It is likely that different chemotherapeutic drugs act through a range of mechanisms and on different target cells. More research into the cellular mechanisms underpinning chemotherapy-induced follicle loss could lead to the generation of treatments specifically designed to prevent POF.

Rationale Depletion of medial smooth muscle cell (SMC) is a major pathological characteristic of abdominal aortic aneurysm (AAA), although the mechanism by which these cells are eliminated remains incompletely understood. We reasoned that necroptosis, a recently described form of necrosis mediated by receptor-interacting protein kinase 3 (RIP3), may contribute to AAA pathology through the induction of SMC death and the significant production of inflammatory cytokines. Objective To test the hypothesis that RIP3-mediated necroptosis is actively involved in aneurysm pathogenesis. Methods and Results RIP3 and RIP1 levels were found to be elevated in human AAAs, most noticeably in SMCs. Elevations of RIP3 and SMC necrosis were also observed in the elastase-induced mouse model of AAAs. Deletion of one or both copies of Rip3 prevented AAA formation. By transplanting Rip3+/- aortae to Rip3+/+ mice, we demonstrated that reduced Rip3 expression in arterial wall was the primary cause of aneurysm resistance. In vitro, adenoviral overexpression of RIP3 was sufficient to trigger SMC necroptosis. PKCδ contributed to TNFα-induced SMC necroptosis by regulating Rip3 expression. Furthermore, Rip3 deficiency impaired TNFα-induced inflammatory gene expression in aortic SMCs, which was at least in part due to attenuation of p65 Ser536 phosphorylation. In vivo, the lack of RIP3 diminished activation of p65 in SMCs, implicating a necrosis independent function of RIP3 in aneurysms. Conclusions Enhanced RIP3-signaling in aneurysmal tissues contributes to AAA progression by causing SMC necroptosis as well as stimulating vascular inflammation, and therefore may serve as a novel therapeutic target for AAA treatment.

PurposeChemotherapy treatment in premenopausal women has been linked to ovarian follicle loss and premature ovarian failure; the exact mechanism by which this occurs is uncertain. Here, two commonly used chemotherapeutic agents (cisplatin and doxorubicin) were added to a mouse ovary culture system, to compare the sequence of events that leads to germ cell loss. The ability of imatinib mesylate to protect the ovary against cisplatin or doxorubicin-induced ovarian damage was also examined.Experimental designNewborn mouse ovaries were cultured for a total of six days, exposed to a chemotherapeutic agent on the second day: this allowed for the examination of the earliest stages of follicle development. Cleaved PARP and TUNEL were used to assess apoptosis following drug treatment. Imatinib was added to cultures with cisplatin and doxorubicin to determine any protective effect.ResultsHistological analysis of ovaries treated with cisplatin showed oocyte-specific damage; in comparison doxorubicin preferentially caused damage to the granulosa cells. Cleaved PARP expression significantly increased for cisplatin (16 fold, p<0.001) and doxorubicin (3 fold, p<0.01). TUNEL staining gave little evidence of primordial follicle damage with either drug. Imatinib had a significant protective effect against cisplatin-induced follicle damage (p<0.01) but not against doxorubicin treatment.ConclusionCisplatin and doxorubicin both induced ovarian damage, but in a markedly different pattern, with imatinib protecting the ovary against damage by cisplatin but not doxorubicin. Any treatment designed to block the effects of chemotherapeutic agents on the ovary may need to be specific to the drug(s) the patient is exposed to.

Rationale Histological examination of abdominal aortic aneurysm (AAA) tissues demonstrates extracellular matrix (ECM) destruction and infiltration of inflammatory cells. Previous work with mouse models of AAA has shown that anti-inflammatory strategies can effectively attenuate aneurysm formation. Thrombospondin-1 (TSP1) is a matricellular protein involved in the maintenance of vascular structure and homeostasis through the regulation of biological functions such as cell proliferation, apoptosis, and adhesion. Expression levels of TSP1 correlate with vascular disease conditions. Objective To use TSP1 deficient (Thbs1−/−) mice to test the hypothesis that TSP1 contributes to pathogenesis of AAAs. Methods and Results Mouse experimental AAA was induced either through perivascular treatment with calcium phosphate, intraluminal perfusion with porcine elastase, or systemic administration of Angiotensin II. Induction of AAA increased TSP1 expression in aortas of C57BL/6 or apoE−/− mice. Compared to Thbs1+/+ mice, Thbs1−/− mice developed significantly smaller aortic expansion when subjected to AAA inductions, which was associated with diminished infiltration of macrophages. Thbs1−/− monocytic cells had reduced adhesion and migratory capacity in vitro compared to wildtype counterparts. Adoptive transfer of Thbs1+/+ monocytic cells or bone marrow reconstitution rescued aneurysm development in Thbs1−/− mice. Conclusions TSP1 expression plays a significant role in regulation of migration and adhesion of mononuclear cells, contributing to vascular inflammation during AAA development.

Contrast-enhanced MRI of the sacroiliac joint is sensitive in depicting sacroiliitis in patients with established ankylosing spondylitis. Subchondral edema and enhancement correlate with high CRP levels. Subchondral fatty bone marrow changes were seen in both active and chronic sacroiliitis and are correlated with higher radiographic scores; these changes may be a marker of more advanced disease.