Garlic constituents for cancer prevention and therapy: From phytochemistry to novel formulations

Effects of Garlic on Breast Tumor Cells with a Triple Negative Phenotype: Peculiar Subtype-Dependent Down-Modulation of Akt Signaling

Breast cancer includes tumor subgroups with morphological, molecular, and clinical differences. Intrinsic heterogeneity especially characterizes breast tumors with a triple negative phenotype, often leading to the failure of even the most advanced therapeutic strategies. To improve breast cancer treatment, the use of natural agents to integrate conventional therapies is the subject of ever-increasing attention. In this context, garlic (Allium sativum) shows anti-cancerous potential, interfering with the proliferation, motility, and malignant progression of both non-invasive and invasive breast tumor cells. As heterogeneity could be at the basis of variable effects, the main objective of our study was to evaluate the anti-tumoral activity of a garlic extract in breast cancer cells with a triple negative phenotype. Established triple negative breast cancer (TNBC) cell lines from patient-derived xenografts (PDXs) were used, revealing subtype-dependent effects on morphology, cell cycle, and invasive potential, correlated with the peculiar down-modulation of Akt signaling, a crucial regulator in solid tumors. Our results first demonstrate that the effects of garlic on TNBC breast cancer are not unique and suggest that only more precise knowledge of the mechanisms activated by this natural compound in each tumor will allow for the inclusion of garlic in personalized therapeutic approaches to breast cancer.

An Overview of the Spices Used for the Prevention and Potential Treatment of Gastric Cancer

Gastric cancer (GC) ranks third in terms of cancer-related deaths and is the fifth most commonly diagnosed type of cancer. Its risk factors include Helicobacter pylori infection, Epstein-Barr virus infection, the consumption of broiled and charbroiled animal meats, salt-preserved and smoke-enhanced foods, alcohol drinking, tobacco smoking, exposure to ionizing radiation, and positive family history. The limited effectiveness of conventional therapies and the widespread risk factors of GC encourage the search for new methods of treatment and prevention. In the quest for cheap and commonly available medications, numerous studies focus on herbal medicine, traditional brews, and spices. In this review, we outline the potential use of spices, including turmeric, ginger, garlic, black cumin, chili pepper, saffron, black pepper, rosemary, galangal, coriander, wasabi, cinnamon, oregano, cardamom, fenugreek, caraway, clove, dill, thyme, Piper sarmentosum, basil, as well as the compounds they contain, in the prevention and treatment of GC. We present the potential molecular mechanisms responsible for the effectivity of a given seasoning substance and their impact on GC cells. We discuss their potential effects on proliferation, apoptosis, and migration. For most of the spices discussed, we also outline the unavailability and side effects of their use.

Investigation of Antiproliferative Effects of Combinations of White and Black Garlic Extracts with 5-Fluorouracil (5-FU) on Caco-2 Colorectal Adenocarcinoma Cells

Garlic is rich in bioactive compounds that are effective against colon cancer cells. This study tests the antioxidant and antiproliferative effects of cold-extracted white and black garlic extracts. Black garlic extracted in water (SSU) exhibits the highest antioxidant activity, phenolic content, and flavonoid content, while black garlic extracted in ethanol (SET) shows the lowest values. Caspase-3 activity is notably higher in the white garlic extracted in methanol (BME), white garlic extracted in methanol combines with 5-FU, black garlic extracted in ethanol (SET), black garlic extracted in ethanol combines with 5-fluorouracil (5-FU), and 5-FU treatments compare to the control group (p > 0.05). BME+5-FU displays the highest caspase-8 activity (p < 0.05). A decrease in NF-κB levels is observed in the SET+5-FU group (p>0.05), while COX-2 activities decrease in the BME, SET+5-FU, SET, and 5-FU groups (p>0.05). Wound healing increases in the BME, BME+5-FU, SET+5-FU, and 5-FU groups (p < 0.05). In conclusion, aqueous black garlic extract may exhibit pro-oxidant activity despite its high antioxidant capacity. It is worth noting that exposure to heat-treated food and increased sugar content may lead to heightened inflammation and adverse health effects. This study is the first to combine garlic with chemo-preventive drugs like 5-FU in Caco-2 cells.

Diallyl trisulfide inhibits osteosarcoma 143B cell migration, invasion and EMT by inducing autophagy

Background

Diallyl trisulfide (DATS), a compound derived from garlic, has been demonstrated its anti-cancer properties. While it has been shown to inhibit the expression of epidermal growth factor receptor (EGFR) in various cancers, its effects on osteosarcoma (OS) cells remain unclear. This study aimed to investigate the impacts of DATS on OS cells growth, migration, invasion, epithelial-mesenchymal transition (EMT) and autophagy, as well as its underlying mechanisms which was involving in the EGFR/PI3K/AKT/mTOR pathway.

Methods

In this study, human osteosarcoma cells (143B) were treated with different concentrations of DATS (10, 50, 100 and 200 μM) for 24 and 48 h, respectively. Cell viability was measured using CCK8, the half lethal concentration was selected for the following experiments. Wound healing and transwell assays were performed to evaluate migration and invasion abilities, while flow cytometry was used to measure apoptosis. Quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting, and confocal imaging were employed to analyze the related mRNA and protein expression levels of epithelial-mesenchymal transition (EMT), EGFR/Phosphoinositide 3 kinase (PI3K)/AKT/Mammalian target of rapamycin (mTOR) signaling pathway and autophagy-related markers.

Results

DATS significantly inhibited proliferation, migration and EMT in osteosarcoma cells. Additionally, DATS promoted cell apoptosis and induced autophagy, which could be rescued by the autophagy inhibitor 3-methyladenine (3-MA). Moreover, DATS treatment led to the inactivation of the EGFR/PI3K/AKT/mTOR pathway in osteosarcoma cells.

Conclusions

This study demonstrated that DATS inhibited osteosarcoma cell growth, migration and EMT, but inducing apoptosis and autophagy. These effects were mediated by the inactivation of the EGFR/PI3K/AKT/mTOR signaling pathway. These findings suggested that DATS could serve as a potential therapeutic agent for osteosarcoma treatment.

Garlic-derived compounds: Epigenetic modulators and their antitumor effects

Cancer is a highly heterogeneous disease that poses a serious threat to human health worldwide. Despite significant advances in the diagnosis and treatment of cancer, the prognosis and survival rate of cancer remain poor due to late diagnosis, drug resistance, and adverse reactions. Therefore, it is very necessary to study the development mechanism of cancer and formulate effective therapeutic interventions. As widely available bioactive substances, natural products have shown obvious anticancer potential, especially by targeting abnormal epigenetic changes. The main active part of garlic is organic sulfur compounds, of which diallyl trisulfide (DATS) content is the highest, accounting for more than 40% of the total composition. The garlic-derived compounds have been recognized as an antioxidant for cancer prevention and treatment. However, the molecular mechanism of the antitumor effect of garlic-derived compounds remains unclear. Recent studies have identified garlic-derived compound DATS that plays critical roles in enhancing CpG demethylation or promoting histone acetylation as an epigenetic inhibitor. Here, we review the therapeutic progress of garlic-derived compounds against cancer through epigenetic pathways.

Revitalizing allicin for cancer therapy: advances in formulation strategies to enhance bioavailability, stability, and clinical efficacy

The main objective of this review is to highlight the therapeutic potential of allicin, a defense molecule in garlic known for its diverse health benefits, and address the key challenges of its bioavailability and stability. The research further aims to evaluate various formulation strategies and nanotechnology-based delivery systems that can resolve these issues and improve allicin's clinical efficacy, especially in cancer therapy. We conducted a comprehensive review of the available literature and previous studies, focusing on the therapeutic properties of allicin, its bioavailability, stability issues, and novel formulation strategies. We assessed the mechanism of action of allicin in cancer, including its effects on signaling pathways, cell cycle, apoptosis, autophagy, and tumor development. We also evaluated the outcomes of both in vitro and in vivo studies on different types of cancers, such as breast, cervical, colon, lung, and gastric cancer. Despite allicin's significant therapeutic benefits, including cardiovascular, antihypertensive, cholesterol-lowering, antimicrobial, antifungal, anticancer, and immune-modulatory activity, its clinical utility is limited due to poor stability and unpredictable bioavailability. Allicin's bioavailability in the gastrointestinal tract is dependent on the activity of the enzyme alliinase, and its stability can be affected by various conditions like gastric acid and intestinal enzyme proteases. Recent advances in formulation strategies and nanotechnology-based drug delivery systems show promise in addressing these challenges, potentially improving allicin's solubility, stability, and bioavailability. Allicin offers substantial potential for cancer therapy, yet its application is hindered by its instability and poor bioavailability. Novel formulation strategies and nanotechnology-based delivery systems can significantly overcome these limitations, enhancing the therapeutic efficacy of allicin. Future research should focus on refining these formulation strategies and delivery systems, ensuring the safety and efficacy of these new allicin formulations. Clinical trials and long-term studies should be carried out to determine the optimal dosage, assess potential side effects, and evaluate their real-world applicability. The comparative analysis of different drug delivery approaches and the development of targeted delivery systems can also provide further insight into enhancing the therapeutic potential of allicin.

Diallyl trisulfide and its active metabolite allyl methyl sulfone attenuate cisplatin-induced nephrotoxicity by inhibiting the ROS/MAPK/NF-κB pathway

Cisplatin, a chemotherapy medication employed in the treatment of various solid tumors, is constrained in its clinical application due to nephrotoxicity. Diallyl trisulfide (DATS), a compound derived from garlic that possessed anticancer and antioxidant properties, can be combined with cisplatin without hindering its antitumor effects. The present investigation examined the defensive properties of DATS and its active metabolites against renal dysfunction caused by cisplatin. We created a mouse model to study renal injury caused by cisplatin and assessed kidney histology, immunochemistry, and serum cytokines. DATS treatment effectively reduced the pathological changes caused by cisplatin by decreasing the levels of renal function markers BUN, CRE, cystatin C, NGAL, inflammatory factors TNF-α, IL-6, and the protein expression of α-SMA, NF-κB, KIM-1. A pharmacokinetic evaluation of DATS found that allyl methyl sulfone (AMSO2) was the most abundant and persistent metabolite of DATS in vivo. Then, we examined the impact of AMSO2 on cell viability, apoptosis, ROS generation, and MAPK/NF-κB pathways in HK-2 cells treated with cisplatin. Cotreatment with AMSO2 effectively hindered the HK-2 cells alterations induced by cisplatin. Furthermore, AMSO2 mitigated oxidative stress through the modulation of MAPK and NF-κB pathways. Our findings indicated that DATS and its active derivative AMSO2 attenuated cisplatin-induced nephrotoxicity. DATS shows potential as a viable treatment for nephrotoxicity caused by cisplatin.

Evidential support for garlic supplements against diabetic kidney disease: a preclinical meta-analysis and systematic review

Garlic (Allium sativum L.) is a popular spice that is widely used for food and medicinal purposes and has shown potential effects on diabetic kidney disease (DKD). Nevertheless, systematic preclinical studies are still lacking. In this meta-analysis and systematic review, we evaluated the role and potential mechanisms of action of garlic and its derived components in animal models of DKD. We searched eight databases for relevant studies from the establishment of the databases to December 2022 and updated in April 2023 before the completion of this review. A total of 24 trials were included in the meta-analysis. It provided preliminary evidence that supplementing with garlic could improve the indicators of renal function (BUN, Scr, 24 h urine volume, proteinuria, and KI) and metabolic disorders (BG, insulin, and body weight). Meanwhile, the beneficial effects of garlic and its components in DKD could be related to alleviating oxidative stress, suppressing inflammatory reactions, delaying renal fibrosis, and improving glucose metabolism. Furthermore, time-dose interval analysis exhibited relatively greater effectiveness when garlic products were supplied at doses of 500 mg kg-1 with interventions lasting 8-10 weeks, and garlic components were administered at doses of 45-150 mg kg-1 with interventions lasting 4-10 weeks. This meta-analysis and systematic review highlights for the first time the therapeutic potential of garlic supplementation in animal models of DKD and offers a more thorough evaluation of its effects and mechanisms to establish an evidence-based basis for designing future clinical trials.

Garlic consumption and colorectal cancer risk in US adults: a large prospective cohort study

Objective

To clarify the inconsistent findings of epidemiological studies on the association between dietary garlic consumption and colorectal cancer (CRC) incidence, by prospectively assessing the association in a large US population.

Methods

Data of 58,508 participants (aged 55-74) from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial were analyzed. Dietary data were collected using a validated questionnaire. Multivariable Cox regression analysis determined hazard ratio (HR) and 95% confidence interval (CI). Restricted cubic spline regression was used to investigate the non-linear relationship, and subgroup analysis was conducted to examine potential effect modifiers.

Results

During a median follow-up of 12.05 years, 782 CRC cases were documented, including 456 proximal colon cancer cases, 322 distal CRC cases, and 4 CRC cases with an unknown site. Moderate dietary garlic consumption was significantly associated with a reduced risk of overall CRC (HRquintile 3vs. 1: 0.70, 95% CI: 0.54 to 0.91, p = 0.007, P for trend: 0.434), exhibiting a U-shaped dose-response pattern, and also with overall CRC in males in the stratified Cox regression model (Model 2: HRquintile 3vs. 1: 0.57, 95% CI: 0.40 to 0.81, p = 0.002), but not in females. The protective association was more pronounced in men, Caucasian, and those with lower alcohol consumption. Notably, these protective effects were observed for overall distal CRC (HRquintile 3vs. 1: 0.62, 95% CI: 0.42 to 0.93, p = 0.021; and HRquintile 4vs. 1: 0.63, 95% CI: 0.43 to 0.92, p = 0.018, P for trend: 0.208); and for distal CRC in males (HRquintile 3vs. 1: 0.40, 95% CI: 0.22 to 0.71, p = 0.002, P for trend: 0.696), but not for proximal CRC.

Conclusion

Moderate consumption of dietary garlic is associated with a decreased CRC risk in the US population, with variations based on CRC anatomic subsites. Further in-depth prospective studies are needed to validate these findings in different populations and to explore subsites-specific associations.

Bioactive phytocompounds for oral cancer prevention and treatment: A comprehensive and critical evaluation

The high incidence of oral cancer combined with excessive treatment cost underscores the need for novel oral cancer preventive and therapeutic options. The value of natural agents, including plant secondary metabolites (phytochemicals), in preventing carcinogenesis and representing expansive source of anticancer drugs have been established. While fragmentary research data are available on antioral cancer effects of phytochemicals, a comprehensive and critical evaluation of the potential of these agents for the prevention and intervention of human oral malignancies has not been conducted according to our knowledge. This study presents a complete and critical analysis of current preclinical and clinical results on the prevention and treatment of oral cancer using phytochemicals. Our in-depth analysis highlights anticancer effects of various phytochemicals, such as phenolics, terpenoids, alkaloids, and sulfur-containing compounds, against numerous oral cancer cells and/or in vivo oral cancer models by antiproliferative, proapoptotic, cell cycle-regulatory, antiinvasive, antiangiogenic, and antimetastatic effects. Bioactive phytochemicals exert their antineoplastic effects by modulating various signaling pathways, specifically involving the epidermal growth factor receptor, cytokine receptors, toll-like receptors, and tumor necrosis factor receptor and consequently alter the expression of downstream genes and proteins. Interestingly, phytochemicals demonstrate encouraging effects in clinical trials, such as reduction of oral lesion size, cell growth, pain score, and development of new lesions. While most phytochemicals displayed minimal toxicity, concerns with bioavailability may limit their clinical application. Future directions for research include more in-depth mechanistic in vivo studies, administration of phytochemicals using novel formulations, investigation of phytocompounds as adjuvants to conventional treatment, and randomized clinical trials.

Prediction of the mechanism for the combination of diallyl trisulfide and cisplatin against gastric cancer: a network pharmacology study and pharmacological evaluation

Background: In this research, we aimed to explore the efficacy of diallyl trisulfide (DATS) combined with cisplatin (DDP) for gastric cancer treatment and its underlying mechanism based on network pharmacology. Methods: First, the pharmacological mechanism by which DATS combined with DDP acts against gastric cancer was predicted using network pharmacology. The TTD, GeneCards, and OMIM databases were used to extract drug and disease targets. The David Bioinformatics Resources 6.8 database was used to conduct GO and KEGG analyses. We investigated the efficacy of DATS combined with DDP against gastric cancer in SGC7901 cells and a xenograft model. Furthermore, the specific mechanism of DATS combined with DDP, inferred by network pharmacology, was identified by Western blotting and immunohistochemistry. Results: The combination of DDP and DATS significantly increased cytotoxicity and cell apoptosis compared to the DATS or DDP treatment group in vitro. In addition, continuous intraperitoneal injection of DATS markedly improved the tumor inhibitory effect of DDP in the SGC-7901 tumor-bearing mouse model. Furthermore, network pharmacology and experimental validation studies revealed that the combination of DATS and DDP synergistically enhanced antitumor activity by regulating endoplasmic reticulum stress and inhibiting STAT3/PKC-δ and MAPK signaling pathways. Conclusion: Our study showed that the combination of DATS and DDP could exert outstanding therapeutic effects in gastric cancer. Moreover, network pharmacology coupled with experimental validation revealed the molecular mechanisms of combination therapy for gastric cancer. This study offers a new adjuvant strategy based on DATS and DDP for the treatment of gastric cancer.

OPTIMIZATION AND CHARACTERIZATION OF ESSENTIAL OILS FORMULATION FOR ENHANCED STABILITY AND DRUG DELIVERY SYSTEM OF MEFLOQUINE

Objective: This work aims to choose suitable essential oil formulations to improve the bioavailability and long-term aqueous stability of mefloquine in drug delivery systems. Methods: Oil phases of pomegranate oil, black cumin seed oil, and garlic oil. To choose the proper oil and surfactant for creating pseudo-ternary phase diagrams, cremophore EL, tween®20 and tween®80 (surfactants), and brij 35 (co-surfactants) were used in a variety of concentrations and combinations (Smix). Mefloquine was estimated to be soluble in a variety of oils, surfactants, and co-surfactants. Drug solubility, drug release research, thermodynamic stability, mean hydrodynamic size and zeta potential. Results: Garlic with smix of cremophore EL and brij 35, Pomegranate with Tween 2.0, and Black cumin seed oil with Tween 80 showed the highest solubilization and emulsification capabilities and were further investigated using ternary phase diagrams. When combined with the co-surfactants under investigation, cremophore EL demonstrated a greater self-emulsification zone than tween® 80 and tween 20. Garlic oil, cremophore EL, and brij 35 nanoemulsion showed smaller size, greater zeta potential, less emulsification time, high transmittance, and better drug solubility than microemulsion formulations on especially those made with tween®20 and tween 80. Mefloquine loaded garlic oil nanoemulsion showed considerably low release in body fluid (32.48%) and a good release in intestinal fluid (82.78%) by 12 h in a drug release study. Conclusion: Garlic oil as the oil phase and a mixture of cremophore EL and brij 35 as the surfactant phase are ideal surfactants and co-surfactant for mefloquine loaded garlic oil nanoemulsion with greater drug release in release kinetics investigation.

Diallyl trisulfide ameliorates bone loss and alters specific gut microbiota and serum metabolites in natural aging mice

Aging is a major cause of bone loss and osteoporosis. Diallyl trisulfide (DATS), one of the main organic sulfides in garlic oil, has been shown to alleviate arthritis in mice. However, further research is still needed to determine how DATS affects bone formation and bone loss in aging mice. Here, we established a mouse model of natural aging for dietary DATS intervention. DATS treatment improved the bone microstructure, including the disorganized arrangement of bone trabeculae and promoted collagen synthesis, as confirmed by micro-CT and histological analyses. The abundance of beneficial bacteria for bone formation, such as Clostridiaceae and Erysipelotrichaceae, and the microbial diversity and community richness were all altered by DATS, according to 16S rRNA sequencing data. 14 potential biomarkers and 9 important metabolic pathways were examined using serum metabolomics analysis. Additionally, there has been a significant reduction in sphingosine, which is directly associated with bone metabolism. The level of sphingosine and relative abundance of Clostridium were found to be negatively correlated by correlation analysis, indicating that bacteria may regulate bone reconstruction via influencing metabolites. Furthermore, Runx2 and β-catenin gene expression levels increased in bones, which may be related to the ameliorative mechanism of DATS. Our results suggested that DATS may prevent age-related bone loss by upregulating osteogenic gene expression through altering gut microbes and serum metabolism.

Changes in the aroma and key odorants from white garlic to black garlic using approaches of molecular sensory science: A review

Black garlic is a relatively new product that has become very popular in recent years. It is obtained by fermenting raw (white) garlic by the application of heat treatment. The undesirable pungent odor of the white garlic disappears and the black garlic product with a sweet-sour flavor is formed after various reactions during the applied heat process. As a result, black garlic is more preferred and easily consumed by the consumers compared to white garlic. This review aims to summarize the studies on the changes in the odorants during the heat treatment employed in the production of black garlic as well as the factors affecting the changes in the aroma and aroma-active compounds and the use of molecular sensory science (MSS) approach, which has been applied in recent years as a new method for the determination of the aroma compounds. This work revealed that the use of the MSS on the aroma changes in black garlic is quite limited in the literature. Thus, more studies are needed to understand the aroma changes that occur during the formation of black garlic from white garlic in more detail.

Natural Polymeric Nanobiocomposites for Anti-Cancer Drug Delivery Therapeutics: A Recent Update

Cancer is one of the most common lethal diseases and the leading cause of mortality worldwide. Effective cancer treatment is a global problem, and subsequent advancements in nanomedicine are useful as substitute management for anti-cancer agents. Nanotechnology, which is gaining popularity, enables fast-expanding delivery methods in science for curing diseases in a site-specific approach, utilizing natural bioactive substances because several studies have established that natural plant-based bioactive compounds can improve the effectiveness of chemotherapy. Bioactive, in combination with nanotechnology, is an exceptionally alluring and recent development in the fight against cancer. Along with their nutritional advantages, natural bioactive chemicals may be used as chemotherapeutic medications to manage cancer. Alginate, starch, xanthan gum, pectin, guar gum, hyaluronic acid, gelatin, albumin, collagen, cellulose, chitosan, and other biopolymers have been employed successfully in the delivery of medicinal products to particular sites. Due to their biodegradability, natural polymeric nanobiocomposites have garnered much interest in developing novel anti-cancer drug delivery methods. There are several techniques to create biopolymer-based nanoparticle systems. However, these systems must be created in an affordable and environmentally sustainable way to be more readily available, selective, and less hazardous to increase treatment effectiveness. Thus, an extensive comprehension of the various facets and recent developments in natural polymeric nanobiocomposites utilized to deliver anti-cancer drugs is imperative. The present article provides an overview of the latest research and developments in natural polymeric nanobiocomposites, particularly emphasizing their applications in the controlled and targeted delivery of anti-cancer drugs.

Thiosulfinates: Cytotoxic and Antitumor Activity

Pharmacological value of some natural compounds makes them attractive for use in oncology. The sulfur-containing thiosulfinates found in plants of the genus Allium have long been known as compounds with various therapeutic properties, including antitumor. Over the last few years, the effect of thiosulfinates on various stages of carcinogenesis has been actively investigated. In vitro and in vivo studies have shown that thiosulfinates inhibit proliferation of cancer cells, as well as they induce apoptosis. The purpose of this review is to summarize current data on the use of natural and synthetic thiosulfinates in cancer therapy. Antitumor mechanisms and molecular targets of these promising compounds are discussed. A significant part of the review is devoted to consideration of a new strategy for treatment of oncological diseases - use of the directed enzyme prodrug therapy approach aiming to obtain antitumor thiosulfinates in situ.

From Natural Sources to Synthetic Derivatives: The Allyl Motif as a Powerful Tool for Fragment-Based Design in Cancer Treatment

Since the beginning of history, natural products have been an abundant source of bioactive molecules for the treatment of different diseases, including cancer. Many allyl derivatives, which have shown anticancer activity both in vitro and in vivo in a large number of cancers, are bioactive molecules found in garlic, cinnamon, nutmeg, or mustard. In addition, synthetic products containing allyl fragments have been developed showing potent anticancer properties. Of particular note is the allyl derivative 17-AAG, which has been evaluated in Phase I and Phase II/III clinical trials for the treatment of multiple myeloma, metastatic melanoma, renal cancer, and breast cancer. In this Perspective, we compile extensive literature evidence with descriptions and discussions of the most recent advances in different natural and synthetic allyl derivatives that could generate cancer drug candidates in the near future.

Comparative Study on the Influence of Various Drying Techniques on Drying Characteristics and Physicochemical Quality of Garlic Slices

Effects of vacuum freeze drying (VFD), air impingement drying (AID), hot air drying based on temperature and humidity control (TH-HAD), pulsed vacuum drying (PVD), and medium- and short-wave infrared radiation drying (MSIRD) on the drying characteristics and physicochemical properties of garlic slices were investigated in the current work. Based on the experimental results, the Weibull model fitted the experimental results better (R2 > 0.99) than the Wang and Singh model. Samples dried with PVD showed the smallest color difference (ΔE*), better rehydration capacity and desirable reducing sugar content. In response to thermal effects and pressure pulsations, the cell walls gradually degraded, and the cell and organelle membranes ruptured. The allicin and soluble pectin contents of garlic slices treated with PVD were higher by 8.0–252.3% and 49.5–92.2%, respectively, compared to those of the samples dried by other techniques. VFD maintained a complete garlic slice structure with the minimum shrinkage and the best appearance. The MSIRD process produced the densest structure, and caused an additional loss of color and phytochemical contents. The findings in current work implied that PVD could be a promising drying technique for garlic slices.

Updates on the anticancer potential of garlic organosulfur compounds and their nanoformulations: Plant therapeutics in cancer management

Garlic (Allium sativum L.) possesses numerous pharmacological potential, including antibacterial, antiarthritic, antithrombotic, anticancer, hypoglycemic, and hypolipidemic effects. The anti-cancer action of garlic is likely the best researched of the many advantageous pharmacological effects, and its use offers significant protection against the risk of developing cancer. A few active metabolites of garlic have been reported to be essential in the destruction of malignant cells due to their multi-targeted activities and lack of significant toxicity. The bioactive compounds in garlic having anticancer properties include diallyl trisulfide, allicin, allyl mercaptan diallyl disulfide, and diallyl sulphide. Different garlic-derived constituents and their nanoformulations have been tested for their effects against various cancers including skin, ovarian, prostate, gastric, breast, and lung, colorectal, liver, oral, and pancreatic cancer. The objective of this review is to summarize the antitumor activity and associated mechanisms of the organosulfur compounds of garlic in breast carcinoma. Breast cancer continues to have a significant impact on the total number of cancer deaths worldwide. Global measures are required to reduce its growing burden, particularly in developing nations where incidence is increasing quickly and fatality rates are still high. It has been demonstrated that garlic extract, its bioactive compounds, and their use in nanoformulations can prevent breast cancer in all of its stages, including initiation, promotion, and progression. Additionally, these bioactive compounds affect cell signaling for cell cycle arrest and survival along with lipid peroxidation, nitric oxide synthase activity, epidermal growth factor receptor, nuclear factor kappa B (NF-κB), and protein kinase C in breast carcinoma. Hence, this review deciphers the anticancer potential of garlic components and its nanoformulations against several breast cancer thereby projecting it as a potent drug candidate for efficient breast cancer management.

The Effect of Different Storage Conditions on Phytochemical Composition, Shelf-Life, and Bioactive Compounds of Voghiera Garlic PDO

Voghiera garlic is an Italian white garlic variety which obtained in 2010 the Protected Designation of Origin. It is widely used for culinary purposes or as an ingredient for supplement production due to its phytochemical compositions. The storage conditions seem to be crucial to retain the high quality of garlic bulbs and their by-products, taking into account the high importance of organosulfur and phenolic compounds for the bioactive potency of garlic and its shelf-life. This study aims to examine the effect of storage on the phytochemical composition, biological effects, and shelf-life of Voghiera garlic PDO. In detail, we considered (i) -4 °C (industrial storage) for 3, 6, and 9 months; (ii) +4 °C for 3 months (home conservation), and (iii) -4 °C for 3 months, plus +4 °C for another 3 months. We focused our attention on the organosulfur compounds, total condensed tannins, flavonoids, phenolic compounds, and related antioxidant activity changes during the storage period. To evaluate the bioactive effects, the Voghiera garlic extracts at different storage conditions were administered to a breast cancer cell line, while antioxidant and anti-inflammatory activity was detected using macrophage RAW 264.7 cells. We observed a decrease in sulfur compounds after 6 months which correlated to a decrease in bioactive effects, while the number of antioxidant compounds was stable during the storage period, showing the good effect of refrigerated temperature in maintaining garlic bulb shelf-life.

Targeting lipid metabolism with natural products: A novel strategy for gastrointestinal cancer therapy

Gastrointestinal cancer (GIC), including gastric cancer and colorectal cancer, is a common malignant tumor originating from gastrointestinal epithelial cells. Although the pathogenesis of GIC remains unclear, aberrant lipid metabolism has emerged as a hallmark of cancer. Several enzymes, proteins, and transcription factors are involved in lipid metabolism reprogramming in GIC, and their abnormal expression can promote lipid synthesis and accumulation of lipid droplets through numerous mechanisms, thereby affecting the growth, proliferation, and metastasis of GIC cells. Studies show that some natural compounds, including flavonoids, alkaloids, and saponins, can inhibit the de novo synthesis of lipids in GIC, reduce the level of lipid accumulation, and subsequently, inhibit the occurrence and development of GIC by regulating Sterol regulatory element-binding protein 1 (SREBP-1), adenosine monophosphate-activated protein kinase (AMPK), 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR), phosphatidylinositol-3-kinase/Akt and the mammalian target of rapamycin PI3K/Akt/mTOR, amongst other targets and pathways. Therefore, targeting tumor lipid metabolism is the focus of anti-gastrointestinal tumor therapy. Although most natural products require further high-quality studies to firmly establish their clinical efficacy, we review the potential of natural products in the treatment of GIC and summarize the application prospect of lipid metabolism as a new target for the treatment of GIC, hoping to provide a reference for drug development for gastrointestinal tumors.

Novel Strategies for the Bioavailability Augmentation and Efficacy Improvement of Natural Products in Oral Cancer

Oral cancer is emerging as a major cause of mortality globally. Oral cancer occupies a significant proportion of the head and neck, including the cheeks, tongue, and oral cavity. Conventional methods in the treatment of cancer involve surgery, radiotherapy, and immunotherapy, and these have not proven to completely eradicate cancerous cells, may lead to the reoccurrence of oral cancer, and possess numerous adverse side effects. Advancements in novel drug delivery approaches have gained popularity in cancer management with an increase in the number of cases associated with oral cancer. Natural products are potent sources for drug discovery, especially for anticancer drugs. Natural product delivery has major challenges due to its low solubility, poor absorption, inappropriate size, instability, poor permeation, and first-pass metabolism. Therefore, it is of prime importance to investigate novel treatment approaches for the delivery of bioactive natural products. Nanotechnology is an advanced method of delivering cancer therapy with minimal damage to normal cells while targeting cancer cells. Therefore, the present review elaborates on the advancements in novel strategies for natural product delivery that lead to the significant enhancement of bioavailability, in vivo activity, and fewer adverse events for the prevention and treatment of oral cancer. Various approaches to accomplish the desired results involve size reduction, surface property modification, and polymer attachment, which collectively result in the higher stability of the formulation.

Chemical Composition, Antimicrobial and Antioxidant Activity of Essential Oil from Allium tenuissimum L. Flowers

Allium tenuissimum L. as a kind of food condiment in northern China, is popular among more and more consumers owning to its special flavor from the flower. However, its composition has not been widely studied. Hence, the aim of this study was to investigate the chemical composition and antimicrobial and antioxidant activity of essential oil from Allium tenuissimum L. flowers. Gas chromatography−mass spectrometry (GC-MS) was applied to detect the chemical composition. The antimicrobial activity against foodborne pathogens was evaluated by measuring the zones of inhibition (ZOI), the minimal inhibitory concentration (MIC), and the minimal bactericidal concentration (MBC). The antioxidant effect was tested by the scavenging capacity on DPPH, ABTS+•, and •OH. The results of GC-MS showed that 72 volatile components were isolated and the structures 68 of them were identified, which comprised about 91.92% of the total composition of the oil. Among these compounds, terpenoid compounds and sulfurous compounds had the highest contents, especially dimethyl trisulfide. Our investigation demonstrated that the essential oil has better antimicrobial efficiency to Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Aspergillus flavus, and Saccharomyces cerevisiae. In addition, the essential oil had a strong stability to UV. Furthermore, the essential oil exhibited a high radical-scavenging effect on DPPH, ABTS+•, and •OH, which is significant for application in the food industry. In conclusion, the essential oil could be used as an inexpensive and natural antibacterial and antioxidant agent in food.

Spice-Derived Bioactive Compounds Confer Colorectal Cancer Prevention via Modulation of Gut Microbiota

Colorectal cancer (CRC) is the second most frequent cause of cancer-related mortality among all types of malignancies. Sedentary lifestyles, obesity, smoking, red and processed meat, low-fiber diets, inflammatory bowel disease, and gut dysbiosis are the most important risk factors associated with CRC pathogenesis. Alterations in gut microbiota are positively correlated with colorectal carcinogenesis, as these can dysregulate the immune response, alter the gut's metabolic profile, modify the molecular processes in colonocytes, and initiate mutagenesis. Changes in the daily diet, and the addition of plant-based nutraceuticals, have the ability to modulate the composition and functionality of the gut microbiota, maintaining gut homeostasis and regulating host immune and inflammatory responses. Spices are one of the fundamental components of the human diet that are used for their bioactive properties (i.e., antimicrobial, antioxidant, and anti-inflammatory effects) and these exert beneficial effects on health, improving digestion and showing anti-inflammatory, immunomodulatory, and glucose- and cholesterol-lowering activities, as well as possessing properties that affect cognition and mood. The anti-inflammatory and immunomodulatory properties of spices could be useful in the prevention of various types of cancers that affect the digestive system. This review is designed to summarize the reciprocal interactions between dietary spices and the gut microbiota, and highlight the impact of dietary spices and their bioactive compounds on colorectal carcinogenesis by targeting the gut microbiota.

Nutraceutical-Based Nanoformulations for Breast and Ovarian Cancer Treatment

Different strategies have been investigated for a more satisfactory treatment of advanced breast cancer, including the adjuvant use of omega-3 polyunsaturated fatty acids (PUFAs). These nutritional compounds have been shown to possess potent anti-inflammatory and antiangiogenic activities, the capacity to affect transduction pathways/receptors involved in cell growth and to reprogram tumor microenvironment. Omega-3 PUFA-containing nanoformulations designed for drug delivery in breast cancer were shown to potentiate the effects of enclosed drugs, enhance drug delivery to target sites, and minimize drug-induced side effects. We have critically analyzed here the results of the most recent studies investigating the effects of omega-3 PUFA-containing nanoformulations in breast cancer. The anti-neoplastic efficacy of omega-3 PUFAs has also been convincingly demonstrated by using preclinical in vivo models of ovarian cancer. The results obtained are critically analyzed here and seem to provide a sufficient rationale to move to still lacking interventional clinical trials, as well as to evaluate possible advantages of enclosing omega-3 PUFAs to drug-delivery nanosystems for ovarian cancer. Future perspectives in this area are also provided.

Evaluation of Antioxidant, Cytotoxic and Antidiabetic Effects of Single Bulb Black Garlic Extracts

Amaç: Allium sativum L. (Sarımsak) bitkisinin belli bir derecede nem ve sıcaklık ile işlem görmesi sonucu, elde edilen fermente ürün tek diş siyah sarımsağın biyoaktivitesinin tespit edilmesi amaçlandı.Yöntem: Çalışmada, siyah sarımsak dişlerinin etanol ve su ekstresi hazırlandı, yine ayrılan kabuk kısımları da etanol ile ekstre edilerek, DPPH● ve ABTS●+ radikalini süpürücü etki tayin yöntemi ile antioksidan aktivitesi değerlendirildi. In vitro α-amilaz inhibisyon testi ile antidiyabetik aktivitesi belirlendi. MTT yöntemi kullanılarak ekstrelerin Colo-205 hücrelerinde sitotoksik etkisi tayin edildi.Bulgular: Siyah sarımsak ekstrelerinden kabuk ekstresi (A.S.K EtOH) en yüksek toplam fenol (61,40±0,48 mgGA/gekstre) ve toplam flavonoit (26,08±0,37 mgCA/gekstre) içeriğine sahip ekstre olarak tespit edildi. Ayrıca, 4mg/mL konsantrasyonda A.S. SU ekstresi DPPH● radikalini süpürücü aktivitesi (% inhibisyonu 64,66±1,94) en yüksek ekstre olarak tespit edilirken, A.S.K EtOH ekstresi 4mg/mL’de ABTS radikalini süpürücü aktivitesi en yüksek ekstre (2,44±0,16mmol/L/Trolox) olarak bulundu. İnsan kolorektal kanser hücre hattı Colo-205’te sitotoksik etkisi değerlendirilen ekstrelerden, S.K EtOH ekstresinin 1000-250 µg/mL konsantrasyon aralığında diğer ekstrelere oranla en fazla sitotoksik etki gösteren ekstre olduğu belirlendi. Ekstrelerden hiçbiri akarbozun pozitif kontrol olarak kullanıldığı α-amilaz inhibiyon testine göre antidiyabetik aktivite gösteremedi.Sonuç: Sonuçlar son yıllarda oldukça popüler olan siyah sarımsağın biyolojik aktivitelerine dair ön çalışma verileridir. Elde edilen verilere göre siyah sarımsağın aktif bileşenlerinin daha detaylı bir şekilde çalışılması ve siyah sarımsak elde etme ve saklama yöntemlerinin daha detaylı araştırılması gerekmektedir. Böylelikle tıbbi açıdan oldukça büyük öneme sahip bir bitkinin fermente halinin kullanımı ve faydaları ile ilgili umut vaat edici sonuçlar elde edilebilir.

Diallyl Trisulfide Prevents Adipogenesis and Lipogenesis by Regulating the Transcriptional Activation Function of KLF15 on PPARγ to Ameliorate Obesity

SCOPE

Diallyl trisulfide (DATS) is a bioactive compound in garlic. The anti-obesity effect of garlic oil has been reported, but the role and mechanism of DATS in preventing obesity remain to be explored.

METHODS AND RESULTS

We performed studies with high-fat-diet-induced obese mice and 3T3-L1 adipocytes. The results showed that DATS significantly reduced lipid accumulation and repaired disordered metabolism in vivo by restraining adipogenesis and lipogenesis, and promoting lipolysis and fatty acid oxidation in white adipose tissue. In cells, DATS played different roles at different stages of adipocyte differentiation. Notably, DATS reduced lipid accumulation mainly by inhibiting adipogenesis and lipogenesis at the late stage. KLF15 was knocked down in 3T3-L1 cells, which eliminated the inhibitory effect of DATS on adipogenesis and lipogenesis. The dual-luciferase reporter and ChIP assays indicated that DATS could inhibit the transcriptional activation function of KLF15 on PPARγ by inhibiting the binding of KLF15 to PPARγ promoter. The function comparison of structural analogs and the intervention of dithiothreitol showed that disulfide bond was crucial for DATS to work.

CONCLUSION

DATS prevents obesity by regulating the transcriptional activation function of KLF15 on PPARγ. This article is protected by copyright. All rights reserved.

Accumulation of Sulforaphane and Alliin in Human Prostate Tissue

Diets rich in cruciferous vegetables have been associated with a lower risk of incidence and progression of prostate cancer. Sulforaphane, an isothiocyanate derived from 4-methylsulphinylbutyl glucosinolate (glucoraphanin) that accumulates in certain of these vegetables, notably broccoli, has been implicated in their protective effects. Likewise, the consumption of garlic and its sulphur-containing compounds such as alliin have been associated with a reduction in risk of prostate cancer. In this study, we tested whether consuming glucoraphanin derived from broccoli seeds and alliin derived from garlic resulted in the occurrence of these potential bioactive compounds in the prostate, which may contribute to our understanding of the putative protective effects of these dietary components. We recruited 42 men scheduled for a trans-perineal prostate biopsy into a randomised, double-blinded, 2 × 2-factorial dietary supplement four-week intervention study, and 39 completed the study. The two active interventions were supplements providing glucoraphanin from broccoli (BroccoMax®) and alliin from garlic (Kwai Heartcare®). Following the intervention, prostate biopsy tissue was analysed for the presence of sulforaphane and its thiol conjugates and for alliin and associated metabolites. Sulforaphane occurred in significantly higher levels in the prostate tissue (both within the transition and peripheral zone) of men consuming the glucoraphanin containing supplements (p < 0.0001) compared to men not consuming these supplements. However, while alliin and alliin-derived metabolites were detected within the prostate, there was no significant difference in the concentrations of these compounds in the prostate of men consuming supplements derived from garlic compared to men not consuming these supplements.

Phytochemicals for the Prevention and Treatment of Renal Cell Carcinoma: Preclinical and Clinical Evidence and Molecular Mechanisms

Simple Summary

Renal cell carcinoma (RCC) is the most frequently diagnosed kidney cancer. Once RCC metastasizes, successful treatment is difficult to achieve. There is an apparent need for novel approaches to prevent and treat RCC. Phytochemicals are naturally derived compounds gaining increasing scientific interest due to their cancer preventive and chemotherapeutic properties. These phytochemicals have been shown to exhibit a multitude of anticancer effects against RCC. In this systematic review, we critically evaluate the potential these natural compounds possess for the prevention and treatment of RCC and discuss the future implications this may have in the fight against kidney cancer.

Abstract

Renal cell carcinoma (RCC) is associated with about 90% of renal malignancies, and its incidence is increasing globally. Plant-derived compounds have gained significant attention in the scientific community for their preventative and therapeutic effects on cancer. To evaluate the anticancer potential of phytocompounds for RCC, we compiled a comprehensive and systematic review of the available literature. Our work was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. The literature search was performed using scholarly databases such as PubMed, Scopus, and ScienceDirect and keywords such as renal cell carcinoma, phytochemicals, cancer, tumor, proliferation, apoptosis, prevention, treatment, in vitro, in vivo, and clinical studies. Based on in vitro results, various phytochemicals, such as phenolics, terpenoids, alkaloids, and sulfur-containing compounds, suppressed cell viability, proliferation and growth, showed cytotoxic activity, inhibited invasion and migration, and enhanced the efficacy of chemotherapeutic drugs in RCC. In various animal tumor models, phytochemicals suppressed renal tumor growth, reduced tumor size, and hindered angiogenesis and metastasis. The relevant antineoplastic mechanisms involved upregulation of caspases, reduction in cyclin activity, induction of cell cycle arrest and apoptosis via modulation of a plethora of cell signaling pathways. Clinical studies demonstrated a reduced risk for the development of kidney cancer and enhancement of the efficacy of chemotherapeutic drugs. Both preclinical and clinical studies displayed significant promise of utilizing phytochemicals for the prevention and treatment of RCC. Further research, confirming the mechanisms and regulatory pathways, along with randomized controlled trials, are needed to establish the use of phytochemicals in clinical practice.

Herb and Spices in Colorectal Cancer Prevention and Treatment: A Narrative Review

Colorectal cancer (CRC) is the second most deadly cancer worldwide. CRC management is challenging due to late detection, high recurrence rate, and multi-drug resistance. Herbs and spices used in cooking, practised for generations, have been shown to contain CRC protective effect or even be useful as an anti-CRC adjuvant therapy when used in high doses. Herbs and spices contain many bioactive compounds and possess many beneficial health effects. The chemopreventive properties of these herbs and spices are mainly mediated by the BCL-2, K-ras, and MMP pathways, caspase activation, the extrinsic apoptotic pathway, and the regulation of ER-stress-induced apoptosis. As a safer natural alternative, these herbs and spices could be good candidates for chemopreventive or chemotherapeutic agents for CRC management because of their antiproliferative action on colorectal carcinoma cells and inhibitory activity on angiogenesis. Therefore, in this narrative review, six different spices and herbs: ginger (Zingiber officinale Roscoe), turmeric (Curcuma longa L.), garlic (Allium sativum L.), fenugreek (Trigonella foenum-graecum L.), sesame (Sesamum indicum L.), and flaxseed (Linum usitatissimum L.) used in daily cuisine were selected for this study and analyzed for their chemoprotective or chemotherapeutic roles in CRC management with underlying molecular mechanisms of actions. Initially, this study comprehensively discussed the molecular basis of CRC development, followed by culinary and traditional uses, current scientific research, and publications of selected herbs and spices on cancers. Lead compounds have been discussed comprehensively for each herb and spice, including anti-CRC phytoconstituents, antioxidant activities, anti-inflammatory properties, and finally, anti-CRC effects with treatment mechanisms. Future possible works have been suggested where applicable.

The effect of calycosin-7-O-β-D-glucoside and its synergistic augmentation of cisplatin-induced apoptosis in SK-OV-3 cells

OBJECTIVE

This study aims to examine the synergetic augmentation of calycosin-7-O-β-D-glucoside (CG) on cisplatin (CDDP) to induce apoptosis of human epithelial ovarian SK-OV-3 cancer cells.

METHODS

The SK-OV-3 cells were divided into four groups: control, CDDP monotherapy, CG monotherapy, and combined CDDP and CG treatment. The cell counting kit-8 method was used to detect cell proliferation at different times and under different treatments. Hoechst 33258 staining and annexin V-FITC/propidium iodide double staining methods were used to observe the apoptosis of the SK-OV-3 cells. The caspase-3 enzyme activity detection method, quantitative reverse transcription-polymerase chain reaction, and western blot were used to detect the apoptosis-related factors and the activities of the enzyme in SK-OV-3 cells.

RESULTS

The inhibition rates of SK-OV-3 cell proliferation when exposed to 10 μM of CDDP, 50 μM of CG, and a combination of 10 μM of CDDP and 50 μM of CG were 23.2% ± 1.1%, 26.7% ± 2.0%, and 46.7% ± 1.3% after 48 h, respectively. Following the use of the drug combination, the apoptosis rate and caspase-3 enzyme activity were significantly higher than in the single-drug treatment group; in addition, the data differences were significant (p < 0.05). At the protein and ribonucleic acid levels, CG significantly enhanced the effect of CDDP on p53, caspase-3, caspase-9, Bax, and Bcl-2.

CONCLUSION

In vitro, CG significantly increases the CDDP-induced apoptosis of the SK-OV-3 cells through the p53 pathway at the cellular level. In addition, using the drugs in combination reduces the toxicity and side effects caused by using CDDP alone.

Current studies and potential future research directions on biological effects and related mechanisms of allicin

Allicin, a thiosulfonate extract from freshly minced garlic, has been reported to have various biological effects on different organs and systems of animals and human. It can reduce oxidative stress, inhibit inflammatory response, resist pathogen infection and regulate intestinal flora. In addition, dozens of studies also demonstrated allicin could reduce blood glucose level, protect cardiovascular system and nervous system, and fight against cancers. Allicin was widely used in disease prevention and health care. However, more investigations on human cohort study are needed to verify the biological or clinical effects of allicin in the future. In this review, we summarized the biological effects of allicin from previous outstanding and valuable studies and provided useful information for future studies on the health effects of allicin.

Molecular Functions of Hydrogen Sulfide in Cancer

Hydrogen sulfide (H₂S) is a gasotransmitter that exerts a multitude of functions in both physiologic and pathophysiologic processes. H₂S-synthesizing enzymes are increased in a variety of human malignancies, including colon, prostate, breast, renal, urothelial, ovarian, oral squamous cell, and thyroid cancers. In cancer, H₂S promotes tumor growth, cellular and mitochondrial bioenergetics, migration, invasion, angiogenesis, tumor blood flow, metastasis, epithelia–mesenchymal transition, DNA repair, protein sulfhydration, and chemotherapy resistance Additionally, in some malignancies, increased H₂S-synthesizing enzyme expression correlates with a worse prognosis and a higher tumor stage. Here we review the role of H₂S in cancer, with an emphasis on the molecular mechanisms by which H₂S promotes cancer development, progression, dedifferentiation, and metastasis.