Protective effects of Allium hirtifolium Boiss extract on cadmium-induced renal failure in rats

Overexpression of Lias Gene Alleviates Cadmium-Induced Kidney Injury in Mice Involving Multiple Effects: Metabolism, Oxidative Stress, and Inflammation

Oxidative stress is an important mechanism underlying toxicity induced by cadmium (Cd) exposure. However, there are significant differences of the antioxidant baseline in different populations. This means that different human has different intensity of oxidative stress in vivo after exposure to toxicants. LiasH/H mouse is a specific model which is created by genetically modifying the Lias 3'-untranslated region (3'-UTR). LiasH/H mice express high levels of LA and have high endogenous antioxidant capacity which is approximately 150% higher than wild-type C57BL/6 J mice (WT, Lias+/+). But more importantly, they have dual roles of metal chelator and antioxidant. Here, we applied this mouse model to evaluate the effect of endogenous antioxidant levels in the body on alleviating Cd-induced renal injury including Cd metabolism, oxidative stress, and inflammation. In the experiment, mice drank water containing Cd (50 mg/L), for 12 weeks. Many biomarkers of Cd metabolism, oxidative stress, inflammation, and major pathological changes in the kidney were examined. The results showed overexpression of the Lias gene decreased Cd burden in the body of mice, mitigated oxidative stress, attenuated the inflammatory response, and subsequent alleviated cadmium-induced kidney injury in mice.

Low dose cadmium inhibits syndecan-4 expression in glycocalyx of glomerular endothelial cells

Cadmium (Cd) is one of the most polluting heavy metal in the environment. Cd exposure has been elucidated to cause dysfunction of the glomerular filtration barrier (GFB). However, the underlying mechanism remains unclear. C57BL/6J male mice were administered with 2.28 mg/kg cadmium chloride (CdCl2) dissolved in distilled water by oral gavage for 14 days. The expression of SDC4 in the kidney tissues was detected. Human renal glomerular endothelial cells (HRGECs) were exposed to varying concentrations of CdCl2 for 24 h. The mRNA levels of SDC4, along with matrix metalloproteinase (MMP)-2 and 9, were analyzed by quantitative PCR. Additionally, the protein expression levels of SDC4, MMP-2/9, and both total and phosphorylated forms of Smad2/3 (P-Smad2/3) were detected by western blot. The extravasation rate of fluorescein isothiocyanate-dextran through the Transwell was used to evaluate the permeability of HRGECs. SB431542 was used as an inhibitor of transforming growth factor (TGF)-β signaling pathway to further investigate the role of TGF-β. Cd reduced SDC4 expression in both mouse kidney tissues and HRGECs. In addition, Cd exposure increased permeability and upregulated P-Smad2/3 levels in HRGECs. SB431542 treatment inhibited the phosphorylation of Smad2/3, Cd-induced SDC4 downregulation, and hyperpermeability. MMP-2/9 levels increased by Cd exposure was also blocked by SB431542, demonstrating the involvement of TGF-β/Smad pathway in low-dose Cd-induced SDC4 reduction in HRGECs. Given that SDC4 is an essential component of glycocalyx, protection or repair of endothelial glycocalyx is a potential strategy for preventing or treating kidney diseases associated with environmental Cd exposure.

Protective effect of quercetin on cadmium-induced kidney apoptosis in rats based on PERK signaling pathway

BACKGROUND

Cadmium (Cd) is a highly toxic environmental pollutant that can enter the body through bioaccumulation. The kidney is an important target organ for Cd poisoning. Quercetin (Que) is a natural flavonoid compound with free radical scavenging and antioxidant properties. Previous studies showed that Que can alleviate kidney damage caused by Cd poisoning in rats, but the specific mechanism is still unclear.

METHODS

Twenty-four male Sprague-Dawley (SD) rats were divided into four groups: normal saline-treated control group, Cd group treated by intraperitoneal injection of 2 mg/kg b.w. CdCl2, Cd + Que group treated by intraperitoneal injection of 2 mg/kg b.w. CdCl2 and 100 mg/kg b.w. Que, and Que group treated by 100 mg/kg b.w. Que. Four weeks later, the rats were anesthetized with diethyl ether, and blood was taken intravenously. The rats were executed with their necks cut off, and the kidneys were removed. Body weight, kidney organ weight, and glutathione (GSH) and malondialdehyde (MDA) levels were measured. The structure of kidney tissue was observed by hematoxylin and eosin staining, kidney cell apoptosis was detected by TUNEL assay, and the mRNA expression levels of genes related to the PERK signaling pathway were analyzed by RT-PCR.

RESULTS

Compared with the control group, the Cd-treated group exhibited a significant decrease in body weight (P < 0.01). Their kidneys showed a significant increase in the relative organ weight (P < 0.01). Moreover, the MDA and GSH levels increased. Kidney tissue damage and renal cell apoptosis were observed, and the mRNA expression levels of genes related to the PERK signaling pathway significantly increased (P < 0.01). Compared with the Cd-treated group, the Cd + Que group exhibited a significant increase in body weight (P < 0.01) and significant decreases in the relative organ weight, MDA and GSH levels, and mRNA expression levels of genes related to the PERK signaling pathway (P < 0.01). Furthermore, kidney tissue damage and renal cell apoptosis were observed.

CONCLUSION

Cd treatment resulted in rat weight loss, renal edema, and oxidative stress and caused renal tissue damage and cell apoptosis by activating the PERK signaling pathway. Que was able to restore the body weight and renal coefficient of rats. It also alleviated the oxidative stress and kidney tissue damage caused by Cd and the cell apoptosis caused by Cd through inhibiting the PERK signaling pathway. Thus, Que could be considered for the treatment of kidney diseases caused by Cd poisoning.

Cadmium influence on lipid metabolism in Sprague-Dawley rats through linoleic acid and glycerophospholipid metabolism pathways

Cadmium (Cd) is widely distributed in the environment and easy adsorbed by living organisms with adverse effects. Exposure to Cd-contaminated food may disrupt lipid metabolism and increase human health risk. To study the perturbation effect of Cd on lipid metabolism in vivo, 24 male Sprague-Dawley (SD) rats were randomly assigned four groups and treated by Cd chloride solution (0, 1.375 mg/kg, 5.5 mg/kg, 22 mg/kg) for 14 days. The characteristic indexes of serum lipid metabolism were analyzed. Afterwards, untargeted metabolomics analysis was applied to explore the adverse effects of Cd on rats by liquid chromatography coupled with mass spectrometry (LC-MS). The results revealed that Cd exposure obviously decreased the average serum of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) and caused an imbalance of endogenous compounds in the 22 mg/kg Cd-exposed group. Compared with the control group, 30 metabolites with significant differences were identified in the serum. Our results indicated that Cd caused lipid metabolic disorders in rats by disrupting linoleic acid and glycerophospholipid metabolism pathways. Furthermore, there were three kinds of remarkable differential metabolites-9Z,12Z-octadecadienoic acid, PC(20:4(8Z,11Z,14Z,17Z)/0:0), and PC(15:0/18:2(9Z,12Z)), which enriched the two significant metabolism pathways and could be the potential biomarkers.

Antibacterial and Anti-Glucosyltransferase Activity of Verbascum speciosum Against Cariogenic Streptococci

Objectives

Dental caries is a prevalent chronic human infection worldwide and several plants have shown anticariogenic properties through antibacterial activity against oral pathogens. The present study aimed to assess anticariogenic activity of Verbascum speciosum, in search of novel agents for the prevention and treatment of dental caries.

Methods

Hydro-alcoholic extracts from flowers and total aerial parts of the plant were prepared by maceration. Antibacterial activity of the extracts against Streptococcus mutans (ATCC 35668) and Streptococcus sobrinus (ATCC 27607) was investigated by agar diffusion and microdilution techniques. Inhibitory concentration-fifty values of the flowers' extract against Streptococcus mutans glucosyltransferase enzymes were determined. The total flavonoid content of the extracts was determined using an aluminum chloride reaction.

Results

Verbascum speciosum flowers' extract showed significantly higher flavonoid content and antibacterial activity; with minimum inhibitory concentrations of 100 and 200 µg/mL for Streptococcus mutans and Streptococcus sobrinus, respectively. The extract inhibited the synthesis of glucan by cell-associated and extracellular glucosyltransferase enzymes in a dose-dependent manner with higher activity against the extracellular enzyme.

Conclusion

This study indicated effective anticariogenic activity of Verbascum speciosum flowers extract. This extract can be considered as an alternative to current anticaries therapies or an additive to dental care products.

Current Levels of Environmental Exposure to Cadmium in Industrialized Countries as a Risk Factor for Kidney Damage in the General Population: A Comprehensive Review of Available Data

The growing number of reports indicating unfavorable outcomes for human health upon environmental exposure to cadmium (Cd) have focused attention on the threat to the general population posed by this heavy metal. The kidney is a target organ during chronic Cd intoxication. The aim of this article was to critically review the available literature on the impact of the current levels of environmental exposure to this xenobiotic in industrialized countries on the kidney, and to evaluate the associated risk of organ damage, including chronic kidney disease (CKD). Based on a comprehensive review of the available data, we recognized that the observed adverse effect levels (NOAELs) of Cd concentration in the blood and urine for clinically relevant kidney damage (glomerular dysfunction) are 0.18 μg/L and 0.27 μg/g creatinine, respectively, whereas the lowest observed adverse effect levels (LOAELs) are >0.18 μg/L and >0.27 μg/g creatinine, respectively, which are within the lower range of concentrations noted in inhabitants of industrialized countries. In conclusion, the current levels of environmental exposure to Cd may increase the risk of clinically relevant kidney damage, resulting in, or at least contributing to, the development of CKD.

Asperuloside attenuates cadmium-induced toxicity by inhibiting oxidative stress, inflammation, fibrosis and apoptosis in rats

This present study investigated the protective effects of asperuloside (ASP) against cadmium-induced nephrocardiac toxicity. Rats were treated with 50 mg/kg of ASP for five weeks and CdCl2 (5 mg/kg, p.o., once daily) during the last 4 weeks of ASP treatment. The serum levels of blood urea nitrogen (BUN), creatinine (Scr), aspartate transaminase (AST), creatine kinase-MB (CK-MB), troponin T (TnT) and lactate dehydrogenase (LDH) were evealuted. Oxido-inflammatory parameters were detected via malondialdehyde (MDA), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), interleukin-1beta (IL-1β) and nuclear factor kappa B (NF-κB). Additionally, the cardiorenal levels of caspase 3, transforming growth factor-β (TGF-β), α-smooth muscle actin (α-SMA), collagen IV and Bcl2 were measured by ELISA or immunohistochemical assays. The results indicated that ASP significantly decreased Cd-instigated oxidative stress, serum BUN, Scr, AST, CK-MB, TnT and LDH as well as histopathological alterations. Furthermore, ASP notably attenuated Cd-induced cardiorenal and apoptosis and fibrosis by reducing caspase 3 and TGF-β levels, as well as reducing the stain intensity of a-SMA and collagen IV, while increasing Bcl2 intensity. These results revealed that ASP attenuated Cd induced cardiac and renal toxicity which may be attributed to reducing oxidative stress, inflammation, fibrosis and apoptosis.

Cadmium-Induced Kidney Injury: Oxidative Damage as a Unifying Mechanism

Cadmium is a nonessential metal that has heavily polluted the environment due to human activities. It can be absorbed into the human body via the gastrointestinal tract, respiratory tract, and the skin, and can cause chronic damage to the kidneys. The main site where cadmium accumulates and causes damage within the nephrons is the proximal tubule. This accumulation can induce dysfunction of the mitochondrial electron transport chain, leading to electron leakage and production of reactive oxygen species (ROS). Cadmium may also impair the function of NADPH oxidase, resulting in another source of ROS. These ROS together can cause oxidative damage to DNA, proteins, and lipids, triggering epithelial cell death and a decline in kidney function. In this article, we also reviewed evidence that the antioxidant power of plant extracts, herbal medicines, and pharmacological agents could ameliorate cadmium-induced kidney injury. Finally, a model of cadmium-induced kidney injury, centering on the notion that oxidative damage is a unifying mechanism of cadmium renal toxicity, is also presented. Given that cadmium exposure is inevitable, further studies using animal models are warranted for a detailed understanding of the mechanism underlying cadmium induced ROS production, and for the identification of more therapeutic targets.

Modulatory effects of carvacrol against cadmium-induced hepatotoxicity and nephrotoxicity by molecular targeting regulation

AIM

Cadmium (Cd) is a toxic heavy metal that causes severe toxic effects on different tissues including liver and kidney. Therefore the research for alternatives to reduce the damage caused by Cd has substantial importance. This study was performed to examine the possible modulatory effects of carvacrol (CRV) against Cd-induced hepatorenal toxicities and the possible mechanisms underlying these effects.

MATERIALS AND METHODS

In the present study, 35 male Wistar rats were randomly divided into 5 groups. The rats were treated with Cd (25 mg/kg) and treated with CRV (25 and 50 mg/kg body weight) for 7 consecutive days.

KEY FINDINGS

CRV could modulate Cd-induced elevations of ALT, ALP, AST, urea, creatinine, MDA and enhance antioxidant enzymes' activities such as SOD, CAT, and GPx, and GSH's level. CRV also reversed the changes in levels of inflammatory biomarker and apoptotic genes that include NF-κB, Bcl-3, MAPK-14, iNOS, COX-2, MPO, PGE2, Bax, Bcl-2, P53, Caspase-9, Caspase-6 and Caspase-3 in both tissues. The levels of 8-OHdG in the Cd-induced liver and kidney tissues were modulated after CRV treatment. Furthermore, CRV treatment considerably lowered Cd, Na, Fe, and Zn content while increased K, Ca, Mg and Cu contents in both tissues as compared to the Cd-exposed rats.

SIGNIFICANCE

The results of the present study revealed that CRV supplementation could be a promising strategy to protect the liver and kidney tissues against Cd-induced oxidative damage, inflammation and apoptosis.

Rosa persica hydroalcoholic extract improves cadmium-hepatotoxicity by modulating oxidative damage and tumor necrosis factor-alpha status

Rosa persica is a member of the Rosaceae family that has a wide range of pharmacological properties. In this study, the antioxidant and therapeutic potential of this plant was investigated on cadmium (Cd)-induced hepatotoxicity. Rosa persica extract (RPE) was prepared by a maceration method in hydroalcoholic solvent, and its antioxidant properties were determined. Then, 36 mice were divided to six groups and treated for 2 weeks as follows: control, Cd (3 mg/kg), RPE (50 mg/kg), and groups 4-6 received Cd (3 mg/kg) and 12.5, 25, and 50 mg/kg of RPE respectively. The total polyphenol, flavonoids contents, and total antioxidant capacity in RPE were measured 263.4 ± 7.2 mg rutin equivalent/g extract, 72.3 ± 2.3 mg quercetin equivalent/g extract, and 8.46 ± 0.27 μmol ferrous sulfate/g extract, respectively. The in vivo results showed that Cd elicited remarkable hepatic injury that was manifested by the significant increase in serum hepatic enzymes. In addition, Cd significantly increased the levels of lipid peroxidation (LPO) and tumor necrosis factor-alpha (TNF-α) and decreased total thiol molecules (TTM) and total antioxidant capacity (TAC) in hepatic tissue. However, RPE decreased serum hepatic enzyme levels and improved oxidative hepatic damage by lowering the LPO and TNF-α levels and raising TAC and TTM in in Cd-treated groups. Although the RPE increased the metallothionein (MT) protein content, there was no change in MT gene expression. The present study showed that the RPE due to having antioxidant properties might partially prevent hepatic oxidative damage by the improvement of oxidant/antioxidant balance in animals exposed to Cd.

Biochemical and Histological Evidence on the Protective Effects of Allium hirtifolium Boiss (Persian Shallot) as an Herbal Supplement in Cadmium-Induced Hepatotoxicity

MATERIALS AND METHODS

Thirty-six male Wistar rats were divided into six groups: groups 1, 2, and 3 received vehicle, Cd (100 mg/L/day by drinking water), and A. hirtifolium extract (200 mg/kg/day; orally), respectively. Groups 4, 5, and 6 were Cd groups which were treated with A. hirtifolium extract (50, 100, and 200 mg/kg/day, respectively). After 2 weeks, liver enzymes such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) and also oxidative stress biomarkers including lipid peroxidation (LPO), total antioxidant capacity (TAC), total thiol molecule (TTM), and the histopathological changes were determined using standard procedure.

RESULTS

The findings showed that Cd caused a remarkable rise in levels of serum hepatic enzymes such as ALT (P < 0.001), AST (P < 0.01) and ALP (P < 0.001) compared with the control group. In addition, Cd led to the decreasing of the levels of TTM (P < 0.001) and TAC (P < 0.001) and increasing of LPO (P < 0.001) in liver tissue in comparison with the control group. In this regard, remarkable vascular congestion, hepatocellular degeneration, and vacuolization were observed in hepatic tissue of Cd-treated rats. Following the administration of A. hirtifolium extract, a significant improvement was observed in the functional and oxidative stress indices of hepatic tissue alongside histopathologic changes.

CONCLUSION

The current study indicated that the A. hirtifolium extract might prevent hepatic oxidative injury by improving oxidant/antioxidant balance in rats exposed to Cd.

Plant Extracts and Isolated Compounds Reduce Parameters of Oxidative Stress Induced by Heavy Metals: An up-to-Date Review on Animal Studies

BACKGROUND

Heavy metals are elements that are naturally found in the earth. They are used in many modern-day applications in agriculture, medicine, and industry. Heavy metal poisoning occurs when the body's soft tissues absorb too much of a particular metal. The heavy metals of interest for this review paper were cadmium, arsenic, mercury, and lead since these are the most common metals that the human body can absorb in toxic amounts. Different plant species were investigated in recent years for their effect on oxidative stress parameters after intoxication with heavy metals.

OBJECTIVES

This review paper is focused on the current update to research on heavy metals induced oxidative stress in animal models and improvement of the oxidative stress parameters upon/co-/after treatment with different plant extracts and isolated compounds.

METHODS

The available literature was screened for the novel data regarding the influence of plant extracts and compounds on heavy metals induced oxidative stress. For that purposes Scopus database was used, looking for the publications in the last 5-10 years with the key terms: plant extracts, oxidative stress, in vivo, cadmium, lead, mercury and arcenic.

RESULTS

Various parameters of oxidative stress were investigated, and their improvement with plant extracts/ compounds was observed in the brain, lungs, kidneys, liver, uterus, testis, thymus, spleen, heart, skin and blood of experimental animals. Common parameters used to determine oxidative stress in animals were: superoxide dismutase; catalase; reduced glutathione; glutathione reductase; glutathione-S-transferase; glutathione peroxidase; lipid peroxidation; oxidized glutathione; malondialdehyde; xanthine oxidase; nonprotein-soluble thiol; thioredoxin reductase; total sulphydryl group; nitric oxide; γ-glutamyl cysteine synthetase.

CONCLUSION

The most investigated species for antioxidant effects upon intoxication with heavy metals seem to be Allium sp., Bacopa monniera, Camellia sinensis, Moringa oleifera, Vitis vinifera and Zingiber officinale. According to literature data, the most promising effect to alleviate symptoms of intoxication was achieved with proanthocyanidins obtained from Vitis vinifera.

Hepatoprotective potential and antioxidant activity of Allium tripedale in acetaminophen-induced oxidative damage

Allium tripedale (A. tripedale) is a species of wild Allium native to northwest Iran that its hepatoprotective effects have not yet been confirmed. This study investigated the effect of A. tripedale plant against acetaminophen (APAP)-induced acute liver damage. After preliminary studies, the A. tripedale methanol fraction (ATMF) was selected for in vivo study. Thirty-six rats were divided into six groups of 6 each and treated by gavage as follows: groups 1 and 2 received normal saline; group 3 received 400 mg/kg of ATMF; and groups 4-6 were treated with 100, 200, and 400 mg/kg of ATMF, respectively. After two consecutive weeks, except groups 1 and 3, rats were administered with an oral single dose of APAP (2 g/kg). After 48 h, blood and liver samples were collected for histological and biochemical examinations. The results showed that APAP caused a significant increase in alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and alkaline phosphatase serum levels, lipid peroxidation (all with P < 0.001) and hepatic nitric oxide (P < 0.01). In addition, APAP led to the depletion of the total antioxidant capacity, total thiol group (both with P < 0.001), and structural alterations in the hepatic tissue. Following administration of ATMF extract, a significant improvement was observed in the functional and oxidative stress markers of hepatic tissue alongside histopathologic changes. In conclusion, the present study showed that the administration of ATMF might prevent hepatic oxidative damage by improving oxidant/antioxidant balance in animals exposed to APAP.