Intragastric Gavage Research Articles

Long-term exposure to lead reduces antioxidant capacity and triggers motor neurons degeneration and demyelination in spinal cord of adult rats.

Lead is a toxic metal found in environment with great neurotoxic potential. The main effect is associated with impairments in hippocampus and cerebellum, driving to cognitive and motor dysfunctions, however, there is a lack of evidences about the effects over the spinal cord. In this way, we aimed to investigate in vivo the effects of long-term exposure to lead acetate in oxidative biochemistry and morphology of rats' spinal cord. For this, 36 male Wistar rats (Rattus norvegicus) were divided into the group exposed to 50mg/kg of lead acetate and control group, which received only distilled water, both groups through intragastric gavage, for 55 days. After the exposure period, the animals were euthanized and the spinal cords were collected to perform the analyses of lead levels quantification, oxidative biochemistry evaluation by levels of malondialdehyde (MDA), nitrites and the antioxidant capacity against peroxyl radicals (ACAP). Besides, morphological evaluation with quantitative analysis of mature and motor neurons and reactivity to myelin basic protein (MBP). Our results showed high levels of lead in spinal cord after long-term exposure; there was a reduction on ACAP level; however, there was no difference observed in MDA and nitrite levels. Moreover, there was a reduction of mature and motor neurons in all three regions, and a reduction of immunolabeling of MBP in the thoracic and lumbar segments. Therefore, we conclude that long-term exposure to lead is able of increasing the levels of the metal in spinal cord, affecting the antioxidant capacity and inducing morphological impairments in spinal cord parenchyma. Our results also suggest that the tissue impairments triggered by lead may be resultant from others molecular mechanisms besides the oxidative stress.

Pulsatilla Decoction Can Treat the Dampness-Heat Diarrhea Rat Model by Regulating Glycerinphospholipid Metabolism Based Lipidomics Approach.

Ethnopharmacological RelevanceDiarrhea is a major medical problem in clinical practice. According to the theory of traditional Chinese medicine (TCM), different types of diarrhea should be treated with different TCM formulations based on the targeted medical condition. Dampness-heat diarrhea (DHD) is a serious diarrheal disease and Pulsatilla decoction (PD), a TCM, has been found effective against DHD.ObjectiveThe aim of this study was to clarify the mechanism of action of PD in DHD using an untargeted lipidomics strategy.Materials and MethodsWistar rats were randomized to four groups, including the control group, model group, PD groups and self-healing group. The PD groups were given a daily intragastric gavage of PD at doses of 3.76 g/kg. The rat model of DHD established by such complex factors as high-sugar and high-fat diet, improper diet, high temperature and humidity environment, drinking and intraperitoneal injection of Escherichia coli., which imitated the inducing conditions of DHD. Then the clinical symptoms and signs, blood routine, serum inflammatory cytokines levels and the histopathological changes of main organs were detected and observed to evaluate DHD model and therapeutic effect of PD. Lipid biomarkers of DHD were selected by comparing the control and model groups with the colon lipidomics technology and an ultra-high performance liquid chromatography (UHPLC) coupled with Q Exactive plus mass analyzer. Multivariate statistical analysis and pattern recognition were employed to examine different lipids within the colon of PD-treated rats.ResultsThe clinical symptoms and signs of the model rats were consistent with the diagnostic criteria of DHD. After treatment with PD, the clinical symptoms and signs of the rats with DHD were improved; the indexes of blood routine and inflammatory cytokines levels tended to be normal. The lipidomics profile of the model group were evidently disordered when compared to the control group. A total of 42 significantly altered lipids between the model-control groups were identified by multivariate statistical analysis. DHD may result from such lipid disorders which are related to glycerophospholipid metabolism, arachidonic acid (AA) metabolism, and sphingolipid metabolism. After PD treatment, the lipidomic profiles of the disorders tended to recover when compared to the model group. Twenty lipid molecules were identified and some glycerophospholipids and AA levels returned close to the normal level.ConclusionGlycerophospholipid metabolism may play an important role in the treatment of dampness-heat induced diarrhea using PD.

Chaiqin chengqi decoction alleviates severe acute pancreatitis associated acute kidney injury by inhibiting endoplasmic reticulum stress and subsequent apoptosis

BackgroundAcute kidney injury (AKI), characterized by an increase of serum creatinine and urea, is a severe complication of severe acute pancreatitis (SAP) with high mortality. Endoplasmic reticulum (ER) stress has been considered as a key pathologic process in AKI. Chaiqin chengqi decoction (CQCQD) is an effective Chinese medicine formula for SAP treatment in China and has been used for many years. Our goal is to explore the role of CQCQD on ER stress of AKI in experimental SAP. Materials & methodsSAP was induced in rats by retrograde duct injection of 5% sodium taurocholate (NaTC, 1 ml/kg), sham operation (SO) rats simultaneously received saline infusion. Intraperitoneal injection of 4-PBA (50 mg/kg, once a day for three days before the surgery) or intragastric gavage of CQCQD (1 g/kg, 2 hourly × 3 after disease induction) was used to treat SAP rats. All animals were humanely sacrificed 12 h after disease induction. Histopathology scores of kidney and pancreas; serum biochemical indices and kidney protein levels of ER stress and apoptosis markers were assessed. Tubular epithelial cell line (HK-2) was treated either with TNF-α (10 ng/ml) or IL-6 (10 ng/ml) for 12 h plus either 4-PBA (0.1 M) or CQCQD (1 mg/ml) for in vitro study. Cell viability and markers of ER stress and apoptosis were measured. ResultsDuctal perfusion of NaTC caused significant increases in serum lipase, amylase and pancreatic histopathology (inflammatory cell infiltration, interstitial edema, and acinar cell necrosis). Kidney histopathology (tubular dilation, brush border loss, little tubular necrosis, and cast formation), serum creatine and urea levels were raised when compared with the SO group. Moreover, apoptotic cell death markers (caspase-9, cleaved-caspase-3, and TUNEL) and kidney ER stress proteins (BIP, IRE1-α, XBP1s, and CHOP) were elevated after NaTC administration. 4-PBA and CQCQD significantly alleviated histopathological changes of kidney and pancreas, inflammatory cytokines, biochemical markers of AKI, ER stress proteins and apoptotic cell death markers. They also protected HK-2 cells from injury of TNF-α and IL-6, and alleviated both ER stress and apoptosis proteins in vitro. ConclusionCQCQD may alleviate SAP-related AKI by inhibiting ER stress-related apoptosis.

Intermittent Ethanol Access Increases Sensitivity to Social Defeat Stress

Comorbidity between alcoholism and depression is extremely common. Recent evidence supports a relationship between alcohol exposure and stress sensitivity, an underlying factor in the development of depression. Our laboratory has recently shown that chronic alcohol gavage increases sensitivity to social defeat stress (SDS). However, the effects of voluntary alcohol consumption, resulting from protocols such as intermittent ethanol access (IEA), on defeat stress sensitivity have yet to be elucidated. We first assessed the effects of 4weeks of IEA to 20% alcohol on sensitivity to subthreshold SDS exposure. Next, to examine neuroinflammatory mechanisms, we analyzed gene expression of inhibitor of NFkB (IkB) following IEA or chronic alcohol exposure (10days of 3.0g/kg alcohol via intragastric gavage). Then, we quantified NFkB activation via β-galactosidase immunohistochemistry following IEA or chronic alcohol gavage in NFkB-LacZ mice. IEA-exposed mice displayed an increase in sensitivity to subthreshold SDS compared to water-drinking controls. We also found that IkB gene expression was decreased in the nucleus accumbens (NAC) and amygdala (AMY) following IEA but was not altered following chronic alcohol gavage. Finally, we observed increased NFkB activity in the central amygdala (CEA), basolateral amygdala (BLA), and medial amygdala (MEA) after IEA, and increased NFkB activity solely in the CEA following chronic alcohol gavage. These findings further corroborate that prior alcohol exposure, in this case intermittent voluntary consumption, can impact development of depressive-like behavior by altering stress sensitivity. Furthermore, our results suggest the CEA as a potential mediator of alcohol's effects on stress sensitivity, as NFkB was activated in this region following both IEA and chronic alcohol gavage. Thus, this study provides novel insight on alterations in the NFkB pathway and identifies specific regions to target in future experiments assessing the functional role of NFkB in these processes.

Preventive and Therapeutic Effects of Astaxanthin on Depressive-Like Behaviors in High-Fat Diet and Streptozotocin-Treated Rats.

The comorbidity of diabetes and depression has a negative impact on both lifestyle and quality of life. Astaxanthin (AST) has been demonstrated to improve glucose metabolism and has antidepressant-like effects, but it is not clear whether AST has potential for preventing depression in diabetes. The aim of this study is to observe the preventive and therapeutic effects of AST on glucose metabolism or depressive-like behaviors in a diabetic rat model produced by feeding with a high-fat diet for 10 weeks followed by injection of 25 mg/kg streptozotocin (STZ). Preventive treatment with AST at doses of 7.5, 15, and 25 mg/kg/day was given by intragastric gavage 4 weeks before STZ injection. Preventive plus therapeutic treatment also involved therapeutic AST treatments for 6 more weeks after STZ injection, whereas therapeutic-only treatment involved only the 6-week post-STZ treatment. Depressive-like behaviors were evaluated at the end of the treatment by using open field, locomotor activity, elevated plus maze, and forced swimming tests. Preventive and therapeutic treatment with AST both reduced the level of fasting glucose, improved glucose tolerance, and decreased total TCh and TG in diabetic rats. Preventive or preventative plus therapeutic treatment with AST decreased the immobility time and increased the time spent in the open arms of an elevated plus maze and locomotor activity in diabetic rats. However, therapeutic treatment with AST alone failed to affect the depressive-like behaviors. Preventive or preventative plus therapeutic treatment with AST at doses of 15 or 25 mg/kg significantly increased the expression of pERK, pAKT, pCREB, and BDNF in the prefrontal cortex (PFC) in diabetic rats. In contrast, therapeutic treatment with 25 mg/kg AST alone increased the expression of pERK in the PFC. This study indicates that AST may be used as a preventive or therapeutic approach for co-morbidity of diabetes and depression.

Protective effects of thymoquinone and diallyl sulphide against malathion-induced toxicity in rats.

Malathion is a potent organophosphate insecticide that inhibits acetylcholinesterase (AChE) enzyme. Our experimental objective was to investigate the beneficial effects of diallyl sulphide (DAS) and thymoquinone (TQ) against malathion-induced oxidative stress in rat cerebral, hepatic, and renal tissues. For 30days, rats received corn oil alone (negative control) or malathion by intragastric gavage (200mg/kg daily), either alone (positive control) or combined with oral DAS (200mg/kg daily) or TQ (10mg/kg daily) (treatment groups). Later, blood samples were collected via direct cardiac puncture and tissue samples were obtained for biochemical analysis. Malathion administration was associated with significant increases (p < 0.05) in the serum levels of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, γ-glutamyl transferase, cholesterol, urea, creatinine, and 8-OHdG (DNA damage biomarker), as well as significant (p < 0.05) decreases in theserum levels of total proteins, albumin, triglycerides, and AChE. Moreover, it significantly increased thetissue concentrations of malondialdehyde and nitric oxide and reduced tissue glutathione concentration and activities of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase). Treatment of malathion-intoxicated rats with DAS or TQ significantly minimized these biochemical and oxidative effects with more frequent reversal to normal ranges of serum biomarkers, tissue oxidative markers, and antioxidant enzymes in the TQ group. In conclusion, treatment with DAS or TQ ameliorated the biochemical and oxidative effects of malathion, probably through reducing the generation of reactive oxygen and nitrogen radicals, as well as enhancing the antioxidant defense mechanisms.

Effects of ethanol on plasma ghrelin levels in the rat during early and late adolescence.

Ghrelin is an appetite-regulating peptide that is primarily secreted by endocrine cells in the stomach and is implicated in regulation of alcohol consumption and alcohol-reinforced behaviors. In the present study, adolescent Sprague-Dawley rats received intermittent ethanol (AIE) exposure by intragastric intubation (5g/kg) or vapor inhalation, manipulations conducted between postnatal days (PD) 28-43. On the first and last day of AIE exposure, the level of intoxication was examined 1h after ethanol gavage or upon removal from the vapor chamber. This was immediately followed by a blood draw for determination of the blood ethanol concentration (BEC) and plasma levels of acylated ghrelin (acyl-ghrelin; active). On PD29, plasma levels of acyl-ghrelin were significantly elevated in male (but not female) rats in response to acute ethanol exposure by both gastric gavage and vapor inhalation. Importantly, assessment of plasma acyl-ghrelin in response to repeated ethanol exposure revealed a complex interaction of both sex and method of AIE exposure. On PD43, vapor inhalation increased plasma acyl-ghrelin in both males and females compared to their air-control counterparts, whereas there was no change in plasma levels of acyl-ghrelin in either male or female rats in response to exposure by intragastric gavage. Assessment of plasma acyl-ghrelin following a 30-day ethanol-free period revealed AIE exposure did not produce a change in basal levels. In addition, an acute ethanol challenge in adult rats of 5g/kg via gastric gavage had no effect on plasma ghrelin levels when assessed 1h after initiation of exposure. Collectively, these observations suggest that acyl-ghrelin, a primary gut-brain signaling hormone, is elevated by ethanol during early adolescence independent of administration route, and in gender-dependent fashion.

Activity of robusta coffee on the expression of CRP and MMP-9 against hyperlipidemia

Hyperlipidemia especially LDL accumulation causing inflammation in blood vessel. CRP and MMP-9 are component that triggering in inflammation process. This study to know activity of robusta coffee against hyperlipidemia on this component. This study using male wistar rats were divided into three groups ; normal, hyperlipidemia and that were given coffee with high fat diet groups. Robusta coffee was given 3.6x10-6 m3 by intragastric gavage. Bloodcollection was carried out using infra-orbital for analysis of LDL levels. Furthermore, the experimental animals were sacrificed and coronary arteries were taken for CRP and MMP-9 immunohistochemical staining. Data were analyzed using ANOVA followed LSD test. Results show The highest expression score for CRP and MMP-9 within the hyperlipidemia group was 188.27 ± 1.8 and 277.56 ± 2.1. The decrease in the expression score of CRP and MMP-9 happened within the ones that were given coffee with 59.33 ± 1.5 and 116.7 ± 0.2 each. Results showed that were differences in the expression of CRP andMMP-9 in all groups (p <0.05). In conclusion, activity robusta coffee can decreases the expression of CRP and MMP-9 against hyperlipidemia. Key words: Coronary disease; hyperlipidemia; robusta coffee.

Effects of Moringa oleifera L. Extract on leydig and sertoli cells induced high Temperature on Rattus norvegicus

The aim of this study was to investigate the protective effect of Moringa oleifera leaves extract on the number of leydig and sertoli cells on Rattus norvegicus due to induced high temperature. Twenty five male rat were divided into five groups, five rat for each group and administered through intragastric gavage with differents treatments for 21 days. The treatment groups were C–(NaCMC 1% 1ml), C+ (NaCMC 1% 1ml + high temperature induction), T1, T2, and T3 (100, 200, and 400mg/kg bw Moringa oleifera Lam leaves ethanol extract respectively+high temperature induction). The high temperature induction was 40°C for one hour. The observation was done by examined the histopathological changes on the numbers of Leydig and Sertoli cells. The research showed that Moringa oleifera leaves extract could protect the leydig and sertoli cells in rat testes from destructive effect of high temperature induction. Keywords: Moringa oleifera, Leydig, Sertoli, Testes

Coconut milk gavage enhanced fecal bile excretion by modulating hepatic Fxr expression but failed to improve fasting serum cholesterol profile in C57BL/6 mice

The consumption of coconut milk has long been regarded as detrimental to cardiovascular health due to its high saturated fatty acid content. Contradictorily, emerging evidences have highlighted that the fatty acids in coconut lipids, which comprise mostly of medium-chain fatty acids (MCFA), may be beneficial to the regulation of serum cholesterol. To identify the potential health effect of coconut milk on lipid metabolism, this current study employed an intragastric gavage method on C57BL/6 mice to investigate the physiological and molecular alteration in the mice subject after 8 weeks of gavage intervention. The supplementation of coconut milk did not affect the levels of serum triglyceride, but it induced the total serum cholesterol after 2 weeks of treatment. The serum cholesterol level subsequently plateaued, but an increase in bile acid excretion was observed, most likely through the modulation of bile regulating genes, i.e. farnesoid X receptor (Fxr) and Cyp7a1. Despite that, the total cholesterol to HDL cholesterol ratio of coconut milk group was comparable to that of the light cream group. In short, coconut milk supplementation promoted cholesterol excretion through the fecal bile route but did not significantly improve the serum cholesterol profile of C57BL/6 mice.

Gubenzhike Recipe Ameliorates Respiratory Mucosal Immunity in Mice with Chronic Obstructive Pulmonary Disease through Upregulation of the γδT Lymphocytes and KGF Levels.

Background Gubenzhike recipe, a traditional Chinese herbal compound, was assumed to have a possible beneficial effect on COPD. This study was designed to elucidate the mechanism from the perspective of respiratory mucosal immunity. Methods COPD model was induced by exposure to cigarette smoke and LPS instillation in mice for 12 weeks. Animals were administered solution of Gubenzhike recipe by intragastric gavage daily for 4 weeks. After that, mice were sacrificed for lung function test and histological examination of lung tissues. The levels of IL-6 and IL-13 in serum, bronchoalveolar lavage fluid (BALF), and intestinal mucus were measured by ELISA. The KGF and KGFR in lung tissue were analysed by immunohistochemical staining, ELISA, and western blotting, and the mRNA expressions were assessed by PCR. γδT lymphocytes in the lungs were isolated and analysed by immunohistochemical staining and flow cytometry. Results Gubenzhike recipe improved the structure of airway and damage of lung tissue and also the respiratory status and lung function, reduced the content of IL-6 in serum and BALF and IL-13 in BALF and intestinal mucus, increased the proportion of γδT cells in lung tissue, and promoted the secretion of KGF and KGFR (P < 0.05). Conclusion We for the first time demonstrated an experimental procedure for the isolation of γδT lymphocytes from lung tissue. This study suggested that Gubenzhike recipe could enhance the respiratory mucosal immunity which provided experimental evidence for its effects of reinforcing “wei qi” by means of strengthening vital qi, tonifying spleen and kidney, relieving cough, and reducing phlegm in TCM.

Fructo-oligosaccharides from Morinda officinalis remodeled gut microbiota and alleviated depression features in a stress rat model

BackgroundInulin-type fructo-oligosaccharides (FOSs) purified from Morinda officinalis How., an effective oral antidepressant for mild to moderate depression, have a largely unknown efficacy and poor bioavailability. PurposeTherefore, the microbiota-gut-brain axis was used to investigate the antidepressive properties of FOSs at the interface of the gut microbiota (GM). Study design and methodsFOSs was introduced via intragastric gavage to rats exposed to chronic unpredictable mild stress (CUMS), and the antidepressive effects were investigated through behavioral tests, intestinal morphology and corticosterone levels. Bacterial genomic DNA was extracted from feces, and the GM was profiled for using enterobacterial repetitive intergenic consensus (ERIC)-PCR analysis, partial least squares-discriminant analysis (PLS-DA) and 16S rRNA gene pyrosequencing. ResultsIt was observed that FOSs alleviated depression-like behaviors and repaired intestinal epithelia damages. FOSs treatment lowered corticosterone levels in the plasma and urine of the model rats. Moreover, the GM compositions of normal and model rats were distantly clustered and were mainly related to the disappearance of beneficial bacteria (e.g., Acinetobacter, Barnesiella, Coprococcus, Dialister, Lactobacillus, and Paenibacillus) and appearance of depression-associated bacteria (e.g., Anaerostipes, Oscillibacter, Proteobacteria, and Streptococcus) in depressive rats. Interestingly, the dysbiosis in depressive rats’ gut was reinstated with FOSs treatments. Notably, FOSs promoted the abundance of the bacterial phylum Cyanobacteria, a group of bacteria known for the secretion of pharmacologically important metabolites, such as H2S, that exhibit antidepressant-like properties. Apparently, FOSs-induced modulation of GM was more antidepressive compared to a component of FOSs, degrees of polymerization (DP) 5, and fluoxetine, the standard antidepressant drug. ConclusionIn conclusion, this study implied that antidepressant efficacy of FOSs was inseparable from and strongly associated with the modulation of the host’ s GM.

Mangiferin exerts neuroprotective activity against lead-induced toxicity and oxidative stress via Nrf2 pathway

ObjectiveThe study was designed to assess the beneficial role of mangiferin (MGN) in lead (Pb)-induced neurological damages in the activation of Nrf2-governed enzymes, genes and proteins. MethodsA total of 96 weaned Wistar rats (48 males and 48 females, 26- to 27-day-old), weighing 50−80 g were used. The experiment was performed in six groups: normal group (control, n = 16), model group (chronic Pb exposed, n = 16), Dimercaptosuccinic acid (DMSA)-treated group (positive control, Pb + DMSA, n = 16), three MGN-treated groups with different doses (Pb + MGN, n = 48). Normal group freely had access to purified water. DMSA-treated group was given DMSA, which was clinically used as the standard treatment for moderate Pb poisoning, at 50 mg/kg (2 mL suspension with purified water) by intragastric gavage (ig) 4 continual days a week for 4 weeks, MGN-treated groups were given MGN at 50, 100, or 200 mg/kg (2 mL suspension with purified water) by ig daily for 4 weeks. At the end of the treatment, all rats were sacrificed and the brain samples were collected. The haematoxylin and eosin (H&E) staining was used for observation of histopathology. Commercial kit, real-time quantitative polymerase chain reaction (RT-qPCR), Western-blot and immunohistochemistry (IHC) detection were used to detect the mRNA and protein expression. ResultsEight weeks exposure to Pb-containing water resulted in pathological alterations, anti-oxidative system disorder in the brain, all of which were blocked by MGN in a Nrf2-dependent manner. Nrf2 downstream enzymes such as HO-1, NQO1, γ-GCS were activated. Nrf2, GCLC, GCLM, HO-1 mRNA and total Nrf2, Nuclear Nrf2, γ-GCS, HO-1 protein expression were affected too. ConclusionMGN ameliorated morphological damage in the hippocampus. Its neuroprotective effects were achieved by the activation of the Nrf2 downstream genes. The data from this in vitro study indicates that MGN targeting Nrf2 activation is a feasible approach to reduce adverse health effects associated with Pb exposure. Thus, MGN could be an effective candidate agent for the Pb-induced oxidative stress and neurotoxicity in the human body.

The Histological and Immunohistochemical Study of Tramadol Induced Testicular Toxicity and Protective Effects of Resveratrol in Adult Male Albino Rats

Background and Objectives: Tramadol is a centrally acting analgesic drug. Chronic intake of Tramadol has negative impactson testis. Resveratrol is considered to be a natural compound that has antioxidant and anti-inflammatory effects.Aim : The present study was designed to monitor the impacts of the use of Tramadol on the testis of adult male albino rats andthe beneficial effects of Resveratrol.Materials and Methods: 40 adult male albino rats were classified randomly into 4 groups. Each one inclued10 rats as follows:Group I (control group): received 0.1 ml of physiological saline solution. Group II: received Resveratrol 20 mg/kg/day orallyfor 4 weeks. Group III: (Tramadol-treated group): received Tramadol 50 mg/kg/day orally for 4 weeks. GroupIV: receivedTramadol 50 mg/kg body weight daily orally followed byResveratrol 20 mg/kg body weight daily by intragastric gavage for 4 week. Blood samples were obtained to assess serumlevels of testosterone, FSH and LH. Testes were removed and prepared for histological examination and immunohistochemicalstaining. The experimental data were analyzed using IBM SPSS Statistics software.Results: Tramadol-treated group showed severe distortion of the testicular structure in which many seminiferous tubuleswere degenerated with losing their normal histological architecture. Meanwhile, sections of testes of group IV (Tramadol–Resveratrol treated group) showed nearly normal histology. Positive immune-reactivity for PCNA in the control, Resveratroltreated and Tramadol - Resveratrol treated groups while, Tramadol- treated group showed few positive immuno-reactivity forPCNA. Serum LH, FSH and testosterone hormones levels were significantly higher in Tramadol-Resveratrol treated group compared to Tramadol treated group.Conclusion: Intake of Tramadol induced testicular damage which can be ameliorated by administration of Resveratrol in theconcomitant with Tramadol treatment.

The role of invariant natural killer T cells in experimental xenobiotic-induced cholestatic hepatotoxicity

Inflammation, especially the release of pro-inflammatory mediators, contributes to hepatocyte injury during cholestasis. Alpha-naphthylisothiocyanate (ANIT) is widely used in rodents to mimic clinical cholestasis. Lymphocytes have been reported to exacerbate ANIT - induced hepatotoxicity. However, which cell and mechanism mediate hepatic inflammatory response and hepatocyte injury in cholestasis is still not clear. Invariant natural killer T (iNKT) cells are a unique subset of T lymphocytes which are supposed to exert immune-regulatory effect on cholestatic liver damage. In the present study, we hypothesized that iNKT cells played a role in the pathogenesis of ANIT-induced cholestatic hepatotoxicity. ANIT (50 mg/kg, intragastric gavage) was administered to male mice for 16, 48, or 72 h. We found that ANIT administration activated iNKT cells, releasing Th1 cytokine IFN-γ and Th2 cytokine IL-4. Administration of ANIT induced cholestatic liver injury, evidenced by the elevated serum ALT, AST, ALP, TBA, TG and TC levels, and significant hepatic histopathological changes. However, knockout of iNKT cell were resistant to the late development of ANIT - induced liver injury due to the reduced release of inflammatory cytokines CXCL10 and ICAM-1, as well as the down-regulation of nuclear receptor Egr1. We further revealed that the improvement of ALP in iNKT cell - deficient mice was partly associated with the up-regulation of transporter MRP2 and NTCP and bile acid metabolism enzyme CYP2B10. Collectively, these results suggested that iNKT cells aggravated ANIT-induced cholestatic liver injury by inducing inflammatory response which contributed to the understanding of the mechanisms of ANIT-induced cholestasis. More importantly, the iNKT cell regulation may promote effective measures that control cholestasis.

Kanglexin, a novel anthraquinone compound, protects against myocardial ischemic injury in mice by suppressing NLRP3 and pyroptosis.

Pyroptosis is a form of inflammatory cell death that could be driven by the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation following myocardial infarction (MI). Emerging evidence suggests the therapeutic potential for ameliorating MI-induced myocardial damages by targeting NLRP3 and pyroptosis. In this study, we investigated the myocardial protection effect of a novel anthraquinone compound (4,5-dihydroxy-7-methyl-9,10-anthraquinone-2-ethyl succinate) named Kanglexin (KLX) in vivo and in vitro. Male C57BL/6 mice were pre-treated either with KLX (20, 40 mg· kg−1per day, intragastric gavage) or vehicle for 7 consecutive days prior to ligation of coronary artery to induce permanent MI. KLX administration dose-dependently reduced myocardial infarct size and lactate dehydrogenase release and improved cardiac function as compared to vehicle-treated mice 24 h after MI. We found that MI triggered NLRP3 inflammasome activation leading to conversion of interleukin-1β (IL-1β) and IL-18 into their active mature forms in the heart, which could expand the infarct size and drive cardiac dysfunction. We also showed that MI induced pyroptosis, as evidenced by increased DNA fragmentation, mitochondrial swelling, and cell membrane rupture, as well as increased levels of pyroptosis-related proteins, including gasdermin D, N-terminal GSDMD, and cleaved caspase-1. All these detrimental alterations were prevented by KLX. In hypoxia- or lipopolysaccharide (LPS)-treated neonatal mouse ventricular cardiomyocytes, we showed that KLX (10 μM) decreased the elevated levels of terminal deoxynucleotidyl transferase dUTP nick end labeling- and propidium iodide-positive cells, and pyroptosis-related proteins. We conclude that KLX prevents MI-induced cardiac damages and cardiac dysfunction at least partly through attenuating NLRP3 and subsequent cardiomyocyte pyroptosis, and it is worthy of more rigorous investigations for its potential for alleviating ischemic heart disease.

P2867Vildagliptin reduces inducibility of atrial fibrillation in hypertensive rats complicated with diabetes mellitus

Abstract Background Atrial fibrillation (AF) is the most common arrhythmia in clinical practice, increasing the incidence of ischemic stroke. Diabetes mellitus (DM) is a predictor of stroke and thromboembolism, and it was reported to be an independent risk factor for AF. A recent study has shown that, in obese mice with diabetes, dipeptidyl peptidase-4 (DPP-4) inhibitor prevents myocardial fibrosis, active oxygen stress, weight loss and improves myocardial hypertrophy. However, the effects of DPP-4 inhibitors on atrial remodeling associated with diabetes and atrial fibrillation have not yet been clarified. Purpose This study was performed to assess whether a DPP-4 inhibitor (vildagliptin) ameliorates atrial remodeling in spontaneously hypertensive rats (SHR) with streptozotocin-induced diabetes. Methods Rats were divided into 3 groups: SHR without DM, SHR with DM treated with vehicle and SHR-DM treated with vildagliptin (3mg/kg/day; intragastric gavage). For each group, blood pressure, blood glucose level and body weight were measured serially. Cardiac function was also evaluated by echocardiography. Then, we examined AF inducibility by intracardiac electrophysiological study and the inflammation-induced atrial remodeling by biochemical analysis after 4 weeks of treatment. Results There was no significant difference in blood pressure and blood gucose level between vehicle and vildagliptin groups. Administration of vildagliptin significantly reduced AF inducibility compared with rats with vehicle. In DM rats treated with vehicle, rapid atrial pacing promoted the gene expression of inflammatory and fibrosis-related biomarkers (TNF-α, MCP-1, collagen-1) in atrium. Vildagliptin reduced these gene expression levels. In addition, administration of vildagliptin significantly reduced the interstitial fibrosis in atrium. Conclusions DPP-4 inhibitor, vildagliptin. could prevent atrial inflammation and reduce the AF inducibility in SHR complicated with DM.

Platinum Nanoparticles As A Therapeutic Agent Against Dextran Sodium Sulfate-Induced Colitis In Mice.

PurposeThis study aimed to evaluate the anti-colitis potential of platinum nanoparticles (PtNPs).Materials and methods5-, 30- and 70-nm PtNPs were administered to C57BL/6 mice once daily by intragastric gavage for 8 d during and after 5-d dextran sodium sulfate treatment.ResultsAccording to body weight change, stool blood and consistency, and colon length and histopathology, PtNPs size-dependently alleviated DSS-induced murine colitis. PtNPs enhanced gut-barrier function by upregulating the colonic expressions of heat-shock protein 25 and tight junction proteins. Based on colonic myeloperoxidase activity, colonic and peripheral levels of interleukin-6 and tumor necrosis factor-α, and peripheral counts of white blood cells, PtNPs attenuated colonic and systemic inflammation. By suppressing lipopolysaccharide-triggered production of proinflammatory mediators, including nitric oxide, tumor necrosis factor-α and interleukin-6, PtNPs exerted direct anti-inflammatory activities in RAW264.7 macrophages through a mechanism involving intracellular reactive oxygen species scavenging and Toll-like receptor 4/NF-κB signaling suppression. High-throughput 16S rRNA sequencing of fecal samples unveiled that PtNPs induced gut dysbiosis by unfavorably altering α-diversity, Firmicutes/Bacteroidetes ratio, and richness of certain specific bacteria.ConclusionPtNPs are a promising anti-colitis agent, but may negatively impact gut-microbiota.

Effect of chronic L-carnitine supplementation on carnitine levels, oxidative stress and apoptotic markers in peripheral organs of adult Wistar rats

This study investigated the effects of L-carnitine supplementation on carnitine levels, oxidative stress and apoptotic markers in the stomach, kidney, liver and testis tissues in adult rats. Rats were randomized to control and L-carnitine supplemented (LCAR) groups. Control group received distilled water for 7 months by intragastric gavage and the LCAR group was given 50 mg/kg/day L-carnitine via intragastric intubation for the same period. L-carnitine concentrations and caspase-3 activity were measured by fluorometric methods while cleaved caspase-3 was determined by Western blot analysis. Bcl-2 associated X protein (Bax) and B-cell lymphoma/leukemia-2 (Bcl-2) were quantified by enzyme immunoassay and Western blot analysis. Oxygen/nitrogen species (ROS/RNS) and total antioxidant capacity (TAC) were analyzed by colorimetric assay. Tissue L-carnitine concentrations were significantly increased in the LCAR group compared to controls. Anti-apoptotic Bcl-2 levels were significantly increased while pro-apoptotic Bax was significantly decreased in LCAR group rats compared to controls. Tissue caspase-3 was significantly alleviated in the LCAR group compared to controls. L-carnitine supplementation increased TAC and decreased ROS/RNS generation in the kidney, liver, stomach and testis tissues compared to controls. Obtained data suggests that L-carnitine supplementation can potentially be used to lessen both oxidative and apoptotic progression in peripheral organs.

Oral glutamine supplementation attenuates inflammation and oxidative stress-mediated skeletal muscle protein content degradation in immobilized rats: Role of 70 kDa heat shock protein

Skeletal muscle disuse results in myofibrillar atrophy and protein degradation, via inflammatory and oxidative stress-mediated NF-kB signaling pathway activation. Nutritional interventions, such as l-glutamine (GLN) supplementation have shown antioxidant properties and cytoprotective effects through the modulation on the 70-kDa heat shock protein (HSP70) expression. However, these GLN-mediated effects on cell signaling pathways and biochemical mechanisms that control the myofibrillar protein content degradation in muscle disuse situations are poorly known yet. This study investigated the effects of oral GLN plus l-alanine (ALA; GLN ​+ ​ALA-solution) supplementation, either in their free or dipeptide (L-alanyl-l-glutamine-DIP) form, on GLN-glutathione (GSH) axis and cytoprotection mediated by HSP70 protein expression in the slow-twitch soleus and fast-twitch gastrocnemius skeletal muscle of rats submitted to 14-days of hindlimb immobilization-induced disuse muscle atrophy. Forty-eight Wistar rats were distributed into 6 groups: hindlimb immobilized (IMOB group) and hindlimb immobilized orally supplemented with either GLN (1 g kg−1) plus ALA (0.61 g kg−1) ​(GLN ​+ ​ALA-IMOB group) or 1.49 ​g ​kg−1 of DIP (DIP-IMOB group) and; no-immobilized (CTRL) and no-immobilized supplemented GLN ​+ ​ALA and DIP baselines groups. All animals, including CTRL and IMOB rats (water), were supplemented via intragastric gavage for 14 days, concomitantly to immobilization period. Plasma and muscle GLN levels, lipid (thiobarbituric acid reactive substances-TBARS) and protein (carbonyl) peroxidation, erythrocyte concentration of reduced GSH and GSH disulfide (GSSG), plasma and muscle pro-inflammatory TNF-α levels, muscle IKKα/β-NF-kB signaling pathway and, the myofibrillar protein content (MPC) were measured. The MPC was significantly lower in IMOB rats, compared to CTRL, GLN ​+ ​ALA, and DIP animals (p ​< ​0.05). This finding was associated with reduced plasma and muscle GLN concentration, equally in IMOB animals. Conversely, both GLN ​+ ​ALA and DIP supplementation restored plasma and muscle GLN levels, which equilibrated GSH and intracellular redox status (GSSG/GSH ratio) in erythrocytes and skeletal muscle even as, increased muscle HSP70 protein expression; attenuating oxidative stress and TNF-α-mediated NF-kB pathway activation, fact that reverberated on reduction of MPC degradation in GLN ​+ ​ALA-IMOB and DIP-IMOB animals (p ​< ​0.05). In conclusion, the findings shown herein support the oral GLN ​+ ​ALA and DIP supplementations as a therapeutic and effective nutritional alternative to attenuate the deleterious effects of the skeletal muscle protein degradation induced by muscle disuse.