Development of Moringa oleifera as functional food targeting NRF2 signaling: antioxidant and anti-inflammatory activity in experimental model systems

Pharmacological activation of nuclear factor erythroid 2 related factor 2 (NRF2) provides protection against several environmental diseases by inhibiting oxidative and inflammatory injury. Besides high in protein and minerals, Moringa oleifera leaves contain several bioactive compounds, predominantly isothiocyanate moringin and polyphenols, which are potent inducers of NRF2. Hence, M. oleifera leaves represent a valuable food source that could be developed as a functional food for targeting NRF2 signaling. In the current study, we have developed a palatable M. oleifera leaf preparation (henceforth referred as ME-D) that showed reproducibly a high potential to activate NRF2. Treatment of BEAS-2B cells with ME-D significantly increased NRF2-regulated antioxidant genes (NQO1, HMOX1) and total GSH levels. In the presence of brusatol (a NRF2 inhibitor), ME-D-induced increase in NQO1 expression was significantly diminished. Pre-treatment of cells with ME-D mitigated reactive oxygen species, lipid peroxidation and cytotoxicity induced by pro-oxidants. Furthermore, ME-D pre-treatment markedly inhibited nitric oxide production, secretory IL-6 and TNF-α levels, and transcriptional expression of Nos2, Il-6, and Tnf-α in macrophages exposed to lipopolysaccharide. Biochemical profiling by LC-HRMS revealed glucomoringin, moringin, and several polyphenols in ME-D. Oral administration of ME-D significantly increased NRF2-regulated antioxidant genes in the small intestine, liver, and lungs. Lastly, prophylactic administration of ME-D significantly mitigated lung inflammation in mice exposed to particulate matter for 3-days or 3-months. In conclusion, we have developed a pharmacologically active standardized palatable preparation of M. oleifera leaves as a functional food to activate NRF2 signaling, which can be consumed as a beverage (hot soup) or freeze-dried powder for reducing the risk from environmental respiratory disease.

A Recent Update on the Epigenetic Repertoire and Chromatin Modifying Therapy in Diabetes Mellitus: A Comprehensive Review

Several epigenome studies reported the ability of genes to modulate the lipogenic and glucogenic pathways during insulin signaling as well as the other pathways involved in cardiometabolic diseases. Epigenetic plasticity and oxidative stress are interrelated in the pathophysiology of insulin resistance (IR) and cardiometabolic disease conditions. This review aims to ascertain the previous research evidence pertaining to the role of the epigenome and the variations of histone and non-histone proteins during cardiometabolic disease conditions and insulin signaling to develop effective disease-based epigenetic biomarkers and epigenetics-based chromatic therapy. Several public databases, including PubMed, National Library of Medicine, Medline, and google scholar, were searched for the peer-reviewed and published reports. This study delineates the consistent body of evidence regarding the epigenetic alterations of DNA/histone complexes pertinent to oxidative stress, insulin signaling, metabolic cardiomyopathy, and endothelial dysfunction in patients with cardiometabolic diseases. It has been described that both DNA methylation and post-translational histone alterations across visceral and subcutaneous adipose tissue could facilitate gene transcription to modulate inflammation, lipogenesis, and adipogenesis as the complex network of chromatin-modifying enzymatic proteins involved in the defensive insulin signaling across vasculature in patients with cardiometabolic diseases. Resveratrol, vorinostat, trichostatin, and apabetalone are reported to have significant implications as epigenetic modulators. Based on the epigenetic alterations, a wide range of protein/gene markers, such as interleukin-4 (IL-4) and interferon-γ (IFNγ) genes, may be considered as biomarkers in these patients due to their ability to the polarization of immune cells involved in tissue inflammation and atherosclerosis. Hence, it is crucial to unravel the cell-specific epigenetic information to develop individual risk assessment strategies for chromatin-modifying therapies in patients with cardiometabolic diseases.

Phytochemical-rich Fractions from Foxtail Millet (Setaria italica (L.) P.Beauv) Seeds Exhibited Antioxidant Activity and Reduced the Viability of Breast Cancer Cells In Vitro by Inducing DNA Fragmentation and Promoting Cell Cycle Arrest

BACKGROUND

The demand for millet-based diets has increased significantly in recent years due to their beneficial effects on human health. Foxtail Millet (Setaria italica (L.) P.Beauv, previously known as Panicum italicum L., referred as FTM in this manuscript) seeds have been not only used as astringent and diuretic agents, but they are also used to treat dyspepsia and rheumatism. Recent studies have shown that solvent extracts from FTM seeds exhibited antioxidant and antiinflammatory activities. However, the nature and antiproliferative potential of phytochemical constituents of solvent extracts are not much explored.

OBJECTIVES

Major objectives of this study are to generate and characterize the phytochemical-rich fractions from Foxtail millet seeds, test the antioxidant activity and antiproliferative potential against cell lines representing carcinomas of the breast, and determine the mechanism(s) of cell growth inhibition.

METHODS

Phytochemical-rich fractions were generated by extracting the seeds using 70% ethanol (FTM-FP) and 10% alkali (FTM-BP). Antioxidant potential was determined by ferric reducing antioxidant power (FRAP) assay and DPPH radical scavenging activity assays. The antiproliferative potential was determined using sulforhodamine-B assay. The impact on cell cycle and DNA fragmentation was analyzed by staining the cells with DAPI followed by analyzing the stained cells using NC-3000.

RESULTS

Analysis of the results showed the presence of phenolics and flavonoids in the FTM-FP and FTM-BP fractions. Both fractions exhibited antiproliferative potential against breast cancer cell lines. Mechanistically, both fractions induced G2/M cell cycle arrest and increased the fragmentation of DNA, which lead to the accumulation of cells in the Sub-G1 phase.

CONCLUSION

In summary, results of this study demonstrated the potential of foxtail millet phytochemical fractions for retarding the proliferative potential of breast cancer cells.

Design, Synthesis, Characterization, and Crystal Structure Studies of Nrf2 Modulators for Inhibiting Cancer Cell Growth In Vitro and In Vivo

Nrf2 is one of the important therapeutic targets studied extensively in several cancers including the carcinomas of the colon and rectum. However, to date, not many Nrf2 inhibitors showed promising results for retarding the growth of colorectal cancers (CRCs). Therefore, in this study, first, we have demonstrated the therapeutic effect of siRNA-mediated downmodulation of Nrf2 on the proliferation rate of CRC cell lines. Next, we have designed, synthesized, characterized, and determined the crystal structures for a series of tetrahydrocarbazoles (THCs) and assessed their potential to modulate the activity of Nrf2 target gene NAD(P)H:quinone oxidoreductase (NQO1) activity by treating colorectal carcinoma cell line HCT-116. Later, the cytotoxic potential of compounds was assessed against cell lines expressing varying amounts of Nrf2, viz., breast cancer cell lines MDA-MB-231 and T47D (low functionally active Nrf2), HCT-116 (moderately active Nrf2), and lung cancer cell line A549 (highly active Nrf2), and the lead compound 5b was tested for its effect on cell cycle progression in vitro and for retarding the growth of Ehrlich ascites carcinomas (EACs) in mice. Data from our study demonstrated that among various compounds 5b exhibited better therapeutic index and retarded the growth of EAC cells in mice. Therefore, compound 5b is recommended for further development to target cancers.