Taurochenodeoxycholic acid induces NR8383 cells apoptosis via PKC/JNK-dependent pathway

Trichinella spiralis -induced immunomodulation signatures on gut microbiota and metabolic pathways in mice

The hygiene hypothesis proposes that decreased exposure to infectious agents in developed countries may contribute to the development of allergic and autoimmune diseases. Trichinella spiralis, a parasitic roundworm, causes trichinellosis, also known as trichinosis, in humans. T. spiralis had many hosts, and almost any mammal could become infected. Adult worms lived in the small intestine, while the larvae lived in muscle cells of the same mammal. T. spiralis was a significant public health threat because it could cause severe illness and even death in humans who eat undercooked or raw meat containing the parasite. The complex interactions between gastrointestinal helminths, gut microbiota, and the host immune system present a challenge for researchers. Two groups of mice were infected with T. spiralis vs uninfected control, and the experiment was conducted over 60 days. The 16S rRNA gene sequences and untargeted LC/MS-based metabolomics of fecal and serum samples, respectively, from different stages of development of the Trichinella spiralis-mouse model, were examined in this study. Gut microbiota alterations and metabolic activity accompanied by parasite-induced immunomodulation were detected. The inflammation parameters of the duodenum (villus/crypt ratio, goblet cell number and size, and histological score) were involved in active inflammation and oxidative metabolite profiles. These profiles included increased biosynthesis of phenylalanine, tyrosine, and tryptophan while decreasing cholesterol metabolism and primary and secondary bile acid biosynthesis. These disrupted metabolisms adapted to infection stress during the enteral and parenteral phases and then return to homeostasis during the encapsulated phase. There was a shift from an abundance of Bacteroides in the parenteral phase to an abundance of probiotic Lactobacillus and Treg-associated-Clostridia in the encapsulated phase. Th2 immune response (IL-4/IL-5/IL-13), lamina propria Treg, and immune hyporesponsiveness metabolic pathways (decreased tropane, piperidine and pyridine alkaloid biosynthesis and biosynthesis of alkaloids derived from ornithine, lysine, and nicotinic acid) were all altered. These findings enhanced our understanding of gut microbiota and metabolic profiles of Trichinella -infected mice, which could be a driving force in parasite-shaping immune system maintenance.

Parabacteroides distasonis ameliorates hepatic fibrosis potentially via modulating intestinal bile acid metabolism and hepatocyte pyroptosis in male mice

Parabacteroides distasonis (P. distasonis) plays an important role in human health, including diabetes, colorectal cancer and inflammatory bowel disease. Here, we show that P. distasonis is decreased in patients with hepatic fibrosis, and that administration of P. distasonis to male mice improves thioacetamide (TAA)- and methionine and choline-deficient (MCD) diet-induced hepatic fibrosis. Administration of P. distasonis also leads to increased bile salt hydrolase (BSH) activity, inhibition of intestinal farnesoid X receptor (FXR) signaling and decreased taurochenodeoxycholic acid (TCDCA) levels in liver. TCDCA produces toxicity in mouse primary hepatic cells (HSCs) and induces mitochondrial permeability transition (MPT) and Caspase-11 pyroptosis in mice. The decrease of TCDCA by P. distasonis improves activation of HSCs through decreasing MPT-Caspase-11 pyroptosis in hepatocytes. Celastrol, a compound reported to increase P. distasonis abundance in mice, promotes the growth of P. distasonis with concomitant enhancement of bile acid excretion and improvement of hepatic fibrosis in male mice. These data suggest that supplementation of P. distasonis may be a promising means to ameliorate hepatic fibrosis.

Rapid identification of bear bile powder from other bile sources using chip-based nano-electrospray ionization tandem mass spectrometry

RATIONALE

Bear bile powder (BBP) is a widely used traditional Chinese medicine (TCM), and bile acids (BAs) are the main active components in BBP. Due to the scarcity of BBP resources, adulterations often occur in the market. Conventional methods to distinguish them are usually complicated and time-consuming. To enhance effectiveness and accuracy, a rapid and rough analytical method is desperately needed.

METHODS

In this study, a rapid strategy using chip-based nano-electrospray ionization tandem mass spectrometry (nano-ESI-MS/MS) was established to distinguish BBP from other sources of bile powder (BP). In addition, the results were further verified by ultra-high-performance liquid chromatography combined with high-resolution mass spectrometry (UPLC/MS).

RESULTS

The precision of the chip-based nano-ESI-MS/MS method was validated to be acceptable with relative standard deviation (RSD) <15%. The distinction between BBP and other sources of BP, including common adulterants of pig bile powder (PBP), cattle bile powder (CBP), sheep bile powder (SBP), and chicken bile powder (CkBP), can be observed in the spectra. By using orthogonal partial least-squares discriminant analysis (OPLS-DA), more potential m/z markers were investigated. A BAs-related m/z marker of 498.3 was discovered as a typical differential molecular ion peak and was identified as tauroursodeoxycholic acid (TUDCA) and taurochenodeoxycholic acid (TCDCA) in BBP.

CONCLUSIONS

The proposed strategy has simple sample pretreatment steps and significantly shortened analysis time. As an emerging technology, chip-based nano-ESI-MS not only provides a reference for the rapid distinction of adulterated Chinese medicines, but also provides some insights into the identification of other chemicals and foods.

Taurochenodeoxycholic Acid Increases cAMP Content via Specially Interacting with Bile Acid Receptor TGR5

Taurochenodeoxycholic acid (TCDCA) is one of the main components of bile acids (BAs). TCDCA has been reported as a signaling molecule, exerting anti-inflammatory and immunomodulatory functions. However, it is not well known whether those effects are mediated by TGR5. This study aimed to elucidate the interaction between TCDCA and TGR5. To achieve this aim, first, the TGR5 eukaryotic vector was constructed. The expression level of TGR5 in 293T cells was determined by immunofluorescence, real-time quantitative PCR (RT-PCR, qPCR), and Western blot. The luciferase assay, fluorescence microscopy, and enzyme-linked immunosorbent assay (ELISA) were recruited to check the interaction of TCDCA with TGR5. TCDCA treatment in 293T cells resulted in TGR5 internalization coupled with a significant increase in cAMP luciferase expression. Our results demonstrated that TCDCA was able to bind to the TGR5 receptor and activate it. These results provide an excellent potential therapeutic target for TCDCA research. Moreover, these findings also provide theoretical evidence for further TCDCA research.

Taurochenodeoxycholic acid mediates cAMP-PKA-CREB signaling pathway

Taurochenodeoxycholic acid (TCDCA) is one of the main effective components of bile acid, playing critical roles in apoptosis and immune responses through the TGR5 receptor. In this study, we reveal the interaction between TCDCA and TGR5 receptor in TGR5-knockdown H1299 cells and the regulation of inflammation via the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA)-cAMP response element binding (CREB) signal pathway in NR8383 macrophages. In TGR5-knockdown H1299 cells, TCDCA significantly activated cAMP level via TGR5 receptor, indicating TCDCA can bind to TGR5; in NR8383 macrophages TCDCA increased cAMP content compared to treatment with the adenylate cyclase (AC) inhibitor SQ22536. Moreover, activated cAMP can significantly enhance gene expression and protein levels of its downstream proteins PKA and CREB compared with groups of inhibitors. Additionally, TCDCA decreased tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, IL-8 and IL-12 through nuclear factor kappa light chain enhancer of activated B cells (NF-κB) activity. PKA and CREB are primary regulators of anti-inflammatory and immune response. Our results thus demonstrate TCDCA plays an essential anti-inflammatory role via the signaling pathway of cAMP-PKA-CREB induced by TGR5 receptor.

The cardiovascular protective effect and mechanism of calycosin and its derivatives

Cardiovascular disease is the main cause of mortality and morbidity in the world, especially in developing countries. Drug therapy is one of the main ways to treat cardiovascular diseases. Among them, great progress has been made in the treatment of cardiovascular diseases with traditional Chinese medicine. In terms of experimental research, the mechanism of traditional Chinese medicine in the treatment of cardiovascular diseases has been thoroughly discussed in vitro and in vivo. In terms of clinical treatment, traditional Chinese medicine with flavonoids, saponins and alkaloids as the main effective components has a definite effect on the treatment of cardiovascular diseases such as arrhythmia, myocardial ischemia, angina pectoris and myocardial infarction, with high safety and good application prospects. With the further research on the effective ingredients, mechanism and adverse reactions of traditional Chinese medicine, it will be beneficial to the effectiveness of traditional Chinese medicine, reduce side effects and promote the modernization of traditional Chinese medicine. Calycosin and its derivatives, the main bioactive flavonoids in Astragalus membranaceus have multiple biological effects, such as antioxidant, pro-angiogenesis, anti-tumour, and anti-inflammatory effects. Based on the above biological effects, calycosin has been shown to have good potential for cardiovascular protection. The potent antioxidant effect of calycosin may play an important role in the cardiovascular protective potential. For injured cardiac myocytes, calycosin and its derivatives can alleviate the cell damage mainly marked by the release of myocardial enzymes and reduce the death level of cardiac myocytes mainly characterized by apoptosis through various mechanisms. For vascular endothelial cells, calycosin also has multiple effects and multiple mechanisms, such as promoting vascular endothelial cell proliferation, exerting vasodilating effect and directly affecting the synthesis function of endothelial cells. The present review will address the bioactivity of calycosin in cardiovascular diseases such as protective effects on cardiac myocytes and vascular endothelial cells and elucidate main mechanism of calycosin and its derivatives to exert the above biological effects.

Serum Bile Acid Profiles Improve Clinical Prediction of Nonalcoholic Fatty Liver in T2DM patients

Background: The present study aimed to assess the ability of serum bile acid profiles to predict the development of nonalcoholic fatty liver (NAFL) in type 2 diabetes mellitus (T2DM) patients. Methods: Using targeted ultraperformance liquid chromatography (UPLC) coupled with triple quadrupole mass spectrometry (TQ/MS), we compared serum bile acid levels in T2DM patients with NAFL (n = 30) and age- and sex-matched T2DM patients without NAFL (n = 36) at the first time. Second, an independent cohort study of T2DM patients with NAFL (n = 17) and age- and sex-matched T2DM patients without NAFL (n = 20) was used to validate the results. The incremental benefits of serum biomarkers, clinical variables alone, or with biomarkers were then evaluated using receiver operating characteristic (ROC) curves and decision curve analysis. The area under the curve (AUC), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) were used to evaluate the biomarker predictive abilities. Results: The serum bile acid profiles in T2DM patients with NAFL were significantly different from T2DM patients without NAFL, as characterized by the significant elevation of LCA, TLCA, TUDCA, CDCA-24G, and TCDCA, which may be potential biomarkers for the identification of NAFL in T2DM patients. Based on the improvement in AUC, IDI, and NRI, the addition of 5 bile acids to a model with clinical variables statistically improved its predictive value. Similar results were found in the validation cohort. Conclusions: These results highlight that the detected biomarkers may contribute to the progression of NAFL in T2DM patients, and these biomarkers particularly in combination may help in the diagnosis of NAFL and allow earlier intervention in T2DM patients.

Transcriptome investigation of anti-inflammation and immuno-regulation mechanism of taurochenodeoxycholic acid

BACKGROUND

Taurochenodeoxycholic acid (TCDCA) is one of the major active components in bile acid. It was proven to have inhibitory activities on inflammation and also participate in host immuno-regulation. TCDCA exerts anti-inflammatory and immuno-regulatory effects through the glucocorticoid receptor (GR) mediated genomic signaling pathway and the G protein-coupled bile acid receptor 5 (TGR5) mediated AC-cAMP-PKA signaling pathway. However, it is unclear whether GR or TGR5 plays an important role in the regulatory effects of TCDCA. In order to further investigate this effects mechanism of TCDCA, the research use the transcriptome to identify the major genes and pathway in the anti-inflammatory and immuno-regulatory effects.

METHODS

After the Fibroblast-like synoviocytes (FLS) being treated by different concentrations (10- 5, 10- 6 and 10- 7 M) of TCDCA for 12 h, the resulting mRNA was analyzed by RNA-seq. The differentially expressed genes were screened from sequencing results using bioinformatics techniques. In the next step, other published literature were referred in order to find out whether those genes mentioned above are related to inflammation. The final selected differentially expressed genes associated with inflammation were then validated by q-PCR and western blot assays.

RESULTS

Five genes associated with anti-inflammatory and immuno-regulatory effects, include Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), Glutathione peroxidase 3 (GPX3), Serine/arginine-rich splicing factor-9 (SRSF9), Connective tissue growth factor (CTGF) and Cystatin B (CSTB) were identified. TCDCA at the concentrations of 10- 5, 10- 6 and 10- 7 M significantly (p < 0.05) up-regulate the mRNA and protein expression of SRSF9 and GPX3 and also up-regulate the mRNA expression of CSTB, CTGF and GAPDH. RNA-seq results of GPX3 and SRSF9 expression were consistent with q-PCR results, while q-PCR results of CTGF, GAPDH showed inconsistent with their RNA-seq results. Q-PCR result of CSTB expression also showed inconsistent with the RNA-seq result.

CONCLUSIONS

The anti-inflammatory and immuno-regulatory activities of TCDCA are proven to be related to the up-regulation expression of GPX3, SRSF9 and CSTB.

Bazhu Decoction, a Traditional Chinese Medical Formula, Ameliorates Cognitive Deficits in the 5xFAD Mouse Model of Alzheimer's Disease

Alzheimer’s disease (AD) is the most common neurodegenerative disorder associated with aging. There are currently no effective treatments for AD. Bazhu decoction (BZD), a traditional Chinese medicine (TCM) formula, has been employed clinically to alleviate AD. However, the underlying molecular mechanisms are still unclear. Here we found that middle- and high-doses of BZD ameliorated the behavioral aspects of 5xFAD transgenic mice in elevated plus maze, Y maze and Morris water maze tests. Moreover, BZD reduced the protein levels of BACE1 and PS1, resulting in a reduction of Aβ plaques. We also identified a beneficial effect of BZD on oxidative stress by attenuating MDA levels and SOD activity in the brains of 5xFAD mice. Together, these results indicate that BZD produces a dose-dependent positive effect on 5xFAD transgenic mouse model by decreasing APP processing and Aβ plaques, and by ameliorating oxidative damage. BZD may play a protective role in the cognitive and anxiety impairments and may be a complementary therapeutic option for AD.

Serum metabolomic alterations in Beagle dogs experimentally infected with Toxocara canis

Background

Toxocara canis, a globally distributed roundworm, can cause debilitating disease in dogs and humans; however, little is known about the metabolomic response of the hosts to T. canis infection. There is an increasing need to understand the metabolic mechanisms underlying the pathogenesis of T. canis infection in dogs. Here, we examined the metabolomic changes in Beagle dogsʼ serum following T. canis infection using LC-MS/MS.

Results

The metabolic profiles of Beagle dogsʼ serum were determined at 12 h, 24 h, 10 d and 36 d after oral infection with 300 infectious T. canis eggs by LC-MS/MS. We tested whether the T. canis-associated differentially abundant metabolites could distinguish the serum of infected dogs from controls, as measured by the area under the receiver operating characteristic (ROC) curve (AUC). The differentially expressed metabolites were further evaluated by principal components analysis and pathway enrichment analysis. A total of 5756 and 5299 ions were detected in ESI+ and ESI− mode, respectively. ROC curve analysis revealed nine and five metabolite markers, at 12 hpi and 24 hpi to 36 dpi, respectively, with potential diagnostic value for toxocariasis. The levels of taurocholate, estradiol, prostaglandins and leukotriene were significantly changed. Primary bile acid biosynthesis pathway, steroid hormone biosynthesis pathway and biosynthesis of unsaturated fatty acids pathway were significantly altered by T. canis infection.

Conclusions

These findings show that T. canis infection can induce several changes in the dog serum metabolome and that the metabolic signature associated with T. canis infection in dogs has potential for toxocariasis diagnosis.

A UPLC-MS-based metabolomics approach to reveal the attenuation mechanism of Caowu compatibility with Yunnan Baiyao

Yunnan Baiyao (YNBY) is a well-known traditional Chinese medicine containing Caowu (Aconiti kusnezoffii radix, CW). However, the application of YNBY is limited by the toxicity of CW. Notably, CW is not used alone in YNBY, but is combined with other herbs in a formula for clinical use. In the present study, the compatibility of the protective effects and mechanism of YNBY with the potential toxicity of CW was investigated. After combining with other compatible herbs, the serum metabolic disorder induced by CW can be regulated. Using UPLC-MS-based metabolomics, 63 endogenous serum metabolites were identified as being associated with the potential toxicity of CW, 17 of which were regulated to normal levels when CW was combined with other compatible herbs in YNBY. These regulated metabolites were closely related to glycerophospholipid metabolism, glycosylphosphatidylinositol (GPI)-anchor biosynthesis, tyrosine metabolism, and primary bile acid biosynthesis metabolic pathways. This study aims to evaluate the attenuation mechanism of CW compatibility with YNBY.

Yunnan Baiyao (YNBY) is a well-known traditional Chinese medicine containing Caowu (Aconiti kusnezoffii radix, CW).

Metabolomics-based evidence of the hypoglycemic effect of Ge-Gen-Jiao-Tai-Wan in type 2 diabetic rats via UHPLC-QTOF/MS analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Ge-Gen-Jiao-Tai-Wan (GGJTW) formula, derived from traditional Chinese herbal medicine, is composed of Pueraria montana var. lobata (Willd.) Sanjappa & Pradeep (Ge-Gen in Chinese), Coptis chinensis Franch (Huang-Lian), and Cinnamomum cassia (L.) J. Presl (Rou-Gui). GGJTW is used for treatment of diabetes in China, reflecting the potent hypoglycemic effect of its ingredients. However, little is known of the hypoglycemic effect of GGJTW and the underlying metabolic mechanism.

AIM OF THE STUDY

This study aimed to investigate the hypoglycemic effect of GGJTW in type 2 diabetic rats and the metabolic mechanism of action.

MATERIALS AND METHODS

Ultra high-performance liquid chromatography coupled with quadrupole-time-of-flight tandem mass spectrometry (UHPLC-QTOF/MS)-based metabolomics approach was used for monitoring hyperglycaemia induced by high-sugar high-fat fodder and streptozotocin (STZ), and the protective effect of GGJTW. Dynamic fasting blood glucose (FBG) levels, body weight, and biochemical parameters, including lipid levels, hepatic-renal function, and hepatic histopathology were used to confirm the hyperglycaemic toxicity and attenuation effects. An orthogonal partial least squared-discriminant analysis (OPLS-DA) approach highlighted significant differences in the metabolome of the healthy control, diabetic, and drug-treated rats. The metabolomics pathway analysis (MetPA) and Kyoto encyclopedia of genes and genomes (KEGG) database were used to investigate the underlying metabolic pathways.

RESULTS

Metabolic profiling revealed 37 metabolites as the most potential biomarker metabolites distinguishing GGJTW-treated rats from model rats. Most of the metabolites were primarily associated with bile acid metabolism and lipid metabolism. The most critical pathway was primary bile acid biosynthesis pathway involving the up-regulation of the levels of cholic acid (CA), chenodeoxycholic acid (CDCA), taurocholic acid (TCA), glycocholic acid (GCA), taurochenodesoxycholic acid (TCDCA), and taurine.

CONCLUSIONS

The significantly-altered metabolite levels indicated the hypoglycemic effect of GGJTW on diabetic rats and the underlying metabolic mechanism. This study will be meaningful for the clinical application of GGJTW and valuable for further exploration of the mechanism.