Overproduction Of Nitric Oxide Research Articles

Discovery of pyrazolo[1,5-a]pyrimidine derivatives targeting TLR4−TLR4∗ homodimerization via AI-powered next-generation screening

TLR4 signaling is instrumental in orchestrating multiple aspects of innate immunity. Developing small molecule inhibitors targeting the TLR4 pathway holds potential therapeutic promise for TLR4-related disorders. Herein, an artificial intelligence (AI)-powered next-generation screening approach, employing HelixVS and HelixDock, was utilized to focus on the TLR4−TLR4∗ (a second copy of TLR4) homodimerization surface, leading to the identification of a potent pyrazolo[1,5-a]pyrimidine derivative, designated as compound 1. An extensive structure−activity relationship (SAR) exploration culminated in the discovery of the lead compound TH023, which effectively blocked the LPS-stimulated NF-κB activation and nitric oxide overproduction in HEK-Blue hTLR4 and RAW264.7 cells, with IC50 values of 0.354 and 1.61 μM, respectively. Molecular dynamic (MD) simulations indicated that TH023 stabilized TLR4−MD-2 and disrupted its association with TLR4∗. Moreover, TH023 alleviated the lung injury and decreased pro-inflammatory cytokine levels in LPS-induced septic mice. These findings not only illuminated the strategic advantage of HelixDock in advancing the frontiers of AI-driven drug discovery, but also provided valuable structural insights for the rational design of TLR4−TLR4∗ protein−protein interaction (PPI) inhibitors based on the pyrazolo[1,5-a]pyrimidine scaffold. Overall, this study validated a new strategy for TLR4 signaling regulation by targeting its dimerization, thereby underscoring the therapeutic promise of TH023 in treating TLR4-mediated inflammatory diseases.

Comparison of the anti-inflammatory effects of carotenoids-rich product from microalgal mass-cultured between natural seawater and magma seawater

Microalgae can be mass-produced in a short period of time and are rich in high value-added product such as carotenoids, thereby it is widely used in a variety industrial field. However, the production cost expensed a lot due to high price of culture ingredient, vitamins. Additionally, > 80% of synthetic carotenoids are used in industrial field, and their cost is also highly expensed. Therefore, in this study, a microalga, Tetraselmis sp. was mass-cultured using natural seawater (NS) and magma seawater (MS) as vitamins. As a result of comparing the general composition between the extracts cultured in two culture media, crude carbohydrate and crude lipid contents were 2.68% and 4.38% higher, respectively, while crude protein content was 4.1% lower in the MS culture media. The extraction yield was 8.6% higher in the MS than the NS culture media. Also, lutein and zeaxanthin were predominantly presented in the species and detected in the microalgal extract cultured in MS was 2- and 8-folds higher, respectively, than in NS. Consequently, the carotenoids-rich extracts cultured with two seawaters were exhibited prominent anti-inflammatory effects by suppressing nitric oxide (NO) overproduction and pro-inflammatory mediator such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 expression through MAPKSs and NF-κB pathway. Interestingly, extract of microalgal cultured in MS showed a more efficient anti-inflammatory effect. These results suggest that the value of MS in increasing the carotenoids contents with beneficial effects in mass cultivation of microalgae.

Triphenyltin(IV) compounds bearing modulated azo-carboxylato ligands: Synthesis, structural characterization, in vitro cytotoxicity, BSA/DNA binding affinity, and in silico studies

Three novel triphenyltin(IV) compounds with modulated azo-carboxylato ligands: triphenylstannyl (E)-4-((2-hydroxynaphthalen-1-yl)diazenyl)benzoate, 1, triphenylstannyl (E)-4-((4-hydroxyphenyl)diazenyl)benzoate, 2, and triphenylstannyl (E)-4-((4-(dimethylamino)phenyl)diazenyl)benzoate, 3, were synthesized and characterized by elemental analysis, FTIR and NMR (1H, 13C, 119Sn) spectroscopy. The structures and spectra of compounds were predicted by Density Functional Theory (DFT) methods at B3LYP-D3BJ/6–311++G(d,p)(H,C,N,O)/LanL2DZ(Sn) level of theory. Furthermore, the antitumor potential of ligand precursors, HL1–HL3, and appropriate organotin(IV) compounds 1–3 was evaluated across mouse melanoma B16F1, human breast adenocarcinoma MCF-7, human colorectal HT-29 and human prostate PC3 cell lines using MTT and CV assays. The organotin(IV) compounds exhibit enhanced cellular uptake and efficacy in reducing viable cell numbers when compared to free acids. Specifically, compound 3 demonstrates a notable impact at lower nanomolar concentrations on all tested cell lines. Moreover, 3 induces cell death in MCF-7 cells by inhibiting cell division and promoting the overproduction of cellular nitric oxide (NO), ultimately leading to caspase-independent apoptosis. Importantly, this process occurs without concurrent activation of autophagy or the generation of ROS/RNS species. The binding affinity of 1–3 with calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy and molecular docking simulations, suggesting their capacity to interact with these biomolecules.

Uncovering Novel Protein Partners of Inducible Nitric Oxide Synthase in Human Testis.

Peroxidative damage to human spermatozoa has been shown to be the primary cause of male infertility. The possible role of nitric oxide (NO) in affecting sperm motility, capacitation, and acrosome reaction has been reported, too. The overproduction of NO by the enzyme inducible nitric oxide synthase (iNOS) could be responsible as it has been implicated in the pathogenesis of many diseases. There have been many studies on regulating iNOS function in various tissues, especially by protein-protein interaction; however, no study has looked for iNOS-interacting proteins in the human testis. Here, we have reported the identification of two proteins that interact with iNOS. We initially undertook a popular yeast two-hybrid assay to screen a human testis cDNA library in yeast using an iNOS-peptide fragment (amino acids 181-335) as bait. We verified our data using the mammalian chemiluminescent co-IP method; first, employing the same peptide and, then, a full-length protein co-expressed in HEK293 cells in addition to the candidate protein. In both cases, these two protein partners of iNOS were revealed: (a) sperm acrosome-associated 7 protein and (b) retinoblastoma tumor-suppressor binding protein.

Retrospectively gated ultrashort-echo-time MRI T1 mapping reveals compromised pulmonary microvascular NO-dependent function in a murine model of acute lung injury.

This study sought to develop noninvasive, in vivo imaging schemes that allow for quantitative assessment of pulmonary microvascular functional status based on the combination of pulmonary T1 mapping and dynamic contrast-enhanced (DynCE) imaging. Ultrashort-echo-time (UTE) imaging at 9.4 T of lung parenchyma was performed. Retrospective gating was based on modulation of the first point in each recorded spoke. T1 maps were obtained using a series of five consecutive images with varying RF angles and analyzed with the variable flip angle approach. The obtained mean T1 lung value of 1078 ± 38 ms correlated well with previous reports. Improved intersession variability was observed, as evident from a decreased standard deviation of motion-resolved T1 mapping (F-test = 0.051). Animals received lipopolysaccharide (LPS) and were imaged at t= 2, 6, and 12 h after administration. The nitric oxide (NO)-dependent function was assessed according to changes in lung T1 after L-NAME injection, while microvascular perfusion and oxidant stress were assessed with contrast-enhanced imaging after injection of gadolinium or 3-carbamoyl-proxyl nitroxide radical, respectively. Retrospectivel gated UTE allowed robust, motion-compensated imaging that could be used for T1 mapping of lung parenchyma. Changes in lung T1 after L-NAME injection indicated that LPS induced overproduction of NO at t= 2 and 6 h after LPS, but NO-dependent microvascular function was impaired at t= 12 h after LPS. DynCE imaging at t= 6 h after LPS injection revealed decreased microvascular perfusion, with increased vascular permeability and oxidant stress. MRI allows to visualize and quantify lung microvascular NO-dependent function and its concomitant impairment during acute respiratory distress syndrome development with high sensitivity. UTE T1 mapping appears to be sensitive and useful in probing pulmonary microvascular functional status.

Modification-Specific Proteomic Analysis Reveals Cysteine S-Nitrosylation Mediated the Effect of Preslaughter Transport Stress on Pork Quality Development.

This study aimed to explore the effects of preslaughter transport stress on protein S-nitrosylation levels and S-nitrosylated proteome in post-mortem pork longissimus thoracis (LT) muscle. Pigs (N= 16) were randomly divided into 3 h transport (high-stress group, HS) and 3 h transport followed by 3 h resting treatments (low-stress control group, LS). Results demonstrated that high transport stress levels induced nitric oxide (NO) overproduction by promoting NO synthase (NOS) activity and neuronal NOS (nNOS) expression, which thereby notably increased protein S-nitrosylation levels in post-mortem muscle (p < 0.05). Proteomic analysis indicated that 133 S-nitrosylation-modified cysteines belonging to 85 proteins were significantly differential, of which 101 cysteines of 63 proteins were higher in the HS group (p < 0.05). Differential proteins including cytoskeletal and calcium-handling proteins, glycolytic enzymes, and oxidoreductase were mainly involved in the regulation of muscle contraction and energy metabolism that might together mediate meat quality development. Overall, this study provided direct evidence for changes in S-nitrosylation levels and proteome in post-mortem muscle in response to preslaughter transport stress and revealed the potential impact of S-nitrosylated proteins on meat quality.

QSAR Studies of Nitric Oxide Synthase Inhibitors

Background:: Nitric oxide is a free radical bioregulator controlling homeostasis, vasodilation, and inhibition of platelet aggregation, significantly implicated in the nervous and immune system functionality. In vivo it is produced by nitric oxide synthases (NOSs). Objective:: Overproduction of nitric oxide is linked to several inflammatory, immunological, and neurodegenerative diseases and for that, various compounds have been synthesized as inhibitors of NOSs. In this review, the QSAR analyses were summarized in a variety of compounds as potent inhibitors of NOSs, and the models derived through 1D, 2D and 3D QSAR analyses. Conclusion:: Ten groups of various NOS inhibitors and 17 1D, 2D, and 3D QSAR models and analyses were presented and discussed. A lack of hydrophobic terms was noticed in most of the cases. Chemical substituents were selected considering the increase either of the hydrophilicity and/or of hydrophobicity, bulkiness supported steric interactions, and point to potent inhibitors. CMR (Calculated Molar Refractivity) a steric variable, with a negative sign, underlines the critical effects participating on (in) an active site on the enzymes. Indicator variables imply the influence of specific structural moieties. Electronic parameters were found to be significant.

Variation in Exon 29 of the NOS1 Gene Does Not Contribute to Parkinson's Disease in the North Karnataka Population.

Nitric oxide (NO) overproduction has been found to have neurotoxic effects on the brain. Moreover, in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced, the suppression of the NO-synthesizing enzymes, such as neuronal nitric oxide synthase (nNOS) and inducible NOS (iNOS), has neuroprotective benefits in Parkinson's disease (PD). These findings imply that NOS may have a role in regulating the nigral dopaminergic neurons' tolerance to environmental stressors in PD. In the present study, we investigated variations in the NOS1 gene that may raise the likelihood of PD. PD patients who visited the neurology departments of several medical colleges and hospitals in North Karnataka, India, between 2009 and 2011 were included in the study. The detailed clinic pathological details were obtained from 100 PD patients. Genomic DNA was isolated using the kit method followed by the evaluation of the quality and quantity of isolated gDNA. Polymerase chain reaction (PCR) amplification of exon 29 was performed, and sequencing was performed using the Applied BiosystemsABI 3500 Sanger sequencing platform. The present study is comprised of 100 PD patients, which includes 65 males and 35 females. There were 64 sporadic, 34 idiopathic, and two familial PD cases. The majority (67.1%) of PD cases were from metropolitan areas. Community-based segregation showed that the maximum cases were from Hindu Lingayat. A proportion (90.8%) of the patients had tremors, 32.7% of them displayed slowness in their daily tasks, and 8.1% of them had dyskinesia. Molecular analysis showed two untranslated region(UTR) variations g.151787 del T (rs1434015950) and g.151745 C>T (rs2682826) in our study group. The absence of mutations in the targeted NOS1 gene in the PD patients from North Karnataka shows the involvement of other genes in the molecular pathophysiology. Thus, it is crucial to screen other possible genes using cutting-edge technology to obtain a clear picture of the genetics of PD.

Two pyrrole acids isolated from Phyllanthus emblica L. and their bioactivities

An undescribed pyrrole acid, 1-(4′-methoxy-4′-oxobutyl)-1 H-pyrrole-2,5-dicarboxylic acid (1) and one known pyrrole acid (2) were isolated from the fruits of Phyllanthus emblica. The structures of these compounds were elucidated via the comprehensive analyses of IR, HRESIMS, 1D and 2D spectroscopic data. A series of biological assays revealed that compounds 1 and 2 could inhibit LPS-induced over-production of nitric oxide (NO), interleukin-6 (IL-6), monocyte chemotactic protein 1 (MCP-1) and tumor necrosis factor-α (TNF-α) by reducing the phosphorylation of extracellular regulated protein kinases (ERK) and c-Jun N-terminal kinases (JNK) in RAW 264.7 cells. Additionally, compounds 1 and 2 were found to reduce lipid deposition and increase the mRNA expression of ATP-binding cassette transporter A1 in oxidized low-density lipoprotein-treated RAW264.7 macrophages.Graphical abstract

Edaravone Improves Streptozotocin-Induced Memory Impairment via Alleviation of Behavioral Dysfunction, Oxidative Stress, Inflammation, and Histopathological Parameters.

Alzheimer's disease (AD), as the main cause of dementia, has a progressive and neurodegenerative pattern with number of cases increasing over the next decades. Therefore, discovering an effective treatment with the ability to invert memory impairment and pathophysiological events of AD seems to be required. The present study performed to investigate the probable effects of Edaravone (EDV) in AD-like disorder induced by intracerebroventricular streptozotocin (ICV-STZ) administration in mice. This study also compares the two different methods of ICV-STZ in the memory impairment induction. NMRI male mice were administrated with 3 mg/kg of STZ for two times during 48 hours span, and after 24 hours, animals were treated with EDV (5 and 10 mg/kg), Donepezil, and Memantine for 14 days. After behavioral tests regarding memory and cognitive function, animals were sacrificed, and the hippocampi were utilized for further analyses. Our results demonstrated that administration of STZ induced memory impairment in the Morris water maze (MWM) test and decreased the discriminative factor in novel object recognition (NOR). The biochemical output shows a significant decrease in ferric reducing antioxidant power (FRAP) and glutathione (GSH) levels followed by increase in malondialdehyde (MDA) and protein carbonylation (PCO) levels. The output showed no difference between the patterns of AD-like disorder induction. Following our treatment groups, administration of EDV (5 and 10 mg/kg), Donepezil, and Memantine significantly improved memory performance and discriminatory behavior. Aforementioned treatments managed to improve FRAP and GSH content of hippocampus, while significantly attenuating MDA, PCO, and nitric oxide overproduction. In addition, no significant difference has been observed between the effect of 5 and 10 mg/kg EDV application. It was supposed that EDV managed to ameliorate memory dysfunction, discriminatory behavior, oxidative stress, and cellular antioxidant power in a dose-independent pattern in mice.

Values of Nitric Oxide and Superoxide Dismutase in Cerebrospinal Fluid of Patients with Sporadic Amyotrophic Lateral Sclerosis.

Neurons are highly energy-dependent and highly specialized cells, showing great sensitivity to oxidative stress (OS). Nitric oxide (NO) and its oxidation products play a central role in neurodegeneration. This study aimed to contribute to the further elucidation of the role of OS in the pathogenesis of amyotrophic lateral sclerosis (ALS). We assessed NO and superoxide dismutase (SOD) levels in cerebrospinal fluid (CSF) of 24 sporadic ALS (sALS) patients (13 of them presented with spinal form while 11 patients had bulbar form) and 20 controls (CG). The obtained SOD levels in sALS patients were lower than those in CG (p < 0.001), while NO showed higher levels compared to CG (p < 0.001). Observed separately, there were no significant differences in the levels of NO and SOD in CSF between patients about their clinical presentations (p > 0.05). There were significant negative correlations between SOD and NO levels in all sALS patients (r = 0.31, P = 0.025). Significant correlation between SOD and functional rating scale as well as disease progression index was recorded in patients with sALS (r = 0.618. r = 0.425, P < 0.01), while NO levels were significantly associated with disease progression only (r = 0.348, P < 0.01). The data presented clearly support the role of impaired oxidant/antioxidant balance in the pathogenesis of ALS, where NO overproduction and decreased SOD defense activity seem to be particularly involved. The CSF SOD and NO level might serve as useful biomarkers for functional disorder and progression of the disease.

Nitric Oxide Synthases in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by severe joint damage and disability. However, the specific mechanism of RA has not been thoroughly clarified over the past decade. Nitric oxide (NO), a kind of gas messenger molecule with many molecular targets, is demonstrated to have significant roles in histopathology and homeostasis. Three nitric oxide synthases (NOS) are related to producing NO and regulating the generation of NO. Based on the latest studies, NOS/NO signaling pathways play a key role in the pathogenesis of RA. Overproduction of NO can induce the generation and release of inflammatory cytokines and act as free radical gas to accumulate and trigger oxidative stress, which can involve in the pathogenesis of RA. Therefore, targeting NOS and its upstream and downstream signaling pathways may be an effective approach to managing RA. This review clearly summarizes the NOS/NO signaling pathway, the pathological changes of RA, the involvement of NOS/NO in RA pathogenesis and the conventional and novel drugs based on NOS/NO signaling pathways that are still in clinical trials and have good therapeutic potential in recent years, with an aim to provide a theoretical basis for further exploration of the role of NOS/NO in the pathogenesis, prevention and treatment of RA.

Network pharmacology-based identification of bioavailable anti-inflammatory agents from Psoralea corylifolia L. in an experimental colitis model

Ethnopharmacological relevanceIn traditional oriental medicine, the dried seeds of Psoralea corylifolia L. (PC) have been used to treat various diseases, including gastrointestinal, urinary, orthopedic, diarrheal, ulcer, and inflammatory disorders. Aim of the studyAlthough its various biological properties are well-known, there is no information on the therapeutic effects and bioavailable components of PC against inflammatory bowel disease. Therefore, we focused on the relationship between hydroethanolic extract of PC (EPC) that ameliorates colitis in mice and bioactive constituents of EPC that suppress pro-inflammatory cytokines in macrophages. Materials and methodsWe investigated the therapeutic effects of EPC in a dextran sulfate sodium-induced colitis mouse model and identified the orally absorbed components of EPC using UPLC-MS/MS analysis. In addition, we evaluated and validated the mechanism of action of the bioavailable constituents of EPC using network pharmacology analysis. The effects on nitric oxide (NO) and inflammatory cytokines were measured by Griess reagent and enzyme linked immunosorbent assay in lipopolysaccharide (LPS)-induced macrophages. ResultsIn experimental colitis, EPC improved body weight loss, colon length shortening, and disease activity index. Moreover, EPC reduced the serum levels of pro-inflammatory cytokines and histopathological damage to the colon. Network pharmacological analysis identified 13 phytochemicals that were bioavailable following oral administration of EPC, as well as their potential anti-inflammatory effects. 11 identified EPC constituents markedly reduced the overproduction of NO, tumor necrosis factor-α, and/or interleukin-6 in macrophages induced by LPS. The LPS-induced expression of the nuclear factor kappa-light-chain-enhancer of activated B cells reporter gene was reduced by the 4 EPC constituents. ConclusionsThe results indicate that the protective activity of EPC against colitis is a result of the additive effects of each constituent on the expression of inflammatory cytokines. Therefore, it suggests that 11 bioavailable phytochemicals of EPC could aid in the management of intestinal inflammation, and also provides useful insights into the clinical application of PC for the treatment of inflammatory bowel diseases.

Aging-associated increased nitric oxide production is a potential cause of inferior eggshell quality produced by aged laying hens

It is important to prolong the productive life of laying hens without compromising their welfare. Therefore, in this study, we aimed to identify the cause for inferior quality egg production of aged hens by investigating the aging-associated molecular changes related to eggshell formation in the isthmic and uterine mucosae and determining whether nitric oxide plays a role in decreasing the quality of eggs produced by aged hens. Young (35 weeks old) and aged (130 weeks old) White Leghorn laying hens were used in this study to determine the effects of age on the expression of proteins related to eggshell membranes formation in the isthmus and eggshell biomineralization and nitric oxide production in the uterus. Nitric oxide synthesis during the ovulatory cycle was examined in twenty-five laying hens (46–52 weeks old) euthanized at 0, 4, 7, 16, and 24 h after oviposition. S-Nitroso-N-acetylpenicillamine (a nitric oxide donor) was added to the cultured isthmic and uterine mucosal cells to examine the effects of nitric oxide on the expression of genes related to eggshell membranes formation and eggshell biomineralization, respectively. The results showed that the protein abundance of collagen I and V in the isthmic mucosa and collagen V in the eggshell membranes were lower in aged hens than in young hens. The mRNA expression levels of calbindin, osteopontin, and ovocalyxin-36 and the protein abundance of calbindin and carbonic anhydrase-2 were lower in the uterine mucosa of aged hens than in that of young hens. Nitric oxide synthesis was higher in the uterine mucosa of aged hens than in that of young hens. Nitric oxide downregulated the mRNA expression levels of osteopontin and ovocalyxin-36 in cultured uterine mucosal cells. Our results indicated that the eggshell quality decreases with aging due to molecular changes in the uterine mucosa affecting the eggshell membrane formation and eggshell biomineralization. Moreover, nitric oxide overproduction may play a role in this dysfunction.

Combination Sodium Nitrite and Hydralazine Therapy Attenuates Heart Failure With Preserved Ejection Fraction Severity in a "2-Hit" Murine Model.

Background Recent studies have suggested that cardiac nitrosative stress mediated by pathological overproduction of nitric oxide (NO) via inducible NO synthase (iNOS) contributes to the pathogenesis of heart failure with preserved ejection fraction (HFpEF). Other studies have suggested that endothelial NO synthase (eNOS) dysfunction and attenuated NO bioavailability contribute to HFpEF morbidity and mortality. We sought to further investigate dysregulated NO signaling and to examine the effects of a NO-based dual therapy (sodium nitrite+hydralazine) following the onset of HFpEF using a "2-hit" murine model. Methods and Results Nine-week-old male C57BL/6 N mice (n=15 per group) were treated concurrently with high-fat diet and N(ω)-nitro-L-arginine methyl ester (L-NAME)(0.5 g/L per day) via drinking water for 10 weeks. At week 5, mice were randomized into either vehicle (normal saline) or combination treatment with sodium nitrite (75 mg/L in the drinking water) and hydralazine (2.0 mg/kg IP, BID). Cardiac structure and function were monitored with echocardiography and invasive hemodynamic measurements. Cardiac mitochondrial respiration, aortic vascular function, and exercise performance were also evaluated. Circulating and myocardial nitrite were measured to determine the bioavailability of NO. Circulating markers of oxidative or nitrosative stress as well as systemic inflammation were also determined. Severe HFpEF was evident by significantly elevated E/E', LVEDP, and Tau in mice treated with L-NAME and HFD, which was associated with impaired NO bioavailability, mitochondrial respiration, aortic vascular function, and exercise capacity. Treatment with sodium nitrite and hydralazine restored NO bioavailability, reduced oxidative and nitrosative stress, preserved endothelial function and mitochondrial respiration, limited the fibrotic response, and improved exercise capacity, ultimately attenuating the severity of "two-hit" HFpEF. Conclusions Our data demonstrate that nitrite, a well-established biomarker of NO bioavailability and a physiological source of NO, is significantly reduced in the heart and circulation in the "2-hit" mouse HFpEF model. Furthermore, sodium nitrite+hydralazine combined therapy significantly attenuated the severity of HFpEF in the "2-hit" cardiometabolic HFpEF. These data suggest that supplementing NO-based therapeutics with a potent antioxidant and vasodilator agent may result in synergistic benefits for the treatment of HFpEF.

Identification and Molecular Mechanism of Novel Immunomodulatory Peptides from Gelatin Hydrolysates: Molecular Docking, Dynamic Simulation, and Cell Experiments.

The purpose of this study was to identify donkey-hide gelatin-derived immunomodulatory peptides targeting Toll-like receptor 4-myeloid differentiation 2 (TLR4-MD2) and elucidate their binding modes using physicochemical property prediction, molecular docking, molecular dynamics simulations, and in vitro cell experiments. After hydrolyzing gelatin, 519 peptides were identified by liquid chromatography-tandem mass spectrometry. Peptides VQLSGEEK and GFSGLDGAKG bound to TLR4-MD2 with high binding affinity. In TLR4-MD2, Arg90, Ser118, Phe126, Tyr131, and Arg264 were key residues involved in the binding of these peptides. The RMSD and Rg values demonstrated that VQLSGEEK-TLR4-MD2 and GFSGLDGAKG-TLR4-MD2 complexes had stable and compact conformations. VQLSGEEK and GFSGLDGAKG were found to increase the cell viability and phagocytic activity of RAW264.7 macrophages; significantly promote the production of cytokines TNF-α, IL-1β, and IL-6 in cells; and inhibit the overproduction of nitric oxide (NO) and cytokines in lipopolysaccharide (LPS)-induced RAW264.7 cells. Our results provided preliminary evidence that VQLSGEEK and GFSGLDGAKG could function as two-way immunomodulatory peptides with immunostimulatory and anti-inflammatory activities.

A comparative study of fermented buffalo and camel milk with anti-inflammatory, ACE-inhibitory and anti-diabetic properties and release of bio active peptides with molecular interactions: In vitro, in silico and molecular study

The aim of this study is to compare ACE inhibitory, anti-diabetic and Anti-inflammatory activity of buffalo and camel milk using Lacticaseibacillus paracasei (M11) in combination with yeast Saccharomyces cerevisiae (WBS2A) and to release peptides with antihypertensive and anti-diabetic properties. Fermented buffalo and camel milk were considered for the evaluation of Angiotensin-converting enzyme (ACE) inhibitory and anti-diabetic activities at specific time intervals (12, 24, 36 and 48 h) at 37 °C. For the growth condition optimization, proteolytic activity was evaluated with specific inoculation rates (1.5%, 2.0%, and 2.5%) and at specific incubation periods (12, 24, 36, and 48 h). The highest peptides were produced at 2.5% inoculation rate and at 48 h of incubation in both buffalo and camel milk at 37 °C. Further, camel and buffalo milk fermented with M11+WBS2A significantly lower the overproduction of TNF-α, IL-6, IL-1β and Nitric oxide (NO), that was induced by lipopolysaccharide (LPS) stimulation in RAW 267.4 cells. For protein purification, 2D gel electrophoresis and SDS-PAGE were used. Camel and buffalo milk that had not been fermented displayed protein bands between 10 and 100 kDa and 10 and 75 kDa respectively, whereas all the fermented samples showed bands between 10 and 75 kDa. On SDS-PAGE, in permeates, there were no apparent protein bands. When fermented buffalo and camel milk were electrophoresed in 2D gel, a total of 26 and 25 protein spots were found. In 2D gel electrophoresis, protein spots had sizes between 10 and 37 kDa. In RP-HPLC, water-soluble extracts (WSEs) of ultra-filtered fractions were used to distinguish different fractions of a peptide. Peakview software was used to characterize the LC/MS results. Fourier transform-infrared spectroscopy (FTIR) was used to evaluate various functional groups of fermented milks. In molecular docking study, the peptide sequences identified from the fermented buffalo milk (FBM) and camel milk (FCM) were examined for their binding affinity against the binding sites of hPAM and hMGA.

Does the Prolonged Duration of Continuous Ambulatory Peritoneal Dialysis Affect the Serum Levels of Endothelin-1 and Nitric Oxide?

End-stage renal disease and its treatment with continuous ambulatory peritoneal dialysis (CAPD) can affect almost all organs and organ systems including vascular endothelium. Consequently, disturbance in the production of vasoactive substances endothelin-1 (ET-1) and nitric oxide (NO) occurs in these patients. There are only a small number of studies that investigated the impact of long-term CAPD on imbalance in production of vasoactive substances ET-1 and NO among these patients. Therefore, our study aimed to investigate the impact of duration of CAPD on potential overproduction of ET-1 and NO in uremic patients. This study included 23 uremic patients [10 males, mean age: 56.3 (±16.2) years] treated with CAPD. All studied patients were further divided into subgroups, groups A and B. Group A included patients on treatment with CAPD <5 years, and group B included those on treatment longer than five years. Our results showed that serum levels of these vasoactive substances are significantly higher among patients treated with CAPD longer than five years (ET-1: 51.24 ± 32.11 vs. 139.53 ± 42.42; NO: 15.50 ± 2.57 vs. 26.57 ± 5.96, respectively). We concluded that imbalance in production of vasoactive substances is present in long-term CAPD treatment and this imbalance can lead to disturbance in the local blood flow control.

NO-induced apoptosis in human melanocytes from lightly and darkly pigmented skin.

Nitric oxide (NO) is a potent modulator of programmed cell death, with the ability to both induce and prevent apoptosis. Some of the factors that are capable of triggering apoptosis of skin cells also cause NO overproduction in the epidermis. Unlike keratinocytes, melanin-producing melanocytes are highly resistant to apoptotic death. To investigate whether NO can induce apoptosis in normal human epidermal melanocytes and whether the pigmentation phenotype of the cells can affect their response to NO. Human epidermal melanocytes, derived from lightly and darkly pigmented neonatal foreskins, were cultured in the presence of various concentrations of SPER/NO. The effect of NO released from its donor on the cell morphology, viability, and proliferation was assessed. The ability of NO to induce cell apoptosis was evaluated by Hoechst 33342 staining, DNA fragmentation assay, flow cytometry with annexin V and propidium iodide staining, determination of caspase 3/7, 8, and 9 activities, and assessment of changes in the cell expression levels of BAX and BCL-2. We have shown that NO is capable of inducing apoptosis in normal human epidermal melanocytes in vitro, with preferential activation of the intrinsic (mitochondrial) pathway. Melanocytes from darkly pigmented skin showed a strong increase in BCL-2 expression in response to NO and were significantly more resistant to apoptosis than those from lightly pigmented skin. The pigmentation phenotype may be an important factor modulating the response of human epidermal melanocytes to proapoptotic activity of extracellular NO.

Berberine hydrochloride inhibits migration ability via increasing inducible NO synthase and peroxynitrite in HTR-8/SVneo cells

Ethnopharmacological relevanceInadequate trophoblasts migration and invasion is considered as an initial event resulting in preeclampsia, which is closely related to oxidative stress. Berberine hydrochloride (BBR), extracted from the traditional medicinal plant Coptis chinensis Franch., exerts a diversity of pharmacological effects, and the crude drug has been widely taken by most Chinese women to treat nausea and vomit during pregnancy. But there is no research regarding its effects on trophoblast cell function. Aim of the studyThis study aimed to investigate the effect of BBR on human-trophoblast-derived cell line (HTR-8/SVneo) migration ability and its mechanism. Materials and methodsCell viability was detected by CCK-8 assay. The effect of BBR on cells migration function was examined by scratch wound healing assay and transwell migration assay. Intracellular nitric oxide (NO), superoxide (O2−) and peroxynitrite (ONOO−) levels were measured by flow cytometry. The expression levels of inducible NO synthase (iNOS), eNOS, p-eNOS, MnSOD, CuZnSOD, Rac1, NOX1, TLR4, nuclear factor-κB (NF-κB), p-NFκB, pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) in cells were analyzed by Western blotting. Uric acid sodium salt (UA), the scavenger of ONOO−, PEG-SOD (a specific superoxide scavenger), L-NAME (a NOS inhibitor) and antioxidants (Vit E and DFO) were further used to characterize the pathway of BBR action. Results5 μM BBR decreased both the migration distance and the number of migrated cells without affecting cells viability in HTR-8/SVneo cells after 24 h treatment. BBR could increase the level of NO in HTR-8/SVneo cells, and the over-production of NO might be attributable to iNOS, but not eNOS. BBR could increase intracellular O2− levels, and the over-production of O2− is closely related with Rac1 in HTR-8/SVneo cells. The excessive production of NO and O2− further react to form ONOO−, and the increased ONOO− level induced by BBR was blunted by UA. Moreover, UA improved the impaired migration function caused by BBR in HTR-8/SVneo cells. The depressed migration function stimulated by BBR in HTR-8/SVneo cells was diminished by PEG-SOD and L-NAME. Furthermore, BBR increased the expression of IL-6 in HTR-8/SVneo cells, and antioxidants (Vit E and DFO) could decrease the expression of IL-6 and iNOS induced by BBR. ConclusionsBBR inhibits the cell migration ability through increasing inducible NO synthase and peroxynitrite in HTR-8/SVneo cells, indicating that BBR and traditional Chinese medicines containing a high proportion of BBR should be used with caution in pregnant women.