The interrelationship between gasotransmitters and lead-induced renal toxicity in rats

Oxidized yeast glucan alleviates lead-induced toxicity in mice by improving intestinal health to inhibit Pb absorption and reducing kidney oxidative stress

This study investigated the protective effects and Pb-excretion mechanisms of yeast glucans (YG) with varying oxidation degrees in Pb-exposed mice. Results demonstrated that all three glucans effectively reduced blood lead levels, alleviated inflammation, and mitigated liver damage in Pb-exposed mice, with highly oxidized yeast glucan (OYG2) exhibiting the greatest efficacy. Furthermore, the glucans attenuated Pb-induced oxidative stress and pathological changes in the kidney by elevating glutathione and superoxide dismutase levels, thereby restoring renal excretory function (blood urea nitrogen and creatinine). This restoration contributed to maintaining electrolyte homeostasis (Na+, Cl-, K+) and significantly enhanced lead excretion efficiency via urine. Additionally, the glucans modulated intestinal microbiota balance, promoted short-chain fatty acid production, and repaired Pb-induced intestinal barrier damage by upregulating tight junction proteins (ZO-1, Occludin, Claudin-1). In conclusion, yeast glucans, particularly OYG2, effectively inhibited Pb absorption and facilitated its excretion through feces, highlighting their potential as a therapeutic strategy for lead toxicity.

Assessment of the effect of sodium tetraborate on oxidative stress, inflammation, and apoptosis in lead-induced nephrotoxicity

Exposure to Pb, a toxic heavy metal, is a risk factor for renal damage. Borax, an essential trace element in cellular metabolism, is a naturally occurring compound found in many foods. This study investigated the effects of sodium tetraborate (ST), a source of borax, on renal oxidative stress and inflammation in rats exposed to Pb. Wistar Albino rats (n = 24) were divided into four groups: Control (0.5 mL, i.p. isotonic), Pb (50 mg/kg/day/i.p.), ST (4.0 mg/kg/day/oral), and Pb + ST groups. At the end of the five-day experimental period, kidney tissue samples were obtained and analyzed. Histopathologically, the Pb-induced damage observed in the Pb group improved in the Pb + ST group. Immunohistochemically, Pb administration increased the expression of inducible nitric oxide synthase, cyclooxygenase-2, and caspase-3. When evaluated biochemically, Pb application inhibited catalase and glutathione peroxidase (GSH-Px) enzyme activities and activated superoxide dismutase enzyme activity. An increase in malondialdehyde levels was considered an indicator of damage. ST application increases glutathione peroxidase enzyme activity and decreased malondialdehyde levels. These results indicate that ST might play a protective role against Pb-induced renal damage via the upregulation of renal tissue antioxidants and cyclooxygenase-2, inducible nitric oxide synthase, and caspase-3 immunoexpression.

Abdelaziz M, Sakr HI, Ahmed OM. Bone marrow-derived mesenchymal stem cells reduce CCl4-induced kidney injury and fibrosis in male Wistar rats

AIM

This study explores the possible therapeutic role of rats and mice bone marrow-derived mesenchymal stem cells (BM-MSCs) on renal damage and toxicity brought on by carbon tetrachloride (CCl4) in Wistar rats.

METHODS

Following an intraperitoneal injection of CCl4 (0.5 mL/kg b.w. twice weekly) for eight weeks, male Wistar rats were intravenously treated with rats and mice BM-MSCs (1 × 106 cells in 0.2 mL Dulbecco's Modified Eagle Medium (DMEM)/rat/week) a week for four weeks. Kidney functions were evaluated and kidney samples were examined using hematoxylin and eosin (H&E), Masson's trichrome (MT) staining techniques, and electron microscopy analysis. Kidney cyclooxygenase-2 (COX-2), protein 53 (p53), and tumor necrosis factor-α (TNF-α) were detected by immunohistochemical staining techniques. Additionally, bioindicators of oxidative stress and antioxidant defense systems were identified in kidney tissue.

RESULTS

In CCl4-injected rats, serum creatinine, urea, and uric acid levels significantly increased, as did renal lipid peroxidation (LPO), while superoxide dismutase, glutathione peroxidase (GPx), glutathione (GSH) transferase, and GSH levels significantly dropped in the kidneys. Histologically, the kidneys displayed a wide range of structural abnormalities, such as glomerular shrinkage, tubular dilations, inflammatory leukocytic infiltration, fibroblast proliferation, and elevated collagen content. Inflammatory cytokines like COX-2 and TNF-α as well as the pro-apoptotic mediator p53 were considerably upregulated. Treatment of BM-MSCs from mice and rats with CCl4-injected rats considerably reduced the previously noted abnormalities.

CONCLUSIONS

By boosting antioxidant defense and reducing apoptosis and inflammation, BM-MSCs from mice and rats were able to enhance kidney function and histological integrity in rats that had received CCl4 injections.

The impact of PM2.5 on kidney

PM2.5 poses a severe risk to kidneys, inducing kidney function decline, increasing the risk of suffering from chronic kidney diseases and promoting the occurrence and development of various renal tumors. The mechanism of PM2.5-induced renal injury may involve oxidative stress, inflammatory response, and cytotoxicity. This paper elaborated PM2.5-induced kidney damage and the corresponding possible mechanism so as to raise awareness of air pollution and reduce the damage to human body.

Adansonia digitata L. fruit shell extract alleviates lead-induced neurotoxicity in mice via modulation of oxidative stress and a possible chelating activity

BACKGROUND

Lead is a ubiquitous environmental heavy metal known to induce neurotoxicity. It has been postulated that substance with high antioxidant capacity could alleviate lead-induced neurotoxicity. Adansonia digitata fruit shell extract (ADFS) has been reported to have high phenolic contents and exerts antioxidant activity. This study investigated the effects of Adansonia digitata fruit shell extract on lead-induced neurotoxicity in mice.

METHODS

Male balb/c mice (n = 7) were administered with Pb-acetate (50 mg/kg) 30 mins before ADFS (250 mg/kg and 500 mg/kg) or succimer (50 mg/kg) per orally for 28 days. Motor activities were evaluated on days 29 and 30 through horizontal bar and open field tests respectively. Further, spectrophotometry, atomic absorption spectrophotometry and haematoxylin and eosin staining were carried-out to determine the expression of oxidative stress biomarkers, level of lead concentration in the brain and histology of the cerebellum respectively.

RESULTS

Lead acetate exposure significantly (p < 0.05) induced motor deficits in horizontal bar test and open field test, caused oxidative stress, high concentration of lead in the brain as well as histological aberration in the cerebellum. ADFS significantly (p < 0.05) reversed the motor deficits evident by increased muscle strength and number of lines crossed. Further, ADFS significantly reversed oxidative stress evident by increased levels of SOD, CAT and GSH and decreased level of MDA. There was also significant (p < 0.05) decrease in brain lead concentration as well as reduced cerebellar cells death.

CONCLUSION

Findings suggest that ADFS attenuated motor deficits via inhibition of oxidative stress and chelating activity which is comparable to succimer. Hence, ADFS should be explored for possible development of chelating agent against lead and other heavy metals toxicity.

Battery wastewater induces nephrotoxicity via disordering the mitochondrial dynamics

The rapid development of new energy battery enterprises manifolds the obsolete and scrapped batteries which are considered serious concern for the environment and ecology. Increasing trend of recycling batteries waste is public hazard throughout the world. The batteries wastes affect the various body systems but exact toxicological mechanism of battery wastewater is still unexplored. The present study was designed to observe the toxicological effects of batteries wastes on kidney functional dynamics. In this experiment, a total of 20 male mice were randomly divided into two groups including control and treatment (battery wastewater) group. The control group was provided the normal saline while the battery wastewater group were provided battery waste-water for a period of 21 days. The isolated kidneys were processed for histopathological analysis, biochemical assays, mRNA and protein estimation. The results showed that battery wastewater provision increased the mitochondrial division-related genes and proteins (Drp1, MFF, Fis1) and decreased the expression level of fusion-related nuclear proteins (MFN1, MFN2, OPA1) in kidneys. Moreover, the battery wastewater exposure significantly up-regulated the autophagy (PINK, Parkin, mTOR, ATG5, LC3-b, p62) and apoptosis (Bax, Cytc, APAF1, P53, Caspase3, Caspase8) related mRNA and proteins levels in kidneys. However, down-regulation of mRNA and proteins levels of Bcl2 and Beclin1 were also observed in kidneys after batteries wastes exposure. In conclusion, it is evident that the battery wastewater leads to renal apoptosis and autophagy by disrupting the mitochondrial dynamics in mice kidneys.

Analysis of Threshold Effect of Urinary Heavy Metal Elements on the High Prevalence of Nephrolithiasis in Men

Exposure to heavy metals in the environment exerts serious effects on kidney health. However, the effects of joint exposure on the kidneys have been rarely studied, particularly in non-occupational exposure high-risk populations. This study provided a reference threshold range of heavy metals in urine and explored the effect of joint exposure on nephrolithiasis in men. The data were obtained from the China Multi-Ethnic Cohort database, and 1502 men were included in the study. A two-piece-wise regression model was used to assess the dose-response relationship between heavy metal exposure and nephrolithiasis. The least absolute shrinkage and selection operator regression model was used to calculate the score of joint exposure to heavy metals. The threshold effect analysis revealed a linear relationship between the concentration of arsenic (As) in the urine and the prevalence of nephrolithiasis, whereas a nonlinear relationship was observed with cadmium (Cd), chromium (Cr), mercury (Hg), and lead (Pb). In addition, As, Cd, Cr, Hg, and Pb may significantly affect the joint exposure effect. Moreover, the final risk of nephrolithiasis increased by 123% (P for trend < 0.001). This study found a threshold relationship between heavy metals (Cd, Cr, Hg, Pb) in male urine and the occurrence of nephrolithiasis. Joint exposure to heavy metals in urine caused a high-risk effect on nephrolithiasis. The study provided a reference threshold value of related studies and indicated that environmental pollution caused by heavy metals should be reduced.

Mechanism of preservation of the intestinal mucosa architecture and NF-κB/PGE2 reduction by hydrogen sulfide on cholera toxin-induced diarrhea in mice

AIMS

Investigate the involvement of Hydrogen sulfide (H₂S) in inflammatory parameters and intestinal morphology caused by cholera toxin (CT) in mice.

MAIN METHODS

Mice were subjected to the procedure of inducing diarrhea by CT in the isolated intestinal loop model. The intestinal loops were inoculated with H₂S donor molecules (NaHS and GYY 4137) or saline and CT. To study the role of EP2 and EP4 prostaglandin E2 (PGE2) receptors in the H₂S antisecretory effect, PAG (DL-propargylglycine - inhibitor of cystathionine-γ-lyase (CSE)), PF-04418948 (EP2 antagonist) and ONO-AE3-208 (EP4 antagonist) were used. The intestinal loops were evaluated for intestinal secretion, relation of the depth of villi and intestinal crypts, and real-time PCR for the mRNA of the CXCL2, IL-6, NOS-2, IL-17, NF-κB1, NF-κBIA, SLC6A4 and IFN-γ genes.

KEY FINDINGS

H₂S restored the villus/crypt depth ratio caused by CT. NaHS and GYY 4137 increased the expression of NF-κB1 and for the NF-κBIA gene, only GYY 4137 increased the expression of this gene. The increased expression of NF-κB inhibitors, NF-κB1 and NF-κBIA by H₂S indicates a possible decrease in NF-κB activity. The pretreatment with PAG reversed the protective effect of PF-04418948 and ONO-AE3-208, indicating that H₂S probably decreases PGE2 because in the presence of antagonists of this pathway, PAG promotes intestinal secretion.

SIGNIFICANCE

Our results point to a protective activity of H₂S against CT for promoting a protection of villus and crypt intestine morphology and also that its mechanism occurs at least in part due to decreasing the activity of NF-κB and PGE2.

Lead nitrate and cadmium chloride induced hepatotoxicity and nephrotoxicity: Protective effects of sesamol on biochemical indices and pathological changes

Lead nitrate (LN) and cadmium chloride (CdCl₂ ), regarded as environmental contaminants, are toxic heavy metals. Sesamol is a dietary phytochemical found in sesame oil. We aimed to analyze the hepatotoxic and nephrotoxic effects of LN and CdCl₂ and to evaluate the possible protective effect of sesamol. LN (90 mg/kg bw per day), CdCl₂ (3 mg/kg bw per day), and sesamol (50 mg/kg bw per day) were given to rats via gavage for 28 days. Total protein, albumin, alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, total cholesterol, urea, uric acid, creatinine, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, malondialdehyde, acetylcholinesterase, and histopathological changes were investigated in liver and kidney tissues. Lead and cadmium were found to result in decreases in the antioxidant enzymes and acetylcholinesterase activities, increases in malondialdehyde levels, and changes in serum biochemical parameters and various pathological findings. An improvement in all these parameters was observed in the sesamol-treated groups. PRACTICAL APPLICATIONS: Heavy metals are used in many areas of the industry all over the world. Heavy metals which include lead nitrate and cadmium chloride cause cell damage by oxidative stress. Some of the examining parameters for oxidative stress are SOD, GST, MDA, GPx, and CAT. However, some chemicals such as sesamol are well-liked and widely used as antioxidants against xenobiotic toxicity. We also indicate that sesamol has been shown to protective effect against heavy metals caused cell damage.

Metabolic profiling of 19 amino acids in triptolide-induced liver injured rats by gas chromatography-triple quadrupole mass spectrometry

The liver is an important organ for amino acid metabolism, and its damage can be reflected in the changes of amino acid level in the body. Triptolide (TP) has broad anti-inflammatory and anti-tumor activities, but its clinical application is limited due to hepatotoxicity. In this work, a simple, accurate and sensitive gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS/MS) method was developed and validated for evaluating the serum levels of amino acids from control and TP-induced liver injured rats, and chemometric analysis was employed for amino acid metabolic profiles analysis. It was found that 11 amino acids showed significant changes after TP administration, and they were mainly involved in 5 metabolic pathways that are phenylalanine, tyrosine and tryptophan biosynthesis, alanine, aspartate and glutamate metabolism, glutamine and glutamate metabolism, phenylalanine metabolism and arginine biosynthesis. Five amino acids including tyrosine, glutamine, glutamic acid, tryptophan and alanine were identified as biomarkers of TP hepatotoxicity by further analysis. These results indicated that the novel amino acid metabolic profiling study based on the GC-QqQ-MS/MS provided not only exact concentrations of serum amino acids, but also a prospective methodology for evaluation of chemically induced liver injury.

The potential relationship between gasotransmitters and oxidative stress, inflammation and apoptosis in lead-induced hepatotoxicity in rats

The interrelationship between gasotransmitters and oxidative stress, inflammation and apoptosis in lead-induced hepatotoxicity was investigated in this study. On prolonged exposure, lead was accumulated in liver tissue of rats and impaired liver function and structure as assessed by measurement of the serum hepatic function markers and by histopathological examination. The accumulated metal induced oxidative stress, inflammation and apoptosis in the liver. Also, it increased nitric oxide (NO) production and decreased hydrogen sulfide (H₂S) level and heme oxygenase (HO-1) concentration in liver tissue. Decreasing of NO production by L-N(G)-nitroarginine methyl ester (L-NAME) and increasing of H₂S level by sodium hydrosulfide (NaHS) and carbon monoxide (CO) level by carbon monoxide-releasing molecule-A₁ (CORM-A₁) inhibited lead-induced impairment of liver function and structure. Concomitantly, these agents inhibited lead intoxication-induced oxidative stress, inflammation, apoptosis, nitrosative stress and reduction of HO-1 concentration and H₂S level. Furthermore, concurrent treatment with these agents inhibited lead intoxication-induced increase in the protein expressions of inducible NO synthase, tumor necrosis factor-alpha, interleukin-1beta and caspase-3 as well as decrease in protein expressions of HO-1 and cystathionine-γ-lyase in the liver. NO donor, l-arginine and H₂S and CO biosynthesis inhibitors, trifluoro-DL-alanine and zinc deutroporphyrin, respectively aggravated the toxic effects of lead. These results indicate, for the first time, that there is an interrelationship between gasotransmitters and lead-induced hepatotoxicity. The ability of L-N AME, NaHS and CORM-A₁ to provide protective effects against lead-induced hepatotoxicity may positively correlate, to their ability to suppress hepatic oxidative stress, nitrosative stress, inflammation and apoptosis.

Ameliorative Effect of Selenomethionine on Cadmium-Induced Hepatocyte Apoptosis via Regulating PI3K/AKT Pathway in Chickens

Selenium (Se) is a trace element for human and animal health. Cadmium (Cd) is a known human carcinogen. The effects of Cd on the environment and humans are well known. Because chickens are at the top of the food chain, it is a good experimental animal model for assessing heavy metal toxicity and its potential threat to humans. Selenomethionine (Se-met) is a suitable form for nutritional Se supplementation. Therefore, the toxicity of Cd to the chicken liver and the antagonistic effects of Se-met on Cd were examined at the molecular level in the present study. The results showed that oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and heat shock proteins (HSPs)-related genes) in the Cd group have changed significantly, indicating Cd induced hepatocyte stress and apoptosis. Interestingly, the changes in oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and HSPs-related genes) in the Cd-Se-met group were mitigated compared with the control group. Our results indicated that Cd can induce hepatocyte apoptosis and stress in the chickens. Se-met has an ameliorative effect on Cd-induced apoptosis of chicken hepatocyte by regulating PI3K/AKT pathway. Our findings will provide a new insight for better understanding of the detoxification function of Se-met to heavy metals.

Ameliorative effect of curcumin on lead-induced hematological and hepatorenal toxicity in a rat model

INTRODUCTION

Lead (Pb) is a ubiquitous toxic heavy metal that inflicts numerous clinical consequences on humans. Curcumin is the principal component of turmeric, which is reported to have antioxidative properties. This study aimed at evaluating the ameliorative effects of curcumin on Pb-induced hepatorenal toxicity in a rat model.

METHODS

Thirty-six male Sprague-Dawley rats were randomly assigned into five groups with 12 rats in the control (normal saline) and six rats each for the lead-treated group (LTG) (50 mg/kg lead acetate [Pb acetate] for 4 weeks), recovery group (50 mg/kg Pb acetate for 4 weeks and left with no treatment for another 4 weeks), treatment group 1 (Cur100) (50 mg/kg Pb acetate for 4 weeks, followed by 100 mg/kg curcumin for 4 weeks), and treatment group 2 (Cur200) (50 mg/kg Pb acetate for 4 weeks, followed by 200 mg/kg curcumin for 4 weeks). All the experimental groups received oral treatments via orogastric-tube on alternate days. Pb concentration in the liver and kidney of the rats were evaluated using inductive-coupled plasma mass spectrometry techniques.

RESULTS

Pb-administered rats revealed significant alteration in oxidative status and increased Pb concentration in their liver and kidney with obvious reduction of hemogram and increased in leukogram as well as aberration in histological architecture of the liver and kidney. However, treatment with curcumin reduces the tissue Pb concentrations and ameliorates the above mention alterations.

CONCLUSIONS

The results in this study suggested that curcumin attenuates Pb-induced hepatorenal toxicity via chelating activity and inhibition of oxidative stress.

Hydrogen sulfide renal protective effects: possible link between hydrogen sulfide and endogenous carbon monoxide in a rat model of renal injury

Hydrogen sulfide (H2S), along with nitric oxide (NO) and carbon monoxide (CO), proved to have renoprotective effects in various renal diseases. Therefore, this study investigated the renoprotective effect of H2S, in a renal injury model, and its crosstalk with other gasotransmitters such as CO. Thirty-two adult rats were divided into four groups: control, gentamicin (GEN)-treated, GEN + sodium hydrosulfide (NaHS), and GEN + NaHS + zinc protoporphyrin (ZnPP) groups. GEN was used to induce renal injury, NaHS is a water-soluble H2S, and ZnPP is a selective heme oxygenase-1 (HO-1) inhibitor used to inhibit CO synthesis in vivo. NaHS improved kidney functions in the GEN group as evidenced by significantly lower levels of renal injury markers: serum urea, creatinine, uric acid, urinary albumin excretion, and urinary albumin/creatinine. Moreover, NaHS administration to the GEN-treated group significantly lowered renal levels of NO and tumor necrosis factor-α with an increase in total antioxidant, HO-1, and interleukin-10 levels. Furthermore, NaHS administration downregulated the GEN-induced overexpression of the renal inducible nitric oxide synthase (iNOS) and upregulated the suppression of endothelial nitric oxide synthase (eNOS) with improvement in the histological examination and periodic acid Schiff (PAS) staining. However, this improvement in kidney function produced by NaHS was reduced by combination with ZnPP but still improved as compared with the GEN-treated group. The renoprotective effects of H2S can be through its effects on renal tissue antioxidants, pro-inflammatory and anti-inflammatory cytokines, and expression of eNOS and iNOS which can be partially dependent on CO pathway via induction of HO-1 enzyme.

Carbon monoxide: An emerging therapy for acute kidney injury

Treating acute kidney injury (AKI) represents an important unmet medical need both in terms of the seriousness of this medical problem and the number of patients. There is also a large untapped market opportunity in treating AKI. Over the years, there has been much effort in search of therapeutics with minimal success. However, over the same time period, new understanding of the underlying pathobiology and molecular mechanisms of kidney injury have undoubtedly helped the search for new therapeutics. Along this line, carbon monoxide (CO) has emerged as a promising therapeutic agent because of its demonstrated cytoprotective, and immunomodulatory effects. CO has also been shown to sensitize cancer, but not normal cells, to chemotherapy. This is particularly important in treating cisplatin-induced AKI, a common clinical problem that develops in patients receiving cisplatin therapies for a number of different solid organ malignancies. This review will examine and make the case that CO be developed into a therapeutic agent against AKI.

Curcumin Attenuates Lead-Induced Cerebellar Toxicity in Rats via Chelating Activity and Inhibition of Oxidative Stress

Lead (Pb) is a toxic, environmental heavy metal that induces serious clinical defects in all organs, with the nervous system being its primary target. Curcumin is the main active constituent of turmeric rhizome (Curcuma longa) with strong antioxidant and anti-inflammatory properties. This study is aimed at evaluating the therapeutic potentials of curcumin on Pb-induced neurotoxicity. Thirty-six male Sprague Dawley rats were randomly assigned into five groups with 12 rats in the control (normal saline) and 6 rats in each of groups, i.e., the lead-treated group (LTG) (50 mg/kg lead acetate for four weeks), recovery group (RC) (50 mg/kg lead acetate for four weeks), treatment group 1 (Cur100) (50 mg/kg lead acetate for four weeks, followed by 100 mg/kg curcumin for four weeks) and treatment group 2 (Cur200) (50 mg/kg lead acetate for four weeks, followed by 200 mg/kg curcumin for four weeks). All experimental groups received oral treatment via orogastric tube on alternate days. Motor function was assessed using a horizontal bar method. The cerebellar concentration of Pb was evaluated using ICP-MS technique. Pb-administered rats showed a significant decrease in motor scores and Superoxide Dismutase (SOD) activity with increased Malondialdehyde (MDA) levels. In addition, a marked increase in cerebellar Pb concentration and alterations in the histological architecture of the cerebellar cortex layers were recorded. However, treatment with curcumin improved the motor score, reduced Pb concentration in the cerebellum, and ameliorated the markers of oxidative stress, as well as restored the histological architecture of the cerebellum. The results of this study suggest that curcumin attenuates Pb-induced neurotoxicity via inhibition of oxidative stress and chelating activity.