Effect of carnosine, aminoguanidine, and aspirin drops on the prevention of cataracts in diabetic rats.

Yan H, Guo Y, Zhang J, Ding Z, Ha W, Harding JJ

Molecular vision11 Dec 2008Cited by 36 (Europe PMC)

PMID19081783PMCIDPMC2600521PepBankPUB-19081783

Summary

PurposeTo investigate the effect of carnosine (CA), aminoguanidine (AG), and aspirin (ASA) drops, all inhibitors of glycation, on the development of diabetic cataract in rat.MethodsRats were made diabetic with streptozotocin, and based on the level of plasma glucose, they were assigned as non-diabetic rats (14 mmol/l plasma glucose). Animals in the treated groups received CA, AG, and ASA as drops to the left eyes starting from the day of streptozotocin injection. Progression of lens opacification was recorded using the slit lamp at regular time intervals. All the rats were killed after the week 13, and the levels of advanced glycation end products (AGE), glutathione reductase (GR), catalase (CAT), and glutathione (GSH) were determined.ResultsLens opacification progressed in a biphasic manner in the diabetic rats, an initial slow increase during the first eight weeks of diabetes followed by a steep increase in the next five weeks. Carnosine treatment delayed the progression of cataracts in diabetic rats, and the delay was statistically significant on the fourth week of diabetes (p<0.05, when compared with untreated moderately diabetic rats). A decrease in the antioxidant enzymes of CAT and the level of GSH was found in the lens of the untreated diabetic rats at 13 weeks after injection. Some protection was provided in the treated eyes. The level of glycation in the untreated diabetic rats was significantly higher than that in the normal rats (p<0.001). After treatment with CA, AG, and ASA, those diabetic rats had a lower level of glycated lens protein compared to the untreated diabetic rats (p<0.001).ConclusionsThese results thus suggest that the effect of CA, AG, and ASA is indeed inhibition of the formation of AGEs. However, the effect of CA, AG, and ASA is overwhelmed by the excessive accumulation of AGEs in the severely diabetic rats. CA compared with AG and ASA treatment can delay the progression of lens opacification in the diabetic rats only during the earlier stages. It also protects against the inactivation of enzymes.

CC BYText from Europe PMC. Highlighted sentences are the source of results.

Results from this study2

2 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Efficacy outcome
In diabetic rats, carnosine delayed cataract progression versus untreated moderately diabetic rats, significantly at the fourth week.
In plain wordsIn rats with diabetes, carnosine delayed cataract progression compared with untreated moderately diabetic rats.
Peptide
L-carnosine
Outcome
DecreaseCataract progression
Study
ratn: not reported in source
streptozotocin-induced diabetes
Comparator
untreated moderately diabetic rats
Outcome group
Vision and retina · Eye
Studied dose
Dose not stated · eye dropsAs given in this study (rat).
Source sentences
Summary
Carnosine treatment delayed the progression of cataracts in diabetic rats, and the delay was statistically significant on the fourth week of diabetes (p<0.05, when compared with untreated moderately diabetic rats).
2 context sentences(design, population, supporting numbers)
Summary · context
Rats were made diabetic with streptozotocin, and based on the level of plasma glucose, they were assigned as non-diabetic rats (14 mmol/l plasma glucose).
Summary · context
Animals in the treated groups received CA, AG, and ASA as drops to the left eyes starting from the day of streptozotocin injection.
Show in the study text Report a problemFND-1908178301
02AnimalAnimal study (in vivo)Efficacy outcome
In diabetic rats, carnosine treatment lowered glycated lens protein versus untreated diabetic rats.
In plain wordsIn rats with diabetes, carnosine lowered glycated lens protein compared with untreated diabetic rats.
Peptide
L-carnosine
Outcome
DecreaseGlycated lens protein
Study
ratn: not reported in source
streptozotocin-induced diabetes
Comparator
untreated diabetic rats
Outcome group
Protein and amino acid metabolism · Eye
Studied dose
Dose not stated · eye dropsAs given in this study (rat).
Source sentences
Summary
After treatment with CA, AG, and ASA, those diabetic rats had a lower level of glycated lens protein compared to the untreated diabetic rats (p<0.001).
2 context sentences(design, population, supporting numbers)
Summary · context
Rats were made diabetic with streptozotocin, and based on the level of plasma glucose, they were assigned as non-diabetic rats (14 mmol/l plasma glucose).
Summary · context
Animals in the treated groups received CA, AG, and ASA as drops to the left eyes starting from the day of streptozotocin injection.
Show in the study text Report a problemFND-1908178302

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Version history

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Version 2Current
27 Oct 2026, 18:20 UTC
Study results updated
Version 1
27 Oct 2026, 16:32 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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