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1.
Sci Rep ; 14(1): 2499, 2024 01 30.
Article in English | MEDLINE | ID: mdl-38291095

ABSTRACT

Diabetes is a serious health issue that can be a great risk factor related to numerous physical problems. A class of drugs "Gliflozin" especially Sodium Glucose Co. Transporter 2 was inhibited by a novel drug, which is known as "empagliflozin". While ZnO nanoparticles (NPs) had considerable promise for combating diabetes, it was employed in the treatment and management of type-2 diabetes mellitus. The new drug empagliflozin was initially incorporated into Zinc Oxide NPs in this study using the surface physio-sorption technique, and the degree of drug adsorption was assessed using the HPLC method. The tailored product was characterized by using the FTIR, EDX, Ultraviolet-Visible, XRD and SEM techniques. With an average particle size of 17 nm, SEM revealed mono-dispersion of NPs and sphere-like form. The Freundlich isotherm model best fits and explains the data for the physio-sorption investigation, which examined adsorption capabilities using adsorption isotherms. The enzymes α-amylase and α-glucosidase, which are involved in the human metabolism of carbohydrates, were used in the in-vitro anti-diabetic assays. It was discovered that the composite showed the highest levels of 81.72 and 92.77% inhibition of -α-amylase and -glucosidase at an absolute concentration of 1000 µg per ml with IC50 values of 30.6 µg per ml and 72 µg per ml.


Subject(s)
Benzhydryl Compounds , Diabetes Mellitus, Type 2 , Glucosides , Metal Nanoparticles , Nanoparticles , Zinc Oxide , Humans , Zinc Oxide/pharmacology , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/pharmacology , alpha-Amylases , Anti-Bacterial Agents/pharmacology , Plant Extracts
2.
Saudi Pharm J ; 31(11): 101823, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37965293

ABSTRACT

Thymidine phosphorylase (TP) is an angiogenic enzyme. It is crucial for the development, invasion and metastasis of tumors as well as angiogenesis. In our current research, we examine how structurally changing bis-thiadiazole bearing bis-schiff bases affects their ability to inhibit TP. Through the oxidative cyclization of pyridine-based bis-thiosemicarbazone with iodine, a series of fourteen analogs of bis-thiadiazole-based bis-imines with pyridine moiety were developed. Newly synthesized scaffolds were assessed in vitro for their thymidine phosphorylase inhibitory potential and showed moderate to good inhibition profile. Eleven scaffolds such as 4a-4d,4f-4 h and 4j-4 m were discovered to be more effective than standard drug at inhibiting the thymidine phosphorylase enzyme with IC50 values of 1.16 ± 1.20, 1.77 ± 1.10, 2.48 ± 1.30, 12.54 ± 1.60, 14.63 ± 1.70, 15.53 ± 1.80, 17.47 ± 1.70, 18.98 ± 1.70, 19.53 ± 1.50, 22.73 ± 2.40 and 24.87 ± 2.80 respectively, while remaining three analogs such as 4n, 4i and 4ewere found to be more potent, but they were less potent than the standard drug. All analogs underwent SAR studies based on the pattern of substitutions around the aryl part of the bis-thiadiazole skeleton. The most active analogs in the synthesized series were then molecular docking study performed to investigate their interactions of active part of enzyme. The results showed that remarkable interactions were exhibited by these analogs with the targeted enzymes active sites. Furthermore, to confirm the structure of synthesized analogs by employing spectroscopic tools such as HREI-MS and NMR.

3.
Bioorg Chem ; 141: 106868, 2023 12.
Article in English | MEDLINE | ID: mdl-37738768

ABSTRACT

The identification of effective and druggable cholinesterase inhibitors to treat progressive neurodegenerative Alzheimer's disorder remains a continuous drug discovery hunt. In this perspective, the present study investigates the design and discovery of pyrimidine-morpholine hybrids (5a-l) as potent cholinesterase inhibitors. Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction was employed to introduce the structural diversity on the pyrimidine heterocyclic core. A range of commercially available boronic acids was successfully coupled showing a high functional group tolerance. In vitro cholinesterase inhibitory potential using Ellman's method revealed significantly strong potency. Compound 5h bearing a meta-tolyl substituent at 2-position of pyrimidine ring emerged as a lead candidate against AChE with an inhibitory potency of 0.43 ± 0.42 µM, ∼38-fold stronger value than neostigmine (IC50 = 16.3 ± 1.12 µM). Compound 5h also showed the lead inhibition against BuChE with an IC50 value of 2.5 ± 0.04 µM. The kinetics analysis of 5h revealed the non-competitive mode of inhibition against AChE whereas computational modelling results of potent leads depicted diverse contacts with the binding site amino acid residues. Molecular dynamics simulations revealed the stability of biomolecular system, while, ADME analysis demonstrated druglikeness behaviour of potent compounds. Overall, the investigated pyrimidine-morpholine scaffold presented a remarkable potential to be developed as efficacious anti-Alzheimer's drugs.


Subject(s)
Alzheimer Disease , Cholinesterase Inhibitors , Humans , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/therapeutic use , Cholinesterase Inhibitors/chemistry , Alzheimer Disease/drug therapy , Alzheimer Disease/metabolism , Molecular Structure , Acetylcholinesterase/metabolism , Morpholines/pharmacology , Morpholines/chemistry , Pyrimidines/pharmacology , Pyrimidines/therapeutic use , Molecular Docking Simulation , Structure-Activity Relationship
4.
Sci Rep ; 13(1): 15555, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37730819

ABSTRACT

A flexible wearable electrode consisting of nickel-cobalt sulfide (NCS) nanowires was fabricated in this study. Self-supporting NCS was grown in situ on porous carbon nanofibers without a binder as a novel material for supercapacitor electrodes. The NCS nanowires were grown using cyclic voltammetry electrodeposition, which proved to be a fast and environmentally friendly method with good controllability of the material structure. One-dimensional carbon nanofibers (C) have high surface-area-to-volume ratios, short ion transmission distances, excellent mechanical strengths, and remarkable flexibilities. Moreover, the NCS@C flexible electrode exhibited a synergetic effect with the active compounds, and the dense active sites were uniformly distributed across the entire surface of the carbon fibers, enabling rapid electron transport and enhancing the electrochemical properties of the NCS@C nanowires. The NCS@C achieved specific capacitances of 334.7 and 242.0 mAh g-1 at a current density of 2 A g-1 and high current densities (up to 40 A g-1), respectively, corresponding to a 72.3% retention rate. An NCS@C-nanofilm-based cathode and an activated-carbon-based anode were used to fabricate a flexible asymmetric supercapacitor. The device exhibited high energy and power densities of 12.91 Wh kg-1 and 358 W kg-1, respectively.

5.
RSC Adv ; 13(33): 23087-23121, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37529365

ABSTRACT

Targeted delivery of drug molecules to diseased sites is a great challenge in pharmaceutical and biomedical sciences. Fabrication of drug delivery systems (DDS) to target and/or diagnose sick cells is an effective means to achieve good therapeutic results along with a minimal toxicological impact on healthy cells. Biopolymers are becoming an important class of materials owing to their biodegradability, good compatibility, non-toxicity, non-immunogenicity, and long blood circulation time and high drug loading ratio for both macros as well as micro-sized drug molecules. This review summarizes the recent trends in biopolymer-based DDS, forecasting their broad future clinical applications. Cellulose chitosan, starch, silk fibroins, collagen, albumin, gelatin, alginate, agar, proteins and peptides have shown potential applications in DDS. A range of synthetic techniques have been reported to design the DDS and are discussed in the current study which is being successfully employed in ocular, dental, transdermal and intranasal delivery systems. Different formulations of DDS are also overviewed in this review article along with synthesis techniques employed for designing the DDS. The possibility of these biopolymer applications points to a new route for creating unique DDS with enhanced therapeutic qualities for scaling up creative formulations up to the clinical level.

6.
Sensors (Basel) ; 23(4)2023 Feb 11.
Article in English | MEDLINE | ID: mdl-36850655

ABSTRACT

Reduced graphene oxide (rGO) is a derivative of graphene, which has been widely used as the conductive pigment of many water-based inks and is recognized as one of the most promising graphene-based materials for large-scale and low-cost production processes. In this work, we evaluate a custom functionalised reduced graphene oxide ink (f-rGO) via inkjet-printing technology. Test line structures were designed and fabricated by the inkjet printing process using the f-rGO ink on a pretreated polyimide substrate. For the electrical characterisation of these devices, two-point (2P) and four-point (4P) probe measurements were implemented. The results showed a major effect of the number of printed passes on the resulting resistance for all ink concentrations in both 2P and 4P cases. Interesting results can be extracted by comparing the obtained multipass resistance values that results to similar effective concentration with less passes. These measurements can provide the ground to grasp the variation in resistance values due to the different ink concentrations, and printing passes and can provide a useful guide in achieving specific resistance values with adequate precision. Accompanying topography measurements have been conducted with white-light interferometry. Furthermore, thermal characterisation was carried out to evaluate the operation of the devices as temperature sensors and heaters. It has been found that ink concentration and printing passes directly influence the performance of both the temperature sensors and heaters.

7.
Am J Pathol ; 193(1): 27-38, 2023 01.
Article in English | MEDLINE | ID: mdl-36309105

ABSTRACT

Inadequate DNA damage response related to ataxia telangiectasia mutated gene restricts hepatic regeneration in acute liver failure. Resolving mechanistic gaps in liver damage and repair requires additional animal models that are unconstrained by ultrarapid and unpredictable mortalities or substantial divergences from human pathology. This study used Fischer 344 rats primed with the antitubercular drug, rifampicin, plus phenobarbitone, and monocrotaline, a DNA adduct-forming alkaloid. Rifampicin and monocrotaline can cause liver failure in people. This regimen resulted in hepatic oxidative stress, necrosis, DNA double-strand breaks, liver test abnormalities, altered serum cytokine expression, and mortality. Healthy donor hepatocytes were transplanted ectopically in the peritoneal cavity to study whether they could supply metabolic support and rebalance inflammatory or protective cytokines affecting liver regeneration events. Hepatocyte transplantation increased candidate cytokine levels (granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon-γ, IL-10, and IL-12), leading to Atm, Stat3, and Akt signaling in hepatocytes and nonparenchymal cells, lowering of inflammation, and improvements in intermediary metabolism, DNA repair, and hepatocyte proliferation. Such control of DNA damage and inflammation, along with stimulation of hepatic growth, offers paradigms for cell signaling to restore hepatic homeostasis and regeneration in acute liver failure. Further studies of molecular pathways of high pathobiological impact will advance the knowledge of liver regeneration.


Subject(s)
Ataxia Telangiectasia , Liver Failure, Acute , Rats , Humans , Animals , Ataxia Telangiectasia/metabolism , Ataxia Telangiectasia/pathology , Monocrotaline/metabolism , Rifampin/metabolism , Cytokines/metabolism , Liver Failure, Acute/metabolism , Liver/metabolism , Liver Regeneration/physiology , Hepatocytes/pathology , Rats, Inbred F344 , Inflammation/pathology
8.
FASEB J ; 35(4): e21471, 2021 04.
Article in English | MEDLINE | ID: mdl-33683737

ABSTRACT

Acute liver failure constitutes a devastating condition that needs novel cell and molecular therapies. To elicit synergisms in cell types of therapeutic interest, we studied hepatocytes and liver sinusoidal endothelial in mice with acetaminophen-induced acute liver failure. The context of regenerative signals was examined by transplants in peritoneal cavity because it possesses considerable capacity and allows soluble signals to enter the systemic circulation. Whereas transplanted hepatocytes and liver sinusoidal endothelial cells engrafted in peritoneal cavity, only the former could rescue mice in liver failure by improving injury outcomes, activating hepatic DNA damage repair, and inducing liver regeneration. The cytokines secreted by donor hepatocytes or liver sinusoidal endothelial cells differed and in hepatocytes from mice undergoing acetaminophen toxicity major cytokines were even rendered deficient (eg, G-CSF, VEGF, and others). Significantly, recapitulating hepatotoxicity-related DNA damage response in cultured cells identified impairments in ATM and JAK/STAT3 intersections since replacing cytokines produced less from injured hepatocytes restored these pathways to avoid acetaminophen hepatotoxicity. Similarly, hepatocyte transplantation in acute liver failure restored ATM and JAK/STAT3 pathways to advance DNA damage/repair and liver regeneration. The unexpected identification of novel hepatic G-CSF receptor expression following injury allowed paradigmatic studies of G-CSF supplementation to confirm the centrality of this paracrine ATM and STAT3 intersection. Remarkably, DNA damage/repair and hepatic regeneration directed by G-CSF concerned rebalancing of regulatory gene networks overseeing inflammation, metabolism, and cell viability. We conclude that healthy donor hepatocytes offer templates for generating specialized cell types to replace metabolic functions and regenerative factors in liver failure.


Subject(s)
Chemical and Drug Induced Liver Injury/drug therapy , Endothelial Cells/drug effects , Hepatocytes/cytology , Liver Failure, Acute/therapy , Liver Regeneration/drug effects , Acetaminophen/pharmacology , Animals , Cell Survival/physiology , Chemical and Drug Induced Liver Injury/metabolism , Humans , Liver Failure, Acute/chemically induced , Liver Failure, Acute/metabolism , Liver Regeneration/physiology , STAT3 Transcription Factor/metabolism
9.
Sci Rep ; 11(1): 1867, 2021 01 21.
Article in English | MEDLINE | ID: mdl-33479329

ABSTRACT

In this study, a combination of reverse microemulsion and hydrothermal techniques were used to synthesize HA. A hydrothermal method was used to synthesize HA/TiO2/CNT nanocomposite powders. Cold and hot isostatic pressing techniques were used to fabricate tablet-shaped samples. To investigate the biocompatibility and tribo-mechanical properties of HA/TiO2 and HA/TiO2/CNTs, four samples were prepared with different percentages of CNTs, namely, HA/TiO2 (S0), HA/TiO2/CNT (S1.0), HA/TiO2/CNT (S2.0), and HA/TiO2/CNT (S3.0). The microstructure and morphology of the HA/TiO2/CNTs were characterized by transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. Hardness test results show that S3.0 displayed the highest surface hardness (285 HV) compared to other samples. The wear rate of HA/TiO2/CNT with the highest CNT content showed a decrease compared with those of the other samples. The results from nanoindentation tests showed that Young's modulus of the S3.0 sample was 58.1% greater than that of the S0 sample. Furthermore, the human MDA-MB-231 cell line demonstrated good binding to the surface of the samples in the in-vitro biocompatibility evaluation of the HA/TiO2/CNT composites.

10.
Am J Pathol ; 191(1): 79-89, 2021 01.
Article in English | MEDLINE | ID: mdl-33127336

ABSTRACT

The innate immune system plays a critical role in allograft rejection. Alloresponses involve numerous cytokines, chemokines, and receptors that cause tissue injury during rejection. To dissect these inflammatory mechanisms, we developed cell transplantation models in dipeptidylpeptidase-deficient F344 rats using mycophenolate mofetil and tacrolimus for partial lymphocyte-directed immunosuppression. Syngeneic hepatocytes engrafted in liver, whereas allogeneic hepatocytes were rejected but engrafted after immunosuppression. These transplants induced mRNAs for >40 to 50 cytokines, chemokines, and receptors. In allografts, innate cell type-related regulatory networks extended to granulocytes, monocytes, and macrophages. Activation of Tnfa and its receptors or major chemokine receptor-ligand subsets persisted in the long term. An examination of the contribution of Tnfa in allograft response revealed that it was prospectively antagonized by etanercept or thalidomide, which resolved cytokine, chemokine, and receptor cascades. In bioinformatics analysis of upstream regulator networks, the Cxcl8 pathway exhibited dominance despite immunosuppression. Significantly, Tnfa antagonism silenced the Cxcl8 pathway and decreased neutrophil and Kupffer cell recruitment, resulting in multifold greater engraftment of allogeneic hepatocytes and substantially increased liver repopulation in retrorsine/partial hepatectomy model. We conclude that Tnfa is a major driver for persistent innate immune responses after allogeneic cells. Neutralizing Tnfa should help in avoiding rejection and associated tissue injury in the allograft setting.


Subject(s)
Graft Rejection/immunology , Hepatocytes/transplantation , Immunity, Innate/immunology , Transplantation Immunology/immunology , Tumor Necrosis Factor-alpha/immunology , Allografts , Animals , Rats , Rats, Inbred F344 , Rats, Long-Evans , Transplantation, Homologous
11.
Comput Math Methods Med ; 2020: 6718495, 2020.
Article in English | MEDLINE | ID: mdl-32724330

ABSTRACT

As many as 80% of patients with TAR die on the spot while out of those reaching a hospital, 30% would die within 24 hours. Thus, it is essential to better understand and prevent this injury. The exact mechanics of TAR are unknown. Although most researchers approve it as a common-sense deceleration injury, the exact detailed mechanism of TRA still remains unidentified. In this work, a deceleration mechanism of TAR was carried out using finite element analysis (FEA). The FE analysis aimed to predict internal kinematics of the aorta and assist to comprehend the mechanism of aorta injury. The model contains the heart, lungs, thoracic aorta vessel, and rib cage. High-resolution computerized tomography (HR CT scan) was used to provide pictures that were reconstructed by MIMICS software. ANSYS FE simulation was carried out to investigate the behavior of the aorta in the thoracic interior after deceleration occurred during a car crash. The finite element analysis indicated that maximum stress and strain applied to the aorta were from 5.4819e5 to 2.614e6 Pa and 0.21048 to 0.62676, respectively, in the Y-direction when the initial velocity increased from 10 to 25 m/s. Furthermore, in the X-direction when the velocity changed from 15 to 25 m/s, the stress and strain values increased from 5.17771e5 to 2.3128e6 and from 0.22445 to 0.618, respectively.


Subject(s)
Aorta/injuries , Aortic Rupture/etiology , Models, Cardiovascular , Myocardial Contusions/etiology , Acceleration/adverse effects , Accidents, Traffic , Aortic Rupture/pathology , Aortic Rupture/physiopathology , Biomechanical Phenomena , Computational Biology , Computer Simulation , Finite Element Analysis , Humans , Imaging, Three-Dimensional , Mathematical Concepts , Myocardial Contusions/pathology , Myocardial Contusions/physiopathology , Stress, Mechanical , Tomography, X-Ray Computed
12.
Nanomaterials (Basel) ; 10(3)2020 Mar 23.
Article in English | MEDLINE | ID: mdl-32210107

ABSTRACT

In this study, to fabricate a non-binder electrode, we grew nickel-cobalt sulfide (NCS) nanotubes (NTs) on a Ni foam substrate using a hydrothermal method through a two-step approach, namely in situ growth and an anion-exchange reaction. This was followed by the electrodeposition of double-layered nickel-cobalt hydroxide (NCOH) over a nanotube-coated substrate to fabricate NCOH core-shell nanotubes. The final product is called NCS@NCOH herein. Structural and morphological analyses of the synthesized electrode materials were conducted via SEM and XRD. Different electrodeposition times were selected, including 10, 20, 40, and 80 s. The results indicate that the NCSNTs electrodeposited with NCOH nanosheets for 40 s have the highest specific capacitance (SC), cycling stability (2105 Fg-1 at a current density of 2 Ag-1), and capacitance retention (65.1% after 3,000 cycles), in comparison with those electrodeposited for 10, 20, and 80 s. Furthermore, for practical applications, a device with negative and positive electrodes made of active carbon and NCS@NCOH was fabricated, achieving a high-energy density of 23.73 Whkg-1 at a power density of 400 Wkg-1.

13.
Hepatol Commun ; 3(1): 129-146, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30620000

ABSTRACT

Hepatocyte transplantation is an attractive alternative to liver transplantation. Thus far, however, extensive liver repopulation by adult hepatocytes has required ongoing genetic, physical, or chemical injury to host liver. We hypothesized that providing a regulated proliferative and/or survival advantage to transplanted hepatocytes should enable repopulation in a normal liver microenvironment. Here, we repopulated livers of DPPIV- (dipeptidyl peptidase-4) rats and Ugt1a1 (uridinediphosphoglucuronate glucuronosyltransferase 1a1)-deficient Gunn rats (model of Crigler-Najjar syndrome type 1), both models without underlying liver injury, for up to 1 year by transplanting lenti-hYAP-ERT2 (mutated estrogen receptor ligand-binding domain 2)-transduced hepatocytes (YAP-Hc). Yap (yes-associated protein) nuclear translocation/function in YAP-Hc was regulated by tamoxifen. Repopulating YAP-Hc and host hepatocytes were fluorescence-activated cell sorting-purified and their transcriptomic profiles compared by RNAseq. After 1 year of liver repopulation, YAP-Hc clusters exhibited normal morphology, integration into hepatic plates and hepatocyte-specific gene expression, without dysplasia, dedifferentiation, or tumorigenesis. RNAseq analysis showed up-regulation of 145 genes promoting cell proliferation and 305 genes suppressing apoptosis, including hepatocyte growth factor and connective tissue growth factor among the top 30 in each category and provided insight into the mechanism of cell competition that enabled replacement of host hepatocytes by YAP-Hc. In Gunn rats transplanted with YAP-Hc+tamoxifen, there was a 65%-81% decline in serum bilirubin over 6 months versus 8%-20% with control-Hc, representing a 3-4-fold increase in therapeutic response. This correlated with liver repopulation as demonstrated by the presence of Ugt1a1-positive hepatocyte clusters in livers and western blot analysis of tissue homogenates. Conclusion: Tamoxifen-regulated nuclear translocation/function of hYAP-ERT2 enabled long-term repopulation of DPPIV-/- and Gunn rat livers by hYAP-ERT2-transduced hepatocytes without tumorigenesis. This cell transplantation strategy may offer a potential therapy for most of the inherited monogenic liver diseases that do not exhibit liver injury.

14.
Hum Gene Ther ; 30(3): 365-377, 2019 03.
Article in English | MEDLINE | ID: mdl-30266073

ABSTRACT

Reconstitution of healthy endothelial cells in vascular beds offers opportunities for mechanisms in tissue homeostasis, organ regeneration, and correction of deficient functions. Liver sinusoidal endothelial cells express unique functions, and their transplantation is relevant for disease models and for cell therapy. As molecular targets for improving transplanted cell engraftment and proliferation will be highly significant, this study determined whether ETA/B receptor antagonism by the drug bosentan could overcome cell losses due to cell transplantation-induced cytotoxicity. Cell engraftment and proliferation assays were performed with healthy wild-type liver sinusoidal endothelial cells transplanted into the liver of dipeptidylpeptidase IV knockout mice. Transplanted cells were identified in tissues by enzyme histochemistry. Cells with prospective ETA/B antagonism engrafted significantly better in hepatic sinusoids. Moreover, these cells underwent multiple rounds of division under liver repopulation conditions. The gains of ETA/B antagonism resulted from benefits in cell viability and membrane integrity. Also, in bosentan-treated cells, mitochondrial homeostasis was better maintained with less oxidative stress and DNA damage after injuries. Intracellular effects of ETA/B antagonism were transduced by conservation of ataxia telangiectasia mutated protein, which directs DNA damage response. Therefore, ETA/B antagonism in donor cells will advance vascular reconstitution. Extensive experience with ETA/B antagonists will facilitate translation in people.


Subject(s)
Endothelial Cells/drug effects , Endothelial Cells/metabolism , Endothelin Receptor Antagonists/pharmacology , Liver/blood supply , Liver/drug effects , Microvessels/drug effects , Animals , Cell Survival/drug effects , Cytoskeleton/metabolism , DNA Damage , Dipeptidyl Peptidase 4/deficiency , Liver/metabolism , Liver/pathology , Membrane Potential, Mitochondrial/drug effects , Mice , Mice, Knockout , Mitochondria, Liver/drug effects , Mitochondria, Liver/metabolism , Models, Biological , Oxidative Stress , Reactive Oxygen Species/metabolism
15.
Methods Mol Biol ; 1506: 161-178, 2017.
Article in English | MEDLINE | ID: mdl-27830552

ABSTRACT

Wilson's disease (WD) is characterized by the inability to excrete copper (Cu) from the body with progressive tissue injury, especially in liver and brain. The molecular defect in WD concerns mutations in ATP7B gene leading to loss of Cu transport from the hepatocyte to the bile canaliculus. While drugs, e.g., Cu chelators, have been available for several decades, these must be taken lifelong, which can be difficult due to issues of compliance or side effects. Many individuals may require liver transplantation, which can also be difficult due to donor organ shortages. Therefore, achieving permanent cures via cell or gene therapy are of great interest for WD. Cell therapy is feasible because transplanted hepatocytes can integrate in liver parenchyma and restore deficient functions, including transport of Cu into bile. The availability of authentic animal models that recapitulate hepatic WD, especially the Long-Evans Cinnamon (LEC) rat, has advanced cell transplantation research in WD. We describe requirements for cell therapy in animal models with several standardized methods for studies to test or refine cell therapy strategies in WD.


Subject(s)
Cell Transplantation/methods , Disease Models, Animal , Hepatocytes/transplantation , Hepatolenticular Degeneration/therapy , Rats, Inbred LEC/physiology , Animals , Cell Transplantation/adverse effects , Cell Transplantation/instrumentation , Copper/metabolism , Copper-Transporting ATPases/genetics , Genetic Therapy/methods , Hepatobiliary Elimination , Hepatolenticular Degeneration/genetics , Hepatolenticular Degeneration/pathology , Humans , Liver/cytology , Liver/pathology , Liver/surgery , Liver Transplantation/adverse effects , Mutation , Rats , Rats, Inbred LEC/surgery
16.
Sci Rep ; 6: 19275, 2016 Jan 14.
Article in English | MEDLINE | ID: mdl-26763940

ABSTRACT

Liver repopulation by transplanted hepatocytes has not been achieved previously in a normal liver microenvironment. Here we report that adult rat hepatocytes transduced ex vivo with a lentivirus expressing a human YapERT2 fusion protein (hYapERT2) under control of the hepatocyte-specific transthyretin (TTR) promoter repopulate normal rat liver in a tamoxifen-dependent manner. Transplanted hepatocytes expand very slowly but progressively to produce 10% repopulation at 6 months, showing clusters of mature hepatocytes that are fully integrated into hepatic parenchyma, with no evidence for dedifferentiation, dysplasia or malignant transformation. Thus, we have developed the first vector designed to regulate the growth control properties of Yap that renders it capable of producing effective cell therapy. The level of liver repopulation achieved has significant translational implications, as it is 2-3x the level required to cure many monogenic disorders of liver function that have no underlying hepatic pathology and is potentially applicable to diseases of other tissues and organs.


Subject(s)
Cell- and Tissue-Based Therapy , Hepatocytes/metabolism , Nuclear Proteins/genetics , Prealbumin/genetics , Promoter Regions, Genetic , Recombinant Fusion Proteins , Transcription Factors/genetics , Transduction, Genetic , Animals , Cell Cycle Proteins , Gene Expression , Genes, Reporter , Genetic Vectors/genetics , Hepatocytes/drug effects , Hepatocytes/transplantation , Lentivirus/genetics , Liver Regeneration , Models, Animal , Protein Transport , Rats , Tamoxifen/pharmacology
17.
J Neurosci Methods ; 182(2): 225-35, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19540265

ABSTRACT

To organise in vitro neural networks at the cellular level and study their electrical patterns, we have fabricated 4 x 4 planar microelectrode arrays using conventional photolithography. The electrode sites of these arrays are located inside micro-wells, for confining the neurons, which are connected with neighbouring wells via micro-trenches capable of guiding the outgrowth of neurites. In order to load a single neuron inside each micro-well, a simple system has been developed that utilises the phenomenon of dielectrophoresis. It operates by moving neurons towards each electrode site of an array using a dielectrophoretic force, checking for the presence of a neuron inside each micro-well using image processing, and stopping the dielectrophoretic force when detecting a neuron inside a micro-well in order to prevent more cells from being trapped. This system provides a fast, effective and inexpensive way to assemble neural grids consisting of contacts between electrodes and single neurons, as the use of micromanipulator guided micropipettes can be avoided. Spontaneous and evoked action potentials from trapped neurons were successfully recorded using a 16-channel acquisition/stimulation unit.


Subject(s)
Action Potentials/physiology , Electrophysiology/instrumentation , Neurons/physiology , Animals , Cells, Cultured , Cerebellum/cytology , Cerebellum/physiology , Electric Stimulation , Electrophoresis , Electrophysiology/methods , Equipment Design , Microelectrodes , Rats , Rats, Sprague-Dawley , Signal Processing, Computer-Assisted
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