Combination of N-(4-hydroxyphenyl) retinamide and apigenin suppressed starvation-induced autophagy and promoted apoptosis in malignant neuroblastoma cells

Autophagy is a catabolic process for recycling of cellular contents in response to metabolic stress in malignant tumors. We explored efficacy of the synthetic retinoid N-(4-hydroxyphenyl) retinamide (4-HPR) and the isoflavonoid apigenin (APG) in the serum-starved human malignant neuroblastoma cells. Combination of 0.5 μM 4-HPR and 50 μM APG synergistically decreased cell viability in the serum-starved neuroblastoma SH-SY5Y, SK-N-BE2, and IMR-32 cells. Acridine orange (AO) staining and LC3 II upregulation showed that serum-starvation for 12 and 24 h progressively increased the formation of acidic vesicular organelles (AVO) and autophagy in SH-SY5Y cells. Further, AO staining and flow cytometry showed blockage of formation of AVO and accumulation of auophagic population, respectively, following the treatment of the serum-starved SH-SY5Y cells with combination of 0.5 μM 4-HPR and 50 μM APG. Combination therapy downregulated autophagy inducing proteins such as Beclin 1, LC3 II, TLR-4, and Myd88 while upregulated autophagy inhibitory p-Akt/mTOR singaling pathway. Consistent with the hypothesis that inhibition of autophagy could induce apoptosis, we noticed inhibition of autophagy and induction of apoptosis in the serum-starved SH-SY5Y cells with the suppression of the survival factor NF-κB, upregulation of pro-apoptotic Bax, downregulation of anti-apoptotic Bcl-2, activation of caspase-3, and degradation of poly(ADP-ribose) polymerase (PARP) after combination therapy. Collectively, combination of 4-HPR and APG worked synergistically to suppress autophagy and promote apoptosis in human malignant neuroblastoma cells.     

The inhibition of apoptosis by melatonin in VSC4.1 motoneurons exposed to oxidative stress,glutamate excitotoxicity,or TNF‐α toxicity involves membrane melatonin receptors

Abstract: Loss of motoneurons may underlie some of the deficits in motor function associated with the central nervous system (CNS) injuries and diseases. We tested whether melatonin, a potent antioxidant and free radical scavenger, would prevent motoneuron apoptosis following exposure to toxins and whether this neuroprotection is mediated by melatonin receptors. Exposure of VSC4.1 motoneurons to either 50 μm H₂O₂, 25 μm glutamate (LGA), or 50 ng/mL tumor necrosis factor‐alpha (TNF‐α) for 24 h caused significant increases in apoptosis, as determined by Wright staining and ApopTag assay. Analyses of mRNA and proteins showed increased expression and activities of stress kinases and cysteine proteases and loss of mitochondrial membrane potential during apoptosis. These insults also caused increases in intracellular free [Ca²⁺] and activities of calpain and caspases. Cells exposed to stress stimuli for 15 min were then treated with 200 nm melatonin. Post‐treatment of cells with melatonin attenuated production of reactive oxygen species (ROS) and phosphorylation of p38, MAPK, and JNK1, prevented cell death, and maintained whole‐cell membrane potential, indicating functional neuroprotection. Melatonin receptors (MT1 and MT2) were upregulated following treatment with melatonin. To confirm the involvement of MT1 and MT2 in providing neuroprotection, cells were post‐treated (20 min) with 10 μm luzindole (melatonin receptor antagonist). Luzindole significantly attenuated melatonin‐induced neuroprotection, suggesting that melatonin worked, at least in part, via its receptors to prevent VSC4.1 motoneuron apoptosis. Results suggest that neuroprotection rendered by melatonin to motoneurons is receptor mediated and melatonin may be an effective neuroprotective agent to attenuate motoneuron death in CNS injuries and diseases.     

Molecular evidence of apoptotic death in malignant brain tumors including glioblastoma multiforme: upregulation of calpain and caspase-3

Cell death in the core of human brain tumors is triggered by hypoxia and lack of nutrients, but the mode of cell death whether necrosis or apoptosis is not clearly defined. To identify the role of apoptosis in brain tumor cell death, we investigated macromolecular (RNA and protein) synthesis and activity in the central to peripheral region of benign [desmoplastic infantile ganglioglioma (DIG) and transitional meningioma (TMG)] and malignant [ependymoma (END), anaplastic astrocytoma (APA), and glioblastoma multiforme (GBM)] brain tumors derived from five patients who had not received previously radiotherapy or chemotherapy. Normal brain tissue (NBT) served as control. RT-PCR analysis of tumor tissues covering central to peripheral regions detected mRNA overexpression of pro-apoptotic gene bax in malignant tumors, indicating a commitment to apoptosis. The mRNA expression of calpain (a Ca(2+)-dependent cysteine protease) and calpastatin (endogenous calpain inhibitor) was altered resulting in an elevated calpain/calpastatin ratio. Calpain content and activity were increased, suggesting a role for calpain in cell death. In the mitochondria-dependent death pathway, caspase-9 and caspase-3 were also overexpressed in tumors. The increased caspase-3 activity cleaved poly(ADP-ribose) polymerase (PARP). Agarose gel electrophoresis detected a mixture of random and internucleosomal DNA fragmentation in malignant brain tumors. Overexpression of pro-apoptotic bax, upregulation of calpain and caspase-3, and occurrence of internucleosomal DNA fragmentation are now presented indicating that one mechanism of cell death in malignant brain tumors is apoptosis, and that enhancement of this process therapeutically may promote decreased tumor growth.     

Inhibitory effect of vitamin D3 on 3'methyl-4-dimethyl-amino-azobenzene-induced rat hepatocarcinogenesis: a study on antioxidant defense enzymes

The anticarcinogenic effect of vitamin D3 (VD3) on 3,-methyl-4-dimethyl-amino-azobenzene (3,-Met-DAB)-induced hepatocarcinogenesis was investigated in male Sprague-Dawley rats. Anticancer efficacy of VD3 was estimated using different possible biomarkers, namely reduced glutathione (GSH) concentration, gamma-glutamyl transpeptidase (GGT) activity, glutathione S-transferase (GST) activity, glutathione reductase (GRd) activity, glutathione peroxidase (GPx) activity in hyperplastic nodules (HNs) and non-nodular surrounding parenchyma (NNSP) liver areas. VD3 was found to control the carcinogen-induced alterations in GSH level, GST, GGT, GRd and GPx activity both in HNs and NNSP liver areas during long-term exposure. A decrease in the number of HNs was also evident in the present investigation. VD3 was proved to be an effective antitumor drug during the initiation/promotion phases of hepatic carcinogenesis but the effect was found to be less prominent during initiation and promotion phases.     

Longitudinal growth pattern of children during pre-school age and its relationship with different socio-economic classes

Summary This report deals with the study of longitudinal growth of pre-school children from different socio-economic classes in the urban community of Delhi. The role of socio-economic factors which affect the growth standards of weight, height, circumference of head, chest, arm, calf and pelvic width of these children at different ages from birth up to 5 years is discussed. It is observed that in malnutrition resulting from an adverse effect of poor socio-economic status, all measurements of the body are affected, the height and the head being the least and the weight, the circumferences of the chest, arm and calf the most. From the Longitudinal Morbidity and Mortality Survey of Children’s Unit, Indian Council of Medical Research, New Delhi.     

Paratesticular rhabdomyosarcomas and leiomyosarcomas: a clinicopathological review.

One case of embryonal paratesticular sarcoma and 2 cases of leiomyosarcomas are reported. The 13-year-old boy with embryonal sarcoma is well after an orchiectomy and high ligation of the spermatic cord followed by radiotherapy and chemotherapy. A 66-year-old man has been doing well after orchiectomy and hemiscrotectomy for a paratesticular leiomyosarcoma. The third patient had a highly pleomorphic leiomyosarcoma and died 2 months postoperatively. The clinical and histological diagnosis of paratesticular rhabdomyosarcomas and leiomyosarcomas is reviewed and the various therapeutic approaches to these neoplasms are discussed. Retroperitoneal lymph node dissection, radiotherapy and chemotherapy are important adjuncts to orchiectomy in the management of rhabdomyosarcomas. On the contrary, retroperitoneal lymph node dissection and radiotherapy are not indicated in leiomyosarcomas, since these neoplasms tend to metastasize by the hematogenous route and are radioresistant. At the present time we are unable to evaluate chemotherapy in the management of paratesticular leiomyosarcomas.     

Decrease in brain serotonin level and short term memory loss in mice: a preliminary study

Most of the information on the effects of benzene center around its hematotoxic and genotoxic effects. However, its effect on central neurotransmitters is inconclusive in terms of cognitive behavior of the host. The present results showed for the first time that chronic exposure to benzene, in drinking water, significantly inhibited serotonin (5-hydroxytryptamine (5-HT)) level in serotonergic neuron rich regions of the murine brain. This was paralleled with loss of short term memory, as evidenced by passive avoidance test, of the benzene treated animals.