Preventive effects of Salvia officinalis leaf extract on insulin resistance and inflammation in a model of high fat diet-induced obesity in mice that responds to rosiglitazone

Preventive effects of salvia officinalis leaf extract on insulin resistance and inflammation, in high fat diet-induced-obesity mice model

10.7287/peerj.preprints.3086v1 ◽

2017 ◽

Author(s):

Mohamed Raafet Ben Khedher ◽

Mohamed Hammami ◽

Jonathan Robert Arch ◽

David Christopher Hislop ◽

Dominic Anthony Eze ◽

...

Keyword(s):

Insulin Resistance ◽

Blood Glucose ◽

Insulin Sensitivity ◽

Inflammatory Cytokines ◽

Plasma Levels ◽

Low Dose ◽

Tolerance Test ◽

Native Plant ◽

Anti Inflammatory

Background: Salvia officinalis (sage) is a native plant to the Mediterranean region and has been used for a long time in traditional medicine for various diseases. We investigated possible anti-diabetic, anti-inflammatory and anti-obesity effects of sage methanol (MetOH) extract in a nutritional mouse model of obesity, inflammation and insulin resistance, as well as its effects on lipolysis and lipogenesis in 3T3-L1 cells. Methods: Diet-induced obese (DIO) mice were treated for 5 weeks with sage methanol extract (100 and 400 mg.kg -1 /day. bid), or rosiglitazone (3 mg.kg -1 /day. bid), as a positive control. Energy expenditure, food intake, body weight, fat mass, liver glycogen and lipid content were evaluated. Blood glucose, and plasma levels of insulin, lipids leptin and pro- and anti-inflammatory cytokines were measured throughout the experiment. The effects of sage MetOH extract on lipolysis and lipogenesis were tested in vitro in 3T3-L1 cells. Results: After two weeks of treatment, the lower dose of sage MetOH extract decreased blood glucose and plasma insulin levels during an oral glucose tolerance test (OGTT). An insulin tolerance test (ITT), performed at day 29 confirmed that sage improved insulin sensitivity. Groups treated with low dose sage and rosiglitazone showed very similar effects on OGTT and ITT. Sage also improved HOMA-IR, triglycerides and NEFA. Treatment with the low dose increased the plasma levels of the anti-inflammatory cytokines IL-2, IL-4 and IL-10 and reduced the plasma level of the pro-inflammatory cytokines IL-12, TNF-α, and KC/GRO. The GC analysis revealed the presence of two PPARs agonist in sage MetOH extract. In vitro, the extract reduced in a dose-related manner the accumulation of lipid droplets; however no effect on lipolysis was observed. Conclusions: Sage MetOH extract at low dose exhibits similar effects to rosiglitazone. It improves insulin sensitivity, inhibits lipogenesis in adipocytes and reduces inflammation as judged by plasma cytokines. Sage presents an alternative to pharmaceuticals for the treatment of diabetes and associated inflammation.

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Preventive effects of salvia officinalis leaf extract on insulin resistance and inflammation, in high fat diet-induced-obesity mice model

10.7287/peerj.preprints.3086 ◽

2017 ◽

Author(s):

Mohamed Raafet Ben Khedher ◽

Mohamed Hammami ◽

Jonathan Robert Arch ◽

David Christopher Hislop ◽

Dominic Anthony Eze ◽

...

Keyword(s):

Insulin Resistance ◽

Blood Glucose ◽

Insulin Sensitivity ◽

Inflammatory Cytokines ◽

Plasma Levels ◽

Low Dose ◽

Tolerance Test ◽

Native Plant ◽

Anti Inflammatory

Background: Salvia officinalis (sage) is a native plant to the Mediterranean region and has been used for a long time in traditional medicine for various diseases. We investigated possible anti-diabetic, anti-inflammatory and anti-obesity effects of sage methanol (MetOH) extract in a nutritional mouse model of obesity, inflammation and insulin resistance, as well as its effects on lipolysis and lipogenesis in 3T3-L1 cells. Methods: Diet-induced obese (DIO) mice were treated for 5 weeks with sage methanol extract (100 and 400 mg.kg -1 /day. bid), or rosiglitazone (3 mg.kg -1 /day. bid), as a positive control. Energy expenditure, food intake, body weight, fat mass, liver glycogen and lipid content were evaluated. Blood glucose, and plasma levels of insulin, lipids leptin and pro- and anti-inflammatory cytokines were measured throughout the experiment. The effects of sage MetOH extract on lipolysis and lipogenesis were tested in vitro in 3T3-L1 cells. Results: After two weeks of treatment, the lower dose of sage MetOH extract decreased blood glucose and plasma insulin levels during an oral glucose tolerance test (OGTT). An insulin tolerance test (ITT), performed at day 29 confirmed that sage improved insulin sensitivity. Groups treated with low dose sage and rosiglitazone showed very similar effects on OGTT and ITT. Sage also improved HOMA-IR, triglycerides and NEFA. Treatment with the low dose increased the plasma levels of the anti-inflammatory cytokines IL-2, IL-4 and IL-10 and reduced the plasma level of the pro-inflammatory cytokines IL-12, TNF-α, and KC/GRO. The GC analysis revealed the presence of two PPARs agonist in sage MetOH extract. In vitro, the extract reduced in a dose-related manner the accumulation of lipid droplets; however no effect on lipolysis was observed. Conclusions: Sage MetOH extract at low dose exhibits similar effects to rosiglitazone. It improves insulin sensitivity, inhibits lipogenesis in adipocytes and reduces inflammation as judged by plasma cytokines. Sage presents an alternative to pharmaceuticals for the treatment of diabetes and associated inflammation.

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Hypoglycemic effects and mechanisms of electroacupuncture on insulin resistance

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00465.2013 ◽

2014 ◽

Vol 307 (3) ◽

pp. R332-R339 ◽

Cited By ~ 8

Author(s):

Jieyun Yin ◽

Jian Kuang ◽

Manisha Chandalia ◽

Demidmaa Tuvdendorj ◽

Batbayar Tumurbaatar ◽

...

Keyword(s):

Insulin Resistance ◽

Fatty Acid ◽

Blood Glucose ◽

Insulin Sensitivity ◽

Free Fatty Acid ◽

Glucose Tolerance ◽

High Fat Diet ◽

Postprandial Glucose ◽

Tolerance Test ◽

High Fat

The aim of this study was to investigate effects and mechanisms of electroacupuncture (EA) on blood glucose and insulin sensitivity in mice fed a high-fat diet. Both wild-type (WT) and adipose ectonucleotide pyrophosphate phosphodiesterase (ENPP1) transgenic (TG) mice were fed a high-fat diet for 12 wk; for each mouse, an intraperitoneal glucose tolerance test (IPGTT) and insulin tolerance test (ITT) were performed with or without EA at abdomen or auricular areas. A high-fat diet-induced insulin resistance in both WT and TG mice. In the WT mice, EA at 3 Hz and 15 Hz, but not at 1 Hz or 100 Hz, via CV4+CV12 significantly reduced postprandial glucose levels; EA at 3 Hz was most potent. The glucose level was reduced by 61.7% at 60 min and 74.5% at 120 min with EA at 3 Hz (all P < 0.001 vs. control). Similar hypoglycemic effect was noted in the TG mice. On the contrary, EA at auricular points increased postprandial glucose level ( P < 0.03). 4). EA at 3 Hz via CV4+CV12 significantly enhanced the decrease of blood glucose after insulin injection, suggesting improvement of insulin sensitivity. Plasma free fatty acid was significantly suppressed by 42.5% at 15 min and 50.8% at 30 min with EA ( P < 0.01) in both WT and TG mice. EA improves glucose tolerance in both WT and TG mice fed a high-fat diet, and the effect is associated with stimulation parameters and acupoints and is probably attributed to the reduction of free fatty acid.

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Postbiotics for NOD2 require nonhematopoietic RIPK2 to improve blood glucose and metabolic inflammation in mice

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00033.2020 ◽

2020 ◽

Vol 318 (4) ◽

pp. E579-E585 ◽

Cited By ~ 5

Author(s):

Joseph F. Cavallari ◽

Nicole G. Barra ◽

Kevin P. Foley ◽

Amanda Lee ◽

Brittany M. Duggan ◽

...

Keyword(s):

Insulin Resistance ◽

Blood Glucose ◽

Metabolic Diseases ◽

Hematopoietic Cells ◽

Tolerance Test ◽

Whole Body ◽

Glucose Lowering ◽

Endotoxin Challenge ◽

Metabolic Inflammation ◽

Anti Inflammatory

Defining the host receptors and metabolic consequences of bacterial components can help explain how the microbiome influences metabolic diseases. Bacterial peptidoglycans that activate nucleotide-binding oligomerization domain-containing (NOD)1 worsen glucose control, whereas NOD2 activation improves glycemia. Receptor-interacting serine/threonine-protein kinase 2 (RIPK2) is required for innate immunity instigated by NOD1 and NOD2. The role of RIPK2 in the divergent effects of NOD1 versus NOD2 on blood glucose was unknown. We found that whole body deletion of RIPK2 negated all effects of NOD1 or NOD2 activation on blood glucose during an acute, low level endotoxin challenge in mice. It was known that NOD1 in hematopoietic cells participates in insulin resistance and metabolic inflammation in obese mice. It was unknown if RIPK2 in hematopoietic cells is required for the glucose-lowering and anti-inflammatory effects of NOD2 activation. We hypothesized that RIPK2 in nonhematopoietic cells dictated the glycemic effects of NOD2 activation. We found that whole body deletion of RIPK2 prevented the glucose-lowering effects of repeated NOD2 activation that were evident during a glucose tolerance test (GTT) in high-fat diet (HFD)-fed wild-type (WT) mice. NOD2 activation lowered glucose during a GTT and lowered adipose tissue inflammation in mice with RIPK2 deleted in hematopoietic cells. We conclude that RIPK2 in nonhematopoietic cells mediates the glucose lowering and anti-inflammatory effects of NOD2-activating postbiotics. We propose a model where lipopolysaccharides and NOD1 ligands synergize in hematopoietic cells to promote insulin resistance but NOD2 activation in nonhematopoietic cells promotes RIPK2-dependent immune tolerance and lowering of inflammation and insulin resistance.

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A new antidiabetic compound attenuates inflammation and insulin resistance in Zucker diabetic fatty rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00668.2009 ◽

2010 ◽

Vol 298 (5) ◽

pp. E1036-E1048 ◽

Cited By ~ 30

Author(s):

Min Lu ◽

David Patsouris ◽

Pingping Li ◽

Jaime Flores-Riveros ◽

James M. Frincke ◽

...

Keyword(s):

Insulin Resistance ◽

Adipose Tissue ◽

Insulin Sensitivity ◽

Hepatic Glucose Production ◽

Liver Cholesterol ◽

Total Serum ◽

Total Serum Cholesterol ◽

Zucker Diabetic Fatty Rats ◽

Anti Inflammatory

Tissue macrophage inflammatory pathways contribute to obesity-associated insulin resistance. Here, we have examined the efficacy and mechanisms of action of a novel anti-inflammatory compound (HE3286) in vitro and in vivo. In primary murine macrophages, HE3286 attenuates LPS- and TNFα-stimulated inflammation. In Zucker diabetic fatty rats, inflammatory cytokine/chemokine expression was downregulated in liver and adipose tissue by HE3286 treatment, as was macrophage infiltration into adipose tissue. In line with reduced inflammation, HE3286 treatment normalized fasting and fed glucose levels, improved glucose tolerance, and enhanced skeletal muscle and liver insulin sensitivity, as assessed by hyperinsulinemic euglycemic clamp studies. In phase 2 clinical trials, HE3286 treatment led to an enhancement in insulin sensitivity in humans. Gluconeogenic capacity was also reduced by HE3286 treatment, as evidenced by a reduced glycemic response during pyruvate tolerance tests and decreased basal hepatic glucose production (HGP) rates. Since serum levels of gluconeogenic substrates were decreased by HE3286, it indicates that the reduction of both intrinsic gluconeogenic capacity and substrate availability contributes to the decrease in HGP. Lipidomic analysis revealed that HE3286 treatment reduced liver cholesterol and triglyceride content, leading to a feedback elevation of LDL receptor and HMG-CoA reductase expression. Accordingly, HE3286 treatment markedly decreased total serum cholesterol. In conclusion, HE3286 is a novel anti-inflammatory compound, which displays both glucose-lowering and cholesterol-lowering effects.

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Dose and Dose Rate-Dependent Effects of Low-Dose Irradiation on Inflammatory Parameters in ApoE-Deficient and Wild Type Mice

Cells ◽

10.3390/cells10113251 ◽

2021 ◽

Vol 10 (11) ◽

pp. 3251

Author(s):

Annegret Glasow ◽

Ina Patties ◽

Nicholas D. Priest ◽

Ronald E. J. Mitchel ◽

Guido Hildebrandt ◽

...

Keyword(s):

Dose Rate ◽

Plasma Levels ◽

Low Dose ◽

Time Dependent ◽

Whole Body ◽

Wild Type ◽

Adhesion Properties ◽

Dose Rates ◽

Anti Inflammatory

Anti-inflammatory low-dose therapy is well established, whereas the immunomodulatory impact of doses below 0.1 Gy is much less clear. In this study, we investigated dose, dose rate and time-dependent effects in a dose range of 0.005 to 2 Gy on immune parameters after whole body irradiation (IR) using a pro-inflammatory (ApoE−/−) and a wild type mouse model. Long-term effects on spleen function (proliferation, monocyte expression) were analyzed 3 months, and short-term effects on immune plasma parameters (IL6, IL10, IL12p70, KC, MCP1, INFγ, TGFβ, fibrinogen, sICAM, sVCAM, sE-selectin/CD62) were analyzed 1, 7 and 28 days after Co60 γ-irradiation (IR) at low dose rate (LDR, 0.001 Gy/day) and at high dose rate (HDR). In vitro measurements of murine monocyte (WEHI-274.1) adhesion and cytokine release (KC, MCP1, IL6, TGFβ) after low-dose IR (150 kV X-ray unit) of murine endothelial cell (EC) lines (H5V, mlEND1, bEND3) supplement the data. RT-PCR revealed significant reduction of Ki67 and CD68 expression in the spleen of ApoE−/− mice after 0.025 to 2 Gy exposure at HDR, but only after 2 Gy at LDR. Plasma levels in wild type mice, showed non-linear time-dependent induction of proinflammatory cytokines and reduction of TGFβ at doses as low as 0.005 Gy at both dose rates, whereas sICAM and fibrinogen levels changed in a dose rate-specific manner. In ApoE−/−−/− mice, levels of sICAM increased and fibrinogen decreased at both dose rates, whereas TGFβ increased mainly at HDR. Non-irradiated plasma samples revealed significant age-related enhancement of cytokines and adhesion molecules except for sICAM. In vitro data indicate that endothelial cells may contribute to systemic IR effects and confirm changes of adhesion properties suggested by altered sICAM plasma levels. The differential immunomodulatory effects shown here provide insights in inflammatory changes occurring at doses far below standard anti-inflammatory therapy and are of particular importance after diagnostic and chronic environmental exposures.

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Soluble TIM3 and Its Ligands Galectin-9 and CEACAM1 Are in Disequilibrium During Alcohol-Related Liver Disease and Promote Impairment of Anti-bacterial Immunity

Frontiers in Physiology ◽

10.3389/fphys.2021.632502 ◽

2021 ◽

Vol 12 ◽

Author(s):

Antonio Riva ◽

Elena Palma ◽

Dhruti Devshi ◽

Douglas Corrigall ◽

Huyen Adams ◽

...

Keyword(s):

Liver Disease ◽

Disease Severity ◽

Inflammatory Cytokines ◽

Bacterial Translocation ◽

Whole Blood ◽

Plasma Levels ◽

Bacterial Challenge ◽

Anti Inflammatory ◽

Related Liver Disease

Background and AimsImmunoregulatory checkpoint receptors (CR) contribute to the profound immunoparesis observed in alcohol-related liver disease (ALD) and in vitro neutralization of inhibitory-CRs TIM3/PD1 on anti-bacterial T-cells can rescue innate and adaptive anti-bacterial immunity. Recently described soluble-CR forms can modulate immunity in inflammatory conditions, but the contributions of soluble-TIM3 and soluble-PD1 and other soluble-CRs to immune derangements in ALD remain unclear.MethodsIn Alcoholic Hepatitis (AH; n = 19), alcohol-related cirrhosis (ARC; n = 53) and healthy control (HC; n = 27) subjects, we measured by Luminex technology (i) plasma levels of 16 soluble-CRs, 12 pro/anti-inflammatory cytokines and markers of gut bacterial translocation; (ii) pre-hepatic, post-hepatic and non-hepatic soluble-CR plasma levels in ARC patients undergoing TIPS; (iii) soluble-CRs production from ethanol-treated immunocompetent precision cut human liver slices (PCLS); (iv) whole-blood soluble-CR expression upon bacterial challenge. By FACS, we assessed the relationship between soluble-TIM3 and membrane-TIM3 and rescue of immunity in bacterial-challenged PBMCs.ResultsSoluble-TIM3 was the dominant plasma soluble-CR in ALD vs. HC (p = 0.00002) and multivariate analysis identified it as the main driver of differences between groups. Soluble-CRs were strongly correlated with pro-inflammatory cytokines, gut bacterial translocation markers and clinical indices of disease severity. Ethanol exposure or bacterial challenge did not induce soluble-TIM3 production from PCLS nor from whole-blood. Bacterial challenge prompted membrane-TIM3 hyperexpression on PBMCs from ALD patient’s vs. HC (p < 0.002) and was inversely correlated with plasma soluble-TIM3 levels in matched patients. TIM3 ligands soluble-Galectin-9 and soluble-CEACAM1 were elevated in ALD plasma (AH > ARC; p < 0.002). In vitro neutralization of Galectin-9 and soluble-CEACAM1 improved the defective anti-bacterial and anti-inflammatory cytokine production from E. coli-challenged PBMCs in ALD patients.ConclusionsAlcohol-related liver disease patients exhibit supra-physiological plasma levels of soluble-TIM3, particularly those with greater disease severity. This is also associated with increased levels of soluble TIM3-ligands and membrane-TIM3 expression on immune cells. Soluble-TIM3 can block the TIM3-ligand synapse and improve anti-bacterial immunity; however, the increased levels of soluble TIM3-binding ligands in patients with ALD negate any potential immunostimulatory effects. We believe that anti-TIM3 neutralizing antibodies currently in Phase I clinical trials or soluble-TIM3 should be investigated further for their ability to enhance anti-bacterial immunity. These agents could potentially represent an innovative immune-based supportive approach to rescue anti-bacterial defenses in ALD patients.

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Effects of Overexpression of Neurosecretory Protein GL-Precursor Gene on Glucose Homeostasis and Insulin Sensitivity in Mice

International Journal of Molecular Sciences ◽

10.3390/ijms22094681 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4681

Author(s):

Keisuke Fukumura ◽

Yuki Narimatsu ◽

Shogo Moriwaki ◽

Eiko Iwakoshi-Ukena ◽

Megumi Furumitsu ◽

...

Keyword(s):

Insulin Resistance ◽

Blood Glucose ◽

Insulin Sensitivity ◽

Glucose Homeostasis ◽

Mass Gain ◽

Tolerance Test ◽

Oral Glucose ◽

Insulin Levels ◽

Glucose Levels ◽

Increase Food Intake

A high-fat diet (HFD) quickly induces obesity with insulin resistance and hyperglycemia. We previously reported that a novel hypothalamic small protein, named neurosecretory protein GL (NPGL), stimulates feeding and fat accumulation in mice. However, the effects of NPGL on insulin sensitivity and glucose homeostasis remain unknown. Hence, we subjected NPGL-precursor gene (Npgl)-overexpressing mice to the oral glucose tolerance test (OGTT) and intraperitoneal insulin tolerance test (IPITT) under normal chow (NC) and HFD conditions. Npgl overexpression promoted body mass gain and tended to increase food intake of NC-fed mice, whereas it had little effect on HFD-fed mice. The OGTT showed elevated blood glucose and insulin levels in Npgl-overexpressing NC-fed mice 15 min after glucose administration. Both the OGTT and IPITT demonstrated that Npgl overexpression decreased blood glucose levels in HFD-fed mice 60 min after glucose and insulin treatments. Notably, Npgl overexpression increased adipose tissue masses only in NC-fed mice, and it decreased blood glucose and insulin levels in HFD-fed mice at the experimental end point. It also increased the mRNA expression of galanin, one of the feeding and metabolic regulatory neuropeptides, in the hypothalamus of HFD-fed mice. Therefore, NPGL may alleviate HFD-induced hyperglycemia and insulin resistance in mice.

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AAnti-Inflammatory Effects of Plasma Circulating Exosomes Obtained from Normal-Weight and Obese Subjects on Hepatocytes

Endocrine Metabolic & Immune Disorders - Drug Targets ◽

10.2174/1871530320666200505121426 ◽

2020 ◽

Vol 20 ◽

Author(s):

Reza Afrisham ◽

Sahar Sadegh-Nejadi ◽

Reza Meshkani ◽

Solaleh Emamgholipour ◽

Molood Bagherieh ◽

...

Keyword(s):

Inflammatory Cytokines ◽

Hepg2 Cells ◽

Human Liver ◽

Liver Cells ◽

Normal Weight ◽

Protein Levels ◽

Human Liver Cells ◽

Tnf Α ◽

Anti Inflammatory

Introduction: Obesity is a disorder with low-grade chronic inflammation that plays a key role in the hepatic inflammation and steatosis. Moreover, there are studies to support the role of exosomes in the cellular communications, the regulation of metabolic homeostasis and immunomodulatory activity. Accordingly, we aimed to evaluate the influence of plasma circulating exosomes derived from females with normal-weight and obesity on the secretion of inflammatory cytokines in human liver cells. Methods: Plasma circulating exosomes were isolated from four normal (N-Exo) and four obese (O-Exo) women. The exosomes were characterized and approved for CD63 expression (common exosomal protein marker) and morphology/size using the western blot and TEM methods, respectively. The exosomes were used for stimulation of HepG2 cells in vitro. After 24 h incubation, the protein levels of TNF-α,IL-6, and IL-1β were measured in the culture supernatant of HepG2 cells using the ELISA kit. Results: The protein levels of IL-6 and TNF-α in the cells treated with O-Exo and N-Exo reduced significantly in comparison with control group (P=0.039 and P<0.001 respectively), while significance differences were not found between normal and obese groups (P=0.808, and P=0.978 respectively). However, no significant differences were found between three groups in term of IL-1β levels (P=0.069). Based on the correlation analysis, the protein levels of IL-6 were positively correlated with TNF-α (r 0.978, P<0.001). Conclusion: These findings suggest that plasma circulating exosomes have probably anti-inflammatory properties independently from body mass index and may decrease the secretion of inflammatory cytokines in liver. However, further investigations in vitro and in vivo are needed to address the anti-inflammatory function of N-Exo and O-Exo in human liver cells and/or other cells.

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N-palmitoyl-D-glucosamine, A Natural Monosaccharide-Based Glycolipid, Inhibits TLR4 and Prevents LPS-Induced Inflammation and Neuropathic Pain in Mice

International Journal of Molecular Sciences ◽

10.3390/ijms22031491 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1491 ◽

Cited By ~ 1

Author(s):

Monica Iannotta ◽

Carmela Belardo ◽

Maria Consiglia Trotta ◽

Fabio Arturo Iannotti ◽

Rosa Maria Vitale ◽

...

Keyword(s):

Sciatic Nerve ◽

Inflammatory Cytokines ◽

Lipid A ◽

Saturated Fatty Acids ◽

Structural Similarity ◽

Antagonistic Activity ◽

Critical Function ◽

Anti Inflammatory

Toll-like receptors (TLRs) are key receptors through which infectious and non-infectious challenges act with consequent activation of the inflammatory cascade that plays a critical function in various acute and chronic diseases, behaving as amplification and chronicization factors of the inflammatory response. Previous studies have shown that synthetic analogues of lipid A based on glucosamine with few chains of unsaturated and saturated fatty acids, bind MD-2 and inhibit TLR4 receptors. These synthetic compounds showed antagonistic activity against TLR4 activation in vitro by LPS, but little or no activity in vivo. This study aimed to show the potential use of N-palmitoyl-D-glucosamine (PGA), a bacterial molecule with structural similarity to the lipid A component of LPS, which could be useful for preventing LPS-induced tissue damage or even peripheral neuropathies. Molecular docking and molecular dynamics simulations showed that PGA stably binds MD-2 with a MD-2/(PGA)3 stoichiometry. Treatment with PGA resulted in the following effects: (i) it prevented the NF-kB activation in LPS stimulated RAW264.7 cells; (ii) it decreased LPS-induced keratitis and corneal pro-inflammatory cytokines, whilst increasing anti-inflammatory cytokines; (iii) it normalized LPS-induced miR-20a-5p and miR-106a-5p upregulation and increased miR-27a-3p levels in the inflamed corneas; (iv) it decreased allodynia in peripheral neuropathy induced by oxaliplatin or formalin, but not following spared nerve injury of the sciatic nerve (SNI); (v) it prevented the formalin- or oxaliplatin-induced myelino-axonal degeneration of sciatic nerve. SIGNIFICANCE STATEMENT We report that PGA acts as a TLR4 antagonist and this may be the basis of its potent anti-inflammatory activity. Being unique because of its potency and stability, as compared to other similar congeners, PGA can represent a tool for the optimization of new TLR4 modulating drugs directed against the cytokine storm and the chronization of inflammation.

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