Table 3.

Select polar lipid species from myelin extracted from the corpus callosum of heterozygous dogs (CTL, n = 4), untreated dogs affected with mucopolysaccharidosis type I (MPS, n = 4) and MPS I dogs treated with recombinant human alpha-l-iduronidase into the cerebrospinal fluid every three months from age 4m to 21m (MTr, N = 4). Data are expressed as mean ± SD nmol/mg protein. PC, phosphatidylcholine; SM, sphingomyelin; DSM, dihydrosphingomyelin; PS, phosphatidylserine; PI, phosphatidylinositol; PA, phosphatidic acid; e, ether-linked. (A) Polar lipid species that were low in affected dogs despite treatment (P < 0.05 for overall ANOVA, and Bonferroni-adjusted P < 0.05 for t-tests comparing CTL vs. MPS and CTL vs. MTr). SM, ePC, PS, and ePS species comprise the majority. Only one PC species remained significantly low with treatment. (B) Polar lipid species that were low in MPS, but were not significantly low in MTr dogs (P < 0.05 for overall ANOVA, and Bonferroni-adjusted P < 0.05 for t-test comparing CTL vs. MPS, and no significant difference between CTL vs. MTr).

(A) Species significantly low in affected dogs even with treatment				(B) Species low in affected dogs, but improved (not significantly low) with treatment
	CTL	MPS	MTr		CTL	MPS I	MTr
PC 34:4	0.0792 ± 0.0417	0.0134 ± 0.0090	0.0250 ± 0.0096	PC 36:1	147.2 ± 22.0	96.3 ± 16.0	127.3 ± 3.3
SM 22:0	30.0 ± 8.6	9.9 ± 4.1	13.8 ± 5.1	PC 38:3	4.19 ± 0.48	3.25 ± 0.36	4.13 ± 0.19
SM 24:0	152 ± 30	90 ± 16	94 ± 5	PC 40:2	5.95 ± 0.79	4.23 ± 0.98	4.72 ± 0.43
SM 24:1	294 ± 33	192 ± 31	185 ± 15	PC 42:11	0.154 ± 0.050	0.045 ± 0.021	0.096 ± 0.060
ePC 34:2	8.37 ± 1.75	3.87 ± 0.58	5.10 ± 1.56	DSM 16:0	2.59 ± 1.06	0.862 ± 0.203	1.93 ± 0.47
ePC 34:1	30.5 ± 8.3	15.8 ± 1.8	18.2 ± 4.1	SM 22:1	25.4 ± 6.4	13.2 ± 1.5	16.9 ± 2.9
ePC 36:3	7.88 ± 2.16	3.37 ± 0.45	4.69 ± 0.61	ePC 32:2	0.238 ± 0.042	0.097 ± 0.048	0.238 ± 0.060
ePC 36:2	8.67 ± 2.05	3.97 ± 0.73	4.98 ± 0.48	ePC 32:1	3.18 ± 0.57	1.88 ± 0.31	2.40 ± 0.55
ePC 36:1	10.21 ± 1.32	6.28 ± 0.81	7.19 ± 0.04	ePC 36:4	1.51 ± 0.64	0.62 ± 0.05	1.0 ± 0.2
ePC 38:3	1.61 ± 0.39	0.70 ± 0.23	0.84 ± 0.08	ePC 38:4	1.38 ± 0.48	0.71 ± 0.03	0.84 ± 0.12
ePC 38:2	4.11 ± 0.62	2.25 ± 0.39	2.47 ± 0.24	PE 38:0/ePE 40:7	1.30 ± 0.31	0.826 ± 0.216	1.25 ± 0.09
ePC 38:1	5.90 ± 0.28	3.30 ± 0.65	3.60 ± 0.28	ePE 34:2	4.69 ± 0.76	3.01 ± 0.38	3.96 ± 0.81
ePC 40:3	0.892 ± 0.254	0.436 ± 0.106	0.508 ± 0.084	ePE 36:5	0.292 ± 0.119	0.119 ± 0.021	0.246 ± 0.061
ePC 40:2	5.65 ± 0.16	3.59 ± 0.53	3.33 ± 0.59	ePE 36:3	10.6 ± 0.9	6.7 ± 0.9	8.9 ± 1.7
PS 36:1	317 ± 37	193 ± 44	228 ± 20	ePE 36:2	3.60 ± 0.71	2.37 ± 0.27	2.85 ± 0.22
PS 38:2	15.8 ± 3.3	9.4 ± 2.0	10.2 ± 0.6	ePE 38:3	3.72 ± 0.33	2.38 ± 0.31	2.84 ± 0.65
PS 38:1	14.2 ± 2.6	7.4 ± 1.2	7.1 ± 1.2	PI 34:1	4.08 ± 1.17	2.07 ± 0.68	2.84 ± 0.40
PS 40:8	0.521 ± 0.060	0.227 ± 0.119	0.254 ± 0.104	PI 36:1	2.25 ± 0.60	1.00 ± 0.37	1.84 ± 0.49
PS 40:2	4.21 ± 0.99	2.67 ± 0.58	2.48 ± 0.20	PS 36:2	38.4 ± 6.2	25.5 ± 6.6	27.6 ± 2.1
PS 40:1	2.93 ± 0.53	1.39 ± 0.13	1.37 ± 0.20	PS 42:11	0.279 ± 0.042	0.104 ± 0.069	0.200 ± 0.053
PS 42:8	0.704 ± 0.085	0.412 ± 0.097	0.383 ± 0.056	PA 36:3	0.667 ± 0.064	0.481 ± 0.079	0.779 ± 0.052
ePS 38:2	1.24 ± 0.19	0.69 ± 0.21	0.67 ± 0.10	ePS 36:1	2.70 ± 0.22	1.74 ± 0.47	2.06 ± 0.22
ePS 38:1	2.94 ± 0.56	1.74 ± 0.36	1.57 ± 0.34	ePS 38:6	0.38 ± 0.04	0.15 ± 0.10	0.34 ± 0.07
ePS 40:2	0.658 ± 0.148	0.310 ± 0.130	0.375 ± 0.032	ePS 38:3	0.18 ± 0.03	0.08 ± 0.05	0.14 ± 0.04

Note: Although species in panel B may be considered improved as defined by statistical testing, the degree of improvement in many species still appears incomplete.