Biology subjects

Friedman, R. A.

Publications and source records attributed to Friedman, R. A..

10 recordsLinked to original sources

bioRxiv2024

An Open-Source Deep Learning-Based GUI Toolbox For Automated Auditory Brainstem Response Analyses (ABRA)

Hearing loss is a pervasive global health challenge with profound impacts on communication, cognitive function, and quality of life. Recent studies have established age-related hearing loss as a significant risk factor for dementia, highlighting the importance of hearing loss research. Auditory brainstem responses (ABRs), which are electrophysiological recordings of acoustically evoked synchronized neural activity from the auditory nerve and brainstem, serve as in vivo correlates for sensory hair cell and synaptic function, hearing sensitivity, and other critical readouts of auditory pathway physiology, making them highly valuable for both basic neuroscience and clinical research. Despite their utility, traditional ABR analyses rely heavily on subjective manual interpretation, which may introduce variability and pose challenges for reproducibility across studies. Here, we introduce Auditory Brainstem Response Analyzer (ABRA), a novel suite of open-source ABR analysis tools powered by deep learning, which automates and standardizes ABR waveform analysis. ABRA employs convolutional neural networks trained on diverse datasets collected from multiple experimental settings, achieving rapid and unbiased extraction of key ABR metrics, including peak amplitude, latency, and auditory threshold estimates. We demonstrate that ABRAs deep learning models provide performance comparable to expert human annotators while dramatically reducing analysis time and enhancing reproducibility across datasets from different laboratories. By bridging hearing research, sensory neuroscience, and advanced computational techniques, ABRA facilitates broader interdisciplinary insights into auditory function. An online version of the tool is available for use at no cost at https://abra.ucsd.edu.

neuroscience↗

bioRxiv2024

VASCilia (Vision Analysis StereoCilia): A Napari Plugin for Deep Learning-Based 3D Analysis of Cochlear Hair Cell Stereocilia Bundles

Cochlear hair cells are essential for hearing, and their stereocilia bundles are critical for mechanotransduction. However, analyzing the 3D morphology of these bundles can be challenging due to their complex organization and the presence of other cellular structures in the tissue. To address this, we developed VASCilia (Vision Analysis StereoCilia), a Napari plugin suite that automates the analysis of 3D confocal microscopy datasets of phalloidin-stained cochlear hair cell bundles. VASCilia includes five deep learning-based models that streamline the analysis process, including: (1) Z-Focus Tracker (ZFT) for selecting relevant slices in a 3D image stack; (2) PCPAlignNet (Planar Cell Polarity Alignment Network) for automated orientation of image stacks; (3) a segmentation model for identifying and delineating stereocilia bundles; (4) a tonotopic Position Prediction tool; and (5) a classification tool for identifying hair cell subtypes. In addition, VASCilia provides automated computational tools and measurement capabilities. Using VASCilia, we demonstrate its utility on challenging datasets, including neonatal wildtype and Eps8 KO 5-day old mice), revealing that total actin content does not necessarily scale with bundle height. We further showcase its power by quantifying complex bundle disorganization in Cdh23-/- cochleae via texture analysis, which revealed systematically more heterogeneous and less regular bundles than in controls. These novel biological findings demonstrate the power of VASCilia in facilitating detailed quantitative analysis of stereocilia. VASCilia also provides a user-friendly interface that allows researchers to easily navigate and use the tool, with the added capability to reload all their analyses for review or sharing purposes. We believe that VASCilia will be a valuable resource for researchers studying cochlear hair cell development and function, addressing a longstanding need in the hair cell research community for specialized deep learning-based tools capable of high-throughput image quantitation. We have released our code along with a manually annotated dataset that includes approximately 55 3D stacks featuring instance segmentation (https://github.com/ucsdmanorlab/Napari-VASCilia). This dataset comprises a total of 502 inner and 1,703 outer hair cell bundles annotated in 3D. As the first open-source dataset of its kind, we aim to establish a foundational resource for constructing a comprehensive atlas of cochlea hair cell images. Ultimately, this initiative will support the development of foundational models adaptable to various species, markers, and imaging scales to accelerate advances within the hearing research community.

bioinformatics↗

bioRxiv2024

The CALERIE™ Genomic Data Resource

Caloric restriction (CR) slows biological aging and prolongs healthy lifespan in model organisms. Findings from CALERIE-2 - the first ever randomized, controlled trial of long-term CR in healthy, non-obese humans - broadly supports a similar pattern of effects in humans. To expand our understanding of the molecular pathways and biological processes underpinning CR effects in humans, we generated a series of genomic datasets from stored biospecimens collected from n=218 participants during the trial. These data constitute the first publicly-accessible genomic data resource for a randomized controlled trial of an intervention targeting the biology of aging. Datasets include whole-genome SNP genotypes, and three-timepoint-longitudinal DNA methylation, mRNA, and small RNA datasets generated from blood, skeletal muscle, and adipose tissue samples (total sample n=2327). The CALERIE Genomic Data Resource described in this article is available from the Aging Research Biobank. This multi-tissue, multi-omic, longitudinal data resource has great potential to advance translational geroscience.

genomics↗

bioRxiv2024

An engineered human cardiac tissue model reveals contributions of systemic lupus erythematosus autoantibodies to myocardial injury

Systemic lupus erythematosus (SLE) is a highly heterogenous autoimmune disease that affects multiple organs, including the heart. The mechanisms by which myocardial injury develops in SLE, however, remain poorly understood. Here we engineered human cardiac tissues and cultured them with IgG fractions containing autoantibodies from SLE patients with and without myocardial involvement. We observed unique binding patterns of IgG from two patient subgroups: (i) patients with severe myocardial inflammation exhibited enhanced binding to apoptotic cells within cardiac tissues subjected to stress, and (ii) patients with systolic dysfunction exhibited enhanced binding to the surfaces of viable cardiomyocytes. Functional assays and RNA sequencing (RNA-seq) revealed that IgGs from patients with systolic dysfunction exerted direct effects on engineered tissues in the absence of immune cells, altering tissue cellular composition, respiration and calcium handling. Autoantibody target characterization by phage immunoprecipitation sequencing (PhIP-seq) confirmed distinctive IgG profiles between patient subgroups. By coupling IgG profiling with cell surface protein analyses, we identified four pathogenic autoantibody candidates that may directly alter the function of cells within the myocardium. Taken together, these observations provide insights into the cellular processes of myocardial injury in SLE that have the potential to improve patient risk stratification and inform the development of novel therapeutic strategies.

bioengineering↗

bioRxiv2023

Altered Fhod3 Expression Involved in Progressive High-Frequency Hearing Loss via Dysregulation of Actin Polymerization Stoichiometry in The Cuticular Plate

Age-related hearing loss (ARHL) is a common sensory impairment with complex underlying mechanisms. In our previous study, we performed a meta-analysis of genome-wide association studies (GWAS) in mice and identified a novel locus on chromosome 18 associated with ARHL specifically linked to a 32 kHz tone burst stimulus. Consequently, we investigated the role of Formin Homology 2 Domain Containing 3 (Fhod3), a newly discovered candidate gene for ARHL based on the GWAS results. We observed Fhod3 expression in auditory hair cells (HCs) and primarily localized at the cuticular plate (CP). To understand the functional implications of Fhod3 in the cochlea, we generated Fhod3 overexpression mice (Pax2-Cre+/-; Fhod3Tg/+) (TG) and HC-specific conditional knockout mice (Atoh1-Cre+/-; Fhod3fl/fl) (KO). Audiological assessments in TG mice demonstrated progressive high-frequency hearing loss, characterized by predominant loss of outer hair cells, and a decreased phalloidin intensities of CP. Ultrastructural analysis revealed shortened stereocilia in the basal turn cochlea. Importantly, the hearing and HC phenotype in TG mice were replicated in KO mice. These findings indicate that Fhod3 plays a critical role in regulating actin dynamics in CP and stereocilia. Further investigation of Fhod3 related hearing impairment mechanisms may facilitate the development of therapeutic strategies for ARHL in humans.

neuroscience↗

bioRxiv2023

A pancreatic cancer mouse model with human immunity

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a tumor immune microenvironment (TIME) that promotes resistance to immunotherapy. A preclinical model system that facilitates studies of the TIME and its impact on the responsiveness of human PDAC to immunotherapies remains an unmet need. We report a novel mouse model, which develops metastatic human PDAC that becomes infiltrated by human immune cells recapitulating the TIME of human PDAC. The model may serve as a versatile platform to study the nature of human PDAC TIME and its response to various treatments.

cancer biology↗

bioRxiv2023

Selective loss of specific subsets of hair cell and spiral ganglion cell types in an outbred mouse model of age-related hearing loss

Age-related hearing loss (ARHL) is the most common cause of hearing loss and one of the most prevalent conditions affecting the elderly worldwide. Despite evidence from our lab and others about its polygenic nature, little is known about the specific genes, cell types and pathways involved in ARHL, impeding the development of therapeutic interventions. In this manuscript, we describe, for the first time, the complete cell-type specific transcriptome of the aging mouse cochlea using snRNA-seq in an outbred mouse model in relation to auditory threshold variation. Cochlear cell types were identified using unsupervised clustering and annotated via a three-tiered approach - first by linking to expression of known marker genes, then using the NS-Forest algorithm to select minimum cluster-specific marker genes and reduce dimensional feature space for statistical comparison of our clusters with existing publicly-available data sets on the gEAR website (https://umgear.org/), and finally, by validating and refining the annotations using Multiplexed Error Robust Fluorescence In Situ Hybridization (MERFISH) and the cluster-specific marker genes as probes. We report on 60 unique cell-types expanding the number of defined cochlear cell types by more than two times. Importantly, we show significant specific cell type increases and decreases associated with loss of hearing acuity implicating specific subsets of hair cell subtypes, ganglion cell subtypes, and cell subtypes withing the stria vascularis in this model of ARHL. These results provide a view into the cellular and molecular mechanisms responsible for age-related hearing loss and pathways for therapeutic targeting.

genomics↗

bioRxiv2022

Intestinal myofibroblasts regulate intestinal epithelial cell plasticity via YAP/TAZ

Intestinal stromal cells play a key role as the crypt niche cells during epithelial homeostasis and tumor initiation. However, the underlying cellular and molecular mechanisms remain unclear. We developed various types of three-dimensional (3D) tissue culture models to culture small intestinal myofibroblasts (SI MFs) together with enteroids. SI MFs significantly enhanced self-renewal, lumen formation and survival of enteroids, that was mediated via a paracrine mechanism in a Wnt-independent manner. Such co-cultured enteroids resembled SI organoids derived from Apc+/1638N tumors. Microarray analysis showed upregulation of genes associated with YAP signaling in enteroids co-cultured with SI MFs, which was confirmed by protein quantification by mass spectrometry and could be correlated with findings from human colorectal tumor specimens. Mass spectrometric analysis of conditioned media and inhibitor studies pointed to a role for TGF-{beta} in the SI MF-SI epithelium cross-talk. Altogether, utilizing different 3D stroma-epithelium co-culture models, we demonstrate here that SI MFs have the potential to induce a tumor-like phenotype in the intestinal crypts via a paracrine mechanism, that involves YAP and TGF-{beta}, but not canonical Wnt signaling.

cell biology↗

bioRxiv2019

Targeting MEK5 impairs non-homologous end-joining repair and sensitizes prostate cancer to DNA damaging agents

Radiotherapy is commonly used to treat a variety of solid human tumors, including localized prostate cancer. However, treatment failure often ensues due to tumor intrinsic or acquired radioresistance. Here we find that the MEK5/ERK5 signaling pathway is associated with resistance to genotoxic stress in aggressive prostate cancer cells. MEK5 knockdown by RNA interference sensitizes prostate cancer cells to ionizing radiation (IR) and etoposide treatment, as assessed by clonogenic survival and short-term proliferation assays. Mechanistically, MEK5 downregulation impairs phosphorylation of the catalytic subunit of DNA-PK at serine 2056 in response to IR or etoposide treatment. Although MEK5 knockdown does not influence the initial appearance of radiation- and etoposide-induced {gamma}H2AX and 53BP1 foci, it markedly delays their resolution, indicating a DNA repair defect. A cell-based assay shows that non-homologous end joining (NHEJ) is compromised in cells with ablated MEK5 protein expression. Finally, MEK5 silencing combined with focal irradiation causes strong inhibition of tumor growth in mouse xenografts, compared with MEK5 depletion or radiation alone. These findings reveal a convergence between MEK5 signaling and DNA repair by NHEJ in conferring resistance to genotoxic stress in advanced prostate cancer and suggest targeting MEK5 as an effective therapeutic intervention in the management of this disease.

cancer biology↗

bioRxiv2018

Genome-wide Association Study for Noise-induced Cochlear Synaptopathy.

Article SummaryIn order to elucidate the genetic architecture of the auditory hair cell synapse and the susceptibility to noise-induced cochlear synaptopathy, we are providing the first genome-wide association study with 111 strains (n=695) of the Hybrid Mouse Diversity Panel based upon the strain variation of the wave 1 P1-N1 amplitude of the auditory brainstem responses both before and after noise exposure. Based on this association analysis and our cochlear gene expression data, we identified several novel loci and prioritized positional candidate genes related to cochlear synaptopathy, especially after exposure to noise.\n\nAbstractThis is the first genome-wide association study (GWAS) with the Hybrid Mouse Diversity Panel (HMDP) to define the genetic landscape of the auditory hair cell synapse and the susceptibility to noise-induced cochlear synaptopathy. We tested 5-week old female mice (n=695) from 111 HMDP strains (n= 6-7/strain) at baseline and post noise exposure using ABR wave 1 suprathreshold amplitudes (P1-N1 at 80 dB SPL) at 8, 12, 16, 24 and 32 kHz tone burst stimuli. Mice were exposed for 2 hours to 10 kHz octave band noise (OBN) at 108 dB SPL. A broad range of suprathreshold ABR wave 1 amplitude were detected across the HMDP strains. At the genome-wide significance threshold (-logP = 5.39), associations on Chr. 3 and Chr. 16 were identified at baseline. Also, association peaks on Chr. 2 and Chr. 13 were determined post noise exposure. In order to prioritize candidate genes, we generated gene expression microarray profiles using RNA isolated from cochleae in 64 HMDP strains (n =3 arrays per strain). We then used EMMA to perform an association analysis between all SNPs and array probes mapping within each region. A total of 17 genes (2 within Chr. 3 association, 6 within Chr. 2 association and 9 within Chr. 13 association) of these 3 loci were identified with at least 1 probe whose expression was regulated by a significant cis eQTL in the cochlea. Also, the genetic architecture of noise induced cochlear synaptopathy is distinct from that of baseline auditory nerve/synapse integrity. In summary, from this GWAS and our eQTL data, we identified 4 novel loci and prioritized positional candidate genes related to cochlear synaptopathy at baseline and after exposure to noise.

genetics↗