Protective effect of Vitamin D3 against lead induced hepatotoxicity, oxidative stress, immunosuppressive and calcium homeostasis disorders in rat

Lead-induced liver fibrosis and inflammation in mice by the AMPK/MAPKs/NF-κB and STAT3/TGF-β1/Smad2/3 pathways: the role of Isochlorogenic acid a

Lead (Pb) is a nonessential heavy metal, which can cause many health problems. Isochlorogenic acid A (ICAA), a phenolic acid present in tea, fruits, vegetables, coffee, plant-based food products, and various medicinal plants, exerts multiple effects, including anti-oxidant, antiviral, anti-inflammatory and antifibrotic functions. Thus, the purpose of our study was to determine if ICAA could prevent Pb-induced hepatotoxicity in ICR mice. An evaluation was performed on oxidative stress, inflammation and fibrosis, and related signaling. The results indicate that ICAA attenuates Pb-induced abnormal liver function. ICAA reduced liver fibrosis, inflammation and oxidative stress caused by Pb. ICAA abated Pb-induced fibrosis and decreased inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-alpha (TNF-α). ICAA abrogated reductions in activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Masson staining revealed that ICAA reduced collagen fiber deposition in Pb-induced fibrotic livers. Western blot and immunohistochemistry analyses showed ICAA increased phosphorylated AMP-activated protein kinase (p-AMPK) expression. ICAA also reduced the expression of collagen I, α-smooth muscle actin (α-SMA), phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated c-jun N-terminal kinase (p-JNK), p-p38, phosphorylated signal transducer and phosphorylated activator of transcription 3 (p-STAT3), transforming growth factor β1 (TGF-β1), and p-Smad2/3 in livers of mice. Overall, ICAA ameliorates Pb-induced hepatitis and fibrosis by inhibiting the AMPK/MAPKs/NF-κB and STAT3/TGF-β1/Smad2/3 pathways.

Protective Effects of Dietary Vitamin D3, Turmeric Powder, and Their Combination against Gasoline Intoxication in Rats

The inhalation of gasoline vapors (GV) is associated with developing various pathologies. Particularly, oil refinery and gas station workers are at a greater risk of developing lung cancer, kidney cancer, bladder cancer, and hematological disorders, including acute myeloid leukemia. Therefore, preventing the harmful effects of GV and alleviating their consequences appear to be important and timely issues. In this study, we investigated the potential of vitamin D3, turmeric powder, and their combination to ameliorate the toxicity of gasoline fumes in rats. Separate groups of animals fed with a standard rodent diet, with or without the supplementation of vitamin D3 (750 IU/kg body weight) and/or turmeric powder (0.5%, w/w, in food), were untreated or treated with GV (11.5 ± 1.3 cm3/h/m3/day) for 30, 60, or 90 days. Changes in the body weight were monitored weekly. Histological, biochemical, and hematological parameters were determined at the end of each treatment period. While the exposure of rats to GV resulted in a time-dependent reduction in body weight, supplementation with vitamin D3, but not with turmeric root powder or their combination, partially prevented weight loss. Macroscopical and histological analyses showed pronounced time-dependent changes in the organs and tissues of GV-treated rats. These included alveolar wall collapse in the lungs, the destruction of the lobular structure and hepatocytolysis in the liver, the shrinkage and fragmentation of glomeruli in the kidneys, and the disorganization of the lymphoid follicles in the spleen. However, co-treatment with the nutritional supplements tested, especially vitamin D3, noticeably alleviated the above conditions. This was accompanied by a significant improvement in the blood chemistry and hematological parameters. Collectively, our results demonstrate that the harmful effects of environmental exposure to GV can be reduced upon supplementation of vitamin D3. The fact that the protective activity of vitamin D3 alone was higher than that of turmeric root powder or the combined treatment suggests that combinations of these supplements may not always be more beneficial than each agent applied separately.

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.

Heavy Metal Exposure: Molecular Pathways, Clinical Implications, and Protective Strategies

Heavy metals are often found in soil and can contaminate drinking water, posing a serious threat to human health. Molecular pathways and curation therapies for mitigating heavy metal toxicity have been studied for a long time. Recent studies on oxidative stress and aging have shown that the molecular foundation of cellular damage caused by heavy metals, namely, apoptosis, endoplasmic reticulum stress, and mitochondrial stress, share the same pathways as those involved in cellular senescence and aging. In recent aging studies, many types of heavy metal exposures have been used in both cellular and animal aging models. Chelation therapy is a traditional treatment for heavy metal toxicity. However, recently, various antioxidants have been found to be effective in treating heavy metal-induced damage, shifting the research focus to investigating the interplay between antioxidants and heavy metals. In this review, we introduce the molecular basis of heavy metal-induced cellular damage and its relationship with aging, summarize its clinical implications, and discuss antioxidants and other agents with protective effects against heavy metal damage.

Endoplasmic reticulum stress associated with lead (Pb)-induced olfactory epithelium toxicity in an olfactory dark basal cell line

Lead (Pb) can damage organs and also have undesirable effects on neural development. To explore the effects of Pb on olfactory cells, we investigated Pb-induced cell toxicity in the DBC1.2 olfactory cell line, with a focus on endoplasmic reticulum (ER) stress, apoptosis, and necroptosis. Representative markers of ER stress, apoptosis, and necroptosis were analyzed by quantitative PCR. The mRNA expression levels of GRP94, GRP78, spliced XBP1, PERK, and ATF6 increased significantly after Pb exposure in a dose-dependent manner. The expression of Caspase 3 and Caspase 12 did not increase after Pb exposure, which suggested that apoptosis-induced cell death was not activated after Pb exposure. However, the mRNA of RIPK3 and MLKL showed increases in expression, which indicated that necroptosis-induced cell death was activated after Pb exposure. These results indicate that Pb exposure induced dose-dependent cytotoxicity through ER stress and necroptosis pathways in DBC1.2 cells, whereas the apoptosis pathway was not significantly stimulated. HEPES buffer showed a partial protective effect in terms of ER stress, apoptosis, and necroptosis. In summary, the necroptosis pathway plays a crucial rule in Pb exposure-induced cytotoxicity in olfactory cells.

Association between female circulating heavy metal concentration and abortion: a systematic review and meta-analysis

Objective

This study aimed to evaluate the association between blood heavy metal (zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd)) concentrations and spontaneous abortion (SA) and recurrent pregnancy loss (RPL) and explore the possible endocrine dysfunction associated with it.

Methods

A literature search was performed in the PubMed, Embase, Cochrane Library, and Web of Science databases up to April 2023. The overall effects were expressed as the standard mean difference (SMD). Subgroup analysis was performed according to the type of abortion (SA or RPL). Stata 16.0 was utilized for data analysis.

Results

Based on the integrated findings, abortion women showed significantly lower Zn (SMD = -1.05, 95% CI: -1.74 to -0.36, p = 0.003) and Cu concentrations (SMD = -1.42, 95% CI: -1.97 to -0.87, p <0.001) and higher Pb (SMD = 1.47, 95% CI: 0.89-2.05, p <0.001) and Cd concentrations (SMD = 1.15, 95% CI: 0.45-1.85, p = 0.001) than normal pregnant women. Subgroup analysis showed that Zn and Cu deficiency and Cd and Pb exposure were significantly (p <0.05) associated with RPL, whereas Cu deficiency and Cd and Pb exposure were significantly (p <0.05) associated with SA.

Conclusion

Zn and Cu deficiencies and Pb and Cd exposure were associated with abortion. Endocrine dysfunction, such as insulin resistance, vitamin D insufficiency, and abnormal thyroid and sex hormone concentrations, is thought to be involved in heavy metal-related abortion.

Effects of the Vitamin D3 on Alleviating the Oxidative Stress Induced by Diquat in Wenchang Chickens

Vitamin D₃ (VD₃) is an indispensable micronutrient in livestock and poultry feed. Its function in antioxidant stress has been reported. We investigate whether the addition of different concentrations of VD₃ to the diet affects the production performance, slaughter performance, meat quality, organ index, and gut injury on the diquat (DQ)-induced model of oxidative stress in Wenchang chickens. Four hundred and eighty one-day-old chickens were randomly divided into six groups: control (basal diet), 4000 VD (basal diet + VD₃ 4000 IU per kg feed intake), 1000 VD+DI (DQ, basal diet + VD₃ 1000 IU per kg feed intake), 2000 VD+DI (DQ, basal diet + VD₃ 2000 IU per kg feed intake), and 4000 VD+DI (DQ, basal diet + VD₃ 4000 IU per kg feed intake). The results showed that the addition of VD₃ to the diet promoted DQ-induced weight loss and reduced ADFI, slaughter rate, splenic index, and pH after 1 h and 24 h in the leg muscles. VD₃ decreased the increase in content of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) among proinflammatory cytokines (p < 0.05) and increased the reduction in anti-inflammatory cytokines content of interleukin-10 (IL-10) (p < 0.05) induced by DQ. In addition, liver and kidney injury biomarkers and the intestinal permeability index in serum were disordered after treatment with DQ (p < 0.05). VD₃ perfected the increase of D-lactic acid (D-LA), diamine oxidase (DAO), total cholesterol (T-CHO), creatinine (CR), blood urea nitrogen (BUN), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) content, aspartate transaminase (AST), alanine transaminase (ALT), and lactate dehydrogenase (LDH) activity (p < 0.05); it increased the decrease of albumin (ALB) content (p < 0.05). Meanwhile, VD₃ regulated the intestinal morphology and intestinal barrier. Moreover, DQ induced a decrease in total antioxidant capacity and antioxidant enzyme activity in the serum, liver, and jejunum (p < 0.05), and an increase in malonaldehyde (MDA) content (p < 0.05). However, the addition of different levels of VD₃ could alleviate the above phenomenon of oxidative stress in Wenchang chickens to different degrees. Thus, this research suggested that the addition of VD₃ can relieve the DQ-induced oxidative stress of Wenchang chickens, and the level of VD₃ acquisition is positively correlated with the remission effect.

Vitamin D Ameliorates the Hepatic Oxidative Damage and Fibrotic Effect Caused by Thioacetamide in Rats

Vitamin D₃ (VD₃) is a sunshine hormone that regulates cellular proliferation, differentiation, apoptosis, and angiogenesis related to liver parenchyma. We used a thioacetamide (TAA)-induced hepatic fibrosis rat model in our study to investigate the beneficial roles of VD₃ to overcome extensive liver fibrosis. Randomly, four equal groups (eight rats per group) underwent therapy for eight successive weeks: a control group, a group treated with TAA 100 mg/kg BW IP every other day, a group treated with VD₃ 1000 IU/kg BW IM every day, and a TAA+VD group treated with both therapies. Treatment with VD₃ after TAA-induced hepatic fibrosis was found to alleviate elevated liver function measures by decreasing ALT, AST, and ALP activity; decreasing total bilirubin, direct bilirubin, cholesterol, and triglyceride levels; and increasing glucose and 25[OH]D₃. Rats treated with VD₃ showed marked decreases in MDA and increased SOD, CAT, and GSH levels. In addition, CD34 and FGF23 gene expressions were reduced after dual therapy. Liver sections from the TAA+VD group showed markedly decreased hepatic lesions, and Masson's trichrome stain showed a marked decrease in dense bluish-stained fibrous tissue. The immunohistochemical expression of TGF-β and α-SMA showed markedly decreased positive brown cytoplasmic expression in a few hepatocytes, clarifying the antifibrotic effect of VD₃ in hepatic fibrosis. In conclusion, VD₃ alleviates hepatotoxicity and fibrosis caused by TAA.

Protective effects of sinomenine hydrochloride on lead-induced oxidative stress, inflammation, and apoptosis in mouse liver

Lead, one of the most common heavy metal toxins, seriously affects the health of humans and animals. Sinomenine hydrochloride (SH) shows antioxidative, anti-inflammatory, antiviral, and anticancer properties. Hence, this study investigated the protective effects of SH against Pb-induced liver injury and explored the underlying mechanisms. First, a mouse model of lead acetate (0.5 g/L lead acetate in water, 8 weeks) was established, and SH (100 mg/kg bw in water, 8 weeks) intervention was administered by gavage. Then, the protective effect of SH against lead-induced liver injury was evaluated through serum biochemical analysis, histopathological analysis, and determination of malondialdehyde (MDA) and total antioxidant capacity (T-AOC) levels. The messenger RNA (mRNA) expression levels of the cytokines IL-1β and TNF-α and the apoptosis factors Bax, Bcl-2, and Caspase3 in the liver were detected by quantitative real-time PCR. Then, the expression levels of IL-1β and TNF-α in the liver were detected by ELISA. Immunohistochemical determination of the expression of the apoptosis factors Bax, Bcl-2, and Caspase3 was performed. SH treatment reduced the levels of liver alanine aminotransferase, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and MDA in Pb-treated mice, indicating that SH protected the liver from injury and oxidative stress in Pb-treated mice. SH also increased the liver T-AOC of Pb-treated mice. Quantitative real-time PCR, ELISA, and immunohistochemical analysis showed that SH inhibited apoptosis, as indicated by the regulation of the mRNA expression of Bax and Bcl-2 and the reduced expression of Caspase3 and pro-inflammatory factors (IL-1β and TNF-α) in the livers of Pb-treated mice. These results suggest that SH protects the mouse liver from Pb-induced injury. The underlying mechanism involves antioxidative, anti-inflammatory, and anti-apoptotic processes.

Deferasirox and vitamin D3 co-therapy mitigates iron-induced renal injury by enhanced modulation of cellular anti-inflammatory, anti-oxidative stress, and iron regulatory pathways in rat

BACKGROUND

Chronic iron overload could induce nephropathy via oxidative stress and inflammation, and chelating therapy has limited efficacy in removing excess intracellular iron. Although vitamin D (VD) has shown potent antioxidant and anti-inflammatory effects, as well contribute to iron homeostasis, none of the previous studies measured its potential remedial effects against chronic iron toxicity.

AIMS

To measure the alleviating effects of deferasirox (DFX) and/or vitamin D (VD) single and combined therapies against nephrotoxicity induced by chronic iron overload.

METHODS

Forty male rats were divided into negative (NC) and positive (PC) controls, DFX, VD, and DFX/VD groups. The designated groups received iron for six weeks followed by DFX and/or VD for another six weeks. Then, the expression pattern of renal genes and proteins including hepcidin, ferroportin (FPN), megalin, transferrin receptor 1 (TfR1), ferritin heavy and light chains, VD receptor (VDR), VD synthesizing (Cyp27b1) and catabolizing (Cyp24a1) enzymes were measured alongside serum markers of renal function and iron biochemical parameters. Additionally, several markers of oxidative stress (MDA/H₂O₂/GSH/SOD1/CAT/GPx4) and inflammation (IL-1β/IL-6/TNF-α/IL-10) together with renal cell apoptosis and expression of caspase-3 (Casp-3) were measured.

RESULTS

The PC rats showed pathological iron and renal biochemical markers, hypovitaminosis D, increased renal tissue iron contents with increased Cyp24a1/Megalin/ferritin-chains/hepcidin, and decreased Cyp27b1/VDR/TfR1/FPN expression than the NC group. The PC renal tissues also showed abnormal histology, increased inflammatory (IL-1β/IL-6/TNF-α), oxidative stress (MDA/H₂O₂), and apoptosis markers with decreased IL-10/GSH/SOD1/CAT/GPx4. Although DFX monotherapy reduced serum iron levels, it was comparable to the PC group in renal iron concentrations, VD and iron-homeostatic molecules, alongside markers of oxidative stress, inflammation, and apoptosis. On the other hand, VD monotherapy markedly modulated renal iron and VD-related molecules, reduced renal tissue iron concentrations, and preserved renal tissue relative to the PC and DFX groups. However, serum iron levels were equal in the VD and PC groups. In contrast, the best significant improvements in serum and renal iron levels, expression of renal iron-homeostatic molecules, oxidative stress, inflammation, and apoptosis were seen in the co-therapy group.

CONCLUSIONS

iron-induced nephrotoxicity was associated with dysregulations in renal VD-system together with renal oxidative stress, inflammation, and apoptosis. While DFX reduced systemic iron, VD monotherapy showed better attenuation of renal iron concentrations and tissue damage. Nonetheless, the co-therapy approach exhibited the maximal remedial effects, possibly by enhanced modulation of renal iron-homeostatic molecules alongside reducing systemic iron levels.

AVAILABILITY OF DATA AND MATERIALS

All data generated or analysed during this study are included in this published article [and its Supplementary information files].

Elucidating the Differences in Metal Toxicity by Quantitative Adverse Outcome Pathways

Numerous studies have reported that the toxicity differences among metals are widespread; however, little is known about the mechanism of differences in metal toxicity to aquatic organisms due to the lack of quantitative understanding of their adverse outcome pathway. Here, we investigated the effects of Cd and Cu on bioaccumulation, gene expression, physiological responses, and apical effects in zebrafish larvae. RNA sequencing was conducted to provide supplementary mechanistic information for the effects of Cd and Cu exposure. On this basis, we proposed a quantitative adverse outcome pathway (qAOP) suitable for metal risk assessment of aquatic organisms. Our work provides a mechanistic explanation for the differences in metal toxicity where the strong bioaccumulation of Cu enables the newly accumulated Cu to reach the threshold that causes different adverse effects faster than Cd in zebrafish larvae, resulting in a higher toxicity of Cu than that of Cd. Furthermore, we proposed a parameter C_IT/BCF (the ratio of internal threshold concentration and bioaccumulation factor) that helps to understand the toxicity differences by combining the information of bioaccumulation and internal threshold of adverse effects. This work demonstrated that qAOP is an effective quantitative tool for understanding the toxicity mechanism and highlight the importance of toxicokinetics and toxicodynamics at different biological levels in determining the metal toxicity.

Relationship between Body Composition and Biochemical Parameters with Antioxidant Status in a Healthy Cohort of Postmenopausal Women

An adequate prooxidant–antioxidant balance—which may be influenced by body composition and biochemical status—is essential to maintain human health, especially in circumstances under which the antioxidant defense decreases, such as menopause. The present study aimed to examine the relationship between body composition and biochemical parameters with antioxidant status in a healthy cohort of postmenopausal women. This cross-sectional study was carried out in a cohort of 78 postmenopausal women aged 44–76 years. The body composition profile was assessed through bioelectrical impedance. The determination of the total antioxidant capacity and superoxide dismutase activity was conducted by the colorimetric method, and glutathione peroxidase activity was determined by the enzymatic immunological method. The vitamin D levels were measured by ultra-performance liquid chromatography–tandem mass spectrometry. The mineral status was assessed through flame atomic absorption spectrophotometry. The rest of the biochemical parameters were assessed through an immunoassay. The total antioxidant capacity and antioxidant gap were negatively influenced by body composition (all p ≤ 0.049) and positively related to protein metabolism parameters (all p ≤ 0.048), whereas circulating levels of different micronutrients (all p ≤ 0.048) and enzymes (all p ≤ 0.047) appeared to play an important role in the glutathione peroxidase and superoxide dismutase activities. In conclusion, the menopause-related antioxidant status changes may be influenced by key body composition and biochemical profiles. To confirm this statement, further trials aiming to evaluate the body composition and biochemical intervention-induced changes upon antioxidant defense are needed.

Mitochondrial calcium uniporter involved in foodborne mycotoxin-induced hepatotoxicity

Foodborne mycotoxins are toxic metabolites that are produced by fungi. The widespread contamination of food and its by-products by mycotoxins is a global food safety problem that potentially threatens public health and other exposed animals. Most foodborne mycotoxins induce hepatotoxicity. However, only few studies have investigated the regulatory mechanisms of mitochondrial calcium transport monomers in mycotoxin-induced hepatotoxicity. Therefore, according to relevant studies and reports, this review suggests that intracellular Ca(2 +) homeostasis and mitochondrial Ca(2 +) uniporter are involved in the regulation of mycotoxin-induced hepatotoxicity. This review provides some ideas for future research involving mitochondrial Ca(2 +) uniporter in the molecular targets of mycotoxin-induced hepatotoxicity, as well as a reference for the research and development of related drugs and the treatment of related diseases.

Potential ameliorative effect of dietary quercetin against lead-induced oxidative stress, biochemical changes, and apoptosis in laying Japanese quails

Lead (Pb) is a widespread environmental pollutant which is a toxic threat to human and animal health. The present study was designed to evaluate the ameliorative role of quercetin in laying quails exposed to Pb. A total of 112 birds were randomly divided into four groups. The control group was fed with basal diet, the Pb group was fed with ration supplemented with Pb at the dose of 100 mg/kg (as Pb (II) acetate trihydrate), the Quercetin group was fed with ration supplemented with quercetin at the dose of 400 mg/kg, and the Pb+ Quercetin group was fed with ration supplemented with Pb at the dose of 100 mg/kg and quercetin at dose of 400 mg/kg. Results showed that serum total protein, glucose, albumin, and blood urea nitrogen (BUN) values of the Pb + Quercetin group partially improved with quercetin supplementation. Meanwhile, serum creatinine values of the Pb + Quercetin group was found to be significantly lower than that of the Pb group. Aspartate aminotransferase (AST) and alanine transaminase (ALT) enzyme activities in the Quercetin and Pb + Quercetin groups were similar to those of the Control group, unlike the Pb group. Moreover, alkaline phosphatase (ALP) enzyme activity of the Pb + Quercetin group significantly improved with the addition of quercetin. We also found that malondialdehyde (MDA) levels of the kidney, liver, and heart were significantly reduced by quercetin supplementation. The glutathione, catalase, and glutathione peroxidase activities of the kidney, liver, and heart tissue were increased by quercetin supplementation. These results were in line with the observed apoptotic markers. The expression of caspase-3 and caspase-9 were significantly decreased by quercetin supplementation. It may be concluded that dietary supplementation with quercetin ameliorates the toxic effects of Pb exposure by alleviating oxidative stress, biochemical changes, and apoptosis in quails.

Co-Inhibition of P-gp and Hsp90 by an Isatin-Derived Compound Contributes to the Increase of the Chemosensitivity of MCF7/ADR-Resistant Cells to Doxorubicin

Breast cancer is a complex and multi-drug resistant (MDR) disease, which could result in the failure of many chemotherapeutic clinical agents. Discovering effective molecules from natural products or by derivatization from known compounds is the interest of many research studies. The first objective of the present study is to investigate the cytotoxic combinatorial, chemosensitizing, and apoptotic effects of an isatin derived compound (5,5-diphenylimidazolidine-2,4-dione conjugated with 5-substituted isatin, named HAA₂₀₂₁ in the present study) against breast cancer cells (MCF7) and breast cancer cells resistant to doxorubicin (MCF7/ADR) when combined with doxorubicin. The second objective is to investigate the binding mode of HAA₂₀₂₁ withP-glycoprotein (P-gp) and heat shock protein 90 (Hsp90), and to determine whether their co-inhibition by HAA₂₀₂₁ contribute to the increase of the chemosensitization of MCF7/ADR cells to doxorubicin. The combination of HAA₂₀₂₁, at non-toxic doses, with doxorubicin synergistically inhibited the proliferation while inducing significant apoptosis in MCF7 cells. Moreover, HAA₂₀₂₁ increased the chemosensitization of MCF7/ADR cells to doxorubicin, resulting in increased cytotoxicity/selectivity and apoptosis-inducing efficiency compared with the effect of doxorubicin or HAA₂₀₂₁ alone against MCF7/ADR cells. Molecular modeling showed that two molecules of HAA₂₀₂₁ bind to P-gp at the same time, causing P-gp inhibitory effect of the MDR efflux pump, and accumulation of Rhodamine-123 (Rho123) in MCF7/ADR cells. Furthermore, HAA₂₀₂₁ stably interacted with Hsp90α more efficiently compared with 17-N-allylamino-17-demethoxygeldanamycin (17-AAG), which was confirmed with the surface plasmon resonance (SPR) and molecular modeling studies. Additionally, HAA₂₀₂₁ showed multi-target effects via the inhibition of Hsp90 and nuclear factor kappa B (NF-𝜅B) proteins in MCF7 and MCF7/ADR cells. Results of real time-PCR also confirmed the synergistic co-inhibition of P-gp/Hsp90α genes in MCF7/ADR cells. Further pharmacokinetic and in vivo studies are warranted for HAA₂₀₂₁ to confirm its anticancer capabilities.

Plant Polyphenols: Potential Antidotes for Lead Exposure

Lead is one of the most common heavy metal elements and has high biological toxicity. Long-term lead exposure will induce the contamination of animal feed, water, and food, which can cause chronic lead poisoning including nephrotoxicity, hepatotoxicity, neurotoxicity, and reproductive toxicity in humans and animals. In the past few decades, lead has caused widespread concern because of its significant threat to health. A large number of in vitro and animal experiments have shown that oxidative stress plays a key role in lead toxicity, and endoplasmic reticulum (ER) stress and the mitochondrial apoptosis pathway can also be induced by lead toxicity. Therefore, plant polyphenols have attracted attention, with their advantages of being natural antioxidants and having low toxicity. Plant polyphenols can resist lead toxicity by chelating lead with their special chemical molecular structure. In addition, scavenging active oxygen and improving the level of antioxidant enzymes, anti-inflammatory, and anti-apoptosis are also the key to relieving lead poisoning by plant polyphenols. Various plant polyphenols have been suggested to be useful in alleviating lead toxicity in animals and humans and are believed to have good application prospects.

Vitamin D3 protects against lead-induced testicular toxicity by modulating Nrf2 and NF-κB genes expression in rat

Lead (Pb) is an environmental toxin that has the ability to alter biological processes by inducing oxidative stress (OS) and inflammation. Nuclear factor erythroid 2-related factor 2 (Nrf2) and nuclear factor-kappa B (NF-κB) are two transcriptional factors that participate in the regulation of cellular responses against OS and inflammation. This study was conducted to evaluate the effects of vitamin D3 (VD) on the prevention of testicular damages of Pb and its association with Nrf2 and NF-κB gene expression levels and their downstream molecules. Forty male Wistar rats were divided into four groups and treatments were performed as following for four weeks: control group received no treatment, VD group were injected intramuscularly with 1000 IU of VD/Kg every other day, Pb group received 1000 mg of Pb/L of drinking water, and Pb + VD group were exposed to Pb and VD simultaneously. The results demonstrated significant decrease in the levels of tissue antioxidants, and increase in inflammatory cytokines in the Pb-intoxicated group, with increased Nrf2 and NF-κB mRNA levels. A remarkable reduction in sperm criteria and a significant disruption in serum hormones were also observed. Anyhow, VD supplementation during exposure to Pb showed a significant protective effect against all pathophysiologic alterations caused by Pb. Furthermore, VD affected the expression of Nrf2 and NF-κB and mitigated the harsh effects of Pb. In conclusion, our findings indicate that VD attenuated the toxic impacts of Pb on testis through modulation of Nrf2 and NF-κB gene expression levels which further regulated the OS and inflammatory responses.

Effects of vitamin D supplementation on blood markers in ulcerative colitis patients: a systematic review and meta-analysis

OBJECTIVE

Observational studies have shown that vitamin D levels are inversely related to ulcerative colitis activity, yet evidence from population interventions remains inconsistent. We conducted a systematic review and meta-analysis of randomized-controlled trials to clarify the effect of vitamin D on blood markers in patients with ulcerative colitis.

METHODS

The PubMed, Cochrane Library, Embase, CNKI, VIP, and Wanfang databases were searched for studies published before June 2020. Information was collected regarding serum vitamin D levels, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP), and Ca (calcium), and parathyroid hormone (PTH), and ulcerative colitis disease activity index (UCDAI) research data.

RESULTS

Seven studies (n = 539) were included in the meta-analysis. Vitamin D supplementation resulted in significant improvements in the serum vitamin D levels (standardized mean difference (SMD) = 0.69, 95% CI (0.36, 1.03), P < 0.001), ESR (weighted mean difference (WMD) = - 1.10, 95% CI (- 1.97, - 0.24), P = 0.01), CRP (SMD = - 0.43, 95% CI (- 0.67, - 0.20), P = 0.0003), and Ca (SMD = 0.92, 95% CI (0.09, 1.74), P = 0.03) but not in other outcomes. According to subgroup analysis, supplementation with vitamin D at a dose of ≥ 300,000 IU/day can improve serum vitamin D levels. Supplementation with a sufficient dose of vitamin D in a short period of time can also improve serum vitamin D levels. According to GRADE method evaluation, the evidence quality was classified as low for the Serum Vitamin D Level and ESR, and very low for the CRP, PTH, Ca, and UCDAI.

CONCLUSIONS

Compared with placebo control interventions, vitamin D supplementation seemed to be an effective intervention for patients with ulcerative colitis. Different doses of vitamin D and durations of intervention produce different effects. However, due to the limitation of the quality of the included studies, the above conclusions still need to be verified by more high-quality studies and weak clinical recommendations.

Molecular mechanism of heavy metals (Lead, Chromium, Arsenic, Mercury, Nickel and Cadmium) - induced hepatotoxicity - A review

Heavy metals pose a serious threat if they go beyond permissible limits in our bodies. Much heavy metal's viz. Lead, Chromium, Arsenic, Mercury, Nickel, and Cadmium pose a serious threat when they go beyond permissible limits and cause hepatotoxicity. They cause the generation of ROS which in turn causes numerous injuries and undesirable changes in the liver. Epidemiological studies have shown an increase in the levels of such heavy metals in the environment posing a serious threat to human health. Epigenetic alterations have been seen in the event of exposure to such heavy metals. Apoptosis, caspase activation as well as ultrastructural changes in the hepatocytes have also been seen due to heavy metals. Inflammation involving TNF-alpha, pro-inflammatory cytokines, MAPK, ERK pathways have been seen in the event of heavy metal hepatotoxicity. All these have shown that these heavy metals pose a serious threat to human health in particular and the environment as a whole.

Association between cumulative childhood blood lead exposure and hepatic steatosis in young Mexican adults

BACKGROUND

Exposure to environmental toxicants may play a role in the pathogenesis of Non Alcoholic Fatty Liver Disease (NAFLD). Cumulative exposure to lead (Pb) has chronic and permanent effects on liver function. Pediatric populations are vulnerable to the toxic effects of Pb, even at low exposure levels. The purpose of the study was to estimate the association between cumulative Pb exposure during childhood and hepatic steatosis biomarkers in young Mexican adults.

METHODS

A subsample of 93 participants from the ELEMENT cohort were included in this study. Childhood blood samples were collected annually from ages 1-4 years and were used to calculate the Cumulative Childhood Blood Lead Levels (CCBLL). Hepatic steatosis during adulthood was defined as an excessive accumulation of hepatic triglycerides (>5%) determined using Magnetic Resonance Imaging (MRI). Liver enzymes were also measured at this time, and elevated liver enzyme levels were defined as ALT (≥30 IU/L), AST (≥30 IU/L), and GGT (≥40 IU/L). Adjusted linear regression models were fit to examine the association between CCBLL (quartiles) and the hepatic steatosis in young adulthood.

RESULTS

In adulthood, the mean age was 21.4 years, 55% were male. The overall prevalence of hepatic steatosis by MRI was 19%. Elevate levels of the enzymes ALT, AST, and GGT were present in 25%, 15%, and 17% of the sample, respectively. We found a positive association between the highest quartile of CCBLL with the steatosis biomarkers of hepatic triglycerides (Q4 vs. Q1: β = 6.07, 95% CI: 1.91-10.21), elevated ALT (Q4 vs. Q1: β = 14.5, 95% CI: 1.39-27.61) and elevated AST (Q4 vs. Q1: β = 7.23, 95% CI: 0.64-13.82). No significant associations were found with GGT.

CONCLUSIONS

Chronic Pb exposure during early childhood is associated with a higher levels of hepatic steatosis biomarkers and hepatocellular injury in young adulthood. More actions should be taken to eliminate sources of Pb during the first years of life.

Cadmium exposure induces TNF-α-mediated necroptosis via FPR2/TGF-β/NF-κB pathway in swine myocardium

Cadmium (Cd) is one common environmental pollutant with systemic toxicity. Lipoxin A4 (LXA4) can regulate transforming growth factor-β (TGF-β) pathway and alleviate tissue injury via binding to formyl peptide receptor 2 (FPR2). The activation of nuclear factor-κB (NF-κB) pathway can promote the occurence of necroptosis. However, whether Cd exposure induces necroptosis in swine myocardium and the role of FPR2/TGF-β/NF-κB pathway in this process are unclear. Hence, we established Cd-exposed swine myocardial injury model by feeding a CdCl₂ added diet (20 mg Cd/kg diet). Hematoxylin-eosin (H&E) staining was used to observe the morphological changes, and inductively coupled plasma mass spectrometry (ICP-MS) was performed to detect the levels of ion elements in myocardium. We further detected LXA4 and its receptor FPR2, TGF-β, Nrf2, NF-κB pathway and necroptosis related-genes expressions by RT-PCR and western blot. The results showed that Cd exposure induced necrotic cell death and ion homeostasis imbalance in swine myocardium. Moreover, Cd exposure increased the LXA4 content, inhibited the FPR2 expression, activated TGF-β pathway and suppressed Nrf2 pathway, activating the NF-κB pathway. In addition, Cd exposure increased the expressions of necroptosis related-genes TNF-α, TNFR1, RIP1, RIP3 and MLKL. It indicated Cd exposure induced necroptosis via FPR2/TGF-β/NF-κB pathway, revealing the potential mechanism of Cd-induced cardiotoxicity in swine myocardium.

CaMKII as a key regulator of contrast-induced nephropathy through mPTP opening in HK-2 cells

Contrast-induced nephropathy (CIN), refers to acute kidney injury observed after administration of contrast media during angiographic or other medical procedures such as urography, and accounting for 12% of all causes of acute renal failure, but no specific prevention or treatment strategy exists for its obscure pathophysiology. The aim of our study was to explore the influence of calcium/calmodulin-dependent protein kinase II (CaMKII) in CIN by using HK-2 cells. Knockdown of CypD was achieved by lentivirus, and CaMKII overexpression by transfection with the plasmid. In this study, we have demonstrated that CypD-mediated mPTP opening triggered mitochondrial dysfunction and tubule cells apoptosis in CIN. We also found that iohexol treatment was associated with mitochondrial ROS overloading, ATP depletion and LDH release. Inhibition of CypD with the pharmacologic inhibitor or knockdown of CypD abrogated mPTP opening, oxidative stress, mitochondria damage, and cell apoptosis induced by iohexol. In addition, we found that inhibition of the CaMKII activity alleviated iohexol-induced CypD expression, whereas also decreased mPTP opening, oxidative stress, mitochondria damage, and cell apoptosis, similarly to the inhibition of CypD did. Moreover, CaMKII overexpression enhanced iohexol-induced mPTP opening, mitochondrial damage and renal tubular epithelial cells apoptosis. These findings first identified the novel role of CaMKII in iohexol-induced tubular cells apoptosis and delineated the CaMKII-CypD/mPTP pathway during contrast-induced tubular cell damage. Hence, these results could provide a new strategy for CIN protection.