Cord factor toxicity

Some of these compounds had a certain degree of cord-factor toxicity ... 

The purification and isolation of cord factor was greatly facilitated by its particular delayed toxicity for mice (upon repeated injections of microgram quantities). For detailed reviews on cord factor, see Refs. 25 and 26. 

Isolation of Cord Factor.—In Bloch s first paper, it had been shown that a petroleum-ether treatment of living bacteria extracts a crude lipid having the particular toxicity of cord factor. As the yield in these extractions was rather low, other lipid fractions extracted from whole bacilli were examined and it was found that cord factor is present in preparations of wax C and wax D —principally, however, in the former. 

A toxic lipid isolated by Spitznagel and Dubos by extraction of Mycobacteria with monochlorobenzene has been shown to contain cord factor as the only active compound. ... 

The chemistry of cord factor, a toxic lipid of virulent or attenuated Mycobacteria has already been described in detail (see p. 210). It has also been mentioned that at least part of this biological activity can be explained by the action of cord factor on dehydrogenases dependent on diphospho-pyridine nucleotide as described by Kato and coworkers (see p. 231). 

The toxicity of cord factor is of a delayed type five to ten micrograms kill adult mice within 5 to 8 days after injection. Repeated small doses are more toxic than a single large one. The cause of death is unknown extensive pulmonary hemorrhages are the most conspicuous symptom. ... 

Cord Factor Trehalose 6,6-dimycolaie 6.6 -di-0-mycolyl -a,a-trehalose (6-O-mycolyl -dr-D-glucopyranos-yl) 6-0 mycolyl-ot-D-glucopyranoside Toxic glycolipjds responsible for the cord formation and the leukotoxic effect of virulent bacilli. The term cord factor is widely used for the natural mixture of trehalose dimycolates produced by virulent Mycobacteria, Nocardia, Corynebacteria and attenuated BCG, q.v. For precise designation, the strain from which the preparation was isolated must be mentioned. First isolated from Mycobacterium tuberculosis H. Bloch, J. Exp. 

Pseudo cord factors have been prepared from a-D-glucopyranosyluronic acid-(ll)-a-D-glucopyranosyluronic acid as bis-amides and di-esters of intermediate to high molecular weight.The i.r. spectra of these compounds were similar to authentic cord factors. Several of the compounds had an impressive toxicity to mice and tumour-regression activity the latter does not depend on the former. 

Glycolipids and Gangliosides.—Approaches to the synthesis of D-galactosyl-glycerol, D-galactosyldiglycerides, and plant galactolipids have been reviewed. A new approach to the synthesis of cord factor (the toxic glycolipid of Mycobacterium tuberculosis) is based on the use of ester derivatives of aa-trehalose... 

Yarkoni E, Rapp HJ. 1978. Toxicity of emulsified trehalose-6,6 -dimycolate (cord factor) in mice depends on size distribution of mineral oil droplets. Infect Immun 20(3) 856-860. 

Isoniazid (INH) and Derivatives — Various haloisonicotinic acid derivatives were prepared and tested in vitro by Palat and coworkers. X was most active against the human strain %yRv, XI was most active against an INH resistant avian strain. Bekierkunst determined that INH affects nicotinamide metabolism and protects mice treated with cord factor (a toxic extract of tubercle bacillus). He discussed these results and proposed a mode of action of INH in tuberculous infections. " ... 

An interesting approach postulates that angiogenic growth factors such as platelet-derived growth factor, insulin-like growth factor-1, and vascular endothelial growth factor lead to reduced long-term toxicity in the spinal cord in pre-chnical studies in a spinal-cord irradiation rat model (Andratschke et al. 2005). 

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