Theophylline increases saliva sonic hedgehog and improves taste dysfunction.

OBJECTIVE: To determine changes in saliva sonic hedgehog (Shh) and in taste dysfunction before and after oral theophylline treatment. DESIGN: Shh was measured in parotid saliva of both normal subjects and patients with taste dysfunction of multiple etiologies by use of a sensitive spectrophotometric ELISA assay. Taste dysfunction was defined clinically by both subjective inhibition of taste function (including acuity loss) and impaired gustometry. RESULTS: Theophylline treatment increased patient saliva Shh and improved taste dysfunction both subjectively and by gustometry. CONCLUSIONS: By use of these systematic clinical measurements theophylline can be demonstrated to increase saliva Shh and improve taste dysfunction. These results are consistent with saliva Shh acting as a taste bud growth factor which stimulates stem cells of taste buds to initiate development and perpetuation of taste bud receptors. Measurements of saliva Shh provide an important marker for the presence of taste dysfunction and in the improvement by theophylline treatment.

Sonic hedgehog is present in parotid saliva and is decreased in patients with taste dysfunction.

PURPOSE: To demonstrate that sonic hedgehog (Shh) is present in human parotid saliva and is decreased in human taste dysfunction. METHODS: Shh was measured in parotid saliva of 27 normal subjects and 81 patients with taste dysfunction of multiple etiologies using a sensitive spectrophotometric ELISA assay. Taste dysfunction was defined clinically both by subjective decreases of taste acuity and flavor perception and by impaired gustometry. RESULTS: Shh was found in parotid saliva of both normal subjects and patients with taste dysfunction. Levels were significantly lower in patients than in normal subjects. Both subjective loss of taste acuity and flavor perception and impaired gustometry was measured in untreated patients. CONCLUSIONS: This is the first demonstration of Shh in human saliva. As Shh has been related to taste bud growth and development, its presence in saliva is consistent with its role as a cell signaling moiety involved with stimulation of taste bud stem cells to generate taste receptors. Decreased saliva Shh secretion can be considered a marker of taste dysfunction in patients with multiple pathologies for their dysfunction.

Improved smell function with increased nasal mucus sonic hedgehog in hyposmic patients after treatment with oral theophylline.

PURPOSE: We previously demonstrated the presence of sonic hedgehog (Shh) in nasal mucus in normal subjects and in patients with smell loss (hyposmia). Nasal mucus Shh levels were found significantly diminished in untreated hyposmic patients of multiple etiologies. Since treatment with oral theophylline has been previously associated with improvement in smell function we wished to study if such treatment increased nasal mucus Shh as well as improved smell function in patients with hyposmia. METHODS: Forty-four patients with hyposmia of several etiologies were evaluated for changes in hyposmia by subjective measurements of smell, taste and flavor perception and by olfactometry. Measurements of nasal mucus Shh were made in relationship to each set of sensory measurements. Patients were treated with oral theophylline at doses of 200-800mg for periods of 2-10months with sensory function, nasal mucus Shh and serum theophylline levels evaluated at these time intervals. Nasal mucus Shh measurements were made with a sensitive spectrophotometric ELISA assay and theophylline with a fluorometric assay. RESULTS: There was consistent, significant improvement in subjective responses in smell, taste and flavor perception and in olfactometry associated with increased nasal mucus Shh and serum theophylline after theophylline treatment. CONCLUSIONS: Improvement in smell function and in nasal mucus Shh was positively correlated in a dose-response relationship after treatment with oral theophylline. Results are consistent with a successful role for theophylline in improvement of smell function in hyposmic patients of multiple etiologies associated with increased nasal mucus Shh which can act as a biochemical marker for smell function.

A genetic marker of the ACKR1 gene is present in patients with Type II congenital smell loss who have type I hyposmia and hypogeusia.

PURPOSE: Our previous study of Type II congenital smell loss patients revealed a statistically significant lower prevalence of an FY (ACKR1, formerly DARC) haplotype compared to controls. The present study correlates this genetic feature with subgroups of patients defined by specific smell and taste functions. METHODS: Smell and taste function measurements were performed by use of olfactometry and gustometry to define degree of abnormality of smell and taste function. Smell loss was classified as anosmia or hyposmia (types I, II or III). Taste loss was similarly classified as ageusia or hypogeusia (types I, II or III). Based upon these results patient erythrocyte antigen expression frequencies were categorized by smell and taste loss with results compared between patients within the Type II group and published controls. RESULTS: Comparison of antigen expression frequencies revealed a statistically significant decrease in incidence of an Fyb haplotype only among patients with type I hyposmia and any form of taste loss (hypogeusia). In all other patient groups erythrocyte antigens were expressed at normal frequencies. CONCLUSIONS: Data suggest that Type II congenital smell loss patients who exhibit both type I hyposmia and hypogeusia are genetically distinct from all other patients with Type II congenital smell loss. This distinction is based on decreased Fyb expression which correlated with abnormalities in two sensory modalities (hyposmia type I and hypogeusia). Only patients with these two specific sensory abnormalities expressed the Fyb antigen (encoded by the ACKR1 gene on the long arm of chromosome 1) at frequencies different from controls.

Erythrocyte membrane antigen frequencies in patients with Type II congenital smell loss.

OBJECTIVE: The objective of this study was to determine whether there are genetic factors associated with Type II congenital smell loss. STUDY DESIGN: The expression frequencies of 16 erythrocyte antigens among patients with Type II congenital smell loss were determined and compared to those of a large control group. METHODS: Blood samples were obtained from 99 patients with Type II congenital smell loss. Presence of the erythrocyte surface antigens A, B, M, N, S, s, Fy(a), Fy(b), D, C, c, E, e, K, Jk(a), and Jk(b) was analyzed by blood group serology. Comparisons of expression frequencies of these antigens were made between the patients and a large control group. RESULTS: Patients tested for the Duffy b antigen (Fy(b) haplotype) exhibited a statistically significant 11% decrease in expression frequency compared to the controls. There were no significant differences between patients and controls in the expression frequencies for all other erythrocyte antigens (A, B, M, N, S, s, Fy(a), D, C, c, E, e, K, Jk(a), or Jk(b)). CONCLUSIONS: These findings describe the presence of a previously unrevealed genetic tendency among patients with Type II congenital smell loss related to erythrocyte surface antigen expression. The deviation in expression rate of Duffy b suggests a target gene and chromosome region in which future research into this form of congenital smell loss may reveal a more specific genetic basis for Type II congenital smell loss.