This discovery, published in the journal Biomedicine & Pharmocotherapy, suggests that rosavin may be a promising candidate to treat PF in humans.
To date, the only effective treatment for PF is a lung transplant. However, this treatment strategy can be expensive, is not available to all patients, and is associated with a high risk of organ rejection.
Patients have only two approved therapies at their disposal: Esbriet (pirfenidone, sold by Genentech) and Ofev (nintedanib, by Boehringer Ingelheim). Although these have been linked to significant symptom improvement and reduced disease progression rate, they fail to effectively improve PF patient’s survival.
“Therefore, it is urgent to develop new anti-pulmonary fibrosis drugs with high efficiency,” the researchers wrote.
Rhodiola rosea has been used in Chinese traditional medicine for more than 2,000 years due to the anti-inflammatory and immunity-boosting properties of rosavin, its main active compound. Despite the evidence of its potential, scientific studies on Rhodiola and the actual benefits of rosavin are still lacking.
Given the inflammatory nature of PF, Chinese researchers decided to investigate whether rosavin could play a protective role in this disease.
They treated mice with induced PF with three different doses of rosin — 50, 100, and 200 milligrams per kilogram of body weight — or with 5 mg/kg of prednisone, a steroid compound commonly used as an anti-inflammatory agent.
After assessing lung index, a tool used to determine tissue damage by changes in the size of the lungs, the team confirmed that mice with induced PF had higher scores than healthy mice (control group).
Treatment with rosavin was found to significantly decrease lung index in PF mice, with the highest dose tested showing the most reduction. In addition, the beneficial effect of rosavin was similar to that achieved with prednisone treatment.
Additional evaluations revealed that treatment with rosavin also reduced the number of inflammatory cells, namely monocytes and lymphocytes, which had infiltrated in the lungs and could be detected in bronchoalveolar lavage fluid (a technique to collect cells and fluid from the airways). This suggests that this herbal active compound could prevent the infiltration of inflammatory cells and their underlying inflammatory mechanisms in the lungs.
Rosavin was also able to reduce the load of extracellular components that often accumulate in the lungs due to PF.
Researchers found that the beneficial effects of rosavin were likely mediated by the compound’s ability to modulate the activity of genes involved in the fibrotic (scarring) and oxidative stress processes, namely the TGF-β1, α-SMA, and NF-κB p65 genes.
These results “revealed the protective effects and the primary mechanism of rosavin on … pulmonary fibrosis,” they wrote.
The team also believes that findings provide “a scientific foundation for rosavin as a promising candidate for pulmonary fibrosis treatment.”