Protective effect of Potentilla anserina polysaccharide on cadmium-induced nephrotoxicity in vitro and in vivo

A systematic review on botany, ethnopharmacology, phytochemistry and pharmacology of Potentilla anserina L

ETHNOPHARMACOLOGICAL RELEVANCE

Potentilla Anserina Linnaeus, a traditional Chinese herb with ethnic characteristics, is considered a superior material by the people of Qinghai and Tibet. Traditionally, it has been used to invigorate the spleen, quench thirst, tonify the blood, astringing to stop bleeding, and relieve diarrhea. This is the reason for its frequent usage in treating spleen deficiency, diarrhea, and various bleeding disorders. At the same time, P. anserina is often consumed as food by the Tibetan people to obtain nourishment and health benefits.

AIM OF THE REVIEW

The present review provides a systematic description of P. anserina, covering its botany, ethnopharmacology, phytochemical constituents, and various pharmacological activities of extracts. This overview aims to provide insights into research directions and potential applications of P. anserina.

MATERIALS AND METHODS

Information on P. anserina was gathered through various sources, including Google Scholar, PubMed, Elsevier, CNKI, and Web of Science. In addition, information was available from native texts and prominent ethnopharmacologists.

RESULTS

So far, 154 different chemical substances have been isolated and identified from P. anserina, with tannins, flavonoids, and triterpenes accounting for the majority. Polysaccharides and triterpenes are the main material components responsible for the pharmacological activity of P. anserina. Research shows that P. anserina exhibits rich pharmacological activities, including antioxidant, antiviral, blood tonic, immune regulation, cardiovascular system treatment, diabetes treatment, and liver protection.

CONCLUSIONS

Some traditional applications of P. anserina have been confirmed. However, due to incomplete evaluation indicators and other reasons, further in vitro and in vivo studies are needed to clarify its pharmacological evaluation, which remains a focus of future research. Additionally, we recommend that future studies concentrate on the quality control and safety evaluation of P. anserina to address research gaps and offer theoretical support for the plant's potential functions and clinical applications.

A Tripeptide (Ser-Arg-Pro, SRP) from Sipunculus nudus L. Improves Cadmium-Induced Acute Kidney Injury by Targeting the MAPK, Inflammatory, and Apoptosis Pathways in Mice

Cadmium (Cd) is a toxic heavy metal that causes nephrosis, including acute kidney injury. To prevent and treat acute kidney injury (AKI) following Cd exposure, a tripeptide, Ser-Arg-Pro (SRP), from Sipunculus nudus L. was employed, and its potential efficacy in AKI was assessed. Oral administration of SRP significantly alleviated Cd-induced kidney damage, leading to improved renal function and the attenuation of structural abnormalities. A network pharmacology analysis revealed the potential of SRP in renal protection by targeting various pathways, including mitogen-activated protein kinase (MAPK) signaling, inflammatory response, and apoptosis pathways. Mechanistic studies indicated that SRP achieves renal protection by inhibiting the activation of MAPK pathways (phosphorylation of p38, p56, ERK, and JNK) in the oxidative stress cascade, suppressing inflammatory responses (iNOS, Arg1, Cox2, TNF-α, IL-1β, and IL-6), and restoring altered apoptosis factors (caspase-9, caspase-3, Bax, and Bcl-2). Hence, SRP has the potential to be used as a therapeutic agent for the treatment of Cd-induced nephrotoxicity.

Molecular docking and molecular dynamics simulation of wheat gluten-derived antioxidant peptides acting through the Keap1-Nrf2 pathway

BACKGROUND

In our previous study, we successfully identified five peptides from wheat gluten: Ala-Pro-Ser-Tyr (APSY), Leu-Tyr (LY), Pro-Tyr (PY), Arg-Gly-Gly-Tyr (RGGY) and Tyr-Gln (YQ). Molecular docking and molecular dynamics simulation methods were employed to investigate the interaction between these antioxidant peptides and the Kelch-like ECH-associated protein 1 (Keap1 protein), revealing the molecular mechanism of their non-competitive binding. In addition, the total antioxidant capacity of the five peptides was determined using the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) method.

RESULTS

The affinities of APSY, LY, PY, RGGY and YQ were -8.9, -8.3, -8.5, -9.1 and - 7.9 kcal mol-1, respectively. The five peptides effectively bound to Keap1 protein through hydrogen, π-σ, π-alkyl and alkyl interactions. Significant roles were observed for the P1 pocket residue ARG-415 and the P3 pocket residue ALA-556 in the interactions of the Keap1-peptide complexes. Molecular dynamics simulations further elucidated the dynamic process of peptide binding to the Keap1 protein. All five peptides formed stable complexes with Keap1 protein, with van der Waals forces playing crucial roles in these complex systems, indicative of the peptides' strong binding ability to Keap1 protein. The van der Waals forces were -178.74, -123.11, -134.36, -132.59, and -121.44 kJ mol-1 for the Keap1-APSY, Keap1-LY, Keap1-PY, Keap1-RGGY and Keap1-YQ complexes, respectively. These peptides exhibited excellent antioxidant effects. Among them, the YQ peptide exhibited the highest total antioxidant capacity, with an activity value of 1.18 ± 0.06 mmol Trolox equivalent (TE) L-1 at a concentration of 0.10 mg mL-1. The RGGY, PY, LY and APSY peptides followed in descending order, with activity values of 0.91 ± 0.05, 0.72 ± 0.06, 0.62 ± 0.04 and 0.60 ± 0.05 mmol TE L-1, respectively.

CONCLUSION

These results unveiled the molecular mechanism by which the five antioxidant peptides act on active pockets through the Keap1-Nrf2 signaling pathway, providing a theoretical basis for the development of antioxidants. © 2024 Society of Chemical Industry.

Reversal Effects of Royal Jelly and Propolis Against Cadmium-Induced Hepatorenal Toxicity in Rats

Heavy metal toxicity is an exponentially growing health problem. In this study, we aimed to assess the protective properties of propolis and royal jelly against cadmium adverse effects. Thirty-two adult male rats were included in our study; kidney and liver functions, histopathological changes, and the level of oxidative stress were evaluated in rats exposed to a daily dose of 4.5 mg cadmium per kilogram of body weight for 1 month and those cotreated simultaneously with either propolis (50 mg/kg/day) or royal jelly (200 mg/kg/day) with cadmium compared to control animals. Cadmium-mediated hepatorenal toxicity was manifested as per the increased oxidative stress, function deterioration, and characteristic histopathological aberrations. The supplementation of royal jelly or propolis restores most of the affected parameters to a level similar to the control group. However, the parameters describing the grade of DNA damage and the interleukin-1β expression in the liver, as well as the levels of malondialdehyde and metallothionein, were slightly elevated compared to controls, despite the regular use of royal jelly or propolis. It is worth noting that better results were found in the case of royal jelly compared to propolis administration. Most likely, the ability of both products to chelate cadmium and contribute in reducing oxidative stress is of great importance. However, further investigations are needed to complement the knowledge about the expected nutritional and medicinal values.

Antioxidant activity of Carica papaya & Persea americana fruits against cadmium induced neurotoxicity, nephrotoxicity, and hepatotoxicity in rats with a computational approach

BACKGROUND

Cadmium is widely reported to interfere with the proper functioning of cells by disrupting cellular redox balance, causing apoptosis, and leading to hepatocellular damage, neurotoxicity, pulmonary edema, cancer, and cardiac and neurodegenerative diseases. Treatment of Cd toxicity with drugs brings undesirable side effects, making it necessary to remove Cd from the body safely without harmful effects.

OBJECTIVE

This study aimed to determine how Cd causing malfunctioning of cells could be treated with antioxidant-rich avocado and papaya fruit juices. This work fixated on elucidating and comparing the effects of avocado and papaya fruit juice on Cd-dependent impairment in memory and spatial learning. In addition, various markers of tissue damage, such as the concentration of biomarkers in liver and kidney tissue, the expression of antioxidant enzymes and Cd-induced lipid peroxidation, were analyzed.

METHODOLOGY

in silico studies of the phytochemical constituents of avocado and papaya (ligands) were docked against antioxidant enzymes Catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) as macromolecules showed strong hydrogen binding with significant binding capacities. To develop the Cd in vivo model, rats were administered CdCl2 (200 ppm) in drinking water for 7 weeks. After induction of Cd toxicity, rats were post-treated with avocado and papaya (10% w/v each) in a standard diet. After post-treatment, memory and learning were assessed using the Morris water maze behavioural test. Biochemical tests for liver and kidney biomarkers were monitored. To determine the level of ROS, lipid peroxidation was determined by Malondialdehyde (MDA) assay. Gene expression of SOD, CAT and GPx were determined via qRT-PCR.

RESULTS

This study demonstrated that Cd accumulation in the liver, kidney and hippocampal tissues was reduced after treatment with avocado and papaya. SOD, CAT and GPX gene expression were upregulated after avocado and papaya juice treatment. Moreover, a comparative analysis between avocado and papaya fruit juices clarified that papaya has more active potential for improving memory and learning, upregulating the expression of antioxidant enzymes, and reducing lipid peroxidation in the liver, kidney, and hippocampus.

CONCLUSION

This study suggests that a diet containing papaya and avocado can help treat the lethal effects caused by Cd. Because their active constituents can improve health at the cellular and molecular levels.

Mechanisms of Cadmium Neurotoxicity

Cadmium is a heavy metal that increasingly contaminates food and drink products. Once ingested, cadmium exerts toxic effects that pose a significant threat to human health. The nervous system is particularly vulnerable to prolonged, low-dose cadmium exposure. This review article provides an overview of cadmium's primary mechanisms of neurotoxicity. Cadmium gains entry into the nervous system via zinc and calcium transporters, altering the homeostasis for these metal ions. Once within the nervous system, cadmium disrupts mitochondrial respiration by decreasing ATP synthesis and increasing the production of reactive oxygen species. Cadmium also impairs normal neurotransmission by increasing neurotransmitter release asynchronicity and disrupting neurotransmitter signaling proteins. Cadmium furthermore impairs the blood-brain barrier and alters the regulation of glycogen metabolism. Together, these mechanisms represent multiple sites of biochemical perturbation that result in cumulative nervous system damage which can increase the risk for neurological and neurodegenerative disorders. Understanding the way by which cadmium exerts its effects is critical for developing effective treatment and prevention strategies against cadmium-induced neurotoxic insult.

Alleviative effect of melatonin against the nephrotoxicity induced by cadmium exposure through regulating renal oxidative stress, inflammatory reaction, and fibrosis in a mouse model

Chronic cadmium (Cd) exposure causes severe adverse health effects on the human body, especially the kidney tissue. Studies have demonstrated oxidative stress to be involved in renal pathological variations after exposure to Cd, but few effective treatments are available for the disease yet. Therefore, the present study was carried out to investigate the potential therapeutic intervention and its underlying molecular mechanisms of melatonin (MT), a natural antioxidant with multiple biological activities, against renal injury caused by Cd exposure in mice. C57BL/6 male mice (eight-week-old) were intragastrically administered with CdCl2, MT, or both for 30 days. Biochemical analysis showed that MT intervention significantly improved the SOD, GSH, and CAT activities while markedly decreasing the kidney MDA content of the mice exposed to Cd. Histological examination indicated that Cd exposure resulted in the atrophy of the renal glomerular, the degeneration and dilation of tubules, and the accumulation of fibrocytes. By contrast, MT administration effectively ameliorated the histological outcome of the injured kidney tissue. Moreover, administrating MT significantly inhibited proinflammatory cytokines TNF-α and iNOS expression in Cd-treated mice. Further, MT treatment markedly suppressed the expressions of renal fibrosis-related factors TGF-β1, α-SMA, and collagen Ⅰ in the injured renal tissue and the accumulation and development of renal fibrosis. In addition, the administration of MT significantly reduced the expression of caspase-3 and cell apoptotic death in the kidney tissue of Cd-exposed mice. In all, the data showed that MT has a compelling therapeutic potential in alleviating the pathological variations of renal injury caused by Cd exposure.

Enzyme-assisted extraction, characterization, and in vitro antioxidant activity of polysaccharides from Potentilla anserina L

Introduction

Potentilla anserina (Potentilla anserina L.), also known as ginseng fruit, is a plant that can be used as both medicine and food. Potentilla anserina L. has high medical value in Chinese medicine, such as strengthening the spleen and stomach, replenishing qi and blood, and astringing hemostasis.

Methods

In this study, polysaccharides of Potentilla anserina L. were extracted from the root using an enzyme-assisted extraction method. According to the principle of Box-Behnken design, response surface methodology was designed to optimize the extraction conditions. Fourier transform infrared spectroscopy and scanning electron microscopy were used to investigate the structure and appearance of Potentilla anserina L. polysaccharides. The monosaccharide composition of Potentilla anserina L. polysaccharides was determined using high-performance liquid chromatography. The antioxidant activities were also studied.

Results

Under the optimal extraction conditions (the ratio of solid to liquid, 1:15; ratio of cellulase to pectinase, 1:2; extraction pH, 8.0; enzyme reaction temperature, 60°C), the extraction yield of Potentilla anserina L. polysaccharides was 19.80 ± 0.01%, equal to the model prediction value 19.84%. The data of Fourier transform infrared spectrum, scanning electron microscopy, and high-performance liquid chromatography showed that the Potentilla anserina L. polysaccharide was a kind of α-pyran polysaccharide, mainly consisting of galactose, glucose, rhamnose, and arabinose. The antioxidant results showed that Potentilla anserina L. polysaccharides had a strong hydroxyl radical scavenging ability (IC₅₀ = 0.367 mg/mL), superoxide anion scavenging ability (IC₅₀ = 45.017 mg/mL), and a certain degree of total reducing ability.

Discussion

Enzyme-assisted extraction is an efficient method to extract Potentilla anserina L. polysaccharides. The Potentilla anserina L. polysaccharides could have potential use in functional foods as a natural antioxidant.

Flammulina velutipes polysaccharide counteracts cadmium-induced gut injury in mice via modulating gut inflammation, gut microbiota and intestinal barrier

Cadmium (Cd), as Group I carcinogen, can induce damage to various organs including the gut. It is of great importance to meet the rising demand for effective therapies against Cd-induced damage and investigate the mechanism. Flammulina velutipes is a popular edible mushroom, despite the well-known health benefits of Flammulina velutipes, little is known about the effect of its polysaccharide (FVP) against CdCl₂-intestinal injury. In this study, a FVP (uronic acid, 5.10 %; degree of methylation, 41.24 %) was produced via hot water extraction (85 °C) and ethanol precipitation. The FVP contained eight major monosaccharides and exhibited good thermal stability at temperatures lower than 139.73 °C. FVP (100 mg/kg b. w., gavage for 4 weeks) alleviated CdCl₂ (1.5 mg/kg b. w., gavage for 4 weeks)-induced intestinal inflammation and apoptosis, intestinal permeability alteration and intestinal barrier disruption. FVP increased the abundance of Bacteroides, whilst decreasing the abundance of Desulfovibrionales and Clostridium. FVP also restored the levels of short-chain fatty acids (SCFAs), including acetic, propionic, isobutyric, butyric, isovaleric and valeric acids. Correlation analysis indicated the interplays among the FVP, gut microbes, SCFAs, intestinal barrier/cells and gut inflammation. FVP enhances the metabolic functions of gut microbiota via functional pathways analyzed by KEGG database. Furthermore, gut microbial transplantation of FVP + CdCl₂ group mice partially alleviated CdCl₂ caused-gut damage. Thus, FVP may be an effective therapeutic agent against CdCl₂-induced gut damage via SCFA-mediated regulation of intestinal inflammation and gut microbiota-related energy metabolism. This study may open a new avenue for developing alternative strategies to prevent CdCl₂-caused injury.

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.

Potentilla anserina polysaccharide alleviates cadmium-induced oxidative stress and apoptosis of H9c2 cells by regulating the MG53-mediated RISK pathway

Oxidative stress plays a crucial role in cadmium (Cd)-induced myocardial injury. Mitsugumin 53 (MG53) and its mediated reperfusion injury salvage kinase (RISK) pathway have been demonstrated to be closely related to myocardial oxidative damage. Potentilla anserina L. polysaccharide (PAP) is a polysaccharide with antioxidant capacity, which exerts protective effect on Cd-induced damage. However, it remains unknown whether PAP can prevent and treat Cd-induced cardiomyocyte damages. The present study was desgined to explore the effect of PAP on Cd-induced damage in H9c2 cells based on MG53 and the mediated RISK pathway. For in vitro evaluation, cell viability and apoptosis rate were analyzed by CCK-8 assay and flow cytometry, respectively. Furthermore, oxidative stress was assessed by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining and using superoxide dismutase (SOD), catalase (CAT), and glutathione/oxidized glutathione (GSH/GSSG) kits. The mitochondrial function was measured by JC-10 staining and ATP detection assay. Western blot was performed to detect the expression of proteins related to MG53, the RISK pathway, and apoptosis. The results indicated that Cd increased the levels of reactive oxygen species (ROS) in H9c2 cells. Cd decreased the activities of SOD and CAT and the ratio of GSH/GSSG, resulting in decreases in cell viability and increases in apoptosis. Interestingly, PAP reversed Cd-induced oxidative stress and cell apoptosis. Meanwhile, Cd reduced the expression of MG53 in H9c2 cells and inhibited the RISK pathway, which was mediated by decreasing the ratio of p-Akt^Ser473/Akt, p-GSK3β^Ser9/GSK3β and p-ERK1/2/ERK1/2. In addition, Cd impaired mitochondrial function, which involved a reduction in ATP content and mitochondrial membrane potential (MMP), and an increase in the ratio of Bax/Bcl-2, cytoplasmic cytochrome c/mitochondrial cytochrome c, and Cleaved-Caspase 3/Pro-Caspase 3. Importantly, PAP alleviated Cd-induced MG53 reduction, activated the RISK pathway, and reduced mitochondrial damage. Interestingly, knockdown of MG53 or inhibition of the RISK pathway attenuated the protective effect of PAP in Cd-induced H9c2 cells. In sum, PAP reduces Cd-induced damage in H9c2 cells, which is mediated by increasing MG53 expression and activating the RISK pathway.

The protective mechanism of a novel polysaccharide from Lactobacillus-fermented Nostoc commune Vauch. on attenuating cadmium-induced kidney injury in mice

A novel polysaccharide (NCVP-F) from Lactobacillus-fermented Nostoc commune Vauch. was obtained to investigate its underlying mechanism in cadmium-induced kidney injury. Results indicated that in comparison with NCVP, NCVP-F with lower molecular weight of 365.369 kDa, exhibited higher mole percentage of Man and Glc-UA, whereas slightly lower mole percentage of other monosaccharides. NCVP-F is a α-pyran polysaccharide similar to NCVP. Meanwhile, NCVP-F can more effectively alleviate hepatorenal injury (ALT, AST, TG, BUN and SCr) and kidney tissue lesions in Cd-injured mice model by increasing antioxidant enzyme activity (SOD, GSH and GSH-Px), inhibiting cytokines levels (IL-6, IL-1β, TNF-α and IL-18). In addition, NCVP-F effectively inhibited apoptosis proteins (Bax, cytochrome c, a-caspase-9 and a-caspase-3) and enhanced anti-apoptotic protein (Bcl-2) probably via activating PI3K/AKT/mTOR pathway in the Cd-injury kidney. Furthermore, 16S rRNA sequencing results indicated that NCVP-F better enriched Lachnospiraceae, reduced Muribaculaceae, Alloprevotella and Blautia to regulate Cd-induced gut microbiota disorders, which was probably down-regulated 7 pathways including apoptosis and lipopolysaccharide biosynthesis, and up-regulated 63 pathways, such as carbohydrate metabolism and lipid metabolism. This study suggested that applying functional NCVP-F prepared by biotransformation with low molecular weight might be more beneficial.

Advances in health-promoting effects of natural polysaccharides: Regulation on Nrf2 antioxidant pathway

Natural polysaccharides (NPs) possess numerous health-promoting effects, such as liver protection, kidney protection, lung protection, neuroprotection, cardioprotection, gastrointestinal protection, anti-oxidation, anti-diabetic, and anti-aging. Nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant pathway is an important endogenous antioxidant pathway, which plays crucial roles in maintaining human health as its protection against oxidative stress. Accumulating evidence suggested that Nrf2 antioxidant pathway might be one of key regulatory targets for the health-promoting effects of NPs. However, the information concerning regulation of NPs on Nrf2 antioxidant pathway is scattered, and NPs show different regulatory behaviors in their different health-promoting processes. Therefore, in this article, structural features of NPs having regulation on Nrf2 antioxidant pathway are overviewed. Moreover, regulatory effects of NPs on this pathway for health-promoting effects are summarized. Furthermore, structure-activity relationship of NPs for health-promoting effects by regulating the pathway is preliminarily discussed. Otherwise, the prospects on future work for regulation of NPs on this pathway are proposed. This review is beneficial to well-understanding of underlying mechanisms for health-promoting effects of NPs from the view angle of Nrf2 antioxidant pathway, and provides a theoretical basis for the development and utilization of NPs in promoting human health.

Oxidative Stress and Mitochondrial Dysfunction in Chronic Kidney Disease

The kidney contains many mitochondria that generate ATP to provide energy for cellular processes. Oxidative stress injury can be caused by impaired mitochondria with excessive levels of reactive oxygen species. Accumulating evidence has indicated a relationship between oxidative stress and kidney diseases, and revealed new insights into mitochondria-targeted therapeutics for renal injury. Improving mitochondrial homeostasis, increasing mitochondrial biogenesis, and balancing mitochondrial turnover has the potential to protect renal function against oxidative stress. Although there are some reviews that addressed this issue, the articles summarizing the relationship between mitochondria-targeted effects and the risk factors of renal failure are still few. In this review, we integrate recent studies on oxidative stress and mitochondrial function in kidney diseases, especially chronic kidney disease. We organized the causes and risk factors of oxidative stress in the kidneys based in their mitochondria-targeted effects. This review also listed the possible candidates for clinical therapeutics of kidney diseases by modulating mitochondrial function.

Potentilla anserine L. polysaccharide protects against cadmium-induced neurotoxicity

Cadmium is a toxic metal that can damage the brain and other organs. This study aimed to explore the protective effects of Potentilla anserine L. polysaccharide (PAP) against CdCl2-induced neurotoxicity in N2a and SH-SY5Y cells and in the cerebral cortex of BALB/c mice. In addition, we aimed to identify the potential mechanisms underlying these protective effects. Relative to CdCl2 treatment alone, pretreatment with PAP prevented the reduction in cell viability evoked by CdCl2, decreased rates of apoptosis, promoted calcium homeostasis, decreased ROS accumulation, increased mitochondrial membrane potential, inhibited cytochrome C and AIF release, and prevented the cleavage of caspase-3 and PARP. In addition, PAP significantly decreased the CdCl2-induced phosphorylation of CaMKII, Akt, and mTOR. In conclusion, PAP represents a potential therapeutic agent for the treatment of Cd-induced neurotoxicity, functioning in part via attenuating the activation of the mitochondrial apoptosis pathway and the Ca2+-CaMKII-dependent Akt/mTOR pathway.

Cadmium-Induced Kidney Injury in Mice Is Counteracted by a Flavonoid-Rich Extract of Bergamot Juice, Alone or in Association with Curcumin and Resveratrol, via the Enhancement of Different Defense Mechanisms

Cadmium (Cd) represents a public health risk due to its non-biodegradability and long biological half-life. The main target of Cd is considered the kidney, where it accumulates. No effective treatment for Cd poisoning is available so that several therapeutic approaches were proposed to prevent damages after Cd exposure. We evaluated the effects of a flavonoid-rich extract of bergamot juice (BJe), alone or in association with curcumin (Cur) and resveratrol (Re), in the kidney of mice exposed to cadmium chloride (CdCl₂). Male mice were administered with CdCl₂ and treated with Cur, Re, or BJe alone or in combination for 14 days. The kidneys were processed for biochemical, structural and morphometric evaluation. Cd treatment significantly increased urea nitrogen and creatinine levels, along with tp53, Bax, Nos2 and Il1b mRNA, while reduced that of Bcl2, as well as glutathione (GSH) content and glutathione peroxidase (GPx) activity. Moreover, Cd caused damages to glomeruli and tubules, and increased Nrf2, Nqo1 and Hmox1 gene expression. Cur, Re and BJe at 40 mg/kg significantly improved all parameters, while BJe at 20 mg/kg showed a lower protective effect. After treatment with the associations of the three nutraceuticals, all parameters were close to normal, thus suggesting a new potential strategy in the protection of renal functions in subjects exposed to environmental toxicants.

Protective effect of melatonin against chronic cadmium-induced hepatotoxicity by suppressing oxidative stress, inflammation, and apoptosis in mice

Cadmium (Cd) is a widespread environmental heavy metal pollutant that has high toxicity to human health. Cd accumulates in the liver and results in oxidative stress and inflammatory reactions. Melatonin (MT), a hormone exhibiting strong antioxidative properties, has been proved to have hepatoprotective effect against both acute and chronic liver injury. However, the molecular mechanism underlying MT's hepatoprotective effect against Cd-induced liver injury remain not fully understood. In this study, the potential protective effect of MT on Cd-induced hepatic injury was investigated. Adult male C57BL/6 mice were randomly divided into four groups: control, CdCl2, MT, and CdCl2 plus MT groups. Animals were daily treated with either CdCl2 (5 mg/kg) or MT (10 mg/kg) or both through intragastric administration for 30 consecutive days. Serum enzymatic analysis indicated that treatment mice with Cd significantly increased AST, ALT, LDH and ALP levels, by contrast, MT treatment resulted in significant decreases of AST, ALT, LDH and ALP levels in the serum of Cd treated mice. By biochemical analysis, it was found that MT treatment significantly increased the activities of SOD, GSH, GST, CAT and GR, while significantly decreased the contents of MDA in the liver tissue of Cd treated mice. Moreover, MT treatment also suppressed the Cd-induced inflammation by reducing the inflammatory mediators, including IL-1β, IL-6, TNF-α and iNOS. Furthermore, MT treatment ameliorated the Cd-induced histopathological variations of liver tissue, which was confirmed by the biochemical and molecular data. It is clear from the results of this study that MT exerts hepatoprotective effect by improving the redox state, suppressing inflammatory reaction and cell apoptosis as well as ameliorating the performance of liver tissue histopathology, which is eventually reflected by the improvement of liver function in mice.

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.

Potentilla anserine L. polysaccharide inhibits cadmium-induced neurotoxicity by attenuating autophagy

Cadmium (Cd), a heavy metal with cytotoxicity, can activate autophagy. This study aimed to explore the effects and mechanisms of Potentilla anserine L. polysaccharide (PAP) on autophagy in N2a cells, primary neurons, and the brain of BALB/c mice exposed to Cd. The CCK-8 assay results showed that the cell viability decreased and the number of acidic vesicular organelles, autophagic vacuoles, lysosomes, and dysfunctional mitochondria increased in the cytoplasm of Cd-exposed N2a cells and primary neurons, as revealed by acridine orange staining, monodansylcadaverine staining, and transmission electron microscopy. PAP mitigated Cd-induced neuronal death and characteristic changes in autophagy. The expression of LC3 IILC3 II, Bcl-2, p62, Beclin-1, and PI3K class III was examined by Western blot analysis. Furthermore, the PI3K inhibitor (LY294002 or 3-MA) and/or PAP reversed the Cd-induced upregulated expression of LC3 II, Beclin-1, and PI3K class III, with a synergy between PI3K inhibitor and PAP against Cd-induced autophagy. The findings suggested that PAP partially prevented Cd-induced autophagic cell death in neurons by inhibiting the PI3K class III/Beclin-1 signaling pathway in vitro and in vivo.

Albicanol antagonizes Cd-induced apoptosis through a NO/iNOS-regulated mitochondrial pathway in chicken liver cells

Cadmium (Cd) induces hepatocyte injury by oxidative stress. Albicanol is a sesquiterpenoid extracted from the medicinal plant Dryopteris fragrans that has previously been shown to exhibit anti-aging and antioxidant activity. In this study, we explored the mechanism of albicanol inhibition of the Cd-induced apoptosis of chicken hepatoma cells (LMH) by treating these cells with CdCl2 (25 μM) and/or albicanol (2.5 × 10-5 μg mL-1) for 24 h. Under Cd treatment, the research results showed that the apoptosis rate markedly increased in LMH cells. In addition, the iNOS activity and NO content increased significantly, which promoted the expressions of genes associated with the mitochondrial apoptosis pathway (Bax, CytC, Caspase-3 and Caspase-9) and inhibited the expression of Bcl-2 in this pathway. However, Cd + albicanol co-treatment significantly reduced the apoptosis rate and the expressions of iNOS and genes associated with the mitochondrial apoptosis pathway (Bax, CytC, Caspase-3 and Caspase-9), and promoted the expression of Bcl-2 in this pathway. In addition, molecular docking supported a link between the albicanol ligand and the iNOS receptor. These results indicated that albicanol can inhibit Cd-induced apoptosis by regulating the NO/iNOS-mediated mitochondrial pathway.

Recent phytochemical and pharmacological advances in the genus Potentilla L. sensu lato - An update covering the period from 2009 to 2020

ETHNOPHARMACOLOGICAL RELEVANCE

Potentilla plants are still common herbal medicines used in folk medicine. This review provides an update of research undertaken on Potentilla from 2009 until 2020.

AIM OF THE STUDY

This comprehensive review considers biological updates, recent advances in phytochemical and pharmacological research, and toxicological reports on Potentilla sensu lato based on available data since 2009.

METHODS

A literature search was conducted using available databases including ScienceDirect, PubMed, Scopus, Web of Science, China National Knowledge Infrastructure and Google Scholar.

RESULTS

Until now, more than 210 new and known compounds, including flavonoids, tannins, triterpenes and phenolic compounds, have been confirmed and elucidated for numerous Potentilla species, i.e., in the underground and aerial parts of this genus. Modern pharmacology studies have revealed that those structures are responsible for a broad spectrum of pharmacological activities, such as anti-neoplastic, antihyperglycemic, anti-inflammatory, antioxidant, hepatoprotective, neuroprotective, antibacterial and anti-yeast effects.

CONCLUSIONS

However, in vitro studies must be re-considered due to the discovery of urolithins and their origins, including microbiota, which can lead to different results when applying Potentilla species and their extracts to in vivo conditions. Thus, future research should focus more on in vivo and particularly clinical studies to confirm the validity and safety of traditional uses. Particularly, the use of Potentilla alba extracts in the treatment of thyroid gland disorders should be further explored to confirm the underlying mechanism of their action, efficacy and safety. In addition, more clinical studies should focus on Potentilla erecta rhizome extracts for application as herbal remedies against dysentery, diarrhoea and inflammation of the skin.

Potentilla anserina L. developmental changes affect the rhizosphere prokaryotic community

Plant roots and soil prokaryotes primarily interact with each other in the rhizosphere. Changes in the rhizosphere prokaryotic structure are influenced by several factors. In this study, the community structure of the Potentilla anserina L. rhizosphere prokaryotes was identified and evaluated by high-throughput sequencing technology in different continuous cropping fields and developmental stages of the plant. In total, 2 archaeal (Euryarchaeota and Thaumarchaeota) and 26 bacterial phyla were identified in the P. anserina rhizosphere. The bacterial community was mainly composed of Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Gemmatimonadetes, Planctomycetes, Proteobacteria, and Verrucomicrobia. Moreover, the prokaryotic community structure of the rhizosphere varied significantly during plant development. Our results provide new insights into the dynamics of the P. anserina rhizosphere prokaryotic community and may provide useful information for enhancing the growth and development of P. anserina through artificial control of the soil prokaryotes.

Enhanced Cytotoxicity of Cadmium by a Sulfated Polysaccharide from Abalone

Consumption of seafood is a common route of cadmium ion (Cd²⁺) exposure to consumers. The seafood matrices may alter the toxicity profile of Cd²⁺ due to the interaction between Cd²⁺ and biomacromolecules in seafood. In this study, enhanced cytotoxicity of Cd²⁺ was found in the presence of an abalone gonad sulfated polysaccharide (AGSP) and the mechanism was investigated at a metabolic level. The formation of the AGSP-Cd²⁺ complex was demonstrated by isothermal titration calorimetry. The level of reactive oxygen species (ROS) increased and mitochondrial membrane potential reduced upon exposure to the AGSP-Cd²⁺ complex as compared with those of Cd²⁺ exposure. The decreased cell viability after incubation with the AGSP-Cd²⁺ complex also suggested enhanced Cd²⁺ toxicity induced by AGSP. The metabolomics and lipidomics analysis revealed that, compared with the Cd²⁺ group, the AGSP-Cd²⁺ downregulated the phospholipid metabolism and resulted in more serious damage in the cellular membrane. The lipid metabolism disorder, in turn, amplified the generation of ROS, leading to a decrease in cell viability. These results provided new evidence of the enhanced Cd²⁺ toxicity upon interaction with seafood polysaccharides, and much attention should be paid to the effect of food ingredients on heavy metal ion toxicity.

Platycodon grandifloras polysaccharides inhibit mitophagy injury induced by Cr (VI) in DF-1 cells

This study aimed to investigate the role of Platycodon grandiflorus polysaccharide (PGPS) in chromium (VI)-induced autophagy in a chicken embryo fibroblast cell lines (DF-1 cells). DF-1 cells were exposed to Cr (VI), PGPS_t, and Cr (VI) + PGPS_t, and their effects on cell viability, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and autophagy-related proteins were examined. The results showed that the cell viability was reduced after Cr (VI) treatment, and 3-MA, CsA or PGPS_t suppressed this decrease. Cr (VI) treatment increased the ROS levels and decreased the MMP, thereby enhancing the expression of mitochondrial autophagy marker proteins (PINK1, Parkin, and LC3-II), inhibiting mitophagy autophagy protein TOMM20 expression, and promoting the degradation of autophagy-related marker p62. These changes led to exceeding mitochondrial autophagy and cell trauma and could be mitigated by PGPS_t. Overall, our research showed that Cr (VI) can induce exceeding mitochondrial autophagy in DF-1 cells, whereas PGPS_t can improve Cr (VI)-induced mitochondrial autophagy by inhibiting ROS and restoring MMP.

Extraction, purification, and determination of the gastroprotective activity of glucomannan from Bletilla striata

In this study, a water-soluble polysaccharide (BSP) was extracted and purified from pseudobulb of Bletilla striata. The preliminary structure and gastroprotective activity of BSP were analyzed. Results indicate that BSP is a glucomannan with a molar ratio of 7.45:2.55 (Man:Glc), and its molecular weight is approximately 1.7 × 10⁵ Da. BSP displayed outstanding protective action against ethanol-induced GES-1 cell injury in vitro, as well as, excellent gastroprotective activity in vivo. Especially, a high-dose of BSP (100 mg/kg) could reduce the ulcer index of the gastric mucosa and increase the percentage of ulcer inhibition, which possibly caused by enhancing the antioxidant capacity and inhibiting the apoptotic pathway in gastric tissue. Interestingly, BSP exhibited a comparative gastroprotective activity to that of positive control (omeprazole). In summary, our results indicated that BSP could be considered as a potential supplement for the prevention of gastric injury.

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.

Cadmium regulates von Willebrand factor and occludin expression in glomerular endothelial cells of mice in a TNF-α-dependent manner

Background: Cadmium (Cd) is an environmental pollutant that leads to nephrotoxicity. However, the mechanisms of Cd-induced glomerular injury have not been fully clarified. Von Willebrand factor (vWF) and occludin are important endothelial cell markers in renal vasculature. In this study, the effects of Cd on the vWF and occludin expression in mouse glomeruli was investigated.

Objectives: The goal of this study was to analyze the expression of von Willebrand factor and occludin in glomerular endothelial cells of tumor necrosis factor-α^−/− (TNF-α^−/−) mice after treatment with Cd.

Material and methods: C57BL6/J wild-type (WT) mice and TNF-α^−/− mice (n = 6) were treated with Cd, and the kidney tissues were collected. The expression of von Willebrand factor and occludin was detected by using quantitative real-time PCR, immunofluorescence, and immunohistochemistry. In vitro, Human umbilical vascular endothelial cells (HUVECs) were used to examine the regulatory role of TNF-α on expression of von Willebrand factor and occludin.

Results: We found that Cd significantly increases mRNA and protein expressions of von Willebrand factor and occludin in TNF-α^−/− mice, but not in WT mice. In vitro, Cd significantly increased mRNA and protein expression of von Willebrand factor and occludin in HUVECs with TNF-α small interfering RNA (siRNA) transfection.

Conclusions: These results suggest that TNF-α acts to balance homeostasis of glomerular endothelium after Cd treatments.

Ex vivo detection of cadmium-induced renal damage by using confocal Raman spectroscopy

Cadmium (Cd) is a toxic heavy metal which is harmful to environment and organisms. The reabsorption of Cd in kidney leads it to be the main damaged organ in animals under the Cd exposure. In this work, we applied confocal Raman spectroscopy to map the pathological changes in situ in normal and Cd-exposed mice kidney. The renal tissue from Cd-exposed group displayed a remarkable decreasing in the intensity of typical peaks related to mitochondria, DNA, proteins and lipids. On the contrary, the peaks of collagen in Cd-exposed group elevated significantly. The components in each tissue were identified and distinguished by principal component analysis. Furthermore, all the biological investigations in this study were consistent with the Raman spectrum detection, which revealed the progression and degree of lesion induced by Cd. The confocal Raman spectroscopy provides a new perspective for in situ monitoring of substances changes in tissues, which exhibits more comprehensive understanding of the pathogenic mechanisms of heavy metals in molecular toxicology.

Cyanidin-3-O-glucoside protects against cadmium-induced dysfunction of sex hormone secretion via the regulation of hypothalamus-pituitary-gonadal axis in male pubertal mice

Cadmium (Cd) has been generally recognized as an endocrine-disrupting chemical for its toxic effects on the hypothalamus-pituitary-gonadal (HPG) axis accompanied by dysfunction in sex hormone secretion. Particularly, exposure to Cd during puberty versus post-puberty exhibits differing age-dependent effects that require further examination. This study sought to determine if cyanidin-3-O-glucoside (C3G), a typical anthocyanin with neuroprotective bioactivity, could protect against Cd-induced sex hormone-disorder in Pubertal male mice. C3G treatment reversed the disruption of hormone levels and increased Gnrh1 gene expression in the hypothalamus. In addition, the levels of gonadotropins, including luteinizing hormone (LH) and follicle stimulating hormone (FSH), were reversed by C3G. Interestingly, C3G improved the expression of LH and FSH receptor in the testis in mice exposed to Cd. Furthermore, C3G activated the signaling pathway related to the synthesis of testosterone processing. In conclusion, C3G protected against Cd-induced dysfunction of sex hormone secretion through the regulation of the HPG axis in male mice during puberty. The results of this study suggest that consumption of anthocyanins can be protective against metal-induced male reproductive dysfunction.

Royal jelly attenuates cadmium-induced nephrotoxicity in male mice

Cadmium exposure induces nephrotoxicity by mediating oxidative stress, inflammation, and apoptosis. The purpose of this study was to examine the protective effect of royal jelly on Cd-induced nephrotoxicity. Adult male mice were distributed randomly into 4 clusters: untreated, royal jelly-treated (85 mg/kg, oral), CdCl₂-treated (6.5 mg/kg, intraperitoneal), and pretreated with royal jelly (85 mg/kg) 2 h before CdCl₂ injection (6.5 mg/kg, intraperitoneal) for seven consecutive days. Cd concentration in the renal tissue and absolute kidney weight of the Cd-treated mice were significantly higher than those of control group. The levels of kidney function markers, kidney injury molecules-1 (KIM-1), metallothionein, lipid peroxidation, nitric oxide, tumor necrosis factor-α, interleukin-1β, and the apoptosis regulators Bax and caspases-3 also increased significantly in the renal tissue of Cd-treated mice, whereas the levels of glutathione, antioxidant enzyme activities, and the apoptosis inhibitor Bcl-2 were significantly reduced in the renal tissue of Cd-treated group. Histopathological studies showed vacuolation and congested glomeruli in the kidney tissue of Cd-treated mice. However, all aforementioned Cd-induced changes were attenuated by pretreatment with royal jelly. We therefore concluded that royal jelly attenuated Cd-induced nephrotoxicity and it is suggested that this nephroprotective effect could be linked to its ability to promote the nuclear factor erythroid 2–related factor 2 (Nrf2)/antioxidant responsive element (ARE) pathway.

Protective effects of a Lachnum polysaccharide against liver and kidney injury induced by lead exposure in mice

This study was designed to investigate the liver and kidney protective efficacy of a Lachnum polysaccharide (LEP) against Pb-induced toxicity in mice. The results showed that LEP decreased the Pb-induced bodyweight loss and organ index. Moreover, biochemical analysis showed that treatment of LEP could improve antioxidant status (CAT, GSH-Px and MDA) and the injury of tissues (liver and kidney). In addition, the histopathological observations indicated that LEP could attenuate liver and kidney cell injury induced by Pb. For further studies, key proteins involved in hepatic and kidney apoptosis, including cleaved caspase-3, Bax, Bcl-2, TGF-β1 and α-SMA, were quantified. The present findings demonstrated that LEP is strongly effective in protecting against the liver and kidney injury induced by Pb. We hope this research can offer a theoretical base for development of polysaccharide based on nutraceutical food in future.