Harpagoside attenuates local bone Erosion and systemic osteoporosis in collagen-induced arthritis in mice.

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that causes local bone erosion and systemic osteoporosis. Harpagoside (HAR), an iridoid glycoside, has various pharmacological effects on pain, arthritis, and inflammation. Our previous study suggests that HAR is more deeply involved in the mechanism of bone loss caused by inflammatory stimuli than hormonal changes. Here, we identified the local and systemic bone loss inhibitory effects of HAR on RA and its intracellular mechanisms using a type 2 collagen-induced arthritis (CIA) mouse model. METHODS: The anti-osteoporosis and anti-arthritic effects of HAR were evaluated on bone marrow macrophage in vitro and CIA in mice in vivo by obtaining clinical scores, measuring hind paw thickness and inflammatory cytokine levels, micro-CT and histopathological assessments, and cell-based assay. RESULTS: HAR markedly reduced the clinical score and incidence rate of CIA in both the prevention and therapy groups. Histological analysis demonstrated that HAR locally ameliorated the destruction of bone and cartilage and the formation of pannus. In this process, HAR decreased the expression of inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-6, and IL-1ß in the serum of CIA mice. Additionally, HAR downregulated the expression of receptor activator of nuclear factor-κB ligand and upregulated that of osteoprotegerin. HAR suppressed systemic bone loss by inhibiting osteoclast differentiation and osteoclast marker gene expression in a CIA mouse model. CONCLUSIONS: Taken together, these findings show the beneficial effect of HAR on local symptoms and systemic bone erosion triggered by inflammatory arthritis.

[Therapeutic mechanism of Psammosilene tunicoides extract on rheumatoid arthritis based on NLRP3 inflammasome].

In this study, we investigated the mechanism of crude extract of Psammosilene tunicoides(CEPT) in the treatment of rheumatoid arthritis(RA) based on the Nod-like receptor protein 3(NLRP3) inflammasome. The collagen-induced arthritis(CIA) mouse model was established. On day 32 after the primary immunization, according to the arthritis score, the mice were randomly divided into model group, positive control(methotrexate) group, low-and high-dose CEPT groups, and normal group, with 10 mice in each group. According to the administration dose of each group, the mice were continuously administered for 21 days. Every four days during the administration, the paw edema degree, arthritis score, and spleen index of the mice were measured; histopathological examination was performed for the ankles of the mice; the contents of IL-1ß and IL-18 in the serum were determined; the protein expression levels of NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a CARD(ASC), as well as the mRNA expression levels of NLRP3 and caspase-1 in the ankle joints of the mice were detected. The results showed that compared with those in the model group, the mice in the positive control group and CEPT groups had significantly decreased the contents of IL-1ß and IL-18 in the serum and spleen index(P<0.01), significantly lowered arthritis score and degree of paw edema(P<0.01), alleviated arthritic infiltration of the knee, and down-regulated protein and mRNA levels of NLRP3, ASC, and caspase-1 in the ankle joint(P<0.01). These results suggest that P. tunicoides may reduce the paw edema and arthritis score and alleviate the inflammatory response in CIA mice by inhibiting the expression of NLRP3. This study provides a basis for the study of immune regulation of P. tunicoides in RA.

Allicin regulates Treg/Th17 balance in mice with collagen-induced arthritis by increasing the expression of MEKK2 protein.

To study the role of Allicin in regulating Treg/Th17 ratio in splenic lymphocyte by increasing the expression of MEKK2 protein in MAPK signaling pathway, and to explore the mechanism of immune response in mice with collagen-induced arthritis (CIA). Mouse CIA model was induced by chicken collagen type II, and experimental mice were randomly divided into NC group, Model group, and Allicin group. HE staining was used to compare the degree of joint pathological damage in mice of each group, and Masson staining to observe the proliferation of collagen tissue in each group. Flow cytometry detected Treg/Th17 ratio in splenic lymphocytes. Furthermore, RT-PCR and WB were used to detect the mRNA and protein expression of related transcription factors and inflammatory factors Foxp3, ROR-γt, and IL-17A, as well as MEK2 protein expression in splenic lymphocytes. The results showed that Allicin treatment could reduce the severity of arthritis and the proliferation of collagen fibers on the surface of cartilage and bone joints in CIA mice. Compared with NC group, Treg decreased and Th17 increased in spleen lymphocyte of Model group (p < .01); after Allicin treatment, Treg increased while Th17 decreased significantly (p < .01). Meanwhile, MEKK2 protein expression in spleen lymphocyte of Model group decreased compared to that in NC group (p < .01), and MEK2 protein expression increased significantly after Allicin treatment (p < .01). To sum up, the present study suggests that MEKK2 protein plays an important role in the pathogenesis of CIA model. In terms of mechanism, Allicin may play a therapeutic role in rheumatoid arthritis (RA) by increasing the expression of MEKK2 protein and affecting Treg/Th17 ratio.

JTP-117968, a novel selective glucocorticoid receptor modulator, exhibits significant anti-inflammatory effect while maintaining bone mineral density in mice.

Classic glucocorticoids have been prescribed for various inflammatory diseases, such as rheumatoid arthritis, due to their outstanding anti-inflammatory effects. However, glucocorticoids cause numerous unwanted side effects, including osteoporosis and diabetes. Hence, selective glucocorticoid receptor modulators (SGRMs), which retain anti-inflammatory effects with minimized side effects, are among the most anticipated drugs in the clinical field. The assumption is that there are two major mechanisms of action via glucocorticoid receptors, transrepression (TR) and transactivation (TA). In general, anti-inflammatory effects of glucocorticoids are largely due to TR, while the side effects associated with glucocorticoids are mostly mediated through TA. We previously reported that JTP-117968, a novel SGRM, maintained partial TR activity while remarkably reducing the TA activity. In this study, we investigated the anti-inflammatory effect of JTP-117968 on a lipopolysaccharide (LPS) challenge model and collagen-induced arthritis (CIA) model in mice. Meanwhile, we tested the effect of JTP-117968 on the bone mineral density (BMD) in mouse femur to evaluate the side effect. Based on the evaluation, JTP-117968 reduced the plasma levels of tumor necrosis factor α induced by LPS challenge in mice significantly. Remarkably, CIA development was suppressed by JTP-117968 comparably with prednisolone and PF-802, an active form of fosdagrocorat that has been developed clinically as an orally available SGRM. Strikingly, the side effect of JTP-117968 on mouse femoral BMD was much lower than those of PF-802 and prednisolone. Therefore, JTP-117968 has attractive potential as a new therapeutic option against inflammatory diseases with minimized side effects compared to classic glucocorticoids.

Therapeutic mechanism of Psammosilene tunicoides extract on rheumatoid arthritis based on NLRP3 inflammasome / 中国中药杂志

In this study, we investigated the mechanism of crude extract of Psammosilene tunicoides(CEPT) in the treatment of rheumatoid arthritis(RA) based on the Nod-like receptor protein 3(NLRP3) inflammasome. The collagen-induced arthritis(CIA) mouse model was established. On day 32 after the primary immunization, according to the arthritis score, the mice were randomly divided into model group, positive control(methotrexate) group, low-and high-dose CEPT groups, and normal group, with 10 mice in each group. According to the administration dose of each group, the mice were continuously administered for 21 days. Every four days during the administration, the paw edema degree, arthritis score, and spleen index of the mice were measured; histopathological examination was performed for the ankles of the mice; the contents of IL-1β and IL-18 in the serum were determined; the protein expression levels of NLRP3, caspase-1, and apoptosis-associated speck-like protein containing a CARD(ASC), as well as the mRNA expression levels of NLRP3 and caspase-1 in the ankle joints of the mice were detected. The results showed that compared with those in the model group, the mice in the positive control group and CEPT groups had significantly decreased the contents of IL-1β and IL-18 in the serum and spleen index(P<0.01), significantly lowered arthritis score and degree of paw edema(P<0.01), alleviated arthritic infiltration of the knee, and down-regulated protein and mRNA levels of NLRP3, ASC, and caspase-1 in the ankle joint(P<0.01). These results suggest that P. tunicoides may reduce the paw edema and arthritis score and alleviate the inflammatory response in CIA mice by inhibiting the expression of NLRP3. This study provides a basis for the study of immune regulation of P. tunicoides in RA.

Theaflavin-3, 3'-Digallate Attenuates Rheumatoid Inflammation in Mice Through the Nuclear Factor-κB and MAPK Pathways.

Rheumatoid arthritis (RA) is a common autoimmune disease which impacts a large number of patients worldwide, and new drugs are required for lower the disease burden. Theaflavin-3, 3'-digallate (TFDG) is polyphenol exhibiting inhibition on inflammatory factors. This study aimed to explore the attenuation of TFDG on RA. The collagen-induced arthritis (CIA) mouse model was established and administered with TFDG. The arthritis score and incidence was recorded to assess the amelioration of TFDG on arthritis. Histopathological change of the mouse joint tissues was evaluated by haemotoxylin and eosin staining. The expression of pro-inflammatory mediators including interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, and IL-6 was quantified by ELISA. The activation of nuclear factor (NF)-κB and mitogen-activated protein kinase (MAPK) signaling pathways in the synovium were determined by Western blotting. In comparison with the control, administration of TFDG significantly reduced arthritis score and incidence in the CIA mouse model. TFDG significantly suppressed the expression of IL-1ß, TNF-α, and IL-6, as well as the levels of MMP-1, MMP-2, and MMP-3 in the synovium. TFDG also showed remarkable inhibition on the activation of NF-κB and the phosphorylation of P38, JNK2, and ERK. This study puts up evidence that TFDG exerts protection on RA via inhibiting the activation of NF-κB- and MAPK-signaling pathways.

Comparison of Improvement Effects and Its Mechanism of Different Doses of Total Alkaloids from Aconitum racemulosum on CIA Model Rats Based on Information Entropy Theory / 中国药房

OBJECTIVE： To investigate the effects of different doses of total alkaloids from Aconitum racemulosum （ARTA） on serum inflammation factors and FOS protein expression in synovial tissue of joint in collagen-induced arthritis （CIA） model rats， and to investigate its potential mechanism of anti-rheumatoid arthritis （RA）. METHODS： Male SD rats were randomly divided into blank group， model group， positive group （Compound dexamethasone acetate ointment， 0.2 g/kg）， ARTA low-dose， medium-dose and high-dose groups （56.26， 112.50， 225.00 mg/kg， by the weight of ARTA in the extract）， with 10 rats in each group. Except for blank group， other groups were given subcutaneous injection of Bovine collagen Ⅱ emulsified with incomplete Freund’s adjuvant into the left foot to establish CIA model； the left foot were smeared with relevant medicine from the day of modeling. Blank group and model group were smeared with constant volume of 65％ ethanol， 3 times a day， for consecutive 28 days. On the 7th， 14th， 21st and 28th day of administration， the thickness of left hind toe was measured with vernier caliper， and the degree of foot swelling was calculated. The serum contents of IL-1β， IL-6 and TNF-α in rats were measured by ELISA after last administration. The expression of FOS protein in synovial tissue was determined by immunohistochemical method [expressed by HIS]. The comprehensive score was conculated by entropy weight method. Effects of each dosage on above indexes of CIA model rats were evaluated with the comprehensive score. RESULTS： Compared with blank group， the degree of foot swelling， serum content of inflammatory factors and HIS value were increased significantly in model group （P＜0.05）. Compared with model group， the degree of foot swelling in each administration group， serum contents of IL-1β， IL-6 and TNF-α， HIS in positive group and ARTA high-dose group， serum contents of IL-6 and TNF-α in ARTA medium-dose group as well as serum content of TNF-α in ARTA low-dose group were decreased significantly（P＜0.05）. Comprehensive score of above indicators were 0.37（positive group）， 0.31（ARTA high-dose group）， 0.23（ARTA medium-dose group） and 0.09（ARTA low-dose group）. CONCLUSIONS： ARTA can improve CIA model rats， and the effect tends to increase with the increase of dose. Above effect may be associated with reducing serum content of inflammatory factors and inhibiting the expression of FOS protein in synovial tissue.

Proceedings of the 2017 National Toxicology Program Satellite Symposium.

The 2017 annual National Toxicology Program Satellite Symposium, entitled "Pathology Potpourri," was held in Montreal, Quebec, Canada at the Society of Toxicologic Pathology's 36th annual meeting. The goal of this symposium was to present and discuss challenging diagnostic pathology and/or nomenclature issues. This article presents summaries of the speakers' talks along with select images that were used by the audience for voting and discussion. Various lesions and other topics covered during the symposium included renal papillary degeneration in perinatally exposed animals, an atriocaval mesothelioma, an unusual presentation of an alveolar-bronchiolar carcinoma, a paraganglioma of the organ of Zuckerkandl (also called an extra-adrenal pheochromocytoma), the use of human muscle samples to illustrate the challenges of manual scoring of fluorescent staining, intertubular spermatocytic seminomas, medical device pathology assessment and discussion of the approval process, collagen-induced arthritis, incisor denticles, ameloblast degeneration and poorly mineralized enamel matrix, connective tissue paragangliomas, microcystin-LR toxicity, perivascular mast cells in the forebrain thalamus unrelated to treatment, and 2 cases that provided a review of the International Harmonization of Nomenclature and Diagnostic Criteria (INHAND) bone nomenclature and recommended application of the terminology in routine nonclinical toxicity studies.

CZ415, a Highly Selective mTOR Inhibitor Showing in Vivo Efficacy in a Collagen Induced Arthritis Model.

CZ415, a potent ATP-competitive mTOR inhibitor with unprecedented selectivity over any other kinase is described. In addition to a comprehensive characterization of its activities in vitro, in vitro ADME, and in vivo pharmacokinetic data are reported. The suitability of this inhibitor for studying in vivo mTOR biology is demonstrated in a mechanistic mouse model monitoring mTOR proximal downstream phosphorylation signaling. Furthermore, the compound reported here is the first ATP-competitive mTOR inhibitor described to show efficacy in a semitherapeutic collagen induced arthritis (CIA) mouse model.

The expression of TIPE2 and its role in the pathogenesis of rheumatoid arthritis / 中华微生物学和免疫学杂志

Objective To investigate the expression of TIPE2 in splenic lymphocytes derived from the mouse model of cattle collagen Ⅱ-induced rheumatoid arthritis (CIA) and from peripheral blood of patients with rheumatoid arthritis (RA) for its role in the pathogenesis of RA.Methods The CIA mouse model was established by immunization of DBA-1/J mice with cattle collagen Ⅱ.Peripheral blood lymphocytes were collected from RA patients and healthy donors.The TIPE2 mRNA and protein expression in splenocytes of CIA and control mice were measured by semi-quantitative RT-PCR and Western blot,respectively.In addition,fluorescence quantitative RT-PCR and Western blot were used to determine the TIPE2 mRNA and protein expression in peripheral blood lymphocytes derived from patients with RA and healthy donors.Results Both mRNA and protein expression of TIPE2 were higher in splenocytes of CIA mice and lymphocytes of peripheral blood from RA patients compared with corresponding controls.Furthermore,the mRNA and protein expression of TIPE2 increased significantly in patients with active RA.TIPE2 expression were positively correlated with DAS28 scores (P＜0.001).Conclusion Our results suggest that TIPE2 plays a role in the RA pathogenesis.The level of TIPE2 may also indicate the severity of rheumatoid arthritis.

Study on establishing type Ⅱ collagen induced arthritis model in rats / 中国免疫学杂志

Objective:Research on establishing a better experimental arthritis rat model of cold-dampness arthraligia on rheumatoid arthritis(RA) research.Methods:In order to induce arthritis,the rat's feet were injected with different concentrations of type Ⅱ collagen mixed with Freund's adjuvant;measure the feet swelling degrees of rats,then calculated swelling rate;detect the level of serum sialic acid(SA);observ the synovial histopathology and ultrastructural of rats.Results:The rat joints swell of the group with low concentration of type Ⅱ collagen and completed Freund's adjuvant was rapid and severe,while that of the group with high concentration of type Ⅱ collagen and incompleted Freund's adjuvant was moderate and lasting.The level of serum SA of model groups was higher than the normal group.The histopathology changes of rat's synovium conform to RA.Conclusion:The group injected with high concentration of type Ⅱ collagen and incompleted Freund's adjuvant is the ideal RA model.It is belonged to the symptom of cold-dampness arthralgia,compared with this model,the AA approaches the symptom of heat-dampness arthralgia.