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Lipopolysaccharide (LPS) stimulation of Pancreatic Ductal Adenocarcinoma (PDAC) and macrophages activates the NLRP3 inflammasome that influences the levels of pro-inflammatory cytokines in a co-culture model. Cancer Biol Ther 2023; 24:2284857. [PMID: 38018872 PMCID: PMC10783839 DOI: 10.1080/15384047.2023.2284857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 11/14/2023] [Indexed: 11/30/2023] Open
Abstract
Modified macrophages, tumor-associated macrophages (TAMs), are key contributors to the survival, growth, and metastatic behavior of pancreatic ductal adenocarcinoma (PDAC) cells. Central to the role of inflammation and TAMs lies the NLRP3 inflammasome. This study investigated the effects of LPS-stimulated inflammation on cell proliferation, levels of pro-inflammatory cytokines, and the NLRP3 inflammasome pathway in a co-culture model using PDAC cells and macrophages in the presence or absence of MCC950, a NLRP3-specific inhibitor. The effects of LPS-stimulated inflammation were tested on two PDAC cell lines (Panc 10.05 and SW 1990) co-cultured with RAW 264.7 macrophages. Cell proliferation was determined using the MTT assay. Levels of pro-inflammatory cytokines, IL-1β, and TNF-α were determined by ELISA. Western blot analyses were used to examine the expression of NLRP3 in both PDAC cells and macrophages. The co-culture and interaction between PDAC cell lines and macrophages led to pro-inflammatory microenvironment under LPS stimulation as evidenced by high levels of secreted IL-1β and TNF-α. Inhibition of the NLRP3 inflammasome by MCC950 counteracted the effects of LPS stimulation on the regulation of the NLRP3 inflammasome and pro-inflammatory cytokines in PDAC and macrophages. However, MCC950 differentially modified the viability of the metastatic vs primary PDAC cell lines. LPS stimulation increased PDAC cell viability by regulating the NLRP3 inflammasome and pro-inflammatory cytokines in the tumor microenvironment of PDAC cells/macrophages co-cultures. The specific inhibition of the NLRP inflammasome by MCC950 effectively counteracted the LPS-stimulated inflammation.
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A Preliminary Predictive Model for Proliferative Lupus Nephritis in Juvenile Systemic Lupus Erythematosus. RHEUMATO 2023; 3:86-97. [DOI: 10.3390/rheumato3010007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/19/2023]
Abstract
Proliferative lupus nephritis, which is diagnosed by renal biopsy, has significant impact on the treatment choices and long-term prognosis of juvenile SLE (jSLE). Renal biopsies are however not always possible or available, thus leading to an ongoing search for alternative biomarkers. This study aimed to develop a clinical predictive machine learning model using routine standard parameters as an alternative tool to evaluate the probability of proliferative lupus nephritis (ISN/RPS Class III or IV). Data were collected retrospectively from jSLE patients seen at Selayang Hospital from 2004 to 2021. A total of 22 variables including demographic, clinical and laboratory features were analyzed. A recursive feature elimination technique was used to identify factors to predict pediatric proliferative lupus nephritis. Various models were then used to build predictive machine learning models and assessed for sensitivity, specificity and accuracy. There were 194 jSLE patients (165 females), of which 111 had lupus nephritis (54 proliferative pattern). A combination of 11 variables consisting of gender, ethnicity, fever, nephrotic state, hypertension, urine red blood cells (RBC), C3, C4, duration of illness, serum albumin, and proteinuria demonstrated the highest accuracy of 79.4% in predicting proliferative lupus nephritis. A decision-tree model performed the best with an AROC of 69.9%, accuracy of 73.85%, sensitivity of 78.72% and specificity of 61.11%. A potential clinically useful predictive model using a combination of 11 non-invasive variables to collectively predict pediatric proliferative lupus nephritis in daily practice was developed.
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Pancreatic cancer grading in pathological images using deep learning convolutional neural networks. F1000Res 2022; 10:1057. [PMID: 37767358 PMCID: PMC10521057 DOI: 10.12688/f1000research.73161.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/08/2022] [Indexed: 09/29/2023] Open
Abstract
Background: Pancreatic cancer is one of the deadliest forms of cancer. The cancer grades define how aggressively the cancer will spread and give indication for doctors to make proper prognosis and treatment. The current method of pancreatic cancer grading, by means of manual examination of the cancerous tissue following a biopsy, is time consuming and often results in misdiagnosis and thus incorrect treatment. This paper presents an automated grading system for pancreatic cancer from pathology images developed by comparing deep learning models on two different pathological stains. Methods: A transfer-learning technique was adopted by testing the method on 14 different ImageNet pre-trained models. The models were fine-tuned to be trained with our dataset. Results: From the experiment, DenseNet models appeared to be the best at classifying the validation set with up to 95.61% accuracy in grading pancreatic cancer despite the small sample set. Conclusions: To the best of our knowledge, this is the first work in grading pancreatic cancer based on pathology images. Previous works have either focused only on detection (benign or malignant), or on radiology images (computerized tomography [CT], magnetic resonance imaging [MRI] etc.). The proposed system can be very useful to pathologists in facilitating an automated or semi-automated cancer grading system, which can address the problems found in manual grading.
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Abstract
Background: Pancreatic cancer is one of the deadliest forms of cancer. The cancer grades define how aggressively the cancer will spread and give indication for doctors to make proper prognosis and treatment. The current method of pancreatic cancer grading, by means of manual examination of the cancerous tissue following a biopsy, is time consuming and often results in misdiagnosis and thus incorrect treatment. This paper presents an automated grading system for pancreatic cancer from pathology images developed by comparing deep learning models on two different pathological stains. Methods: A transfer-learning technique was adopted by testing the method on 14 different ImageNet pre-trained models. The models were fine-tuned to be trained with our dataset. Results: From the experiment, DenseNet models appeared to be the best at classifying the validation set with up to 95.61% accuracy in grading pancreatic cancer despite the small sample set. Conclusions: To the best of our knowledge, this is the first work in grading pancreatic cancer based on pathology images. Previous works have either focused only on detection (benign or malignant), or on radiology images (computerized tomography [CT], magnetic resonance imaging [MRI] etc.). The proposed system can be very useful to pathologists in facilitating an automated or semi-automated cancer grading system, which can address the problems found in manual grading.
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Genes associated with amyloid-beta-induced inflammasome-mediated neuronal death identified using functional gene trap mutagenesis approach. Int J Biochem Cell Biol 2021; 136:106014. [PMID: 34022435 DOI: 10.1016/j.biocel.2021.106014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 02/18/2021] [Accepted: 05/11/2021] [Indexed: 01/15/2023]
Abstract
Alzheimer's disease is an irreversible neurodegenerative disease, which accounts for most dementia cases. Neuroinflammation is increasingly recognised for its roles in Alzheimer's disease pathogenesis which, in part, links amyloid-beta to neuronal death. Neuroinflammatory signalling can be exhibited by neurons themselves, potentially leading to widespread neuronal cell death, although neuroinflammation is commonly associated with glial cells. The presence of the inflammasomes such as nucleotide-binding leucine-rich repeat receptors protein 1 in neurons accelerates amyloid-beta -induced neuroinflammation and has been shown to trigger neuronal pyroptosis in murine Alzheimer's disease models. However, the pathways involved in amyloid-beta activation of inflammasomes have yet to be elucidated. In this study, a gene trap mutagenesis approach was utilised to resolve the genes functionally involved in inflammasome signalling within neurons, and the mechanism behind amyloid-beta-induced neuronal death. The results indicate that amyloid-beta significantly accelerated neuroinflammatory cell death in the presence of a primed inflammasome (the NLR family pyrin domain-containing 1). The mutagenesis screen discovered the atypical mitochondrial Ras homolog family member T1 as a significant contributor to amyloid-beta-induced inflammasome -mediated neuronal death. The mutagenesis screen also identified two genes involved in transforming growth factor beta signalling, namely Transforming Growth Factor Beta Receptor 1 and SNW domain containing 1. Additionally, a gene associated with cytoskeletal reorganisation, SLIT-ROBO Rho GTPase Activating Protein 3 was found to be neuroprotective. In conclusion, these genes could play important roles in inflammasome signalling in neurons, which makes them promising therapeutic targets for future drug development against neuroinflammation in Alzheimer's disease.
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Is Misdiagnosis of Type 1 Diabetes Mellitus in Malaysian Children a Common Phenomenon? Front Endocrinol (Lausanne) 2021; 12:606018. [PMID: 33763028 PMCID: PMC7982891 DOI: 10.3389/fendo.2021.606018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/25/2021] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Children with Type 1 diabetes (T1DM) commonly present in diabetic ketoacidosis (DKA) at initial diagnosis. This is likely due to several factors, one of which includes the propensity for T1DM to be misdiagnosed. The prevalence of misdiagnosis has been reported in non-Asian children with T1DM but not in Asian cohorts. AIM To report the rate of misdiagnosis and its associated risk factors in Malaysian children and adolescents with T1DM. METHODS A retrospective analysis of children with T1DM below 18 years of age over a 10 year period was conducted. RESULTS The cohort included 119 children (53.8% female) with a mean age 8.1 SD ± 3.9 years. 38.7% of cases were misdiagnosed, of which respiratory illnesses were the most common (37.0%) misdiagnosis. The rate of misdiagnosis remained the same over the 10 year period. Among the variables examined, younger age at presentation, DKA at presentation, healthcare professional (HCP) contact and admission to the intensive care unit were significantly different between the misdiagnosed and correctly diagnosed groups (p <0.05). CONCLUSION Misdiagnosis of T1DM occurs more frequently in Malaysian children <5 years of age. Misdiagnosed cases are at a higher risk of presenting in DKA with increased risk of ICU admission and more likely to have had prior HCP contact. Awareness of T1DM amongst healthcare professionals is crucial for early identification, prevention of DKA and reducing rates of misdiagnosis.
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The Antibacterial Agent Identified from Acidocella spp. in the Fluid of Nepenthes gracilis Against Multidrug-Resistant Klebsiella pneumoniae: A Functional Metagenomic Approach. Microb Drug Resist 2020; 27:1018-1028. [PMID: 33325795 DOI: 10.1089/mdr.2020.0311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Aims: The fluid of Nepenthes gracilis harbors diverse bacterial taxa that could serve as a gene pool for the discovery of the new genre of antimicrobial agents against multidrug-resistant Klebsiella pneumoniae. The aim of this study was to explore the presence of antibacterial genes in the fluids of N. gracilis growing in the wild. Methods: Using functional metagenomic approach, fosmid clones were isolated and screened for antibacterial activity against three strains of K. pneumoniae. A clone that exhibited the most potent antibacterial activity was sent for sequencing to identify the genes responsible for the observed activity. The secondary metabolites secreted by the selected clone was sequentially extracted using hexane, chloroform, and ethyl acetate. The chemical profiles of a clone (C6) hexane extract were determined by gas chromatography/mass spectrometry (GC-MS). Results: Fosmid clone C6 from the fluid of pitcher plant that exhibited antibacterial activity against three strains of K. pneumoniae was isolated using functional metagenome approach. A majority of the open reading frames detected from C6 were affiliated with the largely understudied Acidocella genus. Among them, the gene that encodes for coproporphyrinogen III oxidase in the heme biosynthesis pathway could be involved in the observed antibacterial activity. Based on the GC-MS analysis, the identities of the putative bioactive compounds were 2,5-di-tert-butylphenol and 1-ethyl-2-methyl cyclododecane. Conclusions: The gene that encodes for coproporphyrinogen III oxidase in the heme biosynthesis pathway as well as the secondary metabolites, namely 2,5-di-tert-butylphenol and 1-ethyl-2-methyl cyclododecane could be the potential antibacterial molecules responsible for the antibacterial activity of C6.
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The effects of NLRP3 inflammasome inhibition by MCC950 on LPS-induced pancreatic adenocarcinoma inflammation. J Cancer Res Clin Oncol 2020; 146:2219-2229. [PMID: 32507974 DOI: 10.1007/s00432-020-03274-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 05/23/2020] [Indexed: 02/05/2023]
Abstract
PURPOSE Pancreatic cancer is a lethal form of cancer that can be triggered by prolonged or acute inflammation of the pancreas. Inflammation have been shown to be regulated by a group of key protein molecules known as the inflammasomes. The NLRP3 inflammasome is the most studied inflammasome and have been strongly implicated to regulate cancer cell proliferation. Therefore, this study aimed to examine the regulation of NLRP3 inflammasome under LPS-induced inflammation and its role in modulating cell proliferation in a panel of pancreatic cancer cells. METHODS The effects of LPS-induced NLRP3 activation in the presence or absence of MCC950, NLRP3-specific inhibitor, was tested on a panel of three pancreatic cancer cell lines (SW1990, PANC1 and Panc10.05). Western blotting, cell viability kits and ELISA kits were used to examine the effects of LPS-induced NLRP3 activation and inhibition by MCC950 on NLRP3 expression, cell viability, caspase-1 activity and cytokine IL-1β, respectively. RESULTS LPS-induced inflammation in the presence of ATP activates NLRP3 that subsequently increases pancreatic cancer cell proliferation by increasing caspase-1 activity leading to overall production of IL-1β. The inhibition of the NLRP3 inflammasome activation via the specific NLRP3 antagonist MCC950 was able to reduce the cell viability of pancreatic cancer cells. However, the efficacy of MCC950 varies between cell types which is most probably due to the difference in ASC expressions which have a different role in inflammasome activation. CONCLUSION There is a dynamic interaction between inflammasome that regulates inflammasome-mediated inflammation in pancreatic adenocarcinoma cells.
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Clinical features, disease activity and outcomes of Malaysian children with paediatric systemic lupus erythematosus: A cohort from a tertiary centre. Lupus 2020; 29:1106-1114. [PMID: 32631203 DOI: 10.1177/0961203320939185] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND Paediatric systemic lupus erythematosus is a rare autoimmune disease with a wide spectrum of clinical presentation in different populations. We present a cohort of paediatric systemic lupus erythematosus in Malaysia where the disease features and outcomes are still largely unknown. METHODS A retrospective review of all paediatric systemic lupus erythematosus patients with at least 6 months follow-up at Selayang Hospital from 2004 to 2016. Epidemiological, clinical and outcome data were collected and analysed. RESULTS A total of 141 paediatric systemic lupus erythematosus patients, 87.9% females, were followed up for a median 6.3 years (interquartile range 3.6-9.0). The median age at diagnosis was 10.8 years (interquartile range 9.0-12.0 years), positive family history of systemic lupus erythematosus was present in 12.1% and the majority (61.7%) were of Malay ethnicity. Common presentations included fever (87.2%), vasculitic rash (72.3%) and lethargy (69.5%). At diagnosis, leukopenia (51.1%), thrombocytopenia (41.8%) and cutaneous lupus (56%) predominate with significant renal involvement (39.7%). Renal (45.4%), liver (26%) and the central nervous system (17%) were important major organs involved during the course of the disease. At diagnosis, almost all (99.3%) patients had high disease activity (mean Systemic Lupus Erythematosus Disease Activity Index score 20.1 ± 9.6). The majority (62.4%) achieved remission or low disease activity after 6 months, maintained over the next 10 years. Damage occurred early (39.1% at 1 year) and increased with time. Ocular damage was the most common side effect (29%) and was predominantly corticosteroid related (93%). Growth retardation was significant (38.2%) with no gonadal failure or secondary malignancies. End-stage renal disease occurred in 3.1% patients whereas 53.1% had sustained renal remission. Overall mortality was 1.4%. CONCLUSION Despite high disease activity at diagnosis, the majority had good sustained response to treatment with low overall mortality. However, there was progressive accrual of organ damage, highlighting the need for further research and refinements into therapies for paediatric systemic lupus erythematosus.
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Synergistic Antibacterial Activity Between 1,4-Naphthoquinone and β-Lactam Antibiotics Against Methicillin-Resistant Staphylococcus aureus. Microb Drug Resist 2020; 27:234-240. [PMID: 32589487 DOI: 10.1089/mdr.2020.0178] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Aims: Currently, limited antibiotics are available to treat methicillin-resistant Staphylococcus aureus (MRSA) infections. One approach is the use of adjuvants in antibiotic therapy. 1,4-Naphthoquinones are naturally occurring alkaloids shown to have antibacterial properties. The objective of this study is to investigate the synergy between 1,4-naphthoquinone and selected β-lactam antibiotics and to evaluate the potential use of 1,4-naphthoquinone as an adjuvant in antibiotic treatment against MRSA infections. Methods: The antibacterial activity of 1,4-naphthoquinone and plumbagin was tested against nine pathogenic bacterial strains using the microdilution broth method. The interactions between 1,4-naphthoquinone and three antibiotics (cefuroxime, cefotaxime, and imipenem) were estimated by calculating the fractional inhibitory concentration of the combination. Results: The compounds 1,4-naphthoquinone and plumbagin exhibited a broad range of bacteriostatic and bactericidal effects against both Gram-positive and Gram-negative bacteria. The interaction between 1,4-naphthoquinone and imipenem, cefuroxime, and cefotaxime was synergistic against methicillin-sensitive Staphylococcus aureus and MRSA clinical strains. Against ATCC-cultured MRSA, a synergistic effect was observed between 1,4-naphthoquinone and cefotaxime. However, combination with imipenem only produced an additive effect, and an antagonistic action was observed between 1,4-naphthoquinone and cefuroxime. Conclusions: Although individually less potent than common antibiotics, 1,4-naphthoquinone acts synergistically with imipenem, cefuroxime, and cefotaxime against MRSA clinical strains and could potentially be used in adjuvant-antibiotic therapy against multidrug resistant bacteria.
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Piper sarmentosum Roxb. Root Extracts Confer Neuroprotection by Attenuating Beta Amyloid-Induced Pro-Inflammatory Cytokines Released from Microglial Cells. Curr Alzheimer Res 2019; 16:251-260. [DOI: 10.2174/1567205016666190228124630] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 01/11/2019] [Accepted: 02/08/2019] [Indexed: 12/13/2022]
Abstract
<P>Background: Alzheimer’s disease (AD) is a multifactorial neurodegenerative disorder that
eventually leads to severe cognitive impairment. Although the exact etiologies of AD still remain elusive,
increasing evidence suggests that neuroinflammation cascades mediated by microglial cells are
associated with AD. Piper sarmentosum Roxb. (PS) is a medicinal plant reported to possess various biological
properties, including anti-inflammatory, anti-psychotic and anti-oxidant activity. However, little
is known about the anti-inflammatory activity of PS roots despite their traditional use to treat inflammatory-
mediated ailments.
Objective: This study aimed to evaluate the anti-inflammatory and neuroprotective properties of extracts
obtained from the roots of PS against beta-amyloid (Aβ)-induced microglial toxicity associated with the
production of pro-inflammatory mediators.
Method: BV2 microglial cells were treated with hexane (RHXN), dichloromethane (RDCM), ethyl acetate
(REA) and methanol (RMEOH) extracts of the roots of PS prior to activation by Aβ. The production and
mRNA expression of pro-inflammatory mediators were evaluated by Griess reagent, ELISA kits and
RT-qPCR respectively. The phosphorylation status of p38α MAPK was determined via western blot assay.
BV2 conditioned medium was used to treat SH-SY5Y neuroblastoma cells and the neuroprotective
effect was assessed using MTT assay.
Results: PS root extracts, in particular RMEOH significantly attenuated the production and mRNA expression
of IL-1β, IL-6 and TNF-α in Aβ-induced BV2 microglial cells. In addition, RHXN, REA and
RMEOH extracts significantly reduced nitric oxide (NO) level and the inhibition of NO production was
correlated with the total phenolic content of the extracts. Further mechanistic studies suggested that PS
root extracts attenuated the production of cytokines by regulating the phosphorylation of p38α MAPK in
microglia. Importantly, PS root extracts have protective effects against Aβ-induced indirect neurotoxicity
either by inhibiting the production of NO, IL-1β, IL-6, and TNF-α in BV2 cells or by protecting SHSY5Y
cells against these inflammatory mediators.
Conclusions: These findings provided evidence that PS root extracts confer neuroprotection against Aβ-
induced microglial toxicity associated with the production of pro-inflammatory mediators and may be a
potential therapeutic agent for inflammation-related neurological conditions including Alzheimer’s disease
(AD).</P>
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The NLRP3 inflammasome is involved in the neuroprotective mechanism of neural stem cells against microglia-mediated toxicity in SH-SY5Y cells via the attenuation of tau hyperphosphorylation and amyloidogenesis. Neurotoxicology 2018; 70:91-98. [PMID: 30408495 DOI: 10.1016/j.neuro.2018.11.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 08/17/2018] [Accepted: 11/02/2018] [Indexed: 01/23/2023]
Abstract
The cognitive impairment caused by Alzheimer's disease (AD) is associated with beta-amyloid (Aβ) and tau proteins, and is accompanied by inflammation. Recently, a novel inflammasome signaling pathway has been uncovered. Inflammasomes are implicated in the execution of inflammatory responses and pyroptotic death leading to neurodegeneration. Thus, the inflammasome signaling pathway could be a potential therapeutic target for AD. Neural stem cells (NSCs) are multipotent cells that can self-renew and differentiate into distinct neural cells. NSC therapy has been considered to be a promising therapeutic approach in protecting the central nervous system and restoring it following damage. However, the mechanisms involved remain unclear. The aims of this study were to investigate the protective effects of NE4C neural stem cells against microglia-mediated neurotoxicity and to explore molecular mechanisms mediating their actions. NE4C decreased the levels of caspase-1 and IL-1β, and attenuated the level of the NLRP3 inflammasome and its associated protein adapter, apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC) in LPS-stimulated BV2 microglial cells, possibly by regulating the phosphorylation of p38α MAPK. The conditioned media obtained from co-culture of LPS-stimulated BV2 and NE4C cells exhibited protective effects on SH-SY5Y cells against microglia-mediated neurotoxicity; this was associated with an attenuation of tau phosphorylation and amyloidogenesis and accompanied by down-regulation of GSK-3β and p38α MAPK signalling pathways. In conclusion, the present study suggested that NSC therapy could be a potential strategy against microglia-mediated neurotoxicity. NSCs regulate NLRP3 activation and IL-1β secretion, which are critical in the initiation of the inflammatory responses, hence preventing the release of neurotoxic pro-inflammatory factors by microglia. This eventually reduces tau hyperphosphylation and amyloidogenesis, possibly through the regulation of GSK-3β and p38α MAPK signalling pathways, and thus protects SH-SY5Y cells against microglia-mediated neurotoxicity.
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Abstract
BACKGROUND Autophagy is a process devoted to degrade and recycle cellular components inside mammalian cells through lysosomal system. It plays a main function in the pathophysiology of several diseases. In type 2 diabetes, works demonstrated the dual functions of autophagy in diabetes biology. Studies had approved the role of autophagy in promoting different routes for movement of integral membrane proteins to the plasma membrane. But its role in regulation of GLUT4 trafficking has not been widely observed. In normal conditions, insulin promotes GLUT4 translocation from intracellular membrane compartments to the plasma membrane, while in type 2 diabetes defects occur in this translocation. METHOD Intriguing evidences discussed the contribution of different intracellular compartments in autophagy membrane formation. Furthermore, autophagy serves to mobilise membranes within cells, thereby promoting cytoplasmic components reorganisation. The intent of this review is to focus on the possibility of autophagy to act as a carrier for GLUT4 through regulating GLUT4 endocytosis, intracellular trafficking in different compartments, and translocation to cell membrane. RESULTS The common themes of autophagy and GLUT4 have been highlighted. The review discussed the overlapping of endocytosis mechanism and intracellular compartments, and has shown that autophagy and GLUT4 utilise similar proteins (SNAREs) which are used for exocytosis. On top of that, PI3K and AMPK also control both autophagy and GLUT4. CONCLUSION The control of GLUT4 trafficking through autophagy could be a promising field for treating type 2 diabetes.
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Piper sarmentosum Roxb. confers neuroprotection on beta-amyloid (Aβ)-induced microglia-mediated neuroinflammation and attenuates tau hyperphosphorylation in SH-SY5Y cells. JOURNAL OF ETHNOPHARMACOLOGY 2018; 217:187-194. [PMID: 29462698 DOI: 10.1016/j.jep.2018.02.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 02/13/2018] [Accepted: 02/16/2018] [Indexed: 06/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Piper sarmentosum Roxb. (PS), belonging to Piperaceae family, is an edible plant with medicinal properties. It is traditionally used by the Malays to treat headache and boost memory. Pharmacological studies revealed that PS exhibits anti-inflammatory, anti-oxidant, anti-acetylcholinesterase, and anti-depressant-like effects. In view of this, the present study aimed to investigate the anti-inflammatory actions of PS and its potential neuroprotective effects against beta-amyloid (Aβ)-induced microglia-mediated neurotoxicity. MATERIALS AND METHODS The inhibitory effects of hexane (LHXN), dichloromethane (LDCM), ethyl acetate (LEA) and methanol (LMEOH) extracts from leaves of PS on Aβ-induced production and mRNA expression of pro-inflammatory mediators in BV-2 microglial cells were assessed using colorimetric assay with Griess reagent, ELISA kit and real-time RT-PCR respectively. Subsequently, MTT reduction assay was used to evaluate the neuroprotective effects of PS leaf extracts against Aβ-induced microglia-mediated neurotoxicity in SH-SY5Y neuroblastoma cells. The levels of tau proteins phosphorylated at threonine 231 (pT231) and total tau proteins (T-tau) were determined using ELISA kits. RESULTS Polar extracts of PS leaves (LEA and LMEOH) reduced the Aβ-induced secretion of pro-inflammatory cytokines (IL-1β and TNF-α) in BV-2 cells by downregulating the mRNA expressions of pro-inflammatory cytokines. The inhibition of nitric oxide (NO) production could be due to the free radical scavenging activity of the extracts. In addition, conditioned media from Aβ-induced BV-2 cells pre-treated with LEA and LMEOH protected SH-SY5Y cells against microglia-mediated neurotoxicity. Further mechanistic study suggested that the neuroprotective effects were associated with the downregulation of phosphorylated tau proteins. CONCLUSIONS The present study suggests that polar extracts of PS leaves confer neuroprotection against Aβ-induced microglia-mediated neurotoxicity in SH-SY5Y cells by attenuating tau hyperphosphorylation through their anti-inflammatory actions and could be a potential therapeutic agent for Alzheimer's disease.
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Galloylated flavonol rhamnosides from the leaves of Calliandra tergemina with antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). PHYTOCHEMISTRY 2014; 107:148-154. [PMID: 25174555 DOI: 10.1016/j.phytochem.2014.07.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 07/18/2014] [Accepted: 07/19/2014] [Indexed: 06/03/2023]
Abstract
Galloylated flavonol rhamnosides identified as kaempferol-3-O-(2″,3″,4″-tri-O-galloyl)-α-l-rhamnopyranoside, quercetin-3-O-(3″,4″-di-O-galloyl)-α-l-rhamnopyranoside, and quercetin-3-O-(2″,3″,4″-tri-O-galloyl)-α-l-rhamnopyranoside, together with five known galloylated and non-galloylated flavonol rhamnosides, were isolated from leaves of Calliandra tergemina (L.) Benth. Their structures were established using spectroscopic methods and their antibacterial activities against methicillin-resistant Staphylococcus aureus (MRSA) were evaluated by a microdilution method.
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Assessment of phytochemical content, polyphenolic composition, antioxidant and antibacterial activities of Leguminosae medicinal plants in Peninsular Malaysia. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 11:12. [PMID: 21306653 PMCID: PMC3045388 DOI: 10.1186/1472-6882-11-12] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Accepted: 02/10/2011] [Indexed: 11/10/2022]
Abstract
Background Many medicinal plants from Leguminosae family can be found easily in Malaysia. These plants have been used as traditional medicines by local ethnic groups, where they are prepared as decoction, pastes for wound infections, and some have been eaten as salad. This paper focused on the assessment of antioxidant potential, antibacterial activity and classes of phytochemicals of nine plants from the Leguminosae family. Methods Acacia auriculiformis, Bauhinia kockiana, Bauhinia purpurea, Caesalpinia pulcherrima, Calliandra tergemina, Cassia surattensis, Leucaena leucocephala, Peltophorum pterocarpum, and Samanea saman were extracted with aqueous methanol and dichloromethane:methanol mixture to test for antioxidant and antibacterial activities. The Folin-Ciocalteu assay was conducted to quantify the total phenolic content and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay was used to determine the free radical quenching capacity. Antibacterial activity was assessed using disc diffusion (Kirby-Bauer) assay. Screening for major classes of phytochemical was done using standard chemical tests. Results B. kockiana flowers and C. pulcherrima leaves contained high total phenolic content (TPC) and strong DPPH radical scavenging ability with TPC of 8280 ± 498 mg GAE/100 g, IC50 of 27.0 ± 5.0 μg/mL and TPC of 5030 ± 602 mg GAE/100 g, IC50 of 50.0 ± 5.0 μg/mL respectively. Positive correlation was observed between TPC and free radical scavenging ability. Most extracts showed antibacterial activity against Gram positive bacteria at 1 mg, while none showed activity against Gram negative bacteria at the same dose. All extracts (except Samanea saman flower) showed antibacterial activity against two strains of methicillin resistant Staphylococcus aureus (MRSA) with MID values ranging between 100 μg/disc and 500 μg/disc. Conclusion The potential source of antioxidant and antibacterial agents, especially for MRSA infection treatments were found in B. kockiana, C. pulcherrima, C. tergemina and P. pterocarpum. These preliminary results would be a guide in the selection of potential candidates for further pharmacological study and in search of new drug candidate in treating MRSA infections.
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