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| Silver NanoParticles (AgNPs) Summary: 1.Smaller sizes are generally more bioactive due to increased surface area and enhanced tumor accumulation via the enhanced permeability and retention (EPR) effect. 2.Two relevant forms: particulate silver (AgNPs) and ionic silver (Ag⁺). There is debate regarding oral use, as Ag⁺ can precipitate as AgCl in gastric acid, reducing bioavailability; AgNPs may partially avoid this via particulate uptake and intracellular Ag⁺ release. Gastric pH may influence this equilibrium. 3. Dose example 80kg person: 1.12-2mg/day, which can be calculated based on ppm and volume taken (see below) target < 10ppm and 120mL per day (30ppm and 1L per day caused argyria 30mg/day ) (Case Report: 9‐15 ppm@120mL, i.e. 1.1mg/L to 1.8mg/L per day) Likely 10ppm --> 10mg/L, hence if take 100mL, then 1mg/day? (for Cancer) The current Rfd for oral silver exposure is 5 ug/kg/d with a critical dose estimated at 14 ug/kg/d for the average person. Seems like the Cancer target range is 14ug/kg/day to 25ug/kg/day. 80Kg example: 1.12mg to 2mg “1.4µg/kg body weight. If I would have 70kg, I would want to use 100µg/day. However, for fighting active disease, I would tend to explore higher daily dose, as I think this may be too low.” These values reflect experimental or anecdotal contexts and are not established safe or therapeutic doses. 4. Antioxidants such as NAC can counteract AgNP cytotoxicity by restoring glutathione pools and suppressing ROS-mediated mitochondrial damage. 5. In vitro studies commonly show ROS elevation in both cancer and normal cells; however, in vivo, superior antioxidant, NRF2, and repair capacity in normal tissues may confer selectivity. 6. Pathways/mechanisms of action/: -” intracellular ROS was increased...reduction in levels of glutathione (GSH)” - Normal-cell selectivity is partly mediated by NRF2-dependent antioxidant and detoxification responses. - AgNPs impair mitochondrial electron transport, increasing electron leak and amplifying ROS upstream of ΔΨm collapse. -AgNPs inhibit VEGF-driven endothelial signaling and permeability (anti-angiogenic effect) -”upregulation of proapoptotic genes (p53, p21, Bax, and caspases) and downregulation of antiapoptotic genes (Bcl-2)” -” upregulation of AMPK and downregulation of mTOR, MMP-9, BCL-2, and α-SMA” -”p53 is a key player...proapoptotic genes p53 and Bax were significantly increased... noticeable reduction in Bcl-2 transcript levels” -” p53 participates directly in the intrinsic apoptosis pathway by regulating the mitochondrial outer membrane permeabilization” - “Proapoptotic markers (BAX/BCL-XL, cleaved poly(ADP-ribose) polymerase, p53, p21, and caspases 3, 8 and 9) increased.” -”The antiapoptotic markers, AKT and NF-kB, decreased in AgNP-treated cells.” Chronic accumulation and long-term systemic effects remain insufficiently characterized. Silver NanoParticles and Magnetic Fields Summary: 1. “exposure to PMF increased the ability of AgNPs uptake” 2. 6x improvement from AgNPs alone could glucose capping of SilverNPs work as trojan horse? Sodium selenite might protect against toxicity of AgNPs in normal cells. -uncoated AgNPs can degrade the gut microbiome. PVP, citrate, green-synthesized, chitosan coating, may reduce the effect. Similar oxidative considerations may apply to selenium compounds, though mechanisms differ. co-ingestion with food (higher pH) favors reduction and lower Ag+ levels. -action mechanisms of AgNPs: the release of silver ions (Ag+), generation of reactive oxygen species (ROS), destruction of membrane structure. AgNP anticancer effects come from three overlapping mechanisms: -Nanoparticle–cell interaction (uptake, membrane effects) -Intracellular ROS generation -Controlled Ag⁺ release inside cancer cells Comparison adding Citrate Capping | Property | Uncapped AgNPs | Citrate-capped AgNPs | | --------------------- | -------------- | -------------------- | | Stability | Poor | Excellent | | Free Ag⁺ | High | Low | | Normal cell toxicity | Higher | Lower | | Cancer selectivity | Lower | **Higher** | | Mechanism specificity | Crude | **Targeted** | | Storage behavior | Degrades | Stable |
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| Selenoproteins are a group of proteins that incorporate the rare amino acid selenocysteine into their structure. Selenocysteine, sometimes called the “21st amino acid,” is encoded by the UGA codon in a unique context that requires specific translational machinery. Many selenoproteins are known for their antioxidant and redox-regulatory functions, which are critical in maintaining cellular homeostasis. These functions help protect cells from oxidative stress and damage—processes that, when dysregulated, can contribute to carcinogenesis. Roles of Selenoproteins in Cancer. 1. Antioxidant Defense & Redox Regulation -Glutathione Peroxidases (GPxs): Enzymes like GPX1, GPX2, and GPX3 reduce hydrogen peroxide and lipid hydroperoxides. This protects cells against oxidative DNA damage. -Thioredoxin Reductases (TXNRDs): TXNRD1, TXNRD2, and TXNRD3 help maintain the reduced state of thioredoxin, thereby contributing to redox homeostasis and cell survival under stress. 2. Cellular Proliferation and Apoptosis -Selenoproteins may modulate signaling pathways that regulate cell cycle progression and apoptosis. Variations in expression levels—either upregulation or downregulation—can tip the balance toward uncontrolled cell growth or cell death. The expression of selenoproteins in cancers is complex and can vary by tumor type. Here are some examples: Glutathione Peroxidases (GPxs) -GPX1: Both overexpression and underexpression have been reported depending on the tumor context. In some cases, high GPX1 expression can help cancer cells survive oxidative stress. -GPX2: Often upregulated in colorectal cancer and some GC, poor prognosis. -GPX3: Typically downregulated in many cancers with tumor progression and poor outcome, suggesting its role as a tumor suppressor. Thioredoxin Reductases (TXNRDs) -TXNRD1: Frequently overexpressed in various tumors such as lung, breast, and liver cancers. High TXNRD1 levels are generally associated with a poor prognosis. -SELENOP (Selenoprotein P) SELENOP serves as a selenium transport protein and has antioxidant properties. Decreased SELENOP expression has been linked to poorer outcomes in some cancers, possibly due to reduced selenium availability for other protective selenoproteins. Other Selenoproteins -SELENOF and SELENOS: -SELENOM and SELENOK: |
| 1908- | AgNPs, | Exposure to Silver Nanoparticles Inhibits Selenoprotein Synthesis and the Activity of Thioredoxin Reductase |
| - | in-vitro, | Lung, | A549 |
Query results interpretion may depend on "conditions" listed in the research papers. Such Conditions may include : -low or high Dose -format for product, such as nano of lipid formations -different cell line effects -synergies with other products -if effect was for normal or cancerous cells
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