[Difference in liver injury induced by dictamnine between males and females: based on untargeted metabolomics].

In recent years, reports of adverse reactions related to traditional Chinese medicine(TCM) have been on the rise, especially some traditionally considered "non-toxic" TCM(such as Dictamni Cortex). This has aroused the concern of scholars. This study aims to explore the metabolomic mechanism underlying the difference in liver injury induced by dictamnine between males and females through the experiment on 4-week-old mice. The results showed that the serum biochemical indexes of liver function and organ coefficients were significantly increased by dictamnine(P<0.05), and hepatic alveolar steatosis was mainly observed in female mice. However, no histopathological changes were observed in the male mice. Furthermore, a total of 48 differential metabolites(such as tryptophan, corticosterone, and indole) related to the difference in liver injury between males and females were screened out by untargeted metabolomics and multivariate statistical analysis. According to the receiver operating characteristic(ROC) curve, 14 metabolites were highly correlated with the difference. Finally, pathway enrichment analysis indicated that disorders of metabolic pathways, such as tryptophan metabolism, steroid hormone biosynthesis, and ferroptosis(linoleic acid metabolism and arachidonic acid metabolism), may be the potential mechanism of the difference. Liver injury induced by dictamnine is significantly different between males and females, which may be caused by the disorders of tryptophan metabolism, steroid hormone biosynthesis, and ferroptosis pathways.

Psoraleae Fructus Ethanol Extract Induced Hepatotoxicity via Impaired Lipid Metabolism Caused by Disruption of Fatty Acid ß-Oxidation.

Herb-induced liver injury (HILI) is gradually increasing, and Psoraleae Fructus (PF) has been reported to induce hepatotoxicity. However, its underlying toxicity mechanism has been only poorly revealed. In this paper, we attempted to explore the liver injury and mechanism caused by Psoraleae Fructus ethanol extract (PFE). First, we administered PFE to mice for 4 weeks and evaluated their serum liver function indices. H&E staining was performed to observe the pathological changes of the livers. Oil red O staining was used to visualize hepatic lipids. Serum-untargeted metabolomics and liver proteomics were used to explore the mechanism of PF hepatotoxicity, and transmission electron microscopy was determined to assess mitochondria and western blot to determine potential target proteins expression. The results showed that PFE caused abnormal liver biochemical indicators and liver tissue injury in mice, and there was substantial fat accumulation in liver tissue in this group. Furthermore, metabolomic analysis showed that PFE changed bile acid synthesis, lipid metabolism, etc., and eight metabolites, including linoleic acid, which could be used as potential biomarkers of PFE hepatotoxicity. Proteomic analysis revealed that differential proteins were clustered in the mitochondrial transmembrane transport, the long-chain fatty acid metabolic process and purine ribonucleotide metabolic process. Multiomics analysis showed that eight pathways were enriched in both metabolomics and proteomics, such as bile secretion, unsaturated fatty acid biosynthesis, and linoleic acid metabolism. The downregulation of SLC27A5, CPT1A, NDUFB5, and COX6A1 and upregulation of cytochrome C and ABCC3 expressions also confirmed the impaired fatty acid oxidative catabolism. Altogether, this study revealed that PFE induced hepatotoxicity by damaging mitochondria, reducing fatty acid ß-oxidation levels, and inhibiting fatty acids ingested by bile acids.

Multi-Omics Integration to Reveal the Mechanism of Hepatotoxicity Induced by Dictamnine.

Herb-induced liver injury (HILI) has become a great concern worldwide due to the widespread usage of herbal products. Among these products is Dictamni Cortex (DC), a well-known Traditional Chinese Medicine (TCM), widely used to treat chronic dermatosis. Dictamni Cortex has drawn increasing attention because of its hepatotoxicity caused by the hepatotoxic component, dictamnine. However, the potential hepatotoxicity mechanism of dictamnine remains unclear. Therefore, this study aimed to use the multi-omics approach (transcriptomic, metabolomic, and proteomic analyses) to identify genes, metabolites, and proteins expressions associated with dictamnine-induced hepatotoxicity. A study on mice revealed that a high dose of dictamnine significantly increases serum aspartate aminotransferase (AST) activity, total bilirubin (TBIL), and direct bilirubin (DBIL) levels, the relative liver weight and liver/brain weight ratio in female mice (P < 0.05 and P < 0.01), compared to the normal control group. Liver histologic analysis further revealed a high dose of dictamnine on female mice caused hepatocyte vesicular steatosis characterized by hepatocyte microvesicles around the liver lobules. The expressed genes, proteins, and metabolites exhibited strong associations with lipid metabolism disorder and oxidative stress. Dictamnine caused increased oxidative stress and early hepatic apoptosis via up-regulation of glutathione S transferase a1 (GSTA1) and Bax/Bcl-2 ratio and down-regulation of the antioxidative enzymes superoxide dismutase (SOD), catalase, and glutathione peroxidase 1 (GPx-1). Besides, the up-regulation of Acyl-CoA synthetase long-chain family member 4 (ACSL4) and down-regulation of acetyl-coa acetyltransferase 1 (ACAT1) and fatty acid binding protein 1 (FABP-1) proteins were linked to lipid metabolism disorder. In summary, dictamnine induces dose-dependent hepatotoxicity in mice, which impairs lipid metabolism and aggravates oxidative stress.

Components synergy between stilbenes and emodin derivatives contributes to hepatotoxicity induced by Polygonum multiflorum.

Polygonum multiflorum Thunb. (PM) is a famous traditional Chinese medicine with liver tonic effect, but arousing great concerns for hepatotoxicity issue. In this study, we elucidated the contribution of the two major compounds, emodin-8-O-ß-D-glucoside (EG) and 2,3,5,4´-tetrahydroxyl diphenylethylene-2-O-glucoside (TSG), in PM-induced liver injury.Based on LC-MS, the two concerned compounds were detected simultaneously in the sera of patients with PM-induced liver injury. In the lipopolysaccharide (LPS)-mediated inflammatory stress rat model, by the analysis of plasma biochemistry and liver histopathology, we observed that the solo treatment of EG, not TSG, could induce significant liver injury; and the combined administration of EG and TSG caused more severe liver injury than that of EG.Metabolomics analysis revealed that the EG-triggered liver injury was associated with significant disturbances of sphingolipids and primary bile acids metabolism pathways. In the combined administration group, much more disturbances in EG-triggered metabolic pathways, as well as alterations of several additional pathways such as retinol metabolism and vitamin B6 metabolism, were observed.Taken together, we considered EG was involved in the idiosyncratic liver injury of PM, and TSG played a synergetic role with EG, which contributed to the understanding of the hepatotoxic basis of PM.

Risk profiling using metabolomic characteristics for susceptible individuals of drug-induced liver injury caused by Polygonum multiflorum.

Idiosyncratic drug-induced liver injury (IDILI) is a rare but potentially severe adverse drug reaction. To date, identifying individuals at risk for IDILI remains challenging. This is a prospective study, where a nested case-control (1:5) design was adopted. For six patients who had abnormalities in liver function test after Polygonum multiflorum Thunb. (PM) ingestion (susceptible group), 30 patients with normal liver function were matched (tolerant group). Based on liquid chromatography-mass spectrometry, metabolomics analysis was done on serum samples prior to PM ingestion, to screen the differential metabolites and characterize metabolomic profiles of patient serum in the two groups. Multivariate analysis showed that there were remarkable separations between susceptible and tolerant groups. A total of 25 major differential metabolites were screened out, involving glycerophospholipid metabolism, sphingolipid metabolism, fatty acid metabolism, histidine metabolism and aromatic amino acid metabolism. Wherein, the area under the curve of the receiver operating characteristic curves of metabolites PE 22:6, crotonoyl-CoA, 2E-tetradecenoyl-CoA, phenyllactic acid, indole-5,6-quinone, phosphoribosyl-ATP were all greater than 0.9. The overall serum metabolic profile comprising of 25 metabolites could clearly distinguish susceptible and tolerant groups. This proof-of-concept study used metabolomics to characterize the metabolic profile of IDILI risk individuals before drug ingestion for the first time. The metabolome characteristics in patient serum before PM ingestion may predict the risk of liver injury after PM ingestion.

Epigallocatechin Gallate During Dietary Restriction - Potential Mechanisms of Enhanced Liver Injury.

Green tea extract (GTE) is popular in weight loss, and epigallocatechin gallate (EGCG) is considered as the main active component. However, GTE is the primary cause of herbal and dietary supplement-induced liver injury in the United States. Whether there is a greater risk of liver injury when EGCG is consumed during dieting for weight loss has not been previously reported. This study found for the first time that EGCG could induce enhanced lipid metabolism pathways, suggesting that EGCG had the so-called "fat burning" effect, although EGCG did not cause liver injury at doses of 400 or 800 mg/kg in normal mice. Intriguingly, we found that EGCG caused dose-dependent hepatotoxicity on mice under dietary restriction, suggesting the potential combination effects of dietary restriction and EGCG. The combination effect between EGCG and dietary restriction led to overactivation of linoleic acid and arachidonic acid oxidation pathways, significantly increasing the accumulation of pro-inflammatory lipid metabolites and thus mediating liver injury. We also found that the disruption of Lands' cycle and sphingomyelin-ceramides cycle and the high expression of taurine-conjugated bile acids were important metabolomic characteristics in EGCG-induced liver injury under dietary restriction. This original discovery suggests that people should not go on a diet while consuming EGCG for weight loss; otherwise the risk of liver injury will be significantly increased. This discovery provides new evidence for understanding the "drug-host" interaction hypothesis of drug hepatotoxicity and provides experimental reference for clinical safe use of green tea-related dietary supplements.

Network pharmacology oriented study reveals inflammatory state-dependent dietary supplement hepatotoxicity responses in normal and diseased rats.

Rhubarb, a well-used herbal and dietary supplement, has been widely used as a laxative in many countries. The dietary supplement rhubarb may reveal differential hepatotoxicity responses in normal and diseased subjects; however, its underlying mechanism is unclear. By using a network pharmacology approach, we found that the components contained in rhubarb had associations with a liver disease-related protein network that could be enriched into two subnetworks: a pro-inflammatory protein network associated with liver inflammation and an anti-inflammatory protein network related to liver fibrosis. In addition, macrophages were found to have an association with these subnetworks. Herein, the differential toxicity responses of rhubarb in normal and diseased rats were illustrated by in vivo pharmacology experiments. Rhubarb induced liver injury in normal rats with dose-dependent increases in the pro-inflammatory response; in contrast, it failed to induce hepatotoxic effects in a liver fibrosis rat model and was accompanied by an increase in anti-inflammatory protein expression. Further study showed elevation of high mobility group box-1 (HMGB1) in the sera and liver tissues and remarkable pro-inflammatory activation of Kupffer cells in liver tissue; these phenomena were associated with the hepatotoxic effect of rhubarb and could be blocked by inhibiting either HMGB1 or Kupffer cells through glycyrrhizin or GdCl3, respectively. Interestingly, we also observed attenuated pro-inflammatory activation of Kupffer cells in a liver fibrosis rat model together with a non-hepatotoxic response to rhubarb. These results suggest that the divergent immune states in normal and diseased subjects may contribute to the differential toxicity responses to rhubarb.

Susceptibility-Related Factor and Biomarkers of Dietary Supplement Polygonum multiflorum-Induced Liver Injury in Rats.

Polygonum multiflorum [PM, synonym Reynoutria multiflora (Thunb.) Moldenke.], a well-known and commonly used Traditional Chinese Medicine and herbal dietary supplement for nourishing the kidney and liver, etc., has aroused wide concern for its reported potential hepatotoxicity. Previous clinical cases and experimental studies have suggested that mild immune stress (MIS) may be one of the susceptibility-related factors of idiosyncratic drug-induced liver injury (IDILI) caused by PM. In this paper, we found that the same dose of PM caused abnormal liver biochemical indicators and liver tissue damage in MIS model rats, while it did not result in liver injury in normal rats, further confirming that MIS is a susceptibility factor for PM-IDILI. Plasma chemokine/cytokine profiling indicated that the MIS model group was significantly different from the other groups, showing a significant upregulation of plasma chemokines, while the MIS/PM group showed upregulated expression of chemokines or pro-inflammatory cytokines. Liver histopathological examination indicated a small amount of inflammatory cytokine infiltration in the MIS group, but no hepatocyte injury, consistent with the plasma profiles of increased chemokines and unchanged inflammatory cytokines. Notably, metabolomics characterization showed that MIS caused reprogramming of these metabolic pathways (such as phenylalanine and glutamate pathways), which was associated with acute phase reactions and inflammatory responses. These results suggested that MIS may promote an immune response to the initial cellular injury induced by PM in the liver, and MIS-induced upregulation of chemokines and metabolic reprogramming may an important mechanism that mediates the susceptibility to PM-IDILI. Furthermore, via receiver operating characteristic (ROC) curves analysis, we identified 12 plasma cytokines (e.g., IP-10, MCP-1 and MIP-1α) and nine metabolomics biomarkers (e.g., L-Phenylalanine, Creatinine, and L-glutamine) with differential capabilities (all ROC AUC > 0.9) of identifying susceptibility model animals from normal ones, which might be of referable value for the clinical recognition of PM-IDILI susceptible individuals.

Bioassay based screening for the antiplatelet aggregation quality markers of Polygonum multiflorum with UPLC and chemometrics.

Currently, an increasing number of patients are seriously affected by acute thrombotic events. In China, Polygonum multiflorum (PM) is commonly used to treat diseases associated with thrombosis. Our previous work showed that PM could inhibit the platelet aggregation that plays a key role in the pathogenesis of thrombosis. However, the constituents of PM are complicated, and quality control methods cannot completely ensure the quality and clinical efficacy. In an attempts to explore this problem, we constructed a direct bioassay method to evaluate the antiplatelet aggregation effects of PM. To ensure the precision and reliability of this bioassay, we optimized and standardized the experimental conditions and then tested the standardized bioassay by analyzing 10 PM samples. Additionally, we combined chemical and biological evaluation methods to identify antiplatelet aggregation markers. The evaluation indicated that 10 samples of PM could inhibit platelet aggregation and there was a notable difference in biopotency between the different PM groups. Chemical fingerprints revealed variations in the contents of the 7 main peaks. Trans-2,3,5,4'-tetrahydroxy-stilbene-2-O-ß-d-glucoside and catechin might be active constituents of antiplatelet aggregation as determined by spectrum-effect relationships. This work indicates that bioassay and spectrum-effect relationships are useful tools to associate sample quality with the potential chemical markers linked to the clinical effects of Traditional Chinese Medicines.

Natural products berberine and curcumin exhibited better ameliorative effects on rats with non-alcohol fatty liver disease than lovastatin.

Studies have shown that satins and herbal products have potential to treat non-alcohol fatty liver disease (NAFLD) in clinic. However, no study has compared their effects, and their mechanisms remain unresolved. Here, we choose lovastatin and two herbal products including berberine and curcumin to compare their effects in treating NAFLD. NAFLD model was established by high fat food, and rats were administrated with lovastatin, berberine, curcumin, berberine + curcumin at the dosage of 100, 100, 100, 50 + 50 mg/kg bw, respectively. The body weight, visceral fat gain, histological inspection and serum parameters were studied to exam the curative effects. In addition, mediators including SREBP-1c, caveolin-1, pERK, NF-κB, TNF-α, and pJNK were studied. Results showed that berberine + curcumin group exhibited lower body and fat weigh compared with lovastatin group. Biochemical assays showed that LDL-c, ALT, AST, ALP, MDA, LSP level were lower in berberine + curcumin group compared with lovastatin group. Lower expression of SREBP-1c, pERK, TNF-α, and pJNK were also observed in berberine + curcumin group. We conclude that combination of curcumin and berberine exhibited better ameliorative effects in treating NAFLD than lovastatin, and this enhanced effect is associated with oxidative stress, hepatic inflammation and lipid metabolism.

[Antiplatelet aggregation bioactivity of Polygoni Multiflori Radix with chemical fingerprints and spectrum-effect correlation analysis].

To explore the active substance of antiplatelet aggregation of Polygoni Multiflori Radix by using chemical fingerprints and antiplatelet aggregation bioactivity test for spectrum-effect correlation analysis. The Polygoni Multiflori Radix was tested by antiplatelet aggregation in vitro, and the results showed that 50% aqueous ethanol extract of Polygoni Multiflori Radix had more potent antiplatelet aggregation effect than 10% or 90% aqueous ethanol extract, and ultrasonic extraction was superior to refluxing extraction in the aspect of antiplatelet aggregation. The antiplatelet aggregation bioactivity of the different Polygoni Multiflori Radix extracts was evaluated and the results showed that the inhibition rate was 32.03%-74.56%. Spectrum-effect correlation analysis indicated that trans-stilbene glucoside, cis-stilbene glucoside and catechinic acid had higher correlation coefficient and they were 0.963 (P<0.01), 0.902 (P<0.01) and 0.656 (P<0.05) respectively; furthermore, all of the above three compounds demonstrated significant antiplatelet aggregation bioactivities. Considering their content difference in Polygoni Multiflori Radix, we calculated the relative active contributions, and the results suggested that trans-stilbene glucoside was the main active substance of Polygoni Multiflori Radix in the aspect of antiplatelet aggregation in vitro.

Screening for main components associated with the idiosyncratic hepatotoxicity of a tonic herb, Polygonum multiflorum.

The main constituents of a typical medicinal herb, Polygonum multiflorum (Heshouwu in Chinese), that induces idiosyncratic liver injury remain unclear. Our previous work has shown that cotreatment with a nontoxic dose of lipopolysaccharide (LPS) and therapeutic dose of Heshouwu can induce liver injury in rats, whereas the solo treatment cannot induce observable injury. In the present work, using the constituent "knock-out" and "knock-in" strategy, we found that the ethyl acetate (EA) extract of Heshouwu displayed comparable idiosyncratic hepatotoxicity to the whole extract in LPS-treated rats. Results indicated a significant elevation of plasma alanine aminotransferase, aspartate aminotransferase, and liver histologic changes, whereas other separated fractions failed to induce liver injury. The mixture of EA extract with other separated fractions induced comparable idiosyncratic hepatotoxicity to the whole extract in LPS-treated rats. Chemical analysis further revealed that 2,3,5,4'-tetrahydroxy trans-stilbene-2-O-ß-glucoside (trans-SG) and its cis-isomer were the two major compounds in EA extract. Furthermore, the isolated cis-, and not its trans-isomer, displayed comparable idiosyncratic hepatotoxicity to EA extract in LPS-treated rats. Higher contents of cis-SG were detected in Heshouwu liquor or preparations from actual liver intoxication patients associated with Heshouwu compared with general collected samples. In addition, plasma metabolomics analysis showed that cis-SG-disturbing enriched pathways remarkably differed from trans-SG ones in LPS-treated rats. All these results suggested that cis-SG was closely associated with the idiosyncratic hepatotoxicity of Heshouwu. Considering that the cis-trans isomerization of trans-SG was mediated by ultraviolet light or sunlight, our findings serve as reference for controlling photoisomerization in drug discovery and for the clinical use of Heshouwu and stilbene-related medications.

Poria Attenuates Idiosyncratic Liver Injury Induced by Polygoni Multiflori Radix Praeparata.

The hepatotoxicity induced by Polygoni Multiflori Radix Praeparata (PM) has aroused great concern throughout the world. Hence, it is worthwhile to perform studies on the detoxification with the combined use of medicinal herbs based on the compatibility theory of traditional Chinese medicine. In this work, the rat model of PM/LPS-induced idiosyncratic liver injury was used. The effects of Poria, Licorice, and Panax notoginseng on rats of PM/LPS-induced liver injury were investigated respectively, hoping to find the most effective herbal medicine to reduce the hepatotoxicity. According to results of biochemical and histological tests, PM could induce the idiosyncratic hepatotoxicity of rats which presented modest inflammation triggered by non-injurious dose of lipopolysaccharide (LPS). We also found that the combined use of Poria and PM in the ratio of 1:2 could significantly ameliorate the PM/LPS-induced liver injury and systemic inflammation. Furthermore, UPLC/QTOF-MS-based metabolomics was performed to identify possible biomarkers and underlying biological pathways. Ten metabolites were expressed differentially among LPS, PM/LPS, and detoxification-treated groups in terms of PCA and OPLS-DA analysis, which could be potential biomarkers. MetaboAnalyst and pathway enrichment analysis revealed that alterations of these metabolites were primarily involved in three pathways: arginine and proline metabolism, primary bile acid biosynthesis and sphingolipid metabolism. This research provides systematic experimental evidences for the hepatoprotective effect of Poria against PM/LPS-induced liver injury for the first time. And these findings may help better understand the underlying mechanisms of pathophysiologic changes in PM/LPS-induced liver injury.

[The toxic and protective effects of Polygonum multiflorum on normal and liver injured rats based on the symptom-based prescription theory].

The dosage-efficacy/toxicity relationship of the 50% alcohol extracts of Polygonum multiflorum was comparatively investigated on either normal or CCl4-induced chronic liver injury rats, by determining the general condition, serum biochemical indices and liver histopathology, coupled with the factor analysis. The dosages were 10 and 20 g raw materials per kg body weight. Compared with the normal control group, the normal high dose group showed significant increases of the serum alanine transaminase (ALT), total bilirubin (TBIL), high mobility group box 1 (HMGB-1) and interleukin-1ß (IL-1ß) (P < 0.05 or P < 0.01), as well the frequent incidences of inflammatory cell infiltration, hepatic sinus enlargement and fiber stripes formation in histopathological sections. Compared with the model control group, the model low dose group showed significant declines of serum ALT, aspartate transaminase (AST) and total bile acid (TBA) (P < 0.05), as well the alleviation of vacuoles of hepatocytes, but no amelioration of the inflammatory cell infiltration and fibrous tissue hyperplasia; moreover, the model high dose group showed significant degeneration declines of serum HMGB-1, tumor necrosis factor-α (TNF-α) and IL-1ß (P < 0.05, P < 0.01), as well the evident alleviation of vacuoles degeneration of hepatocytes, inflammatory cells infiltration and fibrosis degree. The factor analysis showed that the low dosage treatment had almost neither injuring effect on the normal rats nor protective effect on the model rats; while the high dosage treatment showed observable injuring effect on the normal rats, expressed by the significant increases of the factor-1 (HMGB-1, TNF-α and IL-1ß as the main contributors) and factor-2 (TBIL, ALT and TBA as the main contributors) relative to the normal control group. The liver protective effect of the high dosage treatment could be observed with the significant reduction of the factor-1, indicating the effective alleviation of the expression of inflammatory cytokines. In conclusion, it could illustrated the phenomenon of symptom-based prescription theory of Polygonum multiflorum on rat livers: the high dosage of the herb had either an injuring effect on normal rats, or a therapeutic effect on the rats with chronic liver injury.

Screening for biomarkers of liver injury induced by Polygonum multiflorum: a targeted metabolomic study.

Heshouwu (HSW), the dry roots of Polygonum multiflorum, a classical traditional Chinese medicine is used as a tonic for a wide range of conditions, particularly those associated with aging. However, it tends to be taken overdose or long term in these years, which has resulted in liver damage reported in many countries. In this study, the indicative roles of nine bile acids (BAs) were evaluated to offer potential biomarkers for HSW induced liver injury. Nine BAs including cholic acid (CA) and chenodeoxycholic acid (CDCA), taurocholic acid (TCA), glycocholic acid (GCA), glycochenodeoxycholic acid (GCDCA), deoxycholic acid (DCA), glycodeoxycholic acid (GDCA), ursodeoxycholic acid (UDCA), and hyodeoxycholic acid (HDCA) in rat bile and serum were detected by a developed LC-MS method after 42 days treatment. Partial least square-discriminate analysis (PLS-DA) was applied to evaluate the indicative roles of the nine BAs, and metabolism of the nine BAs was summarized. Significant change was observed for the concentrations of nine BAs in treatment groups compared with normal control; In the PLS-DA plots of nine BAs in bile, normal control and raw HSW groups were separately clustered and could be clearly distinguished, GDCA was selected as the distinguished components for raw HSW overdose treatment group. In the PLS-DA plots of nine BAs in serum, the normal control and raw HSW overdose treatment group were separately clustered and could be clearly distinguished, and HDCA was selected as the distinguished components for raw HSW overdose treatment group. The results indicated the perturbation of nine BAs was associated with HSW induced liver injury; GDCA in bile, as well as HDCA in serum could be selected as potential biomarkers for HSW induced liver injury; it also laid the foundation for the further search on the mechanisms of liver injury induced by HSW.

[Comparison of processed and crude Polygoni Multiflori Radix induced rat liver injury and screening for sensitive indicators].

To investigate the difference of liver injury in rats gavaged with crude and processed Polygoni Multiflori Radix. The 75% ethanol extract of crude and processed Polygoni Multiflori Radix (50 g · kg(-1) crude medicine weight/body weight) were continuous oral administered to rats for 6 weeks. Serum biochemical indicators were dynamically detected, the change of liver histopathology was assessed 6 weeks later. Principal component analysis (PCA) was adopted to screen sensitive indicator of the liver damage induced by polygoni multiflori radix. Biochemical tests showed that the crude Polygoni Multiflori Radix group had significant increase of serum ALT, AST, ALP, DBIL and TBIL (P < 0.01 or P < 0.05) and significant decreases of serum IBIL and TBA (P < 0.01 or P < 0.05), while the processed Polygoni Multiflori Radix group showed no obvious changes, compared to the untreated normal group. Histopathologic analysis revealed that crude Polygoni Multiflori Radix group exhibited significant inflammatory cells infiltration in portal area around the blood vessels, tissue destruction and local necrosis of liver cells. There were not obvious pathological changes in processed Polygoni Multiflori Radix group. The results demonstrated that the injury effect of processed Polygoni Multiflori Radix on liver injury of rats was significantly lower than that of unprocessed, and that processing can effectively reduce the hepatotoxicity of Polygoni Multiflori Radix. Traditional transaminase liver function indicators were not sensitive for crude Polygoni Multiflori Radix induced liver damage. The serum content of DBIL and TBIL can reflect the liver damage induced by crude Polygoni Multiflori Radix early and can be sensitive indicators for clinical monitoring the usage of it.