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Huang H, Hou J, Liao Y, Wei F, Xing B. Polyethylene microplastics impede the innate immune response by disrupting the extracellular matrix and signaling transduction. iScience 2023; 26:107390. [PMID: 37554443 PMCID: PMC10405319 DOI: 10.1016/j.isci.2023.107390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 06/01/2023] [Accepted: 07/10/2023] [Indexed: 08/10/2023] Open
Abstract
Microplastics (MPs) can accumulate in animal organs. Numerous studies have linked MPs with immune system. However, the impact of MPs on immune response remains unclear. This study examined the innate immune response of mice exposed to 5 μm MPs. In the lipopolysaccharide challenge, mice treated with MPs exhibited lower levels of serum immune factors and activated immune cells. MPs disrupted immune-related receptors and cause dysfunction in cell signal transduction within the liver and spleen. Proteomic analysis revealed that MPs impede the activation of serum immune-related signals. In addition, the tissue section imaging exhibited a significant enrichment of MPs in the extracellular matrix (ECM), consistent with the ECM dysfunction and immune receptor suppression. Therefore, our data suggest excessive MPs accumulation in ECM inhibits cell signaling pathways, thereby suppressing the activation of immune responses. We propose the biotoxicity of MPs is partly through the MP disruption of ECM (MPDEM).
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Affiliation(s)
- Haipeng Huang
- School of Life Science, Tsinghua University, Beijing 100084, China
- Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing 100871, China
| | - Jiaqi Hou
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yilie Liao
- School of Life Science, Tsinghua University, Beijing 100084, China
| | - Fangchao Wei
- School of Life Science, Tsinghua University, Beijing 100084, China
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27708, USA
| | - Baoshan Xing
- Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003, USA
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2
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Li S, Keenan JI, Shaw IC, Frizelle FA. Could Microplastics Be a Driver for Early Onset Colorectal Cancer? Cancers (Basel) 2023; 15:3323. [PMID: 37444433 DOI: 10.3390/cancers15133323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 06/12/2023] [Accepted: 06/18/2023] [Indexed: 07/15/2023] Open
Abstract
Introduction: The incidence of colorectal cancer in those under 50 years of age (early onset colorectal cancer (EOCRC)) is increasing throughout the world. This has predominantly been an increase in distal colonic and rectal cancers, which are biologically similar to late onset colorectal cancer (LOCRC) but with higher rates of mucinous or signet ring histology, or poorly differentiated cancers. The epidemiology of this change suggests that it is a cohort effect since 1960, and is most likely driven by an environmental cause. We explore the possible role of microplastics as a driver for this change. Review: The development of sporadic colorectal cancer is likely facilitated by the interaction of gut bacteria and the intestinal wall. Normally, a complex layer of luminal mucus provides colonocytes with a level of protection from the effects of these bacteria and their toxins. Plastics were first developed in the early 1900s. After 1945 they became more widely used, with a resultant dramatic increase in plastic pollution and their breakdown to microplastics. Microplastics (MPs) are consumed by humans from an early age and in increasingly large quantities. As MPs pass through the gastrointestinal tract they interact with the normal physiological mechanism of the body, particularly in the colon and rectum, where they may interact with the protective colonic mucus layer. We describe several possible mechanisms of how microplastics may disrupt this mucus layer, thus reducing its protective effect and increasing the likelihood of colorectal cancer. Conclusions: The epidemiology of increase in EOCRC suggests an environmental driver. This increase in EOCRC matches the time sequence in which we could expect to see an effect of rapid increase of MPs in the environment and, as such, we have explored possible mechanisms for this effect. We suggest that it is possible that the MPs damage the barrier integrity of the colonic mucus layer, thus reducing its protective effect. MPs in CRC pathogenesis warrants further investigation. Future directions: Further clarification needs to be sought regarding the interaction between MPs, gut microbiota and the mucus layer. This will need to be modelled in long-term animal studies to better understand how chronic consumption of environmentally-acquired MPs may contribute to an increased risk of colorectal carcinogenesis.
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Affiliation(s)
- Shelley Li
- Department of Surgery, University of Otago Christchurch, Christchurch 8011, New Zealand
| | - Jacqueline I Keenan
- Department of Surgery, University of Otago Christchurch, Christchurch 8011, New Zealand
| | - Ian C Shaw
- School of Physical & Chemical Sciences, University of Canterbury, Christchurch 8041, New Zealand
| | - Frank A Frizelle
- Department of Surgery, University of Otago Christchurch, Christchurch 8011, New Zealand
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3
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Gruber ES, Stadlbauer V, Pichler V, Resch-Fauster K, Todorovic A, Meisel TC, Trawoeger S, Hollóczki O, Turner SD, Wadsak W, Vethaak AD, Kenner L. To Waste or Not to Waste: Questioning Potential Health Risks of Micro- and Nanoplastics with a Focus on Their Ingestion and Potential Carcinogenicity. EXPOSURE AND HEALTH 2022; 15:33-51. [PMID: 36873245 PMCID: PMC9971145 DOI: 10.1007/s12403-022-00470-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 12/30/2021] [Accepted: 02/11/2022] [Indexed: 05/27/2023]
Abstract
Micro- and nanoplastics (MNPs) are recognized as emerging contaminants, especially in food, with unknown health significance. MNPs passing through the gastrointestinal tract have been brought in context with disruption of the gut microbiome. Several molecular mechanisms have been described to facilitate tissue uptake of MNPs, which then are involved in local inflammatory and immune responses. Furthermore, MNPs can act as potential transporters ("vectors") of contaminants and as chemosensitizers for toxic substances ("Trojan Horse effect"). In this review, we summarize current multidisciplinary knowledge of ingested MNPs and their potential adverse health effects. We discuss new insights into analytical and molecular modeling tools to help us better understand the local deposition and uptake of MNPs that might drive carcinogenic signaling. We present bioethical insights to basically re-consider the "culture of consumerism." Finally, we map out prominent research questions in accordance with the Sustainable Development Goals of the United Nations.
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Affiliation(s)
- Elisabeth S. Gruber
- Division of Visceral Surgery, Department of General Surgery, Medical University of Vienna, Vienna, Austria
| | - Vanessa Stadlbauer
- Department of Internal Medicine, Division of Gastroenterology and Hepatology, Medical University of Graz, Graz, Austria
- Center for Biomarker Research in Medicine (CBmed), Graz, Austria
| | - Verena Pichler
- Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | | | - Andrea Todorovic
- Materials Science and Testing of Polymers, Montanuniversitaet Leoben, Styria, Austria
| | - Thomas C. Meisel
- General and Analytical Chemistry, Montanuniversitaet Leoben, Styria, Austria
| | - Sibylle Trawoeger
- Division of Systematic Theology and its Didactics, Faculty of Catholic Theology, University of Wuerzburg, Wuerzburg, Germany
| | - Oldamur Hollóczki
- Mulliken Center for Theoretical Chemistry, University of Bonn, Bonn, Germany
| | - Suzanne D. Turner
- Department of Pathology, University of Cambridge, Cambridge, CB2 1QP UK
- Central European Institute of Technology, Masaryk University, 602 00 Brno, Czech Republic
| | - Wolfgang Wadsak
- Center for Biomarker Research in Medicine (CBmed), Graz, Austria
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
| | - A. Dick Vethaak
- Department of Environment and Health, Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Unit of Marine and Coastal Systems, Deltares, P.O. Box 177, 2600 MH Delft, Netherlands
| | - Lukas Kenner
- Center for Biomarker Research in Medicine (CBmed), Graz, Austria
- Christian Doppler Laboratory for Applied Metabolomics, Medical University of Vienna, Vienna, Austria
- Division of Experimental and Laboratory Animal Pathology, Department of Pathology Medical, University of Vienna, Vienna, Austria
- Unit of Laboratory Animal Pathology, University of Veterinary Medicine Vienna, Vienna, Austria
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4
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Keinänen O, Dayts EJ, Rodriguez C, Sarrett SM, Brennan JM, Sarparanta M, Zeglis BM. Harnessing PET to track micro- and nanoplastics in vivo. Sci Rep 2021; 11:11463. [PMID: 34075133 PMCID: PMC8169765 DOI: 10.1038/s41598-021-90929-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/19/2021] [Indexed: 02/04/2023] Open
Abstract
The proliferation of plastics in the environment continues at an alarming rate. Plastic particles have been found to be persistent and ubiquitous pollutants in a variety of environments, including sea water, fresh water, soil, and air. In light of this phenomenon, the scientific and medical communities have become increasingly wary of the dangers posed to human health by chronic exposure to microplastics (< 5 mm diameter) and nanoplastics (< 100 nm diameter). A critical component of the study of the health effects of these pollutants is the accurate determination of their pharmacokinetic behavior in vivo. Herein, we report the first use of molecular imaging to track polystyrene (PS) micro- and nanoplastic particles in mammals. To this end, we have modified PS particles of several sizes-diameters of 20 nm, 220 nm, 1 µm, and 6 µm-with the chelator desferrioxamine (DFO) and radiolabeled these DFO-bearing particles with the positron-emitting radiometal zirconium-89 (89Zr; t1/2 ~ 3.3 d). Subsequently, positron emission tomography (PET) was used to visualize the biodistribution of these radioplastics in C57BL/6J mice at 6, 12, 24, and 48 h after ingestion. The imaging data reveal that the majority of the radioplastics remain in the gastrointestinal tract and are eliminated through the feces by 48 h post-ingestion, a result reinforced by acute biodistribution studies. Ultimately, this work suggests that nuclear imaging-and PET in particular-can be a sensitive and effective tool in the urgent and rapidly growing effort to study the in vivo behavior and potential toxicity of micro- and nanoplastics.
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Affiliation(s)
- Outi Keinänen
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA ,grid.7737.40000 0004 0410 2071Department of Chemistry, University of Helsinki, Helsinki, Finland ,grid.51462.340000 0001 2171 9952Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY USA
| | - Eric J. Dayts
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA
| | - Cindy Rodriguez
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA ,grid.253482.a0000 0001 0170 7903Ph.D. Program in Chemistry, Graduate Center of the City University of New York, New York, NY USA
| | - Samantha M. Sarrett
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA ,grid.253482.a0000 0001 0170 7903Ph.D. Program in Biochemistry, Graduate Center of the City University of New York, New York, NY USA
| | - James M. Brennan
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA
| | - Mirkka Sarparanta
- grid.7737.40000 0004 0410 2071Department of Chemistry, University of Helsinki, Helsinki, Finland
| | - Brian M. Zeglis
- grid.212340.60000000122985718Department of Chemistry, Hunter College, City University of New York, 413 East 69th Street, New York, NY 10021 USA ,grid.51462.340000 0001 2171 9952Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY USA ,grid.253482.a0000 0001 0170 7903Ph.D. Program in Chemistry, Graduate Center of the City University of New York, New York, NY USA ,grid.253482.a0000 0001 0170 7903Ph.D. Program in Biochemistry, Graduate Center of the City University of New York, New York, NY USA ,grid.5386.8000000041936877XDepartment of Radiology, Weill Cornell Medical College, New York, NY USA
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5
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Mortensen NP, Johnson LM, Grieger KD, Ambroso JL, Fennell TR. Biological interactions between nanomaterials and placental development and function following oral exposure. Reprod Toxicol 2019; 90:150-165. [PMID: 31476381 DOI: 10.1016/j.reprotox.2019.08.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 08/27/2019] [Accepted: 08/29/2019] [Indexed: 12/18/2022]
Abstract
We summarize the literature involving the deposition of nanomaterials within the placenta following oral exposure and the biological interactions between nanomaterials and placental development and function. The review focuses on the oral exposure of metal and metal oxide engineered nanomaterials (ENMs), carbon-based ENMs, and nanoplastics in animal models, with a minor discussion of intravenous injections. Although the literature suggests that the placenta is an efficient barrier in preventing nanomaterials from reaching the fetus, nanomaterials that accumulate in the placenta may interfere with its development and function. Furthermore, some studies have demonstrated a decrease in placental weight and association with adverse fetal health outcomes following oral exposure to nanomaterials. Since nanomaterials are increasingly used in food, food packaging, and have been discovered in drinking water, the risk for adverse impacts on placental development and functions, with secondary effects on embryo-fetal development, following unintentional maternal ingestion of nanomaterials requires further investigation.
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Affiliation(s)
- Ninell P Mortensen
- Discovery Sciences, RTI International, 3040 Cornwallis Rd, RTP, NC, 27709, USA.
| | - Leah M Johnson
- Engineered Systems, RTI International, 3040 Cornwallis Rd, RTP, NC, 27709, USA
| | - Khara D Grieger
- Health and Environmental Risk Analysis Program, RTI International, 3040 Cornwallis Rd, RTP, NC, 27709, USA; Genetic Engineering and Society Center, North Carolina State University, 1070 Partners Way, Raleigh, NC, 27695, USA
| | - Jeffrey L Ambroso
- Center for Global Health, RTI International, 3040 Cornwallis Rd, RTP, NC, 27709, USA
| | - Timothy R Fennell
- Discovery Sciences, RTI International, 3040 Cornwallis Rd, RTP, NC, 27709, USA
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6
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Thanos CG, Yip KP, Mathiowitz E. Intestinal Uptake of Polymer Microspheres in the Rabbit Studied with Confocal Microscopy. J BIOACT COMPAT POL 2016. [DOI: 10.1177/0883911504045275] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study characterizes the ability of several polymer formulations to penetrate the absorptive epithelium and lymphoid-associated tissue of the gastrointestinal tract. Using phase inversion nano encapsulation and solvent diffusion, formulations with variable size ranges consisting of either poly(fumaric-co-sebacic)anhydride, poly(lactide-co-glycolide), polystyrene, or polycaprolactone were fabricated and administered to an isolated loop in the small intestine of rabbits. Particles were loaded with a fluorescent dye for detection. Following a period of incubation, animals were sacrificed and the tissue was explanted and processed for histology. Confocal laser scanning microscopy (CLSM) was used to track the microspheres and two separate emission detectors were used to isolate the dye from background. Particles that possess bioadhesiveness in the micron size range could be localized to the absorptive epithelium while larger particles and formulations with low bioadhesiveness failed to penetrate enterocytes and were taken up preferentially in the Peyer’s patches. This work demonstrates that the surface chemistry of oral formulations can ultimately determine the fate and can aid in designing delivery vehicles for a variety of therapeutics currently plagued with poor oral bioavailability.
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7
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Cheng L, Xu PH, Shen BD, Shen G, Li JJ, Qiu L, Liu CY, Yuan HL, Han J. Improve bile duct-targeted drug delivery and therapeutic efficacy for cholangiocarcinoma by cucurbitacin B loaded phospholipid complex modified with berberine hydrochloride. Int J Pharm 2015; 489:148-57. [PMID: 25882012 DOI: 10.1016/j.ijpharm.2015.04.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 04/10/2015] [Indexed: 02/07/2023]
Abstract
In present study, a novel phospholipid complex loaded cucurbitacin B modified with berberine hydrochloride (CUB-PLC-BER) was prepared by a simple solvent evaporation method with the aim of improving bile duct-targeted drug delivery and therapeutic efficacy for cholangiocarcinoma (CC). The complex's physicochemical properties were systemically investigated in terms of scanning electron microscopy (SEM), x-ray diffraction (XRD) and infrared absorption spectroscopy (IR). In vivo and in vitro antitumor studies, CUB-PLC-BER and the unmodified cucurbitacin B-phospholipid complex (CUB-PLC) presented stronger antitumor efficacy against human cholangiocarcinoma cells (QBC939 cells) than free cucurbitacin B (CUB), while phospholipids (PL) itself had no significant toxicity. Besides that, CUB-PLC showed the advantage over the free CUB and CUB-PLC-BER with regard to the inhibition of tumor growth in vivo antitumor study. Failure to establish the orthotopic CC model, the study attempted to measure the level of CUB in plasma and in bile to explore bile duct-targeted effect indirectly. In the pharmacokinetics study in rats, the average values of Cmax and AUC0-8h of CUB-PLC-BER group in rat bile were higher than those of CUB-PLC, while an opposite result was found in plasma. Meanwhile, the Cmax, AUC0-8h and AUC0-24h of CUB were the least both in plasma and in bile. The results indicated that the CUB-PLC-BER tended to provide a high and prolonged drug concentration to bile duct, and PL played a central role in internalizing CUB into cells to improve the water insoluble drug's permeability, which was of great benefit to enhance the bioavailability of CUB and improve therapeutic efficacy of CC. These results elucidated the potential of CUB-PLC-BER as drug delivery system for improving bile duct-targeted and therapeutic efficacy for CC.
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Affiliation(s)
- Ling Cheng
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China; Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ping-hua Xu
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China
| | - Bao-de Shen
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China
| | - Gang Shen
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China; Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Juan-juan Li
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China; Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Ling Qiu
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China; Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Chao-yong Liu
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China; Pharmacy College, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Hai-long Yuan
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China.
| | - Jin Han
- 302 Hospital of PLA&PLA Institute of Chinese Materia Medica, Beijing 100039, China.
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8
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Zou P, Helson L, Maitra A, Stern ST, McNeil SE. Polymeric curcumin nanoparticle pharmacokinetics and metabolism in bile duct cannulated rats. Mol Pharm 2013; 10:1977-87. [PMID: 23534919 PMCID: PMC3683459 DOI: 10.1021/mp4000019] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The objective of this study was to compare the pharmacokinetics and metabolism of polymeric nanoparticle-encapsulated (nanocurcumin) and solvent-solubilized curcumin formulations in Sprague-Dawley (SD) rats. Nanocurcumin is currently under development for cancer therapy. Since free, unencapsulated curcumin is rapidly metabolized and excreted in rats, upon intravenous (i.v.) administration of nanocurcumin only nanoparticle-encapsulated curcumin can be detected in plasma samples. Hence, the second objective of this study was to utilize the metabolic instability of curcumin to assess in vivo drug release from nanocurcumin. Nanocurcumin and solvent-solubilized curcumin were administered at 10 mg curcumin/kg by jugular vein to bile duct-cannulated male SD rats (n = 5). Nanocurcumin increased the plasma Cmax of curcumin 1749 fold relative to the solvent-solubilized curcumin. Nanocurcumin also increased the relative abundance of curcumin and glucuronides in bile but did not dramatically alter urine and tissue metabolite profiles. The observed increase in biliary and urinary excretion of both curcumin and metabolites for the nanocurcumin formulation suggested a rapid "burst" release of curcumin. Although the burst release observed in this study is a limitation for targeted tumor delivery, nanocurcumin still exhibits major advantages over solvent-solubilized curcumin, as the nanoformulation does not result in the lung accumulation observed for the solvent-solubilized curcumin and increases overall systemic curcumin exposure. Additionally, the remaining encapsulated curcumin fraction following burst release is available for tumor delivery via the enhanced permeation and retention effect commonly observed for nanoparticle formulations.
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Affiliation(s)
- Peng Zou
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD 21702
| | - Lawrence Helson
- Sign Path Pharma, Inc, 1375 California Road, Quakertown, PA 18951
| | - Anirban Maitra
- Johns Hopkins University School of Medicine, 1550 Orleans Street, Baltimore, MD 21231
| | - Stephan T. Stern
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD 21702
| | - Scott E. McNeil
- Nanotechnology Characterization Laboratory, Advanced Technology Program, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD 21702
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9
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In vivo biodistribution and toxicology of functionalized nano-graphene oxide in mice after oral and intraperitoneal administration. Biomaterials 2013; 34:2787-95. [DOI: 10.1016/j.biomaterials.2013.01.001] [Citation(s) in RCA: 322] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 01/01/2013] [Indexed: 12/14/2022]
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10
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Garrett NL, Lalatsa A, Uchegbu I, Schätzlein A, Moger J. Exploring uptake mechanisms of oral nanomedicines using multimodal nonlinear optical microscopy. JOURNAL OF BIOPHOTONICS 2012; 5:458-68. [PMID: 22389316 DOI: 10.1002/jbio.201200006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 02/11/2012] [Accepted: 02/12/2012] [Indexed: 05/23/2023]
Abstract
Advances in pharmaceutical nanotechnology have yielded ever increasingly sophisticated nanoparticles for medicine delivery. When administered via oral, intravenous, ocular and transcutaneous delivery routes, these nanoparticles can elicit enhanced drug performance. In spite of this, little is known about the mechanistic processes underlying interactions between nanoparticles and tissues, or how these correlate with improved pharmaceutical effects. These mechanisms must be fully understood before nanomedicines can be rationally engineered to optimise their performance. Methods to directly visualise these particulates within tissue samples have traditionally involved imaging modalities requiring covalent labelling of fluorescent or radioisotope contrast agents. We present CARS, second harmonic generation and two photon fluorescence microscopy combined as a multi-modal label-free method for pinpointing polymeric nanoparticles within the stomach, intestine, gall bladder and liver. We demonstrate for the first time that orally administered chitosan nanoparticles follow a recirculation pathway from the GI tract via enterocytes, to the liver hepatocytes and intercellular spaces and then to the gall bladder, before being re-released into the gut together with bile.
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11
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Aksungur P, Demirbilek M, Denkbaş EB, Vandervoort J, Ludwig A, Ünlü N. Development and characterization of Cyclosporine A loaded nanoparticles for ocular drug delivery: Cellular toxicity, uptake, and kinetic studies. J Control Release 2011; 151:286-94. [DOI: 10.1016/j.jconrel.2011.01.010] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Revised: 12/30/2010] [Accepted: 01/09/2011] [Indexed: 10/18/2022]
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12
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Yokel RA, MacPhail RC. Engineered nanomaterials: exposures, hazards, and risk prevention. J Occup Med Toxicol 2011; 6:7. [PMID: 21418643 PMCID: PMC3071337 DOI: 10.1186/1745-6673-6-7] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Accepted: 03/21/2011] [Indexed: 01/15/2023] Open
Abstract
Nanotechnology presents the possibility of revolutionizing many aspects of our lives. People in many settings (academic, small and large industrial, and the general public in industrialized nations) are either developing or using engineered nanomaterials (ENMs) or ENM-containing products. However, our understanding of the occupational, health and safety aspects of ENMs is still in its formative stage. A survey of the literature indicates the available information is incomplete, many of the early findings have not been independently verified, and some may have been over-interpreted. This review describes ENMs briefly, their application, the ENM workforce, the major routes of human exposure, some examples of uptake and adverse effects, what little has been reported on occupational exposure assessment, and approaches to minimize exposure and health hazards. These latter approaches include engineering controls such as fume hoods and personal protective equipment. Results showing the effectiveness - or lack thereof - of some of these controls are also included. This review is presented in the context of the Risk Assessment/Risk Management framework, as a paradigm to systematically work through issues regarding human health hazards of ENMs. Examples are discussed of current knowledge of nanoscale materials for each component of the Risk Assessment/Risk Management framework. Given the notable lack of information, current recommendations to minimize exposure and hazards are largely based on common sense, knowledge by analogy to ultrafine material toxicity, and general health and safety recommendations. This review may serve as an overview for health and safety personnel, management, and ENM workers to establish and maintain a safe work environment. Small start-up companies and research institutions with limited personnel or expertise in nanotechnology health and safety issues may find this review particularly useful.
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Affiliation(s)
- Robert A Yokel
- Department of Pharmaceutical Sciences, College of Pharmacy and Graduate Center for Toxicology, University of Kentucky, Lexington, KY, 40536-0082, USA
| | - Robert C MacPhail
- Toxicity Assessment Division, National Health and Environmental Effects Research Laboratory, U.S. Environmental Protection Agency, Research Triangle Park NC, 27711, USA
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13
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Schleh C, Semmler-Behnke M, Lipka J, Wenk A, Hirn S, Schäffler M, Schmid G, Simon U, Kreyling WG. Size and surface charge of gold nanoparticles determine absorption across intestinal barriers and accumulation in secondary target organs after oral administration. Nanotoxicology 2011; 6:36-46. [PMID: 21309618 PMCID: PMC3267526 DOI: 10.3109/17435390.2011.552811] [Citation(s) in RCA: 230] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It is of urgent need to identify the exact physico-chemical characteristics which allow maximum uptake and accumulation in secondary target organs of nanoparticulate drug delivery systems after oral ingestion. We administered radiolabelled gold nanoparticles in different sizes (1.4-200 nm) with negative surface charge and 2.8 nm nanoparticles with opposite surface charges by intra-oesophageal instillation into healthy adult female rats. The quantitative amount of the particles in organs, tissues and excrements was measured after 24 h by gamma-spectroscopy. The highest accumulation in secondary organs was mostly found for 1.4 nm particles; the negatively charged particles were accumulated mostly more than positively charged particles. Importantly, 18 nm particles show a higher accumulation in brain and heart compared to other sized particles. No general rule accumulation can be made so far. Therefore, specialized drug delivery systems via the oral route have to be individually designed, depending on the respective target organ.
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Affiliation(s)
- Carsten Schleh
- Comprehensive Pneumology Center - Institute of Lung Biology and Disease and Focus Network NP and Health, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.
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14
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Powell JJ, Faria N, Thomas-McKay E, Pele LC. Origin and fate of dietary nanoparticles and microparticles in the gastrointestinal tract. J Autoimmun 2010; 34:J226-33. [PMID: 20096538 DOI: 10.1016/j.jaut.2009.11.006] [Citation(s) in RCA: 298] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Humans have evolved with oral exposure to dietary microparticles and nanoparticles as a normal occurrence but the ever-growing exploitation of nanotechnology is likely to increase exposure further, both qualitatively and quantitatively. Moreover, unlike the situation with respirable particles, relatively little is known about gastrointestinal intake and handling of nanoparticles. With a long term interest in gut exposure and responses to dietary microparticles, our group is now applying its expertise to nanoparticles in the gastrointestinal tract. Here we aim to address (i) the current challenges associated with the characterisation of particle-host or particle-cell interactions, (ii) the origin and mechanisms of uptake of particles in the gastrointestinal tract, especially via the Peyer's patch and (iii) potential cellular effects of nanoparticles in the generation of reactive oxygen species and inflammasome activation, or microparticles in their adjuvant activity in pro-inflammatory signalling and immune responsiveness.
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Affiliation(s)
- Jonathan J Powell
- Elsie Widdowson Laboratory, MRC-HNR, Fulbourn Road, Cambridge CB1 9NL, UK.
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15
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Boverhof DR, David RM. Nanomaterial characterization: considerations and needs for hazard assessment and safety evaluation. Anal Bioanal Chem 2009; 396:953-61. [DOI: 10.1007/s00216-009-3103-3] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2009] [Revised: 08/21/2009] [Accepted: 08/23/2009] [Indexed: 11/29/2022]
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Circulation and long-term fate of functionalized, biocompatible single-walled carbon nanotubes in mice probed by Raman spectroscopy. Proc Natl Acad Sci U S A 2008; 105:1410-5. [PMID: 18230737 DOI: 10.1073/pnas.0707654105] [Citation(s) in RCA: 736] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Carbon nanotubes are promising new materials for molecular delivery in biological systems. The long-term fate of nanotubes intravenously injected into animals in vivo is currently unknown, an issue critical to potential clinical applications of these materials. Here, using the intrinsic Raman spectroscopic signatures of single-walled carbon nanotubes (SWNTs), we measured the blood circulation of intravenously injected SWNTs and detect SWNTs in various organs and tissues of mice ex vivo over a period of three months. Functionalization of SWNTs by branched polyethylene-glycol (PEG) chains was developed, enabling thus far the longest SWNT blood circulation up to 1 day, relatively low uptake in the reticuloendothelial system (RES), and near-complete clearance from the main organs in approximately 2 months. Raman spectroscopy detected SWNT in the intestine, feces, kidney, and bladder of mice, suggesting excretion and clearance of SWNTs from mice via the biliary and renal pathways. No toxic side effect of SWNTs to mice was observed in necropsy, histology, and blood chemistry measurements. These findings pave the way to future biomedical applications of carbon nanotubes.
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Yin Y, Chen D, Qiao M, Wei X, Hu H. Lectin-conjugated PLGA nanoparticles loaded with thymopentin: Ex vivo bioadhesion and in vivo biodistribution. J Control Release 2007; 123:27-38. [PMID: 17728000 DOI: 10.1016/j.jconrel.2007.06.024] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 06/13/2007] [Accepted: 06/26/2007] [Indexed: 11/25/2022]
Abstract
The conjugation of lectins onto PLGA nanoparticles has been demonstrated to effectively improve the intestinal absorption of thymopentin. In this study, thymopentin-loaded nanoparticles made from fluorescein isothiocyanate labeled PLGA were modified with wheat germ agglutinin (WGA). The specific bioadhesion of nanoparticles on rat intestinal mucosa was studied ex vivo. An important increase of interaction between WGA-conjugated nanoparticles and the intestinal segments was observed compared with that of the unconjugated one (p<0.05). Fluorescence photomicrographs confirmed the bioadhesion of WGA-conjugated nanoparticles on intestinal villous epithelium as well as Peyer's patches. Biodistribution of nanoparticles was evaluated using tissues obtained from rats, to which nanoparticles were orally administered. The highest amount of WGA-conjugated nanoparticles was detected in small intestine, suggesting an increase of intestinal bioadhesion and endocytosis. The systemic uptake was as high as 6.48-13.4% of dose at 1 day and 7.32-15.26% at 7 days, which representing an increase of almost 1.4-3.1 fold across the intestine compared to <4.9% of the unconjugated one. The enhanced uptake was related to the increasing of WGA density on nanoparticles. These results further revealed the promising potential of lectin-conjugated nanoparticles on the improvement of intestinal bioadhesion and absorption for oral drug delivery.
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Affiliation(s)
- YaShu Yin
- Department of Pharmaceutics, School of Pharmacy, Shenyang Pharmaceutical University, 103 Wenhua Road, Shenyang, Liaoning, 110016, China
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18
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Abstract
Nanotechnology, or systems/device manufacture at sizes generally ranging between 1 and 100 nm, is a multidisciplinary scientific field undergoing explosive development. The genesis of nanotechnology can be traced to advances in medicine, communications, genomics and robotics. One of the greatest values of nanotechnology will be in the development of new and effective medical treatments (i.e. nanomedicine). This review focuses on the potential of nanomedicine as it relates to the development of nanoparticles for enabling and improving the targeted delivery of therapeutic and diagnostic agents. We highlight the use of nanoparticles for specific intra-compartmental analysis using the examples of delivery to malignant cancers, to the central nervous system, and across the gastrointestinal barriers.
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Doyle-McCullough M, Smyth SH, Moyes SM, Carr KE. Factors influencing intestinal microparticle uptake in vivo. Int J Pharm 2007; 335:79-89. [PMID: 17197140 DOI: 10.1016/j.ijpharm.2006.10.043] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Revised: 10/23/2006] [Accepted: 10/28/2006] [Indexed: 01/01/2023]
Abstract
The aim of this study is to compare microparticle uptake in animals of different ages, gender and species and at different time points. The 2mum latex/in vivo in situ model uses the observation of animal responses or post-mortem changes and also particle identification by fluorescence microscopy in nine sequential intestinal segments and secondary sites. The wide size range of animals studied requires particle numbers in tissue compartments to be related to intestinal tissue section area through a circumference measurement. Area under the curve (AUC) data for particles in intestinal tissue are plotted against measurements of intestinal length, allowing comparisons to be made across different ages and species and between males and females. The percentage uptake of administered dose and particle numbers in macerated tissue are also reported. Some parameters, in particular species, do not appear to affect the extent of microparticle uptake, which ranges from 0.12 to 0.32% of the administered dose. Particle uptake does, however, vary with age, being significantly greater in young adult males (7 weeks) than in younger (3 weeks) and older (17 and 52 weeks) age groups. It is concluded that age is more important in determining the extent of uptake than gender or species.
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Affiliation(s)
- M Doyle-McCullough
- Queen's University of Belfast, School of Medicine & Dentistry, 71 University Road, Belfast BT7 1NN, United Kingdom.
| | - S H Smyth
- Queen's University of Belfast, School of Medicine & Dentistry, 71 University Road, Belfast BT7 1NN, United Kingdom
| | - S M Moyes
- Department of Physiology, Anatomy and Genetics, Le Gros Clark Building, University of Oxford, United Kingdom
| | - K E Carr
- Department of Physiology, Anatomy and Genetics, Le Gros Clark Building, University of Oxford, United Kingdom
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Yuji M, Fujimoto M, Miyata H, Inamoto T, Qi WM, Yamamoto K, Warita K, Yokoyama T, Hoshi N, Kitagawa H. Persorption Mechanisms of Luminal Antigenic Particulates via Apoptotic Epithelial Cells of Intestinal Villi into Systemic Blood Circulation in Orally Immunized Rats. J Vet Med Sci 2007; 69:339-46. [PMID: 17485920 DOI: 10.1292/jvms.69.339] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The possibility of persorption of prefixed bovine serum albumin-coated sheep erythrocytes (BSA-SEs) from mucous epithelial cells and its mechanisms were investigated in rats orally immunized by BSA for 14 consecutive days. On the day after the final oral immunization, the rats were duodenally perfused by BSA-SEs or non-coated SEs. BSA-SEs were also duodenally perfused in non-immunized rats. Thirty min after perfusion, BSA-SEs were significantly more engulfed by late-apoptotic-stage villous columnar epithelial cells in the orally immunized rats than those in other experiments. The specific antibody (SpAb) was detected on the surfaces of BSA-SEs in rats with oral immunization. In Peyer's patches of all animals, no SEs reached the follicle-associated epithelium, because of the close attachment of follicle-associated intestinal villi and the thick mucous layer. BSA-SEs were more frequently persorbed into portal blood in the orally immunized rats than in other rats. Small numbers of BSA-SEs or SEs were detected in the systemic blood of all animals. BSA-SEs were also histologically found in the blood vessels of the liver, but not in mesenteric lymph nodes. These findings suggest that sensitized antigenic particulates are taken up by late-apoptotic-stage villous columnar epithelial cells in the small intestine and are finally persorbed into the systemic blood circulation. The uptake of antigenic particulates might be mediated by its luminal SpAb.
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Affiliation(s)
- Midori Yuji
- Department of Bioresource and Agrobiosciences, Graduate School of Science and Technology, Kobe University, Japan
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Shakweh M, Ponchel G, Fattal E. Particle uptake by Peyer's patches: a pathway for drug and vaccine delivery. Expert Opin Drug Deliv 2005; 1:141-63. [PMID: 16296726 DOI: 10.1517/17425247.1.1.141] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Particle uptake by Peyer's patches offers the possibility of tailoring vaccines that can be delivered orally. However, particle uptake by the follicle-associated epithelium in the gastrointestinal tract depends on several different factors that are the physicochemical properties of the particles, the physiopathological state of the animal, the analytical method used to evaluate the uptake and finally the experimental model. These parameters do not allow a clear idea about the optimal conditions to target the Peyer's patches. The goal of this review is to clarify the role of each factor in this uptake.
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Affiliation(s)
- Monjed Shakweh
- University of Paris-South, Faculty of Pharmacy, UMR CNRS 8612, 5 rue Jean-Batiste Clement, 92290 Chatenay-Malabry Cedex, France
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Hussain N. Fluorometric method for the simultaneous quantitation of differently-sized nanoparticles in rodent tissue. Int J Pharm 2001; 214:55-61. [PMID: 11282237 DOI: 10.1016/s0378-5173(00)00631-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The oral absorption and systemic translocation of particulate matter via the gastrointestinal tract has been shown by a number of laboratories using a wide variety of particles in different animal species. While there is debate on the magnitude of particle intestinal translocation, which is encumbered by the differing experimental protocols, particularly the method of quantitation of absorbed material, few have sought to examine the pharmacokinetic aspects of particle absorption. We describe in this communication the development of a simple and a rapid fluorometric assay of quantifying tissue-laden fluorescent nanoparticles that is able to isolate, detect and quantify the presence of two or more particle populations differing both in their size and fluorescent label. Six types of polystyrene nanoparticles incorporating different fluorescent markers were spiked in whole livers. The fluorophores were extracted using our previously developed method of freeze-drying the tissue and using chloroform as the extractive solvent. Only two types of particle populations, orange-labelled 40 nm and Fluoroscein-emitting 500 nm nanoparticles, were sufficiently recoverable and provided a high signal-to-noise ratio for further work. The amount of tissue and type of biological tissue type also impacted on the nanoparticle recovery and detection, reflecting, perhaps, the quenching effects of interacting tissue-derived molecules. In addition, the results also indicate that the use of nanoparticles incorporating fluorescent dyes that have emission over 500 nm overcome the tissue interfering autofluorescence for low doses of nanoparticles. The use of this fluorometric method has several advantages compared with other modes of quantitation in that it is rapid, non-radioactive and the marker is non-leaching. More importantly, it allows the simultaneous detection of multiple fluorophores such that two or more different fluorescent particle populations can be detected in the same sample. This may enable the uncharted area of pharmacokinetic parameters, such as the impedance, augmentation or site of gut uptake of differently sized particles to be studied.
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Affiliation(s)
- N Hussain
- Centre for Drug Delivery Research, 29-39 Brunswick Square, The School of Pharmacy, University of London, London WC1N 1AX, UK.
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Araujo L, Sheppard M, Löbenberg R, Kreuter J. Uptake of PMMA nanoparticles from the gastrointestinal tract after oral administration to rats: modification of the body distribution after suspension in surfactant solutions and in oil vehicles. Int J Pharm 1999. [DOI: 10.1016/s0378-5173(98)00314-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Löbenberg R, Maas J, Kreuter J. Improved body distribution of 14C-labelled AZT bound to nanoparticles in rats determined by radioluminography. J Drug Target 1998; 5:171-9. [PMID: 9606007 DOI: 10.3109/10611869808995872] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The objective of the present study is to visualize differences in the body distribution between radiolabelled AZT bound to nanoparticles and a control solution. Polyhexylcyanoacrylate nanoparticles were manufactured by emulsion polymerization in the presence of AZT and an ionic emulsifier, bis(2-ethylhexyl) sulfosuccinate sodium. The AZT-control solution was equally prepared, but contained no monomer. The two preparations were administered either by i.v. injection or perorally by gavage. After determined time points the animals were sacrificed using carbon dioxide. The cadavers were shock-frozen in cellulose gel and cut into slices using a cryomicrotome. The tissue cross sections were fixed on an adhesive tape and then were freeze dried. The quantification of the radioactive AZT in the different organs and tissues was performed by radioluminography, and the images were generated on a computer. After i.v. injection of AZT-nanoparticles, a high amount of the AZT label was found in the organs belonging to the reticuloendothelial system. In these organs the radioactivity was inhomogeneously distributed showing that the uptake of the particle-associated radioactivity depended on the type of the cells located in the organs and was consistent with uptake by macrophages. The highest radioactivities were found in the GI-tract and in the liver. A difference in the elimination pathway between AZT-control solution and AZT bound to nanoparticles also was visible on the images. Similar results were obtained after oral administration. Of course, with the latter route a larger portion of AZT remained in the GI-tract especially after administration of nanoparticle-bound drug. These results confirmed those obtained by a classically performed quantitative whole body distribution study using liquid scintillation. This demonstrates that radioluminography is a useful method to study the organ distribution of drugs bound to nanoparticles.
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Affiliation(s)
- R Löbenberg
- Department of Pharmaceutical Technology, Johann Wolfgang Goethe-University, Frankfurt, Germany
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Abstract
This mini-review covers some of the historical and recent arguments over the experimental evidence on the uptake by and translocation from the intestinal mucosa of microparticulates after oral administration. It is concluded that there is now no dispute over the fact that this is a normal occurrence. Particulate uptake does take place, not only via the M-cells in the Peyer's patches and the isolated follicles of the gut-associated lymphoid tissue, but also via the normal intestinal enterocytes. Factors affecting uptake include particle size, surface charge and hydrophobicity and the presence or absence of surface ligands. The covalent attachment of lectin or invasion molecules to the surface of carrier particles leads to greater systemic uptake. Whether or not the route can be utilized for the routine administration of therapeutic agents which are not normally absorbed from the gut is not yet proven. Many studies show that 2-3% of the ingested dose of submicron particles can be absorbed. The increasing diversity of carrier systems, which includes dendrimers and liposomes, needs to be exploited fully. More also must be learned about the inter- and intra-subject variability of lymphoid tissue so that appropriate selectivity can be achieved through the design of specific carriers.
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Affiliation(s)
- A T Florence
- Centre for Drug Delivery Research, School of Pharmacy, University of London, United Kingdom
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