Benzyl isothiocyanate exhibits anti-inflammatory effects in murine macrophages and in mouse skin

Salvadora persica leaves: phytochemical profile and in vitro-inhibitory activity on inflammatory mediators implicated in periodontal disease

CONTEXT

Virtually all parts of Salvadora persica L. (Salvadoraceae) are used in traditional medicine. The twigs and leaves are used for oral health, but leaves are far less investigated.

OBJECTIVE

This study assesses the oral health-promoting potential of S. persica leaves with emphasis on anti-inflammatory and antiproliferative effects and provides an in depth-characterization of their metabolite profile.

MATERIALS AND METHODS

Hot-water and methanolic S. persica leaf extracts (1, 10, and 100 µg/mL) and their major constituents (5, 10, and 50 µM), were subjected to cellular assays on IL-8 and TNFα release in LPS-stimulated human neutrophils, NO-release in LPS/IFNγ stimulated mouse macrophages, and proliferation of HNO97 human tongue carcinoma cells. Metabolite profiling was performed by UHPLC-HRMS analysis. Major constituents were isolated and structurally elucidated.

RESULTS AND DISCUSSION

Both extracts showed pronounced anti-inflammatory activity in LPS-stimulated neutrophils. Major identified compound classes were flavonoid glycosides, the glucosinolate glucotropaeolin, phenyl- and benzylglycoside sulfates, and megastigmane glycosylsulfates, the latter ones identified for the first time in S. persica. Glucotropaeolin strongly inhibited the release of IL-8 and TNF-α (13.3 ± 2.0 and 22.7 ± 2.6% of the release of stimulated control cells at 50 µM), while some flavonoids and 3-(3'-O-sulfo-β-d-glucopyranosyloxy)-7,8-dihydro-β-ionone, a newly isolated megastigmane glycosylsulfate, were moderately active. Benzylisothiocyanate, which is likely formed from glucotropaeolin during traditional application of S. persica, showed considerable antiproliferative activity (IC50 in HNO97 cells: 10.19 ± 0.72 µM) besides strongly inhibiting IL-8 and TNFα release.

CONCLUSIONS

Glucotropaeolin and benzylisothiocyanate are likely implicated in the oral health-promoting effects of S. persica leaves. The chemistry and pharmacology of the newly identified megastigmane glycosylsulfates should be further evaluated.

Nonswellable Hydrogel Patch with Tissue-Mimetic Mechanical Characteristics Remodeling In Vivo Microenvironment for Effective Adhesion Prevention

Postoperative adhesion is a common complication after abdominal surgery, but current clinical products have unsatisfactory therapeutic effects. Here, we present a hydrogel patch formed in a single step through dialysis. The exchange of DMSO into water facilitates hydrophobic aggregate in situ formation and the formation of hydrogen bonds within the hydrogel. Thanks to the optimized component ratio and precise structural design. The hydrogel patch has soft-tissue-like mechanical characteristics, including high strength, high toughness, low modulus similar to the abdominal wall, good fatigue resistance, and fast self-recovery properties. The nonswellable hydrogel patch retains over 80% of its original mechanical properties after 7 days of immersion in physiological saline, with a maximum swelling ratio of 5.6%. Moreover, the hydrophobic biomultifunctionality of benzyl isothiocyanate can self-assemble onto the hydrogel patch during the sol-gel transition process, enabling it to remodel the inflammatory microenvironment through synergistic antibacterial, antioxidant, and anti-inflammatory effects. The hydrogel patch prevents postsurgical adhesion in a rat sidewall defect-cecum abrasion model and outperforms the leading commercial Interceed. It holds promising potential for clinical translation, considering that FDA-approved raw materials (PVA and gelatin) form the backbone of this effective hydrogel patch.

Benzyl isothiocyanate as an alternative to antibiotics? a comparative in vivo study using Pseudomonas aeruginosa infection as a model

Due to over-prescription of antibiotics, antimicrobial resistance has emerged to be a critical concern globally. Many countries have tightened the control of antibiotic usage, which, in turn, promotes the search for alternatives to antibiotics. Quite a few phytochemicals have been investigated. Benzyl isothiocyanate (BITC) is an important secondary metabolite in cruciferous species and exhibited potent antimicrobial activity under in vitro conditions. In this research, we undertook a comparative mouse model study of BITC with gentamycin sulfate (positive antibiotic control) and ceftiofur hydrochloride (negative antibiotic control) against Pseudomonas aeruginosa infection. Our results showed that BITC exhibited comparable or better antimicrobial activity and lower infiltration of mouse immune cells upon comparing to gentamycin sulfate. Furthermore, BITC did not impose any toxicity to the air pouch skin tissues. In summary, our current study suggests that BITC could be an alternative to antibiotics and deserves further in vivo and clinical trial studies.

Isothiocyanates in medicine: A comprehensive review on phenylethyl-, allyl-, and benzyl-isothiocyanates

In recent years, isothiocyanates (ITCs), bioactive compounds primarily derived from Brassicaceae vegetables and herbs, have gained significant attention within the biomedical field due to their versatile biological effects. This comprehensive review provides an in-depth exploration of the therapeutic potential and individual biological mechanisms of the three specific ITCs phenylethyl isothiocyanate (PEITC), allyl isothiocyanate (AITC), and benzyl isothiocyanate (BITC), as well as their collective impact within the formulation of ANGOCIN® Anti-Infekt N (Angocin). Angocin comprises horseradish root (Armoracia rusticanae radix, 80 mg) and nasturtium (Tropaeoli majoris herba, 200 mg) and is authorized for treating inflammatory diseases affecting the respiratory and urinary tract. The antimicrobial efficacy of this substance has been confirmed both in vitro and in various clinical trials, with its primary effectiveness attributed to ITCs. PEITC, AITC, and BITC exhibit a wide array of health benefits, including potent anti-inflammatory, antioxidant, and antimicrobial properties, along with noteworthy anticancer potentials. Moreover, we highlight their ability to modulate critical biochemical pathways, such as the nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and signal transducer and activator of transcription (STAT) pathways, shedding light on their involvement in cellular apoptosis and their intricate role to guide immune responses.

Benzyl isothiocyanate inhibits TNFα-driven lipolysis via suppression of the ERK/PKA/HSL signaling pathway in 3T3-L1 adipocytes

Tumor necrosis factor α (TNFα), an inflammatory cytokine, induces lipolysis and increases circulating concentrations of free fatty acids. In addition, TNFα is the first adipokine produced by adipose tissue in obesity, contributing to obesity-associated metabolic disease. Given that benzyl isothiocyanate (BITC) is a well-known anti-inflammatory agent, we hypothesized that BITC can ameliorate TNFα-induced lipolysis and investigated the working mechanisms involved. We first challenged 3T3-L1 adipocytes with TNFα to induce lipolysis, which was confirmed by increased glycerol release, decreased protein expression of peroxisome proliferator-activated receptor γ (PPARγ) and perilipin 1 (PLIN1), and increased phosphorylation of ERK, protein kinase A (PKA), and hormone-sensitive lipase (HSL). However, inhibition of ERK or PKA significantly attenuated the lipolytic activity of TNFα. Meanwhile, pretreatment with BITC significantly ameliorated the lipolytic activity of TNFα; the TNFα-induced phosphorylation of ERK, PKA, and HSL; the TNFα-induced ubiquitination of PPARγ; the TNFα-induced decrease in PPARγ nuclear protein binding to PPAR response element; and the TNFα-induced decrease in PLIN1 protein expression. Our results indicate that BITC ameliorates TNFα-induced lipolysis by inhibiting the ERK/PKA/HSL signaling pathway, preventing PPARγ proteasomal degradation, and maintaining PLIN1 protein expression.

A monocentric, randomized, double-blind, controlled crossover trial of nasturtium (Tropaeolum majus) on the lipid regulator prostaglandin E2

Scope

As prostaglandin E2 (PGE2) has important roles in physiological and inflammatory functions, a double-blind randomized controlled crossover study to investigate the potential of nasturtium (Tropaeolum majus) for modulating PGE2 was conducted, aiming at clarifying the role of benzyl isothiocyanate (BITC). As secondary parameters leukotriene 4 (LTB4), and cytokine release (tumor necrosis factor alpha, TNF-α; interleukins IL-1β, IL-10, and IL-12) were quantified.

Methods and results

Thirty-four healthy female participants consumed 1.5 g nasturtium containing BITC, (verum) or no BITC (control) twice a day for 2 weeks each. Nasturtium intervention resulted in an increase in mean PGE2 levels in serum samples (verum: 1.76-fold, p ≤ 0.05; control: 1.78-fold, p ≤ 0.01), and ex vivo stimulated peripheral blood mononuclear cells (PBMC) (verum: 1.71-fold, p ≤ 0.01; control: 1.43-fold). Using a pre-to-post responder analysis approach, 18 of 34 subjects showed a > 25% PGE2 increase in serum, while it was >25% decreased for 9 subjects (stimulated PBMC: 14 and 8 of 28, respectively). Under the selected conditions, the BITC content of nasturtium did not affect the observed changes in PGE2. Verum intervention also increased mean LTB4 serum level (1.24-fold, p ≤ 0.01), but not in LPS stimulated PBMC, and significantly increased TNF-α release in stimulated PBMC after 3 h (verum: 1.65-fold, p = 0.0032; control: 1.22-fold, p = 0.7818). No change was seen in the anti-inflammatory cytokine IL-10, or the pro-inflammatory cytokines IL-1β, and IL-12.

Conclusion

In contrast to the previously reported in vitro results, on average, LPS activated PBMC and serum from both groups showed increased PGE2 levels. Further analyses suggest that PGE2 release after intervention could possibly depend on the baseline PGE2 level. Identification of phenotypes that respond differently to the nasturtium intervention could be useful to establish personalized approaches for dosing phytopharmaceuticals medicines.

(R)-8-Methylsulfinyloctyl isothiocyanate from Nasturtium officinale inhibits LPS-induced immunoinflammatory responses in mouse peritoneal macrophages: chemical synthesis and molecular signaling pathways involved

The aim of this study was to develop an optimal synthetic route to obtain natural (R)-8-methylsulfinyloctyl isothiocyanate ((R)-8-OITC), present in watercress, based on the "DAG methodology" as well as to evaluate its potential antioxidant and immunomodulatory effects, exploring possible signaling pathways that could be involved in an ex vivo model of murine peritoneal macrophages stimulated with LPS. Treatment with (R)-8-OITC inhibited the levels of pro-inflammatory cytokines (IL-1β, TNF-α, IL-6, IL-17 and IL-18), intracellular ROS production and expression of pro-inflammatory enzymes (COX-2, iNOS and mPGES-1) through modulation of the expression of Nrf2, MAPKs (p38, JNK and ERK) and JAK/STAT, and the canonical and non-canonical pathways of the inflammasome. Taking all these together, our results provide a rapid and cost-effective synthetic route to obtain natural (R)-8-OITC and demonstrate that it could be a potential nutraceutical candidate for managing immuno-inflammatory pathologies. Therefore, further in vivo trials are warranted.

Benzyl isothiocyanate attenuates activation of the NLRP3 inflammasome in Kupffer cells and improves diet-induced steatohepatitis

The NLRP3 inflammasome plays an important role in the pathogenesis of numerous inflammation-related diseases. Benzyl isothiocyanate (BITC) is rich in cruciferous vegetables and possesses potent antioxidant, anti-inflammatory, anti-cancer, and anti-obesogenic properties. In this study, we investigated the role of the NLRP3 inflammasome in the protection by BITC against steatohepatitis and insulin resistance. A mouse model of high-fat/cholesterol/cholic acid diet (HFCCD)-induced steatohepatitis, LPS/nigericin-stimulated primary Kupffer cells, and IL-1β treated primary hepatocytes were used. BITC attenuated LPS/nigericin-induced activation of the NLRP3 inflammasome by enhancing protein kinase A-dependent NLRP3 ubiquitination, which increased the degradation of NLRP3 and reduced IL-1β secretion in Kupffer cells. In hepatocytes, BITC pretreatment reversed the IL-1β-induced decrease in the phosphorylation of IR, AKT, and GSK3β in response to insulin. After 12 weeks of HFCCD feeding, increases in blood alanine aminotransferase (ALT) and glucose levels were ameliorated by BITC. Hepatic IL-1β production, macrophage infiltration, and collagen expression induced by HFCCD were also mitigated by BITC. BITC suppresses activation of the NLRP3 inflammasome in Kupffer cells by enhancing the PKA-dependent ubiquitination of NLRP3, which leads to suppression of IL-1β production and subsequently ameliorates hepatic inflammation and insulin resistance.

Benzyl isothiocyanate improves the prognosis of Aspergillus fumigatus keratitis by reducing fungal load and inhibiting Mincle signal pathway

Aspergillus fumigatus keratitis is a potential blinding disease associated with A. fumigatus invasion and excessive inflammatory response. Benzyl isothiocyanate (BITC) is a secondary metabolite with broad antibacterial and anti-inflammatory activity extracted from cruciferous species. However, the role of BITC in A. fumigatus keratitis has not been discovered yet. This study aims to explore the antifungal and anti-inflammatory effects and mechanisms of BITC in A. fumigatus keratitis. Our results provided evidences that BITC exerted antifungal effects against A. fumigatus by damaging cell membranes, mitochondria, adhesion, and biofilms in a concentration-dependent manner. In vivo, fungal load and inflammatory response including inflammatory cell infiltration and pro-inflammatory cytokine expression were reduced in BITC-treated A. fumigatus keratitis. Additionally, BITC significantly decreased Mincle, IL-1β, TNF-α, and IL-6 expression in RAW264.7 cells that stimulated by A. fumigatus or Mincle ligand trehalose-6,6-dibehenate. In summary, BITC possessed fungicidal activities and could improve the prognosis of A. fumigatus keratitis by reducing fungal load and inhibiting the inflammatory response mediated by Mincle.

Role of Sulfur Compounds in Vegetable and Mushroom Aroma

At the base of the food pyramid is vegetables, which should be consumed most often of all food products, especially in raw and unprocessed form. Vegetables and mushrooms are rich sources of bioactive compounds that can fulfill various functions in plants, starting from protection against herbivores and being natural insecticides to pro-health functions in human nutrition. Many of these compounds contain sulfur in their structure. From the point of view of food producers, it is extremely important to know that some of them have flavor properties. Volatile sulfur compounds are often potent odorants, and in many vegetables, belonging mainly to Brassicaeae and Allium (Amaryllidaceae), sulfur compounds determine their specific flavor. Interestingly, some of the pathways that form volatile sulfur compounds in vegetables are also found in selected edible mushrooms. The most important odor-active organosulfur compounds can be divided into isothiocyanates, nitriles, epithionitriles, thiols, sulfides, and polysulfides, as well as others, such as sulfur containing carbonyl compounds and esters, R-L-cysteine sulfoxides, and finally heterocyclic sulfur compounds found in shiitake mushrooms or truffles. This review paper summarizes their precursors and biosynthesis, as well as their sensory properties and changes in selected technological processes.

Benzyl Isothiocyanate-Induced Cytotoxicity via the Inhibition of Autophagy and Lysosomal Function in AGS Cells

Gastric adenocarcinoma is among the top causes of cancer-related death and is one of the most commonly diagnosed carcinomas worldwide. Benzyl isothiocyanate (BITC) has been reported to inhibit the gastric cancer metastasis. In our previous study, BITC induced apoptosis in AGS cells. The purpose of the present study was to investigate the effect of BITC on autophagy mechanism in AGS cells. First, the AGS cells were treated with 5, 10, or 15 μM BITC for 24 h, followed by an analysis of the autophagy mechanism. The expression level of autophagy proteins involved in different steps of autophagy, such as LC3B, p62/SQSTM1, Atg5-Atg12, Beclin1, p-mTOR/mTOR ratio, and class III PI3K was measured in the BITC-treated cells. Lysosomal function was investigated using cathepsin activity and Bafilomycin A1, an autophagy degradation stage inhibitor. Methods including qPCR, western blotting, and immunocytochemistry were employed to detect the protein expression levels. Acridine orange staining and omnicathepsin assay were conducted to analyze the lysosomal function. siRNA transfection was performed to knock down the LC3B gene. BITC reduced the level of autophagy protein such as Beclin 1, class III PI3K, and Atg5-Atg12. BITC also induced lysosomal dysfunction which was shown as reducing cathepsin activity, protein level of cathepsin, and enlargement of acidic vesicle. Overall, the results showed that the BITC-induced AGS cell death mechanism also comprises the inhibition of the cytoprotective autophagy at both initiation and degradation steps.

Role of Phytochemicals in Skin Photoprotection via Regulation of Nrf2

Ethnopharmacological studies have become increasingly valuable in the development of botanical products and their bioactive phytochemicals as novel and effective preventive and therapeutic strategies for various diseases including skin photoaging and photodamage-related skin problems including abnormal pigmentation and inflammation. Exploring the roles of phytochemicals in mitigating ultraviolet radiation (UVR)-induced skin damage is thus of importance to offer insights into medicinal and ethnopharmacological potential for development of novel and effective photoprotective agents. UVR plays a role in the skin premature aging (or photoaging) or impaired skin integrity and function through triggering various biological responses of skin cells including apoptosis, oxidative stress, DNA damage and inflammation. In addition, melanin produced by epidermal melanocytes play a protective role against UVR-induced skin damage and therefore hyperpigmentation mediated by UV irradiation could reflect a sign of defensive response of the skin to stress. However, alteration in melanin synthesis may be implicated in skin damage, particularly in individuals with fair skin. Oxidative stress induced by UVR contributes to the process of skin aging and inflammation through the activation of related signaling pathways such as the mitogen-activated protein kinase (MAPK)/activator protein-1 (AP-1), the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt), the nuclear factor kappa B (NF-κB) and the signal transducer and activator of transcription (STAT) in epidermal keratinocytes and dermal fibroblasts. ROS formation induced by UVR also plays a role in regulation of melanogenesis in melanocytes via modulating MAPK, PI3K/Akt and the melanocortin 1 receptor (MC1R)-microphthalmia-associated transcription factor (MITF) signaling cascades. Additionally, nuclear factor erythroid 2-related factor 2 (Nrf2)-regulated antioxidant defenses can affect the major signaling pathways involved in regulation of photoaging, inflammation associated with skin barrier dysfunction and melanogenesis. This review thus highlights the roles of phytochemicals potentially acting as Nrf2 inducers in improving photoaging, inflammation and hyperpigmentation via regulation of cellular homeostasis involved in skin integrity and function. Taken together, understanding the role of phytochemicals targeting Nrf2 in photoprotection could provide an insight into potential development of natural products as a promising strategy to delay skin photoaging and improve skin conditions.

Benzyl Isothiocyanate Attenuates Inflammasome Activation in Pseudomonas aeruginosa LPS-Stimulated THP-1 Cells and Exerts Regulation through the MAPKs/NF-κB Pathway

Inflammasomes are a group of intracellular multiprotein platforms that play important roles in immune systems. Benzyl isothiocyanate (BITC) is a constituent of cruciferous plants and has been confirmed to exhibit various biological activities. The modulatory effects of BITC on inflammasome-mediated interleukin (IL)-1β expression and its regulatory mechanisms in Pseudomonas aeruginosa (P. aeruginosa) LPS/ATP-stimulated THP-1 cells was investigated. Monocytic THP-1 cells were treated with phorbol myristate acetate (PMA) to induce differentiation into macrophages. Enzyme-linked immunosorbent assays (ELISA) were performed to measure the levels of IL-1β produced in P. aeruginosa LPS/ATP-exposed THP-1 cells. Western blotting was performed to examine the BITC modulatory mechanisms in inflammasome-mediated signaling pathways. BITC inhibited IL-1β production in P. aeruginosa LPS/ATP-induced THP-1 cells. BITC also inhibited activation of leucine-rich repeat protein-3 (NLRP3) and caspase-1 in P. aeruginosa LPS/ATP-induced THP-1 cells. Furthermore, we show that mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) activation in P. aeruginosa LPS was attenuated by BITC. These BITC-mediated modulatory effects on IL-1β production may have therapeutic potential for inflammasome-mediated disorders such as a nasal polyp.

Dauricine Attenuates Vascular Endothelial Inflammation Through Inhibiting NF-κB Pathway

Endothelial cells are the fundamental components of blood vessels that regulate several physiological processes including immune responses, angiogenesis, and vascular tone. Endothelial dysfunction contributes to the development of various diseases such as acute lung injury, and endothelial inflammation is a vital part of endothelial dysfunction. Dauricine is an extract isolated from Menispermum dauricum DC, a traditional Chinese medical plant that can be used for pharyngitis. In this work, we found that IL-1β-induced overexpression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and E-selectin was inhibited by dauricine in primary human umbilical vein endothelial cells (HUVECs). Correspondingly, adhesion of human acute monocytic leukemia cell line (THP-1) to HUVECs was decreased by dauricine. Further studies showed that dauricine inhibited the activation of nuclear factor-κB (NF-κB) pathway in HUVECs stimulated with IL-1β. In vivo, dauricine protected mice from lipopolysaccharide (LPS)-induced acute lung injury. In lung tissues, the activation of NF-κB pathway and the expression of its downstream genes (ICAM-1, VCAM-1, and E-selectin) were decreased by dauricine, consistent with what was found in vitro. In summary, we concluded that dauricine could alleviate endothelial inflammation by suppressing NF-κB pathway, which might serve as an effective candidate for diseases related with endothelial inflammation.

Characterization of Conjugates between α-Lactalbumin and Benzyl Isothiocyanate-Effects on Molecular Structure and Proteolytic Stability

In complex foods, bioactive secondary plant metabolites (SPM) can bind to food proteins. Especially when being covalently bound, such modifications can alter the structure and, thus, the functional and biological properties of the proteins. Additionally, the bioactivity of the SPM can be affected as well. Consequently, knowledge of the influence of chemical modifications on these properties is particularly important for food processing, food safety, and nutritional physiology. As a model, the molecular structure of conjugates between the bioactive metabolite benzyl isothiocyanate (BITC, a hydrolysis product of the glucosinolate glucotropaeolin) and the whey protein α-lactalbumin (α-LA) was investigated using circular dichroism spectroscopy, anilino-1-naphthalenesulfonic acid fluorescence, and dynamic light scattering. Free amino groups were determined before and after the BITC conjugation. Finally, mass spectrometric analysis of the BITC-α-LA protein hydrolysates was performed. As a result of the chemical modifications, a change in the secondary structure of α-LA and an increase in surface hydrophobicity and hydrodynamic radii were documented. BITC modification at the ε-amino group of certain lysine side chains inhibited tryptic hydrolysis. Furthermore, two BITC-modified amino acids were identified, located at two lysine side chains (K32 and K113) in the amino acid sequence of α-LA.

Benzyl isothiocyanate-modified α-lactalbumin - Two-dimensional high-performance thin-layer chromatography for analyzing modified peptides

In complex food matrices, non-directed reactions between food proteins and secondary plant metabolites (SPM) are conceivable. In this study, the interaction between the bioactive metabolite from garden cress (Lepidium sativum) and selected Brassicaceae - benzyl isothiocyanate (BITC) - and the dairy protein α-lactalbumin (α-LA) was investigated. It was focused on monitoring the proteolytic degradation behaviour of unmodified and BITC-modified α-LA with two-dimensional high-performance thin-layer chromatography (2D-HPTLC). The two-dimensional approach of HPTLC offers high resolution in the separation of complex peptide mixtures and might enable differentiation of protein modifications. Based on the specific peptide patterns of native and modified peptides, conclusions can be drawn about differences in protein/peptide polarity, location of a modification, and digestibility. The aim was to characterize tryptically hydrolyzed unmodified and BITC-modified peptides using the 2D method and to investigate the influence of BITC modification of α-LA on polarity and digestibility. To determine the repeatability of peptide separation by 2D-HPTLC, the unmodified and BITC-modified protein hydrolyzates were separated six times. The absolute standard deviations between the retardation factors of the individual peptide spots varied between 0.52 and 4.79 mm for the x-coordinates and between 0.41 and 6.47 mm for the y-coordinates for all three samples. Here, the mean relative standard deviations ranged from 5.80 to 10.4% for the x-coordinates and from 5.91 to 18.3% for the y-coordinates. The results of the tryptic hydrolysis indicated that, depending on the concentration of BITC used, the modification sterically hinders the cleavage sites for the enzyme, resulting in a reduced digestibility. Covalent binding of the hydrophobic BITC altered the digestibility and polarity of the protein, leading to a difference in peptide patterns between the unmodified and modified α-LA. It was concluded that the reaction was undirected, resulting in a mixture of unmodified and modified peptides, and that elongated modified peptides were formed by BITC blocking of trypsin cleavage sites.

Benzyl isothiocyanates modulate inflammation, oxidative stress, and apoptosis via Nrf2/HO-1 and NF-κB signaling pathways on indomethacin-induced gastric injury in rats

The present study investigated the gastroprotective activity of benzyl isothiocyanates (BITC) on indomethacin (IND)-induced gastric injury in a rat model and explicated the possible involved biochemical, cellular, and molecular mechanisms. The rat model with gastric ulcers was established by a single oral dose of IND (30 mg per kg b.wt). BITC (0.75 and 1.5 mg kg^-1) and esomeprazole (20 mg per kg b.wt) were orally administered for 3 weeks to rats before the induction of gastric injury. Compared with the IND group, BITC could diminish both the macroscopic and microscopic pathological morphology of gastric mucosa. BITC significantly preserved the antioxidants (glutathione GSH, superoxide dismutase SOD), nitric oxide (NO), and prostaglandin E2 (PGE2) contents, while decreasing the gastric mucosal malondialdehyde (MDA), tumor necrosis factor alpha (TNFα), and myeloperoxidase (MPO) contents. Moreover, BITC remarkably upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), hemoxygenase-1 (HO-1), and NAD(P)H : quinone oxidoreductase (NQO1). In addition, BITC activates the expression of heat shock protein 70 (HSP-70) and downregulated the expression of nuclear factor-κB (NF-κB) and caspase-3 to promote gastric mucosal cell survival. To the best of our knowledge, this study is the first published report to implicate the suppression of inflammation, oxidative stress, and Nrf2 signaling pathway as a potential mechanism for the gastroprotective activity of BITC.

Immunological Analysis of Isothiocyanate-Modified α-Lactalbumin Using High-Performance Thin Layer Chromatography

Undirected modifications between food proteins and secondary plant metabolites can occur during food processing. The results of covalent interactions can alter the functional and biological properties of the proteins. The present work studied the extent of which covalent conjugation of the bioactive metabolite benzyl isothiocyanate (BITC; a glucosinolate breakdown product) to the whey protein α-lactalbumin affects the protein’s allergenicity. Additional to the immunological analysis of native untreated and BITC-modified α-lactalbumin, the analysis of antigenic properties of proteolytically digested protein derivatives was also performed by high performance thin layer chromatography and immunostaining. As a result of the chemical modifications, structural changes in the protein molecule affected the allergenic properties. In this process, epitopes are destroyed or inactivated, but at the same time, buried epitopes can be exposed or newly formed, so that the net effect was an increase in allergenicity, in this case. Results from the tryptic hydrolysis suggest that BITC conjugation sterically hindered the cleavage sites for the enzyme, resulting in reduced digestibility and allergenicity. Residual antigenicity can be still present as short peptide fragments that provide epitopes. The desire to make food safer for allergy sufferers and to protect sensitized individuals from an allergenic reaction makes it clear that the detection of food antigens is mandatory; especially by considering protein interactions.

Assessment of benzyl isothiocyanate as an adjunct to conventional periodontal therapy

Background:

Conventional nonsurgical periodontal therapy eliminates the pathogenic microbes, yet residual deposits promote the recurrence of the disease. As antimicrobials may pose undesirable effects, alternate therapies are probed.

Aim:

The aim of the study is to evaluate the efficacy of locally delivered benzyl isothiocyanate (BITC) as an adjunct to scaling and root planing to treat patients with chronic periodontitis.

Materials and Methods:

The study included 30 patients diagnosed with chronic periodontitis. Test (scaling and root planing along with BITC intervention) and control (scaling and root planing) sites were randomly assigned to each patient. These sites were in the contralateral quadrants, having a probing depth of 4–6 mm. The plaque index (PI), gingival index (GI), pocket probing depth (PPD), clinical attachment level (CAL), and microbial load (colony forming unit [CFU]) were assessed at baseline, 1-week, and 6-week time interval. Data were analyzed by ANOVA/Friedman test, Mann–Whitney U-test, pairwise paired t-test, and Wilcoxon test, with P ≤ 0.05 set as statistically significant.

Results:

The scores of PI, GI, PPD, and CAL from baseline to 6-week follow-up within both the test and control sites were noted to be statistically significant (P < 0.0001). The CFU showed a significant reduction (P = 0.0229) within the test site at varying time intervals. The change in the mean PI score from baseline to 6-week time interval between the test and control site was noted to be statistically significant (P = 0.0039).

Conclusion:

The local application of BITC chips effectively reduced the PI, GI, PPD, and CFU, subsequently with the gain in CAL, and improved the tissue integrity and thereby oral hygiene.

[Uncomplicated urinary tract infections : Use of mustard oils]

BACKGROUND

Increasing rates of multidrug resistant bacteria demand a change in managing infectious diseases. New ways of antibiotic-free treatment in uncomplicated urinary tract infections (UTI) saving antibiotics for severe infections should be chosen.

OBJECTIVES

Beside analgesics for purely symptomatic treatment, herbal medicine can be used for uncomplicated UTI instead of antibiotics.

MATERIALS AND METHODS

Anti-infectious phytodrugs like isothiocyanates (ITC) from horseradish and cress (nasturtium) have been thoroughly examined scientifically.

RESULTS

ITC showed multitarget effects in many pharmacological studies. Beside anti-inflammatory effects, a broad spectrum of species, including multiresistant bacteria were covered. Positive results and good compatibility are documented in several studies for therapy of uncomplicated UTI and respiratory infections with horseradish and cress as well as for prophylaxis in recurrent UTI (recommendation in the German S3 guideline for uncomplicated urinary tract infections, AWMF registry 043/044, statement 8.1.d.4 on prophylaxis).

CONCLUSION

Using isothiocyanates (ITC) for therapy and prophylaxis in uncomplicated urinary tract infections is a rational approach and helps to save antibiotics. Even after long-term use, development of resistance has not yet been observed and is not probable due to the multimodal mechanism of action of ITC.

Therapeutic potential of sulfur-containing natural products in inflammatory diseases

Owing to the prevalence of chronic inflammation and its related disorders, there is a demand for novel therapeutic agents capable of preventing or suppressing inflammation. Natural products (NPs) are well established as an important resource for drug development and provide an almost infinite array of molecular entities. Sulfur-containing NPs (i.e., NPs containing one or more sulfur atoms) are abundant throughout nature, from bacteria to animals. The aim of this review was to survey the emerging evidence on role of sulfur-containing NPs, such as glutathione, garlic-derived sulfur compounds, Epipolythiodioxopiperazines (EPTs), Isothiocyanates (ITCs), and Ergothioneine (EGT), in the control of inflammation and to determine the possible underlying mechanisms. A discussion of how hydrogen sulfide (H₂S), an endogenous gaseous signaling molecule, links sulfur-containing NPs and their anti-inflammatory action is also performed. This review may help to further the development of sulfur-based compounds by providing a guide for structure-activity relationship-based modification for use in modern medicinal chemistry. However, as this field is still in its infancy, the review is concluded by an overview of the progression of these promising entities as therapeutic agents.

Mechanisms Underlying Biological Effects of Cruciferous Glucosinolate-Derived Isothiocyanates/Indoles: A Focus on Metabolic Syndrome

An inverse correlation between vegetable consumption and the incidence of cancer has long been described. This protective effect is stronger when cruciferous vegetables are specifically consumed. The beneficial properties of vegetables are attributed to their bioactive components like fiber, antioxidants vitamins, antioxidants, minerals, and phenolic compounds. Cruciferous vegetables contain all these molecules; however, what makes them different are their sulfurous components, called glucosinolates, responsible for their special smell and taste. Glucosinolates are inactive biologically in the organism but are hydrolyzed by the enzyme myrosinase released as a result of chewing, leading to the formation of active derivatives such as isothiocyanates and indoles. A considerable number of in vitro and in vivo studies have reported that isothiocyanates and indoles elicit chemopreventive potency through multiple mechanisms that include modulation of phases I and II detoxification pathway enzymes, regulation of cell cycle arrest, and control of cell growth, induction of apoptosis, antioxidant activity, anti-angiogenic effects, and epigenetic regulation. Nuclear erythroid 2-related factor 2 (Nrf2) and Nuclear factor-κB (NF-κB) are key and central regulators in all these processes with a main role in oxidative stress and inflammation control. It has been described that isothiocyanates and indoles regulate their activity directly and indirectly. Today, the metabolic syndrome (central obesity, insulin resistance, hyperlipidemia, and hypertension) is responsible for a majority of deaths worldwide. All components of metabolic syndrome are characterized by chronic inflammation with deregulation of the PI3K/AKT/mTOR, MAPK/EKR/JNK, Nrf2, and NF-κB signaling pathways. The effects of GLSs derivatives controlling these pathways have been widely described in relation to cancer. Changes in food consumption patterns observed in the last decades to higher consumption of ultra-processed foods, with elevation in simple sugar and saturated fat contents and lower consumption of vegetables and fruits have been directly correlated with metabolic syndrome prevalence. In this review, it is summarized the knowledge regarding the mechanisms by which cruciferous glucosinolate derivatives (isothiocyanates and indoles) directly and indirectly regulate these pathways. However, the review places a special focus on the knowledge of the effects of glucosinolates derivatives in metabolic syndrome, since this has not been reviewed before.

Moringin and Its Structural Analogues as Slow H2S Donors: Their Mechanisms and Bioactivity

Moringin (rhamnobenzyl isothiocyanate) is a major bioactive compound in moringa seeds, which have been used as a healthy food. However, its bioactivity mechanisms are not well understood. We investigated moringin and its structurally similar analogues, including benzyl isothiocyanate and 4-hydroxylbenzyl isothiocyanate, for their hydrogen sulfide (H₂S)-releasing activity triggered by cysteine. These isothiocyanates rapidly formed cysteine adducts, which underwent intramolecular cyclization followed by slowly releasing (a) organic amine and raphanusamic acid and (b) H₂S and 2-carbylamino-4,5-dihydrothiazole-4-carboxylic acids. The product distributions are highly dependent on para-substituents on the phenyl group. Moringin has higher cytotoxicity to cancer cells and is a more potent anti-inflammatory agent than benzyl and hydroxybenzyl analogues, while benzyl isothiocyanate is a better antibacterial agent. Taken together, their bioactivity may not be directly related to their H₂S donation activity. However, other metabolites alone do not have cytotoxicity and anti-inflammatory activity. These findings indicated that their activity may be the combination effects of different metabolites via competitive pathways as well the para-substituent groups of benzyl ITCs.

Benzyl Isothiocyanate Induces Apoptosis via Reactive Oxygen Species-Initiated Mitochondrial Dysfunction and DR4 and DR5 Death Receptor Activation in Gastric Adenocarcinoma Cells

Benzyl isothiocyanate (BITC) is known to inhibit the metastasis of gastric cancer cells but further studies are needed to confirm its chemotherapeutic potential against gastric cancer. In this study, we observed cell shrinkage and morphological changes in one of the gastric adenocarcinoma cell lines, the AGS cells, after BITC treatment. We performed 3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2H-tetrazolium bromide (MTT) assay, a cell viability assay, and found that BITC decreased AGS cell viability. Reactive oxygen species (ROS) analyses using 2',7'-dichlorofluorescin diacetate (DCFDA) revealed that BITC-induced cell death involved intracellular ROS production, which resulted in mitochondrial dysfunction. Additionally, cell viability was partially restored when BITC-treated AGS cells were preincubated with glutathione (GSH). Western blotting indicated that BITC regulated the expressions of the mitochondria-mediated apoptosis signaling molecules, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), and cytochrome c (Cyt c). In addition, BITC increased death receptor DR5 expression, and activated the cysteine-aspartic proteases (caspases) cascade. Overall, our results showed that BITC triggers apoptosis in AGS cells via the apoptotic pathways involved in ROS-promoted mitochondrial dysfunction and death receptor activation.

Benzyl Isothiocyanate and Phenethyl Isothiocyanate Inhibit Adipogenesis and Hepatosteatosis in Mice with Obesity Induced by a High-Fat Diet

Benzyl isothiocyanate (BITC) and phenethyl isothiocyanate (PEITC) are organosulfur phytochemicals rich in cruciferous vegetables. We investigated the antiobesity and antihepatosteatosis activities of BITC and PEITC and the working mechanisms involved. C57BL/6J mice were fed a low-fat diet (LFD), a high-fat diet (HFD), or a HFD supplemented with 0.5 (L) or 1 g/kg (H) BITC or PEITC for 18 weeks. Compared with the HFD group, BITC or PEITC decreased the final body weight of mice in a dose-dependent manner [39.0 ± 3.1 (HFD), 34.4 ± 3.2 (BITC-L), 32.4 ± 2.8 (BITC-H), 36.2 ± 4.4 (PEITC-L), and 32.8 ± 2.9 (PEITC-H) g, p < 0.05], relative weight of epididymal fat [5.7 ± 0.4 (HFD), 4.7 ± 0.7 (BITC-L), 3.7 ± 0.3 (BITC-H), 4.4 ± 1.0 (PEITC-L), and 3.2 ± 0.6 (PEITC-H) %, p < 0.05], hepatic triglycerides [98.4 ± 6.0 (HFD), 81.0 ± 8.9 (BITC-L), 63.5 ± 5.6 (BITC-H), 69.3 ± 5.6 (PEITC-L), and 49.4 ± 2.9 (PEITC-H) mg/g, p < 0.05], and plasma total cholesterol [140 ± 21.3 (HFD), 109 ± 5.6 (BITC-L), 101 ± 11.3 (BITC-H), 126 ± 8.3 (PEITC-L), and 91.8 ± 12.7 (PEITC-H) mg/dL, p < 0.05]. Q-PCR and immunoblotting assays revealed that BITC and PEITC suppressed the expression of liver X receptor α, sterol regulatory element-binding protein 1c, stearoyl-CoA desaturase 1, fatty acid synthase, and acetyl-CoA carboxylase in both epididymal adipose and liver tissues. After a single oral administration of 85 mg/kg BITC or PEITC, the maximum plasma concentrations ( C_max) of BITC and PEITC were 5.8 ± 2.0 μg/mL and 4.3 ± 1.9 μg/mL, respectively. In 3T3-L1 adipocytes, BITC and PEITC dose-dependently reduced adipocyte differentiation and cell cycle was arrested in G0/G1 phase. These findings indicate that BITC and PEITC ameliorate HFD-induced obesity and fatty liver by down-regulating adipocyte differentiation and the expression of lipogenic transcription factors and enzymes.

In Vitro Determination of Protein Conjugates in Human Cells by LC-ESI-MS/MS after Benzyl Isothiocyanate Exposure

Glucosinolates and their breakdown products, especially isothiocyanates (ITCs), are hypothesized to exert a broad range of bioactivities. However, physiological mechanisms are not yet completely understood. In this study, formation of protein conjugates after incubation with benzyl isothiocyanate (BITC) was investigated in vitro. A survey of protein conjugates was done by determining BITC cysteine and lysine amino acid conjugates after protein digestion. Therefore, a liquid chromatography-tandem mass spectrometry (LC-ESI-MS/MS) method was developed and validated. Stability studies showed that cysteine conjugates are not stable under alkaline conditions, and lysine conjugates did not show any correlation to pH values, although stability increased at low temperatures. Lysine conjugates were the preferred form of protein conjugates, and longer BITC exposure times led to higher amounts. Knowledge about the reaction sites of ITCs in eukaryotic cells may help to understand the mode of action of ITCs leading to health promoting as well as toxicological effects in humans.

Brassica-Derived Plant Bioactives as Modulators of Chemopreventive and Inflammatory Signaling Pathways

A high consumption of vegetables belonging to the Brassicaceae family has been related to a lower incidence of chronic diseases including different kinds of cancer. These beneficial effects of, e.g., broccoli, cabbage or rocket (arugula) intake have been mainly dedicated to the sulfur-containing glucosinolates (GLSs)-secondary plant compounds nearly exclusively present in Brassicaceae-and in particular to their bioactive breakdown products including isothiocyanates (ITCs). Overall, the current literature indicate that selected Brassica-derived ITCs exhibit health-promoting effects in vitro, as well as in laboratory mice in vivo. Some studies suggest anti-carcinogenic and anti-inflammatory properties for ITCs which may be communicated through an activation of the redox-sensitive transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) that controls the expression of antioxidant and phase II enzymes. Furthermore, it has been shown that ITCs are able to significantly ameliorate a severe inflammatory phenotype in colitic mice in vivo. As there are studies available suggesting an epigenetic mode of action for Brassica-derived phytochemicals, the conduction of further studies would be recommendable to investigate if the beneficial effects of these compounds also persist during an irregular consumption pattern.

BITC and S-Carvone Restrain High-Fat Diet-Induced Obesity and Ameliorate Hepatic Steatosis and Insulin Resistance

PURPOSE

To investigate the preventative activity of benzyl isothiocyante and S-carvone against high-fat diet-induced obesity and metabolic complications.

METHODS

Ten-week-old C57BL/6 male mice were fed a high-fat diet and injected intraperitoneally twice per week with benzyl isothiocyante, S-carvone, or vehicle for 8 weeks. The body weight, food intake, and body composition were monitored, and glucose tolerance and insulin tolerance tests were performed at the end of the experiment. Serum and tissue samples were studied using serum biochemistry, histological, and gene expression analysis to define the effects of benzyl isothiocyante and S-carvone treatments on lipid and glucose metabolism and inflammatory responses.

RESULTS

Benzyl isothiocyante and S-carvone blocked high-fat diet-induced weight gain, fat accumulation in the liver, and insulin resistance. The beneficial effects were found to be associated with an improvement of expression of macrophage marker genes in white adipose tissue, including F4/80, Cd11b, Cd11c, Cd206, and Tnf-α, and reduced expression of genes (Pparγ2, Scd1, Cd36) responsible for lipid synthesis and transport in the liver.

CONCLUSION

Benzyl isothiocyante and S-carvone block high-fat diet-induced obesity and metabolism disorders and can be considered for management of the obesity epidemic that affects approximately 36% of adults and 17% of children in the USA.

Cytokine Attenuation and Free Radical Scavenging Activity of a New Flavanone7,4'-Dihydroxy-3″,3″-Dimethyl -(5,6-Pyrano-2″-One)- 8- (3‴,3‴-Dimethyl Allyl)- Isolated from Mallotus philippensis: Possible Mechanism for Its Anti-Inflammatory Activity

Mallotus philippensis L.(MP) commonly known as Kamala tree in Hindi,is a small to medium-sized monoecious tree.The objective of the study was to evaluate the anti-inflammatory activity of MPand a new flavanoneisolated from it by using in vivo models of inflammation.Albino wistar rats of either sex weighing 150-200g were used. Seven groups were made (n = 6), namely normal control group (normal saline, 1 ml/kg), standard control group (acetylsalicylic acid, 100 mg/kg), methanol crude extract (300 and 500 mg/kg), ethylacetate fraction (300 and 500 mg/kg) and active compound 4 (new flavanone, 50 mg/kg). The anti-inflammatory activity was studied using carrageenan induced paw edema method and cotton pellet granuloma method. Levels of cytokines (TNF-α, IL-1and IL-6) and activity of antioxidant enzymeslike catalase and glutathione peroxidase were estimated. It was found that the methanol extract, ethylacetate fraction and Flavanonedemonstrated significant reduction in paw edema in carrageenan induced paw edema method as compared to control. They also diminished the serum TNF-α, IL-6 and IL-1 levels. Significantly attenuated the malondialdehyde levels and increased the activities of catalase and glutathione peroxidase in paw tissue. Similarly there was asignificant decrease in granuloma formation in cotton pellet induced granuloma method. In conclusion, MP extracts and the newflavanonepossess anti-inflammatory activity and this might be due to the inhibition of various cytokines and increased free radical scavenging activity.

Anti-inflammatory and immunomodulatory properties of Carica papaya

Chronic inflammation is linked with the generation and progression of various diseases such as cancer, diabetes and atherosclerosis, and anti-inflammatory drugs therefore have the potential to assist in the treatment of these conditions. Carica papaya is a tropical plant that is traditionally used in the treatment of various ailments including inflammatory conditions. A literature search was conducted by using the keywords "papaya", "anti-inflammatory and inflammation" and "immunomodulation and immune" along with cross-referencing. Both in vitro and in vivo investigation studies were included. This is a review of all studies published since 2000 on the anti-inflammatory activity of papaya extracts and their effects on various immune-inflammatory mediators. Studies on the anti-inflammatory activities of recognized phytochemicals present in papaya are also included. Although in vitro and in vivo studies have shown that papaya extracts and papaya-associated phytochemicals possess anti-inflammatory and immunomodulatory properties, clinical studies are lacking.

Benzyl isothiocyanate inhibits inflammasome activation in E. coli LPS-stimulated BV2 cells

Inflammasomes are multi-protein complexes that play a crucial role in innate immune responses. Benzyl isothiocyanate (BITC) is a naturally occurring compound found in cruciferous vegetables, and BITC exhibits potential as a chemopreventive agent. However, whether BITC exerts inflammasome-mediated regulatory effects on neuroinflammation is unknown. In this study, we examined the effects of BITC on inflammasome-mediated interleukin-1β (IL-1β) production in E. coli lipopolysaccharide (LPS)-stimulated BV2 microglial cells. IL-1β production is tightly regulated at the post-translational level through the inflammasoume. We measured the levels of IL-1β produced from the LPS-exposed BV2 microglial cells using enzyme-linked immunosorbent assays (ELISAs). The BITC regulatory mechanisms in inflammasome-mediated cellular signaling pathways were examined by RT-PCR, western blot analysis and electrophoretic mobility shift assays. BITC inhibited the secretion of IL-1β induced by LPS in the BV2 microglial cells. BITC inhibited inflammasome activation and NLR family, pyrin domain containing 3 (NLRP3)-mediated caspase-1 activation, and decreased the levels of inflammasome activation pro-inflammatory mediators, including mitochondrial reactive oxygen species (ROS) and adenosine triphosphate (ATP) secretion in the LPS-stimulated BV2 microglial cells. Furthermore, we demonstrated that nuclear factor-κB (NF-κB) activation induced by LPS was inhibited by BITC, which may contribute to the attenuated secretion of IL-1β. These BITC-mediated inhibitory effects on IL-1β expression may thus regulate neuroinflammation through the inflammasome-mediated signaling pathway.

Nasturtium (Indian cress, Tropaeolum majus nanum) dually blocks the COX and LOX pathway in primary human immune cells

BACKGROUND

Nasturtium (Indian cress, Tropaeolum majus) is known for its pharmacological value in the treatment of bacterial infections of the upper air tract and urinary bladder. However, scientific data on the anti-inflammatory potency in human-derived cells is missing.

PURPOSE

The aim of this study was to investigate the potential of nasturtium to inhibit the lipopolysaccharide (LPS) induced inflammatory response in primary human cells of the immune system.

STUDY DESIGN

The anti-inflammatory activities of nasturtium and its fractions were evaluated via regulation of arachidonic acid (AA) pathway and MAPK kinase cascade. Fraction H4 which was responsible for the anti-inflammatory effects was further characterized.

METHODS

Human peripheral blood mononuclear cells (PBMC) were either treated with plant extracts or fractions thereof, stimulated with LPS and/or N-formyl-methionyl-leucyl-phenylalanine (fMLP) and analysed for COX and LOX, release of prostaglandin PGE2, leukotriene LTB4, TNF-alpha and ERK signaling pathway activation. The plant extracts were separated into four fractions by HPLC; fraction H4 was subjected to UHPLC-ToF/MS analysis to identify potential bioactive compounds.

RESULTS

We found that aqueous extracts of nasturtium did exert strong concentration dependent suppression of LPS-triggered TNF-alpha release and COX pathway signaling, including PGE2 synthesis. Whereas COX-1 protein expression was not impacted, LPS-triggered COX-2 protein expression was concentration dependently blocked by the plant extract but not COX-2 enzyme activity. These findings suggest a mechanism of action for the plant extract which is different from non-steroidal anti-inflammatory drugs (NSAIDs). Moreover, the plant extract blocked leukotriene LTB4 release, the major end product of the 5-LOX pathway from PBMC. Down-regulation of ERK1/2 and c-Jun activation preceded COX-2 suppression upon plant extract treatment in the presence of LPS. Using HPLC separation of the aqueous extract followed by metabolomic analysis we could limit the number of relevant bioactive compounds in the extract to about 50.

CONCLUSIONS

This study provides a rationale for the anti-inflammatory efficacy of nasturtium observed in man and gives first insight into the underlying molecular mechanisms.

Anti-inflammatory activity of roots of Cichorium intybus due to its inhibitory effect on various cytokines and antioxidant activity

BACKGROUND

Cichorium intybus L. commonly known as chicory is one of the important medicinal plants commonly used in Ayurvedic system of medicine. It is commonly used for the treatment of diseases involving a khapa and pitta doshas. Traditionally, C. intybus is used for the treatment of inflammatory conditions, but there are only few in vitro studies reporting the anti-inflammatory activity of roots of chicory.

OBJECTIVE

Evaluation of anti-inflammatory activity of roots of chicory and mechanisms involved in it using in vivo models of inflammation.

MATERIALS AND METHODS

Albino Wistar rats of either sex weighing 150-200 g were used. Ethanolic and aqueous extracts of roots of chicory were prepared with the help of Soxhlet's apparatus. The anti-inflammatory activity was studied using carrageenan-induced paw edema method and cotton pellet granuloma method. Levels of cytokines such as tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and IL-1 and activity of antioxidant enzymes such as catalase (CAT) and glutathione peroxidase (GPx) were estimated.

RESULTS

Chicory roots demonstrated significant dose-dependent decrease in paw edema in carrageenan-induced paw edema method. Chicory roots diminished the serum TNF-α, IL-6, and IL-1 levels. They also significantly attenuated the malonylaldehyde levels and increased the activities of CAT and GPx in paw tissue. Similarly, chicory roots demonstrated a significant decrease in granuloma formation in cotton pellet induced granuloma method.

CONCLUSION

Chicory roots possess anti-inflammatory activity, and this might be due to the inhibition of various cytokines, antioxidant effects, and their free radical scavenging activity.

Sulforaphane and its methylcarbonyl analogs inhibit the LPS-stimulated inflammatory response in human monocytes through modulating cytokine production, suppressing chemotactic migration and phagocytosis in a NF-κB- and MAPK-dependent manner

Sulforaphane [SF; 1-isothiocyanato-4-(methylsulfinyl)-butane], an aliphatic isothiocyanate (ITC) naturally derived from cruciferous vegetables and largely known for its chemopreventive potential also appears to possess anti-inflammatory potential. In this study, structural analogs of SF {compound 1 [1-isothiocyanato-4-(methylcarbonyl)-butane] and 2 [1-isothiocyanato-3-(methylcarbonyl)-propane]} containing a carbonyl group in place of the sulfinyl group in SF, were evaluated for their anti-inflammatory activities. In RAW 264.7 cells, the ITCs at non-toxic concentrations caused an inhibition of NO and prostaglandin E2 (PGE2) release through suppressing expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), as well as a reduction in matrix metalloproteinase-9 (MMP-9) expression, secretion and gelatinolytic activity. Further work performed on human monocytes isolated from blood of healthy donors revealed that the ITCs not only suppressed the expression and release of pro-inflammatory mediators IL-1β, IL-6, TNF-α and MMP-9, but also suppressed their antibody-independent phagocytic and chemotactic migratory abilities. These anti-inflammatory activities were mediated through suppression of the NF-κB and MAPK signaling pathways. In addition, the ITCs were revealed to interact with the cysteines in inhibitor of nuclear factor-κB kinase β subunit (IKKβ), which could contribute at least partly to the suppression of NF-κB signaling. In conclusion, results obtained in this study provide deeper insights into the anti-inflammatory properties of SF and its methylcarbonyl analogs and the underlying mechanisms. These compounds thus serve as promising candidates for clinical applications in controlling inflammatory conditions.

Oxyresveratrol suppresses lipopolysaccharide-induced inflammatory responses in murine macrophages

Excessive inflammation is considered a critical factor in many human diseases. Oxyresveratrol(trans-2,3',4,5'-tetrahydroxystilbene), a natural hydroxystilbene, has been shown to possess antioxidant and free radical-scavenging activity. In this study, we investigated the effects of oxyresveratrol (OxyR) on the lipopolysaccharide (LPS)-induced production of inflammatory cytokines and mediators and further explored the mechanism of action in RAW264.7 murine macrophage cell line. Production of nitric oxide (NO), prostaglandin E2 (PGE2), messenger RNA (mRNA) and protein expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin 6 (IL-6), and granulocyte macrophage colony-stimulating factor (GM-CSF), phosphorylation of mitogen-activated protein kinases (MAPKs; extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38), and the activation of nuclear factor κ-light chain enhancer of activated B cells (NFκB) with OxyR were assayed in LPS-stimulated RAW264.7 cells. OxyR inhibited the productions of NO, PGE2, IL-6, and GM-CSF significantly in LPS-stimulated RAW264.7 cells. OxyR suppressed mRNA and protein expressions of iNOS, COX-2, IL-6, and GM-CSF in LPS-stimulated RAW264.7 cells. OxyR suppressed the phosphorylation of Akt and JNK and p38 MAPKs and the translocation of NFκB p65 subunit into the nucleus. These results indicate that OxyR inhibits LPS-stimulated inflammatory responses though the blocking of MAPK and NFκB signaling pathway in macrophages, and suggest that OxyR possesses anti-inflammatory effects.

Berteroin present in cruciferous vegetables exerts potent anti-inflammatory properties in murine macrophages and mouse skin

Berteroin (5-methylthiopentyl isothiocyanate) is a sulforaphane analog present in cruciferous vegetables, including Chinese cabbage, rucola salad leaves, and mustard oil. We examined whether berteroin exerts anti-inflammatory activities using lipopolysaccharide (LPS)-stimulated Raw 264.7 macrophages and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin inflammation models. Berteroin decreased LPS-induced release of inflammatory mediators and pro-inflammatory cytokines in Raw 264.7 macrophages. Berteroin inhibited LPS-induced degradation of inhibitor of κBα (IκBα) and nuclear factor-κB p65 translocation to the nucleus and DNA binding activity. Furthermore, berteroin suppressed degradation of IL-1 receptor-associated kinase and phosphorylation of transforming growth factor β activated kinase-1. Berteroin also inhibited LPS-induced phosphorylation of p38 MAPK, ERK1/2, and AKT. In the mouse ear, berteroin effectively suppressed TPA-induced edema formation and down-regulated iNOS and COX-2 expression as well as phosphorylation of AKT and ERK1/2. These results demonstrate that berteroin exhibits potent anti-inflammatory properties and suggest that berteroin can be developed as a skin anti-inflammatory agent.

'Moringa oleifera: study of phenolics and glucosinolates by mass spectrometry'

Moringa oleifera is a medicinal plant and an excellent dietary source of micronutrients (vitamins and minerals) and health-promoting phytochemicals (phenolic compounds, glucosinolates and isothiocyanates). Glucosinolates and isothiocyanates are known to possess anti-carcinogenic and antioxidant effects and have attracted great interest from both toxicological and pharmacological points of view, as they are able to induce phase 2 detoxification enzymes and to inhibit phase 1 activation enzymes. Phenolic compounds possess antioxidant properties and may exert a preventative effect in regards to the development of chronic degenerative diseases. The aim of this work was to assess the profile and the level of bioactive compounds in all parts of M. oleifera seedlings, by using different MS approaches. First, flow injection electrospray ionization mass spectrometry (FI-ESI-MS) fingerprinting techniques and chemometrics (PCA) were used to achieve the characterization of the different plant's organs in terms of profile of phenolic compounds and glucosinolates. Second, LC-MS and LC-MS/MS qualitative and quantitative methods were used for the identification and/or determination of phenolics and glucosinolates in M. oleifera.

Benzyl isothiocyanate suppresses high-fat diet-stimulated mammary tumor progression via the alteration of tumor microenvironments in obesity-resistant BALB/c mice

We previously reported that a high-fat diet (HFD) and M2-macrophages induce changes in tumor microenvironments and stimulate tumor growth and metastasis of 4T1 mammary cancer cells in BALB/c mice. In this study, we attempted to determine whether benzyl isothiocyanate (BITC) inhibits HFD-induced changes in tumor progression and in tumor microenvironments. Four groups of female BALB/c mice (4-week-old) were fed on a control diet (CD, 10 kcal% fat) and HFD (60 kcal% fat) containing BITC (0, 25, or 100 mg/kg diet) for 20 weeks. Following 16 weeks of feeding, 4T1 cells (5×10(4) cells) were injected into the mammary fat pads, and animals were killed 30 d after the injection. HFD feeding increased solid tumor growth and the number of tumor nodules in the lung and liver, as compared to the CD group, and these increases were inhibited by BITC supplementation. The number of lipid vacuoles, CD45+ leukocytes and CD206+ M2-macrophages, expression of Ki67, levels of cytokines/chemokines, including macrophage-colony stimulating factor (M-CSF) and monocyte chemoattractant protein-1, and mRNA levels of F4/80, CD86, Ym1, CD163, CCR2, and M-CSF receptor were increased in the tumor tissues of HFD-fed mice, and these increases were inhibited by BITC supplementation. In vitro culture results demonstrated that BITC inhibited macrophage migration as well as lipid droplet accumulation in 3T3-L1 cells. These results suggest that suppression of lipid accumulation and macrophage infiltration in tumor tissues may be one of the mechanisms by which BITC suppresses tumor progression in HFD-fed mice.

Erucin exerts anti-inflammatory properties in murine macrophages and mouse skin: possible mediation through the inhibition of NFκB signaling

Erucin, an isothiocyanate, is a hydrolysis product of glucoerucin found in arugula and has recently been reported to have anti-cancer properties in various cancer cells. In this study, we assessed the anti-inflammatory effects of erucin and the underlying mechanisms, using lipopolysaccharide (LPS)-stimulated RAW 264.7 murine macrophages and 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin. In RAW 264.7 cells, erucin (2.5, 5 μmol/L) inhibited LPS-induced production of nitric oxide and prostaglandin E₂. Erucin inhibited LPS-induced degradation of the inhibitor of κBα and translocation of p65 to the nucleus and, subsequently, reduced LPS-induced nuclear factor κB (NFκB) DNA binding activities, as well as the transcriptional activity of NFκB, leading to the decreased expression of NFκB-target genes, including tumor necrosis factor-α, interleukin (IL)-6, IL-1β, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, as well as transcriptional activity of iNOS and COX-2. In mice, erucin (100, 300 nmoles) treatment significantly inhibited phorbol ester-induced formation of ear edema and expression of iNOS and COX-2 proteins. These results indicate that erucin exerts a potent anti-inflammatory activity by inhibiting the pro-inflammatory enzymes and cytokines, which may be mediated, at least in part, via the inhibition of NFκB signaling.

The anti-inflammatory effects of platinum nanoparticles on the lipopolysaccharide-induced inflammatory response in RAW 264.7 macrophages

OBJECTIVE

Platinum nanoparticles (nano-Pt) have been reported to possess anti-oxidant and anti-tumor activities. However, the biological activity and mechanism of action of nano-Pt in inflammation are still unknown. The present study was designed to determine the in-vitro anti-inflammatory effects of nano-Pt on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells.

METHODS

RAW 264.7 macrophages were used for the study. The LPS-induced production of reactive oxygen species (ROS) was determined by flow cytometry. The prostaglandin E(2) (PGE(2)) concentration was measured using a PGE(2) assay kit. The protein levels and mRNA expression of the pro-inflammatory cytokines [tumor necrosis factor-α, interleukin (IL)-1β and IL-6], along with cyclooxygenase (COX-2) and inducible nitric oxide synthase, were analyzed by Western blotting and reverse transcription-polymerase chain reaction analysis. The phosphorylation of extracellular signal regulated kinase (ERK1/2) and Akt, and the phosphorylation and degradation of inhibitory kappa B-alpha (IκB-α) was determined by Western blot analysis.

RESULTS

Nano-Pt significantly reduced the LPS-induced production of intracellular ROS and inflammatory mediators. In addition, nano-Pt suppressed the phosphorylation of ERK1/2 and Akt, and significantly inhibited the phosphorylation/degradation of IκB-α as well as nuclear factor kappa-B (NFκB) transcriptional activity.

CONCLUSION

These results suggest that the anti-inflammatory properties of nano-Pt may be attributed to their downregulation of the NFκB signaling pathway in macrophages, thus supporting the use of nano-Pt as an anti-inflammatory agent.

Isothiocyanates inhibit psoriasis-related proinflammatory factors in human skin

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Inhibition of lipopolysaccharide-induced cyclooxygenase-2 and inducible nitric oxide synthase expression by 4-[(2'-O-acetyl-α-L-rhamnosyloxy)benzyl]isothiocyanate from Moringa oleifera

Moringa oleifera Lamarck is commonly consumed for nutritional or medicinal properties. We recently reported the isolation and structure elucidation of novel bioactive phenolic glycosides, including 4-[(2'-O-acetyl-α-L-rhamnosyloxy)benzyl]isothiocyanate (RBITC), which was found to suppress inducible nitric oxide synthase (iNOS) expression and nitric oxide (NO) production in lipopolysaccharide-stimulated RAW 264.7 mouse macrophage cells. Inhibitors of proteins such as cyclooxygenase-2 (COX-2) and iNOS are potential antiinflammatory and cancer chemopreventive agents. The inhibitory activity of RBITC on NO production (IC(50) = 0.96 ± 0.23 μM) was greater than that mediated by other well-known isothiocyanates such as sulforaphane (IC(50) = 2.86 ± 0.39 μM) and benzyl isothiocyanate (IC(50) = 2.08 ± 0.28 μM). RBITC inhibited expression of COX-2 and iNOS at both the protein and mRNA levels. Major upstream signaling pathways involved mitogen-activated protein kinases and nuclear factor-κB (NF-κB). RBITC inhibited phosphorylation of extracellular signal-regulated kinase and stress-activated protein kinase, as well as ubiquitin-dependent degradation of inhibitor κBα (IκBα). In accordance with IκBα degradation, nuclear accumulation of NF-κB and subsequent binding to NF-κB cis-acting element was attenuated by treatment with RBITC. These data suggest RBITC should be included in the dietary armamentarium of isothiocyanates potentially capable of mediating antiinflammatory or cancer chemopreventive activity.

Betulinic acid inhibits endotoxin-stimulated phosphorylation cascade and pro-inflammatory prostaglandin E(2) production in human peripheral blood mononuclear cells

BACKGROUND AND PURPOSE

Betulinic acid (BA) is a naturally occurring triterpenoid widely distributed throughout the plant kingdom. We previously reported that BA inhibits lipopolysaccharide (LPS)-induced interleukin-6 production through modulation of nuclear factor κB (NF-κB) in human peripheral blood mononuclear cells (hPBMCs). This study attempted to identify other mechanisms through which BA modulates LPS signalling in mononuclear cells. The effects of BA on signalling pathways downstream were focused on in this study.

EXPERIMENTAL APPROACH

We determined the ability of BA to interfere with p38 and extracellular regulated kinase (ERK) phosphorylation as well as Akt phosphorylation and nuclear factor-κB activation using LPS-activated hPBMCs as an in vitro model. LPS-induced endotoxin shock in mice was the in vivo model employed.

KEY RESULTS

BA inhibited LPS-induced COX-2 protein expression and prostaglandin E(2) production and also attenuated LPS-induced ERK and Akt phosphorylation, but not p38 in hPBMCs. BA abolished LPS-induced IκBα phosphorylation and thus normalized the levels of IκBα in cytosol. BA also inhibited LPS-induced reactive oxygen species formation and lactate dehydrogenase release. Interestingly, BA improved the life span of mice in endotoxin shock and also inhibited PGE(2) production and myeloperoxidase activity in vivo.

CONCLUSIONS AND IMPLICATIONS

BA modulates LPS-induced COX-2 expression in hPBMCs by inhibiting ERK and Akt pathways as well as by modulating IκBα phosphorylation. At the same time, no cell toxicity was observed. The effect of the drug was confirmed through in vivo experiments. The study gives an insight into the molecular mechanisms of BA.

Phenethyl isothiocyanate inhibits 12-O-tetradecanoylphorbol-13-acetate-induced inflammatory responses in mouse skin

Phenethyl isothiocyanate (PITC) is the hydrolysis product of the glucosinolate gluconasturtiin in cruciferous vegetables. This study was conducted to determine whether PITC inhibits 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation in the mouse ear. Topical application of 5 nmol of TPA to mouse ears markedly increased the ear weight, expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 protein, and phosphorylation of the inhibitor of κB (IκB) α, AKT, and extracellular signal-regulated protein kinase (ERK) 1/2 and reduced IκBα protein levels. Pretreatment with PITC (150-450 nmol) significantly suppressed these TPA-induced inflammatory responses. We also determined whether low concentrations of PITC (0.5-5 μmol/L) inhibited lipopolysaccharide (LPS)-stimulated inflammatory responses in Raw264.7 cells. PITC dose-dependently reduced the LPS-induced secretion of nitric oxide, prostaglandin E(2), interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, as well as COX-2 and iNOS protein expression. PITC also attenuated LPS-induced increases in iNOS, COX-2, IL- 6, IL-1β, and TNF-α mRNA levels, as well as the promoter-dependent transcriptional activation of the genes for iNOS and COX-2. PITC inhibited LPS-induced IκBα phosphorylation and degradation and subsequently reduced LPS-induced p65 nuclear translocation and the transcriptional activity of nuclear factor-κB (NF-κB), which was accompanied by a reduction in ERK1/2 and AKT phosphorylation. The results of this study demonstrated that PITC effectively inhibits inflammatory responses in vivo and in vitro, which may be mediated via the inhibition of AKT and ERK1/2 activation, leading to subsequent inhibition of the transcriptional activity of NF-κB.