RHOMO OIL

Indications

• Vitiligo
• Hyperpigmentation disorders

Dosage

Children: Refer to BNF for Children for specific dosing guidance.

Adults: Refer to BNF for specific dosing guidance.

Mechanism of action

Monobenzone acts as a depigmenting agent through an incompletely understood mechanism. It is suggested that monobenzone increases the excretion of melanin from melanocytes and interferes with the biosynthesis of melanin by inhibiting the enzyme tyrosinase. This inhibition prevents the conversion of tyrosine to dihydroxyphenylalanine, which is a precursor of melanin. As a result, the drug leads to depigmentation, especially in areas with existing hyperpigmentation, while the epidermis remains intact but lacks identifiable melanocytes.

Pharmacodynamics

Monobenzone is the monobenzyl ether of hydroquinone. It functions as a topical agent that permanently removes color from normal skin surrounding areas affected by vitiligo. By inhibiting the production of melanin, monobenzone reduces skin pigmentation and facilitates a more uniform skin tone over time. The effect is particularly pronounced in hyperpigmented skin, which fades more quickly than normal skin.

Pharmacokinetics

The pharmacokinetics of monobenzone are not extensively detailed in available literature. However, it is primarily applied topically, and its systemic absorption is likely minimal. The onset of action can vary, with effects typically observable within one to four months. The drug is metabolized within the skin, and its efficacy can be influenced by factors such as sun exposure, which can reduce its depigmenting effects.

Adverse effects

• Skin irritation
• Erythema
• Contact dermatitis
• Dry skin
• Photosensitivity

Precautions

• Avoid contact with eyes
• Not for use on broken skin
• Avoid excessive sun exposure

Pregnancy

There are no adequate and well-controlled studies in pregnant women. Use only if clearly needed.

Breast-feeding

There is no information available regarding the excretion of monobenzone in human milk. Caution should be exercised.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Topical cream
• Topical lotion

Indications

• Dry cough
• Joint pain
• Inflammation
• Gastrointestinal disturbances

Dosage

Children: Refer to BNF for Children or homeopathic guidelines for specific dosing information, as it can vary widely based on formulation and intended use.

Adults: Refer to BNF or homeopathic guidelines for specific dosing information, as it can vary widely based on formulation and intended use.

Mechanism of action

The exact mechanism of action of bryonia is not well established in conventional pharmacology. However, it is believed to modulate inflammatory pathways and may exert effects on the central nervous system to alleviate pain. Homeopathic preparations are thought to work through the principles of dilution and succussion, leading to subtle changes in biological responses.

Pharmacodynamics

Bryonia is thought to have anti-inflammatory and analgesic properties, potentially reducing pain and inflammation associated with various conditions. Its effects may lead to improvements in symptoms such as cough suppression and relief from musculoskeletal discomfort.

Pharmacokinetics

Due to the highly diluted nature of homeopathic remedies like bryonia, traditional pharmacokinetic parameters such as absorption, distribution, metabolism, and excretion are not well defined. The extreme dilutions used in homeopathy may result in minimal or negligible pharmacological activity as understood in conventional medicine.

Pregnancy

Bryonia is not recommended during pregnancy due to its potential toxicity and lack of safety data.

Breast-feeding

Bryonia is not recommended during breastfeeding due to potential adverse effects on the infant.

Storage

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

Indications

• Topical pain relief
• Muscle aches
• Joint pain
• Inflammation

Dosage

Children: For children, the

Adults: For topical application, camphor is usually applied as needed to the affected area, following the instructions on the specific product used. Consult the product label or a healthcare professional for detailed dosing guidelines.

Mechanism of action

Camphor activates the transient receptor potential vanilloid 1 (TRPV1) and TRPV3 channels, which are involved in sensing pain and temperature. It requires higher concentrations to activate TRPV1 compared to capsaicin but notably desensitizes TRPV1 more rapidly and completely. This action is enhanced under inflamed conditions through phospholipase C-coupled receptor stimulation. The distinct activation pathways of camphor contribute to its analgesic effects, making it effective in reducing pain sensitivity.

Pharmacodynamics

The pharmacodynamic properties of camphor are primarily related to its interaction with TRPV1 and TRPV3 channels. By activating these receptors, camphor induces a sensation of warmth and can result in analgesia through sensory nerve excitation and subsequent desensitization. This mechanism is similar to that of other topical analgesics like capsaicin and menthol but is characterized by a faster desensitization of TRPV1. Additionally, camphor's effects may include local vasodilation and increased blood flow to the area of application, which can further alleviate pain and inflammation.

Pharmacokinetics

Camphor is absorbed through the skin when applied topically. Its pharmacokinetic profile involves distribution to various tissues, where it can exert local effects. The metabolism of camphor occurs primarily in the liver, and it is eliminated from the body mainly through urine. The onset of action is typically rapid due to its topical application, and the duration of effect may vary depending on the formulation and concentration used.

Adverse effects

• Skin irritation
• Allergic reactions
• Nausea
• Vomiting
• Dizziness

Precautions

• Use with caution in individuals with sensitive skin
• Avoid contact with eyes and mucous membranes
• Do not apply to broken or irritated skin
• Keep out of reach of children

Pregnancy

Camphor should be used with caution during pregnancy. It is advisable to consult a healthcare professional before use.

Breast-feeding

Camphor should be used with caution while breastfeeding. Consult a healthcare professional for advice.

Storage

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

Formulations

• Topical ointments
• Liniments
• Creams
• Gels

Indications

• Topical analgesic for muscle and joint pain
• Cough suppressant in cough drops and lozenges
• Relief of minor throat irritation
• Cooling agent in various cosmetic and personal care products

Dosage

Children: Refer to BNF for Children for specific dosing guidelines, as doses may vary based on age and formulation.

Adults: For topical use, apply a thin layer to the affected area not more than 3 to 4 times daily. For cough drops, follow the product-specific instructions as per the formulation.

Mechanism of action

Menthol acts as an agonist for the transient receptor potential subtype M8 (TRPM8), a non-selective cation channel that is activated by cold temperatures. This activation leads to calcium influx in mast cells, inducing the release of histamine, which can trigger allergic responses such as urticaria, asthma, and rhinitis. Menthol's ability to induce histamine release via TRPM8 suggests potential therapeutic applications for TRPM8 antagonists in managing cold- and menthol-induced allergies.

Pharmacodynamics

Menthol produces a cooling effect by stimulating sensory neurons that convey cold sensations. It interacts with TRPM8 channels, leading to the activation of intracellular signaling pathways that can result in vasodilation and increased blood flow to the area of application. This cooling sensation can provide symptomatic relief in conditions characterized by pain or irritation.

Pharmacokinetics

Menthol is absorbed through the skin and mucous membranes, with systemic effects depending on the route of administration. Its bioavailability can vary, and it is metabolized primarily in the liver. The elimination half-life and excretion pathways have not been extensively characterized, but menthol is generally considered to have a rapid onset of action with effects lasting for a few hours.

Adverse effects

• Allergic reactions
• Urticaria
• Asthma
• Rhinitis
• Skin irritation

Precautions

• Use with caution in patients with known allergies to menthol or related compounds
• May exacerbate asthma in sensitive individuals

Pregnancy

There are no well-controlled studies of menthol in pregnant women. Menthol should be used during pregnancy only if clearly needed.

Breast-feeding

Menthol is excreted in breast milk. Caution should be exercised when administering to nursing mothers.

Storage

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

Formulations

• Topical ointment
• Cream
• Liquid

Indications

• Wound healing
• Oral health (e.g., gingivitis, mouth ulcers)
• Anti-inflammatory conditions
• Gastrointestinal disorders (e.g., dyspepsia)
• Antimicrobial applications

Dosage

Children: Refer to established herbal guidelines as specific dosing information may vary based on preparation and condition being treated.

Adults: Refer to established herbal guidelines as specific dosing information may vary based on preparation and condition being treated.

Mechanism of action

The active compounds in officinale, such as resins and essential oils, exhibit their effects through various mechanisms, including the inhibition of pro-inflammatory cytokines and modulation of immune responses. These actions contribute to its analgesic and antimicrobial properties, making it beneficial in treating wounds and oral infections.

Pharmacodynamics

Myrrh has demonstrated a range of pharmacodynamic effects, including analgesia, anti-inflammatory activity, and antimicrobial action. The resin contains various terpenoids and phenolic compounds, which interact with biological pathways to exert these effects. Studies suggest that myrrh may inhibit the growth of certain bacteria and fungi, as well as reduce inflammation by blocking the synthesis of pro-inflammatory mediators.

Pharmacokinetics

The pharmacokinetics of myrrh are not well-defined due to variability in preparation and formulation. However, it is generally believed that the compounds are absorbed through the gastrointestinal tract when ingested, with some components potentially being metabolized in the liver. The onset of action may vary depending on the method of administration, with topical applications likely providing localized effects.

Pregnancy

Safety during pregnancy has not been established; consult a healthcare provider before use.

Breast-feeding

Consult a healthcare provider before using, as safety during breastfeeding is not well established.

Storage

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

Dosage

Children: Oleum is not used for therapeutic dosing in children.

Adults: Oleum is not used for therapeutic dosing in adults.

Mechanism of action

Oleum acts primarily as a strong acid and dehydrating agent. Upon contact with water, it forms sulfuric acid, which dissociates to release protons (H+), leading to acidification. The presence of sulfur trioxide enhances its reactivity, enabling it to sulfonate organic compounds, thus modifying their chemical properties and reactivity.

Pharmacodynamics

Oleum's pharmacodynamics are rooted in its ability to react with water and organic substrates. The release of protons contributes to its acidic properties, while the sulfonation process allows it to interact with biomolecules, potentially altering their function. However, oleum is not used therapeutically due to its extreme toxicity and corrosiveness.

Pharmacokinetics

Oleum does not have a pharmacokinetic profile as it is not administered as a drug for therapeutic purposes. Its use is limited to industrial applications, and it is handled with extreme caution due to its corrosive nature. Exposure can occur via inhalation, dermal contact, or ingestion, leading to severe chemical burns and respiratory damage.

Pregnancy

There is limited information on the safety of oleum during pregnancy. It should be used only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Due to insufficient data, the use of oleum during breastfeeding should be approached with caution. Weigh the risks and benefits before use.

Storage

Store in a cool, dry place away from direct sunlight and moisture. Ensure containers are tightly sealed to prevent contamination.

Indications

• Contact dermatitis
• Allergic reactions to urushiol
• Inflammatory skin conditions

Dosage

Children: Specific pediatric dosing for Rhus is not established. Consult relevant guidelines for management of allergic reactions in children.

Adults: Dosage for Rhus is not typically established in conventional medicine due to its nature as a plant extract. For management of allergic reactions, supportive care and antihistamines are recommended.

Mechanism of action

The primary active component, urushiol, binds to skin proteins, modifying them and creating a hapten-protein complex. This complex elicits an immune response, leading to delayed-type hypersensitivity reactions, characterized by inflammation, redness, and itching. The immune response is mediated by T-lymphocytes, which recognize the modified proteins as foreign.

Pharmacodynamics

Rhus exhibits anti-inflammatory effects, primarily through the modulation of cytokine release and immune cell activity. However, in sensitive individuals, it can provoke severe inflammatory responses, resulting in contact dermatitis. The severity of the reaction depends on individual sensitivity and the amount of urushiol exposure.

Pharmacokinetics

The absorption of urushiol occurs primarily through the skin upon contact. Once absorbed, it induces a localized immune response. The systemic absorption is minimal, but in cases of extensive exposure, it may enter the bloodstream, potentially leading to widespread allergic reactions. The elimination of urushiol is not well characterized, but it is believed to be metabolized in the liver and excreted via urine, with a half-life that is variable based on the extent of exposure and individual factors.

Pregnancy

Rhus species, particularly those containing toxic components, should be used with caution during pregnancy due to the potential for adverse effects on fetal development. It is best to avoid use unless specifically prescribed by a healthcare professional.

Breast-feeding

Caution is advised when using Rhus products while breastfeeding, as there is limited information on the safety and effects of these substances in nursing infants.

Storage

Store in a cool, dry place away from direct sunlight. Ensure that products are kept out of reach of children.

Indications

• Topical treatment of minor wounds
• Bruises
• Sprains
• Fractures
• Skin irritations

Dosage

Children: Refer to the BNF for Children for appropriate dosing and guidance on the use of comfrey in paediatric populations.

Adults: For topical use, apply a comfrey ointment or cream to the affected area as needed, but avoid prolonged use to reduce the risk of adverse effects.

Mechanism of action

The primary active compound in Symphytum, allantoin, is thought to support wound healing and tissue repair by promoting cell proliferation and differentiation. Allantoin may also have anti-inflammatory properties, contributing to the reduction of swelling and pain in injured tissues. Additionally, the mucilage content in comfrey may help soothe irritated tissues when applied topically.

Pharmacodynamics

Symphytum exhibits properties that may assist in the healing of damaged tissues, likely due to the presence of allantoin and other phytochemicals. The anti-inflammatory effects may reduce pain and swelling, while the regenerative effects could enhance tissue repair processes. However, the full pharmacodynamic profile remains less understood and requires further research.

Pharmacokinetics

The pharmacokinetics of Symphytum have not been extensively studied. Generally, topical applications of comfrey extract allow for local effects with minimal systemic absorption. When used as an oral supplement, there are concerns regarding potential hepatotoxicity, which necessitates caution and careful consideration of dosing and duration of use.

Contra-indications

• Hypersensitivity to symphytum or its components
• Active liver disease

Adverse effects

• Skin irritation
• Gastrointestinal disturbances
• Allergic reactions

Interactions

• May enhance the effects of anticoagulant medications due to potential liver enzyme interactions
• May interact with other hepatotoxic drugs

Precautions

• Use with caution in patients with liver disorders
• Monitor for any signs of hepatotoxicity
• Avoid prolonged use

Pregnancy

Safety during pregnancy has not been established. Use only if clearly needed and after assessing risks and benefits.

Breast-feeding

Not recommended due to potential risks to the infant.

Storage

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

Formulations

• Topical creams
• Ointments
• Tinctures
• Dried herb for infusion

Indications

• Muscle pain
• Joint pain
• Respiratory congestion
• Cough

Dosage

Children: For paediatric use, refer to specific formulations and guidelines, as dosing may vary significantly based on age, weight, and condition being treated.

Adults: Dosage varies widely based on formulation and route. It is important to refer to specific product guidelines or consult a healthcare professional for appropriate dosing information.

Mechanism of action

Terebinthena exerts its effects through multiple mechanisms, including the stimulation of mucous secretions in the respiratory tract, which aids in expectoration. Additionally, it may have mild analgesic properties that help alleviate pain when applied topically due to its irritant effects on the skin, leading to increased blood flow and localized warmth.

Pharmacodynamics

The pharmacodynamic effects of terebinthena primarily relate to its irritant and stimulant properties. When applied topically, it can induce local inflammation, which may promote healing and pain relief in underlying tissues. In the respiratory system, terebinthena may help reduce viscosity of mucus, facilitating easier expulsion and improving respiratory function.

Pharmacokinetics

Terebinthena is absorbed through the skin and mucous membranes, with systemic effects possible depending on the route of administration. Metabolism primarily occurs in the liver, where it is converted into various metabolites. Excretion of terebinthena and its metabolites occurs mainly via the kidneys, with a variable half-life depending on the individual’s metabolism and the formulation used.

Contra-indications

• Hypersensitivity to terebinthina or any of its components
• Severe renal impairment
• Active liver disease

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Abdominal pain
• Skin irritation
• Allergic reactions including rash and pruritus
• Dizziness
• Headache

Interactions

• May enhance the effects of anticoagulants, increasing the risk of bleeding
• Possible interaction with other hepatotoxic drugs, increasing the risk of liver toxicity
• Caution when used with other medications that affect liver enzymes

Precautions

• Use with caution in patients with a history of liver disease
• Monitor for signs of allergic reactions
• Caution in patients with gastrointestinal disorders

Pregnancy

Safety in pregnancy has not been established. Use only if potential benefits justify the potential risks to the fetus.

Breast-feeding

It is unknown if terebinthina is excreted in human breast milk. Caution is advised when administering to nursing women.

Storage

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

Formulations

• Topical ointment
• Liquid solution

Indications

• Immunological disorders
• Infections (bacterial and fungal)
• Inflammatory conditions

Dosage

Children: Refer to BNF for Children for specific dosages pertinent to paediatric patients.

Adults: Refer to BNF for specific dosages, as they can vary based on indication and formulation.

Mechanism of action

Thymol modulates macrophage activity by enhancing phagocytosis and increasing the proliferation of splenocytes, acting as a mitogen. It improves macrophage uptake capacity through increased membrane fluidity and enhances lysosomal activity. Thymol also stimulates the respiratory burst in macrophages, leading to increased generation of superoxide anions. Additionally, it shows anti-inflammatory effects by decreasing the secretion of pro-inflammatory cytokines such as TNF-alpha, IL-1beta, and PGE(2).

Pharmacodynamics

Thymol exhibits various pharmacodynamic effects including antimicrobial, antifungal, and immunomodulatory activities. Its ability to enhance macrophage function suggests a role in boosting the immune response, potentially benefiting conditions characterized by immune dysfunction. The compound also demonstrates antioxidant properties, contributing to its anti-inflammatory effects.

Pharmacokinetics

The pharmacokinetic profile of thymol is not fully characterized; however, it is known to be readily absorbed and distributed in the body due to its lipophilic nature. Metabolism occurs in the liver, with excretion primarily through the urine. The exact half-life and elimination pathways require further investigation to provide a comprehensive overview.

Pregnancy

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

Breast-feeding

Limited information is available regarding the excretion of thymol in human milk. Caution is recommended.

Storage

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

Indications

• Contact dermatitis due to exposure to poison ivy, poison oak, or poison sumac
• Management of allergic skin reactions

Dosage

Children: For children, treatment approaches are similar to adults, but dosing for medications should be based on age and weight. Refer to pediatric dosing guidelines or consult a healthcare provider.

Adults: Treatment typically involves topical corticosteroids, oral antihistamines, and soothing lotions. Dosage should be guided by clinical judgment and specific product instructions.

Mechanism of action

Urushiol, the active compound in Toxicodendron, binds to skin proteins, modifying them and triggering an immune response. This results in the activation of T cells, which leads to an inflammatory response in sensitized individuals. The immune response is characterized by the activation of CD4+ T-helper cells and the recruitment of additional inflammatory cells to the site of exposure.

Pharmacodynamics

The allergic reaction induced by urushiol typically manifests within 12 to 48 hours after exposure, peaking at about 24 to 72 hours. Symptoms include erythema, edema, and vesicle formation. The severity of the reaction can be influenced by factors such as previous sensitization, dose of urushiol, and individual immune response.

Pharmacokinetics

Urushiol is not systemically absorbed through intact skin; however, when applied to damaged skin or through mucous membranes, it can enter the bloodstream. The half-life of urushiol in the body is not well characterized, as it primarily exerts its effects locally on the skin. The compound is metabolized by the liver and is excreted through bile and urine.

Adverse effects

• Skin irritation
• Allergic contact dermatitis
• Rash
• Itching
• Erythema

Precautions

• Avoid contact with skin and mucous membranes
• Wash hands thoroughly after handling
• Use protective clothing when handling

Pregnancy

Safety during pregnancy has not been established. Use with caution.

Breast-feeding

Safety during breastfeeding has not been established. Use with caution.

Storage

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

Formulations

• Topical preparations
• Ointments
• Creams

Mechanism of action

Monobenzone is a depigmenting agent whose mechanism of action is not fully understood. It is proposed that it increases the excretion of melanin from the melanocytes. This effect is erratic and may take one to four months to occur while existing melanin is lost with normal sloughing of the stratum corneum. Hyperpigmented skin appears to fade more rapidly than does normal skin, and exposure to sunlight reduces the depigmenting effect of the drug. Following skin depigmentation after topical application of monobenzone, the histological studies indicate similar results as that seen in vitiligo, where the epidermis is intact but with the absence of identifiable melanocytes. ...INTERFERES WITH BIOSYNTHESIS OF MELANIN. IT INHIBITS ENZYME TYROSINASE & THEREBY PREVENTS CONVERSION OF TYROSINE TO DIHYDROXYPHENYLALANINE, PRECURSOR OF MELANIN.

Pharmacodynamics

Monobenzone is the monobenzyl ether of hydroquinone. Monobenzone, applied topically to the skin, is used as a depigmenting agent inhibitting melanin produced by polymerization of oxidation products of tyrosine and dihydroxyphenyl compounds. Monobenzone works by permanently removing color from normal skin located around skin with vitiligo.

Mechanism of action

Camphor is a naturally occurring compound that is used as a major active ingredient of balms and liniments supplied as topical analgesics. ... Capsaicin and menthol, two other topically applied agents widely used for similar purposes, are known to excite and desensitize sensory nerves by acting on two members of transient receptor potential (TRP) channel superfamily: heat-sensitive TRP vanilloid subtype 1 (TRPV1) and cold-sensitive TRP channel M8, respectively. Camphor has recently been shown to activate TRPV3, and here /investigators/ show that camphor also activates heterologously expressed TRPV1, requiring higher concentrations than capsaicin. Activation was enhanced by phospholipase C-coupled receptor stimulation mimicking inflamed conditions. Similar camphor-activated TRPV1-like currents were observed in isolated rat DRG neurons and were strongly potentiated after activation of protein kinase C with phorbol-12-myristate-13-acetate. Camphor activation of rat TRPV1 was mediated by distinct channel regions from capsaicin, as indicated by camphor activation in the presence of the competitive inhibitor capsazepine and in a capsaicin-insensitive point mutant. Camphor did not activate the capsaicin-insensitive chicken TRPV1. TRPV1 desensitization is believed to contribute to the analgesic actions of capsaicin. /The authors/ found that, although camphor activates TRPV1 less effectively, camphor application desensitized TRPV1 more rapidly and completely than capsaicin. Conversely, TRPV3 current sensitized after repeated camphor applications, which is inconsistent with the analgesic role of camphor. /Investigators/ also found that camphor inhibited several other related TRP channels, including ankyrin-repeat TRP 1 (TRPA1). The camphor-induced desensitization of TRPV1 and block of TRPA1 may underlie the analgesic effects of camphor.

Mechanism of action

Exposure to low temperatures often causes allergic responses or urticaria. Similarly, menthol, a common food additive is also known to cause urticaria, asthma, and rhinitis. However, despite the obvious clinical implications, the molecular mechanisms responsible for inducing allergic responses to low temperatures and menthol have not been determined. Because a non-selective cation channel, transient receptor potential subtype M8 (TRPM8) is activated by cold and menthol, we hypothesized that this channel mediates cold- and menthol-induced histamine release in mast cells. Here, we report that TRPM8 is expressed in the basophilic leukemia mast cell line, RBL-2H3, and that exposure to menthol or low temperatures induced Ca(2+) influx in RBL-2H3 cells, which was reversed by a TRPM8 blocker. Furthermore, menthol, a TRPM8 agonist, induced the dose-dependent release of histamine from RBL-2H3 cells. When TRPM8 transcripts were reduced by siRNA (small interfering RNA), menthol- and cold-induced Ca(2+) influx and histamine release were significantly reduced. In addition, subcutaneous injection of menthol evoked scratching, a typical histamine-induced response which was reversed by a TRPM8 blocker. Thus, our findings indicate that TRPM8 mediates the menthol- and cold-induced allergic responses of mast cells, and suggest that TRPM8 antagonists be viewed as potential treatments for cold- and menthol-induced allergies. /DL-Menthol/ Menthol's characteristic cooling sensation is due, in part, to the activation of sensory neurons generally termed transient receptor potential (TRP) channels, in particular transient receptor potential melastatin family member 8 (TRPM8) and transient receptor potential subfamily A, member 1 (TRPA1). Menthol acts upon TRPM8 receptors by rapidly increasing intracellular calcium and mobilizing calcium flux through the channels to induce cold response signals at the application site. Aside from its cold-inducing sensation capabilities, menthol exhibits cytotoxic effects in cancer cells, induces reduction in malignant cell growth, and engages in synergistic excitation of GABA receptors and sodium ion channels resulting in analgesia. /DL-Menthol/ In recent years, the transient receptor potential melastatin member 8 (TRPM8) channel has emerged as a promising prognostic marker and putative therapeutic target in prostate cancer. We have found that forced overexpression of TRPM8 in PC-3 cells can inhibit the cell proliferation and motility probably through the TRPM8 activation. In this study, we aimed to investigate whether activating the TRPM8 channel by its selective agonist menthol can inhibit the proliferation and motility of androgen-independent prostate cancer (AIPC) with remarkable expression of TRPM8. Menthol is a naturally occurring compound, which has been widely used in cosmetics and pharmaceutical products, and also as flavoring in food. DU145 cells are androgen-independent but have a remarkable expression of TRPM8. The demonstration of the existence of TRPM8 and the absence of TRPA1 in DU145 cells provided the foundation for the following experiments, because both TRPM8 and TRPA1 are molecular targets of menthol. The outcome of MTT assay indicated that menthol inhibited the cell growth (p < 0.01). Cell cycle distribution and scratch assay analysis revealed that menthol induced cell cycle arrest at the G(0)/G(1) phase (p < 0.01). Furthermore, menthol inhibited the migration of DU145 cells by downregulating the focal-adhesion kinase. So it suggests that the activation of the existing TRPM8 channels may serve as a potential and pragmatic treatment for those AIPC with remarkable expression of TRPM8, and menthol is a useful compound for future development as an anticancer agent. /DL-Menthol/

Mechanism of action

The potent role of thymol, a natural compound, in modulation of macrophage activity was evaluated by determining all the sequential steps involved during phagocytosis. We found a significant increase in the proliferation of splenocytes in the presence of thymol and it proved to be a good mitogen. Uptake capacity of macrophages was enhanced due to increased membrane fluidity after treatment with thymol and it also increases lysosomal activity of macrophages. Data of superoxide anion generation revealed the involvement of thymol in the generation of respiratory burst as it potentiated this property of macrophages at a concentration of 150 uM. In the case of TNF-a, IL-1beta and PGE(2) a decreased level of secretion was observed 154 pg/mL, 736.1 pg/mL, and 151 pg/mL respectively when compared with lipopolysaccharide treated cells, where the level of these cytokines was significantly high. We also determined the anti-complementary activity of thymol which showed to be more effective than rosmarinic acid. Thus, the results obtained from the study suggest the potential role of thymol as a natural immunostimulatory drug which can be used in the treatment of various immunological disorders.