1 / 11

Study of in vivo Diallyl disulfide Metabolism

Study of in vivo Diallyl disulfide Metabolism. Aims of the study : To determine the pharmacokinetic parameters of DADS To determine the metabolites of DADS : bio-availability of DADS and of the metabolites Experimental conditions in rat DADS administrated by force feeding

tadhg
Download Presentation

Study of in vivo Diallyl disulfide Metabolism

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Study of in vivo Diallyl disulfide Metabolism • Aims of the study : • To determine the pharmacokinetic parameters of DADS • To determine the metabolites of DADS : bio-availability of DADS and of the metabolites • Experimental conditions • in rat • DADS administrated by force feeding • Analysis instruments :  DADS , AM, AMS, AMSO, AMSO2 : volatile compounds studied by GC-MS (gas chromatography mass spectrometry) and quantified by using the technique of Selected Ion Monitoring (SIM) AGS: non-volatile compounds studied by HPLC-UV (254nm) 4th October 2001

  2. Metabolism in vitro of DADS O S O AMSO2 , Allylmethylsulfone O S S S DADS, diallyldisulfide AMSO, allyl methyl sulfoxide S Allyl methyl sulfur SH AM, Allyl mercaptan O S S S-glutathion S DADSO, allicin AGS, Allylglutathionylsulfure 4th October 2001

  3. Method and experimental protocol DADS i.g. 200 mg/kg • Sacrifice • 0.15, 0.3, 0.6, 1, 2, 4, 6, 24 hours • every single days during 2 weeks. Plasma Urine Kidney Intestine Stomach Liver • Sample preparation • homogenization, p cymene (internal standard) • protein precipitation (TCA, 30%) • Extraction with CH2Cl2(3 times) • organic phase : nonane (standardization for concentration) GC-MS analysis 4th October 2001

  4. General Observations • Toxicity: • 8% toxicity(4/52 of treated rats dead during the first 24 hours) • Evaluation of GC-MS analytical procedures • Minimum detection : AM=1 E-4µg/ml AMS=8E- 4µg/ml DADS=1E-3µg/ml • Linearity : AM =7.E-3µg/ml -100µg/ml, AMS=3 E-3µg/ml - 87µg/ml DADS= 3 E-3µg/ml - 110µg/ml • Quantitative analysis of sulfur compounds levels performed by integrating standards levels (GC-MS) sulfur compounds • u.a g-1 = p cymene X nonane X organ weight • No DADSO detected in liver and plasma extracts • No AGS in liver extracts HPLC-UV 4th October 2001

  5. Repartition of DADS stomach = 20 000ua.g-1 Early (<24 hours) 1- Detected in each organ 2- Maximum in liver Long-time (<15 days) 1- Quantifiable in stomach and in intestine until the 3rd day 2- Very low levels in other organs 4th October 2001

  6. Metabolites in plasma 1- Early 2- long time - Very low levels of AM and AMS - Rapid appearance of AMSO and AMSO2(10 min.) - Peaks at the second day 4th October 2001

  7. Metabolites in liver 1- Early 2- long time - The highest level of AMS, AMSO and AMSO2 - Levels of AM, AMS, AMSO and AMSO2associated - Ratio AMSO2/AMSO : liver > plasma 4th October 2001

  8. Metabolites in stomach 1- Early 2- long time - Highest level of AM (vs other organs) - No association between all sulfur compounds levels - Essentially similar pattern in intestine 4th October 2001

  9. Metabolites in kidney 1- Early 2- long time - Similar to plasma (distribution or storage ?) 4th October 2001

  10. Metabolites in urine 1- Early 2- long time - Moderate levels of compounds (predominant way of elimination ?) - Complete elimination by the 11th day 4th October 2001

  11. Conclusions • Absolute quantification is required (purified oxidized compounds are now available) • Oral administration of DADS induces AM, AMS, AMSO, AMSO2formation • Confirmation of the in vitro hepatic metabolism. • But no DADSO and AGS are detectable • Two steps : • a rapid biotransformation and disappearance of DADS < 6 hours • a long period of elimination for oxidized metabolites <13 days • Perspectives • study of in vivo DADSO metabolism • implication of AGS 4th October 2001

More Related