. Author manuscript; available in PMC: 2022 Oct 4.

Published in final edited form as: Pediatr Res. 2021 Oct 8;92(2):415–423. doi: 10.1038/s41390-021-01747-5

Table 2:

Reduction of region-specific neuropathology by a 5-dose Azithromycin (AZ) Regimen vs. a 3-dose Regimen, after LPS-amplified Hypoxia-Ischemia (LPS+HI) ^a or Pam₃CSK₄-amplified Hypoxia-Ischemia (PAM+HI) ^b.

a. LPS-amplified HI ^a
Treatment	Side	P35 Volume ^c (mean ±SD, mm³) and %Intact Right ^c (mean ±SD)
		Cortex		Striatum		Hippocampus		Other ^d		Hemisphere
		Volume	%Intact	Volume	%Intact	Volume	%Intact	Volume	%Intact	Volume	%Intact
Saline	Left	118 ±6		36 ±3		13 ±3		141 ±10		287 ±81
	Right	79±30	62±29	20 ±8	53 ±28	10 ±3	72 ±27	115 ±24	76 ±25	209 ±83	67 ±25
AZ*3	Left	126 ±9		37 ±3		16±2		151 ±9		288±114
	Right	114±11 ^*	80 ±32	30±7 ^*	69±30	13 ±3	70 ±29	136±11 ^*	79 ±32	256 ±103	78 ±31
AZ*5	Left	124±8		37 ±4		15±2		148 ±8		304 ±83
	Right	116 ±8 ^*	87±24 ^†	32 ±5 ^*	81±24 ^†	13±2 ^*	80 ±23	139±14 ^*	88 ±25	281 ±79	87 ±24 ^‡
b. PAM-amplified HI ^b
Treatment	Side	P35 Volume ^c (mean ±SD, mm³) and %Intact Right ^c (mean ±SD)
		Cortex		Striatum		Hippocampus		Other ^d		Hemisphere
		Volume	%Intact	Volume	%Intact	Volume	%Intact	Volume	%Intact	Volume	%Intact
Saline	Left	110 ±9		40 ±3		17 ±2		129 ±11		222 ±138
	Right	66±14	45±30	18 ±4	34 ±22	11 ±3	48 ±31	97 ±17	56 ±35	144 ±93	48 ±31
AZ*3	Left	110 ±18		39 ±8		17 ±4		129 ±24		295 ±52
	Right	92 ±24	83 ±9 ^†	29 ±9 ^*	72±10 ^†	13 ±3	81 ±10 ^†	117 ±28	90 ±8	251 ±63	84 ±8 ^‡
AZ*5	Left	112±18		39 ±8		16±2		128 ±19		258±112
	Right	97 ±22 ^*	75±31	31 ±9 ^*	68±29 ^†	14±2	75 ±33	127±24	87 ±35	236 ±108	79 ±32 ^‡

^a:

LPS+HI: Lipopolysaccharide (LPS, 0.05 mg/kg) was injected intraperitoneally (i.p.), 2.5 h prior to right carotid artery ligation in seven-day-old (P7) rats, and 1.5 h later exposure to 50 min 8% O₂ started (see Methods). Treatment began with i.p. injections 2 h after HI (n=15–16/group): AZ 3-dose (AZ*3: 45, 22.5, 22.5 mg/kg/dose at 2, 24 and 48 h) vs. 5-dose (AZ*5: 45, 22.5, 22.5, 22.5, 22.5 mg/kg/dose, 2, 24, 48, 72 and 96 h) vs. saline controls (5 injections, same times as AZ*5).

^b:

PAM+HI: The synthetic lipopeptide TLR2 agonist Pam₃Cys-Ser-(Lys)₄ (PAM, 0.5 mg/kg) was injected i.p. 4.5 h prior to right carotid artery ligation in seven-day-old (P7) rats, and 1.5 h later exposure to 60 min 8% O₂ started (see Methods). Treatment regimens (n=8/group) were the same as in LPS+HI.

^c:

Bilateral regional and hemisphere volumes were calculated on postnatal day 35 (P35) from bilateral regional area measurements of intact-staining tissue in regularly spaced coronal sections (see Methods). Regional volumes, expressed as means ± SD, were compared by RM ANOVA, factoring region and treatment, with region as repeated measure. %Intact tissue on the right (R), compared to non-lesioned left (L), a measure of damage severity, was calculated for each region (and hemisphere) from bilateral volumes, as 100*(R/L); animals that die before P35 are assigned a volume of 0 and a %intact value of 0.

^d:

“Other” represents all other hemisphere tissue that was not designated as either cortex, striatum or hippocampus, and includes both grey matter regions (e.g. thalamus, globus pallidus, septum) and white matter tracts.

For LPS+HI (a.)

Right regional volumes were greater in AZ*5 than in controls for all 4 regions, and were greater in AZ*3 than controls for cortex, striatum and “other” (p<0.0001 overall by repeated measures ANOVA factoring treatment and region, with p<0.05 Tukey multiple comparison test for within-region comparisons).

^†

%intact R was greater in cortex and striatum in AZ*5 than in controls, by post-hoc testing (p<0.05, Tukey multiple comparison test).

^‡

%intact R hemisphere was greater in AZ*5 than in controls (p<0.05 Kruskal Wallis with Dunn’s multiple comparisons test).

For PAM+HI (b.)

Right regional volumes were greater in AZ*5 than in controls for cortex and striatum, and were greater in AZ*3 than controls for striatum (p<0.05 overall by repeated measures ANOVA factoring treatment and region, with p<0.05 Tukey post-hoc multiple comparison test for within-region comparisons). There was no significant difference in mean R volumes between AZ*3 and AZ*5.

^†

%intact R was greater in cortex, striatum and hippocampus in AZ*3, and greater in striatum in AZ*5 than in controls, by post-hoc testing (p<0.05, Tukey multiple comparison test).

^‡

%intact R hemisphere was greater in AZ*3 and AZ*5 than in controls (p<0.05 Kruskal Wallis with Dunn’s multiple comparisons test).