Lactate: a new target for brain disorders.

Lactate in the brain is produced endogenously and exogenously. The primary functional cells that produce lactate in the brain are astrocytes. Astrocytes release lactate to act on neurons, thereby affecting neuronal function, through a process known as the astrocyte-neuron shuttle. Lactate affects microglial function as well and inhibits microglia-mediated neuroinflammation. Lactate also provides energy, acts as a signaling molecule, and promotes neurogenesis. This article summarizes the role of lactate in cells, animals, and humans. Lactate is a protective molecule against stress in healthy organisms and in the early stages of brain disorders. Thus, lactate may be a potential therapeutic target for brain disorders. Further research on the role of lactate in microglia may have great prospects. This article provides a new perspective and research direction for the study of lacate in brain disorders.

The antidepressant effects of protein arginine methyltransferase 2 involve neuroinflammation.

Protein arginine methyltransferase (PRMT) 2 catalyzes the methylation of arginine residues in histones. Depression is associated with histone methylation; however, more comprehensive research is needed on how PRMT2 regulates depression. The present study aimed to investigate the effects and possible mechanism(s) of PRMT2 overexpression on depression-like behavior induced by chronic unpredictable mild stress (CUMS) in rats, and whether lentivirus-mediated PRMT2 overexpression in the hippocampus suppresses depression-like behavior. Furthermore, the PRMT2 inhibitor MS023 was administered to the animals to investigate whether the antidepressant effect of PRMT2 overexpression could be reversed. Behavioral experiments were performed to detect depression-like behavior in rats. Western blotting was used to determine protein expression levels of PRMT2, histone H3R8 asymmetric dimethylation (H3R8me2a), inducible nitric oxide synthase (iNOS), and arginase 1 (Arg1) in rat hippocampal tissues. Hippocampal microglia and PRMT2 were stained using immunofluorescence techniques. Enzyme-linked immunosorbent assay was used to determine the levels of various inflammatory factors in rat hippocampal tissue. Results of analysis revealed that PRMT2 overexpression in the hippocampus exerted an antidepressant effect. PRMT2 overexpression in the hippocampus reduced the proportion of activated microglia in the hippocampus, upregulated Arg1 and H3R8me2a expression, and downregulated iNOS expression. PRMT2 overexpression in the hippocampus inhibited the release of pro-inflammatory factors and promoted the release of anti-inflammatory factors. In summary, PRMT2 overexpression in the hippocampus promoted the conversion of microglia from the M1 to M2 type, resulting in an antidepressant effect. These results suggest that PRMT2 may be a potential therapeutic target to prevent and treat depression.

Zinc Homeostasis: An Emerging Therapeutic Target for Neuroinflammation Related Diseases.

Zinc is an indispensable trace element in the human body and plays an important role in regulating normal growth and development. Zinc homeostasis in the central nervous system is closely related to the development of neuroinflammation, and synaptic zinc homeostasis disorders affect zinc homeostasis in the brain. Under the condition of synaptic zinc homeostasis, proper zinc supplementation improves the body's immunity and inhibits neuroinflammation. Synaptic zinc homeostasis disorder in the brain promotes the occurrence and development of neuroinflammation. Cerebral ischemia and hypoxia cause a massive release of synaptic Zn2+ into the synaptic cleft, resulting in neurotoxicity and neuroinflammation. Synaptic zinc homeostasis disorder is a high-risk factor for neurodegenerative diseases. Maintaining cerebral zinc homeostasis suppresses the progression of neuroinflammation-mediated neurodegenerative diseases. This article reviews the relationship between brain zinc homeostasis and neuroinflammation and proposes that maintaining synaptic zinc homeostasis prevents neuroinflammation.

Relationship between protein arginine methyltransferase and cardiovascular disease (Review).

Protein arginine methyltransferases (PRMTs) are widely found in eukaryotes and regulate gene expression and post-translational modifications. PRMT1-PRMT6 have important roles in the pathology of cardiovascular diseases (CVDs), including atherosclerosis, heart failure and myocardial hypertrophy. Although these enzymes are also closely associated with various CVDs, the mechanisms of the involvement of PRMTs in the regulation of CVD have remained largely elusive. PRMTs methylate arginine residues and other factors. The present review describes the roles of PRMT1-PRMT6 in CVD. Furthermore, the biological characteristics of PRMTs and mechanisms by which PRMTs regulate cholesterol metabolism are being introduced. This review aims to provide inspiration for cardiovascular drug research and offer clues for research on the pathogenesis of CVD.

New Target for Prevention and Treatment of Neuroinflammation: Microglia Iron Accumulation and Ferroptosis.

Microglia play an important role in maintaining central nervous system homeostasis and are the major immune cells in the brain. In response to internal or external inflammatory stimuli, microglia are activated and release numerous inflammatory factors, thus leading to neuroinflammation. Inflammation and microglia iron accumulation promote each other and jointly promote the progression of neuroinflammation. Inhibiting microglia iron accumulation prevents neuroinflammation. Ferroptosis is an iron-dependent phospholipid peroxidation-driven type of cell death regulation. Cell iron accumulation causes the peroxidation of cell membrane phospholipids and damages the cell membrane. Ultimately, this process leads to cell ferroptosis. Iron accumulation or phospholipid peroxidation in microglia releases a large number of inflammatory factors. Thus, inhibiting microglia ferroptosis may be a new target for the prevention and treatment of neuroinflammation.

[Voluntary wheel running exercise regulates microglia polarization in hippocampus through STAT3 signal pathway to inhibit depression-like behavior induced by chronic stress in rats].

This paper was aimed to investigate the effect of voluntary wheel running exercise on depression-like behavior induced by chronic water immersion restraint stress (CWIRS) and the underlying mechanism. Sprague-Dawley (SD) rats received CWIRS to induce depression-like behavior and 4-week voluntary wheel running exercise. Meanwhile, the rats were treated with lipopolysaccharide (LPS) or STAT3 over-expression vector (pcDNA-STAT3) by intracerebroventricular injection. Behavioral tests were used to detect depression-like behavior. ELISA assay was used to detect levels of various inflammatory factors in the rat hippocampus. Western blot was used to detect protein expression levels of ionized calcium binding adaptor molecule 1 (Iba1), inducible nitric oxide synthase (iNOS), arginase 1 (Arg1), phosphorylated STAT3 (p-STAT3) and total STAT3 (t-STAT3). The results showed that, compared with stress group, stress + exercise group exhibited improved depression-like behavior, decreased interleukin-1ß (IL-1ß) and IL-6 levels, increased IL-4 and IL-10 levels, down-regulated Iba-1 and iNOS protein expression levels, up-regulated Arg1 protein expression level, and decreased p-STAT3/t-STAT3 ratio in hippocampal tissue. LPS reversed the improving effect of voluntary wheel running exercise on depression-like behavior in rats, and the over-expression of STAT3 reversed the promoting effects of voluntary wheel running on M2 polarization of microglial cells in rat hippocampus and depression-like behavior. These results suggest that voluntary wheel running ameliorates the depression-like behavior induced by CWIRS in rats, and the mechanism may be related to regulating hippocampal microglia polarization via STAT3 signaling pathway.

Research Progress on Mechanism of Neuroprotective Roles of Apelin-13 in Prevention and Treatment of Alzheimer's Disease.

Alzheimer's disease (AD) is the most common type of dementia. Currently, more than 50 million people live with dementia worldwide, and this number is expected to increase. Some of the typical pathological changes of AD include amyloid plaque, hyperphosphorylation of tau protein, secretion of inflammatory mediators, and neuronal apoptosis. Apelin is a neuroprotective peptide that is widely expressed in the body. Among members of apelin family, apelin-13 is the most abundant with a high neuroprotective function. Apelin-13/angiotensin domain type 1 receptor-associated proteins (APJ) system regulates several physiological and pathophysiological cell activities, such as apoptosis, autophagy, synaptic plasticity, and neuroinflammation. It has also been shown to prevent AD development. This article reviews the research progress on the relationship between apelin-13 and AD to provide new ideas for prevention and treatment of AD.

Advances in the role of autophagy in the development of retinoblastoma.

Autophagy is a feedback regulatory mechanism of cells to external stress, which helps cells to adapt to changes in physiological conditions and environmental stress. Autophagy possesses a variety of target genes that control a wide range of signaling pathways. Maintenance of an appropriate level of autophagy is essential for the growth, metastasis and characteristics of tumors. Retinoblastoma (RB) is the most common primary intraocular malignant tumor found in the eyes of children following exposure to extreme environmental factors, such as mitochondrial defects, oxidative stress and excessive autophagy; this leads to the development of DNA damage and progressive loss of the function of the eye, which results in the occurrence of RB. Recent studies have documented the involvement of autophagy in the transformation, occurrence and metastasis of RB. High or low levels of autophagy exert notably promotive or repressive effects on the development, invasion, drug resistance and survival of RB, respectively. The present review reports the research progress on the association between autophagy and RB.

PRMT2 inhibits the formation of foam cell induced by ox-LDL in RAW 264.7 macrophage involving ABCA1 mediated cholesterol efflux.

OBJECTIVES: Protein arginine methyltransferase 2 (PRMT2) is closely related to the occurrence and development of atherosclerosis. However, its underlying mechanisms remain to be elucidated. The purpose of this study is to observe the effect of overexpression of PRMT2 on the formation of foam cells and to explore its possible mechanism in RAW 264.7 macrophage. METHODS: Lentivirus vector of overexpression PRMT2 (LV-PRMT2) was constructed. LV-PRMT2 and lentivirus vector GV492 were transfected into RAW 264.7 macrophages, positive clone cells were screened by treatment with 4.0 µg/mL puromycin for 4 weeks. The macrophages were treated with ox-LDL (50 µg/mL) for 48 h to induce foaming. The lipid accumulation of macrophages was observed by oil red O staining. The levels of cellular total cholesterol (TC), free cholesterol (FC) and cholesteryl ester (CE) were measured by high performance liquid chromatography (HPLC) assays. The cholesterol efflux of macrophages was tested by the [3H] labeled cholesterol. The expressions of ATP binding cassette transporter A1 (ABCA1), ATP binding cassette transporter G1 (ABCG1), CD36 and scavenger receptor A1 (SR-A1) in macrophages were measured by Western Blot. RESULTS: The results showed that LV-PRMT2 and lentivirus vector has been successfully transfected into RAW 264.7 macrophage. Compared with the Vector group, the mRNA and protein expressions of PRMT2 were significantly up-regulated (P < 0.05). Compared with Control group, the expression of PRMT2 was significantly down-regulated in ox-LDL group (P < 0.05). A large number of red lipid droplets appeared in the cells in Vector group. Compared with Vector group, lipid droplets, the levels of TC, FC and CE and CE/TC, cholesterol efflux rate and expression of ABCA1 in RAW 264.7 macrophage was significantly decreased in LV-PRMT2 group (all P < 0.05). There was no significant difference about the expressions of ABCG1, CD36 and SR-A1 between LV-PRMT2 group and Vector group (all P > 0.05). CONCLUSIONS: Overexpression of PRMT2 inhibits the formation of foam cell induced by ox-LDL in RAW 264.7 macrophage, and the mechanism may be related to the increase of ABCA1 expression and ABCA1 mediated cholesterol efflux.

Microglia polarization of hippocampus is involved in the mechanism of Apelin-13 ameliorating chronic water immersion restraint stress-induced depression-like behavior in rats.

Chronic stress induces the activation of hippocampal microglia, which produces many inflammatory mediators and mediates the occurrence of depression. Two phenotypes of microglia polarization, the classical M1 and alternative M2, play important regulatory roles in neuroinflammation and are involved in the occurrence and development of depression. Apelin is derived from a precursor peptide consisting of 77 amino acids and is a natural ligand for the orphan G-protein-coupled receptor APJ. Apelin-13 is one of the subtypes of Apelin and has a wide range of biological effects. Studies have shown that Apelin-13 has an antidepressant effect, but its specific mechanism has not been elucidated. In this study, the purpose of this study is to explore the possible mechanism of Apelin-13 to improve depression-like behaviors induced by chronic stress in rats from the perspective of microglial polarization in vivo. Adult male Sprague Dawley (SD) rats received 28 days of chronic water immersion restraint stress (CWIRS). Apelin group was injected with Apelin-13 (2 µg/2 µL) through the intracerebroventricular for 7 days. The results showed that CWIRS can induce depression-like behaviors in rats. Compared with the CWIRS + saline group, the CWIRS + Apelin-13 group was significantly improved the depression-like behaviors in rats. Compared with the CWIRS + saline group, the CWIRS + Apelin-13 group was significantly down-regulated the protein expression of M1-type marker iNOS and the pro-inflammatory factors IL-1ß and IL-6 secret by microglia decreased. Compared with the CWIRS + saline group, the protein expression of M2-type marker Arg1 and anti-inflammatory factors IL-4 and IL-10 secreted by microglia was significantly increased in CWIRS + Apelin-13 group. Double-labelling immunofluorescence co-localization showed that, compared with the CWIRS + saline group, CWIRS + Apelin-13 group significantly inhibited the co-localization expression of Iba-1 and iNOS, and promoted the co-localization expression of Iba-1 and Arg1 in hippocampus microglia. Taken together, our study suggests that Apelin-13 improves depression-like behavior in rats induced by CWIRS and its mechanism may be related to the regulation of microglial polarization.

Apelin-13 regulates LPS-induced N9 microglia polarization involving STAT3 signaling pathway.

The process of neurodegenerative diseases has always been accompanied by neuroinflammatory response characterized by microglia activation. Two phenotypes of microglial polarization: the classically activated M1 type and the alternative activated M2 type, have been described. Although apelin-13 has been shown to have neuroprotective effects, its specific mechanism of anti-neuritis is still unclear. The aim of this study was to investigate whether apelin-13 can exert anti-neuroinflammatory effects by regulating the polarization of N9 microglia. MTT assay showed that 0.1 µM apelin-13 (24 h) and 2 µg/mL LPS (6 h) treatment had no significant effect on cell viability of N9 microglia. The combined treatment of Apelin-13 and LPS did not affect the viability of N9 microglia. N9 microglia were pretreated with 0.1 µM apelin-13 for 24 h, followed by incubation with LPS for 6 h. Morphological results indicated that apelin-13 (0.1 µM) inhibited LPS-induced N9 microglial activation as observed by smaller soma and slender process compared to LPS-treated group. Western blot confirmed that apelin-13 decreased the level of proinflammatory factor iNOS, IL-6 and up-regulated the level of anti-inflammatory factor arg-1 and IL-10 in N9 microglia. Flow cytometry revealed that apelin-13 inhibited the expression of M1 microglia activation marker CD86 and up-regulated the expression of M2 marker CD206. Furthermore, the data displayed that apelin-13 decreased the expression of p-STAT3 and the radio of p-STAT3/t-STAT3 in M1-type N9 microglia induced by LPS. In conclusion, our results indicated apelin-13 ameliorated neuroinflammation by shifting N9 microglial M1 polarization toward the M2 phenotype, the underlying mechanism of which may be related to STAT3 signals.

Inflammation and airway remodeling of the lung in guinea pigs with allergic rhinitis.

Allergic rhinitis (AR) and asthma belong to the category of type I allergic diseases, whose pathological features are airway remodeling of the lung and allergic inflammation. The aim of the present study was to evaluate inflammation and remodeling of lung tissue in a guinea pig model of AR in order to confirm consistent pathological changes of upper and lower airways in AR. Male guinea pigs were randomly divided into an experimental and a control group (n=10 in each). The AR model was established by sensitization through intraperitoneal injection of ovalbumin for three weeks and bilateral nasal local excitation for twelve weeks. All tissues of nasal mucosa and lung were subjected to hematoxylin and eosin as well as toluidine blue staining, and characteristics of remodeling of lung tissue, including thickness of bronchial wall, epithelial mucosa and smooth muscle were histologically determined. Collagen deposition in lung tissue was observed by Masson's trichrome stain. Severe paroxysmal nose scratching action, frequent sneezing, visible outflow of secretion from the anterior naris and frequent nose friction were observed in the AR model group within 30 min after local excitation. The total symptom scores were significantly increased in the AR model group compared with those in the control group. Obvious inflammatory cell infiltration was observed in the AR model group. Compared with those in the control group, the numbers of eosinophils and mast cells in nasal mucosa and lung tissue were significantly increased. Obvious airway remodeling of the lung was observed in the AR model group. Compared with those in the control group, bronchial wall thickness, epithelial layer thickness and smooth muscle thickness in the airways were significantly increased in the AR model group. Increased collagen deposition was found in the AR model group compared with that in the control group. The results of the present study revealed that inflammation and airway remodeling of lungs arose in guinea pigs with AR, suggesting that pathological changes of upper and lower airways are consistent in this AR model.

Apelin-13 Protects PC12 Cells from Corticosterone-Induced Apoptosis Through PI3K and ERKs Activation.

It is widely accepted that environmental stress is a risk factor for mental disorders. Glucocorticoid hormones play a vital role in the regulation of physiological response to stress. High concentrations of corticosterone can induce cellular damage in PC12 cells, which possess typical neuronal features. Apelin and its receptor APJ are widely distributed in the central nervous system including limbic structures involved in stress responses. Previous studies have suggested that apelin has a neuroprotective function. However, the effect of apelin on corticosterone-induced neuronal damage remains to be elucidated. In the present study, we explored the potential protective activity of apelin-13 in PC12 cells treated with corticosterone and its underling mechanisms. The viability of the cells, the apoptosis of the cells, the level of phosphorylation of Akt (p-Akt) and extracellular signal-regulated kinases (p-ERKs) and cleaved caspase-3 expression were detected by MTT, Hoechst staining and flow cytometer assays and Western blotting. Results showed that corticosterone induced cells viability loss, cell apoptosis, down-regulation of p-Akt and p-ERKs and up-regulation of cleaved caspase-3. The effects induced by corticosterone were attenuated by apelin-13 pretreatment. Furthermore, apelin-13-mediated anti-viability loss, antiapoptosis and caspase-3 suppression activities were blocked by specific inhibitors of phosphatidylinositol 3-kinase (PI3K) (LY294002) and ERKs (PD98059). The data suggest that apelin-13 protects PC12 cells from corticosterone-induced apoptosis through activating PI3K/Akt and ERKs signaling pathways.

Piromelatine ameliorates memory deficits associated with chronic mild stress-induced anhedonia in rats.

RATIONALE: Previous studies have demonstrated that piromelatine (a melatonin and serotonin 5-HT1A and 5-HT1D agonist) exerts an antidepressant activity in rodent models of acute stress and improves cognitive impairments in a rat model of Alzheimer's disease (AD). However, the role of piromelatine in chronic stress-induced memory dysfunction remains unclear. OBJECTIVE: The aim of this study was to determine whether piromelatine ameliorates chronic mild stress (CMS)-induced memory deficits and explore the underlying mechanisms. METHODS: Rats were exposed randomly to chronic mild stressors for 7 weeks to induce anhedonia (reflected by a significant decrease in sucrose intake), which was used to select rats vulnerable (CMS-anhedonic, CMSA) or resistant (CMS-resistant, CMSR) to stress. Piromelatine (50 mg/kg) was administered daily during the last 2 weeks of CMS. The tail suspension and forced swimming tests were adopted to further characterize vulnerable and resilient rats. The Y-maze and novel object recognition (NOR) tests were used to evaluate memory performance. Brain-derived neurotrophic factor (BDNF), cAMP response element-binding protein (CREB), phosphorylated CREB (pCREB), and cytogenesis were measured in the hippocampus. RESULTS: We found that only CMSA rats displayed significant increases in immobility time in the tail suspension and forced swimming tests; memory deficits in the Y-maze and NOR tests; significant decreases in hippocampal BDNF, CREB, and pCREB expression; and cytogenesis. All these anhedonia-associated effects were reversed by piromelatine. CONCLUSIONS: Piromelatine ameliorates memory deficits associated with CMS-induced anhedonia in rats and this effect may be mediated by restoring hippocampal BDNF, CREB, and cytogenesis deficits.

Autophagy is involved in the pathogenesis of experimental autoimmune neuritis in rats.

Recent studies have shown that autophagy is involved in peripheral nervous system disease. However, the role of autophagy in the pathogenesis of experimental autoimmune neuritis (EAN) remains unclear. Therefore, EAN was induced by a subcutaneous injection into both hind footpads of synthetic neuritogenic P2(57-81) peptide in male Lewis rats. The clinical evaluation was completed using a 10-point scale method. The histological alteration of sciatic nerves was analyzed by hematoxylin and eosin and luxol fast blue staining. The ultrastructure of sciatic nerves was analyzed by transmission electron microscopy. Expressions of beclin-1 and microtubule-associated protein light chain-3 (LC3) and p62/SQSTM1 were determined by western blot. 3-Methyladenine, the inhibitor of autophagy, was used in this research. Results showed that the clinical scores were significantly increased from day 6 to day 16 after immunization compared with the control group. Compared with the control group, the number of inflammatory cells and the histological score of sciatic nerves were significantly increased, expressions of beclin-1 and LC3-II and the ratio of LC3-II/LC3-I in the sciatic nerve were significantly increased, and the expression of p62 was significantly decreased in the EAN model group. Considerable double-membrane autophagosomes in axons and myelin sheaths of sciatic nerves were observed and the number of autophagosomes in axons and myelin sheaths of sciatic nerves in the EAN model group was obviously increased compared with the control group. 3-Methyladenine ameliorated the neurologic severity of EAN. Our results suggest that autophagy activity in nerve tissue of EAN rats is increased, which may be associated with the pathogenesis of EAN.

Apelin-13 Prevents the Delayed Neuropathy Induced by Tri-ortho-cresyl Phosphate Through Regulation the Autophagy Flux in Hens.

Organophosphate-induced delayed neuropathy (OPIDN) is pathologically characterized by the swollen axon containing aggregations of microtubules, neurofilaments, smooth endoplasmic reticulum and multivesicular vesicles. At present, the exact mechanism of OPIDN is unclear and the effective therapeutic methods is not available to counter this syndrome. Recent studies had shown that the autophagy was involved in OPIDN. The adipocytokine Apelin is a peptide, Apelin and its receptor are abundantly expressed in the nervous system. Recent researches illuminated that Apelin was neuroprotective factor and Apelin could regulate the autophagy in vivo and vitro model. So we investigated the effect of Apelin-13 on the OPIDN induced by Tri-ortho-cresyl phosphate (TOCP) in hens and explored the role of autophagy in Apelin-13 preventing OPIDN. Adult Roman hens were given a single dose of 750 mg/kg TOCP by gavage for 21 days to induce OPIDN, and neural dysfunction were detected, and the formation of autophagosomes in spinal cord neurons was observed by transmission electron microscopy, and the molecular markers of autophagy microtubule-associated protein light chain-3 (LC3) and the autophagy substrates p62/SQSTM1 were determined by Western blot analysis. The results demonstrated that the obvious neurological dysfunction such as hindlimb paralysis and paralysis of gait was present, the number of autophagosomes in the neurons of spinal cords was significantly increased, the level of LC3-II and p62 expressions and the ratio of LC3-II/LC3-I in spinal cords and sciatic nerve were significantly increased in the OPIDN model group compared with the control group. Compared with the OPIDN model group, the neurological dysfunction of tens was obviously reduced, the clinical signs scores was significantly decreased, the number of autophagosomes in the neurons of hen spinal cords was significantly decreased, the level of LC3-II and p62 expressions and the ratio of LC3-II/LC3-I in spinal cords and sciatic nerve were significantly decreased in Apelin-13 treatment group. Our results suggested that Apelin-13 prevented against the OPIDN induced by TOCP in hens, which the mechanism might be associated with regulation autophagy flux by Apelin-13.

[EFFECT OF HAMSTRING TENDON TRANSFECTED WITH ADENOVIRUS- MEDIATED TRANSFORMING GROWTH FACTOR ß1 GENE ON HISTOMORPHOLOGY OF TENDON-BONE INTERFACE HEALING AFTER ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION IN RABBITS].

OBJECTIVE: To investigate the effect of hamstring tendon transfected with adenovirus-mediated transforming growth factor ß1 (AdTGF-ß1) genes on the histomorphology of tendon-bone interface healing after anterior cruciate ligament (ACL) reconstruction in rabbits. METHODS: AdTGF-ß1 and AdGFP were diluted to 5 x 108 PFU/mL with DMEM. Forty-eight New Zealand white rabbits were divided into 3 groups randomly (n=16), weighing 1.6-2.5 kg for ACL reconstruction with hamstring tendon autograft. Hamstring tendon was cultured and transfected with AdTGF-ß1 (group A) and AdGFP (group B) for 12 hours before ACL reconstruction, and was cultured with DMEM in group C. After 12 hours of transfection, the expression of green fluorescence was observed in groups A and B under fluorescence microscopy; TGF-ß1 protein level was detected by ELISA in group A. At 2, 4, 8, and 12 weeks after operation, the specimens were harvested for HE and Masson staining; the number of fibroblasts was counted, and the Buark grading was used to evaluate tendon-bone interface healing. RESULTS: Green fluorescence was observed after 12 hours of transfection in groups A and B. TGF-ß1 protein level reached (221.0 ± 12.2) ng/mL at 12 hours in group A. The histological observation showed that few fibroblasts and collagen fibers were found, and Sharpey fibers appeared in group A; regular Sharpey fibers were seen in the interface, and integrity interface in some areas at 12 weeks. But fibroblasts of groups B and C were less than those of group A, with loose tendon-bone interface; no integrity interface was observed at 12 weeks. The number of fibroblasts and Buark grading of group A were significantly higher than those of groups B and C (P < 0.05), but no significant difference was found between groups B and C (P > 0.05). CONCLUSION: Hamstring tendon transfected with AdTGF-ß1 gene can promote the healing of tendon-bone interface after ACL reconstruction.

A novel melatonin agonist Neu-P11 facilitates memory performance and improves cognitive impairment in a rat model of Alzheimer' disease.

Previous studies have shown that melatonin is implicated in modulating learning and memory processing. Melatonin also exerts neuroprotective activities against Aß-induced injury in vitro and in vivo. Neu-P11 (piromelatine, N-(2-(5-methoxy-1H-indol-3-yl)ethyl)-4-oxo-4H-pyran-2-carboxamide) is a novel melatonin (MT1/MT2) receptor agonist and a serotonin 5-HT1A/1D receptor agonist recently developed for the treatment of insomnia. In the present study we firstly investigated whether Neu-P11 and melatonin enhance memory performance in the novel object recognition (NOR) task in rats, and then assessed whether Neu-P11 and melatonin improve neuronal and cognitive impairment in a rat model of Alzheimer' disease (AD) induced by intrahippocampal Aß(1-42) injection. The results showed that a single morning or afternoon administration of Neu-P11 enhanced object recognition memory measured at 4 or 24h after training. Melatonin was effective in the memory facilitating effects only when administered in the afternoon. Further results showed that intrahippocampal Aß(1-42) injection resulted in hippocampal cellular loss, as well as decreased learning ability and memory in the Y maze and NOR tasks in rats. Neu-P11 but not melatonin attenuated cellular loss and cognitive impairment in the rat AD model. The current data suggest that Neu-P11 may serve as a novel agent for the treatment of AD.

Cariporide, a specific Na/H(+) exchanger 1 blocker, inhibits neointimal proliferation induced by advanced glycation end products in a balloon injury rat model.

AIMS: The association between diabetes and neointimal expansion after vascular injury has been attributed to the accumulation of advanced glycation end products (AGEs). Here we investigated the inhibitory effect of cariporide, a specific Na(+)/H(+) exchanger 1 blocker, on neointimal proliferation induced by AGEs in a balloon injury model. METHODS: Expression of cyclooxygenase-2 (COX-2) and matrix metalloproteinase (MMP) was monitored by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. The level of reactive oxygen species (ROS) was determined by specific fluorescent probe. The phosphorylation of the nuclear factor-ĸB (NF-ĸB) system was studied by Western blot. RESULTS: Cariporide significantly suppressed AGE-induced neointimal hyperplasia, vascular smooth muscle cell (VSMC) proliferation, COX-2, MMP-2 and MMP-9 expression. In addition, cariporide decreased AGE-induced ROS, malondiadehyde level and increased the superoxide dismutase and glutathione peroxidase activity. We also found that cariporide blocked AGE-induced NF-ĸB activation and inhibitor-ĸB degradation. CONCLUSIONS: The results indicated that cariporide inhibited AGE-induced neointimal formation by suppressing the VSMC proliferation and the up-regulation of COX-2, MMP-2, MMP-9 via inhibiting ROS and NF-ĸB activation.