Identification and biotin receptor-mediated activity of a novel seleno-biotin compound that inhibits viability of and induces apoptosis in ovarian cancer cells.

A series of seleno-biotin analogs were synthesized and their anticancer activity and mode of action were assessed using ovarian cancer cells. Compound 2, out of the other analogs, in direct comparison to biotin alone, more effectively reduced the cell viability and induced apoptosis in ovarian cancer cell lines in a dose dependent manner as demonstrated by the cell viability assay, trypan blue dye exclusion assay, Annexin V/7-AAD, and Caspase 3/7 apoptosis assays. Furthermore, compound 2 showed efficacy better than 5-fluorouracil (5-FU) and similar to cisplatin, in vitro; notably it was more cytotoxic to drug-resistant Hey A8 cells than cisplatin.

Selenofolate inhibits the proliferation of IGROV1 cancer cells independently from folate receptor alpha.

Cancer is one of the main causes of human mortality worldwide and novel chemotherapeutics are required due to the limitations of conventional cancer therapies. For example, using redox selenium compounds as novel chemotherapeutics seem to be very promising. The objective of this study was to explore if folate could be used as a carrier to deliver a newly synthesised selenium derivative selenofolate into cancer cells.

In Vitro Cytotoxicity of Trastuzumab (Tz) and Se-Trastuzumab (Se-Tz) against the Her/2 Breast Cancer Cell Lines JIMT-1 and BT-474.

Her/2+ breast cancer accounts for ~25% mortality in women and overexpression of Her/2 leads to cell growth and tumor progression. Trastuzumab (Tz) with Taxane is the preferred treatment for Her/2+ patients. However, Tz responsive patients often develop resistance to Tz treatment.

Investigating the Potential of Conjugated Selenium Redox Folic Acid as a Treatment for Triple Negative Breast Cancer.

Previous studies have demonstrated that redox selenium compounds arrest cancer cell viability in vitro through their pro-oxidative activity by generating superoxide (O•). Currently, there are no efficacious treatment options for women with Triple Negative Breast Cancer (TNBC). However, the association between the over-expression of the Folate Receptor Alpha (FRA) in TNBC and other cancer cells, has led to the possibility that TNBCs might be treated by targeting the FRA with redox selenium covalent Folic Acid conjugates.

Selenomethionine and Methioninase: Selenium Free Radical Anticancer Activity.

Colloidal selenium, was first used to treat cancer as early as 1911 in both humans and mice. Selenium was identified as the toxic component in forage plants of sheep, cattle, and horses in the 1930s. The animal toxicity of selenium compounds was determined to be from the metabolism by animals of the elevated concentrations of Se-methylselenocysteine and selenomethionine in plants.

Cytotoxicity of Selenium Immunoconjugates against Triple Negative Breast Cancer Cells.

Within the subtypes of breast cancer, those identified as triple negative for expression of estrogen receptor α (ESR1), progesterone receptor (PR) and human epidermal growth factor 2 (HER2), account for 10⁻20% of breast cancers, yet result in 30% of global breast cancer-associated deaths. Thus, it is critical to develop more targeted and efficacious therapies that also demonstrate less side effects. Selenium, an essential dietary supplement, is incorporated as selenocysteine (Sec) in vivo into human selenoproteins, some of which exist as anti-oxidant enzymes and are of importance to human health.

Selenium-mediated arsenic excretion in mammals: a synchrotron-based study of whole-body distribution and tissue-specific chemistry.

Arsenicosis, a syndrome caused by ingestion of arsenic contaminated drinking water, currently affects millions of people in South-East Asia and elsewhere. Previous animal studies revealed that the toxicity of arsenite essentially can be abolished if selenium is co-administered as selenite. Although subsequent studies have provided some insight into the biomolecular basis of this striking antagonism, many details of the biochemical pathways that ultimately result in the detoxification and excretion of arsenic using selenium supplements have yet to be thoroughly studied.

25 hydroxy vitamin D is higher when a renal multivitamin is given with cholecalciferol at hemodialysis.

Background And Objectives: Seventy six hemodialysis (HD) patients were used in a prospective randomized and clinical trial to determine if a multivitamin with vitamin D (cholecalciferol 12,000 IU/week) given during dialysis would improve the vitamin D status of hemodialysis subjects.

Methods And Study Design: Subjects were randomly assigned to two groups: 37 subjects were in the renal multivitamin without vitamin D (MV) group and 39 subjects were in a multivitamin route with vitamin D (MVD) group (12,000 IU of cholecalciferol per week). All subjects were given 2 multivitamin tablets at their 3 HD sessions each week for 20 weeks.

Observation of the seleno bis-(S-glutathionyl) arsinium anion in rat bile.

Certain arsenic and selenium compounds show a remarkable mutual cancelation of toxicities, where a lethal dose of one can be voided by an equimolar and otherwise lethal dose of the other. It is now well established that the molecular basis of this antagonism is the formation and biliary excretion of seleno bis-(S-glutathionyl) arsinium anion [(GS)2AsSe](-). Previous work has definitively demonstrated the presence of [(GS)2AsSe](-) in rabbit bile, but only in the presence of other arsenic and selenium species.

Design, Synthesis, and Biological Evaluation of Novel Selenium (Se-NSAID) Molecules as Anticancer Agents.

The synthesis and anticancer evaluation of novel selenium-nonsteroidal anti-inflammatory drug (Se-NSAID) hybrid molecules are reported. The Se-aspirin analogue 8 was identified as the most effective agent in reducing the viability of different cancer cell lines, particularly colorectal cancer (CRC) cells, was more selective toward cancer cells than normal cells, and was >10 times more potent than 5-FU, the current therapy for CRC. Compound 8 inhibits CRC growth via the inhibition of the cell cycle in G1 and G2/M phases and reduces the cell cycle markers like cyclin E1 and B1 in a dose dependent manner; the inhibition of the cell cycle may be dependent on the ability of 8 to induce p21 expression.

Low Starch/Low Dairy Diet Results in Successful Treatment of Obesity and Co-Morbidities Linked to Polycystic Ovary Syndrome (PCOS).

Background: Polycystic Ovary Syndrome (PCOS) affects approximately 15% of reproductive-age women and increases risk of insulin resistance, type 2 diabetes mellitus, cardiovascular disease, cancer and infertility. Hyperinsulinemia is believed to contribute to or worsen all of these conditions, and increases androgens in women with PCOS. Carbohydrates are the main stimulators of insulin release, but research shows that dairy products and starches elicit greater postprandial insulin secretion than non-starchy vegetables and fruits.

Redox-active selenium compounds--from toxicity and cell death to cancer treatment.

Selenium is generally known as an antioxidant due to its presence in selenoproteins as selenocysteine, but it is also toxic. The toxic effects of selenium are, however, strictly concentration and chemical species dependent. One class of selenium compounds is a potent inhibitor of cell growth with remarkable tumor specificity.

Effect of a low-starch/low-dairy diet on fat oxidation in overweight and obese women with polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) affects between 4%-18% of reproductive-aged women and is associated with increased risk of obesity and obesity-related disease. PCOS is associated with hyperinsulinemia, which is known to impair fat oxidation. Research shows that carbohydrates from dairy and starch-based foods cause greater postprandial insulin secretion than carbohydrates from nonstarchy vegetables and fruits.

Phenylalkyl isoselenocyanates vs phenylalkyl isothiocyanates: thiol reactivity and its implications.

Phenylalkyl isoselenocyanate (ISC) compounds were recently designed in our laboratory by incorporating the anticancer element selenium into a panel of phenylalkyl isothiocyanates (ITCs), known to have anticancer properties. A structural activity investigation was carried out to compare the ISC and ITC panels. Cell viability assay and Annexin V staining for apoptosis showed ISC compounds to be more potent in killing A549 lung adenocarcinoma cells.

Low-level groundwater arsenic exposure impacts cognition: a project FRONTIER study.

Arsenic is a ubiquitous environmental toxin with known neurological consequences. Few studies, however, have investigated groundwater arsenic concentrations and cognition among adults and elders. In the study described in this article, the authors examined the potential link between cognitive functioning and low concentrations of arsenic in drinking water.

Antioxidant-prooxidant properties of a new organoselenium compound library.

The present study describes the biological evaluation of a library of 59 organo-selenium compounds as superoxide (O₂⁻) generators and cytotoxic agents in human prostate cancer cells (PC-3) and in breast adenocarcinoma (MCF-7). In order to corroborate that the biological activity for selenium compounds depends on the chemical form, a broad structural variety is presented. These structures include selenocyanates, diselenides, selenoalkyl functional moieties and eight newly synthesized symmetrically substituted dithioselenites and selenylureas.

Organoselenium coating on cellulose inhibits the formation of biofilms by Pseudomonas aeruginosa and Staphylococcus aureus.

Among the most difficult bacterial infections encountered in treating patients are wound infections, which may occur in burn victims, patients with traumatic wounds, necrotic lesions in people with diabetes, and patients with surgical wounds. Within a wound, infecting bacteria frequently develop biofilms. Many current wound dressings are impregnated with antimicrobial agents, such as silver or antibiotics.

Selenium-enriched garlic and cabbage as a dietary selenium source for broilers.

This study determined the selenium (Se) bioavailability from Se-enriched garlic and cabbage using broiler chickens. Se-enriched garlic (18.5 mg of Se/kg) and cabbage (101.

Oxidation of glutathione and superoxide generation by inorganic and organic selenium compounds.

The carcinostatic activities of selenium (Se) compounds have been shown to be composition and concentration dependent. Several studies have indicated that the ratios between glutathione (GSH) and Se may play an important role in Se catalysis and toxicity. The present study examined the catalytic effect of three selenium compounds on GSH oxidation using lucigenin-dependent chemiluminescence (CL) as an indirect measure of superoxide generation.

Cancer chemoprevention: a radical perspective.

Cancer chemopreventive agents block the transformation of normal cells and/or suppress the promotion of premalignant cells to malignant cells. Certain agents may achieve these objectives by modulating xenobiotic biotransformation, protecting cellular elements from oxidative damage, or promoting a more differentiated phenotype in target cells. Conversely, various cancer chemopreventive agents can encourage apoptosis in premalignant and malignant cells in vivo and/or in vitro, which is conceivably another anticancer mechanism.

Toxicity and mutagenicity of selenium compounds in Saccharomyces cerevisiae.

Selenium (Se) is an essential trace element for humans, animals and some bacteria which is important for many cellular processes. Se's bio-activity is mainly influenced by its chemical form and dose. The use of Se supplements in the human diet emphasizes the need to establish both the beneficial and detrimental doses of each Se compound.

Efficacy of dietary selenium sources on growth and carcass characteristics of growing-finishing pigs fed diets containing high endogenous selenium.

A study was conducted to determine the efficacy of organic (Se-yeast, SelenoSource AF, Diamond V Mills Inc., Cedar Rapids, IA) and inorganic sources of Se on growth performance, tissue Se accretion, and carcass characteristics of growing-finishing pigs fed diets with high endogenous Se content. A total of 180 pigs at 34.

Prevention of bacterial colonization of contact lenses with covalently attached selenium and effects on the rabbit cornea.

Purpose: Although silicone hydrogel materials have produced many corneal health benefits to patients wearing contact lenses, bacteria that cause acute red eye or corneal ulcers are still a concern. A coating that inhibits bacterial colonization while not adversely affecting the cornea should improve the safety of contact lens wear. A covalent selenium (Se) coating on contact lenses was evaluated for safety using rabbits and prevention of bacterial colonization of the contact lenses in vitro.

Arsenic and selenium in human hair: a comparison of five countries with and without arsenicosis.

The selenium (Se) content of the diet and/or selenium supplements might have an ameliorating effect on arsenic (As) toxicity as recently shown by Wang et al., Yang et al., and as reviewed by Spallholz et al.

Metabolism of selenomethionine by rainbow trout (Oncorhynchus mykiss) embryos can generate oxidative stress.

Although selenium is required by vertebrates, toxicity can arise at concentrations only slightly greater than those they require. The toxicity of Se is thought to arise from its ability to substitute for sulfur during the assembly of proteins. However, recent studies also indicate that some forms of selenium are capable of generating oxidative stress in an in vitro test system that includes glutathione.