Halloysite nanotube-embedded microparticles for intestine-targeted co-delivery of biopharmaceuticals.

Microparticles (MPs) with pH-responding macropores have recently proved their significance for the delivery of vulnerable biomolecules for oral drug administration. The previous MP systems were proven to provide enhanced protection against the gastric environment, however, their application is hindered due to insufficient loading efficiencies and deficient penetration capabilities of encapsulated drugs across the mucus barrier. Here, we report a new co-delivery approach based on amine-functionalized halloysite nanotube (HNT)-embedded MPs (amine-HNT-MPs) with pH-responding macropores specifically designed to deal with the mucus barrier at the absorption site. The mean diameter and polydispersity index of the pored MPs were measured by a particle size analyzer to be 37.6 ± 1.3 µm and 1.15, respectively. The drug loading capacity of the co-delivery system was shown to be 50-times higher than previously reported pored MPs. Fluorescence microscopy analysis of sulforhodamine B (into a hollow interior of HNTs)/ fluorescent nanoparticles (into a hollow interior of MPs)-encapsulated MPs confirmed biphasic release behavior due to pH-dependent pore closing/opening in the simulated gastrointestinal (GI) digestive conditions. To verify the protective effect of the co-delivery system, bromelain and lactase were loaded into HNTs and MPs, respectively, and found to exhibit 94.5 ± 3.3% (bromelain) and 70 ± 14.1% (lactase) functional activity in simulated GI tract conditions. The considerable improvement in the stability of the encapsulated enzymes against gastric conditions are attributed to the efficient pore sealing of the co-delivery system after the encapsulation of enzymes and maintenance of these closed pores in the gastric environment. Furthermore, the mucolytic enzyme (i.e. bromelain)-encapsulated co-delivery system was found to enhance mucopenetration of the encapsulated drug from histological analysis using ex vivo porcine intestine tissue. Therefore, the new microencapsulation design proposed in this study provides a promising solution to the major issues hampering the wide-spread application of MPs in the development of oral drug formulations for biopharmaceuticals and vaccines.

Efficacy of proteolytic enzyme bromelain on health outcomes after third molar surgery. Systematic review and meta-analysis of randomized clinical trials

Background: Bromelain is a cysteine protease isolated from pineapple with a range of biological properties including platelet aggregation inhibition and anti-inflammatory effects. Recent studies have evaluated the clinical implications of bromelain in reducing postoperative inflammatory complications after third molar surgery, but the results are contrasting. This systematic review and meta-analysis evaluated the effects of bromelain on health outcomes in patients submitted to third molar surgery. Material and methods: The study was conducted following the PRISMA statement. Searches were conducted in six electronic databases and Google Scholar from inception to May 2018. The following elements were used to define eligibility criteria: (1) population: patients undergoing third molar surgery; (2) intervention and controls: bromelain vs placebo or no-treatment control group; (3) outcomes: quality of life, postoperative pain, rescue analgesic consumption, facial swelling, and trismus; and (4) study type: randomized clinical trials (RCTs). Treatment effects were defined as weighted (WMD) or standardized mean difference (SMD) and 95%CIs. Results: Six RCTs were included in the meta-analysis. There was large effect size of bromelain on improving physical appearance (SMD -0.77, CI% 95 -1.11 to -0.42), social isolation (SMD -0.97, CI% 95 -1.74 to -0.21), and sleep quality (SMD -1.19, CI% 95 -1.97 to -0.40) during the first postoperative week. Differences in pain intensity were found during the first 24h (SMD -0.49, CI 95% -0.82 to -0.17) and 7 days after surgery (SMD -0.52, CI 95% -0.79 to -0.24). No evidence was found that bromelain was effective in reducing trismus and facial swelling. Conclusions: The currently available evidence suggests that bromelain has a beneficial effect in reducing pain and has a positive impact on patient quality of life after third molar surgery. However, therapeutic advances for the use of bromelain need a high level of evidence and further head-to-head RCTs are needed to inform clinical choices

No disponible

Bromelain's penetration into the blood and sinonasal mucosa in patients with chronic rhinosinusitis.

SUMMARY: The aim of this research is to investigate penetration of Bromelain into sinonasal mucosa in patients with chronic rhinosinusitis (CRS) versus a control group. Bromelain is derived from pineapple (Ananas comosus) and has various pharmacological effects. 40 patients (20 patients and 20 controls) were enrolled in the study. Bromelain 500 mg tablet twice daily was administered for 30 days. We scored bromelain presence in turbinate and ethmoid mucosas and in the serum of both the groups. Bromelain has an excellent distribution from blood to rhinosinusal mucosa. Its diffusion ability may allow the use of bromelain as an anti-inflammatory agent in paranasal sinus pathologies.

Effect of Supplementary Administration of Anaheal on Reducing Pain, Swelling and Trismus after Mandibular Third Molar Surgery: A Splitmouth Controlled Randomized Clinical Trial

Objective: To evaluate the effect of supplementary administration of Anaheal capsule in reducing pain, swelling and trismus after surgical removal of impacted mandibular third molars. Material and Methods: This single-blind controlled randomized clinical trial was conducted on 36 patients referring to Tabriz University of Medical Sciences. Each of the 36 patients had bilateral surgical removal of mandibular third molars in two sessions, with at least a 4-week interval between sessions. In the same individual, one of the sites randomly received a test medication whereas the other site was used as a control. In the test subgroup (test medication side), the first dose of Anaheal capsule was given as a 200-mg dose of bromelain immediately after surgery according to manufacturer's instructions and the subsequent doses were given at 6-hour intervals after the first dose. The medication was administrated for 3 days. In the control subgroup (control side), Anaheal was not administered. The severities of pain, swelling and maximum mouth opening (MMO) were recorded one and three days postoperatively. Paired t-test and t-test for independent samples were used. Statistical significance was defined at p<0.05. Results: A total of 72 surgical extractions were performed; 36 procedures served as control and 36 cases received Anaheal. Pain, swelling and trismus of the patients were at the highest levels one day after surgery, which decreased on day 3. However, independent t-test showed no significant differences in pain, swelling and trismus after surgery between the study subgroups (p>0.05). Conclusion: Supplementary administration of Anaheal (800 mg bromelain daily) had no significant effect on decreasing pain, swelling and trismus at 1- and 3-day intervals after surgical removal of mandibular third molars.

Prospective double-blind clinical trial evaluating the effectiveness of Bromelain in the third molar extraction postoperative period

OBJECTIVES: To evaluate the anti-inflammatory and analgesic effect of Bromelain (pineapple extract) administered orally in the postoperative after extraction of impacted lower molars. Study DESIGN: This is a prospective, placebo-controlled, unicentric, double-blind study; the sample size was 34 patients. The pre and postoperative outcomes, evaluated on the third (D3) and eighth day (D8), included inflamtion, pain and oral aperture, as well as the need for analgesics. One group received Bromelain 150mg per day for three days and 100mg on days 4 to 7. The other group received placebo in the same dosage. All outcomes werrecorded quantitatively and analyzed with the Mann-Whitney U test for independent samples. RESULTS: Although there were no statistically significant differences between the treatment groups, a trend towards less inflammation and improved oral aperture was observed in the group that received Bromelain, compared to the group that received placebo. This trend can be attributed completely to random reasons, since there is no statistical difference in the results. CONCLUSIONS: Further studies are necessary to analyze different administration patterns and doses of Bromelain for the use in the postoperative of impacted third molars

Specific molten globule conformation of stem bromelain at alkaline pH.

Stem bromelain (SBM), a therapeutic protein, is rapidly absorbed across the gut epithelium. Because SBM encounters an alkaline pH at its principal site of absorption, we investigated the alkaline-induced denaturation of SBM. From pH 7 to 10, the protein's secondary structure remained the same, although a slight loss of tertiary structure was observed. Above pH 10, there was a significant and irreversible loss of secondary and tertiary structure. At pH 10, SBM showed enhanced tryptophan fluorescence, however, the number of accessible tryptophans remained the same. The thermodynamics of temperature transition at pH 7 and 10 were strikingly different, with the former showing a two-phase transition endotherm, and the latter a broad non-two-state transition. At pH 10, SBM showed a significant increase in 8-anilino-1-naphthalene-sulfonate binding relative to the native state, suggestive of a specific molten globule (SMG) state. These studies suggest a distinct conformational rearrangement in SBM, at the protein's isoelectric point.

Proteolytic activity and immunogenicity of oral bromelain within the gastrointestinal tract of mice.

Bromelain is a mixture of proteinases derived from pineapple stem that is marketed by health food stores as a "digestive aid". A number of studies suggest that bromelain may also have anti-inflammatory activity in vivo, including an anecdotal report describing potential efficacy in inflammatory bowel disease. We and others have previously shown that proteolytically active bromelain removes certain cell surface molecules and affects leukocyte migration, activation, and production of cytokines and inflammatory mediators in vitro. The purpose of this study was to determine whether ingested bromelain retains proteolytic activity within the murine gastrointestinal tract in vivo. The proteolytic activity of bromelain was determined in vitro using model substrates or immunofluorescence assays after administration of various doses and formulations orally to mice. Immune responses against bromelain were detected by enzyme immunoassays. When formulated in antacid, oral bromelain retained substantial proteolytic activity throughout the gastrointestinal tract. Bromelain concentrations within the colon were dependent on both dose and formulation and were sufficient to remove bromelain-sensitive molecules from both leukocytes and colon epithelial cells. Peak activity in the stool was observed 4 h after oral dosing. Although anti-bromelain IgG was detected in both serum and stool after long-term oral therapy, these antibodies did not prevent bromelain proteolytic activity within the gastrointestinal tract. These studies demonstrate that bromelain enzymes can remain intact and proteolytically active within the murine gastrointestinal tract. They provide further support for the hypothesis that oral bromelain may potentially modify inflammation within the gastrointestinal tract via local proteolytic activity within the colonic microenvironment.

Peroral administration of enzymes: strategies to improve the galenic of dosage forms for trypsin and bromelain.

In this study, we investigated the presystemic metabolism of trypsin and bromelain and the influence of these proteolytic enzymes on the mucus layer covering the gastrointestinal (GI) epithelia. In vitro studies demonstrated that 77.3% +/- 4.0% (mean +/- SD, n = 3) of trypsin is autodegraded within 2 hr, whereas autodegradation of bromelain was negligible. In contrast to the metabolization of bromelain by all pancreatic serine proteases, trypsin is only degraded to some extent by elastase. Both therapeutically used enzymes remained stable after incubation with an excised porcine mucosa, demonstrating that proteolysis caused by brush border membrane-bound enzymes is negligible. Trypsin and bromelain were highly mucolytic active, thereby reducing the diffusion barrier based on the mucus gel layer. Strategies to improve the galenic of dosage forms for trypsin and bromelain include the use of bioadhesive polymers such as hydroxyethylcellulose or slightly modified chitosan-EDTA, providing strongly improved stability of these enzymes toward proteolytic degradation in vitro. The given information represents a good starting point to improve the galenic of dosage forms for orally administered proteolytic enzymes.

Intestinal absorption of undegraded proteins in men: presence of bromelain in plasma after oral intake.

The human adult intestinal epithelium has traditionally been described as nonpermeable to proteins. However, indirect evidence suggests that reduced absorption of undegraded proteins might take place under physiological conditions. Using bromelain (an enzyme obtained from pineapple stems) as a model protein, we studied the extent of this mucosal permeation in 19 healthy men. The protein was detected in plasma by immunoassay and by its proteolytic activity after oral administration. The estimated plasma half-life was 6-9 h. After oral multidosing (3 g/day), plasma concentration reached as much as 5,000 pg/ml by 48 h. From the plasma concentration curve, it could be estimated that an average of 10.8 micrograms of bromelain was present in plasma in the 3- to 51-h period. The presence of undegraded bromelain in plasma was shown unequivocally by immunoprecipitation of plasma samples with antibromelain antibodies, followed by gel electrophoresis and immunodetection. Moreover, the enzyme retained its biological activity, at least in part. Circulating bromelain was found associated with alpha 2-macroglobulin and alpha 1-antichymotrypain. The results of this work confirm the existence of a small but significant intestinal transport of undegraded proteins in healthy men.

On the pharmacology of bromelain: an update with special regard to animal studies on dose-dependent effects.

Bromelain, a standardized complex of proteases from the pineapple plant, is absorbed unchanged from the intestine of animals at a rate of 40%; in animal experiments it was found to have primarily anti-edema, antiinflammatory, and coagulation-inhibiting effects. These effects are due to an enhancement of the serum fibrinolytic activity and inhibition of the fibrinogen synthesis, as well as a direct degradation of fibrin and fibrinogen. Bromelain lowers kininogen and bradykinin serum and tissue levels and has an influence on prostaglandin synthesis, thus acting antiinflammatory. In in vitro and in animal studies, experimentally induced tumours could be inhibited by bromelain. Although many studies do not give extensive statistical data, the effects of bromelain in animal studies seem to be dose-dependent. Further investigations have to be carried out.

Bioavailability of 125I bromelain after oral administration to rats.

Bromelain is a sulphydral protease, derived from the stem and fruit of pineapples. Semi-purified preparations of bromelain are used in the treatment of inflammation and oedema. There is however no unequivocal proof of the absorption of the enzyme after oral administration. In this study, 125I-bromelain was administered orally to rats and blood sampled at various times. The total radioactivity, the TCA precipitable 125I-compounds and the molecular weight profile of 125I-proteins in the plasma were determined. A maximum level, equivalent to 270 ng ml-1 bromelain was found at 1 h after administration. Approximately 40 per cent of the 125I in plasma could be precipitated by 10 per cent trichloroacetic acid. Electrophoretic analysis showed one major peak of radioactivity in the plasma samples, with a molecular weight of 26-32,000 daltons. This is identical to the main molecular weight fraction in the Bromelain mixture and corresponds to the molecular weight of the purified enzyme. In the 1 h plasma sample this peak contained 0.003 per cent of the administered dose per millilitre.