Ischemia/reperfusion (I/R) injury is the main cause of primary graft dysfunction of liver allografts. Cobalt-protoporphyrin (CoPP)–dependent induction of heme oxygenase (HO)-1 has been shown to protect the liver from I/R injury. This study analyzes the apoptotic mechanisms of HO-1-mediated cytoprotection in mouse liver exposed to I/R injury. HO-1 induction was achieved by the administration of CoPP (1.5 mg/kg body weight i.p.). Mice were studied in in vivo model of hepatic segmental (70 %) ischemia for 60 min and reperfusion injury. Mice were randomly allocated to four main experimental groups (n = 10 each): (1) A control group undergoing sham operation. (2) Similar to group 1 but with the administration of CoPP 72 h before the operation. (3) Mice undergoing in vivo hepatic I/R. (4) Similar to group 3 but with the administration of CoPP 72 h before ischemia induction. When compared with the I/R mice group, in the I/R+CoPP mice group, the increased hepatic expression of HO-1 was associated with a significant reduction in liver enzyme levels, fewer apoptotic hepatocytes cells were identified by morphological criteria and by immunohistochemistry for caspase-3, there was a decreased mean number of proliferating cells (positively stained for Ki67), and a reduced hepatic expression of: C/EBP homologous protein (an index of endoplasmic reticulum stress), the NF-κB’s regulated genes (CIAP2, MCP-1 and IL-6), and increased hepatic expression of IκBa (the inhibitory protein of NF-κB). HO-1 over-expression plays a pivotal role in reducing the hepatic apoptotic IR injury. HO-1 may serve as a potential target for therapeutic intervention in hepatic I/R injury during liver transplantation.
Human cerebral organoids resemble the 3D complexity of the human brain and have the potential to augment current drug development pipelines for neurological disease. Epilepsy is a complex neurological condition characterized by recurrent seizures. A third of people with epilepsy do not respond to currently available pharmaceutical drugs, and there is not one drug that treats all subtypes; thus, better models of epilepsy are needed for drug development. Cerebral organoids may be used to address this unmet need. In the present work, human cerebral organoids are used along with electrophysiological methods to explore oxygen-glucose deprivation as a hyperexcitability agent. This activity is investigated in its response to current antiseizure drugs. Furthermore, the mechanism of action of the drug candidates is probed with qPCR and immunofluorescence. The findings demonstrate OGD-induced hyperexcitable changes in the cerebral organoid tissue, which is treated with cannabidiol and bumetanide. There is evidence for NKCC1 and KCC2 gene expression, as well as other genes and proteins involved in the complex development of GABAergic signaling. This study supports the use of organoids as a platform for modelling cerebral cortical hyperexcitability that could be extended to modelling epilepsy and used for drug discovery.
Pericytes are mural cells on the abluminal surface of capillaries that play an essential role in capillary stabilization. They also regulate angiogenesis by guiding vessel sprouting and the maturation of newly formed sprouts. Furthermore, pericytes may have adipogenic differentiation potential. Muscle ischemia, as seen in peripheral artery disease, causes oxidative and nutrient‐deprivation stress and ultimately death of skeletal myocytes. Ischemia is a stimulus for angiogenesis, a crucial process for muscle regeneration. However, newly formed capillaries are structurally and functionally aberrant, which might be explained by dysfunction of pericytes. Recently, we showed that high‐fat (HF) diet in mice provokes a shift in skeletal muscle pericytes towards a pre‐adipocyte phenotype. This alteration may disrupt capillary remodeling processes and contribute to the worsened prognosis of PAD patients with diabetes. Thus, the purpose of this study was to assess the effects of HF diet and ischemia on skeletal muscle pericytes. We hypothesized that the number of capillary‐associated pericytes will be altered by each HF diet and ischemia and together, they may exert an additive effect. Two groups of 8 weeks old NG2/DsRed mice (that express DsRed protein under the control of the pericyte NG2 promoter) were fed normal (NC) or high fat (HF) diets (10% or 60% kcal from fat, respectively) for two weeks. The second group also underwent unilateral femoral artery ligation surgery to induce ischemia and were euthanized 14 days post‐ischemia. Analysis of EDL muscle longitudinal sections showed that HF diet decreased pericyte number/100 μm2 vascular area (30.1 ± 0.6 (n=5) vs. 23.1 ± 2.4 (n=6) in NC and HF, respectively p<0.05). PDGFRβ+ pericytes isolated from the muscles of these mice exhibited a HF diet‐induced increase in the relative mRNA levels of leptin (0.51 ± 0.11 (n=7) vs. 0.83 ± 0.16 (n=6) in NC and HF, respectively p<0.05) and the pre‐adipocyte commitment marker Zfp423 (0.92 ± 0.11 (n=7) vs. 1.10 ± 0.14 (n=7) in NC and HF, respectively p<0.05), suggesting a shift in pericyte phenotype. Ischemic muscles of both NC and HF‐fed mice had increased numbers of capillary‐associated pericytes compared to non‐ischemic muscle (1.6 ± 0.4 and 1.4 ± 0.1fold increases in NC and HF, respectively. n=3, p<0.05). Capillary area relative to muscle area did not differ with diet or ischemia. These samples will be used to quantify pericyte proliferation and markers of pericyte phenotype in the ischemic muscles. These data provide a valuable first step in defining the behavior and functions of pericytes during muscle adaptations to the pathophysiological conditions of HF diet and ischemia.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.