Antioxidative activity of sulfur-containing compounds in Allium species for human LDL oxidation in vitro

Effects of onion extract containing concentrated cysteine sulfoxides on sleep quality: a randomized, double-blind, placebo-controlled, crossover study

The objective of this randomized, double-blind, placebo-controlled, crossover study was to examine the effects of onion extract containing concentrated cysteine sulfoxides on improving sleep quality. In total, 30 healthy men and women who were dissatisfied with their sleep consumed the test food sample (onion extract tablets) for 5 days. The delta power during non-rapid eye movement sleep and the delta power per minute in the first sleep cycle increased significantly with the intake of onion extract containing concentrated cysteine sulfoxides compared with the intake of placebo. A significant decline in sleep latency was also observed. Salivary α-amylase level, a stress indicator, decreased significantly with the intake of onion extract containing concentrated cysteine sulfoxides compared with the intake of placebo. These findings indicate that onion extract containing concentrated cysteine sulfoxides alleviates stress, improves the quality of sleep and promotes smooth transition into sleep.

Cysteine Sulfoxides Enhance Steroid Hormone Production via Activation of the Protein Kinase A Pathway in Testis-Derived I-10 Tumor Cells

Testosterone plays an important role in male sexual characteristics and maturation, and decreased testosterone levels increase the risk of several diseases. Recently, onion extract rich in cysteine sulfoxides, which are amino acids unique to onions, has been reported to alleviate age-related symptoms resulting from decreased testosterone levels in males. However, the mechanism underlying the suppression of low testosterone levels by cysteine sulfoxides has not been elucidated. In this study, we found that onion extract containing cysteine sulfoxides enhanced progesterone, a precursor of testosterone, in mouse testis-derived I-10 tumor cells. Furthermore, cysteine sulfoxides activated protein kinase A (PKA) and cyclic adenosine monophosphate response element-binding protein, which are key factors in steroidogenesis. These results suggest that cysteine sulfoxides enhance steroid hormone production via activation of the PKA signaling pathway.

Structure, Antioxidant and Anti-inflammatory Activities of the (4R)- and (4S)-epimers of S-Carboxymethyl-L-cysteine Sulfoxide

S-Carboxymethyl-L-cysteine (CMC) is an antioxidant and mucolytic commonly prescribed to patients with chronic obstructive pulmonary disease. In humans, CMC is rapidly metabolized to S-carboxymethyl-L-cysteine sulfoxide (CMCO). In this study, we assessed structural and functional similarities between CMC and CMCO. X-Ray diffraction analysis provided detailed structural information about CMCO, which exists as a 1:1 mixture of epimers, due to the emergence of a new chiral center at the sulfur atom. Both CMC and CMCO epimers protected model DNA from copper-mediated hydroxyl free radical damage. Using an insulated transposable construct for reporting activity of the cellular stress-responsive transcription factors Nrf2, p53, NF-κB, and AP-1, we demonstrate that CMCO, especially its (4R)-epimer, is comparable to CMC in their ability to mitigate the effects of oxidative stress and pro-inflammatory stimuli in human alveolar (A549) and bronchial epithelial (BEAS-2B) cells. The results of these in vitro studies suggest that CMCO retains, at least partially, the antioxidant potential of CMC and may inform pharmacodynamics considerations of CMC use in clinics.

Attenuated Renal and Hepatic Cells Apoptosis Following Swimming Exercise Supplemented with Garlic Extract in Old Rats

Background/Objective

One of the problems associated with aging is the development of apoptosis in different tissues. There is evidence that physical activity and herbal remedies can be useful. This study aimed to determine the effect of swimming training (SW) alone or combined with garlic extract on renal and hepatic cells apoptosis, as wellas on the liver and kidney function biomarkers in old rats.

Methods

A total of 35 old rats (aged 40–50 weeks) were randomly divided into 5 groups including control, saline (S), exercise training (ET), garlic (G) and exercise training+ garlic (ET.G) groups. Exercise was started for 5 min/day and then gradually extended to 60 min/day and the G and E+G groups received 1 mL/kg of this mixture by gavage. Twenty-four hours after completion of 8 weeks training, liver, kidney and blood samples were collected for histopathological examinations, liver and kidney functions, oxidative stress and apoptosis biomarkers.

Results

The tissue sections of the SW exercise, control and saline groups showed some mild histopathological changes in liver and kidney, while SW supplemented with garlic prevented these damages. The SW alone or supplemented with garlic significantly increased the Bcl-2 value and declined the BAX level in both liver and kidney (p<0.05). The activities of catalase (CAT) and superoxide dismutase (SOD) in the liver and kidney of the control and saline groups were lower than those in E, G and G+E groups, while a significant increase for malondialdehyde (MDA) value was found in the control and saline groups. Furthermore, the E+G significantly declined the activity of hepatic (ALT, AST and ALP) and renal damage (uric acid, urea and creatinine) biomarkers compared to the control and saline groups (p<0.05).

Discussion

Swimming exercise supplemented with garlic extract not only improves antioxidant capacity but also declines oxidative damages and apoptosis through reducing Bax levels and enhancing Bcl-2 value.

Hairy Garlic (Allium subhirsutum) from Sicily (Italy): LC-DAD-MSn Analysis of Secondary Metabolites and In Vitro Biological Properties

Allium subhirsutum, known as hairy garlic, is a bulbous plant widespread in the Mediterranean area and locally used as a food and spice. In the present study, the chemical profile of the ethanolic extracts from bulbs (BE) and aerial parts (APE) were analyzed by HPLC-ESI-MSⁿ, and antioxidant properties were evaluated by DPPH, ABTS and TEAC assays. The traditional use in the diet, and the well documented biological activity of Allium species suggest a potential as a new nutraceutical. For this reason, the potential usefulness of this food can be considered in the treatment and prevention of degenerative Alzheimer disease. For this reason, acetylcholinesterase inhibitory property was investigated. Furthermore, due to the observed presence of sulfur-containing and phenolic constituents, the cytotoxicity on tumor cells line was investigated. Results revealed significant AChE inhibitory activity for BE and APE. Both extracts exhibited also moderate antioxidant properties in the in vitro assays. Finally, limited cytotoxic activity was observed towards Human colon carcinoma and adenocarcinoma cell line, with differences between the individual parts tested. HPLC-ESI-MSⁿ analysis showed that hairy garlic is a good source of sulphur compounds, flavonoids and phenylpropanoids derivatives, thus being a valid alternative to the common garlic (A. sativum). This work opens new opportunities for the application of A. subhirsutum as a health-promoting food.

Combination effect of voluntary exercise and garlic (Allium sativum) on oxidative stress, cholesterol level and histopathology of heart tissue in type 1 diabetic rats

Introduction: This study aimed to evaluate the combination effect of voluntary exercise and garlic on oxidative markers, cholesterol level and histological alterations in streptozotocin (STZ)- induced diabetes in rat heart.

Methods: Thirty-five male Wistar rats were randomly assigned into five experimental groups (n=7): Control, Diabetes, Diabetes+Garlic, Diabetes+Exercise, Diabetes+Garlic+Exercise groups. Diabetes was induced by STZ (ip, 50 mg/kg) in animals. Animals received garlic homogenate (250 mg/kg) by oral gavage or subjected to voluntary exercise alone or together for 6 weeks. At the end of intervention blood and heart tissue samples were obtained and used for measurement of glycosylated haemoglobin (HbA1c), cholesterol, total antioxidant capacity (TAC), malondialdehyde (MDA) levels and histological analysis.

Results: Improved blood glucose, cholesterol, total antioxidant capacity, and MDA levels were established in both Diabetes+Garlic and Diabetes+Exercise groups. Additionally, staining with Hematoxylin and Eosin (H&E) revealed that voluntary exercise and garlic alone and together reduced interstitial edema, leukocyte infiltration, and myonecrosis. Furthermore, simultaneous treatment of diabetic rats with garlic and exercise training had an additive effect on these parameters.

Conclusion: The findings indicated that combination therapy with garlic and voluntary exercise may present more beneficial effects in heart histological remodeling in diabetic rats than the use of garlic or voluntary exercise alone and that these beneficial effects might be associated with enhancement in cholesterol, total antioxidant capacity, and MDA levels.

Biological activities of Zn(II)-S-methyl-cysteine complex as antiradical, inhibitor of acid phosphatase enzyme and in vivo antidepressant effects

The antidepressant effect of simple Zn(II) salts has been proved in several animal models of depression. In this study, a coordination metal complex of Zn(II) having a sulfur containing ligand is tested as antidepressant for the first time. Forced swimming test method on male Wistar rats shows a decrease in the immobility and an increase in the swimming behavior after treatment with [Zn(S-Met)2] (S-Met=S-methyl-l-cysteine) being more effective and remarkable than ZnCl2. The thiobarbituric acid and the pyranine consumption (hydroxyl and peroxyl radicals, respectively) methods were applied to evaluate the antioxidant activity of S-Met and [Zn(S-Met)2] showing evidence of attenuation of hydroxyl but not peroxyl radicals activities. UV-vis studies on the inhibition of acid phosphatase enzyme (AcP) demonstrated that S-methyl-l-cysteine did not produce any effect but, in contrast, [Zn(S-Met)2] complex behaved as a moderate inhibitor. Finally, bioavailability studies were performed by fluorescence spectroscopy denoting the ability of the albumin to transport the complex.

Antioxidant action and therapeutic efficacy of Allium sativum L

Allium sativum (L.) is rich in antioxidants which help destroy free radicals particles that can damage cell membranes and DNA, and may contribute to the aging process as well as the development of a number of conditions, including heart disease and cancer. Antioxidants neutralize free radicals and may reduce or even help prevent some of the damage they cause over time. The antioxidant activity of fresh Allium sativum L. (garlic) is well known and is mainly due to unstable and irritating organosulphur compounds. Fresh garlic extracted over a prolonged period (up to 20 months) produces odourless aged garlic extract (AGE) containing stable and water soluble organosulphur compounds that prevent oxidative damage by scavenging free radicals. The aim of this review was to understand the mechanism of antioxidant action and therapeutic efficacy of garlic.

1,2-vinyldithiin from garlic inhibits differentiation and inflammation of human preadipocytes

Obesity is a state of chronic low-grade inflammation. Limiting white adipose tissue (WAT) expansion and therefore reducing inflammation could be effective in preventing the progression of obesity and the development of associated complications. We investigated the effects of 1,2-vinyldithiin (1,2-DT), a garlic-derived organosulfur, on the differentiation and inflammatory state of human preadipocytes. Preadipocytes were prepared from subcutaneous adipose tissue of nonobese young women and differentiated in the presence of 1,2-DT. Inflammatory preadipocytes were obtained following treatment with human macrophage-secreted factors. 1,2-DT (100 micromol/L) significantly reduced gene expression of PPARgamma2 (-40%), CCAAT/enhancer binding protein-alpha (-25%), lipoprotein lipase (-22%), leptin (-30%), and adiponectin (-15%). Lipid accumulation was also significantly diminished in preadipocytes differentiated in the presence of 100 micromol/L 1,2-DT (-37%) compared with controls. Furthermore, 100 micromol/L 1,2-DT treatment for 10 d significantly reduced PPARgamma activity (-27%). The protein expression of perilipin and the secretion levels for 2 adipokines, leptin and adiponectin, were significantly diminished in 1,2-DT-cultured preadipocytes (-37, -51, and -43%, respectively). Moreover, the secretion of inflammatory molecules (interleukin-6 and monocyte chemoattractant protein-1) induced by macrophage-secreted factors was partially abolished in 100 micromol/L 1,2-DT-treated preadipocytes (-28 and -25%, respectively). In conclusion, we demonstrated that 1,2-DT, a garlic-derived organosulfur, has antiadipogenic and antiinflammatory actions on human preadipocytes and may be a novel, antiobesity nutraceutical.

S-allylcysteine scavenges singlet oxygen and hypochlorous acid and protects LLC-PK1 cells of potassium dichromate-induced toxicity

It has been found that S-allylcysteine (SAC), a garlic-derived compound, has in vivo and in vitro antioxidant properties. In addition, it is known that SAC is able to scavenge different reactive oxygen or nitrogen species including superoxide anion (O(2)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radical (OH()), and peroxynitrite anion (ONOO(-)) although the IC(5O) values for each reactive species has not been calculated and the potential ability of SAC to scavenge singlet oxygen ((1)O(2)) and hypochlorous acid (HOCl) has not been explored. The purposes of this work was (a) to explore the potential ability of SAC to scavenge (1)O(2) and HOCl, (b) to further characterize the O(2)(-), H(2)O(2), OH(), and ONOO(-) scavenging ability of SAC by measuring the IC(50) values using in vitro assays, and (c) to explore the potential ability of SAC to ameliorate the potassium dichromate (K(2)Cr(2)O(7))-induced cytotoxicity in LLC-PK1 cells in which oxidative stress is involved. The scavenging activity was compared against the following reference compounds: N-acetylcysteine for O(2)(-), sodium pyruvate for H(2)O(2), dimethylthiourea for OH(), lipoic acid and glutathione for (1)O(2), lipoic acid for HOCl, and penicillamine for ONOO(-). It was found that SAC was able to scavenge concentration-dependently all the species assayed with the following IC(5O) (mean+/-SEM, mM): O(2)(-) (14.49+/-1.67), H(2)O(2) (68+/-1.92), OH() (0.68+/-0.06), (1)O(2) (1.93+/-0.27), HOCl (2.86+/-0.15), and ONOO(-) (0.80+/-0.05). When the ability of SAC to scavenge these species was compared to those of the reference compounds it was found that the efficacy of SAC (a) to scavenge O(2)(-), H(2)O(2), OH(), and ONOO(-) was lower, (b) to scavenge HOCl was similar, and (c) to scavenge (1)O(2) was higher. In addition, it was found that SAC was able to prevent K(2)Cr(2)O(7)-induced toxicity in LLC-PK1 cells in culture. It was showed for the first time that SAC is able to scavenge (1)O(2) and HOCl and to ameliorate the K(2)Cr(2)O(7)-induced toxicity.

Evaluation of antioxidative properties ofAllium species growing wild in Italy

The genus Allium (Alliaceae) is an important dietary source of antioxidant phytochemical products. The antioxidant activity of some Allium species is well known but no information is available on the in vitro antioxidant activities of Italian Allium species growing wild. The aim of this study was to examine the in vitro antioxidant activity of aqueous extracts of different parts belonging to three Allium species growing wild, endemic to Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L. and Allium roseum L., compared with the in vitro antioxidant activity of aqueous extracts of bulbs and leaves of the greatly studied garlic (Allium sativum L.). The antioxidant potential of extracts was evaluated using two different spectrophotometric assays: the DPPH test and FRAP assay. Furthermore the polyphenolic content was determined in all Allium species. The flowers of species growing wild showed the higher antioxidant power. Interesting results were shown even by the leaves, while the antioxidant capacity of the bulbs was lower. A correlation between the phenolic contents and the antioxidant activity was discovered. The differences in antioxidant capacity reflect the variability in the Allium species and the parts of the plant used and that the bulb of Allium sativum did not show higher antioxidant power.