Role of spleen-derived IL-10 in prevention of systemic low-grade inflammation by obesity [Review]

Kidney injury: the spleno-renal connection and splenic tyrosine kinase

Kidney injury is a major medical burden and one of the most common reasons for hospitalization and poor life quality. Kidney injury can include acute kidney injury, chronic kidney disease, and immune-mediated kidney diseases most of which have no definitive therapy. The spleen is a secondary lymphoid organ in the reticuloendothelial system that plays an important role in protecting the body from various diseases. Notably, spleen tyrosine kinase, a non-receptor tyrosine kinase, is a crucial player that aids in immunity and protection and is highly expressed in the kidney and hematopoietic cells. It has been shown that alterations in spleen tyrosine kinase function or expression could lead to a wide range of diseases and abnormalities. Over the past decade, the role of spleen and spleen tyrosine kinase in multiple kidney diseases has emerged. Evidence suggests that modulating the spleno-renal connection through activation of the cholinergic anti-inflammatory pathway can be a promising strategy for protecting against kidney injury. Imitating the protective function of the spleen through interleukin-10-extracellular vesicles can also be of therapeutic value. In addition, evidence showed that inhibition of the spleen tyrosine kinase leads to amelioration of the kidney injury. However, further exploration and long-term studies are needed to unravel the spleno-renal connection, as well as the efficacy of spleen tyrosine kinase inhibitors, before they can be used as means for treatment of kidney injury.

Metabolic Recovery with the Persistence of Proinflammatory Leucocyte Dysfunction After Bariatric Intervention for Obesity

PURPOSE

A suitable option for severe obesity treatment is a surgical approach. After surgery, metabolic markers and weight frequently return to adequate values; however, concerning systemic inflammatory mediators, the results are inconsistent. Furthermore, it has been suggested that leucocyte function may be affected even after weight normalization. This study aimed to determine if the surgical treatment of obesity influences the production of cytokines by LPS-stimulated as a function of leucocytes.

MATERIALS AND METHODS

We performed a cross-sectional study that investigated the production of cytokines in response to lipopolysaccharide (LPS) along a kinetic of simulation by leucocytes recovered from individuals with normal weight (NW, n = 8), persons living with obesity (Ob, n = 7), persons living with obesity and diabetes mellitus (Ob-DM, n = 17), and persons that used to live with obesity who underwent bypass surgery (fOb + bypass, n = 8) and recover normal weigh.

RESULTS

IL-6 levels were significantly higher in the Ob and fOb + bypass groups than in NW (p = 0.043). IL-10 secretion without LPS was significantly higher in the NW group than in the other groups explored (p < 0.05). When exposed to LPS, the IL-10 levels increased in all groups except the NW group. As also observed for IL-18 and IL-33, the secretion curve of the fOb + bypass group was more similar to the Ob group, even when they had reached normal weight, as opposed to the NW group.

CONCLUSION

Our results show that in patients with fOb + bypass, inflammatory and anti-inflammatory cytokine production dynamics remain disrupted even with improved metabolic control and normal weight recovery.

Interleukin-10 is not associated with obstructive sleep apnea hypopnea syndrome: A meta-analysis and meta-regression

BACKGROUND

This study was conducted to explore the potential relationship between interleukin-10 (IL-10) and obstructive sleep apnea hypopnea syndrome (OSAHS).

METHODS

All the related research articles published before October 2022 were retrieved through the online database (EMBASE, VIP, Wan Fang, Web of Science, PubMed, and CNKI). Stata 11.0 software was used to calculate the standard mean difference (SMD) of the continuous variable and 95% confidence interval (CI). Expression profiles GSE38792 and GSE135917 were acquired from Gene Expression Omnibus (GEO) database, respectively. The expression of IL-10 mRNA in subcutaneous adipose tissue and visceral adipose tissue of OSAHS patients and healthy subjects was extracted by R software to verify the difference in IL-10 between the 2 groups.

RESULTS

The IL-10 level in the plasma of people with and without OSAHS (STD Mean Difference (SMD) = -0.68, 95% CI = -1.58 to 0.21, I2 = 94.3%, P = .136) was the same. There was also no difference in IL-10 levels in serum between people with and without OSAHS (SMD = -0.12, 95% CI = -0.55 to 0.32, I2 = 94.4%, P = .591). In addition, the subjects were divided into different subgroups for meta-analysis according to race, body mass index, age, study type, and disease severity. Based on the outcomes, no notable difference was observed in the plasma/serum IL-10 level between the OSAHS subgroups and the control group. The results of bioinformatics analysis indicated that there was no significant difference in the expression of IL-10 mRNA in subcutaneous adipose tissue and visceral adipose tissue between patients with OSAHS and those in the control group.

CONCLUSION

The current meta-analysis highlighted that IL-10 levels between patients with OSAHS and healthy people had no difference.

Association between cytokine levels and anthropometric measurements: a population-based study

Obesity is currently considered a public health problem with pandemic proportions and is associated with chronic low-grade inflammation, which can predispose to the development of several chronic diseases and metabolic complications. This cross-sectional population-based study, conducted with 743 Brazilian adults, aimed to evaluate the association between inflammatory cytokines with anthropometric measurements. Socio-demographic, anthropometric, behavioural and biochemical variables were collected. Multiple linear regression stratified by sex and adjusted for confounding factors was performed. In men, waist circumference (WC) was associated with IL-1β (3·52 pg/ml; 95 % CI 0·60, 6·45), IL-6 (6·35 pg/ml; 95 % CI 0·35, 12·34), IL-8 (8·77 pg/ml; 95 % CI 2·37, 15·17), IL-10 (3·09 pg/ml; 95 % CI 0·56, 5·61), IL12p70 (8·31 pg/ml; 95 % CI 3·11, 13·52) and TNF-α (4·22 pg/ml; 95 % CI 0·20, 10·48). Waist:height ratio was associated with IL-6 (3·21 pg/ml; 95 % CI 0·02, 6·39). BMI was associated with IL-1β (1·50 pg/ml; 95 % CI 0·46, 2·34), IL-6 (2·97 pg/ml; 95 % CI 0·78, 5·16), IL-8 (4·48 pg/ml; 95 % CI 2·21, 6·75), IL-10 (1·31 pg/ml; 95 % CI 0·30, 2·31), IL-12p70 (3·59 pg/ml; 95 % CI 1·24, 5·95) and TNF-α (2·00 pg/ml; 95 % CI 0·81, 3·19). In women, WC was associated with IL-6 (5·10 pg/ml; 95 % CI 0·68, 9·51) and IL-10 (4·16 pg/ml; 95 % CI 1·26, 7·06). BMI was associated with IL-6 (2·67 pg/ml; 95 % CI 0·34, 4·99), and WHR was associated with TNF-α (2·84 pg/ml; 95 % IC 0·86-6·54). The results highlight the importance of anthropometric assessment in clinical practice and the need to develop public policies and interventions to reduce the prevalence of obesity and, consequently, of inflammation and possible metabolic complications.

Leptin Increases: Physiological Roles in the Control of Sympathetic Nerve Activity, Energy Balance, and the Hypothalamic-Pituitary-Thyroid Axis

It is well established that decreases in plasma leptin levels, as with fasting, signal starvation and elicit appropriate physiological responses, such as increasing the drive to eat and decreasing energy expenditure. These responses are mediated largely by suppression of the actions of leptin in the hypothalamus, most notably on arcuate nucleus (ArcN) orexigenic neuropeptide Y neurons and anorexic pro-opiomelanocortin neurons. However, the question addressed in this review is whether the effects of increased leptin levels are also significant on the long-term control of energy balance, despite conventional wisdom to the contrary. We focus on leptin's actions (in both lean and obese individuals) to decrease food intake, increase sympathetic nerve activity, and support the hypothalamic-pituitary-thyroid axis, with particular attention to sex differences. We also elaborate on obesity-induced inflammation and its role in the altered actions of leptin during obesity.

Heme induces inflammatory injury by directly binding to the complex of myeloid differentiation protein 2 and toll-like receptor 4

Heme, as an essential component of hemoproteins, is a prosthetic co-factor found in many cells, which is essential for physiologically vital oxygen transport. However, extracellular or circulatory heme is cytotoxic and triggers inflammation. Although the proinflammatory role of heme has been reported to be associated with Toll-like receptor 4 (TLR4) signaling, the exact mechanism remains unknown. Here, we show that heme promotes TLR4 signaling and inflammation via directly physically interacting with TLR4 and its adaptor protein myeloid differentiation protein 2 (MD2). Genetic loss of MD2 ameliorates heme-induced inflammation and inflammatory cytokine production in the spleen of MD2 knockout (MD2^-/-) mice. Using mouse macrophage RAW 264.7 cell line, we show that heme induces TLR4 dimerization and MD2/TLR4/MyD88 activation by physically interacting with TLR4 and MD2 in vitro. Genetic loss of MD2 inhibits heme-induced inflammation and MAPK/NF-κB pathway in mouse primary macrophages extracted from MD2^-/- mice. Furthermore, pharmacological inhibition of MD2 by L6H9 ameliorates heme-induced inflammation in macrophages. These findings demonstrate that heme causes inflammation by directly binding to MD2/TLR4 complex, leading to activation of TLR4/MAPK/NF-κB signaling pathway and production of downstream effectors of inflammation.

Interleukins and redox impairment in type 2 diabetes mellitus: mini-review and pilot study

BACKGROUND

Type 2 diabetes mellitus (T2DM) represents a leading cause of morbidity and premature mortality, low-grade inflammation being acknowledged as a key contributor to its development and progression. A tailored therapeutic approach, based on sensitive and specific biomarkers, could allow a more accurate analysis of disease susceptibility/prognostic and of the response to treatment.

OBJECTIVES

This mini-review and pilot study had two main goals: (1) reviewing the most recent literature encompassing the use of interleukins as inflammatory markers influenced by the redox imbalances in T2DM and (2) assessing parameters that conjunctly evaluate the redox impairment and inflammatory burden of T2DM patients, taking into consideration smoking status, as such group-specific biomarkers are scarcely reported in literature.

METHODS

Firstly, PubMed database was surveyed to select and review the relevant studies employing interleukins as T2DM biomarkers and to assess if studies using combined inflammatory-redox indices were reported. Then, routine biochemical parameters were assessed in a pilot study -T2DM patients with 3 subgroups: non-smokers, smokers and ex-smokers, were compared to a control group of non-diabetic, apparently healthy non-smokers. Protein (AOPPs, AGEs), lipid/HDL (Amplex Red-based method) oxidative damage and inflammatory status (CRP, IL-1β, IL-6, IL-10) biomarkers were assessed. Cytokine ratios and 2 oxidative-inflammatory status indices were developed (IH1 and IH2) and evaluated.

RESULTS

We observed significant differences in terms of serum redox and inflammatory status (AOPPs, AGEs, CRP, CRP/HDL, CRP/IL-6, IL-10/IL-6, IH1) between T2DM patients compared to control and, moreover, between the subgroups formed considering smoking status (CRP, CRP/HDL, IH1). Glycemic control strongly influenced inflammatory status biomarkers: glycemia was positively correlated with the inflammatory parameters (CRP/IL-10) and inversely with the anti-inflammatory ones (IL-10, IL-10/IL-1β ratio).

CONCLUSIONS

Several of the assessed parameters may possess prognostic value for diabetics, especially when comparing subgroups with a different smoking history and could prove useful in clinical practice for assessing disease progress and therapeutic efficacy.

Human umbilical cord-derived mesenchymal stem cells alleviate insulin resistance in diet-induced obese mice via an interaction with splenocytes

Background

Previous research has demonstrated that the spleen plays an important role in mesenchymal stem cell (MSC)-mediated alleviation of acute inflammation, as MSC infusion increases the spleen-derived anti-inflammatory cytokine interleukin 10 (IL-10) levels. However, studies on splenic involvement in MSC-induced protection against chronic inflammatory diseases are limited. Obesity is characterized by chronic low-grade inflammation, a key driver of insulin resistance. This study aims to evaluate the effects of MSCs on obesity-related insulin resistance and explore the underlying mechanism, particularly regarding splenic involvement.

Methods

We induced obesity in mice by feeding them high-fat diets for 20 weeks. Human umbilical cord-derived MSCs (UC-MSCs) were systemically infused into the obese mice once per week for 6 weeks. Systemic glucose metabolic homeostasis and insulin sensitivity in epididymal adipose tissue (EAT) were evaluated. Then, we conducted in vivo blockade of IL-10 during UC-MSC infusion by intraperitoneally administrating an IL-10-neutralizing antibody twice per week. We also investigated the therapeutic effects of UC-MSCs on obese mice after removal of the spleen by splenectomy.

Results

UC-MSC infusions improved systemic metabolic homeostasis and alleviated insulin resistance in EAT but elicited no change in weight. Despite rare engraftment of UC-MSCs in EAT, UC-MSC infusions attenuated insulin resistance in EAT by polarizing macrophages into the M2 phenotype, coupled with elevated serum IL-10 levels. In vivo blockade of IL-10 blunted the effects of UC-MSCs on obese mice. Furthermore, UC-MSCs overwhelmingly homed to the spleen, and the ability of UC-MSCs to elevate serum IL-10 levels and alleviate insulin resistance was impaired in the absence of the spleen. Further in vivo and in vitro studies revealed that UC-MSCs promoted the capacity of regulatory T cells (Treg cells) to produce IL-10 in the spleen.

Conclusions

Our results demonstrated that UC-MSCs elevated serum IL-10 levels and subsequently promoted macrophage polarization, leading to alleviation of insulin resistance in EAT. The underlying mechanism was that UC-MSCs improved the capacity of Treg cells to produce IL-10 in the spleen. Our findings indicated that the spleen played a critical role in amplifying MSC-mediated immunomodulatory effects, which may contribute to maximizing MSC efficacy in clinical applications in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02791-6.

Therapeutic Effects of Bee Bread on Obesity-Induced Testicular-Derived Oxidative Stress, Inflammation, and Apoptosis in High-Fat Diet Obese Rat Model

Obesity is a debilitating disorder with a variety of problems including oxidative stress, inflammation, and apoptosis. The aim of our study was to investigate the therapeutic role of bee bread on oxidative stress, apoptosis, and inflammation in the testis of obese rats. Thirty-two adult male Sprague Dawley rats, with weights between 230–300 g, were distributed into four groups (n = 8/group), namely normal control (C), obese (Ob), obese + BB or obese + OR [high-fat diet (HFD) for 6 weeks then HFD plus bee bread or orlistat for another 6 weeks] groups. Bee bread (0.5 g/kg) or orlistat (10 mg/kg/day) was diluted with distilled water and administered daily for 6 weeks by oral gavage. There were significant decreases in the activities of antioxidant enzymes [glutathione-S-transferase (GST), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR)], glutathione (GSH)] and total antioxidant capacity (TAC) levels and mRNA expressions of nuclear factor erythroid 2–related factor 2 (Nrf2), superoxide dismutase (Sod), catalase (Cat) and glutathione peroxidase (Gpx) in the obese group relative to the control group. Meanwhile, the mRNA levels of pro-inflammatory markers, namely: inducible nitric oxide synthase (Inos), nuclear factor kappa B (Nf-κβ), tumour necrotic factor α (Tnf-α) and interleukin 1β (Il-1β) were significantly increased while interleukin (Il-10) was decreased in the obese group relative to the control group. Further, proliferating cell nuclear antigen (PCNA) immunoexpressions decreased while cleaved caspase-3 immunohistochemical staining increased significantly in the obese group, in addition to increases in the mRNA levels of p53, Bax, Caspases-8, 9 and 3, relative to the control group. Treatment with bee bread showed increases in antioxidant enzymes and PCNA immunoexpression, as well as decreases in inflammation and apoptosis markers in the testes. This study has shown that bee bread has therapeutic effects against oxidative stress, inflammation, apoptosis in the testis of HFD-induced obese male rats, thereby suggesting its role as a natural supplement capable of treating obesity-induced male reproductive impairment.

Metabolomics Based on 1H-NMR Reveal the Regulatory Mechanisms of Dietary Methionine Restriction on Splenic Metabolic Dysfunction in Obese Mice

Methionine restriction (MR) has been reported to have many beneficial health effects, including stress resistance enhancement and lifespan extension. However, the effects of MR on the splenic metabolic dysfunction induced by obesity in mice remain unknown. This study aimed to investigate the scientific problem and clarify its possible mechanisms. C57BL/6J mice in the control group were fed a control diet (0.86% methionine, 4.2% fat) for 34 weeks, and others were fed a high-fat diet (0.86% methionine, 24% fat) for 10 weeks to establish diet-induced obese (DIO) mouse models. Then, the obtained DIO mice were randomly divided into two groups: the DIO group (DIO diet), the DIO + MR group (0.17% methionine, 24% fat) for 24 weeks. Our results indicated that MR decreased spleen weight, and spleen and plasma lipid profiles, promoted lipid catabolism and fatty acid oxidation, glycolysis and tricarboxylic acid cycle metabolism, and improved mitochondrial function and ATP generation in the spleen. Moreover, MR normalized the splenic redox state and inflammation-related metabolite levels, and increased plasma levels of immunoglobulins. Furthermore, MR increased percent lean mass and splenic crude protein levels, activated the autophagy pathway and elevated nucleotide synthesis to maintain protein synthesis in the spleen. These findings indicate that MR can ameliorate metabolic dysfunction by reducing lipid accumulation, oxidative stress, and inflammation in the spleen, and the mechanism may be the activation of autophagy pathway.

Anti-inflammatory effects of oleic acid and the anthocyanin keracyanin alone and in combination: effects on monocyte and macrophage responses and the NF-κB pathway

Monocyte recruitment and activation of macrophages are essential for homeostasis but are also related to the development and progression of cardiometabolic diseases. The management of inflammation with dietary components has been widely investigated. Two components that may influence inflammation are unsaturated fatty acids such as oleic acid (OA; 18:1cis-9) and antioxidant compounds like anthocyanins. Molecular and metabolic effects of such bioactive compounds are usually investigated in isolation, whereas they may be present in combination in foods or the diet. Considering this, we aimed to analyze the effects of OA and the anthocyanin keracyanin (AC) alone and in combination on toll-like receptor-mediated inflammatory responses in monocytes and macrophages. For this, THP-1-derived macrophages and monocytes were exposed to 3 treatments: OA, AC, or the combination (OAAC) and then stimulated with lipopolysaccharide. Inflammation-related gene expression and protein concentrations of IL-1β, TNF-α, IL-6, MCP-1, and IL-10 were assessed. Also, NFκBp65, IκBα, and PPAR-γ protein expression were determined. OA, AC, and OAAC decreased pNFκBp65, PPARγ, IκBα, TNF-α, IL-1β, IL-6, and MCP-1 and increased IL-10. MCP-1 protein expression was lower with OAAC than with either OA and AC alone. Compared to control, OAAC decreased mRNA for TLR4, IκKα, IκBα, NFκB1, MCP-1, TNF-α, IL-6, and IL-1β more than OA or AC did alone. Also, IL-10 mRNA was increased by OAAC compared with control, OA, and AC. In summary, OA and AC have anti-inflammatory effects individually but their combination (OAAC) exerts a greater effect.

The Vagus Nerve and Spleen: Influence on White Adipose Mass and Histology of Obese and Non-obese Rats

The vagus nerve (VN) and spleen represent a complex interface between neural and immunological functions, affecting both energy metabolism and white adipose tissue (WAT) content. Here, we evaluated whether vagal and splenic axis participates in WAT mass regulation in obese and non-obese male Wistar rats. High doses of monosodium glutamate (M; 4 g/Kg) were administered during the neonatal period to induce hypothalamic lesion and obesity (M-Obese rats). Non-obese or Control (CTL) rats received equimolar saline. At 60 days of life, M-Obese and CTL rats were randomly distributed into experimental subgroups according to the following surgical procedures: sham, subdiaphragmatic vagotomy (SV), splenectomy (SPL), and SV + SPL (n = 11 rats/group). At 150 days of life and after 12 h of fasting, rats were euthanized, blood was collected, and the plasma levels of glucose, triglycerides, cholesterol, insulin, and interleukin 10 (IL10) were analyzed. The visceral and subcutaneous WAT depots were excised, weighed, and histologically evaluated for number and size of adipocytes as well as IL10 protein expression. M-Obese rats showed higher adiposity, hyperinsulinemia, hypertriglyceridemia, and insulin resistance when compared with CTL groups (p < 0.05). In CTL and M-Obese rats, SV reduced body weight gain and triglycerides levels, diminishing adipocyte size without changes in IL10 expression in WAT (p< 0.05). The SV procedure resulted in high IL10 plasma levels in CTL rats, but not in the M-Obese group. The splenectomy prevented the SV anti-adiposity effects, as well as blocked the elevation of IL10 levels in plasma of CTL rats. In contrast, neither SV nor SPL surgeries modified the plasma levels of IL10 and IL10 protein expression in WAT from M-Obese rats. In conclusion, vagotomy promotes body weight and adiposity reduction, elevating IL10 plasma levels in non-obese animals, in a spleen-dependent manner. Under hypothalamic obesity conditions, VN ablation also reduces body weight gain and adiposity, improving insulin sensitivity without changes in IL10 protein expression in WAT or IL10 plasma levels, in a spleen-independent manner. Our findings indicate that the vagal-spleen axis influence the WAT mass in a health state, while this mechanism seems to be disturbed in hypothalamic obese animals.

Characterization of a lignin from Crataeva tapia leaves and potential applications in medicinal and cosmetic formulations

Lignins are phenolic macromolecules that have several applications. In this work, we examine some biological activities of a lignin-like macromolecule isolated from the Crataeva tapia leaves, not yet studied to evaluate its potential applications in medicinal and cosmetic formulations. Lignin was obtained by alkaline delignification and its physical-chemical characterization was made by means of FT-IR, UV-Vis, NMR spectroscopy, elementary analysis, molecular mass determination and thermal analysis. Lignin is of the GSH type, with levels of hydrogen (5.10%), oxygen (27.18%), carbon (67.60%), nitrogen (0.12%) and phenolic content of 189.6 ± 9.6 mg GAE/g. In addition, it is a thermally stable macromolecule with low antioxidant activity. Cytotoxicity and cytokine production were assessed by flow cytometry. The photoprotective activity was evaluated by adding different concentrations of lignin to a commercial cream. Lignin was not cytotoxic, it stimulated the production of TNF-α, IL-6 and IL-10 and did not promote a significant change in nitric oxide levels. In addition, this macromolecule was able to promote increased absorption of ultraviolet light from a commercial cream. These results reinforce the ethnopharmacological use of C. tapia leaves and suggest the need for further studies to determine the potential medicinal and cosmetic applications (sunscreen) of lignin from C. tapia leaves.

Glucose as a Major Antioxidant: When, What for and Why It Fails?

A human organism depends on stable glucose blood levels in order to maintain its metabolic needs. Glucose is considered to be the most important energy source, and glycolysis is postulated as a backbone pathway. However, when the glucose supply is limited, ketone bodies and amino acids can be used to produce enough ATP. In contrast, for the functioning of the pentose phosphate pathway (PPP) glucose is essential and cannot be substituted by other metabolites. The PPP generates and maintains the levels of nicotinamide adenine dinucleotide phosphate (NADPH) needed for the reduction in oxidized glutathione and protein thiols, the synthesis of lipids and DNA as well as for xenobiotic detoxification, regulatory redox signaling and counteracting infections. The flux of glucose into a PPP—particularly under extreme oxidative and toxic challenges—is critical for survival, whereas the glycolytic pathway is primarily activated when glucose is abundant, and there is lack of NADP⁺ that is required for the activation of glucose-6 phosphate dehydrogenase. An important role of glycogen stores in resistance to oxidative challenges is discussed. Current evidences explain the disruptive metabolic effects and detrimental health consequences of chronic nutritional carbohydrate overload, and provide new insights into the positive metabolic effects of intermittent fasting, caloric restriction, exercise, and ketogenic diet through modulation of redox homeostasis.

A dose-response evaluation of purified anthocyanins on inflammatory and oxidative biomarkers and metabolic risk factors in healthy young adults: A randomized controlled trial

OBJECTIVES

Anthocyanins derived from different plant sources have been found to possess a variety of health-promoting effects, including antiinflammatory properties and protection from oxidative stress. The aim of this study was to investigate the dose-response relationship between anthocyanins and metabolic risk factors as well as inflammatory and oxidative biomarkers in healthy adult volunteers.

METHODS

We conducted a randomized, double-blind, placebo-controlled trial, which included an increasing dosing schedule of 20, 40, 80, 160, and 320 mg of purified anthocyanins or placebo. Participants (n = 111) were administered either agent for 14 consecutive days.

RESULTS

No significant differences in either baseline characteristics or daily intake of dietary nutrients were detected between the experimental and control groups. After anthocyanin supplementation, there was a significant difference in adjusted fasting plasma glucose levels. The group receiving 80 mg/d of anthocyanin had the lowest baseline-adjusted fasting plasma glucose when compared with placebo (F = 3.556, P = 0.007). Logarithmically adjusted plasma interleukin-10 levels were negatively correlated with increasing anthocyanin dose (F = 2.738, P = 0.025). Similarly, 8-iso-prostaglandin F2α levels decreased with increasing anthocyanins dose (F = 3.513, P = 0.009).

CONCLUSIONS

Taken together, our results suggest that anthocyanin supplementation at a dose greater than 80 mg/d is an effective antioxidant and antiinflammatory agent in healthy young adults.

Plasma from remotely conditioned pigs reduces infarct size when given before or after ischemia to isolated perfused rat hearts

Short cycles of ischemia/reperfusion in a tissue/organ remote from the heart reduce myocardial ischemia/reperfusion injury. Such remote ischemic conditioning (RIC) can be induced before (pre-), during (per-), or after (post-) the onset of myocardial ischemia. RIC's protection can be transferred with plasma between different individuals, even across species. Infusion of plasma from pigs with remote ischemic per-conditioning(RPERC) reduces infarct size in isolated perfused rat hearts when given before and after the index ischemia. We here determined whether or not infusion of pig plasma is equally protective when given exclusively before or after the index ischemia in isolated perfused rat hearts. Blood was sampled at 10 min reperfusion from Göttingen mini-pigs with 60/180 min coronary occlusion/reperfusion without (placebo, n = 8) or with RPERC (4 × 5 min/5 min hindlimb ischemia/reperfusion, n = 7) starting at 20 min coronary occlusion. Plasma was separated, diluted (1:6), and infused into isolated perfused rat hearts before (plasma_before) or after (plasma_after) 30/120 min global zero-flow ischemia/reperfusion. Infarct size (IS) was demarcated and calculated as percent of ventricular mass (means ± standard deviations). The activation of cardioprotective intracellular signaling cascades was analyzed by Western blot. RPERC-plasma reduced IS (placebo-plasma_before 36 ± 5% and placebo-plasma_after 36 ± 7% versus RPERC-plasma_before 19 ± 3% and RPERC-plasma_after 21 ± 4%; P < 0.001 versus placebo-plasma) and increased the phosphorylation of signal transducer and activator of transcription 3, no matter whether plasma was given before ischemia or during reperfusion. Obviously, the protection, which the released factors exert, is operative during reperfusion. However, pre-ischemic exposure to such cardioprotective factors is remembered throughout ischemia.

Post-natal Growth Retardation Associated With Impaired Gut Hormone Profiles, Immune and Antioxidant Function in Pigs

The factors that cause post-natal growth retardation (PGR) in pigs are complicated; however, metabolic and immune system impairment seem to be involved. The purpose of this study was to investigate the changes of blood parameters, hormone profiles, antioxidant capacity, and immune responses in PGR pigs. Blood and small intestinal mucosa samples were collected from 42-days-old PGR and healthy pigs. The results showed that compared with the healthy group, the relative weight of spleen and kidney were greater, but the liver was lighter in PGR pigs (P < 0.05). The PGR pigs had increased serum alanine transaminase, urea nitrogen, blood ammonia, IgG, and complement 4, but decreased glucose and albumin (P < 0.05). The higher levels of serum leptin (LEP) and thyroxin (T4), and the lower levels of insulin-like growth factor-1 (IGF-1), 5-hydroxytryptamine (5-HT), somatostatin (SS), and agouti gene-related protein (AgRP) were observed in PGR pigs (P < 0.05). Consistent with the serum levels of hormones, the mRNA levels of gut hormones and their receptors were also altered in intestinal mucosa from PGR pigs (P < 0.05). The PGR pigs exhibited higher plasma concentrations of interleukin-1β (IL-1β), IL-6, IL-8, and transformed growth factor beta (TGFβ) (P < 0.05). However, the mRNA expressions of several cytokines were lower in the small intestinal mucosa of PGR pigs (P < 0.05). Abnormal antioxidant indexes in serum of PGR pigs were observed, which was in accordance with the reduced mRNA expression of several anti-oxidative genes in the small intestinal mucosa of PGR pigs (P < 0.05). These data demonstrate that an abnormal gut hormone system, immune dysfunction, and decreased antioxidant capacity may contribute to PGR in pigs. These changes could provide a valuable target in the regulation of post-natal growth retardation in animals and humans.

Vago-Splenic Axis in Signal Transduction of Remote Ischemic Preconditioning in Pigs and Rats

RATIONALE

The signal transduction of remote ischemic conditioning is still largely unknown.

OBJECTIVE

Characterization of neurohumoral signal transfer and vago-splenic axis in remote ischemic preconditioning (RIPC).

METHODS AND RESULTS

Anesthetized pigs were subjected to 60 minutes of coronary occlusion and 180 minutes of reperfusion (placebo+ischemia/reperfusion [PLA+I/R]). RIPC was induced by 4×5/5 minutes of hindlimb I/R 90 minutes before coronary occlusion (RIPC+I/R). Arterial blood samples were taken after placebo or RIPC before I/R. In subgroups of pigs, bilateral cervical vagotomy, splenectomy, or splenic denervation were performed before PLA+I/R or RIPC+I/R, respectively. In pigs with RIPC+I/R, infarct size (percentage of area at risk) was less than in those with PLA+I/R (23±12% versus 45±8%); splenectomy or splenic denervation abrogated (splenectomy+RIPC+I/R: 38±15%; splenic denervation+RIPC+I/R: 43±5%), and vagotomy attenuated (vagotomy+RIPC+I/R: 36±11%) RIPC protection. RIPC increased phosphorylation of STAT3 (signal transducer and activator of transcription 3) in left ventricular biopsies taken at early reperfusion. Splenectomy or splenic denervation, but not vagotomy, abolished this increased phosphorylation. In rats with vagotomy, splenectomy, or splenic denervation, RIPC (3×5/5 minutes of hindlimb occlusion/reperfusion) or placebo was performed, respectively. Hearts were isolated, saline perfused, and subjected to 30/120-minute global I/R. With RIPC, infarct size (percentage of ventricular mass) was less (20±7%) than with placebo (37±6%), and vagotomy, splenectomy, or splenic denervation abrogated RIPC protection (38±12%, 36±9%, and 36±7%), respectively. Rat spleens were isolated, saline perfused, and splenic effluate (SEff) was sampled after infusion with carbachol (SEff_carbachol) or saline (SEff_saline). Pig plasma or SEff was infused into isolated perfused rat hearts subjected to global I/R. Infarct size was less with infusion of RIPC+I/R_plasma+ (24±6%) than with PLA+I/R_plasma (40±8%), vagotomy+PLA+I/R_plasma (39±11%), splenectomy+PLA+I/R_plasma (35±8%), vagotomy+RIPC+I/R_plasma (40±9%), splenectomy+RIPC+I/R_plasma (33±9%), or splenic denervation+RIPC+I/R_plasma (39±8%), respectively. With infusion of SEff_carbachol, infarct size was less than with infusion of SEff_saline (24 [19-27]% versus 35 [32-38]%).

CONCLUSIONS

Activation of a vago-splenic axis is causally involved in RIPC cardioprotection.

Mechanisms of Acupuncture Therapy for Simple Obesity: An Evidence-Based Review of Clinical and Animal Studies on Simple Obesity

Simple obesity is a worldwide epidemic associated with rapidly growing morbidity and mortality which imposes an enormous burden on individual and public health. As a part of Traditional Chinese Medicine (TCM), acupuncture has shown the positive efficacy in the management of simple obesity. In this article, we comprehensively review the clinical and animal studies that demonstrated the potential mechanisms of acupuncture treatment for simple obesity. Clinical studies suggested that acupuncture regulates endocrine system, promotes digestion, attenuates oxidative stress, and modulates relevant molecules of metabolism in patients of simple obesity. Evidence from laboratory indicated that acupuncture regulates lipid metabolism, modulates inflammatory responses, and promotes white adipose tissue browning. Acupuncture also suppresses appetite through regulating appetite regulatory hormones and the downstream signaling pathway. The evidence from clinical and animal studies indicates that acupuncture induces multifaceted regulation through complex mechanisms and moreover a single factor may not be enough to explain the beneficial effects against simple obesity.

The gut microbiome of Mexican children affected by obesity

Obesity is a metabolic disorder and global health issue. In Mexico 34.4% of children between 5 and 11 years-old are overweight or obese. Here we address this issue studying the gut microbiome in a sample of Mexican children affected by obesity. We performed metagenomic shotgun-sequencing of DNA isolated from fecal samples from a cohort of normal weight and obese Mexican children using Illumina platform with HiSeq 2500. We also examined their metabolic factors and fecal short-chain fatty acids concentration. The results show that a remarkable dysbiosis of bacteria, archaea and viruses was not observed in the obese children group compared to the normal weight group; however, the archaeal community exhibited an increase of unclassified Methanobrevibacter spp. in obese children. The bacterial communities of all participants were clustered into three different enterotypes. Most normal weight children have a gut bacterial community dominated by Ruminococcus spp. (Enterotype 3), while most obese children had a community dominated by Prevotella spp. (Enterotype 2). On the other hand, changes in the gut microbiome were correlated with clinical metadata and could be used to stratify individuals based on their phenotype. The species Megamonas spp. were over-represented in obese children, whereas members of the family Oscillospiraceae were depleted in the same individuals and negatively correlated with levels of serum cholesterol. A microbiome comparative metabolic pathway analysis showed that two KEGG pathway modules of glycolysis, Glycolysis I (from Glucose 6-Phosphate), and Glycolysis II (from Fructose 6-Phosphate) were significantly overrepresented in normal weight children. Our results establish specific alterations in the gut microbiome of Mexican children affected of obesity, along with clinical alterations, providing information on the microbiome composition that may be useful for prognosis, diagnosis, and treatment.

Lignins isolated from Prickly pear cladodes of the species Opuntia fícus-indica (Linnaeus) Miller and Opuntia cochenillifera (Linnaeus) Miller induces mice splenocytes activation, proliferation and cytokines production

Opuntia fícus-indica and Opuntia cochenillifera are species of Cactaceae, found in the arid regions of the planet. They present water, cellulose, hemicellulose, pectins, extractives, ashes and lignins. Here we aimed to study the immunomodulatory action of lignins from these two species against mice splenocytes, since no study for this purpose has yet been reported. The antioxidant activities of these lignins were evaluated by the DPPH, ABTS, NO assays and total antioxidant activity. Cytotoxicity was evaluated through Annexin V-FITC and propidium iodide-PE probs and cell proliferation was determined by CFSE. Immunomodulation studies with Opuntia lignins obtained were performed through investigation of ROS levels, cytosolic calcium release, changes on mitochondrial membrane potential, cytokine production and NO release. Results showed that Opuntia cochenillifera lignin presented more phenolic amount and antioxidant activities than Opuntia ficius-indica. Both lignins showed high cell viability (>96%) and cell proliferation. Activation signal was observed for both lignins with increase of ROS and cytosolic calcium levels, and changes in mitochondrial membrane potential. In addition, lignins induced high TNF-α, IL-6 and IL-10 production and reduced NO release. Therefore, these lignins present great potential to be used as molecules with a proinflammatory profile, being shown as a promising therapeutic agent.

Supplementation of grape seed and skin extract to orlistat therapy prevents high-fat diet-induced murine spleen lipotoxicity

Spleen is the largest lymphoid organ and obesity is related to an elevated risk of immunity dysfunction. The mechanism whereby fat adversely affects the spleen is poorly understood. This study was designed to assess the effectiveness of grape seed and skin extract (GSSE) and orlistat (Xenical, Xe) on high-fat diet (HFD)-induced spleen lipotoxicity. Obese rats were treated either with GSSE (4 g/kg body weight) or Xe (2 mg/kg body weight) or GSSE+Xe and monitored for weight loss for 3 months. Animals were then sacrificed and their spleen used for the evaluation of lipotoxicity-induced oxidative stress and inflammation as well as the putative protection afforded by GSSE and Xe treatment. HFD induced body weight gain and glycogen accumulation into the spleen; ectopic deposition of cholesterol and triglycerides and an oxidative stress characterized by increased lipoperoxidation and carbonylation; inhibition of antioxidant enzyme activities, such as catalase, glutathione peroxidase, and superoxide dismutase; depletion of zinc and copper; and a concomitant increase in calcium. HFD also increased plasma pro-inflammatory cytokines, such as interleukin (IL)-6, IL-17A, tumour necrosis factor alpha, and C-reactive protein, and decreased plasma IL-10 and adiponectin. Importantly, GSSE counteracted all the deleterious effects of HFD on spleen (i.e., lipotoxicity, oxidative stress, and inflammation) and the best protection was obtained when combining Xe+GSSE. Combining GSSE with Xe prevented against fat-induced spleen lipotoxicity, oxidative stress, and inflammation; this combination may be beneficial in other diseases related to the spleen.