Research Projects

Scientific projects to understand the Post-Finasteride Syndrome - funded by the PFS Research Association e. V.

How does the PFS Research Association select its research projects?

Researchers send us their PFS study proposals. The proposals are discussed with other researchers who already have been working on PFS. These study designs are eventually refined. The PFS Research Association is meeting a decision based on the scientific advice, the cost vs benefit ratio, the meaningfulness of the study, and the potential for future research projects. 

The PFS Research Association is currently working on the establishment of a scientific PFS Research Council consisting of researchers who already have published on PFS and Finasteride or researchers who might be of help to estimate the value of a certain research project. 

PROJECTS

Our Researchers

Dr George Barreto, University of Limerick, Ireland

George Barreto is a neuroscientist at the University of Limerick, Ireland. His research focus is the investigation of how sexual hormone deprivation affects the brain – especially the mitochondria.  
After completing his Ph.D. in neuroscience George Barreto spent his post-doc training at the  Stanford University School of Medicine. He is a lecturer in Cell Biology/Immunology and serves as editor of several impactful scientific journals. 
George Barreto is involved in computational and experimental drug development and has co-authored publications together with the PFS lead researchers Roberto Melcangi. 
George Barreto believes in the involvement of the mitochondria in the development of PFS. As the androgen receptor is found within the mitochondria a first study will look at how finasteride affects the androgen receptor in the mitochondria of brain cells. A second part of the study tries to figure out whether Tibolone could be a potential therapeutic target to repair possible adverse effects of finasteride on mitochondria. 

Why did we choose George Barreto's research project as our first research project?

  • First of all, George Barreto is a researcher with an excellent track record. He completed his post-doc training at the Stanford University. 
  • George Barreto’s expertise in neuroscience, molecular neurobiology, investigation of sex hormone deprivation on the brain make him a perfect candidate for a PFS researcher.
  • George Barreto is closely involved in drug development. This is the perfect opportunity to have one researcher with an overview from causation to the development of a potential cure.
  • George Barreto is editor of several well-known scientific journals and has an astonishing network of scientists. 
  • Early on George Barreto showed great interest in PFS and PSSD and already involved his students in the topic which might lead to a new generation of young driven PFS scientists.
  • The low cost-15k proposal offers a great opportunity to find out if the community and George Barreto can team up well. This is a low-risk investment with great potential upside. We hope that George Barreto might become the next generation of lead researchers for PFS research. 

1. Targeting androgen signalling for mitochondria protection in PFS

G. Barreto - University of Limerick, Ireland

The Post-Finasteride Syndrome (PFS) has not been clearly defined and there are no evidence-based effective treatments for it. First insights about its pathogenesis indicate that alterations in the SRD5A2 (one of three major isoforms of 5α-reductase) could be a possible mechanism to explain the alterations in steroid levels [1]. In fact, in the cerebrospinal fluid (CSF), levels of tetrahydroxyprogesterone, isopregnanolone and dihydroprogesterone were decreased while levels of testosterone and estradiol were increased. This pattern was mirrored in the patients’ plasma and were associated with depressive symptoms [2, 3]. Of note, mitochondria, the powerhouse of cells, are greatly regulated by androgens. The androgen receptor (AR) has a mitochondrial localization sequence that, once bound to androgen, is internalised to this organelle [4], and regulates a great variety of functions ranging from cellular metabolism to oxidative phosphorylation by promoting the transcription of mitochondrial proteins related to respiratory complexes. Any interference on the way androgens affect mitochondria may provoke devastating consequences on how this organelle processes energy substrates for ATP production. Considering these non-genomic actions of AR over mitochondria and the fact that PFS is characterized by an alteration of androgen metabolism, this likely affects mitochondria causing their dysfunction which may lead to apoptosis, dampened fatty acid metabolism and oxidative phosphorylation, augmented reactive oxidative stress (ROS), and, ultimately, promoting a pro-inflammatory environment that may endanger brain cells. Although some advances to better understand how finasteride disrupts our brain, as an attempt to seek for potential cellular targets to implement more precise therapeutic approaches, have been reported, there still exists some unsolved questions. The main aim of this project is to explore how finasteride disturbs mitochondria, causing inflammation, and repurpose an FDA-approved drug currently in use in combination with small new ligands that might be able to reduce or mitigate damage to this organelle. To tackle some of these challenges, we propose the following questions and approaches:

1. How is the androgen receptor expression at mRNA and protein levels during treatment with finasteride in brain cells (namely astrocytes and microglia)? Whether there is an overactivation or downregulation of AR, this is key to understand the participation of this receptor in PFD pathogenesis affecting the brain.

2. Is tibolone effective against mitochondrial dysfunction caused by finasteride? Tibolone is a pro-drug used by postmenopausal women to mitigate some menopause symptoms. One of its metabolites, Δ4-tibolone, binds the androgen receptor and may activate androgen signaling within mitochondria. Our lab has extensively reported the mitochondrion protective effects of tibolone in astrocytes and microglia against oxidative stress and metabolic inflammation [5-11], demonstrating this compound can be useful as drug repurposing in PFS. We will test this hypothesis in cultures of astrocytes and microglia subject to finasteride and/or tibolone (or its androgenic metabolite) and assess oxidative phosphorylation, metabolism, inflammation, mitophagy, and fusion/fission processes.

3. Is neuroglobin a druggable approach in PFS? Neuroglobin, from the globin family, is a cytosolic resident protein that, upon any cellular insult, is transported to mitochondria, interacts with respiratory complexes I and III, among other proteins, and is crucial for mitochondria wellbeing, as shown by our lab [12, 13].
Interestingly, both tibolone and testosterone boost its expression [14-16], and most of their actions over mitochondria is dependent on this protein [17, 18]. Given the fact that recombinant therapy with neuroglobin is not feasible because of its inability to cross plasma membranes, we designed a series of small ligands/drugs that could be able to induce its expression, and our aim is to test these new compounds, in combination with tibolone, as a new pharmacological scheme to mitigate mitochondria-dependent inflammation and oxidative stress when brain cells are exposed to finasteride.

The results of this pilot project will allow us to better understand how androgen signaling (e.g., AR) is affected during finasteride treatment, what implications this would have on mitochondria, and how this organelle can be protected using tibolone as a repurposing drug, and as an adjunct scheme with small drugs capable of activating neuroglobin as an experimental treatment that can be scaled to an in vivo model.

References
1. Melcangi, R.C., et al., Altered methylation pattern of the SRD5A2 gene in the cerebrospinal fluid of post-finasteride
patients: a pilot study. Endocr Connect, 2019. 8(8): p. 1118-1125.
2. Melcangi, R.C., et al., Neuroactive steroid levels are modified in cerebrospinal fluid and plasma of post-finasteride patients
showing persistent sexual side effects and anxious/depressive symptomatology. J Sex Med, 2013. 10(10): p. 2598-603.
3. Caruso, D., et al., Patients treated for male pattern hair with finasteride show, after discontinuation of the drug, altered
levels of neuroactive steroids in cerebrospinal fluid and plasma. J Steroid Biochem Mol Biol, 2015. 146: p. 74-9.
4. Bajpai, P., et al., Mitochondrial localization, import, and mitochondrial function of the androgen receptor. J Biol Chem,
2019. 294(16): p. 6621-6634.
5. Avila Rodriguez, M., et al., Tibolone protects T98G cells from glucose deprivation. J Steroid Biochem Mol Biol, 2014.
144 Pt B: p. 294-303.
6. Crespo-Castrillo, A., et al., The Synthetic Steroid Tibolone Decreases Reactive Gliosis and Neuronal Death in the Cerebral
Cortex of Female Mice After a Stab Wound Injury. Mol Neurobiol, 2018. 55(11): p. 8651-8667.
7. Del Rio, J.P., et al., Tibolone as Hormonal Therapy and Neuroprotective Agent. Trends Endocrinol Metab, 2020. 31(10):
p. 742-759.
8. Gonzalez-Giraldo, Y., et al., Tibolone attenuates inflammatory response by palmitic acid and preserves mitochondrial
membrane potential in astrocytic cells through estrogen receptor beta. Mol Cell Endocrinol, 2019. 486: p. 65-78.
9. Gonzalez-Giraldo, Y., et al., Tibolone Preserves Mitochondrial Functionality and Cell Morphology in Astrocytic Cells
Treated with Palmitic Acid. Mol Neurobiol, 2018. 55(5): p. 4453-4462.
10. Gonzalez-Giraldo, Y., et al., TERT inhibition leads to reduction of IL-6 expression induced by palmitic acid and interferes
with the protective effects of tibolone in an astrocytic cell model. J Neuroendocrinol, 2019. 31(8): p. e12768.
11. Martin-Jimenez, C., et al., Tibolone Ameliorates the Lipotoxic Effect of Palmitic Acid in Normal Human Astrocytes.
Neurotox Res, 2020. 38(3): p. 585-595.
12. Baez, E., et al., Protection by Neuroglobin Expression in Brain Pathologies. Front Neurol, 2016. 7: p. 146.
13. Gorabi, A.M., et al., The potential of mitochondrial modulation by neuroglobin in treatment of neurological disorders.
Free Radic Biol Med, 2020.
14. Avila-Rodriguez, M., et al., Tibolone protects astrocytic cells from glucose deprivation through a mechanism involving
estrogen receptor beta and the upregulation of neuroglobin expression. Mol Cell Endocrinol, 2016. 433: p. 35-46.
15. Hidalgo-Lanussa, O., et al., Tibolone Reduces Oxidative Damage and Inflammation in Microglia Stimulated with Palmitic
Acid through Mechanisms Involving Estrogen Receptor Beta. Mol Neurobiol, 2018. 55(7): p. 5462-5477.
16. Toro-Urrego, N., et al., Testosterone Protects Mitochondrial Function and Regulates Neuroglobin Expression in Astrocytic
Cells Exposed to Glucose Deprivation. Front Aging Neurosci, 2016. 8: p. 152.
17. Baez-Jurado, E., et al., Mitochondrial Neuroglobin Is Necessary for Protection Induced by Conditioned Medium from
Human Adipose-Derived Mesenchymal Stem Cells in Astrocytic Cells Subjected to Scratch and Metabolic Injury. Mol
Neurobiol, 2019. 56(7): p. 5167-5187.
18. Baez-Jurado, E., et al., Blockade of Neuroglobin Reduces Protection of Conditioned Medium from Human Mesenchymal
Stem Cells in Human Astrocyte Model (T98G) Under a Scratch Assay. Mol Neurobiol, 2018. 55(3): p. 2285-2300.

The Post-Finasteride Syndrome (PFS) has not been clearly defined and there is no evidence based effective
treatments for it. First insights about its pathogenesis indicate that alterations in the SRD5A2 (one of three
major isoforms of 5α-reductase) could be a possible mechanism to explain the alterations in steroid levels [1].
In fact, in the cerebrospinal fluid (CSF), levels of tetrahydroxyprogesterone, isopregnanolone and
dihydroprogesterone were decreased while levels of testosterone and estradiol were increased. This pattern
was mirrored in the patients’ plasma and were associated with depressive symptoms [2, 3]. Of note,
mitochondria, the powerhouse of cells, are greatly regulated by androgens. The androgen receptor (AR) has a
mitochondrial localization sequence that, once bound to androgen, is internalised to this organelle [4], and
regulates a great variety of functions ranging from cellular metabolism to oxidative phosphorylation by
promoting the transcription of mitochondrial proteins related to respiratory complexes. Any interference on
the way androgens effect mitochondria may provoke devastating consequences on how this organelle
processes energy substrates for ATP production. Considering these non-genomic actions of AR over
mitochondria and the fact that PFS is characterized by an alteration of androgen metabolism, this likely affects
mitochondria causing their dysfunction which may lead to apoptosis, dampened fatty acid metabolism and

oxidative phosphorylation, augmented reactive oxidative stress (ROS), and, ultimately, promoting a pro-
inflammatory environment that may endanger brain cells. Although some advances to better understand how

finasteride disrupts our brain, as an attempt to seek for potential cellular targets to implement more precise
therapeutic approaches, have been reported, there still exists some unsolved questions. The main aim of this

project is to explore how finasteride disturbs mitochondria, causing inflammation, and repurpose an FDA-
approved drug currently in use in combination with small new ligands that might be able to reduce or mitigate

damage to this organelle. To tackle some of these challenges, we propose the following questions and
approaches:
1- How is the androgen receptor expression at mRNA and protein levels during treatment with finasteride in
brain cells (namely astrocytes and microglia)? Whether there is an overactivation or downregulation of AR,
this is key as to understand the participation of this receptor in PFD pathogenesis affecting the brain.
2- Is tibolone effective against mitochondrial dysfunction caused by finasteride? Tibolone is a pro-drug used
by postmenopausal women to mitigate some of the menopause’s symptoms. One of its metabolites, Δ4-
tibolone, binds the androgen receptor and may activate androgen signalling within mitochondria. Our lab has
extensively reported the mitochondrion protective effects of tibolone in astrocytes and microglia against
oxidative stress and metabolic inflammation [5-11], demonstrating this compound can be useful as drug
repurposing in PFS. We will test this hypothesis in cultures of astrocytes and microglia subject to finasteride
and/or tibolone (or its androgenic metabolite) and assess oxidative phosphorylation, metabolism,
inflammation, mitophagy and fusion/fission processes.
3- Is neuroglobin a druggable approach in PFS? Neuroglobin, from the globin family, is a cytosolic resident
protein that, upon any cellular insult, is transported to mitochondria, interacts with respiratory complexes I
and III, among other proteins, and is crucial for mitochondria wellbeing, as shown by our lab [12, 13].
Interestingly, both tibolone and testosterone boost its expression [14-16], and most of their actions over
mitochondria is dependent on this protein [17, 18]. Given the fact that recombinant therapy with neuroglobin
is not feasible because of its inability to cross plasma membranes, we designed a series of small ligands/drugs
that could be able to induce its expression, and our aim is to test these new compounds, in combination with
tibolone, as a new pharmacological scheme to mitigate mitochondria-dependent inflammation and oxidative
stress when brain cells are exposed to finasteride.
The results of this pilot project will allow us to better understand how androgen signalling (e.g., AR) is affected
during finasteride treatment, what implications this would have on mitochondria, and how this organelle can

be protected using tibolone as a repurposing drug, and as adjunct scheme with small drugs capable of
activating neuroglobin as an experimental treatment that can be scaled to an in vivo model.

References
1. Melcangi, R.C., et al., Altered methylation pattern of the SRD5A2 gene in the cerebrospinal fluid of post-finasteride
patients: a pilot study. Endocr Connect, 2019. 8(8): p. 1118-1125.
2. Melcangi, R.C., et al., Neuroactive steroid levels are modified in cerebrospinal fluid and plasma of post-finasteride patients
showing persistent sexual side effects and anxious/depressive symptomatology. J Sex Med, 2013. 10(10): p. 2598-603.
3. Caruso, D., et al., Patients treated for male pattern hair with finasteride show, after discontinuation of the drug, altered
levels of neuroactive steroids in cerebrospinal fluid and plasma. J Steroid Biochem Mol Biol, 2015. 146: p. 74-9.
4. Bajpai, P., et al., Mitochondrial localization, import, and mitochondrial function of the androgen receptor. J Biol Chem,
2019. 294(16): p. 6621-6634.
5. Avila Rodriguez, M., et al., Tibolone protects T98G cells from glucose deprivation. J Steroid Biochem Mol Biol, 2014.
144 Pt B: p. 294-303.
6. Crespo-Castrillo, A., et al., The Synthetic Steroid Tibolone Decreases Reactive Gliosis and Neuronal Death in the Cerebral
Cortex of Female Mice After a Stab Wound Injury. Mol Neurobiol, 2018. 55(11): p. 8651-8667.
7. Del Rio, J.P., et al., Tibolone as Hormonal Therapy and Neuroprotective Agent. Trends Endocrinol Metab, 2020. 31(10):
p. 742-759.
8. Gonzalez-Giraldo, Y., et al., Tibolone attenuates inflammatory response by palmitic acid and preserves mitochondrial
membrane potential in astrocytic cells through estrogen receptor beta. Mol Cell Endocrinol, 2019. 486: p. 65-78.
9. Gonzalez-Giraldo, Y., et al., Tibolone Preserves Mitochondrial Functionality and Cell Morphology in Astrocytic Cells
Treated with Palmitic Acid. Mol Neurobiol, 2018. 55(5): p. 4453-4462.
10. Gonzalez-Giraldo, Y., et al., TERT inhibition leads to reduction of IL-6 expression induced by palmitic acid and interferes
with the protective effects of tibolone in an astrocytic cell model. J Neuroendocrinol, 2019. 31(8): p. e12768.
11. Martin-Jimenez, C., et al., Tibolone Ameliorates the Lipotoxic Effect of Palmitic Acid in Normal Human Astrocytes.
Neurotox Res, 2020. 38(3): p. 585-595.
12. Baez, E., et al., Protection by Neuroglobin Expression in Brain Pathologies. Front Neurol, 2016. 7: p. 146.
13. Gorabi, A.M., et al., The potential of mitochondrial modulation by neuroglobin in treatment of neurological disorders.
Free Radic Biol Med, 2020.
14. Avila-Rodriguez, M., et al., Tibolone protects astrocytic cells from glucose deprivation through a mechanism involving
estrogen receptor beta and the upregulation of neuroglobin expression. Mol Cell Endocrinol, 2016. 433: p. 35-46.
15. Hidalgo-Lanussa, O., et al., Tibolone Reduces Oxidative Damage and Inflammation in Microglia Stimulated with Palmitic
Acid through Mechanisms Involving Estrogen Receptor Beta. Mol Neurobiol, 2018. 55(7): p. 5462-5477.
16. Toro-Urrego, N., et al., Testosterone Protects Mitochondrial Function and Regulates Neuroglobin Expression in Astrocytic
Cells Exposed to Glucose Deprivation. Front Aging Neurosci, 2016. 8: p. 152.
17. Baez-Jurado, E., et al., Mitochondrial Neuroglobin Is Necessary for Protection Induced by Conditioned Medium from
Human Adipose-Derived Mesenchymal Stem Cells in Astrocytic Cells Subjected to Scratch and Metabolic Injury. Mol
Neurobiol, 2019. 56(7): p. 5167-5187.
18. Baez-Jurado, E., et al., Blockade of Neuroglobin Reduces Protection of Conditioned Medium from Human Mesenchymal
Stem Cells in Human Astrocyte Model (T98G) Under a Scratch Assay. Mol Neurobiol, 2018. 55(3): p. 2285-2300.