Activation of transient receptor potential vanilloid 1 (TRPV1), a calcium permeable channel expressed in primary sensory neurons, induces the release of glutamate from their central and peripheral afferents during normal acute and pathological pain. However, little information is available regarding the glutamate release mechanism associated with TRPV1 activation in primary sensory neurons. To address this issue, we investigated the expression of vesicular glutamate transporter (VGLUT) in TRPV1-immunopositive (+) neurons in the rat trigeminal ganglion (TG) under normal and complete Freund’s adjuvant (CFA)-induced inflammatory pain conditions using behavioral testing as well as double immunofluorescence staining with antisera against TRPV1 and VGLUT1 or VGLUT2. TRPV1 was primarily expressed in small and medium-sized TG neurons. TRPV1+ neurons constituted approximately 27% of all TG neurons. Among all TRPV1+ neurons, the proportion of TRPV1+ neurons coexpressing VGLUT1 (VGLUT1+/ TRPV1+ neurons) and VGLUT2 (VGLUT2+/TRPV1+ neurons) was 0.4% ± 0.2% and 22.4% ± 2.8%, respectively. The proportion of TRPV1+ and VGLUT2+ neurons was higher in the CFA group than in the control group (TRPV1+ neurons: 31.5% ± 2.5% vs. 26.5% ± 1.2%, VGLUT2+ neurons: 31.8% ± 1.1% vs. 24.6% ± 1.5%, p < 0.05), whereas the proportion of VGLUT1+, VGLUT1+/TRPV1+, and VGLUT2+/TRPV1+ neurons did not differ significantly between the CFA and control groups. These findings together suggest that VGLUT2, a major isoform of VGLUTs, is involved in TRPV1 activation-associated glutamate release during normal acute and inflammatory pain.

신경내분비종양은 소마토스타틴 수용체의 발현이 증가되어 있다. 소마토스타틴 수용체를 표적으로 하는 소마토스타틴 유사체 옥트레오티드는 오랫동안 신경내분비종양의 기능을 억제하는 치료제로 사용되어 왔다. 옥트레오티드에 핵의학 영상용 방사성동위원소 In-111을 표지하여 환자에 주사한 후 감마카메라로 전신을 촬영하는 기능적 핵의학 영상 또한 오래전부터 사용되었다. 최근에는 옥트레오티드 유사체에 양전자단층촬영(positron emission tomography, PET)용 방사성동위원소를 표지하여 PET/CT를 촬영하게 되었는데 기존 In-111 옥트레오스캔보다 더 선명한 영상을 얻을 수 있다. 나아가 옥트레오티드 유사체에 치료용 방사성핵종을 표지하여 주사하면 신경내분비종양의 전이된 병소를 찾아가서 방사선 치료를 하는 일명 방사선 미사일 치료가 개발되었다. 이는 펩타이드 수용체를 표적으로 하는 핵의학 치료의 일종으로 펩타이드 수용체 방사성핵종 치료(peptide receptor radionuclide therapy, PRRT)라고 한다. 같은 소마토스타틴 수용체 표적 펩타이드를 이용하여 치료 전 기능 영상을 얻어서 PRRT의 대상 환자를 선별할 수 있어 환자 개인맞춤 정밀치료가 가능하다. 또한 Lu-177과 같은 영상용 감마선과 치료용 베타선을 동시에 방출하는 방사성동위원소를 표지하면 치료와 동시에 감마카메라 영상을 얻을 수 있어 주사한 표적치료제의 분포를 매 치료마다 평가할 수 있어 진단과 치료의 합성어인 테라노스틱스가 가능하다.

Dopamine (DA) receptor (D1 and D2-like receptors) agonists are known to affect expression levels of DA receptors. Rotigotine, a DA D2-like receptor agonist, has been developed for treating Parkinson’s disease (PD). However, its role in PD by acting through DA D2-like receptors has not been fully understood yet. The purpose of this study was to investigate neuroprotective effects of rotigotine through DA D2 and D3 receptors in 6-hydroxydopamine (6-OHDA) induced mouse model of PD. Expression level of tyrosine hydroxylase (TH) was examined using immunohistochemistry and Western blot analysis. Results revealed that unilateral injection of 6-OHDA into the midbrain caused significant loss of TH positive cells in the substantia nigra, whereas rotigotine inhibited such loss of TH cells in 6-OHDA-induced mouse model of PD. In vitro experiments demonstrated that rotigotine increased expression levels of TH against 6-OHDA-induced toxicity. The expression level of TH after treatment with L’741,626, a D2 receptor antagonist was decreased more than that after treatment with GR 103691, a D3 receptor antagonist. These results suggest that rotigotine can protect DA neurons against 6-OHDA induced toxicity and that the protective effect of rotigotine for DAergic neurons through a DA D2 receptor is stronger than that through a DA D3 receptor.

Equine follicle stimulating hormone receptor (eFSHR) has a large extracellular domain and an intracellular domain containing approximately 10 phosphorylation sites within the G protein-coupled receptor. This study was conducted to analyze the function of phosphorylation sties at the eFSHR C-terminal region. We constructed a mutant of eFSHR, in which the C-terminal cytoplasmic tail was truncated at residue 641 (eFSHR-t641). This removed 10 potential phosphorylation sites from the C-terminal region of the intracellular loop. The eFSHR-wild type (eFSHR-wt) and eFSHR-t641 cDNAs were subcloned into the pCMV-ARMS1-PK2 expression vector. These plasmids were transfected into PathHunter CHO-K1 Parental cells expressing β-arrestin 2 enzyme acceptor fusion protein and analyzed for agonist-induced cAMP response. The cAMP response in cells expressing eFSHR-t641 was lower than the response in cells expressing eFSHR-wt. EC50 values of eFSHR-wt and eFSHR-t641 were 1079 ng/mL and 1834 ng/mL, respectively. eFSHR-t641 was approximately 0.58-fold compared with that of eFSHR-wt. The maximal response in eFSHR-wt and eFSHR-t641 was 24.7 nM and 16.7 nM, respectively. The Rmax value of phosphorylation sites in eFSHR-t641 was also decreased to approximately 68.4% of that in eFSHR-wt. The collective data implicate that the phosphorylation sites in the eFSHR C-terminal region have a pivotal role in signal transduction in PathHunter CHO-K1 cells, and indicate that β-arrestin is involved in coupling the activated receptors to the internalization system.

Carcass grade primarily depends on marbling of intramuscular fat, which is associated with the texture and tenderness of beef. Accordingly, various economical molecular tests for high intramuscular fat in beef have been attempted. Especially, Hanwoo (Korean Cattle) intramuscular fat has higher levels of monounsaturated fatty acids than that in the beef of other cattle. Intramuscular fats are associated with levels of lipid metabolic genes in the liver transcriptome. Therefore, hepatic triglyceride synthesis can considerably increase intramuscular fat. To investigate the relationship between hepatic lipogenesis and carcass grade, we analyzed 52 Hanwoo liver samples from domestic farms, and evaluated lipid levels and transcript levels of glucose and lipid metabolism-related genes according to carcass grade. Oil-Red-O staining revealed fatty livers in high carcass grades. Moreover, we found significantly higher levels of mRNA for lipogenesis, glycolysis, and triglyceride synthesis genes in high carcass grade livers. Importantly, progesterone receptor membrane component 1 (Pgrmc1) levels were significantly lower in high carcass grade livers. As Pgrmc1 suppression is correlated with induction of de novo lipogenesis (DNL) and glycolysis genes, it has a diagnostic impact for high carcass grades. These results could be used for genetic improvements in carcass grades of cattle. More importantly, as Pgrmc1 can be detected in blood peripheral nucleated cells, it also has value for rapid blood diagnosis.

Lysophosphatidic acid (LPA) is a lipid messenger mediated by G protein-coupled receptors (LPAR1-6). It is involved in the pathogenesis of certain chronic inflammatory and autoimmune diseases. In addition, it controls the self-renewal and differentiation of stem cells. Recent research has demonstrated the close relationship between periodontitis and various diseases in the human body. However, the precise role of LPA in the development of periodontitis has not been studied. We identified that LPAR1 was highly expressed in human periodontal ligament stem cells (PDLSCs). In periodontitis-mimicking conditions with Porphyromonas gingivalis -derived lipopolysaccharide (Pg-LPS) treatment, PDLSCs exhibited a considerable reduction in the cellular viability and osteogenic differentiation potential, in addition to an increase in the inflammatory responses including tumor necrosis factor-α and interleukin-1β expression and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation. Of the various LPAR antagonists, pre-treatment with AM095, an LPAR1 inhibitor, showed a positive effect on the restoration of cellular viability and osteogenic differentiation, accompanied by a decrease in NF-κB signaling, and action against Pg-LPS. These findings suggest that the modulation of LPAR1 activity will assist in checking the progression of periodontitis and in its treatment.

The fruit of Chaenomeles sinensis (Thouin) Koehne (Chaenomelis Fructus) known as “Mo-Gua” in Korea has been commonly used in traditional medicine to treat inflammatory diseases, such as sore throat. However, its effect on bone metabolism has not been elucidated yet. Here, we examined the effect of Chaenomelis Fructus ethanol extract (CFE) on receptor activator of nuclear factor (NF)-κB ligand (RANKL)-mediated osteoclast differentiation and formation. CF-E considerably inhibited osteoclast differentiation and tartrate-resistant acid phosphatase-positive multinuclear cell formation from bone marrow-derived macrophages and osteoclast precursor cells in a dose-dependent manner. In addition, the formation of actin rings and resorption pits were significantly suppressed in CF-E-treated osteoclasts as compared with the findings in non-treated control cells. Consistent with these phenotypic inhibitory results, the expressions of osteoclast differentiation marker genes (Acp5, Atp6v0d2 , Oscar, CtsK, and Tm7sf4) and Nfatc1 , a pivotal transcription factor for osteoclastogenesis, were markedly decreased by CF-E treatment. The inhibitory effect of CF-E on RANKL-induced osteoclastogenesis was associated with the suppression of NFATc1 expression, not by regulation of mitogen-activated protein kinases and NF-κB activation but by the inactivation of phospholipase C gamma 1 and 2. These results indicate that CF-E has an inhibitory effect on osteoclast differentiation and formation, and they suggest the possibility of CF-E as a traditional therapeutic agent against bone-resorptive diseases, such as osteoporosis, rheumatoid arthritis, and periodontitis.

This study aimed to investigate the function of the constitutively activating mutation D540G on eel FSHR activity by in vitro functional studies. Site-directed mutagenesis was carried out to generate the D-to-G mutation at position 540 of the pcDNA3-eel FSHR construct. Vectors expressing either wild type or mutant receptor were transfected into Chinese hamster ovary (CHO-K1) cells. The functional characteristics of both the wild type and mutant receptors were analyzed by a cAMP assay. cAMP accumulation was highly increased in cells transfected with the D540G mutant receptor in a dose-dependent manner. Of note, basal cAMP levels were remarkably increased (~13.1-fold) with expression of this mutant when compared to wild type receptor. These findings suggest that the D540G mutation in the eel FSHR may contribute to ovulation during eel sex maturation as well as play a pivotal role in inducing FSHR activity.

본 연구에서는 CMB(Chemical Mass Balance) 모델을 이용하여 PM2.5에 대한 오염원 확인 및 오염원별 기여도를 분석하였다. A시의 배출원별 기여도 순위는 비산먼지(30.1%) > 생물성 연소(21.9%) > 2차 오염물질(21.1%) > 도로이동오염원(19.3%) > 면오염원(7.6%) 순이고, CMB 모델 기여도와 CAPSS(Clean Air Policy Support System) 배출자료 기여도 비교에서 증가한 배출원은 생물성 연소와 2차 오염물질이고, 감소한 배출원은 도로이동오염원, 비산먼지, 면오염원으로 분석되었다.

Xylitol is well-known to have an anti-caries effect by inhibiting the replication of cariogenic bacteria. In addition, xylitol enhances saliva secretion. However, the precise molecular mechanism of xylitol on saliva secretion is yet to be elucidated. Thus, in this study, we aimed to investigate the stimulatory effect of xylitol on saliva secretion and to further evaluate the involvement of xylitol in muscarinic type 3 receptor (M3R) signaling. For determining these effects, we measured the saliva flow rate following xylitol treatment in healthy individuals and patients with dry mouth. We further tested the effects of xylitol on M3R signaling in human salivary gland (HSG) cells using realtime quantitative reverse-transcriptase polymerase chain reaction, immunoblotting, and immunostaining. Xylitol candy significantly increased the salivary flow rate and intracellular calcium release in HSG cells via the M3R signaling pathway. In addition, the expressions of M3R and aquaporin 5 were induced by xylitol treatment. Lastly, we investigated the distribution of M3R and aquaporin 5 in HSG cells. Xylitol was found to activate M3R, thereby inducing increases in Ca2+ concentration. Stimulation of the muscarinic receptor induced by xylitol activated the internalization of M3R and subsequent trafficking of aquaporin 5. Taken together, these findings suggest a molecular mechanism for secretory effects of xylitol on salivary epithelial cells.

Melatonin is a neurotransmitter that modulates various physiological phenomena including regulation and maintenance of the circadian rhythm. Nicotinic acetylcholine receptors (nAChRs) play an important role in oral functions including orofacial muscle contraction, salivary secretion, and tooth development. However, knowledge regarding physiological crosstalk between melatonin and nAChRs is limited. In the present study, the melatoninmediated modulation of nAChR functions using bovine adrenal chromaffin cells, a representative model for the study of nAChRs, was investigated. Melatonin inhibited the nicotinic agonist dimethylphenylpiperazinium (DMPP) iodide-induced cytosolic free Ca2+ concentration ([Ca2+]i) increase and norepinephrine secretion in a concentrationdependent manner. The inhibitory effect of melatonin on the DMPP-induced [Ca2+]i increase was observed when the melatonin treatment was performed simultaneously with DMPP. The results indicate that melatonin inhibits nAChR functions in both peripheral and central nervous systems.