Characteristics of Retinal Vascular Degeneration and the Expression of Vessel-Related Claudin Proteins in Retinal Degeneration Mouse.

INTRODUCTION: This study aimed to investigate the characteristics of retinal vascular degeneration and the expression of vessel-related Claudin (CLD) proteins in retinal degeneration mouse ( Pde6ßrd1/rd1 rd1 mouse). METHODS: Retinas from wild-type (WT) mice and rd1 mice at postnatal day 3 (P3), P5, P8, P11, P13, P15, P18, and P21 were collected. Immunofluorescence staining was used to assess the retinal vascular plexus, cell proliferation, CLD expression, and retinal ganglion cells (RGCs). The distribution of retinal superficial and deep vessels was determined by Isolectin B4 fluorescence staining of retinal flat mounts and frozen sections. Hematoxylin and eosin staining and terminal deoxynucleotidyl transferase-mediated dNTP nick end labeling were used to investigate retinal histological degeneration and apoptosis in rd1 mice respectively. Quantitative real-time PCR and western blot were used to measure the expression of vessel-related CLD-1, 2, 3 and CLD-5, vascular endothelial growth factor A (VEGFA), and vascular endothelial growth factor receptor 2 (VEGFR2) in the retinas. RESULTS: Compared to the WT mice, the rd1 mice displayed delayed but completed progressive development in the retinal superficial vascular plexuses (SVP) and deep vascular plexuses (DVP). In the rd1 mice, the thickness of retinal layers gradually decreased and the retinas underwent progressive atrophy and degeneration. The deterioration got worse at the late developmental stage. The declined vessel density of SVP and DVP correlated with the decreased thickness of the full and inner parts of the retina and the reduced number of RGCs. DVP degeneration and the thinning of the outer nuclear layer occurred an obvious reduction at P15. The expression levels of CLD-1, CLD-2, CLD-3, CLD-5, VEGFA, and VEGFR2 decreased and were consistently lower in the rd1 mice than in WT mice since P15. CONCLUSION: Rd1 mice exhibited progressive vascular degeneration of retinal SVP and DVP, the thinning and atrophy of retinal ONL and RGC, and the downregulation of vessel-related CLD proteins during the late developmental period. Thus, the rd1 mouse is a useful model of not only retinal neuro-degeneration but also retinal vascular degeneration.

FTH1 protects against osteoarthritis by MAPK pathway inhibition of extracellular matrix degradation.

OBJECTIVE: Ferritin heavy chain 1 (FTH1) is an important subunit of ferro-storing proteins and is indispensable for iron metabolism. Though it has been extensively studied in numerous organs and diseases, the relationship between FTH1 and osteoarthritis (OA) is unclear. DESIGN: Primary murine chondrocytes and cartilage explants were treated with FTH1 siRNA for 72 h. Mice were injected with adenovirus expressing FTH1 after destabilized medial meniscus (DMM) surgery. These approaches were used to determine the effect of FTH1 expression on the pathophysiology of OA. RESULTS: FTH1 expression was down regulated in OA patients and mice after DMM surgery. Knock down of FTH1 induced articular cartilage damage and extracellular matrix degradation in cartilage explants. Further, over expression of FTH1 reduced the susceptibility of chondrocytes to ferroptosis and reversed decrements in SOX9 and aggrecan after DMM surgery. Moreover, FTH1 relieved OA by inhibition of the chondrocyte MAPK pathway. CONCLUSION: This study found FTH1 to play an essential role in extracellular matrix degradation, ferroptosis, and chondrocytes senescence during OA progression. Further, injection of adenovirus expressing FTH1 may be a potential strategy for OA prevention and therapy.

Downregulation of miR-124-3p suppresses the development of the deep retinal blood vessels by enhancing the Stat1/Ripk1 pathway in mouse retinal microglia.

The study aimed to investigate the role of microRNA (miR)-124-3p in retinal angiogenesis in a mouse model. An intravitreal injection of miR-124-3p antagomir was used to knockdown the expression of miR-124-3p in the mouse retina at postnatal day (P)3. Immunofluorescent staining of both retinal frozen sections and whole retina were used to observe retinal vascular development in the P6, P9 and P12 mice, as well as the changes in retinal ganglion cells, astrocytes, Müller cells and microglia. Whole retinal RNA extracted from P9 mice was used for transcriptome sequencing. Following gene set enrichment analysis, the enriched genes caused by miR-124-3p inhibition were analyzed by immunofluorescent staining and western blot. Results indicated that deep vascular development was significantly inhibited by the activation of M1 phenotype microglia. Moreover, there were no notable effects on superficial retinal vascular development, the retinal ganglion cells, astrocytes, and Müller cells. The expression of the Stat1/Irf9/Eif2ak2/Ripk1 axis in the miR-124-3p knockdown group was significantly increased. The microglia penetrated deep into the retina and the activation of Ripk1(+) microglia significantly increased, which was accompanied by an increased level of apoptosis to inhibit the deep vascular sprout. Downregulation of miR-124-3p during the early retinal development can suppress the development of the deep retinal blood vessels by enhancing the expression level of the Stat1/Irf9/Eif2ak2/Ripk1 axis and inducing the cell apoptosis of the activation of Ripk1(+) microglia.

Downregulation of miR-210-3p Attenuates High Glucose-Induced Angiogenesis of Vascular Endothelial Cells via Targeting FGFRL1.

INTRODUCTION: Vascular endothelial cell injury and angiogenesis induced by hyperglycemia are the main pathological basis of vascular complications in diabetes mellitus. Our study aimed to investigate the role and mechanism of miR-210-3p in high glucose (HG)-induced angiogenesis. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with HG to mimic the pathological process of hyperglycemia. HUVECs were divided into the control group, HG group, HG+inhibitor-NC group, and HG+miR-210-3p inhibitor group. Proliferation and migration were tested by wound healing assay, tube formation, and Transwell assay. Quantitation real-time PCR and Western blots were performed to determine the expression of miR-210-3p and relative proteins, respectively. RESULTS: The level of miR-210-3p significantly increased in HUVECs treated by HG. The knockdown of miR-210-3p attenuated the tube formation, proliferation, and migration of cultured HUVECs in vitro to inhibit angiogenesis by increasing the expression of fibroblast growth factor receptor-like 1 (FGFRL1) and then attenuating the phosphorylation of signal transducer and activator of transcription 3 (STAT3), extracellular regulated protein kinases, and protein kinase B (Akt). CONCLUSION: Our study revealed that miR-210-3p might be a promising target for treating diabetic-associated vascular injury.

MicroRNA-124-3p Attenuated Retinal Neovascularization in Oxygen-Induced Retinopathy Mice by Inhibiting the Dysfunction of Retinal Neuroglial Cells through STAT3 Pathway.

MicroRNA (miRNA) is a non-coding RNA that can regulate the expression of many target genes, and it is widely involved in various important physiological activities. MiR-124-3p was found to associate with the normal development of retinal vessels in our previous study, but the mechanism of its anti-angiogenic effect on pathological retinal neovascularization still needed to be explored. Therefore, this study aimed to investigate the effect and mechanism of miR-124-3p on retinal neovascularization in mice with oxygen-induced retinopathy (OIR). Here, we found that intravitreal injection of miR-124-3p agomir attenuated pathological retinal neovascularization in OIR mice. Moreover, miR-124-3p preserved the astrocytic template, inhibited reactive gliosis, and reduced the inflammatory response as well as necroptosis. Furthermore, miR-124-3p inhibited the signal transducer and activator of transcription 3 (STAT3) pathway and decreased the expression of hypoxia-inducible factor-1α and vascular endothelial growth factor. Taken together, our results revealed that miR-124-3p inhibited retinal neovascularization and neuroglial dysfunction by targeting STAT3 in OIR mice.

Asporin regulated by miR-26b-5p mediates chondrocyte senescence and exacerbates osteoarthritis progression via TGF-ß1/Smad2 pathway.

OBJECTIVES: This study aimed to investigate the role and mechanism of asporin in modulating chondrocyte senescence in OA pathology. METHODS: Asporin and senescence-related hallmark expression were examined in human and experimental OA mouse cartilage samples. Twelve-week-old male C57 mice were administered with recombinant protein (rm-asporin)- or asporin-siRNA-expressing lentiviruses via intra-articular injection once a week after destabilization of the medial meniscus (DMM) surgery to induce OA. Cartilage damage was measured using the Osteoarthritis Research Society International score. Senescence-associated ß-galactosidase (SA-ß-Gal) staining, γH2AX, p21 and p16INK4a were analysed by immunofluorescence staining and western blot to assess the specific role of asporin in chondrocyte senescence. The TGF-ß1-Smad2 signalling pathway and miR-26b-5p were further evaluated to explore the mechanism of asporin in OA. RESULTS: Asporin was upregulated in articular chondrocytes of OA patients and DMM mice and accompanied by accumulation of senescent cells. Asporin overexpression exaggerated OA progression, whereas silencing asporin restored chondrocyte homeostasis and deferred chondrocyte senescence, leading to markedly attenuated DMM-induced OA. Cellular and molecular analyses showed that asporin can be inhibited by miR-26b-5p, which was significantly downregulated in OA cartilage, leading to exacerbation of experimental OA partially through inhibition of TGF-ß1-Smad2 signalling in chondrocytes. CONCLUSIONS: Our findings indicate that asporin plays an essential role in chondrocyte senescence and OA pathogenesis. Upregulated by miR-26b-5p, asporin inhibits the TGF-ß1-Smad2 pathway to accelerate chondrocyte senescence and exacerbate cartilage degeneration. Targeting the miR-26b-5p-asporin-Smad2 axis may serve as a practical therapeutic strategy to delay chondrocyte senescence and OA development.

The application of platelet-rich plasma in the treatment of knee osteoarthritis: A literature review.

BACKGROUND: Primary knee osteoarthritis remains a difficult-to-control degenerative disease. With the rise in average life expectancy and the incidence of obesity, osteoarthritis has brought an increasing economic and physical burden on people. This article summarizes the latest understanding of platelet-rich plasma in the treatment of knee osteoarthritis, and reviews the economic issues of PRP. METHODS: The literatures in Pubmed, Embase, Cochrane library, Web-science and other databases were searched, and literature inclusion and exclusion criteria were formulated. According to the Cochrane systematic reviewer's manual, the included literatures were grouped, and qualitative descriptions and quantitative meta-analysis were performed. Continuous statistical methods were used to compare the effects and adverse effects of PRP before and after treatment, as well as between PRP and other conservative treatments. RESULTS: A total of 12 randomized controlled trials were included in this study. A total of 959 KOA patients (1070 knees) were enrolled and followed for 3-12 months. PRP total knee scores were significantly better than baseline at 1, 2, 3, 6 and 12 months after treatment (1 month: SMD = 0.60, P < 0.01; 2 months: SMD = 0.98, P < 0.01; 3 months: SMD = 1.16, P < 0.01; 6 months: SMD = 1.49, P < 0.01; 12 months: SMD = 1.47, P < 0.01). In terms of adverse reactions, PRP did not increase the risk of adverse events compared with HA (OR = 0.96, P = 0.85). CONCLUSIONS: Compared with many other treatment methods, intra-articular injection of PRP has been proven to be safe and effective to improve the quality of life of patients with KOA.

Identification of the aberrantly methylated differentially expressed genes in proliferative diabetic retinopathy.

Diabetic retinopathy (DR) is the most common complication of diabetes. Proliferative DR (PDR) is a more advanced stage of DR, which can cause severe impaired vision and even blindness. However, the precise pathological mechanisms of PDR remain unknown. DNA methylation serves an important role in the initiation and progression of numerous types of disease including PDR. The purpose of this study was to identify the aberrantly methylated differentially expressed genes (DEGs) as potential therapeutic targets of PDR. The gene expression microarray dataset GSE60436 and the methylation profiling microarray dataset GSE57362 were used to determine the aberrantly methylated DEGs in PDR, utilizing normal retinas as controls and fibrovascular membranes (FVMs) in patients with PDR as PDR samples. The functional term and signaling pathway enrichment analysis of the selected genes were subsequently performed. In addition, protein-protein interaction (PPI) networks were constructed to determine the hub genes, and the network of transcriptional factor (TF) and target hub genes was also analyzed. In total, 132 hypomethylated genes were found to be upregulated, whereas 172 hypermethylated genes were discovered to be downregulated in PDR. The hypomethylated upregulated genes were found to be enriched in the pathways, such as "cell-substrate adhesion", "adherens junction", "cell adhesion molecule binding" and "extracellular matrix receptor interactions". Meanwhile, the hypermethylated downregulated genes were enriched in the pathways, such as "visual perception", "presynapse" and the "synaptic vesicle cycle". Based on the PPI analysis, a total of eight hub genes were identified: CTGF, SERPINH1, LOX, RBP3, OTX2, RPE65, OPN1SW and NRL. It was hypothesized that the aberrant methylation of these genes might be related to the possible pathophysiology of PDR. An important transcriptional factor, TFDP1, was discovered to share the closest interactions with the hub genes from the gene-TF network. In conclusion, the present study identified an association among DNA methylation and gene expression in PDR using bioinformatics analysis, and identified the hub genes which might be potential methylation-based diagnosis and treatment targets for PDR in the near future.

The role of cldnh during the early retinal development in zebrafish.

Claudin-3, an integral component of tight junction, has recently been shown to be expressed in retinal ganglion cells, retinal pigment cells, and retinal vascular endothelial cells. However, the role of claudin-3 in the development of the neural retina and its vessels remains undefined. This study aimed to investigate the role of zebrafish claudin-h (cldnh), the closest ortholog of mouse and human claudin-3, in the development of the neural retina and its vessels. Cldnh levels in green fluorescent protein transgenic zebrafish were genetically manipulated by cldnh morpholino oligonucleotide (MO) and cldnh mRNA to investigate gene function. The expression of cldnh was analyzed using polymerase chain reaction and immunofluorescence staining. The altered morphological, cellular and molecular events in the cldnh MO-morphant eyes were detected using hematoxylin-eosin staining, fluorescent dye injection, confocal in vivo imaging, BrdU labeling, TUNEL assay, RNA sequencing, and Western blot. We demonstrated that the cldnh protein was expressed in the neural retina and the hyaloid vessel which is the predecessor of the retinal vessel in zebrafish. Cldnh knockdown delayed lamination of the neural retina and reduced its thickness, which might be associated with the downregulation of the retinal development-related genes of atoh7, pcdh17, crx, neurod1, insm1a, sox9b and cdh11, and the upregulation of the cell cycle and apoptosis-associated genes of tp53, cdkn1a and casp8. Cldnh knockdown also reduced the density and interrupted the lumenization of the hyaloid vessels, which might be owing to the downregulation of the vessel formation-related genes of hlx1 and myl7. In conclusion, cldnh was required for the normal development of the neural retina and its vessels in zebrafish, providing a basis for elucidating its role in the pathogenesis of retinal vascular or inflammatory diseases.

Blocking PI3K/AKT signaling inhibits bone sclerosis in subchondral bone and attenuates post-traumatic osteoarthritis.

PI3K/AKT signaling is essential in regulating pathophysiology of osteoarthritis (OA). However, its potential modulatory role in early OA progression has not been investigated yet. Here, a mouse destabilization OA model in the tibia was used to investigate roles of PI3K/AKT signaling in the early subchondral bone changes and OA pathological process. We revealed a significant increase in PI3K/AKT signaling activation which was associated with aberrant bone formation in tibial subchondral bone following destabilizing the medial meniscus (DMM), which was effectively prevented by treatment with PI3K/AKT signaling inhibitor LY294002. PI3K/AKT signaling inhibition attenuated articular cartilage degeneration. Serum and bone biochemical analyses revealed increased levels of MMP-13, which was found expressed mainly by osteoblastic cells in subchondral bone. However, this MMP-13 induction was attenuated by LY294002 treatment. Furthermore, PI3K/AKT signaling was found to enhance preosteoblast proliferation, differentiation, and expression of MMP-13 by activating NF-κB pathway. In conclusion, inhibition of PI3K/AKT/NF-κB axis was able to prevent aberrant bone formation and attenuate cartilage degeneration in OA mice.

Association of IGFN1 variant with polypoidal choroidal vasculopathy.

BACKGROUND: Polypoidal choroidal vasculopathy (PCV) and neovascular age-related macular degeneration (nAMD) share a similar phenotype but are different in their clinical manifestations, responses to treatment and prognosis. Whether PCV is a subtype of AMD or a distinct entity from nAMD remains unknown. Therefore, we performed a whole-exome sequencing based association analysis to compare the genetic architecture of PCV and nAMD in Han Chinese. METHODS: Whole-exome sequencing analysis was performed on 21 nAMD cases, 20 PCV cases and 20 healthy controls. As a follow-up validation, 145 nAMD cases, 160 PCV cases and 193 controls were genotyped using the Sequenom MassARRAY platform (Sequenom, San Diego, CA, USA). RESULTS: A novel variant, c.6196A>G in the IGFN1 gene, was significantly associated with only PCV (combined p = 7.1 × 10-11 , odds ratio = 9.44), but not with nAMD (combined p = 0.683, odds ratio = 1.30). The minor allele G conferred an increased risk of PCV. CONCLUSIONS: The findings of the present study indicate that, although some of the susceptibility loci are shared between PCV and nAMD, a unique genetic signature may decide the pathogenesis of PCV.

Synovial macrophage M1 polarisation exacerbates experimental osteoarthritis partially through R-spondin-2.

OBJECTIVES: To investigate the roles and regulatory mechanisms of synovial macrophages and their polarisation in the development of osteoarthritis (OA). METHODS: Synovial tissues from normal patients and patients with OA were collected. M1 or M2-polarised macrophages in synovial tissues of patients with OA and OA mice were analysed by immunofluorescence and immunohistochemical staining. Mice with tuberous sclerosis complex 1 (TSC1) or Rheb deletion specifically in the myeloid lineage were generated and subjected to intra-articular injection of collagenase (collagenase-induced osteoarthritis, CIOA) and destabilisation of the medial meniscus (DMM) surgery to induce OA. Cartilage damage and osteophyte size were measured by Osteoarthritis Research Society International score and micro-CT, respectively. mRNA sequencing was performed in M1 and control macrophages. Mice and ATDC5 cells were treated with R-spondin-2 (Rspo2) or anti-Rspo2 to investigate the role of Rspo2 in OA. RESULTS: M1 but not M2-polarised macrophages accumulated in human and mouse OA synovial tissue. TSC1 deletion in the myeloid lineage constitutively activated mechanistic target of rapamycin complex 1 (mTORC1), increased M1 polarisation in synovial macrophages and exacerbated experimental OA in both CIOA and DMM models, while Rheb deletion inhibited mTORC1, enhanced M2 polarisation and alleviated CIOA in mice. The results show that promoting the macrophage M1 polarisation leads to exacerbation of experimental OA partially through secretion of Rspo2 and activation of ß-catenin signalling in chondrocytes. CONCLUSIONS: Synovial macrophage M1 polarisation exacerbates experimental CIOA partially through Rspo2. M1 macrophages and Rspo2 are potential therapeutic targets for OA treatment.

Myostatin serum concentrations are correlated with the severity of knee osteoarthritis.

OBJECTIVE: Myostatin, a member of the transforming growth factor-ß family, contributes to joint deterioration in mice. Thus, we aimed to assess the correlation of myostatin concentrations with the presence and severity of knee osteoarthritis (OA). MATERIAL AND METHODS: We determined serum and synovial fluid (SF) myostatin concentrations in a population of 184 patients with knee OA and 109 healthy controls. RESULTS: The knee OA group presented with higher serum myostatin concentrations than the controls. Knee OA patients with KL grade 4 showed higher serum and SF myostatin concentrations compared with those with KL grade 2 and 3. Knee OA patients with KL grade 3 had higher serum and SF myostatin concentrations compared with those with KL grade 2. Serum and SF myostatin concentrations were significantly correlated with KL grading. CONCLUSION: Serum and SF myostatin concentrations were correlated with the presence and severity of knee OA.

A modular hydrogel bioink containing microsphere-embedded chondrocytes for 3D-printed multiscale composite scaffolds for cartilage repair.

Articular cartilage tissue engineering is being considered an alternative treatment strategy for promoting cartilage damage repair. Herein, we proposed a modular hydrogel-based bioink containing microsphere-embedded chondrocytes for 3D printing multiscale scaffolds integrating the micro and macro environment of the native articular cartilage. Gelatin methacryloyl (GelMA)/alginate microsphere was prepared by a microfluidic approach, and the chondrocytes embedded in the microspheres remained viable after being frozen and resuscitated. The modular hydrogel bioink could be printed via the gel-in-gel 3D bioprinting strategy for fabricating the multiscale hydrogel-based scaffolds. Meanwhile, the cells cultured in the scaffolds showed good proliferation and differentiation. Furthermore, we also found that the composite hydrogel was biocompatible in vivo. These results indicated that the modular hydrogel-based bioinks containing microsphere-embedded chondrocytes for 3D printing multiscale scaffolds could provide a 3D multiscale environment for enhancing cartilage repairing, which would be encouraging considering the numerous alternative applications in articular cartilage tissue engineering.

Choroidal thickness in both eyes of patients with unilateral idiopathic macular hole.

PURPOSE: To compare the choroidal thickness in the macular area in eyes with an idiopathic macular hole (IMH) with that of unaffected fellow eyes and eyes of healthy controls. DESIGN: A cross-sectional study. PARTICIPANTS: Fifty patients with unilateral IMH and 50 healthy controls. METHODS: Enhanced depth imaging was obtained by spectral-domain optical coherence tomography in all patients and controls. Eyes were divided into 3 groups: 50 eyes in group A (affected eyes with IMH), 48 eyes in group B (unaffected fellow eyes), and 50 eyes in group C (right eyes of age- and sex-matched controls). MAIN OUTCOME MEASURES: Two independent graders individually measured the choroidal thickness. Choroidal thickness was measured from the posterior edge of the retinal pigment epithelium to the choroid-scleral junction in the subfoveal area and 1 and 3 mm away from the fovea in the superior, inferior, nasal, and temporal regions. Apical and basal diameters of macular holes (MHs) were measured in eyes with IMH. Statistical analysis was conducted to compare mean choroidal thicknesses. RESULTS: Choroidal thickness was significantly decreased in affected IMH eyes compared with unaffected fellow eyes in 48 patients (P = 0.005, paired t test). The mean subfoveal choroidal thickness (SFCT) was 206.82 ± 67.09 µm in group A, 228.34 ± 80.71 µm in group B, and 248.88 ± 63.10 µm in group C. The choroid was significantly thinner in group A (P = 0.002) than in group C. The SFCT in unaffected fellow eyes was lower than in controls, but without statistical significance (P = 0.177). The apical and basal size of the MH were not related to the underlying choroidal thickness (apical r=-0.267, P = 0.072; basal r = -0.259, P = 0.082). CONCLUSIONS: Choroidal thickness was thinner in affected eyes with IMH and in fellow unaffected eyes. This may suggest a contributing role of the perfusion of the choroid in the pathogenesis of IMH. If these findings are confirmed, we suggest that the fellow eyes with thinner choroid may be prone to IMH and should be followed up frequently.

[Relationship between gender and posterior pole choroidal thickness in normal eyes].

OBJECTIVE: To investigate and compare the choroidal thickness between healthy male and female subjects. METHOD: Six-hundred and twenty eyes of 310 healthy volunteers with no ophthalmic disease history were recruited, including 152 males and 158 females. All volunteers were subgrouped into Group A to F according to their ages. Enhanced depth imaging choroidal scans were obtained in all eyes by using spectral-domain optical coherence tomography. Subfoveal choroidal thickness (SFCT) and choroidal thickness at 1 mm/3 mm superior, inferior, nasal and temporal to the fovea were measured. Choroidal thickness was compared between male and female in the subgroups with different age. RESULTS: Mean SFCT was higher in 152 males (298.02 ± 101.47) µm than that in 158 females (256.28 ± 90.87) µm with statistically significant difference (t' = 4.853, P < 0.05). Choroid at 1 mm and 3 mm from the fovea were also thicker in the male (t' = 5.050, t = 4.597, t = 5.225, t = 5.363, t = 5.608, t' = 4.239, t = 4.108, t' = 5.589; P < 0.05). In any subgroup from A to E, SFCT in male was significantly thicker than female, after adjusted for refractive error (t = 2.343, t' = 2.163, t = 3.239, t = 2.181, t' = 2.982; P < 0.05). In Group F, mean SFCT in male was thicker than female, but without statistical significance (t' = 0.681, P > 0.05). CONCLUSIONS: Gender was one of the factors that affect the choroid thickness in healthy populations. In subjects under 70, male have thicker choroid than female. This result at least partially explained the gender predilection of macular diseases, such as central serous chorioretinopathy and idiopathic macular hole.

The Modified Longitudinal Capsulotomy by Outside-In Approach in Hip Arthroscopy for Femoroplasty and Acetabular Labrum Repair-A Cohort Study.

Hip arthroscopy is difficult to perform due to the limited arthroscopic view. To solve this problem, the capsulotomy is an important technique. However, the existing capsulotomy approaches were not perfect in the surgical practice. Thus, this study aimed to propose a modified longitudinal capsulotomy by outside-in approach and demonstrate its feasibility and efficacy in arthroscopic femoroplasty and acetabular labrum repair. A retrospective cohort study was performed and twenty-two postoperative patients who underwent hip arthroscopy in our hospital from January 2019 to December 2021 were involved in this study. The patients (14 females and 8 males) had a mean age of 38.26 ± 12.82 years old. All patients were diagnosed cam deformity and labrum tear in the operation and underwent arthroscopic femoroplasty and labrum repair by the modified longitudinal capsulotomy. The mean follow-up time was 10.4 months with a range of 6−12 months. There were no major complications, including infection, neurapraxias, hip instability or revision in any patients. The average mHHS were 74.4 ± 15.2, 78.2 ± 13.7 and 85.7 ± 14.5 in 3 months, 6 months and 12 months after surgery, respectively, which were all better than that before surgery (44.9 ± 8.6) (p < 0.05). The average VAS were 2.8 ± 1.2, 1.5 ± 0.6 and 1.2 ± 0.7 in 3 months, 6 months and 12 months after surgery, respectively, which were all lower than that before surgery (5.5 ± 2.0) (p < 0.05). The modified longitudinal capsulotomy by outside-in approach is proved to be a safe and feasible method for hip arthroscopy considering to the feasibility, efficacy and security. The arthroscopic femoroplasty and labrum repair can be performed conveniently by this approach and the patient reported outcomes after surgery were better that before surgery in short-term follow-up. This new method is promising and suggested to be widely used clinically.

Proteomic Analysis of Retinal Conditioned Medium: The Effect on Early Differentiation of Embryonic Stem Cells into Retina.

Stem cell replacement therapy has emerged as one of the most promising treatment options for retinal degenerative diseases, which are the main causes of irreversible vision loss. Three-dimensional (3D) retinal organoid culture is a cutting-edge technology for differentiating embryonic stem cells into retinal cells by forming a laminated retinal structure. However, 3D culture systems have strict requirements with respect to the experimental environment and culture technologies. Our study aimed to investigate the effect of retinal conditioned medium (RCM) at different developmental stages on the early differentiation of embryonic stem cells into retina in a 3D culture system. In this study, we added RCM to the 3D culture system and found that it could promote the differentiation of mouse embryonic stem cells (mESCs) into neuroretina. We further explored the possible mechanisms of RCM that regulate differentiation through proteomic analysis. RCM at different time points disclosed different protein profiles. Proteins which improved energy metabolism of mESCs might help improve the viability of embryonic bodies. We then screened out Snap25, Cntn1, Negr1, Dpysl2, Dpysl3, and Crmp1 as candidate proteins that might play roles in the differentiation and neurogenesis processes of mESCs, hoping to provide a basis for optimizing a retinal differentiation protocol from embryonic stem cells.

An Interaction-Based Method for Refining Results From Gene Set Enrichment Analysis.

Purpose: To demonstrate an interaction-based method for the refinement of Gene Set Enrichment Analysis (GSEA) results. Method: Intravitreal injection of miR-124-3p antagomir was used to knockdown the expression of miR-124-3p in mouse retina at postnatal day 3 (P3). Whole retinal RNA was extracted for mRNA transcriptome sequencing at P9. After preprocessing the dataset, GSEA was performed, and the leading-edge subsets were obtained. The Apriori algorithm was used to identify the frequent genes or gene sets from the union of the leading-edge subsets. A new statistic d was introduced to evaluate the frequent genes or gene sets. Reverse transcription quantitative PCR (RT-qPCR) was performed to validate the expression trend of candidate genes after the knockdown of miR-124-3p. Results: A total of 115,140 assembled transcript sequences were obtained from the clean data. With GSEA, the NOD-like receptor signaling pathway, C-type-like lectin receptor signaling pathway, phagosome, necroptosis, JAK-STAT signaling pathway, Toll-like receptor signaling pathway, leukocyte transendothelial migration, chemokine signaling pathway, NF-kappa B signaling pathway and RIG-I-like signaling pathway were identified as the top 10 enriched pathways, and their leading-edge subsets were obtained. After being refined by the Apriori algorithm and sorted by the value of the modulus of d , Prkcd, Irf9, Stat3, Cxcl12, Stat1, Stat2, Isg15, Eif2ak2, Il6st, Pdgfra, Socs4 and Csf2ra had the significant number of interactions and the greatest value of d to downstream genes among all frequent transactions. Results of RT-qPCR validation for the expression of candidate genes after the knockdown of miR-124-3p showed a similar trend to the RNA-Seq results. Conclusion: This study indicated that using the Apriori algorithm and defining the statistic d was a novel way to refine the GSEA results. We hope to convey the intricacies from the computational results to the low-throughput experiments, and to plan experimental investigations specifically.

Effect of secretory leucocyte protease inhibitor on early tendon-to-bone healing after anterior cruciate ligament reconstruction in a rat model.

AIMS: To verify whether secretory leucocyte protease inhibitor (SLPI) can promote early tendon-to-bone healing after anterior cruciate ligament (ACL) reconstruction. METHODS: In vitro: the mobility of the rat bone mesenchymal stem cells (BMSCs) treated with SLPI was evaluated by scratch assay. Then the expression levels of osteogenic differentiation-related genes were analyzed by real-time quantitative PCR (qPCR) to determine the osteogenic effect of SLPI on BMSCs. In vivo: a rat model of ACL reconstruction was used to verify the effect of SLPI on tendon-to-bone healing. All the animals of the SLPI group and the negative control (NC) group were euthanized for histological evaluation, micro-CT scanning, and biomechanical testing. RESULTS: SLPI improved the migration ability of BMSCs and upregulated the expression of genes related to osteogenic differentiation of BMSCs in vitro. In vivo, the SLPI group had higher histological scores at the tendon-bone interface by histological evaluation. Micro-CT showed more new bone formation and bone ingrowth around the grafted tendon in the SLPI group. Evaluation of the healing strength of the tendon-bone connection showed that the SLPI group had a higher maximum failure force and stiffness. CONCLUSION: SLPI can effectively promote early tendon-to-bone healing after ACL reconstruction via enhancing the migration and osteogenic differentiation of BMSCs. Cite this article: Bone Joint Res 2022;11(7):503-512.