Research progress on medicinal components and pharmacological activities of polygonatum sibiricum.

ETHNOPHARMACOLOGICAL RELEVANCE: Polygonatum sibiricum, commonly known as Siberian Solomon's seal, is a traditional herb widely used in various traditional medical systems, especially in East Asia. In ancient China, the use of polygonatum sibiricum in medicine and food was mentioned in Li Shizhen's Bencao Gangmu of traditional Chinese medicine (TCM). It was also used in history of India in Vedic medicine. The plant is rich in bioactive substances such as polysaccharides, saponins, flavonoid and alkaloids. AIM OF THE REVIEW: The aim of this review is to understand the pharmacological and pharmacokinetics research progress of the major components of polygonatum sibiricum, and to prospect its potential application and development in the treatment of various diseases. MATERIALS AND METHODS: We conducted a systematic literature search against major online databases on the Web, including PubMed, ancient books, patents, PubMed, Wiley, Google Scholar, Web of Science, and others. We select the pharmacological process and mechanism of the main components of polygonatum sibiricum in a variety of diseases, and make a strict but careful supplement and in-depth elaboration to this review. RESULTS: Several studies have demonstrated the strong antioxidant properties of polygonatum extract, which can be attributed to the presence of flavonoids and other polyphenol compounds; for diabetes and other metabolic-related diseases, polygonatum saponins have particular advantages in regulating intestinal flora and lipoprotein concentration in organisms. In addition, the polysaccharides extracted from this plant have a strong anti-inflammatory effect, which is related to its ability to regulate proinflammatory cytokine and mediators. In the aspect of anti-tumor effect, polygonatum derivatives can induce cancer cell apoptosis mainly by adjusting the cell membrane potential and cell cycle. It is worth noting that the combined action of the main components of polygonatum also offers promising solutions for the treatment of the disease. CONCLUSION: Polygonatum polysaccharide has therapeutic effects on many diseases by adjusting cell signal pathways, polygonatum sibiricum have significant advantages in regulating intestinal flora, inducing apoptosis of tumor cells, activating antioxidant processes, etc. Further research and basic exploration are needed to prove the function and mechanisms of the main components of polygonatum sibiricum on related diseases. The study on the immunomodulatory properties of polygonatum revealed its potentiality of enhancing immune function, which made it an interesting subject for further exploration in the field of immunotherapy.

The Mechanism of Aerobic Exercise Regulating the PI3K/Akt-mTOR Signaling Pathway Intervenes in Hippocampal Neuronal Apoptosis in Vascular Dementia Rats.

BACKGROUND: The purpose of this paper is to explore the mechanism of aerobic exercise regulating autophagy through the PI3K/Akt-mTOR signaling pathway and its participation in apoptosis, to protect the hippocampal nerves from damage in vascular dementia rats. METHODS: Thirty-six healthy male SD rats were randomly divided into a sham group, a model group, and a model exercise group. A neurobehavioral assessment was used to determine the memory and exploration abilities of the rats. A TUNEL assay was used to detect hippocampal neuron apoptosis. Immunohistochemical and Western blot analyses were used to analyze LC3Ⅱ and the beclin-1 protein. An RT-PCR detected the differential expression of mRNA. RESULTS: The results of the neurobehavioral tests showed that the platform latency time of the rats with vascular dementia was prolonged. Aerobic exercise significantly shortens the swimming time of rats in platform latency. The TUNEL results showed that the TUNEL-positive cells of the hippocampal neurons in the model group increased; the expression of pro-apoptotic genes caspase-3 and Bax mRNA was up-regulated, and the expression of Bcl-2 mRNA was down-regulated. Aerobic exercise reduced hippocampal neuronal apoptosis, up-regulated Bcl-2 mRNA, and down-regulated caspase-3 and Bax mRNA. The LC3Ⅱ and Beclin-1 proteins, detected by immunohistochemistry and a Western blot analysis, showed that the protein expression in the hippocampi of rats with vascular dementia increased. Aerobic exercise reduced LC3Ⅱ and Beclin-1 protein expression. The results of the RT-PCR showed similar changes. CONCLUSIONS: Aerobic exercise could improve the learning and memory abilities of vascular dementia rats, moderately regulate the process of autophagy, reduce the TUNEL-positive cells of hippocampal neurons, repair damaged hippocampal neurons by regulating the autophagy signaling pathway PI3K/Akt-mTOR, and improve hippocampal function.

Citrus NIP5;1 aquaporin regulates cell membrane water permeability and alters PIPs plasma membrane localization.

KEY MESSAGE: The ER or donut-like structures localized aquaporin NIP5;1, which interacts with PIPs and alters their localization from plasma membrane to donut-like structures, regulates water permeability. NOD26-like intrinsic proteins (NIPs) play important roles in nutrient uptake and response to various stresses. However, there have been few studies of their functions in water transportation in citrus. Here, we demonstrate the functions of a novel citrus NIP aquaporin (CsNIP5;1) via multiple physiological and biochemical experiments. CsNIP5;1 showed high water permeability when expressed in Xenopus laevis oocytes and yeast. However, subcellular localization assays showed that this protein was localized in the endoplasmic reticulum (ER) or donut-like structures in citrus callus and tobacco leaf. Meanwhile, overexpression of CsNIP5;1 led to a reduction in the water permeability of citrus callus. Protein-protein interaction experiments and subcellular localization assays further revealed that CsNIP5;1 physically interacted with PIPs (CsPIP1;1 and AtPIP2;1), which altered their subcellular localization from the plasma membrane to donut-like structures. Together, CsNIP5;1 was identified as a good water channel when expressed in oocytes and yeast. Meanwhile, CsNIP5;1 participated in the regulation of water permeability of citrus callus, which may be associated with CsNIP5;1-induced re-localization of water channels PIPs. In summary, these results provide new insights into the regulatory mechanism of AQPs-mediated water diffusion.