Crohn’s disease (CD) is a relapsing chronic inflammatory disorder that may involve all the gastrointestinal tract with a prevalence of terminal ileum. Intestinal lesions have a characteristic discontinuous and segmental distribution and may affect all layers of the gut wall. Telocytes (TC), a peculiar type of stromal cells, have been recently identified in a variety of tissues and organs, including gastrointestinal tract of humans and mammals. Several roles have been proposed for TC, including mechanical support, spatial relationships with different cell types, intercellular signalling and modulation of intestinal motility. The aim of our study was to investigate the presence and distribution of TC in disease-affected and -unaffected ileal specimens from CD patients compared with controls. TC were identified by CD34/PDGFRα immunohistochemistry. In affected CD specimens TC disappeared, particularly where fibrosis and architectural derangement of the intestinal wall were observed. In the thickened muscularis mucosae and submucosa, few TC entrapped in the fibrotic extracellular matrix were found. A discontinuous network of TC was present around smooth muscle bundles, ganglia and enteric strands in the altered muscularis propria. At the myenteric plexus, the loss of TC network was paralleled by the loss of interstitial cells of Cajal network. In the unaffected CD specimens, TC were preserved in their distribution. Our results suggest that in CD the loss of TC might have important pathophysiological implications contributing to the architectural derangement of the intestinal wall and gut dysmotility. Further functional studies are necessary to better clarify the role of TC loss in CD pathophysiology.

Hemodynamic and tubular factors modify renal sodium handling in AT2 receptor knockout mice and may cause hypertension. AT2 receptor disruption induces alterations of other regulatory systems, including altered arachidonic acid metabolism, that may contribute to the intrarenal differences observed between AT2 receptor knockout and wild-type mice.

IL33 and ST2 are abnormally expressed in SSc. In early SSc, upon EC activation/damage IL33 may be mobilised from ECs to signal through ST2 in key profibrotic players such as inflammatory/immune cells and fibroblasts/myofibroblasts.

uPAR(-/-) mice are a new animal model closely mimicking the histopathological features of SSc. This model warrants future studies.

Background— Microvascular insufficiency represents a major cause of end-organ failure among diabetics. Methods and Results— In streptozotocin-induced diabetic mice, we evaluated the potential of human tissue kallikrein (hTK) gene as a sole therapy against peripheral microangiopathy. Local delivery of hTK gene halted the progression of microvascular rarefaction in hindlimb skeletal muscle by inhibiting apoptosis, thus ensuring an improved hemodynamic recovery in case of supervening vascular occlusion. The curative action of hTK did not necessitate insulin supplementation. Application of gene therapy at a stage of established microangiopathy stimulated vascular regeneration. Conclusions— Our studies indicate that hTK may represent a useful tool for the treatment of microvascular complications in diabetics.

Endocrine function was evaluated in 20 prepubertal patients with homozygous beta-thalassemia treated with frequent transfusions and long term iron chelation therapy. FSH, LH, PRL, and TSH secretion were evaluated by LRH and TRH testing and L-dopa and ACTH were used to assess GH and adrenocortical reserve. No statistically significant differences were found between FSH, LH, PRL, GH, and cortisol secretion in the patients and in normal subjects. There was a relatively high incidence (35%) of primary thyroid impairment since 1 patient had primary hypothyroidism and 6 others had evidence of subclinical hypothyroidism as manifested by increased TSH responses to TRH. However, no statistically significant correlations were found between either serum ferritin levels, total blood transfusions received, and thyroid function.

SSc-MSCs constitutively overexpress and release bioactive mediators/proangiogenic factors and potentiate dermal MVEC angiogenesis.

Abstract-Proteinase-activated receptors (PAR-2) are expressed by the cardiovascular system and mediate vasodilation, plasma protein extravasation, and endothelial cell proliferation, all regarded as essential steps for neovascularization. We investigated the angiogenic action of PAR-2 signaling in vivo. The effect of the PAR-2 activating peptide (PAR-2AP, SLIGRL-NH 2 ) was assessed in the absence of ischemia, and the therapeutic potential of PAR-2AP and the PAR-2 agonist trypsin (at 300 and 1.5 nmol IM daily for 21 days, respectively) was also tested in mice subjected to unilateral limb ischemia. PAR-2AP increased capillarity in normoperfused adductor skeletal muscles, whereas neither the vehicle of the PAR2-AP nor the PAR-2 reverse peptide (PAR-2RP, LRGILS-NH 2 ) did produce any effect. In addition, both PAR-2AP and trypsin enhanced reparative angiogenic response to limb ischemia, an effect that was not produced by PAR-2RP or the vehicle of PAR-2 agonists. Potentiation of reparative angiogenesis by PAR-2AP or trypsin resulted in an accelerated hemodynamic recovery and enhanced limb salvage. In conclusions, our study is the first to demonstrate the angiogenic potential of PAR-2 stimulation in vivo.