Hypoxia-induced amniotic fluid stem cell secretome augments cardiomyocyte proliferation and enhances cardioprotective effects under hypoxic-ischemic conditions.

Secretome derived from human amniotic fluid stem cells (AFSC-S) is rich in soluble bioactive factors (SBF) and offers untapped therapeutic potential for regenerative medicine while avoiding putative cell-related complications. Characterization and optimal generation of AFSC-S remains challenging. We hypothesized that modulation of oxygen conditions during AFSC-S generation enriches SBF and confers enhanced regenerative and cardioprotective effects on cardiovascular cells. We collected secretome at 6-hourly intervals up to 30 h following incubation of AFSC in normoxic (21%O2, nAFSC-S) and hypoxic (1%O2, hAFSC-S) conditions. Proliferation of human adult cardiomyocytes (hCM) and umbilical cord endothelial cells (HUVEC) incubated with nAFSC-S or hAFSC-S were examined following culture in normoxia or hypoxia. Lower AFSC counts and richer protein content in AFSC-S were observed in hypoxia. Characterization of AFSC-S by multiplex immunoassay showed higher concentrations of pro-angiogenic and anti-inflammatory SBF. hCM demonstrated highest proliferation with 30h-hAFSC-S in hypoxic culture. The cardioprotective potential of concentrated 30h-hAFSC-S treatment was demonstrated in a myocardial ischemia-reperfusion injury mouse model by infarct size and cell apoptosis reduction and cell proliferation increase when compared to saline treatment controls. Thus, we project that hypoxic-generated AFSC-S, with higher pro-angiogenic and anti-inflammatory SBF, can be harnessed and refined for tailored regenerative applications in ischemic cardiovascular disease.

Tissues derived from reprogrammed Wharton's jelly stem cells of the umbilical cord as a platform to study gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) has been strongly associated with an increased risk of type 2 diabetes mellitus (T2DM) in later child and adulthood. The human umbilical cord and its contents are of fetal origin and represent the fetus genetically and physiologically. Since it is not possible to obtain tissues from the fetus and newborn to investigate the association between GDM and later T2DM, we reprogrammed the stem cells from the Wharton's jelly of umbilical cords (hWJSCs) of GDM and non-GDM mothers into induced pluripotent stem cells (iPSCs) and then differentiated the iPSCs into insulin-producing cells (IPCs) to provide pancreatic tissues that represent the fetus of GDM and normal mothers. These tissues are an attractive model to study the effects of glucose on the fetus. Interestingly, GDM-iPSCs had a decreased potential towards differentiation into IPCs. IPCs differentiated from GDM-iPSCs also had lower total insulin content and a lower capacity for insulin secretion to glucose stimulation compared to their normal-iPSC counterparts. This abnormal pathogenesis in GDM-iPSCs pancreatic differentiation recapitulates the pathology that may be observed in the infants of the diabetic mother (IDM) and while indicating adaptive mechanisms for fetal survival, may lead to the development of T2DM later in life. (199 words).

Inhibition of growth of Asian keloid cells with human umbilical cord Wharton's jelly stem cell-conditioned medium.

BACKGROUND: Keloid formation occurs in Caucasian, African, and Asian populations and is a severe psychosocial burden on patients. There is no permanent treatment for this problem as its pathogenesis is not properly understood. Furthermore, differences in keloid behavior between ethnic groups are not known. It has been hypothesized that keloids behave like benign tumors because of their uncontrolled growth. The present study evaluated the tumoricidal properties of human Wharton's jelly stem cell-conditioned medium (hWJSC-CM) on fresh Asian keloid cells (AKCs). METHODS: Human Wharton's jelly stem cells (hWJSCs) and AKCs were isolated based on our previous methods. hWJSCs and human skin fibroblasts (HSF) (controls) were used to collect hWJSC-CM and HSF-conditioned medium (HSF-CM). AKCs were treated with hWJSC-CM and HSF-CM in vitro and in vivo in a human keloid xenograft SCID mouse model. The inhibitory effect of hWJSC-CM on AKCs was tested in vitro using various assays and in vivo for attenuation/abrogation of AKC tumors created in a xenograft mouse model. RESULTS: qRT-PCR analysis showed that the genes FN1, MMP1, and VCAN were significantly upregulated in AKCs and ANXA1, ASPN, IGFBP7, LGALS1, and PTN downregulated. AKCs exposed to hWJSC-CM in vitro showed significant decreases in cell viability and proliferation, increases in Annexin V-FITC+ cell numbers, interruptions of the cell cycle at Sub-G1 and G2/M phases, altered CD marker expression, downregulated anti-apoptotic-related genes, and upregulated pro-apoptotic and autophagy-related genes compared to controls. When AKCs were administered together with hWJSC-CM into immunodeficient mice there were no keloid tumors formed in 7 mice (n = 10) compared to the untreated control mice. When hWJSC-CM was injected directly into keloid tumors created in mice there were significant reductions in keloid tumor volumes and weights in 30 days. CONCLUSIONS: hWJSC-CM inhibited the growth of AKCs in vitro and in xenograft mice, and it may be a potential novel treatment for keloids in the human. The specific molecule(s) in hWJSC-CM that induce the anti-keloid effect need to be identified, characterized, and tested separately in larger preclinical and clinical studies.

In silico studies on marine actinomycetes as potential inhibitors for Glioblastoma multiforme.

Glioblastoma multiforme (GBM) is considered to be the most common and often deadly disorder which affects the brain. It is caused by the over expression of proteins such as ephrin type-A receptor 2 (EphA2), epidermal growth factor receptor (EGFR) and EGFRvIII. These 3 proteins are considered to be the potential therapeutic targets for GBM. Among these, EphA2 is reported to be over-expressed in ˜90% of GBM. Herein we selected 35 compounds from marine actinomycetes, 5 in vitro and in vivo studied drug candidates and 4 commercially available drugs for GBM which were identified from literature and analysed by using comparative docking studies. Based on the glide scores and other in silico parameters available in Schrödinger, two selected marine actinomycetes compounds which include Tetracenomycin D and Chartreusin exhibited better binding energy among all the compounds studied in comparative docking. In this study we have demonstrated the inhibition of the 3 selected targets by the two bioactive compounds from marine actinomycetes through in-silico docking studies. Furthermore molecular dynamics simulation were also been performed to check the stability and the amino acids interacted with the 3 molecular targets (EphA2 receptor, EGFR, EGFRvIII) for GBM. Our results suggest that Tetracinomycin D and Chartreusin are the novel and potential inhibitor for the treatment of GBM.