• Molecules and Cells
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• 제40권10호
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• pp.752-760
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• 2017

A2B adenosine receptor (A2BAR) is known to be the regulator of bone homeostasis, but its regulatory mechanisms in osteoclast formation are less well-defined. Here, we demonstrate the effect of A2BAR stimulation on osteoclast differentiation and activity by RANKL. A2BAR was expressed in bone marrow-derived monocyte/macrophage (BMM) and RANKL increased A2BAR expression during osteoclastogenesis. A2BAR stimulation with its specific agonist BAY 60-6583 was sufficient to inhibit the activation of ERK1/2, p38 MAP kinases and $NF-{\kappa}B$ by RANKL as well as it abrogated cell-cell fusion in the late stage of osteoclast differentiation. Stimulation of A2BAR suppressed the expression of osteoclast marker genes, such as c-Fos, TRAP, Cathepsin-K and NFATc1, induced by RANKL, and transcriptional activity of NFATc1 was also inhibited by stimulation of A2BAR. A2BAR stimulation caused a notable reduction in the expression of Atp6v0d2 and DC-STAMP related to cell-cell fusion of osteoclasts. Especially, a decrease in bone resorption activity through suppression of actin ring formation by A2BAR stimulation was observed. Taken together, these results suggest that A2BAR stimulation inhibits the activation of ERK1/2, p38 and $NF-{\kappa}B$ by RANKL, which suppresses the induction of osteoclast marker genes, thus contributing to the decrease in osteoclast cell-cell fusion and bone resorption activity.

• 약학회지
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• 제59권5호
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• pp.207-214
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• 2015

P2Y receptors, a type of P2 receptor family, are G-protein coupled receptors and 8 subtypes have been characterized ($P2Y_1$, $P2Y_2$, $P2Y_4$, $P2Y_6$, $P2Y_{11-14}$). Recently, several studies have shed light on the role of P2Y receptors in bone biology. Among them, little is known on the role of $P2Y_6$ receptor on osteoclast differentiation. Thus, we investigated the role of $P2Y_6$ receptor on osteoclastogenesis using $P2Y_6$ receptor selective antagonist, MRS 2578. When osteoblasts and bone marrow cells were co-cultured in the presence of $VitD_3$ and $PGE_2$, $P2Y_6$ antagonist increased the formation of TRAP positive osteoclasts. To elucidate the target cells of $P2Y_6$ antagonist, we first checked the effect of MRS 2578 on osteoblasts. Treatment of MRS 2578 did not affect OPG : RANKL mRNA ratio in osteoblasts. Next, we checked the effects of $P2Y_6$ antagonist on osteoclast precursors using mouse bone marrow macrophages (BMMs). Addition of MRS 2578 increased the number of osteoclasts in RANKL-treated BMMs. Although $P2Y_6$ antagonist had no effect on RANKL-induced NFATc1, c-Fos and MafB expression levels, it significantly stimulated RANKL-induced Blimp1 mRNA expression in BMMs. Taken together, these data indicate that $P2Y_6$ antagonist increases osteoclast formation by upregulation of Blimp1 expression.

• 동의생리병리학회지
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• 제23권6호
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• pp.1299-1304
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• 2009

We have previously shown that water extract of deer antler (WEDA) inhibited RANKL-mediated osteoclast differentiation from bone marrow macrophages by suppressing c-Fos and NFATc1 expression. Thus, we examined the effect of WEDA in inflammation-induced bone loss in vivo. Here we found that WEDA inhibited osteoblast-supported osteoclast differentiation induced by lipopolysaccharide (LPS). However, WEDA did not suppress the expression of receptor activator of NF-${\kappa}B$ ligand (RANKL) in response to LPS in osteoblasts. WEDA also inhibited the bone resorptive activity of mature osteoclasts. To examine the effect of WEDA on bone loss, when LPS injected subcutaneously in mice, bone loss was greatly increased, but WEDA treatment inhibited LPS-mediated bone loss. Taken together, we conclude that WEDA inhibited osteoclast differentiation and bone resorption in vitro and in vivo. Thus WEDA may be useful in the treatment of bone-related disorders.

• 생약학회지
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• 제44권3호
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• pp.257-262
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• 2013

Osteoporosis is a disease of bones that leads to an increased risk of fracture. In osteoporosis, the bone mineral density is reduced, bone microarchitecture deteriorates, and the amount and variety of proteins in bone are altered. $It^{\circ}{\emptyset}s$ caused by the imbalance between born resorption and born formation. Recently natural products from plants have been extensively studied as therapeutic drugs to treat and prevent various diseases. Wheat bran is the hard outer layers of wheat grain and produced as a by-product of milling in the production of refined grains. In oriental medicines, Bu So Maek (Tritici Immaturi Semen) with wheat bran has been used as bronchitis, sedatives and anti-sweating effects. However effects of wheat bran butanol fraction (WBB, 50 ${\mu}g/ml$) in osteoclast differentiation remains unknown yet. Thus we investigated the effects of WBB on RANKL induced osteoclast differentiation. WBB inhibited osteoclast differentiation by downregulating the RANKL-induced activations of MAP kinases. Moreover mRNA expression of osteoclast-mediating molecules such as c-Fos, NFATc1 and DC-STAMP were attenuated by WBB during osteoclast differentiation. The finding of this study show that WBB and its components might prevent osteoclast-related bone loss.

• 동의생리병리학회지
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• 제20권1호
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• pp.65-68
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• 2006

It was examined the effect of fermented rice wine using mycelium of Phellinus linteus (FWPL) on the gastric mucosa of rat. The gastric mucosal lesions were not seen macroscopically in normal, but ethanol-administrated rats produced congestion and edema with a few local lesions. The administration of FWPL showed a similar pattern as like normal except trace histopathological changes. The results of Western blot analyses showed that the higher expression of inducible nitric oxygenase (iNOS), cyclooxygenase (COX)-1, COX-2, tumor necrosis factor-$\alpha$ and c-fos, especially COX-2, in the ethanol-administrated rat compared with normal rat. But FWPL-administrated rat showed a trace increase of these expression compared to normal rat. About immunohistochemical observations, weaker iNOS reactions were detected in mucous cells of epithelim of ethanol administrated rat compared with normal and FWPL-administrated rat. These results suggested that FWPL-administrated rat showed a trace changes on the mucus barrier-related protein expression compared with ethanol-administrated rat and thus FWPL may be use to develop a functional alcoholic beverage.

• Molecules and Cells
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• 제43권1호
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• pp.34-47
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• 2020

The circadian clock regulates various physiological processes, including bone metabolism. The nuclear receptors Reverbs, comprising Rev-erbα and Rev-erbβ, play a key role as transcriptional regulators of the circadian clock. In this study, we demonstrate that Rev-erbs negatively regulate differentiation of osteoclasts and osteoblasts. The knockdown of Rev-erbα in osteoclast precursor cells enhanced receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation, as well as expression of nuclear factor of activated T cells 1 (NFATc1), osteoclast-associated receptor (OSCAR), and tartrate-resistant acid phosphatase (TRAP). The overexpression of Rev-erbα leads to attenuation of the NFATc1 expression via inhibition of recruitment of c-Fos to the NFATc1 promoter. The overexpression of Rev-erbα in osteoblast precursors attenuated the expression of osteoblast marker genes including Runx2, alkaline phosphatase (ALP), bone sialoprotein (BSP), and osteocalcin (OC). Rev-erbα interfered with the recruitment of Runx2 to the promoter region of the target genes. Conversely, knockdown of Rev-erbα in the osteoblast precursors enhanced the osteoblast differentiation and function. In addition, Rev-erbα negatively regulated osteoclast and osteoblast differentiation by suppressing the p38 MAPK pathway. Furthermore, intraperitoneal administration of GSK4112, a Rev-erb agonist, protects RANKL-induced bone loss via inhibition of osteoclast differentiation in vivo. Taken together, our results demonstrate a molecular mechanism of Rev-erbs in the bone remodeling, and provide a molecular basis for a potential therapeutic target for treatment of bone disease characterized by excessive bone resorption.

• Journal of Ginseng Research
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• 제45권6호
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• pp.706-716
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• 2021

Background: Irritable bowel syndrome (IBS), the most common functional gastrointestinal disorder, is characterized by chronic abdominal pain and bowel habit changes. Although diverse complicated etiologies are involved in its pathogenesis, a dysregulated gut-brain axis may be an important factor. Red ginseng (RG), a traditional herbal medicine, is proven to have anti-inflammatory effects and improve brain function; however, these effects have not been investigated in IBS. Methods: Three-day intracolonic zymosan injections were used to induce post-infectious human IBS-like symptoms in mice. The animals were randomized to receive either phosphate-buffered saline (CG) or RG (30/100/300 mg/kg) for 10 days. Amitriptyline and sulfasalazine were used as positive controls. Macroscopic scoring was performed on day 4. Visceral pain and anxiety-like behaviors were assessed by colorectal distension and elevated plus maze and open field tests, respectively, on day 10. Next-generation sequencing of gut microbiota was performed, and biomarkers involved in gut-brain axis responses were analyzed. Results: Compared to CG, RG significantly decreased the macroscopic score, frequency of visceral pain, and anxiety-like behavior in the IBS mice. These effects were comparable to those after sulfasalazine and amitriptyline treatments. Moreover, RG significantly increased the proliferation of beneficial microbes, including Lactobacillus johnsonii, Lactobacillus reuteri, and Parabacteroides goldsteinii. RG significantly suppressed expression of IL-1β and c-fos in the gut and prefrontal cortex, respectively. Further, it restored the plasma levels of corticosterone to within the normal range, accompanied by an increase in adrenocorticotropic hormone. Conclusion: RG may be a potential therapeutic option for the management of human IBS.

• Research in Vestibular Science
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• 제17권4호
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• pp.142-151
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• 2018

Objectives: Excitability o medial vestibular nucleus (MVN) in the brainstem can be affected by changes in the arterial blood pressure. Several animal studies have demonstrated that acute hypotension results in the alteration of multiunit activities and expression of cFos protein in the MVN. In the field of extracellular electrophysiological recording, tetrode technology and spike sorting algorithms can easily identify single unit activity from multiunit activities in the brain. However, detailed properties of electrophysiological changes in single unit of the MVN during acute hypotension have been unknown. Methods: Therefore, we applied tetrode techniques and electrophysiological characterization methods to know the effect of acute hypotension on single unit activities of the MVN of rats. Results: Two or 3 types of unit could be classified according to the morphology of spikes and firing properties of neurons. Acute hypotension elicited 4 types of changes in spontaneous firing of single unit in the MVN. Most of these neurons showed excitatory responses for about within 1 minute after the induction of acute hypotension and then returned to the baseline activity 10 minutes after the injection of sodium nitroprusside. There was also gradual increase in spontaneous firing in some units. In contrast small proportion of units showed rapid reduction of firing rate just after acute hypotension. Conclusions: Therefore, application of tetrode technology and spike sorting algorithms is another method for the monitoring of electrical activity of vestibular nuclear during acute hypotension.

• Korean Journal of Acupuncture
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• 제36권2호
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• pp.93-103
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• 2019

Objectives : The aim of this study is to review the current trends in experimental studies on the acupuncture moxibustion treatment for visceral hypersensitivity. Methods : PubMed was searched for experimental studies about visceral hypersensitivity and acupuncture/moxibustion. Data were extracted and tabulated from the selected articles about experimental method, intervention, result and mechanism. Results : Total 23 articles were reviewed. Chronic visceral hypersensitivity animal model was applied in 17 studies (74%). Visceral hypersensitivity was measured by abdominal withdrawal reflex scoring or/and abdominal electromyogram. Acupoints like ST25, ST36, ST37, BL25, LI11, BL32 and PC6 were treated by electroacupuncture or moxibustion. All articles reported that electroacupuncture or moxibustion treatment is significantly effective in reducing visceral hypersensitivity. Treatment mechanisms were studied, related to mast cell, serotonin (5-HT) and receptor (5-HT3R and 5-HT4R), substance P (SP), vasoactive intestinal polypeptide (VIP), c-fos positive cell, corticotropin-releasing hormone (CRH), purinergic 2X (P2X)2, P2X3, P2X4, P2X7, N-methyl-D-aspartate (NMDA) receptor (NR1 and NR2B), prokinectin (PK) 1 and PK2. Conclusions : Evidences on acupuncture/moxibustion treatment for visceral hypersensitivity in animal studies warrant more research on effective acupoins, electro-acupuncture methods and treatment durations.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 추계학술대회
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• pp.67-67
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• 2019

Vaccinium oldhamii (V. oldhamii) has been reported to exert a variety of the pharmacological properties such as anti-oxidant activity, anti-cancer activity, and inhibitory activity of ${\alpha}$-amylase and acetylcholinesterase. However, the anti-inflammatory activity of V. oldhamii has not been studied. In this study, we aimed to investigate anti-inflammatory activity of the stem extracts from V. oldhamii, and to elucidate the potential mechanisms in LPS-stimulated RAW264.7 cells. Among VOS, VOL and VOF, the inhibitory effect of NO and PGE2 production induced by LPS was highest in VOS treatment. Thus, VOS was selected for the further study. VOS dose-dependently blocked LPS-induced NO and PGE2 production by inhibiting iNOS and COX-2 expression, respectively. VOS inhibited the expression of pro-inflammatory cytokines such as $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. In addition, VOS suppressed TRAP activity and attenuated the expression of the osteoclast-specific genes such as NFATc1, c-FOS, TRAP, MMP-9, cathepsin K, CA2, OSCAR and ATPv06d2. VOS inhibited LPS-induced $NF-{\kappa}B$ signaling activation through blocking $I{\kappa}B-{\alpha}$ degradation and p65 nuclear accumulation. VOS inhibited MAPK signaling activation by attenuating the phosphorylation of ERK1/2, p38 and JNK. Furthermore, VOS inhibited ATF2 phosphorylation and blocked ATF2 nuclear accumulation. From these findings, VOS has potential to be a candidate for the development of chemopreventive or therapeutic agents for the inflammatory diseases.