Impairment of autophagy by TTR V30M aggregates: in vivo reversal by TUDCA and curcumin

2016 ◽  
Vol 130 (18) ◽  
pp. 1665-1675 ◽  
Author(s):  
Cristina A. Teixeira ◽  
Maria do Rosário Almeida ◽  
Maria João Saraiva
Keyword(s):  
Cell Culture ◽  
Amyloid Fibrils ◽  
Transgenic Animals ◽  
Cellular Mechanism ◽  
In Vivo Studies ◽  
Autophagic Flux ◽  
Gi Tract ◽  
Alternative Therapeutic Approach

Transthyretin (TTR)-related amyloidoses are diseases characterized by extracellular deposition of amyloid fibrils and aggregates in tissues composed of insoluble misfolded TTR that becomes toxic. Previous studies have demonstrated the ability of small compounds in preventing and reversing TTR V30M deposition in transgenic mice gastrointestinal (GI) tract as well as lowering biomarkers associated with cellular stress and apoptotic mechanisms. In the present study we aimed to study TTR V30M aggregates effect in autophagy, a cellular mechanism crucial for cell survival that has been implicated in the development of several neurodegenerative diseases. We were able to demonstrate in cell culture that TTR V30M aggregates cause a partial impairment of the autophagic machinery as shown by p62 accumulation, whereas early steps of the autophagic flux remain unaffected as shown by autophagosome number evaluation and LC3 turnover assay. Our studies performed in TTR V30M transgenic animals demonstrated that tauroursodeoxycholic acid (TUDCA) and curcumin effectively reverse p62 accumulation in the GI tract pointing to the ability of both compounds to modulate autophagy additionally to mitigate apoptosis. Overall, our in vitro and in vivo studies establish an association between TTR V30M aggregates and autophagy impairment and suggest the use of autophagy modulators as an additional and alternative therapeutic approach for the treatment of TTR V30M-related amyloidosis.

scholarly journals Which cytochrome P450 metabolizes phenazepam? Step by step in silico, in vitro, and in vivo studies

2018 ◽  
Vol 33 (2) ◽  
pp. 65-73 ◽  
Author(s):  
Dmitriy V. Ivashchenko ◽  
Anastasia V. Rudik ◽  
Andrey A. Poloznikov ◽  
Sergey V. Nikulin ◽  
Valeriy V. Smirnov ◽  
...  
Keyword(s):  
Cell Culture ◽  
Cytochrome P450 ◽  
In Silico ◽  
In Vivo Studies ◽  
Cyp3a Activity ◽  
Cell Culture Study ◽  
Study Results ◽  
Three Stages

Abstract Background: Phenazepam (bromdihydrochlorphenylbenzodiazepine) is the original Russian benzodiazepine tranquilizer belonging to 1,4-benzodiazepines. There is still limited knowledge about phenazepam’s metabolic liver pathways and other pharmacokinetic features. Methods: To determine phenazepam’s metabolic pathways, the study was divided into three stages: in silico modeling, in vitro experiment (cell culture study), and in vivo confirmation. In silico modeling was performed on the specialized software PASS and GUSAR to evaluate phenazepam molecule affinity to different cytochromes. The in vitro study was performed using a hepatocytes’ cell culture, cultivated in a microbioreactor to produce cytochrome P450 isoenzymes. The culture medium contained specific cytochrome P450 isoforms inhibitors and substrates (for CYP2C9, CYP3A4, CYP2C19, and CYP2B6) to determine the cytochrome that was responsible for phenazepam’s metabolism. We also measured CYP3A activity using the 6-betahydroxycortisol/cortisol ratio in patients. Results: According to in silico and in vitro analysis results, the most probable metabolizer of phenazepam is CYP3A4. By the in vivo study results, CYP3A activity decreased sufficiently (from 3.8 [95% CI: 2.94–4.65] to 2.79 [95% CI: 2.02–3.55], p=0.017) between the start and finish of treatment in patients who were prescribed just phenazepam. Conclusions: Experimental in silico and in vivo studies confirmed that the original Russian benzodiazepine phenazepam was the substrate of CYP3A4 isoenzyme.

scholarly journals A Review of the Role of Neurotensin and Its Receptors in Colorectal Cancer

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Shengyang Qiu ◽  
Gianluca Pellino ◽  
Francesca Fiorentino ◽  
Shahnawaz Rasheed ◽  
Ara Darzi ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Animal Studies ◽  
In Vivo Studies ◽  
Signalling Pathways ◽  
Diagnostic Biomarker ◽  
Gi Tract ◽  
Cellular Receptors

Neurotensin (NTS) is a physiologically occurring hormone which affects the function of the gastrointestinal (GI) tract. In recent years, NTS, acting through its cellular receptors (NTSR), has been implicated in the carcinogenesis of several cancers. In colorectal cancer (CRC), a significant body of evidence, from in vitro and in vivo studies, is available which elucidates the molecular biology of NTS/NTSR signalling and the resultant growth of CRC cells. There is growing clinical data from human studies which corroborate the role NTS/NTSR plays in the development of human CRC. Furthermore, blockade and modulation of the NTS/NTSR signalling pathways appears to reduce CRC growth in cell cultures and animal studies. Lastly, NTS/NTSR also shows potential of being utilised as a diagnostic biomarker for cancers as well as targets for functional imaging. We summarise the existing evidence and understanding of the role of NTS and its receptors in CRC.

scholarly journals Biomaterial-Assisted Regenerative Medicine

2021 ◽  
Vol 22 (16) ◽  
pp. 8657
Author(s):  
Teruki Nii ◽  
Yoshiki Katayama
Keyword(s):  
Cell Culture ◽  
Regenerative Medicine ◽  
Drug Screening ◽  
Drug Research ◽  
Drug Evaluation ◽  
Cell Activity ◽  
The Body ◽  
In Vivo Studies

This review aims to show case recent regenerative medicine based on biomaterial technologies. Regenerative medicine has arousing substantial interest throughout the world, with “The enhancement of cell activity” one of the essential concepts for the development of regenerative medicine. For example, drug research on drug screening is an important field of regenerative medicine, with the purpose of efficient evaluation of drug effects. It is crucial to enhance cell activity in the body for drug research because the difference in cell condition between in vitro and in vivo leads to a gap in drug evaluation. Biomaterial technology is essential for the further development of regenerative medicine because biomaterials effectively support cell culture or cell transplantation with high cell viability or activity. For example, biomaterial-based cell culture and drug screening could obtain information similar to preclinical or clinical studies. In the case of in vivo studies, biomaterials can assist cell activity, such as natural healing potential, leading to efficient tissue repair of damaged tissue. Therefore, regenerative medicine combined with biomaterials has been noted. For the research of biomaterial-based regenerative medicine, the research objective of regenerative medicine should link to the properties of the biomaterial used in the study. This review introduces regenerative medicine with biomaterial.

scholarly journals Tau Secretion and Propagation Is Regulated by p300/CBP via Autophagy-Lysosomal Pathway in Tauopathy

2018 ◽  
Author(s):  
Xu Chen ◽  
Yaqiao Li ◽  
Chao Wang ◽  
Yinyan Tang ◽  
Sue-Ann Mok ◽  
...  
Keyword(s):  
Mouse Model ◽  
Transgenic Mouse ◽  
Transgenic Mouse Model ◽  
Cellular Mechanism ◽  
Autophagic Flux ◽  
Impaired Function ◽  
Unconventional Secretion ◽  
Lysine Acetyltransferase

SUMMARYThe trans-neuronal propagation of tau has been implicated in the progression of tau-mediated neurodegeneration. Tau secretion from neurons is the first step in tau transmission, but little is known about the cellular mechanism. Here, we report that p300/CBP, the lysine acetyltransferase that acetylates tau and regulates its homeostasis and toxicity, serves as a key regulator of tau secretion by inhibiting the autophagy-lysosomal pathway (ALP). Increased p300/CBP activity was associated with impaired function of this pathway in a tau transgenic mouse model. p300/CBP hyperactivation increased tau secretion by blocking autophagic flux. Conversely, inhibiting p300/CBP genetically or pharmacologically promoted autophagic flux, and reduced tau accumulation, tau secretion, and tau propagation in fibril-induced tau spreading models in vitro and in vivo. Our findings show that p300/CBP-induced impairment in the ALP underlies excessive unconventional secretion and pathogenic spread of tau.

scholarly journals Characterization of the Prion Protein Binding Properties of Antisense Oligonucleotides

Biomolecules ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 1 ◽  
Author(s):  
Andrew G. Reidenbach ◽  
Eric Vallabh Minikel ◽  
Hien T. Zhao ◽  
Stacy G. Guzman ◽  
Alison J. Leed ◽  
...  
Keyword(s):  
Cell Culture ◽  
Prion Protein ◽  
Isothermal Titration Calorimetry ◽  
Prion Disease ◽  
Antisense Oligonucleotides ◽  
In Vivo Studies ◽  
Titration Calorimetry ◽  
Independent Manner

Antisense oligonucleotides (ASOs) designed to lower prion protein (PrP) expression in the brain through RNase H1-mediated degradation of PrP RNA are in development as prion disease therapeutics. ASOs were previously reported to sequence-independently interact with PrP and inhibit prion accumulation in cell culture, yet in vivo studies using a new generation of ASOs found that only PrP-lowering sequences were effective at extending survival. Cerebrospinal fluid (CSF) PrP has been proposed as a pharmacodynamic biomarker for trials of such ASOs, but is only interpretable if PrP lowering is indeed the relevant mechanism of action in vivo and if measurement of PrP is unconfounded by any PrP–ASO interaction. Here, we examine the PrP-binding and antiprion properties of ASOs in vitro and in cell culture. Binding parameters determined by isothermal titration calorimetry were similar across all ASOs tested, indicating that ASOs of various chemistries bind full-length recombinant PrP with low- to mid-nanomolar affinity in a sequence-independent manner. Nuclear magnetic resonance, dynamic light scattering, and visual inspection of ASO–PrP mixtures suggested, however, that this interaction is characterized by the formation of large aggregates, a conclusion further supported by the salt dependence of the affinity measured by isothermal titration calorimetry. Sequence-independent inhibition of prion accumulation in cell culture was observed. The inefficacy of non-PrP-lowering ASOs against prion disease in vivo may be because their apparent activity in vitro is an artifact of aggregation, or because the concentration of ASOs in relevant compartments within the central nervous system (CNS) quickly drops below the effective concentration for sequence-independent antiprion activity after bolus dosing into CSF. Measurements of PrP concentration in human CSF were not impacted by the addition of ASO. These findings support the further development of PrP-lowering ASOs and of CSF PrP as a pharmacodynamic biomarker.

scholarly journals Cytotoxicity Studies on Naproxen and Piroxicam Nanoformulations

2020 ◽  
Vol 8 (3) ◽  
pp. 87-94
Author(s):  
Sandeep Patnaik ◽  
K Madhusudhana Rao ◽  
Vijay Sai
Keyword(s):  
Cell Culture ◽  
Cell Viability ◽  
Cultured Cells ◽  
In Vitro Models ◽  
In Vivo Studies ◽  
Tetrazolium Salt ◽  
Mucous Layer ◽  
Cytotoxicity Studies

Caco-2 cells were used as in vitro models to assess the cell viability characteristics of the carriers Soluplus®, Gelucire 50/13 and PVP K25 and the nanoformulations of Naproxen and Piroxicam. The assessment of cell viability was done using the tetrazolium salt based MTT assay. Gelucire 50/13 and its NFs were observed to have slightly higher cytotoxicity than PVP and Soluplus® and their respective NFs. All the NFs were observed to follow the cytotoxicity trend of the polymers. Our results show that no significant decrease in cell viability was seen until 0.01% concentration of Gelucire 50/13 for 12-h exposure. The NFs as well as the polymers alone had no significant effect on the viability of Caco-2 cells below 0.01% concentrations. The intestine has a protective mucous layer, whereas the cell culture monolayers do not. The intestinal tissues also have more capacity to recover from trauma than the cultured cells. Hence the present NFs can be expected to show lesser cytotoxicity when subjected to in vivo studies.  

In vitro and in vivo studies of new cationic Zn(II)‐benzonaphthoporphyrazines as photosensitizers for PDT

2001 ◽  
Vol 5 (8) ◽  
pp. 645-651
Author(s):  
M. Peeva ◽  
M. Shopova ◽  
U. Michelsen ◽  
D. Wöhrle ◽  
G. Petrov ◽  
...  
Keyword(s):  
In Vivo Studies

Effect of caffeine on theophyliine on cerebral blood flow response to brain activation: In vitro and in vivo studies

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S198-S198
Author(s):  
Joseph R Meno ◽  
Thien-son K Nguyen ◽  
Elise M Jensen ◽  
G Alexander West ◽  
Leonid Groysman ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Activation ◽  
In Vivo Studies ◽  
Blood Flow Response ◽  
Flow Response

Effects of Unfractionated and Low Molecular Weight Heparins on Platelet Thromboxane Biosynthesis “In Vivo”

1994 ◽  
Vol 72 (06) ◽  
pp. 942-946 ◽  
Author(s):  
Raffaele Landolfi ◽  
Erica De Candia ◽  
Bianca Rocca ◽  
Giovanni Ciabattoni ◽  
Armando Antinori ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Unfractionated Heparin ◽  
Low Molecular Weight Heparin ◽  
Primary Source ◽  
In Vivo Studies ◽  
Low Molecular Weight ◽  
Heparin Administration ◽  
To Receive

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.

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