Combined systems pharmacology and fecal metabonomics to study the biomarkers and therapeutic mechanism of type 2 diabetic nephropathy treated with Astragalus and Leech

Combined use of Panax notoginseng and leech provides new insights into renal fibrosis: Restoration of mitochondrial kinetic imbalance

In this study, we aimed to investigate the protective effects of Panax notoginseng and leech (PL) on renal fibrosis and explore the mechanisms underlying their actions. For this study, we created an adenine-induced renal fibrosis model in SD rats to investigate the protective effect of PL on renal fibrosis and explore its underlying mechanism. Initially, we assessed the renal function in RF rats and found that Scr, BUN, and urine protein content decreased after PL treatment, indicating the protective effect of PL on renal function. Histological analysis using HE and Masson staining revealed that PL reduced inflammatory cell infiltration and decreased collagen fiber deposition in renal tissue. Subsequently, we analyzed the levels of α-SMA, Col-IV, and FN, which are the main components of the extracellular matrix (ECM), using IHC, RT-qPCR, and WB. The results demonstrated that PL was effective in reducing the accumulation of ECM, with PL1-2 showing the highest effectiveness. To further understand the underlying mechanisms, we conducted UPLC-MS/MS analysis on the incoming components of the PL1-2 group. The results revealed several associations between the differential components and antioxidant and mitochondrial functions. This was further confirmed by enzyme-linked immunosorbent assay and biochemical indexes, which showed that PL1-2 ameliorated oxidative stress by reducing ROS and MDA production and increasing GSH and SOD levels. Additionally, transmission electron microscopy results indicated that PL1-2 promoted partial recovery of mitochondrial morphology and cristae. Finally, using RT-qPCR and WB, an increase in the expression of mitochondrial fusion proteins Mfn1, Mfn2, and Opa1 after PL1-2 treatment was observed, coupled with a decline in the expression and phosphorylation of mitochondrial cleavage proteins Fis and Drp1. These findings collectively demonstrate that PL1-2 ameliorates renal fibrosis by reducing oxidative stress and restoring mitochondrial balance.

Hirudin in the Treatment of Chronic Kidney Disease

Chronic kidney disease (CKD) is a common public health concern. The global burden of CKD is increasing due to the high morbidity and mortality associated with it, indicating the shortcomings of therapeutic drugs at present. Renal fibrosis is the common pathology of CKD, which is characterized by glomerulosclerosis, renal tubular atrophy, and renal interstitial fibrosis. Natural hirudin is an active ingredient extracted from Hirudo medicinalis, which has been found to be the strongest natural specific inhibitor of thrombin. Evidence based on pharmacological data has shown that hirudin has important protective effects in CKD against diabetic nephrology, nephrotic syndrome, and renal interstitial fibrosis. The mechanisms of hirudin in treating CKD are mainly related to inhibiting the inflammatory response, preventing apoptosis of intrinsic renal cells, and inhibiting the interactions between thrombin and protease-activated receptors. In this review, we summarize the function and beneficial properties of hirudin for the treatment of CKD, and its underlying mechanisms.

Prospect of research on anti-atherosclerosis effect of main components of traditional Chinese medicine Yiqi Huoxue Huatan recipe through gut microbiota: A review

The incidence and mortality rates of cardiovascular diseases are on the rise globally, posing a severe threat to human health. Atherosclerosis (AS) is considered a multi-factorial inflammatory disease and the main pathological basis of cardiovascular and cerebrovascular diseases, as well as the leading cause of death. Dysbiosis of the gut microbiota can induce and exacerbate inflammatory reactions, accelerate metabolic disorders and immune function decline, and affect the progression and prognosis of AS-related diseases. The Chinese herbal medicine clinicians frequently utilize Yiqi Huoxue Huatan recipe, an effective therapeutic approach for the management of AS. This article reviews the correlation between the main components of Yiqi Huoxue Huatan recipe and the gut microbiota and AS to provide new directions and a theoretical basis for the prevention and treatment of AS.

Quantitative proteomics based bioactive proteins discovery and quality control of medicinal leeches

ETHNOPHARMACOLOGICAL RELEVANCE

Leech, a classical traditional Chinese medicine for promoting blood circulation and removing blood stasis, is mainly used in the clinical treatment of cardiovascular and cerebrovascular diseases. The discovery of activity proteins or peptides in the dead and dried medicinal leech is an important task with great challenges.

AIM OF THE STUDY

The aim of this study was to provide a basic proteome profile and help further discover active proteins and quality control for medicinal leeches, which would also provide insight into the research of animal medicines.

MATERIALS AND METHODS

Seventeen batches of dried medicinal leeches covering three species were collected from medicinal markets, which were authenticated by DNA barcoding. Then the proteome of different species leeches was profiled to reveal the significantly different proteins using label-free proteomics. The characteristic peptides were screened out based on biological pathways analysis, which were further absolutely quantified using the developed stable isotope-labeled based parallel reaction monitoring method.

RESULTS

Seventeen batches of leech materials were Whitmania pigra Whitman (WP), Whitmania laevis Whitman (WL) and Poecilobdella manillensis Lesson (PM), respectively. A total of 1,035 proteins (452 in WP, 425 in WL and 158 in PM) were identified. Among them, 90 overlapping proteins were mainly concentrated in diverse metabolic pathways and primarily localized in the cytoplasm and mitochondrial inner membrane, which mainly related to ATP binding, catalytic activity and structural molecular activity. In total of 51 uniquely expressed proteins (21 in WP, 23 in WL and 7 in PM), associated with multiple key signaling pathways, including Rap1, cGMP-PKG, PI3K-Akt, Wnt and HIF-1, etc., relevant to treating cardiovascular diseases, diabetes, cancer and even a variety of neurodegenerative diseases. Three proteins with potential bioactivities, including Neurohemerythrin, Hirudin and Eglin C, were selected as the quality makers and then quantified based on the characteristic peptides.

CONCLUSIONS

This work profiled the proteome of three species of leeches, and addressed potential active proteins of the medicinal leech, which would help to provide the potential molecular mechanisms involved in disease treatment. The proteomics-based approach developed in this work is not only useful for the discovery of proteins with potential bioactivities but also helpful for the bioactivity relevant quality control of animal medicines.

Study of the Mechanism of Astragali Radix in Treating Type 2 Diabetes Mellitus and Its Renal Protection Based on Enzyme Activity, Network Pharmacology, and Experimental Verification

Astragali Radix (AR) is a common Chinese medicine and food. This article aims to reveal the active role of AR in treating Type 2 diabetes mellitus (T2DM) and its renal protective mechanism. The hypoglycemic active fraction was screened by α-glucosidase and identified by UPLC-QE-Orbitrap-MS spectrometry. The targets and KEGG pathway were determined through the application of network pharmacology methodology. Molecular docking and molecular dynamics simulation technology were used for virtual verification. Subsequently, a mouse model of T2DM was established, and the blood glucose and renal function indexes of the mice after administration were analyzed to further prove the pharmacodynamic effect and mechanism of AR in the treatment of T2DM. HA was determined as the best hypoglycemic active fraction by the α-glucosidase method, with a total of 23 compounds identified. The main active components, such as calycoside-7-O-β-D-glucoside, methylnisoline, and formononetin, were revealed by network pharmacology. In addition, the core targets and the pathway have also been determined. Molecular docking and molecular dynamics simulation techniques have verified that components and targets can be well combined. In vivo studies have shown that AR can reduce blood sugar levels in model mice, enhance the anti-inflammatory and antioxidant activities of kidney tissue, and alleviate kidney damage in mice. And it also has regulatory effects on proteins such as RAGE, PI3K, and AKT. AR has a good therapeutic effect on T2DM and can repair disease-induced renal injury by regulating the RAGE/PI3K/Akt signaling pathway. This study provides ideas for the development of new drugs or dietary interventions for the treatment of T2DM.

Untargeted Metabolite Profiling of Adipose Tissue in Rats Exposed to Mepiquat

Mepiquat (Mep) is a contaminant produced by Maillard reaction with reducing sugar, free lysine and an alkylating agent under typical roasting conditions, particularly in the range of 200-240 °C. It has been reported that exposure to Mep is harmful to rats. However, its metabolic mechanism is still not clear. In this study, untargeted metabolomics was used to reveal the effect of Mep on the metabolic profile of adipose tissue in Sprague-Dawley rats. Twenty-six differential metabolites were screened out. Eight major perturbed metabolic pathways were found, which were linoleic acid metabolism, Phenylalanine, tyrosine, and tryptophan biosynthesis, phenylalanine metabolism, arachidonic acid metabolism, Glycine, serine, and threonine metabolism, glycerolipid metabolism, Alanine, aspartate, and glutamate metabolism, and glyoxylate and dicarboxylic acid metabolism. This study lays a solid foundation for clarifying the toxic mechanism of Mep.

A Clinical Trial of the Effects of a Dietary Pattern on Health Metrics and Fecal Metabolites in Volunteers With Risk of Cardiovascular Disease

The phenomenon of longevity in Guangxi of China proved to be closely relevant to its specific dietary habits, but the exact effects of this diet on health remain to be explored. In this work, fourteen screened volunteers with cardiovascular disease (CVD) risk followed a novel dietary pattern derived from centenarians of Guangxi, China for 2 weeks, then the effects of diet on human health were explored by measuring the health metrics and fecal metabolites. The results showed that the short-term dietary intervention significantly decreased the body weight, body mass index (BMI), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-c), mean systolic blood pressure (SBP), and diastolic blood pressure (DBP) levels, while it significantly increased high-density lipoprotein cholesterol (HDL-c) levels. Orthogonal partial least squares discriminant analysis (OPLS-DA) indicated a distinct separation in the fecal metabolic profiles of volunteers before and after the intervention. Nine of these metabolites showed significant differences, including two metabolites increased (butyrate and citrulline), seven metabolites decreased (threonine, choline, glycine, aspartate, alanine, N-acetylglutamic acid and lysine). Pathway and enrichment analysis showed that the reduction in CVD risk by dietary intervention mainly affected five pathways, which include arginine biosynthesis; aminoacyl-tRNA biosynthesis; glycine, serine and threonine metabolism; alanine, aspartate and glutamate metabolism; and valine, leucine and isoleucine biosynthesis. Herein, the Guangxi longevity dietary pattern can provide a feasible healthy diet strategy for reducing the CVD risk and human beings.

Potential Implications of Citrulline and Quercetin on Gut Functioning of Monogastric Animals and Humans: A Comprehensive Review

The importance of gut health in animal welfare and wellbeing is undisputable. The intestinal microbiota plays an essential role in the metabolic, nutritional, physiological, and immunological processes of animals. Therefore, the rapid development of dietary supplements to improve gut functions and homeostasis is imminent. Recent studies have uncovered the beneficial effects of dietary supplements on the immune response, microbiota, gut homeostasis, and intestinal health. The application of citrulline (a functional gut biomarker) and quercetin (a known potent flavonoid) to promote gut functions has gained considerable interest as both bioactive substances possess anti-inflammatory, anti-oxidative, and immunomodulatory properties. Research has demonstrated that both citrulline and quercetin can mediate gut activities by combating disruptions to the intestinal integrity and alterations to the gut microbiota. In addition, citrulline and quercetin play crucial roles in maintaining intestinal immune tolerance and gut health. However, the synergistic benefits which these dietary supplements (citrulline and quercetin) may afford to simultaneously promote gut functions remain to be explored. Therefore, this review summarizes the modulatory effects of citrulline and quercetin on the intestinal integrity and gut microbiota, and further expounds on their potential synergistic roles to attenuate intestinal inflammation and promote gut health.

Comprehensive Analysis of Fecal Microbiome and Metabolomics in Hepatic Fibrosis Rats Reveal Hepatoprotective Effects of Yinchen Wuling Powder From the Host-Microbial Metabolic Axis

Hepatic fibrosis (HF) is a typical consequence in the development of multiple chronic liver diseases, which is intimately related to the composition and metabolic status of gut microbiota. A myriad of evidence has indicated that traditional Chinese medicine can treat HF by regulating gut microbiota. Yinchen Wuling powder (YCWLP) is a famous traditional Chinese medicine prescription, which has been used to relieve liver diseases for thousands of years. YCWLP has demonstrated protective function on HF, but its effect on the alterations of gut microbiota is still unclear, and its explicit therapeutic mechanism also needs to be further elucidated. In this study, 16S rRNA gene sequencing and fecal metabolomics analysis were combined to investigate the influence of YCWLP on gut microbiota in HF rats and the interactions between gut microbiota and host metabolism. The results showed that YCWLP treatment significantly improved the disorder of multiple organ indices, HF-related cytokines and plasma LPS induced by HF. Masson's trichrome stainings also showed that YCWLP treatment could significantly alleviate the severity of HF in rats. Additionally, YCWLP could reverse the significant changes in the abundance of certain genera closely related to HF phenotype, including Barnesiella [Ruminococcus] and Christensenella. Meanwhile, YCWLP significantly increased the abundance of Bifidobacterium, Coprococcus and Anaerostipes, which are closely related to butyrate production. Metabolomics and Spearman's correlation analysis showed that YCWLP could regulate the disorder of arginine biosynthesis, sphingolipid metabolism and alanine, aspartate and glutamate metabolism in HF rats, and these regulations were intimately related to Barnesiella, [Ruminococcus], Christensenella, Coprococcus and Anaerostipes. By explaining the biological significance of the above results, we concluded that YCWLP might ameliorate HF by regulating the imbalance of gut microbiota, increasing the abundance of butyrate-producing bacteria to reduce ammonia production, promote ammonia degradation, and regulate pro-inflammatory cytokines and immune function.

HS-GC-IMS-Based metabonomics study of Baihe Jizihuang Tang in a rat model of chronic unpredictable mild stress

The aim of this study was to investigate the differences in volatile organic compounds (VOCs) obtained from the feces of a Baihe Jizihuang Tang (BHT)-treated rat depression model. Rats were subjected to chronic unpredictable mild stress (CUMS), and the differences in VOCs were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), NIST software, principal component analysis, and orthogonal partial least squares discriminant analysis. Eleven biomarkers were identified on the basis of VOC migration time, and their relative peak intensities were analyzed. A metabonomic model was established using multivariate statistical analysis. The study demonstrated the metabonomics of CUMS rats and the intervention effect of BHT and also highlighted the potential therapeutic effects of the traditional Chinese medicine (TCM) Jingfang for the clinical treatment of complex diseases, which was in line with the holistic and systemic approaches of TCM. This study augments the use of metabonomics based on HS-GC-IMS in research studies. Using this method, there is no need to pre-process samples by extraction or derivatization, and the VOC component of the sample can be detected directly and rapidly. In conclusion, this study establishes a simple, convenient, and fast technique, which can help identify clinical biomarkers for rapid medical diagnosis.

Fecal metabonomics combined with 16S rRNA gene sequencing to analyze the changes of gut microbiota in rats with kidney-yang deficiency syndrome and the intervention effect of You-gui pill

ETHNOPHARMACOLOGICAL RELEVANCE

A myriad of evidence have shown that kidney-yang deficiency syndrome (KYDS) is associated with metabolic disorders of the intestinal microbiota, while TCMs can treat KYDS by regulating gut microbiota metabolism. However, the specific interplay between KYDS and intestinal microbiota, and the intrinsic regulation mechanism of You-gui pill (YGP) on KYDS' gut microbiota remains largely unknown so far.

MATERIALS AND METHODS

In the present study, fecal metabonomics combined with 16S rRNA gene sequencing analysis were used to explore the mutual effect between KYDS and intestinal flora, and the intrinsic regulation mechanism of YGP on KYDS's gut microbiota. Rats' feces from control (CON) group, KYDS group and YGP group were collected, and metabolomic analysis was performed using ¹H NMR technique combined with multivariate statistical analysis to obtain differential metabolites. Simultaneously, 16S rRNA gene sequencing analysis based on the Illumina HiSeq sequencing platform and ANOVA analysis were used to analyze the composition of the intestinal microbiota in the stool samples and to screen for the significant altered microbiota at the genus level. After that, MetaboAnalyst database and PICRUSt software were apply to conduct metabolic pathway analysis and functional prediction analysis of the screened differential metabolites and intestinal microbiota, respectively. What's more, Pearson correlation analysis was performed on these differential metabolites and gut microbiota.

RESULTS

Using fecal metabonomics, KYDS was found to be associated with 21 differential metabolites and seven potential metabolic pathways. These metabolites and metabolic pathways were mainly involved in amino acid metabolism, energy metabolism, methylamine metabolism, bile acid metabolism and urea cycle, and short-chain fatty acid metabolism. Through 16S rRNA gene sequencing analysis, we found that KYDS was related to eleven different intestinal microbiotas. These gut microbiota were mostly involved in amino acid metabolism, energy metabolism, nervous, endocrine, immune and digestive system, lipid metabolism, and carbohydrate metabolism. Combined fecal metabonomics and 16S rRNA gene sequencing analysis, we further discovered that KYDS was primarily linked to three gut microbiotas (i.e. Bacteroides, Desulfovibrio and [Eubacterium]_coprostanoligenes_group) and eleven related metabolites (i.e. deoxycholate, n-butyrate, valine, isoleucine, acetate, taurine, glycine, α-gluconse, β-glucose, glycerol and tryptophan) mediated various metabolic disorders (amino acid metabolism, energy metabolism, especially methylamine metabolism, bile acid metabolism and urea cycle, short-chain fatty acid metabolism. nervous, endocrine, immune and digestive system, lipid metabolism, and carbohydrate metabolism). YGP, however, had the ability to mediate four kinds of microbes (i.e. Ruminiclostridium_9, Ruminococcaceae_UCG-007, Ruminococcaceae_UCG-010, and uncultured_bacterium_f_Bacteroidales_S24-7_group) and ten related metabolites (i.e. deoxycholate, valine, isoleucine, alanine, citrulline, acetate, DMA, TMA, phenylalanine and tryptophan) mediated amino acid metabolism, especially methylamine metabolism, bile acid metabolism and urea cycle, short-chain fatty acid metabolism, endocrine, immune and digestive system, and lipid metabolism, thereby exerting a therapeutic effect on KYDS rats.

CONCLUSION

Overall, our findings have preliminary confirmed that KYDS is closely related to metabolic and microbial dysbiosis, whereas YGP can improve the metabolic disorder of KYDS by acting on intestinal microbiota. Meanwhile, this will lay the foundation for the further KYDS's metagenomic research and the use of intestinal microbiotas as drug targets to treat KYDS.

Study on Hypoglycemic Effect of the Drug Pair of Astragalus Radix and Dioscoreae Rhizoma in T2DM Rats by Network Pharmacology and Metabonomics

Type 2 diabetes mellitus (T2DM) is a metabolic disease accompanied by a series of diseases such as diabetic nephropathy. The drug pair (HS) of Astragalus Radix (HQ) and Dioscoreae Rhizoma (SY) was designed by Dr. Shi Jinmo to improve the treatment of T2DM. However, the exact mechanism involved requires further clarification. In this work, 1H-NMR-based metabonomics and network pharmacology were adopted. Metabolic profiling indicated that the metabolic perturbation was reduced after HS treatment. The results found 21 biomarkers. According to the network pharmacology, we found that the regulation of T2DM was primarily associated with 18 active compounds in HS. These active compounds mainly had an effect on 135 targets. Subsequently, combining network pharmacology and metabonomics, we found four target proteins, which indicated that HS has potential hypoglycemic effects through regulating monoamine oxidases B (MAOB), acetyl-CoA carboxylase 1 (ACACA), carbonic anhydrase 2 (CA2), and catalase (CAT). In conclusion, the result showed that these four targets might be the most relevant targets for the treatment of T2DM with HS. This study clarified the mechanism of HS in the treatment of T2DM and also confirmed the feasibility of combining metabonomics and network pharmacology to study the mechanisms of traditional Chinese medicine (TCM). In the future, this approach may be a potentially powerful tool to discovery active components of traditional Chinese medicines and elucidate their mechanisms.

Incipient Diabetes Treated with Long-Term Classical Prescription

BACKGROUND

Diabetes mellitus (DM) belongs to the progressive and irreversible disease. With the development of the disease, the function of beta cells declines significantly. Current treatments cannot reverse the course of the disease. The role of traditional Chinese medicine (TCM) in the DM treatment has been recognized widely, while there are few long-term observation reports. In this study, we introduced a case of DM treated by classical prescription alone for 10 years, which would provide the reference for clinical practice.

CASE PRESENTATION

A 64-year-old male complained of a 2-month history of dry mouth, frequent urination, and blurred vision and found increased blood glucose for 3 days. The patient's glycated hemoglobin was 14.2%, fasting plasma glucose fluctuated at 12-15 mmol/L, and urinary albumin excretion rate (UAER) was 32.9 μg/min. The male was treated with 10 years of continuous classical prescription alone. After 3 months of TCM treatment, the patient's blood glucose level decreased significantly and blurred vision symptoms improved. With continued TCM treatment, his UAER normalized. Subsequently, he continued outpatient consultation, and his TCM prescription was adjusted according to clinical symptoms. After 10 years of continuous TCM treatment, his blood glucose remained stable, urinary microalbumin quantitation showed no abnormalities, and blurred vision disappeared.

CONCLUSIONS

This case provides specific treatment plans and effective references for long-term control of blood glucose, prevention and treatment of diabetes complications, delay of disease progression, and protection of impaired islet function in the treatment of diabetes with TCM. TCM may become a meaningful alternative DM treatment in the future.

Application of metabolomics for unveiling the therapeutic role of traditional Chinese medicine in metabolic diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicine has been practiced for thousands of years in China and some Asian countries. Traditional Chinese Medicine (TCM) is characterized as multi-component and multiple targets in disease therapy, and it is a great challenge for elucidating the mechanisms of TCM.

AIM OF THE REVIEW

Comprehensively summarize the application of metabolomics in biomarker discovery, stratification of TCM syndromes, and mechanism underlying TCM therapy on metabolic diseases.

METHODS

This review systemically searched the publications with key words such as metabolomics, traditional Chinese medicine, metabolic diseases, obesity, cardiovascular disease, diabetes mellitus in "Title OR Abstract" in major databases including PubMed, the Web of Science, Google Scholar, Science Direct, CNKI from 2010 to 2019.

RESULTS

A total of 135 papers was searched and included in this review. An overview of articles indicated that metabolic characteristics may be a hallmark of different syndromes/models of metabolic diseases, which provides a new perspective for disease diagnosis and therapeutic optimization. Moreover, TCM treatment has significantly altered the metabolic perturbations associated with metabolic diseases, which may be an important mechanism for the therapeutic effect of TCM.

CONCLUSIONS

Until now, many metabolites and differential biomarkers related to the pathogenesis of metabolic diseases and TCM therapy have been discovered through metabolomics research. Unfortunately, the biological role and mechanism of disease-related metabolites were largely unclarified so far, which warrants further investigation.

Integrated Systems Pharmacology, Urinary Metabonomics, and Quantitative Real-Time PCR Analysis to Uncover Targets and Metabolic Pathways of the You-Gui Pill in Treating Kidney-Yang Deficiency Syndrome

Kidney-yang deficiency syndrome (KYDS) is a metabolic disease caused by a neuro-endocrine disorder. The You-gui pill (YGP) is a classic traditional Chinese medicine (TCM) formula for the treatment of KYDS and has been widely used to warm and recuperate KYDS clinically for hundreds of years in China. However, it is unknown whetherthe corresponding targets and metabolic pathways can also be found via using metabonomics based on one platform (e.g., 1H NMR) to study different biological samples of KYDS. At the same time, relevant reports on further molecular verification (e.g., RT-qPCR analysis) of these targets associated with biomarkers and metabolic pathways have not yet, to our knowledge, been seen in KYDS's research. In the present study, a comprehensive strategy integrating systems pharmacology and 1H NMR-based urinary metabonomics analysis was proposed to identify the target proteins and metabolic pathways that YGP acts on KYDS. Thereafter, further validation of target proteins in kidney tissue was performed through quantitative real-time PCR analysis (RT-qPCR). Furthermore, biochemical parameters and histopathological analysis were studied. As a result, seven target proteins (L-serine dehydratase; phosphoenolpyruvate carboxykinase; spermidine synthase; tyrosyl-tRNA synthetase, glutamine synthetase; 3-hydroxyacyl-CoA dehydrogenase; glycine amidinotransferase) in YGP were discovered to play a therapeutic role in KYDS via affecting eight metabolic pathways (glycine, serine and threonine metabolism; butanoate metabolism; TCA cycle, etc.). Importantly, three target proteins (i.e., 3-hydroxyacyl-CoA dehydrogenase; glutamine synthetase; and glycine amidinotransferase) and two metabolic pathways (butanoate metabolism and dicarboxylate metabolism) related to KYDS, to our knowledge, had been newly discovered in our study. The mechanism of action mainly involved energy metabolism, oxidative stress, ammonia metabolism, amino acid metabolism, and fatty acid metabolism. In short, our study demonstrated that targets and metabolic pathways for the treatment of KYDS by YGP can be effectively found via combining with systems pharmacology and urinary metabonomics. In addition to this, common and specific targets and metabolic pathways of KYDS treated by YGP can be found effectively by integration with the analysis of different biological samples (e.g., serum, urine, feces, and tissue). It is; therefore, important that this laid the foundation for deeper mechanism research and drug-targeted therapy of KYDS in future.

Gut microbiota, a new frontier to understand traditional Chinese medicines

As an important component of complementary and alternative medicines, traditional Chinese medicines (TCM) are gaining more and more attentions around the world because of the powerful therapeutic effects and less side effects. However, there are still some doubts about TCM because of the questionable TCM theories and unclear biological active compounds. In recent years, gut microbiota has emerged as an important frontier to understand the development and progress of diseases. Together with this trend, an increasing number of studies have indicated that drug molecules can interact with gut microbiota after oral administration. In this context, more and more studies pertaining to TCM have paid attention to gut microbiota and have yield rich information for understanding TCM. After oral administration, TCM can interact with gut microbiota: (1) TCM can modulate the composition of gut microbiota; (2) TCM can modulate the metabolism of gut microbiota; (3) gut microbiota can transform TCM compounds. During the interactions, two types of metabolites can be produced: gut microbiota metabolites (of food and host origin) and gut microbiota transformed TCM compounds. In this review, we summarized the interactions between TCM and gut microbiota, and the pharmacological effects and features of metabolites produced during interactions between TCM and gut microbiota. Then, focusing on gut microbiota and metabolites, we summarized the aspects in which gut microbiota has facilitated our understanding of TCM. At the end of this review, the outlooks for further research of TCM and gut microbiota were also discussed.