gms | German Medical Science

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2019)

22. - 25.10.2019, Berlin

Raloxifen is more effective than ostarine for muscle tissue in estrogen deficient rats

Meeting Abstract

  • presenting/speaker Louis Noisser - Universitätsmedizin Göttingen, Unfallchirurgie, Orthopädie und Plastische Chirurgie, Göttingen, Germany
  • Stephan Sehmisch - Universitätsmedizin Göttingen, Unfall-, Plastische- und Wiederherstellungschirurgie, Abteilung Unfallchirurgie, Göttingen, Germany
  • Kai O. Böker - Klinik für Unfallchirurgie, Orthopädie und Plastische Chirurgie, Göttingen, Germany
  • Daniel B. Hoffmann - Universitätsmedizin Göttingen, Klinik für Unfallchirurgie, Orthopädie und Plastische Chir., Göttingen, Germany
  • Arndt F. Schilling - Universitätsmedizin Göttingen, Klinik für Unfallchirurgie, Orthopädie und plast. Chirurgie, Göttingen, Germany
  • Wolfgang Lehmann - Universitätsmedizin Göttingen, Unfallchirurgie, Orthopädie und Plastische Chirurgie, Göttingen, Germany
  • Marina Komrakova - Universitätsmedizin Göttingen, Unfallchirurgie, Plastische- und Wiederherstellungschirurgie, Göttingen, Germany

Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2019). Berlin, 22.-25.10.2019. Düsseldorf: German Medical Science GMS Publishing House; 2019. DocAB41-450

doi: 10.3205/19dkou329, urn:nbn:de:0183-19dkou3295

Veröffentlicht: 22. Oktober 2019

© 2019 Noisser et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Fragestellung: Low sex hormone levels are among the key reasons for sarcopenia and muscle weakness. Hormone replacement therapy (HRT) with estrogen or testosterone has been shown to increase muscle mass and function. HRT however can lead to severe side effects. Selective estrogen and androgen receptor modulators (SERMs and SARMs) target similar hormone receptors and are thought to have fewer side effects than HRT.

The present study is focused on the effects of the SARM ostarine (OST) and/or the SERM raloxifene (RAL) on skeletal muscle in estrogen deficient ovariectomized rat model.

Methodik: Three-month-old female Sprague-Dawley rats (n=60) were ovariectomized (OVX), whereas 15 rats were left intact (NON-OVX). OVX rats were divided into 4 groups, each of 15 rats. Group 1 was left untreated (OVX). Group 2 received OST. Group 3 was treated with RAL and Group 4 underwent combined treatment with both OST and RAL (OST+RAL). The average daily doses were 0.6 mg/kg body weight (BW) for OST and 11 mg/kg BW for RAL. OST and RAL were supplied with food. After 13 weeks, BW and uterus weight were recorded. M. gastrocnemius (MG), M. soleus (MS) and M. longissimus (ML) were analyzed. The cross-sectional areas of glycolytic, intermediate, and oxidative fibers in muscles were measured, and the cell-nucleus and capillary density was recorded. In serum creatine kinase activity was assessed.

Ergebnisse und Schlussfolgerung: BW did not differ between groups at the beginning of the experiment. At the end it increased significantly in the OST and OVX groups compared to all other groups. BW of OST rats was higher than BW of OVX rats. The changes in muscle weight were similar to those in BW. Muscle weight was the highest in OST group. Compared to the OVX and OVX+RL groups, the NON-OVX, OST, and OST+RAL groups had a higher uterus weight.

In all muscles studied, the size of fibers was larger in OVX and OST groups than in any other group. The fiber size in RAL and OST+RAL groups was similar to that in the NON-OVX group.

Nucleus density was higher in the OST+RAL group than in the NON-OVX group in the MG. In other muscles, no differences were observed between the groups. In OST group capillary density increased in MS and ML. In MG, the NON-OVX group had the lowest capillary density.

The OST treatment alone increased BW, muscle weight and capillarization, whereas fiber size remained at the level of OVX rats. Enhanced uterus weight after OST treatment alone and in combination with RAL suggests high androgenic activity of OST in the uterus. This may be considered as an unfavorable side effect. Rats under RAL and OST+RAL treatments demonstrated muscle structures similar to NON-OVX rats. RAL treatment alone did not change uterus weight. Thus, RAL treatment appears to be more favorable than OST or OST+RAL for treating muscle tissue in estrogen-deficient individuals. Considering its current application in osteoporosis therapy, RAL could be an alternative treatment for other musculoskeletal diseases.