N⁶-methyladenosine (m⁶A) is a ubiquitous RNA modification in mammals. This modification is "written" by methyltransferases and then "read" by m⁶A-binding proteins, followed by a series of regulation, such as alternative splicing, translation, RNA stability, and RNA translocation. At last, the modification is "erased" by demethylases. m⁶A modification is essential for normal physiological processes in mammals and is also a very important epigenetic modification in the development of cancer. In recent years, cancer-related m⁶A regulation has been widely studied, and various mechanisms of m⁶A regulation in cancer have also been recognized. In this review, we summarize the changes of m⁶A modification in prostate cancer and discuss the effect of m⁶A regulation on prostate cancer progression, aiming to profile the potential relevance between m⁶A regulation and prostate cancer development. Intensive studies on m⁶A regulation in prostate cancer may uncover the potential role of m⁶A methylation in the cancer diagnosis and cancer therapy.
Animals ; Male ; Humans ; Methylation ; Adenosine/metabolism* ; RNA/metabolism* ; Methyltransferases/metabolism* ; Prostatic Neoplasms ; Mammals

Objective To observe the effect of excess oxygen supply for different time periods on the mitochondrial energy metabolism in alveolar epithelial type Ⅱ cells. Methods Rat RLE-6TN cells were assigned into a control group (21% O₂ for 4 h) and excess oxygen supply groups (95% O₂ for 1,2,3,and 4 h,res-pectively).The content of adenosine triphosphate (ATP),the activity of mitochondrial respiratory chain complex V,and the mitochondrial membrane potential were determined by luciferase assay,micro-assay,and fluorescent probe JC-1,respectively.Real-time fluorescence quantitative PCR was employed to determine the mRNA levels of NADH dehydrogenase subunit 1 (ND1),cytochrome b (Cytb),cytochrome C oxidase subunit I (COXI),and adenosine triphosphatase 6 (ATPase6) in the core subunits of mitochondrial respiratory chain complexes Ⅰ,Ⅲ,Ⅳ,and Ⅴ,respectively. Results Compared with the control group,excess oxygen supply for 1,2,3,and 4 h down-regulated the mRNA levels of ND1 (q=24.800,P<0.001;q=13.650,P<0.001;q=9.869,P<0.001;q=20.700,P<0.001),COXI (q=16.750,P<0.001;q=10.120,P<0.001;q=8.476,P<0.001;q=14.060,P<0.001),and ATPase6 (q=22.770,P<0.001;q=15.540,P<0.001;q=12.870,P<0.001;q=18.160,P<0.001).Moreover,excess oxygen supply for 1 h and 4 h decreased the ATPase activity (q=9.435,P<0.001;q=11.230,P<0.001) and ATP content (q=5.615,P=0.007;q=5.029,P=0.005).The excess oxygen supply for 2 h and 3 h did not cause significant changes in ATPase activity (q=0.156,P=0.914;q=3.197,P=0.116) and ATP content (q=0.859,P=0.557;q=1.273,P=0.652).There was no significant difference in mitochondrial membrane potential among the groups (F=0.303,P=0.869). Conclusion Short-term excess oxygen supply down-regulates the expression of the core subunits of mitochondrial respiratory chain complexes and reduces the activity of ATPase,leading to the energy metabolism disorder of alveolar epithelial type Ⅱ cells.
Animals ; Rats ; Energy Metabolism ; Adenosine Triphosphate ; Adenosine Triphosphatases ; RNA, Messenger ; Oxygen

A randomized, double-blind, placebo-controlled, multi-center phase Ⅱ clinical trial design was used in this study to recruit subjects who were in line with the syndrome of excess heat and fire toxin, and were diagnosed as recurrent oral ulcers, gingivitis, and acute pharyngitis. A total of 240 cases were included and randomly divided into a placebo group and a Huanglian Jiedu Pills group. The clinical efficacy of Huanglian Jiedu Pills in treating the syndrome of excess heat and fire toxin was evaluated by using the traditional Chinese medicine(TCM) syndrome scale. Enzyme-linked immunosorbent assay(ELISA) was used to determine and evaluate the levels of adenosine triphosphate(ATP), 4-hydroxynonenal(4-HNE), and adrenocorticotropic hormone(ACTH) in plasma of the two groups before and after administration and to predict their application value as clinical biomarkers. The results showed that the disappearance rate of main symptoms in the Huanglian Jiedu Pills group was 69.17%, and that in the placebo group was 50.83%. The comparison between the Huanglian Jiedu Pills group and the placebo group showed that 4-HNE before and after administration was statistically significant(P<0.05). The content of 4-HNE in the Huanglian Jiedu Pills group decreased significantly after administration(P<0.05), but that in the placebo group had no statistical significance and showed an upward trend. After administration, the content of ATP in both Huanglian Jiedu Pills group and placebo group decreased significantly(P<0.05), indicating that the energy metabolism disorder was significantly improved after administration of Huanglian Jiedu Pills and the body's self-healing ability also alleviated the increase in ATP level caused by the syndrome of excess heat and fire toxin to a certain extent. ACTH in both Huanglian Jiedu Pills group and placebo group decreased significantly after administration(P<0.05). It is concluded that Huanglian Jiedu Pills has a significant clinical effect, and can significantly improve the abnormal levels of ATP and 4-HNE in plasma caused by the syndrome of excess heat and fire toxin, which are speculated to be the effective clinical biomarkers for Huanglian Jiedu Pills to treat the syndrome of excess heat and fire toxin.
Humans ; Adrenocorticotropic Hormone ; Hot Temperature ; Medicine, Chinese Traditional ; Adenosine Triphosphate

OBJECTIVE: To investigate the mechanism of shikonin-induced death of human hepatocellular carcinoma SMMC-7721 cells. METHODS: Cultured SMMC-7721 cells and normal hepatocytes (L-02 cells) were treated with 4, 8, or 16 μmol/L shikonin, and the changes in cell viability was assessed using MTT assay. The levels of ATP and lactic acid in the cell cultures were detected using commercial kits. Co-immunoprecipitation and immunofluorescence staining were used to determine the relationship among pyruvate kinase M2 (PKM2), prolyl hydroxylase 3 (PHD3), and hypoxia-inducible factor-1α (HIF-1α). The expressions of PHD3, PKM2, HIF-1α, Bax, cleaved caspase-3, and Bcl-2 in SMMC-7721 cells were detected with Western blotting, and cell apoptosis was analyzed with annexin V-FITC/PI staining. The effects of RNA interference of PKM2 on PHD3 and HIF-1α expressions in SMMC-7721 cells were detected using Western blotting. RESULTS: The IC₅₀ of shikonin against SMMC-7721 and L-02 cells was 8.041 μmol/L and 31.75 μmol/L, respectively. Treatment with shikonin significantly inhibited the protein expressions of PKM2, HIF-1α and PHD3 and nuclear translocation of PKM2 and HIF-1α in SMMC-7721 cells. Coimmunoprecipitation and immunofluorescence staining confirmed that shikonin inhibited the formation of PKM2/PHD3/HIF-1α complex and significantly reduced the contents of lactic acid and ATP in SMMC-7721 cells (P < 0.05). The expressions of PHD3 and HIF-1α decreased significantly after PKM2 knockdown (P < 0.05). Shikonin treatment significantly increased the apoptosis rate, enhanced the expressions of Bax and cleaved caspase-3, and decreased Bcl-2 expression in SMMC-7721 cells (P < 0.05). CONCLUSIONS Shikonin induces apoptosis of SMMC-7721 cells possibly by inhibiting aerobic glycolysis through the PKM2/PHD3/HIF-1α signaling pathway to cause energy supply dysfunction in the cells.
Humans ; Prolyl Hydroxylases ; Carcinoma, Hepatocellular ; Caspase 3 ; bcl-2-Associated X Protein ; Liver Neoplasms ; Signal Transduction ; Apoptosis ; Adenosine Triphosphate

OBJECTIVE: To study the toxic effects of short-term exposure to gossypol on the testis and kidney in mice and whether these effects are reversible. METHODS: Twenty 7 to 8-week-old male mice were randomized into blank control group, solvent control group, gossypol treatment group and drug withdrawal group. In the former 3 groups, the mice were subjected to daily intragastric administration of 0.3 mL of purified water, 1% sodium carboxymethylcellulose solution, and 30 mg/mL gossypol solution for 14 days, respectively; In the drug withdrawal group, the mice were treated with gossypol solution in the same manner for 14 days followed by treatment with purified water for another 14 days. After the last administration, the mice were euthanized and tissue samples were collected. The testicular tissue was weighed and observed microscopically with HE and PAS staining; the kidney tissue was stained with HE and examined for mitochondrial ATPase activity. RESULTS: Compared with those in the control group, the mice with gossypol exposure showed reduced testicular seminiferous epithelial cells with rounded seminiferous tubules, enlarged space between the seminiferous tubules, interstitium atrophy of the testis, and incomplete differentiation of the spermatogonia. The gossypol-treated mice also presented with complete, non-elongated spermatids, a large number of cells in the state of round spermatids, and negativity for acrosome PAS reaction; diffuse renal mesangial cell hyperplasia, increased mesangial matrix, and adhesion of the mesangium to the wall of the renal capsule were observed, with significantly shrinkage or even absence of the lumens of the renal capsules and reduced kidney mitochondrial ATPase activity. Compared with the gossypol-treated mice, the mice in the drug withdrawal group showed obvious recovery of morphologies of the testis and the kidney, acrosome PAS reaction and mitochondrial ATPase activity. CONCLUSIONS Shortterm treatment with gossypol can cause reproductive toxicity and nephrotoxicity in mice, but these toxic effects can be reversed after drug withdrawal.
Mice ; Male ; Animals ; Gossypol/toxicity* ; Testis ; Seminiferous Tubules ; Spermatids ; Spermatogenesis ; Adenosine Triphosphatases/pharmacology*

Objective To investigate the effects of long noncoding RNA H19 on lipid accumulation of macrophages under high fat stress and its mechanism. Methods Human THP-1 cells-derived macrophages were incubated with ox-LDL, and the effects of H19 siRNA intervention on lipid accumulation was observed. The THP-1 cells were divided into control group (conventional culture), ox-LDL group, siRNA negative control (NC siRNA) combined with ox-LDL treatment group, and H19 siRNA combined with ox-LDL treatment group. Oil red O staining was used to determine the lipid accumulation in cells, and cholesterol concentration was analyzed by enzymatic method; ATP assay kit for detecting celluar ATP content; colorimetry was used to detect the levels of oxidative stress indicators and ELISA was used to detect the levels of monocyte chemoattractant protein-1 (MCP-1) in the cell supernatant. Western blot analysis was used to detect the protein expression of ATP binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor α (PPARα), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and nuclear factor κB p-p65 (NF-κB p-p65). Results Knockdown H19 significantly inhibited intracellular lipid accumulation, decreased total cholesterol (TC) and cholesterol ester (CE) content, and decreased CE/TC ratio. Knockdown H19 significantly alleviated cell damage including an increase in ATP content, a decrease in oxidative stress levels and a decrease in MCP-1 levels, which caused by high-fat stress. H19 siRNA upregulated expression of ABCA1, PPARα and PGC-1α in THP-1 derived macrophages, downregulated NF-κB signal pathway. Conclusion Knockdown H19 upregulates PGC-1α expression in THP-1 cells and downregulates NF-κB pathway, which promotes cholesterol reverse transport, reduces inflammatory reaction and inhibits lipid accumulation.
Humans ; Adenosine Triphosphate ; Cholesterol ; NF-kappa B ; PPAR alpha ; RNA, Long Noncoding/genetics* ; RNA, Small Interfering/genetics* ; THP-1 Cells ; Macrophages/metabolism* ; Lipid Metabolism

OBJECTIVES: To explore the role of mitochondrial CYB 15024G>A mutation in the development of essential hypertension. METHODS: Mitochondrial genome sequences of hypertensive patients were obtained from previous studies. Clinical and genetic data of a hypertensive patient with mitochondrial CYB 15024G>A mutation and its pedigree were analyzed. Lymphocytes derived from patient and family members were transformed into immortalized lymphoblastoid cell lines, and the levels of adenosine triphosphate (ATP), mitochondrial membrane potential and intracellular reactive oxygen species (ROS) were detected. RESULTS: The penetrance of this essential hypertension family was 42.9%, and the age of onset was 46-68 years old. Mitochondrial genome sequencing results showed that all maternal members carried a highly conserved mitochondrial CYB 15024G>A mutation. This mutation could affect the free energy of mitochondrial CYB for secondary and tertiary structure and protein folding, thereby changing its structural stability and the structure of the electron transfer function area around the mutation site. Compared with the control, the cell line carrying the mitochondrial CYB 15024G>A mutation showed significantly decreased levels of mitochondrial CYB, ATP and mitochondrial membrane potential, and increased levels of ROS (P<0.01). CONCLUSIONS Mitochondrial CYB 15024G>A mutation may affect the structure of respiratory chain subunits and mitochondrial function, leading to cell dysfunction, which suggests that the mutation may play a synergistic role in essential hypertension.
Humans ; Middle Aged ; Aged ; Reactive Oxygen Species ; Essential Hypertension/genetics* ; Adenosine Triphosphate ; Cell Line ; Mutation

Tumors in which the microenvironment is characterized by lack of immune cell infiltration are referred as "cold tumors" and typically exhibit low responsiveness to immune therapy. Targeting the factors contributing to "cold tumors" formation and converting them into "hot tumors" is a novel strategy for improving the efficacy of immunotherapy. Adenosine, a hydrolysis product of ATP, accumulates with a significantly higher concentration in the tumor microenvironments compared with normal tissue and exerts inhibitory effects on tumor-specific adaptive immunity. Tumor cells, dendritic cells, macrophages, and T cells express abundant adenosine receptors on their surfaces. The binding of adenosine to these receptors initiates downstream signaling pathways that suppress tumor antigen presentation and immune cell activation, consequently dampening adaptive immune responses against tumors. Adenosine down-regulates the expression of major histocompatibility complex Ⅱ and co-stimulatory factors on dendritic cells and macrophages, thereby inhibiting antigen presentation to T cells. Adenosine also inhibits ligand-receptor binding and transmembrane signaling on T cells, concomitantly suppressing the secretion of anti-tumor cytokines and impairing T cell activation. Furthermore, adenosine hinders effector T cell trafficking to tumor sites and infiltration by inhibiting chemokine secretion and KCa3.1 channels. Additionally, adenosine promotes the secretion of immunosuppressive cytokines, increases immune checkpoint protein expression, and enhances the activity of immunosuppressive cells, collectively curbing cytotoxic T cell-mediated tumor cell killing. Given the immunosuppressive role of adenosine in adaptive antitumor immunity, several inhibitors targeting adenosine generation or adenosine receptor blockade are currently in preclinical or clinical development with the aim of enhancing the effectiveness of immunotherapies. This review provides an overview of the inhibitory effects of adenosine on adaptive antitumor immunity, elucidate the molecular mechanisms involved, and summarizes the latest advances in application of adenosine inhibition strategies for antitumor immunotherapy.
Humans ; Adenosine/pharmacology* ; T-Lymphocytes ; Adaptive Immunity ; Cytokines ; Neoplasms/therapy* ; Tumor Microenvironment

The discovery of neuroglobin (Ngb), a brain- or neuron-specific member of the hemoglobin family, has revolutionized our understanding of brain oxygen metabolism. Currently, how Ngb plays such a role remains far from clear. Here, we report a novel mechanism by which Ngb might facilitate neuronal oxygenation upon hypoxia or anemia. We found that Ngb was present in, co-localized to, and co-migrated with mitochondria in the cell body and neurites of neurons. Hypoxia induced a sudden and prominent migration of Ngb towards the cytoplasmic membrane (CM) or cell surface in living neurons, and this was accompanied by the mitochondria. In vivo, hypotonic and anemic hypoxia induced a reversible Ngb migration toward the CM in cerebral cortical neurons in rat brains but did not alter the expression level of Ngb or its cytoplasm/mitochondria ratio. Knock-down of Ngb by RNA interference significantly diminished respiratory succinate dehydrogenase (SDH) and ATPase activity in neuronal N2a cells. Over-expression of Ngb enhanced SDH activity in N2a cells upon hypoxia. Mutation of Ngb at its oxygen-binding site (His⁶⁴) significantly increased SDH activity and reduced ATPase activity in N2a cells. Taken together, Ngb was physically and functionally linked to mitochondria. In response to an insufficient oxygen supply, Ngb migrated towards the source of oxygen to facilitate neuronal oxygenation. This novel mechanism of neuronal respiration provides new insights into the understanding and treatment of neurological diseases such as stroke and Alzheimer's disease and diseases that cause hypoxia in the brain such as anemia.
Rats ; Animals ; Neuroglobin/metabolism* ; Globins/metabolism* ; Nerve Tissue Proteins/metabolism* ; Neurons/metabolism* ; Hypoxia/metabolism* ; Brain/metabolism* ; Oxygen ; Anemia/metabolism* ; Adenosine Triphosphatases/metabolism*

The coronavirus disease 2019 (COVID-19) pandemic has stimulated tremendous efforts to develop therapeutic agents that target severe acute respiratory syndrome coronavirus 2 to control viral infection. So far, a few small-molecule antiviral drugs, including nirmatrelvir-ritonavir (Paxlovid), remdesivir, and molnupiravir have been marketed for the treatment of COVID-19. Nirmatrelvir-ritonavir has been recommended by the World Health Organization as an early treatment for outpatients with mild-to-moderate COVID-19. However, the existing treatment options have limitations, and effective treatment strategies that are cost-effective and convenient for tackling COVID-19 are still needed. To date, four domestically developed oral anti-COVID-19 drugs have been granted conditional market approval in China. These drugs include azvudine, simnotrelvir-ritonavir (Xiannuoxin), leritrelvir, and mindeudesivir (VV116). Preclinical and clinical studies have explored the efficacy and tolerability of mindeudesivir and supported its early use in mild-to-moderate COVID-19 cases at high risk for progression. In this review, we discuss the most recent findings regarding the pharmacological mechanism and therapeutic effects focusing on mindeudesivir and other small-molecule antiviral agents for COVID-19. These findings will expand our understanding and highlight the potential widespread application of China's homegrown anti-COVID-19 drugs.
Humans ; Ritonavir/therapeutic use* ; COVID-19 ; Antiviral Agents/therapeutic use* ; China ; Nitriles ; Lactams ; Proline ; Adenosine/analogs & derivatives* ; Leucine