The Professional Journey from Medical Laboratory Pathologist to Astropathologist: A Q&A with Saswati Das, MD

 Saswati Das, MD, FASCP, became deeply curious about how extreme environments, like space, affect human physiology. Her extensive training—at the International Space University and specialized programs at ESA and NASA—provided a gateway into the field of astropathology.  

Here, Dr. Das discusses the intersection of pathology and space medicine, shares insights from engaging in international space health collaborations, and her vision for impacting the future of health on Earth.* 

Critical Values (CV): What led you to combine your expertise in pathology with a focus on space health? 

Saswati Das (SD): My fascination with the intersection of human biology and extreme environments led me to integrate space health into my career in pathology.  

In space medicine, stressors are even more extreme—microgravity, isolation, circadian disruption, and cosmic radiation. Pathology explains mechanisms, tracks progression, and identifies targets for intervention.  

That perspective is critical when planning long-duration space missions where Earth-based interventions are not feasible. 

CV: Can you describe your role as a pathologist within the context of space missions or astronaut health? 

SD: In the realm of space health, my role as a pathologist transcends traditional microscopy. I focus on molecular and systems biology, using omics technologies and AI analytics to examine how biological systems are perturbed in space.  

I serve as an analyst and contributor to datasets derived from rodent models aboard the International Space Station (ISS), organoid experiments, and space analog missions.  

I am also involved in collaborative work with several trans-disciplinary international projects, which investigates adaptations in space.  

CV: What are some of the most unique challenges you face when studying disease or tissue changes in microgravity? 

SD: One major challenge is the lack of real time pathology aboard spacecraft. Unlike on earth, we cannot perform biopsies, histopathology, or even basic centrifugation with ease in microgravity.  

This limits the type and volume of samples that can be collected and analyzed during a mission.  

Microgravity also alters cellular architecture. Cells exhibit changes that distort traditional pathological markers, making it harder to compare space samples to terrestrial baselines. 

CV: How does space travel affect the human body at the cellular or tissue level, and what role does pathology play in monitoring those changes? 

SD: Spaceflight induces a cascade of physiological and cellular responses.  

At the tissue level, we observe bone demineralization, muscle atrophy, and cardiovascular remodeling.  

At the cellular level, space travel triggers mitochondrial dysfunction, immune suppression, DNA damage, and oxidative stress due to radiation exposure, as well as disruption of cell polarity and cytoskeletal integrity affecting tissue repair. 

Astropathology plays a central role in monitoring these changes, contributing to the identification of thresholds for intervention and tailored countermeasures designs.  

CV: Have you been involved in analyzing biological samples from astronauts? If so, what types of changes have you observed compared to Earth-based samples? 

SD: Direct astronaut sample access is often restricted; however, I have worked extensively on multi-omics datasets from space-flown rodents and organoid models. 

I have found upregulation of oxidative stress and inflammatory pathways, dysregulation of lipid metabolism and calcium homeostasis, altered expression of DNA repair genes and tumor suppressors, reflecting genomic instability. 

CV: How does radiation exposure in space influence disease development, and what can pathology teach us about those risks? 

SD: Radiation in space, particularly Galactic Cosmic Rays, poses a unique risk. These effects can accelerate oncogenesis, impair tissue regeneration, and induce neuroinflammation. 

By studying tissue-level responses in irradiated animal models and organoids, we can better understand latency periods, dose thresholds, and individual susceptibility which is vital for formulating radiation shielding strategies.  

CV: Are there any specific diseases or conditions that are more likely to emerge or behave differently in space environments? 

SD: Several conditions demonstrate altered incidence or progression in space including, osteoporosis and renal stones, spaceflight-associated neuro-ocular syndrome (SANS), latent viral reactivations, thrombosis risk, and cancer. 

Additionally, wound healing and microbial virulence behave differently in microgravity, potentially complicating medical interventions during missions. 

CV: What technologies or innovations are being used to conduct pathology research or diagnostics in space or in analog environments like space habitats? 

SD: Innovations currently in use, or in development, in space include lab-on-a-chip systems for blood, saliva, and urine analysis; portable qPCR for nucleic acid detection; microfluidic immunoassays for monitoring cytokines and biomarkers;3D bioprinters for tissue modeling and regenerative experiments; and AI-based telepathology platforms which allow Earth-based experts to analyze scanned tissue images. Meanwhile, organ-on-chip, robotic tissue culture and space-grown organoids are used for modeling human physiology and pathology. 

In space analog missions and analog habitats — NEEMO, HI-SEAS, or Lunares — these tools are tested for ruggedness, minimal reagent usage, and ease of interpretation by non-experts. 

CV: How do your findings contribute to preparing astronauts for long-duration missions, such as to Mars or deep space? 

SD: My research contributes to risk profiling, precision health monitoring, and adaptive countermeasures.  

By identifying early molecular changes and preclinical pathology, we can predict individual vulnerabilities to radiation or immune dysfunction. We can also tailor countermeasures, design health surveillance protocols, and support the development of systems for remote diagnostics.  

These strategies are critical for deep space and Mars missions, where evacuation to Earth is not possible, and medical autonomy becomes essential. 

CV: What excites you most about the future of pathology in space health, and what questions are you hoping to answer next? 

SD: I am most excited about the potential for space health research to transform terrestrial medicine. I am currently engaged with multiple ESA and NASA biosciences teams. We are exploring how spaceflight alters gene expression, immunity, brain function, and tissue health.  

One of the most fascinating areas I work on involves cancer biology in space, women’s health in microgravity, and musculoskeletal degradation. They all have profound implications for both astronauts and patients on Earth. 

My goal is to bridge space health, AI enabled diagnostics, and global public health equity by leveraging insights from the most extreme frontier of medicine. 

*This interview has been edited for clarity and length.