Effects and related mechanisms of histone deacetylase inhibitors on the proliferation of choroidal melanoma C918 cell line / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To elucidate the effect of histone deacetylase(HDAC)inhibitor suberoylanilide hydroxamic acid(SAHA)on the proliferation of choroidal melanoma(CM)cell line C918 and to explore the related mechanism.METHODS: Inverted fluorescence microscope was used to observe the effect of different concentrations of SAHA(0.625, 1.25 or 2.5 μmol/L)on the morphology of C918 cell. The cell viability was detected by cholecystokinin octapeptide(CCK-8)assay. Plate clone formation assay and EdU staining were carried out to measure the effect of SAHA on the cell proliferation. Meanwhile, the expressions of cell proliferation-related proteins including c-Myc, CyclinA2 and CDK2, and histone deacetylase 7(HDAC7)and fibroblast growth factor 18(FGF18)were detected by Western blot.RESULTS: Compared with the control group, the cell density was reduced in SAHA. SAHA could also promote cell shrinkage, and the inhibition on cell was in a concentration-dependent manner. CCK-8 assay showed that SAHA treatment decreased cell viability in a dose-dependent manner and the inhibition rate was 80% when SAHA at 2.5 μmol/L. Compared with the control group, Western blot showed that SAHA could suppress the expression of cell proliferation proteins including c-Myc, CyclinA2 and CDK2 in a dose-dependent manner. In addition, 1.25 μmol/L SAHA significantly decreased the numbers of EdU staining positive cells and cell clones. More importantly, SAHA could dose-dependently decrease the expression of HDAC7 and FGF18 compared with control group.CONCLUSION: SAHA could inhibit the proliferation of CM cell line C918 by inhibiting the HDAC7/FGF18 signaling pathway.

Observation of panobinostat alleviates early brain injury in subarachnoid hemorrhage model / 中国基层医药

Objective To observe the effect of panobinostat (LBH589) on the early brain injury (EBI) in the model of subarachnoid hemorrhage(SAH) in SD rats.Methods SD rats were randomly divided into 4 groups:sham(10 rats) and SAH(10 rats),SAH + vehicle(20 rats) and SAH + Panobinostat (20 rats).Drug or vehicle was given by lateral-ventricular stereotaxic injection 24h before the SAH model was introduced.Water contents and the neurological scores were determined at 24h post-SAH.The levels of Ac-H3K27 in frontal and lateral lobe were detected by Western blot.Results The mean neurological score of the SAH group was higher than that of the sham group(F =13.000,P =0.007).The water content of the SAH group was higher than that of the sham group (F =8.229,P =0.019).The level of Ac-H3K27 was higher in the SAH + Panobinostat group than that in the SAH +vehicle group(F =41.250,P =0.000).The mean neurological score of the SAH + Panobinostat group was lower than that of the SAH + vehicle group(F =9.560,P =0.011).The water content of the SAH + Panobinostat group was lower than that of the SAH + vehicle group (F =8.211,P =0.020).The correlation analysis indicated that the level of acetylation of H3 was negatively correlated with the neurological score (r =-0.585,P =0.046).Conclusion Panobinostat can improve the neurological behavior and alleviate early brain injury in the SAH model.

HDAC Inhibition by Valproic Acid Induces Neuroprotection and Improvement of PD-like Behaviors in LRRK2 R1441G Transgenic Mice

Parkinson’s disease (PD) is one of the late-onset neurodegenerative movement disorder. Major pathological markers of PD include progressive loss of dopaminergic neurons, Lewy body formation, genetic mutations, and environmental factors. Epigenetic regulation of specific gene expression via impaired histone acetylation is associated with neuronal dysfunction in various neurodegenerative diseases. In this study, we hypothesized that histone deacetylase (HDAC) inhibitor, valproic acid (VPA), can improve motor function by enhancing cell survival in PD genetic model mice with LRRK2 R1441G mutation. To address this question, we administered VPA in LRRK2 R1441G transgenic mice to determine whether VPA affects 1) histone acetylation and HDAC expression, 2) dopaminergic neuron survival, 3) inflammatory responses, 4) motor or non-motor symptoms. As results, VPA administration increased histone acetylation level and the number of tyrosine hydroxylase (TH) positive neurons in substantia nigra of LRRK2 R1441G mice. VPA reduced iba-1 positive activated microglia and the mRNA levels of pro-inflammatory marker genes in LRRK2 R1441G mice. In addition, VPA induced the improvement of PD-like motor and non-motor behavior in LRRK2 R1441G mice. These data suggest that the inhibition of HDAC can be further studied as potential future therapeutics for PD.

Observation of panobinostat alleviates early brain injury in subarachnoid hemorrhage model / 中国基层医药

Objective@#To observe the effect of panobinostat (LBH589) on the early brain injury (EBI) in the model of subarachnoid hemorrhage(SAH) in SD rats.@*Methods@#SD rats were randomly divided into 4 groups: sham(10 rats) and SAH(10 rats), SAH+ vehicle(20 rats) and SAH+ Panobinostat(20 rats). Drug or vehicle was given by lateral-ventricular stereotaxic injection 24h before the SAH model was introduced.Water contents and the neurological scores were determined at 24h post-SAH.The levels of Ac-H3K27 in frontal and lateral lobe were detected by Western blot.@*Results@#The mean neurological score of the SAH group was higher than that of the sham group(F=13.000, P=0.007). The water content of the SAH group was higher than that of the sham group (F=8.229, P=0.019). The level of Ac-H3K27 was higher in the SAH+ Panobinostat group than that in the SAH+ vehicle group(F=41.250, P=0.000). The mean neurological score of the SAH+ Panobinostat group was lower than that of the SAH+ vehicle group(F=9.560, P=0.011). The water content of the SAH+ Panobinostat group was lower than that of the SAH+ vehicle group(F=8.211, P=0.020). The correlation analysis indicated that the level of acetylation of H3 was negatively correlated with the neurological score(r=-0.585, P=0.046).@*Conclusion@#Panobinostat can improve the neurological behavior and alleviate early brain injury in the SAH model.

Chidamide enhances inhibitory effect on colon cancer cells by modulating tumorassociated macrophage / 中国肿瘤生物治疗杂志

@# Objective: To investigate the effect of tumor-associated macrophage (TAM) on the anti-tumor function of chidamide and to explore the mechanism. Methods: Mouse macrophage cell linesAna1 and Raw264.7 were cultured in vitro and induced into TAM with tumor supernatant. HDAC enzyme activity was detected after TAM treated with chidamide. The mRNA expressions of cytokines, such as IL-6, IL-12,TNF and IL-1β, in TAM were detected by qPCR. The protein expression of NF-κB and STAT3 in TAM treated with chidamide were detected by Wb. The mixture of TAM and colon cancer CT26 cells was inoculated into nude mice to construct the subcutaneous xenograft model; and the efficacy of chidamide (3.87 mg/kg) on the growth of CT26 xenograft tumors was observed. The protein expressions of PCNA, F4/80, Arg1 and iNos were detected by immunohistochemistry. Results: Chidamide inhibited the proliferation of CT26 cells. In the in vivo experiment, the inhibition rate of chidamide alone on CT26 xenograft was about 18.7%; however, the inhibition rate was up to 57.2% with the presence of TAM. Chidamide could inhibit the activity of HDAC enzyme in TAM, and further increase the Histone acetylation level. Chidamide could affect the expression of nuclear transcription factor NF-κB, inhibit the expressions of Arg1, IL-6 and IL-12, but up-regulate the expressions of iNOS, TNF and IL-1β in TAM. Conclusion: Chidamide can enhance its inhibitory effect on colon cancer CT26 cells via regulating the expression of cytokines and inhibiting the activity of HDAC in TAM.