STS-107 (short for Space Transportation System #107) is the first space flight to feature an Israeli astronaut, Ilan Ramon, and will be entirely dedicated to science. The Shuttle Columbia and its seven crew-members will devote this 16-day mission to more than 80 different experiments in the space, life, and physical sciences.

IAMI’s experiments will be part of the CIBX-2 payload, which is hosted by ITA Inc. (Commercial Instrumentation Technology Associates Biomedical Experiments).

Among IAMI’s experiments are the following:

M-107® probiotic powdered milk formula for NASA space flight
IAMI and Materna Ltd.

Astronauts during space missions suffer from several harmful physiological derangements, including:

• A decline in the immune function – exposing the astronauts to risks of infections.
• A disruption of calcium metabolism – with rapid bone loss (similar to osteoporosis), with increased risk for bone fractures and kidney stones.
• Changes in the intestinal microflora – with a decrease in the friendly and beneficial bacteria and a rise in the harmful bacteria. This exposes the astronauts to intestinal infections and excessive production of gases, which is a major problem in a space station where astronauts live for months with minimal options for exchanging the closed air environment.

NASA places a great deal of importance in finding “counter-measures” to minimize these negative space-flight effects and maintain the health of the astronauts. Rising evidence supports a beneficial role for probiotics in minimizing these unwanted side effects and we believe that consumption of a probiotic-enriched powdered milk formula by the astronauts before or during space flight would positively influence and enhance immunity, calcium metabolism, and bowel microflora and function, among other beneficial effects. Therefore, with the collaboration of Materna Laboratories LTD, Israel, we are planning to examine M-107®, a Bifidobacterium lactis Bb12-enriched probiotic powdered milk, that has been adapted for consumption by astronauts, who as to date consume powdered milk and not raw fluid milk due to technical storage problems.

During STS-107 we will examine various biologic aspects of Bifidobacterium lactis before, during and after space flight, with ground-based controls. We assume the in vitro activity of the probiotic bacteria will not be significantly altered by space flight, and that this and future studies will establish these beneficial bacteria as suitable for consumption and highly beneficial for astronauts, both before and during space missions. We hope to show that probiotics could constitute an enormous advantage for maintaining the well being of astronauts during future shuttle flights, long duration missions and space station habitation.

Osteoblast MMP-1 gene expression in microgravity on STS-107 space flight
IAMI and The Hadassah-Hebrew University Medical Center, Jerusalem.

As previously mentioned, a decreased osteoblast function is thought to play a role in the process of space flight-induced bone loss. IAMI has previously studied (aboard STS-80 and STS-95) osteoblastic cell morphology in microgravity and found that osteoblasts exposed to microgravity experience many changes when compared with cells grown on Earth. The osteoblasts exposed to microgravity grow slowly, become rounded in shape, with reduced numbers of stress fibers and lower metabolism. These findings indicate that space flight-induced bone resorption may be partially attributed to changes in the osteoblasts proliferation, function, and morphology. Alterations in the gene expression for growth factors and matrix proteins have also been observed in osteoblastic cells in vitro under microgravity conditions. For example, microgravity affects bone cells by reducing type I collagen and osteocalcin gene expression.

Currently, we are planning the next phase of our research. This continuous study will evaluate the role of MMP-1 enzyme in osteoblast cells in microgravity. MMP-1 (also known as collagenase-1 or interstitial collagenase-1) is a matrix metalloproteinase (MMP), a zinc-dependent proteinase capable of degrading all components of connective tissue at physiological pH. It is involved in bone matrix degradation and remodeling. An upregulation of MMP-1 activity has been observed in osteocytes under disuse conditions. Researchers at The Hadassah-Hebrew University Medical Center, Jerusalem, have described a significant increase in both the mRNA levels of MMP-1 and its activity in osteocytes under hypergravititational force.

The purpose of this STS-107 space study is to define the mechanisms and clarify the role of MMP-1 in the weightlessness-induced bone loss during spaceflight.

Defining MMP-1’s expression will enable us to gain a better understanding of osteoblast growth and function in microgravity. The results obtained in this space study will serve as the basis for future elucidation of the microgravity signal transduction pathways and in the long run will facilitate the development of means to re-normalize cell function in microgravity. In addition, the insights gained from this study will allow for advances in understanding and treatment of the diverse disease processes on Earth where MMP-1 is involved, such as the osteoporosis of aging, disuse osteoporosis, tumor invasion and metastasis, cartilage destruction in arthritis, and undesirable tooth-root resorption in orthodontics.