scholarly journals Selective targeting of the TLR2/MyD88/NF-κB pathway reduces α-synuclein spreading in vitro and in vivo

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Debashis Dutta ◽  
Malabendu Jana ◽  
Moumita Majumder ◽  
Susanta Mondal ◽  
Avik Roy ◽  
...  

AbstractPathways to control the spreading of α-synuclein (α-syn) and associated neuropathology in Parkinson’s disease (PD), multiple system atrophy (MSA) and dementia with Lewy bodies (DLB) are unclear. Here, we show that preformed α-syn fibrils (PFF) increase the association between TLR2 and MyD88, resulting in microglial activation. The TLR2-interaction domain of MyD88 (wtTIDM) peptide-mediated selective inhibition of TLR2 reduces PFF-induced microglial inflammation in vitro. In PFF-seeded A53T mice, the nasal administration of the wtTIDM peptide, NEMO-binding domain (wtNBD) peptide, or genetic deletion of TLR2 reduces glial inflammation, decreases α-syn spreading, and protects dopaminergic neurons by inhibiting NF-κB. In summary, α-syn spreading depends on the TLR2/MyD88/NF-κB pathway and it can be reduced by nasal delivery of wtTIDM and wtNBD peptides.

2020 ◽  
Vol 70 (3) ◽  
pp. 411-422 ◽  
Author(s):  
Fugen Gu ◽  
Huimin Fan ◽  
Zhixin Cong ◽  
Shuang Li ◽  
Yi Wang ◽  
...  

AbstractDonepezil hydrochloride thermosensitive in situ gel for nasal delivery was prepared by using Poloxamer 407 and Poloxamer 188 as thermoreversible polymers, hydroxypropyl-β-cyclodextrin and ethylparaben as permeation enhancer and preservative, respectively. The gelation temperature and time, pH value of the gel formulation were found to meet the requirements for nasal administration. The in vitro erosion and in vitro release tests exhibited obvious drug sustained release behavior. Meantime, main pharmacokinetic parameters such as tmax, cmax and AUC in plasma as well as in brain were significantly different between the nasal gel formulation and intragastric drug solution in rats (p < 0.01). The relative bioavailability and drug targeting efficiency of the gel formulation were calculated to be 385.6 and 151.2 %, respectively. Thus, the drug gel formulation might be a potential new delivery system for treatment of Alzheimer’s disease due to its higher bioavailability and better distribution to brain when compared to oral route.


2021 ◽  
Author(s):  
Maryna Psol ◽  
Sofia Guerin Darvas ◽  
Kristian Leite ◽  
Sameehan U Mahajani ◽  
Mathias Bähr ◽  
...  

Abstract ß-Synuclein (ß-Syn) has long been considered to be an attenuator for the neuropathological effects caused by the Parkinson’s disease-related α-Synuclein (α-Syn) protein. However, recent studies demonstrated that overabundant ß-Syn can form aggregates and induce neurodegeneration in CNS neurons in vitro and in vivo, albeit at a slower pace as compared to α-Syn. Here we demonstrate that ß-Syn mutants V70M, detected in a sporadic case of Dementia with Lewy Bodies (DLB), and P123H, detected in a familial case of DLB, robustly aggravate the neurotoxic potential of ß-Syn. Intriguingly, the two mutations trigger mutually exclusive pathways. ß-Syn V70M enhances morphological mitochondrial deterioration and degeneration of dopaminergic and non-dopaminergic neurons, but has no influence on neuronal network activity. Conversely, ß-Syn P123H silences neuronal network activity, but does not aggravate neurodegeneration. ß-Syn WT, V70M and P123H formed proteinase K (PK) resistant intracellular fibrils within neurons, albeit with less stable C-termini as compared to α-Syn. Under cell free conditions, ß-Syn V70M demonstrated a much slower pace of fibril formation as compared to WT ß-Syn, and P123H fibrils present with a unique phenotype characterized by large numbers of short, truncated fibrils. Thus, it is possible that V70M and P123H cause structural alterations in ß-Syn, that are linked to their distinct neuropathological profiles. The extent of the lesions caused by these neuropathological profiles is almost identical to that of overabundant α-Syn, and thus likely to be directly involved into etiology of DLB. Over all, this study provides insights into distinct disease mechanisms caused by mutations of ß-Syn.


2021 ◽  
Vol 22 (10) ◽  
pp. 5194
Author(s):  
Paola Pontrelli ◽  
Francesca Conserva ◽  
Rossella Menghini ◽  
Michele Rossini ◽  
Alessandra Stasi ◽  
...  

Diabetic nephropathy (DN) is the most frequent cause of end-stage renal disease. Tubulointerstitial accumulation of lysine 63 (K63)-ubiquitinated (Ub) proteins is involved in the progression of DN fibrosis and correlates with urinary miR-27b-3p downregulation. We explored the renoprotective effect of an inhibitor of K63-Ub (NSC697923), alone or in combination with the ACE-inhibitor ramipril, in vitro and in vivo. Proximal tubular epithelial cells and diabetic DBA/2J mice were treated with NSC697923 and/or ramipril. K63-Ub protein accumulation along with α-SMA, collagen I and III, FSP-1, vimentin, p16INK4A expression, SA-α Gal staining, Sirius Red, and PAS staining were measured. Finally, we measured the urinary albumin to creatinine ratio (uACR), and urinary miR-27b-3p expression in mice. NSC697923, both alone and in association with ramipril, in vitro and in vivo inhibited hyperglycemia-induced epithelial to mesenchymal transition by significantly reducing K63-Ub proteins, α-SMA, collagen I, vimentin, FSP-1 expression, and collagen III along with tubulointerstitial and glomerular fibrosis. Treated mice also showed recovery of urinary miR-27b-3p and restored expression of p16INK4A. Moreover, NSC697923 in combination with ramipril demonstrated a trend in the reduction of uACR. In conclusion, we suggest that selective inhibition of K63-Ub, when combined with the conventional treatment with ACE inhibitors, might represent a novel treatment strategy to prevent the progression of fibrosis and proteinuria in diabetic nephropathy and we propose miR-27b-3p as a biomarker of treatment efficacy.


2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1347.2-1347
Author(s):  
S. Y. Ki ◽  
H. Shin ◽  
Y. Lee ◽  
H. R. Bak ◽  
H. Yu ◽  
...  

Background:Janus kinases (JAK1, JAK2, JAK3, and TYK2) play critical roles in mediating various cytokine signaling, and has been developed as a target for autoimmune diseases such as RA. Tofacitinib, oral Pan-JAK inhibitor, demonstrated efficacy in RA patients, but its widespread use is limited by safety issues. Baricitinib, JAK1/2 inhibitor, is also known to interfere with the hematopoiesis system, such as anemia and thrombocytopenia associated with suppression of JAK2 signals. Therefore, it is necessary to develop a new potent compound that selectively inhibits JAK1 over JAK2, 3Objectives:To identify the pharmacological characteristic based on efficacy of CJ-15314 as potent and selective JAK1 inhibitor for treatment of autoimmune disease.Methods:In vitro, cell-based, kinase panel, Kd value and human whole blood assay were performed to determine the inhibition potency and selectivity for JAK subfamily kinases. In vivo therapeutic potential was evaluated by RA model including rat Adjuvant-Induced Arthritis (AIA) and collagen-induced arthritic (CIA). To confirm the possibility of further expansion into the autoimmune disease, BioMAP® Diversity PLUS® Panel was performed by discoverX.Results:In vitro assay, CJ-15314 inhibited JAK kinase family in a concentration-dependent manner with IC50 values of 3.8 nM against JAK1, Selectivity for JAK1 over JAK2, 3 was approximately 18, 83 fold greater for CJ-15314. In 1mM ATP condition, CJ-15314 has been confirmed to have the highest JAK1 selectivity over competing drugs, under 1 mM ATP condition that reflects the physiological environment in the body. Similarly, Kd values has also confirmed the selectivity of JAK1, which is 10 fold higher than JAK2, 3. Accordingly, in human whole blood assays, CJ-15314 is 11 fold more potent against IL-6 induced pSTAT1 inhibition through JAK1 (IC50 value: 70 nM) than GM-CSF-induced pSTAT5 inhibition (JAK2) whereas baricitinib and filgotinib exhibited only 2 fold and 7 fold respectively.In vivo efficacy model, CJ-15314 inhibited disease severity scores in a dose dependent manner. In the rat AIA model, CJ-15314 at 30 mg/kg dose showed 95.3% decrease in arthritis activity score, 51.2% in figotinib at 30 mg/kg, 97.7% showed baricitinib at 10 mg/kg. CJ-15314 showed superior anti-arthritic efficacy than filgotinib. CJ-15314 also minimally affected anemia-related parameters but not bricitinib end of the 2-week treatment. In the rat CIA model, like 10 mg/kg of bricitinib, 30 mg/kg of CJ-15314 also has a similar effect, with a significant reduction in histopathological scores.In biomap diversity panel, CJ-15314 inhibited the expression of genes such as MCP-1, VCAM-1, IP-10, IL-8, IL-1, sTNF-α and HLA-DR confirming the possibility of expansion into other diseases beyond arthritis.Conclusion:CJ-15314 is a highly selective JAK1 inhibitor, demonstrates robust efficacy in RA animal model and is good candidate for further development for inflammatory diseases.* CJ-15314 is currently conducting a phase I trial in south Korea.References:[1]Clark JD et al. Discovery and development of Janus kinase (JAK) inhibitors for inflammatory diseases. J Med Chem. 2014; 57(12):5023-38.[2]Burmester GR et al. Emerging cell and cytokine targets in rheumatoid arthritis. Nat Rev Rheumatol. 2014; 10(2):77-88[3]Jean-Baptiste Telliez et al. Discovery of a JAK3-selective inhibitor: functional differentiation of JAK3-selective inhibition over pan-JAK or JAK1-selective inhibition. ACS Chem. Biol., 2016; 11 (12):3442-3451Disclosure of Interests:so young Ki Employee of: CJ healthcare, hyunwoo shin Employee of: CJ healthcare, yelim lee Employee of: CJ healthcare, Hyoung rok Bak Employee of: CJ healthcare, hana yu Employee of: CJ healthcare, Seung Chan Kim Employee of: CJ healthcare, juhyun lee Employee of: CJ healthcare, donghyun kim Employee of: CJ healthcare, Dong-hyun Ko Employee of: CJ Healthcare, dongkyu kim Employee of: CJ healthcare


2021 ◽  
Vol 11 (5) ◽  
pp. 336
Author(s):  
Mohammed Ghiboub ◽  
Ahmed M. I. Elfiky ◽  
Menno P. J. de Winther ◽  
Nicola R. Harker ◽  
David F. Tough ◽  
...  

Histone deacetylases (HDACs) and bromodomain-containing proteins (BCPs) play a key role in chromatin remodeling. Based on their ability to regulate inducible gene expression in the context of inflammation and cancer, HDACs and BCPs have been the focus of drug discovery efforts, and numerous small-molecule inhibitors have been developed. However, dose-limiting toxicities of the first generation of inhibitors, which typically target multiple HDACs or BCPs, have limited translation to the clinic. Over the last decade, an increasing effort has been dedicated to designing class-, isoform-, or domain-specific HDAC or BCP inhibitors, as well as developing strategies for cell-specific targeted drug delivery. Selective inhibition of the epigenetic modulators is helping to elucidate the functions of individual epigenetic proteins and has the potential to yield better and safer therapeutic strategies. In accordance with this idea, several in vitro and in vivo studies have reported the ability of more selective HDAC/BCP inhibitors to recapitulate the beneficial effects of pan-inhibitors with less unwanted adverse events. In this review, we summarize the most recent advances with these strategies, discussing advantages and limitations of these approaches as well as some therapeutic perspectives, focusing on autoimmune and inflammatory diseases.


2006 ◽  
Vol 396 (2) ◽  
pp. 277-285 ◽  
Author(s):  
Chrysoula Panethymitaki ◽  
Paul W. Bowyer ◽  
Helen P. Price ◽  
Robin J. Leatherbarrow ◽  
Katherine A. Brown ◽  
...  

The eukaryotic enzyme NMT (myristoyl-CoA:protein N-myristoyltransferase) has been characterized in a range of species from Saccharomyces cerevisiae to Homo sapiens. NMT is essential for viability in a number of human pathogens, including the fungi Candida albicans and Cryptococcus neoformans, and the parasitic protozoa Leishmania major and Trypanosoma brucei. We have purified the Leishmania and T. brucei NMTs as active recombinant proteins and carried out kinetic analyses with their essential fatty acid donor, myristoyl-CoA and specific peptide substrates. A number of inhibitory compounds that target NMT in fungal species have been tested against the parasite enzymes in vitro and against live parasites in vivo. Two of these compounds inhibit TbNMT with IC50 values of <1 μM and are also active against mammalian parasite stages, with ED50 (the effective dose that allows 50% cell growth) values of 16–66 μM and low toxicity to murine macrophages. These results suggest that targeting NMT could be a valid approach for the development of chemotherapeutic agents against infectious diseases including African sleeping sickness and Nagana.


2000 ◽  
Vol 20 (4) ◽  
pp. 1140-1148 ◽  
Author(s):  
Dae-Won Kim ◽  
Brent H. Cochran

ABSTRACT We have previously shown that TFII-I enhances transcriptional activation of the c-fos promoter through interactions with upstream elements in a signal-dependent manner. Here we demonstrate that activated Ras and RhoA synergize with TFII-I for c-fospromoter activation, whereas dominant-negative Ras and RhoA inhibit these effects of TFII-I. The Mek1 inhibitor, PD98059 abrogates the enhancement of the c-fos promoter by TFII-I, indicating that TFII-I function is dependent on an active mitogen-activated protein (MAP) kinase pathway. Analysis of the TFII-I protein sequence revealed that TFII-I contains a consensus MAP kinase interaction domain (D box). Consistent with this, we have found that TFII-I forms an in vivo complex with extracellular signal-related kinase (ERK). Point mutations within the consensus MAP kinase binding motif of TFII-I inhibit its ability to bind ERK and its ability to enhance the c-fos promoter. Therefore, the D box of TFII-I is required for its activity on the c-fos promoter. Moreover, the interaction between TFII-I and ERK can be regulated. Serum stimulation enhances complex formation between TFII-I and ERK, and dominant-negative Ras abrogates this interaction. In addition, TFII-I can be phosphorylated in vitro by ERK and mutation of consensus MAP kinase substrate sites at serines 627 and 633 impairs the phosphorylation of TFII-I by ERK and its activity on the c-fos promoter. These results suggest that ERK regulates the activity of TFII-I by direct phosphorylation.


2011 ◽  
Vol 109 (suppl_1) ◽  
Author(s):  
Allen M Andres ◽  
Chengqun Huang ◽  
Eric P Ratliff ◽  
Genaro Hernandez ◽  
Pamela Lee ◽  
...  

Autophagy-dependent mitochondrial turnover in response to cellular stress is necessary for maintaining cellular homeostasis. However, the mechanisms that govern the selective targeting of damaged mitochondria are poorly understood. Parkin, an E3 ubiquitin ligase, has been shown to be essential for the selective clearance of damaged mitochondria. Parkin is expressed in the heart, yet its function has not been investigated in the context of cardioprotection. We previously reported that autophagy is required for cardioprotection by ischemic preconditioning (IPC). In the present study, we used simulated ischemia in vitro and IPC in hearts (in vivo and ex vivo) to investigate the role of Parkin in mediating cardioprotection. In HL-1 cells, simulated ischemia induced Parkin translocation to mitochondria and mitochondrial elimination. Mitochondrial loss was blunted in Atg5-deficient cells, revealing the requirement for autophagy in mitochondrial elimination. Consistent with previous reports implicating p62/SQSTM1 in mitophagy, we found that downregulation of p62 attenuated mitophagy and exacerbated cell death in HL-1 cardiomyocytes subjected to simulated ischemia. While wild type mice showed p62 translocation to mitochondria after IPC, Parkin knockout mice exhibited attenuated translocation of p62 to mitochondria. Importantly, ablation of Parkin in mice abolished the cardioprotective effects of IPC. These results reveal for the first time the crucial role of Parkin and mitophagy in cardioprotection.


2004 ◽  
Vol 186 (20) ◽  
pp. 6983-6998 ◽  
Author(s):  
Aneta A. Bartosik ◽  
Krzysztof Lasocki ◽  
Jolanta Mierzejewska ◽  
Christopher M. Thomas ◽  
Grazyna Jagura-Burdzy

ABSTRACT The par genes of Pseudomonas aeruginosa have been studied to increase the understanding of their mechanism of action and role in the bacterial cell. Key properties of the ParB protein have been identified and are associated with different parts of the protein. The ParB- ParB interaction domain was mapped in vivo and in vitro to the C-terminal 56 amino acids (aa); 7 aa at the C terminus play an important role. The dimerization domain of P. aeruginosa ParB is interchangeable with the dimerization domain of KorB from plasmid RK2 (IncP1 group). The C-terminal part of ParB is also involved in ParB-ParA interactions. Purified ParB binds specifically to DNA containing a putative parS sequence based on the consensus sequence found in the chromosomes of Bacillus subtilis, Pseudomonas putida, and Streptomyces coelicolor. The overproduction of ParB was shown to inhibit the function of genes placed near parS. This “silencing” was dependent on the parS sequence and its orientation. The overproduction of P. aeruginosa ParB or its N-terminal part also causes inhibition of the growth of P. aeruginosa and P. putida but not Escherichia coli cells. Since this inhibitory determinant is located well away from ParB segments required for dimerization or interaction with the ParA counterpart, this result may suggest a role for the N terminus of P. aeruginosa ParB in interactions with host cell components.


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