X. KFFKCTS (IK DKKK 1 M.NCJY G07 



of \itamins tVoin the diet. I'lirtlicc. I he same authors lia\(' also shown (a) 

 that l)iotiii will not rctitilai'lx' ])i'o(hic(' t'att\- liNcr, (h) IJiat it' tatty Vw'vv 

 develops thei'c is no sclectix'e deposition of cholestei'ol esters in the li\-ei\ 

 (c) that inositol has no specihc effect on i)ound cholesterol, and (d) that 

 the fatt\' lixcr ohsci'X'ed when hiotin is administered is by no means resis- 

 tant to choline 'I'he (>lTect of inositol is synei-gislic to that of choline, the 

 latter hein^- the "piimarv" and more effective lipotropic agent. K\v\) aftei- 

 administration of hiotin the usual constant relat ionsliip between the aecu- 

 mulation of cholesterol esters and tlie deposition of neutral fat in the liver 

 remains unchanjiCHl. Rest and his associatf^s*^'- ha\'e found no e\'idenee of 

 any specific effect of choline, inositol, and hiotin on the al)solute amount 

 of free cholesterol or phospholipids in the li\'er, and they I'ecommended 

 iu the lioht of all their pertinent findings that the term "hiotin fatty li\'er" 

 he abandoned. 



The role of biotiu in fat metabolism and indirectly the problem of "biotin 

 fatty liver" has been recently revived by Okey and her associates. ^^ ^^ Rats 

 fed a diet moderately rich iu egg white or dried whole egg (avidin) will 

 develop a mild degree of biotiu deficiency, characterized among other 

 specific manifestations of the deficiency condition l\v a reduced content of 

 fat and in ])ai'ticular by that of cholesterol in the liver. In severe stages of 

 the deficiency the fat depots of the subcutaneous tissue and of all the viscera 

 will rapidly disapi)ear. Addition of ])iotin to the diet will lead to reacctunu- 

 lation of fat in the fat depots and in the Ywvv. In cases of mild biotiu defi- 

 ciency the reappearance of fat in the liver after administration of hiotin 

 maj^ be observed without any significant change in food intake. In rats fed 

 experimental lations enriched in cholesterol (through dried whole egg or 

 cholesterol added to egg white) and suppl(niient(Hl with ample biotin, the 

 liver fatty acid values were one and one-half to three times, and total liver 

 cholesterol values six to eight times, as high as those of rats fed similar 

 adef[uatc cholesterol-free diets. Most of the increase in cholesterol was in 

 the esterified fraction. The same rations, low in biotin, I'ich in cholesterol, 

 and without extra supplements of biotin, will not support storage of fat or 

 cholesterol in the li\er. 



Avidin given with the diet will effect i\('l>' pre\ent the deposition of 

 excess cholesterol in the li\('i-. In contrast, no definite indication was ob- 

 tained"^ for a "therapeutic" effect of a\idin, i.e., for the disappearance of 

 cholesterol stores in the li\ei-, which were accumulated prioi- to the ad- 

 ministration of a\idin. 



In \'iew of the fact that in biotin deficiency cholesterol estei's show a 



M R. Okey, ./. liiul. Clicm. 165, 3s:i (HIKi). 



6' R. Okey, R. Pencharz, and S. L('i)kovsl<y. Am. ./. J'ln/siol. 161, 1 (IdSO). 



«^ R. ()l<oy, R. IViicli.nv., S. b('i)i<ovsky. an.! K. R. X'criioii, ./. Xiilritian 44, S3 (19.51 ). 



