Search Results (136)

Xylosyltransferase-I (XT-I) plays a crucial role in skeletal development and cartilage integrity. An XT-I deficiency is linked to severe bone disorders, such as Desbuquois dysplasia type 2. While animal models have provided insights into XT-I’s role during skeletal development, its specific effects on adult bone homeostasis, particularly in human mesenchymal stem cell (hMSC) differentiation, remain unclear. This study investigates how XT-I deficiency impacts the differentiation of hMSCs into chondrocytes, osteoblasts, and adipocytes—key processes in bone formation and repair. The aim of this study was to elucidate for the first time the molecular mechanisms by which XT-I deficiency leads to impaired bone homeostasis. Using CRISPR-Cas9-mediated gene editing, we generated XYLT1 knockdown (KD) hMSCs to assess their differentiation potential. Our findings revealed significant disruption in the chondrogenic differentiation in KD hMSCs, characterized by the altered expression of regulatory factors and extracellular matrix components, suggesting premature chondrocyte hypertrophy. Despite the presence of perilipin-coated lipid droplets in the adipogenic pathway, the overall leptin mRNA and protein expression was reduced in KD hMSCs, indicating a compromised lipid metabolism. Conversely, osteogenic differentiation was largely unaffected, with KD and wild-type hMSCs exhibiting comparable mineralization processes, indicating that critical aspects of osteogenesis were preserved despite the XYLT1 deficiency. In summary, these results underscore XT-I’s pivotal role in regulating differentiation pathways within the bone marrow niche, influencing cellular functions critical for skeletal health. A deeper insight into bone biology may pave the way for the development of innovative therapeutic approaches to improve bone health and treat skeletal disorders. Full article

In the era of combined antiretroviral therapy, around 50% of chronic HIV (+) individuals show varying degrees of memory and cognitive deficiency (NeuroHIV), a phenomenon of accelerated brain aging. HIV protein transactivator of transcription (TAT) has been well-accepted as a risk factor contributing to NeuroHIV through dysregulating microglia (Mg) functions. Previous studies have demonstrated that HIV-TAT can affect lipid metabolism, immune responses, autophagy, and senescence in rodent Mg. However, due to the significant species differences between rodent and human Mg (hMg), it is essential to take caution when interpreting the results obtained from rodent models into human conditions. For the unanswered questions, we generated hMg from human inducible pluripotent stem cells (iPSCs) and exposed them to HIV-TAT. The results obtained from Flow analysis and immunostaining experiments reveal that TAT can induce LD accumulation and increase perilipin-2 (Plin2) levels in hMg. Meanwhile, HIV-TAT can upregulate autophagosome formation and p53 levels. Through human immune array assay, we showed that TAT can increase the expression of multiple pro-inflammatory mediators, cytokines, and chemokines in hMg. Extensive bioinformatic analysis shows that HIV-TAT can affect multiple neuroimmune signaling pathways and indicates that microRNAs (miRNAs) are coherently involved in such dysregulation. Overall, our findings provide direct evidence showing that HIV-TAT can affect lipid metabolism, autophagy, senescence signaling, and multiple neuroimmune-related pathways in hMg and indicate the roles of novel miRNAs on NeuroHIV pathogenesis, which deserves further investigations. Full article

Background: Histological and immunohistochemical analyses of adipose tissue are essential for evaluating the quality and functionality of lipoaspirates in regenerative medicine and fat grafting procedures. These methods provide insights into tissue viability, cellular subtypes, and extracellular matrix (ECM) composition—all factors influencing graft retention and clinical outcomes. Purpose: This scoping review aims to summarize the most commonly used staining methods and their applications in the histology and immunohistochemistry of adipose tissue. By exploring qualitative and quantitative markers, we seek to guide researchers in selecting the appropriate methodologies for addressing experimental and translational research. Methods: A systematic search was conducted using PubMed, Ovid, and the Cochrane Library databases from inception to 2024, employing Boolean operators (“lipoaspirate” OR “fat graft” OR “gauze rolling” OR “decantation” OR “coleman fat” OR “celt” OR “nanofat” OR “lipofilling” OR “human fat” AND “histol*”). Studies were included if they utilized histology or immunohistochemistry on undigested human adipose tissue or its derivatives. The inclusion criteria focused on peer-reviewed, English-language studies reporting quantitative and qualitative data on adipose tissue markers. Results: Out of 166 studies analyzed, hematoxylin–eosin (H&E) was the most frequently employed histological stain (152 studies), followed by Masson Trichrome and Sudan III. Immunohistochemical markers such as CD31, CD34, and perilipin were extensively used to distinguish stromal vascular fraction (SVF) cells, adipocytes, and inflammatory processes. Studies employing semiquantitative scoring demonstrated enhanced comparability, particularly for fibrosis, necrosis, and oil cyst evaluation. Quantitative analyses focused on SVF cell density, mature adipocyte integrity, and ECM composition. Methodological inconsistencies, particularly in preparation protocols, were observed in 25 studies. Conclusions: This review highlights the critical role of histological and immunohistochemical methods in adipose tissue research. H&E staining remains the cornerstone for general tissue evaluation in the clinical context, while specialized stains and immunohistochemical markers allow for detailed analyses of specific cellular and ECM components in experimental research. Standardizing preparation and evaluation protocols will enhance interstudy comparability and support advancements in adipose tissue-based therapies. Full article

Unwanted abdominal fat is a common aesthetic concern treated through various interventions, including surgical and energy-based devices, often leading to inconsistent results. This study aimed to evaluate the feasibility of a localized, non-invasive microwave (MW) device for preferential heating of subcutaneous adipose tissue using a controlled electromagnetic field. Five female volunteers scheduled for abdominoplasty were enrolled, each undergoing a single MW treatment session five days prior to surgery. Histological analyses of adipose tissue and skin samples were conducted using Hematoxylin and Eosin staining and immunohistochemistry for Perilipin-1 and CD68. Epidermal and dermal layers remained unaffected, as evidenced by unaltered morphology in treated samples. In contrast, the absence of Perilipin-1 expression in disrupted fat cell membranes indicated adipocyte non-viability and irreversible injury. Inflammatory responses, including CD68-positive macrophages surrounding damaged adipocytes, were observed, suggesting the activation of the monocyte/macrophage system for the clearance of adipocyte residues. Microscopic and immunohistochemical findings demonstrate the effectiveness of the MW device in reducing subcutaneous fat. This study also discussed the underlying mechanisms involved in macrophage recruitment and the removal of adipocyte residues. Full article

Lipotoxicity, resulting from the buildup of excess lipids in non-adipose tissues, is increasingly recognized as a major contributor to the progression of kidney disease, highlighting the need for alternative models to assess its effects on renal cells. The main aim of this study was to investigate the usefulness of Caki-1, a human proximal tubule (PT) and renal cell carcinoma (RCC) representative cell line, as a 3D model system for studying free fatty acid-induced PT lipotoxicity. Caki-1 spheroids were generated and maintained on ultra-low attachment plates and characterized regarding time-dependent morphology changes. In optimal 3D culture conditions, Caki-1 cells formed well-defined large compact spheroids with uniform morphology, good circularity, and increased diameter from days 4–12. Chronic exposure to saturated palmitate resulted in dose- and time-dependent spheroid disintegration and cell death, including dispersed and flattened spheroid morphology, with increased dead cells in the peripheral layers and decreased spheroid core. Moreover, palmitate-treated spheroids showed a significant increase in cleaved poly(ADP-ribose) polymerase (PARP) and active caspase-3. Palmitate-induced PARP cleavage, as well as endoplasmic reticulum (ER) stress and autophagy dysfunction, were blunted by triacsin C, an inhibitor of long-chain acyl-CoA synthetases. In addition, co-incubation with unsaturated oleate prevented palmitate-induced spheroid disintegration and apoptotic cell death in Caki-1 3D culture. While fatty acid overload upregulated lipid droplet protein perilipin 2 in Caki-1 cells, knockdown of perilipin 2 by siRNAs resulted in an exacerbation of palmitate-induced cell death. Together, these results indicate that the 3D Caki-1 spheroid model is a simple and reproducible in vitro system for studying renal lipotoxicity and lipid metabolism that gives useful readouts at the molecular, cellular, and multicellular levels. Full article

Previous reports have described a statistical association between high-density lipoproteins (HDL) subclasses and the expression of genes coding for pro-calcifying proteins in the epicardial adipose tissue of patients with coronary artery disease (CAD) and aortic valvular stenosis (AVS). These results suggest a causal relationship between HDL and the regulation of gene expression in epicardial adipose tissue. However, there is no experimental evidence that supports this causal relationship. Therefore, we explored the effect of HDL isolated from CAD or AVS patients on the expression of OPN, BMP2, and BMP4, genes coding for proteins related to calcification, osteopontin, and bone morphogenetic proteins -2 and -4, respectively, and LEP, UCP, and PER, coding for leptin, uncoupling protein-1, and perilipin-2, respectively, proteins that confer phenotypic characteristics to adipocytes. The experiments were performed using a novel model of cardiac adipocytes differentiated in vitro from stromal cells of rabbit cardiac adipose tissue. AVS or CAD patients’ HDL differentially modulated the expression of BMP4 and LEP, whereas HDL from both kinds of patients upregulated the OPN gene expression. A high concentration of triglycerides associated to small HDL and a higher concentration of phospholipids of large HDL from CAD patients than those from AVS individuals were the most remarkable structural differences. Finally, we demonstrated that cholesterol from reconstituted HDL was internalized to the adipocytes. The regulation of genes related to the secretory activity of cardiac adipocytes mediated by HDL has clinical implications as a potential therapeutic target for the prevention and treatment of CAD and AVS. In summary, the HDL isolated from the CAD and AVS patients differentially regulated gene expression in adipocytes by a mechanism that seems to be dependent on HDL lipid internalization to the cells and structural characteristics of the lipoproteins. Full article

Melatonin is involved in various functions such as the timing of circadian rhythms, energy metabolism, and body mass gain in experimental animals. However, its effects on adipose tissue lipid metabolism are still unclear. This study analyzes the effects of melatonin on the relative gene expression of lipolytic proteins in rat mesenteric adipose tissue and free fatty acid (FFA) and glycerol plasma levels of male Wistar rats fed a high-fat (HFD) or maintenance diet. Four experimental groups were established: control, obese, and control or obese plus 2.3 mg/kg/day of melatonin in tap water. After 11 weeks, animals were sacrificed at different times throughout a 24 h cycle, and mesenteric adipose tissue and plasma samples were collected and analyzed. Cgi58, Perilipin, and Dgat1 gene expression, as well as FFA and glycerol concentrations, showed rhythm patterns in the control group. HFD disrupted those rhythm patterns and increased FFA and glycerol concentrations during the dark photoperiod. In both melatonin-treated groups, almost all analyzed genes showed circadian patterns. Notably, melatonin significantly prevented the increase in FFA levels during the dark photoperiod in obese rats (obese group: ~1100 mM vs. obese + melatonin group: ~600 μM, similar to control levels). However, the rhythmic pattern observed in control animals was not sustained. According to our results, melatonin could regulate circadian gene transcription of mesenteric adipose tissue lipolysis proteins. The effect of melatonin on preventing elevated FFA plasma levels associated with high-fat diet intake warrants further investigation. Full article

Lipid droplets (LDs), highly dynamic cellular organelles specialized in lipid storage and maintenance of lipid homeostasis, contain several proteins on their surface, among which the perilipin (Plin) family stands out as the most abundant group of LD-binding proteins. They play a pivotal role in influencing the behavior and functionality of LDs, regulating lipase activity, and preserving a balance between lipid synthesis and degradation, which is crucial in the development of obesity and abnormal accumulation of fat in non-adipose tissues, causing negative adverse biological effects, such as insulin resistance, mitochondrial dysfunction, and inflammation. The expression levels of Plins are often associated with various diseases, such as hepatic steatosis and atherosclerotic plaque formation. Thus, it becomes of interest to investigate the Plin roles by using appropriate “omics” approaches that may provide additional insight into the mechanisms through which these proteins contribute to cellular and tissue homeostasis. This review is intended to give an overview of the most significant omics studies focused on the characterization of Plin proteins and the identification of their potential targets involved in the development and progression of cardiovascular and cardiometabolic complications, as well as their interactors that could be useful for more efficient therapeutic and preventive approaches for patients. Full article

Optimizing fat deposition is crucial for improving chicken production and meat quality. This study investigated the interactive roles of host genetics and gut microbiome in regulating abdominal fat deposition in selectively bred broiler chicken lines. We compared the gut microbiome composition and host whole-genome profiles between fat-line and lean-line broiler chickens that had been selectively bred for divergent abdominal fat levels over 15 generations. Despite identical dietary and environmental conditions, the two chicken lines exhibited significant differences in their gut microbiota. Lean-line broiler chickens exhibited an increased abundance of intestinal Lactobacillus and a decreased presence of potentially pathogenic species, such as Campylobacter coli, Corynebacterium casei, and Enterococcus faecalis. These microbial alterations were accompanied by shifts in the functional metagenome, with enrichment in pathways involved in energy metabolism and nutrient utilization in the lean-line chickens. Notably, the selective breeding process also led to genomic variations in the lean broilers, with single nucleotide polymorphisms predominantly observed in genes related to energy and lipid metabolism. Our findings suggest that the host–microbiome interactions play a key role in the divergent abdominal fat deposition phenotypes observed in these selectively bred chicken lines. The co-evolution of the gut microbiome and host genetics highlights the importance of considering both factors to optimize poultry production efficiency and meat quality. This study offers new insights into the intricate gut–genome interactions in chicken fat metabolism, paving the way for more effective breeding and microbiome-based strategies to manage adiposity in poultry. Full article

Metabolic dysfunction-associated fatty liver disease (MASLD) is a widespread liver disorder characterized by excessive fat accumulation in the liver, commonly associated with metabolic syndrome components such as obesity, diabetes, and dyslipidemia. With a global prevalence of up to 30%, MASLD is projected to affect over 100 million people in the U.S. and 20 million in Europe by 2030. The disease ranges from Steatotic Lived Disease (SLD) to more severe forms like metabolic dysfunction-associated steatohepatitis (MASH), which can progress to cirrhosis and hepatocellular carcinoma. Autophagy, a cellular process crucial for lipid metabolism and homeostasis, is often impaired in MASLD, leading to increased hepatic lipid accumulation and inflammation. Key autophagy-related proteins, such as Beclin1, LC3A, SQSTM1 (p62), CD36, and Perilipin 3, play significant roles in regulating this process. Disruption in these proteins contributes to the pathogenesis of MASLD. Quercetin, a natural polyphenolic flavonoid with antioxidant and anti-inflammatory properties, has promising results in mitigating MASLD. It may reduce hepatic lipid accumulation, improve mitochondrial function, and enhance autophagy. However, further research is needed to elucidate its mechanisms and validate its therapeutic potential in clinical settings. This underscores the need for continued investigation into autophagy and novel treatments for MASLD. Full article

Background: Obesity is a risk factor of several types of cancer, including breast cancer. In this study, we aimed to histologically characterize the adipose tissue of the tumor microenvironment (TME) of triple-negative breast cancer (TNBC) in overweight/obese versus normal-weight patients. Methods: TNBC tissue sections from normal-weight (BMI_<25) and overweight/obese patients (BMI_≥25) were stained with antibodies against CD68, CD163, CD31, CD34, and vimentin. At the invasive tumor front, positive cells were counted in tumor adjacent adipose tissue (AT) and within cancer tissue (CT). Further, the size of the tumor-adjacent and distant mammary adipocytes was determined in perilipin stained sections. Expression of ANGPTL4, CD36 and FABP4, proteins involved in fatty acid metabolism, was analyzed in marginal tumor cells using an immune reactive score. Results: Overweight/obese TNBC patients had significantly larger adipocytes, higher numbers of CD163+ macrophages (BMI_<25: 2.80 vs. BMI_≥25: 10.45; p = 0.011) and lower numbers of CD31+ (BMI_<25: 4.20 vs. BMI_≥25: 2.40; p = 0.018) and CD34+ (BMI_<25: 14.60 vs. BMI_≥25: 5.20; p = 0.045) cells as markers of angiogenesis in the AT as well as a higher frequency of cancer-associated-fibroblast-like cells in the AT and CT (BMI_<25: 7.60 vs. BMI_≥25: 25.39 in total; p = 0.001). Moreover, expression of CD36 (BMI_<25: 2.15 vs. BMI_≥25: 2.60; p = 0.041) and ANGPTL4 (BMI_<25: 6.00 vs. BMI_≥25: 9.80; p = 0.026) was elevated in the TNBC cells of overweight/obese patients. Conclusions: Our data suggest BMI-related changes in the TME of overweight/obese TNBC patients, including hypertrophied adipocytes, reduced vascularization, more M2-like macrophages and CAF-like cells, and an increase in the expression of fatty acid metabolizing proteins in marginal tumor cells, all contributing to a more tumor-promoting, immunosuppressive environment. Full article

The major components of magnolia flower extracts (MFEs) were classified into four substances, such as flavonoids, phenylethanoid glycoside derivatives (PhGs), caffeoylquinic acids (CQAs), and others, in our previous study. The chemical components of MFEs, including the rutin of flavonoid, acteoside and isoacteoside of PhGs, and caffeyolquinic acids, are reported to have physiological effects on anti-obesity effects. The anti-obesity effect of fresh and browned Magnolia denudata flower extracts (FMFE and BMFE, respectively) was investigated in 3T3-L1 adipocytes. The treatment concentrations of FMFE and BMFE were 200 and 400 μg/mL, respectively, as determined with the WST-1 assay. Intracellular lipid accumulation in 3T3-L1 cells was inhibited with the treatment of MFEs, including FMFE and BMFE, as observed with an image of the culture plate, using an optical microscope and Oil red O staining. The expression of the adipogenic target genes involved in adipocyte differentiation, including PPARγ, C/EBPα, perilipin, FABP4, FAS, HSL, and SREBP-1, was suppressed with the treatment of MFEs. Additionally, the phosphorylation of AMPK and ACC in 3T3-L1 cells was significantly increased following treatment with the MFEs. These results suggest that both MFEs have a potential for physiological effects on anti-obesity activity. Full article

Background/Objectives: Moringa oleifera is a matrix plant with the high potential to cure several diseases with its medicinal and ethnopharmacological value and nutraceutical properties. In this study, we investigated the chemical and biological properties of this plant cultivated in our local region. Methods: Leaves, roots, seeds, stem bark, and twigs of oleifera were extracted and evaluated bioactivities targeting intracellular lipid accumulation and adipocyte differentiation in 3T3-L1 preadipocytes, and UHPLC-ESI-Orbitrap-MS/MS-Based molecular networking guided isolation and dereplication of metabolites from these extracts. Results: Five extracts of different organs of M. oleifera significantly stimulated intracellular lipid accumulation and adipocyte differentiation in 3T3-L1 preadipocytes in a concentration-dependent manner. These extracts markedly increased the expression of genes related to adipogenesis and lipogenesis. Notably, these extracts promoted peroxisome proliferator-activated receptor γ (PPARγ) activity and the expression of its target genes, including phosphoenolpyruvate carboxykinase, fatty acid-binding protein 4, and perilipin-2. These adipogenic and lipogenic effects of Moringa extracts through the regulation of PPARγ activity suggests their potential efficacy in preventing or treating type 2 diabetes. Furthermore, chemical investigation revealed high contents of phytonutrients as rich sources of secondary metabolites including glycosides, flavones, fatty acids, phenolics, and other compounds. In addition, in silico studies on major components of these extracts revealed the bioavailability of major components through their binding affinity to respective proteins targeting adipocyte differentiation. Full article

Background: Perilipin 2 (PLIN2) is a protein that contributes to the formation and stability of lipid droplets. It has been associated with the development of several diseases, particularly related to glucose and lipid metabolism. In infants of diabetic mother (IDM), fetal hyperinsulinaemia leads to increased adipose tissue and macrosomia. The aim of this study was to investigate the relationship between PLIN2 levels and anthropometric measurements in the IDM and to investigate the relationship between PLIN2 levels and IGF-1, IGF-2 and leptin levels. Methods: The study group consisted of IDMs, while the control group consisted of infants born to non-diabetic mother, matched for gestational week and gender. Cord blood samples were collected from all patients to determine PLIN2, IGF-1, IGF-2 and leptin levels. Anthropometric measurements were taken for all patients at birth. Results: There were no differences between the groups in birth weight, birth length, head circumference and body mass index (BMI), but middle arm circumference, triceps, biceps, subscapular and suprailiac skinfold thickness were significantly higher in the IDM. While PLIN2, IGF-1, IGF-2 and leptin levels were similar between groups, there was a strong correlation between PLIN2 levels and IGF-2 and leptin levels. Conclusions: Even if IDMs were not macrosomic, the presence of high subcutaneous adipose tissue was not associated with PLIN2. Full article

Clinical ketosis is a detrimental metabolic disease in dairy cows, often accompanied by severe lipolysis and inflammation in adipose tissue. Our previous study suggested a 2.401-fold upregulation in the calmodulin (CaM) level in the adipose tissue of cows with clinical ketosis. Therefore, we hypothesized that CaM may regulate lipolysis and inflammatory responses in cows with clinical ketosis. To verify the hypothesis, we conducted a thorough veterinary assessment of clinical symptoms and serum β-hydroxybutyrate (BHB) concentration. Subsequently, we collected subcutaneous adipose tissue samples from six healthy and six clinically ketotic Holstein cows at 17 ± 4 days postpartum. Commercial kits were used to test the abundance of BHB, non-esterified fatty acid (NEFA), the liver function index (LFI), interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α). We found that cows with clinical ketosis exhibited higher levels of BHB, NEFA, LFI, IL-6, IL-1β, TNF-α, and lower glucose levels than healthy cows. Furthermore, the abundance of CaM, toll-like receptor 4 (TLR4), inhibitor of nuclear factor κB kinase subunit β (IKK), phosphorylated nuclear factor κB p65/nuclear factor κB p65 (p-NF-κB p65/NF-κB p65), adipose triacylglycerol lipase (ATGL), and phosphorylated hormone-sensitive lipase/hormone-sensitive lipase (p-HSL/HSL) was increased, while that of perilipin-1 (PLIN1) was decreased in the adipose tissue of cows with clinical ketosis. To investigate the mechanism underlying the responses, we isolated the primary bovine adipocytes from the adipose tissue of healthy cows and induced the inflammatory response mediated by TLR4/IKK/NF-κB p65 with lipopolysaccharide (LPS). Additionally, we treated the primary bovine adipocytes with CaM overexpression adenovirus and CaM small interfering RNA. In vitro, LPS upregulated the abundance of TLR4, IKK, p-NF-κB p65, ATGL, p-HSL/HSL, and CaM and downregulated PLIN1. Furthermore, CaM silencing downregulated the abundance of LPS-activated p-HSL/HSL, TLR4, IKK, and p-NF-κB p65 and upregulated PLIN1 in bovine adipocytes, except for ATGL. However, CaM overexpression upregulated the abundance of LPS-activated p-HSL/HSL, TLR4, IKK, and p-NF-κB p65 and downregulated PLIN1 expression in bovine adipocytes. These data suggest that CaM promotes lipolysis in adipocytes through HSL and PINL1 while activating the TLR4/IKK/NF-κB inflammatory pathway to stimulate an inflammatory response. There is a positive feedback loop between CaM, lipolysis, and inflammation. Inhibiting CaM may act as an adaptive mechanism to alleviate metabolic dysregulation in adipose tissue, thereby relieving lipolysis and inflammatory responses. Full article