Germanium (Ge) - Scientific Paper Abstracts

Biol Trace Elem Res 1994 Aug;42(2):151-164

Effects of germanium and silicon on bone mineralization.

Seaborn CD, Nielsen FH

United States Department of Agriculture, Grand Forks Human Nutrition

Research Center, ND 58202.

The chemical properties of Ge are similar to Si. This study investigated whether Ge can substitute for, or is antagonistic to, Si in bone formation. Sixty male weanling Sprague-Dawley rats were randomly assigned to treatment groups of 12 and 6 in a 2 x 4 factorially arranged experiment. The independent variables were, per gram fresh diet, Si (as sodium metasilicate) at 0 or 25 micrograms and Ge (as sodium germanate) at 0, 5, 30, or 60 micrograms. Results confirmed that Ge does not enhance Si deprivation and provided evidence that Ge apparently can replace Si in functions that influence bone composition. When Si was lacking in the diet, calcium and magnesium concentrations of the femur were decreased; this was reversed by feeding either Ge and/or Si. Similar effects were found for zinc, sodium, iron, manganese, and potassium of vertebra. There were some responses to Si deprivation that Ge could not reverse; Ge did not increase femur copper, sodium, or phosphorus or decrease molybdenum of vertebra, effects that were evoked by Si supplementation. Additionally, some findings suggested that 60 micrograms Ge/g diet could be a toxic intake for the rat. On the other hand, some responses induced by Ge indicate that this element may be acting physiologically other than as a substitute for Si. Germanium itself affected bone composition. Germanium supplementation decreased Si and molybdenum in the femur and increased DNA in tibia. Regardless of the amount of Si fed, animals fed 30 micrograms Ge/g diet had increased tibial DNA compared to animals fed 0 or 60 micrograms Ge; however, tibial DNA of animals fed 30 micrograms Ge was not statistically different from those animals fed 5 micrograms Ge. Thus, Ge may be of nutritional importance.

Gen Pharmacol 1993 Nov;24(6):1527-1532

Effect of organic germanium compound (Ge-132) on experimental osteoporosis in rats.
Fujii A, Kuboyama N, Yamane J, Nakao S, Furukawa Y

Department of Pharmacology, Nihon University School of Dentistry, Chiba,

Japan.

1. The therapeutic effect of organic germanium compound, 2-carboxyethyl germanium sesquioxide (Ge-132), for experimental osteoporosis was studied using ovariectomized rats maintained on a low calcium containing diet. 2. Serum calcitonin (sCT) level was decreased and serum parathyroid hormone (sPTH) level was increased by ovariectomy and the decrement and increment rates, respectively, were reduced by administration of Ge-132. Thus, the sCT/sPTH ratio was greater in the groups given Ge-132, indicating that the resorption was somehow inhibited by Ge-132. 3. The transverse strength of femur bone was significantly enhanced by Ge-132. 4. A trend was found in the group given Ge-132 for a larger femur cortical bone index. 5. The relative femur bone wet weight was greater in the group given Ge-132. 6. These results indicate that Ge-132 prevents decreased bone strength, and affects the femur cortical bone index, and bone mineral mass caused by osteoporosis.

Inhibitory effect of Germanium (IV) sodium ascorbate on the in vitro reverse transcriptase of Human immunodeficiency virus
A.M. Badawi, in Metal Ions in Biology and Medicine. Eds. Ph. Collery, LA. Poirier, M. Manfait, J.C. Etienne. John Libbey Eurotext, Paris 0 1990, pp. 517-519

Department of Application, Petroleum Research Institute, Nasr City, Cairo, Egypt

Abstract

Many factors involved in host resistance to acquired immune deficiency syndrome (AIDS) might be significantly dependent upon the availability of ascorbate. Ascorbic acid was investigated for its inactivation of bacterial viruses (Murata, 1974; Murata et al., 1975). The mechanism of in vitro viral inactivation is still unclear. It was postulated that free-radical intermediates produced during ascorbate oxidation are the active agents in viral inactivation (Murata, 1975).

Carboxyethyl germanium sesquioxide (Ge-132) was recently disclosed as an oral interferon inducer with antiviral activity (Ishida et al., 1984).

To investigate the possibility that the antiviral activity of ascorbic acid can be potentiated with germanium, it occurred to us to react ascorbic acid with sodium germanate to give the corresponding germanium and sodium ascorbate derivative (GeNaA).

The resulting compound was submitted to U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, U.S.A., for reverse transcriptase (RT) assay for human immunodeficiency virus (HIV). GeNaA was found to significantly inhibit in vitro RT suggesting AIDS-retarding activity.

Discussion

The HlV-RT result summery shows that GeNaA inhibited HlV-RT by 50% at approximately 99 mcg/ml, 50 mcg/ml and 20 mcg/ml during three different experiments. The first LD50 value 99 mcg/ml appears to be too high and may be dropped, thus the LD50 will be average of the other two values: 50 and 20 mcg/ml. The investigation presented here demonstrates that GeNaA has a significant inhibitory effect on HIV replication in vitro and might be related to an unclear mechanism of action targeted at RT. Although organic germanium's properties of oxygen modulation are not yet precisely elucidated (Goodman, 1988), the possible oxygenating effect of germanium and/or dehydroascorbic radical might be responsible for the inhibition of HIV RT enzyme.