Simultaneous Treatment of 5-Aminosalicylic Acid and Treadmill Exercise More Effectively Improves Ulcerative Colitis in Mice.

Ulcerative colitis (UC) is characterized by continuous mucosal ulceration of the colon, starting in the rectum. 5-Aminosalicylic acid (5-ASA) is the main therapy for ulcerative colitis; however, it has side effects. Physical exercise effectively increases the number of anti-inflammatory and anti-immune cells in the body. In the current study, the effects of simultaneous treatment of treadmill exercise and 5-ASA were compared with monotherapy with physical exercise or 5-ASA in UC mice. To induce the UC animal model, the mice consumed 2% dextran sulfate sodium dissolved in drinking water for 7 days. The mice in the exercise groups exercised on a treadmill for 1 h once a day for 14 days after UC induction. The 5-ASA-treated groups received 5-ASA by enema injection using a 200 µL polyethylene catheter once a day for 14 days. Simultaneous treatment improved histological damage and increased body weight, colon weight, and colon length, whereas the disease activity index score and collagen deposition were decreased. Simultaneous treatment with treadmill exercise and 5-ASA suppressed pro-inflammatory cytokines and apoptosis following UC. The benefits of this simultaneous treatment may be due to inhibition on nuclear factor-κB/mitogen-activated protein kinase signaling activation. Based on this study, simultaneous treatment of treadmill exercise and 5-ASA can be considered as a new therapy of UC.

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-1ß, 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.

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 A2A 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 A2A receptor, 8 mg/kg 3,7-dimethyl-1-propargylxanthine (DMPX), an adenosine A2A 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.

Polydeoxyribonucleotide Ameliorates Lipopolysaccharide-Induced Lung Injury by Inhibiting Apoptotic Cell Death in Rats.

Lung injury is characterized by diffuse lung inflammation, alveolar-capillary destruction, and alveolar flooding, resulting in respiratory failure. Polydexyribonucleotide (PDRN) has an anti-inflammatory effect, decreasing inflammatory cytokines, and suppressing apoptosis. Thus, we investigated its efficacy in the treatment of lung injury, which was induced in rats using lipopolysaccharide (LPS). Rats were randomly divided into three groups according to sacrifice time, and each group split into control, lung injury-induced, and lung injury-induced + PDRN-treated groups. Rats were sacrificed 24 h and 72 h after PDRN administration, according to each group. Lung injury was induced by intratracheal instillation of LPS (5 mg/kg) in 0.2 mL saline. Rats in PDRN-treated groups received a single intraperitoneal injection of 0.3 mL distilled water including PDRN (8 mg/kg), 1 h after lung injury induction. Percentages of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive, cleaved caspase-3-, -8-, and -9-positive cells, the ratio of Bcl-2-associated X protein (Bax) to B-cell lymphoma 2 (Bcl-2), and expressions of inflammatory cytokines (tumor necrosis factor-α, interleukin-6) were decreased by PDRN treatment in the LPS-induced lung injury rats. Therefore, treatment with PDRN reduced lung injury score. This anti-apoptotic effect of PDRN can be ascribed to the enhancing effect of PDRN on adenosine A2A receptor expression. Based on these results, PDRN might be considered as a new therapeutic agent for the treatment of lung injury.

Oral mucosa stem cells alleviates spinal cord injury-induced neurogenic bladder symptoms in rats.

BACKGROUND: Spinal cord injury (SCI) deteriorates various physical functions, in particular, bladder problems occur as a result of damage to the spinal cord. Stem cell therapy for SCI has been focused as the new strategy to treat the injuries and to restore the lost functions. The oral mucosa cells are considered as the stem cells-like progenitor cells. In the present study, we investigated the effects of oral mucosa stem cells on the SCI-induced neurogenic bladder in relation with apoptotic neuronal cell death and cell proliferation. RESULTS: The contraction pressure and the contraction time in the urinary bladder were increased after induction of SCI, in contrast, transplantation of the oral mucosa stem cells decreased the contraction pressure and the contraction time in the SCI-induced rats. Induction of SCI initiated apoptosis in the spinal cord tissues, whereas treatment with the oral mucosa stem cells suppressed the SCI-induced apoptosis. Disrupted spinal cord by SCI was improved by transplantation of the oral mucosa stem cells, and new tissues were increased around the damaged tissues. In addition, transplantation of the oral mucosa stem cells suppressed SCI-induced neuronal activation in the voiding centers. CONCLUSIONS: Transplantation of oral mucosa stem cells ameliorates the SCI-induced neurogenic bladder symptoms by inhibiting apoptosis and by enhancing cell proliferation. As the results, SCI-induced neuronal activation in the neuronal voiding centers was suppressed, showing the normalization of voiding function.

Pirfenidone improves voiding function by suppressing bladder fibrosis in underactive bladder rats.

Underactive bladder (UAB), characterized by a complex set of symptoms with few treatment options, can significantly reduce the quality of life of affected people. UAB is characterized by hyperplasia and fibrosis of the bladder wall as well as decreased bladder compliance. Pirfenidone is a powerful anti-fibrotic agent that inhibits the progression of fibrosis in people with idiopathic pulmonary fibrosis. In the current study, we evaluated the efficacy of pirfenidone in the treatment of bladder fibrosis in a UAB rat model. UAB was induced by crushing damage to nerve bundles in the major pelvic ganglion. Forty-two days after surgery, 1 mL distilled water containing pirfenidone (100, 300, or 500 mg/kg) was orally administered once every 2 days for a total of 10 times for 20 days to the rats in the pirfenidone-treated groups. Crushing damage to the nerve bundles caused voiding dysfunction, resulting in increased bladder weight and the level of fibrous related factors in the bladder, leading to UAB symptoms. Pirfenidone treatment improved urinary function, increased bladder weight and suppressed the expression of fibrosis factors. The results of this experiment suggest that pirfenidone can be used to ameliorate difficult-to-treat urological conditions such as bladder fibrosis. Therefore, pirfenidone treatment can be considered an option to improve voiding function in patient with incurable UAB.

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.

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

Polydeoxyribonucleotide (PDRN), which is adenosine A2A 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 A2A 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 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)-1ß, 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.

Polydeoxyribonucleotide Attenuates Airway Inflammation Through A2AR Signaling Pathway in PM10-Exposed Mice.

PURPOSE: Inhalation of air containing high amounts of particular matter (PM) causes various respiratory disorders including asthma, chronic obstructive pulmonary disease, and lung cancer. The changes of expression of inflammatory factors by polydeoxyribonucleotide (PDRN) administration in the PM10-exposed trachea inflammation model were evaluated. METHODS: PM10 was administered to mouse trachea to induce acute inflammatory damage, and changes in inflammatory factors were observed after administration of PDRN and 3,7-dimethyl-1-propargylxanthine (DMPX) for 3 days daily. Expression of inflammatory cytokines, adenosine A2A receptor (A2AR), protein kinase A (PKA), 3΄,5΄-cyclic adenosine monophosphate responsive element binding protein (CREB) were detected by enzyme-linked immunosorbent assay, immunofluorescence, and western blot assay. RESULTS: PM-exposed trachea showed increased tumor necrosis factor (TNF)-α and interleukin (IL)-1ß expression, and expression of TNF-α and IL-1ß was inhibited by PDRN treatment in PM-exposed mice. PM-exposed trachea showed increased nuclear factor (NF)-κB phosphorylation, and phosphorylation of nuclear factor-kappa B was inhibited by PDRN treatment in PM-exposed mice. PM-exposed trachea showed increased expression of A2AR, but PDRN treatment more enhanced A2AR expression in PM-exposed mice. PKA phosphorylation was not changed and CREP phosphorylation was decreased, however PDRN treatment increased phosphorylation of PKA and CREB in PM-exposed mice. DMPX treatment blocked all the effects of PDRN on PM-exposed mice, demonstrating that the action of PDRN occurs via A2AR. CONCLUSION: PDRN treatment attenuated inflammation in the trachea of the PM10-exposed mice. This improving effect of PDRN can be ascribed to the activation of A2AR through the cAMP-PKA pathway.

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)-1ß, 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-1ß, and IL-6 were significantly enhanced by alcohol treatment. Alcohol with LPS treatment significantly enhanced concentrations of TNF-α, IL-1ß, and IL-6 more than alcohol alone treatment. Alcohol with CCL4 treatment significantly enhanced TNF-α, IL-1ß, and IL-6 concentrations more than alcohol alone treatment. Alcohol with LPS and CCL4 treatment increased TNF-α, IL-1ß, 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.

Resistance Exercise Improves Spatial Learning Ability Through Phosphorylation of 5'-Adenosine Monophosphate-Activated Protein Kinase in Parkinson Disease Mice.

PURPOSE: Exercise is a representative noninvasive treatment that can be applied to various diseases. We studied the effect of resistance exercise on motor function and spatial learning ability in Parkinson disease (PD) mice. METHODS: The rotarod test and beam walking test were conducted to evaluate the effect of resistance exercise on motor function, and the Morris water maze test was conducted to examine the effect of resistance exercise on spatial learning ability. The effect of resistance exercise on brain-derived neurotrophic factor (BDNF) and tropomyosin receptor kinase B (TrkB) expression and 5'-adenosine monophosphate-activated protein kinase (AMPK) phosphorylation was investigated by Western blot analysis. New cell generation was confirmed by immunohistochemistry for 5-bromo-2'-deoxyuridine. RESULTS: Resistance exercise improved coordination, balance, and spatial learning ability in PD mice. Resistance exercise enhanced new cell production, BDNF and TrkB expression, and AMPK phosphorylation in PD mice. The effect of such resistance exercise was similar to that of levodopa application. CONCLUSION: In PD-induced mice, resistance exercise enhanced AMPK phosphorylation to increase BDNF expression and new neuron generation, thereby improving spatial learning ability. Resistance exercise is believed to help improve symptoms of PD.

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 A2A 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.

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.

Combination Therapy With Polydeoxyribonucleotide and Pirfenidone Alleviates Symptoms of Acute Respiratory Distress Syndrome in Human Lung Epithelial A549 Cells.

PURPOSE: Acute respiratory distress syndrome (ARDS) is characterized by its acute onset of symptoms such as bilateral pulmonary infiltrates, severe hypoxemia, and pulmonary edema. Many patients with ARDS survive in the acute phase, but then die from significant lung fibrosis. METHODS: The effect of combination therapy with polydeoxyribonucleotide (PDRN) and pirfenidone on ARDS was investigated using human lung epithelial A549 cells. ARDS environment was induced by treatment with lipopolysaccharide and transforming growth factor (TGF)-ß. Enzyme-linked immunoassay for connective tissue growth factor (CTGF) and hydroxyproline were conducted. Western blot for collagen type I, fibroblast growth factor (FGF), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 was performed. RESULTS: In this study, 8-µg/mL PDRN enhanced cell viability. Combination therapy with PDRN and pirfenidone and pirfenidone monotherapy suppressed expressions of CTGF and hydroxyproline and inhibited expressions of collagen type I and FGF. Combination therapy with PDRN and pirfenidone and PDRN monotherapy suppressed expression of TNF-α and IL-1ß. CONCLUSION: The combination therapy with PDRN and pirfenidone exerted stronger therapeutic effect against lipopolysaccharide and TGF-ß-induced ARDS environment compared to the PDRN monotherapy or pirfenidone monotherapy. The excellent therapeutic effect of combination therapy with PDRN and pirfenidone on ARDS was shown by promoting the rapid anti-inflammatory effect and inhibiting the fibrotic processes.

Polydeoxyribonucleotide Ameliorates Inflammation and Apoptosis in Achilles Tendon-Injury Rats.

PURPOSE: Adenosine A2A receptor agonist polydeoxyribonucleotide (PDRN) possesses an anti-inflammatory effect and suppress apoptotic cell death in several disorders. In this current study, the effect of PDRN on inflammation and apoptosis in rats with Achilles tendon injury was investigated. METHODS: von Frey filament test and plantar test were conducted for the determination of pain threshold. Analysis of histological alterations was conducted by hematoxylin and eosin staining. Immunohistochemistry for cleaved caspase-3-positive cells and cleaved caspase-9-positive cells was done. Enzyme-linked immunoassay was used to detect the concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and cyclic adenosine-3',5'-monophosphate (cAMP). Western blot was conducted to detect the protein levels of cAMP response element-binding protein (CREB), protein kinase A (PKA), Bcl-2-associated X (Bax), and B-cell lymphoma 2 (Bcl-2). RESULTS: PDRN treatment relieved mechanical allodynia and alleviated thermal hyperalgesia after Achilles tendon injury. TNF-α and IL-6 concentrations were decreased by PDRN application. PDRN injection significantly enhanced cAMP concentration and phosphorylated CREB versus CREB ratio, showing cAMP-PKA-CREB pathway was activated by PDRN application. PDRN treatment inhibited percentages of cleaved caspase-3-positive cells and caspase-9-posiive cells and the suppressed Bax versus Bcl-2 ratio in Achilles tendon injury rats. CONCLUSION: PDRN is probably believed to have a good effect on pain and inflammation in the urogenital organs. PDRN may be used as a new treatment for Achilles tendon injury.

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 A2A 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 A2A 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 A2A 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.

Polydeoxyribonucleotide Exerts Therapeutic Effect by Increasing VEGF and Inhibiting Inflammatory Cytokines in Ischemic Colitis Rats.

Ischemic colitis is resulted from an inadequate blood supply to a segment or entire colon. Polydeoxyribonucleotide (PDRN), extracted from salmon sperm, has been reported to exert anti-inflammatory and anti-ischemic effects through the adenosine A2A receptor (A2AR). We investigated whether PDRN possesses therapeutic effectiveness on ischemic colitis rats. Ischemic colitis was induced by selective devascularization. The skin temperature on the ischemic colitis-induced region was determined. To assess the colonic damage score and collagen deposition, colonic tissue sections were stained with hematoxylin and eosin (H&E), and Masson trichrome staining was performed. Western blot analysis for A2AR, vascular endothelial growth factor (VEGF), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and IL-6, Bax, Bcl-2, and extracellular signal-regulated kinase 1/2 (ERK1/2) was performed. Skin temperature was increased and mucosal damage and collagen deposition were observed in the affected colonic tissues in the ischemic colitis rats. Expressions of inflammatory cytokines (TNF-α, IL-1ß, and IL-6) and inflammatory mediator (COX-2) were upregulated in the ischemic colitis rats. Apoptosis was increased by decreasing the ratio of Bcl-2 to Bax and by suppressing the phosphorylated form of ERK1/2 expression in the ischemic colitis rats. Treatment with PDRN alleviated mucosal damage reduced the expressions of inflammatory cytokines and COX-2 and inhibited apoptosis in the ischemic colitis rats. PDRN treatment more enhanced the expressions of A2AR and VEGF in the ischemic colitis rats. PDRN showed therapeutic effectiveness on ischemic colitis by increasing VEGF expression and inhibiting inflammatory cytokines and COX-2 through enhancing A2AR expression.

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.