Shikonin

1.373 g/cu cm

White or slightly yellow crystalline powder

Practically insoluble in aqueous solutions

147 °C

Warning

H302+H312+H332 (50%): Harmful if swallowed, in contact with skin or if inhaled [Warning Acute toxicity, oral; acute toxicity, dermal; acute toxicity, inhalation]；H412 (50%): Harmful to aquatic life with long lasting effects [Hazardous to the aquatic environment, long-term hazard]

P261, P264, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P317, P321, P330, P362+P364, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 2 reports by companies from 2 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.；Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website.

Not flammable or combustible.

Hazardous decomposition products formed under fire conditions. Carbon oxides.

Aquatic Chronic 3 (50%)

Extinguishing Media: Carbon dioxide, dry chemical powder, polymer foam, water spray.

Special Firefighting Procedures: Use self-contained breathing apparatus and protective clothing to prevent contact with skin and eyes.

Keep container tightly closed in a dry and well-ventilated place. Recommended storage temperature: 2-8 °C. Store with desiccant.

... Store at room temperature. It should be kept in a tightly closed container.

For spill clean up, wear suitable protective clothing, chemical resistant rubber gloves, rubber boots, and chemical safety goggles. Self contained breathing apparatus or NIOSH/MSHA approved respirator is required.

... Wipe up spill and place in sealed container and hold for disposal. Avoid raising dust. Ventilate the area and wash spill site after material has been removed.

SRP: Criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

SRP: Wastewater from contaminant suppression, cleaning of protective clothing/equipment, or contaminated sites should be contained and evaluated for subject chemical or decomposition product concentrations. Concentrations shall be lower than applicable environmental discharge or disposal criteria. Alternatively, pretreatment and/or discharge to a permitted wastewater treatment facility is acceptable only after review by the governing authority and assurance that "pass through" violations will not occur. Due consideration shall be given to remediation worker exposure (inhalation, dermal and ingestion) as well as fate during treatment, transfer and disposal. If it is not practicable to manage the chemical in this fashion, it must be evaluated in accordance with EPA 40 CFR Part 261, specifically Subpart B, in order to determine the appropriate local, state and federal requirements for disposal.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. The completeness of the cleaning procedures should be considered before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at the end of shift, but should remain at employee's place of work for cleaning.

Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

Personal protective equipment: Respiratory protection: For nuisance exposures use type P95 (US) or type P1 (EU EN 143) particle respirator. For higher level protection use type OV/AG/P99 (US) or type ABEK-P2 (EU EN 143) respirator cartridges. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU). Hand protection: Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands. Eye protection: Safety glasses with side-shields conforming to EN166 Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU). Skin and body protection: Complete suit protecting against chemicals, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.

...Wear suitable protective clothing, chemical resistant rubber gloves, rubber boots, and chemical safety goggles. Self contained breathing apparatus or NIOSH/MSHA approved respirator is required.

For spill clean up, wear suitable protective clothing, chemical resistant rubber gloves, rubber boots, and chemical safety goggles. Self contained breathing apparatus or NIOSH/MSHA approved respirator is required.

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1800(SRC), determined from a structure estimation method(2), indicates that shikonin is expected to have low mobility in soil(SRC). Volatilization of shikonin from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 8.3X10-15 atm-cu m/mole(SRC), using a fragment constant estimation method(2). Shikonin is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 5.1X10-11 mm Hg at 25 °C(SRC) determined from a fragment constant method(2). Shikonin absorbs UV light at wavelengths >290 nm(3) and, therefore, may be susceptible to direct photolysis on soil surfaces exposed to sunlight(SRC).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1800(SRC), determined from a structure estimation method(2), indicates that shikonin is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 8.3X10-15 atm-cu m/mole(SRC) developed using a fragment constant estimation method(2). Phenols can undergo sensitized photo-oxidation in surface waters exposed to sunlight via reaction with hydroxyl and RO2 radicals with half-lives on the order of days to weeks at the water surface(4); therefore, photo-oxidation may be an important fate process for shikonin in natural water(SRC). Shikonin is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(3). According to a classification scheme(5), an estimated BCF of 15(SRC), from an estimated log Kow of 3.56(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), shikonin, which has an estimated vapor pressure of 5.1X10-11 mm Hg at 25 °C(SRC), determined from a fragment constant method(2), is expected to exist solely in the particulate phase in the ambient atmosphere. Particulate-phase Shikonin may be removed from the air by wet and dry deposition(SRC).

Shikonin is found in the herb Lithospermum erythrorhizon(1).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of shikonin can be estimated to be 1800(SRC). According to a classification scheme(2), this estimated Koc value suggests that shikonin is expected to have low mobility in soil.

Shikonin occurs as an acetyl derivative in the Japanese plant shikone, Lithospermum erythrorhizon, a member of the Boraginaceae family(1). Shikonin is found in the herb Lithospermum erythrorhizon(2). Shikonin is isolated from Chinese medicine Zi Cao (gromwell), the dried root of Lithospermum erythrorhizon Sieb. et Zucc, Arnebia euchroma (Royle) Johnst, or Arnebia guttata(3).

/ALTERNATIVE and IN VITRO TESTS/ Shikonin has the potential to prevent, or be used in the treatment of bladder transitional cell carcinoma induced by arylamines. /Investigators/ evaluated its effectiveness by measuring the amount of acetylated 2-aminofluorene (AF), AF-DNA adducts, changes of / N-acetyltransferase (NAT)/ mRNA and the amount of NAT enzyme. T24 human bladder cancer cells were incubated with 30 uM AF with different concentrations of shikonin for various times. T24 cells treated with shikonin (16 uM) were then harvested and used in 2 experiments: 1). T24 cells were incubated with 22.5 uM AF and shikonin (0, 16 uM) (co-treatment) for 6, 12, 18, 24 and 48 hr). T24 cells were incubated with various concentrations of AF and shikonin (0, 16 uM) for 24 hr AF and AAF were measured by HPLC. Then in the prepared human T24 cell cytosols different concentrations of AF and shikonin were added to measure the kinetic constants of NAT. Next, AF-DNA adducts in human T24 cells with or without treatment with shikonin were detected and measured. The final two steps included measuring the NAT Ag-Ab complex after treatment with and without shikonin and evaluating the effect of shikonin on the NAT genes. Higher concentrations of shikonin induced decreasing AF acetylation. /It was/ found that the longer the culture period, the greater the difference in AF acetylation in the same shikonin concentrations. It was also noted that increase in AAF was proportional to incubation time. In the presence of 16 uM of shikonin, N-acetylation of AF decreased by up to 72-84%. Shikonin decreased the amount of AAF production in human T24 cells in all examined AF doses. Both Km and Vmax values in the cytosolic NAT decreased after the addition of shikonin to the cytosol. Finally, shikonin decreased the amount of AAF production and AF-DNA adducts formation in human 724 cells in all examined AF doses. The percentage of cells stained by antibody was significantly different after treatment with shik

/ALTERNATIVE and IN VITRO TESTS/ Shikonin isolated from the roots of the Chinese herb Lithospermum erythrorhizon has been associated with anti-inflammatory properties. /Investigators/ evaluated shikonin's chemotherapeutic potential and investigated its possible mechanism of action in a human cutaneous neoplasm in tissue culture. Shikonin preferentially inhibits the growth of human epidermoid carcinoma cells concentration- and time-dependently compared to SV-40 transfected keratinocytes, demonstrating its anti-proliferative effects against this cancer cell line. Additionally, shikonin decreased phosphorylated levels of EGFR, ERK1/2 and protein tyrosine kinases, while increasing phosphorylated JNK1/2 levels. Overall, shikonin treatment was associated with increased intracellular levels of phosphorylated apoptosis-related proteins, and decreased levels of proteins associated with proliferation in human epidermoid carcinoma cells.

/ALTERNATIVE and IN VITRO TESTS/ This study investigated the potential of shikonin as an anticancer agent against liver cancer and an in vitro human hepatoma cancer model system. The HepG2 cell line was the hepatoma cancer model in the present study. The inhibitory effect of shikonin on the growth of HepG2 cells was measured by MTT assay. To explore the underlying mechanism of cell growth inhibition of shikonin, the cell cycle distribution, DNA fragmentation, mitochondrial membrane potential disruption, and expression of Bax and Bcl-2 were measured in HepG2 cells. The activity of shikonin in inducing apoptosis was investigated through the detection of Annexin V signal and CD95 expression by flow cytometry and electron microscopy, respectively. Shikonin inhibited the growth of HepG2 cells in a dose-dependent manner. The IC50 value (inhibiting cell growth by 50%) was 4.30 mg/mL. Shikonin inhibited cell growth in a dose-dependent manner and blocked HepG2 cell cycle progression at the S phase. The changes in mitochondrial morphology, dose-dependently decreased in mitochondrial membrane potential, were observed in different concentrations of the drug treatment group. Western blot analysis showed that cajanol inhibited Bcl-2 expression and induced Bax expression. ...shikonin increases Annexin V signal and CD95 (Fas/APO) expression, resulting in apoptotic cell death of HepG2 cells. In addition, lump formation of intranuclear chromatin, pyknosis of cell nucleus, deletion of microvillus, vacuolar degeneration of mitochondria, reduction of rough endoplasmic reticulum, and resolution of free ribosome, etc., associated with apoptosis were discovered by electron microscopy in HepG2 cells after 48 hr treatment. Shikonin inhibited HepG2 cells, possibly through the pathway of inducing early apoptosis, and was beneficial for restoring the apoptotic sensitivity of HepG2 cells by CD95, and should therefore be considered as a candidate agent for the prevention or treatment of human hep

/ALTERNATIVE and IN VITRO TESTS/ Shikonin (SK) has been isolated and identified as a key bioactive component in an herbal plant, Shikon (gromwell). /This study/ investigated antiestrogen activity of SK in breast cancer cells /MCF-7, T47D and MDA-MB-231 cells/. In human breast cancer cells, we observed that treatment with SK inhibits tumor cell growth in estrogen receptor alpha (ERalpha)-positive, but not ERalpha-negative breast cancer cells. Estrogen-dependent cell growth was inhibited by co-treatment with SK. A potential molecular mechanism by which SK inhibits estrogen action was explored... SK has no effect on ERalpha mRNA expression, but decreases its protein level. This effect is associated with an increase in ubiquitinated ERalpha for degradation. /The/ results suggest that SK downregulates ERalpha protein through a proteasome-mediated pathway. ...treatment with SK inhibits estrogen-induced estrogen response elements reporter gene activity. Furthermore, SK inhibits recruitment of ERalpha at the estrogen-dependent gene promoters, and subsequently suppresses gene expression. Finally, co-treatment with SK enhanced sensitivity of breast cancer cells to endocrine therapy...

For more Human Toxicity Excerpts (Complete) data for Shikonin (11 total), please visit the HSDB record page.

Shikonin's production and use as a mordant dye for fabrics and cosmetics(1) may result in its release to the environment through various waste streams(SRC).

An estimated BCF of 15 was calculated in fish for shikonin(SRC), using an estimated log Kow of 3.56(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

The Henry's Law constant for shikonin is estimated as 8.3X10-15 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that shikonin is expected to be essentially nonvolatile from water surfaces(2). Shikonin's Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Shikonin is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 5.1X10-11 mm Hg(SRC) determined from a fragment constant method(1).

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ /The objective of this study was / to investigate the anti-inflammatory or immunomodulatory effect of shikonin on early stage and established murine collagen-induced arthritis (CIA). /Mice/ were injected intraperitoneally with shikonin (5 mg/kg) for 10 days along, before, or after the onset of CIA. The arthritis response was monitored visually by macroscopic scoring. Reverse transcription-polymerase chain reaction and western blotting were employed to determine the mRNA and protein expression of cytokine in patella with adjacent synovium in CIA /mice/. Histology of knee was used to assess the occurrence of cartilage destruction and bone erosion. Shikonin (5 mg/kg) treatment along had no effect on macroscopic score and incidence of arthritis on early stage of CIA. However, a pronounced amelioration of macroscopic score and cartilage destruction was found in mouse treated with shikonin on established CIA for 10 days. Moreover, The mRNA levels of Th1 cytokines [tumor necrosis factor-alpha and interleukin (IL)-12] was significantly inhibited both in the synovial tissue and in the articular cartilage in treated groups compared with those in control groups, whereas the mRNA and protein levels of Th2 cytokines (IL-10 and IL-4) remained elevated throughout the treatment period. Moreover, the inflammatory cytokine, the mRNA and protein levels of IL-6 were down-regulated in mice with established CIA after treatment with shikonin. T-box expressed in T cells (T-bet) mRNA levels were decreased in shikonin compared with control group, and GATA-3 mRNA levels were higher than that in control group. Shikonin treatment on established CIA can inhibit Th1 cytokines expression and induce Th2 cytokines expression in mice with established CIA. The inhibited effect of shikonin on Th1 cytokines expression may be mediated not only by inhibiting Th1 responses through T-bet mechanism, but also by inducing anti-inflammatory mediators suc

/LABORATORY ANIMALS: Subchronic or Prechronic Exposure/ The present study was performed to evaluate the potential protective effects of Shikonin extracted from Zicao on lupus nephritis (LN) using NZB/W F1 mice. Oral administration of Shikonin (24, 40 mg/kg body weight/d) or vehicle was applied to sixty female NZB/W F1 mice of 28-week-old with LN. Treatment with Shikonin for 14 weeks suppressed proteinuria dose-dependently with the mean proteinuria of 274.0 mg/dL and 160.3 mg/dL for low-dose and high-dose Shikonin groups, respectively, compared to 499.2 mg/dL for the vehicle. Also, Shikonin was observed to reduce circulating adhesion molecules significantly and down-regulate intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) mRNA expression in kidney. However, anti-double stranded (ds) DNA antibody in mice with low or high Shikonin dose administration both exhibited no significant elevation, differing from vehicle group. Kidney histological examination showed that renal glomerular lesions were alleviated after Shikonin application...

/LABORATORY ANIMALS: Neurotoxicity/ The aim of /this/ study was to investigate the neuroprotective properties of shikonin, a naphthoquinone pigment isolated from the roots of the traditional Chinese herb Lithospermum erythrorhizon. In the present study, mice were divided randomly into sham, model, shikonin and edaravone-treated groups. Shikonin (50, 25, and 12.5mg/kg, i.g.) or maize oil was administered three times before ischemia and once at 2 hr after the onset of ischemia. Mice were anesthetized with chloral hydrate and subjected to middle cerebral artery 2h of occlusion and then 22 hr of reperfusion. Different antioxidant assays were employed in order to evaluate the antioxidant activities of shikonin in vitro. Neurological deficit, infarct size, histopathology changes and oxidative stress markers were evaluated after 22 hr of reperfusion. In comparison with the model group, treatment with shikonin significantly decreased neurological deficit scores, infarct size, the levels of malondialdehyde(MDA), carbonyl and reactive oxygen species, and attenuated neuronal damage, up-regulated superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) activities and reduced glutathione (GSH)/glutathione disulfide (GSSG) ratio. Taken together, these results suggested that the neuroprotective effects of shikonin against cerebral ischemia/reperfusion injury may be attributed to its antioxidant effects.

/LABORATORY ANIMALS: Neurotoxicity/ Microglial cells are the prime effectors in immune and inflammatory responses of the central nervous system (CNS). During pathological conditions, the activation of these cells helps restore CNS homeostasis. However, chronic microglial activation endangers neuronal survival through the release of various proinflammatory molecules and neurotoxins. Thus, negative regulators of microglial activation have been considered as potential therapeutic candidates to target neurodegeneration, such as that in Alzheimer's and Parkinson's diseases. Shikonin, a naphthoquinone pigment from the root of Lithospermum erythrorhizon, has long been used as an ointment for wound healing in traditional oriental medicine. Shikonin has been reported to have antibacterial, antitumor, and anti-inflammatory effects. The aim of this study was to examine whether shikonin represses microglial activation. In a study of shikonin and five of its derivatives, isobutyrylshikonin (IBS) and isovalerylshikonin (IVS) were the most effective at inhibiting LPS-induced nitric oxide (NO) release from microglial cells. Reverse transcriptase real-time PCR analysis revealed that pretreatment of rat brain microglia with IBS and IVS attenuated the LPS-induced expression of mRNAs encoding inducible NO synthase, tumor necrosis factor (TNF)-alpha, interleukin-1beta, and cyclooxygenase-2. In rat brain microglia, IBS and IVS reduced the LPS-stimulated production of TNF-alpha and prostaglandin E2. In addition, IBS and IVS significantly decreased LPS-induced IkappaB-alpha phosphorylation and NF-kappaB DNA binding activity, as well as the phosphorylation of the ERK1/2 and Akt signaling proteins. In organotypic hippocampal slice cultures, propidium iodide staining revealed prominent cell death in the hippocampal layer after 72 hr of LPS treatment. Both IBS and IVS clearly blocked the effect of LPS on hippocampal cell death and inhibited LPS-induced NO production in culture medium. These re

For more Non-Human Toxicity Excerpts (Complete) data for Shikonin (24 total), please visit the HSDB record page.

The rate constant for the vapor-phase reaction of shikonin with photochemically-produced hydroxyl radicals has been estimated as 1.2X10-10 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 3 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). Shikonin is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions(2). Shikonin does contain chromophores that absorb at wavelengths >290 nm(2) and has an absorbance maximum at 518 nm(3); therefore, it may be susceptible to direct photolysis by sunlight(SRC). Phenols can undergo sensitized photo-oxidation in surface waters exposed to sunlight via reaction with hydroxyl and RO2 radicals with half-lives on the order of days to weeks at the water surface(4); therefore, photo-oxidation may be an important fate process for shikonin in natural water(SRC).

Occupational exposure to shikonin may occur through dermal contact with this compound at workplaces where shikonin is produced or used. The general population can be exposed to shikonin via ingestion of herbal medicines containing the compound and dermal contact with consumer products, such as cosmetics, containing shikonin or fabrics dyed with shikonin. (SRC)

Shikonin is a component of Chinese herbal medicine(1).

/Investigators/ previously developed a gene-gun-based in vivo screening system and identified shikonin as a potent suppressor of tumor necrosis factor-alpha (TNF-alpha) gene expression. Here... shikonin selectively inhibits the expression of TNF-alpha at the RNA splicing level. Treatment of lipopolysaccharide-stimulated human primary monocytes and THP-1 cells with shikonin resulted in normal transcriptional induction of TNF-alpha, but unspliced pre-mRNA accumulated at the expense of functional mRNA. This effect occurred with noncytotoxic doses of shikonin and was highly specific, because mRNA production of neither a housekeeping gene nor another inflammatory cytokine gene, interleukin-8 (IL-8), was affected. Moreover, cotreatment with lipopolysaccharide (LPS) and shikonin increased the endpoint protein production of IL-8, accompanied by suppressed activation of the double-stranded RNA-activated protein kinase (PKR) pathway. Because PKR inactivation has been shown to down-regulate the splicing process of TNF-alpha RNA and interfere with translation, our findings suggest that shikonin may achieve differential modulation of cytokine protein expression through inactivation of the PKR pathway and reveal that regulation of TNF-alpha pre-mRNA splicing may constitute a promising target for future anti-inflammatory application.

Shikonin isolated from the roots of the Chinese herb Lithospermum erythrorhizon has been associated with anti-inflammatory properties. /Investigators/ evaluated shikonin's chemotherapeutic potential and investigated its possible mechanism of action in a human cutaneous neoplasm in tissue culture. Shikonin preferentially inhibits the growth of human epidermoid carcinoma cells concentration- and time-dependently compared to SV-40 transfected keratinocytes, demonstrating its anti-proliferative effects against this cancer cell line. Additionally, shikonin decreased phosphorylated levels of EGFR, ERK1/2 and protein tyrosine kinases, while increasing phosphorylated JNK1/2 levels. Overall, shikonin treatment was associated with increased intracellular levels of phosphorylated apoptosis-related proteins, and decreased levels of proteins associated with proliferation in human epidermoid carcinoma cells.

... /A previous study showed/ that shikonin, a natural compound isolated from Lithospermun erythrorhizon Sieb. Et Zucc, inhibits adipogenesis and fat accumulation. This study was conducted to investigate the molecular mechanism of the anti-adipogenic effects of shikonin. Gene knockdown experiments using small interfering RNA (siRNA) transfection were conducted to elucidate the crucial role of beta-catenin in the anti-adipogenic effects of shikonin. Shikonin prevented the down-regulation of beta-catenin and increased the level of its transcriptional product, cyclin D1, during adipogenesis of 3T3-L1 cells, preadipocytes originally derived from mouse embryo. beta-catenin was a crucial mediator of the anti-adipogenic effects of shikonin, as determined by siRNA-mediated knockdown. Shikonin-induced reductions of the major transcription factors of adipogenesis including peroxisome proliferator-activated receptor gamma and CCAAT/enhancer binding protein alpha, and lipid metabolizing enzymes including fatty acid binding protein 4 and lipoprotein lipase, as well as intracellular fat accumulation, were all significantly recovered by siRNA-mediated knockdown of beta-catenin. Among the genes located in the WNT/beta-catenin pathway, the levels of WNT10B and DVL2 were significantly up-regulated, whereas the level of AXIN was down-regulated by shikonin treatment. This study ...shows that shikonin inhibits adipogenesis by the modulation of WNT/beta-catenin pathway in vitro, and also suggests that WNT/beta-catenin pathway can be used as a therapeutic target for obesity and related diseases using a natural compound like shikonin...

Anti-inflammatory agents that are non-steroidal in nature. In addition to anti-inflammatory actions, they have analgesic, antipyretic, and platelet-inhibitory actions. They act by blocking the synthesis of prostaglandins by inhibiting cyclooxygenase, which converts arachidonic acid to cyclic endoperoxides, precursors of prostaglandins. Inhibition of prostaglandin synthesis accounts for their analgesic, antipyretic, and platelet-inhibitory actions; other mechanisms may contribute to their anti-inflammatory effects.

Alkannin and shikonin are naturally occurring hydroxynaphthoquinones with a well-established spectrum of wound healing, antimicrobial, anti-inflammatory, and antioxidant activities. Recently, extensive scientific effort has been focused on their effectiveness on several tumors and mechanism(s) of antitumor activity. Liposomes have been proved as adequate drug carriers offering significant advantages over conventional formulations, such as controlled release and targeted drug delivery, leading to the appearance of several liposomal formulations in the market, some of them concerning anticancer drugs. The aim of the present study was to prepare shikonin-loaded liposomes for the first time in order to enhance shikonin therapeutic index. An optimized technique based on the thin film hydration method was developed and liposomes characterization was performed in terms of their physicochemical characteristics, drug entrapment efficiency, and release profile. Results indicated the successful incorporation of shikonin into liposomes, using both 1,2-dipalmitoylphosphatidylcholine and egg phosphatidylcholine lipids. Liposomes presented good physicochemical characteristics, high entrapment efficiency and satisfactory in vitro release profile. In vitro cytotoxicity of liposomes was additionally tested against three human cancer cell lines (breast, glioma, and non-small cell lung cancer) showing a moderate growth inhibitory activity. Practical applications: Shikonin is a naturally occurring hydroxynaphthoquinone and extensive scientific research (in vitro, in vivo, and clinical trials) has been conducted during the last years, focusing on its effectiveness on several tumors and mechanism(s) of antitumor action. The purpose of this work was to prepare and characterize shikonin-loaded liposomes as a new drug delivery system for shikonin. Liposomal formulations provide significant advantages over conventional dosage forms, such as controlled release and targeted drug delivery for an

... Mordant dye that produces violet to gray colors on fabrics. In Japan, shikonin was used to dye fabrics a color known as Tokyo Violet.

Tissue cultures are used in Japan to manufacture shikonin mainly for cosmetic use.

Shikonin has been used as a red dye for centuries and is reported to possess medicinal properties such as antibacterial, anti-inflammatory and antitumor activities. Has potential uses as an antibacterial and UV protective agent on silk fabrics.

Biological activities of shikonin include Amebicide; Antibacterial; Antiburn; Antidermatotic; Antiinflammatory; Antisarcomic; Antitumor; Cicatrizant; OMM /Oriental Materia Medica/; Pesticide

For more Uses (Complete) data for Shikonin (6 total), please visit the HSDB record page.

Shikonin is produced by a two-stage fermentation process.

... Occurs as an acetyl derivative in the Japanese shikone, Lithospermum erythrorhizon, another member of the Boraginaceae family. It is the (R)-optical isomer of alkannin. ...

The first product obtained from mass plant cell cultures was shikonin, a red pigment composed of eight naphthoquinone molecules.