The therapeutic potential of thiocyanate and hypothiocyanous acid against pulmonary infections

Hypothiocyanous acid (HOSCN) is an endogenous oxidant produced by peroxidase oxidation of thiocyanate (SCN-), an ubiquitous sulfur-containing pseudohalide synthesized from cyanide. HOSCN serves as a potent microbicidal agent against pathogenic bacteria, viruses, and fungi, functioning through thiol-targeting mechanisms, independent of currently approved antimicrobials. Additionally, SCN- reacts with hypochlorous acid (HOCl), a highly reactive oxidant produced by myeloperoxidase (MPO) at sites of inflammation, also producing HOSCN. This imparts both antioxidant and antimicrobial potential to SCN-. In this review, we discuss roles of HOSCN/SCN- in immunity and potential therapeutic implications for combating infections.

PR-619, a General Inhibitor of Deubiquitylating Enzymes, Diminishes Cisplatin Resistance in Urothelial Carcinoma Cells through the Suppression of c-Myc: An In Vitro and In Vivo Study

Cisplatin-based chemotherapy is the standard treatment for bladder urothelial carcinoma (UC). Most patients experience chemoresistance, the primary cause of treatment failure, which leads to disease relapse. The underlying mechanism of chemoresistance involves reduced apoptosis. In this study, we investigated the antitumor effect of the deubiquitylating enzyme inhibitor PR-619 in cisplatin-resistant bladder UC. Deubiquitinase (ubiquitin-specific protease 14 (USP14) and USP21) immunohistochemical staining demonstrated that deubiquitination is related to chemoresistance in patients with metastatic UC and may be a target for overcoming chemoresistance. Cytotoxicity and apoptosis were assessed using fluorescence-activated flow cytometry and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium assay, and PR-619 was found to enhance the cytotoxic and apoptotic effects of cisplatin in cisplatin-resistant T24/R cells. Mitigated cisplatin chemoresistance was associated with the concurrent suppression of c-Myc expression in T24/R cells. Moreover, the expression of c-Myc was upregulated in human bladder UC specimens from patients with chemoresistance. Experiments in a xenograft nude mouse model confirmed that PR-619 enhanced the antitumor effects of cisplatin. These results are promising for the development of therapeutic strategies to prevent UC chemoresistance through the combined use of chemotherapeutic agents/deubiquitination inhibitors (PR-619) by targeting the c-Myc pathway.

Deubiquitinase inhibitor PR-619 reduces Smad4 expression and suppresses renal fibrosis in mice with unilateral ureteral obstruction

Deubiquitinating enzymes (DUBs) remove ubiquitin from their substrates and, together with ubiquitin ligases, play an important role in the regulation of protein expression. Although transforming growth factor (TGF)-β1-Smad signaling is a central pathway of renal fibrosis, the role of DUBs in the expression of TGF-β receptors and Smads during the development of renal fibrosis remains unknown. In this study, we investigated whether PR-619, a pan-DUB inhibitor, suppresses fibrosis in mice with unilateral ureteral obstruction (UUO) and TGF-β1-stimulated normal rat kidney (NRK)-49F cells, a rat renal fibroblast cell line. Either the vehicle (dimethyl sulfoxide) or PR-619 (100 μg) was intraperitoneally administered to mice after UUO induction once a day for 7 days. Administration of PR-619 attenuated renal fibrosis with downregulation of mesenchymal markers, extracellular matrix proteins, matrix metalloproteinases, apoptosis, macrophage infiltration, and the TGF-β1 mRNA level in UUO mice. Although type I TGF-β receptor (TGF-βRI), Smad2, Smad3, and Smad4 protein expression levels were markedly increased in mice with UUO, administration of PR-619 suppressed only Smad4 expression but not TGF-βRI, Smad2, or Smad3 expression. PR-619 also had an inhibitory effect on TGF-β1-induced α-smooth muscle actin expression and reduced Smad4 levels in NRK-49F cells. Our results indicate that PR-619 ameliorates renal fibrosis, which is accompanied by the reduction of Smad4 expression.

Comparison of Adaptive Neuroprotective Mechanisms of Sulforaphane and its Interconversion Product Erucin in in Vitro and in Vivo Models of Parkinson's Disease

Several studies suggest that an increase of glutathione (GSH) through activation of the transcriptional nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in the dopaminergic neurons may be a promising neuroprotective strategy in Parkinson's disease (PD). Among Nrf2 activators, isothiocyanate sulforaphane (SFN), derived from precursor glucosinolate present in Brassica vegetables, has gained attention as a potential neuroprotective compound. Bioavailability studies also suggest the contribution of SFN metabolites, including erucin (ERN), to the neuroprotective effects of SFN. Therefore, we compared the in vitro neuroprotective effects of SFN and ERN at the same dose level (5 μM) and oxidative treatment with 6-hydroxydopamine (6-OHDA) in SH-SY5Y cells. The pretreatment of SH-SY5Y cells with SFN recorded a higher (p < 0.05) active nuclear Nrf2 protein (12.0 ± 0.4 vs 8.0 ± 0.2 fold increase), mRNA Nrf2 (2.0 ± 0.3 vs 1.4 ± 0.1 fold increase), total GSH (384.0 ± 9.0 vs 256.0 ± 8.0 μM) levels, and resistance to neuronal apoptosis elicited by 6-OHDA compared to ERN. By contrast, the simultaneous treatment of SH-SY5Y cells with either SFN or ERN and 6-OHDA recorded similar neuroprotective effects with both the isothiocyanates (Nrf2 protein 2.2 ± 0.2 vs 2.1 ± 0.1 and mRNA Nrf2 2.1 ± 0.3 vs 1.9 ± 0.2 fold increase; total GSH 384.0 ± 4.8 vs 352.0 ± 6.4 μM). Finally, in vitro finding was confirmed in a 6-OHDA-PD mouse model. The metabolic oxidation of ERN to SFN could account for their similar neuroprotective effects in vivo, raising the possibility of using vegetables containing a precursor of ERN for systemic antioxidant benefits in a similar manner to SFN.

Hepatic dysfunction induced by 7, 12-dimethylbenz(α)anthracene and its obviation with erucin using enzymatic and histological changes as indicators

The toxicity induced by 7, 12-dimethylbenz(α)anthracene (DMBA) has been widely delineated by a number of researchers. This potent chemical damages many internal organs including liver, by inducing the production of reactive oxygen species, DNA-adduct formation and affecting the activities of phase I, II, antioxidant and serum enzymes. Glucosinolate hydrolytic products like isothiocyanates (ITCs) are well known for inhibiting the DNA-adduct formation and modulating phase I, II enzymes. Sulforaphane is ITC, currently under phase trials, is readily metabolized and inter-converted into erucin upon ingestion. We isolated erucin from Eruca sativa (Mill.) Thell. evaluated its hepatoprotective role in DMBA induced toxicity in male wistar rats. The rats were subjected to hepatic damage by five day regular intraperitoneal doses of DMBA. At the end of the protocol, the rats were euthanized, their blood was collected and livers were processed. The liver homogenate was analyzed for phase I (NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, cytochrome P450, cytochrome P420 and cytochrome b5), phase II (DT diaphorase, glutathione-S-transferase and γ-glutamyl transpeptidase) and antioxidant enzymes (superoxide dismutase, catalase, guaiacol peroxidise, ascorbate peroxidise, glutathione reductase and lactate dehydrogenase). The level of thiobarbituric acid reactive substances, lipid hydroperoxides, conjugated dienes and reduced glutathione in the liver homogenate was also analyzed. The serum was also analyzed for markers indicating hepatic damage (alkaline phosphatase, serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, direct bilirubin and total bilirubin). Erucin provided significant protection against DMBA induced damage by modulating the phase I, II and antioxidant enzymes. The histological evaluation of liver tissue was also conducted, which showed the hepatoprotective role of erucin.

Stereological survey of the ameliorative effects of sulforaphane and quercetin on renal tissue in unilateral ureteral obstruction in rats

Hydrostatic pressure, which is the result of urinary tract blockage, initiates renal injuries. The injuries are characterized by tubular dilatation and/or atrophy, tubular cell death, inflammatory process and progressive interstitial fibrosis with loss of renal parenchyma. The aim of this study was to evaluate the ameliorative effects of sulforaphane and quercetin, the two natural compounds that can be found in vegetables, in unilateral ureteral obstruction (UUO). Three groups of rats underwent surgery to induce UUO. They received distilled water, sulforaphane (500 microg/animal/ day) and quercetin (50 mg/kg/day). Stereological methods were applied in order to obtain accurate, quantitative and comparable data. Less than approximately 4% of renal structures on average remained intact in UUO rats. After the treatment of UUO rats with quercetin, approximately 69%, 32%, 65%, 35% and 41% of the volume of the glomeruli, proximal and distal convoluted tubules (PCT and DCT), Henle's loop and collecting ducts remained intact, respectively (p < 0.01). After the treatment of UUO rats with sulforaphane, approximately 24%, 45%, and 26% of the volume of the PCT, DCT and Henle's loop remained intact, respectively (p < 0.01). After the treatment of UUO rats with quercetin, approximately 71%, 81%, 51%, and 57% of the length of the PCT, DCT, Henle's loop and collecting ducts remained intact, respectively (p < 0.01). After the treatment of UUO rats with sulforaphane, approximately 42% and 41% of the length of the PCT and DCT remained intact, respectively (p < 0.01). Changes in the length of Henle's loop and collecting ducts were not significant. In conclusion, quercetin and sulforaphane were found to be effective in preventing some structural renal damage in the direct obstruction model. Quercetin had a more ameliorative role on renal structures.

Sonic hedgehog signaling inhibition provides opportunities for targeted therapy by sulforaphane in regulating pancreatic cancer stem cell self-renewal

Dysregulation of the sonic hedgehog (Shh) signaling pathway has been associated with cancer stem cells (CSC) and implicated in the initiation of pancreatic cancer. Pancreatic CSCs are rare tumor cells characterized by their ability to self-renew, and are responsible for tumor recurrence accompanied by resistance to current therapies. The lethality of these incurable, aggressive and invasive pancreatic tumors remains a daunting clinical challenge. Thus, the objective of this study was to investigate the role of Shh pathway in pancreatic cancer and to examine the molecular mechanisms by which sulforaphane (SFN), an active compound in cruciferous vegetables, inhibits self-renewal capacity of human pancreatic CSCs. Interestingly, we demonstrate here that Shh pathway is highly activated in pancreatic CSCs and plays important role in maintaining stemness by regulating the expression of stemness genes. Given the requirement for Hedgehog in pancreatic cancer, we investigated whether hedgehog blockade by SFN could target the stem cell population in pancreatic cancer. In an in vitro model, human pancreatic CSCs derived spheres were significantly inhibited on treatment with SFN, suggesting the clonogenic depletion of the CSCs. Interestingly, SFN inhibited the components of Shh pathway and Gli transcriptional activity. Interference of Shh-Gli signaling significantly blocked SFN-induced inhibitory effects demonstrating the requirement of an active pathway for the growth of pancreatic CSCs. SFN also inhibited downstream targets of Gli transcription by suppressing the expression of pluripotency maintaining factors (Nanog and Oct-4) as well as PDGFRα and Cyclin D1. Furthermore, SFN induced apoptosis by inhibition of BCL-2 and activation of caspases. Our data reveal the essential role of Shh-Gli signaling in controlling the characteristics of pancreatic CSCs. We propose that pancreatic cancer preventative effects of SFN may result from inhibition of the Shh pathway. Thus Sulforaphane potentially represents an inexpensive, safe and effective alternative for the management of pancreatic cancer.

Role of 4-hydroxynonenal in chemopreventive activities of sulforaphane

Chemoprevention of cancer via herbal and dietary supplements is a logical approach to combating cancer and currently it is an attractive area of research investigation. Over the years, isothiocyanates, such as sulforaphane (SFN) found in cruciferous vegetables, have been advocated as chemopreventive agents, and their efficacy has been demonstrated in cell lines and animal models. In vivo studies with SFN suggest that in addition to protecting normal healthy cells from environmental carcinogens, it also exhibits cytotoxicity and apoptotic effects against various cancer cell types. Among several mechanisms for the chemopreventive activity of SFN against chemical carcinogenesis, its effect on drug-metabolizing enzymes that cause activation/neutralization of carcinogenic metabolites is well established. Recent studies suggest that SFN exerts its selective cytotoxicity to cancer cells via reactive oxygen species-mediated generation of lipid peroxidation products, particularly 4-hydroxynonenal (HNE). Against the background of the known biochemical effects of SFN on normal and cancer cells, in this article we review the underlying molecular mechanisms responsible for the overall chemopreventive effects of SFN, focusing on the role of HNE in these mechanisms, which may also contribute to its selective cytotoxicity to cancer cells.

Modulation of experimental herpes encephalitis-associated neurotoxicity through sulforaphane treatment

Reactive oxygen species (ROS) produced by brain-infiltrating macrophages and neutrophils, as well as resident microglia, are pivotal to pathogen clearance during viral brain infection. However, unchecked free radical generation is also responsible for damage to and cytotoxicity of critical host tissue bystander to primary infection. These unwanted effects of excessive ROS are combated by local cellular production of antioxidant enzymes, including heme oxygenase-1 (HO-1) and glutathione peroxidase 1 (Gpx1). In this study, we showed that experimental murine herpes encephalitis triggered robust ROS production, as well as an opposing upregulation of the antioxidants HO-1 and Gpx1. This antioxidant response was insufficient to prevent tissue damage, neurotoxicity, and mortality associated with viral brain infection. Previous studies corroborate our data supporting astrocytes as the major antioxidant producer in brain cell cultures exposed to HSV-1 stimulated microglia. We hypothesized that stimulating opposing antioxidative responses in astrocytes, as well as neurons, would mitigate the effects of ROS-mediated neurotoxicity both in vitro and during viral brain infection in vivo. Here, we demonstrate that the addition of sulforaphane, a potent stimulator of antioxidant responses, enhanced HO-1 and Gpx1 expression in astrocytes through the activation of nuclear factor-E2-related factor 2 (Nrf2). Additionally, sulforaphane treatment was found to be effective in reducing neurotoxicity associated with HSV-stimulated microglial ROS production. Finally, intraperitoneal injections of sulforaphane into mice during active HSV infection reduced neuroinflammation via a decrease in brain-infiltrating leukocytes, macrophage- and neutrophil-produced ROS, and MHCII-positive, activated microglia. These data support a key role for astrocyte-produced antioxidants in modulating oxidative stress and neuronal damage in response to viral infection.

Isothiocyanates inhibit psoriasis-related proinflammatory factors in human skin

OBJECTIVE

4-Methylthiobutylisothiocyanate (MTBI), the main rocket (Eruca sativa) seed isothiocyanate (ITC), and its oxidized form, sulforaphane (SFN), were assessed for their potential effects on psoriasis-related factors.

METHODS

MTBI and SFN were evaluated for their effect on mRNA expression and cytokine secretion in vitro in human monocytes and macrophage-like cells and ex vivo in topically treated inflamed human skin. In addition, they were assayed in vivo for morphological changes in topically treated psoriasiform human skin in severe-combined immunodeficient (SCID) mice.

RESULTS

MTBI and SFN contributed to the prevention of inflammation development and reduced ongoing inflammation by downregulating lipopolysaccharide (LPS)-induced mRNA expression of the psoriasis-related cytokines, interleukin (IL)-12/23p40 (25-58 %), tumor necrosis factor (TNF)-α (15-37 %) and IL-6 (25-71 %), in human macrophage-like cells. In monocytes, they tended to act additively on cytokine mRNA and reduced IL-12/23p40 (51 %) secretion. In an ex-vivo inflamed human skin organ culture, MTBI (1 μg/ml) reduced the secretion of IL-1 (39 %) and IL-6 (32 %). Moreover, 2/8 and 3/8 of the MTBI- and SFN-treated psoriasiform SCID mice, respectively, recovered partially or entirely from the psoriasiform process.

CONCLUSIONS

Results from these models indicate the potential of rocket seed ITCs as biological agents in the therapy of psoriasis and inflammation-related skin diseases.

Sulforaphane attenuates hepatic fibrosis via NF-E2-related factor 2-mediated inhibition of transforming growth factor-β/Smad signaling

Sulforaphane (SFN) is a dietary isothiocyanate that exerts chemopreventive effects via NF-E2-related factor 2 (Nrf2)-mediated induction of antioxidant/phase II enzymes, such as heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase 1 (NQO1). This work was undertaken to evaluate the effects of SFN on hepatic fibrosis and profibrotic transforming growth factor (TGF)-β/Smad signaling, which are closely associated with oxidative stress. SFN suppressed TGF-β-enhanced expression of α-smooth muscle actin (α-SMA), a marker of hepatic stellate cell (HSC) activation, and profibrogenic genes such as type I collagen, fibronectin, tissue inhibitor of matrix metalloproteinase (TIMP)-1, and plasminogen activator inhibitor (PAI)-1 in hTERT, an immortalized human HSC line. SFN inhibited TGF-β-stimulated activity of a PAI-1 promoter construct and (CAGA)(9) MLP-Luc, an artificial Smad3/4-specific reporter, in addition to reducing phosphorylation and nuclear translocation of Smad3. Nrf2 overexpression was sufficient to inhibit the TGF-β/Smad signaling and PAI-1 expression. Conversely, knockdown of Nrf2, but not inhibition of HO-1 or NQO1 activity, significantly abolished the inhibitory effect of SFN on (CAGA)(9) MLP-Luc activity. However, inhibition of NQO1 activity reversed repression of TGF-β-stimulated expression of type I collagen by SFN, suggesting the involvement of antioxidant activity of SFN in the suppression of Smad-independent fibrogenic gene expression. Finally, SFN treatment attenuated the development and progression of early stage hepatic fibrosis induced by bile duct ligation in mice, accompanied by reduced expression of type I collagen and α-SMA. Collectively, these results show that SFN elicits an antifibrotic effect on hepatic fibrosis through Nrf2-mediated inhibition of the TGF-β/Smad signaling and subsequent suppression of HSC activation and fibrogenic gene expression.

Therapeutic potential of Nrf2 activators in streptozotocin-induced diabetic nephropathy

OBJECTIVE

To determine whether dietary compounds targeting NFE2-related factor 2 (Nrf2) activation can be used to attenuate renal damage and preserve renal function during the course of streptozotocin (STZ)-induced diabetic nephropathy.

RESEARCH DESIGN AND METHODS

Diabetes was induced in Nrf2(+/+) and Nrf2(-/-) mice by STZ injection. Sulforaphane (SF) or cinnamic aldehyde (CA) was administered 2 weeks after STZ injection and metabolic indices and renal structure and function were assessed (18 weeks). Markers of diabetes including blood glucose, insulin, polydipsia, polyuria, and weight loss were measured. Pathological alterations and oxidative damage in glomeruli were also determined. Changes in protein expression of the Nrf2 pathway, as well as transforming growth factor-β1 (TGF-β1), fibronectin (FN), collagen IV, and p21/WAF1Cip1 (p21) were analyzed. The molecular mechanisms of Nrf2-mediated protection were investigated in an in vitro model using human renal mesangial cells (HRMCs).

RESULTS

SF or CA significantly attenuated common metabolic disorder symptoms associated with diabetes in Nrf2(+/+) but not in Nrf2(-/-) mice, indicating SF and CA function through specific activation of the Nrf2 pathway. Furthermore, SF or CA improved renal performance and minimized pathological alterations in the glomerulus of STZ-Nrf2(+/+) mice. Nrf2 activation reduced oxidative damage and suppressed the expression of TGF-β1, extracellular matrix proteins and p21 both in vivo and in HRMCs. In addition, Nrf2 activation reverted p21-mediated growth inhibition and hypertrophy of HRMCs under hyperglycemic conditions.

CONCLUSIONS

We provide experimental evidence indicating that dietary compounds targeting Nrf2 activation can be used therapeutically to improve metabolic disorder and relieve renal damage induced by diabetes.

Pharmacological targeting of the transcription factor Nrf2 at the basal ganglia provides disease modifying therapy for experimental parkinsonism

Current therapies for motor symptoms of Parkinson's disease (PD) are based on dopamine replacement. However, the disease progression remains unaffected, because of continuous dopaminergic neuron loss. Since oxidative stress is actively involved in neuronal death in PD, pharmacological targeting of the antioxidant machinery may have therapeutic value. Here, we analyzed the relevance of the antioxidant phase II response mediated by the transcription factor NF-E2-related factor 2 (Nrf2) on brain protection against the parkinsonian toxin methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Intraperitoneal administration of the potent Nrf2 activator sulforaphane (SFN) increased Nrf2 protein levels in the basal ganglia and led to upregulation of phase II antioxidant enzymes heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase (NQO1). In wild-type mice, but not in Nrf2-knockout mice, SFN protected against MPTP-induced death of nigral dopaminergic neurons. The neuroprotective effects were accompanied by a decrease in astrogliosis, microgliosis, and release of pro-inflammatory cytokines. These results provide strong pharmacokinetic and biochemical evidence for activation of Nrf2 and phase II genes in the brain and also offer a neuroprotective strategy that may have clinical relevance for PD therapy.

[Sulforaphane--a possible agent in prevention and therapy of cancer]

Sulforaphane (SFN) is an isothiocyanate that is naturally present in cruciferous vegetables, with high concentration in broccoli. The results of the most recent studies indicate multi-targeted sulforaphane actions which may contribute to prevention and therapy of cancer. Protective properties of sulforaphane have been observed in every stage of carcinogenesis. The mechanism of protection against the initiation of carcinogenesis by SFN includes modulation of phase I and II xenobiotic-metabolizing enzymes, as well as direct blocking of specific binding sites of carcinogens with the DNA molecule. As a result, sulforaphane inhibits DNA adduct formation, thus reducing the risk of mutations. Further sulforaphane activity is targeted at cancer cells and prevents their expansion due to regulation of proliferation and induction of differentiation or apoptosis. In vitro studies using various types of cancer cells have revealed the ability of SFN to arrest the cell cycle, particularly in G2/M, while SFN at higher concentration is shown to activate apoptotic pathways. The possible SFN anticancer effect in the progression stage of carcinogenesis has been proved by only a few studies, which provide evidence for its antiangiogenic and antimetastatic influence. Additionally, SFN exhibits anti-inflammatory and antibacterial effects relevant to cancer prevention. Apart from the biological activity of SFN, this review also focuses on its bioavailability and tissue distribution as well as individuals' genetic predispositions as significant factors influencing the potential efficiency of chemoprevention using this compound.

Hexane extract of Raphanus sativus L. roots inhibits cell proliferation and induces apoptosis in human cancer cells by modulating genes related to apoptotic pathway

Raphanus sativus, a common cruciferous vegetable has been attributed to possess a number of pharmacological and therapeutic properties. It has been used in indigenous system of medicine for the treatment of various human ailments in India. This present study evaluated the chemopreventive efficacy of different parts of R. sativus such as root, stem and leaves, extracted with solvents of varying polarity and investigated the molecular mechanism leading to growth arrest and apoptotic cell death in human cancer cell lines. Of the different parts, significant growth inhibitory effect was observed with hexane extract of R. sativus root. Analysis of hexane extract by GC-MS revealed the presence of several isothiocyanates (ITCs) such as 4-(methylthio)-3-butenyl isothiocyanate (MTBITC), 4-(methylthio)-3-butyl isothiocyanate (erucin), 4-methylpentyl isothiocyanate, 4-pentenyl isothiocyanate and sulforaphene. R. sativus root extract induced cell death both in p53 proficient and p53 deficient cell lines through induction of apoptotic signaling pathway regardless of the p53 status of cells. The molecular mechanisms underlying R. sativus-induced apoptosis may involve interactions among Bcl(2) family genes, as evidenced by up-regulation of pro-apoptotic genes and down-regulation of anti-apoptotic genes along with activation of Caspase-3. Our findings present the first evidence that hexane extract of R. sativus root exerts potential chemopreventive efficacy and induces apoptosis in cancer cell lines through modulation of genes involved in apoptotic signaling pathway.

[Therapeutic strategies for Alzheimer disease based on endoplasmic reticulum stress]

The endoplasmic reticulum (ER) stress response is a defense system for dealing with the accumulation of unfolded proteins in the ER lumen. Recent reports have shown that ER stress is involved in the pathology of Alzheimer disease and some neurodegenerative diseases. In a screen for compounds that induce the ER-mediated chaperone BiP/GRP78 (BiP), we identified BiP inducer X (BIX). BIX preferentially induced BiP with slight inductions of GRP94, calreticulin, and CHOP. The induction of BiP mRNA by BIX was mediated by activation of ER stress response elements (ERSEs) upstream of the BiP gene, through the ATF6 pathway. Pretreatment of neuroblastoma cells with BIX reduced cell death induced by ER stress. Intracerebroventricular pretreatment with BIX reduced the area of infarction due to focal cerebral ischemia in mice, good in vivo models of ER stress. In the penumbra of BIX-treated mice, ER stress-induced apoptosis was suppressed, leading to a reduction in the number of apoptotic cells. Considering these results together, it appears that BIX induces BiP to prevent neuronal death by ER stress, suggesting that it may be a potential therapeutic agent for Alzheimer disease and some neurodegerenerative diseases caused by ER stress.

Sulforaphane causes epigenetic repression of hTERT expression in human breast cancer cell lines

BACKGROUND

Sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables, is a common dietary component that has histone deacetylase inhibition activity and exciting potential in cancer prevention. The mechanisms by which SFN imparts its chemopreventive properties are of considerable interest and little is known of its preventive potential for breast cancer.

PRINCIPAL FINDINGS

We found that SFN significantly inhibits the viability and proliferation of breast cancer cells in vitro while it has negligible effects on normal breast cells. Inhibition of telomerase has received considerable attention because of its high expression in cancer cells and extremely low level of expression in normal cells. SFN treatment dose- and time-dependently inhibited human telomerase reverse transcriptase (hTERT), the catalytic regulatory subunit of telomerase, in both MCF-7 and MDA-MB-231 human breast cancer cells. DNA methyltransferases (DNMTs), especially DNMT1 and DNMT3a, were also decreased in SFN-treated breast cancer cells suggesting that SFN may repress hTERT by impacting epigenetic pathways. Down-regulation of DNMTs in response to SFN induced site-specific CpG demethylation occurring primarily in the first exon of the hTERT gene thereby facilitating CTCF binding associated with hTERT repression. Chromatin immunoprecipitation (ChIP) analysis of the hTERT promoter revealed that SFN increased the level of active chromatin markers acetyl-H3, acetyl-H3K9 and acetyl-H4, whereas the trimethyl-H3K9 and trimethyl-H3K27 inactive chromatin markers were decreased in a dose-dependent manner. SFN-induced hyperacetylation facilitated the binding of many hTERT repressor proteins such as MAD1 and CTCF to the hTERT regulatory region. Depletion of CTCF using siRNA reduced the SFN-induced down-regulation of hTERT mRNA transcription in these breast cancer cells. In addition, down-regulation of hTERT expression facilitated the induction of cellular apoptosis in human breast cancer cells.

SIGNIFICANCE

Collectively, our results provide novel insights into SFN-mediated epigenetic down-regulation of telomerase in breast cancer prevention and may open new avenues for approaches to SFN-mediated cancer prevention.

Regulation of ER molecular chaperone prevents bone loss in a murine model for osteoporosis

Endoplasmic reticulum (ER) stress response is important for protein maturation in the ER. Some murine models for bone diseases have provided significant insight into the possibility that pathogenesis of osteoporosis is related to ER stress response of osteoblasts. We examined a possible correlation between osteoporosis and ER stress response. Bone specimens from 8 osteoporosis patients and 8 disease-controls were used for immunohistochemical analysis. We found that ER molecular chaperones, such as BiP (immunoglobulin heavy-chain binding protein) and PDI (protein-disulfide isomerase) are down-regulated in osteoblasts from osteoporosis patients. Based on this result, we hypothesized that up-regulation of ER molecular chaperones in osteoblasts could restore decreased bone formation in osteoporosis. Therefore, we investigated whether treatment of murine model for osteoporosis with BIX (BiP inducer X), selective inducer BiP, could prevent bone loss. We found that oral administration of BIX effectively improves decline in bone formation through the activation of folding and secretion of bone matrix proteins. Considering these results together, BIX may be a potential therapeutic agent for the prevention of bone loss in osteoporosis patients.

Different bone sesitivity to malformations induced by procarbazine in fetal rats

The study aimed at to induce cleft-lip-alveolus-palate (CLAP) applying procarbazine in rat fetuses at the 14(th) day of pregnancy, to supply thiocyanate and/or folic acid sufficient for preventive treatment and subsequently to investigate cleft extent in the palatal area as well as bone maturity. In this animal model, female primiparous inbred rats (LEW.1A) were used. The gravid animals were separated into treatment groups: group K (control), group P (procarbazine), group TP (thiocyanate and procarbazine) and group FTP (folic acid, thiocyanate, procarbazine). The results reveal that procarbazine may induce clefts in the palate area. Clefts occurred most frequently in group TP and mainly comprised subtotal clefts of the posterior secondary palate. As for palatal length, group FTP displayed the longest palate which was significantly different only from group K. A different picture was shown for the secondary palate with group TP displaying the shortest values which were significantly different from those in groups K, P, and FTP. Thus, group TP showed the most marked negative changes both for cleft frequency and palatal length as compared to group K and the other groups. The preventive application of either thiocyanate (TP) or thiocaynate and folic acid combined (group FTP) failed to completely prevent cleft formation in the palate area. In conclusion, a preventive effect on palatal clefts and growth inhibition could not be proved for the vitaminoid thiocyanate.

Molecular basis for chemoprevention by sulforaphane: a comprehensive review

The consumption of cruciferous vegetables has long been associated with a reduced risk in the occurrence of cancer at various sites, including the prostate, lung, breast and colon. This protective effect is attributed to isothiocyanates present in these vegetables, and sulforaphane (SF), present in broccoli, is by far the most extensively studied to uncover the mechanisms behind this chemoprotection. The major mechanism by which SF protects cells was traditionally thought to be through Nrf2-mediated induction of phase 2 detoxification enzymes that elevate cell defense against oxidative damage and promote the removal of carcinogens. However, it is becoming clear that there are multiple mechanisms activated in response to SF, including suppression of cytochrome P450 enzymes, induction of apoptotic pathways, suppression of cell cycle progression, inhibition of angiogenesis and anti-inflammatory activity. Moreover, these mechanisms seem to have some degree of interaction to synergistically afford chemoprevention.

Discovery and development of sulforaphane as a cancer chemopreventive phytochemical

Sulforaphane (SF) is a phytochemical that displays both anticarcinogenic and anticancer activity. SF modulates many cancer-related events, including susceptibility to carcinogens, cell death, cell cycle, angiogenesis, invasion and metastasis. We review its discovery and development as a cancer chemopreventive agent with the intention of encouraging further research on this important compound and facilitating the identification and development of new phytochemicals for cancer prevention.

Keap1 eye on the target: chemoprevention of liver cancer

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, causing nearly 600,000 deaths each year. Increased risk of HCC due to chronic infection with hepatitis B virus (HBV) and exposure to dietary aflatoxins is responsible for many of these deaths. Prevention strategies targeting HBV infection and aflatoxin exposure could dramatically impact the rates of HCC. Universal HBV vaccination programs have begun in some high-risk areas. Strategies to reduce aflatoxin contamination in food stores have also been implemented. However, complete elimination of aflatoxin contamination might not be possible. For this reason, chemoprevention strategies which alter aflatoxin disposition are a practical strategy to reduce the incidence of HCC in populations with high dietary aflatoxin exposure. The mechanisms of aflatoxin-induced hepatocarcinogenesis are well known. This knowledge provides the basis for evaluation of both exposures to aflatoxin, as well as modulation of aflatoxin disposition by chemopreventive agents. Products of aflatoxin DNA damage and toxicity as well as other metabolites can be used as biomarkers to evaluate modulation of aflatoxin disposition. Modulation of aflatoxin disposition can be achieved through induction of conjugating and cytoprotective enzymes. Many of these enzymes are regulated through Kelch ECH-associating protein 1 (Keap1)-NF-E2-related factor 2(Nrf2)-antioxidant response element (ARE) signaling, making this pathway an important molecular target for chemoprevention. Rodent studies have identified several classes of chemopreventive agents which induce cytoprotective genes. These inducers include phenolic antioxidants, dithiolethiones, isothiocyanates, and triterpenoids. Furthermore, clinical interventions have shown that inducers of Keap1-Nrf2- ARE signaling increase cytoprotective enzyme expression, resulting in modulation of aflatoxin disposition. Much work remains to be done in order to take promising chemopreventive agents from preclinical evaluation to application in at-risk populations. However, appropriately designed clinical trials will aid in this process, which can have profound impact on the incidence of HCC.

Reprogramming of keratin biosynthesis by sulforaphane restores skin integrity in epidermolysis bullosa simplex

Epidermolysis bullosa simplex (EBS) is a rare inherited condition in which the epidermis loses its integrity after mechanical trauma. EBS is typified by the dysfunction of intermediate filaments in basal keratinocytes of epidermis. Most cases of EBS are due to mutations in the keratin 5 or 14 gene (K5 and K14), whose products copolymerize to form intermediate filaments in basal keratinocytes. Available treatments for this disorder are only palliative. Here we exploit functional redundancy within the keratin gene family as the basis for therapy. We show that genetic activation of Gli2 or treatment with a pharmacological activator of Nrf2, two transcription factors eliciting distinct transcriptional programs, alleviates the blistering caused by a K14 deficiency in an EBS mouse model, correlating with K17 induction in basal epidermal keratinocytes. Nrf2 induction is brought about by treatment with sulforaphane, a natural product. Sulforaphane thus represents an attractive option for the prevention of skin blistering associated with K14 mutations in EBS.

Sulforaphane as a promising molecule for fighting cancer

A number of natural compounds with inhibitory effects on tumorigenesis have been identified from our diet. Several studies have documented the cancer-preventive activity of a significant number of isothiocyanates (ITCs), the majority of which occur in plants, especially in Cruciferous vegetables. The most characterized ITC is sulforaphane (SFN). SFN has received a great deal of attention because of its ability to simultaneously modulate multiple cellular targets involved in cancer development, including: (i) DNA protection by modulating carcinogen-metabolizing enzymes and blocking the action of mutagens; (ii) inhibition of cell proliferation and induction of apoptosis, thereby retarding or eliminating clonal expansion of initiated, transformed, and/or neoplastic cells; (iii) inhibition of neoangiogenesis, progression of benign tumors to malignant tumors, and metastasis formation. SFN is therefore able to prevent, delay, or reverse preneoplastic lesions, as well as to act on cancer cells as a therapeutic agent. Taking into account this evidence and its favorable toxicological profile, SFN can be viewed as a conceptually promising agent in cancer prevention and/or therapy.

Effect of Prion Decontamination Protocols on Nickel-Titanium Rotary Surfaces

Decontamination of instruments is a prerequisite for their potential reuse but may affect surface integrity. Hence, the effect of prion removal protocols on 7 brands of nickel-titanium files was investigated. Baseline debris scores were determined under magnification after staining with van Gieson's solution. After shaping root canals in vitro, rotaries were mechanically and ultrasonically cleaned followed by immersion for 24 hours in 2 M sodium hydroxide (NaOH), 6 M CH(5)N(3), or 3% sodium hypochlorite (NaOCl); control files were stored dry. After sterilization, files were again stained and evaluated. Two of seven file brands demonstrated significantly higher baseline debris scores compared to final scores. Uniformly, debris could not be completely removed; there were no significant differences among groups. After immersion in NaOCl, 27.8% of instruments showed corrosion; however, no deterioration after immersion in the other solutions was found in the other groups. Regarding corrosion, no significant difference was found between brands. Based on these findings, single use of nickel-titanium rotaries appears beneficial.

Inhibition of 7,12-Dimethylbenz(a)anthracene-Induced Skin Tumorigenesis in C57BL/6 Mice by Sulforaphane Is Mediated by Nuclear Factor E2–Related Factor 2

Sulforaphane, a dietary isothiocyanate, possesses potent chemopreventive effects through the induction of cellular detoxifying/antioxidant enzymes via the transcription factor nuclear factor E2-related factor 2 (Nrf2). To investigate carcinogenesis mechanisms related to the regulation of Nrf2, we examined the tumor incidence and tumor numbers per mouse in Nrf2 wild-type (+/+) and Nrf2 knockout (-/-) mice. 7,12-Dimethylbenz(a)anthracene/12-O-tetradecanoylphorbol-13-acetate treatments resulted in an increase in the incidence of skin tumors and tumor numbers per mouse in both genotypes; however, both indices were markedly higher in Nrf2(-/-) mice as compared with Nrf2(+/+) mice. Western blot analysis revealed that Nrf2 as well as heme oxygenase-1, a protein regulated by Nrf2 were not expressed in skin tumors from mice of either genotype, whereas expression of heme oxygenase-1 in Nrf2(+/+) mice was much higher than that in Nrf2(-/-) mice in nontumor skin samples. Next, we examined the chemopreventive efficacy of sulforaphane in mice with both genotypes. Topical application of 100 nmol of sulforaphane once a day for 14 days prior to 7,12-dimethylbenz(a)anthracene/12-O-tetradecanoylphorbol-13-acetate applications decreased the incidence of skin tumor in the Nrf2(+/+) mice when compared with the vehicle-treated group. Importantly, there was no chemoprotective effect elicited by sulforaphane pretreatment in the Nrf2(-/-) mice group. Taken together, our results show for the first time that Nrf2(-/-) mice are more susceptible to skin tumorigenesis and that the chemopreventive effects of sulforaphane are mediated, at least in part, through Nrf2.

Sulforaphane suppresses angiogenesis and disrupts endothelial mitotic progression and microtubule polymerization

Sulforaphane (SUL), an isothiocyanate derived from broccoli and other cruciferous vegetables, is known to induce phase II detoxification enzymes, disrupt cancer cell microtubule polymerization, and trigger cell cycle arrest in breast and colon cancer cells. Here, we provide the first evidence that SUL also acts to inhibit angiogenesis via suppression of endothelial cell proliferation. Bovine aortic endothelial (BAE) cells were exposed to concentrations of up to 15 microM SUL prior to cell cycle analysis and mitotic index quantification. Within 24 h, 15 microM SUL clearly induced G(2)/M accumulation and pre-metaphase arrest in BAE cells. Moreover, immunofluorescence tubulin staining indicated that this same SUL concentration was efficacious in not only disrupting mitotic progression, but also in perturbing normal polymerization of mitotic (and cytoplasmic) microtubules. Furthermore, daily administration of SUL (100 nmol/day, i.v. for 7 days) to female Balb/c mice bearing VEGF-impregnated Matrigel plugs strongly and significantly (P<0.05) suppressed angiogenesis progression as measured by hemoglobin concentration. Taken together, these findings suggest that the endothelial cell population is a novel target of SUL action both in vitro and in vivo. This mechanism of SUL-induced endothelial microtubule disruption and early mitotic arrest may further discern a potential role of SUL as a chemopreventive agent.

Activation of multiple molecular mechanisms for apoptosis in human malignant glioblastoma T98G and U87MG cells treated with sulforaphane

Glioblastoma is the most malignant and prevalent brain tumor that still remains incurable. Recent studies reported anti-cancer effect of the broccoli-derived compound sulforaphane. We explored the mechanisms of sulforaphane-mediated apoptosis in human glioblastoma T98G and U87MG cells. Wright staining and ApopTag assay confirmed apoptosis in glioblastoma cells treated with sulforaphane. Increase in intracellular free Ca2+ was detected by fura-2 assay, suggesting activation of Ca2+-dependent pathways for apoptosis. Western blotting was used to detect changes in expression of Bax and Bcl-2 proteins resulting in increased Bax:Bcl-2 ratio that indicated a commitment of glioblastoma cells to apoptosis. Upregulation of calpain, a Ca2+-dependent cysteine protease, activated caspase-12 that in turn caused activation of caspase-9. With the increased Bax:Bcl-2 ratio, cytochrome c was released from mitochondria to cytosol for sequential activation of caspase-9 and caspase-3. Increased calpain and caspase-3 activities generated 145 kD spectrin breakdown product and 120 kD spectrin breakdown product, respectively. Activation of caspase-3 also cleaved the inhibitor-of-caspase-activated-DNase. Accumulation of apoptosis-inducing-factor in cytosol suggested caspase-independent pathway of apoptosis as well. Two of the inhibitor-of-apoptosis proteins were downregulated because of an increase in 'second mitochondrial activator of caspases/Direct inhibitor-of-apoptosis protein binding protein with low pI.' Decrease in nuclear factor kappa B and increase in inhibitor of nuclear factor kappa B alpha expression favored the process of apoptosis. Collectively, our results indicated activation of multiple molecular mechanisms for apoptosis in glioblastoma cells following treatment with sulforaphane.

Inhibition of angiogenesis and endothelial cell functions are novel sulforaphane-mediated mechanisms in chemoprevention

Sulforaphane, an aliphatic isothiocyanate, is a known cancer chemopreventive agent. Aiming to investigate antiangiogenic potential of sulforaphane, we here report a potent decrease of newly formed microcapillaries in a human in vitro antiangiogenesis model, with an IC50 of 0.08 micromol/L. The effects of sulforaphane on endothelial cell functions essential for angiogenesis were investigated in HMEC-1, an immortalized human microvascular endothelial cell line. Molecular signaling pathways leading to activation of endothelial cell proliferation and degradation of the basement membrane were analyzed by reverse transcription-PCR. Sulforaphane showed time- and concentration-dependent inhibitory effects on hypoxia-induced mRNA expression of vascular endothelial growth factor and two angiogenesis-associated transcription factors, hypoxia-inducible factor-1alpha and c-Myc, in a concentration range of 0.8 to 25 micromol/L. In addition, the expression of the vascular endothelial growth factor receptor KDR/flk-1 was inhibited by sulforaphane at the transcriptional level. Sulforaphane could also affect basement membrane integrity, as it suppressed transcription of the predominant endothelial collagenase matrix metalloproteinase-2 and its tissue inhibitor of metalloproteinase-2. Migration of HMEC-1 cells in a wound healing assay was effectively prevented by sulforaphane at submicromolar concentrations, and we determined an IC50 of 0.69 micromol/L. In addition, within 6 hours of incubation, sulforaphane inhibited tube formation of HMEC-1 cells on basement membrane matrix at 0.1, 1, and 10 micromol/L concentrations. These effects were not due to inhibition of HMEC-1 cell proliferation; however, after 72 hours of incubation, sulforaphane nonselectively reduced HMEC-1 cell growth with an IC50 of 11.3 micromol/L. In conclusion, we have shown that sulforaphane interferes with all essential steps of neovascularization from proangiogenic signaling and basement membrane integrity to endothelial cell proliferation, migration, and tube formation. These novel antiangiogenic activities of sulforaphane are likely to contribute to its cancer chemopreventive and therapeutic potential.

Chemoprotection by sulforaphane: keep one eye beyond Keap1

Sulforaphane (SFN) is an isothiocyanate found in cruciferous vegetables, with particularly high levels detected in broccoli and broccoli sprouts. Over a decade ago, this phytochemical was identified as a likely chemopreventive agent based on its ability to induce Phase 2 detoxification enzymes, as well as to inhibit Phase 1 enzymes involved in carcinogen activation. Considerable attention has focused on SFN as a 'blocking' agent, with the ability to modulate the Nrf2/Keap1 pathway, but recent evidence suggests that SFN acts by numerous other mechanisms. SFN induces cell cycle arrest and apoptosis in cancer cells, inhibits tubulin polymerization, activates checkpoint 2 kinase, and inhibits histone deacetylase activity. The latter findings suggest that SFN may be effective during the post-initiation stages of carcinogenesis, as a 'suppressing' agent. Moreover, pharmacological administration of SFN may be a promising therapeutic approach to the treatment of cancers, including those characterized by increased inflammation and involving viral or bacterial-related pathologies. The present review discusses the more widely established chemoprotective mechanisms of SFN, but makes the case for additional work on mechanisms that might be of importance during later stages of carcinogenesis, beyond Keap1.

Sulforaphane, an activator of Nrf2, suppresses cellular accumulation of arsenic and its cytotoxicity in primary mouse hepatocytes

Sulforaphane (SFN) is an activator of the transcription factor Nrf2, which plays a critical role in metabolism and excretion of xenobiotics. Exposure of primary mouse hepatocytes to SFN resulted in activation of Nrf2 and significant elevation of protein expressions responsible for excretion of arsenic into extracellular space. Pretreatment with SFN 24 h prior to arsenite exposure reduced not only arsenic accumulation in the cells but also cellular toxicity of this metalloid. Therefore, our findings indicate a potential function of SFN in reducing cellular arsenic levels, thereby diminishing arsenic toxicity.

Sulforaphane enhances aquaporin-4 expression and decreases cerebral edema following traumatic brain injury

Brain edema, the infiltration and accumulation of excess fluid causing an increase in brain tissue volume, often leads to a rise in intracranial pressure and is a key contributor to the morbidity and mortality associated with traumatic brain injury (TBI). The cellular and molecular mechanisms contributing to the development/resolution of TBI-associated brain edema are poorly understood. Aquaporin-4 (AQP4) water channel is expressed at high levels in brain astrocytes, and the bidirectional transport of water through these channels is critical for the maintenance of brain water homeostasis. By using a rodent injury model, we show that TBI decreased AQP4 level in the injury core and modestly increased it in the penumbra region surrounding the core. Postinjury administration of sulforaphane (SUL), an isothiocyanate present in abundance in cruciferous vegetables such as broccoli, attenuated AQP4 loss in the injury core and further increased AQP4 levels in the penumbra region compared with injured animals receiving vehicle. These increases in AQP4 levels were accompanied by a significant reduction in brain edema (assessed by percentage water content) at 3 days postinjury. These findings suggest that the reduction of brain edema in response to SUL administration could be due, in part, to water clearance by AQP4 from the injured brain.

RETRACTED: Application of Sulforaphane: Histopathological Study of Intraportal Transplanted Pancreatic Islets Into Livers of Diabetic Rats

BACKGROUND

Islet cell transplantation is a promising method to restore insulin independence to patients with type 1 diabetes mellitus. A main problem in clinical islet transplantation is the fact that only a small percentage of allogeneic islet-transplanted type 1 diabetic patients can completely omit insulin injections after transplantation. One reason for the impaired survival of islet grafts is aberration of the function of islets due to toxic agents, including oxygen radicals and nitric oxide, which arise during warm or cold ischemic time. Therefore, in clinical islet transplantation, islets have been preserved with a mixture of antioxidants to reduce free radical-mediated damage of transplanted beta cells. Our aim was to examine hepatic tissue after metabolic normalization following intraportal islet transplantation after application of sulforaphane.

MATERIALS AND METHODS

Islets were isolated from pancreata of WAG rats. Sulforaphane (24 mg/kg) was administered 24 hours before isolated islets were transplanted into the liver through the portal vein (1200 +/- 100 per rat). At 9 months after transplantation the animals were killed and liver tissue removed for morphological examination.

RESULTS

This report indicated that the intrahepatic portal vein site was indeed an excellent locus for implantation of free pancreatic islets. The islet grafts developed rich vascularization derived from both venous and arterial sources. The islet cells maintained their structural and functional integrity after implantation.

CONCLUSION

Our results showed that sulforaphane improved islet function in vivo, indicating that combination of a free radical scavenger and an antioxidant (sulforaphane) may be used to increase the effectiveness of islet transplantation.

Pharmacogenomics of cancer chemopreventive isothiocyanate compound sulforaphane in the intestinal polyps of ApcMin/+ mice

Sulforaphane (SFN) is an isothiocyanate that is present in widely consumed vegetables. Previous studies have shown that SFN is effective in preventing carcinogenesis induced by carcinogens in rodents. Recently it was found that SFN could also suppress the growth of intestinal polyps in the ApcMin/+ mouse. In the present study, the acute effect of SFN on the gene expression profile in small intestinal polyps of ApcMin/+ mice using Affymetrix microarray was performed. SFN is a strong inducer for phase II drug metabolizing enzymes, which is believed to contribute to its chemopreventive properties. However, the results show that genes involved in apoptosis, cell growth and maintenance rather than the predicted phase II genes were modulated. The proapoptotic genes including MBD4, TNFR-7 and TNF (ligand)-11 were up-regulated while pro-survival genes including cyclin-D2, integrin-beta1 and Wnt-9A were down-regulated. Interestingly, two genes potentially involved in colorectal carcinogenesis, 15-LOX and COX-2 were found to be increased and decreased, respectively. In conclusion, the results show, for the first time, that chemopreventive agents such as SFN regulate different set of genes involving apoptosis, cell growth/maintenance and inflammation in the small intestinal polyps of ApcMin/+ mice, which could contribute to the overall chemopreventive pharmacological effects.

Sulforaphane reduces infarct volume following focal cerebral ischemia in rodents

Stroke is the third leading cause of death and disability in the United States. As several biochemical mechanisms have been proposed to contribute to stroke pathophysiology, treatments acting on multiple targets may be desirable. Sulforaphane (SUL), a naturally occurring isothiocyanate present in cruciferous vegetables, has been shown to induce the expression of multiple NF-E2-related factor-2 (Nrf2) responsive genes. In the present study, we demonstrate that systemically administered SUL can enter the brain as determined by increased mRNA and protein levels of the Nrf2-responsive gene heme oxygenase 1 (HO-1). Delayed administration (15 min) of a single dose of SUL significantly decreased cerebral infarct volume following focal ischemia, suggesting a potential therapeutic value for this compound.

Sulforaphane halts breast cancer cell growth

Sulforaphane is a chemical found in cruciferous vegetables such as broccoli, sprouts and kale. This compound is a potent inducer of protective enzymes that provide defense against cancer-causing chemicals. Researchers have discovered that sulforaphane can halt human breast cancer cells in their tracks and have identified a new mechanism of action for the compound.

Oral broccoli sprouts for the treatment of Helicobacter pylori infection: a preliminary report

We sought to determine whether orally consumed broccoli sprouts could eradicate Helicobacter pylori infection in infected human volunteers. Helicobacter pylori-positive patients were identified by stool antigen testing or gastric biopsies. Patients consumed broccoli sprouts (14, 28, or 56 g) twice daily for 7 days. We performed stool antigen testing immediately following the completion of treatment (day 8) and at day 35. Urea breath testing was performed on those patients who remained negative at day 35. Patients completed pre- and posttreatment questionnaires regarding symptoms (abdominal discomfort--pain, nausea, bloating), recent medications, and palatability. Nine patients completed the course of treatment and began follow-up testing. Seven of nine (78%) patients were stool antigen negative immediately after the completion of therapy and six remained negative at day 35. Urea breath testing was completed on six patients. Two patients were negative, two positive, and two indeterminate. Endoscopic gastric biopsies were obtained from one patient with an indeterminate breath test and the tissue was negative for H. pylori by immunohistochemical staining. Of the five patients who provided information on pre- and posttreatment symptoms, two reported improvement, one no change, and one reported worsening. Six patients rated the taste of broccoli sprouts from okay to very good; one patient stated they were "not good." Consumption of oral broccoli sprouts was temporally associated with eradication of H. pylori infection in three of nine patients. Most patients found broccoli sprouts palatable. Further studies are needed to determine the optimal dose of broccoli sprouts and whether concomitant proton pump inhibitors or antibiotics might augment the effectiveness.

Do folic acid and thiocyanate have a preventive effect on exogenously induced disturbances of embryonic cranial development?

The preventive influence of folic acid and thiocyanate on procarbazine-induced disturbances of embryonic cranial development was investigated on experimental animals. Low dosages of folic acid or thiocyanate demonstrated no prophylactic effect. When thiocyanate was administered alone, an increased cleft rate was unexpectedly found for the secondary palate. The combined application of folic acid and thiocyanate showed a cleft-prophylactic effect in the secondary palate in addition to growth protection in the primary palate. It can be assumed that thiocyanate has a positive effect on chondral and osseous growth of the palate during the post-sensitive phase of embryogenesis, while in the sensitive phase, it can function as a carrier for teratogenous and toxic substances.

Efficacy of sulforaphane in eradicating Helicobacter pylori in human gastric xenografts implanted in nude mice

Sulforaphane, an isothiocyanate abundant in the form of its glucosinolate precursor in broccoli sprouts, has shown in vitro activity against Helicobacter pylori. We evaluated the effect of sulforaphane in vivo against this bacterium by using human gastric xenografts in nude mice. H. pylori was completely eradicated in 8 of the 11 sulforaphane-treated grafts. This result suggests that sulforaphane might be beneficial in the treatment of H. pylori-infected individuals.

Sulforaphane inhibits growth of a colon cancer cell line

OBJECTIVE

The consumption of cruciferous vegetables has a protective effect on the development of colorectal cancer. The phytochemical Sulforaphane is an isothiocyanate found almost exclusively in cruciferous vegetables. We have studied the effect of Sulforaphane on cell proliferation of an HT-29 colon cancer cell line.

MATERIALS AND METHODS

HT-29 colon cancer cells were cultured in 96-well microtitre plates. Sulforaphane (in concentrations ranging from 0.01 to 0.1 mmol) were added to the wells. Cell proliferation was measured using the colourimetric assay technique.

RESULTS

The proliferation of colon cancer cells was significantly reduced by Sulforaphane at concentrations of >/=0.02 mmol.

CONCLUSION

These findings may help explain the epidemiologically proven protective effect of vegetables against colon cancer.

Antiamoebic activity of benzyl glucosinolate from Lepidium virginicum

In a continuation of our search for potential antiprotozoal agents from plants, we found that a crude extract from the roots of Lepidium virginicum exhibited antiprotozoal activity against Entamoeba histolytica trophozoites (IC(50) of 100.1 micro g/mL). Bioassay-guided fractionation resulted in the isolation of one known glucosinolate responsible for such activity. This compound was identified as benzyl glucosinolate. It showed in vitro activity against Entamoeba histolytica strain HM1-IMSS (IC(50) of 20.4 micro g/mL). The results support the anecdotal reports for the traditional use of L. virginicum roots in the control of diarrhoea and dysentery in the highlands of Chiapas, Mexico.

The effect of indole-3-carbinol and sulforaphane on a prostate cancer cell line

BACKGROUND

Cruciferous vegetable consumption is inversely related to the incidence of prostate cancer. We examined the effect of indole-3-carbinol (I3C) and of sulforaphane (constituents of cruciferous vegetables) on cell proliferation of a PC-3 prostate cancer cell line, in order to observe if an inhibitory effect might be detected in vitro.

METHODS

PC-3 prostate cancer cells were cultured in 96-well microtitre plates. Indole-3-carbinol concentrations ranging from 0.1 mmol/L to 0.8 mmol/L or sulforaphane concentrations ranging from 0.01 mmol/L to 0.06 mmol/L were added to the wells. Cell proliferation was measured by colorimetric assay and results were based on the mean value of triplicate experiments. Data are -presented as medians and interquartile ranges and were analysed using the Mann-Whitney U-test.

RESULTS

Cell proliferation in PC-3 prostate cancer cells was significantly inhibited by I3C and sulforaphane at media concentrations of 0.2 mmol/L and 0.02 mmol/L, respectively.

CONCLUSION

Both compounds inhibited the proliferation of prostate cancer cells in a dose-dependent manner. These findings may help explain the observed protective effect of cruciferous vegetables in relation to prostate cancer.

The effect of a SCN-/H2O2 toothpaste compared to a commercially available triclosan-containing toothpaste on oral hygiene and gingival health -- a 6-month home-use study

OBJECTIVES

The aim of the study was to compare the gingival health benefits of a thiocyanate/carbamide peroxide toothpaste to that of a triclosan toothpaste in home use.

MATERIALS AND METHODS

The study was a two-centre, randomised, double-blind, parallel-group clinical trial, and consisted of a 2-week pre-experimental phase, followed by an experimental period of 6 months. A total of 140 healthy male and female volunteers (70 per group) who had at least 20 natural teeth with no probing depths greater than 5 mm and a mean gingival index (GI) of 1 or more at screening were admitted to the study. The two products were the test toothpaste (RCP) containing 0.5% SCN- (rhodanide), carbamide peroxide (equivalent 0.1% H2O2), and 1450 p.p.m. fluoride, and a control toothpaste (Colgate Total) containing 0.3% triclosan, 2.0% polyvinyl methyl ether maleic acid (PVM/MA), and 1450 p.p.m. fluoride (Triclosan). In the pre-experimental phase, all subjects used a fluoride toothpaste. Plaque (Turesky et al. 1970) and gingivitis (Löe & Silness 1963) were scored prior to beginning the pre-experimental phase, at baseline, and after 6 weeks and 3 and 6 months.

RESULTS

In both the RCP and the Triclosan group, gingival health improved significantly between baseline and the following examinations. Plaque scores decreased significantly between baseline and 6 months in both groups. There were, however, no significant differences between the groups for either gingival index or plaque index.

CONCLUSION

To conclude, this study seems to verify that in normal home use, a toothpaste containing a combination of thiocyanate and carbamide peroxide is as effective in reducing gingival inflammation and supragingival plaque formation as a benchmark control product.

Effects of SCN-/H2O2 combinations in dentifrices on plaque and gingivitis

OBJECTIVES

A 10-week, double-blind, placebo-controlled clinical study on 140 male subjects was conducted to determine the effect on plaque and gingivitis of 5 dentifrices containing various thiocyanate (SCN-)/hydrogen peroxide (H2O2) combinations.

MATERIALS AND METHODS

The dentifrices consisted of a gel base without any detergents or abrasives (placebo, group A) to which SCN- and/or H2O2 were added as follows: 0.1% SCN- (group B), 0.5% SCN- (group C), 0.1% SCN-/0.1% H2O2 (group D), 0.5% SCN-/0.1% H2O2 (group E) and 0.1% H2O2 (group F). A baseline examination was performed in which the Silness and Löe Plaque Index (PI), the Mühlemann and Son Sulcus Bleeding Index (SBI), and the amount of gingival crevicular fluid (GCF) were recorded using the Periotron 6,000 on teeth 16, 12, 24, 36, 32, and 44. The subjects were randomly assigned to either the placebo group (n = 40) or one of the test groups (n = 20) and used their respective dentifrices over a period of 8 weeks. Finally, each group used the placebo for another 2 weeks (wash-out). Re-examinations were performed after 1, 4, and 8 weeks and the 2-week wash-out period employing the clinical parameters used at baseline. Intragroup changes were analyzed with the Wilcoxon signed-ranks test, using the baseline and wash-out points as references. The Mann-Whitney U test was used for comparisons between the treatment groups and the placebo group.

RESULTS

At the 8-week examination, the plaque index in group E (p = 0.017) and group F (p = 0.032) was lower than in the placebo group. The Sulcus Bleeding Index in group F after 1 week was increased (p = 0.023) and the SBI in group E after 8 weeks was reduced (p = 0.047) as compared to the placebo group.

CONCLUSION

The results demonstrated that a dentifrice containing 0.5% SCN- and 0.1% H2O2 but no detergents or abrasives inhibited plaque and decreased gingivitis.

Sulforaphane, a naturally occurring isothiocyanate, induces cell cycle arrest and apoptosis in HT29 human colon cancer cells

Sulforaphane is an isothiocyanate that is present naturally in widely consumed vegetables and has a particularly high concentration in broccoli. This compound has been shown to block the formation of tumors initiated by chemicals in the rat. Although sulforaphane has been proposed to modulate the metabolism of carcinogens, its mechanism of action remains poorly understood. We have previously demonstrated that sulforaphane inhibits the reinitiation of growth and decreases the cellular viability of quiescent human colon carcinoma cells (HT29). Moreover, the weak effect observed on differentiated CaCo2 cells suggests a specific anticancer activity for this compound. Here we investigated the effect of sulforaphane on the growth and viability of HT29 cells during their exponentially growing phase. We observed that sulforaphane induced a cell cycle arrest in a dose-dependent manner, followed by cell death. This sulforaphane-induced cell cycle arrest was correlated with an increased expression of cyclins A and B1. Moreover, we clearly demonstrated that sulforaphane induced cell death via an apoptotic process. Indeed, a large proportion of treated cells display the following: (a) translocation of phosphatidylserine from the inner layer to the outer layer of the plasma membrane; (b) typical chromatin condensation; and (c) ultrastructural modifications related to apoptotic cell death. We also showed that the expression of p53 was not changed in sulforaphane-treated cells. In contrast, whereas bcl-2 was not detected, we observed increased expression of the proapoptotic protein bax, the release of cytochrome c from the mitochondria to the cytosol, and the proteolytic cleavage of poly(ADP-ribose) polymerase. In conclusion, our results strongly suggest that in addition to the activation of detoxifying enzymes, induction of apoptosis is also involved in the sulforaphane-associated chemoprevention of cancer.

Oral pharmacological treatments for parasitic diseases of rainbow trout Oncorhynchus mykiss. II. Gyrodactylus sp

A total of 24 drugs were evaluated as regards their efficacy for oral treatment of gyrodactylosis in rainbow trout Oncorhynchus mykiss. In preliminary trials, all drugs were supplied to infected fish at 40 g per kg of feed for 10 d. Twenty-two of the drugs tested (aminosidine, amprolium, benznidazole, bithionol, chloroquine, diethylcarbamazine, flubendazole, levamisole, mebendazole, metronidazole, niclosamide, nitroxynil, oxibendazole, parbendazole, piperazine, praziquantel, ronidazole, secnidazole, tetramisole, thiophanate, toltrazuril and trichlorfon) were ineffective. Triclabendazole and nitroscanate completely eliminated the infection. Triclabendazole was effective only at the screening dosage (40 g per kg of feed for 10 d), while nitroscanate was effective at dosages as low as 0.6 g per kg of feed for 1 d.