scholarly journals Regulation of Reentrainment Function Is Dependent on a Certain Minimal Number of Intact Functional ipRGCs in rd Mice

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Jingxue Zhang ◽  
Huaizhou Wang ◽  
Shen Wu ◽  
Qian Liu ◽  
Ningli Wang

Purpose. To investigate the effect of partial ablation of melanopsin-containing retinal ganglion cells (mcRGCs) on nonimage-forming (NIF) visual functions in rd mice lacking rods.Methods. The rd mice were intravitreally injected with different doses (100 ng/μl, 200 ng/μl, and 400 ng/μl) of immunotoxin melanopsin-SAP. And then, the density of ipRGCs was examined. After establishing the animal models with different degrees of ipRGC damage, a wheel-running system was used to evaluate their reentrainment response.Results. Intravitreal injection of melanopsin-SAP led to partial ablation of ipRGCs in a dose-dependent manner. The survival rates of ipRGCs in the 100 ng/μl, 200 ng/μl, and 400 ng/μl groups were 74.14% ± 4.15%, 39.25% ± 2.29%, and 38.38% ± 3.74%, respectively. The wheel-running experiments showed that more severe ipRGC loss was associated with a longer time needed for reentrainment. When the light/dark cycle was delayed by 8 h, the rd mice in the PBS control group took 4.67 ± 0.79 days to complete the synchronization with the shifted cycle, while those in the 100 ng/μl and 200 ng/μl groups required 7.90 ± 0.55 days and 11.00 ± 0.79 days to complete the synchronization with the new light/dark cycle, respectively.Conclusion. Our study indicates that the regulation of some NIF visual functions is dependent on a certain minimal number of intact functional ipRGCs.

2011 ◽  
Vol 300 (2) ◽  
pp. E392-E401 ◽  
Author(s):  
Gregory J. Morton ◽  
Karl J. Kaiyala ◽  
Jonathan D. Fisher ◽  
Kayoko Ogimoto ◽  
Michael W. Schwartz ◽  
...  

Mechanisms regulating spontaneous physical activity remain poorly characterized despite evidence of influential genetic and acquired factors. We evaluated ambulatory activity and wheel running in leptin-deficient ob/ob mice and in wild-type mice rendered hypoleptinemic by fasting in both the presence and absence of subcutaneous leptin administration. In ob/ob mice, leptin treatment to plasma levels characteristic of wild-type mice acutely increased both ambulatory activity (by 4,000 ± 200 beam breaks/dark cycle, P < 0.05) and total energy expenditure (TEE; by 0.11 ± 0.01 kcal/h during the dark cycle, P < 0.05) in a dose-dependent manner and acutely increased wheel running (+350%, P < 0.05). Fasting potently increased ambulatory activity and wheel running in wild-type mice (AA: +25%, P < 0.05; wheel running: +80%, P < 0.05), and the effect of fasting was more pronounced in ob/ob mice (AA: +400%, P < 0.05; wheel running: +1,600%, P < 0.05). However, unlike what occurred in ad libitum-fed ob/ob mice, physiological leptin replacement attenuated or prevented fasting-induced increases of ambulatory activity and wheel running in both wild-type and ob/ob mice. Thus, plasma leptin is a physiological regulator of spontaneous physical activity, but the nature of leptin's effect on activity is dependent on food availability.


Cells ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 677 ◽  
Author(s):  
Ning Yang ◽  
Brent K Young ◽  
Ping Wang ◽  
Ning Tian

Retinal ganglion cell (RGC) death occurs in many eye diseases, such as glaucoma and traumatic optic neuropathy (TON). Increasing evidence suggests that the susceptibility of RGCs varies to different diseases in an RGC type-dependent manner. We previously showed that the susceptibility of several genetically identified RGC types to N-methyl-D-aspartate (NMDA) excitotoxicity differs significantly. In this study, we characterize the susceptibility of the same RGC types to optic nerve crush (ONC). We show that the susceptibility of these RGC types to ONC varies significantly, in which BD-RGCs are the most resistant RGC type while W3-RGCs are the most sensitive cells to ONC. We also show that the survival rates of BD-RGCs and J-RGCs after ONC are significantly higher than their survival rates after NMDA excitotoxicity. These results are consistent with the conclusion that the susceptibility of RGCs to ONC varies in an RGC type-dependent manner. Further, the susceptibilities of the same types of RGCs to ONC and NMDA excitotoxicity are significantly different. These are valuable insights for understanding of the selective susceptibility of RGCs to various pathological insults and the development of a strategy to protect RGCs from death in disease conditions.


2017 ◽  
Vol 44 (4) ◽  
pp. 1411-1424 ◽  
Author(s):  
Wolfram Eichler ◽  
Helena Savković-Cvijić ◽  
Susanne Bürger ◽  
Mike Beck ◽  
Manuela Schmidt ◽  
...  

Background/ Aims: This study was performed to reveal signaling pathways exploited by pigment epithelium-derived factor (PEDF) derived from retinal (glial) Müller cells to protect retinal ganglion cells (RGCs) from cell death. Methods: The survival of RGCs was determined in the presence of conditioned culture media (MCM) from or in co-cultures with Müller cells. The significance of PEDF-induced STAT3 activation was evaluated in viability assays and using Western blotting analyses and siRNA-transfected cells. Results: Secreted mediators of Müller cells increased survival of RGCs under normoxia or hypoxia to a similar degree as of PEDF- or IL-6-exposed cells. PEDF and MCM induced an increased STAT3 activation in RGCs and R28 cells, and neutralization of PEDF in MCM attenuated STAT3 activation. Inhibition of STAT3 reduced PEDF-promoted survival of RGCs. Similar to IL-6, PEDF induced STAT3 activation, acting in a dose-dependent manner via the PEDF receptor (PEDF-R) encoded by the PNPLA2 gene. Ablation of PEDF-R attenuated MCM-induced STAT3 activation and compromised the viability of PEDF-exposed R28 cells. Conclusions: Müller cells are an important source of PEDF, which promotes RGC survival through STAT3 activation and, at least in part, via PEDF-R. Enhancing the secretory function of Müller cells may be useful to promote RGC survival in retinal neurodegenerative diseases.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xuewen Wu ◽  
Li Zhang ◽  
Yihui Li ◽  
Wenjuan Zhang ◽  
Jianjun Wang ◽  
...  

AbstractMutations in voltage-gated potassium channel KCNE1 cause Jervell and Lange-Nielsen syndrome type 2 (JLNS2), resulting in congenital deafness and vestibular dysfunction. We conducted gene therapy by injecting viral vectors using the canalostomy approach in Kcne1−/− mice to treat both the hearing and vestibular symptoms. Results showed early treatment prevented collapse of the Reissner’s membrane and vestibular wall, retained the normal size of the semicircular canals, and prevented the degeneration of inner ear cells. In a dose-dependent manner, the treatment preserved auditory (16 out of 20 mice) and vestibular (20/20) functions in mice treated with the high-dosage for at least five months. In the low-dosage group, a subgroup of mice (13/20) showed improvements only in the vestibular functions. Results supported that highly efficient transduction is one of the key factors for achieving the efficacy and maintaining the long-term therapeutic effect. Secondary outcomes of treatment included improved birth and litter survival rates. Our results demonstrated that gene therapy via the canalostomy approach, which has been considered to be one of the more feasible delivery methods for human inner ear gene therapy, preserved auditory and vestibular functions in a dose-dependent manner in a mouse model of JLNS2.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 386
Author(s):  
Tung-Hu Tsai ◽  
Yu-Jen Chen ◽  
Li-Ying Wang ◽  
Chen-Hsi Hsieh

This study was performed to evaluate the interaction between conventional or high-dose radiotherapy (RT) and the pharmacokinetics (PK) of regorafenib in concurrent or sequential regimens for the treatment of hepatocellular carcinoma. Concurrent and sequential in vitro and in vivo studies of irradiation and regorafenib were designed. The interactions of RT and regorafenib in vitro were examined in the human hepatoma Huh-7, HA22T and Hep G2 cell lines. The RT–PK phenomenon and biodistribution of regorafenib under RT were confirmed in a free-moving rat model. Regorafenib inhibited the viability of Huh-7 cells in a dose-dependent manner. Apoptosis in Huh-7 cells was enhanced by RT followed by regorafenib treatment. In the concurrent regimen, RT decreased the area under the concentration versus time curve (AUC)regorafenib by 74% (p = 0.001) in the RT2 Gy × 3 fraction (f’x) group and by 69% (p = 0.001) in the RT9 Gy × 3 f’x group. The AUCregorafenib was increased by 182.8% (p = 0.011) in the sequential RT2Gy × 1 f’x group and by 213.2% (p = 0.016) in the sequential RT9Gy × 1 f’x group. Both concurrent regimens, RT2Gy × 3 f’x and RT9Gy × 3 f’x, clearly decreased the biodistribution of regorafenib in the heart, liver, lung, spleen and kidneys, compared to the control (regorafenib × 3 d) group. The concurrent regimens, both RT2Gy × 3 f’x and RT9Gy × 3 f’x, significantly decreased the biodistribution of regorafenib, compared with the control group. The PK of regorafenib can be modulated both by off-target irradiation and stereotactic body radiation therapy (SBRT).


2020 ◽  
Vol 63 (1) ◽  
Author(s):  
Guili Bao ◽  
Yinglong Zhang ◽  
Xiaoguang Yang

AbstractIn this study, lemon peel flavonoids (LPF) were administered to investigate its effect on the anti-fatigue and antioxidant capacity of mice that undergo exercise until exhaustion. LPF (88.36 min in LPFH group mice) significantly increased the exhaustion swimming time compare to the untreated mice (40.36 min), increased the liver glycogen and free fatty acid content in mice and reduce lactic acid and BUN content in a dose-dependent manner. As the concentration of lemon peel flavonoids increased, the serum creatine kinase, aspartate aminotransferase, and alanine aminotransferase levels of mice gradually decreased. LPF increases superoxide dismutase (SOD) and catalase (CAT) levels in mice and reduces malondialdehyde levels in a dose-dependent manner. And LPF raises hepatic tissue SOD, CAT activities and reduces skeletal muscle tissue iNOS, TNF-α levels of mice compared to the control group. LPF also enhanced the expression of copper/zinc-superoxide dismutase (Cu/Zn-SOD), manganese-superoxide dismutase (Mn-SOD), and CAT mRNA in mouse liver tissue. LPF also enhanced the expression of alanine/serine/cysteine/threonine transporter 1 (ASCT1) mRNA and attenuate the expression of syncytin-1, inducible nitric oxide synthase (iNOS), and tumor necrosis factor (TNF)-α in mouse skeletal muscle. According to high-performance liquid chromatography (HPLC) analysis, it was found that LPF contains flavonoids such as rutin, astragalin, isomangiferin, naringin, and quercetin. Our experimental data show that LPF has good anti-fatigue effects and anti-oxidation ability. In summary, LPF has high prospects to be developed and added to nutritional supplements.


2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Yuhong Fu ◽  
Ying Wang ◽  
Xinyuan Gao ◽  
Huiyao Li ◽  
Yue Yuan

Background. Diabetic retinopathy (DR) is a severe complication of diabetes mellitus. DR is considered as a neurovascular disease. Retinal ganglion cell (RGC) loss plays an important role in the vision function disorder of diabetic patients. Histone deacetylase3 (HDAC3) is closely related to injury repair and nerve regeneration. The correlation between HDAC3 and retinal ganglion cells in diabetic retinopathy is still unclear yet. Methods. To investigate the chronological sequence of the abnormalities of retinal ganglion cells in diabetic retinopathy, we choose 15 male db/db mice (aged 8 weeks, 12 weeks, 16 weeks, 18 weeks, and 25 weeks; each group had 3 mice) as diabetic groups and 3 male db/m mice (aged 8 weeks) as the control group. In this study, we examined the morphological and immunohistochemical changes of HDAC3, Caspase3, and LC3B in a sequential manner by characterizing the process of retinal ganglion cell variation. Results. Blood glucose levels and body weights of db/db mice were significantly higher than that of the control group, P<0.01. Compared with the control group, the number of retinal ganglion cells decreased with the duration of disease increasing. HDAC3 expression gradually increased in RGCs of db/db mice. Caspase3 expression gradually accelerated in RGCs of db/db mice. LC3B expression dynamically changed in RGCs of db/db mice. HDAC3 was positively correlated with Caspase3 expression (r=0.7424), P<0.01. HDAC3 was positively correlated with LC3B expression (r=0.7336), P<0.01. Discussion. We clarified the dynamic expression changes of HDAC3, Caspase3, and LC3B in retinal ganglion cells of db/db mice. Our results suggest the HDAC3 expression has a positive correlation with apoptosis and autophagy.


2010 ◽  
Vol 30 (7) ◽  
pp. 591-602 ◽  
Author(s):  
Abdul Basir ◽  
Ahrar Khan ◽  
Riaz Mustafa ◽  
Muhammad Zargham Khan ◽  
Farzana Rizvi ◽  
...  

The aim of this study was to investigate effects of lambda-cyhalothrin (LCT) on clinical, hematological, biochemical and pathological alterations in rabbits (Oryctolagus cuniculus). New Zealand white female rabbits (n = 24) of 4-5 months age having 997.92 ± 32.83 g weight were divided into four equal groups. Group A (control) received normal saline intraperitoneally (ip). Animals in groups B, C and D were treated with LCT 1.0, 4.0 and 8.0 mg/kg bw ip. Each group received seven consecutive doses at an interval of 48 hours. Blood and serum samples were collected at an interval of 96 hours. Blood analysis revealed a significant (p < 0.05) decrease in red blood cell and white blood cell counts, hemoglobin concentration and lymphocytes, while mean corpuscular hemoglobin concentration, mean corpuscular volume, neutrophils, monocytes and eosinophils were increased. Serum biochemical analysis revealed significant (p < 0.05) decrease in serum total proteins and serum albumin, while an increase was seen in serum alanine aminotransferase and aspartate aminotransferase activities compared with the control group. Serum globulin values varied non-significantly in all treatment groups as compared to control group. A dose-dependent increase in the incidence of micronucleated polychromatic erythrocyte was observed. All gross and histopathological lesions observed in LCT-treated rabbits were dose-dependent. Liver of the treated rabbits exhibited extensive perihepatitis, hyperplasia of bile duct, necrosis, hemorrhages and congestion. In lungs, there were hemorrhages, thickened alveolar walls, congestion, emphysema, collapsed alveoli and accumulation of extensive inflammatory cells. Kidneys were congested and hemorrhagic whereas renal parenchyma and stroma were normal. Microscopically, heart showed congestion of blood vessels and nuclear pyknosis, myodegeneration. It was concluded from the study that LCT produced toxicopathological alterations in rabbits in a dose-dependent manner. On the basis of the results, it can be suggested that overdosing of LCT be avoided while treating animals for ectoparasites.


2022 ◽  
Vol 12 (3) ◽  
pp. 506-513
Author(s):  
Ying Lv ◽  
Liyan Ye ◽  
Xiujuan Zheng

This study aimed to explore the role of ATI-2341 in Asherman’s syndrome and its impact on menstrual blood-derived mesenchymal stem cells (MenSCs). Following establishment of endometrial injury model, MenSCs were extracted from rats and cultured. They were treated with ATI-2341 TFA at different concentrations (10 ng/mL, 50 ng/mL, 100 ng/mL) and MenSCs treated without ATI-2341 TFA were taken as controls. Flow cytometry was conducted to detect the cell cycle. MTT was carried out to evaluate proliferation of endometrial cells. The expression levels of MMP-9, TIMP-1, CK, and VIM were determined with staining used to reflect morphology of endometrium. Administration with ATI-2341 TFA resulted in decreased expression of MMP-9 and increased expression of TIMP-1 in a dose-dependent manner. Of note, the increase of ATI-2341 TFA concentration was accompanied with elevated cell proliferation rate, increased number of glands in the endometrium, and decreased fibrosis area. As treated with 100 ng/mL ATI-2341 TFA, the cells exhibited more glands than that under other concentrations with uniformly arranged glands and lowest expression levels of CK and VIM, control group had plenty of blue-stained collagen fibers in the intima and least amount of glands. ATI-2341 TFA 100 ng/mL induced endometrial epithelial recruitment effect on MenSCs and promoted endometrial repair more significantly than Gi-3 pathway agonists. Collectively, ATI-2341 TFA enhances MenSC recruitment and facilitates endometrial epithelial cells proliferation and the repair of uterine damage in Asherman’s syndrome through Gi pathway. These findings provide a\ novel insight into the MenSC-based treatment against Asherman’s syndrome and deserve further investigation.


Author(s):  
SAMBIT KUMAR SAHOO ◽  
STHITAPRAGNYA PANDA

Objective: The objective of the study was to evaluate the antinociceptive effect of Raphanus sativus Linn. using Randall Selitto method. Methods: Streptozotocin, lard, casein, cholesterol, DL-methionine, yeast powder, quercetin, thiobarbituric acid, 2-nitrobenzoic acid (5, 5, Dithiobis), hematoxylin, and hydrogen peroxide were used. A diet rich in fat content was fed to the animals for a period of 2 weeks. After a stabilization period of 2weeks, the treatment period started and continued for a period of 8weeks. The nociceptive parameters were assessed once a week by Randall Selitto method and hot plate test. After treatment, the animals were sacrificed, and antioxidant parameters were assessed using sciatic nerve homogenate and histopathological analysis of sciatic nerve. Results: Treatment R. sativus extract (RSE 100 mg/kg and 200 mg/kg) appreciably declined the levels of blood glucose in a dose-dependent manner, and it was comparable with standard quercetin. A significant increase in pain threshold levels was observed by the treatment RSE in hot plate method after the 4th week compared to diabetic control, and it was consistent until the end of treatment (p<0.01, p<0.001). In Randall Selitto method RSE produced a significant increase in paw withdrawal threshold after the 4th week compared to diabetic control, and it was consistently increased until the end of treatment. RSE (100 and 200 mg/kg) significantly restored the levels of antioxidant enzymes and decreased lipid peroxidation in a dose-dependent fashion in comparison with the diabetic control group. RSE (100 mg/kg and 200 mg/kg) attenuated the nerve degeneration and axonal swelling along with quercetin. Conclusion: The findings from the current study showed the antinociceptive and antioxidant effect of R. sativus in neuropathic pain in diabetes.


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