With an increasing number of cancer patients seeking an improved quality of life, complementary and alternative therapies are becoming more common ways to achieve such improvements. The potential risks of concurrent administration are serious and must be addressed. However, comprehensive evidence for the risks and benefits of combining anticancer drugs with traditional herbs is rare. Pharmacokinetic investigations are an efficient way to understand the influence of concomitant remedies. Therefore, this study aimed to collect the results of pharmacokinetic studies relating to the concurrent use of cancer chemotherapy and complementary and alternative therapies. According to the National Health Insurance (NHI) database in Taiwan and several publications, the three most commonly prescribed formulations for cancer patients are Xiang-Sha-Liu-Jun-Zi-Tang, Jia-Wei-Xiao-Yao-San and Bu-Zhong-Yi-Qi-Tang. The three most commonly prescribed single herbs for cancer patients are Hedyotis diffusa, Scutellaria barbata, and Astragalus membranaceus. Few studies have discussed herb-drug interactions involving these herbs from a pharmacokinetics perspective. Here, we reviewed Jia-Wei-Xiao-Yao-San, Long-Dan-Xie-Gan-Tang, Curcuma longa and milk thistle to provide information based on pharmacokinetic evidence for healthcare professionals to use in educating patients about the risks of the concomitant use of various remedies.

Acute myeloid leukemia (AML) is the most deadly subtype of leukemia, and many patients with this disease seek other complementary therapies, one of which is Chinese medicine. We set out to provide reliable data regarding the benefit of Chinese herbal medicine (CHM) for AML patients, using mortality as the main outcome measure. We also characterized the herbal prescriptions of patients.

Using the Taiwanese National Health Insurance Research Database, we performed a nationwide population-based cohort study among AML patients from 1997 to 2010. The Cox regression model was used to adjust for comorbidities and other variables, and the hazard ratios (HRs) of CHM users and non-CHM users were compared.

After 1:1 matching, 498 patients were included into the study. The HR of the CHM group was 0.41 (95% CI = 0.26-0.65; P = .0001) compared with the non-CHM group. This decrease in HR was also shown to be dose dependent ( P < .001). The 3 single-herbs most commonly prescribed were Salvia miltiorrhiza (Dan Shen), Astragalus membranaceus (Huang Qi), and Spatholobus suberectus (Ji Xue Teng). The 3 mutli-herb products most commonly prescribed were Jia Wei Xiao Yao San, Gui Pi Tang, and Qi Ju Di Huang Wan.

Prospective controlled clinical data is still needed, however, this study provides real-world data regarding the benefit AML patients may have from CHM. This study suggests that all AML patients, regardless of age or other prognostic factors, may achieve longer survival times when receiving CHM in addition to standard therapy.

Worldwide, cervical cancer (CC) is the third most common malignancy in women, and it remains a leading cause of cancer-related death of women. Genomic studies indicate that phosphoinositide 3-kinase (PI3K)/AKT signaling is one of the most frequently deregulated pathways in several human cancers, including CC. This signaling pathway has an important role in cancer cell proliferation, survival, motility, and metabolism, and therefore could be an attractive therapeutic target. In a previous study, we used a sensitive and high-speed homogeneous assay for the detection of kinase activity and for screening of PI3K/AKT signaling inhibitors in a high-throughput screening (HTS) format and then obtain formononetin, as an O-methylated isoflavone existed in a number of plants and herbs like Astragalus membranaceus. We showed that formononetin inhibited the phosphorylation of AKT and induced the apoptosis of CC cell line HeLa in a dose-dependent manner. Furthermore, formononetin suppressed xenograft tumor growth in nude mice. Our results indicated that formononetin may be used as an anti-cancer drug for cervical cancer in the future.

We previously reported that Astragalus polysaccharide (APS) extracted from Chinese medicine Astragalus membranaceus (Fisch.) Bge, attenuates hypertrophy of neonatal rat ventricular myocytes (NRVMs) induced by isoproterenol (Iso). The present study was designed to investigate the effects and the possible mechanism of APS on Iso-induced hypertrophy in rats and NRVMs with focus on tumor necrosis factor α (TNF-α)/peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) signaling mediated energy biosynthesis. 36-Week old rats were randomly divided into 3 groups: (1) Control, rats received vehicle; (2) Iso, rats received isoproterenol injections; (3) Iso+APS, rats received isoproterenol injections and APS. NRVMs were divided into similar groups as rats. The results showed that combination of APS with Iso significantly attenuated the pathological changes, reduced the ratios of heart weight/body weight (HW/BW) and left ventricular weight/BW (LVW/BW), improved the cardiac hemodynamics, down-regulated mRNA and protein expression of atrial natriuretic peptide (ANP), increased the ratios of ATP/ADP and ATP/AMP, and decreased the content of free fatty acid (FFA) in heart tissue of rats compared with Iso alone. In addition, pretreatment with APS significantly decreased the surface area and protein content, down-regulated mRNA and protein expression of ANP, increased the ratios of ATP/ADP and ATP/AMP, and decreased the content of FFA in NRVMs compared with Iso alone. Furthermore, APS increased the protein expressions of ATP5D, the σ subunit of ATP synthase, PGC-1α and pyruvate dehydrogenase kinase 4 (PDK4) in tissue and NRVMs respectively and inhibited the production of TNF-α in serum and culture medium compared with Iso alone. The results suggested that APS attenuates Iso-induced cardiac hypertrophy through regulating TNF-α/PGC-1α signaling mediated energy biosynthesis.

Cycloastragenol (CAG) is a triterpenoid saponin compound and a hydrolysis product of the main active ingredient in Astragalus membranaceus (Fisch.) Bunge. An increasing body of evidence has indicated that CAG has a wide spectrum of pharmacological functions, which are attracting attention in the research community. The aim of the present review paper was to review and elucidate the advanced study of CAG. The focus was on advanced studies of CAG in English and Chinese databases; the literature was collected and reviewed to summarize the latest efficacy, pharmacokinetics and adverse reactions of CAG. Extensive pharmacological effects have been attributed to CAG, including telomerase activation, telomere elongation, anti-inflammatory and anti-oxidative properties; CAG has also been reported to improve lipid metabolism. Clinical research has demonstrated that CAG activates telomerase in humans and ameliorates various biomarkers. CAG is absorbed through the intestinal epithelium via passive diffusion and undergoes first-pass hepatic metabolism. Within a certain dose range, oral CAG is relatively safe; however, underlying mechanisms associated with CAG are not clear, and thus, we should be aware of potential adverse reactions associated with CAG. According to existing studies and clinical trials, CAG is safe and has broad application prospects. However, further studies are required to fully understand its efficacy and potential adverse reactions, and to ensure the proper use of CAG is applied to treat diseases clinically.

Astragalus membranaceus, also known as huang qi, a traditional Chinese medicine, is often used in formulas for deficiency of vital energy characterized by limb weakness, pale face, and dizziness. Previous studies have shown that Astragalus membranaceus could attenuate intestinal ischemia-reperfusion injury induced by hemorrhagic shock in rats; however, the underlying mechanism still remains unclear. Using a hemorrhagic shock rat model to examine the effect of Astragalus membranaceus on intestinal mucosa injury induced by ischemia-reperfusion, we found that treatment (20 g crude drugs/kg, i.v.) produced antioxidative effects in the intestinal mucosa of rats after ischemia-reperfusion (p < 0.05). We also found that Astragalus membranaceus could partly attenuate intestinal mucosa ischemia-reperfusion injury (chiu's score, apoptosis index p < 0.05). These results suggest that Astragalus membranaceus reduces intestinal mucosa injury induced by ischemia-reperfusion in rats, at least in part, through its anti-oxidative effects.

Huangqi (Astragalus membranaceus), a traditional Chinese medicine, has been used to ameliorate side effects of cancer chemotherapy in China. However, little is known about its molecular mechanisms. Here we show that induction of K562 or HEL cells with 1.5 mg/ml of Huangqi (Hex) (Components extracted from Huangqi) for 3-5 d results in the expression of beta-globin gene in both cell lines and leads to terminal differentiation. Moreover, the apoptosis in HEL cells can be induced by increasing concentration of Huangqi (Hex) to 4.5 mg/ml for 3-5 d. Upregulation of Apaf-1, caspase-3 and acetylcholinesterase (AChE) in HEL cells may play a crucial role in the process of apoptosis. The prospect of inducing expression of adult (beta) globin gene and apoptosis selectively in cancer cells is obviously attractive from a therapeutic point of view.

A structurally identified new compound named malonylastragaloside I was isolated and obtained from Radix Astragali. This novel compound was found to be unstable especially under high temperature and pH value. Using sonication extraction, addition of formic acid, and an efficient medium pressure ODS C(18) column chromatography method, a high yield of 40 mg of this compound was obtained from 150 g of powdered crude herbal medicine. Malonylastragaloside I was structurally characterized by NMR and ESI quadrupole TOF MS. With the strategy of target precursor ions scan, a total of 22 astragalosides including 8 astragaloside malonates were screened and characterized from the methanolic extract of Radix Astragali by HPLC-Q-TOF/MS. The eight astragaloside malonates were found in both Astragalus membranaceus var. mongholicus and A. membranaceus. The results provided a real profile of various triterpene saponins in Radix Astragali. It is a first report regarding isolation and characterization of astragaloside malonates in Astragalus species.

The traditional Asian medicinal herb, roots of Astragalus (A.) membranaceus (Leguminosae), is used for many purposes, some of which are purported to stimulate the release of growth hormone in vivo. Extracts of A. membranaceus were tested to determine whether they stimulate the release of growth hormone in rat pituitary cell culture. A. membranaceus was extracted sequentially with 80% ethanol (fraction A), n-hexane (fraction B); the test compound from the herbal extraction was isolated using silica gel column chromatography and was identified with spectral data. Test compound was also extracted by traditional boiling water methods. Induction of growth hormone in pituitary cell culture was conducted with isolated compounds and extracted fractions of A. Radix (dried roots of A. membranaceus). The fraction A was not active in the rat pituitary cell culture, but the fraction B derived from the ethanol fraction stimulated the release of growth hormone in culture. Six compounds from fraction B (1-6) were isolated and identified previously. The compounds 1,2-benzendicarboxylic acid diisononylester (1), beta-sitosterol (2), and 3-O-beta-D-galactopyranosyl-beta-sitosterol (5) did not induce growth hormone release in the culture. Formononetin (3), 9Z,12Z-octadecadienoic acid (4), stigmast-4-en-6beta-ol-3-one (6) and 98-E, a mixture of 1'-9,12-octadecadienoic acid (Z,Z)-2',3'-dihydroxy-propylester (7) and 1'-hexadecanoic acid-2',3'-dihydroxy-propylester (8) stimulated the release of growth hormone in the rat pituitary cell culture significantly compared to the control. In conclusions, four compounds isolated from extracts of A. Radix induced growth hormone release in the rat pituitary cell culture. The 98-E isolate was the most active inducer of growth hormone release.

In our previous study, a novel cold-water-soluble polysaccharide (APS4) was isolated from Astragalus membranaceus. This study aimed to evaluate the proliferation inhibition and apoptosis-induced effects of APS4 on human gastric carcinoma MGC-803 cells and to investigate its potential molecular mechanism. It was found that APS4 could significantly suppress the proliferation of MGC-803 cells in a concentration- and time-dependent manner. Morphologic observations and Annexin V-FITC/PI staining showed that APS4-treated MGC-803 cells exhibited typical morphological characteristics of apoptosis. Cell cycle detection revealed that APS4 could arrest MGC-803 cells in S phase of the cell cycle. Additionally, APS4 treatment could induce the mitochondria-dependent apoptosis, which was closely related to the accumulation of intracellular ROS, the collapse of mitochondrial membrane potential, the increase of the pro-apoptotic/anti-apoptotic (Bax/Bcl-2) ratios, the release of cytochrome c, further activating the expression of caspase-9/-3 and the cleavage of poly-ADP-ribose polymerase (PARP) in MGC-803 cells. Taken together, our results suggested that APS4 had observable apoptosis-induced effects on MGC-803 cells via arresting the cell cycle in S phase and inducing the intrinsic mitochondrial apoptosis pathway.

Eight phenolic compounds were isolated using bio-guided isolation and purified from the roots of Astragalus taipaishanensis Y. C. Ho et S. B. Ho (A. taipaishanensis) for the first time. Their structures were elucidated by ESI-MS, HR-ESI-MS, 1D-NMR and 2D-NMR as 7,2'-dihydroxy-3',4'-dimethoxy isoflavan (1), formononetin (2), isoliquiritigenin (3), quercetin (4), kaempferol (5), ononin (6), p-hydroxybenzoic acid (7) and vanillic acid (8). Six flavonoids (compounds 1-6) exhibited stronger antioxidant activities (determined by DPPH, ABTS, FRAP and lipid peroxidation inhibition assays) than those of BHA and TBHQ and also demonstrated noticeable protective effects (particularly quercetin and kaempferol) on Escherichia coli under oxidative stress. Additionally, the chemical constituents compared with those of Astragalus membranaceus and the structure-activity relationship of the isolated compounds were both analyzed. The results clearly demonstrated that A. taipaishanensis has the potential to be selected as an alternative medicinal and food plant that can be utilized in health food products, functional tea and pharmaceutical products.

OBJECTIVE

To examine the effects of traditional Chinese medicine (TCM) on alcohol-induced fatty liver in rats. TCM consists of Astragalus membranaceus, Morus alba, Crataegus pinnatifida, Alisma orientale, Salvia miltiorrhiza, and Pueraria lobata.

METHODS

The rats were separated randomly into five groups. One (the CD group) was fed a control diet for 10 wk, another (the ED group) fed an ethanol-containing isocaloric liquid diet for 10 wk, and the last three (the TCM group) were fed an ethanol-containing isocaloric liquid diet for 10 wk and dosed orally with TCM (222 mg/kg.d, TCM222; 667 mg/kg.d, TCM667; and 2 000 mg/kg.d, TCM2000, respectively) weekly during the last 4 wk.

RESULTS

ED group developed fatty liver according to lipid profile and liver histological findings. Compared with the control group, liver/body weight, serum triglyceride (TG) and total cholesterol (TC), liver TG and TC, serum alanine aminotransferase (ALT) and aspartic aminotran-sferase (AST) significantly increased in the ED group. Whereas, in the rats administered with TCM, liver/body weight, serum TG and TC, liver TG and TC, serum ALT and AST were significantly decreased, and the degree of hepatic lipid droplets was markedly improved compared with those in the ED group.

CONCLUSIONS

TCM treatment causes significant reduction in alcohol-induced lipid hepatic accumulation, reversing fatty liver and liver damage, and can be used as a remedy for alcoholic fatty liver.

OBJECTIVE

To establish the mechanism responsible for the stimulation of glucose uptake by Astragalus polysaccharide (APS), extracted from Astragalus membranaceus Bunge, in L6 myotubes in vitro.

METHODS

APS-stimulated glucose uptake in L6 myotubes was measured using the 2-deoxy-[(3)H]-D-glucose method. The adenine nucleotide contents in the cells were measured by HPLC. The phosphorylation of AMP-activated protein kinase (AMPK) and Akt substrate of 160 kDa (AS160) was examined using Western blot analysis. The cells transfected with 4P mutant AS160 (AS160-4P) were constructed using gene transfer approach.

RESULTS

Treatment of L6 myotubes with APS (100-1600 μg/mL) significantly increased glucose uptake in time- and concentration-dependent manners. The maximal glucose uptake was reached in the cells treated with APS (400 μg/mL) for 36 h. The APS-stimulated glucose uptake was significantly attenuated by pretreatment with Compound C, a selective AMPK inhibitor or in the cells overexpressing AS160-4P. Treatment of L6 myotubes with APS strongly promoted the activation of AMPK. We further demonstrated that either Ca(2+)/calmodulin-dependent protein kinase kinase β (CaMKKβ) or liver kinase B1 (LKB1) mediated APS-induced activation of AMPK in L6 myotubes, and the increased cellular AMP: ATP ratio was also involved. Treatment of L6 myotubes with APS robustly enhanced the phosphorylation of AS160, which was significantly attenuated by pretreatment with Compound C.

CONCLUSIONS

Our results demonstrate that APS stimulates glucose uptake in L6 myotubes through the AMP-AMPK-AS160 pathway, which may contribute to its hypoglycemic effect.

Renal fibrosis, a progressive process characterized by the accumulation of extracellular matrix (ECM) leading to organ dysfunction, is a characteristic of chronic kidney diseases. Among fibrogenic factors known to regulate the renal fibrotic process, transforming growth factor-β (TGF-β) plays a central role. In the present study, we examined the effect of Astragaloside IV (AS-IV), a component of the traditional Chinese medicinal plant Astragalus membranaceus, on the processes associated with renal fibrosis in cultured mouse renal fibroblasts treated with TGF-β1. RT-PCR, western blotting, immunofluorescence staining and collagen assays showed that AS-IV suppressed TGF-β1 induced fibroblast proliferation, transdifferentiation, and ECM production in a dose-dependent manner. Examination of the underlying mechanisms showed that the effect of AS-IV on the inhibition of fibroblast differentiation and ECM formation were mediated by its modulation of the activity of the MAPK and NF-κB signaling pathways. Taken together, our results indicate that AS-IV alleviates renal interstitial fibrosis via a mechanism involving the MAPK and NF-κB signaling pathways and demonstrate the therapeutic potential of AS-IV for the treatment of chronic kidney diseases.

The decoction of a combination of two Chinese herbs, Astragali Radix (the roots of Astragalus membranaceus var. mongholicus) and Angelicae Sinensis Radix (the roots of Angelica sinensis), here named as A&A, has been demonstrated to have renoprotective effects in several animal models and may be considered as a complementary therapeutic medicine for chronic kidney disease. In this study, genomic approaches were employed to identify expression signatures in the obstructed kidney, which may be linked to the molecular actions associated with anti-fibrotic effects of A&A. Ninety-six male Wistar rats were divided randomly into sham, SAA (sham + A&A), UUO (unilateral ureteral obstruction), and UAA (UUO + A&A) groups. The rats in the SAA and UAA groups were administered A&A (14 g/kg) by oral gavage once daily; the ones in the sham and UUO groups were given equal volumes of water. Eight rats from each group were sacrificed at days 3, 7, and 10 after the operation, respectively. Changes in gene expression in the kidneys were determined using Affymetrix RAE-230A GeneChips. The differential expression of known genes between UAA and UUO was confirmed by RT-PCR. The results revealed that 40, 65, and 104 genes were upregulated and 30, 36, and 40 genes downregulated in UUO compared with the sham group at days 3, 7, and 10, respectively. Compared to the UUO group, eight genes were upregulated and two genes were downregulated at day 3 in the UAA group, and two genes were upregulated at day 10. These genes included transient receptor protein 3 (TRP3), bone marrow stromal cell antigen 1 (BST-1), peroxisomal biogenesis factor 6 (PEX6), xanthine dehydrogenase (XDH), cytochrome P450 subfamily I member A1 (CYP1A1), serine/cysteine proteinase inhibitor clade E member1 (PAI-1), fibroblast growth factor 23 (FGF23), and five ESTs. Among these genes, differential expression of PAI-1, FGF23, and CYP1A1 were further confirmed by RT-PCR. These data provide the evidence that the anti-fibrotic effects of A&A are mediated through multiple pathways in obstructive nephropathy, and novel mechanisms may be involved in the increasing degeneration of ECM, decreasing ROS reaction, and regulation of the calcium-phosphate metabolism.

The article aims to review various Traditional Chinese Medicines (TCMs) with both osteogenic and angiogenic effects, alone and in combination, and to consider whether these TCMs promote osteogenesis via angiogenesis and vascular endothelial growth factor (VEGF). Each of the TCMs involving in osteogenesis was searched through PubMed and CBMdisc using its Latin name and English name, and keywords such as 'osteogenesis', 'bone', 'osteoblast', 'angiogenesis', 'VEGF' were used. A total of 241 articles were screened from PubMed and CBMdisc. The articles were only chosen if they discussed the relationship of the TCMs with bone formation and/or angiogenesis. Twenty-seven articles were chosen, of which 16 were in English and 11 were in Chinese with English abstract. As a result, the TCMs (Danshen or Salvia miltiorrhiza Bunge, Danggui or Angelica sinensis, Astragalus membranaceus Bunge or Huangqi, and Ge Gan or Puerarin radix) that have a relationship with both osteogenesis and angiogenesis were screened out. It is found that the aforementioned TCMs enhance angiogenesis and osteogenesis. They show a positive effect on bone formation, and the possible mechanisms may be related to their ability to promote angiogenesis via an effect on substances such as VEGF.

BACKGROUND

In China, Qishenyiqi Dropping Pill (QSDP), a Chinese medicine formula containing Astragalus membranaceus (Fisch.) Bunge, Salvia miltiorrhiza Bunge, Panax notoginseng (Burkill) F.H.Chen and Dalbergia odorifera T.C.Chen, has been used frequently in traditional folk medicine for treatment of coronary heart diseases (CHD) and heart failure (HF).

OBJECTIVE

Previous study has shown that QSDP has definite therapeutic effects on promoting the heart function on CHD patients. The present study was designed to study the anti-fibrosis effects of QSDP on HF rats and to explore the underlying molecular mechanisms.

METHODS

HF rat model was induced by left anterior descending (LAD) coronary artery ligation. Two-dimensional (2D) echocardiography was adopted to evaluate heart functions. Immunohistochemical (IHC) method and Western-blot were used to detect expression of critical proteins in renin-angiotensin-aldosterone system (RAAS) or arachidonic acid (AA) metabolic pathway.

RESULTS

Heart functions were seriously injured in the model group. Expressions of fibrotic markers, such as collagen Ⅰ, collagen Ⅲ, matrix metallopeptidase 2 (MMP2) and MMP9 were elevated in the model group. RAAS pathway was activated. Interestingly, AA pathway was also up-regulated in the model group and it was down-regulated by angiotensin converting enzyme inhibitors (ACEIs) drug Captopril. Expressions of the important signal-transuding proteins, including NF-κB, JAK1/STAT3 and Akt, all increased remarkably in the model group. Treatment with QSDP could attenuate myocardial fibrosis by inhibiting RAAS-activated pathway, as indicated by decreased angiotensin type 1 receptor (AT1) and increased AT2 expression. Expressions of phospholipase A2 (PLA2), cyclooxygenase 1 (COX1) and COX2 were also down-regulated in the QSDP-treated group. In addition, "therapeutic" QSDP administration seemed to down-regulate expressions of NF-κB, JAK1/ STAT3 and Akt which may play important roles in myocardial fibrosis.

CONCLUSIONS

QSDP can exert anti-fibrosis effect by down-regulating RAAS pathway, and subsequently inhibiting expressions of proteins in AA pathway.

About 300 species and varieties of Astragalus are identified in China, making the identification of the origin of a particular Astragalus species on the consumer market difficult. A molecular genetic approach was developed to identify various species of Astragalus. Although the 5S-rRNA coding sequence is conserved in higher eukaryotes, the spacer domain of the 5S-rRNA gene has great diversity among different species. The 5S-rRNA spacer domain was amplified by polymerase chain reaction (PCR) from the isolated genomic DNA, and the PCR products (approximately 300 bp) covering the 5S-rRNA spacer domain were sequenced. The nucleotide sequences of Astragalus membranaceus, A. membranaceus var. mongholicus, A. lehmannianus, A. hoantchy, and of one closely related species Hedysarum polybotrys (Hongqi), were determined. Diversity in DNA sequence and restriction enzyme mapping among various species was found in their 5S-rRNA spacer domains. This is the first report on the detection of 5S-rRNA spacer region sequence of Astragalus, and the results could be used for genetic identification of Huangqi.

In order to investigate the biochemical mechanism of Dang-Gui Buxue Tang (DBT) involved in its cardioprotective action, the effects of DBT and related preparations on the cellular level of reduced glutathione (GSH) and on susceptibility to menadione-induced toxicity were examined in H9c2 cardiomyocytes. Treatment with herbal extract prepared from the fresh root of Astragalus membranaceus (RAM) or Angelica sinensis (RAS) alone and their combinations (D1:1-D10:1) in varying ratios of RAM to RAS (1:1 to 10:1, respectively) increased cellular GSH in a concentration-dependent manner, with the effect produced by the D5:1 extract, an authentic formula of DBT, being the most potent. The enhancement of cellular GSH was found to correlate positively with the degree of cytoprotection against menadione toxicity. Both GSH-enhancing and cytoprotective effects of DBT were largely abolished by GSH depletion as a result of buthionine sulfoximine (BSO)/phorone treatment. The DBT-induced increase in the cellular GSH level and the associated cytoprotection were also suppressed by the treatment with BSO, an inhibitor of GSH synthesis, or 1,3-bis(2-chloroethyl)-1-nitrosourea, an inhibitor of GSH regeneration. The results indicate that DBT treatment protects against oxidant injury in H9c2 cells, and that the cytoprotective action is causally related to the increase in cellular GSH level, which is likely mediated by the enhancement of GSH synthesis and regeneration.

Success with rIL-2 immunotherapy of human cancer appears to depend on the administration of high doses which are frequently associated with excessive toxicity. Future use of rIL-2 will require certain modifications based on the use of lower doses of rIL-2 without significant loss of antitumor efficacy. We tested in vitro the possibility of potentiating the activity of rIL-2 in terms of LAK cell generation. We hypothesized that co-incubation of LAK cell precursors with a Chinese herbal extract (F3) of Astragalus membranaceus, (an immune modulator currently under study in our laboratory), along with a low concentration of rIL-2, would generate levels of LAK cell activity equivalent to those generated by high concentrations of rIL-2 alone. We found (1) a 10-fold potentiation of rIL-2 activity manifested by tumor cell-killing activity of 80% resulting from LAK cell generation with F3 plus 100 u/ml of rIL-2 versus 76% generated by 1,000 u/ml of rIL-2 alone; (2) a significant reduction in the number of effector LAK cells required for equicytotoxic reaction following LAK cell generation with F3 plus rIL-2 compared to rIL-2 alone. We conclude that potentiation of antitumor activity mediated by rIL-2 in low concentrations is possible by the concomitant use of another immune modulator such as Astragalus membranaceus.

OBJECTIVE

To study the effect of Astragalus membranaceus extract (AME) in regulating the immune function of human peripheral blood immune cells (PBIC) in vitro.

METHODS

Effects of AME on the proliferation activity of peripheral blood mononuclear cells (PBMC) and the tumor cell phagocytosis of peripheral blood adherent monocytes (PBAM) were measured by using 3H-TdR incorporation. Effect of the tumor-killing activity of cytotoxic T-lymphocyte (CTL) was determined by using 51Cr-releasing assay. Effects on production of IgG by peripheral blood B cells (PBBC) and IL-6 by PBAM were tested by means of ELISA, and effect on production of TNF-alpha by PBAM was studied by means of biological method. Besides, the protein elements of AME were analysed by SDS-PAGE.

RESULTS

AME could promote the proliferation of human PBMC, elevate the tumor cell-killing activity of CTL, strengthen the tumor cell phagocytosis and cytokines (TNF-alpha and IL-6) production of PBAM, and promote the IgG production of PBBC. AME contained multiple protein elements.

CONCLUSIONS

AME has effect in enhancing human immuno-function and anti-tumor activity, it could be applied in clinical practice for immuno-modulation and tumor treatment.

The success of adoptive immunotherapy using recombinant interleukin-2 (rIL-2) and lymphokine-activated killer (LAK) cells in several cancers has been hampered by severe toxicity associated with high doses of rIL-2. Methods that reduce the dosage of rIL-2 without loss of clinical efficacy are needed. In this study we determined the in vitro effect of a phytochemical immune modulator, Astragalus membranaceus (AM), and two fractions isolated by high-performance liquid chromatography on the cytotoxicity of rIL-2-generated LAK cells against a murine renal cell carcinoma. Our results indicated a 10-fold potentiation of rIL-2-generated LAK cell cytotoxicity manifested by tumor cell lysis of 88% in the group with 100 U/ml of rIL-2 plus AM versus 86% in the group with 1,000 U/ml of rIL-2 alone. Potentiation was obtained with the purified fractions as well. A significantly reduced number of LAK cells was required to achieve the tumor cytotoxicity after LAK cell generation with rIL-2 plus the phytochemicals as compared with rIL-2 alone. Our data indicate that AM is an effective immune modulator, capable of potentiating in vitro the antitumor activity of rIL-2-generated LAK cells.