In vitro micro-physiological model of the inflamed human adipose tissue for immune-metabolic analysis in type II diabetes

Background/Aims: Impaired adipogenesis may be the underlying cause in the development of obesity and type II diabetes. Mechanistically, the family of Homeobox transcription factors is implicated in the regulation of adipocyte fate. Hoxa5 is highly expressed in adipocytes, and its mRNA expression is decreased during differentiation. However, the function of Hoxa5 in adipose tissue has been poorly understood. The aim of this study is to unveil the role of Hoxa5 on adipocyte differentiation and its underlying mechanisms. Methods: Quantitative real-time PCR (qPCR) and western blot were performed to determine Hoxa5 expression in primary adipocytes and in adipose tissues from mice. Lipid accumulation was evaluated by bodipy staining. Dual luciferase assay was applied to explore the transcription factor of Hoxa5 and the transcriptional target gene modulated by Hoxa5. All measurements were performed at least for three times at least. Results: A significant reduction of Hoxa5 expression was observed in adipose tissue of High Fat Diet (HFD) induced obesity mice. We determined Hoxa5 increased adipocytes differentiation and mitochondrial biogenesis in adipocytes in vitro. CEBPβ was determined a transcription factor of Hoxa5 and inhibited methylation level of Hoxa5 by combining on the promoter of Hoxa5. Importantly, we found Fabp4, a known positive regulator of adipocytes differentiation, was transcriptional activation by Hoxa5. In addition, Hoxa5 promotes adipocytes differentiation by inhibiting PKA/HSL pathway. Conclusion: Our study demonstrated the promoting role of Hoxa5 in adipocytes differentiation and therefore bringing a new therapeutic mean to the treatment of obesity and type II diabetes.

Download Full-text

The effect of Milgamma NR and SperminR on in vitro cellular immune reactions in patients with type II diabetes mellitus

Immunology Letters ◽

10.1016/s0165-2478(97)88807-4 ◽

1997 ◽

Vol 56 (1-3) ◽

pp. 482

Author(s):

M Horváth

Keyword(s):

Diabetes Mellitus ◽

Type Ii Diabetes ◽

Type Ii Diabetes Mellitus ◽

Type Ii ◽

Immune Reactions ◽

Cellular Immune

Download Full-text

IN VITRO STUDIES ON LIPOLYSIS IN HUMAN ADIPOSE TISSUE

Acta Endocrinologica ◽

10.1530/acta.0.061s156 ◽

1969 ◽

Vol 61 (1_Suppl) ◽

pp. S156

Author(s):

Suad Efendić ◽

Peter Amer ◽

Jan Östman

Keyword(s):

Adipose Tissue ◽

Human Adipose Tissue ◽

In Vitro Studies

Download Full-text

Long-Term Severe In Vitro Hypoxia Exposure Enhances the Vascularization Potential of Human Adipose Tissue-Derived Stromal Vascular Fraction Cell Engineered Tissues

International Journal of Molecular Sciences ◽

10.3390/ijms22157920 ◽

2021 ◽

Vol 22 (15) ◽

pp. 7920

Author(s):

Myroslava Mytsyk ◽

Giulia Cerino ◽

Gregory Reid ◽

Laia Gili Sole ◽

Friedrich S. Eckstein ◽

...

Keyword(s):

Adipose Tissue ◽

Therapeutic Potential ◽

Stromal Vascular Fraction ◽

Human Adipose Tissue ◽

Bioreactor Culture ◽

Proliferating Cells ◽

Angiogenic Potential ◽

Engineered Tissues

The therapeutic potential of mesenchymal stromal/stem cells (MSC) for treating cardiac ischemia strongly depends on their paracrine-mediated effects and their engraftment capacity in a hostile environment such as the infarcted myocardium. Adipose tissue-derived stromal vascular fraction (SVF) cells are a mixed population composed mainly of MSC and vascular cells, well known for their high angiogenic potential. A previous study showed that the angiogenic potential of SVF cells was further increased following their in vitro organization in an engineered tissue (patch) after perfusion-based bioreactor culture. This study aimed to investigate the possible changes in the cellular SVF composition, in vivo angiogenic potential, as well as engraftment capability upon in vitro culture in harsh hypoxia conditions. This mimics the possible delayed vascularization of the patch upon implantation in a low perfused myocardium. To this purpose, human SVF cells were seeded on a collagen sponge, cultured for 5 days in a perfusion-based bioreactor under normoxia or hypoxia (21% and <1% of oxygen tension, respectively) and subcutaneously implanted in nude rats for 3 and 28 days. Compared to ambient condition culture, hypoxic tension did not alter the SVF composition in vitro, showing similar numbers of MSC as well as endothelial and mural cells. Nevertheless, in vitro hypoxic culture significantly increased the release of vascular endothelial growth factor (p < 0.001) and the number of proliferating cells (p < 0.00001). Moreover, compared to ambient oxygen culture, exposure to hypoxia significantly enhanced the vessel length density in the engineered tissues following 28 days of implantation. The number of human cells and human proliferating cells in hypoxia-cultured constructs was also significantly increased after 3 and 28 days in vivo, compared to normoxia. These findings show that a possible in vivo delay in oxygen supply might not impair the vascularization potential of SVF- patches, which qualifies them for evaluation in a myocardial ischemia model.

Download Full-text

Signal Transducer and Activator of Transcription 3 (STAT3) Suppresses STAT1/Interferon Signaling Pathway and Inflammation in Senescent Preadipocytes

Antioxidants ◽

10.3390/antiox10020334 ◽

2021 ◽

Vol 10 (2) ◽

pp. 334

Author(s):

Aisha Y. Madani ◽

Yasser Majeed ◽

Houari B. Abdesselem ◽

Maha V. Agha ◽

Muneera Vakayil ◽

...

Keyword(s):

Adipose Tissue ◽

Molecular Mechanisms ◽

Adenosine Monophosphate ◽

Human Adipose Tissue ◽

Premature Aging ◽

Guanosine Monophosphate ◽

Negative Regulator ◽

Signal Transducer ◽

Interferon Signaling

Obesity promotes premature aging and dysfunction of white adipose tissue (WAT) through the accumulation of cellular senescence. The senescent cells burden in WAT has been linked to inflammation, insulin-resistance (IR), and type 2 diabetes (T2D). There is limited knowledge about molecular mechanisms that sustain inflammation in obese states. Here, we describe a robust and physiologically relevant in vitro system to trigger senescence in mouse 3T3-L1 preadipocytes. By employing transcriptomics analyses, we discovered up-regulation of key pro-inflammatory molecules and activation of interferon/signal transducer and activator of transcription (STAT)1/3 signaling in senescent preadipocytes, and expression of downstream targets was induced in epididymal WAT of obese mice, and obese human adipose tissue. To test the relevance of STAT1/3 signaling to preadipocyte senescence, we used Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR associated protein 9 (CRISPR/Cas9) technology to delete STAT1/3 and discovered that STAT1 promoted growth arrest and cooperated with cyclic Guanosine Monophosphate-Adenosine Monophosphate (GMP-AMP) synthase-stimulator of interferon genes (cGAS-STING) to drive the expression of interferon β (IFNβ), C-X-C motif chemokine ligand 10 (CXCL10), and interferon signaling-related genes. In contrast, we discovered that STAT3 was a negative regulator of STAT1/cGAS-STING signaling—it suppressed senescence and inflammation. These data provide insights into how STAT1/STAT3 signaling coordinates senescence and inflammation through functional interactions with the cGAS/STING pathway.

Download Full-text