Polysaccharide peptides from Coriolus versicolor competitively inhibit model cytochrome P450 enzyme probe substrates metabolism in human liver microsomes

Polysaccharide Peptide Treatment Eliminates Strawberry Viruses and Promotes Strawberry Plant Growth and Rooting in Tissue Culture Media

Based on our previous finding that polysaccharide peptide (PSP) has substantial antiviral activity, we cultured strawberry plants infected with strawberry mild yellow edge virus (SMYEV) or strawberry vein banding virus (SVBV) in Murashige and Skoog (MS) media supplemented with PSP to test its ability to eliminate these viruses. PSP not only improved the elimination of SMYEV and SVBV but also promoted the growth and rooting of strawberry plants in tissue culture. On the 45th day, the average height of the 'Ningyu' strawberry plants in the 1-mg/ml PSP treatment group was 1.91 cm, whereas that of the plants in the control group was 1.51 cm. After the same time point, the number of new leaves on the tissue culture media supplemented with 1 mg/ml and 500 μg/ml of PSP and without PSP were 4.92, 4.41, and 3.53, respectively. PSP also promoted strawberry rooting and significantly increased both the length and number of roots. In addition, after treatment with the 1-mg/ml PSP treatment in tissue culture for 45 days followed by meristem-shoot-tip culture, the elimination rates of SMYEV and SVBV in regenerated 'Ningyu' strawberry plants ranged from 60 to 100%. This study investigated the use of the antiviral agent PSP for virus elimination. PSP has a low production cost and thus has great application potential for virus elimination in crop plants.

Mechanistic Study of Novel Dipeptidyl Peptidase IV Inhibitory Peptides from Goat's Milk Based on Peptidomics and In Silico Analysis

Two novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (YPF and LLLP) were discovered from goat milk protein by peptidomics, in silico analysis, and in vitro assessment. A total of 698 peptides (<23 AA) were successfully identified by LC-MS/MS from goat milk hydrolysates (hydrolyzed by papaian plus proteinase K). Then, 105 potential DPP-IV inhibitory peptides were screened using PeptideRanker, the ToxinPred tool, Libdock, iDPPIV-SCM, and sequence characteristics. After ADME, physicochemical property evaluation, and a literature search, 12 candidates were efficiently selected and synthesized in vitro for functional validation. Two peptides (YPF and LLLP) were found to exert relatively high in vitro chemical system (IC50 = 368.54 ± 12.97 μM and 213.99 ± 0.64 μM) and in situ (IC50 = 159.46 ± 17.40 μM and 154.96 ± 8.41 μM) DPP-IV inhibitory capacities, and their inhibitory mechanisms were further explored by molecular docking. Our study showed that the formation of strong non-bonding interactions with the core residues from the pocket of DPP-IV (such as ARG358, PHE357, GLU205, TYR662, TYR547, and TYR666) might primarily account for the DPP-IV inhibitory activity of two identified peptides. Overall, the two novel DPP-IV inhibitory peptides rapidly identified in this study can be used as functional food ingredients for the control of diabetes.

Effects of Cold Plasma Pretreatment on the Synthesis of Polysaccharide from Pleurotus ostreatus

Fungal polysaccharides have attracted wide attention because of their medical pharmaceutical and health care value. So far, many efforts have been made in strain improvement to produce polysaccharides on a large scale at low cost. Here, a novel cold plasma-induced strain improvement technology was employed to pretreat Pleurotus ostreatus CGMCC 5.374 by radio-frequency (RF) low-vacuum cold plasma (LVCP) for the purpose of obtaining a high-yield polysaccharide strain. The optimum pretreatment conditions including discharge power, treatment time, and working pressure were determined by single factor and orthogonal experiment in succession. Furthermore, transcriptome analysis was conducted to study the effects of RF-LVCP on cell metabolism and proliferation. Results showed that under the optimal condition of discharge power of 130 W, treatment time of 25 s and working pressure of 140 Pa, polysaccharide content in mycelium was increased by 3.16% after 6 days in comparison to the original strain. Transcriptome analysis showed that RF-LVCP is helpful for specific gene transcription profiles, Gene Ontology (GO) and KEGG pathways, of which the differentially expressed genes (DEGs) were mainly involve with the up-regulation of polysaccharide transport, physiology, synthesis and metabolism, as well as the down-regulation of polysaccharide hydrolysis and macromolecular degradation.

Preclinical pharmacokinetics-related pharmacological effects of orally administered polysaccharides from traditional Chinese medicines: A review

Polysaccharides (TCMPs) derived from traditional Chinese medicines (TCMs), such as Ganoderma lucidum, Astragalus membranaceus, Lycium barbarum, and Panax ginseng, are considered to be the main active constituents in TCMs. However, the significant pharmacological effects of orally administered TCMPs do not align well with their poor pharmacokinetics. This article aims to review the literature published mainly from 2010 to 2022, focusing on the relationship between pharmacokinetics and pharmacological effects. It has been found that unabsorbed TCMPs can exert local pharmacological effects in the gut, including anti-inflammation, anti-oxidation, regulation of intestinal flora, modulation of intestinal immunity, and maintenance of intestinal barrier integrity. Unabsorbed TCMPs can also produce systemic pharmacological effects, such as anti-tumor activity and immune system modulation, by regulating intestinal flora and immunity. Conversely, some TCMPs can be absorbed and distributed to various tissues, especially the liver, where they exhibit tissue-protecting effects against inflammation and oxidative stress-induced damage and improve glucose and lipid metabolism. In future studies, it is important to improve quality control and experimental design. Furthermore, research on enhancing the oral bioavailability of TCMPs, exploring the activity of TCMP metabolites, investigating pharmacokinetic interactions between TCMPs and oral drugs, and developing oral drug delivery systems using TCMPs holds great significance.

Wild Mushrooms: A Hidden Treasure of Novel Bioactive Compounds

Secondary metabolites are hidden gems in mushrooms. Understanding these secondary metabolites' biological and pharmacological effects can be aided by identifying them. The purpose of this work was to profile the mycochemical components of the extracts of Auricularia auricula judae, Microporus xanthopus, Termitomyces umkowaani, Trametes elegans, and Trametes versicolor to comprehend their biological and pharmacological capabilities. Mushroom samples were collected from Kenya's Arabuko-Sokoke and Kakamega National Reserved Forests and identified using morphological and molecular techniques. Chloroform, 70% ethanol, and hot water solvents were used to extract the mycochemical components. Gas chromatography mass spectrometry (GC-MS) was used to analyze the chloroform, 70% ethanol, and hot water extracts of all the species examined. A total of 51 compounds were isolated from all extracts and classified as carboxylic acids, esters, phenols, fatty acids, alcohol, epoxides, aldehydes, fatty aldehydes, isoprenoid lipids, and steroids. Tetracosamethyl-cyclododecasiloxane (18.90%), oleic acid (72.90%), phenol, 2, 6-bis (1, 1-dimethylethyl)-4-methyl-, and methylcarbamate (26.56%) were all found in high concentrations in A. auricular judae, M. xanthopus, T. umkowaani, T. elegans, and T. versicolor, respectively. Fatty acids make up the majority of the compounds isolated from the T. elegans chloroform extract and the T. umkowaani 70% ethanol extract, respectively. Particularly, these fatty acids play crucial roles in the anti-inflammatory, hypocholesterolemic, anticancer, and antibiofilm formation activities. These bioactive elements indicate that the extracts of five wild mushrooms may be reliable sources of secondary metabolites for therapeutic development. Therefore, additional research is required to comprehend the usefulness of these chemicals in many functional areas and to improve the present understanding of macrofungi.

ADMET profiling and molecular docking of potential antimicrobial peptides previously isolated from African catfish, Clarias gariepinus

Amidst rising cases of antimicrobial resistance, antimicrobial peptides (AMPs) are regarded as a promising alternative to traditional antibiotics. Even so, poor pharmacokinetic profiles of certain AMPs impede their utility necessitating, a careful assessment of potential AMPs' absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties during novel lead exploration. Accordingly, the present study utilized ADMET scores to profile seven previously isolated African catfish antimicrobial peptides (ACAPs). After profiling, the peptides were docked against approved bacterial protein targets to gain insight into their possible mode of action. Promising ACAPs were then chemically synthesized, and their antibacterial activity was validated in vitro utilizing the broth dilution method. All seven examined antimicrobial peptides passed the ADMET screening, with two (ACAP-IV and ACAP-V) exhibiting the best ADMET profile scores. The ACAP-V had a higher average binding energy (-8.47 kcal/mol) and average global energy (-70.78 kcal/mol) compared to ACAP-IV (-7.60 kcal/mol and -57.53 kcal/mol), with the potential to penetrate and disrupt bacterial cell membrane (PDB Id: 2w6d). Conversely, ACAP-IV peptide had higher antibacterial activity against E. coli and S. aureus (Minimum Inhibitory Concentration, 520.7 ± 104.3 μg/ml and 1666.7 ± 416.7 μg/ml, respectively) compared to ACAP-V. Collectively, the two antimicrobial peptides (ACAP-IV and ACAP-V) are potential novel leads for the food, cosmetic and pharmaceutical industries. Future research is recommended to optimize the expression of such peptides in biological systems for extended evaluation.

Coriolus (Trametes) versicolor mushroom to reduce adverse effects from chemotherapy or radiotherapy in people with colorectal cancer

BACKGROUND

Radiotherapy and chemotherapy are used to improve survival in colorectal cancer but adverse effects can be a problem. Severe adverse effects may result in dose reduction or cessation of treatment, which have an impact on survival. Coriolus versicolor (Trametes versicolor or 'Turkey Tail') mushroom and its extracts have been used by cancer patients to help with adverse effects.

OBJECTIVES

To assess the effects of adjunctive Coriolus versicolor (Trametes versicolor) and its extracts on adverse effects and on survival during colorectal cancer treatment (chemotherapy and radiotherapy) compared with no adjunctive treatment.

SEARCH METHODS

We searched databases including CENTRAL, MEDLINE, Embase, AMED and CINAHL, Chinese and Japanese databases, and trials registers to 12th April 2022 without restriction of language or publication status. We screened reference lists and attempted to contact researchers in the field to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) investigating the efficacy and safety of Coriolus versicolor and its extracts in adult participants with a confirmed diagnosis of colorectal cancer, in addition to conventional treatment. Interventions included any preparation of Coriolus versicolor (raw, decoction, capsule, tablet, tincture, extract, injection), any part of the fungus (cap, stem, mycelium or whole), in any dose or regimen. Outcomes included adverse events rates, survival, disease progression and recurrence, response rates and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and selected studies, extracted outcome data, and assessed risk of bias. We evaluated the overall certainty of evidence using the GRADE approach.

MAIN RESULTS

We included seven parallel RCTs (1569 participants). Six studies (1516 participants) were conducted in Japan and one study (53 participants) in China. Studies included both male and female participants with colorectal cancer (five studies), colon cancer (one study) or rectal cancer (one study). Participants were diagnosed with cancer ranging from stage II to stage IV. Coriolus was used in the form of an extract in all seven studies and was generally used after curative resection, although in one study it was used preoperatively. Duration of treatment with the extract varied between four weeks and three years. Chemotherapeutic regimens in six studies consisted of an oral fluoropyrimidine which was preceded by weekly intravenous 5-Fluorouracil (5-FU) in one study, by mitomycin C in two studies, and which was combined with folinic acid (Leucovorin) in two studies and with radiotherapy preoperatively in one study. XELOX (oxaliplatin intravenous infusion and capecitabine) was used in the remaining study. We found very low-certainty evidence of little to no effect of adjunctive treatment with Coriolus (in the form of an extract, polysaccharide-Krestin, PSK) on withdrawal from treatment due to adverse events  (risk ratio (RR) 1.03, 95% confidence interval (CI) 0.45 to 2.34; 703 participants; 3 studies;). We are uncertain whether adjunctive Coriolus versicolor and its extracts compared to usual care alone resulted in a difference in adverse events including neutropenia (RR 0.41, 95% CI 0.24 to 0.71; 133 participants; 3 studies; very low certainty), oral cavity disorders such as oral dryness and mucositis (RR 0.37, 95% CI 0.13 to 1.03; 1022 participants; 5 studies; very low certainty), nausea (RR 0.73, 95% CI 0.44 to 1.22; 969 participants; 4 studies; very low certainty), diarrhoea (RR 0.77, 95% CI 0.32 to 1.86; 1022 participants; 5 studies; very low certainty), and fatigue (RR 0.76; 95% CI 0.33 to 1.78; 133 participants; 3 studies; very low certainty). We found low-certainty evidence of a small effect of adjunctive Coriolus on improved survival at five years compared with no adjunctive care (RR 1.08, 95% CI 1.01 to 1.15; 1094 participants; 3 studies; number needed to benefit (NNTB) = 16 (95% Cl 9 to 70). The effect at earlier time points was unclear.

AUTHORS' CONCLUSIONS

Due to the very low certainty of evidence, we were uncertain about the effect of adjunctive Coriolus (in the form of an extract PSK) on adverse events resulting from conventional chemotherapy for colorectal cancer. This includes effects on withdrawal of treatment due to adverse events and on specific adverse outcomes such as neutropenia and nausea. The uncertainty in the evidence also means that it was unclear whether any adverse events were due to the chemotherapy or to the extract itself. While there was low-certainty evidence of a small effect on overall survival at five years, the influence of reduced adverse effects on this could not be determined. In addition, chemotherapy regimens used in assessing this outcome do not reflect current preferred practice.

Bioactivity of Biomass and Crude Exopolysaccharides Obtained by Controlled Submerged Cultivation of Medicinal Mushroom Trametes versicolor

The aim of this study is to characterize the bioactivity of mycelial biomass and crude exopolysaccharides (EPS) produced by Trametes versicolor NBIMCC 8939 and to reveal its nutraceutical potential. The EPS (1.58 g/L) were isolated from a culture broth. The macrofungal biomass was rich in protein, insoluble dietary fibers and glucans. The amino acid composition of the biomass was analyzed and 18 amino acids were detected. Three mycelial biomass extracts were prepared and the highest total polyphenol content (16.11 ± 0.14 mg GAE/g DW) and the total flavonoid content (5.15 ± 0.03 mg QE/g DW) were found in the water extract. The results indicated that the obtained EPS were heteropolysaccharides with glucose as the main building monosaccharide and minor amounts of mannose, xylose, galactose, fucose and glucuronic acid. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the complex structure of the crude EPS. Five probiotic lactic acid bacteria strains were used for the determination of the prebiotic effect of the crude EPS. The anti-inflammatory potential was tested in vitro using cell line HT-29. The significant decrease of IL-1 and IL-8 and increase of TGF-beta expression revealed anti-inflammatory potential of the crude exopolysaccharides from T. versicolor.

Polysaccharide Peptide Extract From Coriolus versicolor Increased Tmax of Tamoxifen and Maintained Biochemical Serum Parameters, With No Change in the Metabolism of Tamoxifen in the Rat

Background: Polysaccharide peptide (PSP) extract of Coriolus versicolor (L.) Quél. (1886) (Trametes; Polyporaceae) is increasingly used in cancer to support the immune system. However, its interaction with tamoxifen is unknown.

Aim of the study: To investigate the effect of a PSP extract on the pharmacokinetics, biochemical parameters, and depletion of tamoxifen.

Methods: The pharmacokinetic and biochemical parameters of tamoxifen (20 mg/mL oral single dose and repeated dosing for 12 days) was investigated in female Sprague Dawley rats with or without PSP (340 mg/kg orally for 7 days) (n = 5 per group). Tamoxifen (5 µM) depletion rate with PSP (10–100 μg/mL) was measured in female rat hepatic microsomes in vitro.

Results: Compared to tamoxifen alone, the time to reach maximum concentration (T_max) significantly increased by 228% (4.15 ± 1.15 versus 13.6 ± 2.71 h) in the single tamoxifen dose with PSP and 93% (6 ± 2.17 versus 11.6 ± 0.4 h) in the repeated tamoxifen dosing with PSP (p < 0.05). No significant changes in the area-under-curve and maximum concentration were observed in the single dose and repeated tamoxifen dosing plus PSP compared to tamoxifen alone. Pharmacodynamically, the repeated tamoxifen dosing with PSP maintained 19 out of 23 hepatic, renal and cardiac biochemical serum parameters in rats compared to untreated rats (p > 0.05). PSP extract did not significantly alter in vitro intrinsic clearance of tamoxifen compared to tamoxifen control.

Conclusion: With the increased use of PSP as an adjunct therapy, this study highlights the importance of clinician’s knowledge of its interaction with tamoxifen to avoid compromising clinical actions and enhancing clinical therapy.

Isolation and structure elucidation of polysaccharides from fruiting bodies of mushroom Coriolus versicolor and evaluation of their immunomodulatory effects

Coriolus versicolor is an edible medicinal mushroom in China. Two polysaccharides, named as CVPn and CVPa were separated from the dried fruiting bodies of Coriolus versicolor by water extraction and ethanol precipitation. Their chemical structures were well elucidated with overall consideration of monosaccharide composition, methylation analysis and 1D/2D-NMR spectra data. The bioactivities on RAW 264.7 macrophages cells were evaluated, and further structure-bioactivity relationships were concluded. With molecular weight of 29.7 kDa for CVPn and 50.8 kDa for CVPa, the two isolated polysaccharides were both composed of (l → 4)-β-/(1 → 3)-β-d-glucopyranosyl group as backbone with branches attached at O-6 site. Comparing to CVPn, CVPa with relative high molecular weight and less branches showed significant induction of NO production, obvious augmentation of iNOS and TNF-α mRNA expression level, and phagocytosis on RAW 264.7 cells. These results clarified that CVP polysaccharides with less branches and high molecular weight possessed enhanced immunomodulatory ability, and this finding could be a reference for the utilization of Coriolus versicolor.

In vitro bioactivity, antimicrobial and anti-inflammatory efficacy of modified solvent evaporation assisted Trametes versicolor extract

In the present study, modified solvent evaporation assisted methanolic Trametes versicolor extract was evaluated for its antimicrobial and anti-inflammatory efficacy. Mushroom extract showed significantly (p < 0.05) higher total phenolic content (48.71 mg/g) followed by total flavonoid content (13.13 mg/g), ascorbic acid content (11.03 mg/g), β-carotene content (8.34), and lycopene content (6.85). Fourier transform infrared spectroscopy revealed the functional groups of the observed bioactive compounds, while HPLC chromatogram showed significantly (p < 0.05) higher gallic acid content (45.72 mg/g) as compared to rutin content (12.50 mg/g). Statistically, mushroom extract and artificial antioxidant (BHA) showed a non-significant (p < 0.05) difference in terms of percentage inhibition during DPPH and N₂O₂ scavenging assay. During the time-kill kinetics, the mushroom extract significantly inhibited the growth of S. aureus in comparison with the growth of P.aeruginosa, K. pneumonia, and E.coli. Mushroom extract showed effective anti-inflammatory activity during membrane stabilization (33.71-73.24%) and protein denaturation (23.11-74.56%) assays.

Mushroom extracts and compounds with suppressive action on breast cancer: evidence from studies using cultured cancer cells, tumor-bearing animals, and clinical trials

This article reviews mushrooms with anti-breast cancer activity. The mushrooms covered which are better known include the following: button mushroom Agaricus bisporus, Brazilian mushroom Agaricus blazei, Amauroderma rugosum, stout camphor fungus Antrodia camphorata, Jew's ear (black) fungus or black wood ear fungus Auricularia auricula-judae, reishi mushroom or Lingzhi Ganoderma lucidum, Ganoderma sinense, maitake mushroom or sheep's head mushroom Grifola frondosa, lion's mane mushroom or monkey head mushroom Hericium erinaceum, brown beech mushroom Hypsizigus marmoreus, sulfur polypore mushroom Laetiporus sulphureus, Lentinula edodes (shiitake mushroom), Phellinus linteus (Japanese "meshimakobu," Chinese "song gen," Korean "sanghwang," American "black hoof mushroom"), abalone mushroom Pleurotus abalonus, king oyster mushroom Pleurotus eryngii, oyster mushroom Pleurotus ostreatus, tuckahoe or Fu Ling Poria cocos, and split gill mushroom Schizophyllum commune. Antineoplastic effectiveness in human clinical trials and mechanism of anticancer action have been reported for Antrodia camphorata, Cordyceps sinensis, Coriolus versicolor, Ganoderma lucidum, Grifola frondosa, and Lentinula edodes.

Potential activities and mechanisms of extracellular polysaccharopeptides from fermented Trametes versicolor on regulating glucose homeostasis in insulin-resistant HepG2 cells

Polysaccharides derived from mushrooms have potential to control blood sugar, reduce insulin resistance and prevent diabetic complications. The intracellular polysaccharopeptides of Trametes versicolor (TV) have been used as immunologic and oncologic adjuvants. The aim of this study was to investigate the potential activities and mechanisms of extracellular polysaccharopeptides (ePSP) obtained from TV strain LH-1 on regulating glucose homeostasis. Human hepatoma HepG2 cells incubated with normal glucose (5.5 mM, NG model), high glucose (33 mM, HG model), or high glucose (33 mM) plus high insulin (10⁻⁷ M, HGI model) concentrations were administered with TV LH-1 ePSP (50, 100, and 1000 μg/ml) for 24 hr. Glucose uptake of HepG2 cells, determined by flow cytometry, was significantly decreased in the HG and HGI models with insulin stimulation, suggesting insulin resistance of these cells; however, ePSP reversed this decrease in a dose-dependent manner (one-way ANOVA, p<0.05). In the HG and HGI models, ePSP significantly increased glycogen content, insulin receptor substrate-2 protein and phosphorylated AMP-activated protein kinase (AMPK), as determined by western blot analysis. In addition, ePSP significantly increased glucokinase in the NG and HG models, increased membrane glucose transporter-1 and decreased glycogen synthase kinase-3β in the HGI model, and increased glucose-6-phosphatase in the NG and HGI models (one-way ANOVA, p<0.05). In summary, TV LH-1 ePSP may elevate cellular glucose uptake to regulate glucose homeostasis via the activation of AMPK and glycogen synthesis in an insulin-independent manner. These results suggest that TV LH-1 ePSP may be a nutraceutical with anti-hyperglycemic activity.

Polysaccharide Peptide-Induced Virus Resistance Depends on Ca2+ Influx by Increasing the Salicylic Acid Content and Upregulating the Leucine-Rich Repeat Gene in Arabidopsis thaliana

Plant viral diseases cause severe economic losses in agricultural production. The development of biosource-derived antiviral agents provides an alternative strategy to efficiently control plant viral diseases. We previously reported that the exogenous application of polysaccharide peptide (PSP) exerts significant inhibitive effects on Tobacco mosaic virus infection in Nicotiana tabacum. In this study, we studied in additional detail the mechanism by which PSP can induce virus resistance in Arabidopsis thaliana. We found that PSP significantly induced Ca²⁺ influx and increased the accumulation of hydrogen peroxide and salicylic acid (SA) in the A. thaliana cells. A gene with a toll interleukin 1 receptor-nucleotide binding site-leucine-rich repeat domain (LRR) was obtained by RNA sequencing in combination with the screening of the gene-deletion mutants of A. thaliana. The LRR gene was deleted, and the inductive response of A. thaliana to PSP was significantly attenuated after mutation. After the heterologous overexpression of the LRR gene in N. benthamiana, the SA content and PR1 gene expression in N. benthamiana were significantly increased. Through analyses of the LRR gene expression and the ability of A. thaliana to resist Cucumber mosaic virus following the treatments of PSP and PSP + ethyleneglycol-bis (beta-aminoethylether)-N,N'-tetraacetic acid, it was shown that PSP enhanced the virus resistance of A. thaliana by inducing Ca²⁺ influx and subsequently improving expression of the LRR gene, which further increased the SA content.

Enhancing the Antioxidant Ability of Trametes versicolor Polysaccharopeptides by an Enzymatic Hydrolysis Process

Polysaccharopeptides (PSPs) are among the main bioactive constituents of Trametes versicolor (T. versicolor). The purpose of this research was to investigate the antioxidant activities of enzymatic hydrolysates obtained from T.versicolor polysaccharopeptides by 80 U/mL β-1,3-glucanase (PSPs-EH80). The half-inhibitory concentration (IC₅₀) of PSPs-EH80 in metal chelating assay, ABTS and DPPH radical scavenging test results were 0.83 mg/mL, 0.14 mg/mL and 0.52 mg/mL, respectively, which were lower than that of PSPs-EH 20 U/mL. The molecular weights of the PSPs-EH80 hydrolysates were 300, 190, 140 and 50 kDa, respectively, and the hydrolysis of polysaccharides by β-1,3-glucanase did not change the original functional group. PSPs-EH80 reduced the reactive oxygen species (ROS) content at least twice that of treatment without PSPs-EH80. In addition, an oxidative damage test showed that PSPs-EH80 can improve HaCaT cell survival. According to our results, PSP demonstrates the potential of anti-oxidative damage; besides, enzyme hydrolysis can improve the ability of the PSP.

Modulation of Hepatic Cytochrome P450 Enzymes by Curcumin and its Pharmacokinetic Consequences in Sprague-dawley Rats

Background:

Curcumin (CUR) is a polyphenolic component derived from an herbal remedy and dietary spice turmeric (Curcuma longa).

Objective:

The aim of this study was to investigate inhibitory effects of CUR on in vitro cytochrome P450 (CYP) activity and in vivo pharmacokinetic consequences of single CUR dose in rats.

Materials and Methods:

An in vitro CYP inhibition study in rat liver microsomes (RLM) was conducted using probe substrates for CYPs. Then, an in vivo pharmacokinetics of intravenous buspirone (BUS), a probe substrate for CYP3A, was studied with the concurrent administration of oral CUR in rats.

Results:

In the in vitro CYP inhibition study, CUR inhibited the CYP3A-mediated metabolism of testosterone (TES) with a half maximal inhibitory concentration of 11.0 ± 3.3 μM. However, the impact of a single oral CUR dose on the pharmacokinetics of BUS in rats is limited, showing that CUR cannot function as an inhibitor for CYP3A-mediated drug metabolism in vivo.

Conclusion:

To the best of our knowledge, our results are the first reported data regarding the inhibition of in vitro CYP3A-mediated metabolism of TES and the in vivo impact of a single CUR dose on the pharmacokinetics of BUS in rats. Further study is required to draw a confirmative conclusion on whether CUR can be a clinically relevant CYP3A4 inhibitor.

SUMMARY

CUR can inhibit the in vitro CYP3A-mediated metabolism of TES in RLM. However, the impact of a single oral CUR dose on the pharmacokinetics of BUS in rats is limited, showing that CUR cannot function as an inhibitor for CYP3A-mediated drug metabolism in vivo.

Metabolic interactions of magnolol with cytochrome P450 enzymes: uncompetitive inhibition of CYP1A and competitive inhibition of CYP2C

Magnolol (MAG; 5,5'-diallyl-2,2'-biphenyldiol) is a major bioactive component of Magnolia officinalis. We investigated the metabolic interactions of MAG with hepatic cytochrome P450 monooxygenase (CYP) through in vitro microsomal metabolism study using human (HLM) and rat liver microsomes (RLM). CYP2C and 3A subfamilies were significantly involved in the metabolism of MAG, while CYP1A subfamily was not in HLM and RLM. The relative contribution of phase I enzymes including CYP to the metabolism of MAG was comparable to that of uridine diphosphate glucuronosyltransferase (UGT) in RLM. Moreover, MAG potently inhibited the metabolic activity of CYP1A (IC50 of 1.62 μM) and 2C (IC50 of 5.56 μM), while weakly CYP3A (IC50 of 35.0 μM) in HLM and RLM. By the construction of Dixon plot, the inhibition type of MAG on CYP activity in RLM was determined as follows: uncompetitive inhibitor for CYP1A (Ki of 1.09-12.0 μM); competitive inhibitor for CYP2C (Ki of 10.0-15.2 μM) and 3A (Ki of 93.7-183 μM). Based on the comparison of the current IC50 and Ki values with a previously reported liver concentration (about 13 μM) of MAG after its seven times oral administration at a dose of 50 mg/kg in rats, it is suggested that MAG could show significant inhibition of CYP1A and 2C, but not CYP3A, in the in vivo rat system. These results could lead to further studies in clinically significant metabolism-mediated MAG-drug interactions.

Modulation of Cytochrome P450 Activity by 18β-Glycyrrhetic Acid and its Consequence on Buspirone Pharmacokinetics in Rats

The aim of this study was to elucidate the inhibition mechanism of 18β-glycyrrhetic acid (GLY) on cytochrome P450 (CYP) activity and in vivo pharmacokinetic consequences of single GLY dose in rats. An in vitro CYP inhibition study in rat liver microsomes (RLM) was conducted using probe substrates for CYPs. Then, an in vivo pharmacokinetics of intravenous and oral buspirone (BUS), a probe substrate for CYP3A, was studied with the concurrent administration of oral GLY in rats. In the in vitro CYP inhibition study, CYP3A was involved in the metabolism of GLY. Moreover, GLY inhibited CYP3A activity with an IC50 of 20.1 ± 10.7 μM via a mixed inhibition mechanism. In the in vivo rat pharmacokinetic study, single oral GLY dose enhanced the area under plasma concentration-time curve (AUC) of intravenous and oral BUS, but the extent of increase in AUC was only minimal (1.12-1.45 fold). These results indicate that GLY can inhibit the in vitro CYP3A-mediated drug metabolism in RLM via a mixed inhibition mechanism. However, the impact of single oral GLY dose on the pharmacokinetics of BUS in rats was limited, showing that GLY could function as merely a weak inhibitor for CYP3A-mediated drug metabolism in vivo. Copyright © 2015 John Wiley & Sons, Ltd.

Inhibitory effect of polysaccharide peptide (PSP) against Tobacco mosaic virus (TMV)

Polysaccharides are essential macromolecules present in all living organisms, and have many kinds of biological activities, such as anti-oxidation, hypoglycemic, enhancing immunity, anti-aging, anti-rheumatism, anti-cancer and so on. In this study, the antiviral activity of polysaccharide peptide (PSP) was tested, compared with Ningnanmycin, and firstly found it has a stronger antiviral activity by using half-leaf method and leaf disk method. Subsequently, the mechanism of antiviral activity of PSP was preliminarily studied. As a result, its antiviral effect was better than the commercial agent Ningnanmycin, despite of protective effect, curative effect and inactivation effect. On the other hand, PSP as a commercial anti-cancer drug could easily and rapidly get in large quantities by liquid fermentation, which makes the industrialized production feasible. Also PSP is less toxic, easily biodegradable and ecofriendly. All the results are suggesting that PSP has potential as a pesticide to be used for the control of plant virus in the future.

The co-use of conventional drugs and herbs among patients in Norwegian general practice: a cross-sectional study

BACKGROUND

Different patient groups are known to use herbal remedies and conventional drugs concomitantly (co-use). This poses a potential risk of herb-drug interaction through altering the drug's pharmacokinetics or pharmacodynamics. Little is known about co-use among patients in general practice. The primary aim of this study was to compare patients in general practice that co-use herbal remedies and conventional drugs with those who do not. The secondary aim was to register the herb-drug combinations with potential clinical relevant interactions among the co-users.

METHOD

A questionnaire based cross-sectional study conducted in the autumn 2011 in a general practice office with four general practitioners (GPs) and one intern in Western Norway. Adults >18 years who came for an office visit were invited. The questionnaire asked about demographics, herbal use, conventional drug use and communication about herbal use. Multivariable logistic regression was used to compare co-users to the other patients.

RESULTS

Of the 381 patients who completed the questionnaire, the prevalence of herbal use was 44%, with bilberry (41%), green tea (31%), garlic (27%), Aloe vera (26%) and echinacea (18%) as the most frequently used. Among those using conventional drugs regularly, 108 (45%) co-used herbs. Close to 40% of patients on anticoagulants co-used herbs, with garlic and bilberry as the most frequent herbs. Compared to all other patients, co-users had significantly (p < 0.05) increased odds to be female (adjOR 2.0), age above 70 years (adjOR 3.3), use herbs to treat an illness (adjOR 4.2), use two or more herbs (polyherbacy, adjOR 12.1) and having experienced adverse effects of herbal use (adjOR 37.5). Co-use was also associated with use of analgesics or dermatological drugs (adjOR 5.1 and 7.9 respectively). Three out of four patients did not discuss herbal use with any health care professional.

CONCLUSION

A sizable proportion of the GP patients co-used herbs with conventional drugs, also combinations with reported interaction potential or additive effects like anticoagulants and garlic. The low disclosure of herbal use to their GP, polyherbacy and the risk of interactions in vulnerable groups like elderly and chronically ill patients, warrant increased awareness among GPs.