👤 Yan Pi

Atherosclerotic lesions are the fundamental pathologies of cardiovascular diseases. The exact role of the nuclear factor erythroid 2-related factor 2 (NRF2) in macrophages in atherosclerosis remains uncertain. This study aimed to investigate the role of NRF2 in myeloid cells in the development of atherosclerosis. Single-cell RNA sequencing databases were used to explore the expression levels of NRF2 in human and murine atherosclerosis. Plaque areas, necrotic core size, instability index, and efferocytosis in aortic lesions were investigated in myeloid cell-specific Nrf2-knockout mice on an ApoE-deficient background (Nrf2(M)-KO; ApoE NRF2 expression was upregulated in the macrophages of human and murine atherosclerotic arteries compared with their corresponding controls. Nrf2(M)-KO; ApoE Myeloid-specific deletion of Nrf2 promotes inflammation and inhibits macrophage efferocytosis, thereby leading to the aggravation of atherosclerosis. NRF2 activation in macrophages could be a valuable strategy for preventing and treating atherosclerosis. Show less

This is a cross-sectional study designed to identify the latent profiles of psychological resilience in elderly patients with fracture and examine the relationship between resilience categories and fear of falling (FOF), thereby informing individualized rehabilitation strategies. A convenience sample was drawn from elderly patients admitted to the Department of Traumatology and Orthopedics at a tertiary general hospital in Beijing between September 2024 and July 2025 due to fall-related fractures. A total of 213 older adults aged 60 and above with fall-related fractures were included. Psychological resilience was assessed using the Connor-Davidson Resilience Scale (CD-RISC), and FOF was measured with the Falls Efficacy Scale-International (FES-I). Latent Profile Analysis (LPA) was used to identify resilience profiles. Logistic and linear regression analyses, adjusting for age, sex, comorbidities, pain level, functional status, and time since fracture/surgery, were performed to explore the relationship between resilience subtypes (entered as a continuous CD-RISC score), demographic and clinical factors, and FOF levels. The age of elderly patients with fall-related fractures was 60–98 (75.28 ± 8.73) years old, and the median age was 74 years old. Three latent resilience profiles were identified: low (33.5%), moderate (22.7%), and high (43.8%) resilience groups. Patients in the high-resilience group exhibited significantly lower FOF scores than those in the other two groups ( Psychological resilience is independently associated with fear of falling among elderly fracture patients, with a clear gradient across resilience profiles. Enhancing resilience, particularly in low-resilience individuals, may be a potential target for intervention, though causal inference is limited by the cross-sectional design and single-center, convenience sampling strategy. Integrating resilience assessment into clinical evaluation could support more holistic rehabilitation planning. ChiCTR2400089221, September 4, 2024. Show less

Chondrocytes store lipids in the form of lipid droplets (LDs) and maintain cartilage lipid metabolic homeostasis by consuming or regenerating LDs. This modulation is largely mediated by a series of biochemical factors. Fibroblast growth factor 8 (FGF8) is one of the most important factors involved in the proliferation, differentiation, and migration of chondrocytes and has attracted increasing attention in the physiology and pathology of cartilage. However, the effect of FGF8 on LD accumulation in chondrocytes remains unclear. This study aims to elucidate the role of FGF8 in LDs and explore the underlying biomechanism involved. The results reveal that FGF8 promotes LD accumulation in chondrocytes by upregulating perilipin1 (Plin1) expression. FGF8 activates the cytoplasmic p-p38 signaling pathway via fibroblast growth factor receptor 1 (FGFR1) to increase LD accumulation in chondrocytes. Subsequent experiments with siRNAs and specific inhibitors further confirm the importance of the FGFR1/p38 axis for LD accumulation in chondrocytes exposed to FGF8. The results increase our understanding of the role of FGF8 in the lipid metabolic homeostasis of chondrocytes and provide insights into the physiology and pathology of cartilage. Show less

Lupus nephritis (LN) refers to the injury caused by systemic lupus erythematosus (SLE) involving the kidneys. A previous study identified angiopoietin-like protein 4 (ANGPTL4) as a novel urinary biomarker for tracking disease activity in LN. To investigate the detailed role and regulatory mechanism of ANGPTL4 in experimental models of LN. MRL/lpr mice 11-week-old were injected with adeno-associated virus (AAV)-mediated ANGPTL4 short hairpin RNA (shRNA). At 16 and 20 weeks of age, 24-h urine samples were harvested to measure proteinuria levels. After the mice were sacrificed, blood and kidney tissues were harvested to examine serum creatinine (cr) and blood urea nitrogen (BUN) levels, kidney histological changes, and pro-inflammatory cytokine production. Additionally, the levels of NLRP3 inflammasome-associated molecules in mouse renal tissues were detected to clarify the underlying mechanism. The AAV-sh-ANGPTL4 injection significantly reduced the proteinuria, cr, and BUN levels in MRL/lpr mice. ANGPTL4 silencing ameliorated glomerular, tubular, and interstitial damage in mice, mitigating the pathological alternations of LN. In addition, ANGPTL4 knockdown repressed pro-inflammatory cytokine production in the kidneys. Mechanically, ANGPTL4 suppression inhibited NLRP3 inflammasome expression in renal tissues of mice. ANGPTL4 silencing inhibits the NLRP3 inflammasome-mediated inflammatory response, thereby ameliorating LN in MRL/lpr mice. Show less

The melanocortin receptors are defined as a series of vital pharmaceutical targets to regulate neuronal appetite and maintain controllable body weight for mammals and teleosts. Melanocortin receptor accessory protein 2 (MRAP2) functions as an essential accessory player that modulates the surface translocation and binding to a variety of endogenous or synthetic hormones of central melanocortin-4 receptor (MC4R) signaling. MRAP2 is a single-transmembrane protein and could form a functional symmetric antiparallel homodimer topology. Here, we inverted the N-terminal, transmembrane, and C-terminal domains and generated six distinct conformational variants of the mouse MRAP2 to explore the functional orientations and the internal symmetry of MRAP2 dimers. These remolded MRAP2 mutants showed proper assembly of the antiparallel homodimer and binding to the MC4R, but slightly altered the regulatory profile on the surface expression and the ligand-stimulated cAMP cascades of MC4R. This study elucidated the importance of the orientation of each domain of the single-transmembrane protein and revealed the pharmacological properties of the internal symmetry of the antiparallel homodimer for MRAP2. Show less

How animals, particularly livestock, adapt to various climates and environments over short evolutionary time is of fundamental biological interest. Further, understanding the genetic mechanisms of adaptation in indigenous livestock populations is important for designing appropriate breeding programs to cope with the impacts of changing climate. Here, we conducted a comprehensive genomic analysis of diversity, interspecies introgression, and climate-mediated selective signatures in a global sample of sheep and their wild relatives. By examining 600K and 50K genome-wide single nucleotide polymorphism data from 3,447 samples representing 111 domestic sheep populations and 403 samples from all their seven wild relatives (argali, Asiatic mouflon, European mouflon, urial, snow sheep, bighorn, and thinhorn sheep), coupled with 88 whole-genome sequences, we detected clear signals of common introgression from wild relatives into sympatric domestic populations, thereby increasing their genomic diversities. The introgressions provided beneficial genetic variants in native populations, which were significantly associated with local climatic adaptation. We observed common introgression signals of alleles in olfactory-related genes (e.g., ADCY3 and TRPV1) and the PADI gene family including in particular PADI2, which is associated with antibacterial innate immunity. Further analyses of whole-genome sequences showed that the introgressed alleles in a specific region of PADI2 (chr2: 248,302,667-248,306,614) correlate with resistance to pneumonia. We conclude that wild introgression enhanced climatic adaptation and resistance to pneumonia in sheep. This has enabled them to adapt to varying climatic and environmental conditions after domestication. Show less

Trimethyltin chloride (TMT) is widely used as a constituent of fungicides and plastic stabilizers in the industrial and agricultural fields, and is generally acknowledged to have potent neurotoxicity, especially in the hippocampus; however, the mechanism of induction of neurotoxicity by TMT remains elusive. Herein, we exposed Neuro-2a cells to different concentrations of TMT (2, 4, and 8 μM) for 24 h. Proteomic analysis, coupled with bioinformatics analysis, revealed the important role of macroautophagy/autophagy-lysosome machinery in TMT-induced neurotoxicity. Further analysis indicated significant impairment of autophagic flux by TMT via suppressed lysosomal function, such as by inhibiting lysosomal proteolysis and changing the lysosomal pH, thereby contributing to defects in autophagic clearance and subsequently leading to nerve cell death. Mechanistically, molecular interaction networks of Ingenuity Pathway Analysis identified a downregulated molecule, KIF5A (kinesin family member 5A), as a key target in TMT-impaired autophagic flux. TMT decreased KIF5A protein expression, disrupted the interaction between KIF5A and lysosome, and impaired lysosomal axonal transport. Moreover, Show less

Melanocortin-3 receptor (MC3R), melanocortin-4 receptor (MC4R), and a recently identified melanocortin-2 receptor accessory protein 2 (MRAP2), are highly expressed in hypothalamus and coordinately regulate energy homeostasis, but the single cellular transcriptome of melanocortin system remains unknown. Several infrequent MRAP2 variants are reported from severe obese human patients but the mechanisms on how they affect melanocortin signaling are unclear. First, we performed in silico analysis of mouse hypothalamus RNA sequencing datasets at single-cell resolution from two independent studies. Next, we inspected the three-dimensional conformational alteration of three mutations on MRAP2 protein. Finally, the influence of MRAP2 variants on MC3R and MC4R signaling was analyzed in vitro. (1) We confirmed the actual co-expression of Mrap2 with Mc3r and Mc4r, and demonstrated more broad distribution of Mrap2-positive neuronal populations than Mc3r or Mc4r in mouse hypothalamus. (2) Compared with wild-type MRAP2, MRAP2 This is the first dedicated description of single-cell transcriptome signature of Mrap2, Mc3r, and Mc4r in the central nerve system and the first evidence describing the unique dimer formation, conformational change, and pharmacological effect of MRAP2 mutations on MC3R signaling. Show less

The association between polymorphism -1131T/C in the promoter region of apolipoprotein A5 (APOA5) and ischemic stroke and plasma triglyceride (TG) levels remains controversial. To better clarify the association between APOA5-1131T/C and risk of ischemic stroke and plasma TG levels, we performed a meta-analysis to examine the allele and genotype of APOA5-1131T/C polymorphism in ischemic stroke cases and controls. Based on the search of PubMed, Embase, MEDLINE, CNKI (National Knowledge Infrastructure) and CBM (Chinese BioMedical Literature Database) databases, we identified and abstracted outcome data from all articles to evaluate the association between APOA5 and ischemic stroke/plasma TG levels. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were performed in dominant model (CC + TC vs. TT), recessive model (CC vs. TC + TT), homozygote comparison (CC vs. TT) and heterozygote comparison (TC vs. TT). The association between dominant model (CC + TC vs. TT) and plasma TG/total cholesterol/high-density lipoprotein cholesterol levels was measured by a weighted mean difference (WMD) with its corresponding 95% CI. To evaluate the ethnicity-specific effects, subgroup analyses were performed by ethnic group. A meta-analysis containing 2,294 ischemic stroke cases and 1,858 controls from 8 case-control studies was performed. The results showed that APOA5-1131T/C polymorphism was significantly associated with ischemic stroke in all comparison models (CC + TC vs. TT, OR = 1.70, 95% CI = 1.24-2.32; CC vs. TC + TT, OR = 1.36, 95% CI = 0.98-1.90; CC vs. TT, OR = 1.73, 95% CI = 1.34-2.23; TC vs. TT, OR = 1.67, 95% CI = 1.19-2.36). On subgroup analysis by ethnicity, similarly significant associations were found in both Asians and Europeans, and the Europeans possessed a higher risk of ischemic stroke, especially in CC versus TT model (OR = 4.47, 95% CI = 1.33-15.06). Significant association between the C allele and elevated TG levels was detected in both ischemic stroke cases and controls; the TG levels were higher in the ischemic stroke cases and controls carrying the APOA5-1131C allele than in the noncarriers (CC + TC vs. TT, cases WMD = 0.43, 95% CI = 0.27-0.59; controls WMD = 0.51, 95% CI = 0.35-0.66). Similar within-group comparison of the total cholesterol and high-density lipoprotein cholesterol levels did not show any difference. Our meta-analysis revealed that the APOA5-1131T/C polymorphism is associated with a significant risk of ischemic stroke and elevated TG levels. The CC genotype and C allele might be a genetic risk factor that increases susceptibility of ischemic stroke and elevates plasma TG levels, and might be a useful target for clinical therapeutic intervention. Show less