Sensitivity of the Fasciae to Sex Hormone Levels: Modulation of Collagen-I, Collagen-III and Fibrillin Production (PMID: 31557257)
Research Question
Do sex hormones influence the structure and extracellular matrix production of human fascia, and can hormonal changes alter the production of key connective tissue components such as collagen and fibrillin?
This study investigated whether fascial fibroblasts respond directly to hormonal stimulation and how this may relate to differences in connective tissue behavior.
Methods
Researchers isolated fibroblasts from human fascia lata and studied their response in vitro.
Cells were exposed to sex hormone conditions mimicking different physiological states, including:
Follicular phase
Periovulatory phase
Luteal phase
Post-menopausal phase
Pregnancy-associated hormone levels
Hormonal treatments included:
β-estradiol
Relaxin-1 (alone and in combination)
The production of extracellular matrix components was analyzed using immunocytochemical methods, focusing on:
Collagen type I
Collagen type III
Fibrillin
Key Findings
The study demonstrated that fascial cells are hormonally responsive and can modify extracellular matrix production depending on sex hormone levels.
Main findings included:
Collagen I production decreased significantly in response to β-estradiol exposure.
Reduced from ~6% in follicular-like conditions to ~1.9% in periovulatory-like conditions.
When relaxin-1 was added, extracellular matrix production decreased further and remained consistently low.
Relaxin-1 showed a strong anti-fibrotic effect, reducing overall matrix synthesis.
Changes were also observed in collagen III and fibrillin regulation, indicating broader ECM modulation.
These results suggest that fascial fibroblasts actively respond to hormonal environments and adjust their structural output accordingly.
Why It Matters for Fascia
This study supports the concept that fascia is not a static connective tissue, but a hormonally sensitive and dynamically remodeling system.
It helps explain:
Sex-related differences in fascial pain conditions (e.g., myofascial pain prevalence)
Variations in tissue stiffness across hormonal cycles
Potential links between hormonal disorders and connective tissue dysfunction
The role of hormones in regulating fibrosis and tissue remodeling
The findings also highlight relaxin-1 as a potential anti-fibrotic regulator of fascial tissue behavior.
5 Takeaways
Fascial fibroblasts respond directly to sex hormones.
β-estradiol reduces collagen I production in fascia cells.
Relaxin-1 has a strong anti-fibrotic effect on fascial ECM.
Hormonal state influences extracellular matrix composition.
Hormonal dysregulation may contribute to fascial dysfunction and pain.