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Despite the known link between obesity and insulin resistance (IR) to chronic low-grade inflammation, new markers capable of early IR detection are needed. Immune cells are components of adipose tissue's (AT) stromal vascular fraction (SVF) that regulate AT homeostasis. The altered phenotype and function of AT-infiltrating immune cells may contribute to the development and maintenance of local AT inflammation observed under obesity-induced IR conditions. Impaired AT-specific immunometabolic function may influence the whole organism. Therefore, AT-infiltrating immune cells may be important players in the development of obesity-related metabolic complications, such as type 2 diabetes mellitus (T2DM). B and T cells, particularly CD20+ T cells, play important roles in human pathology, such as autoimmune disease and cancer. However, the question remains as to whether CD20+ T cells have an important contribution to the development of obesity-related IR. While circulating CD20+ T cells are mostly of the central memory phenotype (i.e. antigen-experienced T cells with the ability to home to secondary lymphoid organs), tissues-infiltrated CD20+ T cells are predominantly of the effector memory phenotype (i.e. antigen-experienced T cells that preferentially infiltrate peripheral tissues). The latter produce pro-inflammatory cytokines, such as IFN-γ and IL-17, which play a role in obesity-related IR development. This review describes the CD20 molecule and its presence in both B and T cells, shedding light on its ontogeny and function, in health and disease, with emphasis on AT. The link between CD20+ T cell dysregulation, obesity, and IR development supports the role of CD20+ T cells as markers of adipose tissue dysmetabolism. [ABSTRACT FROM AUTHOR]

Introduction: Diabetes mellitus (DM) impairs wound healing. The aim was to determine whether DM influences mitochondrial respiration in wounded skin (WS) and non‐wounded skin (NWS), in a pre‐clinical wound healing model of streptozotocin (STZ)‐induced diabetes. Methods: Six weeks after diabetes induction, two wounds were created in the back of C57BL/J6 mice. Using high‐resolution respirometry (HRR), oxygen flux was measured, in WS and NWS, using two substrate‐uncoupler‐inhibitor titration protocols, at baseline (day 0), day 3 and 10 post‐wounding, in STZ‐DM and non‐diabetic (NDM) mice. Flux control ratios for the oxidative phosphorylation (OXPHOS) capacity were calculated. Results: A significant increase in mitochondrial respiration was observed in STZ‐DM skin compared to control skin at baseline. The OXPHOS capacity was decreased in WS under diabetes at day 3 post‐wounding (inflammation phase). However, at day 10 post‐wounding (remodeling phase), the OXPHOS capacity was higher in WS from STZ‐DM compared to NDM mice, and compared to NWS from STZ‐DM mice. A significant relative contribution of pyruvate, malate and glutamate (PMG) oxidation to the OXPHOS capacity was observed in WS compared to NWS from STZ‐DM mice, at day 10, while the relative contribution of fatty acid oxidation to the OXPHOS capacity was higher in NWS. The OXPHOS capacity is altered in WS from STZ‐DM compared to NDM mice across the healing process, and so is the substrate contribution in WS and NWS from STZ‐DM mice, at each time point. Conclusion: HRR may be a sensitive tool to evaluate the underlying mechanisms of tissue repair during wound healing. [ABSTRACT FROM AUTHOR]

Low-grade inflammation is closely linked to obesity and obesity-related comorbidities; therefore, immune cells have become an important topic in obesity research. Here, we performed a deep phenotypic characterization of circulating T cells in people with obesity, using flow cytometry. Forty-one individuals with obesity (OB) and clinical criteria for bariatric surgery were enrolled in this study. We identified and quantified 44 different circulating T cell subsets and assessed their activation status and the expression of immune-checkpoint molecules, immediately before (T1) and 7–18 months after (T2) the bariatric surgery. Twelve age- and sex-matched healthy individuals (nOB) were also recruited. The OB participants showed higher leukocyte counts and a higher percentage of neutrophils. The percentage of circulating Th1 cells were negatively correlated to HbA1c and insulin levels. OB Th1 cells displayed a higher activation status and lower PD-1 expression. The percentage of Th17 and Th1/17 cells were increased in OB, whereas the CD4+ Tregs' percentage was decreased. Interestingly, a higher proportion of OB CD4+ Tregs were polarized toward Th1- and Th1/17-like cells and expressed higher levels of CCR5. Bariatric surgery induced the recovery of CD4+ Treg cell levels and the expansion and activation of Tfh and B cells. Our results show alterations in the distribution and phenotype of circulating T cells from OB people, including activation markers and immune-checkpoint proteins, demonstrating that different metabolic profiles are associated to distinct immune profiles, and both are modulated by bariatric surgery. [ABSTRACT FROM AUTHOR]

Obesity and type 2 diabetes (T2D) are severe metabolic diseases due to inappropriate lifestyle and genetic factors and their prevention/treatment cause serious problems. Therefore, searching for effective and safe approaches to control obesity and T2D is an essential challenge. This study presents the knowledge regarding the possible use of traditional fermented condiments (TFC), a known major source of bioactive compounds (BACs), as an adjuvant treatment for obesity and T2D. Data on antiobesity, antidiabetic, and different mechanisms of BACs action of TFC were collected using a methodical search in PubMed, Scopus databases, Web of Science, SciELO, and the Cochrane Library. We discuss the mechanisms by which BCs prevent or treat obesity and T2D. The effects of TFC on obesity and T2D have been found both in animal, human, and clinical studies. The findings demonstrated that BACs in TFC confer potential promising antiobesity and antidiabetic effects. Because of the potential therapeutic significance of bioactive ingredients, the consumption of TFC could be recommended as a functional condiment. Nevertheless, further investigation is required in more clinical studies of TFC to support the formulation of functional fermented condiments and nutraceutical and pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Diabetic foot ulcers (DFU) are one of the most serious and devastating complications of diabetes and account for a significant decrease in quality of life and costly healthcare expenses worldwide. This condition affects around 15% of diabetic patients and is one of the leading causes of lower limb amputations. DFUs generally present poor clinical outcomes, mainly due to the impaired healing process and the elevated risk of microbial infections which leads to tissue damage. Nowadays, antimicrobial resistance poses a rising threat to global health, thus hampering DFU treatment and care. Faced with this reality, it is pivotal to find greener and less environmentally impactful alternatives for fighting these resistant microbes. Antimicrobial peptides are small molecules that play a crucial role in the innate immune system of the host and can be found in nature. Some of these molecules have shown broad-spectrum antimicrobial properties and wound-healing activity, making them good potential therapeutic compounds to treat DFUs. This review aims to describe antimicrobial peptides derived from green, eco-friendly processes that can be used as potential therapeutic compounds to treat DFUs, thereby granting a better quality of life to patients and their families while protecting our fundamental bio-resources. [ABSTRACT FROM AUTHOR]

Epigenetic mechanisms, such as DNA methylation, regulate gene expression and play a role in the development of insulin resistance. This study evaluates how the BMI z-score (BMIz) and the homeostatic model assessment of insulin resistance (HOMA-IR), alone or in combination, relate to clinical outcomes and DNA methylation patterns in prepubertal children. DNA methylation in peripheral blood mononuclear cells (PBMCs) and clinical outcomes were measured in a cohort of 41 prepubertal children. Children with higher HOMA-IR had higher blood pressure and plasma lactate levels while children with higher BMIz had higher triglycerides levels. Moreover, the DNA methylation analysis demonstrated that a 1 unit increase in the BMIz was associated with a 0.41 (95% CI: 0.29, 0.53) increase in methylation of a CpG near the PPP6R2 gene. This gene is important in the regulation of NF-kB expression. However, there was no strong evidence that the BMIz and the HOMA-IR were synergistically related to any clinical or DNA methylation outcomes. In summary, the results suggest that obesity and insulin resistance may impact metabolic health both independently in prepubertal children. In addition, obesity also has an impact on the DNA methylation of the PPP6R2 gene. This may be a novel underlying starting point for the systemic inflammation associated with obesity and insulin resistance, in this population. [ABSTRACT FROM AUTHOR]

Introduction: Thoracic perivascular adipose tissue (tPVAT) has a phenotype resembling brown AT. Dysfunctional tPVAT appears to be linked to vascular dysfunction. Methods: We evaluated uncoupling protein 1 (UCP1) expression by Western blot, oxidative stress by measuring lipid peroxidation, the antioxidant capacity by HPLC and spectrophotometry, and mitochondrial respiration by high-resolution respirometry (HRR) in tPVAT, compared to inguinal white AT (iWAT), obtained from non-diabetic (NDM) and streptozocin-induced diabetic (STZ-DM) mice. Mitochondrial respiration was assessed by HRR using protocol 1: complex I and II oxidative phosphorylation (OXPHOS) and protocol 2: fatty acid oxidation (FAO) OXPHOS. OXPHOS capacity in tPVAT was also evaluated after UCP1 inhibition by guanosine 5'-diphosphate (GDP). Results: UCP1 expression was higher in tPVAT when compared with iWAT in both NDM and STZ-DM mice. The malondialdehyde concentration was elevated in tPVAT from STZ-DM compared to NDM mice. Glutathione peroxidase and reductase activities, as well as reduced glutathione levels, were not different between tPVAT from NDM and STZ-DM mice but were lower compared to iWAT of STZ-DM mice. OXPHOS capacity of tPVAT was significantly decreased after UCP1 inhibition by GDP in protocol 1. While there were no differences in the OXPHOS capacity between NDM and STZ-DM mice i n protocol 1, it was increased in STZ-DM compared to NDM mice in protocol 2. Moreover, complex II- and FAO-linked respiration were elevated in STZ-DM mice under UCP1 inhibition. Conclusions: Pharmacological therapies could be targeted to modulate UCP1 activity with a significant impact in the uncoupling of mitochondrial bioenerg etics in tPVAT. [ABSTRACT FROM AUTHOR]

Epigenetic mechanisms, such as DNA methylation, regulate gene expression and play a role in the development of insulin resistance. This study evaluates how the BMI z-score (BMIz) and the homeostatic model assessment of insulin resistance (HOMA-IR), alone or in combination, relate to clinical outcomes and DNA methylation patterns in prepubertal children. DNA methylation in peripheral blood mononuclear cells (PBMCs) and clinical outcomes were measured in a cohort of 41 prepubertal children. Children with higher HOMA-IR had higher blood pressure and plasma lactate levels while children with higher BMIz had higher triglycerides levels. Moreover, the DNA methylation analysis demonstrated that a 1 unit increase in the BMIz was associated with a 0.41 (95% CI: 0.29, 0.53) increase in methylation of a CpG near the PPP6R2 gene. This gene is important in the regulation of NF-kB expression. However, there was no strong evidence that the BMIz and the HOMA-IR were synergistically related to any clinical or DNA methylation outcomes. In summary, the results suggest that obesity and insulin resistance may impact metabolic health both independently in prepubertal children. In addition, obesity also has an impact on the DNA methylation of the PPP6R2 gene. This may be a novel underlying starting point for the systemic inflammation associated with obesity and insulin resistance, in this population. [ABSTRACT FROM AUTHOR]

Adipose tissue expansion and subsequent metabolic dysfunction has been considered one of the major risk factors for development of cardiometabolic disease. Epicardial adipose tissue (EAT) in particular is a unique subtype of visceral adipose tissue located on the surface of the heart, around the coronary arteries. Due to its proximity, EAT can modulate the local metabolic and immune function of cardiomyocytes and coronary arteries. Several microRNAs have been described as key players in both cardiac and vascular function that when dysregulated will contribute to dysfunction. Here we review the influence of obesity in the crosstalk between specific adipose tissue types, in particular the EAT‐secreted microRNAs, as key modulators of cardiac disease progression, not only as early biomarkers but also as therapeutic targets for cardiometabolic disease. [ABSTRACT FROM AUTHOR]

Mechanical stresses associated with physical activity (PA) have beneficial effects on increasing BMD and improving bone quality. However, a high‐fat diet (HFD) and obesity tend to have negative effects on bone, by increasing bone marrow adiposity leading to increased excretion of proinflammatory cytokines, which activate RANKL‐induced bone resorption. In the current study, whether short‐term increased PA via access to voluntary wheel running during early life has persistent and protective effects on HFD‐induced bone resorption was investigated. Sixty 4‐week‐old male C57BL6/J mice were divided into two groups postweaning: without or with PA (access to voluntary running wheel 7–8 km/day) for 4 weeks. After 4 weeks with or without PA, mice were further subdivided into control diet or HFD groups for 8 weeks, and then all animals were switched back to control diet for an additional 4 weeks. Mice from the HFD groups were significantly heavier and obese; however, after 4 weeks of additional control diet their body weights returned to levels of mice on continuous control diet. Using μ‐CT and confirmed by pQCT of tibias and spines ex vivo, it was determined that bone volume and trabecular BMD were significantly increased with PA in control diet animals compared with sedentary animals without access to wheels, and such anabolic effects of PA on bone were sustained after ceasing PA in adult mice. Eight weeks of a HFD deteriorated bone development in mice. Unexpectedly, early‐life PA did not prevent persistent effects of HFD on deteriorating bone quality; in fact, it exacerbated a HFD‐induced inflammation, osteoclastogenesis, and trabecular bone loss in adult mice. In accordance with these data, signal transduction studies revealed that a HFD‐induced Ezh2, DNA methyltransferase 3a, and nuclear factor of activated T‐cells 1 expression were amplified in nonadherent hematopoietic cells. In conclusion, short‐term increased PA in early life is capable of increasing bone mass; however, it alters the HFD‐induced bone marrow hematopoietic cell‐differentiation program to exacerbate increased bone resorption if PA is halted. © 2021 Arkansas Children's Nutrition Center. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Age‐associated mitochondrial dysfunction and oxidative damage are primary causes for multiple health problems including sarcopenia and cardiovascular disease (CVD). Though the role of Nrf2, a transcription factor that regulates cytoprotective gene expression, in myopathy remains poorly defined, it has shown beneficial properties in both sarcopenia and CVD. Sulforaphane (SFN), a natural compound Nrf2‐related activator of cytoprotective genes, provides protection in several disease states including CVD and is in various stages of clinical trials, from cancer prevention to reducing insulin resistance. This study aimed to determine whether SFN may prevent age‐related loss of function in the heart and skeletal muscle. Cohorts of 2‐month‐old and 21‐ to 22‐month‐old mice were administered regular rodent diet or diet supplemented with SFN for 12 weeks. At the completion of the study, skeletal muscle and heart function, mitochondrial function, and Nrf2 activity were measured. Our studies revealed a significant drop in Nrf2 activity and mitochondrial functions, together with a loss of skeletal muscle and cardiac function in the old control mice compared to the younger age group. In the old mice, SFN restored Nrf2 activity, mitochondrial function, cardiac function, exercise capacity, glucose tolerance, and activation/differentiation of skeletal muscle satellite cells. Our results suggest that the age‐associated decline in Nrf2 signaling activity and the associated mitochondrial dysfunction might be implicated in the development of age‐related disease processes. Therefore, the restoration of Nrf2 activity and endogenous cytoprotective mechanisms by SFN may be a safe and effective strategy to protect against muscle and heart dysfunction due to aging. [ABSTRACT FROM AUTHOR]

Background: Neonatal diet impacts many physiological systems and can modify risk for developing metabolic disease and obesity later in life. Less well studied is the effect of postnatal diet (e.g., comparing human milk (HM) or milk formula (MF) feeding) on mitochondrial bioenergetics. Such effects may be most profound in splanchnic tissues that would have early exposure to diet-associated or gut microbe-derived factors. Methods: To address this question, we measured ileal and liver mitochondrial bioenergetics phenotypes in male piglets fed with HM or MF from day 2 to day 21 age. Ileal and liver tissue were processed for mitochondrial respiration (substrate only [pyruvate, malate, glutamate], substrate + ADP, and proton "leak" post-oligomycin; measured by Oroboros methods), mitochondrial DNA (mtDNA) and metabolically-relevant gene expression analyses. Results: No differences between the diet groups were observed in mitochondrial bioenergetics indices in ileal tissue. In contrast, ADP-dependent liver Complex I-linked OXPHOS capacity and Complex I + II-linked OXPHOS capacity were significantly higher in MF animals relative to HM fed piglets. Interestingly, p53, Trap1, and Pparβ transcript abundances were higher in MF-fed relative to HM-fed piglets in the liver. Mitochondrial DNA copy numbers (normalized to nuclear DNA) were similar within-tissue regardless of postnatal diet, and were ~ 2–3 times higher in liver vs. ileal tissue. Conclusion: While mechanisms remain to be identified, the data indicate that neonatal diet can significantly impact liver mitochondrial bioenergetics phenotypes, even in the absence of a change in mtDNA abundance. Since permeabilized liver mitochondrial respiration was increased in MF piglets only in the presence of ADP, it suggests that formula feeding led to a higher ATP turnover. Specific mechanisms and signals involved with neonatal diet-associated differences in liver bioenergetics remain to be elucidated. [ABSTRACT FROM AUTHOR]

Skeletal muscle mitochondrial respiration is thought to be altered in obesity, insulin resistance, and type 2 diabetes; however, the invasive nature of tissue biopsies is an important limiting factor for studying mitochondrial function. Recent findings suggest that bioenergetics profiling of circulating cells may inform on mitochondrial function in other tissues in lieu of biopsies. Thus, we sought to determine whether mitochondrial respiration in circulating cells [peripheral blood mononuclear cells (PBMCs) and platelets] reflects that of skeletal muscle fibers derived from the same subjects. PBMCs, platelets, and skeletal muscle (vastus lateralis) samples were obtained from 32 young (25-35 yr) women of varying body mass indexes. With the use of extracellular flux analysis and high-resolution respirometry, mitochondrial respiration was measured in intact blood cells as well as in permeabilized cells and permeabilized muscle fibers. Respiratory parameters were not correlated between permeabilized muscle fibers and intact PBMCs or platelets. In a subset of samples (n = 12-13) with permeabilized blood cells available, raw measures of substrate (pyruvate, malate, glutamate, and succinate)-driven respiration did not correlate between permeabilized muscle (per mg tissue) and permeabilized PBMCs (per 106 cells); however, complex I leak and oxidative phosphorylation coupling efficiency correlated between permeabilized platelets and muscle (Spearman's p= 0.64, P = 0.030; Spearman's p = 0.72, P = 0.010, respectively). Our data indicate that bioenergetics phenotypes in circulating cells cannot recapitulate muscle mitochondrial function. Select circulating cell bioenergetics phenotypes may possibly inform on overall metabolic health, but this postulate awaits validation in cohorts spanning a larger range of insulin resistance and type 2 diabetes status. [ABSTRACT FROM AUTHOR]

Background/Aims: Vascular complications contribute significantly to the extensive morbidity and mortality rates observed in people with diabetes. Despite well known that the diabetic kidney and heart exhibit imbalanced angiogenesis, the mechanisms implicated in this angiogenic paradox remain unknown. In this study, we examined the angiogenic and metabolic gene expression profile (GEP) of endothelial cells (ECs) isolated from a mouse model with type1 diabetes mellitus (T1DM). Methods: ECs were isolated from kidneys and hearts of healthy and streptozocin (STZ)-treated mice. RNA was then extracted for molecular studies. GEP of 84 angiogenic and 84 AMP-activated Protein Kinase (AMPK)-dependent genes were examined by microarrays. Real time PCR confirmed the changes observed in significantly altered genes. Microvessel density (MVD) was analysed by immunohistochemistry, fibrosis was assessed by the Sirius red histological staining and connective tissue growth factor (CTGF) was quantified by ELISA. Results: The relative percentage of ECs and MVD were increased in the kidneys of T1DM animals whereas the opposite trend was observed in the hearts of diabetic mice. Accordingly, the majority of AMPK-associated genes were upregulated in kidneys and downregulated in hearts of these animals. Angiogenic GEP revealed significant differences in Tgfβ, Notch signaling and Timp2 in both diabetic organs. These findings were in agreement with the angiogenesis histological assays. Fibrosis was augmented in both organs in diabetic as compared to healthy animals. Conclusion: Altogether, our findings indicate, for the first time, that T1DM heart and kidney ECs present opposite metabolic cues, which are accompanied by distinct angiogenic patterns. These findings enable the development of innovative organ-specific therapeutic strategies targeting diabetic-associated vascular disorders. [ABSTRACT FROM AUTHOR]

Background/Aims: Vascular complications contribute significantly to the extensive morbidity and mortality rates observed in people with diabetes. Despite well known that the diabetic kidney and heart exhibit imbalanced angiogenesis, the mechanisms implicated in this angiogenic paradox remain unknown. In this study, we examined the angiogenic and metabolic gene expression profile (GEP) of endothelial cells (ECs) isolated from a mouse model with type1 diabetes mellitus (T1DM). Methods: ECs were isolated from kidneys and hearts of healthy and streptozocin (STZ)-treated mice. RNA was then extracted for molecular studies. GEP of 84 angiogenic and 84 AMP-activated Protein Kinase (AMPK)-dependent genes were examined by microarrays. Real time PCR confirmed the changes observed in significantly altered genes. Microvessel density (MVD) was analysed by immunohistochemistry, fibrosis was assessed by the Sirius red histological staining and connective tissue growth factor (CTGF) was quantified by ELISA. Results: The relative percentage of ECs and MVD were increased in the kidneys of T1DM animals whereas the opposite trend was observed in the hearts of diabetic mice. Accordingly, the majority of AMPK-associated genes were upregulated in kidneys and downregulated in hearts of these animals. Angiogenic GEP revealed significant differences in Tgfβ, Notch signaling and Timp2 in both diabetic organs. These findings were in agreement with the angiogenesis histological assays. Fibrosis was augmented in both organs in diabetic as compared to healthy animals. Conclusion: Altogether, our findings indicate, for the first time, that T1DM heart and kidney ECs present opposite metabolic cues, which are accompanied by distinct angiogenic patterns. These findings enable the development of innovative organ-specific therapeutic strategies targeting diabetic-associated vascular disorders. [ABSTRACT FROM AUTHOR]

Neurotensin, substance P, and insulin have been demonstrated to improve wound healing in vivo. However, the mechanism behind their effect is still not fully understood. This study investigates the effects leading to enhanced scratch closure by these peptides in vitro. The skin keratinocyte cell line, HaCaT, was used to test scratch closure effects of the peptides and alterations of cytokine levels. HUVEC cells were used to test the angiogenic effect of the peptides. Furthermore, clinical isolates of Staphylococcus lugdunensis were used to examine the potential antimicrobial activity of each peptide. Our results demonstrate that neurotensin, substance P, and insulin had significant migratory effects in scratch assays were neurotensin had the lowest effect. Furthermore, we investigated use of the peptides in combination. When substance P was used in combination with neurotensin, the cell migratory capacity was decreased, and the peptides showed a negative correlation (r = −0.298, P < .001). Neurotensin and insulin significantly increased levels of monocyte chemoattractant protein‐1 (P < .001) secreted from white blood cells, whereas substance P showed a tendency. Interestingly, neurotensin increased the level of monocyte chemoattractant protein‐1 significantly compared to substance P (P < .01). Additionally, the peptides decreased TNFα mRNA levels (P < .001) in HaCaT cells, whereas only neurotensin and insulin decreased IL‐8 mRNA (P < .001) but had no significant effect on IL‐6 mRNA levels. Surprisingly, substance P increased IL‐6 mRNA 9‐fold (P < .001). Furthermore, we demonstrate that the peptides increased angiogenesis in the HUVEC cells (P < .001). Finally, S. lugdunensis isolates were not susceptible to the peptides. We demonstrate that the peptides worked differently on HaCaT cells, but substance P acted differently than neurotensin on cytokine levels expression as well as on migration of HaCaT cells. On the contrary, neurotensin and insulin worked similarly. All of these aspects are crucial for proper wound healing, and the results suggest multiple mechanisms for wound‐healing properties of these peptides. [ABSTRACT FROM AUTHOR]

Overweight and obesity are major problems in today's society, driving the prevalence of diabetes and its related complications. It is important to understand the molecular mechanisms underlying the chronic complications in diabetes in order to develop better therapeutic approaches for these conditions. Some of the most important complications include macrovascular abnormalities, e.g., heart disease and atherosclerosis, and microvascular abnormalities, e.g., retinopathy, nephropathy and neuropathy, in particular diabetic foot ulceration. The highly conserved endogenous small non-coding RNA molecules, the micro RNAs (miRNAs) have in recent years been found to be involved in a number of biological processes, including the pathogenesis of disease. Their main function is to regulate post-transcriptional gene expression by binding to their target messenger RNAs (mRNAs), leading to mRNA degradation, suppression of translation or even gene activation. These molecules are promising therapeutic targets and demonstrate great potential as diagnostic biomarkers for disease. This review aims to describe the most recent findings regarding the important roles of miRNAs in diabetes and its complications, with special attention given to the different phases of diabetic wound healing. [ABSTRACT FROM AUTHOR]

Systemic inflammation is associated with impaired wound healing in diabetes mellitus (DM) patients. Using immunohistochemistry techniques, the authors investigated changes in skin inflammation and skin blood vessels in human and experimental diabetes. Comparing to the non-DM human subjects, the total number of inflammatory cells per biopsy and the number of inflammatory cells around blood vessels, a strong indication of inflammation, were higher in DM subjects irrespective of their risk for developing diabetic foot ulcer. Inflammatory cell infiltration was robustly increased in all DM animal models compared with their non-DM controls. The number and density of blood vessels and CD31 positive proliferating endothelial cells around preexisting skin vessels was also higher in the DM patients. However, there were no differences in the skin blood flow between the non-DM and DM subjects. The number of skin blood vessels was also increased in the DM animals; however, these differences were less obvious than the ones observed for inflammatory cells. We conclude that skin inflammation and skin blood vessel density is increased in diabetic human subjects and in rodent and rabbit models of diabetes. [ABSTRACT FROM AUTHOR]

Epicardial and perivascular fat depot size is considered an index of cardiac and visceral obesity. The functional and anatomic proximity of epicardial adipose tissue (EAT) to myocardium has drawn increasing attention in recent years among researchers attempting to elucidate its putative role as an endocrine organ. This includes the role of EAT as a lipid storing depot and as an inflammatory tissue secreting cytokines and chemokines under pathogenic conditions such as cardiovascular diseases. In this review, we discuss the current state of knowledge regarding the potential EAT mediators of inflammation and the paracrine cross-talk between EAT and the underlying myocardium. We also highlight the most recent findings on the causes and correlates of myocardial steatosis/cardiac lipotoxicity and its association with cardiac dysfunction [ABSTRACT FROM AUTHOR]

Research in pharmacological therapy has led to the availability of many antidiabetic agents. New recommendations for precision medicine and particularly precision nutrition may greatly contribute to the control and especially to the prevention of diabetes. This scenario greatly encourages the search for novel non-pharmaceutical molecules. In line with this, the daily and long-term consumption of diets rich in phenolic compounds, together with a healthy lifestyle, may have a protective role against the development of type 2 diabetes. In the framework of the described studies, there is clear evidence that the bio accessibility, bioavailability, and the gut microbiota are indeed affected by: the way phenolic compounds are consumed (acutely or chronically; as pure compounds, extracts, or in-side a whole meal) and the amount and the type of phenolic compounds (ex-tractable or non-extractable/macromolecular antioxidants, including non-bioavailable polyphenols and plant matrix complexed structures). In this review, we report possible effects of important, commonly consumed, phenolic-based nutraceuticals in pre-clinical and clinical diabetes studies. We highlight their mechanisms of action and their potential effects in health promotion. Translation of this nutraceutical-based approach still requires more and larger clinical trials for better elucidation of the mechanism of action toward clinical applications. [ABSTRACT FROM AUTHOR]

Provides information on a study that examined the clinical phenotype of individuals characterized by normal or low insulin receptor substrate-1 protein expression in fat cells as well as the potential molecular mechanisms related to the adipose tissue. Methodology of the study; Results and discussion on the study.

Perturbed angular correlation of γ-rays (PAC) spectroscopy has been used to investigate the angioten-sin-I-converting enzyme (ACE) of rabbit lung. By substituting the zinc ions in ACE with excited 111mCd2+ ions, analysis of PAC spectra gave directly the percentage of cadmium ions bound to ACE. The result of the analysis was a dissociation constant of about 1 μM for the cadmium-ACE complex,and a stoichiometry of two moles cadmium/mole enzyme. Cadmium binding is thus about two orders of magnitude weaker than zinc binding to ACE but two orders of magnitude stronger than cobalt binding. PAC spectra monitor the nuclear quadrupole interaction (NQI) for 111mCd. The NQI for ACE exhibits very low frequencies in the PAC spectra with a rather large spectral broadening. In the presence of inhibitor ramiprilat, the frequencies increase but the spectral broadening is about the same as for ACE without inhibitor. When the inhibitor captrophil is added, very high frequencies are obtained consistent with sulfur binding, but now with a narrow distribution of NQI;s. A simple molecular orbital analysis of the obtained NQI's has been performed, using a coordination sphere of two His, one Glu residue and a solvent ligand, equivalent to the zinc ligands in thermolysin and carboxypeptidase. the calculated spectral parameters could be modelled with the measured parameters if the solvent ligand is H2O in free ACE, carboxylate from ramiprilat in the ACE-ramiprilat complex and a mercapto group in the ACE-captropril complex. The coordination geometry for cadmium carboxypeptidase obtained by X-ray diffraction gives a calculated set of NQI parameters consistent with the measured parameters for cadmium in the captopril-ACE complex using a mercapto group as the solvent ligand. However, for ACE and its complex with ramiprilat, a significant distortion of the cadmium geometry for carboxypeptidase A had to be adopted ion order to calculate NQI's close to the experimental values. [ABSTRACT FROM AUTHOR]

Dietary factors modulate interactions between the microbiome, metabolome, and immune system. Sulforaphane (SFN) exerts effects on aging, cancer prevention and reducing insulin resistance. This study investigated effects of SFN on the gut microbiome and metabolome in old mouse model compared with young mice. Young (6–8 weeks) and old (21–22 months) male C57BL/6J mice were provided regular rodent chow ± SFN for 2 months. We collected fecal samples before and after SFN administration and profiled the microbiome and metabolome. Multi-omics datasets were analyzed individually and integrated to investigate the relationship between SFN diet, the gut microbiome, and metabolome. The SFN diet restored the gut microbiome in old mice to mimic that in young mice, enriching bacteria known to be associated with an improved intestinal barrier function and the production of anti-inflammatory compounds. The tricarboxylic acid cycle decreased and amino acid metabolism-related pathways increased. Integration of multi-omic datasets revealed SFN diet-induced metabolite biomarkers in old mice associated principally with the genera, Oscillospira, Ruminococcus, and Allobaculum. Collectively, our results support a hypothesis that SFN diet exerts anti-aging effects in part by influencing the gut microbiome and metabolome. Modulating the gut microbiome by SFN may have the potential to promote healthier aging. [ABSTRACT FROM AUTHOR]

Wound healing is a complex biological process that is impaired under diabetes conditions. Chronic non-healing wounds in diabetes are some of the most expensive healthcare expenditures worldwide. Early diagnosis and efficacious treatment strategies are needed. microRNAs (miRNAs), a class of 18–25 nucleotide long RNAs, are important regulatory molecules involved in gene expression regulation and in the repression of translation, controlling protein expression in health and disease. Recently, miRNAs have emerged as critical players in impaired wound healing and could be targets for potential therapies for non-healing wounds. Here, we review and discuss the mechanistic background of miRNA actions in chronic wounds that can shed the light on their utilization as specific wound healing biomarkers. [ABSTRACT FROM AUTHOR]

Peripheral neuropathy plays a role in chronic diabetic foot ulcers (DFUs), also leading to an imbalance in inflammation, as pro-inflammatory macrophages (M1) have difficulty switching to an anti-inflammatory phenotype (M2) contributing to a chronic inflammatory phase and healing impairment. Protein tyrosine phosphatase 1B (PTP1B), in the skin, is over expressed in diabetes and DFUs. We aimed to evaluate the role of PTP1B inhibition in macrophage under high glucose conditions. THP-1 monocytic cells were differentiated into macrophages, treated with the PTP1B inhibitor MSI-1436 (1 µM) and stimulated with LPS for 24h, under high glucose (25 mM) or normoglycemic conditions (5.5 mM). Cell viability was measured by MTT assay. The numbers of M1 and M2 macrophages were evaluated by immunocytochemistry by double staining with CD68 and TNF-α for M1 macrophages, and CD68 and CD163 for M2 macrophages. In addition, pro-inflammatory cytokine expression was analyzed by qRT-PCR. Oxidative stress was assessed by the DCFH-DA assay, heme oxygenase-1 (HO-1) enzyme levels were also measured by immunocytochemistry and Western blot. The treatment with MSI-1436 did not alter THP-1 cell viability. In inflammatory conditions (LPS), THP-1 cells grown under HG and treated with MSI-1436 showed an increase in M2 macrophages and a reduction in M1 macrophages (246 ± 26% and 102 ± 9%, p<0.05, of LPS treated cells, respectively). In addition, PTP1B inhibition induced a decrease in pro-inflammatory cytokine expression, IL-6, IL-1β and MCP-1, a decrease in ROS levels (78 ± 10% of LPS treated cells) and an increase in HO-1 expression (290 ± 23%, p<0.05, of LPS treated cells). Inhibition of PTP1B in macrophages, under high glucose conditions, promotes a significant reduction in the inflammatory environment and oxidative stress via increase of HO-1 expression, suggesting that PTP1B is a potential therapeutic target for the treatment of chronic DFUs. Disclosure: A. Figueiredo: None. E.C. Leal: None. D. Santos: None. G. Gasiunaite: None. M. Delibegovic: None. E. Carvalho: None. Funding: Diabetes UK; Portuguese Foundation for Science and Technology; European Foundation for the Study of Diabetes; Portuguese Society of Diabetology [ABSTRACT FROM AUTHOR]

Diabetic neuropathy plays an important role in the development of chronic wounds. Endothelial progenitor cells (EPCs) are known important regulators of wound angiogenesis. However, the role of neuropeptides in EPC function, and particularly Neurotensin (NT), is unknown in diabetic wound healing. EPCs isolated from normal mice were cultured in high glucose (25 mM) or normoglicemia (5.5 mM) and treated with NT (25-400 nM) for 3 days. Moreover, EPCs isolated from streptozotocin (STZ)-induced diabetic mice were treated with NT (100 nM) for 3 days. Subsequently, EPC viability, cell adhesion and reactive oxygen species (ROS) levels were evaluated. To the in vivo wound healing model, 6 mm wounds were created in the dorsum of diabetic mice and wound progression was followed up to day 10. The wound edges were injected with ex-vivo diabetic bone marrow derived EPCs treated in culture with NT (100 nM) for 3 days, or EPCs without NT treatment, or vehicle. Angiogenesis was evaluated by immunohistochemistry. The viability of EPCs cultured under high glucose or EPCs from diabetic mice was improved by NT treatment. Also, EPCs from diabetic mice showed decreased adhesion (58% of control, p<0.05) and increased ROS levels (148% of control, p<0.05) when compared to control EPCs, and these effects were reversed by NT treatment. In addition, NT-treated EPCs, from diabetic mice, improved wound closure (day 10, 4% of original wound size) when compared with non-treated EPCs or vehicle (day 10, 32% and 35% of original wound size, respectively, p<0.05). Furthermore, NT-treated EPCs, from diabetic mice, increased neovascularization at the wound site (153% of vehicle, p<0.05) when compared with non-treated EPCs (115% of vehicle) or vehicle. These results show that neurotensin is able to improve the function of EPCs from diabetic animals, which are able to improve wound healing by promoting angiogenesis. The restoration of EPC function by neurotensin could improve their therapeutic effect for the treatment of chronic diabetic wounds. Disclosure: E.C. Leal: None. A. Figueiredo: None. E. Carvalho: None. Funding: Portuguese Foundation for Science and Technology; European Foundation for the Study of Diabetes; Portuguese Society of Diabetology [ABSTRACT FROM AUTHOR]

With increasing rates of childhood obesity, diagnoses of insulin resistance and type 2 diabetes (DM) in children is on the rise. Mitochondrial dysfunction is associated with insulin resistance and DM, therefore bioenergetics profiling of circulating cells may serve as a marker for mitochondrial dysfunction in insulin resistant subjects. The advantage of this biomarker is that others currently in use may not exhibit alterations until symptoms are already present. Mitochondrial bioenergetics (Seahorse XF96) was measured in peripheral blood mononuclear cells (PBMCs) and platelets. Levels of oxidative stress, post-translational modifications of protein tyrosine residues, 3-Nitrotyrosine and 3-Chlorotyrosine, reduced (GSH) and oxidized (GSSG) glutathione, as well as whole-body D31-palmitate oxidation were also assessed in healthy lean (HL; n=18), and overweight/obese (OW/OB; n=29) (BMI ≥85th percentile) 5-9 years old children. While maximal respiration was not different, the reserve capacity (RC) was increased in OW/OB compared to HL subjects in PBMC (45,6±4,7 vs. 32,1±7.7; p=0.05) and platelet (65,3±3.7 vs. 31,2±6,7; p=0.001). Importantly, 20% of these children already presented HbA1c levels above 6.5%. Moreover, 3-Chlorotyrosine was elevated (52,0±3,1 vs. 40,7±1,8; p=0.05), while GSH/GSSG and cysteine/cysteine (intracellular, extracellular redox buffers, respectively) tended to be decreased. Palmitate oxidation is being quantified. RC is a critical component of the cell's bioenergetics and can be used during increases in energy demand. Our results suggest significant metabolic adjustments to an excess in substrate availability and already compromised antioxidant defenses in 5-9 year old OW/OB children. Oxidative stress and damage occur when antioxidant defense mechanisms fail to counter-balance and control reactive oxygen species generated from endogenous oxidative metabolism or from pro-oxidant environmental exposures. Disclosure: E. Carvalho: None. S. Rose: None. M. Cotter: None. S.C. Bennuri: None. L.M. Delhey: None. G.A. Goode: None. A. Beebe: None. E. Børsheim: None. Funding: National Institute of General Medical Sciences (P20GM109096) [ABSTRACT FROM AUTHOR]

The article discusses the impact of autonomic nervous system function on the glucose and lipid metabolism levels in epicardial adipose tissue examined in heart failure patients. Topics discussed include research on orosomucoid secretion in adipose tissue and the relationship between cardiac autonomic function and epicardial adipose tissue. It also mentions the glucose and lipid metabolism levels in type 1 diabetes mellitus patients.

Background:To evaluate changes in endothelial progenitor cells (EPCs) and cytokines in patients with diabetic foot ulceration (DFU) in association with wound healing. Methods:We studied healthy subjects, diabetic patients not at risk of DFU, at risk of DFU and with active DFU. We prospectively followed the DFU patients over a 12-week period. We also investigated similar changes in diabetic rabbit and mouse models of wound healing. Results:All EPC phenotypes except the kinase insert domain receptor (KDR)+CD133+ were reduced in the at risk and the DFU groups compared to the controls. There were no major EPC differences between the control and not at risk group, and between the at risk and DFU groups. Serum stromal-cell derived factor-1 (SDF-1) and stem cell factor (SCF) were increased in DFU patients. DFU patients who healed their ulcers had lower CD34+KDR+ count at visits 3 and 4, serum c-reactive protein (CRP) and granulocyte-macrophage colony-stimulating factor (GM-CSF) at visit 1, interleukin-1 (IL-1) at visits 1 and 4. EPCs tended to be higher in both diabetic animal models when compared to their non-diabetic counterparts both before and ten days after wounding. Conclusions:Uncomplicated diabetes does not affect EPCs. EPCs are reduced in patients at risk or with DFU while complete wound healing is associated with CD34+KDR+ reduction, suggesting possible increased homing. Low baseline CRP, IL-1α and GM-CSF serum levels were associated with complete wound healing and may potentially serve as prognostic markers of DFU healing. No animal model alone is representative of the human condition, indicating the need for multiple experimental models. [ABSTRACT FROM AUTHOR]