Immunomodulation of Zerumbone via Decreasing the Production of Reactive Oxygen Species from Immune Cells

Zerumbone-Loaded Nanostructured Lipid Carrier Gel Enhances Wound Healing in Diabetic Rats

This study investigated the healing effects of topical application of zerumbone, a well-known anti-inflammatory compounds loaded on nanostructured lipid carrier gel (Carbopol 940) (ZER-NLCG) on excisional wounds in streptozotocin-induced diabetic rats. Diabetic rats with inflicted superficial skin wound were topically treated with ZER-NLCG, empty NLCG, and silver sulfadiazine cream (SSDC) once daily for 21 days. Wound tissue samples were analyzed for proinflammatory cytokines, namely, interleukin-6 (IL-6), interleukin-1 β (IL-1β), and tumor necrosis factor-α (TNF-α), hydroxyproline contents, catalase, superoxide dismutase activities, and lipid peroxidation level, and were subjected to histopathological analysis, respectively. Among the treated groups, ZER-NLCG was the most effective at decreasing proinflammatory cytokine level and inflammatory cell infiltration while increasing antioxidant enzyme activities, hydroxyproline content, and granulation of wound tissues of diabetic rats. ZER-NLCG is a potent formulation for the enhancement of wound healing in diabetic rats through its anti-inflammatory, antioxidant, and tissue repair activities.

Evaluation of anti-methicillin-resistant Staphylococcus aureus property of zerumbone

CONTEXT AND OBJECTIVE

Zerumbone has been reported to exert anti-microbial effects, but the mechanism by which the compound exerts its action is not known. Thus, this study aimed to investigate the mechanism of action of zerumbone against methicillin-resistance Staphylococcus aureus (MRSA), using the atomic force microscopy (AFM), scanning electron microscopy (SEM), and flow cytometry techniques.

METHODS

MRSA (NCTC 13277) cell viability was determined using the microplate AlamarBlue assay. AFM and SEM were used to determine the morphology of zerumbone-treated MRSA cells. Flow cytometric analysis was used to determine the effect of zerumbone on bacterial membrane permeability and membrane potential, using the propidium iodide (PI) staining method, membrane potential-sensitive fluorescence probe, and DiBAC4(3) dye. DCFDA dye was used to determine the generation of reactive oxygen species (ROS) by MRSA.

RESULTS

Zerumbone significantly inhibited MRSA growth with a minimum inhibitory concentration (MIC) of 125 µg/ml. The AFM analysis showed that zerumbone caused leakage of cytoplasmic content from the bacterial cells. Ultrastructure analysis showed small colonies of the bacteria with pores on the membrane surface. There were increases in zerumbone-treated MRSA PI and DiBAC4(3) fluorescence, indicating an increase in cell membrane permeability and a decrease in membrane potential that culminated in the loss of membrane structural integrity and bacterial death. Based on DCFDA dye analysis, zerumbone also reduced ROS production by MRSA.

CONCLUSIONS

Zerumbone exerts anti-MRSA effects by causing membrane depolarization, increasing membrane permeability, and finally disrupting cell membrane and bacterial killing.

Ethyl acetate extract of Clausena excavata induces growth inhibition of non-small-lung cancer, NCI-H460, cell line via apoptosis

CONTEXT

Clausena excavata Burm. f is a plant used in folklore medicine for the treatment of various ailments in South East Asia. The plant parts contain chemical components that are cytotoxic to many cancer cells.

OBJECTIVE

The study investigated the cytotoxic effects of ethyl acetate, methanol and chloroform C. excavata leaf extracts on the non-small-lung cancer, NCI-H460, cell line.

METHODS

Based on the 3-(4,5-dimethylthiazol-2-yl)-2,5,-diphenyltetrazolium bromide (MTT) assay, among extracts, ethyl acetate C. excavata leaf extract (EACE) was the most potent anti-NCI-H460 cells, with IC50 value of 47.1 ± 6.1 μg/ml. The effects of EACE on NCI-H460 cells were also determined by clonogenic, 4', 6-diamidino-2-phenylindole (DAPI), and annexin-V-fluorescein isothiocyanate/propidium iodide-PI flow cytometric assays. Reactive oxygen species (ROS) production and apoptotic gene expressions was determined via flow cytometry and real-time quantitative PCR, respectively.

RESULTS

EACE-treated NCI-H460 cells after 48 h underwent apoptosis as evident by loss of cell viability, cell shrinkage, and chromatin condensation. The results also showed EACE mediated increase in ROS production by the NCI-H460 cells. After 48 h treatment, EACE increased the pro-apoptotic BAX and decreased the anti-apoptotic Bcl-2, Survivin and c-Myc gene expressions.

CONCLUSIONS

EACE is a potential anti-lung cancer by increasing cancer cell ROS production and apoptosis.

Anti-Enterococcus Faecalis, Cytotoxicity, Phytotoxicity, and Anticancer Studies on Clausena excavata Burum. f. (Rutaceae) Leaves

BACKGROUND

Clausena excavata Burum. f. has long been applied in ethnomedicine for the treatment of various disorders like rhinitis, headache, cough, wound healing, fever, and detoxification. This study is aimed at investigating the antibacterial activity against Enterococcus faecalis ATCC 49532 using AlamarBlue assay and atomic force microscopy (AFM) as well as the cytotoxicity, anticancer, and phytotoxicity of C. excavata.

METHOD

Bacterial cell viability was performed by using microplate AlamarBlue assay. Atomic force microscopy was used to determine morphological changes in the surface of bacterial cells. Cytotoxicity and phytotoxicity were determined by brine shrimp lethality and Lemna minor bioassay. Caco-2 (colorectal adenocarcinoma) cell line was used for the evaluation of the anticancer effects.

RESULT

Among the fractions tested, ethyl acetate (EA) fraction was found to be active with minimum inhibitory concentration (MIC) of 750 μg/mL against E. faecalis, but other fractions were found to be insensitive to bacterial growth. Microscopically, the EA fraction-treated bacteria showed highly damaged cells with their cytoplasmic content scattered all over. The LC50 value of the EA fraction against brine shrimp was more than 1000 μg/mL showing the nontoxic nature of this fraction. Chloroform (CH), EA, and methanol (MOH) fractions of C. excavata were highly herbicidal at the concentration of 1000 μg/mL. EA inhibited Caco-2 cell line with an IC50 of 20 μg/mL.

CONCLUSIONS

This study is the first to reveal anti-E. faecalis property of EA fraction of C. excavata leaves, natural herbicidal, and anticancer agents thus highlight the potential compound present in its leaf which needs to be isolated and tested against multidrug-resistant E. faecalis.

Modulation of the tumor microenvironment by natural agents: implications for cancer prevention and therapy

The development of cancer is not just the growth and proliferation of a single transformed cell, but its surrounding environment also coevolves with it. Indeed, successful cancer progression depends on the ability of the tumor cells to develop a supportive tumor microenvironment consisting of various types of stromal cells. The interactions between the tumor and stromal cells are bidirectional and mediated through a variety of growth factors, cytokines, metabolites, and other biomolecules secreted by these cells. Tumor-stromal crosstalk creates optimal conditions for the tumor growth, metastasis, evasion of immune surveillance, and therapy resistance, and its targeting is being explored for clinical management of cancer. Natural agents from plants and marine life have been at the forefront of traditional medicine. Numerous epidemiological studies have reported the health benefits imparted on the consumption of certain fruits, vegetables, and their derived products. Indeed, a significant majority of anti-cancer drugs in clinical use are either naturally occurring compounds or their derivatives. In this review, we describe fundamental cellular and non-cellular components of the tumor microenvironment and discuss the significance of natural compounds in their targeting. Existing literature provides hope that novel prevention and therapeutic approaches will emerge from ongoing scientific efforts leading to the reduced tumor burden and improve clinical outcomes in cancer patients.

Zerumbone Protects against Carbon Tetrachloride (CCl4)-Induced Acute Liver Injury in Mice via Inhibiting Oxidative Stress and the Inflammatory Response: Involving the TLR4/NF-κB/COX-2 Pathway

The natural compound Zerumbone (hereinafter referred to as ZER), a monocyclic sesquiterpenoid, has been reported to possess many pharmacological properties, including antioxidant and anti-inflammatory properties. This study aimed to investigate the underlying mechanism of ZER against acute liver injury (ALI) in CCl₄-induced mice models. ICR mice were pretreated intraperitoneally with ZER for five days, then received a CCl₄ injection two hours after the last ZER administration and were sacrificed 24 h later. Examination of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities and the histopathological analysis confirmed the hepatoprotective effect of ZER. Biochemical assays revealed that ZER pretreatment recovered the activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), restored the glutathione (GSH) reservoir, and reduced the production of malondialdehyde (MDA), all in a dose-dependent manner. Furthermore, administration of ZER in vivo reduced the release amounts of pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) and inhibited the increased protein levels of Toll-like receptor 4 (TLR4), nuclear factor-kappaB (NF-κB) p-p65, and cyclooxygenase (COX-2). Further studies in lipopolysaccharide (LPS)-induced Raw264.7 inflammatory cellular models verified that ZER could inhibit inflammation via inactivating the TLR4/NF-κB/COX-2 pathway. Thus, our study indicated that ZER exhibited a hepatoprotective effect against ALI through its antioxidant and anti-inflammatory activities and the possible mechanism might be mediated by the TLR4/NF-κB/COX-2 pathway. Collectively, our studies indicate ZER could be a potential candidate for chemical liver injury treatment.