Mechanisms of obesity and related pathologies: the macro- and microcirculation of adipose tissue

Ablation of FAM210A in Brown Adipocytes of Mice Exacerbates High-Fat Diet-Induced Metabolic Dysfunction

Thermogenesis of brown adipose tissue (BAT) provides metabolic benefits against pathologic conditions, such as type 2 diabetes, obesity, cardiovascular disease, and cancer. The thermogenic function of BAT relies on mitochondria, but whether mitochondrial remodeling is required for the beneficial effects of BAT remains unclear. We recently identified FAM210A as a BAT-enriched mitochondrial protein essential for cold-induced thermogenesis through the modulation of OPA1-dependent cristae remodeling. Here, we report a key role of FAM210A in the systemic response to a high-fat diet (HFD). We discovered that an HFD suppressed FAM210A expression, associated with excessive OPA1 cleavage in BAT. Ucp1-Cre-driven BAT-specific Fam210a knockout (Fam210aUKO) similarly elevated OPA1 cleavage, accompanied by whitening of BAT. When subjected to an HFD, Fam210aUKO mice gained similar fat mass as sibling control mice but developed glucose intolerance, insulin resistance, and liver steatosis. The metabolic dysfunction was associated with overall increased lipid content in both the liver and BAT. Additionally, Fam210aUKO leads to inflammation in white adipose tissue. These data demonstrate that FAM210A in BAT is necessary for counteracting HFD-induced metabolic dysfunction but not obesity.

ARTICLE HIGHLIGHTS

FAM210A regulates cold-induced mitochondrial remodeling through control of OPA1 cleavage, but whether it also plays a role in high-fat diet (HFD)-induced cristae remodeling is unknown. We asked if an HFD would alter the FAM210A level and OPA1 cleavage in brown adipose tissue (BAT) and how FAM210A loss of function would affect diet-induced obesity in mice. We found that an HFD diminished FAM210A expression and accelerated OPA1 cleavage in BAT, and Fam210a knockout exacerbated HFD-induced whitening of BAT, cold intolerance, liver steatosis, white adipose tissue inflammation, and metabolic dysfunction. Our work reveals a physiologic role of FAM210A-mediated BAT mitochondrial remodeling in systemic adaptation to an HFD and suggests that BAT mitochondria may be targeted to treat diet-induced metabolic dysfunction.

Role of low-density cholesterol and Interleukin-17 interaction in breast cancer pathogenesis and treatment

Breast cancer (BC) has become the most prevalent cancer worldwide, and further research is being conducted to deepen our understanding of its pathogenesis and treatment. Lipid metabolism disorder is a significant alteration in cancer cells, and the investigation into the role of Interleukin-17 (IL-17) in malignant tumors has emerged as a research focus in recent years. Thus, exploring changes in lipid metabolism and inflammatory factors in BC cells is crucial in identifying potential therapeutic targets. This article summarizes the progress made in the research on the main low-density cholesterol (LDL) transporter and IL-17 in lipid metabolism, and their potential involvement in the development of BC. The article aims to establish a theoretical foundation for the development of BC-related therapies.

α2δ1-mediated maladaptive sensory plasticity disrupts adipose tissue homeostasis following spinal cord injury

Spinal cord injury (SCI) increases the risk of cardiometabolic disorders, including hypertension, dyslipidemia, and insulin resistance. Not only does SCI lead to pathological expansion of adipose tissue, but it also leads to ectopic lipid accumulation in organs integral to glucose and insulin metabolism. The pathophysiological changes that underlie adipose tissue dysfunction after SCI are unknown. Here, we find that SCI exacerbates lipolysis in epididymal white adipose tissue (eWAT). Whereas expression of the α2δ1 subunit of voltage-gated calcium channels increases in calcitonin gene-related peptide-positive dorsal root ganglia neurons that project to eWAT, conditional deletion of the gene encoding α2δ1 in these neurons normalizes eWAT lipolysis after SCI. Furthermore, α2δ1 pharmacological blockade through systemic administration of gabapentin also normalizes eWAT lipolysis after SCI, preventing ectopic lipid accumulation in the liver. Thus, our study provides insight into molecular causes of maladaptive sensory processing in eWAT, facilitating the development of strategies to reduce metabolic and cardiovascular complications after SCI.

The Metabolic Syndrome, a Human Disease

This review focuses on the question of metabolic syndrome (MS) being a complex, but essentially monophyletic, galaxy of associated diseases/disorders, or just a syndrome of related but rather independent pathologies. The human nature of MS (its exceptionality in Nature and its close interdependence with human action and evolution) is presented and discussed. The text also describes the close interdependence of its components, with special emphasis on the description of their interrelations (including their syndromic development and recruitment), as well as their consequences upon energy handling and partition. The main theories on MS's origin and development are presented in relation to hepatic steatosis, type 2 diabetes, and obesity, but encompass most of the MS components described so far. The differential effects of sex and its biological consequences are considered under the light of human social needs and evolution, which are also directly related to MS epidemiology, severity, and relations with senescence. The triggering and maintenance factors of MS are discussed, with especial emphasis on inflammation, a complex process affecting different levels of organization and which is a critical element for MS development. Inflammation is also related to the operation of connective tissue (including the adipose organ) and the widely studied and acknowledged influence of diet. The role of diet composition, including the transcendence of the anaplerotic maintenance of the Krebs cycle from dietary amino acid supply (and its timing), is developed in the context of testosterone and β-estradiol control of the insulin-glycaemia hepatic core system of carbohydrate-triacylglycerol energy handling. The high probability of MS acting as a unique complex biological control system (essentially monophyletic) is presented, together with additional perspectives/considerations on the treatment of this 'very' human disease.

Advances in lymphedema: An under-recognized disease with a hopeful future for patients

Lymphedema has traditionally been underappreciated by the healthcare community. Understanding of the underlying pathophysiology and treatments beyond compression have been limited until recently. Increased investigation has demonstrated the key role of inflammation and resultant fibrosis and adipose deposition leading to the clinical sequelae and associated reduction in quality of life with lymphedema. New imaging techniques including magnetic resonance imaging (MRI), indocyanine green lymphography, and high-frequency ultrasound offer improved resolution and understanding of lymphatic anatomy and flow. Nonsurgical therapy with compression, exercise, and weight loss remains the mainstay of therapy, but growing surgical options show promise. Physiologic procedures (lymphovenous anastomosis and vascularized lymph node transfers) improve lymphatic flow in the diseased limb and may reduce edema and the burden of compression. Debulking, primarily with liposuction to remove the adipose deposition that has accumulated, results in a dramatic decrease in limb girth in appropriately selected patients. Though early, there are also exciting developments of potential therapeutic targets tackling the underlying drivers of the disease. Multidisciplinary teams have developed to offer the full breadth of evaluation and current management, but the development of a greater understanding and availability of therapies is needed to ensure patients with lymphedema have greater opportunity for optimal care.

New Insights into the Link Between Melanoma and Obesity

The significant increase in the incidence of obesity represents a global health crisis. Obesity is actually a multi-organ disease affecting the entire organism; hence, skin is no exception. As the functional alterations in the adipose tissue are contributing factors to many diseases, including cancer, recently, the link between the development of melanoma skin cancer and obesity gains increased attention. Besides several other factors, the increase of adipose stromal/stem cells (ASCs) impacts cancer progression. Moreover, increased production of cytokines and growth factors done by ASCs induces tumorigenesis and metastasis. The chronic inflammatory state that is sustained by this metabolic imbalance favors skin malignancies, melanoma included. Cutaneous melanoma, as an aggressive skin cancer, has both intrinsic and extrinsic risk factors where sun exposure and lifestyles are the main environmental factors inducing this skin cancer. With the advent of recent targeted and immune-based therapies in melanoma, the link between obesity and the efficacy of these therapies in melanoma remains controversial. A recent molecular relationship between the melanocortin pathway appending to both melanin synthesis and obesity was established. The biology of adipokines, molecules secreted by the adipose tissue, is linked to inflammation, and their molecular pathways can be involved in angiogenesis, migration, invasion, and proliferation of melanoma cells. In melanoma cells, among the most noticeable metabolic reprogramming characteristics is an increased rate of lipid synthesis. Lipid mediators impact classical oncogenic pathways, affecting melanoma progression. The chapter will tackle also the practical implications for melanoma prevention and treatment, namely, how metabolic manipulation can be exploited to overcome immunosuppression and support immune checkpoint blockade efficacy.

New Therapeutic Strategies for Obesity and Its Metabolic Sequelae: Brazilian Cerrado as a Unique Biome

Brazil has several important biomes holding impressive fauna and flora biodiversity. Cerrado being one of the richest ones and a significant area in the search for new plant-based products, such as foods, cosmetics, and medicines. The therapeutic potential of Cerrado plants has been described by several studies associating ethnopharmacological knowledge with phytochemical compounds and therapeutic effects. Based on this wide range of options, the Brazilian population has been using these medicinal plants (MP) for centuries for the treatment of various health conditions. Among these, we highlight metabolic diseases, namely obesity and its metabolic alterations from metabolic syndrome to later stages such as type 2 diabetes (T2D). Several studies have shown that adipose tissue (AT) dysfunction leads to proinflammatory cytokine secretion and impaired free fatty acid (FFA) oxidation and oxidative status, creating the basis for insulin resistance and glucose dysmetabolism. In this scenario, the great Brazilian biodiversity and a wide variety of phytochemical compounds make it an important candidate for the identification of pharmacological strategies for the treatment of these conditions. This review aimed to analyze and summarize the current literature on plants from the Brazilian Cerrado that have therapeutic activity against obesity and its metabolic conditions, reducing inflammation and oxidative stress.

Ginkgo biloba extract alleviates fatty liver hemorrhagic syndrome in laying hens via reshaping gut microbiota

BACKGROUND

Ginkgo biloba extract (GBE) is evidenced to be effective in the prevention and alleviation of metabolic disorders, including obesity, diabetes and fatty liver disease. However, the role of GBE in alleviating fatty liver hemorrhagic syndrome (FLHS) in laying hens and the underlying mechanisms remain to be elucidated. Here, we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.

RESULTS

The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet (HFD)-induced FLHS laying hen model by decreasing the levels of TG, TC, ALT and ALP. The lipid accumulation and pathological score of liver were also relieved after GBE treatment. Moreover, GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH, SOD, T-AOC, GSH-PX and reducing MDA, and downregulated the expression of genes related to lipid synthesis (FAS, LXRα, GPAT1, PPARγ and ChREBP1) and inflammatory cytokines (TNF-α, IL-6, TLR4 and NF-κB) in the liver. Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota, particularly elevated the abundance of Megasphaera in the cecum. Meanwhile, targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs, acetate and propionate, which were positively correlated with the GBE-enriched gut microbiota. Finally, we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation (FMT).

CONCLUSIONS

We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota. Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.

[Obesity and secondary lymphedema]

Obesity causes all types of lymphedema to deteriorate. Obesity-associated lymphedema is by now the most frequent secondary lymphedema and constitutes an entity in its own right. Obesity and its comorbidities, due to mechanical and inflammatory effects, decrease lymphatic transport and create a vicious circle of lymph stasis, local adipogenesis, and fibrosis. The therapeutic strategy must therefore address both lymphedema and obesity and its comorbidities.

Increased Adipocyte Hypertrophy in Patients with Nascent Metabolic Syndrome

Background and Aims: Metabolic Syndrome (MetS), a global problem, predisposes to an increased risk for type 2 diabetes and premature cardiovascular disease. While MetS is associated with central obesity, there is scanty data on adipocyte hypertrophy, increased fat cell size (FCS), in MetS. The aim of this study was to investigate FCS status in adipose tissue (AT) biopsy of patients with nascent MetS without the confounding of diabetes, cardiovascular disease, smoking, or lipid therapy. Methods and Results: Fasting blood and subcutaneous gluteal AT biopsies were obtained in MetS (n = 20) and controls (n = 19). Cardio-metabolic features, FFA levels, hsCRP, and HOMA-IR were significantly increased in patients with MetS. Waist-circumference (WC) adjusted-FCS was significantly increased in patients with MetS and increased with increasing severity of MetS. Furthermore, there were significant correlations between FCS with glucose, HDL-C, and the ratio of TG: HDL-C. There were significant correlations between FCS and FFA, as well as endotoxin and monocyte TLR4 abundance. Additionally, FCS correlated with readouts of NLRP3 Inflammasome activity. Most importantly, FCS correlated with markers of fibrosis and angiogenesis. Conclusions: In conclusion, in patients with nascent MetS, we demonstrate WC-adjusted increase in FCS from gluteal adipose tissue which correlated with cellular inflammation, fibrosis, and angiogenesis. While these preliminary observations were in gluteal fat, future studies are warranted to confirm these findings in visceral and other fat depots.

Subcutaneous Adipose Tissue Edema in Lipedema Revealed by Noninvasive 3T MR Lymphangiography

BACKGROUND

Lipedema exhibits excessive lower-extremity subcutaneous adipose tissue (SAT) deposition, which is frequently misidentified as obesity until lymphedema presents. MR lymphangiography may have relevance to distinguish lipedema from obesity or lymphedema.

HYPOTHESIS

Hyperintensity profiles on 3T MR lymphangiography can identify distinct features consistent with SAT edema in participants with lipedema.

STUDY TYPE

Prospective cross-sectional study.

SUBJECTS

Participants (48 females, matched for age [mean = 44.8 years]) with lipedema (n = 14), lipedema with lymphedema (LWL, n = 12), cancer treatment-related lymphedema (lymphedema, n = 8), and controls without these conditions (n = 14).

FIELD STRENGTH/SEQUENCE

3T MR lymphangiography (nontracer 3D turbo-spin-echo).

ASSESSMENT

Review of lymphangiograms in lower extremities by three radiologists was performed independently. Spatial patterns of hyperintense signal within the SAT were scored for extravascular (focal, diffuse, or not apparent) and vascular (linear, dilated, or not apparent) image features.

STATISTICAL TESTS

Interreader reliability was computed using Fleiss Kappa. Fisher's exact test was used to evaluate the proportion of image features between study groups. Multinomial logistic regression was used to assess the relationship between image features and study groups. The odds ratio (OR) and 95% confidence interval (CI) of SAT extravascular and vascular features was reported in groups compared to lipedema. The threshold of statistical significance was P < 0.05.

RESULTS

Reliable agreement was demonstrated between three independent, blinded reviewers (P < 0.001). The frequency of SAT hyperintensities in participants with lipedema (36% focal, 36% diffuse), LWL (42% focal, 33% diffuse), lymphedema (62% focal, 38% diffuse), and controls (43% focal, 0% diffuse) was significantly distinct. Compared with lipedema, SAT hyperintensities were less frequent in controls (focal: OR = 0.63, CI = 0.11-3.41; diffuse: OR = 0.05, CI = 0.00-1.27), similar in LWL (focal: OR = 1.29, CI = 0.19-8.89; diffuse: OR = 1.05, CI = 0.15-7.61), and more frequent in lymphedema (focal: OR = 9.00, CI = 0.30-274.12; diffuse: OR = 5.73, CI = 0.18-186.84).

DATA CONCLUSION

Noninvasive MR lymphangiography identifies distinct signal patterns indicating SAT edema and lymphatic load in participants with lipedema.

EVIDENCE LEVEL

1 TECHNICAL EFFICACY: Stage 1.

Increased adipose tissue lymphatic vessel density inhibits thermogenesis through elevated neurotensin levels

During cold exposure, white adipose tissue can remodel to dissipate energy as heat under cold similar to thermogenic brown adipose tissue. This "browning" and the regulation of body temperature is under the control of neural and hormonal signaling. It was recently discovered that neurotensin, a small neuropeptide, not only acts to inhibit thermogenesis, but also that lymphatic vessels may be a surprisingly potent source of neurotensin production. We hypothesized that the induction of adipose tissue lymphangiogenesis would therefore increase tissue neurotensin levels and impair thermogenesis. Methods: We utilized AdipoVD mice that have inducible expression of vascular endothelial growth factor (VEGF)-D, a potent lymphangiogenic stimulator, specifically in adipose tissue. Overexpression of VEGF-D induced significant lymphangiogenesis in both white and brown adipose tissues of AdipoVD mice. Results: Obese Adipo-VD mice demonstrated no differences in adipose morphology or browning under room temperature conditions compared to controls but did express significantly higher levels of neurotensin in their adipose tissues. Upon acute cold exposure, AdipoVD mice were markedly cold intolerant; inhibition of neurotensin signaling ameliorated this cold intolerance as AdipoVD mice were then able to maintain body temperature on cold challenge equivalent to their littermates. Conclusion: In total, these data demonstrate that adipose tissue lymphatic vessels are a potent paracrine source of neurotensin and that lymphangiogenesis therefore impairs the tissues' thermogenic ability.

Lipedema: Insights into Morphology, Pathophysiology, and Challenges

Lipedema is an adipofascial disorder that almost exclusively affects women. Lipedema leads to chronic pain, swelling, and other discomforts due to the bilateral and asymmetrical expansion of subcutaneous adipose tissue. Although various distinctive morphological characteristics, such as the hyperproliferation of fat cells, fibrosis, and inflammation, have been characterized in the progression of lipedema, the mechanisms underlying these changes have not yet been fully investigated. In addition, it is challenging to reduce the excessive fat in lipedema patients using conventional weight-loss techniques, such as lifestyle (diet and exercise) changes, bariatric surgery, and pharmacological interventions. Therefore, lipedema patients also go through additional psychosocial distress in the absence of permanent treatment. Research to understand the pathology of lipedema is still in its infancy, but promising markers derived from exosome, cytokine, lipidomic, and metabolomic profiling studies suggest a condition distinct from obesity and lymphedema. Although genetics seems to be a substantial cause of lipedema, due to the small number of patients involved in such studies, the extrapolation of data at a broader scale is challenging. With the current lack of etiology-guided treatments for lipedema, the discovery of new promising biomarkers could provide potential solutions to combat this complex disease. This review aims to address the morphological phenotype of lipedema fat, as well as its unclear pathophysiology, with a primary emphasis on excessive interstitial fluid, extracellular matrix remodeling, and lymphatic and vasculature dysfunction. The potential mechanisms, genetic implications, and proposed biomarkers for lipedema are further discussed in detail. Finally, we mention the challenges related to lipedema and emphasize the prospects of technological interventions to benefit the lipedema community in the future.

Dibutyl phthalate promotes angiogenesis in EA.hy926 cells through estrogen receptor-dependent activation of ERK1/2, PI3K-Akt, and NO signaling pathways

Dibutyl phthalate (DBP) is an endocrine disruptor that has been widely used in various products of human use. DBP exposure has been associated with reproductive and cardiovascular diseases and metabolic disorders. Although dysfunction of the vascular endothelium is responsible for many cardiovascular and metabolic diseases, little is known about the effects of DBP on human endothelium. In this study, we investigated the effect of three concentrations of DBP (10^-6, 10^-5, and 10^-4 M) on angiogenesis in human endothelial cell (EC) line EA.hy926 after acute exposure. Tube formation assay was used to investigate in vitro angiogenesis, whereas qRT-PCR was employed to measure mRNA expression. The effect of DBP on extracellular signal-regulated kinase 1/2 (ERK1/2), phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt), and endothelial nitric oxide (NO) synthase (eNOS) activation was examined using Western blotting, whereas the Griess method was used to assess NO production. Results show that the 24-h-long exposure to 10^-4 M DBP increased endothelial tube formation, which was prevented by addition of U0126 (ERK1/2 inhibitor), wortmannin (PI3K-Akt inhibitor), and l-NAME (NOS inhibitor). Short exposure to 10^-4 M DBP (from 15 to 120 min) phosphorylated ERK1/2, Akt, and eNOS in different time points and increased NO production after 24 and 48 h of exposure. Application of nuclear estrogen receptor (ER) and G protein-coupled ER (GPER) inhibitors ICI 182,780 and G-15, respectively, abolished the DBP-mediated ERK1/2, Akt, and eNOS phosphorylation and increase in NO production. In this study, we report for the first time that DBP exerts a pro-angiogenic effect on human vascular ECs and describe the molecular mechanism involving ER- and GPER-dependent activation of ERK1/2, PI3K-Akt, and NO signaling pathways.

Current Mechanistic Understandings of Lymphedema and Lipedema: Tales of Fluid, Fat, and Fibrosis

Lymphedema and lipedema are complex diseases. While the external presentation of swollen legs in lower-extremity lymphedema and lipedema appear similar, current mechanistic understandings of these diseases indicate unique aspects of their underlying pathophysiology. They share certain clinical features, such as fluid (edema), fat (adipose expansion), and fibrosis (extracellular matrix remodeling). Yet, these diverge on their time course and known molecular regulators of pathophysiology and genetics. This divergence likely indicates a unique route leading to interstitial fluid accumulation and subsequent inflammation in lymphedema versus lipedema. Identifying disease mechanisms that are causal and which are merely indicative of the condition is far more explored in lymphedema than in lipedema. In primary lymphedema, discoveries of genetic mutations link molecular markers to mechanisms of lymphatic disease. Much work remains in this area towards better risk assessment of secondary lymphedema and the hopeful discovery of validated genetic diagnostics for lipedema. The purpose of this review is to expose the distinct and shared (i) clinical criteria and symptomatology, (ii) molecular regulators and pathophysiology, and (iii) genetic markers of lymphedema and lipedema to help inform future research in this field.

Early postnatal exposure of rat pups to methylglyoxal induces oxidative stress, inflammation and dysmetabolism at adulthood

This work aimed to investigate the effects of early progeny exposure to methylglyoxal (MG), programming for metabolic dysfunction and diabetes-like complications later in life. At delivery (PN1), the animals were separated into two groups: control group (CO), treated with saline, and MG group, treated with MG (20 mg/kg of BW; i.p.) during the first 2 weeks of the lactation period. In vivo experiments and tissue collection were done at PN90. Early MG exposure decreased body weight, adipose tissue, liver and kidney weight at adulthood. On the other hand, MG group showed increased relative food intake, blood fructosamine, blood insulin and HOMA-IR, which is correlated with insulin resistance. Besides, MG-treated animals presented dyslipidaemia, increased oxidative stress and inflammation. Likewise, MG group showed steatosis and perivascular fibrosis in the liver, pancreatic islet hypertrophy, increased glomerular area and pericapsular fibrosis, but reduced capsular space. This study shows that early postnatal exposure to MG induces oxidative stress, inflammation and fibrosis markers in pancreas, liver and kidney, which are related to metabolic dysfunction features. Thus, nutritional disruptors during lactation period may be an important risk factor for metabolic alterations at adulthood.

Type 2 Innate Lymphoid Cells: Protectors in Type 2 Diabetes

Type 2 innate lymphoid cells (ILC2) are the innate counterparts of Th2 cells and are critically involved in the maintenance of homeostasis in a variety of tissues. Instead of expressing specific antigen receptors, ILC2s respond to external stimuli such as alarmins released from damage. These cells help control the delicate balance of inflammation in adipose tissue, which is a determinant of metabolic outcome. ILC2s play a key role in the pathogenesis of type 2 diabetes mellitus (T2DM) through their protective effects on tissue homeostasis. A variety of crosstalk takes place between resident adipose cells and ILC2s, with each interaction playing a key role in controlling this balance. ILC2 effector function is associated with increased browning of adipose tissue and an anti-inflammatory immune profile. Trafficking and maintenance of ILC2 populations are critical for tissue homeostasis. The metabolic environment and energy source significantly affect the number and function of ILC2s in addition to affecting their interactions with resident cell types. How ILC2s react to changes in the metabolic environment is a clear determinant of the severity of disease. Treating sources of metabolic instability via critical immune cells provides a clear avenue for modulation of systemic homeostasis and new treatments of T2DM.

Predictors for Prolonged Drain Use Following Autologous Breast Reconstruction

BACKGROUND

 Surgical drains are routinely used following autologous reconstruction, but are often cited as the leading cause of peri-operative discomfort. This study defined routine drain use duration and assessed the risk factors for prolonged breast and abdominal drain use during microvascular breast reconstruction, measures which have never previously been defined.

METHODS

 Patients who underwent an abdominal microvascular free flap were included. Demographics, comorbidities, and operation-related characteristics were retrospectively collected in a prospectively maintained database. Statistical analysis utilized chi-square independent t-test, and linear regression analyses.

RESULTS

 One hundred forty-nine patients comprising 233 breast flaps were included. Average breast and abdominal drain duration were 12.9 ± 3.9 and 17.7 ± 8.2 days, respectively. Prolonged breast and abdominal drain duration were defined as drain use beyond the 75^th percentile at 14 and 19 days, respectively. Multivariable regression revealed hypertension was associated with an increased breast drain duration by 1.4 days (p = 0.024), axillary dissection with 1.7 days (p = 0.026), African-American race with 3.1 days (p < 0.001), Hispanic race with 1.6 days (p = 0.029), return to the OR with 3.2 days (p = 0.004), and each point increase in BMI with 0.1 days (p = 0.028). For abdominal drains, each point increase in BMI was associated with an increased abdominal drain duration by 0.3 days (p = 0.011), infection with 14.4 days (p < 0.001), and return to the OR with 5.7 days (p = 0.007).

CONCLUSION

 Elevated BMI, hypertension, and axillary dissection increase risk for prolonged breast drain requirement in autologous reconstruction. African-American and Hispanic populations experience prolonged breast drain requirement after controlling for other factors, warranting further study.

Ethanol-induced lymphatic endothelial cell permeability via MAP-kinase regulation

Chronic alcohol alters the immune system enhancing the susceptibility to inflammation, bacterial, and viral infections in alcohol users. We have shown that alcohol causes increased permeability of mesenteric lymphatic vessels in alcohol-fed rats. The mechanisms of alcohol-induced lymphatic leakage are unknown. Endothelial cell monolayer permeability is controlled by junctional proteins complexes called tight junctions (TJ) and adherens junctions (AJ), and each can be regulated by MAPK activation. We hypothesize that ethanol induces lymphatic endothelial cell (LEC) permeability via disruption of LEC TJ through MAPK activation. An in vitro model of rat LECs was used. Ethanol-supplemented medium was added at concentrations of 0, 25, and 50 mM to confluent cells. Resistance-based barrier function, transwell permeability, cell viability, TJ, AJ, and MAPK protein activity, TJ and AJ gene expressions, and the role of p38 MAPK in barrier function regulation were measured. Ethanol increased the permeability of LECs compared to controls that was not associated with decreased cell viability. LECs treated with 50 mM ethanol showed an increase in phosphorylated levels of p38. No significant changes in TJ and AJ gene or protein expressions were observed after ethanol treatment. p38 inhibition prevented ethanol-induced increases in permeability. These findings suggest that p38 may play a role in the regulation of ethanol-induced LEC permeability, but altered permeability may not be associated with decreased TJ or AJ protein expression. Further investigation into junctional protein localization is needed to better understand the effects of ethanol on lymphatic endothelial cell-to-cell contacts and hyperpermeability.

Lymphatic dysfunction in advanced cirrhosis: Contextual perspective and clinical implications

The lymphatic system plays a very important role in body fluid homeostasis, adaptive immunity, and the transportation of lipid and waste products. In patients with liver cirrhosis, capillary filtration markedly increases, primarily due to a rise in hydrostatic pressure, leading to enhanced production of lymph. Initially, lymphatic vasculature expansion helps to prevent fluid from accumulating by returning it back to the systemic circulation. However, the lymphatic functions become compromised with the progression of cirrhosis and, consequently, the lymphatic compensatory mechanism gets overwhelmed, contributing to the development and eventual worsening of ascites and edema. Neurohormonal changes, low-grade chronic inflammation, and compounding effects of predisposing factors such as old age, obesity, and metabolic syndrome appear to play a significant role in the lymphatic dysfunction of cirrhosis. Sustained portal hypertension can contribute to the development of intestinal lymphangiectasia, which may rupture into the intestinal lumen, resulting in the loss of protein, chylomicrons, and lymphocyte, with many clinical consequences. Rarely, due to high pressure, the rupture of the subserosal lymphatics into the abdomen results in the formation of chylous ascites. Despite being highly significant, lymphatic dysfunctions in cirrhosis have largely been ignored; its mechanistic pathogenesis and clinical implications have not been studied in depth. No recommendation exists for the diagnostic evaluation and therapeutic strategies, with respect to lymphatic dysfunction in patients with cirrhosis. This article discusses the perspectives and clinical implications, and provides insights into the management strategies for lymphatic dysfunction in patients with cirrhosis.

Lymphstase und Fettgewebshypertrophie – Pathophysiologische Zusammenhänge und therapeutische Optionen

Angeborene oder erworbene, iatrogene, traumatische oder postinfektiöse Störungen des Lymphabflusses führen aufgrund der Lymphstase im Laufe der Zeit zu Gewebeveränderungen wie Fibrosierung und vermehrter lokaler Fettgewebebildung. Häufig kommt es hierdurch zu einer extremen Volumenzunahme der betroffenen Extremität, die nicht durch das Lymphödem allein, sondern vor allem durch die massive Fettgewebshypertrophie bedingt ist. Lymphgefäße und Lymphknoten sind immer in Fettgewebe eingebettet. Dieses perilymphatische Fettgewebe ist essenziell für die lymphatische wie auch immunologische Funktion des Lymphsystems, da das Lymphsystem Fettsäuren als primäre Energiequelle nützt. Kommt es nach Lymphadenektomie und/oder Unterbrechung von Lymphgefäßen zur Lymphstase in der betroffenen Extremität, signalisiert diese einen gesteigerten Energiebedarf für die notwendige Immunantwort und die chronische Inflammation verursacht eine Überstimulation der Fettgewebsproliferation, um ausreichend Energie zur Verfügung stellen zu können. In der Folge kommt es zu weiteren pathophysiologischen Veränderungen, die die Drainagefunktion und damit die Lymphstase weiter verschlechtern. Es hat sich ein Circulus vitiosus aus Lymphstase, Fettgewebsproliferation und Fibrosierung entwickelt.

Da die komplexe Entstauungstherapie diesen Zustand allein nicht wesentlich verbessern kann, kommen therapeutisch zusätzliche gewebereduzierende operative Verfahren, in erster Linie die Liposuktion, ggf. in Kombination mit mikrochirurgischen Operationstechniken, zum Einsatz.

Pyridoxamine and Caloric Restriction Improve Metabolic and Microcirculatory Abnormalities in Rats with Non-Alcoholic Fatty Liver Disease

INTRODUCTION

This study aims to examine the effect of a diet intervention and pyridoxamine (PM) supplementation on hepatic microcirculatory and metabolic dysfunction in nonalcoholic fatty liver disease (NAFLD).

METHODS

NAFLD in Wistar rats was induced with a high-fat diet for 20 weeks (NAFLD 20 weeks), and control animals were fed with a standard diet. The NAFLD diet intervention group received the control diet between weeks 12 and 20 (NAFLD 12 weeks), while the NAFLD 12 weeks + PM group also received PM. Fasting blood glucose (FBG) levels, body weight (BW), visceral adipose tissue (VAT), and hepatic microvascular blood flow (HMBF) were evaluated at the end of the protocol.

RESULTS

The NAFLD group exhibited a significant increase in BW and VAT, which was prevented by the diet intervention, irrespective of PM treatment. The FBG was elevated in the NAFLD group, and caloric restriction improved this parameter, although additional improvement was achieved by PM. The NAFLD group displayed a 31% decrease in HMBF, which was partially prevented by caloric restriction and completely prevented when PM was added. HMBF was negatively correlated to BW, FBG, and VAT content.

CONCLUSION

PM supplementation in association with lifestyle modifications could be an effective intervention for metabolic and hepatic vascular complications.

Flavonoids as antiobesity agents: A review

Obesity is a global health problem that affects all age groups in both developing and developed countries. In recent years, the prevalence of overweight and obesity has reached pandemic levels, resulting in a dramatic increase in the incidence of various comorbidities, such as cardiovascular diseases, type 2 diabetes, and cancer, consequently leading to massive health and socioeconomic burdens. Together with lifestyle changes, antiobesity pharmacotherapy is gaining momentum as an adjunctive treatment. However, the available pharmacological approaches have limited use owing to either significant adverse effects or low efficacy. Over the years, natural products have been an important source of lead compounds for drug discovery. Among these, flavonoids are associated with important biological effects and health-promoting activities. In this review, we discuss the modulatory effects of flavonoids on obesity and their potential mechanisms of action. The literature strongly suggests that most common flavonoids demonstrate a pronounced effect on obesity as shown by their ability to lower body weight, fat mass, and plasma triglycerides/cholesterol, both in in vitro and in vivo models. The impact of flavonoids on obesity can be observed through different mechanisms: reducing food intake and fat absorption, increasing energy expenditure, modulating lipid metabolism, or regulating gut microbiota profile. A better understanding of the known antiobesity mechanisms of flavonoids will enable their potential use to treat this medical condition. Therefore, this review focuses on the putative biological mechanisms through which flavonoids may prevent or treat obesity and highlights new perspectives on future pharmacological use.

SP prevents T2DM complications by immunomodulation

Type 2 diabetic mellitus (T2DM) is characterized by systemic inflammation and insulin resistance due to obesity, and this leads to critical complications, including retinopathy and nephropathy. This study explored the therapeutic effect of substance-p (SP), a neuropeptide, on T2DM progression and its complications. To examine whether SP affects glucose metabolism, lipid metabolism, systemic inflammation, and retinopathy, Otsuka Long-Evans Tokushima Fatty rats (OLETF, 27 weeks old) with chronic inflammation, obesity, and impaired bone marrow stem cell pool was selected. SP was intravenously injected and its effect was evaluated at 2 and 4 weeks after the SP injection. OLETF had typical symptoms of T2DM, including obesity, chronic inflammation, and poor glycemic control. However, SP treatment inhibited the body-weight gain and reduced circulating levels of free fatty acid, cholesterol, and triglyceride, ameliorating the obese environment. SP could suppress inflammation and rejuvenate bone marrow stem cell in OLETF rats. SP-mediated metabolic/immunological change could resolve hyperglycemia and insulin resistance. Histopathological analysis confirmed that SP treatment alleviated the dysfunction of target tissue with insulin resistance. OLETF rats have retinal damage from 27 weeks of age, which was reliably aggravated at 31 weeks. However, SP treatment could restore the damaged retina, sustaining its structure similarly to that of non-diabetic rats. In conclusion, systemic application of SP is capable contribute to the inhibition of the progression of T2DM and diabetic retinopathy.

Quantification of Fat Concentration and Vascular Response in Brown and White Adipose Tissue of Rats by Spectral CT Imaging

Objective

The purpose of the study was to non-invasively characterize and discriminate brown adipose tissue (BAT) from white adipose tissue (WAT) in rats using spectral computed tomography (CT) with histological validation.

Materials and Methods

A lipid-containing phantom (lipid fractions from 0% to 100%) was imaged with spectral CT. An in vivo, non-enhanced spectral CT scan was performed on 24 rats, and fat concentrations of BAT and WAT were measured. The rats were randomized to receive intraperitoneal treatment with norepinephrine (NE) (n = 12) or saline (n = 12). Non-enhanced and enhanced spectral CT scans were performed after treatment to measure the elevation of iodine in BAT and WAT. The BAT/aorta and WAT/aorta ratios were calculated and compared, after which isolated BAT and WAT samples were subjected to histological and uncoupling protein 1 (UCP1) analyses.

Results

The ex-vivo phantom study showed excellent linear fit between measured fat concentration and the known gravimetric reference standard (r² = 0.996). In vivo, BAT had significantly lower fat concentration than WAT (p < 0.001). Compared to the saline group, the iodine concentration of BAT increased significantly (p < 0.001) after injection of NE, while the iodine concentration of WAT only changed slightly. The BAT/aorta ratio also increased significantly after exposure to NE compared to the saline group (p < 0.001). Histological and UCP1 expression analyses supported the spectral CT imaging results.

Conclusion

The study consolidates spectral CT as a new approach for non-invasive imaging of BAT and WAT. Quantitative analyses of BAT and WAT by spectral CT revealed different characteristics and pharmacologic activations in the two types of adipose tissue.

The Role of Exosomes in the Crosstalk between Adipocytes and Liver Cancer Cells

Exosomes are membrane-bound extracellular vesicles (EVs) that transport bioactive materials between cells and organs. The cargo delivered by exosomes can alter a wide range of cellular responses in recipient cells and play an important pathophysiological role in human cancers. In hepatocellular carcinoma (HCC), for example, adipocyte- and tumor-secreted factors contained in exosomes contribute to the creation of a chronic inflammatory state, which contributes to disease progression. The exosome-mediated crosstalk between adipocytes and liver cancer cells is a key aspect of a dynamic tumor microenvironment. In this review, we summarize the role of increased adiposity and the role of adipocyte-derived exosomes (AdExos) and HCC-derived exosomes (HCCExos) in the modulation of HCC progression. We also discuss recent advances regarding how malignant cells interact with the surrounding adipose tissue and employ exosomes to promote a more aggressive phenotype.

Systems Biology Will Direct Vascular-Targeted Therapy for Obesity

Healthy adipose tissue expansion and metabolism during weight gain require coordinated angiogenesis and lymphangiogenesis. These vascular growth processes rely on the vascular endothelial growth factor (VEGF) family of ligands and receptors (VEGFRs). Several studies have shown that controlling vascular growth by regulating VEGF:VEGFR signaling can be beneficial for treating obesity; however, dysregulated angiogenesis and lymphangiogenesis are associated with several chronic tissue inflammation symptoms, including hypoxia, immune cell accumulation, and fibrosis, leading to obesity-related metabolic disorders. An ideal obesity treatment should minimize adipose tissue expansion and the advent of adverse metabolic consequences, which could be achieved by normalizing VEGF:VEGFR signaling. Toward this goal, a systematic investigation of the interdependency of vascular and metabolic systems in obesity and tools to predict personalized treatment ranges are necessary to improve patient outcomes through vascular-targeted therapies. Systems biology can identify the critical VEGF:VEGFR signaling mechanisms that can be targeted to regress adipose tissue expansion and can predict the metabolic consequences of different vascular-targeted approaches. Establishing a predictive, biologically faithful platform requires appropriate computational models and quantitative tissue-specific data. Here, we discuss the involvement of VEGF:VEGFR signaling in angiogenesis, lymphangiogenesis, adipogenesis, and macrophage specification – key mechanisms that regulate adipose tissue expansion and metabolism. We then provide useful computational approaches for simulating these mechanisms, and detail quantitative techniques for acquiring tissue-specific parameters. Systems biology, through computational models and quantitative data, will enable an accurate representation of obese adipose tissue that can be used to direct the development of vascular-targeted therapies for obesity and associated metabolic disorders.

Self-perception of overweight and obesity: A review of mental and physical health outcomes

The obesity crisis is one of the largest public health challenges of the 21st century. Population‐level adiposity has increased dramatically in recent times, and people not recognizing that they have overweight or obesity is now common. It has been widely assumed that not recognizing oneself as having overweight is detrimental to weight management and long‐term health. Here, diverse research is reviewed that converges on the counterintuitive conclusion that not recognizing oneself as having overweight is actually associated with more favourable physical and mental health outcomes than recognizing oneself as having overweight. Drawing on existing models in social psychology and weight stigma research, an explanatory model of the health effects of self‐perception of overweight is outlined. This model proposes that self‐perception of overweight triggers social rejection concerns and the internalization of weight stigma, which in turn induce psychological distress and negatively impact health‐promoting lifestyle behaviours. How self‐perception of overweight may in part explain progression from overweight to obesity, and the public health implications of self‐perception of overweight and obesity are also discussed.

New role for ceramide in hypoxia and insulin resistance

Ceramides are significant metabolic products of sphingolipids in lipid metabolism and are associated with insulin resistance and hepatic steatosis. In chronic inflammatory pathological conditions, hypoxia occurs, the metabolism of ceramide changes, and insulin resistance arises. Hypoxia-inducible factors (HIFs) are a family of transcription factors activated by hypoxia. In hypoxic adipocytes, HIF-1α upregulates pla2g16 (a novel HIF-1α target gene) gene expression to activate the NLRP3 inflammasome pathway and stimulate insulin resistance, and adipocyte-specific Hif1a knockout can ameliorate homocysteine-induced insulin resistance in mice. The study on the HIF-2α—NEU3—ceramide pathway also reveals the role of ceramide in hypoxia and insulin resistance in obese mice. Under obesity-induced intestinal hypoxia, HIF-2α increases the production of ceramide by promoting the expression of the gene Neu3 encoding sialidase 3, which is a key enzyme in ceramide synthesis, resulting in insulin resistance in high-fat diet-induced obese mice. Moreover, genetic and pathophysiologic inhibition of the HIF-2α—NEU3—ceramide pathway can alleviate insulin resistance, suggesting that these could be potential drug targets for the treatment of metabolic diseases. Herein, the effects of hypoxia and ceramide, especially in the intestine, on metabolic diseases are summarized.

The Role of Lymphatic Vascular Function in Metabolic Disorders

In addition to its roles in the maintenance of interstitial fluid homeostasis and immunosurveillance, the lymphatic system has a critical role in regulating transport of dietary lipids to the blood circulation. Recent work within the past two decades has identified an important relationship between lymphatic dysfunction and patients with metabolic disorders, such as obesity and type 2 diabetes, in part characterized by abnormal lipid metabolism and transport. Utilization of several genetic mouse models, as well as non-genetic models of diet-induced obesity and metabolic syndrome, has demonstrated that abnormal lymphangiogenesis and poor collecting vessel function, characterized by impaired contractile ability and perturbed barrier integrity, underlie lymphatic dysfunction relating to obesity, diabetes, and metabolic syndrome. Despite the progress made by these models, the contribution of the lymphatic system to metabolic disorders remains understudied and new insights into molecular signaling mechanisms involved are continuously developing. Here, we review the current knowledge related to molecular mechanisms resulting in impaired lymphatic function within the context of obesity and diabetes. We discuss the role of inflammation, transcription factor signaling, vascular endothelial growth factor-mediated signaling, and nitric oxide signaling contributing to impaired lymphangiogenesis and perturbed lymphatic endothelial cell barrier integrity, valve function, and contractile ability in collecting vessels as well as their viability as therapeutic targets to correct lymphatic dysfunction and improve metabolic syndromes.

An adipose tissue galectin controls endothelial cell function via preferential recognition of 3-fucosylated glycans

Upon overnutrition, adipocytes activate a homeostatic program to adjust anabolic pressure. An inflammatory response enables adipose tissue (AT) expansion with concomitant enlargement of its capillary network, and reduces energy storage by increasing insulin resistance. Galectin-12 (Gal-12), an endogenous lectin preferentially expressed in AT, plays a key role in adipocyte differentiation, lipolysis, and glucose homeostasis. Here, we reveal biochemical and biophysical determinants of Gal-12 structure, including its preferential recognition of 3-fucosylated structures, a unique feature among members of the galectin family. Furthermore, we identify a previously unanticipated role for this lectin in the regulation of angiogenesis within AT. Gal-12 showed preferential localization within the inner side of lipid droplets, and its expression was upregulated under hypoxic conditions. Through glycosylation-dependent binding to endothelial cells, Gal-12 promoted in vitro angiogenesis. Moreover, analysis of in vivo AT vasculature showed reduced vascular networks in Gal-12-deficient (Lgals12^-/-) compared to wild-type mice, supporting a role for this lectin in AT angiogenesis. In conclusion, this study unveils biochemical, topological, and functional features of a hypoxia-regulated galectin in AT, which modulates endothelial cell function through recognition of 3-fucosylated glycans. Thus, glycosylation-dependent programs may control AT homeostasis by modulating endothelial cell biology with critical implications in metabolic disorders and inflammation.

Extracellular Matrix Remodeling of Adipose Tissue in Obesity and Metabolic Diseases

The extracellular matrix (ECM) is a network of different proteins and proteoglycans that controls differentiation, migration, repair, survival, and development, and it seems that its remodeling is required for healthy adipose tissue expansion. Obesity drives an excessive lipid accumulation in adipocytes, which provokes immune cells infiltration, fibrosis (an excess of deposition of ECM components such as collagens, elastin, and fibronectin) and inflammation, considered a consequence of local hypoxia, and ultimately insulin resistance. To understand the mechanism of this process is a challenge to treat the metabolic diseases. This review is focused at identifying the putative role of ECM in adipose tissue, describing its structure and components, its main tissue receptors, and how it is affected in obesity, and subsequently the importance of an appropriate ECM remodeling in adipose tissue expansion to prevent metabolic diseases.

Obesity and its cardiovascular effects

Obesity is described in terms of body fat percentage or body mass index (BMI), despite the fact that these measures do not give full insight about the body fat distribution. It is presently a consistently growing universal challenge since it has tripled in the last 10 years, killing approximately 28 million people each year. In this review, we aim to clarify the different results of obesity on the working and physiology of the cardiovascular system and to reveal changes in the obesity "paradox"-a variety of cardiovascular outcomes in typical/overweight people. Central fat build-up in ordinary/overweight populaces has been related to expanded occurrences of myocardial infarction, heart failure, or all-cause mortality when contrasted with the obese populace. These discoveries are additionally clarified as the abundance and prolonged vulnerability to free fatty acids (FFAs) in obesity. This has been believed to cause the myocardial substrate to move from glucose to FFAs digestion, which causes lipid gathering in cardiomyocytes, spilling over to other lean tissues, and prompting a general atherogenic impact. This cardiomyocyte lipid aggregation has been demonstrated to cause insulin resistance and cardiovascular hypertrophy, and to lessen the heart functions in general. There is a proof backing the fact that fat tissue is not only an energy reservoir, it also coordinates hormones and proinflammatory cytokines and deals with the energy transition of the body by putting away abundant lipids in diverse tissues.

Deletion of Robo4 prevents high-fat diet-induced adipose artery and systemic metabolic dysfunction

OBJECTIVE

Accumulating evidence suggests the vascular endothelium plays a fundamental role in the pathophysiology of obesity by regulating the functional status of white adipose and systemic metabolism. Robo4 is expressed specifically in endothelial cells and increases vascular stability and inhibits angiogenesis. We sought to determine the role of Robo4 in modulating cardiometabolic function in response to high-fat feeding.

METHODS

We examined exercise capacity, glucose tolerance, and white adipose tissue artery gene expression, endothelium-dependent dilation (EDD), and angiogenesis in wild type and Robo4 knockout (KO) mice fed normal chow (NC) or a high-fat diet (HFD).

RESULTS

We found Robo4 deletion enhances exercise capacity in NC-fed mice and HFD markedly increased the expression of the Robo4 ligand, Slit2, in white adipose tissue. Deletion of Robo4 increased angiogenesis in white adipose tissue and protected against HFD-induced impairments in white adipose artery vasodilation and glucose intolerance.

CONCLUSIONS

We demonstrate a novel functional role for Robo4 in endothelial cell function and metabolic homeostasis in white adipose tissue, with Robo4 deletion protecting against endothelial and metabolic dysfunction associated with a HFD. Our findings suggest that Robo4-dependent signaling pathways may be a novel target in anti-obesity therapy.

Vascular Endothelial Growth Factor-D (VEGF-D) Overexpression and Lymphatic Expansion in Murine Adipose Tissue Improves Metabolism in Obesity

Obese adipose tissue expansion is an inflammatory process that results in dysregulated lipolysis, increased circulating lipids, ectopic lipid deposition, and systemic insulin resistance. Lymphatic vessels provide a route of fluid, macromolecule, and immune cell clearance, and lymphangiogenesis increases this capability. Indeed, inflammation-associated lymphangiogenesis is critical in resolving acute and chronic inflammation, but it is largely absent in obese adipose tissue. Enhancing adipose tissue lymphangiogenesis could, therefore, improve metabolism in obesity. To test this hypothesis, transgenic mice with doxycycline-inducible expression of murine vascular endothelial growth factor (VEGF)-D under a tightly controlled Tet-On promoter were crossed with adipocyte-specific adiponectin-reverse tetracycline-dependent transactivator mice (Adipo-VD) to stimulate adipose tissue-specific lymphangiogenesis during 16-week high-fat diet-induced obesity. Adipose VEGF-D overexpression induced de novo lymphangiogenesis in murine adipose tissue, and obese Adipo-VD mice exhibited enhanced glucose clearance, lower insulin levels, and reduced liver triglycerides. On β-3 adrenergic stimulation, Adipo-VD mice exhibited more rapid and increased glycerol flux from adipose tissue, suggesting that the lymphatics are a potential route of glycerol clearance. Resident macrophage crown-like structures were scarce and total F4/80⁺ macrophages were reduced in obese Adipo-VD s.c. adipose tissue with evidence of increased immune trafficking from the tissue. Augmenting VEGF-D signaling and lymphangiogenesis specifically in adipose tissue, therefore, reduces obesity-associated immune accumulation and improves metabolic responsiveness.

Periprostatic fat adipokine expression is correlated with prostate cancer aggressiveness in men undergoing radical prostatectomy for clinically localized disease

OBJECTIVES

To investigate the relationship between periprostatic adipose tissue (PPAT) adipokine expression and prostate cancer (PCa) aggressiveness using both pathological features of radical prostatectomy (RP) and multiparametric magnetic resonance imaging ( MRI) variables.

PATIENTS AND METHODS

Sixty-nine men were recruited to assess immunohistochemical expression of tumour necrosis factor (TNF)α and vascular endothelial growth factor (VEGF) of periprostatic fat of RP specimens. Per cent immunopositivity was quantified on scanned slides using the Aperio Positive Pixel Count algorithm for PPAT TNFα, VEGF and androgen receptors. Periprostatic fat volume (PFV) was segmented on contiguous T₁ -weighted axial MRI slices from the level of the prostate base to apex. PFV was normalized to prostate volume (PV) to account for variations in PV (normalized PFV = PFV/PV). MRI quantitative values (K_ep , K_trans and apparent diffusion coefficient) were measured from the PCa primary lesion using Olea Sphere software. Patients were stratified into three groups according to RP Gleason score (GS): ≤6, 7(3 + 4) and ≥7(4 + 3).

RESULTS

The mean rank of VEGF and TNFα was significantly different between the groups [H(2) = 11.038, P = 0.004] and [H(2) = 13.086, P = 0.001], respectively. Patients with stage pT₃ had higher TNFα (18.2 ± 8.95) positivity than patients with stage pT₂ (13.27 ± 10.66; t [67] = -2.03, P = 0.047). TNFα expression significantly correlated with K_trans (ρ = 0.327, P = 0.023). TNFα (P = 0.043), and VEGF (P = 0.02) correlated with high grade PCa (GS ≥ 7) in RP specimens and also correlated significantly with upgrading of GS from biopsy to RP histology.

CONCLUSIONS

The expression levels of TNFα and VEGF on immunostaining significantly correlated with aggressivity of PCa. As biomarkers, these indicate the risk of having high grade PCa in men undergoing RP.

Impaired Adipogenesis and Dysfunctional Adipose Tissue in Human Hypertrophic Obesity

The subcutaneous adipose tissue (SAT) is the largest and best storage site for excess lipids. However, it has a limited ability to expand by recruiting and/or differentiating available precursor cells. When inadequate, this leads to a hypertrophic expansion of the cells with increased inflammation, insulin resistance, and a dysfunctional prolipolytic tissue. Epi-/genetic factors regulate SAT adipogenesis and genetic predisposition for type 2 diabetes is associated with markers of an impaired SAT adipogenesis and development of hypertrophic obesity also in nonobese individuals. We here review mechanisms for the adipose precursor cells to enter adipogenesis, emphasizing the role of bone morphogenetic protein-4 (BMP-4) and its endogenous antagonist gremlin-1, which is increased in hypertrophic SAT in humans. Gremlin-1 is a secreted and a likely important mechanism for the impaired SAT adipogenesis in hypertrophic obesity. Transiently increasing BMP-4 enhances adipogenic commitment of the precursor cells while maintained BMP-4 signaling during differentiation induces a beige/brown oxidative phenotype in both human and murine adipose cells. Adipose tissue growth and development also requires increased angiogenesis, and BMP-4, as a proangiogenic molecule, may also be an important feedback regulator of this. Hypertrophic obesity is also associated with increased lipolysis. Reduced lipid storage and increased release of FFA by hypertrophic SAT are important mechanisms for the accumulation of ectopic fat in the liver and other places promoting insulin resistance. Taken together, the limited expansion and storage capacity of SAT is a major driver of the obesity-associated metabolic complications.

Lymphoedema After Breast Cancer Treatment is Associated With Higher Body Mass Index: A Systematic Review and Meta-Analysis

Background:

Excess body weight has been identified as an important risk factor for lymphoedema following breast cancer treatment, however it remains unclear how much risk increases as weight increases. We conducted a meta-analysis to assess the relationship between body mass index (BMI) and risk of lymphoedema in breast cancer patients, and to estimate the level of risk by BMI category.

Methods:

We conducted a systematic search of all articles published through May 2018 in PubMed and the Cochrane library. Studies that included data on BMI and lymphoedema in breast cancer patients were included in the meta-analysis. We compared risk of lymphoedema in BMI groups as: BMI<25 versus BMI≥25, BMI<25 versus BMI≥30, BMI≥25 to <30 versus BMI≥30, BMI<30 versus BMI≥30, BMI<25 versus BMI≥25 to BMI<30.

Results:

After exclusion of ineligible studies, 57 studies were included in the meta-analysis. The mean difference in BMI between patients with lymphoedema compared to those without lymphoedema was 1.7 (95% CI, 1.3–2.2). Compared to patients with a BMI<25, risk of lymphoedema was higher in those with a BMI >25 to <30 (odds ratio [OR] 1.3; 95% CI, 1.2 to 1.5), a BMI≥25 (OR 1.7; 95% CI, 1.5 to 1.9), or a BMI≥30 (OR 1.9; 95% CI, 1.6 to 2.4). Compared to patients with a BMI of >25 to <30, risk of lymphoedema was higher in patients with a BMI>30 (OR 1.5; 95% CI,1.4 to 1.8).

Conclusion:

Excess body weight is a risk factor for lymphoedema following treatment of breast cancer, with the magnitude of risk increasing across higher categories of BMI.

Dietary Genistein Alleviates Lipid Metabolism Disorder and Inflammatory Response in Laying Hens With Fatty Liver Syndrome

This study investigated the molecular mechanism underlying the effect of dietary genistein (GEN) on fatty liver syndrome (FLS) in laying hens. Hens in the control group (CG) were fed a high-energy and low-choline (HELC) diet to establish the FLS model. The livers of the FLS hens were friable and swollen from hemorrhage. Hepatic steatosis and inflammatory cell infiltration were present around the liver blood vessels. Hens in the low-genistein (LGE) and high-genistein (he) groups were fed GEN at 40 and 400 mg/kg doses, respectively, as supplements to the HELC diet. GEN at 40 mg/kg significantly increased gonadotropin-releasing hormone (GnRH) mRNA expression in the hypothalamus, the serum estrogen (E2) level, and the laying rate, whereas 400 mg/kg of GEN decreased GnRH expression and the laying rate without significantly affecting E2, suggesting that high-dose GEN adversely affected the reproductive performance. Either high- or low-dose GEN treatment could alleviate metabolic disorders and inflammatory responses in FLS hens. GEN significantly decreased the serum ALT, creatinine, triglyceride (TG), total cholesterol (TC), and free fatty acid (FFA) levels. Accordingly, the TG and long-chain fatty acid (LCFA) levels, including long-chain saturated fatty acids (LSFAs) and monounsaturated fatty acids (MUFAs), and the n-6:n-3 polyunsaturated fatty acid (PUFA) ratio in the liver were reduced after the GEN treatments, whereas the levels of C22:0, n-3 family fatty acids, C20:3n6, and C20:4n6 were increased. These results indicated that dietary GEN downregulated the expression of genes related to fatty acid synthesis [sterol regulatory element-binding protein 1 (SREBP1c), liver X receptor alpha (LXRα), fatty acid synthase (FAS), and acetyl coenzyme A synthetase (ACC)] and the fatty acid transporter (FAT). Furthermore, GEN treatments upregulated the transcription of genes related to fatty acid β-oxidation [peroxisome proliferator-activated receptor (PPAR)α, PPARδ, ACOT8, ACAD8, and ACADs] in the liver and reduced PPARγ and AFABP expression in abdominal fat. Dietary GEN alleviated inflammatory cell infiltration in the livers of FLS hens and downregulated TNF-α, IL-6, and IL-1β expression. Moreover, GEN treatment increased SOD activity and decreased malondialdehyde activity in the liver. In conclusion, GEN supplementation in the feed inhibited fatty acid synthesis and enhanced β-oxidation in the liver through the PPAR-ACAD/ACOT and PPAR-LXRα-SREBP1c-ACC/FAS/FAT pathways. Dietary GEN alleviated metabolic disorder and inflammation in the FLS hens by improving the antioxidant capacity and fatty acid profile.

Multiscale Imaging of Brown Adipose Tissue in Living Mice/Rats with Fluorescent Polymer Dots

Brown adipose tissue (BAT) has been identified as a promising target for the treatment of obesity, diabetes, and relevant metabolism disorders because of the adaptive thermogenesis ability of this tissue. Visualizing BAT may provide an essential tool for pathology study, drug screening, and efficacy evaluation. Owing to limitations of current nuclear and magnetic resonance imaging approaches for BAT detection, fluorescence imaging has advantages in large-scale preclinical research on small animals. Here, fast BAT imaging in mice is conducted based on polymer dots as fluorescent probes. As early as 5 min after the intravenous injection of polymer dots, extensive fluorescence is detected in the interscapular BAT and axillar BAT. In addition, axillar and inguinal white adipose tissues (WAT) are recognized. The real-time in vivo behavior of polymer dots in rodents is monitored using the probe-based confocal laser endomicroscopy imaging, and the preferred accumulation in BAT over WAT is confirmed by histological assays. Moreover, the whole study is conducted without a low temperature or pharmaceutical stimulation. The imaging efficacy is verified at the cellular, histological, and whole-body levels, and the present results indicate that fluorescent polymer dots may be a promising tool for the visualization of BAT in living subjects.

Underrated enemy - from nonalcoholic fatty liver disease to cancers of the gastrointestinal tract

Nonalcoholic fatty liver disease (NAFLD) is intrahepatic ectopic lipid deposition which is present despite a lack of other causes of secondary hepatic fat accumulation. It is the most common chronic liver disorder in the welldeveloped countries. NAFLD is a multidisciplinary disease that affects various systems and organs and is inextricably linked to simple obesity, metabolic syndrome, insulin resistance and overt diabetes mellitus type 2. The positive energy balance related to obesity leads to a variety of systemic changes including modified levels of insulin, insulin- like growth factor-1, adipokines, hepatokines and cytokines. It is strongly linked to carcinogenesis and new evidence proves that NAFLD is associated with higher risk of all-cause mortality and cancer-specific mortality among cancer survivors. This article focuses on the association between NAFLD and extrahepatic gastrointestinal tract cancers, aiming to shed light on the pathomechanism of changes leading to the development of tumors.

Lifestyle Modification Group for Lymphedema and Obesity Results in Significant Health Outcomes

This study investigated whether a lifestyle modification program that encouraged a ketogenic diet (KD) for participants with lymphedema and obesity would reduce weight and limb volume and improve quality of life. A total of 12 participants with lymphedema and obesity (mean body mass index = 38.38; SD = 7.02) were enrolled in a lifestyle modification group. The timespan from baseline data collection to 30-day follow-up was 18 weeks. Retention rate was 83.3%. Data were analyzed with repeated-measures ANOVA and Pearson correlation. Participants demonstrated statistically significant improvement in most outcome measures. Mean weight loss was 5.18 kg-F(4, 36) = 11.17; P < .001-or 4.8% of mean baseline weight. The average limb volume reduction was 698.9 ml-F(4, 36) = 9.4; P < .001-and was positively correlated with weight loss (r = 0.8; P = .005). There appeared to be a tendency for participants who used a KD (n = 6) to demonstrate superior results in most outcome measures compared with those who did not use the diet (n = 4), although the sample size of the 2 groups was too small to report definitive results. This lifestyle modification program provided insight into the possible value of a KD for obesity and lymphedema management.

5-Aminoimidazole-4-carboxamide ribonucleotide prevents fat gain following the cessation of voluntary physical activity

NEW FINDINGS

What is the central question of this study? We investigated whether 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) could prevent acute increases in body fat and changes in omental and subcutaneous adipose tissue following the sudden transition from physical activity to physical inactivity. What is the main finding and its importance? AICAR prevented fat gains following the transition from physical activity to inactivity to levels comparable to rats that remained physically active. AICAR and continuous physical activity produced depot-specific changes in cyclin A1 mRNA and protein that were associated with the prevention of fat gain. These findings suggest that targeting AMP-activated protein kinase signalling could oppose rapid adipose mass growth. The transition from physical activity to inactivity is associated with drastic increases in 'catch-up' fat that in turn foster the development of many obesity-associated maladies. We tested whether 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR) treatment would prevent gains in body fat following the sudden transition from a physically active state to an inactive state by locking a voluntary running wheel. Male Wistar rats were either sedentary (SED) or given wheel access for 4 weeks, at which time rats with wheels continued running (RUN), had their wheel locked (WL) or had WL with daily AICAR injection (WL + AICAR) for 1 week. RUN and WL + AICAR prevented gains in body fat compared with SED and WL (P < 0.001). Cyclin A1 mRNA, a marker of cell proliferation, was decreased in omental, but not subcutaneous adipose tissue, in RUN and WL + AICAR compared with SED and WL groups (P < 0.05). Both cyclin A1 mRNA and protein were positively associated with gains in fat mass (P < 0.05). Cyclin A1 mRNA in omental, but not subcutaneous, adipose tissue was negatively correlated with p-AMPK levels (P < 0.05). Differences in fat gain and omental mRNA and protein levels were independent of changes in food intake and in differences in select hypothalamic mRNAs. These findings suggest that AICAR treatment prevents acute gains in adipose tissue following physical inactivity to levels of rats that continuously run, and that together, continuous physical activity and AICAR could, at least initially in these conditions, exert similar inhibitory effects on adipogenesis in a depot-specific manner.

Normalized periprostatic fat MRI measurements can predict prostate cancer aggressiveness in men undergoing radical prostatectomy for clinically localised disease

Periprostatic and pelvic fat have been shown to influence prostate cancer behaviour through the secretion of chemokines and growth factors, acting in a paracrine mode. We have measured periprostatic fat volume (PFV) with normalisation to prostate gland volume on pelvic magnetic resonance imaging (MRI) and have correlated this with grade (Gleason score; GS) and pathological staging (pT) of prostate cancer (PCa) following radical prostatectomy (RP). PFV was determined using a segmentation technique on contiguous T1-weighted axial MRI slices from the level of the prostate base to the apex. The abdominal fat area (AFA) and subcutaneous fat thickness (SFT) were measured using T1-weighted axial slices at the level of the umbilicus and the upper border of the symphysis pubis, respectively. PFV was normalised to prostate volume (PV) to account for variations in PV (NPFV = PFV/PV). Patients were stratified into three risk groups according to post-operative GS: ≤6, 7(3 + 4), and ≥7(4 + 3). NPFV was significantly different between the groups (p = 0.001) and positively correlated with post-operative GS (ρ = 0.294, p < 0.001). There was a difference in NPFV between those with upgrading of GS from 6 post prostatectomy (2.43 ± 0.98; n = 26) compared to those who continued to be low grade (1.99 ± 0.82; n = 17); however, this did not reach statistical significance (p = 0.11).