Effect of cylindrospermopsin on the hepatotoxicity in wistar rats

Abstract

A naturally-derived cyanotoxin, cylindrospermopsin (CYN), present in freshwater systems, poses a threat to human health due to potential hepatotoxicity. The present study aimed to determine the hepatotoxic effects of CYN on male Wistar rats. Following ethical clearance, 35 rats were divided into five groups. Test groups were administered with pre-prepared solutions to provide three doses of CYN: 0.175 µg/kg, 0.140 µg/kg, and 0.105 µg/kg. Well-water collected from Padaviya (0.161 µg/kg of CYN) was given to the environmental-exposure group (EN) and distilled water was administered to the control. The total duration of exposure was 90 days. Blood samples were collected at 0, 7, 14, 28, 42, 60, 90 days. Aspartate amino-transferase (AST), aspartate alaninetransferase (ALT), and full blood count (FBC) were analyzed. At 90 days, hepatic tissue samples were taken for histology. The mean body weight of the treated and control groups of rats gradually increased until the 90 th day. A statistically significant reduction (p < 0.05) in increment of body weights was observed in CYN-treated rats, compared to the control, at 12 th and 13 th weeks. Relative weights of the livers of treated groups were significantly lower (p < 0.05) than those of the control group. The highest AST and ALT concentrations were recorded in rats given a CYN dose of 0.175 µg/kg. Haematology revealed a significant (p < 0.05) reduction in monocyte and lymphocyte counts in the EN group given well-water compared to the control. Ballooning degeneration, Kupffer cell hyperplasia, lobular haemorrhage and necrosis, perivenular inflammation, and sinusoidal congestion were observed in the livers of treated groups. The findings show that prolonged exposure to CYN contaminated water leads to hepatotoxicity in Wistar rats.

Biodegradation of the cyanotoxin cylindrospermopsin by Bacillus cereus, Micrococcus luteus and Alcaligenes faecalis&nbsp;

“…During the study of Abeysiri et al (2018b), a positive correlation (p < 0.05) between the CYN-producing cyanobacterial cell density and the CYN concentrations was observed in the surface and groundwater sources of CKDu (chronic kidney disease of unknown aetiology) strike areas in Sri Lanka. Additionally, Abeysiri et al (2018a) recorded the presence of CYN in well water samples of CKDu endemic areas in the Anuradhapura district.…”

“…Certain studies suggest that CYN has a bioaccumulation factor (BAF) of 4-171, indicating the potential to bioaccumulate in aquatic species (Scarlett et al, 2020). During chronic toxicity, it acts as a hepatotoxin, resulting in severe liver necrosis (Abeysiri et al, 2021b). Further, it affects kidneys (Abeysiri et al, 2021c) and has the potential to cause cytotoxicity (Poniedziałek et al, 2014;Abeysiri et al, 2021a;Chichova et al, 2021).…”

“…During chronic toxicity, it acts as a hepatotoxin, resulting in severe liver necrosis (Abeysiri et al, 2021b). Further, it affects kidneys (Abeysiri et al, 2021c) and has the potential to cause cytotoxicity (Poniedziałek et al, 2014;Abeysiri et al, 2021a;Chichova et al, 2021). It has been reported that CYN has the potential to inhibit the synthesis of proteins such as globin and antioxidants such as glutathione, leading to oxidative stress (López-Alonso et al, 2013).…”