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Despite increasing evidences has highlighted the importance of mitochondria-lipid droplet (LD) coupling in maintaining lipid homeostasis, little progress in unraveling the role of mitochondria-LD coupling in hepatic lipid metabolism has been made. Additionally, diallyl disulfide (DADS), a garlic organosulfur compound, has been proposed to prevent hepatic steatosis; however, no studies have focused on the molecular mechanism to date. To address these gaps, this study investigated the systemic control mechanisms of mitochondria-LD coupling regulating hepatic lipid metabolism, and also explored their function in the process of DADS alleviating hepatic steatosis. To this end, an animal model of lipid metabolism, yellow catfish Pelteobagrus fulvidraco were fed four different diets (control, high-fat, DADS and high-fat + DADS diet) in vivo for 8 weeks; in vitro experiments were conducted to inhibit Mfn2/Atgl-mediated mitochondria-LD coupling in isolated hepatocytes. The key findings are: (1) the activations of hepatic LDs lipolysis and mitochondrial β-oxidation are likely the major drivers for DADS alleviating hepatic steatosis; (2) the underlying mechanism is that DADS enhances mitochondria-LD coupling by promoting the interaction between mitochondrion-localized Mfn2 with LD-localized Atgl, which facilitates the hepatic LDs lipolysis and the transfer of fatty acids (FAs) from LDs to mitochondria for subsequent β-oxidation; (3) Mfn2-mediated mitochondrial fusion facilitates mitochondria to form more PDM, which possess higher β-oxidation capacity in hepatocytes. Significantly, the present research unveils a previously undisclosed mechanism by which Mfn2/Atgl-mitochondria-LD coupling relieves hepatic LDs accumulation, which is a conserved strategy from fish to tetrapod. This study provides another dimension for mitochondria-LD coupling and opens up new avenues for the therapeutic interventions in hepatic steatosis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Heavy metals can cause serious health problems that affect different organs. Cadmium (Cd) is an environmental contaminant known for its toxicological consequences on different organs. Hepatotoxicity is a serious effect of exposure to Cd with oxidative stress (OS) and inflammation playing a central role. Diallyl disulfide (DADS), an organo-sulfur compound found in garlic, is known for its cytoprotective and antioxidant effects. In this study, the effect of DADS on Cd-induced inflammation, oxidative stress and liver injury was investigated., Methods: DADS was supplemented for 14 days via oral gavage, and a single intraperitoneal dose of Cd (1.2 mg/kg body weight) was administered to rats on day 7. Blood and liver samples were collected at the end of the experiment for analyses., Results: Cd administration resulted in remarkable hepatic dysfunction, degenerative changes, necrosis, infiltration of inflammatory cells, collagen deposition and other histopathological alterations. Cd increased liver malondialdehyde (MDA) and nitric oxide (NO) ( p < 0.001), upregulated toll-like receptor (TLR)-4, nuclear factor-kappaB (NF-κB), pro-inflammatory mediators, and caspase-3 ( p < 0.001) whereas decreased glutathione (GSH) and antioxidant enzymes ( p < 0.001). Cd downregulated peroxisome proliferator activated receptor gamma (PPARγ), a transcription factor involved in inflammation and OS suppression ( p < 0.001). DADS ameliorated liver injury and tissue alterations, attenuated OS and apoptosis, suppressed TLR-4/NF-κB signaling, and enhanced antioxidants. In addition, DADS upregulated PPARγ in the liver of Cd-administered rats., Conclusions: DADS is effective against Cd-induced hepatotoxicity and its beneficial effects are linked to suppression of inflammation, OS and apoptosis and upregulation of PPARγ. DADS could be valuable to protect the liver in individuals at risk of Cd exposure, pending further studies to elucidate other underlying mechanism(s)., (© 2024 The Author(s). Published by IMR Press.)

Diallyl disulfide (DADS), an organic component of allicin abstracted from garlic, possesses multi-target antitumor activity. DJ-1 performs a vital function in promoting AKT aberrant activation via down-regulating phosphatase and tensin homologue (PTEN) in tumors. It is unknown the involvement of DJ-1 in epithelial-mesenchymal transition (EMT) of gastric cancer (GC) cells. The purpose of this study is to investigate whether diallyl disulfide (DADS) intervenes in the role of DJ-1 in GC. Based on the identification that the correlation between high DJ-1 and low PTEN expression in GC was implicated in clinical progression, we illuminated that down-regulation of DJ-1 by DADS aided in an increase in PTEN expression and a decrease in phosphorylated AKT levels, which was in line with the results manifested in the DJ-1 knockdown and overexpressed cells, concurrently inhibiting proliferation, EMT, migration, and invasion. Furthermore, the antagonistic effects of DADS on DJ-1 were observed in in vivo experiments. Additionally, DADS mitigated the DJ-1-associated drug resistance. The current study revealed that DJ-1 is one of potential targets for DADS, which hopefully provides a promising strategy for prevention and adjuvant chemotherapy of GC., (© 2024 Wiley Periodicals LLC.)

Environmental pollution, virus infection, allergens, and other factors may cause respiratory disease, which could be improved by dietary therapy. Allium species are common daily food seasoning and have high nutritional and medical value. Diallyl disulfide (DADS) is the major volatile oil compound of Allium species. The present study aims to explore the preventive effect and potential mechanism of DADS on pulmonary fibrosis. C57BL/6J mice were intratracheally injected with bleomycin (BLM) to establish pulmonary fibrosis and then administrated with DADS. Primary lung fibroblasts or A549 were stimulated with BLM, followed by DADS, farnesoid X receptor (FXR) agonist (GW4064), yes-associated protein 1 (YAP1) inhibitor (verteporfin), or silencing of FXR and YAP1. In BLM-stimulated mice, DADS significantly ameliorated histopathological changes and interleukin-1β levels in bronchoalveolar lavage fluid. DADS decreased fibrosis markers, HIF-1α, inflammatory cytokines, and epithelial-mesenchymal transition in pulmonary mice and activated fibroblasts. DADS significantly enhanced FXR expression and inhibited YAP1 activation, which functions as GW4064 and verteporfin. A deficiency of FXR or YAP1 could result in the increase of these two protein expressions, respectively. DADS ameliorated extracellular matrix deposition, hypoxia, epithelial-mesenchymal transition, and inflammation in FXR or YAP1 knockdown A549. Taken together, targeting the crosstalk of FXR and YAP1 might be the potential mechanism for DADS against pulmonary fibrosis. DADS can serve as a potential candidate or dietary nutraceutical supplement for the treatment of pulmonary fibrosis., (© 2024 John Wiley & Sons Ltd.)

Diallyl disulfide (DADS), one of the main components of garlic, is well known to have anticancer effects on multiple cancers. However, its efficacy in treating multiple myeloma (MM) is yet to be determined. We explored the effects of DADS on MM cells and investigated the synergistic effects of DADS when combined with five anti-MM drugs, including melphalan, bortezomib, carfilzomib, doxorubicin, and lenalidomide. We analyzed cell viability, cell apoptosis, and DNA damage to determine the efficacy of DADS and the drug combinations. Our findings revealed that DADS induces apoptosis in MM cells through the mitochondria-dependent pathway and increases the levels of γ-H2AX, a DNA damage marker. Combination index (CI) measurements indicated that the combination of DADS with melphalan has a significant synergistic effect on MM cells. This was further confirmed by the increases in apoptotic cells and DNA damage in MM cells treated with the two drug combinations compared with those cells treated with a single drug alone. The synergy between DADS and melphalan was also observed in primary MM cells. Furthermore, mechanistic investigations showed that DADS decreases reduced glutathione (GSH) levels and increases reactive oxygen species (ROS) production in MM cells. The addition of GSH is effective in neutralizing DADS cytotoxicity and inhibiting the synergy between DADS and melphalan in MM cells. Taken together, our study highlights the effectiveness of DADS in treating MM cells and the promising therapeutic potential of combining DADS and melphalan for MM treatment., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: Diallyl disulfide (DADS) is a natural organosulfur compound found in garlic and related plants with various pharmacologic effects. However, whether DADS improves obesity-induced insulin resistance (IR) and its underlying mechanisms remain unclear. The aim of this study was to investigate the effects of DADS on systemic IR in high-fat diet-induced obese mice., Methods: To induce obesity, 8-wk-old male C57BL/6J mice were fed a high-fat diet (60% fat/kcal). The mice were assigned to three weight-matched groups: control (CON, n = 8), low-dose DADS (DADS-L, n = 8), and high-dose DADS (DADS-H, n = 9). The treated mice were orally administered DADS (25 or 100 mg/kg) 5 d/wk for 8 wk. At 15 wk of age, an intraperitoneal glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed. Twenty-four hours after the final administration of DADS, epididymal fat and the liver were sampled after a 5-h fast., Results: DADS administration significantly attenuated body and fat weight gains during the experimental period. Additionally, systemic IR, as evaluated by ITT, was significantly improved by DADS administration in a dose-dependent manner. High-dose DADS administration significantly decreased liver triacylglycerol levels. Moreover, high-dose DADS administration decreased the c-Jun N-terminal kinase (JNK) phosphorylation and significantly increased heat shock protein 72 expression in the liver., Conclusions: The results of this study suggested that DADS administration alleviated systemic IR in obese mice. This may be associated with decreased hepatic fat accumulation and a heat shock protein 72-mediated decrease in JNK activity in the liver., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Previous studies have demonstrated that diallyl disulfide (DADS) exhibits potent anti-tumor activity. However, the pharmacological actions of DADS in inhibiting the growth of colorectal cancer (CRC) cells have not been clarified. Herein, we show that DADS treatment impairs the activation of the pentose phosphate pathway (PPP) to decrease PRPP (5-phosphate ribose-1-pyrophosphate) production, enhancing DNA damage and cell apoptosis, and inhibiting the growth of CRC cells. Mechanistically, DADS treatment promoted POU2F1 K48-linked ubiquitination and degradation by attenuating the PI3K/AKT signaling to up-regulate TRIM21 expression in CRC cells. Evidently, TRIM21 interacted with POU2F1, and induced the K272 ubiquitination of POU2F1. The effects of DADS on the enhanced K272 ubiquitination of POU2F1, the PPP flux, PRPP production, DNA damage and cell apoptosis as well as the growth of CRC tumors in vivo were significantly mitigated by TRIM21 silencing or activating the PI3K signaling in CRC cells. Conversely, the effects of DADS were enhanced by TRIM21 over-expression or inhibiting the PI3K/AKT signaling in CRC cells. Collectively, our findings reveal a novel mechanism by which DADS suppresses the growth of CRC by promoting POU2F1 ubiquitination, and may aid in design of novel therapeutic intervention of CRC., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Hymenolepis nana, a parasitic tapeworm distributed worldwide, is very prevalent in countries with poor sanitary conditions. Garlic is widely used as a seasoning and medicinal plant all over the world, and its derivatives have proven anti-microbial and anti-inflammatory effects. Our study explored the cestocidal and therapeutic effects of allicin derivatives against H. nana in vitro and in vivo. Worms taken from a host were cultured in vitro, and the effects of allyl sulfide (DAS), allyl disulfide (DADS) and dimethyl sulfoxide (DMSO) treatments were observed. Male BALB/c mice were then fed eggs to produce infection, given drugs for ten days and dissected. The results of this study showed that DADS in garlic exhibited good cestocidal effects in vitro and in vivo. DADS and DATS reduced motility, induced mortality and damaged body segments of worms in vitro. In vivo, the number of worms in the low-dose and high-dose DADS groups was significantly less than the infected control group. DADS effected cytokine changes in BALB/c mice after infection. IFN-γ increased, IL-2, 4, 6 and 13 decreased, and IL-5, 10 and IL-12 p70 did not change significantly. As a medicinal plant, garlic has many active ingredients that can developed as anti-microbial or parasite-related drugs., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interest., (Copyright © 2022. Published by Elsevier B.V.)

Aims: Hepatocellular carcinoma (HCC) is considered one of the main causes of cancer-related death globally. Combination therapy targeting different pathways can improve the efficacy of HCC management. Mitofusin 2 (Mfn2), a mitochondrial fusion protein, and a tissue inhibitor of matrix metalloproteinase 3 (Timp-3) were found to be downregulated in various cancers, including HCC. Our study aimed to evaluate the possible antineoplastic effect of a novel combination in the treatment of HCC through targeting mitochondrial fusion and metastatic proteins., Main Methods: HCC induction was performed using a single intraperitoneal dose of diethylnitrosamine (200 mg/kg), followed by adding phenobarbital sodium (0.05%) to the drinking water for successive 18 weeks. Then, leflunomide (LF, 10 mg/kg) was administered orally for 28 days. Diallyl disulfide (DADS, 50 mg/kg) was also given orally for 28 days, either alone or in combination with LF., Key Findings: Treatment with LF or DADS could alleviate the HCC- induced histological and biochemical variations, including liver enzyme activities (ALT, AST), alpha-fetoprotein, Bax, cyclin D1, Ki67, malondialdehyde, and reduced glutathione. They could shift the mitochondrial dynamics toward mitochondrial fusion through upregulating the expression of Mfn2 and also exhibited antimetastatic activity through upregulating the expression of Timp-3 and decreasing hepatic MMP9 content., Significance: the treatment with a combination of LF and DADS displayed a more potent effect than the treatment with each drug alone. Our results suggest that the combined use of LF and a naturally occurring DADS can be used as a promising novel combination in managing HCC., (Copyright © 2022 Elsevier Inc. All rights reserved.)

We investigated whether diallyl disulfide (DADS) has protective effects against 1,3-dichloro-2-propanol (1,3-DCP)-induced hepatotoxicity and oxidative damage in rats and HepG2 cells. DADS was administered to rats once daily for 7 days at doses of 30 and 60 mg/kg/day. One hour after the final DADS treatment, the rats were administered 90 mg/kg 1,3-DCP to induce acute hepatotoxicity. DADS treatment significantly suppressed the increase in serum aminotransferase levels induced by 1,3-DCP administration, and reduced histopathological alterations in the liver. DADS treatment reduced 1-3-DCP-induced apoptotic changes in the liver, as revealed by terminal deoxynucleotidyl transferase dUTP nick end labeling staining and immunohistochemistry for caspase-3. DADS treatment competitively inhibited or reduced cytochrome p450 2E1 (CYP2E1) expression, which is involved in the metabolic activation of 1,3-DCP, and enhanced antioxidant properties. Furthermore, DADS treatment inhibited phosphorylation of mitogen-activated protein kinases (MAPKs) and apoptotic signaling. In in vitro experiments, MAPKs inhibitors reduced the expression of Bax/Bcl-2/Caspase 3 signaling, which effects were more significant in co-treated cells with DADS and MAPKs inhibitors. In conclusion, the protective effect of DADS against 1,3-DCP-induced hepatotoxicity may be related to blocking the metabolic activation of 1,3-DCP by suppressing CYP2E1 expression, inducing antioxidant enzyme activity, and reducing apoptotic activity by inhibiting phosphorylation of MAPKs., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Diallyl disulfide (DADS), a garlic extract also known as allicin, has been reported to have numerous biological activities, including anticancer, antifungal, and inflammation-inhibiting activities, among others. Although many studies have assessed whether DADS can treat Candida albicans infection in vitro , its in vivo function and the underlying mechanism are still not clear. Accumulated evidence has implicated the gut microbiota as an important factor in the colonization and invasion of C. albicans . Thus, this study aimed to identify the mechanism by which DADS ameliorates dextran sulfate (DSS)-induced intestinal C. albicans infection based on the systematic analysis of the gut microbiota and metabolomics in mice. Here, we determined the body weight, survival, colon length, histological score, and inflammatory cytokine levels in the serum and intestines of experimental mice. Fecal samples were collected for gut microbiota and metabolite analysis by 16S rRNA gene sequencing and LC-MS metabolomics, respectively. DADS significantly alleviated DSS-induced intestinal C. albicans infection and altered the gut microbial community structure and metabolic profile in the mice. The abundances of some pathogenic bacteria, such as Proteobacteria , Escherichia-Shigella , and Streptococcus , were notably decreased after treatment with DADS. In contrast, SCFA-producing bacteria, namely, Ruminiclostridium , Oscillibacter , and Ruminococcaceae&#95;UCG-013 , greatly increased in number. The perturbance of metabolites in infectious mice was improved by DADS, with increases in secondary bile acids, arachidonic acid, indoles and their derivatives, which were highly related to the multiple differentially altered metabolic pathways, namely, bile secretion, arachidonic acid metabolism, and tryptophan metabolism. This study indicated that DADS could modulate gut microbiota and metabolites and protect the gut barrier to alleviate DSS-induced intestinal C. albicans infection in mice. Moreover, this work might also provide novel insight into the treatment of C. albicans infection using DADS., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hu, Huang, Zhou, Yin and Tang.)

Lipopolysaccharide (LPS)-driven activation of Kupffer cells plays critical roles in the development of alcoholic liver disease (ALD). Accumulating evidence has revealed that nuclear factor erythroid 2-related factor 2 (Nrf2) can modulate the polarization of macrophages. The current study aimed to investigate the roles of diallyl disulfide (DADS) in LPS-driven inflammation in vitro and in vivo. We found that DADS significantly increased the nuclear translocation of Nrf2 and the transcription of Nrf2 targets, including HO1, NQO1, and γ-GCSc, and suppressed degradation of Nrf2 protein. Besides, DADS significantly inhibited LPS-induced activation of NF-κB and MAPK, secretion of NO and TNF-α, and production of reactive oxygen species (ROS) in LPS-exposed RAW264.7 cells. In vivo study demonstrated that DADS significantly ameliorated liver damage in mice challenged with LPS, as shown by the inhibition of increases in serum aminotransferase activities, neutrophil infiltration, and NF-κB and NLRP3 inflammasome activation. Finally, knockout of Nrf2 abrogated the suppression of DADS on macrophage polarization and on liver injury induced by LPS. These findings reveal that DADS suppresses LPS-driven inflammatory response in the liver by activating Nrf2, which suggests that the protective effects of DADS against ALD may be attributed to the modulation of Kupffer cell polarization in the liver., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Allicin compositions in garlic are used widely as fungicides in modern agriculture, in which diallyl disulfide (DADS) is a major compound. Downy mildew, caused by Pseudoperonospora cubensis ( P. cubensis ), is one of the most destructive diseases and causes severe yield losses in cucumbers. To explore the potential mechanism of DADS-induced cucumber resistance to downy mildew, cucumber seedlings were treated with DADS and then inoculated with P. cubensis at a 10-day interval. Symptom observation showed that DADS significantly induced cucumber resistance to downy mildew. Furthermore, both lignin and H 2 O 2 were significantly increased by DADS treatment to responding P. cubensis infection. Simultaneously, the enzyme activities of peroxidase (POD) in DADS-treated seedlings were significantly promoted. Meanwhile, both the auxin (IAA) and salicylic acid (SA) contents were increased, and their related differentially expressed genes (DEGs) were up-regulated when treated with DADS. Transcriptome profiling showed that many DEGs were involved in the biological processes of defense responses, in which DEGs on the pathways of 'phenylpropanoid biosynthesis', 'phenylalanine metabolism', 'MAPK signaling', and 'plant hormone signal transduction' were significantly up-regulated in DADS-treated cucumbers uninoculated with the pathogen. Based on the results of several physiological indices and transcriptomes, a potential molecular mechanism of DADS-induced cucumber resistance to downy mildew was proposed and discussed. The results of this study might give new insight into the exploration of the induced resistance mechanism of cucumber to downy mildew and provide useful information for the subsequent mining of resistance genes in cucumber.

In isoprenaline (ISO)-induced myocardial infarcted rats, garlic oil (GO) and its main ingredient, diallyl disulfide (DADS), were examined for cardioprotective effects when used with carvedilol (CAR). GO, DADS and CAR were given to rats in their respective groups, either alone or together, with the addition of isoprenaline (3 mg/kg/day, subcutaneously) during the last 10 days of treatment. At the end of 14 days of treatment, blood samples were collected, the hearts were excised under anesthesia and weighed. Heart tissue homogenate was used to measure superoxide dismutase (SOD), catalase (CAT), and thiobarbituric acid reactive substances (TBARS). Furthermore, the serum activities of cardiac markers, including lactate dehydrogenase, creatine kinase, and cardiac troponin, were checked. Moreover, inflammatory markers including tumor necrosis factor alpha, interleukin one beta, interleukin six, and kappa bp65 subunit were assessed. Rats that received GO, DADS, and CAR exhibited a significant increase in the cardiac antioxidant enzyme activities with a simultaneous decrease in serum cardiac markers enzymes and inflammatory markers. The TBARS were significantly reduced in rats that received treatment. The addition of carvedilol to GO or DADS significantly elevated antioxidant activities and decreased the release of cardiac enzymes into blood circulation. Both DADS and GOl were almost similar in efficacy, indicating the potential role of DADS in garlic oil-mediated cardioprotection. Combining GO or DADS with CAR increased CAR's cardioprotective impact and protected rats from developing ISO-induced myocardial infarction.

Neuroinflammation and oxidative stress play critical roles in pathogenesis of depression. Diallyl disulfide (DADS), an active compound in garlic oil, has been shown to exhibit obvious anti-inflammatory and anti-oxidative activities. Preliminary evidence indicates that depression is associated with high levels of pro-inflammatory cytokines and oxidative markers, suggesting that inhibition of neuroinflammatory response and oxidative stress may be beneficial for depression interruption. Here, we investigated the antidepressant effect of DADS as well as it mechanisms in a depression-like model induced by lipopolysaccharide (LPS). Similarly to imipramine (10 mg/kg), a clinical antidepressant, DADS (40 or 80 mg/kg), which was administered 1 h before LPS treatment (pre-LPS) or 1.5 h and 23.5 h after LPS treatment (post-LPS), prevented and reversed LPS (100 μg/kg)-induced increase in immobility time in the tail suspension test (TST) and forced swim test (FST) in mice. Mechanistic studies revealed that DADS pre-treatment or post-treatment at the dose of 40 and 80 mg/kg prevented and reversed (i) LPS-induced increases in interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and nitric oxide (NO) levels in the hippocampus and prefrontal cortex, (ii) LPS-induced increases in contents of malondialdehyde (MDA), a parameter reflecting high levels of oxidative stress, and (iii) LPS-induced decreases in contents of GSH, a marker reflecting weakened anti-oxidative ability, in the hippocampus and prefrontal cortex in mice. These results indicate that DADS is comparable to imipramine in effectively ameliorating LPS-induced depression-like behaviors in mice, providing a potential value for DADS in prevention and/or therapy of depression., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature.)

Diallyl disulfide (DADS), an oil-soluble sulfur compound that is responsible for the biological effects of garlic, displays numerous biological activities, among which its anti-cancer activities are the most famous ones. In recent years, the pharmacological effects of DADS other than its anti-carcinogenic activities have attracted numerous attentions. For example, it has been reported that DADS can prevent the microglia-mediated neuroinflammatory response and depression-like behaviors in mice. In the cardiovascular system, DADS administration was found to ameliorate the isoproterenol- or streptozotocin-induced cardiac dysfunction via the activation of the nuclear factor E2-related factor 2 (Nrf2) and insulin-like growth factor (IGF)-phosphatidylinositol-3-kinase (PI3K)-protein kinase B (Akt) signaling. DADS administration can also produce neuroprotective effects in animal models of Alzheimer's disease and protect the heart, endothelium, liver, lung, and kidney against cellular or tissue damages induced by various toxic factors, such as the oxidized-low density lipoprotein (ox-LDL), carbon tetrachloride (CCl 4 ), ethanol, acetaminophen, Cis-Diammine Dichloroplatinum (CisPt), and gentamicin. The major mechanisms of action of DADS in disease prevention and/or treatment include inhibition of inflammation, oxidative stress, and cellular apoptosis. Mechanisms, including the activation of Akt, extracellular signal-regulated kinase 1/2 (ERK1/2), protein kinase A (PKA), and cyclic adenosine monophosphate-response element binding protein (CREB) and the inhibition of histone deacetylases (HDACs), can also mediate the cellular protective effects of DADS in different tissues and organs. In this review, we summarize and discuss the pharmacological effects of DADS other than its anti-carcinogenic activities, aiming to reveal more possibilities for DADS in disease prevention and/or treatment., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background and Aim: Diallyl disulfide (DADS), a volatile sulfide extracted from garlic, has been suggested as a chemical of anti-atherosclerotic drugs, while its molecular mechanism for this benefit has not fully been understood. The aim of the present study was to investigate the effects of DADS on lipid metabolism and its potential mechanisms in HepG2 cells induced by lipopolysaccharides (LPS)., Methods and Results: HepG2 cells were treated with LPS with or without different concentrations of DADS (0, 20, 40, 80, 160 μg/ml) for 24 h. The cell activity was detected by CCK8, and Dil-LDL uptake assay was used to examine the LDL uptake. Real-time PCR and Western blot were used to detect the expression of LDLR, PCSK9 SREBP2 and HMGCR. In addition, we examined the effect of the combination of DADS with atorvastatin on PCSK9 expression. The results showed that LPS significantly increased PCSK9 and SREBP2 expressions in a dose-dependent manner in HepG2 cells. DADS attenuated PCSK9, SREBP2 and HMGCR expressions and up-regulated the expression of LDLR. Moreover, DADS reversed the expressions of PCSK9, SREBP2, HMGCR and LDLR induced by LPS and DADS could promote the LDL uptake in HepG2 cells. Furthermore, DADS decreased the expression of PCSK9 by activating the PI3K/Akt-SREBP2 signal pathway. Notably, DADS could reduce PCSK9 expression induced by atorvastatin in HepG2 cells., Conclusion: DADS could significantly attenuated PCSK9 expression in a dose-dependent manner induced by LPS and increased the LDLR expression in HepG2 cells, which was associated with the activation of PI3K/Akt-SREBP2 signaling pathway., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Continuous cropping obstacles seriously affect the sustainable production of tomatoes ( Solanum lycopersicum L.). Researchers have found that intercropping with garlic ( Allium sativum L.) could alleviate tomato continuous cropping obstacles. Diallyl disulfide (DADS) is the main allelochemical in garlic. However, the mechanism of DADS in alleviating tomato continuous cropping obstacles is still unknown. In this research, aqueous extracts of tomato continuous cropping soil were used to simulate the continuous cropping condition of tomato. Our results showed that DADS increased root activity and chlorophyll content and improved the activity of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD), and phenylalanine ammonia-lyase (PAL)) and the metabolism of nonenzymatic antioxidants (glutathione (GSH) and oxidized glutathione (GSSG)) in tomato plants. DADS treatment reduced the content of fatty acid esters in tomato root exudates (e.g., palmitate methyl ester, palmitoleic acid methyl ester, oleic acid methyl ester) and increased the level of substances such as dibutyl phthalate and 2,2'-methylenebis(6- tert -butyl-4-methylphenol). The higher concentrations of palmitate methyl ester inhibited tomato hypocotyl growth, while oleic acid methyl ester inhibited tomato root growth. Moreover, the application of DADS significantly inhibited the secretion of these esters in the root exudates. Therefore, it suggests that DADS may increase tomato resistance and promote tomato plant growth by increasing root activity and photosynthetic capacity and development to reduce autotoxicity of tomato.

Microglia are the innate immune cells in the nervous system. In the resting state, they display a ramified morphology, while upon disease stimulation their processes would be retracted, along with pro-inflammatory cytokine overproduction. Reversing microglial process retraction may help reduce pro-inflammatory cytokine production and restore microglia's ability to scan surrounding environments, rendering brain function regulation to be more effective. We found that diallyl disulfide (DADS), a major organosulfur compound in garlic oil, administered at different doses and time points, promoted microglial process elongation in both cultured systems and prefrontal cortexes in mice in a reversible manner. Lipopolysaccharide (LPS), a classical activator of microglia, did not affect this pro-elongation effect of DADS at conditions in vitro and in vivo. Functional studies revealed that DADS pre-treatment attenuated LPS-induced decreases in levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) mRNA as well as LPS-induced increases in levels of IL-10 and CD206 mRNA in both cultured microglia and prefrontal cortexes in mice. Protein kinase B (Akt) inhibition attenuated the pro-elongation effect of DADS on microglial process and blocked the regulatory effects of DADS on LPS-induced inflammatory responses in both cultured microglia and prefrontal cortexes in mice. In an in vivo model of neuroinflammation, DADS pre-treatment prevented LPS-induced retraction of microglial process in the prefrontal cortex in mice and attenuated LPS-induced increase in immobility time in the tail suspension test and forced swim test. These results indicate that DADS induces an Akt-dependent elongation of microglia process, along with the induction of an anti-inflammatory phenotype., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Cofilin is associated with cell differentiation; however, to the best of our knowledge, no data have indicated an association between the cofilin 1 pathway and leukemia cell differentiation. The present study investigated the involvement of the cofilin 1 signaling pathway in diallyl disulfide (DADS)‑induced differentiation and the inhibitory effects on the proliferation, migration, and invasion of human leukemia HL‑60 cells. First, it was identified that 8 µM DADS suppressed cell proliferation, migration and invasion, and induced differentiation based on the reduced nitroblue tetrazolium ability and increased CD11b and CD33 expression. DADS significantly downregulated the expression of cofilin 1 and phosphorylated cofilin 1 in HL‑60 leukemia cells. Second, it was verified that silencing cofilin 1 markedly promoted 8 µM DADS‑induced differentiation and the inhibitory effect on cell proliferation and invasion. Overexpression of cofilin 1 obviously suppressed 8 µM DADS‑induced differentiation and the inhibitory effect on cell proliferation and invasion. Third, the present study examined the mechanisms by which 8 µM DADS decreases cofilin 1 expression and activation. The results revealed that 8 µM DADS inhibited the mRNA and protein expression of Rac1, Rho‑associated protein kinase 1 (ROCK1) and LIM domain kinase 1 (LIMK1) as well as the phosphorylation of LIMK1 in HL‑60 cells, while 8 µM DADS enhanced the effects of the Rac1‑ROCK1‑LIMK1 pathway in cells overexpressing cofilin 1 compared with that in control HL‑60 cells. These results suggest that the anticancer function of DADS on HL‑60 leukemia cells is regulated by the Rac1‑ROCK1‑LIMK1‑cofilin 1 pathway, indicating that DADS could be a promising anti‑leukemia therapeutic compound.

Garlic (Allium sativum) - derived organosulfur compound diallyl disulfide (DADS) possesses antioxidant, anti-inflammatory and anti-cancer effects. This study was aimed to investigate the anti-inflammatory role and the underlying molecular mechanisms of DADS in cerulein-induced acute pancreatitis (AP) and associated lung injury. Administration of DADS significantly attenuated the severity of pancreatic and pulmonary inflammation by inhibiting cerulein induced serum amylase, myeloperoxidase activity (MPO) and histological changes in pancreas and lung. Furthermore, the anti-inflammatory effect of DADS was associated with the decrease in tumor necrosis factor (TNF)-α,cystathionine-γ-lyase (CSE), preprotachykinin A (PPTA), neurokinin-1-receptor (NK1R) expression and hydrogen sulfide (H 2 S) production in both pancreas and lung. In addition, DADS reduced caerulein-induced I-κB degradation and subsequent translocation of NF-κB in the pancreas and lung. These results show for the first time that in AP, DADS exhibits an anti-inflammatory effect by inhibiting CSE/H 2 S and SP/NK1R signaling and NF-кB pathway., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This study explored the chemical compositions of garlic essential oil, the inhibitory activity of garlic essential oil and diallyl disulfide (DADS) against Phytophthora nicotianae , and the effects on mycelial plasma membrane permeability and P. nicotianae inhibition. In total, 29 compounds were detected in garlic essential oil, of which 26 were detected by gas chromatography‒mass spectrometry (GC-MS) and 21 by headspace solid-phase microextraction (HS-SPME) GC-MS. DADS (60.12% and 19.09%) and trisulfide di-2-propenyl (14.18% and 17.98%) were the major components identified by HS-SPME GC-MS and GC-MS analysis, respectively. Half-inhibitory concentration (Ec50, antagonism) and minimum inhibitory concentration (MIC, fumigation) of DADS against P. nicotianae were 150.83 μL/L and 20 μL/L, respectively, while Ec50 of garlic essential oil was 1108.25 μL/L. Mycelial membrane permeability gradually increased in a concentration-dependent manner, and cell death increased at 450 μL/L DADS. Furthermore, DADS treatment significantly reduced the incidence of tobacco black shank and the number of P. nicotianae pathogens in rhizosphere soil. DADS also promoted root development of tobacco seedlings at low concentrations, which was inhibited at high concentrations. Therefore, DADS may play an important role in the antifungal effect against P. nicotianae by destroying mycelial cell membrane integrity, causing an increase in cell membrane permeability, and leading to cell death.

Combining natural products with chemotherapy and/or radiotherapy may increase the efficacy of cancer treatment. It has been hypothesized that natural products may inhibit DNA repair and sensitize cancer cells to DNA damage-based cancer therapy. However, the molecular mechanisms underlying these activities remain unclear. In this study, we found that diallyl disulfide (DADS), an organosulfur compound, increased the sensitivity of yeast cells to DNA damage and has potential for development as an adjuvant drug for DNA damage-based cancer therapy. We induced HO endonuclease to generate a specific DNA double-strand break (DSB) by adding galactose to yeast and used this system to study how DADS affects DNA repair. In this study, we found that DADS inhibited DNA repair in single-strand annealing (SSA) system and sensitized SSA cells to a single DSB. DADS impaired DNA repair by inhibiting the protein levels of the DNA resection-related proteins Sae2 and Exo1. We also found that the recruitment of MRX and the Mec1-Ddc2 complex to a DSB was prevented by DADS. This result suggests that DADS counteracts G2/M DNA damage checkpoint activation in a Mec1 (ATR)- and Tel1 (ATM)-dependent manner. Only by elucidating the molecular mechanisms by which DADS influences DNA repair will we be able to discover new adjuvant drugs to improve chemotherapy and/or radiotherapy., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this report, liver cells were treated with cadmium chloride (CdCl 2 ) and diallyl disulfide (DADS), a major compound from garlic to attenuate the toxic effect of Cd on transcriptome. The viability of Cd treated cells was reduced to 19.9% ± 2.4% in comparison to the untreated cells, whereas the viability of DADS pretreated cells was increased to 48.6% ± 2%. The attenuation effect of DADS was studied at shorter period (6 hours). Transcriptome analysis of CdCl 2 alone treated cells resulted in 2119 and 982 (up and down) regulated genes (≥ 2 or ≤ 2-fold), whereas pretreated cells with DADS resulted in 2597 and 1784 genes. These genes were known to function in many important biological processes. Affymetrix array analysis was validated by the pathway specific PCR array that exhibited the same trend of expression. The current study clearly shows the DADS attenuation effect on transcriptome in CdCl 2 -treated rat liver cells., (© 2019 Wiley Periodicals, Inc.)

Diallyl disulfide (DADs), a natural organic compound, is extracted from garlic and scallion and has anti-tumor effects against various tumors. This study investigated the anti-tumor activity of DADs in human osteosarcoma cells and the mechanisms. MG-63 cells were exposed to DADs (0, 20, 40, 60, 80, and 100 μM) for different lengths of time (24, 48, and 72 h). The CCK8 assay results showed that DADs inhibited osteosarcoma cell viability in a dose-and time-dependent manner. FITC-Annexin V/propidium iodide staining and flow cytometry demonstrated that the apoptotic ratio increased and the cell cycle was arrested at the G 2 /M phase as the DADs concentration was increased. A Western blot analysis was employed to detect the levels of caspase-3, Bax, Bcl-2, LC3-II/LC3-I, and p62 as well as suppression of the mTOR pathway. High expression of LC3-II protein revealed that DADs induced formation of autophagosome. Furthermore, DADs-induced apoptosis was weakened after adding 3-methyladenine, demonstrating that the DADs treatment resulted in autophagy-mediated death of MG-63 cells. In addition, DADs depressed p-mTOR kinase activity, and the inhibited PI3K/Akt/mTOR pathway increased DADs-induced apoptosis and autophagy. In conclusion, our results reveal that DADs induced G 2 /M arrest, apoptosis, and autophagic death of human osteosarcoma cells by inhibiting the PI3K/Akt/mTOR signaling pathway.

Obesity is a major problem in developed countries and a burden on social health care systems. Several epidemiological studies showed the protective effects of green tea against obesity-related diseases. Cyclic guanosine monophosphate (cGMP) acts as a mediator for the physiological effects of (-)-epigallocatechin-3-O-gallate, the major constituent of green tea. Here, we showed that the level of phosphodiesterase 5, a negative regulator of cGMP, was up-regulated in adipose tissues of high-fat/high-sucrose (HF/HS) diet-fed mice and that this up-regulation was ameliorated by diallyl disulfide (DADS), the major organosulfur in garlic. A green tea extract (GT) and DADS in combination attenuated HF/HS diet-induced adipose increase and triglyceride accumulation in the liver. In these mechanisms, the combination regimen suppressed the HF/HS diet-induced up-regulation of fatty acid synthesis-related enzymes including sterol regulatory element-binding protein-1 (SREBP-1), fatty acid synthase, and stearoyl-CoA desaturase-1. Moreover, this combination diet up-regulated thermogenesis-related genes including peroxisome proliferator-activated receptor (PPAR) gamma coactivator 1 alpha and uncoupling proteins in both white and brown adipose tissues. In conclusion, we identified DADS as an enhancer of the anti-obesity effect of GT accompanied by the suppression of SREBP-1 and activation of PPAR axis. The combination diet is a novel and easily applicable approach against obesity-related diseases., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Cancer is a multi-factorial disease including alterations in the cell signalling pathways. Currently, several drugs are in use to treat cancer but such drugs show negative side effects on normal cells and cause severe toxicity., Methods: The current research is mainly focused on medicinal plants with potential therapeutic efficacy in the treatment of cancer without any adverse effects on normal cells. In this regard, garlic and its active compounds including diallyl sulfide, diallyl trisulfide, ajoene, and allicin have been established to suppress the growth of cancer and killing of cancer cells., Result: The review focuses on garlic and its active compounds chemopreventive effect through modulating various cell signalling pathways. Additionally, garlic and its active compound were established to induce cell cycle arrest at the G0/G1 phase and G2/M phases in cancer cells, increase the expression of tumor suppressor genes, inhibit the angiogenesis process, induction of apoptosis and modulation of various other genetic pathways., Conclusion: This review sketches the diverse chemopreventive activities of garlic and their active ingredients in the management of cancer mainly focusing on cell signalling pathways., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The purposes of this study were to probe spectral behaviors of the toxic targets in trans-crotonaldehyde (TCA) in mitochondria altered by diallyl disulfides (DADS) derived from garlic. Ultraviolet absorption spectra showed that when ethanol as a solvent, the DADS blue shifted the peak of TCA from 318 nm to 312 nm. In mitochondria, the DADS further blue displaced the peak of TCA from 312 nm to 308 nm. Raman spectra displayed that the SS of DADS directly interacted with the CC toxic target of TCA, then the CCC of DADS interacted with the CHO toxic target of TCA. When DADS to TCA was 1:2, the DADS was the most powerful for the removal of the CC and CHO toxic targets of TCA. Study suggested that the SS of DADS altered the CC toxic target of TCA, while the CCC of DADS eliminated the CHO toxic target of TCA via local electron delocalization. The above two together clearly depicted the spectral behaviors of the toxic targets of TCA in mitochondria altered by DADS. These results are of great significance and value to elucidate the effects of garlic organic polysulfide on myocardial ischemia for the extensive development and use of garlic extracts., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Garlic ( Allium sativum ) has traditionally been used as a medicinal food and exhibits various beneficial activities, such as antitumor, antimicrobial, hypolipidemic, antiarthritic, and hypoglycemic activities. The aim of this study was to explore the preventive effect of garlic oil (GO) and its organosulfur component diallyl disulfide (DADS) on cigarette smoke (CS)-induced airway inflammation. Mice were exposed to CS daily for 1 h (equivalent to eight cigarettes per day) for two weeks, and intranasally instilled with lipopolysaccharide (LPS) on day 12 after the initiation of CS exposure. GO and DADS were administered to mice by oral gavage, both at rates of 20 and 40 mg/kg, for 1 h before CS exposure for two weeks. In the bronchoalveolar lavage fluid, GO and DADS inhibited the elevation in the counts of inflammatory cells, particularly neutrophils, which were induced in the CS and LPS (CS + LPS) group. This was accompanied by the lowered production (relative to the CS + LPS group) of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. Histologically, GO and DADS inhibited the CS- and LPS-induced infiltration of inflammatory cells into lung tissues. Additionally, GO and DADS inhibited the phosphorylation of extracellular signal-regulated kinase and the expression of matrix metalloproteinase-9 in the lung tissues. Taken together, these findings indicate that GO and DADS could be a potential preventive agent in CS-induced airway inflammation.

Most allelochemicals are phytotoxic to the receiver plants and may influence the cell micro- and ultrastructure, cell division, phytohormone levels, and ultimately growth. In order to understand the allelopathic potential of garlic, the effects of its main bioactive allelochemical diallyl disulfide (DADS), experiments were carried out to observe the seed germination, root growth, and developmental responses in cucumber seedlings treated with various concentrations of DADS. The obtained data suggested active influence of DADS on cucumber root growth and development. Significant responses were observed in early root growth and elongation, mitotic cell division and elongation, and root architecture modulation. The effect, however, was dose dependent, and lower concentrations of DADS proved to be promotional whereas higher concentrations of DADS inhibited cucumber root growth and development. Relative root elongation (RRE) revealed that DADS could increase growth of cucumber roots in the early developmental days. Moreover, DADS application significantly influenced mitosis-related gene expression. Observed genes CYCA and CDKB were initially downregulated in the first 24 h but significantly upregulated after 48 h, while gene CDKA was upregulated in the first 24 h. Similarly, DADS application significantly altered primary plant hormones, such as IAA, ABA, GA 3 , and ZR, in the cucumber roots. Taken together, low concentrations of DADS treatment could promote cucumber root growth and induce main root elongation by upregulating CDKA and CDKB gene expression and regulating hormone balance in root. The current findings offer insight into the allelopathic potential of garlic allelochemical DADS and can be considered vital for establishing plant allelopathic studies., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Objective: This study investigated effects of S-allylmercaptocysteine (SAMC), diallyl disulfide (DADS), and vitamin B 12 on inner ear functions and morphology after long-period high-level broadband noise exposure., Materials and Methods: Twenty-four healthy rats were randomly divided into four groups. First group was chosen as the control group. Vitamin B 12 , SAMC, and DADS were applied to other groups for 4 weeks. On the 14th day, each group was exposed to broadband noise. Auditory brainstem response test was performed before and immediately after noise exposure and repeated on the 2nd and 14th day., Results: Permanent threshold shifts were significantly lower in groups treated with vitamin B 12 , SAMC, and DADS. Histologically, cochleae of SAMC and DADS groups were found to be better preserved than the cochleae of vitamin B 12 and control groups., Conclusion: Physiologically and histologically, SAMC and DADS reduced the long-term effects of noise. However, physiological recovery was not consistent with the morphological findings in vitamin B 12 group., Competing Interests: None

Garlic oil can disrupt the quorum sensing (QS) pathways of the opportunistic pathogen Pseudomonas aeruginosa; however, the underlying mechanisms for this effect are unclear. Diallyl disulfide (DADS) is one of the most abundant sulfur-containing compounds in garlic oil. This study investigated the effects of DADS on the growth, virulence factor production (elastase, pyocyanin, biofilm, and swarming motility), and essential gene expression of P. aeruginosa PAO1, particularly as they apply to QS and virulence. DADS at 1.28 mg/mL did not affect P. aeruginosa PAO1 growth, although it decreased elastase and pyocyanin production, biofilm formation, and swarming motility. Each of these phenomena is regulated by the three QS systems of P. aeruginosa PAO1 (las, rhl, and pqs). Real-time q-PCR revealed that DADS down-regulated the transcription levels of several important QS genes (lasI, lasR, rhlI, rhlR, pqsA, and pqsR) in the three systems. Furthermore, the transcription levels of QS-regulated virulence genes were also down-regulated. The lasB gene, encoding LasB elastase, is co-regulated by the las, rhl, and pqs systems, and thus the down-regulation of genes across the three systems further down-regulated lasB. Additionally, phzM (encoding pyocyanin), pslB (responsible for the production of a biofilm matrix polysaccharide), and chiC (encoding chitinase) were positively activated by LasR, and a decrease in lasR transcription further down-regulated the transcription of phzM, pslB, and chiC. Hence, DADS inhibits P. aeruginosa PAO1 virulence factors by inactivating the transcription of key genes across three different QS systems.

Strategies based on mesenchymal stem cell (MSC) therapy for restoring injured articular cartilage are not effective enough in osteoarthritis (OA). Due to the enhanced inflammation and oxidative stress in OA microenvironment, differentiation of MSCs into chondrocytes would be impaired. This study aims to explore the effects of diallyl disulfide (DADS) on IL-1β-mediated inflammation and oxidative stress in human adipose derived mesenchymal stem cells (hADSCs) during chondrogenesis. MTT assay was employed to examine the effects of various concentrations of DADS on the viability of hADSCs at different time scales to obtain non-cytotoxic concentration range of DADS. The effects of DADS on IL-1β-induced intracellular ROS generation and lipid peroxidation were evaluated in hADSCs. Western blotting was used to analyze the protein expression levels of IκBα (np), IκBα (p), NF-κB (np) and NF-κB (p). Furthermore, the gene expression levels of antioxidant enzymes in hADSCs and chondrogenic markers at days 7, 14 and 21 of differentiation were measured using qRT-PCR. The results showed that addition of DADS significantly enhanced the mRNA expression levels of antioxidant enzymes as well as reduced ROS elevation, lipid peroxidation, IκBα activation and NF-κB nuclear translocation in hADSCs treated with IL-1β. In addition, DADS could significantly increase the expression levels of IL-1β-induced impaired chondrogenic marker genes in differentiated hADSCs. Treatment with DADS may provide an effective approach to prevent the pro-inflammatory cytokines and oxidative stress as catabolic causes of chondrocyte cell death and enhance the protective anabolic effects by promoting chondrogenesis associated gene expressions in hADSCs exposed to OA condition.

In the present study, we have demonstrated receptor for advanced glycation endproducts (RAGE) as a target for delivery of drugs specifically to triple negative breast cancer cells. We have prepared solid lipid nanoparticle formulation of cytotoxic agent di-allyl-disulfide (DADS) to overcome its bioavailability issues. Then, we have surface modified DADS-loaded solid lipid nanoparticles (DADS-SLN) with RAGE antibody to achieve site-specific delivery of DADS to TNBC cells. We found a significant cellular internalization of RAGE surface modified DADS-SLN (DADS-RAGE-SLN) when compared to DADS-SLN. The cytotoxic effect of DADS was also significantly improved with DADS-RAGE-SLN by downregulating anti-apoptotic proteins and upregulating pro-apoptotic proteins as observed by western blot analysis. RAGE-targeted delivery of cytotoxic agents can be, therefore, a promising approach for improving antitumour activity and reducing off-target effects.

Diallyl disulfide (DADS) is the main organosulfur ingredient in garlic, with known antioxidant and anti-inflammatory activities. The aim of the present study was to investigate the effect of DADS on reducing the inflammation and redox imbalance in a rat emphysema model that was induced by intraperitoneal injection of cigarette smoke extract (CSE). Briefly, DADS exerted an anti-inflammation effect on emphysema rats through decreasing cell influx in the bronchoalveolar lavage fluid (BALF) and suppressing pro-inflammation cytokine production including tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) via inhibiting the NF-κB pathway. In addition, levels of oxidative stress markers including malondialdehyde (MDA) and myeloperoxidase (MPO) were reduced, while the activities of glutathione (GSH), glutathione peroxidase (GSH-PX), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) were markedly enhanced by DADS. Moreover, MMP-9 and TIMP-1 expression were down-regulated by DADS. Furthermore, the regulation effects of DADS on CD4⁺ and CD8⁺ T cells were observed. In conclusion, these encouraging findings suggest that DADS could be considered as a promising anti-inflammation and antioxidative agent for the treatment of emphysema., Competing Interests: The authors declare no conflict of interest.

Background: It has been reported that diallyl disulfide (DADS) has anti-proliferative activity in many cancers., Objective: The purpose of this study was to investigate the functions of DADS and the underlying mechanisms of its effect in breast cancer stem cells (BCSCs)., Method: Mammosphere formation assay, glucose consumption assay, lactate production assay and mouse xenograft experiments were performed to explore the functions of DADS in BCSCs. ATPase activity assay, western blotting and immunohistochemistry (IHC) assay were conduct to explore the mechanisms underlying the effects of DADS in BCSCs., Results: The results showed that DADS suppressed cell stemness and glucose metabolism in BCSCs. In vivo mouse xenograft experiments showed that DADS inhibited the proliferation and metastasis of BCSCs. Then, we continued to explore the mechanisms underlying the effects of DADS in BCSCs and found that DADS acts by targeting CD44, Pyruvate kinase M2 (PKM2) and AMP-activated protein kinase (AMPK) signaling pathways. IHC analysis of 125 breast cancer patients' tissues demonstrated that CD44, PKM2 and AMPK expression levels were positively correlated. In addition, positive CD44, PKM2 and AMPK expression was associated with poor patient overall survival (OS) and disease-free survival (DFS)., Conclusion: In summary, DADS suppresses cell stemness, proliferation, metastasis and glucose metabolism in BCSCs partly through the inhibition of CD44/PKM2/AMPK. DADS may be used as a potential therapy for breast cancer treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Lipoprotein(a) [LP(a)] is implicated as a common and independent risk factor for cardiovascular diseases. The therapeutic options currently available for reducing plasma LP(a) concentrations are limited. Diallyl disulphide (DADS), the main component of garlic, regulates lipid metabolism in hepatocytes and adipocytes through ERK1/2 signalling. This study aimed to assess the effect of DADS on apolipoprotein(a) [apo(a)] in HepG2 cells. We also determined the effects of DADS on apo(a) expression and secretion in HepG2 cells as well as the underlying mechanisms., Methods: We examined the role of DADS on apo(a) expression in HepG2 cells by treating cell with different concentrations of DADS (10, 20, 40 and 80 μg/mL) for 24 h or treating cells with 40 μg/mL DADS for 0, 6, 12, 24 and 48 h. Then we used quantitative real-time PCR to analysis apo(a) mRNA levels, used Western blot to analysis apo(a) protein levels and used enzyme-linked immunosorbent assay to test apo(a) secreted levels. To farther determined the role of DADS, we applied Transfection of small interfering RNA to knockdown ELK-1levels and applied PD98059, a specific inhibitor of ERK1/2, to block ERK1/2 signal., Results: The results show DADS inhibited apo(a) at both the mRNA and protein levels in HepG2 cells in a dose-dependent manner. DADS-mediated inhibition of apoa(a) expression in HepG2 cells was attenuated when the cells were cultured in medium containing PD98059 (ERK1/2 inhibitor) or were transfected with siRNAs against MEK1 or ELK-1. Overexpression of apo(a) yielded similar results., Conclusions: This study reveals that DADS can downregulate apo(a) expression in a dose-dependent manner via the MEK-ERK12-ELK-1 pathway.

The aim of this study was to investigate the potential protective effects of diallyl disulfide (DADS) against acetaminophen (AAP)-induced acute hepatotoxicity and elucidate the molecular mechanisms underlying these protective effects in rats. Treatment with AAP caused acute hepatotoxicity manifested by elevated levels of aspartate aminotransferase and alanine aminotransferase with corresponding histopathological changes and high levels of oxidative stress in the livers. AAP treatment also caused hepatocellular apoptosis with phosphorylation of c-Jun-N-terminal protein kinase (JNK). In addition, AAP caused activation of nuclear factor kappaB (NF-κB) concurrent with induction of inflammatory mediators. In contrast, pretreatment with DADS effectively attenuated acute liver injury and oxidative stress caused by AAP. DADS pretreatment suppressed cytochrome P450 2E1 (CYP2E1) levels in a dose-dependent manner and inhibited elevation of CYP2E1 activity induced by AAP. DADS pretreatment suppressed the phosphorylation of JNK and attenuated hepatocellular apoptotic changes. In addition, DADS inhibited the nuclear translocation of NF-κB and subsequent induction of inflammatory mediators. Overall, these results indicate that DADS confers a protective effect against oxidative stress-mediated JNK activation and apoptotic changes caused by AAP in the rat livers. This may be due to its ability to inhibit CYP2E1, enhance antioxidant enzymes activities, and suppress NF-κB activation., (Copyright © 2017. Published by Elsevier Ltd.)

The protective effects and mechanisms of DADS on IL-1β-mediated oxidative stress and mitochondrial apoptosis were investigated in C28I2 human chondrocytes. The effect of various concentrations of DADS (1, 5 10, 25, 50, and 100 μM) on C28I2 cell viability was evaluated in different times (2, 4, 8, 16, and 24 h) to obtain the non-cytotoxic concentrations of drug by MTT-assay. The protective effect of non-toxic concentrations of DADS on experimentally induced oxidative stress and apoptosis by IL-1β in C28I2 was evaluated. The effects of DADS on IL-1β-induced intracellular ROS production and lipid peroxidation were detected and the proteins expression of Nrf2, Bax, Bcl-2, caspase-3, total and phosphorylated JNK, and P38 MAPKs were analyzed by Western blotting. The mRNA expression of detoxifying phase II/antioxidant enzymes including heme oxygenase-1, NAD(P)H quinine oxidoreductase, glutathione S-transferase-P1, catalase, superoxide dismutase-1, glutathione peroxidase-1, -3, -4 were evaluated by reverse transcription-polymerase chain reaction. DADS in 1, 5, 10, and 25 μM concentrations had no cytotoxic effect after 24 h. Pretreatment with DADS remarkably increased Nrf2 nuclear translocation as well as the genes expression of detoxifying phase II/antioxidant enzymes and reduced IL-1β-induced elevation of ROS, lipid peroxidation, Bax/Bcl-2 ratio, caspase-3 activation, and JNK and P38 phosphorylation. DADS could considerably reduce IL-1β-induced oxidative stress and consequent mitochondrial apoptosis, as the major mechanisms of chondrocyte cell death in an experimental model of osteoarthritis. It may be considered as natural product in protecting OA-induced cartilage damage in clinical setting. J. Cell. Biochem. 118: 1879-1888, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Barrett's esophagus (BE) is generally accepted as the only precursor to esophageal adenocarcinoma (EAC). Deoxycholic acid (DCA)-induced inflammation and apoptotic resistance play an important role in the carcinogenesis and progression from BE to EAC. Diallyl disulfide (DADS) is a garlic-derived natural organosulfur compound. This study investigated whether DADS has chemopreventive effects against BE and the potentially related signaling pathway. BAR-T cells were treated with DCA in the presence or absence of DADS. An MTT assay was used to detect the viability of the cells. The apoptosis rate of the cells was measured by light microscopy and flow cytometry. ROS levels were determined by fluorescence microscopy and flow cytometry. Real-time PCR and ELISA were used to detect mRNA and protein levels, respectively. The levels of target proteins were also determined by western blot analysis. DADS did not inhibit cell viability in a certain concentration range. DADS, similar to the NF-κB inhibitor PDTC, inhibited the DCA-induced ROS production, inflammatory factors, IκBα phosphorylation, and expression of p50 in the nucleus in a dose-dependent manner. DADS also increased the cell apoptosis rate through down-regulating the level of Bcl-2. DADS has low cytotoxicity in BAR-T cells. It has an anti-inflammatory effect in BAR-T cells through inhibiting ROS and the NF-κB signaling pathway. Further, it abolishes the apoptotic resistance induced by DCA in an NF-κB/Bcl-2 dependent manner. DADS may be a good candidate for BE and EAC chemical prevention and therapy.

The current work was carried out by the principles of quality-by-design approach to develop an optimized solid lipid nanoparticles (SLNs) formulation of diallyl disulfide (DADS) through systematic statistical study. And its antitumor activity of DADS was also evaluated on breast cancer cell lines. To understand the effect of formulation variables (critical parameters) on the responses (critical quality attributes) of SLN, a 3-factor, 3-level Box-Behnken design, was explored to predict the responses such as particle size (Y1) and % entrapment efficiency (EE) (Y2) when concentration of surfactant (X1), amount of lipid (X2), and volume of solvent (X3) were selected as independent variables. Particle size analysis revealed that all the batches were within the nanometer range. DADS was released from the SLN much more rapidly at pH 4.5 than at pH 7.4, which is a desirable characteristic for tumor-targeted drug delivery. The cytotoxicity, reactive oxygen species (ROS), determination revealed that the antitumor activity of DADS is enhanced with SLN compared to DADS-free drug, and apoptosis is the mechanism underlying the cytotoxicity. The present study indicated the remarkable potential of DADS-SLN in enhancing the anticancer effect of DADS in breast cancer cells in vitro.

Diallyl disulfide (DADS) is a degradation product of allicin which is contained in garlic. This study investigated the protective effects of DADS against acetaminophen (AAP)-induced nephrotoxicity and the molecular mechanisms of nephroprotective effects in rats. AAP caused severe nephrotoxicity as evidenced by significant increases in renal tubular cell apoptosis, mitochondria-mediated apoptosis, and up-regulation of nuclear transcription factor kappa-B (NF-κB), cyclooxygenase-2 (Cox-2), and tumor necrosis factor-α (TNF-α) in the kidney with histopathological alterations. After AAP administration, glutathione content and activities of catalase, superoxide dismutase, and glutathione reductase were significantly decreased whereas malondialdehyde content was significantly increased, indicating that AAP-induced kidney injury was mediated through oxidative stress. In contrast, DADS pretreatment significantly attenuated AAP-induced nephrotoxic effects, including oxidative damage, histopathological lesions, and apoptotic changes in the kidney. DADS also attenuated AAP-induced up-regulation of NF-κB, Cox-2, and TNF-α in the kidney, and microsomal CYP2E1 expression in liver and kidney. These results indicated that DADS could prevent AAP-induced nephrotoxicity. The protective effects of DADS might be due to its ability to decrease metabolic activation of AAP by inhibiting CYP2E1 and its potent antioxidant, antiapoptotic, and antiinflammatory effects via inhibition of NF-κB., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Leukemia is a hematological malignancy which is produced by uncontrolled proliferation of leukocyte precursors. Currently, alternative medicines, using herb extracts, have been developed for cancer treatment. In this study, the effect of diallyl disulfide (DADS) on the induction of apoptosis and autophagy was investigated in K562 and NB4 myeloid leukemia cells. Leukemia cells were treated with various concentrations of DADS for 24 and 48 h. The percentage of cell viability was measured using an MTT assay. The percentages of apoptosis and autophagy were analyzed by staining with annexin-FITC and anti-LC3 FITC-conjugated antibodies, respectively. Then, the stained cells were detected by flow cytometry. In addition, PP242, a mammalian target rapamycin (mTOR) inhibitor, was used to study the involvement of the mTOR pathway in DADS-induced apoptosis and autophagy. mTOR mRNA expression was measured by real-time PCR. The results showed that DADS decreased cell viability and increased the percentage of cell apoptosis in a dose- and time-dependent manner. mTOR expression was significantly decreased in DADS- and mTOR inhibitor-treated cells. The highest percentages of apoptosis and autophagy were shown in cells treated with 100 μg/ml DADS combined with 10 μM of the mTOR inhibitor. According to our results, DADS could induce apoptosis and autophagy via the mTOR pathway in both K562 and NB4 myeloid leukemia cell lines.

The binding reaction of allicin and diallyl disulfide with β-lactoglobulin and the influence of pH value and protein denaturation on this reaction have been examined in the present study. Regardless of the structural similarity of both the organosulfur compounds, their binding behavior was significantly different. Both ligands were covalently bound by the free thiol group of the protein, whereas the affinity for allicin was significantly higher. In addition, diallyl disulfide was non-covalently bound. The binding reaction of both ligands was very sensitive to the pH value during incubation. The optimal pH range was between pH 8.0 and 9.0. Protein denaturation increased the reaction rate and reduced the number of binding sites for allicin, whereas the number of non-covalent binding sites increased for diallyl disulfide. Based on these findings, it can be proposed that the covalent modification of β-lactoglobulin functions as a specific transporter stabilizing allicin or diallyl disulfide., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The whey protein β-lactoglobulin has been proposed as a transporter for covalent bound bioactive compounds in order to enhance their stability and reduce their sensory perception. The garlic derived compounds allicin and diallyl disulfide were bound covalently to the native and heat denatured protein. The binding site and the influence of the modification on the digestibility were determined by mass spectrometric analysis of the modified β-lactoglobulin. Further, the conformation of the modified protein was assessed by circular dichroism and dynamic light scattering. The free thiol group of Cys(121) turned out to be the major binding site. After proteolysis with trypsin at pH 7 but not with pepsin at pH 2, a limited transfer to other cysteinyl residues was observed. The covalently bound ligands did not mask any proteolytic cleavage sites of pepsin, trypsin or chymotrypsin. The modified β-lactoglobulin showed a native like conformation, besides a moderate loosening of protein folding. The covalent binding of organosulfur compounds to β-lactoglobulin provides a bioactive ingredient without impairing the digestibility and functional properties of the protein., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Diallyl disulfide (DADS) has been shown to have multi-targeted antitumor activities. We have previously discovered that it has a repressive effect on LIM kinase-1 (LIMK1) expression in gastric cancer MGC803 cells. This suggests that DADS may inhibit epithelial-mesenchymal transition (EMT) by downregulating LIMK1, resulting in the inhibition of invasion and growth in gastric cancer. In this study, we reveal that LIMK1 expression is correlated with tumor differentiation, invasion depth, clinical stage, lymph node metastasis, and poor prognosis. DADS downregulated the Rac1-Pak1/Rock1-LIMK1 pathway in MGC803 cells, as shown by decreased p-LIMK1 and p-cofilin1 levels, and suppressed cell migration and invasion. Knockdown and overexpression experiments performed in vitro demonstrated that downregulating LIMK1 with DADS resulted in restrained EMT that was coupled with decreased matrix metalloproteinase-9 (MMP-9) and increased tissue inhibitor of metalloproteinase-3 (TIMP-3) expression. In in vitro and in vivo experiments, the DADS-induced suppression of cell proliferation was enhanced and antagonized by the knockdown and overexpression of LIMK1, respectively. Similar results were observed for DADS-induced changes in the expression of vimentin, CD34, Ki-67, and E-cadherin in xenografted tumors. These results indicate that downregulation of LIMK1 by DADS could explain the inhibition of EMT, invasion and proliferation in gastric cancer cells.

TNFα receptors are constitutively overexpressed in tumor cells, correlating to sustain elevated NFκB and monocyte chemotactic protein-1 (MCP-1/CCL2) expression. The elevation of CCL2 evokes aggressive forms of malignant tumors marked by tumor associated macrophage (TAM) recruitment, cell proliferation, invasion and angiogenesis. Previously, we have shown that the organo-sulfur compound diallyl disulfide (DADS) found in garlic (Allium sativum) attenuates TNFα induced CCL2 production in MDA-MB-231 cells. In the current study, we explored the signaling pathways responsible for DADS suppressive effect on TNFα mediated CCL2 release using PCR Arrays, RT-PCR and western blots. The data in this study show that TNFα initiates a rise in NFκB mRNA, which is not reversed by DADS. However, TNFα induced heightened expression of IKKε and phosphorylated ERK. The expression of these proteins corresponds to increased CCL2 release that can be attenuated by DADS. CCL2 induction by TNFα was also lessened by inhibitors of p38 (SB202190) and MEK (U0126) but not JNK (SP 600125), all of which were suppressed by DADS. In conclusion, the obtained results indicate that DADS down regulates TNFα invoked CCL2 production primarily through reduction of IKKε and phosphorylated-ERK, thereby impairing MAPK/ERK, and NFκB pathway signaling. Future research will be required to evaluate the effects of DADS on the function and expression of TNFα surface receptors., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Objective: Garlic (Allium sativum) has been considered a wonder herb for years with a reputation of disease prevention. Telomerase, a ribonucleoprotein enzyme responsible for telomere integrity, is strongly up-regulated in different types of cancers. The aim of this study was to reveal the role of diallyl disulfide (DADS), an organosulfur component of garlic, on telomerase activity in human lymphoma with an emphasis on key transcription factors c-Myc and Sp-1., Methods: Human lymphoma cell line U937 was used as model cell line. Telomerase activity was measured by telomerase repeat amplification protocol assay, levels of related proteins and mRNAs were measured by Western blot and reverse transcriptase polymerase chain reaction, respectively. Moreover, in vitro binding assay was performed using radiolabeled double-stranded DNA having specific sequences to detect involvement of transcription factors in DADS-dependent modulation of telomerase activity., Results: The present study demonstrated DADS-mediated decrease in telomerase activity in U937 cells with concomitant transcriptional down-regulation of human telomerase reverse transcriptase (hTERT) that is caused by reduced binding of c-Myc and Sp-1 to their respective binding sites on hTERT promoter. Lowering of DNA-binding activity of c-Myc and Sp-1 due to DADS treatment is caused by the deactivation of these transcription factors due to cleavage. Additionally, Mad1-the repressor protein of hTERT expression-is also overexpressed in DADS-treated U937 cells., Conclusions: These findings strongly suggest that DADS down-regulate telomerase activity through c-Myc-, Sp-1-, and Mad1-dependent transcriptional down-regulation of hTERT., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Scope: Although diallyl disulfide (DADS), an important garlic (Allium sativum) derivative, has exhibited potential anticancer activity, the molecular mechanism of this activity remains unknown. In this study, we evaluated the antitumor activity of DADS in triple-negative breast cancer (TNBC) cell lines based in vitro and in vivo models., Methods and Results: We found that treatment with DADS resulted in decreased viability, increased apoptosis, and suppression of metastatic potential in TNBC cells. Furthermore, DADS induced dysregulation of B-cell lymphoma (Bcl)-2 family members, downregulation of matrix metalloproteinase (MMP)-9 and reversal of the epithelial-mesenchymal transition (EMT). Interestingly, DADS significantly inhibited activation of the β-catenin signaling pathway, which regulated Bcl-2 family members, MMP-9 and EMT in TNBC cells. Consistent with these in vitro findings, we also verified the anticancer potential of DADS in MDA-MB-231 xenograft mice. Treatment with DADS significantly reduced tumor volume and weight and increased apoptosis in these mice, while the expression of active β-catenin was decreased, and the downstream molecules were dysregulated., Conclusion: Our results show that the antitumor effect of DADS on TNBC cells is mediated by the β-catenin pathway, suggesting that DADS could be used as a potential therapeutic agent for treating or preventing breast cancer., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This study was conducted to investigate the potential effects of diallyl disulfide (DADS) on carbon tetrachloride (CCl4 )-induced acute hepatotoxicity and to determine the molecular mechanisms of protection offered by DADS in rats. DADS was administered orally at 50 and 100 mg/kg/day once daily for 5 consecutive days prior to CCl4 administration. The single oral dose of CCl4 (2 mL/kg) caused a significant elevation in serum aspartate and alanine aminotransferase activities, which decreased upon pretreatment with DADS. Histopathological examinations showed extensive liver injury, characterized by extensive hepatocellular degeneration/necrosis, fatty changes, inflammatory cell infiltration, and congestion, which were reversed following pretreatment with DADS. The effects of DADS on cytochrome P450 2E1 (CYP2E1), the major isozyme involved in CCl4 bioactivation, were also investigated. DADS pretreatment resulted in a significant decrease in CYP2E1 protein levels in dose-dependent manner. In addition, CCl4 caused a decrease in protein level of cytoplasmic nuclear factor E2-related factor 2 (Nrf2) and suppression of nuclear translocation of Nrf2 concurrent with downregulation of detoxifying phase II enzymes and a decrease in antioxidant enzyme activities. In contrast, DADS prevented the depletion of cytoplasmic Nrf2 and enhanced nuclear translocation of Nrf2, which, in turn, upregulated antioxidant and/or phase II enzymes. These results indicate that the protective effects of DADS against CCl4 -induced hepatotoxicity possibly involve mechanisms related to its ability to induce antioxidant or detoxifying enzymes by activating Nrf2 and block metabolic activation of CCl4 by suppressing CYP2E1., (© 2013 Wiley Periodicals, Inc.)