Induction of adipogenic differentiation in three-dimensional culture model on a novel microfabricated scaffold

Development of in vitro three-dimensional co-culture system for metabolic syndrome therapeutic agents

AIMS

There are many obstacles to overcome in the development of new drugs for metabolic diseases, including efficacy and toxicity problems in later stages of drug development. To overcome these problems and predict efficacy and toxicity in early stages, we constructed a new model of insulin resistance in terms of communication between 3T3-L1 adipocytes and RAW264.7 macrophages by three-dimensional (3D) culture.

RESULTS

In this study, results focused on the functional resemblance between 3D co-culture of adipocytes and macrophages and adipose tissue in diabetic mice. The 3D mono-culture preadipocytes showed good cell viability and induced cell differentiation to adipocytes, without cell confluence or cell-cell contact and interaction. The 3D co-cultured preadipocytes with RAW264.7 macrophages induced greater insulin resistance than two-dimensional and 3D mono-cultured adipocytes. Additionally, we demonstrated that 3D co-culture model had functional metabolic similarity to adipose tissue in diabetic mice. We utilized this 3D co-culture system to screen PPARγ antagonists that might have potential as therapeutic agents for diabetes as demonstrated by an in vivo assay.

CONCLUSION

This in vitro 3D co-culture system could serve as a next-generation platform to accelerate the development of therapeutics for metabolic diseases.

Cancer cell spheroids for screening of chemotherapeutics and drug-delivery systems

Over the last few decades, the most popular platform to perform high-throughput screening for viable anti-neoplastic compounds has been monolayer cell culture. However, cells in monolayer culture lose many of their in vivo characteristics. As a result, this platform provides a limited predictive value in determining the clinical outcome of the compounds of interest. Using a technique known as 3D spheroid culture, may be the answer to this conundrum. Spheroids have been shown to mimic the tissue-like properties of tumors necessary for the proper evaluation of compounds. In this review, production of cancer cell spheroids, utilization of these spheroids in understanding various therapeutic mechanisms and the potential for their use in high-throughput screening of drugs and drug-delivery systems are discussed in detail.

Opportunities and challenges in three-dimensional brown adipogenesis of stem cells

The formation of brown adipose tissue (BAT) via brown adipogenesis has become a notable process due to its ability to expend energy as heat with implications in the treatment of metabolic disorders and obesity. With the advent of complexity within white adipose tissue (WAT) along with inducible brown adipocytes (also known as brite and beige), there has been a surge in deciphering adipocyte biology as well as in vivo adipogenic microenvironments. A therapeutic outcome would benefit from understanding early events in brown adipogenesis, which can be accomplished by studying cellular differentiation. Pluripotent stem cells are an efficient model for differentiation and have been directed towards both white adipogenic and brown adipogenic lineages. The stem cell microenvironment greatly contributes to terminal cell fate and as such, has been mimicked extensively by various polymers including those that can form 3D hydrogel constructs capable of biochemical and/or mechanical modifications and modulations. Using bioengineering approaches towards the creation of 3D cell culture arrangements is more beneficial than traditional 2D culture in that it better recapitulates the native tissue biochemically and biomechanically. In addition, such an approach could potentially protect the tissue formed from necrosis and allow for more efficient implantation. In this review, we highlight the promise of brown adipocytes with a focus on brown adipogenic differentiation of stem cells using bioengineering approaches, along with potential challenges and opportunities that arise when considering the energy expenditure of BAT for prospective therapeutics.