monocular-visual-deprivation-ocular-dominance-plasticity-measurement

Monocular Visual Deprivation and Ocular Dominance Plasticity Measurement in the Mouse Primary Visual Cortex

Monocular visual deprivation is an excellent experimental paradigm to induce primary visual cortical response plasticity. In general, the response of the ...

University of electronic science and technology of China

University of Electronic Science and Technology of China

Although surgery and high‑dose radiotherapy have been the standard treatments for glioblastoma multiforme (GBM), these therapies are palliative, due to the high risk of local relapse. Emerging evidence has demonstrated that DNA double‑strand break (DSB) repair serves a critical role in resistance to radiotherapy. Previous studies have revealed that mangiferin possesses anti‑neoplastic effects on human lung adenocarcinoma and ovarian cancer. The present study aimed to investigate the role of mangiferin in radio‑sensitivity inhuman GBM. Through in vitro experiments, decreased proliferation and increased DNA damage were observed in cells pretreated with mangiferin following radiation. Further study of the repair pathway indicated that mangiferin inhibits the non‑homologous end‑joining (NHEJ) DSB repair pathway. Furthermore, studies on key proteins in the NHEJ DSB repair pathway revealed that mangiferin inhibited the phosphorylation of serine‑protein kinase ATM, TP53‑binding protein 1 and γ‑histone H2AX (γ‑H2AX). In addition, observations on the average percentages of γ‑H2AX‑positive cells and the average number of γ‑H2AX foci per cell suggested that treatment with mangiferin decreased the number of γ‑H2AX foci in GBM cells following radiation. However, mangiferin selectively inhibited DSB repair in GBM cells, and was not able to trigger DSB repair inhibition in normal neuronal Schwann cells. Through in vivo tumor‑bearing mouse experiments, a smaller tumor volume, decreased tumor weight and prolonged life span were observed in mice treated with mangiferin following radiation. Therefore, xenograft GBM models clearly demonstrated that treatment with mangiferin treatment may increase tumor sensitivity to radiotherapy. Taken together, as demonstrated by in vivo and in vitro data, mangiferin may be a potential novel therapeutic drug for improving the radiation sensitivity of glioblastoma.

Mangiferin induces radiosensitization in glioblastoma cells by inhibiting nonhomologous end joining.

Organ transplantation is a crucial medical procedure, as it is often the only treatment for patients suffering from end-stage organ failure. Unfortunately, the shortage of donor organs limits the number of patients whose lives can be saved. Carrying out research on xenotransplantation with the aim of eventually replacing human organ transplants with those of animals is very promising, as it could effectively bridge the shortfall in donor organs. Thanks to the success of cloned pigs and to the emergence of gene-editing techniques, genetically modified pigs have come to be considered ideal animal donors for human xenotransplantation and have been widely used in basic research. Such research focuses on pig-to-nonhuman primates transplantation, as the recipients are suitable for preclinical studies because both their genes and organ sizes are similar to those of humans. Chinese transplantation scientists have carried out several experiments on Tibetan macaques, including successful preclinical transplants of material from genetically modified pigs, as well as research on such topics as intraocular pressure, Parkinson's disease, advanced cancer, islet transplantation, and liver transplantation. This article reviews basic and applied research on Tibetan macaques in xenotransplantation, as well as the issues of immune rejection and ethical concerns. We aim to demonstrate the various advantages of Tibetan macaques as transplant recipients compared to other nonhuman primate species and to provide a perspective for the future establishment of Tibetan macaques as principal recipients in preclinical studies of xenotransplantation.

Promising potentials of Tibetan macaques in xenotransplantation.

Pig-to-human organ transplantation provides an alternative for critical shortage of human organs worldwide. Genetically modified pigs are promising donors for xenotransplantation as they show many anatomical and physiological similarities to humans. However, immunological rejection including hyperacute rejection (HAR), acute humoral xenograft rejection (AHXR), immune cell-mediated rejection, and other barriers associated with xenotransplantation must be overcome with various strategies for the genetic modification of pigs. In this review, we summarize the outcomes of genetically modified and cloned pigs achieved by Chinese scientists to resolve the above-mentioned problems in xenotransplantation. It is now possible to knockout several porcine genes associated with the expression of sugar residues, antigens for (naturally) existing antibodies in humans, including GGTA1, CMAH, and β4GalNT2, and thereby preventing the antigen-antibody response. Moreover, insertion of human complement- and coagulation-regulatory transgenes, such as CD46, CD55, CD59, and hTBM, can further overcome effects of the humoral immune response and coagulation dysfunction, while expression of regulatory factors of immune responses can inhibit the adaptive immune rejection. Furthermore, transgenic strategies have been developed by Chinese scientists to reduce the potential risk of infections by endogenous porcine retroviruses (PERVs). Breeding of multi-gene low-immunogenicity pigs in China is also presented in this review. Lastly, we will briefly mention the preclinical studies on pig-to-non-human primate xenotransplantation conducted in several centers in China.

Progress in multiple genetically modified minipigs for xenotransplantation in China.

Necroptosis is a type of programmed cell death with necrotic morphology, occurring in a variety of biological processes, including inflammation, immune response, embryonic development and metabolic abnormalities. The current nomenclature defines necroptosis as cell death mediated by signal transduction from receptor‑interacting serine/threonine kinase (RIP) 1 to RIP3 (hereafter called RIP1/RIP3). However, RIP3‑dependent cell death would be a more precise definition of necroptosis. RIP3 is indispensable for necroptosis, while RIP1 is not consistently involved in the signal transduction. Notably, deletion of RIP1 even promotes RIP3‑mediated necroptosis under certain conditions. Necroptosis was previously thought as an alternate process of cell death in case of apoptosis inhibition. Currently, necroptosis is recognized to serve a pivotal role in regulating various physiological processes. Of note, it mediates a variety of human diseases, such as ischemic brain injury, immune system disorders and cancer. Targeting and inhibiting necroptosis, therefore, has the potential to be used for therapeutic purposes. To date, research has elucidated the suppression of RIP1/RIP3 via effective inhibitors and highlighted their potential application in disease therapy. The present review focused on the molecular mechanisms of RIP1/RIP3‑mediated necroptosis, explored the functions of RIP1/RIP3 in necroptosis, discussed their potential as a novel therapeutic target for disease therapy, and provided valuable suggestions for further study in this field.

Ting Liu

The Clinical Hospital of Chengdu Brain Science Institute,
MOE Key Lab for NeuroInformation,
The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for NeuroInformation

University of electronic science and technology of China

Monocular Visual Deprivation and Ocular Dominance Plasticity Measurement in the Mouse Primary Visual Cortex

Ting Liu

The Clinical Hospital of Chengdu Brain Science Institute,MOE Key Lab for NeuroInformation,The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for NeuroInformation

University of electronic science and technology of China

Monocular Visual Deprivation and Ocular Dominance Plasticity Measurement in the Mouse Primary Visual Cortex

The Clinical Hospital of Chengdu Brain Science Institute,
MOE Key Lab for NeuroInformation,
The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for NeuroInformation