Evaluation of drug-induced tissue injury by measuring alanine aminotransferase (ALT) activity in silkworm hemolymph

Abstract

BackgroundOur previous studies suggest silkworms can be used as model animals instead of mammals in pharmacologic studies to develop novel therapeutic medicines. We examined the usefulness of the silkworm larvae Bombyx mori as an animal model for evaluating tissue injury induced by various cytotoxic drugs. Drugs that induce hepatotoxic effects in mammals were injected into the silkworm hemocoel, and alanine aminotransferase (ALT) activity was measured in the hemolymph 1 day later.ResultsInjection of CCl4 into the hemocoel led to an increase in ALT activity. The increase in ALT activity was attenuated by pretreatment with N-acetyl-L-cysteine. Injection of benzoic acid derivatives, ferric sulfate, sodium valproate, tetracycline, amiodarone hydrochloride, methyldopa, ketoconazole, pemoline (Betanamin), N-nitroso-fenfluramine, and D-galactosamine also increased ALT activity.ConclusionsThese findings indicate that silkworms are useful for evaluating the effects of chemicals that induce tissue injury in mammals.

Larval Exposure to Chlorpyrifos Affects Nutritional Physiology and Induces Genotoxicity in Silkworm Philosamia ricini (Lepidoptera: Saturniidae)

“…ALT assay was performed following the method of Inagaki et al (2012). Ten milli liter Tof the supernatant was mixed with 550 μl of the reaction mixture (0.5 M L-alanine, 0.2 mM NADH, 1.3 U/ml lactate dehydrogenase and 0.9 mg/ml of BSA) and vortexed.…”

A hyperglycemic silkworm model for evaluating hypoglycemic activity of Rehmanniae Radix, an herbal medicine

“…We have proposed that silkworms are useful for evaluation of therapeutic effects and toxicities of drug candidates (3)(4)(5)(6). We previously reported that therapeutic effects and pharmacokinetics of chemicals, such as antibacterial, anti-fungal, anti-viral drugs, in silkworm were similar to that in mammals (3,4,(7)(8)(9)(10).…”

Using silkworms to establish alternative animal models for evaluation of drug-induced tissue injury

“…The ALT level in the hemolymph of silkworm larvae rose with injection of CCl 4 , which is generally used as a model compound for examination of hepatotoxic effects in mammals (20). Elevated ALT activity in the hemolymph of silkworms has been induced with various hepatotoxic chemicals such as acetaminophen, tetracycline, ketoconazole, and D-galactosamine (20). These results suggest that the silkworm can be used to evaluate hepatotoxicity by measuring the level of ALT activity in hemolymph.…”

“…In a previous study by the current authors, ALT activity was measured in the hemolymph of silkworms using usual enzymatic methods (20). The ALT level in the hemolymph of silkworm larvae rose with injection of CCl 4 , which is generally used as a model compound for examination of hepatotoxic effects in mammals (20). Elevated ALT activity in the hemolymph of silkworms has been induced with various hepatotoxic chemicals such as acetaminophen, tetracycline, ketoconazole, and D-galactosamine (20).…”

“…Therefore, an alternative animal model that allows evaluation of the level of ALT activity needs to be established. In a previous study by the current authors, ALT activity was measured in the hemolymph of silkworms using usual enzymatic methods (20). The ALT level in the hemolymph of silkworm larvae rose with injection of CCl 4 , which is generally used as a model compound for examination of hepatotoxic effects in mammals (20).…”