JPS643167B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the use of N-acetylcysteine as an anti-cataract agent. N-acetylcysteine is obtained by directly acetylating cysteine or by acetylating cystine and then reducing it, and is generally a colorless needle-shaped crystal with a melting point of 109-110°C. This compound is used as an expectorant for bronchial asthma and is also known as a collagenase inhibitor. As a result of repeated research into substances that have anti-cataract effects, the present inventors discovered that N-acetylcysteine has this effect, leading to the completion of the present invention. Cataract is a condition in which the crystalline lens of the eye becomes cloudy and reduces visual acuity, and it occurs not only in humans but also in other mammals. Although the cause has not yet been determined, it is known to occur in experimental animals when naphthalene, alloxan, galactose, dinitrophenol, etc. are administered. That is, when naphthalene is orally administered to rabbits, vacuoles, which are a precursor to cataracts, are first formed within the lens, and at that point a decrease in the amount of reduced glutathione within the lens is observed. However, it was found that when N-acetylcysteine was administered to animals in advance, the formation of vacuoles in the lens due to the administration of naphthalene was prevented, and the amount of reduced glutaotine was hardly reduced compared to the control. The present invention is an anti-cataract agent consisting of or containing N-acetylcysteine. N-acetylcysteine can be administered orally or parenterally for the purpose of preventing the development or progression of cataracts. It can be administered orally, for example, as a tablet, pill, capsule, granule, or powder; parenterally, it can be administered, for example, as a subcutaneous, intramuscular, or intravenous injection solution. The above formulations can be prepared by conventional methods. For example, this compound contains starch, lactose,
It can be mixed with excipients such as and a suitable lubricant such as magnesium stearate and compressed to obtain tablets for internal use, or dissolved in distilled water and neutralized with sodium carbonate or sodium hydroxide for injection. The agent can also be adjusted. This compound has almost no toxicity, with acute toxicity _LD50 in mice of 1.2g/Kg for intravenous injection and 8.8g/Kg for oral administration.
Kg. The dosage varies depending on the symptoms and administration method, but in the case of oral administration, the usual daily dose per adult is 1 mg to 5000 mg, preferably 10 mg to 2000 mg, and in the case of injection, 1 mg to 5000 mg, preferably 10 mg to 1000 mg.
It can be administered once or in divided doses. The compounds can be administered to prevent cataract progression. In the experimental examples described below, the pharmacological effects of this compound will be demonstrated using domestic rabbits, and it is known that domestic rabbits are a reliable model for humans with regard to the pharmacological effects. Experimental Example 1 N-acetylcysteine was orally administered in advance to 1 group of 5 domestic rabbits weighing 2.5 to 3.0 kg at a concentration of 1.5 g/Kg (the amount of N-acetyl cysteine calculated per 1 kg of rabbit body weight). , naphthalene after 6 hours
Naphthalene suspended in polysorbate 80 at a concentration of 1.5 g/Kg was orally administered together with the control group, and 24 hours and 29.5 hours later, observation of vacuole formation in the lens (Table 1) and blood naphthalene concentration. (Table 2) and the amount of reduced glutathione in the crystalline lens (Table 3) were determined.

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Claims (1)

[Claims] 1 An anti-cataract agent consisting of or containing N-acetylcysteine.