Plasma-Free Amino Acid Profiling of Nasal Polyposis Patients

Aim and Objective: To determine the mechanisms present in the etiopathogenesis of nasal polyposis. It is not clear whether amino acids contribute in a causal way to the development of the disease. Therefore, the aim of this study was to determine the plasma-free amino acid profile in patients with nasal polyposis and to compare the results with a healthy control group. Materials and Methods: This was a prospective controlled study that took place in the Otolaryngology Department at the Harran University Faculty of Medicine between April 2017 and April 2018. Plasmafree amino acid profile levels were studied in serum samples taken from a patient group and a healthy control group. Patients who were diagnosed with bilateral diffuse nasal polyposis and were scheduled for surgical interventions were included in this study. Individuals whose age, gender, and body mass index values were compatible with that of the patient group and who did not have any health problems were included in the control group. All the participants whose levels of plasma-free amino acid were thought to be affected by one or more of the following factors were excluded from the study: smoking and alcohol use, allergic rhinitis presence, the presence of acute or chronic sinusitis, a history of endoscopic sinus surgery, unilateral nasal masses, a history of chronic drug use, systemic or topical steroid use in the last three months for any reason, and liver, kidney, hematological, cardiovascular, metabolic, neurological, or psychiatric disorders or malignancies. Results: In patients with nasal polyposis, 3-methyl histidine (3-MHIS: nasal polyposis group (ng) = 3.22 (1.92 – 6.07); control group (cg) = 1.21 (0.77 – 1.68); p = 0.001); arginine (arg: ng = 98.95 (70.81 – 117.75); cg = 75.10 (54.49 – 79.88); p = 0.005); asparagine (asn: ng = 79.84 (57.50 – 101.44); cg = 60.66 (46.39 – 74.62); p = 0.021); citrulline (cit: ng = 51.83 (43.81 – 59.78); cg = 38.33 (27.81 – 53.73); p = 0.038); cystine (cys: ng = 4.29 (2.43 – 6.66); cg = 2.41 (1.51 – 4.16); p = 0.019); glutamic acid (glu: ng = 234.86 (128.75 – 286.66); cg = 152.37 (122.51 – 188.34); p = 0.045); histidine (his: ng = 94.19 (79.34 – 113.99); cg = 74.80 (62.76 – 98.91); p = 0.018); lysine (lys: ng = 297.22 (206.55 – 371.25); cg = 179.50 (151.58 – 238.02); p = 0.001); ornithine (ng = 160.62 (128.36 – 189.32); cg = 115.91 (97.03 – 159.91); p = 0.019); serine (ser: ng = 195.15 (151.58 – 253.07); cg = 83.07 (67.44 – 92.44); p = 0.001); taurine (tau: ng = 74.69 (47.00 – 112.13); cg = 53.14 (33.57 – 67.31); p = 0.006); tryptophan (trp: ng = 52.31 (33.81 – 80.11); cg = 34.44 (25.94 – 43.07); p = 0.005), homocitrulline (ng = 1.75 (1.27 – 2.59); cg = 0.00 (0.00 – 0.53); p = 0.001); norvaline (ng = 6.90 (5.61 – 9.18); cg = 4.93 (3.74 – 7.13); p = 0.021); argininosuccinic acid (ng = 14.33 (10.06 – 25.65); cg = 12.22 (5.77 – 16.87) p = 0.046); and plasma concentrations were significantly higher than in the healthy control group (p <0.05). However, the gamma-aminobutyric acid (gaba: ng = 0.16 (0.10 – 0.24); cg = 0.21 (0.19 – 0.29); p = 0.010) plasma concentration was significantly lower in the nasal polyposis group than in the healthy control group. Conclusion: In this study, plasma levels of 15 free amino acids were significantly higher in the nasal polyposis group than in the healthy control group. A plasma level of 1 free amino acid was found to be significantly lower in the nasal polyposis group compared to the healthy control group. Therefore, it is important to determine the possibility of using the information obtained to prevent the recurrence of the condition and to develop effective treatment strategies. This study may be a milestone for studies of this subject. However, this study needs to be confirmed by further studies conducted in a larger series.