Liraglutide does not increase heart rate of diabetic patients during acute myocardial infarction.

BACKGROUND: Glucagon-like peptide 1 receptor agonists have been shown to reduce all-cause and cardiovascular mortality in patients with Type 2 diabetes mellitus (T2DM). The probable increase in heart rate hinders its early usage in acute myocardial infarction patients. In our study, we aimed to find out whether the use of liraglutide in patients with acute myocardial infarction as early as at the time of hospitalization would increase the heart rate. METHODS: This was an observational retrospective study. From December 2020 to August 2021, 200 patients with acute myocardial infarction were included in our study and divided into three groups: T2DM + liraglutide group (n = 46), T2DM + non-liraglutide group (n = 42), and non-T2DM group (n = 112). The primary outcomes were the differences in heart rate. Secondary outcomes were differences in systolic and diastolic blood pressure. RESULTS: There were no significant differences in heart rate among the three groups at admission, the day before the first shot of liraglutide, and before discharge. There was also no significant difference in heart rate between diabetic patients with acute myocardial infarction and those on liraglutide during the hospital stay. And there were no differences of beta-blocker dosages among the three groups. Liraglutide did not affect the blood pressure during acute myocardial infarction. CONCLUSIONS: Liraglutide did not increase the heart rate in diabetic patients during acute myocardial infarction and did not lead to an increase in the dose of beta-blockers in the patients. It also had no effect on blood pressure and showed better efficacy in lowering glucose levels without additional hypoglycemic events.

TBC1D15 deficiency protects against doxorubicin cardiotoxicity via inhibiting DNA-PKcs cytosolic retention and DNA damage.

Clinical application of doxorubicin (DOX) is heavily hindered by DOX cardiotoxicity. Several theories were postulated for DOX cardiotoxicity including DNA damage and DNA damage response (DDR), although the mechanism(s) involved remains to be elucidated. This study evaluated the potential role of TBC domain family member 15 (TBC1D15) in DOX cardiotoxicity. Tamoxifen-induced cardiac-specific Tbc1d15 knockout (Tbc1d15CKO) or Tbc1d15 knockin (Tbc1d15CKI) male mice were challenged with a single dose of DOX prior to cardiac assessment 1 week or 4 weeks following DOX challenge. Adenoviruses encoding TBC1D15 or containing shRNA targeting Tbc1d15 were used for Tbc1d15 overexpression or knockdown in isolated primary mouse cardiomyocytes. Our results revealed that DOX evoked upregulation of TBC1D15 with compromised myocardial function and overt mortality, the effects of which were ameliorated and accentuated by Tbc1d15 deletion and Tbc1d15 overexpression, respectively. DOX overtly evoked apoptotic cell death, the effect of which was alleviated and exacerbated by Tbc1d15 knockout and overexpression, respectively. Meanwhile, DOX provoked mitochondrial membrane potential collapse, oxidative stress and DNA damage, the effects of which were mitigated and exacerbated by Tbc1d15 knockdown and overexpression, respectively. Further scrutiny revealed that TBC1D15 fostered cytosolic accumulation of the cardinal DDR element DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Liquid chromatography-tandem mass spectrometry and co-immunoprecipitation denoted an interaction between TBC1D15 and DNA-PKcs at the segment 594-624 of TBC1D15. Moreover, overexpression of TBC1D15 mutant (∆594-624, deletion of segment 594-624) failed to elicit accentuation of DOX-induced cytosolic retention of DNA-PKcs, DNA damage and cardiomyocyte apoptosis by TBC1D15 wild type. However, Tbc1d15 deletion ameliorated DOX-induced cardiomyocyte contractile anomalies, apoptosis, mitochondrial anomalies, DNA damage and cytosolic DNA-PKcs accumulation, which were canceled off by DNA-PKcs inhibition or ATM activation. Taken together, our findings denoted a pivotal role for TBC1D15 in DOX-induced DNA damage, mitochondrial injury, and apoptosis possibly through binding with DNA-PKcs and thus gate-keeping its cytosolic retention, a route to accentuation of cardiac contractile dysfunction in DOX-induced cardiotoxicity.

Syntaxin 17 Protects Against Heart Failure Through Recruitment of CDK1 to Promote DRP1-Dependent Mitophagy.

Mitochondrial dysfunction is suggested to be a major contributor for the progression of heart failure (HF). Here we examined the role of syntaxin 17 (STX17) in the progression of HF. Cardiac-specific Stx17 knockout manifested cardiac dysfunction and mitochondrial damage, associated with reduced levels of p(S616)-dynamin-related protein 1 (DRP1) in mitochondria-associated endoplasmic reticulum membranes and dampened mitophagy. Cardiac STX17 overexpression promoted DRP1-dependent mitophagy and attenuated transverse aortic constriction-induced contractile and mitochondrial damage. Furthermore, STX17 recruited cyclin-dependent kinase-1 through its SNARE domain onto mitochondria-associated endoplasmic reticulum membranes, to phosphorylate DRP1 at Ser616 and promote DRP1-mediated mitophagy upon transverse aortic constriction stress. These findings indicate the potential therapeutic benefit of targeting STX17 in the mitigation of HF.

Regulation of osteoclast differentiation and inflammatory signaling by TCF8 in periodontitis.

OBJECTIVES: The aim of this study was to explore the potential role of zinc-finger homeodomain transcription factor (TCF8) in osteoclastogenesis and inflammation during periodontitis. MATERIALS AND METHODS: Rats with periodontitis were induced via Porphyromonas gingivalis-lipopolysaccharide (Pg-LPS) injection. The recombinant lentivirus delivering short hairpin RNA (shRNA) against TCF8 was used to downregulate TCF8 in vivo. Alveolar bone loss in rats was determined by micro-computed tomography (Micro-CT). Typical pathological changes, periodontal tissue inflammation, and osteoclastogenesis were evaluated via histological analyses. The RAW264.7-derived osteoclasts were induced by RANKL stimulation. TCF8 downregulation in vitro was achieved by lentivirus infection. The osteoclast differentiation and inflammatory signaling in RANKL-induced cells were measured via immunofluorescence methods and molecular biology approaches. RESULTS: Porphyromonas gingivalis-lipopolysaccharide induced rats exhibited overexpressed TCF8 in their periodontal tissues, while TCF8 knockdown attenuated the bone loss, tissue inflammation, and osteoclastogenesis in LPS-induced rats. Besides, TCF8 silencing inhibited RANKL-induced osteoclast differentiation in RAW264.7 cells, as evidenced by the reduced numbers of TRAP-positive osteoclasts, less formation of F-actin rings, and downregulated expressions of osteoclast-specific markers. It also exerted an inhibitory effect on the NF-κB signaling in RANKL-induced cells via blocking NF-κB p65 phosphorylation and nuclear translocation. CONCLUSIONS: TCF8 silencing inhibited alveolar bone loss, osteoclast differentiation, and inflammation in periodontitis.

The effects of nano-silver loaded zirconium phosphate on antibacterial properties, mechanical properties and biosafety of room temperature curing PMMA materials.

Polymethyl methacrylate (PMMA) frequently features in dental restorative materials due to its favorable properties. However, its surface exhibits a propensity for bacterial colonization, and the material can fracture under masticatory pressure. This study incorporated commercially available RHA-1F-II nano-silver loaded zirconium phosphate (Ag-ZrP) into room-temperature cured PMMA at varying mass fractions. Various methods were employed to characterize Ag-ZrP. Subsequently, an examination of the effects of Ag-ZrP on the antimicrobial properties, biosafety, and mechanical properties of PMMA materials was conducted. The results indicated that the antibacterial rate against Streptococcus mutans was enhanced at Ag-ZrP additions of 0%wt, 0.5%wt, 1.0%wt, 1.5%wt, 2.0%wt, 2.5%wt, and 3.0%wt, achieving respective rates of 53.53%, 67.08%, 83.23%, 93.38%, 95.85%, and 98.00%. Similarly, the antibacterial rate against Escherichia coli registered at 31.62%, 50.14%, 64.00%, 75.09%, 86.30%, 92.98%. When Ag-ZrP was introduced at amounts ranging from 1.0% to 1.5%, PMMA materials exhibited peak mechanical properties. However, mechanical strength diminished beyond additions of 2.5%wt to 3.0%wt, relative to the 0%wt group, while PMMA demonstrated no notable cytotoxicity below a 3.0%wt dosage. Thus, it is inferred that optimal antimicrobial and mechanical properties of PMMA materials are achieved with nano-Ag-ZrP (RHA-1F-II) additions of 1.5%wt to 2.0%wt, without eliciting cytotoxicity.

TBC1D15-Drp1 interaction-mediated mitochondrial homeostasis confers cardioprotection against myocardial ischemia/reperfusion injury.

OBJECTIVE: Mitochondria are essential for myocardial ischemia/reperfusion (I/R) injury. TBC domain family member 15 (TBC1D15) participates in the regulation of mitochondrial homeostasis although its role remains elusive in I/R injury. METHODS AND MATERIALS: This study examined the role of TBC1D15 in mitochondrial homeostasis under myocardial I/R injury using inducible cardiac-specific TBC1D15 knockin (TBC1D15CKI) and knockout (TBC1D15CKO) mice. RESULTS: TBC1D15 mRNA/protein levels were downregulated in human ischemic cardiomyopathy samples, mouse I/R hearts and neonatal mouse cardiomyocytes with H/R injury, consistent with scRNA sequencing finding from patients with coronary heart disease. Cardiac-specific knockin of TBC1D15 attenuated whereas cardiac-specific knockout of TBC1D15 overtly aggravated I/R-induced cardiomyocyte apoptosis and cardiac dysfunction. TBC1D15CKI mice exhibited reduced mitochondrial damage and mitochondrial fragmentation following myocardial I/R injury, while TBC1D15CKO mice displayed opposite results. TBC1D15 preserved mitochondrial function evidenced by safeguarding MMP and oxygen consumption capacity, antagonizing ROS accumulation and cytochrome C release, which were nullified by TBC1D15 knockdown. Time-lapse confocal microscopy revealed that TBC1D15 activated asymmetrical mitochondrial fission through promoting mitochondria-lysosome contacts untethering in NMCMs under H/R injury, whereas overexpression of TBC1D15 mutants (R400K and ∆231-240) failed to regulate asymmetrical fission and knockdown of TBC1D15 slowed down asymmetrical fission. Moreover, TBC1D15-offered benefits were mitigated by knockdown of Fis1 and Drp1. Mechanistically, TBC1D15 recruited Drp1 to mitochondria-lysosome contact sites via direct interaction with Drp1 through its C terminus (574-624) domain. Interfering with interaction between TBC1D15 and Drp1 abrogated asymmetrical mitochondrial fission and mitochondrial function. Cardiac phenotypes of TBC1D15CKO mice upon I/R injury were rescued by adenovirus-mediated overexpression of wild-type but not mutants (R400K, ∆231-240 and ∆574-624) TBC1D15. CONCLUSIONS: TBC1D15 ameliorated I/R injury through a novel modality to preserve mitochondrial homeostasis where mitochondria-lysosome contacts (through the TBC1D15/Fis1/RAB7 cascade) regulate asymmetrical mitochondrial fission (TBC1D15/Drp1 interaction), suggesting promises of targeting TBC1D15 in the management of myocardial I/R injury.

Inhibitor of Growth 4 (ING4) Plays a Tumor-repressing Role in Oral Squamous Cell Carcinoma via Nuclear Factor Kappa-B (NF-kB)/DNA Methyltransferase 1 (DNMT1) Axis-mediated Regulation of Aldehyde Dehydrogenase 1A2 (ALDH1A2).

BACKGROUND: Inhibitor of growth 4 (ING4) level was reported to be decreased in head and neck squamous cell carcinoma (HNSC) tissue, however, it is unknown whether and how ING4 participates in regulating the development of oral squamous cell carcinoma (OSCC). OBJECTIVE: This study aimed to investigate the role and mechanism of ING4 in OSCC. METHODS: ING4 was forced to up- or down-regulated in two OSCC cell lines, and its effects on the malignant behavior of OSCC cells were investigated in vitro. The ubiquitination level of NF-kB p65 in ING4 upregulated cells was measured by co-immunoprecipitation. Moreover, the effects of ING4 on the methylation level of ALDH1A2 were evaluated by methylation-specific polymerase chain reaction (MSP) assay. The role of ING4 in OSCC growth in vivo was observed in nude mice. RESULTS: Our results showed that the expression of ING4 in OSCC cell lines was lower than that in normal oral keratinocyte cells. In vitro, ING4 overexpression inhibited the proliferation, migration, and invasion of OSCC cell lines and ING4 silencing exhibited opposite results. We also demonstrated that ING4 overexpression promoted the ubiquitination and degradation of P65 and reduced DNA methyltransferase 1 (DNMT1) expression and Aldehyde dehydrogenase 1A2 (ALDH1A2) methylation. Moreover, overexpression of p65 rescued the suppression of malignant behavior, induced by ING4 overexpression. In addition, ING4 negatively regulated the growth of OSCC xenograft tumors in vivo. CONCLUSION: Our data evidenced that ING4 played a tumor-repressing role in OSCC in vivo and in vitro via NF-κB/DNMT1/ALDH1A2 axis.

UBE2L3 promotes squamous cell carcinoma progression in the oral cavity and hypopharynx via activating the NF-κB signaling by increasing IκBα degradation.

Oral squamous cell carcinoma (OSCC) and hypopharyngeal squamous cell carcinoma (HSCC) are representative of head and neck squamous cell carcinoma (HNSCC) and the molecular pathogenesis has not been completely clarified. Ubiquitin-conjugating enzyme E2 L3 (UBE2L3) is the key member of the E2 family that encodes 153 amino acid residues. Previous studies demonstrate that UBE2L3 is aberrantly overexpressed in various types of human cancers, suggesting that UBE2L3 may function as an oncogene. However, its functional role and the potential mechanisms in the OSCC and HSCC remain unclear. In the present study, we found that UBE2L3 was significantly upregulated in clinical HNSCC samples and HNSCC cell lines, and patients with lower UBE2L3 expression have a higher survival rate. Two HNSCC cell lines FaDu (HSCC cells) and CAL-27 (OSCC cells) with moderate expression of UBE2L3 were selected for in vitro experiments. We proved that UBE2L3 overexpression was positively associated with cellular malignant phenotypes in vitro, including proliferation, invasion, migration, and tumor growth in vivo. Conversely, UBE2L3 suppression diametrically yielded opposing results. Our further study demonstrated that overexpression of UBE2L3 significantly activated the nuclear factor kappa B (NF-κB) signaling pathway through promoting NF-κB p65 nuclear translocation and the ubiquitination and degradation of IκBα protein. Additionally, UBE2L3 was proved to be targeted and negatively regulated by miR-378a-5p, and UBE2L3 overexpression reversed the effects of miR-378a-5p upregulation. Collectively, the present study indicates that UBE2L3 may promote OSCC and HSCC progression via activating the NF-κB signaling by increasing IκBα degradation, indicating that UBE2L3 may be a potential therapeutic target for the treatment of HNSCC.

YEATS domain-containing 2 (YEATS2), targeted by microRNA miR-378a-5p, regulates growth and metastasis in head and neck squamous cell carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide with poor prognosis and the development of HNSCC is a complex process. Some research have found that YEATS domain-containing 2 (YEATS2) is highly expressed in non-small cell lung cancer and pancreatic cancer, whereas its function in HNSCC is left to be studied. The primary aim was to investigate the role of YEATS2 in proliferation, apoptosis, invasion and migration in HNSCC cells and explore the possible mechanisms. We found YEATS2 expression was elevated in HNSCC clinical samples. Our work also indicated YEATS2 knockdown inhibited cell proliferation, induced apoptosis, and diminished the migration and invasion capability in HNSCC cell lines, including Detroit562 and FaDu cells. Besides, these inhibiting effects of YEATS2 knockdown could be crippled by microRNA-378a-5p (miR-378a-5p) inhibitor. In conclusion, our data suggested that YEATS2 expression was regulated by miR-378a-5p and YEATS2 knockdown inhibited proliferation and metastasis while induced apoptosis in HNSCC cells.

NCAPG, mediated by miR-378a-3p, regulates cell proliferation, cell cycle progression, and apoptosis of oral squamous cell carcinoma through the GSK-3ß/ß-catenin signaling.

Exploring the molecular mechanism of oral squamous cell carcinoma (OSCC) pathogenesis is of great significance for its improvement and therapy. Non-structural maintenance of chromatin condensin I complex subunit G (NCAPG) is responsible for chromatin condensation and is associated with the progression of many malignant tumors. This study was aimed to investigate the role of NCAPG on OSCC pathogenesis. NCAPG mRNA expression data in OSCC tissues were obtained from the Gene Expression Omnibus (GEO) database and NCAPG protein expression in OSCC cell lines was determined by western blotting analysis. The results demonstrated that NCAPG expression in OSCC tissues and cells was higher than that of normal control. Following the short interfering RNA (siRNA) knockdown of NCAPG in two OSCC cell lines, we observed that NCAPG depletion notably inhibited OSCC proliferation and cell cycle progression, as well as promoted apoptosis in vitro. Besides, silencing of NCAPG specifically inhibited the GSK-3ß/ß-catenin signaling. Furthermore, we demonstrated that NCAPG was a downstream target of miR-378a-3p. NCAPG silencing counteracted the effect of the miR-378a-3p inhibitor on cell proliferation/cycle induction. Collectively, these findings suggest that NCAPG is crucial in OSCC progression and development, and may serve as a potential therapeutic target for OSCC.

Deletion of the E3 ubiquitin ligase, Parkin, exacerbates chronic alcohol intake-induced cardiomyopathy through an Ambra1-dependent mechanism.

BACKGROUND AND PURPOSE: Chronic alcohol consumption contributes to contractile dysfunction and unfavourable geometric changes in myocardium, accompanied by altered autophagy and disturbed mitochondrial homeostasis. The E3 ubiquitin ligase Parkin encoded by PARK2 gene maintains a fundamental role in regulating mitophagy and mitochondrial homeostasis, although little is known of its role in the aetiology of alcoholic cardiomyopathy. Here we assessed the effects of Parkin deletion in chronic alcohol-evoked cardiotoxicity. EXPERIMENTAL APPROACH: Following alcohol (4%) or control diet intake for 8 weeks, adult male wild-type (WT) and PARK2 knockout (Parkin-/- ) mice were examined using echocardiography. Cardiomyocyte mechanical properties, morphology of myocardium, and mitochondrial damage were also evaluated. Autophagy and mitophagy levels were assessed by LC3B and GFP-LC3 puncta, and lysosome-dependent autophagic flux was scrutinized using GFP-mRFP-LC3 puncta and Bafilomycin A1 treatment. KEY RESULTS: Chronic alcohol exposure provoked unfavourable geometric changes in myocardium and led to mitochondrial dysfunction and cardiac contractile defects, effects further exacerbated by Parkin knockout. Chronic alcohol exposure provoked autophagy and PINK1/Parkin-mediated mitophagy without affecting lysosome-dependent autophagic flux, the effects of which were diminished by Parkin deletion. Parkin adenovirus infection in neonatal rat cardiomyocytes further increased autophagy and protected against alcohol-induced myocardial injury, effects blocked by siRNA for Ambra1 (Autophagy and Beclin1 regulator 1). Immunofluorescence staining and co-immunoprecipitation assays showed interactions between Parkin and Ambra1. CONCLUSIONS AND IMPLICATIONS: Parkin was essential for cardiac homeostasis in alcohol challenge, accompanied by increased autophagy/mitophagy and maintenance of mitochondrial integrity through its interaction with Ambra1.

TAX1BP1 protects against myocardial infarction-associated cardiac anomalies through inhibition of inflammasomes in a RNF34/MAVS/NLRP3-dependent manner.

Acute myocardial infarction (MI), one of the most common cardiovascular emergencies, is a leading cause of morbidity and mortality. Ample evidence has revealed an essential role for inflammasome activation and autophagy in the pathogenesis of acute MI. Tax1-binding protein 1 (TAX1BP1), an adaptor molecule involved in termination of proinflammatory signaling, serves as an important selective autophagy adaptor, but its role in cardiac ischemia remains elusive. This study examined the role of TAX1BP1 in myocardial ischemic stress and the underlying mechanisms involved. Levels of TAX1BP1 were significantly downregulated in heart tissues of patients with ischemic heart disease and in a left anterior descending (LAD) ligation-induced model of acute MI. Adenovirus carrying TAX1BP1 was delivered into the myocardium. The acute MI induced procedure elicited an infarct and cardiac dysfunction, the effect of which was mitigated by TAX1BP1 overexpression with little effect from viral vector alone. TAX1BP1 nullified acute MI-induced activation of the NLRP3 inflammasome and associated mitochondrial dysfunction. TAX1BP1 overexpression suppressed NLRP3 mitochondrial localization by inhibiting the interaction of NLRP3 with mitochondrial antiviral signaling protein (MAVS). Further investigation revealed that ring finger protein 34 (RNF34) was recruited to interact with TAX1BP1 thereby facilitating autophagic degradation of MAVS through K27-linked polyubiquitination of MAVS. Knockdown of RNF34 using siRNA nullified TAX1BP1 yielded protection against hypoxia-induced MAVS mitochondrial accumulation, NLRP3 inflammasome activation and associated loss of mitochondrial membrane potential. Taken together, our results favor a cardioprotective role for TAX1BP1 in acute MI through repression of inflammasome activation in a RNF34/MAVS-dependent manner.

Parkin overexpression alleviates cardiac aging through facilitating K63-polyubiquitination of TBK1 to facilitate mitophagy.

Cumulative clinical and experimental evidence has revealed a cardinal role for mitochondrial integrity in cardiac aging. Parkin-mediated mitophagy is essential to ensure mitochondrial quality control in myocardium. This study was designed to examine the impact of Parkin overexpression on aging-induced myocardial anomalies and the underlying mechanisms with a focus on Parkin-regulated mitophagy. Cardiac function, myocardial apoptosis, mitochondrial ultrastructure and mitophagy were examined in young (3 mo) and old (24-26 mo) wild-type (WT) and Parkin transgenic mice. Our data revealed compromised myocardial function and mitochondrial morphology along with overtly apoptosis with advanced aging, the effects of which were attenuated by Parkin overexpression. Advanced aging dampened mitophagy as evidenced by decreased levels of Parkin, LC3II, phosphorylation of p62 and TBK1 in isolated mitochondria as well as reduced mitochondria autophagosomes, the effects of which were mitigated by restoration of mitophagy via Parkin overexpression. Using the low-dose doxorubicin (DOX) in vitro model of cell senescence, we noted that Parkin-offered beneficial effect against senescence was abolished by the TBK1 kinase inhibitor BX795. With TBK1 overexpression in cardiomyocytes, we uncovered the interaction of Parkin with TBK1 using a Co-immunoprecipitation (Co-IP) assay. The interaction of Parkin with TBK1 contributed to K63-linked polyubiquitination of TBK1. Our study also noted that DOX disturbed K63-linked polyubiquitination of TBK1 with downregulation of Parkin. Parkin overexpression promoted K63-linked polyubiquitination of TBK1 through Lys30 and Lys401 residues to foster TBK1 phosphorylation to facilitate efficient mitophagy. In summary, these findings suggested that Parkin effectively rescued cardiac aging through promoting K63-linked polyubiquitination of TBK1 to facilitate mitophagy.

TBC1D15/RAB7-regulated mitochondria-lysosome interaction confers cardioprotection against acute myocardial infarction-induced cardiac injury.

Rationale: Ischemic heart disease remains a primary threat to human health, while its precise etiopathogenesis is still unclear. TBC domain family member 15 (TBC1D15) is a RAB7 GTPase-activating protein participating in the regulation of mitochondrial dynamics. This study was designed to explore the role of TBC1D15 in acute myocardial infarction (MI)-induced cardiac injury and the possible mechanism(s) involved. Methods: Mitochondria-lysosome interaction was evaluated using transmission electron microscopy and live cell time-lapse imaging. Mitophagy flux was measured by fluorescence and western blotting. Adult mice were transfected with adenoviral TBC1D15 through intra-myocardium injection prior to a 3-day MI procedure. Cardiac morphology and function were evaluated at the levels of whole-heart, cardiomyocytes, intracellular organelles and cell signaling transduction. Results: Our results revealed downregulated level of TBC1D15, reduced systolic function, overt infarct area and myocardial interstitial fibrosis, elevated cardiomyocyte apoptosis and mitochondrial damage 3 days after MI. Overexpression of TBC1D15 restored cardiac systolic function, alleviated infarct area and myocardial interstitial fibrosis, reduced cardiomyocyte apoptosis and mitochondrial damage although TBC1D15 itself did not exert any myocardial effect in the absence of MI. Further examination revealed that 3-day MI-induced accumulation of damaged mitochondria was associated with blockade of mitochondrial clearance because of enlarged defective lysosomes and subsequent interrupted mitophagy flux, which were attenuated by TBC1D15 overexpression. Mechanistic studies showed that 3-day MI provoked abnormal mitochondria-lysosome contacts, leading to lysosomal enlargement and subsequently disabled lysosomal clearance of damaged mitochondria. TBC1D15 loosened the abnormal mitochondria-lysosome contacts through both the Fis1 binding and the RAB7 GAPase-activating domain of TBC1D15, as TBC1D15-dependent beneficial responses were reversed by interference with either of these two domains both in vitro and in vivo. Conclusions: Our findings indicated a pivotal role of TBC1D15 in acute MI-induced cardiac anomalies through Fis1/RAB7 regulated mitochondria-lysosome contacts and subsequent lysosome-dependent mitophagy flux activation, which may provide a new target in the clinical treatment of acute MI.

Luteolin Attenuates Doxorubicin-Induced Cardiotoxicity Through Promoting Mitochondrial Autophagy.

Doxorubicin is a valuable antineoplastic drug although its clinical use is greatly hindered by its severe cardiotoxicity with dismal target therapy available. Luteolin is a natural product extracted from vegetables and fruits with a wide range of biological efficacies including anti-oxidative, anti-tumorigenic, and anti-inflammatory properties. This study was designed to examine the possible effect of luteolin on doxorubicin-induced cardiotoxicity, if any, and the mechanism(s) involved with a focus on mitochondrial autophagy. Luteolin application (10 µM) in adult mouse cardiomyocytes overtly improved doxorubicin-induced cardiomyocyte contractile dysfunction including elevated peak shortening amplitude and maximal velocity of shortening/relengthening along with unchanged duration of shortening and relengthening. Luteolin alleviated doxorubicin-induced cardiotoxicity including apoptosis, accumulation of reactive oxygen species (ROS) and loss of mitochondrial membrane potential. Furthermore, luteolin attenuated doxorubicin-induced cardiotoxicity through promoting mitochondrial autophagy in association with facilitating phosphorylation of Drp1 at Ser616, and upregulating TFEB expression. In addition, luteolin treatment partially attenuated low dose doxorubicin-induced elongation of mitochondria. Treatment of Mdivi-1, a Drp1 GTPase inhibitor, negated the protective effect of luteolin on levels of TFEB, LAMP1, and LC3B, as well as loss of mitochondrial membrane potential and cardiomyocyte contractile dysfunction in the face of doxorubicin challenge. Taken together, these findings provide novel insights for the therapeutic efficacy of luteolin against doxorubicin-induced cardiotoxicity possibly through improved mitochondrial autophagy.

CCN5 inhibits proliferation and promotes apoptosis of oral squamous cell carcinoma cells.

Oral squamous cell carcinoma (OSCC) is a common cancer with poor prognosis and high mortality. The role of CCN5 has attracted a great focus on the regulation of cancer progression. However, the biological function and mechanism of CCN5 in OSCC are still not well elucidated. The current study was designed to determine the effects of CCN5 on OSCC cell proliferation and apoptosis using two OSCC cell lines. Further, LY294002, a PI3K/AKT antagonist, was employed to explore the mechanism underlying the effects of CCN5 in the regulation of OSCC. The results showed that overexpression of CCN5 in TSCCa cells significantly reduced viable cell number, arrested cell cycle, and suppressed cell-cycle regulators (cyclin D1, cyclin E, and CDK2). CCN5 overexpression increased the apoptotic ratio and Hoechst-positive cell number, and altered the apoptotic-related proteins (caspase-3/9, Bax, and Bcl-2). However, CCN5 silencing induced opposite effects on cell proliferation and apoptosis in Tca-8113 cells. In addition, we observed that CCN5 knockdown increased the expression levels of PI3K (p85α and p110α) and phosphorylated AKT at serine 473 (p-AKT Ser473) in Tca-8113 cells. Inhibiting PI3K/AKT signaling with LY294002 rescued the apoptotic process in CCN5-silenced OSCC cells. Finally, xenograft analysis showed that CCN5 represses tumorigenesis of OSCC cells. These findings together suggest that CCN5 functions as a tumor suppressor for OSCC cell development through inactivation of PI3K/AKT signaling pathway, providing a potential candidate for OSCC therapy.

MicroRNA-378-3p/5p suppresses the migration and invasiveness of oral squamous carcinoma cells by inhibiting KLK4 expression.

Distant metastasis frequently occurs in oral squamous cell carcinoma (OSCC) and contributes to the adverse prognosis for patients with OSCC. However, the potential mechanisms behind the metastasis have not yet been clarified. This study investigated the role of miR-378 in the migration and invasiveness of OSCC in vitro and in vivo. According to our results, the migration and invasiveness of OSCC cells were increased in cells overexpressing miR-378, and reduced in cells where miR-378-3p/5p was silenced. In addition, overexpression of miR-378 suppressed the expressions and activities of matrix metalloproteinase 9 (MMP-9) and MMP-2. Epithelial-mesenchymal transition (EMT) was restrained by overexpression of miR-378, as evidenced by an increase in E-cadherin expression and decrease in N-cadherin and uPA expression. However, knockdown of miR-378-3p/5p produced the opposite results. Moreover, kallikrein-related peptidase 4 (KLK4) was confirmed to be a target gene of miR-378. Overexpression of KLK4 reversed the induced decrease in migration and invasiveness of cells overexpressing miR-378 by upregulating the levels of MMP-9, MMP-2, and N-cadherin, and downregulating the level of E-cadhrin. Finally, the number of metastasis nodules in the lung tissues of nude mice was reduced by overexpression of miR-378, whereas the number of metastases increased with knockdown of miR-378. Taken together, our results suggest that the miR-378-KLK4 axis is involved in the mechanisms behind the migration and invasiveness of OSCC cells. Targeting the miR-378-KLK4 axis may be an effective measure for treating OSCC.

Comparison of Effects of Different Statins on Contrast-Induced Acute Kidney Injury in Rats: Histopathological and Biochemical Findings.

Statins are a promising new strategy to prevent contrast-induced acute kidney injury (CI-AKI). In this study we compared the ameliorative effect of different statins in a rat model of CI-AKI. Sprague-Dawley rats were divided into five groups: control group; CI-AKI group; CI-AKI + rosuvastatin group (10 mg/kg/day); CI-AKI + simvastatin group (80 mg/kg/day); and CI-AKI + atorvastatin group (20 mg/kg/day). CI-AKI was induced by dehydration for 72 hours, followed by furosemide intramuscular injection 20 minutes before low-osmolar contrast media (CM) intravenous injection. Statins were administered by oral gavage once daily for 3 consecutive days before CM injection and once 4 hours after CM injection. Rats were sacrificed 24 hours after CM injection, and renal function, kidney histopathology, nitric oxide (NO) metabolites, and markers of oxidative stress, inflammation, and apoptosis were evaluated. The results showed that atorvastatin and rosuvastatin but not simvastatin ameliorated CM-induced serum creatinine elevation and histopathological alterations. Atorvastatin and rosuvastatin showed similar effectiveness against CM-induced oxidative stress, but simvastatin was less effective. Atorvastatin was most effective against NO system dysfunction and cell apoptosis, whereas rosuvastatin was most effective against inflammation. Our findings indicate that statins exhibit differential effects in preventing CI-AKI when given at equivalent lipid-lowering doses.

Use of Both Serum Cystatin C and Creatinine as Diagnostic Criteria for Contrast-Induced Acute Kidney Injury and Its Clinical Implications.

BACKGROUND: Contrast-induced acute kidney injury (CI-AKI) was traditionally defined as an increase in serum creatinine (sCr) after contrast media exposure. Recently, serum cystatin C (sCyC) has been proposed as an alternative to detect acute changes in renal function. The clinical implications of combining sCyC and sCr to diagnose CI-AKI remain unknown. METHODS AND RESULTS: One thousand seventy-one consecutive patients undergoing coronary angiography/intervention were prospectively enrolled. SCyC and sCr were assessed at baseline and 24 to 48 hours after contrast media exposure. CI-AKI determined by sCr (CI-AKIsCr) was defined as an sCr increase greater than 0.3 mg/dL or 50% from baseline. Major adverse events at 12 months were assessed. CI-AKIsCr developed in 25 patients (2.3%). Twelve-month follow-up was available for 1063 patients; major adverse events occurred in 61 patients (5.7%). By receiver operating characteristic curve analysis, an sCyC increase of greater than 15% was the optimal cutoff for CI-AKIsCr detection, which occurred in 187 patients (17.4%). To evaluate the use of both sCyC and sCr as CI-AKI diagnostic criteria, we stratified patients into 3 groups: no CI-AKI, CI-AKI detected by a single marker, and CI-AKI detected by both markers. Multivariable logistic regression revealed that the predictability of major adverse events increased in a stepwise fashion in the 3 groups (no-CI-AKI group as the reference, CI-AKI detected by a single marker: odds ratio=2.25, 95% CI: 1.24-4.10, P<0.01; CI-AKI detected by both markers: odds ratio=10.00, 95% CI: 3.13-31.91, P<0.001). CONCLUSIONS: Combining sCyC and sCr to diagnose CI-AKI would be beneficial for risk stratification and prognosis in patients after contrast media exposure.

Xuezhikang ameliorates contrast media-induced nephropathy in rats via suppression of oxidative stress, inflammatory responses and apoptosis.

BACKGROUND: The aim of this study was to assess the preventive effect of xuezhikang (XZK) to replace atorvastatin on the contrast media-induced acute kidney injury (CI-AKI). METHODS: The male Sprague-Dawley rats were divided into five groups: group 1 (sham), injected with normal saline; group 2 (XZK), treated with XZK; group 3 contrast media (CM), injected with CM; group 4 (CM + ATO), injected with CM + pretreatment with atorvastatin; group 5 (CM + XZK), injected with CM + pretreatment with XZK. Twenty-four hours after injection with normal saline or CM, the blood sample and the kidneys were collected for the measurement of biochemical parameters, oxidative stress markers, nitric oxide production, inflammatory parameters, as well as renal histopathology and apoptosis detection. RESULTS: Our results indicated that XZK restored the renal function by reducing serum blood urea nitrogen (BUN) and serum creatinine (Scr), depressing renal malondialdehyde (MDA), increasing renal NO production, decreasing TNF-ɑ and IL-6 expression, attenuating renal pathological changes and inhibiting the apoptosis of renal tubular cells. CONCLUSION: XZK's therapeutic effect is similar, or even better than atorvastatin at the same effectual dose in some parts.