Gingerols and related analogues inhibit arachidonic acid-induced human platelet serotonin release and aggregation

The Clinical Research on Ginger (Zingiber officinale): Insights from ClinicalTrials.gov analysis

Ginger (Zingiber officinale) has a rich history of traditional medicinal use and has attracted a global interest in its health benefits. This study aims to provide insights into the clinical research landscape on ginger, focusing on its pharmacological effects and studied health-related outcomes. The study design involves systematic analysis of data from clinical trials available on ClinicalTrials.gov and discussion of findings in the context of the existing scientific knowledge. A comprehensive analysis of clinical trials registered on ClinicalTrials.gov related to ginger was first conducted, and the scientific background related to specific ginger clinical research avenues was further evaluated through PubMed searches. A variety of trial designs were identified, including treatment, prevention, and supportive care objectives. A total of 188 studies were identified on ClinicalTrials.gov, of which 89 met the inclusion criteria. Among the 89 trials, treatment objectives were predominant (47.2%), and dietary supplements (40.4%) and drugs (27%) were the most prevalent intervention types. These trials covered various health outcomes, such as antiemetic activity, analgesic function, effects on health-related quality of life, blood pressure variation, energy expenditure, and reduction in xerostomia. This study analysis provides a comprehensive overview of the clinical trials landscape on ginger, focusing on its broad spectrum of potential health benefits. While individual trials show promising results, a significant gap in the available data with a low reporting rate of final results is identified, underscoring the need for further research to establish conclusive evidence of ginger's therapeutic potentials.

Revisiting the therapeutic potential of gingerols against different pharmacological activities

The rhizomes of ginger have been in use in many forms of traditional and alternative medicines. Besides being employed as condiment and flavoring agent, it is used in the treatment of nausea, osteoarthritis, muscle pain, menstrual pain, chronic indigestion, Alzheimer's disease, and cancer. Ginger rhizome contains volatile oils, phenolic compounds and resins, and characterization studies showed that [6]-gingerol, [6]-shogaol, and [6]-paradol are reported to be the pharmacologically active components. Gingerol is a major chemical constituent found as volatile oil in the rhizomes of ginger. It has several medicinal benefits and used for the treatment of rheumatoid arthritis, nausea, cancer, and diabetes. Many studies have been carried out in various parts of the world to isolate and standardize gingerol for their use as a complementary medicine. The present review summarizes wide range of research studies on gingerol and its pharmacological roles in various metabolic diseases.

Preparation and Evaluation of 6-Gingerol Derivatives as Novel Antioxidants and Antiplatelet Agents

Ginger (Zingiber officinale) is widely used as a spice and a traditional medicine. Many bioactivities have been reported for its extracts and the isolated compounds, including cardiovascular protective effects. Different pathways were suggested to contribute to these effects, like the inhibition of platelet aggregation. In this study, we synthesised fourteen 6-gingerol derivatives, including eight new compounds, and studied their antiplatelet, COX-1 inhibitor, and antioxidant activities. In silico docking of selected compounds to h-COX-1 enzyme revealed favourable interactions. The investigated 6-gingerol derivatives were also characterised by in silico and experimental physicochemical and blood-brain barrier-related parameters for lead and preclinical candidate selection. 6-Shogaol (2) was identified as the best overall antiplatelet lead, along with compounds 3 and 11 and the new compound 17, which require formulation to optimize their water solubility. Compound 5 was identified as the most potent antioxidant that is also promising for use in the central nervous system (CNS).

Therapeutic Efficacy of a Formulation Prepared with Linum usitatissimum L., Plantago ovata Forssk., and Honey on Uncomplicated Pelvic Inflammatory Disease Analyzed with Machine Learning Techniques

A single-blind double-dummy randomized study was conducted in diagnosed patients (n = 66) to compare the efficacy of Linseeds (Linum usitatissimum L.), Psyllium (Plantago ovata Forssk.), and honey in uncomplicated pelvic inflammatory disease (uPID) with standard drugs using experimental and computational analysis. The pessary group received placebo capsules orally twice daily plus a per vaginum cotton pessary of powder from linseeds and psyllium seeds, each weighing 3 gm, with honey (5 mL) at bedtime. The standard group received 100 mg of doxycycline twice daily and 400 mg of metronidazole TID orally plus a placebo cotton pessary per vaginum at bedtime for 14 days. The primary outcomes were clinical features of uPID (vaginal discharge, lower abdominal pain (LAP), low backache (LBA), and pelvic tenderness. The secondary outcomes included leucocytes (WBCs) in vaginal discharge on saline microscopy and the SF-12 health questionnaire. In addition, we also classified both (pessary and standard) groups using machine learning models such as Decision Tree (DT), Random Forest (RF), Logistic Regression (LR), and AdaBoost (AB). The pessary group showed a higher percentage reduction than the standard group in abnormal vaginal discharge (87.05% vs. 77.94%), Visual Analogue Scale (VAS)-LAP (80.57% vs. 77.09%), VAS-LBA (74.19% vs. 68.54%), McCormack pain scale (McPS) score for pelvic tenderness (75.39% vs. 67.81%), WBC count of vaginal discharge (87.09% vs. 83.41%) and improvement in SF-12 HRQoL score (94.25% vs. 86.81%). Additionally, our DT 5-fold model achieved the maximum accuracy (61.80%) in the classification. We propose that the pessary group is cost-effective, safer, and more effective as standard drugs for treating uPID and improving the HRQoL of women. Aucubin, Plantamajoside, Herbacetin, secoisolariciresinol diglucoside, Secoisolariciresinol Monoglucoside, and other various natural bioactive molecules of psyllium and linseeds have beneficial effects as they possess anti-inflammatory, antioxidant, antimicrobial, and immunomodulatory properties. The anticipated research work is be a better alternative treatment for genital infections.

Impact of drying and extractions processes on the recovery of gingerols and shogaols, the main bioactive compounds of ginger

Ginger extracts have anti-inflammatory, antioxidant, antitumor, and antibacterial activities mainly due to gingerols and shogaols. Extract composition and functionality can be affected by drying and extraction processes. Alternative methods to obtain ginger extracts based on high contents of gingerols and shogaols have been reported. However, there were no studies that present a broad overview of how these methods affect the composition and functionalities of ginger extracts. Based on literature data from 2011 to 2022, this review shows how drying, extraction, and complementary processes (i.e., enzymatic, acidic, and carbonic maceration) affect the composition and bioactivity of the ginger extract. Lower temperature processes, including freeze-drying, cold ultrasound-, or enzyme-assisted extraction, lead to extracts richer in phenolics, gingerols, and antioxidant activity. On the other hand, acidic solvents or "hot" processes including microwave-drying, pressurized liquid, and microwave-assisted extraction can favor higher shogaols concentrations, which have higher antitumor, anti-inflammatory, and antimicrobial activities than the gingerols precursors. Thus, in this review, we analyzed and discussed the relation between ginger processing and their bioactive compounds, focusing especially on gingerols and shogaols, as well as the main processes that increase the content of 6-shogaol without compromising other phenolic compounds to produce highly functional extracts for future applications in the food packaging sector.

Synthesis and in vitro evaluation of natural drug loaded polymeric films for cardiovascular applications

Drug eluting stents (DES) can efficiently reduce the atherosclerosis and restenosis issues of coronary artery as compared to bare metal stents due to the presence of pharmaceutically active agent on their surface. Nevertheless, the arising safety concerns of DES such as delayed healing and late in stent restenosis and thrombus, has stirred the research efforts to improve the outcomes of the DES. In this connection, attention is being shifted from the use of synthetic drug to natural drug for DES. In the present work, natural compound loaded polymeric films were synthesized and their antioxidant and anticoagulation capabilities were assessed through in vitro testing. The potential of the drug loaded polymeric films to curb the production of free radicals was evaluated by carrying out antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The in vitro platelet adhesion was investigated through static platelet adhesion test while effect of synthesized films on intrinsic coagulation pathway was investigated through activated partially thromboplastin time (APTT). Moreover, to further evaluate the blood compatibility of the developed drug loaded films, in vitro hemolytic and anti-thrombolytic assays were carried out. The obtained results indicated that, incorporating herbal compounds such as ginger, magnolol and curcumin, in polymeric matrix (PVA) has significantly improved the blood compatibility of the polymeric films. Hence, it can be concluded that the synthesized drug loaded polymeric films have the potential capability to be used as a potential coating material for coating biomedical implants with good anticoagulation and antioxidant property to cater the cardiovascular issues such as atherosclerosis, restenosis and thrombus formation.

Medicinal chemistry inspired by ginger: exploring the chemical space around 6-gingerol

Ginger (Zingiber officinale Roscoe) has been used as a spice and as a traditional remedy since ancient times, especially in traditional Chinese medicine. It has been applied as a treatment for many diseases either alone or in combination with other remedies. Many studies were conducted on ginger and its constituents and a wide array of bioactivities were reported, e.g., antioxidant, anti-inflammatory, antiemetic, and anticancer activity. Most of these had been correlated to gingerols and shogaols, the most abundant secondary metabolites in ginger. This inspired several research groups to explore the biomedical value of the chemical space around these compounds, and many of their synthetic or semi-synthetic analogues have been prepared and studied for various bioactivities. Thanks to this, many valuable structure activity relationships have been revealed for such compounds. Herein, we provide a brief summary on the synthetic derivatization efforts that had so far been implemented on 6-gingerol, the main constituent of fresh ginger. This review covers 160 natural, semisynthetic, or synthetic 6-gingerol derivatives and their reported bioactivities.

Structure and reported bioactivities of semi-synthetic and synthetic 6-gingerol derivatives.

Herbal Medicine for Pain Management: Efficacy and Drug Interactions

Complementary and alternative medicines such as herbal medicines are not currently part of the conventional medical system. As the popularity of and global market for herbal medicine grows among all age groups, with supporting scientific data and clinical trials, specific alternative treatments such as herbal medicine can be reclassified as a practice of conventional medicine. One of the most common conditions for which adults use herbal medicine is pain. However, herbal medicines carry safety concerns and may impact the efficacy of conventional therapies. Unfortunately, mechanisms of action are poorly understood, and their use is unregulated and often underreported to medical professionals. This review aims to compile common and available herbal medicines which can be used as an alternative to or in combination with conventional pain management approaches. Efficacy and safety are assessed through clinical studies on pain relief. Ensuing herb–drug interactions such as cytochrome modulation, additive and synergistic effects, and contraindications are discussed. While self-management has been recognized as part of the overall treatment strategy for patients suffering from chronic pain, it is important for practitioners to be able to also optimize and integrate herbal medicine and, if warranted, other complementary and alternative medicines into their care.

6-Shogaol Protects Human Melanocytes against Oxidative Stress through Activation of the Nrf2-Antioxidant Response Element Signaling Pathway

Skin is a major target of oxidative stress. Increasing evidence suggests that oxidative stress is the cause of melanocyte disappearance in vitiligo, which is an acquired pigmentary skin disorder characterized by patches of skin that have lost pigmentation. New herbal extracts with antioxidant activity are therefore being studied. 6-Shogaol (6-SG), an active compound from ginger, is capable of attenuating oxidative stress-induced ageing and neurotoxicity. Subsequently, to investigate whether 6-SG could protect melanocytes from oxidative stress, cultured human primary epidermal melanocytes (HEMn-MPs) were treated with hydrogen peroxide (H₂O₂) in the presence or absence of 6-SG. The 6-SG exhibited protective effects against H₂O₂-induced cell death by reducing oxidative stress. In addition, the 6-SG treatment activated the Nrf2-antioxidant response element signaling pathway by upregulating the mRNA expression of the antioxidant enzyme heme oxygenase 1 (HO-1), and protein expression of Nrf2, NAD(P)H: quinine oxidoreductase 1 (Nqo1), and HO-1. Furthermore, the 6-SG also displayed protective effects on melanocytes against Rhododendrol-induced oxidative stress. We concluded that 6-SG protects melanocytes against oxidative stress in vitro, and its protective effect is associated with the activation of the Nrf2-antioxidant response element signaling pathway. 6-SG, therefore, has potential for use in the prevention of melanocyte loss in the early stages of vitiligo or other pigmentary disorders.

Voltammetric and spectroscopic determination of polyphenols and antioxidants in ginger (Zingiber officinale Roscoe)

Ginger (Zingiber officinale) is widely consumed as an important spice or a common condiment in food and beverages. This study focuses on the determination of pungent and bioactive components in ginger and their antioxidant activity using voltammetric and spectroscopic methods. Gas chromatography-mass spectroscopy analysis revealed that the major components of the pungent compounds were zingerone, shogaols, gingerols, paradols, wikstromol, and carinol. Using spectroscopic methods, the antioxidant capacity of ginger aqueous extract was found to be 16.0 μmol gallic acid equivalent (GAE) per gram of ginger extract, and the total phenolic and flavonoid content was estimated to be 7.8 mg GAE/g ginger extract and 15.4 mg Quercetin equivalent (QE) per gram of ginger extract, respectively. Electroanalytical quantification estimated the antioxidant capacity of the ginger infusion to be 23.5 μmol GAE/g ginger extract, which is slightly higher than that estimated using chemical assay. The results may provide useful information for the development of ginger processing and utilization as a flavoring agent, and for our understanding of ginger as a source of natural antioxidants.

6-Gingerol, an active pungent component of ginger, inhibits L-type Ca2+ current, contractility, and Ca2+ transients in isolated rat ventricular myocytes

Ginger has been widely used as a flavor, food, and traditional medicine for centuries. 6-Gingerol (6-Gin) is the active components of ginger and offers some beneficial effects on cardiovascular diseases. Here, the effects of 6-Gin on L-type Ca2+ current (ICa-L), contractility, and the Ca2+ transients of rat cardiomyocytes, were investigated via patch-clamp technique and the Ion Optix system. The 6-Gin decreased the ICa-L of normal and ischemic ventricular myocytes by 58.17 ± 1.05% and 55.22 ± 1.34%, respectively. 6-Gin decreased ICa-L in a concentration-dependent manner with a half-maximal inhibitory concentration (IC50) of 31.25 μmol/L. At 300 μmol/L, 6-Gin reduced the cell shortening by 48.87 ± 5.44% and the transients by 42.5 ± 9.79%. The results indicate that the molecular mechanisms underlying the cardio-protective effects of 6-Gin may because of a decreasing of intracellular Ca2+ via the inhibition of ICa-L and contractility in rat cardiomyocytes.

Combining and Using the Utrecht Method and the Analytic Hierarchy Process to Facilitate Professional and Ethical Deliberation and Decision Making in Complementary and Alternative Medicine: A Case Study among a Panel of Stakeholders

Background

In daily practice, healthcare practitioners face many challenges in ethical and professional decision making. Currently, little is known on the ethical and professional deliberations and weighing benefits against risks in daily complementary and alternative medicine (CAM) practice. The aim of this study was to combine the Utrecht method and the Analytic Hierarchy Process (AHP) in deliberations, weighing benefits against risks of using ginger for a pregnant woman suffering nausea and vomiting of pregnancy (NVP) along with other comorbidities.

Methods

A hypothetical case was constructed using the twelve tips for constructing dilemma case-based assessment. Three CAM practitioners, two physicians, three pharmacists, and two patients were recruited, and the Utrecht and the AHP methods were combined and used to deliberate and weigh benefits against risks of using ginger for the presented case.

Results

Responses from the ten panelists were obtained. Priority ratings showed significantly higher scores (p-value < 0.001) for alleviating symptoms of NVP (30.7%  ± 16.6%) compared to other potential benefits. Increasing the risk of bleeding was given significantly higher (p-value < 0.0001) weight scores (24.7%  ± 13.5%) than other potential side effects. Potential risk of spontaneous abortion and risk of impairment of fetal development were given higher (p-value < 0.001) weight scores than risk of fetal hypoglycemia. When benefits were compared against side effects and risks to the fetus and pregnancy, potential benefits were given higher (p-value < 0.001) weight scores (72.3%  ± 5.2%).

Conclusions

Considering the anticipated benefits and risks, a shared decision was made to use ginger in the case presented. The woman should also be informed of the potential side effects and risks of using ginger. The use of this combined method might promote openness and transparency in making shared decisions for healthcare providers and patients.

Rapid ultrasonic and microwave-assisted micellar extraction of zingiberone, shogaol and gingerols from gingers using biosurfactants

Two kinds of extraction methods ultrasonic-assisted micellar extraction (UAME) and microwave-assisted micellar extraction (MAME) coupled with ultra-high performance liquid chromatography with ultraviolet detector (UHPLC-UV) were developed and evaluated for extraction and determination of zingerone, 6-gingerol, 8-gingerol, 6-shogaol and 10-gingerol in Rhizoma Zingiberis and Rhizoma Zingiberis Preparata. A biosurfactant, hyodeoxycholic acid sodium salt, was used in micellar extraction. Several experimental parameters were studied separately by a univariate method. The result indicated that the MAME was more efficient than UAME. The optimal conditions of MAME were as follows: 100mM of hyodeoxycholic acid sodium salt was used as surfactant, the irradiation time was set at 10s and the extraction temperature was set at 60°C. The validation results indicated that the limits of detection were in the range of 3.80-8.11ng/mL. The average recoveries were in the range of 87.32-103.12% for the two samples at two spiking levels. Compared with other reported methods, the proposed MAME-UHPLC-UV method was more effective, quicker (10s) and more eco-friendly.

The Analgesic and Anti-Inflammatory Activity of Linum usitatissimum in Balb/c Mice

Linum usitatissimum L is traditionally used for relief of pain and inflammation. In this study, the analgesic and anti-inflammatory effects of this plant were evaluated. Xylene test was used for anti-inflammatory evaluation in which 48 mice were randomly designated into 6 groups of 8 each including: control, dexamethasone as positive control (15 mg/kg), and experimental groups (42, 85, 170, and 340 mg/kg, respectively). For analgesic evaluation, 192 mice were randomly designated into 4 sets of 6 groups of 8 mice, including control, morphine as positive control, morphine plus naloxone, experimental groups (200 and 500 mg/kg extract), and extract along with naloxone group, which received 500 mg/kg. The analgesic activities were evaluated at 5, 15, 30, and 60 minutes, respectively, in each set. Both doses showed analgesic activity, the 200 mg/kg possessed higher effects (P < .05). Naloxone reduced a section of its effect (P < .001). The 170 mg/kg dose of the extract showed anti-inflammatory activity (P < .05). The extract had phenolic, flavonoid, and flavonol compounds with antioxidant activity. Linum usitatissimum L dose dependently had analgesic activity partially like morphine and might be used as analgesic and anti-inflammatory agent.

Which potential harms and benefits of using ginger in the management of nausea and vomiting of pregnancy should be addressed? a consensual study among pregnant women and gynecologists

BACKGROUND

Nausea and vomiting of pregnancy (NVP) affect approximately 80-90% of the pregnant women. Ginger (Zingiber officinale Roscoe) is the most widely used herbal therapy in the management of NVP. Like conventional therapies, herbal therapies have potential harms and benefits that patients need to be informed about in order to develop their therapy preferences. The aim of this study was to achieve consensus among women who suffered NVP and physicians often consulted by pregnant women on a core list of potential harms and benefits of using ginger to manage NVP to be addressed during clinical consultations.

METHODS

In this study, the Delphi technique was used to achieve consensus on a core list of important harms and benefits of using ginger in the management of NVP to be addressed during the clinical consultation. A Delphi process was followed in two panels in parallel sessions. One panel was composed of 50 gynecologists and other physicians who are often consulted by pregnant women suffering NVP and the other panel was composed of 50 women who suffered NVP.

RESULTS

Consensus was achieved on 21 (75%) of the 28 potential harms presented to the panelists. Panelists agreed that potential harms of the anticoagulant effects of ginger, risk with other co-morbidities, and risk of potential allergic reactions are important to address during the clinical consultation. Of the 14 potential benefits presented to the panelists in both panels, consensus was achieved on 13 (92.9%). Partial consensus on 7 potential harms and 1 potential benefit was achieved in both panels.

CONCLUSIONS

Addressing important potential harms and benefits of using ginger for the management of NVP during the clinical consultations is important in promoting congruence and reducing patient dissatisfaction in clinical practice. Consensus was achieved on a core list of important harms and benefits of using ginger for the management of NVP to be addressed during the clinical consultations by a panel of women and a panel of physicians. Further studies are still needed to investigate what is being addressed during clinical consultations.

Electrochemical detection and quantification of gingerol species in ginger (Zingiber officinale) using multiwalled carbon nanotube modified electrodes

We demonstrate the potential of electrochemical detection for the analysis of the 'strength' of ginger in ginger sample. This facile and fast detection method is aimed at the quality control in food industry. Specifically, we report adsorptive stripping voltammetry (AdsSV) as a technique for detection of gingerol compounds, the pungent components of ginger rhizome. Among the gingerols, 6-gingerol is the most abundant and is chosen as a model to characterise the behaviour of a wider range of related compounds. Multiwalled carbon nanotube modified basal plane pyrolytic graphite electrodes (MWCNT-BPPG electrode) are employed to enhance the sensitivity of the measurement. A linearity range from 1 μM to 50 μM with limit of detection of 0.21 μM and limit of quantification of 0.71 μM is obtained. Further, the simple and rapid extraction procedure by simply vortexing the ginger sample with ethanol is developed for extraction of gingerol related species.

Changes in antioxidant and antibacterial activities as well as phytochemical constituents associated with ginger storage and polyphenol oxidase activity

Background

Herbal materials should be stored at optimal conditions in order to retain their nutritional quality. Proper storage has a significant impact on the quality of the herbs and spices.

Methods

The effects of storage temperature (5 and 15 °C) and time (4 and 8 months) on the phytochemical constituents associated with the antioxidant and antibacterial activities of ginger varieties (Halia bentong and Halia bara) were evaluated to determine the optimal storage conditions for ginger rhizomes. Total flavonoid content (TFC) and Total phenolic content (TPC) were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6-gingerol and 6-shogaol were identified by ultra-high performance liquid chromatography. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for evaluation of antioxidant activities. An antibacterial property of ginger varieties was evaluated using well diffusion method.

Results

Dry matter, TPC, TFC and individual phenolics and flavonoids content, 6-gingerol and 6-shogaol content noticeably decreased at 5 and 15 °C during the storage times from 4 to 8 months. Highest content of flavonoids, phenolic acids, 6-gingerol, and 6-shogaol was observed in fresh samples followed by rhizomes stored at 5 °C for 4 months. Storage at 15 °C for 4 months reduced the phytochemical content significantly. Cinnamic acid and tannic acid were not detected in those variety stored at 15 °C for 4 and 8 months. Polyphenol oxidase (PPO) activity was associated significantly with storage time and temperature. Highest and lowest PPO activity was observed in stored and fresh rhizomes respectively. Antioxidant and antimicrobial activities gradually declined with the increase of storage temperature (from 5 to 15 °C) and duration (from 4 to 8 months) in both the varieties. Freshly harvested Halia bara variety had higher antioxidant and antibacterial activity compared to the Halia bentong variety.

Conclusions

Halia bara exhibited valuable phytochemical content and antioxidant and antibacterial activities at higher levels compared to that exhibited by Halia bentong rhizomes. In general, storage of Malaysian ginger varieties at temperature of 5 °C is recommended and the storage time should be not more than 4 months. This storage condition will provide greater stability to the concentration of the phytochemical constituents more similar to the fresh material. 

Dietary Supplementation of Ginger and Turmeric Rhizomes Modulates Platelets Ectonucleotidase and Adenosine Deaminase Activities in Normotensive and Hypertensive Rats

Hypertension is associated with platelet alterations that could contribute to the development of cardiovascular complications. Several studies have reported antiplatelet aggregation properties of ginger (Zingiber officinale) and turmeric (Curcuma longa) with limited scientific basis. Hence, this study assessed the effect of dietary supplementation of these rhizomes on platelet ectonucleotidase and adenosine deaminase (ADA) activities in Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME) induced hypertensive rats. Animals were divided into seven groups (n = 10): normotensive control rats; induced (l-NAME hypertensive) rats; hypertensive rats treated with atenolol (10 mg/kg/day); normotensive and hypertensive rats treated with 4% supplementation of turmeric or ginger, respectively. After 14 days of pre-treatment, the animals were induced with hypertension by oral administration of l-NAME (40 mg/kg/day). The results revealed a significant (p < 0.05) increase in platelet ADA activity and ATP hydrolysis with a concomitant decrease in ADP and AMP hydrolysis of l-NAME hypertensive rats when compared with the control. However, dietary supplementation with turmeric or ginger efficiently prevented these alterations by modulating the hydrolysis of ATP, ADP and AMP with a concomitant decrease in ADA activity. Thus, these activities could suggest some possible mechanism of the rhizomes against hypertension-derived complications associated to platelet hyperactivity. Copyright © 2016 John Wiley & Sons, Ltd.

Variation of the Phytochemical Constituents and Antioxidant Activities of Zingiber officinale var. rubrum Theilade Associated with Different Drying Methods and Polyphenol Oxidase Activity

The effects of different drying methods (freeze drying, vacuum oven drying, and shade drying) on the phytochemical constituents associated with the antioxidant activities of Z. officinale var. rubrum Theilade were evaluated to determine the optimal drying process for these rhizomes. Total flavonoid content (TFC), total phenolic content (TPC), and polyphenol oxidase (PPO) activity were measured using the spectrophotometric method. Individual phenolic acids and flavonoids, 6- and 8-gingerol and shogaol were identified by ultra-high performance liquid chromatography method. Ferric reducing antioxidant potential (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays were used for the evaluation of antioxidant activities. The highest reduction in moisture content was observed after freeze drying (82.97%), followed by vacuum oven drying (80.43%) and shade drying (72.65%). The highest TPC, TFC, and 6- and 8-shogaol contents were observed in samples dried by the vacuum oven drying method compared to other drying methods. The highest content of 6- and 8-gingerol was observed after freeze drying, followed by vacuum oven drying and shade drying methods. Fresh samples had the highest PPO activity and lowest content of flavonoid and phenolic acid compounds compared to dried samples. Rhizomes dried by the vacuum oven drying method represent the highest DPPH (52.9%) and FRAP activities (566.5 μM of Fe (II)/g DM), followed by freeze drying (48.3% and 527.1 μM of Fe (II)/g DM, respectively) and shade drying methods (37.64% and 471.8 μM of Fe (II)/g DM, respectively) with IC50 values of 27.2, 29.1, and 34.8 μg/mL, respectively. Negative and significant correlations were observed between PPO and antioxidant activity of rhizomes. Vacuum oven dried rhizomes can be utilized as an ingredient for the development of value-added food products as they contain high contents of phytochemicals with valuable antioxidant potential.

Medicinal Plants with Antiplatelet Activity

Blood platelets play an essential role in the hemostasis and wound-healing processes. However, platelet hyperactivity is associated to the development and the complications of several cardiovascular diseases. In this sense, the search for potent and safer antiplatelet agents is of great interest. This article provides an overview of experimental studies performed on medicinal plants with antiplatelet activity available through literature with particular emphasis on the bioactive constituents, the parts used, and the various platelet signaling pathways modulated by medicinal plants. From this review, it was suggested that medicinal plants with antiplatelet activity mainly belong to the family of Asteraceae, Rutaceae, Fabaceae, Lamiaceae, Zygophyllaceae, Rhamnaceae, Liliaceae, and Zingiberaceae. The antiplatelet effect is attributed to the presence of bioactive compounds such as polyphenols, flavonoids, coumarins, terpenoids, and other substances which correct platelet abnormalities by interfering with different platelet signalization pathways including inhibition of the ADP pathway, suppression of TXA2 formation, reduction of intracellular Ca(2+) mobilization, and phosphoinositide breakdown, among others. The identification and/or structure modification of the plant constituents and the understanding of their action mechanisms will be helpful in the development of new antiplatelet agents based on medicinal plants which could contribute to the prevention of thromboembolic-related disorders by inhibiting platelet aggregation. Copyright © 2016 John Wiley & Sons, Ltd.

Medicinal Herbals with Antiplatelet Properties Benefit in Coronary Atherothrombotic Diseases

Coronary atherothrombotic diseases such as coronary artery disease, peripheral vascular disease, cerebrovascular disease, and heart failure are the serious concerns of the thrombus formed in blood vessels. Anticoagulant and antiplatelet drugs are the cornerstones of the management of these diseases. To prevent the recurrence of these diseases, double antiplatelet drugs such as aspirin and clopidogrel has been the standard management in most hospitals. However, aspirin resistance and clopidogrel inefficient effects due to noncompliance with double drugs regimen can cause a sinister effect on patients. Medicinal plants serve as a greater resource for new medication and their potential currently became a topic of interest to the researchers all over the world. Traditionally, certain herbs have been used as a treatment for heart diseases but have been investigated for their antiplatelet properties. This current review explained few traditional antithrombotic herbals and their antiplatelet properties in vitro and in vivo and this is to be deeply discussed in further research.

Gingerol and Its Role in Chronic Diseases

Since antiquity, ginger or Zingiber officinale, has been used by humans for medicinal purposes and as spice condiments to enhance flavor in cooking. Ginger contains many phenolic compounds such as gingerol, shogaol and paradol that exhibit antioxidant, anti-tumor and anti-inflammatory properties. The role of ginger and its constituents in ameliorating diseases has been the focus of study in the past two decades by many researchers who provide strong scientific evidence of its health benefit. This review discusses research findings and works devoted to gingerols, the major pungent constituent of ginger, in modulating and targeting signaling pathways with subsequent changes that ameliorate, reverse or prevent chronic diseases in human studies and animal models. The physical, chemical and biological properties of gingerols are also described. The use of ginger and especially gingerols as medicinal food derivative appears to be safe in treating or preventing chronic diseases which will benefit the common population, clinicians, patients, researchers, students and industrialists.

The Effect of Ginger (Zingiber officinale) on Platelet Aggregation: A Systematic Literature Review

BACKGROUND

The potential effect of ginger on platelet aggregation is a widely-cited concern both within the published literature and to clinicians; however, there has been no systematic appraisal of the evidence to date.

METHODS

Using the PRISMA guidelines, we systematically reviewed the results of clinical and observational trials regarding the effect of ginger on platelet aggregation in adults compared to either placebo or baseline data. Studies included in this review stipulated the independent variable was a ginger preparation or isolated ginger compound, and used measures of platelet aggregation as the primary outcome.

RESULTS

Ten studies were included, comprising eight clinical trials and two observational studies. Of the eight clinical trials, four reported that ginger reduced platelet aggregation, while the remaining four reported no effect. The two observational studies also reported mixed findings.

DISCUSSION

Many of the studies appraised for this review had moderate risks of bias. Methodology varied considerably between studies, notably the timeframe studied, dose of ginger used, and the characteristics of subjects recruited (e.g. healthy vs. patients with chronic diseases).

CONCLUSION

The evidence that ginger affects platelet aggregation and coagulation is equivocal and further study is needed to definitively address this question.

Commonly Used Dietary Supplements on Coagulation Function during Surgery

BACKGROUND

Patients who undergo surgery appear to use dietary supplements significantly more frequently than the general population. Because they contain pharmacologically active compounds, dietary supplements may affect coagulation and platelet function during the perioperative period through direct effects, pharmacodynamic interactions, and pharmacokinetic interactions. However, in this regard, limited studies have been conducted that address the pharmacological interactions of dietary supplements. To avoid possible bleeding risks during surgery, information of potential complications of dietary supplements during perioperative management is important for physicians.

METHODS

Through a systematic database search of all available years, articles were identified in this review if they included dietary supplements and coagulation/platelet function, while special attention was paid to studies published after 1990.

RESULTS

Safety concerns are reported in commercially available dietary supplements. Effects of the most commonly used natural products on blood coagulation and platelet function are systematically reviewed, including 11 herbal medicines (echinacea, ephedra, garlic, ginger, ginkgo, ginseng, green tea, kava, saw palmetto, St John's wort, and valerian) and 4 other dietary supplements (coenzyme Q₁₀, glucosamine and chondroitin sulfate, fish oil, and vitamins). Bleeding risks of garlic, ginkgo, ginseng, green tea, saw palmetto, St John's wort, and fish oil are reported. Cardiovascular instability was observed with ephedra, ginseng, and kava. Pharmacodynamic and pharmacokinetic interactions between dietary supplements and drugs used in the perioperative period are discussed.

CONCLUSIONS

To prevent potential problems associated with the use of dietary supplements, physicians should be familiar with the perioperative effects of commonly used dietary supplements. Since the effects of dietary supplements on coagulation and platelet function are difficult to predict, it is prudent to advise their discontinuation before surgery.

Pilot clinical study of the effects of ginger root extract on eicosanoids in colonic mucosa of subjects at increased risk for colorectal cancer

Colorectal cancer (CRC) remains a significant cause of mortality. Inhibitors of cyclooxygenase (COX) and thus prostaglandin E2, are promising CRC preventives, but have significant toxicities. Ginger has been shown to inhibit COX, to decrease the incidence and multiplicity of adenomas, and decrease PGE2 concentrations in subjects at normal risk for CRC. This study was conducted to determine the effects of 2.0 g/d of ginger given orally on the levels of PGE2, leukotriene B4 (LTB4), 13-hydroxy-octadecadienoic acids, and 5-, 12-, & 15-hydroxyeicosatetraenoic acid, in the colonic mucosa of subjects at increased risk for CRC. We randomized 20 subjects to 2.0 g/d ginger or placebo for 28 d. At baseline and Day 28, a flexible sigmoidoscopy was used to obtain colon biopsies. A liquid chromatography mass spectrometry method was used to determine eicosanoid levels in the biopsies, and levels were expressed per amount of protein or free arachidonic acid (AA). There was a significant decrease in AA between baseline and Day 28 (P = 0.05) and significant increase in LTB4 (P = 0.04) when normalized to protein, in subjects treated with ginger versus placebo. No other changes in eicosanoids were observed. There was no difference between the groups in total adverse events (AE; P = 0.06). Ginger lacks the ability to decrease eicosanoid levels in people at increased risk for CRC. Ginger did appear to be both tolerable and safe; and could have chemopreventive effects through other mechanisms. Further investigation should focus on other markers of CRC risk in those at increased CRC risk.

Optimization protocol for the extraction of 6-gingerol and 6-shogaol from Zingiber officinale var. rubrum Theilade and improving antioxidant and anticancer activity using response surface methodology

BACKGROUND

Analysis and extraction of plant matrices are important processes for the development, modernization, and quality control of herbal formulations. Response surface methodology is a collection of statistical and mathematical techniques that are used to optimize the range of variables in various experimental processes to reduce the number of experimental runs, cost , and time, compared to other methods.

METHODS

Response surface methodology was applied for optimizing reflux extraction conditions for achieving high 6-gingerol and 6-shogaol contents, and high antioxidant activity in Zingiber officinale var. rubrum Theilade . The two-factor central composite design was employed to determine the effects of two independent variables, namely extraction temperature (X1: 50-80 °C) and time (X2: 2-4 h), on the properties of the extracts. The 6-gingerol and 6-shogaol contents were measured using ultra-performance liquid chromatography. The antioxidant activity of the rhizome extracts was determined by means of the 1,1-diphenyl-2-picrylhydrazyl assay. Anticancer activity of optimized extracts against HeLa cancer cell lines was measured using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay.

RESULTS

Increasing the extraction temperature and time induced significant response of the variables. The optimum extraction condition for all responses was at 76.9 °C for 3.4 h. Under the optimum condition, the corresponding predicted response values for 6-gingerol, 6-shogaol, and the antioxidant activity were 2.89 mg/g DW, 1.85 mg/g DW, and 84.3%, respectively. 6-gingerol and 6-shogaol were extracted under optimized condition to check the viability of the models. The values were 2.92 and 1.88 mg/g DW, and 84.0% for 6-gingerol, 6-shogaol, and the antioxidant activity respectively. The experimental values agreed with those predicted, thus indicating suitability of the models employed and the success of RSM in optimizing the extraction condition. With optimizing of reflux extraction anticancer activity of extracts against HeLa cancer cells enhanced about 16.8%. The half inhibition concentration (IC50) value of optimized and unoptimized extract was found at concentration of 20.9 and 38.4 μg/mL respectively. Optimized extract showed more distinct anticancer activities against HeLa cancer cells in a concentration of 40 μg/mL (P < 0.01) without toxicity to normal cells.

CONCLUSIONS

The results indicated that the pharmaceutical quality of ginger could be improved significantly by optimizing of extraction process using response surface methodology.

Protective effects of the standardized extract of Zingiber officinale on myocardium against isoproterenol-induced biochemical and histopathological alterations in rats

CONTEXT

Ginger [Zingiber officinale Roscoe. (Zingiberaceae)] has been universally used as a spice as well as for its health benefits.

OBJECTIVE

The present study evaluates the protective effect of the standardized extract of ginger against isoproterenol (ISO)-induced myocardial infarction (MI) in rats.

MATERIALS AND METHODS

Wistar rats were pretreated orally with three doses of standardized ginger extract (100, 200, and 400 mg/kg of body weight) or propranolol (5 mg/mL) for 28 d prior to ISO (85 mg/kg) induced MI in two doses on days 29 and 30. The rats were sacrificed 48 h after the first induction; serum and hearts were collected for biochemical and histopathological analysis.

RESULTS

Gingerols and shogaols were identified and quantitatively analyzed in the extracts using validated reversed phase HPLC methods. Pretreatment with ginger extract at 400 mg/kg showed a significant decrease (p < 0.05) in all the cardiac enzyme activities, i.e., cardiac troponin I (cTnI) (0.57 ng/mL), creatine kinase MB isoenzyme (CK-MB) (10.34 pg/mL), lactate dehydrogenase (LDH) (115.22 U/L), alanine transaminase (ALT) (15.79 U/L), and aspartate transaminase (AST) (46.72 U/L) when compared with ISO-control rats. There were significant rises (p < 0.05) in the activity of glutathione peroxide (GPx) (53.16 U/L), catalase (CAT) (210.41 U/L), and superoxide dismutase (SOD) (280.89 U/mL) of the pretreated rats when compared with the ISO-control. Histopathological examination showed an improvement in membrane cell integrity in pretreated rats compared with untreated rats.

CONCLUSION

The ethanol extract of ginger exhibited cardioprotective potential in treating myocardial injury following ISO administration.

Synthesis of analogues of gingerol and shogaol, the active pungent principles from the rhizomes of Zingiber officinale and evaluation of their anti-platelet aggregation effects

The present study was aimed at discovering novel biologically active compounds based on the skeletons of gingerol and shogaol, the pungent principles from the rhizomes of Zingiber officinale. Therefore, eight groups of analogues were synthesized and examined for their inhibitory activities of platelet aggregation induced by arachidonic acid, collagen, platelet activating factor, and thrombin. Among the tested compounds, [6]-paradol (5b) exhibited the most significant anti-platelet aggregation activity. It was the most potent candidate, which could be used in further investigation to explore new drug leads.

Enzyme-assisted extraction of bioactive compounds from ginger (Zingiber officinale Roscoe)

Ginger (Zingiber officinale R.) is a popular spice used in various foods and beverages. 6-Gingerol is the major bioactive constituent responsible for the antiinflammatory, antitumour and antioxidant activities of ginger. The effect of application of α-amylase, viscozyme, cellulase, protease and pectinase enzymes to ginger on the oleoresin yield and 6-gingerol content has been investigated. Pre-treatment of ginger with α-amylase or viscozyme followed by extraction with acetone afforded higher yield of oleoresin (20%±0.5) and gingerol (12.2%±0.4) compared to control (15%±0.6 oleoresin, 6.4%±0.4 gingerol). Extraction of ginger pre-treated with enzymes followed by extraction with ethanol provided higher yield of gingerol (6.2-6.3%) than the control (5.5%) with comparable yields of the oleoresin (31-32%). Also, ethanol extract of cellulase pre-treated ginger had the maximum polyphenol content (37.5 mg/g). Apart from 6-gingerol, 6-paradol along with 6- and 8-methyl shogaols were the other important bio-active constituents in the oleoresin from cellulase-treated ginger.

Functional ginger extracts from supercritical fluid carbon dioxide extraction via in vitro and in vivo assays: antioxidation, antimicroorganism, and mice xenografts models

Supercritical fluid carbon dioxide extraction technology was developed to gain the active components from a Taiwan native plant, Zingiber officinale (ginger). We studied the biological effects of ginger extracts via multiple assays and demonstrated the biofunctions in each platform. Investigations of ginger extracts indicated antioxidative properties in dose-dependant manners on radical scavenging activities, reducing powers and metal chelating powers. We found that ginger extracts processed moderate scavenging values, middle metal chelating levels, and slight ferric reducing powers. The antibacterial susceptibility of ginger extracts on Staphylococcus aureus, Streptococcus sobrinus, S. mutans, and Escherichia coli was determined with the broth microdilution method technique. The ginger extracts had operative antimicroorganism potentials against both Gram-positive and Gram-negative bacteria. We further discovered the strong inhibitions of ginger extracts on lethal carcinogenic melanoma through in vivo xenograft model. To sum up, the data confirmed the possible applications as medical cosmetology agents, pharmaceutical antibiotics, and food supplements.

Enhancements of skin cell proliferations and migrations via 6-dehydrogingerdione

Human skin protects the body from mechanical and chemical damages, and skin wound healing is a costly procedure and worldwide issue. A Zingiber officinale compound, 6-dehydrogingerdione (6-DG), is presented as a novel biofunctional healing agent for human skin wound repair. The effectiveness on cell growth/migration, growth factor, collagen amount, and enzymatic activity was assessed. 6-DG treatment accelerated cellular proliferation and migration dose-dependently. Enzyme-linked immunosorbent assay (ELISA) showed that 6-DG brought about higher growth factor productions on transforming growth factor-β (TGF-β), platelet-derived growth factor-αβ (PDGF-αβ), and vascular endothelial growth factors (VEGF). Under phorbol 12-myristate 13-acetate (PMA) incubation, 6-DG increased fibroblast collagen yield obviously, reduced matrix metalloproteinase-1 (MMP-1) protein expression, and recovered tissue inhibitor of metalloproteinase-1 (TIMP-1) secretion. 6-DG also blocked the mitogen-activated protein kinase (MAPK) pathway by suppressing c-Jun protein levels and extracellular signal-regulated kinases (ERK) phosphorylation in fibroblasts. From all of the above, 6-DG has potential to be a novel agent for human skin repair.

6-shogaol-rich extract from ginger up-regulates the antioxidant defense systems in cells and mice

The rhizome of ginger (Zingiber officinale Roscoe) is known to have several bioactive compounds including gingerols and shogaols which possess beneficial health properties such as anti-inflammatory and chemopreventive effects. Based on recent observations that 6-shogaol may have more potent bioactivity than 6-gingerol, we obtained a 6-shogaol-rich extract from ginger and examined its effects on the nuclear factor E2-related factor2 (Nrf2)/antioxidant response element (ARE) pathway in vitro and in vivo. 6-Shogaol-rich extract was produced by extracting ginger powder with 95% ethanol at 80 °C after drying at 80 °C (GEE8080). GEE8080 contained over 6-fold more 6-shogaol compared to the room temperature extract (GEE80RT). In HepG2 cells, GEE8080 displayed much stronger inductions of ARE-reporter gene activity and Nrf2 expression than GEE80RT. GEE8080 stimulated phosphorylations of mitogen-activated protein kinases (MAPKs) such as ERK, JNK, and p38. Moreover, the GEE8080-induced expressions of Nrf2 and HO-1 were attenuated by treatments of SB202190 (a p38 specific inhibitor) and LY294002 (an Akt specific inhibitor). In a mouse model, the GEE8080 decreased the diethylnitrosamine (DEN)-mediated elevations of serum aspartate transaminase and alanine transaminase as well as the DEN-induced hepatic lipid peroxidation. Inductions of Nrf2 and HO-1 by GEE8080 were also confirmed in the mice. In addition, the administration of GEE8080 to the mice also restored the DEN-reduced activity and protein expression of hepatic antioxidant enzymes such as superoxide dismutase, glutathione peroxidase and catalase. In conclusion, GEE8080, a 6-shogaol-rich ginger extract, may enhance antioxidant defense mechanism through the induction of Nrf2 and HO-1 regulated by p38 MAPK and PI3k/Akt pathway in vitro and in vivo.

Attenuation of liver pro-inflammatory responses by Zingiber officinale via inhibition of NF-kappa B activation in high-fat diet-fed rats

The aim of this study was to investigate whether treatment with a ginger (Zingiber officinale) extract of high-fat diet (HFD)-fed rats suppresses Nuclear factor-kappa B (NF-κB)-driven hepatic inflammation and to subsequently explore the molecular mechanisms in vitro. Adult male Sprague-Dawley rats were treated with an ethanolic extract of Zingiber officinale (400 mg/kg) along with a HFD for 6 weeks. Hepatic cytokine mRNA levels, cytokine protein levels and NF-κB activation were measured by real-time PCR, Western blot and an NF-κB nuclear translocation assay, respectively. In vitro, cell culture studies were carried out in human hepatocyte (HuH-7) cells by treatment with Zingiber officinale (100 μg/mL) for 24 hr prior to interleukin-1β (IL-1β, 8 ng/mL)-induced inflammation. We showed that Zingiber officinale treatment decreased cytokine gene TNFα and IL-6 expression in HFD-fed rats, which was associated with suppression of NF-κB activation. In vitro, Zingiber officinale treatment decreased NF-κB-target inflammatory gene expression of IL-6, IL-8 and serum amyloid A1 (SAA1), while it suppressed NF-κB activity, IκBα degradation and IκB kinase (IKK) activity. In conclusion, Zingiber officinale suppressed markers of hepatic inflammation in HFD-fed rats, as demonstrated by decreased hepatic cytokine gene expression and decreased NF-κB activation. The study demonstrates that the anti-inflammatory effect of Zingiber officinale occurs at least in part through the NF-κB signalling pathway.

Phase II study of the effects of ginger root extract on eicosanoids in colon mucosa in people at normal risk for colorectal cancer

Inhibitors of COX indicate that upregulation of inflammatory eicosanoids produced by COX, and in particular prostaglandin E(2) (PGE(2)), are early events in the development of colorectal cancer (CRC). Ginger has shown downregulation of COX in vitro and decreased incidence/multiplicity of adenomas in rats. This study was conducted to determine if 2.0 g/d of ginger could decrease the levels of PGE(2), 13-hydroxy-octadecadienoic acids, and 5-, 12-, and 15-hydroxyeicosatetraenoic acid (5-, 12-, and 15-HETE), in the colon mucosa of healthy volunteers. To investigate this aim, we randomized 30 subjects to 2.0 g/d ginger or placebo for 28 days. Flexible sigmoidoscopy at baseline and day 28 was used to obtain colon biopsies. A liquid chromatography mass spectrometry method was used to determine eicosanoid levels in the biopsies, and levels were expressed per protein or per free arachidonic acid. There were no significant differences in mean percent change between baseline and day 28 for any of the eicosanoids, when normalized to protein. There was a significant decrease in mean percent change in PGE(2) (P = 0.05) and 5-HETE (P = 0.04), and a trend toward significant decreases in 12-HETE (P = 0.09) and 15-HETE (P = 0.06) normalized to free arachidonic acid. There was no difference between the groups in terms of total adverse events P = 0.55). On the basis of these results, it seems that ginger has the potential to decrease eicosanoid levels, perhaps by inhibiting their synthesis from arachidonic acid. Ginger also seemed to be tolerable and safe. Further investigation in people at high risk for CRC seems warranted.

Ginger extract and polaprezinc exert gastroprotective actions by anti-oxidant and growth factor modulating effects in rats

BACKGROUND AND AIM

Contemporary medications used in the treatment of gastric ulcers involve the use of novel mucosal protective drugs. The present study aimed to investigate the gastroprotective effect of ginger extract and polaprezinc in a rat model of acetic acid-induced gastric ulcer.

METHODS

'Kissing' ulcers were induced in male Sprague-Dawley rats by using 60% acetic acid. Rhizoma Zingiber officinale (ginger) extract (1.5-5 g/kg) or polaprezinc (30 and 60 mg/kg) was orally given to the animals once daily for three consecutive days after ulcer induction. All animals were killed on day 5 by an overdose of ketamine.

RESULTS

Both ginger extract and polaprezinc significantly reduce the gastric ulcer area in a dose-dependent manner, with concomitant attenuation of the elevated activities of xanthine oxidase and myeloperoxidase, as well as malondialdehyde level in the ulcerated mucosa. Nevertheless, only polaprezinc could restore the mucosal glutathione level. Polaprezinc also causes the overexpression of basic fibroblast growth factor, vascular endothelial growth factor and ornithine decarboxylase, whereas ginger extract only increases the expression of the two growth factors in the gastric mucosa. Furthermore, polaprezinc could consistently downregulate the protein expression of tumor necrosis factor (TNF)-α, interleukin-1β, macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant-2α that have been activated in the ulcerated tissues, whereas ginger extract mainly inhibits the expression of the chemokines and to some extent TNF-α.

CONCLUSION

Ginger extract and polaprezinc both show anti-oxidation that consequently alleviates gastric mucosal damage and promotes ulcer healing, which together serve as effective mucosal protective agents.

Repeated oral administration of a squeezed ginger (Zingiber officinale) extract augmented the serum corticosterone level and had anti-inflammatory properties

We investigated the ability of a ginger extract to induce an immune response in RAW 264 cells and after a repeated oral administration to mice. The squeezed ginger extract augmented the production of tumor necrosis factor-α, interleukin-6, and monocyte chemotactic protein-1 when added to RAW 264 cells. This extract was collected as its ethanol-insoluble fraction. The oral administration of the squeezed ginger extract or its ethanol-insoluble fraction once or twice to mice also augmented the tumor necrosis factor-α production in peritoneal cells; however, its long-term administration had the opposite effect. The serum corticosterone level had increased after orally administering the squeezed ginger extract and was maintained during the administration period. Oral administration of the squeezed ginger extract also inhibited arachidonic acid-induced ear edema, but its repeated administration was needed to achieve an anti-inflammatory effect. These results suggest that the repeated administration of the aqueous constituents of ginger augmented the serum corticosterone level and that this may have gradually induced anti-inflammatory activity.

Acute effects of dietary ginger on muscle pain induced by eccentric exercise

Zingiber officinale, commonly known as ginger, has analgesic and antiinflammatory properties. The acute effects of ginger on muscle pain, inflammation and dysfunction induced by eccentric exercise were examined. Twenty-seven participants performed 24 eccentric actions of the non-dominant elbow flexors. In a double-blind, cross-over design, participants ingested a 2 g dose of ginger or placebo 24 h and 48 h after exercise. Pain intensity (0-100 mm), arm volume (water displacement), range-of-motion (goniometry) and metabolic rate were assessed before and 45 min after ingestion of ginger or placebo. Eccentric exercise induced moderate arm pain (39 ± 20 mm; mean ± SD) and dysfunction (14% decrease in ROM) and an increase in volume (1.8%). Overall, ginger consumption demonstrated no effect on muscle pain, dysfunction, or metabolic rate compared with placebo. In the sub-set of participants who consumed ginger 24 h after exercise, arm pain was reduced (13%, -5.9 ± 8.8 mm) the following day, 48 h after exercise. Participants who ingested placebo 24 h post-exercise exhibited no change in pain the following day (0.0 ± 14.7 mm). In conclusion, a single 2 g dose of ginger does not attenuate eccentric exercise-induced muscle pain, inflammation or dysfunction 45 min after ingestion. However, ginger may attenuate the day-to-day progression of muscle pain.

A 35-day gavage safety assessment of ginger in rats

Ginger (Zingiber officinale Roscoe, Zingiberacae) is one of the most commonly used spices around the world and a traditional medicinal plant that has been widely used in Chinese, Ayurvedic and Unani-Tibb medicines for several thousand years. However, there was still lack of systemic safety evaluation. We conducted a 35-day toxicity study on ginger in rats. Both male and female rats were daily treated with ginger powder at the dosages of 500, 1000 and 2000 mg/kg body weight by a gavage method for 35 days. The results demonstrated that this chronic administration of ginger was not associated with any mortalities and abnormalities in general conditions, behavior, growth, and food and water consumption. Except for dose-related decrease in serum lactate dehydrogenase activity in males, ginger treatment induced similar hematological and blood biochemical parameters to those of controlled animals. In general, ginger treatment caused no overt organ abnormality. Only at a very high dose (2000 mg/kg), ginger led to slightly reduced absolute and relative weights of testes (by 14.4% and 11.5%, respectively). This study provides a new understanding of the toxicological properties of ginger.

Antiallergic potential on RBL-2H3 cells of some phenolic constituents of Zingiber officinale (ginger)

In the present study on five pure phenolic compounds (1-5) isolated from the rhizomes of Zingiber officinale (ginger) and investigated for their antiallergic potency, rat basophilic leukemia (RBL-2H3) cells were incubated with these compounds and the release of beta-hexosaminidase was measured kinetically. The data obtained suggest that ginger rhizomes harbor potent compounds capable of inhibiting allergic reactions and may be useful for the treatment and prevention of allergic diseases.

Comparative effects of two gingerol-containing Zingiber officinale extracts on experimental rheumatoid arthritis

Ginger (Zingiber officinale) supplements are being promoted for arthritis treatment in western societies on the basis of ginger's traditional use as an anti-inflammatory in Chinese and Ayurvedic medicine. However, scientific evidence of ginger's antiarthritic effects is sparse, and its bioactive joint-protective components have not been identified. Therefore, the ability of a well-characterized crude ginger extract to inhibit joint swelling in an animal model of rheumatoid arthritis, streptococcal cell wall-induced arthritis, was compared to that of a fraction containing only gingerols and their derivatives. Both extracts were efficacious in preventing joint inflammation. However, the crude dichloromethane extract, which also contained essential oils and more polar compounds, was more efficacious (when normalized to gingerol content) in preventing both joint inflammation and destruction. In conclusion, these data document a very significant joint-protective effect of these ginger samples and suggest that nongingerol components are bioactive and can enhance the antiarthritic effects of the more widely studied gingerols.

Plasma pharmacokinetics and tissue distribution of [6]-gingerol in rats

[6]-Gingerol is one of the pungent components in ginger which has been found to possess various pharmacological effects. However, there is insufficient information on the properties of [6]-gingerol based on controlled pharmacokinetic studies. The aim of this study was to clarify distribution profiles of [6]-gingerol in blood and biological tissues of experimental rats. Rats were administered a 240 mg/kg dose of Gs (a ginger extract, containing 53% [6]-gingerol) by oral ingestion. Plasma samples were collected at 2.5, 5, 7.5, 10, 15, 20, 30, 45 min, and 1, 1.5, 2, 3, 4 h after dosing (eight samples per time point), and brain, heart, lung, spleen, liver, kidney, stomach and small intestine tissues were collected at 5, 15, 30 min and 1, 2, 4 h after dosing (five animals per time point). Samples were prepared by a liquid-liquid extraction procedure and the extracts were assayed by HPLC-UV. After per oral application, [6]-gingerol was absorbed rapidly into the plasma, and the maximal concentration (4.23 microg/ml) was reached after 10 min post dosing. [6]-Gingerol plasma concentrations declined with time in a biexponential pattern. The elimination half-time at the terminal phase was 1.77 h and the apparent total body clearance was 40.8 l/h. When administered orally, [6]-gingerol was well distributed to the tissues examined, with the highest concentrations found in the gastrointestinal tract. Maximal concentrations of [6]-gingerol were reached in most tissues at 0.5 h post-dosing. The concentrations of [6]-gingerol in tissues all were higher than in plasma with corresponding tissue to plasma ratios greater than 1 after 0.25 h post-dose, showing high tissue partitioning and extensive distribution.