Sasha (Alexandra) Maximova

Sasha majored in Pharmacology while completing her Bachelor of Medical Science at USYD. This exposure made her realise her passion for Pharmacology – specifically the drug design aspect – and led her to approach Prof Michael Kassiou with interest in an Honours project under his supervision. Her Honours project focused on drug design for targeting the oxytocin signalling pathway as an avenue for therapeutics to treat social disorders. This opportunity allowed her to experience working in a lab-based research environment with some of the most gifted people she knows. Sasha enjoyed this process immensely, thus deciding to further pursue this career path by beginning her PhD under the supervision of Dr Eryn Werry and Prof Michael Kassiou, with a focus on drug design in neurodegeneration.

Forefront Group: Medicinal Chemistry & Drug Discovery

Supervisors:

Dr Eryn Werry and Professor Michael Kassiou

Expertise:

  • Neuropathology
  • Biomarkers
  • GPCR signalling

Affiliate Organisations:

The University of Sydney

Neurodegeneration of interest:

Amyotrophic Lateral Sclerosis (ALS) and Alzheimer’s Disease (AD)

Specific Skills:

  • Cell culture work
  • Radioligand binding
  • Fluorescence-based assays
  • High-throughput screening assays

Project - Exploring cell senescence in neurodegeneration (2020-2024)

Disease area:

ALS, AD

Research Project Description

Exploring the extent of and the mechanisms involved in senescence in AD and ALS in post-mortem human tissue

This project will involve deriving control and disease iPSCs intro astrocytes and microglia and using immunohistochemistry to confirm cell identity with β-galactosidase staining and bromodeoxyuridine, which identifies proliferating, non-senescent cells. Once identity is confirmed, these cells will be used to explore the mechanisms of senescence in AD by utilising qRT-PCR to identify known genetic markers of senescence in cells, including p16INK4a, Il6, and Il1b. Furthermore, ELISA will be used to identify and quantify cytokine secretions, followed by protein extraction and western blot analysis to observe any protein aggregation. I may further confirm this using the thioflavin assay to identify phosphorylated tau protein aggregates.

Developing a pre-clinical senolytic lead through screening on iPSC-derived microglia and astrocytes and studying its structure-activity relationship

iPSC derivation into astrocytes and microglia will be performed in conjunction with a drug screening process using ligands designed and synthesised by the Kassiou Drug Discovery Lab, combined with a western blot analysis for proteins involved in senescence regulation. Further probing of the senolytic mechanism of action through mechanistic studies involving proteomics using mass spectrometry, and genomic analysis using fluorometric arrays, will be performed by introducing antagonists to vehicle- and drug-treated cells and observing the effect the response has on the p53 pathway, which is known to be involved in senescence, to determine whether it is acting directly or indirectly. Based on the results, further drug iterations will be suggested.

Disease tissue imaging

Brain slice imaging of disease-relevant areas – including the spinal cord and the motor cortex for ALS, and cortex and hippocampus for AD – will be performed using immunofluorescence and two-photon excitation microscopy. Image analysis will be performed via co-staining for senescence and glial markers and quantitating the percentage of senescent glial cells in diseased tissue compared to controls.