Reticulocyte hemoglobin content associated with the risk of iron deficiency anemia

Background/Objective

Reticulocyte hemoglobin content (MCHr) was recognized as a rapid and reliable marker for investigating iron deficiency (ID). We hypothesized that MCHr was associated with the risk of iron deficiency anemia in adults.

Methods

This is a dual-center case-control study. A total of 806 patients and healthy individuals were recruited from Ruijin Hospital and Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine between January 2021 and December 2021. The participants were categorized into iron deficiency anemia (IDA) group (n = 302), non-IDA group (n = 366), and healthy control group (n = 138). According to the MCHr level, the participants were divided into two groups, i.e. normal MCHr (≥25 pg) and decreased MCHr (<25 pg) group. Multivariate logistic regression analysis and adjusted subgroup analysis were conducted to estimate the relative risk between MCHr and IDA, with confounding factors including age, sex, hemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), Hematocrit (HCT), serum iron (Fe), ferritin (Ferrit), and total iron binding capacity (TIBC).

Results

Compared with the non-IDA, the MCHr level with IDA decreased significantly. ROC curve analysis showed that MCHr had the largest area under the AUC curve. After comprehensive adjustment for confounding factors, individuals with normal level of MCHr exhibited a decreased risk of IDA (OR = 0.68 [0.60, 0.77], P < 0.01), while the risk of IDA was up to 5 times higher for those with decreased MCHr.

Conclusion

Our findings supported the hypothesis that MCHr was associated with the risk of IDA in adults and could serve as an indicator of IDA severity. MCHr holds clinical value as an auxiliary diagnostic indicator, providing valuable insights into whether invasive examinations are warranted in the assessment of IDA.

Effect of Reduced INR in Early Pregnancy on the Occurrence of Preeclampsia: A Retrospective Cohort Study

To investigate the effect of reduced early-pregnancy activated partial thrombin time (APTT), prothrombin time (PT), and international standardized ratio (INR) on the risk of preeclampsia. A total of 8549 pregnant women with singleton births were included. Early pregnancy APTT, PT, and INR levels, with age, birth, prepregnancy body mass index, fibrinogen (FBG), thrombin time (TT), D-dimer (DD2), antithrombin III (ATIII), fibrin degradation products (FDP) as confounders, generalized linear model of APTT, the relative risk of PT and INR when INR reduction. After adequate adjustment for confounders, the relative risk of preeclampsia was 0.703 for every 1 s increase in plasma PT results in early pregnancy, and for every 0.1 increase in plasma INR results, the relative risk of preeclampsia was 0.767. With a PT less than the P25 quantile (<11 s), the relative risk of preeclampsia was 1.328. The relative risk of preeclampsia at an INR less than the P25 quantile (<0.92) was 1.24. There was no statistical association between APTT on the risk of preeclampsia. The relative risk of preeclampsia is strongly associated with a decrease in PT and INR in early pregnancy. PT and INR in early pregnancy were a potential marker in the risk stratification of preeclampsia. Focusing on reduced PT and INR levels in early pregnancy can help to identify early pregnancies at risk for preeclampsia.

Investigation of the relationship between changes in maternal coagulation profile in the first trimester and the risk of developing preeclampsia

Normal pregnancy is a hypercoagulable state with an increase in coagulation factor levels and a decrease in natural anticoagulation. However, a higher hypercoagulable state with prolonged activated partial thromboplastin time (APTT), prothrombin time (PT), increased D-dimer, and mean platelet volume is seen in women with preeclampsia at the time of onset. In addition, endothelial dysfunction occurs before the clinical symptoms of preeclampsia. Therefore, we undertook this study to investigate the coagulation profile in the first trimester in women who developed preeclampsia later. A total of 853 pregnant women with singleton births at the Obstetrics and Gynecology Hospital of Fudan University between January 2021 and December 2021 were included in this case-control study. In the comparison with the controls (n = 531), the mean value of D-dimer, APTT, thrombin time (TT), antithrombin (AT)), and fibrin degradation products (FDP) was significantly lower in preeclamptic women at the time of diagnosis (n = 322). The changes in the coagulation profile were not associated with the severity or the time of onset. The reduced values of D-dimer, AT, and FDP, and increased values of TT were also observed in the first trimester in women who developed preeclampsia later and were not associated with the severity, or the time of onset of preeclampsia. After adjusting for maternal age and BMI, the values of D-dimer and AT in the first trimester were correlated to the risk of developing preeclampsia. Our findings suggest that there is an abnormal maternal response to the hemostatic system in early gestational age in women who developed preeclampsia later and measuring the coagulation profile could be an additional predictive marker of preeclampsia.

Identification of the ataxin-1 interaction network and its impact on spinocerebellar ataxia type 1

Background

Spinocerebellar ataxia type 1 (SCA1) is a neurodegenerative disease caused by a polyglutamine expansion in the ataxin-1 protein. The pathogenic mechanism resulting in SCA1 is still unclear. Protein–protein interactions affect the function and stability of ataxin-1.

Methods

Wild-type and mutant ataxin-1 were expressed in HEK-293T cells. The levels of expression were assessed using real-time polymerase chain reaction (PCR) and Western blots. Co-immunoprecipitation was done in HEK-293T cells expressing exogenous wild-type and mutant ataxin-1 using anti-Flag antibody following by tandem affinity purification in order to study protein–protein interactions. The candidate interacting proteins were validated by immunoprecipitation. Chromatin immunoprecipitation and high-throughput sequencing and RNA immunoprecipitation and high-throughput sequencing were performed using HEK-293T cells expressing wild-type or mutant ataxin-1.

Results

In this study using HEK-293T cells, we found that wild-type ataxin-1 interacted with MCM2, GNAS, and TMEM206, while mutant ataxin-1 lost its interaction with MCM2, GNAS, and TMEM206. Two ataxin-1 binding targets containing the core GGAG or AAAT were identified in HEK-293T cells using ChIP-seq. Gene Ontology analysis of the top ataxin-1 binding genes identified SLC6A15, NTF3, KCNC3, and DNAJC6 as functional genes in neurons in vitro. Ataxin-1 also was identified as an RNA-binding protein in HEK-293T cells using RIP-seq, but the polyglutamine expansion in the ataxin-1 had no direct effects on the RNA-binding activity of ataxin-1.

Conclusions

An expanded polyglutamine tract in ataxin-1 might interfere with protein–protein or protein–DNA interactions but had little effect on protein–RNA interactions. This study suggested that the dysfunction of protein–protein or protein–DNA interactions is involved in the pathogenesis of SCA1.

Reversal of the Apoptotic Resistance of Non-Small-Cell Lung Carcinoma towards TRAIL by Natural Product Toosendanin

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively triggers cancer cell death via its association with death receptors on the cell membrane, but exerts negligible side effects on normal cells. However, some non-small-cell lung carcinoma (NSCLC) patients exhibited resistance to TRAIL treatment in clinical trials, and the mechanism varies. In this study, we described for the first time that toosendanin (TSN), a triterpenoid derivative used in Chinese medicine for pain management, could significantly sensitize human primary NSCLC cells or NSCLC cell lines to TRAIL-mediated apoptosis both in vitro and in vivo, while showing low toxicity against human primary cells or tissues. The underlying apoptotic mechanisms involved upregulation of death receptor 5 (DR5) and CCAAT/enhancer binding protein homologous protein, which is related to the endoplasmic reticulum stress response, and is further associated with reactive oxygen species generation and Ca²⁺ accumulation. Surprisingly, TSN also induced autophagy in NSCLC cells, which recruited membrane DR5, and subsequently antagonized the apoptosis-sensitizing effect of TSN. Taken together, TSN can be used to sensitize tumors and the combination of TRAIL and TSN may represent a useful strategy for NSCLC therapy; moreover, autophagy serves as an important drug resistance mechanism for TSN.

Persistency of Enlarged Autolysosomes Underscores Nanoparticle-Induced Autophagy in Hepatocytes

The diverse biological effects of nanomaterials form the basis for their applications in biomedicine but also cause safety issues. Induction of autophagy is a cellular response after nanoparticles exposure. It may be beneficial in some circumstances, yet autophagy-mediated toxicity raises an alarming concern. Previously, it has been reported that upconversion nanoparticles (UCNs) elicit liver damage, with autophagy contributing most of this toxicity. However, the detailed mechanism is unclear. This study reveals persistent presence of enlarged autolysosomes in hepatocytes after exposure to UCNs and SiO₂ nanoparticles both in vitro and in vivo. This phenomenon is due to anomaly in the autophagy termination process named autophagic lysosome reformation (ALR). Phosphatidylinositol 4-phosphate (PI(4)P) relocates onto autolysosome membrane, which is a key event of ALR. PI(4)P is then converted into phosphatidylinositol 4,5-bisphosphate (PI(4,5)P₂ ) by phosphatidylinositol-4-phosphate 5-kinase. Clathrin is subsequently recruited by PI(4,5)P₂ and leads to tubule budding of ALR. Yet it is observed that PI(4)P cannot be converted in nanoparticle-treated hepatocytes cells. Exogenous supplement of PI(4,5)P₂ suppresses the enlarged autolysosomes in vitro. Abolishment of these enlarged autolysosomes by autophagy inhibitor relieves the hepatotoxicity of UCNs in vivo. The results provide evidence for disrupted ALR in nanoparticle-treated hepatocytes, suggesting that the termination of nanoparticle-induced autophagy is of equal importance as the initiation.

Giant Cellular Vacuoles Induced by Rare Earth Oxide Nanoparticles are Abnormally Enlarged Endo/Lysosomes and Promote mTOR-Dependent TFEB Nucleus Translocation

Many nanomaterials are reported to disrupt lysosomal function and homeostasis, but how cells sense and then respond to nanomaterial-elicited lysosome stress is poorly understood. Nucleus translocation of transcription factor EB (TFEB) plays critical roles in lysosome biogenesis following lysosome stress induced by starvation. The authors previously reported massive cellular vacuolization, along with autophagy induction, in cells treated with rare earth oxide (REO) nanoparticles. Here, the authors identify these giant cellular vacuoles as abnormally enlarged and alkalinized endo/lysosomes whose formation is dependent on macropinocytosis. This vacuolization causes deactivation of mammalian target of rapamycin (mTOR), a TFEB-interacting kinase that resides on the lysosome membrane. Subsequently, TFEB is dephosphorylated at serine 142 and translocated into cell nucleus. This nucleus translocation of TFEB is observed only in vacuolated cells and it is critical for maintaining lysosome homeostasis after REO nanoparticle treatment, as knock-down of TFEB gene significantly compromises lysosome function and enhances cell death in nanoparticle-treated cells. Our results reveal that cellular vacuolization, which is commonly observed in cells treated with REOs and other nanomaterials, represents a condition of profound lysosome stress, and cells sense and respond to this stress by facilitating mTOR-dependent TFEB nucleus translocation in an effort to restore lysosome homeostasis.

[Relationship between decreased expression of inhibin B and spermatogenesis dysfunction in rats testis]

Objective: To explore the effects of varicocele on the expressions of inhibin B in rat testes and the relationship between expression of inhibin B and spermatogenesis dysfunction. Methods: Twenty specific-pathogen-free Sprague-Dawley (SD) male rats were randomly divided into two groups with random number table: 4-week control group (C4) and 4-week experimental group(V4). Experimental varicocele was created by partial ligation of left renal vein in the V4 group; vein isolation without ligation was performed in the C4 group.Spermatogenetic function in the two groups were assessed. The expression of inhibin B in the rat testis was analyzed by immunohistochemistry, the expressions of inhibin B, Fas and Fas ligand(FasL)mRNA measured by reverse transcription-polymerase chain reaction(RT-PCR), and the inhibin B protein expression by Western blot. Results: In comparison of spermatogenetic function in left rat testes, the Johnsen scores in the V4 group were significantly lower than those in the C4 group (9.79±0.05 vs 9.97±0.02, P=0.023), the seminiferous epithelium in the V4 group was significantly thinner than that in the C4 group [(48.35±0.99)μm vs (57.58±1.98)μm, P=0.000], and the number of sperms in the left epididymis was significantly lower than in the right one in the V4 group [(933±161)×10⁶/(ml·g) vs(1 552±184)×10⁶/(ml·g), P=0.017]. Both Western blot and immunohistochemical assay showed that the expression of inhibin B in the rat testes was significantly lower in the V4 group than in the C4 group(0.407±0.053 vs 0.608±0.076, P=0.038; 0.161±0.004 vs 0.183±0.005, P=0.008). RT-PCR also detected reduced expression of inhibin B mRNA in the V4 group compared with the C4 group(0.522±0.050 vs 1.106±0.210, P=0.003. Compared to the C4 group, the expression of Fas mRNA in the V4 group was significantly lower, while the expression of FasL mRNA in the V4 group was significantly higher(P=0.019, 0.015). Conclusions: Varicocele can lead to decreased expressions of inhibin B in rat testes and cause spermatogenesis dysfunction. There may be a close correlation between down-regulation ofinhibin B expression and spermatogenesis dysfunction.Inhibin B may play a significant rolein the mechanisms underlying male infertility due to varicocele.

Differential ERK activation during autophagy induced by europium hydroxide nanorods and trehalose: Maximum clearance of huntingtin aggregates through combined treatment

Accelerating the clearance of intracellular protein aggregates through elevation of autophagy represents a viable approach for the treatment of neurodegenerative diseases. In our earlier report, we have demonstrated the enhanced degradation of mutant huntingtin protein aggregates through autophagy process induced by europium hydroxide nanorods [EHNs: Eu(III)(OH)3], but the underlying molecular mechanism of EHNs mediated autophagy was unclear. The present report reveals that EHNs induced autophagy does not follow the classical AKT-mTOR and AMPK signaling pathways. The inhibition of ERK1/2 phosphorylation using the specific MEK inhibitor U0126 partially abrogates the autophagy as well as the clearance of mutant huntingtin protein aggregates mediated by EHNs suggesting that nanorods stimulate the activation of MEK/ERK1/2 signaling pathway during autophagy process. In contrast, another mTOR-independent autophagy inducer trehalose has been found to induce autophagy without activating ERK1/2 signaling pathway. Interestingly, the combined treatment of EHNs and trehalose leads to more degradation of mutant huntingtin protein aggregates than that obtained with single treatment of either nanorods or trehalose. Our results demonstrate the rational that further enhanced clearance of intracellular protein aggregates, needed for diverse neurodegenerative diseases, may be achieved through the combined treatment of two or more autophagy inducers, which stimulate autophagy through different signaling pathways.

Transdermal delivery of human epidermal growth factor facilitated by a peptide chaperon

Peptide chaperon TD1 was discovered to facilitate several proteins' transdermal delivery via topical co-administration. To design a practical, safe system for advanced transdermal peptide, a novel method was carried out. Human epidermal growth factor (hEGF) was selected as the model biological agent and a fusion protein: TD1-hEGF was designed. Study showed that TD1-hEGF not only had the similar bioactivity with native hEGF, but also possessed considerable higher transdermal ability than hEGF and a co-administration of TD1 and hEGF. These results provided convincing evidence for the advantages of TD1-hEGF in cosmetic and medical applications. Moreover, the fusion pattern between the cargoes and TD1 offered a new approach to facilitate other hydrophilic drugs' transdermal delivery for therapeutic application.

Ser234Leu missense mutation in the A1 domain of factor V causing moderate factor V deficiency in a Chinese family

AIMS

To investigate the molecular defects in a Chinese pedigree with inherited factor V (FV) deficiency.

METHODS

Laboratory studies including activated partial thromboplastin time (APTT), prothrombin (PT), and thrombin time (TT) were tested in a patient and his family members. FV antigen (FV:Ag) and FV activity (FV:C) were measured by both ELISA and one-stage clotting assays. All the exons, exon-intron boundaries and promoter regions of FV gene were analysed by direct sequencing. The detected mutations were introduced independently by site-directed mutagenesis into a pMT2/FV mammalian expression plasmid containing the full-length FV cDNA and the wild-type and mutant FV proteins were expressed in COS-7 and CHO cells.

RESULTS

The proposita, a 52-year-old Chinese man, had no spontaneous bleeding syndrome. It was found that he had prolonged APTT and PT, 52 s and 22.8 s, respectively, a FV:C of 5.5% and a FV:Ag of 33.1%. Gene analysis showed the proposita was a compound heterozygote of FV mutations, carrying Ser234Leu and Arg413Cys. The FV antigen and activity levels of the Ser234Leu and Arg413Cys mutants are lower than wild type both in cell lysates and in culture media. Protein degradation inhibitor experiment in transfected COS-7 cells showed that Ser234Leu and Arg413Cys degraded intracellularly through the lysosomal pathway. CHO cells expressing either the wild-type or the mutant FV were subjected to immunofluorescence staining with the indicated antibodies and organelle markers, indicating that Ser234Leu and Arg413Cys can be transported to Golgi partially.

CONCLUSIONS

We identified the molecular pathological mechanism of the novel C785T mutation causing type I inherited FV deficiency for the first time.

MR molecular imaging of thrombus: development and application of a Gd-based novel contrast agent targeting to P-selectin

Molecular imaging of thrombus formation at initial stage requires a robust thrombus-specific contrast agent with high sensitivity. In this study, we report a novel P-selectin-targeted paramagnetic molecular imaging agent and the agent's potential to sensitively detect occult microthrombi on the intimal surface of endothelium. Platelet clots and blood clots targeted in vitro with paramagnetic nanoparticles presented a highly detectable, homogeneous T1-weighted contrast enhancement that was improved with increasing gadolinium level. In vivo contrast enhancement under part of circulation conditions was assessed in dogs. The micro-thrombi around the femoral vein of dog demonstrated higher signal intensities than the control clots and the adjacent muscle. Histology was performed on regions likely to contain thrombus as indicated by MRI. These results suggest that molecular imaging of P-selectin-targeted paramagnetic nanoparticles can provide sensitive detection and localization of P-selectin and may allow for early, direct identification of microthrombi, leading to early diagnosis.

[Molecular mechanisms of Glanzmann thrombasthenia caused by alpha II b L721R and Q860X compound heterozygous mutation]

OBJECTIVE

To explore the molecular mechanisms of Glanzmann thrombasthenia caused by alpha II b L721R and Q860X compound heterozygous mutation.

METHODS

All exons and exon-intron boundaries of alpha II b and beta3 gene were amplified by PCR and analyzed by direct DNA sequencing. Gene polymorphisms were excluded by direct DNA sequencing. Alpha II b L721R and Q860X mutants expressing vectors were constructed by in vitro site-directed mutagenesis. The expression of alpha II b L721R and Q860X mutants on transfected cell membrane were analyzed by flow cytometry and the whole expression level was confirmed by Western blot. The subcellular localizations of alpha II b L721R and Q860X mutants were determined by immunofluorescent confocal scanning microscopy.

RESULTS

The alpha II b compound heterozygous mutations, T2255G (L721R) and C2671T (Q860X), were identified in the proband, the former being inherited from the maternal side and the latter the paternal side. The 293T cells cotransfected with mutated alpha II b L721R and wild-type beta3 expression plasmids expressed 2.1% of normal amount of alpha II b on the cell surface as shown by FACS, in contrast to 31.9% of normal amount of alpha II b on the cells cotransfected with cDNAs of mutated alpha II b Q860X and wildtype beta3 expression plasmids. Western blot of the cell lysates showed no detectable mature alpha II b in cells lysates with L721R mutant. While, truncated alpha II b protein was detected in cell lystes with Q860X mutant. Immunofluorescence studies demonstrated that both L721R and Q860X mutant pro-alpha II bbeta33 complex colocalized in endoplasmic reticulum, but a little in Golgi.

CONCLUSIONS

The L721R and Q860X mutations of alpha II b prevent transport of the pro-alpha II bbeta3 complex from the endoplasmic reticulum to the Golgi, hindering its maturation and surface expression. The impaired alpha II bbeta3 transport is responsible for the thrombasthenia.

[Analysis of clinical features and genotype in three Chinese pedigrees with Glanzmann thrombasthenia]

OBJECTIVE

To study the clinical feature and alpha II b beta 3 gene mutations of three Glanzmann thrombasthenia (GT) pedigrees.

METHODS

Platelet counts (BPC), blood film, bleeding time, platelet aggregation and flow cytometry were used for phenotype diagnosis of all the patients. All the exons of alpha II b and beta 3 genes were amplified by polymerase chain reaction (PCR) and direct sequencing was performed for mutational screening. One hundred and three healthy blood donors were as normal controls.

RESULTS

Three probands showed normal BPC, defective platelets aggregation, prolonged bleeding time and significantly reduced platelet aggregation to ADP, epinephrine, and collagen, while relatively normal aggregation to ristocetin. Flow cytometry showed platelet surface expressed alpha II b beta 3 was strongly reduced in proband 1 and proband 3 and mildly reduced in the amount of surface expressed alpha II b beta 3 (63%) in proband 2. Sequencing results showed that proband 1 had a G10A homozygous mutation in alpha II b, and a G1412T homozygous mutation in beta3. Compound heterozygous mutations in beta3, G1199A and 1525delC were identified in proband 2. No mutations in alpha II b beta 3 gene were identified in proband 3.

CONCLUSIONS

Compound homozygous mutations, GI0A in alpha II b and G1412T in beta3, lead to GT in proband 1. Compound heterozygous mutations in beta3, G1199A and 1525delC, lead to GT in proband 2. The mutations of G10A, G1412T and 1525delC were reported for the first time in GT patients.

[Antithrombin deficiency due to heterozygous antithrombin gene mutation and a pedigree study]

OBJECTIVE

To identify the antithrombin (AT) phenotype and gene mutation of a kindred with hereditary antithrombin deficiency.

METHODS

Plasma AT activity and AT antigen level of the propositus and his kindred members were determined with chromogenic substrate method and immunoassay, respectively. All the seven exons and intron-exon boundaries of antithrombin gene were analyzed by PCR and direct sequencing of amplified PCR products from the propositus.

RESULTS

The propositus AT antigen level was normal but his AT activity was only 65% of normal value suggesting that he had type II AT deficiency. A heterozygous G13830A mutation in exon 6 resulting in Arg393His missense mutation in his AT polypeptide was identified in the propositus. The same phenotype and gene mutation were found in other 3 kindred members.

CONCLUSION

The type II AT deficiency found in this kindred is caused by heterozygous G13830A mutation in AT gene.

[The related analysis of venous thromboembolism and cSNPs of coagulation factor V gene]

OBJECTIVE

To identify the relationship between coagulation factor V (FV) gene single nucleotide polymorphisms (SNPs) and venous thromboembolism (VTE).

METHODS

The FV clotting activity (FV: C) and FV antigen (FV: Ag) in plasma of VTE group (111 patients) and normal control (110 patients) were detected using one-stage clotting assay and ELISA, respectively. Five pairs of primers of the F V polymorphisms including Asp79His, Arg306The, Arg306Gly, Arg506Gln and Ile359The/His1299 Arg were synthesized and amplified by PCR. The PCR products were digested by restriction enzyme using PCR-RFLP. The detected polymorphisms were confirmed by direct sequencing. The samples containing the polymorphisms were screened for coding regions of all F V exons with direct sequencing.

RESULTS

The plasma levels of F V: C and F V: Ag of VTE group and normal control were (106.9 +/- 28.0)%, (110.4 +/- 33.3)% and (102.4 +/- 30.9)%, (102.1 +/- 24.1)%, respectively. The plasma level of FV: Ag was significantly different between VTE group and normal control. However, there was no difference in F V: C levels. Polymorphisms for the fore mentioned 5 primer pairs were not found in either patients or normal controls. Polymorphism of His1299Arg was identified in 5 patients with VTE and 3 normal controls. And these 5 cases also combined Met1736Val polymorphism, 3 of them combined another Asp2194Gly polymorphism.

CONCLUSION

The higher plasma level of F V: Ag contribute to venous thromboembolism. There is no relationship between polymorphisms of Asp79His, Arg306The, Arg306Gly, Arg506Gln, Ile359The and venous thromboembolism in Chinese studied. Polymorphism His1299Arg is higher in VTE group than in normal control, but has no statistical difference. Polymorphisms of His1299Arg, Met1736Val and Asp2194Gly are linked disequilibrium in Chinese Han population.