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1.
Nature ; 630(8015): 70-76, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38811730

ABSTRACT

Colour centres in diamond have emerged as a leading solid-state platform for advancing quantum technologies, satisfying the DiVincenzo criteria1 and recently achieving quantum advantage in secret key distribution2. Blueprint studies3-5 indicate that general-purpose quantum computing using local quantum communication networks will require millions of physical qubits to encode thousands of logical qubits, presenting an open scalability challenge. Here we introduce a modular quantum system-on-chip (QSoC) architecture that integrates thousands of individually addressable tin-vacancy spin qubits in two-dimensional arrays of quantum microchiplets into an application-specific integrated circuit designed for cryogenic control. We demonstrate crucial fabrication steps and architectural subcomponents, including QSoC transfer by means of a 'lock-and-release' method for large-scale heterogeneous integration, high-throughput spin-qubit calibration and spectral tuning, and efficient spin state preparation and measurement. This QSoC architecture supports full connectivity for quantum memory arrays by spectral tuning across spin-photon frequency channels. Design studies building on these measurements indicate further scaling potential by means of increased qubit density, larger QSoC active regions and optical networking across QSoC modules.

2.
Fitoterapia ; 175: 105924, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38537886

ABSTRACT

Alzheimer's disease (AD) is a progressive neurodegenerative disease, and accumulating evidence suggested that proteostatic imbalance is a key feature of the disease. Traditional Chinese medicine exhibits a multi-target therapeutic effect, making it highly suitable for addressing protein homeostasis imbalance in AD. Dendrobium officinale is a traditional Chinese herbs commonly used as tonic agent in China. In this study, we investigated protection effects of D. officinale phenolic extract (SH-F) and examined its underlying mechanisms by using transgenic Caenorhabditis elegans models. We found that treatment with SH-F (50 µg/mL) alleviated Aß and tau protein toxicity in worms, and also reduced aggregation of polyglutamine proteins to help maintain proteostasis. RNA sequencing results showed that SH-F treatment significantly affected the proteolytic process and autophagy-lysosomal pathway. Furthermore, we confirmed that SH-F showing maintainance of proteostasis was dependent on bec-1 by qRT-PCR analysis and RNAi methods. Finally, we identified active components of SH-F by LC-MS method, and found the five major compounds including koaburaside, tyramine dihydroferulate, N-p-trans-coumaroyltyramine, naringenin and isolariciresinol are the main bioactive components responsible for the anti-AD activity of SH-F. Our findings provide new insights to develop a treatment strategy for AD by targeting proteostasis, and SH-F could be an alternative drug for the treatment of AD.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Autophagy , Caenorhabditis elegans , Dendrobium , Disease Models, Animal , Plant Extracts , Proteostasis , Animals , Caenorhabditis elegans/drug effects , Alzheimer Disease/drug therapy , Dendrobium/chemistry , Proteostasis/drug effects , Autophagy/drug effects , Amyloid beta-Peptides/metabolism , Plant Extracts/pharmacology , Animals, Genetically Modified , tau Proteins/metabolism , Phenols/pharmacology , Phenols/isolation & purification , Flavanones/pharmacology , Drugs, Chinese Herbal/pharmacology , Phytochemicals/pharmacology , Phytochemicals/isolation & purification
3.
Foods ; 9(1)2020 Jan 19.
Article in English | MEDLINE | ID: mdl-31963907

ABSTRACT

Consumer acceptance of synbiotics, which are synergistic combinations of probiotics and their prebiotic substrates, continues to expand in the functional food category. This research aimed at evaluating the effect of antibacterial manuka honey on the probiotic growth and sensory characteristics of potentially synbiotic yogurts manufactured with Lactobacillus reuteri DPC16. Probiotic viable count in yogurts with 5% w/v Manuka honey (Blend, UMFTM 18+, AMFTM 15+ and AMFTM 20+) was evaluated by the spread plate method over the refrigerated storage period of three weeks. A panel of 102 consumers preferred the yogurt made with invert syrup over the manuka honey variants, and the unsweetened control was least liked overall. Invert syrup yogurt was also the most effective in promoting the growth of the probiotic lactobacilli. However, the honey-sweetened yogurts had a more favourable fermentation metabolite profile, especially the lactic and propionic acids, as estimated by nuclear magnetic resonance (NMR) analyses. The probiotic counts in AMFTM 15+ manuka honey yogurt (7 log cfu/mL) were significantly higher than the other honey yogurt types (Manuka Blend and UMFTM 18+) and above the recommended threshold levels. The combination thus can be developed as a synbiotic functional food by further improving the sensory and physicochemical properties such as texture, apparent viscosity and water holding capacity.

4.
Int Immunopharmacol ; 6(3): 499-508, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16428086

ABSTRACT

Many herbal medicines are widely used as immuno-modulators in Asian countries. Ganoderma lucidum (Lingzhi) is one of the most commonly used herbs in Asia and preclinical studies have established that the polysaccharide fractions of G. lucidum have potent immuno-modulating effects. However, clinical evidence for this is scanty. The present open-labeled study aimed to evaluate the effects of G. lucidum polysaccharides on selected immune functions in patients with advanced colorectal cancer. Forty-seven patients were enrolled and treated with oral G. lucidum at 5.4 g/day for 12 weeks. Selected immune parameters were monitored using various immunological methods throughout the study. In 41 assessable cancer patients, treatment with G. lucidum tended to increase mitogenic reactivity to phytohemagglutinin, counts of CD3, CD4, CD8 and CD56 lymphocytes, plasma concentrations of interleukin (IL)-2, IL-6 and interferon (IFN)-gamma, and NK activity, whereas plasma concentrations of IL-1 and tumor necrosis factor (TNF)-alpha were decreased. For all of these parameters, no statistical significance was observed when a comparison was conducted between baseline and those values after a 12-week treatment with G. lucidum. The changes of IL-1 were correlated with those for IL-6, IFN-gamma, CD3, CD4, CD8 and NK activity (p<0.05) and IL-2 changes were correlated with those for IL-6, CD8 and NK activity. The results indicate that G. lucidum may have potential immuno-modulating effect in patients with advanced colorectal cancer. Further studies are needed to explore the benefits and safety of G. lucidum in cancer patients.


Subject(s)
Colorectal Neoplasms/immunology , Colorectal Neoplasms/therapy , Drugs, Chinese Herbal/pharmacology , Monitoring, Immunologic , Polysaccharides/pharmacology , Adult , Aged , Cells, Cultured , Colorectal Neoplasms/pathology , Cytokines/blood , Female , Humans , K562 Cells , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Lymphocyte Count , Lymphocyte Subsets/drug effects , Lymphocyte Subsets/immunology , Lymphocyte Subsets/metabolism , Male , Middle Aged , Mitogens/pharmacology , Phytohemagglutinins/pharmacology , Reishi
5.
J Med Food ; 8(2): 159-68, 2005.
Article in English | MEDLINE | ID: mdl-16117607

ABSTRACT

Preclinical studies have established that the polysaccharide fractions of Ganoderma lucidum have potential antitumor activity. Recent clinical studies have demonstrated that G. lucidum polysaccharides enhance host immune functions [e.g., enhanced natural killer (NK) cell activity] in patients with advanced solid tumors, although an objective response was not observed. This open-label study aimed to evaluate the effects of water-soluble G. lucidum polysaccharides (Ganopoly, Encore International Corp., Auckland, New Zealand) on immune functions in patients with advanced lung cancer. Thirty-six patients were enrolled and treated with 5.4 g/day Ganopoly for 12 weeks. In the 30 cancer patients who completed the trial, treatment with Ganopoly did not significantly alter the mean mitogenic reactivity to phytohemagglutinin, mean counts of CD3, CD4, CD8, and CD56, mean plasma concentrations of interleukin (IL)-2, IL-6, and interferon (IFN)-gamma, or NK activity in the patients, but the results were significantly variable. However, some cancer patients demonstrated markedly modulated immune functions. The changes in IL-1 were correlated with those for IL-6, IFN-gamma, CD3, CD8, and NK activity (P < .05), and IL-2 changes were correlated with those for IL-6, CD8, and NK activity. The results suggest that subgroups of cancer patients might be responsive to Ganopoly in combination with chemotherapy/radiotherapy. Further studies are needed to explore the efficacy and safety of Ganopoly used alone or in combination with chemotherapy/radiotherapy in lung cancer patients.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Phytotherapy , Polysaccharides/pharmacology , Reishi/chemistry , Administration, Oral , Adult , Aged , Antineoplastic Agents, Phytogenic/pharmacology , Drugs, Chinese Herbal/pharmacology , Female , Humans , Immunity, Cellular/drug effects , Immunity, Cellular/immunology , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Lung Neoplasms/immunology , Lymphocyte Activation/drug effects , Lymphocyte Activation/immunology , Lymphocyte Count , Lymphocyte Subsets , Male , Middle Aged , Polysaccharides/therapeutic use , Safety , Treatment Outcome
6.
Immunol Invest ; 34(2): 171-98, 2005.
Article in English | MEDLINE | ID: mdl-15921158

ABSTRACT

Ganopoly is an aqueous polysaccharide fraction extracted from G. lucidum by patented biochemical technique and has been marketed as an over-the-counter product for chronic diseases including cancer and hepatopathy in many Asian countries. This study was undertaken to explore the anti-tumour effect and the underlying mechanisms of Ganopoly in mice and human tumor cell lines. The maximum tolerated dose (MTD) of Ganopoly in mice was estimated to be 100 mg/kg from a pilot study. Treatment of mice with oral Ganopoly for 10 days significantly reduced the tumour weight of sarcoma-180 in a dose-dependent manner, with inhibition rates of 32.3, 48.2 and 84.9% and growth delays of 1.5, 3.5, and 13.1 days at 20, 50, and 100 mg/kg, respectively. Incubation of Ganopoly at 0.05-1.0 mg/ml for 48 hours showed little or negligible cytotoxicity against human tumor CaSki, SiHa, Hep3B, HepG2, HCT116 HT29, and MCF7 cells in vitro. In contrast, 10 mg/ml of Ganopoly caused significant cytotoxicity in all tumour cells tested except MCF7, with marked apoptotic effect observed in CaSki, HepG2, and HCT116 cells, as indicated by nuclear staining and DNA fragmentation. In addition, Ganopoly enhanced concanavalin A-stimulated proliferation of murine splenocytes by 35.3% at 10 mg/ml, and stimulated the production of nitric oxide in thioglycollate-primed murine peritoneal macrophages in a concentration-dependent manner over 0.05-10 mg/ml. Addition of Ganopoly at 1 mg/ ml to murine peritoneal macrophages also potentiated lipopolysaccharide-induced nitric oxide production by 64.2%. Treatment of healthy mice or mice bearing sarsoma-180 with oral Ganopoly over 20-100 mg/kg for 7 day significantly increased the expression of both TNF-alpha and IFN-gamma (at both mRNA and protein levels) in splenocytes in a dose-dependent manner. Moreover, treatment of Ganopoly over 20-100 mg/kg significantly increased cytotoxic T lymphocyte cytotoxicity and NK activity in mice. The overall findings indicated that Ganopoly had antitumor activity with a broad spectrum of immuno-modulating activities and may represent a novel promising immunotherapeutic agent in cancer treatment.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Drugs, Chinese Herbal/pharmacology , Polysaccharides/pharmacology , Reishi/chemistry , Sarcoma, Experimental/drug therapy , Animals , Antineoplastic Agents, Phytogenic/therapeutic use , Apoptosis , Cell Line, Tumor , Cytokines/biosynthesis , Drug Evaluation, Preclinical , Drugs, Chinese Herbal/therapeutic use , Humans , Immunologic Factors/therapeutic use , Interferon-gamma/biosynthesis , Killer Cells, Natural/immunology , Macrophages, Peritoneal/drug effects , Macrophages, Peritoneal/metabolism , Male , Mice , Nitric Oxide/biosynthesis , Nitric Oxide/blood , Polysaccharides/isolation & purification , Polysaccharides/therapeutic use , Sarcoma, Experimental/blood , Sarcoma, Experimental/pathology , Spleen/drug effects , Spleen/metabolism , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/biosynthesis
7.
J Med Food ; 8(1): 53-8, 2005.
Article in English | MEDLINE | ID: mdl-15857210

ABSTRACT

Ganoderma lucidum has been widely used to treat various diseases, including cancer, diabetes, and neurasthenia in many Asian countries. This randomized, double-blind, placebo-controlled parallel study aimed to investigate the efficacy and safety of a polysaccharide extract of G. lucidum (Ganopoly) in Chinese patients with neurasthenia. One hundred thirty-two patients with neurasthenia according to the diagnosis criteria of the 10th International Classification of Diseases were included in this study. Written consents were obtained from the patients, and the study was conducted in accordance with Good Clinical Practice guidelines. Patients were randomized to receive Ganopoly or placebo orally at 1,800 mg three times a day for 8 weeks. Efficacy assessments comprised the Clinical Global Impression (CGI) improvement of severity scale and the Visual Analogues Scales for the sense of fatigue and well-being. In 123 assessable patients in two treatment groups at the end of the study, Ganopoly treatment for 8 weeks resulted in significantly lower scores after 8 weeks in the CGI severity score and sense of fatigue, with a respective reduction of 15.5% and 28.3% from baseline, whereas the reductions in the placebo group were 4.9% and 20.1%, respectively. The score at day 56 in the sense of well-being increased from baseline to 38.7% in the Ganopoly group compared with 29.7% in the placebo group. The distribution of the five possible outcomes from very much improved to minimally worse was significantly different (X (2) = 10.55; df = 4; P = .0322) after treatment with Ganopoly or placebo. There was a percentage of 51.6% (32 of 62) in the Ganopoly group rated as more than minimally improved compared with 24.6% (15 of 61) in the placebo group (X (2) = 9.51; df = 1; P = .002). Ganopoly was well tolerated in the study patients. These findings indicated that Ganopoly was significantly superior to placebo with respect to the clinical improvement of symptoms in neurasthenia.


Subject(s)
Drugs, Chinese Herbal/therapeutic use , Neurasthenia/drug therapy , Polysaccharides/therapeutic use , Reishi/chemistry , Administration, Oral , Adolescent , Adult , Aged , Double-Blind Method , Drugs, Chinese Herbal/pharmacology , Female , Humans , Male , Middle Aged , Placebos , Polysaccharides/pharmacology , Safety , Severity of Illness Index , Treatment Outcome
8.
Life Sci ; 74(8): 935-68, 2004 Jan 09.
Article in English | MEDLINE | ID: mdl-14672753

ABSTRACT

It has been well established that the formation of reactive metabolites of drugs is associated with drug toxicity. Similarly, there are accumulating data suggesting the role of the formation of reactive metabolites/intermediates through bioactivation in herbal toxicity and carcinogenicity. It has been hypothesized that the resultant reactive metabolites following herbal bioactivation covalently bind to cellular proteins and DNA, leading to toxicity via multiple mechanisms such as direct cytotoxicity, oncogene activation, and hypersensitivity reactions. This is exemplified by aristolochic acids present in Aristolochia spp, undergoing reduction of the nitro group by hepatic cytochrome P450 (CYP1A1/2) or peroxidases in extrahepatic tissues to reactive cyclic nitrenium ion. The latter was capable of reacting with DNA and proteins, resulting in activation of H-ras oncogene, gene mutation and finally carcinogenesis. Other examples are pulegone present in essential oils from many mint species; and teucrin A, a diterpenoid found in germander (Teuchrium chamaedrys) used as an adjuvant to slimming diets. Extensive pulegone metabolism generated p-cresol that was a glutathione depletory, and the furan ring of the diterpenoids in germander was oxidized by CYP3A4 to reactive epoxide which reacts with proteins such as CYP3A and epoxide hydrolase. On the other hand, some herbal/dietary constituents were shown to form reactive intermediates capable of irreversibly inhibiting various CYPs. The resultant metabolites lead to CYP inactivation by chemical modification of the heme, the apoprotein, or both as a result of covalent binding of modified heme to the apoprotein. Some examples include bergamottin, a furanocoumarin of grapefruit juice; capsaicin from chili peppers; glabridin, an isoflavan from licorice root; isothiocyanates found in all cruciferous vegetables; oleuropein rich in olive oil; dially sulfone found in garlic; and resveratrol, a constituent of red wine. CYPs have been known to metabolize more than 95% therapeutic drugs and activate a number of procarcinogens as well. Therefore, mechanism-based inhibition of CYPs may provide an explanation for some reported herb-drug interactions and chemopreventive activity of herbs. Due to the wide use and easy availability of herbal medicines, there is increasing concern about herbal toxicity. The safety and quality of herbal medicine should be ensured through greater research, pharmacovigilance, greater regulatory control and better communication between patients and health professionals.


Subject(s)
Biotransformation/drug effects , Plant Preparations/pharmacology , Plant Preparations/toxicity , Animals , Anticarcinogenic Agents/pharmacology , Aristolochic Acids/toxicity , Cyclohexane Monoterpenes , Cytochrome P-450 Enzyme Inhibitors , Drug Interactions , Humans , Monoterpenes/toxicity , Teucrium/toxicity
9.
J Med Food ; 7(4): 417-21, 2004.
Article in English | MEDLINE | ID: mdl-15671683

ABSTRACT

The polysaccharide (PS) fractions from several medicinal herbs have been reported to have anti-ulcer effects against experimental ulcers in the rat. The water-soluble PS fractions from Ganoderma lucidum (Reishi mushroom) have been shown to inhibit indomethacin-induced gastric mucosal lesions in rats. This study aimed to investigate the effect of the PS fraction from G. lucidum on the healing of gastric ulcers induced by acetic acid in the rat and to elucidate the underlying mechanisms involved. The abdomen of rats was incised, and the stomach was treated with 10 M acetic acid (100 microL) for 1 minute, and then treated with G. lucidum PS (0.1, 0.5, or 1.0 g/kg) intragastrically, once a day for 14 consecutive days. The results indicated that the oral administration of G. lucidum PS at 0.5 and 1.0 g/kg for 2 weeks caused a significant acceleration of ulcer healing by 40.1% and 55.9%, respectively. In the mechanistic studies, additional rats were treated with 10 M acetic acid to induce acute ulcers, and then treated with G. lucidum PS (1.0 g/kg) for 3, 7, 10, or 14 days. Exposure of the rat stomach to acetic acid led to decreased mucus and increased prostaglandin levels. Treatment with G. lucidum PS at 1.0 g/kg significantly (P < .05) suppressed or restored the decreased gastric mucus levels and increased gastric prostaglandin concentrations compared with the control group. These results indicates that G. lucidum PS is an active component with healing efficacy on acetic acid-induced ulcers in the rat, which may represent a useful herbal preparation for the prevention and treatment of peptic ulcers.


Subject(s)
Anti-Ulcer Agents/therapeutic use , Phytotherapy , Polysaccharides/therapeutic use , Reishi/chemistry , Stomach Ulcer/drug therapy , Wound Healing/drug effects , Acetic Acid/pharmacology , Administration, Oral , Animals , Disease Models, Animal , Dose-Response Relationship, Drug , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Male , Plant Extracts/therapeutic use , Random Allocation , Rats , Rats, Wistar , Stomach Ulcer/chemically induced , Stomach Ulcer/pathology , Wound Healing/physiology
10.
Immunol Invest ; 32(3): 201-15, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12916709

ABSTRACT

Preclinical studies have established that the Ganoderma lucidum polysaccharide (GLPS) fractions have potent anti-tumor activity, which has been associated with the immuno-stimulating effects of GLPS. However, it is unclear whether GLPS has immuno-modulating effects in humans in vivo. This study aimed to investigate the effects of Ganopoly, the polysaccharides fractions extracted from G. lucidum, on the immune function of advanced-stage cancer patients. Thirty-four advance-stage cancer patients were entered onto this study, and treated with 1800 mg Ganopoly, three times daily orally before meals for 12 weeks. Immune parameters (cytokines, T cell subsets, mitotic response to phytohemagglutinin (PHA) and natural killer activity) were compared between baseline and after 12-week treatment. Thirty patients are assessable for their immune functions. Treatment of Ganopoly for 12 weeks resulted in a significant (P < 0.05) increase in the mean plasma concentrations of interleukin (IL-2), IL-6, and interferon (IFN)-gamma, whereas the levels of IL-1 and tumor necrosis factor (TNF-alpha) were significantly (P < 0.05) decreased. A marked variability among patients with advanced-stage cancer was observed in the numbers of each lymphocyte subset at baseline. The mean absolute number of CD56+ cells was significantly (P < 0.05) increased after 12-week treatment of Ganopoly, whereas the numbers of CD3+, CD4+, and CD8+ were just marginally increased compared to baseline levels, with the CD4:CD8 T cell ratios unchanged. PHA responses after 12-week treatment with Ganopoly were enhanced in most patients, when compared to pretreatment baselines (P < 0.05). In addition, Ganopoly treatment resulted in a significant increase (P < 0.05) in the mean NK activity compared to baselines (34.5 +/- 11.8% vs 26.6 +/- 8.3%). The present study indicates that Ganopoly enhanced the immune responses in patients with advanced-stage cancer. Clinical evaluations of response and toxicity are ongoing.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Cytokines/blood , Immunity, Cellular/drug effects , Neoplasms/immunology , Polysaccharides/pharmacology , Reishi , Adult , Aged , Antineoplastic Agents, Phytogenic/therapeutic use , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Humans , Immunophenotyping , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Lymphocyte Activation , Lymphocyte Count , Lymphocyte Subsets , Middle Aged , Neoplasms/drug therapy , Phytotherapy , Polysaccharides/immunology , Polysaccharides/therapeutic use
11.
Drug Metab Rev ; 35(1): 35-98, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12635815

ABSTRACT

A resurgence in the use of medical herbs in the Western world, and the co-use of modern and traditional therapies is becoming more common. Thus there is the potential for both pharmacokinetic and pharmacodynamic herb-drug interactions. For example, systems such as the cytochrome P450 (CYP) may be particularly vulnerable to modulation by the multiple active constituents of herbs, as it is well known that the CYPs are subject to induction and inhibition by exposure to a wide variety of xenobiotics. Using in vitro, in silico, and in vivo approaches, many herbs and natural compounds isolated from herbs have been identified as substrates, inhibitors, and/or inducers of various CYP enzymes. For example, St. John's wort is a potent inducer of CYP3A4, which is mediated by activating the orphan pregnane X receptor. It also contains ingredients that inhibit CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4. Many other common medicinal herbs also exhibited inducing or inhibiting effects on the CYP system, with the latter being competitive, noncompetitive, or mechanism-based. It appears that the regulation of CYPs by herbal products complex, depending on the herb type, their administration dose and route, the target organ and species. Due to the difficulties in identifying the active constituents responsible for the modulation of CYP enzymes, prediction of herb-drug metabolic interactions is difficult. However, herb-CYP interactions may have important clinical and toxicological consequences. For example, induction of CYP3A4 by St. John's wort may partly provide an explanation for the enhanced plasma clearance of a number of drugs, such as cyclosporine and innadivir, which are known substrates of CYP3A4, although other mechanisms including modulation of gastric absorption and drug transporters cannot be ruled out. In contrast, many organosulfur compounds, such as diallyl sulfide from garlic, are potent inhibitors of CYP2E1; this may provide an explanation for garlic's chemoproventive effects, as many mutagens require activation by CYP2E1. Therefore, known or potential herb-CYP interactions exist, and further studies on their clinical and toxicological roles are warranted. Given that increasing numbers of people are exposed to a number of herbal preparations that contain many constituents with potential of CYP modulation, high-throughput screening assays should be developed to explore herb-CYP interactions.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Plants, Medicinal/chemistry , Plants, Medicinal/metabolism , Animals , Herb-Drug Interactions , Humans
12.
Life Sci ; 72(6): 731-45, 2002 Dec 27.
Article in English | MEDLINE | ID: mdl-12467913

ABSTRACT

Many cytokines, in particular tumor necrosis factor (TNF)-alpha have been known to play an important role in the pathogenesis of gastric mucosal lesions caused by various factors such as drugs and Helicobacter pylori infection. Our previous studies have shown that the polysaccharide fractions isolated from the fruiting bodies of Ganoderma lucidum (GLPS) prevented indomethacin- and acetic acid-induced gastric mucosal lesions in the rat. However, the mechanisms remain unclear. This study aimed to investigate whether GLPS had a direct mucosal healing effect in the indomethacin-treated rat, and to explore the possible mechanisms by determining the gastric mucosal mRNA and protein levels of TNF-alpha and ornithine decarboxylase (ODC) activity. In addition, the effects of GLPS on the cellular proliferation, ODC and c-Myc protein expression and mucus synthesis in the rat gastric cell culture (RGM-1) were examined. The present study demonstrated that GLPS at 250 and 500 mg/kg by intragastric input caused ulcer-healing effect in the rat; this was accompanied with a significant suppression of TNF-alpha gene expression, but with an increased ODC activity. In RGM-1 cells, GLPS at 0.05, 0.25 and 1.0 mg/ml significantly enhanced [3H]thymidine incorporation and ODC activity in a concentration-dependent manner. However, these effects were abrogated by the addition of the ODC inhibitor, DL-alpha-difluoromethyl-ornithine (DFMO). GLPS at 0.25-1.0 mg/ml also increased mucus synthesis, as indicated by the increased D-[6-3H]glucosamine incorporation in RGM-1 cells. Furthermore, GLPS at 0.05-1.0 mg/ml increased the c-Myc protein expression. These findings indicated that GLPS produced a mucosal healing effect in the rat model, perhaps due partly to the suppression of TNF-alpha and induction of c-myc and ODC gene.


Subject(s)
Anti-Ulcer Agents/therapeutic use , Drugs, Chinese Herbal , Polysaccharides/therapeutic use , Reishi , Stomach Ulcer/drug therapy , Animals , Anti-Ulcer Agents/isolation & purification , Cells, Cultured , Disease Models, Animal , Dose-Response Relationship, Drug , Gastric Mucosa/drug effects , Gastric Mucosa/metabolism , Gastric Mucosa/pathology , Indomethacin/toxicity , Male , Ornithine Decarboxylase/metabolism , Plant Extracts/therapeutic use , Polysaccharides/isolation & purification , RNA, Messenger/metabolism , Rats , Rats, Inbred WKY , Reishi/chemistry , Stomach Ulcer/chemically induced , Stomach Ulcer/metabolism , Tumor Necrosis Factor-alpha/metabolism , Wound Healing/drug effects , Wound Healing/physiology
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