Doxorubicin (Dox) is an effective antineoplastic agent used to treat cancers, but its use is limited as Dox induces adverse cardiotoxic effects. Dox-induced cardiotoxicity (DIC) can lead to heart failure and death. There is no study that investigates whether embryonic stem cell-derived exosomes (ES-Exos) in DIC can attenuate inflammation-induced pyroptosis, pro-inflammatory M1 macrophages, inflammatory cell signaling, and adverse cardiac remodeling. For this purpose, we transplanted ES-Exos and compared with ES-cells (ESCs) to examine pyroptosis, inflammation, cell signaling, adverse cardiac remodeling, and their influence on DIC induced cardiac dysfunction. Therefore, we used C57BL/6J mice ages 10 ± 2 weeks and divided them into four groups (n = 6–8/group): Control, Dox, Dox + ESCs, and Dox + ES-Exos. Our data shows that the Dox treatment significantly increased expression of inflammasome markers (TLR4 and NLRP3), pyroptotic markers (caspase-1, IL1-β, and IL-18), cell signaling proteins (MyD88, p-P38, and p-JNK), pro-inflammatory M1 macrophages, and TNF-α cytokine. This increased pyroptosis, inflammation, and cell signaling proteins were inhibited with ES-Exos or ESCs. Moreover, ES-Exos or ESCs increased M2 macrophages and anti-inflammatory cytokine, IL-10. Additionally, ES-Exos or ESCs treatment inhibited significantly cytoplasmic vacuolization, myofibril loss, hypertrophy, and improved heart function. In conclusion, for the first time we demonstrated that Dox-induced pyroptosis and cardiac remodeling are ameliorated by ES-Exos or ESCs.

Doxorubicin (Doxo) is an effective agent commonly used in cancer therapeutics. Unfortunately, Doxo treatment can stimulate cardiomyopathy and subsequent heart failure, limiting use of this drug. The role of phosphatase and tensin homolog (PTEN) in apoptosis has been documented in Doxo induced cardiomyopathy (DIC) and heart failure models. However, whether direct inhibition of PTEN attenuates apoptosis, cardiac remodeling, and inflammatory M1 macrophages in DIC model remains elusive. Therefore, the current study is designed to understand effects of VO-OHpic (VO), a potent inhibitor of PTEN, in reducing apoptosis and cardiac remodeling. At D56, echocardiography was performed, which shows VO-OHpic treatment significantly (p<0.05) improves heart function. Immunohistochemistry, TUNEL, and histological staining were used to determine apoptosis, pro-inflammatory M1 macrophages, anti-inflammatory M2 macrophages, and cardiac remodeling. Our data shows a significant increase in apoptosis, hypertrophy, fibrosis, and pro-inflammatory M1 macrophages with Doxo treatment, whereas VO treatment significantly reduced apoptosis, adverse cardiac remodeling, and pro-inflammatory M1 macrophages significantly (p<0.05) compared to Doxo group. Western blotting confirmed the reduction of p-PTEN and increase in p-AKT protein expression in the Doxo+VO group. Moreover, VO administration increased anti-inflammatory M2 macrophages. Collectively, our data suggests that VO-OHpic treatment attenuates apoptosis and adverse cardiac remodeling, a process that is mediated through PTEN/AKT pathway, resulting in improved heart function in DIC.

Doxorubicin (Dox) is an effective anticancer drug. Unfortunately, it causes cardiac and muscle toxicity due to increased oxidative stress and inflammation; however, it remains unknown whether Dox induces "pyroptosis" - an inflammation-mediated cell death. We investigated whether Dox induces pyroptosis in mouse soleus muscle (Sol 8) cells in vitro and to show the protective effect of embryonic stem cell exosomes (ES-exos) on pyroptosis. Dox and inflammation-induced in vitro model was generated. Pyroptosis was confirmed using immunohistochemistry (with putative markers caspase-1, IL-1β, and pro-inflammatory cytokine IL-18) and Western blotting of caspase-1 and IL-1β. The results show significant increase in the expression of caspase-1, IL-1β, and IL-18 following treatment with Dox, which was inhibited by ES-exos but not mouse embryonic fibroblast exosomes. Moreover, GW4869 compound inhibited functional activity of ES-exos, suggesting these vesicles are key players in the inhibition of pyroptosis. These results suggest that Dox induces inflammatory pyroptosis in Sol 8 cells, which is attenuated by ES-exos in vitro.

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While numerous computer models exist for the circulatory system, many are limited in scope, contain unwanted features or incorporate complex components specific to unique experimental situations. Our purpose was to develop a basic, yet multifaceted, computer model of the left heart and systemic circulation in LabVIEW having universal appeal without sacrificing crucial physiologic features. The program we developed employs Windkessel-type impedance models in several open-loop configurations and a closed-loop model coupling a lumped impedance and ventricular pressure source. The open-loop impedance models demonstrate afterload effects on arbitrary aortic pressure/flow inputs. The closed-loop model catalogs the major circulatory waveforms with changes in afterload, preload, and left heart properties. Our model provides an avenue for expanding the use of the ventricular equations through closed-loop coupling that includes a basic coronary circuit. Tested values used for the afterload components and the effects of afterload parameter changes on various waveforms are consistent with published data. We conclude that this model offers the ability to alter several circulatory factors and digitally catalog the most salient features of the pressure/flow waveforms employing a user-friendly platform. These features make the model a useful instructional tool for students as well as a simple experimental tool for cardiovascular research.

In mammalian testes, premeiotic spermatogonia respond to retinoic acid (RA) by completing an essential lengthy differentiation program before initiating meiosis. The molecular and cellular changes directing these developmental processes remain largely undefined. This wide gap in knowledge is due to two critical unresolved technical challenges: 1) lack of robust and reliable in vitro models to study differentiation and meiotic initiation; 2) lack of methods to isolate large and pure populations of male germ cells at each stage of differentiation and at meiotic initiation. Here, we report a facile in vitro differentiation and meiotic initiation system that can be readily manipulated, including the use of chemical agents that cannot be safely administered to live animals. In addition, we present a transgenic mouse model enabling fluorescence-activated cell sorting (FACS)-based isolation of millions of spermatogonia at specific developmental stages as well as meiotic spermatocytes.

Breast cancer is one of the most prevalent forms of cancer in the United States and worldwide. Cancer occurs through the uncontrolled development of new abnormal cell growth. Clinicians and researchers strive to improve diagnostics and treatments in pursuit of remedying breast cancer, while limiting or removing any potential side effects that may arise. Unfortunately, traditional treatments, such as anthracyclines (i.e., doxorubicin), can damage the cardiovascular system. Recent strategies have utilized antibody-based compounds as singular treatments, or in conjunction with other treatments, with the aim to minimize side effects. The human epidermal growth factor receptor 2 (HER2) protein has been the target of numerous antibody-based breast cancer therapies, such as trastuzumab (TZM) and trastuzumab emtansine (T-DM1). This review will discuss the HER2 receptor as a diagnostic marker in targeting breast cancer using the therapeutic agents TZM and T-DM1, as well as discuss the induced cardiac toxicity following TZM and T-DM1 treatments.

Sirolimus, also known as rapamycin, and its closely-related rapamycin analog (rapalog) Everolimus inhibit ‘mammalian target of rapamycin complex 1’ (mTORC1), whose activity is required for spermatogenesis. Everolimus is FDA-approved for treating human patients to slow growth of aggressive cancers and preventing organ transplant rejection. Here, we test the hypothesis that rapalog inhibition of mTORC1 activity has a negative, but reversible, impact upon spermatogenesis. Juvenile (P20) or adult (P &gt; 60) mice received daily injections of sirolimus or Everolimus for 30 days, and tissues were examined at completion of treatment or following a recovery period. Rapalog treatments reduced body and testis weights, testis weight/body weight ratios, cauda epididymal sperm counts, and seminal vesicle weights in animals of both ages. Following rapalog treatment, numbers of differentiating spermatogonia were reduced, with concomitant increases in the ratio of undifferentiated spermatogonia to total number of remaining germ cells. To determine if even low doses of Everolimus can inhibit spermatogenesis, an additional group of adult mice received a dose of Everolimus approximately 6-fold lower than a human clinical dose used to treat cancer. In these animals, only testis weights, testis weight/body weight ratios, and tubule diameters were reduced. Return to control values following a recovery period was variable for each of the measured parameters and was duration- and dose-dependent. Together, these data indicate rapalogs exerted a dose-dependent restriction on overall growth of juvenile and adult mice and negative impact upon spermatogenesis that were largely reversed; following treatment cessation, males from all treatment groups were able to sire offspring.