Cynomorium Songaricum polysaccharides ameliorate erectile dysfunction through potent inhibition of...

Cynomorium Songaricum (CS), known in Traditional Chinese Medicine as "Suoyang," has a long history of use for treating male sexual dysfunction. However, the specific bioactive components responsible for this effect and their underlying molecular mechanisms have not been fully elucidated.

The present study aimed to isolate and structurally characterize the bioactive polysaccharides from CS and to investigate their therapeutic mechanism for treating erectile dysfunction.

CS polysaccharides (CSP) were extracted from CS, purified via ion-exchange and size-exclusion chromatography, and the active fractions were structurally characterized using HPGPC, methylation analysis, and NMR spectroscopy. The fractions' pro-erectile potential was evaluated in vitro through PDE5A inhibition and cell-based assays, and in vivo using an orchiectomized rat model to assess intracavernosal pressure, mating behavior, and acute toxicity.

CSP inhibits PDE5 enzyme activity in a dose-dependent manner with an IC₅₀ value of 37.73 μg/mL. Pharmacological studies further reveal that CSP elevates cyclic guanosine monophosphate (cGMP) levels both in vitro and in vivo, and increases intracavernosal pressure (ICP) in rats, confirming its therapeutic efficacy in a model of ED. Absorption studies using a Caco-2 cell model indicated that can be effectively absorbed, and safety assessments indicate that CSP is a non-toxic natural bioactive compound. Furthermore, two homogeneous polysaccharides, designated CSP-A-1 and CSP-A-2, were isolated from the crude CSP, both of which displayed high affinity for PDE5.

This study establishes CSP as a novel class of safe and effective natural PDE5 inhibitors, validating their traditional use for erectile dysfunction and positioning them as a promising agent for future development and optimization.