Phaleria macrocarpa Boerl. (Thymelaeaceae) leaves increase SR-BI expression and reduce cholesterol levels in rats fed a high cholesterol diet
- Authors: Andriani, Yosie , Tengku-Muhammad, Tengku , Mohamad, Habsah , Saidin, Jasnizat , Syamsumir, Desy Fitrya , Chew, Guatsiew , Wahid, Mohd Effendy
- Date: 2015
- Type: Text , Journal article
- Relation: Molecules Vol. 20, no. 3 (2015), p. 4410-4429
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- Description: In vitro and in vivo studies of the activity of Phaleria macrocarpa Boerl (Thymelaeaceae) leaves against the therapeutic target for hypercholesterolemia were done using the HDL receptor (SR-BI) and hypercholesterolemia-induced Sprague Dawley rats. The in vitro study showed that the active fraction (CF6) obtained from the ethyl acetate extract (EMD) and its component 2',6',4-trihydroxy-4'-methoxybenzophenone increased the SR-BI expression by 95% and 60%, respectively. The in vivo study has proven the effect of EMD at 0.5 g/kgbw dosage in reducing the total cholesterol level by 224.9% and increasing the HDL cholesterol level by 157% compared to the cholesterol group. In the toxicity study, serum glutamate oxalate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) activity were observed to be at normal levels. The liver histology also proved no toxicity and abnormalities in any of the treatment groups, so it can be categorized as non-toxic to the rat liver. The findings taken together show that P. macrocarpa leaves are safe and suitable as an alternative control and prevention treatment for hypercholesterolemia in Sprague Dawley rats. ©2015 by the authors; licensee MDPI.
The Zinc Transporter, Slc39a7 (Zip7) Is Implicated in Glycaemic Control in Skeletal Muscle Cells
- Authors: Myers, Stephen , Nield, Alex , Chew, Guatsiew , Myers, Mark
- Date: 2013
- Type: Text , Journal article
- Relation: Plos One Vol. 8, no. 11 (November 2013 2013), p. 15
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- Description: Dysfunctional zinc signaling is implicated in disease processes including cardiovascular disease, Alzheimer's disease and diabetes. Of the twenty-four mammalian zinc transporters, ZIP7 has been identified as an important mediator of the 'zinc wave' and in cellular signaling. Utilizing siRNA targeting Zip7 mRNA we have identified that Zip7 regulates glucose metabolism in skeletal muscle cells. An siRNA targeting Zip7 mRNA down regulated Zip7 mRNA 4.6-fold (p = 0.0006) when compared to a scramble control. This was concomitant with a reduction in the expression of genes involved in glucose metabolism including Agl, Dlst, Galm, Gbe1, Idh3g, Pck2, Pgam2, Pgm2, Phkb, Pygm, Tpi1, Gusb and Glut4. Glut4 protein expression was also reduced and insulin-stimulated glycogen synthesis was decreased. This was associated with a reduction in the mRNA expression of Insr, Irs1 and Irs2, and the phosphorylation of Akt. These studies provide a novel role for Zip7 in glucose metabolism in skeletal muscle and highlight the importance of this transporter in contributing to glycaemic control in this tissue.
Interleukin-6 inhibition of peroxisome proliferator-activated receptor alpha expression is mediated by JAK2- and PI3K-induced STAT1/3 in HepG2 hepatocyte cells
- Authors: Chew, Guatsiew , Myers, Stephen , Shu-Chien, A. C. , Muhammad, Tengku
- Date: 2014
- Type: Text , Journal article
- Relation: Molecular and Cellular Biochemistry Vol. 388, no. 1-2 (2014), p. 25-37
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- Description: Interleukin-6 (IL-6) is the major activator of the acute phase response (APR). One important regulator of IL-6-activated APR is peroxisome proliferator-activated receptor alpha (PPAR
Interleukin-6 Induces the down regulation of human peroxisome proliferator activated receptor alpha via the MAPK-induced STAT pathway in human hepatocytes
- Authors: Chew, Guatsiew , Myers, Stephen , Ooi, Kheng Leong , Alexander Chong, Shu-Chien , Sifzizul Tengku Muhammad, Tengku
- Date: 2013
- Type: Text , Journal article
- Relation: Journal of Biochemical and Pharmacological Research Vol. 1, no. 4 (December 2013 2013), p. 204-211
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- Description: IL-6 plays a crucial role in the development of acute phase response. One of the important regulators of IL-6-activated APR is peroxisome proliferator activated receptor alpha (PPAR
Renal Mechanisms of Association between Fibroblast Growth Factor 1 and Blood Pressure
- Authors: Tomaszewski, Maciej , Eales, James , Denniff, Matthew , Myers, Stephen , Chew, Guatsiew , Nelson, Christopher , Christofidou, Paraskevi , Desai, Aishwarya , Büsst, Cara , Wojnar, Lukasz , Musialik, Katarzyna , Jozwiak, Jacek , Debiec, Radoslaw , Dominiczak, Anna , Navis, Gerjan , van Gilst, Wiek , van der Harst, Pim , Samani, Nilesh , Harrap, Stephen , Bogdanski, Pawel , Zukowska-Szczechowska, Ewa , Charchar, Fadi
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of the American Society of Nephrology Vol. 26, no. 12 (2015), p. 3151-3160
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
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- Description: The fibroblast growth factor 1 (FGF1) gene is expressed primarily in the kidney and may contribute to hypertension. However, the biologic mechanisms underlying the association between FGF1 and BP regulation remain unknown. We report that the major allele of FGF1 single nucleotide polymorphism rs152524 was associated in a dose-dependent manner with systolic BP (P=9.65 x10(-5)) and diastolic BP (P=7.61 x10(-3)) in a meta-analysis of 14,364 individuals and with renal expression of FGF1 mRNA in 126 human kidneys (P=9.0x10(-3)). Next-generation RNA sequencing revealed that upregulated renal expression of FGF1 or of each of the three FGF1 mRNA isoforms individually was associated with higher BP. FGF1-stratified coexpression analysis in two separate collections of human kidneys identified 126 FGF1 partner mRNAs, of which 71 and 63 showed at least nominal association with systolic and diastolic BP, respectively. Of those mRNAs, seven mRNAs in five genes (MME, PTPRO, REN, SLC12A3, and WNK1) had strong prior annotation to BP or hypertension. MME, which encodes an enzyme that degrades circulating natriuretic peptides, showed the strongest differential coexpression with FGF1 between hypertensive and normotensive kidneys. Furthermore, higher level of renal FGF1 expression was associated with lower circulating levels of atrial and brain natriuretic peptides. These findings indicate that FGF1 expression in the kidney is at least under partial genetic control and that renal expression of several FGF1 partner genes involved in the natriuretic peptide catabolism pathway, reninangiotensin cascade, and sodium handling network may explain the association between FGF1 and BP.
Coronary artery disease : Why we should consider the Y chromosome
- Authors: Molina, Elsa , Clarence, Elyse , Ahmady, Farah , Chew, Guatsiew , Charchar, Fadi
- Date: 2016
- Type: Text , Journal article , Review
- Relation: Heart Lung and Circulation Vol. 25, no. 8 (Aug 2016), p. 791-801
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
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- Description: Coronary artery disease (CAD) is one of the leading causes of morbidity and mortality globally. In the last few years our understanding of the genetic and molecular mechanisms that promote CAD in individuals has increased with the advent of the genome era. This complex inflammatory disease has well-defined environmental risk factors. However, in the last 10 years, studies including genome-wide association studies (GWAS) have clearly demonstrated a genetic influence on CAD. Recently, studies on the human Y chromosome have also demonstrated that genetic variation within the male-specific region of the Y chromosome (MSY) could play a part in determining cardiovascular risk in men, confirming the notion that the increased risk for CAD in men cannot be fully explained through common CAD risk factors. Here, we review the literature about the pathophysiology of CAD, its potential causes and environmental risk factors known so far. Furthermore, we review the genetics of CAD, especially the latest discoveries regarding the implication of the Y chromosome, the most underexplored portion of the human genome to date, highlighting methods and difficulties arising in this research field, and discussing the importance of considering the Y chromosome in CAD research.