Pharmacology of Chitraka (Plumbago zeylanica) Part 2
Pharmacology of Chitraka (Plumbago zeylanica) Part 2
Dr. Hemant Vinze M. S.
Actions on CNS
Aqueous, ethanol, chloroform, petroleum ether and acetone extracts of leaves of Chitraka (Plumbago zeylanica) were tested for analgesic activity in rats. The study revealed that the acetone and petroleum ether extracts significantly decreased pain only in the later phases of formalin test, suggesting that the drug could be acting peripherally. The analgesic action of Chitraka (Plumbago zeylanica) was attributed to plumbagin. 
The plant callus is a growing mass of unorganized plant parenchyma cells. The callus extract and the root extract of Chitraka (Plumbago zeylanica) were evaluated for central and peripheral analgesic activity. The study revealed that at 200 mg/kg, the root extract and at 400 mg/kg the callus extract displayed significant analgesic activity in experimental animal (mice) models. 
In Ayurveda herbs are grouped according to their prominent pharmacological actions. The groups are called ‘Ganas’. Chitraka (Plumbago zeylanica) is grouped in ‘Aamalakyaadi Gana’. Manoj J et al, evaluated actions of ‘Aamalakyaadi Gana’ on CNS in Wistar albino rats. The study showed that the ‘Gana’ showed antipyretic, analgesic activity. As Chitraka (Plumbago zeylanica) belongs to ‘Aamalakyaadi Gana’, it was concluded that by inhibiting synthesis of prostaglandin locally Chitraka (Plumbago zeylanica) shows antipyretic activity. Further, Chitraka (Plumbago zeylanica) also has analgesic effect through central and peripheral mechanism. These effects are dose dependent. 
The chloroform extract of root of Chitraka (Plumbago zeylanica) at 200mg/kg body weight has shown promising memory enhancing effect in mice brain. The antioxidant effect of Chitraka (Plumbago zeylanica) was said to be effective in reversing amnesia induced by scopolamine at 0.4mg/kg body weight. The herb also enhanced the learning ability of mice. 
Some researchers have reported anti-inflammatory and analgesic activity of hydro-alcoholic extract of leaf of Chitraka (Plumbago zeylanica). 
The dried extract of root of Chitraka (Plumbago zeylanica) may ameliorate Parkinsonism without developing side effects. 
In an experimental study, single oral dose of 100, 200, 300 mg/kg body weight of 50 % ethanol extract of root of Chitraka (Plumbago zeylanica) significantly increased the spontaneous motility in animals. 
Actions on CVS
A study showed that plumbagin administered to hyperlipidaemic rabbits, lowered total cholesterol by 53 to 86 percent and LDL-cholesterol by 61 to 91 percent. It lowered cholesterol/phospholipid ratio by 45.8 percent. Plumbagin also elevated significantly the lowered level ofHDL-cholesterol. Further, plumbagin prevented the accumulation of cholesterol and triglycerides in liver and aorta. Plumbagin regressed the atheromatous plaque in thoracic and abdominal aorta. Wheh treated with plumbagin, hyperlipidaemic subjects excreted more cholesterol and phospholipids in faeces. , 
Actions on RS
A study showed that plumbagin had the ability to suppress the non-small cell carcinoma of the lung 
Actions on GI System
Feeding of root of Chitraka (Plumbago zeylanica) has been shown to proliferate coliform bacteria in mice. This activity is similar to that of ‘Mexaform’. Chitraka (Plumbago zeylanica) normalizes gastrointestinal flora. Scientists attribute digestive stimulant and appetizer activity of Chitraka (Plumbago zeylanica) to this normalization of gastrointestinal flora. 
Recently Helicobacter pylori is shown to be associated with peptic ulceration and gastric cancer. A study showed that Chitraka (Plumbago zeylanica) had the highest inhibitory effect against Helicobacter pylori. Thus Chitraka (Plumbago zeylanica) prevents the development of peptic ulcer and gastric carcinoma. 
To investigate antiulcer activity of Chitraka (Plumbago zeylanica), peptic ulcer was induced in albino rats by administering aspirin and indomethacin. Ulcer score and ulcer index were recorded. The aqueous extract of root of Chitraka (Plumbago zeylanica) was then administered at doses of 25, 50 and 100mg/kg bodyweight. Depending upon the dose, the extract showed ulcer healing effect in aspirin induced ulcers while in the indomethacin-induced ulcers 50 and 100 mg/kg body weight showed significant ulcer healing activity. 
Increasing evidence indicates that CXC chemokine receptor -4 is critical in the process of metastasis of gastric cancer. By downregulating the expression of chemokine receptor CXCR4, plumbagin inhibits invasion and migration of gastric cancer cells. 
To investigate the efficacy of Chitraka (Plumbago zeylanica) against intestinal cancers, by injecting subcutaneously azoxymethane at 15 mg/ kg bodyweight, once weekly for 3 weeks, intestinal cancers were induced in male F344 rats. The animals were then treated with plumbagin isolated from Chitraka (Plumbago zeylanica). The animals showed regression of cancers.
In another group the animals given plumbagin along with the carcinogen had a lower incidence of tumors in the entire intestine.
These data suggest that plumbagin from Chitraka (Plumbago zeylanica) could be a promising chemopreventive agent for human intestinal neoplasia. 
Actions on Liver
In a study plumbagin in ethanolic extract of Chitraka (Plumbagin zeylanica) protects liver from paracetamol-induced toxicity. Furthermore, in rats, at 300mg/kg bodyweight plumbagin normalized the elevated levels of liver enzymes in paracetamol-induced hepato-toxicity. Plumbagin also protected the liver against paracetamol-induced hepatocellular injury as was evident on histopathological study. 
In another study on Wistar rats, the methanolic extract of aerial parts of Chitraka (Plumbagin zeylanica) protected the liver from carbon tetrachloride (CCl4)-induced hepatotoxicity as was evident by normalization of elevated levels of total serum bilirubin, SGOT and SGPT. Histological studies also displayed the normalization of liver structure. The methanolic extract of aerial parts of Chitraka (Plumbagin zeylanica) was superior to 100 mg/kg bodyweight per animal of silymarine in hepatoprotection. 
A study showed that plumbagin found in Chitraka (Plumbagin zeylanica) inhibited cell proliferation of hepatocellular carcinoma and accelerated apoptosis of Hep G2 cells. Plumbagin also inhibited Hep G2 cell invasion. The effect was dependent on the dose used. 
By restraining the mRNA and protein expression of α-smooth muscle actin (α – SMA) plumbagin found in Chitraka (Plumbagin zeylanica) could inhibit the activation and proliferation of human hepatic stellate-LX2 (HSC-LX2) cells. Plumbagin can also have antihepatic fibrosis effect. 
Experimental study on mice suggested that antihepatic cancer activity of plumbagin was due to the elevated levels of cytokine IL-2 and TNF- α. Plumbagin also showed anti-tumor activity in vivo. 
In Kunming mice plumbagin prolonged the survival time of H22 ascites hepatoma bearing animals. Plumbagin also stabilized or increased the body weight of these animals. 
Actions on Pancreas
In an experimental study in the United States, administration of plumbagin isolated from root of Chitraka (Plumbagin zeylanica) was found to inhibit, in vitro and in vivo, the growth of pancreatic cancer cells. Plumbagin was found to induce apoptosis in pancreatic cancer cells. Furthermore, intra-peritoneal administration of plumbagin in rats, at doses of 2 mg/kg bodyweight 5 days a week resulted in significant inhibition of tumor both in weight and volume. These results suggest that plumbagin may be a useful therapeutic agent against human pancreatic cancer. 
In experimentalstudy on laboratory animals plumbagin isolated from Chitraka (Plumbagin zeylanica) inhibited the groth of pancreatic cancer (Panc-1 and Bxpc-3) cells in a dose dependent manner. The degree of apoptosis was assessed by measuring the proportions of sub-G (1), annexin V+/propidium iodide, and terminal-deoxynucleotidyl-transferase-mediated-nick-end labeling (TUNEL) + cells. A significant increase in apoptotic calls was observed. Exposure to plumbagin caused upregulation of Bax, rapid decline in mitochondrial transmembrane potential, apoptosis-induced factor over expression in cytosol and cleavage of procaspage-9 and ADP-ribose polymerase. Pretreatment with caspase inhibitors did not block plumbagin-induced apoptosis. 
Actions on metabolism
A study conducted on obese patients by Kotecha M and Rao K S (2007) in Gujarat, India showed that Chitraka (Plumbagin zeylanica) powder at the dose of 500 mg/kg bodyweight four times a day for 45 days with restricted, low calorie diet showed that Chitraka (Plumbagin zeylanica) was useful for the treatment of obesity. 
Sharma et al demonstrated hypocholesterolemic activity of Chitraka (Plumbagin zeylanica). The study was carried out in hyper-lipidemic rabbits with active component plumbagin. The study showed that plumbagin lowered total serum cholesterol by 53 to 86% and LDL-cholesterol by 61 to 91%. Furthermore plumbagin prevented the accumulation of cholesterol and triglycerides in the liver and aorta.
Another study on hyperlipidemic rabbits showed that administration of ethanolic extract of roots of Chitraka (Plumbagin zeylanica) at doses of 500 mg/kg body weight with normal diet for two months significantly lowered total cholesterol, LDL cholesterol and triglyceride. The reduction was almost double when given in combination with Vitamin E. 
A study on hyperlipidemic rabbits showed that, treatment with plumbagin not only prevented the accumulation of cholesterol and triglycyrides in the liver and aorta but also regressed atheromatous plaque of thoracic and abdominal aorta. Treatment with plumbagin helped excrete more cholesterol and phospholipids in faeces in hyperlipidemic rabbits. , 
Actions on Diabetes
To evaluate effects of plumbagin isolated from Chitraka (Plumbagin zeylanica) in streptozotocin-induced diabetic rats, plumbagin was administered orally at doses of 15 and 30 mg/kg bodyweight to streptozotocin-induced diabetic rats for 28 days. The results showed that plumbagin significantly lowered raised blood sugar and significantly altered all other parameters to near normal levels.
[In the paper, method of isolation of plumbagin (aqueous, alcoholic or hydro-alcoholic) is not mentioned]
Some researchers observed hyperglycaemia in rats treated with ethanolic extract of root of Chitraka (Plumbagin zeylanica), while most researchers have reported antidiabetic (hypoglycaemic) activity. To evaluate these contradictory results, Olangunju et al studied the biochemical basis of the effects of ethanolic extract of Chitraka (Plumbagin zeylanica) on key enzymes of glycolysis and other biochemical parameters in rats. The results showed that hexokinase, phosphofructokinase, pyruvate kinase and lactate dehydrogenase activities in thigh muscles were significantly reduced. The protein synthesis in the muscles was not affected. The serum pyruvate and lactate were significantly lowered. The reduction in the activities of the key enzymes of glycolysis and its end products suggest a reduction in flux across the glycolytic pathway. This may be a result of impaired delivery to, and utilizitation of, glucose by peripheral tissue.
(In the study by Olangunju et al it is not mention whether the animals treated with ethanolic extract of root of Chitraka (Plumbagin zeylanica) were diabetic, euglycaemic or hypoglycaemic)
Glucose transporter type-4 (GLUT-4) is a protein encoded in humans by the SLC 2A4 gene. It is insulin-regulated glucose transporter. It is found primarily in adipose tissues and skeletal and cardiac muscle (striated muscle). At the cell surface glucose transporter type-4 (GLUT-4) facilitated diffusion of circulating glucose down its concentration gradient into muscle and fat cells. Once within cells, glucose is rapidly phosphporylated by glucokinase in the liver and hexokinase in other tissues to form glucose-6-phosphate, which then enters glycolysis or is polymerized into glycogen. Glucose-6-phosphate cannot diffuse back out of cells, which also serves to maintain the concentration gradient for glucose to passively enter cells.
These studies on hypoglycaemia and hyperglycaemia caused by plumbagin/ Chitraka (Plumbagin zeylanica) led to a concept of “glucose homeostasis” in cells, adipose tissue and muscle.
[Plumbagin/ Chitraka (Plumbagin zeylanica) enhanced GLUT4 transportation and contribution to glucose homeostasis.]
This makes Chitraka (Plumbagin zeylanica) an unique herb in the treatment of diabetes. , , 
NADPH oxidase 4 (Nox 4) is reported to be the major source of reactive oxygen species (ROS) in the kidneys during the early stages of diabetic nephropathy. A study demonstrated that plumbagin at a dose of 2mg/kg body weight prevents the development of diabetic nephropathy through Nox 4 signaling pathways. 
Actions on Male Reproductive System
For years Chitraka (Plumbagin zeylanica) has been used for regulation of male fertility. 
Plumbagin induces apoptosis in prostate cancer cells. This anticancer activity was attributed to antioxidant property of Chitraka (Plumbagin zeylanica). 
Another study on mice showed that administration of plumbagin from Chitraka (Plumbagin zeylanica) at 2mg/kg body weight, five days in a week for eight weeks inhibited the growth of prostate cancer. There was a significant inhibition of metastases also. These results were confirmed by histopathology of these organs. 
Treatment with plumbagin from Chitraka (Plumbagin zeylanica) at the dose of 2mg/kg body weight also arrested or delayed the development and growth of metastases from hormone refractory prostate cancer by three weeks. Discontinuation of plumbagin for as long four weeks did not result in progression of tumor growth or metastases. 
Actions on Female Reproductive System
In female Wistar rats, plumbagin-free alcohol extract of root of Chitraka (Plumbagin zeylanica) at the doses of 300 and 500 mg/kg body weight exhibited significant anti-implantation and abortificient activity. These effects were dose-dependent. These effects were possibly through the changes in the implantation site, altered hormonal levels, prolonged estrous cycle and anti-estrogenic activity. The extract posseses reversible antifertility activity without adverse toxicity in female rats. 
Another study on female albino rats revealed that acetone and ethanol extracts of leaves of Chitraka (Plumbagin zeylanica) at doses of 200 and 4oo mg/kg body weight were effective in interrupting the estrous cycle of the animals. The animals exhibited a prolonged diestrous stage of estrous cycle corresponding to a temporary inhibition of ovulation. This is the mechanism of antifertility activity of Chitraka (Plumbagin zeylanica). The effect was dose dependent. The antiovulatory activity was reversible on discontinuation of the treatment. 
A study on female albino rats showed that treatment of pregnant rats during first seven days of pregnany with Chitraka (Plumbagin zeylanica) root powder destroyed uterine luminal proteins the of molecular weights 13,000, 19,000, 26, 000 and 75,000 Da (Dalton) resulted in loss of embryo in preimplantationary period. This suggested that these proteins influence the implantation of embryo and continuation of the pregnancy; their destruction results in abortion. 
Radiotherapy is the primary line of treatment for cervical cancer. However radiotherapy is limited by total dose that can be given without damaging normal tissue. In a study plumbagin from Chitraka (Plumbagin zeylanica) sensitized cervical cancer cells to radiation increasing the safety to normal tissue. This supplementation of plumbagin from Chitraka (Plumbagin zeylanica) showed a five fold increase in the activation of caspase 3 in C33A cells. Plumbagin also modulated the expression of apoptotic regulatory molecules Bcl-2, Bax and Survivin. This study showed that combination of plumbagin and radiation is a better way to inhibit the growth of cervical cancer than higher dose of radiation alone. 
Another study showed that plumbagin induced cell death in cervical cancer cell line ME-180. The cytotoxic effect of plumbagin-induced cell death was said to be through the generation of reactive oxygen species (ROS) and subsequent induction of apoptosis. Treatment of cancer cells with plumbagin caused loss of mitochondrial membrane potential and morphological changes observed in cell apoptosis such as nuclear condensation, DNA fragmentation and translocation of phosphatidyl serine. Moreover, plumbagin-induced apoptosis involved release of mitochondrial cytochrome c and AIF (apoptosis inducing factor), thus activating caspase-dependent and caspase-independent pathways. 
In Swiss albino mice, pretreatment with alcoholic extract of root of Chitraka (Plumbagin zeylanica) at doses of 250 and 500mg/kg body weight orally for five days protected the animals from cyclophosphamide-induced genetoxicity and oxidative stress. 
Plumbagin derived from Chitraka (Plumbagin zeylanica) inhibited NF- κB activation induced by tumor necrosis factor (TNF), other carcinogens and carcinogenic inflammatory stimuli such as H2O2, cigarette smoke condensate, okadaic acid, lipopolysaccharide, interleukin-1 β and phorbol 12-myristate 13-acetate. Plumbagin also suppressed activation of NF- κB in certain tumor cells. Cellular proliferation, carcinogenesis and radioresistence are regulated by the activation of transcription factor NF- κB. This suggests that plumbagin might affect NF- κB activation pathway. Plumbagin also suppressed the direct binding of nuclear p65 and recombinant p65 to DNA. Plumbagin down-regulated the expression of NF- κB-regulated anti-apoptotic, proliferative and angiogenic gene products. This may explain cell growth modulatory, anticarcinogenic and radiosensitizing effects of plumbagin. 
By using various solvents such as water, methanol, ethanol, water+alcohol, chloroform, dichloromethane etc. cytotoxic phytochemicals identified/isolated from Chitraka (Plumbagin zeylanica) are: β-sitosterol, β-sitosteryl-3- β-glucopyranoside, β-sitosteryl-3- β-glucopyranoside-6’-O-palmitate, lupenone, lupeol acetate, plumbagin and trilinolein. Of these cytotoxic compounds, β-sitosterol and plumbagin showed cytotoxicity against MCF7 and Bowes cancer cell lines. 
Another group of investigators identified and isolated important groups of cytotoxic drugs from roots of Chitraka (Plumbagin zeylanica): Plumbagic acid glucosides (3’-O- β-pyranosoyl plumbagic acid and 3’-O- β-pyranosoyl plumbagic acid methylester) and five naphthaquinones (plumbagin, chitranone, maritinone, elliptinone and isoshinanolone) and five coumarins (seselin, 5’-methoxyseselin, suberosin, xanthyletin and xanthoxyletin). Of these, plumbagin suppressed growth of Raji, Calu-1, HeLa and Wish tumor cell lines. 
In acute toxicity study, the methanolic extract of Chitraka (Plumbagin zeylanica) did not show toxicity up to the highest dose of 2000 mg/kg body weight. However doses 100, 200 and 400 mg/kg body weight are selected for pharmacolological use. 
Some researchers have reported adverse brain toxicity of methanol extract of root of Chitraka (Plumbagin zeylanica) at dose of 160mg /kg body weight, repeated during 15 days. Alteration in biochemical parameters was noted with significant changes in levels of LPO, GOT andGPT activities. There were significant changes in the histopathological studies in the brain. 
In Ethiopia Chitraka (Plumbagin zeylanica) used for skin diseases was seen to show systemic and dermatotoxicity. Methanol extract of root of Chitraka (Plumbagin zeylanica) having 80% concentration produced moderate skin irritation and ear swelling in rats.
Repeated dose administration was associated with increased weight of testes, higher values of blood urea nitrogen and potassium in both sexes of rats. These toxic effects were observed at hightest dose 1000mg/kg body weight. 
Toxicity of plumbagin was not found to be mediated by cell membrane but was mediated by oxidative stress. 
Chitraka (Plumbago zeylanica) should not be used in women of child bearing age and pregnant women.
Chitraka (Plumbago zeylanica) should not be used beyond recommended doses.
Chitraka (Plumbago zeylanica) should not be used in subjects having neurological disorders. 
Traditional and Ayurvedic uses
As anti-inflammatory and anti-edema (Shothaghna)
As analgesic (Wedanana-shamak)
As antipyretic (Jwaraghna), diaphoretic (Sweda-janana)
In impaired weak digestion as appetizer and digestive (Deepana, Paachana)
As anthelmintic (Krimighna)
In diarrhea, dysentery (As grahee in atisaar, in dysentery, in colitis)
Arsha (Piles, fissures in ano)
Udara/ Jalodara (Ascites, cirrhosis of the liver)
As antitussive (Kaasaghna, in bronchitis)
In bronchial asthma (Shwaasa)
In skin disorders, leucoderma, leprosy (Kushtaghna)
In anaemia (Pandu roga)
In obesity for weight loss (Lekhana)
As adaptogen (Rasaayana)
Boils, furuncles, abscesses (Gulma)
Wounds, ulcers (Wrana)
Shleepada (Filariasis, filarial edema) , , 
Inflammations: Chew two leaves of Chitraka (Plumbago zeylanica) twice a day. Alternatively apply paste of leaves to inflamed area.
Atisaar (Diarrhea): Mix half a tablespoonful of powder of root of Chitraka (Plumbago zeylanica) with one glass of warm water, take it twice a day.
Piles: Dust the powder of the root of Chitraka (Plumbago zeylanica) to affected area
Liver Tonic: Crush dried Chitraka (Plumbago zeylanica) plant to make powder, take two grams of powder with lukewarm water twice a day.
Scrofula (Tubercular lymphadenopathy): Crush leaves of Chitraka (Plumbago zeylanica), make paste, mix with castor oil, warm it and apply to the affected part
Scabies: Apply milky juice of Chitraka (Plumbago zeylanica) to the affected part
Skin diseases: Crush leaves of Chitraka (Plumbago zeylanica) , make paste and apply to affected parts twice a day
Leprosy: To powder of Chitraka (Plumbago zeylanica) add water, make paste and apply to skin lesions.
Extensive Skin disease: Sprinkle roor powder on affected areas. Alternatively mix the powder of the root of Chitraka (Plumbago zeylanica) in bathing water and take bath with this medicated water. 
Preparations and doses
Purification of Chitraka
Usually purification of Chitraka (Plumbago zeylanica) is not required and not done. Some authors recommend purification of Red Chitraka (Plumbago rosea)
Procedure ofpurification: Cut roots of Red Chitraka (Plumbago rosea) in small pieces, immerce them in 3-4% lime water, allow to steep for 3-4 hours, change lime water every 3 hours, repeat the process 3-4 times, takeout the roots, they are ready to use now.
Some authors have mentioned to steep roots for three days, changing lime water every day. 
Dose: The usual dose of root powder is 1-3 grams once to thrice a day.
Kushtha, Twachaa roga: Root powder 1-3 grams with cow’s urine three times a day
Atisaar: Root powder 1-2 grams three times a day
Arsha: Root powder 1-2 grams with butter milk three times a day
Medoroga, medaatya: Root powder with honey 1-2 grams
Shleepad, wounds, ulcers: The root paste is applied to affected parts
Twacharoga (Dermatitis): Prepare paste by mixing root powder with water and apply to affected parts
Sandhiwaata, Sandhishoth (Arthritis): Chitraka tailam (Medicated oil) prepared by boiling chitraka moola (roots) with sarpagandha in mustard oil, is to be applied to joints.
Scabies: Prepare paste of leaves or bark powder with haridraa (turmeric) and apply to the affected areas.
Rasaayana (Rejuvenator, Adaptogen): Root powder 1-2 grams to be consumes with cow ghee and tila tailam (sesame oil) for one year.
Choorna (Powder): 1-2 gram
Kwatha Decoction: 25-50 ml
Chitrakaadi watee (Chitraka tablets): 2 tablets twice a day with water , 
References from Ayurvedic Texts /Manuscripts
Grahanee (Chronic diarrhea, dysentery, Colitis): Chitrakaadi Gutika (Pills), Chitraka ghrita
[Charaka Samhitaa, chikitsaa sthaana, 15/96-97]
Arsha: Kalka of chitraka mixed with shunthee and gruel is applied to fissures, piles. Pealed bark is made into kalka, mixed with takram (buttermilk) to be taken orally
[Charaka Samhitaa, chikitsaa sthaana, 14/68; Charaka Samhitaa, chikitsa sthaana, 14/76; Sushrut Samhitaa, chikitsa sthana 6/13]
Pandu (anaemia): Chitraka moola + Bala moola 10 grams to be taken with warm water; or alternatively shigru beeja (seeds of drumstick) mixed with equal salt (such a patient should be on milk diet)
[Sushrut Samhita, Uttar tantra, 44/26]
Udara roga (Ascites): Chitrakadi ghrita
[Charaka Samhitaa, chikitsaa sthaana, 13/116]
Shotha (Inflammation, Edema): Local application of warm paste:
Chitraka+Devadaaru, Chitraka+ Powdered seeds of Drum stick with go-mootra (cow urine), Chitraka+ Sarshapa (Mustard)
[Vr. Ma. 42/5]
Chitrakaharitakee [Vr.Ma. 60/26-28]
Chitrakaadi ghrita [Charaka samhita Da. 4/43]
Chitraka rasaayana [Ashtaang Hridaya 3/39, 62-65]
Chitrakaadi choorna: [Charaka samhitaa, chikitsaa sthaana 12/58-59]
Chitraka Kashaaya: [Sushruta samhitaa, chikitsasthaana 11/9]
Shaddharana Yoga: [Sushruta samhitaa, chikitsasthaana 4/2] , 
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