Insulinotropic Effect of S-Allyl Cysteine in Rat Pups

Neonatal Orally Administered Zingerone Attenuates Alcohol-Induced Fatty Liver Disease in Experimental Rat Models

Alcohol intake at different developmental stages can lead to the development of alcohol-induced fatty liver disease (AFLD). Zingerone (ZO) possess hepato-protective properties; thus, when administered neonatally, it could render protection against AFLD. This study aimed to evaluate the potential long-term protective effect of ZO against the development of AFLD. One hundred and twenty-three 10-day-old Sprague-Dawley rat pups (60 males; 63 females) were randomly assigned to four groups and orally administered the following treatment regimens daily during the pre-weaning period from postnatal day (PND) 12-21: group 1-nutritive milk (NM), group 2-NM +1 g/kg ethanol (Eth), group 3-NM + 40 mg/kg ZO, group 4-NM + Eth +ZO. From PND 46-100, each group from the neonatal stage was divided into two; subgroup I had tap water and subgroup II had ethanol solution as drinking fluid, respectively, for eight weeks. Mean daily ethanol intake, which ranged from 10 to 14.5 g/kg body mass/day, resulted in significant CYP2E1 elevation (p < 0.05). Both late single hit and double hit with alcohol increased liver fat content, caused hepatic macrosteatosis, dysregulated mRNA expression of SREBP1c and PPAR-α in male and female rats (p < 0.05). However, neonatal orally administered ZO protected against liver lipid accretion and SREBP1c upregulation in male rats only and attenuated the alcohol-induced hepatic PPAR-α downregulation and macrosteatosis in both sexes. This data suggests that neonatal orally administered zingerone can be a potential prophylactic agent against the development of AFLD.

Prophylactic Use of Natural Products against Developmentally Programmed Metabolic Syndrome

Parental dietary choices and/or nutritional interventions in the offspring are critical to early life development, especially during the periods of active developmental plasticity in the offspring. Exposure to a high-fructose, high-fat diet during the fetal or neonatal period predisposes the affected individuals to the development of one or more features of metabolic syndrome, such as dyslipidemia, insulin resistance, diabetes, and associated cardiovascular diseases, later in their life. Owing to the increasing global prevalence of metabolic syndrome and multiple side effects that accompany conventional medicines, much attention is directed towards medicinal plants and phytochemicals as alternative interventions. Several studies have investigated the potential of natural agents to prevent programmed metabolic syndrome. This present review, therefore, highlights an inextricable relationship between the administration of medicinal plants or phytochemicals during the intrauterine or neonatal period, and the prevention of metabolic dysfunction in adulthood, while exploring the mechanisms by which they exert such an effect. The review also identifies plant products as a novel approach to the prevention and management of metabolic syndrome.

S-Allyl cysteine in garlic (Allium sativum): Formation, biofunction, and resistance to food processing for value-added product development

S-allyl cysteine (SAC), which is the most abundant bioactive compound in black garlic (BG; Allium sativum), has been shown to have antioxidant, anti-apoptotic, anti-inflammatory, anti-obesity, cardioprotective, neuroprotective, and hepatoprotective activities. Sulfur compounds are the most distinctive bioactive elements in garlic. Previous studies have provided evidence that the concentration of SAC in fresh garlic is in the range of 19.0-1736.3 μg/g. Meanwhile, for processed garlic, such as frozen and thawed garlic, pickled garlic, fermented garlic extract, and BG, the SAC content increased to up to 8021.2 μg/g. BG is an SAC-containing product, with heat treatment being used in nearly all methods of BG production. Therefore, strategies to increase the SAC level in garlic are of great interest; however, further knowledge is required about the effect of processing factors and mechanistic changes. This review explains the formation of SAC in garlic, introduces its biological effects, and summarizes the recent advances in processing methods that can affect SAC levels in garlic, including heat treatment, enzymatic treatment, freezing, fermentation, ultrasonic treatment, and high hydrostatic pressure. Thus, the aim of this review was to summarize the outcomes of treatment aimed at maintaining or increasing SAC levels in BG. Therefore, publications from scientific databases in this field of study were examined. The effects of processing methods on SAC compounds were evaluated on the basis of the SAC content. This review provides information on the processing approaches that can assist food manufacturers in the development of value-added garlic products.

S-allyl cysteine ameliorates heat stress-induced oxidative stress by activating Nrf2/HO-1 signaling pathway in BMECs

Heat stress-induced oxidative stress in bovine mammary epithelial cells (BMECs) threatens the normal growth and development of bovine mammary tissue, resulting in lower milk production of dairy cows. The aim of the present study is to investigate the protective effects of S-allyl cysteine (SAC), an organosulfur component extracted from aged garlic, on heat stress-induced oxidative stress and apoptosis in BMECs and to explore its underlying mechanisms. Our results showed that heat stress treatment considerably decreased cell viability, whereas SAC treatment dose-dependently restored cell viability of BMECs under heat-stress conditions. In addition, SAC protected BMECs from heat stress-induced oxidative damage by inhibiting the excessive accumulation of reactive oxygen species (ROS) and increasing the activity of antioxidant enzymes. It also inhibited heat stress-induced apoptosis by reducing the ratio of Bax/Bcl-2 and blocking proteolytic the cleavage of caspase-3 in BMECs. Interestingly, we found that the protective effect of SAC on heat stress-induced oxidative stress and apoptosis was dependent on the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. SAC promoted the Nrf2 nuclear translocation in heat stress-induced BMECs. The results were also validated by Nrf2 and Keap1 knockdown experiments further demonstrating that Nrf-2 was indeed involved in the protective effect of SAC on heat stress-induced oxidative damage and apoptosis. In summary, our results showed that SAC could protect BMECs from heat stress-induced injury by mediating the Nrf2/HO-1 signaling pathway, suggesting that SAC could be considered as a therapeutic drug for attenuating heat stress-induced mammary gland diseases.