RESUMEN
SCOPE: The previous in vivo studies show Ganoderma atrum polysaccharide (PSG-F2 ) has a protective effect against the acrylamide (AA)-induced intestinal oxidative damage in rats. Now, this study aims to explore the protective mechanism with IEC-6 cell model. METHODS AND RESULTS: Based on RNA Sequencing (RNA-Seq), the study screens MAPK signaling pathway as one of the most crucial pathways for pretreatment with PSG-F2 against AA-induced damage in IEC-6 cells. In total, six key MAPK signaling pathway-related proteins (p-P38/P38, p-ERK/ERK, and p-JNK/JNK), and three tight junction key proteins (Zonula Occludens protein-1, Claudin-1, and Occludin) are detected by Western blot and immunofluorescence, which verify the RNA-Seq data. Moreover, PD98059 interference inhibits critical proteins in the MAPK signaling pathway, thus uncovering the precise molecular mechanisms of MAPK/ERK signaling pathway involve in the protective effects of PSG-F2 against AA-induced intestinal barrier damage. CONCLUSION: These findings confirm that PSG-F2 can be used as a daily dietary supplement to protect the intestinal cells from damage caused by thermal processing hazards AA.
Asunto(s)
Acrilamida , Ganoderma , Ratas , Animales , Acrilamida/toxicidad , Uniones Estrechas , Polisacáridos/farmacología , Estrés OxidativoRESUMEN
The potential mechanism for the protective effect of Ganoderma atrum (G. atrum) polysaccharide (PSG-1) on acrylamide (AA) induced intestinal damage in mice was explored. Results showed that PSG-1 pretreatment prevented AA-induced injury by decreasing intestinal permeability and serum D-lactate acid (D-Lac) levels and increasing the number of small intestinal goblet cells and IgA secreting cells. In addition, PSG-1 pretreatment effectively reduced malondialdehyde (MDA) level and raised superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) activities in the intestine. Furthermore, PSG-1 administration decreased the levels of pro-inflammatory factors including IL-1ß, TNF-α, and IL-6, while the anti-inflammatory factor IL-10 was elevated. Meanwhile, PSG-1 could increase the performance of tight junction (TJ) proteins such as Occludin, Claudin-1 and ZO-1. Moreover, according to the isobaric tag for relative and absolute quantitation (iTRAQ) and Western blot results, PSG-1 could reduce AA-induced intestinal injury through TLR4/MyD88/NF-κB signaling pathway. Overall, the present study suggested that PSG-1 protected intestinal permeability and barrier function in mice via reducing inflammation and oxidative stress, and effectively prevented AA-induced intestinal injury in mice.
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Ganoderma , FN-kappa B , Animales , Ratones , Acrilamida , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Glutatión/metabolismo , Factor 88 de Diferenciación Mieloide/metabolismo , FN-kappa B/metabolismo , Polisacáridos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
The modern rise in type 2 diabetes mellitus (T2DM) and its correlation to commensal microbiota have elicited global concern about the patterns of microbial action in the host. With the exception of that linked to gut, microbiota were also colonized in pancreas, oral, and lung, contributing to the physiopathology of T2DM. In this study, we aimed to explore the protective effects of Ganoderma atrum polysaccharide (PSG) and White Hyacinth Bean polysaccharide (WHBP) on the intestine, pancreas, oral, and lung microbiota in T2DM rats. Here we showed that, despite capacities of polysaccharides that exerted similar protective effects on hyperglycemia, dyslipidemia, insulin resistance and dysbacteriosis in T2DM rats, PSG and WHBP were able to be characterized by their own "target" bacteria, which could be proposed for activity-fingerprinting of polysaccharide species. Furthermore, we found a mutual bacteria spectrum in the pancreas and lung, and most bacteria could be tracked to oral or gut samples. Notably, the overlapping areas of the microbiota profile between organs (pancreas, lung) and saliva were more than in the gut, suggesting that a saliva sample was also of interest to serve as a "telltale sign" for judging pancreatic injury. Together, these microbiota interactions provided a new potential to harvest alternative samples for disease surveillance. Meanwhile, polysaccharides had anti-T2DM abilities, which could be distinguished by their own characteristic bacteria.
Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Microbiota , Ratas , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Polisacáridos/farmacología , Páncreas , PulmónRESUMEN
The aim of this study was to investigate the protective effect and underlying mechanisms of Ganoderma atrum polysaccharide (PSG-1) on cyclophosphamide (Cy)-induced intestinal mucosal dysfunction in mice. Results showed that PSG-1 promoted the formation of IgA-secreting cells, modulated sIgA, IgE, IgG, IgM secretion, and improved TLR-2, TLR-4, TLR-6 mRNA levels while these factors were suppressed after Cy treatment. CD4+ and CD8+ T cell numbers were also elevated by PSG-1. Cytokines including IFN-γ, TNF-α, IL-2, IL-12p70, IL-4, IL-1ß, IL-17, IL-21, IL-23, TGF-ß3 and transcription factors including T-bet, GATA-3, RORγt, Foxp3 increased after PSG-1 administration. Besides, PSG-1 reversed goblet cell numbers, and upregulated tight junction proteins like ZO-1, occludin and claudin-1 in immunosuppressed mice. Apart from these, the autophagy-related proteins LC3, Beclin-1, Atg5 and Atg7 were enhanced by PSG-1. These findings demonstrated that PSG-1 could ameliorate Cy-induced impairment of intestinal immunity and mucosal integrity, which maybe associated with autophagy in mice.
Asunto(s)
Autofagia/efectos de los fármacos , Enfermedades Intestinales/inducido químicamente , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Polisacáridos/farmacología , Animales , Anticuerpos , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Ciclofosfamida/efectos adversos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Ganoderma , Huésped Inmunocomprometido/efectos de los fármacos , Enfermedades Intestinales/patología , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos BALB C , Proteínas de Uniones Estrechas/metabolismoRESUMEN
The study aimed to investigate the protective effect and underlying mechanism of Ganoderma atrum (G. atrum) polysaccharide (PSG-1) on macrophage injury induced by acrolein. The results showed that PSG-1 restored the cell viability damaged by acrolein. In addition, PSG-1 significantly reduced the acrolein-induced occurrence of apoptosis via increase of Bcl-2 expression, mitochondrial membrane potential (MMP), decrease of ROS, cytochrome c (Cyt-C), caspase-3, caspase-9. Moreover, the overexpressions of autophagy-related proteins (LC3, Beclin-1, Atg7 and Atg5) were suppressed by PSG-1, which demonstrated that PSG-1 inhibited autophagy in acrolein treated macrophage. Beside, PSG-1 significantly elevated the expression level of p-mTOR, suggested that PSG-1 mediated autophagy through mTOR pathway. Furthermore, inhibitor of autophagy could inhibit apoptosis in acrolein-induced macrophage, suggesting that autophagy may be involved in the regulation of apoptosis. In summary, the present study demonstrated that PSG-1 protected acrolein-induced macrophage injury via autophagy-dependent apoptosis.
Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Ganoderma/química , Macrófagos/efectos de los fármacos , Polisacáridos/farmacología , Sustancias Protectoras/farmacología , Acroleína/efectos adversos , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Supervivencia Celular/efectos de los fármacos , Ratones , Células RAW 264.7 , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
The present study aimed to determine the cardioprotective effect of Ganoderma atrum polysaccharide (PSG-1) in doxorubicin (DOX)-treated mice and its underlying mechanism. Results indicated that PSG-1 treatment significantly alleviated DOX-induced myocardial damage via attenuating apoptosis and maintaining the structure of myocardial mitochondria. Meanwhile, PSG-1-evoked cardioprotection was associated with an increase of manganese superoxide dismutase activity and decrease of caspases activities. Moreover, administration of PSG-1 suppressed DOX-induced mitochondrial disorders, which was evidenced by reducing reactive oxygen species, elevating mitochondrial membrane potential and inhibiting the opening of mitochondrial permeability transition pore. PSG-1 was also found to reduce the release of cytochrome c from mitochondria to cytoplasm in mice subjected to DOX. Finally, our findings have provided comprehensive evidence for the cardioprotective effects of PSG-1 via reduction of apoptosis mediated by modification of the mitochondrial intrinsic apoptotic pathway, indicating that PSG-1 could be developed as an effective therapeutic strategy to prevent DOX-induced cardiotoxicity in clinical settings.
Asunto(s)
Antibióticos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Ganoderma/química , Mitocondrias/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Polisacáridos/farmacología , Animales , Antibióticos Antineoplásicos/química , Doxorrubicina/química , Ratones , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Polisacáridos/química , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Our previous study has demonstrated that Ganoderma atrum polysaccharide (PSG-1) has immunomodulatory activity on spleen lymphocytes. However, how PSG-1 exerts its effect on purified lymphocytes is still obscure. Thus, this study aimed to investigate the immunomodulatory activity of PSG-1 on purified T lymphocytes and further elucidate the underlying mechanism based on RNA sequencing (RNA-seq). Our results showed that PSG-1 promoted T lymphocytes proliferation and increased the production of IL-2, IFN-γ, and IL-12. Meanwhile, RNA-seq analysis found 394 differentially expressed genes. KEGG pathway analysis identified 20 significant canonical pathways and seven biological functions. Furthermore, PSG-1 elevated intracellular Ca2+ concentration and calcineurin (CaN) activity and raised the p-ERK, p-JNK, and p-p38 expression levels. T lymphocytes proliferation and the production of IL-2, IFN-γ, and IL-12 were decreased by the inhibitors of calcium channel and mitogen-activated protein kinases (MAPKs). These results indicated that PSG-1 possesses immunomodulatory activity on purified T lymphocytes, in which Ca2+/CaN and MAPK pathways play essential roles.
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Calcineurina/inmunología , Calcio/inmunología , Ganoderma/química , Factores Inmunológicos/farmacología , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Linfocitos T/efectos de los fármacos , Verduras/química , Calcineurina/genética , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Interleucina-12/genética , Interleucina-12/inmunología , Interleucina-2/genética , Interleucina-2/inmunología , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/inmunología , Análisis de Secuencia de ARN , Linfocitos T/inmunología , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/inmunologíaRESUMEN
Ganoderma atrum (G. atrum), a member of the genus Ganoderma, is an edible and medicinal fungus. In this study, we investigated the direct and indirect effects of G. atrum polysaccharide (PSG-1) on dendritic cells (DCs). Firstly, flow cytometric and ELISA analysis showed that PSG-1 increased cell surface molecule expression of MHC-II, CD80 and CD86, and enhanced the production of IL-12 p70, IL-6, IL-10, RANTES, MIP-1α and MCP-1 in DCs. PSG-1-treated DCs promoted the proliferation of splenic T lymphocyte of mouse in mixed lymphocyte reaction. The above results demonstrated that PSG-1 induced the maturation of DCs. Secondly, PSG-1 increased the phosphorylation of p38, ERK and JNK determined by western blot. Inhibitors of p38, ERK and JNK decreased PSG-1-induced expression of MHC-II, CD80 and CD86 and production of IL-6 and IL-10 by DCs. These results suggested that PSG-1 induced mitogen-activated protein kinase (MAPK) activation was involved in the regulation of maturation markers and cytokines expression in DCs. Finally, PSG-1 increased expression of MHC-II of DCs in a DCs-Caco-2 co-culture model, suggesting that PSG-1 could indirectly influence DCs. In summary, our data suggested that PSG-1 directly induced DCs maturation via activating MAPK pathways, and indirectly stimulated DCs separated by intestinal epithelial cells.
Asunto(s)
Células Dendríticas/efectos de los fármacos , Ganoderma/química , Polisacáridos/farmacología , Animales , Biomarcadores , Células CACO-2 , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Macrófagos/clasificación , Macrófagos/efectos de los fármacos , Macrófagos/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Polisacáridos/químicaRESUMEN
Ganoderma atrum polysaccharide (PSG-1), a main polysaccharide from Ganoderma atrum, possesses potent antioxidant capacity and cardiovascular benefits. The aim of this study was to investigate the role of PSG-1 in oxidative stress and apoptosis in human umbilical vein endothelial cells (HUVECs) under anoxia/reoxygenation (A/R) injury conditions. The results showed that exposure of HUVECs to A/R triggered cell death and apoptosis. Administration of PSG-1 significantly inhibited A/R-induced cell death and apoptosis in HUVECs. PSG-1-reduced A/R injury was mediated via mitochondrial apoptotic pathway, as evidenced by elevation of mitochondrial Bcl-2 protein and mitochondrial membrane potential, and attenuation of Bax translocation, cytochrome c release and caspases activation. Furthermore, PSG-1 enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase and glutathione content, and concomitantly attenuated reactive oxygen species generation, lipid peroxidation and glutathione disulfide content. The antioxidant, N-acetyl-l-cysteine, significantly ameliorated all of these endothelial injuries caused by A/R, suggesting that antioxidant activities might play a key role in PSG-1-induced endothelial protection. Taken together, these findings suggested that PSG-1 could be as a promising adjuvant against endothelial dysfunction through ameliorating oxidative stress and apoptosis.
Asunto(s)
Apoptosis/efectos de los fármacos , Polisacáridos Fúngicos/farmacología , Ganoderma/química , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Estrés Oxidativo/efectos de los fármacos , Oxígeno/metabolismo , Antioxidantes/metabolismo , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Citocromos c/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Peroxidación de Lípido/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Ganoderma atrum polysaccharide (PSG-1) is a bioactive compound with antioxidant and immunomodulatory activities. The aim of this study was to determine the effect of PSG-1 on reactive oxygen species (ROS) generation and apoptosis in spleen and thymus of cyclophosphamide (CTX)-induced immunosuppressed mice. The results showed that PSG-1 protected mice against CTX-mediated immunosuppression, as evidenced by enhancing the ratios of thymus and spleen weights to body weight, promoting T cell and B cell survival, and increasing levels of TNF-α and IL-2. Apoptosis, ROS generation and lipid peroxidation in the immune organs of the immunosuppressed animals were ameliorated by PSG-1. The immune benefits of PSG-1 were associated with the enhancement of the activities of glutathione peroxidase, superoxide dismutase and catalase in the immune organs, implying that antioxidant activities of PSG-1 may play an important role in PSG-1-evoked immune protection. Taken together, these findings have demonstrated that PSG-1 may ameliorate CTX-induced immunosuppression through reducing apoptosis and oxidative damage in immunological system.
Asunto(s)
Ganoderma/química , Terapia de Inmunosupresión/efectos adversos , Polisacáridos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Bazo/efectos de los fármacos , Timo/efectos de los fármacos , Animales , Antineoplásicos Alquilantes/farmacología , Antioxidantes/metabolismo , Ciclofosfamida/farmacología , Ratones , Tamaño de los Órganos/efectos de los fármacos , Bazo/metabolismo , Bazo/patología , Timo/metabolismo , Timo/patologíaRESUMEN
The aim of the present study was to examine the role of Ganoderma atrum polysaccharide (PSG-1) in reactive oxygen species (ROS) generation and mitochondrial function in hyperglycemia-induced angiopathy. In this work, ROS scavenger, oxidizing agent tert-butylhydroperoxide (tBH), mitochondrial permeability transition pore (mPTP) blockers, and caspase inhibition are used to investigate whether PSG-1 may promote survival of human umbilical vein cells (HUVECs) through preventing the overproduction of ROS and mitochondrial dysfunction. Experimental results show that exposure of HUVECs to 35.5 mmol/L glucose increases the proportion of cells undergoing apoptosis. PSG-1, mPTP blocker, or caspase inhibition can reduce apoptosis and ROS generation. PSG-1 also increases mitochondrial Bcl-2 protein formation and mitochondrial membrane potential (ΔΨm) but inhibits Bax translocation, cytochrome c release, and caspase activation. In summary, vascular protection of PSG-1 can be mediated by a mitochondria-ROS pathway. ROS generation and mPTP induction are critical for high glucose-mediated apoptosis. PSG-1 ameliorates endothelial dysfunction by inhibiting oxidative stress and subsequent mitochondrial dysfunction.
Asunto(s)
Apoptosis/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Ganoderma/química , Glucosa/farmacología , Mitocondrias/fisiología , Polisacáridos/farmacología , Apoptosis/fisiología , Inhibidores de Caspasas/farmacología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hiperglucemia/complicaciones , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Proteínas de Transporte de Membrana Mitocondrial/antagonistas & inhibidores , Poro de Transición de la Permeabilidad Mitocondrial , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Enfermedades Vasculares/etiología , Enfermedades Vasculares/prevención & control , terc-Butilhidroperóxido/farmacologíaRESUMEN
The aim of this study was to investigate the molecular mechanism underlying the immunomodulatory effect of Ganoderma atrum polysaccharide (PSG-1) in spleen lymphocytes. Our results showed that PSG-1 increased the intracellular Ca2+ concentration and calcineurin (CaN) activity. Moreover, PSG-1 was found to elevate nuclear factor of activated T cells (NFAT) activity, but this effect could be diminished by the treatment of CaN inhibitors (cyclosporin A and FK506). PSG-1-induced interleukin (IL)-2 production was also inhibited by cyclosporin A and FK506. In addition, PSG-1 was found to significantly enhance protein kinase C (PKC) activity. PKC was involved in induction of NFAT activity by PSG-1, as evidenced by abrogation of NFAT activity by PKC inhibitor calphostin C, which significantly decreased PSG-1-induced IL-2 production. On the basis of these results, we concluded that PSG-1 may induce activation of spleen lymphocytes at least in part via the Ca2+/CaN/NFAT/IL-2 signaling pathway and the PKC/NFAT/IL-2 signaling pathway cooperatively regulated PSG-1-induced activation of spleen lymphocytes.
Asunto(s)
Ganoderma/química , Factores Inmunológicos/farmacología , Linfocitos/efectos de los fármacos , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Bazo/efectos de los fármacos , Verduras/química , Animales , Células Cultivadas , Femenino , Interleucina-2/inmunología , Activación de Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Ratones , Ratones Endogámicos BALB C , Transducción de Señal/efectos de los fármacos , Bazo/citología , Bazo/inmunologíaRESUMEN
The aim of this study is to investigate the role of Toll-like receptor (TLR) 4 in Ganoderma atrum polysaccharide (PSG-1)-induced antitumor activity. In vitro, the apoptosis rate of S-180 cells was increased in PSG-1-induced peritoneal macrophage derived from C3H/HeN (wild-type) mice, but not from C3H/HeJ (TLR4-deficient) mice. In the S-180 tumor model, phagocytosis, NO and ROS release, phosphorylation of MAPKs and Akt, and expression of NF-κB were increased by PSG-1 in peritoneal macrophage derived from C3H/HeN mice. Furthermore, PSG-1 elevated Th1 cytokine production and enhanced the cytotoxic activity of CTL and NK cells in C3H/HeN mice. In addition, PSG-1 decreased the tumor weight and increased the apoptosis rate and caspase-3 and caspase-9 activities of tumor derived from the C3H/HeN mice. However, none of these activities were observed in C3H/HeJ mice. In summary, these findings demonstrated that the antitumor activity of PSG-1 is mediated by TLR4.
Asunto(s)
Antineoplásicos/administración & dosificación , Ganoderma/química , Neoplasias/tratamiento farmacológico , Polisacáridos/administración & dosificación , Receptor Toll-Like 4/inmunología , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Femenino , Humanos , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Ratones , Ratones Endogámicos C3H , Ratones Noqueados , Neoplasias/genética , Neoplasias/inmunología , Neoplasias/fisiopatología , Fagocitosis/efectos de los fármacos , Células TH1/efectos de los fármacos , Células TH1/inmunología , Receptor Toll-Like 4/genéticaRESUMEN
Ganoderma atrum is one species of edible and pharmaceutical mushroom with various biological activities. Recently, a novel polysaccharide, PSG-1, was purified from G. atrum. The antitumor activity and its mechanism of action were studied. In vitro, PSG-1 has little effect on inhibiting proliferation of CT26 tumor cells. However, the tumor size was significantly decreased in PSG-1-treated mice. The results showed that PSG-1 induced apoptosis in CT26 cells. Moreover, the intracellular cyclic AMP (cAMP) level and protein kinase A (PKA) activity were markedly increased in PSG-1-treated mice. In contrast, the contents of cyclic GMP and DAG and the PKC activity were decreased. Similarly, the expression of PKA protein was upregulated, while PKC protein expression in PSG-1-treated group was lowered. Additionally, PSG-1 increased the immune organ index and serum biochemistry parameter. In general, PSG-1 enhances the antitumor immune response, induces apoptosis in CT26-bearing mice, and could be a safe and effective adjuvant for tumor therapy or functional food.
Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Medicamentos Herbarios Chinos/administración & dosificación , Ganoderma/química , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Polisacáridos/administración & dosificación , Animales , Línea Celular Tumoral , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Neoplasias/fisiopatologíaRESUMEN
Ganoderma atrum polysaccharide (PSG-1) has been commonly suggested as a candidate for prevention and therapy of cancer. We investigated the antitumor effect and the underlying molecular mechanisms of PSG-1. The results showed that PSG-1 inhibited tumor growth and resulted in tumor cell apoptosis in vivo. Here, the data revealed that PSG-1 caused a markedly increase in cAMP and PKA activities, rather than cGMP and PKC. Moreover, the treatment of PSG-1 induced a dramatic increase in the protein level of PKA. In contrast, the expression of PKC and intracellular [Ca(2+)]i were inhibited. Our study also revealed that treatment with PSG-1 increased the spleen and thymus weights, lymphocyte proliferation and macrophage phagocytic activity in tumor-bearing mice. Taken together, we conclude that PSG-1 could inhibit the tumor growth, possibly in part by enhancing the induction of apoptosis through cAMP-PKA signaling pathway and down-regulation of Ca(2+)/PKC signal pathway, activating host immune function in S180-bearing mice.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Ganoderma/química , Polisacáridos/farmacología , Proteína Quinasa C/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/genética , GMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Femenino , Macrófagos/efectos de los fármacos , Ratones , Neoplasias/tratamiento farmacológico , Proteína Quinasa C/genética , Bazo/citología , Bazo/efectos de los fármacosRESUMEN
A newly identified polysaccharide (PSG-1) has been purified from Ganoderma atrum. The study was to investigate the protective effect of PSG-1 on diabetes-induced endothelial dysfunction in rat aorta. Rats were fed a high fat diet for 8 weeks and then injected with a low dose of streptozotocin to induce type 2 diabetes. The diabetic rats were orally treated with PSG-1 for 4 weeks. It was found that administration of PSG-1 significantly reduced levels of fasting blood glucose, improved endothelium-dependent aortic relaxation, increased levels of phosphoinositide 3-kinase (PI3K), phospho-Akt (p-Akt), endothelial nitric oxide synthase (eNOS) and nitric oxide in the aorta from diabetic rats, compared to un-treated diabetics. These results suggested that the protective effects of PSG-1 against endothelial dysfunction may be related to activation of the PI3K/Akt/eNOS pathway.
Asunto(s)
Aorta/efectos de los fármacos , Diabetes Mellitus Experimental/tratamiento farmacológico , Ganoderma/química , Proteína Oncogénica v-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Polisacáridos/farmacología , Animales , Aorta/metabolismo , Diabetes Mellitus Experimental/metabolismo , Masculino , Óxido Nítrico Sintasa de Tipo III/metabolismo , Polisacáridos/administración & dosificación , Polisacáridos/aislamiento & purificación , Ratas , Ratas WistarRESUMEN
Ganoderma atrum has been used as Chinese traditional medicine and healthful mushroom for thousands of years. The polysaccharide is regarded as the major bioactive substances in G. atrum. To delineate the underlying mechanism and signaling cascade involved in the immunomodulatory property of G. atrum polysaccharide (PSG-1). Specifically, this study is designed to examine the possibility of TLR4 as a candidate receptor interacted with G. atrum polysaccharide (PSG-1) and elucidate the role of reactive oxygen species (ROS) in PSG-1-induced tumor necrosis factor-α (TNF-α) production during macrophage activation. Flow cytometric and confocal laser-scanning microscopy analysis showed that fluorescence-labeled PSG-1 bind specifically to the macrophages. Moreover, PSG-1 stimulated TNF-α secretion of peritoneal macrophages from C3H/HeN mice, but not from C3H/HeJ mice. PSG-1-indcued TNF-α production was suppressed by anti-TLR4 mAb. Furthermore, ROS production was mediated by TLR4, and NADPH oxidase-derived ROS act as upstream of phosphoinositide 3-kinase(PI3K)/Akt/mitogen-activated protein kinases(MAPKs)/nuclear factor(NF)-κB signaling pathway in the regulation of PSG-1 stimulated TNF-α production. Taken together, we conclude that PSG-1 induces TNF-α secretion through TLR4/ROS/PI3K/Akt/MAPKs/NF-κB pathways during macrophage activation. Our findings provide a molecular basis for the potential of PSG-1 as a novel immunomodulatory agent.
Asunto(s)
Activación de Macrófagos , Macrófagos/efectos de los fármacos , Polisacáridos/farmacología , Especies Reactivas de Oxígeno/metabolismo , Receptor Toll-Like 4/fisiología , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Línea Celular , Femenino , Ganoderma , Macrófagos/enzimología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C3H , FN-kappa B/metabolismo , Proteínas Quinasas/metabolismo , Transducción de SeñalRESUMEN
In this study, the chemoprotective effects of Ganoderma atrum polysaccharide (PSG-1) in cyclophosphamide (Cy) treated mice were investigated. In Cy-treated mice, PSG-1 treatment accelerated recovery dose-dependently of peripheral red blood cells, white blood cells and platelets, enhanced splenic natural killer cell activity and cytotoxic T lymphocyte activity. In addition, PSG-1 elevated CD4(+) T lymphocyte counts as well as the CD4(+)/CD8(+) ratio dose-dependently. Furthermore, PSG-1 restored the levels of IL-2, INF-γ, IL-10, IgA, IgM and IgG, as well as hemolysin in the sera. Finally, PSG-1 can also significantly increase the total antioxidant capacity, activities of superoxidase dismutase, catalase and glutathione peroxidase, and decrease the malondialdehyde level in vivo. These findings indicate that PSG-1 plays an important role in the protection against myelosuppression and immunosuppression and oxidative stress in Cy-treated mice and could be a potential immunomodulatory agent.