Differential Inhibition of T Lymphocyte Proliferation and Cytokine Synthesis by [6]-Gingerol, [8]-Gingerol, and [10]-Gingerol

Ginger-derived bioactive compounds attenuate the Toll-like receptor mediated responses of human dendritic cells

Ginger has been used for thousands of years for the treatment of many illnesses, from nausea to migraines. Recently, an interest has grown in ginger compounds in the context of autoimmune and inflammatory diseases due to their significant anti-inflammatory effects. Nevertheless, the effects and mechanism of action of these phytochemicals in human immune cells, particularly in dendritic cells (DCs) are unclear. In the present study, we investigated the effects of 6-gingerol and 6-shogaol, the major compounds found in ginger rhizome, on the functionality of primary human monocyte-derived DCs (moDCs). Here we report for the first time that 6-gingerol and 6-shogaol dampen the immunogenicity of human DCs by inhibiting their activation, cytokine production and T cell stimulatory ability. In particular, the bioactive compounds of ginger dose-dependently inhibited the upregulation of activation markers, and the production of different cytokines in response to synthetic Toll-like receptor (TLR) ligands. Moreover, both compounds could significantly reduce the Escherichia coli-triggered cytokine production and T cell stimulatory capacity of moDCs. We also provide evidence that the ginger-derived compounds attenuate DC functionality via inhibiting the nuclear factor-κB (NF-kB), mitogen activated protein kinase (MAPK), and mammalian target of rapamycin (mTOR) signaling cascades. Further, 6-shogaol but not 6-gingerol activates the AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor 2 (NRF2) pathways that might contribute to its anti-inflammatory action. Altogether, our results indicate that ginger-derived phytochemicals exert their anti-inflammatory activities via multiple mechanisms and suggest that 6-shogaol is more potent in its ability to suppress DC functionality than 6-gingerol.

Immunomodulatory and anti-inflammatory therapeutic potential of gingerols and their nanoformulations

Ginger (Zingiber officinale Roscoe), a member of the Zingiberaceae family, is one of the most popular spices worldwide, known since ancient times, and used both as a spice and a medicinal plant. The phenolic compounds found in ginger are predominantly gingerols, shogaols, and paradols. Gingerols are the major phenolic compounds found in fresh ginger and contain mainly 6-gingerol as well as 4-, 5-, 8-, 10-, and 12-gingerols. Gingerols possess a wide array of bioactivities, such as antioxidant and anticancer, among others. Regarding the different array of biological activities and published data on the mechanisms underlying its action, the complex interaction between three key events, including inflammation, oxidative stress, and immunity, appears to contribute to a plethora of pharmacological activities of this compound. Among these, the immunomodulatory properties of these compounds, which attract attention due to their effects on the immune system, have been the focus of many studies. Gingerols can alleviate inflammation given their ability to inhibit the activation of protein kinase B (Akt) and nuclear factor kappa B (NF-κB) signaling pathways, causing a decrease in proinflammatory and an increase in anti-inflammatory cytokines. However, given their low bioavailability, it is necessary to develop new and more effective strategies for treatment with gingerols. In order to overcome this problem, recent studies have addressed new drug delivery systems containing gingerols. In this review, the immunomodulatory activities of gingerol and its underlying mechanisms of action combined with the contributions of developed nanodrug delivery systems to this activity will be examined.

Bioactive Compounds from the Zingiberaceae Family with Known Antioxidant Activities for Possible Therapeutic Uses

The Zingiberaceae family is a rich source of diverse bioactive phytochemicals. It comprises about 52 genera and 1300 species of aromatic flowering perennial herbs with characteristic creeping horizontal or tuberous rhizomes. Notable members of this family include ginger (Zingiber officinale Roscoe), turmeric (Curcuma longa L.), Javanese ginger (Curcuma zanthorrhiza Roxb.), and Thai ginger (Alpinia galanga L.). This review focuses on two main classes of bioactive compounds: the gingerols (and their derivatives) and the curcuminoids. These compounds are known for their antioxidant activity against several maladies. We highlight the centrality of their antioxidant activities with notable biological activities, including anti-inflammatory, antidiabetic, hepatoprotective, neuroprotective, antimicrobial, and anticancer effects. We also outline various strategies that have been applied to enhance these activities and make suggestions for research areas that require attention.

10-gingerol, a natural AMPK agonist, suppresses neointimal hyperplasia and inhibits vascular smooth muscle cells proliferation

Background: Abnormal proliferation of vascular smooth muscle cells (VSMCs) in the intimal region is a key event in the development of neointimal hyperplasia. 10-G, a bioactive compound found in ginger,...

Ginger from Farmyard to Town: Nutritional and Pharmacological Applications

Ginger (Zingiber officinale) is one of the most widely used natural products consumed as a spice and medicine for treating diabetes, flatulent intestinal colic, indigestion, infertility, inflammation, insomnia, a memory booster, nausea, rheumatism, stomach ache, and urinary tract infections. To date, over 400 bioactive components, such as diarylheptanoids, gingerol analogues, phenylalkanoids, sulfonates, monoterpenoid glycosides, steroids, and terpene compounds have been derived from ginger. Increasing evidence has revealed that ginger possesses a broad range of biological activities, especially protective effects against male infertility, nausea and vomiting, analgesic, anti-diabetic, anti-inflammatory, anti-obesity, and other effects. The pharmacological activities of ginger were mainly attributed to its active phytoconstituents such as 6-gingerol, gingerdiol, gingerol, gingerdione, paradols, shogaols, sesquiterpenes, zingerone, besides other phenolics and flavonoids. In recent years, in silico molecular docking studies revealed that gingerol (6-gingerol, 8-gingerol, and 10-gingerol) and Shogaol (6-shogaol, 8-shogaol, 10-shogaol) had the best binding affinities to the receptor protein in disease conditions such as diabetes, inflammation, obesity, and SARS-CoV-2. Furthermore, some clinical trials have indicated that ginger can be consumed for alleviation of nausea and vomiting induced by surgery, pain, diabetes, obesity, inflammation, male infertility. This review provides an updated understanding of the scientific evidence on the development of ginger and its active compounds as health beneficial agents in future clinical trials.

Therapeutic potential of ginger against COVID-19: Is there enough evidence?

In addition to the respiratory system, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strikes other systems, including the digestive, circulatory, urogenital, and even the central nervous system, as its receptor angiotensin-converting enzyme 2 (ACE2) is expressed in various organs, such as lungs, intestine, heart, esophagus, kidneys, bladder, testis, liver, and brain. Different mechanisms, in particular, massive virus replication, extensive apoptosis and necrosis of the lung-related epithelial and endothelial cells, vascular leakage, hyper-inflammatory responses, overproduction of pro-inflammatory mediators, cytokine storm, oxidative stress, downregulation of ACE2, and impairment of the renin-angiotensin system contribute to the COVID-19 pathogenesis. Currently, COVID-19 is a global pandemic with no specific anti-viral treatment. The favorable capabilities of the ginger were indicated in patients suffering from osteoarthritis, neurodegenerative disorders, rheumatoid arthritis, type 2 diabetes, respiratory distress, liver diseases and primary dysmenorrheal. Ginger or its compounds exhibited strong anti-inflammatory and anti-oxidative influences in numerous animal models. This review provides evidence regarding the potential effects of ginger against SARS-CoV-2 infection and highlights its antiviral, anti-inflammatory, antioxidative, and immunomodulatory impacts in an attempt to consider this plant as an alternative therapeutic agent for COVID-19 treatment.

Assessing the Impact of Phytochemicals on Immune Checkpoints: Implications for Cancer Immunotherapy

Phytochemicals are the basis for many anticancer drugs currently in clinical use, as well as a potential source of future cancer treatments. Some phytochemicals have been found to modify the expression of checkpoint inhibitors of the immune response, as well as kill cancer cells. Cancer cells, in turn, may evade detection by the immune system by expressing molecules such as programmed death ligand 1 (PD-L1) that interacts with programmed cell death 1 (PD-1) on T cells to inhibit T cell activation and effector function. Phytochemicals have direct effects on cancer cells and/or T cells that may impact PD-L1/PD1 interactions, although this may vary depending on the phytochemical in question. Flow cytometric analysis of cancer cells stained with anti-PD-L1 antibodies following treatment with a given phytochemical enables the detection of any alteration in PD-L1 expression. The effect of the phytochemical on T cell function can be assessed using proliferation assays (e.g., tritiated thymidine incorporation, flow cytometric analysis of Oregon Green 488-stained cells) and enzyme-linked immunosorbent assay of interleukin-2 content in culture supernatants. Additional study is needed to better understand the impact of phytochemicals on cancer immunotherapy.

Nutritional implications of ginger: chemistry, biological activities and signaling pathways

Ginger (Zingiber officinale Roscoe) has been used as a food, spice, supplement and flavoring agent and in traditional medicines due to its beneficial characteristics such as pungency, aroma, nutrients and pharmacological activity. Ginger and ginger extracts were reported to have numerous effects, such as those on diabetes and metabolic syndrome, cholesterol levels and lipid metabolism, and inflammation, revealed by epidemiological studies. To understand the beneficial characteristics of ginger, especially its physiological and pharmacological activities at the molecular level, the biological effects of ginger constituents, such as monoterpenes (cineole, citral, limonene and α/β-pinenes), sesquiterpenes (β-elemene, farnesene and zerumbone), phenolics (gingerols, [6]-shogaol, [6]-paradol and zingerone) and diarylheptanoids (curcumin), and the associated signaling pathways are summarized. Ginger constituents are involved in biological activities, such as apoptosis, cell cycle/DNA damage, chromatin/epigenetic regulation, cytoskeletal regulation and adhesion, immunology and inflammation, and neuroscience, and exert their effects through specific signaling pathways associated with cell functions/mechanisms such as autophagy, cellular metabolism, mitogen-activated protein kinase and other signaling, and development/differentiation. Estrogens, such as phytoestrogens, are one of the most important bioactive materials in nature, and the molecular mechanisms of estrogen actions and the assays to detect them have been discussed. The molecular mechanisms of estrogen actions induced by ginger constituents and related applications, such as the chemoprevention of cancers, and the improvement of menopausal syndromes, osteoporosis, endometriosis, prostatic hyperplasia, polycystic ovary syndrome and Alzheimer's disease, were summarized by a comprehensive search of references to understand more about their health benefits and associated health risks.

The effect of ginger supplementation on IL2, TNFα, and IL1β cytokines gene expression levels in patients with active rheumatoid arthritis: A randomized controlled trial

Background: Rheumatoid arthritis (RA) is a chronic autoimmune and inflammatory disease that affects the joints and consequently leads to the destruction of cartilage and bone lesions. Traditionally, ginger has been consumed in treatment of osteoarthritis, joint and muscle pain, neurological diseases, and inflammation of gums, tooth pain, asthma, stroke, diabetes, and constipation. The aim of this study was to determine the effect of ginger on some immunological and inflammatory markers in patients with rheumatoid arthritis. Methods: In this study, which was performed during 2013-2016, 66 patients with active rheumatoid arthritis who referred to the rheumatology clinic at Shariati hospital were en-rolled. Patients were randomly divided into 2 groups: one group consumed 1.5 gr ginger per day, and the other group took roasted wheat flour (placebo), respectively. To determine the effect of confounding factors on the findings of the study, questionnaires for nutrient intake, physical activity, and medication were filled, and BMI was measured. For each participant, at the beginning and end of the study, Serum hs-CRP and mRNA levels of IL-1β, IL-2 and TNF-α were determined by ELISA and Quantitative Real Time PCR, respectively. Statistical analysis was performed using SPSS software. Significance level was set at p<0.05. Results: Results of the study showed ginger powder supplementation caused a significant decline in CRP (p=0.050) and IL-1β mRNA level (p=0.021). TNFα mRNA levels reduced in ginger group compared to placebo groupalthough the difference was not significant between the 2 groups (p=0.093). Ginger had no effects on IL2 gene expression. Conclusion: This study showed that ginger reduces inflammatory factors hs-CRP and IL-1β gene expression in patients with active RA and it seems that ginger can improve the inflam-mation in the patients.

Unraveling the Molecular Mechanism of Traditional Chinese Medicine: Formulas Against Acute Airway Viral Infections as Examples

Herbal medicine, including traditional Chinese medicine (TCM), is widely used worldwide. Herbs and TCM formulas contain numerous active molecules. Basically, they are a kind of cocktail therapy. Herb-drug, herb-food, herb-herb, herb-microbiome, and herb-disease interactions are complex. There is potential for both benefit and harm, so only after understanding more of their mechanisms and clinical effects can herbal medicine and TCM be helpful to users. Many pharmacologic studies have been performed to unravel the molecular mechanisms; however, basic and clinical studies of good validity are still not enough to translate experimental results into clinical understanding and to provide tough evidence for better use of herbal medicines. There are still issues regarding the conflicting pharmacologic effects, pharmacokinetics, drug interactions, adverse and clinical effects of herbal medicine and TCM. Understanding study validation, pharmacologic effects, drug interactions, indications and clinical effects, adverse effects and limitations, can all help clinicians in providing adequate suggestions to patients. At present, it would be better to use herbs and TCM formulas according to their traditional indications matching the disease pathophysiology and their molecular mechanisms. To unravel the molecular mechanisms and understand the benefits and harms of herbal medicine and TCM, there is still much work to be done.

Immune promotive effect of bioactive peptides may be mediated by regulating the expression of SOCS1/miR-155

The present study was designed to evaluate the effect of bioactive hepatic peptide (BHP) on the immune function of mice and to examine the mechanism mediated by the related factors cytokine suppressor of cytokine signaling 1 (SOCS1) and microRNA (miR)-155. The mice were divided into eight groups, including a normal mouse group, normal peptide groups (low-dose, mid-dose and high-dose), an immunosuppressed group, and immunosuppressed with peptide groups (low-dose, mid-dose and high-dose). The proliferative ability of splenic lymphocytes was determined in vitro using a Cell Counting kit-8 assay. Wright's staining was used to assess the phagocytic function of macrophages. Histological changes in the spleen were evaluated by hematoxylin-eosin staining. The relevant factors SOCS1/miR-155 were assessed by immunohistochemistry and reverse transcription fluorescence-quantitative polymerase chain reaction analysis. The levels of the cytokines TGF-β1, IL-10 and IL-17A were determined by enzyme-linked immunosorbent assay. First, the organ index, percentage of lymphocytes, phagocytosis experiments and splenic lymphocyte proliferation test results revealed that the immunodeficient mouse model had been successfully established. Second, compared with the control mice, the normal peptide group mice exhibited increased spleen and thymus indices, percentages of lymphocyte subsets, macrophage phagocytosis percentages, phagocytic indices, splenic lymphocyte proliferation and expression of miR-155; however, the expression of SOCS1 was decreased in the normal peptide groups to varying extents. In addition, the expression of SOCS1 was upregulated, whereas that of miR-155 was downregulated in the immunosuppressed group. Compared with the mice in the immunosuppressed group, the mice in the immunosuppressed with peptide groups had increased spleen and thymus indices, percentages of lymphocyte subsets, macrophage phagocytosis percentages, phagocytic indices, splenic lymphocyte proliferation and expression of miR-155; however, the expression of SOCS1 was decreased in the immunosuppressed with peptide groups to varying extents. Following treatment with BHP, the secretion of TGF-β1 in the spleen of the normal mice and immunosuppressed mice was significantly decreased, and the secretion of IL-10 was significantly increased. No significant difference in the expression of IL-17A was observed among the groups. In summary, BHP improved the immune function of the normal mice and immunosuppressed mice. This data provides a scientific basis for the development of bioactive peptide health products.

Therapeutic potentials of ginger for treatment of Multiple sclerosis: A review with emphasis on its immunomodulatory, anti-inflammatory and anti-oxidative properties

Multiple sclerosis (MS) is characterized by chronic inflammatory response-induced demyelination of the neurons and degeneration of the axons within the central nervous system (CNS). A complex network of immunopathological-, inflammatory- and oxidative parameters involve in the development and advancement of MS. The anti-inflammatory, immunomodulatory and anti-oxidative characteristics of the ginger and several of its components have been indicated in some of experimental and clinical investigations. The possible therapeutic potentials of ginger and its ingredients in the treatment of MS may exert mainly through the regulation of the Th1-, Th2-, Th9-, Th17-, Th22- and Treg cell-related immune responses, down-regulation of the B cell-related immune responses, modulation of the macrophages-related responses, modulation of the production of pro- and anti-inflammatory cytokines, down-regulation of the arachidonic acid-derived mediators, interfering with the toll like receptor-related signaling pathways, suppression of the inflammasomes, down-regulation of the oxidative stress, reduction of the adhesion molecules expression, and down-regulation of the expression of the chemokines and chemokine receptors. This review aimed to provide a comprehensive knowledge regarding the immunomodulatory-, anti-inflammatory and anti-oxidative properties of ginger and its components, and highlight novel insights into the possible therapeutic potentials of this plant for treatment of MS. The review encourages more investigations to consider the therapeutic potentials of ginger and its effective components for managing of MS.

Gingerol suppresses sepsis-induced acute kidney injury by modulating methylsulfonylmethane and dimethylamine production

Acute kidney injury (AKI) and metabolic dysfunction are critical complications in sepsis syndrome; however, their pathophysiological mechanisms remain poorly understood. Therefore, we evaluated whether the pharmacological properties of 6-gingerol (6G) and 10-gingerol (10G) could modulate AKI and metabolic disruption in a rat model of sepsis (faecal peritonitis). Animals from the sham and AKI groups were intraperitoneally injected with 6G or 10G (25 mg/kg). Septic AKI decreased creatinine clearance and renal antioxidant activity, but enhanced oxidative stress and the renal mRNA levels of tumour necrosis factor-α, interleukin-1β, and transforming growth factor-β. Both phenol compounds repaired kidney function through antioxidant activity related to decreased oxidative/nitrosative stress and proinflammatory cytokines. Metabolomics analysis indicated different metabolic profiles for the sham surgery group, caecal ligation and puncture model alone group, and sepsis groups treated with gingerols. ¹H nuclear magnetic resonance analysis detected important increases in urinary creatine, allantoin, and dimethylglycine levels in septic rats. However, dimethylamine and methylsulfonylmethane metabolites were more frequently detected in septic animals treated with 6G or 10G, and were associated with increased survival of septic animals. Gingerols attenuated septic AKI by decreasing renal disturbances, oxidative stress, and inflammatory response through a mechanism possibly correlated with increased production of dimethylamine and methylsulfonylmethane.

A novel method for the quantitation of gingerol glucuronides in human plasma or urine based on stable isotope dilution assays

The bio-active compounds of ginger (Zingiber officinale Roscoe), the gingerols, are gaining considerable attention due to their numerous beneficial health effects. In order to elucidate the physiological relevance of the ascribed effects their bioavailability has to be determined taking their metabolization into account. To quantitate in vivo generated [6]-, [8]- and [10]-gingerol glucuronides in human plasma and urine after ginger tea consumption, a simultaneous and direct liquid chromatography-tandem mass spectrometry method based on stable isotope dilution assays was established and validated. The respective references as well as the isotopically labeled substances were synthesized and characterized by mass spectrometry and NMR. Selective isolation of gingerol glucuronides from human plasma and urine by a mixed-phase anion-exchange SPE method led to recovery rates between 80.8 and 98.2%. LC-MS/MS analyses in selected reaction monitoring modus enabled a highly sensitive quantitation of gingerol glucuronides with LoQs between 3.9-9.8nmol/L in plasma and 39.3-161.1nmol/L in urine. The method precision in plasma and urine varied in the range±15%, whereas the intra-day accuracy in plasma and urine showed values between 78 and 122%. The developed method was then applied to a pilot study in which two volunteers consumed one liter ginger tea. Pharmacokinetic parameters like the maximum concentration (cmax), the time to reach cmax (tmax), area under the curve (AUC), elimination rate constant (kel) and elimination half-life (t1/2) were calculated from the concentration-time curve of each gingerol glucuronide. The obtained results will enable more detailed investigation of gingerol glucuronides as bioactives in their physiologically relevant concentrations.

Quantitation of Gingerols in Human Plasma by Newly Developed Stable Isotope Dilution Assays and Assessment of Their Immunomodulatory Potential

In a pilot study with two volunteers, the main pungent and bioactive ginger (Zingiber officinale Roscoe) compounds, the gingerols, were quantitated in human plasma after ginger tea consumption using a newly established HPLC-MS/MS(ESI) method on the basis of stable isotope dilution assays. Limits of quantitation for [6]-, [8]-, and [10]-gingerols were determined as 7.6, 3.1, and 4.0 nmol/L, respectively. The highest plasma concentrations of [6]-, [8]-, and [10]-gingerols (42.0, 5.3, and 4.8 nmol/L, respectively) were reached 30-60 min after ginger tea intake. Incubation of activated human T lymphocytes with gingerols increased the intracellular Ca(2+) concentration as well as the IFN-γ secretion by about 20-30%. This gingerol-induced increase of IFN-γ secretion could be blocked by the specific TRPV1 antagonist SB-366791. The results of the present study point to an interaction of gingerols with TRPV1 in activated T lymphocytes leading to an augmentation of IFN-γ secretion.