MELAS-Derived Neurons Functionally Improve by Mitochondrial Transfer from Highly Purified Mesenchymal Stem Cells (REC).

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episode (MELAS) syndrome, caused by a single base substitution in mitochondrial DNA (m.3243A>G), is one of the most common maternally inherited mitochondrial diseases accompanied by neuronal damage due to defects in the oxidative phosphorylation system. There is no established treatment. Our previous study reported a superior restoration of mitochondrial function and bioenergetics in mitochondria-deficient cells using highly purified mesenchymal stem cells (RECs). However, whether such exogenous mitochondrial donation occurs in mitochondrial disease models and whether it plays a role in the recovery of pathological neuronal functions is unknown. Here, utilizing induced pluripotent stem cells (iPSC), we differentiated neurons with impaired mitochondrial function from patients with MELAS. MELAS neurons and RECs/mesenchymal stem cells (MSCs) were cultured under contact or non-contact conditions. Both RECs and MSCs can donate mitochondria to MELAS neurons, but RECs are more excellent than MSCs for mitochondrial transfer in both systems. In addition, REC-mediated mitochondrial transfer significantly restored mitochondrial function, including mitochondrial membrane potential, ATP/ROS production, intracellular calcium storage, and oxygen consumption rate. Moreover, mitochondrial function was maintained for at least three weeks. Thus, REC-donated exogenous mitochondria might offer a potential therapeutic strategy for treating neurological dysfunction in MELAS.

Extracellular Vesicles and Cx43-Gap Junction Channels Are the Main Routes for Mitochondrial Transfer from Ultra-Purified Mesenchymal Stem Cells, RECs.

Mitochondria are essential organelles for maintaining intracellular homeostasis. Their dysfunction can directly or indirectly affect cell functioning and is linked to multiple diseases. Donation of exogenous mitochondria is potentially a viable therapeutic strategy. For this, selecting appropriate donors of exogenous mitochondria is critical. We previously demonstrated that ultra-purified bone marrow-derived mesenchymal stem cells (RECs) have better stem cell properties and homogeneity than conventionally cultured bone marrow-derived mesenchymal stem cells. Here, we explored the effect of contact and noncontact systems on three possible mitochondrial transfer mechanisms involving tunneling nanotubes, connexin 43 (Cx43)-mediated gap junction channels (GJCs), and extracellular vesicles (Evs). We show that Evs and Cx43-GJCs provide the main mechanism for mitochondrial transfer from RECs. Through these two critical mitochondrial transfer pathways, RECs could transfer a greater number of mitochondria into mitochondria-deficient (ρ0) cells and could significantly restore mitochondrial functional parameters. Furthermore, we analyzed the effect of exosomes (EXO) on the rate of mitochondrial transfer from RECs and recovery of mitochondrial function. REC-derived EXO appeared to promote mitochondrial transfer and slightly improve the recovery of mtDNA content and oxidative phosphorylation in ρ0 cells. Thus, ultrapure, homogenous, and safe stem cell RECs could provide a potential therapeutic tool for diseases associated with mitochondrial dysfunction.

Highly-purified rapidly expanding clones, RECs, are superior for functional-mitochondrial transfer.

BACKGROUND: Mitochondrial dysfunction caused by mutations in mitochondrial DNA (mtDNA) or nuclear DNA, which codes for mitochondrial components, are known to be associated with various genetic and congenital disorders. These mitochondrial disorders not only impair energy production but also affect mitochondrial functions and have no effective treatment. Mesenchymal stem cells (MSCs) are known to migrate to damaged sites and carry out mitochondrial transfer. MSCs grown using conventional culture methods exhibit heterogeneous cellular characteristics. In contrast, highly purified MSCs, namely the rapidly expanding clones (RECs) isolated by single-cell sorting, display uniform MSCs functionality. Therefore, we examined the differences between RECs and MSCs to assess the efficacy of mitochondrial transfer. METHODS: We established mitochondria-deficient cell lines (ρ0 A549 and ρ0 HeLa cell lines) using ethidium bromide. Mitochondrial transfer from RECs/MSCs to ρ0 cells was confirmed by PCR and flow cytometry analysis. We examined several mitochondrial functions including ATP, reactive oxygen species, mitochondrial membrane potential, and oxygen consumption rate (OCR). The route of mitochondrial transfer was identified using inhibition assays for microtubules/tunneling nanotubes, gap junctions, or microvesicles using transwell assay and molecular inhibitors. RESULTS: Co-culture of ρ0 cells with MSCs or RECs led to restoration of the mtDNA content. RECs transferred more mitochondria to ρ0 cells compared to that by MSCs. The recovery of mitochondrial function, including ATP, OCR, mitochondrial membrane potential, and mitochondrial swelling in ρ0 cells co-cultured with RECs was superior than that in cells co-cultured with MSCs. Inhibition assays for each pathway revealed that RECs were sensitive to endocytosis inhibitor, dynasore. CONCLUSIONS: RECs might serve as a potential therapeutic strategy for diseases linked to mitochondrial dysfunction by donating healthy mitochondria.

Autopsy-confirmed hippocampal-sparing Alzheimer's disease with delusional jealousy as initial manifestation.

Alzheimer's disease (AD) is clinically characterized by gradual onset over years with worsening of cognition. The initial and most prominent cognitive deficit is commonly memory dysfunction. However, a subset of AD cases has less hippocampal atrophy than would be expected relative to the predominance of cortical atrophy. These hippocampal-sparing cases have distinctive clinical features, including the presence of focal cortical clinical syndromes. Given that previous studies have indicated that severe hippocampal atrophy corresponds to prominent loss of episodic memory, it is likely that memory impairment is initially absent in hippocampal-sparing AD cases. Here, we report on a patient with an 8-year history of delusional jealousy with insidious onset who was clinically diagnosed as possible AD and pathologically confirmed to have AD with relatively preserved neurons in the hippocampus. This patient had delusional jealousy with a long pre-dementia stage, which initially was characterized by lack of memory impairment. Head magnetic resonance imaging findings showed preserved hippocampal volume with bilateral enlarged ventricles and mild-to-moderate cortical atrophy. Head single-photon emission computed tomography revealed severely decreased regional cerebral blood flow in the right temporal lobe. The resolution of the delusion was attributed to pharmacotherapy by an acetylcholinesterase inhibitor, suggesting that the occurrence of delusional jealousy was due to the disease process of AD. Although the neural basis of delusional jealousy remains unclear, this hippocampal-sparing AD case may be classified as an atypical presentation of AD.

Ex Vivo Expanded Allogeneic Mesenchymal Stem Cells With Bone Marrow Transplantation Improved Osteogenesis in Infants With Severe Hypophosphatasia.

Patients with severe hypophosphatasia (HPP) develop osteogenic impairment with extremely low alkaline phosphatase (ALP) activity, resulting in a fatal course during infancy. Mesenchymal stem cells (MSCs) differentiate into various mesenchymal lineages, including bone and cartilage. The efficacy of allogeneic hematopoietic stem cell transplantation for congenital skeletal and storage disorders is limited, and therefore we focused on MSCs for the treatment of HPP. To determine the effect of MSCs on osteogenesis, we performed multiple infusions of ex vivo expanded allogeneic MSCs for two patients with severe HPP who had undergone bone marrow transplantation (BMT) from asymptomatic relatives harboring the heterozygous mutation. There were improvements in not only bone mineralization but also muscle mass, respiratory function, and mental development, resulting in the patients being alive at the age of 3. After the infusion of MSCs, chimerism analysis of the mesenchymal cell fraction isolated from bone marrow in the patients demonstrated that donor-derived DNA sequences existed. Adverse events of BMT were tolerated, whereas those of MSC infusion did not occur. However, restoration of ALP activity was limited, and normal bony architecture could not be achieved. Our data suggest that multiple MSC infusions, following BMT, were effective and brought about clinical benefits for patients with lethal HPP. Allogeneic MSC-based therapy would be useful for patients with other congenital bone diseases and tissue disorders if the curative strategy to restore clinically normal features, including bony architecture, can be established.

Antitumor effect of Japanese apricot extract (MK615) on human cancer cells in vitro and in vivo through a reactive oxygen species-dependent mechanism.

AIMS AND BACKGROUND: MK615 is produced from Japanese apricot and contains several cyclic triterpenes, such as oleanolic and ursolic acids. MK615 was shown to strongly suppress cutaneous in-transit metastasis in a patient with malignant melanoma. The present investigation was undertaken to clarify the antitumor effects of MK615 in vitro and in vivo. METHODS: Several human cancer cell lines were exposed to MK615 for 7 days to examine its antiproliferative effects. The effect of MK615 on in vivo growth of human pancreatic cancer MIAPaCa-2 cells was also examined. RESULTS: MK615 inhibited the growth of several human cancer cell lines in a concentration-dependent way. Pancreatic cancer MIAPaCa-2 cells were highly sensitive to the growth-inhibiting effects of MK615. Treatment with MK615 preferentially induced cell death in human cancer cells while sparing normal cells such as human umbilical vein endothelial cells (HUVEC) and mouse bone marrow cells. When MIAPaCa-2 cells were incubated with MK615 in the presence of antioxidant, growth-inhibition was significantly reduced, and MK615 induced the accumulation of reactive oxygen species in cancer cells but not in HUVEC. MK615, in both the presence and absence of gemcitabine, significantly inhibited the growth of human pancreatic cancer cells as xenografts without apparent adverse effects. CONCLUSIONS: MK615, a supplement produced from Japanese apricot, may have therapeutic value in treating human cancers through a reactive oxygen species-dependent mechanism.

Efficacy and tolerability of clozapine in Japanese patients with treatment-resistant schizophrenia: results from a 12-week, flexible dose study using raters masked to antipsychotic choice.

Japan approved clozapine for treatment-resistant schizophrenia in June 2009. The aim of this study was to evaluate clozapine's efficacy and tolerability in Japanese patients. A twelve-week, single-arm clinical trial of clozapine in treatment-resistant schizophrenia inpatients, was conducted under real-world conditions using raters masked for type of antipsychotic. Thirty-eight patients were recruited, with 33 (86.8%) completing the trial. At week 12, clozapine was associated with significant improvement in the Positive and Negative Syndrome Scale (PANSS) total (p < 0.0001), PANSS positive (p < 0.0001), negative (p = 0.0055) and general subscale scores (p < 0.0001). Significant improvements occurred in all PANSS scores by week 4, the first post-baseline psychopathology rating. Altogether, 50.0% of patients showed ≥20% reduction in PANSS total score, 20.6% had ≥30% reduction and 14.7% had >40% reduction. Eighteen patients (47.4%) were discharged before week 12. However, all patients experienced ≥1 adverse event. Two of 38 patients (5.2%) dropped out due to moderate leucopenia and one of them developed agranulocytosis after stopping clozapine. However, both patients recovered. Eight adverse events (hypersalivation, fatigue, sedation, constipation, insomnia, nausea/vomiting, chest pain and leucopenia) were observed in 34-79% of patients. These findings suggest that clozapine is beneficial in Japanese treatment-resistant schizophrenia patients. However, attention should be paid to patients' adverse events.

A novel fusicoccin derivative preferentially targets hypoxic tumor cells and inhibits tumor growth in xenografts.

Malignant cells in solid tumors survive under prolonged hypoxia and can be a source of resistance to current cancer therapies. Tumor hypoxia is also associated with a more malignant phenotype and poor survival in cancer patients. Recent progress in our understanding of the biology of tumor cells under hypoxia has led to increased attention on targeting hypoxia for cancer therapy. We report here that a novel fusicoccin derivative (ISIR-042), but not its parent or related compounds such as fusicoccin A and cotylenin A, is more cytotoxic to hypoxic cells than to normoxic cells. The hypoxia-induced accumulation of hypoxia-inducible factor (HIF)-1α and the phosphorylation of Akt were effectively inhibited by treatment with ISIR-042, suggesting that the preferential cytotoxicity toward hypoxic cells is associated with a reduction of HIF-1α and Akt activation. ISIR-042 inhibited the growth of human pancreatic cancer MIAPaCa-2 cells while sparing normal endothelial cells, and significantly inhibited the growth of MIAPaCa-2 cells as xenografts without apparent adverse effects. Pancreatic cancer cells expressing CD24 and CD44 exhibited characteristics of stem cells. Treatment with gemcitabine increased this stem cell-enriched population, and this effect was significantly inhibited by ISIR-042, suggesting that ISIR- 042 preferentially inhibits stem/progenitors in pancreatic cancer cell lines compared with chemotherapeutic agents. These results suggest that ISIR-042 may be a potential therapeutic agent for hypoxic tumors such as pancreatic cancer.

Risk factors for obstructive sleep apnea syndrome screening in mood disorder patients.

AIMS: Previous studies have reported that the incidence of obstructive sleep apnea syndrome (OSAS) in patients with depression is higher than in the general population. We examined the risk factors to predict OSAS in mood disorder patients with depressive symptoms. METHOD: We conducted polysomnography for patients who satisfied the following criteria: (i) diagnosis of major depressive disorder or bipolar disorder according to the Mini-International Neuropsychiatric Interview (MINI); (ii) a score of > or =10 on the Hamilton Rating Scale for Depression (HAM-D); (iii) fulfillment of either (a) or (b) below: (a) at least one of the following: severe snoring, witnessed apnea during sleep, excessive daytime sleepiness; (b) at least one of the following plus an oxygen desaturation index of 4% > or =5 times/h by pulse oximeter: mild snoring, sleep disturbance, headache, high blood pressure. The patients with apnea hypopnea index > or =5 were diagnosed with OSAS. RESULTS: Of the 32 mood disorder patients who met the subject conditions, 59.4% had OSAS. The diagnosis rate with our criteria was significantly higher than the previously reported incidence of OSAS in patients with depression. There was no significant difference among diagnosis rates as to individual risk factors or the number of risk factors. A multiple regression test showed no significant association between apnea-hypopnea index and other clinical factors including depression severity. CONCLUSION: The present results showed that OSAS can be detected at a remarkably higher rate by considering appropriate OSAS risk factors in mood disorder patients, and suggested that there is a high rate of undetected and therefore untreated OSAS among mood disorder patients.

Influence of negative cognition on the parental bonding instrument (PBI) in patients with major depression.

The aim of this study was to examine the effects of negative cognition on PBI score before and after treatment for depression. Forty major depressive disorder outpatients were assessed with the PBI scale and Structured Interview Guide for Hamilton Rating Scale for Depression (SIGH-D) at the time of the first medical examination (baseline) and 8 weeks later. The SIGH-D scores decreased by about 50% from baseline to 8 weeks, but there was no significant change in the PBI scores of the depressed outpatients from baseline to 8 weeks. Analysis of covariance with the SIGH-D scores as covariate was conducted for PBI scores between baseline and 8 weeks to remove effects of MDD. No significant differences were found on any of the PBI scales. Even though the therapeutic values on the SIGH-D of the depressed patients indicated that depressive symptoms were reduced by about 50%, depression level did not influence the PBI scores. This study provides evidence for the stability of parental representations throughout treatment, as measured by the PBI.