HIF1A and pulmonary arterial hypertension: Studies have shown that in PAH, hypoxia upregulates CD36 expression via activation of the HIF-1α/PI3K p85α axis, promoting PASMC uptake of free FAs, thereby driving abnormal PASMC proliferation and pulmonary vascular remodeling; inhibition of CD36 in animal models significantly alleviates the pathological features of pulmonary hypertension [27].