Intravenous bone marrow mononuclear cells transplantation in aged mice increases transcription of glucose transporter 1 and Na+/K+-ATPase at hippocampus followed by restored neurological functions

We recently reported that intravenous bone marrow mononuclear cell (BM-MNC) transplantation in stroke improves neurological function through improvement of cerebral metabolism. Cerebral metabolism is known to diminish with aging, and the reduction of metabolism is one of the presumed causes of neurological decline in the elderly. We report herein that transcription of glucose transporters, monocarboxylate transporters, and Na+/K+-ATPase is downregulated in the hippocampus of aged mice with impaired neurological functions. Intravenous BM-MNC transplantation in aged mice stimulated the transcription of glucose transporter 1 and Na+/K+-ATPase α1 followed by restoration of neurological function. As glucose transporters and Na+/K+-ATPases are closely related to cerebral metabolism and neurological function, our data indicate that BM-MNC transplantation in aged mice has the potential to restore neurological function by activating transcription of glucose transporter and Na+/K+-ATPase. Furthermore, our data indicate that changes in transcription of glucose transporter and Na+/K+-ATPase could be surrogate biomarkers for age-related neurological impairment as well as quantifying the efficacy of therapies

Gap junction-mediated cell-cell interaction between transplanted mesenchymal stem cells and vascular endothelium in stroke

We have shown previously that transplanted bone marrow mononuclear cells (BM‐MNC), which are a cell fraction rich in hematopoietic stem cells, can activate cerebral endothelial cells via gap junction‐mediated cell‐cell interaction. In the present study, we investigated such cell‐cell interaction between mesenchymal stem cells (MSC) and cerebral endothelial cells. In contrast to BM‐MNC, for MSC we observed suppression of vascular endothelial growth factor uptake into endothelial cells and transfer of glucose from endothelial cells to MSC in vitro. The transfer of such a small molecule from MSC to vascular endothelium was subsequently confirmed in vivo and was followed by suppressed activation of macrophage/microglia in stroke mice. The suppressive effect was absent by blockade of gap junction at MSC. Furthermore, gap junction‐mediated cell‐cell interaction was observed between circulating white blood cells and MSC. Our findings indicate that gap junction‐mediated cell‐cell interaction is one of the major pathways for MSC‐mediated suppression of inflammation in the brain following stroke and provides a novel strategy to maintain the blood‐brain barrier in injured brain. Furthermore, our current results have the potential to provide a novel insight for other ongoing clinical trials that make use of MSC transplantation aiming to suppress excess inflammation, as well as other diseases such as COVID‐19 (coronavirus disease 2019)

Increased RNA transcription of energy source transporters in circulating white blood cells of aged mice

Circulating white blood cells (WBC) contribute toward maintenance of cerebral metabolism and brain function. Recently, we showed that during aging, transcription of metabolism related genes, including energy source transports, in the brain significantly decreased at the hippocampus resulting in impaired neurological functions. In this article, we investigated the changes in RNA transcription of metabolism related genes (glucose transporter 1 [Glut1], Glut3, monocarboxylate transporter 4 [MCT4], hypoxia inducible factor 1-α [Hif1-α], prolyl hydroxylase 3 [PHD3] and pyruvate dehydrogenase kinase 1 [PDK1]) in circulating WBC and correlated these with brain function in mice. Contrary to our expectations, most of these metabolism related genes in circulating WBC significantly increased in aged mice, and correlation between their increased RNA transcription and impaired neurological functions was observed. Bone marrow mononuclear transplantation into aged mice decreased metabolism related genes in WBC with accelerated neurogenesis in the hippocampus. In vitro analysis revealed that cell-cell interaction between WBC and endothelial cells via gap junction is impaired with aging, and blockade of the interaction increased their transcription in WBC. Our findings indicate that gross analysis of RNA transcription of metabolism related genes in circulating WBC has the potential to provide significant information relating to impaired cell-cell interaction between WBC and endothelial cells of aged mice. Additionally, this can serve as a tool to evaluate the change of the cell-cell interaction caused by various treatments or diseases

Clot-derived contaminants in transplanted bone marrow mononuclear cells impair the therapeutic effect in stroke

Background and Purpose— The beneficial effects of bone marrow mononuclear cell (BM-MNC) transplantation in preclinical experimental stroke have been reliably demonstrated. However, only overall modest effects in clinical trials were observed. We have investigated and reported a cause of the discrepancy between the preclinical and clinical studies. Methods— To investigate the possible cause of low efficacy of BM-MNC transplantation in experimental stroke, we have focused on blood clot formation, which is not uncommon in human bone marrow aspirates. To evaluate the effects of clot-derived contaminants in transplanted BM-MNC on stroke outcome, a murine stroke model was used. Results— We show that BM-MNC separated by an automatic cell isolator (Sepax2), which does not have the ability to remove clots, did not attenuate brain atrophy after stroke. In contrast, manually isolated, clot-free BM-MNC exerted therapeutic effects. Clot-derived contaminants were also transplanted intravenously to poststroke mice. We found that the transplanted contaminants were trapped at the peristroke area, which were associated with microglial/macrophage activation. Conclusions— Clot-derived contaminants in transplanted BM-MNC nullify therapeutic effects in experimental stroke. This may explain neutral results in clinical trials, especially in those using automated stem cell separators that lack the ability to remove clot-derived contaminants. Visual Overview— An online visual overview is available for this article

Phase II Study of Irinotecan plus S-1 Combination for Previously Untreated Advanced Non-Small Cell Lung Cancer: Hokkaido Lung Cancer Clinical Study Group Trial (HOT) 0601

Objective: Platinum-free regimens can represent an alternative for advanced non-small cell lung cancer (NSCLC) if similar efficacy is provided with better tolerability. This study evaluated the efficacy and safety of combined irinotecan and S-1 for chemotherapy-naïve advanced NSCLC. Methods: Chemotherapy consisted of 4-week cycles of intravenous irinotecan (100 mg/m2, days 1 and 15) and oral S-1 (80 mg/m2, days 1-14). The primary endpoint was response rate, while secondary endpoints were overall survival (OS), progression-free survival (PFS), and safety. Results: A total of 112 cycles was administered to 40 patients (median, 3 cycles; range 1-6 cycles). Twelve patients showed partial response (PR) and 17 patients exhibited stable disease (SD), representing a response rate of 30% and a disease control rate of 72.5%. Median survival time and median PFS were 16.1 months and 4.8 months, respectively. Hematological toxicities of grade 3 or 4 were neutropenia (32.5%) and anemia (5.0%). The most common non-hematological toxicities of grade 3 or 4 included diarrhea (15.0%) and anorexia (17.5%). Patients homo- or heterozygous for UGTA1A*6 tended to show a higher incidence of grade 3 diarrhea (p = 0.055). Conclusion: The combination of irinotecan and S-1 offers good efficacy and tolerability for previously untreated advanced NSCLC