6-Gingerol alleviates ectopic lipid deposition in skeletal muscle by regulating CD36 translocation and mitochondrial function

Ectopic lipid deposition (ELD) and mitochondrial dysfunction are common causes of metabolic disorders in humans. Consuming too much fructose can result in mitochondrial dysfunction and metabolic disorders. 6-Gingerol, the main component of ginger (Zingiber officinale Roscoe), has been proven to alleviate metabolic disorders. This study seeks to examine the effects of 6-gingerol on metabolic disorders caused by fructose and uncover the underlying molecular mechanisms. In this study, the results showed that 6-Gingerol ameliorated high-fructose-induced metabolic disorders. Moreover, it inhibited CD36 membrane translocation, increased CD36 expression in the mitochondria, and decreased the O-GlcNAc modification of CD36 and OGT expression in vitro and vivo. In addition, 6-Gingerol enhanced the performance of mitochondria in the skeletal muscle and boosted the respiratory capability of L6 myotubes. This study provides a theoretical basis and new insights for the development of lipid-lowering drugs in clinical practice.

Assessing the antibacterial potential of 6-gingerol: Combined experimental and computational approaches

The rise of antibiotic resistance in bacteria is becoming a global concern, particularly due to the dwindling supply of new antibiotics. This situation mandates the discovery of new antimicrobial candidates. Plant-derived natural compounds have historically played a crucial role in the development of antibiotics, serving as a rich source of substances possessing antimicrobial properties. Numerous studies have supported the reputation of 6-gingerol, a prominent compound found in the ginger family, for its antibacterial properties. In this study, the antibacterial activities of 6-gingerol were evaluated against Gram-negative bacteria, Acinetobacter baumannii and Klebsiella pneumoniae, with a particular focus on the clinically significant Gram-negative Pseudomonas aeruginosa and Gram-positive bacteria Staphylococcus aureus. Furthermore, the anti-virulence activities were assessed in vitro, in vivo, and in silico. The current findings showed that 6-gingerol's antibacterial activity is due to its significant effect on the disruption of the bacterial cell membrane and efflux pumps, as it significantly decreased the efflux and disrupted the cell membrane of S. aureus and P. aeruginosa. Furthermore, 6-gingerol significantly decreased the biofilm formation and production of virulence factors in S. aureus and P. aeruginosa in concentrations below MICs. The anti-virulence properties of 6-gingerol could be attributed to its capacity to disrupt bacterial virulence-regulating systems; quorum sensing (QS). 6-Gingerol was found to interact with QS receptors and downregulate the genes responsible for QS. In addition, molecular docking, and molecular dynamics (MD) simulation results indicated that 6-gingerol showed a comparable binding affinity to the co-crystalized ligands of different P. aeruginosa QS targets as well as stable interactions during 100 ns MD simulations. These findings suggest that 6-gingerol holds promise as an anti-virulence agent that can be combined with antibiotics for the treatment of severe infections.

6-Gingerol attenuates hepatic ischemia/reperfusion injury through regulating MKP5-mediated P38/JNK pathway

6-Gingerol, the main bioactive compound of ginger, has antioxidant, anti-inflammatory, anti-cancer and neuroprotective effects. However, it is unclear whether 6-Gingerol has protective effects against hepatic ischemia/reperfusion (I/R) injury. In this study, the mouse liver I/R injury model and the mouse AML12 cell hypoxia/reoxygenation (H/R) model were established by pretreatment with 6-Gingerol at different concentrations to explore the potential effects of 6-Gingerol. Serum transaminase levels, liver necrotic area, cell viability, inflammatory response, and cell apoptosis were used to assess the effect of 6-Gingerol on hepatic I/R or cell H/R injury. Quantitative polymerase chain reaction (qPCR) and Western blotting were used to detect the mRNA and protein expression. The results show that 6-Gingerol decreased serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels, liver necrosis, inflammatory cytokines IL-1β, IL-6, MCP-1, TNF-α expression, Ly6g+ inflammatory cell infiltration, protein phosphorylation of NF-κB signaling pathway, Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) positive cells, cell apoptosis rate, the protein expression of pro-apoptotic protein BAX and C-Caspase3, increased cell viability, and expression of anti-apoptotic protein BCL-2. Moreover, 6-Gingerol could increase the mRNA and protein expression of mitogen activated protein kinase phosphatase 5 (MKP5) and inhibit the activation of P38/JNK signaling pathway. In MKP5 knockout (KO) mice, the protective effect of 6-gingerol and the inhibition of P38/JNK pathway were significantly weakened. Therefore, our results suggest that 6-Gingerol exerts anti-inflammatory and anti-apoptotic effects to attenuate hepatic I/R injury by regulating the MKP5-mediated P38/JNK signaling pathway.

Natural compounds proposed for the management of non-alcoholic fatty liver disease

Although non-alcoholic fatty liver disease (NAFLD) presents as an intricate condition characterized by a growing prevalence, the often-recommended lifestyle interventions mostly lack high-level evidence of efficacy and there are currently no effective drugs proposed for this indication. The present review delves into NAFLD pathology, its diverse underlying physiopathological mechanisms and the available in vitro, in vivo, and clinical evidence regarding the use of natural compounds for its management, through three pivotal targets (oxidative stress, cellular inflammation, and insulin resistance). The promising perspectives that natural compounds offer for NAFLD management underscore the need for additional clinical and lifestyle intervention trials. Encouraging further research will contribute to establishing more robust evidence and practical recommendations tailored to patients with varying NAFLD grades.

Mercury chloride causes cognitive impairment, oxidative stress and neuroinflammation in male Wistar rats: The potential protective effect of 6-gingerol-rich fraction of Zingiber officinale via regulation of antioxidant defence system and reversal of pro-inflammatory markers increase

This study investigated the effects of 6-gingerol-rich fraction of Zingiber officinale (6-GIRIFZO) on mercury chloride (HgCl2)-induced neurotoxicity in Wistar rats. Thirty -five male Wistar rats weighing between (150-200 g) were divided randomly into five groups (n = 7): group 1: control, received 0.5 mL of normal saline, group 2: received HgCl2 (5 mg/kg), group 3: received N-acetylcysteine (NAC) (50 mg/kg) as well as HgCl2 (5 mg/kg), group 4: received 6-GIRIFZO (100 mg/kg) and HgCl2 (5 mg/kg), group 5: had 6-GIRIFZO (200 mg/kg) and HgCl2 (5 mg/kg), consecutively for 14 days. On the day14, the rats were subjected to behavioural tests using a Morris water maze and novel object recognition tests. The rats were then euthanized to obtain brain samples for the determination of biochemical parameters (acetylcholinesterase (AchE), nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione (GSH), tumor necrosis factor- alpha (TNF-α), nuclear factor kappa-B (NF-κB), interleukin-1β (IL-1β) and interleukin-6 (IL-6)) using standard methods. The result revealed a significant increase in escape latency and a significant decrease in recognition ratio in the rats that were exposed to HgCl2 only. However, 6-GIRIFZO produced a significant reduction in the escape latency and (p < 0.05) increase in the recognition ratio. Similarly, HgCl2 exposure caused a significant (p < 0.05) decrease in the brain SOD, GPx, CAT, GSH with increased brain levels of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Similarly to the standard drug, NAC, 6-GIRIFZO (100 and 200 mg/kg) significantly (p < 0.05) increased brain SOD, GPx, CAT, and GSH levels with decreased concentrations of MDA, NO, AchE, TNF-α, NF-κB, IL-1β and IL-6. Also, pre-treatment with 6-GIRIFZO prevented the HgCl2-induced morphological aberrations in the rats. This study concludes that 6-GIRIFZO prevents HgCl2-induced cognitive deficit via reduction of brain inflammation as well as oxidative stress in rats.

Screening of Active Substances Regulating Alzheimer's Disease in Ginger and Visualization of the Effectiveness on 6-Gingerol Pathway Targets

Ginger has been reported to potentially treat Alzheimer's disease (AD), but the specific compounds responsible for this biological function and their mechanisms are still unknown. In this study, a combination of network pharmacology, molecular docking, and dynamic simulation technology was used to screen active substances that regulate AD and explore their mechanisms. The TCMSP, GeneCards, OMIM, and DisGeNET databases were utilized to obtain 95 cross-targets related to ginger's active ingredients and AD as key targets. A functional enrichment analysis revealed that the pathways in which ginger's active substances may be involved in regulating AD include response to exogenous stimuli, response to oxidative stress, response to toxic substances, and lipid metabolism, among others. Furthermore, a drug-active ingredient-key target interaction network diagram was constructed, highlighting that 6-Gingerol is associated with 16 key targets. Additionally, a protein-protein interaction (PPI) network was mapped for the key targets, and HUB genes (ALB, ACTB, GAPDH, CASP3, and CAT) were identified. Based on the results of network pharmacology and cell experiments, 6-Gingerol was selected as the active ingredient for further investigation. Molecular docking was performed between 6-Gingerol and its 16 key targets, and the top three proteins with the strongest binding affinities (ACHE, MMP2, and PTGS2) were chosen for molecular dynamics analysis together with the CASP3 protein as the HUB gene. The findings indicate that 6-Gingerol exhibits strong binding ability to these disease targets, suggesting its potential role in regulating AD at the molecular level, as well as in abnormal cholinesterase metabolism and cell apoptosis, among other related regulatory pathways. These results provide a solid theoretical foundation for future in vitro experiments using actual cells and animal experiments to further investigate the application of 6-Gingerol.

6-Gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition in LPS-provoked ARDS via RUNX1/NF-κB signaling pathway

BACKGROUND

Alveolar hypercoagulation and fibrinolytic inhibition play a central role in refractory hypoxemia in acute respiratory distress syndrome (ARDS), but it lacks effective drugs for prevention and treatment of this pathophysiology. Our previous experiment confirmed that RUNX1 promoted alveolar hypercoagulation and fibrinolytic inhibition through NF-κB pathway. Other studies demonstrated that 6-gingerol regulated inflammation and metabolism by inhibiting the NF-κB signaling pathway. We assume that 6-gingerol would ameliorate alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/ NF-κB pathway in LPS-induced ARDS.

METHODS

Rat ARDS model was replicated through LPS inhalation. Before LPS inhalation, the rats were intraperitoneally treated with different doses of 6-gingerol or the same volume of normal saline (NS) for 12 h, and then intratracheal inhalation of LPS for 24 h. In cell experiment, alveolar epithelial cell type II (AECII) was treated with 6-gingerol for 6 h and then with LPS for another 24 h. RUNX1 gene was down-regulated both in pulmonary tissue and in cells. Tissue factor (TF), plasminogen Activator Inhibitor 1(PAI-1) and thrombin were determined by Wester-blot (WB), qPCR or by enzyme-linked immunosorbent (ELISA). Lung injury score, pulmonary edema and pulmonary collagen III in rat were assessed. NF-κB pathway were also observed in vivo and in vitro. The direct binding capability of 6-gingerol to RUNX1 was confirmed by using Drug Affinity Responsive Target Stability test (DARTS).

RESULTS

6-gingerol dose-dependently attenuated LPS-induced lung injury and pulmonary edema. LPS administration caused excessive TF and PAI-1 expression both in pulmonary tissue and in AECII cell and a large amount of TF, PAI-1 and thrombin in bronchial alveolar lavage fluid (BALF), which all were effectively decreased by 6-gingerol treatment in a dose-dependent manner. The high collagen Ⅲ level in lung tissue provoked by LPS was significantly abated by 6-gingerol. 6-gingerol was seen to dramatically inhibit the LPS-stimulated activation of NF-κB pathway, indicated by decreases of p-p65/total p65, p-IKKβ/total IKKβ, and also to suppress the RUNX1 expression. RUNX1 gene knock down or RUNX1 inhibitor Ro5-3335 significantly enhanced the efficacies of 6-gingerol in vivo and in vitro, but RUNX1 over expression remarkably impaired the effects of 6-gingerol on TF, PAI-1 and on NF-κB pathway. DARTS result showed that 6-gingerol directly bond to RUNX1 molecules.

CONCLUSIONS

Our experimental data demonstrated that 6-gingerol ameliorates alveolar hypercoagulation and fibrinolytic inhibition via RUNX1/NF-κB pathway in LPS-induced ARDS. 6-gingerol is expected to be an effective drug in ARDS.

Effect of microwave-assisted drying and extraction of 6-Shogaol from Zingiber officinale Roscoe

Ginger (Zingiber officinale Roscoe, Zingeberaceae) is a medicinal plant widely used as food, spice, or flavoring agent worldwide. 6-Shogaol is a compound of prime interest in exhibiting anti-inflammatory, antioxidant and chemopreventive effects. The objective of the study is to investigate the effect of microwave-assisted drying (MAD) followed by microwave-assisted extraction (MAE) so as to produce 6-Shogaol enriched Ginger with improved therapeutic benefits. Various drying techniques viz. shade drying, tray drying, microwave-assisted drying and osmotic dehydration as a pretreatment were used for drying Ginger rhizomes. The dried rhizomes were extracted by conventional solvent extraction and microwave-assisted extraction techniques and tested for content of 6-Shogaol using the newly developed HPLC method whereas total flavonoid and polyphenol content were determined using the UV spectrophotometric method. Subjecting the microwave dried Ginger to microwave-assisted extraction for 45 min at constant power level of 284 W resulted in a significant rise in the extractability of 6-Shogaol (1.660 ± 0.018), total polyphenols (855.46 ± 5.33) and flavonoids (617.97 ± 6.40) compared to the conventional method of extraction. The proposed Ginger processing method of microwave drying followed by microwave extraction outperforms traditional methods in terms of speed, convenience, and performance thus can be scaled up to industrial levels.

Structure based docking and biological evaluation towards exploring potential anti-cancerous and apoptotic activity of 6-Gingerol against human prostate carcinoma cells

BACKGROUND

6-Gingerol (6-G) is the primary active phytocomponent of ginger and has been shown to regulate multiple targets against cancer and its treatment. Androgen receptors (ARs) remain critical in the progression of prostate cancer (PCa). This study focuses on investigating 6-G as a promising anti-cancerous agent that inhibits AR activity significantly.

METHODS

In this study, molecular docking simulation was done to investigate the binding affinity of 6-G and control drug Bicalutamide (BT) against oncogenic AR and tumor suppressor estrogen receptor β (ERβ). The crystal structure of AR and ERβ was retrieved from Protein Data Bank (PDB) and docked with 3D Pubchem structures of 6-G using iGEMDOCK and AutoDock. Further in vitro study was done to evaluate the antioxidant, anti-cancerous, apoptotic, and wound healing potential of 6-G.

RESULTS

The result displays that 6-G shows good binding affinity with AR and ERβ. Condensation of the nucleus, change in mitochondrial membrane potential (MMP) and the ability to induce reactive oxygen species (ROS) were done in human PCa PC-3 cells. Results from the MTT assay demonstrated that 6-G and control drug BT showed significant (p < 0.01) dose and time dependent inhibition of human PCa PC-3 cells. 6-G increased the ROS generation intracellularly and decreased the MMP, and cell migration in treated PCa PC-3 cells. 6-G treated cells showed fragmented, condensed chromatin and nuclear apoptotic bodies.

CONCLUSIONS

Thus, this study validates 6-G as a potential drug candidate against human PCa. However, further study of the anticancer potency of 6-G has to be done before its use for PCa treatment.

6-Gingerol regulates triglyceride and cholesterol biosynthesis to improve hepatic steatosis in MAFLD by activating the AMPK-SREBPs signaling pathway

Excessive synthesis of triglycerides and cholesterol accelerates the progression of hepatic steatosis in metabolic-associated fatty liver disease (MAFLD). However, the precise mechanism by which 6-gingerol mitigates hepatic steatosis in MAFLD model mice has yet to be fully understood. The present study observed that 6-gingerol administration exhibited significant protective effects against obesity, insulin resistance, and hepatic steatosis in mice subjected to a high-fat diet (HFD), and mitigated lipid accumulation in HepG2 cells treated with palmitate (PA). Following the hepatic lipidomic analysis, we confirmed that the AMPK-SREBPs signaling pathway as the underlying molecular mechanism by which 6-gingerol inhibited triglyceride and cholesterol biosynthesis, both in vivo and in vitro, through Western blot and immunofluorescence assay. Additionally, the application of an AMPK agonist/inhibitor further validated that 6-gingerol promoted AMPK activation by increasing the phosphorylation level of AMPK in vitro. Notably, the inhibitory effect of 6-gingerol on cholesterol biosynthesis, rather than triglyceride biosynthesis, was significantly diminished after silencing SREBP2 using a lentiviral plasmid shRNA in HepG2 cells. Our study demonstrates that 6-gingerol mitigates hepatic triglyceride and cholesterol biosynthesis to alleviate hepatic steatosis by activating the AMPK-SREBPs signaling pathway, indicating that 6-gingerol may be a potential candidate in the therapy of MAFLD.

6-Gingerol via overexpression of miR-322-5p impede lipopolysaccharide-caused inflammatory response in RAW264.7 cells

Acute lung injury (ALI) and sepsis are complicated syndromes that are often left untreated in critically ill patients. 6-Gingerol is a phenolic phytochemical compound that is found in fresh ginger, has pharmacological effects against inflammation. This study explored the roles of 6-gingerol in a mouse model of acute lung injury caused by lipopolysaccharide (LPS) and RAW-264.7 cells inflammation. The LPS-induced animal model underwent histopathological examinations, and RAW-264.7 cells viability was determined by Cell counting Kit-8 (CCk-8) assay. Additionally, qRT-PCR, Immunofluorescence, Western blot, and ELISA were used in vivo and in vitro to identify inflammatory factors and proteins associated with NF-κB and MAPK signaling pathways. In a histological examination 6-gingerol exhibited protective effects. Moreover, 6-gingerol elevated cell viability and downregulated inflammatory factors Interlukin-1β (IL-1β), Interlukin-6 (IL-6) and Tumor necrosis factor-α (TNF-α) in LPS-treated RAW-264.7 cells. Furthermore, 6-gingerol decreased phosphorylation of P65, P38 and the level of JNK in NF-κB and MAPK pathways. Importantly, 6-gingerol increased transcript abundance of miR-322-5p which suppressed by LPS and miR-322-5p downregulation negated the protective functions of 6-gingerol. The protective activity of 6-gingerol was mediated by miR-322-5p up-regulation.

Mechanism exploration of 6-Gingerol in the treatment of atherosclerosis based on network pharmacology, molecular docking and experimental validation

BACKGROUND

The 6-Gingerol has significant anti-inflammatory, anti-oxidative and hypolipidemic activities and is widely used for treating cardiac-cerebral vascular diseases. However, the multi-target mechanism of 6-Gingerol in the treatment of atherosclerosis remains to be elucidated.

METHODS

Firstly, the therapeutic actions of 6-Gingerol anti-atherosclerosis were researched based on an atherosclerotic ApoE-deficient mice model induced by high-fat feed. Then, network pharmacology and molecular docking were employed to reveal the anti-atherogenic mechanism of 6-Gingerol. Finally, the target for these predictions was validated by target protein expression assay in vitro and in vivo experiments and further correlation analysis.

RESULTS

Firstly, 6-Gingerol possessed obvious anti-atherogenic activity, which was manifested by a significant reduction in the plaque area, decrease in the atherosclerosis index and vulnerability index. Secondly, based on network pharmacology, 14 predicted intersection target genes between the targets of 6-Gingerol and atherogenic-related targets were identified. The key core targets of 6-Gingerol anti-atherosclerosis were found to be TP53, RELA, BAX, BCL2, and CASP3. Lipid and atherosclerosis pathways might play a critical role in 6-Gingerol anti-atherosclerosis. Molecular docking results also further revealed that the 6-Gingerol bound well and stable to key core targets from network pharmacological predictions. Then, the experimental results in vivo and in vitro verified that the up-regulation of TP53, RELA, BAX, CASP3, and down-regulation of BCL2 from atherosclerotic ApoE-deficient mice model can be improved by 6-Gingerol intervention. Meanwhile, the correlation analysis further confirmed that 6-Gingerol anti-atherosclerosis was closely related to these targets.

CONCLUSION

The 6-Gingerol can markedly improve atherosclerosis by modulating key multi-targets TP53, RELA, BAX, CASP3, and BCL2 in lipid and atherosclerosis pathways. These novel findings shed light on the anti-atherosclerosis mechanism of 6-Gingerol from the perspective of multiple targets and pathways.

6-Gingerol attenuates sepsis-induced acute lung injury by suppressing NLRP3 inflammasome through Nrf2 activation

INTRODUCTION

Sepsis is characterized by an inappropriate inflammatory response. Acute lung injury (ALI) is the most common type of organ injury in sepsis, with high morbidity and mortality. 6-Gingerol is the main bioactive compound of ginger, and it possesses anti-inflammatory bioactivity in different diseases. This study is aimed to explore the specific function of 6-Gingerol in sepsis-induced ALI.

MATERIAL AND METHODS

Lipopolysaccharide (LPS) was intraperitoneally injected into Sprague-Dawley rats for establishing the ALI models in vivo. The ALI rats were intraperitoneally injected with 20 mg/kg 6-Gingerol. The contents of oxidative stress markers malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) were detected in the lung tissues of ALI rats. The concentrations of inflammatory factors [Tumor Necrosis Factor alpha (TNF-α), interleukin (IL)-6, and IL-1β] were measured by ELISA. Inflammatory cell infiltration in bronchoalveolar lavage fluid (BALF) of rats was tested. Western blot was utilized to test the protein levels of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1) in lung tissues. Furthermore, immunohistochemical staining was applied for testing the expression of NLRP3 inflammasome in lung tissues.

RESULTS

The pathological changes in ALI rats were characterized by increased accumulation of inflammatory cells, alveolar hemorrhage, and pulmonary interstitial edema. However, the degree of pathological injury of lung tissues was significantly improved after 6-Gingerol treatment. Additionally, 6-Gingerol significantly attenuated the lung wet/dry ratio and protein permeability index (PPI) of LPS-induced rats. Furthermore, 6-Gingerol repressed oxidative stress and inflammatory reaction in LPS-induced rats by reducing the contents of MDA, GSH, SOD, TNF-α, IL-6, and IL-1β in the lung. LPS-induced infiltration of eosinophils, macrophages, neutrophils, and lymphocytes into lung was suppressed by 6-Gingerol administration. Moreover, 6-Gingerol activated Nrf2/HO-1 signaling and repressed LPS-induced‑NLRP3 inflammasome expression in lung tissues of LPS-induced rats. Intraperitoneal injection of ML385 (Nrf2 inhibitor) treatment into rats reversed the effects of 6-Gingerol on lung injury, inflammation, and oxidative stress in LPS-subjected rats.

CONCLUSIONS

6-Gingerol attenuates sepsis-induced ALI by suppressing NLRP3 inflammasome activation through Nrf2 activation.

Ethnomedicinal uses of Indian spices used for cancer treatment: A treatise on structure-activity relationship and signaling pathways

Cancer is among the major cause of demise worldwide. Though the array of anticancer chemical medications is available but unfortunately, they are also associated with negative health effects. The invaluable therapeutic potential of spices makes them an integral part of our daily diet. Therefore, the present work focuses on the traditional uses of 46 spices and the phytochemical analysis of 31 spices. Out of them, only 29 spices are explored for their cytotoxicity against different cancer cell lines. The pre-clinical and clinical anticancer studies of spices along with their toxicity, mechanism of actions like Wnt/β-catenin, phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), JAK/STAT, mitogen-activated protein kinase (MAPK), Notch-mediated pathways and Quantitative structure-activity relationship (QSAR) studies were also focused. Curcumin was found as one of the most explored bioactive in every aspect such as in-vitro, in-vivo, clinical as well as SAR anticancer studies while some other bioactive such as 1,8-Cineole, trans-Anethole, Diosgenin, Trigonelline are either unexplored or least explored for their clinical and SAR studies. In fact, traditional medicinal uses of spices also provide solid shreds of evidence for the new leads towards the invention of novel anticancer agents. Therefore, further research can be designed for the anticancer marketed formulation from spices after having their placebo and related toxicological data.

Development of Optimized Novel Liposome Loaded with 6-gingerol and Assessment of its Therapeutic Activity Against NSCLC In vitro and In vivo Experimental Models

6-Gingerol (Gn) is an active compound derived from ginger which possesses various biological activities. The therapeutic applications of Gn are limited due to its hydrophobic nature. To ease its administration, one of the nano-emulsion methods, liposome was selected to encapsulate Gn. Response Surface Methodology (RSM) was used to optimize liposome ratio. 97.2% entrapment efficiency was achieved at the ratio of 1:20:2 (Drug: Lipid: Cholesterol). The optimized liposome attained size below 200 d nm, spherical shape, negative surface charge and showed sustain release upon physical characterization methods such as FESEM, DLS, Zeta potential, Drug release. The signature FTIR peaks of both free Gn and free liposome (FL) were also observed in Lipo-Gn peak. Lipo-Gn showed significant cytotoxic effect on A549 cells (IC50 160.5 ± 0.74µM/ml) as well as inhibits the cell migration. DAPI staining showed higher apoptotic nuclear morphological change in the cells treated with Lipo-Gn, and also Lipo-Gn increased the apoptotic percentage in A549 as 39.89 and 70.32 for 12 and 24h respectively which were significantly more than free Gn. Moreover, the formulation of Lipo-Gn showed significant cell cycle arrest at the G2/M phase compared with free Gn (28.9 and 34.9% in Free Gn vs. 42.7 and 50.1% in Lipo -Gn for 12 and 24hours respectively). Lipo-Gn have been assessed in NSCLC induced BALB/c mice and showed significantly improved pharmacological properties compared to those of free Gn. Thus, Lipo-Gn may be considered for its widening applications against lung cancer.

6-Gingerol exerts a protective effect against hypoxic injury through the p38/Nrf2/HO-1 and p38/NF-κB pathway in H9c2 cells

Ginger, one of the most widely consumed condiment for various foods and beverages, has many pharmacological effects. 6-gingerol, a naturally occurring phenol, is one of the major pungent constituents of ginger. The purpose of this study was to characterize the effect of 6-gingerol on the p38/Nrf2/HO-1 and p38/NF-κB signaling pathway, as a possible means of combating hypoxia-related oxidative stress. H9c2 cells were chemically induced with CoCl₂ to mimic hypoxia-associated cellular damage. Cardiomyocyte injury was assessed by lactate dehydrogenase and creatine kinase. Reactive oxygen species production was assessed by 2',7'-dichlorodihydrofluorescein diacetate. The antioxidative property of 6-gingerol was measured by estimating the activities of superoxide dismutase, catalase, glutathione and glutathione disulfide. Apoptosis was detected by flow cytometry after Annexin V-FITC-propidium iodide double staining. Western blotting was used to evaluate levels of p-p38, p38, cytoplasm p65, nuclear p65, total p65, nuclear Nrf2, total Nrf2, Keap1, HIF-1α, and HO-1. 6-gingerol was able to counter hypoxia-induced cardiomyocyte injury as evidenced by inhibiting the levels of oxidative stress indexes and increasing the percentage of apoptosis. Furthermore, 6-gingerol was able to down-regulate p-p38/p38, nuclear p65, total p65 and Keap1 expression induced by CoCl₂ stimulation and increased cytoplasm p65, nuclear Nrf2, total Nrf2, HO-1, and HIF-1α expression. However, treatment with specific Nrf2 inhibitor blunted the activation of Nrf2 signaling and removed the protective effects of 6-gingerol. These experiments provide evidence that 6-gingerol exerts cytoprotective effects, which may be associated with the regulation of oxidative stress and apoptosis, potentially through activating the Nrf2 pathway and inhibiting the p38/NF-κB pathways.

In vitro and in vivo therapeutic potentials of 6-gingerol in combination with amphotericin B for treatment of Leishmania major infection: Powerful synergistic and multifunctional effects

The ongoing conventional drugs for leishmaniasis treatment are insufficient. The present study aimed to assess 6-gingerol alone and in combination with amphotericin B on Leishmania major stages using experimental and in vivo murine models. Here, arrays of experimental approaches were designed to monitor and evaluate the 6-gingerol potential therapeutic outcomes. The binding affinity of 6-gingerol and IFN-γ was the basis for docking conformations. 6-Gingerol combined with amphotericin B represented a safe mixture, extremely leishmanicidal, a potent antioxidant, induced a remarkable apoptotic index, significantly increased the expression of the Th1-related cytokines (IL-12p40, IFN-γ, and TNF- α), iNOS, and transcription factors (STAT1, c-Fos, and Elk-1). In contrast, the expression of the Th2-related cytokines was significantly downregulated (p < 0.001). This combination was also potent when the lesion appearance was evaluated following three weeks of treatment. The histopathological and immunohistochemical patterns of the murine model represented clusters of CD4+ and CD8+ T lymphocytes which compressed and deteriorated the macrophages harboring Leishman bodies. The primary mode of action of 6-gingerol and amphotericin B involved broad mechanistic insights providing a coherent basis for further clinical study as a potential drug candidate for CL. In conclusion, 6-gingerol with amphotericin B synergistically exerted anti-leishmanial activity in vitro and in vivo and potentiated macrophages' leishmanicidal activity, modulated Th1- and Th2-related phenotypes improved the histopathological changes in the BALB/c mice infected with L. major. They elevated the leukocyte infiltration into the lesions. Therefore, this combination should be considered for treating volunteer patients with CL in clinical studies.

6-Gingerol protects against cerebral ischemia/reperfusion injury by inhibiting NLRP3 inflammasome and apoptosis via TRPV1 / FAF1 complex dissociation-mediated autophagy

BACKGROUND

Our previous studies demonstrated that autophagy alleviates cerebral I/R injury by inhibiting NLRP3 inflammasome-mediated inflammation. 6-Gingerol, a phenolic compound extracted from ginger, was reported to possess potent antiapoptotic and anti-inflammatory activities and is associated with autophagy. However, the effects of 6-Gingerol in cerebral I/R injury have not been elucidated, and whether they involve autophagy-induced NLRP3 inflammasome inhibition remains unclear.

METHODS

Adult male Sprague-Dawley (SD) rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h, followed by reperfusion for 24 h. 6-Gingerol and 3-methyladenine (3-MA) were injected intraperitoneally, and si-TRPV1 was injected via the lateral ventricle. Cerebral infarct volume, brain edema, neurological deficits, HE and Nissl were used to evaluate the morphological and functional changes of brain tissue, respectively. TRPV1, FAF1, autophagy related (LC3II/I, P62, Beclin1), inflammation related (NLRP3, cleaved-caspase-1, caspase-1, cleaved-IL-1β, IL-1β, cleaved-IL-18, IL-18) and apoptosis related (Bcl-2, Bax, cleaved-caspase-3) proteins were assessed by Western blot, immunofluorescence staining and coimmunoprecipitation, respectively. Enzyme linked immunosorbent assay (ELISA) was used to evaluate the changes in the expression levels of interleukin-1 (IL-1β) and interleukin-18(IL-18), respectively. The degree of neuronal apoptosis was evaluated by TUNEL staining. Neuronal ultrastructure was examined by transmission electron microscopy.

RESULT

6-Gingerol treatment significantly reduced cerebral infarct volume, improved brain edema and neurological scores, and reversed brain histomorphological damage after I/R injury. In addition, 6-Gingerol significantly reduced NLRP3 inflammasome-derived inflammation and neuronal apoptosis and upregulated autophagy. The autophagy inhibitor 3-MA rescued the effects of 6-Gingerol on the NLRP3 inflammasome and apoptosis. Moreover, the findings illustrated that 6-Gingerol inhibited autophagy-induced NLRP3 inflammasome activation and apoptosis through the dissociation of TRPV1 from FAF1.

CONCLUSION

In brief, 6-Gingerol exerts antiapoptotic and anti-inflammatory effects via TRPV1/FAF1 complex dissociation-mediated autophagy during cerebral I/R injury. Therefore, 6-Gingerol may be an effective drug for the treatment of I/R injury.

Potential Antitumor Effects of 6-Gingerol in p53-Dependent Mitochondrial Apoptosis and Inhibition of Tumor Sphere Formation in Breast Cancer Cells

Hormone-specific anticancer drugs for breast cancer treatment can cause serious side effects. Thus, treatment with natural compounds has been considered a better approach as this minimizes side effects and has multiple targets. 6-Gingerol is an active polyphenol in ginger with various modalities, including anticancer activity, although its mechanism of action remains unknown. Increases in the level of reactive oxygen species (ROS) can lead to DNA damage and the induction of DNA damage response (DDR) mechanism, leading to cell cycle arrest apoptosis and tumorsphere suppression. Epidermal growth factor receptor (EGFR) promotes tumor growth by stimulating signaling of downstream targets that in turn activates tumor protein 53 (p53) to promote apoptosis. Here we assessed the effect of 6-gingerol treatment on MDA-MB-231 and MCF-7 breast cancer cell lines. 6-Gingerol induced cellular and mitochondrial ROS that elevated DDR through ataxia-telangiectasia mutated and p53 activation. 6-Gingerol also induced G0/G1 cell cycle arrest and mitochondrial apoptosis by mediating the BAX/BCL-2 ratio and release of cytochrome c. It also exhibited a suppression ability of tumorsphere formation in breast cancer cells. EGFR/Src/STAT3 signaling was also determined to be responsible for p53 activation and that 6-gingerol induced p53-dependent intrinsic apoptosis in breast cancer cells. Therefore, 6-gingerol may be used as a candidate drug against hormone-dependent breast cancer cells.

6-Gingerol, an active constituent of ginger, attenuates lipopolysaccharide-induced oxidation, inflammation, cognitive deficits, neuroplasticity, and amyloidogenesis in rat

This study examined the protective effect of 6-Gingerol (6G) against lipopolysaccharide (LPS)-induced cognitive impairments, oxidative stress, neuroplasticity, amyloidogenesis, and inflammation. Male rats were allocated into six groups in this manner; Group I placed on normal saline only. Group II was treated for 7 days with LPS alone intraperitoneally at 250 µg/kg body weight (bw). Group III received 6G alone at 50 mg/kg bw orally for 14 days. Groups IV and V received 6G at 20 and 50 mg/kg bw for 7 days, respectively, and LPS for another 7 days to induce neurotoxicity. Group VI received 5 mg/kg bw of donepezil for 7 days and LPS for 7 days. Pretreatment with 20 and 50 mg/kg bw of 6G protected against LPS-mediated learning and memory function, and also locomotor and motor deficits. Besides, 20 and 50 mg/kg bw 6G mitigated LPS-induced alteration in markers of oxidative stress. Furthermore, induction of amyloidogenesis associated with disruption of histoarchitecture and high expression of interleukin 1β, inducible nitric oxide synthase, amyloid precursor protein (APP), β-secretase 1, and brain-derived neurotrophic factor by LPS was mitigated by the two doses of 6G in the rat hippocampus and cerebral cortex region of the brain. 6G pretreatment at the two doses mitigated LPS-mediated histopathological changes in the hippocampus and cerebral cortex of rats. Overall, our results demonstrate that the protective effect of 6G is mediated through the reversal of neurobehavioral deficit, oxidative stress, inflammation, and amyloidogenesis, thus making 6G a possible chemoprophylactic agent against brain injury as a result of LPS exposure. PRACTICAL APPLICATIONS: In the search for a holistic prevention of inflammation-associated neurodegeneration, nutraceuticals are becoming prominent. Hence, this study presents 6G, an active constituent of ginger, as a chemoprotective, antioxidant, and anti-inflammatory agent, which is able to ameliorate cognitive impairments, oxidative stress, neuroplasticity, amyloidogenesis, and inflammation in LPS-induced rat model of neuroinflammation.

6-Gingerol attenuates ventilator-induced lung injury via anti-inflammation and antioxidative stress by modulating the PPARγ/NF-κBsignalling pathway in rats

Although mechanical ventilation (MV) is indispensable to life-support therapy in critically ill patients, it may promote or aggravatelunginjury known asventilator-inducedlunginjury(VILI). 6-Gingerol is the principal ingredient of ginger with potential anti-inflammatory and antioxidant properties in various diseases. Nevertheless, the role and mechanism of 6-gingerol in the process of VILI has not been explicitly investigated. In the study, we found that pre-treatment with 6-gingerol significantly improved the histological changes and pulmonary oedema, inhibited neutrophil accumulation and the release of early pro-inflammatory cytokines and MPO, and reduced oxidative stress reactions after high MV. Moreover, 6-gingerol treatment also increased PPARγ expression and decreased NF-κB activation in rats subjected to high MV. Furthermore, GW9662, a specific PPARγ inhibitor, was demonstrated to activatethe NF-κB pathway and cancele the protective role of 6-gingerol in VILI. This indicates that 6-gingerol exerted anti-inflammatory and antioxidative stress effects in VILI by activating PPARγ and inhibiting the NF-κBsignalling pathway.

6-gingerol protects nucleus pulposus-derived mesenchymal stem cells from oxidative injury by activating autophagy

BACKGROUND

To date, there has been no effective treatment for intervertebral disc degeneration (IDD). Nucleus pulposus-derived mesenchymal stem cells (NPMSCs) showed encouraging results in IDD treatment, but the overexpression of reactive oxygen species (ROS) impaired the endogenous repair abilities of NPMSCs. 6-gingerol (6-GIN) is an antioxidant and anti-inflammatory reagent that might protect NPMSCs from injury.

AIM

To investigate the effect of 6-GIN on NPMSCs under oxidative conditions and the potential mechanism.

METHODS

The cholecystokinin-8 assay was used to evaluate the cytotoxicity of hydrogen peroxide and the protective effects of 6-GIN. ROS levels were measured by 2´7´-dichlorofluorescin diacetate analysis. Matrix metalloproteinase (MMP) was detected by the tetraethylbenzimidazolylcarbocyanine iodide assay. TUNEL assay and Annexin V/PI double-staining were used to determine the apoptosis rate. Additionally, autophagy-related proteins (Beclin-1, LC-3, and p62), apoptosis-associated proteins (Bcl-2, Bax, and caspase-3), and PI3K/Akt signaling pathway-related proteins (PI3K and Akt) were evaluated by Western blot analysis. Autophagosomes were detected by transmission electron microscopy in NPMSCs. LC-3 was also detected by immunofluorescence. The mRNA expression of collagen II and aggrecan was evaluated by real-time polymerase chain reaction (RT-PCR), and the changes in collagen II and MMP-13 expression were verified through an immunofluorescence assay.

RESULTS

6-GIN exhibited protective effects against hydrogen peroxide-induced injury in NPMSCs, decreased hydrogen peroxide-induced intracellular ROS levels, and inhibited cell apoptosis. 6-GIN could increase Bcl-2 expression and decrease Bax and caspase-3 expression. The MMP, Annexin V-FITC/PI flow cytometry and TUNEL assay results further confirmed that 6-GIN treatment significantly inhibited NPMSC apoptosis induced by hydrogen peroxide. 6-GIN treatment promoted extracellular matrix (ECM) expression by reducing the oxidative stress injury-induced increase in MMP-13 expression. 6-GIN activated autophagy by increasing the expression of autophagy-related markers (Beclin-1 and LC-3) and decreasing the expression of p62. Autophagosomes were visualized by transmission electron microscopy. Pretreatment with 3-MA and BAF further confirmed that 6-GIN-mediated stimulation of autophagy did not reduce autophagosome turnover but increased autophagic flux. The PI3K/Akt pathway was also found to be activated by 6-GIN. 6-GIN inhibited NPMSC apoptosis and ECM degeneration, in which autophagy and the PI3K/Akt pathway were involved.

CONCLUSION

6-GIN efficiently decreases ROS levels, attenuates hydrogen peroxide-induced NPMSCs apoptosis, and protects the ECM from degeneration. 6-GIN is a promising candidate for treating IDD.

[6-Gingerol Pretreatment Alleviates Hypoxia/Reoxygenation-induced H9C2 Cardiomyocyte Injury by Inhibiting Oxidative Stress and Inflammation]

Objetive

To observe the effect of 6-gingerol (6-G) pretreatment on hypoxia/reoxygenation (H/R) induced injury in H9C2 myocardial cell and investigate its related mechanism.

Methods

The H/R in vitro model of cardiomyocytes was prepared by conventional methods. In detail, H9C2 cells were added with the nitrogen-saturated hypoxic liquid, and placed in an incubator, mixed with gas (1% O ₂, 5% CO ₂, 94% N ₂) applying for 15 min. After culturing for 3 h, the cells were taken out and placed in an incubator (37℃, 5% CO ₂) for 1 h. Before establishing the cell model, the cells were pretreated with 6-G, and the cell viability was measured by MTT method to observe the protective effect of different concentrations of 6-G on H/R-induced cell damage. The 6-G mass concentration for pretreatment that led to the highest cell viability was used for follow-up experiments. DCFH-DA fluorescent probe was used to detect the effect of 6-G pretreatment on H9C2 oxidative stress level, and the intracellular oxidative stress was observed with fluorescence microscope and flow cytometry. Western blot method was used to detect the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β) in H/R-induced cell inflammatory responses.

Results

Compared with the H/R group, the cell viability of the 6-G+H/R group began to increase when the concentration of 6-G promoted to50 μg/mL. The cell viability was the highest after pretreated with 200 μg/mL 6-G. Therefore, 200 μg/mL was considered as the best 6-G intervention concentration for subsequent experiment. The content of reactive oxygen species (ROS) in the 200 μg/mL 6-G group had no significant changes compared with the control group (P>0.05), and the ROS fluorescence peak did not migrate significantly. However the ROS content in the H/R group increased significantly compared with the control (P<0.05), and the ROS fluorescence peak shifted to the right. Compared with the H/R group, the ROS content of the 6-G+H/R group decreased (P<0.05), and the ROS fluorescence peak shifted to the left. Compared with the control group, the expressions of TNF-α, IL-6, IL-1β in the 6-G group had no significant changes (P>0.05); the expressions of TNF-α, IL-6, IL-1β in the H/R group increased (P<0.05). Compared with H/R group, the expressions of TNF-α, IL-6 and IL-1β in 6-G+H/R group decreased (P<0.05).

Conclusion

6-G pretreatment can alleviate H/R-induced H9C2 myocardial injury, which may be related to the inhibition of oxidative stress and inflammatory responses.

Stimulation of calcium influx and CK1α by NF-κB antagonist [6]-Gingerol reprograms red blood cell longevity

Chemotherapy-induced anemia (CIA) is a major obstacle in cancer management. Although the mechanisms governing CIA are poorly understood, recent efforts have identified suicidal erythrocyte (red blood cell, RBC) death as a possible cause of CIA. [6]-Gingerol (GNG), a polyphenol extracted from Zingiber officinale plant, exhibits a wide array of biological activities including antimicrobial, antioxidant, anti-inflammatory, immunomodulatory, and anticancer activities, in vitro and in vivo. However, the potential toxicity of GNG to human RBCs remains unexplored. RBCs from heparinized blood were isolated by centrifugation and exposed to antitumor concentrations (10-100 µM) of GNG for 24 hr at 37°C. Hemolysis was calculated from hemoglobin leakage in the supernatant (λ_max  = 405 nm), while cytofluorometric analysis of eryptosis employed Annexin-V-FITC to detect phosphatidylserine (PS) exposure, forward scatter (FSC) to estimate cell volume, Fluo4/AM to measure calcium activity, and H₂ DCFDA to assess oxidative stress. Moreover, zVAD(OMe)-FMK, SB203580, necrostatin-2, staurosporin, and D4476 were used to identify signaling pathways responsive to GNG. GNG induced significant hemolysis at 100 µM, independently of extracellular calcium, and increased Annexin-V-FITC fluorescence that was thoroughly abrogated without extracellular calcium. GNG also enhanced Fluo4 fluorescence and reduced FSC, but had no significant effect on DCF fluorescence. Importantly, the presence of D4476 significantly attenuated GNG-induced hemolysis. In conclusion, GNG stimulates premature RBC death characterized by loss of membrane asymmetry, elevated cytosolic calcium, cell shrinkage, and casein kinase 1α activation. Blocking the activity of calcium channels or CK1α may, therefore, ameliorate the toxic effects of GNG on RBCs. PRACTICAL APPLICATIONS: This report presents a safety assessment of GNG as a chemotherapeutic agent and highlights the novel toxicity of GNG to human RBCs. Our findings provide novel insights that may lead to more efficient utilization of GNG in chemotherapy. Specifically, our data revealed the involvement of calcium channels and casein kinase 1α in mediating GNG-induced premature RBC death, and, therefore, inverse agonists or inhibitors of either pathway may be used as pharmaceutical adjuvants to attenuate the toxic effects of GNG.

Improvement of 6-gingerol production in ginger rhizomes (Zingiber officinale Roscoe) plants by mutation breeding using gamma irradiation

Ginger (Zingiber officinale Roscoe) is a valuable culinary and medicinal plant. The compound 6-gingerol is the main gingerol in ginger rhizomes and it possesses interesting pharmacological and physiological properties. Mutation breeding involved using low doses of gamma radiation (5-30 Gy) to increase the genetic variability in ginger rhizomes (M1 generation). Ginger plants selected from the next generation (M2) were characterized and subjected to quantitative analysis for 6-gingerol content using HPLC of ginger extracts. M2 offspring from a parent ginger rhizome irradiated with 20 Gy was found to have a high 6-gingerol content (38.4 ± 0.01 mg/g methanol extract in comparison to 22.1 ± 0.03 mg/g methanol extract in non-irradiated control samples). Radiation induced genetic variability was also probed and confirmed using RAPD-PCR analysis. This research demonstrates the potential for ginger improvement and to our knowledge is the first to report the use of gamma radiation in breeding ginger plants with enhanced 6-gingerol content.

6-Gingerol attenuates microglia-mediated neuroinflammation and ischemic brain injuries through Akt-mTOR-STAT3 signaling pathway

Neuroinflammation is critical for the pathogenesis of ischemia brain damage. Over-activated microglia-mediated inflammation plays a very important role in ischemia cerebral injuries. 6-Gingerol, obtained from edible ginger (Zingiber Officinale) exhibits protective effects against inflammation. In this study, we found that 6-Gingerol could reduce the size of infarction (P = 0.0184) and improve neurological functions (P = 0.04) at the third day after ischemic brain injury in vivo. Since 6-Gingerol has the anti-inflammatory effects, we further investigated its impacts on neuroinflammation mediated by microglia both in vivo and in vitro. We found that the levels of pro-inflammatory cytokines Interleukin-1 beta (IL-1β, P = 0.0213), Interleukin-6 (IL-6, P = 0.0316), and inducible NO synthase (iNOS, P = 0.0229) in the infarct penumbra were lower in 6-Gingerol treated groups. Furthermore, microglia induced pro-inflammatory cytokines, such as IL-6, IL-1β, incremental intercellular nitric oxide (NO), as well as iNOS were blocked by the treatment of 6-Gingerol in lipopolysaccharide (LPS) stimulated microglia. In terms of mechanism, 6-Gingerol potently suppressed phosphorylation of serine-threonine protein kinase (Akt) - mammalian target of rapamycin (mTOR) - signal transducer and activator of transcription 3 (STAT3) in LPS-treated microglia. Taken together, the present study suggested that 6-Gingerol improved cerebral ischemia injury by suppressing microglia-mediated neuroinflammation by down-regulating Akt-mTOR-STAT3 pathway.

6-Gingerol delays tumorigenesis in benzo[a]pyrene and dextran sulphate sodium-induced colorectal cancer in mice

Colorectal cancer (CRC) has been linked to dietary consumption of benzo[a]pyrene (B[a]P). 6-Gingerol (6-G), a component of ginger has been reported to possess anti-inflammatory and antioxidant activities, but little is known regarding the mechanism of 6-G in CRC chemoprevention. We therefore investigated the effect of 6-G on B[a]P. and dextran sulphate sodium (DSS) induced CRC in mice. Mice in Group I and Group II received corn oil and 6-G orally at 2 ml/kg and 100 mg/kg, respectively for 126 days. Group III were administered 125 mg/kg of B[a]P for 5 days followed by 3 cycles of 4% dextran sulphate sodium (DSS). Group IV received 6-G for 7 days followed by co-administration with 125 mg/kg of B[a]P. for 5 days and 3 cycles of 4% DSS. Tumor formation was reduced and expression of Ki-67, WNT3a, DVL-2 and β-catenin following 6-G exposure. Also, 6-G increases expression of APC, P53, TUNEL positive nuclei and subsequently decreased the expression of TNF-α, IL-1β, INOS, COX-2 and cyclin D1. 6-G inhibited angiogenesis by decreasing the concentration of VEGF, Angiopoietin-1, FGF and GDF-15 in the colon of B[a]P. and DSS exposed mice. Overall, 6-G attenuated B[a]P and DSS-induced CRC in mice via anti-inflammatory, anti-proliferative and apoptotic mechanisms.

6-Gingerol ameliorates sepsis-induced liver injury through the Nrf2 pathway

Sepsis-induced liver injury is very common in intensive care units. Here, we investigated the effects of 6-gingerol on sepsis-induced liver injury and the role of the Nrf2 pathway in this process. 6-Gingerol is the principal ingredient of ginger that exerts anti-inflammatory and antioxidant effects. Using cecal ligation and puncture (CLP) to induce polymicrobial sepsis and related liver injury, we found that mice pre-treated with 6-Gingerol showed less incidences of severe liver inflammation and death than untreated CLP groups. 6-Gingerol administration also inhibited the expression of pyroptosis-related proteins, including NOD-like receptor protein 3 (NLRP3), IL-1β, and caspase-1. Consistent with these findings, 6-gingerol reduced the effects of pyroptosis induced by lipopolysaccharide (LPS) and adenosine 5'-triphosphate (ATP) in RAW 264.7 cells, as evidenced by IL-1β and caspase-1 protein levels in the supernatant and propidium iodide (PI) staining. 6-Gingerol was shown to activate the Nrf2 pathway in vivo and in vitro. Notably, Nrf2 siRNA transfection nullified the inhibitory effects of 6-gingerol on pyroptosis in vitro. In summary, these findings suggested that 6-gingerol alleviated sepsis-induced liver injury by inhibiting pyroptosis through the Nrf2 pathway.

6-Gingerol attenuates macrophages pyroptosis via the inhibition of MAPK signaling pathways and predicts a good prognosis in sepsis

BACKGROUND

Sepsis is a major cause of death for ICU patients. Sepsis development depends heavily on the presence of mature IL-1β cytokine. This study evaluates the potential therapeutic properties of a bioactive compound known as 6-gingerol on sepsis. This compound has previously been demonstrated to possess anti-inflammatory properties both in vivo and in vitro.

METHODS

C57BL/6 mice was used to establish models of sepsis by means of cecal ligation and puncture (CLP). Upon treatment with 6-gingerol, we assessed the survival rate of mice and measured the levels of key pro-inflammatory cytokines in serum and colon tissues. Sepsis pathogenesis was further explored using the RAW264.7 cell line and bone marrow-derived macrophages (BMDMs) treated with ATP and lipopolysaccharide (LPS). The impact of 6-gingerol on pyroptosis was also examined. In addition, we assessed the role of MAPK signaling in 6-gingerol-induced effects in BMDMs and RAW264.7 cells.

RESULTS

In CLP mice, 6-gingerol significantly ameliorated sepsis development, which was associated with the reduction of serum IL-1β. In BMDMs and RAW264.7 cells, 6-gingerol strongly attenuated pyroptosis as well as the release of caspase-1p20, HMGB1, mature IL-1β, IL-18 in response to ATP and LPS treatment. 6-Gingerol conferred these effects by blocking MAPK activation. Exposure to an ERK agonist (EGF) reversed effects of 6-gingerol, causing pyroptosis, LDH and caspase-1p20 release.

CONCLUSIONS

By targeting MAPK signaling, 6-gingerol significantly suppressed secretion of pro-inflammatory cytokines and inhibited macrophage cells pyroptosis resulting in overall inhibition of sepsis development.

6-Gingerol inhibits proliferation in gastric cancer via the STAT3 pathway in vitro

With high incidence and mortality, gastric cancer seriously threatened human's life. It is arduous and necessary to investigate its pathogenesis and dig effective drugs. In this study, we explored the role of 6-Gingerol (GI), a natural active ingredient, in treating gastric cancer cells. MTT assay and colony formation assay were utilized to confirmed that GI can control the proliferation of gastric cancer cells, which is time and concentration-dependent to some extent. The Annexin V-FITC/PI staining results by flow cytometry reveal that GI induces the apoptosis of gastric cancer cells. And a study on further pathways by western blot shows that GI brings about cell apoptosis by inhibiting the activation of STAT3. GI therefore may be a good candidate for treating gastric cancer.

Conversion of 6-gingerol to 6-shogaol in ginger (Zingiber officinale) pulp and peel during subcritical water extraction

Subcritical water extraction is an eco-friendly method for the extraction of less polar compounds without the use of organic solvents. This study determined the extraction conditions that maximize the contents of 6-gingerol and 6-shogaol obtained from ginger pulp and peel. The highest yields of 6-gingerol (0.68 ± 0.08 mg/g), and 6-shogaol (0.39 ± 0.03 mg/g) were obtained from ginger pulp at the extraction conditions of 130 °C/25 min, and 190 °C/15 min. 6-Shogaol content increased with the increasing extraction temperature and extraction time due to the conversion of 6-gingerol to 6-shogaol by thermal cracking. The antioxidant activity of ginger extracts were increased depending on the increasing of 6-shogaol content.

Micromass Methods for the Evaluation of Developmental Toxicants

Chick embryonic heart has recently been utilized as a model to create a micromass (MM) culturing system. The aim was to overcome the ethical barriers arising from testing the embryotoxicity of chemicals using human embryonic cells. The system represents a valuable tool to study the ability of chemicals to interfere with various embryonic developmental processes such as cellular communication, differentiation, cellular activity, and proliferation, where the disturbance any of them could result in maldevelopment. The system can also be utilized to investigate ROS production and expression of several transmembrane proteins to study their roles in chemical-induced teratogenicity or embryotoxicity.

Fabrication of 6-gingerol, doxorubicin and alginate hydroxyapatite into a bio-compatible formulation: enhanced anti-proliferative effect on breast and liver cancer cells

Ample attention has been devoted to the construction of anti-cancer drug delivery systems with increased stability, and controlled and targeted delivery, minimizing toxic effects. In this study we have designed a magnetically attractive hydroxyapatite (m-HAP) based alginate polymer bound nanocarrier to perform targeted, controlled and pH sensitive drug release of 6-gingerol, doxorubicin, and their combination, preferably at low pH environments (pH 5.3). They have exhibited higher encapsulation efficiency which is in the range of 97.4-98.9% for both 6-gingerol and doxorubicin molecules whereas the co-loading has accounted for a value of 81.87 ± 0.32%. Cell proliferation assays, fluorescence imaging and flow cytometric analysis, demonstrated the remarkable time and dose responsive anti-proliferative effect of drug loaded nanoparticles on MCF-7 cells and HEpG2 cells compared with their neat counter parts. Also, these systems have exhibited significantly reduced toxic effects on non-targeted, non-cancerous cells in contrast to the excellent ability to selectively kill cancerous cells. This study has suggested that this HAP based system is a versatile carrier capable of loading various drug molecules, ultimately producing a profound anti-proliferative effect.

6-gingerol ameliorates age-related hepatic steatosis: Association with regulating lipogenesis, fatty acid oxidation, oxidative stress and mitochondrial dysfunction

The prevalence of NAFLD increases with age. As the main active ingredient of ginger, 6-gingerol significantly improves lipid metabolism abnormalities in adult rodents. However, few studies have reported its effect on age-related NAFLD. This study was to investigate the effects of 6-gingerol on age-related hepatic steatosis and its potential targets. As expected, 6-gingerol dramatically normalized the hepatic triglyceride content, plasma insulin and HOMA-IR index of ageing rats. Mechanistically, 6-gingerol affected lipid metabolism by increasing β-oxidation and decreasing lipogenesis through activation of PPARα and CPT1α and inhibition of DGAT-2. Furthermore, 6-gingerol reversed the decreases in citrate, Cs and ATP, lessened the damage caused by ROS, and upregulated mitochondrial marker enzymes NOX, SDH, and SIRT3 in the ageing liver, indicating its ability to strengthen mitochondrial function. Our results showed 6-gingerol exerted a positive effect on insulin sensitivity by regulating Akt. In conclusion, the hepatic anti-steatotic effect of 6-gingerol is associated with inhibition of de novo lipogenesis, upregulation of fatty acid oxidation, reduction in oxidative stress and synergistic enhancement of mitochondrial function.

Longevity and Stress Resistant Property of 6-Gingerol from Zingiber officinale Roscoe in Caenorhabditis elegans

In order to discover lifespan-extending compounds made from natural resources, activity-guided fractionation of Zingiber officinale Roscoe (Zingiberaceae) ethanol extract was performed using the Caenorhabditis elegans (C. elegans) model system. The compound 6-gingerol was isolated from the most active ethyl acetate soluble fraction, and showed potent longevity-promoting activity. It also elevated the survival rate of worms against stressful environment including thermal, osmotic, and oxidative conditions. Additionally, 6-gingerol elevated the antioxidant enzyme activities of C. elegans, and showed a dose-depend reduction of intracellular reactive oxygen species (ROS) accumulation in worms. Further studies demonstrated that the increased stress tolerance of 6-gingerol-mediated worms could result from the promotion of stress resistance proteins such as heat shock protein (HSP-16.2) and superoxide dismutase (SOD-3). The lipofuscin levels in 6-gingerol treated intestinal worms were decreased in comparison to the control group. No significant 6-gingerol-related changes, including growth, food intake, reproduction, and movement were noted. These results suggest that 6-gingerol exerted longevity-promoting activities independently of these factors and could extend the human lifespan.

Formulation, Characterization, and Pharmacokinetic Studies of 6-Gingerol-Loaded Nanostructured Lipid Carriers

In this study, an optimized nanostructured lipid carriers (NLCs) were developed and investigated for improving the solubility and oral availability of 6-Gingerol (6G), an active and abundant component of ginger with limited applications due to its poor water solubility plus oral biological availability. The NLCs consisted of a solid lipid (glyceryl monostearate), another liquid lipid (decanoyl/octanoyl-glycerides) and mixed surfactants (Tween 80 and Poloxamer 188), and was prepared by high pressure homogenization method. The optimal 6G-NLC formulation was evaluated through physical properties such as appearance, mean particle size, zeta potential, encapsulation efficiency, and in vitro drug release, alongside techniques viz., transmission electron microscopy (TEM), differential scanning calorimetry (DSC), as well as powder X-ray diffraction (XRD). Pharmacokinetics were also evaluated in rats. The 6G-NLCs prepared with optimal formulation exhibited a homogenous spherical shape with mean particle size and zeta potential of 63.59 ± 5.54 nm and - 12.18 ± 1.06 mV. Encapsulation efficiency and drug loading were 76.71 ± 1.11 and 1.17 ± 0.35%, respectively. In vitro release profile of 6G from NLCs was sustained and fitted with Weibull equation. After oral administration of the 6G-NLCs, drug concentrations in serum, MRT, and AUC_0-t were significantly higher as compared with the free 6G suspension. All these results indicated that the developed NLC formulation could be effective and promising drug carriers to improve the water solubility of 6G while sustaining the drug release as well as prolonging in vivo acting time of the drug coupled with oral bioavailability enhancement.

Protective mechanisms of 6-gingerol in dextran sulfate sodium-induced chronic ulcerative colitis in mice

Ulcerative colitis (UC) is a relapsing and remitting inflammatory disease of the colon, with an increasing incidence worldwide. 6-Gingerol (6G) is a bioactive constituent of Zingiber officinale, which has been reported to possess various biological activities. This study was designed to evaluate the role of 6G in chronic UC. Chronic UC was induced in mice by three cycles of 2.5% dextran sulfate sodium (DSS) in drinking water. Each cycle consisted of 7 days of 2.5% DSS followed by 14 days of normal drinking water. 6G (100 mg/kg) and a reference anti-colitis drug sulfasalazine (SZ) (100 mg/kg) were orally administered daily to the mice throughout exposure to three cycles of 2.5% DSS. Administration of 6G and SZ significantly prevented disease activity index and aberrant crypt foci formation in DSS-treated mice. Furthermore, 6G and SZ suppresses immunoexpression of tumor necrosis factor alpha, interleukin-1β, inducible nitric oxide synthase, Regulated on activation, normal T cell expressed and secreted (RANTES), and Monocyte chemoattractant protein-1 (MCP-1) in the DSS-treated mice. 6G effectively protected against colonic oxidative damage by augmenting the antioxidant status with marked decrease in lipid peroxidation levels in DSS-treated mice. Moreover, 6G significantly inhibited nuclear factor kappa B (P65), p38, cyclooxygenase-2, and β-catenin whereas it enhanced IL-10 and adenomatous polyposis coli expression in DSS-treated mice. In conclusion, 6G prevented DSS-induced chronic UC via anti-inflammatory and antioxidative mechanisms and preservation of the Wnt/β-catenin signaling pathway.

6-Gingerol attenuates LPS-induced neuroinflammation and cognitive impairment partially via suppressing astrocyte overactivation

6-Gingerol, the major component of gingerols extracted from Zingiber officinale, has been shown to exhibit anti-inflammatory and antioxidant bioactivities. Since neuroinflammation plays an important role in neurodegenerative diseases, such as Alzheimer's disease (AD), and astrocytes have been considered important in the process of neurodegeneration, it was of interest to know whether 6-gingerol reduced astrocytes activation or even attenuated cognitive impairment. Here we examined the neuroprotective effects of 6-gingerol in lipopolysaccharide (LPS)-induced disorder models both in vitro and in vivo. C6 astroglioma cells treated with LPS were found to release excessive pro-inflammatory cytokines, including TNF-α and IL-6, and also increase intercellular ROS, NO, and iNOS (i.e. NOS2). All these were blocked by 6-gingerol in a concentration-dependent manner. The spatial learning and memory of rats challenged with LPS (10 μg, i.c.v.) in the absence or presence of 6-gingerol were evaluated using the Morris water-maze (MWM) test. 6-Gingerol attenuated LPS-induced imapirement of MWM learning and memory in a dose-dependent manner. Besides, 6-gingerol inhibited LPS-induced increases in levels of GFAP and TNF-α in the rat brain. The results suggest that 6-gingerol suppresses astrocyte overactivation, through which it contributes to improvement of cognitive ability.

Probing the interaction of the phytochemical 6-gingerol from the spice ginger with DNA

6-Gingerol [5-hydroxy-1-(4-hydroxy-3-methoxyphenyl) decan-3-one], the bio-active ingredient of the popular Indian spice ginger (Zingiber officinale Roscoe), is well-known for its pharmacological and physiological actions. The potent antioxidant, antiemetic, antiulcer, antimicrobial, analgesic, hypoglycemic, antihypertensive, antihyperlipidemic, immunostimulant, anti-inflammatory, cardiotonic, and cancer prevention activities of 6-Gingerol has been investigated and explored. 6-Gingerol is a good candidate for the treatment of various cancers including prostrate, pancreatic, breast, skin, gastrointestinal, pulmonary, and renal cancer. In this study we report for the first time the molecular recognition of 6-Gingerol with calf thymus DNA (ctDNA) through experimental and molecular modeling techniques confirming a minor groove binding mode of 6-Gingerol with ctDNA. Fluorescence and UV-vis spectroscopic studies confirm the complex formation of 6-gingerol with ctDNA. The energetics and thermodynamics of the interaction of 6-Gingerol with ctDNA was explored by Isothermal Titration Calorimetry (ITC) and Differential Scanning Calorimetry (DSC). The ctDNA helix melting upon 6-Gingerol binding was examined by melting temperature Tm analysis. Further the electrophoretic mobility shift assay confirms a possible groove binding of 6-Gingerol with ctDNA. Molecular docking and Molecular dynamics (MD) studies provide a detailed understanding on the interaction of 6-Gingerol binding in the minor groove of DNA which supports experimental results.

Assessment of anti-cancerous potential of 6-gingerol (Tongling White Ginger) and its synergy with drugs on human cervical adenocarcinoma cells

The anti-cancerous activity of 6-gingerol extracted from Tongling White Ginger was investigated. 6-Gingerol inhibited the growth of HeLa cells with IC50 (96.32 μM) and IC80 (133.01 μM) and led to morphological changes, induced the cell cycle arrest in G0/G1-phase and ultimately resulted into apoptosis. Among cell cycle-related genes and proteins, the expression of cyclin (A, D1, E1) reduced, while of CDK-1, p21 and p27 showed slight decrease, except cyclin B1 and E1 (protein). Western blotting reported the induction of apoptosis with an increased Bax/Bcl-2 ratio, release of cytochrome c, cleavage of caspase-3, -8, -9 and PRPP in treated cells. 6-Gingerol activated AMPK, but inhibited PI3K/AKT phosphorylation with reduced P70S6K expression and also suppressed the mTOR phosphorylation. 6-Gingerol with 5-FU and Ptx resulted in 83.2% and 52% inhibition respectively, this synergy have stimulated apoptosis proteins more efficiently as compared to 6-Gingerol alone (10.75%) under in vitro conditions.

Protective effects of 6-Gingerol on vascular endothelial cell injury induced by high glucose via activation of PI3K-AKT-eNOS pathway in human umbilical vein endothelial cells

6-Gingerol (6-Gin), an active constituent of Zingiber officinale, has been reported to have anti-inflammatory, anti-oxidative, anti-cancerous etc. bioactivities. However, little is known about its endothelial protective effects and the underlying mechanisms. In this study, our purpose was to investigate the protective effects of 6-Gin and its underlying mechanisms. HUVECs were exposed to high glucose (HG, 33mM glucose) for 48h, followed by 50μM 6-Gin with or without LY294002 (10μM), AKT inhibitor IV (0.5μM) or L-NAME (5mM) for another 24h. Cell viability, levels of NO, LDH and ROS were detected. In addition, the expression levels of IKK, IRS-1, PI3K, AKT, eNOS and their phosphorylated proteins were measured by western blots. Compared with the control, HUVECs were significantly impaired by HG, characterized by decreased levels of the cell viability, NO, pY458-PI3K, pS473-AKT and pS1177-eNOS while increased levels of LDH, pS176-IKK, and p-S312-IRS-1. Conversely, 6-Gin remarkably protected HUVECs against HG-induced injury in a concentration- and time-dependent manner. However, the protective effects of 6-Gin were abolished by co-treatment with LY294002, AKT inhibitor IV or L-NAME at the HG state. Collectively, 6-Gin attenuated the injury of HUVECs induced by HG through the activation of PI3K-AKT-eNOS signal pathway. The findings provide a novel potential for 6-Gin to prevent and treat the angiopathy resulting from diabetes mellitus.

6-Gingerol protects intestinal barrier from ischemia/reperfusion-induced damage via inhibition of p38 MAPK to NF-κB signalling

Intestinal ischemia reperfusion (I/R) injury caused by severe trauma, intestinal obstruction, and operation is one of the tough challenges in clinic. 6-Gingerol (6G), a main active ingredient of ginger, is found to have anti-microbial, anti-inflammatory, anti-oxidative, and anti-cancer activities. The present study was designed to characterize the potential protective effects of 6G on rat intestinal I/R injury and reveal the correlated mechanisms. Rat intestinal I/R model was established with clamping the superior mesenteric artery (SMA) and 6G was intragastrically administered for three consecutive days before I/R injury. Caco-2 and IEC-6 cells were incubated under hypoxia/reoxygenation (H/R) conditions to simulate I/R injury in vitro. The results showed that 6G significantly alleviated intestinal injury in I/R injured rats by reducing the generation of oxidative stress and inhibiting p38 MAPK signaling pathway. 6G significantly reduced MDA level and increased the levels of SOD, GSH, and GSH-Px in I/R injured intestinal tissues. 6G significantly decreased the production of proinflammatory cytokines including TNF-α, IL-1β, and IL-6, and inhibited the expression of inflammatory mediators iNOS/NO in I/R injured intestinal tissues. The impaired intestinal barrier function was restored by using 6G in I/R injured rats and in both Caco-2 and IEC-6 cells characterized by inhibiting p38 MAPK phosphorylation, nuclear translocation of NF-κB, and expression of myosin light chain kinase (MLCK) protein. 6G also reduced the generation of reactive oxygen species (ROS) in both Caco-2 and IEC-6 cells. In vitro transfection of p38 MAPK siRNA mitigated the impact of 6G on NF-κB and MLCK expression, and the results further corroborated the protective effects of 6G on intestinal I/R injury by repressing p38 MAPK signaling. In conclusion, the present study suggests that 6G exerts protective effects against I/R-induced intestinal mucosa injury by inhibiting the formation of ROS and p38 MAPK activation, providing novel insights into the mechanisms of this therapeutic candidate for the treatment of intestinal injury.

Effect of 6-gingerol on AMPK- NF-κB axis in high fat diet fed rats

OBJECTIVES

Adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a central role in metabolic homeostasis and regulation of inflammatory responses through attenuation of nuclear factor kappa-B (NF-κB), Thus AMPK may be a promising pharmacologic target for the treatment of various chronic inflammatory diseases. We examined the effect of 6-gingerol, an active ingredient of ginger on AMPK-NF-κB pathway in high fat diet (HFD) rats in comparison to fish oil.

METHODS

Protein levels of AMPK-α1 and phosphorylated AMPK-α1 were measured by western blot while Sirtuin 6 (Sirt-6), resistin and P65 were estimated by RT-PCR, TNF-α was determined by ELISA, FFAs were estimated chemically as well as the enzymatic determination of the metabolic parameters.

RESULTS

6-Gingerol substantially enhanced phosphorylated AMPK-α1 more than fish oil and reduced the P65 via upregulation of Sirt-6 and downregulation of resistin, and resulted in attenuation of the inflammatory molecules P65, FFAs and TNF-α more than fish oil treated groups but in an insignificant statistical manner, those effects were accompanied by a substantial hypoglycemic effect.

CONCLUSION

Gingerol treatment effectively modulated the state of inflammatory privilege in HFD group and the metabolic disorders via targeting the AMPK-NF-κB pathway, through an increment in the SIRT-6 and substantial decrement in resistin levels.

A phase II randomized double-blind placebo-controlled study of 6-gingerol as an anti-emetic in solid tumor patients receiving moderately to highly emetogenic chemotherapy

6-Gingerol is a natural compound extracted from ginger. Preclinical studies demonstrated that 6-gingerol has an anti-emetic activity by inhibiting neurokinin-1, serotonin, and dopamine receptors. Several clinical trials examined crude ginger powder for preventing chemotherapy-induced nausea and vomiting (CINV), but none of them was conducted with a standardized bioactive compound. Patients who received moderately to highly emetogenic adjuvant chemotherapy were randomized to receive 6-gingerol 10 mg or placebo orally twice daily for 12 weeks. Ondansetron, metoclopramide, and dexamethasone were given to all patients. The primary endpoint was complete response (CR) rate defined as no emesis or rescue treatment at any time. Eighty-eight patients were randomized to receive 6-gingerol (N = 42) or placebo (N = 46). Most patients received highly emetogenic chemotherapy (93%). Overall CR rate was significantly higher in 6-gingerol group as compared with that of the placebo (77 vs. 32%; P < 0.001). The difference in means of appetite score was significant (P = 0.001) and more noticeable over time. Mean FACT-G score indicating quality of life was significantly higher (86.21) in 6-gingerol group at 64 days as compared with that of placebo group (72.36) (P < 0.001). No toxicity related to 6-gingerol was observed. Patients treated with 6-gingerol reported significantly less grade 3 fatigue (2 vs. 20%; P = 0.020). 6-Gingerol significantly improved overall CR rate in CINV, appetite and quality of life in cancer patients receiving adjuvant chemotherapy. A phase III randomized study of 6-gingerol is warranted to confirm these results.

The effects of 6-Gingerol on reproductive improvement, liver functioning and Cyclooxygenase-2 gene expression in estradiol valerate - Induced polycystic ovary syndrome in Wistar rats

6-Gingerol is the major pungent ingredient of ginger with anti-inflammatory and antioxidant properties. In this study, we evaluate the effects of 6-gingerol on the biochemical parameters and ovarian histological improvements in estradiol valerate (EV) induced PCOS rats. Thirty six female Wistar rats were divided into 4 groups: control, received normal diet, PCOS control, received 4 mg/kg EV injection for 28 days and two experimental groups, received an EV injection for 28 days and followed by 6-gingerol (200 μg/_kg and 400 μg/_kg) for 14 days. The administration of EV led to increase body and ovarian weights, abnormality in serum sex steroid profile, decrease in antioxidant activity and increase in COX-2 gene expression. 6-gingerol treatments, particularly the 400 μg/_kg dose, markedly attenuated these alterations. 6-gingerol showed beneficial effects in the EV induced PCOS rats via decreased expression of COX-2, restored biochemical parameters to normal and decreased of cysts in the ovaries.

6-Gingerol prevents MEHP-induced DNA damage in human umbilical vein endothelia cells

Mono (2-ethylhexyl) phthalate (MEHP) is the principal metabolite of di (2-etylhexyl) phthalate, which is widely used as a plasticizer, especially in medical devices. MEHP has toxic effects on cardiovascular system. The aim of this study was to investigate the possibility that 6-gingerol may inhibit the oxidative DNA damage of MEHP in human umbilical vein endothelial cells (HUVECs) and the potential mechanism. The comet assay was used to monitor DNA strand breaks. We have shown that 6-gingerol significantly reduced the DNA strand breaks caused by MEHP. MEHP increased the levels of reactive oxygen species and malondialdehyde, decreased the level of glutathione and activity of superoxide dismutase, and altered the mitochondrial membrane potential. In addition, DNA damage-associated proteins (p53 and p-Chk2 (T68)) were significantly increased by the treatment of MEHP. Those effects can all be protected by 6-gingerol. The results firmly indicate that 6-gingerol may have a strong protective ability against the DNA damage caused by MEHP in HUVECs, and the mechanism may relate to the antioxidant activity.

Revealing the effect of 6-gingerol, 6-shogaol and curcumin on mPGES-1, GSK-3β and β-catenin pathway in A549 cell line

BACKGROUND AND AIM

In our study, anticancer effects of 6-gingerol, 6-shogaol from ginger and curcumin from turmeric were investigated and the results were compared with each other. We aimed to reveal their effects on microsomal prostaglandine E2 synthase 1 (mPGES-1) which is related with cancer progression and inflammation as well as β-catenin and glycogen synthase kinase 3β (GSK-3β) that are the main components of Wnt/GSK3 pathway. As it is known activation of GSK-3β and high levels of mPGES-1 pathway leads to cell proliferation and aggravates cancer progression. Therefore both of them are potential targets for cancer therapy. 6-shogaol and 6-gingerol' s effect on this pathway is not known very well up to now while curcumin that is known as an mPGES-1 inhibitor has anticancer properties via this pathway and many other pathways. Besides being in Zingiberaceae family, ginger's 6-gingerol and 6-shogaol have a molecular similarity with turmeric's curcumin. In our study we investigated their effects using a popular non small lung cancer cell line named A549 which expresses mPGES-1 and has active GSK3β pathway. IL-1β was used for inducing mPGES-1 and enabling the cancer characteristics such as cell proliferation. So compounds that inactivates or decreases the level of these components might be potential anticancer agents.

MATERIALS AND METHODS

A549 cells were incubated with interleukin 1β (IL-1β) for 24 h in order to maintain mPGES-1 enzyme induction. Experiments were performed both on IL-1β and non-IL-1β group. Real time cell analysis was performed to determine the cytotoxicity. Samples for western blotting and RT-PCR were collected after 24 h incubation with compounds to determine the amount of mPGES-1, GSK-3β, p-GSK-3β, β-catenin protein and mRNA. PGE2 which is the end product of mPGES-1 was measured by using ELISA kit.

RESULTS

As a result of cell profile assay, cells exposed to IL-1β proliferate faster than non-IL-1β ones. This shows that induced mPGES-1 might play a role through GSK3β pathway and 24 h IC50 value of 6-shogaol is 62 μM. IL-1β increased protein and mRNA levels of mPGES-1, p-GSK-3β, β-catenin and GSK-3β in control group. Effects of curcumin and 6-shogaol on these parameters were against IL-1β's effect while 6-gingerol was not effective at all. Furthermore, 6-shogaol and curcumin might be effective on GSK3β pathway via lowering PGE2 levels.

CONCLUSION

We saw that 6-shogaol is as effective as curcumin on this pathway and our study shows that 6-shogaol might show its anticancer properties via mPGES-1 and GSK3β pathway. May be these results might used for designing in vivo studies in future.

6-Gingerol induces autophagy to protect HUVECs survival from apoptosis

6-Gingerol, the major pharmacologically-active component of ginger, has the potential to prevent heart disease. However, the mechanisms are not well understood. In this study, the protective effect of 6-gingerol against hydrogen peroxide-induced apoptosis in human umbilical vein endothelial cells (HUVECs) was investigated. Apoptosis was detected by Hoechst 33342 and Flow cytometry analysis. To further elucidate the crosstalk between apoptosis and autophagy, we tested the expression of autophagy related proteins, LC3B, Bcl-2, Beclin1, AKT, p-AKT, mechanistic target of rapamycin (mTOR), and p-mTOR. Furthermore, mitochondrial membrane potential and the intracellular generation of reactive oxygen species (ROS) were also investigated. Our data revealed that 6-gingerol significantly reduced apoptosis by inducing autophagy. It has been demonstrated that 6-gingerol suppressed the phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR signaling pathway, increased the expression of Beclin1 to promote autophagy, and increased Bcl-2 expression to inhibit apoptosis. In addition, the damage of mitochondrial was protected, and ROS level was decreased by 6-gingerol. These firmly indicate 6-gingerol has a strong protective ability against the apoptosis caused by oxidative stress in HUVECs, and the mechanism may relate to the induction of autophagy. Our data suggest 6-gingerol may be beneficial in the prevention of atherosclerosis.

Separation and preparation of 6-gingerol from molecular distillation residue of Yunnan ginger rhizomes by high-speed counter-current chromatography and the antioxidant activity of ginger oils in vitro

Molecular distillation residue (MD-R) from ginger had the most total phenol content of 247.6mg gallic acid equivalents per gram (GAE/g) among the ginger oils. High-speed counter-current chromatography (HSCCC) technique in semi-preparative scale was successfully performed in separation and purification of 6-gingerol from MD-R by using a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:2:5:7, v/v/v/v). The target compound was isolated, collected, purified by HSCCC in the head-tail mode, and then analyzed by HPLC. A total of 90.38±0.53mg 6-gingerol was obtained from 600mg MD-R, with purity of 99.6%. In addition, the structural identification of 6-gingerol was performed by EI/MS, (1)H NMR and (13)C NMR. Moreover, the orders of antioxidant activity were vitamin E (VE)>supercritical fluid extraction oleoresin (SFE-O)=MD-R=6-gingerol>molecular distillation essential oil (MD-EO) and butylated hydroxytoluene (BHT)=VE>6-gingerol>MD-R=SFE-O>MD-EO, respectively in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging and β-Carotene bleaching.

Cancer Chemoprevention Effects of Ginger and its Active Constituents: Potential for New Drug Discovery

Ginger is a commonly used spice and herbal medicine worldwide. Besides its extensive use as a condiment, ginger has been used in traditional Chinese medicine for the management of various medical conditions. In recent years, ginger has received wide attention due to its observed antiemetic and anticancer activities. This paper reviews the potential role of ginger and its active constituents in cancer chemoprevention. The phytochemistry, bioactivity, and molecular targets of ginger constituents, especially 6-shogaol, are discussed. The content of 6-shogaol is very low in fresh ginger, but significantly higher after steaming. With reported anti-cancer activities, 6-shogaol can be served as a lead compound for new drug discovery. The lead compound derivative synthesis, bioactivity evaluation, and computational docking provide a promising opportunity to identify novel anticancer compounds originating from ginger.