Protective efficacy of rutin against acrylamide-induced oxidative stress, biochemical alterations and histopathological lesions in rats

Environmental toxicants and nephrotoxicity: Implications on mechanisms and therapeutic strategies

Kidneys are one of the most important organs in the human body. In addition to filtering 200 liters of fluid every 24 hours, the kidney also regulates acid-base balance, maintains electrolyte balance, and removes waste and toxicants from the body. Nephrotoxicity is the term used to describe the deterioration of kidney function caused by the harmful effects of medications and various types of environmental toxicants. Exposure to environmental toxicants is an inevitable side effect in the world's increasing industrialization and even more prevalent in underdeveloped nations. Growing data over the past few years has illuminated the probable connection between environmental toxicants and nephrotoxicity. Phthalates, microplastics, acrylamide and bisphenol A are environmental toxicants of particular concern, which are known to have nephrotoxic effects. Such toxicants may accumulate in the kidneys of humans after being consumed, inhaled, or come into contact with the skin. They can enter cells through endocytosis and accumulate in the cytoplasm. Small-sized nephrotoxicants can cause a variety of ailments including inflammation with increased production of pro-inflammatory cytokines, oxidative stress, mitochondrial dysfunction, autophagy, and apoptosis. This study uncovers the potential for new insights concerning the relationship between various environmental toxicants and kidney health. The objectives of this review is to establish information gaps, assess and identify the toxicity mechanisms of different nephrotoxicants, identify innovative pharmacological therapies that demonstrate promising therapeutic benefits/ relevance, and discuss the predictions for the future based on the analysis of the literature.

Therapeutic role of boron on acrylamide-induced nephrotoxicity, cardiotoxicity, neurotoxicity, and testicular toxicity in rats: Effects on Nrf2/Keap-1 signaling pathway and oxidative stress

BACKGROUND

Acrylamide (ACR) is a heat-related carcinogen used in cooking some foods as well as in other thermal treatments. The present study aims to investigate the possible protective effect of boron (BA) against ACR-induced toxicity of kidney, brain, heart, testis, and bladder tissues in rats.

METHODS

Rats have been divided into 5 equal groups: Control (saline), ACR (38.27 mg/kg), BA (20 mg/kg), BA+ ACR (10 mg/kg + ACR), and BA+ ACR (20 mg/kg BA+ACR). Kidney tissue from rats was collected and the levels of malondialdehyde (MDA), glutathione (GSH), and the activity of superoxide dismutase (SOD) were measured. In addition, the kidneys of these animals, as well as the brain, heart, testes, and bladder tissues were examined for possible histological changes. Total Nrf2 and Keap-1 protein expression in kidney, heart, and testis tissues was examined by immunohistochemistry.

RESULTS

While significant increases in MDA levels were observed in the kidneys of rats receiving ACR alone, significant decreases in antioxidant markers (SOD and GSH) were observed. Besides, kidney, brain, heart, and testicular tissues were analyzed and damage was observed in the groups receiving ACR. However, no significant histologic changes were noted in the bladder tissue. Both dosages of BA in combination with ACR improved the changes in ACR-induced antioxidant tissue parameters. Despite the fact that MDA levels were decreased with these two dosages, histological structural abnormalities were found to be greatly improved.

CONCLUSION

Our results show that BA has a strong protective effect on ACR-induced multi-organ toxicity. The study results show that BA could be a potential element to reduce ACR toxicity to which we are often exposed.

Rutin and Hesperidin Revoke the Hepatotoxicity Induced by Paclitaxel in Male Wistar Rats via Their Antioxidant, Anti-Inflammatory, and Antiapoptotic Activities

Paclitaxel, one of the most effective chemotherapeutic drugs, is used to treat various cancers but it is exceedingly toxic when used long-term and can harm the liver. This study aimed to see if rutin, hesperidin, and their combination could protect male Wistar rats against paclitaxel (Taxol)-induced hepatotoxicity. Adult male Wistar rats were subdivided into 5 groups (each of six rats). The normal group was orally given the equivalent volume of vehicles for 6 weeks. The paclitaxel-administered control group received intraperitoneal injection of paclitaxel at a dose of 2 mg/Kg body weight twice a week for 6 weeks. Treated paclitaxel-administered groups were given paclitaxel similar to the paclitaxel-administered control group together with oral supplementation of rutin, hesperidin, and their combination at a dose of 10 mg/Kg body weight every other day for 6 weeks. The treatment of paclitaxel-administered rats with rutin and hesperidin significantly reduced paclitaxel-induced increases in serum alanine transaminase, aspartate transaminase, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transferase activities as well as total bilirubin level and liver lipid peroxidation. However, the levels of serum albumin, liver glutathione content, and the activities of liver superoxide dismutase and glutathione peroxidase increased. Furthermore, paclitaxel-induced harmful hepatic histological changes (central vein and portal area blood vessel congestion, fatty changes, and moderate necrotic changes with focal nuclear pyknosis, focal mononuclear infiltration, and Kupffer cell proliferation) were remarkably enhanced by rutin and hesperidin treatments. Moreover, the elevated hepatic proapoptotic mediator (caspase-3) and pro-inflammatory cytokine (tumor necrosis factor-α) expressions were decreased by the three treatments in paclitaxel-administered rats. The cotreatment with rutin and hesperidin was the most effective in restoring the majority of liver function and histological integrity. Therefore, rutin, hesperidin, and their combination may exert hepatic protective effects in paclitaxel-administered rats by improving antioxidant defenses and inhibiting inflammation and apoptosis.

Therapeutic role of melatonin on acrylamide-induced hepatotoxicity in pinealectomized rats: Effects on oxidative stress, NF-κB signaling pathway, and hepatocellular proliferation

Acrylamide (AA) is formed in some foods by the cooking process at high temperatures, and it could be a carcinogen in humans and rodents. The purpose of the current study was to reveal the possible protective effects of melatonin against AA-induced hepatic oxidative stress, hepatic inflammation, and hepatocellular proliferation in pinealectomized rats. Hence, the sham and pinealectomized rats were consecutively given AA alone (25 mg/kg) or with melatonin (10 mg/kg) for 21 days. Melatonin acts as an antioxidant, anti-inflammatory, and antiapoptotic agent and introduces as a therapeutic strategy for AA-induced hepatotoxicity. Melatonin supplementation reduced AA-caused liver damage by decreasing the serum AST, ALT, and ALP levels. Melatonin raised the activities of SOD and CAT and levels of GSH and suppressed hepatic inflammation (TNF-α) and hepatic oxidative stress in liver tissues. Moreover, histopathological alterations and the disturbances in immunohistochemical expression of NF-κB and Ki67 were improved after melatonin treatment in AA-induced hepatotoxicity. Overall, our results demonstrate that melatonin supplementation exhibits adequate hepatoprotective effects against hepatotoxicity of AA on pinealectomized rat liver architecture and the tissue function through the equilibration of oxidant/antioxidant status, the regulation of cell proliferation and the suppression of the release of proinflammatory cytokines.

Rutin and Hesperidin Alleviate Paclitaxel-Induced Nephrocardiotoxicity in Wistar Rats via Suppressing the Oxidative Stress and Enhancing the Antioxidant Defense Mechanisms

Paclitaxel is a primary chemotherapy agent that displays antitumor activity against a variety of solid tumors. However, the clinical effectiveness of the drug is hampered by its nephrotoxic and cardiotoxic side effects. Thus, this investigation aimed at assessing the protective effects of rutin, hesperidin, and their combination to alleviate nephrotoxicity caused by paclitaxel (Taxol), cardiotoxicity in male Wistar rats, as well as oxidative stress. Rutin (10 mg/kg body weight), hesperidin (10 mg/kg body weight), and their mixture were given orally every other day for six weeks. Rats received intraperitoneal injections of paclitaxel twice weekly, on the second and fifth days of the week, at a dose of 2 mg/kg body weight. In paclitaxel-treated rats, the treatment of rutin and hesperidin decreased the elevated serum levels of creatinine, urea, and uric acid, indicating a recovery of kidney functions. The cardiac dysfunction in paclitaxel-treated rats that got rutin and hesperidin treatment also diminished, as shown by a substantial reduction in elevated CK-MB and LDH activity. Following paclitaxel administration, the severity of the kidney and the heart's histopathological findings and lesion scores were markedly decreased by rutin and hesperidin administration. Moreover, these treatments significantly reduced renal and cardiac lipid peroxidation while markedly increased GSH content and SOD and GPx activities. Thus, paclitaxel likely induces toxicity in the kidney and the heart by producing oxidative stress. The treatments likely countered renal and cardiac dysfunction and histopathological changes by suppressing oxidative stress and augmenting the antioxidant defenses. Rutin and hesperidin combination was most efficacious in rescuing renal and cardiac function as well as histological integrity in paclitaxel-administered rats.

The role of Bax/Bcl-2 and Nrf2-Keap-1 signaling pathways in mediating the protective effect of boric acid on acrylamide-induced acute liver injury in rats

INTRODUCTION

This study aims to investigate whether boric acid (BA) can protect rats from acrylamide (AA)-induced acute liver injury.

MATERIALS AND METHODS

AA was used to induce acute liver injury. Thirty rats were divided into five group including Group 1 (saline), Group 2 (AA), Group 3 (20 mg/kg BA), Group 4 (10 mg/kg BA+AA) and Group 5 (20 mg/kg BA+AA). Their blood and liver were harvested to be kept for analysis. Liver function enzyme activities were performed by spectrophotometric method. Catalase (CAT), superoxide dismutase (SOD) activity, and malondialdehyde levels were determined by colorimetric method. The in-silico studies were performed using the "blind docking" method.

RESULTS

Administration AA to rats, biochemical parameters, liver histology, and expression levels of apoptotic markers were negatively affected. However, after the administration of BA, the altered biochemical parameters, liver histology, and expression levels of apoptotic markers were reversed. Moreover, the mechanisms of AA-induced deterioration in the levels of SOD, CAT, and Nrf2-Keap-1 and the mechanisms of the protective effect of BA against these deteriorations were explained by in silico studies.

CONCLUSION

Thus, the present study could explain the interactions between AA and thiol-containing amino acid residues of Keap-1, the effect of BA on these interactions, and the biochemical toxicity caused by the AA. In this sense, this work is the first of its kind in the literature. Based on the biochemical, histopathological, and in silico results, it can be suggested that BA has the potential to be used as a protective agent against AA-induced liver injury.

Acrylamide and Potential Risk of Diabetes Mellitus: Effects on Human Population, Glucose Metabolism and Beta-Cell Toxicity

Diabetes mellitus is a frequent endocrine disorder characterized by hyperglycemia. Acrylamide (AA) is food contaminant formed during the high-temperature processing of food rich in carbohydrates and low in proteins. Recent human epidemiological studies have shown a potential association between AA exposure and the prevalence of diabetes in the general population. In male rats, AA treatment promoted pancreatic islet remodeling, which was determined by alpha-cell expansion and beta-cell reduction, while in female rats AA caused hyperglycemia and histopathological changes in pancreatic islets. In vitro and in vivo rodent model systems have revealed that AA induces oxidative stress in beta cells and that AA impairs glucose metabolism and the insulin signaling pathway. Animal studies have shown that diabetic rodents are more sensitive to acrylamide and that AA aggravates the diabetic state. In this review, we provide an overview of human epidemiological studies that examined the relation between AA exposure and glucose disorders. In addition, the effects of AA treatment on pancreatic islet structure, beta-cell function and glucose metabolism in animal models are comprehensively analyzed with an emphasis on sex-related responses. Furthermore, oxidative stress as a putative mechanism of AA-induced toxicity in beta cells is explored. Finally, we discuss the effects of AA on diabetics in a rodent model system.