Protective effect of low-molecular-weight heparin on pancreatic encephalopathy in severe acute pancreatic rats

Effectiveness and safety of low molecular weight heparin in the management of acute pancreatitis: a systematic review and meta-analysis

BACKGROUND

Recent studies suggest that low-molecular-weight heparin (LMWH) may play a role in mitigating the severity of acute pancreatitis (AP). This systematic review and meta-analysis aims to synthesise existing evidence on the effectiveness and safety of LMWH in the treatment of moderately-severe and severe AP.

METHODS

This systematic review and meta-analysis was conducted in accordance with the 2020 update of the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions. The systematic search was conducted in MEDLINE, the Cochrane Central Register of Controlled Trials, Scopus, and EMBASE, covering studies published up to February 2024. Randomised controlled trials (RCTs) and observational studies (n-RCTs) that reported the differences in the outcomes of AP for patients receiving LMWH in addition to the standard treatment (Intervention), compared to patients managed by standard treatment without LMWH (Control) were eligible. A random-effects model was used to calculate the pooled relative risk (RR) and mean differences (MD) with the corresponding 95% CI.

RESULTS

Thirteen studies were included in the meta-analysis, all published between 2004 and 2022. Eight studies were RCTs, and five were n-RCTs. Data from 13,709 patients (6.971 Interventions and 6.738 Controls) were analysed. The comparison of Intervention and Control groups showed the superiority of LMWH to standard treatments in terms of overall mortality (RR = 0.44, 95% CI = 0.31; 0.64, P < 0.0001, I2 = 51%), acute necrotic collections (RR = 0.24, 95% CI = 0.09; 0.62, P = 0.003, I2 = 0%), and organ failure (RR = 0.67, 95% CI = 0.48; 0.93, P = 0.02, I2 = 78%). The Intervention group showed superior outcomes compared with the Control group for gastrointestinal bleeding (RR = 0.64, 95% CI = 0.44; 0.94, P = 0.02, I2 = 0%), length of hospital stay (MD= - 6.08, 95% CI = - 10.08; - 2.07, P = 0.003, I2 = 98%), need for operative interventions (RR = 0.50, 95% CI = 0.29; 0.87, P = 0.01, I2 = 61%), and vascular thrombosis (RR = 0.43, 95% CI = 0.31; 0.61, P < 0.00001, I2 = 0%).

CONCLUSIONS

Moderate to high-quality evidence suggests that early intervention with LMWH could improve the prognosis of non-mild AP in terms of mortality, organ failure, and decreased incidence of vascular thrombosis. In light of our findings, integrating LMWH into the treatment regimen for moderate-severe to severe AP is advocated.

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.

Prophylactic low-molecular-weight heparin administration protected against severe acute pancreatitis partially by VEGF/Flt-1 signaling in a rat model

BACKGROUND

The present study was aimed to explore the effects and the underlying mechanism of prophylactic low-molecular-weight heparin (LMWH) treatment on taurocholate-induced severe acute pancreatitis (SAP) in a rat model.

METHODS

Rat SAP model was induced by injection of 4% sodium taurocholate into the pancreatic duct. LMWH was applied half an hour before the induction of pancreatitis at the dose of 200 IU/kg subcutaneous injection. The rats were euthanized at 1 h, 6 h, and 12 h after taurocholate-induced SAP. The inflammatory and oxidative response markers were assessed. And the vascular endothelial growth factor (VEGF) and Fms-related tyrosine kinase 1 (Flt-1) expression were evaluated by immunohistochemistry (IHC) and western blot methods.

RESULTS

The expression of inflammatory and oxidative response markers increased after induction of SAP. IHC and western blot results showed the VEGF and Flt-1 expression were increased in SAP group. Prophylactic LMWH administration reduced the inflammatory and oxidative response markers expression and decreased the expression of VEGF and Flt-1.

CONCLUSIONS

This study suggested that prophylactic LMWH treatment mitigated the severity of pancreatitis in rat SAP model by anti-inflammation and oxidative response. The underlying mechanism may result from downregulating VEGF/Flt-1 signaling of LMWH in SAP rat model.

The efficacy of low molecular weight heparin in severe acute pancreatitis: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The effects of low molecular weight heparin (LMWH) on severe acute pancreatitis (SAP) have been controversial. We aimed to evaluate the efficacy of LMWH on prognosis of SAP by systematic review and meta-analysis.

METHODS

We searched relevant studies published up to March 2019 in five databases (MEDLINE/PubMed, EMBASE, the Cochrane Central Register of Controlled Trials in Cochrane Library, China National Knowledge Infrastructure, and the Chinese Journal of Science and Technology of VIP database).

RESULTS

Sixteen randomized controlled trials with 1625 patients were included in the final analysis. Most studies were from China. In analysis of laboratory parameters and clinical scores, SAP patients receiving LMWH treatment had lower white blood cell counts, C-reactive protein level, Acute Physiology and Chronic Health Evaluation II score, and computed tomography severity index. In clinical outcomes, SAP patients who received LMWH treatment had shorter hospital stay (pooled mean difference [95% confidence interval; CI] -8.79 [-11.18, -6.40], P < .01), lower mortality (pooled risk ratio [RR] [95% CI] 0.33 [0.24-0.44], P < .01), lower incidences of multiple organ failure (pooled RR [95% CI] 0.34 [0.23-0.52], P < .01), pancreatic pseudocyst (pooled RR [95% CI] 0.49 [0.27-0.90], P = .02), and operation rate (pooled RR [95% CI] 0.39 [0.31-0.50], P < .01).

CONCLUSIONS

LMWH could improve the prognosis of SAP, and has a potential role in reducing hospital stay, mortality, incidences of multiple organ failure, pancreatic pseudocyst, and operation rate.

Low molecular weight heparin treatment of acute moderate and severe pancreatitis: A randomized, controlled,open-label study

BACKGROUND/AIMS

Acute pancreatitis (AP) runs a moderately severe and severe course in 20%-30% of cases. The purpose of the present study was to determine the effect of low molecular weight heparin (LMWH) for the prevention of pancreatic necrosis (PN) in moderately severe and severe AP (MSAP).

MATERIALS AND METHODS

A total of 100 patients with MSAP were randomized to receive either standard care (SC) or SC plus LMWH. LMWH was administered at 1 mg/kg via subcutaneous injection twice a day between days 1 and 7. The revised Atlanta criteria were used in the diagnosis of MSAP. Patients with a Harmless AP Score of >1 and a Balthazar computed tomography (CT) score of D and E were included in the study.

RESULTS

The mean age±SD of the patients (46 male and 54 female) was 52±19 years (range, 17-100). There were 50 patients in each group. On admission, clinical and laboratory parameters and Balthazar CT scores were similar between the groups. Initially, PN was present in one patient in the LMWH group and two in the SC group. Over the course, PN developed in 3 (6.1%) patients in the LMWH group and 11 (22.9%) in the SC group (p<0.05). Local and systemic complications were significantly lower in the LMWH group (p<0.05). No hemorrhagic complication occurred. Mortality was not significantly different between the groups (p=0.056).

CONCLUSION

Low molecular weight heparin treatment is safe and provides better prognosis in MSAP.

Effects of Low Molecular Weight Heparin on Alveolar Bone Loss in Wistar Rats

This study aimed to assess the effects of low molecular weight heparin (LMWH) on alveolar bone loss (ABL), blood count, and counting of megakaryocytes and adipocytes in male Wistar rats. Forty male 60-day Wistar rats were randomly divided into four groups: Control (C), Periodontal Disease (PD), Heparin (Hp) and Heparin + Periodontal Disease (Hp+PD). LMWH was applied for 60 days at doses of 1 ml/kg/day. Blood samples were collected at baseline, 30 and 60. On day-49, PD and Hp+PD groups were subjected to ligature-induced periodontitis around second upper right molar. The left side was assessed as spontaneous alveolar bone loss. Mean ABL in the side with ligature showed significantly different between C (0.35±0.07 mm) and Hp+DP (0.49±0.09 mm) groups (p<0.001), between PD (0.55±0.11 mm) and Hp (0.32±0.06 mm) groups (p<0.001) and between Hp and Hp+DP groups (p<0.001). No significant differences were found among groups for ABL in the side without ligature. Animal weight, food intake, and water consumption showed no statistically significant difference among groups. Megakaryocytes and adipocytes were counted using optical microscopy and no statistically significant differences were found. Within-groups, there were an increase and a decrease, respectively, in the counting of lymphocytes (p=0.005 for C and p=0.009 for Hp+PD groups only) and leukocytes (p=0.003 for C, p=0.001 for PD, p=0.002 for Hp, and p<0.001 for Hp+PD groups). There was no decrease in the number of platelets in the three collection periods. LMWH was not able to affect ABL, but it may change the blood counting, especially increasing lymphocytes.

Fatal cerebral hemorrhage associated with acute pancreatitis: A case report

RATIONALE

Pancreatic encephalopathy (PE) refers to the abnormalities in mental status that complicate acute pancreatitis (AP). We report the case of a patient who developed AP that was complicated by PE and followed by fatal cerebral hemorrhage.

PATIENT CONCERNS

A 41-year-old male patient with AP that initially manifested with PE and was subsequently complicated by fatal cerebral hemorrhage.

DIAGNOSES

A head computed tomography (CT) scan showed a fatal intracerebral hemorrhage located in the occipital lobe, and an abdominal CT scan presented a large amount of peripancreatic fluid collections.

INTERVENTIONS

The patient received a hematoma evacuation. The volume of the hematoma was approximately 15 mL. A consequent open pancreatic necrosectomy was performed to remove all necrotic tissues and to drain the peripancreatic fluid collections.

OUTCOMES

The patient could perform his normal daily activities efficiently, and no abnormality was observed in the physical examination 3 months after his discharge.

LESSONS

Although uncommon, PE should be properly monitored. Once the neurological symptoms of a patient dramatically worsen within a short time, the possibility of fatal cerebral hemorrhage should be considered.

New Applications of Heparin and Other Glycosaminoglycans

Heparin, the widely used pharmaceutical anticoagulant, has been in clinical use for well over half a century. Its introduction reduced clotting risks substantially and subsequent developments, including the introduction of low-molecular-weight heparin, made possible many major surgical interventions that today make heparin an indispensable drug. There has been a recent burgeoning of interest in heparin and related glycosaminoglycan (GAG) polysaccharides, such as chondroitin sulfates, heparan sulfate, and hyaluronate, as potential agents in various applications. This ability arises mainly from the ability of GAGs to interact with, and alter the activity of, a wide range of proteins. Here, we review new developments (since 2010) in the application of heparin and related GAGs across diverse fields ranging from thrombosis and neurodegenerative disorders to microbiology and biotechnology.

Efficacy of continuous regional arterial infusion with low-molecular-weight heparin for severe acute pancreatitis in a porcine model

OBJECTIVE

Administration of heparin or its derivatives has been proved to be beneficial in the treatment of severe acute pancreatitis (SAP). However, drugs administered by conventional intravenous way are difficult to reach the pancreatic tissue and may cause bleeding complications due to coagulation and microcirculatory disturbance following initiation of SAP. In this study, we aimed to assess the effects of low-molecular-weight heparin (LMWH) administered with continuous regional arterial infusion (CRAI) technique in a porcine model of SAP.

METHODS

Following baseline measurements, 18 animals were divided into three groups: CRAI group (LMWH infused through placed arterial catheter), venous group (LMWH infused through central venous catheter), and SAP control group. We used retrograde intraductal infusion of sodium taurocholate to induce SAP. Global hemodynamic profiles, urine output, systemic oxygenation, and inflammatory and serum biochemical parameters of the animals were studied. At the end of the experiment, histological examination of pancreas, intestine, and lung was performed.

RESULTS

Continuous regional arterial infusion with LMWH remarkably stabilized hemodynamic profiles, improved systemic oxygenation and peripheral perfusion, alleviated histological injury of pancreas (especially for the necrosis scale), and downregulated inflammatory response when compared with the other two groups. Moreover, serum D-dimer level also decreased most significantly in the CRAI group (474 ± 144 vs. 664 ± 155 µg/L in the venous group and 945 ± 351 µg/L in the controls at the end), partly indicating ameliorated coagulation disorders in the study group. No bleeding complication was observed in the CRAI group, whereas two animals in the venous group presented gastrointestinal hemorrhage.

CONCLUSIONS

Continuous regional arterial infusion with LMWH exhibits strong therapeutic effects in the course of SAP with great safety. Human studies using this novel therapy are required to assess these potential benefits in the clinical setting.

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.