Evaluation of pancreatic δ- cells as a potential target site of graphene oxide toxicity in Japanese medaka (Oryzias latipes) fish.

In continuation to our previous investigations on graphene oxide (GO) as an endocrine disrupting chemical (EDC), in the present experiment, we have investigated endocrine pancreas of Japanese medaka adults focusing on δ-cells in the islet organs as an endpoint. Breeding pairs of adult male and female fish were exposed to 0 mg/L (control) or 20 mg/L GO by continuous immersion (IMR) for 96 h, or to 0 µg/g or 100 µg/g GO by a single intraperitoneal (IP) administration and depurated 21 days in a GO-free environment. Histological investigations indicated that the endocrine cells are concentrated in one large principal islet, and several small secondary islets scattered within the mesentery near the liver and intestine. The cells of the islet organ are in various shapes with basophilic nuclei and eosinophilic cytoplasm. Immunohistochemical evaluation using rabbit polyclonal antisomatostatin antibody indicated that immunoreactivity is localized either at the periphery or at the central region in principal islets, and throughout the secondary islets, and found to be enhanced in fish exposed to GO than controls. The soma of δ-cells exhibits neuron-like morphology and have filopodia like processes. Cell sorting as non-communicating δ-cells (NCDC), communicating cells (CC), and non- δ-cells (NDC) indicated that within an islet organ, the population of NDCC is found to be the least and NDC is the highest. Our data further indicated that GO-induced impairments in the islet organs of medaka pancreas are inconsistent and could be affected by the exposure roots as well as the sex of the fish.

The Management of Diabetes Mellitus Using Medicinal Plants and Vitamins.

Diabetes mellitus (DM) is a serious chronic metabolic disease that is associated with hyperglycemia and several complications including cardiovascular disease and chronic kidney disease. DM is caused by high levels of blood sugar in the body associated with the disruption of insulin metabolism and homeostasis. Over time, DM can induce life-threatening health problems such as blindness, heart disease, kidney damage, and stroke. Although the cure of DM has improved over the past decades, its morbidity and mortality rates remain high. Hence, new therapeutic strategies are needed to overcome the burden of this disease. One such prevention and treatment strategy that is easily accessible to diabetic patients at low cost is the use of medicinal plants, vitamins, and essential elements. The research objective of this review article is to study DM and explore its treatment modalities based on medicinal plants and vitamins. To achieve our objective, we searched scientific databases of ongoing trials in PubMed Central, Medline databases, and Google Scholar websites. We also searched databases on World Health Organization International Clinical Trials Registry Platform to collect relevant papers. Results of numerous scientific investigations revealed that phytochemicals present in medicinal plants (Allium sativum, Momordica charantia, Hibiscus sabdariffa L., and Zingiber officinale) possess anti-hypoglycemic activities and show promise for the prevention and/or control of DM. Results also revealed that intake of vitamins C, D, E, or their combination improves the health of diabetes patients by reducing blood glucose, inflammation, lipid peroxidation, and blood pressure levels. However, very limited studies have addressed the health benefits of medicinal plants and vitamins as chemo-therapeutic/preventive agents for the management of DM. This review paper aims at addressing this knowledge gap by studying DM and highlighting the biomedical significance of the most potent medicinal plants and vitamins with hypoglycemic properties that show a great potential to prevent and/or treat DM.

p53 as a unique target of action of cisplatin in acute leukaemia cells.

Acute promyelocytic leukaemia (APL) occurs in approximately 10% of acute myeloid leukaemia patients. Arsenic trioxide (ATO) has been for APL chemotherapy, but recently several ATO-resistant cases have been reported worldwide. Cisplatin (CDDP) enhances the toxicity of ATO in ovarian, lung cancer, chronic myelogenous leukaemia, and HL-60 cells. Hence, the goal of this study was to investigate a novel target of CDDP action in APL cells, as an alternate option for the treatment of ATO-resistant APL patients. We applied biochemical, molecular, confocal microscopy and advanced gene editing (CRISPR-Cas9) techniques to elucidate the novel target of CDDP action and its functional mechanism in APL cells. Our main findings revealed that CDDP activated p53 in APL cells through stress signals catalysed by ATM and ATR protein kinases, CHK1 and CHK2 phosphorylation at Ser 345 and Thr68 residues, and downregulation and dissociation of MDM2-DAXX-HAUSP complex. Our functional studies confirmed that CDDP-induced repression of MDM2-DAXX-HAUSP complex was significantly reversed in both nutilin-3-treated KG1a and p53-knockdown NB4 cells. Our findings also showed that CDDP stimulated an increased number of promyelocytes with dense granules, activated p53 expression, and downregulated MDM2 in liver and bone marrow of APL mice. Principal conclusion of our study highlights a novel mode of action of CDDP targeting p53 expression which may provide a basis for designing new anti-leukaemic compounds for treatment of APL patients.

Coupling a droplet generator with conventional ESI-MS for quantitative analysis of small-volume samples.

Quantitative mass spectrometric analysis of small-volume samples (e.g., < 1 µL) has been a challenge mainly due to the difficulties with sample handling and its injection into the system for analysis. Herein we report a microfluidic analytical platform coupling a droplet generator with conventional electrospray ionization-mass spectrometry (ESI-MS) that enables multiple analyses of a µL-sized sample with sensitivity and repeatability. In an analysis by droplet generator-assisted ESI-MS (DG-ESI-MS), a sample of µL volume is pulled into a sampling capillary and its equal nL-sized portions are generated by a droplet generator and analyzed by ESI-MS at time intervals of choice. The droplet generator is made of PMMA sheets by laser engraving conveniently and at a low cost. In a study to achieve effective ESI-MS detection of water-in-oil droplets, it's found that the problem of MS signal suppression by oil can be solved by using an appropriate organic carrier with ESI-enhancing additives. The proposed DG-ESI-MS method has linear calibration curves for both adenine and phenylalanine with LODs at the sub-µM level. Application of the present analytical platform for monitoring substrate concentration changes in an enzymatic reaction solution of 3 µL is demonstrated.

Histopathological evaluation of the interrenal gland (adrenal homolog) of Japanese medaka (Oryzias latipes) exposed to graphene oxide.

Due to unique physicochemical properties and wide industrial and biomedical applications, graphene oxide (GO) is ubiquitous in the aquatic ecosystem. Using Japanese medaka (Oryzias latipes) fish as a model, we previously demonstrated minimal endocrine disrupting (ED) effects of GO on reproductive organs, and thyroids. Current study investigated the ED-effects of GO on the interrenal gland (IRG) of medaka. Breeding pairs of adult male and female fish were exposed to 0 mg/L (control) or 20 mg/L GO by continuous immersion for 96 h, or to 0 or 100 µg/g GO by intraperitoneal administration. Also, 1 day post-hatch (dph) larvae were exposed to different concentrations of GO (2.5-20 mg/L) for 96 h. IRG was evaluated by immunohistochemical techniques after 21 days depuration in adults and 6 weeks in larvae. IRG cells were counted and the nuclear area was measured in hematoxylin-eosin stained sections using ImageJ software. We found that IRG is distributed adjacent to the posterior cardinal vein and its branches within the head kidney. Columnar/oval shaped periodic acid-Schiff negative, tyrosine hydroxylase positive cells are arranged either in a single, or in groups, sometimes encircling a sinusoid, or in a straight chord, laying adjacent to the endothelium of the cardinal vein, and having eosinophilic cytoplasm with round/oval basophilic nuclei. GO effect on nuclei and cell population in IRG was inconsistent; depending on exposure route, sex, and/or age of the fish. Also, because of its high adsorptive property and sharp edges, GO probably agglomerated on IRG, and induced physical injury, and ED effects.

Pharmacological Effects of Cisplatin Combination with Natural Products in Cancer Chemotherapy.

Cisplatin and other platinum-based drugs, such as carboplatin, ormaplatin, and oxaliplatin, have been widely used to treat a multitude of human cancers. However, a considerable proportion of patients often relapse due to drug resistance and/or toxicity to multiple organs including the liver, kidneys, gastrointestinal tract, and the cardiovascular, hematologic, and nervous systems. In this study, we sought to provide a comprehensive review of the current state of the science highlighting the use of cisplatin in cancer therapy, with a special emphasis on its molecular mechanisms of action, and treatment modalities including the combination therapy with natural products. Hence, we searched the literature using various scientific databases., such as MEDLINE, PubMed, Google Scholar, and relevant sources, to collect and review relevant publications on cisplatin, natural products, combination therapy, uses in cancer treatment, modes of action, and therapeutic strategies. Our search results revealed that new strategic approaches for cancer treatment, including the combination therapy of cisplatin and natural products, have been evaluated with some degree of success. Scientific evidence from both in vitro and in vivo studies demonstrates that many medicinal plants contain bioactive compounds that are promising candidates for the treatment of human diseases, and therefore represent an excellent source for drug discovery. In preclinical studies, it has been demonstrated that natural products not only enhance the therapeutic activity of cisplatin but also attenuate its chemotherapy-induced toxicity. Many experimental studies have also reported that natural products exert their therapeutic action by triggering apoptosis through modulation of mitogen-activated protein kinase (MAPK) and p53 signal transduction pathways and enhancement of cisplatin chemosensitivity. Furthermore, natural products protect against cisplatin-induced organ toxicity by modulating several gene transcription factors and inducing cell death through apoptosis and/or necrosis. In addition, formulations of cisplatin with polymeric, lipid, inorganic, and carbon-based nano-drug delivery systems have been found to delay drug release, prolong half-life, and reduce systemic toxicity while other formulations, such as nanocapsules, nanogels, and hydrogels, have been reported to enhance cell penetration, target cancer cells, and inhibit tumor progression.

Arsenic trioxide reduces the expression of E2F1, cyclin E, and phosphorylation of PI3K signaling molecules in acute leukemia cells.

Arsenic trioxide (ATO) has been used for the treatment of acute promyelocytic leukemia (APL). Although ATO modulates cell cycle progression and apoptosis in APL cells, its exact mechanism of action remains elusive. In this research, we investigated its effects on E2F1, cyclin E, p53, pRb, and PI3K signaling molecules by western blotting, immunocytochemistry and/or confocal imaging. We found that ATO inhibited the proliferation of APL cells through down-regulation of E2F1 and cyclin E expression, and stimulation of pRb. It also reduced the interaction of pRb and E2F1with binding to the E2F1 promoter, by stimulating pRb association. ATO also effected the phosphorylation of pRb at S608 and T373 residues and association of E2F1, pRb, and p53, simultaneously. However, in p53-knockdown NB4 cells, ATO did not significantly reduce E2F1 and cyclin E expression. Our findings demonstrate that ATO inhibits APL cell growth through reduced expression of E2F1, cyclin E, and stimulation of pRb. It also effected both interaction and association of E2F1, pRb, and p53 by phosphorylation of pRb at T373 and S608 residues and reduced phosphorylation of PI3K signaling molecules. This novel mode of action of ATO in APL cells may be useful for designing new APL drugs.

Kolaviron ameliorates hepatic and renal dysfunction associated with multiwalled carbon nanotubes in rats.

The increase in the exposure to carbon nanotubes (CNTs) and their incorporation into industrial, electronic, and biomedical products have required several scientific investigations into the toxicity associated with CNTs. Studies have shown that the metabolism and clearance of multiwalled CNTs (MWCNTs) from the body involve biotransformation in the liver and its excretion via the kidney. Since oxidative stress and inflammation underlines the toxicity of MWCNT, we investigated the ameliorative effect of kolaviron (KV), a natural antioxidant and anti-inflammatory agent, on hepatorenal damage in rats. Exposure to MWCNTs for 15 days significantly increased serum activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase thereby suggesting hepatic dysfunction. Kidney function, which was monitored by urea and creatinine levels, was also impaired by MWCNTs. Additionally, MWCNTs markedly increased myeloperoxidase activity, nitric oxide level, reactive oxygen and nitrogen species, and tumor necrosis factor level in both tissues. However, KV in a dose-dependent manner markedly attenuated MWCNT-induced markers of hepatorenal function in the serum and MWCNT-associated inflammation in the liver and kidney. Also, MWCNTs elicited significant inhibition of superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase activities. There was a significant diminution in glutathione level (GSH) and enhanced production of malondialdehyde (MDA) in MWCNTs-exposed rats. KV treatment was able to significantly increase the antioxidant enzymes and enhance the GSH level with a subsequent reduction in the MDA level. Taken together, KV elicited ameliorative effects against hepatorenal damage via its anti-inflammatory and antioxidant properties. Thus, KV could be an important intervention strategy for the hepatorenal damage associated with MWCNTs exposure.

Vernonia calvoana Shows Promise towards the Treatment of Ovarian Cancer.

The treatment for ovarian cancers includes chemotherapies which use drugs such as cisplatin, paclitaxel, carboplatin, platinum, taxanes, or their combination, and other molecular target therapies. However, these current therapies are often accompanied with side effects. Vernonia calvoana (VC) is a valuable edible medicinal plant that is widespread in West Africa. In vitro data in our lab demonstrated that VC crude extract inhibits human ovarian cancer cells in a dose-dependent manner, suggesting its antitumor activity. From the VC crude extract, we have generated 10 fractions and VC fraction 7 (F7) appears to show the highest antitumor activity towards ovarian cancer cells. However, the mechanisms by which VC F7 exerts its antitumor activity in cancer cells remain largely unknown. We hypothesized that VC F7 inhibits cell proliferation and induces DNA damage and cell cycle arrest in ovarian cells through oxidative stress. To test our hypothesis, we extracted and fractionated VC leaves. The effects of VC F7 were tested in OVCAR-3 cells. Viability was assessed by the means of MTS assay. Cell morphology was analyzed by acridine orange and propidium iodide (AO/PI) dye using a fluorescent microscope. Oxidative stress biomarkers were evaluated by the means of lipid peroxidation, catalase, and glutathione peroxidase assays, respectively. The degree of DNA damage was assessed by comet assay. Cell cycle distribution was assessed by flow cytometry. Data generated from the MTS assay demonstrated that VC F7 inhibits the growth of OVCAR-3 cells in a dose-dependent manner, showing a gradual increase in the loss of viability in VC F7-treated cells. Data obtained from the AO/PI dye assessment revealed morphological alterations and exhibited characteristics such as loss of cellular membrane integrity, cell shrinkage, cell membrane damage, organelle breakdown, and detachment from the culture plate. We observed a significant increase (p < 0.05) in the levels of malondialdhyde (MDA) production in treated cells compared to the control. A gradual decrease in both catalase and glutathione peroxidase activities were observed in the treated cells compared to the control. Data obtained from the comet assay showed a significant increase (p < 0.05) in the percentages of DNA cleavage and comet tail length. The results of the flow cytometry analysis indicated VC F7 treatment caused cell cycle arrest at the S-phase checkpoint. Taken together, our results demonstrate that VC F7 exerts its anticancer activity by inhibiting cell proliferation, inducing DNA damage, and causing cell cycle arrest through oxidative stress in OVAR-3 cells. This finding suggests that VC F7 may be a potential alternative dietary agent for the prevention and/or treatment of ovarian cancer.

Graphene-Based Nanomaterials Toxicity in Fish.

Due to their unique physicochemical properties, graphene-based nanoparticles (GPNs) constitute one of the most promising types of nanomaterials used in biomedical research. GPNs have been used as polymeric conduits for nerve regeneration and carriers for targeted drug delivery and in the treatment of cancer via photothermal therapy. Moreover, they have been used as tracers to study the distribution of bioactive compounds used in healthcare. Due to their extensive use, GPN released into the environment would probably pose a threat to living organisms and ultimately to human health. Their accumulation in the aquatic environment creates problems to aquatic habitats as well as to food chains. Until now the potential toxic effects of GPN are not properly understood. Despite agglomeration and long persistence in the environment, GPNs are able to cross the cellular barriers successfully, entered into the cells, and are able to interact with almost all the cellular sites including the plasma membrane, cytoplasmic organelles, and nucleus. Their interaction with DNA creates more potential threats to both the genome and epigenome. In this brief review, we focused on fish, mainly zebrafish (Danio rerio), as a potential target animal of GPN toxicity in the aquatic ecosystem.

Health and Racial Disparity in Breast Cancer.

Breast cancer is the most common noncutaneous malignancy and the second most lethal form of cancer among women in the United States. It currently affects more than one in ten women worldwide. The chance for a female to be diagnosed with breast cancer during her lifetime has significantly increased from 1 in 11 women in 1975 to 1 in 8 women (Altekruse, SEER Cancer Statistics Review, 1975-2007. National Cancer Institute, Bethesda, 2010). This chance for a female of being diagnosed with cancer generally increases with age (Howlader et al, SEER Cancer Statistics Review, 1975-2010. National Cancer Institute, Bethesda, 2013). Fortunately, the mortality rate from breast cancer has decreased in recent years due to increased emphasis on early detection and more effective treatments in the White population. Although the mortality rates have declined in some ethnic populations, the overall cancer incidence among African American and Hispanic population has continued to grow. The goal of the work presented in this book chapter is to highlight similarities and differences in breast cancer morbidity and mortality rates among non-Hispanic white and non-Hispanic black populations. This book chapter also provides an overview of breast cancer, racial/ethnic disparities in breast cancer, breast cancer incidence and mortality rate linked to hereditary, major risk factors of breast cancer among minority population, breast cancer treatment, and health disparity. A considerable amount of breast cancer treatment research have been conducted, but with limited success for African Americans compared to other ethnic groups. Therefore, new strategies and approaches are needed to promote breast cancer prevention, improve survival rates, reduce breast cancer mortality, and ultimately improve the health outcomes of racial/ethnic minorities. In addition, it is vital that leaders and medical professionals from minority population groups be represented in decision-making in research so that racial disparity in breast cancer can be well-studied, fully addressed, and ultimately eliminated in breast cancer.

Toxicity of As in Crassostrea virginica (Gmelin, 1791) from the Northern Gulf of Mexico at the presence of Zn and its antioxidant defense mechanisms.

Reactive oxygen species (ROS) such as the free radicals (e.g. hydroxyl, nitric acid, superoxide) cause damage to lipids, proteins and DNA. Increased production of ROS occurs from pollution. Process of removal or neutralization of ROS is achieved through antioxidants enzyme defense systems and provide homeostasis within biological systems. Aerobic organisms have complex antioxidant systems using enzymatic and non-enzymatic antioxidants to prevent overproduction of ROS. This study examined the toxic effects of arsenic and zinc on Eastern oysters, their interaction and resulting enzymatic responses. Cellular damage as indicated with lipid peroxidation and antioxidant defensive enzyme activities (superoxide dismutase, SOD; glutathione peroxidase, GPX and catalase, CAT) were measured in the hepatopancreas of Eastern oysters exposed to single and combined treatments of arsenic and zinc for 30 days. The results showed either arsenic or zinc exposure significantly increased the lipid peroxidation and triggered antioxidant defenses. Activities of antioxidant enzymes (SOD, GPX and CAT) were markedly elevated upon expose of As or Zn. However, at the presence of Zn, As toxicity expressed as lipid oxidation significantly decreased as well as accordingly decreased activities of antioxidant enzymes. This revealed that the presence of Zn showed a significantly antagonistic effect on arsenic toxicity in Eastern oysters from Northern Gulf of Mexico.

State of the science review of the health effects of inorganic arsenic: Perspectives for future research.

Human exposure to inorganic arsenic (iAs) is a global health issue. Although there is strong evidence for iAs-induced toxicity at higher levels of exposure, many epidemiological studies evaluating its effects at low exposure levels have reported mixed results. We comprehensively reviewed the literature and evaluated the scientific knowledge on human exposure to arsenic, mechanisms of action, systemic and carcinogenic effects, risk characterization, and regulatory guidelines. We identified areas where additional research is needed. These priority areas include: (1) further development of animal models of iAs carcinogenicity to identify molecular events involved in iAs carcinogenicity; (2) characterization of underlying mechanisms of iAs toxicity; (3) assessment of gender-specific susceptibilities and other factors that modulate arsenic metabolism; (4) sufficiently powered epidemiological studies to ascertain relationship between iAs exposure and reproductive/developmental effects; (5) evaluation of genetic/epigenetic determinants of iAs effects in children; and (6) epidemiological studies of people chronically exposed to low iAs concentrations.

Quantification of MicroRNAs by Coupling Cyclic Enzymatic Amplification with Microfluidic Voltage-Assisted Liquid Desorption Electrospray Ionization Mass Spectrometry.

Quantitative assay of microRNAs (miRNAs) with mass spectrometric detection currently suffers from two major disadvantages, i.e., being insufficient in sensitivity and requiring an extraction or chromatographic separation prior to MS detection. In this work, we developed a facile and sensitive assay of targeted miRNAs based on the combination of cyclic enzymatic amplification (CEA) with microfluidic voltage-assisted liquid desorption electrospray ionization tandem mass spectrometry (VAL-DESI-MS/MS). The single-stranded DNA (ssDNA) probe was designed to have a sequence complementary to the miRNA target with an extension of a two-base nucleotide fragment (i.e., CpC) at the 3'-position as MS signal reporter, thus being easy to prepare and high in stability. In the proposed CEA-VAL-DESI-MS/MS assay, an ssDNA probe was added to a sample solution, forming a DNA-miRNA hybrid. Duplex-specific nuclease (DSN) was then added to cleave specifically the DNA probe in the heteroduplex strands. As the hybridization-cleavage cycle repeated itself for many rounds, a large quantity of CpC molecules was produced that was quantified by VAL-DESI-MS/MS with accuracy and specificity. miRNA-21 was tested as the model target. The assay had a linear calibration equation in the range from 2.5 pM to 1.0 nM with a limit of detection of 0.25 pM. Determination of miRNA-21 in cellular samples was demonstrated. miRNA-21 was found to be 95.3 ± 13.95 amol ( n = 3) in 100 mouse peritoneal macrophages with a recovery of 94.2 ± 2.6% ( n = 3). Interestingly, analysis of exosomes secreted from these cells revealed that exposure of the cells to chemical stimuli caused a 3-fold increase in exosomal level of miRNA-21. The results suggest that the proposed assay may provide an accurate and cost-effective means for quantification of targeted miRNAs in biomedical samples.

Low doses of multi-walled carbon nanotubes elicit hepatotoxicity in rats with markers of oxidative stress and induction of pro-inflammatory cytokines.

The investigation into the potential health risks associated with the use of engineered nanoparticles is a major scientific interest in recent years. The present study elucidated the involvement of pro-inflammatory cytokines, cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) in carboxylated multi-walled carbon nanotubes (MWCNTs)-induced hepatotoxicity. Pubertal rats were exposed to purified MWCNTs at 0, 0.25, 0.50, 0.75 and 1.0 mg/kg for 5 consecutive days. Results indicated that exposure to MWCNTs caused liver damage evidenced by significant elevation in serum activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma glutamyl transferase (GGT) when compared with control. Moreover, MWCNTs significantly decreased superoxide dismutase (SOD) and glutathione S-transferase (GST) activities as well as glutathione level whereas it significantly increased catalase (CAT) and glutathione peroxidase (GPx) activities in liver of the treated rats. Moreover, the dose-dependent increase in hepatic hydrogen peroxide (H2O2) and lipid peroxidation levels were accompanied by marked increase in micronucleated polychromatic erythrocytes (MNPCE) in the MWCNTs-treated rats. Administration of MWCNTs significantly increased serum concentrations of pro-inflammatory cytokines namely interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in the treated rats. Immunohistochemical analysis showed significantly increased COX-2 and iNOS protein expressions in the liver of MWCNTs-treated rats. In conclusion, carboxylated MWCNTs induces hepatic damage via disruption of antioxidant defense systems, promotion of pro-inflammatory cytokines generation and expression of COX-2 and i-NOS in rats.

Trisenox induces cytotoxicity through phosphorylation of mitogen-activated protein kinase molecules in acute leukemia cells.

Trisenox (TX) has been used successfully for the treatment of acute promyelocytic leukemia (APL) patients. TX-induced cytotoxicity in APL cells remains poorly understood. In this study, we investigated the molecular mechanism of TX cytotoxicity using APL cell lines. We assessed TX toxicity by quantitatively measuring lactate dehydrogenase levels. Inhibition of cell cycle progression was assessed by confocal microscopy of Ki-67 expression. Apoptosis was evaluated by Western blot analysis of apoptotic proteins expression, immunocytochemistry, and confocal imaging of annexin V and propidium iodide. Mitogen-activated protein kinase (MAPK) signaling cascade was analyzed by Western blot analysis and inhibitor-based experiments with APL cells. We found that TX-induced cytotoxicity inhibited APL cell cycle progression. TX also induced significant (P < 0.05) changes in the expression levels of apoptotic molecules and activated the phosphorylation of MAPK signaling pathways in APL cells. Understanding the mechanism of TX cytotoxicity would be helpful in the design of new APL drugs.

Toxicity implications for early life stage Japanese medaka (Oryzias latipes) exposed to oxyfluorfen.

We investigated the potential toxic effects of Oxyfluorfen (OXY), an herbicide used in agriculture, on the embryo-larval development of Japanese medaka fish (Oryzias latipes). Embryos (1-day postfertilization) and larvae (2-day posthatch) were exposed to OXY (0.5-8 mg/L) for 96 h and evaluated for mortality and hatching on embryos, and the mortality and growth on larvae during depuration. It was observed that the embryo-mortality was inconsistently altered by OXY; only the 2 mg/L group showed significant reduction on embryo survivability. However, larval-mortality was concentration-dependent and OXY exposure induced scoliosis-like phenotypic features in the surviving larvae; the calculated LC50 was 5.238 mg/L. Our data further indicated that larval skeleton, both axial and appendicular, was the potential target site of OXY. Skeletal growth in larvae exposed to 2 mg/L was inhibited significantly until 1 week of depuration with regard to the linear lengths of neurocranium, Meckel's cartilage, caudal vertebrae (first 10) in the axial skeletons, and pectoral fin and urostyle in the appendicular skeletons. Moreover, the total protein content remained unaltered by OXY after 96 h exposure; while the RNA concentration was reduced significantly in larvae exposed to 2 mg/L. Expression analysis of several genes by quantitative real-time RT-PCR (RT-qPCR) showed significant upregulation of zic5, a zinc-finger type transcription regulator, at the transcription level. This study indicated that the scoliosis induced by OXY in Japanese medaka larvae was the result of stunted skeletal growth, probably because of deregulation of zinc-finger type transcription regulators, at the genomic level.

Therapeutic Mechanisms of Vernonia amygdalina Delile in the Treatment of Prostate Cancer.

Prostate cancer patients have been suffering from limited treatment options due to late diagnosis, poor drug tolerance, and multi-drug resistance to almost all the current drug treatments. Therefore, it is important to seek a new alternative therapeutic medicine that can effectively prevent the disease and even eradicate the progression and metastasis of prostate cancer. Vernonia amygdalina Delile (VAD) is a common edible vegetable in Cameroon that has been used as a traditional medicine for some human diseases. However, to the best of our knowledge, no previous reports have explored its therapeutic efficacy against human prostate cancer. The objective of the present study was to assess the anticancer activities of VAD methanolic extracts in the prevention and treatment of prostate cancer using human androgen-independent prostate cancer (PC-3) cells as a test model. To achieve our objective, PC-3 cells were treated with various doses of VAD for 48 h. Data generated from the trypan blue test and MTT assay demonstrated that VAD extracts exhibited significant growth-inhibitory effects on PC-3 cells. Collectively, we established for the first time the antiproliferative effects of VAD on PC-3 cells, with an IC50 value of about 196.6 µg/mL. Further experiments, including cell morphology, lipid peroxidation and comet assays, and apoptosis analysis showed that VAD caused growth-inhibitory effects on PC-3 cells through the induction of cell growth arrest, DNA damage, apoptosis, and necrosis in vitro and may provide protection from oxidative stress diseases as a result of its high antioxidant content. These results provide useful data on the anticancer activities of VAD for prostate cancer and demonstrate the novel possibilities of this medicinal plant for developing prostate cancer therapies.

Cytogenetic evaluation of functionalized single-walled carbon nanotube in mice bone marrow cells.

With their unique structure and physicochemical properties, single\-walled carbon nanotubes (SWCNTs) have many potential new applications in medicine and industry. However, there is lack of detailed information concerning their impact on human health and the environment. The aim of this study was to assess the effects, after intraperitoneal injection of functionalized SWCNTs (f-SWCNT) on the induction of reactive oxygen species (ROS), frequency of structural chromosomal aberrations (SCA), frequency of micronuclei induction, mitotic index, and DNA damage in Swiss-Webster mice. Three doses of f-SWCNTs (0.25, 0.5, and 0.75 mg/kg) and two controls (negative and positive) were administered to mice, once a day for 5 days. Bone marrow and peripheral blood samples were collected 24 h after the last treatment following standard protocols. F-SWCNT exposure significantly enhanced ROS, increased (p < 0.05) the number of SCA and the frequency of micronucleated cells, increased DNA damage, and decreased the mitotic index in exposed groups compared to negative control. The scientific findings reported here suggest that purified f-SWCNT have the potential to induce oxidative stress mediated genotoxicity in Swiss-Webster mice at higher level of exposure. Further characterization of their systemic toxicity, genotoxicity, and carcinogenicity is also essential. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1091-1102, 2016.