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Chakraborty, I.

Publications and source records attributed to Chakraborty, I..

2 recordsLinked to original sources

Coordination of Anle138b to Silver Results in Selective Reduction of a C-terminal truncated Alpha-synuclein Protein and Increased Aggregate Size

Parkinsons disease (PD) is a prevalent age-related neurodegenerative syndrome, partially thought to be caused by a decrease in alpha-synuclein proteostasis. Anle138b = 5-(1,3-benzodioxol-5-yl)-3-(3-bromophenyl)-1H-pyrazole (HL), is undergoing clinical trials as a promising mitigator of alpha-synuclein aggregation. Because complexation to metals is known to modulate the activity of several drugs, we have prepared and characterized: H2L(ClO4), [CuI({micro}-L)]3, and [AgI({micro}-L)]3. To better understand the bioviability of these compounds, we monitored their effects in a cell culture model of alpha-synuclein protein aggregation using human alpha-synuclein pre-formed fibrils (PFFs). Using two different anti-alpha-synuclein antibodies, our data suggests that [AgI({micro}-L)]3 decreases a C-terminal truncated protein that is approximately 12.4 kDa, as well as increases the size and alters the shape of PFF-induced aggregates. This indicates that [AgI({micro}-L)]3 impacts aggregation in a manner different from HL and may serve as a novel tool for studying C-terminal truncation related aggregation chemistry. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/679869v1_ufig1.gif" ALT="Figure 1"> View larger version (18K): org.highwire.dtl.DTLVardef@4bbda5org.highwire.dtl.DTLVardef@8fc0b7org.highwire.dtl.DTLVardef@1b561f5org.highwire.dtl.DTLVardef@1322902_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

Humanized TfR1 and transferrin gene-replacement rats for in vivo evaluation of BBB transport

The transferrin receptor 1 (TfR1)-transferrin (TF) axis plays a central role in iron homeostasis and has long been recognized as a promising route for delivering biologics across the blood-brain barrier (BBB). We have developed a class of human-specific anti-TfR1 nanobodies (NewroBus) that exploit this transport pathway. However, the lack of cross-reactivity with rodent TfR1 limits the utility of standard animal models for preclinical testing. To overcome this challenge, we generated knock-in (KI) rats in which the coding sequences of the endogenous Tfrc and Tf genes were replaced with human coding sequences, yielding animals that express human TfR1 and/or human TF under physiological control. Rats homozygous for both humanized alleles were viable and fertile, indicating that the human proteins can functionally replace their rodent equivalents. Nonetheless, these double homozygous rats exhibited erythropoietic abnormalities and tissue-specific alterations in iron distribution--characterized by decreased splenic and increased hepatic iron--suggesting incomplete functional compensation. In contrast, heterozygous rats showed only mild, subclinical hematologic changes (microcytosis and hypochromia). These findings demonstrate that the humanized TfR1-TF axis is compatible with life and iron regulation, albeit with varying degrees of compensation depending on gene dosage. Importantly, these KI rats provide a translationally relevant platform for evaluating pharmacokinetics, CNS penetration, and safety of human-specific BBB-targeting therapeutics, including NewroBus-based biologics and other TfR1-mediated delivery strategies.

neuroscience↗