Salivary proteome and glucose levels are related with sweet taste sensitivity in young adults

Figures & data

Table 1. Percentage of normal weight and overweight individuals belonging to each sweet taste sensitivity group.

		% individuals
	IMC (kg/m^2)	«25	>25
Sweet taste sensitivity group	Sensitive	49.1	51.5
	Low-sensitive	50.9	48.5

Table 2. Comparison of salivary parameters (mean ± standard error) between sweet taste sensitivity groups.

Salivary parameters (mean ± standard error)^a
	Sensitive	Low-sensitive	P
Total protein concentration (µg/mL)	446.07 ± 21.55	458.98 ± 19.95	0.662
Saliva flow rate (mL/min)	0.52 ± 0.03	0.57 ± 0.03	0.191
pH	7.60 ± 0.08	7.64 ± 0.11	0.774

^aThese values refer to the total of individuals under study.

Table 3. MS identification of the salivary proteins differentially expressed among taste sensitivity groups.

Band	Protein	Uniprot entry reference	Estimated/theoretical MW (kDa)	Id score	Sequence coverage (%)	No. peptides matched
B	Not identified	–	120.0/–	–	–	–
C	Polymeric immunoglobulin receptor	P01833	84.9/84.4	107	21	13
E	Alpha-amylase 1	P04745	66.5/57.8	135	31	15
F			57.1/57.8	100	21	9
J	Cystatin-SN	P01037	14.4/16.6	99	60	7

Figure 1. Protein bands differing between the two sweet sensitivity groups.

* Differences are statistically significant for P < 0.05.

Table 4. Details of mass spectrometry results for protein spots associated with sweet taste sensitivity. Comparisons between sweet taste sensitivity groups are presented.

Spot	Protein	Uniprot entry reference	Estimated/theoretical MW (kDa)	Estimated/theoretical pI	Mascot ID Score	Seq. C (%)	No. peptide matched	% Volume (mean ± standard error)
								Sensitive	Low-sensitive	P
Men + Women
25	Cystatin-S	P01036	13.4/16.5	4.9/4.95	127	67	8	9.05 ± 0.92	4.55 ± 0.84	0.002
63	Carbonic anhydrase 6	P23280	38.6/35.5	5.9/6.51	71	19	5	0.22 ± 0.05	0.39 ± 0.04	0.013
64			37.8/35.5	6/6.51	55	19	5	0.14 ± 0.02	0.21 ± 0.02	0.031
65			37.1/35.5	6.5/6.51	94	30	8	0.07 ± 0.007	0.09 ± 0.009	0.032
Men
7	Ig kappa chain C region	P01834	26.4/11.8	6/5.58	44	48	3	0.27 ± 0.06	0.46 ± 0.06	0.022
13	Cysteine-rich secretory protein 3	P54108	31.0/28.5	7.0/8.09	51	17	4	0.14 ± 0.02	0.24 ± 0.03	0.005
19	Serum albumin	Q86YG0	73.7/71.3	5.6/5.92	132	28	15	0.95 ± 0.16	0.49 ± 0.09	0.015
25	Cystatin-S	P01036	13.4/16.5	4.9/4.95	127	67	8	11.09 ± 1.30	5.27 ± 0.25	0.010
46	Actin cytoplasmic 1	Q96HG5	55.9/42.1	5.4/5.29	121	42	11	0.16 ± 0.03	0.29 ± 0.05	0.035
63	Carbonic anhydrase 6	P23280	38.6/35.5	5.9/6.51	71	19	5	0.22 ± 0.03	0.41 ± 0.07	0.028
64			37.8/35.5	6/6.51	55	19	5	0.15 ± 0.02	0.24 ± 0.03	0.042
66	Alpha-amylase 1	P04745	43.6/58.4	5.6/6.47	146	25	13	0.04 ± 0.01	0.08 ± 0.02	0.003
Women
27	Ig kappa chain C region	P01834	25.9/11.8	5.6/5.58	68	50	4	0.41 ± 0.05	0.27 ± 0.02	0.018
55			25.9/11.8	6.5/5.58	80	50	4	2.70 ± 0.35	1.78 ± 0.21	0.023
31	Polymeric immunoglobulin receptor	P12273	16.4/16.8	5.2/8.26	154	55	9	0.21 ± 0.06	0.39 ± 0.06	0.037
65	Carbonic anhydrase 6	P23280	37.1/35.5	6.5/6.51	94	30	8	0.07 ± 0.01	0.11 ± 0.01	0.008
77	Alpha-amylase 1	P04745	49.7/58.4	5.7/6.47	147	38	17	0.24 ± 0.03	0.36 ± 0.03	0.013
78			59.4/58.4	5.7/6.47	138	35	16	1.62 ± 0.22	2.38 ± 0.26	0.036
120			49.6/58.4	6/6.47	177	32	13	0.07 ± 0.01	0.11 ± 0.02	0.051
97	Cystatin-B	P04080	12.11/11.2	5.6/6.96	76	55	5	0.65 ± 0.16	0.18 ± 0.02	0.018

MW – molecular weight (kDa); pI – isoelectric point; (–) Missing values due to unsuccessful identification.

Figure 2. Representative 2-DE profile of saliva analysed. Circles represent the spots differentially expressed between sensitive and low-sensitive groups.

MW – molecular weight (kDa); pI – isoelectric point.

Figure 3. Enzymatic activity of salivary α-amylase (U/min) in men (N = 46) and women (N = 41) with different sensitivity levels to sweet taste (mean ± SEM).

*Statistically significant differences: P < 0.05.

Figure 4. Representative Western blot analysis of cystatins S-SA-SN (a) and CA VI (b) in mixed saliva samples of individuals with different sensitivity levels to sweet taste (mean ± SEM).

*Statistically significant differences: P < 0.05.