Regulation of energy metabolism by inflammation: a feedback response in obesity and calorie restriction

Focusing on post-COVID syndrome fatigue

INTRODUCTION

More than 100 million people worldwide have been infected by SARS-CoV-2 virus, the virus responsible for the acute disease COVID-19. Multiple studies have shown how various symptoms in these patients can persist for several months after resolution of the acute process, a phenomenon known as post-COVID syndrome. Neurological symptoms are varied, but the great majority of patients present fatigue.

OBJECTIVE

To analyse post-COVID fatigue.

METHODS

We present a prospective, single-centre, case-control study comparing patients with fatigue in the context of post-COVID syndrome with patients with history of COVID-19 but without post-COVID fatigue. Data were recorded at baseline (April 2021) and at 6 months. Data were recorded on clinical variables, fatigue questionnaires, sleep disorders, depression, anxiety, cognitive impairment, and quality of life. Basic laboratory analysis was performed with blood samples collected at the 2 visits. In addition, a substudy of proinflammatory (IL-6, IL-1β, TNF-α) and anti-inflammatory (IL-10) cytokines was performed.

RESULTS

Fatigue as measured by the Chalder Fatigue Scale was mixed (physical and psychological) and of moderate intensity. At 6 months, physical fatigue improved, but psychological fatigue did not. Significant differences were found in sleepiness, cognitive impairment, anxiety, and quality of life. Significant alterations were observed in TNF-α levels, but not in the remaining cytokines.

CONCLUSIONS

Patients with fatigue presented a poorer quality of life, with an improvement being observed at 6 months, which suggests a course that may be self-limiting; however, this will have to be confirmed with longer studies.

Modulation of GABAergic system as a therapeutic option in stroke

Stroke is one of the leading causes of death and permanent adult disability worldwide. Despite the improvements in reducing the rate and mortality, the societal burden and costs of treatment associated with stroke management are increasing. Most of the therapeutic approaches directly targeting ischemic injury have failed to reduce short- and long-term morbidity and mortality and more effective therapeutic strategies are still needed to promote post-stroke functional recovery. Decades of stroke research have been focused on hyperexcitability and glutamate-induced excitotoxicity in the acute phase of ischemia and their relation to motor deficits. Recent advances in understanding the pathophysiology of stroke have been made with several lines of evidence suggesting that changes in the neurotransmission of the major inhibitory system via γ-Aminobutyric acid (GABA) play a particularly important role in functional recovery and deserve further attention. The present review provides an overview of how GABAergic neurotransmission changes correlate with stroke recovery and outlines GABAergic system modulators with special emphasis on neurosteroids that have been shown to affect stroke pathogenesis or plasticity or to protect against cognitive decline. Supporting evidence from both animal and human clinical studies is presented and the potential for GABA signaling-targeted therapies for stroke is discussed to translate this concept to human neural repair therapies. Age and sex are considered crucial parameters related to the pathophysiology of stroke and important factors in the development of therapeutic pharmacological strategies. Future work is needed to deepen our knowledge of the neurochemical changes after stroke, extend the conceptual framework, and allow for the development of more effective interventions that include the modulation of the inhibitory system.

Energy restriction inhibits β-catenin ubiquitination to improve ischemic stroke injury via USP18/SKP2 axis

Ischemic stroke (IS) remains a global health issue because of its great disability and mortality. Energy restriction (ER) has been justified to perform an inhibitory role in cerebral injury caused by IS. This research was purposed to inquire the potential molecular mechanism of ER in IS. To verify the function of ER in the animal and cell models of IS, rats were subjected to intermittent fasting (IF) and middle cerebral artery occlusion/reperfusion (MCAO/R) surgery and HAPI cells were treated with oxygen-glucose deprivation and reoxygenation (OGD/R) and 2-deoxyglucose (2-DG). It was disclosed that IF mitigated brain damage and inflammation in MCAO/R rats. Likewise, ER inhibited OGD/R-evoked microglial activation and inflammatory response. Of note, ubiquitin specific protease 18 (USP18) was uncovered to be the most significantly upregulated in MCAO/R rats receiving IF compared to free-feeding MCAO/R rats. Real-time quantitative polymerase chain reaction (RT-qPCR) and western blot verified that ER led to the promotion of USP18 expression. Moreover, downregulation of USP18 neutralized the meliorative effects of ER on OGD/R-treated HAPI cells. Functionally, USP18 restrained β-catenin ubiquitination to enhance its expression. In addition, our results manifested that S-phase kinase associated protein 2 (SKP2) contributed to degradation of β-catenin and USP18 abolished the role of SKP2 in β-catenin ubiquitination. Knockout of USP18 eliminated the protective effects of IF on MCAO/R rats, while SKP2 exacerbated brain damage and inflammation by decreasing β-catenin expression after IF. In summary, we validated that ER-induced USP18 exerts a suppressive function in IS damage through SKP2-mediated β-catenin ubiquitination.

Unravelling bisphenol A-induced hepatotoxicity: Insights into oxidative stress, inflammation, and energy dysregulation

Bisphenol A (BPA), a prevalent plastic monomer and endocrine disruptor, negatively impacts metabolic functions. This study examines the chronic effects of eco-relevant BPA concentrations on hepatotoxicity, focusing on redox balance, inflammatory response, cellular energy sensors, and metabolic homeostasis in male Swiss albino mice. Chronic BPA exposure resulted in reactive oxygen species (ROS) accumulation, altered hepatic antioxidant defense, lipid peroxidation, and NOX4 expression, leading to reduced cell viability. Additionally, BPA exposure significantly upregulated hepatic pro-inflammatory cytokine genes (Tnf-α, Il-1β, Il-6), NOS2, and arginase II, correlating with increased TLR4 expression, NF-κB phosphorylation, and a dose-dependent decrease in IκBα levels. BPA-induced NF-κB nuclear localization and inflammasome activation (NLRP3, cleaved caspase-1, IL-1β) established an inflammatory milieu. Perturbations in hepatic AMPKα phosphorylation, SIRT1, and PGC-1α, along with elevated p38 MAPK phosphorylation and ERα expression, indicated BPA-induced energy dysregulation. Furthermore, increased PLA2G4A, COX1, COX2, and PTGES2 expression in BPA-treated liver correlated with hyperlipidemia, hepatic FASN expression, steatosis, and visceral adiposity, likely due to disrupted energy sensors, oxidative stress, and inflammasome activation. Elevated liver enzymes (ALP, AST, ALT) and apoptotic markers indicated liver damage. Notably, N-acetylcysteine (NAC) priming reversed BPA-induced hepatocellular ROS accumulation, NF-κB-inflammasome activation, and intracellular lipid accumulation, while upregulating cellular energy sensors and attenuating ERα expression, suggesting NAC's protective effects against BPA-induced hepatotoxicity. Pharmacological inhibition of the NF-κB/NLRP3 cascade in BAY11-7082 pretreated, or NLRP3 immunodepleted hepatocytes reversed BPA's negative impact on SIRT1/p-AMPKα/PGC-1α and intracellular lipid accumulation, providing mechanistic insights into BPA-induced metabolic disruption.

Acylation stimulating protein/C3adesArg in the metabolic states: role of adipocyte dysfunction in obesity complications

Adipose tissue, as an endocrine organ, secretes several adipocyte-derived hormones named 'adipokines' that are implicated in regulating energy haemostasis. Substantial evidence shows that white adipose tissue-derived adipokines mediate the link between obesity-related exogenous factors (like diet and lifestyle) and various biological events (such as pre- and postmenopausal status) that have obesity consequences (cardiometabolic disorders). One of the critical aetiological factors for obesity-related diseases is the dysfunction of adipokine pathways. Acylation-stimulating protein (ASP) is an adipokine that stimulates triglyceride synthesis and storage in adipose tissue by enhancing glucose and fatty acid uptake. ASP acts via its receptor C5L2. The primary objective of this review is to address the existing gap in the literature regarding ASP by investigating its diverse responses and receptor interactions across multiple determinants of obesity. These determinants include diet composition, metabolic disorders, organ involvement, sex and sex hormone levels. Furthermore, this article explores the broader paradigm shift from solely focusing on adipose tissue mass, which contributes to obesity, to considering the broader implications of adipose tissue function. Additionally, we raise a critical question concerning the clinical relevance of the insights gained from this review, both in terms of potential therapeutic interventions targeting ASP and in the context of preventing obesity-related conditions, highlighting the potential of the ASP-C5L2 interaction as a pharmacological target. In conclusion, these findings validate that obesity is a low-grade inflammatory status with multiorgan involvement and sex differences, demonstrating dynamic interactions between immune and metabolic response determinants.

Nonlinear Relationship Between Systemic Immune-Inflammation and Hepatic Steatosis: A Population-Based Study in China

Background

Studies on the associations between Systemic Immune-Inflammation (SII) and hepatic steatosis in China are still lacking. It is necessary to clarify the relationship between SII and hepatic steatosis in the Chinese population.

Methods

This study was conducted from January 2022 to December 2022. A total of 37,095 participants were enrolled, among them, with 20,709 (55.83%) being males, and 16,386 (44.17%) being females. Physical and biochemical indicators were measured during a morning health examination after the examinees had fasted overnight. Diagnoses of hepatic steatosis were determined using an ultrasound test in accordance with the Chinese Guideline. Analysis of variance and chi-square tests were used to analyze the association between SII and hepatic steatosis. Stratification analyses were conducted based on age, gender, and obese status. Restricted cubic spline regression was also performed to explore the shapes of associations between SII and hepatic steatosis.

Results

The average age of the 37,095 participants was 44.78 years old, with those with hepatic steatosis (11,599 (31.27%)) averaging 47.06 years old and those (25,496 (68.73%)) in the control group averaging 43.73 years old. SII was positively associated with hepatic steatosis. This association remained significant after conducting stratification analysis by age and gender. The inflection points in the inverted U-shaped curve for the relationship between SII and hepatic steatosis were 399.78 for gender (1000 cells /µL)(nonlinear P<0.01, OR=1.31 (male), 1.00 (female)) and 385.79 for age (1000 cells /µL)(nonlinear P<0.01, OR=1.35 (18~44 years old), 1.87 (45~59 years old), 1.93 (60~ years old)).

Conclusion

SII is an independent risk factor for hepatic steatosis, and this effect appears to be stronger in subjects with BMI <28 kg/m2. The nonlinear relationship between SII and hepatic steatosis, characterized by an inverted U-shaped distribution, may serve as a reference for diagnosing and evaluating hepatic steatosis.

A pathological convergence theory for non-communicable diseases

The current paradigm considers the study of non-communicable diseases (NCDs), which are the main causes of mortality, as individual disorders. Nevertheless, this conception is being solidly challenged by numerous remarkable studies. The clear fact that the mortality, by virtually all NCDs, tends to cluster at old ages (with the exception of congenital malformations and certain types of cancer, among a few others); makes us intuitive to assume that the common convergence mechanism that exponentially increases mortality by almost all NCDs in older ages is cell aging. Moreover, when we study NCDs, we are not analyzing which disorders cause the mortality of the populations, rather that which disorders kill us before others do, because the aging of the individuals causes inevitably their death by one cause or another. This is not a defeatist perspective, but a challenging and efficient one. These intuitive assumptions have been supported by studies from the pathophysiologic, epidemiologic, and genetic fields, leading to the affirmation that, as NCDs share genetic and pathophysiological mechanisms (derived from mostly the same risk factors), they should no longer be considered independently. Those studies should make us reconsider our current conceptions of studying NCDs as individual disorders, and to hypothesize about a paradigm that would consider most NCDs (cancer, neurological pathologies, cardiovascular diseases, type II diabetes mellitus, chronic respiratory diseases, osteoarthritis, and osteoporosis, among others) different manifestations of the same process: the cell aging.

Cardioprotective effects of calorie restriction against inflammation and apoptosis in ovariectomized obese rats: Role of classical estrogen receptors and SIRT1

AIM

Obesity is a metabolic complication linked with bad eating habits and a sedentary lifestyle, and the heart is one of the target organs damaged by it. Estrogen deficiency during menopause worsens the situation. Calorie restriction (CR) can contribute to reducing cardiovascular disease (CVD) in postmenopausal conditions. Thus, the effects of CR on inflammation and apoptosis in ovariectomized rats' hearts with obesity were studied.

METHOD

Female Wistar rats were categorized into Sham and OVX (ovariectomized) groups and received a standard diet (SD) or high-fat diet (60%HFD) or calorie restriction (30% CR) for 16 weeks. The real-time PCR method was used to evaluate the inflammatory markers and estrogen receptors gene expression. Western-blot and ELISA methods were respectively used for the measurement of apoptosis and SIRT1 protein expression.

RESULTS

HFD led to the elevation of body weight, IL-6 (interleukin-6) and TNF-α (tumor necrosis factor-α) and reduction of IL-10 (interleukin-10) gene expressions, and also an increment in protein levels of cleaved caspase-3, Bax and Bax/Bcl2 ratio and decrement in Bcl-2 in OVX rats (P < 0.001). Additionally, HFD reduced SIRT1 (sirtuin1) protein levels, ERα (estrogen receptor α), and ERβ (estrogen receptor β) gene expressions (P < 0.001). In contrast, CR declined body weight, IL-6 and TNF-α (P < 0.001), increased IL-10 expressions (P < 0.05), decreased cleaved caspase-3 (P < 0.001), Bax (P < 0.01), and Bax/Bcl2 ratio (P < 0.05), enhanced Bcl-2 (P < 0.001), increased SIRT1 (P < 0.05) and ERα (P < 0.001) and ERβ (P < 0.01) expressions.

CONCLUSION

CR through the SIRT1 regulation and estrogen receptors attenuate obesity-induced-cardiac inflammation and apoptosis. CR can be a cardioprotective candidate in postmenopausal conditions.

Obesity phenotypes and cardiovascular risk: From pathophysiology to clinical management

Obesity epidemic reached the dimensions of a real global health crisis with more than one billion people worldwide living with obesity. Multiple obesity-related mechanisms cause structural, functional, humoral, and hemodynamic alterations with cardiovascular (CV) deleterious effects. A correct assessment of the cardiovascular risk in people with obesity is critical for reducing mortality and preserving quality of life. The correct identification of the obesity status remains difficult as recent evidence suggest that different phenotypes of obesity exist, each one associated with different degrees of CV risk. Diagnosis of obesity cannot depend only on anthropometric parameters but should include a precise assessment of the metabolic status. Recently, the World Heart Federation and World Obesity Federation provided an action plan for management of obesity-related CV risk and mortality, stressing for the instauration of comprehensive structured programs encompassing multidisciplinary teams. In this review we aim at providing an updated summary regarding the different obesity phenotypes, their specific effects on CV risk and differences in clinical management.

Extracts of Dunkelfelder Grape Seeds and Peel Increase the Metabolic Rate and Reduce Fat Deposition in Mice Maintained on a High-Fat Diet

Chronic high-fat diet intake may induce obesity and increase the risk of metabolic syndrome. The pomace of grape (Vitis vinifera L.) is rich in polyphenols, which are candidates for anti-obesity therapy. The present study aimed to investigate the effects of Dunkelfelder grape seed extract (GSE) and grape peel extract (GPE) on lipid and energy metabolism disorders in mice maintained on a high-fat diet (HFD). Male nine-week C57BL/6J mice were randomly assigned to one of four groups, namely, the normal chow diet (ND), HFD, HFD plus GSE (400 mg/kg BW) administered by oral gavage, or HFD plus GPE (400 mg/kg BW) administered by oral gavage. There were eight mice per group, and the experiment was 14 weeks in duration. The results showed that GSE and GPE treatments did not affect energy intake in mice on a high-fat diet, but body weight gain was 24.5% and 17.3% lower in the GSE- and GPE-treated mice than in the HFD group, respectively. They also decreased blood triglyceride (TG), total cholesterol (TC), and fasting blood glucose levels and increased high-density lipoprotein cholesterol (HDL-C). In addition, GSE and GPE reduced adipose tissue weight and excessive lipid droplet accumulation in the adipocytes. The metabolic chamber test showed that the GSE and GPE treatments enhanced oxygen consumption, carbon dioxide production, and heat release while decreasing the respiratory exchange rate (RER). This suggests that GSE and GPE augmented fuel oxidation and energy generation and increased the proportion of lipids being utilized in energy metabolism. GSE and GPE also upregulated the genes controlling lipolysis and downregulated those controlling lipogenesis in adipose tissues. Moreover, they significantly increased the expression levels of the genes regulating thermogenesis in BAT, eWAT, and iWAT, and mitochondrial biogenesis in all three types of adipose tissue. In conclusion, the present study empirically demonstrated that GSE and GPE enhance body fat utilization by augmenting lipid and energy metabolism and could, therefore, ameliorate high-fat diet-induced obesity.

The reverse transcriptase inhibitor 3TC protects against age-related cognitive dysfunction

Aging is the primary risk factor for most neurodegenerative diseases, including Alzheimer's disease. Major hallmarks of brain aging include neuroinflammation/immune activation and reduced neuronal health/function. These processes contribute to cognitive dysfunction (a key risk factor for Alzheimer's disease), but their upstream causes are incompletely understood. Age-related increases in transposable element (TE) transcripts might contribute to reduced cognitive function with brain aging, as the reverse transcriptase inhibitor 3TC reduces inflammation in peripheral tissues and TE transcripts have been linked with tau pathology in Alzheimer's disease. However, the effects of 3TC on cognitive function with aging have not been investigated. Here, in support of a role for TE transcripts in brain aging/cognitive decline, we show that 3TC: (a) improves cognitive function and reduces neuroinflammation in old wild-type mice; (b) preserves neuronal health with aging in mice and Caenorhabditis elegans; and (c) enhances cognitive function in a mouse model of tauopathy. We also provide insight on potential underlying mechanisms, as well as evidence of translational relevance for these observations by showing that TE transcripts accumulate with brain aging in humans, and that these age-related increases intersect with those observed in Alzheimer's disease. Collectively, our results suggest that TE transcript accumulation during aging may contribute to cognitive decline and neurodegeneration, and that targeting these events with reverse transcriptase inhibitors like 3TC could be a viable therapeutic strategy.

Inflammaging and Osteoarthritis

Osteoarthritis is a highly prevalent disease particularly in subjects over 65 years of age worldwide. While in the past it was considered a mere consequence of cartilage degradation leading to anatomical and functional joint impairment, in recent decades, there has been a more dynamic view with the synovium, the cartilage, and the subchondral bone producing inflammatory mediators which ultimately lead to cartilage damage. Inflammaging is defined as a chronic, sterile, low-grade inflammation state driven by endogenous signals in the absence of infections, occurring with aging. This chronic status is linked to the production of reactive oxygen species and molecules involved in the development of age-related disease such as cancer, diabetes, and cardiovascular and neurodegenerative diseases. Inflammaging contributes to osteoarthritis development where both the innate and the adaptive immune response are involved. Elevated systemic and local inflammatory cytokines and senescent molecules promote cartilage degradation, and antigens derived from damaged joints further trigger inflammation through inflammasome activation. B and T lymphocyte populations also change with inflammaging and OA, with reduced regulatory functions, thus implicating self-reactivity as an additional mechanism of joint damage. The discovery of the underlying pathogenic pathways may help to identify potential therapeutic targets for the management or the prevention of osteoarthritis. We will provide a comprehensive evaluation of the current literature on the role of inflammaging in osteoarthritis and discuss the emerging therapeutic strategies.

Ultrasound-Guided Interventions for Carpal Tunnel Syndrome: A Systematic Review and Meta-Analyses

Carpal tunnel syndrome (CTS) is the most common peripheral entrapment, and recently, ultrasound-guided perineural injection (UPIT) and percutaneous flexor retinaculum release (UPCTR) have been utilized to treat CTS. However, no systematic review or meta-analysis has included both intervention types of ultrasound-guided interventions for CTS. Therefore, we performed this review using four databases (i.e., PubMed, EMBASE, Scopus, and Cochrane) to evaluate the quality of evidence, effectiveness, and safety of the published studies on ultrasound-guided interventions in CTS. Among sixty studies selected for systemic review, 20 randomized treatment comparison or controlled studies were included in six meta-analyses. Steroid UPIT with ultrasound guidance outperformed that with landmark guidance. UPIT with higher-dose steroids outperformed that with lower-dose steroids. UPIT with 5% dextrose in water (D5W) outperformed control injection and hydrodissection with high-volume D5W was superior to that with low-volume D5W. UPIT with platelet-rich plasma outperformed various control treatments. UPCTR outperformed open surgery in terms of symptom improvement but not functional improvement. No serious adverse events were reported in the studies reviewed. The findings suggest that both UPIT and UPCTR may provide clinically important benefits and appear safe. Further treatment comparison studies are required to determine comparative therapeutic efficacy.

Beneficial Effects of Anti-Inflammatory Diet in Modulating Gut Microbiota and Controlling Obesity

Obesity has consistently been associated with an increased risk of metabolic abnormalities such as diabetes, hyperlipidemia, and cardiovascular diseases, as well as the development of several types of cancer. In recent decades, unfortunately, the rate of overweight/obesity has increased significantly among adults and children. A growing body of evidence shows that there is a relationship between metabolic disorders such as obesity and the composition of the gut microbiota. Additionally, inflammation is considered to be a driving force in the obesity-gut microbiota connection. Therefore, it seems that anti-inflammatory nutrients, foods, and/or diets can play an essential role in the management of obesity by affecting the intestinal flora and controlling inflammatory responses. In this review, we describe the links between the gut microbiota, obesity, and inflammation, and summarize the benefits of anti-inflammatory diets in preventing obesity.

Inflammaging is driven by upregulation of innate immune receptors and systemic interferon signaling and is ameliorated by dietary restriction

Aging is characterized by a chronic low-grade inflammation known as inflammaging in multiple tissues, representing a risk factor for age-related diseases. Dietary restriction (DR) is the best-known non-invasive method to ameliorate aging in many organisms. However, the molecular mechanism and the signaling pathways that drive inflammaging across different tissues and how they are modulated by DR are not yet understood. Here we identify a multi-tissue gene network regulating inflammaging. This network is characterized by chromatin opening and upregulation in the transcription of innate immune system receptors and by activation of interferon signaling through interferon regulatory factors, inflammatory cytokines, and Stat1-mediated transcription. DR ameliorates aging-induced alterations of chromatin accessibility and RNA transcription of the inflammaging gene network while failing to rescue those alterations on the rest of the genome. Our results present a comprehensive understanding of the molecular network regulating inflammation in aging and DR and provide anti-inflammaging therapeutic targets.

Ketogenic and Modified Mediterranean Diet as a Tool to Counteract Neuroinflammation in Multiple Sclerosis: Nutritional Suggestions

Ketogenic Diet is a nutritional pattern often used as dietotherapy in inflammatory diseases, including neurological disorders. Applied on epileptic children since 1920, in recent years it has been taken into account again as a tool to both reduce inflammatory burdens and ameliorate the nutritional status of patients affected by different pathologies. Multiple sclerosis (MS) is considered an immune-mediated neuro-inflammatory disease and diet is a possible factor in its pathogenesis. The aim of this work is to investigate the main potential targets of MS-related impairments, in particular the cognitive deficits, focusing on the alteration of biomarkers such as the Brain Derived-Neurotrophic Factor and the Tryptophan/Kynurenine ratio that could play a role on neuroprotection and thus on MS progression. Furthermore, we here propose nutritional suggestions which are useful in the development of a ketogenic diet protocol that takes advantage of the anti-inflammatory properties of low-carbohydrate foods from the Mediterranean diet to be applied to subjects with MS. In conclusion, this approach will allow one to develop the ketogenic diet combined with a modified Mediterranean diet as a possible tool to improve neuroinflammation in multiple sclerosis.

Mechanism of Glucose Water as a Neural Injection: A Perspective on Neuroinflammation

The entrapment of peripheral nerves is associated with chronic neuroinflammation and neuropathic pain, and perineural injection therapy with glucose is emerging as an effective treatment for peripheral entrapment neuropathy. However, the mechanism underlying the pharmacological effect of glucose on nerves remains unclear. One of the hypothesized mechanisms is that glucose reduces neurogenic inflammation. Therefore, we investigated the effects of high glucose concentrations on cytokine-induced neuroinflammation in vitro. Human SH-SY5Y neuronal cells were challenged with 10 ng/mL TNF-α for 16 h and subsequently treated with different glucose concentrations (0–25 mM) for 24 h. Cell viability was evaluated using the diphenyltetrazolium bromide assay, and proinflammatory cytokine levels were assessed using ELISA and quantitative PCR. In addition, mRNA levels of NF-κB and cyclooxygenase-2 were analyzed using quantitative PCR. Exposure to 10 ng/mL TNF-α resulted in decreased viability of SH-SY5Y cells and significant upregulation of IL-6, IL-1β, NF-κB, and cyclooxygenase-2. Subsequent exposure to high glucose levels (25 mM) markedly reduced the upregulation of IL-6, IL-1β, cyclooxygenase-2, and NF-κB, and restored the functional metabolism of SH-SY5Y cells, compared with that of the normal glucose control. Our findings suggest that high glucose concentrations can mitigate TNF-α-induced NF-κB activation, upregulation of proinflammatory cytokines, and metabolic dysfunction.

Immune and non-immune functions of adipose tissue leukocytes

Adipose tissue is a complex dynamic organ with whole-body immunometabolic influence. Much of the work into understanding the role of immune cells in adipose tissue has been in the context of obesity. These investigations have also uncovered a range of typical (immune) and non-typical functions exerted by adipose tissue leukocytes. Here we provide an overview of the adipose tissue immune system, including its role as an immune reservoir in the whole-body response to infection and as a site of parasitic and viral infections. We also describe the functional roles of specialized immunological structures found within adipose tissue. However, our main focus is on the recently discovered 'non-immune' functions of adipose tissue immune cells, which include the regulation of adipocyte homeostasis, as well as responses to changing nutrient status and body temperature. In doing so, we outline the therapeutic potential of the adipose tissue immune system in health and disease.

The transition between acute and chronic infections in light of energy control: a mathematical model of energy flow in response to infection

BACKGROUND

Different parts of an organism like the gut, endocrine, nervous and immune systems constantly exchange information. Understanding the pathogenesis of various systemic chronic diseases increasingly relies on understanding how these subsystems orchestrate their activities.

METHODS

We started from the working hypothesis that energy is a fundamental quantity that governs activity levels of all subsystems and that interactions between subsystems control the distribution of energy according to acute needs. Based on physiological knowledge, we constructed a mathematical model for the energy flow between subsystems and analysed the resulting organismal responses to in silico infections.

RESULTS

The model reproduces common behaviour in acute infections and suggests several host parameters that modulate infection duration and therapeutic responsiveness. Moreover, the model allows the formulation of conditions for the induction of chronic infections and predicts that alterations in energy released from fat can lead to the transition from clearance of acute infections to a chronic inflammatory state.

IMPACT

These results suggest a fundamental role for brain and fat in controlling immune response through systemic energy control. In particular, it suggests that lipolysis resistance, which is known to be involved in obesity and ageing, might be a survival programme for coping with chronic infections.

Lipidomics Revealed Aberrant Lipid Metabolism Caused by Inflammation in Cardiac Tissue in the Early Stage of Systemic Lupus Erythematosus in a Murine Model

Cardiac involvement, displayed as premature cardiovascular disease (CVD), is one of common clinical symptoms of patients with systemic lupus erythematosus (SLE), contributing to mortality of the disease. The precise underlying pathological mechanism(s) for the cardiac involvement in lupus remains poorly understood. Lipids and their metabolites are directly involved in atherosclerosis development, oxidative stress, and inflammation, which are closely related to the development of CVD. In the study, shotgun lipidomics was exploited to quantitatively analyze cellular lipidomes in the cardiac tissue of MRL/lpr mice at two different time points (i.e., pre-lupus and lupus state) with/without treatment with glucocorticoids (GCs). Urine protein, spleen index, and renal histopathological evaluation of the mice were also performed for assessment of SLE onset and/or outcome. Lipidomics analysis revealed that the deposition of cholesterol and the aberrant metabolism of lipids caused by the increased energy metabolism and the enhanced activation of phospholipases, both of which were originally induced by inflammation, were already present in cardiac tissues from lupus-prone mice even at pre-lupus state. These lipid alterations could further induce inflammation and autoimmune responses, accelerating the process of CVD. In addition, the present study also demonstrated that GCs therapy could not only delay the progression of SLE, but also partially corrected these alterations of lipid species in cardiac tissue due to their anti-inflammatory effect. Thus, the medications with better anti-inflammatory effect might be a useful therapeutic method for premature CVD of SLE.

Evaluation framework for systems models

As decisions in drug development increasingly rely on predictions from mechanistic systems models, assessing the predictive capability of such models is becoming more important. Several frameworks for the development of quantitative systems pharmacology (QSP) models have been proposed. In this paper, we add to this body of work with a framework that focuses on the appropriate use of qualitative and quantitative model evaluation methods. We provide details and references for those wishing to apply these methods, which include sensitivity and identifiability analyses, as well as concepts such as validation and uncertainty quantification. Many of these methods have been used successfully in other fields, but are not as common in QSP modeling. We illustrate how to apply these methods to evaluate QSP models, and propose methods to use in two case studies. We also share examples of misleading results when inappropriate analyses are used.

The effect of homocysteine on the expression of CD36, PPARγ, and C/EBPα in adipose tissue of normal and obese mice

The purpose of this study was to investigate the effect of homocysteine (Hcy) on CD36, PPARγ, and C/EBPα gene and protein expression in adipose tissue obtained from normal and high-calorie diet obesity models. CD36, PPARγ, and C/EBPα gene expression and protein levels in adipose tissue specimens were determined using the RT-PCR and ELISA methods, respectively. Significantly increased CD36 gene expression was observed in adipose tissue from obese mice, while Hcy significantly reduced CD36 gene expression in adipose tissue from normal and obese mice. PPARγ and C/EBPα gene expression levels decreased significantly in all groups compared to the normal group. In addition, levels of both PPARγ and C/EBPα gene expression were lower with Hcy supplementation compared to their own controls. In conclusion, Hcy's reduction of CD36 gene expression in adipose tissue may be one probable factor in hyperhomocysteinemia representing an independent risk factor for cardiovascular diseases.

Statistical Meta-Analysis of Risk Factors for Endometrial Cancer and Development of a Risk Prediction Model Using an Artificial Neural Network Algorithm

Simple Summary

A robust and comprehensive meta-analysis, for the first time, identified definitely that BMI is by far the most influential risk factor in endometrial cancer. Risk factors were previously only studied individually and or in smaller meta-analysis studies which grouped some factors together. BMI was shown to be an important risk factor with other factors less so, but no rank order was established. This work also offers, for the first time, a neural network computer model to predict the overall increase or decreased risk of cancer for individual patients, which is 98.6% accurate. This prediction can be used as a tool to determine if a patient should be considered for testing and to predict diagnosis, as well as to suggest prevention measures to patients.

Abstract

Objectives: In this study we wished to determine the rank order of risk factors for endometrial cancer and calculate a pooled risk and percentage risk for each factor using a statistical meta-analysis approach. The next step was to design a neural network computer model to predict the overall increase or decreased risk of cancer for individual patients. This would help to determine whether this prediction could be used as a tool to decide if a patient should be considered for testing and to predict diagnosis, as well as to suggest prevention measures to patients. Design: A meta-analysis of existing data was carried out to calculate relative risk, followed by design and implementation of a risk prediction computational model based on a neural network algorithm. Setting: Meta-analysis data were collated from various settings from around the world. Primary data to test the model were collected from a hospital clinic setting. Participants: Data from 40 patients notes currently suspected of having endometrial cancer and undergoing investigations and treatment were collected to test the software with their cancer diagnosis not revealed to the software developers. Main outcome measures: The forest plots allowed an overall relative risk and percentage risk to be calculated from all the risk data gathered from the studies. A neural network computational model to determine percentage risk for individual patients was developed, implemented, and evaluated. Results: The results show that the greatest percentage increased risk was due to BMI being above 25, with the risk increasing as BMI increases. A BMI of 25 or over gave an increased risk of 2.01%, a BMI of 30 or over gave an increase of 5.24%, and a BMI of 40 or over led to an increase of 6.9%. PCOS was the second highest increased risk at 4.2%. Diabetes, which is incidentally also linked to an increased BMI, gave a significant increased risk along with null parity and noncontinuous HRT of 1.54%, 1.2%, and 0.56% respectively. Decreased risk due to contraception was greatest with IUD (intrauterine device) and IUPD (intrauterine progesterone device) at −1.34% compared to −0.9% with oral. Continuous HRT at −0.75% and parity at −0.9% also decreased the risk. Using open-source patient data to test our computational model to determine risk, our results showed that the model is 98.6% accurate with an algorithm sensitivity 75% on average. Conclusions: In this study, we successfully determined the rank order of risk factors for endometrial cancer and calculated a pooled risk and risk percentage for each factor using a statistical meta-analysis approach. Then, using a computer neural network model system, we were able to model the overall increase or decreased risk of cancer and predict the cancer diagnosis for particular patients to an accuracy of over 98%. The neural network model developed in this study was shown to be a potentially useful tool in determining the percentage risk and predicting the possibility of a given patient developing endometrial cancer. As such, it could be a useful tool for clinicians to use in conjunction with other biomarkers in determining which patients warrant further preventative interventions to avert progressing to endometrial cancer. This result would allow for a reduction in the number of unnecessary invasive tests on patients. The model may also be used to suggest interventions to decrease the risk for a particular patient. The sensitivity of the model limits it at this stage due to the small percentage of positive cases in the datasets; however, since this model utilizes a neural network machine learning algorithm, it can be further improved by providing the system with more and larger datasets to allow further refinement of the neural network.

Metabolic shift precedes the resolution of inflammation in a cohort of patients undergoing bariatric and metabolic surgery

Bariatric and metabolic surgery has shown to promote weight loss and reduce systemic inflammation. However, the sequence and timing of events regarding metabolic improvement and inflammation resolution has been rarely explored. Furthermore, data on inflammatory markers of Th17 and Th1 cell responses after bariatric surgery is scarce. We conducted a prospective study in subjects with obesity that underwent bariatric and metabolic surgery, with follow-ups at 3 and 6 months. Anthropometric and metabolic markers such as insulin levels, HOMA-IR, and lipid parameters declined significantly 3 months after surgery; while hs-CRP, TNF-α, IL-1β, IL-6, and IL-8 serum concentrations decreased 6 months after the procedure. Concentrations of Th1 signature and driver cytokines, particularly IFN-γ, IL-12, and IL-18, and of Th17 driver IL-23 also decreased significantly after 6 months. Significant positive correlations between triglyceride levels and hs-CRP, IL-1β, and IFN-γ concentrations, and between Apo B and IFN-γ levels were observed 6 months after bariatric and metabolic surgery. In addition, BMI was associated with hs-CRP and TNF-α concentrations. Fat mass correlated with hs-CRP, TNF-α, and IL-12. Analysis of the temporality of metabolic and inflammatory events suggests that improvement in the metabolic status occurs before resolution of systemic inflammation and may be a requisite for the later event.

Curcumin improves insulin sensitivity and increases energy expenditure in high-fat-diet-induced obese mice associated with activation of FNDC5/irisin

OBJECTIVE

Curcumin (Cur) has a beneficial role in preventing metabolic dysfunctions; however, the underlying mechanism are not yet fully understood. The aim of this study was to evaluate whether the beneficial metabolic effects of curcumin are associated with the regulation of energy metabolism and activation of fibronectin type 3 domain-containing protein 5 (FNDC5)/irisin.

METHODS

We used cellular and molecular techniques to investigate the effects of Cur on C57 BL/6 mice that were fed either a control diet or a high-fat diet (HFD) with or without 0.2% Cur for 10 wk. Factors involved in energy metabolism, inflammatory responses, and insulin signaling, as well as the involvement of FNDC5/irisin pathway, were assessed.

RESULTS

Cur alleviated adiposity and suppressed inflammatory response in white adipose tissue (WAT) of HFD mice. Meanwhile, Cur administration increased plasma irisin concentration and improved insulin sensitivity of HFD mice. Cur increased the oxygen consumption and heat production and reduced respiratory exchange ratio (RES) in HFD mice, which were accompanied by the enhancement of metabolic activity in brown fat and inguinal WAT. Additionally, the improvement of basal metabolic rate by Cur may be partly regulated by the FNDC5/ p38 mitogen-activated protein kinase (p38 MAPK)/extracellular signal-related kinase (ERK) 1/2 pathway.

CONCLUSIONS

These findings demonstrated that dietary Cur alleviated diet-induced adiposity by improving insulin sensitivity and whole body energy metabolism via the FNDC5/p38 MAPK/ERK pathways.

A Low-Calorie Diet with or without Exercise Reduces Postprandial Aortic Waveform in Females with Obesity

PURPOSE

Arterial stiffness is considered a predictor of cardiovascular disease. Females have higher values of arterial stiffness than males, suggesting a greater risk of heart-related complications. Although a low-calorie diet (LCD) reduces fasting arterial stiffness, in part through weight loss, it is unknown if interval exercise (INT) adds to the benefit of LCD on fasting and postprandial arterial stiffness in females with obesity.

METHODS

Twenty-five females (47 ± 2.6 yr, 37.6 ± 1.3 kg·m-2) were randomized to 13 d of LCD (n = 12; mixed meals of ~1200 kcal·d-1) or LCD + INT (n = 13; 60 min·d-1 of supervised 3-min intervals at 90% HRpeak and 50% HRpeak). Arterial stiffness (augmentation index [AIx] and carotid-femoral pulse wave velocity [cfPWV]) and blood biochemistries were measured during a 75-g oral glucose tolerance test before and after the intervention to determine fasting and postprandial arterial stiffness as well as insulin sensitivity (simple index of insulin sensitivity [SIIS]) and inflammation (C-reactive protein, interleukin 8, and tumor necrosis factor alpha).

RESULTS

Although LCD + INT increased V˙O2peak and HDL compared with LCD (P = 0.04 and P < 0.01, respectively), both interventions decreased body fat, LDL, total cholesterol, and triglycerides (all P < 0.01) and increased SIIS (P = 0.03). Despite no effect on fasting AIx (P = 0.27), LCD and LCD + INT decreased AIx60min (-7.4% ± 4.3% vs -7.0% ± 5.0%, P = 0.04) and tAUC120min (-663 ± 263 vs -457 ± 406, P = 0.03). There were no changes in fasting cfPWV (P = 0.91) or cfPWV120min (P = 0.62). Increased SIIS and decreased interleukin 8 were associated with reduced fasting AIx (r = -0.44, P = 0.03, and r = 0.40, P = 0.055), whereas decreased C-reactive protein correlated with reduced postprandial AIx60min (r = 0.43, P = 0.04).

CONCLUSION

Independent of exercise, 13 d of LCD reduces postprandial AIx in females with obesity. Insulin sensitivity and inflammation correlated with improved arterial stiffness, suggesting unique mechanisms regulate fasted versus postprandial arterial stiffness.

Securidaca inappendiculata-Derived Xanthones Protected Joints from Degradation in Male Rats with Collagen-Induced Arthritis by Regulating PPAR-γ Signaling

Background

The bark of Securidaca inappendiculata Hassk. is traditionally used for treating inflammatory diseases and bone fractures in China. We have previously validated the xanthone-enriched fraction (XRF) of S. inappendiculata with anti-rheumatic potentials, but mechanism underlying the joints protective effects is still largely unknown.

Materials and Methods

The male rats with collagen-induced arthritis (CIA) were treated with XRF. The therapeutic efficacy of XRF was evaluated by arthritis score changes, morphological observation of paws, histological examinations and serological analyses. Protein expression in tissues and cells was investigated by either immunohistochemical or immunoblotting methods, while levels of mRNA expression were investigated by RT-qPCR. Metabolites in serum were detected by LC-MS approach. The joints homogenates were used for analyzing possible targeted genes by genome microarray analyses.

Results

Treatment with XRF and methotrexate (MTX) led to significant decrease in arthritis scores, and alleviated deformation of paws in CIA rats. In addition, XRF and MTX reduced circulating TNF-α, IL-1β and IL-17α in the serum and down-regulated TLR4/NF-κB and JNK pathways in joints of CIA rats. Compared to MTX, XRF-loading microemulsion significantly protected joints, which was accompanied by dramatic decrease in MMP3. Differential genes-based KEGG enrichment and metabolomics analysis suggested that XRF reduced fatty acids biosynthesis by regulating PPAR-γ signaling. S inappendiculata-derived 1,7-dihydroxy-3,4-dimethoxyxanthone (XAN) up-regulated PPAR-γ expression in macrophages, but suppressed it in pre-adipocytes in vitro, which was synchronized with SIRT1 changes. Adiponectin production and SCD-1 expression in pre-adipocytes were also decreased. Aside the direct inhibition on MMP3 expression in synovioblast, the presence of XAN in macrophages-pre-adipocytes co-culture system further reinforced this effect.

Conclusion

This study revealed the joint protective  advantages of the bioactive fraction from S. inappendiculata in CIA rats over MTX, and demonstrated that S. inappendiculata-derived xanthones suppressed the erosive nature of synovioblast acquired under inflammatory circumstances by regulating PPAR-γ signaling-controlled metabolism-immunity feedback.

The Inflammation Network in the Pathogenesis of Erectile Dysfunction: Attractive Potential Therapeutic Targets

BACKGROUND

Erectile dysfunction (ED) is an evolving health problem in the aging male population. Chronic low-grade inflammation is a critical component of ED pathogenesis and a probable intermediate stage of endothelial dysfunction, especially in metabolic diseases, with the inclusion of obesity, metabolic syndrome, and diabetes.

OBJECTIVE

This review will present an overview of preclinical and clinical data regarding common inflammatory mechanisms involved in the pathogenesis of ED associated with metabolic diseases and the effect of antiinflammatory drugs on ED.

METHODS

A literature search of existing pre-clinical and clinical studies was performed on databases [Pubmed (MEDLINE), Scopus, and Embase] from January 2000 to October 2019.

RESULTS

Low-grade inflammation is a possible pathological role in endothelial dysfunction as a consequence of ED and other related metabolic diseases. Increased inflammation and endothelial/prothrombotic markers can be associated with the presence and degree of ED. Pharmacological therapy and modification of lifestyle and risk factors may have a significant role in the recovery of erectile response through reduction of inflammatory marker levels.

CONCLUSION

Inflammation is the least common denominator in the pathology of ED and metabolic disorders. The inflammatory process of ED includes a shift in the complex interactions of cytokines, chemokines, and adhesion molecules. These data have established that anti-inflammatory agents could be used as a therapeutic opportunity in the prevention and treatment of ED. Further research on inflammation-related mechanisms underlying ED and the effect of therapeutic strategies aimed at reducing inflammation is required for a better understanding of the pathogenesis and successful management of ED.

GC-TOF-MS-Based Metabolomics Analyses of Liver and Intestinal Contents in the Overfed vs. Normally-Fed Geese

Simple Summary

Non-alcoholic fatty liver disease has been considered as one of the most important causes of liver disease, and it is a threat to human and animal health worldwide. Interestingly, goose fatty liver can reach 8–10 times the weight of normal liver with no overt pathological symptoms, suggesting that there are some protective mechanisms. Scientists have indicated that gut microbiota participate in the formation of non-alcoholic fatty liver disease in human and mammalian animals. However, it is unclear whether gut microbiota and their metabolites contribute to goose fatty liver. The aim of the present study was to investigate the metabolomic analyses of liver and intestinal contents in overfed vs. normally fed geese. The results showed that the formation of goose fatty liver is accompanied by obvious changes in the metabolic profiles of liver and intestinal contents. The intestinal metabolites can affect the formation of goose fatty liver by affecting the metabolisms of glucose and fatty acid, oxidative stress, and inflammatory reactions. These findings provide a basis for future work addressing the relationship between intestinal metabolites and the development of non-alcoholic fatty liver disease.

Abstract

No overt pathological symptoms are observed in the goose liver with severe steatosis, suggesting that geese may host unique protective mechanisms. Gas chromatography time-of-flight mass spectrometry-based metabolomics analyses of liver and intestinal contents in overfed vs. normally fed geese (26 geese in each treatment) were investigated. We found that overfeeding significantly changed the metabolic profiles of liver and intestinal contents. The differential metabolites mainly belong to fatty acids, amino acids, organic acids, and amines. The differential metabolites were involved in glycolysis/gluconeogenesis, glycerolipid metabolism, the pentose phosphate pathway, fatty acid degradation, the sphingolipid signaling pathway, and the biosynthesis of unsaturated fatty acids. Moreover, we determined the biological effects of arachidonic acid (ARA) and tetrahydrocorticosterone (TD) in goose primary hepatocytes and intestinal cells. Data showed that the mRNA expression of arachidonate 5-lipoxygenase (ALOX5) in goose primary intestinal cells was significantly induced by 0.50 mM ARA treatment. Cytochrome P-450 27A1 (CYP27A1) mRNA expression was significantly inhibited in goose primary hepatocytes by 1 µM TD treatment. In conclusion, the formation of goose fatty liver is accompanied by significant changes in the metabolic profiles of liver and intestinal contents, and the changes are closely related to the metabolisms of glucose and fatty acids, oxidative stress, and inflammatory reactions.

Effects of caloric restriction on retinal aging and neurodegeneration

Glaucoma is the most common neurodegenerative cause of irreversible blindness worldwide. Restricted caloric regimens are an attractive approach for delaying the progression of neurodegenerative diseases. Here we review the current literature on the effects of caloric restriction on retinal neurons, under physiological and pathological conditions. We focused on autophagy as one of the mechanisms modulated by restricted caloric regimens and involved in the death of retinal ganglion cells (RGCs) over the course of glaucoma.

Is Caloric Restriction Associated with Better Healthy Aging Outcomes? A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Global dietary patterns have gradually shifted toward a 'western type' with progressive increases in rates of metabolic imbalance. Recently, animal and human studies have revealed positive effects of caloric restriction (CR) on many health domains, giving new knowledge for prevention of ill and health promotion; Methods: We conducted a systematic review (SR) of randomized controlled trials (RCTs) investigating the role of CR on health status in adults. A meta-analysis was performed on anthropometric, cardiovascular and metabolic outcomes; Results: A total of 29 articles were retrieved including data from eight RCTs. All included RCTs were at low risk for performance bias related to objective outcomes. Collectively, articles included 704 subjects. Among the 334 subjects subjected to CR, the compliance with the intervention appeared generally high. Meta-analyses proved benefit of CR on reduction of body weight, BMI, fat mass, total cholesterol, while a minor impact was shown for LDL, fasting glucose and insulin levels. No effect emerged for HDL and blood pressure after CR. Data were insufficient for other hormone variables in relation to meta-analysis of CR effects; Conclusion: CR is a nutritional pattern linked to improved cardiometabolic status. However, evidence is limited on the multidimensional aspects of health and requires more studies of high quality to identify the precise impact of CR on health status and longevity.

Anti-Inflammatory Potential of Cultured Ginseng Roots Extract in Lipopolysaccharide-Stimulated Mouse Macrophages and Adipocytes

Wild ginseng, Panax ginseng Meyer, is a traditional medicine widely used in Asia. Due to low reward and high costs, wild ginseng is produced by a plant cell culture technique called cultured ginseng roots (GR). The health benefits of wild ginseng have been well studied, but the potential health effects of GR are largely unknown. Thus, we investigated the role of a GR extract (GRE) on inflammatory responses. We firstly investigated the anti-inflammatory potential of GRE in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. GRE (100 μg/mL) dampened pro-inflammatory gene expression, cytokine release, reactive oxygen species (ROS) production, and mitogen-activated protein kinase (MAPK) activation. These anti-inflammatory responses by GRE were confirmed in mouse bone marrow-derived macrophages (BMDMs), which showed that GRE could inhibit inflammation with the induction of antioxidant levels. LPS was recently reported to impair mitochondrial bioenergetics in mouse macrophages. We next measured the mitochondrial oxygen consumption rate (OCR), determining mitochondrial function. LPS treatment downregulated OCR; however, GRE partially restored the LPS-mediated energy homeostasis defects. Furthermore, GRE-pretreated conditioned media (CM) obtained from mouse macrophages decreased CM-mediated adipocyte inflammation. Collectively, these data suggested that GRE attenuated LPS-induced inflammation, and it might be partially involved in the protection from mitochondrial dysfunction in macrophages and adipocytes.

Effects of Dietary Fat Sources during Late Gestation on Colostrum Quality and Mammary Gland Inflammation in Lipopolysaccharide-Challenged Sows

Simple Summary

In the present study, late gestating sows were challenged with lipopolysaccharide (LPS) endotoxin, which can impair the immune system of mammary gland cells and result in an inflammatory response. Additionally, the LPS-treated sows were fed 3% soybean oil (SO), 3% coconut oil (CO) or 3% fish oil (FO) diets and were used to study the effect of fat sources on the colostrum quality and mammary gland inflammation of sows exposed to immune challenge. The results show that FO inclusion exerted anti-inflammatory effects in mammary glands and counteracted the LPS-induced damaged colostrum synthesis and pro-inflammatory response when compared to CO diets. These findings suggest that fatty acid profiles of different oil types in late gestation differentially affect metabolic health in sows, but a longer period of FO supplementation to sows is needed to determine a positive effect on piglets.

Abstract

This study aimed to investigate the effects of maternal lipopolysaccharide (LPS) challenge and dietary fat sources on colostrum quality and inflammatory response in sows. Sixty Landrace × Yorkshire sows were randomly assigned to three dietary treatments supplemented with 3% soybean oil (SO), 3% coconut oil (CO) or 3% fish oil (FO), respectively, from Day 90 of gestation until parturition. On Day 112 of gestation, half the sows from each dietary treatment were challenged with LPS (10 μg/kg BW) or saline. The results showed that maternal LPS challenge decreased colostrum yield and dry matter content. A similar pattern of changes was observed for body weight gain and colostrum intake in piglets from LPS-challenged sows. Maternal LPS challenge increased the levels of tumor necrosis factor α (TNFα), interleukin 1β (IL1β) and IL6 in colostum, and the mRNA abundance of IL6, IL1β and TNFα and the phosphorylation level of p65 in mammary glands. However, the responses of these variables to LPS treatment were lower in sows fed a FO diet. In conclusion, maternal immune challenge reduced the growth performance of piglets by decreasing colostrum yield and intake by piglets, and dietary supplementation with FO in sows attenuates the LPS-induced inflammatory response in mammary glands.

Feeding restriction alleviates high carbohydrate diet-induced oxidative stress and inflammation of Megalobrama amblycephala by activating the AMPK-SIRT1 pathway

This study investigated the effects of restricted feeding on the growth performance, oxidative stress and inflammation of Megalobrama amblycephala fed high-carbohydrate (HC) diets. Fish (46.94 ± 0.04 g) were randomly assigned to four groups containing the satiation of a control diet (30% carbohydrate) and three satiate levels (100% (HC1), 80% (HC2) and 60% (HC3)) of the HC diets (43% carbohydrate) for 8 weeks. Results showed that HC1 diet remarkably decreased final weight (FW), weight gain rate (WGR), specific growth rate (SGR), feed conversion ratio (FCR), hepatic activities of total anti-oxidation capacity (T-AOC), superoxide dismutase (SOD) and catalase (CAT), the AMP/ATP ratio, the p-AMPKα/t-AMPKα ratio, sirtuin-1 (SIRT1) protein expression and hepatic transcriptions of AMPKα2, SIRT1, nuclear factor erythroid 2-related factor 2 (Nrf2), catalase (CAT), manganese superoxide dismutase (Mn-SOD), glutathione peroxidase 1 (GPx1) and interleukin10 (IL 10) compared to the control group, whereas the opposite was true for protein efficiency ratio (PER), nitrogen retention efficiency (NRE), energy retention efficiency (ERE), plasma glucose levels, alanine transaminase (AST) and aspartate aminotransferase (ALT) activities, hepatic contents of malondialdehyde (MDA), tumour necrosis factor α (TNF α) and interleukin 1β (IL 1β), ATP and AMP contents and hepatic transcriptions of kelch-like ECH associating protein 1 (Keap1), IkB kinase α (IKK α), nuclear factor kappa B (NF-κB), TNF α, IL 1β, interleukin 6 (IL 6) and transforming growth factor β (TGF β). As for the HC groups, fish fed the HC2 diet obtained relatively high values of SGR, PER, NRE, ERE, hepatic activities of T-AOC, SOD and CAT, the AMP/ATP ratio, the p-AMPKα/t-AMPKα ratio, SIRT1 protein expression and hepatic transcriptions of AMPKα2, Nrf2, CAT, copper/zinc superoxide dismutase (Cu/Zn-SOD), Mn-SOD, GPx1, glutathione S-transferase (GST) and interleukin10 (IL 10), while the opposite was true for hepatic content of IL 6 and transcription of IKK α. Overall, an 80% satiation improved the growth performance and alleviated the oxidative stress and inflammation of blunt snout bream fed HC diets via the activation of the AMPK-SIRT1 pathway and the up-regulation of the activities and transcriptions of Nrf2-modulated antioxidant enzymes coupled with the depression of the levels and transcriptions of the NF-κB-mediated pro-inflammatory cytokines.

Metabolomics Analysis Reveals Therapeutic Effects of α-Mangostin on Collagen-Induced Arthritis in Rats by Down-regulating Nicotinamide Phosphoribosyltransferase

α-Mangostin (MAN) is a bioactive compound isolated from pericarp of mangosteen (Garcinia mangostana Linn.) with significant anti-rheumatic potentials. The purpose of this study was to explore the mechanisms underlying its therapeutic effects on collagen-induced arthritis (CIA) in rats with metabolomics approaches. Therapeutic effects of MAN on CIA were assessed by radiographic, histological, and immunohistochemical methods. Metabolic profiles of rats were characterized based on UPLC-MS/MS analysis of urine samples, followed by verification in HFLS-RA cells using a variety of toxicological and biochemical assays. We found that MAN treatment protected joint structures in CIA rats and caused a decrease of nicotinamide mononucleotide (NMN) in urine. The levels of nicotinamide phosphoribosyltransferase (NAMPT) were reduced in fibroblast-like synoviocytes by MAN both in vivo and in vitro, which was accompanied with a decline in nicotinamide adenine dinucleotide (NAD) production. Secretion of extracellular NAMPT (eNAMPT) in HFLS-RA cells was also decreased upon MAN treatment, which lagged behind the changes of its intracellular counterpart (iNAMPT). Co-treatment with NMN raised the secretion of eNAMPT and restored the decline of p-p65 and TNF-α induced by MAN in vitro. Sirt1 expression was down-regulated under MAN treatments too. These results suggest that MAN treatment suppressed NAD production by inhibiting iNAMPT expression, which in turn decreased eNAMPT secretion and alleviated NF-κB-mediated inflammations in CIA rats.

A novel nutritional supplement prevents muscle loss and accelerates muscle mass recovery in caloric-restricted mice

BACKGROUND

Muscle atrophy is defined as decreased muscle mass, associated with aging as well as with various chronic diseases and is a fundamental cause of frailty, functional decline and disability. Frailty represents a huge potential public health issue worldwide with high impact on healthcare costs. A major clinical issue is therefore to devise new strategies preventing muscle atrophy. In this study, we tested the efficacy of Vital01, a novel oral nutritional supplement (ONS), on body weight and muscle mass using a caloric restriction-induced mouse model for muscle atrophy.

METHODS

Mice were calorically restricted for 2 weeks to induce muscle atrophy: one control group received 60% kcal of the normal chow diet and one intervention group received 30% kcal chow and 30 kcal% Vital01. The effects on body weight, lean body mass, muscle histology and transcriptome were assessed. In addition, the effects of Vital01, in mice with established muscle atrophy, were assessed and compared to a standard ONS. To this end, mice were first calorically restricted on a 60% kcal chow diet and then refed with either 100 kcal% chow, a mix of Vital01 (receiving 60% kcal chow and 40 kcal% Vital01) or with a mix of standard, widely prescribed ONS (receiving 60 kcal% chow and 40 kcal% Fortisip Compact).

RESULTS

Vital01 attenuated weight loss (-15% weight loss for Vital01 vs. -25% for control group, p < 0.01) and loss of muscle mass (Vital01 with -13%, -12% and -18%, respectively, for gastrocnemius, quadriceps and tibialis vs. 25%, -23% and -28%, respectively, for control group, all p < 0.05) and also restored body weight, fat and muscle mass more efficiently when compared to Fortisip Compact. As assessed by transcriptome analysis and Western blotting of key proteins (e.g. phospoAKT, mTOR and S6K), Vital01 attenuated the catabolic and anabolic signaling pathways induced by caloric restriction and modulated inflammatory and mitochondrial pathways. In addition, Vital01 affected pathways related to matrix proteins/collagens homeostasis and tended to reduce caloric restriction-induced collagen fiber density in the quadriceps (with -27%, p = 0.051).

CONCLUSIONS

We demonstrate that Vital01 preserves muscle mass in a calorically restricted mouse model for muscle atrophy. Vital01 had preventive effects when administered during development of muscle atrophy. Furthermore, when administered in a therapeutic setting to mice with established muscle atrophy, Vital01 rapidly restored body weight and accelerated the recurrence of fat and lean body mass more efficiently than Fortisip Compact. Bioinformatics analysis of gene expression data identified regulatory pathways that were specifically influenced by Vital01 in muscle.

Chronic Low-grade Inflammatory Phenotype (CLIP) and Senescent Immune Dysregulation

PURPOSE

The aim was to provide an overview of chronic low-grade inflammatory phenotype (CLIP) and evidence for its role in the pathogenesis of frailty and other chronic conditions as well as potential causative factors and interventions.

METHODS

We reviewed evidence from published clinical and laboratory studies and summarized the opinions of experts from published reviews.

FINDINGS

CLIP is a low-grade, systemic, unresolved, and smoldering chronic inflammatory state clearly indicated by a 2- to 4-fold increase in serum levels of inflammatory mediators, such as interleukin-6 and C-reactive protein. It involves many other cellular and molecular inflammatory mediators. CLIP typically occurs during aging, also known as "inflammaging," and is an integral part of the spectrum of immunosenescence. Causative factors likely include persistent viral infections, particularly chronic cytomegalovirus infection, cellular senescence, failure to eliminate degraded materials and waste products, dysregulated microbiota and gut permeability, obesity, and others. Substantial evidence supports CLIP as a powerful contributing factor to frailty and many other chronic conditions and adverse health outcomes. Many of the inflammatory mediators and their regulatory mechanisms in CLIP may serve as potential targets for therapeutic intervention. However, development of new interventional strategies for CLIP and its associated chronic conditions should take the complexity of the inflammatory network into consideration. Nonpharmacologic interventions, such as caloric restriction and exercise, may have significant impact on CLIP and its causative factors, leading to substantial health benefits. Metformin and resveratrol have anti-inflammatory property and may serve as a promising therapeutic agent for treatment of CLIP and frailty.

IMPLICATIONS

CLIP is a chronic inflammatory pathophysiologic process that plays an important role in the pathogenesis of frailty and many other chronic conditions. Improving our understanding of this phenotype may provide opportunities to identify potential targets of effective prevention and therapeutic strategies for frailty and other CLIP-associated conditions.

The ubiquitin ligase KBTBD8 regulates PKM1 levels via Erk1/2 and Aurora A to ensure oocyte quality

Tight control of energy metabolism is essential for normal cell function and organism survival. PKM (pyruvate kinase, muscle) isoforms 1 and 2 originate from alternative splicing of PKM pre-mRNA. They are key enzymes in oxidative phosphorylation and aerobic glycolysis, respectively, and are essential for ATP generation. The PKM1:PKM2 expression ratio changes with development and differentiation, and may also vary under metabolic stress and other conditions. Until now, there have been no reports about the function and regulation of PKM isozymes in oocytes. Here, we demonstrate that PKM1 or PKM2 depletion significantly disrupts ATP levels and mitochondrial integrity, and exacerbates free-radical generation and apoptosis in mouse oocytes. We also show that KBTBD8, a female fertility factor in the KBTBD ubiquitin ligase family, selectively regulates PKM1 levels through a signaling cascade that includes Erk1/2 and Aurora A kinases as intermediates. Finally, using RNA sequencing and protein network analysis, we identify several regulatory proteins that may be govern generation of mature PKM1 mRNA. These results suggest KBTBD8 affects PKM1 levels in oocytes via a KBTBD8→Erk1/2→Aurora A axis, and may also affect other essential processes involved in maintaining oocyte quality.

Adipose tissue is less responsive to food restriction anti-inflammatory effects than liver, muscle, and brain in mice

High caloric intake promotes chronic inflammation, insulin resistance, and chronic diseases such as type-2 diabetes, which may be prevented by food restriction (FR). The effect of FR on expression of pro-inflammatory and anti-inflammatory genes in adipose tissue, liver, muscle, and brain was compared. Male Swiss mice were submitted to FR (FR group) or had free access to food (control group) during 56 days. The liver, gastrocnemius muscle, brain, and epididymal white adipose tissue (WAT) were collected for analysis of gene expressions. FR attenuated inflammation in the liver, brain, and gastrocnemius muscle but did not markedly change inflammatory gene expression in epididymal WAT. We concluded that adipose tissue was less responsive to FR in terms of gene expression of pro-inflammatory and anti-inflammatory genes.

Interleukin-12 as a biomarker of the beneficial effects of food restriction in mice receiving high fat diet or high carbohydrate diet

The impact of food restriction (FR) during 56 days on serum levels of cytokines in mice fed a high-fat diet (HFD) or high-carbohydrate diet (HCD) were evaluated. The amount of food was reduced 50% for HFD-FR and HCD-FR groups compared to mice receiving free access to HFD (HFD group) or HCD (HCD group). We quantified the serum levels of basic fibroblast growth factor, granulocyte-macrophage colony-stimulating factor, inducible protein 10, interferon γ, interleukin 1α (IL-1α), IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, IL-13, IL-17, keratinocyte chemoattractant, macrophage inflammatory protein-1α, monocyte chemotactic protein 1, monokine induced by IFN-γ, and tumor necrosis factor α. Only IL-12 levels were lower (P<0.05), for both HFD-FR (HFD-FR vs HFD) and HCD-FR (HCD-FR vs HCD). Therefore, IL-12 levels could be considered a biological marker of the beneficial effects of FR.

Metabolic memory of dietary restriction ameliorates DNA damage and adipocyte size in mouse visceral adipose tissue

Dietary restriction (DR) is thought to exert its beneficial effects on healthspan at least partially by a senolytic and senostatic action, i.e. by reducing frequencies of cells with markers of DNA damage and senescence in multiple tissues. Due to its importance in metabolic and inflammation regulation, fat is a prime tissue for health span determination as well as a prime target for DR. We aimed to determine here whether the beneficial effects of DR would be retained over a subsequent period of ad libitum (AL) feeding. Male mice were kept under either 40% DR or AL feeding regimes from 3 to 12 months of age and then either switched back to the opposite feeding regimen or kept in the same state for another 3 months. Visceral adipose tissue from 4 to 5 mice per group for all conditions was analysed for markers of senescence (adipocyte size, γH2A.X, p16, p21) and inflammation (e.g. IL-6, TNFα, IL-1β) using immuno-staining or qPCR. Macrophages were detected by immunohistochemistry. We found that both 9 and 12 months DR (long term) as well as 3 month (short term, mid-life onset) DR reduced the number of cells harbouring DNA damage and adipocyte size (area and perimeter) in visceral adipocytes with similar efficiency. Importantly, beneficial health markers induced by DR such as small adipocyte size and low DNA damage were maintained for at least 3 month after termination of DR, demonstrating that the previously identified 'metabolic memory' of the DR state in male mice extends to senescence markers in visceral fat.

α-Mangostin Alleviated Lipopolysaccharide Induced Acute Lung Injury in Rats by Suppressing NAMPT/NAD Controlled Inflammatory Reactions

α-Mangostin (MAN) is a bioactive xanthone isolated from mangosteen. This study was designed to investigate its therapeutic effects on acute lung injury (ALI) and explore the underlying mechanisms of action. Rats from treatment groups were subject to oral administration of MAN for 3 consecutive days beforehand, and then ALI was induced in all the rats except for normal controls via an intraperitoneal injection with lipopolysaccharide. The severity of disease was evaluated by histological examination and hematological analysis. Protein expressions in tissues and cells were examined with immunohistochemical and immunoblotting methods, respectively. The levels of cytokines and nicotinamide adenine dinucleotide (NAD) were determined using ELISA and colorimetric kits, respectively. It was found that MAN treatment significantly improved histological conditions, reduced leucocytes counts, relieved oxidative stress, and declined TNF-α levels in ALI rats. Meanwhile, MAN treatment decreased expressions of nicotinamide phosphoribosyltransferase (NAMPT) and Sirt1 both in vivo and in vitro, which was accompanied with a synchronized decline of NAD and TNF-α. Immunoblotting assay further showed that MAN downregulated HMGB1, TLR4, and p-p65 in RAW 264.7 cells. MAN induced declines of both HMGB1/TLR4/p-p65 and TNF-α were substantially reversed by cotreatment with nicotinamide mononucleotide or NAD. These results suggest that downregulation of NAMPT/NAD by MAN treatments contributes to the alleviation of TLR4/NF-κB-mediated inflammations in macrophage, which is essential for amelioration of ALI in rats.

Effect of Low-Fat Diet in Obese Mice Lacking Toll-like Receptors

Background: This study aimed at assessing the effect of a low-fat diet (LFD) in obese mice lacking toll–like receptors (Tlr) and understanding the expression and regulation of microRNAs during weight reduction. Methods: C57BL/6, Tlr5^−/−, Tlr2^−/− and Tlr4^−/− mice were used in this study. A group of mice were fed with a high-fat diet (HFD) (58% kcal) for 12 weeks to induce obesity (diet-induced obesity, DIO). Another group that had been fed with HFD for eight weeks (obese mice) were switched to a low-fat diet (LFD) (10.5% kcal) for the next four weeks to reduce their body weight. The control mice were fed with a standard AIN-76A diet for the entire 12 weeks. The body weight of the mice was measured weekly. At the end of the experiment, epididymal fat weight and adipocyte size were measured. The differentially expressed miRNAs in the fat tissue was determined by next-generation sequencing with real-time quantitative reverse transcription polymerase chain reaction (RT–qPCR). Target prediction and functional annotation of miRNAs were performed using miRSystem database. Results: Switching to LFD significantly reduced the body weight and epididymal fat mass in the HFD-fed C57BL/6 and Tlr5^−/− mice but not in Tlr2^−/− and Tlr4^−/− mice. Weight reduction significantly decreased the size of adipocytes in C57BL/6 but not in the Tlr knockout mice. In Tlr2^−/− and Tlr4^−/− mice, feeding with HFD and the subsequent weight reduction resulted in an aberrant miRNA expression in the epididymal fat tissue unlike in C57BL/6 and Tlr5^−/−. However, target prediction and functional annotation by miRSystem database revealed that all the top 10 Kyoto Encyclopedia of Genes and Genomes (KEGG) database pathways of the dysregulated miRNAs during weight reduction in the C57BL/6 mice were also found in the regulated pathways of Tlr5^−/−, Tlr2^−/−, and Tlr4^−/− strains. However, among these pathways, gene sets involved in arginine and proline metabolism and glutathione metabolism were mainly involved in the Tlr knockout mice but not in the C57BL/6 mice. Conclusions: In this study, we demonstrated that feeding of LFD leads to significant body weight reduction in C57BL/6 and Tlr5^−/− mice, but not in Tlr2^−/− and Tlr4^−/− mice. Significant reduction in the size of adipocytes of epididymal fat was only found in C57BL/6, but not in Tlr5^−/−, Tlr2^−/−, and Tlr4^−/− mice. The dysregulated miRNAs in Tlr2^−/− and Tlr4^−/− mice were different from those in C57BL/6 and Tlr5^−/− strains. Among those miRNA-regulated pathways, arginine and proline metabolism as well as glutathione metabolism may have important roles in the Tlr knockout mice rather than in C57BL/6 mice.

Inflammaging: a new immune-metabolic viewpoint for age-related diseases

Ageing and age-related diseases share some basic mechanistic pillars that largely converge on inflammation. During ageing, chronic, sterile, low-grade inflammation - called inflammaging - develops, which contributes to the pathogenesis of age-related diseases. From an evolutionary perspective, a variety of stimuli sustain inflammaging, including pathogens (non-self), endogenous cell debris and misplaced molecules (self) and nutrients and gut microbiota (quasi-self). A limited number of receptors, whose degeneracy allows them to recognize many signals and to activate the innate immune responses, sense these stimuli. In this situation, metaflammation (the metabolic inflammation accompanying metabolic diseases) is thought to be the form of chronic inflammation that is driven by nutrient excess or overnutrition; metaflammation is characterized by the same mechanisms underpinning inflammaging. The gut microbiota has a central role in both metaflammation and inflammaging owing to its ability to release inflammatory products, contribute to circadian rhythms and crosstalk with other organs and systems. We argue that chronic diseases are not only the result of ageing and inflammaging; these diseases also accelerate the ageing process and can be considered a manifestation of accelerated ageing. Finally, we propose the use of new biomarkers (DNA methylation, glycomics, metabolomics and lipidomics) that are capable of assessing biological versus chronological age in metabolic diseases.

Raspberry alleviates obesity-induced inflammation and insulin resistance in skeletal muscle through activation of AMP-activated protein kinase (AMPK) α1

OBJECTIVE

Through dynamic means, etiological factors, including chronic inflammation and insulin resistance have the potential to perpetuate metabolic incidences such as type 2 diabetes and obesity. Abatement of such syndromes can be achieved by complex mechanisms initiated through bioactive compounds such as polyphenols derived from fruits. Using a whole-fruit approach, the effects of dietary red raspberry, which is rich in polyphenols, on inflammatory responses and insulin resistance in the skeletal muscles of Mus musculus were studied along with the potential role of AMP-activated protein kinase (AMPK) to act as a key mediator.

SUBJECTS

Wild-type (WT) mice and mice deficient in the catalytic subunit (α1) of AMPK (AMPKα1-/-) were fed with a high-fat diet (HFD) or HFD supplemented with raspberry (5% dry weight) for 10 weeks. Factors involved in inflammatory responses, insulin signaling transduction, and mitochondrial biogenesis were evaluated.

RESULTS

Dietary raspberry reduced ectopic lipid storage, alleviated inflammation responses, improved whole-body insulin sensitivity, and promoted mitochondrial biogenesis in the skeletal muscle of WT mice, but not AMPKα1-/- mice.

CONCLUSIONS

AMPKα1 is an important mediator for the beneficial effects of raspberry through alleviating inflammatory responses and sensitizing insulin signaling in skeletal muscle of HFD-fed mice.