Does human ochratoxin A aggravate proteinuria in patients with chronic renal disease?

Ochratoxin A-Induced Nephrotoxicity: Up-to-Date Evidence

Ochratoxin A (OTA) is a mycotoxin widely found in various foods and feeds that have a deleterious effect on humans and animals. It has been shown that OTA causes multiorgan toxicity, and the kidney is the main target of OTA among them. This present article aims to review recent and latest intracellular molecular interactions and signaling pathways of OTA-induced nephrotoxicity. Pyroptosis, lipotoxicity, organic anionic membrane transporter, autophagy, the ubiquitin-proteasome system, and histone acetyltransferase have been involved in the renal toxicity caused by OTA. Meanwhile, the literature reviewed the alternative or method against OTA toxicity by reducing ROS production, oxidative stress, activating the Nrf2 pathway, through using nanoparticles, a natural flavonoid, and metal supplement. The present review discloses the molecular mechanism of OTA-induced nephrotoxicity, providing opinions and strategies against OTA toxicity.

The need to revisit ochratoxin A risk in light of diabetes, obesity, and chronic kidney disease prevalence

Ochratoxin A (OTA) is a mycotoxin, or fungal toxin, that contaminates multiple foodstuffs worldwide. Affected commodities include oats, wheat, maize, barley, raisins and other dried vine fruits, wine, beer, coffee, and cocoa. Although OTA has been shown to cause kidney disease, including kidney cancer, in multiple animal species, the impact of dietary OTA on human health from a global perspective has been less clear. Several epidemiological studies suggest an association between OTA exposure and human kidney disease, but evidence of causality has been limited. Nonetheless, because OTA is common in so many foodstuffs and may play a role in kidney disease, we consider it important to improve the body of evidence surrounding OTA's adverse effects to humans, as well as human dietary exposures in different parts of the world. This is especially true in the light of increasing type 2 diabetes and obesity prevalence worldwide; both conditions frequently lead to chronic kidney disease (CKD), and may synergize with dietary OTA exposure to increase CKD risk.

Phenolic acid protects of renal damage induced by ochratoxin A in a 28-days-oral treatment in rats

The present study aimed to characterize the chlorogenic acid (ChlA) capacity to reverse the toxic effects induced by ochratoxin A (OTA) in a subacute toxicity test in rats. Male Wistar rats were fed orally by gavage for 28 days with OTA (0.4mg/kg bw/day), ChlA (5mg/kg bw/day) or the combination OTA (0.4mg/kg bw/day)+ChlA (5mg/kg bw/day). No deaths, no decrease in feed intake or body weight in any experimental group were recorded. The negative control group and the animals treated with ChlA alone showed no changes in any parameters evaluated. In OTA-treated group significant changes such as decrease in urine volume, proteinuria, occult blood, increase in serum creatinine values; decrease in absolute and relative kidney weight and characteristics histopathological lesions that indicated kidney damage were observed. However, limited effect on oxidative stress parameters were detected in kidneys of OTA-treated group. Animals treated with the combination OTA+ChlA were showed as negative control group in the evaluation of several parameters of toxicity. In conclusion, ChlA, at given concentration, improved biochemical parameters altered in urine and serum and pathological damages in kidneys induced by OTA exposure, showing a good protective activity, but not by an apparent antioxidant mechanism.

Retrospective Study of Melamine/Cyanuric Acid-Induced Renal Failure in Dogs in Korea between 2003 and 2004

In early 2007, American pet food ingredients leading to nephrotoxic renal failure of dogs and cats raised serious concerns about the safety of pet foods. Major pet food companies recalled more than 1,000 commercial pet foods in consideration of pet safety. A similar pet food-associated outbreak of nephrotoxic renal failure occurred in Asia, in late 2003 and 2004, resulting in a similar extensive pet food recall. At that time, contamination of ingredients with a nephrotoxin-producing fungus at a pet food production facility was suspected. However, toxicologic evidence to substantiate a mycotoxicosis was lacking. Moreover, the renal lesions were not typical of those reported with fungal nephrotoxins. During 2003 and 2004, 14 dogs were presented to the Veterinary Medical Teaching Hospital of Konkuk University, Seoul, Korea, with renal failure and distinctive renal pathologic findings. Grossly, the kidneys were greenish in color with greenish uroliths in the renal pelvis or bladder. Histologically, characteristic crystals with pinwheel radiating striations were present in distal tubular segments. Toxicologic analysis identified melamine, cyanuric acid, and ammelide in deparaffinized formalin-fixed kidney samples.

Ochratoxins: a global perspective

Ochratoxins have been overshadowed by better-known mycotoxins, but they are gaining importance. Here we consider ochratoxins in the context of aflatoxins, which are better understood than ochratoxins on many levels. We review recent work on taxonomic distribution, contamination of commodities, biosynthesis, toxicity and regulatory aspects of ochratoxins. We focus on ochratoxins in coffee, since coffee is becoming a key commodity in ochratoxin research and regulation.

Study of ochratoxin A as an environmental risk that causes renal injury in breast-fed Egyptian infants

Ochratoxin A (OTA) constitutes a real human threat. Its presence in human milk has previously been reported in different countries. This study is the first Egyptian report on the presence of OTA in both mothers' milk and infants' sera, addressing its correlation with infants' kidney functions, which was not previously addressed in the literature. Fifty healthy breast-lactating mothers and their infants who were exclusively breast-fed for at least 4 months were included. All of them were subjected to a thorough laboratory evaluation including determination of OTA concentration by high-performance liquid chromatography. Thirty-six mothers (72%) and their infants had been contaminated with OTA. Univariate analysis showed that the presence of OTA was associated with significantly higher levels of urinary beta2 microglobulin and microalbuminuria. Multivariate logistic regression analysis showed that there was a significant correlation between a higher OTA level in infants' sera and the degree of microalbuminuria. Mothers and their infants in our locality are exposed to a high OTA contamination rate (72%). To establish the role of OTA in causation of future renal dysfunction for infants, large controlled studies are warranted.