Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood. This condition compromises mucosal barrier integrity particularly in the gut and oral cavity. However, the mechanisms underlying this association remain unclear. This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions. Hypoxia upregulated methyltransferase-like protein 4 (METTL4) expression in platelets, resulting in N⁶-methyladenine modification of mitochondrial DNA (mtDNA). This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation, leading to cytosolic mtDNA accumulation. Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets. This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis. Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology. Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
DNA, Mitochondrial/metabolism* ; Mouth Mucosa/pathology* ; Hypoxia/immunology* ; Methyltransferases/metabolism* ; Blood Platelets/metabolism* ; Animals ; Periodontitis/immunology* ; Humans ; Platelet Activation ; Mice

OBJECTIVETo discuss the effect of matrine on nitric oxide (NO) and asymmetric methylarginine (ADMA) metabolism pathways in serum and tissues of mice with lipopolysaccharide (LPS) -induced intestine tissue inflammation.

METHODKunming mice were randomly divided into five groups: the normal control group, the LPS group and matrine (80, 40, 20 mg x kg(-1) x d(-1)) groups. The mice were intragastrically administered with drugs for 3 d (distilled water of the same volume for the normal control group and the LPS group). One hour after the last intragastrical administration, normal saline or LPS (1 mg x kg(-1)) were intraperitoneally injected. Twelve hours later, serum and tissues were collected to determine NO and ADMA levels and observe the pathological changes of intestinal tissues. The Western blot method was adopted to detect the protein expressions of arginine methyltransferases 1 (PRMT1) and dimethylarginine dimethylaminohydrolase 2 (DDAH2) in intestinal tissues.

RESULTCompared with the model group, matrine (80, 40, 20 mg x kg(-1) x d(-1)) groups showed lower NO content in serum and tissues, higher ADMA level in serum and increased PRMT1 expression in intestinal tissues, but without effect on DDAH2 expression.

CONCLUSIONMatrine could inhibit LPS-induced intestine tissue inflammation in mice. Its action mechanism is related to the decreased NO content in serum and tissues and increased ADMA level in serum and PRMT1 expression in intestinal tissues.

Alkaloids ; administration & dosage ; Animals ; Arginine ; analogs & derivatives ; blood ; metabolism ; Humans ; Inflammation ; Intestinal Diseases ; drug therapy ; enzymology ; immunology ; metabolism ; Intestines ; drug effects ; enzymology ; immunology ; metabolism ; Lipopolysaccharides ; adverse effects ; Male ; Mice ; Nitric Oxide ; blood ; metabolism ; Protein-Arginine N-Methyltransferases ; genetics ; metabolism ; Quinolizines ; administration & dosage

OBJECTIVETo explore the interaction of folate deficiency and aberration of DNA methyltransferase 1 (DNMT1) in the progression of cervix carcinogenesis.

METHODSAll clinical samples were collected from 80 patients with cervix squamous cell carcinoma (SCC), 105 patients with cervical intraepithelial neoplasm (CINI, n = 52; CINII/III, n = 53) and 53 patients with cervix inflammation (CI). The participants were diagnosed by histology at Shanxi Province Tumor Hospital and Second Hospital of Shanxi Medical University during the period of September 2009 to May 2010. Meanwhile, cervical cancer cell lines Caski and C33A were treated with different concentration of folate. Radioimmunoassay (RIA), Western blotting and real-time PCR were used to detect the levels of serum folate, the expression of DNMT1 protein and mRNA, respectively. The data were analyzed by Student t test, ANOVA, chi-square test and Spearman correlation using SPSS statistical package. The correlation strength between factors and cervical canceration was calculated by OR and 95%CI value. Interaction effect was evaluated by the application of additive effect model.

RESULTSThe levels of serum folate (median inter-quartile range) were (2.66 ± 1.82), (2.83 ± 2.23), (3.17 ± 1.91) and (3.21 ± 1.74) ng/ml, the levels of DNMT1 protein (x(-) ± s) were 2.28 ± 0.55, 1.84 ± 0.37, 1.33 ± 0.38 and 0.92 ± 0.29, the Ct-ratio (Ct value of DNMT1/Ct value of β-actin) of DNMT1 mRNA (x(-) ± s) were 1.26 ± 0.13, 1.27 ± 0.12, 1.27 ± 0.12 and 1.33 ± 0.11 in the group of SCC, CINII/III, CINIand CI, respectively. The results showed that the serum folate levels were descended, and the expression levels of DNMT1 protein (χ(2)(tend) = 50.80, P < 0.05) and mRNA (χ(2)(tend) = 17.63, P < 0.05) were increased steadily with the severity of the cervix lesions. Moreover, our results revealed that there was an additive interaction between folate deficiency and high-expression of DNMT1 protein related to the risk of CIN and SCC. And it showed that the relative excess risk of interaction (RERI), attributable proportion of interaction (API) and synergy index(S) was 0.27, 0.14 and 1.40 in CINI group, 0.47, 0.19, 1.46 in CINII/III group, 1.60, 0.31, 1.61 in SCC group, respectively. It was found that folate was able to reduce the proliferation of Caski and C33A cells (r values were 0.954 and 0.969, all P values < 0.05), with 11.4% and 13.6% of growth inhibition at the concentration of 10 µg/ml, 64.8% and 49.4% at 1000 µg/ml in Caski and C33A cells, respectively. The result showed there was an inverse correlation between the levels of folate and DNMT1 protein (r values were -0.859 and -0.914, all P values < 0.05), with 1.96 and 1.92 of expression levels at the concentration of 10 µg/ml, and 1.60 and 1.38 at 1000 µg/ml in Caski and C33A cells, respectively. At folate concentration of 1000 µg/ml, the expression of DNMT1 protein or mRNA was higher in Caski cell than in C33A cell (t values were -4.22 and 3.50, all P values < 0.05).

CONCLUSIONOur finding indicated that the low levels of serum folate and high-expression of DNMT1 protein or mRNA seemed to be associated with high risk of cervical cancer and cervix precancerous lesion. Sufficient folate is able to effectively inhibit the growth of cervical cancer cells in vitro, and would counteract transcriptional and posttranscriptional aberration of DNMT1. It suggested that there might be a synergistic action between folate deficiency and aberration of DNMT1 in the progression of cervix carcinogenesis.

Adult ; Carcinoma, Squamous Cell ; metabolism ; pathology ; Cell Line, Tumor ; Cell Transformation, Neoplastic ; metabolism ; pathology ; Cervical Intraepithelial Neoplasia ; metabolism ; pathology ; DNA (Cytosine-5-)-Methyltransferase 1 ; DNA (Cytosine-5-)-Methyltransferases ; metabolism ; Female ; Folic Acid ; blood ; Folic Acid Deficiency ; metabolism ; Humans ; Middle Aged ; RNA, Messenger ; genetics ; Uterine Cervical Neoplasms ; metabolism ; pathology

Child, Preschool ; Cystathionine beta-Synthase ; genetics ; Folic Acid ; blood ; metabolism ; Genetic Predisposition to Disease ; Heart Defects, Congenital ; enzymology ; genetics ; Humans ; Infant ; Infant, Newborn ; Methylenetetrahydrofolate Dehydrogenase (NADP) ; genetics ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Methyltransferases ; genetics ; Minor Histocompatibility Antigens ; Polymorphism, Genetic ; Risk Factors

OBJECTIVETo investigate the efficacy, safety and the life quality improvement of uroacitides injection in the treatment for patients with advanced malignant tumors.

METHODSA total of 160 patients with advanced stage cancers were enrolled into this multicenter, open and non-randomized phase II clinical trial, including cancers of the lung (33 cases), liver (45 cases), breast (17 cases), esophagus (11 cases), stomach (18 cases), colon (19 cases), pancreas (3 cases) and kidney (4 cases), and glioma (10 cases). Uroacitides was administrated in a dose of 300 ml daily via the superior vena cava catheter for consecutive 4-8 weeks.

RESULTSOf the 160 patients, 21 dropped out and one patient died during the trial. Efficacy could be evaluated in 138 patients and safety in 160. The total objective response rate (ORR, CR + PR)) and tumor control rate (CR + PR + MR + SD) of the 138 evaluable patients were 5.8% and 65.2%, respectively. Clinical benefit response (CBR) rate was 57.2%. Major adverse effects were grade I - II and reversible nausea/vomiting (21.9%) and pain (6.3%).

CONCLUSIONUroacitides injection is effective in the control for various kinds of advanced cancers with mild, reversible and tolerable adverse effects, and can also improve the patient's quality of life. It is worth being studied further.

Breast Neoplasms ; blood ; drug therapy ; pathology ; CA-19-9 Antigen ; blood ; Carcinoembryonic Antigen ; blood ; Carcinoma, Non-Small-Cell Lung ; blood ; drug therapy ; pathology ; Catheterization, Central Venous ; Colorectal Neoplasms ; blood ; drug therapy ; pathology ; Humans ; Liver Neoplasms ; blood ; drug therapy ; pathology ; Lung Neoplasms ; blood ; drug therapy ; pathology ; Methyltransferases ; administration & dosage ; adverse effects ; antagonists & inhibitors ; therapeutic use ; Nausea ; chemically induced ; Neoplasm Staging ; Peptides ; administration & dosage ; adverse effects ; therapeutic use ; Phenylacetates ; administration & dosage ; adverse effects ; therapeutic use ; Quality of Life ; Remission Induction ; Salvage Therapy ; Treatment Outcome ; Vomiting ; chemically induced ; alpha-Fetoproteins ; metabolism

Methylation catalyzed by methyltransferases is a major metabolic pathway for an inactivation of some catecholamines, niacinamide as well as aliphatic sulfhydryl drugs and toxic hydrogen sulfides. To investigate the effects of obstructive jaundice in an animal model, common bile duct ligation (CBDL) was performed in the rat and enzyme activities of S-adenosyl-L-methionine-dependent arylamine N-methyltransferase and thiol methyltransferase were examined in liver cell fractions and serum for a period of 42 d after CBDL. Both mitochondrial and microsomal arylamine N-methyltransferase showed significant increases in their activities between the 1st through the 7th day (P < or = 0.05 to 0.001), and between the 1st through the 28th day (P X or = 0.01 to 0.001) post-ligation, although the cytosolic arylamine N-methyltransferase activity did not show a significant change compared to the activities from the sham-operated control. The mitochondrial as well as microsomal thiol methyltransferase showed significant increases in their activities between the 1st through the 28th day (P < or = 0.05 to 0.01 and P < or = 0.01 to 0.001, respectively) post-ligation, although the cytosolic thiol methyltransferase activity did not show a significant change compared to the activities from the sham-operated control. Arylamine N-methyltransferase and thiol methyltransferase in the serum from cholestatic rats also showed significant increases in their activities between the 1st through 28th day (P < or = 0.01 to 0.001), and between the 0.5th through the 42nd day (P < or = 0.05 to 0.001) post-ligation compared to the sham-operated control, respectively. Enzyme kinetic parameters (Km and Vmax) of hepatic membrane-bound arylamine N-methyltransferase and thiol methyltransferase were analyzed with the preparation from the 7th day post-ligation, using tryptamine or 4-chlorothiophenol as substrates and S-Adenosyl-L-[methyl-3H]methionine as co-substrate. The results indicate that although the Km values were about the same as the sham-operated control, the Vmax values of both enzymes increased significantly (P < or = 0.01 and 0.001, respectively). These results suggest that the biosynthesis of arylamine N-methyltransferase and thiol methyltransferase have been induced in response to obstructive jaundice.
Animal ; Bile Ducts/surgery ; Cholestasis/*enzymology ; Ligation ; Liver/*enzymology ; Methyltransferases/blood/*metabolism ; Microsomes, Liver/enzymology ; Mitochondria, Liver/enzymology ; Rats ; Rats, Sprague-Dawley ; Time Factors