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1.
PLoS One ; 17(9): e0274126, 2022.
Article in English | MEDLINE | ID: mdl-36054162

ABSTRACT

This study was undertaken to investigate the inhibitory effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) on dimethylnitrosamine (DMN)-induced liver fibrosis in rats. Liver fibrosis was induced in Sprague-Dawley rats by injecting DMN intraperitoneally (at 10 mg/kg of body weight) daily for three consecutive days per week for 4 weeks. To investigate the effect of GM-CSF on disease onset, GM-CSF (50 µg/kg of body weight) was co-treated with DMN for 2 consecutive days per week for 4 weeks (4-week groups). To observe the effect of GM-CSF on the progression of liver fibrosis, GM-CSF was post-treated alone at 5-8 weeks after the 4 weeks of DMN injection (8-week groups). We found that DMN administration for 4 weeks produced molecular and pathological manifestations of liver fibrosis, that is, it increased the expressions of collagen type I, alpha-smooth muscle actin (α-SMA), and transforming growth factor-ß1 (TGF-ß1), and decreased peroxisome proliferator-activated receptor gamma (PPAR-γ) expression. In addition, elevated serum levels of aspartate aminotransferase (AST), total bilirubin level (TBIL), and decreased albumin level (ALB) were observed. In both the 4-week and 8-week groups, GM-CSF clearly improved the pathological liver conditions in the gross and histological observations, and significantly recovered DMN-induced increases in AST and TBIL and decreases in ALB serum levels to normal. GM-CSF also significantly decreased DMN-induced increases in collagen type I, α-SMA, and TGF-ß1 and increased DMN-induced decreases in PPAR-γ expression. In the DMN groups, survival decreased continuously for 8 weeks after DMN treatment for the first 4 weeks. GM-CSF showed a survival benefit when co-treated for the first 4 weeks but a marginal effect when post-treated for 5-8 weeks. In conclusion, co-treatment of GM-CSF showed therapeutic effects on DMN-induced liver fibrosis and survival rates in rats, while post-treatment efficiently blocked liver fibrosis.


Subject(s)
Dimethylnitrosamine , Transforming Growth Factor beta1 , Animals , Body Weight , Collagen Type I/metabolism , Dimethylnitrosamine/toxicity , Granulocyte-Macrophage Colony-Stimulating Factor/metabolism , Liver/metabolism , Liver Cirrhosis/chemically induced , Liver Cirrhosis/drug therapy , Peroxisome Proliferator-Activated Receptors/metabolism , Rats , Rats, Sprague-Dawley , Transforming Growth Factor beta1/metabolism
2.
Free Radic Res ; 55(11-12): 1037-1047, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34814783

ABSTRACT

We have previously shown that low-intensity ultrasound (LIUS) can modulate mitochondrial complex I activity and the generation of mitochondrial reactive oxygen species (mtROS) in PC12 cells. This study investigated the mechanism of LIUS by comparing its effect on mitochondrial dysfunction by three different pathways. LIUS was shown to reverse the effects of rotenone, a Q-site blocker, on the complex I inhibition, mtROS generation, and drop of mitochondrial membrane potential (Δψm). In contrast, common antioxidants, N-acetyl cysteine (NAC), and uric acid (UA) blocked rotenone-induced mtROS generation and Δψm drop without recovering the complex I activity, which suggested that Δψm drop is correlated with mtROS generation rather than complex I inhibition itself. Ionomycin, an ionophore for Ca2+, and L-buthionine-S,R-sulfoximine (BSO), an inhibitor of glutathione (GSH) biosynthesis, induced mtROS generation and Δψm drop without inhibiting complex I activity via different mechanisms. LIUS showed no effect on ionomycin-induced Δψm drop but showed partial inhibition on the other effects of ionomycin and BSO. These results suggest that LIUS might have redundant mechanisms but acted mainly on the complex I activity thereby modulating mtROS and Δψm levels. LIUS appeared to act on the Q-module of complex I because it showed no inhibitory effect on Zn2+, an inhibitor of the proton transporting P-module of complex I. Interestingly, pretreatment of LIUS for up to an hour in advance blocked the rotenone effect as efficiently as the co-treatment. Further studies are needed to reveal the exact mechanism of LIUS to inhibit complex I activity.


Subject(s)
Mitochondria , Rotenone , Animals , Glutathione/metabolism , Ionomycin/metabolism , Mitochondria/metabolism , PC12 Cells , Rats , Reactive Oxygen Species/metabolism , Rotenone/pharmacology
3.
Biol Pharm Bull ; 42(12): 1988-1995, 2019.
Article in English | MEDLINE | ID: mdl-31787714

ABSTRACT

Rich in bioactive substances such as amino acids and peptides, Laennec (human placenta hydrolysate) has been widely used to control various types of musculoskeletal pain. However, the effects of Laennec on tendon and ligament injuries are not clearly understood. In the present study, Laennec was tested to identify its in vivo effects on ligament injury in an animal model and its in vitro effects on tendon-derived fibrocytes. A total of 99 Sprague Dawley rats were divided into the negative control (normal) group (n = 11) and the ligament injury group (n = 88). The ligament injury group was subdivided into normal saline-treated group, Laennec-treated group, polydeoxyribonucleotide-treated group, and 20% dextrose-treated group. Ligaments were collected at 1 week and 4 weeks after treatment. Histologic and biomechanical properties were analyzed. In vitro effects of Laennec and polydeoxyribonucleotide on fibrocytes were also analyzed. Although all other treatment groups showed increased inflammatory cells, the Laennec-treated group maintained cell counts and activated macrophage levels that were similar to the normal group. Unlike the saline-treated group and dextrose-treated group, the Laennec-treated group had low levels of degenerative changes at 4 weeks after treatment. Supportively, in vitro results showed that the Laennec-treated group had increased collagen type I, scleraxis (Scx) and tenomodulin (Tnmd) expression (p < 0.05). Our study demonstrates that Laennec treatment enhances wound healing of damaged ligament by suppressing immune responses and reducing degenerative changes of damaged ligament. In addition, we found that Laennec induces the gene expression of type I collagen, Scx and Tnmd in fibrocytes, suggesting that Laennec may facilitate regeneration of damaged ligaments. Therefore, we expect that Laennec can be a useful drug to treat injured ligament.


Subject(s)
Complex Mixtures/pharmacology , Ligaments/drug effects , Ligaments/injuries , Placenta/chemistry , Achilles Tendon/cytology , Animals , Female , Humans , Ligaments/immunology , Ligaments/physiology , Macrophages/drug effects , Macrophages/immunology , Male , Pregnancy , Rats, Sprague-Dawley , Tensile Strength
4.
Can J Neurol Sci ; 45(6): 675-681, 2018 11.
Article in English | MEDLINE | ID: mdl-30430968

ABSTRACT

BACKGROUND: We have previously shown that low-intensity ultrasound (LIUS), a noninvasive mechanical stimulus, inhibits brain edema formation induced by oxygen and glucose deprivation (OGD) or treatment with glutamate, a mediator of OGD-induced edema, in acute rat hippocampal slice model in vitro. METHODS: In this study, we treated the rat hippocampal slices with N-methyl-d-aspartic acid (NMDA) or (S)-3,5-dihydroxyphenylglycine (DHPG) to determine whether these different glutamate receptor agonists induce edema. The hippocampal slices were then either sonicated with LIUS or treated with N-methyl-d-aspartic acid receptor (NMDAR) antagonists, namely, MK-801 and ketamine, and observed their effects on edema formation. RESULTS: We observed that treatment with NMDA, an agonist of ionotropic glutamate receptors, induced brain edema at similar degrees compared with that induced by OGD. However, treatment with DHPG, an agonist of metabotropic glutamate receptors, did not significantly induce brain edema. Treatment with the NMDAR antagonists MK-801 or ketamine efficiently prevented brain edema formation by both OGD and NMDA in a concentration-dependent manner. N-Methyl-d-aspartic acid-induced brain edema was alleviated by LIUS in an intensity-dependent manner when ultrasound was administered at 30, 50, or 100 mW/cm2 for 20 minutes before the induction of the edema. Furthermore, LIUS reduced OGD- and NMDA-induced phosphorylation of NMDARs at Y1325. CONCLUSION: These results suggest that LIUS can inhibit OGD- or NMDA-induced NMDAR activation by preventing NMDAR phosphorylation, thereby reducing a subsequent brain edema formation. The mechanisms by which LIUS inhibits NMDAR phosphorylation need further investigation.


Subject(s)
Excitatory Amino Acid Antagonists/pharmacology , N-Methylaspartate/pharmacology , Receptors, N-Methyl-D-Aspartate/metabolism , Ultrasonography , Animals , Glucose/metabolism , Glutamic Acid/metabolism , Hippocampus/metabolism , Hippocampus/physiopathology , Male , Rats, Sprague-Dawley , Receptors, Amino Acid/drug effects , Receptors, Amino Acid/metabolism , Receptors, N-Methyl-D-Aspartate/drug effects , Ultrasonography/adverse effects
5.
Ultrasound Med Biol ; 44(3): 647-656, 2018 03.
Article in English | MEDLINE | ID: mdl-29307443

ABSTRACT

Diabetic retinopathy (DR) is a severe micro-vascular complication of diabetes. High glucose (HG)-evoked nitric oxide (NO) production mediated by increased oxidative stress is a key factor in DR pathogenesis. In this study, we examined whether low-intensity ultrasound (LIUS) stimulation can reduce HG-induced NO generation. We determined that LIUS stimulation decreased the HG-induced NO generation possibly via inhibition of reactive oxygen species (ROS) and subsequently diminished the associated pro-inflammatory pathway involving the induced expression of inducible nitric oxide synthase, cyclooxygenase-2 and vascular endothelial growth factor. In addition, we determined that LIUS stimulation reduced the quantity of NO produced by N-acetylcysteine, which was not mediated by ROS. These results indicate that LIUS can inhibit both ROS-dependent and -independent NO generation processes in ARPE-19 cells. We envision LIUS as a potential therapeutic alternative to treat DR. Further studies are required to understand the underlying mechanism of the LIUS-induced reduction of NO generation for DR therapy.


Subject(s)
Epithelial Cells/metabolism , Nitric Oxide/metabolism , Retinal Pigments/metabolism , Ultrasonics/methods , Blotting, Western , Cells, Cultured , Humans
6.
Mol Neurobiol ; 54(8): 6235-6244, 2017 10.
Article in English | MEDLINE | ID: mdl-27714630

ABSTRACT

Many studies have shown that mitochondrial dysfunction and the subsequent oxidative stress caused by excessive reactive oxygen species (ROS) generation play a central role in the pathogenesis of Parkinson's disease (PD). We have previously shown that low-intensity ultrasound (LIUS) could reduce ROS generation by L-buthionine-(S,R)-sulfoximine (BSO) in retinal pigment epithelial cells. In this study, we studied the effects of LIUS stimulation on the ROS-dependent α-synuclein aggregation in 1-methyl-4-phenylpyridinium ion (MPP+)-treated PC12 cells. We found that LIUS stimulation suppressed the MPP+-induced ROS generation and inhibition of mitochondrial complex I activity in PC12 cells in an intensity-dependent manner at 30, 50, and 100 mW/cm2. Furthermore, LIUS stimulation at 100 mW/cm2 suppressed inhibition of mitochondrial complex activity by MPP+ and actually resulted in a decrease of α-synuclein phosphorylation and aggregation induced by MMP+ treatment in PC12 cells. LIUS stimulation also inhibited expression of casein kinase 2 (CK2) that appears to mediate ROS-dependent α-synuclein aggregation. Finally, LIUS stimulation alleviated the death of PC12 cells by MPP+ treatment in an intensity-dependent manner. We, hence, suggest that LIUS stimulation inhibits ROS generation by MPP+ treatment, thereby suppressing α-synuclein aggregation in PC12 cells.


Subject(s)
1-Methyl-4-phenylpyridinium/pharmacology , Mitochondria/metabolism , Neurons/metabolism , Reactive Oxygen Species/metabolism , Ultrasonic Waves , alpha-Synuclein/metabolism , Animals , Mitochondria/drug effects , Neurons/drug effects , Oxidative Stress/drug effects , PC12 Cells , Rats
7.
J Gerontol A Biol Sci Med Sci ; 68(3): 226-34, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22843669

ABSTRACT

D-chiro-inositol, a member of the inositol family, and pinitol, a 3-methoxy analogue of D-chiro-inositol, have been proposed to have antidiabetic, antiinflammatory, anticancer and stamina enhancing effects. We found that supplementing the diet of Drosophila with D-chiro-inositol and pinitol extended adult longevity in both male and female flies. Life span extension was accompanied by protection against oxidative and starvation stresses, improvement in health span, and no reduction in fecundity. Pinitol increased the fly life span, both in dietary restriction and in ad libitum conditions, suggesting that pinitol increased life span in a manner that was independent of the dietary restriction pathway. Nuclear localization of dFOXO increased in D-chiro-inositol and pinitol-fed flies when compared with controls. Pinitol treatment significantly activated JNK and S6K, but not AKT, indicating that the activation of dFOXO by pinitol is acquired by the activation of S6K and JNK signaling. Hence, our study indicated that D-chiro-inositol and pinitol could be novel food-derived antiaging compounds.


Subject(s)
Drosophila melanogaster/physiology , Inositol/analogs & derivatives , Inositol/pharmacology , Longevity/drug effects , Animals , Drosophila Proteins/metabolism , Female , Fertility/drug effects , Forkhead Transcription Factors/metabolism , Locomotion/drug effects , MAP Kinase Kinase 4/metabolism , Male , Ribosomal Protein S6 Kinases/metabolism , Signal Transduction , Starvation , Stress, Physiological/drug effects
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