AIM:To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptorβ(PDGFRβ)signaling pathway in r...AIM:To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptorβ(PDGFRβ)signaling pathway in retinal pericytes on photoreceptor loss and Müller glial response.METHODS:Sprague-Dawley rats were exposed to intense light to induce retinal injury.Neutralizing antibody against PDGFRβwere deployed to block the signaling pathway in retinal pericytes through intravitreal injection.Retinal histology and Müller glial reaction were assessed following light injury.In vitro,normal and PDGFRβ-blocked retinal pericytes were cocultured with Müller cell line(rMC-1)to examine morphological and protein expression changes upon supplementation with light-injured supernatants of homogenized retinas(SHRs).RESULTS:PDGFRβblockage 24h prior to intense light exposure resulted in a significant exacerbation of photoreceptor loss.The upregulation of GFAP and p-STAT3,observed after intense light exposure,was significantly inhibited in the PDGFRβblockage group.Fur ther upregulation of cytokines monocyte chemoattractant protein 1(MCP-1)and interleukin-1β(IL-1β)was also observed following PDGFRβinhibition.In the in vitro coculture system,the addition of light-injured SHRs induced pericyte deformation and upregulation of proliferating cell nuclear antigen(PCNA)expression,while Müller cells exhibited neuron-like morphology and expressed Nestin.However,PDGFRβblockage in retinal pericytes abolished these cellular responses to light-induced damage,consistent with the in vivo PDGFRβblockage findings.CONCLUSION:Pericyte-Müller glia interaction plays a potential role in the endogenous repair process of retinal injury.Impairment of this interaction exacerbates photoreceptor degeneration in light-induced retinal injury.展开更多
In recent years, people have become increasingly attentive to light pollution influences on their eyes. In the visible spectrum, short-wave blue light with wavelength between 415 nm and 455 nm is closely related to ey...In recent years, people have become increasingly attentive to light pollution influences on their eyes. In the visible spectrum, short-wave blue light with wavelength between 415 nm and 455 nm is closely related to eye light damage. This high energy blue light passes through the cornea and lens to the retina causing diseases such as dry eye, cataract, age-related macular degeneration, even stimulating the brain, inhibiting melatonin secretion, and enhancing adrenocortical hormone production, which will destroy the hormonal balance and directly affect sleep quality. Therefore, the effect of Blu-rays on ocular is becoming an important concern for the future. We describe blue light’s effects on eye tissues, summarize the research on eye injury and its physical prevention and medical treatment.展开更多
Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, t...Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, the sciatic nerve on one side of Wistar rats was treated with low tem- peratures （3-5℃） for 2 hours. The contralateral sciatic nerve was used as a control. We assessed changes in the nerves using Evans blue as a fluid tracer and morphological methods. Excess fluid was found in the endoneurium 1 day after cold injury, though the tight junctions between cells remained closed. From 3 to 5 days after the cold injury, the fluid was still present, but the tight junctions were open. Less tracer leakage was found from 3 to 5 days after the cold injury compared with 1 day after injury. The cold injury resulted in a breakdown of the blood-nerve barrier func- tion, which caused endoneurial edema. However, during the early period, the breakdown of the blood-nerve barrier did not include the opening of tight junctions, but was due to other factors. Excessive fluid volume produced a large increase in the endoneurial fluid pressure, prevented liquid penetration into the endoneurium from the microvasculature. These results suggest that drug treatment to patients with cold injuries should be administered during the early period after injury because it may be more difficult for the drug to reach the injury site through the microcirculation after the tissue fluid pressure becomes elevated.展开更多
Complete transection of peripheral mixed nerves immediately produces loss of sensory perception,muscle contractions and voluntary behavior mediated by the severed distal axons.In contrast to natural regeneration(~1 mm...Complete transection of peripheral mixed nerves immediately produces loss of sensory perception,muscle contractions and voluntary behavior mediated by the severed distal axons.In contrast to natural regeneration(~1 mm/d)of proximal axons that may eventually reinnervate denervated targets,re-innervation is restored within minutes by PEG-fusion that consists of neurorrhaphy and a sequence of well specified hypo-and isotonic calcium-free or calcium-containing solutions,the anti-oxidant methylene blue(MB)and the membrane fusogen polyethylene glycol(PEG).In this study,we examined the relative efficacy of PEG-fusion with no MB(0%),0.5%MB,or 1%MB on the recovery of voluntary behaviors by female Sprague-Dawley rats with a complete mid-thigh severance of their sciatic nerve bathed in extracellular fluid or calcium-containing isotonic saline.The recovery of voluntary behaviors is the most relevant measure of success of any technique to repair peripheral nerve injuries.We assessed recovery by the sciatic functional index,a commonly used measure of voluntary hindlimb behaviors following complete sciatic transections.We reported that both 1%MB and 0.5%MB in sterile distilled water in our PEG-fusion protocol with neurorrhaphy significantly increased the rate and extent of behavioral recovery compared to PEG plus neurorrhaphy alone.Furthermore,0.5%MB was as effective as 1%MB in voluntary behavioral recovery as assessed by the sciatic functional index.Since sterile 1%MB is no longer clinically available,we therefore recommend that 0.5%MB be included in upcoming human clinical trials to evaluate the safety and efficacy of PEG-fusion.All animal procedures were approved by the University of Texas Institutional Animal Care and Use Committee(AUP-2019-00225)on September 9,2020.展开更多
过量的蓝光辐射会对视网膜造成损伤,损伤程度取决于眼睛接收到蓝光辐射强度。在室内空间照明中,照明距离、视线方向、光源光谱等多种因素与光辐射强度相关。为了得出照明距离和照明强度与蓝光辐射强度的关系,我们测量并计算了5000 K LE...过量的蓝光辐射会对视网膜造成损伤,损伤程度取决于眼睛接收到蓝光辐射强度。在室内空间照明中,照明距离、视线方向、光源光谱等多种因素与光辐射强度相关。为了得出照明距离和照明强度与蓝光辐射强度的关系,我们测量并计算了5000 K LED照明光源在7种不同照明强度和4种照明距离下的光谱能量分布及蓝光辐射强度。结果表明:照明强度越大或照明距离越小,人眼处的蓝光辐射强度越大;不超过3000 lx的5000 K LED照明,人坐立或站立时眼睛处的蓝光辐射强度在安全限值内。展开更多
基金Supported by National Natural Science Foundation of China(No.81900862)。
文摘AIM:To investigate the involvement of pericyte-Müller glia interaction in retinal damage repair and assess the influence of suppressing the platelet-derived growth factor receptorβ(PDGFRβ)signaling pathway in retinal pericytes on photoreceptor loss and Müller glial response.METHODS:Sprague-Dawley rats were exposed to intense light to induce retinal injury.Neutralizing antibody against PDGFRβwere deployed to block the signaling pathway in retinal pericytes through intravitreal injection.Retinal histology and Müller glial reaction were assessed following light injury.In vitro,normal and PDGFRβ-blocked retinal pericytes were cocultured with Müller cell line(rMC-1)to examine morphological and protein expression changes upon supplementation with light-injured supernatants of homogenized retinas(SHRs).RESULTS:PDGFRβblockage 24h prior to intense light exposure resulted in a significant exacerbation of photoreceptor loss.The upregulation of GFAP and p-STAT3,observed after intense light exposure,was significantly inhibited in the PDGFRβblockage group.Fur ther upregulation of cytokines monocyte chemoattractant protein 1(MCP-1)and interleukin-1β(IL-1β)was also observed following PDGFRβinhibition.In the in vitro coculture system,the addition of light-injured SHRs induced pericyte deformation and upregulation of proliferating cell nuclear antigen(PCNA)expression,while Müller cells exhibited neuron-like morphology and expressed Nestin.However,PDGFRβblockage in retinal pericytes abolished these cellular responses to light-induced damage,consistent with the in vivo PDGFRβblockage findings.CONCLUSION:Pericyte-Müller glia interaction plays a potential role in the endogenous repair process of retinal injury.Impairment of this interaction exacerbates photoreceptor degeneration in light-induced retinal injury.
基金Supported by National Natural Science Foundation of China(No.81400424)Science and Technology Research and Development Project of Shaanxi Province(No.2014K11-03-07-04)+1 种基金Innovative Talents Promotion Project of Shaanxi Province(No.2017KJXX-87)Hunan Province Education Department Outstanding Youth Science Foundation(No.15B210)
文摘In recent years, people have become increasingly attentive to light pollution influences on their eyes. In the visible spectrum, short-wave blue light with wavelength between 415 nm and 455 nm is closely related to eye light damage. This high energy blue light passes through the cornea and lens to the retina causing diseases such as dry eye, cataract, age-related macular degeneration, even stimulating the brain, inhibiting melatonin secretion, and enhancing adrenocortical hormone production, which will destroy the hormonal balance and directly affect sleep quality. Therefore, the effect of Blu-rays on ocular is becoming an important concern for the future. We describe blue light’s effects on eye tissues, summarize the research on eye injury and its physical prevention and medical treatment.
基金supported by a grant from Sichuan Province Medical Association,"SHIHUIDA"Subject,in China,No.SHD12-21the Scientific Research Project of Health Bureau of Yibin City in China
文摘Severe edema in the endoneurium can occur after non-freezing cold injury to the peripheral nerve, which suggests damage to the blood-nerve barrier. To determine the effects of cold injury on the blood-nerve barrier, the sciatic nerve on one side of Wistar rats was treated with low tem- peratures （3-5℃） for 2 hours. The contralateral sciatic nerve was used as a control. We assessed changes in the nerves using Evans blue as a fluid tracer and morphological methods. Excess fluid was found in the endoneurium 1 day after cold injury, though the tight junctions between cells remained closed. From 3 to 5 days after the cold injury, the fluid was still present, but the tight junctions were open. Less tracer leakage was found from 3 to 5 days after the cold injury compared with 1 day after injury. The cold injury resulted in a breakdown of the blood-nerve barrier func- tion, which caused endoneurial edema. However, during the early period, the breakdown of the blood-nerve barrier did not include the opening of tight junctions, but was due to other factors. Excessive fluid volume produced a large increase in the endoneurial fluid pressure, prevented liquid penetration into the endoneurium from the microvasculature. These results suggest that drug treatment to patients with cold injuries should be administered during the early period after injury because it may be more difficult for the drug to reach the injury site through the microcirculation after the tissue fluid pressure becomes elevated.
基金This work was supported by a grant from Department of Defense Peer Reviewed Orthopaedic Research Program award(grant No.OR180077 W81XWH-19-2-0054to GDB)。
文摘Complete transection of peripheral mixed nerves immediately produces loss of sensory perception,muscle contractions and voluntary behavior mediated by the severed distal axons.In contrast to natural regeneration(~1 mm/d)of proximal axons that may eventually reinnervate denervated targets,re-innervation is restored within minutes by PEG-fusion that consists of neurorrhaphy and a sequence of well specified hypo-and isotonic calcium-free or calcium-containing solutions,the anti-oxidant methylene blue(MB)and the membrane fusogen polyethylene glycol(PEG).In this study,we examined the relative efficacy of PEG-fusion with no MB(0%),0.5%MB,or 1%MB on the recovery of voluntary behaviors by female Sprague-Dawley rats with a complete mid-thigh severance of their sciatic nerve bathed in extracellular fluid or calcium-containing isotonic saline.The recovery of voluntary behaviors is the most relevant measure of success of any technique to repair peripheral nerve injuries.We assessed recovery by the sciatic functional index,a commonly used measure of voluntary hindlimb behaviors following complete sciatic transections.We reported that both 1%MB and 0.5%MB in sterile distilled water in our PEG-fusion protocol with neurorrhaphy significantly increased the rate and extent of behavioral recovery compared to PEG plus neurorrhaphy alone.Furthermore,0.5%MB was as effective as 1%MB in voluntary behavioral recovery as assessed by the sciatic functional index.Since sterile 1%MB is no longer clinically available,we therefore recommend that 0.5%MB be included in upcoming human clinical trials to evaluate the safety and efficacy of PEG-fusion.All animal procedures were approved by the University of Texas Institutional Animal Care and Use Committee(AUP-2019-00225)on September 9,2020.
文摘过量的蓝光辐射会对视网膜造成损伤,损伤程度取决于眼睛接收到蓝光辐射强度。在室内空间照明中,照明距离、视线方向、光源光谱等多种因素与光辐射强度相关。为了得出照明距离和照明强度与蓝光辐射强度的关系,我们测量并计算了5000 K LED照明光源在7种不同照明强度和4种照明距离下的光谱能量分布及蓝光辐射强度。结果表明:照明强度越大或照明距离越小,人眼处的蓝光辐射强度越大;不超过3000 lx的5000 K LED照明,人坐立或站立时眼睛处的蓝光辐射强度在安全限值内。
