ObjectiveTo detect the induction of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in immunostimulated retinal pigment epithelial (RPE) cells to seek for the supplying of the arginine, a substrate for NOS; as well as the effects of produced NO on the tight junction of RPE-J cells. MethodsRat′s RPE-J cells were treated with interferon-γ(INF-γ), tumor necrosis factor-α(TNF-α) and lipopolysaccharide (LPS), and Northern and Western blotting were applied to analyze the expression of the citrulline-NO cycle enzymes and related enzymes and the effect of dexamethasone and cyclic adenosine monophosphate (camp) on the expression of iNOS. Immunocytochemistry reaction and Western blotting were used to evaluate the effect of produced NO on the tight junctions of RPE-J cells.ResultsiNOS and argininosuccinate synthetase (AS) were highly induced at both mRNA and protection levels in immunostimulated RPE cells while arginiosuccinate lyase (AL) was not induced. NO was produced by cells after stimulation with TNFα, IFNγ and LPS. The induction of iNOS mRNA and the production of NO by these immunostimulated cells was further enhanced by cAMP. NO was produced from citrulline as well as from arginine. And the produced NO impaired the tight junction of RPE-J cells, decreased the production of tight junction related protein ZO-1.ConclusionIn activated RPE-J cells, citrullinearginine recycling is important for NO production, and the produced NO weakened the function of tight junction of RPE-J cells.(Chin J Ocul Fundus Dis, 2005,21:32-36)
Objective To observe the effect of vitrectomy (PPV) combined with silicone oil filling on the stability of the tear film. Methods A total of 72 eyes of 36 patients with vitreous hemorrhage and retinal detachment were enrolled in the study with PPV combined with silicone oil filling. The operation and contralateral eyes were set up in the operation group and the control group respectively, each had 36 eyes. The tear film rupture time (BUT), the base tear secretion test or Schirmer Ⅰ test (SⅠT) and corneal fluorescein staining (CFS) were performed at 7, 30, 60, and 90 days after operation. The difference of BUT, SⅠT and CFS at different time points after the operation of the two groups were compared. Results After operation 7, 30 days, SⅠT and CFS increased, BUT staining is shortened in the surgery group, the differences were statistically significant (t=1.78, P＜0.05); after operation 60, 90 days, SⅠT, CFS, BUT were same between the surgery group and the contralateral eyes (t=12.39, P＞0.05). Conclusion PPV combined with silicone oil filling can affect the stability of the tear film, which can be recovered to the preoperative level at postoperative 60 days.
Tumor cells have unique energy metabolism phenomena, namely high glucose absorption, aerobic glycolysis and high lactic acid production, which are characterized by down-regulation of related proteins involved in oxidative metabolism in tumor cells, and up-regulation of glucose transporters and monocarboxylate transporters. Studies have shown that drugs that target tumor cell glucose metabolism have the ability to selectively kill tumor cells, bringing new hope for tumor treatment. Tumor stem cells are considered to be the root cause of tumor recurrence, metastasis and poor prognosis, and their energy metabolism characteristics have not yet been agreed. Studies have shown that reversing the energy metabolism of tumor stem cells can increase their chemosensitivity. This article reviews recent studies on tumor and tumor stem cell glucose metabolism and the opportunities and challenges of tumor treatment through targeting glucose metabolism, which might provide new ideas and opportunities for clinical tumor therapy.
Amine oxidase copper-containing 1 (AOC1) is a key member of copper amine oxidase family, which is responsible for deamination oxidation of histamine and putrescine. In recent years, AOC1 has been reported to be associated with various cancers, with its expression levels significantly elevated in certain cancer cells, suggesting its potential role in cancer progression. However, its function in lipid metabolism still remains unclear. Through genetic analysis, we have discovered a potential relationship between AOC1 and lipid metabolism. To further investigate, we generated Aoc1−/− mice and characterized their metabolic phenotypes on both chow diet and high-fat diet (HFD) feeding conditions. On HFD feeding conditions, Aoc1−/− mice exhibited significantly higher fat mass and impaired glucose sensitivity, and lipid accumulation in white adipose tissue and liver was also increased. This study uncovers the potential role of AOC1 in lipid metabolism and its implications in metabolic disorders such as obesity and type 2 diabetes, providing new targets and research directions for treating metabolic diseases.
ObjectiveTo summarize the remodeling of cholesterol metabolism in the occurrence and progression of pancreatic ductal adenocarcinoma (PDAC), and to review the research progress on targeted cholesterol metabolism in the treatment of PDAC. MethodRelevant literatures on cholesterol metabolism in the occurrence, development, and diagnosis and treatment of PDAC in recent years were searched and reviewed. ResultsMetabolites of PDAC tumor cells affected the expression of oncogenes or tumor suppressor genes. Signaling regulation within tumor cells affects cholesterol metabolism, characterized by increased de novo cholesterol synthesis and esterification, and reduced efflux. Tumor cells also regulated tumor immune microenvironment or tumor stroma formation through cholesterol metabolism. Inhibiting cholesterol metabolism could suppress the proliferation, invasion and migration of PDAC tumor cells, and combination therapy targeting cholesterol metabolism had a synergistic anti-PDAC effect. ConclusionsRemodeling of cholesterol metabolism occurs in both PDAC tumor cells and the tumor microenvironment, and is closely related to the occurrence, development, invasion, metastasis, and treatment response of PDAC. Targeting cholesterol metabolism or combined application with chemotherapy drugs can have anticancer effects. However, more research is needed to support the translation of cholesterol metabolism regulation into clinical treatment applications.
Objective To observe the characteristics of fundus autofluorescence （AF） distribution at the posterior pole in normal subjects. Methods Seventy-nine normal subjects （156 eyes）were studied. Confocal scanning laser ophthalmoscope (cSLO) HRA2 was used to obtain the AF average image at the posterior pole. The distance was calibrated by Digimizer image analysis system. With umbo as the center, the macula was divided into foveola, fovea, parafovea and perifovea areas which with the radius 175, 750, 1250 and 2750 mu;m respectively. Each area was further divided into inferior, superior, temporal and nasal quadrants by two radial lines angle of 90deg;, except for foveola. The AF intensity in four quadrants of different macular regions and optic disc were measured. The AF intensity in vertical and horizontal direction of umbo was also measured. Then the effects of age, eyes, and gender on AF intensity in four quadrants of different macular regions were analyzed. Results There were statistically significant differences in AF intensity among optic disc and four quadrants of macular regions （F=528.648, P＜0.05）. AF distribution was V-type in vertical direction and M-type in horizontal direction. There were statistically significant differences between age groups in foveola, inferior parafovea, temporal parafovea, inferior perifovea, superior perifovea and temporal perifovea （P＜0.01）. There were no statistically significant differences between the two eyes （P＞0.05）. Between genders group, there were statistically significant differences in foveola, superior fovea, inferior fovea, nasal fovea and temporal perifovea （P＜0.05）; no statistically significant differences in the other quadrants （P＞0.05）. Conclusions The distribution of AF intensity is inhomogeneous in macular regions and four quadrants of each region in normal subjects. AF intensity increases with aging. AF distribution is symmetrical in both eyes. There is probably no correlation between gender and AF intensity distribution.
Objective To summarize the latest research progress of tumor energy metabolism regulated by long non-coding RNA (lncRNA). Method Literatures about the recent studies on the bioenergetic metabolic mechanisms regulated by lncRNA in tumor cells were reviewed according to the results searched from PubMed database, Springer database, HighWire database, and so on. Results Aerobic glycolysis (Warburg effect) was regarded as the most important characteristics of energy metabolism in tumor cells. lncRNA could regulate many key progressions involved energy metabolism in tumor cells, such as glucose metabolism, lipid metabolism, and glutamine metabolism, resulting in accelerated uptake of glucose, decomposition of glutamine, and formation of lipid. Conclusions The functions and mechanisms of energy metabolism in tumor cells regulated by lncRNA are entirely unclear. The role of lncRNA played in cancer needs to be understood, which may contribute to new tumor biomarker detection and effective treatment strategies.
Objective To study the effect of perioperative nutritional support on protein metabolism and immunity in patients underwent liver transplantation. Methods A total of 80 patients who underwent liver transplantation in our hospital from March 2015 to March 2016 were collected retrospectively, and then the 80 patients were divided into control group (n=40) and observation group (n=40) according to the type of perioperative nutritional support. Patients of control group didn’t receive preoperatively nutritional support, and received total parenteral nutrition support before postoperative exhaust, then received enteral nutrition support after anal exhaust. Patients of observation group receive preoperatively nutritional support before surgery, and received parenteral nutrition and enteral nutrition support before postoperative exhaust. The several parameters about nutritional status and immune function were observed on 7 days and 14 days after liver transplantation, and comparison of the 2 group in these parameters was performed. Results On the protein metabolism, the levels of serum transferrin, prealbumin, and nitrogen balance on 14 days after liver transplantation were higher than those of other time points (before liver transplantation and 7 days after liver transplantation),P<0.05, both in control group and observation group. There was no significant difference in the levels of serum transferrin, prealbumin, and value of nitrogen balance between the 2 groups before liver transplantation (P>0.05). But on 7 days and 14 days after liver transplantation, the levels of serum transferrin, prealbumin, and value of nitrogen balance of the observation group were higher than those of control group (P<0.05). On the immunity, the total number of lymphocytes, value of IgG and CD4/CD8 on 14 days after liver transplantation, were superior to other time points (before liver transplantation and 7 days after liver transplantation),P<0.05, both in control group and observation group. There was no significant difference in the total number of lymphocytes, value of IgG and CD4/CD8 between the 2 groups before liver transplantation (P>0.05). But on 7 days and 14 days after liver transplantation, the levels of the total number of lymphocytes, value of IgG and CD4/CD8 in the observation group were superior to those of control group (P<0.05). Conclusion Perioperative nutritional support can improve the nutritional status and immune function in patients underwent liver transplantation.
Objective To investigate the mRNA expression of ciliary neurotrophic factor on the retina during injury and repair of optic nerves in rats. Methods Thirty-five healthy SD rats were randomly divided into 3 groups: 5 in the control group, 15 in the simply transected optic nerve group and 15 in the optic nerve-sciatic nerve anastomosis group. The simply transected and optic nerve-sciatic nerve anastomosed models were set up, and the retinal tissues of all of the rats were taken out after 3, 7 and 14 days, respectively; and the mRNA expression of CNTF in the 3 groups were observed by semiquantitative reversal transcription-polymerase chain reaction method. Results A minimum expression of CNTF mRNA was found in the retinae of the control group, and the increased rates of expression were found in the retinae of the simple transection of optic nerve group with the increase rate of 100%, 594%, and 485% on the 3rd, 7th, and 14th day respectively after the operation, while in optic nerve-sciatic nerve anastomosis group, the increase rates were found to be 258%, 752% and 515% on the 3rd, 7th, and 14th day respectively after the operation. Conclusion Retinal neurons can respond to axonal reaction of retinal ganglion cells by up-regulate endogenous CNTF after the injury of the optic nerves, which may provide a theoretic base for the application of the exogenous CNTF. (Chin J Ocul Fundus Dis，2004，20：355-357)
To investigate prospectively the short-term effect of different fat emulsions on plasma lipids and lipoproteins and to clarify the underlying mechanisms. Fifty six surgical patients were randomized to received intravenously either a 10%. Intralipid, a 20% Intralipid or no fat emulsions for 5 days postoperatively as part of a standard parenteral nutrition regimen. Serum lipids and lipoproteins were measured prior to and after the 5-day infusion period. Results: Intravenous administration of 10% Intralipid caused a marked increase of total cholesterol (Tcho), free cholesterol (Fcho), Low-density lipoprotein cholesterol (LDL-ch), phospholipid and lipoprotein X (LPX). Quantification of LPX revealed that its increase was proportionate to that of phospholipid and Tcho. Conclusion: Exogenous phospholipids when using fat emulsions with a high phospholipid/triglyceride (PL/TG) ratio play an impressive role in the formation of LPX and consequently are capable of inducing hypercholesterolemia after only a few days. Therefore, 20% Intralipid should be preferred to the corresponding 10% Intralipid for its low PL/TG ratio.