Pharmacology of Spiramycin

Diversity and bioactive potential of Actinomycetia from the rhizosphere soil of Juniperus excelsa

Microbial natural products are among the main sources of compounds used in the medical biotechnology field for the purpose of drug development. However, as antibiotic resistance in pathogenic microorganisms is known to be increasing dramatically, there exists a need to develop new antibiotics. Actinomycetia have proven to be a good source of biologically active compounds, although the rediscovery of previously known compounds significantly slows down the introduction of new antibiotics. As a consequence, increasing attention is being paid to the isolation of actinomycete strains from previously unexplored sources, which can significantly increase the likelihood of discovering new biologically active compounds. This study investigated the diversity and bioactive potential of 372 actinomycete strains isolated from the rhizosphere soil of Juniperus excelsa M. Bieb. The examined actinomycete strains belonged to 11 genera, namely, Actinoplanes, Actinorectispora, Amycolatopsis, Kribbella, Micrococcus, Micromonospora, Nocardia, Promicromonospora, Rhodococcus, Saccharopolyspora and Streptomyces. The bioactive potential of each isolated actinomycete strain was determined on the basis of its ability to produce antimicrobial metabolites against Gram-positive and Gram-negative bacteria and yeast. Some 159 strains (42.74%) exhibited antimicrobial activity against at least one of the tested microbial strains. The dereplication analysis of the extract of the Streptomyces sp. Je 1-651 strain, which exhibited strong antimicrobial activity, led to the annotation of spiramycins and stambomycins. Moreover, the phylogenetic analysis based on the 16S rRNA gene sequence of the Je 1-651 strain revealed it to be close to the S. ambofaciens.

Spiramycin in triple therapy of Helicobacter pylori-associated peptic ulcer disease. An open pilot study with 12-month follow-up

BACKGROUND

Spiramycin (Rovamycin) is a well-established macrolide antibiotic with good anti-Helicobacter pylori activity in vitro. It is acid-stable and found in high concentration in various body fluids and cells after oral administration. Its anti-H. pylori activity in vivo has not yet been tested.

METHODS

Twenty-five consecutive patients with endoscopically verified peptic ulcer and a positive biopsy urease test were given spiramycin tables 1.5 MIU instead of oxytetracycline 500 mg q.d.s. in our triple therapy regimen with bismuth subnitrate suspension 10 mL (150 mg bismuth subnitrate) q.d.s. and metronidazole 400 mg t.d.s. for 10 days. Bismuth was taken between meals and spiramycin and metronidazole with meals. Re-endoscopy and 14C-urea breath test were performed 4 weeks after completion of therapy. Those who were H. pylori negative according to the breath test returned for 1-year follow-up.

RESULTS

Per protocol analysis at 4 weeks showed that 21 out of 23 patients were H. pylori negative and had healed ulcers. These 21 patients were persistingly H. pylori negative and had no ulcers at 1-year follow-up. H. pylori eradication and ulcer healing rates were thus 91.3%; 95% confidence interval from 72.0% to 98.9%. Side-effects limiting daily activity were significantly less frequent than we have experienced previously using oxytetracycline in triple therapy.

CONCLUSIONS

Spiramycin appears to be an alternative to tetracycline in the triple therapy of H. pylori infection. Further studies to position spiramycin as an anti-H. pylori drug are warranted.