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Abstract

Mycotoxic nephropathy was induced in 18 young pigs by diets contaminated with strains of Aspergillus ochraceus containing ochratoxin A (OTA) and penicillic acid (PA) at levels corresponding to those naturally encountered in animal feeds in Bulgaria. Haematological and biochemical parameters, as well as the morphological and ultrastructural changes in various internal organs, and especially in the kidneys, were examined at different stages of development of the disease. A mottled surface of the kidneys was only seen in pigs exposed to a mouldy diet containing 180 ppb OTA for 3 months, but microscopic lesions, as well as changes in various haematological and biochemical parameters, were observed in all groups exposed to the same mouldy diet containing only 90 or 180 ppb OTA. Histological examination showed two types of change: degenerative changes affecting the epithelial cells of the proximal tubules, which predominated at the initial stage, and proliferative changes in the interstitium, which predominated at the later stage of the disease. Telangiectasis and lymph stasis were also seen, as well as degenerative changes in the capillary endothelium. The characteristic renal lesions were similar to those observed in spontaneous cases of mycotoxic porcine nephropathy in Bulgaria, but they were a little different from the classic Danish porcine nephropathy. The enhanced toxicity of OTA in our study may be due to a synergistic effect between OTA and PA or to some other unknown metabolites produced by the same ochratoxinogenic strains of A. ochraceus.

Diabetogenic Effects of Ochratoxin A in Female Rats

“…Changes in blood glucose levels as a result of OTA exposure have been reported in pigs [28,29,30,31], rabbits [32] and rats [27,33]. Studies with pigs on blood glucose levels following OTA toxication are contradictory [28,29,30,31].…”

“…Studies with pigs on blood glucose levels following OTA toxication are contradictory [28,29,30,31]. Decreased blood glucose levels were observed in rabbits fed with 1 and 2 ppm OTA-contaminated food after three weeks and, at week 8, blood glucose levels were half those of the control group [32].…”

Deleterious Effects of Mycotoxin Combinations Involving Ochratoxin A

“…This theory was supported by several studies: (1) Both OTA and PA were detected in feed in Bulgaria where nephropathy occurs and PA was present in two to three times higher concentrations than OTA; (2) Besides OTA and PA, feed was also contaminated with high levels of FB 1 and penitrem A, and low levels of CIT, DON, and ZEA. Contamination with PA and FB 1 was above 88%, suggesting that both PA and FB 1 might contribute to nephrotoxicity [12]; (3) Experimentally induced nephropathy in pigs and chickens fed with OTA and PA in concentrations that were naturally present in Bulgarian feed samples revealed similar degenerative changes in the kidneys as was seen in spontaneous cases of nephropathy [18,102]; (4) When simultaneously treated with these toxins, synergistic interactions between OTA and PA were recorded in pigs and chicks [103,104,105]. Taking into account the carcinogenic activity of PA reported by Dickens and Jones [92] and proven OTA carcinogenic properties, this combination might have higher carcinogenic potential than single toxins.…”

Development and Characterization of a Monoclonal Antibody against Ochratoxin B and Its Application in ELISA

“…Indeed, the biotransformation and elimination of OTB appeared more extensive than OTA in rats [10]. Moreover, although OTA is considered to be the major causative factor in Mycotoxic Porcine Nephropathy (MPN) in many European countries [14,15], the role of OTA in a similar human disease (BEN, Balkan Endemic Nephropathy) and in the observed increased incidence of human renal urothelial tumors is still under debate [16,17,18]. The potential role of OTB in both the human and the porcine nephropathy and the human urothelial tumors, has so far largely been ignored and remains to be elucidated.…”