TRYCEPTION TABLETS (Each film-coated tablet contains Vit C/Vit D3/Vit E/Vit B1/Vit B2/Vit B3/Vit B6/Folic Acid/Vit B12/Zinc/Selenium/Chromium/L-Arginine/L-Carnitine/CoQ10/Inositol/Ginseng Extract/Maca Extract/Lycopene Extract 90mg/600iu/30mg/12mg/5mg/18mg/10mg/400mcg/75mcg/6mg/15mg/150mcg/50mcg/10mg/50mg/2mg/40mg/30mg/250mg/1.5mg)

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)

Indications

• Type 2 diabetes mellitus
• Insulin resistance
• Impaired glucose tolerance
• Metabolic syndrome
• Hyperlipidemia

Dosage

Children: Refer to the BNF for Children for specific dosage recommendations suitable for pediatric patients.

Adults: Refer to the BNF for specific dosage recommendations based on the condition being treated.

Mechanism of action

Chromium enhances insulin signaling by upregulating insulin receptor-mediated pathways. It affects downstream effector molecules after insulin binds to its receptor, leading to the activation of phosphatidylinositol 2-kinase (PI3K) and protein kinase B (Akt). This process promotes the translocation of glucose transporter-4 (Glut4) to the cell membrane, facilitating increased glucose uptake. Additionally, chromium can promote GLUT-4 transporter translocation independently of insulin receptor activity under insulin-resistant conditions and aids in cholesterol efflux by increasing membrane fluidity.

Pharmacodynamics

Trivalent chromium is essential for the glucose tolerance factor, which activates insulin-mediated pathways. It enhances insulin binding to cells, increases the density of insulin receptors, and activates insulin receptor kinase, all of which contribute to improved insulin sensitivity. Chromium deficiency can lead to impaired glucose metabolism, and supplementation can normalize glucose tolerance in individuals exhibiting diabetic-like characteristics due to deficiency.

Pharmacokinetics

Chromium absorption occurs primarily in the intestines, but its bioavailability is influenced by various dietary factors, such as the presence of other minerals and vitamins. The mineral is transported in the bloodstream bound to transferrin and is predominantly stored in the liver, spleen, and bone. The elimination of chromium occurs mainly through urine, with small amounts excreted in feces. The half-life and exact metabolic pathways for chromium can vary based on its form and the individual's nutritional status.

Pregnancy

Chromium is generally considered safe during pregnancy when taken in appropriate amounts, but it is advisable to consult a healthcare provider.

Breast-feeding

Chromium is excreted in breast milk, and while it is deemed safe in moderate amounts, consultation with a healthcare provider is recommended.

Storage

Store in a cool, dry place away from light. Keep out of reach of children.

Indications

• Heart failure
• Hypertension
• Statin myopathy
• Cancer

Dosage

Children: Refer to BNF for Children for specific dosing information in paediatric patients.

Adults: Refer to BNF for specific dosing information based on the clinical condition being treated.

Mechanism of action

Ubidecarenone is an essential cofactor in the mitochondrial electron transport chain. Its primary functions include the acceptance of electrons from complexes I and II, which is vital for ATP production. Additionally, it acts as a mobile redox agent, shuttling electrons and protons in the electron transport chain. Ubidecarenone also provides antioxidant activity in mitochondria and cellular membranes, protecting against lipid peroxidation and inhibiting the oxidation of LDL-cholesterol.

Pharmacodynamics

Ubidecarenone has roles in various physiological processes, including sulfide oxidation, regulation of the mitochondrial permeability transition pore, and the translocation of protons and calcium ions across biological membranes. Research indicates its potential benefits in treating conditions such as cancer, statin myopathy, congestive heart failure, and hypertension.

Pharmacokinetics

Coenzyme Q10 is absorbed in the small intestine, with bioavailability affected by dietary fats. Once absorbed, it is distributed throughout body tissues, particularly in the heart, liver, and kidneys. The half-life of CoQ10 is approximately 33 hours, and it is metabolized primarily in the liver. Excretion occurs mainly through the bile and urine.

Pregnancy

There is insufficient evidence regarding the safety of CoQ10 during pregnancy. Consult a healthcare professional before use.

Breast-feeding

Limited data suggests that CoQ10 is likely safe during breastfeeding, but consult a healthcare professional for personalized advice.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Capsules
• Tablets
• Soft gels

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.

Indications

• Folate deficiency
• Megaloblastic anemia
• Prevention of neural tube defects in pregnancy
• Supplementation in patients on certain medications (e.g., methotrexate)

Dosage

Children: Refer to the BNF for Children for appropriate pa

Adults: Refer to specific guidelines or the BNF for appropriate adult dosing based on the indication.

Mechanism of action

Folate functions as a coenzyme in the conversion of homocysteine to methionine, a process that is vital for DNA synthesis and repair. It is involved in the one-carbon metabolism pathway, where it acts as a carrier of one-carbon units necessary for the synthesis of purines and thymidylate, thus supporting the production of nucleotides and DNA. This mechanism is particularly important in rapidly dividing cells.

Pharmacodynamics

Folate is critical for the formation of red blood cells and the proper functioning of the nervous system. It aids in the production of nucleic acids, which are essential for cell proliferation. Folate deficiency can lead to impaired DNA synthesis, resulting in megaloblastic anemia characterized by the presence of large, immature red blood cells in the bloodstream. Adequate folate levels are also associated with reduced risk of neural tube defects in developing fetuses.

Pharmacokinetics

Folate is absorbed in the proximal part of the small intestine, primarily in the jejunum, and is transported in the bloodstream bound to plasma proteins. It undergoes hepatic metabolism and is stored mainly in the liver. The elimination half-life varies, but dietary folate can be retained in the body for several weeks. Excess folate is excreted through the urine. The bioavailability of folate from food sources is lower compared to synthetic folic acid found in supplements.

Interactions

• folates+fluorouracil: Severe (increases risk of toxicity)
• folates+antiepileptics: Moderate (decreases concentration)
• folates+fosphenytoin: Moderate (decreases concentration)
• folates+phenobarbital: Moderate (decreases concentration)
• folates+phenytoin: Moderate (decreases concentration)
• folates+primidone: Moderate (decreases concentration)
• sulfasalazine+folates: Unknown (decreases absorption)

Pregnancy

Folate is essential for fetal development and is often recommended to prevent neural tube defects.

Breast-feeding

Folate is generally safe during breastfeeding, as it is important for both maternal and infant health.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Tablets
• Injection

Indications

• Fatigue
• Stress management
• Cognitive enhancement
• Immune support
• General well-being

Dosage

Children: Refer to specific product guidelines, as dosing in children should be determined by a healthcare professional.

Adults: Refer to specific product guidelines, as dosing can vary based on formulation and intended use.

Mechanism of action

Ginseng is thought to exert its effects through several mechanisms, including modulation of the hypothalamic-pituitary-adrenal (HPA) axis, enhancement of antioxidant activity, and regulation of neurotransmitter levels. Ginsenosides, the active compounds in ginseng, may influence cellular signaling pathways, promote neuroprotection, and enhance immune responses.

Pharmacodynamics

The pharmacodynamic effects of ginseng are attributed primarily to its active constituents, ginsenosides, which interact with various receptors and enzymes in the body. These interactions can lead to increased energy metabolism, improved cognitive function, enhanced physical performance, and modulation of the immune system. Ginseng may also exhibit adaptogenic properties, helping the body to maintain homeostasis under stress.

Pharmacokinetics

Ginsenosides undergo extensive metabolism in the body, primarily by the liver. Bioavailability can vary significantly based on the specific ginsenoside and the method of administration. Ginseng is usually administered orally, with effects typically observed within several hours after ingestion. The elimination half-life of ginsenosides can vary based on the specific compound and individual metabolism, with some studies suggesting that effects may persist for several hours to days.

Adverse effects

• Insomnia
• Headache
• Gastrointestinal disturbances
• Nervousness
• Hypertension
• Allergic reactions

Interactions

• May interact with anticoagulants (e.g., warfarin)
• May enhance the effects of caffeine
• May affect insulin levels and blood sugar control
• Potential interaction with immunosuppressants

Precautions

• Use with caution in patients with hypertension
• May cause sleep disturbances; avoid use before bedtime
• Should be used cautiously in patients with diabetes
• Consult a healthcare provider before use in individuals with autoimmune conditions

Pregnancy

Limited data available. Generally not recommended due to potential hormonal effects.

Breast-feeding

Limited data available. Consult a healthcare provider before use.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Dried root
• Powdered extract
• Capsules
• Tinctures
• Teas

Indications

• Polycystic ovary syndrome (PCOS)
• Generalized anxiety disorder
• Depression
• Obsessive-compulsive disorder
• Insulin resistance

Dosage

Children: Refer to the BNF for Children for appropriate dosing guidelines for paediatric patients.

Adults: Refer to the BNF for specific dosing recommendations, as doses may vary based on the condition being treated.

Mechanism of action

Inositol functions primarily as a precursor for the synthesis of phosphoinositides, which are key components of cell membranes. These phosphoinositides are involved in various intracellular signaling pathways, particularly those mediated by G-protein coupled receptors. Inositol also influences the action of neurotransmitters such as serotonin and has been shown to enhance insulin sensitivity and glucose metabolism.

Pharmacodynamics

Inositol has been observed to have mood-stabilizing effects and may improve insulin sensitivity. Its role in cell signaling impacts various physiological processes, including cellular communication and metabolic regulation. The therapeutic effects of inositol in psychiatric conditions may be attributed to its ability to modulate neurotransmitter systems, particularly involving serotonin and dopamine.

Pharmacokinetics

Inositol is well-absorbed from the gastrointestinal tract, with peak plasma levels occurring within 1 to 2 hours after ingestion. It is distributed throughout the body and can cross the blood-brain barrier. Inositol is predominantly excreted in the urine, with a half-life that varies based on dosage and individual metabolism. Metabolism occurs primarily through dephosphorylation to form various inositol phosphates.

Pregnancy

Inositol is generally considered safe during pregnancy but should be used under medical supervision.

Breast-feeding

Inositol is likely safe during breastfeeding, but consult a healthcare provider for specific recommendations.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Formulations

• Powder
• Capsules

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

Mechanism of action

Levocarnitine acts as a carrier molecule for long-chain fatty acids, transporting them into mitochondria for beta-oxidation, which is critical for energy production. It also exports acyl groups from subcellular organelles and cells to urine, preventing toxic accumulation. The mechanism of action includes interactions with carnitine transporters, translocases, and acetyltransferases. Additionally, it normalizes the brain's redox state and enhances urea synthesis in the liver, potentially activating the glucocorticoid receptor. L-carnitine's antagonistic effects on thyroid hormone action, including inhibiting its nuclear entry, contribute to its therapeutic applications.

Pharmacodynamics

Levocarnitine plays a significant role in lipid metabolism and energy production through its involvement in the transport of fatty acids into the mitochondria. A deficiency in carnitine can lead to various metabolic issues, including liver, heart, and muscle dysfunction. The therapeutic use of levocarnitine includes its ability to stimulate gastric and pancreatic secretions and treat hyperlipoproteinemias. The L-isomer of carnitine is specifically active in lipid metabolism, and its deficiency can be identified through biochemical markers such as low plasma concentrations of free carnitine and elevated acylcarnitine levels.

Pharmacokinetics

Levocarnitine is absorbed in the intestines and distributed throughout the body tissues. It is primarily metabolized in the liver, with excretion occurring via urine. The pharmacokinetics of levocarnitine can vary based on dietary intake, physiological status, and specific health conditions that may affect its metabolism and clearance. The bioavailability of levocarnitine may also be

Adverse effects

• Nausea
• Vomiting
• Abdominal cramps
• Diarrhea
• Fishy body odor
• Rash
• Seizures (rare)

Interactions

• Anticoagulants may have altered effects.
• Thyroid hormones may have altered action due to L-carnitine's peripheral antagonism.

Precautions

• Use with caution in patients with renal impairment.
• Monitor for potential interactions with other medications.

Pregnancy

Limited data is available on the use of levocarnitine during pregnancy. Use only if clearly needed and after assessing benefits versus risks.

Breast-feeding

Levocarnitine is excreted in human milk. Caution is advised when administered to nursing mothers.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Oral solution
• Tablets
• Capsules

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.

Indications

• Improvement of energy levels
• Enhancement of libido
• Support for fertility
• Relief from menopause symptoms
• Reduction of stress and fatigue

Dosage

Children: Maca is not typically recommended for children. Consult a healthcare provider for advice on use in pediatric populations.

Adults: Refer to product-specific guidelines or consult a healthcare provider for appropriate dosing, as there is no standardized dosage for maca.

Mechanism of action

Maca is thought to exert its effects through the modulation of hormone levels and the enhancement of energy metabolism. It may influence the hypothalamus and pituitary gland, leading to increased production of hormones such as testosterone and estrogen. Additionally, it contains unique compounds called macamides and macaenes, which are believed to have anabolic and adaptogenic properties, potentially enhancing physical performance and reducing stress.

Pharmacodynamics

Maca is known for its adaptogenic properties, which help the body adapt to stress and promote homeostasis. It may enhance libido and fertility by influencing hormonal balance. Some studies suggest that maca may also improve mood and cognitive function, possibly through its antioxidant properties and effects on neurotransmitter systems. However, further research is needed to fully understand its pharmacodynamic profile.

Pharmacokinetics

The pharmacokinetic profile of maca is not well-defined due to limited clinical studies. It is generally consumed in powdered form or as an extract, with absorption likely varying based on the preparation and individual metabolism. Maca is considered safe for most individuals when consumed in reasonable amounts, with most effects observed after prolonged use. The elimination route is not clearly established, but it is expected to be excreted through normal metabolic pathways.

Adverse effects

• Insomnia
• Nervousness
• Stomach upset
• Headache
• Increased heart rate

Interactions

• May interact with anticoagulants
• May enhance the effects of stimulants

Precautions

• Use with caution in individuals with hormone-sensitive conditions
• Consult a healthcare provider before use in patients with cardiovascular disease

Pregnancy

Limited data is available regarding the safety of maca during pregnancy. It is advisable to avoid use unless recommended by a healthcare professional.

Breast-feeding

Insufficient data is available on the safety of maca during breastfeeding. Consultation with a healthcare provider is recommended.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Powder
• Capsules
• Extracts

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.

Mechanism of action

Chromium is an essential nutrient involved in the metabolism of glucose, insulin and blood lipids. Its role in potentiating insulin signalling cascades has been implicated in several studies. Chromium upregulates insulin-stimulated insulin signal transduction via affecting effector molecules downstream of the insulin receptor (IR). IR-mediated signalling pathway involves phoshorylation of multiple intracellular domains and protein kinases, and downstream effector molecules. Upon activation by ligands, intracellular β-subunit of IR autophosphorylates and activates tyrosine kinase domain of the IR, followed by activation and phosphorylation of regulatory proteins and downstream signalling effectors including phosphatidylinositol 2-kinase (PI3K). PI3K activates further downstream reaction cascades to activate protein kinase B (Akt) to ultimately promote translocation of glucose transporter-4 (Glut4)-vesicles from the cytoplasm to the cell surface and regulate glucose uptake. Chromium enhances the kinase activity of insulin receptor β and increases the activity of downstream effectors, pI3-kinase and Akt. Under insulin-resistant conditions, chromium also promotes GLUT-4 transporter translocation that is independent of activity of IR, IRS-1, PI3-kinase, or Akt; chromium mediates cholesterol efflux from the membranes via increasing fluidity of the membrane by decreasing the membrane cholesterol and upregulation of sterol regulatory element-binding protein. As a result, intracellular GLUT-4 transporters are stimulated to translocate from intracellular to the plasma membrane, leading to enhanced glucose uptake in muscle cells. Chromium attenuates the activity of PTP-1B _in vitro,_ which is a negative regulator of insulin signaling. It also alleviates ER stress that is observed to be elevated the suppression of insulin signaling. ER stress is thought to activate c-Jun N-terminal kinase (JNK), which subsequently induces serine phosphorylation of IRS and aberration of insulin signalling. Transient upregulation of AMPK by chromium also leads to increased glucose uptake. While the toxicity of metals and metalloids, like arsenic, cadmium, mercury, lead and chromium, is undisputed, the underlying molecular mechanisms are not entirely clear. General consensus holds that proteins are the prime targets; heavy metals interfere with the physiological activity of specific, particularly susceptible proteins, either by forming a complex with functional side chain groups or by displacing essential metal ions in metalloproteins. Recent studies have revealed an additional mode of metal action targeted at proteins in a non-native state; certain heavy metals and metalloids have been found to inhibit the in vitro refolding of chemically denatured proteins, to interfere with protein folding in vivo and to cause aggregation of nascent proteins in living cells. Apparently, unfolded proteins with motile backbone and side chains are considerably more prone to engage in stable, pluridentate metal complexes than native proteins with their well-defined 3D structure. By interfering with the folding process, heavy metal ions and metalloids profoundly affect protein homeostasis and cell viability. This review describes how heavy metals impede protein folding and promote protein aggregation, how cells regulate quality control systems to protect themselves from metal toxicity and how metals might contribute to protein misfolding disorders.

Pharmacodynamics

Trivalent chromium is part of glucose tolerance factor, an essential activator of insulin-mediated reactions. Chromium helps to maintain normal glucose metabolism and peripheral nerve function. Chromium increases insulin binding to cells, increases insulin receptor density and activates insulin receptor kinase leading to enhanced insulin sensitivity. In chromium deficiency, intravenous administration of chromium resulted in normalization of the glucose tolerance curve from the diabetic-like curve typical of chromium deficiency.

Mechanism of action

Ubidecarenone is an essential cofactor in the mitochondrial electron transport chain. Its functions are the acceptance of electrons from the complex I and II and this activity is vital for the production of ATP. It acts as a mobile redox agent shuttling electrons and protons in the electron transport chain. Ubidecarenone also presents antioxidant activity in mitochondria and cellular membranes, protecting against peroxidation of lipid membranes as well as inhibiting oxidation of LDL-cholesterol.

Pharmacodynamics

Ubidecarenon has roles in many prysiological process including sulfide oxidation, regulation of mitochondrial permeability transition pore and translocation of protons and calcium ions accross biological membranes. Studies have shown its benefitial effect in treating cancer, statin myopathy, congestive heart failure and hypertension.

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.

Mechanism of action

Levocarnitine can be synthesised within the body from the amino acids lysine or methionine. Vitamin C (ascorbic acid) is essential to the synthesis of carnitine. Levocarnitine is a carrier molecule in the transport of long chain fatty acids across the inner mitochondrial membrane. It also exports acyl groups from subcellular organelles and from cells to urine before they accumulate to toxic concentrations. Only the L isomer of carnitine (sometimes called vitamin BT) affects lipid metabolism. Levocarnitine is handled by several proteins in different pathways including carnitine transporters, carnitine translocases, carnitine acetyltransferases and carnitine palmitoyltransferases. L-Carnitine is a peripheral antagonist of thyroid hormone action in some tissues. It inhibits thyroid hormone entry into cell nuclei. In a controlled clinical trial, L-carnitine was shown to reverse or prevent some symptoms of hyperthyroidism. ... Mortality and metabolic consequences of acute ammonium intoxication in mice are reduced by pharmacologic admin of L-carnitine. The mechanism for this effect may have 2 components. L-Carnitine admin normalizes the redox state of the brain (perhaps by incr the avail of beta-hydroxybutyrate and/or acetyl-L-carnitine to the brain), and it incr the rate of urea synth in the liver, perhaps in part by activation of the glucocorticoid receptor. At least part of the protective effect is associated with flux through the carnitine acyltransferases, as analogs of L-carnitine that are competitive inhibitors of carnitine acyltransferases enhance the toxicity of acute ammonium admin. Thus, it has been proposed that L-carnitine incr urea synth in the liver by facilitating fatty acid entry into mitochondria, leading to incr flux through the beta-oxidation pathway, an incr of intramitochondrial reducing equivalents, and enhancement of ATP production. ... Levocarnitine is necessary for normal mammalian fat utilization and energy metabolism. It facilitates entry of long-chain fatty acids into cellular mitochondria, where they are used during oxidation and energy production. It also exports acyl groups from subcellular organelles and from cells to urine before they accumulate to toxic concentrations. Carnitine's primary mechanism of action is apparently attributable to its role as a cofactor in the transformation of free long-chain fatty acids into acylcarnitines for subsequent transport into the mitochondrial matrix. Carnitine is involved in the metabolism of ketones for energy and the conversion of branched-chain amino acids - valine, leucine, and isoleucine - into energy. /Carnitine/ L-Carnitine participates in a reversible transesterification reaction, in which an acyl group is transferred from coenzyme A to the hydroxyl group of L-carnitine ... /This reaction facilitates the/ transfer of long-chain fatty acids from cytoplasm ... /and/ chain-shortened /very-long-chain/ fatty acids from peroxisomes to mitochondria /and the/ modulation of the acyl-CoA/CoA ratio in cellular compartments.

Pharmacodynamics

Levocarnitine is a carrier molecule in the transport of long chain fatty acids across the inner mitochondrial membrane. It also exports acyl groups from subcellular organelles and from cells to urine before they accumulate to toxic concentrations. Lack of carnitine can lead to liver, heart, and muscle problems. Carnitine deficiency is defined biochemically as abnormally low plasma concentrations of free carnitine, less than 20 µmol/L at one week post term and may be associated with low tissue and/or urine concentrations. Further, this condition may be associated with a plasma concentration ratio of acylcarnitine/levocarnitine greater than 0.4 or abnormally elevated concentrations of acylcarnitine in the urine. Only the L isomer of carnitine (sometimes called vitamin BT) affects lipid metabolism. The "vitamin BT" form actually contains D,L-carnitine, which competitively inhibits levocarnitine and can cause deficiency. Levocarnitine can be used therapeutically to stimulate gastric and pancreatic secretions and in the treatment of hyperlipoproteinemias.

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.