1.Fibroblast Growth Factors in Parkinson’s Disease: Multi-target Neuroprotective Mechanisms Involving Neuroinflammation, Cellular Stress, and Ferroptosis
Hui WANG ; Zi-Gui ZHOU ; Teng-Teng HAN ; Chang-Zhi YANG ; Xue-Wen TIAN
Progress in Biochemistry and Biophysics 2026;53(4):855-874
Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the selective loss of dopaminergic neurons in the substantia nigra pars compacta and the pathological accumulation ofα‑synuclein. Although extensive progress has been made in elucidating its pathogenesis, current therapeutic approaches remain largely symptomatic, and effective disease-modifying treatments are still unavailable. Increasing evidence indicates that PD is driven by the interaction of multiple pathological processes, including neuroinflammation, iron homeostasis dysregulation and ferroptosis, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, oxidative stress, and impaired protein homeostasis, which together contribute to neuronal vulnerability and degeneration. Fibroblast growth factors (FGFs) comprise a family of 22 ligands that play important roles in neural development, stress responses, metabolic regulation, and the maintenance of nervous system homeostasis. Recent studies have shown that several FGF family members, such as FGF1, FGF2, FGF9, and FGF21, exert neuroprotective effects in cellular and animal models of PD. These effects include the regulation of inflammatory responses, oxidative stress, iron homeostasis, cellular stress adaptation, and neuronal survival. Compared with therapeutic strategies targeting a single pathogenic pathway, FGFs appear to influence multiple disease-related processes, suggesting their potential relevance to the complex pathophysiology of PD. Experimental evidence indicates that altered FGF signaling may contribute to dopaminergic neuron dysfunction through the coordinated regulation of several interconnected mechanisms. FGFs have been reported to modulate neuroinflammation by affecting the activation of microglia and astrocytes, thereby influencing the inflammatory environment in the central nervous system. In addition, FGFs are involved in the regulation of iron homeostasis and ferroptosis, partly through antioxidant signaling pathways associated with NRF2, SLC7A11, and GPX4. Moreover, FGFs can alleviate ER stress and mitochondrial dysfunction by activating intracellular signaling pathways such as PI3K/AKT, AMPK-PGC-1α, as well as SIRT1-dependent programs, which support cellular energy metabolism and redox balance. Recent advances in single-cell and spatial transcriptomic studies further suggest that FGF signaling is not limited to neuron-intrinsic mechanisms but also involves interactions among different glial cell types. Altered FGF ligand-receptor communication between astrocytes and oligodendrocytes has been observed in PD models and is associated with increased susceptibility of dopaminergic neurons to oxidative stress and ferroptosis. These findings indicate that the biological effects of FGFs are influenced by cell type and disease stage and may vary under different pathological conditions. In this review, we summarize recent progress in understanding the roles of FGF family members in PD, with a focus on their involvement in iron homeostasis dysregulation and ferroptosis, neuroinflammation, cellular stress responses, and neuronal protection and regeneration. By integrating current evidence, this review aims to provide a clearer understanding of how FGFs participate in PD pathogenesis and to offer a theoretical basis for future studies exploring their potential value in disease-modifying therapeutic strategies.
2.The Dual Role and Clinical Potential of Core Fucosylation in Liver Diseases
Zi-Han LEI ; Hui-Min XU ; De-Zhi ZHAO ; Yong-Hong GUO ; Hao-Qi DU
Progress in Biochemistry and Biophysics 2026;53(8):2161-2178
Core fucosylation, catalyzed exclusively by fucosyltransferase 8 (FUT8), is an evolutionarily conserved post-translational modification that has emerged as a central regulatory hub linking liver homeostasis, chronic disease progression, and malignant transformation. Liver diseases, particularly hepatocellular carcinoma, remain a leading global health burden characterized by late diagnosis, limited therapeutic options, and poor overall survival. While aberrant glycosylation is now recognized as a hallmark of cancer and inflammatory disorders, existing research on FUT8-mediated core fucosylation in liver diseases remains fragmented: the dynamic functional switch of FUT8 from a homeostatic regulator to a pathological driver across the full disease continuum has not been systematically delineated, and the integrated mechanisms by which core fucosylation modulates oncogenic signaling, metabolic reprogramming, and immune evasion remain poorly understood. This review synthesizes recent advances to establish a unified framework for understanding the dual role of core fucosylation in liver physiology and pathology, and evaluates its translational potential for precision medicine. At the molecular level, FUT8’s unique catalytic specificity makes core fucosylation an irreplaceable modification, as evidenced by the perinatal lethality and severe organ dysfunction in Fut8 knockout mice. In hepatocellular carcinoma, genomic amplification of guanosine 5'-diphosphate-fucose biosynthetic enzymes provides metabolic support for aberrant core fucosylation. FUT8 expression is tightly regulated by a multi-layered network: transcriptional activation via Wnt/β‑catenin and wild-type p53, epigenetic upregulation by lncRNAs, post-transcriptional repression by miR-122-5p and miR-34a, and virus-specific induction by hepatitis B virus/hepatitis C virus. Physiologically, core fucosylation maintains liver homeostasis through four core mechanisms: it acts as a molecular switch for epidermal growth factor receptor/hepatocyte growth factor receptor signaling to enable liver regeneration; directs polarized secretion of hepatocyte-derived glycoproteins into bile ducts; modulates cholesterol metabolism via the hepatocyte nuclear factor 1α-proprotein convertase subtilisin/kexin type 9-low density lipoprotein receptor axis; and regulates aging through insulin‑like growth factor 1 receptor signaling. Pathologically, core fucosylation exhibits context-dependent dual functions: in liver fibrosis, FUT8 upregulation in hepatic stellate cells forms a negative feedback loop that limits excessive fibrogenesis; in hepatocellular carcinoma, however, aberrant FUT8 overexpression drives cell-autonomous malignancy by constitutively activating epidermal growth factor/hepatocyte growth factor receptor, transforming growth factor‑β/Smad, and Wnt/β‑catenin pathways, while simultaneously establishing a multi-layered immune evasion network by stabilizing programmed cell death ligand 1 and cluster of differentiation 47, and impairing natural killer cell homeostasis via interleukin‑2 receptor β glycosylation. Clinically, stage-specific core fucosylation biomarkers enable non-invasive monitoring of liver disease progression: low molecular mass kringle-Fc fusion protein outperforms conventional markers for early fibrosis detection, while alpha-fetoprotein-L3 and novel glycopeptides (α‑2‑macroglobulin N‑linked glycosylation site 1424, lumican core fucosylated peptide) significantly improve early hepatocellular carcinoma diagnosis, especially in alpha-fetoprotein-negative patients. Next-generation detection technologies (chemoenzymatic labeling, site-specific mass spectrometry) overcome the specificity limitations of traditional lectin assays. Therapeutically, four promising strategies are emerging: small-molecule FUT8 inhibitors, afucosylated antibodies with enhanced antibody‑dependent cellular cytotoxicity, Fuc-modified targeted drug delivery systems, and core fucose-specific lectins for NASH treatment. The core challenge for clinical translation lies in FUT8’s inherent “double-edged sword” effect, as systemic inhibition disrupts its essential physiological functions beyond pathological roles. Long-term systemic FUT8 blockade not only impairs post-injury liver regeneration by abrogating epidermal growth factor/hepatocyte growth factor receptor signaling but also disrupts cholesterol homeostasis via the hepatocyte nuclear factor 1α-proprotein convertase subtilisin/kexin type 9-low density lipoprotein receptor axis, leading to dyslipidemia and altered bile secretion. Critically, it compromises immune surveillance by destabilizing interleukin‑2 receptor β on natural killer cells, reducing their cytotoxic activity against malignant and virally infected cells, and impairs IgG Fc-mediated effector functions, increasing susceptibility to infections. This fundamental trade-off between therapeutic efficacy and systemic toxicity necessitates a paradigm shift from non-specific global inhibition to precision modulation of pathological core fucosylation. By addressing these critical challenges, FUT8-mediated core fucosylation has the potential to transform liver disease management from late-stage intervention to early detection and precision therapy, ultimately improving patient outcomes and reducing the global burden of liver diseases.
3.Guidelines for the perioperative diagnosis and treatment of oncogene-driven non-small cell lung cancer (2026)
Weidong WANG ; Yongbin LIN ; Hui TIAN ; Gaofeng LI ; Shun XU ; Yongde LIAO ; Haitao MA ; Junfeng LIU ; Chundong GU ; Xiaolong YAN ; Shumin WANG ; Daqiang SUN ; Jianyang LIU ; Tao XUE ; Shaohua MA ; Zhigang LI ; Shuanghu YUAN ; Gen LIN ; Ling CAI ; Jianping ZHOU ; Wenzhao ZHONG ; Naixin LIANG ; Yi HAN ; Junfeng WANG ; Weidong ZHANG ; Xin WANG ; Lianjuan CHEN ; Lunxu LIU ; Xiuyi ZHI ; Lanjun ZHANG
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(09):1337-1353
Lung cancer constitutes the most prevalent and lethal malignant tumor in China. Approximately 85% of lung cancer diagnoses correspond to the non-small cell histological subtype [non-small cell lung cancer (NSCLC)]. Despite surgery being the mainstay for early-stage disease, postoperative recurrence remains high and adjuvant chemotherapy offers limited benefit. In recent years, targeted therapy has demonstrated substantial advantages in driver mutation-positive NSCLC. To this end, the Lung Cancer Medical Education Committee of the Chinese Medical Education Association developed guidelines based on a systematic review of evidence through November 2025, using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach and a modified Delphi method. Focusing on epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), and addressing ROS proto-oncogene 1 (ROS1), B-Raf proto-oncogene serine/threonine kinase (BRAF) V600E mutation, and mesenchymal-epithelial transition factor (MET) exon 14 (METex14) skipping, the guideline covers molecular testing, neoadjuvant/adjuvant therapy, perioperative strategies, minimal residual disease monitoring, and postoperative surveillance. It defines testing requirements, specifies stage-directed and subtype-specific treatments, and standardizes minimal residual disease monitoring. These recommendations emphasize precision and feasibility to improve survival and quality of life.
4.Mechanism of Ganoderma lucidum polysaccharides promoting myelin regeneration in demyelinated mice induced by cuprizone
Yan-qing LI ; Xiao-hui LI ; Qing WANG ; Li-juan SONG ; Li-zhi YANG ; Han-bin WANG ; Bao-guo XIAO ; Cun-gen MA
Chinese Pharmacological Bulletin 2025;41(7):1265-1273
Aim To explore the mechanism of Gano-derma lucidum polysaccharides(GLPS)promoting my-elin repair and regeneration in mice with chronic demy-elination induced by cuprizone(CPZ).Methods A total of 40 C57BL/6 mice were randomly divided into four groups:Normal+NS,Normal+GLPS,CPZ+NS and CPZ+GLPS.A chronic demyelination model was established using 0.2%CPZ.Open field and elevated plus maze tests were performed to observe the behavior-al changes in the mice.Immunofluorescence staining and Western blot were used to detect changes in myelin basic protein expression in the corpus callosum.ELISA was performed to measure the levels of TNF-α,IL-6,IL-1β and IL-10 in brain homogenates.Immunofluo-rescence staining was also used to observe the expres-sion of ionized calcium binding adapter molecule 1(Iba1)and neural-glial antigen 2(NG2).RT-qPCR and Western blot were conducted to assess the mRNA and protein expression levels of MBP,iNOS,COX-2,JAK2 and STAT3.Results Mice in the CPZ+NS group showed a significant decrease in body weight,cognitive behavior abnormalities,and impaired myelin regeneration.The expression of pro-inflammatory fac-tors increased,while anti-inflammatory factors de-creased.Additionally,Iba1 and NG2 expression in-creased,and the JAK2/STAT3 signaling pathway was activated.After GLPS intervention,the mouse body weight increased,myelin regeneration occurred,cogni-tive behavior was improved,the expression of inflamma-tory factors decreased,anti-inflammatory factors in-creased,NG2 expression was further elevated,and the proliferation of microglia as well as the activation of the JAK2/STAT3 signaling pathway was inhibited.Conclu-sions GLPS can improve cognitive behavior abnormali-ties and inflammatory responses in chronic demyelinated mice by inhibiting the JAK2/STAT3 signaling pathway,thereby promoting myelin repair and regeneration.
5.Application of a self-designed assistant device for distal osteotomy and reduction in ulnar impaction syndrome
Wei LI ; Mingtong HAN ; Gaofeng ZHANG ; Zhi ZHANG ; Hui XU ; Benlei WEI ; Cunmin RONG ; Bo ZHANG ; Qingluan HAN ; Qing CHANG
Chinese Journal of Orthopaedic Trauma 2025;27(5):451-456
Objective:To investigate the clinical efficacy of a self-designed assistant device for distal ulnar osteotomy and reduction in the surgical treatment of ulnar impaction syndrome.Methods:A retrospective analysis was performed to study the clinical data from the 27 patients with ulnar impaction syndrome who had been treated by distal ulnar shortening and fixation with 2 screws between January 2022 and August 2024 at Department of Hand and Foot Surgery,Affiliated Hospital of Jining Medical University. The cohort included 6 males and 21 females, with 13 left and 14 right sides affected and a mean age of (40.3±10.8) years (range: from 17 to 59 years). Based on their different assistant methods in osteotomy, the patients were divided into group A (15 cases) subjected to conventional freehand osteotomy and group B (12 cases) subjected to distal ulnar osteotomy and reduction assisted by our self-designed assistant device. Comparisons were made between the 2 groups regarding operative time, bone healing time, Mayo wrist function score at postoperative 16 weeks, number of the patients returning to their original occupations and complications.Results:There were no significant dif- ferences in the baseline characteristics between the 2 groups ( P>0.05). All patients were followed up postoperatively for (27.1±11.1) weeks (range: from 16 to 50 weeks). In group B, the operative time [50.0 (50.0, 62.5) min] and bone healing time [6.5 (6.0, 7.0) weeks] were significantly shorter than those in group A [80.0 (67.5, 92.5) min and 7.5 (6.8, 9.0) weeks] ( P<0.05). At postoperative 16 weeks, the Mayo wrist function score was 90.0 (85.0, 96.8) points for group A and 92.5 (85.0, 98.8) points for group B, showing no significant difference ( P>0.05). Five patients in group A and 4 ones in group B returned to their original work status, showing no significant difference either ( P>0.05). One case of non-union occurred in group A while no complication occurred in group B, demonstrating no significant difference either ( P>0.05). Conclusion:In the surgical treatment of ulnar impaction syndrome, compared with conventional freehand osteotomy, application of our self-designed assistant device for distal ulnar osteotomy and reduction is simple, less invasive, and comparable in functional recovery of the wrist, but superior in operative time and bone healing time.
6.A Novel Model of Traumatic Optic Neuropathy Under Direct Vision Through the Anterior Orbital Approach in Non-human Primates.
Zhi-Qiang XIAO ; Xiu HAN ; Xin REN ; Zeng-Qiang WANG ; Si-Qi CHEN ; Qiao-Feng ZHU ; Hai-Yang CHENG ; Yin-Tian LI ; Dan LIANG ; Xuan-Wei LIANG ; Ying XU ; Hui YANG
Neuroscience Bulletin 2025;41(5):911-916
7.Randomized, double-blind, parallel-controlled, multicenter, equivalence clinical trial of Jiuwei Xifeng Granules(Os Draconis replaced by Ostreae Concha) for treating tic disorder in children.
Qiu-Han CAI ; Cheng-Liang ZHONG ; Si-Yuan HU ; Xin-Min LI ; Zhi-Chun XU ; Hui CHEN ; Ying HUA ; Jun-Hong WANG ; Ji-Hong TANG ; Bing-Xiang MA ; Xiu-Xia WANG ; Ai-Zhen WANG ; Meng-Qing WANG ; Wei ZHANG ; Chun WANG ; Yi-Qun TENG ; Yi-Hui SHAN ; Sheng-Xuan GUO
China Journal of Chinese Materia Medica 2025;50(6):1699-1705
Jiuwei Xifeng Granules have become a Chinese patent medicine in the market. Because the formula contains Os Draconis, a top-level protected fossil of ancient organisms, the formula was to be improved by replacing Os Draconis with Ostreae Concha. To evaluate whether the improved formula has the same effectiveness and safety as the original formula, a randomized, double-blind, parallel-controlled, equivalence clinical trial was conducted. This study enrolled 288 tic disorder(TD) of children and assigned them into two groups in 1∶1. The treatment group and control group took the modified formula and original formula, respectively. The treatment lasted for 6 weeks, and follow-up visits were conducted at weeks 2, 4, and 6. The primary efficacy endpoint was the difference in Yale global tic severity scale(YGTSS)-total tic severity(TTS) score from baseline after 6 weeks of treatment. The results showed that after 6 weeks of treatment, the declines in YGTSS-TSS score showed no statistically significant difference between the two groups. The difference in YGTSS-TSS score(treatment group-control group) and the 95%CI of the full analysis set(FAS) were-0.17[-1.42, 1.08] and those of per-protocol set(PPS) were 0.29[-0.97, 1.56], which were within the equivalence boundary [-3, 3]. The equivalence test was therefore concluded. The two groups showed no significant differences in the secondary efficacy endpoints of effective rate for TD, total score and factor scores of YGTSS, clinical global impressions-severity(CGI-S) score, traditional Chinese medicine(TCM) response rate, or symptom disappearance rate, and thus a complete evidence chain with the primary outcome was formed. A total of 6 adverse reactions were reported, including 4(2.82%) cases in the treatment group and 2(1.41%) cases in the control group, which showed no statistically significant difference between the two groups. No serious suspected unexpected adverse reactions were reported, and no laboratory test results indicated serious clinically significant abnormalities. The results support the replacement of Os Draconis by Ostreae Concha in the original formula, and the efficacy and safety of the modified formula are consistent with those of the original formula.
Adolescent
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Child
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Child, Preschool
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Female
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Humans
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Male
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Double-Blind Method
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Drugs, Chinese Herbal/therapeutic use*
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Tic Disorders/drug therapy*
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Treatment Outcome
8.Identification of critical quality attributes related to property and flavor of Jianwei Xiaoshi Tablets based on T1R2/T1R3/TRPV1-HEMT biosensor.
Dong-Hong LIU ; Yan-Yu HAN ; Jing WANG ; Hai-Yang LI ; Xin-Yu GUO ; Hui-Min FENG ; Han HE ; Shuo-Shuo XU ; Zhi-Jian ZHONG ; Zhi-Sheng WU
China Journal of Chinese Materia Medica 2025;50(14):3930-3937
The quality of traditional Chinese medicine(TCM) is a critical foundation for ensuring the stability of its efficacy, as well as the safety and effectiveness of its clinical use. The identification of critical quality attributes(CQAs) is one of the core components of TCM preparation quality control. This study focuses on Jianwei Xiaoshi Tablets and explores their CQAs related to property and flavor from the perspective of taste receptor proteins. Three taste receptor proteins, T1R2, T1R3, and TRPV1, were selected, and a biosensor based on high-electron-mobility transistor(HEMT) was constructed to detect the interactions between Jianwei Xiaoshi Tablets and taste receptor proteins. Simultaneously, liquid chromatography-mass spectrometry(LC-MS) technology was used to analyze the chemical composition of Jianwei Xiaoshi Tablets. In examining the interaction strength, the results indicated that the interaction between Jianwei Xiaoshi Tablets and TRPV1 protein was the strongest, followed by T1R3, with the interaction with T1R2 being relatively weaker. By combining biosensing technology with LC-MS, 16 chemical components were identified from Jianwei Xiaoshi Tablets, among which six were selected as CQAs for sweetness and seven for pungency. Further validation experiments demonstrated that CQAs such as hesperidin and hesperetin had strong interactions with their corresponding taste receptor proteins. Through the combined use of multiple technological approaches, this study successfully determined the property and flavor-related CQAs of Jianwei Xiaoshi Tablets. It provides novel ideas and approach for the identification of CQAs in TCM preparations and offers comprehensive theoretical support for TCM quality control, contributing to the improvement and development of TCM preparation quality control systems.
Drugs, Chinese Herbal/chemistry*
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Biosensing Techniques/methods*
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TRPV Cation Channels/chemistry*
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Tablets/chemistry*
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Receptors, G-Protein-Coupled/genetics*
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Quality Control
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Taste
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Humans
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Mass Spectrometry
9.Curcumin improving behavioral deficits in Parkinson's disease mice via modulation of gut microbiota
Wen-Hui LI ; Zhi-Hong ZHAO ; Li-Juan WANG ; Jin-Jing HE ; Yu-Ting LIU ; Qiu-Qin HAN
Acta Anatomica Sinica 2025;56(2):143-149
Objective To explore the mechanism by which curcumin improves behavioral deficits in mice with Parkinson's disease(PD)through fecal microbiota transplantation.Methods A subacute model of PD in mice was induced by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP).Fecal microbiota from both the model group and the curcumin(Cur)-treated group(80 m g/kg)were collected and analyzed.The experiment involving fecal microbiota transplantation was structured into four distinct groups,fecal microbiota solvent transplantation group(FMTcon),model fecal microbiota transplantation group(FMTmodel),MPTP-induced model group(model),and model group subjected to fecal microbiota transplantation following curcumin treatment(model+FMTCur).The motor skills of the mice were assessed by using rod rotation,pole climbing experiment,and open field tests.Immunofluorescence techniques were employed to observe the expression tyrosine hydroxylase(TH)-positive neurons in the substantia nigra of the brain.Additionally,the gene expression of tumor necrosis factor-α(TNF-α)in the midbrain of mice was analyzed,alongside the protein expression of nuclear factor-κB(NF-κB)and nucleotide binding oligomerization domain-like receptor protein 3(NLRP3).Results The subacute PD animal model in mice was successfully established,and fecal microbiota were separated and gathered.The model group exhibited significant motor impairment,as evidenced by a shortened rod rotation time(P<0.05),prolonged pole climbing time(P<0.05),significantly reduced total movement distance within the open field(P<0.001),and decreased time spent in the central zone(P<0.01).The relative expression level of TH+neurons in the substantia nigra was significantly reduced(P<0.01).Moreover,mRNA expression of TNF-α in the midbrain increased significantly(P<0.01),along with significant elevations in protein expression of NF-κB(P<0.001),phosphorylated NF-κB(p-NF-κB)(P<0.01),NLRP3(P<0.001),and Caspase-1(P<0.01).The transplanted model microbial group(FMTmodel)also exhibited motor impairment,manifested by a trend of shortened rod rotation time,prolonged pole climbing time,a significant decrease in total movement distance within the open field(P<0.01),and a trend of shortened time spent in the central zone.The relative expression level of TH+neurons in the substantia nigra decreased significantly(P<0.05).Additionally,mRNA expression of TNF-α in the midbrain increased significantly(P<0.01),along with notable elevations in the protein expression of NF-κB(P<0.05),and Caspase-1(P<0.01).Treatment with curcumin in the fecal microbiota transplantation group of mice(model+FMTCur)showed improvements in motor abilities,evidenced by shortened pole climbing time(P<0.05),significantly prolonged rod rotation time(P<0.01),and extended time spent in the central zone(P<0.05).The relative expression level of TH+dopaminergic neurons in the substantia nigra increased significantly(P<0.05).Moreover,mRNA expression of TNF-α in the midbrain decreased significantly(P<0.01),along with notable reductions in the protein expression of NF-κB(P<0.001),p-NF-κB(P<0.01),NLRP3(P<0.05),and Caspase-1(P<0.01).Conclusion Fecal microbiota transplantation in PD model mice can induce behavioral deficits,damage TH+neurons in the substantia nigra,and trigger neuroinflammation in the brain.Subsequent curcumin treatment can ameliorate these deficits,reverse damage to TH+neurons,reduce neuroinflammatory factors,and decrease the expression of NF-κB and NLRP3 pathways.This preliminary evidence suggests that curcumin may improve Parkinsonian behavioral deficits in mice by modulating the gut microbiota.
10.The Invariant Neural Representation of Neurons in Pigeon’s Ventrolateral Mesopallium to Stereoscopic Shadow Shapes
Xiao-Ke NIU ; Meng-Bo ZHANG ; Yan-Yan PENG ; Yong-Hao HAN ; Qing-Yu WANG ; Yi-Xin DENG ; Zhi-Hui LI
Progress in Biochemistry and Biophysics 2025;52(10):2614-2626
ObjectiveIn nature, objects cast shadows due to illumination, forming the basis for stereoscopic perception. Birds need to adapt to changes in lighting (meaning they can recognize stereoscopic shapes even when shadows look different) to accurately perceive different three-dimensional forms. However, how neurons in the key visual brain area in birds handle these lighting changes remains largely unreported. In this study, pigeons (Columba livia) were used as subjects to investigate how neurons in pigeon’s ventrolateral mesopallium (MVL) represent stereoscopic shapes consistently, regardless of changes in lighting. MethodsVisual cognitive training combined with neuronal recording was employed. Pigeons were first trained to discriminate different stereoscopic shapes (concave/convex). We then tested whether and how light luminance angle and surface appearance of the stereoscopic shapes affect their recognition accuracy, and further verify whether the results rely on specify luminance color. Simultaneously, neuronal firing activity of neurons was recorded with multiple electrode array implanted from the MVL during the presentation of difference shapes. The response was finally analyzed how selectively they responded to different stereoscopic shapes and whether their selectivity was affected by the changes of luminance condition (like lighting angle) or surface look. Support vector machine (SVM) models were trained on neuronal population responses recorded under one condition (light luminance angle of 45°) and used to decode responses under other conditions (light luminance angle of 135°, 225°, 315°) to verify the invariance of responses to different luminance conditions. ResultsBehavioral results from 6 pigeons consistently showed that the pigeons could reliably identify the core 3D shape (over 80% accuracy), and this ability wasn’t affected by changes in light angle or surface appearance. Statistical analysis of 88 recorded neurons from 6 pigeons revealed that 83% (73/88) showed strong selectivity for specific 3D shapes (selectivity index>0.3), and responses to convex shapes were consistently stronger than to concave shapes. These shape-selective responses remained stable across changes in light angle and surface appearance. Neural patterns were consistent under both blue and orange lighting. The decoding accuracy achieves above 70%, suggesting stable responses under different conditions (e.g., different lighting angles or surface appearance). ConclusionNeurons in the pigeon MVL maintain a consistent neural encoding pattern for different stereoscopic shapes, unaffected by illumination or surface appearance. This ensures stable object recognition by pigeons in changing visual environments. Our findings provide new physiological evidence for understanding how birds achieve stable perception (“invariant neural representations”) while coping with variations in the visual field.

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