Pretreatment of cisplatin in recipients attenuates post-transplantation pancreatitis in murine model

Pharmacological prevention of post-operative pancreatitis: systematic review and meta-analysis of randomized controlled trials on animal studies

BACKGROUND

Postoperative pancreatic fistula (POPF) remains a significant complication of pancreatic resection with recent evidence showing a strong association between post-operative pancreatitis and subsequent development of POPF. Incidence and severity of pancreatitis following endoscopic therapy has been effectively reduced with indomethacin prophylaxis, however further agents require evaluation. We present a systematic literature review and meta-analysis of the prophylactic treatment with corticosteroids or n-acetyl cysteine (NAC) of induced pancreatitis in rodent models.

METHODS

A systematic literature search was conducted using Pubmed, Medline, Embase and Cochrane library to identify eligible randomized control trials (RCT) involving animal models that examined NAC or corticosteroids. The primary outcome was the subsequent effect on serum amylase and IL-6 and the histopathological markers of severity such as pancreatic oedema and necrosis.

RESULTS

Four RCTs (n = 178) met inclusion criteria examining NAC and eight RCTs (n = 546) examining corticosteroid agents (dexamethasone, hydrocortisone, methylprednisolone). Prophylactic administration of all corticosteroid agents showed a net effect in favour of reducing markers of severity of pancreatitis. NAC showed a significant reduction in severity of amylase and necrosis.

CONCLUSION

The RCTs examined suggest that prophylactic administration of corticosteroid agents and NAC can reduce the severity of pancreatitis as indicated by histopathologic markers, serum amylase and IL-6 levels.

Pathophysiologic Mechanisms of Hypothermia-Induced Pancreatic Injury in a Rat Model of Body Surface Cooling

OBJECTIVE

The mechanisms underlying hypothermia-induced pancreatic injury are unclear. Thus, we investigated the pathophysiology of hypothermia-induced pancreatic injury.

METHODS

We created a normal circulatory model with body surface cooling in rats. We divided the rats into control (36°C-38°C), mild hypothermia (33°C-35°C), moderate hypothermia (30°C-32°C), and severe hypothermia (27°C-29°C) (n = 5 per group) groups. Then, we induced circulatory failure with a cooling model using high-dose inhalation anesthesia and divided the rats into control (36°C-38°C) and severe hypothermia (27°C-29°C) (n = 5 per group) groups. Serum samples were collected before the introduction of hypothermia. Serum and pancreatic tissue were collected after maintaining the target body temperature for 1 hour.

RESULTS

Hematoxylin and eosin staining of the pancreas revealed vacuoles and edema in the hypothermia group. Serum amylase (P = 0.056), lactic acid (P < 0.05), interleukin 1β (P < 0.05), interleukin 6 (P < 0.05), and tumor necrosis factor α (P = 0.13) levels were suppressed by hypothermia. The circulatory failure model exhibited pancreatic injury.

CONCLUSIONS

Hypothermia induced bilateral effects on the pancreas. Morphologically, hypothermia induced pancreatic injury based on characteristic pathology typified by vacuoles. Serologically, hypothermia induced protective effects on the pancreas by suppressing amylase and inflammatory cytokine levels.

E-cadherin expression in a rat model of acute pancreatitis

A clinical requirement exists for early biomarkers that can predict the severity of acute pancreatitis (AP). In order to determine whether E-cadherin is associated with the severity of AP, a pancreatitic rat model was established and the expression levels of E-cadherin were detected. A study population of 24 Sprague Dawley rats was administered intraperitoneal injections of various concentrations of L-arginine in order to induce pancreatitis. Rats were assigned to the severe acute pancreatitis (SAP) or mild acute pancreatitis (MAP) group based on the results of histological evaluations and the serum levels of amylase. An additional 8 rats received intraperitoneal injections of NaCl solution, as a control group. For each group, the serum concentrations of soluble E-cadherin and the expression levels of E-cadherin protein in the pancreatic tissue were detected. The results indicated that the rat model of pancreatitis was successfully established. Rats in the high concentration L-arginine treatment group, which exhibited a higher pancreatitis pathology score and level of serum amylase, were assigned to the SAP group. Low concentration L-arginine group rats were assigned to the MAP group. The pathology scores and levels of serum amylase in the SAP and MAP group rats were higher compared with the control group rats. The levels of serum E-cadherin were the most elevated in the SAP group. Statistically significant differences were detected in the SAP and MAP groups compared with the control group, and in the SAP group compared with the MAP group (P<0.05). Furthermore, the levels of E-cadherin protein in the pancreatic tissue were elevated in the SAP group compared with the MAP and control groups. In conclusion, the present study demonstrated that E-cadherin was overexpressed in SAP rats, and the overexpression of E-cadherin may be associated with the severity of AP.

HMGB1 in health and disease

Complex genetic and physiological variations as well as environmental factors that drive emergence of chromosomal instability, development of unscheduled cell death, skewed differentiation, and altered metabolism are central to the pathogenesis of human diseases and disorders. Understanding the molecular bases for these processes is important for the development of new diagnostic biomarkers, and for identifying new therapeutic targets. In 1973, a group of non-histone nuclear proteins with high electrophoretic mobility was discovered and termed high-mobility group (HMG) proteins. The HMG proteins include three superfamilies termed HMGB, HMGN, and HMGA. High-mobility group box 1 (HMGB1), the most abundant and well-studied HMG protein, senses and coordinates the cellular stress response and plays a critical role not only inside of the cell as a DNA chaperone, chromosome guardian, autophagy sustainer, and protector from apoptotic cell death, but also outside the cell as the prototypic damage associated molecular pattern molecule (DAMP). This DAMP, in conjunction with other factors, thus has cytokine, chemokine, and growth factor activity, orchestrating the inflammatory and immune response. All of these characteristics make HMGB1 a critical molecular target in multiple human diseases including infectious diseases, ischemia, immune disorders, neurodegenerative diseases, metabolic disorders, and cancer. Indeed, a number of emergent strategies have been used to inhibit HMGB1 expression, release, and activity in vitro and in vivo. These include antibodies, peptide inhibitors, RNAi, anti-coagulants, endogenous hormones, various chemical compounds, HMGB1-receptor and signaling pathway inhibition, artificial DNAs, physical strategies including vagus nerve stimulation and other surgical approaches. Future work further investigating the details of HMGB1 localization, structure, post-translational modification, and identification of additional partners will undoubtedly uncover additional secrets regarding HMGB1's multiple functions.

Cisplatin protects against acute liver failure by inhibiting nuclear HMGB1 release

Cisplatin is one of the most widely used chemical drugs for anticancer treatment. Recent studies have focused on the ability of cisplatin to retain the high mobility group box 1 (HMGB1) protein in cisplatin-DNA adducts, thereby preventing its release from the nucleus. Because HMGB1 is a powerful inflammatory mediator in many diseases, the aim of this study is to evaluate the therapeutic effect of cisplatin acute liver failure. In this study, low-dose cisplatin was administered to treat PMA-induced macrophage-like cells induced by PMA and rats with acute liver failure. We found that cell viability and liver injury were greatly improved by cisplatin treatment. The extracellular levels of HMGB1, TNF-α and IFN-γ were also significantly decreased by the administration of cisplatin. During inflammation, nuclear HMGB1 translocates from the nucleus to the cytoplasm. The administration of cisplatin reduced the cytoplasmic levels of HMGB1 and increased nuclear HMGB1 levels in vitro and in vivo. In conclusion, cisplatin can protect against acute liver failure by retaining HMGB1 in the nucleus and preventing its release into the extracellular milieu.