Histone deacetylase 3 is an epigenomic brake in macrophage alternative activation.

Macrophages, a key cellular component of inflammation, become functionally polarized in a signal- and context-specific manner. Th2 cytokines such as interleukin 4 (IL-4) polarize macrophages to a state of alternative activation that limits inflammation and promotes wound healing. Alternative activation is mediated by a transcriptional program that is influenced by epigenomic modifications, including histone acetylation. Here we report that macrophages lacking histone deacetylase 3 (HDAC3) display a polarization phenotype similar to IL-4-induced alternative activation and, furthermore, are hyperresponsive to IL-4 stimulation. Throughout the macrophage genome, HDAC3 deacetylates histone tails at regulatory regions, leading to repression of many IL-4-regulated genes characteristic of alternative activation. Following exposure to Schistosoma mansoni eggs, a model of Th2 cytokine-mediated disease that is limited by alternative activation, pulmonary inflammation was ameliorated in mice lacking HDAC3 in macrophages. Thus, HDAC3 functions in alternative activation as a brake whose release could be of benefit in the treatment of multiple inflammatory diseases.

Buckman extended: federal preemption of state fraud-on-the-FDA statutes.

A number of states have enacted statutes that provide protection to drug manufacturers in product liability actions. Additionally, several of these states have enacted "fraud-on-the-FDA" statutory provisions, which remove statutory protection afforded to drug manufacturers in product liability actions if plaintiffs can provide evidence that the drug manufacturer made misrepresentations to the FDA during the process of obtaining marketing approval for the drug. Currently, the federal circuits are in disagreement over whether these state "fraud-on-the-FDA" statutes should be federally preempted. This issue warrants resolution for drug manufacturers, private citizens, and state legislatures. This Comment will discuss the history and role of the FDA's authority in drug and medical device regulation; federal preemption generally and the Supreme Court's decisions that considered whether state law failure to warn claims are federally preempted in the context of drugs and medical devices; the Supreme Court's decision in Buckman v. Plaintiffs' Legal Committee, where the Court held that claims that a medical device manufacturer made fraudulent representations to the FDA were federally preempted because such claims interfered with the relationship between the FDA and the entities it regulated, state fraud-on-the-FDA statutory provisions, and the existing circuit split regarding whether those statutes should be federally preempted; the potential resolutions to the circuit split; and will conclude and advocate that the Supreme Court's Buckman holding be applied to federally preempt state fraud-on-the-FDA statutes because such statutes involve the relationship between a federal agency and the entity it regulates and thus undermine the FDA's authority.

A novel adipose-specific gene deletion model demonstrates potential pitfalls of existing methods.

Adipose-specific gene deletion in mice is crucial in determining gene function in adipocyte homeostasis and the development of obesity. We noted 100% mortality when the Hdac3 gene was conditionally deleted using Fabp4-Cre mice, the most commonly used model of adipose-targeted Cre recombinase. However, this surprising result was not reproduced using other models of adipose targeting of Cre, including a novel Retn-Cre mouse. These findings underscore the need for caution when interpreting data obtained using Fabp4-Cre mice and should encourage the use of additional or alternative adipose-targeting Cre mouse models before drawing conclusions about in vivo adipocyte-specific functions.