The Impact of the Adipose Organ Plasticity on Inflammation and Cancer Progression

Interleukin-10 deficiency induces thoracic perivascular adipose tissue whitening and vascular remodeling

Perivascular adipose tissue (PVAT) is an adipose layer, surrounding blood vessels, with a local modulatory role. Interleukin-10 (IL-10) has been shown to modulate vascular tissue. This study aimed to characterize the endogenous role of IL-10 in vascular remodeling, and PVAT phenotyping. Thoracic aortic segments from control (C57BL/6J) and IL-10 knockout (IL-10-/-) male mice were used. Analyzes of aorta/PVAT morphometry, and elastin, collagen and reticulin deposition were performed. Tissue uncoupling protein 1 (UCP1) was accessed by Western blotting. Endogenous absence of IL-10 reduced total PVAT area (p = 0.0310), and wall/lumen ratio (p = 0.0024), whereas increased vascular area and thickness (p < 0.0001). Total collagen deposition was augmented in IL-10-/-, but under polarized light, the reduction of collagen-I (p = 0.0075) and the increase of collagen-III (p = 0.0055) was found, simultaneously with reduced elastic fibers deposition (p = 0.0282) and increased deposition of reticular fibers (p < 0.0001). Adipocyte area was augmented in the IL-10 absence (p = 0.0225), and UCP1 expression was reduced (p = 0.0420). Moreover, relative frequency of white adipose cells and connective tissue was augmented in IL-10-/- (p < 0.0001), added to a reduction in brown adipose cells (p < 0.0001). Altogether, these data characterize aorta PVAT from IL-10-/- as a white-like adipocyte phenotype. Endogenous IL-10 prevents vascular remodeling and favors a brown-like adipocyte phenotype, suggesting a modulatory role for IL-10 in PVAT plasticity.

High Throughput Bioprinting Using Decellularized Adipose Tissue-Based Hydrogels for 3D Breast Cancer Modeling

3D bioprinting allows rapid automated fabrication and can be applied for high throughput generation of biomimetic constructs for in vitro drug screening. Decellularized extracellular matrix (dECM) hydrogel is a popular biomaterial choice for tissue engineering and studying carcinogenesis as a tumor microenvironmental mimetic. This study proposes a method for high throughput bioprinting with decellularized adipose tissue (DAT) based hydrogels for 3D breast cancer modeling. A comparative analysis of decellularization protocol using detergent-based and detergent-free decellularization methods for caprine-origin adipose tissue is performed, and the efficacy of dECM hydrogel for 3D cancer modeling is assessed. Histological, biochemical, morphological, and biological characterization and analysis showcase the cytocompatibility of DAT hydrogel. The rheological property of DAT hydrogel and printing process optimization is assessed to select a bioprinting window to attain 3D breast cancer models. The bioprinted tissues are characterized for cellular viability and tumor cell-matrix interactions. Additionally, an approach for breast cancer modeling is shown by performing rapid high throughput bioprinting in a 96-well plate format, and in vitro drug screening using 5-fluorouracil is performed on 3D bioprinted microtumors. The results of this study suggest that high throughput bioprinting of cancer models can potentially have downstream clinical applications like multi-drug screening platforms and personalized disease models.

White adipose tissue, a novel antirheumatic target: Clues from its secretory capability and adipectomy-based therapy

BACKGROUND AND PURPOSE

White adipose tissue (WAT) is involved in rheumatoid arthritis (RA). This study explored its potential as an antirheumatic target.

EXPERIMENTAL APPROACH

WAT status of healthy and adjuvant-induced arthritis (AIA) rats were compared. The contribution of WAT to RA pathology was evaluated by pre-adipocyte transplant experiments and by dissecting perirenal fat pads of AIA rats. The impact of RA on WAT was investigated by culturing pre-adipocytes. Proteins differentially expressed in WAT of healthy and AIA rats were identified by the UPLC/MS2 method. These together with PPARγ siRNA and agonist were used to treat pre-adipocytes in vitro. The medium was used for THP-1 monocyte culture.

KEY RESULTS

Compared with healthy controls, AIA WAT was smaller but secreted more leptin, eNAMPT, MCP-1, TNF-α, and IL-6. AIA rat pre-adipocytes increased the levels of these adipokines in healthy recipients. RA patients' serum induced a similar secretion change and impaired differentiation of pre-adipocytes. Adipectomy eased AIA-related immune abnormalities and arthritic manifestations. Hepatokines PON1, IGFBP4, and GPIHBP1 were among the differential proteins in high levels in RA blood, and induced inflammatory secretions by pre-adipocytes. GPIHBP1 inhibited PPARγ expression and caused differentiation impairment and inflammatory secretion by pre-adipocytes, a similar outcome to PPARγ-silencing. This endowed the cells with an ability to activate monocytes, which can be abrogated by rosiglitazone.

CONCLUSION AND IMPLICATIONS

Certain hepatokines potentiate inflammatory secretions by pre-adipocytes and expedite RA progression by inhibiting PPARγ. Targeting this signalling or abnormal WAT secretion by various approaches may reduce RA severity.

CT-based muscle and adipose measurements predict prognosis in patients with digestive system malignancy

The role of skeletal muscle and adipose tissue in the progression of cancer has been gradually discussed, but it needs further exploration. The objective of this study was to provide an in-depth analysis of skeletal muscle and fat in digestive malignancies and to construct novel predictors for clinical management. This is a retrospective study that includes data from Cancer Center, the First Hospital of Jilin University. Basic characteristic information was analyzed by T tests. Correlation matrices were drawn to explore the relationship between CT-related indicators and other indicators. Cox risk regression analyses were performed to analyze the association between the overall survivals (OS) and various types of indicators. A new indicator body composition score (BCS) was then created and a time-dependent receiver operating characteristic curve was plotted to analyze the efficacy of the BCS. Finally, a nomogram was produced to develop a scored-CT system based on BCS and other indicators. C-index and calibration curve analyses were performed to validate the predictive accuracy of the scored-CT system. A total of 575 participants were enrolled in the study. Cox risk regression model revealed that VFD, L3 SMI and VFA/SFA were associated with prognosis of cancer patients. After adjustment, BCS index based on CT was significantly associated with prognosis, both in all study population and in subgroup analysis according to tumor types (all study population: HR 2.036, P < 0.001; colorectal cancer: HR 2.693, P < 0.001; hepatocellular carcinoma: HR 4.863, P < 0.001; esophageal cancer: HR 4.431, P = 0.008; pancreatic cancer: HR 1.905, P = 0.016; biliary system malignancies: HR 23.829, P = 0.035). The scored-CT system was constructed according to tumor type, stage, KPS, PG-SGA and BCS index, and it was of great predictive validity. This study identified VFD, L3 SMI and VFA/SFA associated with digestive malignancies outcomes. BCS was created and the scored-CT system was established to predict the OS of cancer patients.

Crosstalk between obesity and cancer: a role for adipokines

Adipose tissue is a complex organ that is increasingly being recognised as the largest endocrine organ in the body. Adipocytes among multiple cell types of adipose tissue can secrete a variety of adipokines, which are involved in signalling pathways and these can be changed by obesity and cancer. There are proposed mechanisms to link obesity/adiposity to cancer development including adipocytokine dysregulation. Among these adipokines, leptin acts through multiple pathways including the STAT3, MAPK, and PI3K pathways involved in cell growth. Adiponectin has the opposite action from leptin in tumour growth partly because of increased apoptotic responses of p53 and Bax. Visfatin increases cancer cell proliferation through ERK1/2, PI3K/AKT, and p38 which are stimulated by proinflammatory cytokines. Omentin through the PI3K/Akt-Nos pathway is involved in cancer-tumour development. Apelin might be involved through angiogenesis in tumour progressions. PAI-1 via its anti-fibrinolytic activity on cell adhesion and uPA/uPAR activity influence cancer cell growth.

The obesity-autophagy-cancer axis: Mechanistic insights and therapeutic perspectives

Autophagy, a self-degradative process vital for cellular homeostasis, plays a significant role in adipose tissue metabolism and tumorigenesis. This review aims to elucidate the complex interplay between autophagy, obesity, and cancer development, with a specific emphasis on how obesity-driven changes affect the regulation of autophagy and subsequent implications for cancer risk. The burgeoning epidemic of obesity underscores the relevance of this research, particularly given the established links between obesity, autophagy, and various cancers. Our exploration delves into hormonal influence, notably INS (insulin) and LEP (leptin), on obesity and autophagy interactions. Further, we draw attention to the latest findings on molecular factors linking obesity to cancer, including hormonal changes, altered metabolism, and secretory autophagy. We posit that targeting autophagy modulation may offer a potent therapeutic approach for obesity-associated cancer, pointing to promising advancements in nanocarrier-based targeted therapies for autophagy modulation. However, we also recognize the challenges inherent to these approaches, particularly concerning their precision, control, and the dual roles autophagy can play in cancer. Future research directions include identifying novel biomarkers, refining targeted therapies, and harmonizing these approaches with precision medicine principles, thereby contributing to a more personalized, effective treatment paradigm for obesity-mediated cancer.

Whole-Mount Imaging of Adipose Tissue Macrophages

The adipose tissue comprises highly heterogeneous macrophage populations, which play critical roles in the regulation of adipose tissue function and dysfunction during health and disease. Whole-amount staining is a powerful technique for macrophage characterization within the 3D environment of the adipose tissue, enabling the visualization of different macrophage populations and their interaction with other cells within their in vivo niche. Due to the high-fat content and softness, freezing and sectioning of adipose tissue is difficult, and distortion of tissue morphology typically occurs, especially in the case of white adipose tissue. We describe here a whole-mount staining alternative for adipose tissue imaging that preserves all structures and allows high-resolution image acquisition. We address in a step-by-step manner how to perform immunofluorescence staining of different fat pads and how to optimally visualize cellular and acellular (extracellular matrix) constituents of the adipose tissue and its vasculature, as well as resident and infiltrating macrophage populations.

Development of a novel peptide targeting GPR81 to suppress adipocyte-mediated tumor progression

GPR81, initially discovered in adipocytes, has been found to suppress lipolysis when activated. However, the current small molecules that target GPR81 carry the risk of off-target effects, and their impact on tumor progression remains uncertain. Here, we utilized phage display technology to screen a GPR81-targeting peptide named 7w-2 and proceeded to demonstrate its bioactivity. Although 7w-2 did not affect the proliferation of tumor cells, it effectively reduced adipocyte catabolism in vitro, consequently restraining the proliferation of co-cultured tumor cells. Furthermore, our findings revealed that 7w-2 could inhibit lipolysis in vivo, leading to a significant impediment in tumor growth and metastasis in the 4T1 murine tumor model. Additionally, 7w-2 exhibited the ability to significantly elevate the proportion and functionality of CD8+ T cells. Our study introduces 7w-2 as the first peptide targeting GPR81, shedding light on its potential role in adipocytes in suppressing tumor progression.

Melanoma and subcutaneous adipose tissue: Role of peritumoral adipokines in disease characterization and prognosis

In the last decades, the concept of adipose organ has emerged, giving adipose tissue an active endocrine and immunologic function through the secretion of multiple cytokines and chemokines that seem to be implicated in the development and progression of several cancer, including cutaneous melanoma. In this pilot experimental study, we analyzed the expression in the peritumor subcutaneous adipose tissue of the most significant adipokines involved in the processes of carcinogenesis and metastasis in a population of melanoma patients and in two control groups composed of melanocytic nevi and epidermoid cysts, respectively. We correlated the results obtained with the main disease prognostic factors observing a statistically significant increase in the expression of PAI1, LEP, CXCL1, NAMPT, and TNF-α at the level of the peritumor tissue of the melanoma samples compared to the control groups and a correlation of the same with the histopathological prognostic factor of melanoma. Our preliminary study shows that the overexpression of PAI1, LEP, CXCL1, NAMPT, and TNF-α may contribute to the growth and to the local aggressiveness of cutaneous melanoma. It opens the hypothesis of a direct oncogenic role of subcutaneous adipose tissue and adipokines in the tumorigenesis of melanoma.

Mitochondria: It is all about energy

Mitochondria play a key role in both health and disease. Their function is not limited to energy production but serves multiple mechanisms varying from iron and calcium homeostasis to the production of hormones and neurotransmitters, such as melatonin. They enable and influence communication at all physical levels through interaction with other organelles, the nucleus, and the outside environment. The literature suggests crosstalk mechanisms between mitochondria and circadian clocks, the gut microbiota, and the immune system. They might even be the hub supporting and integrating activity across all these domains. Hence, they might be the (missing) link in both health and disease. Mitochondrial dysfunction is related to metabolic syndrome, neuronal diseases, cancer, cardiovascular and infectious diseases, and inflammatory disorders. In this regard, diseases such as cancer, Alzheimer's, Parkinson's, amyotrophic lateral sclerosis (ALS), chronic fatigue syndrome (CFS), and chronic pain are discussed. This review focuses on understanding the mitochondrial mechanisms of action that allow for the maintenance of mitochondrial health and the pathways toward dysregulated mechanisms. Although mitochondria have allowed us to adapt to changes over the course of evolution, in turn, evolution has shaped mitochondria. Each evolution-based intervention influences mitochondria in its own way. The use of physiological stress triggers tolerance to the stressor, achieving adaptability and resistance. This review describes strategies that could recover mitochondrial functioning in multiple diseases, providing a comprehensive, root-cause-focused, integrative approach to recovering health and treating people suffering from chronic diseases.

Strategy for Pre-Clinical Development of Active Targeting MicroRNA Oligonucleotide Therapeutics for Unmet Medical Needs

We present here an innovative modular and outsourced model of drug research and development for microRNA oligonucleotide therapeutics (miRNA ONTs). This model is being implemented by a biotechnology company, namely AptamiR Therapeutics, in collaboration with Centers of Excellence in Academic Institutions. Our aim is to develop safe, effective and convenient active targeting miRNA ONT agents for the metabolic pandemic of obesity and metabolic-associated fatty liver disease (MAFLD), as well as deadly ovarian cancer.

The Extracellular Matrix: Its Composition, Function, Remodeling, and Role in Tumorigenesis

The extracellular matrix (ECM) is a ubiquitous member of the body and is key to the maintenance of tissue and organ integrity. Initially thought to be a bystander in many cellular processes, the extracellular matrix has been shown to have diverse components that regulate and activate many cellular processes and ultimately influence cell phenotype. Importantly, the ECM's composition, architecture, and stiffness/elasticity influence cellular phenotypes. Under normal conditions and during development, the synthesized ECM constantly undergoes degradation and remodeling processes via the action of matrix proteases that maintain tissue homeostasis. In many pathological conditions including fibrosis and cancer, ECM synthesis, remodeling, and degradation is dysregulated, causing its integrity to be altered. Both physical and chemical cues from the ECM are sensed via receptors including integrins and play key roles in driving cellular proliferation and differentiation and in the progression of various diseases such as cancers. Advances in 'omics' technologies have seen an increase in studies focusing on bidirectional cell-matrix interactions, and here, we highlight the emerging knowledge on the role played by the ECM during normal development and in pathological conditions. This review summarizes current ECM-targeted therapies that can modify ECM tumors to overcome drug resistance and better cancer treatment.

The Role of Oxidative Stress Enhanced by Adiposity in Cardiometabolic Diseases

Cardiometabolic diseases (CMDs), including cardiovascular disease (CVD), metabolic syndrome (MetS), and type 2 diabetes (T2D), are associated with increased morbidity and mortality. The growing prevalence of CVD is mostly attributed to the aging population and common occurrence of risk factors, such as high systolic blood pressure, elevated plasma glucose, and increased body mass index, which led to a global epidemic of obesity, MetS, and T2D. Oxidant–antioxidant balance disorders largely contribute to the pathogenesis and outcomes of CMDs, such as systemic essential hypertension, coronary artery disease, stroke, and MetS. Enhanced and disturbed generation of reactive oxygen species in excess adipose tissue during obesity may lead to increased oxidative stress. Understanding the interplay between adiposity, oxidative stress, and cardiometabolic risks can have translational impacts, leading to the identification of novel effective strategies for reducing the CMDs burden. The present review article is based on extant results from basic and clinical studies and specifically addresses the various aspects associated with oxidant–antioxidant balance disorders in the course of CMDs in subjects with excess adipose tissue accumulation. We aim at giving a comprehensive overview of existing knowledge, knowledge gaps, and future perspectives for further basic and clinical research. We provide insights into both the mechanisms and clinical implications of effects related to the interplay between adiposity and oxidative stress for treating and preventing CMDs. Future basic research and clinical trials are needed to further examine the mechanisms of adiposity-enhanced oxidative stress in CMDs and the efficacy of antioxidant therapies for reducing risk and improving outcome of patients with CMDs.

Perivascular adipose tissue: Fine-tuner of vascular redox status and inflammation

Perivascular adipose tissue (PVAT) refers to the aggregate of adipose tissue surrounding the vasculature, exhibiting the phenotypes of white, beige and brown adipocytes. PVAT has emerged as an active modulator of vascular homeostasis and pathogenesis of cardiovascular diseases in addition to its structural role to provide mechanical support to blood vessels. More specifically, PVAT is closely involved in the regulation of reactive oxygen species (ROS) homeostasis and inflammation along the vascular tree, through the tight interaction between PVAT and cellular components of the vascular wall. Furthermore, the phenotype-genotype of PVAT at different regions of vasculature varies corresponding to different cardiovascular risks. During ageing and obesity, the cellular proportions and signaling pathways of PVAT vary in favor of cardiovascular pathogenesis by promoting ROS generation and inflammation. Physiological means and drugs that alter PVAT mass, components and signaling may provide new therapeutic insights in the treatment of cardiovascular diseases. In this review, we aim to provide an updated understanding towards PVAT in the context of redox regulation, and to highlight the therapeutic potential of targeting PVAT against cardiovascular complications.

Brown adipose tissue is not associated with cachexia or increased mortality in a retrospective study of patients with cancer

Although brown fat is strongly associated with a constellation of cardiometabolic benefits in animal models and humans, it has also been tied to cancer cachexia. In humans, cancer-associated cachexia increases mortality, raising the possibility that brown fat in this context may be associated with increased cancer death. However, the effect of brown fat on cancer-associated cachexia and survival in humans remains unclear. Here, we retrospectively identify patients with and without brown fat on fluorodeoxyglucose (18F-FDG) positron-emission tomography (PET) scans obtained as part of routine cancer care and assemble a cohort to address these questions. We did not find an association between brown fat status and cachexia. Furthermore, we did not observe an association between brown fat and increased mortality in patients with cachexia. Our analyses controlled for confounding factors including age at cancer diagnosis, sex, body mass index, cancer site, cancer stage, outdoor temperature, comorbid conditions (heart failure, type 2 diabetes mellitus, coronary artery disease, hypertension, dyslipidemia, cerebrovascular disease), and β-blocker use. Taken together, our results suggest that brown fat is not linked to cancer-associated cachexia and does not worsen overall survival in patients with cachexia.NEW & NOTEWORTHY This study finds that brown fat is not linked to cancer-associated cachexia. Moreover, this work shows that brown fat does not worsen overall survival in patients with cachexia.

Dopaminergic and adrenergic receptors synergistically stimulate browning in 3T3-L1 white adipocytes

The browning of white adipose tissue (WAT) has attracted considerable attention in the scientific community as a popular strategy for enhancing energy expenditure to combat obesity. As a part of this strategy, β3-adrenergic receptor (β3-AR) is the most widely studied receptor that mediates thermogenesis. Parenthetically, further studies in search for additional receptors expressed in adipocytes that can mediate thermogenesis has been appearing, and this paper reports that dopaminergic receptor 1 (DRD1) and β3-AR synergistically stimulate browning in 3T3-L1 white adipocytes. qRT-PCR and immunoblot analysis methods were applied to evaluate the effects of DRD1 on the target proteins downstream of β3-AR and other markers involved in lipid metabolism, mitochondrial biogenesis, and browning events. These results show that DRD1 is expressed in epididymal WAT (eWAT), brown adipose tissue (BAT), and inguinal WAT (iWAT) of normal and high-fat-fed mice, and a deficiency of DRD1 downregulates the expression of brown adipocyte-specific proteins. Silencing of DRD1 affected lipid metabolic activity in 3T3-L1 adipocytes by reducing mitochondrial biogenesis as well as levels of lipolytic and fat oxidative marker proteins in a similar pattern to β3-AR. Moreover, mechanistic studies showed that the depletion of DRD1 downregulates β3-AR and its downstream molecules, suggesting both receptors might synergistically stimulate browning. Parallel to the UCP1-dependent thermogenesis, the depletion of DRD1 also downregulates the expression of core proteins responsible for UCP1-independent thermogenesis. Overall, DRD1 mediates β3-AR-dependent 3T3-L1 browning and UCP1-independent thermogenesis.

Treatment Resulting Changes in Volumes of High-18F-FDG-Uptake Adipose Tissues over Orbit and Epicardium Correlate with Treatment Response for Non-Hodgkin's Lymphoma

BACKGROUND

A regimen of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) is the standard treatment for non-Hodgkin's lymphoma. Brown adipose tissue possesses anti-cancer potential. This study aimed to explore practical biomarkers for non-Hodgkin's lymphoma by analyzing the metabolic activity of adipose tissue.

METHODS

Twenty patients who received R-CHOP for non-Hodgkin's lymphoma were reviewed. Positron emission tomography/computed tomography (PET/CT) images, lactate dehydrogenase (LDH) levels, and body mass index (BMI) before and after treatment were collected. Regions with a high standardized uptake value (SUV) in epicardial and orbital adipose tissue were selected and analyzed by a PET/CT viewer. The initial measurements and changes in the high SUV of epicardial and orbital adipose tissues, LDH levels, and BMI of treatment responders and non-responders, and complete and partial responders, were compared.

RESULTS

The volumes of high-SUV epicardial and orbital adipose tissues significantly increased in responders after R-CHOP (p = 0.03 and 0.002, respectively). There were significant differences between changes in the high-SUV volumes of epicardial and orbital adipose tissues (p = 0.03 and 0.001, respectively) and LDH levels (p = 0.03) between responders and non-responders. The changes in high-SUV epicardial adipose tissue volumes were greater among complete responders than partial responders (p = 0.04). Poorer treatment responses were observed in patients with lower high-SUV epicardial adipose tissue volumes and higher LDH levels after R-CHOP (p = 0.03 and 0.03, respectively).

CONCLUSIONS

The preliminary results of greater changes in high-SUV epicardial and orbital adipose tissue volumes among responders indicate that brown adipose tissue could be considered a favorable prognostic biomarker.

Adipose Tissue Dysfunction: Impact on Metabolic Changes?

Adipose tissue is a metabolically dynamic organ that is the primary site of storage for excess energy, but it serves as an endocrine organ capable of synthesizing a number of biologically active compounds that regulate metabolic homeostasis. However, when the capacity of expansion of this tissue exceeds, dysfunction occurs, favoring ectopic accumulation of fat in the visceral, which has been implicated in several disease states, most notably obesity. This review highlights the mechanisms involved in the structure of adipose tissue, tissue expandability, adipocyte dysfunction, as well as the impact of these events on the manifestation of important metabolic disorders associated with adipose tissue dysfunction. A literature search using Pubmed, Web of Science, Scopus, and Cochrane databases were used to identify relevant studies, using clinical trials, experimental studies in animals and humans, case-control studies, case series, letters to the editor, and review articles published in English, without restrictions on year of publication. The excessive ectopic lipid accumulation leads to local inflammation and insulin resistance. Indeed, overnutrition triggers uncontrolled inflammatory responses white adipose tissue, leading to chronic low-grade inflammation, therefore fostering the progression of important metabolic disorders. Thus, it is essential to advance the understanding of the molecular mechanisms involved in adipose tissue dysfunction in order to mitigate the negative metabolic consequences of obesity.

The Role of Intermittent Fasting in the Management of Nonalcoholic Fatty Liver Disease: A Narrative Review

Intermittent fasting is a non-pharmacological dietary approach to management of obesity and metabolic syndrome, involving periodic intervals of complete or near-complete abstinence from food and energy-containing fluids. This dietary strategy has recently gained significant popularity in mainstream culture and has been shown to induce weight loss in humans, reduce gut and systemic inflammation, and improve gut microbial diversity and dysbiosis (largely in animal models). It has been hypothesized that intermittent fasting could be beneficial in the management of nonalcoholic fatty liver disease, given the condition's association with obesity. This review summarizes protocols, potential mechanisms of action, and evidence for intermittent fasting in nonalcoholic fatty liver disease. It also highlights practical considerations for implementing intermittent fasting in clinical practice. A search of the literature for English-language articles related to intermittent fasting or time-restricted feeding and liver disease was completed in PubMed and Google Scholar. Potential mechanisms of action for effects of intermittent fasting included modulation of circadian rhythm, adipose tissue and adipokines, gut microbiome, and autophagy. Preclinical, epidemiological, and clinical trial data suggested clinical benefits of intermittent fasting on metabolic and inflammatory markers in humans. However, there was a paucity of evidence of its effects in patients with nonalcoholic fatty liver disease. More clinical studies are needed to determine mechanisms of action and to evaluate safety and efficacy of intermittent fasting in this population.

Adipokines as potential biomarkers for type 2 diabetes mellitus in cats

Type 2 diabetes mellitus (T2DM) is no longer only a disease of humans, but also of domestic animals, and it particularly affects cats. It is increasingly thought that because of its unique characteristics, T2DM may belong not only to the group of metabolic diseases but also to the group of autoimmune diseases. This is due to the involvement of the immune system in the inflammation that occurs with T2DM. Various pro- and anti-inflammatory substances are secreted, especially cytokines in patients with T2DM. Cytokines secreted by adipose tissue are called adipokines, and leptin, adiponectin, resistin, omentin, TNF-α, and IL-6 have been implicated in T2DM. In cats, approximately 90% of diabetic cases are T2DM. Risk factors include older age, male sex, Burmese breed, presence of obesity, and insulin resistance. Diagnosis of a cat requires repeated testing and is complicated compared to human diagnosis. Based on similarities in the pathogenesis of T2DM between humans and cats, adipokines previously proposed as biomarkers for human T2DM may also serve in the diagnosis of this disease in cats.

The Epigenetic Role of MiRNAs in Endocrine Crosstalk Between the Cardiovascular System and Adipose Tissue: A Bidirectional View

Overweight and obesity (OBT) is a serious health condition worldwide, and one of the major risk factors for cardiovascular disease (CVD), the main reason for morbidity and mortality worldwide. OBT is the proportional increase of Adipose Tissue (AT) compared with other tissue and fluids, associated with pathological changes in metabolism, hemodynamic overload, cytokine secretion, systemic inflammatory profile, and cardiac metabolism. In turn, AT is heterogeneous in location, and displays secretory capacity, lipolytic activation, insulin sensitivity, and metabolic status, performing anatomic, metabolic, and endocrine functions. Evidence has emerged on the bidirectional crosstalk exerted by miRNAs as regulators between the heart and AT on metabolism and health conditions. Here, we discuss the bidirectional endocrine role of miRNAs between heart and AT, rescuing extracellular vesicles’ (EVs) role in cell-to-cell communication, and the most recent results that show the potential of common therapeutic targets through the elucidation of parallel and ⁄or common epigenetic mechanisms.

Raman studies of the adipose tissue: Current state-of-art and future perspectives in diagnostics

The last decades revealed that the adipose tissue shows an unexplored therapeutic potential. In particular, targeting the perivascular adipose tissue (PVAT), that surrounds blood vessels, can prevent cardiovascular pathologies and browning of the adipose tissue can become an effective strategy against obesity. Therefore, new analytical tools are necessary to analyze this tissue. This review reports on the recent developments of various Raman-based techniques for the identification and quantification of the adipose tissue compared to conventional analytical methods. In particular, the emphasis is on analysis of PVAT, investigation of pathological changes of the adipose tissue in model systems and possibilities for its characterization in the clinical context. Overall, the review critically discusses the potential and limitations of Raman techniques in adipose tissue-targeted diagnostics and possible future anti-obesity therapies.

Differential regulation of mRNAs and lncRNAs related to lipid metabolism in Duolang and Small Tail Han sheep

The function of long non-coding RNA (lncRNA) can be achieved through the regulation of target genes, and the deposition of fat is regulated by lncRNA. Fat has an important effect on meat quality. However, there are relatively few studies on lncRNAs in the subcutaneous adipose tissue of Duolang sheep and Small Tail Han sheep. In this study, RNA-Seq technology and bioinformatics methods were used to identify and analyze the lncRNA and mRNA in the subcutaneous adipose tissue of the two breeds of sheep. The results showed that 107 lnRNAs and 1329 mRNAs were differentially expressed. The differentially expressed genes and lncRNA target genes were significantly enriched in the biosynthesis of unsaturated fatty acids signaling pathway, fatty acid metabolism, adipocyte differentiation and other processes related to fat deposition. Among them, LOC105616076, LOC114118103, LOC105607837, LOC101116622, and LOC105603235 target FADS1, SCD, ELOVL6, HSD17B12 and HACD2, respectively. They play a key regulatory role in the biosynthesis of unsaturated fatty acids. This study lays a foundation for the study of the molecular mechanism of lncRNA on fat development, and has reference value for studying the differences in fat deposition between Duolang sheep and Small Tail Han sheep.

The distinct phenotype of primary adipocytes and adipocytes derived from stem cells of white adipose tissue as assessed by Raman and fluorescence imaging

Spectroscopy-based analysis of chemical composition of cells is a tool still scarcely used in biological sciences, although it provides unique information about the cell identity accessible in vivo and in situ. Through time-lapse spectroscopic monitoring of adipogenesis in brown and white adipose tissue-derived stem cells we have demonstrated that considerable chemical and functional changes occur along with cells differentiation and maturation, yet yielding mature adipocytes with a similar chemical composition, independent of the cellular origin (white or brown adipose tissue). However, in essence, these stem cell-derived adipocytes have a markedly different chemical composition compared to mature primary adipocytes. The consequences of this different chemical (and, hence, functional) identity have great importance in the context of selecting a suitable methodology for adipogenesis studies, particularly in obesity-related research.

Evaluation of brown adipose tissue with intermolecular double-quantum coherence magnetic resonance spectroscopy at 3.0 T

In the current study, we propose a single-voxel (SV) magnetic resonance spectroscopy (MRS) pulse sequence, based on intermolecular double-quantum coherence (iDQC), for in vivo specific assessment of brown adipose tissue (BAT) at 3 T. The multilocular adipocyte, present in BAT, typically contains a large number of small lipid droplets surrounded by abundant intracellular water, while the monolocular adipocyte, present in white adipose tissue (WAT), accommodates only a single large lipid droplet with much less water content. The SV-iDQC sequence probes the spatial correlation between water and fat spins at a distance of about the size of an adipocyte, thus can be used for assessment of BAT, even when mixed with WAT and/or muscle tissues. This sequence for measurement of water-to-fat (water-fat) iDQC signals was tested on phantoms and mouse BAT and WAT tissues. It was then used to differentiate adipose tissues in the supraclavicular and subcutaneous regions of healthy youth human volunteers (n = 6). Phantom results with water-fat emulsions demonstrated enhanced water-fat iDQC signal with increased voxel size, increased energy level of emulsification, or increased distribution balance of water and fat spins. The animal tissue experiments resulted in obvious water-fat iDQC signal in mouse BAT, while this signal was almost absent in the WAT spectrum. The optimal choice of the dipolar coupling distance for the observation was approximately 100 μm, as tested on both emulsion phantom and animal tissue. The water-fat iDQC signals observed in the supraclavicular adipose tissues were higher than in the subcutaneous adipose tissues in healthy young volunteers (0.43 ± 0.36 vs. 0.10 ± 0.06, p = 0.06). It was concluded that the iDQC-based sequence has potential for assessment of mouse and human BAT at 3 T, which is of interest for clinical research and the diagnosis of obesity and associated diseases.

Autologous Human Immunocompetent White Adipose Tissue-on-Chip

Obesity and associated diseases, such as diabetes, have reached epidemic proportions globally. In this era of "diabesity", white adipose tissue (WAT) has become a target of high interest for therapeutic strategies. To gain insights into mechanisms of adipose (patho-)physiology, researchers traditionally relied on animal models. Leveraging Organ-on-Chip technology, a microphysiological in vitro model of human WAT is introduced: a tailored microfluidic platform featuring vasculature-like perfusion that integrates 3D tissues comprising all major WAT-associated cellular components (mature adipocytes, organotypic endothelial barriers, stromovascular cells including adipose tissue macrophages) in an autologous manner and recapitulates pivotal WAT functions, such as energy storage and mobilization as well as endocrine and immunomodulatory activities. A precisely controllable bottom-up approach enables the generation of a multitude of replicates per donor circumventing inter-donor variability issues and paving the way for personalized medicine. Moreover, it allows to adjust the model's degree of complexity via a flexible mix-and-match approach. This WAT-on-Chip system constitutes the first human-based, autologous, and immunocompetent in vitro adipose tissue model that recapitulates almost full tissue heterogeneity and can become a powerful tool for human-relevant research in the field of metabolism and its associated diseases as well as for compound testing and personalized- and precision medicine applications.

The Immune Response in Adipocytes and Their Susceptibility to Infection: A Possible Relationship with Infectobesity

The current obesity pandemic has been expanding in both developing and developed countries. This suggests that the factors contributing to this condition need to be reconsidered since some new factors are arising as etiological causes of this disease. Moreover, recent clinical and experimental findings have shown an association between the progress of obesity and some infections, and the functions of adipose tissues, which involve cell metabolism and adipokine release, among others. Furthermore, it has recently been reported that adipocytes could either be reservoirs for these pathogens or play an active role in this process. In addition, there is abundant evidence indicating that during obesity, the immune system is exacerbated, suggesting an increased susceptibility of the patient to the development of several forms of illness or death. Thus, there could be a relationship between infection as a trigger for an increase in adipose cells and the impact on the metabolism that contributes to the development of obesity. In this review, we describe the findings concerning the role of adipose tissue as a mediator in the immune response as well as the possible role of adipocytes as infection targets, with both roles constituting a possible cause of obesity.

Adipose Tissue Extracellular Matrix Remodeling in Response to Dietary Patterns and Exercise: Molecular Landscape, Mechanistic Insights, and Therapeutic Approaches

Simple Summary

Adipose tissue is considered a metabolic organ that adjusts overall energy homeostasis and critical hormones to the body’s needs. In conditions of caloric intake surpassing energy expenditure, lipid accumulation occurs with constant extracellular matrix deposition. Excess lipids and adipocyte hypertrophy may reduce extracellular matrix flexibility in conjunction with hypoxia and inflammation. These processes induce the development of adipose tissue fibrosis and correlated metabolic dysfunctions, such as insulin resistance. With the increasing rate of chronic diseases worldwide, it is essential to generate a more precise knowledge of fibrotic processes, as well as to create optimal models to study potential therapies to combat the harmful effects of extracellular matrix deposition. In this work, we focused on the physiological processes in the remodeling of adipose tissue fibrosis, along with their relevance to clinical indications. Furthermore, we emphasize understanding how lifestyle can alleviate adipocyte dysfunction. Several studies showed that a nutritionally balanced diet combined with exercise is a remarkable potential strategy for lipolytic activity, preventing rapid extracellular matrix expansion in parallel with insulin and glucose action improvements. Thus, the emerging beneficial role of exercise training and low-calorie diet on adipose tissue ECM remodeling is a topic that deserves attention from health professionals.

Abstract

The extracellular matrix (ECM) is a 3-dimensional network of molecules that play a central role in differentiation, migration, and survival for maintaining normal homeostasis. It seems that ECM remodeling is required for adipose tissue expansion. Despite evidence indicating that ECM is an essential component of tissue physiology, adipose tissue ECM has received limited attention. Hence, there is great interest in approaches to neutralize the harmful effects of ECM enlargement. This review compiles and discusses the current literature on adipose tissue ECM remodeling in response to different dietary patterns and exercise training. High-calorie diets result in substantial adipose tissue ECM remodeling, which in turn could lead to fibrosis (excess deposition of collagens, elastin, and fibronectin), inflammation, and the onset of metabolic dysfunction. However, combining a nutritionally balanced diet with exercise is a remarkable potential strategy for lipolytic activity, preventing rapid ECM expansion in different adipose tissue depots. Despite the distinct exercise modalities (aerobic or resistance exercise) reversing adipose tissue fibrosis in animal models, the beneficial effect on humans remains controversial. Defining molecular pathways and specific mechanisms that mediate the positive effects on adipose tissue, ECM is essential in developing optimized interventions to improve health and clinical outcomes.

Targeting of the Peritumoral Adipose Tissue Microenvironment as an Innovative Antitumor Therapeutic Strategy

The tumor microenvironment (TME) plays a key role in promoting and sustaining cancer growth. Adipose tissue (AT), due to its anatomical distribution, is a prevalent component of TME, and contributes to cancer development and progression. Cancer-associated adipocytes (CAAs), reprogrammed by cancer stem cells (CSCs), drive cancer progression by releasing metabolites and inflammatory adipokines. In this review, we highlight the mechanisms underlying the bidirectional crosstalk among CAAs, CSCs, and stromal cells. Moreover, we focus on the recent advances in the therapeutic targeting of adipocyte-released factors as an innovative strategy to counteract cancer progression.

Transdermal Delivery of Metformin Using Dissolving Microneedles and Iontophoresis Patches for Browning Subcutaneous Adipose Tissue

Obesity is a serious public health problem that is strongly associated with increased multiple comorbidities such as diabetes, cardiovascular disease, and some types of cancer. While current anti-obesity treatments have various issues, locally transforming energy-storing white adipose tissue (WAT) into energy-burning brown-like/beige adipose tissue, the so-called browning of WAT, has been suggested to enhance obesity treatment efficiency with minimized side effects. Metformin is a first-line antidiabetes drug and a potent activator of AMP-activated protein kinase. Emerging evidence has suggested that metformin might enhance energy expenditure via the browning of WAT and hence reduce body weight. Subcutaneous WAT is easier to access and has a stronger browning potential than other WAT depots. In this study, we used dissolvable poly (lactic-co-glycolic acid) microneedles (MN) to deliver metformin to the subcutaneous WAT in obese C57BL/6J mice with the assistance of iontophoresis (INT), and then investigated metformin-induced WAT browning and its subsequent thermogenesis effects. Compared with MN alone or INT alone, MN + INT had better anti-obesity activity, as indicated by decreasing body weight and fat gain, increased energy expenditure, decreased fat pad size, and improved energy metabolism through the browning of WAT. Browning subcutaneous WAT by delivering metformin and other browning agents using this MN + INT approach might combat obesity in an effective, easy, and safe regimen.

Thromboinflammatory Processes at the Nexus of Metabolic Dysfunction and Prostate Cancer: The Emerging Role of Periprostatic Adipose Tissue

Simple Summary

As overweight and obesity increase among the population worldwide, a parallel increase in the number of individuals diagnosed with prostate cancer was observed. There appears to be a relationship between both diseases where the increase in the mass of fat tissue can lead to inflammation. Such a state of inflammation could produce many factors that increase the aggressiveness of prostate cancer, especially if this inflammation occurred in the fat stores adjacent to the prostate. Another important observation that links obesity, fat tissue inflammation, and prostate cancer is the increased production of blood clotting factors. In this article, we attempt to explain the role of these latter factors in the effect of increased body weight on the progression of prostate cancer and propose new ways of treatment that act by affecting how these clotting factors work.

Abstract

The increased global prevalence of metabolic disorders including obesity, insulin resistance, metabolic syndrome and diabetes is mirrored by an increased incidence of prostate cancer (PCa). Ample evidence suggests that these metabolic disorders, being characterized by adipose tissue (AT) expansion and inflammation, not only present as risk factors for the development of PCa, but also drive its increased aggressiveness, enhanced progression, and metastasis. Despite the emerging molecular mechanisms linking AT dysfunction to the various hallmarks of PCa, thromboinflammatory processes implicated in the crosstalk between these diseases have not been thoroughly investigated. This is of particular importance as both diseases present states of hypercoagulability. Accumulating evidence implicates tissue factor, thrombin, and active factor X as well as other players of the coagulation cascade in the pathophysiological processes driving cancer development and progression. In this regard, it becomes pivotal to elucidate the thromboinflammatory processes occurring in the periprostatic adipose tissue (PPAT), a fundamental microenvironmental niche of the prostate. Here, we highlight key findings linking thromboinflammation and the pleiotropic effects of coagulation factors and their inhibitors in metabolic diseases, PCa, and their crosstalk. We also propose several novel therapeutic targets and therapeutic interventions possibly modulating the interaction between these pathological states.

Early life exposure to nicotine modifies lung gene response after elastase-induced emphysema

Background

Chronic obstructive pulmonary disease (COPD) is among the top 5 causes of mortality in the world and can develop as a consequence of genetic and/or environmental factors. Current efforts are focused on identifying early life insults and how these contribute to COPD development. In line with this, our study focuses on the influence of early life nicotine exposure and its potential impact on (a) lung pulmonary functions, and (b) elastase-induced emphysema in adulthood.

Methods

To address this hypothesis, we developed a model of 2 hits, delivered at different time points: mouse pups were first exposed to nicotine/placebo in utero and during lactation, and then subsequently received elastase/placebo at the age of 11 weeks. The effect of nicotine pretreatment and elastase instillation was assessed by (a) measurement of pulmonary function at post-elastase day (ped) 21, and (b) transcriptomic profiling at ped3 and 21, and complementary protein determination. Statistical significance was determined by 3- and 2-way ANOVA for pulmonary functions, and RNAseq results were analyzed using the R project.

Results

We did not observe any impact of nicotine pre- and early post-natal exposure compared to control samples on lung pulmonary functions in adulthood, as measured by FLEXIVENT technology. After elastase instillation, substantial lung damage was detected by x-ray tomography and was accompanied by loss in body weight at ped3 as well as an increase in cell numbers, inflammatory markers in BAL and lung volume at ped21. Lung functions showed a decrease in elastance and an increase in deep inflation volume and pressure volume (pv) loop area in animals with emphysema at ped21. Nicotine had no effect on elastance and deep inflation volume, but did affect the pv loop area in animals with emphysema at ped21. Extensive transcriptomic changes were induced by elastase at ped3 both in the nicotine-pretreated and the control samples, with several pathways common to both groups, such as for cell cycle, DNA adhesion and DNA damage. Nicotine pretreatment affected the number of lymphocytes present in BAL after elastase instillation and some of the complement pathway related proteins, arguing for a slight modification of the immune response, as well as changes related to general body metabolism. The majority of elastase-induced transcriptomic changes detected at ped3 had disappeared at ped21. In addition, transcriptomic profiling singled out a common gene pool that was independently activated by nicotine and elastase.

Conclusions

Our study reports a broad spectrum of transient transcriptomic changes in mouse emphysema and identifies nicotine as influencing the emphysema-associated immune system response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01956-4.

The ambiguous role of obesity in oncology by promoting cancer but boosting antitumor immunotherapy

Obesity is nowadays considered a pandemic which prevalence's has been steadily increasingly in western countries. It is a dynamic, complex, and multifactorial disease which propitiates the development of several metabolic and cardiovascular diseases, as well as cancer. Excessive adipose tissue has been causally related to cancer progression and is a preventable risk factor for overall and cancer-specific survival, associated with poor prognosis in cancer patients. The onset of obesity features a state of chronic low-grade inflammation and secretion of a diversity of adipocyte-derived molecules (adipokines, cytokines, hormones), responsible for altering the metabolic, inflammatory, and immune landscape. The crosstalk between adipocytes and tumor cells fuels the tumor microenvironment with pro-inflammatory factors, promoting tissue injury, mutagenesis, invasion, and metastasis. Although classically established as a risk factor for cancer and treatment toxicity, recent evidence suggests mild obesity is related to better outcomes, with obese cancer patients showing better responses to treatment when compared to lean cancer patients. This phenomenon is termed obesity paradox and has been reported in different types and stages of cancer. The mechanisms underlying this paradoxical relationship between obesity and cancer are still not fully described but point to systemic alterations in metabolic fitness and modulation of the tumor microenvironment by obesity-associated molecules. Obesity impacts the response to cancer treatments, such as chemotherapy and immunotherapy, and has been reported as having a positive association with immune checkpoint therapy. In this review, we discuss obesity's association to inflammation and cancer, also highlighting potential physiological and biological mechanisms underlying this association, hoping to clarify the existence and impact of obesity paradox in cancer development and treatment.

Exercise and/or Cold Exposure Alters the Gene Expression Profile in the Fat Body and Changes the Heart Function in Drosophila

The major reason of human morbidity and mortality is obesity and related diseases. Brown adipose tissue (BAT) is associated with low total adipose tissue content and a lower risk of type 2 diabetes mellitus. Studies have shown that exercise and cold expose may induce browning. In this study, we verified (1) whether exercise and/or cold exposure can improve the expression level of ucp4c, serca, ampkα, camkII, sirt1, octβ3r, and hamlet; (2) if these interventions can save cardiac dysfunction induced by a high-fat diet (HFD) in Drosophila. w1118 (wild-type) virgin female flies collected within 8 h after eclosion were divided into eight groups: the normal feed control group (NFD-C), the normal feed exercise group (NFD-E), the normal feed cold exposure group (NFD-CA), the normal feed exercise/cold exposure group (NFD-EC), the HFD control group (HFD-C), the HFD exercise group (HFD-E), the HFD cold exposure group (HFD-CA), and the HFD exercise/cold exposure group (HFD-EC). After exercise and/or cold exposure for 7 days, the mRNA expression levels of ucp4c, serca, ampkα, camk II, sirt1, octβ3r, and hamlet were tested by qRT-PCR, and m-mode was used to assess cardiac function. In addition, we assessed the triacylglycerol (TAG) levels, motor ability, fat mass (by Oil Red O [ORO] staining), and morphological features. The results of TAG, ORO staining, and morphological features all indicate that after interventions, body size of Drosophila was smaller compared with the control group, irrespective of the feeding patterns. The mRNA expression levels of ucp4c, serca, octβ3r, hamlet, ampkα, camkII, and sirt1 were changed to varying degrees under different intervention states (exercise and/or cold exposure). Cold exposure and exercise/cold exposure partly improved cardiac function and the normal fruit flies' cardiac function and exercise ability. However, after exercise intervention, exercise ability and heart function were improved in both HFD and normal-fat diet (NFD) fruit flies. In conclusion, different intervention states (exercise and/or cold exposure) can change the mRNA expression levels of ucp4c, serca, octβ3r, hamlet, ampkα, camkII, and sirt1. Exercise is the most effective way to restore HFD-induced cardiac dysfunction.

Short histological kaleidoscope - recent findings in histology. Part I

This article is a review of new advances in histology, concerning either classification or structure of different tissular elements (basement membrane, hemidesmosomes, urothelium, glandular epithelia, adipose tissue, astrocytes), and various organs' constituents (blood-brain barrier, human dental cementum, tubarial salivary glands, hepatic stellate cells, pineal gland, fibroblasts of renal interstitium, Leydig testicular cells, ovarian hilar cells), as well as novel biotechnological techniques (tissue engineering in angiogenesis), recently introduced.

Obesity and adipose tissue impact on T-cell response and cancer immune checkpoint blockade therapy

Many different types of cancer are now well known to have increased occurrence or severity in individuals with obesity. The influence of obesity on cancer and the immune cells in the tumor microenvironment has been thought to be a pleiotropic effect. As key endocrine and immune organs, the highly plastic adipose tissues play crucial roles in obesity pathophysiology, as they show alterations according to environmental cues. Adipose tissues of lean subjects present mostly anti-inflammatory cells that are crucial in tissue remodeling, favoring uncoupling protein 1 expression and non-shivering thermogenesis. Oppositely, obese adipose tissues display massive proinflammatory immune cell infiltration, dying adipocytes, and enhanced crown-like structure formation. In this review, we discuss how obesity can lead to derangements and dysfunctions in antitumor CD8+ T lymphocytes dysfunction. Moreover, we explain how obesity can affect the efficiency of cancer immunotherapy, depicting the mechanisms involved in this process. Cancer immunotherapy management includes monoclonal antibodies targeting the immune checkpoint blockade. Exhausted CD8+ T lymphocytes show elevated programmed cell death-1 (PD-1) expression and highly glycolytic tumors tend to show a good response to anti-PD-1/PD-L1 immunotherapy. Although obesity is a risk factor for the development of several neoplasms and is linked with increased tumor growth and aggressiveness, obesity is also related to improved response to cancer immunotherapy, a phenomenon called the obesity paradox. However, patients affected by obesity present higher incidences of adverse events related to this therapy. These limitations highlight the necessity of a deeper investigation of factors that influence the obesity paradox to improve the application of these therapies.

Alcohol and Metabolic-associated Fatty Liver Disease

The diagnosis of metabolic-associated fatty liver disease is based on the detection of liver steatosis together with the presence of metabolic dysfunction. According to this new definition, the diagnosis of metabolic-associated fatty liver disease is independent of the amount of alcohol consumed. Actually, alcohol and its metabolites have various effects on metabolic-associated abnormalities during the process of alcohol metabolism. Studies have shown improved metabolic function in light to moderate alcohol drinkers. There are several studies focusing on the role of light to moderate alcohol intake on metabolic dysfunction. However, the results from studies are diverse, and the conclusions are often controversial. This review systematically discusses the effects of alcohol consumption, focusing on light to moderate alcohol consumption, obesity, lipid and glucose metabolism, and blood pressure.

Impact of Vitamin D Supplementation on Inflammatory Markers' Levels in Obese Patients

In view of research suggesting a possible beneficial impact of vitamin D on systemic inflammatory response, the authors decided to investigate an influence of vitamin D supplementation on serum levels of certain inflammatory markers in obese patients. The current study included such biomarkers as interleukin-6 (IL-6), pituitary adenylate cyclase-activating peptide (PACAP), advanced oxidation protein products (AOPP), C-X3-C Motif Chemokine Ligand 1 (CX3CL1), monocyte chemoattractant protein-1 (MCP-1), and nitric oxide (NO). The measurements were performed with the ELISA method before and after 3-month-long supplementation of 2000 IU of vitamin D orally. The results showed that the therapy did not induce any statistically significant changes in serum levels of MCP-1, IL-6, CX3CL1, and PACAP. The supplementation was related to a significant increase in measurements of NO and AOPP levels, although the correlation analysis between vitamin D concentration after its supplementation and the concentration of the molecular parameters did not show significant relation. In conclusion, our study seems to contradict certain aspects of findings available in the literature regarding the vitamin D’s impact.

Nordic Walking at Maximal Fat Oxidation Intensity Decreases Circulating Asprosin and Visceral Obesity in Women With Metabolic Disorders

OBJECTIVE

Excess visceral adipose tissue is associated with insulin resistance and other metabolic disorders, including deregulation of adipokine secretion, which may be corrected by aerobic exercise training. Asprosin is a novel adipokine responsible for the regulation of appetite and the release of glucose from the liver, and its levels are pathologically elevated in obesity. The aim of the study was to evaluate the effects of 8-week Nordic walking (NW) training at maximal fat oxidation intensity (FAT max ) on changes in body mass, as well as those in insulin resistance and asprosin levels among young women with visceral obesity and metabolic disorders.

MATERIALS AND METHODS

The study was completed by 14 women (30.14 ± 3.63 years) representing low levels of physical activity, visceral obesity (waist circumference 105.50 ± 14.87 cm, BMI 33.85 ± 5.48 kg/m2) and with metabolic disorders, who for 8 weeks (three times a week, 60 min), participated in NW training at the FAT max intensity (61.92 ± 6.71% HR max , 42.33 ± 8.69% VO2max) controlled on the basis of heart rate (114.21 ± 14.10 bpm).

RESULTS

After 4 and 8 weeks of NW training, a significant decrease in the concentration of asprosin, waist and hip circumference (HC), waist-to-height ratio and body adiposity index (BAI) (p < 0.05, large effect size) were found.

CONCLUSION

The 8-week NW training at an FAT max intensity decreases the concentration of asprosin in the blood as well as visceral obesity in young women with metabolic disorders.

Inflammation and tumor progression: signaling pathways and targeted intervention

Cancer development and its response to therapy are regulated by inflammation, which either promotes or suppresses tumor progression, potentially displaying opposing effects on therapeutic outcomes. Chronic inflammation facilitates tumor progression and treatment resistance, whereas induction of acute inflammatory reactions often stimulates the maturation of dendritic cells (DCs) and antigen presentation, leading to anti-tumor immune responses. In addition, multiple signaling pathways, such as nuclear factor kappa B (NF-kB), Janus kinase/signal transducers and activators of transcription (JAK-STAT), toll-like receptor (TLR) pathways, cGAS/STING, and mitogen-activated protein kinase (MAPK); inflammatory factors, including cytokines (e.g., interleukin (IL), interferon (IFN), and tumor necrosis factor (TNF)-α), chemokines (e.g., C-C motif chemokine ligands (CCLs) and C-X-C motif chemokine ligands (CXCLs)), growth factors (e.g., vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β), and inflammasome; as well as inflammatory metabolites including prostaglandins, leukotrienes, thromboxane, and specialized proresolving mediators (SPM), have been identified as pivotal regulators of the initiation and resolution of inflammation. Nowadays, local irradiation, recombinant cytokines, neutralizing antibodies, small-molecule inhibitors, DC vaccines, oncolytic viruses, TLR agonists, and SPM have been developed to specifically modulate inflammation in cancer therapy, with some of these factors already undergoing clinical trials. Herein, we discuss the initiation and resolution of inflammation, the crosstalk between tumor development and inflammatory processes. We also highlight potential targets for harnessing inflammation in the treatment of cancer.

Dermal white adipose tissue: Much more than a metabolic, lipid-storage organ?

The role of dermal white adipose tissue (dWAT) has emerged in the biomedical science as an ancillary fat district in the derma without a defined and distinct function respect to the subcutaneous adipose tissue (sWAT). Despite some evidence describing dWAT as an immune-competent compartment, particularly engaged in wound repair, very few reports dealing with dWAT has elucidated its major modulatory role within the skin biology. Whereas an increasing bulk of evidence allows researcher to describe the main activity of sWAT, in humans dWAT is not properly a separated fat compartment and therefore scarcely considered in the scientific debate. Due to its strategic position between epidermis and sWAT, dermal fat might play a much more intriguing role than expected. This review tries to shed light on this issue, by expanding the debate about a possible role of dWAT in skin physiology.

Mammary gland adipocytes in lactation cycle, obesity and breast cancer

The mammary gland (MG) is an exocrine gland present in female mammals responsible for the production and secretion of milk during the process of lactation. It is mainly composed by epithelial cells and adipocytes. Among the features that make the MG unique there are 1) its highly plastic properties displayed during pregnancy, lactation and involution (all steps belonging to the lactation cycle) and 2) its requirement to grow in close association with adipocytes which are absolutely necessary to ensure MG's proper development at puberty and remodeling during the lactation cycle. Although MG adipocytes play such a critical role for the gland development, most of the studies have focused on its epithelial component only, leaving the role of the neighboring adipocytes largely unexplored. In this review we aim to describe evidences regarding MG's adipocytes role and properties in physiologic conditions (gland development and lactation cycle), obesity and breast cancer, emphasizing the existing gaps in the literature which deserve further investigation.

Lnc13728 facilitates human mesenchymal stem cell adipogenic differentiation via positive regulation of ZBED3 and downregulation of the WNT/β-catenin pathway

Background

Obesity has received increasing attention because of its widespread worldwide occurrence and many threats to health. Human adipose-derived mesenchymal stem cells (hADSCs) are a critical source of adipocytes. Long noncoding RNAs (lncRNAs) play pivotal roles in cell fate determination and differentiation. The objective of the present study was to identify and investigate the function and regulatory mechanism of lncRNAs on adipogenic differentiation of hADSCs.

Methods

We used lncRNA arrays to identify the prominent differentially expressed lncRNAs before and after hADSC adipogenic differentiation and verified their biological function through antisense oligonucleotide knockdown or lentivirus overexpression. The adipogenic differentiation of hADSCs was assessed by oil red O staining as well as the mRNA and protein levels of adipogenic marker genes through qRT-PCR and western blot. Bioinformatic tool LncPro and immunofluorescence was performed to uncover the interaction between lnc13728 and ZBED3. WNT/β-catenin signaling pathway was evaluated by western blot and immunofluorescence.

Results

The lncRNA arrays showed that lnc13728 expression was significantly upregulated after hADSC adipogenic differentiation and was correlated positively with the expression of the adipogenesis-related genes in human adipose tissue. Lnc13728 knockdown in hADSCs suppressed the expression of the adipogenesis-related genes at both mRNA and protein level and weakened lipid droplet production. Accordingly, lnc13728 overexpression enhanced hADSC adipogenic differentiation. Beyond that, lnc13728 co-localized with ZBED3 in the cytoplasm and regulated its expression positively. Downregulating ZBED3 had a negative effect on adipogenic differentiation, while the expression of WNT/β-catenin signaling pathway-related proteins was upregulated.

Conclusions

Lnc13728 promotes hADSC adipogenic differentiation possibly by positively regulating the expression of ZBED3 which plays a role in inhibiting the WNT/β-catenin pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02250-8.

Beneficial effects of brown fat activation on top of PCSK9 inhibition with alirocumab on dyslipidemia and atherosclerosis development in APOE*3-Leiden.CETP mice

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition, by increasing hepatic low density lipoprotein (LDL) receptor (LDLR) levels, has emerged as a strategy to reduce atherosclerosis by lowering circulating very low density lipoprotein (VLDL)-cholesterol. We hypothesized that the therapeutic effectiveness of PCSK9 inhibition can be increased by accelerating the generation of VLDL remnants, which typically have a high affinity for the LDLR. Therefore, we aimed to investigate whether accelerating lipolytic processing of VLDL by brown fat activation can further lower (V)LDL and reduce atherosclerosis on top of PCSK9 inhibition. APOE*3-Leiden.CETP mice were fed a Western-type diet and treated with the anti-PCSK9 antibody alirocumab or saline. After 2 weeks, both groups of mice were randomized to receive either the selective β3-adrenergic receptor (AR) agonist CL316,243 to activate brown fat or saline for 3 additional weeks to evaluate VLDL clearance or 12 additional weeks to analyze atherosclerosis development. β3-AR agonism and alirocumab combined decreased (V)LDL-cholesterol compared to alirocumab alone, which was explained by an accelerated plasma clearance of VLDL-cholesteryl esters that were mainly taken up by the liver. In addition, the combination promoted the transfer of VLDL-phospholipids to HDL to a higher extent than alirocumab alone, accompanied by higher plasma HDL-cholesterol levels and increased cholesterol efflux capacity. Consequently, combination treatment largely reduced atherosclerotic lesion area compared to vehicle. Together, β3-AR agonism enhances the lipoprotein-modulating effects of alirocumab to further improve dyslipidemia and non-significantly further attenuate atherosclerosis development. Our findings demonstrate that brown fat activation may enhance the therapeutic effects of PCSK9 inhibition in dyslipidemia.

Inflammation-Related Carcinogenesis: Lessons from Animal Models to Clinical Aspects

Simple Summary

In multicellular organisms, inflammation is the body’s most primitive and essential protective response against any external agent. Inflammation, however, not only causes various modern diseases such as cardiovascular disorders, neurological disorders, autoimmune diseases, metabolic syndrome, infectious diseases, and cancer but also shortens the healthy life expectancy. This review focuses on the onset of carcinogenesis due to chronic inflammation caused by pathogen infections and inhalation/ingestion of foreign substances. This study summarizes animal models associated with inflammation-related carcinogenesis by organ. By determining factors common to inflammatory carcinogenesis models, we examined strategies for the prevention and treatment of inflammatory carcinogenesis in humans.

Abstract

Inflammation-related carcinogenesis has long been known as one of the carcinogenesis patterns in humans. Common carcinogenic factors are inflammation caused by infection with pathogens or the uptake of foreign substances from the environment into the body. Inflammation-related carcinogenesis as a cause for cancer-related death worldwide accounts for approximately 20%, and the incidence varies widely by continent, country, and even region of the country and can be affected by economic status or development. Many novel approaches are currently available concerning the development of animal models to elucidate inflammation-related carcinogenesis. By learning from the oldest to the latest animal models for each organ, we sought to uncover the essential common causes of inflammation-related carcinogenesis. This review confirmed that a common etiology of organ-specific animal models that mimic human inflammation-related carcinogenesis is prolonged exudation of inflammatory cells. Genotoxicity or epigenetic modifications by inflammatory cells resulted in gene mutations or altered gene expression, respectively. Inflammatory cytokines/growth factors released from inflammatory cells promote cell proliferation and repair tissue injury, and inflammation serves as a “carcinogenic niche”, because these fundamental biological events are common to all types of carcinogenesis, not just inflammation-related carcinogenesis. Since clinical strategies are needed to prevent carcinogenesis, we propose the therapeutic apheresis of inflammatory cells as a means of eliminating fundamental cause of inflammation-related carcinogenesis.

Endurance Exercise Mitigates Immunometabolic Adipose Tissue Disturbances in Cancer and Obesity

Adipose tissue is considered an endocrine organ whose complex biology can be explained by the diversity of cell types that compose this tissue. The immune cells found in the stromal portion of adipose tissue play an important role on the modulation of inflammation by adipocytokines secretion. The interactions between metabolic active tissues and immune cells, called immunometabolism, is an important field for discovering new pathways and approaches to treat immunometabolic diseases, such as obesity and cancer. Moreover, physical exercise is widely known as a tool for prevention and adjuvant treatment on metabolic diseases. More specifically, aerobic exercise training is able to increase the energy expenditure, reduce the nutrition overload and modify the profile of adipocytokines and myokines with paracrine and endocrine effects. Therefore, our aim in this review was to cover the effects of aerobic exercise training on the immunometabolism of adipose tissue in obesity and cancer, focusing on the exercise-related modification on adipose tissue or immune cells isolated as well as their interaction.

Adipogenesis in Different Body Depots and Tumor Development

Adipose tissue (AT) forms depots at different anatomical locations throughout the body, being in subcutaneous and visceral regions, as well as the bone marrow. These ATs differ in the adipocyte functional profile, their insulin sensitivity, adipokines’ production, lipolysis, and response to pathologic conditions. Despite the recent advances in lineage tracing, which have demonstrated that individual adipose depots are composed of adipocytes derived from distinct progenitor populations, the cellular and molecular dissection of the adipose clonogenic stem cell niche is still a great challenge. Additional complexity in AT regulation is associated with tumor-induced changes that affect adipocyte phenotype. As an integrative unit of cell differentiation, AT microenvironment regulates various phenotype outcomes of differentiating adipogenic lineages, which consequently may contribute to the neoplastic phenotype manifestations. Particularly interesting is the capacity of AT to impose and support the aberrant potency of stem cells that accompanies tumor development. In this review, we summarize the current findings on the communication between adipocytes and their progenitors with tumor cells, pointing out to the co-existence of healthy and neoplastic stem cell niches developed during tumor evolution. We also discuss tumor-induced adaptations in mature adipocytes and the involvement of alternative differentiation programs.

The Impact of Adipose Tissue-Derived miRNAs in Metabolic Syndrome, Obesity, and Cancer

Obesity is a multifactorial and complex condition that is characterized by abnormal and excessive white adipose tissue accumulation, which can lead to the development of metabolic diseases, such as type 2 diabetes mellitus, nonalcoholic fatty liver disease, cardiovascular diseases, and several types of cancer. Obesity is characterized by excessive adipose tissue accumulation and associated with alterations in immunity, displaying a chronic low-grade inflammation profile. Adipose tissue is a dynamic and complex endocrine organ composed not only by adipocytes, but several immunological cells, which can secrete hormones, cytokines and many other factors capable of regulating metabolic homeostasis and several critical biological pathways. Remarkably, adipose tissue is a major source of circulating microRNAs (miRNAs), recently described as a novel form of adipokines. Several adipose tissue-derived miRNAs are deeply associated with adipocytes differentiation and have been identified with an essential role in obesity-associated inflammation, insulin resistance, and tumor microenvironment. During obesity, adipose tissue can completely change the profile of the secreted miRNAs, influencing circulating miRNAs and impacting the development of different pathological conditions, such as obesity, metabolic syndrome, and cancer. In this review, we discuss how miRNAs can act as epigenetic regulators affecting adipogenesis, adipocyte differentiation, lipid metabolism, browning of the white adipose tissue, glucose homeostasis, and insulin resistance, impacting deeply obesity and metabolic diseases. Moreover, we characterize how miRNAs can often act as oncogenic and tumor suppressor molecules, significantly modulating cancer establishment and progression. Furthermore, we highlight in this manuscript how adipose tissue-derived miRNAs can function as important new therapeutic targets.

The Role of Dysfunctional Adipose Tissue in Pancreatic Cancer: A Molecular Perspective

Pancreatic cancer (PC) is a lethal malignancy with rising incidence and limited therapeutic options. Obesity is a well-established risk factor for PC development. Moreover, it negatively affects outcome in PC patients. Excessive fat accumulation in obese, over- and normal-weight individuals induces metabolic and inflammatory changes of adipose tissue microenvironment leading to a dysfunctional adipose “organ”. This may drive the association between abnormal fat accumulation and pancreatic cancer. In this review, we describe several molecular mechanisms that underpin this association at both local and systemic levels. We focus on the role of adipose tissue-derived circulating factors including adipokines, hormones and pro-inflammatory cytokines, as well as on the impact of the local adipose tissue in promoting PC. A discussion on potential therapeutic interventions, interfering with pro-tumorigenic effects of dysfunctional adipose tissue in PC, is included. Considering the raise of global obesity, research efforts to uncover the molecular basis of the relationship between pancreatic cancer and adipose tissue dysfunction may provide novel insights for the prevention of this deadly disease. In addition, these efforts may uncover novel targets for personalized interventional strategies aimed at improving the currently unsatisfactory PC therapeutic options.

Aspirin Modifies Inflammatory Mediators and Metabolomic Profiles and Contributes to the Suppression of Obesity-Associated Breast Cancer Cell Growth

Breast cancer is the most common cancer among women. Adiposity generally accompanies immune cell infiltration and cytokine secretion, which is ideal for tumor development. Aspirin is a chemopreventive agent against several types of cancer. The aim of this study was to investigate whether aspirin inhibits the growth of 4T1 breast cancer cells by inhibiting the inflammatory response and regulating the metabolomic profile of 3T3-L1 adipocytes. 3T3-L1 adipocyte-conditioned medium (Ad-CM) was used to mimic the obese adipose tissue microenvironment in 4T1 cells. The results revealed that aspirin inhibited macrophage chemoattractant protein (MCP-1), interleukin (IL-6), IL-1β, and plasminogen activator inhibitor (PAI-1) production in 3T3-L1 adipocytes stimulated by tumor necrosis factor-alpha (TNF-α) and lipopolysaccharide (LPS). In the obesity-associated model, Ad-CM significantly promoted 4T1 cell growth and migration, which were attenuated after aspirin treatment. The results of metabolic analyses using Ad-CM showed that amino acid metabolites and oxidative stress were increased in mature 3T3-L1 adipocytes compared to those in fibroblasts. Aspirin treatment modified metabolites involved in suppressing lipogenesis, oxidative stress, and neoplastic formation. In the relative fatty acid quantitation analysis of Ad-CM, aspirin diminished fatty acid contents of C16:1, C18:1, C18:2, C20:4, and C24:1. This study is the first to show that aspirin modifies the metabolomics and fatty acid composition of 3T3-L1 adipocytes and inhibits obesity-associated inflammation that contributes to obesity-related breast cancer cell growth and migration.