15 research outputs found
An investigation into the biochemical, molecular and epigenetic effects of fumonisin B1 in liver (HEPG2) cells.
Ph. D. University of KwaZulu-Natal, Durban 2014.Fumonisins are carcinogenic mycotoxins that occur world wide in maize and maizebased
products intended for human consumption. Consumption of fumonisincontaminated
maize as a staple diet has been associated with oesophageal and liver
cancer in South Africa and China. Fumonisin B1 (FB1) inhibits sphingolipid
biosynthesis and has been implicated in cancer promoting activity in animals and
humans. FB1 disrupts DNA methylation and induces chromatin modifications in
human hepatoma (HepG2) cells. In this study FB1 (IC50=200μM) altered liver enzyme
expression of DNA methyltransferases and demethylases. DNA methyltransferase
activities of DNMT1, 3a and 3b were significantly decreased, whilst both DNA
methylase (MBD2) activity and expression was significantly up-regulated resulting in
global DNA hypomethylation. In addition the histone demethylases, KDM5B and
KDM5C, expression was increased. FACS data confirmed FB1 significantly increased
global DNA hypomethylation – a process that causes chromatin instability. Next the
effect of FB1 on miRNA expression was evaluated; FB1 significantly down-regulated
(11 fold) expression of miR-27b. MiR-27b modulates expression of human
cytochrome P450 (CYP1B1) that catalyzes the metabolic activation of many
procarcinogens. In order to directly assess the effect of miR-27b on CYP1B1 mRNA
levels, liver cells were transfected with the mimic to miR-27b. CYP1B1 mRNA and
protein expression was significantly up-regulated by 1.8- fold and 2.6- fold
respectively. CYP1B1 is post-transcriptionally regulated by miR-27b suggesting that
FB1- induced modulation of miR-27b in hepatic cells may be an additional mode of
hepatic neoplastic transformation. Finally, the effect of FB1 on the apoptotic pathway
in HepG2 cells was investigated using an mRNA expression array panel of pro- and
anti- apoptotic molecules. FB1 significantly increased an AIP family member - BIRC 8/ILP-2 (8-fold) in an apoptosis array. In addition, ILP2 protein expression was
increased (2.3-fold) with a corresponding decrease in Smac/DIABLO protein levels
(1.7-fold). Further analysis showed an FB1 (0μM, 50μM, 100μM, 200μM) dosedependent
increase in BIRC-8/ILP-2 mRNA and protein expression in HepG2 cells.
This data suggests that FB1 modulates apoptosis in a complex dose-dependent
regulation of pro- and anti-apoptotic molecules – and it is not a matter of simply
switching on or off.
In conclusion, the data shows that FB1 possess epigenetic properties by inducing
global DNA hypomethylation, modulating miRNA expression, and increasing
expression of the AIP protein family (BIRC8/ILP-2) that may lead to liver
tumourigenesis
Induction of Caspase-Mediated Apoptosis in HepG2 Liver Carcinoma Cells Using Mutagen–Antioxidant Conjugated Self-Assembled Novel Carbazole Nanoparticles and In Silico Modeling Studies
In this study, novel self-assembled carbazole-thiooctanoic acid nanoparticles (CTNs) were synthesized from amino carbazole (a mutagen) and thiooctanoic acid (an antioxidant). The nanoparticles were characterized using hyperspectral techniques. Then, the antiproliferative potential of CTNs was determined in HepG2 liver carcinoma cells. This study employed a solvent-antisolvent interaction method to synthesize a spherical CTN of size less than 50 nm. Moreover, CT was subsequently capped to gold nanoparticles (AuNPs) in the additional comparative studies. The CT derivative was synthesized from carbazole and lipoic acid by the amide bond formation reaction using a coupling agent. Furthermore, it was characterized using infrared (IR), 1H nuclear magnetic resonance, dynamic light scattering (DLS), and transmission electron microscopy techniques. The CT-capped gold nanoparticles (CTAuNPs) were prepared from CT, chloroauric acid, and NaBH4. The CTAuNPs were characterized using ultraviolet-visible, high-resolution TEM, DLS, and Fourier transform IR techniques. The cytotoxicity and apoptosis-inducing ability of both nanoparticles were determined in HepG2 cells. The results demonstrate that CTNs exhibit antiproliferative activity in the cancerous HepG2 cells. Moreover, molecular docking and molecular dynamics studies were conducted to explore the therapeutic potential of CT against human EGFR suppressor protein to gain more insights into the binding mode of the CT, which may show a significant role in anticancer therapy
Nanobodies Enhancing Cancer Visualization, Diagnosis and Therapeutics
Worldwide, cancer is a serious health concern due to the increasing rates of incidence and mortality. Conventional cancer imaging, diagnosis and treatment practices continue to substantially contribute to the fight against cancer. However, these practices do have some risks, adverse effects and limitations, which can affect patient outcomes. Although antibodies have been developed, successfully used and proven beneficial in various oncology practices, the use of antibodies also comes with certain challenges and limitations (large in size, poor tumor penetration, high immunogenicity and a long half-life). Therefore, it is vital to develop new ways to visualize, diagnose and treat cancer. Nanobodies are novel antigen-binding fragments that possess many advantageous properties (small in size, low immunogenicity and a short half-life). Thus, the use of nanobodies in cancer practices may overcome the challenges experienced with using traditional antibodies. In this review, we discuss (1) the challenges with antibody usage and the superior qualities of nanobodies; (2) the use of antibodies and nanobodies in cancer imaging, diagnosis, drug delivery and therapy (surgery, radiotherapy, chemotherapy and immunotherapy); and (3) the potential improvements in oncology practices due to the use of nanobodies as compared to antibodies
Centella asiatica modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s)
Abstract Background Cancer cachexia is associated with increased pro-inflammatory cytokine levels. Centella asiatica (C. asiatica) possesses antioxidant, anti-inflammatory and anti-tumour potential. We investigated the modulation of antioxidants, cytokines and cell death by C. asiatica ethanolic leaf extract (CLE) in leukaemic THP-1 cells and normal peripheral blood mononuclear cells (PBMC’s). Methods Cytotoxcity of CLE was determined at 24 and 72 h (h). Oxidant scavenging activity of CLE was evaluated using the 2, 2-diphenyl-1 picrylhydrazyl (DPPH) assay. Glutathione (GSH) levels, caspase (−8, −9, −3/7) activities and adenosine triphosphate (ATP) levels (Luminometry) were then assayed. The levels of tumour necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β and IL-10 were also assessed using enzyme-linked immunosorbant assay. Results CLE decreased PBMC viability between 33.25–74.55% (24 h: 0.2–0.8 mg/ml CLE and 72 h: 0.4–0.8 mg/ml CLE) and THP-1 viability by 28.404% (72 h: 0.8 mg/ml CLE) (p < 0.0001). Oxidant scavenging activity was increased by CLE (0.05–0.8 mg/ml) (p < 0.0001). PBMC TNF-α and IL-10 levels were decreased by CLE (0.05–0.8 mg/ml) (p < 0.0001). However, PBMC IL-6 and IL-1β concentrations were increased at 0.05–0.2 mg/ml CLE but decreased at 0.4 mg/ml CLE (p < 0.0001). In THP-1 cells, CLE (0.2–0.8 mg/ml) decreased IL-1β and IL-6 whereas increased IL-10 levels (p < 0.0001). In both cell lines, CLE (0.05–0.2 mg/ml, 24 and 72 h) increased GSH concentrations (p < 0.0001). At 24 h, caspase (−9, −3/7) activities was increased by CLE (0.05–0.8 mg/ml) in PBMC’s whereas decreased by CLE (0.2–0.4 mg/ml) in THP-1 cells (p < 0.0001). At 72 h, CLE (0.05–0.8 mg/ml) decreased caspase (−9, −3/7) activities and ATP levels in both cell lines (p < 0.0001). Conclusion In PBMC’s and THP-1 cells, CLE proved to effectively modulate antioxidant activity, inflammatory cytokines and cell death. In THP-1 cells, CLE decreased pro-inflammatory cytokine levels whereas it increased anti-inflammatory cytokine levels which may alleviate cancer cachexia
Withania somnifera modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s)
CITATION: Naidoo, D. B., et al. 2018. Withania somnifera modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s). BMC Complementary and Alternative Medicine, 18:126, doi:10.1186/s12906-018-2192-y.The original publication is available at https://bmccomplementalternmed.biomedcentral.comBackground: Cancer and inflammation are associated with cachexia. Withania somnifera (W. somnifera) possesses
antioxidant and anti-inflammatory potential. We investigated the potential of an aqueous extract of the root of W.
somnifera (WRE) to modulate cytokines, antioxidants and apoptosis in leukaemic THP-1 cells and peripheral blood
mononuclear cells (PBMC’s).
Methods: Cytotoxcity of WRE was determined at 24 and 72 h (h). Oxidant scavenging activity of WRE was evaluated
(2, 2-diphenyl-1 picrylhydrazyl assay). Glutathione (GSH) levels, caspase (− 8, − 9, − 3/7) activities and adenosine
triphosphate (ATP) levels (Luminometry) were thereafter assayed. Tumour necrosis factor-α (TNF-α), interleukin (IL)-6,
IL-1β and IL-10 levels were also assessed using enzyme-linked immunosorbant assay.
Results: At 24 h, WRE (0.2–0.4 mg/ml) decreased PBMC viability between 20 and 25%, whereas it increased THP-1
viability between 15 and 23% (p < 0.001). At 72 h, WRE increased PBMC viability by 27–39% (0.05, 0.4 mg/ml WRE)
whereas decreased THP-1 viability between 9 and 16% (0.05–0.4 mg/ml WRE) (p < 0.001). Oxidant scavenging activity was
increased by WRE (0.05–0.4 mg/ml, p < 0.0001). PBMC TNF-α and IL-10 levels were decreased by 0.2–0.4 mg/ml WRE,
whereas IL-1β levels were increased by 0.05–0.4 mg/ml WRE (p < 0.0001). In THP-1 cells, WRE (0.05–0.4 mg/ml) decreased
TNF-α, IL-1β and IL-6 levels (p < 0.0001). At 24 h, GSH levels were decreased in PBMC’s, whilst increased in THP-1 cells by
0.2–0.4 mg/ml WRE (p < 0.0001). At 72 h, WRE (0.1–0.4 mg/ml) decreased GSH levels in both cell lines (p < 0.0001). At 24 h,
WRE (0.2–0.4 mg/ml) increased PBMC caspase (-8, -3/7) activities whereas WRE (0.05, 0.1, 0.4 mg/ml) increased THP-1
caspase (-9, -3/7) activities (p < 0.0001). At 72 h, PBMC caspase (-8, -9, -3/7) activities were increased at 0.05–0.1 mg/ml WRE
(p < 0.0001). In THP-1 cells, caspase (-8, -9, -3/7) activities and ATP levels were increased by 0.1–0.2 mg/ml WRE, whereas
decreased by 0.05 and 0.4 mg/ml WRE (72 h, p < 0.0001).
Conclusion: In PBMC’s and THP-1 cells,WRE proved to effectively modulate antioxidant activity, inflammatory cytokines
and cell death. In THP-1 cells, WRE decreased pro-inflammatory cytokine levels, which may alleviate cancer cachexia and
excessive leukaemic cell growth.https://bmccomplementalternmed.biomedcentral.com/articles/10.1186/s12906-018-2192-yPublisher's versio
Centella asiatica modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s)
CITATION: Naidoo, D. B. et al. 2017. Centella asiatica modulates cancer cachexia associated inflammatory cytokines and cell death in leukaemic THP-1 cells and peripheral blood mononuclear cells (PBMC’s). BMC Complementary and Alternative Medicine, 17:377, doi:10.1186/s12906-017-1865-2.The original publication is available at https://bmccomplementalternmed.biomedcentral.comBackground: Cancer cachexia is associated with increased pro-inflammatory cytokine levels. Centella asiatica (C. asiatica) possesses antioxidant, anti-inflammatory and anti-tumour potential. We investigated the modulation of antioxidants, cytokines and cell death by C. asiatica ethanolic leaf extract (CLE) in leukaemic THP-1 cells and normal peripheral blood mononuclear cells (PBMC’s).
Methods: Cytotoxcity of CLE was determined at 24 and 72 h (h). Oxidant scavenging activity of CLE was evaluated using the 2, 2-diphenyl-1 picrylhydrazyl (DPPH) assay. Glutathione (GSH) levels, caspase (−8, −9, −3/7) activities and adenosine triphosphate (ATP) levels (Luminometry) were then assayed. The levels of tumour necrosis factor-α (TNF-α), interleukin (IL)-6, IL-1β and IL-10 were also assessed using enzyme-linked immunosorbant assay.
Results: CLE decreased PBMC viability between 33.25–74.55% (24 h: 0.2–0.8 mg/ml CLE and 72 h: 0.4–0.8 mg/ml CLE) and THP-1 viability by 28.404% (72 h: 0.8 mg/ml CLE) (p < 0.0001). Oxidant scavenging activity was increased by CLE (0.05–0.8 mg/ml) (p < 0.0001). PBMC TNF-α and IL-10 levels were decreased by CLE (0.05–0.8 mg/ml) (p < 0.0001). However, PBMC IL-6 and IL-1β concentrations were increased at 0.05–0.2 mg/ml CLE but decreased at 0.4 mg/ml CLE (p < 0.0001). In THP-1 cells, CLE (0.2–0.8 mg/ml) decreased IL-1β and IL-6 whereas increased IL-10 levels (p < 0.0001). In both cell lines, CLE (0.05–0.2 mg/ml, 24 and 72 h) increased GSH concentrations (p < 0.0001). At 24 h, caspase (−9, −3/7) activities was increased by CLE (0.05–0.8 mg/ml) in PBMC’s whereas decreased by CLE (0.2–0.4 mg/ml) in THP-1 cells (p < 0.0001). At 72 h, CLE (0.05–0.8 mg/ml) decreased caspase (−9, −3/7) activities and ATP levels in both cell lines (p < 0.0001).
Conclusion: In PBMC’s and THP-1 cells, CLE proved to effectively modulate antioxidant activity, inflammatory cytokines and cell death. In THP-1 cells, CLE decreased pro-inflammatory cytokine levels whereas it increased anti-inflammatory cytokine levels which may alleviate cancer cachexia.https://bmccomplementalternmed.biomedcentral.com/articles/10.1186/s12906-017-1865-2Publisher's versio
Pro-inflammatory cytokine levels in HIV infected and uninfected pregnant women with and without pre-eclampsia
DRRMÂ cytokine analysi
Comparative analysis of cytokine perturbations by groups.
<p>Comparative analysis of cytokine perturbations by groups.</p