Study of dexamethasone, baicalin and octreotide on brain injury of rats with severe acute pancreatitis

Recent Advances in Biologically Active Ingredients from Natural Drugs for Sepsis Treatment

Sepsis refers to the dysregulated host response to infection; its incidence and mortality rates are high. It is a worldwide medical problem but there is no specific drug for it. In recent years, clinical and experimental studies have found that many monomer components of traditional Chinese medicine have certain effects on the treatment of sepsis. This paper reviews the advances in research on the active ingredients of traditional Chinese medicine involved in the treatment of sepsis in recent years according to their chemical structure; it could provide ideas and references for further research and development in Chinese materia medica for the treatment of sepsis.

Incidence and outcomes of pancreatic encephalopathy in patients with acute pancreatitis: a systematic review and meta-analysis

Pancreatic encephalopathy (PE) is a lethal complication of acute pancreatitis (AP), but its clinical characteristics and prognosis remain obscure. Herein, we performed a systematic review and meta-analysis to evaluate the incidence and outcomes of PE in AP patients. PubMed, EMBASE, and China National Knowledge Infrastructure were searched. Based on the data from cohort studies, the incidence and mortality of PE in AP patients were pooled. Based on the individual data from case reports, logistic regression analyses were performed to identify the risk factors for death in PE patients. Among 6702 papers initially identified, 148 were included. Based on 68 cohort studies, the pooled incidence and mortality of PE in AP patients were 11% and 43%, respectively. The causes of death were clearly reported in 282 patients, of which the most common was multiple organ failure (n = 197). Based on 80 case reports, 114 AP patients with PE were included. The causes of death were clearly reported in 19 patients, of which the most common was multiple organ failure (n = 8). Univariate analyses showed that multiple organ failure (OR = 5.946; p = 0.009) and chronic cholecystitis (OR = 5.400; p = 0.008) were the significant risk factors of death among patients with PE. PE is not a rare complication of AP and indicates poor prognosis. Such a high mortality of PE patients may be attributed to its coexistence of multiple organ failure.

Dysregulated B7H4/JAK2/STAT3 Pathway Involves in Hypertriglyceridemia Acute Pancreatitis and Is Attenuated by Baicalin

BACKGROUND

Patients with hypertriglyceridemia (HTG) are prone to develop more severe acute pancreatitis (AP). However, the specific molecular mechanism still has not been elaborated clearly, and effective drugs for treating HTG-AP are not yet readily available. Baicalin is an ingredient isolated from a natural product that with potential to attenuate inflammation and pain in AP.

AIMS

The aim of the present study was to explore the effect of baicalin on HTG-AP and the possible mechanism involved.

METHODS

A mouse model of HTG-AP was successfully established by administering Poloxamer 407 and L-arginine intraperitoneally. We analyzed pathological changes, and performed TUNEL staining, DHE staining, and western blot to detect apoptosis, inflammation, oxidative stress, and B7H4/JAK2/STAT3 signaling in the pancreas.

RESULTS

Treatment with baicalin decreased serum triglyceride, cholesterol, lipase, amylase levels, and attenuated pancreatic edema. After intervention with baicalin, apoptosis and inflammation in HTG-AP mice were alleviated, as indicated by the decrease of Bax, cleaved-caspase-3, IL-6, TNF-α, and IL-1β. Baicalin also alleviated oxidative stress by decreasing NOX2, increasing SOD2 protein expression, and regulating Nrf2/Keap1 signaling in HTG-AP mice. Furthermore, baicalin decreased the upregulated B7H4/JAK2/STAT3 pathway in HTG-AP.

CONCLUSIONS

In conclusion, our data suggested that baicalin could attenuate HTG-AP, possibly through regulating B7H4/JAK2/STAT3 signaling.

Octreotide-mediated neurofunctional recovery in rats following traumatic brain injury. Role of H2S, Nrf2 and TNF-α

Purpose:

To explore the role and mechanisms of octreotide in neurofunctional recovery in the traumatic brain injury (TBI) model.

Methods:

Rats were subjected to midline incision followed by TBI in the prefrontal cortex region. After 72 hours, the behavioural and neurological deficits tests were performed, which included memory testing on Morris water maze for 5 days. Octreotide (15 and 30 mg/kg i.p.) was administered 30 minutes before subjecting to TBI, and its administration was continued for three days.

Results:

In TBI-subjected rats, administration of octreotide restored on day 4 escape latency time (ELT) and increased the time spent in the target quadrant (TSTQ) on day 5, suggesting the improvement in learning and memory. It also increased the expression of H₂S, Nrf2, and cystathionine-γ-lyase (CSE) in the prefrontal cortex, without any significant effect on cystathionine-β-synthase. Octreotide also decreased the TNF-α levels and neurological severity score. However, co-administration of CSE inhibitor (D,L-propargylglycine) abolished octreotide-mediated neurofunctional recovery, decreased the levels of H₂S and Nrf2 and increased the levels of TNF-α.

Conclusions:

Octreotide improved the neurological functions in TBI-subjected rats, which may be due to up-regulation of H₂S biosynthetic enzyme (CSE), levels of H₂S and Nrf2 and down-regulation of neuroinflammation.

Dexamethasone inhibits NF‑кBp65 and HMGB1 expression in the pancreas of rats with severe acute pancreatitis

Severe acute pancreatitis (SAP) starts as a local inflammation of pancreatic tissue that induces the development of multiple extra-pancreatic organ dysfunction; however, the underlying mechanisms remain unclear. The present study was designed to evaluate the effect of dexamethasone (DXM) on pancreatic damage and to investigate the role of high-mobility group box-1 (HMGB1) and nuclear factor-κB (NF-κBp65) in the development of SAP in animal and cell models. For the in vivo experiment, 35 Sprague-Dawley rats were randomly assigned to three groups: The sham-operation control group, the SAP group and the DXM treatment group. Histological analysis revealed that, when DXM was infused into SAP rats, edema formation and structural alterations with necrosis were reduced, and the number of apoptotic cells was markedly reduced. In addition, compared with the SAP group, the expression level of HMGB1 was significantly decreased in the nucleus and the expression level of NF-κBp65 was significantly decreased in the cytoplasm from rats treated with DXM. In vitro, DXM was able to suppress the apoptosis and cell death induced by caerulein (CAE), and DXM could suppress the expression of NF-κBp65 and HMGB1 induced by CAE, as demonstrated by western blotting and immunofluorescence analysis. Therefore, these results provide an experimental basis for investigating the underlying therapeutic mechanisms of DXM treatment for SAP.

Therapeutic effects of Saussurea involucrata injection against severe acute pancreatitis- induced brain injury in rats

OBJECTIVES

To observe the therapeutic effects of Saussurea involucrata (Sau) injection against severe acute pancreatitis (SAP)-induced brain injury.

METHODS

Sodium taurocholate-induced SAP-modeled rats were equally randomized into an SAP model group (SAP group) and a Sau treated group (Sau  +  S group). Healthy rats were equally randomized into a Sau treated group (Sau  +  H group) and a sham operation group (SO group). Serum amylase levels, endothelin-1 (ET-1) and nitric oxide (NO) contents were determined by optical turbidimetry, ELISA and nitrate reductase method respectively. Western blot was used to detect protein expression levels of phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt), ET-1, inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) while mRNA levels of these biomarkers in brain tissue were measured by quantitative real-time PCR. Furthermore, pathological changes, as well as all above indexes of pancreas and brain, were observed at 6, 24 and 48 h after administration.

RESULTS

There was a significant difference in mortality between SAP and Sau  +  S groups (P  <  0.05). Serum amylase levels, ET-1 and NO contents, ET-1/NO ratio, relative expression levels of ET-1 and iNOS protein/mRNA of brain tissue in Sau + S group were lower than those in SAP group at 24 and 48 h post-operation (P  <  0.05 or 0.01), meanwhile, pancreas and brain pathological scores showed similar tendency (P  <  0.01). However, both protein and mRNA levels of PI3K, Akt and eNOS of brain tissue in Sau + S group were higher than those in SAP group (P  <  0.05 or P  <  0.01). There were no significant differences in all indexes between Sau + H and SO groups at all designated time points (P  >  0.05).

CONCLUSIONS

Sau injection has therapeutic effects on SAP-induced brain injury in rats.

Acanthopanax versus 3-Methyladenine Ameliorates Sodium Taurocholate-Induced Severe Acute Pancreatitis by Inhibiting the Autophagic Pathway in Rats

Objectives. To observe the therapeutic effects of Acanthopanax and 3-methyladenine against severe acute pancreatitis (SAP). Methods. Sodium taurocholate-induced SAP rats were equally randomized into a SAP group, an Acanthopanax group, and a 3-methyladenine group. Serum amylase levels were determined by ELISA; protein and mRNA expression levels of nucleus nuclear factor kappa B (NF-κB) p65, light chain 3II (LC3-II), and Beclin-1 and mRNA expression levels of Class III phosphatidylinositol 3-kinase (PI3K-III) in pancreas tissue were detected by Western blot and quantitative real-time PCR, respectively; mortality and pathological change of the pancreas were observed at 3, 12, and 24 h after operation. Results. There was no significant difference in mortality between SAP group and both treatment groups (P > 0.05). Serum amylase levels, protein, and mRNA expression levels of nucleus NF-κB p65, LC3-II, and Beclin-1 protein, mRNA expression levels of PI3K-III, and pathological score of the pancreas in both treatment groups were significantly lower than those in SAP group at 12 and 24 h after operation (P < 0.05 or 0.01). The number of autophagosomes and autophagolysosomes of pancreatic acinar cells in both treatment groups was smaller than that in SAP group at 12 and 24 h. Conclusions. Acanthopanax and 3-methyladenine had similar therapeutic effects against SAP in rats. The mechanism may be through inhibiting abnormal autophagy activation of pancreatic acinar cells.

Octreotide Protects the Mouse Retina against Ischemic Reperfusion Injury through Regulation of Antioxidation and Activation of NF-κB

Somatostatin (SST), an endogenous peptide, may exert anti-inflammatory and neuroprotective effects on retinal injury induced by ischemia. Retinal ischemic reperfusion (I/R) injury always produces many reactive oxygen species (ROS), which can aggravate the tissue damage. The effects of octreotide (OCT), a SST analogue, on retinal I/R injury and ROS formation, are not very clear. In this study, we observed the effects of OCT on morphological changes, oxidative stress, and cell death, induced by retinal I/R injury. The activation of nuclear factor κB (NF-κB) and intercellular adhesion molecule-1 (ICAM-1) were further evaluated in I/R retina treated with or without OCT. The retinal layer thickness was increased at 1 day after I/R and decreased at 7 days after I/R (P < 0.05). This effect was associated with increase in MDA and ROS levels (P < 0.05). The Tunel-positive cells increased and the number of ganglion cell layer (GCL) neurons decreased significantly after I/R injury. The expression of p-p65 and ICAM-1 increased significantly in I/R retinas (P < 0.05). Each effect was markedly attenuated by application of OCT. These data indicate that OCT protects the retina against retinal I/R damage, which could be through inhibition of oxidative stress and downregulation of NF-κB and ICAM-1 expression.

Modular analysis of bioinformatics demonstrates a critical role for NF-κB in macrophage activation

To achieve the goal of identifying the gene groups that regulated macrophage activation, a total of 925 differentially expressed genes of activated macrophages were found at the intersection of the three series (GSE5099-1, GSE5099-2, and GSE18686) from the Gene Expression Omnibus (GEO) database, and a sub-network was constructed based on the protein-protein interaction (PPI) network. Four communities (K = 3) were identified from the sub-network using the CFinder software. Community 1 was considered as the gene group of interest base on the heat map. GO-BP and KEGG enrichment analysis with the DAVID software showed that the functions of the 14 genes in community 1 were mainly related to the NF-κB pathway. A network was constructed using the Cytoscape software. The diagram showed that STAT1, NFKBIA, NFKAIB, JUN, and RELA were the key genes in the regulation of macrophage activation. Among these genes, RELA (NF-κB P65) was an important member of the NF-κB family, while NFKBIA (IκBα) and NFKAIB (IκBβ) were the inhibitory factors of NF-κB. Small molecules capable of regulating these five genes were identified via the CMap software, and a network diagram was generated using the Cytoscape software to provide a reference for the development of new drugs that regulate macrophage activation.

The effect of erythropoietin to pulmonary injury and mast cells secondary to acute pancreatitis

Background

Acute pancreatitis is a life-threatening necroinflammatory disease that is characterized by systemic inflammatory response syndrome and acute lung injury even in its very first days. Erythropoietin (EPO) is a hormone considered as an antiapoptotic and cytoprotective with observed receptors of anti-inflammatory effect on organs apart from the liver and the kidneys. In this study, the effects of EPO on pulmonary mast cells and on secondary injury caused by acute pancreatitis are investigated.

Methods

Twenty one Wistar Albino rats were divided into three groups—sham, control, and EPO groups—with 7 rats per group. Pancreatitis was induced by administering 4.5% sodium taurocholate into the pancreatic duct. A 1000 U/kg/day dosage (three times) of EPO was administered to the EPO group. Blood urea nitrogen (BUN), creatinine, amylase, and troponin I in the serum were studied; and lung, kidney, brain, and heart tissues were examined histopathologically.

Results

There were no histopathological changes in the other organ tissues except for the lung tissue. Compared to the control group, the EPO group showed significantly reduced alveolar hemorrhage, septal neutrophil infiltration, lung wall thickness score, and mast cell count in the lung tissue.

Conclusions

Administration of EPO reduces the mast cell count and lung wall thickness, and it reduces the alveolar hemorrhage and septal infiltration induced by acute pancreatitis.

In vitro effects of emodin on peritoneal macrophages that express membrane-bound CD14 protein in a rat model of severe acute pancreatitis/systemic inflammatory response syndrome

Emodin is the main active constituent of rhubarb and is often used in Chinese herbal medicine for the treatment of systemic inflammatory response syndrome (SIRS). The present study aimed to determine the in vitro effects of emodin on the expression of membrane-bound cluster of differentiation 14 (mCD14) protein in peritoneal macrophages (pMΦs). The severe acute pancreatitis (SAP)̸SIRS model was established in Sprague‑Dawley (SD) rats via retrograde injection of 1.5% sodium deoxycholate into the common biliopancreatic duct. The 40 SD rats were randomly divided into the sham‑operated (n=10) group (SO) and the model group (n=30). After 24 h, pMΦs were harvested and the model group was randomly divided into three subgroups (n=10 per group), the 5 µg/ml emodin group (EMO), the 0.1 µmol/ml dexamethasone group (DEX) and the SIRS/SAP group (SI). Treatment agents were administered following macrophage adhesion for 24 h. Compared with that of the SO group, the SI group showed significantly increased pathological changes (P<0.01). Compared with that of the SO group, mCD14 expression in pMΦs was significantly decreased in the SI group (P<0.01). Additionally, compared with that of the SI group, mCD14 expression in pMΦs was significantly increased in the EMO group (P<0.01) and in the DEX group (P<0.01). Compared with that of the DEX group, mCD14 expression in pMΦs was significantly increased in the EMO group (25.60±2.79 vs. 20.87±1.99; P<0.01). The pathological changes observed in the pancreas of rats in the model groups were more severe than that of the SO group. Moreover, mCD14 expression levels in pMΦs were significantly decreased in the SI group. The pathological changes of each intervention group improved to various degrees, particularly in the EMO group.

In vitro effects of emodin on peritoneal macrophage intercellular adhesion molecule-3 in a rat model of severe acute pancreatitis/systemic inflammatory response syndrome

Rhubarb is often used in Chinese herbal medicine for the treatment of systemic inflammatory response syndrome (SIRS). Emodin is the main active constituent of rhubarb. This study was performed to investigate the in vitro effects of emodin and dexamethasone on peritoneal macrophage (pMΦ) phagocytosis and the expression of intercellular adhesion molecule-3 (ICAM-3). A total of 40 Sprague-Dawley (SD) rats were randomly divided into sham surgery (n=10) and model groups (n=30). After 24 h, pMΦs were harvested and the model group was randomly divided into three subgroups (n=10 rats/subgroup): the 5 μg/ml emodin, 0.1 μmol/ml dexamethasone and control groups. The drugs were administered following macrophage (MΦ) adhesion for 24 h. pMΦ phagocytosis was significantly increased in the emodin group compared to that in the control group. Moreover, pMΦ phagocytosis was significantly increased in the emodin group compared to that in the dexamethasone group. The expression of ICAM-3 was significantly increased in the emodin group compared to that in the control group. The expression of ICAM-3 was significantly increased in the emodin group compared to that in the dexamethasone group. The expression of ICAM-3 was significantly increased in the emodin and dexamethasone groups compared to that in the control group. pMΦ phagocytosis and ICAM-3 expression were significantly increased following emodin treatment compared to those in the control and dexamethasone groups, indicating that emodin may enhance pMΦ phagocytosis and apoptotic cell clearance by altering ICAM-3 expression.

The protection by octreotide against experimental ischemic stroke: up-regulated transcription factor Nrf2, HO-1 and down-regulated NF-κB expression

BACKGROUND

Inflammatory and oxidative damage play a pivotal role in cerebral ischemic pathogenesis and may represent a therapeutic target. Octreotide (OCT) has been proved to elicit a variety of biological effects through its anti-inflammatory and anti-oxidant properties in the treatment of severe acute pancreatitis and ischemia-reperfusion injury in retina and intestine. However little is known regarding the effect of OCT in ischemic stroke. Here, we designed this study to investigate the protective effect of OCT in ischemic stroke and explore the potential underlying mechanisms.

METHODS

Male Sprague-Dawley rats were subjected to permanent middle cerebral artery occlusion (pMCAO) and randomly divided into four groups: Sham (sham-operated), MCAO (pMCAO+0.9% saline), OCT-L (pMCAO+OCT 50μg/kg) and OCT-H (pMCAO+OCT 100μg/kg) groups. OCT was administered intraperitoneally immediately after stroke. Neurological deficit scores, infarct volume and brain water content were measured at 24h after stroke. Immunohistochemical staining and western blot were used to analyze the expressions of Nrf2, HO-1 and NF-κB. SOD and MDA were measured by spectrophotometer.

RESULTS

Compared with MCAO group, OCT significantly alleviated neurological deficit, lessened infarct volume and brain edema (P<0.05), upregulated the expression of Nrf2, HO-1 and SOD (P<0.05), and decreased the expression of NF-κB and MDA (P<0.05).

CONCLUSIONS

OCT protected the brain against cerebral ischemic damage; this effect may be through upregulation of transcription factor Nrf2, HO-1 and downregulation of NF-κB expression.