Arthritis Rheum. 1975 Sep-Oct;18(5):493-6.
Mechanism of action of colchicine. III. Antiinflammatory effects of colchicine compared with phenylbutazone and indomethacin.

Chang YH.

Colchicine suppresses the development of carrageenan-induced edema in the rat with a minimum effective oral dose of 6.0 mg/kg. The slope of the dose-response regression line for colchicine differs significantly from that of indomethacin and phenylbutazone. Based on the dosages required to achieve a 50% suppression of this inflammation, colchicine is 0.6 and 1.5 times as potent as indomethacin and phenylbutazone, respectively. In the reversed passive Arthus reaction in the rat, the suppressive activity of colchicine is at least 50 times that of indomethacin and 100 times that of phenylbutazone. The possible significance of these results with regard to the unique effectiveness of colchicine in the treatment of gout is discussed.


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J Supramol Struct. 1976;5(3):335-42.
Suppression of stimulating cell activity by microtubule-disrupting alkaloids.

Ranney DF.

Microtubule-disrupting alkaloids and protein fixatives were used to investigate the nature of an active process that must occur within stimulator cells in order for them to initiate a unidirectional mixed lymphocyte response (MLR). Brief treatment of the stimulator cells (SC) with glutaraldehyde (0.15%), formalin (0.6%), or lanthanum chloride (10-3 M) abolished their capacity to activate responder cells (RC). Pretreatment of SC with microtubule-disrupting alkaloids, colchicine (c) (10-4 to 10-6 M) or colchicine + vincristine (c+v) (10-4 to 10-6 M) also abrogated their stimulating capacity. This capacity was not restored by the addition of supernates from untreated cultures, thereby excluding the possibility that the alkaloids acted by decreasing the release of soluble stimulatory factors from SC. The introduction of alkaloid-inactivated, mitomycin-treated RC as drug carriers did not affect the mitogenic response of untreated RC to concanavalin A. This excluded a significant leakage of alkaloids from the treated SC and uptake by RC during culture. Lumicolchicine produced no decrease in the stimulating capacity of SC. This suggested that the suppression induced by low concentrations of colchicine resulted from its specific disruption of microtubules. None of the above treatments quantitatively reduced the antigenicity of SC, as evaluated by humoral and cell-mediated lysis of the treated cells. Also, these treatments produced no significant changes in the specific binding of concanavalin A by SC. These results indicate there is a functional interaction of microtubular structures with cell surface antigens that appears to regulate either the capacity of SC to associate with RC, or the ability of SC to form and stabilize stimulatory antigenic configurations on the cell surface.


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Int J Impot Res. 2000 Sep;12 Suppl 3:S25-31.
Inhibition of Peyronie's plaque fibroblast proliferation by biologic agents.

Anderson MS, Shankey TV, Lubrano T, Mulhall JP.

Urology Research Laboratory, Hines VA, Hines, IL 60153, USA.

Peyronie's disease is a fibromatosis of the tunica albuginea which affects up to 2% of men. Plaque development is believed to result, at least in part, from fibroblast proliferation and excess collagen deposition. Numerous oral and intralesional therapies have been used, including verapamil, colchicine and steroids. The purpose of this study was to investigate the in vitro effects of prostaglandin-E1 (PGE1), verapamil and colchicine on the proliferation rates of fibroblasts derived from Peyronie's disease tissue. Using tissue culture, multiple cell lines comprising fibroblasts from Peyronie's plaque, normal tunica and foreskin were established. Cells of low passage were removed from the parent culture and incubated with varying concentrations of PGE1 (0.1-10 mg/ml), verapamil (10-1000 mg/ml), and colchine (2.5 mg/ml). Proliferation was assessed at 48, 72 and 96 hours using the Vybrant MTT cell proliferation and then compared to control cells. Six plaque lines and 5 normal tunical cell lines were established. These cell lines exhibited excellent linear growth in culture media alone. Co-culture wih PGE1 resulted in no significant inhibition at 0.1 and 1 mg/ml, but a mean inhibition of 60.6+/-11.5% at a concenrtation of 10 mg/ml was noted. Similar inhibition was noted with verapamil at 100 and 1000 mg/ml with a mean inhibition of 65.2+/-10.6%. Colchicine resulted in a mean inhibition of 28% at a concentration of 2.5 mg/ml. Maximum inhibition occurred at 96 hours in all cases. There was no statisitically significant difference in proliferation rates between plaque and normal tunical cell lines. We have developed an in vitro model to assess the effects of biologically active agents on the growth of fibroblasts derived from Peyronie's disease tissue. Our data suggests that PGE1, verapamil, and colchicine inhibit in vitro proliferation of fibroblasts at specific concentrations. Refinement and application of this knowledge may allow the development of useful pharmacologic strategies for men with PD.


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J Biol Chem. 2000 Dec 22;275(51):40443-52.
Mapping the binding site of colchicinoids on beta -tubulin. 2-Chloroacetyl-2-demethylthiocolchicine covalently reacts predominantly with cysteine 239 and secondarily with cysteine 354.

Bai R, Covell DG, Pei XF, Ewell JB, Nguyen NY, Brossi A, Hamel E.

Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, NCI-Frederick Cancer Research and Development Center, Frederick, Maryland 21702, USA.

2-Chloroacetyl-2-demethylthiocolchicine (2CTC) and 3-chloroacetyl-3-demethylthiocolchicine (3CTC) resemble colchicine in binding to tubulin and react covalently with beta-tubulin, forming adducts with cysteine residues 239 and 354. The adducts at Cys-239 are less stable than those at Cys-354 during formic acid digestion. Extrapolating to zero time, the Cys-239 to Cys-354 adduct ratio is 77:23 for 2CTC and 27:73 for 3CTC. Using energy minimization modeling to dock colchicinoids into the electron crystallographic model of beta-tubulin in protofilaments (Nogales, E. , Wolf, S. G., and Downing, K. H. (1998) Nature 391, 199-203), we found two potential binding sites. At one, entirely encompassed within beta-tubulin, the C2- and C3-oxygen atoms of 2CTC and 3CTC overlapped poorly with those of colchicine and thiocolchicine, but distances from the reactive carbon atoms of the analogs to the sulfur atoms of the cysteine residues were qualitatively consistent with reactivity. The other potential binding site was located at the alpha/beta interface. Here, the oxygen atoms of the analogs overlapped well with those of colchicine, but relative distances of the reactive carbons to the cysteine sulfur atoms did not correlate with the observed reactivity. A significant conformational change must occur in the colchicine binding site of tubulin in the transition from the unpolymerized to the polymerized state.


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