Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}

The singly Cabibbo-suppressed decay Λ_{c}^{+}→nπ^{+} is observed for the first time with a statistical significance of 7.3σ by using 3.9  fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of Λ_{c}^{+}→nπ^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of Λ_{c}^{+}→pπ^{0} from the Belle experiment, the ratio of branching fractions between Λ_{c}^{+}→nπ^{+} and Λ_{c}^{+}→pπ^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays Λ_{c}^{+}→Λπ^{+} and Λ_{c}^{+}→Σ^{0}π^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.

A microbiome study reveals the potential relationship between the bacterial diversity of a gymnastics hall and human health

Currently, investigations on the microbiota of sports centers and related facilities have been carried out in some countries, which showed that Microsporum gypseum, Trichophyton mentagrophytes and T. tonsurans are important dermatoprotofungi. In China, some research on athletes and sports equipment between the fungal community and public health has made some interesting achievements. However, the bacterial group among them has not been reported. Therefore, The aim of this study was to uncover (I) gymnastic equipment is there potential pathogenic factors and (ii) is there any difference in the biomarker of bacterial in different types of gymnastic room? The samples were collected from the gymnastics halls of one university in western China and main sports equipment, including gymnastics carpets, moving barres, hoops and balls, as well as wall bars, parallel bars and horizontal bars. The 16S rDNA of all the samples was sequenced, and the analyses were performed using FaproTax, Bug base function prediction and Line Discriminant Analysis (LDA) Effect Size. A 16S rDNA sequence analysis revealed abundant bacterial species biodiversity on gymnasts and apparatuses from two gymnastics halls at a university in western China. An analysis using the FaproTax and Bugbase functional prediction platforms showed that there were some opportunistic pathogens on the athletes and equipment from the Rhythmic Gymnastics (RG) and Artistic Gymnastics (AG) halls, such as Staphylococcus and Corynebacteiaceae. Infectious agents associated with cancer induction and development, such as Ruminococcaceae, Veillonellaceae and Moraxellaceae, as well as microbial toxin producers with a potential impact on human health, were also detected. According to a line discriminant analysis (LDA effect size), the bacterial biomarker groups of the two gymnasiums were different at the phylum-genus level: for RG, Erysipelatoclostridium, Lachnospiraceae and Bacteroidales, while for AG, Rhizobiales. Based on the results of the investigation, we suggest that more comprehensive consideration should be given to indoor microbial biodiversity and related public health problems in school gymnasiums.

Short-Range Structural Connections Are More Severely Damaged in Early-Stage MS

BACKGROUND AND PURPOSE

Long-range connections are more severely damaged and relevant for cognition in long-standing MS. However, the evolution of such coordinated network damage in patients with MS is unclear. We investigated whether short- and long-range structural connections sustained equal damage in early-stage MS.

MATERIALS AND METHODS

Sixteen patients with early-stage MS and 17 healthy controls were scanned by high-resolution, multishell diffusion imaging on 7T MR imaging and assessed cognitively. We investigated macrostructural properties in short- and long-range fibers and of microstructural metrics derived from 2 quantitative diffusion MR imaging models: DTI and neurite orientation dispersion and density imaging.

RESULTS

Patients had significant WM integrity damage-that is, higher radial diffusivity and a lower intracellular volume fraction in the focal WM lesions. Compared with the healthy controls, the patients had noticeable microstructure changes in both short- and long-range fibers, including increased radial diffusivity, mean diffusivity, and axial diffusivity. Z scores further indicated greater damage in the short-range fibers than in the long-range fibers.

CONCLUSIONS

Our findings demonstrate that more severe demyelination preceding axonal degeneration occurs in short-range connections but not in long-range connections in early-stage MS, suggesting the possibility that there are cortical lesions that are undetectable by current MR imaging.

Joint Determination of Reactor Antineutrino Spectra from ^{235}U and ^{239}Pu Fission by Daya Bay and PROSPECT

A joint determination of the reactor antineutrino spectra resulting from the fission of ^{235}U and ^{239}Pu has been carried out by the Daya Bay and PROSPECT Collaborations. This Letter reports the level of consistency of ^{235}U spectrum measurements from the two experiments and presents new results from a joint analysis of both data sets. The measurements are found to be consistent. The combined analysis reduces the degeneracy between the dominant ^{235}U and ^{239}Pu isotopes and improves the uncertainty of the ^{235}U spectral shape to about 3%. The ^{235}U and ^{239}Pu antineutrino energy spectra are unfolded from the jointly deconvolved reactor spectra using the Wiener-SVD unfolding method, providing a data-based reference for other reactor antineutrino experiments and other applications. This is the first measurement of the ^{235}U and ^{239}Pu spectra based on the combination of experiments at low- and highly enriched uranium reactors.

Measurement of the Cross Section for e^{+}e^{-}→Hadrons at Energies from 2.2324 to 3.6710 GeV

Based on electron-positron collision data collected with the BESIII detector operating at the Beijing Electron-Positron Collider II storage rings, the value of R≡σ(e^{+}e^{-}→hadrons)/σ(e^{+}e^{-}→μ^{+}μ^{-}) is measured at 14 center-of-mass energies from 2.2324 to 3.6710 GeV. The resulting uncertainties are less than 3.0% and are dominated by systematic uncertainties.

Scattering of surface waves by a vertical truncated structured cylinder

This paper describes the solution to the problem of scattering of plane incident waves on water of constant depth by a bottom mounted circular cylinder, extending partially through the depth, which has an internal structure comprised of closely spaced thin vertical barriers between which fluid is allowed to flow. The problem is solved under full depth-dependent linearized water wave theory using an effective medium equation to describe the fluid motion in cylinder and effective boundary conditions to match that flow to the fluid region outside the cylinder. The interest in this problem lies in the development of novel solution methods for fully three-dimensional water wave interaction with bathymetric plate arrays. Results computed using this theory are compared with a shallow water approximation based on the recent work of Marangos & Porter (2021 Shallow water theory for structured bathymetry. Proc. R. Soc. A477, 20210421.) and with accurate computations of an exact representation of the geometry using a discrete set of plates. Other results highlight the resonant directional lensing effects of this type of cylindrical plate array device.

[Effect factors of collateral blood supply of patients with early trimester cesarean scar pregnancy]

Objective: To investigate the characteristics and effect factors of collateral blood supply of patients with early trimester cesarean scar pregnancy(CSP). Methods: This study was a multicenter case-control study, with 219 inpatients with CSP in First People's Hospital of Zhengzhou, Zhengzhou Central Hospital, Third People's Hospital of Zhengzhou and Henan No3 Provincial People's Hospital from January 1, 2017 to June 30, 2020 who were selected to obtain their clinical data. Double-blind method was performed in digital subtraction angiography imaging analysis. The patients were divided into collateral blood supply group and non-collateral blood supply group, and the incidence of collateral blood supply of patients with early trimester CSP was calculated. Multivariate binary logistic regression analysis was performed to find the independent risk factors of collateral blood supply of patients with early trimester CSP. As well, clinical outcomes after uterine artery embolization (UAE) were compared between the two groups. Results: A total of 219 patients with early trimester CSP have average age of (32.4±5.0) years old and average pregnancy of (51.0±10.6) days. The incidence of collateral blood supply was 12.3% (27 cases), of which16 cases were on the left, 6 on the right and 5 in both sides. A total of 43 collateral vessels were found, with 1.59 vessels per patient on average. Bladder artery was the most common source of collateral blood supply, accounting for 74.4% (32/43), followed by internal pudendal artery for 18.6% (8/43). Multivariate binary logistic regression analysis showed that gestational weeks ≥8 weeks, maximum diameter of gestational sac ≥50 mm and rich blood supply of gestational sac are independent risk factors for collateral blood supply of patients with early trimester CSP, with OR (95%CI) 3.68 (1.06-12.76), 7.00 (1.52-32.19)、9.96 (3.59-27.58), respectively, all P<0.05. The success rates of UAE were 100% in both groups. The reduction in serum β-Human chorionic gonadotropin (β-HCG) level at 24 hours after UAE, vaginal bleeding during uterine curettage, hysterectomy and menstrual recovery time were not found to have significant difference between groups (all P>0.05). Conclusions: Early trimester CSP leads to a certain occurrence of collateral blood supply, which may have adverse impact on the efficacy of UAE and patient safety. Gestational weeks, the maximum diameter of gestational sac and the degree of vascularization of gestation sac have certain value in suggesting the collateral blood supply of patients with early trimester CSP, which is helpful for the complete embolization of gestational sac in the process of UAE.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.

Measurement of the Absolute Branching Fraction of D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}

Using a dataset of 6.32  fb^{-1} of e^{+}e^{-} annihilation data collected with the BESIII detector at center-of-mass energies between 4178 and 4226 MeV, we have measured the absolute branching fraction of the leptonic decay D_{s}^{+}→τ^{+}ν_{τ} via τ^{+}→e^{+}ν_{e}ν[over ¯]_{τ}, and find B_{D_{s}^{+}→τ^{+}ν_{τ}}=(5.27±0.10±0.12)×10^{-2}, where the first uncertainty is statistical and the second is systematic. The precision is improved by a factor of 2 compared to the previous best measurement. Combining with f_{D_{s}^{+}} from lattice quantum chromodynamics calculations or the |V_{cs}| from the CKMfitter group, we extract |V_{cs}|=0.978±0.009±0.012 and f_{D_{s}^{+}}=(251.1±2.4±3.0)  MeV, respectively. Combining our result with the world averages of B_{D_{s}^{+}→τ^{+}ν_{τ}} and B_{D_{s}^{+}→μ^{+}ν_{μ}}, we obtain the ratio of the branching fractions B_{D_{s}^{+}→τ^{+}ν_{τ}}/B_{D_{s}^{+}→μ^{+}ν_{μ}}=9.72±0.37, which is consistent with the standard model prediction of lepton flavor universality.

[The prevalence rate and influencing factors of cough in children under 5 years old in Yiwu city, Zhejiang Province in 2019]

Objectives: To investigate the prevalence of cough and its influencing factors in community children under 5 years old. Methods: From October to December 2019, we selected 3 102 community children under the age of 5 from 50 natural villages/residential communities in 14 towns/streets of Yiwu, Zhejiang Province, using multi-stage random sampling method. A face-to-face and on-site questionnaire survey was conducted among child caregivers to collect demographic data and information about children's cough in the last 1 month. Multiple logistic regression model was used to analyze children's cough and the influencing factors of different cough states. Results: Multivariate logistic regression model analysis results showed that compared with 0-1 year old, dispersed, caregivers with education level below high school, families with 1 child under 5 years old, Cough risk was higher in 1-2, 2-3, 3-4 years old, nurseries, caregivers with education level of high school or above, and families with more than 2 children under 5 years old. OR (95%CI) values were 1.52(1.19-1.92), 1.65(1.29-2.10), 1.86(1.36-2.54), 2.59(1.99-3.38), 1.48(1.26-1.74) and 1.35(1.13-1.62), respectively. Further analysis of the influencing factors of different states of cough, multivariate logistic regression model analysis results showed that preschool status, the number of children under 5 years old in the family and the education level of caregivers were the influencing factors of acute, prolonged and chronic cough. Age was only an influencing factor of acute and persistent cough. Conclusions: The disease burden of cough in children under 5 years old community was heavy, and the cough was related to children's age, education level of caregivers, number of children under 5 years old in the family and childcare status.

Observation of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e}

Using 2.93  fb^{-1} of e^{+}e^{-} collision data taken with the BESIII detector at a center-of-mass energy of 3.773 GeV, the observation of the D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} semileptonic decay is presented. The statistical significance of the decay D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is greater than 10σ. The branching fraction of D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is measured to be (1.09±0.13_{-0.16}^{+0.09}±0.12)×10^{-3}. Here, the first uncertainty is statistical, the second is systematic, and the third originates from the assumed branching fraction of K_{1}(1270)^{-}→K^{-}π^{+}π^{-}. The fraction of longitudinal polarization in D^{0}→K_{1}(1270)^{-}e^{+}ν_{e} is determined for the first time to be 0.50±0.19_{stat}±0.08_{syst}.

First Measurement of the Absolute Branching Fraction of Λ→pμ^{-}ν[over ¯]_{μ}

The absolute branching fraction of Λ→pμ^{-}ν[over ¯]_{μ} is reported for the first time based on an e^{+}e^{-} annihilation sample of 10×10^{9}  J/ψ events collected with the BESIII detector at sqrt[s]=3.097  GeV. The branching fraction is determined to be B(Λ→pμ^{-}ν[over ¯]_{μ})=[1.48±0.21(stat)±0.08(syst)]×10^{-4}, which is improved by about 30% in precision over the previous indirect measurements. Combining this result with the world average of B(Λ→pe^{-}ν[over ¯]_{e}), we obtain the ratio {[Γ(Λ→pμ^{-}ν[over ¯]_{μ})]/[Γ(Λ→pe^{-}ν[over ¯]_{e})]} to be 0.178±0.028, which agrees with the standard model prediction assuming lepton flavor universality. The asymmetry of the branching fractions of Λ→pμ^{-}ν[over ¯]_{μ} and Λ[over ¯]→p[over ¯]μ^{+}ν_{μ} is also determined, and no evidence for CP violation is found.

Direct Measurement of the Branching Fractions B(ψ(3686)→J/ψX) and B(ψ(3770)→J/ψX), and Observation of the State R(3760) in e^{+}e^{-}→J/ψX

We report a measurement of the observed cross sections of e^{+}e^{-}→J/ψX based on 3.21  fb^{-1} of data accumulated at energies from 3.645 to 3.891 GeV with the BESIII detector operated at the BEPCII collider. In analysis of the cross sections, we measured the decay branching fractions of B(ψ(3686)→J/ψX)=(64.4±0.6±1.6)% and B(ψ(3770)→J/ψX)=(0.5±0.2±0.1)% for the first time. The energy-dependent line shape of these cross sections cannot be well described by two Breit-Wigner (BW) amplitudes of the expected decays ψ(3686)→J/ψX and ψ(3770)→J/ψX. Instead, it can be better described with one more BW amplitude of the decay R(3760)→J/ψX. Under this assumption, we extracted the R(3760) mass M_{R(3760)}=3766.2±3.8±0.4  MeV/c^{2} , total width Γ_{R(3760)}^{tot}=22.2±5.9±1.4  MeV, and product of leptonic width and decay branching fraction Γ_{R(3760)}^{ee}B[R(3760)→J/ψX]=(79.4±85.5±11.7)  eV. The significance of the R(3760) is 5.3σ. The first uncertainties of these measured quantities are from fits to the cross sections and second systematic.

Evaluation of pterygium severity with en face anterior segment optical coherence tomography and correlations with in vivo confocal microscopy

PURPOSE

To describe en face anterior segment optical coherence tomography (EF-OCT) characteristics of pterygia and their correlation with in vivo confocal microscopy (IVCM).

PATIENTS AND METHODS

In this observational case series, we prospectively included 21 eyes of 17 subjects with pterygium. All subjects underwent detailed ophthalmic examination, anterior segment photography, an ocular surface disease index (OSDI) questionnaire, IVCM, and EF-OCT. Eyes were divided into two groups according to pterygium severity (Modified Pterygium Classification System) and OSDI score. EF-OCT images for both groups were analyzed for surface area of Fuchs Patches (FP). The IVCM activity score was based on the number of inflammatory cells, blood vessels, activated keratocytes and the appearance of the cornea/pterygium at the head of the pterygium. The correlations between EF-OCT and IVCM images were then analyzed and compared in both groups.

RESULTS

EF-OCT permits clear visualization and evaluation of FPs and the border between the pterygium and the adjacent cornea. The severe pterygium group was characterized by irregular borders and larger FPs (0.13±0.06 mm² versus 0.06±0.02 mm² respectively) (P=0.003). The mean IVCM activity score was 2.36±0.81 in the severe pterygium group and 1.2±0.42 in the mild pterygium group (P=0.0013). There was a positive correlation between FP surface area and IVCM activity score. A larger FP surface area was associated with a higher activity score on IVCM.

CONCLUSION

EF-OCT allows good evaluation of pterygium extension, borders and FP surface area. EF-OCT analysis of pterygium could represent a simple, non-invasive and reproducible method to evaluate pterygium severity and activity.

O-206 Meiotic segregation analysis for reciprocal translocation carriers: Assessment of factors influencing meiotic segregation patterns

Study question

To analyze factors that could influence meiotic segregation patterns for reciprocal translocation carriers.

Summary answer

Involvement of an Acr-ch, female gender, and lower TAR1 (ratio of translocated segment 1 over the chromosome arm) were independent risk factors for alternate segregation.

What is known already

Reciprocal translocation is one of the more common structural rearrangements of chromosomes, which is associated with reproductive risks, such as infertility, spontaneous abortion and the delivery of babies with mental retardation or developmental delay. Extensive studies on meiotic segregation patterns of sperm, blastomere, and blastocysts have identified several factors that may influence the generation of unbalanced rearrangement of reciprocal translocations, including carrier’s gender and age, location of breakpoints, chromosome type, and the quadrivalent structure. However, some results are controversial.

Study design, size, duration

A retrospective study from October 2013 to December 2019, a total of 10846 blastocysts originating from 2871 oocyte retrieval cycles from 2253 couples with one of the partners carrying reciprocal were investigated. The mean maternal age was 29.97±4 years (20 –47years).

Participants/materials, setting, methods

Trophectoderm biopsy of blastocysts was performed on the 5th or 6th day of development. Whole genome amplification (WGA) was performed on all samples, and the WGA was analyzed with SNP array or NGS. Segregation patterns of quadrivalent in 10846 blastocysts were analyzed. Risk factors for segregation patterns were explored through analyzing carriers’ demographic and cytogenetic characteristics using multivariate generalized linear mixed models (GLMMs).

Main results and the role of chance

The percentage of normal/balanced blastocysts was 34.3%, and 2:2 segregation was observed in 90.0% of blastocysts. Increased TAR1 (the ratio of translocated segment 1 over the chromosome arm) was noted as an independent protective factor for the proportion of alternate segregation (P = 0.004). The female gender and involvement of an Acr-ch were found independent risk factors for alternate segregation (P &lt; 0.001). A higher TAR1 reduced the risk of adjacent-1 segregation; longer translocated segment and female gender increased the risk of adjacent-2 segregation (P = 0.009 and P &lt; 0.001, respectively). Female gender and involvement of an Acr-ch enhanced the risk of 3:1 segregation (P &lt; 0.001 and P = 0.012, respectively).

Limitations, reasons for caution

About 1400 blastocysts were not diagnosed in the 2871 cycles, which might cause bias in the results. Secondly, the interchromosomal effect of reciprocal translocations was not analyzed in this study.

Wider implications of the findings

In conclusion, a carrier’s gender, involvement of an Acr-ch, and location of breakpoints may influence the segregation patterns. Besides, involvement of an Acr-ch, female gender, and lower TAR1 are independent risk factors for alternate segregation. These results may provide more appropriate genetic counseling for couples with balanced translocation.

Trial registration number

no

P–554 Reproductive risks and preimplantation genetic testing intervention for X-autosome translocation carriers

Study question

For X-autosome translocation [t(X-A)] carriers, is it a more applicable preimplantation genetic testing (PGT) strategy, that distinguishing noncarrier from euploid/ balanced embryos and prioritized transfer?

Summary answer

Noncarrier and carrier embryos discrimination in PGT is an applicable strategy to avoid transferring genetic and reproductive risks to the offspring of t(X-A) carriers.

What is known already

Balanced t(X-A) is a specific reciprocal translocation, with a higher risk of detrimental phenotype and fertility issues compared to individuals with autosomal translocation. Alternative X-chromosome inactivation (XCI) is a specific pathogenic mechanism in this population. For carrier offspring of couples with t(X-A), the genetic counseling is challenged in both the prenatal and postpartum stages, because of the complexity and severity of phenotype outcomes that are unpredictable and associated with the complex XCI mechanism. Therefore, caution is necessary when designing a PGT strategy for couples with t(X-A).

Study design, size, duration

A retrospective study. We collected a 3-year-old girl with maternal translocation 46,X,t(X;1)(q28;p31.1) presenting with multiple congenital disabilities. Three couples with female t(X-A) carrier requesting for PGT.

Participants/materials, setting, methods

Karyotype analysis, whole-exome sequencing (WES), and X inactivation analysis were performed for the girl with congenital cardiac anomaly, language defect, and mild neurodevelopmental delay. PGT based on next-generation sequencing following the microdissecting junction region to distinguish noncarrier and carrier embryos were used in three couples with female t(X-A) carrier (Cases 1–3).

Main results and the role of chance

The girl carried a maternal balanced translocation 46,X,t(X;1)(q28;p31.1). WES revealed none monogenic mutation related to her phenotype, but she carried a rare skewed inactivation of the translocation X chromosome and spread to the adjacent interstitial 1p segment, contrary to her mother. All translocation breakpoints of Cases 1–3 were successfully identified and each couple underwent one PGT cycle. Thirty oocytes were retrieved, and 13 blastocysts were eligible for biopsy, of which 6 (46.15%) embryos were balanced and only 4 were noncarriers. Three frozen embryo transfers with noncarrier embryos resulted in the birth of two healthy children (one girl and one boy), who were subsequently confirmed to have normal karyotypes. We reported a girl with multiple congenital disabilities resulting from maternally balanced t(X-A) and validated that noncarrier and carrier embryo discrimination is an effective and applicable strategy for avoiding transferring genetic and reproductive risks to the offspring from t(X-A) carriers.

Limitations, reasons for caution

Here, we reported a girl with multiple congenital disabilities resulting from maternally balanced t(X-A) found different XCI patterns, while we did not further determine the mechanism causing the different XCI patterns between the girl and her mother.

Wider implications of the findings: We demonstrated passing on a balanced t(X-A) may result in clinical manifestations associated with the X-inactivation, and verified the PGT strategy, that distinguishing normal and carrier embryos in can widely applied in t(X-A) carrier couples to avoid the genetic and reproductive risk of transferring t(X-A) to the next generation.

Trial registration number

the National Key Research & Developmental Program of China (2018YFC1004900), the National Natural Science Foundation of China (81771645 and 81971447), the Key Grant of Prevention and Treatment of Birth Defect from Hunan Province (2019SK1012), Hunan Provincial Grant for Innovative Province Construction (2019SK4012) and the Research Grant of CITIC-Xiangya (YNXM–201916).

[Inhibition of mitochondrial reactive oxygen species reduces high glucose-induced pyroptosis and ferroptosis in H9C2 cardiac myocytes]

OBJECTIVE

To observe the effect of inhibiting mitochondrial oxidative stress and NLRP3 inflammasomes on high glucose (HG)-induced pyroptosis and ferroptosis in H9C2 cardiac muscle cells and explore the possible interactions between mitochondrial reactive oxygen species (ROS) and inflammasomes.

METHODS

H9C2 cells exposed to high glucose (35 mmol/L) were treated with the mitochondrial antioxidant mitoquinone (MitoQ), the NLRP3 antagonist MCC950, or both MCC950 and rotenone (a mitochondrial electron transport antagonist), and the cell viability was measured with CCK-8 assay. The cellular and mitochondrial ROS levels were measured using CellRox and Mitosox fluorescent probes, respectively. The cellular NLRP3 inflammasome level was detected with immunofluorescence assay, and the expressions of the key proteins related with pyroptosis and ferroptosis were determined with Western blotting.

RESULTS

HG exposure significantly lowered the viability of H9C2 cells (P < 0.01), reduced the expression of GPX4 protein (a key protein related with ferroptosis) (P < 0.01), and increased the fluorescence intensities of NLRP3 (P < 0.01) and ROS (at both the cellular and mitochondrial levels, P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.01). Treatment with either MitoQ or MCC950 significantly increased the viability of HG-exposed cells (P < 0.01), increased GPX4 expression (P < 0.01), and reduced the fluorescence intensities of NLRP3 (P < 0.01) and cellular and mitochondrial ROS (P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.05). Compared with MCC950 treatment, treatment with both MCC950 and rotenone significantly reduced the viability of HG-exposed cells (P < 0.01), lowered GPX4 expression (P < 0.01), and increased the fluorescence intensities of ROS and NLRP3 (P < 0.01) and the protein levels of NLRP3 and GSDMD-NT (P < 0.05).

CONCLUSION

MitoQ inhibits mitochondrial ROS production to reduce HGinduced NLRP3 inflammasome activation and thus suppress pyroptosis and ferroptosis of cardiac muscle cells. There may be an interaction between mitochondrial ROS and NLRP3 inflammasomes.