[Experimental acceleration of fracture repair by biochemical media (author's transl)]

Therapeutic Effects of Ribunucleinate (Ribonucleotides) in Immuno-Inflammatory and Arthritic Diseases

Ribonucleic acids from different organs and from yeast have been used for the treatment of chronic and degenerative diseases in the context of naturopathic medicine in the last 60 years. This chapter provides general information about ribonucleinates as therapeutic agents. Past and present pharmacological and clinical investigations are discussed in the field of the central nervous system, sensory organs, cancer and degenerative diseases of joints and vertebra.

Effects of Osteochondrin S and select connective tissue ribonucleinate components on human osteoclasts in vitro

Objectives

Osteochondrin S, a natural product derived from connective tissues and yeast, is used to treat osteoarthritis. The aim of this study was to determine the effect of Osteochondrin S on human osteoclast activity in vitro.

Methods

Osteoclasts were derived from human peripheral blood mononuclear cells stimulated with macrophage colony-stimulating factor and receptor activator of nuclear factor kappa B (RANK) ligand. Cells were treated with 23.5–587.2 ng/ml Osteochondrin S or 0.2–5 mg/ml of RNA components (synovia, placenta, intervertebral disc or cartilage). The effects on osteoclast formation and resorptive activity were assessed. Real-time polymerase chain reaction was conducted to assess the expression of key osteoclast genes.

Key findings

Osteochondrin S and the individual RNA extracts resulted in a concentration-dependent inhibition of human osteoclast activity. Osteochondrin S did not affect RANK, nuclear factor of activated T cells (NFATc1), osteoclast-associated receptor or cathepsin K expression. However, there was a significant (P < 0.05) reduction in mRNA expression of calcitonin receptor. Osteochondrin S treatment also significantly increased the expression of osteoclast inhibitory factor interferon-β and, interestingly, increased the expression of tumour necrosis-α-like weak inducer of apoptosis (TWEAK).

Conclusions

Osteochondrin S inhibited the resorptive ability of osteoclasts. These actions are likely to occur at a late stage during osteoclast formation, downstream of NFATc1. Overall, the findings show that Osteochondrin S inhibition of osteoclast activity may be responsible for its beneficial effects on diseases such as osteoarthritis.

Aprotinin application has no negative effect on osseous implant integration: a biomechanical and histomorphometric investigation in a rat model

Intraoperative blood loss requiring allogenic blood transfusion (ABT) is a common problem in major orthopedic surgery. Since transfusion related side effects up to fatal consequences due to blood type incompatibility cannot be excluded completely, it is desirable to reduce the amount of blood loss and transfusions to a minimum. Encouraging results in the application of aprotinin, a natural protease-inhibitor with antifibrinolytic, bleeding-reducing properties, in thoracic-, heart- and abdominal surgery led to the use of aprotinin also in orthopedic surgery. One important safety issue in the use of aprotinin in orthopedic surgery is a possible negative effect on the osseous integration of an implant due to the multiple interactions of aprotinin with several enzymatic systems. In this study, we therefore investigated the influence of aprotinin on the osseous ingrowth of a titanium-implant in a rat model. Forty female Sprague-Dawley rats underwent unilateral retrograde nailing of the femur. Animals were divided in two groups, one receiving i.v. aprotinin intraoperatively, the other group receiving the same amount as saline solution. After 56 days animals were killed and from each group half of the femora were prepared for biomechanical testing, the other half for histological examination. The push-out experiment revealed no significant difference between the aprotinin-group and the control-group, both showing comparable shear stresses. In addition, the histomorphometrical analysis showed comparable implant integration between both groups. The results demonstrate that perioperative aprotinin application has no negative effect on osseous implant integration in a rat model.

Calcitonin and fracture healing. An experimental study on rats

The effects of systemically administered calcitonin (CT) on fracture healing were analyzed in an experimental study on rats. The healing of a fracture was followed from 3 days up to 9 weeks postoperatively. Half of the rats in each age group were given daily CT 10 MRC-U/kg body wt s.c. Mechanical properties of the healing tibial fractures (tension strength) as well as various connective tissue components of the callus tissue were analyzed. No difference in the radiological or microscopical appearance of the fractures was detectable between the animals receiving CT and the controls. In the biochemical analysis matrix production as assessed from the concentrations of nitrogen, hexosamines, and hydroxyproline within the callus followed the usual lines of undistributed fracture union without any difference between the groups with and without CT. No differences could be detected in the mineralization of the callus between the specimens from animals receiving CT and those without. The tensile strength values of the fractures increased almost linearly up to 9 weeks. At 1 week the tensile strength values for fractures union in the animals without CT were approximately 50% higher, but later on no differences could be detected between the groups. These results indicate that although in the early phases of long-term CT therapy collagen synthesis may be impaired, there will be no effect on the net content of collagen or calcifying tissue in the callus or on the mechanical strength of healing fractures.

Calcitonin and granulation tissue formation in the rat. An experimental study

The effects of systemically administered calcitonin (CT) on granulation tissue development were compared using viscose cellulose sponges as wound model in the rat. The ingrowth of new granulation tissue was analyzed for the contents of various connective tissue components (total nitrogen, hydroxyproline, DNA, and RNA) and for the differential counts of the cells infiltrating the sponges. The results indicate that up to 4 weeks postoperatively (p.o.) CT did not affect the net amount of collagen, measured as hydroxyproline, total nitrogen, aminosugars nor the dynamics of differentiation and viability of the invading cells. The present observation that CT has negligible effects, if any, on the early stages of connective tissue formation and on the cell population indicates that surgical procedures could be carried out safely during systemic CT therapy without an increased risk of wound complications.

Effect of kallikrein-kinin system on calcium-vitamin D3 metabolism

Kallikrein has been reported to stimulate callus formation and cell proliferation. It is well-known that vitamin D3 play an role on the metabolism of calcium. However, the relation between vitamin D3 and kallikrein are still poorly understood. We have studied the effect of kallikrein on calcium and vitamin D3 with canine kidney. Mongrel dogs were anesthetized with sodium pentobarbital and prepared by the method of Nakanishi et al. Drugs were infused into renal artery for 60 minutes under three different serum calcium concentrations (Exp. I, Exp. II, Exp. III). Blood samples were collected at the midpoint of the 60 minutes urine collection period. Plasma vitamin D3 concentrations were measured by the metabolites of 25-hydroxyvitamin D3 and 1 alpha,25-dihydroxyvitamin D3. 25-hydroxyvitamin D3 was estimated by competitive protein binding assay and 1 alpha,25-dihydroxyvitamin D3 was determined by radioreceptor assay after separated using HPLC. Electrolytes of sodium, potassium, chloride, calcium and phosphorus in serum and urine, plasma cyclic AMP, glomerular filtration rate, renal blood flow and blood pressure were also measured respectively. Plasma 1 alpha,25-dihydroxyvitamin D3 concentration was found to be decreased by the infusion of kallikrein (0.02 KU/kg/min) in three experimental conditions, especially in Exp. II. Bradykinin (0.02 microgram/kg/min) also caused to kallikrein-like changes of vitamin D3. It is suggested that kallikrein-kinin system is related to inhibit the mechanism of vitamin D3 activation system on kidney.