Plasticity of bone marrow-derived cell differentiation depending on microenvironments in the skin.

Bone marrow-derived cells (BMDCs) are heterogeneous populations in which not only pluripotent stem cells, namely, hematopoietic stem cells (HSCs), mesenchymal stem cells (MSC) but also endothelial progenitor cells (EPC) are involved. BMDCs contribute to the maintenance of homeostasis and recovery from disrupted homeostasis as the immune, endocrine, and nervous systems. The skin is the largest organ in which various tissues, such as the epidermis, dermis, skin appendages (i.e., hair follicles), fats, muscles, and vessels, are tightly and systematically packed. It functions as a physical barrier to block the invasion of harmful substances and pathogenic microorganisms and properly regulate water evaporation. The skin is exposed to injuries from external stimuli because it is the outermost layer and owing to its specificity. Recovery from physical injuries and DNA mutations occurs constantly in the skin, but medical treatments are required for impaired wound healing. Recently, conservative treatments utilizing scaffolds have attracted attention as alternatives to surgical therapy, which is highly invasive. Against this background, numerous scaffolds are available in a clinical setting, although they have not surpassed surgery because of their distinct disadvantages. Here, we discuss the plasticity of BMDCs in the skin to maintain homeostasis, in addition to their critical roles on recovery from disrupted homeostasis. We also share our perspective on how scaffolds can be developed to establish scaffolds beyond surgery to regenerate skin structure during wound healing by maximally utilizing the plasticity of BMDCs.

Aberrant bone marrow-derived microglia in the hypothalamus may dysregulate appetite in diabetes.

Bone marrow derived cells (BMDCs) migrate into the hypothalamus, where those cells give rise to microglia to regulate food intake. Given the fact that diabetes functionally impairs BMDCs, we hypothesized that diabetic microglia would fail to exhibit physiological function, accounting for hyperphagia in diabetes. To examine the role of BMDCs, total bone marrow cells from GFP transgenic mice were transplanted into wild type mice in which diabetes was induced by streptozotocin. We first confirmed that bone marrow transplantation could be utilized to examine BMDCs in the brain parenchyma as GFP positive cells could engraft the brain parenchyma and give rise to microglia even when the BBB was intact in the recipient mice. While diabetic mice manifested hyperphagia, BMDCs were in smaller number in the hypothalamus with less response to fasting in the brain parenchyma compared to nondiabetic mice. This finding was also confirmed by examining nondiabetic chimera mice in which BMDCs were diabetic. Those mice also exhibited less response of BMDCs in response to fasting. In conclusion, diabetic BMDCs had less response of microglia to fasting, perhaps accounting for diabetic hyperphagia.

Expression of proinflammatory cytokines and proinsulin by bone marrow-derived cells for fracture healing in long-term diabetic mice.

BACKGROUND: Diabetes mellitus (DM) causes bone dysfunction due to poor bone quality, leading to severe deterioration in patient of quality of life. The mechanisms of bone metabolism in DM remain unclear, although chemical and/or mechanical factors are known to disrupt the homeostasis of osteoblasts and osteoclasts. The purpose of this study was to identify the changes of osteoblasts and osteoclasts under long-term hyperglycaemic conditions, using a mouse fracture model of long-term hyperglycemia (LT-HG). METHODS: C57BL/6J mice and green fluorescent protein (GFP) -positive bone marrow transplanted C57BL/6J mice with LT-HG, maintained under a state of hyperglycaemia for 2 months, were used in this study. After the experimental fracture, we examined the immunohistochemical expression of proinsulin and tumor necrosis factor (TNF) -α at the fracture site. C57BL/6J fracture model mice without hyperglycaemia were used as controls. RESULTS: In the LT-HG mice, chondrocyte resorption was delayed, and osteoblasts showed an irregular arrangement at the callus site. The osteoclasts were scattered with a decrement in the number of nuclei. The expression of proinsulin was confirmed in bone marrow derived cells (BMDCs) with neovascularization 2 and 3 weeks after fracture. Immunopositivity for TNF-α was also confirmed in immature chondrocytes and BMDCs with neovascularization at 2 weeks, and the number of positive cells was not decreased at 3 weeks. Examination of GFP-grafted hyperglycaemic mice showed that the majority of cells at the fracture site were GFP-positive. Immunohistochemistry showed that the rate of double positives was 15% for GFP and proinsulin and 47% for GFP and TNF-α. CONCLUSION: LT-HG induces an increase in the number of proinsulin and TNF-α positive cells derived from BMDCs. We suggest that proinsulin and TNF-α positive cells are involved in both bone formation and bone resorption after fracture under hyperglycaemic conditions, resulting in the delay of bone healing.

Complete remission of diabetes with a transient HDAC inhibitor and insulin in streptozotocin mice.

Despite the growing epidemic worldwide, diabetes is an incurable disease. We have been focusing on why diabetes manifests refractoriness to any therapy. We recently found that abnormal bone marrow-derived cells (BMDCs), namely, Vcam-1+ST-HSCs, was a key mechanism for diabetic complications. We then hypothesize that those aberrant BMDCs sustainedly impair pancreatic ß cells. Here we show that eliminating abnormal BMDCs using bone marrow transplantation results in controlling serum glucose in diabetic mice, in which normoglycemia is sustained even after cessation of insulin therapy. Alternatively, abnormal BMDCs exhibiting epigenetic alterations are treated with an HDAC inhibitor, givinostat, in diabetic mice. As a result, those mice are normoglycemic along with restored insulin secretion even following the cessation of both insulin and givinostat. Diabetic cell fusion between abnormal BMDCs and resident cells is significantly blocked by the combination therapy in the pancreatic islets and thymus while surgical ablation of the thymus completely eliminates therapeutic protection in diabetic mice. In conclusion, diabetes is an epigenetic stem cell disorder with thymic disturbances. The combination may be applied to patients aiming at complete remission from diabetes in clinical medicine.

Fructose might be a clue to the origin of preeclampsia insights from nature and evolution.

Preeclampsia is a hypertensive disorder of pregnancy and is due to abnormal placentation. The pathogenesis remains unclear. Fructose is biologically distinct from glucose and has a critical role in fetal growth in early pregnancy. Many species, including humans, produce fructose in their placenta during the first trimester to assist fetal growth and survival during a time when hypoxia is significant. Fructose is preferred over glucose in hypoxic tissues, and in the developing fetus, fructose has a critical role in stimulating the production of nucleic acids, lipids and glycosaminoglycans. Fructose production normally decreases significantly following the establishment of maternal-fetal circulation following placentation. However, if there is impaired placentation, local hypoxia will continue to drive fructose production. Excessive fructose metabolism drives endothelial dysfunction, oxidative stress, elevated blood pressure, insulin resistance, fatty liver, and a rise in uric acid and vasopressin levels, all of which are features of the preeclamptic state. In addition to fructose production, dietary fructose, for example, from soft drinks, would be additive and has been reported to be a strong independent risk factor for preeclampsia. Uric acid-associated endothelial dysfunction disturbs the invasion of the spiral artery, leading to placental ischemia and further placental hypoxia. Here, we summarize the previous literature regarding the physiological and pathological roles of fructose in pregnancy and propose studies to further investigate the pathogenesis of preeclampsia. Fructose might be a Clue to the Origin of Preeclampsia Insights from Nature and Evolution Preeclampsia is a hypertensive disorder of pregnancy. The pathogenesis remains unclear. Fructose has a critical role in fetal growth in early pregnancy, and might be a key role to developing preeclampsia. Here, we summarize the previous literatures regarding the physiological andpathological roles of fructose in pregnancy to propose studies to further investigate the pathogenesis of preeclampsia.

Bone marrow-derived vasculogenesis leads to scarless regeneration in deep wounds with periosteal defects.

Deep skin wounds with periosteal defects, frequently caused by traffic accidents or radical dissection, are refractory. Transplant surgery is frequently performed, but patients are subjected to stress for long operation periods, the sacrifice of donor regions, or several complications, such as flap necrosis or intractable ulcers. Even if the defects are covered, a scar composed of fibrous tissue remains in the body, which can cause itching, dysesthesia, or repeated ulcers because of the lack of distribution of peripheral nerves or hair follicles. Thus, treatments with the aim of regenerating lost tissue for deep wounds with periosteal defects are needed. Here, we show that the use of gelatin sponges (GS), which have been used as haemostatic materials in clinical practice, allowed the regeneration of heterogeneous tissues, including periosteum, skin, and skin appendages, when used as scaffolds in deep wounds with periosteal defects in rats. Bone marrow transplantation in rats revealed the mechanism by which the microenvironment provided by GS enabled bone marrow-derived cells (BMDCs) to form a vascular niche, followed by regeneration of the periosteum, skin, or skin appendages such as hair follicles by local cells. Our findings demonstrated that vascular niche formation provided by BMDCs is crucial for heterogeneous tissue regeneration.

Ambient Temperature Is Correlated With the Severity of Neonatal Hypoxic-Ischemic Brain Injury via Microglial Accumulation in Mice.

Background: The pathophysiology of neonatal hypoxic-ischemic encephalopathy (HIE) has been studied in several rodent models to develop novel treatments. Although it is well known that high ambient temperature results in severe HIE, the effect of subtle changes in ambient temperature during a hypoxic-ischemic (HI) insult has not been studied. Therefore, in order to clarify the difference of pathophysiological change among the HIE models due to the influence of small changes in chamber temperature, three-step gradual change of 0.5°C each were prepared in ambient temperature during hypoxic exposure. Methods: Blood flow in the left common carotid artery (CCA) of neonatal mice was interrupted using bipolar electronic forceps under general and local anesthesia. The mice were subsequently subjected to 10% hypoxic exposure for 50 min at 36.0, 36.5, or 37.0°C. A control group was also included in the study. The size of the striatum and hippocampus and the volume reduction rate of the hemisphere in the section containing them on the ischemic side were evaluated using microtubule associated protein 2 (MAP2) immunostaining. The accumulation of Iba1-positive cells was investigated to assess inflammation. Additionally, rotarod and open-field tests were performed 2 weeks after HI insult to assess its effect on physiological conditions. Results: MAP2 staining revealed that the higher the temperature during hypoxia, the more severe the volume reduction rate in the hemisphere, striatum, and hippocampus. The number of Iba1-positive cells in the ipsilateral lesion gradually increased with increasing temperature, and there was a significant difference in motor function in the 36.5 and 37.0°C groups compared with the sham group. In the open-field tests, there was a significant decrease in performance in the 37.0°C groups compared with the 36.0°C and sham groups. Conclusions: Even a small gradual change of 0.5°C produced a significant difference in pathological and behavioral changes and contributed to the accumulation of Iba1-positive cells. The arrangement of ambient temperature is useful for creating a rodent model with the appropriate severity of the targeted neuropsychological symptoms to establish a novel therapy for HIE.

Excessive folic acid intake combined with undernutrition during gestation alters offspring behavior and brain monoamine profiles.

Dietary folic acid augmentation during gestation reduces neurodevelopmental disorder risk in offspring; however, it is still unclear if excessive maternal folic acid intake can impair brain function in offspring. We examined if excessive folic acid intake throughout gestation altered the behavior of male offspring under poor nutrition during early gestation (E5.5-E11.5). Dams were divided into four groups: control (CON, 2 mg folic acid/kg of food), excessive folic acid fortification (FF, 10 mg folic acid/kg of food), undernutrition (UN, 40% food reduction from E5.5-E11.5), and excessive folic acid fortification plus undernutrition (UN-FF). Excess maternal folic acid fortification induced hyperactivity in the open-field and lower anxiety-like behavior in the elevated plus maze at 9 weeks of age. These behavioral changes were accompanied by reduced dopamine in the prefrontal cortex (PFC), norepinephrine in the amygdala, and 5-hydroxytryptamine (5-HT) in the dorsal midbrain (DM), PFC, and amygdala where 5-HT neurons project from the DM. Furthermore, canonical discriminant analysis, including dopamine and DOPAC concentrations in the PFC, norepinephrine concentrations in the PFC, amygdala, and pons, and 5-HT and 5-HIAA concentrations in the amygdala and DM, correctly classified 73.5% of the offspring in CON, FF, UN, and UN-FF groups. The first discriminant function mainly classified groups based on nutritional status, whereas the second function mainly classified groups based on folic acid intake. Our study suggests that combined transformations of brain monoamine profiles by maternal undernutrition and excess folic acid intake is involved in the behavioral alteration of offsprings.

Bone marrow-derived inducible microglia-like cells ameliorate motor function and survival in a mouse model of amyotrophic lateral sclerosis.

BACKGROUND AIMS: Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease. Neuroinflammation in the spinal cord plays a pivotal role in the pathogenesis of ALS, and microglia are involved in neuroinflammation. Microglia mainly have two opposite phenotypes involving cytotoxic and neuroprotective properties, and neuroprotective microglia are expected to be a novel application for the treatment of ALS. Therefore, to establish a clinically applicable therapeutic method using neuroprotective microglia, the authors investigated the effect of inducing neuroprotective microglia-like cells from bone marrow for transplantation into ALS model mice. METHODS: Bone marrow-derived mononuclear cells were isolated from green fluorescent protein mice and cultured using different protocols of cytokine treatment with granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4. Cells with a high potency of proliferation and differentiation into microglia were evaluated by gene analysis, flow cytometry and direct neuroprotective effects in vitro. These cells were named bone marrow-derived inducible microglia-like (BM-iMG) cells and transplanted into the spinal cords of ALS model mice, and behavioral tests, immunohistochemistry and gene expression profiling were performed. RESULTS: Three-day GM-CSF and 4-day GM-CSF + IL-4 stimulations were most effective in inducing BM-iMG cells from the bone marrow. Transplantation of BM-iMG cells improved motor function, prolonged survival and suppressed neuronal cell death, astrogliosis and microgliosis in the spinal cords of ALS mice. Moreover, neuroprotective genes such as Arg1 and Mrc1 were upregulated, whereas pro-inflammatory genes such as Nos2 and Il6 were downregulated. CONCLUSIONS: Intraspinal transplantation of BM-iMG cells demonstrated therapeutic effects in a mouse model of ALS. Further studies and clinical applications in patients with ALS are expected in the future.

Endogenous Fructose Metabolism Could Explain the Warburg Effect and the Protection of SGLT2 Inhibitors in Chronic Kidney Disease.

Chronic low-grade inflammation underlies the pathogenesis of non-communicable diseases, including chronic kidney diseases (CKD). Inflammation is a biologically active process accompanied with biochemical changes involving energy, amino acid, lipid and nucleotides. Recently, glycolysis has been observed to be increased in several inflammatory disorders, including several types of kidney disease. However, the factors initiating glycolysis remains unclear. Added sugars containing fructose are present in nearly 70 percent of processed foods and have been implicated in the etiology of many non-communicable diseases. In the kidney, fructose is transported into the proximal tubules via several transporters to mediate pathophysiological processes. Fructose can be generated in the kidney during glucose reabsorption (such as in diabetes) as well as from intra-renal hypoxia that occurs in CKD. Fructose metabolism also provides biosynthetic precursors for inflammation by switching the intracellular metabolic profile from mitochondrial oxidative phosphorylation to glycolysis despite the availability of oxygen, which is similar to the Warburg effect in cancer. Importantly, uric acid, a byproduct of fructose metabolism, likely plays a key role in favoring glycolysis by stimulating inflammation and suppressing aconitase in the tricarboxylic acid cycle. A consequent accumulation of glycolytic intermediates connects to the production of biosynthetic precursors, proteins, lipids, and nucleic acids, to meet the increased energy demand for the local inflammation. Here, we discuss the possibility of fructose and uric acid may mediate a metabolic switch toward glycolysis in CKD. We also suggest that sodium-glucose cotransporter 2 (SGLT2) inhibitors may slow the progression of CKD by reducing intrarenal glucose, and subsequently fructose levels.

GLT1 gene delivery based on bone marrow-derived cells ameliorates motor function and survival in a mouse model of ALS.

Amyotrophic lateral sclerosis (ALS) is an intractable neurodegenerative disease. CD68-positive bone marrow (BM)-derived cells (BMDCs) accumulate in the pathological lesion in the SOD1(G93A) ALS mouse model after BM transplantation (BMT). Therefore, we investigated whether BMDCs can be applied as gene carriers for cell-based gene therapy by employing the accumulation of BMDCs. In ALS mice, YFP reporter signals were observed in 12-14% of white blood cells (WBCs) and in the spinal cord via transplantation of BM after lentiviral vector (LV) infection. After confirmation of gene transduction by LV with the CD68 promoter in 4-7% of WBCs and in the spinal cord of ALS mice, BM cells were infected with LVs expressing glutamate transporter (GLT) 1 that protects neurons from glutamate toxicity, driven by the CD68 promoter, which were transplanted into ALS mice. The treated mice showed improvement of motor behaviors and prolonged survival. Additionally, interleukin (IL)-1ß was significantly suppressed, and IL-4, arginase 1, and FIZZ were significantly increased in the mice. These results suggested that GLT1 expression by BMDCs improved the spinal cord environment. Therefore, our gene therapy strategy may be applied to treat neurodegenerative diseases such as ALS in which BMDCs accumulate in the pathological lesion by BMT.

Malfunctioning CD106-positive, short-term hematopoietic stem cells trigger diabetic neuropathy in mice by cell fusion.

Diabetic neuropathy is an incurable disease. We previously identified a mechanism by which aberrant bone marrow-derived cells (BMDCs) pathologically expressing proinsulin/TNF-α fuse with residential neurons to impair neuronal function. Here, we show that CD106-positive cells represent a significant fraction of short-term hematopoietic stem cells (ST-HSCs) that contribute to the development of diabetic neuropathy in mice. The important role for these cells is supported by the fact that transplantation of either whole HSCs or CD106-positive ST-HSCs from diabetic mice to non-diabetic mice produces diabetic neuronal dysfunction in the recipient mice via cell fusion. Furthermore, we show that transient episodic hyperglycemia produced by glucose injections leads to abnormal fusion of pathological ST-HSCs with residential neurons, reproducing neuropathy in nondiabetic mice. In conclusion, we have identified hyperglycemia-induced aberrant CD106-positive ST-HSCs underlie the development of diabetic neuropathy. Aberrant CD106-positive ST-HSCs constitute a novel therapeutic target for the treatment of diabetic neuropathy.

A novel role for bone marrow-derived cells to recover damaged keratinocytes from radiation-induced injury.

Exposure to moderate doses of ionizing radiation (IR), which is sufficient for causing skin injury, can occur during radiation therapy as well as in radiation accidents. Radiation-induced skin injury occasionally recovers, although its underlying mechanism remains unclear. Moderate-dose IR is frequently utilized for bone marrow transplantation in mice; therefore, this mouse model can help understand the mechanism. We had previously reported that bone marrow-derived cells (BMDCs) migrate to the epidermis-dermis junction in response to IR, although their role remains unknown. Here, we investigated the role of BMDCs in radiation-induced skin injury in BMT mice and observed that BMDCs contributed to skin recovery after IR-induced barrier dysfunction. One of the important mechanisms involved the action of CCL17 secreted by BMDCs on irradiated basal cells, leading to accelerated proliferation and recovery of apoptosis caused by IR. Our findings suggest that BMDCs are key players in IR-induced skin injury recovery.

Enhancing the Therapeutic Efficacy of Bone Marrow-Derived Mononuclear Cells with Growth Factor-Expressing Mesenchymal Stem Cells for ALS in Mice.

Several treatments have been attempted in amyotrophic lateral sclerosis (ALS) animal models and patients. Recently, transplantation of bone marrow-derived mononuclear cells (MNCs) was investigated as a regenerative therapy for ALS, but satisfactory treatments remain to be established. To develop an effective treatment, we focused on mesenchymal stem cells (MSCs) expressing hepatocyte growth factor, glial cell line-derived neurotrophic factor, and insulin-like growth factor using human artificial chromosome vector (HAC-MSCs). Here, we demonstrated the transplantation of MNCs with HAC-MSCs in ALS mice. As per our results, the progression of motor dysfunction was significantly delayed, and their survival was prolonged dramatically. Additional analysis revealed preservation of motor neurons, suppression of gliosis, engraftment of numerous MNCs, and elevated chemotaxis-related cytokines in the spinal cord of treated mice. Therefore, growth factor-expressing MSCs enhance the therapeutic effects of bone marrow-derived MNCs for ALS and have a high potential as a novel cell therapy for patients with ALS.

Bone-Marrow-Derived Mononuclear Cells Relieve Neuropathic Pain after Spinal Nerve Injury in Mice.

Treating neuropathic pain is a critical clinical issue. Although numerous therapies have been proposed, effective treatments have not been established. Therefore, safe and feasible treatment methods are urgently needed. In this study, we investigated the therapeutic effects of autologous intrathecal administration of bone-marrow-derived mononuclear cells (MNCs) on neuropathic pain. We generated a mouse model of neuropathic pain by transecting the spinal nerve and evaluated neuropathic pain by measuring the mechanical threshold in the following 14 days. Mice in the MNC injection group had a higher mechanical threshold than those in the buffer group. We assessed the effect of MNC treatment on the dorsal root ganglia and spinal cord by immunohistochemistry, mRNA expression, and cytokine assay. The migration and accumulation of microglia were significantly suppressed in the MNC group, and the mRNA expression of inflammatory cytokines such as interleukin (IL)-6, IL-1ß, and tumor necrosis factor alpha (TNF-α) was markedly downregulated. Furthermore, MNC administration tended to suppress various cytokines in the cerebrospinal fluid of the model mice. In conclusion, our results suggest that intrathecal injection of MNCs relieves neuropathic pain and might be a promising cell therapy for the treatment of this condition.

A 3D Printed Self-Sustainable Cell-Encapsulation Drug Delivery Device for Periocular Transplant-Based Treatment of Retinal Degenerative Diseases.

Self-sustainable release of brain-derived neurotrophic factor (BDNF) to the retina using minimally invasive cell-encapsulation devices is a promising approach to treat retinal degenerative diseases (RDD). Herein, we describe such a self-sustainable drug delivery device with human retinal pigment epithelial (ARPE-19) cells (cultured on collagen coated polystyrene (PS) sheets) enclosed inside a 3D printed semi-porous capsule. The capsule was 3D printed with two photo curable polymers: triethylene glycol dimethacrylate (TEGDM) and polyethylene glycol dimethylacrylate (PEGDM). The capsule's semi-porous membrane (PEGDM) could serve three functions: protecting the cells from body's immune system by limiting diffusion (5.97 ± 0.11%) of large molecules like immunoglobin G (IgG)(150 kDa); helping the cells to survive inside the capsule by allowing diffusion (43.20 ± 2.16%) of small molecules (40 kDa) like oxygen and necessary nutrients; and helping in the treatment of RDD by allowing diffusion of cell-secreted BDNF to the outside environment. In vitro results showed a continuous BDNF secretion from the device for at least 16 days, demonstrating future potential of the cell-encapsulation device for the treatment of RDD in a minimally invasive and self-sustainable way through a periocular transplant.

Transplantation of M2-Deviated Microglia Promotes Recovery of Motor Function after Spinal Cord Injury in Mice.

Despite the poor prognosis of spinal cord injury (SCI), effective treatments are lacking. Diverse factors regulate SCI prognosis. In this regard, microglia play crucial roles depending on their phenotype. The M1 phenotype exacerbates neuroinflammation, whereas the M2 phenotype promotes tissue repair and provides anti-inflammatory effects. Therefore, we compared the effects of M2 and M1 microglia transplantation on SCI. First, we established a method for effective induction of M1 or M2 microglia by exposure to granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin (IL)-4, respectively, to be used for transplantation in a SCI mouse model. In the M2 microglia transplantation group, significant recovery of motor function was observed compared with the control and M1 groups. Elevated transcription of several neuroprotective molecules including mannose receptor C type 1 (Mrc1), arginase 1 (Arg1), and insulin-like growth factor 1 (Igf1) was observed. Moreover, intramuscular injection of FluoroRuby dye revealed recovery of retrograde axonal transport from the neuromuscular junction to upstream of the injured spinal cord only in the M2-transplanted group, although the number of migrated microglia were comparable in both M1 and M2 groups. In conclusion, our results indicated that M2 microglia obtained by IL-4 stimulation may be a promising candidate for cell transplantation therapy for SCI.

Change in Brain Plasmalogen Composition by Exposure to Prenatal Undernutrition Leads to Behavioral Impairment of Rats.

Epidemiological studies suggest that poor nutrition during pregnancy influences offspring predisposition to experience developmental and psychiatric disorders. Animal studies have shown that maternal undernutrition leads to behavioral impairment, which is linked to alterations in monoaminergic systems and inflammation in the brain. In this study, we focused on the ethanolamine plasmalogen of the brain as a possible contributor to behavioral disturbances observed in offspring exposed to maternal undernutrition. Maternal food or protein restriction between gestational day (GD) 5.5 and GD 10.5 resulted in hyperactivity of rat male adult offspring. Genes related to the phospholipid biosynthesis were found to be activated in the PFC, but not in the NAcc or striatum, in the offspring exposed to prenatal undernutrition. Corresponding to these gene activations, increased ethanolamine plasmalogen (18:0p-22:6) was observed in the PFC using mass spectrometry imaging. A high number of crossings and the long time spent in the center area were observed in the offspring exposed to prenatal undernutrition and were mimicked in adult rats via the intravenous injection of ethanolamine plasmalogen (18:0p-22:6) incorporated into the liposome. Additionally, plasmalogen (18:0p-22:6) increased only in the PFC, and not in the NAcc or striatum. These results suggest that brain plasmalogen is one of the key molecules to control behavior, and its injection using liposome is a potential therapeutic approach for cognitive impairment.SIGNIFICANCE STATEMENT Maternal undernutrition correlates to developmental and psychiatric disorders. Here, we found that maternal undernutrition in early pregnancy led to hyperactivity in rat male offspring and induced gene activation of phospholipid-synthesizing enzyme and elevation of ethanolamine plasmalogen (18:0p-22:6) level in the PFC. Intravenous injection of ethanolamine plasmalogen (18:0p-22:6) incorporated into the liposome maintained crossing activity and the activity was circumscribed to the center area for a long time period, as in prenatally undernourished offspring with aberrant behavior. Furthermore, the amount of ethanolamine plasmalogen (18:0p-22:6) increased in the PFC of the rat after injection. Our result suggests that brain plasmalogen is one of the key molecules to control behavior and that its injection using liposome is a potential therapeutic approach for cognitive impairment.

Advanced Technology for Gene Delivery with Homing Peptides to Spinal Cord through Systemic Circulation in Mice.

Homing peptides to the spinal cord were identified and isolated using phage display technology. In vivo biopanning was performed by intravenous systemic injection of a phage library to screen specific peptides targeting the spinal cord of mice. Analyses of the sequences of targeted phages yielded two candidate peptides targeting the spinal cord: SP1 (C-LHQSPHI-C) and SP2 (C-PTNNPRS-C). These peptides were synthesized and intravenously injected into mice to evaluate their tissue specificity and potential as gene delivery carriers. The complexes between SP1 or SP2 peptides and the plasmid vector expressing the reporter gene could induce gene transduction in the spinal cord through systemic injection without gene expression in the brain, liver, and kidney. In addition, intravenous injection of the complex between SP1 and the vectors induced interleukin-4 expression in the spinal cord, resulting in effective suppression of lipopolysaccharide-induced hyperalgesia. Therefore, intravenously administered spinal cord homing peptides complexed with a plasmid vector provided tissue-specific treatment featuring gene delivery to the CNS through systemic circulation. This novel method of gene delivery is feasible and has great potential for clinical application.