Potentiation of LPS-Induced Apoptotic Cell Death in Human Hepatoma HepG2 Cells by Aspirin via ROS and Mitochondrial Dysfunction: Protection by N-Acetyl Cysteine

The Protecting Role of Black Seed Oil and Its Nano-Formulation in LPS-Induced Acute Kidney Injury in Mice: Evaluation of Oxidative Stress, Biochemical & Molecular Parameters

Background

Acute kidney injury (AKI) is a medical concern that is accompanied by the rapid deterioration of kidney function. It can be triggered by lipopolysaccharide (LPS) of gram-negative bacteria as it activates a complicated immune response, resulting in widespread inflammation and potential organ dysfunction. Black seed oil (BSO) is rich in beneficial constituents and has been widely used owing to its nutritional advantages.

Purpose

This research is aimed to investigate the potential protective effects of BSO and its nano-formulation on AKI induced by LPS. It also aimed to compare their anti-inflammatory activity with indomethacin, a known synthetic anti-inflammatory drug.

Materials and Methods

Forty-eight mice were placed randomly into 8 groups. A single intraperitoneal (i.p.) injection of 2.5 mg/kg B.W. of LPS was used to trigger inflammation, and pretreatment with BSO and its nano-formulation was at 0.2 mL/kg/day for 14 consecutive days. Indomethacin was used as a reference drug and its efficacy was tested alone or in combination with BSO at lower doses. Renal function was assessed using urea, creatinine, neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1). Also, oxidative and inflammatory markers were assessed by measuring levels of reduced glutathione (GSH), nitric oxide (NO), cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), and toll-like receptor-4 (TLR-4). Histopathological examination of the kidney tissues was also performed.

Results

The study showed that BSO and its nano-formulation had anti-inflammatory effects comparable to or better than those of indomethacin. They greatly decreased the oxidative stress and inflammatory markers induced by LPS. Their protective effect against pathological alterations in kidney tissues was significantly noticed.

Conclusion

BSO and its nano-formulation could be used as nephroprotective and anti-inflammatory supplements.

LPS-Induced Mitochondrial Dysfunction Reduces Oocyte Maturation and Developmental Competence of Buffalo Embryos via ROS Mediated TLR4 Signalling

PROBLEM

Lipopolysaccharide (LPS) from gram-negative bacteria has reportedly been associated with infectious diseases like metritis, which has a substantial adverse effect on animal reproductive performance and causes serious financial losses for the dairy sector. The current work aimed to establish the impact of LPS on in vitro oocyte maturation and subsequent in vitro developmental competence of oocytes, as well as to investigate the explanatory molecular mechanism underlying this effect.

METHOD OF STUDY

Buffalo cumulus-oocyte complexes (COCs) were challenged with 0, 5, 10 and 20 µg/mL LPS during IVM followed by IVF and IVC. Cytoplasmic and nuclear maturation, cleavage and blastocyst rate, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP, ΔΨm) and transcript abundance of genes related to inflammation, antioxidation and apoptosis were evaluated.

RESULTS

The maturation and subsequent embryonic development competency were found to be significantly (p ≤ 0.05) reduced with the addition of 10 and 20 µg/mL LPS to IVM media. ROS production accompanied by a decreased ΔΨm was recorded in LPS-treated oocytes in comparison to the control group (p ≤ 0.05). Our results were further supported by the transcriptional expression of proinflammatory (TLR4, CD14 and RPS27A) and apoptotic gene (Caspase 3) which were found to be significantly increased while antioxidant genes (SOD2 and GPX1) were decreased significantly in matured oocytes and blastocyst after LPS exposure.

CONCLUSIONS

The deleterious effects of LPS are mediated through ROS generation, which triggers inflammatory processes via the TLR4 pathway and impairs oocyte maturation and subsequent embryonic development.

Exposure to atrazine stimulates progesterone secretion and induces oxidative stress, inflammation, and apoptosis in the ovary of pseudopregnant rats

Atrazine (ATR) is one of the most commonly used herbicides worldwide. As an endocrine disruptor, it causes ovarian dysfunction, but the mechanism is unclear. We hypothesized that ATR could affect ovarian steroidogenesis, oxidative stress, inflammation, and apoptosis. In the current study, rats aged 28 days were treated with PMSG and HCG to obtain amounts of corpora lutea. Then, rats were injected with ATR (50 mg/kg/day) or saline (0.9%) for 7 days. Sera were collected to detect biochemical indices and progesterone (P4) level, ovaries were collected for antioxidant status, HE, qPCR, and WB analysis. Results showed that ATR exposure affected growth performance as well as serum TP, GLB, and ALB levels, increased serum P4 level and ovarian mRNA and protein levels of StAR, CYP11A1, and HSD3B. ATR treatment increased ovarian mRNA and protein levels of CREB but not PKA expression. ATR treatment increased ovarian mRNA abundances of Nrf-2 and Nqo1, MDA level, and decreased SOD, GST, and T-AOC levels. ATR exposure increased the mRNA abundances of pro-inflammatory cytokines including Tnf-α, Il-1β, Il-6, Il-18, and Inos. ATR exposure increased the mRNA and protein level of Caspase 3 and the ratio of BAX/BCL-2. In conclusion, NRF-2/NQO1 signaling pathway and CREB might be involved in the regulation of ATR in luteal steroidogenesis, oxidative stress, inflammation, and apoptosis in rat ovary.

Akt Signaling and Nitric Oxide Synthase as Possible Mediators of the Protective Effect of N-acetyl-L-cysteine in Prediabetes Induced by Sucrose

The aim of this work was to evaluate possible mechanisms involved in the protective effect of N-acetyl-L-cysteine (NAC) on hepatic endocrine-metabolic, oxidative stress, and inflammatory changes in prediabetic rats. For that, normal male Wistar rats (60 days old) were fed for 21 days with 10% sucrose in their drinking water and 5 days of NAC administration (50 mg/kg, i.p.) and thereafter, we determined: serum glucose, insulin, transaminases, uric acid, and triglyceride levels; hepatic fructokinase and glucokinase activities, glycogen content, lipogenic gene expression; enzymatic and non-enzymatic oxidative stress, insulin signaling pathway, and inflammatory markers. Results showed that alterations evinced in sucrose-fed rats (hypertriglyceridemia, hyperinsulinemia, and high liver fructokinase activity together with increased liver lipogenic gene expression and oxidative stress and inflammatory markers) were prevented by NAC administration. P-endothelial nitric oxide synthase (P-eNOS)/eNOS and pAKT/AKT ratios, decreased by sucrose ingestion, were restored after NAC treatment. In conclusion, the results suggest that NAC administration improves glucose homeostasis, oxidative stress, and inflammation in prediabetic rats probably mediated by modulation of the AKT/NOS pathway. Administration of NAC may be an effective complementary strategy to alleviate or prevent oxidative stress and inflammatory responses observed in type 2 diabetes at early stages of its development (prediabetes).

Discovery of a synthetic taiwaniaquinoid with potent in vitro and in vivo antitumor activity against breast cancer cells

Taiwaniaquinoids are a unique family of diterpenoids predominantly isolated from Taiwania cryptomerioides Hayata. Previously, we evaluated the antiproliferative effect of several synthetic taiwaniaquinoids against human lung (A-549), colon (T-84), and breast (MCF-7) tumor cell lines. Herein, we report the in vitro and in vivo antitumor activity of the most potent compounds. Their cytotoxic activity against healthy peripheral blood mononuclear cells (PBMCs) has also been examined. We underscore the limited toxicity of compound C36 in PBMCs and demonstrate that it exerts its antitumor effect in MCF-7 cells (IC50 = 1.8 µM) by triggering an increase in reactive oxygen species, increasing the cell population in the sub-G1 phase of the cell cycle (90 %), and ultimately activating apoptotic (49.6 %) rather than autophagic processes. Western blot results suggested that the underlying mechanism of the C36 apoptotic effects was linked to caspase 9 activation and a rise in the Bax/Bcl-2 ratio. In vivo analyses showed normal behavior and hematological parameters in C57BL/6 mice post C36 treatment. Moreover, no significant impact was observed on the biochemical parameters of these animals, indicating that C36 did not induce liver toxicity. Furthermore, C36 demonstrated a significant reduction in tumor growth in immune-competent C57BL/6 mice implanted with E0771 mouse mammary tumor cells, effectively improving survival rates. These findings position taiwaniaquinoids, particularly compound C36, as promising therapeutic candidates for human breast cancer.

Chitooligosaccharide from Pacific White Shrimp Shell Chitosan Ameliorates Inflammation and Oxidative Stress via NF-κB, Erk1/2, Akt and Nrf2/HO-1 Pathways in LPS-Induced RAW264.7 Macrophage Cells

Chitooligosaccharide (COS), found in both insects and marine sources, has several bioactivities, such as anti-inflammation and antioxidant activities. However, the mechanism of shrimp shell COS on retardation of inflammatory and antioxidant effects is limited. Therefore, the aim of this study is to examine the mechanism of the aforementioned activities of COS in LPS-activated RAW264.7 macrophage cells. COS significantly improved cell viability in LPS-activated cells. COS at the level of 500 µg/mL could reduce the TNF-α, NO and IL-6 generations in LPS-activated cells (p < 0.05). Furthermore, COS could reduce ROS formation, NF-κB overactivation, phosphorylation of Erk1/2 and Akt and Nrf2/HO-1 in LPS-exposed cells. These results indicate that COS manifests anti-inflammatory activity and antioxidant action via NF-κB, Erk1/2, Akt and Nrf2/HO-1 signaling with an increasing relevance for inflammatory disorders.

Effective Endotoxin Removal from Chitosan That Preserves Chemical Structure and Improves Compatibility with Immune Cells

Chitosan is one of the most researched biopolymers for healthcare applications, however, being a naturally derived polymer, it is susceptible to endotoxin contamination, which elicits pro-inflammatory responses, skewing chitosan's performance and leading to inaccurate conclusions. It is therefore critical that endotoxins are quantified and removed for in vivo use. Here, heat and mild NaOH treatment are investigated as facile endotoxin removal methods from chitosan. Both treatments effectively removed endotoxin to below the FDA limit for medical devices (<0.5 EU/mL). However, in co-culture with peripheral blood mononuclear cells (PBMCs), only NaOH-treated chitosan prevented TNF-α production. While endotoxin removal is the principal task, the preservation of chitosan's structure is vital for the synthesis and lysozyme degradation of chitosan-based hydrogels. The chemical properties of NaOH-treated chitosan (by FTIR-ATR) were significantly similar to its native composition, whereas the heat-treated chitosan evidenced macroscopic chemical and physical changes associated with the Maillard reaction, deeming this treatment unsuitable for further applications. Degradation studies conducted with lysozyme demonstrated that the degradation rates of native and NaOH-treated chitosan-genipin hydrogels were similar. In vitro co-culture studies showed that NaOH hydrogels did not negatively affect the cell viability of monocyte-derived dendritic cells (moDCs), nor induce phenotypical maturation or pro-inflammatory cytokine release.

In Vitro Antitumor and Anti-Inflammatory Activities of Allium-Derived Compounds Propyl Propane Thiosulfonate (PTSO) and Propyl Propane Thiosulfinate (PTS)

Increasing rates of cancer incidence and the side-effects of current chemotherapeutic treatments have led to the research on novel anticancer products based on dietary compounds. The use of Allium metabolites and extracts has been proposed to reduce the proliferation of tumor cells by several mechanisms. In this study, we have shown the in vitro anti-proliferative and anti-inflammatory effect of two onion-derived metabolites propyl propane thiosulfinate (PTS) and propyl propane thiosulfonate (PTSO) on several human tumor lines (MCF-7, T-84, A-549, HT-29, Panc-1, Jurkat, PC-3, SW-837, and T1-73). We observed that this effect was related to their ability to induce apoptosis regulated by oxidative stress. In addition, both compounds were also able to reduce the levels of some pro-inflammatory cytokines, such as IL-8, IL-6, and IL-17. Therefore, PTS and PTSO may have a promising role in cancer prevention and/or treatment.

Influences of calorie restriction and lipopolysaccharide therapy on inflammation, cytokine response, and cell proliferation in pancreatic adenocarcinoma mouse model

The study aimed to investigate the effects of lipopolysaccharide (LPS) alone and in combination with calorie restriction (CR) on the pancreatic tissues in C57BL/6 mice modeled with pancreatic ductal adenocarcinoma (PDAC). Forty male C57BL/6 mice (10-13 weeks old) were divided into five groups; LPS, LPS + CR, PDAC, PDAC + LPS, and PDAC + LPS + CR. Nuclear factor kappa B (NF-κβ), interleukin-6 (IL-6), and c-Jun N-terminal kinases (JNK) mRNA expression levels were measured in pancreatic tissues. NF-κβ, IL-6, JNK, and proliferating cell nuclear antigen (PCNA) peptide levels were determined by immunohistochemistry. Oxidative stress markers and antioxidant enzyme activities were determined spectrophotometrically. TH1/TH2 cytokine measurements were determined by a flow cytometer. It was detected that the number of PCNA immune + cells in the PDAC + LPS + CR group was significantly lower than in the PDAC and PDAC + LPS groups (p < 0.01, p < 0.05 respectively). PDAC + LPS + CR group's plasma interferon-gamma (IFN-γ), IL-6, IL-2, tumor necrosis factor-alpha, IL-3, and IL-4 levels were found to be significantly lower than the PDAC group (p < 0.01, p < 0.001, p < 0.01, p < 0.05, p < 0.01, and p < 0.05 respectively). According to our findings, the combination of low-dose LPS and 40% CR was found to be more effective in PDAC model mice.

Sodium Propionate or Sodium Butyrate Promotes Fatty Acid Oxidation in HepG2 Cells Under Oxidative Stress

The beneficial effects of sodium butyrate (NaB) and sodium propionate (NaP) on fatty acid oxidation (FAO) genes and production of proinflammatory cytokines related to nonalcoholic fatty liver disease (NAFLD) were evaluated using HepG2 human liver hepatocellular carcinoma cells exposed to palmitate/oleate or lipopolysaccharides (LPSs) as a model. The results showed that NaP or NaB was able to promote FAO, regulate lipolysis, and reduce reactive oxygen species production by significantly increasing the mRNA expression of peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), peroxisome proliferator-activated receptor alpha (PPARα), adipose triglyceride lipase (ATGL), carnitine palmitoyltransferase 1 alpha (CPT1α), fibroblast growth factor 21 (FGF21), and uncoupling protein 2 (UCP2) in HepG2 cells. Together, NaP and NaB may produce greater effects by increasing CPT1α, PPARα, and UCP2 mRNA expression in LPS-treated HepG2 cells and by increasing CPT1α and ATGL mRNA expression in palmitate-/oleate-treated HepG2 cells. Only NaP treatment significantly increased FGF21 mRNA expression in palmitate-/oleate-treated HepG2 cells. The enzyme-linked immunosorbent assay results revealed that only pretreatment with LPSs and not palmitate/oleate significantly increased tumor necrosis factor alpha (TNF-α) expression in HepG2 cells. NaP alone or in combination with NaB significantly decreased TNF-α expression in LPS-induced HepG2 cells. The expression of interleukin-8 in both models showed no significant differences in all treatments. NaP and NaB show potential for in vivo studies on NAFLD.

Characterization of hepatic inflammatory changes in a C57BL/6J mouse model of alpha1-antitrypsin deficiency

Alpha-1 antitrypsin deficiency (AATD) is a genetic disease caused by a hepatic accumulation of mutant alpha-1 antitrypsin (ZAAT). Individuals with AATD are prone to develop a chronic liver disease that remains undiagnosed until late stage of the disease. Here, we sought to characterize the liver pathophysiology of a human transgenic mouse model for AATD with a manifestation of liver disease compared with normal transgenic mice model. Male and female transgenic mice for normal (Pi*M) and mutant variant (Pi*Z) human alpha-1 antitrypsin at 3 and 6 mo of age were subjected to this study. The progression of hepatic ZAAT accumulation, hepatocyte injury, steatosis, liver inflammation, and fibrotic features were monitored by performing an in vivo study. We have also performed a Next-Gene transcriptomic analysis of the transgenic mice liver tissue 16 h after lipopolysaccharide (LPS) administration to delineate liver inflammatory response in Pi*Z mice as compared with Pi*M. Our results show hepatic ZAAT accumulation, followed by hepatocyte ballooning and liver steatosis developed at 3 mo in Pi*Z mice compared with the mice carrying normal variant of human alpha-1 antitrypsin. We observed higher levels of hepatic immune cell infiltrations in both 3- and 6-mo-old Pi*Z mice compared with Pi*M as an indication of liver inflammation. Liver fibrosis was observed as accumulation of collagen in 6-mo-old Pi*Z liver tissues compared with Pi*M control mice. Furthermore, the transcriptomic analysis revealed a dysregulated liver immune response to LPS in Pi*Z mice compared with Pi*M. Of particular interest for translational work, this study aims to establish a mouse model of AATD with a strong manifestation of liver disease that will be a valuable in vivo tool to study the pathophysiology of AATD-mediated liver disease. Our data suggest that the human transgenic mouse model of AATD could provide a suitable model for the evaluation of therapeutic approaches and preventive reagents against AATD-mediated liver disease.NEW & NOTEWORTHY We have characterized a mouse model of human alpha-1 antitrypsin deficiency with a strong manifestation of liver disease that can be used as an in vivo tool to test preventive and therapeutic reagents. Our data explores the altered immunophenotype of alpha-1 antitrypsin-deficient liver macrophages and suggests a relationship between acute inflammation, immune response, and fibrosis.

Alterations in Inflammatory Cytokines and Redox Homeostasis in LPS-Induced Pancreatic Beta-Cell Toxicity and Mitochondrial Stress: Protection by Azadirachtin

Inflammation and redox imbalance are hallmarks of cancer, diabetes, and other degenerative disorders. Pathophysiological response to these disorders leads to oxidative stress and mitochondrial dysfunction by alterations and reprogramming in cellular signaling and metabolism. Pancreatic beta cells are very sensitive to the inflammatory and altered nutrient signals and hence play a crucial role in diabetes and cancer. In this study, we treated insulin-secreting pancreatic beta cells, Rin-5F, with the bacterial endotoxin, LPS (1 μg/ml) to induce an inflammatory response in vitro and then treated the cells with a known anti-inflammatory, anticancer and antioxidant phytochemical, azadirachtin (AZD, 25 µM for 24 h). Our results demonstrated lipid peroxidation and nitric oxide production causing increased nitro/oxidative stress and alterations in the activities of anti-oxidant enzymes, superoxide dismutase and catalase after LPS treatment. Pro-inflammatory responses caused by translocation of nuclear factor kappa B and release of inflammatory cytokines were also observed. These changes were accompanied by GSH-dependent redox imbalance and alterations in mitochondrial membrane potential and respiratory complexes enzyme activities leading to mitochondrial respiratory dysfunction, reduced ATP synthesis, and intrinsic caspase-9 mediated apoptosis. Caspase-9 was activated due to alterations in Bcl-2 and Bax proteins and release of cytochrome c into the cytosol. The activities of oxidative stress-sensitive mitochondrial matrix enzymes, aconitase, and glutamate dehydrogenase were also inhibited. Treatment with AZD showed beneficial effects on the recovery of antioxidant enzymes, inflammatory responses, and mitochondrial functions. GSH-dependent redox homeostasis also recovered after the treatment with AZD. This study may help in better understanding the etiology and pathogenesis of inflammation-induced disorders in pancreatic beta cells to better manage therapeutic strategies.

Cannabinoids Alleviate the LPS-Induced Cytokine Storm via Attenuating NLRP3 Inflammasome Signaling and TYK2-Mediated STAT3 Signaling Pathways In Vitro

Cannabinoids, mainly cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), are the most studied group of compounds obtained from Cannabis sativa because of their several pharmaceutical properties. Current evidence suggests a crucial role of cannabinoids as potent anti-inflammatory agents for the treatment of chronic inflammatory diseases; however, the mechanisms remain largely unclear. Cytokine storm, a dysregulated severe inflammatory response by our immune system, is involved in the pathogenesis of numerous chronic inflammatory disorders, including coronavirus disease 2019 (COVID-19), which results in the accumulation of pro-inflammatory cytokines. Therefore, we hypothesized that CBD and THC reduce the levels of pro-inflammatory cytokines by inhibiting key inflammatory signaling pathways. The nucleotide-binding and oligomerization domain (NOD)-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome signaling has been implicated in a variety of chronic inflammatory diseases, which results in the release of pyroptotic cytokines, interleukin-1β (IL-1β) and IL-18. Likewise, the activation of the signal transducer and activator of transcription-3 (STAT3) causes increased expression of pro-inflammatory cytokines. We studied the effects of CBD and THC on lipopolysaccharide (LPS)-induced inflammatory response in human THP-1 macrophages and primary human bronchial epithelial cells (HBECs). Our results revealed that CBD and, for the first time, THC significantly inhibited NLRP3 inflammasome activation following LPS + ATP stimulation, leading to a reduction in the levels of IL-1β in THP-1 macrophages and HBECs. CBD attenuated the phosphorylation of nuclear factor-κB (NF-κB), and both cannabinoids inhibited the generation of oxidative stress post-LPS. Our multiplex ELISA data revealed that CBD and THC significantly diminished the levels of IL-6, IL-8, and tumor necrosis factor-α (TNF-α) after LPS treatment in THP-1 macrophages and HBECs. In addition, the phosphorylation of STAT3 was significantly downregulated by CBD and THC in THP-1 macrophages and HBECs, which was in turn attributed to the reduced phosphorylation of tyrosine kinase-2 (TYK2) by CBD and THC after LPS stimulation in these cells. Overall, CBD and THC were found to be effective in alleviating the LPS-induced cytokine storm in human macrophages and primary HBECs, at least via modulation of NLRP3 inflammasome and STAT3 signaling pathways. The encouraging results from this study warrant further investigation of these cannabinoids in vivo.

Azadirachtin Attenuates Lipopolysaccharide-Induced ROS Production, DNA Damage, and Apoptosis by Regulating JNK/Akt and AMPK/mTOR-Dependent Pathways in Rin-5F Pancreatic Beta Cells

Pancreatic inflammation and the resulting cellular responses have been implicated in pancreatitis, diabetes, and pancreatic cancer. Inflammatory responses due to the bacterial endotoxin, lipopolysaccharide (LPS), have been demonstrated to alter cellular metabolism, autophagy, apoptosis, and cell proliferation in different cell populations, and hence increases the risks for organ toxicity including cancer. The exact molecular mechanism is however not clear. In the present study, we investigated the role and mechanism of an antioxidant, azadirachtin (AZD), a limonoid extracted from the neem tree (Azadirachta indica), against LPS-induced oxidative stress in the pancreatic β-cell line, Rin-5F. We demonstrated that cells treated with LPS (1 µg/mL for 24 h) showed increased reactive oxygen species (ROS) production, DNA damage, cell cycle arrest, and apoptosis. Our results also showed that LPS induced alterations in the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathways, suppressing autophagy and augmenting apoptosis. Treatment with Azadirachtin (25 µM for 24 h), on the other hand, rendered some degree of protection to the pancreatic cells from apoptosis by inducing the autophagy signals required for cell survival. These results may have significance in elucidating the mechanisms of pancreatic β-cell survival and death by balancing the molecular communication between autophagy and apoptosis under inflammatory and pathological conditions.

Effect of bacterial LPS, poly I:C and temperature on the immune response of coelomocytes in short term cultures of red sea urchin (Loxechinus albus)

In echinoderms, the immune system plays a relevant role in defense against infection by pathogens. Particularly, in sea urchins, the immune system has been shown to be complex, especially in terms of the variety of immune genes and molecules described. A key component of the response to external pathogens are the Toll-like receptors (TLRs), which are a well-characterized class of pattern recognition receptors (PRRs) that participate in the recognition of pathogen-associated molecular patterns (PAMPs). Despite the fact that TLRs have been described in several sea urchin species, for the red sea urchin (Loxechinus albus), which is one of the most important sea urchins across the world in terms of fisheries, limited information on the TLR-mediated immune response exists. In the present study, for the first time, we evaluated the effect of thermal stress, LPS and poly I:C treatment on the coelomocyte immune response of Loxechinus albus to determine how these factors modulate TLR and strongylocin (antimicrobial peptides of echinoderms) responses. We show that the tlr3-like, tlr4-like, tlr6-like and tlr8-like transcripts are modulated by poly I:C, while LPS only modulates the tlr4-like response; there was no effect of temperature on TLR expression, as evaluated by RT-qPCR. Additionally, we showed that strongylocin-1 and strongylocin-2 are modulated in response to simulated viral infection with poly I:C, providing the first evidence of strongylocin expression in L. albus. Finally, we determined that temperature and LPS modify the viability of coelomocytes, while poly I:C treatment did not affect the viability of these cells. This study contributes to the knowledge of immune responses in sea urchins to improve the understanding of the role of TLRs and strongylocins in echinoderms.

Centrality of G6PD in COVID-19: The Biochemical Rationale and Clinical Implications

Introduction: COVID-19 is a novel and devastating disease. Its manifestations vary from asymptomatic to lethal. Moreover, mortality rates differ based on underlying health conditions and ethnicity. We investigated the biochemical rationale behind these observations using machine reasoning by the sci.AI system (https://sci.ai/). Facts were extracted and linked from publications available in nlm.nih.gov and Europe PMC to form the dataset which was validated by medical experts. Results: Based on the analysis of experimental and clinical data, we synthesized detailed biochemical pathways of COVID-19 pathogenesis which were used to explain epidemiological and clinical observations. Clinical manifestations and biomarkers are highlighted to monitor the course of COVID-19 and navigate treatment. As depicted in the Graphical Abstract, SARS-CoV-2 triggers a pro-oxidant (PO) response leading to the production of reactive oxygen species (ROS) as a normal innate defense. However, SARS-CoV-2's unique interference with the antioxidant (AO) system, through suppression of nitric oxide (NO) production in the renin- angiotensin-aldosterone system (RAAS), leads to an excessive inflammatory PO response. The excessive PO response becomes critical in cohorts with a compromised AO system such as patients with glucose-6-phosphate dehydrogenase deficiency (G6PDd) where NO and glutathione (GSH) mechanisms are impaired. G6PDd develops in patients with metabolic syndrome. It is mediated by aldosterone (Ald) which also increases specifically in COVID-19. Conclusion: G6PD is essential for an adequate immune response. Both G6PDd and SARS-CoV-2 compromise the AO system through the same pathways rendering G6PDd the Achilles' heel for COVID-19. Thus, the evolutionary antimalarial advantage of the G6PDd cohort can be a disadvantage against SARS-CoV-2.

Long-term high-concentrate diet feeding induces apoptosis of rumen epithelial cells and inflammation of rumen epithelium in dairy cows

The aim of the present study was to evaluate how long-term high-concentrate diet feeding affected rumen epithelium (RE) of dairy cows. So, 12 mid-lactating multiparous cows were divided into two groups randomly fed either with high-concentrate diet (HC, concentrate: forage = 6: 4) or low-concentrate diet (LC, concentrate: forage = 4:6) for 20 weeks. Remarkable upregulation of lipopolysaccharide (LPS) level and depress of pH in rumen fluid were induced by HC compared with LC group. mRNA abundance of interleukin-6 (IL-6), interleukin-8 (IL-8), C-C motif chemokine ligand 5 (CCL5), caspase-3, caspase-8, and caspase-9 were elevated in RE of HC group compared with LC group. Greater protein abundance of phosphorylated NF-κB p65, IL-6, and tumor necrosis factor α (TNF-α) was observed in RE of cows fed HC than that fed LC. Abundance of protein related to proapoptotic response (cytochrome c, BAX and caspase-3) in HC group was greater than that in LC group, while the abundance of anti-apoptotic factor protein (Bcl-2) was lower in HC group than LC group. Therefore, the present study demonstrated that long-term high-concentrate diet feeding upregulated LPS level in rumen fluid and induced the proinflammatory response in the rumen epithelium and apoptosis of rumen epithelial cells.

Effects of increasing lipopolysaccharide concentrations on in vitro developmental competence of ovine oocytes

Although a considerable number of studies have investigated the effects of lipopolysaccharide (LPS) on the reproductive performance of dairy cows, the response of ovine oocytes to LPS during their in vitro maturation and development is not well defined yet. Ewe’s ovaries were obtained from a slaughterhouse, the oocytes were collected and matured in the presence of increasing concentrations (0, 0.01, 0.1, 1 and 10 µg/mL) of LPS in order to evaluate the meiotic maturation by measuring the proportion of oocytes reaching the MII stage. The concentration of intracellular glutathione (GSH) was measured in oocytes following maturation in vitro. In addition, concentrations of selected metabolites including glucose, pyruvate, lactate and glutamine were quantified in the medium following maturation. A number of treated matured oocytes along with the control group were subsequently fertilized using frozen semen and assessed for the rate of cleavage and for the proportion reaching the blastocyst stage. The number of oocytes in MII stage was significantly reduced in response to the increasing concentrations of LPS (77.83%, 70.64%, 68.86%, 66.32%, respectively, in case of 0.01, 0.1, 1 and 10 µg/mL LPS when compared to the control group, 76.34%; P<0.05). There were no differences neither in the intracellular concentration of GSH in the oocytes nor in case of the metabolites in the maturation medium. Although the rate of cleaved oocytes was not affected by increasing levels of LPS, the blastocyst rate was reduced in a dose dependent manner (36.69%, 34.21%, 30.35%, 17.27% and 14.03% for the control, 0.01, 0.1, 1 and 10 µg/mL LPS, respectively (P<0.05). These results demonstrate that the developmental competence of ovine oocytes may be affected detrimentally by LPS and such deleterious effects could be related to the maturation process.

Short Exposure to Ethanol Diminishes Caspase-1 and ASC Activation in Human HepG2 Cells In Vitro

This paper discusses how the assembly of pro-caspase-1 and apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) in macromolecular protein complexes, inflammasomes, activates caspase-1. The present study investigates the molecular mechanisms of inflammasome activation in HepG2 cells and examines how short exposures to ethanol (EtOH) affect inflammasome activation. HepG2 cells were treated with lipopolysaccharide (LPS), ATP or nigericin (NIG) in a two-step model. After LPS priming, ATP or NIG were added. As inhibitors, sodium orthovanadate (general inhibitor of tyrosine phosphatases), AC-YVAD-CMK (caspase-1 inhibitor) or AZ10606120 (purinergic receptor P2X7R inhibitor) were applied after LPS priming. To monitor the inflammasome activation, the caspase-1 activity, ASC speck formation, reactive oxygen species (ROS) production and cell death were analyzed. To elucidate the mechanistical approach of EtOH to the inflammasome assembly, the cells were treated with EtOH either under simultaneous LPS administration or concurrently with ATP or NIG application. The co-stimulation with LPS and ATP induced a significant ASC speck formation, caspase-1 activation, cell death and ROS generation. The inhibition of the ATP-dependent purinoreceptor P2X7 decreased the caspase-1 activation, whereas sodium orthovanadate significantly induced caspase-1. Additional treatment with EtOH reversed the LPS and ATP-induced caspase-1 activation, ASC speck formation and ROS production. The ASC speck formation and caspase-1 induction require a two-step signaling with LPS and ATP in HepG2 cells. Inflammasome activation may depend on P2X7. The molecular pathway of an acute effect of EtOH on inflammasomes may involve a reduction in ROS generation, which in turn may increase the activity of tyrosine phosphatases.

Mitigation of Glucolipotoxicity-Induced Apoptosis, Mitochondrial Dysfunction, and Metabolic Stress by N-Acetyl Cysteine in Pancreatic β-Cells

Glucolipotoxicity caused by hyperglycemia and hyperlipidemia are the common features of diabetes-induced complications. Metabolic adaptation, particularly in energy metabolism; mitochondrial dysfunction; and increased inflammatory and oxidative stress responses are considered to be the main characteristics of diabetes and metabolic syndrome. However, due to various fluctuating endogenous and exogenous stimuli, the precise role of these factors under in vivo conditions is not clearly understood. In the present study, we used pancreatic β-cells, Rin-5F, to elucidate the molecular and metabolic changes in glucolipotoxicity. Cells treated with high glucose (25 mM) and high palmitic acid (up to 0.3 mM) for 24 h exhibited increased caspase/poly-ADP ribose polymerase (PARP)-dependent apoptosis followed by DNA fragmentation, alterations in mitochondrial membrane permeability, and bioenergetics, accompanied by alterations in glycolytic and mitochondrial energy metabolism. Our results also demonstrated alterations in the expression of mammalian target of rapamycin (mTOR)/5′ adenosine monophosphate-activated protein kinase (AMPK)-dependent apoptotic and autophagy markers. Furthermore, pre-treatment of cells with 10 mM N-acetyl cysteine attenuated the deleterious effects of high glucose and high palmitic acid with improved cellular functions and survival. These results suggest that the presence of high energy metabolites enhance mitochondrial dysfunction and apoptosis by suppressing autophagy and adapting energy metabolism, mediated, at least in part, via enhanced oxidative DNA damage and mTOR/AMPK-dependent cell signaling.

Leaky-gut enhanced lupus progression in the Fc gamma receptor-IIb deficient and pristane-induced mouse models of lupus

The influence of gut-leakage or gut-microbiota upon lupus progression was explored in 2 lupus mouse models. Pristane, administered in 4-wk-old wild-type (WT) female mice, induced lupus characteristics at 24-wk-old similar to the lupus-onset in FcGRIIb−/− mice. Gut-microbiota alteration was induced by co-housing together with the gavage of feces from 40-wk-old FcGRIIb−/− mice (symptomatic lupus). On the other hand,  gut-leakage was induced  by dextran sulfate solution (DSS). DSS and gut-microbiota alteration induced high serum anti-dsDNA immunoglobulin (Ig) as early as 30 days post-DSS only in FcGRIIb−/− mice. DSS, but not gut-microbiota alteration, enhanced lupus characteristics (serum creatinine and proteinuria) in both lupus models (but not in WT) at 60 days post-DSS. Indeed, DSS induced the translocation of molecular components of gut-pathogens as determined by bacterial burdens in mesenteric lymph node (MLN), endotoxemia (gut-bacterial molecule) and serum (1→3)-β-D-glucan (BG) (gut-fungal molecule) as early as 15 days post-DSS together with enhanced MLN apoptosis in both WT and lupus mice. However, DSS induced spleen apoptosis in FcGRIIb−/− and WT mice at 30 and 60 days post-DSS, respectively, suggesting the higher impact of gut-leakage against spleen of lupus mice. In addition, macrophages preconditioning with LPS plus BG were susceptible to starvation-induced apoptosis, predominantly in FcGRIIb−/− cell, implying the influence of gut-leakage upon cell stress. In summary, gut-leakage induced gut-translocation of organismal-molecules then enhanced the susceptibility of stress-induced apoptosis, predominantly in lupus. Subsequently, the higher burdens of apoptosis in lupus mice increased anti-dsDNA Ig and worsen lupus severity through immune complex deposition. Hence, therapeutic strategies addressing gut-leakage in lupus are interesting.

Augmentation of Glucotoxicity, Oxidative Stress, Apoptosis and Mitochondrial Dysfunction in HepG2 Cells by Palmitic Acid

Hyperglycemia and hyperlipidemia are the hallmarks of diabetes and obesity. Experimental and epidemiological studies have suggested that dietary management and caloric restriction are beneficial in reducing the complications of diabesity. Studies have suggested that increased availability of energy metabolites like glucose and saturated fatty acids induces metabolic, oxidative, and mitochondrial stress, accompanied by inflammation that may lead to chronic complications in diabetes. In the present study, we used human hepatoma HepG2 cells to investigate the effects of high glucose (25 mM) and high palmitic acid (up to 0.3 mM) on metabolic-, inflammatory-, and redox-stress-associated alterations in these cells. Our results showed increased lipid, protein, and DNA damage, leading to caspase-dependent apoptosis and mitochondrial dysfunction. Glucolipotoxicity increased ROS production and redox stress appeared to alter mitochondrial membrane potential and bioenergetics. Our results also demonstrate the enhanced ability of cytochrome P450s-dependent drug metabolism and antioxidant adaptation in HepG2 cells treated with palmitic acid, which was further augmented with high glucose. Altered NF-kB/AMPK/mTOR-dependent cell signaling and inflammatory (IL6/TNF-α) responses were also observed. Our results suggest that the presence of high-energy metabolites enhances apoptosis while suppressing autophagy by inducing inflammatory and oxidative stress responses that may be responsible for alterations in cell signaling and metabolism.

Dual roles of ULK1 (unc-51 like autophagy activating kinase 1) in cytoprotection against lipotoxicity

Saturated fatty acid (SFA)-induced lipotoxicity is caused by the accumulation of reactive oxygen species (ROS), which is associated with damaged mitochondria. Moreover, lipotoxicity is crucial for the progression of nonalcoholic steatohepatitis (NASH). Autophagy is required for the clearance of protein aggregates or damaged mitochondria to maintain cellular metabolic homeostasis. The NFE2L2/NRF2 (nuclear factor, erythroid 2 like 2)-KEAP1 (kelch like ECH associated protein 1) pathway is essential for the elimination of ROS. ULK1 (unc-51 like autophagy activating kinase 1; yeast Atg1) is involved in the initiation of autophagy; however, its role in lipotoxicity-induced cell death in hepatocytes and mouse liver has not been elucidated. We now show that ULK1 potentiates the interaction between KEAP1 and the autophagy adaptor protein SQSTM1/p62, thereby mediating NFE2L2 activation in a manner requiring SQSTM1-dependent autophagic KEAP1 degradation. Furthermore, ULK1 is required for the autophagic removal of damaged mitochondria and to enhance binding between SQSTM1 and PINK1 (PTEN induced kinase 1). This study demonstrates the molecular mechanisms underlying the cytoprotective role of ULK1 against lipotoxicity. Thus, ULK1 could represent a potential therapeutic target for the treatment of NASH.Abbreviations: ACTB: actin beta; CM-H₂DCFDA:5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate; CQ: chloroquine; CUL3: cullin 3; DMSO: dimethyl sulfoxide; GSTA1: glutathione S-transferase A1; HA: hemagglutinin; Hepa1c1c7: mouse hepatoma cells; HMOX1/HO-1: heme oxygenase 1; KEAP1: kelch like ECH associated protein 1; LPS: lipopolysaccharides; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MAPK8/JNK: mitogen-activated protein kinase 8; MEF: mouse embryonic fibroblast; MFN1: mitofusin 1; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; NASH: nonalcoholic steatohepatitis; NFE2L2/NRF2: nuclear factor, erythroid 2 like 2; NQO1: NAD(P)H quinone dehydrogenase 1; PA: palmitic acid; PARP: poly (ADP-ribose) polymerase 1; PINK1: PTEN induced kinase 1; PRKAA1/2: protein kinase AMP-activated catalytic subunits alpha1/2; PRKN/PARK2: parkin RBR E3 ubiquitin protein ligase; PRKC/PKC: protein kinase C; RBX1: ring-box 1; ROS: reactive oxygen species; SFA: saturated fatty acid; siRNA: small interfering RNA; SQSTM1/p62: sequestosome 1; TOMM20: translocase of outer mitochondrial membrane 20; TUBA: tubulin alpha; TUNEL: terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling; ULK1: unc-51 like autophagy activating kinase 1.

New models of lipopolysaccharide-induced implantation loss reveal insights into the inflammatory response

PROBLEM

Chronic endometritis, inflammation of the uterizzvvne lining caused by common gram-negative bacterial strains or mycoplasma, has been associated with unexplained implantation failure and infertility. However, limited models of bacteria-induced implantation loss exist to study the molecular changes that occur in vivo. The goal of this study was to provide a new resource to study the process of bacteria-induced inflammation and implantation loss utilizing common experimental models: C57Bl/6 mice and primary human endometrial stromal cells.

METHOD OF STUDY

Prior to implantation, mated C57Bl/6 females were administered vehicle (saline) or gram-negative bacterial lipopolysaccharide (LPS) at a range of concentrations by intraperitoneal injection. Implantation sites were counted, and uteri were harvested to evaluate the molecular changes that accompany LPS-mediated implantation loss. Primary human endometrial stromal cells were decidualized in vitro in the presence and absence of LPS. Total RNA and conditioned media were harvested to evaluate the expression of known decidualization-associated genes and various cytokines and chemokines.

RESULTS

Lipopolysaccharide treatment resulted in fewer implantation sites in mice, decreased expression of decidualization-associated genes, and altered expression and release of cytokines and chemokines. Immunohistological analysis of the uterus from LPS-exposed mice demonstrated increased apoptosis and decreased proliferation during decidualization.

CONCLUSION

Lipopolysaccharide exposure disrupted implantation and decidualization in mice and human endometrial stromal cells. This model could be used to study the pathophysiology of implantation failure in patients with chronic endometritis or to test potential therapeutic interventions.

Aspirin Inhibits Natural Killer/T-Cell Lymphoma by Modulation of VEGF Expression and Mitochondrial Function

Extranodal nasal-type natural killer/T-cell lymphoma (NKTCL) is an Epstein-Barr virus (EBV)-associated lymphoma with a strong tendency relapse or be refractory in response to chemotherapy. Development of a new strategy for NKTCL treatment is still quite necessary. In this study, we found that aspirin treatment suppresses VEGF expression in NKTCL SNK-6 cells. Further investigation showed that aspirin treatment increases histone methylation in the range of −100~0 that is proximal to the transcription start site on the VEGF promoter, subsequently decreasing the binding ability of Sp1 to the VEGF promoter with VEGF suppression. Furthermore, aspirin treatment modulates mitochondrial function with increased ROS formation and apoptosis in NKTCL cells. Aspirin treatment alone slightly inhibits NKTCL SNK-6 tumor growth and EBV replication; while in the presence of histone deacetylase inhibitor (HDACi) chidamide (CDM), aspirin significantly suppresses the VEGF signaling pathway with increased ROS overgeneration and EBV inhibition. We also showed that with the addition of chidamide, aspirin significantly suppresses NKTCL tumor growth in both in vitro cell culture and in vivo mouse model with prolonged mouse survival. This is the first time that the potential mechanism for aspirin-mediated VEGF suppression and anti-tumor effect has been discovered, and this study provides a new strategy for anti-tumor drug development for NKTCL treatment based on aspirin-mediated targeting of the VEGF signaling pathway and ROS formation.

N-Acetylcysteine alleviates gut dysbiosis and glucose metabolic disorder in high-fat diet-fed mice

BACKGROUND

N-Acetylcysteine (NAC), an antioxidative reagent for clinical diseases, shows potential in the treatment of diabetes and other metabolic diseases. However, it is unknown how NAC modulates the gut microbiota of mice with metabolic syndrome. The aim of the present study was to demonstrate the preventive effect of NAC on intestinal dysbiosis and glucose metabolic disorder.

METHODS

Mice (C57BL/6J strain) were fed either a normal chow diet (NCD), NCD plus NAC, a high-fat diet (HFD), or HFD plus NAC for 5 months, after which glucose levels, circulating endotoxins and key metabolism-related proteins were determined. Fecal samples were analyzed by 16S rRNA sequencing. A novel analysis was performed to predict functional changes in gut microbiota. In addition, Spearman's correlation analysis was performed between metabolic biomarkers and bacterial abundance.

RESULTS

Treatment with NAC significantly reversed the glucose intolerance, fasting glucose concentrations, and gains in body weight and plasma endotoxin in HFD-fed mice. Further, NAC upregulated occludin and mucin glycoprotein levels in the proximal colon of HFD-treated mice. Noticeably, NAC promoted the growth of beneficial bacteria (i.e. Akkermansia, Bifidobacterium, Lactobacillus and Allobaculum) and decreased populations of diabetes-related genera, including Desulfovibrio and Blautia. In addition, NAC may affect the metabolic pathways of intestinal bacteria, including lipopolysaccharide biosynthesis, oxidative stress, and bacterial motility. Finally, the modified gut microbiota was closely associated with the metabolic changes in NAC-treated HFD-fed mice.

CONCLUSIONS

N-Acetylcysteine may be a potential drug to prevent glucose metabolic disturbances by reshaping the structure of the gut microbiota.

Reduction in the Level of Plasma Mitochondrial DNA in Human Diving, Followed by an Increase in the Event of an Accident

Circulating mitochondrial DNA (mtDNA) is receiving increasing attention as a danger-associated molecular pattern in conditions such as autoimmunity or trauma. In the context of decompression sickness (DCS), the course of which is sometimes erratic, we hypothesize that mtDNA plays a not insignificant role particularly in neurological type accidents. This study is based on the comparison of circulating mtDNA levels in humans presenting with various types of diving accidents, and punctured upon their admission at the hyperbaric facility. One hundred and fourteen volunteers took part in the study. According to the clinical criteria there were 12 Cerebro DCS, 57 Medullary DCS, 15 Vestibular DCS, 8 Ctrl+ (accident-free divers), and 22 Ctrl- (non-divers). This work demonstrates that accident-free divers have less mtDNA than non-divers, which leads to the assumption that hyperbaric exposure degrades the mtDNA. mtDNA levels are on average greater in divers with DCS compared with accident-free divers. On another hand, the amount of double strand DNA (dsDNA) is neither significantly different between controls, nor between the different DCS types. Initially the increase in circulating oligonucleotides was attributed to the destruction of cells by bubble abrasion following necrotic phenomena. If there really is a significant difference between the Medullary DCS and the Ctrl-, this difference is not significant between these same DCS and the Ctrl+. This refutes the idea of massive degassing and suggests the need for new research in order to verify that oxidative stress could be a key element without necessarily being sufficient for the occurrence of a neurological type of accident.

Detrimental effects of lipopolysaccharides on maturation of bovine oocytes

Objective

Gram-negative bacteria lipopolysaccharide (LPS) has been reported to be associated with uterine impairment, embryonic resorption, ovarian dysfunction, and follicle retardation. Here, we aimed to investigate the toxic effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes.

Methods

First, we developed an in vitro model to study the response of bovine cumulus-oocyte complexes (COCs) to LPS stress. After incubating germinal vesicle COCs in 10 μg/mL of LPS, we analyzed the following three aspects: the expression levels of the LPS receptor toll-like receptor 4 (TLR4) in COCs, activities of intracellular signaling protein p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-κB); and the concentrations of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6. Furthermore, we determined the effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes.

Results

The results revealed that LPS treatment significantly elevated TLR4 mRNA and protein expression levels in COCs. Exposure of COCs to LPS also resulted in a marked increase in activity of the intracellular signaling protein p-p38 MAPK and NF-κB. Furthermore, oocytes cultured in maturation medium containing LPS had significantly higher concentrations of the proinflammatory cytokines IL-1β, TNF-α, and IL-6. LPS exposure significantly decreased the first polar body extrusion rate. The cytoplasmic maturation, characterized by polar body extrusion and distribution of peripheral cortical granules, was significantly impaired in LPS-treated oocytes. Moreover, LPS exposure significantly increased intracellular reactive oxygen species levels and the relative mRNA abundance of the antioxidants thioredoxin (Trx), Trx2, and peroxiredoxin 1 in oocytes. Moreover, the early apoptotic rate and the release of cytochrome C were significantly increased in response to LPS. The cleavage, morula, and blastocyst formation rates were significantly lower in parthenogenetically activated oocytes exposed to LPS, while the incidence of apoptotic nuclei in blastocysts was significantly increased.

Conclusion

Together, these results provide an underlying mechanism by which LPS impairs maturation potential in bovine oocytes.

Functional impairment triggered by altertoxin II (ATXII) in intestinal cells in vitro: cross-talk between cytotoxicity and mechanotransduction

Intestinal cells are able to continuously integrate response to multiple stimuli/stressors; these include the concomitant activation of “chemically driven” pathways, of paramount importance in the response to toxicants, as well as physical stimulation derived from motility. Altertoxin II (ATXII, 0.1, 1 and 10 µM), a mycotoxin produced by the food contaminant fungus Alternaria alternata was studied in HT-29 intestinal adenocarcinoma cells and in non-transformed intestinal epithelial cells, HCEC. One-hour incubation with ATXII was sufficient to trigger irreversible cytotoxicity in both cell types, as well as to modify cellular responses to concomitant pro-oxidant challenge (H₂O₂, 100–500 µM, DCF-DA assay) suggesting that even relatively short-time exposure of the intestinal cells could be sufficient to alter their functionality. Combination of ATXII (1 µM) with physical stimulation typical of the intestinal compartment (shear stress) revealed differential response of tumor-derived epithelial cells HT-29 in comparison to HCEC, in particular in the localization of the transcription factor Nrf2 (NF-E2-related factor 2). Moreover, ATXII reduced the migratory potential of HCEC as well as their membrane fluidity, but had no respective impact on HT-29 cells. Taken together, ATXII appeared to alter predominantly membrane functionality in HCEC thus hampering crucial functions for cellular motility/turnover, as well as barrier function of healthy intestinal cells and had very limited activity on the tumor counterparts.

Sidr Kashmiry honey and its fractions induced apoptosis in hepatocellular carcinoma in vitro

Positive evidence for anticancer activities of honey is growing and the mechanism on how honey has anticancer characteristics is an area of great interest. Honey has been studied in various cancer cell lines for its ability to induce apoptosis, with several mechanisms of action being suggested. This study aims to evaluate the apoptotic activity of the non cytotoxic Sidr Kashmiry honey and its residue of successive fractionation as well as the cytotoxic chloroform-methanol and ethyl acetate fractions against hepatocellular carcinoma cells in vitro. Apoptosis was assessed by DNA fragmentation, diphenyl amine assay, and ultrastructure investigation. Micronuclei test was carried out to assess genotoxicity. Crude honey, residue, ethyl acetate and chloroform-methanol induced apoptosis, however, the residue and ethyl acetate caused high genotoxicity. Non cytotoxic Sidr Kashmiry honey and its cytotoxic chloroform-methanol fraction could be a powerful pro-apoptotic and non-genotoxic anticancer agent.

Impaired Cell Viability and Functionality of Hepatocytes After Incubation With Septic Plasma-Results of a Second Prospective Biosensor Study

Liver dysfunction (LD) and liver failure are associated with poor outcome in critically ill patients. In patients with severe sepsis or septic shock, LD occurred in nearly 19% of patients. An early diagnosis of LD at time of initial damage of the liver can lead to a better prognosis of these patients because an early start of therapy is possible. We performed a second prospective study with septic patients to test a new cell-based cytotoxicity device (biosensor) to evaluate clinical relevance for early diagnosis of LD and prognostic capacity. In the clinical study, 99 intensive care unit patients were included in two groups. From the patients of the septic group (n = 51, SG), and the control (non-septic) group [n = 49, control group (CG)] were drawn 20 ml blood at inclusion, after 3, and 7 days for testing with the biosensor. Patients’ data were recorded for hospital survival, organ function, and demographic data, illness severity [acute physiology and chronic health evaluation (APACHE) II-, sepsis-related organ failure assessment (SOFA) scores], cytokines, circulating-free deoxyribonucleic acid/neutrophil-derived extracellular traps (cf-DNA/NETs), microbiological results, and pre-morbidity. For the developed cytotoxicity test, the human liver cell line HepG2/C3A was used. Patients’ plasma was incubated in a microtiter plate assay with the test cells and after 6 days incubation the viability (trypan blue staining, XTT-test) and functionality (synthesis of albumin, cytochrome 1A2 activity) was analyzed. An impairment of viability and functionality of test cells was only seen in the SG compared with the CG. The plasma of non-survivors in the SG led to a more pronounced impairment of test cells than the plasma of survivors at inclusion. In addition, the levels of cf-DNA/NETs were significantly higher in the SG at inclusion, after 3, and after 7 days compared with the CG. The SG showed an in-hospital mortality of 24% and the values of bilirubin, APACHE II-, and SOFA scores were markedly higher at inclusion than in the CG. Hepatotoxicity of septic plasma was already detected with the liver cell-based biosensor at inclusion and also in the course of disease. The biosensor may be a tool for early diagnosis of LD in septic patients and may have prognostic relevance.

The in vitro effects of macrophages on the osteogenic capabilities of MC3T3-E1 cells encapsulated in a biomimetic poly(ethylene glycol) hydrogel

Poly(ethylene glycol) PEG-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in vivo. The goal of this study was to investigate the impact of the FBR, and specifically the presence of inflammatory macrophages, on encapsulated cells and their ability to synthesize new extracellular matrix. This study employed an in vitro co-culture system with murine macrophages and MC3T3-E1 pre-osteoblasts encapsulated in a bone-mimetic hydrogel, which were cultured in transwell inserts, and exposed to an inflammatory stimulant, lipopolysaccharide (LPS). The co-culture was compared to mono-cultures of the cell-laden hydrogels alone and with LPS over 28 days. Two macrophage cell sources, RAW 264.7 and primary derived, were investigated. The presence of LPS-stimulated primary macrophages led to significant changes in the cell-laden hydrogel by a 5.3-fold increase in percent apoptotic osteoblasts at day 28, 4.2-fold decrease in alkaline phosphatase activity at day 10, and 7-fold decrease in collagen deposition. The presence of LPS-stimulated RAW macrophages led to significant changes in the cell-laden hydrogel by 5-fold decrease in alkaline phosphatase activity at day 10 and 4-fold decrease in collagen deposition. Mineralization, as measured by von Kossa stain or quantified by calcium content, was not sensitive to macrophages or LPS. Elevated interleukin-6 and tumor necrosis factor-α secretion were detected in mono-cultures with LPS and co-cultures. Overall, primary macrophages had a more severe inhibitory effect on osteoblast differentiation than the macrophage cell line, with greater apoptosis and collagen I reduction. In summary, this study highlights the detrimental effects of macrophages on encapsulated cells for bone tissue engineering.

STATEMENT OF SIGNIFICANCE

Poly(ethylene glycol) (PEG)-based hydrogels are promising for cell encapsulation and tissue engineering, but are known to elicit a foreign body response (FBR) in vivo. The impact of the FBR on encapsulated cells and their ability to synthesize tissue has not been well studied. This study utilizes thiol-ene click chemistry to create a biomimetic, enzymatically degradable hydrogel system with which to encapsulate MC3T3-E1 pre-osteoblasts. The osteogenic capabilities and differentiation of these cellswerestudied in co-culture with macrophages, known drivers of the FBR.This study demonstrates that macrophages reduce osteogenic capabilities of encapsulated cellsin vitroand suggestthat the FBR should be considered for in vivo tissue engineering.

N-Acetyl-l-Cysteine treatment efficiently prevented pre-diabetes and inflamed-dysmetabolic liver development in hypothalamic obese rats

AIM

Hypothalamic obese rats are characterized by pre-diabetes, dyslipidemia, hyperadiposity, inflammation and, liver dysmetabolism with oxidative stress (OS), among others. We studied endocrine-metabolic dysfunctions and, liver OS and inflammation in both monosodium l-glutamate (MSG)-neonatally damaged and control litter-mate (C) adult male rats, either chronically treated with N-Acetyl-l-Cysteine since weaned (C-NAC and MSG-NAC) or not.

METHODOLOGY

We evaluated circulating TBARS, glucose, insulin, triglycerides, uric acid (UA) and, aspartate and alanine amino-transferase; insulin sensitivity markers (HOMA indexes, Liver Index of Insulin Sensitivity -LISI-) were calculated and liver steps of the insulin-signaling pathway were investigated. Additionally, we monitored liver OS (protein carbonyl groups, GSH and iNOS level) and inflammation-related markers (COX-2 and TNFα protein content; gene expression level of Il1b, Tnfα and Pai-1); and carbohydrate and lipid metabolic functions (glucokinase/fructokinase activities and, mRNA levels of Srebp1c, Fas and Gpat).

KEY FINDINGS

Chronic NAC treatment in MSG rats efficiently decreased the high circulating levels of triglycerides, UA, transaminases and TBARS, as well as peripheral (high insulinemia and HOMA indexes) and liver (LISI and the P-AKT:AKT and P-eNOS:eNOS protein ratio values) insulin-resistance. Moreover, NAC therapy in MSG rats prevented liver dysmetabolism by decreasing local levels of OS and inflammation markers. Finally, NAC-treated MSG rats retained normal liver glucokinase and fructokinase activities, and Srebp1c, Fas and Gpat (lipogenic genes) expression levels.

SIGNIFICANCE

Our study strongly supports that chronic oral antioxidant therapy (NAC administration) prevented the development of pre-diabetes, dyslipidemia, and inflamed-dysmetabolic liver in hypothalamic obese rats by efficiently decreasing high endogenous OS.

Effects of lipopolysaccharide on maturation of bovine oocyte in vitro and its possible mechanisms

Lipopolysaccharide disturbs the secretion of gonadotropin, endometrial function and implantation efficiency. However, there is little information regarding the effects of lipopolysaccharide on cyclic ovary activity, especially oocyte maturation. Therefore, we aimed to investigate the effects of lipopolysaccharide on the maturation potential of bovine oocytes. We found that lipopolysaccharide exposure significantly decreased the first polar body extrusion rate and delayed the cell cycle progression. The abnormal spindle rate was significantly increased in lipopolysaccharide treatment group, accompanied by disrupted localization and level of phosphorylated mitogen-activated protein kinase (p-MAPK). Moreover, lipopolysaccharide treatment significantly increased intracellular reactive oxygen species (ROS) levels and the early apoptotic rate in oocytes. The pro-apoptotic caspase-3 and Bax mRNA levels and caspase-3 protein level were significantly increased, whereas the anti-apoptotic Bcl-2 and XIAP transcript abundance were significantly decreased in lipopolysaccharide exposure group. Furthermore, the dimethyl-histone H3 lysine 4 (H3K4me2) level was significantly increased, while the DNA methylation (5-mC) and dimethyl-histone H3 lysine 9 (H3K9me2) levels were markedly decreased in oocytes treated with lipopolysaccharide. In conclusion, lipopolysaccharide exposure inhibits the maturation potential of bovine oocytes by affecting cell cycle, cytoskeletal dynamics, oxidative stress, and epigenetic modifications.

Elucidation of Molecular Mechanisms of Streptozotocin-Induced Oxidative Stress, Apoptosis, and Mitochondrial Dysfunction in Rin-5F Pancreatic β-Cells

Streptozotocin is a pancreatic beta-cell-specific cytotoxin and is widely used to induce experimental type 1 diabetes in rodent models. The precise molecular mechanism of STZ cytotoxicity is however not clear. Studies have suggested that STZ is preferably absorbed by insulin-secreting β-cells and induces cytotoxicity by producing reactive oxygen species/reactive nitrogen species (ROS/RNS). In the present study, we have investigated the mechanism of cytotoxicity of STZ in insulin-secreting pancreatic cancer cells (Rin-5F) at different doses and time intervals. Cell viability, apoptosis, oxidative stress, and mitochondrial bioenergetics were studied. Our results showed that STZ induces alterations in glutathione homeostasis and inhibited the activities of the respiratory enzymes, resulting in inhibition of ATP synthesis. Apoptosis was observed in a dose- and time-dependent manner. Western blot analysis has also confirmed altered expression of oxidative stress markers (e.g., NOS and Nrf2), cell signaling kinases, apoptotic protein-like caspase-3, PARP, and mitochondrial specific proteins. These results suggest that STZ-induced cytotoxicity in pancreatic cells is mediated by an increase in oxidative stress, alterations in cellular metabolism, and mitochondrial dysfunction. This study may be significant in better understanding the mechanism of STZ-induced β-cell toxicity/resistance and the etiology of type 1 diabetes induction.

Atrazine triggers hepatic oxidative stress and apoptosis in quails (Coturnix C. coturnix) via blocking Nrf2-mediated defense response

The bioaccumulation and environmental persistence of atrazine (ATZ) poses a severe hazard to animal ecosystem. Quail has strong sensitivity to environmental pollutant, thus it is one of the most important ecological pollution indicator. However, true proof for the effects of ATZ exposure on the liver of quails is lacking. To evaluate the liver injury and the role of Nrf2-mediated defense responses during ATZ exposure, male quails were treated with ATZ (0, 50, 250 and 500mg/kg) by oral gavage for 45 days. Histopathological and ultrastructural changes, oxidative stress indices, apoptosis-related factors and Nrf2 pathway were detected. ATZ caused irreparable mitochondrial damage and destroyed morphophysiological integrity of the quail liver. Lower level ATZ (<250mg/kg) activated Nrf2 signaling pathway to protect liver against oxidative stress and apoptosis via enhancing antioxidative activity. Higher level ATZ (>500mg/kg) induced oxidative stress and apoptosis through decrease of non-enzymatic antioxidant, antioxidant enzymes and anti-apoptosis factors and increase of apoptosis factors expressions. Taken together, our results suggested that ATZ-induced hepatotoxicity in quails was associated with blocking Nrf2-mediated defense response.