A novel human specific lncRNA MEK6-AS1 regulates adipogenesis and fatty acid biosynthesis by stabilizing MEK6 mRNA.

Obesity is becoming one of the major non-communicable diseases with increasing incidence and risks that cannot be ignored. However effective and safe clinical treatment strategies still need to be deeply explored. Increased number and volume of adipocytes lead to overweight and obesity. The aim of our work is to identify lncRNAs that have important regulatory in differentiation of human mesenchymal stem cells (MSCs) into adipocytes, and to provide effective targets for clinical prevention and treatment of obesity and related metabolic disorders. We extracted primary MSCs from human adipose tissue, and conducted expression profile analysis of lncRNAs during adipogenic differentiation of MSCs to screen changed lncRNAs. Characteristics of lncRNA were revealed mainly by RACE and RNA FISH. Loss- and gain-of function experiments in vivo and in vitro were used to analyze effects of lncRNA. Targeted metabolomics was utilized to detect levels of free fatty acids. RNA pull-down, mRNA stability tests, etc. were employed to explore mechanisms of lncRNA. Human-specific lncRNA, we named it MEK6-AS1, was the most up-regulated transcript during adipogenic differentiation of MSCs. MEK6-AS1 was highly expressed in adipose tissue samples from individuals with BMI ≥ 25 and positively correlated with adipogenic marker genes in these samples. Knocking down lncRNA inhibited expression of adipogenic differentiation markers and ectopic adipogenesis, reducing contents of various free fatty acids, as well as promoting osteogenic differentiation. Overexpression of lncRNA had the opposite effects to the above processes. We also found that MEK6-AS1 was elevated during hepatic steatosis organoid generation. Mechanistically, MEK6-AS1 worked partially through stabilization of MEK6 mRNA by NAT10. We have identified a human-specific lncRNA (MEK6-AS1) with position information in the genomic database but has not been extensively reported. We demonstrated that MEK6-AS1 as a novel lncRNA involved in adipogenic differentiation and adipogenesis, fatty acid metabolism, and osteogenic differentiation. We found that MEK6-AS1 may exert its effect by enhancing MEK6 mRNA stability through NAT10. Our study may provide insights into implication of lncRNAs in stem cell biology and offer a new potential therapeutic target for the prevention and treatment of obesity and other related disease.

被引量：- 发表：1970

CCL5 is essential for axonogenesis and neuronal restoration after brain injury.

被引量：- 发表：1970

Decreased plasma gelsolin fosters a fibrotic tumor microenvironment and promotes chemoradiotherapy resistance in esophageal squamous cell carcinoma.

Stromal fibrosis is highly associated with therapeutic resistance and poor survival in esophageal squamous cell carcinoma (ESCC) patients. Low expression of plasma gelsolin (pGSN), a serum abundant protein, has been found to correlate with inflammation and fibrosis. Here, we evaluated pGSN expression in patients with different stages of cancer and therapeutic responses, and delineated the molecular mechanisms involved to gain insight into therapeutic strategies for ESCC. Circulating pGSN level in ESCC patients was determined by enzyme-linked immunosorbent assay analysis, and the tissue microarray of tumors was analyzed by immunohistochemistry staining. Cell-based studies were performed to investigate cancer behaviors and molecular mechanisms, and mouse models were used to examine the pGSN-induced tumor suppressive effects in vivo. Circulating pGSN expression is distinctively decreased during ESCC progression, and low pGSN expression correlates with poor therapeutic responses and poor survival. Methylation-specific PCR analysis confirmed that decreased pGSN expression is partly attributed to the hypermethylation of the GSN promoter, the gene encoding pGSN. Importantly, cell-based immunoprecipitation and protein stability assays demonstrated that pGSN competes with oncogenic tenascin-C (TNC) for the binding and degradation of integrin αvβ3, revealing that decreased pGSN expression leads to the promotion of oncogenic signaling transduction in cancer cells and fibroblasts. Furthermore, overexpression of pGSN caused the attenuation of TNC expression and inactivation of cancer-associated fibroblast (CAF), thereby leading to tumor growth inhibition in mice. Our results demonstrated that GSN methylation causes decreased secretion of pGSN, leading to integrin dysregulation, oncogenic TNC activation, and CAF formation. These findings highlight the role of pGSN in therapeutic resistance and the fibrotic tumor microenvironment of ESCC.

被引量：- 发表：1970

Current landscape of mRNA technologies and delivery systems for new modality therapeutics.

Realizing the immense clinical potential of mRNA-based drugs will require continued development of methods to safely deliver the bioactive agents with high efficiency and without triggering side effects. In this regard, lipid nanoparticles have been successfully utilized to improve mRNA delivery and protect the cargo from extracellular degradation. Encapsulation in lipid nanoparticles was an essential factor in the successful clinical application of mRNA vaccines, which conclusively demonstrated the technology's potential to yield approved medicines. In this review, we begin by describing current advances in mRNA modifications, design of novel lipids and development of lipid nanoparticle components for mRNA-based drugs. Then, we summarize key points pertaining to preclinical and clinical development of mRNA therapeutics. Finally, we cover topics related to targeted delivery systems, including endosomal escape and targeting of immune cells, tumors and organs for use with mRNA vaccines and new treatment modalities for human diseases.

被引量：- 发表：1970

Neuroprotective effects of intranasal extracellular vesicles from human platelet concentrates supernatants in traumatic brain injury and Parkinson's disease models.

The burgeoning field of regenerative medicine has significantly advanced with recent findings on biotherapies using human platelet lysates (HPLs), derived from clinical-grade platelet concentrates (PCs), for treating brain disorders. These developments have opened new translational research avenues to explore the neuroprotective effects of platelet-extracellular vesicles (PEVs). Their potential in managing neurodegenerative conditions like traumatic brain injury (TBI) and Parkinson's disease (PD) warrants further exploration. We aimed here to characterize the composition of a PEV preparation isolated from platelet concentrate (PC) supernatant, and determine its neuroprotective potential and neurorestorative effects in cellular and animal models of TBI and PD. We isolated PEVs from the supernatant of clinical-grade PC collected from healthy blood donors utilizing high-speed centrifugation. PEVs were characterized by biophysical, biochemical, microscopic, and LC-MS/MS proteomics methods to unveil biological functions. Their functionality was assessed in vitro using SH-SY5Y neuronal cells, LUHMES dopaminergic neurons, and BV-2 microglial cells, and in vivo by intranasal administration in a controlled cortical impact (CCI)-TBI model using 8-weeks-old male C57/BL6 mice, and in a PD model induced by MPTP in 5-month-old male C57/BL6 mice. PEVs varied in size from 50 to 350 nm, predominantly around 200 nm, with concentrations ranging between 1010 and 1011/mL. They expressed specific platelet membrane markers, exhibited a lipid bilayer by cryo-electron microscopy and, importantly, showed low expression of pro-coagulant phosphatidylserine. LC-MS/MS indicated a rich composition of trophic factors, including neurotrophins, anti-inflammatory agents, neurotransmitters, and antioxidants, unveiling their multifaceted biological functions. PEVs aided in the restoration of neuronal functions in SH-SY5Y cells and demonstrated remarkable neuroprotective capabilities against erastin-induced ferroptosis in dopaminergic neurons. In microglial cells, they promoted anti-inflammatory responses, particularly under inflammatory conditions. In vivo, intranasally delivered PEVs showed strong anti-inflammatory effects in a TBI mouse model and conserved tyrosine hydroxylase expression of dopaminergic neurons of the substantia nigra in a PD model, leading to improved motor function. The potential of PEV-based therapies in neuroprotection opens new therapeutic avenues for neurodegenerative disorders. The study advocates for clinical trials to establish the efficacy of PEV-based biotherapies in neuroregenerative medicine.

被引量：- 发表：1970