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1.
Neuromolecular Med ; 26(1): 19, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703217

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder associated with mitochondrial dysfunctions and oxidative stress. However, to date, therapeutics targeting these pathological events have not managed to translate from bench to bedside for clinical use. One of the major reasons for the lack of translational success has been the use of classical model systems that do not replicate the disease pathology and progression with the same degree of robustness. Therefore, we employed a more physiologically relevant model involving alpha-synuclein-preformed fibrils (PFF) exposure to SH-SY5Y cells and Sprague Dawley rats. We further explored the possible involvement of transient receptor potential canonical 5 (TRPC5) channels in PD-like pathology induced by these alpha-synuclein-preformed fibrils with emphasis on amelioration of oxidative stress and mitochondrial health. We observed that alpha-synuclein PFF exposure produced neurobehavioural deficits that were positively ameliorated after treatment with the TRPC5 inhibitor clemizole. Furthermore, Clemizole also reduced p-alpha-synuclein and diminished oxidative stress levels which resulted in overall improvements in mitochondrial biogenesis and functions. Finally, the results of the pharmacological modulation were further validated using siRNA-mediated knockdown of TRPC5 channels, which also decreased p-alpha-synuclein expression. Together, the results of this study could be superimposed in the future for exploring the beneficial effects of TRPC5 channel modulation for other neurodegenerative disorders and synucleopathies.


Assuntos
Mitocôndrias , Estresse Oxidativo , Ratos Sprague-Dawley , Canais de Cátion TRPC , alfa-Sinucleína , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Animais , Ratos , Estresse Oxidativo/efeitos dos fármacos , Humanos , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/antagonistas & inibidores , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Linhagem Celular Tumoral , Masculino , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/induzido quimicamente , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , RNA Interferente Pequeno/uso terapêutico , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/tratamento farmacológico
2.
Int J Biol Macromol ; 268(Pt 1): 131476, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38614181

RESUMO

This study involved creating oligomeric conjugates of 3-hydroxy fatty acids and diclofenac, named Dic-oligo(3HAs). Advanced NMR techniques confirmed no free diclofenac in the mix. We tested diclofenac release under conditions resembling healthy and chronic wound skin. These oligomers were used to make P(3HO) blends, forming patches for drug delivery. Their preparation used the solvent casting/porogen leaching (SCPL) method. The patches' properties like porosity, roughness, and wettability were thoroughly analysed. Antimicrobial assays showed that Dic-oligo(3HAs) exhibited antimicrobial activity against reference (S. aureus, S. epidermis, S. faecalis) and clinical (Staphylococcus spp.) strains. Human keratinocytes (HaCaT) cell line tests, as per ISO 10993-5, showed no toxicity. A clear link between material roughness and HaCaT cell adhesion was found. Deep cell infiltration was verified using DAPI and phalloidin staining, observed under confocal microscopy. SEM also confirmed HaCaT cell growth on these scaffolds. The strong adhesion and proliferation of HaCaT cells on these materials indicate their potential as wound dressing layers. Additionally, the successful diclofenac release tests point to their applicability in treating both normal and chronic wounds.

3.
Drug Discov Today ; 29(5): 103974, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38555032

RESUMO

Accumulation of misfolded proteins and protein aggregates leading to degeneration of neurons is a hallmark of several neurodegenerative diseases. Therapy mostly relies on symptomatic relief. Immunotherapy offers a promising approach for the development of disease-modifying routes. Such strategies have shown remarkable results in oncology, and this promise is increasingly being realized for neurodegenerative diseases in advanced preclinical and clinical studies. This review highlights cases of passive and active immunotherapies in Parkinson's and Alzheimer's diseases. The reasons for success and failure, wherever available, and strategies to cross the blood-brain barrier, are discussed. The need for conditional modulation of the immune response is also reflected on.


Assuntos
Imunoterapia , Doenças Neurodegenerativas , Humanos , Animais , Imunoterapia/métodos , Doenças Neurodegenerativas/terapia , Doenças Neurodegenerativas/imunologia , Doença de Alzheimer/terapia , Doença de Alzheimer/imunologia , Doença de Parkinson/terapia , Doença de Parkinson/imunologia , Barreira Hematoencefálica/metabolismo
4.
Environ Monit Assess ; 196(2): 194, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265534

RESUMO

Interpretation of a fossil pollen data for the vegetation and climate reconstruction of any region needs a modern pollen-vegetation analogue for its calibration. We analyzed the surface sediments and moss polsters for the pollen and microcharcoal records to understand the modern pollen-vegetation relationship and human activities in the Baspa Valley, Kinnaur, Himachal Pradesh. Presently, valley is occupied by the arboreal and non-arboreal vegetation of temperate to subalpine habitats and land use activities. The recovered pollen assemblages showed variability in the dispersal behavior of pollen of taxa growing along the valley transect and also captured the signals of human activities over land use. The overall dominance of arboreal pollen in the recovered pollen assemblage corresponds with the dominant growth of conifers and broadleaf tree taxa and represents the valley vegetation at a regional scale. However, the profuse pollen production of a few arboreal taxa and long distance pollen transport from one vegetation zone to other by the strong upthermic valley winds could bias the pollen representation of in-situ vegetation. The high pollen frequency of non-arboreal taxa in the open meadows represents the near vicinity to their plant source. Human activities like fire burning and cultivation by the local population are evident by the recovery of microcharcoal particles and pollen of plants belonging to Cerealia Poaceae, Asteraceae, Amaranthaceae, Polygonaceae, Rosaceae, Juglandaceae, etc. The dataset taken as modern pollen-vegetation analogue is useful to assess past changes in the vegetation and land cover in relation to climate and human factors for future sustenance.


Assuntos
Meio Ambiente , Monitoramento Ambiental , Humanos , Himalaia , Pólen , Clima
5.
Tissue Eng Part A ; 30(7-8): 340-356, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37962275

RESUMO

In this study, we develop a bio-based and bioactive nanofibrous patch based on bacterial cellulose (BC) and chitin nanofibrils (CNs) using an ionic liquid as a solvent for BC, aimed at tympanic membrane (TM) repair. Electrospun BC nanofiber meshes were produced via electrospinning, and surface-modified with CNs using electrospray. The rheology of the BC/ionic liquid system was investigated. The obtained CN/BC meshes underwent comprehensive morphological, physicochemical, and mechanical characterization. Cytotoxicity tests were conducted using L929 mouse fibroblasts, revealing a cell viability of 97.8%. In vivo tests on rabbit skin demonstrated that the patches were nonirritating. Furthermore, the CN/BC fiber meshes were tested in vitro using human dermal keratinocytes (HaCaT cells) and human umbilical vein endothelial cells as model cells for TM perforation healing. Both cell types demonstrated successful growth on these scaffolds. The presence of CNs resulted in improved indirect antimicrobial activity of the electrospun fiber meshes. HaCaT cells exhibited an upregulated mRNA expression at 6 and 24 h of key proinflammatory cytokines crucial for the wound healing process, indicating the potential benefits of CNs in the healing response. Overall, this study presents a natural and eco-sustainable fiber mesh with great promise for applications in TM repair, leveraging the synergistic effects of BC and CNs to possibly enhance tissue regeneration and healing. Impact statement Repair of tympanic membrane perforations following chronic otitis media is a main clinical issue in otologic surgery, where the underlying infection obstacles self-healing. To address this challenge, our study proposes a bio-based patch made of nanoscale carbohydrate materials (i.e., bacterial cellulose electrospun fibers and chitin nanofibrils) processed via green solvents. The scaffold is nonirritating in vivo, and cytocompatible with fibroblasts, endothelial cells, and keratinocytes. In epithelial cells, it stimulates the expression of the antimicrobial peptide human beta defensin 2, with a pathway of cytokine expression compatible with the wound healing process. Therefore, it could be applied with unsolved infective pathology.


Assuntos
Líquidos Iônicos , Nanofibras , Perfuração da Membrana Timpânica , Camundongos , Animais , Humanos , Coelhos , Celulose/farmacologia , Membrana Timpânica , Quitina/farmacologia , Células Endoteliais , Nanofibras/química , Alicerces Teciduais/química
6.
Biomater Sci ; 11(17): 5706-5726, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37401545

RESUMO

Chronic Kidney Disease (CKD) is a growing worldwide problem, leading to end-stage renal disease (ESRD). Current treatments for ESRD include haemodialysis and kidney transplantation, but both are deemed inadequate since haemodialysis does not address all other kidney functions, and there is a shortage of suitable donor organs for transplantation. Research in kidney tissue engineering has been initiated to take a regenerative medicine approach as a potential treatment alternative, either to develop effective cell therapy for reconstruction or engineer a functioning bioartificial kidney. Currently, renal tissue engineering encompasses various materials, mainly polymers and hydrogels, which have been chosen to recreate the sophisticated kidney architecture. It is essential to address the chemical and mechanical aspects of the materials to ensure they can support cell development to restore functionality and feasibility. This paper reviews the types of polymers and hydrogels that have been used in kidney tissue engineering applications, both natural and synthetic, focusing on the processing and formulation used in creating bioactive substrates and how these biomaterials affect the cell biology of the kidney cells used.


Assuntos
Falência Renal Crônica , Engenharia Tecidual , Humanos , Medicina Regenerativa , Hidrogéis , Polímeros , Rim , Materiais Biocompatíveis , Falência Renal Crônica/terapia
7.
Regen Biomater ; 10: rbad063, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37501678

RESUMO

Polyhydroxyalkanoates are natural, biodegradable, thermoplastic and sustainable polymers with a huge potential in fabrication of bioresorbable implantable devices for tissue engineering. We describe a comparative evaluation of three medium chain length polyhydroxyalkanoates (mcl-PHAs), namely poly(3-hydroxyoctanoate), poly(3-hydroxyoctanoate-co-3-hydoxydecanoate) and poly(3-hydroxyoctanoate-co-3-hydroxydecanoate-co-3-hydroxydodecanoate), one short chain length polyhydroxyalkanoate, poly(3-hydroxybutyrate), P(3HB) and synthetic aliphatic polyesters (polycaprolactone and polylactide) with a specific focus on nerve regeneration, due to mechanical properties of mcl-PHAs closely matching nerve tissues. In vitro biological studies with NG108-15 neuronal cell and primary Schwann cells did not show a cytotoxic effect of the materials on both cell types. All mcl-PHAs supported cell adhesion and viability. Among the three mcl-PHAs, P(3HO-co-3HD) exhibited superior properties with regards to numbers of cells adhered and viable cells for both cell types, number of neurite extensions from NG108-15 cells, average length of neurite extensions and Schwann cells. Although, similar characteristics were observed for flat P(3HB) surfaces, high rigidity of this biomaterial, and FDA-approved polymers such as PLLA, limits their applications in peripheral nerve regeneration. Therefore, we have designed, synthesized and evaluated these materials for nerve tissue engineering and regenerative medicine, the interaction of mcl-PHAs with neuronal and Schwann cells, identifying mcl-PHAs as excellent materials to enhance nerve regeneration and potentially their clinical application in peripheral nerve repair.

8.
ACS Chem Neurosci ; 14(12): 2385-2395, 2023 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-37294284

RESUMO

Aggregation of mutant huntingtin is a pathological hallmark of Huntington's disease (HD). Protein aggregation results in various cellular dysfunctions, such as increase in oxidative stress, mitochondrial damage, proteostasis imbalance, etc., which finally cause cell death. Previously, specific RNA aptamers with high affinity for mutant huntingtin were selected. In the current study, we show that the selected aptamer inhibits aggregation of mutant huntingtin (EGFP-74Q) in HEK293 and Neuro 2a cell models of HD. The presence of aptamer decreases sequestration of chaperones and increases their cellular levels. This is accompanied by improved mitochondrial membrane permeability, reduced oxidative stress, and increased cell survival. Thus, RNA aptamers can be explored further as inhibitors of protein aggregation in protein misfolding diseases.


Assuntos
Aptâmeros de Nucleotídeos , Doença de Huntington , Humanos , Aptâmeros de Nucleotídeos/farmacologia , Aptâmeros de Nucleotídeos/metabolismo , Células HEK293 , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/metabolismo , Chaperonas Moleculares/metabolismo , Agregados Proteicos , Proteostase
9.
Macromol Biosci ; 23(11): e2300226, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37364159

RESUMO

Silane modification is a simple and cost-effective tool to modify existing biomaterials for tissue engineering applications. Aminosilane layer deposition has previously been shown to control NG108-15 neuronal cell and primary Schwann cell adhesion and differentiation by controlling deposition of ─NH2 groups at the submicron scale across the entirety of a surface by varying silane chain length. This is the first study toreport depositing 11-aminoundecyltriethoxysilane (CL11) onto aligned Polycaprolactone (PCL) scaffolds for peripheral nerve regeneration. Fibers are manufactured via electrospinning and characterized using water contact angle measurements, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). Confirmed modified fibers are investigated using in vitro cell culture of NG108-15 neuronal cells and primary Schwann cells to determine cell viability, cell differentiation, and phenotype. CL11-modified fibers significantly support NG108-15 neuronal cell and Schwann cell viability. NG108-15 neuronal cell differentiation maintains Schwann cell phenotype compared to unmodified PCL fiber scaffolds. 3D ex vivo culture of Dorsal root ganglion explants (DRGs) confirms further Schwann cell migration and longer neurite outgrowth from DRG explants cultured on CL11 fiber scaffolds compared to unmodified scaffolds. Thus, a reproducible and cost-effective tool is reported to modify biomaterials with functional amine groups that can significantly improve nerve guidance devices and enhance nerve regeneration.


Assuntos
Silanos , Alicerces Teciduais , Alicerces Teciduais/química , Engenharia Tecidual/métodos , Materiais Biocompatíveis/química , Células de Schwann , Nervos Periféricos , Regeneração Nervosa
10.
Life Sci ; 328: 121871, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37352915

RESUMO

AIMS: Transient receptor potential canonical 5 (TRPC5) channels are redox-sensitive cation-permeable channels involved in temperature and mechanical sensation. Increased expression and over-activation of these channels has been implicated in several central nervous system disorders such as epilepsy, depression, traumatic brain injury, anxiety, Huntington's disease and stroke. TRPC5 channel activation causes increased calcium influx which in turn activates numerous downstream signalling pathways involved in the pathophysiology of neurological disorders. Therefore, we hypothesized that pharmacological blockade and knockdown of TRPC5 channels could attenuate the behavioural deficits and molecular changes seen in CNS disease models such as MPTP/MPP+ induced Parkinson's disease (PD). MATERIALS AND METHODS: In the present study, PD was induced after bilateral intranigral infusion of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to the Sprague Dawley rats. Additionally, SH-SY5Y neurons were exposed to 1-methyl-4-phenylpyridinium (MPP+) to further determine the role of TRPC5 channels in PD. KEY FINDINGS: We used clemizole hydrochloride, a potent TRPC5 channel blocker, to reverse the behavioural deficits, molecular changes and biochemical parameters in MPTP/MPP+-induced PD. Furthermore, knockdown of TRPC5 expression using siRNA also closely phenocopies these effects. We further observed restoration of tyrosine hydroxylase levels and improved mitochondrial health following clemizole treatment and TRPC5 knockdown. These changes were accompanied by diminished calcium influx, reduced levels of reactive oxygen species and decreased apoptotic signalling in the PD models. SIGNIFICANCE: These findings collectively suggest that increased expression of TRPC5 channels is a potential risk factor for PD and opens a new therapeutic window for the development of pharmacological agents targeting neurodegeneration and PD.


Assuntos
Neuroblastoma , Doença de Parkinson , Canais de Potencial de Receptor Transitório , Animais , Humanos , Ratos , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , 1-Metil-4-fenilpiridínio , Cálcio/metabolismo , Neurônios Dopaminérgicos , Neuroblastoma/metabolismo , Oxirredução , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Ratos Sprague-Dawley , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo
11.
Protein Pept Lett ; 30(5): 361-366, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36880185

RESUMO

BACKGROUND: α-Synuclein, a natively disordered protein, is a key component of Lewy bodies, the ubiquitinated protein aggregates which are the pathological hallmark of Parkinson's disease (PD). Meclofenoxate (centrophenoxine) is a nootropic drug which has shown beneficial therapeutic effects in various neuronal diseases. Administration of meclofenoxate enhanced levels of dopamine and improved motor function in animal models of Parkinson's disease (PD). Evidence suggested that dopamine interacts with and modulates α-synuclein aggregation. OBJECTIVE: The aim of this work was to investigate whether the observed positive effect of addition of meclofenoxate, a nootropic agent, on dopamine level, could be correlated with its effect on aggregation of α-synuclein. METHODS: Purification of recombinant human α-synuclein was performed by anion exchange chromatography. The purified protein was incubated in the absence and presence of meclofenoxate and was analyzed for aggregation by Thioflavin T fluorescence spectroscopy. Conformational changes in α-synuclein were monitored by fluorescence spectroscopy and fluorescence quenching studies using a neutral quencher. Secondary structure analysis of α-synuclein was monitored by circular dichroism spectroscopy. RESULTS: Recombinant human α-synuclein was expressed and purified by anion-exchange chromatography. Incubation of α-synuclein with meclofenoxate led to lowering aggregation in a concentration-dependent manner. Reduction in formation of oligomers was seen which suggested the formation of an off-pathway species which did not give rise to an aggregation-competent entity. Fluorescence quenching studies revealed that the additive distorted the native conformation of α- synuclein, leading to the formation of lower amounts of aggregation-prone species. CONCLUSION: In the presence of higher concentrations of meclofenoxate, α-synuclein undergoes a change in its conformation. This change is not dependent on the concentration of the additive. This non-native conformer promotes the formation of a species which does not undergo further aggregation. Our study provides a mechanistic explanation of the earlier observation that meclofenoxate has a beneficial effect on progression of PD in animal models.


Assuntos
Meclofenoxate , Doença de Parkinson , alfa-Sinucleína , Animais , Humanos , alfa-Sinucleína/química , Dopamina/metabolismo , Meclofenoxate/farmacologia , Doença de Parkinson/metabolismo , Agregados Proteicos
12.
ACS Biomater Sci Eng ; 9(3): 1472-1485, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36848250

RESUMO

The use of nerve guidance conduits (NGCs) to treat peripheral nerve injuries is a favorable approach to the current "gold standard" of autografting. However, as simple hollow tubes, they lack specific topographical and mechanical guidance cues present in nerve grafts and therefore are not suitable for treating large gap injuries (30-50 mm). The incorporation of intraluminal guidance scaffolds, such as aligned fibers, has been shown to increase neuronal cell neurite outgrowth and Schwann cell migration distances. A novel blend of PHAs, P(3HO)/P(3HB) (50:50), was investigated for its potential as an intraluminal aligned fiber guidance scaffold. Aligned fibers of 5 and 8 µm diameter were manufactured by electrospinning and characterized using SEM. Fibers were investigated for their effect on neuronal cell differentiation, Schwann cell phenotype, and cell viability in vitro. Overall, P(3HO)/P(3HB) (50:50) fibers supported higher neuronal and Schwann cell adhesion compared to PCL fibers. The 5 µm PHA blend fibers also supported significantly higher DRG neurite outgrowth and Schwann cell migration distance using a 3D ex vivo nerve injury model.


Assuntos
Traumatismos dos Nervos Periféricos , Traumatismos dos Nervos Periféricos/terapia , Células de Schwann/citologia , Adesão Celular , Poli-Hidroxialcanoatos/química , Elétrons , Animais , Camundongos , Células Cultivadas , Movimento Celular
13.
FEBS J ; 290(12): 3270-3289, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36757110

RESUMO

Inhibition of endoribonuclease/kinase Ire1 has shown beneficial effects in many proteotoxicity-induced pathology models. The mechanism by which this occurs has not been elucidated completely. Using a proteotoxic yeast model of Huntington's disease, we show that the deletion of Ire1 led to lower protein aggregation at longer time points. The rate of protein degradation was higher in ΔIre1 cells. We monitored the two major protein degradation mechanisms in the cell. The increase in expression of Rpn4, coding for the transcription factor controlling proteasome biogenesis, was higher in ΔIre1 cells. The chymotrypsin-like proteasomal activity was also significantly enhanced in these cells at later time points of aggregation. The gene and protein expression levels of the autophagy gene Atg8 were higher in ΔIre1 than in wild-type cells. Significant increase in autophagy flux was also seen in ΔIre1 cells at later time points of aggregation. The results suggest that the deletion of Ire1 activates UPR-independent arms of the proteostasis network, especially under conditions of aggravated stress. Thus, the inhibition of Ire1 may regulate UPR-independent cellular stress-response pathways under prolonged stress.


Assuntos
Autofagia , Estresse Proteotóxico , Autofagia/genética , Fatores de Transcrição/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Estresse do Retículo Endoplasmático/genética , Resposta a Proteínas não Dobradas
14.
J Funct Biomater ; 14(1)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36662087

RESUMO

In the last few decades Additive Manufacturing has advanced and is becoming important for biomedical applications. In this study we look at a variety of biomedical devices including, bone implants, tooth implants, osteochondral tissue repair patches, general tissue repair patches, nerve guidance conduits (NGCs) and coronary artery stents to which fused deposition modelling (FDM) can be applied. We have proposed CAD designs for these devices and employed a cost-effective 3D printer to fabricate proof-of-concept prototypes. We highlight issues with current CAD design and slicing and suggest optimisations of more complex designs targeted towards biomedical applications. We demonstrate the ability to print patient specific implants from real CT scans and reconstruct missing structures by means of mirroring and mesh mixing. A blend of Polyhydroxyalkanoates (PHAs), a family of biocompatible and bioresorbable natural polymers and Poly(L-lactic acid) (PLLA), a known bioresorbable medical polymer is used. Our characterisation of the PLA/PHA filament suggest that its tensile properties might be useful to applications such as stents, NGCs, and bone scaffolds. In addition to this, the proof-of-concept work for other applications shows that FDM is very useful for a large variety of other soft tissue applications, however other more elastomeric MCL-PHAs need to be used.

15.
Int J Mol Sci ; 24(2)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36674505

RESUMO

Cellulose of bacterial origin, known as bacterial cellulose (BC), is one of the most versatile biomaterials that has a huge potential in tissue engineering due to its favourable mechanical properties, high hydrophilicity, crystallinity, and purity. Additional properties such as porous nano-fibrillar 3D structure and a high degree of polymerisation of BC mimic the properties of the native extracellular matrix (ECM), making it an excellent material for the fabrication of composite scaffolds suitable for cell growth and tissue development. Recently, the fabrication of BC-based scaffolds, including composites and blends with nanomaterials, and other biocompatible polymers has received particular attention owing to their desirable properties for tissue engineering. These have proven to be promising advanced materials in hard and soft tissue engineering. This review presents the latest state-of-the-art modified/functionalised BC-based composites and blends as advanced materials in tissue engineering. Their applicability as an ideal biomaterial in targeted tissue repair including bone, cartilage, vascular, skin, nerve, and cardiac tissue has been discussed. Additionally, this review briefly summarises the latest updates on the production strategies and characterisation of BC and its composites and blends. Finally, the challenges in the future development and the direction of future research are also discussed.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual , Materiais Biocompatíveis/química , Celulose/química , Alicerces Teciduais/química , Polímeros , Bactérias/química
16.
Biosci Rep ; 43(2)2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36630532

RESUMO

Nanotechnology is an interdisciplinary domain of science, technology and engineering that deals with nano-sized materials/particles. Usually, the size of nanoparticles lies between 1 and 100 nm. Due to their small size and large surface area-to-volume ratio, nanoparticles exhibit high reactivity, greater stability and adsorption capacity. These important physicochemical properties attract scientific community to utilize them in biomedical field. Various types of nanoparticles (inorganic and organic) have broad applications in medical field ranging from imaging to gene therapy. These are also effective drug carriers. In recent times, nanoparticles are utilized to circumvent different treatment limitations. For example, the ability of nanoparticles to cross the blood-brain barrier and having a certain degree of specificity towards amyloid deposits makes themselves important candidates for the treatment of Alzheimer's disease. Furthermore, nanotechnology has been used extensively to overcome several pertinent issues like drug-resistance phenomenon, side effects of conventional drugs and targeted drug delivery issue in leprosy, tuberculosis and cancer. Thus, in this review, the application of different nanoparticles for the treatment of these four important diseases (Alzheimer's disease, tuberculosis, leprosy and cancer) as well as for the effective delivery of drugs used in these diseases has been presented systematically. Although nanoformulations have many advantages over traditional therapeutics for treating these diseases, nanotoxicity is a major concern that has been discussed subsequently. Lastly, we have presented the promising future prospective of nanoparticles as alternative therapeutics. In that section, we have discussed about the futuristic approach(es) that could provide promising candidate(s) for the treatment of these four diseases.


Assuntos
Doença de Alzheimer , Hanseníase , Nanopartículas , Neoplasias , Tuberculose , Humanos , Peptídeos beta-Amiloides , Doença de Alzheimer/tratamento farmacológico , Nanopartículas/química , Portadores de Fármacos , Neoplasias/tratamento farmacológico
17.
ACS Chem Neurosci ; 13(18): 2728-2742, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36094343

RESUMO

Transient receptor potential canonical 5 (TRPC5) channels are predominantly expressed in the striatum and substantia nigra of the brain. These channels are permeable to calcium ions and are activated by oxidative stress. The physiological involvement of TRPC5 channels in temperature and mechanical sensation is well documented; however, evidence for their involvement in the pathophysiology of neurodegenerative disorders like Parkinson's disease (PD) is sparse. Thus, in the present study, the role of TRPC5 channels and their associated downstream signaling was elucidated in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/1-methyl-4-phenylpyridinium (MPTP/MPP+) model of PD. Bilateral intranigral administration of MPTP and 24 h MPP+ exposure were performed to induce PD in the Sprague-Dawley rats and SH-SY5Y cells, respectively. MPTP led to behavioral anomalies and TRPC5 overexpression accompanied by increased calcium influx, apoptosis, oxidative stress, and mitochondrial dysfunctions. In addition, tyrosine hydroxylase (TH) expression was significantly lower in the midbrain and substantia nigra compared to sham animals. Intraperitoneal administration of potent and selective TRPC5 inhibitor, HC070 (0.1 and 0.3 mg/kg) reversed the cognitive and motor deficits seen in MPTP-lesioned rats. It also restored the TH and TRPC5 expression both in the striatum and midbrain. Furthermore, in vitro and in vivo studies suggested improvements in mitochondrial health along with reduced oxidative stress, apoptosis, and calcium-mediated excitotoxicity. Together, these results showed that inhibition of TRPC5 channels plays a crucial part in the reversal of pathology in the MPTP/MPP+ model of Parkinson's disease.


Assuntos
Intoxicação por MPTP , Neuroblastoma , Fármacos Neuroprotetores , Doença de Parkinson , Canais de Potencial de Receptor Transitório , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , 1-Metil-4-fenilpiridínio/toxicidade , Animais , Cálcio/metabolismo , Modelos Animais de Doenças , Humanos , Intoxicação por MPTP/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/metabolismo , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPC , Tirosina 3-Mono-Oxigenase/metabolismo
18.
Appl Microbiol Biotechnol ; 106(18): 6169-6180, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35945363

RESUMO

In response to osmotic shock, the components of high-osmolarity glycerol (HOG) pathway regulate the level of intracellular glycerol in yeast and ensure cell survival. Glycerol is a compatible solute and a stabiliser of proteins. Its role in maintaining proteostasis is less explored. We show that mild stress in the form of dietary restriction leads to increased glycerol level which increases cell viability. However, dietary restriction coupled with protein aggregation decreases intracellular glycerol level and attenuates cell viability. The transcript level of FPS1, the glycerol transporter channel, remains unchanged. However, its activity is altered under enhanced proteotoxic stress. Our results provide evidence for a probable role of the Fps1p channel in the cellular proteostasis network. KEY POINTS: • Dietary restriction led to increased accumulation of glycerol in Fps1-deleted yeast cells. • This led to lower protein aggregation in these cells. • Increased production of glycerol under dietary restriction was not linked to increased level of Fps1.


Assuntos
Proteínas de Membrana , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Glicerol/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Pressão Osmótica , Agregados Proteicos , Proteostase , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
19.
Cancers (Basel) ; 14(14)2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35884609

RESUMO

Tumour cells are shown to change shape and lose polarity when they are cultured in 3D, a feature typically associated with tumour progression in vivo, thus making it significant to study cancer cells in an environment that mimics the in vivo milieu. In this study we established hard (MCF7 and MDA-MB-231, breast cancer) and soft (HCT116, colon cancer) 3D cancer tumour models utilizing a blend of P(3HO-co-3HD) and P(3HB). P(3HO-co-3HD) and P(3HB) belong to a group of natural biodegradable polyesters, PHAs, that are synthesised by microorganisms. The 3D PHA scaffolds produced, with a pore size of 30 to 300 µm, allow for nutrients to diffuse within the scaffold and provide the cells with the flexibility to distribute evenly within the scaffold and grow within the pores. Interestingly, by Day 5, MDA-MB-231 showed dispersed growth in clusters, and MCF7 cells formed an evenly dispersed dense layer, while HCT116 formed large colonies within the pockets of the 3D PHA scaffolds. Our results show Epithelial Mesenchymal Transition (EMT) marker gene expression profiles in the hard tumour cancer models. In the 3D-based PHA scaffolds, MDA-MB-231 cells expressed higher levels of Wnt-11 and mesenchymal markers, such as Snail and its downstream gene Vim mRNAs, while MCF7 cells exhibited no change in their expression. On the other hand, MCF7 cells exhibited a significantly increased E-Cadherin expression as compared to MDA-MB-231 cells. The expression levels of EMT markers were comparative to their expression reported in the tumour samples, making them good representative of cancer models. In future these models will be helpful in mimicking hypoxic tumours, in studying gene expression, cellular signalling, angiogenesis and drug response more accurately than 2D and perhaps other 3D models.

20.
Front Mol Biosci ; 9: 844826, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252358

RESUMO

Adenosine triphosphate (ATP) is an important fuel of life for humans and Mycobacterium species. Its potential role in modulating cellular functions and implications in systemic, pulmonary, and ocular diseases is well studied. Plasma ATP has been used as a diagnostic and prognostic biomarker owing to its close association with disease's progression. Several stresses induce altered ATP generation, causing disorders and illnesses. Small heat shock proteins (sHSPs) are dynamic oligomers that are dominantly ß-sheet in nature. Some important functions that they exhibit include preventing protein aggregation, enabling protein refolding, conferring thermotolerance to cells, and exhibiting anti-apoptotic functions. Expression and functions of sHSPs in humans are closely associated with several diseases like cataracts, cardiovascular diseases, renal diseases, cancer, etc. Additionally, there are some mycobacterial sHSPs like Mycobacterium leprae HSP18 and Mycobacterium tuberculosis HSP16.3, whose molecular chaperone functions are implicated in the growth and survival of pathogens in host species. As both ATP and sHSPs, remain closely associated with several human diseases and survival of bacterial pathogens in the host, therefore substantial research has been conducted to elucidate ATP-sHSP interaction. In this mini review, the impact of ATP on the structure and function of human and mycobacterial sHSPs is discussed. Additionally, how such interactions can influence the onset of several human diseases is also discussed.

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