Regulatory Effects of Metformin, an Antidiabetic Biguanide Drug, on the Metabolism of Primary Rat Adipocytes

Gestational Caloric Restriction Alters Adipose Tissue Methylome and Offspring's Metabolic Profile in a Swine Model

Limited nutrient supply to the fetus results in physiologic and metabolic adaptations that have unfavorable consequences in the offspring. In a swine animal model, we aimed to study the effects of gestational caloric restriction and early postnatal metformin administration on offspring's adipose tissue epigenetics and their association with morphometric and metabolic variables. Sows were either underfed (30% restriction of total food) or kept under standard diet during gestation, and piglets were randomly assigned at birth to receive metformin (n = 16 per group) or vehicle treatment (n = 16 per group) throughout lactation. DNA methylation and gene expression were assessed in the retroperitoneal adipose tissue of piglets at weaning. Results showed that gestational caloric restriction had a negative effect on the metabolic profile of the piglets, increased the expression of inflammatory markers in the adipose tissue, and changed the methylation of several genes related to metabolism. Metformin treatment resulted in positive changes in the adipocyte morphology and regulated the methylation of several genes related to atherosclerosis, insulin, and fatty acids signaling pathways. The methylation and gene expression of the differentially methylated FASN, SLC5A10, COL5A1, and PRKCZ genes in adipose tissue associated with the metabolic profile in the piglets born to underfed sows. In conclusion, our swine model showed that caloric restriction during pregnancy was associated with impaired inflammatory and DNA methylation markers in the offspring's adipose tissue that could predispose the offspring to later metabolic abnormalities. Early metformin administration could modulate the size of adipocytes and the DNA methylation changes.

The Anti-Diabetic Potential of Baicalin: Evidence from Rodent Studies

Baicalin is a biologically active flavonoid compound that benefits the organism in various pathological conditions. Rodent studies have shown that this compound effectively alleviates diabetes-related disturbances in models of type 1 and type 2 diabetes. Baicalin supplementation limited hyperglycemia and improved insulin sensitivity. The anti-diabetic effects of baicalin covered the main insulin-sensitive tissues, i.e., the skeletal muscle, the adipose tissue, and the liver. In the muscle tissue, baicalin limited lipid accumulation and improved glucose transport. Baicalin therapy was associated with diminished adipose tissue content and increased mitochondrial biogenesis. Hepatic lipid accumulation and glucose output were also decreased as a result of baicalin supplementation. The molecular mechanism of the anti-diabetic action of this compound is pleiotropic and is associated with changes in the expression/action of pivotal enzymes and signaling molecules. Baicalin positively affected, among others, the tissue insulin receptor, glucose transporter, AMP-activated protein kinase, protein kinase B, carnitine palmitoyltransferase, acetyl-CoA carboxylase, and fatty acid synthase. Moreover, this compound ameliorated diabetes-related oxidative and inflammatory stress and reduced epigenetic modifications. Importantly, baicalin supplementation at the effective doses did not induce any side effects. Results of rodent studies imply that baicalin may be tested as an anti-diabetic agent in humans.

Chitosan Derivative-Based Microspheres Loaded with Fibroblast Growth Factor for the Treatment of Diabetes

Diabetes mellitus type 2 (T2DM) is a disease caused by genetic and environmental factors, and the main clinical manifestation is hyperglycemia. Currently, insulin injections are still the first-line treatment for diabetes. However, repeated injections may cause insulin resistance, hypoglycemia, and other serious side effects. Thus, it is imperative to develop new diabetes treatments. Protein-based diabetes drugs, such as fibroblast growth factor-21 (FGF-21), have a longer-lasting glycemic modulating effect with high biosafety. However, the instability of these protein drugs limits their applications. In this study, we extract protein hypoglycemic drugs with oral and injectable functions. The FGF-21 analog (NA-FGF) was loaded into the chitosan derivative-based nanomaterials, N-2-Hydroxypropyl trimethyl ammonium chloride chitosan/carboxymethyl chitosan (N-2-HACC/CMCS), to prepare NA-FGF-loaded N-2-HACC/CMCS microspheres (NA-FGF-N-2-HACC/CMCS MPs). It was well demonstrated that NA-FGF-N-2-HACC/CMCS MPs have great biocompatibility, biostability, and durable drug-release ability. In addition to injectable drug delivery, our prepared microspheres were highly advantageous for oral administration. The in vitro and in vivo experimental results suggested that NA-FGF-N-2-HACC/CMCS MPs could be used as a promising candidate and universal nano-delivery system for both oral and injectable hypoglycemic regulation.