ABSTRACT
Atherosclerosis (AS) is the main cause of cardiovascular diseases. This study investigated Yirui (YR) capsules, whose ingredients are available in health food stores, against AS and the underlying mechanisms. Male apolipoprotein E-deficient mice fed a high-fat diet for 10 weeks developed severe aortic lesions, but YR significantly decreased the plaque area in the total aorta and aortic root. YR affected the serum lipid profile by significantly reducing total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), and oxidative modification of LDL-C (Ox-LDL) levels. In addition, multi-cytokine analysis revealed that higher serum levels of interleukin-1 alpha (IL-1α), interleukin-1 beta (IL-1ß), interleukin-3 (IL-3), interleukin-6 (IL-6), interleukin-27 (IL-27), tumor necrosis factor alpha, interferon gamma, and regulated on activation, normal T cell expressed and secreted (RANTES), which were induced by a high-fat diet, declined with YR treatment. These results suggest that YR reduces the atherosclerotic plaque burden, thereby alleviating AS by modulating the lipid profile and inhibiting inflammation.
Subject(s)
Atherosclerosis/drug therapy , Drugs, Chinese Herbal/pharmacology , Inflammation/drug therapy , Animals , Atherosclerosis/blood , Chemokines/blood , Cholesterol/blood , Cytokines/blood , Diet, High-Fat/adverse effects , Inflammation/blood , Male , Mice , Mice, Inbred C57BL , Mice, Knockout, ApoE , Plaque, Atherosclerotic/blood , Plaque, Atherosclerotic/drug therapy , Plaque, Atherosclerotic/etiology , Triglycerides/bloodABSTRACT
Although it has been shown that some mannose-binding lectins (MBLs) exhibit significant activity against HIV infection, little is known about whether N-acetylgalactosamine (GalNAc)-binding lectins have the ability to inhibit HIV infection. Here, we demonstrate that a soybean-derived lectin (SBL) with GalNAc-binding affinity could potently suppress HIV infection of macrophages in a dose-dependent fashion. Unlike the MBLs, which block HIV only through binding to the glycosylated envelope proteins (gp120 and gp41) of the virus, SBL inhibited HIV at multiple steps of the virus infection/replication cycle. SBL could activate the beta interferon (IFN-ß)-STAT signaling pathway, resulting in the upregulation of a number of antiviral interferon-stimulated genes (ISGs) in macrophages. In addition, SBL treatment of macrophages induced the production of C-C chemokines, which bind to HIV entry coreceptor CCR5. Deglycosylation of cell surface galactosyl moieties or presaturation of GalNAc-binding capacity could compromise SBL-mediated induction of the antiviral factors. Furthermore, SBL exerted its anti-HIV activity in the low nanomolar range with no mitogenic effect on CD4+ T cells, a major advantage in the development of SBL as a potential anti-HIV agent compared with MBLs. These data indicate a necessity to further investigate SBL as an alternative and cost-effective anti-HIV natural product.IMPORTANCE Mannose-binding lectins (MBLs) can block the attachment of HIV to target cells and have been suggested as anti-HIV microbicides. However, the mitogenic effect of MBLs on CD4+ T cells limits this potential in clinical settings. Lectins with galactose (Gal)- or N-acetylgalactosamine (GalNAc)-binding specificity are another important category of carbohydrate-binding proteins (CBP). Compared to high-mannose N-linked glycans, GalNAc-type glycans present much less in HIV gp120 or gp41 glycosylation. Here, we demonstrate that GalNAc-specific soybean lectin (SBL) triggers antiviral signaling via recognition of the cell surface galactosyl group of macrophages, which results in the suppression of HIV at multiple steps. More importantly, SBL has no mitogenic effect on the activation of CD4+ T cells, a major advantage in the development of Gal/GalNAc-specific lectins as naturopathic anti-HIV agents.
Subject(s)
Anti-HIV Agents/pharmacology , HIV Infections/drug therapy , HIV-1/immunology , Macrophages/immunology , Plant Lectins/pharmacology , Soybean Proteins/pharmacology , Virus Internalization/drug effects , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/pathology , HIV Envelope Protein gp120/immunology , HIV Envelope Protein gp41/immunology , HIV Infections/immunology , HIV Infections/pathology , HIV-1/pathogenicity , Humans , Interferon-beta/immunology , Macrophages/pathology , Macrophages/virology , Receptors, CCR5/immunology , STAT Transcription Factors/immunology , Signal Transduction/drug effects , Signal Transduction/immunologyABSTRACT
AIM: To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on polyinosinic-polycytidylic acid (poly I:C)-triggered intracellular innate immunity against hepatitis C virus (HCV) in hepatocytes. METHODS: A cell culture model of HCV infection was generated by infecting a hepatoma cell line, Huh7, with HCV JFH-1 strain (JFH-1-Huh7). Poly I:C with a high molecular weight and EGCG were used to stimulate the JFH-1-Huh7 cells. Real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of intracellular mRNAs and of intracellular and extracellular HCV RNA. Enzyme-linked immunosorbent assay was used to evaluate the interferon (IFN)-λ1 protein level in the cell culture supernatant. Immunostaining was used to examine HCV core protein expression in Huh7 cells. RESULTS: Our recent study showed that HCV replication could impair poly I:C-triggered intracellular innate immune responses in hepatocytes. In the current study, we showed that EGCG treatment significantly increased the poly I:C-induced expression of Toll-like receptor 3 (TLR3), retinoic acid-inducible gene I, and IFN-λ1 in JFH-1-Huh7 cells. In addition, supplementation with EGCG increased the poly I:C-mediated antiviral activity in JFH-1-Huh7 cells at the intracellular and extracellular HCV RNA and protein levels. Further investigation of the mechanisms showed that EGCG treatment significantly enhanced the poly I:C-induced expression of IFN-regulatory factor 9 and several antiviral IFN-stimulated genes, including ISG15, ISG56, myxovirus resistance A, and 2'-5'-oligoadenylate synthetase 1, which encode the key antiviral elements in the IFN signaling pathway. CONCLUSION: Our observations provide experimental evidence that EGCG has the ability to enhance poly I:C-induced intracellular antiviral innate immunity against HCV replication in hepatocytes.
Subject(s)
Antiviral Agents/pharmacology , Catechin/analogs & derivatives , Hepacivirus/physiology , Hepatitis C/immunology , Immunity, Innate/drug effects , Interferon-gamma/immunology , Poly I-C/immunology , Antiviral Agents/therapeutic use , Catechin/pharmacology , Catechin/therapeutic use , Cell Line, Tumor , DEAD Box Protein 58/immunology , DEAD Box Protein 58/metabolism , Enzyme-Linked Immunosorbent Assay , Hepatitis C/drug therapy , Hepatitis C/virology , Hepatocytes , Humans , Interferon-Stimulated Gene Factor 3, gamma Subunit/immunology , Interferon-Stimulated Gene Factor 3, gamma Subunit/metabolism , Interferon-gamma/metabolism , RNA, Viral/isolation & purification , Receptors, Immunologic , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/immunology , Toll-Like Receptor 3/metabolism , Viral Core Proteins/metabolism , Virus Replication/drug effects , Virus Replication/immunologyABSTRACT
Lipopolysaccharide- (LPS-) mediated systemic inflammation plays a critical role in neurodegenerative diseases. The present study was conducted to evaluate the protective effects of epigallocatechin gallate (EGCG), the major component in green tea, on LPS-mediated inflammation and neurotoxicity. LPS treatment of macrophages induced expression of proinflammatory cytokines (TNF-α, IL-1ß, and IL-6). However, EGCG pretreatment of macrophages significantly inhibited LPS-mediated induction of these cytokines. In addition, EGCG significantly diminished LPS-induced inflammatory cytokines in the peripheral mononuclear blood cells (PBMCs). Supernatant from EGCG-pretreated and LPS-activated macrophage cultures was found to be less cytotoxic to neurons than that from non-EGCG-pretreated and LPS-activated macrophage cultures. Furthermore, EGCG treatment of neurons could inhibit LPS-induced production of reactive oxygen species (ROS). Thus EGCG represents a potent and useful neuroprotective agent for inflammation-mediated neurological disorders.
Subject(s)
Catechin/analogs & derivatives , Inflammation/prevention & control , Leukocytes, Mononuclear/immunology , Lipopolysaccharides/immunology , Macrophages/immunology , Neurons/physiology , Neuroprotective Agents/pharmacology , Animals , Catechin/chemistry , Catechin/pharmacology , Cell Survival , Cells, Cultured , Culture Media/chemistry , Humans , Inflammation/therapy , Inflammation Mediators/immunology , Interleukin-1beta/genetics , Interleukin-6/genetics , Leukocytes, Mononuclear/drug effects , Lipopolysaccharides/administration & dosage , Macrophage Activation , Macrophages/drug effects , Neurons/drug effects , Neurons/immunology , Neuroprotective Agents/chemistry , Rats , Reactive Oxygen Species/metabolism , Real-Time Polymerase Chain Reaction , Tea/chemistry , Tumor Necrosis Factor-alpha/geneticsABSTRACT
The in vitro cytotoxicities of the ethanol extract of Andrographis paniculata (APE) and its main diterpenoid components were evaluated in various cancer cells. APE was found to be significantly growth inhibitory to human acute myeloid leukemic HL-60 cells with an IC (50) value of 14.01 microg/mL after 24 h of treatment. Among the three main diterpenoids in A. paniculata, andrographolide exhibited the highest degree of cytotoxicity followed by deoxyandrographolide while neoandrographolide was the least effective. Laser confocal microscopy and gel electrophoresis studies revealed chromosomal DNA fragmentations suggesting the occurrence of apoptosis. An increase of G (0)/G (1) phase cells from 51.88 % to 78.69 % was noted after andrographolide treatment for 36 h. The G (0)/G (1) phase arrest and apoptosis were associated with disappearance of mitochondrial cytochrome c and increased expression of Bax but decreased expression of Bcl-2 proteins in the inhibited cells. Although the order of all these events has not been determined, it is concluded that APE and andrographolide induce cell cycle arrest and affect an intrinsic mitochondria-dependent pathway of apoptosis by regulating the expression of some pro-apoptotic markers in HL-60 cells.