Peripheral nervous system genes expressed in central neurons induce growth on inhibitory substrates.

Trauma to the spinal cord and brain can result in irreparable loss of function. This failure of recovery is in part due to inhibition of axon regeneration by myelin and chondroitin sulfate proteoglycans (CSPGs). Peripheral nervous system (PNS) neurons exhibit increased regenerative ability compared to central nervous system neurons, even in the presence of inhibitory environments. Previously, we identified over a thousand genes differentially expressed in PNS neurons relative to CNS neurons. These genes represent intrinsic differences that may account for the PNS's enhanced regenerative ability. Cerebellar neurons were transfected with cDNAs for each of these PNS genes to assess their ability to enhance neurite growth on inhibitory (CSPG) or permissive (laminin) substrates. Using high content analysis, we evaluated the phenotypic profile of each neuron to extract meaningful data for over 1100 genes. Several known growth associated proteins potentiated neurite growth on laminin. Most interestingly, novel genes were identified that promoted neurite growth on CSPGs (GPX3, EIF2B5, RBMX). Bioinformatic approaches also uncovered a number of novel gene families that altered neurite growth of CNS neurons.

Cardiac fibrosis in mice with hypertrophic cardiomyopathy is mediated by non-myocyte proliferation and requires Tgf-ß.

Mutations in sarcomere protein genes can cause hypertrophic cardiomyopathy (HCM), a disorder characterized by myocyte enlargement, fibrosis, and impaired ventricular relaxation. Here, we demonstrate that sarcomere protein gene mutations activate proliferative and profibrotic signals in non-myocyte cells to produce pathologic remodeling in HCM. Gene expression analyses of non-myocyte cells isolated from HCM mouse hearts showed increased levels of RNAs encoding cell-cycle proteins, Tgf-ß, periostin, and other profibrotic proteins. Markedly increased BrdU labeling, Ki67 antigen expression, and periostin immunohistochemistry in the fibrotic regions of HCM hearts confirmed the transcriptional profiling data. Genetic ablation of periostin in HCM mice reduced but did not extinguish non-myocyte proliferation and fibrosis. In contrast, administration of Tgf-ß-neutralizing antibodies abrogated non-myocyte proliferation and fibrosis. Chronic administration of the angiotensin II type 1 receptor antagonist losartan to mutation-positive, hypertrophy-negative (prehypertrophic) mice prevented the emergence of hypertrophy, non-myocyte proliferation, and fibrosis. Losartan treatment did not reverse pathologic remodeling of established HCM but did reduce non-myocyte proliferation. These data define non-myocyte activation of Tgf-ß signaling as a pivotal mechanism for increased fibrosis in HCM and a potentially important factor contributing to diastolic dysfunction and heart failure. Preemptive pharmacologic inhibition of Tgf-ß signals warrants study in human patients with sarcomere gene mutations.

Targeting sphingolipid metabolism in head and neck cancer: rational therapeutic potentials.

IMPORTANCE OF THE FIELD: Ceramide accumulation has been shown to be a conserved mechanism of apoptosis initiation in normal physiological processes as well as in response to cancer treatments. Therefore, it is unsurprising that many cancers develop aberrations of sphingolipid metabolism that prevent the accumulation of ceramide, whether by reduction of ceramide generation or by enhanced ceramide catabolism, particularly dangerous when catabolism leads to generation of pro-tumor sphingosine-1-phosphate and ceramide-1-phosphate. Numerous studies have now implicated dysregulation of sphingolipid metabolism in head and neck cancers. AREAS COVERED IN THIS REVIEW: This review highlights the importance of sphingolipid metabolism and brings sphingolipid metabolism to the forefront in the investigation of novel therapies for head and neck cancer. It reviews sphingolipid-centric therapies under investigation in preclinical and clinical trials of cancers of the head and neck. WHAT THE READER WILL GAIN: The roles of sphingolipids and sphingolipid metabolism in cancer are reviewed and the reader will be brought up to date with discoveries in the field of sphingolipid metabolism in head and neck cancer. TAKE HOME MESSAGE: As treatments for head and neck cancers are currently limited, the potential of targeting sphingolipid metabolism should be taken into consideration as we seek novel ways to combat this group of tumors.

Detection and quantitation of curcumin in mouse lung cell cultures by matrix-assisted laser desorption ionization time of flight mass spectrometry.

A method to detect and quantify curcumin and two curcuminoid metabolites in biological matrices, including mouse serum and mouse lung cell cultures, was developed. Standard curves between 0.04 and 10.00 nmol curcumin were prepared in serum, giving correlation coefficients of 0.94-0.99. Alcoholic extraction, concentration, and addition of dilute hydrochloric acid to stabilize the curcumin were essential to the reproducibility of the protocol. Untreated and curcumin-treated mouse lung fibrotic and nonfibrotic cell cultures were analyzed by matrix-assisted laser desorption ionization time of flight mass spectrometry utilizing this method. Curcumin uptake was calculated to be 7.0-11.6% for the saline-treated cells and 7.4-11.9% for the bleomycin-treated cultures. Curcumin was not detected in untreated cells. Two additional peaks (m/z=399 and 429) were observed in the curcumin-treated cells. These may be curcumin-derived products resulting from HCl treatment of the tissue samples.