The Small Glutathione Peroxidase Mimic 5P May Represent a New Strategy for the Treatment of Liver Cancer

Synthesis and glutathione peroxidase (GPx)-like activity of selenocystine (SeC) bioconjugates of biotin and lipoic acid

The conjugation of active biomolecules provides insight into their bioreactivity, leading to many applications in biotechnology and materials science. Herein, we report L-selenocystine (SeC) bioconjugates of lipoic acid (universal antioxidant) and biotin (Vitamin-H). The SeC-bioconjugates, SeC-Biotin (1) and SeC-Lipoic acid (2) were synthesized using solid phase peptide synthesis (SPPS) method and were characterized by multinuclear 1D (1H, 13C, 77Se) and 2D (1H-1H COSY and 1H-13C TOCSY) NMR spectroscopy, ESI-MS spectrometry, and RP-HPLC. The GPx-like enzyme mimicking activity of the SeC-bioconjugates 1 and 2 has been investigated through the coupled reductase assay method for the catalytic reductions of hydrogen peroxide into water. A significant enhancement in GPx-like enzymatic activity was observed for both novel bioconjugates SeC-Biotin (1) and SeC-Lipoic acid (2) as compared to diphenyl diselenide (Ph2Se2), L-selenocystine (SeC), biotin, lipoic acid, and ebselen.

Polyacylated Anthocyanins Derived from Red Radishes Protect Vascular Endothelial Cells Against Palmitic Acid-Induced Apoptosis via the p38 MAPK Pathway

Palmitic acid (PA), a widely consumed saturated fat, is known to induce the apoptosis of vascular endothelial cells. This study examined the protective effect of anthocyanin from red radish (ARR), which has been shown to protect the cardiovascular system and is rich in polyacylated pelargonidin (P) glycosides, on PA-treated SV 40 transfected aortic rat endothelial cells (SVAREC). In all, 22 distinct anthocyanins were identified in the ARR via ultra-high-performance liquid chromatography-triple quadrupole mass spectrometry, the most abundant of which were pelargonidin-3-(p-coumaroyl)diglucoside-5-glucoside (31.60%), pelargonidin-3-(feruloyl)diglucoside-5-(malonyl)glucoside (22.98%), pelargonidin-3-(p-coumaroyl)diglucoside-5-(malonyl)glucoside (8.02%), and pelargonidin-3-(feruloyl)diglucoside-5-glucoside (6.25%). P displayed the highest serum level (93.72%) in the ARR-treated mice, while polyacylated P glucosides were also absorbed intact. Furthermore, ARR treatment effectively increased cellular activity and reduced the ratio of Bcl-2-associated X protein : B cell lymphoma-2, while simultaneously alleviating the excessive production of reactive oxygen species in PA-treated SVAREC. Transcriptome and further verification analyses confirmed that the ARR-inhibiting PA-induced apoptosis of SVAREC was related to the p38 mitogen-activated protein kinase signaling pathway. Our results are the first to demonstrate that ARR may be a promising phytochemical in the prevention of PA-induced endothelial dysfunction.

Selenium nanoparticles overcomes sorafenib resistance in thioacetamide induced hepatocellular carcinoma in rats by modulation of mTOR, NF-κB pathways and LncRNA-AF085935/GPC3 axis

AIMS

The first-line treatment for advanced hepatocellular carcinoma (HCC) is the multikinase inhibitor sorafenib (SOR). Sofafenib resistance is linked to protein kinase B/ mammalian target of rapamycin (AKT/mTOR) and nuclear factor kappa B (NF-κB) activation, apoptosis inhibition and oxidative stress. This study investigated selenium nanoparticles (SeNps) to overcome SOR resistance in thioacetamide (TAA) induced HCC in rats.

MATERIALS AND METHODS

TAA (200 mg/kg/twice weekly, i.p.) was administered for 16 weeks to induce HCC.s. Rats were treated with oral SOR (10 mg/Kg daily), selenium, and SeNps (5 mg/kg three times/week) alone or in combination, for two weeks. Apoptosis, proliferation, angiogenesis, metastasis and drug resistance were assessed. Cleaved caspase 3 (C. CASP3), mTOR, and NF-κB were determined by western blotting. Expression of p53 gene and long-noncoding RNA-AF085935 was determined by qRT-PCR. Expression of B- Cell Leukemia/Lymphoma 2 (Bcl2), Bcl associated X protein (Bax)and glypican 3 (GPC3) was determined by enzyme-linked immunosorbent assay. Liver functions, antioxidant capacity, histopathology and CD34 immunohistochemistry were performed.

KEY FINDINGS

SOR/SeNps reversed TAA-induced HCC in rats, through reduction of oxidative stress, activation of p53, Bax and CASP3, and inhibition of Bcl2. SOR/SeNps ameliorated the HCC-induced effect on cell proliferation and drug resistance by targeting mTOR and NF-κB pathways. SOR/SeNps decreased CD34 immunostaining indicating a decrease in angiogenesis and metastasis. SOR/SeNps regulated HCC epigenetically through the lncRNA-AF085935/GPC3 axis.

SIGNIFICANCE

SOR/SeNps are a promising combination for tumor suppression and overcoming sorafenib resistance in HCC by modulating apoptosis, AKT/mTOR and NF-κB pathways, as well as CD34 and lncRNA-AF085935/GPC3 axis.

A novel therapeutic strategy for hepatocellular carcinoma: Immunomodulatory mechanisms of selenium and/or selenoproteins on a shift towards anti-cancer

Selenium (Se) is an essential trace chemical element that is widely distributed worldwide. Se exerts its immunomodulatory and nutritional activities in the human body in the form of selenoproteins. Se has increasingly appeared as a potential trace element associated with many human diseases, including hepatocellular carcinoma (HCC). Recently, increasing evidence has suggested that Se and selenoproteins exert their immunomodulatory effects on HCC by regulating the molecules of oxidative stress, inflammation, immune response, cell proliferation and growth, angiogenesis, signaling pathways, apoptosis, and other processes in vitro cell studies and in vivo animal studies. Se concentrations are generally low in tissues of patients with HCC, such as blood, serum, scalp hair, and toenail. However, Se concentrations were higher in HCC patient tissues after Se supplementation than before supplementation. This review summarizes the significant relationship between Se and HCC, and details the role of Se as a novel immunomodulatory or immunotherapeutic approach against HCC.