Immune system effects of echinacea, ginseng, and astragalus: a review

In vitro and in vivo immunomodulating and immunorestorative effects of Astragalus membranaceus

Astragalus membranaceus is a common traditional Chinese medicinal plant widely used as a tonic to enhance the body's natural defense mechanisms. In this study, bioactive fractions were isolated from the roots of Astragalus membranaceus. One of these fractions, designated as AI, was found to be the most potent with respect to its mitogenicity on murine splenocytes. Effects of AI on both specific and nonspecific immunity in mouse models were examined. Results showed that AI could exhibit mitogenic and co-mitogenic activities on mouse splenocytes, both in vitro and in vivo. Experiments in human cell culture demonstrated that AI was also active on human lymphocytes. It was found that AI was mitogenic to T cell depleted population but virtually inactive on B cell depleted population. Intraperitoneal injection of AI into mice markedly augmented the antibody response to sheep red blood cells. Besides, both the influx of macrophages into the peritoneal cavity and the phagocytic activity of macrophages were found to be enhanced by AI in vivo. On the other hand, AI could significantly increase the interleukin-2 receptor expression on mouse splenocytes in vitro. In terms of immunorestorative activity, it was found that AI could restore the lymphocyte blastogenic response of the older mice to values that are normally found in the younger mice. Moreover, administration of AI in vivo could partially restore the depressed immune functions in tumour-bearing mice and cyclophosphamide-treated mice. Collectively, the results clearly showed that AI could exhibit immunomodulating and immunorestorative effects, both in vitro and in vivo.

Pesticide multiresidue analysis in Panax ginseng (C. A. Meyer) by solid-phase extraction and gas chromatography with electron capture and nitrogen-phosphorus detection

An analytical multi-residue method using gas chromatography coupled with electron capture and a nitrogen-phosphorus detector was investigated for the simultaneous determination of 18 commonly used insecticides and fungicides in Korean ginseng (Panax ginseng C. A. Meyer). Samples were previously extracted with an acetonitrile and cleaned up by solid-phase extraction (SPE). The calibration curves were linear, with determination coefficients higher than 0.989. Recoveries at concentrations between 0.01 and 14.9 ppm ranged from 72.3 to 117.2%, with precision, which was expressed as relative standard deviation (RSD), at values lower than 5%. The proposed method was applied to the determination of pesticide levels from 12 ginseng samples, taken from four different agricultural areas of Jeonnam province, where several insecticides and fungicides were applied. Except in one sample, tolclofos-m was the only pesticide contained at a level lower than the maximum residue limits (MRL) authorized by the Korea Food and Drug Administration (KFDA) in real ginseng samples grown for 4, 5 and 6 years.

Warned, but not well armed: preventing viral upper respiratory infections in households

ABSTRACT The purpose of this state‐of‐the‐science review was to identify strategies and household‐level interventions for public health nurses to help prevent the acquisition and spread of viral upper respiratory infections (URI) in the community. Even though viral URI are a major global economic and social problem, surprisingly little research has been conducted to attempt to prevent them or reduce their transmission, probably because URI (with the exception of epidemic influenza) are generally considered to be mild and self‐limited. Based on the research to date, public health nurses can use several promising strategies for prevention: (a) provide more tailored educational messages regarding preventive strategies such as vaccination, hand hygiene, spatial separation of infected household members, avoidance of antibiotics to treat viral URI, and environmental cleaning (e.g., for toys or other shared items), which are delivered personally rather than passively (e.g., pamphlets placed in a waiting room); (b) use each patient encounter in any setting to encourage influenza vaccination for relevant risk groups; (c) encourage use of alcohol hand sanitizers by household members during the cold and flu season; and (d) provide opportunities for skill development for adult and child household members (e.g., cover your cough, when to seek care or an antibiotic).

Effects of the Chinese herbal medicines Bupleuri radix, Ginseng radix, and Zingiberis rhizoma on lymphatic vessel activity in rats

The aim of the present study was to determine the effects of the Chinese herbal medicines Bupleuri radix, Ginseng radix and Zingiberis rhizoma on spontaneous lymphatic vessel activity. The effect of each herbal medicine on in vivo lymphatic flow was examined by injection of dye into the femoral regions of rats after feeding with the herbal medicines. In an in vitro study, spontaneous changes in diameter of the rat thoracic duct were monitored, and each segment was exposed to each herbal medicine. In the in vivo study, 100% of the right iliac lymphatic node were positively stained in the herbal medicine group, whereas only 40% of the node were positively stained in the control group. In the in vitro study, Bupleuri radix and Ginseng radix increased the amplitude of spontaneous activity of lymphatic vessels in a concentration-dependent manner with or without L-NAME, an NO synthase inhibitor. The results indicated that the herbal medicines Bupleuri radix and Ginseng radix activated spontaneous lymphatic vasomotion and lymph flow, and the mechanisms of this effect seem to be independent of endothelial cells.

Methodological Issues in the Investigation of Ginseng as an Intervention for Fatigue

BACKGROUND

Although literature suggests that fatigue is commonly reported by women during and after breast cancer treatment, treatment options are limited. Although ginseng is widely used in Asian countries as a tonic to increase energy, its efficacy for treating cancer-related fatigue has not been carefully studied. We conducted a pilot study to evaluate the feasibility of a larger clinical trial to investigate the efficacy of ginseng for treating breast cancer-related fatigue.

PARTICIPANTS/METHODS

Breast cancer survivors seeking treatment for fatigue were recruited to participate in an 8-week randomized, double-blind, placebo-controlled trial.

RESULTS

A variety of practical problems were encountered in the study, including large numbers of survivors with conditions that were possible contraindications to ginseng use, inability to achieve blinding for the intervention because of strong odor from the ginseng, and measurement device failure.

DISCUSSION

Evaluating ginseng for breast cancer treatment-related fatigue is a great challenge, particularly if a blinded randomized design is desired. This article provides insight into issues related to investigating complementary therapies and the importance of pilot studies for identifying methodological problems.

Increase of insulin secretion by ginsenoside Rh2 to lower plasma glucose in Wistar rats

1. The aim of the present study was to clarify the role of ginsenoside Rh2 as the active compound in Panax ginseng root for lowering plasma glucose in animals. 2. Plasma glucose was assessed using the glucose oxidase method. Changes in the levels of insulin and C-peptide in plasma were measured by ELISA using commercially available kits. 3. After intravenous injection into fasting Wistar rats for 60 min, ginsenoside Rh2 (0.1-1.0 mg/kg) decreased plasma glucose in a dose-dependent manner. In parallel with the decrease in plasma glucose, increases in plasma insulin levels, as well as plasma C-peptide, were observed in rats receiving the same treatment. These effects of Rh2 were reversed by atropine (0.1-1.0 mg/kg), but not affected by the ganglionic nicotinic antagonists pentolinium or hexamethonium (both at 7.5 mg/kg). 4. Disruption of synaptically available acetylcholine (ACh) using an inhibitor of choline uptake (hemicholinium-3; 1-10 microg/kg) or an inhibitor of vesicular ACh transport (vesamicol; 1.5-3.5 mg/kg) abolished the actions of Rh2. In addition, physostigmine (0.1-0.5 mg/kg), at a concentration sufficient to inhibit acetylcholinesterase, enhanced the actions of the ginsenoside Rh2. Thus, mediation of the effects of Rh2 to enhance insulin secretion by ACh released from nerve terminals can be considered. 5. Blockade of the increase in plasma insulin and the plasma glucose-lowering action of Rh2 by 4-diphenylacetoxy-N-methylpiperdine methiodide (4-DAMP; 5-10 microg/kg) indicates the participation of muscarinic M(3) receptors. Increases in plasma C-peptide level induced by Rh2 were also sensitive to 4-DAMP. 6. The results of the present study suggest that ginsenoside Rh2 has the ability to increase insulin secretion as a result of the release of ACh from nerve terminals that then stimulates muscarinic M(3) receptors in pancreatic cells. This finding shows the mechanism for the plasma glucose-lowering action of ginsenoside Rh2, that is one of the major principles contained in P. ginseng root. Thus, ginsenoside Rh2 may be applied as an adjuvant for the management of diabetes.

Macrophage immunomodulatory activity of polysaccharides isolated from Juniperus scopolorum

Extracts of cones and leaves of different species of the genus Juniperus have been used for centuries to treat a variety of medical problems; however, little is known about the active components conferring therapeutic properties to these extracts. To address this issue, we extracted water-soluble polysaccharides from Juniperus scopolorum cones and used ion exchange and size exclusion chromatography to separate them into five fractions, with estimated Mr of 30, 60, 100, 200, and 680 kDa, respectively. All fractions contained type II arabinogalactan in their structure, as determined by reaction with Yariv reagent and structural analysis by proton nuclear magnetic resonance spectroscopy, but lacked complement fixing activity. Analysis of the effects of Juniper polysaccharides on murine peritoneal macrophages, cultured J774.A1 macrophages, and human mononuclear phagocytes demonstrated that the high molecular weight polysaccharide fractions (200 and 680 kDa) had potent immunomodulatory activity. These polysaccharide fractions primed macrophages for an enhanced respiratory burst, directly stimulated NO production via induction of nitric oxide synthase, and induced macrophages to secrete both inflammatory (IL-1, IL-6, TNF-alpha, and IL-12) and anti-inflammatory (IL-10) cytokines. These data suggest that at least part of the beneficial therapeutic effects reported for extracts of juniper cones are due to modulation of monocyte/macrophage immune functions.

Natural health products, modulation of immune function and prevention of chronic diseases

The immune system is increasingly found to be involved in the development of several chronic illnesses, for which allopathic medicine has provided limited tools for treatment and especially prevention. In that context, it appears worthwhile to target the immune system in order to modulate the risk of certain chronic illnesses. Meanwhile, natural health products (NHPs) are generating renewed interest, particularly in the prevention and treatment of several chronic diseases. Over 20 scientists from fields related to immune function and NHPs were thus convened to establish the state of knowledge on these subjects and to explore future research directions. This review summarizes the result of discussions held during the symposium. It thus seeks to be thought provoking rather than to comprehensively cover such broad areas of research. Notably, a brief overview of the immune system is presented, including potentially useful targets and strategies to keep it in an equilibrated state, in order to prevent certain disorders. The pertinence and limitations of targeting the immune system to prevent chronic diseases is also discussed. The paper then discusses the usefulness and limitations of current experimental tools available to study the immune modulating effects of NHPs. Finally, a concise review of some of the most studied NHPs showing promising immunomodulatory activity is given, and avenues for future research are described.

Effects produced by Royal Jelly on haematopoiesis: relation with host resistance against Ehrlich ascites tumour challenge

Royal jelly (RJ) was shown to exhibit immunomodulatory properties, although its biological activity is still unclear. In order to elucidate the mechanism whereby RJ activates the immunological system, we examined the role of this substance on the haematopoietic response of Ehrlich ascites tumour (EAT)-bearing mice. Our results demonstrated that RJ prevented the myelosupression induced by the temporal evolution of the tumour and abrogated the splenic haematopoiesis observed in EAT-bearing mice. The stimulating effect of RJ was also observed in vitro on the multipotent bone marrow stem cells, evaluated by the long-term bone marrow cultures (LTBMCs). The study of survival clearly showed the antitumour activity of RJ. Treatment was given prophylactically for 20 days and therapeutically for 3, 8 and 13 days. Except for the treatment with the lower dose of 500 mg/kg, given for 23 days, all the other dose schedules were able to prolong survival. A more effective antitumoural response was observed with the more prolonged treatment regimen. In this regard, the administration of RJ for 33 days produced the highest protection reaching an extension of survival at about 38%, 71% and 85% for the doses of 500, 1000 and 1500 mg/kg, respectively, whereas with the 23 and 28 days treatment schedules, survival increased at a rate of 19% and 23%, respectively, and comparable results were found among the effective doses of RJ. Increased survival rate might be related to the decreased Prostaglandin E2 (PGE2) levels observed in EAT-bearing mice after RJ treatment. These results point to RJ as a promising modifier of biological response leading to myeloprotection and antitumour activity.

Effects of fish-derived lipoprotein extracts on activation markers, Fas expression and apoptosis in peripheral blood lymphocytes

Several factors may influence numbers and function of peripheral blood lymphocytes (PBLs) by different processes. We conducted this study to evaluate the effect of E-CAB-94011 and E-JUR-94013, two marine fish extracts from S. scombrus and T. trachurus, respectively, on in vitro PBLs activation and on the expression and functionality of Fas, a cell surface molecule that plays a central role in immune homeostasis and cytotoxic activity. PBLs from 24 healthy volunteers were isolated and flow cytometry was performed to measure the state of activation, Fas expression and apoptosis of PBLs. Functionality of Fas was tested by assessing apoptosis after incubation of isolated lymphocytes with agonistic anti-Fas antibodies in blood samples treated with both E-CAB-94011 and E-JUR-94013. Studies on the lymphocyte cell marker suggest a clear immune activation as measured by the increased levels of CD25, CD8, CD38, CD19 and HLA-DR in vitro expression on lymphocytes treated with both extracts. In addition, a significant reduction in the percentages of apoptotic CD19(+)CD38(+) double positive lymphocytes could be demonstrated in the treated samples with respect to controls (p<0.05). Therefore the present results indicate that both E-CAB-94011 and E-JUR-94013 in vitro are powerful immunoregulatory, increasing immune surveillance.

Radioprotective potential of ginseng

A majority of potential radioprotective synthetic compounds have demonstrated limited clinical application owing to their inherent toxicity, and thus, the seeking of naturally occurring herbal products, such as ginseng, for their radioprotective capability has become an attractive alternative. In general, ginseng refers to the roots of the species of the genus Panax. As a medicinal herb, ginseng has been widely used in traditional Chinese medicine for its wide spectrum of medicinal effects, such as tonic, immunomodulatory, antimutagenic, adaptogenic and antiaging activities. Many of its medicinal effects are attributed to the triterpene glycosides known as ginsenosides (saponins). This review addresses the issue of the radioprotective effects of ginseng on mammalian cells both in vitro and in vivo. Results indicate that the water-soluble extract of whole ginseng appears to give a better protection against radiation-induced DNA damage than does the isolated ginsenoside fractions. Since free radicals play an important role in radiation-induced damage, the underlying radioprotective mechanism of ginseng could be linked, either directly or indirectly, to its antioxidative capability by the scavenging free radicals responsible for DNA damage. In addition, ginseng's radioprotective potential may also be related to its immunomodulating capabilities. Ginseng is a natural product with worldwide distribution, and in addition to its antitumor properties, ginseng appears to be a promising radioprotector for therapeutic or preventive protocols capable of attenuating the deleterious effects of radiation on human normal tissue, especially for cancer patients undergoing radiotherapy.

Panax ginseng reduces adriamycin-induced heart failure in rats

The purpose of this study was to investigate the protective effects of Panax ginseng on adriamycin-induced heart failure. Wistar rats were divided into four groups: control, adriamycin, ginseng and adriamycin with ginseng. Adriamycin (cumulative dose, 15 mg/kg) was administered to rats in six equal intraperitoneal injections over a period of 2 weeks. Ginseng was administered via an oral feeding tube once a day for 30 days (cumulative dose, 150 g/kg). At the end of the 5 week post-treatment period, the hearts of the rats were used to study the synthesis rates of DNA, RNA and protein, myocardial antioxidants and lipid peroxidation. At the end of 3 weeks treatment, heart failure was characterized by ascites, congested liver and depressed cardiac function. Nucleic acid as well as protein synthesis was inhibited, lipid peroxidation was increased and myocardial glutathione peroxidase activity was decreased indicating adriamycin-induced heart failure. In contrast, the administration of ginseng, before and concurrent with adriamycin, significantly attenuated the myocardial effects, lowered the mortality as well as the amount of ascites, increased in myocardial glutathione peroxidase, macromolecular biosynthesis and superoxide dismutase activities, with a concomitant decrease in lipid peroxidation. These findings indicated that ginseng may be partially protective against adriamycin-induced heart failure.