Anti-adipogenic effects of KD025 (SLx-2119), a ROCK2-specific inhibitor, in 3T3-L1 cells.

Adipose tissue is a specialized organ that synthesizes and stores fat. During adipogenesis, Rho and Rho-associated kinase (ROCK) 2 are inactivated, which enhances the expression of pro-adipogenic genes and induces the loss of actin stress fibers. Furthermore, pan ROCK inhibitors enhance adipogenesis in 3T3-L1 cells. Here, we show that KD025 (formerly known as SLx-2119), a ROCK2-specific inhibitor, suppresses adipogenesis in 3T3-L1 cells partially through a ROCK2-independent mechanism. KD025 downregulated the expression of key adipogenic transcription factors PPARγ and C/EBPα during adipogenesis in addition to lipogenic factors FABP4 and Glut4. Interestingly, adipogenesis was blocked by KD025 during days 1~3 of differentiation; after differentiation terminated, lipid accumulation was unaffected. Clonal expansion occurred normally in KD025-treated cells. These results suggest that KD025 could function during the intermediate stage after clonal expansion. Data from depletion of ROCKs showed that KD025 suppressed cell differentiation partially independent of ROCK's activity. Furthermore, no further loss of actin stress fibers emerged in KD025-treated cells during and after differentiation compared to control cells. These results indicate that in contrast to the pro-adipogenic effect of pan-inhibitors, KD025 suppresses adipogenesis in 3T3-L1 cells by regulating key pro-adipogenic factors. This outcome further implies that KD025 could be a potential anti-adipogenic/obesity agent.

Relationships among medication adherence, insight, and neurocognition in chronic schizophrenia.

AIMS: In order to improve long-term prognosis in schizophrenia, enhancing medication adherence is essential. The aim of this study was thus to identify the association between medication non-adherence and possible risk factors in a large sample of patients with chronic schizophrenia. METHODS: One hundred and four patients with schizophrenia with a disease duration of over 10 years were enrolled in this cross-sectional study. The subjects were assessed with the Scale to Assess Unawareness of Mental Disease-Korean version, the Korean version of the Medication Adherence Rating Scale, a neurocognition battery designed for this study, and the Positive and Negative Symptoms Scale. An anova and multiple regression models were conducted to identify the correlations among variables and the factors that contribute to medication adherence. RESULTS: The adherence score measured on the Korean version of the Medication Adherence Rating Scale was 7.60 ± 2.12; 88 (84.62%) patients were categorized as well-adherent and 16 (15.38%) as poorly adherent to their medication. Patients with good insight were more likely to maintain their medication (P = 0.0005), and better executive function was associated with increased medication adherence (P = 0.0008). Furthermore, fewer depressive symptoms were associated with good medication adherence (P = 0.0304). CONCLUSIONS: This study is the first in the Republic of Korea to identify the relationship between medication adherence, insight, and neurocognition in a large sample of patients with chronic schizophrenia. These results could be used to establish a strategy for improving the prognosis of chronic schizophrenia.

MicroRNA-494, upregulated by tumor necrosis factor-α, desensitizes insulin effect in C2C12 muscle cells.

Chronic inflammation is fundamental for the induction of insulin resistance in the muscle tissue of vertebrates. Although several miRNAs are thought to be involved in the development of insulin resistance, the role of miRNAs in the association between inflammation and insulin resistance in muscle tissue is poorly understood. Herein, we investigated the aberrant expression of miRNAs by conducting miRNA microarray analysis of TNF-α-treated mouse C2C12 myotubes. We identified two miRNAs that were upregulated and six that were downregulated by a >1.5-fold change compared to normal cells. Among the findings, qRT-PCR analysis confirmed that miR-494 is consistently upregulated by TNF-α-induced inflammation. Overexpression of miR-494 in CHO(IR/IRS1) and C2C12 myoblasts suppressed insulin action by down-regulating phosphorylations of GSK-3α/ß, AS160 and p70S6K, downstream of Akt. Moreover, overexpression of miR-494 did not regulate TNF-α-mediated inflammation . Among genes bearing the seed site for miR-494, RT-PCR analysis showed that the expression of Stxbp5, an inhibitor of glucose transport, was downregulated following miR-494 inhibition. In contrast, the expression of PTEN decreased in the cells analyzed, thus showing that both positive and negative regulators of insulin action may be simultaneously controlled by miR-494. To investigate the overall effect of miR-494 on insulin signaling, we performed a PCR array analysis containing 84 genes related to the insulin signaling pathway, and we observed that 25% of genes were downregulated (P<0.05) and 11% were upregulated (P<0.05). These results confirm that miR-494 might contribute to insulin sensitivity by positive and negative regulation of the expression of diverse genes. Of note, PCR array data showed downregulation of Slc2A4, a coding gene for Glut4. Altogether, the present study concludes that the upregulation of miR-494 expression by TNF-α-mediated inflammation exacerbates insulin resistance. Therefore, we suggest that miR-494 could prove an important target for the diagnosis and therapy of inflammation-mediated insulin resistance in muscle.