In vitro study of Nigella sativa and thymoquinone activity on endothelial activation and monocyte adhesion.

INTRODUCTION: Thymoquinone (TQ) is one of the bioactive compounds in Nigella sativa (NS). Also known as black seeds/cumin, it has been postulated to possess anti-atherogenic properties. However, research on the effects of NS oil (NSO) and TQ on atherogenesis remain scarce. The aim of this study is to determine gene and protein expression of Intercellular Adhesion Molecule-1 (ICAM-1), Vascular Cell Adhesion Molecule-1 (VCAM-1), and Endothelial-eukocyte adhesion molecule (E-selectin) in Human Coronary Artery Endothelial Cells (HCAECs). METHODS: HCAECs were stimulated for 24 hours (h) with 200 µg/ml of Lipopolysaccharides (LPS) and different concentrations of NSO (55, 110, 220, 440 µg/ml) or TQ (4.5, 9.0, 18.0, 36.0 µm). The effects of NSO and TQ on gene and protein expressions were measured using multiplex gene assay and ELISA assay, respectively. Rose Bengal assay was used to analyse monocyte binding activity. RESULTS: NSO and TQ significantly reduced ICAM-1 and VCAM-1 gene and protein expressions. TQ showed significant reduction activity of the biomarkers in dose dependent manner. HCAECs pre-treated with NSO and TQ for 24 h significantly lowered monocytes adherence compared to non-treated HCAECs. CONCLUSIONS: NSO and TQ supplementation have anti-atherogenic properties and inhibit monocytes' adherence to HCAECs via down-regulation of ICAM-1 expression. NSO could potentially be incorporated in standard treatment regimens to prevent atherosclerosis and its related complications.

Osteoblast Demineralization Induced by Oxidized High-Density Lipoprotein via the Inflammatory Pathway Is Suppressed by Adiponectin.

Low mineralization activity by human osteoblast cells (HOBs) indicates abnormal bone remodeling that potentially leads to osteoporosis. Oxidation, the most prominent form of high-density lipoprotein (HDL) modification, is suggested to affect bone mineralization through the inflammatory pathway. Adiponectin, which possesses anti-inflammatory activity, is postulated to have the ability to suppress the detrimental effects of oxidized HDL (oxHDL). This study aimed to investigate the effects of HDL before and after oxidation on markers of mineralization and inflammation. The protective effects of adiponectin on demineralization and inflammation induced by oxHDL were also investigated. OxHDL at 100 µg/mL protein had the highest inhibitory effect on mineralization, followed by lower calcium incorporation. OxHDL also had significantly lower expression of a mineralization marker (COL1A2) and higher expression of inflammatory markers (IL-6, TNF-α, and RELA proto-oncogene, NF-κß (p65)) compared to the unstimulated control group. These findings suggest that oxHDL reduces the mineralization activity of HOBs by increasing the expression of inflammatory markers. Interestingly, co-incubation of adiponectin and oxHDL in HOBs resulted in higher expression of mineralization markers (ALPL, COL1A2, BGLAP, and RUNX2) and significantly reduced all targeted inflammatory markers compared to the oxHDL groups. On the contrary, HDL increased the expression of mineralization markers (COL1A2 and STAT-3) and exhibited lower expression of inflammatory cytokines (IL-6 and TNF-α), proving the protective effect of HDL beyond the reverse cholesterol transport activity.

DNA methylation profiling revealed promoter hypermethylation-induced silencing of p16, DDAH2 and DUSP1 in primary oral squamous cell carcinoma.

BACKGROUND: Hypermethylation in promoter regions of genes might lead to altered gene functions and result in malignant cellular transformation. Thus, biomarker identification for hypermethylated genes would be very useful for early diagnosis, prognosis, and therapeutic treatment of oral squamous cell carcinoma (OSCC). The objectives of this study were to screen and validate differentially hypermethylated genes in OSCC and correlate the hypermethylation-induced genes with demographic, clinocopathological characteristics and survival rate of OSCC. METHODS: DNA methylation profiling was utilized to screen the differentially hypermethylated genes in OSCC. Three selected differentially-hypermethylated genes of p16, DDAH2 and DUSP1 were further validated for methylation status and protein expression. The correlation between demographic, clinicopathological characteristics, and survival rate of OSCC patients with hypermethylation of p16, DDAH2 and DUSP1 genes were analysed in the study. RESULTS: Methylation profiling demonstrated 33 promoter hypermethylated genes in OSCC. The differentially-hypermethylated genes of p16, DDAH2 and DUSP1 revealed positivity of 78%, 80% and 88% in methylation-specific polymerase chain reaction and 24% and 22% of immunoreactivity in DDAH2 and DUSP1 genes, respectively. Promoter hypermethylation of p16 gene was found significantly associated with tumour site of buccal, gum, tongue and lip (P=0.001). In addition, DDAH2 methylation level was correlated significantly with patients' age (P=0.050). In this study, overall five-year survival rate was 38.1% for OSCC patients and was influenced by sex difference. CONCLUSIONS: The study has identified 33 promoter hypermethylated genes that were significantly silenced in OSCC, which might be involved in an important mechanism in oral carcinogenesis. Our approaches revealed signature candidates of differentially hypermethylated genes of DDAH2 and DUSP1 which can be further developed as potential biomarkers for OSCC as diagnostic, prognostic and therapeutic targets in the future.

Induction of a single dose of streptozotocin (50 mg) in rat model causes insulin resistance with type 2 diabetes mellitus.

Streptozotocin (STZ) is a broad-spectrum antibiotic that is toxic to the insulin-producing beta cells of the pancreatic islets. STZ is currently used clinically for the treatment of metastatic islet cell carcinoma of the pancreas and the induction of diabetes mellitus (DM) in rodents. So far, there has been no previous research to show that STZ injection in rodents causes insulin resistance in type 2 diabetes mellitus (T2DM). The purpose of this study was to determine if rats (Sprague-Dawley) developed type 2 diabetes mellitus (insulin resistance) after 72 h of intraperitoneal administration of 50 mg/kg STZ. Rats with fasting blood glucose levels above 11.0 mM, 72 h post-STZ induction, were used. The body weight and plasma glucose levels were measured every week throughout the 60-day treatment period. The plasma, liver, kidney, pancreas, and smooth muscle cells were harvested for antioxidant, biochemical analysis, histology, and gene expression studies. The results revealed that STZ was able to destroy the pancreatic insulin-producing beta cell, as evidenced by an increase in plasma glucose level, insulin resistance, and oxidative stress. Biochemical investigation indicates that STZ can generate diabetes complications through hepatocellular damage, elevated HbA1c, kidney damage, hyperlipidemia, cardiovascular damage, and impairment of the insulin-signaling pathway.

Phytoestrogens by inhibiting the non-classical oestrogen receptor, overcome the adverse effect of bisphenol A on hFOB 1.19 cells.

OBJECTIVES: Since bisphenol A (BPA) induces bone loss and phytoestrogens enhance the osteoblastogenesis by binding to the non-classical and classical oestrogen receptors, respectively, the present study was aimed to observe the osteoprotective effect of phytoestrogens on BPA-induced osteoblasts in hFOB 1.19 cells. MATERIALS AND METHODS: All groups of hFOB 1.19 cells were induced with 12.5 µg/ml of BPA except the control (Ctrl) group. Meanwhile, treated groups received phytoestrogens; Daidzein (Dz), Genistein (Gt), Equol (Eq) and 17ß-oestradiol (Est) in different concentrations for 24 hr duration. RESULTS: We found that the protein expression of non-classical oestrogen-related receptor (ERRG) was highly expressed in BPA group, whereas classical oestrogen receptor alpha (ERα) and oestrogen receptor beta (ERß) were relatively increased with phytoestrogens treatment under BPA exposure. The dense actin cytoskeletal filaments were also observed. qRT-PCR showed up-regulation of mitogen-activated protein kinase 3 (MAPK3) and G protein-coupled receptor 30 (GPR30) expressions; significant down-regulation of ERRG and up-regulation of ERα and ERß were observed in phytoestrogens-treated cells, which was supported by the increased expressions of oestrogen receptor 1 (ESR1) and oestrogen receptor 2 (ESR2). CONCLUSION: Phytoestrogens improved the deteriorative effect of BPA via down-regulation of ERRG in hFOB 1.19 cells. This study showed that the efficacy of consumption of phytoestrogens in rendering them as potential therapeutic strategy in combating the adverse bone effects of BPA.

Inflammation and Vascular Calcification Causing Effects of Oxidized HDL are Attenuated by Adiponectin in Human Vascular Smooth Muscle Cells.

The role of oxidized high- density lipoprotein (oxHDL) and the protective effects of adiponectin in terms of vascular calcification is not well-established. This study was conducted to investigate the effects of oxHDL with regard to inflammation and vascular calcification and to determine the protective role of adiponectin in attenuating the detrimental effects of oxHDL. Cell viability, mineralization, and calcification assays were conducted to optimize the concentration of oxHDL. Then, human vascular smooth muscle cells (HAoVSMCs) were incubated with ß-glycerophosphate, HDL, oxHDL, adiponectin, or the combination of oxHDL with adiponectin for 24 h. Protein expression of IL-6, TNF-α, osterix, RUNX2, ALP, type 1 collagen, osteopontin, osteocalcin, WNT-5a, NF-ĸß(p65), cAMP and STAT-3 were measured by ELISA kits. OxHDL induced vascular calcification by promoting the formation of mineralization nodules and calcium deposits in HAoVSMCs. This was accompanied by an increased secretion of IL-6, osterix, WNT-5a and NF-Ä¸ß (p65). Interestingly, these detrimental effects of oxHDL were suppressed by adiponectin. Besides, incubation of adiponectin alone on HAoVSMCs showed a reduction of inflammatory cytokines, osteoblastic markers (RUNX2, osterix and osteopontin), WNT-5a and NF-Ä¸ß (p65). This study exhibits the ability of oxHDL in inducing inflammation and vascular calcification and these detrimental effects of oxHDL can be attenuated by adiponectin.

Bisphenol A exposure disturbs the bone metabolism: An evolving interest towards an old culprit.

Bisphenol A (BPA) (2,2,-bis (hydroxyphenyl) propane), a well-known endocrine disruptor (ED), is the exogenous chemical that mimic the natural endogenous hormone like oestrogen. Due to its extensive exposure to humans, BPA is considered to be a major toxicological agent for general population. Environmental exposure of BPA results in adverse health outcomes including bone loss. BPA disturbs the bone health by decreasing the plasma calcium level and inhibiting the calcitonin secretion. BPA also stimulated differentiation and induced apoptosis in human osteoblasts and osteoclasts. However, little is known about the underlying mechanisms of the untoward effect of BPA against bone metabolism. The present review gives an overview on the possible mechanisms of BPA towards bone loss. The previous literature shows that BPA exerts its toxic effect on bone cells by binding to the oestrogen related receptor-gamma (ERγ), reducing the bone morphogenic protein-2 (BMP-2) and alkaline phosphatase (ALP) activities. BPA interrupts the bone metabolism via RANKL, apoptosis and Wnt/ß-catenin signaling pathways. It is, however, still debated on the exact underlying mechanism of BPA against bone health. We summarised the molecular evidences with possible mechanisms of BPA, an old environmental culprit, in bone loss and enlightened the underlying understanding of adverse action of BPA in the society.

Employing different types of phytoestrogens improve bone mineralization in bisphenol A stimulated osteoblast.

AIMS: Phytoestrogens and xenoestrogens act as agonists/antagonists in bone formation and differentiation. Strong bones are depending of the ability of osteoblasts to form new tissue and to mineralize the newly formed tissue. Dysfunctional or loss of mineralization leads to weak bone and increased fracture risk. In this study, we reported the effect of different types of phytoestrogens (daidzein, genistein and equol) on mineralization in hFOB 1.19 cells stimulated with bisphenol A (BPA). MAIN METHODS: Cell mineralization capacity of phytoestrogens was investigated by evaluating calcium, phosphate content and alkaline phosphatase activity. Bone related markers, osteocalcin and osteonectin, responsible in maintaining mineralization were also measured. KEY FINDINGS: BPA is significantly interfering with bone mineralization in hFOB 1.19 cells. However, the enhanced mineralization efficacy of daidzein and genistein (particularly at a dose of 5 and 40 µg/mL, respectively) was evidenced by increasing calcium and phosphate content, higher ALP activity, compared to the untreated BPA group. The quantitative analyses were confirmed through morphological findings. Osteocalcin and osteonectin levels were increased in phytoestrogens-treated cells. These findings revealed the potential effect of phytoestrogens in reverting the demineralization process due to BPA exposure in hFOB 1.19 cells. SIGNIFICANCE: We found that osteoblast differentiation and mineralization were maintained following treatment with phytoestrogens under BPA exposure.

Cytoskeletal alterations in different developmental stages of in vivo cryopreserved preimplantation murine embryos.

BACKGROUND: This study aimed to investigate the effects of vitrification and slow freezing on actin, tubulin, and nuclei of in vivo preimplantation murine embryos at various developmental stages using a Confocal Laser Scanning Microscope (CLSM). MATERIAL/METHODS: Fifty female mice, aged 4-6 weeks, were used in this study. Animals were superovulated, cohabitated overnight, and sacrificed. Fallopian tubes were excised and flushed. Embryos at the 2-cell stage were collected and cultured to obtain 4- and 8-cell stages before being cryopreserved using vitrification and slow freezing. Fixed embryos were stained with fluorescence-labelled antibodies against actin and tubulin, as well as DAPI for staining the nucleus. Labelled embryos were scanned using CLSM and images were analyzed with Q-Win software V3. RESULTS: The fluorescence intensity of both vitrified and slow-frozen embryos was significantly lower for tubulin, actin, and nucleus as compared to non-cryopreserved embryos (p<0.001). Intensities of tubulin, actin, and nucleus in each stage were also decreased in vitrified and slow-frozen groups as compared to non-cryopreserved embryos. CONCLUSIONS: Cryopreservation of mouse embryos by slow freezing had a more detrimental effect on the actin, tubulin, and nucleus structure of the embryos compared to vitrification. Vitrification is therefore superior to slow freezing in terms of embryonic cryotolerance.

Human papilloma virus 18 detection in oral squamous cell carcinoma and potentially malignant lesions using saliva samples.

BACKGROUND: Oral cancer has become one of the most prevalent cancers worldwide and human Papillomavirus is one of the risk factors for developing oral cancer. For this study HPV18 was chosen as it is one of the high risk HPV types and may lead to carcinogenesis. However, prevalence of HPV18 infection in Oral Squamous Cell Carcinoma in Malaysia remains unclear. OBJECTIVE: This study aimed to investigate the viral load of HPV18 DNA in OSCC and potentially malignant lesions using saliva samples. MATERIALS AND METHODS: Genomic DNAs of thirty saliva samples of normal subjects and thirty saliva samples compromised of 16 samples from potentially malignant lesions and 14 of OSCC patients were amplified for HPV18 DNA using a nested polymerase chain reaction analysis. All PCR products were then analyzed using the Bioanalyzer to confirm presence of HPV18 DNA. RESULT: From thirty patients examined, only one of 30 (3.3%) cases was found to be positive for HPV18 in this study. CONCLUSION: The finding of this study revealed that there is a low viral detection of HPV18 in Malaysian OSCC by using saliva samples, suggesting that prevalence of HPV18 may not be important in this group of Malaysian OSCC.