Evaluation of circulating miR-216a and miR-217 as biomarkers of pancreatic damage in the L-arginine-induced acute pancreatitis mouse model

We investigated the usefulness of circulating miR-216a-5p and miR-217-5p that are pancreas-enriched micro RNAs (miRNAs) as biomarkers of acute pancreatic damage, and compared them with conventional pancreatic biomarkers in L-arginine-induced acute pancreatitis mouse model. As the results, amylase and lipase levels apparently increased and peaked on Day 3 when acute pancreatitis including acinar cell degeneration/necrosis and inflammatory cell infiltration reached its peak. In contrast, miR-216a-5p and miR-217-5p increased from Day 1 when histopathological findings in the acinar cells were limited to decreased zymogen granules, and the increases in ratios were much higher than those of amylase and lipase. The miRNAs remained at high levels until Day 5 when the pseudo-tubular complex and replacement of inflammatory cells and fibrotic cells were apparent instead of necrosis, whereas amylase and lipase levels decreased to the control levels. Furthermore, we examined the relationship between biomarker levels and histopathological degeneration/necrosis scores in the acinar cells. miR-216a-5p and miR-217-5p levels increased depending on the score of degeneration/necrosis, and all individual miRNAs exceeded the control levels from a score of 2 (focal necrosis), whereas all individual amylase and lipase levels exceeded the control levels at scores of 4 (lobular necrosis) and 3 (sublobular necrosis), respectively. In conclusion, we demonstrated that circulating miR-216a-5p and miR-217-5p could detect pancreatic damage earlier with greater magnitude, and the sensitivity to detect acinar cell degeneration/necrosis was superior to that of conventional biomarkers in the L-arginine-induced acute pancreatitis mouse model.

Safety evaluation of a lipase enzyme preparation, expressed in Pichia pastoris, intended for use in the degumming of edible vegetable oil

BD16449 lipase is the product of a phospholipid-specific lipase gene expressed in the yeast Pichia pastoris strain DVSA-PLC-004. This type C phospholipid lipase (EC 3.1.4.3) is intended for use in the degumming of edible vegetable oil. BD16449 lipase was tested as a refined test article preparation (DV16449) for its effects on genotoxicity and in acute, inhalation, and subchronic toxicity studies. Dosages ranged from 5000 microg/plate for in vitro toxicity studies to 2000 mg/kg/day for in vivo toxicity studies. The highest oral dose tested in vivo (NOAEL of 2000 mg/kg/day) resulted in a safety margin of 133,000 based on the conservative estimate of the total human consumption of BD16449 lipase of 0.015 mg/kg/day. When adjusted for total organic solids (TOS), the highest oral dose tested in vivo (NOAEL of 1680 mg TOS/kg/day) resulted in a safety margin of 18,300 based on the conservative estimate of the total human consumption of BD16449 lipase of 0.092 mg TOS/kg/day [corrected] There was no toxicity reported for any of these studies including additional safety studies. A review of the literature indicates that P. pastoris fulfills recognized safety criteria pertinent to microbial production strains used in the manufacture of food enzyme preparations. The results of the toxicity studies presented herein attest to the safety of BD16449 lipase for use in the degumming of edible vegetable oil.

Occupational asthma caused by cellulase and lipase in the detergent industry

Three employees from two different detergent companies were investigated for occupational asthma, using skin prick tests, serum specific IgE, and specific bronchial challenge. Two were challenged with lipase and one with cellulase. All three cases had immunological evidence of sensitisation to the detergent enzymes with which they worked. Bronchial challenge in each provoked a reproducible dual asthmatic response, which reproduced their work related symptoms. These are the first reported cases of occupational asthma attributable to cellulase and lipase in the detergent industry. Four of the most common enzymes used in this industry have now been reported to cause occupational asthma; continued vigilance and caution are needed when working with these or other enzymes.

Safety evaluation of lipase produced from Rhizopus oryzae: summary of toxicological data

The toxicity of Lipase D, an enzyme preparation, was evaluated in a series of studies. Lipase D selectively hydrolyzes triglycerides of fatty acids. It also catalyzes the interesterification of edible fats and oils. In a 13-week gavage study, Sprague-Dawley rats received Lipase D at levels of 0, 500, 1000, or 2000 mg/kg body wt./day. A dose dependent decrease in urinary pH was observed, but there were no effects on electrolyte balance, kidney weight, or histology of the kidney. The no-observed-adverse-effect level in rats was 1000 mg/kg body wt./day. In common with other enzyme preparations, Lipase D was not genotoxic. Lipase D was tested in the Ames assay, the mouse lymphoma forward mutation assay, and the chromosome aberration assay. Finally, the particular strain of Rhizopus oryzae used to prepare Lipase D was shown to have low to moderate pathogenicity when injected into the tail vein of mice at doses up to 1.3 x 10(6) colony-forming units (CFU) per animal. No effects were observed when mice received up to 2.2 x 10(5) CFU by gavage or in their diets daily for 28 days. The results indicate that this particular strain can be handled using ordinary safety practices current in the fermentation industry. These studies support a conclusion that Lipase D is safe when used as described in the processing of dietary fatty acids and glycerides of fatty acids.

Safety Evaluation of Lipase Produced from Candida rugosa: Summary of Toxicological Data

The toxicity of lipase AY, an enzyme preparation used in lipid hydrolysis to produce flavors, was evaluated in a series of studies. A 13-week dietary toxicity study in Sprague-Dawley (Crj:CD) rats was conducted in which animals received lipase AY in the feed at concentrations of 0, 625, 1250, or 2500 mg/kg body wt. No adverse treatment-related effects were observed. Lack of genotoxic potential was demonstrated by the results of an in vitro reverse mutation assay in Salmonella typhimurium strains TA98, TA100, TA1535, and TA1537 and in Escherichia coli strain WP2 uvrA, by an in vitro forward mutation assay in L5178Y mouse lymphoma cells, and by an in vitro chromosome aberration test in CHL/IU cells derived from fibroblasts of the lungs of Chinese hamsters. Finally, the particular strain of Candida rugosa, the yeast strain used to prepare lipase AY, has been shown to be nonpathogenic upon a single injection into the tail vein of rats of viable spores at doses up to 1.5x10(7) colony-forming units per animal. The results of these studies demonstrate that the enzyme preparation may be considered safe to workers and consumers when employed in the production of flavors from fats.

Safety evaluation of lipase derived from Rhizopus oryzae: summary of toxicological data

A lipase enzyme, obtained from Rhizopus oryzae produced by a fermentation process was subjected to a series of toxicological tests to document the safety for use as a food additive. The enzyme product was examined for acute, subacute and subchronic oral toxicity, and mutagenic potential. An extensive literature search on the production organism has also been conducted. No evidence of (sub)acute oral toxicity or mutagenic potential was found. Administration of the lipase at dosages of 50, 200 and 1000 mg/kg body weight/day for 90 days did not induce noticeable signs of toxicity. A few minor changes in the chemical composition of the blood in the highest dose group were of no toxicological significance. The no-observed-adverse-effect level of the tox-batch in the subchronic toxicity study was 1000 mg/kg body weight/day. It can be concluded that no safety concerns were identified in the studies conducted with this lipase preparation derived from R. oryzae and produced under controlled fermentation conditions.

An experimental model of fasciitis-panniculitis. Induction of chronic fibrosing panniculitis in the rat by subcutaneous injections of lipase

We describe an experimental model of the fasciitis-panniculitis syndrome, which includes eosinophilic fasciitis and its related disorders. Rats were given a single or repeated subcutaneous injections of saline or a 10% lipase solution. The injection sites were studied histologically and histomorphometrically. With few exceptions, the subcutaneous-fascial unit of the saline-injected rats was normal. An acute necrotizing panniculitis with inflammatory involvement of the adjacent fascia was found 2 days after a single injection of lipase. Three to 6 weeks after a single injection of lipase, the subcutaneous fat tissue and fascia were fibrotically thickened and chronically inflamed. Similar but more advanced alterations had developed in animals killed 3 weeks after three weekly injections of lipase. Progressive fibrotic thickening of the subcutaneous-fascial unit was observed following an increasing number of weekly lipase injections. The acute-phase reaction expresses a pattern of steatonecrotic tissue damage. In the ohronic phase, the fibrotically thickened subcutaneous layers typify a reaction pattern analogous to that of the human fasciitis-panniculitis syndrome. This experimental model permits better appreciation of the disorder's nonspecific pathogenesis and may help in the search for alternative therapeutic modalities.

Safety evaluation of a lipase expressed in Aspergillus oryzae

A programme of studies was conducted to establish the safety of a lipase artificially expressed in Aspergillus oryzae to be used in the detergent industry and as a processing aid in the baking industry. Laboratory animal studies were used to assess general and inhalation toxicity, skin sensitization, and skin and eye irritation. Its potential to cause mutagenicity and chromosomal aberrations was assessed in microbial and tissue culture in vitro studies. The pathogenicity of A. oryzae, the organism used to produce the lipase, was also assessed in laboratory animals. Basic ecotoxicity in a variety of test species was studied. General and inhalation toxicity was low. There was evidence of mild skin irritation. There was no evidence of eye irritation, skin sensitization, mutagenic potential, chromosomal aberrations, exotoxicity or notable pathogenicity. Comparison of these results with human exposure levels and previously published data indicates that the lipase appears safe for consumers in the given applications, requires no special occupational health precautions in manufacture and is of low environmental impact. Furthermore, the organism used in production of the lipase hs no notable pathogenicity.

Safety evaluation of lipase G from Penicillium camembertii

Lipase G, a partial glycerides eliminating enzyme produced by Penicillium camembertii, was subjected to safety evaluation studies to establish its safety when used as a processing aid in the food industry. The toxicological studies on the enzyme included a 90-day gavage study with rats, a mutagenicity study using bacteria, and a pathogenicity study using mice. The no-adverse-effect level from the 90-day gavage toxicity study was 2000 mg/kg body weight/day for rats. There was no evidence of mutagenic potential. The micro-organism was evaluated for pathogenicity using mice and classified as a non-pathogen. Results indicate that the production and use of lipase G may be regarded as safe for the enzyme production worker and the consumer.

An overview of the safety evaluation of the Rhizomucor miehei lipase enzyme

The Rhizomucor miehei lipase enzyme expressed in Aspergillus oryzae, is used in the production of specialty fats, the production of existing fats from new raw materials, or new fats with improved nutritional or functional qualities. It is produced by A. oryzae containing the structural gene for the precursor of R. miehei triglyceride lipase. It was subjected to a series of toxicological tests to document the safety in use. The enzyme preparation was not found to be mutagenic either in bacterial cultures (Ames test) or in the mammalian cell cultures (mouse lymphoma assay), nor did it cause chromosomal damage (human lymphocyte assay). Dietary concentrations up to 1600 mg/kg diet for up to 13 weeks caused no adverse effect in rats. At higher concentrations there were effects upon food intake, possibly arising from some irritant property of the enzyme preparation in the diet at such high levels, with consequential effects upon bodyweight and energy metabolism. A minor effect upon renal function was indicated by increased kidney weight and changes in the urine. At 40,000 mg/kg diet the enzyme was considered to have exacerbated the onset of normally-occurring chronic myocarditis in male Sprague-Dawley rats.

The effects of purified 25-kDa lipase from a clinical isolate of Pseudomonas cepacia in the lungs of rats

Nanogram quantities of a 25-kDa lipase purified from culture supernatants of Pseudomonas cepacia 90ee, a sputum isolate from a cystic fibrosis (CF) patient, were placed in the lungs of healthy rats. The resulting pathological changes included large amounts of proteinaceous exudate, the accumulation of polymorphonuclear leukocytes and red blood cells, and disorganization of alveolar structure. Pseudomonas cepacia 90ee immobilized in agar beads was also placed in the lungs of rats in a model of chronic infection. This resulted in bronchopneumonia and a milder inflammatory response than that elicited by the purified enzyme.

Production of lipase by clinical isolates of Pseudomonas cepacia

Ten clinical isolates of Pseudomonas cepacia from the sputum of cystic fibrosis patients were examined for the ability to produce lipase. Lipase substrates used included egg yolk agar, four different polyoxyethylene sorbitans (Tweens), and p-nitrophenylphosphorylcholine, a chromogenic substrate used to assay for phospholipase C. Lipase activity was detected in the filtrates of organisms grown to the exponential phase in either tryptose minimal medium or chemically defined medium. Lipase activity increased in the filtrates if the cultures were allowed to proceed into the stationary phase. None of the isolates produced phospholipase C. Lipase activity on Tween 20 ranged from 41.6 X 10(-3) to 640.0 X 10(-3) U/micrograms of protein. The activity was similar or slightly lower when Tween 40, 60, or 80 was used as the substrate. There was no correlation between lipase activity on Tween and that demonstrated on egg yolk agar. Lipase activity increased as pH increased from 7.0 to 9.0. Boiling for 5 min resulted in 66% loss of enzyme activity. The remaining activity continued to decrease with increasing boiling time. The enzyme was purified by gel filtration on Sephadex G-200, and the resultant preparation, when subjected to polyacrylamide gel electrophoresis, resulted in a single protein band (molecular weight, approximately 25,000) from which lipase activity could be eluted. The purified lipase was not cytotoxic to HeLa cells, nor was it toxic when injected intravenously into mice.