their therapeutic roles in viral infections. Collectively, by synthesizing these findings, our goal is to provide a valuable reference for future research and to inspire innovative treatment strategies for COVID-19.

Anti-inflammatory and immunomodulatory effects of Glycyrrhiza uralensis fisch. On ulcerative colitis in rats: Role of nucleotide-binding oligomerization domain 2/receptor-interacting protein 2/nuclear factor-kappa B signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

As a traditional Chinese herb, Glycyrrhiza uralensis Fisch. exhibits a range of pharmacological activities, including anti-inflammatory, immunomodulatory and antifibrotic, which suggests its therapeutic potential for inflammatory bowel disease, and related mechanisms need to be further clarified.

AIM OF THE STUDY

To evaluate in vivo anti-inflammatory effects of Glycyrrhiza uralensis Fisch. aqueous extract (GE) on 2, 4, 6-trinitrobenzene sulfonic acid (TNBS)-induced acute experimental colitis rat model and its potential mechanisms.

MATERIALS AND METHODS

The protective effects of GE on IBD were evaluated in vivo using a TNBS and 75% ethanol-induced ulcerative colitis (UC) model. The evaluated clinical and anatomical indexes included body weight, colon length, disease activity index (DAI) score, Colonic Mucosal Damage Index (CMDI) score. The percentages of T, B lymphocytes, NK cells, and macrophages in the colon, spleen and peripheral blood were investigated by flow cytometry. Colon tissues were stained with Hematoxylin and Eosin (H&E) for histopathological examination. After using transcriptome sequencing to screen targeted genes, the expression of related genes was detected by Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR) and Western blot (WB).

RESULTS

The decrease of food intake, soft feces, and colon histopathological injury were observed in colitis rats, which were alleviated by GE, with the best therapeutic effect in the 100 mg/kg GE group. The average CMDI scores of colon in UC rats were decreased from 4.0 to 1.5. The percentages of CD161a+ NK cells, CD68+ total macrophages, CD68+/CD161a+ M1 type macrophages, CD3+ T lymphocytes, and CD45RA+ B lymphocytes were decreased in the spleen and colon. The transcriptomics analysis of colon showed that the results were mainly related to the TNF signaling pathway and NF-κB signaling pathway. The RT-qPCR and WB results determined that the upregulated expression of nucleotide-binding oligomerization domain 2 (NOD2), receptor-interacting protein 2 (RIP2), nuclear factor-kappa B (NF-κB), tumor necrosis factor-α (TNF-α) in the colon of the colitis rats were downregulated by GE treatment.

CONCLUSION

The research results indicate that GE can exert therapeutic effects on TNBS-induced UC in rats by alleviating cell injury and inflammatory responses, and its mechanisms may be related to the regulation of NOD2/RIP2/NF-κB signaling pathway.

Si-Ni-San ameliorates cholestatic liver injury by favoring P. goldsteinii colonization

ETHNOPHARMACOLOGICAL RELEVANCE

Current treatment options for cholestatic liver diseases are limited, and addressing impaired intestinal barrier has emerged as a promising therapeutic approach. Si-Ni-San (SNS) is a Traditional Chinese Medicine (TCM) formula commonly utilized in the management of chronic liver diseases. Our previous studies have indicated that SNS effectively enhanced intestinal barrier function through the modulation of gut microbiota.

AIM OF THE STUDY

This study aims to verify the therapeutic effects of SNS on cholestatic liver injury, focusing on elucidating the underlying mechanism involving the gut-liver axis.

MATERIALS AND METHODS

The 16s RNA gene sequencing, non-targeted metabolomics were used to investigate the effects of SNS on the gut microbiota dysbiosis. Fecal microbiota transplantation (FMT) was conducted to identify potential beneficial probiotics underlying the therapeutic effects of SNS.

RESULTS

Our results demonstrated that SNS significantly ameliorated cholestatic liver injury induced by partial bile duct ligation (pBDL). Additionally, SNS effectively suppressed cholestasis-induced inflammation and barrier dysfunction in both the small intestine and colon. While SNS did not impact the intestinal FXR-FGF15-hepatic CYP7A1 axis, it notably improved gut microbiota dysbiosis and modulated the profile of microbial metabolites, including beneficial secondary bile acids and tryptophan derivatives. Furthermore, gut microbiota depletion experiments and FMT confirmed that the therapeutic benefits of SNS in cholestatic liver disease are dependent on gut microbiota modulation, particularly through the promotion of the growth of potential probiotic P. goldsteinii. Moreover, a synergistic improvement in cholestatic liver injury was observed with the co-administration of P. goldsteinii and SNS.

CONCLUSION

Our study underscores that SNS effectively alleviates cholestatic liver injury by addressing gut microbiota dysbiosis and enhancing intestinal barrier function, supporting its rational clinical utilization. Furthermore, we highlight P. goldsteinii as a promising probiotic candidate for the management of cholestatic liver diseases.

Si-Ni-San alleviates intestinal and liver damage in ulcerative colitis mice by regulating cholesterol metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Si-Ni-San (SNS), a traditional Chinese medicinal formula derived from Treatise on Febrile Diseases, is considered effective in the treatment of inflammatory bowel diseases based upon thousands of years of clinical practice. However, the bioactive ingredients and underlying mechanisms are still unclear and need further investigation.

AIM OF THE STUDY

This study aimed to evaluate the effect, explore the bioactive ingredients and the underlying mechanisms of SNS in ameliorating ulcerative colitis (UC) and associated liver injury in dextran sodium sulphate (DSS)-induced mouse colitis models.

MATERIALS AND METHODS

The effect of SNS (1.5, 3, 6 g/kg) on 3% DSS-induced acute murine colitis was evaluated by disease activity index (DAI), colon length, inflammatory cytokines, hematoxylin-eosin (H&E) staining, tight junction proteins expression, ALT, AST, and oxidative stress indicators. HPLC-ESI-IT/TOF MS was used to analyze the chemical components of SNS and the main xenobiotics in the colon of UC mice after oral administration of SNS. Network pharmacological study was then conducted based on the main xenobiotics. Flow cytometry and immunohistochemistry techniques were used to demonstrate the inhibitory effect of SNS on Th17 cells differentiation and the amelioration of Th17/Treg cell imbalance. LC-MS/MS, Real-time quantitative polymerase chain reaction (RT-qPCR), and western blotting techniques were performed to investigate the oxysterol-Liver X receptor (LXRs) signaling activity in colon. Targeted bile acids metabolomics was conducted to reveal the change of the two major pathways of bile acid synthesis in the liver, and the expression of key metabolic enzymes of bile acids synthesis was characterized by RT-qPCR and western blotting techniques.

RESULTS

SNS (1.5, 3, 6 g/kg) decreased the DAI scores, protected intestinal mucosa barrier, suppressed the production of pro-inflammatory cytokines, improved hepatic and splenic enlargement and alleviated liver injury in a dose-dependent manner. A total of 22 components were identified in the colon of SNS (6 g/kg) treated colitis mice, and the top 10 components ranked by relative content were regarded as the potential effective chemical components of SNS, and used to conduct network pharmacology research. The efficacy of SNS was mediated by a reduction of Th17 cell differentiation, restoration of Th17/Treg cell homeostasis in the colon and spleen, and the experimental results were consistent with our hypothesis and the biological mechanism predicted by network pharmacology. Mechanistically, SNS regulated the concentration of 25-OHC and 27-OHC by up-regulated CH25H, CYP27A1 protein expression in colon, thus affected the expression and activity of LXR, ultimately impacted Th17 differentiation and Th17/Treg balance. It was also found that SNS repressed the increase of hepatic cholesterol and reversed the shift of BA synthesis to the acidic pathway in UC mice, which decreased the proportion of non-12-OH BAs in total bile acids (TBAs) and further ameliorated colitis and concomitant liver injury.

CONCLUSIONS

This study set the stage for considering SNS as a multi-organ benefited anti-colitis prescription based on the significant effect of ameliorating intestinal and liver damage, and revealed that derivatives of cholesterol, namely oxysterols and bile acids, were closely involved in the mechanism of SNS anti-colitis effect.

Network pharmacology- and molecular docking-based investigation on the mechanism of action of Si-ni San in the treatment of depression combined with anxiety and experimental verification in adolescent rats

Background

The incidence rate of adolescent depression and anxiety has been increasing since the outbreak of COVID-19, which there are no effective therapeutic drugs available. Si-ni San is commonly used in traditional Chinese medicine for the treatment of depression-like as well as anxiety-like behavior, but its mechanism for treating depression combined with anxiety during adolescence is not yet clear.

Methods

Network pharmacology was used to explore potential drug molecules and related targets, molecular docking and molecular dynamics (MD) simulation were used to evaluate the interaction between the potential drug molecules and related targets, and a model of anxiety combined with depression in adolescent rats as well as the following behavioral tests and molecular biology tests were used to verify the results from network pharmacology and molecular docking.

Results

As a result, 256 active ingredients of Si-ni San and 1128 potential targets were screened out. Among them, quercetin, Luteolin, kaempferol, 7-Methoxy-2-methyl isoflavone, formononetin showed to be the most potential ingredients; while STAT3, IL6, TNF, AKT1, AKT1, TP53, IL1B, MAPK3, VEGFA, CASP3, MMP9 showed to be the most potential targets. AGE-RAGE signaling pathway in diabetic complications, IL-17 signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway and TNF signaling pathway, which are involved in anti-inflammation processes, showed to be the most probable pathways regulated by Si-ni San. Molecular docking and MD simulation between the compounds to inflammation-associated targets revealed good binding abilities of quercetin, Luteolin, kaempferol, nobiletin and formononetin to PTGS2 and PPARγ. In the experiment with adolescent rats, Si-ni San markedly suppressed early maternal separation (MS) combined with adolescent chronic unpredictable mild stress (CUMS)-induced depression combined with anxiety. The qPCR results further indicated that Si-ni San regulated the oxidative stress and inflammatory response.

Conclusion

This study demonstrates that adolescent anxiety- and depression-like behavior induced by MS combined CUMS can be ameliorated by Si-ni San by improved inflammation in hippocampus via targeting TNF pathway and Nrf2 pathway, helping to reveal the mechanism of Si-ni San in treating adolescent depression combined with anxiety.

TBK1 is paradoxical in tumor development: a focus on the pathway mediating IFN-I expression

TANK-binding kinase 1 (TBK1) is a member of the IKK family and plays a crucial role in the activation of non-canonical NF-κB signaling and type I interferon responses. The aberrant activation of TBK1 contributes to the proliferation and survival of various types of tumor cells, particularly in specific mutational or tumorous contexts. Inhibitors targeting TBK1 are under development and application in both in vivo and in vitro settings, yet their clinical efficacy remains limited. Numerous literatures have shown that TBK1 can exhibit both tumor promoting and tumor inhibiting effects. TBK1 acts as a pivotal node within the innate immune pathway, mediating anti-tumor immunity through the activation of innate immune responses. Facilitating interferon-I (IFN-I) production represents a critical mechanism through which TBK1 bridges these processes. IFN has been shown to exert both beneficial and detrimental effects on tumor progression. Hence, the paradoxical role of TBK1 in tumor development may necessitate acknowledgment in light of its downstream IFN-I signaling cascade. In this paper, we review the signaling pathways mediated by TBK1 in various tumor contexts and summarize the dual roles of TBK1 and the TBK1-IFN pathways in both promoting and inhibiting tumor progression. Additionally, we highlight the significance of the TBK1-IFN pathway in clinical therapy, particularly in the context of immune response. We anticipate further advancements in the development of TBK1 inhibitors as part of novel cancer treatment strategies.

The role of cGAS in epithelial dysregulation in inflammatory bowel disease and gastrointestinal malignancies

The gastrointestinal tract is lined by an epithelial monolayer responsible for selective permeability and absorption, as well as protection against harmful luminal contents. Recognition of foreign or aberrant DNA within these epithelial cells is, in part, regulated by pattern recognition receptors such as cyclic GMP-AMP synthase (cGAS). cGAS binds double-stranded DNA from exogenous and endogenous sources, resulting in the activation of stimulator of interferon genes (STING) and a type 1 interferon response. cGAS is also implicated in non-canonical pathways involving the suppression of DNA repair and the upregulation of autophagy via interactions with PARP1 and Beclin-1, respectively. The importance of cGAS activation in the development and progression of inflammatory bowel disease and gastrointestinal cancers has been and continues to be explored. This review delves into the intricacies of the complex role of cGAS in intestinal epithelial inflammation and gastrointestinal malignancies, as well as recent therapeutic advances targeting cGAS pathways.

The dual function of cGAS-STING signaling axis in liver diseases

Numerous liver diseases, such as nonalcoholic fatty liver disease, hepatitis, hepatocellular carcinoma, and hepatic ischemia-reperfusion injury, have been increasingly prevalent, posing significant threats to global health. In recent decades, there has been increasing evidence linking the dysregulation of cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING)-related immune signaling to liver disorders. Both hyperactivation and deletion of STING can disrupt the immune microenvironment dysfunction, exacerbating liver disorders. Consequently, there has been a surge in research investigating medical agents or mediators targeting cGAS-STING signaling. Interestingly, therapeutic manipulation of the cGAS-STING pathway has yielded inconsistent and even contradictory effects on different liver diseases due to the distinct physiological characteristics of intrahepatic cells that express and respond to STING. In this review, we comprehensively summarize recent advancements in understanding the dual roles of the STING pathway, highlighting that the benefits of targeting STING signaling depend on the specific types of target cells and stages of liver injury. Additionally, we offer a novel perspective on the suitability of STING agonists and antagonists for clinical assessment. In conclusion, STING signaling remains a highly promising therapeutic target, and the development of STING pathway modulators holds great potential for the treatment of liver diseases.

Novel applications of Yinhua Miyanling tablets in ulcerative colitis treatment based on metabolomics and network pharmacology

BACKGROUND

Yinhua Miyanling tablets (YMT), comprising 10 Chinese medicinal compounds, is a proprietary Chinese medicine used in the clinical treatment of urinary tract infections. Medicinal compounds, extracts, or certain monomeric components in YMT all show good effect on ulcerative colitis (UC). However, no evidence supporting YMT as a whole prescription for UC treatment is available.

PURPOSE

To evaluate the anti-UC activity of YMT and elucidate the underlying mechanisms. The objective of the study was to provide evidence for the add-on development of YMT to treat UC.

METHODS

First, YMT's protective effect on the intestinal barrier was evaluated using a lipopolysaccharide (LPS)-induced Caco-2 intestinal injury model. Second, the UC mouse model was established using dextran sodium sulfate (DSS) to determine YMT's influence on symptoms, inflammatory factors, intestinal barrier, and histopathological changes in the colon. Third, an integrated method combining metabolomics and network pharmacology was employed to screen core targets and key metabolic pathways with crucial roles in YMT's therapeutic effect on UC. Molecular docking was employed to identify the key targets with high affinity. Finally, western blotting was performed to validate the mechanism of YMT action against UC.

RESULTS

YMT enhanced the transepithelial electrical resistance value and improved the expression of proteins of the tight junctions dose-dependently in LPS-induced Caco-2 cells. UC mice treated with YMT exhibited alleviated pathological lesions of the colon tissue in the in vivo pharmacodynamic experiments. The colonic lengths tended to be normal, and the levels of inflammatory factors (TNF-α, IL-6, and iNOS) along with those of the core enzymes (MPO, MDA, and SOD) improved. YMT effectively ameliorated DSS-induced colonic mucosal injury; pathological changes along with ultrastructure damage were significantly alleviated (evidenced by a relatively intact colon tissue, recovery of epithelial damage, repaired gland, reduced infiltration of inflammatory cells and epithelial cells arranged closely with dense microvilli). Seven key targets (IL-6, TNF-α, MPO, COX-2, HK2, TPH, and CYP1A2) and four key metabolic pathways (arachidonic acid metabolism, linoleate metabolism, glycolysis, and gluconeogenesis and tyrosine biosynthesis) were identified to play vital roles in the treatment on UC using YMT.

CONCLUSIONS

YMT exerts beneficial therapeutic effects on UC by regulating multiple endogenous metabolites, targets, and metabolic pathways, suggestive of its potential novel application in UC treatment.

Si-Ni-San promotes liver regeneration by maintaining hepatic oxidative equilibrium and glucose/lipid metabolism homeostasis

ETHNOPHARMACOLOGICAL RELEVANCE

The efficacy of clinical treatments for various liver diseases is intricately tied to the liver's regenerative capacity. Insufficient or failed liver regeneration is a direct cause of mortality following fulminant hepatic failure and extensive hepatectomy. Si-Ni-San (SNS), a renowned traditional Chinese medicine prescription for harmonizing liver and spleen functions, has shown clinical efficacy in the alleviation of liver injury for thousands of years. However, the precise molecular pharmacological mechanisms underlying its effects remain unclear.

AIMS OF THE STUDY

This study aimed to investigate the effects of SNS on liver regeneration and elucidate the underlying mechanisms.

MATERIALS AND METHODS

A mouse model of 70% partial hepatectomy (PHx) was used to analyze the effects of SNS on liver regeneration. Aquaporin-9 knockout mice (AQP9-/-) were used to demonstrate that SNS-mediated enhancement of liver regeneration was AQP9-targeted. A tandem dimer-Tomato-tagged AQP9 transgenic mouse line (AQP9-RFP) was utilized to determine the expression pattern of AQP9 protein in hepatocytes. Immunoblotting, quantitative real-time PCR, staining techniques, and biochemical assays were used to further explore the underlying mechanisms of SNS.

RESULTS

SNS treatment significantly enhanced liver regeneration and increased AQP9 protein expression in hepatocytes of wild-type mice (AQP9+/+) post 70% PHx, but had no significant effects on AQP9-/- mice. Following 70% PHx, SNS helped maintain hepatic oxidative equilibrium by increasing the levels of reactive oxygen species scavengers glutathione and superoxide dismutase and reducing the levels of oxidative stress molecules H2O2 and malondialdehyde in liver tissues, thereby preserving this crucial process for hepatocyte proliferation. Simultaneously, SNS augmented glycerol uptake by hepatocytes, stimulated gluconeogenesis, and maintained glucose/lipid metabolism homeostasis, ensuring the energy supply required for liver regeneration.

CONCLUSIONS

This study provides the first evidence that SNS maintains liver oxidative equilibrium and glucose/lipid metabolism homeostasis by upregulating AQP9 expression in hepatocytes, thereby promoting liver regeneration. These findings offer novel insights into the molecular pharmacological mechanisms of SNS in promoting liver regeneration and provide guidance for its clinical application and optimization in liver disease treatment.

Dual-channel hypergraph convolutional network for predicting herb-disease associations

Herbs applicability in disease treatment has been verified through experiences over thousands of years. The understanding of herb-disease associations (HDAs) is yet far from complete due to the complicated mechanism inherent in multi-target and multi-component (MTMC) botanical therapeutics. Most of the existing prediction models fail to incorporate the MTMC mechanism. To overcome this problem, we propose a novel dual-channel hypergraph convolutional network, namely HGHDA, for HDA prediction. Technically, HGHDA first adopts an autoencoder to project components and target protein onto a low-dimensional latent space so as to obtain their embeddings by preserving similarity characteristics in their original feature spaces. To model the high-order relations between herbs and their components, we design a channel in HGHDA to encode a hypergraph that describes the high-order patterns of herb-component relations via hypergraph convolution. The other channel in HGHDA is also established in the same way to model the high-order relations between diseases and target proteins. The embeddings of drugs and diseases are then aggregated through our dual-channel network to obtain the prediction results with a scoring function. To evaluate the performance of HGHDA, a series of extensive experiments have been conducted on two benchmark datasets, and the results demonstrate the superiority of HGHDA over the state-of-the-art algorithms proposed for HDA prediction. Besides, our case study on Chuan Xiong and Astragalus membranaceus is a strong indicator to verify the effectiveness of HGHDA, as seven and eight out of the top 10 diseases predicted by HGHDA for Chuan-Xiong and Astragalus-membranaceus, respectively, have been reported in literature.

Si-Ni-San inhibits hepatic Fasn expression and lipid accumulation in MAFLD mice through AMPK/p300/SREBP-1c axis

BACKGROUND

Soothing the liver and regulating qi is one of the core ideas of traditional Chinese medicine (TCM) in the treatment of fatty liver. Si-Ni-San (SNS) is a well-known herbal formula in TCM for liver soothing and qi regulation in fatty liver treatment. However, its efficacy lacks modern scientific evidence.

PURPOSE

This study was aimed to investigate the impact of SNS on metabolic associated fatty liver disease (MAFLD) in mice and explore the underlying molecular mechanisms, particularly its effects on lipid metabolism in hepatocytes.

METHODS

The therapeutic effect of SNS was evaluated using in vivo and in vitro models of high-fat/high-cholesterol (HFHC) diet-induced mice and palmitic acid (PA)-induced hepatocytes, respectively. Molecular biological techniques such as RNA-sequencing (RNA-seq), co-immunoprecipitation (co-IP), and western blotting were employed to elucidate the molecular mechanism of SNS in regulating lipid metabolism in hepatocytes.

RESULTS

Our findings revealed that SNS effectively reduced lipid accumulation in the livers of HFHC diet-induced mice and PA-induced hepatocytes. RNA-seq analysis demonstrated that SNS significantly down-regulated the expression of fatty acid synthase (Fasn) in the livers of HFHC-fed mice. Mechanistically, SNS inhibited Fasn expression and lipid accumulation by activating adenosine monophosphate (AMP)-activated protein kinase (AMPK). Activation of AMPK suppressed the activity of the transcriptional coactivator p300 and modulated the protein stability of sterol regulatory element-binding protein-1c (SREBP-1c). Importantly, p300 was required for the inhibition of Fasn expression and lipid accumulation by SNS. Furthermore, SNS activated AMPK by decreasing adenosine triphosphate (ATP) production in hepatocytes.

CONCLUSION

This study provided novel evidence on the regulatory mechanisms underlying the effects of SNS on Fasn expression. Our findings demonstrate, for the first time, that SNS exerts suppressive effects on Fasn expression through modulation of the AMPK/p300/SREBP-1c axis. Consequently, this regulatory pathway mitigates excessive lipid accumulation and ameliorates MAFLD in mice.

Sinisan ameliorates colonic injury induced by water immersion restraint stress by enhancing intestinal barrier function and the gut microbiota structure

CONTEXT

Sinisan (SNS) has been used to treat psychosomatic diseases of the digestive system. But little is known about how SNS affects water immersion restraint stress (WIRS).

OBJECTIVE

To study the effects of SNS on colonic tissue injury in the WIRS model.

MATERIALS AND METHODS

Forty-eight Kunming (KM) mice were randomized into 6 groups (n = 8): The control and WIRS groups receiving deionized water; the SNS low-dose (SL, 3.12 g/kg/d), SNS middle-dose (SM, 6.24 g/kg/d), SNS high-dose (SH, 12.48 g/kg/d), and diazepam (DZ, 5 mg/kg/d) groups; each with two daily administrations for 5 consecutive days. The 5 treatment groups were subjected to WIRS for 24 h on day 6. The effects of SNS on colon tissue injury caused by WIRS were assessed by changes in colon histology, inflammatory cytokines, brain-gut peptides, and tight junction (TJ) proteins levels. 16S rRNA gene sequencing was used to detect the regulation of the gut microbiota.

RESULTS

SNS pretreatment significantly reduced TNF-α (0.75- to 0.81-fold), IL-6 (0.77-fold), and IFN-γ (0.69-fold) levels; and increased TJ proteins levels, such as ZO-1 (4.06- to 5.27-fold), claudin-1 (3.33- to 5.14-fold), and occludin (6.46- to 11.82-fold). However, there was no significant difference between the levels of substance P (SP) and vasoactive intestinal peptide (VIP) in the control and WIRS groups. SNS regulated the composition of gut microbiota in WIRS mice.

CONCLUSION

The positive effects of SNS on WIRS could provide a theoretical basis to treat stress-related gastrointestinal disorders.

cGAS-STING signaling pathway in intestinal homeostasis and diseases

The intestinal mucosa is constantly exposed to commensal microbes, opportunistic pathogens, toxins, luminal components and other environmental stimuli. The intestinal mucosa consists of multiple differentiated cellular and extracellular components that form a critical barrier, but is also equipped for efficient absorption of nutrients. Combination of genetic susceptibility and environmental factors are known as critical components involved in the pathogenesis of intestinal diseases. The innate immune system plays a critical role in the recognition and elimination of potential threats by detecting pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). This host defense is facilitated by pattern recognition receptors (PRRs), in which the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway has gained attention due to its role in sensing host and foreign double-stranded DNA (dsDNA) as well as cyclic dinucleotides (CDNs) produced by bacteria. Upon binding with dsDNA, cGAS converts ATP and GTP to cyclic GMP-AMP (cGAMP), which binds to STING and activates TANK binding kinase 1 (TBK1) and interferon regulatory factor 3 (IRF3), inducing type I interferon (IFN) and nuclear factor kappa B (NF-κB)-mediated pro-inflammatory cytokines, which have diverse effects on innate and adaptive immune cells and intestinal epithelial cells (IECs). However, opposite perspectives exist regarding the role of the cGAS-STING pathway in different intestinal diseases. Activation of cGAS-STING signaling is associated with worse clinical outcomes in inflammation-associated diseases, while it also plays a critical role in protection against tumorigenesis and certain infections. Therefore, understanding the context-dependent mechanisms of the cGAS-STING pathway in the physiopathology of the intestinal mucosa is crucial for developing therapeutic strategies targeting the cGAS-STING pathway. This review aims to provide insight into recent findings of the protective and detrimental roles of the cGAS-STING pathway in intestinal diseases.

Si-Ni-San improves experimental colitis by favoring Akkermensia colonization

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is widely believed to be a leading risk factor of colorectal cancer. Gut microbiota is a known vital player in the progression of UC. Si-Ni-San (SNS) has been considered to effectively treat colitis in clinical practice during thousands of years, yet whether SNS ameliorated acute colitis mouse model by modulating intestinal flora has not been distinctly elucidated.

AIM OF THE STUDY

Our study aimed to elucidate the effect of SNS against acute murine colitis and focused on the underlying mechanisms of SNS targeting gut microbiota.

MATERIALS AND METHODS

16S RNA sequencing, molecular biological analysis, and fecal microbiota transplants (FMT) were conducted to reveal the mechanisms of SNS in regulating gut microbiota.

RESULTS

In our study, SNS dramatically inhibited DSS-induced acute inflammatory responses by improving gut microbiota dysbiosis, as evidenced by decreased abundance proinflammatory species, upregulated abundance of anti-inflammatory species and potentially altered microbiota metabolite metabolism. Additionally, intestinal flora knockout and FMT experiments confirmed that the therapeutic effect of SNS on colitis was dependent on gut microbiota, and specifically on favoring the growth of potential probiotics, Akkermansia genus. Furthermore, we found that SNS alone and SNS combined with Akkermansia muciniphila (A. muciniphila) increased Mucin 2 (MUC2) production, thus enhancing the competitive edge of A. muciniphila among pathogenic gut microbiota.

CONCLUSION

Our study shed lights on the underlying mechanism of SNS in attenuating acute murine colitis from the perspective of intestinal flora and provides novel insights into the discovery of adjacent therapeutic strategy against colitis based on SNS and probiotics.

CLASSIFICATION

Gastro-intestinal system.

Saikosaponins ameliorate hyperlipidemia in rats by enhancing hepatic lipid and cholesterol metabolism

ETHNOPHARMACOLOGICAL RELEVANCE

Hyperlipidemia is the systemic manifestation of abnormal lipid metabolism, characterized by elevated circulating levels of cholesterol and triglyceride and a high risk of cardiovascular events. Radix Bupleuri (RB) is a traditional Chinese herbal product used to treat liver diseases. Our previous study demonstrated that Saikosaponins (SSs), the most potent bioactive ingredients in RB, ameliorate hepatic steatosis. However, whether SSs have anti-hyperlipidemia effects and plausible underlying mechanisms remain elusive.

AIM OF THE STUDY

To comprehensively evaluate the lipid-lowering potential of SSs against hyperlipidemia in rats.

MATERIALS AND METHODS

RNA sequencing and untargeted metabolomics approaches were applied to analyze the changes in the liver transcriptome and serum lipid profile in long-term high-fat diet feeding-induced hyperlipidemia rats in response to SSs or positive drug simvastatin (SIM) intervention.

RESULTS

Our data revealed that SSs significantly alleviated HFD-induced hypertriglyceridemia and hypercholesterolemia. Combined with the analysis of gene ontology enrichment analysis and gene set enrichment analysis, we found that SSs remarkably repaired the unbalanced blood lipid metabolic spectrum in a dose-dependent manner by increasing the hepatic uptake of circulating fatty acids and facilitating mitochondrial respiration in fatty acid oxidation, comparable to SIM group. In addition, SSs markedly modulated cholesterol clearance by promoting intracellular cholesterol efflux, HDL remodeling, LDL particle clearance, and bile acid synthesis. SSs also efficiently protected the liver from lipid overload-related oxidative stress and lipid peroxidation, as well as substantially exaggerated inflammatory response.

CONCLUSION

Our research not only unraveled the intricate mechanisms underlying the lipid-lowering functions of SSs but also provided novel perspectives on developing an SSs-based therapeutic strategy for the treatment of hyperlipidemia.

CLASSIFICATION

Metabolism.

Total glucosides of paeony alleviates scleroderma by inhibiting type I interferon responses

ETHNOPHARMACOLOGICAL RELEVANCE

Type I interferon (IFN) is believed to play a pathogenic role in systemic sclerosis (SSc, also called scleroderma), which is an autoimmune rheumatic disease. Our previous studies have found that Chinese medicine formula Si-Ni-San (SNS, composed of Glycyrrhiza uralensis Fisch., Bupleurum chinense DC., Paeonia lactiflora Pall., and Citrus aurantium L.) had inhibitory effects on type I IFN responses. Among these herbal products, Paeonia lactiflora Pall. has been traditionally used to treat inflammation-related diseases, yet its therapeutic effects against type I IFN-related diseases and potential bioactive ingredients are not characterized.

AIM OF THE STUDY

We aim to identify bioactive ingredient with anti-type I IFN activity from herbal products in SNS and further elucidate its therapeutic effect against scleroderma and underlying mechanisms.

MATERIALS AND METHODS

We constructed a Gaussia-luciferase (Gluc) reporter assay system to identify ingredients with anti-type I IFN activities from SNS. In RAW264.7 cells, real-time PCR (RT-PCR) and western blotting were used to investigate the induction of type I IFN pathway. Additionally, in a bleomycin (BLM)-induced experimental scleroderma model, the expression of fibrotic genes, type I IFN-related genes, inflammatory cytokines, and cytotoxic granules were measured by RT-PCR, and the histopathological changes were determined by H&E staining, Masson's staining and immunohistochemistry analysis.

RESULTS

Our data demonstrated that total glucosides of paeony (TGP) was the bioactive component of SNS that selectively inhibited TLR3-mediated type I IFN responses and blocked type I IFN-induced downstream JAK-STAT signaling pathways. In the BLM-induced scleroderma mouse model, TGP ameliorated skin fibrosis by inhibiting multiple targets in the upstream and downstream of type I IFN signaling. Further research found that TGP hindered polarization of M2 macrophages and their profibrotic effects and reduced cytotoxic T lymphocytes and their cytotoxic granules by suppressing Cxcl9 and Cxcl10 in the skin tissue of scleroderma mice.

CONCLUSIONS

Our study not only sheds novel lights into the immunoregulative effects of TGP but also provides convincing evidence to develop TGP-based therapies in the treatment of scleroderma and other autoimmune diseases associated with type I IFN signatures.

CLASSIFICATION

Skin.

Si-Ni-SAN ameliorates obesity through AKT/AMPK/HSL pathway-mediated lipolysis: Network pharmacology and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Si-Ni-San (SNS) is a famous Chinese herbal formula used in China for thousands of years. It has clinical effects on a variety of lipid metabolism disorders, but the ameliorating effects of SNS on obesity and underlying mechanisms remained poorly elucidated.

AIM OF THE STUDY

This study aims to explore the therapeutic effect and mechanism of SNS on obesity from multiple perspectives in vitro and in vivo.

MATERIALS AND METHODS

The high-fat diet (HFD)-induced obesity mouse model was established to evaluate the effect of SNS. Then network pharmacologic methods were performed to predict underlying mechanisms, and the core pathways were verified in animal and cell studies.

RESULTS

Our results demonstrated that SNS significantly reduced body weight, body fat content, white adipose tissue (WAT) expansion in obese mice, and lipid accumulation in primary mouse embryonic fibroblasts (MEFs) cells. Network pharmacologic analysis identified 66 potential therapeutic targets, and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of these genes revealed that the most important signaling pathway includes AMP-activated protein kinase (AMPK) signaling pathway, regulation of lipolysis in adipocytes, lipid and atherosclerosis. Western blot assay confirmed that SNS activated hormone-sensitive triglyceride lipase (HSL) and adipose triglyceride lipase (ATGL) activity and promoted lipolysis through AMPK signaling pathway.

CONCLUSION

The results confirmed that SNS improves lipid accumulation through AKT/AMPK/HSL axis mediated lipolysis, which opens a new option for clinical treatment of obesity and associated complications.

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.

Sinisan alleviates depression-like behaviors by regulating mitochondrial function and synaptic plasticity in maternal separation rats

BACKGROUND

Sinisan (SNS) consists of four kinds of herbs, which is the core of antidepressant prescription widely used in traditional Chinese medicine clinic treatment for depression induced by early life stress. However, the role and precise mechanism of SNS antidepressant have not yet been elucidated.

PURPOSE

This study aimed to investigate the mechanism SNS on antidepressant of regulating mitochondrial function to improve hippocampal synaptic plasticity.

METHODS

90 Sprague-Dawley (SD) rats male pups on Post-Natal Day (PND) 0 were randomly divided into Control group (ddH₂0), Model group (ddH₂0), Fluoxetine group (5.0 mg/kg fluoxetine), and SNS-L group (2.5 g/kg SNS), SNS-M group (5.0 g/kg SNS) and SNS-H group (10.0 g/kg SNS), 15 animals per group. Maternal separation (MS) from PND1 to PND21, drug intervention from PND60 to PND90, and behavior tests including sucrose preference test, open field test and forced swimming test from PND83 to PND90 were performed. Synaptic structure and mitochondrial structure were observed by TEM. The expression levels of PSD-95 and SYN were detected by immunohistochemistry and western blot test, the adenosine triphosphate (ATP) content in the hippocampus was detected by assay kits, and the expression levels of Mfn2, Drp1 and Fis1 protein were detected by western bolt test.

RESULTS

SNS can alleviate depression-like and anxiety-like behaviors in MS rats, improve the damage of synapses and mitochondria, reduce the decrease of ATP in hippocampus, and reverse the expression levels of PSD-95, SYN, Mfn2, Drp1, and Fis1 proteins.

CONCLUSION

SNS reduced the risk of early life stress induced depression disorder via regulating mitochondrial function and synaptic plasticity. Targeting mitochondrial may be a novel prospective therapeutic avenue for antidepressant.

Perspectives of herbs and their natural compounds, and herb formulas on treating diverse diseases through regulating complicated JAK/STAT signaling

JAK/STAT signaling pathways are closely associated with multiple biological processes involved in cell proliferation, apoptosis, inflammation, differentiation, immune response, and epigenetics. Abnormal activation of the STAT pathway can contribute to disease progressions under various conditions. Moreover, tofacitinib and baricitinib as the JAK/STAT inhibitors have been recently approved by the FDA for rheumatology disease treatment. Therefore, influences on the STAT signaling pathway have potential and perspective approaches for diverse diseases. Chinese herbs in traditional Chinese medicine (TCM), which are widespread throughout China, are the gold resources of China and have been extensively used for treating multiple diseases for thousands of years. However, Chinese herbs and herb formulas are characterized by complicated components, resulting in various targets and pathways in treating diseases, which limits their approval and applications. With the development of chemistry and pharmacology, active ingredients of TCM and herbs and underlying mechanisms have been further identified and confirmed by pharmacists and chemists, which improved, to some extent, awkward limitations, approval, and applications regarding TCM and herbs. In this review, we summarized various herbs, herb formulas, natural compounds, and phytochemicals isolated from herbs that have the potential for regulating multiple biological processes via modulation of the JAK/STAT signaling pathway based on the published work. Our study will provide support for revealing TCM, their active compounds that treat diseases, and the underlying mechanism, further improving the rapid spread of TCM to the world.

Shouhui Tongbian Capsule ameliorates constipation via gut microbiota-5-HT-intestinal motility axis

Constipation has become an epidemic enteric medical problem, accompanied with increasing long-term sequelae. Gut microbiota and serotonin (5-HT) have been believed as predominant player in the treatment of constipation. In clinical practices, Shouhui Tongbian Capsule (SHTB) was found to effectively improve constipation symptoms and promote gastrointestinal motility. However, the specific mechanism of SHTB is not clearly elucidated. Our current study aims to explore the therapeutic effects of SHTB against the development of constipation and the underlying mechanisms related to gut bacterial and 5-HT. We established loperamide hydrochloride (LH)-induced experimental constipation mouse model to evaluate the effect of SHTB. 16S RNA sequencing, fecal microbiota transplants (FMT), high performance liquid chromatograph, and molecular biological analysis were performed to investigate the potential mechanisms of SHTB. Our data demonstrated that SHTB significantly ameliorated LH-induced experimental constipation and accelerated enteric motility via promoting 5-HT biosynthesis in enterochromaffin cells and enteric neuron growth of the enteric nervous system (ENS) in both the small intestine and colon. Additionally, SHTB significantly modulated gut microbiota dysbiosis and potentially altered microbiota metabolites to enhance intestinal 5-HT production. Finally, FMT study confirmed that the effects of SHTB on 5-HT production and constipation are dependent on modulating intestinal microbiota dysbiosis. In conclusion, our current study deciphered therapeutic mechanism of SHTB in the treatment of experimental constipation from perspectives of gut microbiota-5-HT-intetinal motility axis and provides novel insights into the appropriate and safe application of SHTB in the clinic.

Atractylenolide-1 targets SPHK1 and B4GALT2 to regulate intestinal metabolism and flora composition to improve inflammation in mice with colitis

BACKGROUND

Atractylenolide-1, an active component of Atractylodes Lancea, which is widely used to improve the gastrointestinal function. However, the efficacy and mechanism remain unclear in treating ulcerative colitis (UC).

PURPOSE

This study aimed to investigate the efficacy and the underlying mechanism of atractylenolide-1in UC.

METHODS

A dextran sulfate sodium (DSS)-induced UC mouse model was used to investigate the efficacy of atractylenolide-1. 16S DNA sequencing, GC-MS technique and transcriptome sequencing were used to detect the composition of mouse intestinal flora, the changes of metabolites and gene expression in mouse intestine. Compound-reaction-enzyme-gene network was used to find drug targets. Recombinant plasmid overexpression was used to verify drug targets in DSS mouse models.

RESULTS

The results showed that Atractylenolide-1 could significantly improve weight loss, diarrhea, blood in the stool, shortening of the colon, the loss of colonic goblet cells, reduction in mucoprotein MUC2, and tight junction proteins (zo-1, occludin) in mice with colitis. It reduced the inflammatory factors TNF-α, IL-6, IL-1β as well. The 16S sequencing showed that Atractylenolide-1 regulated the diversity and abundance of the intestinal flora in mice with colitis, and the analysis of flora enrichment indicated that the regulation of intestinal flora by atractylenolide-1 may be related to the regulation of metabolism. Correlation analysis of metabolomics and transcriptome showed that two genes SPHK1 and B4GALT2 related to the metabolism of fructose and galactose were regulated by atractylenolide-1. Further verification showed that atractylenolide-1 significantly inhibited the aberrance of SPHK1 and B4GALT2 in the colon with colitis. Meanwhile, it inhibited the activation of the PI3K-AKT pathway. SPHK1 and B4GALT2 overexpressing reversed the therapeutic effect of atractylenolide-1 in mice with colitis.

CONCLUSION

Atractylenolide-1 is a potential drug for the treatment of colitis by suppressing inflammation via the SPHK1/PI3K/AKT axis and by targeting SPHK1 and B4GAT2 to regulate fructose/galactose-related metabolism, thereby regulating the composition of the intestinal flora.

Tetramethylpyrazine prevents liver fibrotic injury in mice by targeting hepatocyte-derived and mitochondrial DNA-enriched extracellular vesicles

Liver fibrosis is the common consequence of almost all liver diseases and has become an urgent clinical problem without efficient therapies. Recent evidence has shown that hepatocytes-derived extracellular vesicles (EVs) play important roles in liver pathophysiology, but little is known about the role of damaged hepatocytes-derived EVs in hepatic stellate cell (HSC) activation and following fibrosis. Tetramethylpyrazine (TMP) from Ligusticum wallichii Franchat exhibits a broad spectrum of biological activities including liver protection. In this study, we investigated whether TMP exerted liver-protective action through regulating EV-dependent intercellular communication between hepatocytes and HSCs. Chronic liver injury was induced in mice by CCl₄ (1.6 mg/kg, i.g.) twice a week for 8 weeks. In the last 4 weeks of CCl₄ administration, mice were given TMP (40, 80, 160 mg·kg^-1·d^-1, i.g.). Acute liver injury was induced in mice by injection of a single dose of CCl₄ (0.8 mg/kg, i.p.). After injection, mice were treated with TMP (80 mg/kg) every 24 h. We showed that TMP treatment dramatically ameliorated CCl₄-induced oxidative stress and hepatic inflammation as well as acute or chronic liver fibrosis. In cultured mouse primary hepatocytes (MPHs), treatment with CCl₄ or acetaminophen resulted in mitochondrial dysfunction, release of mitochondrial DNA (mtDNA) from injured hepatocytes to adjacent hepatocytes and HSCs through EVs, mediating hepatocyte damage and fibrogenic responses in activated HSCs; pretreatment of MPHs with TMP (25 μM) prevented all these pathological effects. Transplanted serum EVs from TMP-treated mice prevented both initiation and progression of liver fibrosis caused by CCl₄. Taken together, this study unravels the complex mechanisms underlying the protective effects of TMP against mtDNA-containing EV-mediated hepatocyte injury and HSC activation during liver injury, and provides critical evidence inspiring the development of TMP-based innovative therapeutic agents for the treatment of liver fibrosis.