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Objective To investigate the impact of the endogamous marriage culture on the prevalence of the hemoglobin E (HbE) recessive variant. Methods The prevalence of the hemoglobin E (HbE) recessive variant was determined by dot-blot hybridization in 4 endogamous villages (1 Mlabri and 3 Htin ethnic groups) in comparison with 9 other nearby non-endogamous populations. Results Although the overall HbE prevalence in the population studied (8.44%, 33/391) was not significantly different from that of the general southeast Asian population, a high prevalence and individuals with homozygous HbE were observed in two villages, the Mlabri from Wiang Sa district and the Htin from Thung Chang district of Nan province (26.3% and 26.9%, respectively). The low HbE allelic frequency noticed in some endogamous populations suggests that not only endogamy but also other evolutionary forces, such as founder effect and HbE/β-thalassemia negative selection may have an effect on the distribution of the HbE trait. Conclusion Our study strongly documents that cultural impact has to be considered in the extensive prevalence studies for genetic disorders in the ethnic groups of northern Thailand. [ABSTRACT FROM AUTHOR]

Iron deficiency anemia and iron overload conditions affect more than one billion people worldwide. Iron homeostasis involves the regulation of cells that export iron into the plasma and cells that utilize or store iron. The cellular iron balance in humans is primarily mediated by the hepcidin–ferroportin axis. Ferroportin is the sole cellular iron export protein, and its expression is regulated transcriptionally, post-transcriptionally and post-translationally. Hepcidin, a hormone produced by liver cells, post-translationally regulates ferroportin expression on iron exporting cells by binding with ferroportin and promoting its internalization by endocytosis and subsequent degradation by lysosomes. Dysregulation of iron homeostasis leading to iron deposition in vital organs is the main cause of death in beta-thalassemia patients. Beta-thalassemia patients show marked hepcidin suppression, ineffective erythropoiesis, anemia and iron overload. Beta-thalassemia is common in the Mediterranean region, Southeast Asia and the Indian subcontinent, and the focus of this review is to provide an update on the factors mediating hepcidin related iron dysregulation in beta-thalassemia disease. Understanding this process may pave the way for new treatments to ameliorate iron overloading and improve the long term prognosis of these patients. [ABSTRACT FROM AUTHOR]

Background: Elsholtzia is a genus in the family Lamiaceae, and some species in this genus are commonly used for food and in ethnomedicinal formulations by some ethnic groups of China and Thailand. Despite their apparent utility, few studies have been conducted to evaluate their potential as sources of medicinally active agents., Purpose: We aimed to investigate the cytotoxicity of ethanolic extracts from three selected edible plant species of the genus Elsholtzia and the most promising extract was further characterized for the bioactive constituents and signaling mechanisms associated with the anti-leukemic activity., Materials and Methods: Ethanolic extracts were screened for cytotoxicity using flow cytometry. HPLC and LC-MS were used to analyze the chemical constituents of the most potent fraction from E. stachyodes. The relevant mechanism of action was assessed by western blot and multispectral imaging flow cytometry (MIFC)., Results: The most potent anti-leukemic activity was observed with the ethanolic extract from E. stachyodes. Luteolin and apigenin were characterized as the major constituents in the fraction from E. stachyodes. Mechanistically, the luteolin-apigenin enriched fraction (LAEF) induced the UPR, increased autophagic flux, induced cell cycle arrest and apoptotic cell death. LAEF showed significantly less cytotoxicity towards peripheral blood mononuclear cells (PBMCs) as compared to leukemia cell lines., Conclusion: This study is the first to report E. stachyodes as a new source of luteolin and apigenin which are capable of triggering leukemic cell death. This could lead to a novel strategy against leukemia using ethnomedicinal plant extracts as an alternative or supplemental anti-cancer agent., Competing Interests: Conflict of Interest Statement The authors declare that they have no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

CD147/Basigin/EMMPRIN is overexpressed in several cancerous tissues and it has been shown to induce matrix metalloproteinases (MMPs) whose expression is associated with cancer metastasis. Thus, targeting CD147 with monoclonal antibodies (mAbs) potentially has therapeutic applications in cancer immunotherapy. Here, we report the use of anti-CD147 mAbs targeting domain 1 of CD147, namely M6-1D4 (IgM), M6-1F3 (IgM), M6-2F9 (IgM) and M6-1E9 (IgG2a), against several human cancer cell lines. Strikingly, IgM but not IgG mAbs against CD147, especially clone M6-1D4, induced acute cellular swelling, and this phenomenon appeared to be specifically found with hepatocellular carcinoma (HCC) cells. Furthermore, molecular investigation upon treating HepG2 cells with M6-1D4 showed unfolded protein response (UPR) activation, autophagosome accumulation, and cell cycle arrest, but without classic apoptosis related features. More interestingly, prolonged M6-1D4 treatment (24 h) resulted in irreversible oncosis leading to necroptosis. Furthermore, treatment with a mixed lineage kinase domain-like psuedokinase (MLKL) inhibitor and partial knockout of MLKL resulted in reduced sensitivity to necroptosis in M6-1D4-treated HepG2 cells. Surprisingly however, the observed necroptotic signaling axis appeared to be non-canonical as it was independent of receptor-interacting serine/threonine-protein kinase (RIPK) phosphorylation. In addition, no cytotoxic effect on human dermal fibroblast (HDF) was observed after incubation with M6-1D4. Taken together, this study provides clues to target CD147 in HCC using mAbs, as well as sheds new light on a novel strategy to kill cancerous cells by the induction of necroptosis., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Dimocarpus longan, commonly known as the longan, belongs to the family Sapindaceae, and is one of the most economically important fruits commonly cultivated in several regions in Asia. There are various cultivars of longan throughout the Thai-Malay peninsula region, but until now no phylogenetic analysis has been undertaken to determine the genetic relatedness of these cultivars. To address this issue, 6 loci, namely ITS2, matK, rbcL, trnH-psbA, trnL-I and trnL-trnF were amplified and sequenced from 40 individuals consisting of 26 longan cultivars 2 types of lychee and 8 herbarium samples. The sequencing results were used to construct a phylogenetic tree using the neighbor-joining (NJ), maximum likelihood (ML) and Bayesian inference (BI) criteria. The tree showed cryptic groups of D. longan from the Thailand-Malaysia region (Dimocarpus longan spp.). This is the first report of the genetic relationship of Dimocarpus based on multi-locus molecular markers and morphological characteristics. Multiple sequence alignments, phylogenetic trees and species delimitation support that Dimocarpus longan spp. longan var. obtusus and Dimocarpus longan spp. malesianus var. malesianus should be placed into a higher order and are two additional species in the genus Dimocarpus. Therefore these two species require nomenclatural changes as Dimocarpus malesianus and Dimocarpus obtusus, respectively.

Alpha (α)-thalassaemia is one of the most prevalent hereditary blood disorders, commonly affecting Southeast Asian people, with the highest incidence (30-40%) being seen in northern Thailand. However, this high incidence was estimated without consideration of the variations between ethnic populations and the geographical location of the populations. To address this issue, a total of 688 samples from 13 different northern Thai ethnic groups (30 villages) categorized into three linguistic groups were genotyped for deletional alpha-thalassaemia (-α 3.7 , -α 4.2 , -- SEA and -- THAI ) and/or non-deletional alpha-thalassaemia (α CS and α PS ) via multiplex gap-PCR and dot-blot hybridization, respectively. Alpha + (-α 3.7 , -α 4.2 , α CS and α PS ) and alpha°-thalassaemia (-- SEA and -- THAI ) allele frequencies (with 95% Confidence Interval) were the highest in the Sino-Tibetan group [0.13 (0.08-0.18)] and the Tai-Kadai group [0.03 (0.02-0.05)], respectively. With regards to ethnicity, the varying allele frequency of α + and α°-thalassaemia amongst a variety of ethnic groups was observed. The highest α + -thalassaemia allele frequency was found in the Paluang [0.21 (0.10-0.37)] while α°-thalassaemia allele frequency was the highest in the Yuan [0.04 (0.01-0.10)]. These detailed results of alpha thalassaemia allele frequency and genetic diversity amongst the northern Thai ethnic groups demonstrate the need for ethnicity based thalassaemia prevention programs.

Background: Uvaria longipes (Craib) L.L.Zhou, Y.C.F.Su & R.M.K.Saunders, Artabotrys burmanicus A.DC, Marsypopetalum modestum (Pierre) B.Xue & R.M.K.Saunders and Dasymaschalon sp. have been used for traditional medicine to treat cancer-like symptoms in some ethnic groups of Thailand and Laos., Methods: We evaluated the anti-cancer activity of these Annonaceae plants against several human cancer cell lines. The apoptosis induction was detected by Annexin/propidium iodide (PI) staining. Phytochemical screening was tested by standard protocols and bioactive compounds were determined by HPLC., Results: The crude extracts from leaves of U. longipes, Dasymaschalon sp., A. burmanicus, and M. modestum showed particular effects that were found to vary depending on the cancer cell line, suggesting that the effect was in a cell-type specific manner. Interestingly, the induction of apoptotic cell death was prominent by the leaves-derived crude extract of M. modestum. This crude was, therefore, subjected to cell cycle analysis by PI staining. Results showed that this crude extract arrested cell cycle and increased the percentage of cells in the SubG1 phase in some cancer cell lines. The phytochemical screening tests indicated that all crude extracts contained tannins and flavonoids. HPLC of flavonoids using standards identified rutin as an active compound in U. longipes and Dasymaschalon sp., whereas quercetin was found in U. longipes and M. modestum., Conclusions: These crude extracts provide a new source for rutin and quercetin, which might be capable of inducing cancer cell apoptotic death in a cell-type specific manner. This suggests, by analyzing the major bioactive compounds, the potential use of these crudes for chemotherapy in the future.

Ribosome biogenesis is the process of synthesis of the cellular ribosomes which mediate protein translation. Integral with the ribosomes are four cytoplasmic ribosomal RNAs (rRNAs) which show extensive post-transcriptional modifications including 2'-O-methylation and pseudouridylation. Several hereditary hematologic diseases including Diamond-Blackfan anemia have been shown to be associated with defects in ribosome biogenesis. Thalassemia is the most important hematologic inherited genetic disease worldwide, and this study examined the post-transcriptional ribose methylation status of three specific active sites of the 28S rRNA molecule at positions 1858, 4197 and 4506 of β-thalassemia trait carriers and normal controls. Samples from whole blood and cultured erythroid cells were examined. Results showed that site 4506 was hypermethylated in β-thalassemia trait carriers in both cohorts. Expression of fibrillarin, the ribosomal RNA methyltransferase as well as snoRNAs were additionally quantified by RT-qPCR and evidence of dysregulation was seen. Hemoglobin E trait carriers also showed evidence of dysregulation. These results provide the first evidence that ribosome biogenesis is dysregulated in β-thalassemia trait carriers., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A number of studies have used global protein profiling technologies on a range of patient samples to detect proteins that are differentially expressed in β-thalassemia/Hb E as an aid for understanding the physiopathology of this disease. Seven studies have identified a total of 111 unique, differentially expressed proteins. Seven proteins (prothrombin, alpha-1-antichymotrypsin, fibrinogen beta chain, hemoglobin beta, selenium-binding protein, microtubule-actin cross-linking factor and adenomatous polyposis coli protein 2) have been identified in two independent studies, whereas two proteins (carbonic anhydrase 1 and peroxiredoxin-2) have been identified in three independent studies. Both of these latter two proteins were consistently upregulated in the studies that identified them. Ontological analysis of all differentially regulated proteins identified "response to inorganic substances" as the most significant functional annotation cluster, which is consistent with iron overload being a major pathological consequence of this disease. Despite the range of samples investigated and the relatively small number of studies undertaken, a coherent picture of the mediators of the pathological consequences of β-thalassemia/Hb E disease is starting to emerge., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: Northern Thailand is one of the highest α-thalassemia incidence areas where 30-40% of inhabitants have been reported to carry aberrant α-globin genes. However, all previous α-thalassemia prevalence surveys in northern Thailand have been undertaken without consideration of ethnicity. Here we report the prevalence of α-thalassemia genes in 4 Tai (Yong, Yuan, Khuen, Lue) and 4 Mon-Khmer speaking populations (Blang, Mon, Paluang, Lawa)., Methods: DNA extracted from 141 individuals was genotyped for 4 α-thalassemia deletional types (--(SEA), --(THAI), -α(3.7), -α(4.2)) using MultiplexGap-PCR analysis and 2 non-deletional types (Hb CS, Hb Pakse) using dot-blot hybridization technique., Results and Discussion: A total of 33 α-thalassemia carrying individuals (23.4%) were detected of which 32 were heterozygotes and one was a homozygote. The most common α-thalassemia detected were -α(3.7) (17.7%) and --(SEA) (3.5%), while Hb CS was detected in 2.1% of cases. No occurrence of --(THAI), -α(4.2) and Hb Pakse was observed. The prevalence of α-thalassemia carriers varied between the different ethnic groups, with the Yuan having the highest prevalence of α-thalassemia carriers (50%) while the Lawa had the lowest prevalence (0%). The Paluang had a high prevalence (42%) of a single deletion type (-α(3.7)) possibly related to the endogamous marriage traditions of this ethnic group., Conclusion: The extreme variation of α-thalassemia prevalence among the different ethnic groups highlights the significantly different genetic backgrounds found in these peoples, as consequences of dissimilar cultures. Our study suggests that ethnicity must be considered in any of the disease-causing allele prevalence surveys in this region.

The compound β°-thalassemia/Hb E hemoglobinopathy is characterized by an unusually large range of presentation from essentially asymptomatic to a severe transfusion dependent state. While a number of factors are known that moderate presentation, these factors do not account for the full spectrum of presentation. Mitochondria are subcellular organelles that are pivotal in a number of cellular processes including oxidative phosphorylation and apoptosis. A mitochondrial protein enriched proteome was determined and validated from erythroblasts from normal controls and β°-thalassemia/Hb E patients of different severities. Mitochondria were evaluated through the use of mitotracker staining, analysis of relative mitochondrial genome number and evaluation of mitochondrial gene expression in addition to assay of overall cellular redox status through the use of alamarBlue assays. Fifty differentially regulated mitochondrial proteins were identified. Mitotracker staining revealed significant differences in staining between normal control erythroblasts and those from β°-thalassemia/Hb E patients. Differences in relative mitochondria number and gene expression were seen primarily in day 10 cells. Significant differences were seen in redox status as evaluated by alamarBlue staining in newly isolated CD34+ cells. Mitochondria mediate oxidative phosphorylation and apoptosis, both of which are known to be dysregulated in differentiating erythrocytes from β°-thalassemia/Hb E patients. The evidence presented here suggest that there are inherent differences in these cells as early as the erythroid progenitor cell stage, and that maximum deficit is seen coincident with high levels of globin gene expression.

Hemoglobin E (HbE) is one of the most common hemoglobin variants caused by a mutation in the β-globin gene, and found at high frequencies in various Southeast Asian groups. We surveyed HbE prevalence among 8 ethnic groups residing in 5 villages selected for their high period malaria endemicity, and 5 for low endemicity in northern Thailand, in order to uncover factors which may affect genetic persistence of HbE in these groups. We found the overall HbE prevalence 6.7%, with differing frequencies from 0% in the Pwo Karen, the Lawa, and the Skaw Karen to 24% in the Mon. All HbE genes were heterozygous (AE). Differences in HbE prevalence among the studied ethnic groups indirectly documents that ancestries and evolutionary forces, such as drift and admixture, are the important factors in the persistence of HbE distribution in northern Thailand. Furthermore, the presence of HbE in groups of northern Thailand had no effect on the in vitro infectivity and proliferation of Plasmodium falciparum, nor the production of hemozoin, a heme crystal produced by malaria parasites, when compared to normal red-blood-cell controls. Our data may contribute to a better understanding on the persistence of HbE among ethnic groups and its association with malaria.

Hemoglobin H disease (Hb H) arises through the loss or dysfunction of three of the four alpha globin genes through the co-inheritance of either gross gene deletions or an abnormal hemoglobin which causes a non-deletional loss of α-globin expression. This study sought to investigate erythropoiesis in Hb H-Constant Spring (Hb H-CS) disease, a common form of Hb H disease in Southeast Asia, caused by the inheritance of the Constant Spring variant hemoglobin together with deletion of two of the alpha globin genes. In comparison to normal erythroblasts, Hb H-CS erythroblasts showed reduced cell expansion although no difference in differentiation was observed. Proteomic analysis revealed the increased expression of both chaperone and chaperonin proteins as well as down regulation of proteins regulating apoptosis. Both chaperone and chaperonin mediated folding require ATP, and evidence of increase energy demand was seen in the form of increased expression of enzymes involved in purine biosynthesis and increased levels of reactive oxygen species. A significant increase in apoptosis was seen in Hb H-CS erythroblasts, and the results from the proteomic analysis suggest that this arises at least in part from the consequences of increased folding requirements in the Hb H-CS erythroblast., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Erythropoiesis in β0-thalassaemia/Hb E patients, the most common variant form of β-thalassaemia in Southeast Asia, is characterized by accelerated differentiation and over-expansion of erythroid precursor cells. The mechanism driving this accelerated expansion and differentiation remain unknown. To address this issue a proteomic analysis was undertaken to firstly identify proteins differentially expressed during erythroblast differentiation and a second analysis was undertaken to identify proteins differentially expressed between β0-thalassaemia/Hb E erythroblasts and control erythroblasts. The majority of proteins identified as being differentially expressed between β0-thalassaemia/Hb E and control erythroblasts were constituents of the glycolysis/TCA pathway and levels of oxidative stress correlated with the degree of erythroid expansion. A model was constructed linking these observations with previous studies showing increased phosphorylation of ERK1/2 in thalassemic erythroblasts which predicted the increased activation of PKA, PKB and PKC which Western analysis confirmed. Inhibition of PKA or PKC reduced β0-thalassaemia/Hb E erythroblast differentiation and/or expansion. We propose that increased expansion and differentiation of β0-thalassaemia/Hb E erythroblasts occur as a result of feedback loops acting through increased oxidative metabolism., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Cells respond to stress stimuli through a number of response pathways, of which one of the most important and well characterized is the unfolded protein response. Despite a large body of work which suggests that stress in erythroblasts may play a pivotal role in the pathogenesis of beta-thalassemia/Hb E disease, this pathway remains uninvestigated., Design and Methods: Day 10 erythroblasts from normal controls and beta-thalassemia/Hb E patients were subjected to internal (treatment with tunicamycin) and external (serum and growth factor withdrawal) stress stimuli and the activation of the unfolded protein response pathway was investigated., Results: Normal erythroblasts responded to both internal and external stress by activating the unfolded protein response (UPR) pathway while in contrast, erythroblasts from beta-thalassemia/Hb E patients only showed activation of the unfolded protein response pathway in response to internal stress. This was reflected by a markedly increased induction of apoptosis in serum and growth factor deprived beta-thalassemia/Hb E erythroblasts as compared to control cells. Modulation of the levels of intracellular Ca(2+) in thalassemic erythroblasts restored UPR activation during serum deprivation and significantly reduced the level of serum deprivation induced apoptosis to control levels., Conclusions: These results suggest the failure of thalassemic erythroblasts to cope with cellular stress caused by an impaired UPR function as a result of high Ca(2+) levels may exacerbate thalassemic cell death during erythropoiesis.

Beta-thalassaemia is one of the most common inherited anaemias, arising from a partial or complete loss of beta-globin chain synthesis. In severe cases, marked bone marrow erythroid hyperplasia, believed to result from erythropoietin (EPO)-mediated feedback from the anaemic condition is common, however, as yet, no study has investigated EPO-mediated signal transduction in thalassaemic erythroid cells. Using proerythroblasts generated from peripheral blood circulating CD34+ haematopoietic progenitor cells, the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinases (MAPK/ERKs) pathway was examined under conditions of steady state growth, cytokine deprivation and post-EPO stimulation. Levels of cellular cyclic adenosine monophosphate (cAMP) and Ca2+ were determined as was the degree of erythroid expansion. A significantly higher basal level of phosphorylation of ERK1/2 was observed in beta-thalassaemia/Hb E proerythroblasts as compared to normal controls, which was coupled with significantly higher levels of both cAMP and Ca2+. Modulation of either cAMP or Ca2+ or direct inhibition of MAPK/ERK kinase (MEK) reduced basal levels of ERK1/2 phosphorylation, as well as significantly reducing the level of erythroid expansion. These results suggest that, in contrast to current models, hyper proliferation of beta-thalassaemia/Hb E proerythroblasts is an intrinsic process driven by higher basal levels of ERK1/2 phosphorylation resulting from deregulation of levels of cAMP and Ca2+.