Branched Chain Amino Acids Promote ATP Production Via Translocation of Glucose Transporters

PurposeWe have previously shown that maintenance of ATP levels is a promising strategy for preventing neuronal cell death, and that branched chain amino acids (BCAAs) enhanced cellular ATP levels in cultured cells and antagonized cell death. BCAAs attenuated photoreceptor degeneration and retinal ganglion cell death in rodent models of retinal degeneration or glaucoma. This study aimed to elucidate the mechanisms through which BCAAs enhance ATP production.MethodsIntracellular ATP concentration was measured in HeLa cells under glycolysis and citric acid cycle inhibited conditions. Next, glucose uptake was quantified in HeLa cells and in 661W retinal photoreceptor-derived cells under glycolysis inhibition, endoplasmic reticulum stress, and glucose transporters (GLUTs) inhibited conditions, by measuring the fluorescence of fluorescently labeled deoxy-glucose analog using flow cytometry. Then, the intracellular behavior of GLUT1 and GLUT3 were observed in HeLa or 661W cells transfected with enhanced green fluorescent protein-GLUTs.ResultsBCAAs recovered intracellular ATP levels during glycolysis inhibition and during citric acid cycle inhibition. BCAAs significantly increased glucose uptake and recovered decreased glucose uptake induced by endoplasmic reticulum stress or glycolysis inhibition. However, BCAAs were unable to increase intracellular ATP levels or glucose uptake when GLUTs were inhibited. Fluorescence microscopy revealed that supplementation of BCAAs enhanced the translocation of GLUTs proteins to the plasma membrane over time.ConclusionsBCAAs increase ATP production by promoting glucose uptake through promotion of glucose transporters translocation to the plasma membrane. These results may help expand the clinical application of BCAAs in retinal neurodegenerative diseases, such as glaucoma and retinal degeneration.     

Hyperlipidemia as a risk factor for Trousseau syndrome-related cerebral infarction in patients with advanced gastrointestinal cancer

Trousseau syndrome-related cerebral infarction rarely occurs during chemotherapy in patients with gastrointestinal (GI) cancer, and its clinical features remain unclear. The present study aimed to examine the clinical features of Trousseau syndrome-related cerebral infarction developed during chemotherapy for GI cancer. The present retrospective cohort study consecutively enrolled 878 patients with unresectable GI cancer who received chemotherapy at the Multidisciplinary Treatment Cancer Center, Kurume University Hospital (Kurume, Japan) between April 2014 and March 2020. Patients with colorectal cancer (n=308) were the most common, followed by those with pancreatic (n=242), gastric (n=222) and biliary tract (n=59) cancer, neuroendocrine tumors (n=34) and duodenal cancer (n=11). Among the 878 patients, Trousseau syndrome-related cerebral infarction occurred in 8 (0.9%) patients with a median age of 70.5 years (range, 58–75 years), and 50% of the patients were male (4/8). In total, 3 patients had gastric cancer, 3 had pancreatic cancer and 2 had biliary tract cancer. A greater percentage of patients with Trousseau syndrome-related cerebral infarction had hyperlipidemia (38.0%) than those without (8.2%; P=0.005). Hyperlipidemia was a risk factor for occurrence of Trousseau syndrome-related cerebral infarction with an odds ratio of 7.009 (95% confidence interval, 1.785-27.513). Trousseau syndrome-related cerebral infarction developed during GI chemotherapy was rare and hyperlipidemia may predict its onset.     

Phencyclidine-induced head-twitch response in rats treated chronically with methysergide

This study was designed to assess whether phencyclidine (PCP)-induced behaviors in rats were potentiated after two days' withdrawal from chronic methysergide (a 5-HT2 receptor blocker) treatment (10 mg/kg per day i.p. for 12 days), in order to confirm the involvement of 5-hydroxytryptamine (5-HT) neurons in PCP actions. The PCP (10 mg/kg)-induced behaviors (head-twitch, head-weaving, turning and backpedalling) were attenuated by successive pretreatment with PCP (10 mg/kg per day i.p. for 12 days), while PCP- and 5-methoxy-N,N-dimethyltryptamine (2 mg/kg)-induced head-twitch increased significantly after the repeated methysergide treatment was stopped. The development of tolerance to PCP-induced head-twitch was antagonized by pretreatment with methysergide. Furthermore, Scatchard plots of specific [3H]ketanserin binding at the 5-HT2 receptors and [3H]PCP binding at the PCP receptors in the methysergide group revealed significant increases in binding capacity (Bmax) with no change in affinity (Kd). On the contrary, after development of tolerance to PCP, there were significant decreases in Bmax of [3H]ketanserin binding with no change in affinity. PCP can thus displace [3H]ketanserin at the 5-HT2 receptor site, but not [3H]5-HT at the 5-HT1 receptor site. These facts indicate that PCP may produce head-twitch via an agonistic interaction with 5-HT2 receptor sites.     

Arachidonate-enriched triglyceride oil does not promote tumor development in a rat medium-term multi-organ carcinogenesis model

The modifying potential on tumor development of arachidonate-enriched triglyceride oil (ARA-oil) containing approximately 40% arachidonic acid was investigated in a medium-term multi-organ carcinogenesis bioassay using male and female F344 rats. The animals were sequentially given five carcinogens with different target sites in the first 4 weeks, and then administered ARA-oil for 24 weeks at dietary levels of 0% (control), 1.25%, 2.5% or 5.0%. No statistically significant differences in incidences and multiplicities of hyperplastic and neoplastic lesions were showed in the large intestine in either sex. In the liver, kidney, and lung in both sexes, and the mammary gland and uterus in females, tumor promoting potential was not evident with ARA-oil treatment. ARA-oil did not affect the quantitative data for glutathione S-transferase placental form positive foci of the liver. Increased induction of hyperplastic or neoplastic lesions in the urinary bladder and thyroid in ARA-oil-treated groups was without dose dependence. In addition, a second experiment with ARA-oil only administration for 8-week revealed no effects on cellular proliferation in the urinary bladder or thyroid in either sex. These results indicate that ARA-oil has no tumor promoting potential in any organs or tissues initiated with the five carcinogens applied in the present study.     

Induction effect of Epstein-Barr virus specific antigens and viral production by intercellular communication

The induction of Epstein-Barr virus (EBV) determined antigens and virus production were observed when the EBV-non producer but genome positive cell line, A2L/AH or AdL, was cocultivated with the fibroblast dominant cells, NPC-fib derived from the primary culture of nasopharyngeal tissues. Such effect was not found when the EBV-genome positive cells were treated with cell free culture medium prepared from the supernatants of cocultivation or cultured medium of NPC-fib cells. It was considered to indicate that intercellular communication influenced the reactivation of EBV genome and promoted the cells for viral productive cycle. The cytoplasmic substances of fibroblastoid cells entered to the cytoplasm of EBV-non producer but genome positive cells, passing through the cell-to-cell membrane channels mediated by intercellular communication, and some of the transferred substances might have promoted EBV production.     

Enhancement of malignant properties of human osteosarcoma cells with disialyl gangliosides GD2/GD3

The expression and implications of gangliosides in human osteosarcomas have not been systematically analyzed. In this study, we showed that gangliosides GD3 and GD2 are highly expressed in the majority of human osteosarcoma cell lines derived from oral cavity regions. Introduction of GD3 synthase cDNA into a GD3/GD2-negative (GD3/GD2-) human osteosarcoma subline resulted in the establishment of GD3/GD2+ transfectant cells. They showed increased cell migration and invasion activities in wound healing and Boyden chamber invasion assays, respectively, compared to the control cells. When treated with serum, GD3/GD2+ cells showed stronger tyrosine phosphorylation of p130Cas, focal adhesion kinase, and paxillin than GD3/GD2- cells. In particular, paxillin underwent much stronger phosphorylation, suggesting its role in cell motility. Furthermore, we tried to dissect the roles of GD3 and GD2 in the malignant properties of the transfectant cells by establishing single ganglioside-expressing cells, that is, either GD3 or GD2. Although GD3/GD2+ cells showed the most malignant properties, GD2+ cells showed almost equivalent levels to GD3/GD2+ cells in invasion and migration activities, and in the intensities of tyrosine phosphorylation of paxillin. Among Src family kinases, Lyn was expressed predominantly, and was involved in the invasion and motility of GD3- and/or GD2-expressing transfectants. Furthermore, it was elucidated by gene silencing that Lyn was located in a different pathway from that of FAK to eventually lead paxillin activation. These results suggested that GD2/GD3 are responsible for the enhancement of the malignant features of osteosarcomas, and might be candidate targets in molecular-targeted therapy.     

Circulatory disturbances during the first postnatal 24 hours in extremely premature infants 25 weeks or less of gestation with histological fetal inflammation

AIM: To investigate the effect of pre-existing fetal inflammation on hemodynamics during the first postnatal 24 h in extremely premature infants or= 3 than infants with no fetal inflammation (49% vs 17%) (P=0.04). Infants with fetal inflammation had significantly higher heart rate (P=0.005), catecholamine index (P=0.019) and volume load (P=0.021). CONCLUSION: Histological evidence of fetal inflammation in extremely premature infants is associated with circulatory disturbances over the first 24 h of life and increases in the incidence of IVH >or= 3.     

GRADE guidelines: 13. Preparing Summary of Findings tables and evidence profiles—continuous outcomes

Presenting continuous outcomes in Summary of Findings tables presents particular challenges to interpretation. When each study uses the same outcome measure, and the units of that measure are intuitively interpretable (e.g., duration of hospitalization, duration of symptoms), presenting differences in means is usually desirable. When the natural units of the outcome measure are not easily interpretable, choosing a threshold to create a binary outcome and presenting relative and absolute effects become a more attractive alternative.When studies use different measures of the same construct, calculating summary measures requires converting to the same units of measurement for each study. The longest standing and most widely used approach is to divide the difference in means in each study by its standard deviation and present pooled results in standard deviation units (standardized mean difference). Disadvantages of this approach include vulnerability to varying degrees of heterogeneity in the underlying populations and difficulties in interpretation. Alternatives include presenting results in the units of the most popular or interpretable measure, converting to dichotomous measures and presenting relative and absolute effects, presenting the ratio of the means of intervention and control groups, and presenting the results in minimally important difference units. We outline the merits and limitations of each alternative and provide guidance for meta-analysts and guideline developers.