The protective effect of rabeprazole on cisplatin-induced apoptosis and necroptosis of renal proximal tubular cells.

Nephrotoxicity is a major adverse reaction of cisplatin-based chemotherapy. Organic cation transporter 2 (OCT2) which is located on the basement membrane of human proximal renal tubules is responsible for the renal accumulation of cisplatin and its nephrotoxicity. This study aimed to investigate the protective effect of PPIs to CP-induced nephrotoxicity. Three kinds of PPIs including lansoprazole, omeprazole and rabeprazole (Rab) were co-administrated with CP to mice. In addition, OCT2-overexpressed HEK293, HK-2 and A549 cells were co-incubated with CP and PPIs. The results showed that PPIs can attenuate CP-induced increase of CRE, BUN and histological damage of kidney. Among the three PPIs, Rab was found with a superior protective effect. It significantly reduced the accumulation of CP in OCT2-overexpressed HEK293 cells and in the renal cortex tissues of mice, but not in HK-2 cells. Moreover, Rab reduced the expression levels of cleaved-caspase-3, RIPK1, RIPK3, MLKL and p-MLKL and the apoptosis rate of renal tubular cells induced by CP in vivo, but not in HK-2 cells. However, Rab increased the viability of CP-treated cells in a concentration-dependent manner and attenuated CP-induced apoptosis and necroptosis in OCT2 over-expressed HEK293 cells. Finally, we demonstrated that Rab have no influence on the antitumor effect of CP. In conclusion, Rab attenuate CP-induced nephrotoxicity mainly through inhibiting OCT2-mediated CP uptake, without interfering with its anti-tumor property of inducing apoptosis and necroptosis.

Targetted inhibition of CD74 attenuates adipose COX-2-MIF-mediated M1 macrophage polarization and retards obesity-related adipose tissue inflammation and insulin resistance.

Adipose tissue (AT) inflammation is crucial to the development of obesity-associated insulin resistance. Our aim was to investigate the contribution of cyclooxygenase-2 (COX-2)/macrophage migration inhibitory factor (MIF)-mediated cross-talk between hypertrophic adipocytes and macrophages to the etiology of AT inflammation and the involvement of CD74 using human SGBS adipocytes, THP-1 macrophages and mice fed a high-fat (HF) diet. The MIF and CD74 mRNA levels in the adipocytes and stromal vascular cells (SVCs) of white fat were highly correlated with body weight (BW), homeostatic model assessment for insulin resistance (HOMA-IR), and adipose macrophage marker expression levels, especially those in SVCs. COX-2 inhibition suppressed the elevation of MIF production in HF white adipocytes as well as palmitate and hypoxic-treated SGBS adipocytes. Treatment of adipocytes transfected with shCOX-2 and siMIF or subjected to MIF depletion in the medium reversed the pro-inflammatory responses in co-incubated THP-1 cells. Inhibition of NF-κB activation reversed the COX2-dependent MIF secretion from treated adipocytes. The targetted inhibition of macrophage CD74 prevented M1 macrophage polarization in the above co-culture model. The COX-2-dependent increases in CD74 gene expression and MIF release in M1-polarized macrophages facilitated the expression of COX-2 and MIF in co-cultured SGBS adipocytes. CD74 shRNA intravenous injection suppressed HF-induced AT M1 macrophage polarization and inflammation as well as insulin resistance in mice. The present study suggested that COX-2-mediated MIF secretion through NF-κB activation from hypertrophic and hypoxic adipocytes as well as M1 macrophages might substantially contribute to the phenotypic switch of AT macrophages through CD74 in obesity. Inhibition of CD74 could attenuate AT inflammation and insulin resistance in the development of HF diet-induced obesity.

Antidepressant-like effect of geniposide on chronic unpredictable mild stress-induced depressive rats by regulating the hypothalamus-pituitary-adrenal axis.

Geniposide as the major active component of Gardenia jasminoides Ellis has neuroprotective activity. This study elucidated the potential antidepressant-like effect of geniposide and its related mechanisms using a depression rat model induced by 3 consecutive weeks of chronic unpredictable mild stress (CUMS). Sucrose preference test, open field test (OFT) and forced swimming test (FST) were applied to evaluate the antidepressant effect of geniposide. Adrenocorticotropic hormone (ACTH) and corticosterone (CORT) serum levels, adrenal gland index and hypothalamic corticotrophin-releasing hormone (CRH) mRNA expression were measured to assess the activity of hypothalamus-pituitary-adrenal (HPA) axis. Hypothalamic glucocorticoid receptor α (GRα) mRNA expression and GRα protein expression in hypothalamic paraventricular nucleus (PVN) were also determined by real-time PCR and immunohistochemistry, respectively. We found that geniposide (25, 50, 100mg/kg) treatment reversed the CUMS-induced behavioral abnormalities, as suggested by increased sucrose intake, improved crossing and rearing behavior in OFT, shortened immobility and prolonged swimming time in FST. Additionally, geniposide treatment normalized the CUMS-induced hyperactivity of HPA axis, as evidenced by reduced CORT serum level, adrenal gland index and hypothalamic CRH mRNA expression, with no significant effect on ACTH serum level. Moreover, geniposide treatment upregulated the hypothalamic GRα mRNA level and GRα protein expression in PVN, suggesting geniposide could recover the impaired GRα negative feedback on CRH expression and HPA axis. These aforementioned therapeutic effects of geniposide were essentially similar to fluoxetine. Our results indicated that geniposide possessed potent antidepressant-like properties that may be mediated by its effects on the HPA axis.

Expression of hedgehog signal pathway in articular cartilage is associated with the severity of cartilage damage in rats with adjuvant-induced arthritis.

BACKGROUND: Cartilage damage is a crucial step in rheumatoid arthritis (RA) disease progress while its molecular mechanisms are not fully understood. Here we investigated the expression of hedgehog (Hh) signal pathway in articular cartilage of adjuvant-induced arthritis (AIA) rats and its possible pathological role in cartilage damage. METHODS: 30 rats were divided into sham and AIA group (n = 15). Complete Freund's adjuvant was used to induce AIA. Secondary paw swelling was measured on day 10, 14, 18, 22 and 26 after induction. Rats were sacrificed on day 26 and knee joints and cartilage tissues were collected. Paw swelling, cartilage histopathologic changes and OARSI scores were used to evaluate AIA in rats. The protein expression of Hh signal related genes (Shh, Ptch1, Smo and Gli1) in cartilage were assayed by immunohistochemistry. The mRNA levels of Shh, Ptch1, Smo, Gli1, type-II collagen (COII) and aggrecan in cartilage were assayed by real-time PCR. In vitro study, cultured AIA chondrocytes were treated with cyclopamine (a specific inhibitor of Hh signal) and the mRNA levels of Hh signal and ECM components (COII and aggrecan) were measured by real-time PCR. RESULTS: Immunohistochemical results revealed that Shh, Ptch1, Smo and Gli1 proteins showed higher expression in the articular cartilage of AIA rats than those of sham rats. Real-time PCR results confirmed that Shh, Ptch1, Smo and Gli1 mRNA levels in cartilage tissues of AIA rats were significantly increased compared with those of sham rats (1.6, 1.4, 1.6, 2.0 fold, respectively). The mRNA levels of Shh, Ptch1, Smo, and Gli1 were associated with the severity of cartilage damage (indicated by OARSI scores, COII and aggrecan mRNA levels in cartilage). In vitro, cyclopamine effectively decreased the mRNA levels of Shh, Ptch1, Smo and Gli1, and increased the mRNA levels of COII and aggrecan in AIA chondrocytes, suggesting Hh signal inhibition might directly promote ECM production. CONCLUSIONS: Our findings present certain experimental evidence that Hh signal pathway is involved in the pathogenesis of cartilage damage in RA.

Inhibition of hedgehog signal pathway by cyclopamine attenuates inflammation and articular cartilage damage in rats with adjuvant-induced arthritis.

OBJECTIVES: We investigated whether inhibition of hedgehog (Hh) signal by cyclopamine attenuated inflammation and cartilage damage in adjuvant-induced arthritis (AIA) rats. METHODS: Cyclopamine (2.5, 5, 10 mg/kg) was given by intraperitoneal injection once daily from day 12 to 21 after AIA induction. Paw swelling (volume changes), serum pro-inflammatory cytokines levels (ELISA), histological analysis of joint damage (H&E staining), proteoglycans expression (Alcian blue staining), mRNA levels of sonic Hh (Shh), glioma-associated oncogene homologue 1 (Gli1), type II collagen (COII) and aggrecan in cartilage (real-time PCR) and articular chondrocyte apoptosis (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling) were measured respectively. KEY FINDINGS: Cyclopamine effectively attenuated inflammation and cartilage damage of AIA rats, as evidenced by reduced paw swelling, serum levels of tumor necrosis factors (TNF)-α, IL-1ß, IL-6 and histological scores of joint damage, increased proteoglycans expression and mRNA levels of COII and aggrecan in articular cartilage. Shh or Gli1 mRNA level was correlated negatively with COII and aggrecan mRNA levels, suggesting Hh signal inhibition was associated with promotion of cartilage extracellular matrix production. Furthermore, cyclopamine decreased the number of apoptotic articular chondrocytes of AIA rats, which might be partly related to its mechanisms on relieving cartilage damage. CONCLUSIONS: Our findings present some experimental evidence that Hh signal inhibition might be of potential clinical interest in rheumatoid arthritis treatment.

[Effect of hesperidin on behavior and HPA axis of rat model of chronic stress-induced depression].

OBJECTIVE: To observe the effect of hesperidin on behavior and hypothalamic-pituitary-adrenal (HPA) axis of ratmodel of chronic stress-induced depression. METHOD: Chronic unpredictable mild stress (CUMS) was used to establish the rat depression model. Sixty male SD rats were divided randomly into six groups: the normal group, the model group, the hesperidin (40, 80, 160 mg x kg(-1)) group and the positive fluoxetine (10 mg x kg(-1)) group. They were orally administered with drugs for three weeks. The sucrose preference test and the forced swimming test (FST) were assayed to detect animal behavior. The levels of corticosterone (CORT) in serum, mRNA of corticotropin release factor (CRF) in hypothalamus as well as protein expression of glucocorticoid receptor (GR) in paraventricular nucleus (PVN) were determined to clarify the anti-depression effect and mechanism of hesperidin. RESULT: Compared with the model group, rats in the hesperidin (40, 80, 160 mg x kg(-1)) treatment group showed significant increase in the sucrose consumption and decrease in the immobility time in FST to varying degrees. Meanwhile, the excessively high serum CORT and adrenal index of CUMS rats were reversed by treatment with hesperidin. In addition, hesperidin inhibited CRF mRNA expression in hypothalamus and up-regulated GR protein expression in PVN among CUMS rats. CONCLUSION: Hesperidin could effectively improve the behavior of CUMS rats and show the anti-depression effect. Its mechanisms may be related to the function of regulating HPA axis.

7,3'-dimethoxy hesperetin inhibits inflammation by inducing synovial apoptosis in rats with adjuvant-induced arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by pronounced inflammation and excessive synovial hyperplasia within affected joint. We previously reported 7, 3'-dimethoxy hesperetin (DMHP) as a highly anti-inflammatory active derivative of hesperidin showed apparent pro-apoptotic effect in vitro on fibroblast-like synoviocytes of rats with adjuvant arthritis (AA), an animal model of RA. Here, we investigated the therapeutic effects of DMHP on inflammation and synovial apoptosis in rats with AA in vivo. Paw swelling, arthritis index, TNF-α and IL-1ß serum levels were measured to evaluate the effect of DMHP on inflammation in AA rats. DNA ladder detection and TUNEL assay were used to investigate the pro-apoptotic effect of DMHP on synovial apoptosis in vivo. Bcl-2, Bax mRNA and protein expressions in synovium were determined by real-time Q-PCR and western blot, respectively. We found DMHP inhibited secondary hind paw swelling and arthritis index, and decreased TNF-α and IL-1ß serum levels in AA rats. Typical DNA ladder formation was found in DNA extraction of synovium from DMHP treated groups. The number of apoptotic synovial cells was elevated with DMHP treatment in TUNEL assay. DMHP markedly decreased Bcl-2 expression whereas increased Bax expression in synovium of AA rats at both transcription and protein levels. Moreover, DMHP treatment on AA rats significantly decreased the protein ratio of Bcl-2/Bax in synovium. In conclusion, DMHP has an apparent therapeutic effect on inflammation in rats with AA. Mechanisms of this effect are partly related to induction of synovial apoptosis through modulation of Bcl-2 and Bax expression.