ARGIMAN TABLETS
L-arginine/Co-enzyme Q-10/Vitamin E-acetate/Policosanol/Zinc sulfate monohydrate/Lycopene /black pepper extract/elemental selenium
What it does
Black is an ingredient used in various medicinal products.
Read more in plain English ↓Plain-language summary for general understanding - not medical advice. Always follow your pharmacist/doctor.
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Sourcing - Kenya onlyRegistration & product details
Source: Food and Drugs Authority · fetched 2026-04-18 08:37:08 · updated 2026-09-29 04:00:10
About black
Black is an ingredient used in various medicinal products.
How it works
The specific mechanism of action for black is not provided.
Who it's for
Black may be suitable for different patient groups, depending on its applications.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About elemental
Elemental is a type of supplement that provides essential nutrients in their simplest form, helping to improve nutrition and support overall health.
What it treats
- nutritional support
- malnutrition
- deficiencies in essential nutrients
How it works
Elemental supplements provide the body with necessary nutrients that may be lacking in the diet, helping to improve health and energy levels.
Who it's for
This supplement is suitable for individuals who need extra nutritional support, such as those recovering from illness or those with specific dietary needs.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About extract
This medicine is an extract that is used for various health conditions.
What it treats
- general health improvement
- nutritional support
How it works
The extract may provide health benefits by supplying essential nutrients or compounds that support bodily functions.
Who it's for
This medicine is suitable for individuals looking to improve their overall health or address specific nutritional needs.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About l-arginine
L-arginine is an amino acid that helps improve blood flow and may support heart health.
What it treats
- angina (chest pain)
- heart disease
- erectile dysfunction
- high blood pressure (hypertension)
- wound healing
How it works
L-arginine helps the body produce nitric oxide, which relaxes blood vessels and improves blood circulation.
Who it's for
L-arginine may be suitable for adults looking to improve their cardiovascular health or manage related conditions.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About lycopene
Lycopene is a natural pigment found in tomatoes and other red fruits and vegetables. It is known for its antioxidant properties.
What it treats
- prostate cancer
- breast cancer
- heart disease
- high cholesterol
How it works
Lycopene helps protect cells from damage caused by free radicals, which can contribute to various diseases.
Who it's for
Adults looking for potential health benefits related to cancer and heart health.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About pepper
Pepper is a spice commonly used to add flavor to food. It may also have some health benefits.
What it treats
- enhances flavor in cooking
- may aid digestion
- potential antioxidant properties
How it works
Pepper contains compounds that can stimulate digestion and may have beneficial effects on health.
Who it's for
Adults looking to enhance their meals or support digestion.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About policosanol
Policosanol is a natural supplement that may help lower cholesterol levels in the blood.
What it treats
- high cholesterol (hyperlipidemia)
- heart disease prevention
How it works
Policosanol works by reducing the production of cholesterol in the liver and helping to remove it from the bloodstream.
Who it's for
Adults looking to manage cholesterol levels and support heart health.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About selenium
Selenium is a mineral that is important for various bodily functions, including supporting the immune system and maintaining healthy cells.
What it treats
- supports immune health
- promotes healthy cell function
- may help prevent certain diseases
How it works
Selenium acts as an antioxidant, helping to protect cells from damage caused by free radicals.
Who it's for
Selenium is for people who need support for their immune system or those who have low levels of this mineral.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
About tocopherol
Tocopherol is a form of vitamin E, an antioxidant that helps protect cells from damage.
What it treats
- skin health
- antioxidant support
- nutritional supplement
How it works
It helps protect your body from harmful substances by neutralizing free radicals.
Who it's for
It is suitable for people looking to support their overall health and skin condition.
AI-assisted summary grounded in BNF data - general information only, not medical advice. Always confirm with your pharmacist or doctor.
Clinical monograph: Selenium
BNF-referencedSelenium is a trace element essential for human health, playing a crucial role in various biological processes. It is primarily incorporated into selenoproteins, which are vital for antioxidant defense, thyroid hormone metabolism, and immune function. Selenium deficiency can lead to several health issues, including impaired immune response and increased oxidative stress.
Indications
- Selenium deficiency
- Supportive therapy in conditions requiring antioxidant support
- Potential adjunct in cancer prevention strategies
Dosage
Children: Refer to BNF for Children for specific dosing information.
Adults: Initially 100–500 micrograms daily, adjusted according to response and serum levels.
Mechanism of action
Selenium is metabolized to selenophosphate and selenocysteine, which are essential for the synthesis of selenoproteins. This process involves the incorporation of selenium into proteins through a specialized tRNA that recognizes the RNA sequence UGA, which is facilitated by SECIS structures and SBP-2 proteins. Key selenoproteins, like glutathione peroxidases, help protect cells from oxidative damage, thus playing a significant role in reducing the risk of diseases such as atherosclerosis and certain cancers.
Pharmacodynamics
Selenium is incorporated into various selenoproteins that perform essential functions, including antioxidant activity, redox balance, and regulation of thyroid hormones. Its role in antioxidant defense mechanisms is particularly important for protecting cells against reactive oxygen species (ROS). Selenium supplementation has been linked to improved immune function and potential cancer prevention.
Pharmacokinetics
Selenium is absorbed through the gastrointestinal tract, and its bioavailability can vary based on the source and form of selenium. Once absorbed, it is distributed to various tissues, where it is incorporated into selenoproteins. Selenium is primarily excreted through urine, and its half-life can depend on dietary intake and individual metabolism. Selenium status can be assessed through blood levels of selenoproteins and selenium itself.
Adverse effects
- Nausea
- Anaemia
- Aplastic anaemia
- Skin reactions
- Gastrointestinal disorders
Precautions
- Selenium supplementation should not be given unless there is good evidence of deficiency.
- Use caution in patients with a history of hypersensitivity to selenium or its compounds.
Pregnancy
Limited information is available regarding selenium supplementation during pregnancy. Consult specialist sources for guidance.
Breast-feeding
Limited information is available; the effect of selenium on copper levels in milk is conflicting, and its impact on the infant is unknown.
Storage
After opening, store in a refrigerator (2–8°C).
Formulations
- Tablets (e.g., L-Selenomethionine 200 micrograms, SelenoPrecise 100 micrograms)
- Capsules (e.g., Trientine dihydrochloride 250 mg)
- Injection solutions (e.g., Sodium selenite 50 micrograms per 1 ml)
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: black
Black is a term that can refer to various substances, but in pharmacological contexts, it is important to clarify the specific drug being referenced. Without additional information, it is challenging to provide a detailed monograph. Generally, drugs can have distinct properties, mechanisms of action, and therapeutic uses based on their chemical structures. Therefore, a precise identification is necessary for adequate information.
Dosage
Children: Refer to specific guidelines or literature for dosing information.
Adults: Refer to specific guidelines or literature for dosing information.
Pregnancy
Consult healthcare professionals before use. Safety during pregnancy is not well established.
Breast-feeding
Consult healthcare professionals before use. Safety during breastfeeding is not well established.
Storage
Store in a cool, dry place away from direct sunlight.
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: elemental
Elemental refers to elemental nutritional formulations that provide essential nutrients in their simplest forms. These formulations are used primarily to treat patients with specific nutritional deficiencies, malabsorption syndromes, or conditions where gastrointestinal function is impaired. Elemental diets are often used in conditions such as Crohn's disease, cystic fibrosis, and short bowel syndrome, and can be administered orally or via enteral feeding.
Indications
- Malabsorption syndromes
- Crohn's disease
- Cystic fibrosis
- Short bowel syndrome
- Severe food allergies
- Inability to meet nutritional needs through standard diets
Dosage
Children: Refer to specific formulations for dosing, as paediatric dosages depend on the product and the child's nutritional needs.
Adults: Refer to specific formulations for dosing, as adult dosages vary based on the product used and the patient's nutritional requirements.
Mechanism of action
Elemental formulations provide nutrients in their simplest forms, which are readily absorbed in the small intestine. This bypasses complex digestive processes, making them suitable for individuals with compromised digestion or absorption capabilities. The nutrients in these formulations include amino acids, simple carbohydrates, and fatty acids, which can be directly utilized by the body's metabolic pathways.
Pharmacodynamics
Elemental formulations help restore nutritional balance by supplying essential macronutrients and micronutrients needed for metabolic processes. They support growth, maintain energy levels, and promote healing in patients with malabsorption or increased nutritional needs. The bioavailability of nutrients in elemental forms is typically high, allowing for efficient uptake and utilization by the body.
Pharmacokinetics
Following administration, elemental nutrients are absorbed in the gastrointestinal tract, primarily in the jejunum and ileum. The rate of absorption can vary based on the specific formulation and the individual's gastrointestinal health. Once absorbed, these nutrients enter systemic circulation and are transported to various tissues for utilization in metabolic processes. The elimination of unabsorbed nutrients occurs primarily through feces.
Adverse effects
- Nausea
- Vomiting
- Diarrhea
- Constipation
- Stomach cramps
- Dark stools
- Metallic taste
- Allergic reactions
Precautions
- Use with caution in patients with a history of gastrointestinal disorders.
- Monitor for signs of iron overload in patients receiving multiple iron products.
- Assess for the need for supplementation in patients with conditions causing malabsorption.
Pregnancy
Iron is essential during pregnancy, but supplementation should be guided by clinical need and under healthcare supervision.
Breast-feeding
Iron is excreted in breast milk; supplementation may be necessary depending on maternal iron status.
Storage
Store in a cool, dry place, away from direct sunlight and moisture. Keep out of reach of children.
Formulations
- Oral tablets
- Liquid formulations
- Injectable solutions
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: extract
Extracts are concentrated preparations obtained from plants, herbs, or other natural sources through various extraction methods such as solvent extraction, steam distillation, or cold pressing. They are used for their therapeutic properties in herbal medicine and can contain a variety of bioactive compounds including alkaloids, flavonoids, terpenes, and essential oils. The specific effects and uses of an extract depend on its source material and the compounds it contains.
Indications
- General wellness support
- Anti-inflammatory effects
- Antioxidant activity
- Digestive aid
- Support for immune function
Dosage
Children: Paediatric dosing should be determined based on the specific extract and its intended use. Consultation with a healthcare provider is recommended for accurate dosing.
Adults: Dosage varies widely depending on the specific extract and formulation. It is essential to follow the manufacturer's instructions or consult a healthcare professional for appropriate dosing.
Mechanism of action
The mechanism of action of herbal extracts can vary significantly based on their constituents. Commonly, they exert their effects through multiple pathways including modulation of neurotransmitter systems, interference with inflammatory processes, or direct antioxidant activity. Some extracts may activate certain receptors or inhibit enzymes related to disease processes.
Pharmacodynamics
The pharmacodynamics of extracts is complex due to the presence of multiple active compounds which can have synergistic or antagonistic effects. These compounds may influence cellular signaling pathways, alter gene expression, or modulate immune response. The overall pharmacological profile is determined by the specific composition of the extract, its concentration, and the biological target it interacts with.
Pharmacokinetics
The pharmacokinetics of extracts involves absorption, distribution, metabolism, and excretion of the active compounds. Generally, herbal extracts are absorbed in the gastrointestinal tract, with bioavailability influenced by factors such as formulation, the presence of food, and individual metabolic differences. Compounds may undergo hepatic metabolism, and elimination can occur through urine or feces, depending on their chemical nature.
Pregnancy
Consult a healthcare professional before use, as the safety of the extract during pregnancy has not been established.
Breast-feeding
Consult a healthcare professional before use, as the safety of the extract during breastfeeding has not been established.
Storage
Store in a cool, dry place away from direct sunlight. Keep out of reach of children.
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: larginine
BNF-referencedL-arginine is a semi-essential amino acid that serves as a precursor for nitric oxide (NO) production in the body. It plays critical roles in various physiological processes, including cardiovascular function, immune response, and tissue repair. L-arginine supplementation is often utilized for its potential benefits in enhancing blood flow, promoting wound healing, and supporting muscle growth.
Indications
- Cardiovascular diseases
- Erectile dysfunction
- Peripheral arterial disease
- Wound healing
- Muscle growth and recovery
- Immune system support
Dosage
Children: For paediatric dosing, it is important to refer to the BNF for Children for appropriate guidelines based on the child's age, weight, and clinical condition.
Adults: The typical dosage for adults varies based on the condition being treated, but common oral doses range from 2 to 30 grams per day, divided into multiple doses. For specific dosing recommendations, please refer to the BNF.
Mechanism of action
L-arginine is converted to nitric oxide by nitric oxide synthase (NOS), which is crucial for vascular function and blood flow regulation. NO activates guanylate cyclase, leading to increased levels of cyclic GMP, a secondary messenger that mediates vasodilation and other cellular responses. This pathway is vital in both the cardiovascular and immune systems, with different isoforms of NOS (eNOS, nNOS, iNOS) contributing to various physiological effects.
Pharmacodynamics
L-arginine has been shown to enhance immune responses, improve wound healing, stimulate growth hormone release, and support muscle hypertrophy and tissue repair. Its role in nitric oxide production aids in vasodilation, improving blood circulation and oxygen delivery to tissues, which is essential for recovery and regeneration.
Pharmacokinetics
L-arginine is absorbed from the gastrointestinal tract, with peak plasma concentrations occurring within 1-2 hours after oral administration. It is metabolized primarily in the liver and kidneys, with a half-life of approximately 1-2 hours. The bioavailability of L-arginine can be influenced by dietary intake and metabolic conditions.
Adverse effects
- Gastrointestinal disturbances
- Nausea
- Diarrhea
- Abdominal pain
- Hypotension
- Allergic reactions
Interactions
- Antihypertensive agents may have additive effects leading to increased hypotension
- Sildenafil and other medications for erectile dysfunction may have enhanced effects when used with L-arginine
Precautions
- Caution in patients with a history of asthma or allergies
- Use with caution in patients with hypotension
- Monitor blood pressure in patients taking antihypertensive medications
Pregnancy
The safety of L-arginine in pregnancy has not been established. Consult a healthcare provider before use.
Breast-feeding
L-arginine is excreted in breast milk, and its safety during breastfeeding is not well established. Consult a healthcare provider.
Storage
Store in a cool, dry place away from direct sunlight. Keep out of reach of children.
Formulations
- Oral tablets
- Powder for oral solution
- Capsules
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: lycopene
BNF-referencedLycopene is a naturally occurring carotenoid found predominantly in tomatoes and other red fruits. It is known for its potent antioxidant properties and its potential role in reducing the risk of certain cancers, particularly lung and prostate cancers. Lycopene has garnered attention for its ability to interfere with cancer cell growth and proliferation through various cellular mechanisms.
Indications
- Dietary supplement for antioxidant support
- Potential risk reduction for prostate cancer
- Potential risk reduction for lung cancer
Dosage
Children: Refer to specific guidelines as dosing can vary based on the formulation and purpose of use.
Adults: Refer to specific guidelines as dosing can vary based on the formulation and purpose of use.
Mechanism of action
Lycopene functions as a very potent antioxidant, trapping singlet oxygen and reducing mutagenesis. It inhibits cancer cell growth by disrupting growth factor receptor signaling and cell cycle progression. Lycopene upregulates connexin 43, enhancing gap junctional communication which is often deficient in tumors. Furthermore, it exhibits synergistic effects on cell proliferation and differentiation when combined with 1,25-dihydroxyvitamin D3, indicating interactions at a nuclear or subcellular level.
Pharmacodynamics
Lycopene's antioxidant properties play a critical role in protecting cells from oxidative stress. By trapping reactive oxygen species, it lessens cellular damage and may help to prevent the initiation and progression of cancer. Its ability to modulate cell signaling pathways and improve gap junction communication contributes to its anticancer effects. The interactions with vitamin D3 suggest a complex role in regulating cellular functions.
Pharmacokinetics
Lycopene is absorbed in the intestine and can be detected in the serum and various tissues. Its bioavailability can be influenced by dietary factors, including fat intake, which enhances absorption. Once in the body, lycopene is stored in adipose tissue and the liver. The elimination half-life and exact metabolic pathways are not well defined, but it is believed to undergo some conversion into other metabolites before excretion.
Pregnancy
There is insufficient reliable information regarding the safety of lycopene during pregnancy. Caution is advised.
Breast-feeding
Lycopene is considered safe during breastfeeding, but data on its excretion in human milk is limited.
Storage
Store in a cool, dry place, away from light.
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: pepper
Pepper, specifically black pepper (Piper nigrum), is a commonly used spice known for its pungent flavor and potential health benefits. It contains the active compound piperine, which is responsible for its characteristic taste and may have various pharmacological effects. Pepper is used in culinary applications and traditional medicine, and it has been studied for its ability to enhance the bioavailability of certain nutrients and drugs.
Dosage
Children: Refer to specific formulations and uses as per the BNF for Children.
Adults: Refer to specific formulations and uses as per the BNF.
Mechanism of action
Piperine, the primary active component of black pepper, enhances the absorption of various nutrients and drugs by inhibiting certain drug-metabolizing enzymes and transport proteins in the intestines and liver. It is known to inhibit UDP-glucuronosyltransferases, which are involved in drug metabolism, thereby potentially increasing the bioavailability of co-administered substances.
Pharmacodynamics
Piperine exhibits several pharmacological effects including antioxidant activity, anti-inflammatory properties, and potential anticancer effects. It may enhance thermogenesis and fat metabolism, contributing to weight management. Additionally, piperine can influence the pharmacokinetics of other drugs by inhibiting their metabolism, leading to increased plasma concentrations.
Pharmacokinetics
Piperine is rapidly absorbed from the gastrointestinal tract and undergoes extensive metabolism in the liver. It has a relatively short half-life, and its effects on drug metabolism can lead to altered pharmacokinetics of concomitantly administered drugs. The bioavailability of piperine itself may be low, but its ability to enhance the absorption of other compounds is significant.
Interactions
- peppermint oil + lomitapide: Unknown (increases exposure)
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: policosanol
Policosanol is a natural substance derived from the waxy coating of sugarcane, though it can also be obtained from other plant sources. It is primarily marketed as a dietary supplement for its purported cholesterol-lowering effects. Policosanol has gained attention for its potential to improve lipid profiles and promote cardiovascular health, although the evidence regarding its efficacy varies.
Indications
- Hyperlipidemia
- High cholesterol levels
- Cardiovascular health support
Dosage
Children: Not established; refer to a healthcare professional for guidance.
Adults: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing recommendations, as policosanol is available in various formulations.
Mechanism of action
Policosanol is believed to exert its effects through multiple mechanisms, including inhibition of cholesterol synthesis in the liver and enhancement of cholesterol clearance from the bloodstream. It may also influence the metabolism of lipoproteins, leading to a decrease in low-density lipoprotein (LDL) and total cholesterol levels while potentially increasing high-density lipoprotein (HDL) levels.
Pharmacodynamics
The pharmacodynamics of policosanol include its ability to modulate lipid metabolism and favorably alter serum lipid concentrations. It may also exhibit antioxidant properties, contributing to its cardiovascular benefits by reducing oxidative stress and inflammation in vascular tissues.
Pharmacokinetics
Policosanol is typically administered orally and has variable absorption rates, influenced by factors such as dosage form and presence of dietary fats. The elimination half-life and specific metabolic pathways are not well characterized in the literature, leading to some uncertainty regarding its pharmacokinetics. However, it is noted that repeated doses may be necessary to achieve therapeutic effects, and accumulation in the body may occur with prolonged use.
Adverse effects
- Headache
- Dizziness
- Nausea
- Diarrhea
- Skin rash
Interactions
- Potential interactions with anticoagulants
- May enhance the effects of antiplatelet agents
Precautions
- Use with caution in patients with hepatic impairment
- Monitor for bleeding in patients taking anticoagulants or antiplatelet medications
Pregnancy
There is limited information on the safety of policosanol during pregnancy. It is advisable to avoid use unless clearly needed.
Breast-feeding
There is insufficient data on the excretion of policosanol in human milk. Caution is recommended when administering to nursing mothers.
Storage
Store in a cool, dry place away from direct sunlight. Keep out of reach of children.
Formulations
- Oral tablets
- Capsules
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Clinical monograph: tocopherol
BNF-referencedTocopherol, commonly known as vitamin E, is a fat-soluble antioxidant that plays a critical role in protecting cell membranes from oxidative stress. It is primarily found in various dietary sources, including nuts, seeds, and green leafy vegetables. Tocopherol acts by donating hydrogen atoms to free radicals, thereby neutralizing their harmful effects and preventing cellular damage.
Indications
- Prevention of vitamin E deficiency
- Antioxidant therapy
- Support in conditions related to oxidative stress
Dosage
Children: Refer to BNF for Children for specific dosage guidelines.
Adults: Refer to BNF for specific dosage guidelines.
Mechanism of action
Tocopherol acts as a radical scavenger, primarily functioning as an antioxidant for lipid bilayers. It donates hydrogen atoms to free radicals, trapping them and preventing cellular damage. Its effectiveness is influenced by its location within the membrane and its interaction with cytosolic reductants like ascorbate. Tocopherol can trap multiple radicals, including alkyl and peroxy radicals.
Pharmacodynamics
The antioxidant properties of tocopherol lead to significant pharmacodynamic effects, including the inhibition of cell death through modulation of protein kinase C (PKC). Tocopherol also exhibits anti-inflammatory effects, which can be attributed to its influence on cytokines, prostaglandins, prostanoids, and thromboxanes. These interactions may contribute to its protective effects in various pathological conditions.
Pharmacokinetics
Tocopherol is absorbed in the intestines and its bioavailability can be influenced by dietary fat intake. It is transported in the plasma primarily bound to lipoproteins. Tocopherol is stored in adipose tissue and the liver, and its elimination occurs through bile and urine. The half-life of tocopherol can vary depending on the individual's nutritional status and other factors.
Pregnancy
Tocopherol is generally considered safe during pregnancy, but it is advisable to consult a healthcare provider before use.
Breast-feeding
Tocopherol is excreted in breast milk, and while it is considered safe, a healthcare provider should be consulted for specific recommendations.
Storage
Store in a cool, dry place away from direct sunlight.
AI-synthesized from BNF references - general information only, not a substitute for professional medical advice or the current BNF. Verify doses with a pharmacist.
Molecular reference: Selenium
PubChem CID 6326970Molecular formula: Se
Mechanism of action
Selenium is first metabolized to selenophosphate and selenocysteine. Selenium incorporation is genetically encoded through the RNA sequence UGA. This sequence is recognized by RNA ste loop structures called selenocysteine inserting sequences (SECIS). These structures require the binding of SECIS binding proteins (SBP-2) to recognize selenocystiene. The specialized tRNA is first bound to a serine residue which is then enzymatically processed to a selylcysteyl-tRNA by selenocystiene sythase using selenophosphate as a selenium donor. Other unidentified proteins are required as part of the binding of this tRNA to the ribosome. Selenoproteins appear to be necessary for life as mice with the specialized tRNA gene knocked out exhibited early embryonic lethality. The most important selenoproteins seem to be the glutathione peroxidases and thioredoxin reductases which are part of the body's defenses againts reactive oxygen species (ROS). The importance of selenium in these anti-oxidant proteins has been implicated in the reduction of atherosclerosis by preventing the oxidation of low density lipoprotein. Selenium supplementation is also being investigated in the prevention of cancer and has been suggested to be beneficial to immune function. Converging data from epidemiological, ecological, and clinical studies have shown that selenium (Se) can decrease the risk for some types of human cancers. Induction of apoptosis is considered an important cellular event that can account for the cancer preventive effects of Se. Prior to occurrence of apoptosis, Se compounds alter the expression and/or activities of signaling molecules, mitochondria-associated factors, transcriptional factors, tumor suppressor genes, and cellular reduced glutathione. Mechanistic studies have demonstrated that the methylselenol metabolite pool has many desirable attributes of chemoprevention, whereas the hydrogen selenide pool with excess of selenoprotein synthesis can lead to DNA single-strand breaks. To elucidate the effects of Se on cytotoxic events, it should be remembered that the chemical forms and the dose of Se, and the experimental system used, are determinants of its biological activities. This mini-review focuses on elucidation of the molecular mechanisms of cancer prevention by Se with the apoptotic approach. /Selenium/ Selenium status can also influence thyroid hormone function via the deiodinase enzymes. Selenium is a critical component of the deiodinase enzymes, including iodothyronine 5'-deiodinases, which convert the prohormone thyroxine (T4) to the active circulating form, triiodothyronine (T3). Selenium is also a component of GPX, the main enzyme responsible for protecting thyroid cells against oxidative damage. GPX is involved in the detoxification of hydrogen peroxide, which is produced in the thyroid during the conversion of T4 to T3. /Selenium/ Selenium readily substitutes for sulfur in biomolecules and in many biochemical reactions, especially when the concentration of selenium is high and the concentration of sulfur is low in the organism. Inactivation of the sulfhydryl enzymes necessary for oxidative reactions in cellular respiration, through effects on mitochondrial and microsomal electron transport, might contribute to acute selenium toxicity. Selenium may have a role in hepatic heme metabolism that is related to GPX or lipid peroxidation. Selenocysteine is specifically found in some proteins (e.g., glutathione peroxidase); selenomethionine appears to randomly substitute for methionine in protein synthesis. This appears to be an additional mechanism for intermediate- or chronic-duration toxicity. Skin, hair, and nail damage are significant indicators of chronic selenium overexposure. The mechanism causing these integumentary effects is unclear, but could be related to the high selenium concentrations in these tissues as a consequence of the substitution of selenium for sulfur in certain amino acids, including the disulfide bridges that pr
Pharmacodynamics
Selenium is incorporated into many different selenoproteins which serve various functions throughout the body.
Biological pathways
Source: PubChem (NCBI) · pathways from PathBank, Reactome, WikiPathways & PharmGKB.
Molecular reference: l-arginine
PubChem CID 6322Molecular formula: C6H14N4O2
Mechanism of action
Many of supplemental L-arginine's activities, including its possible anti-atherogenic actions, may be accounted for by its role as the precursor to nitric oxide or NO. NO is produced by all tissues of the body and plays very important roles in the cardiovascular system, immune system and nervous system. NO is formed from L-arginine via the enzyme nitric oxide synthase or synthetase (NOS), and the effects of NO are mainly mediated by 3,'5' -cyclic guanylate or cyclic GMP. NO activates the enzyme guanylate cyclase, which catalyzes the synthesis of cyclic GMP from guanosine triphosphate or GTP. Cyclic GMP is converted to guanylic acid via the enzyme cyclic GMP phosphodiesterase. NOS is a heme-containing enzyme with some sequences similar to cytochrome P-450 reductase. Several isoforms of NOS exist, two of which are constitutive and one of which is inducible by immunological stimuli. The constitutive NOS found in the vascular endothelium is designated eNOS and that present in the brain, spinal cord and peripheral nervous system is designated nNOS. The form of NOS induced by immunological or inflammatory stimuli is known as iNOS. iNOS may be expressed constitutively in select tissues such as lung epithelium. All the nitric oxide synthases use NADPH (reduced nicotinamide adenine dinucleotide phosphate) and oxygen (O2) as cosubstrates, as well as the cofactors FAD (flavin adenine dinucleotide), FMN (flavin mononucleotide), tetrahydrobiopterin and heme. Interestingly, ascorbic acid appears to enhance NOS activity by increasing intracellular tetrahydrobiopterin. eNOS and nNOS synthesize NO in response to an increased concentration of calcium ions or in some cases in response to calcium-independent stimuli, such as shear stress. In vitro studies of NOS indicate that the Km of the enzyme for L-arginine is in the micromolar range. The concentration of L-arginine in endothelial cells, as well as in other cells, and in plasma is in the millimolar range. What this means is that, under physiological conditions, NOS is saturated with its L-arginine substrate. In other words, L-arginine would not be expected to be rate-limiting for the enzyme, and it would not appear that supraphysiological levels of L-arginine which could occur with oral supplementation of the amino acid^would make any difference with regard to NO production. The reaction would appear to have reached its maximum level. However, in vivo studies have demonstrated that, under certain conditions, e.g. hypercholesterolemia, supplemental L-arginine could enhance endothelial-dependent vasodilation and NO production.
Pharmacodynamics
Studies have shown that is has improved immune responses to bacteria, viruses and tumor cells; promotes wound healing and regeneration of the liver; causes the release of growth hormones; considered crucial for optimal muscle growth and tissue repair.
Biological pathways
Source: PubChem (NCBI) · pathways from PathBank, Reactome, WikiPathways & PharmGKB.
Molecular reference: lycopene
PubChem CID 446925Molecular formula: C40H56
Mechanism of action
Serum and tissue lycopene levels have been inversely related to the risk of lung and prostate cancers. Lycopene functions as a very potent antioxidant, and it can trap singlet oxygen and reduce mutagenesis in the Ames test. Lycopene at physiological concentrations can inhibit human cancer cell growth by interfering with growth factor receptor signaling and cell cycle progression. Studies using human and animal cells identified connexin 43, a gene whose expression is upregulated by lycopene and which allows direct intercellular gap junctional communication (GJC). GJC is deficient in many human tumors and its restoration or upregulation is associated with decreased proliferation. The combination of low concentrations of lycopene with 1,25-dihydroxyvitamin D3 exhibits a synergistic effect on cell proliferation and differentiation, and an additive effect on cell cycle progression in the HL-60 promyelocytic leukemia cell line, suggesting some interaction at a nuclear or subcellular level.
Biological pathways
Source: PubChem (NCBI) · pathways from PathBank, Reactome, WikiPathways & PharmGKB.
Molecular reference: tocopherol
PubChem CID 14986Molecular formula: C28H48O2
Mechanism of action
Tocopherol acts as a radical scavenger. It mainly acts as an antioxidant for lipid bilayers. Tocopherol's functions depend on the H-atom donating ability, location, and movement within the membrane, as well as the efficiency in the radical recycling by some cytosolic reductants such as ascorbate. Tocopherol actions are related to the trap of radicals, and it has been shown that even in the absence of substituents in the ortho-positions, tocopherol can trap more than two radicals. The type of radicals available for tocopherol are alkyl and peroxy.
Pharmacodynamics
The antioxidant effects of tocopherol can be translated into different changes at the pharmacodynamic level. In vitro studies have shown that this antioxidant activity can produce modification in protein kinase C (PKC) which will later be translated into an inhibition of cell death. Some other derivate effects are the anti-inflammatory properties of tocopherol which can be related to the modulation of cytokines or prostaglandins, prostanoids and thromboxanes.
Source: PubChem (NCBI) · pathways from PathBank, Reactome, WikiPathways & PharmGKB.
This drug in other countries
The same active ingredient registered across other registries we cover - including different brands.