Fish, a widely claimed healthy food for humans, could also pose problems to health due to (1) accumulation of pollutants, especially heavy metals, (2) presence of marine toxins such as tetrodotoxin, ciguatoxin or okadaic acid and (3) metabolic production of large amount of uric acid which may crystallize in kidney or in articulations. As tuna fish represents a large part of the traditional food in some countries, the possible impact of its consumption on public health was investigated, with special attention to biochemical and histological alterations related to the genital function. For that purpose, white or red muscle from tuna fish was added for 60 days to the diet of male rats, and attention was paid to biochemical and histological alterations related to the genital function. Feeding rats with white muscle, and much more markedly with red muscle known to be more metabolically active, resulted in (1) an elevated uric acid level in blood, (2) an increase in lead level in testis, (3) an atrophy of the genital tract, including testes, epididymis, prostate and seminal vesicles, (4) a lowering of plasma testosterone level, (5) a decrease in spermatozoids number and motility, (6) an oxidative stress in testes including an increase in lipids peroxidation level and enhanced superoxide-dismutase, catalase and glutathione-peroxidase activities. We conclude that consumption of tuna fish meat, especially the dark one, should be reduced.

The aim of the present study was to determine whether administration of Juniperus phoenicea extract would have any advantage over allopurinol therapy on (1) lipids peroxidation level and (2) antioxidant activity in liver, erythrocyte and testis of hyperuricemic rats by oxonate administration. In hyperuricemic rats, levels of lipids peroxidation in liver, erythrocyte and testis were found to be significantly increased as compared to control rats (p < 0.05). Activities of glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) were also significantly increased as compared to the controls (p < 0.05). An ameliorative effect was obtained in hyperuricemic rats by oral treatment with either allopurinol (10 mg/kg body weight (bw)) or J. phoenicea extract (100 or 200 mg/kg bw). The 100 mg/kg dose revealed to be efficient in reducing uric acid level in blood and the 200 mg/kg dose strongly reduced the activities of SOD, CAT and GPX in liver and erythrocyte. Our results support that the consumption of J. phoenicea extract should be recommended in ethnomedicinal practice to reduce the risk of gout by decreasing the uric acid level in blood and to confer some protection against oxidative stresses at organs level.

In recent years, a number of studies have clearly pointed out the nutritional benefits of fish consumption. However, some concerns about potential health risks derived from contaminants found in fish have also been raised. Therefore, balancing adequately the risks and benefits of fish consumption is currently a health key issue. As tuna fish represents a large part of the traditional food in some countries, the possible impact of tuna fish consumption on public health was investigated. Hepatic damages following consumption of tuna fish white (ordinary) or red (dark) muscle were evaluated in rat. Under our experimental conditions, feeding the animals for 60 days with white or, more markedly, red tuna meat resulted in 1) an elevated uric acid level in blood, 2) an accumulation of lead in liver, 3) an atrophy of liver, 4) an increase in plasma aspartate aminotransferase and alanine aminotransferase activities, and 5) an oxidative stress in liver including an increased level of lipids peroxidation and enhanced activities of superoxide dismutase, catalase and glutathione peroxidase. In addition, liver histology revealed several abnormalities. These alterations could be attributed to both lead accumulation and high purine levels in tuna meat. We conclude that attention should be paid to a possible health impact of frequent and important consumption of tuna fish meat, especially the dark one.