Rat Spleen Tissue Research Articles

Effect of tannic acid on doxorubicin‐induced cellular stress: Expression levels of heat shock genes in rat spleen

AbstractDoxorubicin (DOX), an anthracycline group antibiotic, has been extensively employed as a potent chemotherapeutic agent for treating solid and hematopoietic tumors in humans. Amid exposure to diverse stress conditions, living organisms swiftly initiate the synthesis of heat shock proteins (HSPs), a set of highly conserved proteins. Tannic acid (TA) has garnered increasing study attention due to its special chemical properties, health benefits, and wide availability. This study's primary aim is to elucidate the impact of DOX and TA on the expression levels of Hsp90aa1, Hspa1a, Hspa4, and Hspa5 in the spleen tissues of rats. Sprague Dawley rats (Rattus norvegicus, male, 9–10 weeks old, 180 ± 20 g) were randomly divided into 4 groups: control, DOX (30 mg/kg cumulative), TA (50 mg/kg), and DOX + TA (5 mg/kg and 50 mg/kg, respectively). Subsequently, spleen tissues were collected from rats, and complementary DNA libraries were generated after the application process. The quantitative real‐time PCR method was used to detect and quantify the mRNA expression changes of the Hsp90aa1, Hspa1a, Hspa4, and Hspa5 genes our results showed that the mRNA expressions of the targeted genes were up‐regulated in rat spleen tissues exposed to DOX. However, this increase was remarkably suppressed by TA treatment. These findings suggest that TA may serve as a protective agent, mitigating the toxic effects of DOX in the rat spleen.

Deletion of mesencephalic astrocyte-derived neurotrophic factor delays and damages the development of white pulp in spleen

Mesencephalic astrocyte-derived neurotrophic factor (MANF) is an endoplasmic reticulum (ER) stress-induced protein, and it has been reported that ER stress and unfolded protein response (UPR) are closely related to the immune system. The spleen is an important immune organ and we have shown in our previous research that MANF is expressed in human spleen tissues. However, there have been limited studies about the effect of MANF on spleen development. In this study, we detected MANF expression in spleen tissues and found that MANF was expressed in the red pulp and marginal zone. Additionally, MANF was localized in the CD68+ and CD138+ cells of adult rat spleen tissues, but not in the CD3+ cells. We performed immunohistochemical staining to detect MANF expression in the spleen tissues of rats that were different ages, and we found that MANF+ cells were localized together in the spleen tissues of rats that were 1–4 weeks old. MANF was also expressed in CD68+ cells in the spleen tissues of rats and mice. Furthermore, we found that MANF deficiency inhibited white pulp development in MANF knockout mice, thus indicating that MANF played an important role in the white pulp development of rodent spleen tissues.

Efficacy of antibiotic combinations in an experimental sepsis model with Pseudomonas aeruginosa.

This study aimed to compare the efficacy of fosfomycin, colistin, tobramycin and their dual combinations in an experimental sepsis model. After sepsis was established with a Pseudomonas aeruginosa isolate (P1), antibiotic-administered rats were divided into six groups: Fosfomycin, tobramycin, colistin and their dual combinations were administered by the intravenous or intraperitoneal route to the groups. The brain, heart, lung, liver, spleen and kidney tissues of rats were cultured to investigate bacterial translocation caused by P1. Given the antibiotics and their combinations, bacterial colony counts in liver tissues were decreased in colistin alone and colistin plus tobramycin groups compared with control group, but there were no significant differences. In addition, a non-statistical decrease was found in the spleen tissues of rats in the colistin plus tobramycin group. There was a > 2 log10 CFU/ml decrease in the number of bacterial colonies in the kidney tissues of the rats in the fosfomycin group alone, but the decrease was not statistically significant. However, there was an increase in the number of bacterial colonies in the spleen and kidney samples in the group treated with colistin as monotherapy compared to the control group. The number of bacterial colonies in the spleen samples in fosfomycin plus tobramycin groups increased compared to the control group. Bacterial colony numbers in all tissue samples in the fosfomycin plus colistin group were found to be close to those in the control group. Colistin plus tobramycin combinations are effective against P. aeruginosa in experimental sepsis, and clinical success may be achieved. New in vivo studies demonstrating the ability of P. aeruginosa to biofilm formation in tissues other than the lung are warranted in future.

Tannic acid may ameliorate doxorubicin-induced changes in oxidative stress parameters in rat spleen.

Doxorubicin (DOX) is a potent and broad-spectrum drug widely used in the treatment of cancer. However, the toxicity and side effects of DOX on various organs limit its clinical use. Approaches using natural antioxidants with these drugs have the potential to alleviate negative side effects. The aim of this study was to investigate the potential protective effect of tannic acid, a polyphenolic compound found naturally in plants, against DOX-induced spleen toxicity. Expression levels of Alox5, Inos, IL-6, Tnf-α, Casp-3, Bax, SOD, GST, CAT and GPx genes were determined using cDNAs obtained from spleen tissues of rats treated with DOX, tannic acid and both. In addition, SOD, CAT, GPx and GST enzyme activities, and GSH and MDA levels were measured in tissues. In the spleen tissues, DOX caused a decrease in the level of GSH and an increase in the level of MDA. In addition, it was determined that DOX had a suppressive effect on CAT, GST, SOD and GPx mRNA levels and its enzyme activities, which are antioxidant system components. The mRNA expression levels of proinflammatory cytokine markers, apoptotic genes, and some factors involved in cell metabolism showed a change compared to the control after DOX application. However, as a result of tannic acid treatment with DOX, these changes approached the values of the control group. The findings showed that tannic acid had a protective effect on the changes in the oxidative stress and inflammation system in the rat spleen as a result of the application of tannic acid together with DOX.

Valproic Acid Attenuates Oxidative Damage in Rat Spleen Tissue Induced By Spinal Cord Damage

Events such as oxidative stress caused by spinal cord injury (SCI) are a serious condition because they negatively affect many organs. Alternative treatment options for this type of injury are quite limited. In this study, we planned to investigate the effect of oxidative damage on the spleen tissue of rats with spinal cord damage and the protective role of valproic acid (VPA) in this damage. Sixteen Wistar albino rats were divided into two equal groups. No treatment was administered to the rats in Group 1 (SCI-(Control), but a single dose of 300 mg/kg intraperitoneally VPA was administered to the rats in Group 2 (SCI-VPA). Superoxide dismutase (SOD) activities, total antioxidant status (TAS) and total oxidant status (TOS) levels were examined as markers of oxidative stress in spleen tissues taken after decapitation of rats. VPA treatment increased the SOD and TAS level but decreased the TOS level, indicating improved oxidative damage and impaired enzymatic antioxidant levels in spleen tissue homogenate damaged by SCI. We have observed that VPA, which has many beneficial properties, has a significant healing effect on spleen tissue affected by SCI-induced oxidative stress.

Mechanism of active ingredients in Periploca forrestii compound against rheumatoid arthritis based on integrative metabolomics and network pharmacology

In this study, an ultra-performance liquid chromatography-quadrupole time-of-flight high resolution mass spectrometer(UPLC-Q-TOF-HRMS) was used to investigate the effects of the active ingredients in Periploca forrestii compound on spleen metabolism in rats with collagen-induced arthritis(CIA), and its potential anti-inflammatory mechanism was analyzed by network pharmacology. After the model of CIA was successfully established, the spleen tissues of rats were taken 28 days after administration. UPLC-Q-TOF-HRMS chromatograms were collected and analyzed by principal component analysis(PCA), orthogonal partial least squares discriminant analysis(OPLS-DA), and MetPA. The results showed that as compared with the blank control group, 22 biomarkers in the spleen tissues such as inosine, citicoline, hypoxanthine, and taurine in the model group increased, while 9 biomarkers such as CDP-ethanolamine and phosphorylcholine decreased. As compared with the model group, 21 biomarkers such as inosine, citicoline, CDP-ethanolamine, and phosphorylcholine were reregulated by the active ingredients in P. forrestii. Seventeen metabolic pathways were significantly enriched, including purine metabolism, taurine and hypotaurine metabolism, glycerophospholipid metabolism, and cysteine and methionine metabolism. Network pharmacology analysis found that purine metabolism, glycerophospholipid metabolism, and cysteine and methionine metabolism played important roles in the pathological process of rheumatoid arthritis. This study suggests that active ingredients in P. forrestii compound can delay the occurrence and development of inflammatory reaction by improving the spleen metabolic disorder of rats with CIA. The P. forrestii compound has multi-target and multi-pathway anti-inflammatory mechanism. This study is expected to provide a new explanation for the mechanism of active ingredients in P. forrestii compound against rheumatoid arthritis.

Physiological and Immunological Study for the Effects of Onopordum Acanthium L. Seeds Oil in Male Rats Treated with CCL4

In this study, the attention was focused on the protective role of seeds oil from local Onopordum acanthium L. (cotton thistle) against tissues damage in the liver, kidney and spleen in male albino rats. Forty adult male rats were randomly divided into four equal groups including control group, rats were treated orally with seeds oil (0.5ml/kg), carbon tetrachloride (CCL4) injected group, and last group was intoxicated with CCL4 and daily treated with seed oil (0.5ml/kg). After four weeks of the experiment, rats were anaesthetized and blood was taken directly by cardiac puncture for the evaluation of studied parameters. Samples of liver, kidneys and spleen were fixed in 10% formalin for histological studies. From the obtained results, no significant changes were seen in the estimated parameters in the group treated with oil only. In the group injected with CCL4 and treated with oil extract, the level of serum lipids, liver enzymes, total serum bilirubin (TSB), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP) and white blood cells (WBCs) were significantly reduced in comparison with untreated CCL4 intoxicated group. The toxicity of CCL4 on the level of fasting blood sugar (FBS), angiotensin-converting enzyme (ACE), high-density lipoprotein (HDL), renal function parameters, hemoglobin and body weight were ameliorated with seeds oil. These effective roles were further supported by the histopathological improvement of the liver, kidney and spleen tissues of rats against CCl4. Conclusion: from the results of this study, it can be concluded that the extracted oil from local Iraqi Onopordum acanthium L. seeds reduced the tissue damages with an improvement of biochemical, hematological and immunological parameters during the four weeks of the experiment.

The immune modulatory role of marjoram extract on imidacloprid induced toxic effects in thymus and spleen of adult rats

Imidacloprid (IMID), one of environmental persistent neonicotinoid insecticides, has been used a long time ago and categorized from insecticide induced moderate toxicity by World Health Organization (WHO). Marjoram, is one of the most worldwide used herbs in Egypt due to its antioxidant, anti-inflammatory, anti-genotoxic, anti-mutagenic, anticoagulant, and beneficial effects. This study aimed to evaluate the protective role of marjoram extract on the immunotoxic response and oxidative stress induced by IMID in the immune lymphoid organs (thymus and spleen) of rats. Fifty adult male albino rats were divided randomly into five groups; negative and positive (distilled water) control, marjoram extract (200 mg/kg/day), IMID (22.5 mg/kg/day), marjoram extract + IMID (200 mg/kg +22.5 mg/kg) orally for 8 weeks. Marjoram pretreatment reversed reduced animals body, thymus and spleen weights attributed to IMID. It amended the significantly elevated total leukocytes, neutrophils percentage, increased immunoglobulin G and the significantly reduction of lymphocytes percentage, phagocytic activity, phagocytic index and lysozyme activity induced by IMID. Moreover, marjoram administration significantly reduced thymic and splenic gene expression of interleukin-1β, interleukin-6, tumor necrosis factor-α and increased interleukin-10, in addition, it decreased thymic and splenic contents of malondialdehyde and restored the reduced antioxidant enzymes' activities following IMID exposure. Marjoram ameliorated IMID induced histopathological alterations in thymus and spleen and adjusted IMID immunomodulatory effects by increased the downregulation of CD4 and CD8 immune reactive cell expression. Conclusion, Marjoram has a protective role to reverse IMID immune toxic effects in thymus and spleen tissues of rats by its antioxidant, anti-inflammatory and immunomodulatory defense mechanisms.

The Protective Effects of Vitamins A and E on Titanium Dioxide Nanoparticles (nTiO2)-Induced Oxidative Stress in the Spleen Tissues of Male Wistar Rats.

Titanium dioxide nanoparticles (nTiO2) can accumulate in different tissues and damage them with oxidative stress induction. Different components with antioxidant capacity can protect the tissues. So in this study, the protective effects of vitamin A and E on the nTiO2-induced oxidative stress in rats' spleen tissues were examined. Thirty-six male Wistar rats were randomly divided into 6 groups: Control 1 (received water), nTiO2, nTiO2 + vitamin E, nTiO2 + vitamin A, nTiO2 + vitamin A and E, and Control 2 (received olive oil). To investigate the status of oxidative stress, total antioxidant capacity (TAC), total oxidant status (TOS), and lipid peroxidation (LPO) were determined in spleen tissue as well as the activities of antioxidant enzymes, including glutathione peroxidase (GPx) and superoxide dismutase (SOD). Also, the gene expression of GPx, SOD, and nuclear factor-E2-related factor-2 (Nrf-2) were determined by qRT-PCR. To evaluate the spleen histopathological changes, H&E staining was carried out. nTiO2 significantly increased TOS and LPO levels, whereas it decreased TAC level, GPx and SOD activities, and gene expression of GPx, SOD, and Nrf-2 in spleen tissues of rats compared with controls (p < 0.05). In vitamin-treated rats, the levels of TOS and LPO significantly decreased, and the level of TAC, the activities of GPx and SOD, and the gene expression of GPx, SOD, and Nrf-2 increased compared to nTiO2 group (p < 0.05). These parameters are maintained near to normal levels. Histological findings confirmed the protective effects of these vitamins on tissue damage caused by nTiO2. Vitamin A and E can protect the spleen tissues from nTiO2-induced oxidative stress.

ВОЗДЕЙСТВИЕ ПРИРОДНОГО ГАЗА НА АКТИВНОСТЬ ТКАНИ СЕЛЕЗЕНКИ В ОНТОГЕНЕЗЕ

The chronobiological approach and biochemical research methods have revealed the age-related features of the ultradian rhythms of the content of total protein, albumin in rat spleen tissue normal, under the influence of natural gas and against the background of the introduction of a complex of antioxidants (vitamin E and thymalin). During the experiment, the rhythmic activity of the total protein and albumin content in rat spleen tissue during ontogenesis was compared with chronic exposure to sulfur-containing natural gas and the introduction of an antioxidant complex against intoxication. The revealed fluctuations in the content of total protein and albumin can be characterized as ultradian rhythms with periods from 20-40 to 60 minutes. The obtained experimental data indicate a decrease in the stability of spleen tissue with age and depletion of the antioxidant system of rats with aging. The materials of the article are of practical value for the development of methods for correcting the negative effects of oxidative stress in the context of intoxication.

Material Basis of the Difference between Hedysari Radix and Honey-Processed Hedysari Radix in Buzhong Yiqi.

Objective To compare the changes of chemical components of Hedysari Radix (HR) before and after honey-processing, and to explore the material basis of the difference between HR and honey-processed Hedysari Radix (HPHR) in Buzhong Yiqi. Methods Different compounds in aqueous extracts of HR and HPHR were analysed by UPLC-MS. A rat model of spleen qi deficiency was established. The rats were treated with different doses of water extracts of HR or HPHR, and pathological differences in spleen tissue, serum levels of D-xylose, gastrin (GAS) and amylase (AMS) interleukin-2 (IL)-2 and tumour necrosis factor-α (TNF-α), as well as spleen and thymus indices, were used as indicators. Differences in the efficacy of HR and HPHR in Buzhong Yiqi were studied. Results The research showed that compared with the blank group, the spleen tissue of rats in the model group showed spleen tissue damage, which mainly manifested as unclear boundaries between red pulp and white pulp, irregular spleen morphology and irregular arrangement, and the structure of white pulp destruction, less lymphocytes, the number of germinal centers decreased or atrophied. Compared with the model group, the middle and high dose groups of HR and HPHR had protective effects on spleen tissue of spleen-qi deficiency rats, and HPHR had a stronger effect; compared with those in the model group, rats in each treatment group showed remarkably higher serum D-xylose, GAS and AMS levels and thymus and spleen indices, and remarkably lower serum IL-2 and TNF-α levels, among which HPHR group showed better regulation effect than HR group. A total of 16 differential compounds were found in the aqueous extracts of HR and HPHR, of which 10 compounds in HPHR were up regulated, while 6 compounds were down regulated compare to HR. Conclusion The results indicated that both HR and HPHR can improve spleen qi deficiency syndrome of rats, the pharmacodynamic effect of the latter was better than the former. Differences in components of HR and HPHR potentially leading to variations in efficacy.

The curative effect of Cymbopogon citrates volatile oil against chlorambucil drug toxicity

Chlorambucil (CLB) is a bifunctional alkylating drug widely used as an anticancer agent and immunosuppressant. CLB mutagenicity, teratogenicity, and carcinogenicity are indicated based on their structure and clinical history. This study aims to evaluate the antigenotoxic effect of Cymbopogon citratus essential oil, CC, (75 mg/kg) against CLB (7.5 mg/kg) genotoxicity in rats. GC/MS for essential oil has identified 19 compounds representing approximately 99.7% Geranial was the most abundant (53.5%) followed by Neral (35%) and Myrcene (5.3%). The lowest was α-Muurolene (0. 1%). The marked damage was observed in total genomic DNA and total protein profile of CLB-intoxicated rat's spleen tissues. Lymphocytes single-strand breaks of treated rats were examined by comet assay after CC had ameliorated these effects in a time-dependent manner (5, 10, and 15 days) for spleen and after 48 hours for lymphocytes. In conclusion, this study suggests that Cymbopogon citrates oil possesses antigenotoxic potential in CLB-intoxicated rats. It can constitute natural, new, and safe co-therapeutics.

Establishment of the Mathematical Model for PMI Estimation Using FTIR Spectroscopy and Data Mining Method

To analyse the relationship between Fourier transform infrared （FTIR） spectrum of rat's spleen tissue and postmortem interval （PMI） for PMI estimation using FTIR spectroscopy combined with data mining method. Rats were sacrificed by cervical dislocation, and the cadavers were placed at 20 ℃. The FTIR spectrum data of rats' spleen tissues were taken and measured at different time points. After pretreatment, the data was analysed by data mining method. The absorption peak intensity of rat's spleen tissue spectrum changed with the PMI, while the absorption peak position was unchanged. The results of principal component analysis （PCA） showed that the cumulative contribution rate of the first three principal components was 96%. There was an obvious clustering tendency for the spectrum sample at each time point. The methods of partial least squares discriminant analysis （PLS-DA） and support vector machine classification （SVMC） effectively divided the spectrum samples with different PMI into four categories （0-24 h, 48-72 h, 96-120 h and 144-168 h）. The determination coefficient （R²） of the PMI estimation model established by PLS regression analysis was 0.96, and the root mean square error of calibration （RMSEC） and root mean square error of cross validation （RMSECV） were 9.90 h and 11.39 h respectively. In prediction set, the R² was 0.97, and the root mean square error of prediction （RMSEP） was 10.49 h. The FTIR spectrum of the rat's spleen tissue can be effectively analyzed qualitatively and quantitatively by the combination of FTIR spectroscopy and data mining method, and the classification and PLS regression models can be established for PMI estimation.

Effect of detoxification methods on the quality and safety of jojoba (Simmondsia chinensis) meal

This study was conducted to compare the effect of different detoxification methods on the composition and safety of defatted jojoba meal (DJM). Solvents, microwave, and microbiological (lactic acid bacteria, and bifidobacteria) treatments were used to detoxify and reduce the antinutrition factors in DJM. The results indicated that there were differences between treatments applied to detoxify DJM. Treatment of DJM with isopropanol and Lactobacillus acidophilus was able to reduce antinutrition factors and simmondsin. Detoxified-DJM that contained lower levels of antinutrition factors and simmondsin were further evaluated by feeding studies using experimental animals. After 8 weeks of feeding studies, there were no statistically significant differences between animal groups fed on basal diet, isopropanol-treated DJM, and Lactobacillus acidophilus-treated DJM in terms of body weight gain and relative organ weights. The group fed on untreated DJM showed a decrease in total albumin, globulin, protein, and lipid profile. The activities of liver enzymes were increased indicating incidence of liver dysfunction. Groups fed isopropanol-treated DJM and L. acidophilus-treated DJM exhibited improvement in serum parameters (i.e., total lipids, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, triglycerides, and liver function enzymes with no potential adverse health/toxic effects. Histopathological examinations of liver, kidney, and spleen tissues of rats fed on detoxified DJM showed the same histological features as the control rats. In conclusion, isopropanol and L. acidophilus could be applied for detoxification of DJM. Isopropanol and L. acidophilus detoxified-DJM could be recommended as a safe food or feed ingredient, since it had no potential adverse health/toxic effects. Practical applications This work described the effect of different methods for detoxification and degradation of antinutrition factors in DJM. The results indicated that the methods used, LAB and bifidobacteria, and isopropanol had high ability for detoxification of DJM. Lactobacillus acidophilus strain had the highest ability to reduce antinutrition factors and simmondsin. The incorporation of isopropanol-treated and L. acidophilus-treated DJM to basal diet had no potential adverse health/toxic effects. Therefore, isopropanol-treated and L. acidophilus-treated DJM could be recommended as safe food grade ingredients.

Nephroprotective Hepatoprotective Potential and Antioxidant Role of Carob Pods (Cerotonia siliqua L.) against Carbon Tetrachloride-induced Toxicity in Rats

Abstract: Objective: The aims of current study are the evaluation of the protective effect and antioxidant role of carob pods against carbon tetrachloride (CCl4)-induced oxidative stress, hepatotoxicity and nephropathy. Material and Methods: The present experiment was designed as I (control), II (0.5 ml/kg CCl4), III (%10 CP), IV (CCl4 0.5 ml/kg+%10 CP) groups. While rats in group I and III were fed with a diet without CCl4, II, and IV groups received twice 0.5 ml/kg/week, where IV group additionally received %10 CP supplementation for 50 days. The protective roles and antioxidant activity of the CP supplementation feed against CCl4-induced oxidative stress and toxicity were evaluated by histopathological changes, measuring hepatic and renal damage biomarkers (HRDB), antioxidant defence system constituents (ADSC) and malondialdehyde (MDA) parameters in the erythrocyte, liver, brain, kidney and spleen tissues of rats. Results: According to the results, the biochemical analysis showed a considerable increase in the serum AST (aspartate aminotransferase), ALT (alanin aminotransferase), GGT (gamma glutamyl transpeptidase) and LDH (lactate dehydrogenase) enzymes, creatinine and urea, and decrease in the group II as compared to that of I group. On contrary, such parameters were decreased in IV group as compared to that of group II. In addition, the results showed that CP supplementation diet restored the CCl4 induced MDA (malondialdehyde) and ADSC towards to control. The hepatoprotection of CP is further substantiated by the almost normal histological findings in IV group against degenerative changes in II group. Protective effects by CP are further substantiated by the almost normal HRDB for kidney and liver in IV treated group as against degenerative changes in the II treated rats. Conclusion: The results indicated that CP could be as an important as diet-derived antioxidants in preventing oxidative damage in the tissues by reducing the MDA or inhibiting the production of CCl4-induced free radicals and liver and kidney destruction. Key words: Carbon tetrachloride, Carob pods, Protective potential, Antioxidant role.

Discovery of a fluorinated 4-oxo-quinoline derivative as a potential positron emission tomography radiotracer for imaging cannabinoid receptor type 2.

The cannabinoid receptor type 2 (CB2) is part of the endocannabinoid system and has gained growing attention in recent years because of its important role in neuroinflammatory/neurodegenerative diseases. Recently, we reported on a carbon-11 labeled 4-oxo-quinoline derivative, designated RS-016, as a promising radiotracer for imaging CB2 using PET. In this study, three novel fluorinated analogs of RS-016 were designed, synthesized, and pharmacologically evaluated. The results of our efforts led to the identification of N-(1-adamantyl)-1-(2-(2-fluoroethoxy)ethyl)-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxamide (RS-126) as the most potent candidate for evaluation as a CB2 PET ligand. [(18) F]RS-126 was obtained in ≥99% radiochemical purity with an average specific radioactivity of 98 GBq/μmol at the end of the radiosynthesis. [(18) F]RS-126 showed a logD7.4 value of 1.99 and is stable invitro in rat and human plasma over 120min, whereas 55% intact parent compound was found invivo in rat blood plasma at 10min post injection. In vitro autoradiographic studies with CB2-positive rat spleen tissue revealed high and blockable binding which was confirmed in invivo displacement experiments with rats by dynamic PET imaging. Ex vivo biodistribution studies confirmed accumulation of [(18) F]RS-126 in rat spleen with a specificity of 79% under blocking conditions. The moderate elevated CB2 levels in LPS-treated mice brain did not permit the detection of CB2 by [(18) F]RS-126 using PET imaging. In summary, [(18) F]RS-126 demonstrated high specificity toward CB2 receptor invitro and invivo and is a promising radioligand for imaging CB2 receptor expression. Cannabinoid receptor type 2 (CB2) is an interesting target for PET imaging. Specific binding of [(18) F]RS-126 in CB2-positive spleen tissue (white arrow head) was confirmed in invivo displacement experiments with rats. Time activity curve of [(18) F]RS-126 in the spleen after the addition of GW405833 (CB2 specific ligand, green) demonstrates faster radiotracer elimination (blue) compared to the tracer only (red).

Expression and significance of chemokine receptors CXCR3, CCR5 and CCR3 in the spleen tissues of rats with cirrhosis and hypersplenism

Objective To investigate the expressions of T helper cell 1 (Th1)-associated chemokine receptors CXCR3, CCR5 and T helper cell 2 (Th2)-associated chemokine receptor CCR3 in the spleen tissues of rats with cirrhosis and hypersplenism and probe into the balance between Th1/ Th2 lymphocyte subsets. Methods Experimental study was adopted.Forty-six male SD rats were randomized into the hypersplenic group ( n =36)and the control group ( n =10).In the hypersplenic group, the rats were fed with 40% CCl4 peanut oil solution (3. 0 mL/ kg, twice per week)and 15% white spirit for 8 weeks to build the hypersplenic model.The rats in the control group received normal feeding.The animal models with cirrhosis and hypersplenism were confirmed by liver function test, routine blood test, HE staining and Masson staining after visual inspection.The expressions of chemokine receptors of CXCR3, CCR5 and CCR3 were detected by immunohistochemical staining and Western blot.Measurement data with normal distribution were presented as ±s.Comparison between groups was done using the independent sample t test. Results Results of visual inspection: the rats in the hypersplenic group suffered from severe hair-shedding, metal fatigue and inappetence, with hair dimming and inactivity.There were rats dead successively 5 weeks after model establishment and 19 rats finally survived.The rats in the control group had color and gloss hair, with good appetite and spirits.They were active and sensitive to external stimulation. Changes of pathological morphology in liver: in the hypersplenic group, the fibers became denser and disordered, making normal structure of liver tissues destroyed.The hepatic lobules separated by fibrous bundle and proliferative hepatic cell mass were segmented and surrounded by thick fibrous, leading to the formation of pseudolobule. Disorganized hepatocytes suffused adipocytes, the nucleus of heterocysts enlarged or even multinucleated cells appeared.There was no change in the control group.Changes of pathological morphology in spleen: the rats in the hypersplenic group had slightly swelling spleen with the areas of red pulp increased and whit pulp disappeared gradually.Vascular endothelium became thicker and proliferated.Thickened central artery and fibrosis were depicted.Splenic sinusoid extended.There was no change of spleen tissues in the control group.Changes of liver function: the levels of ALT and AST of rats were (264±111)U/ L and (687±299)U/ L in the hypersplenic group, which were significantly different from (27±8)U/ L and (124±20)U/ L in the control group ( t =5. 64, 4. 98, P 0.05).The rates of positive cells of CXCR3 and CCR5 was 52%±9% and 19%±5% in the hypersplenic group, which were significantly different from 21%±5% and 10%±3% in the control group ( t =17. 31, 8. 21, P 0.05).Results of Western blot test: the relative expressions of CXCR3 and CCR5 were 2. 45±0.85 and 0.94±0.48 in the hypersplenic group, which were significantly different from 1. 31±0. 95 and 0.32±0. 26 in the control group ( t =2. 62, 2. 91, P <0. 05). The relative expression of CCR3 was 0. 47±0. 27 in the hypersplenic group, which was significantly different from 0.92±0.67 in the control group ( t =-2. 18, P <0.05). Conclusion The abnormal expression of chemokine receptors in the spleen tissues of rats with cirrhosis and hypersplenism induced by CCl4 suggests that functional imbalance of Th1/ Th2 lymphocyte subsets may play an important role in the regulation of peripheral blood cytopenia. Key words: Liver cirrhosis; Hypersplenism; Chemokine receptors; Peripheral blood cytopenia

Fenofibrate treatment of rats with experimental autoimmune myocarditis by alleviating Treg/Th17 disorder.

ObjectiveTo investigate the curative effect of fenofibrate on rats with experimental autoimmune myocarditis (EAM) and its immunological mechanism.Material and methods Twenty-four rats were equally randomised into three groups: an EAM group, fenofibrate group, and control group, then a subcutaneous injection of purified pig cardiac myosin was given to the EAM group rats and the fenofibrate group, while equivalent normal saline (NS) was given to the control group. After that, the fenofibrate group received fenofibrate by gavage (100 mg/kg/d) and equivalent NS was given to the other groups, lasting for 17 days. Then the rats were sacrificed in order to take heart tissues; HE staining and qRT-PCR method was used to assess the severity of heart failure and mRNA level of cytokines; NK-κB protein content was analyzed by Western-blot. Healthy rat spleen tissue was prepared for splenocyte suspension. Subsequently, splenocytes were administrated similarly to the test in vivo for detecting cytokine mRNA levels.ResultsCompared with the control group, heart weight in EAM group was heavier than in the other groups (p < 0.05), and there was severe inflammatory cell infiltration in heart tissue of the EAM group. Th17 cell-related cytokines mRNA levels in the EAM group/induction group were evidently higher than in other groups (p < 0.05); FOX-p3 mRNA level in the EAM group/induction group was lower than other groups, mRNA levels of IL-10 and FOX-p3 in the fenofibrate group were higher than in the EAM group/induction group (p < 0.05). Fenofibrate could significantly inhibit the up-regulation of NF-κB protein in EAM rats (p < 0.05).ConclusionsBy inhibiting the development of Th17 cells and promoting the differentiation of Tregs, fenofibrate alleviated Treg/Th17 disorder and inhibited inflammation in rats with EAM, thus improving the prognosis.

Discovery of a high affinity and selective pyridine analog as a potential positron emission tomography imaging agent for cannabinoid type 2 receptor.

As part of our efforts to develop CB2 PET imaging agents, we investigated 2,5,6-substituted pyridines as a novel class of potential CB2 PET ligands. A total of 21 novel compounds were designed, synthesized, and evaluated for their potency and binding properties toward human and rodent CB1 and CB2. The most promising ligand 6a was radiolabeled with carbon-11 to yield 16 ([(11)C]RSR-056). Specific binding of 16 to CB2-positive spleen tissue of rats and mice was demonstrated by in vitro autogadiography and verified in vivo in PET and biodistribution experiments. Furthermore, 16 was evaluated in a lipopolysaccharid (LPS) induced murine model of neuroinflammation. Brain radioactivity was strikingly higher in the LPS-treated mice than the control mice. Compound 16 is a promising radiotracer for imaging CB2 in rodents. It might serve as a tool for the investigation of CB2 receptor expression levels in healthy tissues and different neuroinflammatory disorders in humans.

Role of vitamin C and selenium in attenuation of nicotine induced oxidative stress, P53 and Bcl2 expression in adult rat spleen

Forty adult female rats were randomly divided into four groups: control, nicotine, nicotine+vitamin C and nicotine+selenium group. Splenic tissues concentrations of thiobarbituric acid reactive substances (TBARS), nitric oxide, superoxide dismutase (SOD) and catalase (CAT) activities were measured. The P53 and Bcl2 proteins were detected by Western blot and their expression in splenic tissues were measured by quantitative real time PCR in all groups. Compared to control group, nicotine increased the concentrations of TBARS and nitric oxide significantly. However, Vit. C or Se supplementation with nicotine caused a significant decrease in these concentrations. SOD and CAT activities of nicotine group decreased significantly compared to control group. Treatment with Vit. C or Se plays a significant role in elevation of SOD and CAT activities. In splenic tissues, nicotine significantly decreases the protein levels and the mRNA expression of P53 and increases the protein levels of Bcl2 and its expression. Administration of Vit. C. to nicotine-treated rats completely reversed the decrease in P53 levels and its mRNA expression and the increase in Bcl2 levels and its mRNA expression to the control values. In contrast, Se administration did not induce any significant changes in these genes levels or expressions compared to nicotine group. Conclusion: Vit. C supplementation to nicotine treated rats was more effective than selenium in attenuation of nicotine-induced oxidative stress, p53 and Bcl2 expression in rat spleen tissues.