Proteolytic enzymes: a new treatment strategy for prosthetic infections?

by Selan L, Berlutti F, Passariello C, Comodi-Ballanti MR, Thaller MC

Istituto di Microbiologia, Facolta di Farmacia, Universita La Sapienza, Rome, Italy.
Antimicrob Agents Chemother 1993 Dec;37(12):2618-21

Among the different mechanisms of bacterial resistance to antimicrobial agents that have been studied, biofilm formation is one of the most widespread.  This mechanism is frequently the cause of failure in the treatment of prosthetic device infections, and several attempts have been made to develop molecules and protocols that are able to inhibit biofilm-embedded bacteria.  We present data suggesting the possibility that proteolytic enzymes could significantly enhance the activities of antibiotics against biofilms.  Antibiotic susceptibility tests on both planktonic and sessile cultures, studies on the dynamics of colonization of 10 biofilm-forming isolates, and then bioluminescence and scanning electron microscopy under seven different experimental conditions showed that serrapetase greatly enhances the activity of ofloxacin on sessile cultures and can inhibit biofilm formation.

A new method for evaluating mucolytic expectorant activity and its application. II. Application to two proteolytic enzymes, serratiopeptidase and seaprose.

Kase Y, Seo H, Oyama Y, Sakata M, Tomoda K, Takahama K, Hitoshi T, Okano Y, Miyata T. Arzneimittelforschung. 1982;32(4):374-8. PMID: 7049188 [PubMed - indexed for MEDLINE]
Using our new method described in a preceding paper, in vivo effects of two proteolytic enzymes such as serratiopeptidase (SER) and seaprose (SAP) on sputa collected from bronchitis rabbits were examined. SER (20 mg/kg) and SAP (30 mg/kg) significantly reduced the viscosity of sputum (P less than 0.05) at the 1-3-h periods and the 4-6-h periods, respectively, after intraduodenal administration. 50 mg/kg of SER also significantly decreased not only viscosity (P less than 0.001) but also amount of freeze-dried substance (P less than 0.05) of sputum at the 1-3-h periods, but SAP did not affect the amount of dried substance. Both enzymes significantly increased the volume of sputum, probably as the result of liquefaction. Thus, mucolytic expectorant activity of both enzymes can be demonstrated first by the reduction in viscosity and next of the increase in volume of sputa. However, the decrease in amount of freeze-dried substance is not always in accord with the reduction viscosity.