Potential Rheumatoid Arthritis-Associated Interstitial Lung Disease Treatment and Computational Approach for Future Drug Development.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by swelling in at least one joint. Owing to an overactive immune response, extra-articular manifestations are observed in certain cases, with interstitial lung disease (ILD) being the most common. Rheumatoid arthritis-associated interstitial lung disease (RA-ILD) is characterized by chronic inflammation of the interstitial space, which causes fibrosis and the scarring of lung tissue. Controlling inflammation and pulmonary fibrosis in RA-ILD is important because they are associated with high morbidity and mortality. Pirfenidone and nintedanib are specific drugs against idiopathic pulmonary fibrosis and showed efficacy against RA-ILD in several clinical trials. Immunosuppressants and disease-modifying antirheumatic drugs (DMARDs) with anti-fibrotic effects have also been used to treat RA-ILD. Immunosuppressants moderate the overexpression of cytokines and immune cells to reduce pulmonary damage and slow the progression of fibrosis. DMARDs with mild anti-fibrotic effects target specific fibrotic pathways to regulate fibrogenic cellular activity, extracellular matrix homeostasis, and oxidative stress levels. Therefore, specific medications are required to effectively treat RA-ILD. In this review, the commonly used RA-ILD treatments are discussed based on their molecular mechanisms and clinical trial results. In addition, a computational approach is proposed to develop specific drugs for RA-ILD.

Vitamin D3 Exerts Beneficial Effects on C2C12 Myotubes through Activation of the Vitamin D Receptor (VDR)/Sirtuins (SIRT)1/3 Axis.

The onset of sarcopenia is associated with a decline in vitamin D receptor (VDR) expression, wherein reduced VDR levels contribute to muscle atrophy, while heightened expression promotes muscle hypertrophy. Like VDR, the age-related decline in protein deacetylase sirtuin (SIRT) expression is linked to the development of sarcopenia and age-related muscle dysfunction. This study aimed to investigate whether the VDR agonist 1,25-dihydroxyvitamin D3 (1,25VD3) exerts beneficial effects on muscles through interactions with sirtuins and, if so, the underlying molecular mechanisms. Treatment of 1,25VD3 in differentiating C2C12 myotubes substantially elevated VDR, SIRT1, and SIRT3 expression, enhancing their differentiation. Furthermore, 1,25VD3 significantly enhanced the expression of key myogenic markers, including myosin heavy chain (MyHC) proteins, MyoD, and MyoG, and increased the phosphorylation of AMPK and AKT. Conversely, VDR knockdown resulted in myotube atrophy and reduced SIRT1 and SIRT3 levels. In a muscle-wasting model triggered by IFN-γ/TNF-α in C2C12 myotubes, diminished VDR, SIRT1, and SIRT3 levels led to skeletal muscle atrophy and apoptosis. 1,25VD3 downregulated the increased expression of muscle atrophy-associated proteins, including FoxO3a, MAFbx, and MuRF1 in an IFN-γ/TNF-α induced atrophy model. Importantly, IFN-γ/TNF-α significantly reduced the mtDNA copy number in the C2C12 myotube, whereas the presence of 1,25VD3 effectively prevented this decrease. These results support that 1,25VD3 could serve as a potential preventive or therapeutic agent against age-related muscle atrophy by enhancing the VDR/SIRT1/SIRT3 axis.

Etiology and Pathogenesis of Rheumatoid Arthritis-Interstitial Lung Disease.

Interstitial lung disease (ILD) is one of the most serious extra-articular complications of rheumatoid arthritis (RA), which increases the mortality of RA. Because the pathogenesis of RA-ILD remains poorly understood, appropriate therapeutic strategies and biomarkers have not yet been identified. Thus, the goal of this review was to summarize and analyze the reported data on the etiology and pathogenesis of RA-ILD. The incidence of RA-ILD increases with age, and is also generally higher in men than in women and in patients with specific genetic variations and ethnicity. Lifestyle factors associated with an increased risk of RA-ILD include smoking and exposure to pollutants. The presence of an anti-cyclic citrullinated peptide antibody, high RA disease activity, and rheumatoid factor positivity also increase the risk of RA-ILD. We also explored the roles of biological processes (e.g., fibroblast-myofibroblast transition, epithelial-mesenchymal transition, and immunological processes), signaling pathways (e.g., JAK/STAT and PI3K/Akt), and the histopathology of RA involved in RA-ILD pathogenesis based on published preclinical and clinical models of RA-ILD in animal and human studies.

Effects of aging-induced obesity on the transcriptional expression of adipogenesis and thermogenic activity in the gonadal white adipose, brown adipose, and skeletal muscle tissues.

PURPOSE: Aging is closely associated with chronic metabolic diseases, such as obesity, which lead to increased adiposity, skeletal muscle wasting, and imbalanced cellular energy metabolism. However, transcriptional profiles representing energy imbalances in aging-induced obesity are not fully understood. Thus, this study aimed to investigate the candidate genes predominantly regulated in aging-related obesity in spontaneously aged mice. METHODS: Male C57BL/6J mice were divided into three age groups according to age: 2- (young), 12- (middle-aged), and 24- (old) months. Body weight and body composition parameters were measured in all mice. Gonadal white adipose tissue (gWAT), brown adipose tissue (BAT), and skeletal muscle (SM) were dissected and weighed. The target tissues were assessed using biochemical and histological assays. RESULTS: Aging-induced obesity increased adipose mass and decreased SM weight through processes of adipocyte hypertrophy; however, recruitment of modulating adipogenesis-inducing transcription factors did not occur. Among adipokines, leptin level was greatly increased in the gWAT during aging. Interestingly, the ß2-adrenergic receptor had a higher affinity than the ß3-adrenergic receptor in aging-induced obesity. For the thermogenic regulation through ß-adrenergic receptors (ß-ARs), a declined uncoupling protein-1 (UCP-1) in the BAT was relevant to aging-induced obesity. CONCLUSION: Aging-induced obesity increases leptin levels in adipocytes and decreases UCP-1 in BAT through ß-ARs, according to transcriptional gene profiling. WAT browning increases energy expenditure due to exercise training adaptations. Further research is needed to discover more effective methods, such as exercise, against aging-induced obesity.

Combinations of Sarcopenia Diagnostic Criteria by Asian Working Group of Sarcopenia (AWGS) 2019 Guideline and Incident Adverse Health Outcomes in Community-Dwelling Older Adults.

OBJECTIVES: This study aimed to investigate the association between combinations of sarcopenia criteria by the Asian Working Group of Sarcopenia (AWGS) 2019 guideline and incident adverse health outcomes. DESIGN: Longitudinal analyses of a cohort study. SETTING AND PARTICIPANTS: We conducted prospective 2-year follow-up analyses (N = 1959) among community-dwelling older adults enrolled in the nationwide Korean Frailty and Aging Cohort Study (KFACS). METHODS: From the KFACS, 1959 older adults (52.8% women; mean age = 75.9 ± 3.9 years) who underwent assessments for appendicular skeletal mass using dual-energy X-ray absorptiometry, handgrip strength, usual gait speed, 5-times sit-to-stand test, and Short Physical Performance Battery (SPPB) at baseline were included. Participants with each adverse health outcome [mobility disability, falls, and instrumental activities of daily living (IADL) disabilities] at baseline were excluded for each corresponding analysis. Multivariable logistic regression was performed to examine whether sarcopenia defined by different diagnostic criteria was associated with incident adverse health outcomes after 2 years. RESULTS: A total of 444 participants (22.7%) were diagnosed with sarcopenia as defined by AWGS 2019. In the multivariable analysis, sarcopenia defined as both low muscle mass and low physical performance increased the risk of mobility disability (OR 2.14, 95% CI 1.35-3.38) and falls (1.74, 95% CI 1.21-2.49). Only the criterion defined as both low muscle mass and physical performance using the SPPB increased the risk of falls with fracture (2.53, 95% CI 1.01-6.35) and IADL disabilities (2.77, 95% CI 1.21-6.33). However, sarcopenia defined as both low muscle mass and low hand grip strength showed no associations with the incidence of any of the adverse health outcomes. CONCLUSIONS AND IMPLICATIONS: Our study suggests that the predictive value of adverse health outcomes for community-dwelling older adults is better when diagnosed with sarcopenia based on low muscle mass and physical performance. Furthermore, using the SPPB as a diagnostic tool for low physical performance may improve the predictive validity for falls with fracture and IADL disability. Our findings may be helpful for the early detection of individuals with sarcopenia who have a higher risk of adverse health outcomes.

Increase in eosinophil-derived neurotoxin level in school children with allergic disease.

Background: Eosinophils are major effector cells of allergic disease and excellent markers of eosinophilic inflammation. Accurate and reliable biomarkers are helpful in the diagnosis, treatment, and control of allergic disease. Objective: This study aimed to investigate an alternate marker of eosinophilic inflammation, eosinophil-derived neurotoxin (EDN), in a number of allergic diseases. Methods: Three hundred ninety-six elementary school-age children with various allergic conditions were recruited for this study. Subgroups included food allergies (FAs), atopic dermatitis (AD), bronchial asthma (BA), and allergic rhinitis (AR). EDN levels in these groups were compared to those in 93 healthy controls (HC). Results: All subjects with allergic disease had elevated levels of serum EDN (median [interquartile range]: FA, 124.2 ng/mL [59.13-160.5 ng/mL]; AD, 110.8 ng/mL [57.52-167.9 ng/mL]; BA, 131.5 ng/mL [60.60-171.0 ng/mL]; AR, 91.32 ng/mL [46.16-145.0 ng/mL]) compared to HC (38.38 ng/mL [32.40-55.62 ng/mL]) (p < 0.0001). These elevated levels were consistent throughout the age range (6-12 years) of the healthy study subjects (p = 0.0679). EDN levels also correlated well with total immunoglobulin E (Rs = 0.5599, p < 0.0001). Looking at all individuals with an allergic disease, the area under the curve was 0.790. Conclusions: Direct measures of eosinophilic inflammation are needed for accurate diagnosis, treatment, and monitoring of allergic diseases. EDN may be a worthy biomarker of eosinophil activity and a useful screening tool for allergic diseases including FA, AD, BA, and AR.

Chair stand test as a proxy for physical performance and muscle strength in sarcopenia diagnosis: the Korean frailty and aging cohort study.

BACKGROUND: The 5-times chair stand test (5CST) is a proxy tool for measuring physical performance and muscle strength in diagnosing sarcopenia. The Asian Working Group for Sarcopenia 2019 guidelines recommends the 5CST for evaluating gait speed, whereas the European Working Group on Sarcopenia in Older People guidelines recommend the chair stand test as a proxy for muscle strength. AIMS: This study sought to determine whether the chair stand test correlates with handgrip strength and gait speed, and investigate sex differences in these relationships. METHODS: We used data collected from 1416 participants (678 men and 738 women) in the 2017 Korean Frailty and Aging Cohort Study (KFACS). RESULTS: The 5CST time had a higher correlation with gait speed (r = - 0.470) than handgrip strength (r = - 0.309). In addition, 5CST time predicted low gait speed (area under the curve [AUC] 0.727) better than low handgrip strength (AUC 0.641). The optimal cutoff values of the 5CST to estimate low gait speed were 10 s for men (sensitivity 62%, specificity 64%) and 11 s for women (sensitivity 68%, specificity 67%). The optimal cutoff values of the 5CST for low handgrip strength were the same as those for low gait speed (10 s for men and 11 s for women). CONCLUSIONS: The 5-times chair stand test fits with gait speed and handgrip strength but seems to be a better proxy of gait speed than handgrip strength. The optimal cutoff values of the 5CST to estimate low gait speed and low handgrip strength were lower in men than women. Although none of the AWGS 2019 or EWGSOP guidelines present sex-specific cutoffs for the 5CST, it needs to be considered in the next guidelines.

Taurine Supplementation Inhibits the Expression of Atrogin-1 and MURF-1, Protein Degradation Marker Genes, in Skeletal Muscle of C26-Induced Cachexia Mouse Model.

This study was designed to investigate the therapeutic effects of taurine in attenuating muscle atrophy. C26 carcinoma cells were cultured and injected into the scapulae of Balb/c mice with 1 × 106 cells. Taurine (200 µl suspension) was orally administered at the concentration of 200 mg/kg of body weight for 2 weeks. Femur muscle tissue, spleen, and gonadal fat tissue were collected and weighed. Muscle tissue was stained by H&E for histopathological analysis. The transcriptional expression of atrogin-1 and MuRF-1 gene was checked by real-time PCR. C26 cells, which induced tumor growth, caused a loss in muscle mass and gonadal fat tissue mass. Simultaneously, there was an increase in spleen and tumor tissue mass. In contrast, taurine supplementation showed a downregulatory effect on the transcriptional expression profile of muscle degradative factors atrogin-1 and MuRF-1. Our findings suggest that taurine has the potential to inhibit muscle atrophy and can be developed as a safe treatment option against muscle loss in sarcopenia patients.

Understanding Viral Infection Mechanisms and Patient Symptoms for the Development of COVID-19 Therapeutics.

Coronavirus disease 2019 (COVID-19), caused by the SARS-CoV-2 virus, has become a worldwide pandemic. Symptoms range from mild fever to cough, fatigue, severe pneumonia, acute respiratory distress syndrome (ARDS), and organ failure, with a mortality rate of 2.2%. However, there are no licensed drugs or definitive treatment strategies for patients with severe COVID-19. Only antiviral or anti-inflammatory drugs are used as symptomatic treatments based on clinician experience. Basic medical researchers are also trying to develop COVID-19 therapeutics. However, there is limited systematic information about the pathogenesis of COVID-19 symptoms that cause tissue damage or death and the mechanisms by which the virus infects and replicates in cells. Here, we introduce recent knowledge of time course changes in viral titers, delayed virus clearance, and persistent systemic inflammation in patients with severe COVID-19. Based on the concept of drug reposition, we review which antiviral or anti-inflammatory drugs can effectively treat COVID-19 patients based on progressive symptoms and the mechanisms inhibiting virus infection and replication.

Dysregulated Autophagy Mediates Sarcopenic Obesity and Its Complications via AMPK and PGC1α Signaling Pathways: Potential Involvement of Gut Dysbiosis as a Pathological Link.

Sarcopenic obesity (SOB), which is closely related to being elderly as a feature of aging, is recently gaining attention because it is associated with many other age-related diseases that present as altered intercellular communication, dysregulated nutrient sensing, and mitochondrial dysfunction. Along with insulin resistance and inflammation as the core pathogenesis of SOB, autophagy has recently gained attention as a significant mechanism of muscle aging in SOB. Known as important cellular metabolic regulators, the AMP-activated protein kinase (AMPK) and the peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α) signaling pathways play an important role in autophagy, inflammation, and insulin resistance, as well as mutual communication between skeletal muscle, adipose tissue, and the liver. Furthermore, AMPK and PGC-1α signaling pathways are implicated in the gut microbiome-muscle axis. In this review, we describe the pathological link between SOB and its associated complications such as metabolic, cardiovascular, and liver disease, falls and fractures, osteoarthritis, pulmonary disease, and mental health via dysregulated autophagy controlled by AMPK and/or PGC-1α signaling pathways. Here, we propose potential treatments for SOB by modulating autophagy activity and gut dysbiosis based on plausible pathological links.

Expression dynamics of integrin α2, α3, and αV upon osteogenic differentiation of human mesenchymal stem cells.

BACKGROUND: The differentiation of human mesenchymal stem cells (hMSCs) into osteoblasts (OBs) is a prerequisite for bone formation. However, little is known about the definitive surface markers for OBs during osteogenesis. METHODS: To study the surface markers on OBs, we generated and used monoclonal antibodies (MAbs) against surface molecules on transforming growth factor-ß1 (TGF-ß1)-treated cancer cells. The generated MAbs were further selected toward expression changes on hMSCs cultured with TGF-ß1/bone morphogenetic protein-2 (BMP-2) or osteogenic differentiation medium (ODM) by flow cytometry. Immunoprecipitation and mass spectrometry were performed to identify target antigens of selected MAbs. Expression changes of the target antigens were evaluated in hMSCs, human periodontal ligament cells (hPDLCs), and human dental pulp cells (hDPCs) during osteogenic and adipogenic differentiation by quantitative polymerase chain reaction (qPCR) and flow cytometry. hMSCs were also sorted by the MAbs using magnetic-activated cell sorting system, and osteogenic potential of sorted cells was evaluated via Alizarin Red S (ARS) staining and qPCR. RESULTS: The binding reactivity of MR14-E5, one of the MAbs, was downregulated in hMSCs with ODM while the binding reactivity of ER7-A7, ER7-A8, and MR1-B1 MAbs was upregulated. Mass spectrometry and overexpression identified that MR14-E5, ER7-A7/ER7-A8, and MR1-B1 recognized integrin α2, α3, and αV, respectively. Upon osteogenic differentiation of hMSCs, the expression of integrin α2 was drastically downregulated, but the expression of integrin α3 and αV was upregulated in accordance with upregulation of osteogenic markers. Expression of integrin α3 and αV was also upregulated in hPDLCs and hDPCs during osteogenic differentiation. Cell sorting showed that integrin αV-high hMSCs have a greater osteogenic potential than integrin αV-low hMSCs upon the osteogenic differentiation of hMSCs. Cell sorting further revealed that the surface expression of integrin αV is more dramatically induced even in integrin αV-low hMSCs. CONCLUSION: These findings suggest that integrin α3 and αV induction is a good indicator of OB differentiation. These findings also shed insight into the expression dynamics of integrins upon osteogenic differentiation of hMSCs and provide the reason why different integrin ligands are required for OB differentiation of hMSCs.

Neuroprotective and Anti-Inflammatory Effects of Low-Moderate Dose Ionizing Radiation in Models of Alzheimer's Disease.

Alzheimer's disease (AD) is the most common cause of dementia. The neuropathological features of AD include amyloid-ß (Aß) deposition and hyperphosphorylated tau accumulation. Although several clinical trials have been conducted to identify a cure for AD, no effective drug or treatment has been identified thus far. Recently, the potential use of non-pharmacological interventions to prevent or treat AD has gained attention. Low-dose ionizing radiation (LDIR) is a non-pharmacological intervention which is currently being evaluated in clinical trials for AD patients. However, the mechanisms underlying the therapeutic effects of LDIR therapy have not yet been established. In this study, we examined the effect of LDIR on Aß accumulation and Aß-mediated pathology. To investigate the short-term effects of low-moderate dose ionizing radiation (LMDIR), a total of 9 Gy (1.8 Gy per fraction for five times) were radiated to 4-month-old 5XFAD mice, an Aß-overexpressing transgenic mouse model of AD, and then sacrificed at 4 days after last exposure to LMDIR. Comparing sham-exposed and LMDIR-exposed 5XFAD mice indicated that short-term exposure to LMDIR did not affect Aß accumulation in the brain, but significantly ameliorated synaptic degeneration, neuronal loss, and neuroinflammation in the hippocampal formation and cerebral cortex. In addition, a direct neuroprotective effect was confirmed in SH-SY5Y neuronal cells treated with Aß1-42 (2 µM) after single irradiation (1 Gy). In BV-2 microglial cells exposed to Aß and/or LMDIR, LMDIR therapy significantly inhibited the production of pro-inflammatory molecules and activation of the nuclear factor-kappa B (NF-κB) pathway. These results indicate that LMDIR directly ameliorated neurodegeneration and neuroinflammation in vivo and in vitro. Collectively, our findings suggest that the therapeutic benefits of LMDIR in AD may be mediated by its neuroprotective and anti-inflammatory effects.

Taurine Stimulates Thermoregulatory Genes in Brown Fat Tissue and Muscle without an Influence on Inguinal White Fat Tissue in a High-Fat Diet-Induced Obese Mouse Model.

This study was conducted to investigate if taurine supplementation stimulates the induction of thermogenic genes in fat tissues and muscles and decipher the mechanism by which taurine exerts its anti-obesity effect in a mildly obese ICR (CD-1®) mouse model. Three groups of ICR mice were fed a normal chow diet, a high-fat diet (HFD), or HFD supplemented with 2% taurine in drinking water for 28 weeks. The expression profiles of various genes were analyzed by real time PCR in interscapular brown adipose tissue (BAT), inguinal white adipose tissue (iWAT), and the quadriceps muscles of the experimental groups. Genes that are known to regulate thermogenesis like PGC-1α, UCP-1, Cox7a1, Cox8b, CIDE-A, and ß1-, ß2-, and ß3-adrenergic receptors (ß-ARs) were found to be differentially expressed in the three tissues. These genes were expressed at a very low level in iWAT as compared to BAT and muscle. Whereas, HFD increased the expression of these genes. Taurine supplementation stimulated the expression of UCP-1, Cox7a1, and Cox8b in BAT and only Cox7a1 in muscle, while there was a decrease in iWAT. In contrast, fat deposition-related genes, monoamine oxidases (MAO)-A, and -B, and lipin-1, were decreased by taurine supplementation only in iWAT and not in BAT or muscle. In conclusion, the potential anti-obesity effects of taurine may be partly due to upregulated thermogenesis in BAT, energy metabolism of muscle, and downregulated fat deposition in iWAT.

Analysis of Sasang Constitutional Medicine as an Optimal Preventive Care Strategy for Hemophilia Patients.

Introduction. Medical improvements have allowed hemophilia patients to anticipate an increased quality of life and life expectancy similar to that of the general population. Analysis of the potential disease symptoms of hemophilia patients based on a survey of Sasang Constitutional Medicine (SCM) is important for optimal preventive care and adjunctive therapy to avoid life-threating complications. AIM: To predict potential disease symptoms from the viewpoint of SCM as a preventive care strategy for hemophilia patients. METHODS: Sixty-one hemophilia patients responded to a survey on Sasang constitutional classification, hemophilia disease pattern, and original symptoms. RESULTS: In terms of SCM type, the 61 of hemophilia patients included 37 Tae-Eum (60.7%), 18 So-Yang (29.5%), and 6 So-Eum (12.5%). Hemophilia was found to be higher in Tae-Eum type and lower in So-Yang and So-Eum types, while considering the distributional rate of Korean Sasang types. Most of the patients with Tae-Eum type had Joyeol or Ganyeol. Furthermore, the incidences of diabetes and high blood pressure were greater in Tae-Eum type than in those of other types. CONCLUSION: In order to increase the quality of life and overall life expectancy, hemophilia patients with Tae-Eum type should be treated through management according to SCM along with medicine against hemophilia as long-term preventive care. Diabetes and high blood pressure should be regularly monitored in patients with Tae-Eum type.

Multifaceted Physiological Roles of Adiponectin in Inflammation and Diseases.

Adiponectin is the richest adipokine in human plasma, and it is mainly secreted from white adipose tissue. Adiponectin circulates in blood as high-molecular, middle-molecular, and low-molecular weight isoforms. Numerous studies have demonstrated its insulin-sensitizing, anti-atherogenic, and anti-inflammatory effects. Additionally, decreased serum levels of adiponectin is associated with chronic inflammation of metabolic disorders including Type 2 diabetes, obesity, and atherosclerosis. However, recent studies showed that adiponectin could have pro-inflammatory roles in patients with autoimmune diseases. In particular, its high serum level was positively associated with inflammation severity and pathological progression in rheumatoid arthritis, chronic kidney disease, and inflammatory bowel disease. Thus, adiponectin seems to have both pro-inflammatory and anti-inflammatory effects. This indirectly indicates that adiponectin has different physiological roles according to an isoform and effector tissue. Knowledge on the specific functions of isoforms would help develop potential anti-inflammatory therapeutics to target specific adiponectin isoforms against metabolic disorders and autoimmune diseases. This review summarizes the current roles of adiponectin in metabolic disorders and autoimmune diseases.

Investigation of toll-like receptor (TLR) 4 inhibitor TAK-242 as a new potential anti-rheumatoid arthritis drug.

BACKGROUND: Proper blocking of toll-like receptor (TLR) activation during disease progression has been reported to have inhibitory effect on the pathogenesis of rheumatoid arthritis (RA). We tested whether the TLR4 inhibitor TAK-242 had potential as a remedy for rheumatoid arthritis. METHODS: The therapeutic effect of TAK-242 was tested in vitro using the human rheumatoid fibroblast-like synoviocyte (FLS) line MH7A or primary human FLS and in an adjuvant-induced arthritis (AIA) rat model. RESULTS: TAK-242 dose dependently inhibited the increased expression of IL-6, IL-8, MMP-1, and VEGF in LPS-stimulated MH7A cells. It also inhibited the expression of IL-6 and IL-8 in poly(I:C), TLR3 activator-stimulated primary FLS, but not in IL-1ß-stimulated primary FLS. These findings suggest that TAK-242 blocks a specific signaling pathway to some degree. Further, TAK-242 slightly inhibited mobilization of NF-κB into nuclei. In the AIA rat model, TAK-242 significantly reversed the body weight and paw thickness of AIA rats to the normal state at a dose of 5 mg/kg, but not at 3 mg/kg, and reduced the increased serum level of IL-6 and VEGF in AIA rats. It also significantly ameliorated inflammatory symptoms of joint tissues at day 21 of treatment, according to histology and RT-PCR. CONCLUSIONS: Based on the drug repositioning concept, TAK-242, which is used for the treatment of TLR4-mediated inflammatory diseases, shows potential for cost-effective development as a remedy for rheumatoid arthritis or to control the progression of RA.

Continentalic Acid Rather Than Kaurenoic Acid Is Responsible for the Anti-Arthritic Activity of Manchurian Spikenard In Vitro and In Vivo.

The aim of this study was to identify the active compound responsible for the pharmacological activities of Manchurian spikenard (Aralia continentalis Kitag.). Interleukin (IL)-1ß-stimulated human chondrocytes and monoiodoacetate (MIA)-induced osteoarthritic rats were treated with the 50% ethanolic extract of spikenard or its major components, such as continentalic acid (ent-pimara-8(14),15-diene-19-oic acid) and kaurenoic acid (ent-kaura-16-en-19-oic acid). The spikenard extract significantly inhibited IL-1ß-stimulated production of IL-6, IL-8, metalloproteinase (MMP)-1, MMP-13, cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and prostaglandin(PG)E2 in a dose-dependent manner but not MMP-3 production. The extract also inhibited the IL-1ß-induced translocation of NF-κB/p65 into the nucleus and dose-dependent phosphorylation levels of extracellular signal-regulated kinase (ERK), Jun amino-terminal kinase (JNK) and p38 mitogen-activated protein (MAP) kinase. Continentalic acid exhibited significant anti-arthritic activity corresponding exactly to that of the extract containing an equivalent amount of continentalic acid. On the other hand, kaurenoic acid exhibited a compatible activity at about a 10-times higher molar concentration than that of continentalic acid. In vitro anti-arthritic activities of the spikenard extract and continentalic acid were also confirmed in MIA-induced osteoarthritic rats. The 50% ethanolic extract of Manchurian spikenard exhibited promising anti-arthritic activities in the in vitro and in vivo osteoarthritis models, and continentalic acid, not kaurenoic acid, was most probably responsible for those activities.

Effect of Aging on Taurine Transporter (TauT) Expression in the Mouse Brain Cortex.

Taurine content in an older brain is decreased compared to a younger brain and is associated with cognitive deficits. It is not yet known whether the decrease in taurine content is associated with decreased expression of taurine inflow mediating transporters during the aging process. In this study, we investigated whether aging affects taurine transporter and glycine transporter 1 expression in the brain cortex of the mouse. Taurine and glycine transporter expression was compared in the brain cortex of C57BL/6 mice at different ages (2, 12, and 24 months) and to age-matched NLRP3 inflammasome knockout mice. In wild type mice, taurine transporter (TauT) expression in the brain cortex of 12- or 24-month-old mice did not significantly differ from TauT expression in 2-month-old mice. Moreover, TauT expression in the brain cortex of 12- or 24-month-old mice did not significantly differ from age-matched NLRP3 KO mice. This result indirectly suggests that TauT expression may be not affected by aging or age-induced inflammation. In addition, glycine transporter expression was similar to the TauT expression pattern. In conclusion, aging and age-related inflammation might not significantly affect taurine and glycine transporter expression in aged mice. Thus, the decrease of taurine content in an older brain, which is associated with cognitive deficits, may not be significantly related to altered taurine and glycine transporter expression.

Effects of Chronic Intake of a Low Concentration of Taurine on Physical Strength and Body Composition in Mice.

Most studies of taurine on athletic performance have been conducted at acute and high doses in rodents. These doses and duration of administration are not reasonable for normal human life. Thus, it is not valid to extrapolate these animal results to people. Dose and duration that mimic human use of taurine in normal life can help to clarify the taurine effect in humans. This study investigated whether long-term, low-dose taurine (2% taurine drinking water for 25 weeks), similar to normal taurine intake in humans, can affect endurance exercise and body composition. Twenty ICR mice were divided into two groups. The control group received normal drinking water, and the taurine treated group received 2% taurine drinking water for 25 weeks. The mice were evaluated for body composition by mass and for physical strength by treadmill exhaustion and suspension tests. The supply of chronic 2% taurine drinking water has a slight effect on weight gain. In body composition analysis, a slight increase in body weight was due to an increase in muscle mass, not an increase in body fat. However, taurine ingestion did not increase endurance exercise. In conclusion, these results indirectly suggest that acute, high-dose taurine treatment is better than long-term, low-dose treatment to increase athletic performance.

A cell-penetrating peptide blocks Toll-like receptor-mediated downstream signaling and ameliorates autoimmune and inflammatory diseases in mice.

Toll-like receptors (TLRs) recognize pathogen/damage-associated molecular patterns and initiate inflammatory signaling cascades. Occasionally, overexpression of TLRs leads to the onset of numerous inflammatory diseases, necessitating the development of selective inhibitors to allow a protective yet balanced immune response. Here, we demonstrate that a novel peptide (TIP1) derived from Toll/interleukin-1 receptor (TIR) domain-containing adapter protein inhibited multiple TLR signaling pathways (MyD88-dependent and MyD88-independent) in murine and human cell lines. TIP1 also inhibited NLRP3-mediated IL-1ß secretion, as we validated at both the protein and mRNA levels. Biophysical experiments confirmed that TIP1 specifically binds to the BB loop of the TLR4-TIR domain. Animal studies revealed that TIP1 inhibited the secretion of lipopolysaccharide (LPS)-induced proinflammatory cytokines in collagen-induced arthritis (CIA) and kaolin/carrageenan-induced arthritis (K/C) rodent models. TIP1 also rescued animals from sepsis and from LPS-induced kidney/liver damage. Importantly, TIP1 ameliorated the symptoms of rheumatoid arthritis in CIA and K/C rodent models, suggesting that TIP1 has therapeutic potential for the treatment of TLR-mediated autoimmune/inflammatory diseases.