shikonin and Granuloma

The naphthoquinone pigment, shikonin, isolated from Lithospermum erythrorhizon Sieb. et Zucc.(Boraginaceae) and its derivatives are the active components isolated from the Chinese herbal therapeutic, Zicao. Historically, Zicao root extracts have been used to treat macular eruption, measles, sore-throat, carbuncles and burns. Multiple pharmacological actions have been attributed to shikonin, e.g. antiinflammatory, antigonadotropic and anti-HIV-1 activity. In this review, several therapeutic applications of shikonin will be summarized including its pleiotropic, antiinflammatory and antitumour effects. Widely diverse and sometimes conflicting activities have been attributed to shikonin, e.g. wound healing, enhanced granuloma formation, suppression of local acute inflammatory reactions, inhibition of angiogenesis, inhibition of select chemokine ligands, inhibition of DNA topoisomerase activity, inhibition of platelet activation and antimicrobial activity. Comparison of the various reported mechanisms of action for shikonin lead us to hypothesize that shikonin is an effective inhibitor of protein-protein interaction with multiple targets in both the intracellular and extracellular compartments. This general inhibitory effect can account for the broad spectrum of shikonin biological and pharmacological activities.

Topics: Animals; Anti-Infective Agents; Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents, Phytogenic; Granuloma; Humans; Inflammation; Lithospermum; Mast Cells; Naphthoquinones; Neoplasms; Neutrophils; Phytotherapy; Plant Extracts; Platelet Aggregation Inhibitors; Prostaglandin-Endoperoxide Synthases; Respiratory Burst; Signal Transduction; Wound Healing

"The extract of shikon" (SK) and shikonin play important roles in the development of granulomatous tissue formation. To reveal the augmenting effect of SK or shikonin on vascular endothelial growth factor (VEGF) production and neovascularization, we investigated murine granulomatous tissue induced by SK and shikonin, comparing them to pouches in which trehalose 6,6'-dimycolate (TDM) was injected. The development of granulomatous tissue formation was evaluated by the wet weight of pouch walls. At day 5 and 7 after SK and shikonin injection, prominent granulomatous tissue formation was detected. Histological observations on the development of granulomatous tissue showed that the pouch was formed in the submuscular connective tissue and necrotic tissue directly facing the cavity and granulomatous tissue developed in the connective tissue. At day 1, VEGF-positive neutrophils accumulated in the pouch wall. Granulomatous tissue formation and neovascularization by injection of SK or shikonin was not more prominent than TDM. However, the present results indicate that SK and shikonin induce neovascularization in granulomatous tissue.

Topics: Animals; CD3 Complex; Endothelial Growth Factors; Flow Cytometry; Granuloma; Lymphokines; Macrophage-1 Antigen; Male; Mice; Mice, Inbred ICR; Naphthoquinones; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

This study was carried out to compare the accelerative effect in ether extracts of "Koushikon" and "Nanshikon" on proliferation of granuloma tissue in rats, and to elucidate this effect on optical isomer of naphthoquinone derivatives in those extracts. The content of total naphthoquinone derivatives in the ether extracts of Koushikon and Nanshikon were found to be 56.1% and 25.4%. Among naphthoquinone derivatives, Koushikon contained mostly acetyl derivative and Nanshikon mostly teracryl derivative. The percentage of R-type (shikonin-type) in total naphthoquinone derivatives of the extracts was 85.5% and 3.8%. Each ether extract showed a dose-dependent acceleration on the cotton pellet-induced granuloma formation. Comparison with corresponding doses containing the same quantity of naphthoquinone derivatives showed the accelerative potency of ether extracts of Koushikon and Nanshikon to be about the same. The result suggests that the accelerative effect on proliferation of granuloma tissue depends primarily on the total content of naphthoquinone derivatives, and not on the ratio of the optically active isomers.

Topics: Animals; Cell Division; Drugs, Chinese Herbal; Granuloma; Male; Naphthoquinones; Rats; Rats, Wistar; Stereoisomerism

Of twelve reduced and acetylated derivatives of shikonin, a chemical constituent of Shikon, the accelerating activity on granuloma formation and the inhibitory activity on delayed-type allergy were investigated in order to find a compound having more characteristic effect than shikonin on wound healing in experimental animals. As a result, it was found that a reduced and pentaacetylated derivative of shikonin, MDS-004, has more excellent pharmacological activity. MDS-004 (0.1-1 mg/pellet) accelerated dose-dependently felt-pellet-induced granuloma formation when given topically together with felt-pellets in rats. It also produced strong inhibition against delayed-type allergies (ear edema) caused by oxazolone and dinitrofluorobenzene by topical application of up to 1 mg/ear to the ear skin of mice; its potency was far superior to that of shikonin. Orally administered MDS-004, unlike shikonin, inhibited carrageenan-induced hind paw edema, and exhibited tendency to heal acetic acid-induced gastric ulcer in rats. However, MDS-004, as well as commercial wound healing drugs tested and shikonin, did not show any healing action in the incised and open wound models in rats, if applied topically to the wound as 5 and 10% powders. On the other hand, MDS-004 did not produce irritative action on the ear skin at a topical dose of 1 mg/ear different from shikonin, and any behavioral changes after oral administration of 100 mg/kg in mice. These results suggest that a white powder MDS-004, different from deep purple shikonin, has accelerating action on granuloma formation without irritative action and stronger inhibitory action on delayed-type allergy by topical application than shikonin.

Topics: Animals; Granulation Tissue; Granuloma; Hypersensitivity, Delayed; Male; Mice; Mice, Inbred Strains; Naphthoquinones; Rats; Rats, Inbred Strains; Wound Healing