Puerarin accelerates neural regeneration after sciatic nerve injury

Pharmacological mechanisms of puerarin in the treatment of Parkinson's disease: An overview

Puerarin, a monomer of traditional Chinese medicine, is a key component of Pueraria radix. Both clinical and experimental researches demonstrated that puerarin has therapeutic effects on Parkinson's disease (PD). Puerarin's pharmacological mechanisms include: 1) Anti-apoptosis. Puerarin inhibits cell apoptosis through the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/protein kinase B (Akt) and c-Jun N-terminal kinase (JNK) signaling pathways. Puerarin also exerts a hormone-like effect against cell apoptosis; 2) Anti-oxidative stress injury. Puerarin inhibits the Nrf2 nuclear exclusion through the GSK-3β/Fyn pathway to promote the Nrf2 accumulation in the nucleus, and then promotes the antioxidant synthesis through the Nrf2/ARE signaling pathway to protect against oxidative stress; 3) Neuroprotective effects by intervening in the ubiquitin-proteasome system (UPS) and autophagy-lysosomal pathway (ALP). Puerarin significantly enhances the activity of chaperone-mediated autophagy (CMA), which downregulates the expression of α-synuclein, reduces its accumulation, and thus improves the function of damaged neurons. Additionally, puerarin increases proteasome activity and decreases ubiquitin-binding proteins, thereby preventing toxic accumulation of intracellular proteins; 4) Alleviating inflammatory response. Puerarin inhibits the conversion of microglia to the M1 phenotype while inducing the transition of microglia to the M2 phenotype. Furthermore, puerarin promotes the secretion of anti-inflammatory factor and inhibits the expression of pro-inflammatory factors; 5) Increasing the levels of dopamine and its metabolites. Puerarin could increase the levels of dopamine, homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) in the striatum; 6) Promoting neurotrophic factor expression and neuronal repair. Puerarin increases the expression of glial cell-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), thereby exerting a neuroprotective effect. Moreover, the regulation of the gut microbiota by puerarin may be a potential mechanism for the treatment of PD. The current review discusses the molecular mechanisms of puerarin, which may provide insight into the active components of traditional Chinese medicine in the treatment of PD.

Network pharmacology-based analysis of the effects of puerarin on sarcopenia

Background

With the acceleration of population aging, sarcopenia will place a heavy burden on families and society. Thus, effective treatments urgently need to be developed to slow down the development of sarcopenia. This study adopted a network pharmacological approach to explore the possible mechanisms of puerarin in treating sarcopenia.

Methods

The potential therapeutic targets of puerarin were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database, while the targets of sarcopenia were obtained from the GeneCards, DisGeNET, Online Mendelian Inheritance in Man (OMIM), and Therapeutic Target Database (TTD) databases. The protein-protein interaction (PPI) network was generated by BisoGenet, and core targets were identified by a topological analysis. To determine the potential targeting pathways, the core targets were further imported into the Metascape platform for the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The results were visualized using an online bioinformatics tool.

Results

We identified 53 targets for puerarin and 129 targets for sarcopenia. A total of 206 core targets, which were considered potential therapeutic targets, were identified from the merged PPI network. Further, the GO and KEGG analyses revealed that the functions of the core targets and related pathways were mainly associated with the cell cycle, apoptosis, protein synthesis, and proteolysis.

Conclusions

Puerarin has the potential to treat sarcopenia through the regulation of the cell cycle, apoptosis, and protein homeostasis. Our study has laid a foundation for further studies on drug development and pharmacological experiments in the treatment of sarcopenia.

Pueraria lobata Targeted Preparation Improves the Clinical Symptoms of Cervical Spondylosis by Regulating the Balance of Gut Microbiota

BACKGROUND

Nanotargeted preparations can enhance the safety and effectiveness of medication by altering the pharmacokinetic behavior of drugs in the human body, and Pueraria lobata is shown to be effective in the treatment of neck and back pain.

PURPOSE

This study prepared a nano-Pueraria targeted preparation, in order to analyze its effect on improving the clinical symptoms of cervical spondylosis by adjusting the balance of intestinal flora.

METHODS

A total of 200 patients with cervical spondylosis admitted to the Affiliated Hospital of Nanjing University of Chinese Medicine were enrolled and divided into an observation group and a control group. The control group was given Tuina therapy, and the observation group was given nano-Pueraria targeted preparation + Tuina therapy. The clinical symptoms and intestinal microflora of the two groups were examined before intervention.

RESULTS

It was found that the markedly effective of treatment efficacy of the observation group (98%) was higher than that of the control group (78%) after 15 days of intervention, and the clinical symptoms were obviously fewer than those of the control group. The distribution of gut microbiota showed that there were significant differences in the composition of gut microbiota between the two groups. Compared with the control group, the abundance of Firmicutes in the observation group was significantly higher, while the abundance of Bacteroidetes and Proteobacteria was significantly lower.

CONCLUSION

The targeted preparation of nano-Pueraria can improve the clinical symptoms of patients with cervical spondylosis by adjusting the balance of gut microbiota.

Puerarin ameliorates skeletal muscle wasting and fiber type transformation in STZ-induced type 1 diabetic rats

Puerarin is an isoflavonoid extracted from Pueraria lobate with extensive pharmacological effects in traditional Chinese medicine. The evidence implicates that puerarin mitigates hyperglycemia and various relevant complications. Here, the effect of puerarin on skeletal muscle wasting induced by type 1 diabetes (T1D) was explored. Streptozotocin (STZ)-induced T1D male Sprague Dawley (SD) rats were used in this study. Muscle strength, weight and size were measured. L6 rat skeletal muscle cells were applied for in vitro study. Our results showed that eight-week oral puerarin administration (100 mg/kg) increased muscle strengths and weights accompanied by enhanced skeletal muscle cross-sectional areas in diabetic rats. Simultaneously, puerarin also reduced expressions of several muscle wasting marker genes including F-box only protein 32 (Atrogin-1) and muscle-specific RING-finger 1 (Murf-1) in diabetic group both in vitro and in vivo. Transformation from type I fibers (slow muscle) to type II fibers (fast muscle) were also observed under puerarin administration in diabetic rats. Puerarin promoted Akt/mTOR while inhibited LC3/p62 signaling pathway in skeletal muscle cells. In conclusion, our study showed that puerarin mitigated skeletal muscle wasting in T1D rats and closely related with Akt/mTOR activation and autophagy inhibition. Whether this effect in murine applies to humans remains to be determined.

The Importance of Natural Antioxidants in the Treatment of Spinal Cord Injury in Animal Models: An Overview

Patients with spinal cord injury (SCI) face devastating health, social, and financial consequences, as well as their families and caregivers. Reducing the levels of reactive oxygen species (ROS) and oxidative stress are essential strategies for SCI treatment. Some compounds from traditional medicine could be useful to decrease ROS generated after SCI. This review is aimed at highlighting the importance of some natural compounds with antioxidant capacity used in traditional medicine to treat traumatic SCI. An electronic search of published articles describing animal models of SCI treated with natural compounds from traditional medicine was conducted using the following terms: Spinal Cord Injuries (MeSH terms) AND Models, Animal (MeSH terms) AND [Reactive Oxygen Species (MeSH terms) AND/OR Oxidative Stress (MeSH term)] AND Medicine, Traditional (MeSH terms). Articles reported from 2010 to 2018 were included. The results were further screened by title and abstract for studies performed in rats, mice, and nonhuman primates. The effects of these natural compounds are discussed, including their antioxidant, anti-inflammatory, and antiapoptotic properties. Moreover, the antioxidant properties of natural compounds were emphasized since oxidative stress has a fundamental role in the generation and progression of several pathologies of the nervous system. The use of these compounds diminishes toxic effects due to their high antioxidant capacity. These compounds have been tested in animal models with promising results; however, no clinical studies have been conducted in humans. Further research of these natural compounds is crucial to a better understanding of their effects in patients with SCI.

Effects of Localized X-Ray Irradiation on Peripheral Nerve Regeneration in Transected Sciatic Nerve in Rats

Low-dose radiation has been used in clinical and experimental models for the prevention of scarring and for fracture healing. There is evidence that low-dose radiation improves the hormesis of various cell types but little is known about its effects on peripheral nerve tissue. In this study, we investigated the beneficial effects of low-dose radiation on the regeneration of transectional peripheral nerve injury in an experimental rat model. Seventy-two male Sprague-Dawley rats received transection injury to the left sciatic nerves, and the nerves were subsequently sutured by epineurium end-to-end anastomosis to restore continuity. Animals were randomly assigned to one of two treatment groups (n = 36/group): 1 Gy X-ray irradiation or control (sham irradiation). Gait analysis, electrophysiological examination and morphological investigations were performed. In addition, Western blot and qRT-PCR were performed to determine the level of vascular endothelial growth factor (VEGF) and growth-associated protein-43 (GAP-43). Content of VEGF and GAP-43 in the regenerated sciatic nerve of the irradiated group was higher than the control group. At 4 to 12 weeks after surgery, the irradiated animals exhibited a significantly improved functional recovery relative to controls. At 12 weeks after surgery, amplitude and conduction velocity of the irradiated group were higher than the control group (P < 0.05). The number of nerve fibers, diameter of axons and morphological structure of the myelin sheath in the irradiated group were superior to those of the control group. These results suggest that low-dose radiation contributed to regeneration and functional recovery after transverse peripheral nerve injury by inducing increased production of VEGF and GAP-43, which promote the axonal regeneration and myelination.