Diallyl sulfide inhibits diethylstilbestrol induced DNA damage in human breast epithelial cells (MCF-10A)

Dialyl-sulfide with trans-chalcone prevent breast cancer prohibiting SULT1E1 malregulations and oxidant-stress induced HIF1a-MMPs induction

BACKGROUND

In some breast cancers, altered estrogen-sulfotransferase (SULT1E1) and its inactivation by oxidative-stress modifies E2 levels. Parallelly, hypoxia-inducible tissue-damaging factors (HIF1α) are induced. The proteins/genes expressions of these factors were verified in human-breast-cancer tissues. SULT1E1 inducing-drugs combinations were tested for their possible protective effects.

METHODS

Matrix-metalloproteases (MMP2/9) activity and SULT1E1-HIF1α protein/gene expression (Western-blot/RTPCR) were assessed in breast-cancers versus adjacent-tissues. Oxidant-stress neutralizer, chalcone (trans-1,3-diaryl-2-propen-1-ones) and SULT1E1-inducer pure dialyl-sulfide (garlic; Allium sativum) were tested to prevent cancer causing factors in rat, in-vitro and in-vivo. The antioxidant-enzymes SOD1/catalase/GPx/LDH and matrix-degenerating MMP2/9 activities were assessed (gel-zymogram). Histoarchitecture (HE-staining) and tissue SULT1E1-localization (immuno-histochemistry) were screened. Extensive statistical-analysis were performed.

RESULTS

Human cancer-tissue expresses higher SULT1E1, HIF1α protein/mRNA and lower LDH activity. Increase of MMP2/9 activities commenced tissue damage. However, chalcone and DAS significantly induced SULT1E1 gene/protein, suppressed HIF1α expression, MMP2/9 activities in rat tissues. Correlation and group statistics of t-test suggest significant link of oxidative-stress (MDA) with SULT1E1 (p = 0.006), HIF1α (p = 0.006) protein-expression. The non-protein-thiols showed negative correlation (p = 0.001) with HIF1α. These proteins and SULT1E1-mRNA expressions were significantly higher in tumor (p < 0.05). Correlation data suggest, SULT1E1 is correlated with non-protein-thiols.

CONCLUSIONS

Breast cancers associate with SULT1E1, HIF1α and MMPs deregulations. For the first time, we are revealing that advanced cancer tissue with elevated SULT1E1-protein may reactivate in a reducing-state initiated by chalcone, but remain dormant in an oxidative environment. Furthermore, increased SULT1E1 protein synthesis is caused by DAS-induced mRNA expression. The combined effects of the drugs might decrease MMPs and HIF1α expressions. Further studies are necessary.

From Natural Sources to Synthetic Derivatives: The Allyl Motif as a Powerful Tool for Fragment-Based Design in Cancer Treatment

Since the beginning of history, natural products have been an abundant source of bioactive molecules for the treatment of different diseases, including cancer. Many allyl derivatives, which have shown anticancer activity both in vitro and in vivo in a large number of cancers, are bioactive molecules found in garlic, cinnamon, nutmeg, or mustard. In addition, synthetic products containing allyl fragments have been developed showing potent anticancer properties. Of particular note is the allyl derivative 17-AAG, which has been evaluated in Phase I and Phase II/III clinical trials for the treatment of multiple myeloma, metastatic melanoma, renal cancer, and breast cancer. In this Perspective, we compile extensive literature evidence with descriptions and discussions of the most recent advances in different natural and synthetic allyl derivatives that could generate cancer drug candidates in the near future.

Diallyl sulfide protects against dilated cardiomyopathy via inhibition of oxidative stress and apoptosis in mice

Cytochrome P450 family 2 subfamily E member 1 (CYP2E1) is a member of the cytochrome P450 enzyme family and catalyzes the metabolism of various substrates. CYP2E1 is upregulated in multiple heart diseases and causes damage mainly via the production of reactive oxygen species (ROS). In mice, increased CYP2E1 expression induces cardiac myocyte apoptosis, and knockdown of endogenous CYP2E1 can attenuate the pathological development of dilated cardiomyopathy (DCM). Nevertheless, targeted inhibition of CYP2E1 via the administration of drugs for the treatment of DCM remains elusive. Therefore, the present study aimed to investigate whether diallyl sulfide (DAS), a competitive inhibitor of CYP2E1, can be used to inhibit the development of the pathological process of DCM and identify its possible mechanism. Here, cTnT^R141W transgenic mice, which developed typical DCM phenotypes, were used. Following treatment with DAS for 6 weeks, echocardiography, histological analysis and molecular marker detection were conducted to investigate the DAS-induced improvement on myocardial function and morphology. Biochemical analysis, western blotting and TUNEL assays were used to detected ROS production and myocyte apoptosis. It was found that DAS improved the typical DCM phenotypes, including chamber dilation, wall thinning, fibrosis, poor myofibril organization and decreased ventricular blood ejection, as determined using echocardiographic and histopathological analyses. Furthermore, the regulatory mechanisms, including inhibition both of the oxidative stress levels and the mitochondria-dependent apoptosis pathways, were involved in the effects of DAS. In particular, DAS showed advantages in terms of improved chamber dilation and dysfunction in model mice, and the improvement occurred in the early stage of the treatment compared with enalaprilat, an angiotensin-converting enzyme inhibitor that has been widely used in the clinical treatment of DCM and HF. The current results demonstrated that DAS could protect against DCM via inhibition of oxidative stress and apoptosis. These findings also suggest that inhibition of CYP2E1 may be a valuable therapeutic strategy to control the development of heart diseases, especially those associated with CYP2E1 upregulation. Moreover, the development of DAS analogues with lower cytotoxicity and metabolic rate for CYP2E1 may be beneficial.

Diallyl Sulfide-Mediated Modulation of the Fatty Acid Synthase (FASN) Leads to Cancer Cell Death in BaP-Induced Lung Carcinogenesis in Swiss Mice

Purpose

Diallyl sulfide (DAS), one of the organo-sulfur secondary metabolites in garlic, has been shown to inhibit the proliferation of cancer cells. The present study aimed to evaluate the mechanism of DAS in the prevention of benzo[a]pyrene (BaP)-induced lung cancer in a murine model.

Materials and Methods

The mice were exposed to 50 mg/kg of BaP twice a week for 4 weeks in order to induce lung carcinoma. Pretreatment of mice with DAS (100 mg/kg) was started 2 weeks before BaP exposure and further continued for 21 weeks. The effect of DAS and BaP was evaluated by studying various parameters in the serum and tissues of the treated or untreated BaP-exposed mice.

Results

The histopathological findings demonstrated that DAS prevented the progression of malignant lung cancer and metastasis in the liver. A significant drop was observed in BaP-induced tumor marker enzymes (ADA, AHH, γ-GT, LDH) in the serum of the mice treated with DAS. Moreover, DAS treatment resulted in the recovery of antioxidant enzymes, SOD and CAT, in BaP-exposed mice. The induction of apoptosis and the destruction of cellular ROS were detected in cancer cells from the mice pre-treated with DAS. The immunohistochemical analysis revealed the up-regulation of fatty acid synthase (FASN) in the lungs and liver tissues of BaP-exposed mice and the treatment with DAS inhibited FASN expression.

Conclusion

The findings of the present study indicated that DAS-induced apoptosis is strongly associated with the downregulation of FASN in tumor tissues. To the best of our knowledge, this is the first study that describes the role of FASN in BaP-induced lung carcinogenesis.

Comparative Quantitative Toxicology and QSAR Modeling of the Haloacetonitriles: Forcing Agents of Water Disinfection Byproduct Toxicity

The haloacetonitriles (HANs) is an emerging class of nitrogenous-disinfection byproducts (N-DBPs) present in disinfected drinking, recycled, processed wastewaters, and reuse waters. HANs were identified as primary forcing agents that accounted for DBP-associated toxicity. We evaluated the toxic characteristics of iodoacetonitrile (IAN), bromoacetonitrile (BAN), dibromoacetonitrile (DBAN), bromochloroacetonitrile (BCAN), tribromoacetonitrile (TBAN), chloroacetonitrile (CAN), dichloroacetonitrile (DCAN), trichloroacetonitrile (TCAN), bromodichloroacetonitrile (BDCAN), and chlorodibromoacetonitrile (CDBAN). This research generated the first quantitative, comparative analyses on the mammalian cell cytotoxicity, genotoxicity and thiol reactivity of these HANs. The descending rank order for HAN cytotoxicity was TBAN ≈ DBAN > BAN ≈ IAN > BCAN ≈ CDBAN > BDCAN > DCAN ≈ CAN ≈ TCAN. The rank order for genotoxicity was IAN ≈ TBAN ≈ DBAN > BAN > CDBAN ≈ BDCAN ≈ BCAN ≈ CAN ≈ TCAN ≈ DCAN. The rank order for thiol reactivity was TBAN > BDCAN ≈ CDBAN > DBAN > BCAN > BAN ≈ IAN > TCAN. These toxicity metrics were associated with membrane permeability and chemical reactivity. Based on their physiochemical parameters and toxicity metrics, we developed optimized, robust quantitative structure activity relationship (QSAR) models for cytotoxicity and for genotoxicity. These models can predict cytotoxicity and genotoxicity of novel HANs prior to analytical biological evaluation.

Mechanisms underlying effect of the mycotoxin cytochalasin B on induction of cytotoxicity, modulation of cell cycle, Ca2+ homeostasis and ROS production in human breast cells

Cytochalasin B, a cell-permeable mycotoxin isolated from the fungus Phoma spp., shows a wide range of biological effects, among which its potent antitumor activity has raised great interests in different models. However, the cytotoxic activity of cytochalasin B and its underlying mechanisms have not been elucidated in breast cells. This study examined the effect of cytochalasin B on MCF 10A human breast epithelial cells and ZR-75-1 human breast cancer cells. Cytochalasin B (10-20μM) concentration-dependently induced cytotoxicity, cell cycle arrest, and [Ca²⁺]_i rises in ZR-75-1 cells but not in MCF 10A cells. In ZR-75-1 cells, cytochalasin B triggered G2/M phase arrest through the modulation of CDK1, cyclin B1, p53, p27 and p21 expressions. The Ca²⁺ signal response induced by cytochalasin B was reduced by removing extracellular Ca²⁺ and was inhibited by the store-operated Ca²⁺ channel blocker 2-APB and SKF96365. In Ca²⁺-free medium, cytochalasin B induced Ca²⁺ release through thapsigargin-sensitive endoplasmic reticulum stores. Moreover, cytochalasin B increased H₂O₂ levels but reduced GSH levels. The apoptotic effects evoked by cytochalasin B were partially inhibited by prechelating cytosolic Ca²⁺ with BAPTA-AM and the antioxidant NAC. Together, in ZR-75-1 cells but not in MCF 10A cells, cytochalasin B activated Ca²⁺-associated mitochondrial apoptotic pathways that involved G2/M phase arrest and ROS signaling. Furthermore, cytochalasin B induced [Ca²⁺]_i rises by releasing Ca²⁺ from the endoplasmic reticulum and causing Ca²⁺ influx through 2-APB or SKF96365-sensitive store-operated Ca²⁺ entry. Our findings provide new insights into the possible application of cytochalasin B in human breast cancer therapy.

Spices for Prevention and Treatment of Cancers

Spices have been widely used as food flavorings and folk medicines for thousands of years. Numerous studies have documented the antioxidant, anti-inflammatory and immunomodulatory effects of spices, which might be related to prevention and treatment of several cancers, including lung, liver, breast, stomach, colorectum, cervix, and prostate cancers. Several spices are potential sources for prevention and treatment of cancers, such as Curcuma longa (tumeric), Nigella sativa (black cumin), Zingiber officinale (ginger), Allium sativum (garlic), Crocus sativus (saffron), Piper nigrum (black pepper) and Capsicum annum (chili pepper), which contained several important bioactive compounds, such as curcumin, thymoquinone, piperine and capsaicin. The main mechanisms of action include inducing apoptosis, inhibiting proliferation, migration and invasion of tumors, and sensitizing tumors to radiotherapy and chemotherapy. This review summarized recent studies on some spices for prevention and treatment of cancers, and special attention was paid to bioactive components and mechanisms of action.

Diallyl Sulfide: Potential Use in Novel Therapeutic Interventions in Alcohol, Drugs, and Disease Mediated Cellular Toxicity by Targeting Cytochrome P450 2E1

Diallyl sulfide (DAS) and other organosulfur compounds are chief constituents of garlic. These compounds have many health benefits, as they are very efficient in detoxifying natural agents. Therefore, these compounds may be useful for prevention/treatment of cancers. However, DAS has shown appreciable allergic reactions and toxicity, as they can also affect normal cells. Thus their use as in the prevention and treatment of cancer is limited. DAS is a selective inhibitor of cytochrome P450 2E1 (CYP2E1), which is known to metabolize many xenobiotics including alcohol and analgesic drugs in the liver. CYP2E1-mediated alcohol/drug metabolism produce reactive oxygen species and reactive metabolites, which damage DNA, protein, and lipid membranes, subsequently causing liver damage. Several groups have shown that DAS is not only capable of inhibiting alcohol- and drug-mediated cellular toxicities, but also HIV protein- and diabetes-mediated toxicities by selectively inhibiting CYP2E1 in various cell types. However, due to known DAS toxicities, its use as a treatment modality for alcohol/drug- and HIV/diabetes-mediated toxicity have only limited clinical relevance. Therefore, effort is being made to generate DAS analogs, which are potent and selective inhibitor of CYP2E1 and poor substrate of CYP2E1. This review summarizes current advances in the field of DAS, its anticancer properties, role as a CYP2E1 inhibitor, preventing agent of cellular toxicities from alcohol, analgesic drugs, xenobiotics, as well as, from diseases like HIV and diabetes. Finally, this review also provides insights toward developing novel DAS analogues for chemical intervention of many disease conditions by targeting CYP2E1 enzyme.

Role of dietary bioactive natural products in estrogen receptor-positive breast cancer

Estrogen receptor (ER)-positive breast cancer, including luminal-A and -B, is the most common type of breast cancer. Extended exposure to estrogen is associated with an increased risk of breast cancer. Both ER-dependent and ER-independent mechanisms have been implicated in estrogen-mediated carcinogenesis. The ER-dependent pathway involves cell growth and proliferation triggered by the binding of estrogen to the ER. The ER-independent mechanisms depend on the metabolism of estrogen to generate genotoxic metabolites, free radicals and reactive oxygen species to induce breast cancer. A better understanding of the mechanisms that drive ER-positive breast cancer will help optimize targeted approaches to prevent or treat breast cancer. A growing emphasis is being placed on alternative medicine and dietary approaches toward the prevention and treatment of breast cancer. Many natural products and bioactive compounds found in foods have been shown to inhibit breast carcinogenesis via inhibition of estrogen induced oxidative stress as well as ER signaling. This review summarizes the role of bioactive natural products that are involved in the prevention and treatment of estrogen-related and ER-positive breast cancer.

Diallyl Sulfide and Its Role in Chronic Diseases Prevention

Diallyl sulfide (C₆H₁₀S, DAS) is one of the novel natural organosulfur compounds, which is mostly obtained from the genus Allium plants. Numerous studies have revealed several unique properties of DAS in terms of its health-promoting effects. DAS has proved to be anticancer, antimicrobial, anti-angiogenic, and immunomodulatory like unique functions as demonstrated by the multiple investigations. Diallyl sulfide can also impede oxidative stress and chronic inflammation as suggested by the literature. Studies also explored that DAS could thwart the development of chronic diseases like cancer, neuronal, cardiovascular disease through modulating mechanistic pathways involved in pathogenesis. In this book chapter, we have attempted to give the comprehensive view on DAS about the physiochemical and biological properties, and its preventive role in chronic diseases with a mechanistic overview.