The TNFΔARE Mouse as a Model of Intestinal Fibrosis.

Crohn disease (CD) is a highly morbid chronic inflammatory disease. Although many patients with CD also develop fibrostenosing complications, there are no medical therapies for intestinal fibrosis. This is due, in part, to a lack of high-fidelity biomimetic models to enhance understanding and drug development, which highlights the need for developing in vivo models of inflammatory bowel disease-related intestinal fibrosis. This study investigates whether the TNFΔARE mouse, a model of ileal inflammation, also develops intestinal fibrosis. Several clinically relevant outcomes were studied, including features of structural fibrosis, histologic fibrosis, and gene expression. These include the use of a new luminal casting technique, traditional histologic outcomes, use of second harmonic imaging, and quantitative PCR. These features were studied in aged TNFΔARE mice as well as in cohorts of numerous ages. At >24 weeks of age, TNFΔARE mice developed structural, histologic, and transcriptional changes of ileal fibrosis. Protein and RNA expression profiles showed changes as early as 6 weeks, coinciding with histologic changes as early as 14 to 15 weeks. Overt structural fibrosis was delayed until at least 16 weeks and was most developed after 24 weeks. This study found that the TNFΔARE mouse is a viable and highly tractable model of ileal fibrosis. This model and the techniques used herein can be leveraged for both mechanistic studies and therapeutic development for the treatment of intestinal fibrosis.

BODIPY-Based Photothermal Agents with Excellent Phototoxic Indices for Cancer Treatment.

Here, we report six novel, easily accessible BODIPY-based agents for cancer treatment. In contrast to established photodynamic therapy (PDT) agents, these BODIPY-based compounds show additional photothermal activity and their cytotoxicity is not dependent on the generation of reactive oxygen species (ROS). The agents show high photocytotoxicity upon irradiation with light and low dark toxicity in different cancer cell lines in 2D culture as well as in 3D multicellular tumor spheroids (MCTSs). The ratio of dark to light toxicity (phototoxic index, PI) of these agents reaches striking values exceeding 830,000 after irradiation with energetically low doses of light at 630 nm. The oxygen-dependent mechanism of action (MOA) of established photosensitizers (PSs) hampers effective clinical deployment of these agents. Under hypoxic conditions (0.2% O2), which are known to limit the efficiency of conventional PSs in solid tumors, photocytotoxicity was induced at the same concentration levels, indicating an oxygen-independent photothermal MOA. With a PI exceeding 360,000 under hypoxic conditions, both PI values are the highest reported to date. We anticipate that small molecule agents with a photothermal MOA, such as the BODIPY-based compounds reported in this work, may overcome this barrier and provide a new avenue to cancer therapy.

The TNF ΔARE mouse as a model of intestinal fibrosis.

Background & Aims: Crohn's disease (CD) is a highly morbid chronic inflammatory disease. The majority of CD patients also develop fibrostenosing complications. Despite this, there are no medical therapies for intestinal fibrosis. This is in part due to lack of high-fidelity biomimetic models to enhance understanding and drug development. There is a need to develop in vivo models of inflammatory bowel disease-related intestinal fibrosis. We sought to determine if the TNF ΔARE mouse, a model of ileal inflammation, may also develop intestinal fibrosis. Methods: Several clinically relevant outcomes were studied including features of structural fibrosis, histological fibrosis, and gene expression. These include the use of a luminal casting technique we developed, traditional histological outcomes, use of second harmonic imaging, and quantitative PCR. These features were studied in aged TNF ΔARE mice as well as in cohorts of numerous ages. Results: At ages of 24+ weeks, TNF ΔARE mice develop structural, histological, and genetic changes of ileal fibrosis. Genetic expression profiles have changes as early as six weeks, followed by histological changes occurring as early as 14-15 weeks, and overt structural fibrosis delayed until after 24 weeks. Discussion: The TNF ΔARE mouse is a viable and highly tractable model of intestinal fibrosis. This model and the techniques employed can be leveraged for both mechanistic studies and therapeutic development for the treatment of intestinal fibrosis.

Tobacco Hornworm as an Insect Model System for Cannabinoid Pre-clinical Studies.

With increased attention on cannabinoids in medicine, several mammalian model organisms have been used to elucidate their unknown pharmaceutical functions. However, many difficulties remain in mammalian research, which necessitates the development of non-mammalian model organisms for cannabinoid research. The authors suggest the tobacco hornworm Manduca sexta as a novel insect model system. This protocol provides information on preparing the artificial diet with varying amounts of cannabidiol (CBD), setting up a cultivation environment, and monitoring their physiological and behavioral changes in response to CBD treatment. Briefly, upon receiving hornworm eggs, the eggs were allowed 1-3 days at 25 °C on a 12:12 light-dark cycle to hatch before being randomly distributed into control (wheat germ-based artificial diet; AD), vehicle (AD + 0.1% medium-chain triglyceride oil; MCT oil) and treatment groups (AD + 0.1% MCT + 1 mM or 2 mM of CBD). Once the media was prepared, 1st instar larvae were individually placed in a 50 mL test tube with a wooden skewer stick, and then the test tube was covered with a cheesecloth. Measurements were taken in 2-day intervals for physiological and behavioral responses to the CBD administration. This simple cultivation procedure allows researchers to test large specimens in a given experiment. Additionally, the relatively short life cycles enable researchers to study the impact of cannabinoid treatments over multiple generations of a homogenous population, allowing for data to support an experimental design in higher mammalian model organisms.