-
Current Issues in Molecular Biology May 2024Hyperlipidemia is a prevalent chronic metabolic disease that severely affects human health. Currently, commonly used clinical therapeutic drugs are prone to drug...
Identification of Key Hypolipidemic Components and Exploration of the Potential Mechanism of Total Flavonoids from Based on Network Pharmacology, Molecular Docking, and Zebrafish Experiment.
Hyperlipidemia is a prevalent chronic metabolic disease that severely affects human health. Currently, commonly used clinical therapeutic drugs are prone to drug dependence and toxic side effects. Dietary intervention for treating chronic metabolic diseases has received widespread attention. is a characteristic fruit tree in China whose fruits are rich in flavonoids, which have been shown to have a therapeutic effect on hyperlipidemia; however, their exact molecular mechanism of action remains unclear. Therefore, this study aimed to investigate the therapeutic effects of total flavonoid extract (RS) on hyperlipidemia and its possible mechanisms. A hyperlipidemic zebrafish model was established using egg yolk powder and then treated with RS to observe changes in the integral optical density in the tail vessels. Network pharmacology and molecular docking were used to investigate the potential mechanism of action of RS for the treatment of hyperlipidemia. The results showed that RS exhibited favorable hypolipidemic effects on zebrafish in the concentration range of 3.0-30.0 μg/mL in a dose-dependent manner. Topological and molecular docking analyses identified HSP90AA1, PPARA, and MMP9 as key targets for hypolipidemic effects, which were exerted mainly through lipolytic regulation of adipocytes and lipids; pathway analysis revealed enrichment in atherosclerosis, chemical carcinogenic-receptor activation pathways in cancers, and proteoglycans in prostate cancer and other cancers. Mover, chinensinaphthol possessed higher content and better target binding ability, which suggested that chinensinaphthol might be an important component of RS with hypolipidemic active function. These findings provide a direction for further research on RS interventions for the treatment of hyperlipidemia.
PubMed: 38920980
DOI: 10.3390/cimb46060308 -
Cells Jun 2024: Despite its increasing incidence and prevalence throughout Western countries, lipedema continues to be a very enigmatic disease, often misunderstood or misdiagnosed by...
: Despite its increasing incidence and prevalence throughout Western countries, lipedema continues to be a very enigmatic disease, often misunderstood or misdiagnosed by the medical community and with an intrinsic pathology that is difficult to trace. The nature of lipedemic tissue is one of hypertrophic adipocytes and poor tissue turnover. So far, there are no identified pathways responsible, and little is known about the cell populations of lipedemic fat. : Adipose tissue samples were collected from affected areas of both lipedema and healthy participants. For single-cell RNA sequencing analysis, the samples were dissociated into single-cell suspensions using enzymatic digestion and then encapsulated into nanoliter-sized droplets containing barcoded beads. Within each droplet, cellular mRNA was converted into complementary DNA. Complementary DNA molecules were then amplified for downstream analysis. : The single-cell RNA-sequencing analysis revealed three distinct adipocyte populations at play in lipedema. These populations have unique gene signatures which can be characterized as a lipid generating adipocyte, a disease catalyst adipocyte, and a lipedemic adipocyte. : The single-cell RNA sequencing of lipedemic tissue samples highlights a triad of distinct adipocyte subpopulations, each characterized by unique gene signatures and functional roles. The interplay between these adipocyte subtypes offers promising insights into the complex pathophysiology of lipedema.
Topics: Humans; Adipocytes; Single-Cell Analysis; Lipedema; Sequence Analysis, RNA; Female; Male; Adult; Middle Aged; Adipose Tissue
PubMed: 38920656
DOI: 10.3390/cells13121028 -
Cells Jun 2024Mesenchymal stem cells (MSCs) of placental origin hold great promise in tissue engineering and regenerative medicine for diseases affecting cartilage and bone. However,...
Mesenchymal stem cells (MSCs) of placental origin hold great promise in tissue engineering and regenerative medicine for diseases affecting cartilage and bone. However, their utility has been limited by their tendency to undergo premature senescence and phenotypic drift into adipocytes. This study aimed to explore the potential involvement of a specific subset of aging and antiaging genes by measuring their expression prior to and following in vitro-induced differentiation of placental MSCs into chondrocytes and osteoblasts as opposed to adipocytes. The targeted genes of interest included the various transcript variants (lamin A, lamin C, and lamin A∆10), sirtuin 7 (SIRT7), and SM22α, along with the classic aging markers plasminogen activator inhibitor 1 (PAI-1), p53, and p16. MSCs were isolated from the decidua basalis of human term placentas, expanded, and then analyzed for phenotypic properties by flow cytometry and evaluated for colony-forming efficiency. The cells were then induced to differentiate in vitro into chondrocytes, osteocytes, and adipocytes following established protocols. The mRNA expression of the targeted genes was measured by RT-qPCR in the undifferentiated cells and those fully differentiated into the three cellular lineages. Compared to undifferentiated cells, the differentiated chondrocytes demonstrated decreased expression of SIRT7, along with decreased PAI-1, lamin A, and SM22α expression, but the expression of p16 and p53 increased, suggesting their tendency to undergo premature senescence. Interestingly, the cells maintained the expression of lamin C, which indicates that it is the primary lamin variant influencing the mechanoelastic properties of the differentiated cells. Notably, the expression of all targeted genes did not differ from the undifferentiated cells following osteogenic differentiation. On the other hand, the differentiation of the cells into adipocytes was associated with decreased expression of lamin A and PAI-1. The distinct patterns of expression of aging and antiaging genes following in vitro-induced differentiation of MSCs into chondrocytes, osteocytes, and adipocytes potentially reflect specific roles for these genes during and following differentiation in the fully functional cells. Understanding these roles and the network of signaling molecules involved can open opportunities to improve the handling and utility of MSCs as cellular precursors for the treatment of cartilage and bone diseases.
Topics: Humans; Mesenchymal Stem Cells; Female; Placenta; Cell Differentiation; Chondrogenesis; Pregnancy; Osteogenesis; Biomarkers; Cellular Senescence; Chondrocytes; Aging; Lamin Type A
PubMed: 38920652
DOI: 10.3390/cells13121022 -
Nature Communications Jun 2024Adipose tissue macrophages (ATMs) influence obesity-associated metabolic dysfunction, but the mechanisms by which they do so are not well understood. We show that...
Adipose tissue macrophages (ATMs) influence obesity-associated metabolic dysfunction, but the mechanisms by which they do so are not well understood. We show that miR-6236 is a bona fide miRNA that is secreted by ATMs during obesity. Global or myeloid cell-specific deletion of miR-6236 aggravates obesity-associated adipose tissue insulin resistance, hyperglycemia, hyperinsulinemia, and hyperlipidemia. miR-6236 augments adipocyte insulin sensitivity by inhibiting translation of negative regulators of insulin signaling, including PTEN. The human genome harbors a miR-6236 homolog that is highly expressed in the serum and adipose tissue of obese people. hsa-MIR-6236 expression negatively correlates with hyperglycemia and glucose intolerance, and positively correlates with insulin sensitivity. Together, our findings establish miR-6236 as an ATM-secreted miRNA that potentiates adipocyte insulin signaling and protects against metabolic dysfunction during obesity.
Topics: MicroRNAs; Obesity; Animals; Adipocytes; Hyperglycemia; Humans; Signal Transduction; Insulin; Insulin Resistance; Mice; Male; PTEN Phosphohydrolase; Mice, Inbred C57BL; Macrophages; Adipose Tissue; Myeloid Cells; Mice, Knockout; Hyperinsulinism
PubMed: 38918428
DOI: 10.1038/s41467-024-49632-z -
European Journal of Endocrinology Jun 2024Brown adipose tissue (BAT) is a therapeutic target for obesity. 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is commonly used to quantify human BAT...
OBJECTIVE
Brown adipose tissue (BAT) is a therapeutic target for obesity. 18F-Fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is commonly used to quantify human BAT mass and activity. Detectable 18F-FDG uptake by BAT is associated with reduced prevalence of cardiometabolic disease. However, 18F-FDG uptake may not always be a reliable marker of BAT thermogenesis, for example insulin resistance may reduce glucose uptake. Uncoupling protein 1 (UCP1) is the key thermogenic protein in BAT. Therefore, we hypothesized that UCP1 expression may be altered in individuals with cardiometabolic risk factors.
METHODS
We quantified UCP1 expression as an alternative marker of thermogenic capacity in BAT and white adipose tissue (WAT) samples (n = 53) and in differentiated brown and white pre-adipocytes (n = 85).
RESULTS
UCP1 expression in BAT, but not in WAT or brown/white differentiated pre-adipocytes, was reduced with increasing age, obesity and adverse cardiometabolic risk factors such as fasting glucose, insulin and blood pressure. However, UCP1 expression in BAT was preserved in obese subjects of <40 years of age. To determine if BAT activity was also preserved in vivo, we undertook a case-control study, performing 18F-FDG scanning during mild cold exposure in young (mean age ∼22y) normal weight and obese volunteers. 18F-FDG uptake by BAT and BAT volume were similar between groups, despite increased insulin resistance.
CONCLUSION
18F-FDG uptake by BAT and UCP1 expression are preserved in young obese adults. Older subjects retain precursor cells with the capacity to form new thermogenic adipocytes. These data highlight the therapeutic potential of BAT mass expansion and activation in obesity.
PubMed: 38917410
DOI: 10.1093/ejendo/lvae074 -
Aging and Disease May 2024Type 2 diabetes (T2D) is a widespread health condition both in the United States and around the world, with insulin resistance playing a critical role in its...
Type 2 diabetes (T2D) is a widespread health condition both in the United States and around the world, with insulin resistance playing a critical role in its development. Effective treatment strategies are essential for managing T2D and mitigating associated risks. Adiponectin (APN), secreted by adipocytes, exhibits an inverse correlation with obesity-related adiposity, and its levels are negatively associated with insulin resistance and body mass index. This study aimed to enhance endogenous APN levels in a diet-induced obese (DIO) mouse model using lipid nanoparticles (LNP) as safe delivery agents for APN mRNA conjugates. The results indicate that APN-mRNA-LNP administration successfully induced APN synthesis in various tissues, including muscle, liver, kidney, pancreas, and adipose cells. This induction was associated with several positive outcomes, such as preventing diet-induced body weight gain, improving hyperglycemia by promoting Glut-4 expression, alleviating diabetic nephropathy symptoms by blocking the EGFR pathway, and reducing pro-inflammatory cytokine production. In addition, the treatment demonstrated enhanced insulin sensitivity by activating DGKd and inhibiting PKCε. This resulted in reactivation of insulin receptors in insulin target tissues and stimulation of insulin secretion from pancreatic beta cells. The findings of the present study highlight the potential of APN-mRNA-LNP-based nucleic acid therapy as a treatment for type 2 diabetes, offering a comprehensive approach to addressing its complexities.
PubMed: 38916734
DOI: 10.14336/AD.2024.0162 -
Journal of Mammary Gland Biology and... Jun 2024Conflicting data exist as to how mammary epithelial cell proliferation changes during the reproductive cycle. To study the effect of endogenous hormone fluctuations on...
Conflicting data exist as to how mammary epithelial cell proliferation changes during the reproductive cycle. To study the effect of endogenous hormone fluctuations on gene expression in the mouse mammary gland, we performed bulk RNAseq analyses of epithelial and stromal cell populations that were isolated either during puberty or at different stages of the adult virgin estrous cycle. Our data confirm prior findings that proliferative changes do not occur in every mouse in every cycle. We also show that during the estrous cycle the main gene expression changes occur in adipocytes and fibroblasts. Finally, we present a comprehensive overview of the Wnt gene expression landscape in different mammary gland cell types in pubertal and adult mice. This work contributes to understanding the effects of physiological hormone fluctuations and locally produced signaling molecules on gene expression changes in the mammary gland during the reproductive cycle and should be a useful resource for future studies investigating gene expression patterns in different cell types across different developmental timepoints.
Topics: Animals; Female; Mice; Mammary Glands, Animal; Stromal Cells; Epithelial Cells; Transcriptome; Gene Expression Profiling; Sexual Maturation; Cell Proliferation; Estrous Cycle
PubMed: 38916673
DOI: 10.1007/s10911-024-09565-1 -
Microbiology Spectrum Jun 2024Gut bacteria belonging to the family play a pivotal role in regulating host energy balance and metabolic homeostasis. As a commensal bacterium, has been implicated in...
UNLABELLED
Gut bacteria belonging to the family play a pivotal role in regulating host energy balance and metabolic homeostasis. As a commensal bacterium, has been implicated in modulating host energy homeostasis, albeit the underlying mechanism remains elusive. Therefore, this study aimed to investigate the impact of supplementation on various physiological parameters, intestinal morphology, particularly adipose tissue accumulation, and glucolipid metabolism in mice. The findings reveal that mice supplemented with for 6 weeks exhibited a notable increase in body weight, fat mass, adipocyte size, and serum triglyceride (TG) levels. Notably, the increased fat accumulation is observed despite consistent feed intake in treated mice. Mechanistically, supplementation significantly improved the structure integrity of intestinal villi and enhanced energy absorption efficiency while reducing excretion of carbohydrates and fatty acids in feces. This was accompanied by upregulation of glucose and fatty acid transporter expression. Furthermore, supplementation with promoted adipogenesis in both liver and adipose tissues, as evidenced by increased levels of hepatic pyruvate, acetyl-CoA, and TG, along with elevated expression levels of genes associated with lipid synthesis. Regarding the microbiological aspect, supplementation correlated with an increased abundance of genus bacteria and enhanced carbohydrate enzyme activity. In summary, supplementation significantly promotes fat accumulation in mice by augmenting energy absorption and adipogenesis, possibly mediated by the expansion of bacteria population with robust glycolipid metabolic ability.
IMPORTANCE
The clusters have been implicated in energy metabolism, the specific species and underlying mechanisms remain unclear. This present study is the first to report is able to affect fat accumulation and glycolipid metabolism. We indicated that gavage of promoted the adipogenesis and fat accumulation in mice by not only increasing the abundance of bacteria but by also enhancing the metabolic absorption of carbohydrates and fatty acids significantly. Obviously, changes of gut microbiota caused by the , especially the significant increase of bacteria, contributed to the fat accumulation of mice. In addition, the enhancement of genus bacteria remarkably improved the synthesis of hepatic pyruvate, acetyl-CoA, and triglyceride levels, as well as reduced the excretion of fecal carbohydrates, short-chain fatty acids, and free fatty acids remarkably. These findings will help us to understand the relationship of specific bacteria and host energy homeostasis.
PubMed: 38916334
DOI: 10.1128/spectrum.04116-23 -
BioRxiv : the Preprint Server For... Jun 2024Obesity is a leading risk factor of pancreatic ductal adenocarcinoma (PDAC) that contributes to poor disease prognosis and outcomes. Retrospective studies have...
Obesity is a leading risk factor of pancreatic ductal adenocarcinoma (PDAC) that contributes to poor disease prognosis and outcomes. Retrospective studies have identified this link, but interactions surrounding obesity and PDAC are still unclear. Research has shifted to contributions of fibrosis (desmoplasia) on malignancy, which involves increased deposition of collagens and other extracellular matrix (ECM) molecules and increased ECM crosslinking, all of which contribute to increased tissue stiffening. However, fibrotic stiffening is underrepresented as a model feature in current PDAC models. Fibrosis is shared between PDAC and obesity, and can be leveraged for model design, as current animal obesity models of PDAC are limited in their ability to isolate individual components of fibrosis to study cell behavior. In the current study, methacrylated type I collagen (PhotoCol) was photo-crosslinked to pathological stiffness levels to recapitulate fibrotic ECM stiffening. PANC-1 cells were encapsulated within PhotoCol, and the tumor-tissue constructs were prepared to represent normal (healthy) (~600 Pa) and pathological (~2000 Pa) tissues. Separately, human mesenchymal stem cells were differentiated into adipocytes representing lean (2D differentiation) and obese fat tissue (3D collagen matrix differentiation), and conditioned media was applied to PANC-1 tumor-tissue constructs. Conditioned media from obese adipocytes showed increased vimentin expression, a hallmark of invasiveness and progression, that was not seen after exposure to media from lean adipocytes or control media. Characterization of the obese adipocyte secretome suggested that some PANC-1 differences may arise from increased interleukin-8 and -10 compared to lean adipocytes. Additionally, high matrix stiffness associated induced an amoeboid morphology in PANC-1 cells that was not present at low stiffness. Amoeboid morphology is an accessory to epithelial-to-mesenchymal transition and is used to navigate complex ECM environments. This plasticity has greater implications for treatment efficacy of metastatic cancers. Overall, this work 1) highlights the importance of investigating PDAC-obesity interactions to study the effects on disease progression and persistence, 2) establishes PhotoCol as a matrix material that can be leveraged to study amoeboid morphology and invasion in PDAC, and 3) emphasizes the importance of integrating both biophysical and biochemical interactions associated within both pathologies for PDAC models.
PubMed: 38915620
DOI: 10.1101/2024.06.11.598541 -
Proceedings of the National Academy of... Jul 2024Tibetan sheep were introduced to the Qinghai Tibet plateau roughly 3,000 B.P., making this species a good model for investigating genetic mechanisms of high-altitude...
Tibetan sheep were introduced to the Qinghai Tibet plateau roughly 3,000 B.P., making this species a good model for investigating genetic mechanisms of high-altitude adaptation over a relatively short timescale. Here, we characterize genomic structural variants (SVs) that distinguish Tibetan sheep from closely related, low-altitude Hu sheep, and we examine associated changes in tissue-specific gene expression. We document differentiation between the two sheep breeds in frequencies of SVs associated with genes involved in cardiac function and circulation. In Tibetan sheep, we identified high-frequency SVs in a total of 462 genes, including , , and . Single-cell RNA-Seq data and luciferase reporter assays revealed that the SVs had -acting effects on the expression levels of these three genes in specific tissues and cell types. In Tibetan sheep, we identified a high-frequency chromosomal inversion that exhibited modified chromatin architectures relative to the noninverted allele that predominates in Hu sheep. The inversion harbors several genes with altered expression patterns related to heart protection, brown adipocyte proliferation, angiogenesis, and DNA repair. These findings indicate that SVs represent an important source of genetic variation in gene expression and may have contributed to high-altitude adaptation in Tibetan sheep.
Topics: Animals; Altitude; Sheep; Tibet; Genomic Structural Variation; Basic Helix-Loop-Helix Transcription Factors; Gene Expression Regulation; Genome; Acclimatization
PubMed: 38913905
DOI: 10.1073/pnas.2322291121