Epigenetic targeting of autophagy for cancer: DNA and RNA methylation.

Autophagy, a crucial cellular mechanism responsible for degradation and recycling of intracellular components, is modulated by an intricate network of molecular signals. Its paradoxical involvement in oncogenesis, acting as both a tumor suppressor and promoter, has been underscored in recent studies. Central to this regulatory network are the epigenetic modifications of DNA and RNA methylation, notably the presence of N6-methyldeoxyadenosine (6mA) in genomic DNA and N6-methyladenosine (m6A) in eukaryotic mRNA. The 6mA modification in genomic DNA adds an extra dimension of epigenetic regulation, potentially impacting the transcriptional dynamics of genes linked to autophagy and, especially, cancer. Conversely, m6A modification, governed by methyltransferases and demethylases, influences mRNA stability, processing, and translation, affecting genes central to autophagic pathways. As we delve deeper into the complexities of autophagy regulation, the importance of these methylation modifications grows more evident. The interplay of 6mA, m6A, and autophagy points to a layered regulatory mechanism, illuminating cellular reactions to a range of conditions. This review delves into the nexus between DNA 6mA and RNA m6A methylation and their influence on autophagy in cancer contexts. By closely examining these epigenetic markers, we underscore their promise as therapeutic avenues, suggesting novel approaches for cancer intervention through autophagy modulation.

Research Progress on the Regulation of Autophagy and Apoptosis in Insects by Sterol Hormone 20-Hydroxyecdysone.

20E (20-Hydroxyecdysone) is a central steroid hormone that orchestrates developmental changes and metamorphosis in arthropods. While its molecular mechanisms have been recognized for some time, detailed elucidation has primarily emerged in the past decade. PCD (Programmed cell death), including apoptosis, necrosis, efferocytosis, pyroptosis, ferroptosis, and autophagy, plays a crucial role in regulated cell elimination, which is vital for cells' development and tissue homeostasis. This review summarizes recent findings on 20E signaling regulated autophagy and apoptosis in insects, including Drosophila melanogaster, Bombyx mori, Helicoverpa armigera, and other species. Firstly, we comprehensively explore the biosynthesis of the sterol hormone 20E and its subsequent signal transduction in various species. Then, we focus on the involvement of 20E in regulating autophagy and apoptosis, elucidating its roles in both developmental contexts and bacterial infection scenarios. Furthermore, our discussion unfolds as a panoramic exposition, where we delve into the fundamental questions with our findings, anchoring them within the grander scheme of our study in insects. Deepening the understanding of 20E-autophagy/apoptosis axis not only underscores the intricate tapestry of endocrine networks, but also offers fresh perspectives on the adaptive mechanisms that have evolved in the face of environmental challenges.

Protein modification regulated autophagy in Bombyx mori and Drosophila melanogaster.

Post-translational modifications refer to the chemical alterations of proteins following their biosynthesis, leading to changes in protein properties. These modifications, which encompass acetylation, phosphorylation, methylation, SUMOylation, ubiquitination, and others, are pivotal in a myriad of cellular functions. Macroautophagy, also known as autophagy, is a major degradation of intracellular components to cope with stress conditions and strictly regulated by nutrient depletion, insulin signaling, and energy production in mammals. Intriguingly, in insects, 20-hydroxyecdysone signaling predominantly stimulates the expression of most autophagy-related genes while concurrently inhibiting mTOR activity, thereby initiating autophagy. In this review, we will outline post-translational modification-regulated autophagy in insects, including Bombyx mori and Drosophila melanogaster, in brief. A more profound understanding of the biological significance of post-translational modifications in autophagy machinery not only unveils novel opportunities for autophagy intervention strategies but also illuminates their potential roles in development, cell differentiation, and the process of learning and memory processes in both insects and mammals.

PFN2a Suppresses C2C12 Myogenic Development by Inhibiting Proliferation and Promoting Apoptosis via the p53 Pathway.

Skeletal muscle plays a crucial role in physical activity and in regulating body energy and protein balance. Myoblast proliferation, differentiation, and apoptosis are indispensable processes for myoblast myogenesis. Profilin 2a (PFN2a) is a ubiquitous actin monomer-binding protein and promotes lung cancer growth and metastasis through suppressing the nuclear localization of histone deacetylase 1 (HDAC1). However, how PFN2a regulates myoblast myogenic development is still not clear. We constructed a C2C12 mouse myoblast cell line overexpressing PFN2a. The CRISPR/Cas9 system was used to study the function of PFN2a in C2C12 myogenic development. We find that PFN2a suppresses proliferation and promotes apoptosis and consequentially downregulates C2C12 myogenic development. The suppression of PFN2a also decreases the amount of HDAC1 in the nucleus and increases the protein level of p53 during C2C12 myogenic development. Therefore, we propose that PFN2a suppresses C2C12 myogenic development via the p53 pathway. Si-p53 (siRNA-p53) reverses the PFN2a inhibitory effect on C2C12 proliferation and the PFN2a promotion effect on C2C12 apoptosis, and then attenuates the suppression of PFN2a on myogenic differentiation. Our results expand understanding of PFN2a regulatory mechanisms in myogenic development and suggest potential therapeutic targets for muscle atrophy-related diseases.

MiR-501-3p Forms a Feedback Loop with FOS, MDFI, and MyoD to Regulate C2C12 Myogenesis.

Skeletal muscle plays an essential role in maintaining body energy homeostasis and body flexibility. Loss of muscle mass leads to slower wound healing and recovery from illness, physical disability, poor quality of life, and higher health care costs. So, it is critical for us to understand the mechanism of skeletal muscle myogenic differentiation for maintaining optimal health throughout life. miR-501-3p is a novel muscle-specific miRNA, and its regulation mechanism on myoblast myogenic differentiation is still not clear. We demonstrated that FOS was a direct target gene of miR-501-3p, and MyoD regulated miR-501-3p host gene Clcn5 through bioinformatics prediction. Our previous laboratory experiment found that MDFI overexpression promoted C2C12 myogenic differentiation and MyoD expression. The database also showed there is an FOS binding site in the MDFI promoter region. Therefore, we hypothesize that miR-501-3p formed a feedback loop with FOS, MDFI, and MyoD to regulate myoblast differentiation. To validate our hypothesis, we demonstrated miR-501-3p function in the proliferation and differentiation period of C2C12 cells by transfecting cells with miR-501-3p mimic and inhibitor. Then, we confirmed there is a direct regulatory relationship between miR-501-3p and FOS, MyoD and miR-501-3p, FOS and MDFI through QPCR, dual-luciferase reporter system, and ChIP experiments. Our results not only expand our understanding of the muscle myogenic development mechanism in which miRNA and genes participate in controlling skeletal muscle development, but also provide treatment strategies for skeletal muscle or metabolic-related diseases in the future.

MiR-27b Promotes Muscle Development by Inhibiting MDFI Expression.

BACKGROUND/AIMS: Skeletal muscle plays an essential role in the body movement. However, injuries to the skeletal muscle are common. Lifelong maintenance of skeletal muscle function largely depends on preserving the regenerative capacity of muscle. Muscle satellite cells proliferation, differentiation, and myoblast fusion play an important role in muscle regeneration after injury. Therefore, understanding of the mechanisms associated with muscle development during muscle regeneration is essential for devising the alternative treatments for muscle injury in the future. METHODS: Edu staining, qRT-PCR and western blot were used to evaluate the miR-27b effects on pig muscle satellite cells (PSCs) proliferation and differentiation in vitro. Then, we used bioinformatics analysis and dual-luciferase reporter assay to predict and confirm the miR-27b target gene. Finally, we elucidate the target gene function on muscle development in vitro and in vivo through Edu staining, qRT-PCR, western blot, H&E staining and morphological observation. RESULT: miR-27b inhibits PSCs proliferation and promotes PSCs differentiation. And the miR-27b target gene, MDFI, promotes PSCs proliferation and inhibits PSCs differentiation in vitro. Furthermore, interfering MDFI expression promotes mice muscle regeneration after injury. CONCLUSION: our results conclude that miR-27b promotes PSCs myogenesis by targeting MDFI. These results expand our understanding of muscle development mechanism in which miRNAs and genes work collaboratively in regulating skeletal muscle development. Furthermore, this finding has implications for obtaining the alternative treatments for patients with the muscle injury.

MiR-34c represses muscle development by forming a regulatory loop with Notch1.

Since pork accounts for about 40% of global meat consumption, the pig is an important economic animal for meat production. Pig is also a useful medical model for humans due to its similarity in size and physiology. Understanding the mechanism of muscle development has great implication for animal breeding and human health. Previous studies showed porcine muscle satellite cells (PSCs) are important for postnatal skeletal muscle growth, and Notch1 signaling pathway and miRNAs regulate the skeletal muscle development. Notch1 signal pathway regulates the transcription of certain types of miRNAs which further affects target gene expression. However, the specific relationship between Notch1 and miRNAs during muscle development has not been established. We found miR-34c is decreased in PSCs overexpressed N1ICD. Through the overexpression and inhibition of mi-34c, we demonstrated that miR-34c inhibits PSCs proliferation and promotes PSCs differentiation. Using dual-luciferase reporter assay and Chromatin immunoprecipitation, we demonstrate there is a reciprocal regulatory loop between Notch1 and miR-34c. Furthermore, injection of miR-34c lentivirus into mice caused repression of gastrocnemius muscle development. In summary, our data revealed that miR-34c can form a regulatory loop with Notch1 to repress muscle development, and this result expands our understanding of muscle development mechanism.

Novel antiviral effect of lithium chloride on mammalian orthoreoviruses in vitro.

Reovirus not only causes considerable economic loss in the swine industry of the United States and other countries, but also threatens the public health due to its zoonotic potential. According to previous reports, LiCl has antiviral activity against a number of viruses. The inhibitory effects of LiCl on reovirus life cycle in Vero cells were evaluated. The unpaired t-test and one-way ANOVA were used to analyze the differences between experimental groups. We first found that LiCl treatment significantly inhibited reovirus replication in a dose-dependent manner. Furthermore, we found that this antiviral activity of LiCl targets the early stage of viral replication. LiCl could be a potential drug against reovirus infection.

[Hydrogen sulfide removal by the combination of non-thermal plasma and biological process].

A bench scale system integrating a non-thermal plasma (NTP) unit with a biotricking filtration (BTF) unit for the treatment of gases containing hydrogen sulfide (H2S) was investigated. The additional use of the biotrickling filter to NTP reactor not only leads to the enhancement of hydrogen sulfide removal efficiency up from 83.4% to 90.1%, but also eliminates gas-phase intermediate products from NTP degradation of H2S to produce sulfate and H2O. The dynamic changes of microbial community in BTF influenced by ozone from NTP were assessed by PCR-DGGE. Results show that the microbial community was affected by ozone. After the integration, a part of microorganisms disappeared, and meanwhile some new microorganisms appeared. The microbial community structure in BTF changed from eight bands to nine bands; three bands which have the functions of desulfurization disappeared and four bands which have the functions of desulfurization appeared; five bands which have the functions of desulfurization and sulfate reduction were unchanged. The bacterial groups in the BTF unit of NTP-BTF system include Uncultured Thiobacillus sp., Acidithiobacillus thiooxidans strain dfI, Uncultured Thiobacillus sp., Uncultured Acidiphilium sp., Uncultured Xanthomonadaceae bacterium clone SBLE6C12, Uncultured 8-Proteobacterium and Paracraurococcus sp. 1PNM-27.

[Mechanism and performance of a membrane bioreactor for treatment of toluene vapors].

The performance of a membrane bioreactor for treatment of toluene as a model pollutant is presented. Effects of toluene inlet concentration, residence time, spray density and pH of liquid phase on the toluene removal rate were evaluated. The experimental results showed that the toluene removal efficiency reached 99%. The optimal pH, residence time and spray density were 7.2, 6.4 s and 2.5 m3 x (m2 x h)(-1), respectively. The gas-phase biodegradation intermediate products were acetaldehyde acid (C2H2O3) and vinyl formic acid (C3H4O2), which were identified by means of gas chromatography/mass spectrometry (GC/MS). The mechanism of toluene degradation using a membrane bioreactor can be described as the combination of mass transfer from hollow fiber membrane to biofilm and biological degradation. Toluene (C6H5CH3) and oxygen diffused from the gas phase to the wet layer of the biofilm and were then consumed by the microbial communities. Toluene was oxidized to the intermediate organic products such as acetaldehyde acid (C2H2O3) and vinyl formic acid (C3H4O2), and the intermediate products were then converted to CO2 and H2O through continuous biological oxidation reactions.

[Decreased mRNA expressions of T-type channel alpha1H and alpha1G in the sperm of varicocele patients and their implication].

OBJECTIVE: To study the relationship of varicocele (VC) with the expressions of T-type channel alpha1H and alpha1G in the sperm of VC patients. METHODS: Based on the WHO criteria, we examined the semen samples by computer-aided sperm analysis (CASA), and divided the samples into groups A (normal semen from volunteers, n = 20), B (normal semen from VC patients, n = 16) and C (abnormal semen from VC patients, n = 44). We optimized the semen by discontinuous Percoll grade centrifugation, and determined the mRNA expressions of T-type channel alpha1H and alpha1G in the three groups using using reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Compared with group A, the mRNA expressions of alpha1H and alpha1G showed with no significant decrease in group B (P>0.05), but were remarkably reduced in group C (P<0.01). CONCLUSION: The abnormal mRNA expressions of T-type channel alpha1H and alpha1G may be one of the causes of declined semen quality and consequently infertility in VC patients, which has pointed out a new direction for the studies of the causes and treatment of VC-related infertility.

[Treatment of delayed complex malhealed jaw fractures in 32 patients.].

PURPOSE: Three methods were used to manage delayed complex malhealed jaw fractures in 32 patients. The indication for each method and final result was evaluated. METHODS: Three methods included conservative therapy, internal fixation and orthognathic surgery. In conservative therapy, intermaxillary fixation was obtained with dental arch splints. In internal fixation, ordinary operation was performed including open exposure of the fractured segments, anatomical reposition and rigid fixation with steel wire or titanium miniplates. In some patients, orthognathic surgery was carried out with intermaxillary ligation for 2 to 3 weeks postoperatively. RESULTS: All the wounds healed primarily without significant complications. The postoperative occlusion and appearance were satisfactory or fair. CONCLUSIONS: The selection of treatment methods should be based on the location, time, severity of the fracture and the patients' age, in order to achieve maximal recovery of mastication and appearance.