ObjectiveTo observe the expression of Rap1, guanosine triphosphate-Rap1 (GTP-Rap1), vascular endothelial growth factor (VEGF) and β-catenin in experimental choroidal neovascularization (CNV).MethodsForty-two brown Norwegian rats were randomly divided into a blank control group (7 rats) and a model group (35 rats). Both eyes were enrolled. The CNV model was established by holmium ion laser photocoagulation in the model group. At 3, 7, 14, 21, and 28 days after photocoagulation, fluorescein fundus angiography (FFA) and choroidal vascular smear were performed to observe the degree of fluorescein leakage and CNV area in rats; Western blot and real-time quantitative polymerase chain reaction (RT-PCR) were used to detect the expression of Rap1, GTP-Rap1, VEGF, β-catenin and mRNA in CNV.ResultsThe results of FFA examination showed that a large disc-shaped fluorescein leaked in the photo-condensation spot 14 days after photocoagulation. Laser confocal microscopy showed that compared with 7 days after photocoagulation, CNV area increased at 14, 21, 28 days after photocoagulation, and the difference were statistically significant (t=3.725, 5.532, 3.605;P＜0.05). Western blot showed that there was no significant difference in the relative expression of Rap1 protein in CNV at different time points after photocoagulation between the two groups (P=0.156). Compared with the blank control group, the relative expression of GTP-Rap1 protein was significantly decreased, the relative expression of VEGF and β-catenin protein were significantly increased in the model group (P=0.000). The results of RT-PCR showed that there was no significant difference in the relative expression of Rap1 mRNA at different time points after photocoagulation between the two groups (P=0.645), but there were significant difference in the relative expression of β-catenin mRNA (P=0.000). At 7, 14, 21 and 28 days after photocoagulation, there were significant difference in the relative expression of GTP-Rap1 and VEGF mRNA between the two groups (P=0.000).ConclusionsThe expression of GTP-Rap1 in experimental CNV is significantly lower than that in normal rats.
Objective To observe the effect of shRNA interference lentivirus vector targeting rat Sirt1 gene on the expression of Sirt1 in retinal ganglion cell (RGC). Methods Four short hairpin (sh) RNA interference sequences targeting rat Sirt1 gene were designed. The target sequences of Oligo DNA were synthesized and annealed to double strand DNA, which was subsequently connected with pGLV3 lentivirus vector to build the lentiviral vector. The positive clones were identified by polymerase chain reaction (PCR) and DNA sequencing. The lentiviral vector construct and lentiviral packaging plasmids were co-transfected into 293T cells, then the titer of lentivirus were determined. The RGC were divided into 6 groups including blank group, negative control group and si-Sirt1-1, si-Sirt1-2, si-Sirt1-3, si-Sirt1-4 groups. Real-time PCR and Western blotting were used to detect the expression of Sirt1 mRNA and protein in the RGC cells. Results PCR and DNA sequencing analysis confirmed that the shRNA sequence was successfully inserted into the lentivirus vector. The concentrated titer of virus suspension was 8×108 TU/ml after the recombinant lentiviral vector successfully transfected and harvested in 293T cells. Comparing with NC group, the expression of Sirt1 mRNA and protein were significantly decreased in the si-Sirt1-1, si-Sirt1-2, si-Sirt1-3 and si-Sirt1-4 groups (F=27.682, 1 185.206; P=0.000, 0.000). The si-Sirt1-2 group had the strongest effect in reducing the expression of Sirt1 mRNA and protein. Conclusion The 4 lentiviral vectors harboring RNAi targeting rat Sirt1 gene can effectively down regulate the expression of Sirt1 mRNA and protein in RGC cells.
Objective To review the recent advances in transforming growth factor-β(TGF-β) super family study and its role in new bone formation. Methods The latest original articles related to this subject were retrieved extensively,especially the effect of TGF-β, bone morphogenetic proteins(BMPs) and activin(ACT) on distractionosteogenesis. Results TGF-β, BMPs and ACT play important roles in prompting new bone formation and each of them has different effects. Among them, TGF-β can stimulate the proliferation of osteoblast and synthesis ofextra cellular medium; BMPs can initiate the differentiation of interstitial cell toosteocyte; then ACT displays the combine effect of above two factors. Conclusion TGF-β superfamily can regulate new bone formation and thus shorten the course of mandibular distraction osteogenesis.
Objective To investigate the influence of enamel matrix proteins (EMPs) on the attachment, prol iferation and pre-mRNA of type I collagen synthesis of cultured human dermal fibroblast cells. Methods Human dermal fibroblast cells were obtained from human acrobystia and cultured in DMEM medium with 10% FBS. The 3rd to 6th passage cells were used. Ninety-six-well plates and 6-well plates were pre-coated with different concentrations of EMPs (50, 100, 150 and200 μg/ mL). ① The cell attachment experiment: 0.2 mL cells suspension at the concentration of 1 × 106/mL was added to the pre-coated 96-well plates as the experimental groups (groups A, B, C and D based on different concentrations of EMPs). At 1.5, 3.0, and 4.5 hours after inoculation, the attached cells were measured by MTT method. ② The cell prol iferation experiment: 0.2 mL cells suspension at the concentration of 5 × 104/mL was added to the pre-coated 96-well plates as the experimental groups (groups A1, B1, C1 and D1 based on the different concentrations of EMPs). At 2, 4, 6 and 8 days after inoculation, the cells were measured by MTT method. ③ The synthesis experiment of pre-mRNA: 2 mL cells at the concentration of 1 × 106/mL was added to the pre-coated 6-well plates as the experimental groups (groups A2, B2, C2 and D2 based on different concentrations of EMPs). At 5 days after inoculation, the synthesis of pre-mRNA was measured by RT-PCR method. Human dermal fibroblast cells were added to the un-coated plates as the control groups. Results ① The cell attachment experiment: There were significant differences in attachment cells between the control group, group A and the groups B, C and D (P lt; 0.05). There were no significant difference between group A and control group (P lt; 0.05). ② The cell prol iferation experiment: At 2 days, there were no significant differences in absorbance between the control group and the experimental groups (P gt; 0.05); at 4 days and 6 days, the absorbance of groups B1 (0.598 ± 0.020 and 0.639 ± 0.016 ), C1 (0.582 ± 0.017 and 0.641 ± 0.020) and D1 (0.574 ± 0.021and 0.635 ± 0.021) was significantly higher than that of the control group (0.548 ± 0.021 and 0.605 ± 0.019, P lt; 0.05); at 8 days, the absorbance of group B1 (0.629 ± 0.012) and group C1 (0.631 ± 0.014) was significantly higher than that of the control group (0.606 ± 0.031, P lt; 0.05). ③ The synthesis experiment of pre-mRNA: The synthesis of type I collage pre-mRNA of groups B2, C2 and D2 was significantly higher than that of the control group. Conclusion EMPs stimulate human dermal fibroblast cell attachment, prol iferation and synthesis of type I collage pre-mRNA, and its maximal effect can be achieved at the concentration of 100 μg /mL.
ObjectiveTo observe the short-term effects of intravitreal injection of aflibercept (IVA) for initial treatment and dressing change on exudative age-related macular degeneration (eAMD). MethodsA retrospective clinical study. From June 2018 to February 2021, forty-nine eAMD eyes of 38 patients who underwent IVA treatment in Department of Ophthalmology of Central Theater Command Hospital of People’s Liberation Army were included in the study. Among them, there were 24 males with 29 eyes and 14 females with 20 eyes; the average age was 66.82±8.71 years. All affected eyes were treated with IVA. The initial loading dose was 2.0 mg, which was injected once a month for 3 consecutive months, followed by monthly review and treatment as needed. Of the 49 eyes, 26 eyes were initially treated (initial treatment group), they were diagnosed within 3 months of the first onset and followed by IVA treatment, and no intraocular drugs and surgery were performed from the onset to the first diagnosis. Twenty-three eyes were treated with drug exchange therapy (dressing change group), they received intravitreal injection of ranibizumab and/or conbercept more than 4 times 6 months before the replacement therapy, during which there was persistent interlaminar cystoid edema and/or subretinal fluid (SRF) in the macular area and no improvement in pigment epithelial detachment (PED). Before IVA treatment, there were no statistically significant differences in the best corrected visual acuity (BCVA), foveal thickness (CMT), PED height (PEDH), and PED volume (PEDV) of the two groups of eyes before IVA treatment (P＞0.05). The same equipment and methods as before treatment were used for related examinations, and the changes of BCVA, CMT, PEDH, PEDV and complications of the two groups of eyes were recorded in 1, 3, and 6 months after treatment. The comparison of BCVA, CMT, PEDH, and PEDV between the two groups were used repeated measures analysis of variance. ResultsSix months after treatment, the number of IVA injections in the eyes of the initial treatment group and dressing change group were 4.15±0.73 and 4.39±0.72 times, respectively, and the difference was not statistically significant (t=−1.141, P=0.260). The BCVA, CMT, PEDH, and PEDV of the the initial treatment group (F=5.345, 22.995, 6.764, 5.425) and the dressing change group (F=12.519, 15.576, 8.843, 9.406) were significantly improved compared before treatment with 1, 3, and 6 months. All were statistically significant (P＜0.05). There was no significant difference in BCVA, CMT, PEDH, and PEDV between the initial treatment group and the dressing group at each time point after treatment (F=1.741, 0.069, 0.876, 3.455; P＞0.05). During the follow-up period, none of the affected eyes had complications such as persistent intraocular pressure increase, endophthalmitis, and retinal pigment epithelial tear. ConclusionsIVA can improve eyesight of patients with eAMD and reduce CMT, PEDH, and PEDV. The initial treatment and dressing change have the same effect.
In this study, we aim to investigat the effect of microgravity on osteoblast differentiation in osteoblast-like cells (MC3T3-E1). In addition, we explored the response mechanism of nuclear factor-kappa B (NF-κB) signaling pathway to " zero-g” in MC3T3-E1 cells under the simulated microgravity conditions. MC3T3-E1 were cultured in conventional (CON) and simulated microgravity (SMG), respectively. Then, the expression of the related osteoblastic genes and the specific molecules in NF-κB signaling pathway were measured. The results showed that the mRNA and protein levels of alkaline phosphatase (ALP), osteocalcin (OCN) and type Ⅰ collagen (CoL-Ⅰ) were dramatically decreased under the simulated microgravity. Meanwhile, the NF-κB inhibitor α (IκB-α) protein level was decreased and the expressions of phosphorylation of IκB-α (p-IκB-α), p65 and phosphorylation of p65 (p-p65) were significantly up-regulated in SMG group. In addition, the IL-6 content in SMG group was increased compared to CON. These results indicated that simulated microgravity could activate the NF-κB pathway to regulate MC3T3-E1 cells differentiation.
ObjectiveTo review the role and mechanism of protein factors in bone remodeling, and provides theoretical basis for further elucidating the pathogenesis and clinical treatment of bone-related diseases. MethodsThe relevant research results at home and abroad in recent years were extensively consulted, analyzed, and summarized. ResultsBone remodeling is an important physiological process to maintain bone homeostasis. Protein, as an important stimulator in bone remodeling, regulates the balance between bone resorption and bone formation. ConclusionAt present, the research on the mechanism of protein in bone remodeling is insufficient. Therefore, it is necessary to further study the specific time, process, and interaction network of protein in bone remodeling, and to confirm its mechanism in bone remodeling, so as to reveal and treat the pathogenesis of bone-related diseases.
Objective To investigate the effect of lung volume reduction surgery （LVRS） on messenger RNA expression levels of cytoskeletal proteins in diaphragmatic muscle tissues of emphysematous rabbits. Methods A total of 40 rabbits were randomly divided into 4 groups （10 rabbits in each group） ：normal control group, emphysema group, sham operation group and LVRS group. Rabbits in control group were intratracheally administered with 0.9% normal sodium, but those in other groups were intratracheally administered with 0.4% papain at the dose of 0.5 ml/kg and inhaled cigarette smoke to induce emphysema model. Then, rabbits in emphysema group were fed routinely, however, after median sternotomy , bilateral LVRS was performed in LVRS group but not in sham operation group. The mRNA expression levels of titin and nebulin in the diaphragmatic muscles of rabbits in each group were detected by reverse transcription-polymerase chain reaction（RT-PCR）. Results Compared with control group, the mRNA expression levels of titin and nebulin in the rabbit diaphragm of emphysema groups and sham operation group decreased significantly （P〈0.01 ）, so did those in LVRS group （P〈0.05）. But it increased significantly in LVRS group compared with emphysema group and sham operation group （P〈0.05）. Conclusion LVRS can increase the mRNA expression levels of titin and nebulin in diaphragmatic muscle tissues of emphysematous rabbits, which may be the associated mechanisms at the molecular level in restoring the functions of the emphysematous diaphragm by LVRS.
Objective To investigate the relationship of the expression between heat shock protein (HSP) 70 and 90, and Survivin and its effects on the proliferative activity in retinoblastoma (RB) cells. Methods Expression of Survivin, HSP70 and 90, and Ki-67 in conventional paraffin samples from 43 patients with RB and 6 healthy people was detected by streptavidin-biotin peroxidase (SP) immunohistochemical method. Ki67 labeling index was used to evaluate the proliferative activity in RB. Results In 43 cases of RB, positive expression of HSP70 and 90 and Survivin was found in 28 (65.12%), 37 (86.05%) and 27 (62.79%) cases, respectively. None of the 6 normal retinal tissue expressed HSP70, HSP90 or Survivin. Positive expression of Survivin was more frequent in positive expressions of HSP90 than that in negative expressions of HSP90 (P＜0.05). Ki67 labeling index was higher in positive expressions of HSP90 and positive expressions of Survivin than that in their negative expressions respectively (P＜0.05). Meanwhile, higher Ki67 labeling index was found in positive HSP90Survivin expressions than that in negative HSP90Survivin expressions and those cases where only HSP90 or Survivin was found (P＜0.05). Expression of HSP70 did not correlate with that of Survivin, nor had any significant effect on Ki67 labeling index (P＞0.05). Expression of HSPs and Survivin and Ki67 labeling index did not correlate with histological types (P＞0.05). Conclusion Expression of HSP90 correlates with that of Survivin in RB. Co-existence of Survivin and HSP90 probably plays an important role in the genesis of RB.
OBJECTIVE: To clarify the mechanisms of the signal transduction of bone morphogenetic proteins (BMPs) inducing bone formation and to provide theoretical basis for basic and applying research of BMPs. METHOD: We looked up the literature of the role of Smads and related transcription factors in the signal transduction of BMPs inducing bone formation. RESULTS: The signal transduction processes of BMPs included: 1. BMPs combined with type II and type I receptors; 2. the type I receptor phosphorylated Smads; and 3. Smads entered the cell nucleus, interacted with transcription factors and influenced the transcription of related proteins. Smads could be divided into receptor-regulated Smads (R-Smads: Smad1, Smad2, Smad3, Smad5, Smad8 and Smad9), common-mediator Smad (co-Smad: Smad4), and inhibitory Smads (I-Smads: Smad6 and Smad7). Smad1, Smad5, Smad8, and probable Smad9 were involved in the signal transduction of BMPs. Multiple kinases, such as focal adhesion kinase (FAK), Ras-extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K), and Akt serine/threonine kinase were related to Smads signal transduction. Smad1 and Smad5 related with transcription factors included core binding factor A1 (CBFA1), smad-interacting protein 1 (SIP1), ornithine decarboxylase antizyme (OAZ), activating protein-1 (AP-1), xenopus ventralizing homeobox protein-2 (Xvent-2), sandostatin (Ski), antiproliferative proteins (Tob), and homeodomain-containing transcriptian factor-8 (Hoxc-8), et al. CBFA1 could interact with Smad1, Smad2, Smad3, and Smad5, so it was involved in TGF-beta and BMP-2 signal transduction, and played an important role in the bone formation. Cleidocranial dysplasia (CCD) was thought to be caused by heterozygous mutations in CBFA1. The CBFA1 knockout mice showed no osteogenesis and had maturational disturbance of chondrocytes. CONCLUSION: Smads and related transcription factors, especially Smad1, Smad5, Smad8 and CBFA1, play an important role in the signal transduction of BMPs inducing bone formation.