Electrocatalytic water-to-oxygenates conversion: redox-mediated versus direct oxygen transfer.

Electrocatalytic oxygenation of hydrocarbons with high selectivity has attracted much attention for its advantages in the sustainable and controllable production of oxygenated compounds with reduced greenhouse gas emissions. Especially when utilizing water as an oxygen source, by constructing a water-to-oxygenates conversion system at the anode, the environment and/or energy costs of producing oxygenated compounds and hydrogen energy can be significantly reduced. There is a broad consensus that the generation and transformation of oxygen species are among the decisive factors determining the overall efficiency of oxygenation reactions. Thus, it is necessary to elucidate the oxygen transfer process to suggest more efficient strategies for electrocatalytic oxygenation. Herein, we introduce oxygen transfer routes through redox-mediated pathways or direct oxygen transfer methods. Especially for the scarcely investigated direct oxygen transfer at the anode, we aim to detail the strategies of catalyst design targeting the efficient oxygen transfer process including activation of organic substrate, generation/adsorption of oxygen species, and transformation of oxygen species for oxygenated compounds. Based on these examples, the significance of balancing the generation and transformation of oxygen species, tuning the states of organic substrates and intermediates, and accelerating electron transfer for organic activation for direct oxygen transfer has been elucidated. Moreover, greener organic synthesis routes through heteroatom transfer and molecular fragment transfer are anticipated beyond oxygen transfer.

CircPIAS1 promotes hepatocellular carcinoma progression by inhibiting ferroptosis via the miR-455-3p/NUPR1/FTH1 axis.

BACKGROUND: The role of circRNAs in hepatocellular carcinoma (HCC) progression remains unclear. CircPIAS1 (circBase ID: hsa_circ_0007088) was identified as overexpressed in HCC cases through bioinformatics analysis. This study aimed to investigate the oncogenic properties and mechanisms of circPIAS1 in HCC development. METHODS: Functional analyses were conducted to assess circPIAS1's impact on HCC cell proliferation, migration, and ferroptosis. Xenograft mouse models were employed to evaluate circPIAS1's effects on tumor growth and pulmonary metastasis in vivo. Bioinformatics analysis, RNA immunoprecipitation, and luciferase reporter assays were utilized to elucidate the molecular pathways influenced by circPIAS1. Additional techniques, including RNA pulldown, fluorescence in situ hybridization (FISH), chromatin immunoprecipitation (ChIP), qPCR, and western blotting, were used to further explore the underlying mechanisms. RESULTS: CircPIAS1 expression was elevated in HCC tissues and cells. Silencing circPIAS1 suppressed HCC cell proliferation and migration both in vitro and in vivo. Mechanically, circPIAS1 overexpression inhibited ferroptosis by competitively binding to miR-455-3p, leading to upregulation of Nuclear Protein 1 (NUPR1). Furthermore, NUPR1 promoted FTH1 transcription, enhancing iron storage in HCC cells and conferring resistance to ferroptosis. Treatment with ZZW-115, an NUPR1 inhibitor, reversed the tumor-promoting effects of circPIAS1 and sensitized HCC cells to lenvatinib. CONCLUSION: This study highlights the critical role of circPIAS1 in HCC progression through modulation of ferroptosis. Targeting the circPIAS1/miR-455-3p/NUPR1/FTH1 regulatory axis may represent a promising therapeutic strategy for HCC.

Structural biology of flavivirus NS1 protein and its antibody complexes.

The genus of flavivirus includes many mosquito-borne human pathogens, such as Zika (ZIKV) and the four serotypes of dengue (DENV1-4) viruses, that affect billions of people as evidenced by epidemics and endemicity in many countries and regions in the world. Among the 10 viral proteins encoded by the viral genome, the nonstructural protein 1 (NS1) is the only secreted protein and has been used as a diagnostic biomarker. NS1 has also been an attractive target for its biotherapeutic potential as a vaccine antigen. This review focuses on the recent advances in the structural landscape of the secreted NS1 (sNS1) and its complex with monoclonal antibodies (mAbs). NS1 forms an obligatory dimer, and upon secretion, it has been reported to be hexametric (trimeric dimers) that could dissociate and bind to the epithelial cell membrane. However, high-resolution structural information has been missing about the high-order oligomeric states of sNS1. Several cryoEM studies have since shown that DENV and ZIKV recombinant sNS1 (rsNS1) are in dynamic equilibrium of dimer-tetramer-hexamer states, with tetramer being the predominant form. It was recently revealed that infection-derived sNS1 (isNS1) forms a complex of the NS1 dimer partially embedded in a High-Density Lipoprotein (HDL) particle. Structures of NS1 in complexes with mAbs have also been reported which shed light on their protective roles during infection. The biological significance of the diversity of NS1 oligomeric states remains to be further studied, to inform future research on flaviviral pathogenesis and the development of therapeutics and vaccines. Given the polymorphism of flavivirus NS1 across sample types with variations in antigenicity, we propose a nomenclature to accurately define NS1 based on the localization and origin.

Secreted dengue virus NS1 from infection is predominantly dimeric and in complex with high-density lipoprotein.

Severe dengue infections are characterized by endothelial dysfunction shown to be associated with the secreted nonstructural protein 1 (sNS1), making it an attractive vaccine antigen and biotherapeutic target. To uncover the biologically relevant structure of sNS1, we obtained infection-derived sNS1 (isNS1) from dengue virus (DENV)-infected Vero cells through immunoaffinity purification instead of recombinant sNS1 (rsNS1) overexpressed in insect or mammalian cell lines. We found that isNS1 appeared as an approximately 250 kDa complex of NS1 and ApoA1 and further determined the cryoEM structures of isNS1 and its complex with a monoclonal antibody/Fab. Indeed, we found that the major species of isNS1 is a complex of the NS1 dimer partially embedded in a high-density lipoprotein (HDL) particle. Crosslinking mass spectrometry studies confirmed that the isNS1 interacts with the major HDL component ApoA1 through interactions that map to the NS1 wing and hydrophobic domains. Furthermore, our studies demonstrated that the sNS1 in sera from DENV-infected mice and a human patient form a similar complex as isNS1. Our results report the molecular architecture of a biological form of sNS1, which may have implications for the molecular pathogenesis of dengue.

Med1 inhibits ferroptosis and alleviates liver injury in acute liver failure via Nrf2 activation.

BACKGROUND: Extensive hepatocyte mortality and the absence of specific medical therapy significantly contribute to the unfavorable prognosis of acute liver failure (ALF). Ferroptosis is a crucial form of cell death involved in ALF. In this study, we aimed to determine the impact of Mediator complex subunit 1 (Med1) on ferroptosis and its potential hepatoprotective effects in ALF. RESULTS: Med1 expression is diminished in the liver of lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced ALF mice, as well as in hepatocytes damaged by H2O2 or TNF-α/D-GalN in vitro. Med1 overexpression mitigates liver injury and decreases the mortality rate of ALF mice by ferroptosis inhibition. The mechanism by which Med1 inhibits erastin-induced ferroptosis in hepatocytes involves the upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes heme oxygenase-1 (HO-1), glutamate cysteine ligase catalytic (GCLC), and NAD(P)H quinone oxidoreductase 1 (NQO1). Furthermore, Med1 overexpression suppresses the transcription of proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver of mice with LPS/D-GalN-induced ALF. CONCLUSION: Overall, our research findings indicate that Med1 suppresses ferroptosis and alleviates liver injury in LPS/D-GalN-induced ALF through the activation of Nrf2. These findings substantiate the therapeutic viability of targeting the Med1-Nrf2 axis as a means of treating individuals afflicted with ALF.

Development of oral health resources and a mobile app for caregivers and autistic children through consensus building.

LAY ABSTRACT: Caregivers of autistic children often lack knowledge regarding oral homecare and when and where to see the dentist. To address this need, we developed a series of information on oral health. An autistic child assisted in developing two social stories to showcase a dental visit. A mobile app was developed to deliver the above mentioned. Other features include creation of customised social stories and visual schedule and an inbox to allow dentists to send messages to parents. The developed information and social stories were reviewed by experts and parents. The app also underwent anonymous and independent testing by parents. Overall the information and app were well received by the experts and parents.

Integrative multiomics profiling of passion fruit reveals the genetic basis for fruit color and aroma.

Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation, and comparison of PPF (P. edulis Sims) and YPF (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina, and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes. Comparative analysis revealed 7.6∼8.1 million single nucleotide polymorphisms, 1 million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma, and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways, and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoid metabolites accumulated more in PPF. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases. Our findings revealed that certain TPS homologs in both YPF and PPF varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the 2 passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits.

Mesenchymal stem cell-regulated miRNA-mRNA landscape in acute-on-chronic liver failure.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is a major challenge in the field of hepatology. While mesenchymal stem cell (MSC) therapy can improve the prognosis of patients with ACLF, the molecular mechanisms through which MSCs attenuate ACLF remain poorly understood. We performed global miRNA and mRNA expression profiling via next-generation sequencing of liver tissues from MSC-treated ACLF mice to identify important signaling pathways and major factors implicated in ACLF alleviation by MSCs. METHODS: Carbon tetrachloride-induced ACLF mice were treated with saline or mouse bone marrow-derived MSCs. Mouse livers were subjected to miRNA and mRNA sequencing. Related signal transduction pathways were obtained through Gene Set Enrichment Analysis. Functional enrichment, protein-protein interaction, and immune infiltration analyses were performed for the differentially expressed miRNA target genes (DETs). Hub miRNA and mRNA associated with liver injury were analyzed using LASSO regression. The expression levels of hub genes were subjected to Pearson's correlation analysis and verified using RT-qPCR. The biological functions of hub genes were verified in vitro. RESULTS: The tricarboxylic acid cycle and peroxisome proliferator-activated receptor pathways were activated in the MSC-treated groups. The proportions of liver-infiltrating NK resting cells, M2 macrophages, follicular helper T cells, and other immune cells were altered after MSC treatment. The expression levels of six miRNAs and 10 transcripts correlated with the degree of liver injury. miR-27a-5p was downregulated in the mouse liver after MSC treatment, while its target gene E2f2 was upregulated. miR-27a-5p inhibited E2F2 expression, suppressed G1/S phase transition and proliferation of hepatocytes, in addition to promoting their apoptosis. CONCLUSIONS: This is the first comprehensive analysis of miRNA and mRNA expression in the liver tissue of ACLF mice after MSC treatment. The results revealed global changes in hepatic pathways and immune subpopulations. The miR-27a-5p/E2F2 axis emerged as a central regulator of the MSC-induced attenuation of ACLF. The current findings improve our understanding of the molecular mechanisms through which MSCs alleviate ACLF.

Telomere-to-telomere assembly of cassava genome reveals the evolution of cassava and divergence of allelic expression.

Cassava is a crucial crop that makes a significant contribution to ensuring human food security. However, high-quality telomere-to-telomere cassava genomes have not been available up to now, which has restricted the progress of haploid molecular breeding for cassava. In this study, we constructed two nearly complete haploid resolved genomes and an integrated, telomere-to-telomere gap-free reference genome of an excellent cassava variety, 'Xinxuan 048', thereby providing a new high-quality genomic resource. Furthermore, the evolutionary history of several species within the Euphorbiaceae family was revealed. Through comparative analysis of haploid genomes, it was found that two haploid genomes had extensive differences in linear structure, transcriptome features, and epigenetic characteristics. Genes located within the highly divergent regions and differentially expressed alleles are enriched in the functions of auxin response and the starch synthesis pathway. The high heterozygosity of cassava 'Xinxuan 048' leads to rapid trait segregation in the first selfed generation. This study provides a theoretical basis and genomic resource for molecular breeding of cassava haploids.

Mesenchymal Stem Cells Promote Polarization of M2 Macrophages in Mice with Acute-On-Chronic Liver Failure via Mertk/JAK1/STAT6 Signaling.

Acute-on-chronic liver failure (ACLF) is a severe disease with a high mortality. Macrophage-related inflammation plays a crucial role in ACLF development. Mesenchymal stem cells (MSCs) treatment was demonstrated to be beneficial in ACLF in our previous study; however, the underlying mechanisms remain unknown. Therefore, mouse bone marrow-derived MSCs were used to treat an ACLF mouse model or cocultured with RAW264.7/J774A.1 macrophages that were stimulated with LPS. Histological and serological parameters and survival were analyzed to evaluate efficacy. We detected changes of Mer tyrosine kinase (Mertk), JAK1/STAT6, inflammatory cytokines, and markers of macrophage polarization in vitro and in vivo. In ACLF mice, MSCs improved liver function and 48-h survival of ACLF mice and alleviated inflammatory injury by promoting M2 macrophage polarization and elevated Mertk expression levels in macrophages. This is significant, as Mertk regulates M2 macrophage polarization via the JAK1/STAT6 signaling pathway.

Preclinical pharmacokinetics-related pharmacological effects of orally administered polysaccharides from traditional Chinese medicines: A review.

Polysaccharides (TCMPs) derived from traditional Chinese medicines (TCMs), such as Ganoderma lucidum, Astragalus membranaceus, Lycium barbarum, and Panax ginseng, are considered to be the main active constituents in TCMs. However, the significant pharmacological effects of orally administered TCMPs do not align well with their poor pharmacokinetics. This article aims to review the literature published mainly from 2010 to 2022, focusing on the relationship between pharmacokinetics and pharmacological effects. It has been found that unabsorbed TCMPs can exert local pharmacological effects in the gut, including anti-inflammation, anti-oxidation, regulation of intestinal flora, modulation of intestinal immunity, and maintenance of intestinal barrier integrity. Unabsorbed TCMPs can also produce systemic pharmacological effects, such as anti-tumor activity and immune system modulation, by regulating intestinal flora and immunity. Conversely, some TCMPs can be absorbed and distributed to various tissues, especially the liver, where they exhibit tissue-protecting effects against inflammation and oxidative stress-induced damage and improve glucose and lipid metabolism. In future studies, it is important to improve quality control and experimental design. Furthermore, research on enhancing the oral bioavailability of TCMPs, exploring the activity of TCMP metabolites, investigating pharmacokinetic interactions between TCMPs and oral drugs, and developing oral drug delivery systems using TCMPs holds great significance.

A systems-level mass spectrometry-based technique for accurate and sensitive quantification of the RNA cap epitranscriptome.

Chemical modifications of transcripts with a 5' cap occur in all organisms and function in many aspects of RNA metabolism. To facilitate analysis of RNA caps, we developed a systems-level mass spectrometry-based technique, CapQuant, for accurate and sensitive quantification of the cap epitranscriptome. The protocol includes the addition of stable isotope-labeled cap nucleotides (CNs) to RNA, enzymatic hydrolysis of endogenous RNA to release CNs, and off-line enrichment of CNs by ion-pairing high-pressure liquid chromatography, followed by a 17 min chromatography-coupled tandem quadrupole mass spectrometry run for the identification and quantification of individual CNs. The total time required for the protocol can be up to 7 d. In this approach, 26 CNs can be quantified in eukaryotic poly(A)-tailed RNA, bacterial total RNA and viral RNA. This protocol can be modified to analyze other types of RNA and RNA from in vitro sources. CapQuant stands out from other methods in terms of superior specificity, sensitivity and accuracy, and it is not limited to individual caps nor does it require radiolabeling. Thanks to its unique capability of accurately and sensitively quantifying RNA caps on a systems level, CapQuant can reveal both the RNA cap landscape and the transcription start site distribution of capped RNA in a broad range of settings.

Structural basis for the inhibitory mechanism of auranofin and gold(I) analogues against Pseudomonas aeruginosa global virulence factor regulator Vfr.

Pseudomonas aeruginosa is a leading cause of hospital-acquired infections. Treatment of P. aeruginosa infections is difficult given its multiple virulence mechanisms, intrinsic antibiotic resistance mechanisms, and biofilm-forming ability. Auranofin, an approved oral gold compound for rheumatoid arthritis treatment, was recently reported to inhibit the growth of multiple bacterial species. Here, we identify P. aeruginosa's global virulence factor regulator Vfr as one target of auranofin. We report the mechanistic insights into the inhibitory mechanism of auranofin and gold(I) analogues to Vfr through structural, biophysical, and phenotypic inhibition studies. This work suggests that auranofin and gold(I) analogues have potential to be developed as anti-virulence drugs against P. aeruginosa.

Flavivirus nonstructural proteins and replication complexes as antiviral drug targets.

Many flaviviruses are well-known pathogens, such as dengue, Zika, Japanese encephalitis, and yellow fever viruses. Among them, dengue viruses cause global epidemics and threaten billions of people. Effective vaccines and antivirals are in desperate need. In this review, we focus on the recent advances in understanding viral nonstructural (NS) proteins as antiviral drug targets. We briefly summarize the experimental structures and predicted models of flaviviral NS proteins and their functions. We highlight a few well-characterized inhibitors targeting these NS proteins and provide an update about the latest development. NS4B emerges as one of the most promising drug targets as novel inhibitors targeting NS4B and its interaction network are entering clinical studies. Studies aiming to elucidate the architecture and molecular basis of viral replication will offer new opportunities for novel antiviral discovery. Direct-acting agents against dengue and other pathogenic flaviviruses may be available very soon.

Tooth autotransplantation with 3D-printed replicas as part of interdisciplinary management of children and adolescents: Two case reports.

The management of missing teeth as a result of dental trauma or associated with hypodontia in children and adolescents presents as a clinical challenge for the dental team. One of the options that is regaining popularity is dental autotransplantation. To improve autotransplantation outcomes, careful interdisciplinary planning, surgical simulation using cone beam computed tomography images and three-dimensional-printed teeth replicas should be undertaken for presurgical preparation. This case report showcases two applications of autotransplantation, with emphasis on interdisciplinary management, presurgical preparation and postsurgical orthodontic and aesthetic management to deliver a good long-term, sustainable, biological outcome, as a part of a comprehensive rehabilitation treatment plan in children.

Tooth autotransplantation: An umbrella review.

Tooth autotransplantation is a versatile procedure with several clinical applications among patients across different age groups. The success of this procedure depends on multiple factors. Despite the wealth of studies available, no single primary study or systematic review is able to report on every factor affecting the outcomes of autotransplantation. The aims of this umbrella review were to evaluate treatment-related and patient-related outcomes of autotransplantation and to assess the pre-, peri- or post-operative factors that could affect these. An umbrella review was conducted according to the PRISMA statement. A literature search of five databases was performed up to 25 September 2022. Systematic Reviews (SR) with and without meta-analysis evaluating autotransplantation were included. Calibration among reviewers was carried out prior to study selection, data extraction and Risk of Bias (RoB) assessment. Study overlap was calculated using corrected covered area. Meta-meta-analysis (MMA) was performed for suitable SRs. The AMSTAR 2 critical appraisal tool was used to evaluate the quality of evidence. Seventeen SRs met the inclusion criteria. Only two SRs were suitable for conduct of MMA on autotransplantation of open apex teeth. The 5-year and 10-year survival rates were >95%. A narrative summary on factors that could affect autotransplantation outcomes and comparisons of autotransplantation to other treatment options were reported. Five SRs were rated as 'low quality' and 12 SRs were rated as 'critically low quality' in the AMSTAR 2 RoB assessment. In order to facilitate a more homogenous pool of data for subsequent meta-analysis, an Autotransplantation Outcome Index was also proposed to standardise the definition of outcomes. Autotransplantation of teeth with open apices have a high survival rate. Future studies should standardise the reporting of clinical and radiographic findings, as well as the definition of outcomes.

Analytical method for calculating internal stray radiation from an IR spectrometer based on the view factor.

Optomechanical components such as the lens barrels and frames of IR spectrometers produce strong internal stray radiation, which reduces the instrument's SNR and dynamic range. An IR internal stray radiation calculation method based on an analytical model of the view factor is proposed. The mathematical model of the view factor calculation method of typical optomechanical components is established. For any IR optical systems, the internal stray radiation can be quickly and accurately calculated by adjusting the coordinate systems in the calculation method. Based on the proposed method, the internal stray radiation of a double-pass long-wave IR spectrometer was calculated. The calculation results are consistent with the simulation results. The RMS value of the relative error between the calculated value and the simulated value is around 11%. To verify the proposed method, an experiment was conducted to test the internal stray radiation of the long-wave IR spectrometer. The internal stray radiation test results agree with the calculated and simulated results, and the relative error between the test results and the calculation results is within 9%.

Outcomes of preformed metal crowns placed with the conventional and Hall techniques: A systematic review and meta-analysis.

BACKGROUND: Preformed metal crowns (PMCs) have been used to restore carious primary molars and have a high success and survival rate. There are two methods currently employed for PMC placement - the conventional technique (CT) and Hall technique (HT). AIM: This systematic review aims to compare the outcomes of PMCs placed using the CT and HT. DESIGN: This systematic review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-analysis statement. A literature search of five databases was performed up to 23 August 2022. Clinical studies comparing carious primary molars restored with PMCs using either technique with a minimum 12-month follow-up were included. Risk of bias (RoB) assessment was performed using the National Institutes of Health Quality Assessment tool. RESULTS: Five articles met the inclusion criteria, and four were included for meta-analysis. The 12- and 24-month success and survival rates were above 85% for both groups, with no significant differences shown at 12 and 24 months. The HT requires a shorter treatment duration, is more cost-effective and has a high level of acceptability among parents when compared to the CT. Four articles were rated fair, and one article was rated good in the RoB assessment. CONCLUSION: Greater consideration may be given towards using the HT as part of standard treatment procedures in managing carious primary molars. Future studies should standardise reporting of outcomes to facilitate a more homogeneous pool of data for future meta-analysis.

Advances and challenges in using nirmatrelvir and its derivatives against SARS-CoV-2 infection / 药物分析学报

On December 22,2021,the United States Food and Drug Administration approved the first main protease inhibitor,i.e.,oral antiviral nirmatrelvir(PF-07321332)/ritonavir(Paxlovid),for the treatment of early severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection.Nirmatrelvir inhibits SARS-CoV-2 infection,but high doses or long-term treatment may cause embryonic developmental toxicity and changes in host gene expression.The chiral structure of nirmatrelvir plays a key role in its antiviral activity.Ritonavir boosts the efficacy of nirmatrelvir by inactivating cytochrome P450 3A4 expression and occupying the plasma protein binding sites.Multidrug resistance protein 1 inhibitors may increase the efficacy of nirmatrelvir.However,Paxlovid has many contraindications.Some patients treated with Paxlovid experience a second round of coronavirus disease 2019(COVID-19)symptoms soon after re-covery.Interestingly,the antiviral activity of nirmatrelvir metabolites,such as compounds 12-18,is similar to or higher than that of nirmatrelvir.Herein,we review the advances and challenges in using nirmatrelvir and its derivatives with the aim of providing knowledge for drug developers and physicians in the fight against COVID-19.

Effectiveness and Safety of Chinese Medicine at Shenque (CV 8) for Primary Dysmenorrhea: A Systematic Review and Meta-Analysis of Randomized Controlled Trials / 中国结合医学杂志

BACKGROUND@#Primary dysmenorrhea (PD) is the most common complaint associated with menstruation and affects up to three-quarters of women at some stage of their reproductive life. In Chinese medicine, navel therapy, treatment provided at Shenque (CV 8), is used as a treatment option for PD.@*OBJECTIVE@#To evaluate the effect of navel therapy on pain relief and quality of life in women with PD, compared with Western medicine (WM).@*METHODS@#China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), SinoMed and Wanfang Database, MEDLINE, the Cochrane Library, Embase, Web of Science, and the International Clinical Trial Registry of the U.S. National Institutes of Health were searched from their inceptions to April 1, 2021. Randomized controlled trials (RCTs) assessing therapeutic effects of navel therapy on PD were eligible for inclusion. RevMan 5.4 software was used for data analyses. The certainty of the evidence was assessed using the online GRADEpro tool.@*RESULTS@#Totally 24 RCTs involving 2,614 participants were identified. Interventions applied to acupuncture point CV 8 included: herbal patching, moxibustion or combined navel therapy (using at least 2 types of stimulation). Compared to placebo, there was a significant effect in favor of navel therapy on reducing overall menstrual symptom scores at the end of treatment [mean difference: -0.82, 95% confidence interval (CI): -1.00 to -0.64, n=90; 1 RCT]. As compared with Western medicine, navel therapy had a superior effect on pain intensity as assessed by Visual Analogue Scale at the end of treatment [standardized mean difference (SMD): -0.64, 95% CI: -1.22 to -0.06, I2=80%, n=262; 3 RCTs]; on symptom resolution rate at 3-month follow-up (risk ratio: 1.94, 95% CI: 1.47 to 2.56, n=1527, I2=38%; 13 RCTs); and on global menstrual symptoms score at the end of treatment (SMD: -0.67, 95% CI: -0.90 to -0.45, I2=63%, n=990; 12 RCTs). Subgroup analyses showed either a better or an equivalent effect comparing navel therapy with Western medicine. No major adverse events were reported. The methodological quality of included trials was poor overall.@*CONCLUSIONS@#Navel therapy appears to be more effective than Western medicine in decreasing menstrual pain and improving overall symptoms of PD. However, these findings need to be confirmed by well-designed clinical trials with adequate sample size (Systematic review registration at PROSPERO, No. CRD42021240350).