Limits...
Large-scale phenotyping of an accurate genetic mouse model of JNCL identifies novel early pathology outside the central nervous system.

Staropoli JF, Haliw L, Biswas S, Garrett L, Hölter SM, Becker L, Skosyrski S, Da Silva-Buttkus P, Calzada-Wack J, Neff F, Rathkolb B, Rozman J, Schrewe A, Adler T, Puk O, Sun M, Favor J, Racz I, Bekeredjian R, Busch DH, Graw J, Klingenspor M, Klopstock T, Wolf E, Wurst W, Zimmer A, Lopez E, Harati H, Hill E, Krause DS, Guide J, Dragileva E, Gale E, Wheeler VC, Boustany RM, Brown DE, Breton S, Ruether K, Gailus-Durner V, Fuchs H, de Angelis MH, Cotman SL - PLoS ONE (2012)

Bottom Line: Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults.In a comprehensive blood analysis at 15-16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3(Δ) (ex7/8) mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis.Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3(Δ) (ex7/8) neonates, and to a greater extent in older animals.

View Article: PubMed Central - PubMed

Affiliation: Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America.

ABSTRACT
Cln3(Δex7/8) mice harbor the most common genetic defect causing juvenile neuronal ceroid lipofuscinosis (JNCL), an autosomal recessive disease involving seizures, visual, motor and cognitive decline, and premature death. Here, to more thoroughly investigate the manifestations of the common JNCL mutation, we performed a broad phenotyping study of Cln3(Δex7/8) mice. Homozygous Cln3(Δex7/8) mice, congenic on a C57BL/6N background, displayed subtle deficits in sensory and motor tasks at 10-14 weeks of age. Homozygous Cln3(Δex7/8) mice also displayed electroretinographic changes reflecting cone function deficits past 5 months of age and a progressive decline of retinal post-receptoral function. Metabolic analysis revealed increases in rectal body temperature and minimum oxygen consumption in 12-13 week old homozygous Cln3(Δex7/8) mice, which were also seen to a lesser extent in heterozygous Cln3(Δex7/8) mice. Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults. In a comprehensive blood analysis at 15-16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3(Δ) (ex7/8) mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis. Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3(Δ) (ex7/8) neonates, and to a greater extent in older animals. Early onset, severe vacuolation in clear cells of the epididymis of male homozygous Cln3(Δ) (ex7/8) mice was also observed. These data highlight additional organ systems in which to study CLN3 function, and early phenotypes have been established in homozygous Cln3(Δ) (ex7/8) mice that merit further study for JNCL biomarker development.

Show MeSH

Related in: MedlinePlus

Electroretinography of 16-month-old Cln3Δex7/8 mice. (A) Scotopic ERG traces are shown for 5-, 9-, and 16-month old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. The relative amplitudes of the a-wave do not dramatically differ between the wild-type and homozygous Cln3Δex7/8 mice. However, the b-wave is drastically reduced in aged homozygous Cln3Δex7/8 mice, compared to wild-type littermates. Thus, homozygous Cln3Δex7/8 mice exhibit an electronegative ERG at 16-months of age (b/a ratio = 1, versus b/a ratio = 2.4 in wild-type mice). (B) Photopic ERG traces, reflecting cone response, are shown for 5-, 9-, and 16-month-old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. There was a significant genotypic difference in the relative mean amplitudes already at 5 months of age.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3368842&req=5

pone-0038310-g002: Electroretinography of 16-month-old Cln3Δex7/8 mice. (A) Scotopic ERG traces are shown for 5-, 9-, and 16-month old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. The relative amplitudes of the a-wave do not dramatically differ between the wild-type and homozygous Cln3Δex7/8 mice. However, the b-wave is drastically reduced in aged homozygous Cln3Δex7/8 mice, compared to wild-type littermates. Thus, homozygous Cln3Δex7/8 mice exhibit an electronegative ERG at 16-months of age (b/a ratio = 1, versus b/a ratio = 2.4 in wild-type mice). (B) Photopic ERG traces, reflecting cone response, are shown for 5-, 9-, and 16-month-old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. There was a significant genotypic difference in the relative mean amplitudes already at 5 months of age.

Mentions: Study of retinal function in Cln3Δex7/8 mice has not previously been reported for any genetic background, but our previous morphological analysis of the retina from aged homozygous Cln3Δex7/8 mice outbred on the CD1 background indicated a low level cell loss within the retina in hypopigmented mice, without dramatic thinning of the retina [8]. Subsequent studies of the CD1 background mice indicated additional retinal degeneration genetic loci, independent of the Cln3 locus, leaving the precise details of retinal degeneration as a result of the Cln3Δex7/8 mutation in question (Ruether, unpublished data). Therefore, we sought to further evaluate the vision of aging Cln3?ex7/8 mice congenic on the C57BL/6N background by electroretinography (ERG) at 5, 9, and 16 months of age. The scotopic (dark-adapted) ERG reflecting rod function and, at higher stimulus strengths, mixed rod-cone function, shows a progressive decline of the b-wave amplitude of homozygous Cln3Δex7/8 mice, reaching statistical significance at an age of 9 months compared to wild-type littermates (Fig. 2A). At an age of 16 months the difference was profound. However, there was virtually no difference between a-wave amplitude at any of the ages. At 16 months of age, the b/a ratio for homozygous Cln3Δex7/8 mice was 1.0, indicating the a- and b-wave ERG components had the same amplitudes. In normal mice, the b/a wave ratio is typically greater than 1.6. By photopic (light-adapted) ERG, which primarily reflects cone function, amplitudes were already significantly reduced in homozygous Cln3Δex7/8 mice by the age of 5 months, compared to wild-type littermates, and further reduction in the amplitude measured in homozygous Cln3Δex7/8 mice was observed at 16 months of age (Fig. 2B). The a-wave of the ERG originates in the photoreceptor layer, while the b-wave emanates from lower order retinal cells, postsynaptic to the photoreceptors [33]. Therefore, the selective loss of the b-wave in homozygous Cln3Δex7/8 mice on the C57BL/6N background, indicates that there is primarily a loss of function in the postsynaptic retinal neurons.


Large-scale phenotyping of an accurate genetic mouse model of JNCL identifies novel early pathology outside the central nervous system.

Staropoli JF, Haliw L, Biswas S, Garrett L, Hölter SM, Becker L, Skosyrski S, Da Silva-Buttkus P, Calzada-Wack J, Neff F, Rathkolb B, Rozman J, Schrewe A, Adler T, Puk O, Sun M, Favor J, Racz I, Bekeredjian R, Busch DH, Graw J, Klingenspor M, Klopstock T, Wolf E, Wurst W, Zimmer A, Lopez E, Harati H, Hill E, Krause DS, Guide J, Dragileva E, Gale E, Wheeler VC, Boustany RM, Brown DE, Breton S, Ruether K, Gailus-Durner V, Fuchs H, de Angelis MH, Cotman SL - PLoS ONE (2012)

Electroretinography of 16-month-old Cln3Δex7/8 mice. (A) Scotopic ERG traces are shown for 5-, 9-, and 16-month old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. The relative amplitudes of the a-wave do not dramatically differ between the wild-type and homozygous Cln3Δex7/8 mice. However, the b-wave is drastically reduced in aged homozygous Cln3Δex7/8 mice, compared to wild-type littermates. Thus, homozygous Cln3Δex7/8 mice exhibit an electronegative ERG at 16-months of age (b/a ratio = 1, versus b/a ratio = 2.4 in wild-type mice). (B) Photopic ERG traces, reflecting cone response, are shown for 5-, 9-, and 16-month-old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. There was a significant genotypic difference in the relative mean amplitudes already at 5 months of age.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3368842&req=5

pone-0038310-g002: Electroretinography of 16-month-old Cln3Δex7/8 mice. (A) Scotopic ERG traces are shown for 5-, 9-, and 16-month old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. The relative amplitudes of the a-wave do not dramatically differ between the wild-type and homozygous Cln3Δex7/8 mice. However, the b-wave is drastically reduced in aged homozygous Cln3Δex7/8 mice, compared to wild-type littermates. Thus, homozygous Cln3Δex7/8 mice exhibit an electronegative ERG at 16-months of age (b/a ratio = 1, versus b/a ratio = 2.4 in wild-type mice). (B) Photopic ERG traces, reflecting cone response, are shown for 5-, 9-, and 16-month-old wild-type (Cln3+/+, black trace, n = 7) and homozygous Cln3Δex7/8 (Cln3Δex7/8/Δex7/8, red trace, n = 8) mice. There was a significant genotypic difference in the relative mean amplitudes already at 5 months of age.
Mentions: Study of retinal function in Cln3Δex7/8 mice has not previously been reported for any genetic background, but our previous morphological analysis of the retina from aged homozygous Cln3Δex7/8 mice outbred on the CD1 background indicated a low level cell loss within the retina in hypopigmented mice, without dramatic thinning of the retina [8]. Subsequent studies of the CD1 background mice indicated additional retinal degeneration genetic loci, independent of the Cln3 locus, leaving the precise details of retinal degeneration as a result of the Cln3Δex7/8 mutation in question (Ruether, unpublished data). Therefore, we sought to further evaluate the vision of aging Cln3?ex7/8 mice congenic on the C57BL/6N background by electroretinography (ERG) at 5, 9, and 16 months of age. The scotopic (dark-adapted) ERG reflecting rod function and, at higher stimulus strengths, mixed rod-cone function, shows a progressive decline of the b-wave amplitude of homozygous Cln3Δex7/8 mice, reaching statistical significance at an age of 9 months compared to wild-type littermates (Fig. 2A). At an age of 16 months the difference was profound. However, there was virtually no difference between a-wave amplitude at any of the ages. At 16 months of age, the b/a ratio for homozygous Cln3Δex7/8 mice was 1.0, indicating the a- and b-wave ERG components had the same amplitudes. In normal mice, the b/a wave ratio is typically greater than 1.6. By photopic (light-adapted) ERG, which primarily reflects cone function, amplitudes were already significantly reduced in homozygous Cln3Δex7/8 mice by the age of 5 months, compared to wild-type littermates, and further reduction in the amplitude measured in homozygous Cln3Δex7/8 mice was observed at 16 months of age (Fig. 2B). The a-wave of the ERG originates in the photoreceptor layer, while the b-wave emanates from lower order retinal cells, postsynaptic to the photoreceptors [33]. Therefore, the selective loss of the b-wave in homozygous Cln3Δex7/8 mice on the C57BL/6N background, indicates that there is primarily a loss of function in the postsynaptic retinal neurons.

Bottom Line: Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults.In a comprehensive blood analysis at 15-16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3(Δ) (ex7/8) mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis.Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3(Δ) (ex7/8) neonates, and to a greater extent in older animals.

View Article: PubMed Central - PubMed

Affiliation: Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Boston, Massachusetts, United States of America.

ABSTRACT
Cln3(Δex7/8) mice harbor the most common genetic defect causing juvenile neuronal ceroid lipofuscinosis (JNCL), an autosomal recessive disease involving seizures, visual, motor and cognitive decline, and premature death. Here, to more thoroughly investigate the manifestations of the common JNCL mutation, we performed a broad phenotyping study of Cln3(Δex7/8) mice. Homozygous Cln3(Δex7/8) mice, congenic on a C57BL/6N background, displayed subtle deficits in sensory and motor tasks at 10-14 weeks of age. Homozygous Cln3(Δex7/8) mice also displayed electroretinographic changes reflecting cone function deficits past 5 months of age and a progressive decline of retinal post-receptoral function. Metabolic analysis revealed increases in rectal body temperature and minimum oxygen consumption in 12-13 week old homozygous Cln3(Δex7/8) mice, which were also seen to a lesser extent in heterozygous Cln3(Δex7/8) mice. Heart weight was slightly increased at 20 weeks of age, but no significant differences were observed in cardiac function in young adults. In a comprehensive blood analysis at 15-16 weeks of age, serum ferritin concentrations, mean corpuscular volume of red blood cells (MCV), and reticulocyte counts were reproducibly increased in homozygous Cln3(Δ) (ex7/8) mice, and male homozygotes had a relative T-cell deficiency, suggesting alterations in hematopoiesis. Finally, consistent with findings in JNCL patients, vacuolated peripheral blood lymphocytes were observed in homozygous Cln3(Δ) (ex7/8) neonates, and to a greater extent in older animals. Early onset, severe vacuolation in clear cells of the epididymis of male homozygous Cln3(Δ) (ex7/8) mice was also observed. These data highlight additional organ systems in which to study CLN3 function, and early phenotypes have been established in homozygous Cln3(Δ) (ex7/8) mice that merit further study for JNCL biomarker development.

Show MeSH
Related in: MedlinePlus