1.Neuroprotective effect of S-allyl-l-cysteine derivatives against endoplasmic reticulum stress-induced cytotoxicity is independent of calpain inhibition.
Imai T1, Kosuge Y1, Saito H2, Uchiyama T2, Wada T3, Shimba S3, Ishige K1, Miyairi S2, Makishima M4, Ito Y5. J Pharmacol Sci. 2016 Mar;130(3):185-8. doi: 10.1016/j.jphs.2016.03.004. Epub 2016 Mar 14.
S-allyl-l-cysteine (SAC) is known to have neuroprotective properties. We synthesized various SAC derivatives and tested their effects on endoplasmic reticulum stress-induced neurotoxicity in cultured hippocampal neurons (HPNs). Among the compounds tested, S-propyl-l-cysteine (SPC) exhibited the strongest neuroprotective activity in HPNs, followed by S-ethyl-l-cysteine (SEC) and S-methyl-l-cysteine (SMC). Unlike SAC and SMC, SPC and SEC did not have inhibitory activity on μ-calpain, suggesting that the mechanism underlying the protective activity of SPC and SEC differs from that of SAC.
2.Effective production of S-allyl-L-cysteine through a homogeneous reaction with activated endogenous γ-glutamyltranspeptidase in garlic (Allium Sativum).
Xu X1, Miao Y1, Chen JY2, Zhang Q1, Wang J3. J Food Sci Technol. 2015 Mar;52(3):1724-9. doi: 10.1007/s13197-013-1138-0. Epub 2013 Aug 16.
S-allyl-L-cysteine (SAC) is a bioactive compound in garlic (Allium sativum). A novel process including soaking and homogeneous reaction was applied for the effective production of SAC with endogenous γ-glutamyltranspeptidase (γ-GTP, EC 22.214.171.124) in garlic. The effects of temperature and CaCl2 concentration on γ-GTP activity in soaking, and the relationship of SAC production with γ-GTP activity in homogeneous reaction were investigated, using fresh garlic as raw material. The experimental results showed that the γ-GTP in fresh garlic was activated by soaking. The yield rate and the final content of SAC increased linearly with increasing initial γ-GTP activity in the homogeneous reaction at 37 °C. The final SAC content reached 606.3 μg/g (i.e. 32 times higher than that in fresh garlic) after soaking for 72 h in a 10-mM CaCl2 solution at 10 °C, and the homogeneous reaction for 8 h at 37 °C. SAC was produced effectively through the homogeneous reaction with activated endogenous γ-GTP in garlic.
3.Pharmacokinetics of S-Allyl-l-cysteine in Rats Is Characterized by High Oral Absorption and Extensive Renal Reabsorption.
Amano H1, Kazamori D2, Itoh K2. J Nutr. 2016 Feb;146(2):456S-9S. doi: 10.3945/jn.114.201749. Epub 2016 Jan 13.
BACKGROUND: S-Allylcysteine (SAC) is a key component of aged garlic extract, one of many garlic products. However, information on its pharmacokinetics has been scant except for data from a few animal studies.
4.Metabolism, excretion, and pharmacokinetics of S-allyl-L-cysteine in rats and dogs.
Amano H1, Kazamori D2, Itoh K2, Kodera Y2. Drug Metab Dispos. 2015 May;43(5):749-55. doi: 10.1124/dmd.115.063230. Epub 2015 Feb 13.
The metabolism, excretion, and pharmacokinetics of S-allyl-l-cysteine (SAC), an active key component of garlic supplements, were examined in rats and dogs. A single dose of SAC was administered orally or i.v. to rats (5 mg/kg) and dogs (2 mg/kg). SAC was well absorbed (bioavailability >90%) and its four metabolites-N-acetyl-S-allyl-l-cysteine (NAc-SAC), N-acetyl-S-allyl-l-cysteine sulfoxide (NAc-SACS), S-allyl-l-cysteine sulfoxide (SACS), and l-γ-glutamyl-S-allyl-l-cysteine-were identified in the plasma and/or urine. Renal clearance values (<0.01 l/h/kg) of SAC indicated its extensive renal reabsorption, which contributed to the long elimination half-life of SAC, especially in dogs (12 hours). The metabolism of SAC to NAc-SAC, principal metabolite of SAC, was studied in vitro and in vivo. Liver and kidney S9 fractions of rats and dogs catalyzed both N-acetylation of SAC and deacetylation of NAc-SAC. After i.v. administration of NAc-SAC, SAC appeared in the plasma and its concentration declined in parallel with that of NAc-SAC.