Garlic and onions: their cancer prevention properties

Association between Allium vegetables and the risk of non-digestive tract cancer: A systematic review and meta-analysis of cohort and case-control studies

PURPOSE

To clarify the role of Allium vegetables in non-digestive tract cancer, we conducted this meta-analysis.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, we conducted a meta-analysis of published studies assessing the associations between Allium vegetables and the risk of non-digestive tract cancer. We estimated the pooled odds ratio (OR) of non-digestive tract cancer for the highest and lowest Allium vegetable consumption using random-effects models. A dose-response regression model was used to evaluate the relationship between Allium vegetables and non-digestive tract cancer risk.

RESULTS

In a pooled analysis of 25 studies (11 cohort and 14 case-control studies) on Allium vegetables, a total of 18,070 patients with non-digestive tract cancer were finally included. Integrated OR of non-digestive tract cancer was 0.86 [95% confidence interval (CI):0.80-0.93] for the highest versus the lowest Allium vegetable consumption for all studies, 0.78 (95% CI:0.69-0.90) for case-control studies and 0.94 (95%CI: 0.87-1.02) for cohort studies. Sensitivity analysis showed that the pooled effect was stable. No apparent publication bias was identified in this study; however, the cumulative meta-analysis suggested that studies conducted earlier (from 1994 to 1997) might be a source of heterogeneity. Dose-response regression model indicated that Allium vegetable consumption was associated with the risk of non-digestive tract cancer (P = 0.001 for non-linearity; P = 0.032 for linearity).

CONCLUSION

Higher Allium vegetable consumption could reduce the risk of non-digestive tract cancers, demonstrating the protective role of Allium vegetables.

Garlic (Allium sativum Linnaeus) improved inflammation and reduced cryptosporidiosis burden in immunocompromised mice

ETHNOPHARMACOLOGICAL RELEVANCE

For thousands of years, garlic (Allium sativum Linnaeus) has been consumed in food and health by numerous civilizations. Cryptosporidium (C.) parvum is an apicomplexan parasite that causes a gastrointestinal disease, with the most common symptoms being watery diarrhea. Although several substances have been tried for its anti-cryptosporidial action, there is no effective treatment for Cryptosporidium disease, especially in immunocompromised individuals. The present study aimed firstly to characterize the bio-active compounds in Allium sativum L. and secondly to evaluate its efficacy as a therapy for cryptosporidiosis especially in immunocompromised mice.

MATERIALS AND METHODS

This was accomplished by evaluating the parasitological and histopathological parameters in the experimentally infected immunocompetent and immunocompromised mice. Also, the cytokine profile during the experimental time was recorded through the measuring of T helper (h)1, Th2 and Th17 cells cytokines. Immunosuppressed mice were given 0.25 μg/g per day of dexamethasone orally, before infection with Cryptosporidium parvum oocysts, for fourteen consecutive days. Starting 10 days post infection (PI), nitazoxanide (100 mg/kg per day) or Allium sativum (50 mg/kg per day) was given orally for fourteen consecutive days.

RESULTS

Our results showed that oocyst shedding, on the 32nd day PI, in immunocompromised infected group treated with Allium sativum (354.11, 99.35% PR) showed a significant decrease when compared to its corresponding group treated with nitazoxanide (4369.14, 92.05% PR). On the 32nd day PI, all cytokines levels have been decreased to levels that were similar to those of their uninfected corresponding control groups; also, the histopathological changes and the loss in animals' body weight had been improved. Treatment with nitazoxanide did not result in infection clearance or a reduction in the increased cytokines' levels.

CONCLUSION

Allium sativum L. displayed high efficacy as a potential therapeutic agent against Cryptosporidium, which supports its traditional usage in parasite diseases.

S-allylcysteine potently protects against PhIP-induced DNA damage via Nrf2/AhR signaling pathway modulation in normal human colonic mucosal epithelial cells

SCOPE

This study aimed to investigate whether S-allylcysteine (SAC) exerts chemoprophylactic effects on foodborne carcinogenicity caused by 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in normal human colonic mucosal epithelial cells.

METHODS AND RESULTS

Cellular thermal shift assays showed that SAC had an affinity for the Keap1 protein. Moreover, SAC may also dampen the binding of Keap1 and NF-E2-related factor 2 (Nrf2) by inhibiting p-p38 and increasing the phosphorylation of ERK1/2 and AKT, thereby inducing Nrf2/HO-1 signaling and upregulating the ratio of GSH to GSH/GSSG, which inhibits PhIP-induced oxidative stress and DNA damage. In addition, SAC significantly downregulates the aryl hydrocarbon receptor signaling pathway, suggesting that SAC may potentially impede the metabolic transformation of carcinogens.

CONCLUSION

Collectively, these findings suggest that SAC protects against PhIP-induced reactive oxygen species production and DNA damage by modulating the Nrf2/AhR signaling pathway, which may have significant potential as a novel chemopreventive agent. This article is protected by copyright. All rights reserved.

Effects of Different Levels of Garlic Straw Powder on Growth Performance, Meat Quality, Antioxidant and Intestinal Mucosal Morphology of Yellow-Feathered Broilers

The full utilization of garlic straw can partially alleviate shortage of feedstuff and waste of resources. The purpose of this study was to investigate the effects of garlic straw as an unconventional feed on yellow-feathered broilers. 360 28-day-old yellow-feathered broilers were randomly divided into 4 groups with 6 replicates (cage) per group, 15 per cage. The 4 groups were as follows: control group (basal diet) and experimental group I (basal diet supplemented with 3% garlic straw powder), II (basal diet supplemented with 6% garlic straw powder) and III (basal diet supplemented with 9% garlic straw powder). There was no significant difference in the initial body weight of the broilers among groups (p > 0.05). The test period was 28 days in total. The experiment results showed that there were no significant difference in the average final weight, ADG, ADFI and F/G among groups (p > 0.05). On the one hand, for the breast muscle, the drip loss of experimental group I, II and III were reduced by 17.24% (p <0.05), 20.11% (p <0.05) and 20.50% (p <0.05), respectively, compared with the control group; the redness a* of the experimental groups had a trend of improvement (0.05 <p < 0.1). On the other hand, compared with the control group, the redness a* of the experimental group II increased significantly by 23.18% for the leg muscles (p < 0.05). Furthermore, compared with the control group, GSH-Px of the experimental group III significantly increased by 21.38% (p < 0.05), and SOD of the experimental group I significantly increased by 21.85% (p < 0.05). Finally, there were no significant differences in the intestinal villus height, crypt depth, V/C and intestinal wall thickness among four groups (p >0.05). In conclusion, dietary supplementation of different levels of garlic straw powder can improve meat quality and antioxidant capacity of yellow-feathered broilers without affecting growth performance and intestinal mucosal morphology.

Antioxidant Activity and Cytotoxicity of Aromatic Oligosulfides

Natural or synthetic antioxidants with biomimetic fragments protect the functional and structural integrity of biological molecules at a minimum concentration, and may be used as potential chemotherapeutic agents. This paper is devoted to in silico and in vitro evaluation of the antioxidant and cytotoxic properties of synthetic analogues of natural compounds—aromatic oligosulfides. The antiradical and SOD-protective activity of oligosulfides was demonstrated in the reaction with O₂^–• generated in enzymatic and non-enzymatic systems. It was found that phenol-containing disulfides significantly reduced the accumulation level of hydroperoxides and secondary carbonyl thiobarbituric acid reactive substances, which are primary products of oleic acid peroxidation. The antioxidant efficiency of bis(3,5-di-tert-butyl-4-hydroxyphenyl) disulfide increased over time due to the synergistic action of the 2,6-di-tert-butylphenol fragment and the disulfide linker. The highest cytotoxicity on the A-549 and HCT-116 cell lines was found for bis(3,4-dimethoxyphenyl) disulfide. Significant induction of apoptosis in HCT-116 cells in the presence of bis(3,4-dimethoxyphenyl) disulfide indicates the prospect of its use as an antitumor agent. The significant and moderate dependences revealed between various types of activities of the studied aromatic oligosulfides can be used in the development of a strategy for the synthesis and study of target-oriented compounds with predictable biological activity.

Allium vegetables intake and the risk of gastric cancer in the Stomach cancer Pooling (StoP) Project

BACKGROUND

The role of allium vegetables on gastric cancer (GC) risk remains unclear.

METHODS

We evaluated whether higher intakes of allium vegetables reduce GC risk using individual participant data from 17 studies participating in the "Stomach cancer Pooling (StoP) Project", including 6097 GC cases and 13,017 controls. Study-specific odds ratios (ORs) were pooled using a two-stage modelling approach.

RESULTS

Total allium vegetables intake was inversely associated with GC risk. The pooled OR for the highest versus the lowest study-specific tertile of consumption was 0.71 (95% confidence interval, CI, 0.56-0.90), with substantial heterogeneity across studies (I² > 50%). Pooled ORs for high versus low consumption were 0.69 (95% CI, 0.55-0.86) for onions and 0.83 (95% CI, 0.75-0.93) for garlic. The inverse association with allium vegetables was evident in Asian (OR 0.50, 95% CI, 0.29-0.86) but not European (OR 0.96, 95% CI, 0.81-1.13) and American (OR 0.66, 95% CI, 0.39-1.11) studies. Results were consistent across all other strata.

CONCLUSIONS

In a worldwide consortium of epidemiological studies, we found an inverse association between allium vegetables and GC, with a stronger association seen in Asian studies. The heterogeneity of results across geographic regions and possible residual confounding suggest caution in results interpretation.

Folic Acid and Chitosan-Functionalized Gold Nanorods and Triangular Silver Nanoplates for the Delivery of Anticancer Agents

Background

Advances in the field of nanotechnology have shed light on the applications of nanoparticles for cancer treatment.

Methods

Folic acid and chitosan-functionalized gold nanorods (FACS-R) and triangular silver nanoplates (FACS-T) were synthesized and their properties were elucidated by UV-visible spectrophotometry, Fourier-transform infrared spectroscopy, field emission transmission electron microscopy and high-resolution X-ray diffraction.

Results

The average size of the FACS-R was determined to be a transverse length of 13.1 ± 1.8 nm and a longitudinal length of 47.2 ± 8.9 nm with an aspect ratio of 3.6. The average size of FACS-T was measured to be 31.8 ± 7.7 nm. Colloidal solutions of FACS-R and FACS-T were stable on the shelf at ambient temperature for 14 days in the dark. Anticancer agents were encapsulated in FACS-R and FACS-T. FACS-T showed a higher encapsulation efficiency with docetaxel, paclitaxel and diallyl disulfide than FACS-R. The cell viability on human gastric adenocarcinoma cells (AGS), human epithelial cervix adenocarcinoma cells (HeLa) and human colorectal adenocarcinoma cells (HT-29) after treatment with anticancer agent-encapsulated FACS-R and FACS-T was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Interestingly, paclitaxel-encapsulated FACS-R and FACS-T showed the highest percentages of early and late apoptosis on HeLa cells. A cell cycle analysis demonstrated increased G2/M arrest on HeLa cells with docetaxel and paclitaxel-encapsulated FACS-R and FACS-T. The FACS-T induced more G2/M arrest on HeLa cells than the FACS-R. To assess applications in near-infrared photothermal therapy (PTT), the cell viability on HeLa cells with the anticancer agent-encapsulated FACS-R and FACS-T was assessed in the presence or absence of 808 nm laser irradiation. The results showed that 808 nm laser irradiation significantly decreased cell viability.

Conclusion

Collectively, the triangular silver nanoplates were more effective than the gold nanorods for PTT. We believe that as-prepared nanoparticles have remarkable features and will become promising future nanomedicine.

Effect of Methyl Jasmonate Treatment on Primary and Secondary Metabolites and Antioxidant Capacity of the Substrate and Hydroponically Grown Chinese Chives

Hydroponic culture has become a commercial planting model for leafy vegetables, herbs, and other plants with medicinal value. Methyl jasmonate (MeJA) is involved in primary and secondary plant metabolism; moreover, it regulates plant bioactive compounds and enhances the nutritional and medicinal value of plants. We performed targeted metabolomic analysis of the primary and secondary metabolites in substrate-grown and hydroponic Chinese chive leaves sprayed with MeJA (0, 300, 500, and 800 μM). Using ultra-performance liquid chromatography (UPLC), UPLC tandem mass spectrometry, and chemometric tools, and analyzed the antioxidant activity of these plants. We identified the biomarkers of amino acids (serine, proline, lysine, and arginine) and phenolic compounds (4-coumaric acid and protocatechuic acid) using chemometric tools to distinguish between substrate-grown and hydroponic Chinese chives treated with MeJA. MeJA (500 μM) treatment significantly increased the total sugar and amino acid (essential and non-essential amino acids and sulfur-containing amino acids) contents of hydroponically grown Chinese chives. However, the changes in total sugar and amino acid contents in Chinese chive grown in substrates showed the opposite trend. The organic acid content of hydroponically grown Chinese chives treated with MeJA decreased significantly, whereas that of substrate-grown plants treated with 300 μM MeJA increased significantly. Further, MeJA treatment significantly increased the phenolic content of substrate-grown Chinese chives. Treatment with 800 μM MeJA significantly increased the carotenoid content of substrate-grown Chinese chives and the phenolic content of hydroponic Chinese chives. In addition, the 500 μM MeJA treatment significantly increased the antioxidant activity of Chinese chives in both substrate-grown and hydroponic cultures, and promoted the accumulation of nutrients and bioactive substances. This treatment also improved the flavor quality of these plants and their nutritional and medicinal value. Thus, the results suggested that MeJA-treated plants could be used as value-added horticultural products.

Chemical Composition and Agronomic Traits of Allium sativum and Allium ampeloprasum Leaves and Bulbs and Their Action against Listeria monocytogenes and Other Food Pathogens

In this work, we aimed to study the chemical composition of the essential oils from bulbs and leaves of two cultivars of Allium sativum L. and two of A. ampeloprasum L. var. holmense. Moreover, we investigated their activity against four common bacterial strains responsible for food contamination (Listeria monocytogenes, Escherichia coli, Acinetobacter baumannii, and Staphylococcus aureus) by formation of biofilms. The susceptibility of bacterial biofilms was evaluated by crystal violet assay, whereas the metabolic changes occurring in the bacterial cells were ascertained through the MTT test. The essential oils were characterized by the presence of most characteristic components, although with different composition between the species and the cultivars. The essential oils inhibited the capacity of the pathogenic bacteria to form biofilms (up to 79.85 against L. monocytogenes) and/or acted on their cell metabolism (with inhibition of 68.57% and 68.89% against L. monocytogenes and S. aureus, respectively). The capacity of the essential oils to act against these foodborne bacteria could suggests further ideas for industrial applications and confirms the versatility of these essential oils as food preservatives.

Effect of blend oil on the volatile aroma profile and storage quality of garlic paste

The aim of this study was to evaluate the effect of edible oil on the volatile aroma profile and storage quality of garlic paste, and to explore the underlying mechanisms. The administration of blend oil at 40 °C in a garlic to oil ratio of 1.8 had a higher overall acceptance by affective sensory test. Compared with the original garlic paste, the sensory aroma profile of the oil-immersed garlic paste was characterized by suppressed pungency, garlic scent and garlic odor, and enhanced oil scent. SPME-GC-MS and HS-GC-IMS showed that the application of blend oil caused great changes in the level of some compounds, which could explain its role in the oil-immersed garlic paste. Furthermore, the blend oil also reduced the growth rate of the total number of colonies and browning intensity, and inhibited the loss of allicin. Therefore, the application of blend oil in garlic paste improved the sensory aroma and delayed the deterioration of the product quality.

Dietary Organosulfur-Containing Compounds and Their Health-Promotion Mechanisms

Dietary organosulfur-containing compounds (DOSCs) in fruits, vegetables, and edible mushrooms may hold the key to the health-promotion benefits of these foods. Yet their action mechanisms are not clear, partially due to their high reactivity, which leads to the formation of complex compounds during postharvest processing. Among postharvest processing methods, thermal treatment is the most common way to process these edible plants rich in DOSCs, which undergo complex degradation pathways with the generation of numerous derivatives over a short time. At low temperatures, DOSCs are biotransformed slowly during fermentation to different metabolites (e.g., thiols, sulfides, peptides), whose distinctive biological activity remains largely unexplored. In this review, we discuss the bioavailability of DOSCs in human digestion before illustrating their potential mechanisms for health promotion related to cardiovascular health, cancer chemoprevention, and anti-inflammatory and antimicrobial activities. In particular, it is interesting that different DOSCs react with glutathione or cysteine, leading to the slow release of hydrogen sulfide (H2S), which has broad bioactivity in chronic disease prevention. In addition, DOSCs may interact with protein thiol groups of different protein targets of importance related to inflammation and phase II enzyme upregulation, among other action pathways critical for health promotion.

Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Antitumor Effects of Natural Compounds Derived from Allium sativum on Neuroblastoma: An Overview

Garlic (Allium sativum) has been used in alternative medicine to treat several diseases, such as cardiovascular and neurodegenerative diseases, cancer, and hepatic diseases. Several publications have highlighted other features of garlic, including its antibacterial, antioxidative, antihypertensive, and antithrombotic properties. The properties of garlic result from the combination of natural compounds that act synergistically and cause different effects. Some garlic-derived compounds have been studied for the treatment of several types of cancer; however, reports on the effects of garlic on neuroblastoma are scarce. Neuroblastoma is a prevalent childhood tumor for which the search for therapeutic alternatives to improve treatment without affecting the patients’ quality of life continues. Garlic-derived compounds hold potential for the treatment of this type of cancer. A review of articles published to date on some garlic compounds and their effect on neuroblastoma was undertaken to comprehend the possible therapeutic role of these compounds. This review aimed to analyze the impact of some garlic compounds on cells derived from neuroblastoma.

Garlic: An Alternative Treatment for Group B Streptococcus

Prenatal screening in pregnant women between 35 and 37 weeks of gestation and intrapartum antibiotic prophylaxis has successfully reduced the incidence of neonatal morbidity and mortality related to Streptococcus agalactiae. However, the contamination rates of newborns are still considerable. In traditional and folk medicines, it has been observed that garlic has been effective in treating S. agalactiae infection. The aim of this study was to isolate and identify the active compounds from garlic that have antimicrobial activity against S. agalactiae. In order to do this, SP80 (Sep-Pak 80%) obtained from crude garlic extract (CGE) was fractionated by reverse-phase ultrafast liquid chromatography with UV (RP-UFLC-UV) using a Shim-pack PREP-ODS column. All fractions obtained were tested using a microbial growth inhibition test against the S. agalactiae strain (ATCC 12386). Five clinical isolates were used to confirm the action of the fractions with antimicrobial activity, and the bacterial growth curve was determined. Identification of the antimicrobial compounds was carried out through liquid chromatography coupled with mass spectrometry (LC/MS) and nuclear magnetic resonance (NMR). The active compounds found to exhibit antimicrobial activity were Ƴ-glutamyl-S-allyl-cysteine (fraction 18), Ƴ-glutamyl-phenylalanine (fraction 20), and the two stereoisomers (E and Z) of ajoene (fraction 42). The MICs of these fractions were 5.41 mg/ml, 4.60 mg/ml, and 0.16 mg/ml, respectively, and they inhibited the growth of the clinical isolates tested. Antimicrobial compounds from garlic may be a promising source in the search for new drugs against S. agalactiae. IMPORTANCE Invasive disease due to group B streptococcal (GBS) infection results in a wide spectrum of clinical disease in neonates. Maternal colonization by GBS is the primary risk factor for disease. The strategy recommended by the Centers for Disease Control to reduce neonatal GBS infection is the culture-based screening of all pregnant women at 35 to 37 weeks of gestation and intrapartum antibiotic prophylaxis (IAP). However, indiscriminate use of antibiotics favors the selection and spread of resistant bacteria. The global scenario of antibacterial resistance has been of great concern for public health, and natural products can be a source of new substances to help us grapple with this problem.

Does Curing Moisture Content Affect Black Garlic Physiochemical Quality?

This research examined the changes of black garlic (BG) quality attributes when raw materials of different initial moisture contents (iMC) were used. Fresh garlic bulbs (cv. Thai) were shade-dried for eight weeks at a controlled condition at 29 °C and relative humidity (RH) of 55% to the desired iMC (ranging from ca. 50–70%). BG processing was at 75 °C, RH = 80% for ten days. After processing, physiological characteristics and chemical properties of garlic were determined. Results illustrated that fresh garlic with higher moisture content (ca. 70%) resulted in BG of a dark brown colour, sloppy texture, and lesser acidity (pH = 4.44), while samples with lower iMCs (<50%) gave products that were completely black, elastic in texture, and with higher acidity (pH = 3.79). The analysed bioactive compounds, as well as their antioxidative potentials, suggested that the longer the curing time, the higher the functional properties of the finished products, possessing a total phenolic, total flavonoid content, and antioxidant activity of 15.54 mg/kg dry matter sample, 1.53 mg/kg dry matter sample, and 95.39%, respectively. Principle component analysis (PCA) of active metabolites confirmed that sulfur, S-allyl-L-cysteine, and flavonoid were among the main phytochemicals found in the BG. In summary, higher quality BG can be achieved by using raw materials of lower iMC.

Effects of garlic intake on cancer: a systematic review of randomized clinical trials and cohort studies

BACKGROUND/OBJECTIVES

Due to the rapid increase of global cancer incidence and mortality and a high level of interest in cancer prevention, a systematic review of garlic intake and cancer risk is needed.

SUBJECTS/METHODS

We implemented a systematic review to examine the effects of varying levels of garlic intake on cancer. We conducted comprehensive literature searches in three electronic databases (MEDLINE, Embase, and Web of Science) for studies published between database inception and July or September of 2018. Two investigators independently screened abstracts and full-texts, extracted data, and assessed risk of bias (RoB). A total of one medium-quality randomized controlled trial (RCT) and 13 cohort studies graded as high RoB were included.

RESULTS

The 1-year follow-up results from a RCT showed that a significant decrease in the number and size of colorectal adenomas among participants with colorectal adenomas who received high-dose aged garlic extract (AGE) compared with those who received low-dose AGE (P < 0.05). The results of prospective observational studies provided inconsistent associations of colorectal cancer risk with garlic supplements and garlic intake as food.

CONCLUSIONS

In summary, the AGE was effective in reducing the number and magnitude of colorectal adenomas in one RCT, but there were inconsistent associations between garlic intake and colorectal cancer in cohort studies. Therefore, we could not draw a firm conclusion regarding the effects of garlic on cancer, because the current strength of evidence is inadequate due to a lack of number of high-quality RCTs.

Association between dietary onion intake and subclinical hypothyroidism in adults: a population-based study from an iodine-replete area

PURPOSE

The protective effect of onion against thyroid hypofunction has been reported in animal studies. However, in humans, the association between onion consumption and subclinical hypothyroidism (SCH) are unclear. The study sought to explore the association between habitual onion intake and SCH among adult population from an iodine-replete area.

METHODS

A cross-sectional study (6515 men and 5290 women) was performed in Tianjin, China. Frequency of onion consumption was assessed using a valid self-administered food frequency questionnaire. Serum free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) were determined by chemiluminescence immunoassay. SCH was diagnosed with TSH > 4.78 mIU/L. Multiple logistic regression was used to evaluate the association of onion intake with SCH.

RESULTS

The prevalence of SCH was 2.56% in men and 7.18% in women, respectively. In women, the fully adjusted odds ratios [95% confidence interval (CI)] of having SCH across increasing frequency of onion intake were 1.00 (reference) for <1 time/week, 0.99 (0.73, 1.34) for 1-3 times/week, 0.74 (0.53, 1.03) for 4-6 times/week, and 0.67 (0.47, 0.97) for ≥7 times/week (P for trend <0.01). However, we observed no significant association between onion intake and SCH in men. Stratified analyses suggested a potential effect modification by age: the odds ratios (95% CI) across extreme quartiles was 0.37 (0.17, 0.80) in <40 women and 1.11 (0.51, 2.47) in >60 women.

CONCLUSIONS

Frequent consumption of onion is inversely associated with SCH in adult women from an iodine-replete area. Further studies are needed to explore the casual relationship. TRIAL REGISTRATION WEBSITE: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000031137.

Allicin protects against renal ischemia-reperfusion injury by attenuating oxidative stress and apoptosis

Background

Studies have demonstrated that allicin may play critical roles in the procession of ischemia–reperfusion(I/R) injury. The purpose of this study was to investigate the protective effects of allicin on renal I/R injury by attenuating oxidative stress and apoptosis.

Methods

To establish a model of renal I/R, the right kidney underwent 12 h reperfusion after 45 min ischemia, allicin was administered intraperitoneally at concentrations of 40, 50 or 60 mg/kg. NRK-52E cells were treated with allicin at concentrations of 1, 3 or 5 μM in 24 h hypoxia/ 6 h reoxygenation(H/R) treatments. Indicators of HE, oxidative stress, apoptosis were measured to evaluate the effect of aliicin on renal I/R injury.

Results

Allicin protected renal I/R injury by ameliorating histological injury and decreasing the oxidative stress in renal tissues. Meanwhile, allicin significantly downregulated the expression of Bax and caspase-3, upregulated the expression of Bcl-2 in I/R renal tissues and H/R treated NRK-52E cells.

Conclusions

Allicin may exert anti-apoptotic and antioxidative effects to promote renal function recovery in I/R renal tissues and H/R treated NRK-52E cells. Taken together, allicin may be a potential novel therapy option for future renal injury protection.

Development of Optimized Ultrasound-Assisted Extraction Methods for the Recovery of Total Phenolic Compounds and Anthocyanins from Onion Bulbs

Allium cepa L. is one of the most abundant vegetable crops worldwide. In addition to its versatile culinary uses, onion also exhibits quite interesting medicinal uses. Bulbs have a high content of bioactive compounds that are beneficial for human health. This study intends to develop and optimize two appropriate ultrasound-assisted methods for the extraction of the phenolic compounds and anthocyanins present in red onion. A response surface methodology was employed and, specifically, a Box–Behnken design, for the optimization of the methods. The optimal conditions for the extraction of the phenolic compounds were the follows: 53% MeOH as solvent, pH 2.6, 60 °C temperature, 30.1% amplitude, 0.43 s cycle, and 0.2:11 g sample/mL solvent ratio. On the other hand, the optimal conditions for the anthocyanins were as follows: 57% MeOH as solvent, pH 2, 60 °C temperature, 90% amplitude, 0.64 s cycle, and 0.2:15 g sample/mL solvent ratio. Both methods presented high repeatability and intermediate precision, as well as short extraction times with good recovery yields. These results illustrate that the use of ultrasound-assisted extraction, when properly optimized, is suitable for the extraction and quantification of the compounds of interest to determine and improve the quality of the raw material and its subproducts for consumers.

Diallyl sulfide protects against dilated cardiomyopathy via inhibition of oxidative stress and apoptosis in mice

Cytochrome P450 family 2 subfamily E member 1 (CYP2E1) is a member of the cytochrome P450 enzyme family and catalyzes the metabolism of various substrates. CYP2E1 is upregulated in multiple heart diseases and causes damage mainly via the production of reactive oxygen species (ROS). In mice, increased CYP2E1 expression induces cardiac myocyte apoptosis, and knockdown of endogenous CYP2E1 can attenuate the pathological development of dilated cardiomyopathy (DCM). Nevertheless, targeted inhibition of CYP2E1 via the administration of drugs for the treatment of DCM remains elusive. Therefore, the present study aimed to investigate whether diallyl sulfide (DAS), a competitive inhibitor of CYP2E1, can be used to inhibit the development of the pathological process of DCM and identify its possible mechanism. Here, cTnT^R141W transgenic mice, which developed typical DCM phenotypes, were used. Following treatment with DAS for 6 weeks, echocardiography, histological analysis and molecular marker detection were conducted to investigate the DAS-induced improvement on myocardial function and morphology. Biochemical analysis, western blotting and TUNEL assays were used to detected ROS production and myocyte apoptosis. It was found that DAS improved the typical DCM phenotypes, including chamber dilation, wall thinning, fibrosis, poor myofibril organization and decreased ventricular blood ejection, as determined using echocardiographic and histopathological analyses. Furthermore, the regulatory mechanisms, including inhibition both of the oxidative stress levels and the mitochondria-dependent apoptosis pathways, were involved in the effects of DAS. In particular, DAS showed advantages in terms of improved chamber dilation and dysfunction in model mice, and the improvement occurred in the early stage of the treatment compared with enalaprilat, an angiotensin-converting enzyme inhibitor that has been widely used in the clinical treatment of DCM and HF. The current results demonstrated that DAS could protect against DCM via inhibition of oxidative stress and apoptosis. These findings also suggest that inhibition of CYP2E1 may be a valuable therapeutic strategy to control the development of heart diseases, especially those associated with CYP2E1 upregulation. Moreover, the development of DAS analogues with lower cytotoxicity and metabolic rate for CYP2E1 may be beneficial.

The Potential Benefits of Using Garlic Oil and Its Active Constituent, Dially Disulphide, in Combination With Carvedilol in Ameliorating Isoprenaline-Induced Cardiac Damage in Rats

Garlic oil and its primary component, diallyl disulphide (DADS), were tested in rats with isoprenaline (ISO) induced myocardial infarction for cardioprotective benefits when combined with carvedilol. Garlic oil (GO) was administered to rats (Sprague-dawley strain) at two doses of 50 and 100 mg/kg body weight, whereas DADS was given in two doses of 4.47 and 8.94 mg/kg, respectively. The animals were given oral doses of garlic oil and DADS on alternate days for 3 weeks, either alone or in combination with carvedilol (2 mg/kg). Cardiac injury was done by administering two doses of isoprenaline (150 mg/kg, sc) to all treated groups except the first, which served as a control. Biomarkers of cardiac injury and histological investigations were studied for their potential in reducing ISO-induced myocardial damage. Animals pretreated with GO, DADS, and carvedilol had significantly (p < 0.01) lowered heart weight and heart to body weight ratio. In rats treated with carvedilol plus high dosages of garlic oil (100 mg/kg, p.o) and DADS (8.94 mg/kg, p.o) compared to the ISO control and carvedilol group, the activities of SOD and Catalase were enhanced in cardiac tissue homogenate. When compared to ISO control and carvedilol group, the activities of LDH and CK-MB were elevated in heart tissue homogenate with a simultaneous reduction in their serum levels in animals treated with a combination of carvedilol with high doses of garlic oil (100 mg/kg, p.o) and DADS (8.94 mg/kg, p.o). Overall, combining garlic oil or DADS with carvedilol improved the cardioprotective effect of carvedilol and protected rats from ISO-induced myocardial infarction. However, more research is needed to establish the mechanism of garlic oil and DADS interaction with carvedilol.

In vitro and in vivo antihypertensive and antioxidant activities of fermented roots of Allium hookeri

Objective

To evaluate antihypertensive and antioxidant activities of Allium hookeri root (AHR) fermented with Lactobacillus plantarum, Leuconostoc mesenteroides, and Weissella cibaria.

Methods

The novel fermented AHR products using L. plantarum, L. mesenteroides, and W. cibaria were developed and ACE inhibitory activity, DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, total phenolic content, and total thiosulfinate content were determined. The antihypertensive and antioxidant effects of fermented AHR were further investigated in spontaneously hypertensive rats (SHRs).

Results

Administration of fermented AHR to SHRs had an attenuating effect on both diastolic and systolic blood pressure. The SHRs treated with fermented AHR showed lower plasma ACE activity and higher plasma NO levels. Furthermore, fermented AHR administration led to parallel improvements in plasma oxidative stress biomarkers in SHRs.

Conclusion

Our results highlight the potential usefulness of fermented AHR for the prevention of hypertension.

Current Advances and Outlook in Gastric Cancer Chemoresistance: A Review

BACKGROUND

Surgical resection of the lesion is the standard primary treatment of gastric cancer. Unfortunately, most patients are already in the advanced stage of the disease when they are diagnosed with gastric cancer. Alternative therapies, such as radiation therapy and chemotherapy, can achieve only very limited benefits. The emergence of cancer drug resistance has always been the major obstacle to the cure of tumors. The main goal of modern cancer pharmacology is to determine the underlying mechanism of anticancer drugs.

OBJECTIVE

Here, we mainly review the latest research results related to the mechanism of chemotherapy resistance in gastric cancer, the application of natural products in overcoming the chemotherapy resistance of gastric cancer, and the new strategies currently being developed to treat tumors based on immunotherapy and gene therapy.

CONCLUSION

The emergence of cancer drug resistance is the main obstacle in achieving alleviation and final cure for gastric cancer. Mixed therapies are considered to be a possible way to overcome chemoresistance. Natural products are the main resource for discovering new drugs specific for treating chemoresistance, and further research is needed to clarify the mechanism of natural product activity in patients. .

Ethanol-based garlic extract prevents malignant evolution of non-invasive breast tumor cells induced by moderate hypoxia

BACKGROUND

In breast cancer, low oxygen availability is associated with a more aggressive phenotype and with malignant evolution of non-invasive cells. Natural compounds have long attracted attention in cancer treatment, and in recent years garlic (Allium sativum) organosulfur derivatives have been shown to negatively affect growth and invasion of tumor cells.

METHODS

Homemade ethanol-based garlic extract (GE) was administered to MCF7 and MCF10DCIS breast tumor cell lines grown under moderate hypoxia. Cell cycle, epithelial-to-mesenchymal transition and cancer stem cell markers were evaluated.

RESULTS

We revealed that, in the non-invasive MCF10DCIS cells but not in the post-EMT MCF7 cells, low oxygen availability induced the decrease of E-cadherin and the increase of vimentin and motility, that were prevented by GE administration. In both cell lines, treatment with GE counteracted the up-modulation of CD133 positive cells induced by hypoxia.

CONCLUSIONS

Overall, our data firstly revealed anti-cancer properties of garlic in non-invasive breast cancer cells. In particular, they demonstrated a protective role of this natural product against the hypoxia-induced increase of molecules that play crucial roles in tumor evolution, suggesting that garlic derivatives can be considered in new approaches for preventing progression of breast tumors from non-invasive to infiltrating lesions.

Comparison of the effects of LED light quality combination on growth and nutrient accumulation in green onion (Allium fistulosum L.)

The growth and development and metabolism of plants have different physiological responses to different light qualities. To study the influence of light qualities on green onions, the impacts of LED light treatment on the growth and development as well as the nutritional components and flavor substances in green onions were studied under controlled conditions. Leaf area, plant height, dry matter accumulation, Dickson's quality index (DQI), nutritional content, and volatile compounds under different light quality treatments were determined. The results indicated that the white and blue combined light (W/B: 3/1) treatment was the most beneficial to growth and nutrient accumulation and led to higher levels of sulfur compounds in the green onions than the other treatments. This shows that it is possible to control the contents of compounds that affect consumer preferences by adjusting the lighting conditions and to thereby increase the value and quality of seasoning vegetables.

Relationship between Volatile Composition and Bioactive Potential of Vegetables and Fruits of Regular Consumption-An Integrative Approach

In recent years, there has been a growing interest in studying and exploring the potential health benefits of foods, mainly from vegetables and fruits from regular intake. The presence of secondary metabolites, namely polyphenols, carotenoids and terpenes, in certain food matrices seems to contribute to their functional properties, expressed through an increased prevention in the development of certain chronic diseases, namely coronary heart diseases, neurodegenerative diseases, cancer and diabetes. However, some foods' volatile secondary metabolites also present important bioactive properties, although this is a poorly scientifically explored field. In this context, and in order to explore the potential bioactivity of volatile metabolites in different vegetables and fruits from regular consumption, the volatile composition was established using a green extraction technique, solid phase microextraction in headspace mode (HS-SPME), combined with gas chromatography tandem mass spectrometry (GC-MS). A total of 320 volatile metabolites, comprising 51 terpenic compounds, 45 organosulfur compounds, 31 aldehydes, 37 esters, 29 ketones, 28 alcohols, 23 furanic compounds, 22 hydrocarbons, 19 benzene compounds, 13 nitrogenous compounds, 9 carboxylic acids, 7 ethers, 4 halogenated compounds and 3 naphthalene derivatives, were positively identified. Each investigated fruit and vegetable showed a specific volatile metabolomic profile. The obtained results revealed that terpenic compounds, to which are associated antimicrobial, antioxidant, and anticancer activities, are the most predominant chemical family in beetroot (61%), orange carrot (58%) and white carrot (61%), while organosulfur compounds (antiviral activity) are dominant in onion, garlic and watercress. Broccoli and spinach are essentially constituted by alcohols and aldehydes (enzyme-inhibition and antimicrobial properties), while fruits from the Solanaceae family are characterized by esters in tamarillo and aldehydes in tomato.

Diallyl trisulfide protects against concanavalin A-induced acute liver injury in mice by inhibiting inflammation, oxidative stress and apoptosis

AIMS

To investigate the protective effects and underlying mechanisms of diallyl trisulfide (DATS) against acute liver injury induced by concanavalin A (Con A).

MATERIALS AND METHODS

DATS (20, 40, 80 mg/kg) were gavaged to ICR mice 1 h before Con A (20 mg/kg) tail vein injection. The survival rate of mice, alterations of serum biochemical markers and liver histopathology were measured to evaluate the protective effects of DATS at 24 h after Con A exposure. The indexes of inflammation, oxidative stress and apoptosis were determined to explore the possible mechanisms.

KEY FINDINGS

DATS pretreatment increased survival rate of mice in a dose-dependent manner, inhibited the increase of liver-to-spleen ratio and serum liver injury markers, and attenuated liver pathological damage induced by Con A. Further study showed that DATS pretreatment inhibited the activation of Kupffer cells/macrophages, release of tumor necrosis factor-α (TNF-α) and Caspase-1-dependent inflammation induced by Con A. Moreover, DATS pretreatment alleviated the oxidative stress induced by Con A, which was evidenced by increased superoxide dismutase (SOD) and catalase (CAT) activities and decreased malondialdehyde (MDA) content in DATS and Con A co-treated mice compared with Con A alone group. Finally, DATS pretreatment reduced eosinophilic body formation, TUNEL positive staining and increased Bcl-2/Bax ratio in liver of Con A-injected mice, indicating attenuated apoptosis.

SIGNIFICANCE

Collectively, the results suggest that DATS displays potent protective effects against Con A-induced acute liver injury in mice possibly through inhibition of inflammation, oxidative stress and apoptosis.

Allicin and Digestive System Cancers: From Chemical Structure to Its Therapeutic Opportunities

Digestive system cancer tumors are one of the major causes of cancer-related fatalities; the vast majority of them are colorectal or gastric malignancies. Epidemiological evidence confirmed that allium-containing food, such as garlic, reduces the risk of developing malignancies. Among all compounds in garlic, allicin has been most researched, as it contains sulfur and produces many second degradation compounds, such as sulfur dioxide, diallyl sulfide (DAS), diallyl trisulfide (DATS), and diallyl disulfide (DADS) in the presence of enzymatic reactions in gastric juice. These substances have shown anti-inflammatory, antidiabetic, antihypertensive, antifungal, antiviral, antibacterial, and anticancer efficacy, including gastrointestinal (GI) cancers, leukemia, and skin cancers. Herein, we summarize the therapeutic potential of allicin in the treatment of GI cancers.

Phytochemical Characterization and Screening of Antioxidant, Antimicrobial and Antiproliferative Properties of Allium × cornutum Clementi and Two Varieties of Allium cepa L. Peel Extracts

Onions are one of the most widely grown vegetable crops. As production increases, so does the generation of waste from various parts of the onion, raising the need for efficient ecological disposal and use of such waste products. However, onion waste products are a rich source of antioxidants with a range of biological properties, therefore, they could potentially be used in food and pharmaceutical industries. In the present study, we identified the main flavonols and anthocyanins in peel extracts of Allium × cornutum Clement ex Visiani, 1842, and two varieties of Allium cepa L. and tested their antioxidant, antimicrobial and antiproliferative properties. Quercetin 3,4′-diglucolside, quercetin 4′-monoglucoside and quercetin are the most abundant flavonols in all onion extracts detected by high-performance liquid chromatography (HPLC) method. The composition of anthocyanins varied in all extracts. 2,2′-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays showed that the triploid onion A. × cornutum had the highest antioxidant power. Evaluation of antimicrobial activity by broth microdilution assay also showed that A. × cornutum had higher antimicrobial activity compared to the red and yellow onion varieties. Comparable antiproliferative activity was confirmed for all onion extracts tested on three cancer cell lines: Hela (cervical cancer cell line), HCT116 (human colon cancer cell line) and U2OS (human osteosarcoma cell line). The most abundant onion flavonols (quercetin 3,4′-diglucoside and quercetin 4′-monoglucoside) showed weaker antimicrobial as well as antiproliferative properties compared to the extracts, leading to the conclusion that other phytochemicals besides flavonols contribute to the biological activity of onion peel extracts. The results demonstrate the antioxidant and antimicrobial properties of onion peels, which have promising potential as cancer cell proliferation inhibitors.

Rojo Duro Red Onion Extract Loaded Spray Thermogel as a Sustainable Platform for the Treatment of Oral Mucosa Lesions

The urgent need for new green and sustainable models is ground for the current demand of innovative renewable resource based pharmaceutical products. We propose a Rojo Duro skin onion extract loaded poloxamer/chitosan spray mucoadhesive thermogel aimed at solving current limitations in oral mucosits treatment. Being among the main side effects of radio- and chemotherapy, effective treatment of buccal lesions still represents an unmet medical need. The obtained thermogel combined optimal gelling capacity, release behavior, sprayability, mucoadhesion properties, while maintaining the extract antioxidant and antimicrobial properties. The product preserved all properties when stored for 1 month as a freeze-dried powder at 4 °C. This potential new product is highly translational, as it combines a recognized safety to administration/application advantages, as well as simplicity and sustainability.

Restorative effects of red onion (Allium cepa L.) juice on erectile function after-treatment with 5α-reductase inhibitor in rats

Benign prostatic hyperplasia (BPH) is one of the most prevalent conditions among aged men. The use of 5α-reductase inhibitors (5-ARIs) to treat BPH was linked to erectile dysfunction (ED). Many medicinal plants and secondary metabolites are used in the management of ED. Onion (Allium cepa L.) is an economically affordable vegetable with vital phytochemicals and biological functions. The study aimed to identify the beneficial effects of onion juice on dutasteride (a 5-ARI)-induced ED. Rats were divided into two groups (n = 5 per group): control and dutasteride-treated rats (0.5 mg/kg/day). Dutasteride was administered in drinking water for 12 weeks. Experiments were performed at the end of the 12th week. In vivo erectile responses were measured before and after intracavernosal injection of onion. Relaxant responses to onion juice were examined in the corpus cavernosum (CC). Acetylcholine (ACh)-, electrical field stimulation (EFS)-, sodium nitroprusside (SNP)-induced relaxation responses in CC tissues were evaluated in the absence and presence of onion juice. Total intracavernosal pressure (ICP) and ICP/ mean arterial pressure were significantly reduced in dutasteride-treated rats (1881.14 ± 249.72 mmHg, P < 0.001;0.26 ± 0.03, P < 0.01) as compared to control rats (4542.60 ± 429.19 mmHg, 0.51 ± 0.05), which was normalized after the intracavernous administration of onion (3288.60 ± 185.45 mmHg, 0.58 ± 0.04). Onion markedly induced relaxant responses in control (72.5 ± 4.7) and dutasteride-treated (66.5 ± 2.7) groups after precontraction with phenylephrine. Relaxation responses to onion were partially inhibited after precontraction with KCl (32.5 ± 3.1, P < 0.001). The relaxant responses to ACh (14.9 ± 4.2, P < 0.01) were diminished in dutasteride-treated CC) compared to control CC (59.8 ± 3.4), which was enhanced after the incubation with onion (36.6 ± 4.8). There were no differences in relaxation response to SNP among all groups. However, relaxation response to SNP was reduced in dutasteride-treated CC at 1 μM (P < 0.05) and 10 μM dosages (P < 0.001), which was partially increased after the incubation with onion at 10 μM dosage (P < 0.01). The presence of onion did not change the reduction in EFS-caused relaxation in the dutasteride-treated group. The current data suggest that red onion juice has a restorative effect on erectile function and endothelium-dependent relaxation response following the treatment of dutasteride.

The Potential Application of Allium Extracts in the Treatment of Gastrointestinal Cancers

Herbal medicine is currently widely practiced, since natural resources are reported to alleviate side effects during oncological treatment while modifying cancer cell responses at the same time. Allium vegetables and their constituents have recently been extensively investigated due to the numerous possible beneficial properties, establishing them as an additional treatment modality in different cancers. According to the epidemiological evidence, as well as many in vivo and in vitro studies, the abovementioned substances seem to be effective in the prevention and inhibition of the progression of carcinogenesis. Due to high concentrations of organosulfur compounds, which exhibit anticarcinogenic, antimicrobial, as well as anti-inflammatory properties, Allium constituents are believed to constitute a promising prevention and supportive therapy for oncological patients. Besides, it was demonstrated that a combination of Allium extracts with chemotherapy provided satisfactory clinical outcomes while at the same time being cost-effective. The aim of this review was to present and discuss currently investigated Allium extracts and their effects on several gastrointestinal cancers including gastric, colon, liver, esophageal, and pancreatic cancer.

Diallyl disulphide-loaded spherical gold nanoparticles and acorn-like silver nanoparticles synthesised using onion extract: catalytic activity and cytotoxicity

Onion (Allium cepa) extract was used for the green synthesis of gold and silver nanoparticles. Each colloidal solution exhibited surface plasmon resonance, with a peak at 532 nm for gold nanoparticles and 391 nm for silver nanoparticles. Microscopic results confirmed the presence of spherical shapes. The X-ray diffraction pattern demonstrated a face-centered cubic structure. Both nanoparticles had negative zeta potentials and retained colloidal stability in cell culture medium. Catalytic applications were evaluated for 4-nitrophenol reduction and methyl orange degradation reactions by monitoring with UV-visible spectrophotometry. Furthermore, the nanoparticles demonstrated no significant cytotoxicity against human pancreas ductal adenocarcinoma cells (PANC-1) and human colorectal adenocarcinoma cells (HT-29). PEGylation and diallyl disulphide loading of the gold and silver nanoparticles meaningfully reduced the cell viability of both cell lines. Furthermore, diallyl disulphide loading resulted in more cytotoxicity against PANC-1 cells than against HT-29 cells. Additionally, the gold nanoparticles were more cytotoxic than the silver nanoparticles upon diallyl disulphide loading. Interestingly, after PEGylation and diallyl disulphide loading, the silver nanoparticles exhibited acorn-like shapes, while the gold nanoparticles retained spherical shapes. This result suggested that nanoparticles green-synthesised by onion extract have possibilities as nanocatalysts and drug delivery nanocarriers for catalytic and nanomedicine applications.

Plant Prebiotics and Their Role in the Amelioration of Diseases

Prebiotics are either natural or synthetic non-digestible (non-)carbohydrate substances that boost the proliferation of gut microbes. Undigested fructooligosaccharides in the large intestine are utilised by the beneficial microorganisms for the synthesis of short-chain fatty acids for their own growth. Although various food products are now recognized as having prebiotic properties, several others, such as almonds, artichoke, barley, chia seeds, chicory, dandelion greens, flaxseeds, garlic, and oats, are being explored and used as functional foods. Considering the benefits of these prebiotics in mineral absorption, metabolite production, gut microbiota modulation, and in various diseases such as diabetes, allergy, metabolic disorders, and necrotising enterocolitis, increasing attention has been focused on their applications in both food and pharmaceutical industries, although some of these food products are actually used as food supplements. This review aims to highlight the potential and need of these prebiotics in the diet and also discusses data related to the distinct types, sources, modes of action, and health benefits.

Functional relationship of vegetable colors and bioactive compounds: Implications in human health

Vegetables are essential protective diet ingredients that supply ample amounts of minerals, vitamins, carbohydrates, proteins, dietary fiber, and various nutraceutical compounds for protection against various disease conditions. Color is the most important quality parameter for the farmers to access the harvest maturity while for the consumer's reliable indices to define acceptability or rejection. The colored vegetables contain functional compounds like chlorophylls, carotenoids, betalains, anthocyanins, etc. well recognized for their antioxidant, antimicrobial, hypolipidemic, neuroprotective, antiaging, diuretic, and antidiabetic properties. Recently, there has been a shift in food consumption patterns from processed to semi-processed or fresh fruits and vegetables to ensure a healthy disease-free life. This shifted the focus of agriculture scientists and food processors from food security to nutrition security. This has resulted in recent improvements to existing crops like blue tomato, orange cauliflower, colored and/or black carrots, with improved color, and thus enriched bioactive compounds. Exhaustive laboratory trials though are required to document and establish their minimum effective concentrations, bioavailability, and specific health benefits. Efforts should also be directed to breed color-rich cultivars or to improve the existing varieties through conventional and molecular breeding approaches. The present review has been devoted to a better understanding of vegetable colors with specific health benefits and to provide in-hand information about the effect of specific pigment on body organs, the effect of processing on their bioavailability, and recent improvements in colors to ensure a healthy lifestyle.

Changes in the Organosulfur and Polyphenol Compound Profiles of Black and Fresh Onion during Simulated Gastrointestinal Digestion

This study aims to determine the changes in, and bioaccessibility of, polyphenols and organosulfur compounds (OSCs) during the simulated gastrointestinal digestion of black onion, a novel product derived from fresh onion by a combination of heat and humidity treatment, and to compare it with its fresh counterpart. Fresh and black onions were subjected to in-vitro gastrointestinal digestion, and their polyphenol and OSC profiles were determined by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS). Although to a lesser extent than in the fresh onion, the phenolic compounds in the black variety remained stable during the digestion process, presenting a higher bioaccessibility index (BI) with recovery corresponding to 41.1%, compared with that of fresh onion (23.5%). As for OSCs, apart from being more stable after the digestion process, with a BI of 83%, significantly higher quantities (21 times higher) were found in black onion than in fresh onion, suggesting that the black onion production process has a positive effect on the OSC content. Gallic acid, quercetin, isorhamnetin, and ɣ-glutamyl-S-(1-propenyl)-L-cysteine sulfoxide were the most bioaccessible compounds in fresh onion, while isorhamnetin, quercetin-diglucoside, ɣ-glutamyl-S-methyl-L-cysteine sulfoxide and methionine sulfoxide were found in black onion. These results indicate that OSCs and polyphenols are more bioaccessible in black onion than in fresh onion, indicating a positive effect of the processing treatment.

S-allylcysteine induces cytotoxic effects in two human lung cancer cell lines via induction of oxidative damage, downregulation of Nrf2 and NF-κB, and apoptosis

In this study, we investigated the putative cytotoxic effect elicited by the garlic-derived compound S-allylcysteine (SAC) in two human cancer cell lines (HCC827 and NCI-H1975) in order to develop an experimental approach to the therapeutic potential of this molecule for lung cancer. Cells were incubated for 24, 48 and 72 h in the presence of SAC (10 or 20 mM), which resulted in a concentration- and time-dependent decrease in cell viability and culture confluence in both cell lines. These effects were contrasted with - and validated through - those observed in an immortalized but nontumorigenic epithelial cell line from human bronchial epithelium (BEAS-2B, negative control) and an adenocarcinoma human alveolar basal epithelial cell line (A549, positive control). SAC (20 mM at 72 h) also increased the oxidative damage to lipids, augmented apoptosis, and decreased the expression of the nuclear factor erythroid 2-related factor 2 (Nrf2) and the nuclear factor kappa B (NF-κB) proteins in HCC827 and NCI-H1975 cells. Our results establish the efficacy of SAC in reducing malignant growth and proliferation of lung tumor cells. This effect is mediated by the induction of oxidative damage associated with the downregulation of Nrf2 and NF-κB and their corresponding signaling pathways.

Herbal therapy as a promising approach for regulation on lipid profiles: A review of molecular aspects

Impaired lipid profile is defined as abnormal plasma levels of low-density lipoprotein, triglycerides, and total cholesterol. This disease state is associated with the development and progression of various disorders, such as diabetes mellitus, cardiovascular diseases, and acute myocardial infarction. Globally, all of these disorders are related to a significant rate of death. Therefore, finding a suitable approach for the prevention and treatment of lipid profile-related disorders is in the spotlight. Recently, herbal therapy has been considered a promising therapeutic approach for the treatment of hyperlipidemia or its related disorders due to its safety and efficacy. Hereby, we address the potential benefits of some of these herbal compounds on different aspects of lipid profile and its abnormalities with a special focus on their underlying mechanisms. Using herbal products, such as teas and mushrooms, or their derivatives, Rosmarinus officinalis Linn, Curcuma longa, Green tea, Lippia triphylla, Lippia citriodora, Plantago asiatica L, Vine tea, and Grifola frondosa have been proved to exert several therapeutic impacts on lipid profile and its related disorders, and we would provide a brief review on them in this literature.

Bioactive (Poly)phenols, Volatile Compounds from Vegetables, Medicinal and Aromatic Plants

Polyphenols, as well as volatile compounds responsible for aromatic features, play a critical role in the quality of vegetables and medicinal, and aromatic plants (MAPs). The research conducted in recent years has shown that these plants contain biologically active compounds, mainly polyphenols, that relate to the prevention of inflammatory processes, neurodegenerative diseases, cancers, and cardiovascular disorders as well as to antimicrobial, antioxidant, and antiparasitic properties. Throughout the years, many researchers have deeply studied polyphenols and volatile compounds in medicinal and aromatic plants, particularly those associated with consumer's choices or with their beneficial properties. In this context, the purpose of this review is to provide an overview of the presence of volatile and nonvolatile compounds in some of the most economically relevant and consumed vegetables and medicinal and aromatic plants, with an emphasis on bioactive polyphenols, polyphenols as prebiotics, and, also, the most important factors that affect the contents and profiles of the volatile and nonvolatile compounds responsible for the aromatic features of vegetables and MAPs. Additionally, the new challenges for science in terms of improving polyphenol composition and intensifying volatile compounds responsible for the positive characteristics of vegetables and medicinal and aromatic plants are reported.

Metabolic Engineering of Isoflavonoid Biosynthesis by Expressing Glycine max Isoflavone Synthase in Allium cepa L. for Genistein Production

Isoflavonoids, the diverse group of secondary metabolites derived from the phenylpropanoid pathway, are distributed predominantly in leguminous plants and play a vital role in promoting human health. Genetic engineering of the metabolite synthesis pathway has turned out to be an attractive approach for the production of various secondary metabolites. In our study, we attempted to produce the isoflavone genistein, a well-known health-promoting metabolite, in Allium cepa L. (onion) by introducing Glycine max Isoflavone synthase (GmIFS). The GmIFS gene was cloned into the pEarleyGate 102 HA vector and transformed into onion by Agrobacterium-mediated and biolistic methods. The presence of GmIFS in transgenic onion was confirmed by PCR, dot blot, and Southern hybridization. Analysis of the transgenic onion calli lines demonstrated that the expression of the GmIFS gene led to the production of isoflavone genistein in in vitro tissues. The biolistic stable transformed calli with transformation efficiency of 73% (62.65 nM/g FW) accumulated more genistein than the Agrobacterium stable transformed calli with transformation efficiency of 56% (42.5 nM/g FW). Overall, heterologous gene expression of GmIFS was demonstrated by modifying the secondary metabolite pathway in onion tissues for the production of isoflavone genistein that can boost up human health with its health-promoting properties.

Diallyl Sulfide-Mediated Modulation of the Fatty Acid Synthase (FASN) Leads to Cancer Cell Death in BaP-Induced Lung Carcinogenesis in Swiss Mice

Purpose

Diallyl sulfide (DAS), one of the organo-sulfur secondary metabolites in garlic, has been shown to inhibit the proliferation of cancer cells. The present study aimed to evaluate the mechanism of DAS in the prevention of benzo[a]pyrene (BaP)-induced lung cancer in a murine model.

Materials and Methods

The mice were exposed to 50 mg/kg of BaP twice a week for 4 weeks in order to induce lung carcinoma. Pretreatment of mice with DAS (100 mg/kg) was started 2 weeks before BaP exposure and further continued for 21 weeks. The effect of DAS and BaP was evaluated by studying various parameters in the serum and tissues of the treated or untreated BaP-exposed mice.

Results

The histopathological findings demonstrated that DAS prevented the progression of malignant lung cancer and metastasis in the liver. A significant drop was observed in BaP-induced tumor marker enzymes (ADA, AHH, γ-GT, LDH) in the serum of the mice treated with DAS. Moreover, DAS treatment resulted in the recovery of antioxidant enzymes, SOD and CAT, in BaP-exposed mice. The induction of apoptosis and the destruction of cellular ROS were detected in cancer cells from the mice pre-treated with DAS. The immunohistochemical analysis revealed the up-regulation of fatty acid synthase (FASN) in the lungs and liver tissues of BaP-exposed mice and the treatment with DAS inhibited FASN expression.

Conclusion

The findings of the present study indicated that DAS-induced apoptosis is strongly associated with the downregulation of FASN in tumor tissues. To the best of our knowledge, this is the first study that describes the role of FASN in BaP-induced lung carcinogenesis.

Anticancer potential of garlic and its bioactive constituents: A systematic and comprehensive review

Vegetables of the Allium genus, such as garlic (Allium sativum L.), onions, shallots, leaks, and chives, have been used for many years for food consumption and for medicinal purposes. Historical medical texts have indicated the therapeutic applications of garlic as an antitumor, laxative, diuretic, antibacterial and antifungal agent. Specifically, garlic's antitumor abilities have been traced back 3500 years as a chemotherapeutic agent used in Egypt. Other beneficial effects of garlic consumption include lowering blood pressure, blood cholesterol, sugar and lipids. The processing and aging of garlic result in the production of non-toxic organosulfur by-products. These sulfur-containing compounds, such as allicin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, alliin, S-allylcysteine, and S-allylmercaptocysteine, impact various stages of carcinogenesis. The anticancer mechanisms of action of these garlic-derived phytochemicals include altering mitochondrial permeability, inhibiting angiogenesis, enhancing antioxidative and proapoptotic properties, and regulating cell proliferation. All these effects of garlic's sulfur-compounds have been demonstrated in various human cancers. The intent of this literature research is to explore the potential of garlic-derived products and bioactive organosulfur compounds as cancer chemopreventive and chemotherapeutic agents. This investigation employs criteria for systematic review and critically analyzes published in vitro, in vivo and clinical studies. Concerns and limitations that have arisen in past studies regarding standards of measurement, bioavailability, and method of delivery are addressed. Overall, it is hoped that through this systematic and comprehensive review, future researchers can be acquainted with the updated data assembled on anticancer properties of garlic and its phytoconstituents.

Protective effects of diallyl trisulfide (DATS) against doxorubicin-induced inflammation and oxidative stress in the brain of rats

Doxorubicin (DOX) is a widely used antitumor drug that causes severe neurotoxicity in patients. Diallyl trisulfide (DATS) is an organosulfur compound with established potent antioxidant and anti-inflammatory properties. Herein, we investigated the neuroprotective efficacy of DATS in preventing DOX-induced neurotoxicity in a rat model. Specifically, DATS (40 mg/kg) was administered to rats 24 h after DOX treatment, once a week for 8 weeks. Our results showed that DATS treatment led to a decrease in plasma levels of tumor necrosis factor-alpha (TNF-α) induced by DOX. DATS restored cerebral cortex and hippocampus histopathological architecture and neuronal loss. Immunohistochemical staining indicated that DATS decreased the expression of glial fibrillar acidic protein (GFAP) in DOX treated rats. Components of stress-related inflammatory proteins (TNF-α, phospho nuclear factor kappa B (NF-κB), inducible nitricoxide synthase (iNOS) and cyclooxygenase-2 (COX-2)) were all significantly increased in the DOX group, in comparison with the control group, whereas they were decreased after DATS treatment. In addition, the mRNA of antioxidant enzymes (superoxide dismutase 2 (SOD2), catalase, glutathione peroxidase 1, 4 (GPx1 and GPx4)) and antioxidant proteins (heme oxygenase-1 (HO-1), superoxide dismutase 1, 2 (SOD1 and SOD2), Γ-glutamylcysteine synthase (Γ-GCSc)) were markedly increased in DOX group compared with the control group, which were significantly attenuated by DATS treatment. The upregulation of antioxidants enzymes in DOX group was probably a compensatory effect against elevated oxidative stress induced by DOX. DATS treatment could ameliorate this oxidative stress in brain. Our results suggested that DATS has potential clinical applications in the prevention of DOX-induced neurotoxicity by ameliorating inflammatory insults and oxidative stress.

Plant-Derived Natural Products in Cancer Research: Extraction, Mechanism of Action, and Drug Formulation

Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.

Bioaccessibility of Bioactive Compounds of 'Fresh Garlic' and 'Black Garlic' through In Vitro Gastrointestinal Digestion

Numerous studies have reported health benefits associated with the consumption of fresh and black garlic, which are characterized by the presence of polyphenols and organosulfur compounds (OS). This study aims to analyze the bioaccessibility of the bioactive compounds in fresh and black garlic after in vitro gastrointestinal digestion by monitoring the individual profile of these compounds by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS). Polyphenols decreased from the beginning of the digestive process, is mainly affected during intestinal digestion. Regarding the OS, the S-alk(en)yl-L-cysteine (SACs) derivatives were more influenced by the acidic conditions of the gastric digestion, while the γ-glutamyl-S-alk(en)yl-L-cysteine (GSAk) derivatives were more susceptible to intestinal digestion conditions in both the fresh and black garlic samples. In conclusion, after in vitro gastrointestinal digestion, the compounds with the highest bioaccessibility were vanillic acid (69%), caffeic acid (52%), γ-glutamyl-S-methyl-L-cysteine sulfoxide (GSMCS) (77%), and S-allylmercapto-L-cysteine (SAMC) (329%) in fresh garlic. Meanwhile, in black garlic, the main bioaccessible compounds were caffeic acid (65%), GSMCS (89%), methionine sulfoxide (262%), trans-S-(1-propenyl)-L-cysteine (151%), and SAMC (106%). The treatment (heating + humidity) to obtain black garlic exerted a positive effect on the bioaccessibility of OS compounds, 55.3% of them remaining available in black garlic, but only 15% in fresh garlic. Polyphenols showed different behavior regarding bioaccessibility.

Pharmacological modulation of the hydrogen sulfide (H2 S) system by dietary H2 S-donors: A novel promising strategy in the prevention and treatment of type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) represents the most common age-related metabolic disorder, and its management is becoming both a health and economic issue worldwide. Moreover, chronic hyperglycemia represents one of the main risk factors for cardiovascular complications. In the last years, the emerging evidence about the role of the endogenous gasotransmitter hydrogen sulfide (H₂ S) in the pathogenesis and progression of T2DM led to increasing interest in the pharmacological modulation of endogenous "H₂ S-system". Indeed, H₂ S directly contributes to the homeostatic maintenance of blood glucose levels; moreover, it improves impaired angiogenesis and endothelial dysfunction under hyperglycemic conditions. Moreover, H₂ S promotes significant antioxidant, anti-inflammatory, and antiapoptotic effects, thus preventing hyperglycemia-induced vascular damage, diabetic nephropathy, and cardiomyopathy. Therefore, H₂ S-releasing molecules represent a promising strategy in both clinical management of T2DM and prevention of macro- and micro-vascular complications associated to hyperglycemia. Recently, growing attention has been focused on dietary organosulfur compounds. Among them, garlic polysulfides and isothiocyanates deriving from Brassicaceae have been recognized as H₂ S-donors of great pharmacological and nutraceutical interest. Therefore, a better understanding of the therapeutic potential of naturally occurring H₂ S-donors may pave the way to a more rational use of these nutraceuticals in the modulation of H₂ S homeostasis in T2DM.

Exploring food contents in scientific literature with FoodMine

Thanks to the many chemical and nutritional components it carries, diet critically affects human health. However, the currently available comprehensive databases on food composition cover only a tiny fraction of the total number of chemicals present in our food, focusing on the nutritional components essential for our health. Indeed, thousands of other molecules, many of which have well documented health implications, remain untracked. To explore the body of knowledge available on food composition, we built FoodMine, an algorithm that uses natural language processing to identify papers from PubMed that potentially report on the chemical composition of garlic and cocoa. After extracting from each paper information on the reported quantities of chemicals, we find that the scientific literature carries extensive information on the detailed chemical components of food that is currently not integrated in databases. Finally, we use unsupervised machine learning to create chemical embeddings, finding that the chemicals identified by FoodMine tend to have direct health relevance, reflecting the scientific community's focus on health-related chemicals in our food.

Antioxidant activity of organic sulfides from fresh Allium macrostemon Bunge and their protective effects against oxidative stress in Caenorhabditis elegans

Long-stamen chive (Allium macrostemon Bunge; AMB), which is prevalent in the Wuling Mountain area of China, is a characteristic food of the nation. In the study, we evaluated the as-yet-unknown nutritional value and antioxidant activity of fresh AMB. The free amino acid content, volatile components, and free radical-scavenging capacity of isolated organic sulfides were analyzed to evaluate the qualitative and physiological properties of fresh AMB. The plant was found to be rich in free essential amino acids and contain multiple flavor-imparting amino acids. The organic sulfides showed an apparent free radical-scavenging activity in vitro. Furthermore, these sulfides alleviated oxidative stress in Caenorhabditis elegans. Notably, the organic sulfides isolated from AMB enhanced the activities of superoxide dismutase, catalase, and glutathione peroxidase; improved motility; and extended the lifespan in oxidative stress-affected nematodes. In conclusion, our study indicates that AMB is a nutritious vegetable with potential to be developed as a functional food. PRACTICAL APPLICATIONS: Long-stamen chive is a wild edible vegetable belonging to the genus Allium (A. macrostemon Bunge; AMB). However, its quality and physiological properties have not been comprehensively investigated. Herein, we analyzed the free amino acid content, composition of volatile compounds, and potential antioxidative properties of AMB. Our results indicated that AMB is rich in essential amino acids, making it a highly nutritious food. Further analysis indicated that AMB contains a high proportion of organic sulfides, which have been previously been shown to have antioxidative properties. Together, our findings indicate that AMB contains important bioactive components and can be developed as a functional food or health supplement. Furthermore, our findings will enhance public awareness regarding this wild resource and provide new directions for the research and development of natural products derived from it.