Biology subjects

Bukhari, H.

Publications and source records attributed to Bukhari, H..

5 recordsLinked to original sources

bioRxiv2024

A systems-biology approach connects aging mechanisms with Alzheimer's disease pathogenesis

Despite years of intense investigation, the mechanisms underlying neuronal death in Alzheimers disease, the most common neurodegenerative disorder, remain incompletely understood. To define relevant pathways, we integrated the results of an unbiased, genome-scale forward genetic screen for age-associated neurodegeneration in Drosophila with human and Drosophila Alzheimers disease-associated multi-omics. We measured proteomics, phosphoproteomics, and metabolomics in Drosophila models of Alzheimers disease and identified Alzheimers disease human genetic variants that modify expression in disease-vulnerable neurons. We used a network optimization approach to integrate these data with previously published Alzheimers disease multi-omic data. We computationally predicted and experimentally demonstrated how HNRNPA2B1 and MEPCE enhance tau-mediated neurotoxicity. Furthermore, we demonstrated that the screen hits CSNK2A1 and NOTCH1 regulate DNA damage in Drosophila and human iPSC-derived neural progenitor cells. Our work identifies candidate pathways that could be targeted to ameliorate neurodegeneration in Alzheimers disease.

systems biology↗

bioRxiv2024

Transcriptional programs mediating neuronal toxicity and altered glial-neuronal signaling in a Drosophila knock-in tauopathy model

Missense mutations in the gene encoding the microtubule-associated protein tau cause autosomal dominant forms of frontotemporal dementia. Multiple models of frontotemporal dementia based on transgenic expression of human tau in experimental model organisms, including Drosophila, have been described. These models replicate key features of the human disease, but do not faithfully recreate the genetic context of the human disorder. Here we use CRISPR-Cas mediated gene editing to model frontotemporal dementia caused by the tau P301L mutation by creating the orthologous mutation, P251L, in the endogenous Drosophila tau gene. Flies heterozygous or homozygous for tau P251L display age-dependent neurodegeneration, metabolic defects and accumulate DNA damage in affected neurons. To understand the molecular events promoting neuronal dysfunction and death in knock-in flies we performed single-cell RNA sequencing on approximately 130,000 cells from brains of tau P251L mutant and control flies. We found that expression of disease-associated mutant tau altered gene expression cell autonomously in all neuronal cell types identified and non-cell autonomously in glial cells. Cell signaling pathways, including glial-neuronal signaling, were broadly dysregulated as were brain region and cell-type specific protein interaction networks and gene regulatory programs. In summary, we present here a genetic model of tauopathy, which faithfully recapitulates the genetic context and phenotypic features of the human disease and use the results of comprehensive single cell sequencing analysis to outline pathways of neurotoxicity and highlight the role of non-cell autonomous changes in glia.

neuroscience↗

bioRxiv2023

Targeting NGF but not VEGF or BDNF signaling reduces endometriosis-associated pain in mice

IntroductionEndometriosis is a chronic inflammatory disease that affects [~]10% of women. A significant fraction of patients experience limited or no efficacy with current therapies. Tissue adjacent to endometriosis lesions often exhibits increased neurite and vascular density, suggesting that disease pathology involves neurotrophic activity and angiogenesis. ObjectivesWe aim to evaluate the potential for key tyrosine-kinase-receptor-coupled neurotrophic molecules to contribute to endometriosis-associated pain in mice. MethodsThe levels of VEGFR1 regulators (VEGFA, VEGFB, PLGF, and sVEGFR1) were quantified by ELISA in peritoneal fluid from endometriosis patients undergoing surgery and used to calculate VEGFR1 occupancy. We used genetic depletion, neutralizing antibody, and pharmacological approaches to specifically block ligand (NGF or BDNF) or neurotrophic receptor (VEGFR1, TRKs) in a murine model of endometriosis-associated pain. Endometriosis-associated pain was determined using the von Frey filaments method, quantification of spontaneous abdominal pain-related behavior, and thermal discomfort. Diseases parameters were evaluated by lesion size and prevalence. ResultsWe found that entrectinib (pan-Trk inhibitor) or anti-NGF treatments reduced evoked pain, spontaneous pain, and thermal discomfort. In contrast, even though receptor occupancy revealing that VEGFR1 agonist levels are sufficient to support pain, blocking VEGFR1 signaling via antibody or tamoxifen-induced knockout did not reduce pain or lesion size in mice. Targeting BDNF-TrkB with an anti-BDNF antibody also proved ineffective. ConclusionsThis suggests NGF-TrkA signaling, but not BDNF-TrkB or VEGF-VEGFR1, mediates endometriosis-associated pain. Moreover, entrectinib blocks endometriosis-associated pain and reduces lesion sizes. Our results also indicated that entrectinib-like molecules are promising candidates for endometriosis treatment. Credit author statementConceptualization: T.H. Zaninelli, V. Fattori, and M.S. Rogers; investigation and data curation: T.H. Zaninelli, V. Fattori, O.K. Heintz, K.R. Wright; A.C. Andrello, W.A. Verri Jr, M.S. Rogers; funding acquisition: M.S. Rogers,, S.A. Missmer, R.M. Anchan; methodology: T.H. Zaninelli, V. Fattori, and M.S. Rogers; human sample collection: S.A. Missmer, A.F. Vitonis, K.L. Terry, R.M. Anchan; animal breading and VEGFR1 ablation: D. Sim and H. Bukhari; resources: A.C. Andrello; D. Bree, T. Zheng, J. Wagner, W.A. Verri Jr, and M.S. Rogers; project administration: T.H. Zaninelli; supervision: V. Fattori, W.A. Verri Jr, and M.S. Rogers; visualization: T.H. Zaninelli, V. Fattori, W.A. Verri Jr, and M.S. Rogers; writing-original draft: T.H. Zaninelli; writing - editing and reviewing: all authors. All authors have read and approved the final version of the manuscript.

pharmacology and toxicology↗

bioRxiv2023

Integrative analysis reveals a conserved role for the amyloid precursor protein in proteostasis during aging

A{beta} peptides derived from the amyloid precursor protein (APP) have been strongly implicated in the pathogenesis of Alzheimers disease. However, the normal function of APP and the importance of that role in neurodegenerative disease is less clear. We recovered the Drosophila ortholog of APP, Appl, in an unbiased forward genetic screen for neurodegeneration mutants. We performed comprehensive single cell transcriptional and proteomic studies of Appl mutant flies to investigate Appl function in the aging brain. We found an unexpected role for Appl in control of multiple cellular pathways, including translation, mitochondrial function, nucleic acid and lipid metabolism, cellular signaling and proteostasis. We mechanistically defined a role for Appl in regulating autophagy through TGF{beta} signaling and documented the broader relevance of our findings using mouse genetic, human iPSC and in vivo tauopathy models. Our results demonstrate a conserved role for APP in controlling age-dependent proteostasis with plausible relevance to Alzheimers disease.

neuroscience↗

bioRxiv2023

A Drosophila model of chemotherapy-related cognitive impairment

Chemotherapy-related cognitive impairment (CRCI) is a common adverse effect of treatment and is characterized by deficits involving multiple cognitive domains including memory. Despite the significant morbidity of CRCI and the expected increase in cancer survivors over the coming decades, the pathophysiology of CRCI remains incompletely understood, highlighting the need for new model systems to study CRCI. Given the powerful array of genetic approaches and facile high throughput screening ability in Drosophila, our goal was to validate a Drosophila model of CRCI. We administered the chemotherapeutic agents cisplatin, cyclophosphamide, and doxorubicin to adult Drosophila. Neurocognitive deficits were observed with all tested chemotherapies, especially cisplatin. We then performed histologic and immunohistochemical analysis of cisplatin-treated Drosophila tissue, demonstrating neuropathologic evidence of increased neurodegeneration, DNA damage, and oxidative stress. Thus, our Drosophila model of CRCI recapitulates clinical, radiologic, and histologic alterations reported in chemotherapy patients. Our new Drosophila model can be used for mechanistic dissection of pathways contributing to CRCI and pharmacologic screens to identify novel therapies to ameliorate CRCI. Summary StatementWe present a Drosophila model of chemotherapy-related cognitive impairment, which recapitulates neurocognitive and neuropathologic changes observed in cancer patients treated with chemotherapy.

animal behavior and cognition↗