Transplantation of hESCs-Derived Neural Progenitor Cells Alleviates Secondary Damage of Thalamus After Focal Cerebral Infarction in Rats.

Human embryonic stem cells-derived neural progenitor cells (hESCs-NPCs) transplantation holds great potential to treat stroke. We previously reported that delayed secondary degeneration occurs in the ventroposterior nucleus (VPN) of ipsilateral thalamus after distal branch of middle cerebral artery occlusion (dMCAO) in adult male Sprague-Dawley (SD) rats. In this study, we investigate whether hESCs-NPCs would benefit the neural recovery of the secondary damage in the VPN after focal cerebral infarction. Permanent dMCAO was performed with electrocoagulation. Rats were randomized into Sham, dMCAO groups with or without hESCs-NPCs treatment. HESCs-NPCs were engrafted into the peri-infarct regions of rats at 48 h after dMCAO. The transplanted hESCs-NPCs survive and partially differentiate into mature neurons after dMCAO. Notably, hESCs-NPCs transplantation attenuated secondary damage of ipsilateral VPN and improved neurological functions of rats after dMCAO. Moreover, hESCs-NPCs transplantation significantly enhanced the expression of BDNF and TrkB and their interaction in ipsilateral VPN after dMCAO, which was reversed by the knockdown of TrkB. Transplantated hESCs-NPCs reconstituted thalamocortical connection and promoted the formation of synapses in ipsilateral VPN post-dMCAO. These results suggest that hESCs-NPCs transplantation attenuates secondary damage of ipsilateral thalamus after cortical infarction, possibly through activating BDNF/TrkB pathway, enhancing thalamocortical projection, and promoting synaptic formation. It provides a promising therapeutic strategy for secondary degeneration in the ipsilateral thalamus post-dMCAO.

Inhibition of Hypothalamic FTO Activates STAT3 Signal through ERK1/2 Associated with Reductions in Food Intake and Body Weight.

INTRODUCTION: Fat mass and obesity-associated (FTO) gene is strongly associated with obesity which brings a major health threat. Altered expression of its encoded protein FTO in the hypothalamus has been identified to contribute to central control of appetite and body weight. However, its molecular mechanisms remain elusive. METHODS: Mouse hypothalamic POMC cell line N43/5 was treated with FTO inhibitor rhein, FTO shRNA, or extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor U0126 to inhibit FTO or ERK1/2. Rhein and U0126 were injected into lateral ventricle of the mice by intracerebroventricular cannulation. Western blotting and immunofluorescent assays were performed to monitor protein level. RESULTS: This study identified that inhibition of FTO in N43/5 cells led to phosphorylation of signal transducer and activator of transcription 3 (STAT3) at S727 site and induced p-STAT3-S727 nuclear translocation. We further showed that FTO inhibition promoted phosphorylation of ERK1/2; specific inhibition of ERK1/2 signaling by U0126 could abolish the effect of FTO inhibition on STAT3-S727 phosphorylation and nuclear translocation. Furthermore, we found that inhibition of hypothalamic FTO promoted STAT3-S727 phosphorylation in the hypothalamic arcuate nucleus, and the mice showed reductions in food intake and body weight. In addition, inhibition of hypothalamic ERK1/2 could abolish the effects of FTO inhibition on STAT3-S727 phosphorylation, reductions of food intake and body weight. CONCLUSION: Our in vitro and in vivo data suggest that the inhibition of hypothalamic FTO could activate STAT3 through ERK1/2, which is potentially associated with reductions in food intake and body weight.

FMRP-absence-induced up-regulation of hypothalamic MAP1B expression decreases AgRP level linking with reduces in food intake and body weight.

Fragile X mental retardation protein (FMRP), strongly associated with fragile X syndrome, plays important roles by regulating gene expression via interacting with other RNA binding proteins in the brain. However, the role of FMRP in hypothalamus, a central part responsible for metabolic control, is poorly known. Our study shows that FMRP is primarily located in the hypothalamic arcuate nucleus (ARC). Using proteomic analysis, we identified 56 up-regulated and 22 down-regulated proteins in the hypothalamus of Map1b KO mice, with microtubule-associated protein 1 B (MAP1B) being the most outstanding increased protein (more than 10 folds). Immunofluorescent assays showed that MAP1B significantly increased in the Map1b-KO ARC, in which the number of agouti-related peptide (AgRP)-staining neurons significantly reduced, but not altered for pro-opiomelanocortin (POMC) neurons. We further showed an age-dependent reduces in food intake and body weight of the KO mice, along with the decreases of MAP1B and AgRP at the same time points. In hypothalamic GT1-7 cells, the AgRP expression decreased upon knockdown of FMRP or overexpression of MAP1B, and increased in response to overexpression of FMRP or knockdown of MAP1B. Co-knockdown or co-overexpression of FMRP and MAP1B led to a reverse expression of AgRP compared to overexpression of knockdown of FMRP alone, demonstrating that MAP1B is essential for the regulatory effect of FMRP on AgRP expression. Taken together, these data suggest that FMRP-deficiency-induced increase of hypothalamic MAP1B and decrease of AgRP might be associated with reduces in food intake and body weight.

Attenuation of secondary damage and Aß deposits in the ipsilateral thalamus of dMCAO rats through reduction of cathepsin B by bis(propyl)-cognitin, a multifunctional dimer.

Delayed secondary degeneration in the non-ischemic sites such as ipsilateral thalamus would occur after cortical infarction. Hence, alleviating secondary damage is considered to be a promising novel target for acute stroke therapy. In the current study, the neuroprotective effects of bis(propyl)-cognitin (B3C), a multifunctional dimer, against secondary damage in the VPN of ipsilateral thalamus were investigated in a distal middle cerebral artery occlusion (dMCAO) stroke model in adult rats. It was found that B3C (0.5 and 1 mg/kg, ip) effectively improved neurological function of rats at day 7 and day 14 after dMCAO. Additionally, the treatment with B3C alleviated neuronal loss and gliosis in ipsilateral VPN after dMCAO, as evidenced by the higher immunoreactivity of neuron-specific nuclear-binding protein (NeuN) as well as lower immunostaining intensity of glial fibrillary acidic protein (GFAP) and cluster of differentiation 68 (CD68). Most encouragingly, immunohistochemistry and western blotting further revealed that B3C treatment greatly reduced Aß deposits and cathepsin B expression in the VPN of ipsilateral thalamus at day 7 and day 14 after dMCAO. In parallel, we demonstrated herein that the neuroprotective effects of B3C in dMCAO model were similar to L-3-trans-(Propyl-carbamoyloxirane-2-carbonyl)- L-isoleucyl-l-proline methyl ester (CA-074Me), a specific inhibitor of cathepsin B, suggesting that B3C attenuated secondary damage and Aß deposits in the VPN of ipsilateral thalamus after dMCAO possibly through the reduction of cathepsin B. These findings taken together provide novel molecular sights into the potential application of B3C for the treatment of secondary degeneration after cortical infarction.

Different concentrations of docosahexanoic acid supplement during lactation result in different outcomes in preterm Sprague-Dawley rats.

PROPOSE: In this study, we evaluated the effects of different concentrations of docosahexanoic acid (DHA) supplement on preterm Sprague-Dawley rat pups, and in parallel, measured the phosphorylation activity of the mTOR pathway in the hippocampal CA1 area. METHODS: Preterm Sprague-Dawley rat pups were randomly assigned to experimental groups which included; a sufficient DHA group (100 mg/kg/day); an enriched DHA group (300 mg/kg/day); an excess DHA group (800 mg/kg/day); and a deficient DHA group (normal saline gavage 0.1 ml/10 g). Body weight (g) was measured at days 1/7/14/21/28/42, respectively. Spatial learning and memory were also tested using the Morris water maze at week 6 (day 42). Finally, activation of the mTOR signaling pathway in hippocampal CA1 area were evaluated by western blotting. RESULTS: Postnatal sufficient/enriched docosahexanoic acid supplement ameliorated body weight restriction, spatial learning and memory restriction, and decreased phosphorylation of AKT, mTOR, P70S6K1, and 4EBP1 in hippocampal CA1 area. Furthermore, excess docosahexanoic acid supplement impeded weight gain and spatial learning and memory, perturbed serum unsaturated fatty acid, and downregulated phosphorylation of AKT, mTOR, P70S6K1, and 4EBP1 in hippocampal CA1 area. CONCLUSION: Postnatal sufficient/enriched DHA supplement ameliorated growth and spatial learning and memory impairment and upregulated the mTOR pathway in preterm pups, although excessive DHA supplement did not have any beneficial effects.

Inhibition of Cathepsin B Alleviates Secondary Degeneration in Ipsilateral Thalamus After Focal Cerebral Infarction in Adult Rats.

Secondary degeneration in areas beyond ischemic foci can inhibit poststroke recovery. The cysteine protease Cathepsin B (CathB) regulates cell death and intracellular protein catabolism. To investigate the roles of CathB in the development of secondary degeneration in the ventroposterior nucleus (VPN) of the ipsilateral thalamus after focal cerebral infarction, infarct volumes, immunohistochemistry and immunofluorescence, and Western blotting analyses were conducted in a distal middle cerebral artery occlusion (dMCAO) stroke model in adult rats. We observed marked neuron loss and gliosis in the ipsilateral thalamus after dMCAO, and the expression of CathB and cleaved caspase-3 in the VPN was significantly upregulated; glial cells were the major source of CathB. Although it had no effect on infarct volume, delayed intracerebroventricular treatment with the membrane-permeable CathB inhibitor CA-074Me suppressed the expression of CathB and cleaved caspase-3 in ipsilateral VPN and accordingly alleviated the secondary degeneration. These data indicate that CathB mediates a novel mechanism of secondary degeneration in the VPN of the ipsilateral thalamus after focal cortical infarction and suggest that CathB might be a therapeutic target for the prevention of secondary degeneration in patients after stroke.

Protective effects of blocking renin-angiotensin system on the progression of renal injury in glomerulosclerosis.

To investigate the protective effects of blocking rennin-angiotensin system (RAS) on the progression of renal injury in glomerulosclerosis, a glomerulosclerosis model was made for SD rats by unilateral nephrectomy and being injected with Adriamycin into caudal vein. The rats with glomerulosclerosis were randomly divided as ten per group into those without further treatment (group D) and those treated with Benazepril (group DB), Losartan (group DL), or sham-operation (group C), respectively. After 6 weeks of administration of Benazepril or Losartan, the mRNA expressions of TGF-beta1, Col IV, Fn, ET-1 and iNOS in renal cortex were measured by RT-PCR. Besides, the expressions of TGF-beta1, ET-1 and iNOS at protein level were detected by Western blotting and the concentrations of Col IV and Fn were analyzed with immunohistochemistry respectively. Results showed that the rats in group D appeared as obvious proteinuria, hypoalbuminemia and hypercholesterolemia, which had a significant difference compared with group C (p < 0.05), and most of their mesangiums were detected with cellular proliferation and significant increasing for extracellular matrix. Renal cortex TGF-beta1, Col IV, Fn, ET-1 and iNOS in rats of group D were increased by 3.59, 2.57, 2.21, 2.58 and 3.28 times at mRNA level, and by 2.60, 1.40, 0.75, 1.83 and 2.15 times at protein level, respectively, compared with group C. When the animals were treated with Benazepril (group DB) or Losartan (group DL), however, the biochemical and pathological damages were significantly recovered, and protein expressions of TGF-beta1, Col IV, Fn, ET-1 and iNOS were also significantly diminished (p < 0.05). This study suggested that blocking RAS using Benazepril or Losartan can have protective effects on the renal injury in glomerulosclerosis by down-regulating the expressions of TGF-beta1, Col IV, Fn, ET-1 and iNOS.

Study of antiepileptic effect of extracts from Acorus tatarinowii Schott.

PURPOSE: To study the antiepileptic properties of extracts from rhizomes of Acorus tatarinowii Schott (ATS). METHODS: The decoction and volatile oil were extracted from rhizomes of ATS by traditional decocting and supercritical CO(2) fluid extraction (SFE-CO(2)) methods. Maximal electroshock (MES), pentylenetetrazol (PTZ) maximal seizure, and prolonged PTZ kindling models were used to test their anticonvulsive properties. The gamma-aminobutyric acid (GABA) immunohistochemical reaction (IR) was used to study GABAergic neuron changes in the PTZ kindling model and the effects of treatment. RESULTS: Both decoction (dose; 10-20 g/kg) and volatile oil (1.25 g/kg) of ATS decreased the convulsive rate significantly in the MES model. Decoction of ATS was shown to be effective in the PTZ model with both decreased convulsive and mortality rates. The volatile oil of ATS failed to prevent seizures in the dose range tested, although prolonged seizure latency and decreased mortality were found at a dose of 1.25 g/kg. In the PTZ kindling model, GABA-IR neurons decreased obviously compared with the normal group. In the groups treated with the decoction and volatile oil, the seizure intensity decreased significantly after treatment. Increased GABA-IR neurons also were found when compared with PTZ kindling controls. Morphologic observation also showed that GABA-IR neuron damage was less severe in the drug-treated groups. CONCLUSIONS: Both decoction and volatile oil extracted from the rhizome of Acorus tatarinowii Schott have anticonvulsive effects. The volatile oil is shown to be less effective for PTZ-induced convulsions. Both extracts can prevent convulsions as well as convulsion-related GABAergic neuron damage in the brain in the prolonged PTZ kindling model.