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Fulltext Immunomodulatory properties of Tamm-Horsfall glycoprotein (THP) and uromodulin

Hong CY, Wong NK, Abdullah M

Asian Pac J Allergy Immunol, 2015 Mar;33(1):26-32.
PMID: 25840631 DOI: 10.12932/AP0463.33.1.2015

Tamm-Horsfall glycoprotein (THP) and uromodulin are the most abundant glycoproteins in non-pregnant women's/men's and pregnant women's urine, respectively. However, the bioactivities of these glycoproteins are still unclear.

Matched MeSH terms: Primary Cell Culture
Fulltext Socio-economic development and mortality patterns and trends in Malaysia

Tan Poo Chang, Kwok Kwan Kit, Tan Boon Ann, Shyamala Nagaraj, Tey Nai Peng, Siti Norazah Zulkifli

Asia Pac Popul J, 1987 Mar;2(1):3-20.
PMID: 12341034

PIP: Morality in Peninsular Malaysia has reached a level that is quite similar to that prevailing in the low mortality countries. This article systematically documents changes in mortality levels and differentials in Malaysia over time and relates these to changes in development indicators and health-related policies. Remedial measures undertaken by the authorities including the expansion of hospital and health services into the estates, together with a comprehensive malaria-eradication program, improvements in sanitation laws, and increased provision of public utilities and education, resulted in beriberi being eliminated and the incidence of malaria, typhus, and smallpox being greatly reduced by the time of World War II. The gain in life expectancy over the period of 1957-1979 was greatest for the Malay, the most significant period being 1957-1967, which saw the introduction of rural health programs. The infant mortality rate and the neonatal and post-neonatal rates declined substantially for all ethnic groups in Peninsular Malaysia for the same time period. Although the lower infant mortality of the Chinese can be explained by their advantageous socioeconomic position the same reason cannot explain the lower decline in infant mortality levels of the Indians. Much still needs to be done to narrow, if not to eliminate, the existing mortality differentials of different groups in the country. Overall, the quality of life of the general population can be further enhanced by reducing the high mortality level of disadvantaged groups.

Matched MeSH terms: Culture
Paeonol protects against endoplasmic reticulum stress-induced endothelial dysfunction via AMPK/PPARδ signaling pathway

Choy KW, Mustafa MR, Lau YS, Liu J, Murugan D, Lau CW, et al.

Biochem Pharmacol, 2016 09 15;116:51-62.
PMID: 27449753 DOI: 10.1016/j.bcp.2016.07.013

Endoplasmic reticulum (ER) stress in endothelial cells often leads to endothelial dysfunction which underlies the pathogenesis of cardiovascular diseases. Paeonol, a major phenolic component extracted from Moutan Cortex, possesses various medicinal benefits which have been used extensively in traditional Chinese medicine. The present study investigated the protective mechanism of paeonol against tunicamycin-induced ER stress in isolated mouse aortas and human umbilical vein endothelial cells (HUVECs). Vascular reactivity in aorta was measured using a wire myograph. The effects of paeonol on protein expression of ER stress markers, reactive oxygen species (ROS) production, nitric oxide (NO) bioavailability and peroxisome proliferator-activated receptor δ (PPARδ) activity in the vascular wall were assessed by Western blot, dihydroethidium fluorescence (DHE) or lucigenin enhanced-chemiluminescence, 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM DA) and dual luciferase reporter assay, respectively. Ex vivo treatment with paeonol (0.1μM) for 16h reversed the impaired endothelium-dependent relaxations in C57BJ/6J and PPARδ wild type (WT) mouse aortas following incubation with tunicamycin (0.5μg/mL). Elevated ER stress markers, oxidative stress and reduction of NO bioavailability induced by tunicamycin in HUVECs, C57BJ/6J and PPARδ WT mouse aortas were reversed by paeonol treatment. These beneficial effects of paeonol were diminished in PPARδ knockout (KO) mouse aortas. Paeonol increased the expression of 5' adenosine monophosphate-activated protein kinase (AMPK) and PPARδ expression and activity while restoring the decreased phosphorylation of eNOS. The present study delineates that paeonol protects against tunicamycin-induced vascular endothelial dysfunction by inhibition of ER stress and oxidative stress, thus elevating NO bioavailability via the AMPK/PPARδ signaling pathway.

Matched MeSH terms: Tissue Culture Techniques
Fulltext Differential Response of Gestational Tissues to TLR3 Viral Priming Prior to Exposure to Bacterial TLR2 and TLR2/6 Agonists

Rasheed ZBM, Lee YS, Kim SH, Rai RK, Ruano CSM, Anucha E, et al.

Front Immunol, 2020;11:1899.
PMID: 32983111 DOI: 10.3389/fimmu.2020.01899

Background: Infection/inflammation is an important causal factor in spontaneous preterm birth (sPTB). Most mechanistic studies have concentrated on the role of bacteria, with limited focus on the role of viruses in sPTB. Murine studies support a potential multi-pathogen aetiology in which a double or sequential hit of both viral and bacterial pathogens leads to a higher risk preterm labour. This study aimed to determine the effect of viral priming on bacterial induced inflammation in human in vitro models of ascending and haematogenous infection. Methods: Vaginal epithelial cells, and primary amnion epithelial cells and myocytes were used to represent cell targets of ascending infection while interactions between peripheral blood mononuclear cells (PBMCs) and placental explants were used to model systemic infection. To model the effect of viral priming upon the subsequent response to bacterial stimuli, each cell type was stimulated first with a TLR3 viral agonist, and then with either a TLR2 or TLR2/6 agonist, and responses compared to those of each agonist alone. Immunoblotting was used to detect cellular NF-κB, AP-1, and IRF-3 activation. Cellular TLR3, TLR2, and TLR6 mRNA was quantified by RT-qPCR. Immunoassays were used to measure supernatant cytokine, chemokine and PGE2 concentrations. Results: TLR3 ("viral") priming prior to TLR2/6 agonist ("bacterial") exposure augmented the pro-inflammatory, pro-labour response in VECs, AECs, myocytes and PBMCs when compared to the effects of agonists alone. In contrast, enhanced anti-inflammatory cytokine production (IL-10) was observed in placental explants. Culturing placental explants in conditioned media derived from PBMCs primed with a TLR3 agonist enhanced TLR2/6 agonist stimulated production of IL-6 and IL-8, suggesting a differential response by the placenta to systemic inflammation compared to direct infection as a result of haematogenous spread. TLR3 agonism generally caused increased mRNA expression of TLR3 and TLR2 but not TLR6. Conclusion: This study provides human in vitro evidence that viral infection may increase the susceptibility of women to bacterial-induced sPTB. Improved understanding of interactions between viral and bacterial components of the maternal microbiome and host immune response may offer new therapeutic options, such as antivirals for the prevention of PTB.

Matched MeSH terms: Tissue Culture Techniques
Fulltext Targeting MHC Regulation Using Polycyclic Polyprenylated Acylphloroglucinols Isolated from Garcinia bancana

Coste C, Gérard N, Dinh CP, Bruguière A, Rouger C, Leong ST, et al.

Biomolecules, 2020 09 02;10(9).
PMID: 32887413 DOI: 10.3390/biom10091266

Modulation of major histocompatibility complex (MHC) expression using drugs has been proposed to control immunity. Phytochemical investigations on Garcinia species have allowed the isolation of bioactive compounds such as polycyclic polyprenylated acylphloroglucinols (PPAPs). PPAPs such as guttiferone J (1), display anti-inflammatory and immunoregulatory activities while garcinol (4) is a histone acetyltransferases (HAT) p300 inhibitor. This study reports on the isolation, identification and biological characterization of two other PPAPs, i.e., xanthochymol (2) and guttiferone F (3) from Garcinia bancana, sharing structural analogy with guttiferone J (1) and garcinol (4). We show that PPAPs 1-4 efficiently downregulated the expression of several MHC molecules (HLA-class I, -class II, MICA/B and HLA-E) at the surface of human primary endothelial cells upon inflammation. Mechanistically, PPAPs 1-4 reduce MHC proteins by decreasing the expression and phosphorylation of the transcription factor STAT1 involved in MHC upregulation mediated by IFN-γ. Loss of STAT1 activity results from inhibition of HAT CBP/p300 activity reflected by a hypoacetylation state. The binding interactions to p300 were confirmed through molecular docking. Loss of STAT1 impairs the expression of CIITA and GATA2 but also TAP1 and Tapasin required for peptide loading and transport of MHC. Overall, we identified new PPAPs issued from Garcinia bancana with potential immunoregulatory properties.

Matched MeSH terms: Primary Cell Culture
Fulltext Nutritional anemia in pregnancy: a study at the maternity hospital, Kuala Lumpur

Tee ES, Kandiah M, Ali J, Kandiah V, Zahari MR, Kuladevan R, et al.

Malays J Reprod Health, 1984 Jun;2(1):32-50.
PMID: 12267519

The study presents recent data on the prevalence and pattern of nutritional anemia in the Maternity Hospital, Kuala Lumpur. A total of 309 pregnant women in their third trimester, of Malay, Chinese and Indian origin from the lower socio-economic strata were randomly selected for the study. Hematological indices (including Hb, PCV, MCHC, and TRBC), serum iron, transferrin saturation and ferritin, serum folate as well as protein and albumin were determined. Based on Hb and PCV values, 30-40 percent of the women could be considered anemic; approximately 50 percent of them presented with unsatisfactory serum iron, transferrin saturation and ferritin values; 60.9 percent had low serum folate levels; and about 30 percent may be considered to be of poor protein nutriture. Anemia in the study population was seen to be related mostly to iron and to a lesser extent, folate deficiency. Hematological, iron, folate and protein status was observed to be the poorest amongst the Indian women, better in the Malay group and generally the best amongst the Chinese women. Birth records of 169 of these women revealed that all of them had live births. Nearly all the infants were delivered by normal vaginal delivery (NVD) The mean gestational age was 38.6 weeks. One of the infants had a birth weight of <2.0 kg; incidence of low birth weight, <2.5 kg, was 8.3 percent. Although there was a trend of deteriorating hematological, iron and protein status of women from the 0, 1 -3 and >=4 parity groups, these differences were not statlstlcally significant.

Matched MeSH terms: Culture
Multivariate areal analysis of the impact and efficiency of the family planning programme in peninsular Malaysia

Tan Boon Ann

Asia Pac Popul J, 1987 Jun;2(2):45-66.
PMID: 12341280
Matched MeSH terms: Culture
Oleoyl-lysophosphatidylinositol enhances glucagon-like peptide-1 secretion from enteroendocrine L-cells through GPR119

Arifin SA, Paternoster S, Carlessi R, Casari I, Ekberg JH, Maffucci T, et al.

Biochim Biophys Acta Mol Cell Biol Lipids, 2018 09;1863(9):1132-1141.
PMID: 29883799 DOI: 10.1016/j.bbalip.2018.06.007

The gastrointestinal tract is increasingly viewed as critical in controlling glucose metabolism, because of its role in secreting multiple glucoregulatory hormones, such as glucagon like peptide-1 (GLP-1). Here we investigate the molecular pathways behind the GLP-1- and insulin-secreting capabilities of a novel GPR119 agonist, Oleoyl-lysophosphatidylinositol (Oleoyl-LPI). Oleoyl-LPI is the only LPI species able to potently stimulate the release of GLP-1 in vitro, from murine and human L-cells, and ex-vivo from murine colonic primary cell preparations. Here we show that Oleoyl-LPI mediates GLP-1 secretion through GPR119 as this activity is ablated in cells lacking GPR119 and in colonic primary cell preparation from GPR119-/- mice. Similarly, Oleoyl-LPI-mediated insulin secretion is impaired in islets isolated from GPR119-/- mice. On the other hand, GLP-1 secretion is not impaired in cells lacking GPR55 in vitro or in colonic primary cell preparation from GPR55-/- mice. We therefore conclude that GPR119 is the Oleoyl-LPI receptor, upstream of ERK1/2 and cAMP/PKA/CREB pathways, where primarily ERK1/2 is required for GLP-1 secretion, while CREB activation appears dispensable.

Matched MeSH terms: Primary Cell Culture
Effects of ranibizumab on TGF-β1 and TGF-β2 production by human Tenon's fibroblasts: An in vitro study

Noh SM, Abdul Kadir SH, Crowston JG, Subrayan V, Vasudevan S

Mol Vis, 2015;21:1191-200.
PMID: 26539031

Inhibiting exaggerated wound healing responses, which are primarily mediated by human Tenon's fibroblast (HTF) migration and proliferation, has become the major determining factor for a successful trabeculectomy. Antivascular endothelial growth factor (anti-VEGF) has showed promising results as a potential antifibrotic candidate for use concurrently in trabeculectomy. Preliminary cohort studies have revealed improved bleb morphology following trabeculectomy augmented with ranibizumab. However, the effects on HTFs remain unclear. This study was conducted to understand the effects of ranibizumab on transforming growth factor (TGF)-β1 and transforming growth factor (TGF)-β2 expression by HTFs.

Matched MeSH terms: Primary Cell Culture
Fulltext Inhibition of Egr1 expression underlies the anti-mitogenic effects of cAMP in vascular smooth muscle cells

Kimura TE, Duggirala A, Hindmarch CC, Hewer RC, Cui MZ, Newby AC, et al.

J Mol Cell Cardiol, 2014 Jul;72(100):9-19.
PMID: 24534707 DOI: 10.1016/j.yjmcc.2014.02.001

AIMS: Cyclic AMP inhibits vascular smooth muscle cell (VSMC) proliferation which is important in the aetiology of numerous vascular diseases. The anti-mitogenic properties of cAMP in VSMC are dependent on activation of protein kinase A (PKA) and exchange protein activated by cAMP (EPAC), but the mechanisms are unclear.
METHODS AND RESULTS: Selective agonists of PKA and EPAC synergistically inhibited Egr1 expression, which was essential for VSMC proliferation. Forskolin, adenosine, A2B receptor agonist BAY60-6583 and Cicaprost also inhibited Egr1 expression in VSMC but not in endothelial cells. Inhibition of Egr1 by cAMP was independent of cAMP response element binding protein (CREB) activity but dependent on inhibition of serum response element (SRE) activity. SRF binding to the Egr1 promoter was not modulated by cAMP stimulation. However, Egr1 expression was dependent on the SRF co-factors Elk1 and 4 but independent of MAL. Inhibition of SRE-dependent Egr1 expression was due to synergistic inhibition of Rac1 activity by PKA and EPAC, resulting in rapid cytoskeleton remodelling and nuclear export of ERK1/2. This was associated with de-phosphorylation of the SRF co-factor Elk1.
CONCLUSION: cAMP inhibits VSMC proliferation by rapidly inhibiting Egr1 expression. This occurs, at least in part, via inhibition of Rac1 activity leading to rapid actin-cytoskeleton remodelling, nuclear export of ERK1/2, impaired Elk1-phosphorylation and inhibition of SRE activity. This identifies one of the earliest mechanisms underlying the anti-mitogenic effects of cAMP in VSMC but not in endothelial cells, making it an attractive target for selective inhibition of VSMC proliferation.

Matched MeSH terms: Primary Cell Culture