27 results on '"Neel R Nabar"'
Search Results
2. Cell therapy: a safe and efficacious therapeutic treatment for Alzheimer's disease in APP+PS1 mice.
- Author
-
Neel R Nabar, Fang Yuan, Xiaoyang Lin, Li Wang, Ge Bai, Jonathan Mayl, Yaqiong Li, Shu-Feng Zhou, Jinhuan Wang, Jianfeng Cai, and Chuanhai Cao
- Subjects
Medicine ,Science - Abstract
Previously, our lab was the first to report the use of antigen-sensitized dendritic cells as a vaccine against Alzheimer's disease (AD). In preparation of this vaccine, we sensitized the isolated dendritic cells ex vivo with Aβ peptide, and administered these sensitized dendritic cells as a therapeutic agent. This form of cell therapy has had success in preventing and/or slowing the rate of cognitive decline when administered prior to the appearance of Aβ plaques in PDAPP mice, but has not been tested in 2 × Tg models. Herein, we test the efficacy and safety of this vaccine in halting and reversing Alzheimer's pathology in 9-month-old APP + PS1 mice. The results showed that administration of this vaccine elicits a long-lasting antibody titer, which correlated well with a reduction of Aβ burden upon histological analysis. Cognitive function in transgenic responders to the vaccine was rescued to levels similar to those found in non-transgenic mice, indicating that the vaccine is capable of providing therapeutic benefit in APP+PS1 mice when administered after the onset of AD pathology. The vaccine also shows indications of circumventing past safety problems observed in AD immunotherapy, as Th1 pro-inflammatory cytokines were not elevated after long-term vaccine administration. Moreover, microhemorrhaging and T-cell infiltration into the brain are not observed in any of the treated subjects. All in all, this vaccine has many advantages over contemporary vaccines against Alzheimer's disease, and may lead to a viable treatment for the disease in the future.
- Published
- 2012
- Full Text
- View/download PDF
3. Proteomic response to acupuncture treatment in spontaneously hypertensive rats.
- Author
-
Xinsheng Lai, Jiayou Wang, Neel R Nabar, Sanqiang Pan, Chunzhi Tang, Yong Huang, Mufeng Hao, Zhonghua Yang, Chunmei Ma, Jin Zhang, Helen Chew, Zhenquan He, Junjun Yang, Baogui Su, Jian Zhang, Jun Liang, Kevin B Sneed, and Shu-Feng Zhou
- Subjects
Medicine ,Science - Abstract
Previous animal and clinical studies have shown that acupuncture is an effective alternative treatment in the management of hypertension, but the mechanism is unclear. This study investigated the proteomic response in the nervous system to treatment at the Taichong (LR3) acupoint in spontaneously hypertensive rats (SHRs). Unanesthetized rats were subject to 5-min daily acupuncture treatment for 7 days. Blood pressure was monitored over 7 days. After euthanasia on the 7(th) day, rat medullas were dissected, homogenized, and subject to 2D gel electrophoresis and MALDI-TOF analysis. The results indicate that blood pressure stabilized after the 5th day of acupuncture, and compared with non-acupoint treatment, Taichong-acupunctured rat's systolic pressure was reduced significantly (P
- Published
- 2012
- Full Text
- View/download PDF
4. AKT Regulates NLRP3 Inflammasome Activation by Phosphorylating NLRP3 Serine 5
- Author
-
Wei Zhao, Il-Young Hwang, John H. Kehrl, Kathleen Harrison, Min Wang, Neel R. Nabar, and Chong-Shan Shi
- Subjects
Proteasome Endopeptidase Complex ,Inflammasomes ,Ubiquitin-Protein Ligases ,Interleukin-1beta ,Immunology ,Phosphatase ,Article ,Tripartite Motif Proteins ,Dephosphorylation ,Mice ,03 medical and health sciences ,0302 clinical medicine ,NLR Family, Pyrin Domain-Containing 3 Protein ,Animals ,Immunology and Allergy ,Phosphorylation ,Protein kinase A ,Protein kinase B ,integumentary system ,biology ,Chemistry ,Caspase 1 ,Interleukin-18 ,Ubiquitination ,Protein phosphatase 2 ,Ubiquitin ligase ,Cell biology ,Proteolysis ,biology.protein ,Proto-Oncogene Proteins c-akt ,Inflammasome complex ,030215 immunology - Abstract
The cytosolic pattern recognition receptor NLRP3 senses host-derived danger signals and certain microbe-derived products in both humans and rodents. NLRP3 activation assembles an inflammasome complex that contains the adapter proteins ASC and caspase-1, whose activation triggers the maturation and release of the proinflammatory cytokines IL-1β and IL-18. S5 phosphorylation of NLRP3 prevents its oligomerization and activation, whereas dephosphorylation of this residue by the phosphatase PP2A allows NLRP3 activation. However, the protein kinase that mediates NLRP3 S5 phosphorylation is unknown. In this study, we show that AKT associates with NLRP3 and phosphorylates it on S5, limiting NLRP3 oligomerization. This phosphorylation event also stabilizes NLRP3 by reducing its ubiquitination on lysine 496, which inhibits its proteasome-mediated degradation by the E3 ligase Trim31. Pharmacologic manipulation of AKT kinase activity reciprocally modulates NLRP3 inflammasome-mediated IL-1β production. Inhibition of AKT reduced IL-1β production following the i.p. injection of LPS into mice. We propose that AKT, Trim31, and PP2A together modulate NLRP3 protein levels and the tendency to oligomerize, thereby setting a tightly regulated threshold for NLRP3 activation.
- Published
- 2020
5. LRRK2 is required for CD38-mediated NAADP-Ca
- Author
-
Neel R, Nabar, Christopher N, Heijjer, Chong-Shan, Shi, Il-Young, Hwang, Sundar, Ganesan, Mikael C I, Karlsson, and John H, Kehrl
- Subjects
Lipopolysaccharides ,Adenosine Diphosphate Ribose ,Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ,Leucine ,Autophagy ,Antibodies, Monoclonal ,Humans ,Calcium ,Parkinson Disease ,Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 ,Lysosomes ,NADP ,Transcription Factors - Abstract
CD38 is a cell surface receptor capable of generating calcium-mobilizing second messengers. It has been implicated in host defense and cancer biology, but signaling mechanisms downstream of CD38 remain unclear. Mutations in LRRK2 (leucine-rich repeat kinase 2) are the most common genetic cause of Parkinson disease; it is also a risk factor for Crohn disease, leprosy, and certain types of cancers. The pathogenesis of these diseases involves inflammation and macroautophagy/autophagy, processes both CD38 and LRRK2 are implicated in. Here, we mechanistically and functionally link CD38 and LRRK2 as upstream activators of TFEB (transcription factor EB), a host defense transcription factor and the master transcriptional regulator of the autophagy/lysosome machinery. In B-lymphocytes and macrophages, we show that CD38 and LRRK2 exist in a complex on the plasma membrane. Ligation of CD38 with the monoclonal antibody clone 90 results in internalization of the CD38-LRRK2 complex and its targeting to the endolysosomal system. This generates an NAADP-dependent calcium signal, which requires LRRK2 kinase activity, and results in the downstream activation of TFEB.
- Published
- 2021
6. Gαi2 Signaling Regulates Inflammasome Priming and Cytokine Production by Biasing Macrophage Phenotype Determination
- Author
-
Neel R. Nabar, Silke Sohn, Joe B. Blumer, John H. Kehrl, Chung Park, Mikael C. I. Karlsson, Il-Young Hwang, and Ali Vural
- Subjects
Inflammasomes ,medicine.medical_treatment ,Immunology ,Macrophage polarization ,Article ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,AIM2 ,0302 clinical medicine ,NLRC4 ,Heterotrimeric G protein ,medicine ,Animals ,Immunology and Allergy ,Receptor ,Cells, Cultured ,Mice, Knockout ,Chemistry ,Macrophages ,Inflammasome ,Cell biology ,Mice, Inbred C57BL ,Phenotype ,Cytokine ,Cytokines ,GTP-Binding Protein alpha Subunit, Gi2 ,Signal Transduction ,030215 immunology ,medicine.drug - Abstract
Macrophages exist as innate immune subsets that exhibit phenotypic heterogeneity and functional plasticity. Their phenotypes are dictated by inputs from the tissue microenvironment. G-protein–coupled receptors are essential in transducing signals from the microenvironment, and heterotrimeric Gα signaling links these receptors to downstream effectors. Several Gαi-coupled G-protein–coupled receptors have been implicated in macrophage polarization. In this study, we use genetically modified mice to investigate the role of Gαi2 on inflammasome activity and macrophage polarization. We report that Gαi2 in murine bone marrow–derived macrophages (BMDMs) regulates IL-1β release after activation of the NLRP3, AIM2, and NLRC4 inflammasomes. We show this regulation stems from the biased polarity of Gαi2 deficient (Gnai2−/−) and RGS-insensitive Gαi2 (Gnai2G184S/G184S) BMDMs. We determined that although Gnai2G184S/G184S BMDMs (excess Gαi2 signaling) have a tendency toward classically activated proinflammatory (M1) phenotype, Gnai2−/− BMDMs (Gαi2 deficient) are biased toward alternatively activated anti-inflammatory (M2) phenotype. Finally, we find that Gαi2-deficient macrophages have increased Akt activation and IFN-β production but defects in ERK1/2 and STAT3 activation after LPS stimulation. Gαi2-deficient macrophages also exhibit increased STAT6 activation after IL-4 stimulation. In summary, our data indicates that excess Gαi2 signaling promotes an M1 macrophage phenotype, whereas Gαi2 signaling deficiency promotes an M2 phenotype. Understanding Gαi2-mediated effects on macrophage polarization may bring to light insights regarding disease pathogenesis and the reprogramming of macrophages for the development of novel therapeutics.
- Published
- 2019
7. LRRK2 is required for CD38-mediated NAADP-Ca2+ signaling and the downstream activation of TFEB (transcription factor EB) in immune cells
- Author
-
Chong-Shan Shi, Neel R. Nabar, John H. Kehrl, Christopher N Heijjer, Il-Young Hwang, Sundar Ganesan, and Mikael C. I. Karlsson
- Subjects
Innate immune system ,Autophagy ,Cell Biology ,Biology ,LRRK2 ,nervous system diseases ,Cell biology ,medicine.anatomical_structure ,Lysosome ,Second messenger system ,medicine ,TFEB ,Kinase activity ,Molecular Biology ,Transcription factor - Abstract
CD38 is a cell surface receptor capable of generating calcium-mobilizing second messengers. It has been implicated in host defense and cancer biology, but signaling mechanisms downstream of CD38 remain unclear. Mutations in LRRK2 (leucine-rich repeat kinase 2) are the most common genetic cause of Parkinson disease; it is also a risk factor for Crohn disease, leprosy, and certain types of cancers. The pathogenesis of these diseases involves inflammation and macroautophagy/autophagy, processes both CD38 and LRRK2 are implicated in. Here, we mechanistically and functionally link CD38 and LRRK2 as upstream activators of TFEB (transcription factor EB), a host defense transcription factor and the master transcriptional regulator of the autophagy/lysosome machinery. In B-lymphocytes and macrophages, we show that CD38 and LRRK2 exist in a complex on the plasma membrane. Ligation of CD38 with the monoclonal antibody clone 90 results in internalization of the CD38-LRRK2 complex and its targeting to the endolysosomal system. This generates an NAADP-dependent calcium signal, which requires LRRK2 kinase activity, and results in the downstream activation of TFEB. lrrk2 KO macrophages accordingly have TFEB activation defects following CD38 or LPS stimulation and fail to switch to glycolytic metabolism after LPS treatment. In overexpression models, the pathogenic LRRK2G2019S mutant promotes hyperactivation of TFEB even in the absence of CD38, both by stabilizing TFEB and promoting its nuclear translocation via aberrant calcium signaling. In sum, we have identified a physiological CD38-LRRK2-TFEB signaling axis in immune cells. The common pathogenic mutant, LRRK2G2019S, appears to hijack this pathway. Abbreviations:ADPR: ADP-ribose; AMPK: AMP-activated protein kinase; BMDM: bone marrow-derived macrophage; cADPR: cyclic-ADP-ribose; COR: C-terminal of ROC; CTSD: cathepsin D; ECAR: extracellular acidification rate; EDTA: ethylenediaminetetraacetic acid; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; GPN: Gly-Phe ��-naphthylamide; GSK3B/GSK3��: glycogen synthase kinase 3 beta; GTP: guanosine triphosphate; KD: knockdown; LAMP1: lysosomal-associated membrane protein 1; LRR: leucine rich repeat; LRRK2: leucine rich repeat kinase 2; mAb: monoclonal antibody; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; MAPK/ERK: mitogen-activated protein kinase; MCOLN1: mucolipin 1; MFI: mean fluorescence intensity; mRNA: messenger RNA; MTOR: mechanistic target of rapamycin kinase; NAADP: nicotinic acid adenine dinucleotide phosphate; NAD: nicotinamide adenine dinucleotide; NADP: nicotinamide adenine dinucleotide phosphate; PD: Parkinson disease; PPP3CB: protein phosphatase 3, catalytic subunit, beta isoform; q-RT-PCR: quantitative reverse transcription polymerase chain reaction; ROC: Ras of complex; siRNA: small interfering RNA; SQSTM1/p62: sequestome 1; TFEB: transcription factor EB; TPCN: two pore channel; TRPM2: transient receptor potential cation channel, subfamily M, member 2; ZKSCAN3: zinc finger with KRAB and SCAN domains 3
- Published
- 2021
- Full Text
- View/download PDF
8. Novel approach for low-dose pulmonary delivery of hydroxychloroquine in COVID-19
- Author
-
Safa C. Fassihi, Neel R. Nabar, and Reza Fassihi
- Subjects
2019-20 coronavirus outbreak ,Coronavirus disease 2019 (COVID-19) ,Pneumonia, Viral ,Nebulization ,Betacoronavirus ,Drug Delivery Systems ,The Pharmacology of Covid‐19 ,Chloroquine ,COVID‐19 ,Pandemic ,Medicine ,Humans ,Respiratory pharmacology ,Lung ,Pandemics ,Letter to the Editor ,Pharmacology ,business.industry ,SARS-CoV-2 ,Low dose ,COVID-19 ,Hydroxychloroquine ,Virology ,COVID-19 Drug Treatment ,Drug delivery ,business ,Coronavirus Infections ,medicine.drug - Published
- 2020
9. Inhibition of angiotensin II receptor I prevents inflammation and bone loss in periodontitis
- Author
-
Min Wang, Neel R. Nabar, Ye Tian, Yuan Yue, Jin-le Li, Xun Xiao, Handong Ding, Wei Wei, Zhaohui Liu, and Zheng Yang
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Angiotensin receptor ,Osteoclasts ,Inflammation ,Pathogenesis ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Humans ,Periodontitis ,Retrospective Studies ,Receptors, Angiotensin ,Angiotensin II receptor type 1 ,business.industry ,030206 dentistry ,medicine.disease ,Angiotensin II ,030104 developmental biology ,Losartan ,Endocrinology ,TLR4 ,Periodontics ,medicine.symptom ,business ,medicine.drug - Abstract
Background Periodontal disease is characterized by alveolar bone destruction and degenerative lesions of the periodontal ligament (PDL); it is initiated by bacterial infection of the oral cavity, but the clinical effects are secondary to an aberrant host immune response. Primary hypertension (PH), which causes significant morbidity and mortality worldwide, has also been shown to be an inflammatory disease characterized by aberrant immune cell infiltration and activation. Clinical retrospective studies have shown a link between PH and periodontitis with PH exacerbating periodontitis and vice versa, but the pathophysiologic mechanisms responsible for this remain unknown. Methods In this study, we investigate the underlying mechanisms behind PH exacerbation of periodontitis by using a bacteria-induced periodontitis model in normotensive and hypertensive (Nos3-/- ) mice treated with or without an Angiotensin II (Ang II) specific receptor 1 (AT1) antagonist, losartan. The histologic analyses including immunohistochemistry, immunofluorescence were carried out. The qRT-PCR and ELISAs were applied for the target gene and protein detection. Results We find that PH worsens bone resorption and PDL destruction in periodontitis and that treatment with losartan, rescues this. We also show that PH increases dendritic cell (DC) and osteoclast (OC) infiltration in periodontitis, which is also dependent on Ang II. Finally, we show that PH augments the pro-inflammatory state in periodontitis infiltrating DCs in an Ang II-dependent manner and use in vitro studies to show that Ang II directly augments DC Toll-like receptor 4 (TLR4) signaling. Conclusion Our studies show a central role for Ang II as a pro-inflammatory Toll-like receptor mediator in the pathogenesis of PH-exacerbated periodontitis, indicating that Ang II may be a reasonable target in patients with PH and periodontitis comorbidity.
- Published
- 2018
10. Autophagy and inflammasomes
- Author
-
Jacinta P.W. Thomas, Maria B. Sukkar, James Harris, Neel R. Nabar, Tali Lang, and John H. Kehrl
- Subjects
0301 basic medicine ,Inflammasomes ,Immunology ,Antigen presentation ,Caspase 1 ,Regulator ,NLR Proteins ,Biology ,Proinflammatory cytokine ,Mitochondrial Proteins ,Mice ,03 medical and health sciences ,AIM2 ,Downregulation and upregulation ,Autophagy ,medicine ,Animals ,Humans ,Molecular Biology ,Interleukin-18 ,Membrane Proteins ,Inflammasome ,Mitochondria ,Cell biology ,CARD Signaling Adaptor Proteins ,DNA-Binding Proteins ,Cytoskeletal Proteins ,030104 developmental biology ,Biochemistry ,Interleukin-1 ,medicine.drug - Abstract
© 2017 Elsevier Ltd Autophagy is a ubiquitous cellular mechanism for the targeted lysosomal degradation of various cytosolic constituents, from proteins to organelles. As an essential homeostatic mechanism, autophagy is upregulated in response to numerous environmental and pharmacological stimuli, including starvation, where it facilitates the recycling of essential amino acids. In addition, autophagy plays specific roles within the immune system; it serves as a source of peptides for antigen presentation, a mechanism for the engulfment and degradation of intracellular pathogens and as a key regulator of inflammatory cytokines. In particular, autophagy has been shown to play a number of roles in regulating inflammasome activation, from the removal of inflammasome-activating endogenous signals, to the sequestration and degradation of inflammasome components. Autophagy also plays a role in determining the fate of IL-1β, which is concentrated in autophagosomes. This review discusses a growing body of literature that suggests autophagy is a critical regulator of inflammasome activation and the subsequent release of IL-1 family cytokines.
- Published
- 2017
11. SARS-Coronavirus Open Reading Frame-8b triggers intracellular stress pathways and activates NLRP3 inflammasomes
- Author
-
John H. Kehrl, Chong-Shan Shi, Ning-Na Huang, and Neel R. Nabar
- Subjects
0301 basic medicine ,Cancer Research ,Programmed cell death ,Immunology ,medicine.disease_cause ,lcsh:RC254-282 ,Article ,Inflammasome ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Lysosome ,Cell death and immune response ,medicine ,lcsh:QH573-671 ,Coronavirus ,Innate immune system ,lcsh:Cytology ,Chemistry ,Cell Biology ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,3. Good health ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Unfolded protein response ,TFEB ,Intracellular ,medicine.drug - Abstract
The SARS (severe acute respiratory syndrome) outbreak was caused by a coronavirus (CoV) named the SARS-CoV. SARS pathology is propagated both by direct cytotoxic effects of the virus and aberrant activation of the innate immune response. Here, we identify several mechanisms by which a SARS-CoV open reading frame (ORF) activates intracellular stress pathways and targets the innate immune response. We show that ORF8b forms insoluble intracellular aggregates dependent on a valine at residue 77. Aggregated ORF8b induces endoplasmic reticulum (ER) stress, lysosomal damage, and subsequent activation of the master regulator of the autophagy and lysosome machinery, Transcription factor EB (TFEB). ORF8b causes cell death in epithelial cells, which is partially rescued by reducing its ability to aggregate. In macrophages, ORF8b robustly activates the NLRP3 inflammasome by providing a potent signal 2 required for activation. Mechanistically, ORF8b interacts directly with the Leucine Rich Repeat domain of NLRP3 and localizes with NLRP3 and ASC in cytosolic dot-like structures. ORF8b triggers cell death consistent with pyroptotic cell death in macrophages. While in those cells lacking NLRP3 accumulating ORF8b cytosolic aggregates cause ER stress, mitochondrial dysfunction, and caspase-independent cell death.
- Published
- 2019
12. The comparison of biocompatibility and osteoinductivity between multi-walled and single-walled carbon nanotube/PHBV composites
- Author
-
Liang Hao, Neel R. Nabar, Xun Xiao, Qin Shan, Weiyi Pan, Min Wang, Ye Tian, Yuan Yue, Shibing Deng, and Jin-le Li
- Subjects
Materials science ,Biocompatibility ,Cell Survival ,Polyesters ,Sonication ,Biomedical Engineering ,Biophysics ,Biocompatible Materials ,Bioengineering ,02 engineering and technology ,Carbon nanotube ,010402 general chemistry ,01 natural sciences ,law.invention ,Rats, Sprague-Dawley ,Biomaterials ,Tissue engineering ,law ,Materials Testing ,Animals ,Injection moulding ,Composite material ,Cells, Cultured ,Osteoblasts ,Tissue Engineering ,Nanotubes, Carbon ,Carbon chemistry ,Thermal decomposition ,021001 nanoscience & nanotechnology ,Rats ,0104 chemical sciences ,Animals, Newborn ,Femoral bone ,0210 nano-technology - Abstract
The applications of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) in tissue engineering have been widely studied. This study aimed to compare the biocompatibility and osteoinductivity of single-walled carbon nanotubes (SWCNTs)/PHBV composites with multi-walled CNTs (MWCNTs)/PHBV composites. CNTs were dispersed in PHBV by ultrasonication and composites were created using thermal injection moulding. In order to test their biocompatibility and osteoinductivity. Rat osteoblasts (rOBs) were then cultured and seeded on the composites. The composites were implanted in rat femoral bone defects. Our results showed that lower weight percentages of SWCNTs and MWCNTs (2-4%) improved both their mechanical and thermal decomposition properties. However, further reduction of rOBs cell death was observed in MWCNTs/PHBV. SWCNTs were shown to upregulate the expression of Runx-2 and Bmp-2 in early stage significantly, while MWCNTs showed a stronger long-term effect on Opn and Ocn. The in vivo result was that MWCNTs/PHBV composites induced intact rounding new bone, increased integration with new bone, and earlier completed bone remodeling when compared with SWCNTs. Immunohistochemistry also detected higher expression of RUNX-2 around MWCNTs/PHBV composites. In conclusion, there were no differences observed between SWCNTs and MWCNTs in the reinforcement of PHBV, while MWCNTs/PHBV composites showed better biocompatibility and osteoinductivity both in vitro and in vivo.
- Published
- 2018
13. Low-intensity pulsed ultrasound upregulates pro-myelination indicators of Schwann cells enhanced by co-culture with adipose-derived stem cells
- Author
-
Xiaoxiao Cai, Xingmei Yang, Liang Zhang, Xun Xiao, Jingle Li, Jingyi Huo, Neel R. Nabar, Yunfeng Lin, Min Wang, Yuan Yue, Dongjiao Zhang, and Hao Liang
- Subjects
0301 basic medicine ,Receptor, ErbB-3 ,Neuregulin-1 ,Ultrasonic Therapy ,Schwann cell ,Adipose tissue ,Biology ,Low-intensity pulsed ultrasound ,Rats, Sprague-Dawley ,Andrology ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Peripheral Nerve Injuries ,medicine ,Animals ,ERBB3 ,RNA, Messenger ,Early Growth Response Protein 2 ,Myelin Sheath ,Regeneration (biology) ,Myelin Basic Protein ,Original Articles ,Cell Biology ,General Medicine ,Coculture Techniques ,Up-Regulation ,Myelin basic protein ,Adult Stem Cells ,030104 developmental biology ,medicine.anatomical_structure ,Adipose Tissue ,Ultrasonic Waves ,Immunology ,biology.protein ,Female ,Schwann Cells ,Stem cell ,030217 neurology & neurosurgery - Abstract
Objectives Peripheral nerve injuries are a common occurrence, resulting in considerable patient suffering; it also represents a major economic burden on society. To improve treatment options following peripheral nerve injuries, scientists aim to find a way to promote Schwann cell (SC) myelination to help nerves to carry out their functions effectively. In this study, we investigated myelination ability of SCs, regulated by co-culture with adipose-derived stem cells (ASCs) or low-intensity pulsed ultrasound (LIPUS), and synergistic effects of combined treatments. Materials and methods Schwann cells were co-cultured with or without ASCs, and either left untreated or treated with LIPUS for 10 min/d for 1, 4 or 7 days. Effects of LIPUS and ASC co-culture on pro-myelination indicators of SCs were analysed by real-time PCR (RT-PCR), Western blotting and immunofluorescence staining (IF). Results Our results indicate that ASC-SC co-culture and LIPUS, together or individually, promoted mRNA levels of epidermal growth factor receptor 3 (EGFR3/ErbB3), neuregulin1 (NRG1), early growth response protein 2 (Egr2/Krox20) and myelin basic protein (MBP), with corresponding increases in protein levels of ErbB3, NRG1 and Krox20. Interestingly, combination of ASC-SC co-culture and LIPUS displayed the most remarkable effects. Conclusion We demonstrated that ASCs upregulated pro-myelination indicators of SCs by indirect contact (through co-culture) and that effects could be potentiated by LIPUS. We conclude that LIPUS, as a mechanical stress, may have potential in nerve regeneration with potential clinical relevance.
- Published
- 2016
14. SARS-Coronavirus Open Reading Frame-3a drives multimodal necrotic cell death
- Author
-
Yuan Yue, Il-Young Hwang, Chong-Shan Shi, Neel R. Nabar, Min Wang, Olena Kamenyeva, John H. Kehrl, and Xun Xiao
- Subjects
0301 basic medicine ,Cancer Research ,Endosome ,Inflammasomes ,Immunology ,Apoptosis ,Biology ,Severe Acute Respiratory Syndrome ,Article ,Cell Line ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,Necrosis ,Open Reading Frames ,Cell Line, Tumor ,medicine ,Autophagy ,Humans ,lcsh:QH573-671 ,skin and connective tissue diseases ,A549 cell ,lcsh:Cytology ,HEK 293 cells ,fungi ,Inflammasome ,Cell Biology ,Intracellular Membranes ,Cell biology ,body regions ,Open reading frame ,030104 developmental biology ,HEK293 Cells ,Severe acute respiratory syndrome-related coronavirus ,Cell culture ,A549 Cells ,Receptor-Interacting Protein Serine-Threonine Kinases ,TFEB ,Lysosomes ,medicine.drug ,HeLa Cells - Abstract
The molecular mechanisms underlying the severe lung pathology that occurs during SARS-CoV infections remain incompletely understood. The largest of the SARS-CoV accessory protein open reading frames (SARS 3a) oligomerizes, dynamically inserting into late endosomal, lysosomal, and trans-Golgi-network membranes. While previously implicated in a non-inflammatory apoptotic cell death pathway, here we extend the range of SARS 3a pathophysiologic targets by examining its effects on necrotic cell death pathways. We show that SARS 3a interacts with Receptor Interacting Protein 3 (Rip3), which augments the oligomerization of SARS 3a helping drive necrotic cell death. In addition, by inserting into lysosomal membranes SARS 3a triggers lysosomal damage and dysfunction. Consequently, Transcription Factor EB (TFEB) translocates to the nucleus increasing the transcription of autophagy- and lysosome-related genes. Finally, SARS 3a activates caspase-1 either directly or via an enhanced potassium efflux, which triggers NLRP3 inflammasome assembly. In summary, Rip3-mediated oligomerization of SARS 3a causes necrotic cell death, lysosomal damage, and caspase-1 activation—all likely contributing to the clinical manifestations of SARS-CoV infection.
- Published
- 2018
- Full Text
- View/download PDF
15. Inhibition of Ctsk alleviates periodontitis and comorbid rheumatoid arthritis via downregulation of the TLR9 signalling pathway
- Author
-
Min Wang, Liang Hao, Jie Ren, Handong Ding, Neel R. Nabar, Lili Xue, Weiyi Pan, Qiuyu Lu, Wei Wei, Zhaohui Liu, Wuwei Yin, and Li Yang
- Subjects
medicine.medical_treatment ,Cathepsin K ,Arthritis ,Down-Regulation ,Inflammation ,Comorbidity ,Bone resorption ,Arthritis, Rheumatoid ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Medicine ,Animals ,030212 general & internal medicine ,Periodontitis ,business.industry ,TLR9 ,030206 dentistry ,medicine.disease ,Cytokine ,Mice, Inbred DBA ,Rheumatoid arthritis ,Toll-Like Receptor 9 ,Immunology ,Periodontics ,medicine.symptom ,business - Abstract
Aim In this study, we investigate the mechanistic link between rheumatoid arthritis (RA) and periodontitis to identify a novel target (cathepsin K; Ctsk) for the treatment of comorbid periodontitis and RA. Methods An experimental model of periodontitis with arthritis was established in DBA/1 mice. We then tested the effect of BML-244, a specific inhibitor of Ctsk, by quantifying several inflammatory markers of TLR9 signalling both in vivo and in vitro. Results Our results showed that periodontitis-rheumatoid arthritis comorbidity causes severer periodontal bone and joint cartilage destruction than either disease alone. Inhibition of Ctsk reduced infiltration by dendritic cells and T cells and inflammatory cytokine production; these improvements alleviated the hard-tissue erosion in periodontitis and RA as measured by bone erosion in periodontal lesions and cartilage destruction in knee joints. Inhibition of Ctsk also decreased the expression of TLR4 and TLR9 in vivo, whereas in vitro experiments indicated that Ctsk is involved specifically in the production of cytokines in response to TLR9 engagement. Conclusion Our data reveal that periodontitis and RA may have additive pathological effects through dysregulation of the TLR9 pathway and that Ctsk is a critical mediator of this pathway and contributes to the pathogenesis of RA and periodontitis.
- Published
- 2018
16. Signaling by the Toll-Like Receptors Induces Autophagy Through Modification of Beclin 1
- Author
-
Neel R. Nabar, Chong-Shan Shi, and John H. Kehrl
- Subjects
0301 basic medicine ,Toll-like receptor ,Innate immune system ,Autophagy ,Pattern recognition receptor ,Signal transducing adaptor protein ,Biology ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Immune system ,TRIF ,030220 oncology & carcinogenesis ,Intracellular - Abstract
The innate immune system employs germline-encoded pattern recognition receptors (PRRs) that can detect pathogens and initiate the immune response. The Toll-like receptors (TLRs) are the best studied PRRs and they act by initiating an intracellular signaling cascade that is dependent on the adaptor proteins MyD88 and TRIF. This response activates the critical transcription factors NF-κB and IRF3, and functions to prime both the innate and adaptive immune effector cells for pathogen clearance. Macrophages are one of the major effector cell types of innate immunity. They help clear extracellular infections by phagocytosis and eventual phagosome–lysosome fusion, and intracellular infections by enclosing microbes in autophagic vesicles for delivery to the lysosome. Initiation of autophagy requires phosphatidylinositol 3-phosphate [PtdIns(3)P], which is generated by the phosphatidylinositol 3-kinase class III (PtdIns3KC3/Vps34) complex. This chapter discusses the detailed molecular mechanisms through which TLR signaling primes macrophages for intracellular pathogen clearance by initiating autophagy. We focus on Beclin 1, a key component of the PtdIsn3KC3 complex, which is recruited to the TLR signalosome upon TLR stimulation and subsequently posttranslationally modified to disrupt its binding with its inhibitor, Bcl-2.
- Published
- 2018
17. Contributors
- Author
-
Paolo A. Ascierto, Milena Bertolotti, William Borkowsky, Lisa M. Coussens, Audrey Esclatine, Lucia Festino, Anne A. Gershon, M.A. Hayat, Ming-Xiao He, You-Wen He, Nuhad K. Ibrahim, Chinnaswamy Jagannath, Wei Jia, John H. Kehrl, Arshad Khan, Girdhari Lal, Mark L. Lang, Shannon M. Liudahl, Marion Lussignol, Dante J. Marciani, Ian McLeod, James L. Murray, Neel R. Nabar, Lyse Norian, Rachael Orlandella, Sourav Paul, Pragya Rampuria, Chong-Shan Shi, Roberto Sitia, Martina Strudel, Vito Vanella, Yeldur P. Venkatesh, Jin Wang, and Chuanwei Yang
- Published
- 2018
18. Inflammasome Inhibition Links IRGM to Innate Immunity
- Author
-
John H. Kehrl and Neel R. Nabar
- Subjects
0303 health sciences ,Innate immune system ,integumentary system ,animal diseases ,Autophagy ,Cell ,Immune regulation ,chemical and pharmacologic phenomena ,Inflammasome ,Cell Biology ,Biology ,Cell biology ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,GTP-binding protein regulators ,Immunity ,IRGM ,medicine ,Molecular Biology ,030217 neurology & neurosurgery ,030304 developmental biology ,medicine.drug - Abstract
IRGM is a risk factor for several inflammatory diseases, yet no direct link to immune regulation had been shown. In this issue of Molecular Cell, Mehto et al. (2019) report that IRGM limits NLRP3 inflammasome activation—by both direct inhibition of NLRP3/ASC oligomerization and selective autophagic destruction of NLRP3/ASC.
- Published
- 2019
19. LOX-related collagen crosslink changes act as an initiator of bone fragility in a ZDF rats model
- Author
-
Jun Chen, Xun Xiao, Ye Tian, Zhaohui Liu, Min Wang, Neel R. Nabar, Liang Hao, and Jie Ren
- Subjects
musculoskeletal diseases ,0301 basic medicine ,Male ,medicine.medical_specialty ,Biophysics ,030209 endocrinology & metabolism ,Lysyl oxidase ,Type 2 diabetes ,Matrix (biology) ,Bone fragility ,Biochemistry ,Pathogenesis ,Protein-Lysine 6-Oxidase ,03 medical and health sciences ,0302 clinical medicine ,Diabetes mellitus ,Internal medicine ,medicine ,Animals ,Femur ,Molecular Biology ,chemistry.chemical_classification ,Cell Biology ,medicine.disease ,Zdf rats ,Rats ,Rats, Zucker ,030104 developmental biology ,Endocrinology ,Enzyme ,Cross-Linking Reagents ,chemistry ,Diabetes Mellitus, Type 2 ,Osteoporosis ,Collagen - Abstract
Diabetes mellitus type 2 (DM2) results in bone abnormalities that manifest as increased bone fragility. Bone consists of two phases, the mineral phase and the matrix phase, and disorders in both are seen in DM2. However, the phase in which DM2 mediated bone fragility is initiated is still unknown. In this study, a male Zucker diabetic fatty (fa/fa) (ZDF) rat model was used to investigate the underlying mechanism initiating DM2 mediated bone fragility. The fracture surface morphology, pre- and post-yield bone mechanical behavior, insoluble collagen volume, lysyl oxidase family (LOX) enzyme levels and correlation analysis was performed to determine the relationship between insoluble collagen and post-yield behavior. Four weeks after the induction of diabetes, insoluble collagen was decreased in only the matrix phase in diabetic rats. Consistently, mechanical testing of the bone showed changes only in post-yield behavior. Diabetic rats also had decreased levels of enzymes involved in insoluble collagen formation (LOX and LOXL1 families). Correlation analysis demonstrated that insoluble collagen was a positive regressor of post-yield displacement (R = 0.894, P
- Published
- 2017
20. Contributors
- Author
-
Amal O. Amer, Yenniffer Ávalos, Alexander Belyayev, Kyle Caution, Simone Cenci, Francesco Cecconi, Swati Choksi, Valentina Cianfanelli, Katherine L. Cook, Robert Clarke, Estelle Cornet-Boyaka, Mark S. Cragg, Duaa Dakhlallah, Jekaterina Erenpreisa, Masatoshi Esaki, Lynn G. Feun, Mark Y. Fink, Roberta A. Gottlieb, Jessie Y. Guo, Norifumi Harimoto, James Harris, M.A. Hayat, Toshihiko Hayashi, Maria P. Hernández-Cáceres, Toru Ikegami, Takashi Ikejima, Inna Inashkina, Shinji Itoh, Andrei I. Ivanov, John H. Kehrl, M.T. Kuo, Tali Lang, Raquel Franco Leal, Zhenggang Liu, Zhanna Lipatova, Jia Luo, Yoshihiko Maehara, Patricio Manque, Maria Markaki, Yoshihiro Matsumoto, Athansios Metaxakis, Olivia C. MeKee-Muir, Eugenia Morselli, Neel R. Nabar, Melissa Nassif, Dao Nguyen, Niccolò Pengo, Margherita Protasoni, Ryan C. Russell, Kristine Salmina, Niramol Savaraj, Nava Segev, Chong-Shan Shi, Ken Shirabe, Francesca A. Ramos Silva, Michelle L. Snyder, Maria B. Sukkar, Jan-Willem Taanman, Nektarios Tavernarakis, Lilian Toledo, Takeo Toshima, Allan Tsung, Medhi Wangpaichitr, Matthew R. Weichseldorfer, Theresa L. White, Ute Woelhbier, Chunjing Wu, Tomoharu Yoshizumi, Min You, Lemeng Zhang, and Yan Zhang
- Published
- 2017
21. Autophagy Accompanies Inflammasome Activation to Moderate Inflammation by Eliminating Active Inflammasomes
- Author
-
John H. Kehrl, Chong-Shan Shi, and Neel R. Nabar
- Subjects
0301 basic medicine ,Innate immune system ,Autophagy ,Cellular homeostasis ,Inflammation ,Inflammasome ,Biology ,Systemic inflammation ,Cell biology ,03 medical and health sciences ,AIM2 ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Lysosome ,medicine ,medicine.symptom ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Inflammation is an important physiological response to noxious stimuli, but unchecked inflammation is pathophysiological and can result in tissue destruction and autoimmune disease. Inflammasomes are large multimeric signaling complexes of the innate immune system involved in the proteolytic cleavage and activation of interleukin-1 beta (IL-1β) and IL-18. Inflammasome signaling is a key early step in generating the inflammatory response as IL-1β is a critical cytokine in mediating systemic inflammation and has a variety of downstream effects. Aberrant inflammasome activation is the basis of many human autoinflammatory diseases, thus delineation of feedback loops regulating inflammasome signaling is of great importance to understanding autoinflammatory conditions. Autophagy is a conserved degradation pathway that delivers damaged organelles and aged protein complexes to the lysosome for destruction. It evolved both as a cellular recycling system and as a quality control system to ensure cellular homeostasis. This chapter covers the dynamic interplay between inflammasome activation and autophagy induction, with a specific focus on the cellular and molecular mechanisms by which autophagy feedback inhibits inflammasome signaling.
- Published
- 2017
22. Contents Vol. 90, 2012
- Author
-
Keisuke Ishizawa, Jung Sook Suh, Maria Frosini, Masaki Imanishi, Sarah J. Mitchell, Kai Kappert, Linyong Xu, Georg Dechant, Sui-Lin Mo, Heiko Funke-Kaiser, Piero Tanganelli, Koichiro Tsuchiya, M. Zeitlinger, Ludo Willems, Josef Donnerer, Jae-Wook Oh, Z. Erdogan, A. Burian, Ingrid Liebmann, Ignacio Valencia-Hernández, Bosheng Huang, Christian Humpel, Min-Ji Song, Constanze M. Barwitz, Licht Miyamoto, Giampietro Sgaragli, José Carlos Villegas-Bedolla, Hyung-Sik Kang, Tomoyuki Nishizaki, Alessandra Larini, Shu-Feng Zhou, Jin-Jun Zhang, Geert Meyfroidt, Kisung Ko, Kerstin Seidel, Daniel Godínez-Hernández, Hyun Soo Kwak, Lorenzo Ricci, Luisa Lucas, Victoria C. Cogger, Héctor Urquiza-Marín, Yasumasa Ikeda, Yoshitaka Kihira, Gerald Zernig, Shuhei Tomita, Shoko Fujii, Sarah N. Hilmer, Ming Wei, Haeng-A. Kang, Geert Maleux, Yuling Chen, Rafael de Cabo, Min Park, Beatrice Gorelli, Lai-Bao Sun, Kai K. Kummer, Takeshi Kanno, Xue-Nong Zou, Chris Verslype, Sarah Bernhard, Ki-Mo Lee, Blanca Nateras-Marín, José Antonio Reyes-Ramírez, Sabrina Klare, Toshiaki Tamaki, Akinobu Gotoh, Brett Jones, Janine M. Prast, Hwa-Youn Lee, Eva Schrezenmeier, Christian Böhm, Wan Kyunn Whang, Takumi Sakurada, Shuichi Hamano, Jong Mi Lee, Yuki Izawa-Ishizawa, Isabel Spriet, Aniko Huizer-Pajkos, Chung Hyo Kim, David G. Le Couteur, Massimo Valoti, Sebastian Kirsch, C. Jandrisits, Petra Goldin-Lang, Andrew J. McLachlan, Druck Reinhardt Druck Basel, Uy Dong Sohn, Thao Thanh Nguyen, Sun Young Park, Xian-Guo Liu, Lijun Cao, Neel R. Nabar, Melanie Kroh, Qiu-Lan He, Werner Skuballa, Hisao Nagaya, Frank S. Zollmann, Lixiang Wu, Hironori Taira, Thomas Unger, and Kristin Schmerbach
- Subjects
Pharmacology ,General Medicine - Published
- 2012
23. Modification of Rat Model of Sciatica Induced by Lumber Disc Herniation and the Anti-Inflammatory Effect of Osthole Given by Epidural Catheterization
- Author
-
Xian-Guo Liu, Qiu-Lan He, Shu-Feng Zhou, Ming Wei, Xuenong Zou, Jin-Jun Zhang, Lai-Bao Sun, Yuling Chen, Neel R. Nabar, and Sui-Lin Mo
- Subjects
Male ,medicine.drug_class ,Anti-Inflammatory Agents ,Injections, Epidural ,Pain ,Lumbar vertebrae ,Anti-inflammatory ,Catheterization ,Rats, Sprague-Dawley ,Sciatica ,Coumarins ,Fibrosis ,medicine ,Back pain ,Animals ,Pharmacology ,Lumbar Vertebrae ,biology ,business.industry ,General Medicine ,medicine.disease ,Epidural space ,Rats ,Nitric oxide synthase ,Disease Models, Animal ,medicine.anatomical_structure ,Cyclooxygenase 2 ,Anesthesia ,Hyperalgesia ,biology.protein ,Nitric Oxide Synthase ,medicine.symptom ,business ,Intervertebral Disc Displacement - Abstract
One of the most treatable causes of lower back pain and associated sciatica is lumbar disc herniation (LDH), which is characterized by rupture of the hard outer wall (annulus fibrosis) in a lumbar intervertebral disc. In the current study, we aimed to: (1) develop and characterize a rat model of sciatica induced by LDH, while introducing a novel method of epidural catheterization; (2) use this model to evaluate the effect of osthole on pain due to LDH, and (3) gain insight into the mechanisms through which osthole affects sciatica induced by LDH. The results indicate that our newly developed rat model maintained mechanical allodynia for 28 days without reduction. Moreover, cyclooxygenase-2 (COX-2) and nitric oxide synthase (NOS) were overexpressed in the associated inflammatory response, which is consistent with clinical manifestations of the disease. We then used this model to study the effect and mechanisms through which osthole affected pain due to LDH. Our study suggests that osthole is capable of reversing hyperalgesia due to LDH, potentially through modulation of activity of COX-2 and NOS, two important proteins for the exacerbation of pain due to LDH. Finally, a molecular modeling simulation showed that osthole has unique binding capabilities to both NOS and COX-2. As the model-induced mechanical hyperalgesia response was consistent, and the position of the catheter tip and the extension/spreading of the drug in the epidural space were reliable, this study developed an improved model to study remedies for sciatic pain. Moreover, our studies demonstrate that osthole may be a feasible treatment for the reduction of pain due to hyperalgesia.
- Published
- 2012
24. The potential therapeutic effects of THC on Alzheimer's disease
- Author
-
Neel R. Nabar, Kyle Sutherland, Xiaoyang Lin, Jianfeng Cai, Yaqiong Li, Ge Bai, Jonathan Mayl, Chuanhai Cao, and Hui Liu
- Subjects
Cannabinoid receptor ,medicine.medical_treatment ,Cell Respiration ,Enzyme-Linked Immunosorbent Assay ,tau Proteins ,Pharmacology ,Transfection ,Amyloid beta-Protein Precursor ,Glycogen Synthase Kinase 3 ,Mice ,Neuroblastoma ,Cell Line, Tumor ,mental disorders ,Delta-9-tetrahydrocannabinol ,medicine ,Cannabinoid receptor type 2 ,Animals ,Humans ,MTT assay ,Dronabinol ,Phosphorylation ,Glycogen synthase ,Cannabinoid Receptor Agonists ,Amyloid beta-Peptides ,Glycogen Synthase Kinase 3 beta ,biology ,Dose-Response Relationship, Drug ,Chemistry ,organic chemicals ,General Neuroscience ,Neurodegeneration ,General Medicine ,medicine.disease ,Mitochondria ,Psychiatry and Mental health ,Clinical Psychology ,Toxicity ,Mutation ,biology.protein ,Cannabinoid ,Geriatrics and Gerontology ,Signal Transduction - Abstract
The purpose of this study was to investigate the potential therapeutic qualities of Δ9-tetrahydrocannabinol (THC) with respect to slowing or halting the hallmark characteristics of Alzheimer's disease. N2a-variant amyloid-β protein precursor (AβPP) cells were incubated with THC and assayed for amyloid-β (Aβ) levels at the 6-, 24-, and 48-hour time marks. THC was also tested for synergy with caffeine, in respect to the reduction of the Aβ level in N2a/AβPPswe cells. THC was also tested to determine if multiple treatments were beneficial. The MTT assay was performed to test the toxicity of THC. Thioflavin T assays and western blots were performed to test the direct anti-Aβ aggregation significance of THC. Lastly, THC was tested to determine its effects on glycogen synthase kinase-3β (GSK-3β) and related signaling pathways. From the results, we have discovered THC to be effective at lowering Aβ levels in N2a/AβPPswe cells at extremely low concentrations in a dose-dependent manner. However, no additive effect was found by combining caffeine and THC together. We did discover that THC directly interacts with Aβ peptide, thereby inhibiting aggregation. Furthermore, THC was effective at lowering both total GSK-3β levels and phosphorylated GSK-3β in a dose-dependent manner at low concentrations. At the treatment concentrations, no toxicity was observed and the CB1 receptor was not significantly upregulated. Additionally, low doses of THC can enhance mitochondria function and does not inhibit melatonin's enhancement of mitochondria function. These sets of data strongly suggest that THC could be a potential therapeutic treatment option for Alzheimer's disease through multiple functions and pathways.
- Published
- 2014
25. Cell therapy: a safe and efficacious therapeutic treatment for Alzheimer's disease in APP+PS1 mice
- Author
-
Yaqiong Li, Jonathan Mayl, Jinhuan Wang, Shu-Feng Zhou, Chuanhai Cao, Neel R. Nabar, Li Wang, Ge Bai, Fang Yuan, Xiaoyang Lin, and Jianfeng Cai
- Subjects
Mouse ,Science ,medicine.medical_treatment ,Immune Cells ,Molecular Sequence Data ,Immunology ,Cell- and Tissue-Based Therapy ,Antigen-Presenting Cells ,Inflammation ,Enzyme-Linked Immunosorbent Assay ,Cell therapy ,Amyloid beta-Protein Precursor ,Mice ,Model Organisms ,Alzheimer Disease ,Neurobiology of Disease and Regeneration ,medicine ,Presenilin-1 ,Animals ,Amino Acid Sequence ,Cognitive decline ,Maze Learning ,Biology ,Multidisciplinary ,biology ,Behavior, Animal ,business.industry ,Antibody titer ,Neurodegenerative Diseases ,Immunotherapy ,Animal Models ,medicine.disease ,Disease Models, Animal ,Neurology ,Immune System ,biology.protein ,Cytokines ,Medicine ,Dementia ,Alzheimer's disease ,Antibody ,medicine.symptom ,business ,Ex vivo ,Research Article ,Neuroscience - Abstract
Previously, our lab was the first to report the use of antigen-sensitized dendritic cells as a vaccine against Alzheimer's disease (AD). In preparation of this vaccine, we sensitized the isolated dendritic cells ex vivo with Aβ peptide, and administered these sensitized dendritic cells as a therapeutic agent. This form of cell therapy has had success in preventing and/or slowing the rate of cognitive decline when administered prior to the appearance of Aβ plaques in PDAPP mice, but has not been tested in 2 × Tg models. Herein, we test the efficacy and safety of this vaccine in halting and reversing Alzheimer's pathology in 9-month-old APP + PS1 mice. The results showed that administration of this vaccine elicits a long-lasting antibody titer, which correlated well with a reduction of Aβ burden upon histological analysis. Cognitive function in transgenic responders to the vaccine was rescued to levels similar to those found in non-transgenic mice, indicating that the vaccine is capable of providing therapeutic benefit in APP+PS1 mice when administered after the onset of AD pathology. The vaccine also shows indications of circumventing past safety problems observed in AD immunotherapy, as Th1 pro-inflammatory cytokines were not elevated after long-term vaccine administration. Moreover, microhemorrhaging and T-cell infiltration into the brain are not observed in any of the treated subjects. All in all, this vaccine has many advantages over contemporary vaccines against Alzheimer's disease, and may lead to a viable treatment for the disease in the future.
- Published
- 2012
26. Efficacy of a therapeutic vaccine using mutated β-amyloid sensitized dendritic cells in Alzheimer's mice
- Author
-
Chuanhai Cao, Neel R. Nabar, Ge Bai, Zhongqiu Luo, Xiaoyang Lin, Jinhuan Wang, Jianfeng Cai, Shu-Feng Zhou, and Jialin Li
- Subjects
Genetically modified mouse ,Male ,Alzheimer Vaccines ,Amyloid beta ,medicine.medical_treatment ,Immunology ,Molecular Sequence Data ,Neuroscience (miscellaneous) ,Inflammation ,Mice, Transgenic ,Mice ,Immune system ,Alzheimer Disease ,medicine ,Vaccines, DNA ,Immunology and Allergy ,Animals ,Amino Acid Sequence ,Pharmacology ,Amyloid beta-Peptides ,biology ,business.industry ,Antibody titer ,Immunotherapy ,Dendritic cell ,Dendritic Cells ,Peptide Fragments ,Mice, Inbred C57BL ,Titer ,Treatment Outcome ,Mutation ,biology.protein ,Female ,medicine.symptom ,business - Abstract
Despite FDA suspension of Elan’s AN-1792 amyloid beta (Aβ) vaccine in phase IIb clinical trials, the implications of this study are the guiding principles for contemporary anti-Aβ immunotherapy against Alzheimer’s disease (AD). AN-1792 showed promising results with regards to Aβ clearance and cognitive function improvement, but also exhibited an increased risk of Th1 mediated meningoencephalitis. As such, vaccine development has continued with an emphasis on eliciting a notable anti-Aβ antibody titer, while avoiding the unwanted Th1 pro-inflammatory response. Previously, we published the first report of an Aβ sensitized dendritic cell vaccine as a therapeutic treatment for AD in BALB/c mice. Our vaccine elicited an anti-Aβ titer, with indications that a Th1 response was not present. This study is the first to investigate the efficacy and safety of our dendritic cell vaccine for the prevention of AD in transgenic mouse models (PDAPP) for AD. We also used Immunohistochemistry to characterize the involvement of LXR, ABCA1, and CD45 in order to gain insight into the potential mechanisms through which this vaccine may provide benefit. The results indicate that (1) the use of mutant Aβ1-42 sensitized dendritic cell vaccine results in durable antibody production, (2) the vaccine provides significant benefits with regards to cognitive function without the global (Th1) inflammation seen in prior Aβ vaccines, (3) histological studies showed an overall decrease in Aβ burden, with an increase in LXR, ABCA1, and CD45, and (4) the beneficial results of our DC vaccine may be due to the LXR/ABCA1 pathway. In the future, mutant Aβ sensitized dendritic cell vaccines could be an efficacious and safe method for the prevention or treatment of AD that circumvents problems associated with traditional anti-Aβ vaccines.
- Published
- 2012
27. Studies on the removal of Lissamine Green B from clays and soil in comparison with contemporary approaches
- Author
-
Dean F. Martin and Neel R. Nabar
- Subjects
chemistry.chemical_classification ,Environmental Engineering ,Environmental remediation ,Iron ,Extraction (chemistry) ,General Medicine ,Human decontamination ,Hydrogen Peroxide ,Phenanthrene ,chemistry.chemical_compound ,Soil ,Montmorillonite ,Column chromatography ,Hydrocarbon ,Lissamine Green Dyes ,chemistry ,Reagent ,Environmental chemistry ,Bentonite ,Electrochemistry ,Clay ,Soil Pollutants ,Aluminum Silicates ,Kaolin ,Nuclear chemistry - Abstract
A combination of Fenton's reagent with electrochemistry has been demonstrated to be a efficient method for removing a dye (Lissamine Green B) from clays (kaolin, montmorillonite) and soil. The two-step approach described here involved quantitative extraction with hot water, followed by quantitative removal of the Lissamine Green dye by column chromatography using Octolig®. The advantage of this procedure is success without the need for Fenton reagents or electricity. A disadvantage is the process would not work with polycyclic hydrocarbons such as phenanthrene, though the electro-Fenton degradation does.
- Published
- 2012
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.