Limits...
Oxidative Stress in Caenorhabditis elegans: Protective Effects of Spartin.

Truong T, Karlinski ZA, O'Hara C, Cabe M, Kim H, Bakowska JC - PLoS ONE (2015)

Bottom Line: These results suggest an age-dependent decline in motor function in mutant animals.In the behavioral assays, spg-20 mutant animals showed a significant decrease in both crawling speed and thrashing frequency compared with wild-type animals.These data suggest that the protein F57B10.9/SPG-20 might have a protective role against oxidative stress.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois, United States of America.

ABSTRACT
Troyer syndrome is caused by a mutation in the SPG20 gene, which results in complete loss of expression of the protein spartin. We generated a genetic model of Troyer syndrome in worms to explore the locomotor consequences of a mutation of the Caenorhabditis elegans SPG20 orthologue, F57B10.9, also known as spg-20. Spg-20 mutants showed decreased length, crawling speed, and thrashing frequency, and had a shorter lifespan than wild-type animals. These results suggest an age-dependent decline in motor function in mutant animals. The drug paraquat was used to induce oxidative stress for 4 days in the animals. We measured survival rate and examined locomotion by measuring crawling speed and thrashing frequency. After 4 days of paraquat exposure, 77% of wild-type animals survived, but only 38% of spg-20 mutant animals survived. Conversely, animals overexpressing spg-20 had a survival rate of 95%. We also tested lifespan after a 1 hour exposure to sodium azide. After a 24 hour recovery period, 87% of wild type animals survived, 57% of spg-20 mutant animals survived, and 82% of animals overexpressing spg-20 survived. In the behavioral assays, spg-20 mutant animals showed a significant decrease in both crawling speed and thrashing frequency compared with wild-type animals. Importantly, the locomotor phenotype for both crawling and thrashing was rescued in animals overexpressing spg-20. The animals overexpressing spg-20 had crawling speeds and thrashing frequencies similar to those of wild-type animals. These data suggest that the protein F57B10.9/SPG-20 might have a protective role against oxidative stress.

No MeSH data available.


Related in: MedlinePlus

spg-20 mutant animals exhibited reduced locomotor function and shortened lifespan.(A) Day 1-stage adults were used to measure average length of wild-type (WT) and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had diminished growth compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (B) Day 1-stage adults were used to measure average speed of WT and spg-20(tm5514) mutant animals on NGM plates without food. spg-20(tm5514) mutant animals had reduced speed compared with WT animals (*p<0.05). Speed was quantified by video analysis, as described in Materials and Methods. Error bars represent SEM. Two-tailed Student t test; n > 30. (C) Day 1-stage adults were used to measure the thrashing frequency (body bends per second) of WT and spg-20(tm5514) mutant animals in M9 liquid via video analysis, as described in Materials and Methods. spg-20(tm5514) mutant animals had a reduced thrashing rate compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (D) Fractional survival of WT and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had a shorter lifespan than WT animals (p<0.0001). The L4 stage was set as Day 0, and the animals were maintained on OP50 at 20°C for 29 days. Error bars represent SEM. Kaplan-Meier method; n > 30.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4482654&req=5

pone.0130455.g003: spg-20 mutant animals exhibited reduced locomotor function and shortened lifespan.(A) Day 1-stage adults were used to measure average length of wild-type (WT) and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had diminished growth compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (B) Day 1-stage adults were used to measure average speed of WT and spg-20(tm5514) mutant animals on NGM plates without food. spg-20(tm5514) mutant animals had reduced speed compared with WT animals (*p<0.05). Speed was quantified by video analysis, as described in Materials and Methods. Error bars represent SEM. Two-tailed Student t test; n > 30. (C) Day 1-stage adults were used to measure the thrashing frequency (body bends per second) of WT and spg-20(tm5514) mutant animals in M9 liquid via video analysis, as described in Materials and Methods. spg-20(tm5514) mutant animals had a reduced thrashing rate compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (D) Fractional survival of WT and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had a shorter lifespan than WT animals (p<0.0001). The L4 stage was set as Day 0, and the animals were maintained on OP50 at 20°C for 29 days. Error bars represent SEM. Kaplan-Meier method; n > 30.

Mentions: To identify differences in phenotypes between spg-20(tm5514) mutant animals and wild-type animals, we measured the length of Day 1-stage adults. Wild-type animals grew to an average length of 1.22 mm (± 0.036 SEM), and spg-20(tm5514) mutants grew to an average length of 1.10 mm (± 0.016 SEM). On average, spg-20(tm5514) mutant animals had diminished length compared with wild-type animals (p<0.05) (Fig 3A). Representative images can be found in S1 Fig. To determine whether spg-20 mutants lose locomotor function, we quantified the average speed and thrashing frequency of wild-type and spg-20(tm5514) animals. Videos of individual Day 1-stage adults were recorded and coded for both crawling movement across an agar surface and swimming motion in liquid. The videos were analyzed using the open-source wrMTrck plugin for ImageJ. Wild-type animals displayed an average speed of 0.18 mm/s (±0.0067 SEM) on agar, whereas spg-20(tm5514) animals displayed an average speed of 0.15 mm/s (±0.0096 SEM), a 15% decrease in speed compared to wild-type (p<0.05) (Fig 3B). The frequency of lateral swimming movement in liquid, also known as thrashing, is another conventional method used to characterize locomotor function in C. elegans. We conducted an automated assessment of the thrashing rate for wild-type and spg-20(tm5514) mutant animals. Wild-type animals displayed an average of 2.23 body bends per second (±0.060 SEM), whereas spg-20(tm5514) mutant animals displayed an average of 1.96 body bends per second (±0.084 SEM). Overall, mutant animals exhibited 10% fewer body bends per second than wild-type animals (p<0.05) (Fig 3C). Because the reduced locomotor function might be indicative of aging [18], we decided to measure the lifespan of wild-type and spg-20 mutant animals. Animals did not exhibit differences in survival until after the sixth day. All wild-type animals survived until the eighth day, but animals with the spg-20(tm5514) mutation began dying after the sixth day. Wild-type animals survived up to 29 days, but spg-20(tm5514) mutant animals survived only up to 19 days (p<0.0001) (Fig 3D). The survival data were analyzed using the Kaplan-Meier method, which revealed significant differences between the lifespan of spg-20 mutant and wild-type animals.


Oxidative Stress in Caenorhabditis elegans: Protective Effects of Spartin.

Truong T, Karlinski ZA, O'Hara C, Cabe M, Kim H, Bakowska JC - PLoS ONE (2015)

spg-20 mutant animals exhibited reduced locomotor function and shortened lifespan.(A) Day 1-stage adults were used to measure average length of wild-type (WT) and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had diminished growth compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (B) Day 1-stage adults were used to measure average speed of WT and spg-20(tm5514) mutant animals on NGM plates without food. spg-20(tm5514) mutant animals had reduced speed compared with WT animals (*p<0.05). Speed was quantified by video analysis, as described in Materials and Methods. Error bars represent SEM. Two-tailed Student t test; n > 30. (C) Day 1-stage adults were used to measure the thrashing frequency (body bends per second) of WT and spg-20(tm5514) mutant animals in M9 liquid via video analysis, as described in Materials and Methods. spg-20(tm5514) mutant animals had a reduced thrashing rate compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (D) Fractional survival of WT and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had a shorter lifespan than WT animals (p<0.0001). The L4 stage was set as Day 0, and the animals were maintained on OP50 at 20°C for 29 days. Error bars represent SEM. Kaplan-Meier method; n > 30.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482654&req=5

pone.0130455.g003: spg-20 mutant animals exhibited reduced locomotor function and shortened lifespan.(A) Day 1-stage adults were used to measure average length of wild-type (WT) and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had diminished growth compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (B) Day 1-stage adults were used to measure average speed of WT and spg-20(tm5514) mutant animals on NGM plates without food. spg-20(tm5514) mutant animals had reduced speed compared with WT animals (*p<0.05). Speed was quantified by video analysis, as described in Materials and Methods. Error bars represent SEM. Two-tailed Student t test; n > 30. (C) Day 1-stage adults were used to measure the thrashing frequency (body bends per second) of WT and spg-20(tm5514) mutant animals in M9 liquid via video analysis, as described in Materials and Methods. spg-20(tm5514) mutant animals had a reduced thrashing rate compared with WT animals (*p<0.05). Error bars represent SEM. Two-tailed Student t test; n > 30. (D) Fractional survival of WT and spg-20(tm5514) mutant animals. spg-20(tm5514) mutant animals had a shorter lifespan than WT animals (p<0.0001). The L4 stage was set as Day 0, and the animals were maintained on OP50 at 20°C for 29 days. Error bars represent SEM. Kaplan-Meier method; n > 30.
Mentions: To identify differences in phenotypes between spg-20(tm5514) mutant animals and wild-type animals, we measured the length of Day 1-stage adults. Wild-type animals grew to an average length of 1.22 mm (± 0.036 SEM), and spg-20(tm5514) mutants grew to an average length of 1.10 mm (± 0.016 SEM). On average, spg-20(tm5514) mutant animals had diminished length compared with wild-type animals (p<0.05) (Fig 3A). Representative images can be found in S1 Fig. To determine whether spg-20 mutants lose locomotor function, we quantified the average speed and thrashing frequency of wild-type and spg-20(tm5514) animals. Videos of individual Day 1-stage adults were recorded and coded for both crawling movement across an agar surface and swimming motion in liquid. The videos were analyzed using the open-source wrMTrck plugin for ImageJ. Wild-type animals displayed an average speed of 0.18 mm/s (±0.0067 SEM) on agar, whereas spg-20(tm5514) animals displayed an average speed of 0.15 mm/s (±0.0096 SEM), a 15% decrease in speed compared to wild-type (p<0.05) (Fig 3B). The frequency of lateral swimming movement in liquid, also known as thrashing, is another conventional method used to characterize locomotor function in C. elegans. We conducted an automated assessment of the thrashing rate for wild-type and spg-20(tm5514) mutant animals. Wild-type animals displayed an average of 2.23 body bends per second (±0.060 SEM), whereas spg-20(tm5514) mutant animals displayed an average of 1.96 body bends per second (±0.084 SEM). Overall, mutant animals exhibited 10% fewer body bends per second than wild-type animals (p<0.05) (Fig 3C). Because the reduced locomotor function might be indicative of aging [18], we decided to measure the lifespan of wild-type and spg-20 mutant animals. Animals did not exhibit differences in survival until after the sixth day. All wild-type animals survived until the eighth day, but animals with the spg-20(tm5514) mutation began dying after the sixth day. Wild-type animals survived up to 29 days, but spg-20(tm5514) mutant animals survived only up to 19 days (p<0.0001) (Fig 3D). The survival data were analyzed using the Kaplan-Meier method, which revealed significant differences between the lifespan of spg-20 mutant and wild-type animals.

Bottom Line: These results suggest an age-dependent decline in motor function in mutant animals.In the behavioral assays, spg-20 mutant animals showed a significant decrease in both crawling speed and thrashing frequency compared with wild-type animals.These data suggest that the protein F57B10.9/SPG-20 might have a protective role against oxidative stress.

View Article: PubMed Central - PubMed

Affiliation: Department of Molecular Pharmacology and Therapeutics, Loyola University Chicago, Maywood, Illinois, United States of America.

ABSTRACT
Troyer syndrome is caused by a mutation in the SPG20 gene, which results in complete loss of expression of the protein spartin. We generated a genetic model of Troyer syndrome in worms to explore the locomotor consequences of a mutation of the Caenorhabditis elegans SPG20 orthologue, F57B10.9, also known as spg-20. Spg-20 mutants showed decreased length, crawling speed, and thrashing frequency, and had a shorter lifespan than wild-type animals. These results suggest an age-dependent decline in motor function in mutant animals. The drug paraquat was used to induce oxidative stress for 4 days in the animals. We measured survival rate and examined locomotion by measuring crawling speed and thrashing frequency. After 4 days of paraquat exposure, 77% of wild-type animals survived, but only 38% of spg-20 mutant animals survived. Conversely, animals overexpressing spg-20 had a survival rate of 95%. We also tested lifespan after a 1 hour exposure to sodium azide. After a 24 hour recovery period, 87% of wild type animals survived, 57% of spg-20 mutant animals survived, and 82% of animals overexpressing spg-20 survived. In the behavioral assays, spg-20 mutant animals showed a significant decrease in both crawling speed and thrashing frequency compared with wild-type animals. Importantly, the locomotor phenotype for both crawling and thrashing was rescued in animals overexpressing spg-20. The animals overexpressing spg-20 had crawling speeds and thrashing frequencies similar to those of wild-type animals. These data suggest that the protein F57B10.9/SPG-20 might have a protective role against oxidative stress.

No MeSH data available.


Related in: MedlinePlus