Octreotide ameliorates hypoxia/reoxygenation-induced cerebral infarction by inhibiting oxidative stress, inflammation and apoptosis, and via inhibition of TLR4/MyD88/NF-κB signaling pathway

Purpose: To explore the effects of octreotide (OCT) on oxidative stress, inflammation and apoptosis in hypoxia/reoxygenation (H/R)-induced cerebral infarction.Methods: The in vitro model of cerebral infarction was established by treating N2A cells with hypoxia for 4 h and reoxygenation for 24 h. The viability of N2A cells was determined by CCK-8 assay. The cells were divided into 3 groups: control group, H/R group, and H/R+OCT group. The cells in H/R+OCT group were pretreated with OCT (60 ng/mL) before H/R treatment. The oxidative stress of N2A cells were assessed by determining the levels of superoxide dismutase (SOD), glutathione peroxidase (GSHPx), catalase (CAT), reactive oxygen species (ROS) and malondialdehyde (MDA). Inflammation of N2A cells was evaluated by evaluating the levels of TNF-α, IL-1β, IL-6, and IL-8, while the apoptosis of N2A cells was assessed by flow cytometry. Western blot analysis was used to determine the expression of Bcl-2, Bax, TLR4, MyD88, and NF-κB.Results: Octreotide treatment significantly reduced the level of oxidative stress. The inflammation of N2A cells caused by hypoxia/reoxygenation was inhibited by treatment with octreotide. Apoptosis of N2A cells was also inhibited by octreotide treatment. Hypoxia/reoxygenation activated TLR4/MyD88/NF-κB signaling pathway, while octreotide inhibits the activation of this pathway.Conclusion: The results reveal that octreotide inhibits hypoxia/reoxygenation-induced oxidative stress,as well as the inflammation, and apoptosis of N2A cells by inhibiting TLR4/MyD88/NF-κB signaling pathway. Thus, these findings may provide new insights into the treatment of cerebral infarction.

The use of high dose octreotide in management of neonatal chylothorax: Review

BACKGROUND: Being a rare condition, the incidence of chylothorax among neonates is low, but the mortality rate is high. In a dire effort to reduce the risk of death, octreotide treatment is used to effectively treat acquired and congenital chylothorax. Octreotide is proven to effectively treat chylothorax in pre-term and full-term neonates. However, previous studies have not consistently demonstrated the optimal dose of octreotide or the best mode of administration. The objectives of this work were to review previous literature to determine the outcomes of administering high doses of octreotide compared to lower dose regimens in neonates with chylothorax and to determine best practices. METHODS: A literature search was performed using electronic databases using the key words neonates, chylothorax, and octreotide. RESULTS: Octreotide has been administrated in doses ranging from 0.5μg/kg/h to > 20μg/kg/h. Both low- and high-doses of octreotide are effective in resolving chylothorax with little to no side effects. When side effects were reported, neonates experienced side effects that are less significant in nature and scope. CONCLUSIONS: We recommend that the dose of octreotide in neonatal chylothorax can be titrated safely to a maximum of 20μg/kg/h without significant side effects.

Impact of pasireotide on postoperative pancreatic fistulas following distal resections

Purpose Postoperative pancreatic fistula (POPF), a difficult complication after surgery, can cause peripancreatic fluid collection and infections in the operative area. In addition, pancreatic fluid is corrosive and can lead to postoperative bleeding. Clinically significant grade B and C fistulas (CR-POPF) increase postoperative morbidity, resulting in a prolonged hospital stay. Delaying adjuvant therapy due to fistula formation in cancer patients can affect their prognosis. In this study, we aimed to determine if pasireotide affects fistula formation, and the severity of other complications in patients following pancreatic distal resections. Data and methods Between 2000 and 2016, 258 distal pancreatectomies were performed at Helsinki University Hospital and were included in our analysis. Pasireotide was administered to patients undergoing distal resections between July 2014 and December 2016. Patients received 900-μg pasireotide administered twice daily perioperatively. Other patients who received octreotide treatment were analyzed separately. Complications such as fistulas (POPF), delayed gastric emptying (DGE), postpancreatectomy hemorrhage (PPH), reoperations, and mortality were recorded and analyzed 90 days postoperatively. Results Overall, 47 (18%) patients received pasireotide and 31 (12%) octreotide, while 180 patients (70%) who received neither constituted the control group. There were 40 (16%) clinically relevant grade B and C POPFs: seven (15%) in the pasireotide group, three (10%) in the octreotide group, and 30 (17%) in the control group (p = 0.739). Severe complications categorized as Clavien–Dindo grade III or IV were recorded in 64 (25%) patients: 17 (27%) in the pasireotide group, 4 (6%) in the octreotide group, and 43 (67%) in the control group (p = 0.059). We found no 90-day mortality. Conclusions In this study, pasireotide did not reduce clinically relevant POPFs or severe complications following pancreatic distal resection.

Protective Effect of Octreotide Against Liver Ischemic Reperfusion Injury in Rats

Liver ischemia-reperfusion injury (LIRI) is an inevitable complication during liver resection and liver transplantation. This study explored the effect of octreotide pretreatment on LIRI in rat model. Thirty male SD rats were included. They were divided into three groups: control group (sham operation plus saline treatment); ischemia/reperfusion group (IR group, ischemia/reperfusion operation plus saline treatment) and octreotide treatment group (IR + Oct group, ischemia/reperfusion operation plus octreotide treatment). The serum liver enzymes (ALT, AST) were tested to assess the liver damage in the rats. Light and electron microscopy was used to identify morphological alterations in each group. The expressions of HMGB1, RIP1 and RIP3 were measured by Immunohistochemistry and Western Blot. The levels of AST, ALT in IR group increased significantly (P < 0 05), and were significantly reduced by Octreotide pretreatment (P < 0 05). Morphology of control group remained grossly normal by transmission electron microscopy. While mitochondrial degeneration, cristae disruption, swelling, rupture was observed in IR group. The microscopic morphology of liver cells was basically normal and occasionally a small number of mitochondria were a little swelled in pretreatment with octreotide group. The expressions of HMGB1, RIP1 and RIP3 in pretreatment with octreotide were significantly down-regulated compared with those in pretreatment without octreotide (P < 0 001). The present study suggested that octreotide pretreatment play a protective role in LIRI, due to the decreased necrotizing apoptosis of hepatocytes. The mechanisms underlying these effects may be associated with the inhibition of HMGB1/RIP1/RIP3 necrotizing apoptosis signals.

Octreotide Reduces Pancreatic Islet Apoptosis and Improves Islet Transplantation Efficiency In Vitro and In Vivo

The drug octreotide, a somatostatin analog, stimulates the cellular free radical scavenging system and inhibits the release of superoxide anions from monocytes. We hypothesized that octreotide also protects islet β cell function and improves the survival of transplanted islets by ameliorating the adverse effects of hypoxia and reoxygenation on these cells, thus inhibiting apoptosis. To test this hypothesis, we experimentally induced hypoxia in islet cells in mouse insulinoma Min6 cells. Octreotide treatment mildly but significantly improved cell viability under normoxic and hypoxic conditions. Secreted vascular endothelial growth factor (VEGF) from the Min6 cells was downregulated after octreotide treatment during hypoxia. By contrast, the expression of hypoxia-inducible factor (HIF)-1α was upregulated after octreotide treatment under both normoxic and hypoxic conditions. Octreotide treatment also lowered the apoptotic rate of Min6 cells under hypoxic conditions in vitro. In a mouse transplant model, octreotide improved the post-transplantation efficacy and function of islet grafts. Expression of p53 and Bax in islet grafts was upregulated in the recipients treated with octreotide one day after islet transplantation, and the octreotide-treated group produced significantly less Bax than the control group on days 3 and 7 following transplantation. TUNEL assay further demonstrated a decrease in islet cell apoptosis in the octreotide group on days 1, 3, 7, and 14 after transplantation compared with that of the control group (P < 0.05). No islet cell proliferation was found in the octreotide and control groups on days 1, 3, and 7 following transplantation. However, by day 14, the group treated with octreotide demonstrated significantly higher average cell proliferation rates than the controls did (P < 0.05). Thus, octreotide decreased the apoptosis of islets under hypoxic conditions in vitro and enhanced the efficacy of islet transplantation in vivo. Octreotide has excellent potential for therapeutic applications in islet transplantation and merits further study.