Especies reactivas de oxígeno en las enfermedades inflamatorias del páncreas: ¿una posible diana terapéutica?

Antioxidant and photoprotective potential of Polypodium leucotomos

In recent years, Polypodium leucotomos has emerged with a great interest for having medicinal and therapeutic potential. It is producing very promising results due to the presence of antioxidant and photoprotective properties. Electronic libraries and databases, including Scopus, PubMed, Google Scholar, Science Direct, and Web of Science were searched to identify relevant studies; 79 publications contributed to this review regarding Polypodium leucotomos botanical aspects, chemical composition, antioxidant and photoprotective activity. It is used in complementary and alternative therapies with various pharmaceutical dosage forms (systemic or topical). Thanks to the composition of phytochemical constituents present in the leaves and rhizomes which confer antioxidant and photoprotective activity that has clinical therapeutic potential to be used as systemic and topical sunscreen of natural origin for the prevention of different types of skin diseases caused by harmful ultraviolet A and ultraviolet B radiations. However, more studies are needed in the future to test the ability and enhance the capacity of sunscreen and sunblock in cosmetic formulations. To conclude, it is recommended to carry out scientific studies based on different analytical methods to evaluate the phytoconstituents potential and to develop stable pharmaceutical formulations according to the skin phototype.

Poly(ADP-ribose) polymerase inhibition modulates experimental acute necrotizing pancreatitis-induced oxidative stress, bacterial translocation and neopterin concentrations in rats

Various studies have been performed to find out novel treatment strategies for acute necrotizing pancreatitis (ANP). Inhibition of poly(ADP-ribose) polymerase (PARP) is shown to reduce inflammation in several pathological conditions. We aimed to evaluate the efficacy of benzamide, a PARP inhibitor, in an experimental model of ANP. Thirty Sprague-Dawley rats were divided into three groups: sham-operated, ANP and ANP + benzamide groups. All groups except the sham-operated group were subjected to the ANP procedure, induced by infusing of 1 mL/kg of 3% sodium taurocholate into the common biliopancreatic duct. The ANP + benzamide group received 100 mg/kg/day benzamide intraperitoneally for a total of three days after induction of pancreatitis. The surviving animals were killed at the fourth day and the pancreas was harvested for biochemical, microbiological and histological analysis. Blood samples were also obtained from the animals. In the ANP group, a significant increase was observed in concentrations of serum amylase and neopterin and tissue oxidative stress indices (malondialdehyde, superoxide dismutase and glutathione peroxidase). Almost all of these changes were found to be reversed to near their normal values in the ANP + benzamide group. Histological injury scores were significantly higher in the ANP group than in the sham group (P < 0.05, ANP versus sham), and were significantly lower in the ANP + benzamide group than in the ANP group (P < 0.05, ANP + benzamide versus ANP). Evaluation of bacterial translocation identified significantly fewer infected sites in the ANP + benzamide group than in the ANP animals (P < 0.01). We observed that inhibition of PARP with benzamide reduced the severity, the mortality, the bacterial translocation rates and the neopterin concentrations in an experimental ANP model in rats. These findings suggest that it may be possible to improve the outcome of ANP by using PARP inhibitors.

Efficacy of hyperbaric oxygen therapy and medical ozone therapy in experimental acute necrotizing pancreatitis

OBJECTIVES

Our aims were to evaluate the efficacy of ozone therapy (OT) in an experimental rat model of acute necrotizing pancreatitis (ANP) and to compare its effects with hyperbaric oxygen (HBO) therapy in this entity.

METHODS

Forty Sprague-Dawley rats were divided into sham-operated, ANP, ANP + HBO, and ANP + OT groups. Acute necrotizing pancreatitis was induced by infusing 1-mL/kg 3% sodium taurocholate into the common biliopancreatic duct. Hyperbaric oxygen was administered twice daily at a 2.8-atm pressure for 90 minutes. Ozone therapy was set as daily intraperitoneal injections of 0.7-mg/kg ozone/oxygen gas mixture. Hyperbaric oxygen and OT were continued for 3 days after the induction of ANP. The surviving animals were killed at the fourth day, and their pancreases were harvested for biochemical, microbiological, and histopathologic analyses.

RESULTS

Serum amylase/lipase and neopterin levels and tissue oxidative stress parameters were similar to sham's values in both the ANP + HBO and the ANP + OT groups. Histopathologic injury scores were significantly lower in the treatments groups than in the ANP group. When compared with the ANP group, the number of infected rats was significantly lesser in the ANP + HBO and the ANP + OT groups.

CONCLUSIONS

Hyperbaric oxygen and OT reduce the severity and the mortality in the experimental rat model of ANP, and a greater benefit was received for OT comparing with HBO.

[Inflammatory pancreatic disease due to enzyme autodigestion: an exceptional model of glandular crinophagy]

The exocrine pancreas is a functionally dangerous structure since it is exposed to digestion by its most aggressive enzymes (proteases, etc) despite self-protective measures such as the synthesis of some of these enzymes in the form of inactive zymogens (trypsinogen, etc.). We review inflammatory pancreatic disease by separately analyzing its classical forms of onset: acute and chronic pancreatitis (AP and CP). There is general consensus that the initial pathogenic event in AP is intraacinar activation of trypsinogen into trypsin, followed by that of the remaining proenzymes, giving rise to an unusual model of autophagic inflammation. In contrast, consensus is lacking on the initial pathogenic event in CP (toxic-metabolic lesion, oxidative stress, ductal hypertension, etc.?), although in some cases a <<necrosis-fibrosis>> sequence due to recurrent episodes of AP seems evident. The pathogenic features shared by both forms of the disease and which justify some recent attempts to formulate an overall explanation of the pathogenesis of pancreatitis are discussed. Such an explanation would place both forms of pancreatitis within the conceptual framework of an <<inflammatory pancreatic disease due to enzyme autodigestion>>.