Mitochondria, the primary energy-producing organelles of the cell, also serve as signaling hubs and participate in diverse physiological and pathological processes, including apoptosis, inflammation, oxidative stress, neurodegeneration, and tumorigenesis. As semi-autonomous organelles, mitochondrial functionality relies on nuclear support, with mitochondrial biogenesis and homeostasis being stringently regulated by the nuclear genome. This interdependency forms a bidirectional signaling network that coordinates cellular energy metabolism, gene expression, and functional states. During mitochondrial damage or dysfunction, retrograde signals are transmitted to the nucleus, activating adaptive transcriptional programs that modulate nuclear transcription factors, reshape nuclear gene expression, and reprogram cellular metabolism. This mitochondrion-to-nucleus communication, termed “mitochondrial retrograde signaling”, fundamentally represents a mitochondrial “request” to the nucleus to maintain organellar health, rooted in the semi-autonomous nature of mitochondria. Despite possessing their own genome, the “fragmented” mitochondrial genome necessitates reliance on nuclear regulation. This genomic incompleteness enables mitochondria to sense and respond to cellular and environmental stressors, generating signals that modulate the functions of other organelles, including the nucleus. Evolutionary transfer of mitochondrial genes to the nuclear genome has established mitochondrial control over nuclear activities via retrograde communication. When mitochondrial dysfunction or environmental stress compromises cellular demands, mitochondria issue retrograde signals to solicit nuclear support. Studies demonstrate that mitochondrial retrograde signaling pathways operate in pathological contexts such as oxidative stress, electron transport chain (ETC) impairment, apoptosis, autophagy, vascular tension, and inflammatory responses. Mitochondria-related diseases exhibit marked heterogeneity but invariably result in energy deficits, preferentially affecting high-energy-demand tissues like muscles and the nervous system. Consequently, mitochondrial dysfunction underlies myopathies, neurodegenerative disorders, metabolic diseases, and malignancies. Dysregulated retrograde signaling triggers proliferative and metabolic reprogramming, driving pathological cascades. Mitochondrial retrograde signaling critically influences tumorigenesis and progression. Tumor cells with mitochondrial dysfunction exhibit compensatory upregulation of mitochondrial biogenesis, excessive superoxide production, and ETC overload, collectively promoting metastatic tumor development. Recent studies reveal that mitochondrial retrograde signaling—mediated by altered metabolite levels or stress signals—induces epigenetic modifications and is intricately linked to tumor initiation, malignant progression, and therapeutic resistance. For instance, mitochondrial dysfunction promotes oncogenesis through mechanisms such as epigenetic dysregulation, accumulation of mitochondrial metabolic intermediates, and mitochondrial DNA (mtDNA) release, which activates the cytosolic cGAS-STING signaling pathway. In normal cells, miR-663 mediates mitochondrion-to-nucleus retrograde signaling under reactive oxygen species (ROS) regulation. Mitochondria modulate miR-663 promoter methylation, which governs the expression and supercomplex stability of nuclear-encoded oxidative phosphorylation (OXPHOS) subunits and assembly factors. However, dysfunctional mitochondria induce oxidative stress, elevate methyltransferase activity, and cause miR-663 promoter hypermethylation, suppressing miR-663 expression. Mitochondrial dysfunction also triggers retrograde signaling in primary mitochondrial diseases and contributes to neurodegenerative disorders such as Parkinson’s disease (PD) and Alzheimer’s disease (AD). Current therapeutic strategies targeting mitochondria in neurological diseases focus on 5 main approaches: alleviating oxidative stress, inhibiting mitochondrial fission, enhancing mitochondrial biogenesis, mitochondrial protection, and insulin sensitization. In AD patients, mitochondrial morphological abnormalities and enzymatic defects, such as reduced pyruvate dehydrogenase and α-ketoglutarate dehydrogenase activity, are observed. Platelets and brains of AD patients exhibit diminished cytochrome c oxidase (COX) activity, correlating with mitochondrial dysfunction. To model AD-associated mitochondrial pathology, researchers employ cybrid technology, transferring mtDNA from AD patients into enucleated cells. These cybrids recapitulate AD-related mitochondrial phenotypes, including reduced COX activity, elevated ROS production, oxidative stress markers, disrupted calcium homeostasis, activated stress signaling pathways, diminished mitochondrial membrane potential, apoptotic pathway activation, and increased Aβ42 levels. Furthermore, studies indicate that Aβ aggregates in AD and α‑synuclein aggregates in PD trigger mtDNA release from damaged microglial mitochondria, activating the cGAS-STING pathway. This induces a reactive microglial transcriptional state, exacerbating neurodegeneration and cognitive decline. Targeting the cGAS-STING pathway may yield novel therapeutics for neurodegenerative diseases like AD, though translation from bench to bedside remains challenging. Such research not only deepens our understanding of disease mechanisms but also informs future therapeutic strategies. Investigating the triggers, core molecular pathways, and regulatory networks of mitochondrial retrograde signaling advances our comprehension of intracellular communication and unveils novel pathogenic mechanisms underlying malignancies, neurodegenerative diseases, and type 2 diabetes mellitus. This review summarizes established mitochondrial-nuclear retrograde signaling axes, their roles in interorganellar crosstalk, and pathological consequences of dysregulated communication. Targeted modulation of key molecules and proteins within these signaling networks may provide innovative therapeutic avenues for these diseases.

ObjectiveThe proteome of biological evidence contains rich genetic information, namely single amino acid polymorphisms (SAPs) in protein sequences. However, due to the lack of efficient and convenient analysis tools, the application of SAP in public security still faces many challenges. This paper aims to meet the application requirements of SAP analysis for forensic biological evidence’s proteome data. MethodsThe software is divided into three modules. First, based on a built-in database of common non-synonymous single nucleotide polymorphisms (nsSNPs) and SAPs in East Asian populations, the software integrates and annotates newly identified exonic nsSNPs as SAPs, thereby constructing a customized SAP protein sequence database. It then utilizes a pre-installed search engine—either pFind or MaxQuant—to perform analysis and output SAP typing results, identifying both reference and variant types, along with their corresponding imputed nsSNPs. Finally, SAPTyper compares the proteome-based typing results with the individual’s exome-derived nsSNP profile and outputs the comparison report. ResultsSAPTyper accepts proteomic DDA mass spectrometry raw data (DDA acquisition mode) and exome sequencing results of nsSNPs as input and outputs the report of SAPs result. The pFind and Maxquant search engines were used to test the proteome data of 2 hair shafts of2 individuals, and both obtained SAP results. It was found that the results of the Maxquant search engine were slightly less than those of pFind. This result shows that SAPTyper can achieve SAP fingding function. Moreover, the pFind search engine was used to test the proteome data of 3 hair shafts from 1 European person and 1 African person in the literature. Among the sites fully matched by the literature method, sites detected by SAPTyper are also included; for semi-matching sites, that is, nsSNPs are heterozygous, both literature method and SAPTyper method had the risk of missing detection for one type of the allele. Comparing the analysis results of SAPTyper with the SAP test results reported in the literature, it was found that some imputed nsSNP sites identified by the literature method but not detected by SAPTyper had a MAF of less than 0.1% in East Asian populations, and therefore they were not included in the common nsSNP database of East Asian populations constructed by this software. Since the database construction of this software is based on the genetic variation information of East Asian populations, it is currently unable to effectively identify representative unique common variation sites in European or African populations, but it can still identify SAP sites shared by these populations and East Asian populations. ConclusionAn automated SAP analysis algorithm was developed for East Asian populations, and the software named SAPTyper was developed. This software provides a convenient and efficient analysis tool for the research and application of forensic proteomic SAP and has important application prospects in individual identification and phenotypic inference based on SAP.

OBJECTIVE: To investigate the characteristics of gut microbiota changes in patients with acute myeloid leukemia (AML) undergoing induction chemotherapy and to explore the relationship between infectious complications and gut microbiota. METHODS: Fecal samples were collected from 37 newly diagnosed AML patients at four time points: before induction chemotherapy, during chemotherapy, during the neutropenic phase, and during the recovery phase. Metagenomic sequencing was used to analyze the dynamic changes in gut microbiota. Correlation analyses were conducted to assess the relationship between changes in gut microbiota and the occurrence of infectious complications. RESULTS: During chemotherapy, the gut microbiota α-diversity (Shannon index) of AML patients exhibited significant fluctuations. Specifically, the diversity decreased significantly during induction chemotherapy, further declined during the neutropenic phase (P < 0.05, compared to baseline), and gradually recovered during the recovery phase, though not fully returning to baseline levels.The abundances of beneficial bacteria, such as Firmicutes and Bacteroidetes, gradually decreased during chemotherapy, whereas the abundances of opportunistic pathogens, including Enterococcus, Klebsiella, and Escherichia coli, progressively increased.Analysis of the dynamic changes in gut microbiota of seven patients with bloodstream infections revealed that the bloodstream infection pathogens could be detected in the gut microbiota of the corresponding patients, with their abundance gradually increasing during the course of infection. This finding suggests that bloodstream infections may be associated with opportunistic pathogens originating from the gut microbiota.Compared to non-infected patients, the baseline samples of infected patients showed a significantly lower relative abundance of Bacteroidetes (P < 0.05). Regression analysis indicated that Bacteroidetes abundance is an independent predictive factor for infectious complications (P < 0.05, OR =13.143). CONCLUSION During induction chemotherapy in AML patients, gut microbiota α-diversity fluctuates significantly, and the abundance of opportunistic pathogens increase, which may be associated with bloodstream infections. Patients with lower baseline Bacteroidetes abundance are more prone to infections, and its abundance can serve as an independent predictor of infectious complications.
Humans ; Gastrointestinal Microbiome ; Leukemia, Myeloid, Acute/microbiology* ; Induction Chemotherapy ; Feces/microbiology* ; Male ; Female ; Middle Aged

BACKGROUND: Atrial fibrillation (AF) is a common cardiac arrhythmia in the elderly. This study aimed to evaluate urban-rural disparities in its prevalence and management in elderly Chinese. METHODS: Consecutive participants aged ≥ 65 years attending outpatient clinics were enrolled for AF screening using handheld single-lead electrocardiogram (ECG) from April 2017 to December 2022. Each ECG rhythm strip was reviewed from the research team. AF or uninterpretable single-lead ECGs were referred for 12-lead ECG. Primary study outcome comparison was between rural and urban areas for the prevalence of AF. The Student's t-test was used to compare mean values of clinical characteristics between rural and urban participants, while the Pearson's chi-square test was used to compare between-group proportions. Multivariate stepwise logistic regression analysis was performed to estimate the association between AF and various patient characteristics. RESULTS: The 29,166 study participants included 13,253 men (45.4%) and had a mean age of 72.2 years. The 7073 rural participants differed significantly (P ≤ 0.02) from the 22,093 urban participants in several major characteristics, such as older age, greater body mass index, and so on. The overall prevalence of AF was 4.6% (n = 1347). AF was more prevalent in 7073 rural participants than 22,093 urban participants (5.6% vs. 4.3%, P < 0.01), before and after adjustment for age, body mass index, blood pressure, pulse rate, cigarette smoking, alcohol consumption and prior medical history. Multivariate logistic regression analysis identified overweight/obesity (OR = 1.35, 95% CI: 1.17-1.54) in urban areas and cigarette smoking (OR = 1.62, 95% CI: 1.20-2.17) and alcohol consumption (OR = 1.42, 95% CI: 1.04-1.93) in rural areas as specific risk factors for prevalent AF. In patients with known AF in urban areas (n = 781) and rural areas (n = 338), 60.6% and 45.9%, respectively, received AF treatment (P < 0.01), and only 22.4% and 17.2%, respectively, received anticoagulation therapy (P = 0.05). CONCLUSIONS In China, there are urban-rural disparities in AF in the elderly, with a higher prevalence and worse management in rural areas than urban areas. Our study findings provide insight for health policymakers to consider urban-rural disparity in the prevention and treatment of AF.

OBJECTIVES: Chronic obstructive pulmonary disease (COPD) is a major chronic respiratory condition with high morbidity and mortality, imposing a serious economic and public health burden. The World Health Organization ranks COPD among the top 4 chronic diseases worldwide. Zangsiwei Qingfei Mixture (ZSWQF), a novel Tibetan herbal formulation independently developed by our research team, has shown therapeutic potential for chronic respiratory diseases. This study aims to evaluate the effects of aerosolized ZSWQF on cigarette smoke-induced COPD in mice and explore its underlying mechanisms. METHODS: Thirty C57 mice were randomly divided into a Control group, a COPD group, and a ZSWQF group. The Control group received saline aerosol inhalation without cigarette smoke exposure; both the COPD group and the ZSWQF group were exposed to cigarette smoke, with the former receiving saline inhalation and the latter treated with ZSWQF aerosol. White blood cell (WBC) count was performed using a fully automatic blood cell analyzer. Serum, alanine transaminase (ALT), and serum creatinine (SCr), as well as interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α levels in serum and bronchoalveolar lavage fluid (BALF) were measured by enzyme-linked immunosorbent assay (ELISA). BALF cell classification was determined using a hematology analyzer. Lung function was assessed with a small animal pulmonary function system, including airway resistance (RI) and cyclic dynamic compliance (CyDN). Lung tissues were stained with hematoxylin and eosin (HE), and mean linear intercept (MLI) and destruction index (DI) were calculated to evaluate morphological changes. Network pharmacology was applied to identify disease-related and ZSWQF-related targets, followed by intersection and protein-protein interaction (PPI) network analysis, and enrichment analysis of biological functions and pathways. Primary type II alveolar epithelial cell (AEC II) from SD rats were isolated and divided into a Control group, a lipopolysaccharide (LPS) group, a normal serum group, a water extract of ZSWQF (W-ZSWQF) group, a ZSWQF containing serum group, and a MLN-4760 [angiotensin-converting enzyme (ACE) 2 inhibitor]. Western blotting was performed to assess protein expression of ACE, p38 [a mitogen-activated protein kinase (MAPK)], phospho (p)-p38, extracellular signal-regulated kinases 1 and 2 (ERK1/2), p-ERK1/2, c-Jun N-terminal kinase (JNK), p-JNK, inhibitor of nuclear factor-kappa B alpha (IκBα), p-IκBα, and p-p65 subunit of nuclear factor-kappa B (NF-κBp65). RESULTS: WBC counts were significantly higher in the COPD group than in controls (P<0.01) and decreased following ZSWQF treatment (P<0.05). No significant intergroup differences were found in organ weights, ALT, or SCr (all P>0.05). Serum and BALF levels of IL-6, IL-8, and TNF-α, as well as total BALF cells, neutrophils, and macrophages, were elevated in the COPD group compared with controls and reduced by ZSWQF treatment (P<0.05). COPD mice exhibited increased RI, decreased CyDN, marked alveolar congestion, inflammatory infiltration, thickened septa, and higher MLI and DI values versus controls (P<0.05); ZSWQF treatment significantly reduced MLI and DI (P<0.05). Network pharmacology identified 151 potential therapeutic targets for ZSWQF against COPD, with key nodes including TNF, IL-6, protein kinase B (Akt) 1, albumin (ALB), tumor protein p53 (TP53), non-receptor tyrosine kinase (SRC), epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT) 3, matrix metalloproteinase (MMP)-9, and beta-catenin (CTNNB1). Enrichment analysis indicates involvement of cancer-related, phosphatidylinositol 3-kinase (PI3K)/Akt, hypoxia-inducible factor (HIF)-1, calcium, and MAPK signaling pathways. Western blotting results showed that compared with the LPS group, AEC II treated with ZSWQF-containing serum exhibited decreased expression of ACE, p-p38/p38, p-ERK1/2/ERK1/2, p-JNK/JNK, p-IκBα/IκBα, and p-NF-κBp65, while ACE2 expression was upregulated, consistent with the MAPK/nuclear factor-kappa B (NF-κB) pathway regulation predicted by network pharmacology. CONCLUSIONS Aerosolized ZSWQF provides protective effects in COPD mice by reducing airway inflammation and remodeling.
Animals ; Pulmonary Disease, Chronic Obstructive/etiology* ; Drugs, Chinese Herbal/therapeutic use* ; Mice ; Mice, Inbred C57BL ; Male ; Network Pharmacology ; Smoke/adverse effects* ; Bronchoalveolar Lavage Fluid ; Administration, Inhalation ; Inflammation/drug therapy* ; Tumor Necrosis Factor-alpha ; Lung/drug effects* ; Interleukin-6/blood*

Hepatic stellate cells (HSCs) are the primary fibrogenic cells in the liver, and their activation plays a crucial role in the development and progression of hepatic fibrosis. Here, we report that retinoid X receptor-alpha (RXRα), a unique member of the nuclear receptor superfamily, is a key modulator of HSC activation and liver fibrosis. RXRα exerts its effects by modulating calcium/calmodulin-dependent protein kinase kinase β (CaMKKβ)-mediated activation of AMP-activated protein kinase-alpha (AMPKα). In addition, we demonstrate that K-80003, which binds RXRα by a unique mechanism, effectively suppresses HSC activation, proliferation, and migration, thereby inhibiting liver fibrosis in the CCl₄ and amylin liver NASH (AMLN) diet animal models. The effect is mediated by AMPKα activation, promoting mitophagy in HSCs. Mechanistically, K-80003 activates AMPKα by inducing RXRα to form condensates with CaMKKβ and AMPKα via a two-phase process. The formation of RXRα condensates is driven by its N-terminal intrinsic disorder region and requires phosphorylation by CaMKKβ. Our results reveal a crucial role of RXRα in liver fibrosis regulation through modulating mitochondrial activities in HSCs. Furthermore, they suggest that K-80003 and related RXRα modulators hold promise as therapeutic agents for fibrosis-related diseases.

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.
Animals ; Autophagy/physiology* ; Oligodendroglia/metabolism* ; Myelin Sheath/physiology* ; Aging/pathology* ; Myelin Basic Protein/metabolism* ; Cell Lineage/physiology* ; Mice ; Oligodendrocyte Precursor Cells ; Mice, Inbred C57BL ; Brain/cytology* ; Cells, Cultured ; Cell Count

Enamel hypoplasia is a disease that results in enamel formation and mineralization abnormalities due to the effects of hereditary or environmental variables during tooth development.Affected teeth may appear to have an ab-errant color and structural flaws.Patients often display clinical signs such as tooth defects,tooth sensitivity,and tooth discoloration.The disease can cause patients to feel physically and mentally uncomfortable and negatively impact their ability to chew,swallow,speak,and smile.In this review,the pathophysiology of enamel hypoplasia,which is caused by anomalies in gene regulation and changes in environmental variables,is summarized,along with a list of clinical diag-nostic indicators based on the most commonly used disease classifications.The main points are as follows:① enamel hypoplasia changes only the color and transparency of the affected teeth;② lesions often occur symmetrically in groups;③ the age at which systemic diseases or nutritional disorders occur during tooth development can be predicted based on the patient's impaired teeth;and ④ banded or pitted brown depression on the enamel surface can easily be confused with dental fluorosis.It also elaborates on the comprehensive application of tooth bleaching,desensitization,direct or in-direct restoration and other treatment modalities according to unique chief complaints by different patients and suggests the use of multidisciplinary cooperative sequential treatment for critical infants and young children.The goal of this re-view is to provide professionals with the most recent information and advice about enamel hypoplasis.Current literature on this condition is primarily case reports.To further standardize the diagnostic and management approaches for this dis-ease,additional high-quality clinical research and systematic reviews are required.

Objective To explore the improve mechanism of ultra-filtration extract from Angelica Sinensis Radix and Hedysari Radix on kidney injury in diabetic kidney disease(DKD)rats.Methods The diabetes model was prepared by intraperitoneal injection of streptozotocin,and then fed with high sugar and high fat diet.The rats with successful DKD were randomly divided into model group,positive control group and experimental-L,-M,-H groups with 8 cases per group.Additionally,selected 8 Wistar rats as the blank group.The experimental-L,-M,-H groups were given 1.5,3.0 and 6.0 g·kg-1 ultra-filtration extract from Angelica Sinensis Radix and Hedysari Radix by gavage,respectively.The positive control group was given 1.75 × 10-3 g·kg-1irbesartan suspension by gavage.The blank and model groups were given equal volume of pure water by gavage.Six groups were administrated once a day for 12 consecutive weeks.The 24 h-urinary total protein were detected by coomassie brilliant blue method.The protein expression levels of nuclear factor erythroid 2-related factor 2(Nrf2),heme oxygenase-1(HO-1)and andacyl-CoA synthetase long chain family member 4(ACSL4)in kidney tissue were detected by Western blot.Results The 24 h-UTP in the experimental-M,-H groups,positive control group,model group and blank group were(47.70±3.85),(43.57±6.38),(36.80±6.52),(64.34±13.38)and(7.58±3.71)mg;the relative expression levels of Nrf2 protein were 0.86±0.08,0.75±0.06,0.64±0.08,1.09±0.06 and 0.60±0.07;the relative expression levels of HO-1 protein were 0.77±0.04,0.63±0.07,0.47±0.05,1.04±0.06 and 0.34±0.07;the relative expression levels of ACSL4 protein were 0.62±0.07,0.55±0.07,0.46±0.06,1.08±0.07 and 0.30±0.01,respectively.Compared with the model group,the above indexes in the experimental-M,-H groups and positive control group were significantly different(P＜0.05,P＜0.01).Conclusion Ultra-filtration extract from Angelica Sinensis Radix and Hedysari Radix can improve the damage of kidney tissue in DKD rats,and the mechanism may be related to ferroptosis caused by excessive activation of Nrf2/HO-1 signaling pathway.