Bakuchiol-induced caspase-3-dependent apoptosis occurs through c-Jun NH2-terminal kinase-mediated mitochondrial translocation of Bax in rat liver myofibroblasts

Bakuchiol, a natural constituent and its pharmacological benefits

Background and aims

Natural compounds extracted from medicinal plants have recently gained attention in therapeutics as they are considered to have lower Toxicity and higher tolerability relative to chemically synthesized compounds. Bakuchiol from Psoralea corylifolia L. is one such compound; it is a type of meroterpene derived from the leaves and seeds of Psoralea corylifolia plants. Natural sources of bakuchiol have been used in traditional Chinese and Indian medicine for centuries due to its preventive benefits against tumors and inflammation. It plays a strong potential role as an antioxidant with impressive abilities to remove Reactive Oxygen Species (ROS). This review has focused on bakuchiol's extraction, therapeutic applications, and pharmacological benefits.

Methods

A search strategy has been followed to retrieve the relevant newly published literature on the pharmacological benefits of bakuchiol. After an extensive study of the retrieved articles and maintaining the inclusion and exclusion criteria, 110 articles were finally selected for this review.

Results

Strong support of primary research on the protective effects via antitumorigenic, anti-inflammatory, antioxidative, antimicrobial, and antiviral activities are delineated.

Conclusions

From ancient to modern life, medicinal plants have always been drawing the attention of human beings to alleviate ailments for a healthy and balanced lifestyle. This review is a comprehensive approach to highlighting bona fide essential pharmacological benefits and mechanisms underlying their therapeutic applications.

Bakuchiol inhibits lung cancer by modulating tumor microenvironment and the expression of PD-L1

Immune checkpoint therapy is an emerging frontier in cancer therapy. With the aim to develop an efficient herb derived compound to facilitate immune checkpoint therapy, here we investigate if a herb-derived compound, Bakuchiol (BAK), can be used to treat lung cancer and elucidate if BAK could serve as a PD-L1 regulator. To this end, a murine lung cancer model was established by subcutaneously inoculating murine Lewis lung carcinoma (LLC) cells. BAK of 5 to 40 mg/kg was used for treatment in vivo for 15 days. On Day 15, the population of CD4+ and CD8+ T cells, Treg cells. BAK could effectively inhibit tumor growth by starting treatment either on Day 0 or 6 after tumor inoculation at doses of 5-40 mg/kg. BAK treatment increased the population of cytotoxic immune cells (i.e., CD8+ T cells, and M1 macrophages), meanwhile decreasing pro-tumor immune cells (i.e., CD3+ T cells, Treg cells, and M2 macrophages). Anti-inflammatory cytokines, including IL1β, IL2, IFNγ, TNF-α, IL4 and IL10 were upregulated by BAK. PD-L1 expression in the tumor was also lowered by BAK. AKT and STAT3 signaling were inhibited by BAK. BAK is an efficient agent in reducing LLC tumor growth. These data support the potential of BAK as a new drug for treating lung cancer by serving as a PD-L1 inhibitor that suppresses the activation of AKT and STAT3.

Bakuchiol from Psoralea corylifolia L. Ameliorates acute kidney injury and improves survival in experimental polymicrobial sepsis

Bakuchiol (BAK) is a prenylated phenolic mono-terpene extracted from the fruit of Psoralea corylifolia L., which exerts a protective effect on organs. However, whether BAK has a protective effect on sepsis-induced acute kidney injury (S-AKI) is not clear. In our study we have demonstrated for the first time that pretreatment with BAK significantly reduced bacterial load, inflammation and renal oxidative stress in caecal ligation and puncture (CLP)-induced sepsis. Moreover, CLP-induced renal histological damage, mortality and clinical signs were markedly attenuated by BAK. Additionally, BAK inhibited sepsis-induced activation of NF-κB and p38 MAPK signaling in the kidneys. The evidence presented here has confirmed that BAK exerts multifunctional activity in protection against S-AKI. This action of BAK is probably due to the blockade of the NF-κB and p38 MAPK signaling pathways. Our findings offer a novel potential for BAK in protection against sepsis and S-AKI.

Activation of Caspase-3 by Terpenoids and Flavonoids in Different Types of Cancer Cells

BACKGROUND

Caspase-3 is accountable for the execution of apoptosis. Recently, it has gained attention as a promising target for the discovery of natural products as anticancer agents.

METHODS

We examined the efficacy of two different sets of natural products (terpenoids and flavonoids) towards caspase-3 activity adopting in silico, cell-free and cell-based activity and real-time gene expression analysis.

RESULTS

It was observed that terpenes activate caspase-3 activity in both the cell-free and cell-based systems, which was supported by the gene expression analysis, binding energy and activation constant. Flavonoids' action, however, was limited to the cell-based system and transcriptional regulation suggesting their indirect association, which enhanced the enzyme activity and up-regulated the expression of mRNA levels in the cells. Among the tested natural products, (+) carvone was observed to be the best activator of caspase-3 in K562 (34.4 μM), WRL-68 (22.3 μM), HeLa (18.7 μM), MCF-7 (39.4 μM) and MDA-MB-231 cell lines (45.1 μM).

CONCLUSION

Overall, terpenoids have a persistent activation of caspase-3 in all the investigated systems, while flavonoids circuitously affect the enzyme activity.

Bakuchiol suppresses oestrogen/testosterone-induced Benign Prostatic Hyperplasia development through up-regulation of epithelial estrogen receptor β and down-regulation of stromal aromatase

Estrogens and androgens play critical roles during benign prostatic hyperplasia (BPH) development. Estrogen receptors (ERs), androgen receptor (AR) and aromatase, the key conversion enzyme of androgen to estrogen, are thought to be the effective targets for BPH treatment. Bakuchiol (Ba)-containing herb Psoralea corylifolia has been long-termed used for BPH patients in traditional Chinese medicine while the role and regulatory mechanism of Ba involved remain unclear. Human prostatic cell lines WPMY-1 and BPH-1 and oestrodial/testosterone-induced BPH rats were used as the in vitro and in vivo models. Ba significantly inhibited the proliferation of WPMY-1 and BPH-1 cells. In E2/T-induced BPH model, Ba treatment also significantly inhibited the enlargement of prostate, decreased PI values, reduced the thickness of periglanular smooth muscle layer, and down-regulated the expressions of PCNA and smooth muscle cell marker α-SMA, all of which were highly induced in BPH rats. Moreover, the basal and PGE2-induced expressions of aromatase were reduced in Ba-stimulated WPMY-1 cells, while the expression of ERβ was highly increased in Ba-stimulated BPH-1 cells, both of which are consistent with the findings in Ba group in vivo. Ba induced ERE activity in BPH-1 cells as E2 did; however, silence of ERβ not ERα, blocked Ba-induced ERE activity while E2 still exhibited the significant ERE activity, indicating the regulation of estrogen signaling by Ba is particularly via ERβ. In conclusion, by down-regulation of stromal aromatase and up-regulation of epithelial ERβ, Ba contributes to the balance of estrogen and androgen signaling and further inhibits BPH development.

DBA-induced caspase-3-dependent apoptosis occurs through mitochondrial translocation of cyt-c in the rat hippocampus

Dibromoacetic acid (DBA), a by-product of disinfection, develops in drinking water during chlorination or ozonation processes. Water intake is the main source of DBA exposure in humans, which is potentially neurotoxic. The present study investigated the neurotoxic effects of DBA by assessing the behavioral and biochemical characteristics of Sprague Dawley rats intragastrically treated with DBA at concentrations of 20, 50 and 125 mg kg^-1 body weight for 28 consecutive days. The results indicated that animal weight gain and food consumption were not significantly affected by DBA. However, shuttle box tests showed increases in mistake frequency and reaction latency between the control and high-dose group. We found significant changes in hippocampal neurons by histomorphological observation. Additionally, biochemical analysis indicated enhanced production of reactive oxygen species (ROS) resulting in disruption of cellular antioxidant defense systems including decreased mitochondrial superoxide dismutase (SOD) activity and release of cytochrome c (cyt-c) from mitochondria into the cytosol, which can induce neuronal apoptosis. Furthermore, the increase of cyt-c in the cytosol enhanced caspase-3 and caspase-9 activity, which was confirmed by poly ADP-ribose polymerase-1 (PARP-1) cleavage to its signature fragment of 85 kDa and decreased levels of protein kinase C-δ (PKC-δ) in the hippocampus. Meanwhile, DBA treatment caused differential modulation of apoptosis-associated proteins and mRNAs for phosphorylated apoptosis signal regulating kinase 1 (p-ASK-1), phosphorylated c-jun N-terminal kinase (p-JNK), cyt-c, Bax, Bcl-2, caspase-9 and cleaved caspase-3 accompanied by DNA damage. Taken together, these data indicate that DBA may induce neurotoxicity via caspase-3-dependent apoptosis involving mitochondrial translocation of cyt-c in the rat hippocampus.

Bakuchiol attenuates myocardial ischemia reperfusion injury by maintaining mitochondrial function: the role of silent information regulator 1

Ischemia reperfusion (IR) injury (IRI) is associated with poor prognoses in the settings of both cardiac surgery and ischemic heart disease and causes mitochondrial oxidative stress and cell death. Silent information regulator 1 (SIRT1), a member of the histone deacetylase family, exerts anti-IRI effects. Bakuchiol (BAK), an analog of resveratrol and a monoterpene phenol isolated from the seeds of Psoralea corylifolia (Leguminosae), protects tissues from injury. This study was designed to investigate the protective effects of BAK treatment in the setting of myocardial IRI and to elucidate the potential mechanism of those effects. Prior to induction of IR, isolated rat hearts or cardiomyocytes were exposed to BAK in either the absence or presence of the SIRT1 inhibitors Sirtinol and SIRT1 siRNA. BAK exerted cardioprotective effects, as evidenced by the improvements noted in cardiac function following ischemia, attenuated myocardial apoptosis, and changes in several biochemical parameters (including increases in the level of the anti-apoptotic protein Bcl2, decreases in the level of the pro-apoptotic protein Bax, and decreases in the cleaved Caspase 3 level). However, Sirtinol and SIRT1 siRNA each blocked BAK-induced cardioprotection by inhibiting SIRT1 signaling. Additionally, BAK significantly increased the activities of mitochondrial succinate dehydrogenase, cytochrome c oxidase, and mitochondrial superoxide dismutase and decreased the production of malondialdehyde. These findings suggested that BAK significantly attenuated IR-induced mitochondrial oxidative damage. However, Sirtinol and SIRT1 siRNA abolished BAK-dependent mitochondrial function. In summary, our results demonstrate that BAK treatment attenuates IRI by attenuating IR-induced mitochondrial oxidative damage via the activation of SIRT1/PGC-1α signaling.

The Chemical Constituents and Bioactivities of Psoralea corylifolia Linn.: A Review

Psoralea corylifolia Linn. (P. corylifolia) is an important medicinal plant with thousands of years of clinical application. It has been widely used in many traditional Chinese medicine formulas for the treatment of various diseases such as leucoderma and other skin diseases, cardiovascular diseases, nephritis, osteoporosis, and cancer. Phytochemical studies indicated that coumarins, flavonoids, and meroterpenes are the main components of P. corylifolia, and most of these components are present in the seeds or fruits. The extracts and active components of P. corylifolia demonstrated multiple biological activities, including estrogenic, antitumor, anti-oxidant, antimicrobial, antidepressant, anti-inflammatory, osteoblastic, and hepatoprotective activities. This paper systematically summarized literatures on the chemical constituents and biological activities of P. corylifolia, which provided useful information for the further research and development toward this potent medicinal plant.

Synthesis and anti-proliferative evaluation of novel 3,4-dihydro-2H-1,3-oxazine derivatives of bakuchiol

Anti-proliferation study of new bakuchiol analogs revealed the anti-pancreatic potential of aliphatic oxazine derivatives of bakuchiol that activate caspase-9 and -3 and cleave PARP-1.

Psoralea glandulosa as a potential source of anticancer agents for melanoma treatment

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on melanoma cancer, the present study was undertaken to investigate the biological activity of the resinous exudate of aerial parts from Psoralea glandulosa, and its active components (bakuchiol (1), 3-hydroxy-bakuchiol (2) and 12-hydroxy-iso-bakuchiol (3)) against melanoma cells (A2058). In addition, the effect in cancer cells of bakuchiol acetate (4), a semi-synthetic derivative of bakuchiol, was examined. The results obtained show that the resinous exudate inhibited the growth of cancer cells with IC₅₀ value of 10.5 μg/mL after 48 h of treatment, while, for pure compounds, the most active was the semi-synthetic compound 4. Our data also demonstrate that resin is able to induce apoptotic cell death, which could be related to an overall action of the meroterpenes present. In addition, our data seem to indicate that the apoptosis correlated to the tested products appears, at least in part, to be associated with an increase of reactive oxygen species (ROS) production. In summary, our study provides the first evidence that P. glandulosa may be considered a source of useful molecules in the development of analogues with more potent efficacy against melanoma cells.

Synthesis of ∆3-2-hydroxybakuchiol analogues and their growth inhibitory activity against rat UMR106 cells

A series of ∆³-2-hydroxybakuchiol analogues have been synthesized and tested for their growth inhibitory activity against rat UMR106 cells by using the MTT method. Some of them exhibit enhanced activities compared with the natural product, and the preliminary SAR profile shows that the chain tail on the natural product could be subtly modified to enhance the activity and the aromatic moiety or the terminal olefin on the main chain can also be modified without any evident loss of activity. The stereo-configuration of the quaternary chiral center has an important influence on the activity.

Progress on understanding the anticancer mechanisms of medicinal mushroom: inonotus obliquus

Cancer is a leading cause of death worldwide. Recently, the demand for more effective and safer therapeutic agents for the chemoprevention of human cancer has increased. As a white rot fungus, Inonotus obliquus is valued as an edible and medicinal resource. Chemical investigations have shown that I. obliquus produces a diverse range of secondary metabolites, including phenolic compounds, melanins, and lanostane-type triterpenoids. Among these are active components for antioxidant, antitumoral, and antiviral activities and for improving human immunity against infection of pathogenic microbes. Importantly, their anticancer activities have become a hot recently, but with relatively little knowledge of their modes of action. Some compounds extracted from I. obliquus arrest cancer cells in the G0/G1 phase and then induce cell apoptosis or differentiation, whereas some examples directly participate in the cell apoptosis pathway. In other cases, polysaccharides from I. obliquus can indirectly be involved in anticancer processes mainly via stimulating the immune system. Furthermore, the antioxidative ability of I. obliquus extracts can prevent generation of cancer cells. In this review, we highlight recent findings regarding mechanisms underlying the anticancer influence of I. obliquus, to provide a comprehensive landscape view of the actions of this mushroom in preventing cancer.

Protective Role of Psoralea corylifolia L. Seed Extract against Hepatic Mitochondrial Dysfunction Induced by Oxidative Stress or Aging

The accumulation of oxidative damage and mitochondrial dysfunction is an important factor that contributes to aging. The Psoralea corylifolia seeds (PCS), commonly known as “Boh-Gol-Zhee” in Korea, have been used traditionally as a medicinal remedy. We investigated whether an extract of PCS has protective effects on oxidative stress and mitochondrial function in hepatocytes. The PCS extract showed an antisenescence effect on human diploid fibroblasts as evidenced by a decreased expression of p16^INK4a mRNA and senescence-associated β-galactosidase staining. PCS extract treatment reduced H₂O₂-induced reactive oxygen species (ROS) production in HepG2 cells, inhibited ROS production in hepatocytes of aged mice, and increased superoxide dismutase activity. In H₂O₂-treated HepG2 cells, PCS extract treatment recovered ATP production. PCS extract treatment recovered the oxygen consumption rate and inhibited reduction of mitochondrial membrane potential induced by oxidative stress, suggesting improvement of mitochondrial function. In addition, PCS extract treatment recovered peroxisome proliferator-activated receptor γ coactivator 1α and carnitine palmitoyltransferase 1 mRNA and protein expression, and inhibited mitochondrial genome damage. Treatment with the major component of PCS extract, bakuchiol, also recovered mitochondrial dysfunction. On the basis of these results, we conclude that PCS extract inhibits ROS production and mitochondrial dysfunction induced by oxidative stress in hepatocytes.

Compounds isolated from Psoralea corylifolia seeds inhibit protein kinase activity and induce apoptotic cell death in mammalian cells

Objectives

Psoralea corylifolia is a plant widely used in traditional Chinese medicine, e.g. for its chemopreventive effect. To identify active substances responsible for this effect, we investigated pharmacological effects of 11 compounds isolated from the seeds of this plant (newly described substances: 7, 2′, 4′-trihydroxy-3-arylcoumarin and psoracoumestan).

Methods

The influence of distinct compounds on different signal transduction pathways (cell proliferation, survival, angiogenesis and metastasis) was screened via analysis of the activity of 24 protein kinases, mitogen activated protein kinase phosphorylation via Western blot, cytotoxicity was shown using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and determination of caspase activity. Oxidative stress was detected via 2′,7′-dichlorofluorescein fluorescence.

Key findings

Some compounds showed cytotoxic effects (H4IIE, Hct116, C6 cells) mainly mediated via induction of apoptosis. Distinct compounds caused a strong inhibition of MAPK/ERK kinase (MEK) phosphorylation, weak effects on extracellular-signal regulated kinase (ERK) phosphorylation and no significant effect on p38 and c-Jun amino-terminal kinase. Corylifol C and, to a lesser extent, xanthoangelol are potent protein kinase inhibitors (inhibitory concentration 50% values for epidermal growth factor receptor (EGFR): 1.1 and 4.4 × 10−6 μg/ml, respectively). Because EGFR, MEK and ERK are kinases involved in cellular proliferation, an inhibition of these enzymes may be useful to cause chemopreventive effects.

Conclusions

Distinct compounds isolated from P. corylifolia showed a high potential to influence cellular pathways, e.g. by inhibition of protein kinases that may be interesting for pharmacological purposes.

Apoptotic effect of propyl gallate in activated rat hepatic stellate cells

Hepatic stellate cells (HSCs) play a central role in liver fibrosis. Inhibition of HSC growth and induction of apoptosis have been proposed as therapeutic strategies for the treatment and prevention of liver fibrosis. Propyl gallate (PG) is an antioxidant widely used in processed foods, cosmetics and medicinal preparations. However, the anti-fibrotic effect of PG in liver injury is unclear. In this study, we investigated whether PG could induce apoptosis in activated HSCs. Treatment of activated HSCs with PG inhibited cell viability in a dose- and time-dependent manner. PG induced apoptosis as demonstrated by morphological changes, poly(ADP-ribose) polymerase (PARP) cleavage, caspase-3 cleavage, increased Bad expression, and decreased Bcl-2 protein expression. Through stimulation of the activation of c-Jun NH2-terminal protein kinase (JNK) and p38 mitogen-activated protein kinases (MAPK) by PG treatment, we demonstrated that JNK and p38 MPAK are not involved in PG-induced apoptosis using their specific inhibitors. Taken together, these findings indicate that PG induces apoptosis in activated HSCs. The potential anti-fibrotic effect of PG warrants further evaluation.

Madecassoside, a triterpenoid saponin isolated from Centella asiatica herbs, protects endothelial cells against oxidative stress

This study aimed to investigate the effect of madecassoside against oxidative stress-induced injury of endothelial cells. Hydrogen peroxide (H(2)O(2), 500 µmol/L) was employed as an inducer of oxidative stress in human umbilical vein endothelial cells (HUVECs). Cell apoptosis was detected by Hoechst 33258 staining and flow cytometry. Caspase-3 activity and mitochondria membrane potential were further examined. As a result, madecassoside (10, 30, 100 µmol/L) could reverse morphological changes, elevate cell viability, increase glutathione levels, and decrease lactate dehydrogenase and malondialdehyde levels caused by H(2)O(2) in a concentration-dependent manner. It attenuated apoptosis, preventing the activation of caspase-3 and the loss of mitochondria membrane potential, as well as the phosphorylation of p38 mitogen-activated protein kinase (MAPK) in HUVECs. These data suggested that madecassoside could protect HUVECs from oxidative injury, which was probably achieved by inhibiting cell apoptosis via protection of mitochondria membranes and downregulation of the activation of caspase-3 and p38 MAPK.

Pathways responsible for apoptosis resulting from amadori-induced oxidative and nitrosative stress in human mesothelial cells

BACKGROUND

Apoptosis and inflammatory/oxidative stress have been associated with hyperglycemia in human peritoneal mesothelial cells (HPMCs) and other cell types. We and others have highlighted the role of early products of non-enzymatic protein glycation in inducing proinflammatory conditions and increasing apoptotic rates in HPMCs. Loss of HPMCs seems to be a hallmark of complications associated with peritoneal membrane dysfunction. The aim of this work is to elucidate the mechanisms by which Amadori adducts may act upon HPMC apoptosis.

METHODS

HPMCs isolated from different patients were exposed to different Amadori adducts, i.e. highly glycated hemoglobin (10 nM) and glycated bovine serum albumin (250 μg/ml), to study cell death and several proapoptotic markers by different experimental approaches.

RESULTS

Amadori adducts, but not their respective controls, impaired cell proliferation and cell viability by means of apoptosis in a time-dependent manner. They regulated the intrinsic mitochondrial cell death signaling pathway and modulated activation of caspases, Bax, iNOS, p53, NF-κB, and mitogen-activated protein kinases (p38 and JNK) through different reactive oxygen and nitrosative species.

CONCLUSIONS

Our data strongly support the idea that long-term hyperglycemia could act as an inducer of apoptosis in HPMCs through Amadori adducts, involving different oxidative and nitrosative reactive species.

Bax and calpain mediate excitotoxic oligodendrocyte death induced by activation of both AMPA and kainate receptors

Sustained activation of AMPA and kainate receptors in rat oligodendrocytes induces cytosolic calcium overload, mitochondrial depolarization, and an increase of reactive oxygen species, resulting in cell death. Here, we provide evidence that Bax, a proapoptotic member of the Bcl-2 protein family, is involved in excitotoxic apoptotic death of oligodendrocytes and that calpain mediates Bax activation. Cultured Bax(-/-) oligodendrocytes, obtained from the optic nerve of Bax knock-out mice, were resistant to AMPA and kainate receptor-mediated insults. In turn, both mitochondrial calcium uptake and mitochondrial alterations after excitotoxic insults were diminished in Bax-null oligodendrocytes. Moreover, pretreatment with furosemide, a blocker of Bax translocation to mitochondria, significantly protected rat and mouse oligodendrocytes from AMPA- and kainate-induced damage; in contrast, bongkrekic acid, a blocker of the mitochondrial permeability transition pore, had no effect. Finally, we analyzed the participation of calpain, which cleaves Bax and is activated by AMPA and kainate, in oligodendrocyte death. Pretreatment with 3-(4-iodophenyl)-2-mercapto-(Z)-2-propenoic acid (PD150606), a broad cell-permeable calpain inhibitor, and two additional calpain inhibitors diminished Bax activation, inhibited its translocation to mitochondria, and attenuated all apoptotic events resulting from excitotoxic insults to rat oligodendrocytes. Together, these results indicate that Bax and calpain are essential intermediaries of the mitochondria-dependent death pathway, triggered by AMPA and kainate receptor activation in oligodendrocytes.

Novel bisstyryl derivatives of bakuchiol: targeting oral cavity pathogens

Novel bisstyryl derivatives of bakuchiol using Heck coupling reaction as the key step were synthesized and screened against a panel of six oral cavity pathogens for their antimicrobial activity. Four compounds (9-12) showed two to fourfold and four to eightfold better activity (MIC 0.25-16 microg/ml) than bakuchiol and triclosan respectively. These compounds effectively inhibit the biofilm formation of single and multiple species at 2 - 8 x MICs. 4- and 4'-Hydroxy/methoxy styryl moieties of the bakuchiol derivatives play a pivotal role towards the activity as established in the SAR studies. Mechanism of action studies revealed microbial membrane structure disruption as the probable mode of action of these compounds.

Antitumor activity of water extract of a mushroom, Inonotus obliquus, against HT-29 human colon cancer cells

In the current study, it was demonstrated that the hot water extract of I. obliquus (IOWE) exerts inhibitory activity against the proliferation of human colon cancer cells (HT-29). The inhibitory effect of IOWE on the growth of HT-29 cancer cells was evaluated by treating cells with IOWE at concentrations of 0.25, 0.5 and 1.0 mg/mL for 24 or 48 h. The IOWE inhibited cell growth in a dose-dependent manner, and this inhibition was accompanied by apoptotic cell death. The maximum inhibitory effect (56%) was observed when IOWE was treated at a concentration of 1.0 mg/mL for 48 h. The apoptotic effect of IOWE on HT-29 cells was also confirmed by flow cytometric analysis. In addition, the apoptotic cell percentage was closely associated with down-regulation of Bcl-2 and up-regulation of Bax and caspase-3. The results suggest that IOWE would be useful as an antitumor agent via the induction of apoptosis and inhibition of the growth of cancer cells through up-regulation of the expression of proapoptotic proteins and down-regulation of antiapoptotic proteins.

Bioactive constituents from Chinese natural medicines. XXXIII. Inhibitors from the seeds of Psoralea corylifolia on production of nitric oxide in lipopolysaccharide-activated macrophages

The methanolic extract from the seeds of Psoralea corylifolia was found to inhibit production of nitric oxide (NO) in lipopolysaccharide-activated mouse peritoneal macrophages. Among the isolated compounds, bavachinin (IC(50)=26 microM), isobavachalcone (17 microM), neobavaisoflavone (ca. 29 microM), corylifol A (ca. 21 microM), and psoralidin (ca. 23 microM) significantly inhibited the accumulation of nitrite (NO(2)(-)) as a marker of production of NO. Bakuchiol, which is mainly contained in the extract, also showed weak activity at 10 microM, but cytotoxic effects were observed more than 30 microM.

Fibrosis and cirrhosis reversibility - molecular mechanisms

The concept that liver fibrosis is a dynamic process with potential for regression as well as progression has emerged in parallel with clinical evidence for remodeling of fibrotic extracellular matrix in patients who can be effectively treated for their underlying cause of liver disease. This article reviews recent discoveries relating to the cellular and molecular mechanisms that regulate fibrosis regression, with emphasis on studies that have used experimental in vivo models of liver disease. Apoptosis of hepatic myofibroblasts is discussed. The functions played by transcription factors, receptor-ligand interactions, and cell-matrix interactions as regulators of the lifespan of hepatic myofibroblasts are considered, as are the therapeutic opportunities for modulating these functions. Growth factors, proteolytic enzymes, and their inhibitors are discussed in detail.

Sphingosine 1-phosphate regulates regeneration and fibrosis after liver injury via sphingosine 1-phosphate receptor 2

Sphingosine 1-phosphate (S1P), a bioactive lipid mediator, stimulates proliferation and contractility in hepatic stellate cells, the principal matrix-producing cells in the liver, and inhibits proliferation via S1P receptor 2 (S1P(2)) in hepatocytes in rats in vitro. A potential role of S1P and S1P(2) in liver regeneration and fibrosis was examined in S1P(2)-deficient mice. Nuclear 5-bromo-2'-deoxy-uridine labeling, proliferating cell nuclear antigen (PCNA) staining in hepatocytes, and the ratio of liver weight to body weight were enhanced at 48 h in S1P(2)-deficient mice after a single carbon tetrachloride (CCl(4)) injection. After dimethylnitrosamine (DMN) administration with a lethal dose, PCNA staining in hepatocytes was enhanced at 48 h and survival rate was higher in S1P(2)-deficient mice. Serum aminotransferase level was unaltered in those mice compared with wild-type mice in both CCl(4)- and DMN-induced liver injury, suggesting that S1P(2) inactivation accelerated regeneration not as a response to enhanced liver damage. After chronic CCl(4) administration, fibrosis was less apparent, with reduced expression of smooth-muscle alpha-actin-positive cells in the livers of S1P(2)-deficient mice, suggesting that S1P(2) inactivation ameliorated CCl(4)-induced fibrosis due to the decreased accumulation of hepatic stellate cells. Thus, S1P plays a significant role in regeneration and fibrosis after liver injury via S1P(2).

Adenoviral-mediated up-regulation of Otos, a novel specific cochlear gene, decreases cisplatin-induced apoptosis of cultured spiral ligament fibrocytes via MAPK/mitochondrial pathway

Previous reports have implicated Otos, a novel specific gene expressed by spiral ligament fibrocytes (SLFs) with unclear functions, as a protective gene for cochlea. However, whether Otos gene could protect SLFs against cisplatin (DDP)-induced apoptosis remains largely unknown. In the present study, we utilized Adenoviral-mediated gene transfection to up-regulate Otos expression in cultured SLFs and further assessed the cell viability and apoptosis as well as possible MAPK and mitochondrial pathways. As expected, the data showed that Otos up-regulation significantly decreased apoptosis of SLFs induced by DDP possibly through activation of ERK and partial inhibition of JNK and mitochondrial pathway but not p-38 pathway, suggesting Otos as a potential protective gene for cochlea and raising the possibility of Otos up-regulation as a promising approach to DDP-induced deafness therapy.

Bakuchiol analogs inhibit monoamine transporters and regulate monoaminergic functions

Monoamine transporters play key roles in controlling monoamine levels and modulating monoamine reuptake. The objective of the present study was to identify monoamine transporter inhibitors from herbal sources. We discovered that bakuchiol analogs isolated from Fructus Psoraleae inhibited monoamine transporter uptake to differing degrees. The bakuchiol analog, Delta3,2-hydroxybakuchiol was the most potent and efficacious reuptake blocker and was thus selected as the candidate target. Monoamine transporter inhibition by Delta3,2-hydroxybakuchiol was more selective for the dopamine transporter (DAT) (IC50=0.58+/-0.1 microM) and norepinephrine transporter (NET) (IC50=0.69+/-0.12 microM) than for the serotonin transporter (SERT) (IC50=312.02+/-56.69 microM). Delta3,2-Hydroxybakuchiol exhibited greater potency (pEC50 for DAT and NET) than bupropion and exhibited similar efficacy (E(max) for DAT and/or NET) to bupropion and GBR12,935. Pharmacokinetically, Delta3,2-hydroxybakuchiol competitively inhibited DAT and NET with partial reversibility and occupied cocaine binding sites. Moreover, Delta3,2-hydroxybakuchiol counteracted 1-methyl-4-phenylpyridinium-induced toxicity in cells expressing DAT with similar efficacy to GBR12,935. In vivo studies showed that Delta3,2-hydroxybakuchiol increased the activity of intact mice and improved the decreased activity of reserpinized mice. In the conditioned place preference test, preference scores in intact mice were unaffected by Delta3,2-hydroxybakuchiol treatment. Bakuchiol analogs, especially Delta3,2-hydroxybakuchiol, are monoamine transporter inhibitors involved in regulating dopaminergic and noradrenergic neurotransmission and may have represented potential pharmacotherapies for disorders such as Parkinson's disease, depression, and cocaine addiction.