Induction of Apoptosis by Gluconasturtiin-Isothiocyanate (GNST-ITC) in Human Hepatocarcinoma HepG2 Cells and Human Breast Adenocarcinoma MCF-7 Cells

Quantification and Diversity Analyses of Major Glucosinolates in Conserved Chinese Cabbage (Brassica rapa L. ssp. pekinensis) Germplasms

The genebank at the National Agrobiodiversity Center (RDA-Genebank, Jeonju, Republic of Korea), conserves approximately 8000 germplasms of Brassica spp., of which Chinese cabbage (Brassica rapa L. ssp. pekinensis) is one of the major crops actively used as food in Northeast Asia, including Korea, as the main ingredient for kimchi. Glucosinolates are a major class of compounds in Chinese cabbage that are responsible for their distinctive flavor, and RDA-Genebank is constantly building a related database (DB) to select suitable germplasms required by consumers and provide resources for breeding programs. In this study, ten glucosinolates were analyzed in sixty Chinese cabbage germplasms. Six aliphatic glucosinolates were the major components, accounting for 85.00% to 91.98% of total glucosinolates in each germplasm. Among them, gluconapin (333.26 to 23,501.58 μmol∙kg−1 DW) was highly represented, followed by glucobrassicanapin (545.60 to 10,344.70 μmol∙kg−1 DW) and progoitrin (155.28 to 8536.51 μmol∙kg−1 DW). In addition, we selected germplasms with a high content of each studied glucosinolate. To analyze the diversity and distribution of glucosinolates among the studied germplasms, Pearson’s correlation was performed, and the related results were interpreted through their biosynthetic pathways. The k-means clustering indicated four optimal clusters, which were confirmed through principal component analysis. Orthogonal projection to latent structure discriminant analysis (OPLS-DA) was also performed on the status (landrace and cultivar) and origin (Korea, China, Taiwan, and Japan) passport data of the germplasms, followed by the calculation of variable importance in the projection (VIP) values. These results are part of a continuous series of studies to analyze the glucosinolates of Brassica germplasms that are being conserved at RDA-Genebank. We aim to provide related results through a public platform accessible to everyone and thereby improve the distribution of Brassica germplasms.

Moringa oleifera leaf extract induces osteogenic-like differentiation of human osteosarcoma SaOS2 cells

Introduction

Moringa oleifera is known as a ‘natural nutrition of the tropics’ because it provides vital nutritional supplements and a variety of pharmacological benefits. The focus of this study was to elucidate the dose dependent effects of Moringa oleifera leaf (MOL) extract on the growth of the human osteoblast-like osteosarcoma SaOS-2 cell line and primary osteoblast cells.

Methods

Trypan blue & tetrazolium assay, intracellular ROS generation, chromatin condensation, cell cycle analysis, alkaline phosphatase (ALP), mineralization, and osteogenic gene expression were tested on both treated and untreated osteosarcoma SaOS-2 cells.

Results

As revealed by cell viability assay, growth activity was observed at concentrations 25 and 50 μg/mL of MOL extract, whereas 100 and 200 μg/mL doses decreased the proliferation activity, resulting in ROS production and chromatin condensation. Cell cycle study revealed that MOL extract at 50 and 100 μg/mL concentrations arrested the cells in the G2/M phase. Low doses increased the ALP levels, mineralization, and expression of the bone morphogenetic protein 2 (BMP2) and runt-related transcription factor 2 (Runx2) genes in osteoblast-like SaOS-2 cells, however, high doses inhibited the proliferation properties of MOL extract. Through AutoDock Vina and iGEMDOCK 2.1, the interaction of active components of MOL, such as β-sitosterol, quercetin and kaempferol, with BMP2 and Runx2 proteins revealed a reasonable binding affinity. Moreover, these components did not show any Lipinski's rule of five violation and showed predictable pharmacokinetic properties.

Conclusion

The results of the biphasic dose-response of MOL extract on the growth activity of osteoblast-like SaOS-2 cells and in silico binding interface, may provide a therapeutic and/or preventive implication in prospective drug development.

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Low doses of Moringa oleifera leaf (MOL) extract increased the cell viability of SaOS-2 cells and primary osteoblasts.

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High doses decreased the growth, resulting in ROS production and chromatin condensation and cell cycle arrest.

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Small doses increased the ALP levels, mineralization, and BMP2 and Runx2 genes expression, and vice versa.

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In silico analysis showed good binding interaction of active components of MOL with BMP2 and Runx2 proteins.

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The biphasic dose-response of MOL and in silico analysis may provide an implication for prospective drug development.

The recent advances of glucosinolates and their metabolites: Metabolism, physiological functions and potential application strategies

Glucosinolates and their metabolites from Brassicaceae plants have received widespread attention due to their anti-inflammatory effects. Glucosinolates occurs an "enterohepatic circulation" in the body, and the glucosinolates metabolism mainly happens in the intestine. Glucosinolates can be converted into isothiocyanates by intestinal bacteria, which are active substances with remarkable anti-inflammatory, anti-cancer, anti-obesity and neuroprotective properties. This biotransformation can greatly improve the bioactivities of glucosinolates. However, multiple factors in the environment can affect the biotransformation to isothiocyanates, including acidic pH, ferrous ions and thiocyanate-forming protein. The derivatives of glucosinolates under those conditions are usually nitriles and thiocyanates, which may impair the potential health benefits. In addition, isothiocyanates are extremely unstable because of an active sulfhydryl group, which limits their applications. This review mainly summarizes the classification, synthesis, absorption, metabolism, physiological functions and potential application strategies of glucosinolates and their metabolites.

Microbial transglutaminase nanoflowers as an alternative nanomedicine for breast cancer theranostics

Breast cancer is the most common malignancy among women. With the aim of decreasing the toxicity of conventional breast cancer treatments, an alternative that could provide appropriate and effective drug utilization was envisioned. Thus, we contemplated and compared the in vitro effects of microbial transglutaminase nanoflowers (MTGase NFs) on breast cancer cells (MCF-7). Transglutaminase is an important regulatory enzyme acting as a site-specific cross-linker for proteins. With the versatility of MTGase facilitating the nanoflower formation by acting as molecular glue, it was demonstrated to have anti-cancer properties. The rational drug design based on a transglutaminase enzyme-assisted approach led to the uniform shape of petals in these nanoflowers, which had the capacity to act directly as an anti-cancer drug. Herein, we report the anti-cancer characteristics portrayed by enzymatic MTGase NFs, which are biocompatible in nature. This study demonstrated the prognostic and therapeutic significance of MTGase NFs as a nano-drug in breast cancer treatment. The results on MCF-7 cells showed a significantly improved in vitro therapeutic efficacy. MTGase NFs were able to exhibit inhibitory effects on cell viability (IC₅₀-8.23 μg ml⁻¹) within 24 h of dosage. To further substantiate its superior anti-proliferative role, the clonogenic potential was measured to be 62.8%, along with migratory inhibition of cells (3.76-fold change). Drastic perturbations were induced (4.61-fold increase in G0/G1 phase arrest), pointed towards apoptotic induction with a 58.9% effect. These results validated the role of MTGase NFs possessing a cytotoxic nature in mitigating breast cancer. Thus, MTGase bestows distinct functionality towards therapeutic nano-modality, i.e., nanoflowers, which shows promise in cancer treatment.

Development of a novel therapeutic nano-modality in the form of enzymatic transglutaminase nanoflowers; endowed with anti-cancerous action against breast cancers.

The degradation kinetics and mechanism of moringin in aqueous solution and the cytotoxicity of degraded products

In this work, we investigated the degradation of moringin (4-[(α-l-rhamnosyloxy)benzyl]-isothiocyanate), a major bioactive isothiocyanate (ITC) found in moringa seeds (Moringa oleifera Lam), at various food processing conditions. Moringin degrades rapidly to several water-soluble products via a pseudo-first-order kinetics. By analyzing the reaction products, the degradation mechanism was found to be through hydrolyzing to (A) 1-O-(4-hydroxymethylphenyl) α-l-rhamnopyranoside (rhamnobenzyl alcohol RBA) or (B) rhamnobenzylamine. The formed amine further reacts with moringin to form N,N'-bis{4-[(α-l-rhamnosyloxy)benzyl]}thiourea (di-rhamnobenzyl thiourea, DRBTU). In addition, moringin isomerizes to 4-[(α-l-rhamnosyloxy)benzyl]thiocyanate (RBTC), which further reacts with moringin to form S,N-bis{4-[(α-l-rhamnosyloxy)benzyl]}-dithiocarbamate (DRBDTC). Furthermore, pH was found to have an effect on the degradation of moringin. RBA and RBTC were major degraded products in neutral and acidic conditions while thiourea (DRBTU) was in alkaline condition. Although moringin showed higher cytotoxicity to cancer cells, its degraded products showed very weak or no activities, suggesting that the isothiocyanate group of ITCs is essential for their cancer chemoprevention activities.

Dietary isothiocyanates inhibit cancer progression by modulation of epigenome

Cell cycle, growth, survival and metabolism are tightly regulated together and failure in cellular regulation leads to carcinogenesis. Several signaling pathways like the PI3K, WNT, MAPK and NFKb pathway exhibit aberrations in cancer and help achieve hallmark capabilities. Clinical research and in vitro studies have highlighted the role of epigenetic alterations in cancer onset and development. Altered gene expression patterns enabled by changes in DNA methylation, histone modifications and RNA processing have proven roles in cancer hallmark acquisition. The reversible nature of epigenetic processes offers robust therapeutic targets. Dietary bioactive compounds offer a vast compendium of effective therapeutic moieties. Isothiocyanates (ITCs) sourced from cruciferous vegetables demonstrate anti-proliferative, pro-apoptotic, anti-inflammatory, anti-migratory and anti-angiogenic effect against several cancers. ITCs also modulate the redox environment, modulate signaling pathways including PI3K, MAPK, WNT, and NFkB. They also modulate the epigenetic machinery by regulating the expression and activity of DNA methyltransferases, histone modifiers and miRNA. This further enhances their transcriptional modulation of key cellular regulators. In this review, we comprehensively assess the impact of ITCs such as sulforaphane, phenethyl isothiocyanate, benzyl isothiocyanate and allyl isothiocyanate on cancer and document their effect on various molecular targets. Overall, this will facilitate consolidation of the current understanding of the anti-cancer and epigenetic modulatory potential of these compounds and recognize the gaps in literature. Further, we discuss avenues of future research to develop these compounds as potential therapeutic entities.