scholarly journals Adipose MDM2 regulates systemic insulin sensitivity

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Philip Hallenborg ◽  
Benjamin Anderschou Holbech Jensen ◽  
Even Fjære ◽  
Rasmus Koefoed Petersen ◽  
Mohammed-Samir Belmaâti ◽  
...  

AbstractThe intimate association between obesity and type II diabetes urges for a deeper understanding of adipocyte function. We and others have previously delineated a role for the tumor suppressor p53 in adipocyte biology. Here, we show that mice haploinsufficient for MDM2, a key regulator of p53, in their adipose stores suffer from overt obesity, glucose intolerance, and hepatic steatosis. These mice had decreased levels of circulating palmitoleic acid [non-esterified fatty acid (NEFA) 16:1] concomitant with impaired visceral adipose tissue expression of Scd1 and Ffar4. A similar decrease in Scd and Ffar4 expression was found in in vitro differentiated adipocytes with perturbed MDM2 expression. Lowered MDM2 levels led to nuclear exclusion of the transcriptional cofactors, MORC2 and LIPIN1, and thereby possibly hampered adipocyte function by antagonizing LIPIN1-mediated PPARγ coactivation. Collectively, these data argue for a hitherto unknown interplay between MDM2 and MORC2/LIPIN1 involved in balancing adipocyte function.

Antioxidants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1210
Author(s):  
Amy K. Hauck ◽  
Tong Zhou ◽  
Ambuj Upadhyay ◽  
Yuxiang Sun ◽  
Michael B. O’Connor ◽  
...  

Oxidative stress is a hallmark of metabolic disease, though the mechanisms that define this link are not fully understood. Irreversible modification of proteins by reactive lipid aldehydes (protein carbonylation) is a major consequence of oxidative stress in adipose tissue and the substrates and specificity of this modification are largely unexplored. Here we show that histones are avidly modified by 4-hydroxynonenal (4-HNE) in vitro and in vivo. Carbonylation of histones by 4-HNE increased with age in male flies and visceral fat depots of mice and was potentiated in genetic (ob/ob) and high-fat feeding models of obesity. Proteomic evaluation of in vitro 4-HNE- modified histones led to the identification of both Michael and Schiff base adducts. In contrast, mapping of sites in vivo from obese mice exclusively revealed Michael adducts. In total, we identified 11 sites of 4-hydroxy hexenal (4-HHE) and 10 sites of 4-HNE histone modification in visceral adipose tissue. In summary, these results characterize adipose histone carbonylation as a redox-linked epigenomic mark associated with metabolic disease and aging.


2015 ◽  
Vol 42 (7) ◽  
pp. 1042-1049 ◽  
Author(s):  
Yu Zhang ◽  
Ying Zhong ◽  
Mei Hu ◽  
Nanxi Xiang ◽  
Yao Fu ◽  
...  

2018 ◽  
Vol 12 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Antônio Sérgio Barcala Jorge ◽  
João Marcus Oliveira Andrade ◽  
Alanna Fernandes Paraíso ◽  
Gislaine Candida Batista Jorge ◽  
Christine Mendes Silveira ◽  
...  

Author(s):  
Mayuri B. Patil ◽  
Avish D. Maru ◽  
Jayshree S. Bhadane

The aim of the present study was to design and evaluate bilayer tablets of metformin hydrochloride as sustained release form for the treatment of Type-II diabetes mellitus. The basic aim of any Bi-layer tablet formulation is to separate physically or chemically incompatible ingredients and to produce repeat action or prolonged action of tablet. They are many drugs for treating type-II diabetes. Sulphonyl urea and biguanides are used commonly by a wide section of patients. Melt granulation process was used for the formulation of sustained comprising metformin layer and wet granulation of immediate comprising layer of glimepiride. The precompression studies like bulk density, tapped density, angle of repose, compressible index and post formulation studies includes weight variation, hardness, thickness, friability and dissolution study. The in-vitro release profile of Glimepiride was dissolved within 45 min, and Metformin Hydrochloride was able to release more than 12 hrs. They all the formulation was optimized formula due to its higher rate of dissolution and collate all other parameters with the official specifications.


2011 ◽  
Vol 2011 ◽  
pp. 1-18
Author(s):  
Richard A. Zuellig ◽  
Beat C. Bornhauser ◽  
Ralf Amstutz ◽  
Bruno Constantin ◽  
Marcus C. Schaub

Utrophin and dystrophin present two large proteins that link the intracellular actin cytoskeleton to the extracellular matrix via the C-terminal-associated protein complex. Here we describe a novel short N-terminal isoform of utrophin and its protein product in various rat tissues (N-utro, 62 kDa, amino acids 1–539, comprising the actin-binding domain plus the first two spectrin repeats). Using different N-terminal recombinant utrophin fragments, we show that actin binding exhibits pronounced negative cooperativity (affinity constantsK1=∼5×106andK2=∼1×105 M-1) and is Ca2+-insensitive. Expression of the different fragments in COS7 cells and in myotubes indicates that the actin-binding domain alone binds exlusively to actin filaments. The recombinant N-utro analogue binds in vitro to actin and in the cells associates to the membranes. The results indicate that N-utro may be responsible for the anchoring of the cortical actin cytoskeleton to the membranes in muscle and other tissues.


Author(s):  
Jirawat Riyaphan ◽  
Chien-Hung Jhong ◽  
May-Jwan Tsai ◽  
Der-Nan Lee ◽  
Max K. Leong ◽  
...  

The inhibition of alpha-glucosidase and alpha-amylase is one of clinic strategies for remedy the type II diabetes. Herbal medicines are reported to alleviate hyperglycemia. However, the constituents from those sources whether are targeted to the alpha-glucosidase and alpha-amylase still unexplored. This study attempted to select the compounds for efficacy of hypoglycemia via cellular and mouse levels. The results illustrated that the cytotoxicity in all tested compounds at various concentrations except the concentration of 16-hydroxy-cleroda-3,13-dine-16,15-olide (HCD) at 30 µM were not significant difference (p > 0.05) when compared with the untreated control. Acarbose (reference drug), Antroquinonol, Catechin, Quercetin, Actinodaphnine, Curcumin, HCD, Docosanol, Tetracosanol, Berberine, and Rutin could effectively inhibit the alpha-glucosidase activity of Caco-2 cells when compared with the control (maltose). The compounds (Curcumin, HCD, Tetracosanol, Antroquinonol, Berberine, Catechin, Actinodaphnine, and Rutin) could reduce blood sugar level at 30 min in tested mice. The effects of tested compounds on area under curve (AUC) were significant (p < 0.05) among Acarbose, Tetracosanol, Antroquinonol, Catechin, Actinodaphnine, and Rutin along with Berberine and Quercetin. In in vitro (alpha-glucosidase) with in vivo (alpha-amylase) experiments suggest that bioactive compounds can be a potential inhibitor candidate of alpha-glucosidase and alpha-amylase for the alleviation of type II diabetes.


2020 ◽  
Vol 21 (3) ◽  
Author(s):  
Małgorzata Kania-Dobrowolska ◽  
Justyna Baraniak ◽  
Aleksandra Górska ◽  
Marlena Wolek ◽  
Anna Bogacz

Atherosclerosis and type II diabetes can be classified as lifestyle diseases. Unbalanced diet (highly processed food, excess salt food), a sedentary lifestyle and the use of stimulants (cigarettes, alcohol) can contribute to the emergence of both diseases. Both these diseases can coexist simultaneously. The development of type 2 diabetes may accelerate the development of atherosclerotic plaque, which in turn leads to many organ complications as well as death. People with slightly elevated glucose and cholesterol levels can be advised to take natural plant ingredients such as garlic and ginger along with changing their diet and increasing physical activity. garlic and ginger can be consumed alone as well as an addition to many dishes. In vitro and in vivo and clinical tests indicate the possibility of supporting the regulation of blood glucose and cholesterol levels by adding garlic and ginger to the diet.


2016 ◽  
Vol 62 (5) ◽  
pp. 45-46
Author(s):  
Paulina Ormazabal ◽  
Beatrice Scazzocchio ◽  
Rosaria Varì ◽  
Annunziata Iacovelli ◽  
Roberta Masella

Adipocytes exposed to high glucose concentrations exhibit impaired insulin signaling. Binding of insulin to its membrane receptor activates insulin metabolic pathway leading to IRS-1 and AKT phosphorylations. The accumulation of visceral adipose tissue (VAT) correlates with insulin resistance and metabolic syndrome. Anthocyanins (ACN) are bioactive food compounds of great nutritional interest. We have shown that protocatechuic acid (PCA), a major metabolite of ACN, might exert insulin-sensitizer activities in human visceral adipose tissue. The aim of this work was to define the protective role of PCA against insulin-resistance induced by high glucose in VAT.Methodology: VAT obtained from control subject (BMI≤25) were separated in four experimental groups: i) PCA: samples treated for 24 h with 100 μM PCA, ii) GLU: VAT treated with 30 mM glucose for 24 h, iii) PCA+GLU: 1 hour incubation with 100 μM PCA before adding glucose (30 mM, 24 h), iv) CTR: vehicle. After treatment, VAT groups were (or not) acutely stimulated with insulin (20 nM, 20 min). Tyr-IRS-1 and Ser-Akt phosphorylations were assessed by Western blotting (WB) in basal or insulin stimulated tissues in all experimental groups. Samples were assessed for IRS-1, IR, Akt and GLUT4 protein content by WB. Results: No differences in protein contents between experimental groups were found. GLU tissues showed a lower increment in insulin-stimulated phosphorylation of IRS-1 and Akt compared to CTR and PCA samples. This impaired activation was completely reversed by the pretreatment with PCA.Conclusion: An in-vitro insulin-resistance condition induced by high glucose was established in biopsies of VAT. PCA restores the ability of GLU-tissues to fully respond to insulin by increasing IRS-1 and Akt phosphorylations. These results confirm the insulin-sensitizer effect of PCA on VAT previously reported by our group. An anthocyanin rich diet might help to protect against insulin-resistance in VAT.


1978 ◽  
Vol 31 (1) ◽  
pp. 199-211
Author(s):  
N.B. Berg

The types of sulphated macromolecules produced by the exocrine pancrease were investigated. To determine whether this tissue utilized inorganic sulphate for protein production, the in-vitro behaviour of material labelled with 35S-sulphate was compared with material labelled with [3H]leucine (secretory proteins). While incubating tissue slices in the presence of cycloheximide resulted in an immediate and nearly complete inhibition of protein synthesis, a similar decrease in production of sulphated material was not observed until after 2 h of incubation in the presence of the drug. Likewise, the kinetics of pilocarpine-induced discharge of radioactive material from pancreatic slices pulse-labelled with either 3H-Leu. or 35S-sulphate was compared. During the first 90 min of stimulation sulphated macromolecules were detected in chase medium 10–15 min prior to the appearance of 3H-labelled secretory proteins. That in-vitro behaviour of sulphated material differed from radioleucine-labelled material is indicative of the fact that the pancreas utilizes inorganic sulphate for the production of macromolecules other than secretory proteins. Lipid and proteoglycan fractions were prepared from pancreatic tissue 4 h after intraperitoneal injection of radiosulphate. The recovery of a significant amount of radioactivity in both fractions deomonstrated the ability of the pancreas to use inorganic sulphate for the production of both sulphated lipids and sulphated proteoglycans. The possible function of sulphated macromolecules in pancreatic secretion is discussed.


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