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1.
Integr Cancer Ther ; 23: 15347354241242120, 2024.
Article in English | MEDLINE | ID: mdl-38590244

ABSTRACT

OBJECTIVES: To evaluate the effects of Reishimmune-S, a fungal immunomodulatory peptide, on the quality of life (QoL) and natural killer (NK) cell subpopulations in patients receiving adjuvant endocrine therapy (ET) for breast cancer (BC). METHODS: Patients who received adjuvant ET for stage I-III hormone receptor-positive BC without active infection were enrolled in this prospective pilot study. Reishimmune-S was administered sublingually daily for 6 months. QoL scores, circulating immune cell levels, including lymphocyte/NK cell subpopulations, and plasma levels of interleukin (IL)-6 and tumor necrosis factor (TNF)-α were measured at baseline and every 4 weeks. Data were analyzed using linear mixed-effect regression models. RESULTS: Nineteen participants were included in the analyses. One patient with underlying asthma did not complete the study owing to the occurrence of skin rashes 15 days after the initiation of Reishimmune-S. No other adverse events were reported. Reishimmune-S supplementation significantly improved the cognitive function at 3 months and significantly decreased the fatigue and insomnia levels at 3 and 6 months, respectively. There was no significant change in the global health/QoL score between baseline and week 4 of treatment. The proportion of CD19+ lymphocytes was significantly higher at 3 and 6 months, and that of NKG2A+ and NKp30+ NK cells was significantly lower at 6 months than at baseline. In addition, fatigue positively correlated with the proportion of NKp30+ NK cells (ß ± standard error: 24.48 ± 8.75, P = .007 in the mixed-effect model). CONCLUSIONS: Short-term supplementation with Reishimmune-S affected the circulating immune cell composition and exerted positive effects on cognitive function, fatigue, and insomnia in patients with BC undergoing adjuvant ET, providing a potential approach for the management of treatment-related adverse reactions in this patient population.


Subject(s)
Breast Neoplasms , Sleep Initiation and Maintenance Disorders , Humans , Female , Breast Neoplasms/psychology , Quality of Life , Prospective Studies , Pilot Projects , Tumor Necrosis Factor-alpha , Killer Cells, Natural , Dietary Supplements , Fatigue/chemically induced
2.
Sci Rep ; 13(1): 17916, 2023 10 20.
Article in English | MEDLINE | ID: mdl-37864098

ABSTRACT

There is little research about the stress, quality of life (QOL) and gut microbiota in newly diagnosed breast cancer patients. In this study addressing the dearth of research on stress, quality of life (QOL), and gut microbiota in newly diagnosed breast cancer patients, 82 individuals were prospectively observed. Utilizing the Functional Assessment of Chronic Illness Therapy (FACT)-Breast questionnaire to assess health-related quality of life (HRQOL) and the Distress Thermometer (DT) to gauge distress levels, the findings revealed a mean FACT-B score of 104.5, underscoring HRQOL's varied impact. Significantly, 53.7% reported moderate to severe distress, with a mean DT score of 4.43. Further exploration uncovered compelling links between distress levels, FACT-B domains, and microbial composition. Notably, Alcaligenaceae and Sutterella were more abundant in individuals with higher DT scores at the family and genus levels (p = 0.017), while Streptococcaceae at the family level and Streptococcus at the genus level were prevalent in those with lower DT scores (p = 0.028 and p = 0.023, respectively). This study illuminates the intricate interplay of stress, QOL, and gut microbiota in newly diagnosed breast cancer patients, offering valuable insights for potential interventions of biomarker or probiotics aimed at alleviating stress and enhancing QOL in this patient cohort.


Subject(s)
Breast Neoplasms , Gastrointestinal Microbiome , Humans , Female , Quality of Life , Breast Neoplasms/therapy , Stress, Psychological/diagnosis , Patients
4.
J Cancer Res Ther ; 18(5): 1213-1230, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36204866

ABSTRACT

The main contents of the Clinical Practice Guidelines on Image-Guided Thermal Ablation (IGTA) of Primary and Metastatic Lung Tumors (2022 Edition) include the following: epidemiology of primary and metastatic lung tumors; the concepts of the IGTA and common technical features; procedures, indications, contraindications, outcomes evaluation, and related complications of IGTA on primary and metastatic lung tumors; and limitations and future development.


Subject(s)
Ablation Techniques , Catheter Ablation , Hyperthermia, Induced , Lung Neoplasms , Surgery, Computer-Assisted , Ablation Techniques/methods , Catheter Ablation/adverse effects , Catheter Ablation/methods , Humans , Hyperthermia, Induced/methods , Lung Neoplasms/pathology , Practice Guidelines as Topic , Surgery, Computer-Assisted/methods
5.
Int J Mol Sci ; 22(23)2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34884807

ABSTRACT

This study investigated the effects of l-glutamine (Gln) and/or l-leucine (Leu) administration on sepsis-induced skeletal muscle injuries. C57BL/6J mice were subjected to cecal ligation and puncture to induce polymicrobial sepsis and then given an intraperitoneal injection of Gln, Leu, or Gln plus Leu beginning at 1 h after the operation with re-injections every 24 h. All mice were sacrificed on either day 1 or day 4 after the operation. Blood and muscles were collected for analysis of inflammation and oxidative damage-related biomolecules. Results indicated that both Gln and Leu supplementation alleviated sepsis-induced skeletal muscle damage by reducing monocyte infiltration, calpain activity, and mRNA expression levels of inflammatory cytokines and hypoxia-inducible factor-1α. Furthermore, septic mice treated with Gln had higher percentages of blood anti-inflammatory monocytes and muscle M2 macrophages, whereas Leu treatment enhanced the muscle expressions of mitochondrion-related genes. However, there were no synergistic effects when Gln and Leu were simultaneously administered. These findings suggest that both Gln and Leu had prominent abilities to attenuate inflammation and degradation of skeletal muscles in the early and/or late phases of sepsis. Moreover, Gln promoted the switch of leukocytes toward an anti-inflammatory phenotype, while Leu treatment maintained muscle bioenergetic function.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Glutamine/therapeutic use , Leucine/therapeutic use , Muscle, Skeletal/injuries , Sepsis/pathology , Animals , Calpain/metabolism , Cytokines/biosynthesis , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , Inflammation/prevention & control , Macrophages/physiology , Male , Mice , Mice, Inbred C57BL , Monocytes/physiology , Muscle, Skeletal/pathology , Oxidative Stress/drug effects
6.
J Cancer Res Ther ; 17(5): 1141-1156, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34850761

ABSTRACT

The Expert Consensus reviews current literatures and provides clinical practice guidelines for thermal ablation of pulmonary subsolid nodules or ground-glass nodule (GGN). The main contents include the following: (1) clinical evaluation of GGN; (2) procedures, indications, contraindications, outcomes evaluation, and related complications of thermal ablation for GGN; and (3) future development directions.


Subject(s)
Hyperthermia, Induced/methods , Lung Neoplasms/surgery , Multiple Pulmonary Nodules/surgery , Precancerous Conditions/surgery , Solitary Pulmonary Nodule/surgery , Consensus , Expert Testimony , Humans
7.
Nutrients ; 12(4)2020 Apr 14.
Article in English | MEDLINE | ID: mdl-32295272

ABSTRACT

The liver is the main organ responsible for bacterial and endotoxin clearance. Pyroptosis is a form of proinflammatory programmed cell death activated by caspase-1/11 and gasdermin D (GadD). Pyroptosis protects the host against bacterial infection; however, overactive pyroptosis can lead to organ injury. Glutamine (GLN) is a specific amino acid with anti-inflammatory and immunomodulatory properties. This study investigated the effects of GLN pretreatment on liver pyroptosis in a mouse model of polymicrobial sepsis. Mice were assigned to sham, sepsis control (Sepsis-C), and sepsis GLN (Sepsis-G) groups. The sham and Sepsis-C groups were fed the AIN-93G diet. The Sepsis-G group was provided with identical diet components except that part of the casein was replaced by GLN. After feeding the respective diets for 2 weeks, a cecal ligation and puncture (CLP) procedure was performed in the sepsis groups. An antibiotic was administered after CLP. Mice were sacrificed at either 24 or 72 h after CLP. The results showed that sepsis resulted in upregulated liver caspase-1/11 expression. Compared to the Sepsis-C group, the Sepsis-G group had higher liver caspase-11 and NLRP3 gene expressions at 24 h and lower active caspase-1/11 and cleaved GadD protein levels at 72 h after sepsis. Additionally, liver inflammatory cytokine gene expressions had decreased by 72 h post-CLP. The findings suggest that prophylactic administration of GLN initially upregulated liver pyroptosis to eradicate pathogens, yet the process of pyroptosis was suppressed in the late phase of sepsis. This may have beneficially attenuated liver inflammation and injury in an antibiotic-treated septic condition.


Subject(s)
Coinfection/physiopathology , Coinfection/therapy , Dietary Supplements , Glutamine/administration & dosage , Glutamine/pharmacology , Liver/metabolism , Pyroptosis/drug effects , Sepsis/physiopathology , Sepsis/therapy , Animals , Anti-Inflammatory Agents , Caspase 1/genetics , Caspase 1/metabolism , Caspases, Initiator/genetics , Caspases, Initiator/metabolism , Coinfection/metabolism , Disease Models, Animal , Gene Expression/drug effects , Immunologic Factors , Inflammation , Liver/physiopathology , Male , Mice, Inbred C57BL , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Sepsis/metabolism
8.
J Cancer Res Ther ; 14(4): 730-744, 2018.
Article in English | MEDLINE | ID: mdl-29970646

ABSTRACT

Although surgical resection with curative intent is the main therapy for both primary and metastatic lung tumors, about 80% of lung cancers cannot be removed by surgery. Because most patients with unresectable lung cancer only receive limited benefits from traditional radiotherapy and chemotherapy, many novel local treatment modalities have emerged including local ablation therapy. The Minimally Invasive Treatment of Lung Cancer Branch, Professional Committee of Minimally Invasive Treatment of Cancer of the Chinese Anti-Cancer Association and Committee on Tumor Ablations, Chinese College of Interventionalists have organized multidisciplinary experts to develop guidelines for this treatment modality. These guidelines aim at standardizing thermal ablation procedures, describing the indications for candidates, assessing outcomes, and preventing postablation complications.


Subject(s)
Catheter Ablation , Hyperthermia, Induced , Lung Neoplasms/pathology , Lung Neoplasms/therapy , Catheter Ablation/methods , Humans , Hyperthermia, Induced/methods , Lung Neoplasms/diagnostic imaging , Neoplasm Metastasis , Neoplasm Staging , Practice Guidelines as Topic , Surgery, Computer-Assisted , Treatment Outcome
9.
J Surg Oncol ; 118(1): 31-36, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29878378

ABSTRACT

BACKGROUND AND OBJECTIVES: Irreversible electroporation (IRE) is a non-thermal focal therapy that utilizes high voltage electric pulses to permanently rupture the cellular membrane and induce cell death. In this multi-center study, we evaluated the safety and efficacy of IRE in patients with locally advanced pancreatic cancer (LAPC). METHODS: From 2012 to 2015, we performed laparotomic and laparoscopic IRE in a total of 70 patients with stage III LAPC. Either gemcitabine-based or TS-1 (Tegafur, Gimeracil, and Oteracil) chemotherapy was applied for at least 3 months before the IRE. RESULTS: No IRE-related deaths occurred. A median follow-up of 28.1 months showed that six patients (8.6%) experienced local recurrence and 24 (34%) experienced distant progression. The overall median survival from the time of treatment was 22.6 months, and the progression-free survival (PFS) was 15.4 months. The overall survival in the patients who used gemcitabine-based reagents was 19.1 months and that of those who used TS-1 was 28.7 months. The PFS for these two groups were 13.2 months and 26.4 months; the difference is significant. CONCLUSIONS: Our study suggests that IRE is safe and effective for the control of LAPC. We surmise that the addition of IRE to a chemotherapy regimen may provide a survival advantage.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Catheter Ablation/methods , Electrochemotherapy/methods , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/surgery , Adenocarcinoma/drug therapy , Adenocarcinoma/surgery , Chemotherapy, Adjuvant , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Disease-Free Survival , Drug Combinations , Fluorouracil/administration & dosage , Humans , Induction Chemotherapy , Laparotomy/methods , Oxonic Acid/administration & dosage , Pyridines/administration & dosage , Survival Rate , Tegafur/administration & dosage , Gemcitabine
10.
Oncotarget ; 8(3): 4196-4207, 2017 Jan 17.
Article in English | MEDLINE | ID: mdl-27926533

ABSTRACT

Current evidence suggests that oral cancer stem cells (OCSCs) possess high tumorigenic and metastatic properties as well as chemo- and radioresistance. In this study, we demonstrated that andrographolide, the main bioactive component in the medicinal plant Andrographis, significantly reduced oncogenicity and restored radio-sensitivity of ALDH1+CD44+ OCSCs. Mechanistic studies showed that andrographolide treatment increased the expression of microRNA-218 (miR-218), leading to the downregulation of Bmi1. We showed that knockdown of miR-218 in ALDH1-CD44- non-OCSCs enhanced cancer stemness, while silencing of Bmi1 significantly counteracted it. Furthermore, we found tumor growth was reduced in mice bearing xenograft tumors after andrographolide treatment via activation of miR-218/Bmi1 axis. Together, these data demonstrated that the inhibition of tumor aggressiveness in OCSCs by andrographolide was mediated through the upregulation of miR-218, thereby reducing Bmi1 expression. These findings suggest that andrographolide may be a valuable natural compound for anti-CSCs treatment of OSCC.


Subject(s)
Antineoplastic Agents, Phytogenic/administration & dosage , Carcinoma, Squamous Cell/therapy , Diterpenes/administration & dosage , MicroRNAs/genetics , Mouth Neoplasms/therapy , Radiation-Sensitizing Agents/administration & dosage , Animals , Antineoplastic Agents, Phytogenic/pharmacology , Carcinoma, Squamous Cell/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Diterpenes/pharmacology , Gene Expression Regulation, Neoplastic/drug effects , Humans , Mice , Mouth Neoplasms/genetics , Neoplastic Stem Cells/drug effects , Neoplastic Stem Cells/radiation effects , Polycomb Repressive Complex 1/genetics , Radiation-Sensitizing Agents/pharmacology , Xenograft Model Antitumor Assays
11.
Article in English | MEDLINE | ID: mdl-26379739

ABSTRACT

Antrodia camphorata (A. camphorata) is a fungus generally used in Chinese folk medicine for treatment of viral hepatitis and cancer. Our previous study found A. camphorata has neuroprotective properties and could reduce stroke injury in cerebral ischemia animal models. In this study, we sought to investigate the molecular mechanisms of neuroprotective effects of A. camphorata in middle cerebral artery occlusion (MCAO) rats. A selective occlusion of the middle cerebral artery (MCA) with whole blood clots was used to induce ischemic stroke in rats and they were orally treated with A. camphorata (0.25 and 0.75 g/kg/day) alone or combined with aspirin (5 mg/kg/day). To provide insight into the functions of A. camphorata mediated neuroprotection, the expression of Bax, inducible nitric oxide synthase (iNOS), haem oxygenase-1 (HO-1), and activated caspase-3 was determined by Western blot assay. Treatment of aspirin alone significantly reduced the expressions of HO-1 (P < 0.001), iNOS (P < 0.001), and Bax (P < 0.01) in ischemic regions. The reduction of these expressions was more potentiated when rats treated by aspirin combined with A. camphorata (0.75 g/kg/day). Combination treatment also reduced apoptosis as measured by a significant reduction in active caspase-3 expression in the ischemic brain compared to MCAO group (P < 0.01). Moreover, treatment of A. camphorata significantly (P < 0.05) reduced fenton reaction-induced hydroxyl radical (OH(•)) formation at a dose of 40 mg/mL. Taken together, A. camphorata has shown neuroprotective effects in embolic rats, and the molecular mechanisms may correlate with the downregulation of Bax, iNOS, HO-1, and activated caspase-3 and the inhibition of OH(•) signals.

12.
J Cogn Neurosci ; 25(2): 175-87, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22905820

ABSTRACT

Neural responses in early sensory areas are influenced by top-down processing. In the visual system, early visual areas have been shown to actively participate in top-down processing based on their topographical properties. Although it has been suggested that the auditory cortex is involved in top-down control, functional evidence of topographic modulation is still lacking. Here, we show that mental auditory imagery for familiar melodies induces significant activation in the frequency-responsive areas of the primary auditory cortex (PAC). This activation is related to the characteristics of the imagery: when subjects were asked to imagine high-frequency melodies, we observed increased activation in the high- versus low-frequency response area; when the subjects were asked to imagine low-frequency melodies, the opposite was observed. Furthermore, we found that A1 is more closely related to the observed frequency-related modulation than R in tonotopic subfields of the PAC. Our findings suggest that top-down processing in the auditory cortex relies on a mechanism similar to that used in the perception of external auditory stimuli, which is comparable to early visual systems.


Subject(s)
Acoustic Stimulation/methods , Auditory Cortex/physiology , Loudness Perception/physiology , Music , Pitch Perception/physiology , Adult , Association Learning/physiology , Brain Mapping/methods , Female , Humans , Imagination/physiology , Magnetic Resonance Imaging , Male , Neuronal Plasticity/physiology , Visual Perception/physiology , Young Adult
13.
Neuropsychobiology ; 65(3): 153-60, 2012.
Article in English | MEDLINE | ID: mdl-22378299

ABSTRACT

OBJECTIVE: Transcranial focused ultrasound (FUS), with its ability to non-invasively modulate the excitability of region-specific brain areas, is gaining attention as a potential neurotherapeutic modality. The aim of this study was to examine whether or not FUS administered to the brain could alter the extracellular levels of glutamate and γ-aminobutyric acid (GABA), which are representative excitatory and inhibitory amino acid neurotransmitters, respectively. METHODS: FUS, delivered in the form of a train of pulses, was applied to the thalamus of Sprague-Dawley rats transcranially. Glutamate and GABA were directly sampled from the frontal lobe of the rat brain via a direct microdialysis technique before, during, and after the sonication. The dialysate concentrations were determined by high-performance liquid chromatography. RESULTS: The individual levels of the neurotransmitters sampled were normalized to the baseline level for each rat. In terms of the changes in extracellular glutamate levels, there was no difference between the FUS-treated group and the unsonicated control group. However, extracellular GABA levels started to decrease upon sonication and remained reduced (approximately 20% below baseline; repeated-measures ANOVA, p < 0.05, adjusted for multiple comparisons) compared to the control group. CONCLUSION: The ability to modulate region-specific brain activity, along with the present evidence of the ability to modulate neurotransmission, demonstrates the potential utility of FUS as a completely new non-invasive therapeutic modality.


Subject(s)
Extracellular Fluid/metabolism , Thalamus/diagnostic imaging , Thalamus/metabolism , Ultrasonography, Doppler, Transcranial , gamma-Aminobutyric Acid/metabolism , Analysis of Variance , Animals , Chromatography, High Pressure Liquid/methods , Glutamic Acid/metabolism , Male , Rats , Rats, Sprague-Dawley , Time Factors , Ultrasonography, Doppler, Transcranial/instrumentation
14.
Phytomedicine ; 19(3-4): 270-7, 2012 Feb 15.
Article in English | MEDLINE | ID: mdl-22244537

ABSTRACT

There is much evidence indicating that human leukemic cells and monocytes/macrophages synthesize, and secrete, several matrix metalloproteinases (MMPs), and participate in the degradation of extracellular matrix components in tissue lesions. In this study, we investigated the effects and mechanisms of andrographolide, extracted from the herb Andrographis paniculata, on human monocytic MMPs expression and activation. Andrographolide (1-50 µM) exhibited concentration-dependent inhibition of MMP-9 activation, induced by either tumor necrosis factor-α (TNF-α), or lipopolysaccharide (LPS), in THP-1cells. In addition, andrographolide did not present an inhibitory effect on MMP-9 enzymatic activity at a concentration of 50 µM. By contrast, enzyme-linked immunosorbent assay (ELISA) showed that andrographolide partially affect TIMP-1 levels. Western blot analysis showed that both TNF-α, and LPS stimulators attenuated MMP-9 protein expression in a concentration-dependent manner. Using reverse transcription polymerase chain reaction (RT-PCR), we found that andrographolide suppressed expression of MMP-9 messenger RNA. Furthermore, we also found that andrographolide could significantly inhibit the degradation of inhibitor-κB-α (IκB-α) induced by TNF-α. We used electrophoretic mobility shift assay and reporter gene detection to show that andrographolide also markedly inhibited NF-κB signaling, anti-translocation and anti-activation. In conclusion, we demonstrate that andrographolide attenuates MMP-9 expression, and its main mechanism might involve the NF-κB signal pathway. These results provide new opportunities for the development of new anti-inflammatory and leukemic therapies.


Subject(s)
Diterpenes/pharmacology , Matrix Metalloproteinase 9/metabolism , Monocytes/drug effects , NF-kappa B/metabolism , Protease Inhibitors/pharmacology , Andrographis/chemistry , Cell Line , Cell Survival , Dose-Response Relationship, Drug , Electrophoretic Mobility Shift Assay , Enzyme Activation/drug effects , Enzyme-Linked Immunosorbent Assay , Genes, Reporter , Humans , I-kappa B Proteins/metabolism , Lipopolysaccharides/adverse effects , MAP Kinase Signaling System , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase Inhibitors , Monocytes/metabolism , NF-KappaB Inhibitor alpha , NF-kappa B/antagonists & inhibitors , NF-kappa B/genetics , Protein Transport , Proteolysis/drug effects , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Tissue Inhibitor of Metalloproteinase-1/metabolism , Transcriptional Activation/drug effects , Transfection , Tumor Necrosis Factor-alpha/adverse effects
15.
Int J Med Mushrooms ; 13(3): 227-36, 2011.
Article in English | MEDLINE | ID: mdl-22135874

ABSTRACT

Turkey tail medicinal mushroom, Trametes versicolor (TV), is a species with a variety of pharmacological activities. Its intracellular polysaccharopeptides are widely commercialized. Recently, we found a novel TV strain LH-1 in Taiwan and demonstrated that the extracellular polysaccharopeptide (ePSP) of LH-1 obtained from submerged culture exhibits significant immunomodulatory activity. In this in vivo study, we further evaluated the safety of orally administered LH-1 ePSP using both male and female ICR mice. The LH-1 ePSP was orally administered to mice at levels of 0 (water), 100 (low dose), 500 (medium dose), or 1000 mg/kg/day (high dose) for 28 days. Clinical observations, growth, food consumption, histopathological examination, and clinical biochemical analyses revealed no adverse effects of LH-1 ePSP in mice. There were no significant differences in the results of target organ weights, hematological analyses, and urinalysis examination among groups. However, male mice that ingested high doses of LH-1 ePSP tended to have decreased lung weights and platelet numbers. In conclusion, the results of the present study suggested that oral administration of LH-1 ePSP for 28 days is accompanied by no obvious signs of toxicity. The lack of toxicity supports the potential use of LH-1 ePSP as a food or dietary supplement.


Subject(s)
Proteoglycans/toxicity , Trametes/chemistry , Administration, Oral , Animals , Blood Cell Count , Blood Chemical Analysis , Body Weight/drug effects , Dose-Response Relationship, Drug , Drug Evaluation, Preclinical , Female , Immunomodulation/drug effects , Male , Mice , Mice, Inbred ICR , Organ Size/drug effects , Proteoglycans/administration & dosage , Random Allocation , Taiwan , Time Factors , Toxicity Tests , Trametes/classification , Trametes/isolation & purification , Urinalysis
16.
Neurosci Lett ; 454(1): 72-5, 2009 Apr 17.
Article in English | MEDLINE | ID: mdl-19429057

ABSTRACT

Stevioside is a dietary supplement widely used as a sweetener to prevent hyperglycemic disorders. However, the action mechanisms of this substance for glucose homeostasis remain obscure. In the present study, a dose-related plasma glucose reduction was observed in Wistar rats receiving intraperitoneally injections of stevioside. Similar to the regulation of glucose metabolism by the activation of mu opioid receptors, this action of stevioside was reversed by naloxonazine under the blockade of mu opioid receptors. We also found that stevioside increased glycogen synthesis in isolated hepatocytes, which was concentration-dependently blocked by naloxonazine. Stevioside did not modify the plasma beta-endorphin levels in Wistar rats but it directly increased the phosphorylation of mu opioid receptors in Chinese hamster ovary cells transfected with mu opioid receptors. Unlike morphine, chronic administration of stevioside did not induce the withdrawal signs in mice. Furthermore, stevioside by intraperitoneal injections did not influence the feeding behaviors of rats. By contrast, intracerebroventricular injections of stevioside increased the rats' food intake, which was also inhibited by pretreatment with naloxonazine. These results showed that it is difficult for stevioside to enter the brain. Stevioside has the ability to activate peripheral mu opioid receptors for lowering plasma glucose and to increase glycogen synthesis in liver. Thus, the stimulation of peripheral mu opioid receptors is responsible for the action of stevioside in the regulation of glucose homeostasis.


Subject(s)
Diterpenes, Kaurane/pharmacology , Glucosides/pharmacology , Receptors, Opioid, mu/drug effects , Sweetening Agents/pharmacology , Animals , Blood Glucose/drug effects , CHO Cells , Cricetinae , Cricetulus , Eating/drug effects , Feeding Behavior/drug effects , Glycogen/metabolism , Hepatocytes/drug effects , Mice , Phosphorylation , Rats , Rats, Wistar , Receptors, Opioid, mu/metabolism
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