General anesthetic agents induce neurotoxicity through oligodendrocytes in the developing brain.

General anesthetic agents can impact brain function through interactions with neurons and their effects on glial cells. Oligodendrocytes perform essential roles in the central nervous system, including myelin sheath formation, axonal metabolism, and neuroplasticity regulation. They are particularly vulnerable to the effects of general anesthetic agents resulting in impaired proliferation, differentiation, and apoptosis. Neurologists are increasingly interested in the effects of general anesthetic agents on oligodendrocytes. These agents not only act on the surface receptors of oligodendrocytes to elicit neuroinflammation through modulation of signaling pathways, but also disrupt metabolic processes and alter the expression of genes involved in oligodendrocyte development and function. In this review, we summarize the effects of general anesthetic agents on oligodendrocytes. We anticipate that future research will continue to explore these effects and develop strategies to decrease the incidence of adverse reactions associated with the use of general anesthetic agents.

The Association Between Mitochondrial tRNAGlu Variants and Hearing Loss: A Case-Control Study.

Purpose: This study aimed to examine the frequencies of mt-tRNAGlu variants in 180 pediatric patients with non-syndromic hearing loss (NSHL) and 100 controls. Methods: Sanger sequencing was performed to screen for mt-tRNAGlu variants. These mitochondrial DNA (mtDNA) pathogenic mutations were further assessed using phylogenetic conservation and haplogroup analyses. We also traced the origins of the family history of probands carrying potential pathogenic mtDNA mutations. Mitochondrial functions including mtDNA content, ATP and reactive oxygen species (ROS) were examined in cells derived from patients carrying the mt-tRNAGlu A14692G and CO1/tRNASer(UCN) G7444A variants and controls. Results: We identified four possible pathogenic variants: m.T14709C, m.A14683G, m.A14692G and m.A14693G, which were found in NSHL patients but not in controls. Genetic counseling suggested that one child with the m.A14692G variant had a family history of NSHL. Sequence analysis of mtDNA suggested the presence of the CO1/tRNASer(UCN) G7444A and mt-tRNAGlu A14692G variants. Molecular analysis suggested that, compared with the controls, patients with these variants exhibited much lower mtDNA copy numbers, ATP production, whereas ROS levels increased (p<0.05 for all), suggesting that the m.A14692G and m.G7444A variants led to mitochondrial dysfunction. Conclusion: mt-tRNAGlu variants are important risk factors for NSHL.

The main aim of our study was to explore the association between the mt-tRNA^Glu variants and hearing loss. We found that m.T14709C, m.A14683G, m.A14692G and m.A14693G variants were associated with hearing impairments, these variants localized at extremely conserved nucleotides of mt-tRNA^Glu and may result a failure in tRNA metabolism, furthermore, patients with mt-tRNA^Glu variants exhibited much lower levels of mtDNA copy number, ATP as compared with controls, whereas ROS increased. As a result, mt-tRNA^Glu variants may serve as biomarkers for mitochondrial deafness, and screening for tRNA^Glu variants is recommended for early detection and diagnosis of mitochondrial deafness.

Reevaluating Adiponectin's impact on obesity hypertension: a Chinese case-control study.

BACKGROUND: Obesity and hypertension are major risk factors for cardiovascular diseases that affect millions of people worldwide. Both conditions are associated with chronic low-grade inflammation, which is mediated by adipokines such as adiponectin. Adiponectin is the most abundant adipokine that has a beneficial impact on metabolic and vascular biology, while high serum concentrations are associated with some syndromes. This "adiponectin paradox" still needs to be clarified in obesity-associated hypertension. The aim of this study was to investigate how adiponectin affects blood pressure, inflammation, and metabolic function in obesity hypertension using a Chinese adult case-control study. METHODS: A case-control study that had finished recruiting 153 subjects divided as four characteristic groups. Adiponectin serum levels were tested by ELISA in these subjects among these four characteristic Chinese adult physical examination groups. Waist circumference (WC), body mass index (BMI), systolic blood pressure (SB), diastolic blood pressure (DB), and other clinical laboratory data were collected. Analyzation of correlations between the research index and differences between groups was done by SPSS. RESULTS: Serum adiponectin levels in the| normal healthy group (NH group) were significantly higher than those in the newly diagnosed untreated just-obesity group (JO group), and negatively correlated with the visceral adiposity index. With multiple linear egression analysis, it was found that, for serum adiponectin, gender, serum albumin (ALB), alanine aminotransferase (ALT) and high-density lipoprotein cholesterol (HDLC) were the significant independent correlates, and for SB, age and HDLC were the significant independent correlates, and for DB, alkaline phosphatase (ALP) was the significant independent correlate. The other variables did not reach significance in the model. CONCLUSIONS: Our study reveals that adiponectin's role in obesity-hypertension is multifaceted and is influenced by the systemic metabolic homeostasis signaling axis. In obesity-related hypertension, compensatory effects, adiponectin resistance, and reduced adiponectin clearance from impaired kidneys and liver all contribute to the "adiponectin paradox".

Neutrophil CD64 index as a good biomarker for early diagnosis of bacterial infection in pregnant women during the flu season.

Background: Pregnant women are at high risk of developing febrile illness during the flu season. Early identification of a viral or bacterial infection is crucial in the management of febrile pregnant patients. Neutrophil CD64 (nCD64) has been shown to have more important diagnostic value in sepsis than traditional inflammatory indicators. Methods: The pregnant women enrolled were divided into three groups according to disease: influenza A infection, bacterial infection and healthy controls. Peripheral blood CD64, leukocyte, C-reactive protein (CRP), procalcitonin (PCT) and human Th1/Th2-related cytokines levels were routinely measured. The correlation between and diagnostic value of the nCD64 index and other biomarkers were evaluated using Spearman's correlation test and receiver operating characteristic (ROC) curve analysis. Results: Pregnant women with bacterial infection had significantly elevated levels of leukocytes (8.4 vs. 5.95, 109/L; P = 0.004), CRP (89.70 vs. 50.05 mg/mL; P = 0.031), PCT (0.13 vs. 0.04 ng/mL; P = 0.010) and TNF-α (0.46 vs. 0.38 pg/mL; P = 0.012) and an elevated nCD64 index (12.16 vs. 0.81; P < 0.001) compared with those with influenza A infection. The area under the receiver operating characteristic (AUROC) curve of the nCD64 index to discriminate bacterial infection among pregnant women (AUROC = 0.9183, P < 0.0001) was the largest. The sensitivity and specificity of the nCD64 index at an optimal cut-off value of 3.16 were 84% and 100%, respectively, with a negative predictive value (NPV) of 94%. Conclusions: Our study demonstrates the clinical value of the nCD64 index in distinguishing between bacterial infection and influenza A in pregnant women.

Mitochondrial Diabetes Is Associated with the ND4 G11696A Mutation.

Type 2 diabetes mellitus (T2DM) is a common endocrine disorder which remains a large challenge for clinicians. Previous studies have suggested that mitochondrial dysfunction plays an active role in T2DM progression, but a detailed mechanism is still elusive. In the current study, two Han Chinese families with maternally inherited T2DM were evaluated using clinical, genetic, molecular, and biochemical analyses. The mitochondrial genomes were PCR amplified and sequenced. Phylogenetic and bioinformatic analyses were used to assess the potential pathogenicity of mitochondrial DNA (mtDNA) mutations. Interestingly, the matrilineal relatives of these pedigrees exhibited variable severity of T2DM, in particular, the age at onset of T2DM varied from 26 to 65 years, with an average of 49 years. Sequence analysis revealed the presence of ND4 G11696A mutation, which resulted in the substitution of an isoleucine for valine at amino acid (AA) position 312. Indeed, this mutation was present in homoplasmy only in the maternal lineage, not in other members of these families, as well as 200 controls. Furthermore, the m.C5601T in the tRNAAla and novel m.T5813C in the tRNACys, showing high evolutional conservation, may contribute to the phenotypic expression of ND4 G11696A mutation. In addition, biochemical analysis revealed that cells with ND4 G11696A mutation exhibited higher levels of reactive oxygen species (ROS) productions than the controls. In contrast, the levels of mitochondrial membrane potential (MMP), ATP, mtDNA copy number (mtDNA-CN), Complex I activity, and NAD+/NADH ratio significantly decreased in cell lines carrying the m.G11696A and tRNA mutations, suggesting that these mutations affected the respiratory chain function and led to mitochondrial dysfunction that was involved in T2DM. Thus, our study broadened the clinical phenotypes of m.G11696A mutation.

Colorable role of interleukin (IL)-6 in obesity hypertension: A hint from a Chinese adult case-control study.

BACKGROUND: Obesity and hypertension are major risk factors for cardiovascular diseases that affect millions of people worldwide. Both conditions are associated with chronic low-grade inflammation, which is mediated by cytokines such as interleukin-6 (IL-6). IL-6 is a multifunctional cytokine that can have pro-inflammatory or anti-inflammatory effects depending on the context. The exact role of IL-6 in obesity-associated hypertension is unclear. OBJECTIVE: To investigate how IL-6 affects blood pressure, inflammation, and metabolic function in obesity-hypertension using a Chinese adult case-control study. METHODS: A total of 153 participants were sorted into four subgroups according to their body mass index (BMI) and blood pressure (BP): normal healthy group (NH), just obesity group (JO), just-hypertension group (JH), and obesity-hypertension group (OH). Serum IL-6 concentrations were measured by Enzyme-linked Immunosorbent Assay (ELISA) and their correlations with anthropometric and laboratory parameters and their differences across the subgroups were examined. Multiple linear regression analysis was performed to identify the predictors of serum IL-6 concentrations in each group. RESULTS: Serum IL-6 concentrations were higher in NH group than in JO group and correlated positively with diastolic blood pressure in NH and JO groups, but not in JH and OH groups. Serum IL-6 concentrations also correlated with albumin in NH group, alkaline phosphatase in JO group, serum creatinine and fasting blood glucose in JH group. The influencing factors of serum IL-6 concentrations varied among the four groups, with gender, diastolic blood pressure and albumin being significant predictors in NH group, alkaline phosphatase in JO group, age and serum creatinine in JH group, and none in OH group. CONCLUSIONS: These results suggest that IL-6 may play diverse effects in the pathogenesis of obesity- hypertension, depending on the presence or absence of obesity and hypertension. Further studies are needed to elucidate the underlying mechanisms of IL-6 signaling and function in these diseases.

Mitochondrial tRNAGln 4394C>T Mutation May Contribute to the Clinical Expression of 1555A>G-Induced Deafness

The mitochondrial 1555A>G mutation plays a critical role in aminoglycoside-induced and non-syndromic hearing loss (AINSHL). Previous studies have suggested that mitochondrial secondary variants may modulate the clinical expression of m.1555A>G-induced deafness, but the molecular mechanism has remained largely undetermined. In this study, we investigated the contribution of a deafness-associated tRNAGln 4394C>T mutation to the clinical expression of the m.1555A>G mutation. Interestingly, a three-generation family with both the m.1555A>G and m.4394C>T mutations exhibited a higher penetrance of hearing loss than another family harboring only the m.1555A>G mutation. At the molecular level, the m.4394C>T mutation resides within a very conserved nucleotide of tRNAGln, which forms a new base-pairing (7T-66A) and may affect tRNA structure and function. Using trans-mitochondrial cybrid cells derived from three subjects with both the m.1555A>G and m.4394C>T mutations, three patients with only the m.1555A>G mutation and three control subjects without these primary mutations, we observed that cells with both the m.1555A>G and m.4394C>T mutations exhibited more severely impaired mitochondrial functions than those with only the m.1555A>G mutation. Furthermore, a marked decrease in mitochondrial RNA transcripts and respiratory chain enzymes was observed in cells harboring both the m.1555A>G and m.4394C>T mutations. Thus, our data suggest that the m.4394C>T mutation may play a synergistic role in the m.1555A>G mutation, enhancing mitochondrial dysfunctions and contributing to a high penetrance of hearing loss in families with both mtDNA pathogenic mutations.

Late onset of type 2 diabetes is associated with mitochondrial tRNATrp A5514G and tRNASer(AGY) C12237T mutations.

BACKGROUND: Mitochondrial dysfunctions caused by mitochondrial DNA (mtDNA) pathogenic mutations play putative roles in type 2 diabetes mellitus (T2DM) progression. But the underlying mechanism remains poorly understood. METHODS: A large Chinese family with maternally inherited diabetes and deafness (MIDD) underwent clinical, genetic, and molecular assessment. PCR and sequence analysis are carried out to detect mtDNA variants in affected family members, in addition, phylogenetic conservation analysis, haplogroup classification, and pathogenicity scoring system are performed. Moreover, the GJB2, GJB3, GJB6, and TRMU genes mutations are screened by PCR-Sanger sequencing. RESULTS: Six of 18 matrilineal subjects manifested different clinical phenotypes of diabetes. The average age at onset of diabetic patients is 52 years. Screening for the entire mitochondrial genomes suggests the co-existence of two possibly pathogenic mutations: tRNATrp A5514G and tRNASer(AGY) C12237T, which belongs to East Asia haplogroup G2a. By molecular level, m.A5514G mutation resides at acceptor stem of tRNATrp (position 3), which is critical for steady-state level of tRNATrp . Conversely, m.C12237T mutation occurs in the variable region of tRNASer(AGY) (position 31), which creates a novel base-pairing (11A-31T). Thus, the mitochondrial dysfunctions caused by tRNATrp A5514G and tRNASer(AGY) C12237T mutations, may be associated with T2DM in this pedigree. But we do not find any functional mutations in those nuclear genes. CONCLUSION: Our findings suggest that m.A5514G and m.C12337T mutations are associated with T2DM, screening for mt-tRNA mutations is useful for molecular diagnosis and prevention of mitochondrial diabetes.

Mono-2-ethylhexyl phthalate drives progression of PINK1-parkin-mediated mitophagy via increasing mitochondrial ROS to exacerbate cytotoxicity.

Phthalate ester plasticizers are used to improve the plasticity and strength of plastics. One of the most widely used and studied, di-2-ethylhexyl phthalate (DEHP), has been labeled as an endocrine disruptor. The major and toxic metabolic derivative of DEHP, mono-2-ethylhexyl phthalate (MEHP), is capable of interfering with mitochondrial function, but its mechanism of action on mitophagy remains elusive. Here, we report that MEHP exacerbates cytotoxicity by amplifying the PINK1-Parkin-mediated mitophagy pathway. First, MEHP exacerbated mitochondrial damage induced by low-dose CCCP via increased reactive oxygen species (ROS) production, decreased mitochondrial membrane potential (MMP), and enhanced fragmentation in mitochondria. Second, co-exposure to MEHP and CCCP ("MEHP-CCCP") induced robust mitophagy. Mechanistically, MEHP-CCCP stabilized PINK1, increased the level of phosphorylated ubiquitin (pSer 65-Ub), and led to Parkin mitochondrial translocation and activation. Third, MEHP-CCCP synergistically caused more cell death, while inhibition of mitophagy, either through chemical or gene silencing, reduced cell death. Finally and importantly, co-treatment with N-acetyl cysteine (NAC) completely counteracted the effects of MEHP-CCCP, suggesting that mitochondrial ROS played a vital role in this process. Our results link mitophagy and MEHP cytotoxicity, providing an insight into the potential roles of endocrine disrupting chemicals (EDCs) in human diseases such as Parkinson's disease.

Electrochemical mixed aptamer-antibody sandwich assay for mucin protein 16 detection through hybridization chain reaction amplification.

A mixed aptamer-antibody sandwich assay for the determination of mucin protein 16 (MUC16) was developed based on hybridization chain reaction (HCR) with methylene blue (MB) as an electrochemical indicator. First, MUC16 antibody was adsorbed onto the surface of the Au nanoparticle (AuNP)-modified indium tin oxide (ITO) electrode to effectively capture the target MUC16. After MUC16 was captured by the MUC16 aptamer, an antibody/MUC16/aptamer sandwich structure formed for the highly selective detection of MUC16. The 3' end of the aptamer was then subjected to HCR with the assistance of auxiliary probes to obtain DNA concatemers. Numerous MB molecules bonded with G bases in the DNA concatemers by immersing the modified ITO electrode into a stirred solution containing MB with KCl. Stepwise changes in the microscopic features of the electrode surface were studied by scanning electron microscopy (SEM). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to characterize the electrochemical behavior of the different modified electrodes. The oxidation current of MB was detected by differential pulse voltammetry (DPV). Under the optimum conditions, the proposed mixed aptamer-antibody sandwich assay showed wide dynamic range from 0.39 to 200 unit mL-1 with a low detection limit of 0.02 unit mL-1 (S/N ratio = 3). The proposed method showed good accuracy, selectivity, and acceptable reproducibility. Graphical abstract An electrochemical mixed aptamer-antibody sandwich assay based on the aptamer-induced HCR amplification strategy was fabricated for the highly sensitive detection of MUC16. The mixed aptamer-antibody sandwich assay showed acceptable performance of detection range, detection limit, reproducibility, and selectivity.

Mitochondrial tRNAAla 5601C>T variant may affect the clinical expression of the LHON­related ND4 11778G>A mutation in a family.

Certain mutations in mitochondrial DNA (mtDNA) are associated with Leber's hereditary optic neuropathy (LHON). In particular, the well­known NADH dehydrogenase 4 (ND4) m.11778G>A mutation is one of the most common LHON­associated primary mutations worldwide. However, how specific mtDNA mutations, or variants, affect LHON penetrance is not fully understood. The aim of the current study was to explore the relationship between mtDNA mutations and LHON, and to provide useful information for early detection and prevention of this disease. Following the molecular characterization of a Han Chinese family with maternally inherited LHON, four out of eight matrilineal relatives demonstrated varying degrees of both visual impairment and age of onset. Through PCR amplification of mitochondrial genomes and direct Sanger sequencing analysis, a homoplasmic mitochondrial­encoded ND4 m.11778G>A mutation, alongside a set of genetic variations belonging to human mtDNA haplogroup B5b1 were identified. Among these sequence variants, alanine transfer RNA (tRNA)Ala m.5601C>T was of particular interest. This variant occurred at position 59 in the TψC loop and altered the base pairing, which led to mitochondrial RNA (mt­RNA) metabolism failure and defects in mitochondrial protein synthesis. Bioinformatics analysis suggested that the m.5601C>T variant altered tRNAAla structure. Therefore, impaired mitochondrial functions caused by the ND4 m.11778G>A mutation may be enhanced by the mt­tRNAAla m.5601C>T variant. These findings suggested that the tRNAAla m.5601C>T variant might modulate the clinical manifestation of the LHON­associated primary mutation.

The Gut Microbiota in Women Suffering from Gestational Diabetes Mellitus with the Failure of Glycemic Control by Lifestyle Modification.

Gestational diabetes mellitus (GDM) is prevalent worldwide, leading to a high risk of significant morbidity for both the mother and offspring with complications. Increasing evidences suggest that gut microbiota plays a role in the pathogenesis of GDM. Lifestyle modification is the cornerstones of GDM treatment. However, a number of patients whose blood glucose is not controlled by lifestyle modification still require exogenous insulin to control blood glucose. No observational study is available about the relationship between the gut microbiota in GDM patients and lifestyle modifications. Thus, we investigated the differences in gut microbiota between GDM patients with successful glycemic control (GDM1) and failure of glycemic control (GDM2) by lifestyle modifications. We sequenced the V3-V4 regions of 16S ribosomal ribonucleic acid (rRNA) gene from stool samples of 52 singleton pregnant women with 24-28 weeks of gestation. Our results showed that Blautia, Eubacterium_hallii_group, and Faecalibacterium in the gut microbiota showed significant differences among the normoglycemic mother, GDM1, and GDM2 groups, respectively. The combined diagnostic performance of Blautia, Eubacterium_hallii_group, and Faecalibacterium in differentiating GDM2 from GDM was considered as the most reasonable identification indicator. Gut bacteria may participate in the pathological development of GDM2 through the peroxisome proliferator-activated receptor (PPAR) signaling pathway. These results indicated that Blautia, Eubacterium_hallii_group, and Faecalibacterium had important characteristic changes in the gut microbiota of women with GDM2.

Electrochemical determination of the activity of DNA methyltransferase based on the methyl binding domain protein and a customized modular detector.

An electrochemical method is described for the determination of the activity of the DNA methyltransferase (MTase). The assay was based on the use of a commercially available customized electromagnetic modular detector, which consisted of a magnetic switch, electrical connectors and a screen-printed electrode modified with graphene oxide. The biotinylated single-strand DNA (ss-DNA) S1 was absorbed by streptavidin-modified magnetic beads (MBs) via streptavidin-biotin interaction. The biotinylated ss-DNA S1 was hybridized with the complementary ss-DNA S2. After the symmetrical sequences 5'-CCGG-3' of the duplex DNA (ds-DNA) were methylated by M. SssI CpG methyltransferase (M. SssI MTase), the symmetrical sequences 5'-CCGG-3' in the ds-DNA were recognized by glutathione S-transferase (GST) tagged methyl CpG binding protein 2 (MeCP2). The unmethylated 5'-CCGG-3' sequences were specifically cleaved by HpaII restriction endonuclease. After magnetic separation and washing, HRP-labeled GST tag monoclonal antibody and H2O2 were used as a tracer label and enzyme substrate, respectively. Electrochemical measurement was carried out at pH 7.4 in the presence of 50 µM thionine and 0.5 mM H2O2. Stepwise changes in the microscopic features of the SPE surface upon the formation of each layer were studied by scanning electron microscopy. Cyclic voltammetry and differential pulse voltammetry were used to characterize the electrochemical behavior of the different modified electrodes. Under the optimal conditions, the activity of M. SssI MTase can be determined in the activity range of 0.5-125 unit·mL-1 with a detection limit of 0.2 unit·mL-1 (at an S/N ratio of 3). The sensitivity of the immunoassay is 0.489 µA·µM-1·cm-2. Graphical abstract Schematic presentation of the electrochemical immunosensor for the determination of the activity of M. SssI CpG methyltransferase (M. SssI MTase). It is based on an electromagnetic modular detector and the use of glutathione S-transferase tagged methyl CpG binding protein 2 (GST-MeCP2).

The Mitochondrial tRNAHis G12192A Mutation May Modulate the Clinical Expression of Deafness-Associated tRNAThr G15927A Mutation in a Chinese Pedigree.

BACKGROUND: Mutations in mitochondrial tRNA (mt-tRNA) genes have been found to be associated with both syndromic and non-syndromic hearing impairment. However, the pathophysiology underlying mt-tRNA mutations in clinical expression of hearing loss remains poorly understood. OBJECTIVE: The aim of this study was to explore the potential association between mttRNA mutations and hearing loss. METHODS AND RESULTS: We reported here the molecular features of a pedigree with maternally transmitted non-syndromic hearing loss. Among 12 matrilineal relatives, five of them suffered variable degree of hearing impairment, but none of them had any medical history of using aminoglycosides antibiotics (AmAn). Genetic screening of the complete mitochondrial genomes from the matrilineal relatives identified the coexistence of mt-tRNAHis G12192A and mt-tRNAThr G15927A mutations, together with a set of polymorphisms belonging to human mitochondrial haplogroup B5b1b. Interestingly, the G12192A mutation occurred 2-bp from the 3' end of the TψC loop of mt-tRNAHis, which was evolutionarily conserved from various species. In addition, the well-known G15927A mutation, which disrupted the highly conserved C-G base-pairing at the anticodon stem of mt-tRNAThr, may lead to the failure in mt-tRNA metabolism. Furthermore, a significant decreased in ATP production and an increased ROS generation were observed in polymononuclear leukocytes (PMNs) which were isolated from the deaf patients carrying these mt-tRNA mutations, suggested that the G12192A and G15927A mutations may cause mitochondrial dysfunction that was responsible for deafness. However, the absence of any functional mutations/variants in GJB2, GJB3, GJB6 and TRMU genes suggested that the nuclear genes may not play important roles in the clinical expression of non-syndromic hearing loss in this family. CONCLUSION: Our data indicated that mt-tRNAHis G12192A mutation may increase the penetrance and expressivity of deafness-associated m-tRNAThr G15927A mutation in this family.

Premature ovarian insufficiency may be associated with the mutations in mitochondrial tRNA genes.

Premature ovarian insufficiency (POI) is a common endocrine disorder featured by the triad constituting of amenorrhea for at least four months, to date, the molecular pathogenesis of POI is largely undetermined. Despite several investigations have reported an increase in reactive oxygen species (ROS) content in idiopathic POI, the role of mitochondrial DNA (mtDNA) mutations/variants in the progression of POI has not been widely investigated. The current study aimed to explore the association between mt-tRNA mutations/variants and POI; we first used the PCR-Sanger sequencing to detect the mutations/variants in mt-tRNA genes from 50 POI patients and 30 healthy subjects. In addition, we evaluated the mitochondrial functions by using trans-mitochondrial cybrid cells containing these potential pathogenic mt-tRNA mutations. Consequently, five mutations: tRNALeu(UUR) C3303T, tRNAMet A4435G, tRNAGln T4363C, tRNACys G5821A and tRNAThr A15951G were identified. Notably, these mutations occurred at the extremely conserved nucleotides of the corresponding mt-tRNAs and may result the failure in mt-tRNA metabolism and subsequently lead to the impairment in mitochondrial protein synthesis. Furthermore, biochemical and molecular analyses of the cybrid cells containing these mutations showed a significantly lower level of ATP production when compared with the controls, whereas the ROS levels were much higher in POI patients carrying these mt-tRNA mutations, strongly indicated that these mt-tRNA mutations may cause the mitochondrial dysfunction, and play active roles in the progression and pathogensis of POI. Together, this study shaded additional light on the molecular mechanism of POI that was manifestated by mt-tRNA mutations.

Mitochondria-targeted antioxidant therapy for an animal model of PCOS-IR.

Polycystic ovary syndrome (PCOS) is a common endocrine disorder with unknown etiology and unsatisfactory clinical treatment. Considering the ethical limitations of studies involving humans, animal models that reflect features of PCOS and insulin resistance (IR) are crucial resources in investigating this syndrome. Our previous study showed that mitochondrial dysfunction resulted from pathogenic mutations of mitochondrial DNA (mtDNA), and that oxidative stress had an active role in the phenotypic manifestation of PCOS­IR. Therefore, it was hypothesized that limiting oxidative stress and mitochondrial damage may be useful and effective for the clinical treatment of PCOS­IR. For this purpose, the present study examined the therapeutic effects of the mitochondria­targeted antioxidant MitoQ10 for PCOS­IR. Furthermore, the histopathology was used to analysis the ovarian morphological changes. The endocrine and reproductive related parameters were analyzed by ELISA approach. A PCOS­IR model was successfully established by subcutaneous injection of rats with testosterone propionate and feeding a high­fat diet. The 30 female Sprague­Dawley rats were then divided into three groups, comprising a control (n=10), animal model (PCOS­IR, n=10) and MitoQ10 treatment (n=10) group. It was found that MitoQ10 significantly improved the IR condition and reversed the endocrine and reproductive conditions of PCOS. In addition, the impaired mitochondrial functions were improved following MitoQ10 administration. Notably, western blot results suggested that this antioxidant reduced the expression levels of apoptosis­related proteins cytochrome c and B­cell lymphoma­2 (Bcl­2)­associated X protein, whereas the anti­apoptotic protein Bcl­extra large was increased following MitoQ10 treatment. Taken together, the data indicated that the MitoQ10 may have a beneficial favorable therapeutic effect on animals with PCOS­IR, most likely via the protection of mitochondrial functions and regulation of programmed cell death­related proteins.

Myricetin inhibits NLRP3 inflammasome activation via reduction of ROS-dependent ubiquitination of ASC and promotion of ROS-independent NLRP3 ubiquitination.

Myricetin is a plant-derived flavonoid that exhibits diverse pharmacological properties. The NLRP3 (NLR family, pyrin domain-containing 3 protein) inflammasome is a cytosolic multiprotein complex that plays a critical role in the innate immune response and pathogenesis of multiple inflammatory disorders. The present study found that myricetin inhibited NLRP3 inflammasome assembly via promotion of reactive oxygen species (ROS)-independent ubiquitination of NLRP3 and reduction of ROS-dependent ubiquitination of ASC (apoptosis-associated speck-like protein containing a CARD), which disrupted the interaction between ASC and NLRP3 and inhibited ASC oligomerization. This effect was further confirmed in vivo using mouse models of lipopolysaccharide (LPS)-induced sepsis and alum-induced peritonitis. These results suggest the therapeutic value of myricetin by targeting NLRP3-driven inflammatory diseases.

A comparative research on obesity hypertension by the comparisons and associations between waist circumference, body mass index with systolic and diastolic blood pressure, and the clinical laboratory data between four special Chinese adult groups.

BACKGROUND: The obesity-hypertension pathogenesis is complex. From the phenotype to molecular mechanism, there is a long way to clarify the mechanism. To explore the association between obesity and hypertension, we correlate the phenotypes such as the waist circumference (WC), body mass index (BMI), systolic blood pressure (SB), and diastolic blood pressure (DB) with the clinical laboratory data between four specific Chinese adult physical examination groups (newly diagnosed untreated just-obesity group, newly diagnosed untreated obesity-hypertension group, newly diagnosed untreated just-hypertension group, and normal healthy group), and the results may show something. OBJECTIVE: To explore the mechanisms from obesity to hypertension by analyzing the correlations and differences between WC, BMI, SB, DB, and other clinical laboratory data indices in four specific Chinese adult physical examination groups. METHODS: This cross-sectional study was conducted from September 2012 to July 2014, and 153 adult subjects, 34 women and 119 men, from 21 to 69 years, were taken from four characteristic Chinese adult physical examination groups (newly diagnosed untreated just-obesity group, newly diagnosed untreated obesity-hypertension group, newly diagnosed untreated just-hypertension group, and normal healthy group). The study was approved by the ethics committee of Hangzhou Center for Disease Control and Prevention. WC, BMI, SB, DB, and other clinical laboratory data were collected and analyzed by SPSS. RESULTS: Serum levels of albumin (ALB)，alanine aminotransferase (ALT), low density lipoprotein cholesterol (LDLC), triglyceride (TG), high density lipoprotein cholesterol (HDLC), alkaline phosphatase (ALP), uric acid (Ua), and TC/HDLC (odds ratio) were statistically significantly different between the four groups. WC statistically significantly positively correlated with BMI, ALT, Ua, and serum levels of glucose (GLU), and TC/HDLC, and negatively with ALB, HDLC, and serum levels of conjugated bilirubin (CB). BMI was statistically significantly positively related to ALT, Ua, LDLC, WC, and TC/HDLC, and negatively to ALB, HDLC, and CB. DB statistically significantly positively correlated with ALP, BMI, and WC. SB was statistically significantly positively related to LDLC, GLU, serum levels of fructosamine (FA), serum levels of the total protein (TC), BMI, and WC. CONCLUSION: The negative body effects of obesity are comprehensive. Obesity may lead to hypertension through multiple ways by different percents. GGT, serum levels of gamma glutamyltransferase; ALB, serum levels of albumin; ALT, serum levels of alanine aminotransferase; LDLC, serum levels of low density lipoprotein cholesterol; TG, serum levels of triglyceride; HDLC, serum levels of high density lipoprotein cholesterol; FA, serum levels of fructosamine; S.C.R, serum levels of creatinine; IB, serum levels of indirect bilirubin; ALP, serum levels of alkaline phosphatase; CB, serum levels of conjugated bilirubin; UREA, Urea; Ua, serum levels of uric acid; GLU, serum levels of glucose; TC, serum levels of the total cholesterol; TB, serum levels of the total bilirubin; TP, serum levels of the total protein; TC/HDLC, TC/HDLC ratio.

Mitochondrial COI/tRNASer(UCN) G7444A mutation may be associated with hearing impairment in a Han Chinese family.

Mutations in mitochondrial genome have been found to be associated with hearing loss. Of these, the mitochondrial 12S rRNA and tRNASer(UCN) are the hot spots for pathogenic mutations associated with deafness. To understand the putative role of mitochondrial DNA (mtDNA) mutations in hearing loss, we recently initiated a mutational screening for the mtDNA mutations in Hangzhou area from Zhejiang Province. In this study, we described a maternally inherited Han Chinese family with high penetrance of hearing loss, notably, the penetrances of hearing loss in this family were 80% and 40%, when the aminoglycoside was included or excluded. Three matrilineal relatives in this pedigree exhibited different levels of hearing loss with different age at onset. In addition, sequence analysis of the complete mitochondrial genome showed the presence of the well-known C1494T mutation in 12S rRNA gene and the G7444A mutation in the COI/tRNASer(UCN). The C1494T mutation had been reported to be a pathogenic mutation associated with aminoglycoside-induced and non-syndromic hearing loss. While the G7444A mutation was considered as a secondary mutation associated with deafness. However, the lack of functional variants in GJB2 and TRMU genes suggested that nuclear modified genes may not play important roles in deafness expression. Thus, the combination of G7444A and C1494T mutations in mitochondrial genome may account for the high penetrance of hearing loss in this Chinese family.