Voluntary exercise blocks Western diet-induced gene expression of the chemokines CXCL10 and CCL2 in the prefrontal cortex

Minocycline treatment attenuates neurobehavioural abnormalities and neurostructural aberrations in the medial prefrontal cortex in mice fed a high-fat diet during adolescence

A preference for and overconsumption of a high-fat diet (HFD) are common among adolescents and are recognized as risk factors for multiple mental disorders. The protracted maturation of the medial prefrontal cortex (mPFC), a key brain structure that plays a critical role in mental functions that are essential for both developing and mature individuals (including emotional processing, decision making, risk assessment, and creative thinking), during adolescence renders it more vulnerable to the environmental insults experienced during this critical developmental window. However, the effects of HFD consumption during adolescence on mPFC-related behaviours and the underlying mechanisms need to be further investigated. In this study, we observed that mice fed a HFD throughout adolescence developed depressive- and anxiety-like behaviours and distinctively increased risk-avoidance behaviour, accompanied by morphological aberrations of both pyramidal neuron and microglia in the mPFC. The systemic administration of minocycline, a well-known broad-spectrum antibiotic, effectively attenuated the adverse effects of HFD consumption during adolescence on neurobehaviours and the morphology of pyramidal neurons in the mPFC. This study provides new insights into the psychological effects of long-term HFD consumption during adolescence and indicates the existence of a window during which microglial stabilization may be a promising strategy to protect against the HFD consumption-induced increase in the risk of psychiatric disorders.

Voluntary exercise suppresses inflammation and improves insulin resistance in the arcuate nucleus and ventral tegmental area in mice on a high-fat diet

A high-fat diet (HFD) causes inflammation with an increase in microglial activity in the hypothalamic arcuate nucleus (ARC) and ventral tegmental area (VTA), resulting in insulin resistance in both regions. This leads to a deterioration in glucose and energy metabolism. The effect of voluntary exercise on HFD-induced inflammation in the central nervous system (CNS) remains unclear. To clarify the effects of voluntary exercise on the CNS, 8-week-old male C57BL6 mice were fed a chow diet (CHD) or HFD for 4 weeks; each group was further divided into running exercise (EX+) on a wheel and no exercise (EX-) groups. The expression of the inflammatory cytokine, tumor necrosis factor alpha (TNFα), in the ARC and VTA was significantly increased in the HFD/EX- group, with an increase of microglial activity noted, compared to the CHD/EX- group. The expression of TNFα was significantly suppressed, with a decrease of microglial activity, in the HFD/EX+ compared to HFD/EX- group. Insulin resistance in the ARC and VTA was improved with the suppression of TNFα expression. The HFD/EX- group showed significant weight gain and impaired glucose metabolism compared to the CHD/EX- group. The HFD/EX+ group showed an improvement in glucose and energy metabolism compared to the HFD/EX- group. In addition, voluntary wheel running suppressed HFD-induced inflammation in the ARC, with a decrease in microglial activity observed independently of weight changes. Our data suggest that voluntary exercise prevents obesity and improves glucose metabolism by suppressing inflammation in the ARC and VTA under HFD conditions.

The Role of Chemokines in Obesity and Exercise-Induced Weight Loss

Obesity is a global health crisis that is closely interrelated to many chronic diseases, such as cardiovascular disease and diabetes. This review provides an in-depth analysis of specific chemokines involved in the development of obesity, including C-C motif chemokine ligand 2 (CCL2), CCL3, CCL5, CCL7, C-X-C motif chemokine ligand 8 (CXCL8), CXCL9, CXCL10, CXCL14, and XCL1 (lymphotactin). These chemokines exacerbate the symptoms of obesity by either promoting the inflammatory response or by influencing metabolic pathways and recruiting immune cells. Additionally, the research highlights the positive effect of exercise on modulating chemokine expression in the obese state. Notably, it explores the potential effects of both aerobic exercises and combined aerobic and resistance training in lowering levels of inflammatory mediators, reducing insulin resistance, and improving metabolic health. These findings suggest new strategies for obesity intervention through the modulation of chemokine levels by exercise, providing fresh perspectives and directions for the treatment of obesity and future research.

Exercise accelerates recruitment of CD8+ T cell to promotes anti-tumor immunity in lung cancer via epinephrine

BACKGROUND AND PURPOSE

In recent years, there has been extensive research on the role of exercise as an adjunctive therapy for cancer. However, the potential mechanisms underlying the anti-tumor therapy of exercise in lung cancer remain to be fully elucidated. As such, our study aims to confirm whether exercise-induced elevation of epinephrine can accelerate CD8+ T cell recruitment through modulation of chemokines and thus ultimately inhibit tumor progression.

METHOD

C57BL/6 mice were subcutaneously inoculated with Lewis lung cancer cells (LLCs) to establish a subcutaneous tumor model. The tumor mice were randomly divided into different groups to performed a moderate-intensity exercise program on a treadmill for 5 consecutive days a week, 45 min a day. The blood samples and tumor tissues were collected after exercise for IHC, RT-qPCR, ELISA and Western blot. In addition, another group of mice received daily epinephrine treatment for two weeks (0.05 mg/mL, 200 µL i.p.) (EPI, n = 8) to replicate the effects of exercise on tumors in vivo. Lewis lung cancer cells were treated with different concentrations of epinephrine (0, 5, 10, 20 µM) to detect the effect of epinephrine on chemokine levels via ELISA and RT-qPCR.

RESULTS

This study reveals that both pre- and post-cancer exercise effectively impede the tumor progression. Exercise led to an increase in EPI levels and the infiltration of CD8+ T cell into the lung tumor. Exercise-induced elevation of EPI is involved in the regulation of Ccl5 and Cxcl10 levels further leading to enhanced CD8+ T cell infiltration and ultimately inhibiting tumor progression.

CONCLUSION

Exercise training enhance the anti-tumor immunity of lung cancer individuals. These findings will provide valuable insights for the future application of exercise therapy in clinical practice.

Exercise-induced modulation of Interferon-signature: a therapeutic route toward management of Systemic Lupus Erythematosus

Systemic Lupus Erythematosus (SLE) is a multisystemic autoimmune disorder characterized by flares-ups/remissions with a complex clinical picture related to disease severity and organ/tissue injury, which, if left untreated, may result in permanent damage. Enhanced fatigue and pain perception, worsened quality of life (QoL) and outcome are constant, albeit symptoms may differ. An aberrant SLE immunoprofiling, note as "interferon (IFN)α-signature", is acknowledged to break immunotolerance. Recently, a deregulated "IFNγ-signature" is suggested to silently precede/trigger IFNα profile before clinical manifestations. IFNα- and IFNγ-over-signaling merge in cytokine/chemokine overexpression exacerbating autoimmunity. Remission achievement and QoL improvement are the main goals. The current therapy (i.e., corticosteroids, immunosuppressants) aims to downregulate immune over-response. Exercise could be a safe treatment due to its ever-emerging ability to shape and re-balance immune system without harmful side-effects; in addition, it improves cardiorespiratory capacity and musculoskeletal strength/power, usually impaired in SLE. Nevertheless, exercise is not yet included in SLE care plans. Furthermore, due to the fear to worsening pain/fatigue, SLE subjects experience kinesiophobia and sedentary lifestyle, worsening physical health. Training SLE patients to exercise is mandatory to fight inactive behavior and ameliorate health. This review aims to focus the attention on the role of exercise as a non-pharmacological therapy in SLE, considering its ability to mitigate IFN-signature and rebalance (auto)immune response. To this purpose, the significance of IFNα- and IFNγ-signaling in SLE etiopathogenesis will be addressed first and discussed thereafter as biotarget of exercise. Comments are addressed on the need to make aware all SLE care professional figures to promote exercise for health patients.

Atorvastatin Inhibits High-Fat Diet-Induced Lipid Metabolism Disorders in Rats by Inhibiting Bacteroides Reduction and Improving Metabolism

PURPOSE

The prevalence of hyperlipidemia and related illnesses is on its rise, and atorvastatin is the frequently used hypolipidemic agent. However, there is still uncertainty about the mechanisms, especially the relationship between the lipid-lowering effect, intestinal microbiome, and metabolic profiles. We aim to intensively explain the mechanism of the hypolipidemic effect of atorvastatin through multi-omics perspective of intestinal microbiome and metabolomics.

METHODS

Multi-omics methods play an increasingly important role in the analysis of intestinal triggers and evaluation of metabolic disorders such as obesity, hyperlipidemia, and diabetes. Therefore, we were prompted to explore intestinal triggers, underlying biomarkers, and potential intervention targets of atorvastatin in the treatment of dyslipidemia through multi-omics. To achieve this, SPF Wistar rats were fed a high-fat diet or normal diet for 8 weeks. Atorvastatin was then administered to high-fat diet-fed rats.

RESULTS

By altering intestinal microbiome, a high-fat diet can affect feces and plasma metabolic profiles. Treatment with atorvastatin possibly increases the abundance of Bacteroides, thereby improving "propanoate metabolism" and "glycine, serine and threonine metabolism" in feces and plasma, and contributing to blood lipid reduction.

CONCLUSION

Our study elucidated the intestinal triggers and metabolites of high-fat diet-induced dyslipidemia from the perspective of intestinal microbiome and metabolomics. It equally identified potential intervention targets of atorvastatin. This further explains the mechanism of the hypolipidemic effect of atorvastatin from a multi-omics perspective.

Effects of 8-week noncontinuous aerobic exercise on the levels of CCL2, CCL5, and their respective receptors in female BALB/C mice suffering from breast cancer

Background:

Recently, the importance of chemokines and their receptors in carcinogenesis and the protective role of aerobic exercise in primary cancer development and progression is highlighted. Based on the facts that endurance exercise may result in hypoxia condition, and in addition, the effect of exercise therapy on the levels of CCL2, CCR2, and their related receptors in breast cancer (BC) model has not been investigated so far, therefore we aimed to evaluate the effect of eight-week noncontinuous aerobic training on the levels of CCL2, CCL5, and their related receptors; CCR2 and CCR5 in female BALB/C mice with BC.

Methods:

Thirty-two BALB/C mice (4–5 weeks old) were randomly divided to four 8-member groups of control and experimental. The experimental group received 8 weeks of noncontinuous aerobic exercises (AEs) while the control group did not receive any exercises during these 8 weeks. After last of experiment, 5 ml of blood was taken from each rat's lower inferior vein. The plasma levels of CCL2 and CCL5 were measured by ELISA and CCR2 and CCR5 by western blot. Tumor volume also measured in each step. Data were analyzed using the ANOVA test and the SPSS v. 0.24 Software.

Results:

After 8 weeks of participation in noncontinuous AEs, a statistically significant decrease was made between the control and experimental groups in terms of CCL2, CCL5, and CCR2 levels, as well as tumor volume. However, there was no significant difference between groups in terms of CCR5 level.

Conclusions:

It can be concluded that the 8 weeks of noncontinuous AEs did not result in CCR5 reduction while resulting in a statistically significant decrease in CCL2, CCL5, CCR2, and tumor volume.

Treadmill Exercise Attenuates Cerebral Ischemia-Reperfusion Injury by Promoting Activation of M2 Microglia via Upregulation of Interleukin-4

Background: Exercise has been proven to be an effective therapy for stroke by reducing the microglia-initiated proinflammatory response. Few studies, however, have focused on the phenotypic changes in microglia cells caused by exercise training. The present study was designed to evaluate the influence of treadmill exercise on microglia polarization and the molecular mechanisms involved. Methods: Male Sprague-Dawley rats were randomly assigned into 3 groups: sham, MCAO and exercise. The middle cerebral artery occlusion (MCAO) and exercise groups received MCAO surgery and the sham group a sham operation. The exercise group also underwent treadmill exercise after the surgery. These groups were studied after 4 and 7 days to evaluate behavioral performance using a modified neurological severity score (mNSS), and infarct conditions using 2,3,5-triphenyl tetrazolium chloride. Quantitative real-time polymerase chain reaction (qRT-PCR) and Luminex was employed to determine the expressions of markers of microglia phenotypes. Western blotting was employed to identify the phosphorylation levels of Janus kinase1 (JAK1) and signal transducer and activator of transcription 6 (STAT6). Immunofluorescence was conducted to identify microglia phenotypes. Results: Treadmill exercise was found to improve neurobehavioral outcomes, mainly motor and balance functions, reduce infarct volumes and significantly increase interleukin-4 (IL-4) expression. In addition, treadmill exercise inhibited M1 microglia and promoted M2 microglia activation as evidenced by decreased M1 and increased M2 markers. Furthermore, an obvious increase in p-JAK1 and p-STAT6 was observed in the exercise group. Conclusions: Treadmill exercise ameliorates cerebral ischemia-reperfusion injury by enhancing IL-4 expression to promote M2 microglia polarization, possibly via the JAK1-STAT6 pathway.

Agomelatine effects on fat-enriched diet induced neuroinflammation and depression-like behavior in rats

Growing evidence suggests that a high fat diet (HFD) induces oxidative stress on the central nervous system (CNS), which predisposes to mood disorders and neuroinflammation. In this study we postulated that in addition to improving mood, antidepressant therapy would reverse inflammatory changes in the brain of rats exposed to a HFD. To test our hypothesis, we measured the effect of the antidepressant agomelatine (AGO) on anxiety- and depressive-like behaviors, as well as on CNS markers of inflammation in rats rendered obese. Agomelatine is an agonist of the melatonin receptors MT1 and MT2 and an antagonist of the serotonin receptors 5HT2B and 5HT2C. A subset of rats was also treated with lipopolysaccharides (LPS) to determine how additional neuroinflammation alters behavior and affects the response to the antidepressant. Specifically, rats were subjected to a 14-week HFD, during which time behavior was evaluated twice, first at the 10th week prior to LPS and/or agomelatine, and then at the 14th week after a bi-weekly exposure to LPS (250 μg/kg) and daily treatment with agomelatine (40 mg/kg). Immediately after the second behavioral testing we measured the proinflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1 beta (IL-1β), markers of oxidative stress thiobarbituric acid reactive substances (TABRS), catalase (CAT) and glutathione peroxidase (GPx), the growth factor BDNF, as well as the apoptosis marker caspase-3. Our results show that a HFD induced an anxiety-like behavior in the open field test (OFT) at the 10th week, followed by a depressive-like behavior in the forced swim test (FST) at the 14th week. In the prefrontal and hippocampal cortices of rats exposed to a HFD we noted an overproduction of TNF-α, IL-6, IL-1β, and TABRS, together with an increase in caspase-3 activity. We also observed a decrease in BDNF, as well as reduced CAT and GPx activity in the same brain areas. Treatment with agomelatine reversed the signs of anxiety and depression, and decreased the cytokines (TNF-α, IL-6 and IL-1β), TABRS, as well as caspase-3 activity. Agomelatine also restored BDNF levels and the activity of antioxidant enzymes CAT and GPx. Our findings suggest that the anxiolytic/antidepressant effect of agomelatine in obese rats could result from a reversal of the inflammatory and oxidative stress brought about by their diet.

Differential protein input in the maternal diet alters the skeletal muscle transcriptome in fetal sheep

Maternal nutrition during pregnancy is one of the major intrauterine environmental factors that influence fetal development by significantly altering the expression of genes that might have a consequence on the physiological, morphological, and metabolic performance of the offspring in the postnatal period. The impact of maternal dietary protein on the expression of genes in sheep fetal skeletal muscle development is not well understood. The current study aims to investigate the impact of high and low maternal dietary protein on the holistic mRNA expression in the sheep fetal skeletal muscle. Dams were exposed to an isoenergetic high-protein diet (HP, 160-270 g/day), low-protein diet (LP, 73-112 g/day), and standard protein (SP, 119-198 g/day) diets during pregnancy. Fetal skeletal muscles were obtained at the 105th day of pregnancy and mRNA expression profiles were evaluated using Affymetrix GeneChip™ Ovine Gene 1.0 ST Array. The transcriptional analysis revealed a total of 323, 354, and 14 genes were differentially regulated (fold change > 2 and false discovery rate ≤ 0.05) in HP vs. SP, LP vs. HP, and SP vs. LP, respectively. Several myogenic genes, including MYOD1, MYH2, MYH1, are significantly upregulated, while genes related to the immune system, such as CXCL11, HLA-E, CXCL10, CXCL9, TLRs, are significantly downregulated in the fetal muscle of the HP group compared to those of SP and LP group. Bioinformatic analysis revealed that the majority of these genes are involved in pathways related to the immune system and diseases. The results of our study demonstrate that both augmented and restricted dietary proteins in maternal diet during pregnancy alter the expression of genes as well as the offspring's genetic marks.

Enduring effects of an unhealthy diet during adolescence on systemic but not neurobehavioural measures in adult rats

Introduction: Adolescence is an important stage of maturation for various brain structures. It is during this time therefore that the brain may be more vulnerable to environmental factors such as diet that may influence mood and memory. Diets high in fat and sugar (termed a cafeteria diet) during adolescence have been shown to negatively impact upon cognitive performance, which may be reversed by switching to a standard diet during adulthood. Consumption of a cafeteria diet increases both peripheral and central levels of interleukin-1β (IL-1β), a pro-inflammatory cytokine which is also implicated in cognitive impairment during the ageing process. It is unknown whether adolescent exposure to a cafeteria diet potentiates the negative effects of IL-1β on cognitive function during adulthood.Methods: Male Sprague-Dawley rats consumed a cafeteria diet during adolescence after which time they received a lentivirus injection in the hippocampus to induce chronic low-grade overexpression of IL-1β. After viral integration, metabolic parameters, circulating and central pro-inflammatory cytokine levels, and cognitive behaviours were assessed.Results: Our data demonstrate that rats fed the cafeteria diet exhibit metabolic dysregulations in adulthood, which were concomitant with low-grade peripheral and central inflammation. Overexpression of hippocampal IL-1β in adulthood impaired spatial working memory. However, adolescent exposure to a cafeteria diet, combined with or without hippocampal IL-1β in adulthood did not induce any lasting cognitive deficits when the diet was replaced with a standard diet in adulthood. Discussion: These data demonstrate that cafeteria diet consumption during adolescence induces metabolic and inflammatory changes, but not behavioural changes in adulthood.

Voluntary wheel running protects against the increase in ethanol consumption induced by social stress in mice

Previous studies have shown that exposure to social defeat (SD), a model of social stress, produces a long-term increase in the consumption of ethanol, most likely through an increase in the neuroinflammation response. The aim of the present study was to evaluate whether exposure to physical activity in the form of voluntary wheel running (VWR) could block the increase in ethanol consumption and the neuroinflammatory response induced by social stress. Mice were exposed to either 4 sessions of repeated social defeat (RSD) or a non-stressful experience. During the whole procedure, half of the mice were exposed to controlled physical activity, being allowed 1 h access to a low-profile running wheel three times a week. Three weeks after the last RSD, animals started the oral self-administration (SA) of ethanol (6% EtOH) procedure. Biological samples were taken 4 h after the first and the fourth RSD, 3 weeks after the last RSD, and after the SA procedure. Brain tissue (striatum) was used to determine protein levels of the chemokines fractalkine (CX3CL1) and SDF-1 (CXCL12). RSD induced an increase in ethanol consumption and caused greater motivation to obtain ethanol. The striatal levels of CX3CL1 and CXCL12 were also increased after the last RSD. VWR was able to reverse the increase in ethanol intake induced by social stress and the neuroinflammatory response. In conclusion, our results suggest that VWR could be a promising tool to prevent and reduce the detrimental effects induced by social stress.

Obesity Drives Delayed Infarct Expansion, Inflammation, and Distinct Gene Networks in a Mouse Stroke Model

Obesity is associated with chronic peripheral inflammation, is a risk factor for stroke, and causes increased infarct sizes. To characterize how obesity increases infarct size, we fed a high-fat diet to wild-type C57BL/6J mice for either 6 weeks or 15 weeks and then induced distal middle cerebral artery strokes. We found that infarct expansion happened late after stroke. There were no differences in cortical neuroinflammation (astrogliosis, microgliosis, or pro-inflammatory cytokines) either prior to or 10 h after stroke, and also no differences in stroke size at 10 h. However, by 3 days after stroke, animals fed a high-fat diet had a dramatic increase in microgliosis and astrogliosis that was associated with larger strokes and worsened functional recovery. RNA sequencing revealed a dramatic increase in inflammatory genes in the high-fat diet-fed animals 3 days after stroke that were not present prior to stroke. Genetic pathways unique to diet-induced obesity were primarily related to adaptive immunity, extracellular matrix components, cell migration, and vasculogenesis. The late appearance of neuroinflammation and infarct expansion indicates that there may be a therapeutic window between 10 and 36 h after stroke where inflammation and obesity-specific transcriptional programs could be targeted to improve outcomes in people with obesity and stroke.

Chronic psychosocial stress during pregnancy affects maternal behavior and neuroendocrine function and modulates hypothalamic CRH and nuclear steroid receptor expression

Postpartum depression (PPD) affects up to 20% of mothers and has negative consequences for both mother and child. Although exposure to psychosocial stress during pregnancy and abnormalities in the hypothalamic pituitary adrenal (HPA) axis have been linked to PPD, molecular changes in the brain that contribute to this disease remain unknown. This study utilized a novel chronic psychosocial stress paradigm during pregnancy (CGS) to investigate the effects of psychosocial stress on maternal behavior, neuroendocrine function, and gene expression changes in molecular regulators of the HPA axis in the early postpartum period. Postpartum female mice exposed to CGS display abnormalities in maternal behavior, including fragmented and erratic maternal care patterns, and the emergence of depression and anxiety-like phenotypes. Dysregulation in postpartum HPA axis function, evidenced by blunted circadian peak and elevation of stress-induced corticosterone levels, was accompanied by increased CRH mRNA expression and a reduction in CRH receptor 1 in the paraventricular nucleus of the hypothalamus (PVN). We further observed decreased PVN expression of nuclear steroid hormone receptors associated with CRH transcription, suggesting these molecular changes could underlie abnormalities in postpartum HPA axis and behavior observed. Overall, our study demonstrates that psychosocial stress during pregnancy induces changes in neuroendocrine function and maternal behavior in the early postpartum period and introduces our CGS paradigm as a viable model that can be used to further dissect the molecular defects that lead to PPD.

Balanophora polyandra Griff. prevents dextran sulfate sodium-induced murine experimental colitis via the regulation of NF-κB and NLRP3 inflammasome

Balanophora polyandra Griff. (B. polyandra) is a folk medicine used as an antipyretic, antidote, haemostatic, dressing and haematic tonic, for the treatment of gonorrhea, syphilis, wounds, and the bleeding of the alimentary tract by the local people in China.

Aerobic Exercise Ameliorates Myocardial Inflammation, Fibrosis and Apoptosis in High-Fat-Diet Rats by Inhibiting P2X7 Purinergic Receptors

Background

High-fat-diet (HFD) is associated with chronic low-grade inflammation. P2X7 purinergic receptors (P2X7R) are key regulators of inflammasome activation. The benefits of exercise are partly attributed to its anti-inflammatory effect, but whether it regulates P2X7R expression to improve remodeling in cardiac myocytes treated by HFD is not completely clarified.

Methods

Three groups of Sprague-Dawley (SD) rats were studied: (1) control group (fed a normal chow diet), (2) HFD group, and (3) HFD+ exercise group. H9c2 myocytes were pretreated with or without A438079 (a P2X7R inhibitor) and then exposed to 200 μM palmitic acid (PA) for 24 h. The levels of mRNA and protein were measured by real-time PCR and Western blot, respectively. Masson staining and hematoxylin-eosin (HE) staining were used to identify remodeling of the heart. The concentration of IL-1β in serum or supernatants were measured by ELISA.

Results

In vivo, collagen deposition and the number of disordered cells significantly increased in the hearts of the HFD group compared to the control group. However, exercise markedly reversed these changes in the myocardium, and the same trends were observed in the expression of MMP9, collagen I and TGF-β. Notably, the expression of P2X7R, NLRP3, caspase-1 in the hearts, and serum IL-1β level were also greatly upregulated in the heart of the HFD diet rats, and all these changes were ameliorated in the HFD + EX group. As expected, exercise also reduced the number of TUNEL-positive cells, which was consistent with the caspase-3, Bax, and Bcl-2 results. Moreover, exercise reduced body weight and blood lipid concentrations in the HFD diet rats. In vitro, we observed that the hallmark of fibrosis, inflammation and apoptosis in H9c2 myocytes enhanced by PA, and the P2X7R inhibitor treatment significantly reduced the expression of the NLRP3, caspase-1, suppressed the secretion of IL-1β of H9c2 cells, inhibited collagen I, TGF-β, MMP9, Bax, caspase-3 levels and increased the expression of Bcl-2, compared with the PA group. In addition, a decrease of the number of TUNEL-positive cells used by A438079 further support that cardiomyocytes apoptosis could be inhibited.

Conclusion

Aerobic exercise reversed the cardiac remodeling via the reduction of inflammation, fibrosis and apoptosis in HFD rats, at least in part through inhibiting P2X7R expression in cardiomyocytes.

The role of inflammation and endoplasmic reticulum stress in obesity-related cognitive impairment

The epidemiological investigations and animal model experiments have confirmed the impact of obesity on the brain, behavior, and cognition. However, the mechanism by which obesity affects cognitive function is not fully understood. With the development of an aging society, there is an increase in the economic and social burden caused by the decline in cognitive function. This manuscript reviews the effects of inflammation and endoplasmic reticulum stress (ERS) on the hypothalamus, hippocampus, and the possible impact on cognitive impairment. These findings provide new insights into the pathophysiological mechanisms that lead to the development of cognitive impairment in the context of obesity.

Physical Exercise Inhibits Inflammation and Microglial Activation

Accumulating evidence indicates that exercise can enhance brain function and attenuate neurodegeneration. Besides improving neuroplasticity by altering the synaptic structure and function in various brain regions, exercise also modulates multiple systems that are known to regulate neuroinflammation and glial activation. Activated microglia and several pro-inflammatory cytokines play active roles in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease. The purpose of this review is to highlight the impacts of exercise on microglial activation. Possible mechanisms involved in exercise-modulated microglial activation are also discussed. Undoubtedly, more studies are needed in order to disclose the detailed mechanisms, but this approach offers therapeutic potential for improving the brain health of millions of aging people where pharmacological intervention has failed.

Suboptimal nutrition in early life affects the inflammatory gene expression profile and behavioral responses to stressors

Nutritional conditions in early life can have a lasting impact on health and disease risk, though the underlying mechanisms are incompletely understood. In the healthy individual, physiological and behavioral responses to stress are coordinated in such a way as to mobilize resources necessary to respond to the stressor and to terminate the stress response at the appropriate time. Induction of proinflammatory gene expression within the brain is one such example that is initiated in response to both physiological and psychological stressors, and is the focus of the current study. We tested the hypothesis that early life nutrition would impact the proinflammatory transcriptional response to a stressor. Pregnant and lactating dams were fed one of three diets; a low-protein diet, a high fat diet, or the control diet through pregnancy and lactation. Adult male offspring were then challenged with either a physiological stressor (acute lipopolysaccharide injection, IP) or a psychological stressor (15 min restraint). Expression of 20 proinflammatory and stress-related genes was evaluated in hypothalamus, prefrontal cortex, amygdala and ventral tegmental area. In a second cohort, behavioral responses (food intake, locomotor activity, metabolic rate) were evaluated. Offspring from low protein fed dams showed a generally reduced transcriptional response, particularly to LPS, and resistance to behavioral changes associated with restraint, while HF offspring showed an exacerbated transcriptional response within the PFC, a reduced transcriptional response in hypothalamus and amygdala, and an exacerbation of the LPS-induced reduction of locomotor activity. The present data identify differential proinflammatory transcriptional responses throughout the brain driven by perinatal diet as an important variable that may affect risk or resilience to stressors.

Reversal of high fat diet-induced obesity improves glucose tolerance, inflammatory response, β-amyloid accumulation and cognitive decline in the APP/PSEN1 mouse model of Alzheimer's disease

This study assessed the extent to which high fat diet (HFD)-induced β-amyloid accumulation and cognitive decline in APP/PSEN1 mice are reversible through control of fat intake. Ten months of HFD (60% calories from fat) led to significant deficits in a 2-trial Y maze task, and nest building assay, and decreased voluntary locomotor activity. The HFD induced an inflammatory response, indicated by increased expression of several inflammatory markers. Substituting a low fat diet led to pronounced weight loss and correction of glucose intolerance, decreases in the inflammatory response, and improved performance on behavioral tasks in both wild-type and APP/PSEN1 transgenic mice. Insoluble β-amyloid levels, and extent of tau phosphorylation were also lower following dietary reversal in APP/PSEN1 mice compared to high fat-fed animals, indicating that the inflammatory response may have contributed to key pathogenic pathways in the Alzheimer's disease model. The data suggest that weight loss can be a vital strategy for cognitive protection, but also highlight potential mechanisms for intervention when sustained weight loss is not possible.