Free Lipid Research Articles

Quercetin Inhibits Neuronal Pyroptosis and Ferroptosis by Modulating Microglial M1/M2 Polarization in Atherosclerosis.

Atherosclerosis (AS) with iron and lipid overload and systemic inflammation is a risk factor for Alzheimer's disease. M1 macrophage/microglia participate in neuronal pyroptosis and recently have been reported to be the ferroptosis-resistant phenotype. Quercetin plays a prominent role in preventing and treating neuroinflammation, but the protective mechanism against neurodegeneration caused by iron deposition is poorly understood. ApoE-/- mice were fed a high-fat diet with or without quercetin treatment. The Morris water maze and novel object recognition tests were conducted to assess spatial learning and memory, and nonspatial recognition memory, respectively. Prussian blue and immunofluorescence staining were performed to assess the iron levels in the whole brain and in microglia, microglia polarization, and the degree of microglia/neuron ferroptosis. In vitro, we further explored the molecular biological alterations associated with microglial polarization, neuronal pyroptosis, and ferroptosis via Western blot, flow cytometry, CCK8, LDH, propidium iodide, and coculture system. We found that quercetin improved brain lesions and spatial learning and memory in AS mice. Iron deposition in the whole brain or microglia was reversed by the quercetin treatment. In the AS group, the colocalization of iNOS with Iba1 was increased, which was reversed by quercetin. However, the colocalization of iNOS with PTGS2/TfR was not increased in the AS group, suggesting a character resisting ferroptosis. Quercetin induced the expression of Arg-1 and decreased the colocalizations of Arg-1 with PTGS2/TfR. In vitro, ox-LDL combined with ferric ammonium citrate treatment (OF) significantly shifted the microglial M1/M2 phenotype balance and increased the levels of free iron, ROS, and lipid peroxides, which was reversed by quercetin. M1 phenotype induced by OF caused neuronal pyroptosis and was promoted to ferroptosis by L-NIL treatment, which contributed to neuronal ferroptosis as well. However, quercetin induced the M1 to M2 phenotype and inhibited M2 macrophages/microglia and neuron pyroptosis or ferroptosis. In summary, quercetin alleviated neuroinflammation by inducing the M1 to M2 phenotype to inhibit neuronal pyroptosis and protected neurons from ferroptosis, which may provide a new idea for neuroinflammation prevention and treatment.

Effect of quercetin and mirtazapine on spermatogenesis and testis structure in phenylhydrazine-induced hemolytic anemia mice: An experimental study

Anemia poses a significant healthcare challenge across different socioeconomic groups and can result in reproductive system damage through the generation of free radicals and lipid peroxidation. This study examines the protective effects of quercetin (QUE) and mirtazapine (MIR) against the reproductive damage caused by phenylhydrazine (PHZ) in mice. Fifty NMRI mice, aged 8–10 weeks with an average weight of 27.0 ± 2.0 g, were randomly divided into five groups. The control group (Group 1) received oral administration of 10 mL/kg/day of normal saline. Group 2 (PHZ group) received an initial intraperitoneal dose of 8 mg/100 g body weight of PHZ, followed by subsequent doses of 6 mg/100 g every 48 h. Group 3 received PHZ along with oral QUE at a dosage of 50 mg/kg/day. Group 4 received PHZ along with oral MIR at a dosage of 30 mg/kg/day. Group 5 received PHZ along with oral QUE at a dosage of 50 mg/kg/day and MIR at a dosage of 30 mg/kg/day. The treatment duration was 35 days. Sperm samples were collected from the caudal region of the epididymis post-euthanasia to assess the total mean sperm count, sperm viability, motility, DNA damage, and morphology. Testicular tissue was employed to quantify total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) concentrations, while serum levels of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were analyzed. Additionally, various aspects, including testicular histopathology, oxidative enzyme levels, gene expression related to apoptosis and antiapoptotic pathways, and in vivo fertility index, were evaluated after 35 days. The QUE, MIR, and QUE + MIR groups showed less abnormal morphology and DNA damage, as well as better total and progressive sperm motility, motility characteristics, viability, and plasma membrane function compared to the PHZ group. QUE, MIR, and QUE + MIR administration increased TAC, SOD, and GPx activities in testicular tissue, while reducing MDA levels compared to the PHZ group. Furthermore, QUE, MIR, and QUE + MIR significantly reduced Bax, and caspase-3 expression levels, and increased Bcl-2 expression levels, compared to the PHZ group. Mice treated with QUE, MIR, and QUE + MIR exhibited an increased in vivo fertility index and plasma sex hormone levels compared to the PHZ group. These results show that QUE, MIR, and QUE + MIR might be able to improve the fertility index, boost the testicular antioxidant defense system, and control the death of germ cells. This could mean that they could be used to treat mice with PHZ-induced testicular damage.

Extrusion-controlled lipid retention and distribution of wheat germ and its application combining exogenous starch

Wheat germ is an agricultural but low-economic by-product for animal feed or waste due to its susceptibility of hydrolytic/oxidative rancidities. Here, we use controllable extrusion to treat wheat germ, and with assistance of exogenous starch as lipid protective factor at different ratios (0:10 2:8, 3:7, 4:6). Oxidation of optimized germ extrudate was slowed down during storage, with total lipid retention rate reach up to ∼88.3%. Extrusion dynamic analysis showed that relatively high screw speed (100–150 rpm) significantly shortened mean residence time, increased axial diffusion velocity and reduced the loss of free and bound lipid. Type Ⅱ starch-lipid complex was changed to type Ⅰ during extrusion, with thermal transition peak declined. Wheat germ lipid was most evenly distributed under 100 rpm extrusion. The hydrogen bonding interaction between exogenous starch and lipids in wheat germ was strengthened, with significant modification in water absorption, water solubility, expansion and textual indexes.

Human mesenchymal stem cells derived exosomes improve ovarian function in chemotherapy-induced premature ovarian insufficiency mice by inhibiting ferroptosis through Nrf2/GPX4 pathway.

Chemotherapy exposure has become a main cause of premature ovarian insufficiency (POI). This study aimed to evaluate the role and molecular mechanism of human umbilical cord mesenchymal stem cell-derived exosomes (hUMSC-Exos) in ovarian function protection after chemotherapy. hUMSC-Exos were applied to cyclophosphamide-induced premature ovarian insufficiency mice and human ovarian granulosa tumor cells (KGN) to determine their effects on follicular development and granulosa cell apoptosis. Evaluation was done for iron ion and reactive oxygen species (ROS) production, lipid peroxidation levels, and changes in iron death-related molecules (nuclear factor (erythroid-derived 2)-like 2 (Nrf2), Glutathione Peroxidase enzyme 4 (GPX4), and Solute carrier family 7 member 11 cystine glutamate transporter (SLC7A11; xCT)). Furthermore, rescue experiments using an Nrf2 inhibitor were performed to assess the therapeutic effects of hUMSC-Exos on granulosa cells. hUMSC-Exos promoted ovarian hormone levels and primary follicle development in POI mice and reduced granulosa cell apoptosis. After hUMSC-Exos treatment, the ROS production, free iron ions and lipid peroxidation levels of granulosa cells decreased, and the iron death marker proteins Nrf2, xCT and GPX4 also decreased. Furthermore, the Nrf2 inhibitor ML385 significantly attenuated the effects of hUMSC-Exos on granulosa cells. hUMSC-Exos inhibit ferroptosis and protect against CTX-induced ovarian damage and granulosa cell apoptosis through the Nrf2/GPX4 signaling pathway, revealing a novel mechanism of hUMSC-Exos in POI therapy.

Structural characterization of fatty acid anions via gas-phase charge inversion using Mg(tri-butyl-terpyridine)2 2+ reagent ions.

Free fatty acids and lipid classes containing fatty acid esters are major components of lipidome. In the absence of a chemical derivatization step, FA anions do not yield all of the structural information that may be of interest under commonly used collision-induced dissociation (CID) conditions. A line of work that avoids condensed-phase derivatization takes advantage of gas-phase ion/ion chemistry to charge invert FA anions to an ion type that provides the structural information of interest using conventional CID. This work was motivated by the potential for significant improvement in overall efficiency for obtaining FA chain structural information. A hybrid triple quadrupole/linear ion-trap tandem mass spectrometer that has been modified to enable the execution of ion/ion reaction experiments was used to evaluate the use of 4,4',4″-tri-tert-butyl-2,2':6',2″-terpyridine (ttb-Terpy) as the ligand in divalent magnesium complexes for charge inversion of FA anions. Mg(ttb-Terpy)2 2+ complexes provide significantly improved efficiency in producing structurally informative products from FA ions relative to Mg(Terpy)2 2+ complexes, as demonstrated for straight-chain FAs, branched-chain FAs, unsaturated FAs, and cyclopropane-containing FAs. It was discovered that most of the structurally informative fragmentation from [FA-H + Mg(ttb-Terpy)]+ results from the loss of a methyl radical from the ligand followed by radical-directed dissociation (RDD), which stands in contrast to the charge-remote fragmentation (CRF) believed to be operative with the [FA-H + Mg(Terpy)]+ ions. This work demonstrates that a large fraction of product ions from the CID of ions of the form [FA-H + Mg(ttb-Terpy)]+ are derived from RDD of the FA backbone, with a very minor fraction arising from structurally uninformative dissociation channels. This ligand provides an alternative to previously used ligands for the structural characterization of FAs via CRF.

Effect of salting and dehydration treatments on the physicochemical and gel properties of hen and duck egg yolks, plasma and granules.

Salted hen egg yolks are less oily and less flavorful than salted duck egg yolks. However, hen eggs have a more adequate market supply and have a broader application prospect than duck eggs. In the present study, egg yolks, plasma, and granules were dehydrated by adding 1% NaCl to simulate traditional curing process of salted egg yolk. The changes in the pickling process of hen egg yolks (HEY) and duck egg yolks (DEY) plasma and granules were compared to reveal the gelation mechanism and the underlying causes of quality differences in salted HEY and DEY. Salted HEY can be compared with the changes in DEY during the pickling process to provide a theoretical basis for the quality improvement of salted HEY to salted DEY. The results showed that both plasma and granules were involved in gel formation, but exhibited different aggregation behaviors. Based on the intermolecular forces, the HEY proteins achieved aggregation mainly through hydrophobic interactions and DEY proteins mainly through covalent binding. According to spin-spin relaxation time, HEY gels immobilized a large amount of lipid and interacted strongly with lipids. DEY gels showed much free lipid and had weak interaction with lipid. The microstructure showed that HEY proteins were easily unfolded to form a homogeneous three-dimensional gel network structure after salting, whereas heterogeneous aggregates were formed to hinder the gel development in DEY. Changes in protein secondary structure content showed that pickling can promote the transformation of the α-helices to β-sheets structure in HEY gels, whereas more α-helices structure was formed in DEY gels. The present study has demonstrated that different gelation behaviors of hen and duck egg yolk proteins (especially in plasma) through salting treatment led to the difference in the quality of salted HEY and DEY. © 2024 Society of Chemical Industry.

Juglone induces ferroptosis in glioblastoma cells by inhibiting the Nrf2-GPX4 axis through the phosphorylation of p38MAPK

BackgroundFerroptosis, a non-apoptotic form of cell death induced by accumulation of free iron ions and lipid peroxidation, its importance for cancer treatment is gradually being recognized. Research on the anti-cancer mechanism of juglone is accumulating. However, the specific mechanism by which it directs glioblastoma (GBM) to death is unknown.MethodsWe used in vitro and in vivo experiments to explore the anti-GBM effect generated by juglone through the ferroptosis pathway.ResultsJuglone mainly causes cell death by inducing ferroptosis. Mechanistically, juglone can significantly activate the phosphorylation of p38MAPK. According to transcriptome sequencing and protein interaction analysis, the Nrf2-GPX4 signaling pathway is identified as the primary pathway through which juglone mediates ferroptosis. In vitro and in vivo experiments further verified that juglone induces the ferroptosis of GBM by activating the phosphorylation of p38MAPK and negatively regulating the Nrf2-GPX4 signaling pathway.ConclusionJuglone induces ferroptosis and inhibits the growth of GBM by targeting the Nrf2/Gpx4 signaling pathway and thus holds promise as a novel ferroptosis inducer or anti-GBM drug.

Phytochemical compounds and antioxidant capacities of Abelmoschus manihot leaf extracts using different solvents

Abstract. Winata GM, Hardinsyah H, Marliyati SA, Rimbawan R, Andrianto D. 2024. Phytochemical compounds and antioxidant capacities of Abelmoschus manihot leaf extracts using different solvents. Biodiversitas 25: 942-949. Gedi (Abelmoschus manihot (L.) Medik) leaves are popularly consumed as a green vegetable by Eastern Indonesians. This work aimed to carry out the phytochemical compounds and antioxidant capacities of five extracts, i.e., water, 70% ethanol, absolute ethanol, ethyl acetate, and hexane of Abelmoschus manihot leaf. Qualitative analysis was done as a preliminary screening for flavonoid, tannin, saponin, alkaloid, triterpenoid, steroid, and quinone. Quantitative analysis determined the flavonoid, phenolic, tannin, quercetin, and steroid content. In-vitro antioxidant analysis was conducted to determine free radical scavenging activity and lipid peroxidation inhibitory activity. The results showed that flavonoid was only found in 70% ethanol extract; steroid was obtained in all extracts, while alkaloid, saponin, tannin, quinone, and triterpenoid were absent in all extracts. The results of the quantitative analysis showed that the highest flavonoid was in 70% ethanol extract (39.2 mg GAE/g), phenolic in ethyl acetate extract (34.792 mg QE/g), tannin in 70% ethanol (1.395 mg/g), quercetin in absolute ethanol extract (0.246 mg/g), and steroid content in hexane extract (201.948 mg/g). Half maximal inhibitory concentration (IC50) of each extract to inhibit malondialdehyde (MDA) formation was lower than free radical scavenging activity. The IC50 values of MDA formation in absolute ethanol and hexane extracts were 6.77 ppm and 7.67 ppm, respectively. The IC50 of vitamin E was 3.67 ppm. Further study is needed to determine the mechanism of Abelmoschus manihot leaf extracts as antioxidants used as a functional food.

TIGAR reduces neuronal ferroptosis by inhibiting succinate dehydrogenase activity in cerebral ischemia

Ischemia Stroke (IS) is an acute neurological condition with high morbidity, disability, and mortality due to a severe reduction in local cerebral blood flow to the brain and blockage of oxygen and glucose supply. Oxidative stress induced by IS predisposes neurons to ferroptosis. TP53-induced glycolysis and apoptosis regulator (TIGAR) inhibits the intracellular glycolytic pathway to increase pentose phosphate pathway (PPP) flux, promotes NADPH production and thus generates reduced glutathione (GSH) to scavenge reactive oxygen species (ROS), and thus shows strong antioxidant effects to ameliorate cerebral ischemia/reperfusion injury. However, in the current study, prolonged ischemia impaired the PPP, and TIGAR was unable to produce NADPH but was still able to reduce neuronal ferroptosis and attenuate ischemic brain injury. Ferroptosis is a form of cell death caused by free radical-driven lipid peroxidation, and the vast majority of ROS leading to oxidative stress are generated by mitochondrial succinate dehydrogenase (SDH) driving reverse electron transfer (RET) via the mitochondrial electron transport chain. Overexpression of TIGAR significantly inhibited hypoxia-induced enhancement of SDH activity, and TIGAR deficiency further enhanced SDH activity. We also found that the inhibitory effect of TIGAR on SDH activity was related to its mitochondrial translocation under hypoxic conditions. TIGAR may inhibit SDH activity by mediating post-translational modifications (acetylation and succinylation) of SDH A through interaction with SDH A. SDH activity inhibition reduces neuronal ferroptosis by decreasing ROS production, eliminating MitoROS levels and attenuating lipid peroxide accumulation. Notably, TIGAR-mediated inhibition of SDH activity and ferroptosis was not dependent on the PPP-NADPH-GPX4 pathways. In conclusion, mitochondrial translocation of TIGAR in prolonged ischemia is an important pathway to reduce neuronal ferroptosis and provide sustainable antioxidant defense for the brain under prolonged ischemia, further complementing the mechanism of TIGAR resistance to oxidative stress induced by IS.

Large flour aggregates containing ordered B + V starch crystals significantly improved the digestion resistance of starch in pretreated multigrain flour

The starch digestibility of flour is influenced by both physicochemical treatment and flour particle size, but the interactive effect of these two factors is still unclear. In this study, the effect of pullulanase debranching, combined with heat-moisture treatment (P-HMT), on starch digestibility of multi-grain flours (including oat, buckwheat and wheat) differing in particle size was investigated. The results showed that the larger-size flour always resulted in a higher resistant starch (RS) content either in natural or treated multi-grain flour (NMF or PHF). P-HMT doubled the RS content in NMFs and the large-size PHF yielded the highest RS content (78.43 %). In NMFs, the cell wall integrity and flour particle size were positively related to starch anti-digestibility. P-HMT caused the destruction of cell walls and starch granules, as well as the formation of rigid flour aggregates with B + V starch crystallite. The largest flour aggregates with the most ordered B + V starch were found in large-size PHF, which contributed to its highest RS yield, while the medium- and small-size PHFs with smaller aggregates were sensitive to P-HMT, resulting in the lower ordered starch but stronger interactions between starch and free lipid or monomeric proteins, eventually leading to their lower RS but higher SDS yield.

Intraperitoneally injected d11-11(12)-epoxyeicosatrienoic acid is rapidly incorporated and esterified within rat plasma and peripheral tissues but not the brain

Epoxyeicosatrienoic acids (EpETrEs) are bioactive lipid mediators of arachidonic acid cytochrome P450 oxidation. In vivo, the free (unbound) form of EpETrEs regulate multiple processes including blood flow, angiogenesis and inflammation resolution. Free EpETrEs are thought to rapidly degrade via soluble epoxide hydrolase (sEH); yet, in many tissues, the majority of EpETrEs are esterified to complex lipids (e.g. phospholipids) suggesting that esterification may play a major role in regulating free, bioactive EpETrE levels. This hypothesis was tested by quantifying the metabolism of intraperitoneally injected free d11-11(12)-Epoxyeicosatrienoic acid (d11-11(12)-EpETrE) in male and female rats. Plasma and tissues (liver, adipose and brain) were obtained 3 to 4 min later and assayed for d11-11(12)-EpETrE and its sEH metabolite, d11-11,12-dihydroxyeicosatrienoic acid (d11-11,12-diHETrE) in both the free and esterified lipid fractions. In both males and females, the majority of injected tracer was recovered in liver followed by plasma and adipose. No tracer was detected in the brain, indicating that brain levels are maintained by endogenous synthesis from precursor fatty acids. In plasma, liver, and adipose, the majority (>54 %) of d11-11(12)-EpETrE was found esterified to phospholipids or neutral lipids (triglycerides and cholesteryl esters). sEH-derived d11-11,12-diHETrE was not detected in plasma or tissues, suggesting negligible conversion within the 3–4 min period post tracer injection. This study shows that esterification is the main pathway regulating free 11(12)-EpETrE levels in vivo.

Aculeatiols A-G: Lovastatin Derivatives Extracted from Aspergillus aculeatus.

In this study, we isolated lovastatin derivatives, including aculeatiols A-G (1-7) and three known compounds (8-10), from Aspergillus aculeatus. Their structures and absolute configurations were experimentally determined by high-resolution electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, and X-ray diffraction analyses, and the results were corroborated by quantum-chemical calculations. As members of the lovastatin derivatives, aculeatiols A-C (1-3) possess a γ-lactone functional group in the side chain. Compound 6 represents the first example that features an undescribed aromatized heterotetracyclic 6/6/6/6 ring system. Biologically, the lipid-lowering effects of all of these compounds were evaluated by analyzing the free fatty acid-induced intracellular lipid accumulation. In addition, compound 5, which regulated the transcription of genes associated with lipid uptake and synthesis, inhibited the accumulation of lipids.

Charge of a transmembrane peptide alters its interaction with lipid membranes

Transmembrane (TM) proteins interact closely with the surrounding membrane lipids. Lipids in the vicinity of TM proteins were reported to have hindered mobility, which has been associated with lipids being caught up in the rough surface of the TM domains. These reports, however, neglect one important factor that largely influences the membrane behavior — electrostatics of the TM peptides that are usually positively charged at their cytosolic end. Here, we study on the example of a neutral and a positively charged WALP peptide, how the charge of a TM peptide influences the membrane. We investigate both its dynamics and mechanics by: (i) time dependent fluorescent shift in combination with classical and FRET generalized polarization to evaluate the mobility of lipids at short and long-range distance from the peptide, (ii) atomic force microscopy to observe the mechanical stability of the peptide-containing membranes, and (iii) molecular dynamics simulations to analyze the peptide-lipid interactions. We show that both TM peptides lower lipid mobility in their closest surroundings. The peptides cause lateral heterogeneity in lipid mobility, which in turn prevents free lipid rearrangement and lowers the membrane ability to seal ruptures after mechanical indentations. Introduction of a positive charge to the peptide largely enhances these effects, affecting the whole membrane. We thus highlight that unspecific peptide-lipid interactions, especially the electrostatics, should not be overlooked as they have a great impact on the mechanics and dynamics of the whole membrane.

Identification of a monofunctional 3-deoxy-D-manno-octulosonic acid transferase of lipid A in Vibrio parahaemolyticus

Vibrio parahaemolyticus is associated with seafood, and its pathogenicity and antimicrobial resistance are closely related to lipid A. In V. parahaemolyticus, free lipid A species and complete lipopolysaccharide coexist but the reason is unknown. In Escherichia coli, this reaction to covert lipid A to the full-length lipopolysaccharide is catalyzed by a bifunctional 3-deoxy-d-manno-octulosonic acid (Kdo) transferase WaaA. In this study, a monofunctional Kdo transferase in V. parahaemolyticus encoded by VP_RS01035 was identified. When VP_RS01035 was deleted in V. parahaemolyticus ATCC33846, no full-length lipopolysaccharide was synthesized, but more free lipid A species were accumulated, and most of them were modified by phosphoethanolamine. When V. parahaemolyticus VP_RS01035 was overexpressed in a newly constructed E. coli waaA mutant WH001, and the full-length lipopolysaccharide was partially restored, suggesting that VP_RS01035 could replace waaA in E. coli. In addition, hexa-acylated lipid A and Kdo-lipid A species were directly extracted from WH001/pB2-RS01035, suggesting that V. parahaemolyticus VP_RS01035 is monofunctional and less efficient than E. coli WaaA. These results indicate that lipid A biosynthesis in V. parahaemolyticus can proceed without the addition of Kdo and V. parahaemolyticus VP_RS01035 plays an important role on lipid A diversity in V. parahaemolyticus.

Antioxidant Properties of Pistacia vera against the Effects of Phenylhydrazine-Induced Hemolytic Anemia on Male Fertility in Mice

Objective. The reproductive system can be adversely affected by anemia, characterized by elevated free radical production and lipid peroxidation. Conversely, the pistachio is well-known for its antioxidant capabilities. In this study, a mouse model was employed to investigate the safeguarding effects of the aqueous extract of pistachio (Pistacia vera) against oxidative stress induced by phenylhydrazine (PHZ)-triggered hemolytic anemia. Materials and methods. Forty-eight male mice were distributed into six distinct experimental groups (n = 8): control, PHZ, PHZ + 20Pis, PHZ + 80Pis, PHZ + 160Pis, and 80Pis groups. The experimental groups were administered a PHZ dose of 80 mg/kg/48 hr, along with pistachio doses of 20, 80, and 160 mg/kg/day, delivered intraperitoneally. After a period of 35 days, an assessment of sperm count, motility, morphology, and viability was conducted. Additionally, sperm chromatin quality was evaluated through Chromomycin A3, aniline blue, and toluidine blue staining. Hematoxylin–eosin staining was performed to examine the total diameter of seminiferous tubes and spermatogenic cells. Hormonal levels (FSH, LH, T) and antioxidant levels were analyzed using standard kits. Results. The PHZ groups exhibited a noteworthy decrease in various sperm parameters, as well as diminished chromatin quality assays and reduced levels of sex hormones when compared to the control group. Moreover, the morphometric evaluation indicated a substantial reduction in spermatogonia cell number, spermatid count, tubule count, seminiferous diameters, and seminiferous area in the PHZ group. Notably, the Pis group demonstrated the highest concentration of antioxidant contents. Conclusion. The protective impact of P. vera extract against PHZ-induced anemia on the male reproductive system in mice may be attributed to its abundant antioxidant components, which possess therapeutic properties at elevated levels.

Consumption of foods contaminated with heavy metals and their association with cardiovascular disease (CVD) using GAM software (cohort study)

IntroductionHeavy metals can enter the environment and food through industrial activities, acid rain, chemical fertilizers, pesticides, and sewage. A large amount of these metals is dangerous because they tend to bio accumulate. A concern with these metals is the long-term, low-dose exposure seen in the general population. HMs can cause disorders in the cardiovascular system through various mechanisms such as the production of free radicals, DNA damage, lipid peroxidation, and oxidative stress. Material and methodFood items measured in the present study included rice, bread, and vegetables. 210 participants (105 controls and 105 patients) were randomly selected for this study. The demographic information of the subjects was obtained from the Hoveyzeh Cohort Center. The relationship between heavy metals in food and cardiovascular diseases is investigated by The Generalized Additive Model (GAM). ResultThe results of the present study showed that when urine Cd was smoothed based on rice Cd, there was a significant correlation between urine Cd and Cd consumed in vegetables and rice. The GAM coefficient for urinary Cd excreted in case-control groups and Cd consumed in vegetables were 479.79(SE: 6.49–73.87) and 818.56(SE: 11.96–68.43), respectively, and for rice consumed, it was 0.03(SE: 0.015–2.103) and 0.04(SE: 0.017–2.338), respectively. The GAM coefficient for As consumption in vegetables and As in urine of case and control groups was 1.61 (SE: 9.48–0.16) and 22.36 (SE: 13.60–1.64), respectively. The same coefficient for rice consumption in case and control groups was 4.5 (SE: 0.62–7.22) and 10.48 (SE: 1.46–7.16), respectively. There was a very strong and significant correlation between the Sr in the urine of both groups and the Sr in the food consumed, so that the urinary Sr in the control group is excreted more than in the cardiovascular group. ConclusionGAM analysis indicates that As in vegetable and rice is more than the standard limitation value. Also, Sr and Cd in vegetables, rice, and bread were more than the standard limitation value. According to the GAM model As had a significant value in rice and vegetables indicating that As is more than the standard limitation value, therefore, it is associated with CVD.

Free Radical Lipid Peroxidation Induced by Reactive Halogen Species.

The review is devoted to the mechanisms of free radical lipid peroxidation (LPO) initiated by reactive halogen species (RHS) produced in mammals, including humans, by heme peroxidase enzymes, primarily myeloperoxidase (MPO). It has been shown that RHS can participate in LPO both in the initiation and branching steps of the LPO chain reactions. The initiation step of RHS-induced LPO mainly involves formation of free radicals in the reactions of RHS with nitrite and/or with amino groups of phosphatidylethanolamine or Lys. The branching step of the oxidative chain is the reaction of RHS with lipid hydroperoxides, in which peroxyl and alkoxyl radicals are formed. The role of RHS-induced LPO in the development of human inflammatory diseases (cardiovascular and neurodegenerative diseases, cancer, diabetes, rheumatoid arthritis) is discussed in detail.

Acetylated pelargonidin-3-O-glucoside alleviates hepatocyte lipid deposition through activating the AMPK-mediated lysosome-autophagy pathway and redox state.

Nonalcoholic fatty liver disease (NAFLD) is a worldwide public health issue, but a widely accepted therapy is still lacking until now. Anthocyanins are natural flavonoid compounds that possess various bioactivities, but their applications are limited due to their low bioavailability and stability. Acylated anthocyanins are reported to show higher stability, whereas their effects on NAFLD are still unclear. Herein, pelargonidin-3-O-(6''-acetyl)-glucoside (Ace Pg3G) was found to dose-dependently reduce intracellular lipid droplets and triglycerides, and improve cellular oxidative stress that accompanied lipid deposition. Besides, Ace Pg3G was proved to activate AMPK phosphorylation, thus stimulating AMPK-mediated lysosome-autophagy pathway to eliminate overloaded lipid. Further study unveiled that Ace Pg3G regulated genes related to lipid metabolism downstream of AMPK to inhibit lipid synthesis and accelerate lipid oxidation. Overall, this study provided the first evidence, to our best knowledge, that Ace Pg3G ameliorated free fatty acid-induced lipid deposition in hepatocytes through regulating AMPK-mediated autophagy pathways and redox state.

Development and Validation of Derivatization Method for Simultaneous Quantitation of Asteracantha longifolia (L.) Nees Phytoconstituents by Liquid Chromatography–Electrospray Ionization–Mass Spectrometry/Mass Spectrometry

ABSTRACT Background: Betulin, lupeol, stigmasterol, and β-sitosterol are the active phytoconstituents accountable for the practical application of Asteracantha longifolia (L.) Nees in ayurvedic treatments as antitumor, hypoglycemic, aphrodisiac, antibacterial, free radical scavenging, lipid peroxidation, and hepatoprotective agent. As an essential medicinal plant in modern and traditional medicine, regularly checking raw material’s quality attributes and quantifying the phytoconstituents is indispensable. Aim: The aim of this study was to optimize derivatization conditions of these four essential phytoconstituents with p-toluenesulfonyl isocyanate (PTSI) reagent and the development of a liquid chromatography–electrospray ionization (ESI)–mass spectrometry (MS)/MS method that aids in the simultaneous detection of these four phytoconstituents. Objective: Thus, derivatization enhances sensitivity for detection in the negative mode with an electron spray ionization source and tandem mass spectroscopy. Further, the sensitive and rapid analytical method for simultaneous quantitation of betulin, lupeol, stigmasterol, and β-sitosterol is subsequently validated in line with the guidelines by ICH and used to quantify the phytoconstituents in two over-the-counter herbal formulations and one plant extract isolated at laboratory scale under batch analysis. Materials and Methods: PTSI reagent of purity <98% procured from TCI and other chromatography reagents of MS grade were utilized in the optimization of an analytical method. Results: The developed LC-ESI-MS/MS-based method demonstrated specificity for the targeted phytoconstituents, with LOD and LOQ values of < 0.13 ng/mL and 0.4 ng/mL, respectively. Linearity was established with a correlation coefficient ≥ 0.998 over a concentration range of 0.2 ng/mL to 6 ng/mL. Precision, expressed as %RSD for peak response, was ≤ 5%. The method showed satisfactory recovery for betulin (98.5%-108.3%), lupeol (95.0%-109.3%), stigmasterol (101.9%-117.0%), and β-sitosterol (99.1%-116.2%). Conclusion: The reagent PTSI reacts rapidly and forms stable derivatives. The derivatization of active phytoconstituents betulin, lupeol, stigmasterol, and β-sitosterol has enhanced the detection sensitivity of the analytical method.

Carnitine in Alleviation of Complications Caused by Acute Valproic Acid Toxicity; an Exprimental Study on Mice.

Hyperammonemia and hepatotoxicity are well-known complications of valproic acid (VPA) poisoning. The objective of this study is to evaluate the potential role of carnitine in mitigating the adverse effects of acute VPA toxicity in mice. 54 male mice (25-30 g) were randomly assigned to one of three categories, including acute, sub-acute, and chronic poisoning. Each category contained 3 groups, each consisting of 6 mice (Group 1: control, Group 2: VPA treated, and Group 3: VPA + carnitine treated). The animals were sacrificed 24 hours after the initial injection, and their blood, liver, and brain samples were compared between groups of each category regarding liver function biomarkers, oxidative stress markers, ammonia level, and liver histopathologic changes using one-way ANOVA followed by Tukey's multiple comparison test. The administration of VPA increased the serum level of aspartate aminotransferase (AST) (p=0.003) and alanine aminotransferase (ALT) (p=0.001), as well as serum, and brain level of ammonia (p=0.0001 for both) in the intervention group. Elevated levels of lipid peroxidation and oxidative stress (p=0.0001 for both) in the liver tissue, decreased liver glutathione (p=0.0001) and ferric ion-reducing antioxidant power (FRAP) (p=0.0001), and histopathologic changes in the form of moderate to severe inflammation were observed. Administration of VPA + carnitine reduced AST (p=0.05) and ALT (p=0.01), increased the FRAP, reduced free oxygen radicals and liver lipid peroxidation (p=0.0001 for all), and decreased tissue damage in the form of moderate inflammation. The administration of carnitine was ineffective in reducing brain or plasma ammonia levels in acute VPA-treated animals (p = 0.0115). Although the administration of carnitine has been suggested as a protective remedy in cases of VPA toxicity, according to the present study, it did not have an antidotal effect and did not prevent encephalopathy or liver injury in acute VPA toxicity.