Mexican researchers have discovered that allicin could potentially offer therapeutic benefits to patients with pulmonary arterial hypertension (PAH), according to a study published in the International Journal of Molecular Sciences. The main therapeutic actions of allicin involve slowing down 2 key features of PAH, pulmonary function decline and right ventricular hypertrophy (RVH), thus offering patients better clinical outcomes.
PAH eventually leads to the progressive destruction and remodeling of the pulmonary vascular bed, which causes a pathological increase in both pulmonary arterial pressure and pulmonary vascular resistance, eventually leading to right-sided heart failure and pulmonary decline. Allicin is a compound found naturally in garlic that is known to have anti-inflammatory and antioxidant benefits in cardiovascular disease. In addition, studies have shown that allicin treatment can be used to prevent inflammation and fibrosis in lung tissue. However, its exact mechanisms are still poorly understood.
Read more about PAH etiology
Researchers thus wanted to investigate the usefulness of allicin as a therapeutic agent in PAH. Experimental rats were used for this study. To induce PAH in the test subjects, monocrotaline (MCT) was used. The experimental subjects were divided into 3 groups:
- MCT (60 mg/kg) only
- MCT (60 mg/kg) and allicin (16 mg/kg/oral gavage)
First, to assess whether MCT-induced PAH in rats was successful, researchers assessed RVH in rats in the MCT-only group using the Fulton index and found that MCT-induced hypertrophy was significantly higher in the MCT-only group than in the control group. In addition, the MCT-only group had significantly thickened pulmonary vessel walls and narrower lumens than controls — characteristics that are commonly observed in PAH. This indicated that MCT successfully induced characteristics of PAH in experimental rats.
The most significant finding of this study is in the third group: MCT-induced PAH subjects receiving allicin treatment. Although RVH in the MCT-only group was significantly higher than in the control group, RVH in the allicin-treated group was lower than in the MCT-only group. This suggests that allicin is protective against the development of RVH.
Furthermore, less thickening of pulmonary vessel walls was seen in the MCT-allicin group compared to the MCT-only group, thus demonstrating its protective effects in maintaining the integrity of the pulmonary vasculature. The study suggests allicin is able to achieve these therapeutic effects through the modulation of profibrotic and proinflammatory biomarkers in both the heart and lungs.
The authors of the study concluded, “In brief, this study showed evidence that allicin has a protective effect on pulmonary arterial medial wall thickness and [RVH] in MCT-induced PAH.” Therefore, allicin should be considered a therapeutic option in slowing the disease progression in patients with PAH, they wrote.
Sánchez-Gloria JL, Martínez-Olivares CE, Rojas-Morales P, et al. Anti-inflammatory effect of allicin associated with fibrosis in pulmonary arterial hypertension. Int J Mol Sci. 2021;22(16):8600. doi:10.3390/ijms22168600