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GC-MS fingerprint of Pogostemon cablin in China

Hu LF, Li SP, Cao H, Liu JJ, Gao JL, Yang FQ, et al.

J Pharm Biomed Anal, 2006 Sep 18;42(2):200-6.
PMID: 16242880

Pogostemon cablin, originating in Malaysia and India, is cultivated in southern China including Guangdong and Hainan Province, which was called GuangHuoXiang to differentiate it from the HuoXiang of the north, the species Agastache rugosa, that it resembles. Essential oil of P. cablin mainly contributes to the pharmacological activities and the therapeutic properties of the essential oils are directly correlated with their qualitative and quantitative composition. For controlling the quality, standard fingerprint of P. cablin collected from different regions was developed by using GC-MS. Nine compounds including beta-patchoulene, caryophyllene, alpha-guaiene, seychellene, beta-guaiene, delta-guaiene, spathulenol, patchouli alcohol and pogostone were identified among 10 main peaks in P. cablin. Hierarchical clustering analysis based on characteristics of 10 investigated peaks in GC profiles showed that 18 samples were divided into three main clusters, patchouliol-type, pogostone-type and an interim-type, which was the one between the two chemotypes. The simulative mean chromatogram for the three types P. cablin was generated using the Computer Aided Similarity Evaluation System. The fingerprint can help to distinguish the substitute or adulterant, and further assess the differences of P. cablin grown in various areas of China.
Obesity is a determinant of arterial stiffness independent of traditional risk factors in Asians with young-onset type 2 diabetes

Liu JJ, Sum CF, Tavintharan S, Yeoh LY, Ng XW, Moh AM, et al.

Atherosclerosis, 2014 Oct;236(2):286-91.
PMID: 25112799 DOI: 10.1016/j.atherosclerosis.2014.07.017

OBJECTIVE: Type 2 diabetes (T2DM) among the young population has become a serious concern globally, presumably due to the rising trend of obesity. Compared to other forms of diabetes, young-onset T2DM experiences more cardiovascular events and other vascular complications although the underlying mechanisms remain largely unknown. Increased arterial stiffness is a hallmark of vasculopathy. We aim to study the clinical and metabolic determinants of arterial stiffness in a cohort of multi-ethnic Asians with young-onset T2DM.
METHODS: 179 subjects with T2DM onset age below 30 years old were selected in this cross sectional study. Arterial stiffness was assessed by carotid-femoral pulse wave velocity (PWV).
RESULTS: PWV was correlated with age, duration of diabetes, systolic blood pressure, alanine aminotransferase, urinary albumin-to-creatinine ratio (ACR) and eGFR in bivariate correlation analysis. However, PWV was only significantly correlated with body mass index (BMI), waist circumference, urinary ACR and eGFR after adjustment for age. Overweight individuals with young-onset T2DM had significantly higher PWV levels compared to their lean counterparts (7.3 ± 2.4 m/s vs 6.4 ± 2.3 m/s, p = 0.072 and p < 0.0001 without and with adjustment for age, respectively). Multivariable regression models revealed that age, BMI, eGFR and usage of insulin were independently associated with PWV. These 4 variables explained 35.5% variance in PWV levels.
CONCLUSION: Age, BMI, renal function and insulin usage are the main determinants of PWV levels in Asians with young-onset T2DM. Notably, obesity is a modifiable determinant of arterial stiffness independent of high blood pressure, dyslipidemia and hyperglycemia in this population.
Fulltext Clinical Determinants of Diabetes Progression in Multiethnic Asians with Type 2 Diabetes - A 3-Year Prospective Cohort Study

Liu S, Liu JJ, Gurung RL, Chan C, Yeo D, Ang K, et al.

Ann Acad Med Singap, 2019 Jul;48(7):217-223.
PMID: 31495867

INTRODUCTION: The risk for diabetes progression varies greatly in individuals with type 2 diabetes mellitus (T2DM). We aimed to study the clinical determinants of diabetes progression in multiethnic Asians with T2DM.

MATERIALS AND METHODS: A total of 2057 outpatients with T2DM from a secondary-level Singapore hospital were recruited for the study. Diabetes progression was defined as transition from non-insulin use to requiring sustained insulin treatment or glycated haemoglobin (HbA1c) ≥8.5% when treated with 2 or more oral hypoglycaemic medications. Multivariable logistic regression (LR) was used to study the clinical and biochemical variables that were independently associated with diabetes progression. Forward LR was then used to select variables for a parsimonious model.

RESULTS: A total of 940 participants with no insulin use or indication for insulin treatment were analysed. In 3.2 ± 0.4 (mean ± SD) years' follow-up, 163 (17%) participants experienced diabetes progression. Multivariable LR revealed that age at T2DM diagnosis (odds ratio [95% confidence interval], 0.96 [0.94-0.98]), Malay ethnicity (1.94 [1.19-3.19]), baseline HbA1c (2.22 [1.80-2.72]), body mass index (0.96 [0.92-1.00]) and number of oral glucose-lowering medications (1.87 [1.39-2.51]) were independently associated with diabetes progression. Area under receiver operating characteristic curve of the parsimonious model selected by forward LR (age at T2DM diagnosis, Malay ethnicity, HbA1c and number of glucose-lowering medication) was 0.76 (95% CI, 0.72-0.80).

CONCLUSION: Young age at T2DM diagnosis, high baseline HbA1c and Malay ethnicity are independent determinants of diabetes progression in Asians with T2DM. Further mechanistic studies are needed to elucidate the pathophysiology underpinning progressive loss of glycaemic control in patients with T2DM.
Ethnic disparity in central arterial stiffness and its determinants among Asians with type 2 diabetes

Zhang X, Liu JJ, Sum CF, Ying YL, Tavintharan S, Ng XW, et al.

Atherosclerosis, 2015 Sep;242(1):22-8.
PMID: 26162317 DOI: 10.1016/j.atherosclerosis.2015.06.019

OBJECTIVE: We previously reported ethnic disparity in adverse outcomes among Asians with type 2 diabetes (T2DM) in Singapore. Central arterial stiffness can aggravate systemic vasculopathy by propagating elevated systolic and pulse pressures forward, thereby accentuating global vascular injury. We aim to study ethnic disparity in central arterial stiffness and its determinants in a multi-ethnic T2DM Asian cohort.
METHODS: Arterial stiffness was estimated by carotid-femoral pulse wave velocity (PWV) and augmentation index (AI) using applanation tonometry method in Chinese (N = 1045), Malays (N = 458) and Indians (N = 468). Linear regression model was used to evaluate predictors of PWV and AI.
RESULTS: PWV was higher in Malays (10.1 ± 3.0 m/s) than Chinese (9.7 ± 2.8 m/s) and Indians (9.6 ± 3.1 m/s) (P = 0.018). AI was higher in Indians (28.1 ± 10.8%) than Malays (25.9 ± 10.1%) and Chinese (26.1 ± 10.7%) (P < 0.001). Malays remain associated with higher PWV (β = 0.299, P = 0.048) post-adjustment for age, gender, duration of diabetes, hemoglobin A1c, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), soluble receptor for advanced glycation end-products, urinary albumin-to-creatinine ratio, and insulin usage, which were all independent predictors of PWV. Indians remain associated with higher AI (β = 2.776, P < 0.001) post-adjustment for age, gender, BMI, SBP, DBP, and height, which were independent predictors of AI. These variables explained 27.7% and 33.4% of the variance in PWV and AI respectively.
CONCLUSIONS: Malays and Indians with T2DM have higher central arterial stiffness, which may explain their higher risk for adverse outcomes. Modifying traditional major vascular risk factors may partially alleviate their excess cardiovascular risk through modulating arterial stiffness.
KEYWORDS: Arterial stiffness; Augmentation index; Pulse wave velocity; Type 2 diabetes
[Exploring molecular mechanisms of fucoidan in improving human proximal renal tubular epithelial cells aging by targeting autophagy signaling pathways]

Fang QJ, Liu JJ, Wan YG, Liu BH, Tu Y, Wu W, et al.

Zhongguo Zhong Yao Za Zhi, 2020 Dec;45(24):6003-6011.
PMID: 33496141 DOI: 10.19540/j.cnki.cjcmm.20200709.401

Fucoidan(FPS) is an effective component of the Chinese patent medicine named Haikun Shenxi, which treats schronic renal failure in clinics, and has the potential anti-aging effects. However, it is still unclear whether FPS can improve renal aging, especially the molecular mechanism of its anti-aging. The human proximal renal tubular epithelial cells(HK-2) in vitro were divided into normal group(N), D-gal model group(D), low dose of FPS group(L-FPS), high dose of FPS group(H-FPS) and vitamin E group(VE), and treated by the different measures, respectively. More specifically, the HK-2 cells in each group were separately treated by 1 mL of 1% fetal bovine serum(FBS) or D-galactose(D-gal, 75 mmol·L~(-1)) or D-gal(75 mmol·L~(-1))+FPS(25 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+FPS(50 μg·mL~(-1)) or D-gal(75 mmol·L~(-1))+VE(50 μg·mL~(-1)). After the treatment for 24 h, firstly, the effects of D-gal on senescence-associated β-galactosidase(SA-β-gal) staining characteristics and klotho, P53 and P21 protein expression le-vels, as well as adenosine monophosphate activated protein kinase(AMPK)-uncoordinated 51-like kinase 1(ULK1) signaling pathway activation in the HK-2 cells were detected, respectively. Secondly, the effects of FPS and VE on SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal were investigated, respectively. Finally, the effects of FPS and VE on microtubule-associated protein 1 light chain 3(LC3) protein expression level and AMPK-ULK1 signaling pathway activation in the HK-2 cells exposed to D-gal were examined severally. The results indicated that, for the HK-2 cells, the dose of 75 mmol·L~(-1) D-gal could induce the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels. That is causing cells aging. FPS and VE could both ameliorate the changes of SA-β-gal staining characteristics and klotho, P53 and P21 protein expression levels in the HK-2 cells exposed to D-gal. That is anti-cells aging, here, the functions of FPS and VE are similar. D-gal could not only induce cell aging but also increase LC3Ⅱ, phosphorylated-AMPK(p-AMPK) and phosphorylated-ULK1(p-ULK1) protein expressions, and activate autophagy-related AMPK-ULK1 signaling pathway. FPS and VE could both improve the changes of LC3Ⅱ, p-AMPK and p-ULK1 protein expression levels in the HK-2 cells exposed to D-gal. That is inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. On the whole, for the human proximal renal tubular epithelial cells aging models induced by D-gal, FPS similar to VE, can ameliorate renal cells aging by possibly inhibiting autophagy-related AMPK-ULK1 signaling pathway activation. This finding provides the preliminary pharmacologic evidences for FPS protecting against renal aging.
Erratum to: recurrent mutation testing of BRCA1 and BRCA2 in Asian breast cancer patients identify carriers in those with presumed low risk by family history

Kang PC, Phuah SY, Sivanandan K, Kang IN, Thirthagiri E, Liu JJ, et al.

Breast Cancer Res Treat, 2015 Apr;150(3):699-700.
PMID: 25833212 DOI: 10.1007/s10549-015-3360-0
Recurrent mutation testing of BRCA1 and BRCA2 in Asian breast cancer patients identify carriers in those with presumed low risk by family history

Kang PC, Phuah SY, Sivanandan K, Kang IN, Thirthagiri E, Liu JJ, et al.

Breast Cancer Res Treat, 2014 Apr;144(3):635-42.
PMID: 24578176 DOI: 10.1007/s10549-014-2894-x

Although the breast cancer predisposition genes BRCA1 and BRCA2 were discovered more than 20 years ago, there remains a gap in the availability of genetic counselling and genetic testing in Asian countries because of cost, access and inaccurate reporting of family history of cancer. In order to improve access to testing, we developed a rapid test for recurrent mutations in our Asian populations. In this study, we designed a genotyping assay with 55 BRCA1 and 44 BRCA2 mutations previously identified in Asian studies, and validated this assay in 267 individuals who had previously been tested by full sequencing. We tested the prevalence of these mutations in additional breast cancer cases. Using this genotyping approach, we analysed recurrent mutations in 533 Malaysian breast cancer cases with <10 % a priori risk, and found 1 BRCA1 (0.2 %) and 5 BRCA2 (0.9 %) carriers. Testing in a hospital-based unselected cohort of 532 Singaporean breast cancer cases revealed 6 BRCA1 (1.1 %) and 3 BRCA2 (0.6 %) carriers. Overall, 2 recurrent BRCA1 and 1 BRCA2 mutations in Malays, 3 BRCA1 and 2 BRCA2 mutations in Chinese and 1 BRCA1 mutation in Indians account for 60, 24 and 20 % of carrier families, respectively. By contrast, haplotype analyses suggest that a recurrent BRCA2 mutation (c.262_263delCT) found in 5 unrelated Malay families has at least 3 distinct haplotypes. Taken together, our data suggests that panel testing may help to identify carriers, particularly Asian BRCA2 carriers, who do not present with a priori strong family history characteristics.
Fulltext X-chromosome association study reveals genetic susceptibility loci of nasopharyngeal carcinoma

Zuo XY, Feng QS, Sun J, Wei PP, Chin YM, Guo YM, et al.

Biol Sex Differ, 2019 03 25;10(1):13.
PMID: 30909962 DOI: 10.1186/s13293-019-0227-9

BACKGROUND: The male predominance in the incidence of nasopharyngeal carcinoma (NPC) suggests the contribution of the X chromosome to the susceptibility of NPC. However, no X-linked susceptibility loci have been examined by genome-wide association studies (GWASs) for NPC by far.
METHODS: To understand the contribution of the X chromosome in NPC susceptibility, we conducted an X chromosome-wide association analysis on 1615 NPC patients and 1025 healthy controls of Guangdong Chinese, followed by two validation analyses in Taiwan Chinese (n = 562) and Malaysian Chinese (n = 716).
RESULTS: Firstly, the proportion of variance of X-linked loci over phenotypic variance was estimated in the discovery samples, which revealed that the phenotypic variance explained by X chromosome polymorphisms was estimated to be 12.63% (non-dosage compensation model) in males, as compared with 0.0001% in females. This suggested that the contribution of X chromosome to the genetic variance of NPC should not be neglected. Secondly, association analysis revealed that rs5927056 in DMD gene achieved X chromosome-wide association significance in the discovery sample (OR = 0.81, 95% CI 0.73-0.89, P = 1.49 × 10-5). Combined analysis revealed rs5927056 for DMD gene with suggestive significance (P = 9.44 × 10-5). Moreover, the female-specific association of rs5933886 in ARHGAP6 gene (OR = 0.62, 95%CI: 0.47-0.81, P = 4.37 × 10-4) was successfully replicated in Taiwan Chinese (P = 1.64 × 10-2). rs5933886 also showed nominally significant gender × SNP interaction in both Guangdong (P = 6.25 × 10-4) and Taiwan datasets (P = 2.99 × 10-2).
CONCLUSION: Our finding reveals new susceptibility loci at the X chromosome conferring risk of NPC and supports the value of including the X chromosome in large-scale association studies.
Fulltext A GWAS Meta-analysis and Replication Study Identifies a Novel Locus within CLPTM1L/TERT Associated with Nasopharyngeal Carcinoma in Individuals of Chinese Ancestry

Bei JX, Su WH, Ng CC, Yu K, Chin YM, Lou PJ, et al.

Cancer Epidemiol Biomarkers Prev, 2016 Jan;25(1):188-192.
PMID: 26545403 DOI: 10.1158/1055-9965.EPI-15-0144

BACKGROUND: Genetic loci within the major histocompatibility complex (MHC) have been associated with nasopharyngeal carcinoma (NPC), an Epstein-Barr virus (EBV)-associated cancer, in several GWAS. Results outside this region have varied.
METHODS: We conducted a meta-analysis of four NPC GWAS among Chinese individuals (2,152 cases; 3,740 controls). Forty-three noteworthy findings outside the MHC region were identified and targeted for replication in a pooled analysis of four independent case-control studies across three regions in Asia (4,716 cases; 5,379 controls). A meta-analysis that combined results from the initial GWA and replication studies was performed.
RESULTS: In the combined meta-analysis, rs31489, located within the CLPTM1L/TERT region on chromosome 5p15.33, was strongly associated with NPC (OR = 0.81; P value 6.3 × 10(-13)). Our results also provide support for associations reported from published NPC GWAS-rs6774494 (P = 1.5 × 10(-12); located in the MECOM gene region), rs9510787 (P = 5.0 × 10(-10); located in the TNFRSF19 gene region), and rs1412829/rs4977756/rs1063192 (P = 2.8 × 10(-8), P = 7.0 × 10(-7), and P = 8.4 × 10(-7), respectively; located in the CDKN2A/B gene region).
CONCLUSIONS: We have identified a novel association between genetic variation in the CLPTM1L/TERT region and NPC. Supporting our finding, rs31489 and other SNPs in this region have been reported to be associated with multiple cancer sites, candidate-based studies have reported associations between polymorphisms in this region and NPC, the TERT gene has been shown to be important for telomere maintenance and has been reported to be overexpressed in NPC, and an EBV protein expressed in NPC (LMP1) has been reported to modulate TERT expression/telomerase activity.
IMPACT: Our finding suggests that factors involved in telomere length maintenance are involved in NPC pathogenesis.
Fulltext Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.

Autophagy, 2016;12(1):1-222.
PMID: 26799652 DOI: 10.1080/15548627.2015.1100356

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