Synthesis and evaluation of inhibitors against vitamin D3 and all-trans retinoic acid metabolising enzymes as potential therapy for androgen-independent prostate cancer

1alpha25-Dihydroxyvitamin D3 (1alpha,25-(OH)2-D 3) and all-trans retinoic acid (ATRAA) have differentiating and anti-proliferative effects on prostate cancer cells. However, the use of 1alpha,25-(OH)2-D3 and ATRA is limited by the induction of the cytochrome P450 enzymes. A drug which can prolong the action of 1alpha,25-(OH) 2-D3 or ATRA by inhibiting the P450 enzymes could have potential use in the treatment of AIPC. Three series of novel compounds were synthesised in an attempt to probe for the key binding residues in the enzymes. The preparation of the rat kidney mitochondria and rat liver microsome enzymes were described herein to study the inhibition of the 25-hydroxyvitamin D 3 and ATRA metabolism respectively using the synthesised compounds. In addition, cancer cell-lines (MCF-7 and DU-145) were also used to study the inhibition of the 25-hydroxyvitamin D3 and ATRA metabolism using the synthesised compounds. Reverse-transcriptase-polymerase chain reaction (RT-PCR) analysis was carried out to demonstrate the presence of CYP24 and CYP26 mRNA in the cancer cell-lines. Some of the synthesised compounds described herein show improved activities compared with ketoconazole and/or liarozole in these in vitro assays. Molecular docking studies using the homology model of CYP26 was carried out to investigate the binding of the substrate, ATRA and the synthesised compounds at the active site. Furthermore, the anti-proliferative effects of some synthesised compounds, both alone and in combination with 1alpha25-(OH)2-D3 in human prostate cancer cells (DU-145 and PC-3) were examined. The effects of ketoconazole and one of the synthesised compounds were further investigated to examine their effects, both alone and in combination with 1alpha25-(OH)2-D 3 on the vitamin D3 target genes in DU-145 and PC-3 by real-time quantitative RT-PCR

SLC transporters as therapeutic targets: Emerging opportunities

Solute carrier (SLC) transporters-a family of more than 300 membrane-bound proteins that facilitate the transport of a wide array of substrates across biological membranes-have important roles in physiological processes ranging from the cellular uptake of nutrients to the absorption of drugs and other xenobiotics. Several classes of marketed drugs target well-known SLC transporters, such as neurotransmitter transporters, and human genetic studies have provided powerful insight into the roles of more-recently characterized SLC transporters in both rare and common diseases, indicating a wealth of new therapeutic opportunities. This Review summarizes knowledge on the roles of SLC transporters in human disease, describes strategies to target such transporters, and highlights current and investigational drugs that modulate SLC transporters, as well as promising drug targets

Application of red pitaya powder as a natural food colourant in fruit pastille

Background: Confectionary products meet the important consumers’ need states of fun and enjoyment, especially among children. Synthetic colourant had been applied as a colouring agent in confectionery products for decades, however various adverse health effects have been reported after consumption. Hence, usage of natural colourant has increased enormously as it confers functional and nutraceutical benefits. Red pitaya, a common and popular fruit cultivated in South-east Asian countries. It is rich betacyanin content that gives the fruit a red-violet colour. Hence, red pitaya is a potential source of natural colorant as an alternative to the synthetic colorant.Objective: This research was aimed to produce fruit pastille with red pitaya powder applied as a natural colourant.Method: Production of red pitaya powder was achieved through spray drying process. Fruit pastille was prepared and subjected to antioxidant, stability and sensory analysis.Results: The Physicochemical study showed that pastille incorporated with red pitaya powder exhibited significantly (p<0.05) higher antioxidant properties than the blank pastille (control). An eight weeks storage stability study revealed that betacyanin content of pastille incorporated with pitaya powder remained stable for the first four weeks of storage. Besides, no significant change was observed in redness (a*) of pastille throughout the storage study. Sensory study was carried out to assess the consumer preference on pastille incorporated with pitaya powder and synthetic colourant. Colour attribute of pastille incorporated with red pitaya powder has gained significantly (p<0.05) higher liking that the one added with synthetic colour.Conclusion: Red pitaya powder could be a potential natural colourant for gummy confectionery

GenEpi: gene-based epistasis discovery using machine learning.

BackgroundGenome-wide association studies (GWAS) provide a powerful means to identify associations between genetic variants and phenotypes. However, GWAS techniques for detecting epistasis, the interactions between genetic variants associated with phenotypes, are still limited. We believe that developing an efficient and effective GWAS method to detect epistasis will be a key for discovering sophisticated pathogenesis, which is especially important for complex diseases such as Alzheimer's disease (AD).ResultsIn this regard, this study presents GenEpi, a computational package to uncover epistasis associated with phenotypes by the proposed machine learning approach. GenEpi identifies both within-gene and cross-gene epistasis through a two-stage modeling workflow. In both stages, GenEpi adopts two-element combinatorial encoding when producing features and constructs the prediction models by L1-regularized regression with stability selection. The simulated data showed that GenEpi outperforms other widely-used methods on detecting the ground-truth epistasis. As real data is concerned, this study uses AD as an example to reveal the capability of GenEpi in finding disease-related variants and variant interactions that show both biological meanings and predictive power.ConclusionsThe results on simulation data and AD demonstrated that GenEpi has the ability to detect the epistasis associated with phenotypes effectively and efficiently. The released package can be generalized to largely facilitate the studies of many complex diseases in the near future

Organic cation transporter 1 (OCT1) modulates multiple cardiometabolic traits through effects on hepatic thiamine content.

A constellation of metabolic disorders, including obesity, dysregulated lipids, and elevations in blood glucose levels, has been associated with cardiovascular disease and diabetes. Analysis of data from recently published genome-wide association studies (GWAS) demonstrated that reduced-function polymorphisms in the organic cation transporter, OCT1 (SLC22A1), are significantly associated with higher total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride (TG) levels and an increased risk for type 2 diabetes mellitus, yet the mechanism linking OCT1 to these metabolic traits remains puzzling. Here, we show that OCT1, widely characterized as a drug transporter, plays a key role in modulating hepatic glucose and lipid metabolism, potentially by mediating thiamine (vitamin B1) uptake and hence its levels in the liver. Deletion of Oct1 in mice resulted in reduced activity of thiamine-dependent enzymes, including pyruvate dehydrogenase (PDH), which disrupted the hepatic glucose-fatty acid cycle and shifted the source of energy production from glucose to fatty acids, leading to a reduction in glucose utilization, increased gluconeogenesis, and altered lipid metabolism. In turn, these effects resulted in increased total body adiposity and systemic levels of glucose and lipids. Importantly, wild-type mice on thiamine deficient diets (TDs) exhibited impaired glucose metabolism that phenocopied Oct1 deficient mice. Collectively, our study reveals a critical role of hepatic thiamine deficiency through OCT1 deficiency in promoting the metabolic inflexibility that leads to the pathogenesis of cardiometabolic disease

Unraveling the functional role of the orphan solute carrier, SLC22A24 in the transport of steroid conjugates through metabolomic and genome-wide association studies.

Variation in steroid hormone levels has wide implications for health and disease. The genes encoding the proteins involved in steroid disposition represent key determinants of interindividual variation in steroid levels and ultimately, their effects. Beginning with metabolomic data from genome-wide association studies (GWAS), we observed that genetic variants in the orphan transporter, SLC22A24 were significantly associated with levels of androsterone glucuronide and etiocholanolone glucuronide (sentinel SNPs p-value &lt;1x10-30). In cells over-expressing human or various mammalian orthologs of SLC22A24, we showed that steroid conjugates and bile acids were substrates of the transporter. Phylogenetic, genomic, and transcriptomic analyses suggested that SLC22A24 has a specialized role in the kidney and appears to function in the reabsorption of organic anions, and in particular, anionic steroids. Phenome-wide analysis showed that functional variants of SLC22A24 are associated with human disease such as cardiovascular diseases and acne, which have been linked to dysregulated steroid metabolism. Collectively, these functional genomic studies reveal a previously uncharacterized protein involved in steroid homeostasis, opening up new possibilities for SLC22A24 as a pharmacological target for regulating steroid levels