M2-Type Macrophages and Cancer-Associated Fibroblasts Combine to Promote Colorectal Cancer Liver Metastases.

Purpose: This research explored the association between CD163-labeled M2-type macrophages and cancer-associated fibroblasts (CAFs) in the tumor microenvironment (TME) of 38 colorectal cancer (CRC) liver metastases. In addition, we investigated the correlation differences between M2-type macrophages and CAFs in the tumor microenvironments of 38 primary colorectal cancer patients with confirmed liver metastases and 946 colorectal cancer patients, as well as possible mechanisms of action between the two cells. Methods: The Immunohistochemistry (IHC) method was applied to detect the expression levels of M2-type macrophages and CAFs in the tissues of 984 cases of CRC and to analyze the correlation between M2-type macrophages and CAFs in colorectal cancer tissues. The IHC method was also applied to detect the expression levels of M2-type macrophages and CAFs in the liver metastases of 38 cases of CRC in the experimental group and to analyze the correlation between the two cells in liver metastases. Results: 1. M2-type macrophages and CAFs expression were significantly higher in 38 primary colorectal cancer patients compared to 946 controls, and the expression of M2-type macrophages was significantly positively correlated with CAFs. 2. In 984 CRC cases, M2-type macrophages and CAFs expression levels were significantly higher in the cancer tissues than in the paired paracancerous tissues. 3. The expression levels of M2-type macrophages and CAFs in primary colorectal cancer were significantly higher in the experimental group than in colorectal cancer tissues without distant metastasis. Conclusion: M2-type macrophages and CAFs are involved in the development of the colorectal cancer tumor microenvironment, and their interaction influences the initiation and progression of liver metastasis in colorectal cancer. It may provide new clinical ideas for early diagnosis of CRC liver metastases and searching for immune targets.

Ferroptosis Exists in Ischemia Reperfusion Injury after Cardiac Surgery with Cardiopulmonary Bypass.

Ischemia-reperfusion (IR) injury commonly arises during cardiac surgery involving Cardiopulmonary Bypass (CPB), and it has relationship with ferroptosis in mice. However, the exact role of ferroptosis in the human cardiac damage caused by cardiac surgery remains unclear. Basic patient data and perioperative period information were collected, and clinic indicators related to cardiac function were detected to assess the extent of cardiac injury. Cardiac tissue samples were collected to determine histopathological changes, ultrastructure of mitochondrial and hallmarks of ferroptosis. 25 patients were involved in this study. In the present study, we observed a significant increase in the clinical indicator hs-cTnT, with levels rising more than 1393 ± 242 folds (P < 0.0001) following the cardiac surgery. Masson staining revealed a notable increase in fibrosis levels by 2.282 ± 0.259% (P = 0.0009). Furthermore, there was a significant elevation in lipid peroxidation, as evidenced by a 61.42 ± 17.33% increase in MDA (P = 0.0006). Additionally, we observed notable swelling, decreased mitochondrial crista, and even fragmented mitochondria. Notably, changes in the marker gene of ferroptosis were observed, with PTGS2 showing a 6.437 ± 0.81 folds increase (P < 0.0001). Furthermore, key regulators such as SLC7A11 and GPX4 proteins exhibited a reduction of 97.33 ± 25.78% (P = 0.0068) and 60.59 ± 14.93% (P = 0.0071), respectively, indicating the occurrence of ferroptosis following the surgery. Ferroptosis exists in myocardial IR injury caused by cardiac surgery with CPB, indicating that targeting ferroptosis could serve as a potential strategy for myocardial protection against CPB-induced IR injury. The trial has been registered in Chinese Clinical Trial Registry (ChiCTR, No. ChiCTR2200061995) on July 16th, 2022.

Health outcomes associated with phytosterols: An umbrella review of systematic reviews and meta-analyses of randomized controlled trials.

BACKGROUND: Phytosterols (PS), as a kind of plant active ingredients, have many benefits to human health. However, there is currently no comprehensive overview of the clinical evidence and an assessment of the evidence quality. PURPOSE: We conducted an umbrella review, which incorporated verification spanning a number of meta-analyses and systematic reviews to clarify the link that existed between PS consuming and health outcomes. METHODS: The databases PubMed, Embase, Web of Science and The Cochrane Library were searched for appropriate research and ultimately included 23 articles involving 79 results. Methodological quality and the validity of evidence received designation in the included meta-analyses leveraging the Assessment of Multiple Systematic Reviews (AMSTAR-2) and the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). RESULTS: The consumption of PS makes a contribution to the alleviation of metabolic conditions such as hypercholesterolemia, diabetes, obesity, and hypertension. Its most essential function is to decrease cholesterol absorption, leading to dramatically reductions in total cholesterol and low density lipoprotein cholesterol. Furthermore, utilizing PS products can have a favorable impact on managing apolipoprotein levels along with decreasing the probability of obtaining atherosclerotic cardiovascular disease. CONCLUSION: This umbrella review summarized a range of beneficial functions of PS to humans, highlighting the promising potential for the development of PS into functional foods.

Fisetin, a dietary flavonoid, promotes transintestinal cholesterol excretion through the activation of PPARδ.

Fisetin, a dietary polyphenol abundantly found in strawberries, exhibits a broad spectrum of health-promoting activities, including antihyperlipidemic effects. This study aimed to investigate the regulatory effect of fisetin on cholesterol elimination through novel transintestinal cholesterol excretion (TICE) pathway. A hypercholesterolemic mouse model and human colon epithelial cancer cell line Caco-2 were utilized to conduct the study. In hypercholesterolemic mice, fisetin (25 mg/kg) treatment reduced serum total cholesterol by 46.48% and significantly decreased lipid accumulation in the liver. Furthermore, fisetin administration led to a substantial increase in the fecal neutral sterol contents, including coprostanol, coprostanone, dihydrocholesterol, and cholesterol. Specifically, these sterol contents increased by approximately 224.20%, 151.40%, 70.40% and 50.72% respectively. The fluorescence intensity of 22-NBD-cholesterol in intestinal perfusion increased by 95.94% in fisetin group (25 mg/kg), indicating that fisetin stimulated TICE. In high cholesterol-induced Caco-2 cells, fisetin at a concentration of 30 µM reduced total cholesterol and free cholesterol by 37.21% and 45.30% respectively, stimulated cholesterol excretion, and inhibited cholesterol accumulation. Additionally, fisetin upregulated the gene and protein expression of cholesterol efflux transporters ABCG5/G8 and ABCB1, while downregulating the cholesterol uptake regulator NPC1L1. Furthermore, fisetin increased LDLR protein expression and decreased PCSK9 expression. Notably, fisetin significantly activated nuclear receptor PPARδ in Caco-2 cells. PPARδ antagonist pretreatment counteracted the regulatory effects of fisetin on TICE regulators, suggesting fisetin lowered cholesterol through enhancing TICE by activation of intestinal PPARδ. Fisetin could be used as functional dietarysupplement for eliminating cholesterol and reducing the incidence of cardiovascular diseases.

Hawthorn fruit extract protect against MC-LR-induced hepatotoxicity by attenuating oxidative stress and apoptosis.

Microcystins (MCs) is a class of cyclic heptapeptide compounds with biological activity. There is no effective treatment for liver injury caused by MCs. Hawthorn is a medicinal and edible plant traditional Chinese medicine with hypolipidemic, reducing inflammation and oxidative stress in the liver. This study discussed the protective effect of hawthorn fruit extract (HFE) on liver damage caused by MC-LR and the underlying molecular mechanism. After MC-LR exposure, pathological changes were observed and hepatic activity of ALT, AST and ALP were increased obviously, but they were remarkably restored with HFE administration. In addition, MC-LR could significantly reduce SOD activity and increase MDA content. Importantly, MC-LR treatment resulted in mitochondrial membrane potential decreased, and Cytochrome C release, eventually leading to cell apoptosis rate increase. HFE pretreatment could significantly alleviate the above abnormal phenomena. To examine the mechanism of protection, the expression of critical molecules in the mitochondrial apoptosis pathway was examined. The levels of Bcl-2 was inhibited, and the levels of Bax, Caspase-9, Cleaved Caspase-9, and Cleaved caspase-3 were upregulated after MC-LR treatment. HFE reduced MC-LR-induced apoptosis via reversing the expression of key proteins and genes in the mitochondrial apoptotic pathway. Hence, HFE could alleviate MC-LR induced hepatotoxicity by reducing oxidative stress and apoptosis.

Galangin inhibited ferroptosis through activation of the PI3K/AKT pathway in vitro and in vivo.

Ferroptosis is an iron-dependent form of nonapoptotic cell death characterized by the accumulation of lipid peroxides in cells. In recent years, extensive attention has been dedicated to exploring safe and effective natural ferroptosis regulators which can provide novel treatment strategies for ferroptosis-related diseases. This study identified galangin, a natural flavonoid, as an effective inhibitor of ferroptosis, which could increase cell viability in RSL3-inhibited HT1080 cells, decrease levels of lipid ROS and MDA, improve PTGS2 mRNA expression, and enhance the expression of glutathione peroxidase 4 (GPX4). Ferroptosis is widely present in ischemia-reperfusion (IR) injury. This study found that galangin significantly ameliorated the pathological damage of liver tissue in mice with IR, reduced levels of serum ALT, AST, and MDA, and increased the expression of GPX4. The results of RNA-seq exhibited ferroptosis was significant and the PI3K/AKT pathway deserved to explore the inhibition effects of galangin on ferroptosis. Indeed, galangin treatment significantly rescued RSL3-inhibited phosphorylation levels of PI3K, AKT, and CREB proteins, and the ferroptosis inhibitory effects of galangin were counteracted by PI3K inhibitor LY294002. These findings indicated that galangin may exert its anti-ferroptosis effects via activating the PI3K/AKT/CREB signaling pathway and it will hopefully serve as a promising effective measure to attenuate IR injury by inhibiting ferroptosis.

Effects of sea buckthorn (Hippophae rhamnoides L.) on factors related to metabolic syndrome: A systematic review and meta-analysis of randomized controlled trial.

The purpose of this meta-analysis is to explore whether the supplement of sea buckthorn affects the factors related to metabolic syndrome. The related RCTs from five databases were systematically searched and comprehensively random effects model was used to calculate SMD and 95% CI. The Cochrane deviation risk tool was used to evaluate the deviation risk. Fifteen studies were involved in the meta-analysis. First, sea buckthorn supplementation reduced triglycerides [-0.722 (-1.129, -0.316); p < .001], total cholesterol [-0.345 (-0.639, -0.051); p = .021], low density lipoprotein cholesterol [-0.396 (-0.755, -0.037); p = .031], and increased high density lipoprotein cholesterol [0.370 (0.056, 0.684); p = .021] in overall subjects. Second, subgroup analysis showed that sea buckthorn supplementation reduced lipids only in people with abnormal lipid metabolism. Third, sea buckthorn had no effect on blood sugar, blood pressure, and BMI of the overall subjects. Sea buckthorn may affect the lipid metabolism in circulation, but it cannot affect blood glucose, blood pressure, and BMI. These indicators are closely associated with metabolic syndrome. This study may contribute to the development and utilization of sea buckthorn, and may provide a new and safer way for the prevention and treatment of metabolic syndrome. The limitation of this study is high heterogeneity, even if subgroup analysis is used. However, more clinical studies are needed to determine the real effect of sea buckthorn on metabolic syndrome.

Chronic vitamin D3 supplementation alleviates cognition impairment via inhibition of oxidative stress regulated by PI3K/AKT/Nrf2 in APP/PS1 transgenic mice.

Oxidative stress plays essential role in the pathogenesis of Alzheimer's disease, and vitamin D3 (VD3) is a nutrient with neuroprotective and antioxidant activities. The present study aimed to confirm the neuroprotective effect and the ameliorative effect of cortical oxidative stress of VD3 in APP/PS1 transgenic mice. APP/PS1 mice were treated with VD3 for 20 weeks. After treatment, Morris Water Maze test was used to evaluate cognitive level. Western blotting was used to determine APP, p-tau, tau and PI3K/AKT/Nrf2 pathway-related protein expression levels. Immunohistochemical staining was performed to determine the levels of ß amyloid peptide (Aß) deposition. Enzyme linked immunosorbent assay was used to determine the 25(OH)D3 levels and oxidative stress status. Our results showed that treatment with VD3 ameliorated behavioral deficits of APP/PS1 mice. In addition, the administration of VD3 significantly increased the cortical 25(OH)D3 levels, while reducing the levels of cortical Aß deposition and decreasing the expression levels of cortical APP, tau and p-tau in APP/PS1 mice. Moreover, VD3 protected the cortex against oxidative stress by enhancing the levels of superoxide dismutase, glutathione and total antioxidant capacity, and downregulating the malondialdehyde levels. Furthermore, VD3 clearly activated the PI3K/AKT/Nrf2 pathway, thereby elevating the expression levels of HO1 and NQO1. We concluded that VD3 improved cognitive function and cortical Alzheimer-like pathology of APP/PS1 mice, which may be related to the inhibition of oxidative stress via activation the PI3K/AKT/Nrf2 pathway.

The Regulatory Effects and the Signaling Pathways of Natural Bioactive Compounds on Ferroptosis.

Natural bioactive compounds abundantly presented in foods and medicinal plants have recently received a remarkable attention because of their various biological activities and minimal toxicity. In recent years, many natural compounds appear to offer significant effects in the regulation of ferroptosis. Ferroptosis is the forefront of international scientific research which has been exponential growth since the term was coined. This type of regulated cell death is driven by iron-dependent phospholipid peroxidation. Recent studies have shown that numerous organ injuries and pathophysiological processes of many diseases are driven by ferroptosis, such as cancer, arteriosclerosis, neurodegenerative disease, diabetes, ischemia-reperfusion injury and acute renal failure. It is reported that the initiation and inhibition of ferroptosis plays a pivotal role in lipid peroxidation, organ damage, neurodegeneration and cancer growth and progression. Recently, many natural phytochemicals extracted from edible plants have been demonstrated to be novel ferroptosis regulators and have the potential to treat ferroptosis-related diseases. This review provides an updated overview on the role of natural bioactive compounds and the potential signaling pathways in the regulation of ferroptosis.

Role of Long Noncoding RNAs ZlMSTRG.11348 and UeMSTRG.02678 in Temperature-Dependent Culm Swelling in Zizania latifolia.

Temperature influences the physiological processes and ecology of both hosts and endophytes; however, it remains unclear how long noncoding RNAs (lncRNAs) modulate the consequences of temperature-dependent changes in host-pathogen interactions. To explore the role of lncRNAs in culm gall formation induced by the smut fungus Ustilago esculenta in Zizania latifolia, we employed RNA sequencing to identify lncRNAs and their potential cis-targets in Z. latifolia and U. esculenta under different temperatures. In Z. latifolia and U. esculenta, we identified 3194 and 173 lncRNAs as well as 126 and four potential target genes for differentially expressed lncRNAs, respectively. Further function and expression analysis revealed that lncRNA ZlMSTRG.11348 regulates amino acid metabolism in Z. latifolia and lncRNA UeMSTRG.02678 regulates amino acid transport in U. esculenta. The plant defence response was also found to be regulated by lncRNAs and suppressed in Z. latifolia infected with U. esculenta grown at 25 °C, which may result from the expression of effector genes in U. esculenta. Moreover, in Z. latifolia infected with U. esculenta, the expression of genes related to phytohormones was altered under different temperatures. Our results demonstrate that lncRNAs are important components of the regulatory networks in plant-microbe-environment interactions, and may play a part in regulating culm swelling in Z. latifolia plants.

Impaired pain empathic abilities among patients with functional dyspepsia.

INTRODUCTION: Brain structure or functioning abnormality in regions such as insula and anterior cingulate cortex (ACC) is associated with functional dyspepsia (FD) and pain empathy, but the relationship between FD and pain empathy remains unclear. The aim of this study was to compare the pain empathic abilities of FD patients and healthy controls (HCs) and investigate the association of pain empathy with clinical characteristics and quality of life of FD patients. METHODS: Pain empathic abilities was measured in 30 FD patients and 30 HCs using a validated pain empathy paradigm. Demographic characteristics, Helicobacter pylori status, duration, dyspeptic symptom score and Nepean Dyspepsia Life Quality Index (NDLQI) were obtained from all patients. RESULTS: FD patients scored higher than HCs when rating painful pictures, but the accuracy for painful pictures was significantly lower than HCs. Pearson correlation analysis showed significant negative correlation between NDLQI and pain rating scores for painful pictures. When sex, age, educational level, the number of complaints, duration, H. pylori infection and NDLQI were included in multiple linear regression analysis, NDLQI was independently associated with pain ratings. CONCLUSIONS: FD patients showed abnormally enhanced pain empathic abilities, which may be associated with the severity of symptoms and quality of life.

Abdominal obesity and risk of CVD: a dose-response meta-analysis of thirty-one prospective studies.

This meta-analysis aimed to study the relationship between abdominal obesity and the risk of CVD by waist circumference (WC), waist:hip ratio (WHR) and waist:height ratio (WHtR). We systematically searched PubMed, Embase and Web of Science. Prospective studies that estimated cardiovascular events by WC, WHR and WHtR were included in this study. Pooled relative risks with 95 % CI were calculated using random effects models. A total of thirty-one studies were included in the meta-analysis, including 669 560 participants and 25 214 cases. Compared the highest with the lowest category of WC, WHR and WHtR, the summary risk ratios were 1·43 (95 % CI, 1·30, 1·56, P < 0·001), 1·43 (95 % CI, 1·33, 1·54, P < 0·001) and 1·57 (95 % CI, 1·37, 1·79, P < 0·001), respectively. The linear dose-response analysis revealed that the risk of CVD increased by 3·4 % for each 10 cm increase of WC, and by 3·5 and 6·0 % for each 0·1 unit increase of WHR and WHtR in women, respectively. In men, the risk of CVD increased by 4·0 % for each 10 cm increase of WC, and by 4·0 and 8·6 % for each 0·1 unit increase of WHR and WHtR, respectively. Collectively, abdominal obesity is associated with an increased risk of CVD. WC, WHR and WHtR are good indicators for the prediction of CVD.

Impaired decision-making under risk in patients with functional dyspepsia.

INTRODUCTION: The cognitive processing in patients with functional dyspepsia (FD) has not been well established. Decision-making is an important component of cognitive function. Most brain regions involved in decision-making are abnormal in FD patients. This study aimed to investigate the decision-making under ambiguity and risk in FD patients. METHODS: We recruited 40 FD patients meeting Rome III criteria and 40 healthy controls (HCs) matched for age, sex, marital status, and education level. The Hamilton Anxiety Scale (HAMA) and the 17-item Hamilton Depression Scale (HAMD-17) were used to evaluate their anxiety and depression emotions. The Iowa Gambling Task (IGT) and Game of Dice Task (GDT) were used to evaluate decision-making under ambiguity and risk, respectively. Helicobacter pylori status, disease duration, dyspeptic symptom score, and the Nepean Dyspepsia Life Quality Index (NDLQI) were obtained from all patients. RESULTS: In IGT, FD patients had a lower total net score, chose more adverse choices, and showed a slower response to change their behavior than HCs. However, there was no significant difference in the net score of the first 2 blocks between the two groups. In GDT, FD patients had a lower total net score, higher risk score, and lower use of negative feedback than HCs. In addition, FD patients showed better GDT performance than those without early satiation. CONCLUSIONS: FD patients showed impaired decision-making under risk. The deficiency might be related to dyspeptic symptoms of FD patients.

Fisetin Prevents HT22 Cells From High Glucose-Induced Neurotoxicity via PI3K/Akt/CREB Signaling Pathway.

Hyperglycemia has been widely considered as a key risk factor for diabetic encephalopathy which can cause neuronal apoptosis and cognitive deficits. The flavonoid compound, fisetin, possesses potential neuroprotective effects and also enhances learning and memory. However, the role of fisetin in hyperglycemia-induced neuronal cytotoxicity has not been fully elucidated. In the present study, HT22 murine hippocampal neuronal cell line was used to establish the injured cell model. Cell proliferation and cytotoxicity assay, Hoechst 33258 staining, qRT-PCR, western blot analysis, and specific inhibitor were used to investigate the effect and molecular mechanisms of fisetin on high glucose (HG)-induced neurotoxicity in HT22 cells. Our results showed that 125 µM and 48 h of treatment was identified as optimal damage parameter of HG. Fisetin significantly improved HG-inhibited cell viability. The levels of LDH, malondialdehyde (MDA), and superoxide dismutase (SOD) were noticeably modulated by fisetin, which alleviated HG-induced HT22 cell oxidative damage. Besides, the apoptosis of HT22 cells was rescued by fisetin pretreatment. In addition, fisetin also prevented HG-induced downregulation of the mRNA expression of Bdnf, Gdnf, synaptophysin (Syp), and glutamate ionotropic receptor AMPA type subunit 1 (Gria1) in cells. More importantly, the decreased phosphorylation of phosphoinositide 3 kinase (PI3K), Akt, and cAMP-response element binding protein (CREB) was rescued by fisetin treatment and that neuroprotective effect of fisetin was partially blocked by PI3K inhibitor, LY294002. These findings indicate that fisetin has potent neuroprotective effect and prevents HG-induced neurotoxicity by activation of PI3K/Akt/CREB pathway.

The neuroprotective effect and action mechanism of polyphenols in diabetes mellitus-related cognitive dysfunction.

BACKGROUND: Diabetes mellitus (DM) is a complex and prevalent metabolic disorder worldwide. Strong evidence has emerged that DM is a risk factor for the accelerated rate of cognitive decline and the development of dementia. Though traditional pharmaceutical agents are efficient for the management of DM and DM-related cognitive decrement, long-term use of these drugs are along with undesired side effects. Therefore, tremendous studies have focused on the therapeutic benefits of natural compounds at present. Ample evidence exists to prove that polyphenols are capable to modulate diabetic neuropathy with minimal toxicity and adverse effects. PURPOSE: To describe the benefits and mechanisms of polyphenols on DM-induced cognitive dysfunction. In this review, we introduce an updated overview of associations between DM and cognitive dysfunction. The risk factors as well as pathological and molecular mechanisms of DM-induced cognitive dysfunction are summarized. More importantly, many active polyphenols that possess preventive and therapeutic effects on DM-induced cognitive dysfunction and the potential signaling pathways involved in the action are highlighted. CONCLUSIONS: The therapeutic effects of polyphenols on DM-related cognitive dysfunction pave a novel way for the management of diabetic encephalopathy.

Increased total iron and zinc intake and lower heme iron intake reduce the risk of esophageal cancer: A dose-response meta-analysis.

Several epidemiological studies investigated the relationship between dietary intake of essential trace elements and the risk of esophageal cancer (EC), yielding inconsistent results. We therefore conducted a systematic meta-analysis to investigate and quantify the putative association between the intake of various essential trace elements and the risk of EC. We searched Embase, PubMed, and Web of Science for eligible articles published through April 2018 reporting the odds ratio (OR) with 95% confidence interval (95% CI). Pooled results were then calculated using fixed and random effect models. A total of 20 articles containing 4855 cases from 1 387 482 participants were included in our analysis. We found a significant inverse correlation between total iron intake and the risk of EC (OR = 0.81, 95% CI: 0.70-0.94), particularly in Asian populations. A dose-response analysis revealed that each 5 mg/day increase in total iron intake was associated with a 15% reduction in EC risk (OR = 0.85, 95% CI: 0.79-0.92). In contrast, each 1 mg/day increase in heme iron intake was associated with a 21% increase in EC risk (OR = 1.21, 95% CI: 1.02-1.45). Lastly, a pooled risk estimate revealed that each 5 mg/day increase in zinc intake was associated with a 15% reduction in EC risk (OR = 0.85, 95% CI: 0.77-0.93). Taken together, our analysis indicates that increased dietary intake of total iron and zinc, as well as decreased heme iron intake, may be associated with a lower risk of developing esophageal cancer. These findings have important public health implications with respect to preventing this relatively common form of cancer.

Gastrointestinal toxicity induced by microcystins.

Microcystins (MCs) are produced by certain bloom-forming cyanobacteria that can induce toxicity in various organs, including renal toxicity, reproductive toxicity, cardiotoxicity, and immunosuppressive effects. It has been a significant global environmental issue due to its harm to the aquatic environment and human health. Numerous investigators have demonstrated that MC exposure can induce a widespread epidemic of enterogastritis with symptoms similar to food poisoning in areas close to lakes. Both in vivo and in vitro studies have provided evidence of positive associations between MC exposure and gastrointestinal toxicity. The toxicity of MCs on the gastrointestinal tract is multidimensional. MCs can affect gastrointestinal barrier function and shift the structure of gut microbiota in different gut regions. Furthermore, MCs can inhibit the secretion of gastrointestinal digestive enzymes and the release of inflammatory cytokines, which affects the expression of immune-related genes in the intestine. The damage of the intestine is closely correlated to MC exposure because the intestine is the main site for the digestion and absorption of nutrients. The damage to the gastrointestinal tract due to MCs was summarized from different aspects, which can be used as a foundation for further exploration of molecular damage mechanisms.

MC-LR induces dysregulation of iron homeostasis by inhibiting hepcidin expression: A preliminary study.

The liver is an important iron storage site and a primary MC-LR target. C57BL/6 and Hfe-/- mice were used to investigate effects and mechanisms of MC-LR on systematic iron homeostasis. Body weight, tissue iron content, hematological and serological indexes, and histopathological were evaluated. Ultrastructure and iron metabolism-related genes and proteins were analyzed. MC-LR induced dose-dependent increases in red blood cells, hemoglobin, and hematocrit. In contrast MC-LR-induced dose-dependent decreases in mean corpuscular volume, hemoglobin, and hemoglobin concentration were observed both C57BL/6 and Hfe-/- mice. In both mouse species, serological indexes increased. Aggravated liver and spleen iron were observed in C57BL/6 mice, consistent with Perls' Prussian blue staining. However, an opposite trend was observed in Hfe-/- mice. C57BL/6 mice had lower Hamp1 (Hepcidn), Bmp6, Il-6, and Tmprss6. Significant increased Hjv, Hif-1α and Hif-2α were observed in both C57BL/6 and Hfe-/- mice. MC-LR-induced pathological lesions were dose-dependent increase in C57BL/6 mice. More severe pathological injuries in MC-LR groups (25 µg/kg) were observed in Hfe-/- mice than in C57BL/6 mice. In Hfe-/- mice, upon exposure to 25 µg/kg MC-LR, mitochondrial membranes were damaged and mitochondrial counts increased with significant swelling. These results indicated that MC-LR can induce the accumulation of iron in C57BL/6 mice with the occurrence of anemia, similar to thalassemia. Moreover, dysregulation of iron homeostasis may be due to MC-LR-induced Hamp1 downregulation, possibly mediated by hypoxia or the IL6-STAT3 and BMP-SMAD signaling pathways.

Oxidative Stress Mediates Microcystin-LR-Induced Endoplasmic Reticulum Stress and Autophagy in KK-1 Cells and C57BL/6 Mice Ovaries.

Microcystin-leucine arginine (MC-LR) is a cyclic heptapeptide intracellular toxin released by cyanobacteria that exhibits strong reproductive toxicity. However, little is known about its biotoxicity to the female reproductive system. The present study investigates unexplored molecular pathways by which oxidative stress acts on MC-LR-induced endoplasmic reticulum stress (ERs) and autophagy. In the present study, immortalized murine ovarian granular cells (KK-1 cells) were exposed to 8.5, 17, and 34 µg/mL (IC50) of MC-LR with or without N-acetyl-l-cysteine (NAC, 10 mM) for 24 h, and C57BL/6 mice were treated with 12.5, 25.0, and 40.0 µg/kg⋅bw of MC-LR with or without NAC (200 mg/kg⋅bw) for 14 days. The results revealed that MC-LR could induce cells apoptosis and morphologic changes in ovarian tissues, induce oxidative stress by stimulating the generation of reactive oxygen species (ROS), destroying antioxidant capacity, and subsequently trigger ERs and autophagy by inducing the hyper-expression of ATG12, ATG5, ATG16, EIF2α (phosphorylated at S51), CHOP, XBP1, GRP78, Beclin1, and PERK (Thr980). Furthermore, NAC pretreatment partly inhibited MC-LR-induced ERs and autophagy via the PERK/ATG12 and XBP1/Beclin1 pathways. These results suggest that oxidative stress mediated MC-LR-induced ERs and autophagy in KK-1 cells and C57BL/6 mice ovaries. Therefore, oxidative stress plays an important role in female toxicity induced by MC-LR.

Resveratrol Ameliorates Microcystin-LR-Induced Testis Germ Cell Apoptosis in Rats via SIRT1 Signaling Pathway Activation.

Microcystin-leucine arginine (MC-LR), a cyclic heptapeptide produced by cyanobacteria, is a strong reproductive toxin. Studies performed in rat Sertoli cells and Chinese hamster ovary cells have demonstrated typical apoptosis after MC-LR exposure. However, little is known on how to protect against the reproductive toxicity induced by MC-LR. The present study aimed to explore the possible molecular mechanism underlying the anti-apoptosis and protective effects of resveratrol (RES) on the co-culture of Sertoli⁻germ cells and rat testes. The results demonstrated that MC-LR treatment inhibited the proliferation of Sertoli⁻germ cells and induced apoptosis. Furthermore, sirtuin 1 (SIRT1) and Bcl-2 were inhibited, while p53 and Ku70 acetylation, Bax expression, and cleaved caspase-3 were upregulated by MC-LR. However, RES pretreatment ameliorated MC-LR-induced apoptosis and SIRT1 inhibition, and downregulated the MC-LR-induced increase in p53 and Ku70 acetylation, Bax expression, and caspase-3 activation. In addition, RES reversed the MC-LR-mediated reduction in Ku70 binding to Bax. The present study indicated that the administration of RES could ameliorate MC-LR-induced Sertoli⁻germ cell apoptosis and protect against reproductive toxicity in rats by stimulating the SIRT1/p53 pathway, suppressing p53 and Ku70 acetylation and enhancing the binding of Ku70 to Bax.