The ethnopharmacology, phytochemistry, pharmacology and toxicology of the genus Erycibe (Convolvulaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Erycibe belongs to the Convolvulaceae family that contains approximately 70 species mainly distributed from tropical and subtropical Asia to north of Australia. Several Erycibe species are traditionally used in folk medicine for the treatment of various ailments, including rheumatic arthralgia, primary glaucoma, hepatopathies, and infectious and malignant diseases.

AIM OF THE REVIEW

This review aims to summarize comprehensive and updated information on traditional medicinal uses, phytochemistry, pharmacology, and toxicology of Erycibe species to provide a reference for the further research and application of the Erycibe genus.

MATERIALS AND METHODS

The scientific and extensive literatures between 1975 and 2020 were systematically gathered from scientific databases such as SciFinder Scholar, Science Direct, Web of Science, PubMed, Google Scholar, Scopus, Springer Link and China National Knowledge Infrastructure (CNKI), as well as Chinese herbal classic books, PhD and MSc theses, and several official websites.

RESULTS

Erycibe species have been used for the treatment of various rheumatoid diseases, glaucoma, a variety of hepatic diseases, infectious diseases and various malignancies in the traditional and local medicine. Since the 1970s, 153 compounds, including coumarins, quinic acid derivatives, flavonoids, alkaloids, lignans, and others have been isolated from five species of the Erycibe genus. Pharmacological studies have shown that these extracts and compounds from the Erycibe genus have extensive activities consistent with the traditional and local applications, such as anti-glaucoma, anti-arthritic, hepatoprotective and anti-cancer activities, as well as anti-inflammatory, anti-respiratory syncytial virus (RSV), and neuroprotective properties.

CONCLUSIONS

Although there are extensive data on the genus Erycibe, certain specific gaps still exist. For herbal preparations containing Erycibe species, clinical toxicological investigation is required for the safety of these herbal preparation therapies, as well as further investigations on pharmacokinetics and bioavailability for guideline for clinical application. Furthermore, more detailed pharmacological, toxicological and clinical researches are needed to assess the alternatives to Erycibe species. Systematic and comprehensive pre-clinical studies are similarly required to estimate the possibility of extracts and compounds from the genus Erycibe with bioactivity developing into new drugs.

A Comprehensive Review of Natural Products against Liver Fibrosis: Flavonoids, Quinones, Lignans, Phenols, and Acids

Liver fibrosis resulting from continuous long-term hepatic damage represents a heavy burden worldwide. Liver fibrosis is recognized as a complicated pathogenic mechanism with extracellular matrix (ECM) accumulation and hepatic stellate cell (HSC) activation. A series of drugs demonstrate significant antifibrotic activity in vitro and in vivo. No specific agents with ideally clinical efficacy for liver fibrosis treatment have been developed. In this review, we summarized the antifibrotic effects and molecular mechanisms of 29 kinds of common natural products. The mechanism of these compounds is correlated with anti-inflammatory, antiapoptotic, and antifibrotic activities. Moreover, parenchymal hepatic cell survival, HSC deactivation, and ECM degradation by interfering with multiple targets and signaling pathways are also involved in the antifibrotic effects of these compounds. However, there remain two bottlenecks for clinical breakthroughs. The low bioavailability of natural products should be improved, and the combined application of two or more compounds should be investigated for more prominent pharmacological effects. In summary, exploration on natural products against liver fibrosis is becoming increasingly extensive. Therefore, natural products are potential resources for the development of agents to treat liver fibrosis.

Efficient drug and gene delivery to liver fibrosis: rationale, recent advances, and perspectives

Liver fibrosis results from chronic damages together with an accumulation of extracellular matrix, and no specific medical therapy is approved for that until now. Due to liver metabolic capacity for drugs, the fragility of drugs, and the presence of insurmountable physiological obstacles in the way of targeting, the development of efficient drug delivery systems for anti-fibrotics seems vital. We have explored articles with a different perspective on liver fibrosis over the two decades, then collected and summarized the information by providing corresponding in vitro and in vivo cases. We have discussed the mechanism of hepatic fibrogenesis with different ways of fibrosis induction in animals. Furthermore, the critical chemical and herbal anti-fibrotics, biological molecules such as micro-RNAs, siRNAs, and growth factors, which can affect cell division and differentiation, are mentioned. Likewise, drug and gene delivery and therapeutic systems on in vitro and in vivo models are summarized in the data tables. This review article enlightens recent advances in emerging drugs and nanocarriers and represents perspectives on targeting strategies employed in liver fibrosis treatment.

[Role of PPAR-γ-regulated autophagy in genistein-induced inhibition of hepatic stellate cell activation]

OBJECTIVE

To investigate the inhibitory effect of genistein on activation of hepatic stellate cells (HSCs) in vitro and the role of the autophagy pathway regulated by PPAR-γ in mediating this effect.

METHODS

Cultured HSC-T6 cells were exposed to different concentrations of genistein for 48 h, and HSC activation was verified by detecting the expressions of -SMA and 1(I) collagen; autophagy activation in the cells was determined by detecting the expressions of LC3-II and p62 using Western blotting. The autophagy inhibitor 3-MA was used to confirm the role of autophagy in genistein-induced inhibition of HSC activation. A PPAR-γ inhibitor was used to explore the role of PPAR-γ in activating autophagy in the HSCs.

RESULTS

Genistein at concentrations of 5 and 50 μmol/L significantly inhibited the expressions of -SMA and 1(I) collagen (P < 0.05), markedly upregulated the expressions of PPAR-γ and the autophagy-related protein LC3-II (P < 0.05) and significantly down-regulated the expression of the ubiqutin-binding protein p62 (P < 0.05) in HSC-T6 cells. The cells pretreated with 3-MA prior to genistein treatment showed significantly increased protein expressions of -SMA and 1(I) collagen compared with the cells treated with genistein only (P < 0.05). Treatment with the PPAR-γ inhibitor obviously lowered the expression of LC3-II and enhanced the expression p62 in genistein-treated HSC-T6 cells, suggesting the activation of the autophagy pathway.

CONCLUSIONS

PPAR-γ- regulated autophagy plays an important role in mediating genistein-induced inhibition of HSC activation in vitro.

Vascular endothelial growth factor C treatment for mouse hind limb lymphatic revascularization

Spontaneous lymphatic revascularization is a challenge and the establishment of new therapeutic strategies may improve life quality for patients suffering from lymphatic disorders. This study was designed to verify if VEGFC treatment improves lymphatic vascularization in a time‐dependent manner in mouse hindlimb (HL) after resection of the inguinal lymph node. Lymphatic vascular density (Vv) and length (Lv) were evaluated by stereology after immunohistochemistry. The control Group (CG) was not manipulated but received saline instead of VEGFC treatment. The surgery Group (SG) had the left inguinal lymph node resected but did not received VEGFC treatment. VEGFC Treated Group (TG) had the node resected and received VEGFC treatment. VEGFC and VEGFR3 local expression were assessed by qPCR. There was an effect of time over Vv and Lv in the SG and significant difference between CG and SG in the regions studied (proximal, medium and distal regions) of the left HL (LHL). The Lv showed significant difference between CG and SG only in the medium region. The Vv and the Lv for TG were higher than the other groups. VEGFC and VEGFR3 gene expression presented time effect in all regions of the LHL for SG and TG. Both VEGFC and VEGFR3 gene expression presented significant difference between CG and SG, between SG and TG and between CG and TG. This study showed significant decrease in lymphatic vascularization in the left hindlimb of mice after surgical removal of the inguinal lymph node and adjacent lymphatic vessels. Exogenous VEGFC could recover lymphatic vascularization through stimulating neolymphangiogenesis.

Genistein Improves Liver Damage in Male Mice Exposed to Morphine

Background:

Morphine is commonly used to treat severe pain. This substance is significantly metabolized in the liver and causes disturbing effects. Genistein is an isoflavone and has antioxidant properties. The aim of this study was to evaluate the effects of genistein against morphine damages on mouse liver.

Methods:

Between May 2017 and March 2018, 48 male mice were divided into six groups (n = 8 in each group). Various doses of genistein (25 and 50 mg/kg) and morphine plus genistein (25 and 50 mg/kg) were administered intraperitoneally to 48 male mice for 20 consequent days. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), serum nitric oxide (NO) levels, liver weight, and the diameter of hepatocytes and central hepatic vein were studied and compared using one-way analysis of variance.

Results:

Morphine administration significantly increased the mean diameter of the central hepatic vein (22.76 ± 1.9 μm vs. 15.04 ± 0.60 μm, χ² = 21.814, P = 0.001) and hepatocytes (3.03 ± 0.10 μm vs. 1.10 ± 0.05 μm, χ² = 9.873, P = 0.001) respectively, blood serum NO level (38.00% ± 2.09% vs. 18.72% ± 4.40%, χ² = 20.404, P < 0.001), liver enzyme level (AST: 111.80 ± 5.10 ng/ml vs. 81.93 ± 2.20 ng/ml, χ² = 32.201, P < 0.0001; ALT: 45.14 ± 4.10 ng/ml vs. 35.49 ± 2.50 ng/ml, χ² = 18.203, P < 0.0001; and ALP: 3.28 ± 0.20 ng/ml vs. 2.14 ± 0.10, χ² = 5.04, P < 0.0001, respectively), and decreased liver weight (18.50 ± 0.90 g vs. 27.15 ± 0.50 g, χ² = 22.415, P = 0.001) compared to saline group (0.535–0.750, P < 0.0001). However, administration of genistein plus morphine significantly enhanced liver weight (25 mg/kg: 21.15 ± 2.13 g vs. 18.50 ± 0.90 g, χ² = 19.251, P < 0.0001; 50 mg/kg: 21.20 ± 1.00 g vs. 18.5 ± 0.9 g, χ² = 19.502, P < 0.0001, respectively) and reduced the mean diameter of hepatocyte (25 mg/kg: 2.17 ± 0.30 μm vs. 3.03 ± 0.10 μm, χ² = 22.780, P = 0.001; 50 mg/kg: 2.01 ± 0.20 μm vs. 3.03 ± 0.10 μm χ² = 7.120, P = 0.001, respectively), central hepatic vein (25 mg/kg: 19.53 ± 1.00 μm vs. 22.76 ± 1.90 μm, χ² = 20.681, P = 0.001; 50 mg/kg: 19.44 ± 1.20 μm vs. 22.76 ± 1.90 μm, χ² = 18.451, P = 0.001, respectively), AST (25 mg/kg: 95.40 ± 5.20 ng/ml vs. 111.80 ± 5.010 ng/ml, P < 0.0001; 50 mg/kg: 90.78 ± 6.00 ng/ml vs. 111.80 ± 5.10 ng/ml, χ² = 17.112, P < 0.0001, respectively), ALT (25 mg/kg: 35.78 ± 5.01 ng/ml vs. 45.14 ± 4.10 ng/ml, χ² = 15.320, P < 0.0001; 50 mg/kg: 33.78 ± 2.60 ng/ml vs. 45.14 ± 4.10 ng/ml, χ² = 14.023, P < 0.0001, respectively), ALP (25 mg/kg: 2.35 ± 0.30 ng/ml vs. 3.28 ± 0.20 ng/ml, χ² = 4.101, P < 0.0001; 50 mg/kg: 2.34 ± 0.10 ng/ml vs. 3.28 ± 0.20 ng/ml, χ² = 2.033, P < 0.0001, respectively), and NO levels (25 mg/kg: 25.92% ± 2.30% vs. 38% ± 2.09%, χ² = 17.103, P < 0.0001; 50 mg/kg: 24.74% ± 4.10% vs. 38% ± 2.09%, χ² = 25.050, P = 0.001, respectively) compared to morphine group.

Conclusion:

It seems that genistein administration might improve liver damages induced by morphine in mice.

Anti-fibrosis activity of combination therapy with epigallocatechin gallate, taurine and genistein by regulating glycolysis, gluconeogenesis, and ribosomal and lysosomal signaling pathways in HSC-T6 cells

A previous study by our group indicated that combined treatment with taurine, epigallocatechin gallate (EGCG) and genistein protects against liver fibrosis. The aim of the present study was to elucidate the antifibrotic mechanism of this combination treatment using isobaric tag for relative and absolute quantification (iTRAQ)-based proteomics in an activated rat hepatic stellate cell (HSC) line. In the present study, HSC-T6 cells were incubated with taurine, EGCG and genistein, and cellular proteins were extracted and processed for iTRAQ labeling. Quantification and identification of proteins was performed using two-dimensional liquid chromatography coupled with tandem mass spectrometry. Proteomic analysis indicated that the expression of 166 proteins were significantly altered in response to combination treatment with taurine, EGCG and genistein. A total 76 of these proteins were upregulated and 90 were downregulated. Differentially expressed proteins were grouped according to their association with specific Kyoto Encyclopedia of Genes and Genomes pathways. The results indicated that the differentially expressed proteins hexokinase-2 and lysosome-associated membrane glycoprotein 1 were associated with glycolysis, gluconeogenesis and lysosome signaling pathways. The expression of these proteins was validated using western blot analysis; the expression of hexokinase-2 was significantly decreased and the expression of lysosome-associated membrane glycoprotein 1 was significantly increased in HSC-T6 cells treated with taurine, EGCG and genistein compared with the control, respectively (P<0.05). These results were in accordance with the changes in protein expression identified using the iTRAQ approach. Therefore, the antifibrotic effect of combined therapy with taurine, EGCG and genistein may be associated with the activation of several pathways in HSCs, including glycolysis, gluconeogenesis, and the ribosome and lysosome signaling pathways. The differentially expressed proteins identified in the current study may be useful for treatment of liver fibrosis in the future.

Txn1, Ctsd and Cdk4 are key proteins of combination therapy with taurine, epigallocatechin gallate and genistein against liver fibrosis in rats

The anti-fibrotic mechanism of combination therapy with taurine, epigallocatechin gallate and genistein was studied from the perspective of serum proteomics in our previous work. In order to further investigate and systematically analyse other possible therapeutic mechanism of combination therapy against liver fibrosis, isobaric tags for relative and absolute quantification (iTRAQ) proteomic analysis was applied to study the protein profile changes in liver tissue of carbon tetrachloride-induced liver fibrosis rats after combination therapy. A total of 115 differentially expressed proteins containing 84 up-regulated and 31 down-regulated proteins in response to combination therapy were identified. Three differentially expressed proteins (Txn1, Ctsd and Cdk4) involved in antioxidant defense system and the activation and proliferation of hepatic stellate cell were selected for further validation by western blot and real-time PCR analysis. Our study highlight the importance of differentially expressed proteins Txn1, Ctsd and Cdk4 against liver fibrosis, which may provide a more precise and comprehensive perspective for clarifying the roles of combination therapy as a potential agent for treatment of liver fibrosis.

Quantitative succinylome analysis in the liver of non-alcoholic fatty liver disease rat model

Background

Non-alcoholic fatty liver disease (NAFLD) is a clinical frequent disease. However, its pathogenesis still needs further study, especially the mechanism at the molecular level. The recent identified novel protein post-translational modification, lysine succinylation was reported involved in diverse metabolism and cellular processes. In this study, we performed the quantitative succinylome analysis in the liver of NAFLD model to elucidate the regulatory role of lysine succinylation in NAFLD progression.

Methods

Firstly, experimental model of NAFLD was induced by carbon tetrachloride injection and supplementary high-lipid and low-protein diet. Then series histochemical and biochemical variables were determined. For the quantitative succinylome analysis, tandem mass tags (TMT)-labeling, highly sensitive immune-affinity purification, liquid chromatography-tandem mass spectrometry techniques were applied. Bioinformatics analysis including gene ontology annotation based classification; Wolfpsort based subcellular prediction; function enrichment; protein-protein interaction network construction and conserved succinylation site motifs extraction were performed to decipher the differentially changed succinylated proteins and sites and p-value < 0.05 was selected as threshold.

Results

Totally, 815 succinylation sites on 407 proteins were identified, of which 243 succinylation acetylation sites on 178 proteins showed changed succinylation level with the threshold fold change > 1.5. Theses differentially changed succinylated proteins were involved in diverse metabolism pathways and cellular processes including carbon metabolism, amino acid metabolism, fat acid metabolism, binding and catalyzing, anti-oxidation and xenobiotics metabolism. Besides, these differentially changed succinylated proteins were prominently localized to cytoplasm and mitochondria. Moreover, 8 conserved succinylation site motifs were extracted around the succinylation sites.

Conclusions

Protein succinylation was an extensive post-translation modification in rat. The changed succinylation level in diverse proteins may disturb multiple metabolism pathways and promote non-alcoholic fatty liver disease development. This study provided a basis for further characterization of the pathophysiological role of lysine succinylation in NAFLD progression, which laid a foundation for the innovation of novel NAFLD drugs and therapies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12953-016-0092-y) contains supplementary material, which is available to authorized users.

iTRAQ-based proteomic analysis of combination therapy with taurine, epigallocatechin gallate, and genistein on carbon tetrachloride-induced liver fibrosis in rats

Combination therapy with taurine, epigallocatechin gallate, and genistein was effective in alleviating the progression of liver fibrosis in our previous study. To better understand the anti-fibrotic mechanisms of combination therapy, an iTRAQ-based proteomics approach was used to study the expression profiles of proteins in carbon tetrachloride-induced liver fibrosis rats following combination therapy. The anti-fibrotic effects of combination therapy were assessed directly by liver histology, and indirectly by measurement of serum biochemical markers and antioxidant enzymes. The results showed that combination therapy could significantly improve the liver function, as indicated by decreasing levels of alanine aminotransferase (ALT), aspartate transaminase (AST), transforming growth factor-β1 (TGF-β1), and collagen I, increasing levels of total antioxidative capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), and reducing the pathological tissue damage. A total of 89 differential expressed proteins in response to combination therapy were identified by iTRAQ, which were interacted with each other and involved in different biological processes and pathways. Four differentially expressed proteins (Tpi1, Txn1, Fgb, and F7) involved in antioxidant defense system, glycolysis pathway and coagulation cascade pathway were validated by enzyme-linked immunosorbent assay. Our work provided valuable insights into the molecular mechanism of combination therapy against liver fibrosis, and the identified targets may be useful for treatment of liver fibrosis in future.

Combined taurine, epigallocatechin gallate and genistein therapy reduces HSC-T6 cell proliferation and modulates the expression of fibrogenic factors

Hepatic fibrogenesis involves the activation of hepatic stellate cells (HSCs), which synthesize excess extracellular matrix and contribute to the development of liver fibrosis. In a prior study we tested the effect of combined treatment with taurine, epigallocatechin gallate and genistein on the development of alcohol-induced liver fibrosis in vitro. In this study, the biological activity of the combination of these molecules was assessed by measuring its effect on cell proliferation, fibrosis-related gene expression, and proteomic expression profiling in the activated HSC cell line, HSC-T6. HSC-T6 cells were incubated with different concentrations of the drug combination taurine, epigallocatechin gallate and genistein. Cell proliferation was evaluated by MTT assay. Transforming growth factor β1 (TGF-β1), collagen type I (Col-I), matrix metalloproteinase-2 (MMP-2), and tissue inhibitor of metalloproteinases 1 and 2 (TIMP-1 and TIMP-2) mRNA were analyzed by semi-quantitative reverse-transcription PCR. Proteomic profiling of HSC-T6 cells was also performed by SELDI-TOF-MS. Combined drug treatment significantly inhibited cell proliferation and TGF-β1, Col-I, TIMP-1 and TIMP-2 mRNA expression in activated HSC-T6 cells, while the expression of MMP-2 mRNA increased. A total of 176 protein m/z peaks were identified. The intensities of 10 protein peaks were downregulated and two protein peaks were upregulated in HSC-T6 cells after combined drug treatment. In conclusion, combined drug treatment with taurine, epigallocatechin gallate and genistein can inhibit HSC proliferation, and impact fibrosis-related gene and protein expression. The antifibrotic effects of this drug combination may be due to its effects on the expression of fibrogenic genes.