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ScienceDaily (Aug. 18, 2006) — University of Florida researchers found that ordinary human brain cells may share the prized qualities of self-renewal and adaptability normally associated with stem cells. Common human brain cells can generate different cells’ types in cell cultures. In addition, when researchers transplanted these human cells into mice, the cells effectively incorporated in a variety of brain regions. Same sorts of tissue from the mouse brain can give rise to rapidly dividing cells, but this shows it is true with human cells.

The findings document the ability of common human brain cells to morph into different cell types, a previously unknown characteristic, and are the result of the research team’s long-term investigations of adult human stem cells and rodent embryonic stem cells.

University of Minnesota stem cell researchers, together with collaborators at Stanford University, have successfully used adult stem cells to replace the immune system and bone marrow of mice, offering the promise of new therapies for people in the future. With this advance and other recent discoveries, the researchers are winning over previous skeptics.

Scientists in the United States and Sweden worked together found firstly that the human hippocampus retains its ability to generate neurons throughout life, even at the age of 60 or 70. The newborn neurons could restore some function for the injured brain. The discovery was found by analysis for the samples of hippocampus tissue from five cancer patients.

Great many observations have found the growth of the new neurons of adult human brain.

If we find some natural medicine resources that are inexpensive and effective with lesser side effect through only oral or injection to restore the injured human brain, would be a promising direction.

1. The mechanism of Chinese medicine on cells regeneration

Clinical practices have been demonstrating that Chinese medicine is superior to Western medicine in the treatment and prevention of brain disorders. Chinese Medicine can directly permeate through the blood-brain barrier into the brain to take the therapeutic effect in improving the state of hypoxic ischemic and metabolism. It will not only promote development of immature neurons, but also to repair the damaged nerve cells. Enhance the activity of nerve cells and restore the injured brain. Such as, Chinese medicines have very good therapeutic effect on the congenital cerebral palsy, sequela of cerebrovascular disease and traumatic brain injury as well as Alzheimer’s disease, etc.

Chinese medicine contains various natural nutrients that are easily absorbed by our body, such as, amino acids, peptides, phospholipids and so on. So the treatment in Chinese medicine is able to generate magical effect that simply can not get in the treatment of medication or surgery in Western medicine. Chinese medicine is a kind of restorative treatment in the level of cell and gene, through providing nutrients for the damaged nerve cells, to promote residual neurons regeneration. Therefore the damaged function of the nerve system will be restored.

1.1. Promotion of nerve cell’s differentiation and development

In vitro, vivo and clinical trials in the conditions of normal, hypoxic and glutamate damage, shows that Chinese medicine can increase cells’ activity, promote nerve cell’s differentiation and development. Inhibit the apoptosis of nerve cells in the earlier, middle and later stage, which induced by hypoxic and glutamate damage.

1.2. Promotion of neuronal growth

Neonatal rat’s dorsal root ganglia in serum-free culture, for the test group add the Chinese medicine in basic culture medium, control group add nothing. In the test group, the length of dorsal root ganglion cells neurites are (314 ± 43) μm. It is significantly larger than that of (76 ± 26) μm in control group. These results indicate that, in vitro, Chinese medicine can promote the growth of dorsal root ganglia and cerebral cortex neurons.

1.3. Activation of undifferentiated stem cells

In the central nervous system, there are some undifferentiated stem cells. Chinese medicine possesses the ability to activate those stem cells to split and regenerate new cells. So that make the nerve cells be restored to normal levels from original absolutely decreased status.

Ischemic injured Brain, after 7 days’ treatment of Chinese medicine, in ischemic injured area, found a great number of nestin expressions. This showes that Chinese medicine possesses a strong ability to promote the proliferation of adult neural stem cells in vivo. The Experiments also observed that the functional recovery of patients’ limb is sync with the increase of nestin level. The results proved that the Chinese medicine can effectively promote the nestin expression. Therefore contribute to rebuild nerve tissue effectively after cerebral ischemia damage.

2. Protection of Cells

2.1. Protection of neuronal apoptosis and injury

Experimental evidences suggest that cell apoptosis is one of the main reasons for neuronal loss in degenerative diseases, such as, aging, Alzheimer and Parkinson diseases. Recent years, clinical studies have shown that Chinese medicine have a certain effect on senile dementia.

In the condition of ultraviolet induced apoptosis and injury of neuron strain differentiation PC12, that ginsenosides showed good protective effect for PC12 cells. A large number of data indicate that ginsenosides have a certain stabilizing effect on membrane, and can participate in the regulating the level of intracellular calcium. Prompted that ginsenoside may contribute to the regression neural diseases, such as, Alzheimer’s disease and Parkinson disease, etc.

2.2. Inhibition of intracellular calcium overload

Studies have shown that the Rg1 and Rb1 of ginsenosides can significantly increase the survival time of cultivated hippocampal neurons through inhibiting intracellular calcium overload mediated by high concentrations of glutamate to reduce the mortality rate.

2.3. Prevention of damage of free radical on nerve cells

The study found that ginsenosides have protective effect on free radical damage for cultured rat cortical neurons. Compared with control group, the release of LDH is significantly reduced. The cells’ survival rate is significantly higher.

2.4. Protection of ultra structure of nerve cells

Chinese medicine can protect ultra structure of nerve cells and mitigate against the cells’ injury caused by hypoxia and glutamate. The protection takes the effect in two ways, one is indirect effect by glial cell mediating and the other one is direct effect on nerve cells. Its primary target is the glial cells.

In hypoxic mice model, test group was given Chinese medicine and control group no medicine. Ultra-micro pathological observation shows that, in control group, various pathological changes happen in brain tissue. Such as neuron cells edema, mitochondrial swelling, rough endoplasmic reticulum expansion, decrease in the number of ribosomes, fluid accumulation around some of the glial cell nuclear, some cell organelle dissolved, swelling in some of nonmyelinated nervefiber, difference in capillary diameter, swelling in some of endothelial cells, and so on.

However, Chinese medicine group keeps in normal or slight pathological changes in brain tissue. Researchers believe that the mechanism of Chinese medicine reducing brain damage is that reduce the content of lipid peroxidation product-MDA by increasing the activity of SOD, reduce the brain cells’ damage from free radicals. So as to achieve the purpose of protecting brain cells.

3. Inhibition of mitosis and cell proliferation

Experiments confirmed that some Chinese herbs possess strong immunosuppressive activity and could be used as an immunosuppressant in clinical autoimmune disease.

In vitro immune response test, Chinese medicine can inhibit MLR and inhibit the division and proliferation of lymphocyte cell induced by mitogen, such as PHA, ConA, LPS and PWM. When the drug concentration in 3mg/ml, inhibit 85% of the PHA and ConA response, almost entirely inhibit MLR, LPS and PWM response.