Aqueous extract of Monodora myristica ameliorates cadmium-induced hepatotoxicity in male rats

Tetramethylpyrazine Antagonizes the Subchronic Cadmium Exposure-Induced Oxidative Damage in Mouse Livers via the Nrf2/HO-1 Pathway

Hepatic oxidative stress is an important mechanism of Cd-induced hepatotoxicity, and it is ameliorated by TMP. However, this underlying mechanism remains to be elucidated. To investigate the mechanism of the protective effect of TMP on liver injuries in mice induced by subchronic cadmium exposure, 60 healthy male ICR mice were randomly divided into five groups of 12 mice each, namely, control (CON), Cd (2 mg/kg of CdCl2), Cd + 100 mg/kg of TMP, Cd + 150 mg/kg of TMP, and Cd + 200 mg/kg of TMP, and were acclimatized and fed for 7 d. The five groups of mice were gavaged for 28 consecutive days with a maximum dose of 0.2 mL/10 g/day. Except for the control group, all groups were given fluoride (35 mg/kg) by an intraperitoneal injection on the last day of the experiment. The results of this study show that compared with the Cd group, TMP attenuated CdCl2-induced pathological changes in the liver and improved the ultrastructure of liver cells, and TMP significantly decreased the MDA level (p < 0.05) and increased the levels of T-AOC, T-SOD, and GSH (p < 0.05). The results of mRNA detection show that TMP significantly increased the levels of Nrf2 in the liver compared with the Cd group as well as the HO-1 and mRNA expression levels in the liver (p < 0.05). In conclusion, TMP could inhibit oxidative stress and attenuate Cd group-induced liver injuries by activating the Nrf2 pathway.

Nano-Selenium Alleviates Cadmium-Induced Acute Hepatic Toxicity by Decreasing Oxidative Stress and Activating the Nrf2 Pathway in Male Kunming Mice

Cadmium (Cd) is known as a highly toxic heavy metal and has been reported to induce hepatotoxicity in animals. Nano-selenium (NSe) is an antioxidant that plays many biological roles such as oxidative stress alleviation. The purpose of this study is to explore the mechanism of action by which NSe inhibits Cd-induced hepatic toxicity and oxidative stress. Sixty eight-week-old male Kunming mice were randomly divided into four groups (15 mice per group). The control group and cadmium groups received distilled water, whereas the sodium-selenite group received 0.2 mg/kg SSe and the NSe group received 0.2 mg/kg NSe intragastrically for 2 weeks. On the last day, all the other groups were treated with Cd (126 mg/kg) except for the control group. The results obtained in this study showed that NSe alleviated Cd-induced hepatic pathological changes. Furthermore, NSe reduced the activities of ALT and AST as well as the content of MDA, while elevated the activities of T-AOC, T-SOD and GSH (P < 0.05). In addition, the NSe group significantly increased mRNA expressions of Nrf2 pathway related molecules (Nrf2, HO-1, NQO-1, GST, GSH-Px, CAT and SOD) compared to the Cd group (P < 0.05). In conclusion, NSe shows its potentiality to reduce Cd-induced liver injury by inhibiting oxidative stress and activating the Nrf2 pathway.

Sterculia tragacantha Lindl Leaf Extract Ameliorates STZ-Induced Diabetes, Oxidative Stress, Inflammation and Neuronal Impairment

Background

Sterculia tragacantha is a medicinal plant commonly used in the western part of Nigeria, for managing diabetes mellitus. However, there is a dearth of scientific information on the antidiabetic and neuroprotective properties of the plant.

Methods

The in silico, in vitro and in vivo models were used to evaluate the antioxidants, antidiabetic, anti-inflammatory and neuroprotective potential of aqueous extract of Sterculia tragacantha leaf (AESTL) in streptozotocin (STZ)-induced diabetic rats. Thirty (30) male albino rats (155.34±6.33 g) were intraperitoneal injected with 40 mg/kg of freshly prepared streptozotocin and were divided into 5 groups (A-E) of 6 animals each. Groups A–D were treated with 0, 150 and 300 mg/kg of AESTL, and 200 mg/kg body weight of metformin respectively, while group E serve as the normal control.

Results

The results of in vitro analysis revealed dose-dependent antioxidant activities; ABTS (IC₅₀ = 63.03±2.57 μg/mL), DPPH (117.49±2.35 μg/mL), FRAP (15.19±0.98 mmol/100g), TAC (43.38±0.96 mg/100g), hypoglycaemic effect; α-amylase (IC₅₀ = 77.21±4.35 μg/mL) and α-glucosidase (IC₅₀ = 443.25±12.35), and anti-cholinesterase; AChE (IC₅₀ = 113.07±3.42 μg/mL) and BChE (IC₅₀ = 87.50±4.32 μg/mL) activities of AESTL. In vivo study revealed dose-dependent hypoglycemic effect and body weight improvement in rats treated with the AESTL. In addition, AESTL improved the antioxidant status and attenuated STZ-induced dysregulations of Na⁺-K⁺-ATPase, cholinesterases and neurotransmitters in the brain tissue of experimental rats. The results also demonstrated that AESTL could regulate anti-inflammatory response via inhibition of COX-2/NO signaling axis in the brain of diabetic rats. Molecular docking analysis revealed that epicatechin and procyanidin B2, the bioactive compounds from AESTL, docked well to the binding cavities of acetylcholinesterase, butyrylcholinesterase, α-amylase and α-glucosidase with binding affinities ranges between –8.0 and –11.4 kcal/mol, suggesting that these compounds are the bioactive component that could be responsible for the antidiabetic and neuroprotective activities of AESTL.

Conclusion

The results of the present study strongly suggested that the AESTL extract could be very useful for halting diabetes progression and its associated neuroinflammation complications.

Potential antioxidant effects of Narcissus tazetta phenolic compounds against cadmium chloride-induced hepatotoxicity in Swiss albino mice

Narcissus tazetta (Amaryllidaceae) is a medicinal plant widely used for cut flowers and potted ornamental plant in Tunisia flora. The current study evaluated the phenolic composition and antioxidant properties of its flower extracts and investigated its potential protective activity against cadmium chloride (CdCl₂)-induced hepatotoxicity in mice. Mice were divided into six groups of six each: group 1, serving as negative controls, received by intraperitoneal way only distilled water; group 2 received by intraperitoneal way CdCl₂ (0.16 mg/kg bw); groups 3 and 4 received CdCl₂ at the same dose of group 2 and 100 or 200 mg/kg bw of Narcissus tazetta flower extracts via oral route; groups 5 and 6, serving as positive controls, received only Narcissus tazetta flower extracts. Polyphenolic compounds of the extract were analyzed by colorimetric and high-performance liquid chromatography-mass spectrometry (HPLC-MS) methods. Total antioxidant activity and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging potential of the extract were estimated using colorimetric method. Results indicated that ethanolic flower extract contained high levels of total phenolic and flavonoid along with a strong total antioxidant and DPPH free radical scavenging activities. HPLC-MS analysis identified eight phenolic compounds, including rutin, kaempferol glycosides, and chlorogenic acids. The extract also exhibited marked hepatoprotective effects against CdCl₂ toxicity by reducing hepatic levels of malondialdehyde, advanced oxidation protein products, hydrogen peroxide, metallothioneins, and DNA degradation. Additionally, co-administration of Narcissus tazetta flower extracts lowered the plasma activities of transaminases, gamma glutamyl transpeptidase, and lactate dehydrogenase and increased hepatic levels of reduced glutathione, nonprotein thiols, vitamin C, and catalase activity. The hepatoprotective effects of the extract were demonstrated by histopathological improvement of liver disorders. The current study provided ethnopharmacological application of Narcissus tazetta flower extracts against CdCl₂-induced oxidative stress_, suggesting its chemoprevention role of its phenolic compounds as a natural antioxidant.

Nephroprotective and anti-inflammatory potential of aqueous extract from Persea americana seeds against cadmium-induced nephrotoxicity in Wistar rats

Cadmium is a toxic metal and poses a high environmental risk to animals and humans, alike. It is thus pertinent to search for medicinal plants in protecting against cadmium toxicity. This study aims at investigating the ability of aqueous extract of Persea americana seeds (AEPA) in ameliorating the toxic effects of cadmium in the kidneys of cadmium-exposed Wistar rats. Male Wistar rats were grouped into five, of six animals each. Different groups of animals received normal saline (control group), 200 mg/kg body weight AEPA, 400 mg/kg AEPA, and standard drug, Livolin Forte, respectively. A last group of animals was left untreated. To induce toxicity, all animals, except the control group, were exposed to cadmium (200 mg/L, as CdCl₂) in their main drinking water for 21 days. Biochemical analysis of serum kidney markers, oxidative stress and antioxidant status, as well as anti-inflammatory activities, was done using standard methods and kits. In silico analysis was performed on phytochemicals reported to be abundant in AEPA. Treatment with 400 mg/kg AEPA significantly reversed (P ≤ 0.05) the adverse effect of cadmium on serum creatinine, urea, uric acid and blood urea nitrogen, and restored (P ≤ 0.05) antioxidant status, evidenced by its significant effect on superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase, reduced glutathione, and lipid peroxidation activities. AEPA, at 400 mg/kg also exhibited significant anti-inflammatory effects, which was shown by reduced interleukin-2 and tumour necrosis factor α activities. Molecular docking of phytochemicals with the selected protein target also confirmed the therapeutic potential of AEPA. The study concluded that aqueous extract of AEPA protects against cadmium-induced kidney toxicity and inflammation.

Environmental toxicants, oxidative stress and health adversities: interventions of phytochemicals

OBJECTIVES

Oxidative stress is the most common factor mediating environmental chemical-induced health adversities. Recently, an exponential rise in the use of phytochemicals as an alternative therapeutics against oxidative stress-mediated diseases has been documented. Due to their free radical quenching property, plant-derived natural products have gained substantial attention as a therapeutic agent in environmental toxicology. The present review aimed to describe the therapeutic role of phytochemicals in mitigating environmental toxicant-mediated sub-cellular and organ toxicities via controlling cellular antioxidant response.

METHODS

The present review has covered the recently related studies, mainly focussing on the free radical scavenging role of phytochemicals in environmental toxicology.

KEY FINDINGS

In vitro and in vivo studies have reported that supplementation of antioxidant-rich compounds can ameliorate the toxicant-induced oxidative stress, thereby improving the health conditions. Improving the cellular antioxidant pool has been considered as a mode of action of phytochemicals. However, the other cellular targets of phytochemicals remain uncertain.

CONCLUSIONS

Knowing the therapeutic value of phytochemicals to mitigate the chemical-induced toxicity is an initial stage; mechanistic understanding needs to decipher for development as therapeutics. Moreover, examining the efficacy of phytochemicals against mixer toxicity and identifying the bioactive molecule are major challenges in the field.

Vitamin E protects against cadmium-induced sub-chronic liver injury associated with the inhibition of oxidative stress and activation of Nrf2 pathway

Hepatic oxidative stress, as one important mechanism of cadmium (Cd)-induced hepatic toxicity, could, as known, be ameliorated by vitamin E (VE). However, the underlying mechanism remains to be elucidated. To investigate whether the antioxidant vitamin E can protect against Cd-induced sub-chronic liver injury associated with oxidative stress and nuclear factor erythrocyte 2-related factor 2 (Nrf2) pathway, male Sprague-Dawley rats (nine-week-old) were randomly divided into four groups (eight rats/group), namely, control, VE (100 mg/kg VE), Cd (5 mg/kg CdCl₂) and VE+Cd (100 mg/kg VE+5 mg/kg CdCl₂), and received intragastric administration of Cd and/or VE for four weeks. Cd-exposure alone resulted in reduced liver weight, liver histological alteration and oxidative stress, accumulation of Cd in the liver, elevated ALT and AST concentrations in serum together with decreased mRNA and protein expressions of Nrf2 pathway related molecules (Nrf2, HO-1, NQO-1, GCLC, GCLM and GST). However, the co-treatment of Cd and VE significantly ameliorated the changes mentioned above, and promoted the expression of genes and proteins of Nrf2 pathway related molecules in comparison to the Cd-exposure alone. Our results indicate that the protective effect of VE against Cd-induced sub-chronic hepatic damage in rats is associated with the inhibition of oxidative stress and activation of Nrf2 pathway.

Antibiofilm and Enzyme Inhibitory Potentials of Two Annonaceous Food Spices, African Pepper (Xylopia aethiopica) and African Nutmeg (Monodora myristica)

Food pathogens represent an important health threat, and it is relevant to study the effect of foodstuffs such as spices which can inhibit bacterial growth. This study reports the antimicrobial, antibiofilm, and enzyme (Acetylcholinesterase, Butyrylcholinesterase, urease, tyrosinase) inhibitory activities of two medicinal food spices belonging to the Annonaceae family, Monodora myristica and Xylopia aethiopica. GC-MS (gas chromatography mass spectrometry) analysis of silylated samples of Methanol-Dicloromethane (50:50) extracts of both plants led to the identification of nine compounds in M. myristica and seven compounds in X. aethiopica. M. myristica and X. aethiopica had the same minimum inhibitory concentration (MIC) values of 0.625 mg/mL and 2.5 mg/mL on C. albicans and E. coli, respectively. However, M. myristica had better activity than X. aethiopica on Staphylococcus aureus, while Pseudomonas aeruginosa was more susceptible to X. aethiopica than M. myristica. The lowest MIC value was 0.1325 mg/mL, exhibited by M. myristica on S. aureus. Both extracts showed good antibiofilm activity. On S. aureus, at the same concentration, M. myristica had better antibiofilm activity than X. aethiopica. On E. coli and Candida albicans, X. aethiopica had better antibiofilm activity than M. myristica at the same concentration. X. aethiopica showed better violacein inhibition in Chromobacterium violaceum CV12472, as its percentage inhibition of violacein varied from 80.5% ± 3.0% at MIC to 5.6 ± 0.2 at MIC/8, as compared to M. myristica with 75.1% ± 2.5% at MIC and 15.5% ± 1.1% at MIC/8. The anti-motility activity by swimming and swarming inhibition on P. aeruginosa PA01 was low at test concentrations and in both models, M. myristica showed higher motility inhibition than X. aethiopica. Although in enzyme inhibitory assays all extracts had low inhibitions compared to standards tested at the same concentrations, the results show that these plants can be used to manage food-borne infections.

Exposure to arsenite and cadmium induces organotoxicity and miRNAs deregulation in male rats

Sodium arsenite (NaAsO₂) and cadmium chloride (CdCl₂) are two prime examples of un-biodegradable compounds that accumulate in the ecosystems causing great threats to human health and produce severe adverse effects. However, their joint toxicities are poorly understood in mammals. This study aimed to identify the effect of exposure to NaAsO₂ (5 mg/kg, by oral gavage) and CdCl₂ (1 mg/kg injected interperitoneal, i.p.) either alone or in combinations after 14 and 28 days on oxidative stress, antioxidant enzyme activities, and histopathological changes. The results revealed a downregulation of miR-146a also, in miR-let7a after 14 days and a notable upregulation after 28 days. However, administrations of their combinations for 14 days caused downregulated miR-146a and miR-let7a. However, upregulation miR-let7a was observed only after 28 days. Organotoxicity of liver results in a remarkable increase in oxidative stress biomarkers by the two metals either alone or in combinations. A remarkable decrease was noted in an antioxidant enzyme activity indicating a defect in the antioxidant defense system. Also, CdCl₂ alone showed remarkable liver histopathological changes. This study concluded that there was a close relationship of high epigenetic changes as deregulation of both miR-146a and miR-let7a as a result of the joint toxicity of both compounds, and ultimately major changes in hepatic tissues that may lead to cell transformations. However, further studies are needed to investigate the target genes for those miRNAs.

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.

Glutathione Might Attenuate Cadmium-Induced Liver Oxidative Stress and Hepatic Stellate Cell Activation

The liver is a major organ involved in cadmium (Cd)-induced oxidative damage. Following liver injury, hepatic stellate cells (HSCs) are activated to participate in the wound healing process, but also facilitate liver fibrosis. Previous studies have observed fibrogenic effects of Cd on liver. However, the oxidative stress mechanisms of Cd-induced HSC activation as well as whether administration of glutathione (GSH) alleviates this activation, remain unclear. In this study, 24 rats were divided randomly into four experimental groups: control, GSH-treated, Cd-treated, and Cd + GSH-treated. After 4 weeks, the liver injury index, HSC-specific activation markers, oxidative stress-related antioxidants, and enzyme activities and signals were measured. Cd uptake and the generation of reactive oxygen species (ROS) in hepatocytes were detected by mass cytometry and fluorescence microscopy, respectively. Levels of aspartate aminotransferase, xanthine oxidase, γ-glutamyl transpeptidase, and α-smooth muscle actin (αSMA) were significantly increased in Cd-treated rats. Activated HSCs positive for αSMA expression and excess collagen deposition were detected in the Cd-treated group. In contrast, activities of the antioxidant enzymes superoxide dismutase, glutathione peroxidase, and catalase were reduced. Supplementation with GSH reversed some of the Cd-induced effects and increased the protein level of phosphorylated (p)-P65 while decreasing p-JNK. Pretreatment with GSH lowered Cd uptake and ROS generation in hepatocytes in vitro. These results indicate that administration of GSH was effective in attenuating Cd-induced oxidative stress via decreasing Cd uptake, restoring the activities of oxidative enzymes, activating NF-κB, inhibiting the JNK signaling pathway, and preventing excessive ROS generation and HSC activation.

Tinospora cordifolia extract prevents cadmium-induced oxidative stress and hepatotoxicity in experimental rats

Background

Cadmium (Cd) pollution is of serious concern due to its toxic effects in both humans and animals. The study investigates the protective effect of Tinospora cordifolia stem methanolic extract (TCME) on Cd induced hepatotoxicity.

Objective(s)

The objective of the study was to explore the hepatoprotective effects of T. cordifolia extract.

Materials and methods

Rats were administered orally with Cd (5 mg/kg) and TCME (100 mg/kg) for 28 days. At the end of the treatment period, serum and liver tissues homogenates were subjected to biochemical analysis.

Results

Cd treated rats showed increased activities of the serum marker enzymes of liver damage such as AST and ALT along with increased levels of LPO and protein carbonyl content in liver tissues. Cd treatment also leads to decreased activities of endogenous antioxidants (SOD, CAT, GSH, GPx and GST), membrane ATPases (Na⁺K⁺ATPase, Ca²⁺ATPase and Mg²⁺K⁺ATPase) and the tissue glycoprotein levels (hexose, fucose, hexosamine and sialic acid). Histological analysis revealed vacuolar degeneration of hepatocytes with focal necrosis upon Cd administration. TCME co-treatment restored the biochemical and histological alterations caused by Cd intoxication to near normal levels.

Conclusion

The results of the present investigation reveal the hepatoprotective nature of T.cordifolia against Cd induced hepatotoxicity.

Stone quarrying induces organ dysfunction and oxidative stress in Meriones libycus

Exposure to heavy metal-containing dust arising from stone quarrying may cause severe health problems. The aim of this study was to evaluate the impact of stone quarrying in Riyadh (Saudi Arabia) on the Libyan jird Meriones libycus. Soil samples and jirds were collected from four sites located at different distances from the quarrying area. Soil from the first (500 m away from the quarry) and second (1800 m away) sites showed a significant increase in cadmium (Cd), lead (Pb), nickel (Ni), and vanadium (V) when compared with the reference site (38,000 m away). Jirds at these sites exhibited significant increases in liver, kidney, lung, and fur levels of Cd, Pb, Ni, and V. Serum transaminases, creatinine, and malondialdehyde (MDA) levels were significantly increased in jirds, whereas reduced glutathione (GSH) levels decreased. Liver, kidney, and lung tissues of jirds, collected from the first and second sites, showed significantly increased MDA and decreased GSH levels. Additionally, animals at both sites showed altered hematological parameters and several histopathological changes in their liver, kidney, and lung. Soil and animals at the third site (7300 m away) showed no significant changes. Thus, our study showed the impact and hazardous effects of quarrying on the liver, kidney, lung, and hemogram of M. libycus. These findings can provide scientific evaluation for studying the impact of quarrying on the workers and communities living close to the studied area.

Modulatory Effect of Methanol Extract of Piper guineense in CCl₄-Induced Hepatotoxicity in Male Rats

This study seeks to investigate the possible protective role of the methanol extract of Piper guineense seeds against CCl₄-induced hepatotoxicity in an animal model. Hepatotoxicity was induced by administering oral doses of CCl₄ (1.2 g/kg bw) three times a week for three weeks. Group 1 (Control) and Group 2 (CCl₄) were left untreated; Piper guineense (PG; 400 mg/kg bw) was administered to Group 3 (T₁) by oral gavage for 14 days prior to the administration of CCl₄ and simultaneously with CCl₄; PG (400 mg/kg bw) was administered simultaneously with CCl₄ in Group 4 (T₂); and Livolin forte (20 mg/kg bw) was administered simultaneously with CCl₄ in Group 5 (T₃), the standard drug group. The administration of CCl₄ induces histopathological alteration in the liver, with concomitant increased activities of serum hepatic marker enzymes associated with increased levels of lipid peroxidation. Similarly, there was decrease in non-enzymatic (reduced glutathione) and enzymatic antioxidants (glutathione S-transferase), superoxide dismutase, and catalase. An elevation in serum triglyceride and total cholesterol levels was noticed along with decreased levels of serum total protein. Treatment with PG 400 mg/kg bw exhibited excellent modulatory activity with respect to the different parameters studied by reversing all the above-mentioned biochemical changes significantly in the experimental animals. These results suggest that PG offered protection comparable to that of Livolin forte with better efficacy when pre-treated with 400 mg/kg bw 14 days prior to CCl₄-exposure.