[Biotransformation of psoralenoside and isopsoralenoside in Psoraleae Fructus incubated with human intestinal bacteria flora in vitro]

Absorption is crucial to the resultant efficacy of oral drugs where the intestinal bacteria flora functions as one of the first-pass effects.The present study investigated the biotransformation of psoralenoside and isopsoralenoside in Chinese medicine Psoraleae Fructus(the dried fruit of Psoralea corylifolia) with the internationally recognized human intestinal bacteria flora model in vitro.Pso-ralenoside and isopsoralenoside were anaerobically incubated with human intestinal bacteria flora at 37 ℃, respectively, and biotransformation products were analyzed and identified using high-performance liquid chromatography-tandem mass spectrometry(HPLC-MS) and comparison with reference standards.The main biotransformation products of psoralenoside were psoralen and a small amount of 6,7-furano-hydrocoumaric acid, and the main biotransformation products of isopsoralenoside were isopsoralen and a small amount of 5,6-furano-hydrocoumaric acid.

Protective effect of isopsoralen on UVB-induced injury in HaCaT cells via the ER and p38MAPK signaling pathways

This study investigated the protective effect of isopsoralen on UVB-induced damage in HaCaT cells and its molecular mechanism. The cytotoxicity of isopsoralen and its effects on the viability of HaCaT cells were examined using the MTT assay. The effects of UVB irradiation and isopsoralen on the intracellular glutathione (GSH-PX), superoxide dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS) content were examined using commercially available assay kits. Further, the effects of UVB irradiation and isopsoralen on the levels of the inflammatory cytokines TNF-α, IL-6, and IL-1α were examined using enzyme-linked immunosorbent assay. Finally, we examined the effect of adding the estrogen receptor (ER) antagonist ICI182780,780 and the p38MAPK antagonist SB203580 on the changes in inflammatory cytokines induced by isopsoralen treatment and UVB irradiation. Isopsoralen pretreatment markedly inhibited UVB-induced reduction in the viability and proliferation of HaCaT cells. Isopsoralen also reduced UVB-induced increase in the expression of the inflammatory cytokines and the level of free radicals (ROS and MDA), and reversed the UVB-induced suppression of antioxidant activity. Additionally, inhibition of ER and p38MAPK via the addition of their respective antagonists reversed the observed anti-inflammatory effects of Isopsoralen. Isopsoralen can efficiently provide protection against UVB-induced damage in HaCaT cells brought about via oxidation and inflammatory reactions, and the underlying mechanisms involve the ER and p38MAPK pathways. Therefore, Isopsoralen could be used in therapeutic solutions for UVB-induced skin conditions. PRACTICAL APPLICATIONS: Isopsoralen shows antioxidant and anti-inflammatory effects. As natural, healthy, and effective additives, isopsoralen has been widely used in cosmetics and botanical medicine products. The results of this study reveal the molecular mechanisms underlying isopsoralen effects, showing that isopsoralen reverses the effects of UVB irradiation regulating ER and p38MAPK signaling pathways. Consequently, isopsoralen regulates the expression of ER and p38MAPK signaling pathways, thereby reducing the activation of antioxidant and anti-inflammatory activity. These findings suggest that isopsoralen can be used as the base ingredient for antiphotoaging cosmetics and botanical medicine products. This study provides both theoretical and experimental background for isopsoralen deep processing and utilization.

Enhancement of autophagy flux by isopsoralen ameliorates interleukin-1β-stimulated apoptosis in rat chondrocytes

Chondrocyte apoptosis contributes to the pathogenesis of cartilage degeneration in osteoarthritis (OA). We found that isopsoralen pretreatment significantly reversed the increase in DNA fragmentation and apoptosis rate, and significantly decreased the caspase-3 activity and PARP cleavage in IL-1β-treated chondrocytes. Isopsoralen pretreatment markedly inhibited disruption of matrix proteins. Moreover, the expressions of LC3-II and LAMP-1 were markedly increased but the expression of p62/SQSTM1 was remarkably decreased by isopsoralen pretreatment. Importantly, the protective effects of isopsoralen against IL-1β were blocked by pretreatment with autophagy inhibitor 3-MA and bafilomycin A1. These results suggest that isopsoralen ameliorates chondrocyte apoptosis by promoting autophagy flux.[Formula: see text].

Transformation of Psoralen and Isopsoralen by Human Intestinal Microbial In Vitro, and the Biological Activities of Its Metabolites

Psoralen (P) and isopsoralen (IP) are the main active ingredients in the dried fruit of Psoralen corylifolia L. (PC), with a wide range of pharmacology activities. The intestinal bacteria biotransformation plays a central role in the metabolism of the complex ingredients in traditional Chinese medicine (TCM). Our study aimed to investigated the metabolic profile of P and IP in the intestinal condition, co-cultured with human fecal bacteria anaerobically. Four bio-transforming products were obtained, including 6,7-furano-hydrocoumaric acid (P-1) and 6,7-furano-hydro- coumaric acid methyl ester (P-2), which transformed from P, and 5,6-furano-hydrocoumaric acid (IP-1) and 5,6-furano-hydrocoumaric acid methyl ester (IP-2), which were transformed from IP. It is worth mentioning that IP-2 is a new compound that has not been published. Their structures were analyzed based on their spectroscopic data. Moreover, a highly sensitive ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was used to characterize the metabolic pathways of P, IP, and their bio-transforming products in the reaction samples. In addition, the dampening effects against the oxidative stress of P, IP, and their bio-transforming products by human intestinal flora were estimated in vitro via the human colorectal cells (HCT116) and heterogeneous human epithelial colorectal adenocarcinoma cells (Caco-2) cell lines. The results showed that the metabolites have stronger activity than P and IP, which possibly provides a basis for elucidating the treating mechanisms of PC extract against inflammatory bowel disease.

Long-Term Exposure of Psoralen and Isopsoralen Induced Hepatotoxicity and Serum Metabolites Profiles Changes in Female Rats

Pre-clinical safety evaluation of traditional medicines is imperative because of the universality of drug-induced adverse reactions. Psoralen and isopsoralen are the major active molecules and quality-control components of a traditional herbal medicine which is popularly used in Asia, Fructus Psoraleae. The purpose of this study is to assess the long-term effects of psoralen and isopsoralen with low levels on the biochemical parameters and metabolic profiles of rats. Three doses (14, 28, and 56 mg/kg) of psoralen and one dose (28 mg/kg) of isopsoralen were administered to rats over 12 weeks. Blood and selected tissue samples were collected and analyzed for hematology, serum biochemistry, and histopathology. Metabolic changes in serum samples were detected via proton nuclear magnetic resonance (¹H-NMR) spectroscopy. We found that psoralen significantly changed the visceral coefficients, blood biochemical parameters, and histopathology, and isopsoralen extra influenced the hematological index. Moreover, psoralen induced remarkable elevations of forvaline, isoleucine, isobutyrate, alanine, acetone, pyruvate, glutamine, citrate, unsaturated lipids, choline, creatine, phenylalanine, and 4-hydroxybenzoate, and significant reductions of ethanol and dimethyl sulfone. Isopsoralen only induced a few remarkable changes of metabolites. These results suggest that chronic exposure to low-level of psoralen causes a disturbance in alanine metabolism, glutamate metabolism, urea cycle, glucose-alanine cycle, ammonia recycling, glycine, and serine metabolism pathways. Psoralen and isopsoralen showed different toxicity characteristics to the rats.

[Psoralen and isopsoralen improve lipid metabolism disorder via inhibition of NF-κB activation in LO2 cells]

The aim of this paper was to investigate the mechanism and effect of psoralen and isopsoralen in the treatment of lipid accumulation in LO2 cells. Human LO2 cells nonalcoholic fatty liver models were established by using palmitic acid( PA). Then psoralen and isopsoralen were administered for intervention. Intracellular triglyceride( TG) and total cholesterol( TC) content,the cell supernatant alanine aminotransferase( ALT) and aspartate aminotransferase( AST) levels were determined by enzyme method. Cell supernatant proinflammatory cytokines( IL-6,TNF-α) and chemokines( IL-8,MCP-1) were determined by ELISA method. Western blot method was conducted to detect the protein expression of intracellular nuclear factor( NF-κB) p65 phosphorylation( p-p65),nonphosphorylated protein( p65),and transforming factor TGF-β1. Result showed that as compared with the model group,intracellular TG and TC levels,the cell supernatant ALT and AST levels,proinflammatory cytokines and chemokines were decreased( P < 0. 01,P <0. 05); the p-p65/p65 ratio and TGF-β1 protein expression were also significantly decreased( P< 0. 01,P< 0. 05) in psoralen intervention group. As compared with the model cells,intracellular TG content had no significant changes,but all the other indexes were reduced( P<0. 01,P<0. 05) in the cells of isopsoralen intervention group. Psoralen exhibited better effect than isopsoralen( P< 0. 01,P<0. 05). It is concluded that psoralen could improve the adipogenesis of LO2 cells induced by PA; both psoralen and isopsoralen are effective in ameliorating LO2 cells injury induced by PA,reducing inflammation via inhibiting the activation of NF-κB and down-regulating the expression of TGF-β1.

The mechanism of Psoralen and Isopsoralen hepatotoxicity as revealed by hepatic gene expression profiling in SD rats

BACKGROUND

The main bioactive components of Fructus psoraleae, such as psoralen and isopsoralen, are known to be hepatotoxic. However, its underlying mechanism is to be elucidated.

METHODS

To address this, SD rats were randomly divided into control group, 60 mg/kg psoralen group and 60 mg/kg isopsoralen group. Blood was collected to detect serum biochemical indices. RNA was extracted from liver samples, and then, cDNA gene expression profiles were analysed.

RESULTS

Psoralen administration significantly up-regulated serum AST (aspartate aminotransferase) while addition of isopsoralen increased serum ALT (alanine aminotransferase), AST, TBA (total bile acid) and TG (total triglyceride) levels. A total of 172 differentially expressed genes (DEGs) were acquired between psoralen group and control group while 884 DEGs were screened between isopsoralen group and control group. Chemical Carcinogenesis and Metabolism of Xenobiotics by Cytochrome P450 were the two most significantly enriched pathways as revealed by DEGs. Liver was the most impacted organ, and endoplasmic reticulum was the most impacted organelle in subcellular level. Finally, some kinds of cancers and cytochrome p450 oxidoreductase deficiency were predicted. Taken together, psoralen and isopsoralen might cause hepatotoxicity mainly through cytochrome P450 metabolism of xenobiotics. Furthermore, Cyp1a1, Cyp1a2, Gstm1 and Akr7a3 worked as key genes in hepatotoxicity. Moreover, endoplasmic reticulum was the main target subcellular structure in hepatotoxicity induced by psoralen and isopsoralen.

[Analysis of standard decoction of salt-processed Psoraleae Fructus]

The traditional Chinese medicine standard decoction is prepared on the basis of the theory of traditional Chinese medicine and clinical application. With reference to the modern extraction method,the single decoction of traditional Chinese medicine is prepared by the standardized process,and the establishment of its quality standards is conducive to standardizing clinical medication. This research is to set an evaluation standard for the quality of salt-processed Psoraleae Fructus standard decoction. Twelve batches of salt-processed Psoraleae Fructus standard decoctions were prepared. The contents of psoralen and isopsoralen were determined,the transfer and extract rates were calculated,and the pH value was measured; HPLC fingerprint method was established for analysis. The results of the 12 batches of samples revealed that the transfer rates of psoralen and isopsoralen were 17. 10%-26. 40%,14. 70%-22. 70%,respectively; the extract rate was between 14. 7%-27. 0%,and the pH value was between 5. 4-6. 9. Moreover,7 common chromatographic peaks were determined based on fingerprint by using similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine( 2012 A).The similarities of the 12 batches of samples were analyzed and compared,and the results showed that the similarities were all higher than0. 9. In this study,the preparation method for salt-processed Psoraleae Fructus decoction was standard,with high similarities in fingerprint. This study build a convenient and reliable method of comprehensive quality evaluation,with a high precision,stability and repeatability,which can provide a reference for the quality control of salt-processed Psoraleae Fructus dispensing granules.

Isopsoralen ameliorates H2O2-induced damage in osteoblasts via activating the Wnt/β-catenin pathway

Osteoporosis is a disease with a worldwide prevalence that involves a severe loss of bone mineral density and decreased microarchitecture, which increases the risk of bone fracture. The present study evaluated the effects of isopsoralen on osteoblastic OB-6 cells following hydrogen peroxide (H₂O₂)-induced damage and investigated the molecular mechanisms involved in this process. For in vitro experiments, OB-6 osteoblasts were treated with H₂O₂ or H₂O₂ + isopsoralen then the cell viability, apoptosis, reactive oxygen species (ROS) production and calcium accumulation were determined. Results demonstrated that treatment with H₂O₂ reduced cell viability, runt-related transcription factor 2 (RUNX2) and osteocalcin (OCN) expression levels, and calcium deposition, whilst markedly increasing cell apoptosis and ROS production. However, isopsoralen (1 µM) provided significant protection against H₂O₂-induced alterations in osteoblasts. In addition, isopsoralen effectively upregulated protein expression of tankyrase and β-catenin which are the main transductors of the Wnt/β-catenin pathway. Of note, the protective effects of isopsoralen against H₂O₂-induced damage were attenuated in OB-6 cells treated with tankyrase inhibitor XAV-939. In conclusion, the present findings provided evidence that isopsoralen attenuated oxidative stress-induced injury in osteoblasts via the Wnt/β-catenin signaling pathway.

Isopsoralen Enhanced Osteogenesis by Targeting AhR/ERα

Isopsoralen (IPRN), one of the main effective ingredients in Psoralea corylifolia Linn, has a variety of biological effects, including antiosteoporotic effects. In vivo studies show that IPRN can increase bone strength and trabecular bone microstructure in a sex hormone deficiency-induced osteoporosis model. However, the mechanism underlying this osteogenic potential has not been investigated in detail. In the present study, we investigated the molecular mechanism of IPRN-induced osteogenesis in MC3T3-E1 cells. Isopsoralen promoted osteoblast differentiation and mineralization, increased calcium nodule levels and alkaline phosphatase (ALP) activity and upregulated osteoblast markers, including ALP, runt-related transcription factor 2 (RUNX2), and collagen type I alpha 1 chain (COL1A1). Furthermore, IPRN limited the nucleocytoplasmic shuttling of aryl hydrocarbon receptor (AhR) by directly binding to AhR. The AhR target gene cytochrome P450 family 1 subfamily A member 1 (CYP1A1) was also inhibited in vitro and in vivo. This effect was inhibited by the AhR agonists indole-3-carbinol (I3C) and 3-methylcholanthrene (3MC). Moreover, IPRN also increased estrogen receptor alpha (ERα) expression in an AhR-dependent manner. Taken together, these results suggest that IPRN acts as an AhR antagonist and promotes osteoblast differentiation via the AhR/ERα axis.

[Analysis on pharmacokinetics-pharmacodynamics correlation of effective ingredients of Qing'e wan]

To study the pharmacokinetics of three active ingredients in Qing'e wan, namely geniposidic acid, psoralen and isopsoralen, in rats, in order to investigate their correlation in the anti-osteoporotic effect. The rats were taken blood from their eye sockets at different time points after being orally administered with raw and salt-processed Qing'e wan. Geniposidic acid, psoralen and isopsoralen in rats plasma were determined by means of UHPLC-MS/MS to draw the concentration-time curve. The proliferation rate of osteoblasts was taken as the pharmacodynamic index, and determined by MTT method to draw effect-time curve. In comparison between the effect-time curve and the concentration-time curve, the blood concentrations of geniposidic acid and psoralen were close to the peak when the cell proliferation rate reached its peak, indicating a good correlation between them. The peak blood concentration of isopsoralen was slightly lagging behind the peak of efficacy. According to the correlation analysis after fitting the effect-time curve and the concentration-time curve, salt-processed Qing'e wan had a better correlation than the raw one. The above experimental results showed that the effect-time curve and the concentration-time curve of geniposidic acid and psoralen had a good correlation, and the correlation of salt-processed Qing'e wan was better than the raw one.

[Preparation of isopsoralen loaded nanostructured carrier and its in vitro transdermal permeation characteristics]

To increase the permeation and retention of isopsoralen in skin, and improve its bioavailability.Isopsoralen loaded nanostructure liquid carrier (IPRN-NLC) was prepared by high pressure homogenization andoptimized by orthogonal experiment with the encapsulation efficiency, drug loading and average particle size as the evaluation indexes. The in vitro transdermal permeation of IPRN-NLC was evaluated by Franze diffusion cells.The results showed that solid-liquid lipid ratio of optimum IPRN-NLC formulation was 7∶3,drug-lipid ratio of 1∶30, 1% surfactant. Under these conditions, IPRN-NLC had an average encapsulation of （90.25±0.73）%,drug loading of （1.56±0.27）% and an average particle size of (305±1.57) nm.The in vitro transdermal permeation results showed that IPRN-NLC could increase the amount of IPRN permeated though skin, with 3 times of the epidermal retention as compared with IPRN solution. From the results we can know that the IPRN-NLC prepared by high pressure homogenization can improve the permeation andaccumulation of IPRN in the skin, with wide application prospects in the field of transdermal administration.

Effect of isopsoralen on Smad7 in osteoblastic MC3T3-E1 cells

The primary pathological change in postmenopausal osteoporosis (PM-OP) is bone collagen loss caused by estrogen depletion. Osteoblasts synthesize type I collagen, which composes the organic matrix of bone. Although isopsoralen stimulates osteoblastic cell proliferation and differentiation, transforming growth factor (TGF)-β1 is an important cell signaling factor for stimulating collagen synthesis. To explore the association between isopsoralen and the synthesis of collagen in vitro, the molecular and biological association between isopsoralen and TGF-β signaling was examined. (CAGA) 12-luciferase-reporter gene was used to measure TGF-β1 signaling activity. Type I collagen was detected by semiquantitative reverse transcription polymerase chain reaction, and mothers against decapentaplegic homolog 7 (Smad7) protein expression levels were analyzed by western blotting. The expression of collagen in MC3T3-E1 cells stimulated with isopsoralen was significantly upregulated compared with the control groups (P<0.05). Conversely, isopsoralen significantly decreased Smad7 protein expression compared with the control groups (P<0.05). Moreover, it was observed that isopsoralen activates the TGF-β1 signaling pathway and ultimately promotes collagen synthesis through inhibition of Smad7 protein expression. Therefore, isopsoralen is a potential target for the treatment of PM-OP.

Isolation and purification of psoralen and isopsoralen and their efficacy and safety in the treatment of osteosarcoma in nude rats

BACKGROUND

Modern studies have shown that psoralen has a significant inhibitory effect on tumor growth in a variety of animals and humans.

OBJECTIVE

To obtain coumarin compounds - psoralen and isopsoralen - from traditional Chinese medicine Psoralea corylifolia L. using chromatographic techniques and isolation and purification methods, and to observe the transplanted tumor growth inhibitory effects and adverse reactions of psoralen and isopsoralen in nude rats with osteosarcoma.

METHODS

Dried ripe fruits of Psoralea corylifolia L. were taken as the raw material to prepare crude extract of Psoralea corylifolia L. by ethanol reflux method. Column chromatography was used to isolate the crude extract; compounds were structurally identified based on (1)H-NMR, (13)C-NMR spectra, the two compounds were identified as psoralen andisopsoralen, and their contents were 99.7% and 99.6, respectively. Nude rat model of osteosarcoma was established; the rats were randomized into: normal saline group, psoralen low- and high-dose groups, isopsoralen low- and high-dose groups, and cisplatin group. Osteosarcoma volume and weight inhibition rates in nude rats in each group were observed; radioimmunoassay was used to determine the serum alkaline phosphatase activity; peripheral blood cell and bone marrow nucleated cell counts were determined; light microscopy was used to observe heart, liver, spleen, lung, kidney, and tumor histopathology; and electron microscopy was used to observe the fine structure of tumor cells.

RESULTS

Tumor volume inhibition rates were 43.75% and 40.18%, respectively, in the psoralen and isopsoralen low-dose groups, and tumor weight inhibition rates were 38.83% and 37.77%. Tumor volume inhibition rates were 67.86% and 66.96%, respectively, in the psoralen and isopsoralen high-dose groups, and tumor weight inhibition rates were 49.47% and 47.87%. Psoralen and ispsoralen markedly lowered serum AKP level. Psoralen and isopsoralen induced apoptosis or necrosis of osteosarcoma. After administration of high doses of psoralen and isopsoralen, toxic reactions such as writhing, lassitude, and hypoactivity were seen. Kidney histopathology showed tubulointerstitial dilatation and congestion, and inflammatory cell aggregation in the renal intercellular space. Psoralen and isopsoralen did not cause any significant toxic side effects to the bone marrow, or other organs such as heart, lung, liver, and spleen.

CONCLUSION

Psoralen and isopsoralen have growth inhibitory effects on transplanted tumor in nude rats with osteosarcoma, and can induce tumor cell apoptosis or necrosis, without significant toxic effects.

A UPLC-MS/MS method for in vivo and in vitro pharmacokinetic studies of psoralenoside, isopsoralenoside, psoralen and isopsoralen from Psoralea corylifolia extract

ETHNOPHARMACOLOGICAL RELEVANCE

The dried fruit of Psoralea corylifolia L. has been used to prevent and treat vitiligo, osteoporosis, arthralgia and asthma in Traditional Chinese Medicine for some 1600 years. Psoralen (P), isopsoralen (IP), psoralenoside (PO) and isopsoralenoside (IPO) are the major coumarins and coumarin-related benzofuran glycosides in Psoraleae Fructus, which have been reported to show estrogen-like activity, osteoblastic proliferation accelerating activity, antitumor effects and antibacterial activity. The first aim of this study is to develop a rapid, sensitive and selective ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) approach for simultaneous determination of PO, IPO, P and IP in rat plasma and samples collected from in vitro incubation experiments. The second aim is to investigate the pharmacokinetic properties of PO, IPO, P and IP after oral administration of Psoralea corylifolia extract (PCE) to rats. The third aim is to confirm the biotransformation of PO to P or IPO to IP under gastrointestinal conditions.

MATERIALS AND METHODS

A UPLC-MS/MS method with a C18 column and a mobile phase of methanol-0.1% aqueous formic acid was validated according to the criteria in FDA guidelines about bioanalytical method, which was developed to investigate the pharmacokinetic behavior of PO, IPO, P and IP from PCE and the metabolic pathways of PO to P or IPO to IP.

RESULTS

The criteria for establishment of a new UPLC-MS/MS method including selectivity, linearity, accuracy, precision, extraction recovery, matrix effect and stability were validated. This method was successfully applied to the quantitative determination of PO, IPO, P and IP in biological samples collected from both in vitro incubations and in vivo rat experiments. After oral administration of PCE to rat, pharmacokinetic parameters of these four compounds indicated that in vivo biotransformation may occur between PO and P or IPO and IP. Purified benzofuran glycosides fraction (PBGF), containing only PO and IPO, was orally administered to rats to further confirm the biotransformation of PO to P or IPO to IP under gastrointestinal conditions. An in vitro incubation study elucidated that PO and IPO were metabolized to P and IP by intestinal microflora through de-glucosylation.

CONCLUSIONS

This paper developed a rapid, sensitive and selective UPLC-MS/MS method for simultaneous determination of PO, IPO, P and IP from PCE in biological samples, and investigated on their comprehensive in vivo and in vitro pharmacokinetic studies. These obtained results showed that the metabolism by intestinal bacteria plays an important role in pharmacological effects of orally administered PCE.

Isobavachalcone and bavachinin from Psoraleae Fructus modulate Aβ42 aggregation process through different mechanisms in vitro

Spontaneous aggregation of Aβ is a key factor in the development of Alzheimer's disease. In searching for Aβ aggregation inhibitors from traditional Chinese herbal medicines, we identified two active compounds from Psoraleae Fructus, namely isobavachalcone and bavachinin. We further demonstrated that the two compounds modulate Aβ42 aggregation process through different mechanisms. Isobavachalcone significantly inhibits both oligomerization and fibrillization of Aβ42, whereas bavachinin inhibits fibrillization and leads to off-pathway aggregation. Both of the compounds attenuated Aβ42-induced toxicity in a SH-SY5Y cell model. These findings may provide valuable information for new drug development and Alzheimer's therapy in the future.