Ourlad Alzeus G. Tantengco

Bio: Ourlad Alzeus G. Tantengco is an academic researcher from University of the Philippines Manila. The author has contributed to research in topics: Medicine & Pregnancy. The author has an hindex of 5, co-authored 29 publications receiving 113 citations. Previous affiliations of Ourlad Alzeus G. Tantengco include Boston Children's Hospital & University of Texas Medical Branch.

Cytotoxic activity of crude extracts and fractions from Premna odorata (Blanco), Artocarpus camansi (Blanco) and Gliricidia sepium (Jacq.) against selected human cancer cell lines

Abstract: Objective To evaluate the cytotoxic activities of Premna odorata ( P. odorata ) leaves and bark, Artocarpus camansi ( A. camansi ) and Gliricidia sepium against selected human cancer cell lines by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Methods The crude extracts of P. odorata , A. camansi and Gliricidia sepium were subjected to liquid–liquid partitioning by using hexane and ethyl acetate to separate compounds based on their polarity. The fractions were tested for their cytotoxic activity against human colon cancer cell line (HCT116), breast cancer cell line (MCF-7), lung adenocarcinoma cell line (A549) and Chinese hamster ovary cell line (AA8) by using MTT assay. Results Based on the standard values of toxicity set by the study of Suffness and Pezzuto, P. odorata leaves and P. odorata bark hexane fractions and A. camansi leaves were all considered highly cytotoxic against the selected human cancer cell lines. P. odorata bark hexane extract exhibited the highest selectivity index for HCT116, MCF-7 and A549 cancer cell lines. Conclusions The results obtained indicated that P. odorata leaves and bark and A. camansi leaves have excellent cytotoxic activity and warrant further studies to isolate novel compounds for chemotherapeutic use.

Organ-on-chip of the cervical epithelial layer: A platform to study normal and pathological cellular remodeling of the cervix.

Abstract: Damage to the cervical epithelial layer due to infection and inflammation is associated with preterm birth. However, the individual and/or collective roles of cervical epithelial layers in maintaining cervical integrity remain unclear during infection/inflammation. To determine the intercellular interactions, we developed an organ-on-chip of the cervical epithelial layer (CE-OOC) composed of two co-culture chambers connected by microchannels, recapitulating the ectocervical and endocervical epithelial layers. Further, we tested the interactions between cells from each distinct region and their contributions in maintaining cervical integrity in response to LPS and TNFα stimulations. The co-culture of ectocervical and endocervical cells facilitated cellular migration of both epithelial cells inside the microchannels. Compared to untreated controls, both LPS and TNFα increased apoptosis, necrosis, and senescence as well as increased pro-inflammatory cytokine productions by cervical epithelial cells. In summary, the CE-OOC established an in vitro model that can recapitulate the ectocervical and the endocervical epithelial regions of the cervix. The established CE-OOC may become a powerful tool in obstetrics and gynecology research such as in studying cervical remodeling during pregnancy and parturition and the dynamics of cervical epithelial cells in benign and malignant pathology in the cervix.

Microvesicles and exosomes released by amnion epithelial cells under oxidative stress cause inflammatory changes in uterine cells

Abstract: Extracellular vesicles play a crucial role in feto-maternal communication and provide an important paracrine signaling mechanism in pregnancy. We hypothesized that fetal cells-derived exosomes and microvesicles (MVs) under oxidative stress (OS) carry unique cargo and traffic through feto-maternal interface, which cause inflammation in uterine cells associated with parturition. Exosomes and MVs, from primary amnion epithelial cell (AEC) culture media under normal or OS-induced conditions, were isolated by optimized differential centrifugation method followed by characterization for size (nanoparticle tracking analyzer), shape (transmission electron microscopy), and protein markers (western blot and immunofluorescence). Cargo and canonical pathways were identified by mass spectroscopy and ingenuity pathway analysis. Myometrial, decidual, and cervical cells were treated with 1 × 107 control/OS-derived exosomes/MVs. Pro-inflammatory cytokines were measured using a Luminex assay. Statistical significance was determined by paired T-test (P < 0.05). AEC produced cup-shaped exosomes of 90–150 nm and circular MVs of 160–400 nm. CD9, heat shock protein 70, and Nanog were detected in exosomes, whereas OCT-4, human leukocyte antigen G, and calnexin were found in MVs. MVs, but not exosomes, were stained for phosphatidylserine. The protein profiles for control versus OS-derived exosomes and MVs were significantly different. Several inflammatory pathways related to OS were upregulated that were distinct between exosomes and MVs. Both OS-derived exosomes and MVs significantly increased pro-inflammatory cytokines (granulocyte-macrophage colony-stimulating factor, interleukin 6 (IL-6), and IL-8) in maternal cells compared with control (P < 0.05). Our findings suggest that fetal-derived exosomes and MVs under OS exhibited distinct characteristics and a synergistic inflammatory role in uterine cells associated with the initiation of parturition. Summary sentence Oxidative stress-induced fetal membrane cells produce exosomes and MVs with distinct properties and cargo and may function as paracrine signalers at the feto-maternal interface during pregnancy and parturition. Graphical Abstract

Current understanding and treatment of intra-amniotic infection with Ureaplasma spp.

Abstract: Considerable evidence has shown that intra-amniotic infection with Ureaplasma spp. increases the risk of chorioamnionitis and preterm labor. Ureaplasma spp. are among the smallest organisms, and their isolation is uncommon in routine clinical practice because of their size and high auxotrophy. Although Ureaplasma spp. have been reported as causative agents of preterm birth, they also have a high incidence in vaginal swabs collected from healthy reproductive-age women; this has led to questions on the virulence of Ureaplasma spp. and to them being considered as harmless commensal bacteria. Therefore, many efforts have been made to clarify the pathogenicity of Ureaplasma spp. at the molecular level. Ureaplasma spp. are surrounded by lipoproteins, including multiple-banded antigen. Both multiple-banded antigen and its derivative, that is, the synthetic lipopeptide, UPM-1, induce an inflammatory response in a preterm mice model, which was adequate to cause preterm birth or stillbirth. In this review, we present an overview of the virulence mechanisms of Ureaplasma spp. and treatment of ureaplasma infection during pregnancy to prevent possible serious sequelae in infants. In addition, relevant mechanisms underlying antibiotic resistance in Ureaplasma spp. are discussed. Ureaplasma spp. are naturally resistant against β-lactam antibiotics because of the lack of a cell wall. Azithromycin is one of the effective agents that can control intrauterine ureaplasma infection. In fact, macrolide- and fluoroquinolone-resistant isolates of Ureaplasma spp. have already been observed in perinatal practice in Japan.

Lead Phytochemicals for Anticancer Drug Development.

Abstract: Cancer is a serious concern at present. A large number of patients die each year due to cancer illnesses in spite of several interventions available. Development of an effective and side effects lacking anticancer therapy is the trending research direction in healthcare pharmacy. Chemical entities present in plants proved to be very potential in this regard. Bioactive phytochemicals are preferential as they pretend differentially on cancer cells only, without altering normal cells. Carcinogenesis is a complex process and includes multiple signaling events. Phytochemicals are pleiotropic in their function and target these events in multiple manners; hence they are most suitable candidate for anticancer drug development. Efforts are in progress to develop lead candidates from phytochemicals those can block or retard the growth of cancer without any side effect. Several phytochemicals manifest anticancer function in vitro and in vivo. This article deals with these lead phytomolecules with their action mechanisms on nuclear and cellular factors involved in carcinogenesis. Additionally, druggability parameters and clinical development of anticancer phytomolecules have also been discussed.