Grape seed proanthocyanidins protects against cadmium induced oxidative pancreatitis in rats by attenuating oxidative stress, inflammation and apoptosis via Nrf-2/HO-1 signaling

Tempol mitigates inflammation, oxidative stress, and histopathological alterations of cadmium-induced parotid gland injury in rats

Cadmium (Cd) is a potent environmental pollutant that causes functional and structural damage to the salivary glands. Tempol (TEM) has powerful antioxidant activity that can potentially preserve organ function.

AIMS

This study was designed to investigate the protective effects of TEM on Cd-induced toxicity in rat parotid salivary glands.

MATERIALS AND METHODS

Twenty-four adult Wistar male rats were randomly assigned to four equal groups: control, TEM (27.5 g/100 ml), Cd (0.6 g/100 ml), and TEM plus Cd (at the same doses). All treatments were dissolved in distilled water and administered subcutaneously four times a week for four weeks. Parotid gland tissues were isolated and subjected to molecular and histo-biochemical assessments.

KEY FINDINGS

TEM exerted a prophylactic effect against Cd-induced toxicity in the parotid glands by controlling inflammation through the downregulation of toll-like receptor 4/myeloid differentiation primary response 88/nuclear factor kappa B/ interleukin-1 beta mRNA expression, upregulation of aquaporin-5 mRNA expression, improvement of the oxidant/antioxidant status in the parotid gland, mitigation of endoplasmic reticulum stress, and repair of the associated histological and ultrastructural abnormalities.

SIGNIFICANCE

TEM protects against Cd-induced toxicity in the parotid glands of rats, attributable at least in part to its anti-inflammatory and antioxidant properties, as well as its ability to inhibit ER stress and facilitate glandular repair. However, the protective effects of TEM did not reach the levels observed in the control group. TEM could be a promising clinical candidate for protecting the salivary glands, particularly in high-risk groups such as workers exposed to Cd and cigarette smokers.

The attenuating effects of serine against cadmium induced immunotoxicity through regulating M1/M2 and Th1/Th2 balance in spleen of C57BL/6 mice

Cadmium (Cd) has adverse effects on organisms. Serine is an essential nutritional factor and its nutritional value is extremely high for body. To explore the effects of serine on spleen toxicity induced by Cd in mice, cadmium chloride (CdCl2, 50 mg/L) and serine (50 g/L) were individually administered or co-administrated in drinking water of mice for 18 weeks. Results demonstrated that Cd exposure induced splenic toxicity and serine against the toxicity damage caused by Cd in mice. Under Cd stress, trace element homeostasis was disturbed, the mice's body weight and spleen index were increased, and splenic morphology and ultrastructure were altered. Furthermore, Cd exposure led to the cell populations disorder, which in turn triggers cell death. Notably, Cd treatment induced oxidative stress and inflammation, increased M1/M2 (iNOS, CD68) and Th1/Th2 (T-bet, CD4) levels, decreased M1/M2 (Arg1) and Th1/Th2 (GATA3) levels, while disrupted the macrophages and lymphocytes homeostasis, which trigged apoptosis and pyroptosis in spleen. In contrast, serine supplementation changed the levels of Cd and other elements, weakened Cd-induced tissue damage and inflammation, enhanced antioxidant capacity, significantly restored cell homeostasis, and effectively inhibited Cd-induced apoptosis and pyroptosis in the spleen. Shortly, the results verified that serine had an ameliorating toxicity effect and restored the M1/M2 and Th1/Th2 balance, restrained apoptosis and pyroptosis induced by Cd.

Enhancement of Thermal Tolerance and Growth Performances of Asian Seabass (Lates calcarifer) Fed with Grape Extract Supplemented Feed

Cold snaps during the winter present a critical challenge for Asian seabass (Lates calcarifer) in Taiwan, as sudden temperature drops significantly affect their growth and survival. This study explores the effects of dietary grape extract (GE) from Vitis vinifera on the growth performance, oxidative stress regulation, and thermal tolerance of this commercially valuable fish. Over a 60-day feeding trial, four dietary groups were tested: a control diet without GE and three diets supplemented with GE at 2% (GE20), 3% (GE30), and 4% (GE40) with commercial feed. The results demonstrated that GE supplementation positively influenced growth, with the GE20 group achieving the best weight gain and feed conversion ratio among all groups. The upregulation of the growth-related gene igf-1 in the liver of the GE20 group further supported its superior growth performance. Additionally, GE-fed groups showed increased expression of antioxidant-related genes sod1 and sod2 in the liver, while gpx1 exhibited a significant increase only in the GE20 group, indicating enhanced antioxidant defenses. Cat gene expression remained unchanged, and higher GE doses reduced the expression of gpx1, cat, and igf-1. Furthermore, GE supplementation improved cold tolerance in all treated groups compared to the control. These findings suggest that dietary GE at 20 g/kg is particularly effective in enhancing growth performance and cold tolerance in Asian seabass, offering a promising strategy for boosting fish health and adaptability in aquaculture.

Subacute cadmium exposure changes different metabolic functions, leading to type 1 and 2 diabetes mellitus features in female rats

Cadmium (Cd) is a heavy metal that acts as endocrine disrupting chemical (EDC). Few studies have investigated the effects of Cd exposure on metabolic dysfunctions, such as type 1 and 2 diabetes mellitus (T1DM and T2DM). Thus, we assessed whether subacute Cd exposure at occupational levels causes abnormalities in white adipose tissue (WAT), liver, pancreas, and skeletal muscle. We administered cadmium chloride (CdCl2) (100 ppm in drinking water for 30 days) to female rats and evaluated Cd levels in serum and metabolic organs, morphophysiology, inflammation, oxidative stress, fibrosis, and gene expression. High Cd levels were found in serum, WAT, liver, pancreas, and skeletal muscle. Cd-exposed rats showed low adiposity, dyslipidemia, insulin resistance, systemic inflammation, and oxidative stress compared to controls. Cd exposure reduced adipocyte size, hyperleptinemia, increased cholesterol levels, inflammation, apoptosis and fibrosis in WAT. Cd-exposed rats had increased liver cholesterol levels, insulin receptor beta (IRβ) and peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC1α) expression, karyomegaly, inflammation, and fibrosis. Cd exposure reduced insulin levels and pancreatic islet size and increased inflammation and fibrosis. Cd exposure reduced skeletal muscle fiber diameter and increased IR expression and inflammation. Finally, strong positive correlations were observed between serum, tissue Cd levels, abnormal morphology, tissue inflammation and fibrosis. Thus, these data suggest that subacute Cd exposure impairs WAT, liver, pancreas and skeletal muscle function, leading to T1DM and T2DM features and other complications in female rats.

Heavy metals in cigarette smoke strongly inhibit pancreatic ductal function and promote development of chronic pancreatitis

BACKGROUND AND AIMS

Smoking is recognised as an independent risk factor in the development of chronic pancreatitis (CP). Cystic fibrosis transmembrane conductance regulator (CFTR) function and ductal fluid and bicarbonate secretion are also known to be impaired in CP, so it is crucial to understand the relationships between smoking, pancreatic ductal function and the development of CP.

METHODS

We measured sweat chloride (Cl-) concentrations in patients with and without CP, both smokers and non-smokers, to assess CFTR activity. Serum heavy metal levels and tissue cadmium concentrations were determined by mass spectrometry in smoking and non-smoking patients. Guinea pigs were exposed to cigarette smoke, and cigarette smoke extract (CSE) was prepared to characterise its effects on pancreatic HCO3 - and fluid secretion and CFTR function. We administered cerulein to both the smoking and non-smoking groups of mice to induce pancreatitis.

RESULTS

Sweat samples from smokers, both with and without CP, exhibited elevated Cl- concentrations compared to those from non-smokers, indicating a decrease in CFTR activity due to smoking. Pancreatic tissues from smokers, regardless of CP status, displayed lower CFTR expression than those from non-smokers. Serum levels of cadmium and mercury, as well as pancreatic tissue cadmium, were increased in smokers. Smoking, CSE, cadmium, mercury and nicotine all hindered fluid and HCO3 - secretion and CFTR activity in pancreatic ductal cells. These effects were mediated by sustained increases in intracellular calcium ([Ca2+]i), depletion of intracellular ATP (ATPi) and mitochondrial membrane depolarisation.

CONCLUSION

Smoking impairs pancreatic ductal function and contributes to the development of CP. Heavy metals, notably cadmium, play a significant role in the harmful effects of smoking.

KEY POINTS

Smoking and cigarette smoke extract diminish pancreatic ductal fluid and HCO3 - secretion as well as the expression and function of CFTR Cd and Hg concentrations are significantly higher in the serum samples of smokers Cd accumulates in the pancreatic tissue of smokers.

Synergistic Effect of a Flavonoid-Rich Cocoa-Carob Blend and Metformin in Preserving Pancreatic Beta Cells in Zucker Diabetic Fatty Rats

The loss of functional beta-cell mass in diabetes is directly linked to the development of diabetic complications. Although dietary flavonoids have demonstrated antidiabetic properties, their potential effects on pancreatic beta-cell preservation and their synergistic benefits with antidiabetic drugs remain underexplored. We have developed a potential functional food enriched in flavonoids by combining cocoa powder and carob flour (CCB), which has shown antidiabetic effects. Here, we investigated the ability of the CCB, alone or in combination with metformin, to preserve pancreatic beta cells in an established diabetic context and their potential synergistic effect. Zucker diabetic fatty rats (ZDF) were fed a CCB-rich diet or a control diet, with or without metformin, for 12 weeks. Markers of pancreatic oxidative stress and inflammation, as well as relative beta-cell mass and beta-cell apoptosis, were analyzed. Results demonstrated that CCB feeding counteracted pancreatic oxidative stress by enhancing the antioxidant defense and reducing reactive oxygen species. Moreover, the CCB suppressed islet inflammation by preventing macrophage infiltration into islets and overproduction of pro-inflammatory cytokines, along with the inactivation of nuclear factor kappa B (NFκB). As a result, the CCB supplementation prevented beta-cell apoptosis and the loss of beta cells in ZDF diabetic animals. The observed additive effect when combining the CCB with metformin underscores its potential as an adjuvant therapy to delay the progression of type 2 diabetes.

Dietary grape seed proanthocyanidin extract supplementation improves antioxidant capacity and lipid metabolism in finishing pigs

Grape seed proanthocyanidin extract (GSPE) plays a significant role in body health, including improving antioxidant capacity and maintaining lipid metabolism stability. However, whether dietary GSPE supplementation can improve lipid metabolism in finishing pigs remains unclear. Here 18 castrated male Duroc × Landrace × Yorkshire finishing pigs were randomly divided into three groups with six replicates and one pig per replicate. Pigs were fed a basal diet (control), a basal diet supplemented with 100 mg/kg GSPE, or a basal diet supplemented with 200 mg/kg GSPE for 30 days. Antioxidant analysis showed that dietary 200 mg/kg GSPE supplementation increased glutathione, total antioxidant capacity and glutathione peroxidase levels, and reduced malondialdehyde levels in serum, muscle and liver. Dietary 200 mg/kg GSPE supplementation also upregulated the mRNA and protein levels of nuclear-related factor 2 (Nrf2). Lipid metabolism analysis showed that dietary GSPE supplementation increased serum high-density lipoprotein cholesterol levels and reduced serum triglyceride and total cholesterol levels. Besides, GPSE upregulated the mRNA expression of lipolysis- and fatty acid oxidation-related genes downregulated the mRNA expression of lipogenesis-related genes, and activated the AMPK signal in finishing pigs. Together, we provided evidence that dietary GSPE supplementation improved the antioxidant capacity and lipid metabolism in finishing pigs.

Otoprotective Effects of Quercetin Against Oxidative Damage in the Rat's Cochlea Induced by Noise and Silver Nanoparticles

The aim of this study was to investigate the otoprotective effects of Quercetin (Que) against both noise-induced hearing loss (NIHL) and the ototoxicity of silver nanoparticles (SNPs) in rats. Forty-two male Wistar rats were divided into seven groups (n = 6): control, SNPs, Que (100 mg/kg) plus SNPs (100 mg/kg), noise (104 dB), Que plus noise, noise plus SNPs, and noise plus Que plus SNPs. In the weight change results, there was no significant difference between the groups exposed to noise plus SNPs and SNPs compared to the control group. However, animals had significant changes in DPOAE amplitude at 1 and 3 days post-exposure when compared to baseline. Additionally, the DPOAE value of rats administered with Que plus SNPs was higher than in all other groups. Que also decreased the levels of TACT, MDA, IL-6, TNF-α, and NOX3 in the groups exposed to noise and SNPs and increased the SOD level and expression of myosin heavy chain VII (MYH7) and β-tubulin III (TUBB3) proteins. Furthermore, Que decreased structural changes in the animals' cochlea. Our findings indicate that pretreatment with Que efficiently counteracted the adverse effects of noise and SNPs on inner hair cell, outer hair cell, and nerve cells, which are responsible for high-frequency perception.

Protective effects of cardamom aqueous extract against tamoxifen-induced pancreatic injury in female rats

Tamoxifen (TAM) is a commonly used drug for breast cancer treatment. Although effective, TAM has deleterious effects on many organs. The toxic effects of TAM on the pancreas and the underlying mechanisms however, have not fully investigated. In the present study, we investigated the effects of TAM on the pancreatic tissue in female rats. We also examined whether cardamom aqueous extract (CAE) protects against TAM-induced pancreatic injury. TAM-intoxicated rats were injected with 45 mg/kg of TAM for 10 days, whereas rats in the CAE-treated group were administered 10 mL/kg of CAE for 20 days, starting 10 days prior to TAM administration. Treatment with TAM resulted in severe degeneration of the pancreatic acini and marked increases in the serum levels of pancreatic lipase, α-amylase, glucose, fatty acids and triglycerides along with decreased insulin serum levels. TAM led to oxidative stress as evident from a significant increase in the pancreatic levels of lipid peroxides and nitric oxide along with the depletion of reduced glutathione, glutathione peroxidase, and superoxide dismutase. Moreover, inflammation was indicated by a significant increase in tumor necrosis factor-α and interleukin-6 levels, enhanced expression of the macrophage recruitment marker; CD68 as well as up-regulated protein levels of toll-like receptor 4 and nuclear factor kappa B and increased p-p38/MAPK ratio; which are important signals in the production of inflammatory cytokines. TAM also markedly increased the pancreatic levels of caspase-3 and BAX reflecting its apoptotic effects. The CAE treatment ameliorated all the biochemical and histological changes induced by TAM. The present study revealed, for the first time, that TAM has toxic effects on the pancreatic tissue through oxidative stress, inflammation and apoptotic effects. The present study also provides evidence that CAE exerts cytoprotective effects against these deleterious effects induced by TAM in the pancreatic tissue.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-023-00198-w.

Grape Seed Proanthocyanidins Improve the Quality of Fresh and Cryopreserved Semen in Bulls

Oxidative stress leads to a decrease in semen quality during semen cryopreservation and fresh semen production. Grape seed proanthocyanidins (GSPs) are endowed with well-recognized antioxidant, anti-inflammatory, anti-cancer, and anti-aging activities. Therefore, the objective of this experiment was to explore the effects of GSPs on the quality of fresh and cryopreserved semen to provide a basis for GSPs as a new dietary additive and semen diluent additive for males' reproduction. Fresh semen from three healthy bulls aged 3 to 5 years old were gathered and mixed with semen diluents dissolved with 0 µg/mL, 30 µg/mL, 40 µg/mL, 50 µg/mL, and 60 µg/mL GSPs respectively. The motility, physiological structures (acrosome integrity, membrane integrity, mitochondrial activity), and antioxidant capacity of frozen-thawed sperm were measured after storage in liquid nitrogen for 7 days (d). Bulls were fed with 20 mg/kg body weight (BW) GSPs in their diet for 60 days; the weight of the bull is about 600 kg. Then, the reproductive performance and antioxidant indexes of bulls were measured before and after feeding. The results demonstrated that GSPs supplementation significantly increased sperm motility, physiological structures, GSH-Px, and CAT enzyme activities and significantly decreased MDA content in sperm during semen cryopreservation. The optimal concentration of GSPs was 40 µg/mL (p < 0.05). After 20 mg/kg (body weight) GSP supplementation, sperm motility was significantly heightened (p < 0.05), the sperm deformity rate was significantly reduced (p < 0.05), and antioxidant enzyme activities (such as SOD, CAT, and GSH-Px) were significantly enhanced (p < 0.05), and the production of MDA was significantly suppressed (p < 0.05) in serum compared with that before feeding. In conclusion, these results reveal that a certain concentration of GSPs has a good protective effect on sperm damage caused by semen cryopreservation and the reproductive performance reduction caused by stress in bulls, which may be attributed to the antioxidant function of GSPs. In summary, GSPs are a useful cryoprotective adjuvant and dietary additive for bull sperm quality.

Dysfunctions, molecular mechanisms, and therapeutic strategies of pancreatic β-cells in diabetes

Pancreatic beta-cell death has been established as a critical mediator in the progression of type 1 and type 2 diabetes mellitus. Beta-cell death is associated with exacerbating hyperglycemia and insulin resistance and paves the way for the progression of DM and its complications. Apoptosis has been considered the primary mechanism of beta-cell death in diabetes. However, recent pieces of evidence have implicated the substantial involvement of several other novel modes of cell death, including autophagy, pyroptosis, necroptosis, and ferroptosis. These distinct mechanisms are characterized by their unique biochemical features and often precipitate damage through the induction of cellular stressors, including endoplasmic reticulum stress, oxidative stress, and inflammation. Experimental studies were identified from PubMed literature on different modes of beta cell death during the onset of diabetes mellitus. This review summarizes current knowledge on the crucial pathways implicated in pancreatic beta cell death. The article also focuses on applying natural compounds as potential treatment strategies in inhibiting these cell death pathways.

Beneficial effects of Chrysin on Cadmium-induced nephrotoxicity in rats: Modulating the levels of Nrf2/HO-1, RAGE/NLRP3, and Caspase-3/Bax/Bcl-2 signaling pathways

Cadmium (Cd) is a toxic heavy metal that targets the kidney directly in the body. Chrysin (CHR) is a natural flavonoid with many properties such as antioxidant, anti-inflammatory and anti-apoptotic. The current study discloses new evidence as regards of the curative effects of CHR on Cd-induced nephrotoxicity by regulating oxidative stress, apoptosis, autophagy, and inflammation. Cd was administered orally at a dose of 25 mg/kg body weight alone or in combination with orally administered CHR (25 and 50 mg/kg body weight) for 7 days. Biochemical, molecular, and histological methods were used to investigate inflammation, apoptosis, autophagy, and oxidant pathways in renal tissue. Renal function tests were also evaluated. Cd caused an increase in serum toxicity markers, lipid peroxidation and a decrease in the activities of antioxidant enzymes. Nrf-2 triggered inflammatory responses by suppressing HO-1 and NQO1 mRNA transcripts and increasing NF-κB, TNF-α, IL-1β and iNOS mRNA transcripts. Cd caused inflammasome by increasing RAGE and NLRP3 mRNA transcripts. In addition, Cd application caused apoptosis by increasing Bax, Apaf-1 and Caspase-3 mRNA transcripts and decreasing Bcl-2 mRNA transcript level. It caused autophagy by increasing the activity of Beclin-1 level. CHR treatment had the opposite effect on all these values and reduced the damage caused by all these signal pathways. Overall, the data of this study indicate that renal damage associated with Cd toxicity could be ameliorated by CHR administration.

Proanthocyanidins suppress NLRP3 inflammasome and M1 macrophage polarization to alleviate severe acute pancreatitis in mice

The role of reactive oxygen species (ROS) is crucial for the pathogenesis of acute pancreatitis (AP). Proanthocyanidins (PAs) have been confirmed to exert antioxidant activity. Our study aimed to determine whether PAs alleviated SAP via reducing ROS, suppressing NLRP3 inflammasome, and inhibiting M1 macrophage polarization. Our study investigated the protective effects of PAs on pancreatic histopathological injury using SAP mice. The effects of PAs on macrophages were investigated in inflammatory RAW 264.7 cells or mouse bone marrow-derived macrophages (BMDMs) induced by lipopolysaccharide (LPS). Immunofluorescence staining and/or western blot assay were employed to evaluate NLRP3 inflammasome in macrophages and pancreatic tissue. Cell counting kit-8 (CCK-8) was used to access effects of PAs on cell viability and cytometry flow was used to determine the effects of the PAs on the ROS levels of the RAW 264.7 cells. Then, we evaluated M1 macrophage polarization using flow cytometry or real-time quantitative polymerase chain reaction (RT-qPCR). PAs administration alleviated pancreatic inflammation in SAP mice. The PAs depressed NLRP3 inflammasome and inhibited M1 macrophage polarization in pancreatic tissue. We also found that the PAs showed no cellular toxicity but decreased ROS levels in RAW 264.7 cells, downregulated the NLRP3 inflammasome in the macrophages, and inhibited cell M1 macrophage polarization. Our study indicates the anti-inflammatory properties of the PAs on SAP mice by decreasing ROS levels, suppressing NLRP3 inflammasome, and M1 macrophage polarization.

Protective effect of dendropanoxide against cadmium-induced hepatotoxicity via anti-inflammatory activities in Sprague-Dawley rats

Cadmium (Cd) accumulates in the body through contaminated foods or water and causes pathological damage to the liver via oxidative stress and inflammatory reactions. This study was conducted to explore the effects of dendropanoxide (DPx) on Cd-induced hepatotoxicity in rats. Sprague-Dawley (SD) rats were injected with CdCl2 (7 mg/kg body weight) intraperitoneally for 14 days for the induction of liver dysfunction. The CdCl2-exposed rats were subjected to DPx (10 mg/kg) or silymarin (50 mg/kg). The animals were euthanized after 24 h of the last CdCl2 injection and the serum biochemical parameters, lipid content, pro-inflammatory cytokine levels, apoptotic cell death and histopathology of the tissues were analyzed. Additionally, the activity of antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT), was measured. Compared to controls, Cd-injected rats showed significantly elevated serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglycerides (TG), total cholesterol, and pro-inflammatory cytokines, and a remarkable decrease in SOD and CAT activities. Importantly, Cd-induced liver damage was drastically ameliorated by treatment with DPx or silymarin. Treatment with DPx protected the Cd-induced histopathological hepatic injury, as confirmed by the evaluation of TUNEL assay. DPx treatment significantly reduced Bax and caspase-3 expression in Cd-injected rats. Additionally, HO-1 and NRF2 expressions were significantly increased after DPx administration in the liver of Cd-injected rats. Our data indicate that DPx successfully prevents Cd-induced hepatotoxicity by emphasizing the antioxidant and anti-inflammatory effect.

Advances in the Bioactivities of Phytochemical Saponins in the Prevention and Treatment of Atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease characterized by hardening and narrowing of arteries. AS leads to a number of arteriosclerotic vascular diseases including cardiovascular diseases, cerebrovascular disease and peripheral artery disease, which pose a big threat to human health. Phytochemicals are a variety of intermediate or terminal low molecular weight secondary metabolites produced during plant energy metabolism. Phytochemicals from plant foods (vegetables, fruits, whole grains) and traditional herb plants have been shown to exhibit multiple bioactivities which are beneficial for prevention and treatment against AS. Many types of phytochemicals including polyphenols, saponins, carotenoids, terpenoids, organic sulfur compounds, phytoestrogens, phytic acids and plant sterols have already been identified, among which saponins are a family of glycosidic compounds consisting of a hydrophobic aglycone (sapogenin) linked to hydrophilic sugar moieties. In recent years, studies have shown that saponins exhibit a number of biological activities such as anti-inflammation, anti-oxidation, cholesterol-lowering, immunomodulation, anti-platelet aggregation, etc., which are helpful in the prevention and treatment of AS. This review aims to summarize the recent advances in the anti-atherosclerotic bioactivities of saponins such as ginsenoside, soyasaponin, astra-galoside, glycyrrhizin, gypenoside, dioscin, saikosaponin, etc.

Curative Potential of Substances with Bioactive Properties to Alleviate Cd Toxicity: A Review

Rapid urbanization and industrialization have led to alarming cadmium (Cd) pollution. Cd is a toxic heavy metal without any known physiological function in the organism, leading to severe health threat to the population. Cd has a long half-life (10-30 years) and thus it represents serious concern as it to a great extent accumulates in organs or organelles where it often causes irreversible damage. Moreover, Cd contamination might further lead to certain carcinogenic and non-carcinogenic health risks. Therefore, its negative effect on population health has to be minimalized. As Cd is able to enter the body through the air, water, soil, and food chain one possible way to defend and eliminate Cd toxicities is via dietary supplements that aim to eliminate the adverse effects of Cd to the organism. Naturally occurring bioactive compounds in food or medicinal plants with beneficial, mostly antioxidant, anti-inflammatory, anti-aging, or anti-tumorigenesis impact on the organism, have been described to mitigate the negative effect of various contaminants and pollutants, including Cd. This study summarizes the curative effect of recently studied bioactive substances and mineral elements capable to alleviate the negative impact of Cd on various model systems, supposing that not only the Cd-derived health threat can be reduced, but also prevention and control of Cd toxicity and elimination of Cd contamination can be achieved in the future.

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.

Protective Effects of Grape Seed Proanthocyanidin Extract in Preventing DSS Induced Ulcerative Colitis Based on Pharmacodynamic, Pharmacokinetic and Tissue Distribution

BACKGROUND

Based on pharmacodynamic, pharmacokinetic and tissue distribution studies, we explored the potential effect of grape seed proanthocyanidin extract (GSPE) on dextran sodium sulfate (DSS) -induced ulcerative colitis in mice and its underlying mechanism.

METHODS

A liquid chromatography-mass spectrometry method was developed to measure the content of five components of GSPE in rat plasma and tissue. After oral administration of GSPE, correlative index levels of interleukin-1β (IL-1β), interleukin-6 (IL-6), factor-α (TNF-α), Nitric Oxide (NO), malonaldehyde (MDA), and superoxide dismutase (SOD) were detected in the serum and colon tissues. The protein expression levels of HO-1, Nrf2 and NF-κB in the mouse colonic mucosa were analysed using immunohistochemistry.

RESULTS

Pharmacodynamic tests showed substantially reduced mice body weight, diarrhea, and bloody stool in the model group. The pathological damage to the colonic mucosa of mice in the GSPE groups was remarkably reduced in a dose-dependent manner. The histopathological score of the colon in the model group was significantly higher than that of the control group (P <0.05), suggesting that DSS caused severe damage to the colon. After oral administration of GSPE, the serum and colonic tissue levels of IL-1β, IL-6, TNF-α, NO, and MDA decreased, whereas SOD content increased, Moreover, the protein levels of NF-κB and Keap-1 were significantly decreased, whereas the expression levels of Nrf2 and HO-1 proteins increased (P＜0.01) based on the results of the microwave-immunohistochemical assay. The pharmacokinetic results showed that catechin, epicatechin, and procyanidins B1, B2, and B4 are widely distributed in the tissues and blood of rats and may accumulate in some tissues. Catechin and epicatechin peaked at 0.25 and 1.5 h for the first and second time, respectively. Procyanidin B1, B2, and B4 peaked at 0.5 and 1.5 h for the first and second time, respectively, owing to the effect of the hepato-enteric circulation. The active components of GSPE can reach the colon of the lesion site, and hepatoenteric circulation can increase the residence time of the active components in the body, which further increases the anti-ulcer activity.

CONCLUSION

Our findings suggest that GSPE has a potential protective effect against DSS-induced ulcerative colitis in mice.

Ellagic acid inhibits proinflammatory intermediary manufacture by suppressing NF-κB/Akt, VEGF and activating Nrf-2/Caspase-3 signaling pathways in rat testicular damage: a new way for testicular damage cure and in silico approach

Ellagic acid (EA) has protective effect on testicular damage and this natural compound decreases oxidative damage. The present study aims to examine the preventive effect of ellagic acid (EA) against carbon tetrachloride (CCl₄)-induced testicular tissue damage in rats. In testicular tissue, tumor necrosis factor-α (TNF-α), Nuclear factor erythroid-2 related factor 2 (Nrf-2), B-cell lymphoma-2 (Bcl-2), vascular endothelial growth factor (VEGF), Nuclear factor-kappa B (NF-κB), cysteine aspartic proteases (caspase-3) and protein kinase B (Akt) synthesis levels were analyzed by western blot method, reactive oxygen species (ROS) was measured by malondialdehyde (MDA) levels, Glutathione (GSH) level and catalase (CAT) by spectrophotometer. As a result, in comparison with the CCl₄ group, caspase-3 and Nrf-2 protein synthesis levels increased in EA + CCl₄ group, however, VEGF, Bcl-2, NF-κB, TNF-α and Akt protein synthesis levels decreased, EA application raised GSH levels and CAT activity, reduced MDA levels. In this study, in silico tools were applied to confirm the activity of EA against the cancer with macromolecules such as the above mentioned transcription factors. EA, turned out to show significant activity similarly to some cocrystal ligands, particularly against cancer. These results points out that EA can be used as a testicular damage cure drug in future.

Improvement of Glucose Tolerance by Food Factors Having Glucagon-Like Peptide-1 Releasing Activity

Glucagon-like peptide-1 (GLP-1) is a gastrointestinal hormone released from enteroendocrine L cells in response to meal ingestion. GLP-1 receptor agonists and GLP-1 enhancers have been clinically employed to treat diabetes owing to their glucose-dependent insulin-releasing activity. The release of GLP-1 is primarily stimulated by macronutrients such as glucose and fatty acids, which are nutritionally indispensable; however, excessive intake of sugar and fat is responsible for the development of obesity and diabetes. Therefore, GLP-1 releasing food factors, such as dietary peptides and non-nutrients, are deemed desirable for improving glucose tolerance. Human and animal studies have revealed that dietary proteins/peptides have a potent effect on stimulating GLP-1 secretion. Studies in enteroendocrine cell models have shown that dietary peptides, amino acids, and phytochemicals, such as quercetin, can directly stimulate GLP-1 secretion. In our animal experiments, these food factors improved glucose metabolism and increased GLP-1 secretion. Furthermore, some dietary peptides not only stimulated GLP-1 secretion but also reduced plasma peptidase activity, which is responsible for GLP-1 inactivation. Herein, we review the relationship between GLP-1 and food factors, especially dietary peptides and flavonoids. Accordingly, utilization of food factors with GLP-1-releasing/enhancing activity is a promising strategy for preventing and treating obesity and diabetes.

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

AIM

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

MATERIALS AND METHODS

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

KEY FINDINGS

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

SIGNIFICANCE

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

Scutellarin ameliorates high glucose-induced vascular endothelial cells injury by activating PINK1/Parkin-mediated mitophagy

ETHNOPHARMACOLOGICAL RELEVANCE

Scutellarin (Scu) is one of the main active ingredients of Erigeron breviscapus (Vant.) Hand.-Mazz which has been used to treat cardiovascular disease including vascular dysfunction caused by diabetes. Scu also has a protective effect on vascular endothelial cells against hyperglycemia. However, molecular mechanisms underlying this effect are not clear.

AIM OF THE STUDY

This aim of this study was to investigate the effect of Scu on human umbilical vein endothelial cells (HUVECs) injury induced by high glucose (HG), especially the regulation of PTEN-induced kinase 1 (PINK1)/Parkin-mediated mitophagy.

MATERIALS AND METHODS

HUVECs were exposed to HG to induce vascular endothelial cells injury in vitro. Cell viability was assessed by MTT assay. The extent of cell apoptosis was measured by Hoechst staining and flow cytometry. Mitophagy was assayed by fluorescent immunostaining, transmission electron microscope and immunoblot. Besides, virtual docking was conducted to validate the interaction of PINK1 protein and Scu.

RESULTS

We found that Scu significantly increased cell viability in HG-treated HUVECs. Scu reduces the expression of Bcl-2, Bax and cytochrome C (Cyt.c) to inhibit apoptosis through a mitochondria-dependent pathway. Meanwhile, Scu improved the overload of reactive oxygen species (ROS), superoxide dismutase (SOD) activity and SOD2 protein expression, and reversed the collapse of mitochondrial membrane potential. Besides, Scu increased autophagic flux, improved the expression of microtubule-associated protein 1 light chain 3 Ⅱ (LC3 II), Beclin 1 and autophagy-related gene 5 (Atg 5) and decreased the expression of Sequestosome1/P62 in HG-treated HUVECs. Furthermore, Scu improved the expressions of PINK1, Parkin, and Mitofusin2, which revealed the enhancement of mitophagy. Moreover, the beneficial effects of Scu on HG-induced low expression of Parkin, overproduction of ROS, and over expressions of P62, Cyt.c and Cleaved caspase-3 were weakened by PINK1 gene knockdown. Molecular docking suggested good interaction of Scu and PINK1 protein.

CONCLUSION

These results suggest that Scu may protect vascular endothelial cells against hyperglycemia-induced injury by up-regulating mitophagy via PINK1/Parkin signal pathway.

Cadmium induces endoplasmic reticulum stress-mediated apoptosis in pig pancreas via the increase of Th1 cells

Cadmium (Cd), an environmental pollutant, causes several adverse reactions in animals. High dose of Cd has serious cytotoxicities, including the induction of programmed cell necrosis, autophagy and apoptosis, which has aroused wide public concern. The balance of cytokine network is affected by Th1/Th2 balance which is closely related to immune response and the occurrence, development, treatment and outcome of various diseases. Cd can induce severe apoptosis, but the relationship between Cd induced apoptosis and Th1/Th2 balance has not been clarified. In this study, we established a pig Cd poisoning model, exposing to CdCl₂ for 40 days (20 mg Cd/kg diet). Firstly, deviation of Th1/Th2 balance was observed by fluorescence staining, and apoptosis was observed by TUNEL staining. Then, real-time fluorescence quantitative analysis and Western blot were used to detect the expression of related proteins. The results show that Cd can interfere with the balance of Th1/Th2 and shift the balance towards Th1. In addition, through the experiments, we found that Cd exposure can increase the expression of glucose-regulated protein 94 (GRP94) and glucose-regulated protein 78 (GRP78), marker proteins of unfolded protein response (UPR). Cd exposure can increase the expression of pancreatic endoplasmic reticulum kinase (PERK), CCAAT-enhancer-binding protein homologous protein (CHOP), inositol-requiring enzyme 1 (IRE-1), activating transcription factor 6 (ATF-6), cysteinyl aspartate specific proteinase (Caspase12), indicating the three branches (ATF6, PERK and IRE-1) of endoplasmic reticulum stress (ER-stress) were activated. Moreover, we found that the expression of pro-apoptosis genes in the downstream pathway of ER-stress increased. In summary, our results indicated that Cd exposure upregulated the expression of pro-apoptosis related genes and caused apoptosis via the activation of the ER-stress signaling pathways in pancreas cells. And these negative effects were correlated with the equilibrium drift of Th1/Th2, increase in the expression and secretion of Th1 cytokines.

The impact of ellagic acid on some apoptotic gene expressions: a new perspective for the regulation of pancreatic Nrf-2/NF-κB and Akt/VEGF signaling in CCl4-induced pancreas damage in rats

OBJECTIVE

The aim of this study was to evaluate the potential effect of ellagic acid (EA) in the treatment of pancreatic injury. EA has been found to have strong anti-inflammatory, antioxidative, and anticancer properties. The effects of EA on pancreati˜c star cell (PSC) activation and cell functions have been evaluated and it has been shown that it inhibits the activation of basic cell functions and PSCs and^. it has antidiabetic activity through its effect on β-pancreas cells.

MATERIALS AND METHODS

In this work, 36 Wistar albino rats (n = 36, 8 weeks old) were used. Rats were divided to 4 groups and 9 rats were each group. Groups: Group 1: control group; Group 2: EA group; Group 3: carbon tetrachloride (CCl₄) group; Group 4: EA + CCl₄ group. Animals were decapitated after 8 weeks and their pancreas tissue samples were taken and researched. In pancreas tissue, NF-κB, TNF-α, Nrf-2, VEGF, Bcl-2, caspase-3, and Akt proteins expression ratios were analyzed by western blotting method, CAT activity and GSH levels were determined by spectrophotometer and ROS production was detected by MDA.

RESULTS

In our results, the Nrf-2 and caspase-3 protein expressions, catalase activities and GSH levels increased, TNF-α, NF-κB, Bcl-2, VEGF, and Akt protein expressions and MDA levels reduced in EA + CCl₄ group comparable to the CCl₄ group.

CONCLUSIONS

These findings reveal that EA decreases pancreas tissue injury in rats and that EA may also be used as a drug against pancreas tissue injury in the future.

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.

Simulated gastrointestinal digestion of Brazilian açaí seeds affects the content of flavan-3-ol derivatives, and their antioxidant and anti-inflammatory activities

Açaí seeds (Euterpe oleracea Mart.) are the major residue generated during industrial extraction of açaí fruit pulp - a popular and typical Amazon fruit rich in bioactive compounds and nutrients. In this study, we investigated the bioaccessibility of an açaí seed extract using an in vitro simulated gastrointestinal digestion model. Catechin, epicatechin and procyanidins B1 and B2 were identified and quantified in the açaí seed extract and monitored by HPLC-DAD through the digestion phases. Bioaccessibility of these flavan-3-ols and deactivation of reactive oxygen species decreased after the intestinal phase, except for peroxyl radical (ROO^●). RAW 264.7 macrophages treated either with the digested or undigested açaí seed extract showed reduced NF-κB activation and TNF-α levels, even following gastrointestinal digestion. Thus, the ROO^● scavenging capacity and anti-inflammatory activity of the extract were found to be still remarkable after digestion, suggesting that açaí seeds could be explored as a source of bioactive compounds for functional foods, cosmetic or pharmaceutical purposes.

Hesperidin ameliorates hepatic dysfunction and dyslipidemia in male Wistar rats exposed to cadmium chloride

The ever-increasing human population with attendant industrialization poses serious global health challenge. Cadmium (Cd) with other heavy metals contribute greatly to environmental pollutions and humans are daily exposed to them, leading to diverse ailments. We explored whether Hesperidin (HSP) could protect against hepatic damage and dyslipidemia in Wistar rats exposed to Cd. Forty wistar rats were randomly assigned into five groups (n = 8). Group 1 received 2 mL/kg body weight of normal saline; Group 2 received 100 mg/kg body weight of HSP while Group 3 received 5 mg/kg body weight of Cadmium Chloride (CdCl2) for 28 days. Group 4 received 100 mg/kg body weight of HSP and after 90 min, CdCl2 (5 mg/kg) body weight was administered for 28 days. Group 5 received 50 mg/kg body weight of HSP and after 90 min, CdCl2 (5 mg/kg) body weight was administered for 28 days. The serum lipid profiles, hepatic dysfunction and oxidative stress markers were determined using standard methods. Cd toxicity in rats prominently elevated serum activities of AST, ALT, ALP and levels of total bilirubin, direct bilirubin, cholesterol, LDL-C and malondialdehyde with decreased levels of HDL-C, triglycerides, superoxide dismutase, catalase, glutathione and body weights. The pre-treatment of HSP before Cd intoxication prevented the dysregulated activities of liver enzymes and levels of lipid profiles, enzymatic and non-enzymatic antioxidants and other biomarkers investigated, thus suggesting anti-hyperlipidemic and hepato-protective potentials. HSP may have great potentials for development of therapeutics that could enhance the management of dyslipidemia and liver disorders associated with heavy metal exposure.

Ellagic acid prevents kidney injury and oxidative damage via regulation of Nrf-2/NF-κB signaling in carbon tetrachloride induced rats

Phytochemicals, bioactive food compounds, found in plants have been described as protective agents against renal injury. This work was planned to evaluate the effects of EA on anti-oxidative and anti-inflammation pathways in kidney damage induced with carbon tetrachloride. In this study, experimental animals (n = 36, 8 weeks old rats) were divided into 4 groups as follows: 1) Control group 2) EA group (10 mg/kg body weight) 3) CCl₄ group (1.5 ml/kg, body weight) 4) EA + CCl₄ group. The potentially protective effect of EA on kidney damage exposed by CCl₄ in rats were evaluated. EA administration protects CCl₄ induced kidney damage against oxidative stress through its antioxidant protection. Treatment of EA significantly reduced lipid peroxidation and improved glutathione and catalase enzyme activity. Recently studies showed that EA activated caspase-3 and nuclear transcription factor erythroid 2 related factor driven antioxidant signal pathway and protected the kidney against damage induced by oxidative stress. Furthermore, EA also markedly decreased the level of cyclooxygenase-2, the vascular endothelial growth factor and tumor necrosis factor-alpha and suppressed the protein synthesis of nuclear factor-kappa-B. This study reveals that EA has kidney protective effect against CCl₄ induced oxidative damage and inflammation.

Emerging Links between Cadmium Exposure and Insulin Resistance: Human, Animal, and Cell Study Data

Recent research has helped clarify the role of cadmium (Cd) in various pathological states. We have demonstrated Cd involvement in pancreatic cancer, as well as the bioaccumulation of Cd in the pancreas. Bioaccumulation and increased toxicity suggest that Cd may also be involved in other pancreas-mediated diseases, like diabetes. Cd falls into the category of "hyperglycemic" metals, i.e., metals that increase blood glucose levels, which could be due to increased gluconeogenesis, damage to β-cells leading to reduced insulin production, or insulin resistance at target tissue resulting in a lack of glucose uptake. This review addresses the current evidence for the role of Cd, leading to insulin resistance from human, animal, and in vitro studies. Available data have shown that Cd may affect normal insulin function through multiple pathways. There is evidence that Cd exposure results in the perturbation of the enzymes and modulatory proteins involved in insulin signal transduction at the target tissue and mutations of the insulin receptor. Cd, through well-described mechanisms of oxidative stress, inflammation, and mitochondrial damage, may also alter insulin production in β-cells. More work is necessary to elucidate the mechanisms associated with Cd-mediated insulin resistance.

Protective Effect of Grape and Apple Juices against Cadmium Intoxication in the Kidney of Rats

BACKGROUND

The objective of this study was to evaluate protective effect of grape and apple juices against toxicity induced by cadmium in the kidney of rats.

METHODS

A total of 20 male-Wistar rats were distributed into four groups (n=5): Control group: animals received an intraperitoneal (i.p.) injection of 0.9% saline solution and after 15 days, 1 mL of water was administered for 15 days, via gavage; Cadmium group: animals received an intraperitoneal injection of cadmium chloride (1.2 mg/kg) and after 15 days, 1 mL of water was administered for 15 days via gavage; Cadmium+Grape Juice: animals received an i.p. injection of cadmium chloride (1.2 mg/kg), and after 15 days, 0.8 mL of grape juice was administered for 15 days, via gavage; Cadmium+Apple Juice: animals received i.p. injection of cadmium chloride (1.2 mg/kg) and after 15 days, 1.0 mL of apple juice was administered for 15 days, via gavage.

RESULTS

Histopathological analysis revealed severe tubular lesion and necrosis in the group exposed to cadmium, while animals exposed to grape or apple juices showed a significant reduction of tissue injury. 8-OHdG immunoexpression, DNA damage, cytochrome C and catalase gene expressions and Toll like signaling pathway (TLR2, and pIKKα/β) decreased in animals treated with grape juice when compared to cadmium group.

CONCLUSION

Taken together, we conclude that grape and apple juices had a protective effect by means of antioxidant, antigenotoxic actions and for promoting tissue regeneration in the kidney of rats following cadmium intoxication.

Hesperidin protects against cadmium-induced pancreatitis by modulating insulin secretion, redox imbalance and iNOS/NF-ĸB signaling in rats

AIM

Cadmium is a persistent ubiquitous environmental toxicant that elicits several biological defects on delicate body organs. Growing evidence suggests that cadmium (Cd) may perturb signaling pathways to induce oxidative pancreatitis. Thus, we explored whether hesperidin, a flavonone, could mitigate Cd-induced oxidative stress-mediated inflammation and pancreatitis in Wistar rats.

MAIN METHODS

Forty (40) rats randomly assigned to 5 groups (n = 8) were administered normal saline or hesperidin (Hsp) followed by Cd intoxication for 28 days.

KEY FINDINGS

Cadmium accumulated in the pancreas of rats, and markedly decreased insulin, pancreatic superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and glutathione (GSH) level. Cadmium considerably increased malondialdehyde (MDA), serum lipase and amylase activities. Cadmium induced pancreatic pro-inflammation via over-expression of inducible nitric oxide synthase (iNOS), nuclear factor-ĸB (NF-κB), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), along with histopathological alterations. Hesperidin prominently decreased serum amylase and lipase activities, and markedly increased insulin level, pancreatic antioxidant defense mechanism, whereas iNOS, NF-κB, IL-6 and TNF-α levels significantly decreased. Changes in histology confirmed our biochemical findings.

SIGNIFICANCE

Our findings suggest that Cd induced pancreatitis via pro-inflammation and oxidative stress; Hsp, thus, protects against Cd-induced pancreatitis via attenuation of oxidative stress and proinflammatory responses in pancreas.

Stevia rebaudiana extract attenuate metabolic disorders in diabetic rats via modulation of glucose transport and antioxidant signaling pathways and aquaporin-2 expression in two extrahepatic tissues

Today, plant-based therapies have been attracted attention to overcome diabetes complications. This study was an attempt to evaluate whether antidiabetic and nephroprotective effects of Stevia Rebaudiana Bertoni (SRB) can be exerted via upregulation of GLUT-4, SNAP23, and Stx4 in skeletal muscles or modulation of AQP2 mRNA expression and antioxidant signaling pathway activity (Nrf2/Keap1) in kidneys. To achieve this aim, diabetes was induced via STZ-nicotinamide (STZ-NA). Diabetes increased the level of Blood Urea Nitrogen (BUN), serum creatinine, Fasting Blood Sugar (FBS), and Keap1 mRNA expression, which was coincide with reduction in mRNA levels of Nrf2, GLUT4, SNAP23, and Stx4. SRB and metformin compensate mentioned variables. However, SRB extract was more effective than metformin to increase the levels of GLUT4 and Nrf2 mRNA. It seems that SRB might attenuate the diabetic complications via manipulating the glucose uptake components in peripheral tissues and might exert the nephroprotective effects by modulation of AQP2, and Nrf2/Keap1 mRNA expression. PRACTICAL APPLICATIONS: Synthetic antidiabetic drugs have been only partially successful in controlling the diabetic complications. Moreover, use of these drugs is associated with a number of adverse effects. Over the past few years, a renewed attention has been paid to the prevention and treatment of diabetes using medicinal plants and functional foods. SRB that have been known as natural sweetener for centuries, is a such natural agent that has high source of various phytochemicals with antidiabetic, renal protective, antitumor, and antioxidant properties. In the current study, possible molecular mechanisms of insulin-mimetic and nephroprotective effects of SRB extract was evaluated in diabetic rats. Due to powerful antihyperglycemic and nephroprotective effects of SRB extract that were showed in this study and previous studies, hence the fact that SRB is to be highlighted for future research as a new therapeutic agent for diabetes.

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.

The Role of Natural Antioxidants Against Reactive Oxygen Species Produced by Cadmium Toxicity: A Review

Cadmium (Cd) is a significant ecotoxic heavy metal that adversely affects all biological processes of humans, animals and plants. Exposure to acute and chronic Cd damages many organs in humans and animals (e.g. lung, liver, brain, kidney, and testes). In humans, the Cd concentration at birth is zero, but because the biological half-life is long (about 30 years in humans), the concentration increases with age. The industrial developments of the last century have significantly increased the use of this metal. Especially in developing countries, this consumption is higher. Oxidative stress is the imbalance between antioxidants and oxidants. Cd increases reactive oxygen species (ROS) production and causes oxidative stress. Excess cellular levels of ROS cause damage to proteins, nucleic acids, lipids, membranes and organelles. This damage has been associated with various diseases. These include cancer, hypertension, ischemia/perfusion, cardiovascular diseases, chronic obstructive pulmonary disease, diabetes, insulin resistance, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, asthma, skin diseases, chronic kidney disease, eye diseases, neurodegenerative diseases (amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and Huntington disease). Natural antioxidants are popular drugs that are used by the majority of people and have few side effects. Natural antioxidants play an important role in reducing free radicals caused by Cd toxicity. Our goal in this review is to establish the relationship between Cd and oxidative stress and to discuss the role of natural antioxidants in reducing Cd toxicity.

Supplementation of by-products from grape, tomato and myrtle affects antioxidant status of dairy ewes and milk fatty acid profile

The aim of this study was to evaluate the effect of diets containing different dried by-products on milk and blood plasma antioxidant capacity of dairy ewes. Thirty-six Sarda ewes were assigned to four treatments: control (CON; no by-product), 100 g/day of grape marc (GM), 100 g/day tomato pomace (TP) and 75 g/day of exhausted myrtle berries (EMBs). The superoxide dismutase (SOD), glutathione reductase (GR), glutathione transferase (GST) and glutathione peroxidase (GSH-Px) in blood, and SOD, GR and lactoperoxidase (LPO) in milk were determined. Total antioxidant capacity (FRAP and ABTS assays), malondialdehyde (MDA) and protein carbonyls (PCs) were also measured. Milk fatty acid profile was investigated by gas chromatography. The results showed higher antioxidant capacity measured by FRAP or ABTS assays and a reduction in MDA in GM plasma than CON. All by-products enhanced the protection of milk proteins by oxidation, as evidenced by lower values of PCs compared with CON. GM supplementation increased PUFAn-6, due to increase in C18:2n-6, the main component of GM compared with CON. All by-products did not modify the nutritional indexes of milk fat. In conclusion, dietary GM may enhance protection against oxidative condition of dairy ewes, whereas TP and EMB need further research to define the optimum inclusion level in sheep diet.

Novel flavan-3-ol-glutathione conjugates from the degradation of proanthocyanidins as highly bioactive antioxidants

Synthesis, preparation and antioxidant capacity evaluation of flavan-3-ol-glutathione conjugates.

Cadmium exposure triggers mitochondrial dysfunction and oxidative stress in chicken (Gallus gallus) kidney via mitochondrial UPR inhibition and Nrf2-mediated antioxidant defense activation

Cadmium (Cd) is a widespread environmental pollutant that accumulates in living systems and represents a significant global health hazard. Cd poses a toxicity threat to both human and animal health, including that of birds. Further knowledge of Cd toxicology pathways will allow for a better understanding of Cd-induced nephrotoxicity. To evaluate Cd-induced nephrotoxicity through potential oxidative damage, male chickens were treated with 0 mg/kg, 35 mg/kg or 70 mg/kg CdCl₂ in diet for 90 days. Markedly, histopathology indicated renal tubular epithelial cell swelling, renal function CREA content abnormalities, biochemical and morphologic indices indicative of Cd-induced kidney injury. Cd toxicity induced the up-regulation of Nrf2 and downstream target genes that relieve oxidative stress. Meanwhile, Cd disrupted the homeostasis of trace elements and promoted oxidative damage. Cd interfered with mitochondrial unfolded protein response (UPR^mt)-related factors (SIRT1, SIRT3, PGC-1α, TFAM, Nrf1, and HTRA2) and disrupted the homeostasis of mitochondrial dynamics (OPA1, MFN1, MFN2, Fis1 and MFF), thereby exacerbating mitochondrial structural damage and mitochondrial dysfunction. In conclusion, our study demonstrated that the nephrotoxicity of Cd exposure results in oxidative stress and mitochondrial dysfunction by activating the Nrf2 signaling pathway and inhibiting UPR^mt in the kidneys.

Environmental cadmium exposure and pancreatic cancer: Evidence from case control, animal and in vitro studies

Although profoundly studied, etiology of pancreatic cancer (PC) is still rather scarce. Some of established risk factors of PC are connected to an increased cadmium (Cd) body burden. Hence, the aim of this study was to investigate the role of this environmental pollutant in PC development by conducting human observational, experimental and in vitro studies. The case-control study included 31 patients with a histologically based diagnosis of exocrine PC subjected to radical surgical intervention as cases and 29 accidental fatalities or subjects who died of a nonmalignant illness as controls. Animal study included two treated groups of Wistar rats (15 and 30 mg Cd/kg b.w) and untreated control group, sacrificed 24 h after single oral exposure. In in vitro study pancreas hTERT-HPNE and AsPC-1 cells were exposed to different Cd concentrations corresponding to levels measured in human cancerous pancreatic tissue. Cd content in cancer tissue significantly differed from the content in healthy controls. Odds ratio levels for PC development were 2.79 (95% CI 0.91-8.50) and 3.44 (95% CI 1.19-9.95) in the third and fourth quartiles of Cd distribution, respectively. Animal study confirmed Cd deposition in pancreatic tissue. In vitro studies revealed that Cd produces disturbances in intrinsic pathway of apoptotic activity and the elevation in oxidative stress in pancreatic cells. This study presents three different lines of evidence pointing towards Cd as an agent responsible for the development of PC.

Grape seed proanthocyanidins and metformin combination attenuate hepatic endoplasmic reticulum stress in rats subjected to nutrition excess

CONTEXT

Endoplasmic reticulum (ER) stress in the liver is a pathological outcome of nutrient excess and is suggested to be one of the hits for progressive liver injury.

OBJECTIVE

This study investigated whether grape seed proanthocyanidins (GSP) and metformin (MET) alone or in combination can relieve hepatic ER stress induced in rats subjected to calorie excess.

MATERIAL AND METHODS

Male albino Wistar rats were given high calorie diet (HCD) for 45 days, while GSP (100 mg/kg body weight) and MET (50 mg/kg body weight) were administered either alone or in combination for last 15 days.

RESULTS

GSP, MET or both had reduced the levels of ER stress markers and chaperons, and suppressed the activation of lipogenic and inflammatory mediators in rat liver.

DISCUSSION

Though GSP and MET had reduced ER stress and inflammation individually, combination treatment with GSP + MET was more effective.

CONCLUSION

We suggest intervention with GSP and MET intake has to be considered for the management of liver disorders.

Flavonoids for preserving pancreatic beta cell survival and function: A mechanistic review

Although the currently available antidiabetic medications are effective in managing hyperglycemia, vascular complications are common in diabetic patients. Cohort studies have shown preserved beta cell function has a protective role against the development of diabetic complications. Accordingly, beta cell mass and function are important pharmacological targets in the field of diabetes. Growing number of evidence supports the efficacy of flavonoids (e.g., quercetin, kaempferol, luteolin, and epicatechin) for prevention and attenuation of diabetes consequences. The focus of this paper is to give an overview regarding the effects of flavonoids on pancreatic beta cells. Experiments on insulin-releasing cell lines, isolated pancreatic islets, and diabetic animal models have shown that flavonoids strengthen the survival processes and insulin secretory capacity of beta cells. The proposed mechanisms by which flavonoids preserve beta cells survival (against cytokines, glucotoxicity, and lipotoxicity) include inhibition of NF-κB signaling, activation of PI3K/Akt pathway, inhibition of nitric oxide generation, and decrease of reactive oxygen species levels. Improving mitochondrial bioenergetic function and stimulating pathways of insulin secretion (e.g., PLC/PKC and/or cAMP/PKA signaling) are mechanisms by which flavonoids improve the secretory capacity of beta cells. These beneficial effects of flavonoids are of great importance because may protect beta cells of diabetic patients before dramatic dysfunction and degeneration.

Sulforaphane Protect Against Cadmium-Induced Oxidative Damage in mouse Leydigs Cells by Activating Nrf2/ARE Signaling Pathway

Cadmium (Cd) is harmful for humans and animals, especially for the reproductive system. However, the mechanism of its toxicity has not been elucidated, and how to alleviate its toxicity is very important. This study aimed to explore the role and mechanism of action of sulforaphane (SFN) in protecting mouse Leydigs (TM3) cells from cadmium (Cd)-induced damage. The half-maximal inhibitory concentration (IC₅₀) of Cd and the safe doses of SFN were determined using a methyl thiazolyl tetrazolium (MTT) assay. The testosterone secretion from TM3 cells was measured using the enzyme-linked immunosorbent assay. The intracellular oxidative stress was evaluated using corresponding kits. The cell apoptosis was detected using flow cytometry. The mRNA expression of genes associated with NF-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) signaling was detected using reverse transcription–polymerase chain reaction, including Nrf2, heme oxygenase I (HO-1), glutathione peroxidase (GSH-Px), NAD(P)H:quinone acceptor oxidoreductase 1 (NQO1), and γ-glutamylcysteine synthetase (γ-GCS). The protein expression of Nrf2, GSH-Px, HO-1, γ-GCS, and NQO1 was detected using Western blot analysis. The results showed that the IC₅₀ of Cd to TM3 cells was 51.4 µmol/L. SFN reduced the release of lactate dehydrogenase from Cd-exposed cells. Cd + SFN 2.5 treatment significantly elevated testosterone concentration compared with the Cd group (p < 0.05). SFN significantly increased total superoxide dismutase (T-SOD) and GSH-Px activity and GSH content in Cd-treated cells (p < 0.05; p < 0.01), inhibited the production of malondialdehyde or reactive oxygen species caused by Cd (p < 0.05; p < 0.01), and reduced the apoptotic rate of Cd-induced TM3 cells (p < 0.01). SFN upregulated the mRNA expression of Nrf2, GSH-Px, HO-1, NQO1, and γ-GCS in Cd-treated cells, indicating the protective effect of SFN against Cd-induced oxidative stress or cell apoptosis by activating the Nrf2/ARE signaling pathway.

The effect of oxidative stress upon intestinal sugar transport: an in vitro study using human intestinal epithelial (Caco-2) cells

The pathogenesis of various gastrointestinal diseases, including gastrointestinal cancers and inflammatory bowel disease, is associated with increased oxidative stress levels. We aimed to investigate the effect of oxidative stress induced by tert-butylhydroperoxide (TBH) on the uptake of 3H-deoxy-d-glucose (3H-DG) and 14C-fructose by the human intestinal Caco-2 cell line. TBH (500 μM; 24 h) increased lipid peroxidation (TBARS) levels and was not cytotoxic. TBH (500 μM; 24 h) increased uptake of both low (SGLT1-mediated) and high concentrations (SGLT1- and GLUT2-mediated) of 3H-DG, but did not affect absorption of 14C-fructose (GLUT2- and GLUT5-mediated). The polyphenol chrysin abolished the increase in TBARS levels and the increase in uptake of both low and high concentrations of 3H-DG induced by TBH. On the other hand, TBH blocked the inhibitory effect of chrysin on 14C-fructose uptake. 3H-DG uptake, but not 14C-fructose uptake, was sensitive to sweet taste receptor (STRs) inhibition (with lactisole). The inhibitory effect of lactisole in relation to uptake of 3H-DG (10 nM) (SGLT1-mediated), but not in relation to uptake of 3H-DG (50 mM) (SGLT1- and GLUT2-mediated), was abolished in the presence of TBH. So, these results show that the stimulatory effect of STRs on SGLT1-mediated transport is dependent on oxidative stress levels. In conclusion, this work shows that uptake of both 3H-DG and 14C-fructose is sensitive to oxidative stress levels. Moreover, it suggests that the three distinct transporters involved in the intestinal absorption of glucose and fructose (SGLT1, GLUT2 and GLUT5) have different sensitivities to oxidative stress levels, SGLT1 being the most sensitive and GLUT5 the least.

Protective Mechanism of Sulforaphane on Cadmium-Induced Sertoli Cell Injury in Mice Testis via Nrf2/ARE Signaling Pathway

The present study evaluated the mechanism underlying the protective effect of sulforaphane (SFN) on cadmium (Cd)-induced Sertoli cell (TM4 cells) injury in mice. The apoptosis rate of cells in each group was detected by flow cytometry. It was determined the effect of SFN on the expression of downstream molecular targets of Nrf2/ARE axis and on the lipid peroxide content. The related genes involved in the nuclear factor E2-related factor 2(Nrf2)/antioxidant response element (ARE) signaling pathway were evaluated by RT-PCR; for example, the mRNA expression levels of Nrf2, heme oxygenase-1 (HO-1), glutathione peroxidase (GSH-Px), quinone oxidoreductase 1 (NQO1), and γ-glutamylcysteine synthetase (γ-GCS), while the protein expression levels were assessed by Western blot. Our results showed that the mRNA and protein expression levels of Nrf2, HO-1, NQO1, GSH-Px, and γ-GCS were increased in various degree when the Sertoli cells were to added different concentrations of SFN. Our results also showed that SFN reduced the apoptosis rate, increased the activity of T-SOD, inhibited the increase of the MDA content caused by Cd. Meanwhile, SFN could increase the mRNA and protein expression levels of Nrf2, HO-1 and NQO1 and reduced the mRNA and protein expression levels of GSH-Px and γ-GCS caused by Cd in Sertoli cells (p < 0.01). Taken together, SFN could improve the antioxidant capacity of Sertoli cells, and exert a protective effect on the oxidative damage and apoptosis of Cd-induced Sertoli cells through the activation of Nrf2/ARE signal transduction pathway.

Naringenin Protects against Acute Pancreatitis in Two Experimental Models in Mice by NLRP3 and Nrf2/HO-1 Pathways

Background

Naringenin (Nar) is a type of flavonoid and has been shown to have anti-inflammatory and antioxidative properties. However, the effects of Nar on acute pancreatitis (AP) have not been well studied. In this study, we aimed to investigate the function of Nar in a mouse model of AP.

Methods

Mild acute pancreatitis (MAP) was induced by caerulein (Cae), and severe acute pancreatitis (SAP) was induced by L-arginine in mice. Nar was administered intraperitoneally at doses of 25, 50, or 100 mg/kg following MAP induction and at a dose of 100 mg/kg following SAP induction. The serum levels of cytokines, lipase, and amylase were determined, and pancreatic and pulmonary tissues were harvested.

Results

The serum levels of amylase, lipase, and cytokines were significantly decreased in both MAP and SAP models after Nar treatment. The malondialdehyde (MDA) levels of the pancreatic tissue was significantly reduced in both MAP and SAP after Nar treatment. In contrast, glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), total sulfhydryl (T-SH), and non-proteinsulthydryl (NP-SH) were markedly increased in both MAP and SAP after Nar treatment. The injury in pancreatic and pulmonary tissues was markedly improved as evidenced by the inhibited expression of myeloperoxidase, nod-like receptor protein 3, and interleukin 1 beta as well as the enhanced expression of nuclear factor erythroid 2-related factor 2/heme oxygenase-1 in pancreatic tissues.

Conclusions

Nar exerted protective effects on Cae-induced MAP and L-arginine-induced SAP in mice, suggesting that Nar may be a potential therapeutic intervention for AP.

Phytoceuticals in Acute Pancreatitis: Targeting the Balance between Apoptosis and Necrosis

Despite recent advances in understanding the complex pathogenesis of pancreatitis, the management of the disease remains suboptimal. The use of phytoceuticals (plant-derived pleiotropic multitarget molecules) represents a new research trend in pancreatology. The purpose of this review is to discuss the phytoceuticals with pancreatoprotective potential in acute pancreatitis and whose efficacy is based, at least in part, on their capacity to modulate the acinar cell death. The phytochemicals selected, belonging to such diverse classes as polyphenols, flavonoids, lignans, anthraquinones, sesquiterpene lactones, nitriles, and alkaloids, target the balance between apoptosis and necrosis. Activation of apoptosis via various mechanisms (e.g., inhibition of X-linked inhibitor of apoptosis proteins by embelin, upregulation of FasL gene expression by resveratrol) and/or inhibition of necrosis seem to represent the essential key for decreasing the severity of the disease. Apart from targeting the apoptosis/necrosis balance, the phytochemicals displayed other specific protective activities: inhibition of inflammasome (e.g., rutin), suppression of neutrophil infiltration (e.g., ligustrazine, resveratrol), and antioxidant activity. Even though many of the selected phytoceuticals represent a promising therapeutic alternative, there is a shortage of human evidence, and further studies are required to provide solid basis to justify their use in the treatment of pancreatitis.