Search Results (163)

Poly-L-lactic acid (PLLA) filler, which increases volume and collagen synthesis, is used for skin rejuvenation. Subcutaneous adipose tissue (SAT) contains precursors that differentiate into mature adipocytes that secrete adiponectin, which modulates SAT function and increases adipogenesis. During aging, adiponectin and precursor cell functions decrease, reducing adipogenesis and facial volume. Adiponectin also increases collagen synthesis by stimulating fibroblasts. After hydrogen peroxide treatment to induce senescent adipocytes (3T3-L1) and aged skin, follow-up PLLA treatment increased adipogenesis by stimulating the nuclear factor erythroid-2-related factor 2 (NRF2)/peroxisome proliferator-activated receptor gamma (PPARγ)/CCAAT/enhancer binding protein alpha (C/EBPα) pathway. This resulted in increased adiponectin secretion, which promoted collagen synthesis and mitigated the loss of SAT volume. In the senescent adipocyte, PLLA increased NRF2/PPARγ/C/EBPα, adipogenesis factors (fatty acid binding protein 4, lipoprotein lipase, and cluster of differentiation 36), lipogenesis factors (ATP citrate lyase, acetyl-CoA carboxylase, and fatty acid synthase), adiponectin, and lipid droplet size. Treatment of senescent fibroblasts with conditioned medium from PLLA-treated adipocytes increased collagen1 and 3 and decreased matrix metalloproteinase1 and 3 expressions. Similarly, PLLA increased NRF2/PPARγ/C/EBPα, adipogenesis, and lipogenesis factors in aged mouse SAT. Also, PLLA increased adiponectin and adipocyte numbers without hypertrophy and increased collagen accumulation and dermal thickness. In summary, PLLA increased adipogenesis and adiponectin, which increased the volume of SAT and collagen synthesis, thereby rejuvenating aged skin. Full article

Background/Objectives: Obesity is a chronic and multifactorial disease that affects billions of people, and among the factors responsible for obesity are a sedentary lifestyle, a high-calorie diet, and genetic factors. Excessive caloric intake causes adipocyte hypertrophy and hyperplasia, contributing to the secretion of metabolically active molecules, known as adipokines, by adipose tissue. Individuals living with obesity have increased pro-inflammatory adipokines and a reduction in anti-inflammatory adipokines. Nuts contain bioactive compounds associated with potential health benefits, although these effects may vary depending on individual and dietary factors. Thus, this work aimed to critically review the impact of consuming almonds, walnuts, and mixed nuts on the production of adipokines associated with obesity and overweight. Methods: A comprehensive search was carried out using the terms associated with the theme of the work. The inclusion criteria for manuscripts used were the following: (1) in vivo studies; (2) intervention with oilseeds (nuts); (3) results related to adipokines and/or obesity; and (4) publications in English. Results: Studies show that regular intake of nuts reduces total cholesterol levels, LDL-c, and triglycerides and increases HDL-c in individuals with obesity. However, few studies demonstrate changes in adipokine levels related to the intake of nuts. A larger amount of 30 g of mixed nuts appears to be more beneficial for regulating adipokines in overweight or obese individuals than using nuts in larger amounts or isolated form. Of all the adipokines reported, only the results for IL-6 appear consistent, while the others remain unclear. Conclusions: Furthermore, more studies focusing specifically on this topic and humans are needed to draw greater conclusions, including the amount that results in a beneficial effect on health. Full article

Adiponectin (APN) is a secreted adipokine that plays a key role in modulating energy and bone metabolism, as well as regulating inflammatory responses. The overexpression of APN has been proposed as a potential therapeutic strategy for treating obesity and related disorders. Lipid nanoparticles (LNPs) are promising vectors for transporting messenger ribonucleic acid (mRNA) molecules. This study tested whether delivering a stabilized version of adiponectin mRNA (APN mRNA) using lipid nanoparticles could reduce fat formation and promote bone repair in vitro and in vivo. We demonstrated that transfection with APN-LNP upregulated the mRNA and protein expression of APN, while inhibiting adipogenesis in 3T3-L1 adipocytes. APN-LNP enhanced osteogenic gene expression in MC3T3-E1 cells in a dose-dependent manner. It also reduced matrix metalloproteinase 9 expression in receptor activator of nuclear factor-kappaB ligand (RANKL)-stimulated RAW264.7 cells, suggesting an anti-resorptive effect. In vivo, a femoral fracture model was established to explore the application of APN-LNP in promoting bone healing in diet-induced obese mice. Micro-computed tomography and histology analysis indicated that intravenous injection with APN-LNP promoted bone healing. Fasting blood glucose and body weight were decreased in the APN-LNP group. Moreover, APN-LNP increased bone sialoprotein and runt-related transcription factor 2 expression in contralateral femurs, as well as interleukin-10 expression in white adipose tissues. Thus, our study provides promising preclinical data on the potential use of APN-LNP for treating bone disorders in obesity. Full article

In patients diagnosed with multiple myeloma (MM), the primary complaints at the time of diagnosis are often related to bone involvement, significantly impacting quality of life and increasing both morbidity and mortality. Obesity is associated with a chronic inflammatory state that results in the production of various cytokines and adipokines, which may promote bone destruction. Adiponectin, an adipokine predominantly secreted by adipocytes, is notably diminished in circulation among individuals with obesity, a phenomenon that has also been observed in MM. This reduction may contribute to the disruption of an already compromised bone architecture. The increase in adipose tissue is associated with heightened leptin production, a key adipokine, which can play a significant role in the pathophysiology of MM and its related bone complications. Obesity is associated with hyperinsulinemia and increased levels of free IGF-1. In MM, IGF-1 plays a critical role as a growth factor, produced by both myeloma cells and osteoclasts within the bone marrow microenvironment. Our gathered data indicates a significant relationship between the adipokines produced by adipose tissue and the bone matrix, particularly in the context of obesity and MM. However, it is important to note that the existing body of research on this topic is relatively sparse, with the majority of studies conducted on murine models rather than human subjects. This limitation highlights a critical need for further investigation to elucidate the precise mechanisms that contribute to bone destruction under these conditions. Full article

High-mobility group box 1 (HMGB1) is a nuclear protein that can be secreted or released into the extracellular environment during cellular stress, functioning as a damage-associated molecular pattern molecule. This study investigates the role of HMGB1 in adipocyte development and metabolism, explicitly examining its interaction with β3-adrenergic receptor-mediated lipolysis and caveolin-1 (CAV1) regulation, which may influence cardiovascular risk factors. Using 3T3-L1 preadipocytes and mouse embryonic fibroblasts, we demonstrated that HMGB1 expression increases progressively during adipogenesis, reaching peak levels in mature adipocytes. While exogenous HMGB1 treatment did not affect preadipocyte proliferation or differentiation, it inhibited lipolysis in mature adipocytes. Mechanistically, HMGB1 suppressed β3-adrenergic receptor agonist CL-316,243-induced hormone-sensitive lipase activation by reducing protein kinase A-mediated phosphorylation and attenuating extracellular signal-regulated kinase signaling without affecting upstream cyclic AMP levels. We discovered a novel regulatory mechanism wherein CAV1 physically interacts with HMGB1 in mature adipocytes, with c-Src-dependent CAV1 phosphorylation functioning as a negative regulator of HMGB1 secretion. This finding was confirmed in CAV1-deficient models, which displayed increased HMGB1 secretion and diminished lipolytic activity both in vitro and in vivo. Furthermore, administering HMGB1-neutralizing antibodies to wild-type mice enhanced fasting-induced lipolysis, establishing circulating HMGB1 as a crucial antilipolytic factor. These findings reveal HMGB1’s previously uncharacterized role in adipose tissue metabolism as a negative regulator of lipolysis through CAV1-dependent mechanisms. This work provides new insights into adipose tissue metabolism regulation and identifies potential therapeutic targets for obesity-related metabolic disorders and cardiovascular diseases. Full article

Visceral fat mass is associated with a condition of chronic inflammation and can predispose the overweight to an increased cancer risk. Although it is known that adipocytes are active producers of the pro-inflammatory transforming growth factor β (TGFβ), the causes of their excessive synthesis are not clear. In this study, we reproduced two metabolic stress conditions frequently occurring in vivo, namely hypoxia and the fatty acid-driven metabolic uncoupling, and we characterized the response of an in vitro model of 3T3-L1 mouse adipocytes. For the first time, we demonstrated that the mitochondrial dysmetabolism of differentiated adipocytes induced the secretion of TGFβ. The paracrine activity of the secreted cytokine was then tested on two human pancreatic cancer cell lines. Cancer cells responded to the stimulation by increasing mitochondrial respiration, switching on the epithelial–mesenchymal transition (EMT) program and enhancing their motility. The data obtained in this proof-of-concept research show that TGFβ can be produced by dysmetabolic adipocytes, linking the altered metabolism with pro-tumorigenic inflammation. The novel observations of this study identify in metabolic stress a still unexplored cause of inflammation and cancer progression and pave the way to more detailed in vitro and clinical studies on pancreatic cancer. Full article

Background: Aromatase inhibitors-related musculoskeletal syndrome (AIMSS) is a common side effect experienced by early breast cancer patients undergoing endocrine therapy. This condition can result in medication discontinuation and a diminished quality of life. The objective of this study was to characterize AIMSS, investigate its pathogenesis, and identify potential biomarkers at both the protein and metabolic levels. Methods: We collected peripheral blood samples from 60 women diagnosed with breast cancer undergoing aromatase inhibitor therapy, of whom 30 had AIMSS and 30 did not. The samples were analyzed using four-dimensional data-independent acquisition (DIA)-based proteomics and untargeted metabolomics, employing liquid chromatography–mass spectrometry (LC–MS) on the latest platform. Results: The mean age of participants was 49.2 (11.3) years in the AIMSS group and 50.1 (11.5) years in the non-AIMSS group. There were no statistically significant differences between the two groups in terms of age, BMI, education level, clinical stage, and treatment. In total, we identified 3473 proteins and 1247 metabolites in the samples. The chemokine signaling pathway (p = 0.015), cytokine–cytokine receptor interaction (p = 0.015), complement and coagulation cascades (p = 0.004), neuroactive ligand–receptor interaction (p = 0.004), and the estrogen signaling pathway (p = 0.004) were significant enriched in differentially expressed proteins (DEPs). GnRH secretion (p < 0.001), sphingolipid signaling pathways (p < 0.001), endocrine resistance (p < 0.001), the estrogen signaling pathway (p = 0.001), endocrine and other factor-regulated calcium reabsorption (p = 0.001), dopaminergic synapse (p = 0.003), regulation of lipolysis in adipocytes (p = 0.004), biosynthesis of cofactors (p = 0.004), thyroid hormone synthesis (p = 0.008), aldosterone synthesis and secretion (p = 0.001), taurine and hypotaurine metabolism (p = 0.011), ovarian steroidogenesis (p = 0.011), and the cAMP signaling pathway (p = 0.011) were significantly enriched in differentially expressed metabolites (DEMs). Complement C3 (p = 0.004), platelet factor 4 (p = 0.015), KRT10 (p = 0.004), KRT14 (p = 0.004), beta-estradiol (p = 0.019), testosterone (p = 0.023), sphingosine (p < 0.001), and 1-stearoyl-2-arachidonoyl-sn-glycerol (p = 0.039) could be the monitoring and therapeutic targets for AIMSS. Conclusions: This study offered new insights into the mechanisms underlying musculoskeletal symptoms associated with aromatase inhibitors. It also highlighted potential biomarkers for predicting and addressing these symptoms in breast cancer patients, paving the way for improved intervention strategies. Full article

The mortality rate of ovarian cancer (OC) remains the highest among female gynecological malignancies. Advanced age is the highest risk factor for OC development and progression, yet little is known about the role of the aged tumor microenvironment (TME). We conducted RNA sequencing and lipidomic analysis of young and aged gonadal adipose tissue from rat xenografts before and after OC formation. The rates of tumor formation (p = 0.047) and tumor volume (p = 0.002) were significantly higher in the aged rats than in their young counterparts. RNA sequencing data showed significant differences in gene expression profiles between the groups of young and aged rat adipose tissues (p < 0.05), including S100a8, S100a9, Il1rl1, Lcn2, C3, Hba-a1, Fcna, and Pnpla3. At the time of tumor generation, there were also changes in the lipid components within the gonadal adipose tissues of young and aged rats, with higher levels of free fatty acids (FFAs) and triglycerides (TGs) in aged rats. Furthermore, the aged TME showed changes in immune cell composition, especially inflammation-related cells, including neutrophils, myeloid dendritic cells, CD4+ T cells (non-regulatory), and mast cell activation (p < 0.05). The correlation between S100a8, S100a9, neutrophil, and omega-5, FFA 18:3 levels was also determined. Additionally, omega-5, which is downregulated in aged rats, inhibited OC cell proliferation in vitro (p < 0.001). Our study suggests that the aged TME promotes OC proliferation resulting from age-related changes in gene/pathway expression, lipid metabolism, and immune cell distribution. Targeting the aging adipose microenvironment, particularly lipid metabolism, is a promising therapeutic strategy for OC and warrants further investigation. Significance: The aging microenvironment contributes to OC development and progression because of changes in the immune response regulatory genes S100a8 and S100a9, secreted by adipocytes, preadipocytes, or neutrophils, and by altering omega-5 metabolism. Full article

Background/Objectives: LL-37 is associated with metabolic syndrome (MetS), a constellation of risk factors comprising obesity, insulin resistance (IR), dyslipidemia, and hypertension, which elevates the risk of cardiovascular disease and type 2 diabetes. Methods: In this narrative review, we analyzed the literature focusing on recent developments in the relationship between cathelicidin and various components of MetS to provide a comprehensive overview. Results: Studies have shown that LL-37 is linked to inflammation in adipose tissue (AT) and the development of IR in obesity. Cathelicidin can enhance inflammation by activating pro-inflammatory genes, as well as modulate the inflammatory response. The mechanisms of IR include the activation of complex signaling pathways that induce inflammation and reduce insulin signaling in adipocytes. The activation of Toll-like receptors (TLRs) by cathelicidin stimulates the secretion of pro-inflammatory cytokines, contributing to the disruption of insulin function in adipose cells. Cathelicidin also influences lipid metabolism, with recent research showing a negative relationship between LL-37 levels and HDL cholesterol. Therefore, LL-37 is involved not only in the regulation of inflammation but also in lipid metabolism, potentially aggravating the cardiovascular complications associated with MetS. Conclusions: Cathelicidin plays a crucial role in regulating the balance between inflammatory and anti-inflammatory responses in MetS. Understanding the impact of LL-37 on these mechanisms may unveil novel approaches for addressing MetS and its associated complications. Full article

Background: Microbial fermentation of non-digestible carbohydrates and/or protein produces short-chain fatty acids (SCFA), whereas branched-chain fatty acids (BCFA) are produced from protein fermentation. The effects of individual SCFA and BCFA of comparable carbon chain length on adipocyte inflammation have not been investigated. Objective: To compare the effects of SCFA and BCFA on inflammatory mediator secretion in an adipocyte cell culture model designed to recapitulate obesity-associated adipocyte inflammation under normoxic and hypoxic conditions. Methods: The 3T3-L1 adipocytes were cultured (24 h) without (Control, Con) and with 1 mmol/L of SCFA (butyric acid (But) or valeric acid (Val)) or 1 mmol/L of BCFA (isobutyric acid (IsoBut) or isovaleric acid (IsoVal)) and were unstimulated (cells alone, n = 6/treatment), or stimulated with 10 ng/mL lipopolysaccharide (LPS, inflammatory stimulus, n = 8/treatment) or 10 ng/mL LPS + 100 µmol/L of the hypoxia memetic cobalt chloride (LPS/CC, inflammatory/hypoxic stimulus, n = 8/treatment). Results: Compared to Con + LPS, But + LPS reduced secreted protein levels of interleukin (IL)-1β, IL-6, macrophage chemoattractant protein (MCP)-1/chemokine ligand (CCL)2, MCP3/CCL7, macrophage inflammatory protein (MIP)-1α/CCL3 and regulated upon activation, normal T cell expressed, and secreted (RANTES)/CCL5 and decreased intracellular protein expression of the ratio of phosphorylated to total signal transducer and activator of transcription 3 (STAT3) and nuclear factor kappa B (NFκB) p65 (p < 0.05). Val + LPS reduced IL-6 secretion and increased MCP-1/CCL2 secretion compared to Con + LPS and exhibited a different inflammatory mediator secretory profile from But + LPS (p < 0.05), indicating that individual SCFA exert individual effects. There were no differences in the secretory profile of the BCFA IsoBut + LPS and IsoVal + LPS (p > 0.05). Alternatively, under inflammatory hypoxic conditions (LPS/CC) Val, IsoVal, and IsoBut all increased secretion of IL-6, MCP-1/CCL2 and MIP-1α/CCL3 compared to Con (p < 0.05), whereas mediator secretion did not differ between But and Con (p > 0.05), indicating that the proinflammatory effects of SCFA and BCFA was attenuated by But. Interestingly, But + LPS/CC decreased STAT3 activation versus Con + LPS/CC (p < 0.05). Conclusions: The decreased secretion of inflammatory mediators that is attributable to But highlights the fact that individual SCFA and BCFA exert differential effects on adipocyte inflammation under normoxic and hypoxic conditions. Full article

Background: Arrhythmogenic cardiomyopathy (ACM) is a genetic disorder responsible for nearly a quarter of sports-related sudden cardiac deaths. ACM cases caused by mutations in desmosome proteins lead to right ventricular enlargement, the loss of cardiomyocytes, and fibrofatty tissue replacement, disrupting electrical and mechanical stability. It is currently unknown how paracrine factors secreted by infiltrating fatty tissues affect ACM cardiomyocyte electrophysiology. Methods: A normal and a PKP2 mutant (c.971_972InsT) ACM hiPSC line were cultivated and differentiated into cardiomyocytes (CMs). Adipocytes were differentiated from human adipose stem cells, and adipocyte conditioned medium (AdCM) was collected. Optical mapping and phenotypic analyses were conducted on human iPSC-cardiomyocytes (hiPSC-CMs) cultured in cardiac maintenance medium (CMM) and either with AdCM or specific cytokines. Results: Significant differences were observed in voltage parameters such as the action potential duration (APD₈₀, APD₃₀), conduction velocity (CV), and CV heterogeneity. When cultured in AdCM relative to CMM, the APD₈₀ increased and the CV decreased significantly in both groups; however, the magnitudes of changes often differed significantly between 1 and 7 days of cultivation. Cytokine exposure (IL-6, IL-8, MCP-1, CFD) affected the APD and CV in both the normal and PKP2 mutant hiPSC-CMs, with opposite effects. NF-kB signaling was also found to differ between the normal and PKP2 mutant hiPSC-CMs in response to AdCM and IL-6. Conclusions: Our study shows that hiPSC-CMs from normal and mPKP2 ACM lines exhibit distinct molecular and functional responses to paracrine factors, with differences in RNA expression and electrophysiology. These different responses to paracrine factors may contribute to arrhythmogenic propensity. Full article

Background/Objectives: Adiponectin, the most abundant peptide hormone secreted by adipocytes, is a well-known homeostatic factor regulating lipid metabolism and insulin sensitivity. It has been shown that the adiponectin receptor agonist AdipoRon selectively enhances cellular responses to fatty acids in human taste cells, and adiponectin selectively increases taste behavioral responses to intralipid in mice. However, the molecular mechanism underlying the physiological effects of adiponectin on fat taste in mice remains unclear. Conclusions: Here we define AdipoR1 as the mediator responsible for the enhancement role of adiponectin/AdipoRon on fatty acid-induced responses in mouse taste bud cells. Methods and Results: Calcium imaging data demonstrate that AdipoRon enhances linoleic acid-induced calcium responses in a dose-dependent fashion in mouse taste cells isolated from circumvallate and fungiform papillae. Similar to human taste cells, the enhancement role of AdipoRon on fatty acid-induced responses was impaired by co-administration of an AMPK inhibitor (Compound C) or a CD36 inhibitor (SSO). Utilizing Adipor1-deficient animals, we determined that the enhancement role of AdipoRon/adiponectin is dependent on AdipoR1, since AdipoRon/adiponectin failed to increase fatty acid-induced calcium responses in taste bud cells isolated from these mice. Brief-access taste tests were performed to determine whether AdipoRon’s enhancement role was correlated with any differences in taste behavioral responses to fat. Although AdipoRon enhances the cellular responses of taste bud cells to fatty acids, it does not appear to alter fat taste behavior in mice. However, fat-naïve Adipor1^−/− animals were indifferent to increasing concentrations of intralipid, suggesting that adiponectin signaling may have profound effects on the ability of mice to detect fatty acids in the absence of previous exposure to fatty acids and fat-containing diets. Full article

Osteoporosis is a common skeletal disease, primarily associated with aging, that results from decreased bone density and bone volume. This reduction significantly increases the risk of fractures in osteoporosis patients compared to individuals with normal bone density. Additionally, the bone regeneration process in these patients is slow, making complete healing difficult. Along with the decline in bone volume and density, osteoporosis is characterized by an increase in marrow adipose tissue (MAT), which is fat within the bone. In this altered bone microenvironment, osteoblasts are influenced by various factors secreted by adipocytes. Notably, saturated fatty acids promote osteoclast activity, inhibit osteoblast differentiation, and induce apoptosis, further reducing osteoblast formation. In contrast, monounsaturated fatty acids inhibit osteoclast formation and mitigate the apoptosis caused by saturated fatty acids. Leveraging these properties, we aimed to investigate the effects of overexpressing stearoyl-CoA desaturase 1 (SCD1), an enzyme that converts saturated fatty acids into monounsaturated fatty acids, on osteogenic differentiation and bone regeneration in both in vivo and in vitro models. Through this novel approach, we seek to develop a stem cell-based therapeutic strategy that harnesses SCD1 to improve bone regeneration in the adipocyte-rich osteoporotic environment. Full article

The high prevalence of diabetes mellitus (DM) poses a significant public health challenge, with diabetic kidney disease (DKD) as one of its most serious consequences. It has become increasingly clear that type 2 DM (T2D) and the complications of DKD are not purely metabolic disorders. This review outlines emerging evidence related to the step-by-step contribution of macrophages to the development and progression of DKD in individuals who specifically develop T2D as a result of obesity. The macrophage is a prominent inflammatory cell that contributes to obesity, where adipocyte hypertrophy leads to macrophage recruitment and eventually to the expansion of adipose tissue. The recruited macrophages secrete proinflammatory cytokines, which cause systemic inflammation, glucose dysregulation, and insulin sensitivity, ultimately contributing to the development of T2D. Under such pathological changes, the kidney is susceptible to elevated glucose and thereby activates signaling pathways that ultimately drive monocyte recruitment. In particular, the early recruitment of proinflammatory macrophages in the diabetic kidney produces inflammatory cytokines/chemokines that contribute to inflammation and tissue damage associated with DKD pathology. Macrophage activation and recruitment are crucial inciting factors that also persist as DKD progresses. Thus, targeting macrophage activation and function could be a promising therapeutic approach, potentially offering significant benefits for managing DKD at all stages of progression. Full article

Breast cancer (BC) represents the most prevalent cancer in women at any age after puberty. From a pathogenetic prospective, despite a wide array of risk factors being identified thus far, poor metabolic health is emerging as a putative risk factor for BC. In particular, type 2 diabetes mellitus (T2DM) provides a perfect example bridging the gap between poor metabolic health and BC risk. Indeed, T2DM is preceded by a status of hyperinsulinemia and is characterised by hyperglycaemia, with both factors representing potential contributors to BC onset and progression. Additionally, the aberrant secretome of the dysfunctional, hypertrophic adipocytes, typical of obesity, characterised by pro-inflammatory mediators, is a shared pathogenetic factor between T2DM and BC. In this review, we provide an overview on the effects of hyperglycaemia and hyperinsulinemia, hallmarks of type 2 diabetes mellitus, on breast cancer risk, progression, treatment and prognosis. Furthermore, we dissect the role of the adipose-tissue-secreted adipokines as additional players in the pathogenesis of BC. Finally, we focus on microalgae as a novel superfood and a source of nutraceuticals able to mitigate BC risk by improving metabolic health and targeting cellular pathways, which are disrupted in the context of T2DM and obesity. Full article