Dynamic palmitoylation of STX11 controls injury-induced fatty acid uptake to promote muscle regeneration.

Different types of cells uptake fatty acids in response to different stimuli or physiological conditions; however, little is known about context-specific regulation of fatty acid uptake. Here, we show that muscle injury induces fatty acid uptake in muscle stem cells (MuSCs) to promote their proliferation and muscle regeneration. In humans and mice, fatty acids are mobilized after muscle injury. Through CD36, fatty acids function as both fuels and growth signals to promote MuSC proliferation. Mechanistically, injury triggers the translocation of CD36 in MuSCs, which relies on dynamic palmitoylation of STX11. Palmitoylation facilitates the formation of STX11/SNAP23/VAMP4 SANRE complex, which stimulates the fusion of CD36- and STX11-containing vesicles. Restricting fatty acid supply, blocking fatty acid uptake, or inhibiting STX11 palmitoylation attenuates muscle regeneration in mice. Our studies have identified a critical role of fatty acids in muscle regeneration and shed light on context-specific regulation of fatty acid sensing and uptake.

Effects of paternal exposure to cigarette smoke on sperm DNA methylation and long-term metabolic syndrome in offspring.

BACKGROUND: Although paternal exposure to cigarette smoke may contribute to obesity and metabolic syndrome in offspring, the underlying mechanisms remain uncertain. METHODS: In the present study, we analyzed the sperm DNA-methylation profiles in tobacco-smoking normozoospermic (SN) men, non-tobacco-smoking normozoospermic (N) men, and non-smoking oligoasthenozoospermic (OA) men. Using a mouse model, we also analyzed global methylation and differentially methylated regions (DMRs) of the DLK1 gene in paternal spermatozoa and the livers of progeny. In addition, we quantified DLK1 expression, executed an intra-peritoneal glucose tolerance test (IPGTT), measured serum metabolites, and analyzed liver lipid accumulation in the F1 offspring. RESULTS: Global sperm DNA-methylation levels were significantly elevated (p < 0.05) in the SN group, and the methylation patterns were different among N, SN, and OA groups. Importantly, the methylation level of the DLK1 locus (cg11193865) was significantly elevated in the SN group compared to both N and OA groups (p < 0.001). In the mouse model, the group exposed to cigarette smoke extract (CSE) exhibited a significantly higher global methylation DNA level in spermatozoa (p < 0.001) and on the DMR sites of Dlk1 in 10-week-old male offspring (p < 0.05), with a significant increase in Dlk1 expression in their livers (p < 0.001). In addition, IPGTT and LDL levels were significantly altered (p < 0.001), with elevated liver fat accumulation (p < 0.05) in F1 offspring. CONCLUSION: Paternal exposure to cigarette smoke led to increased global methylation of sperm DNA and alterations to the DMR of the DLK1 gene in the F1 generation, which may be inherited parentally and may perturb long-term metabolic function.

Behavioral changes and brain epigenetic alterations induced by maternal deficiencies of B vitamins in a mouse model.

RATIONALE: B vitamins play essential roles in brain development and functionality; however, the effects of their deficiency during early life on mental health are not thoroughly understood. OBJECTIVES: The objective of this study is to investigate the effects of a maternal deficiency of vitamin B6, B9 (folate), and B12 on behavioral changes in adult offspring. METHODS: Female C57BL/6 J mice were put on a diet lacking vitamin B6, B9, B12, or the above three vitamins from pregnancy to weaning. The growth and developmental characteristics of both the pregnant mothers and offspring were collected. In the adult offspring, the serum levels of neuroactive substances were measured using an enzyme-linked immunosorbent assay. The level of BDNF and dimethylated lysine 9 on histone H3 (H3K9me2) was detected by immunohistochemical staining. In addition, their depressive-like behaviors, anxiety-like behaviors, and sociability were recorded using sucrose preference, a forced swim, social interaction, tail suspension, and open field tests. RESULTS: The maternal deficiency of the three B vitamins delayed offspring development. Compared to the controls, all of the groups showed decreased serum levels of 5-HT and neuropeptide Y. In the groups with deficiency of B9 or the three B vitamins, there were significant changes in sociability and social novelty preference. In groups with deficiencies in B9, B12, or all three B vitamins, the expression levels of BDNF and H3K9me2 in the hippocampus were significantly decreased. CONCLUSIONS: Maternal deficiencies of the major B vitamins caused changes in social behaviors in adult mice accompanied with epigenetic alterations in the brain and changes in the serum levels of neuroactive substances.

MicroRNA-2355-5p regulates γ-globin expression in human erythroid cells by inhibiting KLF6.

Krüppel-like factors (KLFs) are a highly conserved family of transcription factors. We analysed expression profile data of KLFs and identified KLF6 as a new potential regulator of erythropoiesis. Knocking down the expression of KLF6 significantly raised γ-globin mRNA and protein levels in the erythroid cell line HUDEP-2 and haematopoietic progenitor (CD34+ ) cells. We found that overexpression of microRNA (miR)-2355-5p in HUDEP-2 and CD34+ cells correlated with increased γ-globin synthesis by suppressing expression of KLF6. Our discovery that the interaction between miR-2355-5p and KLF6 affects the expression of γ-globin may provide more information for the clinical management of ß-thalassaemia patients.

Serum miRNA biomarker discovery for placenta accreta spectrum.

Placenta accreta spectrum (PAS) disorder is a major cause of maternal and fetal morbidity, and in vitro biomarkers are highly desired in clinic. This study enrolled three phases of 186 pregnant women, including controls, PAS patients, placenta previa (PP) patients, and pre-eclamptic (PE) patients. Initial miRNA array screened 42 out of 768 serum miRNAs in the screening phase, and then validated four miRNAs by quantitative RT-PCR in the training phase and validation phase. Their performance for PAS prenatal screening was analyzed by the receiver operating characteristic (ROC) curve, sensitivity, and specificity. Data validated that four miRNAs (miR-139-3p, miR-196a-5p, miR-518a-3p, and miR-671-3p) were down-regulated in PAS group comparing with controls in three phases of subjects. Except for miR-518a-3p, the expression levels of these miRNAs also were significantly different between the PAS and the group including PP and PE. In addition, these biomarkers demonstrated modest screening efficiency, as the AUC ranged from 0.59 to 0.74, sensitivity 0.54 to 0.80, and specificity 0.62 to 0.76. However, the AUC and specificity can improve greatly (AUC 0.91, specificity 0.92) using a 'diagnostic signature' that combined the four miRNAs and four clinical parameters into one panel. GO and KEGG signaling pathway analysis indicated their target genes were involved in angiogenesis, embryonic development, cell migration and adhesion, and tumor-related pathways. In conclusion, the four miRNAs discovered in this study not only can be used for future non-invasive prenatal PAS screening, but also provide a new experimental basis for future research on PAS etiology.

Unusual survival of a twin with homozygous α0-thalassemia due to Chimerism.

Not available.

Thalassaemia intermedia caused by coinheritance of a ß-thalassaemia mutation and a de novo duplication of α-globin genes in the paternal allele.

Next generation sequencing identified a de novo, 204 kb, tandem duplication (αααα204 ) in the α-globin gene cluster of a Chinese thalassaemia intermedia patient. Haplotype analysis showed that the duplicated chromosome was of paternal origin. Molecular analysis of genomic DNA from the patient's lymphocytes, hair follicles, buccal mucosa cells, his father's lymphocytes and sperm cells excluded the possibility of somatic or germinal mosaicism. The analysis also indicated that this duplication arose during spermatogenesis. The microhomology in the breakpoint was found and suggested that this duplication could be formed by a coupled homologous and non-homologous recombination mechanism.

A novel 223 kb deletion in the beta-globin gene cluster was identified in a Chinese thalassemia major patient.

INTRODUCTION: Although mutations in the human beta-globin gene cluster are essentially point mutations, several large deletions have been described in recent years. METHODS: We have identified a novel 223 kb deletion in a Chinese patient by multiplex ligation-dependent probe amplification and characterized it by next-generation sequencing, Gap-PCR, and DNA sequence analysis. RESULTS: The deletion extends from the 3'UTR of the δ globin gene (HBD) to 215 kb downstream of the HBB. Compound heterozygous with the typical ß-thalassemia-CD41-42(-CTTT) mutation, the proband presented with microcytosis and hypochromic red cells, and required regulate transfusion. The patient was clinically diagnosed with thalassemia major. CONCLUSION: Our study widens the mutation spectrum of ß-thalassemia. In addition, this case may spark future studies of the regulatory regions of the beta-globin gene cluster.

Polysaccharide extracted from Chinese white wax scale ameliorates 2,4-dinitrochlorobenzene-induced atopic dermatitis-like symptoms in BALB/c mice.

Atopic dermatitis (AD) is a common inflammatory skin disease with high rates of morbidity and is associated with erythema, pruritus, scaling of affected areas of skin. It is extremely important to introduce a therapeutic agent which has significant anti-inflammatory effect with less side-effect for treatment of AD. This study evaluated the effect of a natural compound from herbal extracts, the crude polysaccharide extracted from the white wax scale (CWPS), on AD-like mice. Repeated applications of 2,4-dinitrochlorobenzene (DNCB) were performed on ear and dorsal skin of BALB/c mice to induce AD-like symptoms and skin lesions. Oral administration of CWPS decreased serum IgE level and limited the infiltration of mast cells and eosinophils to the dermal tissues in the DNCB-induced AD mice. In addition, CWPS reduced Th1 and Th17 responses, leading to an attenuated cutaneous inflammatory response. Furthermore, in vitro study also demonstrated that CWPS limited T cell activation and cytokines (i.e. IFN-γ and IL-17) production induced by DNCB. We conclude that CWPS attenuates DNCB-induced AD-like skin lesion through modulating T cell-elicited immune responses and CD4+ T cell polarization, and could be exploited as a new therapeutic approach for AD.