Polydeoxyribonucleotide ameliorates alcoholic liver injury though suppressing phosphatidylinositol 3-kinase/protein kinase B signaling pathway in mice

Polydeoxyribonucleotide (PDRN), which is adenosine A_2A receptor agonist, facilitates healing and inhibits inflammation and apoptosis. The effect of PDRN on alcoholic liver injury (ALI) was evaluated focusing on the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. The mice were given daily oral administration of 50% ethanol at a dose of 4 g/kg during 8 weeks. After 4 weeks of alcohol intake, 200 μL of normal saline containing 8-mg/kg PDRN was intraperitoneally administered 3 times a week for 4 weeks. To determine whether the action of PDRN occurs through the adenosine A_2A receptor, 8-mg/kg 3,7-dimethyl-1-propargylxanthine (DMPX) with PDRN was treated. The concentration of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was detected. For liver histopathological score, hematoxylin and eosin staining was conducted. Enzyme-linked immunoassay was used to measure cyclic adenosine-3',5'-monophosphate (cAMP) concentration. PI3K and Akt expression was determined using Western blot analysis. In the results, PDRN treatment suppressed AST and ALT level in serum and liver tissue, and improved damaged liver tissue and decreased histological score. PDRN application inhibited the expression of phosphorylated PI3K/Akt signaling pathway. The increasing effect of PDRN on cAMP level ats as a mechanism for ALI treatment. Co-treatment of DMPX with PDRN did not reduce apoptosis, causing no improvement in liver function. As a result of this experiment, PDRN has the potential to be selected as a therapeutic agent for ALI.

Treadmill exercise ameliorates ethanol with lipopolysaccharide and carbon tetrachloride-mediated liver injury in mice

We reported that application of ethanol with lipopolysaccharide (LPS) and carbon tetrachloride (CCl₄) enhanced alanine aminotransferase (ALT) and aspartate aminotransferase (AST) level. In the current experiment, the protective effect of treadmill running on liver injury caused by ethanol with LPS and CCl₄ in mice was studied. Liver injury severity was determined by measuring ALT and AST level in the blood. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, immunohistochemistry for caspase-3, and Western blotting for Bcl-2-associated X protein (Bax) and B-cell lymphoma 2 (Bcl-2) were performed to indicate hepatocyte apoptosis. In addition, to understand the mechanism, 5′-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation was studied by Western blotting. Treadmill exercise ameliorated ethanol with LPS and CCl₄-mediated elevation of ALT and AST level. Treadmill exercise suppressed ethanol with LPS and CCl₄-mediated elevation of the TUNEL-positive cell number and cleaved caspase-3 expression. Treadmill exercise suppressed ethanol with LPS and CCl₄-mediated elevation of Bax expression and increased Bcl-2 expression suppressed by application of ethanol with LPS and CCl₄. Treadmill exercise enhanced AMPK phosphorylation which was suppressed by application of ethanol with LPS and CCl₄. Treadmill exercise has the effect of reducing liver damage caused by alcohol and or drug addiction.

Study on the pathogenesis of liver injury caused by alcohol and drugs

In the present study, alcohol, lipopolysaccharide (LPS), and carbon tetrachloride (CCL₄) were administered to experimental mice. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 concentrations, and collagen type 1alpha (COL-1A) and fibronectin expressions were measured to evaluate pathophysiology of liver injury. Levels of ALT and AST were significantly increased by alcohol treatment. Alcohol with LPS treatment increased ALT and AST levels more than alcohol alone treatment, but it was not statistically significant. Alcohol with CCL₄ treatment significantly increased ALT and AST levels more than alcohol alone treatment. Alcohol with LPS and CCL₄ treatment significantly increased ALT and AST levels more than alcohol with CCL₄ treatment. Concentrations of TNF-α, IL-1β, and IL-6 were significantly enhanced by alcohol treatment. Alcohol with LPS treatment significantly enhanced concentrations of TNF-α, IL-1β, and IL-6 more than alcohol alone treatment. Alcohol with CCL₄ treatment significantly enhanced TNF-α, IL-1β, and IL-6 concentrations more than alcohol alone treatment. Alcohol with LPS and CCL₄ treatment increased TNF-α, IL-1β, and IL-6 concentrations more than alcohol with CCL₄ treatment, but it was not statistically significant. COL-1A and fibronectin expressions were significantly increased by alcohol treatment. Alcohol with LPS treatment significantly increased COL-1A and fibronectin expressions more than alcohol alone treatment. Alcohol with CCL₄ treatment significantly increased COL-1A and fibronectin expressions more than alcohol alone treatment. Alcohol with LPS and CCL₄ treatment increased COL-1A and fibronectin expressions more than alcohol with CCL₄ treatment, but it was not statistically significant.

Treadmill exercise ameliorates impairment of spatial learning memory in pups born to old and obese mother rats

Memory state of rat pups born to old and obese mother rats and the effect of a treadmill running of mother rats on the memory of rat pups were studied. The radial 8-arm maze test was performed to detect spatial learning memory, and the level of tumor necrosis factor-α, interleukin (IL)-1β, and IL-6 in the hippocampus was measured by enzyme-linked immunoassay. Western blotting was performed for the expression of nuclear factor kappa-light-chain-enhancer (NF-κB), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκB-α), B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), matrix metalloproteinase (MMP)-9, and immunohistochemistry for caspase-3 was conducted. The newborn rats were classified into following groups: pups born to old mother rats, pups born to old mother rats with exercise, pups born to old and obese mother rats, and pups born to old and obese mother rats with exercise. Exercise of mother ameliorated spatial learning memory impairment, inhibited proinflammatory cytokines production, NF-κB expression, and IκB-α phosphorylation of the pups born to old and obese mother rats. Maternal exercise suppressed Bax expression, the number of caspase-3, the level of MMP-9, and enhanced Bcl-2 expression of the pups born to old and obese mother rats. When the maternal exercise was performed, the impairment of spatial learning memory in pups was ameliorated. Therefore, it can be seen that exercise during pregnancy of older and obese mothers is an important factor in fetal health management.

Adenosine A2A receptor agonist polydeoxyribonucleotide ameliorates short-term memory impairment by suppressing cerebral ischemia-induced inflammation via MAPK pathway

Cerebral ischemia causes tissue death owing to occlusion of the cerebral blood vessels, and cerebral ischemia activates mitogen-activated protein kinase (MAPK) and induces secretion of pro-inflammatory cytokines. Adenosine A2A receptor agonist, polydeoxyribonucleotide (PDRN), suppresses the secretion of pro-inflammatory cytokines and exhibits anti-inflammatory effect. In the current study, the therapeutic effect of PDRN on cerebral ischemia was evaluated using gerbils. For the induction of cerebral ischemia, the common carotid arteries were exposed, and then aneurysm clips were used to occlude the common carotid arteries bilaterally for 7 minutes. In the PDRN-treated groups, the gerbils were injected intraperitoneally with 0.3 mL of saline containing 8 mg/kg PDRN, per a day for 7 days following cerebral ischemia induction. In order to confirm the participation of the adenosine A2A receptor in the effects mediated by PDRN, 8 mg/kg 7-dimethyl-1-propargylxanthine (DMPX), adenosine A2A receptor antagonist, was treated with PDRN. In the current study, induction of ischemia enhanced the levels of pro-inflammatory cytokines and increased phosphorylation of MAPK signaling factors in the hippocampus and basolateral amygdala. However, treatment with PDRN ameliorated short-term memory impairment by suppressing the production of pro-inflammatory cytokines and inactivation of MAPK signaling factors in cerebral ischemia. Furthermore, PDRN treatment enhanced the concentration of cyclic adenosine-3,5'-monophosphate (cAMP) as well as phosphorylation of cAMP response element-binding protein (p-CREB). Co-treatment of DMPX and PDRN attenuated the therapeutic effect of PDRN on cerebral ischemia. Based on these findings, PDRN may be developed as the primary treatment in cerebral ischemia.

[Research advances on mechanism of exosomes derived from adipose derived stem cells in the treatment of chronic wounds]

Exosomes are a kind of membrane vesicle with a diameter of 30-150 nm. It is formed by the budding of multiple vesicles in cells, which can fuse with the cell membrane and be released into the extracellular matrix. Adipose derived stem cells (ADSCs) have the potential of self-renewal and multi-directional differentiation. They can transport the active substance, regulate the inflammatory response, cell migration, proliferation, differentiation and angiogenesis via the action of paracrine exosomes, so as to enhance the ability of wound repair, promote wound healing, and inhibit the formation of scars. Chronic wounds refer to the wounds that can not reach the anatomic and functional integrity through the normal, orderly, and timely repair process, and the course of the wound healing is more than 4 weeks. At present, there are various treatment methods for chronic wounds, among which ADSCs, although showing a good application prospect, have some limitations due to ethical issues, while exosomes can avoid this problem. This article reviews the treatment of chronic wounds with ADSC exosomes.

Adenosine A2A Receptor Agonist Polydeoxyribonucleotide Alleviates Interstitial Cystitis-Induced Voiding Dysfunction by Suppressing Inflammation and Apoptosis in Rats

Background

Interstitial cystitis (IC) is a chronic disorder that indicates bladder-related pain or discomfort. Patients with IC often experience urination problems, such as urinary frequency and urgency, along with pain or discomfort in the bladder area. Therefore, new treatments based on IC etiology are needed. Polydeoxyribonucleotide (PDRN) is a biologic agonist of the adenosine A_2A receptor, and PDRN has anti-inflammatory effect and inhibits apoptosis. In the current study, the effect of PDRN on cyclophosphamide-induced IC animal model was investigated using rats.

Methodology

To induce the IC animal model, 75 mg/kg of cyclophosphamide was injected intraperitoneally once every 3 days for 10 days. The rats in the PDRN-treated groups were intraperitoneally injected with 0.5 mL physiological saline containing 8 mg/kg PDRN, once a day for 10 days after IC induction.

Results

Induction of IC by cyclophosphamide injection caused voiding dysfunction, bladder edema, and histological damage. Cyclophosphamide injection increased secretion of pro-inflammatory cytokines and enhanced apoptosis. In contrast, PDRN treatment alleviated voiding dysfunction, bladder edema, and histological damage. Secretion of pro-inflammatory cytokines and expressions of apoptotic factors were suppressed by PDRN treatment. These changes indicate that treatment with PDRN improves voiding function by ultimately promoting the repair of damaged bladder tissue.

Conclusion

The conclusion of this experiment suggests the possibility that PDRN could be used as an effective therapeutic agent for IC.

MiR-195 promotes myocardial fibrosis in MI rats via targeting TGF-β1/Smad

The aim of this study was to investigate the effect of micro ribonucleic acid (miR)-195 on myocardial infarction (MI) in rats via regulating the transforming growth factor-β1 (TGF-β1)/Smad signaling pathway. A total of 36 Sprague-Dawley rats were randomly divided into a normal group (n=12), a model group (n=12) and an miR-195 antagomir group (n=12). In the normal group, the heart was exposed only, and normal saline was intraperitoneally injected after operation. In the model group, the acute MI model was established. In the miR-195 antagomir group, the acute MI model was also established, and miR- 195 antagomir was intraperitoneally injected. The samples were collected at 2 weeks after surgery. Then cardiac function was detected via echocardiography, and the morphology of heart tissues was observed via hematoxylin and eosin (H&E) staining. Moreover, the expression of Collagen I was determined using immunohistochemistry, the protein expressions of TGF-β1, Smad3 and Smad7 were detected using Western blotting, and the expression of miR-195 was detected via quantitative polymerase chain reaction (qPCR). It was found by echocardiography that, compared with those in the normal group, left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) significantly declined, while left ventricular end-diastolic diameter (LVDd) and left ventricular end-systolic diameter (LVDs) significantly rose in the other two groups (P<0.05). In comparison with the model group, the miR-195 antagomir group had significantly increased LVEF and LVFS, and significantly decreased LVDd and LVDs (P<0.05). The immunohistochemistry results showed that the mean optical density of tissues with positively expressed Collagen I was obviously higher in the other two groups than that in the normal group (P<0.05), while it was obviously lower in the miR-195 antagomir group than that in the model group (P<0.05). According to the results of Western blotting, the protein expressions of TGF-β1 and Smad3 were evidently increased, while the protein expression of Smad7 was evidently decreased in the other two groups compared with those in the normal group (P<0.05). The opposite results were found in the miR-195 antagomir group compared with those in the model group (P<0.05). The results of qPCR manifested that the expression of miR-195 was markedly higher in the other two groups than that in the normal group (P<0.05), while it was markedly lower in the miR-195 antagomir group than in the model group (P<0.05). Moreover, it was observed using H&E staining that the myocardial fibers in the normal group had normal arrangement and intact structure, without obvious morphological abnormalities. In the model group, the myocardial fibers were arranged disorderly, and there were massive proliferating fibrous tissues, with a high degree of fibrosis. In themiR-195 antagomir group, the myocardial fibers were damaged and arranged less disorderly, and proliferation and fibrosis could be seen in some fibrous tissues, but to a lesser extent than the model group. In conclusion, miR-195 promotes myocardial fibrosis in MI rats via up-regulating the TGF-β1/Smad signaling pathway.

Polydeoxyribonucleotide Exerts Protective Effect Against CCl4-Induced Acute Liver Injury Through Inactivation of NF-κB/MAPK Signaling Pathway in Mice

Acute liver injury (ALI) causes life-threatening clinical problem, and its underlying etiology includes inflammation and apoptosis. An adenosine A_2A receptor agonist, polydeoxyribonucleotide (PDRN), exhibits anti-inflammatory and anti-apoptotic effects by inhibiting the secretion of pro-inflammatory cytokines. In the current study, the protective effect of PDRN against carbon tetrachloride (CCl₄)-induced ALI was investigated using mice. For the induction of ALI, mice received intraperitoneal injection of CCl₄ twice over seven days. Mice from the PDRN-treated groups received an intraperitoneal injection of 200 μL saline containing PDRN (8 mg/kg), once a day for seven days, starting on day 1 after the first CCl₄ injection. In order to confirm that the action of PDRN occurs through the adenosine A_2A receptor, 8 mg/kg 3,7-dimethyl-1-propargylxanthine (DMPX), an adenosine A_2A receptor antagonist, was treated with PDRN. Administration of CCl₄ impaired liver tissue and increased the liver index and histopathologic score. The expression of pro-inflammatory cytokines was increased, and apoptosis was induced by the administration of CCl₄. Administration of CCl₄ activated nuclear factor-kappa B (NF-κB) and facilitated phosphorylation of signaling factors in mitogen-activated protein kinase (MAPK). In contrast, PDRN treatment suppressed the secretion of pro-inflammatory cytokines and inhibited apoptosis. PDRN treatment inactivated NF-κB and suppressed phosphorylation of signaling factors in MAPK. As a result, liver index and histopathologic score were reduced by PDRN treatment. When PDRN was treated with DMPX, the anti-inflammatory and anti-apoptotic effect of PDRN disappeared. Therefore, PDRN can be used as an effective therapeutic agent for acute liver damage.

Attenuation effect of polydeoxyribonucleotide on inflammatory cytokines and apoptotic factors induced by particulate matter (PM10) damage in human bronchial cells

Particulate matter (PM) of 10-μm-sized fine dust in the air penetrates the respiratory tract and contributes to the increasing incidence of various lung diseases, but its definite mechanism is not known. Recently, polydeoxyribonucleotide (PDRN) has been shown to have anti-inflammatory and regenerative effects in various tissues. However, the bronchial-related mechanism is not well-understood. Hence, this experiment is intended to demonstrate the beneficial effect of PDRN administration on PM10-induced injury in human bronchial-derived NCI-H358 cells. To confirm the protective effect of PDRN, PM10 was applied after PDRN pretreatment to confirm changes in NCI-H358 cells. Experiments were conducted to measure cell survival, cytotoxicity, inflammation, and apoptotic factor changes. WST-8 assay was used to confirm cell viability, and lactate dehydrogenase assay was used to obtain cytotoxicity. In addition, changes in inflammatory cytokines and apoptotic factors were confirmed by enzyme-linked immunosorbent assay and Western blot. Decreased cell viability and increased cytotoxicity, inflammatory cytokines, and apoptotic factors were observed after exposure to PM10. However, pretreatment with PDRN enhanced cell viability and reduced cytotoxicity. In addition, the expression of inflammatory cytokines such as tumor necrosis factor-α, interleukin-6 (IL-6), and IL-1β, and cell death factors such as Apaf-1, cyt c, caspase-3, caspase-9, Bid, and Bax/Bcl-2 ratio were decreased by PDRN administration in PM10-exposed NCI-H358 cells. PDRN, an A2AR agonist, affects cAMP activation and regulation of phosphorylation of PKA and CREB. In addition, treatment with A2AR antagonist 3,7-dimethyl-1-propargylxanthine significantly blocked PDRN's effect. These anti-cytotoxicity, anti-inflammation, and anti-apoptosis effects of PDRN can be attributed to the adenosine A2AR enhancing effect on PM10-exposed bronchial cells.

[Meta-analysis of the effects of dexmedetomidine combined with ketamine during dressing changes in burn patients]

Objective: To systematically evaluate the safety and efficacy of dexmedetomidine combined with ketamine during dressing changes in burn patients using meta-analysis. Methods: Foreign language databases including PubMed, Cochrane Central, Embase, and Web of Science were searched with the terms of " burns, dexmedetomidine, ketamine, and dressing" , and Chinese databases including Chinese Journal Full-Text Database, Wanfang Data, and China Academic Journal Network Publishing Database were searched with the terms in Chinese version of ",,,,," to retrieve the publicly published randomized controlled trials on the application of dexmedetomidine combined with ketamine for sedation and analgesia during dressing changes in burn patients from the establishment of each database to March 2019. The outcome indexes included systolic blood pressure at 5 minutes after administration, arousal restlessness score, ketamine dosage, dressing change time, body movement/recovery time, pain score, Ramsay sedation scores at 10 minutes after the start of dressing change and 1 hour after dressing change, physician satisfaction score, neuropsychological symptoms, nausea and vomiting times, nausea and vomiting score. RevMan 5.3 and Stata 14.0 statistical software were used to conduct a meta-analysis of eligible studies. Results: A total of 396 burn patients were included in 7 articles, including 198 patients in dexmedetomidine+ ketamine group who received dexmedetomidine and ketamine for sedation and analgesia, and 198 patients in ketamine alone group who received ketamine alone for sedation and analgesia. The bias risks of the seven studies included were uncertain. Compared with those of ketamine alone group, the systolic blood pressure at 5 minutes after administration, arousal restlessness score, nausea and vomiting score of patients in dexmedetomidine+ ketamine group were significantly decreased, with standardized mean differences of -13.89, -0.84, and -0.99 (95% confidence interval=-20.89--6.89, -1.17--0.52, -1.31--0.68, P<0.01), the Ramsay sedation score at 10 minutes after the start of dressing change and that at 1 hour after dressing change were significantly increased, with standardized mean differences of 1.53 and 0.72 (95% confidence interval=1.05-2.02, 0.13-1.31, P<0.05 or P<0.01), and the number of neuropsychological symptom and number of nausea and vomiting were significantly reduced, with relative risks of 0.20 and 0.16 (95% confidence interval=0.07-0.58, 0.05-0.58, P<0.01). The patients in the two groups were similar in ketamine dosage, dressing change time, body movement/recovery time, pain score, and physician satisfaction score. There was no publication bias in dressing change time or ketamine dosage (P>0.05), while the other indexes might have publication bias (P<0.05). Conclusions: Compared with ketamine alone, combination of dexmedetomidine and ketamine during dressing changes in burn patients can reduce the occurrence of restlessness, nausea and vomiting, neuropsychological symptoms, and other complications, better stabilize blood pressure, and enhance sedation effect.

Polydeoxyribonucleotide ameliorates lipopolysaccharide-induced acute lung injury via modulation of the MAPK/NF-κB signaling pathway in rats

Acute lung injury (ALI) is characterized by disruption of the alveolar-capillary membrane resulting in pulmonary edema and accumulation of associated proteinaceous alveolar exudate. Initiation of ALI upregulates tumor necrosis factor-α (TNF-α), which activates nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPK) that induce various pro-inflammatory mediators. Polydexyribonucleotide (PDRN) is an adenosine A_2A receptor agonist that exerts anti-inflammatory effects by suppressing the production of pro-inflammatory cytokines and apoptosis. We investigated the therapeutic efficiency of PDRN on ALI induced by lipopolysaccharide (LPS) in rats. ALI was induced by intratracheal instillation of LPS (5 mg/kg) in 200 μL saline. The PDRN treatment group received a single intraperitoneal injection of 500 μL saline including PDRN (8 mg/kg) 1 h after ALI induction. To confirm the involvement of the adenosine A_2A receptor in PDRN, 8 mg/kg 7-dimethyl-1-propargylxanthine (DMPX) was applied with PDRN treatment. Rats were then sacrificed 12 h after PDRN and DMPX treatments. Intratracheal administration of LPS caused lung tissue damage and significantly increased the lung injury scores and levels of pro-inflammatory cytokines, and apoptotic factors. In addition, MAPK/NF-κB signaling factors were increased by ALI initiation. PDRN treatment potently suppressed expressions of MAPK/NF-κB signaling factors compared to the PDRN + DMPX co-treated group. These alterations led to a reduction of pro-inflammatory cytokines, apoptotic factors, and NF-κB and MAPK signaling, which promoted the recovery of damaged lung tissue. PDRN therapy demonstrated therapeutic effects for LPS-induced ALI compared to the non-treated and DMPX-treated groups. Therefore, PDRN may be used as a therapy for initial treatment of ALI.

Evaluating the mucoprotective effect of polydeoxyribonucleotide against indomethacin-induced gastropathy via the MAPK/NF-κB signaling pathway in rats

Non-steroidal anti-inflammatory drugs (NSAIDs) cause gastric mucosal damage and gastric ulceration. Among the most commonly used NSAIDs, indomethacin upregulates mucosal tumor necrosis factor-α, which activates nuclear factor-kappa B (NF-κB), and mitogen-activated protein kinases (MAPK) to induce various pro-inflammatory mediators. Polydeoxyribonucleotide (PDRN) is an adenosine A_2A receptor agonist that exerts anti-inflammatory effects. In this study, we evaluated the efficacy of PDRN in the initial treatment of gastropathy against that of ecabet sodium and irsoglandin maleate, which are commonly used medications. The rats were administrated indomethacin once a day for 7 days after 24 h of fasting to induce gastropathy. Rats in the drug-treated groups were orally administrated 500 μl of distilled water containing the drug once daily for 7 days 1 h after indomethacin administration. Indomethacin administration caused mucosal damage and increased pro-inflammatory cytokine release. Both NF-κB and MAPK cascade factors were increased by indomethacin administration. PDRN therapy more potently suppressed the expressions of NF-κB and MAPK cascade factors compared to other drugs. The expression of cyclic adenosine-3',5'-monophosphate was also increased by PDRN treatment in the indomethacin-induced gastropathy rats. These changes led to a reduction in pro-inflammatory cytokines and apoptotic factors, which ultimately promote recovery of damaged gastric tissue. Therefore, PDRN may serve as a new therapeutic option in the initial treatment of NSAIDs-induced gastropathy.

Dexmedetomidine ameliorates memory impairment in sleep-deprived mice

The selective α2-adrenergic receptor agonist dexmedetomidine acts as an analgesic, sedative, and anesthetic adjuvant. The most common consequence of sleep deprivation is memory impairment. We investigated whether dexmedetomidine can counteract memory impairment caused by sleep deprivation and suppress the production of inflammatory factors. For inducing sleep deprivation, adult male mice were placed inside a water cage containing 15 platforms immersed in water up to 1 cm for 7 days. One day after sleep deprivation, dexmedetomidine at the respective dosage (5, 10, and 20 μg/kg) and α₂-adrenoceptor antagonist atipamezole (250 μg/kg) were intraperitoneally injected into the mice, once per day for six days. The step-down avoidance task and the Morris water maze test were performed. Western blot analysis was performed to determine the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, brain-derived neurotrophic factor (BDNF), tyrosine kinase B (TrkB), nuclear transcription factor-κB (NF-κB), inhibitor of κBα (IκBα), and ionized calcium binding adapter molecule I (Iba-1) in the hippocampus. Immunohistochemistry was performed for the determination of Ki-67 and glial fibrillary acidic protein (GFAP) expression in the hippocampal dentate gyrus. Dexmedetomidine ameliorated sleep deprivation-induced deterioration of short-term memory and spatial learning ability. Dexmedetomidine inhibited production of inflammatory mediators caused by sleep deprivation. Dexmedetomidine also prevented the decrease in BDNF, TrkB expression, and cell proliferation induced by sleep deprivation. Dexmedetomidine could be used to counteract the neuropathological effects of sleep deprivation.

[Advances in the research of heterotopic ossification caused by burns]

Heterotopic ossification is a rare complication of burns, and its incidence and risk factors are still unclear. Through summarizing the literature on heterotopic ossification caused by burns at home and abroad, the author searched for the risk factors of heterotopic ossification after burn and the new progress of its prevention and treatment. It was realized that the size, depth and healing time of burn wounds were related to heterotopic ossification; the nonsteroidal anti-inflammatory drugs, radiation therapy, and their combination therapy can be used for the prevention of heterotopic ossification; surgery is an effective means of treating heterotopic ossification.

Combination of treadmill exercise with bone marrow stromal cells transplantation activates protein synthesis-related molecules in soleus muscle of the spinal cord injured rats

The present study investigated whether treadmill exercise with bone marrow stromal cells (BMSCs) transplantation increase expression level of protein synthesis-related molecules in the soleus muscle after spinal cord injury (SCI). The spinal cord contusion injury was performed at the T9-10 level using the impactor (10 g×25 mm). BMSCs were cultured from femur and tibia of 4-week-old rats and then transplanted directly into the lesion 1-week post injury. The rats in exercise group were walking on treadmill device for 6 days per a week during 6 weeks. Prepared soleus muscles were used for examining mechanisms of protein synthesis after SCI. Myostatin induction level was increased by SCI, but BMSCs engrafting after SCI decreased compared to SCI group. Combination of treadmill exercise with BMSCs showed more potent decrement on myostatin expression. Protein kinase B (Akt) and mammalian target of rapamycin (mTOR) levels were significantly increased in SCI and BMSCs transplantation group compared to SCI group. Combination of treadmill exercise with BMSCs further facilitated expression levels of Akt and mTOR. Insulin-like growth factor-I (IGF-I) and phosphorylated cyclic adenosine monophosphate response element-binding protein (p-CREB) induction levels were more increased in SCI and BMSC transplantation group compared to SCI group. Combination of treadmill exercise with BMSCs further increased expression levels of IGF-I and p-CREB, although statistical significance was not appeared. Combining treadmill exercise with BMSCs transplantation might accelerate protein synthesis and hypertrophy in the soleus muscle after SCI through activation of IGF-I/mTOR signaling pathway.

Low-frequency electroacupncture improves locomotor function after sciatic crushed nerve injury in rats

Sciatic crushed nerve injury (SCI) causes pain-related gait and swelling in the affected limb. Electroacupuncture (EA) is a modified acupuncture technique, and analgesic effect of EA on different types of pain has been documented. Scientific functional index (SFI) is a mathematical formula to represent parameters of normal and experimental footprints. We investigated the effect of low-frequency EA on functional recovery following SCI in rats. For this study, immunohistochemistry for c-Fos in the ventral lateral periaqueductal gray (vlPAG) and paraventricular nucleus (PVN) and western blot for neurofilament (NF) and brain-derived neurotrophic factor (BDNF) in the sciatic nerve were conducted. To induce crush injury on the sciatic nerve, sciatic nerve was crushed for 30 sec using a surgical clip. The rats in the acupuncture groups received acupuncture bilaterally at respective site, once a day for 14 days. The rats in the EA group received 100-Hz electrical stimulation for 10 min once a day during 14 days. SCI decreased SFI value, in contrast, EA increased SFI value. c-Fos expression in the vlPAG and PVN was increased following SCI, in contrast, EA suppressed c-Fos expression. NF expression in the sciatic nerve was decreased by SCI, in contrast, EA increased NF expression. BDNF expression in the sciatic nerve was increased by SCI, in contrast, EA suppressed BDNF expression. In the present study, EA showed effectiveness on functional recovery from SCI.

[Current status of malaria rapid diagnostic testing strips application in primary-level healthcare providers in Jiangsu Province]

Objective: To investigate the current status of malaria rapid diagnostic test (RDT) strips application and malaria laboratory technicians' evaluation about them at primary healthcare provider level in Jiangsu Province. Methods: From November to December 2016, 878 medical institutions and 118 CDCs of city, county and township/community level in Jiangsu Province were selected as study samples using stratified random sampling method. Self-designed questionnaire was distributed to investigate the institution's malaria work task, RDT strips application and evaluation status in 2015. We also investigated the socio-demographic information and collected the RDT strips evaluation score from the malaria laboratory technicians selected from the institutions investigated (one technician from each institution). Rank sum test was performed to compare the RDT strips evaluation scores between medical institutions and CDCs, and among different medical institutions and CDCs. Results: In 2015, 405 cases of malaria were reported, 362 200 person-time of malaria blood testing task was conducted, and 100 000 RDT strips were procured and provided for healthcare providers in Jiangsu province for free. Of the 996 healthcare institutions investigated, 628 used RDT strips in the year 2015 and the median (P(25), P(75)) of RDT strips volume used in these institutions was 10 (2, 25). The volume of RDT strips used in CDCs (15 (5, 52)) was significantly higher than that in medical institutions (10 (2, 25), (Z=3.42, P=0.001)). The investigated CDCs gave higher score on RDT strips' testing time per operation (10 (8.5, 10)) than medical institutions (9(8, 10), (Z=-2.20, P=0.028)). The employers of 614 investigated malaria laboratory technicians used RDT strips in 2015. The median of the scores given by CDC malaria laboratory technicians for RDT strips in terms of testing time per operation, testing operation and results judgement difficulties were 10 (9, 10), 10 (9, 10) and 10 (9, 10), respectively, which were significantly higher than those from technicians of medical institutions (9 (8, 10), 9 (8, 10), 9 (8, 10), (Z values were -2.55, -2.97 and -2.96, respectively; P values were all less than 0.05)). Conclusion: RDT strips had been widely performed in health institutions in Jiangsu Province. The amount of RDT strips used in CDCs was significantly higher than that in medical institutions. Primary-level institutions and malaria laboratory technicians generally recognized RDT strips' advantage for application in terms of testing time and operational procedure. CDCs and malaria laboratory technicians from them gave higher regards on RDT strips in terms of testing time per operation, testing operation and results judgement difficulties compared with that of medical institutions.

Treadmill exercise with bone marrow stromal cells transplantation facilitates neuroprotective effect through BDNF-ERK1/2 pathway in spinal cord injury rats

Transplantation of bone marrow stromal cells (BMSCs) has been known as one of the effective therapeutic methods for functional recovery of spinal cord injury (SCI). Treadmill exercise also facilitates the functional recovery of SCI. Previously, we reported that combination of BMSCs transplantation with treadmill exercise potentiated the locomotor function in SCI rats. In the present study, we investigated whether recovery effect of BMSCs transplantation or treadmill exercise appears through the brain-derived neurotrophic factor (BDNF)-extracellular signal–regulated kinases 1/2 (ERK1/2) pathway. The spinal cord contusion injury was performed at the T9–T10 level using the impactor. Cultured BMSCs were transplanted directly into the lesion 1 week after SCI. Treadmill exercise was performed 6 days per a week for 6 weeks. Western blot for Bax, Bcl-2, BDNF, tyrosine kinase B (TrkB), and phosphorylated ERK1/2 (p-ERK1/2), phosphorylated JNK was performed. In the present results, combination of BMSCs transplantation with tread-mill exercise potently decreased Bax expression, potently increased Bcl-2 expression, and potently enhanced BDNF and TrkB expressions in the injured spinal cord. Combination of BMSCs transplantation with treadmill exercise further facilitated p-ERK1/2 and p-c-Jun expression levels. The present findings demonstrated the synergistic effect of treadmill exercise on neuroregenerative effect of BMSCs transplantation appeared through the activation of BDNF-ERK1/2 pathway in SCI.

Late starting treadmill exercise improves spatial leaning ability through suppressing CREP/BDNF/TrkB signaling pathway following traumatic brain injury in rats

Traumatic brain injury (TBI) causes deficit in spatial learning and memory function. Physical activity ameliorates neurological dysfunction after TBI. We investigated the effect of late starting treadmill exercise on spatial learning ability in relation with cAMP-response element binding protein (CREB)/brain-derived neurotrophic factor (BDNF) signaling pathway using TBI rats. For this study, radial 8-arm maze test, TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) staining, caspase-3 immunohistochemistry, and western blot for Bax, Bcl-2, BDNF, tyrosine kinase B (TrkB), CREB, and phosphorylated CREP (p-CREB) were performed. TBI was induced by an electromagnetic-controlled cortical impact. The rats in the exercise groups were scheduled to run on a treadmill for 30 min once a day for 8 weeks starting 3 weeks after TBI. TBI impaired spatial learning ability and increased caspase-3 expression in the hippocampal dentate gyrus. TBI enhanced Bax expression and suppressed Bcl-2 expression in the hip-pocampus. TBI increased BDNF and TrkB expressions, resulted in the enhancement of p-CREB/CREB ratio in the hippocampus. However, treadmill exercise improved spatial learning ability, decreased caspase-3 expression, suppressed Bax expression, and increased Bcl-2 expression. Treadmill exercise alleviated TBI-induced over-expression of BDNF and TrkB, which suppressed phosphorylation of CREB in the hippocampus. In the present study, late starting treadmill exercise improved spatial learning ability through suppressing TBI-induced activation of CREB/BDNF/TrkB signaling pathway after TBI.

Combination therapy with polydeoxyribonucleotide and proton pump inhibitor enhances therapeutic effectiveness for gastric ulcer in rats

AIMS

The main action of proton pump inhibitors (PPIs) is to inhibit gastric acid secretion, and PPIs are widely used to treat gastric ulcer (GU). However, if the action of promoting gastric mucosal regeneration is added, the effectiveness of GU treatment can be enhanced. Thus, in order to improve the therapeutic effect on GU, we tried to develop combination therapy promoting regeneration in injured tissue besides suppressing gastric acid secretion.

MAIN METHODS

Polydeoxyribonucleotide (PDRN) was selected to evaluate tissue regeneration, and pantoprazole was chosen as one of the PPIs. GU was induced by oral administration of indomethacin once a day for 7 days. Rats in drug-administered groups were intraperitoneally injected with 100 μL normal saline, containing each drug at the indicated concentration, once a day for 14 days after inducing GU.

KEY FINDINGS

PDRN and PPI combination therapy potently improved tissue regeneration and inhibited production of pro-inflammatory cytokines. PDRN treatment with or without PPI increased the concentration of cyclic adenosine-3,5'-monophosphate (cAMP) and the ratio of phosphorylated cAMP response element-binding protein (p-CREB) to cAMP response element-binding protein (CREB). PDRN treatment with or without PPI also increased the expressions of vascular endothelial growth factor (VEGF) and adenosine A_2A receptor.

SIGNIFICANCE

PDRN and PPI combination therapy showed more potent therapeutic effect on GU compared to the PDRN monotherapy or PPI monotherapy. The excellent therapeutic effect of PDRN and PPI combination therapy on GU appeared by promoting regeneration of damaged tissue as well as inhibiting gastric acid secretion.

Protective effect of erythropoietin against lipopolysaccharide induced inflammation and mitochondrial damage in liver

Recent studies have shown that liver dysfunction is an early event in sepsis. Pre-existing liver dysfunction is a risk factor for progression of infection to sepsis. However, the mechanism of the liver immune response in promoting sepsis and the importance of liver function are not completely understood. In the present study, we investigated the protective effect of erythropoietin (EPO) against mitochondrial dysfunction in a lipopolysaccharide (LPS)-induced sepsis model, and examined the underlying signaling mechanisms. Enzyme linked immunosorbent assay (ELISA) and reactive oxygen species (ROS) analysis were used to evaluate the levels of interleukin (IL)-1β and ROS. The effects of EPO on hepatic mitochondrial function were studied by detecting the mitochondrial DNA (mtDNA) copy number using real-time PCR (RT-PCR). To explore the mechanism of action of EPO in sepsis, protein expressions of IL-1β, caspase-1 and NLRP3 were assessed by Western blotting; liver histopathology and ultrastructure of liver mitochondria was examined by transmission electron microscopy. We found that LPS treatment increased serum IL-1β and ROS levels, the effect of which was attenuated by EPO. Moreover, LPS treatment also increased the mtDNA copy number and the protein expressions of IL-11β, caspase-1, and NLRP3, which were suppressed by EPO. Histological examination of liver showed LPS-induced cellular edema in hepatic lobules, lymphocytic infiltration and hepatocellular necrosis; these changes were also alleviated by EPO treatment. On electron microscopy, the size of hepatocellular mitochondria in the LPS group was smaller than that in the control group, and the changes were reversed by EPO in the LPS+EPO group. Our results suggest that EPO alleviated liver and mitochondrial damage induced by LPS, possibly via inhibition of NLRP3 signaling.

Age-dependent differences of treadmill exercise on spatial learning ability between young- and adult-age rats

The effect of exercise, which increases hippocampal neurogenesis and improves memory function, is well documented, however, differences in the effect of exercise on young children and adults are not yet known. In the present study, age-dependent differences of treadmill exercise on spatial learning ability between young- and adult-age rats were investigated. The rats in the exercise groups were forced to run on a motorized treadmill for 30 min once a day for 6 weeks. Radial 8-arm maze test was conducted for the determination of spatial learning ability. Cell proliferation in the hippocampal dentate gyrus was determined by 5-bromo-2′-deoxyuridine immunohistochemistry. Western blot for brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) was performed. In the present study, the number of errors in the young-age rats was effectively decreased by treadmill exercise. Hippocampal neurogenesis was more active in the young-age rats than in the adult-age rats. BDNF and TrkB expression in the hippocampus was greater in the adult-age rats than in the young-age rats. The results of this study showed that adults have excellent spatial learning abilities than children, but the improvement of exercise-induced spatial learning ability through neurogenesis is better in children.

[Recurrent syncope related to catecholaminergic polymorphic ventricular tachycardia due to de novo RyR2-R2401H mutation]

Objective: To explore the clinical and molecular genetic features of a Chinese patient with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods: Clinical data including resting electrocardiography, echocardiography and treadmill exercise testing of a patient with CPVT admitted to our department in March 2013 were analyzed, and the peripheral venous blood samples of the patient and his family members and 400 ethnicity-matched healthy controls were obtained. All exons and exon-intron boundaries of the six CPVT-related genes including RYR2, CASQ2, TRDN, CALM1, KCNJ2 and ANKB were sequenced to detect the variants related to CPVT. The relationship between the genotypes and phenotypes was analyzed to direct the target therapy. Results: Recurrent syncope induced either by exercise or extreme frightened fear was observed in this patient. There was no positive family history of syncope or sudden death. The resting electrocardiography and echocardiography of the patient were normal, while the exercise testing revealed bidirectional and polymorphic ventricular tachycardia. A cardiac ryanodine receptor gene mutation (R2401H) was identified in this patient, while this mutation was absent in his parents and sister and 400 controls. No variant was detected in the remaining five candidate genes. Treatment with high dose of metoprolol succinate (118.75 mg/d) was effective and patient was free of syncopal attack during the 2 years follow-up. Conclusion: This is the first report on RyR2-R2401H mutation in Chinese patient with CPVT, and high dose of metoptolol is the effective therapy option for CPVT related to RyR2 mutation.

Dexmedetomidine alleviates cerebral ischemia-induced short-term memory impairment by inhibiting the expression of apoptosis-related molecules in the hippocampus of gerbils

Cerebral ischemia results from cerebrovascular occlusion, which leads to neuronal cell death and eventually causes neurological impairments. Dexmedetomidine is a potent and highly selective α₂-adrenoreceptor agonist with actions such as sedation, anxiolysis, analgesia and anesthetic-sparing effects. We investigated the effect of dexmedetomidine on apoptosis in the hippocampus after transient global ischemia in gerbils. Transient global ischemia was induced by ligation of both common carotid arteries. Dexmedetomidine was administrated intraperitoneally at three respective doses (0.1, 1 and 10 µg/kg) once per day for 14 consecutive days beginning a day after surgery. Short-term memory was assessed by use of a step-down avoidance task. Apoptosis was evaluated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay, immunohistochemistry for caspase-3, and western blot analysis of Bcl-2-associated X protein, B-cell lymphoma 2, Bid, cytochrome c, apoptotic protease activating factor-1 and caspase-9 in the hippocampus. Induction of global ischemia deteriorated short-term memory by enhancing the expression of apoptosis-related molecules in the hippocampus. Treatment with dexmedetomidine suppressed the expression of apoptosis-related molecules under ischemic conditions, resulting in short-term memory improvement. Under normal conditions, dexmedetomidine exerted no significant effect on apoptosis in the hippocampus. The present results suggest that the α₂-adrenoceptor agonist dexmedetomidine may be a useful therapeutic agent for the treatment of ischemic brain diseases.

Analyzing the association between XRCC1 c.1804C>A genetic variant and lung cancer susceptibility in the Chinese population

Lung cancer is the most common cancer occurring worldwide. The human X-ray repair complementing group 1 (XRCC1) gene is one of the most important candidate genes that influence the susceptibility to lung cancer. The objective of this study was to analyze the potential association between the c.1804C>A genetic variant of XRCC1 and lung cancer susceptibility. A total of 703 subjects were recruited for this study. Genotyping of c.1804C>A genetic variant was performed using the created restriction site-polymerase chain reaction. Statistically significant differences in allele frequencies and genotype were found between lung cancer patients and cancer-free controls. The genotype AA was statistically associated with the increased risk of lung cancer when compared to the wild genotype, CC, and the carrier genotype, CA/CC (AA vs CC: OR = 2.71, 95%CI = 1.57-4.67, P < 0.001; AA vs

CA/CC

OR = 2.54, 95%CI = 1.50-4.29, P < 0.001). The allele A likely contributes to the susceptibility to lung cancer (A vs C: OR = 1.47, 95%CI = 1.17-1.84, P = 0.001). Our data indicates that the c.1804C>A genetic variant of XRCC1 is statistically associated with the susceptibility to lung cancer in the Chinese population.

Aqueous extract of Cordyceps alleviates cerebral ischemia-induced short-term memory impairment in gerbils

Cerebral ischemia is caused by reduced cerebral blood flow due to a transient or permanent cerebral artery occlusion. Ischemic injury in the brain leads to neuronal cell death, and eventually causes neurological impairments. Cordyceps, the name given to the fungi on insects, has abundant useful natural products with various biological activities. Cordyceps is known to have nephroprotective, hepatoprotective, anti-inflammatory, antioxidative, and antiapoptotic effects. We investigated the effects of Cordyceps on short-term memory, neuronal apoptosis, and cell proliferation in the hippocampal dentate gyrus following transient global ischemia in gerbils. For this study, a step-down avoidance test, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, immunohistochemistry for caspase-3 and 5-bromo-2′-de-oxyuridine, and western blot for Bax, Bcl-2, brain-derived neurotrophic factor (BDNF), and tyrosin kinase B were performed. In the present study, Cordyceps alleviated cerebral ischemia-induced short-term memory impairment. Cordyceps showed therapeutic effects through inhibiting cerebral ischemia-induced apoptosis in the hippocampus. Cordyceps suppressed cerebral ischemia-induced cell proliferation in the hippocampal dentate gyrus due to the reduced apoptotic neuronal cell death. Cordyceps treatment also enhanced BDNF and TrkB expressions in the hippocampus of ischemic gerbils. It can be suggested that Cordyceps overcomes cerebral ischemia-induced neuronal apoptosis, thus facilitates recovery following cerebral ischemia injury.

Analysis of ipsilateral and bilateral ratios in male amateur golfers

The number of injuries that force golfers to quit is also increasing. In particular, the upper body injuries are concerns for amateur golfers. This study was conducted not only to investigate muscular balance, such as ipsilateral and bilateral ratios of the upper body, but to also evaluate the possible problems of muscular joints in amateur golfers. Male golfers (n=10) and a healthy control group (n=10) were recruited for the assessment of muscular function in the upper body, which was measured by an isokinetic dynamometer at 60°/sec. The tested parts were trunk, wrist, forearm, elbow, and shoulder joints. Mann-Whitney U-test was used to evaluate the significance of the differences between groups. The ipsilateral ratios of peak torque or work per repetition (WR) of trunk flexor and extensor in the golfers were not significantly different compared to those of the control group. These results were similar to the shoulder horizontal abductor and adductor. However, there were significant differences in the ipsilateral and bilateral ratios of the wrist, forearm, and elbow joints. Especially, the WR of the wrist flexor, forearm pronator, and elbow flexor on the left side of amateur golfers showed imbalances in bilateral ratios. Moreover, the WR of the wrist and elbow flexors on the left side of amateur golfers were lower than those of the wrist and elbow extensors. Therefore, amateur golfers should strive to prevent injuries of the wrist, forearm, and elbow joints and to reinforce the endurance on those parts of the left side.

Effects of surgical and chemical castration on spatial learning ability in relation to cell proliferation and apoptosis in hippocampus

PURPOSE

Chemical castration using luteinizing hormone-releasing hormone agonists and/or anti-androgens is an alternative to surgical castration. Goserelin and bicalutamide are representative drugs used for chemical castration. The effects of chemical castration on sexual functions are well documented; however, the possibility that chemical castration might induce undesirable effects on brain functions has been raised. We investigated the effects of chemical castration and surgical castration on spatial learning ability in relation to cell proliferation and apoptosis in hippocampus.

METHODS

Bilateral orchiectomy was performed for surgical castration, and chemical castration was induced by treatment with goserelin or bicalutamide for 28 days. To find out the effects of goserelin and bicalutamide with those of orchiectomy on the spatial learning ability, radial eight-arm maze test was performed. To find out the effects of goserelin and bicalutamide with those of orchiectomy in relation to cell proliferation and apoptosis in the hippocampus, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining, and immunohistochemistry for 5-bromo-2'-deoxyuridine, doublecortin, and caspase-3 were performed. Western blot for brain-derived neurotrophic factor, tyrosine kinase receptor B, Bax, and Bcl-2 in the hippocampus was also performed.

RESULTS

Orchiectomy caused deterioration of spatial learning ability with suppression of cell proliferation and enhancement of apoptosis in the hippocampus. However, treatment with goserelin and bicalutamide had no effect on spatial learning ability. Cell proliferation and apoptosis were not altered by treatment with goserelin and bicalutamide either.

CONCLUSIONS

Surgical castration causes deterioration of spatial learning ability, while chemical castration does not impair spatial learning ability. We should find out further mechanisms affect to the relationship between androgen level and neurogenesis and neuronal apoptosis.

Treadmill exercise improves short-term memory by enhancing hippocampal cell proliferation in quinolinic acid-induced Huntington's disease rats

Huntington’s disease (HD) is an inherited genetic disorder, characterized by cognitive dysfunction and abnormal body movements called chorea. Quinolinic acid (QA) is an endogenous metabolite of tryptophan in the kynurenine pathway. QA-induced alterations are similar to the symptoms of HD patients. Physical exercise has beneficial effects on the brain functions. Exercise increases production of neurotrophic factors in the brain and improves learning ability and memory function. In the present study, we investigated the effects of treadmill exercise short-term memory on QA-induced HD rats in relation with cell proliferation. For the induction of Huntington’s animal model, 2 μL of 100 nmol QA was intrastriatal injected into the rats. The rats in the treadmill exercise groups were forced to run on a treadmill for 30 min once a day, five times a week for 2 weeks. Step-down avoidance test was conducted for the determination of short-term memory. Cell proliferation in the hippocampal dentate gyrus was determined by 5-bromo-2′-deoxyuridine (BrdU) and doublecortin (DCX) immunohistochemistry. Western blot for brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) were performed. In the present results, treadmill exercise alleviated QA-induced short-term memory impairment in HD rats. Treadmill exercise increased cell proliferation in the hippocampal dentate gyrus through enhancing BDNF expression in the HD rats. These results revealed that treadmill exercise is effective for the symptom improvement in the HD patients.

Caffeine enhances micturition through neuronal activation in micturition centers

Caffeine may promote incontinence through its diuretic effect, particularly in individuals with underlying detrusor overactivity, in addition to increasing muscle contraction of the bladder smooth muscle. Caffeine may also affect bladder function via central micturition centers, including the medial preoptic area, ventrolateral periaqueductal gray, and pontine micturition center. However, the biochemical mechanisms of caffeine in central micturition centers affecting bladder function remain unclear. In the present study, the effects of caffeine on the central micturition reflex were investigated by measuring the degree of neuronal activation, and by quantifying nerve growth factor (NGF) expression in rats. Following caffeine administration for 14 days, a urodynamic study was performed to assess the changes to bladder function. Subsequently, immunohistochemical staining to identify the expression of c‑Fos and NGF in the central micturition areas was performed. Ingestion of caffeine increased bladder smooth muscle contraction pressure and time as determined by cystometry. Expression levels of c‑Fos and NGF in all central micturition areas were significantly increased following the administration of caffeine. The effects on contraction pressure and time were the most potent and expression levels of c‑Fos and NGF were greatest at the lowest dose of caffeine. These results suggest that caffeine facilitates bladder instability through enhancing neuronal activation in the central micturition areas.

Swimming exercise ameliorates multiple sclerosis-induced impairment of short-term memory by suppressing apoptosis in the hippocampus of rats

Multiple sclerosis is one of the autoimmune diseases in the central nervous system. Multiple sclerosis occurs through multiple mechanisms, and it is also mediated in part by an apoptotic mechanism. Swimming exercise has been recommended for the prevention and treatment of chronic diseases. In the present study, we investigated the effects of swimming exercise on short-term memory in relation with apoptotic neuronal cell death in the hippocampus following induction of multiple sclerosis. For this study, step-down avoidance task, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, immunohistochemistry for caspase-3 were performed. The animal model of multiple sclerosis was made by bilateral intracerebral ventricle injection of ethidium bromide. The rats in the swimming exercise groups were forced to swim for 30 min once daily for 14 consecutive days, starting 3 days after induction of multiple sclerosis. In the present results, short-term memory was deteriorated in the multiple sclerosis-induced rats. The number of TUNEL-positive and caspase-3-positive cells in the hippocampal dentate gyrus was increased in the multiple sclerosis-induced rats. Swimming exercise alleviated multiple sclerosis-induced short-term memory impairment by suppressing apoptotic neuronal cell death in the hippocampus. These effects of swimming exercise may aid symptom relief in the incurable neurodegenerative diseases.

[Study of sesquiterpene alkaloids from Tripterygium wilfordii Hook.f]

AIM

To study the chemical composition of Tripterygium wilfordii Hook.f.

METHODS

Column chromatography was used to separate the chemical constituents. UV, IR, MS, HRMS, 1HNMR, 13CNMR (COM and OFR), 1H-1H COSY, 1H-13C COSY, 2D-NOESY and 1H-13C COLOC were used to determine the structures of the isolated constituents.

RESULTS

Two sesquiterpene alkaloids were isolated and their structures were elucidated as euonine and wilfordconine on the basis of spectral evidence.

CONCLUSION

Wilfordconine, a new sesquiterpene alkaloid, was shown to be immunosuppressive.

Wild type neu transgene counteracts mutant homologue in malignant transformation of rat Schwann cells

Mutational activation of the neu (erbB-2) receptor protein tyrosine kinase gene appears to be the triggering event in the process of oncogenesis induced by N-ethyl-N-nitrosourea (EtNU) in immature Schwann cells of the rat peripheral nervous system. Subsequent loss of the wild-type neu allele may represent a critical secondary step towards malignancy. Developmentally-regulated expression of a wild-type rat neu transgene (neu cDNA under the control of the rat Po promoter) in the Schwann cells of transgenic BDIX and Sprague-Dawley rats exposed to EtNU on postnatal day 1 results in a lower incidence of early atypical proliferates in the trigeminal nerve. Furthermore, re-introduction of the wild-type neu gene into homozygous neu mutant schwannoma cells counteracts the expression of the tumorigenic phenotype. The suppressive action of the wild-type gene over its mutationally activated oncogenic homologue underlines the critical function of the neu gene in the control of differentiation in the Schwann cell lineage, and provides evidence for the responsiveness of cellular phenotypes towards quantitative shifts in the dosage of wild-type vs mutant signal transducing molecules.

[Anti-inflammatory effect of Caragana microphylla Lam]

Caragana microphylla can antagonize the inflammation induced by carrageenin, hot water and croton oil. It can also inhibit the proliferation of granuloma, blood capillary permeability, phagocytic function of mononuclear phagocyte system, and synthesis or release of PGE2 at the inflamed part.

Schwann cell lineage-specific neu (erbB-2) gene expression in the developing rat nervous system

Initiation of oncogenesis in the immature peripheral nervous system (PNS) of rats by the DNA-reactive carcinogen N-ethyl-N-nitrosourea (EtNU) involves a specific T:A-->A:T transversion mutation at nucleotide 2012 of the neu (erbB-2) receptor tyrosine kinase gene in cells of the Schwann cell lineage. Although this mutation is invariably detected in the resulting malignant schwannomas, it is not found in EtNU-induced tumors of the central nervous system (CNS). We have evaluated expression of the neu gene in the PNS and CNS as a function of developmental stage. Cellular levels of neu mRNA and gp185neu were analyzed in the trigeminal and sciatic nerve and in brain, using a quantitative reverse transcription-polymerase chain reaction, in situ hybridization, immunocytochemistry, and fluorescence-activated cell sorting. In the PNS, expression of the neu gene is restricted to cells of the Schwann cell lineage and markedly exceeds expression in the CNS from prenatal day 20 onward. In trigeminal Schwann cells, neu mRNA is most abundant (2.8 x 10(7) copies/micrograms of RNA) on postnatal day 1, coincident with both the end of maximum mitotic activity and the "developmental window" of highest sensitivity to malignant transformation by EtNU. The subsequent decrease of neu gene expression is accompanied by decreasing proliferative activity and the onset of myelination. The level of neu gene expression may thus be critical to proliferation versus differentiation decisions in the Schwann cell lineage. EtNU-induced mutation of the neu gene in proliferative Schwann cell precursors expressing gp185neu may abrogate their responsiveness to extracellular and/or intrinsic controls, resulting in sustained proliferative activity and malignant conversion.

[Effect of expression of exogenous PDGF-A chain on growth and transformation of CHO cells]

CHO cells were transfected with plasmid pSV2-PDGF-A (containing human PDGF-A cDNA) by calcium phosphate method. Twenty transfected cell lines were obtained after G418 selection. The selected 2 cell lines At1 and Aot7), with prominent changes in morphology and growth behaviour, showed transcription of PDGF-A chain mRNA much higher than CHO cells, strong fluorescent PDGF-specific reaction, appearing that PDGF-like proteins were synthesized in cytoplasm of these cells. At1 and Aot7 cells not only had increased growth rate, but also formed large colonies in soft agar and grew into fibrosarcomas in nude mice. These results suggested that the expression of exogenous PDGF-A gene might cause the uncontrolled growth and malignant transformation of CHO cells.

[Expression of exogenous platelet-derived growth factor B chain gene in CHO cells]

CHO cells were transfected with plasmid pSM-1 (containing human c-sis cDNA) singly or co-transfected with pSV 2 neo DNA by calcium phosphate method. After low serum or G418 selection several cell lines with expression of platelet-derived growth factor (PDGF) were obtained. One among them, FB5, was of the highest PDGF expression and showed the following biological characteristics when compared with CHO cells: (1) a prominent change in morphology from spindle to round in shape: (2) increase of growth rate; (3) growth in low serum (2%) medium as a semisuspension culture; (4) growth on soft agar to larger colonies; (5) synthesis of PDGF in cytoplasm identified by immunofluorescent method; (6) the conditioned medium stimulated DNA synthesis of NRK cells; (7) RNA dot hybridization showing high transcription of PDGF mRNA; (8) southern blot showing integration of human c-sis gene was still stable after 7 months. These results indicated that intergration of exogenous c-sis gene and its high expression might cause CHO cells to high growth rate and even transformation. The establishment of this stable transformed cell line, FB5 is thought to be a good model for further study on the function of PDGF in cell growth control and cell transformation.