naphthoquinones and Pain

Impatiens balsamina is an annual herb of the Balsaminaceae family, which is cultivated extensively in Asia as an ornamental plant. Notably, as a folk medicine, I. balsamina has been long prescribed for the treatment of rheumatism, isthmus, generalized pain, fractures, inflammation of the nails, scurvy, carbuncles, dysentery, bruises, foot diseases, etc. AIM OF THE STUDY: The paper overviews comprehensive information on ethnobotanical uses, phytochemistry, pharmacological activity, and toxicity of I. balsamina, aiming at laying a sturdy foundation for further development of I. balsamina.. Research information was acquired through electronic databases such as Web of Science, PubMed, SciFinder, ScienceDirect, Google Scholar, and CNKI with the keyword "Impatiens balsamina ".. Briefly, more than 307 natural compounds have been separated and identified from various medicinal parts of I. balsamina, which are classified into diverse groups, like flavonoids, naphthoquinones, coumarins, terpenoids, sterols, phenols, fatty acids and their ester, naphthalene derivatives, nitrogen-containing compounds, polysaccharides, and other compounds. In particular, 2-methoxy-1,4-naphthoquinone, one of the naphthoquinones, is the predominant and most representative component. Moreover, I. balsamina furnishes numerous and complicated pharmacological activities, including antimicrobial, antiallergic, antipruritic, antitumor, antioxidant, anti-inflammatory, immunomodulatory, anti-hepatic fibrosis, insecticidal, and anthelmintic as well as enzyme-inhibiting activities, etc. Toxicological studies have shown that the hexane extract of the stems and leaves was less toxic, and the hydroalcoholic extract of stems was more toxic.. The paper contributes to updating the ethnobotanical uses, phytochemistry, pharmacological activity, and toxicity of I. balsamina, which offer abundant information for future investigations and applications of I. balsamina.

Topics: Ethnobotany; Ethnopharmacology; Impatiens; Medicine, Traditional; Naphthoquinones; Pain; Phytochemicals; Phytotherapy; Plant Extracts

Shikonin is an ointment produced from Lithospermun erythrorhizon which has been used in traditional medicine both in Europe and Asia for wound healing and is associated with anti-inflammatory properties. The goal of this work is to assess the analgesic properties of Shikonin in the CFA-induced inflammation model of pain. Rats were subjected to inflammation of the hind paw by CFA injection with a preventive injection of Shikonin and compared to either a control group or to a CFA-inflamed group with the vehicle drug solution. Inflammation of the hind paw by CFA was assessed by measurement of the dorsal to plantar diameter. Mechanical thresholds were established by means of the Von Frey filaments which are calibrated filaments that exert a defined force. Finally, the spinal cord of the studied animals was extracted to analyse the microglia population through immunohistochemistry using the specific marker Iba-1. Our results show that Shikonin reduces the paw oedema caused by CFA inflammation. Subsequently, there is a concomitant restoration of the mechanical thresholds reduced by CFA hind paw injection. Additionally, spinal microglia is activated after CFA-induced inflammation. Our results show that microglia is inhibited by Shikonin and has concomitant restoration of the mechanical thresholds. Our findings demonstrate for the first time that Shikonin inhibits microglia morphological changes and thereby ameliorates pain-like behaviour elicited by mechanical stimulation.

Topics: Animals; Disease Models, Animal; Hyperalgesia; Inflammation; Microglia; Naphthoquinones; Pain; Rats; Spinal Cord

Topics: Coloring Agents; Diagnosis, Differential; Exanthema; Humans; Hypersensitivity, Delayed; Male; Naphthoquinones; Pain

This study was designed to evaluate the antihyperalgesic effect of crude extract of Diospyros lotus followed by the isolation and characterisation of 7-methyljuglone in acetic acid and formalin tests. The pretreatment of crude extract evoked dose-dependent inhibition of noxious stimulation with maximum effect of 56.78% in acetic acid-induced writhing test, which were 51.89% and 60.69% in first and second phases, respectively, at 100 mg/kg i.p. The structure of 7-methyljuglone was confirmed by spectroscopic analysis. 7-Methyljuglone evoked profound increase in pain threshhold dose dependently; when it was studied in acetic acid-induced writhing test with 63.73% pain attenuation while 51.22% and 65.44% pain amelioration in first and second phases, respectively, at 100 mg/kg i.p. In conclusion, crude extract and 7-methyljuglone of D. lotus roots possessed both peripheral and central antinociceptive potential and thus could be a useful new therapeutic agent.

Topics: Analgesics; Animals; Diospyros; Female; Male; Mice, Inbred BALB C; Molecular Structure; Naphthoquinones; Pain; Plant Extracts; Plant Roots

Cipura paludosa (Iridaceae) is a plant that is distributed in the north region of Brazil. Its bulbs are used in folk medicine to treat inflammation and pain. Four naphthalene derivatives have been isolated from the bulbs of this plant. Three of them have been identified as the known naphthalene derivatives, eleutherine, iso-eleutherine, and hongkonin. The structure of the fourth and new component was determined as 11-hydroxyeleutherine by extensive NMR study. In addition, the IN VIVO effect of the two major compounds, eleutherine and iso-eleutherine, was evaluated in carrageenan-induced hypernociception and inflammation in mice. Eleutherine and iso-eleutherine (1.04-34.92 µmol/kg), dosed intraperitoneally (i.p.) or orally (p.o.), decreased the carrageenan-induced paw oedema (i.p. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively; p.o. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively). Iso-eleutherine, but not eleutherine, significantly reduced (inhibitions of 39 ± 4 %) the plasma extravasation induced by intradermal (i.d.) injection of carrageenan. Likewise, eleutherine and iso-eleutherine (1.04-34.92 µmol/kg, i.p. or p.o.) were also effective in preventing the carrageenan-induced hypernociceptive response (i.p. - inhibition of 59 ± 4 % and 63 ± 1 %, respectively; p.o. - inhibitions of 36 ± 7 % and 58 ± 14 %, respectively). It was also suggested that the anti-inflammatory and anti-hypernociceptive effects of eleutherine or iso-eleutherine partly depend on the interference with the synthesis or activity of mast cell products, kinins, cytokine, chemokines, prostanoids, or sympathetic amines. Our findings show that two major compounds of C. paludosa contain pharmacologically active constituents that possess antinociceptive and anti-inflammatory activity, justifying, at least in part, its popular therapeutic use for treating conditions associated with pain.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents, Non-Steroidal; Brazil; Carrageenan; Drug Evaluation, Preclinical; Edema; Female; Inflammation; Injections, Intraperitoneal; Iridaceae; Magnetic Resonance Spectroscopy; Male; Mice; Molecular Structure; Naphthoquinones; Pain; Plant Roots; Plants, Medicinal

Crude ethanolic extract of Lawsonia inermis L. (0.25-2.0 g/kg) produced significant and dose-dependent anti-inflammatory, analgesic, and antipyretic effects in rats. The extract also produced significant increases in pentobarbitone-induced sleeping time. Using a liquid-liquid extraction procedure, the extract was fractionated into chloroform, butanol, and water fractions, and these were tested for the above activities. The butanol and chloroform fractions showed more potent anti-inflammatory, analgesic, and antipyretic effects than the crude extracts, while the aqueous extract showed significantly less effect. As compared with the other extracts, the butanolic extract (500 mg/kg) was the most effective in the analgesic test. From the chloroform extract, a pure compound was isolated and identified, using chromatographic and spectroscopic techniques, as 2-hydroxy-1,4-naphthaquinone (lawsone). The isolated compound was found to possess significant anti-inflammatory, analgesic, and antipyretic activity. It potentiated significantly the pentobarbitone-induced sleeping time. The anti-inflammatory effect of lawsone (500 mg/kg) was not significantly different from that of the reference drug phenylbutazone (100 mg/kg).

Topics: 1-Butanol; Administration, Oral; Analgesics, Non-Narcotic; Analysis of Variance; Animals; Anti-Inflammatory Agents; Antifungal Agents; Body Temperature; Butanols; Chemical Fractionation; Chloroform; Chromatography, Thin Layer; Dose-Response Relationship, Drug; Edema; Ethanol; Male; Naphthoquinones; Pain; Plant Extracts; Plants, Medicinal; Rats; Rats, Wistar; Sleep

Topics: Benzoquinones; Capillaries; Carbohydrates; Humans; Inflammation; Naphthoquinones; Oxidoreductases; Pain; Patient Discharge; Quinones