BACKGROUND:Platelet-derived extracellular vesicles are the most abundant vesicles in the circulation,rich in bioactive molecules,genetic material,proteins and other information molecules,involved in cellular communication and material exchange,not only has good procoagulant activity,but also has the promotion of tissue repair and regeneration,and has a wide range of applications in regenerative medicine. OBJECTIVE:To elaborate the secretion mechanism of platelet-derived extracellular vesicles,their application in regenerative medicine,and limiting factors for clinical transformation,and to provide some theoretical support for the clinical translation of platelet-derived extracellular vesicles. METHODS:A computerized search of the PubMed database from January 2005 to August 2023 was applied to articles relating to platelet-derived extracellular vesicles with the search terms"platelet-derived,platelet-rich plasma,extracellular vesicles,isolated,microvesicles exosomes,applications".A total of 62 articles that met the subject criteria were finally included. RESULTS AND CONCLUSION:(1)Activated platelet-derived extracellular vesicles produce two types of vesicles,platelet-derived microparticles,whose secretion may be associated with the asymmetry of the actin cytoskeleton,and platelet-derived exosomes,which may be associated with the regulation of H+-ATPase.(2)Platelet-derived extracellular vesicles are potential effectors of platelet concentrates and platelets themselves,and may intervene in tissue regeneration by promoting angiogenesis,influencing cellular behavior,promoting coagulation and hemostasis,and exerting inflammatory effects.(3)Platelet-derived extracellular vesicles have been reported preclinically in the field of regenerative medicine such as tissue injury,muscle regeneration,cartilage regeneration,and osteoarthritis,and clinical trial data are available as potential therapeutic approaches for wound healing.However,factors such as isolation methods,sample sources,and the types of activators limit the clinical translation of platelet-derived extracellular vesicles into the field of regenerative medicine.(4)In the future,platelet-derived extracellular vesicles may become a cell-free alternative to platelet-rich plasma in regenerative medicine,but the clinical translation of platelet-derived extracellular vesicles needs to actively search for specific markers to differentiate platelet-derived microparticles from platelet-derived exosomes.The mechanism of activator-stimulated platelet-derived extracellular vesicle production,as well as the optimal method of platelet-derived extracellular vesicle collection,the optimal method of storage,the shelf life of the platelet-derived extracellular vesicles,the recommended dosage of platelet-derived extracellular vesicles for clinical application,and the optimal clinical indications need to be further investigated.

BACKGROUND:Clinical application of autologous platelet-rich plasma is limited by the condition of patients and by the quantity and activity of platelets.Transfusable platelet component blood platelet concentrates,collected and prepared by blood collection and supply agencies,are widely available,can be standardized and are effective in the clinic. OBJECTIVE:To review the factors influencing the preparation of platelet concentrate by the buffy-coat method for the treatment of chronic refractory wounds. METHODS:A computer search of the PubMed,CNKI,and WanFang databases for platelet-related articles from January 2000 to April 2023 was conducted using the Chinese and English search terms"allogeneic platelets(concentrate),buffy-coat method,skin ulcer,refractory wounds".The titles and abstracts were screened,and the full text was reviewed,resulting in the inclusion of 51 articles that met the subject criteria. RESULTS AND CONCLUSION:(1)Platelet concentrates supplied by blood collection and supply agencies are effective in the treatment of diabetic foot wounds,pressure sores,lower limb venous ulcers and other chronic refractory wounds:reducing the size of the ulcer and shortening the wound healing time,especially in the first two weeks,with significant healing-promoting effects.(2)The storage conditions of the raw material used to prepare platelet concentrates(whole blood overnight/buffy-coat overnight,shaking/resting(time)),centrifugation conditions(centrifugation parameters,canning method)and the structure of the blood bag can affect the concentration of platelet concentrates,indirectly affecting the efficacy of allogeneic platelet concentrates.(3)There are also some problems with studies of allogeneic platelet concentrates for the treatment of chronic refractory wounds,such as the sample size of the available evidence is small,the results lack the optimal preparation parameters,optimal dose and treatment regimen for platelet concentrates to promote healing of different wounds are unknown,so more randomized multicenter clinical studies are needed.

Objective:To investigate the regulatory role of RNA m 6A methyltransferase (METTL14) in ultraviolet B (UVB) radiation-induced skin injury, and to preliminarily explore the potential of targeted inhibition of METTL14 for treating UVB-induced skin injury. Methods:A UVB radiation-induced skin injury model was established by exposing C57BL/6J mice to 150 mJ/cm 2 UVB, and was assessed and scored with HE staining and Masson staining. UVB radiation-induced cell injury models were established by exposing human immortalized keratinocytes (HaCaT) and human skin fibroblasts (WS1) to 10 and 30 mJ/cm 2 UVB, respectively. The m 6A levels in the mouse skin and cell models after UVB exposure were quantified by colorimetric assay, and m 6A-related enzymes in cells were measured by Western blot. HaCaT and WS1 cell lines overexpressing METTL14 were constructed using recombinant adenoviral vectors, and the overexpression effects were tested by Western blot. The METTL14 overexpression cells were examined for their m 6A levels, proliferative abilities after UVB exposure (by clone formation assay), and changes in apoptosis (by flow cytometry). The model mice with UVB-induced skin injury in the treatment groups received subcutaneous injection of the METTL14 inhibitor S-adenosylhomocysteine (SAH) solution (1 mg/kg, 5 mg/kg) twice consecutively before and after irradiation; and the mice were assessed and scored for skin injury with HE staining and Masson staining. Results:On the 4th day after 150 mJ/cm 2 UVB irradiation, the mice showed remarkable skin injury, pathologically featuring inflammatory infiltration, tissue structure disorganization, and collagen fiber degradation, reaching the maximum score; and the m 6A level in the skin was significantly downregulated ( t = 3.07, P < 0.05). At 24 h after 10 and 30 mJ/cm 2 irradiation, HaCaT and WS1 cells showed significantly reduced survival rates ( t = 7.64, 7.15, P < 0.05), significantly downregulated m 6A levels ( t = 4.78, 4.36, P <0.05), and significantly time-dependent downregulation of METTL14 protein expression ( t = 6.39, 4.76, P < 0.05). In HaCaT and WS1 cells, METTL14 overexpression significantly up-regulated m 6A levels ( t = 7.66, 3.67, P < 0.05), significantly inhibited the clone-forming ability of cells after UVB irradiation ( t = 6.29, 3.84, P < 0.05), and significantly increased the rate of cell apoptosis ( t = 3.48, 9.54, P < 0.05). Compared with those in the normal saline group, the model mice with UVB-induced skin injury in the SAH treatment group (5 mg/kg) showed significantly decreased pathological scores of skin injury ( t = 3.21, 4.27, 5.81, P < 0.05), with milder inflammatory infiltration, more orderly tissue structure, and less collagen fiber degradation. Conclusions:METTL14 can increase the sensitivity of skin cells to UVB radiation, and targeted inhibition of METTL14 can effectively alleviate UVB radiation-induced skin injury, which may be a potential new target for the treatment of UVB radiation-induced skin injury.

Radon, the only natural radioactive gas, is also a primary source of natural radiation for human beings. Studies have revealed its diverse biological effects on the human body. This paper presents a summary of domestic and internal studies on radon conducted in recent years, organizing its impacts on various organs of the human body, along with their mechanisms and medical applications. Accordingly, novel reflections are proposed. This review aims to provide a theoretical basis for the in-depth interdisciplinary exploration into the impacts of radon on human health and their mechanisms in the future, holding great significance for preventing radon′s hazards and promoting its beneficial applications.

Objective To investigate the mechanism of Chonghe soft extract on ulcer wound healing in diabetic rats through protein kinase B(Akt)/mammalian Sirolimus target protein(mTOR)-mediated nucleotides binding oligomeric acid domain-like receptor protein 3(NLRP3)inflammasome inactivation.Methods Thirty six SD rats with diabetic ulcer,which were established by feeding with high glucose and high fat diet and injecting intraperitoneally with streptozocin(STZ)combined with skin defect,were randomly divided into model group,Chonghe soft extract group and growth factor group,with twelve rats in each group.Another twelve SD rats were injected an equal dose of citric acid-sodium citrate buffer solution and used as blank group.The blank group and the model group were not received drug intervention,but the Chonghe soft extract group and the growth factor group were externally applied Chonghe soft extract and growth factor gel,respectively.The wound healing of each group was observed and recorded.After 7 days and 14 days of treatment,the histopathology of wound were observed by HE staining and the number of fibroblasts were counted.The levels of IL-1β,IL-18 and TNF-α in serum were detected by ELISA.The expression of autophagy-related protein Beclin-1 and LC3Ⅱ in granulation tissue was detected by immunohistochemistry.The expression of NLRP3,apoptosis-associated speck-like protein containing a caspase recruitment domain(ASC),Caspase1,Pro-Caspase1 and Akt/mTOR autophagy pathway-related proteins Akt,p-Akt,mTOR and p-mTOR were detected by Western Blot.Results Compared with the blank control group,the pathological wound repair of the model group was delayed on the 7th day and 14th day,the number of fibroblasts per unit area was decreased(P<0.01).The levels of IL-1β,IL-18 and TNF-α were increased(P<0.01).The expression levels of ASC,Pro-Caspase1,Caspase1,and NLRP3 were increased in the wound tissues(P<0.01),while the expression levels of Beclin-1,LC3-Ⅱ,mTOR,p-mTOR,Akt and p-Akt were decreased in the wound tissues(P<0.01).Compared with the model group,the pathological injury in Chonghe soft extract group and growth factor group was significantly improved on the 7th day and 14th day.The number of fibroblasts per unit area was significantly increased(P<0.01).The levels of IL-1β,IL-18 and TNF-α were significantly decreased(P<0.01).The expression levels of ASC,Pro-Caspase1,Caspase1,and NLRP3 in the wound tissues were decreased(P<0.01),while the expression levels of Beclin-1,LC3-Ⅱ,mTOR,p-mTOR,Akt and p-Akt were increased(P<0.01,P<0.05).Conclusion Chonghe soft extract can reduce inflammatory reaction,promote the generation of fibro,regulate the Akt/mTOR-mediated NLRP3 inflammasome inactivation,improve the level of autophagy in wound,and promote ulcer wound healing in diabetic rats.

Objective: To explore the microbial correlation between oral tongue coating (TC) and gastric mucosa (GM) in patients with gastric intestinal metaplasia (GIM). Methods: The present study recruited 1360 volunteers for upper gastrointestinal cancer screening. The microbiota in TC and GM were profiled by long-read sequencing of full-length 16S rRNA gene. The microbial diversity, community structure, and linear discriminant analysis effect size (LEfSe) were analyzed by the software Visual Genomics. SparCC correlation analysis was used to construct the commensal network and the graphical display was conducted by R software. Results: The population included 44 patients with precancerous GIM, and 28 matched controls with negative rapid urease test (RUT) and non-symptomatic chronic superficial gastritis (CSG). No significant difference in diversity was observed between GIM patients and controls in TC or GM microbiota (P > 0.05). Patients had a higher percentage of 41 – 60 co-occurring operational taxonomic units (OTUs) between TC and GM than controls (34.1% vs. 25.0%) (P < 0.05). The LEfSe showed that TC Prevotella melaninogenica and three gastric Helicobacter species (i.e., Helicobacter pylori, Helicobacter pylori XZ274, and Helicobacter pylori 83) were enriched in patients with GIM. Furthermore, GIM patients with positive RUT had a lower percentage of co-occurring OTUs over 20 (P < 0.05), and lower abundances of gastric Veillonella, Pseudonocardia, and Mesorhizobium than those with negative RUT (P < 0.05). The commensal network between TC and GM was more complex in GIM patients than in controls. GIM patients with positive RUT demonstrated more bacterial correlations between TC and GM than those with negative RUT. Finally, the serum ratio of PG-I/II was negatively correlated with three gastric Helicobacter species (Helicobacter pylori, Helicobacter pylori XZ274, and Helicobacter pylori 83) in patients with negative RUT (P < 0.05), and negatively correlated with two TC species (Fusobacterium nucleatum subsp. nucleatum and Campylobacter showae) in patients with positive RUT (P < 0.05). Conclusion The development of GIM potentiated the commensal network between oral TC and GM, providing microbial evidence of the correlation between TC and the stomach.

Objective:To investigate the effects and mechanisms of copper transporter 1 (CTR1) in radiation induced intestinal injury in vitro. Methods:Human small intestinal epithelial cells (HIEC) were irradiated with 2, 4, 6, 8 Gy of X-rays and rat intestinal epithelial cells (IEC-6) were irradiated with 5, 10, 15, 20 Gy of X-rays. At 2, 4, 8, 24, and 48 h after irradiation, the expression of CTR1 was detected by Western blot assay. In some experiments, HIEC and IEC-6 cells were transfected with CTR1 shRNA and then exposed to X-rays. Copper levels were detected by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The radiosensitivity of cells was verified by colonogenic assay, the cellular reactive oxygen species (ROS) level and DNA damage were detected to further explore the related mechanism. In addition, Western blot was applied to detect the expressions of antioxidants and cuproptosis associated proteins in enterocytes after silencing CTR1 or irradiation.Results:The expression of CTR1 was increased by X-ray irradiation in a dose-dependent manner ( t=3.53, 3.45, 6.37, 11.11, 11.13, P<0.05). CTR1 expression was successfully diminished by CTR1 shRNA adenovirus vectors. According to the survival curves, the enhancement ratios of the radiosensitivity of HIEC and IEC-6 cells with CTR1 knocking-down were 1.146 and 1.201, respectively. Radiation-induced copper accumulation was alleviated after CTR1 silencing in IEC-6 cells ( t=3.10, P<0.05). At 0.5 h after irradiation, the ROS production in the CTR1 knockdown group was significantly lower than that in the control group ( t=5.23, 2.96, P<0.05). At 1 h after irradiation, the protein expression of γ-H2AX in the CTR1 knockdown group was obviously lower than that in the control group ( t=7.50, 4.29, P<0.05). The expressions of Nrf2 and HO-1 were increased after irradiation, which could be further increased after CTR1 silencing. In addition, cuproptosis associated protein DLAT, LIAS and FDX1 were reduced post-irradiation, which were recovered after CTR1 silencing. Conclusions:The radioresistance of HIEC and IEC-6 cells was enhanced after CTR1 silencing, possibly through the intracellular ROS and cuproptosis pathway.

N 6-methyladenosine (m 6A) is the most abundant epigenetic modification in eukaryotic messenger RNA (mRNA), which could be catalyzed by m 6A methyltransferase (Writers), recognized by methylation recognition enzymes (Readers), and removed by demethylase (Erasers). RNA splicing, translation, and stability could be modulated by m 6A methylation modification. The m 6A methylation modification is involved in the biological regulation of a variety of important functional genes in cellular activities. Importantly, abnormal m 6A modification affects the occurrence, development, metastasis and recurrence of tumors. Ionizing radiation can affect the level of m 6A and m 6A methylation-related enzymes. Recently, m 6A methylation is reported to regulate the efficacy of tumor radiotherapy by affecting DNA damage and radiosensitivity of tumor cells. In addition, ionizing radiation can also affect the level of m 6A modification in normal cells to regulate the progress of radiation-induced injuries. This review summarizes the research progress on the roles of m 6A methylation in tumor radiosensitivity and radiation-induced injuries, with the aim of providing novel strategies for the development of clinical tumor radiosensitizers and radioprotective agents.

Ketone bodies have beneficial metabolic activities, and the induction of plasma ketone bodies is a health promotion strategy. Dietary supplementation of sodium butyrate (SB) is an effective approach in the induction of plasma ketone bodies. However, the cellular and molecular mechanisms are unknown. In this study, SB was found to enhance the catalytic activity of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2), a rate-limiting enzyme in ketogenesis, to promote ketone body production in hepatocytes. SB administrated by gavage or intraperitoneal injection significantly induced blood ß-hydroxybutyrate (BHB) in mice. BHB production was induced in the primary hepatocytes by SB. Protein succinylation was altered by SB in the liver tissues with down-regulation in 58 proteins and up-regulation in 26 proteins in the proteomics analysis. However, the alteration was mostly observed in mitochondrial proteins with 41% down- and 65% up-regulation, respectively. Succinylation status of HMGCS2 protein was altered by a reduction at two sites (K221 and K358) without a change in the protein level. The SB effect was significantly reduced by a SIRT5 inhibitor and in Sirt5-KO mice. The data suggests that SB activated HMGCS2 through SIRT5-mediated desuccinylation for ketone body production by the liver. The effect was not associated with an elevation in NAD⁺/NADH ratio according to our metabolomics analysis. The data provide a novel molecular mechanism for SB activity in the induction of ketone body production.
Mice ; Animals ; Butyric Acid/metabolism* ; Ketone Bodies/metabolism* ; Liver/metabolism* ; Hydroxybutyrates/metabolism* ; Down-Regulation ; Sirtuins/metabolism* ; Hydroxymethylglutaryl-CoA Synthase/metabolism*

Different degrees of visual function impairment is the main reason for first visit of children with optic pathway glioma; it seriously affects the quality of life of children. Early diagnosis, timely treatment, maximum preservation or restoration of the children's vision function, and improvement of quality of life of children are major challenges. This article reviews the recent advance in visual function assessments for children with optic pathway glioma, aiming to provide some references for early clinical objective assessment of visual function impairment and clear diagnosis.