A double-blind, placebo-controlled, randomized multiple dose phase 1b trial of a CDK4/6 inhibitor, TCK-276, in patients with active rheumatoid arthritis.

OBJECTIVE: The purpose of this study was to evaluate the safety, tolerability, pharmacokinetics, and efficacy (as an exploratory endpoint) of TCK-276, a novel CDK4/6 inhibitor, after multiple oral doses for 7 days in patients with active RA. METHODS: This multicentre, randomized, placebo-controlled, dose-ascending, double-blind, phase 1b, multiple-dose study included 32 patients with active RA in 4 cohorts of 8 patients (6 active and 2 matching placebo), each receiving an oral dose of TCK-276 or matching placebo for 7 days (once daily). The doses of TCK-276 were 10, 25, 75, and 175 mg/day. Safety and pharmacokinetic endpoints, and exploratory disease activity parameters for RA were assessed. RESULTS: There were no deaths, serious adverse events, notable clinically meaningful laboratory findings (including hematological changes), clinically meaningful vital sign changes, or clinically meaningful electrocardiogram or cardiac telemetry changes. TCK-276 was rapidly absorbed and the half-life time ranged approximately from 6 to 12 hours. No obvious accumulation was observed, and the increase in TCK-276 exposure was dose proportional. At day 7, DAS28-CRP responses (EULAR good or moderate responses) were observed in 40%, 80%, and 66.7% at 25, 75, and 175 mg/day TCK-276, respectively, versus 12.5% in placebo; ACR20 responses were 33.3%, 60%, and 50% respectively, versus none in placebo. CONCLUSION: TCK-276 (≤175 mg) was well tolerated with no clinically meaningful safety signals in patients with active RA. Together with the preliminary efficacy (≥25 mg/day), these data warrant further study of TCK-276 for the treatment of active RA. TRIAL REGISTRATION: ClinicalTrails.gov, NCT05437419.

Nimesulide, a cyclooxygenase-2 selective inhibitor, suppresses obesity-related non-alcoholic fatty liver disease and hepatic insulin resistance through the regulation of peroxisome proliferator-activated receptor γ.

Cyclooxygenase (COX)-2 selective inhibitors suppress non-alcoholic fatty liver disease (NAFLD); however, the precise mechanism of action remains unknown. The aim of this study was to examine how the COX-2 selective inhibitor nimesulide suppresses NAFLD in a murine model of high-fat diet (HFD)­induced obesity. Mice were fed either a normal chow diet (NC), an HFD, or HFD plus nimesulide (HFD-nime) for 12 weeks. Body weight, hepatic COX-2 mRNA expression and triglyceride accumulation were significantly increased in the HFD group. Triglyceride accumulation was suppressed in the HFD-nime group. The mRNA expression of hepatic peroxisome proliferator-activated receptor Î³ (PPARγ) and the natural PPARγ agonist 15-deoxy-Δ12,14-prostaglandin J2 (15d­PGJ2) were significantly increased in the HFD group and significantly suppressed in the HFD-nime group. Glucose metabolism was impaired in the HFD group compared with the NC group, and it was significantly improved in the HFD-nime group. In addition, the plasma insulin levels in the HFD group were increased compared with those in the NC group, and were decreased in the HFD-nime group. These results indicate that HFD-induced NAFLD is mediated by the increased hepatic expression of COX-2. We suggest that the production of 15d-PGJ2, which is mediated by COX-2, induces NAFLD and hepatic insulin resistance by activating PPARγ. Furthermore, the mRNA expression of tissue inhibitor of metalloproteinases-1 (TIMP­1), procollagen-1 and monocyte chemoattractant protein-1 (MCP-1), as well as the number of F4/80-positive hepatic (Kupffer) cells, were significantly increased in the HFD group compared with the NC group, and they were reduced by nimesulide. In conclusion, COX-2 may emerge as a molecular target for preventing the development of NAFLD and insulin resistance in diet-related obesity.

Transplantation of freshly isolated adipose tissue-derived regenerative cells enhances angiogenesis in a murine model of hind limb ischemia.

Therapeutic angiogenesis has emerged as one of the most promising therapies for severe ischemic cardiovascular diseases with no optional therapy. Several investigators have reported that transplantation of cultured adipose-derived regenerative cells (cADRCs) to ischemic tissues promotes neovascularization and blood perfusion recovery; however, cell therapy using cultured cells has several restrictions. To resolve this problem, the angiogenic capacity of freshly isolated ADRCs (fADRCs) obtained from Lewis rats was compared with cADRCs, both in vivo and in vitro. Flow cytometric analysis showed that fADRCs contained several cell types such as endothelial progenitor cells and endothelial cells; however, these cells were present in a very small proportion in cADRCs. Transplantation of fADRCs in mice significantly improved blood perfusion, capillary density, and production of several angiogenic factors in transplanted ischemic limbs compared with a saline-injected group, whereas these effects were not observed in the cADRCs-injected group. fADRCs also showed significantly higher expression levels of angiogenic factors than cADRCs in the in vitro study. Furthermore, fADRC stimulated tube formation more remarkably than cADRC in an in vitro tube formation assay. These results suggested that fADRCs have an effective angiogenic capacity, and they would be more valuable as a source for cell-based therapeutic angiogenesis than cADRCs or other stem/progenitor cells.

Cytosolic phospholipase A2alpha contributes to blood pressure increases and endothelial dysfunction under chronic NO inhibition.

OBJECTIVE: Nitric oxide (NO) is an important modulator of cardiovascular function. In this study, we examined whether cytosolic phospholipase A2α (cPLA2α), an initial enzyme in the arachidonic acid pathway, is involved in blood pressure (BP) elevation in a murine model of chronic NO inhibition. METHODS AND RESULTS: cPLA2α gene-deficient mice (cPLA2α-/-) and wild-type mice (WT) were administered the NO synthesis inhibitor Nω-nitro-L-arginine methyl ester (L-NAME) for 4 weeks. Before treatment, BP was comparable in both groups; it increased significantly in the WT but not in the cPLA2α-/- after treatment. Bone marrow transplantation experiments showed that cPLA2α in blood cells and plasma eicosanoid concentrations were not involved in BP elevation by L-NAME treatment. Activation of cPLA2α and subsequent production of eicosanoids in the aortic endothelium but not in aortic smooth muscle cell, heart, or kidney was observed after L-NAME treatment. Aortic ring assays revealed that endothelial function was comparable in both groups of mice before treatment. L-NAME treatment disturbed endothelial function in WT but not in cPLA2α-/-. CONCLUSIONS: These results suggest that endothelial cPLA2α may play a principal role in L-NAME-induced hypertension and may be a target molecule for maintaining endothelial function under NO inhibition.

The cyclooxygenase-2 selective inhibitor, etodolac, but not aspirin reduces neovascularization in a murine ischemic hind limb model.

Cyclooxygenase inhibitors are often prescribed to relieve severe ischemic leg pain in critical ischemic limb patients. Prescription of high doses of aspirin and selective cyclooxygenase-2 inhibitors is reported to increase cardiovascular events through suppression of the vasodilative prostanoid prostaglandin I(2) in endothelium. Here, we evaluated the influence of aspirin and etodolac, a selective cyclooxygenase-2 inhibitor, on neovascularization using a murine ischemia hind limb model. C57BL/6J mice were treated with aspirin or etodolac for twenty-eight days after induction of ischemia. We exploited a concentration of the agents that suppressed cyclooxygenase activity efficiently, especially in prostaglandin I(2) production. Recovery of limb blood perfusion and capillary density in ischemic limbs was significantly suppressed by etodolac treatment when compared to the aspirin treated group and untreated group. Production of 6-keto prostaglandin F(1alpha) and prostaglandin E(2) was lower in the aspirin treated group when compared with the etodolac-treated group. Also, these concentrations were lower in both treatment groups compared with the untreated group. Immunohistochemical analysis suggested cyclooxygenase-2 was expressed in endothelium but not in inflammatory cells in ischemic tissue from the acute to chronic phase. Cyclooxygenase-1 was expressed strongly in inflammatory cells in the acute phase. Furthermore, bone marrow-derived mononuclear cell transplantation improved neovascularization, whereas aspirin and etodolac did not inhibit these effects. Production of arachidonic acid metabolites by transplanted cells was independent of the improvement of neovascularization. In conclusion, cyclooxygenase-2 inhibition reduces ischemia-induced neovascularization.