What Are the Benefits of Astragalus Root in Hindi?

Astragalus is the dried root of the Mongolian milkvetch (Astragalus membranaceus (Fisch.) Bge. var. mongholicus (Bge.) Hsiao) or the membranous milkvetch (A. membranaceus (Fisch.) Bge.), of the legume family. It is sweet and warm in nature, entering the spleen and lung channels. It tonifies Qi and strengthens the the spleen, raising yang to lift the depressed, benefiting the defense to strengthen the body's resistance, diuresis to reduce swelling, and supporting the growth of new tissue by detoxification. It is widely used in traditional Chinese medicine to treat internal injuries and fatigue, spleen deficiency diarrhea, lung deficiency cough, organ prolapse, vomiting blood, bloody stools, menorrhagia, edema, or long-term ulceration that does not heal, and all symptoms of qi and blood deficiency.

The main chemical components of astragalus roots are astragalus polysaccharide (APS), saponins, flavonoids and amino acids [2]. The polysaccharide components of astragalus mainly include glucan and heteropolysaccharides. Glucan includes water-soluble and water-insoluble glucans, which are α-(1→ 4)(1→6) glucan and α-(1→4) glucan, respectively. Heteropolysaccharides are mostly water-soluble acidic heteropolysaccharides, which are mainly composed of glucose, rhamnose, arabinose and galactose. A small amount contains uronic acid, which is composed of galacturonic acid and glucuronic acid; some heteropolysaccharides are composed of only glucose and arabinose [3]. This review focuses on the pharmacological effects of APS in the prevention of atherosclerosis, protection of the retina, improvement of memory and cognitive function, anti-aging, prevention of osteoporosis and treatment of Parkinson's disease.

1 Anti-atherosclerosis

Atherosclerosis has a very high incidence and seriously endangers human health. The causes of the disease are complex, and APS can prevent atherosclerosis mainly by intervening in its risk factors, such as regulating abnormal blood lipids [4], anti-hypertensive damage [5], anti-diabetes and improving insulin resistance [6], anti-oxidative stress, anti-infection and inflammatory response, and inhibiting homocysteine levels. In addition, APS can intervene in cells related to atherosclerosis pathogenesis, such as anti-platelet aggregation and activation, regulating macrophage foam cell formation, anti-endothelial cell damage, inhibiting smooth muscle cell proliferation, and regulating dendritic cell inflammatory immune activation [7].

Zhang Jingfang et al. [8] used a high-fat diet to induce an atherosclerosis model and observed the effect of astragalus polysaccharide on the atherosclerosis model. They found that compared with the model group, the total cholesterol, triglycerides, endothelin 1, and malondialdehyde were significantly reduced, while nitric oxide, superoxide dismutase and total antioxidant activity were significantly increased. The area of aortic intima plaques was significantly reduced. It was concluded that astragalus polysaccharide has an anti-atherosclerotic effect, and its mechanism may be related to its antioxidant and protective effects on vascular endothelial cells.

Phagocytosis of lipids by macrophages to form foam cells is the key to the formation of atherosclerotic plaques. Toll-like receptor 4 (TLR4) on the macrophage membrane is related to the formation of atherosclerotic plaques [9]. Chen Rui et al. [10] observed the intervention of astragalus polysaccharide on “mildly oxidized modified low-density lipoprotein (mmLDL)-TLR4-macrophages” and found that APS can inhibit the increase in the phosphorylation levels of TLR4, Syk, Erk, and Paxillin protein phosphorylation levels induced by mmLDL, thereby reducing lipid accumulation in cells, reducing the production of foam cells, and thus exerting an anti-atherosclerotic effect; and the above effect of APS is enhanced within a certain range with increasing concentration. This reveals that APS has the effect of anti-atherosclerosis and stabilizing vulnerable plaques, providing clues for future clinical and experimental research.

2 Retinal protection

Retinopathy is a common eye disease, and in recent years, there has been a lot of research on the protective effect of astragalus polysaccharide on retinal cell damage. The retina is histologically divided into 10 layers, from the outside in: the pigment epithelium layer, cone and rod cell layer, external limiting membrane, external granular layer, external plexiform layer, internal granular layer, internal plexiform layer, ganglion cell layer, nerve fiber layer, and internal limiting membrane. Si Junkang et al. [11] observed that astragalus polysaccharide has a protective effect on hydrogen peroxide-induced oxidative damage to retinal ganglion cells (RGCs) in rats. Among them, the cell activity of the astragalus polysaccharide intervention group at each concentration was higher than that of the hydrogen peroxide damage group by the MTT method, indicating that astragalus polysaccharide can inhibit hydrogen peroxide-induced apoptosis of rat RGCs. In recent years, it has been found that oxidative damage to retinal pigment epithelium (RPE) cells is related to the occurrence of age-related macular degeneration [12-14].

ARPE-19 cells are derived from the RPE of adult retinas and can reflect various functions of RPE. They have been widely used as an in vitro cell model to explore the function and molecular mechanism of human RPE. The use of hydrogen peroxide to damage ARPE-19 cells to simulate the oxidative stress state of the RPE in vivo has been confirmed many times [15-18]. Si Junkang et al. [19] induced oxidative damage in ARPE-19 cells cultured in vitro with hydrogen peroxide, and intervened and protected with different concentrations of APS, confirming the protective effect of APS on hydrogen peroxide-induced oxidative damage to ARPE-19 cells. This study provides a certain experimental basis for the treatment of diabetic retinopathy with Astragalus drugs.

3 Improve memory and cognitive function

Alzheimer's disease (AD) is a common degenerative disease of the central nervous system. The main pathological changes are a decrease in the number of neurons in the hippocampal tissue and the formation of senile plaques (SPs) on the face. The main component of SPs is β-amyloid (Aβ) [20]. The pathogenesis of AD has not yet been fully understood, and there are only various hypotheses, including the cholinergic neuron hypothesis, the β-amyloid toxicity hypothesis, the Tau protein hypothesis, the insulin hypothesis, and the free radical damage hypothesis. At present, the main treatment for Alzheimer's disease is to slow down its progression [21].

 In early AD mice, the main manifestation is a decline in learning and memory abilities. Studies have found that APS can improve the learning and memory abilities of mice [22]. Fei Hongxin et al. [23] used an AD mouse model induced by bilateral intraventricular injection of Aβ1-42 to explore the factors related to learning and memory in mice using a water maze to test their learning and memory abilities. The results showed that APS played a role in the treatment of AD by inhibiting the levels of Aβ and IL-6 proteins, thereby improving the learning and memory functions and hippocampal neuronal morphological structure of AD model mice, reducing their damage, and even restoring them to varying degrees. It also reduced the degree of blood-brain barrier damage in AD model mice. All of this suggests that APS has a certain therapeutic effect on AD mice, providing a theoretical basis for clinical research and development and treatment.

Type 2 diabetes (T2DM) can lead to brain damage, which is mainly manifested as memory loss and cognitive impairment. Li Na et al. [24] studied the effects of APS on type 2 diabetic model rats and found that the superoxide dismutase activity in the hippocampus of rats in the medium and high dose groups of APS was significantly enhanced, and the malondialdehyde content in the hippocampus was significantly reduced, confirming that astragalus polysaccharide has the effect of improving cognitive impairment caused by DM, and may protect against brain damage caused by T2DM through antioxidant stress and anti-apoptotic effects. In clinical practice, it has been found that astragalus has a certain effect on patients with memory loss caused by DM, which proves its effect on improving DM brain damage. The mechanism may be to protect nerve cells by anti-oxidation, anti-infection and anti-apoptosis.

4 Anti-aging

Studies have shown that the essence of aging is the decline of stem cells, a decrease in immunity, the degeneration of the functions of tissues and organs, and the decline of anti-aging genes. Cellular aging is caused by free radicals, which have strong oxidative reactivity. Excessive oxygen free radicals can lead to damage to neuronal cells, reducing the total RNA and protein content in the brain, and decreasing the density of neurons in the brain, resulting in a decline in learning and memory abilities and aging in animals [25].

Astragalus has the effect of enhancing the body's resistance to free radical damage and anti-aging. The saponins, flavonoids and polysaccharides contained in the traditional Chinese medicine astragalus extract have the effect of scavenging superoxide anions and hydrogen free radicals, increasing the activity of superoxide dismutase, catalase and catalase in animals and reduce lipid peroxidation levels in animals [26]. D-Galactose is a normal nutrient component of the body. When there is too much of it, galactose oxidase can catalyze its conversion into aldose and hydrogen peroxide, which produces superoxide anion radicals. Zhong Ling et al. [27] reproduced a D-galactose mouse aging model and found that astragalus polysaccharides can increase the thymus index and spleen index of aging model mice; reduce malondialdehyde content and increase the activity of and increase the activity of superoxide dismutase, glutathione peroxidase and catalase. The anti-aging effect of APS and its mechanism may be achieved by enhancing the body's immune function, improving the body's antioxidant capacity and directly scavenging free radicals.

5 Anti-osteoporosis

Estrogen deficiency can lead to bone loss. Zhang Hongbo et al. [28] established a model of osteoporosis in ovariectomized rats by removing the ovaries of 8-month-old female SD rats to explore the effect of astragalus polysaccharide on osteoporosis in rats. It was found that astragalus polysaccharide has a preventive effect on osteoporosis in ovariectomized rats, and it is considered to have both an inhibitory effect on bone resorption and a promoting effect on bone formation in ovariectomized rats. It has been reported [29] that APS plays a bidirectional regulatory role in the proliferation and differentiation of osteoblasts in vitro, and also has a certain restorative effect on the proliferation ability of naturally aging osteoblasts. APS can inhibit the number and activity of osteoclasts, prevent bone mass loss in ovariectomized mice, and is different from nierestrol, which mainly inhibits bone resorption [30], and has no stimulating effect on the animal's uterus. In recent years, long-term use of hormone replacement therapy by menopausal women has certain side effects. Astragalus polysaccharide is an extract of astragalus, a key tonic medicine that benefits the qi without significant toxic side effects. It can be further developed and used to prevent osteoporosis in postmenopausal women.

6 Prevention and treatment of Parkinson's disease

Chen Lu et al. [31] established a PD rat model and used behavioral and ELISA tests to observe the rat's rotational behavior after 1, 7, and 14 days of treatment in the Astragalus polysaccharide group (APS group) and the pathological changes in the substantia nigra and the changes in the content of inflammatory cytokines in the brain tissue on the 14th day, and compared them with the control group (PD group). It was found that the number of rotations in the APS group was lower than in the PD group, comparable to the positive control group, and the tyrosinase activity was significantly higher than in the PD group. The expression of bFGF protein in the substantia nigra was also lower than in the PD group, and the content of inflammatory cytokines in the brain tissue was also significantly reduced. This indicates that astragalus polysaccharides may treat Parkinson's disease through immunomodulatory effects.

7 Conclusion

Astragalus has extremely high clinical value and is suitable for medicinal food supplements. However, the current clinical use of astragalus is mainly limited to the traditional processing and decoction methods, and the utilization rate and market transformation rate are not high. With the development of modern experimental technology, there is a gradual focus on targeted treatment for specific diseases. Therefore, it is of great significance to study the pharmacological effects of astragalus polysaccharides. At present, extensive research has been conducted on the pharmacological effects of astragalus polysaccharides. Previous studies focused on improving the immune system, anti-tumor, anti-viral, protecting the liver and kidney, lowering blood sugar, and blood pressure. In recent years, research on astragalus polysaccharides has gradually become more detailed, but many mechanisms are still unclear.

This article mainly summarizes the pharmacological effects of astragalus polysaccharides in the prevention of atherosclerosis, protection of the retina, improvement of memory and cognitive function, anti-aging, anti-osteoporosis, and prevention and treatment of Parkinson's disease, in the hope of providing new ways for future research on the prevention and treatment of atherosclerosis, Alzheimer's disease, osteoporosis, and Parkinson's disease. However, clinical research on astragalus polysaccharides is not in-depth, its adverse reactions have not been fully reported, the conversion rate of experimental research results is not high, and it has not been able to serve clinical practice well. Therefore, comprehensive research on astragalus polysaccharides is still a long-term project, and further research is needed in the future to further explore the pharmacological effects of astragalus polysaccharides.

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