Environmental triggers of autoimmunity: The association between bisphenol analogues and systemic lupus erythematosus.

The aim of this research was to examine the correlation between the exposure to bisphenol analogues (BPs), such as bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS), and the risk of developing systemic lupus erythematosus (SLE). Ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was utilized to measure the levels of BPA, BPF, and BPS in the urine of 168 female participants diagnosed with SLE and 175 female participants who were deemed healthy controls. Logistic regression models were utilized to assess the connections between levels of bisphenol and the risk of SLE. The findings indicated that levels of BPA and BPF in the urine of individuals with SLE were markedly elevated compared to those in the control group. Higher exposure to BPA and BPF exhibited positive dose-response relationships with increased SLE risk. No significant associations were identified between BPS and the risk of SLE. These findings suggest exposure to BPA and BPF may be implicated as novel environmental triggers in the development of autoimmunity such as SLE. The significantly increased levels of these bisphenol analogues detected in SLE patients versus healthy controls, along with the associations between higher exposures and elevated SLE risk, which offers crucial hints for comprehending how endocrine-disrupting substances contribute to the genesis of autoimmune illnesses. Further research using robust longitudinal assessments of bisphenol analogue exposures is warranted to corroborate these epidemiological findings. Overall, this study highlights potential environmental risk factors for SLE while calling for additional investigation into the impact of bisphenol exposures on autoimmunity development.

No causal association between pneumoconiosis and three inflammatory immune diseases: a Mendelian randomization study.

Objectives: To investigate the causal relationships between pneumoconiosis and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and gout. Methods: The random-effects inverse variance weighted (IVW) approach was utilized to explore the causal effects of the instrumental variables (IVs). Sensitivity analyses using the MR-Egger and weighted median (WM) methods were did to investigate horizontal pleiotropy. A leave-one-out analysis was used to avoid the bias resulting from single-nucleotide polymorphisms (SNPs). Results: There was no causal association between pneumoconiosis and SLE, RA or gout in the European population [OR = 1.01, 95% CI: 0.94-1.10, p = 0.74; OR = 1.00, 95% CI: 0.999-1.000, p = 0.50; OR = 1.00, 95% CI: 1.000-1.001, p = 0.55]. Causal relationships were also not found in pneumoconiosis due to asbestos and other mineral fibers and SLE, RA and gout [OR = 1.01, 95% CI: 0.96-1.07, p = 0.66; OR = 1.00, 95% CI: 1.00-1.00, p = 0.68; OR = 1.00, 95% CI: 1.00-1.00, p = 0.20]. Conclusion: Our study suggests that pneumoconiosis may have no causal relationship with the three inflammatory immune diseases.

Endocrine-disrupting chemicals and autoimmune diseases.

Endocrine-disrupting chemicals (EDCs) widely exist in people's production and life which have great potential to damage human and animal health. Over the past few decades, growing attention has been paid to the impact of EDCs on human health, as well as immune system. So far, researchers have proved that EDCs (such as bisphenol A (BPA), phthalate, tetrachlorodibenzodioxin (TCDD), etc.) affect human immune function and promotes the occurrence and development of autoimmune diseases (ADs). Therefore, in order to better understand how EDCs affect ADs, we summarized the current knowledge about the impact of EDCs on ADs, and elaborated the potential mechanism of the impact of EDCs on ADs in this review.

Suicide and suicidality in people exposed to pesticides: A systematic review and meta-analysis.

Exposure to pesticides has been proposed to be a positive association in suicide and suicidality. Many studies have explored this topic, but have reported inconsistent findings. We carried out a systematic review and meta-analysis of the now existing evidence on the association between pesticide exposure and the risk of suicide and suicidality. We searched PubMed, EMBASE and Web of Science databases for studies published up to February 1, 2023. For studies that provided detailed data, we applied quantitative meta-analysis to calculate Odds ratio (OR) with 95% Confidence Intervals (CIs) to evaluate the results. Heterogeneity among the included studies was assessed using Cochran's Q test, I2 statistic and tau-squared (τ2). Publication bias was evaluated by funnel plots, Egger's test, and Begg's test. In addition, subgroup analyses according to pesticides category and geographical area were performed. 2906 studies were initially identified, and 20 studies were eventually included. Fifteen of the studies were on suicide deaths and suicide attempts, and five were on suicidal ideation. Pesticide exposure was positively related to suicide deaths and suicide attempts (pooled OR = 1.31; 95%CI: 1.04-1.64, p < 0.001) and suicidal ideation (pooled OR = 2.43; 95%CI: 1.51-3.91, p = 0.015). In the subgroup analysis, mixed pesticide type (pooled OR = 1.55; 95%CI: 1.39-1.74) increased the risk of suicide deaths and suicide attempts. The results of the analysis by geographic area showed that the risk of suicide deaths and suicide attempts with pesticide exposure was 2.27 (95%CI = 1.36-3.78), and 1.33 (95%CI = 1.14-1.56) in Asia and Europe, respectively. The risk of suicidal ideation caused by pesticide exposure in Asia and America were 2.19 (95%CI = 1.08-4.42) and 2.99 (95%CI = 1.76-5.06). In conclusion, pesticide exposure may increase the risk of suicide and suicidality based on the current evidence.

Intestinal fungi and systemic autoimmune diseases.

Nearly 20 years of studies have shown that fungi and the human immune system (non-specific immunity and specific immunity) and bacterial--fungal interactions maintain a balance that can't lead to diseases. Fungi--microorganism that lives in human intestine--may play an important role in human health and disease. Population studies and animal models in some diseases have found the changes in the diversity and composition of fungi. The dysregulation of the fungi can disrupt the normal "running" of the immune system and bacteria, which triggers the development of inflammatory diseases. The latest studies of fungi in inflammatory bowel disease, systemic lupus erythematosus, ankylosing spondylitis and type 1 diabetes mellitus were summarized. This review considers how the healthy host protect against the potential harm of intestinal fungi through the immune system and how fungal dysregulation alters host immunity.

Essential Trace Element Status in Systemic Lupus Erythematosus: a Meta-analysis Based on Case-Control Studies.

The homeostasis of trace elements is essential to regulate different aspects of the immune system and might play important roles in systemic lupus erythematosus (SLE). However, epidemiological evidences that compared the level of essential trace elements in SLE patients and healthy controls (HCs) did not reach a consensus. This was the first meta-analysis to comprehensively assess the level of zinc (Zn), copper (Cu), iron (Fe), and selenium (Se) in SLE and HCs. PubMed, Embase, and Web of Science were systematically searched until April 2022 to find relevant literatures. The PRISMA statement 2020 was followed to make sure the quality of reporting a meta-analysis. The outcomes were assessed by pooled standardized mean difference (SMD) and 95% confidence intervals (CIs). Finally, eleven articles with 1262 subjects were included in the meta-analysis. Significantly lower levels of Zn (SMD = -0.709; 95% CI: -1.173, -0.245; P = 0.003) and Fe (SMD = -1.783; 95% CI: -2.756, -0.809; P = 0.000) were found in SLE compared with HCs. Higher levels of Cu (SMD = 0.808; 95% CI: 0.234, 1.382; P = 0.006) were found in SLE patients. In addition, compared with HCs, Fe and Zn were lower in SLE patients in Asia and Cu was higher in SLE patients in Europe. However, no significant difference was observed in the level of Se (SMD = -0.251; 95% CI: -1.087, 0.586; P = 0.557). Above all, SLE patients exhibited lower Zn and Fe and increased Cu concentrations compared with HCs. Further studies are warranted to investigate the mechanism of Zn, Cu, and Fe in SLE patients.

Altered gut fungi in systemic lupus erythematosus - A pilot study.

Objective: Gut fungi, as symbiosis with the human gastrointestinal tract, may regulate physiology via multiple interactions with host cells. The plausible role of fungi in systemic lupus erythematosus (SLE) is far from clear and need to be explored. Methods: A total of 64 subjects were recruited, including SLE, rheumatoid arthritis (RA), undifferentiated connective tissue diseases (UCTDs) patients and healthy controls (HCs). Fecal samples of subjects were collected. Gut fungi and bacteria were detected by ITS sequencing and 16S rRNA gene sequencing, respectively. Alpha and beta diversities of microbiota were analyzed. Linear discriminant analysis effect size analysis was performed to identify abundance of microbiota in different groups. The correlation network between bacterial and fungal microbiota was analyzed based on Spearman correlation. Results: Gut fungal diversity and community composition exhibited significant shifts in SLE compared with UCTDs, RA and HCs. Compared with HCs, the alpha and beta diversities of fungal microbiota decreased in SLE patients. According to principal coordinates analysis results, the constitution of fungal microbiota from SLE, RA, UCTDs patients and HCs exhibited distinct differences with a clear separation between fungal microbiota. There was dysbiosis in the compositions of fungal and bacterial microbiota in the SLE patients, compared to HCs. Pezizales, Cantharellales and Pseudaleuria were enriched in SLE compared with HCs, RA and UCTDs. There was a complex relationship network between bacterial and fungal microbiota, especially Candida which was related to a variety of bacteria. Conclusion: This study presents a pilot analysis of fungal microbiota with diversity and composition in SLE, and identifies several gut fungi with different abundance patterns taxa among SLE, RA, UCTDs and HCs. Furthermore, the gut bacterial-fungal association network in SLE patients was altered compared with HCs.

Synchronous resection of 12 small pulmonary nodules guided by a noninvasive 3D printed emulation model: A case report.

Localization of multiple small pulmonary nodules is the major obstacle in surgical resection. Here, we report a novel noninvasive localization technique based on a life-size 3D printed "emulation pulmonary nodule localization model" which is simple and efficient. In the case reported here of a patient with synchronous multiple pulmonary nodules, the nodules were successfully and conveniently localized without any trauma by navigation of the emulation localization model. All 12 nodules were resected precisely and thoroughly, while normal lung tissues were considerably well preserved. Pathological examination confirmed malignancy of the major nodule and some other small nodules.

Correlation Between Brain Structure Atrophy and Plasma Amyloid-ß and Phosphorylated Tau in Patients With Alzheimer's Disease and Amnestic Mild Cognitive Impairment Explored by Surface-Based Morphometry.

Objective: To investigate the changes in the cortical thickness of the region of interest (ROI) and plasma Aß40, Aß42, and phosphorylated Tau (P-Tau) concentrations in patients with Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI) as the disease progressed with surface-based morphometry (SBM), to analyze the correlation between ROI cortical thickness and measured plasma indexes and neuropsychological scales, and to explore the clinical value of ROI cortical thickness combined with plasma Aß40, Aß42, and P-Tau in the early recognition and diagnosis of AD. Methods: This study enrolled 33 patients with AD, 48 patients with aMCI, and 33 healthy controls (normal control, NC). Concentration changes in plasma Aß42, Aß40, and P-Tau collected in each group were analyzed. Meanwhile, the whole brain T1 structure images (T1WI-3D-MPRAGE) of each group of patients were collected, and T1 image in AD-aMCI, AD-NC, and aMCI-NC group were analyzed and processed by SBM technology to obtain brain regions with statistical differences as clusters, and the cortical thickness of each cluster was extracted. Multivariate ordered logistic regression analysis was used to screen out the measured plasma indexes and the indexes with independent risk factors in the cortical thickness of each cluster. Three comparative receiver operating characteristic (ROC) curves of AD-aMCI, AD-NC, and aMCI-NC groups were plotted, respectively, to explore the diagnostic value of multi-factor combined prediction for cognitive impairment. The relationship between cortical thickness and plasma indexes, and between cortical thickness and Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) scores were clarified by Pearson correlation analysis. Results: Plasma Aß40, Aß42, and P-Tau proteins in the NC, aMCI, and AD groups increased with the progression of AD (P < 0.01); cortical thickness reductions in the AD-aMCI groups and AD-NC groups mainly involved the bilateral superior temporal gyrus, transverse temporal gyrus, superior marginal gyrus, insula, right entorhinal cortex, right fusiform gyrus, and cingulate gyrus. However, there were no statistical significances in cortical thickness reductions in the aMCI and NC groups. The cortical thickness of the ROI was negatively correlated with plasma Aß40, Aß42, and P-Tau concentrations (P < 0.05), and the cortical thickness of the ROI was positively correlated with MMSE and MoCA scores. Independent risk factors such as Aß40, Aß42, P-Tau, and AD-NC cluster 1R (right superior temporal gyrus, temporal pole, entorhinal cortex, transverse temporal gyrus, fusiform gyrus, superior marginal gyrus, middle temporal gyrus, and inferior temporal gyrus) were combined to plot ROC curves. The diagnostic efficiency of plasma indexes was higher than that of cortical thickness indexes, the diagnostic efficiency of ROC curves after the combination of cortical thickness and plasma indexes was higher than that of cortical thickness or plasma indexes alone. Conclusion: Plasma Aß40, Aß42, and P-Tau may be potential biomarkers for early prediction of AD. As the disease progressed, AD patients developed cortical atrophy characterized by atrophy of the medial temporal lobe. The combined prediction of these region and plasma Aß40, Aß42, and P-Tau had a higher diagnostic value than single-factor prediction for cognitive decline.

Machine Learning-Assisted Dual-Marker Detection in Serum Small Extracellular Vesicles for the Diagnosis and Prognosis Prediction of Non-Small Cell Lung Cancer.

Small extracellular vesicles (sEVs) carry molecular information from their source cells and are desired biomarkers for cancer diagnosis. We establish a machine learning-assisted dual-marker detection method to analyze the expression of epidermal growth factor receptor (EGFR) and C-X-C chemokine receptor 4 (CXCR4) in serum sEVs for the diagnosis and prognosis prediction of non-small cell lung cancer (NSCLC). We find that the serum sEV EGFR and CXCR4 are significantly higher in advanced stage NSCLC (A/NSCLC) patients compared to early stage NSCLC (E/NSCLC) patients and the healthy donors (HDs). A receiver operating characteristic curve (ROC) analysis demonstrates that the combination of EGFR and CXCR4 in serum sEVs as an efficient diagnostic index and malignant degree indicator for NSCLC. Machine learning further shows a diagnostic accuracy of 97.4% for the training cohort and 91.7% for the validation cohort based on the combinational marker. Moreover, this machine leaning-assisted serum sEV analysis successfully predicts the possibility of tumor relapse in three NSCLC patients by comparing their serum sEVs before and three days after surgery. This study provides an intelligent serum sEV-based assay for the diagnosis and prognosis prediction of NSCLC, and will benefit the precision management of NSCLC.

Perioperative ctDNA-Based Molecular Residual Disease Detection for Non-Small Cell Lung Cancer: A Prospective Multicenter Cohort Study (LUNGCA-1).

PURPOSE: We assessed whether perioperative circulating tumor DNA (ctDNA) could be a biomarker for early detection of molecular residual disease (MRD) and prediction of postoperative relapse in resected non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Based on our prospective, multicenter cohort on dynamic monitoring of ctDNA in lung cancer surgery patients (LUNGCA), we enrolled 950 plasma samples obtained at three perioperative time points (before surgery, 3 days and 1 month after surgery) of 330 stage I-III NSCLC patients (LUNGCA-1), as a part of the LUNGCA cohort. Using a customized 769-gene panel, somatic mutations in tumor tissues and plasma samples were identified with next-generation sequencing and utilized for ctDNA-based MRD analysis. RESULTS: Preoperative ctDNA positivity was associated with lower recurrence-free survival (RFS; HR = 4.2; P < 0.001). The presence of MRD (ctDNA positivity at postoperative 3 days and/or 1 month) was a strong predictor for disease relapse (HR = 11.1; P < 0.001). ctDNA-based MRD had a higher relative contribution to RFS prediction than all clinicopathologic variables such as the TNM stage. Furthermore, MRD-positive patients who received adjuvant therapies had improved RFS over those not receiving adjuvant therapy (HR = 0.3; P = 0.008), whereas MRD-negative patients receiving adjuvant therapies had lower RFS than their counterparts without adjuvant therapy (HR = 3.1; P < 0.001). After adjusting for clinicopathologic variables, whether receiving adjuvant therapies remained an independent factor for RFS in the MRD-positive population (P = 0.002) but not in the MRD-negative population (P = 0.283). CONCLUSIONS: Perioperative ctDNA analysis is effective in early detection of MRD and relapse risk stratification of NSCLC, and hence could benefit NSCLC patient management.

A noteworthy case of rewilding Chinese yew from a garden population in eastern China.

Chinese yew (Taxus wallichiana var. mairei) is ranked as a rare and endangered plant of first-grade protection of China. It has been widely cultivated in 17 provinces of China over the past few decades. However, little is known about the dispersion, rewilding, and ecological influence of Chinese yew's offspring during cultivation. Here, we report a noteworthy case of this species, via ex situ conservation, which has successfully spread into different secondary forests, thus forming a stable regenerating population in eastern China. The establishment of this yew population, which has > 900 individuals and 7 ha area, can be ascribed to two key ecological factors: (1) secondary forest near the parent yews that provided suitable microhabitats in which progeny yews could germinate and grow, and (2) seed-foraging and transportation by native birds. Thus, this case may offer a pathway for conserving endangered Chinese Taxus species, which can attract frugivorous birds to disperse their seeds. In addition, it is necessary to monitor the growth performance of progeny population in the field.

Gold nanoparticle enhanced detection of EGFR with a terahertz metamaterial biosensor.

The epidermal growth factor receptor (EGFR) plays an important role in the proliferation of various cancers, and the expression level of EGFR in tumor tissues can provide a basis for the diagnosis and prognosis. Improving the detection technology of EGFR to achieve high sensitivity and faster speed will benefit the diagnosis of many types of tumors. Trace biological samples can be sensitively measured with terahertz (THz) metamaterial devices. Here, a bow-tie array THz metamaterial biosensor is presented and modified with gold nanoparticles (GNPs) and EGFR antibodies for specific EGFR detection. The effect of the size of the GNP on the sensitivity enhancement was also analyzed. Enhanced sensing for EGFR was achieved with the assistance of GNPs and EGFR antibodies. Importantly, the metamaterial functionalized by GNPs and antibodies with a bigger GNP diameter achieves a greater resonance frequency shift. The proposed metamaterial biosensor can also realize tiny-volume EGFR solution detection. Our proposed technique can therefore sense EGFR sensitively with high speed, and can potentially be applied to achieve quick and accurate detection of EGFR related tumors.

Phytoplankton responses to solar UVR and its combination with nutrient enrichment in a plateau oligotrophic Lake Fuxian: a mesocosm experiment.

Multiple stressors associated with global change are influencing the phytoplankton taxonomic composition and biomass in plateau lakes, such as higher levels of ultraviolet radiation (UVR, 280-400 nm) and the risk of eutrophication. Although the restrictive effects of high UVR on phytoplankton are generally recognized, the effects will be impacted by the UVR levels of seasonal changes and the nutrient status. In this study, in situ phytoplankton productivity was measured seasonally under full solar radiation and only visible light (photosynthetically active radiation, PAR) conditions in the plateau oligotrophic Lake Fuxian, Southwest China. To determine the single effects of UVR and nutrient enrichment and their combined impact on phytoplankton communities, a mesocosm experiment (1 month) was conducted outdoors during late summer (rainy season). The interactive experiment was designed with two radiation treatments (UVR + PAR and PAR) and four nutrient treatments (raw water, nitrogen addition, phosphorus addition, nitrogen and phosphorus addition). Our results suggested that the response of phytoplankton to UVR depended largely on nutrient availability, which was embodied in the no significant responses of phytoplankton productivity and total biomass to UVR in the oligotrophic raw water from Lake Fuxian, but the positive responses of total biomass to UVR in the nutrient enrichment treatment. Furthermore, the response of phytoplankton to UVR was also taxa dependent. Chlorophytes and dinoflagellates showed positive response to UVR, whereas chrysophytes were quite sensitive to UVR; diatoms had no significant response to UVR under all nutrient conditions, while the response of cyanobacteria to UVR was highly dependent on nutrient status. This study highlights that the increase in nutrient concentrations in oligotrophic lake not only directly promotes the growth of phytoplankton but also combines with low UVR during summer to benefit the growth of eutrophic taxa based on the non-negative effect of UVR on total phytoplankton biomass and the positive effect on eutrophic taxa.

Fabrication of three-dimensional metal structures embedded in hydrogel by using femtosecond laser ablation and electroplating.

We demonstrated a method of fabricating three-dimensional (3D) metal structures in hydrogels with good conductivity by using femtosecond laser ablation and electroplating. The hydrogel containing Ag+ was first ablated by a femtosecond laser to form microchannels with an entrance achieving surface and then sandwiched between the anode and cathode to operate electroplating. Silver structures were formed along the microchannel from the microchannel entrance close to the cathode due to reduction of Ag+. The average resistivity of metal structures is measured to be about 4×10-7Ωm. A tetrahedron metallic microstructure embedded in hydrogel by this method was demonstrated to show its ability of 3D micromachining.

Enantioselective Reductive Coupling of Imines Templated by Chiral Diboron.

We herein report a general, practical, and highly efficient method for asymmetric synthesis of a wide range of chiral vicinal diamines via reductive coupling of imines templated by chiral diboron. The protocol features high enantioselectivity and stereospecificity, mild reaction conditions, simple operating procedures, use of readily available starting materials, and a broad substrate scope. The method signifies the generality of diboron-enabled [3,3]-sigmatropic rearrangement.

The pomegranate (Punica granatum L.) draft genome dissects genetic divergence between soft- and hard-seeded cultivars.

Complete and highly accurate reference genomes and gene annotations are indispensable for basic biological research and trait improvement of woody tree species. In this study, we integrated single-molecule sequencing and high-throughput chromosome conformation capture techniques to produce a high-quality and long-range contiguity chromosome-scale genome assembly of the soft-seeded pomegranate cultivar 'Tunisia'. The genome covers 320.31 Mb (scaffold N50 = 39.96 Mb; contig N50 = 4.49 Mb) and includes 33 594 protein-coding genes. We also resequenced 26 pomegranate varieties that varied regarding seed hardness. Comparative genomic analyses revealed many genetic differences between soft- and hard-seeded pomegranate varieties. A set of selective loci containing SUC8-like, SUC6, FoxO and MAPK were identified by the selective sweep analysis between hard- and soft-seeded populations. An exceptionally large selective region (26.2 Mb) was identified on chromosome 1. Our assembled pomegranate genome is more complete than other currently available genome assemblies. Our results indicate that genomic variations and selective genes may have contributed to the genetic divergence between soft- and hard-seeded pomegranate varieties.

Urgent retrograde two-stage hybrid repair of a complicated blunt traumatic aortic injury.

Blunt traumatic aortic injury (BTAI) is a rare but life-threatening emergency that is usually caused by sudden acceleration/deceleration injuries in vehicular accidents. We describe our initial experience of a retrograde two-stage hybrid treatment approach for the emergent management of a 63-year-old motorcyclist who presented with a complicated BTAI with malperfusion syndrome. To our best knowledge, this uncommon BTAI case with fatal distal malperfusion saved by an urgent retrograde two-stage hybrid procedure has been reported rarely. This early reperfusion strategy with two-stage retrograde endovascular technique could be an effective and life-saving treatment option for polytrauma patients with suitable aortic anatomy.

Synthesis and Enhanced Photocatalytic Activity of Porous SrTiO3/TiO2 Composites.

Porous photocatalysts have attracted significant attention for their large specific surface area, numerous surface catalytic active sites, and high photocatalytic activity. In this study, porous SrTiO3/TiO2 composites were successfully fabricated through a hydrothermal approach utilizing porous TiO2 as a substrate. The as-synthesized SrTiO3/TiO2 composites were then characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, Brunauer-Emmett-Teller (BET), and ultraviolet-visible spectroscopy (UV-Vis) analysis. The results of SEM and BET indicate that such composites have a porous structure and large surface area. Compared to unadulterated TiO2, SrTiO3 /TiO2 composites exhibit higher photocatalytic performance for the photodegradation of rhodamine B under UV-Vis irradiation. Additionally, it was found that when the content of SrTiO3 reaches 20%, it achieves the maximum photodegradation efficiency of 98.6% under UV-Vis irradiation over 60 min. These results demonstrate that SrTiO3/TiO2 composites are a promising material in terms of environmental cleanliness.

Seasonal and spatial distributions of euphotic zone and long-term variations in water transparency in a clear oligotrophic Lake Fuxian, China.

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth (Zeu) across the four seasons, and no significant correlations between Zeu and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Zeu in general. Nevertheless, significant differences in Zeu between the north region (NR) and the south region (SR) were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter (CDOM) in the NR due to runoff, especially in the rainy seasons (summer and autumn). CDOM and its terrigenous component had an important impact on Zeu in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years, with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants (CDOM and/or phytoplankton) are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.