Allicin induces apoptosis in EL-4 cells in vitro by activation of expression of caspase-3 and -12 and up-regulation of the ratio of Bax/Bcl-2

Natural Extracts for Antibacterial Applications

Bacteria-induced epidemics and infectious diseases are seriously threatening the health of people around the world. In addition, antibiotic therapy has been inducing increasingly more serious bacterial resistance, which makes it urgent to develop new treatment strategies to combat bacteria, including multidrug-resistant bacteria. Natural extracts displaying antibacterial activity and good biocompatibility have attracted much attention due to greater concerns about the safety of synthetic chemicals and emerging drug resistance. These antibacterial components can be isolated and utilized as antimicrobials, as well as transformed, combined, or wrapped with other substances by using modern assistive technologies to fight bacteria synergistically. This review summarizes recent advances in natural extracts from three kinds of sources-plants, animals, and microorganisms-for antibacterial applications. This work discusses the corresponding antibacterial mechanisms and the future development of natural extracts in antibacterial fields.

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.

Protective Effects of Allicin on ISO-Induced Rat Model of Myocardial Infarction via JNK Signaling Pathway

OBJECTIVE

This research was aimed to explore protective effects of allicin on rat model of myocardial infarction via JNK signaling pathway.

METHODS

Rat myocardial ischemia model was established with subcutaneous injection of isoproterenol (ISO). Seventy-five rats were randomly divided into 5 groups (n = 15): sham group, ISO group, low-dose group (1.2 mg/kg/days for 7 days), medium-dose group (1.8 mg/kg/days for 7 days), and high-dose group (3.6 mg/kg/days for 7 days). Routine HE staining and Masson staining were performed to observe myocardial histopathology. The expression of oxidative stress-related indicators, heart tissue apoptosis-related proteins, and JNK and p-JNK proteins were measured for different groups.

RESULTS

Compared with the sham group, the T wave value of the ISO group was significantly increased (p < 0.01). When allicin was administered, the T wave values at different time points in all groups were all decreased. Compared with the sham group, the ratio of eNOS, Bcl-2/Bax was significantly decreased, and p-eNOS, iNOS, caspase-3, caspase-9, and Cyt-c were significantly elevated in the ISO group (p < 0.05). After allicin was administered, significant changes in these proteins were observed in the medium- and high-dose groups. There was no significant change in the expression of JNK protein in the ISO group compared with the sham group; however, the expression of eNOS and p-JNK protein were significantly upregulated (p < 0.01) and the expression of p-eNOS and iNOS were significantly downregulated (p < 0.01). When allicin was administered, expression of p-JNK protein was significantly downregulated.

CONCLUSION

Allicin can reduce oxidative stress damage and cardiomyocyte apoptosis in rat model of myocardial infarction and can significantly regulate JNK signaling pathway.

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

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

Molecular mechanism and cytotoxicity of allicin and all-trans retinoic acid against CD44+ versus CD117+ melanoma cells

BACKGROUND

All-trans retinoic acid (ATRA) is a differentiating agent that inhibits cancer cell growth during the cell cycle. However, despite its potent antitumor properties, some melanoma cells are resistant to ATRA therapy.

PURPOSE

Here, we hypothesized that allicin can sensitize malignant melanoma cells to ATRA treatment. To clarify this mechanism, we determined the sensitivity to ATRA, allicin and allicin/ATRA in CD44⁺ and CD117⁺ melanoma cell subpopulations.

METHODS

The CD44⁺and CD117⁺cells were sorted from A375 melanoma cell line using the magnetic-activated cell sorting (MACS). The potential anticancer effects of ATRA, allicin and allicin/ATRA were examined using cell proliferation MTT assay. In addition, flow cytometry was used to detect cell cycle arrest. The efficacy of the treatments in controlling cancer cell proliferation was assessed by quantitative realtime polymerase chain reaction (RT-PCR).

RESULTS

Here, we demonstrated that CD44⁺ melanoma cells were more resistant to allicin and ATRA than CD117⁺ cells. Importantly, we observed that allicin sensitized melanoma cell to ATRA-induced cell death. The combination treatment with allicin and ATRA significantly reduced the IC₅₀ value obtained for ATRA alone in CD44⁺ melanoma cells. In CD44⁺ cells, the IC₅₀ value of ATRA was 37.43 ± 0.54, while the IC₅₀ value of allicin/ATRA treatment was 17.53 ± 0.2 µM. Allicin treatment resulted in significant increases in the percentage of cells at the G2/M and G0/G1 phases in the CD44⁺ and CD117⁺ cells, respectively. The combination treatment caused the inhibition of CD44⁺ and CD117⁺ melanoma cells at the S phases compared to ATRA alone. Allicin, ATRA, and allicin/ATRA increased the expression of cyclin D1 mRNA in both CD44⁺ and CD117⁺ cells. Allicin combination with ATRA increased the mRNA level of RARβ in CD117⁺ cells. Furthermore, allicin alone caused a remarkable reduction of MMP-9 mRNA expression in both CD44⁺ and CD117⁺ cells. In contrast, ATRA and the combination treatment significantly increased MMP-9 gene expression in CD44⁺ cells.

CONCLUSION

Overall, our results indicate that allicin reinforces the ATRA-mediated inhibitory effects on CD44⁺ and CD117⁺ melanoma cells and may provide a new approach for the treatment of malignant melanoma.

Synthesis and in vitro biological evaluation of thiosulfinate derivatives for the treatment of human multidrug-resistant breast cancer

Organosulfur compounds derived from Allium vegetables have long been recognized for various therapeutic effects, including anticancer activity. Allicin, one of the main biologically active components of garlic, shows promise as an anticancer agent; however, instability makes it unsuitable for clinical application. The aim of this study was to investigate the effect of stabilized allicin derivatives on human breast cancer cells in vitro. In this study, a total of 22 stabilized thiosulfinate derivatives were synthesized and screened for their in vitro antiproliferative activities against drug-sensitive (MCF-7) and multidrug-resistant (MCF-7/Dx) human adenocarcinoma breast cancer cells. Assays for cell death, apoptosis, cell cycle progression and mitochondrial bioenergetic function were performed. Seven compounds (4b, 7b, 8b, 13b, 14b, 15b and 18b) showed greater antiproliferative activity against MCF-7/Dx cells than allicin. These compounds were also selective towards multidrug-resistant (MDR) cells, a consequence attributed to collateral sensitivity. Among them, 13b exhibited the greatest anticancer activity in both MCF-7/Dx and MCF-7 cells, with IC₅₀ values of 18.54±0.24 and 46.50±1.98 μmol/L, respectively. 13b altered cellular morphology and arrested the cell cycle at the G₂/M phase. Additionally, 13b dose-dependently induced apoptosis, and inhibited cellular mitochondrial respiration in cells at rest and under stress. MDR presents a significant obstacle to the successful treatment of cancer clinically. These results demonstrate that thiosulfinate derivatives have potential as novel anticancer agents and may offer new therapeutic strategies for the treatment of chemoresistant cancers.

Garlic ((Allium sativum)) Fresh Juice Induces Apoptosis in Human Oral Squamous Cell Carcinoma: The Involvement of Caspase-3, Bax and Bcl-2

Background and aims. There is no report on the apoptotic impact of Allium sativum L.(Garlic) on the oral squamous cell carcinoma (KB); hence, this study was designed to survey the apoptotic effects of garlic fresh juice (GFJ) on the KB cells. Materials and methods. MTTassay (MicrocultureTetrazolium Assay) was carried out to evaluate the cytotoxicity of GFJ on KB cells. Furthermore, TUNEL(Terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling)and DNA fragmentation tests were performed to determine if GFJ is able to induce apoptosis in KB cells. Also a standard kit was used to assess caspase-3 activity in KB cells. Also western blotting was employed to evaluate the effect of GFJ on Bax:Bcl-2 ratio. Results. Significant cytotoxic effects were observed for the minimum used concentration (1μg/mL) as calculated to be 77.97±2.3% for 24 h and 818±3.1% for 36h of incubation (P < 0.001). Furthermore, TUNEL and DNA fragmentation tests corroborated the apoptosis inducing activity of GFJ. Consistently, after treating KB cells with GFJ(1μg/mL), caspase-3 activity and Bax:Bcl-2 ratio were raised by 7.3±0.6 and (P <0.001) folds, respectively. Conclusion. The results of this study advanced that GFJ induces apoptosis in the KB cells through increasing caspase-3 activity and Bax:Bcl2 ratio which could be attributed to its organo-sulfurcomponents.

Research Advances on Pathways of Nickel-Induced Apoptosis

High concentrations of nickel (Ni) are harmful to humans and animals. Ni targets a number of organs and produces multiple toxic effects. Apoptosis is important in Ni-induced toxicity of the kidneys, liver, nerves, and immune system. Apoptotic pathways mediated by reactive oxygen species (ROS), mitochondria, endoplasmic reticulum (ER), Fas, and c-Myc participate in Ni-induced cell apoptosis. However, the exact mechanism of apoptosis caused by Ni is still unclear. Understanding the mechanism of Ni-induced apoptosis may help in designing measures to prevent Ni toxicity.

Use of dietary phytochemicals to target inflammation, fibrosis, proliferation, and angiogenesis in uterine tissues: promising options for prevention and treatment of uterine fibroids?

Uterine leiomyomas (fibroids, myomas) are the most common benign tumors of female reproductive tract. They are highly prevalent, with 70-80% of women burdened by the end of their reproductive years. Fibroids are a leading cause of pelvic pain, abnormal vaginal bleeding, pressure on the bladder, miscarriage, and infertility. They are the leading indication for hysterectomy, and costs exceed 6 billion dollars annually in the United States. Unfortunately, no long-term medical treatments are available. Dysregulation of inflammatory processes are thought to be involved in the initiation of leiomyoma and extracellular matrix deposition, cell proliferation, and angiogenesis are the key cellular events implicated in leiomyoma growth. In modern pharmaceutical industries, dietary phytochemicals are used as source of new potential drugs for many kinds of tumors. Dietary phytochemicals may exert therapeutic effects by interfering with key cellular events of the tumorigenesis process. At present, a negligible number of phytochemicals have been tested as therapeutic agents against fibroids. In this context, our aim was to introduce some of the potential dietary phytochemicals that have shown anti-inflammatory, antiproliferative, antifibrotic, and antiangiogenic activities in different biological systems. This review could be useful to stimulate the evaluation of these phytochemicals as possible therapies for uterine fibroids.

The synergistic anticancer effect of artesunate combined with allicin in osteosarcoma cell line in vitro and in vivo

BACKGROUND

Artesunate, extracted from Artemisia annua, has been proven to have anti-cancer potential. Allicin, diallyl thiosulfinate, the main biologically active compound derived from garlic, is also of interest in cancer treatment research. This object of this report was to document synergistic effects of artesunate combined with allicin on osteosarcoma cell lines in vitro and in vivo.

METHODS

After treatment with artesunate and allicin at various concentrations, the viability of osteosarcoma cells was analyzed by MTT method, with assessment of invasion and motility, colony formation and apoptosis. Western Blotting was performed to determine the expression of caspase-3/9, and activity was also detected after drug treatment. Moreover, in a nude mouse model established with orthotopic xenograft tumors, tumor weight and volume were monitored after drug administration via the intraperitoneal (i.p.) route.

RESULTS

The viability of osteosarcoma cells in the combination group was significantly decreased in a concentration and time dependent manner; moreover, invasion, motility and colony formation ability were significantly suppressed and the apoptotic rate was significantly increased through caspase-3/9 expression and activity enhancement in the combination group. Furthermore, suppression of tumor growth was evident in vivo.

CONCLUSION

Our results indicated that artesunate and allicin in combination exert synergistic effects on osteosarcoma cell proliferation and apoptosis.

The role and place of medicinal plants in the strategies for disease prevention

Medicinal plants have been used in healthcare since time immemorial. Studies have been carried out globally to verify their efficacy and some of the findings have led to the production of plant-based medicines. The global market value of medicinal plant products exceeds $100 billion per annum. This paper discusses the role, contributions and usefulness of medicinal plants in tackling the diseases of public health importance, with particular emphasis on the current strategic approaches to disease prevention. A comparison is drawn between the 'whole population' and 'high-risk' strategies. The usefulness of the common-factor approach as a method of engaging other health promoters in propagating the ideals of medicinal plants is highlighted. The place of medicinal plants in preventing common diseases is further examined under the five core principles of the Primary Health Care (PHC) approach. Medicinal plants play vital roles in disease prevention and their promotion and use fit into all existing prevention strategies. However, conscious efforts need to be made to properly identify, recognise and position medicinal plants in the design and implementation of these strategies. These approaches present interesting and emerging perspectives in the field of medicinal plants. Recommendations are proposed for strategising the future role and place for medicinal plants in disease prevention.