Melatonin Alleviates Osteoarthritis by Regulating NADPH Oxidase 4-Induced Ferroptosis and Mitigating Mitochondrial Dysfunction.

Recent evidence indicates that the damaged regions in osteoarthritis are accompanied by the accumulation of iron ions. Ferroptosis, as an iron-dependent form of cell death, holds significant implications in osteoarthritis. Melatonin, a natural product with strong scavenging abilities against reactive oxygen species and lipid peroxidation, plays a crucial role in the treatment of osteoarthritis. This study aims to demonstrate the existence of ferroptosis in osteoarthritis and explore the specific mechanism of melatonin in suppressing ferroptosis and alleviating osteoarthritis. Our findings reveal that melatonin reverses inflammation-induced oxidative stress and lipid peroxidation while promoting the expression of extracellular matrix components in chondrocytes, safeguarding the cells. Our research has revealed that NADPH oxidase 4 (NOX4) serves as a crucial molecule in the ferroptosis process of osteoarthritis. Specifically, NOX4 is located on mitochondria in chondrocytes, which can induce disorders in mitochondrial energy metabolism and dysfunction, thereby intensifying oxidative stress and lipid peroxidation. LC-MS analysis further uncovered that GRP78 is a downstream binding protein of NOX4. NOX4 induces ferroptosis by weakening GRP78's protective effect on GPX4 and reducing its expression. Melatonin can inhibit the upregulation of NOX4 on mitochondria and mitigate mitochondrial dysfunction, effectively suppressing ferroptosis and alleviating osteoarthritis. This suggests that melatonin therapy represents a promising new approach for the treatment of osteoarthritis.

Case report: Levodopa challenge test is important in identifying dopamine-induced freezing of gait in patient with Parkinson's disease.

Introduction: Freezing of gait (FOG) is a disabling and heterogeneous symptom in patients with Parkinson's disease (PD). Among them, dopamine-induced FOG is rare and difficult to identify. The treatment of dopamine-induced FOG is complex. Case presentation: We herein presented a case of PD patient who complicated with refractory FOG. It was identified as dopamine-induced FOG during levodopa challenge test. Her symptoms were alleviated after we reduced the total equivalent dosage of levodopa. Conclusion: Our report emphasizes the importance of levodopa challenge test in identifying different types of FOG, which is very important for further adjusting treatment.

Causal relationship between OHSS and immune cells: A Mendelian randomization study.

OBJECTIVE: To confirm the causal relationship between immune cells and Ovarian Hyperstimulation Syndrome. DESIGN: Obtaining data, collecting single nucleotide polymorphisms, detecting instrumental variables heterogeneity, assessing causality, and assessing bidirectional causality. SUBJECTS: A two sample Mendelian study to confirm the causal relationship between immune cells and Ovarian Hyperstimulation Syndrome. EXPOSURE: Immune cell phenotype (including 22 million SNPs from GWAS on 3757 European individuals). MAIN OUTCOME MEASURES: Inverse variance weighting, one-sample analysis, MR-Egger, weighted median and weighted mode are used to assess the causal relationship between 731 immunophenotypes and Ovarian Hyperstimulation Syndrome. The weighted median and Mendelian Randomization multi-effect residuals and Mendelian Randomization multi-effect residuals and outlier tests are used to assess bidirectional causality between this two. RESULTS: After False Discovery Rate correction, 9 immunophenotypes were found to be significantly associated with the risk of Ovarian Hyperstimulation Syndrome. B cell panel: IgD+ AC (OR, 0.90) 、CD19 on CD24+ CD27+ (OR, 0.86) 、BAFF-R on CD20- CD38 (OR, -1.22); Mature T cell group panel: EM DN (CD4 -CD8-) AC (OR, 1.46); Myeloid cell panel: Mo MDSC AC (OR, 1.13) 、CD45 on CD33br HLA-DR+ (OR, 0.87); Monocyte panel: HLA-DR on monocyte (OR, 0.86) 、CCR2 on CD14+ CD16+ monocyte (OR, 1.15) 、cDC panel: HLA-DR on myeloid DC (OR, 0.89). CONCLUSION: This study shows the potential link between OHSS and immune cells by genetic means, providing new ideas for future clinical and basic research.

CST3 alleviates retinal vascular leakage by regulating the Rap1 signaling pathway.

Retinal vascular leakage is a major event in several retinal diseases, including diabetic retinopathy (DR). In a previous study, we demonstrated that the aqueous humor concentration of Cystatin C (CST3), a physiological inhibitor of cysteine protease, is negatively correlated with the severity of diabetic macular edema. However, its function in the retina has not been clearly elucidated. In this study, we found a significant decrease in the aqueous humor concentration of CST3 with DR progression. Furthermore, we found that CST3 was expressed in retinal endothelial cells and that its expression was significantly downregulated in high glucose-treated human retinal microvascular endothelial cells (HRMECs) and the retinal vessels of oxygen-induced retinopathy (OIR) mice. Silencing CST3 expression resulted in decreased HRMEC migration and tubule formation ability. Exogenous addition of the CST3 protein significantly improved HRMEC migration and tubular formation. In-vivo experiments demonstrated that CST3 silencing induced retinal vascular leakage in WT mice, while its intravitreal injection significantly reduced retinal leakage in OIR mice. Mechanistically, CST3 promoted the expression of the downstream adhesion molecules, claudin5, VE-cadherin, and ZO-1, in retinal vascular cells by regulating the Rap1 signaling pathway. Therefore, this study revealed a novel mechanism by which CST3 improves retinal vascular function and provided evidence that it is a potential therapeutic target for retinal vascular leakage.

The de novo missense mutation F224S in GABRB2, identified in epileptic encephalopathy and developmental delay, impairs GABAAR function.

Genetic variants in genes encoding subunits of the γ-aminobutyric acid-A receptor (GABAAR) have been found to cause neurodevelopmental disorders and epileptic encephalopathy. In a patient with epilepsy and developmental delay, a de novo heterozygous missense mutation c.671 T > C (p.F224S) was discovered in the GABRB2 gene, which encodes the ß2 subunit of GABAAR. Based on previous studies on GABRB2 variants, this new GABRB2 variant (F224S) would be pathogenic. To confirm and investigate the effects of this GABRB2 mutation on GABAAR channel function, we conducted transient expression experiments using GABAAR subunits in HEK293T cells. The GABAARs containing mutant ß2 (F224S) subunit showed poor trafficking to the cell membrane, while the expression and distribution of the normal α1 and γ2 subunits were unaffected. Furthermore, the peak current amplitude of the GABAAR containing the ß2 (F224S) subunit was significantly smaller compared to the wild type GABAAR. We propose that GABRB2 variant F224S is pathogenic and GABAARs containing this ß2 mutant reduce response to GABA under physiological conditions, which could potentially disrupt the excitation/inhibition balance in the brain, leading to epilepsy.

Liver injury protection of Artemisia stechmanniana besser through PI3K/AKT pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia stechmanniana Besser, one of the most prevalent botanical medicines in Chinese, has been traditionally used for hepatitis treatment. However, the bioactive components and pharmacological mechanism on alcohol-induced liver injury remains unclear. AIM OF THE STUDY: To investigate the effect of A. stechmanniana on alcohol-induced liver damage, and further explore its mechanism. MATERIALS AND METHODS: Phytochemical isolation and structural identification were used to determine the chemical constituents of A. stechmanniana. Then, the alcohol-induced liver damage animal and cell model were established to evaluate its hepato-protective potential. Network pharmacology, molecular docking and bioinformatics were integrated to explore the mechanism and then the prediction was further supported by experiments. Moreover, both compounds were subjected to ADMET prediction through relevant databases. RESULTS: 28 compounds were isolated from the most bioactive fraction, ethyl acetate extract A. stechmanniana, in which five compounds (abietic acid, oplopanone, oplodiol, hydroxydavanone, linoleic acid) could attenuate mice livers damage caused by alcohol intragastration, reduce the degree of oxidative stress, and serum AST and ALT, respectively. Furthermore, abietic acid and hydroxydavanone exhibited best protective effect against alcohol-stimulated L-O2 cells injury among five bioactive compounds. Network pharmacology and bioinformatics analysis suggested that abietic acid and hydroxydavanone exhibiting drug likeliness characteristics, were the principal active compounds acting on liver injury treatment, primarily impacting to cell proliferation, oxidative stress and inflammation-related PI3K-AKT signaling pathways. Both of them displayed strong binding energies with five target proteins (HRAS, HSP90AA1, AKT1, CDK2, NF-κB p65) via molecular docking. Western blotting results further supported the predication with up-regulation of protein expressions of CDK2, and down-regulation of HRAS, HSP90AA1, AKT1, NF-κB p65 by abietic acid and hydroxydavanone. CONCLUSION: Alcohol-induced liver injury protection by A. stechmanniana was verified in vivo and in vitro expanded its traditional use, and its two major bioactive compounds, abietic acid and hydroxydavanone exerted hepatoprotective effect through the regulation of PI3K-AKT signaling pathway.

Generation of xanthohumol derivatives through fungi-mediated biotransformation.

Xanthohumol (XTH, 1), a major prenylated chalcone in hops, has attracted considerable interests because of its pharmaceutical potency. To explore more related derivatives of XTH, its biotransformation was performed using the in vitro microbial model. Fungus Mucor sp. exhibited a robust biocatalytic feature to transform the substrate. Preparative fungi-mediated biotransformation led to the isolation of two new (2 and 5) and eight known (3, 4 and 6-11) metabolites. The two new metabolites were identified as (2″R)-dihydroxanthohumol B (2) and xanthohumol L 4'-O-ß-D-glucopyranoside (5) based on the combined spectroscopic analysis. According to the cytotoxic activities of all metabolites, compounds 7 and 9 showed relatively sensitive cytotoxic activity against A375 and A549 cancer cell lines, respectively. These findings not only provided a biological approach to achieve the derivatives of XTH but also gave an information for the lead optimisation of XTH for the development of potential anti-cancer agents.

Association analyses of apolipoprotein E genotypes and cognitive performance in patients with Parkinson's disease.

BACKGROUND: Cognitive impairment is a common non-motor symptom of Parkinson's disease (PD). The apolipoprotein E (APOE) ε4 genotype increases the risk of Alzheimer's disease (AD). However, the effect of APOEε4 on cognitive function of PD patients remains unclear. In this study, we aimed to understand whether and how carrying APOEε4 affects cognitive performance in patients with early-stage and advanced PD. METHODS: A total of 119 Chinese early-stage PD patients were recruited. Movement Disorder Society Unified Parkinson's Disease Rating Scale, Hamilton anxiety scale, Hamilton depression scale, non-motor symptoms scale, Mini-mental State Examination, Montreal Cognitive Assessment, and Fazekas scale were evaluated. APOE genotypes were determined by polymerase chain reactions and direct sequencing. Demographic and clinical information of 521 early-stage and 262 advanced PD patients were obtained from Parkinson's Progression Marker Initiative (PPMI). RESULTS: No significant difference in cognitive performance was found between ApoEε4 carriers and non-carriers in early-stage PD patients from our cohort and PPMI. The cerebrospinal fluid (CSF) Amyloid Beta 42 (Aß42) level was significantly lower in ApoEε4 carrier than non-carriers in early-stage PD patients from PPMI. In advanced PD patients from PPMI, the BJLOT, HVLT retention and SDMT scores seem to be lower in ApoEε4 carriers without reach the statistical significance. CONCLUSIONS: APOEε4 carriage does not affect the cognitive performance of early-stage PD patients. However, it may promote the decline of CSF Aß42 level and the associated amyloidopathy, which is likely to further contribute to the cognitive dysfunction of PD patients in the advanced stage.

Microwave ablation with hydrodissection used for the treatment of vascular malformations: effectiveness and safety study.

Object: The aim of the study was to investigate the safety, effectiveness, and peripheral nerve protection in ultrasound-guided microwave ablation (US-guided-MWA) for vascular malformations (VMs) closely related to peripheral nerve. Materials and methods: From August 2019 to February 2022, 31 patients with 39 VMs received US-guided-MWA. All lesions were confirmed to be closely related to the peripheral nerve by imaging evaluation. Hydrodissection was applied to protect surrounding normal tissue, including peripheral nerves. The patients were followed up at 1day, 2 days, 3 days, 1 week, 1 month, 3 months after operation. Measurements of lesion volume, volume reduction ratio (VRR), sensory and functional abnormalities of adjacent nerves, number of treatments, complication details, personal satisfaction, recurrence, and symptom improvement were recorded. Results: Among the 39 VMs, the maximum volume is 128.58ml, while the minimum volume is 0.99ml. After a mean follow-up of 13.06 ± 4.83 months, the mean numerical rating scale (NRS) score decreased from 5.13 ± 1.65 to 0.53 ± 0.83 (P<0.0001). The mean mass volume was reduced from 18.34 ± 24.68 ml to 1.35 ± 2.09 ml (P=0.0001). The VRR of all lesions was 92.06%. However, the mean number of treatments was only 1.64 ± 0.87. All patients were satisfied with the technique, with a mean satisfaction score (SC) of 9.23 ± 1.13. There were no motor function abnormalities of the related nerves. 10 patients felt numbness in the ablation area after ablation, and gradually recovered after 1 month. Conclusion: US-guided-MWA serves as a novel alternative approach for patients with VMs. Preoperative evaluation of the relationship between VMs and peripheral nerves combined with intraoperative hydrodissection is an effective and safe method to prevent nerve injury.

Landform and lithospheric development contribute to the assembly of mountain floras in China.

Although it is well documented that mountains tend to exhibit high biodiversity, how geological processes affect the assemblage of montane floras is a matter of ongoing research. Here, we explore landform-specific differences among montane floras based on a dataset comprising 17,576 angiosperm species representing 140 Chinese mountain floras, which we define as the collection of all angiosperm species growing on a specific mountain. Our results show that igneous bedrock (granitic and karst-granitic landforms) is correlated with higher species richness and phylogenetic overdispersion, while the opposite is true for sedimentary bedrock (karst, Danxia, and desert landforms), which is correlated with phylogenetic clustering. Furthermore, we show that landform type was the primary determinant of the assembly of evolutionarily older species within floras, while climate was a greater determinant for younger species. Our study indicates that landform type not only affects montane species richness, but also contributes to the composition of montane floras. To explain the assembly and differentiation of mountain floras, we propose the 'floristic geo-lithology hypothesis', which highlights the role of bedrock and landform processes in montane floristic assembly and provides insights for future research on speciation, migration, and biodiversity in montane regions.