Luffa operculata affects mucociliary function of the isolated frog palate

Luffa operculata is a medicinal plant used in homeopathic and alternative medicine. In the United States, it is sold in a purified spray form, whereas a homemade L. operculata dry fruit infusion (DFI) is commonly used in Latin America. The L. operculata DFI is applied intranasally, inducing profuse mucous secretion and relieving nasal symptoms. Nevertheless, this medication may cause irritation of the nasal mucosa, as well as epistaxis or anosmia. Given the growing popularity of alternative medicine, a decision was made to evaluate the effects of this substance on mucous membranes.

The effects of L. operculata DFI on mucociliary transport velocity, ciliary beat frequency, and transepithelial potential difference (PD) were evaluated in an isolated frog palate preparation. We tested 46 palates immediately before immersion and again at 5 and 20 minutes after immersion. Four groups (n = 10) were tested in frog Ringer: control; L. operculata DFI, 60 mg/L; 600 mg/L; and 1200 mg/L. An additional group was tested using L. operculata DFI prepared with water (600 mg/L of H2O, n = 6). Epithelial samples were harvested for ultrastructural study.

In treated palates, mucociliary transport velocity and ciliary beat frequency decreased significantly (p < 0.001 and p < 0.008, respectively). There was a dose-dependent decrease in PD modulus (p < .007). Our PD findings indicated ion-fluid transport abnormalities, which were confirmed by transmission electron microscopy that showed enlargement of interepithelial spaces.

In this ex vivo model, the L. operculata DFI infusion promoted significant changes in the mucociliary function of the epithelium, suggesting that it is potentially noxious to human nasal mucosa.