RESUMEN
Rheumatoid arthritis (RA) is a chronic autoimmune disease accompanied by local and systemic bone loss. FcγRs, especially FcγRIIa (hFcγRIIa), have been implicated in the pathogenesis of RA. However, the contribution of hFcγRIIa to bone loss has not been fully elucidated. In the present study, we demonstrated the double-edged sword role of hFcγRIIa on osteoclast differentiation through investigations involving hFcγRIIa-transgenic (hFcγRIIa-Tg) mice. Our findings reveal that hFcγRIIa-Tg mice, previously shown to exhibit heightened susceptibility to collagen-induced arthritis (CIA), displayed increased osteoporosis during CIA or at advanced ages (40 weeks), accompanied by heightened in vivo osteoclast differentiation. Notably, bone marrow cells from hFcγRIIa-Tg mice exhibited enhanced efficiency in differentiating into osteoclasts and bone resorption in vitro compared to wild-type mice when stimulated with receptor activators of NF-κB ligand (RANKL). Additionally, hFcγRIIa-Tg mice exhibited augmented sensitivity to RANKL-induced bone loss in vivo, highlighting the osteoclast-promoting role of hFcγRIIa. Mechanistically, bone marrow cells from hFcγRIIa-Tg mice displayed heightened Syk self-activation, leading to mTOR-pS6 pathway activation, thereby promoting RANKL-driven osteoclast differentiation. Intriguingly, while hFcγRIIa crosslinking hindered RANKL-induced osteoclast differentiation, it activated the kinase cAbl, subsequently triggering STAT5 activation and inhibiting the expression of osteoclast-associated genes. This study provides novel insights into hFcγRIIa-mediated osteoclast biology, suggesting promising therapeutic targets for managing bone remodeling disorders.
Asunto(s)
Resorción Ósea , Diferenciación Celular , Ratones Transgénicos , Osteoclastos , Osteogénesis , Receptores de IgG , Animales , Receptores de IgG/genética , Receptores de IgG/metabolismo , Ratones , Osteoclastos/metabolismo , Osteogénesis/genética , Resorción Ósea/genética , Resorción Ósea/metabolismo , Ligando RANK/metabolismo , Ligando RANK/genética , Artritis Experimental/inmunología , Artritis Experimental/genética , Transducción de Señal , Artritis Reumatoide/metabolismo , Artritis Reumatoide/inmunología , Artritis Reumatoide/genética , Osteoporosis/genética , Osteoporosis/etiología , Osteoporosis/metabolismoRESUMEN
BACKGROUND: Loss-of-function mutations of ZBTB24 cause immunodeficiency, centromeric instability, and facial anomalies syndrome 2 (ICF2). ICF2 is a rare autosomal recessive disorder with immunological defects in serum antibodies and circulating memory B cells, resulting in recurrent and sometimes fatal respiratory and gastrointestinal infections. The genotype-phenotype correlation in patients with ICF2 indicates an essential role of ZBTB24 in the terminal differentiation of B cells. METHODS: We used the clustered regularly interspaced short palindromic repeats (CRISPER)/Cas9 technology to generate B cell specific Zbtb24-deficient mice and verified the deletion specificity and efficiency by quantitative polymerase chain reaction (Q-PCR) and western blotting analyses in fluorescence-activated cell sorting (FACS)-sorted cells. The development, phenotype of B cells and in vivo responses to T cell dependent or independent antigens post immunization were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Adoptive transfer experiment in combination with in vitro cultures of FACS-purified B cells and RNA-Seq analysis were utilized to specifically determine the impact of Zbtb24 on B cell biology as well as the underlying mechanisms. RESULTS: Zbtb24 is dispensable for B cell development and maintenance in naive mice. Surprisingly, B cell specific deletion of Zbtb24 does not evidently compromise germinal center reactions and the resulting primary and secondary antibody responses induced by T cell dependent antigens (TD-Ags), but significantly inhibits T cell independent antigen-elicited antibody productions in vivo. At the cellular level, Zbtb24-deficiency specifically impedes the plasma cell differentiation of B1 cells without impairing their survival, activation and proliferation in vitro. Mechanistically, Zbtb24-ablation attenuates heme biosynthesis partially through mTORC1 in B1 cells, and addition of exogenous hemin abrogates the differentiation defects of Zbtb24-null B1 cells. CONCLUSIONS: Zbtb24 seems to regulate antibody responses against TD-Ags B cell extrinsically, but it specifically promotes the plasma cell differentiation of B1 cells via heme synthesis in mice. Our study also suggests that defected B1 functions contribute to recurrent infections in patients with ICF2.
Asunto(s)
Diferenciación Celular , Enfermedades de Inmunodeficiencia Primaria , Animales , Ratones , Enfermedades de Inmunodeficiencia Primaria/genética , Linfocitos B/inmunología , Linfocitos B/metabolismo , Ratones Endogámicos C57BL , Síndromes de Inmunodeficiencia/genética , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Ratones Noqueados , Cara/anomalíasRESUMEN
Calreticulin (CRT) is a major calcium-binding luminal resident protein on the endoplasmic reticulum that can also be released extracellular as well as anchored on surface of cells. Previously, we demonstrated that soluble recombinant CRT fragment 39-272 (CRT/39-272) exhibited potent immunostimulatory effects as well as immunoregulation effects on immune cells. Here, we constructed stable B16 melanoma cell lines expressing recombinant CRT/39-272 on the membrane (B16-tmCRT/39-272) to investigate the roles of cell surface CRT on tumor progression. We found that B16-tmCRT/39-272 cells subcutaneously inoculated into C57BL/6 mice exhibited stronger tumorigenicity than the B16-EGFP control cells. The tumor associated macrophages infiltrated in tumors were mainly M2 phenotype. Regulatory T cells (Tregs) were also expanded more in bearing mice. Consistent with the in vivo results, B16-tmCRT/39-272 promoted macrophage polarization toward F4/80+CD206+ M2 macrophages and promoted transforming growth factor beta (TGF-ß) secretion in vitro, which could promote naïve CD4+ T cell differentiation into Tregs. These results imply that the tmCRT/39-272 could accelerate tumor development by enhancing M2 macrophage polarization to induce TGF-ß secretion, and then promoted Treg differentiation in the tumor microenvironment. Our data may provide useful clues for better understanding of the potentiating roles of CRT in tumorigenesis.
Asunto(s)
Calreticulina , Melanoma Experimental , Animales , Calcio/metabolismo , Calreticulina/genética , Calreticulina/metabolismo , Línea Celular Tumoral , Ratones , Ratones Endogámicos C57BL , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Microambiente TumoralRESUMEN
Given the importance of B lymphocytes in inflammation and immune defense against pathogens, mice transgenic for Cre under the control of Cd19 promoter (Cd19Cre/+ mice) have been widely used to specifically investigate the role of loxP-flanked genes in B cell development/function. However, impacts of expression/insertion of the Cre transgene on the phenotype and function of B cells have not been carefully studied. Here, we show that the number of marginal zone B and B1a cells was selectively reduced in Cd19Cre/+ mice, while B cell development in the bone marrow and total numbers of peripheral B cells were comparable between Cd19Cre/+ and wild type C57BL/6 mice. Notably, humoral responses to both T cell-dependent and independent antigens were significantly increased in Cd19Cre/+ mice. We speculate that these differences are mainly attributable to reduced surface CD19 levels caused by integration of the Cre-expressing cassette that inactivates one Cd19 allele. Moreover, our literature survey showed that expression of Cd19Cre/+ alone may affect the development/progression of inflammatory and anti-infectious responses. Thus, our results have important implications for the design and interpretation of results on gene functions specifically targeted in B cells in the Cd19Cre/+ mouse strain, for instance, in the context of (auto) inflammatory/infectious diseases.
Asunto(s)
Antígenos CD19 , Linfocitos B , Animales , Anticuerpos/metabolismo , Antígenos CD19/metabolismo , Integrasas , Ratones , Ratones Endogámicos C57BL , FenotipoRESUMEN
28-O-caffeoyl betulin (B-CA) has been demonstrated to reduce the cerebral infarct volume caused by transient middle cerebral artery occlusion (MCAO) injury. B-CA is a novel derivative of naturally occurring caffeoyl triterpene with little information associated with its pharmacological target(s). To date no data is available regarding the effect of B-CA on brain metabolism. In the present study, a 1H-NMR-based metabolomics approach was applied to investigate the therapeutic effects of B-CA on brain metabolism following MCAO in rats. Global metabolic profiles of the cortex in acute period (9 h after focal ischemia onset) after MCAO were compared between the groups (sham; MCAO + vehicle; MCAO + B-CA). MCAO induced several changes in the ipsilateral cortex of ischemic rats, which consequently led to the neuronal damage featured with the downregulation of NAA, including energy metabolism dysfunctions, oxidative stress, and neurotransmitter metabolism. Treatment with B-CA showed statistically significant rescue effects on the ischemic cortex of MCAO rats. Specifically, treatment with B-CA ameliorated the energy metabolism dysfunctions (back-regulating the levels of succinate, lactate, BCAAs, and carnitine), oxidative stress (upregulating the level of glutathione), and neurotransmitter metabolism disturbances (back-regulating the levels of γ-aminobutyric acid and acetylcholine) associated with the progression of ischemic stroke. With the administration of B-CA, the levels of three phospholipid related metabolites (O-phosphocholine, O-phosphoethanolamine, sn-glycero-3-phosphocholine) and NAA improved significantly. Overall, our findings suggest that treatment with B-CA may provide neuroprotection by augmenting the metabolic changes observed in the cortex following MCAO in rats.
Asunto(s)
Corteza Cerebral/metabolismo , Infarto de la Arteria Cerebral Media/metabolismo , Enfermedades Metabólicas/metabolismo , Metaboloma/efectos de los fármacos , Fármacos Neuroprotectores/uso terapéutico , Triterpenos/uso terapéutico , Animales , Corteza Cerebral/efectos de los fármacos , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Masculino , Enfermedades Metabólicas/tratamiento farmacológico , Metabolómica , Espectroscopía de Protones por Resonancia Magnética , Curva ROC , Ratas Sprague-DawleyRESUMEN
BACKGROUND: Infection is common in acute-on-chronic liver failure (ACLF), which may worsen the clinical condition and prognosis. However, the characteristics of infection and its influence on prognosis in hepatitis B virus related ACLF (HBV-ACLF) as defined by the European Association for the Study of the Liver (EASL) have not been clarified. We aimed to investigate the characteristics of infection and its influence on mortality in patients with HBV-ACLF defined by EASL in China. METHODS: We performed a retrospective cohort study in patients with HBV-ACLF defined by EASL in a single center from January 2015 to December 2017. These patients were divided into two groups with and without infection. The incidence, sites of infection, isolated strains, and risk factors associated with mortality were evaluated. RESULTS: A total of 289 patients were included, among them 185 (64.0%) were diagnosed with an infection. The most common type of infection was pneumonia (55.7%), followed by spontaneous bacterial peritonitis (47.6%) and others. The gram-negative bacteria were the most frequent (58.3%). Patients with one, two, and three or more infection sites had a gradually increasing incidence of sepsis (P < 0.01), septic shock (P < 0.001), and ACLF-3 (P < 0.05). Also, patients with infection isolated one, two, and three or more strains showed a growing incidence of sepsis (P < 0.01) and septic shock (P < 0.001). Patients with infection showed a significantly higher 28-day mortality than those without (P < 0.01), especially in patients with ACLF-3. Infection was identified as an independent risk factor for 28-day mortality in all HBV-ACLF patients. Pneumonia and sepsis were identified as independent predictors of 28-day mortality for patients with infection. CONCLUSIONS: Infection is associated with severe clinical course and high mortality in HBV-ACLF defined by EASL. The increased number of infection sites or isolated strains was associated with the occurrence of sepsis and septic shock. Pneumonia and sepsis were independent predictors for mortality in HBV-ACLF patients with infection.
Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Hepatitis B , Insuficiencia Hepática Crónica Agudizada/epidemiología , China/epidemiología , Hepatitis B/complicaciones , Hepatitis B/epidemiología , Virus de la Hepatitis B , Humanos , Pronóstico , Estudios RetrospectivosRESUMEN
Host-plant volatiles play vital roles for insects to locate foraging, mating, and oviposition sites in the environment. As one of the devastating invasive forestry pests, Hyphantria cunea causes a great annual loss in China, and understanding its chemical ecology is an important task. The current research was done in terms of chemical analysis, electrophysiology, and behavioral assays on H. cunea to assess its olfactory reception toward host-plant volatiles. A screen of possible common host volatiles was done, targeting on five favored hosts of H. cunea, harvesting six potential bioactive compounds from a total of 78 odorant components. Six types of antennal sensilla were investigated on their distributions on the antennae, and sexual dimorphism was described. H. cunea showed responses to all selected host-related volatiles in electroantennogram tests, and linalyl butyrate elicited the strongest responses. Furthermore, mating rates in adult pairs that are exposed to dibutyl phthalate and phytol have been significantly increased, while oviposition rates and female fecundity were not influenced. The results of the current study provide initial evidence showing that universal host-derived volatile cues are essential for H. cunea moth in terms of mating, which can also provide insights into the development of botanical attractants.
RESUMEN
CD100 is an immune semaphorin constitutively expressed on T-cells. Matrix metalloproteinase (MMP) is an important mediator of membrane-bound CD100 (mCD100) cleavage to generate soluble CD100 (sCD100), which has immunoregulatory activity in immune cell responses. The aim of the study was to investigate the level and role of sCD100 and mCD100 in modulating CD8+ T-cell function in non-small cell lung cancer (NSCLC). sCD100 and MMP-14 levels in the serum and bronchoalveolar lavage fluid (BALF), and mCD100 expression on peripheral and lung-resident CD8+ T-cells were analysed in NSCLC patients. The ability to induce sCD100 and the effect of MMP-14 on mCD100 shedding for the regulation of non-cytolytic and cytolytic functions of CD8+ T-cells were also analysed in direct and indirect contact co-culture systems. NSCLC patients had lower serum sCD100 and higher mCD100 levels on CD8+ T-cells compared with healthy controls. BALF from the tumour site also had decreased sCD100 and increased mCD100 on CD8+ T-cells compared with the non-tumour site. Recombinant CD100 stimulation enhanced non-cytolytic and cytolytic functions of CD8+ T-cells from NSCLC patients, whereas blockade of CD100 receptor CD72 attenuated CD8+ T-cell activity. NSCLC patients had lower MMP-14 in the serum and in BALF from the tumour site. Recombinant MMP-14 mediated mCD100 shedding from CD8+ T-cell membrane, and led to promotion of CD8+ T-cell response in NSCLC patients. Overall, decreased MMP-14 resulted in insufficient CD100 shedding, leading to suppression of peripheral and lung-resident CD8+ T-cell activity in NSCLC.
Asunto(s)
Antígenos CD/metabolismo , Linfocitos T CD8-positivos/inmunología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Neoplasias Pulmonares/inmunología , Metaloproteinasa 14 de la Matriz/metabolismo , Semaforinas/metabolismo , Adulto , Anciano , Antígenos CD/sangre , Líquido del Lavado Bronquioalveolar/química , Linfocitos T CD8-positivos/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Membrana Celular/metabolismo , Técnicas de Cocultivo , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/patología , Activación de Linfocitos , Masculino , Metaloproteinasa 14 de la Matriz/sangre , Persona de Mediana Edad , Cultivo Primario de Células , Proteínas Recombinantes/metabolismo , Semaforinas/sangre , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Escape del Tumor , Microambiente Tumoral/inmunologíaRESUMEN
Lactoferrin (LF) is a soluble glycoprotein of the transferring family found in most biological fluids, functioning as a major first line defense molecule against infection in mammals. It also shows certain anti-tumor activity, but its clinical application in tumor therapy is limited because high dosage is required. In this study, we demonstrate that M860, a monoclonal antibody against human LF (hLF), could significantly increase the anti-tumor potential of low dosage hLF by forming LF-containing immune complex (IC). Human monocytes primed with LF-IC, but not hLF or M860 alone, or control ICs, showed strong tumoricidal activity on leukemia cell lines Jurkat and Raji through induction of secreted Granzyme B (GzB). LF-IC is able to colligate membrane-bound CD14 (a TLR4 co-receptor) and FcγRIIa (a low affinity activating Fcγ receptor) on the surface of human monocytes, thereby triggering the Syk-PI3K-AKT-mTOR pathway leading to GzB production. Our work identifies a novel pathway for LF-mediated tumoricidal activity and may extend the clinical application of LF in tumor therapy.
Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Granzimas/biosíntesis , Lactoferrina/antagonistas & inhibidores , Biomarcadores , Sinergismo Farmacológico , Expresión Génica , Granzimas/genética , Humanos , Lactoferrina/administración & dosificación , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinasa Syk/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
BACKGROUND/AIMS: Interleukin (IL)-35 has immunosuppressive functions in autoimmune diseases, infectious diseases, and certain cancers. However, few studies have focused on its immunoregulatory activity in non-small cell lung cancer (NSCLC). Thus, we investigated the role of IL-35 in the pathogenesis of this disease. METHODS: A total of 66 NSCLC patients and 21 healthy individuals were enrolled. IL-35 expression in peripheral blood and bronchoalveolar lavage fluid (BALF) was measured. The modulatory functions of IL-35 on purified CD4+ and CD8+ T cells from NSCLC patients were investigated in direct and indirect coculture systems with NSCLC cell lines. RESULTS: IL-35 expression was significantly increased in BALF from the tumor site, but not in the peripheral blood of NSCLC patients. IL-35 did not affect the bioactivity including proliferation, cytokine production, cell cycle, and cellular invasion of NSCLC cells. It suppressed responses from type 1 T helper (Th1) and Th17 cells but elevated the regulatory T cell response in cultured CD4+ T cells from NSCLC patients, and reduced cytokine-mediated CD4+ T cells cytotoxicity to NSCLC cells. Moreover, IL-35 also inhibited cytotoxic gene expression in CD8+ T cells from NSCLC, reducing their cytolytic and noncytolytic functions. CONCLUSION: The results of this study suggest that IL-35 contributes to the dysfunction/exhaustion of T cells and limited antitumor immune responses in NSCLC.
Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Regulación Neoplásica de la Expresión Génica/inmunología , Interleucinas/inmunología , Neoplasias Pulmonares/inmunología , Proteínas de Neoplasias/inmunología , Anciano , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana EdadRESUMEN
To clarify the effects of protease inhibitors on the activities of midgut proteases in Callosobruchus chinensis (L.) larvae, the inhibitory effects of four kinds of protease inhibitors on the activities of midgut proteases of C. chinensis larvae were examined in vitro and in feeding conditions with indoor artificial insect inoculation. The activities of total protease, trypsin-like enzyme and chymotrypsin-like enzyme in the midgut of C. chinensis larvae fed on artificial mung bean that contained different contents of mung bean types in inhibitor (MBTI) were examined. The results showed that those four protease inhibitors had significant inhibitory effects on the activities of total protease, trypsin-like enzyme and chymotrypsin-like enzyme in C. chinensis larvae. The inhibitory effect was more significant when the concentration was higher. Among those inhibitors, the inhibitory effect of 20 µg·mL-1 MBTI on three kinds of enzyme activities was the strongest, with reduction of 62.5%, 41.2% and 38.7%, respectively. Ovomucoid inhibitor (OI) had the lowest inhibitory effect. The activities of three enzymes in the midgut were also inhibited by C. chinensis larvae fed with artificial mung bean containing different inhibitors. The activities of three enzymes increased with the prolongation of the instar after feeding, but they were significantly lower than that in control. The inhibitory effect of MBTI was the strongest. The inhibitory effect on the activities of total protease and trypsin-like enzyme was gradually enhanced with the increases of MBTI contents when C. chinensis larvae were fed with artificial mung bean with different contents MBTI. The inhibitory effect on chymotrypsin-like enzyme activity was not significant. When the content of MBTI was up to 20%, the activity of chymotrypsin-like enzyme was obviously inhibited.
Asunto(s)
Escarabajos/enzimología , Sistema Digestivo/enzimología , Péptido Hidrolasas/metabolismo , Animales , Larva , Inhibidores de Proteasas , TripsinaRESUMEN
The discovery of efficacious anti-ischemic drugs remains a challenge. Recently we have found that rosmarinic acid n-butyl ester (RABE), a derivative of rosmarinic acid, significantly protects SH-SY5Y cells against oxygen glucose deprivation (OGD)-induced cell death. In the present study we simultaneously investigated the effects of RABE on the two key players in the pathophysiology of cerebral ischemia, ischemic neuronal damage and microglial inflammation. Pretreatment with RABE (1, 10 µmol/L) dose-dependently attenuated OGD- or H2O2-induced reduction of the viability of SH-SY5Y neuroblastoma cells. RABE pretreatment concurrently reduced the apoptotic cell rate, down-regulated the expression of the pro-apoptotic proteins Bax and p53, and up-regulated the expression of the anti-apoptotic protein phosphorylated death-associated protein kinase (DAPK). Furthermore, pretreatment with RABE (3 µmol/L) markedly inhibited lipopolysaccharide (LPS)-induced increases in the release of TNF-α, IL-1ß, NO and PGE2, and the expression levels of iNOS, and COX-2 in cultured rat microglial cells. In conclusion, these results reveal for the first time the potential anti-ischemic effects of RABE on neuronal and glial cells and elucidate the molecular mechanisms involved in its dual beneficial profiles in vitro. RABE may be a promising drug lead/candidate for the treatment of ischemic stroke.
Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Cinamatos/farmacología , Proteínas Quinasas Asociadas a Muerte Celular/metabolismo , Depsidos/farmacología , Microglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Animales , Apoptosis/efectos de los fármacos , Hipoxia de la Célula , Línea Celular , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Glucosa/deficiencia , Humanos , Peróxido de Hidrógeno/farmacología , Lipopolisacáridos/farmacología , Microglía/metabolismo , Neuronas/patología , Óxido Nítrico/biosíntesis , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ratas Sprague-Dawley , Transducción de SeñalRESUMEN
Three new triterpenoids, celastrusins A-C (1-3), together with 3-O-caffeoyl-α-amyrin (4) were isolated from the root bark of Celastrus orbiculatus. Their structures were identified by spectroscopic analysis, X-ray crystallography using Cu Kα radiation, and the comparison of both observed and reported spectroscopic data. An in vitro bioassay revealed that the caffeoyl triterpenoid esters 1, 3, and 4 possess neuroprotective effects against oxygen-glucose deprivation (OGD) induced SH-SY5Y cell damage. Further animal studies indicated that compound 1 significantly reduced brain infarction after transient middle cerebral artery occlusion (MCAO) in rats using a 10 mg/kg (i.v.) dose.
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Ácidos Cafeicos/aislamiento & purificación , Ácidos Cafeicos/farmacología , Celastrus/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Isquemia/tratamiento farmacológico , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Fármacos Neuroprotectores/farmacología , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Animales , Ácidos Cafeicos/química , Enfermedades Arteriales Cerebrales/tratamiento farmacológico , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/química , Ésteres , Humanos , Masculino , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Ácido Oleanólico/análogos & derivados , Corteza de la Planta/química , Raíces de Plantas/química , Ratas , Triterpenos/químicaRESUMEN
The removal of excess cellular cholesterol is critical for maintaining cellular cholesterol homeostasis. Phellinus linteus polysaccharide extracts (PLPEs) is an immunomudulatory agent with a molecular weight of 153 kd. Here, we analyzed the effects of PLPEs on cholesterol efflux in oxidized low-density lipoprotein (ox-LDL)-loaded THP-1 (human acute monocytic leukemia cell line) macrophages. Various concentrations of PLPEs (5, 10, 20, and 100 µg/mL) were used to treat cells. Cholesterol efflux analysis was performed to analyze the cholesterol efflux ratio in PLPE-treated cells. Semiquantitative reverse transcription-polymerase chain reaction and Western blot analysis were conducted to assess the expression of target genes. Low dose of PLPEs (5-20 µg/mL) dose dependently enhanced cholesterol efflux to apolipoprotein A-I (ApoA-I), evidenced by promoting the expression of adenosine 5'-triphosphate (ATP)-binding cassette A1, ATP-binding cassette G1, and peroxisome proliferation-activated receptor γ, key regulators for cholesterol efflux. Moreover, GW9662, a potent antagonist of peroxisome proliferation-activated receptor γ, inhibited PLPE (20 µg/mL)-promoted cholesterol efflux to ApoA-I in a dose-dependent fashion. However, high dose of PLPEs (100 µg/mL) inhibited cholesterol efflux to ApoA-I from ox-LDL-loaded THP-1 macrophages, enhanced the production of superoxide anion, decreased mitochondrial membrane potential and ATP levels, and raised nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate oxidase subunits. Thus, these results indicate that low and high doses of PLPEs exhibit opposite effects on cholesterol efflux from ox-LDL-loaded THP-1 cells.
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Colesterol/metabolismo , Lipoproteínas LDL/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Polisacáridos/farmacología , Línea Celular Tumoral , Humanos , Phellinus , Extractos VegetalesRESUMEN
OBJECTIVE: To study the protective effect of resveratrol on lens epithelial cell apoptosis in diabetic cataract rat. METHODS: A total of 84 Wistar rats were divided into 4 groups: 12 in Group A (control group), 24 in Group B (diabetic cataract group), 24 in Group C (therapeutic-dose of resveratrol group) and 24 in Group D (low-dose of resveratrol group). Rats in Group B-D were given with 60 mg/kg streptozotocin through intraperitoneal injection. Rats in Group C were given with 100 mg/kg resveratrol and rats in Group D were given with 20 mg/kg resveratrol. The caspase-3 expression levels and apoptosis ratios of LEC among each group were observed; the degrees of lens opacity in Group B-D after 12 weeks were compared. RESULTS: There were significant differences in caspase-3 expression levels, apoptosis ratios of LEC among groups at 4 w, 8 w and 12 w (P<0.05). After 12 weeks, in Group B the degree of lens opacity was as follow: 0 (0.00%) in grade I, 3 (37.50%) in grade II, 2 (25.00%)in grade III, 2 (25.00%)grade IV, and 1 (12.50%) in grade V; in Group C: 2 (25.00%)in grade I, 4 (50.00%) in grade II, 2 (25.00%)in grade III, 0 (0.00%)grade IV, and 0 (0.00 %) in grade V; in Group D: 1 (12.50%)in grade I, 4 (50.00%) in grade II, 2 (25.00%) in grade III, 1 (12.50%) grade IV, and 0 (0.00%) in grade V. The difference among Group B-D was statistically significant (P<0.05). CONCLUSIONS: Resveratrol has protective effect on lens epithelial cell apoptosis in diabetic cataract rat, and the effect is relative to its dose.
RESUMEN
Despite the intense efforts in searching for stroke therapies, an urgent need still exists to explore novel neuroprotective agents for ischemic stroke that have high efficacy and wide therapeutic time-window. Here, we provide the first demonstration that 28-O-caffeoyl betulin (B-CA), a novel derivative of naturally occurring caffeoyl triterpene, could significantly alleviate brain infarction and neurological deficit when given as late as 6 h after transient middle cerebral artery occlusion in the rat. Moreover, post-ischemia B-CA administration exhibited long-term (14 days post stroke) protective effects on both brain infarction and functional (i.e., motor and sensory) deficits. Protective B-CA effects correlated with decreased inflammatory responses as indicated by inhibition of microglia and astrocyte activation [stained with ionized calcium-binding adapter molecule 1 (Iba-1) and glial fibrillary acidic protein (GFAP) antibody, respectively], as well as suppression of tumor necrosis factor-α, interleukin-1ß, and cyclooxygenase-2 overproduction in the ipsilateral cortex of ischemic rat. B-CA administration caused significant hypothermia in the focal cerebral ischemic rat, which may contribute to its ameliorative effects on brain damage and inflammation. In view of its potency in wide therapeutic time-window, robust anti-inflammatory and hypothermic effects, this novel caffeoyl triterpene derivative may lead toward the development of effective therapeutic strategies for the treatment of ischemic stroke.
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Antiinflamatorios no Esteroideos/uso terapéutico , Isquemia Encefálica/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Triterpenos/uso terapéutico , Animales , Isquemia Encefálica/patología , Citocinas/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/patología , Ataque Isquémico Transitorio/tratamiento farmacológico , Ataque Isquémico Transitorio/patología , Masculino , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/tratamiento farmacológicoRESUMEN
Chemical investigation of the cupules of Lithocarpus polystachyus resulted in the identification of four 3,4-seco-homo-cycloartane and one homo-cycloartane derivatives named lithocarpic acids O-S. Their structures were determined based on extensive 1D/2D NMR, IR, MS spectroscopic analyses and chemical methods. Lithocarpic acid O (1) exhibited inhibitory activities on mouse and human isozymes of 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) with IC50 values of 0.49 and 1.1 µM, respectively.