TRIMIX TABLET

Indications

• Heart disease prevention
• Weight management
• Digestive health
• Antioxidant support

Dosage

Children: There is no specific pediatric dosage for apples; they can be included in children's diets as part of healthy eating practices, with portion sizes adjusted based on age and dietary needs.

Adults: There is no specific dosage for apples; they can be consumed as part of a balanced diet. Generally, 1-2 medium apples per day is a common recommendation for health benefits.

Mechanism of action

The beneficial effects of apples are attributed to their rich content of polyphenols, flavonoids, and dietary fiber. These compounds have antioxidant properties that help reduce oxidative stress in the body, modulate lipid levels, and improve gut health by promoting the growth of beneficial gut bacteria.

Pharmacodynamics

The pharmacodynamic effects of apples are primarily linked to their ability to lower cholesterol levels, improve blood sugar control, and enhance satiety, which can contribute to weight management. The antioxidants present in apples may also play a role in reducing inflammation and preventing chronic diseases such as cardiovascular disease and certain cancers.

Pharmacokinetics

The pharmacokinetics of apples are not typically characterized in the same manner as pharmaceuticals. However, the digestion and absorption of the nutrients found in apples occur primarily in the gastrointestinal tract. Dietary fiber, particularly soluble fiber like pectin, is fermented by gut bacteria, producing short-chain fatty acids that contribute to various health benefits.

Pregnancy

Apples are generally safe to consume during pregnancy and can provide essential nutrients.

Breast-feeding

Apples are safe during breastfeeding and can be beneficial for both mother and infant.

Storage

Store apples in a cool, dry place. Refrigeration can prolong freshness.

Formulations

• whole apples
• apple juice
• apple cider
• dried apple slices

Indications

• Weight management
• Reduction of cholesterol levels
• Support in dietary fat absorption

Dosage

Children: Refer to specific product guidelines as pediatric dosages are not well established.

Adults: Refer to specific product guidelines as dosages may vary widely based on formulation and concentration.

Mechanism of action

Chitosan acts primarily through its ability to bind dietary fats and cholesterol in the gastrointestinal tract, forming a complex that is not absorbed by the body. This mechanism reduces the absorption of fats and can lead to decreased calorie intake. Additionally, it may influence lipid metabolism and promote fat excretion.

Pharmacodynamics

Chitosan exhibits a high degree of biocompatibility and is non-toxic, which allows it to be safely ingested. Its lipid-binding properties contribute to a reduction in serum cholesterol levels and may help in weight management. The effects on lipid profiles are attributed to its ability to inhibit the absorption of dietary lipids and cholesterol.

Pharmacokinetics

Chitosan is not absorbed through the gastrointestinal tract due to its high molecular weight and polymeric structure. It passes through the digestive system largely unchanged. The effects of chitosan are primarily localized to the gut, where it interacts with dietary fats and cholesterol. Its elimination is through fecal excretion.

Adverse effects

• Gastrointestinal discomfort
• Nausea
• Constipation
• Diarrhea
• Flatulence

Precautions

• Use with caution in individuals with shellfish allergies, as chitosan is derived from chitin found in shellfish.
• Monitor for gastrointestinal side effects, particularly in patients with pre-existing digestive disorders.

Pregnancy

Chitosan is generally considered safe in pregnancy, but its effects have not been extensively studied. Consultation with a healthcare provider is recommended.

Breast-feeding

Chitosan is likely safe during breastfeeding, but limited data are available. Consultation with a healthcare provider is recommended.

Storage

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

Formulations

• Capsules
• Tablets
• Powder

Indications

• Choline deficiency
• Support in liver function
• Neurological health, including cognitive function
• Fat metabolism disorders

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines.

Adults: Refer to the BNF for specific dosing guidelines.

Mechanism of action

Choline is a major component of phosphatidylcholine, which is essential for maintaining cell membrane integrity, facilitating information flow, and intracellular communication. It is involved in the synthesis of acetylcholine, a key neurotransmitter in the central nervous system. Choline deficiency can lead to apoptosis by affecting cell membrane composition and increasing ceramide levels, which activates apoptotic pathways. Additionally, choline is a precursor to betaine, which helps regulate homocysteine levels, thus reducing cardiovascular risks.

Pharmacodynamics

Choline is crucial for proper nerve conduction in the central nervous system as it is a precursor for acetylcholine. It supports liver function, gallbladder regulation, and lipid metabolism. Adequate choline levels are associated with the prevention of excessive fat accumulation in the liver and may mitigate conditions such as Parkinsonism and tardive dyskinesia. Deficiencies can lead to serious health problems, including liver dysfunction and stunted growth.

Pharmacokinetics

Choline is absorbed in the intestines and distributed throughout the body, where it is utilized in various metabolic pathways. The liver plays a central role in choline metabolism, converting it into phosphatidylcholine and other metabolites. The half-life and excretion pathways of choline are not well defined but are influenced by dietary intake, physiological state, and individual metabolism.

Interactions

• corticosteroids+cholinesalicylate: Unknown (decreases concentration)

Pregnancy

Choline is generally considered safe during pregnancy, as it is essential for fetal development, particularly for brain development and function. However, it is important to adhere to recommended dietary allowances.

Breast-feeding

Choline is important during breastfeeding as it supports infant brain development. Adequate intake is recommended for nursing mothers.

Storage

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

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.

Dosage

Children: Cider is not recommended for children or adolescents due to the potential for negative health effects

Adults: Cider is typically consumed in standard serving sizes, which can range from 330 ml to 500 ml depending on the style and alcohol content. The legal drinking age and guidelines for moderate consumption should be followed.

Mechanism of action

The primary active component in cider is ethanol, which exerts its effects primarily through the central nervous system. Ethanol enhances the effects of the neurotransmitter gamma-aminobutyric acid (GABA) at GABA-A receptors, leading to increased inhibitory neurotransmission. This results in sedation, relaxation, and a decrease in anxiety and inhibition. Ethanol also inhibits the release of neurotransmitters such as glutamate, further contributing to its depressant effects.

Pharmacodynamics

The pharmacological effects of cider, like other alcoholic beverages, are dose-dependent. At lower doses, alcohol can cause euphoria and increased sociability, while higher doses are associated with impairments in motor coordination, judgment, and memory. Chronic consumption can lead to tolerance, dependence, and various health issues, including liver disease and cardiovascular problems. The effects can vary significantly among individuals due to factors such as body weight, metabolic rate, and individual tolerance levels.

Pharmacokinetics

After consumption, ethanol is rapidly absorbed from the gastrointestinal tract, with peak blood alcohol concentrations occurring within 30 to 90 minutes. It is distributed throughout the body, penetrating various tissues, including the brain. Ethanol is primarily metabolized in the liver by the enzymes alcohol dehydrogenase and aldehyde dehydrogenase, converting it to acetaldehyde and then to acetic acid, which is further metabolized to carbon dioxide and water. The elimination half-life of ethanol varies but is generally around 1 to 2 hours, depending on the individual's metabolic capacity.

Adverse effects

• Gastrointestinal upset
• Headaches
• Allergic reactions
• Interactions with other medications

Interactions

• May interact with alcohol
• Potential interaction with medications that affect liver enzymes

Precautions

• Use with caution in individuals with liver disease
• Monitor for allergic reactions
• Assess for potential interactions with other medications

Pregnancy

Cider is generally considered safe in moderation during pregnancy, but excessive consumption should be avoided due to alcohol content.

Breast-feeding

Moderate consumption is usually considered acceptable while breastfeeding, but alcohol can pass into breast milk.

Storage

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

Formulations

• Cider beverages (alcoholic and non-alcoholic)
• Cider vinegar

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

• Hepatotoxicity prevention, particularly related to acetaminophen overdose
• Cholesterol management
• Support for hair, skin, and nail health
• Heavy metal chelation
• Kidney function support

Mechanism of action

The exact mechanism of action of L-methionine's anti-hepatotoxic activity is not fully understood. It is believed that L-methionine metabolism may counteract the depletion of hepatic glutathione caused by high doses of acetaminophen, thereby reducing oxidative stress. Additionally, L-methionine and its metabolites may exhibit free-radical scavenging activity due to the presence of sulfur, which contributes to its potential antioxidant effects. L-methionine also plays a role in protein synthesis by binding with transfer RNA (tRNA) in the cytoplasm to facilitate the translation of mRNA into proteins.

Pharmacodynamics

L-methionine serves as a primary source of sulfur, which is vital for preventing disorders affecting hair, skin, and nails. It helps lower cholesterol levels by promoting the liver's production of lecithin, reduces liver fat, and may protect the kidneys. As a natural chelating agent, it aids in the detoxification of heavy metals and influences the formation of ammonia, leading to ammonia-free urine that minimizes bladder irritation. Furthermore, it is thought to promote hair growth and exhibit antioxidant properties.

Pharmacokinetics

L-methionine is absorbed in the gastrointestinal tract and subsequently distributed throughout the body. It undergoes metabolic conversion primarily in the liver, where it is involved in various pathways, including the biosynthesis of S-adenosyl-L-methionine and the regulation of one-carbon metabolism. The elimination of L-methionine occurs through metabolic pathways and is dependent on the body's protein synthesis needs.

Adverse effects

• Gastrointestinal disturbances
• Allergic reactions
• Nausea
• Vomiting

Precautions

• Use with caution in patients with renal impairment
• Not recommended for use in patients with known hypersensitivity to methionine

Pregnancy

There is limited data on the use of L-methionine during pregnancy. Consult a healthcare provider before use.

Breast-feeding

Limited information is available. Consult a healthcare provider before use while breastfeeding.

Storage

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

Formulations

• Tablets
• Capsules
• Powder

Mechanism of action

Oxides do not have a single mechanism of action as they are a broad category of compounds. However, in general, metal oxides can exhibit catalytic properties, while non-metal oxides may participate in biochemical reactions by forming acids or bases upon dissolution in water.

Pharmacodynamics

The pharmacodynamics of oxides depend on the specific type of oxide and its interaction with biological systems. For instance, metal oxides may have antimicrobial properties, while certain non-metal oxides can influence metabolic pathways through their acid-base chemistry. The effects vary widely, necessitating specific studies for each oxide's role in therapeutic contexts.

Pharmacokinetics

The pharmacokinetics of oxides are also variable. Many metal oxides are poorly soluble and thus have limited absorption when ingested. Non-metal oxides, such as carbon dioxide, can be readily absorbed and utilized in metabolic processes. The distribution, metabolism, and excretion of oxides depend on their chemical form and the biological system in which they are involved.

Pregnancy

Not applicable as oxide is not a drug but a class of chemical compounds.

Breast-feeding

Not applicable as oxide is not a drug but a class of chemical compounds.

Storage

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

Dosage

Children: Refer to specific guidelines or consult a healthcare professional for appropriate dosing information, as current literature does not provide standardized dosing recommendations.

Adults: Refer to specific guidelines or consult a healthcare professional for appropriate dosing information, as current literature does not provide standardized dosing recommendations.

Mechanism of action

Picolinate acts as a metabolic intermediate, particularly in the catabolism of tryptophan. It participates in several biochemical pathways such as amino acid and derivative metabolism, and its presence is crucial for the degradation of tryptophan into various metabolites. This process includes its involvement in the production of important coenzymes and other bioactive compounds, thus influencing metabolic pathways and cellular functions.

Pharmacodynamics

Picolinate is involved in the metabolism of tryptophan, leading to the generation of kynurenine and other metabolites. The compound plays a role in the biosynthesis of NAD, which is essential for cellular respiration and energy production. Its effects may include modulation of metabolic pathways and potential influence on cognitive and metabolic health, although specific pharmacodynamic effects can vary based on the context of use.

Pharmacokinetics

The pharmacokinetics of picolinate, including absorption, distribution, metabolism, and excretion, are not extensively documented. It is generally understood that compounds involved in amino acid metabolism are absorbed and utilized by the body in a manner that supports metabolic functions. However, specific parameters such as bioavailability, half-life, and excretion pathways are not well-characterized.

Pregnancy

There is insufficient data on the safety of picolinate in pregnancy. Consult healthcare providers for advice.

Breast-feeding

Limited data is available on the excretion of picolinate in human milk. Caution is advised.

Storage

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

Indications

• Culinary uses
• Food preservation
• Potential antimicrobial applications
• Dietary supplement for blood glucose management

Dosage

Children: Refer to specific dietary guidelines or culinary applications as there is no standardized clinical dosing for vinegar.

Adults: Refer to specific dietary guidelines or culinary applications as there is no standardized clinical dosing for vinegar.

Mechanism of action

Acetic acid induces apoptosis in yeast cells through mechanisms that involve alterations in the target of rapamycin (TOR) pathway. This pathway is crucial for various cellular processes, including amino-acid biosynthesis, carbohydrate metabolism, and stress response. The apoptotic signaling triggered by acetic acid involves the general amino-acid control (GAAC) system, indicating that acetic acid affects protein turnover and cell cycle regulation by modulating specific protein levels and pathways.

Pharmacodynamics

The pharmacodynamics of acetic acid suggest that it influences various metabolic pathways, particularly those related to amino-acid biosynthesis and stress responses. Its ability to induce apoptosis in yeast indicates a potential for modulating cell growth and death, although the clinical significance of these effects in humans remains unclear. It may also exhibit antimicrobial activity, contributing to its use as a preservative.

Pharmacokinetics

The pharmacokinetics of acetic acid are not extensively documented in the context of clinical use. However, when ingested, acetic acid is rapidly absorbed in the gastrointestinal tract. It is metabolized primarily in the liver and may influence the metabolism of carbohydrates and fats. Due to its acidic nature, acetic acid can affect gastric pH and subsequently influence the absorption of other substances.

Pregnancy

There is insufficient data on the use of vinegar during pregnancy. Caution is advised.

Breast-feeding

Limited data exists on the effects of vinegar during breastfeeding. Consult a healthcare professional before use.

Storage

Store in a cool, dark place, tightly sealed to maintain quality.

Formulations

• Vinegar (acetic acid solution)
• Apple cider vinegar
• White vinegar
• Balsamic vinegar

Mechanism of action

Choline is a major part of the polar head group of phosphatidylcholine. Phosphatidylcholine's role in the maintenance of cell membrane integrity is vital to all of the basic biological processes: information flow, intracellular communication and bioenergetics. Inadequate choline intake would negatively affect all these processes. Choline is also a major part of another membrane phospholipid, sphingomyelin, also important for the maintenance of cell structure and function. It is noteworthy and not surprising that choline deficiency in cell culture causes apoptosis or programmed cell death. This appears to be due to abnormalities in cell membrane phosphatidylcholine content and an increase in ceramide, a precursor, as well as a metabolite, of sphingomyelin. Ceramide accumulation, which is caused by choline deficiency, appears to activate Caspase, a type of enzyme that mediates apoptosis. Betaine or trimethylglycine is derived from choline via an oxidation reaction. Betaine is one of the factors that maintains low levels of homocysteine by resynthesizing L-methionine from homocysteine. Elevated homocysteine levels are a significant risk factor for atherosclerosis, as well as other cardiovascular and neurological disorders. Acetylcholine is one of the major neurotransmitters and requires choline for its synthesis. Adequate acetylcholine levels in the brain are believed to be protective against certain types of dementia, including Alzheimer's disease.

Pharmacodynamics

This compound is needed for good nerve conduction throughout the CNS (central nervous system) as it is a precursor to acetylcholine (ACh). Choline is also needed for gallbladder regulation, liver function and lecithin (a key lipid) formation. Choline also aids in fat and cholesterol metabolism and prevents excessive fat build up in the liver. Choline has been used to mitigate the effects of Parkinsonism and tardive dyskinesia. Choline deficiencies may result in excessive build-up of fat in the liver, high blood pressure, gastric ulcers, kidney and liver dysfunction and stunted growth.

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

The mechanism of the possible anti-hepatotoxic activity of L-methionine is not entirely clear. It is thought that metabolism of high doses of acetaminophen in the liver lead to decreased levels of hepatic glutathione and increased oxidative stress. L-methionine is a precursor to L-cysteine. L-cysteine itself may have antioxidant activity. L-cysteine is also a precursor to the antioxidant glutathione. Antioxidant activity of L-methionine and metabolites of L-methionine appear to account for its possible anti-hepatotoxic activity. Recent research suggests that methionine itself has free-radical scavenging activity by virtue of its sulfur, as well as its chelating ability. Amino acids are selected for protein synthesis by binding with transfer RNA (tRNA) in the cell cytoplasm. The information on the amino acid sequence of each individual protein is contained in the sequence of nucleotides in the messenger RNA (mRNA) molecules, which are synthesized in the nucleus from regions of DNA by the process of transcription. The mRNA molecules then interact with various tRNA molecules attached to specific amino acids in the cytoplasm to synthesize the specific protein by linking together individual amino acids; this process, known as translation, is regulated by amino acids (e.g., leucine), and hormones. Which specific proteins are expressed in any particular cell and the relative rates at which the different cellular proteins are synthesized, are determined by the relative abundances of the different mRNAs and the availability of specific tRNA-amino acid combinations, and hence by the rate of transcription and the stability of the messages. From a nutritional and metabolic point of view, it is important to recognize that protein synthesis is a continuing process that takes place in most cells of the body. In a steady state, when neither net growth nor protein loss is occurring, protein synthesis is balanced by an equal amount of protein degradation. The major consequence of inadequate protein intakes, or diets low or lacking in specific indispensable amino acids relative to other amino acids (often termed limiting amino acids), is a shift in this balance so that rates of synthesis of some body proteins decrease while protein degradation continues, thus providing an endogenous source of those amino acids most in need. /Protein synthesis/ The mechanism of intracellular protein degradation, by which protein is hydrolyzed to free amino acids, is more complex and is not as well characterized at the mechanistic level as that of synthesis. A wide variety of different enzymes that are capable of splitting peptide bonds are present in cells. However, the bulk of cellular proteolysis seems to be shared between two multienzyme systems: the lysosomal and proteasomal systems. The lysosome is a membrane-enclosed vesicle inside the cell that contains a variety of proteolytic enzymes and operates mostly at acid pH. Volumes of the cytoplasm are engulfed (autophagy) and are then subjected to the action of the protease enzymes at high concentration. This system is thought to be relatively unselective in most cases, although it can also degrade specific intracellular proteins. The system is highly regulated by hormones such as insulin and glucocorticoids, and by amino acids. The second system is the ATP-dependent ubiquitin-proteasome system, which is present in the cytoplasm. The first step is to join molecules of ubiquitin, a basic 76-amino acid peptide, to lysine residues in the target protein. Several enzymes are involved in this process, which selectively targets proteins for degradation by a second component, the proteasome. /Protein degradation/ Methionine dependence, the inability of cells to grow when the amino acid methionine is replaced in culture medium by its metabolic precursor homocysteine, is characteristic of many cancer cell lines and some tumors in situ. Most cell lines proliferate normally under these conditions. The methionine dependent t

Pharmacodynamics

L-Methionine is a principle supplier of sulfur which prevents disorders of the hair, skin and nails; helps lower cholesterol levels by increasing the liver's production of lecithin; reduces liver fat and protects the kidneys; a natural chelating agent for heavy metals; regulates the formation of ammonia and creates ammonia-free urine which reduces bladder irritation; influences hair follicles and promotes hair growth. L-methionine may protect against the toxic effects of hepatotoxins, such as acetaminophen. Methionine may have antioxidant activity.

Mechanism of action

Although acetic acid has been shown to induce apoptosis in yeast, the exact apoptotic mechanisms remain unknown. Here, /the study examined/ the effects of acetic acid treatment on yeast cells by 2-DE, revealing alterations in the levels of proteins directly or indirectly linked with the target of rapamycin (TOR) pathway: amino-acid biosynthesis, transcription/translation machinery, carbohydrate metabolism, nucleotide biosynthesis, stress response, protein turnover and cell cycle. The increased levels of proteins involved in amino-acid biosynthesis presented a counteracting response to a severe intracellular amino-acid starvation induced by acetic acid. Deletion of GCN4 and GCN2 encoding key players of general amino-acid control (GAAC) system caused a higher resistance to acetic acid indicating an involvement of Gcn4p/Gcn2p in the apoptotic signaling. Involvement of the TOR pathway in acetic acid-induced apoptosis was also reflected by the higher survival rates associated to a terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-negative phenotype and lower reactive oxygen species levels of Deltator1 cells. In addition, deletion mutants for several downstream mediators of the TOR pathway revealed that apoptotic signaling involves the phosphatases Pph21p and Pph22p but not Sit4p. Altogether, /these/ results indicate that GAAC and TOR pathways (Tor1p) are involved in the signaling of acetic acid-induced apoptosis. Acetic acid was found to have actions on urinary bladder smooth muscle in /the/ routine ion channel screening assays. Numerous studies have examined the mechanisms of bladder irritation by acetic acid; however, the direct effect of acetic acid on ion channels in detrusor smooth muscle cells has not been evaluated. /The study/ used whole-cell patch-clamp techniques to examine the effect of acetic acid on large-conductance Ca2+-activated K+ channels (BKCa) from guinea pig detrusor smooth muscle cells and CHO cells expressing recombinant human BKCaalphabeta1 (CHO BKCaalphabeta1) and human BKCaalpha (CHO BKCaalpha). Acetic acid activated BKCa currents in a concentration-dependent (0.01% to 0.05% v/v) manner in all the cell systems studied. Acetic acid (0.05%) increased BKCa current at +30 mV by 2764 +/- 918% (n=8) in guinea pig detrusor smooth muscle cells. Acetic acid (0.03%) shifted the V1/2 of conductance-voltage curve by 64 +/- 14 (n=5), 128 +/- 14 (n=5), and 126 +/- 12 mV (n=4) in CHO BKCaalpha, CHO BKCaalphabeta1 and detrusor smooth muscle cells, respectively. This effect of acetic acid was found to be independent of pH and was also not produced by its salt form, sodium acetate. Automated patch-clamp experiments also showed similar activation of CHO BKCaalphabeta1 by acetic acid. In conclusion, acetic acid directly activates BKCa channels in detrusor smooth muscle cells. This novel study necessitates caution while interpreting the results from acetic acid bladder irritation model. /It was/ previously shown that acetic acid activates a mitochondria-dependent death process in Saccharomyces cerevisiae and that the ADP/ATP carrier (AAC) is required for mitochondrial outer membrane permeabilization and cytochrome c release. Mitochondrial fragmentation and degradation have also been shown in response to this death stimulus. Herein, /the study/ show that autophagy is not active in cells undergoing acetic acid-induced apoptosis and is therefore not responsible for mitochondrial degradation. Furthermore, /the study/ found that the vacuolar protease Pep4p and the AAC proteins have a role in mitochondrial degradation using yeast genetic approaches. Depletion and overexpression of Pep4p, an orthologue of human cathepsin D, delays and enhances mitochondrial degradation respectively. Moreover, Pep4p is released from the vacuole into the cytosol in response to acetic acid treatment. AAC-deleted cells also show a decrease in mitochondrial degradation in response to acetic acid and are not defective in Pep4p