Resolution of inflammation: therapeutic potential of pro-resolving lipids in type 2 diabetes mellitus and associated renal complications

Cardiovascular/Stroke Risk Stratification in Diabetic Foot Infection Patients Using Deep Learning-Based Artificial Intelligence: An Investigative Study

A diabetic foot infection (DFI) is among the most serious, incurable, and costly to treat conditions. The presence of a DFI renders machine learning (ML) systems extremely nonlinear, posing difficulties in CVD/stroke risk stratification. In addition, there is a limited number of well-explained ML paradigms due to comorbidity, sample size limits, and weak scientific and clinical validation methodologies. Deep neural networks (DNN) are potent machines for learning that generalize nonlinear situations. The objective of this article is to propose a novel investigation of deep learning (DL) solutions for predicting CVD/stroke risk in DFI patients. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) search strategy was used for the selection of 207 studies. We hypothesize that a DFI is responsible for increased morbidity and mortality due to the worsening of atherosclerotic disease and affecting coronary artery disease (CAD). Since surrogate biomarkers for CAD, such as carotid artery disease, can be used for monitoring CVD, we can thus use a DL-based model, namely, Long Short-Term Memory (LSTM) and Recurrent Neural Networks (RNN) for CVD/stroke risk prediction in DFI patients, which combines covariates such as office and laboratory-based biomarkers, carotid ultrasound image phenotype (CUSIP) lesions, along with the DFI severity. We confirmed the viability of CVD/stroke risk stratification in the DFI patients. Strong designs were found in the research of the DL architectures for CVD/stroke risk stratification. Finally, we analyzed the AI bias and proposed strategies for the early diagnosis of CVD/stroke in DFI patients. Since DFI patients have an aggressive atherosclerotic disease, leading to prominent CVD/stroke risk, we, therefore, conclude that the DL paradigm is very effective for predicting the risk of CVD/stroke in DFI patients.

Impaired brown adipose tissue is differentially modulated in insulin-resistant obese wistar and type 2 diabetic Goto-Kakizaki rats

Brown adipose tissue (BAT) is a potential target to treat obesity and diabetes, dissipating energy as heat. Type 2 diabetes (T2D) has been associated with obesogenic diets; however, T2D was also reported in lean individuals to be associated with genetic factors. We aimed to investigate the differences between obese and lean models of insulin resistance (IR) and elucidate the mechanism associated with BAT metabolism and dysfunction in different IR animal models: a genetic model (lean GK rats) and obese models (diet-induced obese Wistar rats) at 8 weeks of age fed a high-carbohydrate (HC), high-fat (HF) diet, or high-fat and high-sugar (HFHS) diet for 8 weeks. At 15 weeks of age, BAT glucose uptake was evaluated by 18F-FDG PET under basal (saline administration) or stimulated condition (CL316,243, a selective β3-AR agonist). After CL316, 243 administrations, GK animals showed decreased glucose uptake compared to HC animals. At 16 weeks of age, the animals were euthanized, and the interscapular BAT was dissected for analysis. Histological analyses showed lower cell density in GK rats and higher adipocyte area compared to all groups, followed by HFHS and HF compared to HC. HFHS showed a decreased batokine FGF21 protein level compared to all groups. However, GK animals showed increased expression of genes involved in fatty acid oxidation (CPT1 and CPT2), BAT metabolism (Sirt1 and Pgc1-α), and obesogenic genes (leptin and PAI-1) but decreased gene expression of glucose transporter 1 (GLUT-1) compared to other groups. Our data suggest impaired BAT function in obese Wistar and GK rats, with evidence of a whitening process in these animals.

Lipoxins and synthetic lipoxin mimetics: Therapeutic potential in renal diseases

Inflammation and its timely resolution are critical to ensuring effective host defence and appropriate tissue repair after injury. Unresolved inflammation typifies many renal pathologies. The key drivers of the inflammatory response are well defined and targeted by conventional anti-inflammatory therapeutics. However, these are associated with undesirable side effects including immune suppression. More recently, there is growing appreciation that specialized lipid mediators [SPMs] including lipoxins promote the resolution of inflammation and endogenous repair mechanisms without compromising host defence. We discuss the pro-resolving bioactions of lipoxins and recent work that aims to harness their therapeutic potential in the context of kidney disease.

Actions of annatto-extracted tocotrienol supplementation on obese postmenopausal women: study protocol for a double-blinded, placebo-controlled, randomised trial

INTRODUCTION

Obesity is a major health concern in postmenopausal women, and chronic low-grade inflammation contributes to the development of obesity. Cellular studies and high-fat-diet-induced obese mouse model mimicking obesity show the antiobesity effect of annatto-extracted tocotrienols (TT) with antioxidant capability. We aim to assess the safety and efficacy of TT consumption for lipid-related parameters in obese postmenopausal women.

METHODS AND ANALYSIS

Eligible obese postmenopausal women will be randomly assigned to placebo group (430 mg olive oil) and TT group (DeltaGold Tocotrienol 70%) for 24 weeks. In the present study, the primary outcome is total/regional fat mass and visceral adipose tissue. The secondary outcomes include lipid profile in serum, mRNA expression of fatty acid synthase and carnitine palmitoyltransferase 1A in fat tissue, oxylipins and endocannabinoids in plasma and adipose tissue, abundance and composition of intestinal microbiome in faeces, high-sensitivity C-reactive protein (hs-CRP) in serum and leptin in serum. Every participant will be evaluated at 0 (prior to starting intervention) and 24 weeks of intervention, except for serum lipid profile and hs-CRP at 0, 12 and 24 weeks. 'Intent-to-treat' principle is employed for data analysis. Hierarchical linear modelling is used to estimate the effects of dietary TT supplementation while properly accounting for dependency of data and identified covariates. To our knowledge, this is the first randomised, placebo-controlled, double-blinded study to determine dietary TT supplementation on an obese population. If successful, this study will guide the future efficacy TT interventions and TT can be implemented as an alternative for obese population in antiobesity management.

ETHICS AND DISSEMINATION

This study has been approved by the Bioethics Committee of the Texas Tech University Health Sciences Center, Lubbock. An informed consent form will be signed by a participant before enrolling in the study. The results from this trial will be actively disseminated through academic conference presentation and peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03705845.

The prospective curative role of lipoxin A4 in induced gastric ulcer in rats: Possible involvement of mitochondrial dynamics signaling pathway

This study purposed to examine the prospective curative role of lipoxin A₄ (LXA₄ ) in induced gastric ulcer in rats and explore the possible involvement of mitochondrial dynamics signaling pathway. Forty-eight male Wistar rats were divided into four groups: control, indomethacin (IND), IND + omeprazole (IND + Omez), and IND+ LXA₄ groups. At the end of the experiment, the gastric pH, gastric fluid volume, total gastric acidity, ulcer index, and curative index were estimated. The gene expression of mitochondrial related protein 1 and mitofusin 2 were determined. In addition, some mitochondrial parameters include mitochondrial transmembrane potential, complex-I activity and reactive oxygen species were measured. Also, some gastric biochemical parameters, histopathological, and immunohistochemical analyses of the gastric mucosa were determined. We found that IND induced gastric ulcer, as manifested by the biochemical, histopathological, and immunohistochemical analyses. Both Omez and LXA₄ treatment for 15 days alleviated the IND-induced gastric ulcer as explored by ameliorating the biochemical, histopathological, and immunohistochemical findings. We concluded that LXA₄ mitigated the IND-induced gastric ulcer via improving the mitochondrial dynamic imbalance and mitochondrial dysfunction, in addition to its anti-apoptotic, anti-inflammatory, and antioxidant properties.

Therapeutic Potential of Lipoxin A4 in Chronic Inflammation: Focus on Cardiometabolic Disease

Several studies have shown that failure to resolve inflammation may contribute to the progression of many chronic inflammatory disorders. It has been suggested targeting the resolution of inflammation might be a novel therapeutic approach for chronic inflammatory diseases, including inflammatory bowel disease, diabetic complications, and cardiometabolic disease. Lipoxins [LXs] are a class of endogenously generated mediators that promote the resolution of inflammation. Biological actions of LXs include inhibition of neutrophil infiltration, promotion of macrophage polarization, increase of macrophage efferocytosis, and restoration of tissue homeostasis. Recently, several studies have demonstrated that LXs and synthetic analogues protect tissues from acute and chronic inflammation. The mechanism includes down-regulation of pro-inflammatory cytokines and chemokines (e.g., interleukin-1β and tumor necrosis factor-α), inhibition of the activation of the master pro-inflammatory pathway (e.g., nuclear factor κ-light-chain-enhancer of activated B cells pathway) and increased release of the pro-resolving cytokines (e.g., interleukin-10). Three generations of LXs analogues are well described in the literature, and more recently a fourth generation has been generated that appears to show enhanced potency. In this review, we will briefly discuss the potential therapeutic opportunity provided by lipoxin A₄ as a novel approach to treat chronic inflammatory disorders, focusing on cardiometabolic disease and the current drug development in this area.

The effect of western diet on mice brain lipid composition

Background

The appropriate fatty acids composition of brain lipids is critical for functioning of this organ. The alterations of brain fatty acids composition may lead to neurological and neurodegenerative diseases.

Methods

The aim of this work was to evaluate the effect of western diet containing high fat content on fatty acid composition of brain lipids. In this study we used mice fed high fat diet (HFD) for 19 weeks. Brain lipids were separated by SPE extraction and fatty acid composition in chow, mice serum, brain and other tissues was analyzed by GC-MS method.

Results

The body weight and adipose tissue weigh of mice after HFD increased significantly. The concentrations of most of fatty acids in serum of mice after HFD increased, due to their higher delivery from food. Unexpectedly the serum eicosapentaenoic acid (EPA) concentration was lower in mice after HFD than in controls. Also the brain, and other tissue EPA content was lower. Among studied groups of brain lipids EPA was significantly decreased in phospholipids and sphingolipids.

Conclusions

Considering important role of brain EPA including maintaining of appropriate composition of cell membrane lipids and anti-inflammatory properties we conclude that decrease of brain EPA after western diet may result in impaired brain function.

Anti-inflammatory effects of resolvins in diabetic nephropathy: Mechanistic pathways

The incidence of diabetes mellitus is growing rapidly. The exact pathophysiology of diabetes is unclear, but there is increasing evidence of the role of the inflammatory response in both developing diabetes as well as its complications. Resolvins are naturally occurring polyunsaturated fatty acids that are found in fish oil and sea food that have been shown to possess anti-inflammatory actions in several tissues including the kidneys. The pathways by which resolvins exert this anti-inflammatory effect are unclear. In this review we discuss the evidence showing that resolvins can suppress inflammatory responses via at least five molecular mechanisms through inhibition of the nucleotide-binding oligomerization domain protein 3 inflammasome, inhibition of nuclear factor κB molecular pathways, improvement of oxidative stress, modulation of nitric oxide synthesis/release and prevention of local and systemic leukocytosis. Complete understanding of these molecular pathways is important as this may lead to the development of new effective therapeutic strategies for diabetes and diabetic nephropathy.

Mesenchymal Stem Cells Reverse Diabetic Nephropathy Disease via Lipoxin A4 by Targeting Transforming Growth Factor β (TGF-β)/smad Pathway and Pro-Inflammatory Cytokines

BACKGROUND Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. Mesenchymal stem cells (MSCs) treatment has been proved to be effective in DN models by protecting renal function and preventing fibrosis. However, the underlying mechanism is unclear. Previous research indicated diabetes and associated complications may be attributed to failed resolution of inflammation, which is deliberately regulated by pro-resolving lipids, including lipoxins (LXs), resolvins (Rv) D and E series, protectins, and maresins. In this study, we monitored pro-resolving mediators in a DN model to explore the mechanism of MSCs treatment. MATERIAL AND METHODS The DN model was induced by STZ injection in SD rats. UPLC-MS/MS was performed to determine pro-resolving lipids in kidney tissue and serum of DN model before and after MSCs treatment, as well as in supernatants of HBZY-1-MSCs co-culture. RESULTS LXA4 was highly accumulated in renal tissue of DN rats with MSCs treatment; ex vivo, LXA4 was significantly increased in the supernatants of HBZY-1 cells co-cultured with MSCs in a high-glucose (HG) medium. Western blot analysis indicated that ALX/FPR2, the receptor of LXA4, was markedly expressed in renal tissue of the DN-MSC group and HBZY-1 after incubating with MSCs in HG. Intraperitoneal injection of LXA4 inhibited renal fibrosis by targeting TGF-ß/Smad signaling and downregulated serum TNF-alpha, IL-6, IL-8, and IFN-γ in DN rats. Notably, all the protective effects induced by MSCs or LXA4 were abolished by ALX/FRP2 blocking. CONCLUSIONS Our results demonstrate that MSCs intervention prevented DN procession via the LXA4-ALX/FPR2 axis, which inhibited glomerulosclerosis and pro-inflammatory cytokines, eventually contributing to kidney homeostasis.

New pro-resolving n-3 mediators bridge resolution of infectious inflammation to tissue regeneration

While protective, the acute inflammatory response when uncontrolled can lead to further tissue damage and chronic inflammation that is now widely recognized to play important roles in many commonly occurring diseases, such as cardiovascular disease, neurodegenerative diseases, metabolic syndrome, and many other diseases of significant public health concern. The ideal response to initial challenges of the host is complete resolution of the acute inflammatory response, which is now recognized to be a biosynthetically active process governed by specialized pro-resolving mediators (SPM). These chemically distinct families include lipoxins, resolvins, protectins and maresins that are biosynthesized from essential fatty acids. The biosynthesis and complete stereochemical assignments of the major SPM are established, and new profiling procedures have recently been introduced to document the activation of these pathways in vivo with isolated cells and in human tissues. The active resolution phase leads to tissue regeneration, where we've recently identified new molecules that communicate during resolution of inflammation to activate tissue regeneration in model organisms. This review presents an update on the documentation of the roles of SPMs and the biosynthesis and structural elucidation of novel mediators that stimulate tissue regeneration, coined conjugates in tissue regeneration. The identification and actions of the three families, maresin conjugates in tissue regeneration (MCTR), protectin conjugates in tissue regeneration (PCTR), and resolvin conjugates in tissue regeneration (RCTR), are reviewed here. The identification, structural elucidation and the pathways and biosynthesis of these new mediators in tissue regeneration demonstrate the host capacity to protect from collateral tissue damage, stimulate clearance of bacteria and debris, and promote tissue regeneration via endogenous pathways and molecules in the resolution metabolome.

Lipoxins Protect Against Inflammation in Diabetes-Associated Atherosclerosis

Increasing evidence points to the fact that defects in the resolution of inflammatory pathways predisposes individuals to the development of chronic inflammatory diseases, including diabetic complications such as accelerated atherosclerosis. The resolution of inflammation is dynamically regulated by the production of endogenous modulators of inflammation, including lipoxin A4 (LXA₄). Here, we explored the therapeutic potential of LXA₄ and a synthetic LX analog (Benzo-LXA₄) to modulate diabetic complications in the streptozotocin-induced diabetic ApoE^-/- mouse and in human carotid plaque tissue ex vivo. The development of diabetes-induced aortic plaques and inflammatory responses of aortic tissue, including the expression of vcam-1, mcp-1, il-6, and il-1β, was significantly attenuated by both LXA₄ and Benzo-LXA₄ in diabetic ApoE^-/- mice. Importantly, in mice with established atherosclerosis, treatment with LXs for a 6-week period, initiated 10 weeks after diabetes onset, led to a significant reduction in aortic arch plaque development (19.22 ± 2.01% [diabetic]; 12.67 ± 1.68% [diabetic + LXA₄]; 13.19 ± 1.97% [diabetic + Benzo-LXA₄]). Secretome profiling of human carotid plaque explants treated with LXs indicated changes to proinflammatory cytokine release, including tumor necrosis factor-α and interleukin-1β. LXs also inhibited platelet-derived growth factor-stimulated vascular smooth muscle cell proliferation and transmigration and endothelial cell inflammation. These data suggest that LXs may have therapeutic potential in the context of diabetes-associated vascular complications.

Proresolving protein Annexin A1: The role in type 2 diabetes mellitus and obesity

BACKGROUND

Annexin A1 (AnxA1) is a protein involved in inflammation resolution that might be altered in obesity-associated type 2 diabetes mellitus (DM), which is a chronic inflammatory disease. The aim of this study was to evaluate AnxA1 serum levels in individuals with and without DM stratified according to the body mass index (BMI), and the dynamic of AnxA1 expression in adipose tissue from humans with obesity and non-obesity.

METHODS

Serum samples were obtained from 41 patients with DM (lean, overweight and obese) and 40 controls, and adipose tissue samples were obtained from 16 individuals with obesity (with or without DM), and 15 controls.

RESULTS

DM patients showed similar AnxA1 serum levels when compared to controls. However, when the individuals were stratified according to BMI, AnxA1 levels were higher in individuals with obesity than lean or overweight, and in overweight compared to lean individuals. Moreover, AnxA1 was correlated positively with IL-6 levels. AnxA1 levels were also positively correlated with BMI, waist circumference and waist-to-hip ratio. Furthermore, higher levels of cleaved AnxA1 were observed in adipose tissue from individuals with obesity, independently of DM status.

CONCLUSIONS

Enhanced levels of AnxA1 in serum of individuals with obesity suggest an attempt to counter-regulate the systemic inflammation process in this disease. However, the higher levels of cleaved AnxA1 in the adipose tissue of individuals with obesity could compromise its anti-inflammatory and proresolving actions, locally. Considering our data, AnxA1 cleavage in the adipose tissue, despite increased serum levels of this protein, and consequently the failure in inflammation resolution, suggests an important pathophysiological mechanism involved in inflammatory status observed in obesity.

Structural elucidation and physiologic functions of specialized pro-resolving mediators and their receptors

The acute inflammatory response is host-protective to contain foreign invaders. Many of today's pharmacopeia that block pro-inflammatory chemical mediators can cause serious unwanted side effects such as immune suppression. Uncontrolled inflammation is now considered a pathophysiologic basis associated with many widely occurring diseases such as cardiovascular disease, neurodegenerative diseases, diabetes, obesity and asthma, as well as the classic inflammatory diseases, e.g. arthritis, periodontal diseases. The inflammatory response is designated to be a self-limited process that produces a superfamily of chemical mediators that stimulate resolution of inflammatory responses. Specialized proresolving mediators (SPM) uncovered in recent years are endogenous mediators that include omega-3-derived families resolvins, protectins and maresins, as well as arachidonic acid-derived (n-6) lipoxins that stimulate and promote resolution of inflammation, clearance of microbes, reduce pain and promote tissue regeneration via novel mechanisms. Here, we review recent evidence from human and preclinical animal studies, together with the structural and functional elucidation of SPM indicating the SPM as physiologic mediators and pharmacologic agonists that stimulate resolution of inflammation and infection. These results suggest that it is time to develop immunoresolvents as agonists for testing resolution pharmacology in nutrition and health as well as in human diseases and during surgery.

Low dose aspirin increases 15-epi-lipoxin A4 levels in diabetic chronic kidney disease patients

BACKGROUND

Resolution of inflammation is regulated by endogenous lipid mediators, such as lipoxins and their epimers, including 15-epi-lipoxin A4 (15-epi-LXA4). However, there is no information on 15-epi-LXA4 and its in vivo regulation in chronic kidney disease (CKD) patients.

STUDY DESIGN

Open label randomized clinical trial.

SETTING AND PARTICIPANTS

50 participants with chronic kidney disease (CKD) stage 3 and 4 without prior cardiovascular disease (25 in the aspirin group and 25 in the standard group) followed for 46 months.

INTERVENTION

Aspirin (100mg/day) or standard treatment.

AIM

To analyze the effect of aspirin on plasma 15-epi-LXA4 levels and inflammatory markers in CKD patients.

RESULTS

Baseline plasma15-epi-LXA4 levels were lower in diabetic (1.22 ± 0.99ng/ml) than in non-diabetic CKD patients (2.05 ± 1.06ng/ml, p < 0.001) and inversely correlated with glycosylated hemoglobin levels (r = -0.303, p = 0.006). In multivariate analysis, diabetes was associated with lower 15-epi-LXA4 levels, adjusted for age, inflammatory markers and renal function (p = 0.005). In the whole study population, 15-epi-LXA4 levels tended to increase, but not significantly (p = 0.45), after twelve months on aspirin (from mean ± SD 1.84 ± 1.06 to 2.04 ± 0.75ng/ml) and decreased in the standard care group (1.60 ± 1.15 to 1.52 ± 0.68ng/ml, p = 0.04). The aspirin effect on 15-epi-LXA4 levels was more striking in diabetic patients, increasing from 0.94 ± 0.70 to 1.93 ± 0.74ng/ml, p = 0.017.

CONCLUSIONS

Diabetic patients with CKD have lower circulating 15-epi-LXA4 levels than non-diabetic CKD patients. Low dose aspirin for 12 months increased 15-epi-LXA4 levels in diabetic patients. Given its anti-inflammatory properties, this increase in 15-epi-LXA4 levels may contribute to the beneficial effects of low dose aspirin.

MiR-30a targets IL-1α and regulates islet functions as an inflammation buffer and response factor

Diabetes is an inflammatory disease. Inflammation plays an important role in islet functions. However, the exact mechanisms by which inflammation affects islet functions remain unclear. In this study, we investigated the regulatory effects of miR-30a on inflammation and islet functions. The results indicate that miR-30a serves as an inflammation-resolving buffer factor by targeting interleukin 1a (IL-1α) in immune cells and in islet cells, which might play an important role in inflammation homeostasis. miR-30a ameliorates islet functions in an inflammatory micro-environment by targeting the IL-1α/nuclear factor kappa B (NFKB) p65 subunit (p65)/p62 (SQSTM1)/insulin axis, which can be developed into a novel antidiabetic approach. miR-30a serves as a promising inflammation-response biomarker in inflammatory diseases and is possibly activated by the toll-like receptor 4 (TLR4)/IL-1α/NFKB pathways. However, the exact molecular mechanisms by which miR-30a regulates inflammation and islet functions as well as the potential applications in transitional medicine require further elucidation.

Adipocyte lipid storage and adipokine production are modulated by lipoxygenase-derived oxylipins generated from 18-carbon fatty acids

Generation of oxylipins (oxygenated metabolites of fatty acids) by lipoxygenases may be responsible for the beneficial effects of 20- and 22-carbon n-3 fatty acids on adipose tissue dysfunction in obesity, but the potential actions of oxylipins derived from 18-carbon fatty acids, which are generally at higher levels in the diet, are unknown. We therefore compared the effects of select lipoxygenase-derived oxylipins produced from α-linolenic acid (ALA, C18:3 n-3), linoleic acid (LA, C18:2 n-6), and arachidonic acid (AA, C20:4 n-6) on key adipocyte functions that are altered in obesity. Individual oxylipins were added to the culture medium of differentiating 3T3-L1 preadipocytes for 6days. Lipid accumulation was subsequently determined by Oil Red O staining, while Western blotting was used to measure levels of proteins associated with lipid metabolism and characteristics of adipocyte functionality. Addition of all oxylipins at 30nM was sufficient to significantly decrease triglyceride accumulation in lipid droplets, and higher levels completely blocked lipid production. Our results establish that lipoxygenase-derived oxylipins produced from 18-carbon PUFA differentially affect multiple adipocyte processes associated with lipid storage and adipokine production. However, these effects are not due to the oxylipins blocking adipocyte maturation and thus globally suppressing all adipocyte characteristics. Furthermore, these oxylipin species decrease the lipid content of adipocytes regardless from which precursor fatty acid or lipoxygenase they were derived. Consequently, adipocyte characteristics can be altered through the ability of oxylipins to selectively modulate levels of proteins involved in both lipid metabolism and adipokine production.

Treating inflammation and infection in the 21st century: new hints from decoding resolution mediators and mechanisms

Practitioners of ancient societies from the time of Hippocrates and earlier recognized and treated the signs of inflammation, heat, redness, swelling, and pain with agents that block or inhibit proinflammatory chemical mediators. More selective drugs are available today, but this therapeutic concept has not changed. Because the acute inflammatory response is host protective to contain foreign invaders, much of today's pharmacopeia can cause serious unwanted side effects, such as immune suppression. Uncontrolled inflammation is now considered pathophysiologic and is associated with many widely occurring diseases such as cardiovascular disease, neurodegenerative diseases, diabetes, obesity, and asthma, as well as classic inflammatory diseases (e.g., arthritis and periodontal diseases). The inflammatory response, when self-limited, produces a superfamily of chemical mediators that stimulate resolution of the response. Specialized proresolving mediators (SPMs), identified in recent years, are endogenous mediators that include the n-3-derived families resolvins, protectins, and maresins, as well as arachidonic acid-derived (n-6) lipoxins, which promote resolution of inflammation, clearance of microbes, reduction of pain, and promotion of tissue regeneration via novel mechanisms. Aspirin and statins have a positive impact on these resolution pathways, producing epimeric forms of specific SPMs, whereas other drugs can disrupt timely resolution. In this article, evidence from recent human and preclinical animal studies is reviewed, indicating that SPMs are physiologic mediators and pharmacologic agonists that stimulate resolution of inflammation and infection. The findings suggest that it is time to challenge current treatment practices-namely, using inhibitors and antagonists alone-and to develop immunoresolvents as agonists to test resolution pharmacology and their role in catabasis for their therapeutic potential.-Serhan, C. N. Treating inflammation and infection in the 21st century: new hints from decoding resolution mediators and mechanisms.

Maresin 1 Mitigates High Glucose-Induced Mouse Glomerular Mesangial Cell Injury by Inhibiting Inflammation and Fibrosis

Background. Inflammation and fibrosis are the important pathophysiologic processes in diabetic nephropathy (DN). Maresin 1 is a potential anti-inflammatory lipid mediator, which has displayed powerful proresolving activities. Aim. We determine whether maresin 1 has protective effect on mouse glomerular mesangial cells (GMCs) induced by high glucose. Methods. We cultured GMCs stimulated by high glucose and categorized as follows: normal glucose group (5.6 mmol/L), high glucose group (30 mmol/L), mannitol group, maresin 1 intervention group (1, 10, and 100 nmol/L), maresin 1 and normal glucose group, and the N-acetylcysteine (NAC) intervention group (10 μmol/L NAC). After 24 h, the expression of ROS, NLRP3, caspase-1, procaspase-1, IL-1β, and pro-IL-1β was detected by western-blot, RT-PCR, and immunofluorescence. After 48 h, the expression of TGF-β1 and FN was detected by RT-PCR and ELISA. Results. Compared with normal glucose group, the expression of ROS, NLRP3, caspase-1, IL-1β, TGF-β1, and FN increased in high glucose group (P < 0.05), but it decreased after the treatment of maresin 1 in different concentrations. On the contrary, the expression of procaspase-1 and pro-IL-1β protein was restrained by high glucose and enhanced by maresin 1 in a dose-dependent manner (P < 0.05). Conclusion. Maresin 1 can inhibit NLRP3 inflammasome, TGF-β1, and FN in GMCs; it may have protective effect on DN by mitigating the inflammation and early fibrosis.

Extracted Triterpenes from Antrodia cinnamomea Reduce the Inflammation to Promote the Wound Healing via the STZ Inducing Hyperglycemia-Diabetes Mice Model

This research evaluated the effects of triterpenes on the regulation of STZ-induced hyperglycaemic diabetes through an anti-inflammatory response. Diabetic mice were orally administered various concentrations of triterpenes on a daily basis. Weight gain, volume of drinking water, and liver and spleen weight were recorded and evaluated. These evaluations presented a positive regulation to the abnormal metabolism appearance compared to the diabetic mice. In the diabetic mice, the detection of adiponectin production or elevated levels of inflammatory factors such as CCL1 and TPO expression were found to reduce hyperglycaemia and thereby induce an inflammatory response. Moreover, to the best of our knowledge, hyperglycaemia impairs the tissue healing associated with an increased and prolonged inflammatory response. An investigation of the anti-inflammatory response in wound healing as affected by the triterpenes verified the promotion of wound recovery.

Diabetes mellitus: The linkage between oxidative stress, inflammation, hypercoagulability and vascular complications

BACKGROUND

Vascular complications are the leading cause of morbidity and mortality among patients with type 1 and type 2 diabetes mellitus. These vascular abnormalities result of a chronic hyperglycemic state, which leads to an increase in oxidative stress and inflammatory responses.

AIM

This review addresses the relationships among endothelial dysfunction, hypercoagulability and inflammation and their biomarkers in the development of vascular complications in type 1 and type 2 diabetes.

RESULTS

Inflammation, endothelial dysfunction, and hypercoagulability are correlated to each other, playing an important role in the development of vascular complications in diabetic patients. Moreover, it has been observed that several endothelial, inflammatory and pro-coagulant biomarkers, such as VWF, IL-6, TNF-α, D-dimer and PAI-1, are increased in diabetic patients who have microvascular and macrovascular complications, including nephropathy or cardiovascular disease.

CONCLUSION

It is promising the clinical and laboratory use of endothelial, inflammatory and pro-coagulant biomarkers for predicting the risk of cardiovascular and renal complications in diabetic patients and for monitoring these patients.

Impact of anti-inflammatory nutrients on obesity-associated metabolic-inflammation from childhood through to adulthood

Obesity-related metabolic conditions such as insulin resistance (IR), type 2 diabetes and CVD share a number of pathological features, one of which is metabolic-inflammation. Metabolic-inflammation results from the infiltration of immune cells into the adipose tissue, driving a pro-inflammatory environment, which can induce IR. Furthermore, resolution of inflammation, an active process wherein the immune system counteracts pro-inflammatory states, may be dysregulated in obesity. Anti-inflammatory nutritional interventions have focused on attenuating this pro-inflammatory environment. Furthermore, with inherent variability among individuals, establishing at-risk populations who respond favourably to nutritional intervention strategies is important. This review will focus on chronic low-grade metabolic-inflammation, resolution of inflammation and the putative role anti-inflammatory nutrients have as a potential therapy. Finally, in the context of personalised nutrition, the approaches used in defining individuals who respond favourably to nutritional interventions will be highlighted. With increasing prevalence of obesity in younger people, age-dependent biological processes, preventative strategies and therapeutic options are important to help protect against development of obesity-associated co-morbidities.

Therapeutic Targets for Management of Periodontitis and Diabetes

The increasing incidence of diabetes mellitus (DM) and chronic periodontitis (CP) worldwide imposes a rethinking of individualized therapy for patients with both conditions. Central to bidirectional links between DM and CP is deregulated systemic inflammation and dysfunctional immune responses to altered-self and non-self. Control of blood glucose levels and metabolic imbalances associated with hyperglycemia in DM, and disruption of pathogenic subgingival biofilms in CP are currently the main therapeutic approaches for these conditions. Mounting evidence suggests the need to integrate immune modulatory therapeutics in treatment regimens that address the unresolved inflammation associated with DM and CP. The current review discusses the pathogenesis of DM and CP with emphasis on deregulated inflammation, current therapeutic approaches and the novel pro-resolution lipid mediators derived from Ω-3 polyunsaturated fatty acids.

Lipoxin A4 Attenuates Obesity-Induced Adipose Inflammation and Associated Liver and Kidney Disease

The role of inflammation in obesity-related pathologies is well established. We investigated the therapeutic potential of LipoxinA4 (LXA4:5(S),6(R),15(S)-trihydroxy-7E,9E,11Z,13E,-eicosatetraenoic acid) and a synthetic 15(R)-Benzo-LXA4-analog as interventions in a 3-month high-fat diet (HFD; 60% fat)-induced obesity model. Obesity caused distinct pathologies, including impaired glucose tolerance, adipose inflammation, fatty liver, and chronic kidney disease (CKD). Lipoxins (LXs) attenuated obesity-induced CKD, reducing glomerular expansion, mesangial matrix, and urinary H2O2. Furthermore, LXA4 reduced liver weight, serum alanine-aminotransferase, and hepatic triglycerides. LXA4 decreased obesity-induced adipose inflammation, attenuating TNF-α and CD11c(+) M1-macrophages (MΦs), while restoring CD206(+) M2-MΦs and increasing Annexin-A1. LXs did not affect renal or hepatic MΦs, suggesting protection occurred via attenuation of adipose inflammation. LXs restored adipose expression of autophagy markers LC3-II and p62. LX-mediated protection was demonstrable in adiponectin(-/-) mice, suggesting that the mechanism was adiponectin independent. In conclusion, LXs protect against obesity-induced systemic disease, and these data support a novel therapeutic paradigm for treating obesity and associated pathologies.

Tumor necrosis factor alpha -238 G/A and -308 G/A polymorphisms and soluble TNF-α levels in chronic kidney disease: correlation with clinical variables

Chronic kidney disease (CKD) is characterized by accumulation of proinflammatory cytokines, mainly tumor necrosis factor alpha (TNF-α). Single nucleotide polymorphisms (SNPs) of TNFA gene, including -238 G/A and -308 G/A, have been associated with alteration in the soluble TNF-α (sTNF-α) expression. The aim was to investigate the association of -238 y -308 TNFA gene SNPs with sTNF-α levels in CKD patients. We included 150 CKD patients and 192 control subjects (CS). Both SNPs were genotyped with polymerase chain reaction-restriction fragment length polymorphism technique and sTNF-α levels were measured by enzyme-linked immunosorbent assay. The genotypic distribution of -238 and -308 SNPs was not significantly different between CKD patients and CS (p > 0.001). However, the sTNF-α levels were higher in CKD, compared to CS (p < 0.001). Also, sTNF-α correlated with creatinine (r = 0.279, p = 0.004), urea (r = 0.325, p = 0.001), phosphorus (r = 0.479, p = 0.001), glomerular filtration rate (r = -0.236, p = 0.019) and monocyte count (r = 0.276, p = 0.010). In conclusion, elevated sTNF-α levels are associated with CKD. However, the -238 and -308 TNFA gene SNPs were not associated with susceptibility to CKD and sTNF-α levels in a Mexican population.

Association of red blood cell n-3 polyunsaturated fatty acids with plasma inflammatory biomarkers among the Quebec Cree population

BACKGROUND/OBJECTIVES

We examined the prevalence of elevated plasma high-sensitivity C-reactive protein (hs-CRP) concentrations and associations with red blood cell (RBC) long-chain n-3 polyunsaturated fatty acids (LCn-3PUFA) in the James Bay Cree population from the province of Quebec (Canada).

SUBJECTS/METHODS

A total of 744 Cree adults (18-91 years) from seven communities of Eastern James Bay were included in these cross-sectional analyses. Associations between RBC LCn-3PUFA and proinflammatory markers (hs-CRP, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α)) were assessed by using multivariate general linear models with adjustment for sex, age and waist circumference. An arbitrary inflammation score was defined based on the sum of the quartiles of hs-CRP, IL-6 and TNF-α concentrations (range=3-12).

RESULTS

Elevated hs-CRP concentrations (>3 mg/l) were present in 46.9% (95% confidence interval (CI) 43.3-50.5) of the James Bay Cree population. RBC docosapentaenoic acid (DPAn-3; C22:5n-3) was inversely associated with hs-CRP, TNF-α and the inflammation score (all P trend<0.02), whereas eicosapentaenoic acid (C20:5n-3) and docosahexaenoic acid (C22:6n-3) in RBC were not associated with inflammation (all P trend>0.18). Among participants with RBC DPAn-3 levels above the median of the population, odds ratio of having an elevated inflammation score (≥9) was 0.67 (95% CI, 0.48-0.93) compared with participants below the median.

CONCLUSIONS

RESULTS indicate that low-grade systemic inflammation is highly prevalent and that higher RBC DPAn-3 levels are associated with a lower risk of systemic inflammation in the James Bay Cree population.

Effects of platycodins on liver complications of type 2 diabetes

The aim of the current study was to investigate the therapeutic effects and mechanism of platycodin in liver complications of type 2 diabetes. All rats were randomly divided into two groups: The control group (normal diet) and the model group (a high‑fat and high‑sugar diet). The model group was injected with 2% streptozocin (25 mg/kg body weight) through the tail vein following 4 weeks of dieting. After a total of 8 weeks of dieting, fasting blood glucose (FBG) and liver function were examined. The high‑fat and high‑sugar diet was continued in the successful model rats, which were randomly divided into four groups and treated with the following doses of platycodins: The untreated, and 50, 100 and 200 mg/kg body weight/day groups. Platycodins treatment lasted for 12 weeks. Platycodins treatment at a dose of 200 mg/kg body weight/day reduced the FBG, glutamate pyruvate transaminase (GPT), glutamic oxalacetic transaminase, triglycerides, total cholesterol (TC), low‑density lipoprotein (LDL) and liver index levels compared with the untreated group (P<0.05), while the high‑density lipoprotein levels increased (P<0.05). Furthermore, FBG, GPT, TC and LDL levels were returned to the normal level. This dose also increased the expression of BMP‑9 mRNA and BMP‑9 protein, and reduced the expression of Smad‑4 mRNA and Smad‑4 protein. These findings indicate that platycodins can rectify disorders of blood glucose and lipid metabolism, improve liver index and protect liver function in liver complications of type 2 diabetes. The current study suggests that this therapeutic effect is mediated through the BMP‑9/Smad‑4 pathway.

Identification and signature profiles for pro-resolving and inflammatory lipid mediators in human tissue

Resolution of acute inflammation is an active process locally controlled by a novel genus of specialized pro-resolving mediators (SPM) that orchestrate key resolution responses. Hence, it is of general interest to identify individual bioactive mediators and profile their biosynthetic pathways with related isomers as well as their relation(s) to classic eicosanoids in mammalian tissues. Lipid mediator (LM)-SPM levels and signature profiles of their biosynthetic pathways were investigated using liquid chromatography-tandem mass spectrometry (LC-MS-MS)-based LM metabololipidomics. LM and SPM were identified using ≥6 diagnostic ions and chromatographic behavior matching with both authentic and synthetic materials. This approach was validated using the composite reference plasma (SRM1950) of 100 healthy individuals. Using targeted LM metabololipidomics, we profiled LM and SPM pathways in human peripheral blood (plasma and serum) and lymphoid organs. In these, we identified endogenous SPM metabolomes, namely, the potent lipoxins (LX), resolvins (Rv), protectins (PD), and maresins (MaR). These included RvD1, RvD2, RvD3, MaR1, and NPD1/PD1, which were identified in amounts within their bioactive ranges. In plasma and serum, principal component analysis (PCA) identified signature profiles of eicosanoids and SPM clusters. Plasma-SPM increased with omega-3 and acetylsalicylic acid intake that correlated with increased phagocytosis of Escherichia coli in whole blood. These findings demonstrate an approach for identification of SPM pathways (e.g., resolvins, protectins, and maresins) in human blood and lymphoid tissues that were in amounts commensurate with their pro-resolving, organ protective, and tissue regeneration functions. LM metabololipidomics coupled with calibration tissues and physiological changes documented herein provide a tool for functional phenotypic profiling.

LC-MS/MS analysis of plasma polyunsaturated fatty acids in type 2 diabetic patients after insulin analog initiation therapy

Background

Eicosanoids derived from omega-6 (n6) polyunsaturated fatty acids (PUFAs) have proinflammatory functions whereas eicosanoids derived from omega-3 (n3) PUFAs have anti-inflammatory properties. This study was designed to evaluate the effect of insulin analog initiation therapy on n6 and n3 PUFAs in type 2 diabetic patients during early phase.

Methods

Sixteen type 2 diabetic patients with glycosylated hemoglobin (HbA1c) levels above 10% despite ongoing combination therapy with sulphonylurea and metformin were selected. Former treatment regimen was continued for the first day followed by substitution of sulphonylurea therapy with different insulin analogs (0.4 U/kg/day) plus metformin. Blood samples were obtained from all patients at 24 and 72 hours. Plasma levels of arachidonic acid (AA, C20:4n6), dihomo-gamma-linolenic acid (DGLA, C20:3n6), eicosapentaenoic acid (EPA, C20:5n3) and docosahexaenoic acid (DHA, C22:6n3) were determined by an optimized multiple reaction monitoring (MRM) method using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Prostaglandin E₂ (PGE2) was measured in serum samples by enzyme immunoassay.

Results

All measured PUFAs were significantly increased after treatment with insulin analogs plus metformin compared to before treatment levels. The mean AA/EPA ratio was significantly lower after treatment with insulin analogs plus metformin. A 22% decrease was observed in PGE2 levels after treatment with insulin analogs plus metformin compared to pretreatment levels (p > 0.05).

Conclusion

The significant decrease in AA/EPA ratio indicates that insulin analog initiation therapy has anti-inflammatory properties by favoring the increase of n3 fatty acid EPA.

Elevated toll-like receptor 3 inhibits pancreatic β-cell proliferation through G1 phase cell cycle arrest

Activation of the innate and acquired immune systems plays an important role in chronic inflammatory diseases and conditions such as obesity, insulin resistance, type 2 diabetes mellitus and atherosclerosis, with additional roles in regulation of cell proliferation and survival. Here, we provide evidence that TLR3 can respond to nutrient signals and induce loss of β-cell mass through induction of G1 cycle arrest. Activation of TLR3 by polyinosinic-polycytidylic acid [poly (I:C)] was shown to trigger the decline of cyclin D1/2 protein levels in pancreatic β-cell lines, which could be reversed by the proteasome inhibitor MG132. P38 was also found to interfere with this degradation which may be associated with G1 cycle arrest. Moreover, inhibitory effects of TLR3 on β-cell growth were supported by gene silencing of TRIF, which could inhibit p38 activity in response to poly (I:C) stimuli. These results support a role for TLR3 in β-cell mass loss in metabolic surplus and raise the possibility that TRIF/p38 signaling may be involved in G1 phase cycle arrest through ubiquitin/proteasome-dependent degradation of cyclin D.

Obesity, immunomodulation and chronic kidney disease

Obesity-induced inflammation is associated with numerous pathologies and is an independent risk factor of chronic kidney disease (CKD). The prevalence of CKD is escalating and current therapeutic strategies are seriously lacking in efficacy, and immunomodulation has been suggested as a potential new therapeutic approach. Indeed, specialized pro-resolving mediators (SPMs), such as lipoxins (LXs), resolvins and protectins, have demonstrated protection in adipose inflammation, restoring insulin sensitivity and adiponectin production, while modulating leukocyte infiltration and promoting resolution in visceral adipose tissue. Furthermore, SPMs display direct renoprotective effect. Thus we review current evidence of immunomodulation as a potential strategy to subvert obesity-related CKD.