Protective effect of Smilax glabra extract against lead-induced oxidative stress in rats

Concomitant Exposure to Lower Doses of Arsenic, Lead, and Manganese Induces Greater Synergistic Neurotoxicity Than Individual Metals in Mice

People in Bangladesh are often exposed to low to high levels of multiple metals due to contaminated groundwater with various heavy metals such as arsenic (As), lead (Pb), and manganese (Mn). However, the effects of concomitant exposure of these three metals on neurobehavioral changes are yet to be studied. Therefore, this study was intended to assess the neurotoxic effect of As, Pb, and Mn in a mouse model. Elevated plus maze (EPM) and Morris water maze (MWM) tests were conducted to evaluate anxiety, learning, and spatial memory impairment, respectively. The mice exposed to a combination of metals spent least time exploring the open arms and had longer latencies to find the hidden platform than the control and individual metal exposure groups in EPM and MWM tests. Moreover, concomitant multi-metal exposure remarkably decreased the activities of cholinergic and antioxidant enzymes, brain-derived neurotropic factor (BDNF), and nuclear factor erythroid 2-related factor 2 (Nrf2) levels and significantly increased interleukin-6 (IL-6) level in the brain tissue compared to the control and individual metal-exposed mice. Among the mice treated with a single metal, the As-treated mice showed the highest toxic effects than Pb- or Mn-treated mice. Taken together, the present study demonstrated that exposure to a mixture of As, Pb, and Mn, even at lower doses than individual metals, significantly augmented anxiety-like behavior and impaired learning and spatial memory compared to exposure to individual metals, which was associated with the changes of BDNF, Nrf2, IL-6 levels, and related enzyme activities in the brain.

Investigation of the molecular mechanism of Smilax glabra Roxb. in treating hypertension based on proteomics and bioinformatics

Background

Smilax glabra Roxb. (named tufuling in Chinese, SGR) has both medicinal and edible value. SGR has obvious pharmacological activity, especially in anti-inflammation and treating immune system diseases. This study investigated differential protein expression and its relationship with immune infiltration in hypertension treated with SGR using proteomics and bioinformatics.

Methods

N-Nitro L-arginine methyl ester (L-NAME) was used to replicate the hypertension model, with SGR administered by gavage for 4 weeks, and the systolic and diastolic blood pressure in each group of rats was measured using the tail-cuff method every 7 days. Furthermore, enzyme-linked immunosorbent assay (ELISA) was used to determine the serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) expressions in each group, followed by the detection of protein expression in rat liver samples using the tandem mass tag (TMT) technique. Additionally, hub targets were output using Cytoscape 3.9.1 software, and ALDH2 expression in the liver and serum in each group of rats was detected by ELISA. Moreover, R4.3.0 software was used to evaluate the relationship between acetaldehyde dehydrogenase 2 (ALDH2) and immune cells, and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was performed to identify the components of SGR. Furthermore, the association between components of SGR and ALDH2 was analyzed with molecular docking and LigPlot1.4.5 software.

Results

Compared with the model group (L-NAME), SGR at high and medium doses reduced systolic and diastolic blood pressure while reducing TC, TG, and LDL-C levels and increasing HDL-C levels in hypertensive rats (p < 0.05). Moreover, 92 differentially expressed proteins (DEPs) were identified using TMT. These DEPs participated in peroxisome functioning, fatty acid degradation, and other signaling pathways, with ALDH2 being the core target and correlated with various immune cells. In addition, 18 components were determined in SGR, with 8 compounds binding to ALDH2. Molecular docking was performed to confirm that SGR played a role in hypertension based on the combined action of multiple components.

Conclusion

In conclusion, SGR has an antihypertensive effect on L-NAME-induced hypertension, with ALDH2 as its hub target. SGR may regulate neutrophil, regulatory T cell, and other cells' infiltration by targeting ALDH2, thereby contributing to the treatment of hypertension.

Protective Role of Myricetin and Fisetin Against Nephrotoxicity Caused by Lead Acetate Exposure through Up-regulation of Nrf2/HO-1 Signalling Pathway

The effect of various flavonoids against oxidative stress and inflammation caused by lead exposure has been investigated. However, the protective effects of myricetin (MYC) and fisetin (FST), which are known to have potent antioxidant properties, against nephrotoxicity caused by exposure to lead acetate (LA), the water-soluble form of lead, have not been investigated. Our study investigated the protective role of these flavonoids against LA intoxication-induced nephrotoxicity. In our study, 42 male rats were used. The rats were randomly selected and divided into 6 groups. These groups were: control, LA (100 g/kg), LA + MYC (100 mg/kg), LA + MYC (200 mg/kg), LA + FST (100 mg/kg) and LA + FST (200 mg/kg). All chemicals were administered daily by gavage for 28 days. According to the experimental protocol, the animals were sacrificed and their kidney tissues were isolated. Serum biochemical parameters, histological examinations, levels of several trace elements, oxidative stress and inflammatory parameters at both biochemical and molecular levels in kidney tissues were examined. After LA administration, tissue lead levels increased and zinc levels decreased. This situation was reversed by MYC and FST treatment. Oxidative stress and inflammatory response were increased in the kidney tissue of LA-treated rats and renal function was impaired. It was observed that both doses of MYC and high dose of FST could prevent nephrotoxicity. Oral administration of both doses of MYC and high dose FST ameliorated the changes in biochemical, oxidative and inflammatory parameters. Restoration of normal renal tissue architecture was also demonstrated by histological studies. MYC and FST were found to have promising biological activity against LA-induced nephrotoxicity, acting by attenuating inflammation and oxidative stress and improving antioxidant status.

Pharmacological effect of Argyrolobium roseum (Camb.) Jaub & Spach extracts against lead-induced toxicity in rats

Argyrolobium roseum (Camb.) Jaub & Spach (Papilionaceae) is a medicinal plant, cultivated in northern areas of Pakistan. The consumption of trace minerals (lead) is very toxic to the vital organs of the body, therefore the overcome of these minerals is very necessary. In this regard, this study aimed to assess the potential pharmacological effect of aqueous and ethanolic extract of Argyrolobium roseum (Camb.) Jaub & Spach against pb-induced oxidative stress, histological changes in Pb-induced rats' liver and kidney, and anti-inflammatory effect. The metal concentrations in liver and kidney homogenates were measured through atomic absorption spectrophotometer. The antioxidant activity was measured through DPPH and FRAP assay. Pb concentrations were significantly higher in liver and kidney homogenates after injection of Pb acetate was given intraperitoneally (45.2 ± 6.8 and 58.8 ± 7.9, respectively; p < .0001). The level of Pb in liver and kidney homogenates was significantly reduced by aqueous and ethanolic extracts of Argyrolobium roseum (Camb.) Jaub & Spach. The Pb + Aq-600 mg/kg-treated rats exhibited a protective effect on hepatocytes cells against Pb-induced liver injury and restored the cells of the kidney. Pb + Aq-600 mg/kg showed higher antioxidant activity as compared to other treated groups. The highest decreased MDA level was found in liver and kidney homogenate of Pb + Aq-600 mg/kg rats (11.2 ± 1.51 nmol/mg; p < .001) and GSH and CAT levels tended to normal after treatment of Pb + Aq-600 mg/kg in rats. The ALAD, ALT, AST, and ALP level were enhanced and tended to be normal after the Aq-400 and Aq-600 mg/kg treatment in Pb-exposed rats. The result showed that 600 mg/kg Aq + Pb exhibited significant (p < .001) anti-inflammatory activity. The findings of this study concluded that treatment of the aqueous extract of Argyrolobium roseum (Camb.) Jaub & Spach reduces the renal and hepatic damage in Pb-induced rats and it also decreases oxidative stress via improving antioxidant components.

Impact of plant extracts on hepatic redox metabolism upon lead exposure: a systematic review of preclinical in vivo evidence

The liver is a central target organ of heavy metals toxicity, and secondary metabolites of several plant species are suggested to attenuate lead (Pb)-induced hepatotoxicity through antioxidant and anti-inflammatory mechanisms. We used a systematic review framework to map the impact of plant extracts and bioactive secondary metabolites on immunological markers and liver redox metabolism in preclinical models of Pb exposure. This is a systematic review performed according to PRISMA guidelines. The structured research of publications was done through PubMed, Scopus, Web of Science, and Embase databases, selecting and analyzing 41 original studies included via the eligibility criteria. Evidence indicates that Pb-exposure increases reactive oxygen/nitrogen species (ROS/RNS) production by δ-aminolevulinic acid auto-oxidation, xanthine dehydrogenase, and xanthine oxidase upregulation. Pb exposure also inhibits antioxidant enzymes, potentiating ROS/NOS levels and reactive cell damage. Plant extracts rich in flavonoids, tannins, alkaloids, anthocyanins, and vitamins exerted hepatoprotective effects by chelating and decreasing Pb bioaccumulation. In addition, plant extracts reinforce exogenous and endogenous antioxidant defenses, attenuating liver oxidative stress and cell death. The lack of blinded evaluators and randomized experimental groups were the main sources of bias identified, which need to be controlled in toxicological studies aimed at identifying natural products applied to the prevention or treatment of Pb poisoning.

Ginkgo biloba supplement abates lead-induced endothelial and testicular dysfunction in Wistar rats via up-regulation of Bcl-2 protein expression, pituitary-testicular hormones and down-regulation of oxido-inflammatory reactions

BACKGROUND

Apoptotic and oxido-inflammatory pathways have been found to be up-regulated in lead acetate poisoning which has been associated to endothelial and testicular dysfunctions. It is yet uncertain, nevertheless, if treatment with Ginkgo biloba supplements (GBS), a flavonoid-rich natural product can lessen the adverse effects of lead on endothelial and testicular functions. This study investigated the impact of Ginkgo biloba supplementation on lead-induced endothelial and testicular dysfunctions.

METHODS

The animals were treated with GBS (50 mg/kg and 100 mg/kg orally) for 14 days following oral exposure to lead acetate (25 mg/kg) for 14 days. After euthanasia, blood samples, epididymal sperm, testes, and aorta were collected. The quantities of the hormones (testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH), as well as the anti-apoptotic, oxidative, nitrergic, inflammatory markers, were then determined using immunohistochemistry, ELISA, and conventional biochemical methods.

RESULTS

GBS reduced lead-induced oxidative stress by increasing the levels of the antioxidant enzymes catalase (CAT), glutathione (GSH), and superoxide dismutase (SOD), while lowering malondialdehyde (MDA) in endothelium and testicular cells. Normal testicular weight was restored by GBS which also decreased endothelial endothelin-I and increased nitrite levels. TNF-α and IL-6 were decreased while Bcl-2 protein expression was enhanced. Lead-induced alterations in reproductive hormones (FSH, LH, and testosterone) were also restored to normal.

CONCLUSION

According to our result, using Ginkgo biloba supplement prevented lead from causing endothelial and testicular dysfunction by raising pituitary-testicular hormone levels, boosting Bcl-2 protein expression and lowering oxidative and inflammatory stress in the endothelium and testes.

Clerodendrum viscosum leaves attenuate lead-induced neurotoxicity through upregulation of BDNF-Akt-Nrf2 pathway in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Clerodendrum viscosum is an important medicinal plant in Ayurveda in Bangladesh and its leaves are used as a remedy for various diseases such as anti-inflammatory, antibacterial, hyperglycemic, hepatoprotective effects.

AIM OF THE STUDY

The present study aimed to evaluate the protective effect of aqueous extract of C. viscosum leaves against Pb-induced neurobehavioral and biochemical changes in mice.

MATERIALS AND METHODS

Swiss albino mice were divided as a) control, b) lead treated (Pb) and c) C. viscosum leaves (Cle) d) Pb plus Cle groups. Pb-acetate (10 mg/kg body weight) was given to Pb and Pb + Cle groups mice, and water extract of leaves (50 mg/kg body weight) was provided as supplementation to Cle and Pb + Cle groups mice for 30 days. Elevated plus maze and Morris water maze tests were used for evaluating anxiety, spatial memory and learning, respectively. Status of cholinesterase, SOD, GSH enzyme activity and neurotoxicity markers such BDNF and Nrf2 levels were analyzed in the brain tissue of experimental mice.

RESULTS

Poorer learning, inferior spatial memory, and increased anxiety-like behavior in Pb-exposure mice were noted when compared to control mice in Morris water maze and elevated plus maze test, respectively. In addition, expression of BDNF and Nrf2, cholinesterase activity along with antioxidant activity were significantly reduced compared to control group (p < 0.01). Interestingly, C. viscosum leaves' aqueous extract supplementation in Pb-exposed mice provide a significant improved neurochemical and antioxidant properties through the augmentation of activity of cholinergic enzymes, and upregulation of BDNF and Nrf2 levels in the brain tissue compared to Pb-exposed mice.

CONCLUSIONS

This study suggested that C. viscosum leaves restore the cognitive dysfunction and reduce anxiety-like behavior through upregulation of BDNF mediated Akt-Nrf2 pathway in Pb-exposure mice.

Disulfiram-Mitigating Unintended Effects

Lyme disease caused by infection with a multitude of vector-borne organisms can sometimes be successfully treated in its very early stages. However, if diagnosis is delayed, this infection can become disseminated and, like another spirochetal infection syphilis, can affect multiple organ systems in the body, causing a wide variety of life-altering symptoms. Conventional antibiotic therapy may not be effective in eradicating the symptoms of the disease we know as Lyme disease. The recent literature has suggested that disulfiram (DSM) may be a potent drug in the armamentarium of physicians who treat chronic Lyme disease. The use of disulfiram in the treatment of Lyme disease started with a researcher who determined that DSM is bactericidal to spirochete. Encouraged by published case reports of apparent recovery from chronic Lyme disease, having prescribed DSM ourselves in the past for alcoholics who had a desire to stop drinking and prescribing it now for patients with chronic Lyme disease, we observed both predictable and potentially avoidable side effects not necessarily related to the ingestion of alcohol. We reviewed the published literature in PubMed and Google Scholar, using the following key words: Lyme Disease; Borrelia burgdorferi treatment; and disulfiram toxicity. This paper outlines the results of that research to help avoid some of the pitfalls inherent in this novel use of an old and established medication in the practice of clinical medicine.

Protective Effect of 3-Benzoyl-7-Hydroxy Coumarin on Lipid Peroxidation and Minerals on Rat Liver Tissues Induced Oxidative Stress with Lead Acetate

Lead is a toxic substance and damages human metabolism. Coumarin-derived substances have many effects such as antioxidant, anticancer, and antibacterial ones. In this study, the effects of 3-benzoyl-7-hydroxy coumarin on rat liver tissues under oxidative stress with lead acetate were investigated. In the study, rats were divided into 4 groups. Control group (K), Coumarin group (KUM), Lead acetate group (P) and Coumarin+Lead acetate group (KUMP) groups were formed. Malondialdehyde (MDA), lead (Pb), iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu) levels were determined in the liver tissues of the rats. MDA level of P group increased compared to the other groups. A decrease was observed in the KUMP group compared to the P group MDA level. While the Pb and Fe levels of the P group increased compared to the K group, the Pb and Fe levels of the KUMP group decreased compared to the P group. As a result, it is concluded that the 3-benzoyl-7-hydroxy coumarin molecule protects the high lipid peroxidation, lead, and iron metabolism caused by lead acetate in the liver.

Up-regulation of B-cell lymphoma factor-2 expression, inhibition of oxidative stress and down-regulation of pro-inflammatory cytokines are involved in the protective effect of cabbage (Brassica oleracea) juice in lead-induced endothelial dysfunction in rats

BACKGROUND

Oxido-inflammatory stress and dysregulation of nitric oxide (NO) system has been implicated in lead toxicity. Cabbage is an antioxidant-rich household vegetable with plethora of therapeutic potentials. The present study investigated the anti-oxido-inflammatory activity of cabbage in lead-induced endothelial dysfunction.

METHODS

Twenty (20) male Wistar rats were selected into four groups (n = 5) and treated with distilled water (1 mL/100 g b.wt), lead acetate (25 mg/kg b.wt), cabbage juice (1 mL/100 g b.wt) and lead acetate (25 mg/kg b.wt) plus cabbage juice (1 mL/100 g b.wt) respectively. Treatment was done orally for 28 days, thereafter, oxidative stress (SOD, CAT, GSH, and MDA), inflammatory (TNF-α and IL-6) and apoptotic (Bcl-2) markers were assayed using standard biochemical assays as well as histoarchitectural study of the endothelium.

RESULTS

The results showed that they were significant increase in MDA, ET-1, TNF-α and IL-6 while SOD, GSH, CAT, NO and Bcl-2 protein expression were decreased in Lead exposed animals. Endothelial histoarchitecture was also altered. Following Cabbage juice treatment, MDA, ET-I, TNF-α and IL-6 were down-regulated while SOD, GSH, CAT, NO and Bcl-2 protein expression were up-regulated. Histoarchitecture was significantly recovered.

CONCLUSION

The study suggests that cabbage juice could mitigates Lead-induced endothelial dysfunction by modulating oxido-inflammatory and anti-apoptotic mediators.

DATA AVAILABILITY

All data are available upon request.

Tentative Identification of Phytochemicals from Smilax glabra and Smilax corbularia Extracts by LC-QTOF/MS and Their Bioactive Potential

The Smilacaceae family has been used as a food source and herbal medicine for a long time. This study aims to identify the phytochemicals extracted from Smilax glabra and Smilax corbularia by using LC-QTOF/MS analysis and determine their bioactive potential. Compounds were identified from S. glabra and S. corbularia extracts by LC–QTOF-MS and it was found that longistylin A and CAY10435 have higher degrees of matching compounds (99.66% and 99.87%). Smilax glabra showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 71.94 ± 1.46% and 59.84 ± 4.80%, respectively, and FRAP at 730.69 ± 33.62 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.017 ± 0.001, 0.015 ± 0.001, and 0.016 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents were 0.043 ± 0.002, 0.033 ± 0.002, and 0.006 ± 0.003 mg QE/g, respectively. The anti-inflammatory capacity showed 97.26% protection and 2.74% hemolysis. The antimicrobial activity can inhibit Gram-positive bacteria with a minimum inhibitory concentration (MIC) of 62.5 mg/mL and a minimum bactericidal concentration (MBC) of 500 mg/mL. Smilax corbularia showed antioxidant capacity, i.e., DPPH and ABTS at percentage inhibitions of 72.24 ± 0.64% and 39.87 ± 2.37%, respectively, and FRAP at 208.33 ± 50.80 mg AAE/100 g sample. The total phenolic compound contents of the ethanol, methanol, and water extracts were 0.006 ± 0.000, 0.007 ± 0.002, and 0.002 ± 0.001 mg GAE/g, respectively, while the total flavonoid contents of the ethanol and methanol extracts were 0.012 ± 0.001 and 0.008 ± 0.000 mg QE/g, respectively. The anti-inflammatory capacity showed 96.64% protection and 3.36% hemolysis. The antimicrobial activity of the extracts can inhibit Gram-positive bacteria with a MIC of 31.25 mg/mL and MBC of 125 mg/mL for the ethanol extract and a MIC of 125 mg/mL and MBC of 62.5 mg/mL for the methanol extract. In conclusion, Smilax glabra and Smilax corbularia were found to contain several phytochemicals that can be used for further study. Both Smilax species can also be used as sources of antioxidants and herbal medicines for killing Gram-positive bacteria.

Water toxicants: a comprehension on their health concerns, detection, and remediation

Water is an essential moiety for the human use since a long time. Availability of good-quality water is very essential, as it is used in almost all the industrial, agricultural, and household activities. However, several factors such as increased urbanization and industrialization, extensive use of chemicals, natural weathering of rocks, and human ignorance led to incorporation of enormous toxicants into the water. The water toxicants are broadly classified as inorganic, organic, and radiological toxicants. Inorganic toxicants include heavy metals (As, Cr, Cd, Hg, Ni, Pb) and metalloids, ammonia, nitrate, and fluoride. Uranium is included in radiological toxicants which also causes chemical toxicity. Organic pollutants include polycyclic aromatic hydrocarbons, polychlorinated biphenyls, phenolic compounds, phthalate esters, pesticides, pharmaceutical and personal care products, perchlorates, and flame retardants. These toxicants are harmful for the ecosystem as well as for the human beings causing different types of health complications like lung cancer, nasal cancer, gingivitis, severe vomiting and abdominal pain, hormonal imbalance, skeletal damage, neurotoxicity like Alzheimer and Parkinson disease, renal toxicity, nephrotoxicity, etc. The USEPA and WHO specified the permissible concentration of these pollutants in the drinking water. Determination techniques having high sensitivity, low cost, rapid onsite, and real-time detection of traces of water pollutants are discussed. This review also covers in depth about the remediation techniques, for the control of water toxicants, such as chelation of the heavy metals, intoxication of pollutants using various plants, adsorption of toxicants using different sorbent medias, and photocatalytic breakdown of persistent organic pollutants (POPs).

Modulatory efficacy of Punica granatum L. powder ethanol extract (PLEE) on lead acetate-induced hepatic and renal toxicity

Background

Pomegranate powder derived from pomegranate fruit contains phytochemicals chief of which is ellagitannins. Owing to their high antioxidative capabilities we investigated its efficacy against lead acetate induced hepatic and renal toxicity.

Methods

Pomegranate powder (500 g) was procured and soaked in 1 Litre of ethanol for three days, its filtrate was concentrated and freeze dried to form Punica granatum L. ethanol extract (PLEE). Thirty (30) male albino Wistar rats with average weight between 140 ± 20 g were used for this study. They were equally shared into 6 groups with 5 animals each; A: Control; B: Lead acetate only C: Lead acetate + PLEE (1); D: Lead acetate + PLEE (2); E: PLEE (1) and F: PLEE (2). Serum, liver and kidney samples were obtained for biochemical assays. The integrity of liver and kidney tissues were also accessed.

Results

Lead administration resulted in marked elevations in liver transaminases in serum and liver as well as a significant increase in kidney function markers in the serum and kidney (p < 0.05). There was also a significant decline in average body weight, antioxidant markers in the liver and kidney of Wistar rats while there was a significant increase in lipid peroxidation levels in both liver and kidney. However, administration of PLEE at different doses significantly modulated these changes.

Conclusion

Lead acetate administration led to hepatic and renal toxicity as evident by alterations in liver and kidney function markers, antioxidant status and tissue integrity. However, PLEE can combat these toxicities.

Protective Effects of Chrysin Against Oxidative Stress and Inflammation Induced by Lead Acetate in Rat Kidneys: a Biochemical and Histopathological Approach

In this study, the protective effects of chrysin (CR) on lead acetate (PbAc)-induced renal toxicity in Sprague-Dawley rats were investigated with biochemical, histopathological, and immunohistochemical methods. In the study, rats were given orally at 30 mg/kg/body weight (BW) PbAc after CR of 25 and 50 mg/kg/BW was administered to them orally (a total of 7 administrations for 7 days). The results showed that CR reduced urea and creatinine levels by alleviating PbAc-induced kidney damage. It was determined that CR decreases PbAc-induced lipid peroxidation due to its antioxidant properties and increases catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) activities, and glutathione (GSH) levels. It was also detected that CR protects DNA from the toxic effects of PbAc and reduces 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels. Biochemical and immunohistochemical findings demonstrated that CR had anti-inflammatory and antiapoptotic effects and reduced nuclear factor kappa-B (NF-κB), interleukin-33 (IL-33), prostaglandin-E2 (PGE-2), tumor necrosis factor-α (TNF-α), p53 levels, and the activities of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), which were increased with PbAc administration. Moreover, CR was found to increase the levels of aquaporin-1 (AQP-1) and nephrine in PbAc-induced kidney tissue. CR decreased the contents of lead (Pb), zinc (Zn), iron (Fe), sodium (Na), and copper (Cu) and increased those of potassium (K) calcium (Ca) in renal tissue. These results indicated that CR considerably alleviates kidney toxicity caused by PbAc.

Chrysin protects against testicular toxicity caused by lead acetate in rats with its antioxidant, anti-inflammatory, and antiapoptotic properties

In the present study, the protective effects of chrysin (CHR) against testicular damage caused by lead acetate (PbAc) were examined. In this way, 30 min after rats were given 25 and 50 mg/kg/b.w CHR orally for seven consecutive days, 30 mg/kg/b.w PbAc was administered orally. In biochemical analysis of testicular tissue, it was found that PbAc-reduced antioxidant parameters [glutathione peroxidase (GPx), glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT)], while it increased lipid peroxidation, inflammatory markers [nuclear factor kappa-B (NF-κB), cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE-2), and inducible nitric oxide synthase (iNOS)], and 8-hydroxy-2'-deoxyguanosine (8-OHdG). In the immunohistochemical examination, it was determined that PbAc increased the expression of tumor necrosis factor-α (TNF-α) and caspase-3. Accordingly, PbAc was found to cause a decrease in sperm motility and an increase in the percentage of dead sperm. However, it has been observed that CHR relieves oxidative stress due to its antioxidant properties, thus protecting against inflammation and apoptosis. It also allowed the CHR sperm parameters to return to control group levels. The results revealed that CHR could be a natural substance to be used in Pb-induced testicular toxicity. PRACTICAL APPLICATIONS: Lead (Pb) is an important environmental contaminant heavy metal. Pb is believed to reduce fertility in men. Oxidative stress plays a significant role in the damage caused by Pb to testicular tissue. CHR is an antioxidant substance that occurs naturally in various plants and has various pharmacological properties. In the present study, it was investigated whether CHR has a protective effect against testicular toxicity induced by PbAc. The results revealed that in rats, CHR protects the testicular tissue from PbAc toxicity by showing antioxidant, anti-inflammatory and anti-apoptotic effects, thus bringing sperm parameters closer to normal.

Metal toxicity and natural antidotes: prevention is better than cure

Toxicity due to heavy metals (HM), specifically mercury (Hg), arsenic (As), lead (Pb), and cadmium (Cd) remains a challenge to scientists till date. This review gives insights into natural antidotes for the management and prevention of HM toxicity. Various databases such as PubMed, Embase, and Science Direct were searched for available facts on natural antidotes and their commercial products against HM toxicity till date. Toxicity owing to such metals needs prevention rather than therapy. Natural antidotes, fruits and vegetables, rich in antioxidant are the answers to such toxicities. Synthetic chelators impart a major drawback of removing essential metals required for normal body function, along with the toxic one. Natural antioxidants are bestowed with scavenging and chelation properties and can be alternative for synthetic chelating agents. Natural compounds are abundantly available, economic, and have minimal side effects when compared with classical chelators. Prevention is better than cure and thus adding plentiful vegetables and fruits to our diet can combat HM toxicity-related illness. Graphical abstract.

Protective Effects of Smilax glabra Roxb. Against Lead-Induced Renal Oxidative Stress, Inflammation and Apoptosis in Weaning Rats and HEK-293 Cells

Lead (Pb) is an important environmental pollutant. Oxidative stress and the inflammatory response have been postulated as mechanisms involved in lead-induced renal damage. Smilax glabra Roxb. has been used for treatment of heavy-metal poisoning in China for 500 years. We investigated S. glabra flavonoids extract (SGF) could attenuate lead acetate-induced nephrotoxicity in weaning rats and human embryonic kidney (HEK)-293 cells, and investigated the possible mechanisms. Compared with Pb exposed group of weaning rats, SGF could significantly promote lead excretion in the blood and kidney, and increase the content of the renal-function indicators blood urea nitrogen, serum uric acid, and serum creatinine. SGF could improve the glomerular filtration rate (GFR) and histologic changes in the kidneys of weaning rats exposed to Pb. SGF could also reduce lead-induced cytotoxicity, improve DNA damage-induced apoptosis and cleaved caspase-3-mediated apoptosis in HEK-293 cells stimulated with Pb. SGF significantly increased the activity of the antioxidant enzymes superoxide dismutase, glutathione peroxidase and catalase, and decreased excessive release of reactive oxygen species (ROS) and malondialdehyde in the kidneys of the weaning rats and in HEK-293 cells. The antioxidant mechanism of SGF related to activation of the Kelch-like ECH-associated protein 1/nuclear-factor-E2-related factor 2/hemeoxygenase-1(Keap1/Nrf2/HO-1) pathway. SGF could inhibit secretion of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α induced by Pb in vivo and in vitro. The anti-inflammatory mechanism of SGF related to inhibition of ROS and pro-inflammatory cytokines triggered the nuclear factor-kappa B (NF-κB) pathway through blockade of inhibitors of I-κB degradation, phosphorylation of NF-κB p65, and nuclear translocation of p65. Our findings indicate that SGF could be a natural antioxidant and anti-inflammatory agent for treating lead-induced nephrotoxicity.

Discovery of the active compounds of Smilacis Glabrae Rhizoma by utilizing the relationship between the individual differences in blood drug concentration and the pharmacological effect in rats

ETHNOPHARMACOLOGICAL RELEVANCE

This study addresses the rapid discovery of the active compounds (the original constituents and/or metabolites) of a traditional Chinese drug, Smilacis Glabrae Rhizoma (SGR).

AIM OF THE STUDY

The aim of this study was to develop a new method to find out the active compounds of traditional drugs in vivo.

MATERIALS AND METHODS

A method was established to discover and identify the potential active compounds in drug-containing plasma from rats that were orally administered SGR extract, utilizing the relationship between the individual differences in blood drug concentrations in the rats and the resulting differences in pharmacological effect, and the method was denoted as the RID-PE method. For this method, we used high-performance liquid chromatography with a diode array detector combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry (LC-MSⁿ) to identify the compounds (the original constituents and metabolites) and to determine the peak areas of the compounds in drug-containing plasma following SGR treatment. The anti-inflammatory effect of SGR was evaluated using a carrageenan-induced inflammatory rat model. According to the percent inhibition of paw edema in each model rat (14 rats total) orally administered SGR extract, the plasma samples from the rats were sorted and divided into 7 groups. Each group consisted of two plasma samples, and their percent inhibition of paw edema were similar to each other. We performed an LC-MSⁿ analysis on 3 plasma groups, which showed large differences in the inhibition rates, with percent inhibitions of 92.7%, 72.4% and 38.4%. The correlation coefficients (r) between the peak area of each compound and the pharmacological effect (inhibition ratio) of SGR in the three groups were analyzed using SPSS software. When the correlation coefficients of the compounds are greater than 0.8 (0.8 < r ≤1), these compounds are strongly and positively correlated with anti-inflammatory activity, making them potential anti-inflammatory active compounds.

RESULTS

Fifty-eight potential anti-inflammatory compounds (0.8 < r ≤ 1) from SGR were discovered in model rat plasma using the RID-PE method, 47 of which were considered to be new potentially anti-inflammatory compounds. Among these compounds, four original constituents and 5 isomers of potential anti-inflammatory metabolites were validated to have significant anti-inflammatory effects, and they included astilbin, syringic acid, catechin, coumalic acid, resveratrol-3'-O-glucuronide (RG, isomer of M2 or M3), 3'-O-methyl-(+)-epicatechin-4'-O-glucuronide (CA-1, isomer of M16), 4'-O-methyl-(+)-epicatechin-3'-O-glucuronide (CA-2, isomer of M16), 4'-O-methyl-(+)-epicatechin-7-O-glucuronide (CA-3, isomer of M16) and 3'-O-methyl-(+)-epicatechin-7-O-glucuronide (CA-4, isomer of M16). In addition, four isomers (CA-1-CA-4) were reported to have anti-inflammatory effects for the first time, and CA-3 was a new compound.

CONCLUSIONS

The RID-PE method can be used to discover and identify the active constituents and metabolites of SGR systematically and in vivo. Furthermore, these findings enhance our understanding of the metabolism and effective forms of SGR.

Smilax glabra Roxb. Inhibits Collagen Induced Adhesion and Migration of PC3 and LNCaP Prostate Cancer Cells through the Inhibition of Beta 1 Integrin Expression

Smilax glabra Roxb. (SGR) has been used as a traditional medicine for brucellosis and syphilis. In this study, we investigated whether nontoxicological levels of water extract of SGR (WESGR) are effective for suppressing steps in the progression of prostate cancer, such as collagen-mediated migration and adhesion and identified the target molecule responsible for such effects. We found that nontoxicological levels of WESGR did not attenuate PC3 and LNCaP cell adhesion to serum but did significantly do so with collagen. In addition, using the Boyden chamber assay, we found that nontoxicological levels of WESGR did not inhibit the migration of PC3 and LNCaP cells to a serum-coated area but did significantly attenuate migration to a collagen-coated area. Interestingly, the expression of α2β1 integrin, a known receptor of collagen, was not affected by ectopic administration of WESGR. However, WESGR significantly attenuated the expression of β1 integrin, but not α2 integrin when PC3 and LNCaP cells were placed on a collagen-coated plate, resulting in attenuation of focal adherent kinase phosphorylation. Finally, 5-O-caffeoylquinic acid was determined as a functional single component which is responsible for antiprostate cancer effects of WESGR. Taken together, our results suggest a novel molecular mechanism for WESGR-mediated antiprostate cancer effects at particular steps such as with migration and adhesion to collagen, and it could provide the possibility of therapeutic use of WESGR against prostate cancer progression.

Ameliorative and protective effects of fucoidan and sodium alginate against lead-induced oxidative stress in Sprague Dawley rats

The current study was performed to evaluate the possible protective effects of fucoidan (F) and sodium alginate (SA) against lead-induced oxidative damage in vivo, and to identify relevant underlying mechanisms. Health Sprague Dawley (SD) rats were divided into nine groups of ten rats each and treated orally with lead acetate (5 mg/kg, Pb2+) for 4 weeks, then gavaged with DMSA (Meso-2, 3-dimercaptosuccinic acid, 25 mg/kg), F (50, 100, 200 mg/kg) and SA (50, 100, 200 mg/kg) individually after successful modelling. We found that the administration of both F or SA resulted in a beneficial effect by significantly decreasing lead levels (p < 0.05) in the kidneys from 2.85 mg/kg to 0.79 mg/kg and improving antioxidant status (SOD, GSH, and CAT) thereby alleviating lead-induced damage and injury of the liver and kidneys (AST, BUN, and Cr). Both natural extracts exerted dose-dependent effects. Protective effects were further demonstrated by histopathology. Our results demonstrate that the F and SA are effective natural extracts for lead-eliminating, and that they can ameliorate oxidative damage induced by lead toxicity.

Astilbin reduces ROS accumulation and VEGF expression through Nrf2 in psoriasis-like skin disease

Background

Psoriasis is a common and intractable skin disease affecting the physical and mental health of patients. The accumulation of ROS is involved in the pathogenesis of psoriasis and antioxidants are believed to be therapeutic. This study aimed to investigate the therapeutic efficacy of astilbin on ROS accumulation in psoriasis.

Results

The study showed that 50 μg/ml astilbin could inhibit the growth and reduce the accumulation of ROS in HaCaT cells stimulated by IL-17 and TNF-α. Astilbin could elevate the Nrf2 accumulation in the nuclei, eventually leading to the transcriptional activation of various antioxidant proteins and reducing the expression of VEGF.

Conclusions

Our results collectively suggest that astilbin could induce Nrf2 nucleus translocation, which is contribute to reduce the ROS accumulation and VEGF expression, and inhibit the proliferation of HaCaT cells.

Protective effect of Abutilon indicum against lead-induced reproductive toxicity in male Wistar rats

Despite ample literature on the toxic impact of lead on the environment and health, the exact mechanism of pathogenesis/toxicity is not clearly known. Because it is well established that lead induces oxidative stress, it is assumed that exposure to antioxidants may reduce the toxic impact of lead. In this study, we evaluated the impact of coadministration of the methanolic root extract of a plant Abutilon indicum (50, 100, 200 mg kg ^-1 b.wt.) in mitigating the toxic impact of lead on the reproductive system of rats. In brief, Wistar rats were exposed to lead acetate in drinking water with or without coadministration of plant root extract and compared with that of control animals. After 45 days of exposure as outlined above, the animals were killed and the reproductive toxicity was assessed by sperm parameters, hormone and antioxidant enzyme assays, and testis histopathology. Significant reduction in testis weight, sperm count, testosterone levels, and antioxidant enzymes levels such as Superoxide Dismutase, Catalase, and Glutathione peroxidase was seen in lead-treated animals, confirming the toxic impact. The coadministration of A. Indicum (100 and 200 mg kg ^-1 b.wt.) was found to bring the studied parameters close to the levels seen in untreated (control) animals. Our findings are indicative of the protective nature of A. Indicum against lead-induced reproductive toxicity in a dose-dependent manner. However, further characterization of the root extract is required to elucidate the probable mechanism of protection.

Chlorogenic acid relieves lead-induced cognitive impairments and hepato-renal damage via regulating the dysbiosis of the gut microbiota in mice

Lead (Pb), a heavy metal which is widely recognized as an environmental toxicant, is transported from the earth's crust into the human body to a significant extent. To control and reduce the hazard of Pb burdens in the human body, chlorogenic acid (CGA) has been used to antagonize Pb-induced cognitive impairments, and hepatic and renal toxicity in the present study. Seven-week-old male Kunming mice were treated with PbCl2 (1.34 g L-1 in drinking water) and/or CGA (30 mg per kg mouse per day) by gavage administration for 8 weeks. In this study, we evaluated behavior tests, serum biochemical parameters, biomarkers of oxidative stress, and community structure of gut microbiota in mice to explore the potential mechanism of the protective effect. Based on our results, CGA appreciably prevented memory impairment, the release of serum biomarkers, and oxidative stress caused by Pb intake. CGA significantly inhibited Pb-induced increase of cytoplasmic NF-κB, Bax, cytochrome C, and caspase-9 protein expressions. Furthermore, Pb + CGA treatment had a remarkable reversion effect of the gut microbiota composition change induced by Pb, for example increasing the ratio of Helicobacter from 2.95% (Pb) to 11.24% (Pb + CGA) and decreasing the ratio of the Lachnospiraceae_NK4A136_ group from 7.09% (Pb) to 2.68% (Pb + CGA), which suggests that CGA is a superior natural product to eliminate Pb-induced nephrotoxicity and hepatotoxicity.

Natural antidotes and management of metal toxicity

The global burden of heavy metal especially mercury, arsenic, lead, and cadmium toxicities remains a significant public health challenge. Developing nations are particularly at high risk and carry the highest burden of this hazard. Chelation therapy has been the mainstay for treatment of heavy metal poisoning where the chelating agent binds metal ions to form complex ring-like structures called "chelates" to enhance their elimination from the body. Metal chelators have some drawbacks such as redistribution of some heavy metals from other tissues to the brain thereby increasing its neurotoxicity, causing loss of essential metals such as copper and zinc as well as some serious adverse effects, e.g., hepatotoxicity. The use of natural antidotes, which are easily available, affordable, and with little or no side effects compared to the classic metal chelators, is the focus of this review and suggested as cheaper options for developing nations in the treatment of heavy metal poisoning.

Chemical profiles, antioxidant activity and acute toxicity of raw and sulfur-fumigated Smilacis Glabrae Rhizoma

ETHNOPHARMACOLOGICAL RELEVANCE

Smilacis Glabrae Rhizoma (SGR), known as Tu-fu-ling in the China, Japan and Korea, is an herb that has been used for clearing damp and detoxification in traditional Chinese medicine for many years. The post-harvest drying of SGR has traditionally been done by the sun, but sometimes sulfur fumigation is used instead due to its low cost and high efficiency. Recent reports show that sulfur fumigation can change the chemical constitution of herbal medicines and decrease their biology activity.

AIM OF THE STUDY

This study will investigate the changes to the chemical constitution, acute toxicity and antioxidant potential of SGR that occur after sulfur fumigation. To date, no studies have investigated these aspects simultaneously.

MATERIALS AND METHODS

An ultra-performance liquid chromatography fingerprint method was developed for analysing changes to SGR's chemical constitution caused by sulfur fumigation. The chromatography conditions were as follows: all samples were analysed on a Waters Acquity UHPLC HT3 C18 column; the linear gradient elution was conducted with a mobile phase prepared from acetonitrile and water. All calibration curves showed good linear regression (R > 0.9991) within the tested range. The method was validated for precision, accuracy, limit of detection and quantification. Total flavonoids of the raw and sulfur-fumigated samples were also determined by ultraviolet spectrophotometry. The antioxidant properties of the extracts were evaluated using both DPPH and ABTS radical scavenging assays. The acute toxicities of the raw and sulfur-fumigated samples were investigated.

RESULTS

The results demonstrate that the amounts of astilbin, neoastilbin, neoisoastilbin, isoastilbin, resveratrol and total flavonoids were lower in sulfur-fumigated samples than in raw samples. The antioxidant activity of the sulfur-fumigated samples was also significantly lower. Therefore, sulfur fumigation may cause chemical transformation, alter the chemical constitution, and decrease the bioactivity of SGR. Orally-administered doses did not cause mortality or changes in the general behaviour of tested mice. The LD50 was > 5000 mg/kg DW. However, the high-dose S-SGR mice had significant liver damage and high levels of plasma biochemical parameters (ALT, AST, DBIL, TBIL).

CONCLUSIONS

The results of the current study suggest that sulfur fumigation can decrease antioxidant activity in vitro; and that orally-administrated S-SGR is unsafe at doses > 3000 mg/kg dried materia medica. Therefore, sulfur-fumigation processing should be forbidden for SGR until its efficacy and safety has been demonstrated. An alternative method of sulfur fumigation for the post-harvest processing of SGR should also be developed.

The flavonoid-rich fraction from rhizomes of Smilax glabra Roxb. ameliorates renal oxidative stress and inflammation in uric acid nephropathy rats through promoting uric acid excretion

Uric acid metabolic disorder is considered to be the main pathogenesis of uric acid nephropathy (UN). Smilax glabra Roxb. is a traditional Chinese herb which has been used in the treatment of gout, but the mechanism was unclear. In this study, we investigated the protective effects of the flavonoid-rich fraction from rhizomes of Smilax glabra Roxb. (SGF) on uric acid nephropathy rats and its underlying mechanisms of promoting uric acid excretion. Sprague Dawley (SD) rats were induced by high purine diet (yeast pellets + adenine) for 5 weeks. Rats were orally treated with SGF or allopurinol daily. The biochemical parameters and enzymes in different treated rats were determined by commercial kits. Kidney pathology was visualized using optical microscopy and electron microscopy. Renal inflammatory factors were detected by ELISA. Renal fibrosis factors and uric acid transporters were analyzed by real time RT-PCR and western blot. The results showed that SGF significantly improved kidney function. Histopathologic examination revealed that urate-induced renal damage was markedly reversed by SGF. Meanwhile, SGF treatment was also found to significantly inhibit renal oxidative stress. SGF treatment obviously suppressed the inflammatory factors of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and the profibrotic factors of basic fibroblast growth factor (bFGF), transforming growth factor-β₁ (TGF-β₁) expression in UN rats. Moreover, SGF either significantly inhibited uric acid production or promoted uric acid excretion in UN rats. The mechanism of SGF promoting uric acid excretion was related to its increase of ATP-binding cassette transporter G2 (ABCG2), organic anion transporter 1 (OAT1), organic anion transporters 2 (OCT2) and organic cation/carnitine transporters 2 (OCTN2) expression. In conclusion, SGF could ameliorate renal oxidative stress and inflammation in UN rats through promoting uric acid excretion.

Spectroscopic Studies on Dual Role of Natural Flavonoids in Detoxification of Lead Poisoning: Bench-to-Bedside Preclinical Trial

Ubiquitousness in the target organs and associated oxidative stress are the most common manifestations of heavy-metal poisoning in living bodies. While chelation of toxic heavy metals is important as therapeutic strategy, scavenging of increased reactive oxygen species, reactive nitrogen species and free radicals are equally important. Here, we have studied the lead (Pb) chelating efficacy of a model flavonoid morin using steady-state and picosecond-resolved optical spectroscopy. The efficacy of morin in presence of other flavonoid (naringin) and polyphenol (ellagic acid) leading to synergistic combination has also been confirmed from the spectroscopic studies. Our studies further reveal that antioxidant activity (2,2-diphenyl-1-picrylhydrazyl assay) of the Pb-morin complex is sustainable compared to that of Pb-free morin. The metal-morin chelate is also found to be significantly soluble compared to that of morin in aqueous media. Heavy-metal chelation and sustainable antioxidant activity of the soluble chelate complex are found to accelerate the Pb-detoxification in the chemical bench (in vitro). Considering the synergistic effect of flavonoids in Pb-detoxification and their omnipresence in medicinal plants, we have prepared a mixture (SKP17LIV01) of flavonoids and polyphenols of plant origin. The mixture has been characterized using high-resolution liquid chromatography assisted mass spectrometry. The mixture (SKP17LIV01) containing 34 flavonoids and 76 other polyphenols have been used to investigate the Pb detoxification in mouse model. The biochemical and histopathological studies on the mouse model confirm the dual action in preclinical studies.

Protective Effects of Dietary Supplements Containing Probiotics, Micronutrients, and Plant Extracts Against Lead Toxicity in Mice

Lead (Pb) intoxication is a serious food safety issue, and the development of relevant dietary strategies is an area of ongoing research. In this study, two different dietary supplements were designed and evaluated for their effects against Pb toxicity in mice. Dietary supplement A contained grape seed extract, tea polyphenols and Lactobacillus plantarum CCFM8661, and dietary supplement B contained vitamin C, calcium carbonate, zinc acetate, and L. plantarum CCFM8661. The results showed that both dietary supplements could effectively decrease Pb levels, protect aminolevulinic acid dehydratase, superoxide dismutase and catalase activities and recover glutathione, zinc protoporphyrin and malondialdehyde levels in tissues and blood of mice. A step-through passive avoidance task confirmed that the dietary supplements could recover the learning and memory capacities of Pb-exposed mice. The protective effects of both dietary supplements to alleviate oxidative stress and cognitive impairments were superior to the chelator treatment. Administration of the dietary supplements during Pb exposure offered more significant protection than administration after Pb exposure. Animal safety evaluation also indicated that these dietary supplements barely induced side effects in the mice. This study provides evidence that dietary supplements containing probiotics, micronutrients, and plant extracts can be considered a new dietary strategy against Pb toxicity.

Toxicodynamics of Lead, Cadmium, Mercury and Arsenic- induced kidney toxicity and treatment strategy: A mini review

Environmental pollution has become a concerning matter to human beings. Flint water crisis in the USA pointed out that pollution by heavy metal is getting worse day by day, predominantly by Lead, Cadmium, Mercury and Arsenic. Despite of not having any biological role in flora and fauna, they exhibit detrimental effect following exposure (acute or chronic). Even at low dose, they affect brain, kidney and heart. Oxidative stress has been termed as cause and effect in heavy metal-induced kidney toxicity. In treatment strategy, different chelating agent, vitamins and minerals are included, though chelating agents has been showed different fatal drawbacks. Interestingly, plants and plants derived compounds had shown possible effectiveness against heavy metals induced kidney toxicity. This review will provide detail information on toxicodynamics of Pb, Cd, Hg and As, treatment strategy along with the possible beneficiary role of plant derived compound to protect kidney.

Ethnomedicine, Phytochemistry and Pharmacology of Smilax glabra: An Important Traditional Chinese Medicine

Smilax glabra (SG) Roxb., a well-known traditional Chinese medicine, has been extensively used worldwide for its marked pharmacological activities for treating syphilitic poisoned sores, limb hypertonicity, morbid leucorrhea, eczema pruritus, strangury due to heat, carbuncle toxin, and many other human ailments. Approximately 200 chemical compounds have been isolated from SG Roxb., and the major components have been determined to be flavonoids and flavonoid glycosides, phenolic acids, and steroids. Among these active compounds, the effects of astilbin, which is used as a quality control marker to determine the quality of SG Roxb., have been widely investigated. Based on in vivo and in vitro studies, the primary active components of SG Roxb. possess various pharmacological activities, such as cytotoxic, anti-inflammatory and immune-modulatory effects, anti-oxidant, hepatoprotective, antiviral, antibacterial, and cardiovascular system protective activities. However, an extensive study to determine the relationship between the chemical compositions and pharmacological effects of SG Roxb. has not been conducted and is worth of our study. Improving the means of utilizing the effects of SG is crucial. The present paper reviews the ethnopharmacology, phytochemistry, and pharmacology of SG Roxb. and assesses its ethnopharmacological use in order to explore its therapeutic potential for future research.

Preventive use of berberine in inhibition of lead-induced renal injury in rats

The kidney is one of the main organs affected by lead toxicity. We investigated the effects of berberine on lead-induced nephrotoxicity in adult male Wistar rats. Animals received an aqueous solution of lead acetate (500 mg Pb/L in the drinking water) and/or berberine (50 mg/kg, i.g.) for 8 weeks. Lead caused an increase in malondialdehyde (P < 0.001) and total oxidant status (P < 0.01), and a decrease in reduced glutathione (P < 0.001), catalase (P < 0.01), superoxide dismutase (P < 0.001), and total antioxidant capacity (P < 0.05). Berberine prevented the prooxidant and antioxidant imbalance induced by lead (P < 0.001). Berberine corrected the increased relative kidney weight (P < 0.05) and biomarkers of renal function (creatinine (P < 0.001), urea (P < 0.05), uric acid (P < 0.001), albumin (P < 0.01), and total protein (P < 0.05)) in lead group. It also attenuated lead-induced abnormal renal structure. The results confirmed renoprotective effects of berberine in an animal model of lead-induced nephrotoxicity by molecular, biochemical, and histopathological analysis through inhibiting lipid peroxidation and enhancing antioxidant defense system mechanisms. Therefore, berberine makes a good candidate to protect against the deleterious effect of chronic lead intoxication.

Influence of iron on modulation of the antioxidant system in rat brains exposed to lead

The objective of this study was to evaluate markers of oxidative stress in the brains of rats exposed to lead acetate (Pb(C₂ H₃ O₂ )₂ ), either associated or not associated with ferrous sulfate (FeSO₄ ). A total of 36 weaning rats (Rattus norvegicus) were divided into 6 groups of six animals and exposed to lead acetate for six weeks. In the control group (control), the animals received deionized water. The Pb260 and Pb260 + Fe received 260 µM lead acetate, and the Pb1050 and Pb1050 + Fe received 1050 µM lead acetate. The Pb260 + Fe and Pb1050 + Fe were supplemented with 20 mg of ferrous sulfate/Kg body weight every 2 days. Group Fe received deionized water and ferrous sulfate. The rat brains were collected to analyze the enzymatic activity of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and the concentration of reduced glutathione (GSH), lipid peroxidation (TBARS), and total antioxidant substance (TAS) (DPPH^• technique). The activity of SOD and GPx in the experimental groups decreased compared to the control, together with the concentration of GSH (p < 0.05). For CAT analysis, SOD tended to increase in concentration in the experimental groups without a concomitant exposure to FeSO₄ , whereas GPx showed a slight tendency to increase in activity compared to the control. For TAS-DPPH^• , there was a decrease in the experimental groups (p < 0.05). According to the results, SOD, GPx, and GSH were affected by lead acetate and exposure to ferrous sulfate changed this dynamic. However, further studies are needed to verify whether ferrous sulfate acts as a protectant against the toxic effects of lead. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 813-822, 2017.

Gamma-Glutamyl Cysteine Attenuates Tissue Damage and Enhances Tissue Regeneration in a rat Model of Lead-Induced Nephrotoxicity

Lead is a biohazardous metal that is commonly involved in human illness including renal injury. Although it is a non-redox reactive metal, lead-induced renal injury is largely based on oxidative stress. The current work aimed at exploring the possible protective effect of γ-glutamyl cysteine (γGC) against lead-induced renal injury. Rats were allocated to normal and γGC control groups, lead-treated group, and lead and γGC-treated group. γGC alleviated lead-induced renal injury as evidenced by attenuation of histopathological aberration, amelioration of oxidative injury as demonstrated by significant reduction in lipid and protein oxidation, elevation of total antioxidant capacity, and glutathione level. The activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was significantly elevated. γGC significantly decreased levels of the proinflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-1β and the activity of the apoptotic marker caspase-3. In addition, γGC reduced kidney lead content, enhanced weight gain, and improved renal function as demonstrated by reduced serum levels of urea and creatinine. Importantly, γGC upregulated proliferating cell nuclear antigen (PCNA) expression, denoting enhanced renal regenerative capacity. Together, our findings highlight evidence for alleviating effects of γGC against lead-induced renal injury that is potentially mediated through diminution of oxidative tissue injury, reduction of inflammatory response, attenuation of apoptosis, and enhancement of renal regenerative capacity.

Bioactive peptide carnosin protects against lead acetate-induced hepatotoxicity by abrogation of oxidative stress in rats

Context Oxidative stress is a common mechanism of liver injury. Carnosine is a dipeptide having strong antioxidant effects. Objectives We investigated the effects of carnosine on lead-induced hepatotoxicity and oxidative stress in rats. Materials and methods Animals received an aqueous solution of lead acetate (500 mg Pb/L in the drinking water) and/or daily oral gavage of carnosine (10 mg/kg) for 8 weeks. Rats were then weighed and used for the biochemical (commercial kits), molecular (standard chemical methods) and histological (microscopic) evaluations. Results Lead-induced oxidative stress in liver tissue was indicated by a significant increase in the level of malondialdehyde (MDA) (8.25 ± 0.15 nmol/mg) as well as decrease in the level of total antioxidant capacity (TAC) (1.72 ± 0.25 μmol/g) and total thiol (SH) groups) 1.9 ± 0.22 μmol/g). Carnosine treatment decreased MDA (4 ± 0.08 nmol/mg), whereas it increased the contents of total thiol (3.25 ± 0.04 μmol/g) and TAC (3.44 ± 0.32 μmol/g) in the lead group. Carnosine also prevented the decreased body weight (p < 0.001), albumin (p < 0.05) and total protein levels (p < 0.001) and increased liver weight (p < 0.05) and activates of hepatic enzymes (p's < 0.001) (alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and lactate dehydrogenase) in the lead group. Furthermore, histopathological study showed that carnosine attenuates liver damage by decreasing necrosis and infiltration of inflammatory cells. Conclusion Carnosine prevented lead-induced hepatotoxicity, indicated by molecular, biochemical and histopathological analyses through inhibiting lipid peroxidation and enhancing antioxidant defence systems. Therefore, carnosine makes a good candidate to protect against the deleterious effect of chronic lead intoxication.

Effects of Naringenin on Oxidative Stress and Histopathological Changes in the Liver of Lead Acetate Administered Rats

Lead has several adverse effects on the body due to one of the environmental pollutants. We aimed to determine the effects of naringenin on the oxidative stress and the hepatic damage against lead acetate treatment in the liver of male rats. Naringenin was administered by orogastric gavage (50 mg/kg) and lead acetate was given as daily 500 parts per million in drinking water for 4 weeks. Lead and antioxidant activities were measured, and histopathological evaluation was performed in the liver. Lead concentrations, malondialdehyde, and antioxidant activity were restored by the naringenin. The grade of necrosis, hydropic degeneration, and hepatic cord disorganization was decreased by the naringenin. However, there were no differences in the degree of sinusoidal congestion, hepatic steatosis, and capsular fibrosis between lead acetate and naringenin + lead acetate groups. We can suggest that naringenin has antioxidant and chelating effects in the liver. Nevertheless, this effect is not enough against the lead acetate induced hepatic injury.

Antioxidant protection of gallic acid against toxicity induced by Pb in blood, liver and kidney of rats

The effect of the antioxidant gallic acid (GA) on Pb toxicity in blood, liver and kidney was investigated in the present study. Rats Wistar received Pb nitrate (50 mg/Kg/day, i.p., 5 days) followed by GA (13.5 mg/Kg, p.o., 3 days) or a chelating agent (EDTA, 55 mg/Kg, i.p.). As result, Pb decreased body weight, hematocrit and blood δ-aminolevulinic acid dehydratase (ALA-D) activity. In addition, high Pb levels were observed in blood and tissues, together with increased (1) lipid peroxidation in erythrocytes, plasma and tissues, (2) protein oxidation in tissues and (3) plasma aspartate transaminase (AST) levels. These changes were accompanied by decreasing in antioxidant defenses, like superoxide dismutase (SOD) activity in tissues and catalase (CAT) activity and reduced glutathione (GSH) in liver. GA was able to reverse Pb-induced decrease in body weight and ALA-D activity, as well as Pb-induced oxidative damages and most antioxidant alterations, however it did not decrease Pb bioaccumulation herein as EDTA did. Furthermore, EDTA did not show antioxidant protection in Pb-treated animals as GA did. In conclusion, GA decreased Pb-induced oxidative damages not by decreasing Pb bioaccumulation, but by improving antioxidant defenses, thus GA may be promising in the treatment of Pb intoxications.

Effects of isoquinoline alkaloid berberine on lipid peroxidation, antioxidant defense system, and liver damage induced by lead acetate in rats

OBJECTIVES

Liver is considered a target organ affected by lead toxicity. Oxidative stress is among the mechanisms involved in liver damage. Here we investigated the effects of the natural alkaloid berberine on oxidative stress and hepatotoxicity induced by lead in rats.

METHODS

Animals received an aqueous solution of lead acetate (500 mg Pb/l in the drinking water) and/or daily oral gavage of berberine (50 mg/kg) for 8 weeks. Rats were then weighed and used for the biochemical, molecular, and histological evaluations.

RESULTS

Lead-induced oxidative stress, shown by increasing lipid peroxidation along with a concomitant decrease in hepatic levels of thiol groups, total antioxidant capacity, the activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase, and reduced versus oxidized glutathione ratio. Berberine corrected all the disturbances in oxidative stress markers induced by lead administration. Berberine also prevented the elevated levels of enzymes (alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase) and the decrease in body weight and albumin. The protective effects of berberine were comparable with silymarin. Furthermore, berberine attenuated liver damage, shown by decreased necrosis and inflammatory cell infiltration.

DISCUSSION

Berberine represents a potential therapeutic option against lead-induced hepatotoxicity through inhibiting lipid peroxidation and enhancing antioxidant defenses.

CONCLUSION

Berberine exerted protective effects on lead-induced oxidative stress and hepatotoxicity in rats.

Guignardones P-S, New Meroterpenoids from the Endophytic Fungus Guignardia mangiferae A348 Derived from the Medicinal Plant Smilax glabra

Four new meroterpenoids, guignardones P-S (1-4), and three known analogues (5-7) were isolated from the endophytic fungal strain Guignardia mangiferae A348. Their structures were elucidated on the basis of spectroscopic analysis and single crystal X-ray diffraction. All the isolated compounds were evaluated for their inhibitory effects on SF-268, MCF-7, and NCI-H460 human cancer cell lines. Compounds 2 and 4 exhibited weak inhibitions of cell proliferation against MCF-7 cell line.

Perinatal exposure to lead: reduction in alterations of brain mitochondrial antioxidant system with calcium supplement

Lead (Pb) is a potent neurotoxicant that causes several neurochemical and behavioral alterations. Previous studies showed that the gestational and lactational exposure to Pb reduces the cholinergic and aminergic systems, and behavior of rats. The present study was designed to examine the protective effects of calcium supplementation against Pb-induced oxidative stress in cerebellum and hippocampus of brain at postnatal day (PND) 21, PND 28, PND 35, and PND 60. Pregnant rats were exposed to 0.2 % Pb (Pb acetate in drinking water) from gestational day 6 (GD 6) and pups were exposed through maternal milk till weaning (PND 21). We found that the activity of serum ceruloplasmin oxidase (Cp), mitochondrial manganese superoxide dismutase (Mn-SOD), copper zinc superoxide dismutase (Cu/Zn-SOD), glutathione peroxidase (GPx), catalase (CAT), and xanthine oxidase (XO) enzyme activities were decreased, whereas the malondialdehyde (MDA) levels increased in the cerebellum and hippocampus of Pb-exposed rats. These changes were more prominent at PND 35 and greater in hippocampus compared to cerebellum. Among the enzyme activities, Mn-SOD and Cu/Zn-SOD showed maximum decrease compared to GPx, CAT, XO, and Cp. Furthermore, 0.02 % calcium supplementation together with 0.2 % Pb significantly reversed the Pb-induced alterations in the enzyme activities, and MDA levels. In conclusion, these data suggest that early life exposure to Pb induce alterations in the mitochondrial antioxidant system of brain regions which remain for long even after Pb exposure has stopped. Calcium supplementation may potentially be beneficial in treating Pb toxicity in the developing rat brain.

Antioxidant and Anti-Inflammatory Activities of Phenolic-Enriched Extracts of Smilax glabra

Smilax glabra Roxb. has been used for a long time as both food and folk medicine. In the present study, phenolic-enriched extract of S. glabra (PEESG) was extracted with 70% ethanol and purified by HP-20 column chromatography. Its antioxidant and anti-inflammatory activities were evaluated by radical scavenging assay, reducing power determination, and lipopolysaccharide (LPS)-induced RAW264.7 cells assays, respectively. PEESG exhibited obviously scavenging capacity for DPPH and ABTS radicals, as well as significant reducing power for ferric ion. Particularly, PEESG (12.5–50 μg/mL) showed a significantly higher efficiency for scavenging ABTS than that of ascorbic acid and no significant difference with ascorbic acid for DPPH scavenging. PEESG also possessed a significant suppression effect on proinflammatory mediators production, such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), in LPS-induced RAW264.7 cells. In addition, the main ingredients of PEESG were identified using ultrahigh pressure liquid chromatography coupled to electrospray mass spectrometry (U-HPLC-ESI-MS). Seventeen components, including 5-O-caffeoylshikimic acid, neoastilbin, astilbin, neoisoastilbin, isoastilbin, engetin and isoengeletin were identified. These findings strongly suggest the potential of PEESG as a natural antioxidant and anti-inflammatory agent.

Smilax China root extract detoxifies nicotine by reducing reactive oxygen species and inducing CYP2A6

Resveratrol has a beneficial effect of lowering reactive oxygen species (ROS) and reduces cellular oxidative stress. We hypothesized that ethanol extract of Smilax china root (EESC) rich in resveratrol (RES) and oxyresveratrol (OXY) could reduce ROS caused by nicotine and promoting nicotine turnover by induction of CYP2A6. The amount of cotinine converted from nicotine was quantified by the direct barbiturate assay method. Expression of CYP2A6 was unregulated by RES, OXY, or EESC, respectively. Pretreatment of RES (50, 100, and 250 μM), OXY (50, 100, and 250 μM), and RES+OXY (50 and 100 μM) inhibited cytotoxicity and ROS production caused by nicotine in a dose-dependent manner. EESC pretreatment (1.8 mg/mL) increased cell viability by 1.5-fold higher than the control (nicotine only), and lowered cellular ROS levels. A significant amount of the conversion of nicotine to cotinine was observed in EESC pretreatment by CYP2A6 induction in HepG2 cells. These results suggested that hepatic induction of CYP2A6 and ROS reduction by EESC activate nicotine metabolism and reduce cellular oxidative stress.

PRACTICAL APPLICATION

Nicotine exposure due to smoking is very concerning because it is the major factor for lung diseases and cardiovascular disorders. It is necessary to examine natural ingredients that can detoxify from nicotine to cotinine as well as neutralize free radicals induced from nicotine. Results from the current study suggest potential applications of Smilax china root for detoxification of nicotine in the food industry.