Research progress on major pharmacological activities of S-allyl-L-cysteine / 国际生物医学工程杂志

Oxidation and inflammation are associated with the pathological processes of most human diseases, posing a serious threat to human health. In recent years, researchers have extracted monomeric compounds from natural products for the prevention and treatments of diseases related to oxidation and inflammation. That has become a major trend in the study of anti-oxidant and anti-inflammatory drugs. Garlic, a natural product, has pharmacological activities such as anti-tumor, anti-inflammatory and detoxification and so on. Therefore, it is important to study and extract the active ingredients in garlic. As an active ingredient extracted from garlic, S-allyl-L-cysteine (SAC) has been extensively studied in cell and animal models. The main pharmacological activities of SAC and the related receptors were reviewed, and its mechanism of action in vivo and the beneficial effects on the corresponding diseases were summarized to provide the necessary basis for further study.

PMK-S005 Alleviates Age-Related Gastric Acid Secretion, Inflammation, and Oxidative Status in the Rat Stomach

BACKGROUND/AIMS: The aim of this study was to evaluate the effect of the synthetic S-allyl-l-cysteine (SAC) PMK-S005 on gastric acid secretion, inflammation, and antioxidant enzymes in aging rats. METHODS: The rats were divided into four groups at 31 weeks of age and were continuously fed a diet containing a vehicle control, PMK-S005 (5 or 10 mg/kg), or lansoprazole (5 mg/kg). Gastric acid secretion and connective tissue thickness of the lamina propria were evaluated at 74 weeks and 2 years of age. Tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and COX-2 levels were measured by using enzyme-linked immunosorbent assays (ELISAs) or Western blot assays. Levels of antioxidant enzymes, including heme oxyganase 1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO-1), were also measured. RESULTS: As the rats aged, gastric acid secretion significantly decreased, and the connective tissue of the lamina propria increased. However, 74-week-old rats in the PMK-S005 group exhibited greater levels of gastric acid secretion than those of the control and lansoprazole groups. The increase of TNF-α, IL-1β, and COX-2 expression in 74-week and 2-year-old control rats were inhibited by PMK-S005. In addition, the decrease in HO-1 and NQO-1 protein expression that occurred with aging was inhibited by PMK-S005 in the 74-week-old rats. CONCLUSIONS: These results suggest that PMK-S005 has therapeutic potential as an antiaging agent to ameliorate age-related gastric acid secretion, inflammation, and oxidative stress in the stomach.

Gastroprotective Effects of PMK-S005 against Ethanol-Induced Acute Gastric Damage in Rats

BACKGROUND/AIMS: This study aimed to examine the gastroprotective effects of PMK-S005, which is a synthetic S-allyl-L-cysteine (SAC; a sulfur-containing amino acid), against acute ethanol-induced gastric damage in rats. METHODS: Sprague-Dawley rats were divided into six groups, including a nonethanol group, groups treated with absolute ethanol 1 hour after pretreatment with various doses of PMK-S005 (1, 5, and 10 mg/kg) or rebamipide (50 mg/kg), and an absolute ethanol-only group. Ethanol-induced gross ulcer and mucus levels were measured. Myeloperoxidase, tumor necrosis factor α, interleukin 1β, PGE2, LTB4, cPLA2, COX-1, and COX-2 levels were estimated by enzyme-linked immunosorbent assay or Western blot analysis. Furthermore, the protein expression levels of antioxidant enzymes, including heme oxygenase-1 (HO-1), NAD(P)H:quinine oxidoreductase 1 (NQO-1), GCLC, and GCLM, were assessed. RESULTS: PMK-S005 significantly attenuated the ethanol-induced gastric damage; it reduced mucosal inflammatory cytokine production and increased mucus levels. The expression levels of cPLA2, COX-1, and COX-2 were decreased by PMK-S005. PMK-S005 did not affect PGE2 synthesis, but LTB4 production was significantly suppressed. In addition, long-term administration of PMK-S005 significantly increased the expression of HO-1, NQO-1, GCLC, and GCLM. CONCLUSIONS: These results strongly suggest that PMK-S005 prevents gastric mucosal damage and that these gastroprotective activities are due to anti-inflammatory effects and enhancement of the gastric defense system, including antioxidant enzymes.