Alpinia oxyphylla Miq. fruit extract activates IGFR-PI3K/Akt signaling to induce Schwann cell proliferation and sciatic nerve regeneration

A critical appraisal on the involvement of plant-based extracts as neuroprotective agents (2012-2022): an effort to ease out decision-making process for researchers

The purpose of this review study is to provide a condensed compilation of 164 medicinal plants that have been investigated for their neuroprotective aspects by researchers between the years 2012 and 2022 which also includes a recent update of 2023-2024. After using certain keywords to retrieve the data from SCOPUS, it was manually sorted to eliminate any instances of duplication. The article is streamlined into three major segments. The first segment takes a dig into the current global trend and attempts to decrypt vital information related to plant names, families, plant parts used, and neurological disorders investigated. The second segment of the article makes an attempt to present a comprehensive insight into the various mechanistic pathways through which phytochemicals can intervene to exert neuroprotection. The final segment of the manuscript is a bibliometric appraisal of all researches conducted. The study is based on 256 handpicked articles based on decided inclusion criteria. Illustrative compilation of various pathways citing their activation and deactivation channels are also presented with possible hitting points of various phytochemicals. The present study employed Microsoft Excel 2019 and VOS viewer as data visualisation tools.

Andrographolide sensitizes KRAS-mutant colorectal cancer cells to cetuximab by inhibiting the EGFR/AKT and PDGFRβ/AKT signaling pathways

BACKGROUND

Cetuximab, an inhibitor targeting EGFR, is widely applied in clinical management of colorectal cancer (CRC). Nevertheless, drug resistance induced by KRAS-mutations limits cetuximab's anti-cancer effectiveness. Furthermore, the persistent activation of EGFR-independent AKT is another significant factor in cetuximab resistance. Nevertheless, the mechanism that EGFR-independent AKT drives cetuximab resistance remains unclear. Thus, highlighting the need to optimize therapies to overcome cetuximab resistance and also to explore the underlying mechanism.

PURPOSE

This work aimed to investigate whether and how andrographolide enhance the therapeutic efficacy of cetuximab in KRAS-mutant CRC cells by modulating AKT.

METHODS

The viabilities of CRC cell lines were analyzed by CCK-8. The intracellular proteins phosphorylation levels were investigated by Human Phospho-kinase Antibody Array analysis. Knockdown and transfection of PDGFRβ were used to evaluate the role of andrographolide on PDGFRβ. The western blotting was used to investigate Wnt/β-catenin pathways, PI3K/AKT, and EMT in KRAS-mutant CRC cells. The animal models including subcutaneous tumor and lung metastasis were performed to assess tumor response to therapy in vivo.

RESULTS

Andrographolide was demonstrated to decrease the expression of PI3K and AKT through targeting PDGFRβ and EGFR, and it enhanced cetuximab effect on KRAS-mutant CRC cells by this mechanism. Meanwhile, andrographolide helped cetuximab to inhibit Wnt/β-catenin, CRC cell migration and reduced Vimentin expression, while increasing that of E-cadherin. Lastly, co-treatment with cetuximab and andrographolide reduced the growth of KRAS-mutant tumors and pulmonary metastases in vivo.

CONCLUSIONS

Our findings suggest that andrographolide can overcome the KRAS-mutant CRC cells' resistance to cetuximab through inhibiting the EGFR/PI3K/AKT and PDGFRβ /AKT signaling pathways. This research provided a possible theory that andrographolide sensitizes KRAS-mutant tumor to EGFR TKI.

Silicone rubber sealed channel induced self-healing of large bone defects: Where is the limit of self-healing of bone?

Background

Large defects of long tubular bones due to severe trauma, bone tumor resection, or osteomyelitis debridement are challenging in orthopedics. Bone non-union and other complications often lead to serious consequences. At present, autologous bone graft is still the gold standard for the treatment of large bone defects. However, autologous bone graft sources are limited. Silicon rubber (SR) materials are widely used in biomedical fields, due to their safety and biocompatibility, and even shown to induce nerve regeneration.

Materials and methods

We extracted rat bone marrow mesenchymal stem cells (BMMSCs) in vitro and verified the biocompatibility of silicone rubber through cell experiments. Then we designed a rabbit radius critical sized bone defect model to verify the effect of silicone rubber sealed channel inducing bone repair in vivo.

Results

SR sealed channel could prevent the fibrous tissue from entering the fracture end and forming bone nonunion, thereby inducing self-healing of long tubular bone through endochondral osteogenesis. The hematoma tissue formed in the early stage was rich in osteogenesis and angiogenesis related proteins, and gradually turned into vascularization and endochondral osteogenesis, and finally realized bone regeneration.

Conclusions

In summary, our study proved that SR sealed channel could prevent the fibrous tissue from entering the fracture end and induce self-healing of long tubular bone through endochondral osteogenesis. In this process, the sealed environment provided by the SR channel was key, and this might indicate that the limit of self-healing of bone exceeded the previously thought.

The translational potential of this article

This study investigated a new concept to induce the self-healing of large bone defects. It could avoid trauma caused by autologous bone extraction and possible rejection reactions caused by bone graft materials. Further research based on this study, including the innovation of induction materials, might invent a new type of bone inducing production, which could bring convenience to patients. We believed that this study had significant meaning for the treatment of large bone defects in clinical practice.

In vitro bloodbrain barrier permeability study of four main active ingredients from Alpiniae oxyphyllae fructus

The fruits of Alpinia oxyphylla Miq., a broadly utilized traditional Chinese medicine, have a number of effects on the central nervous system (CNS). The main active constituents of Alpiniae oxyphyllae fructus (AOF) were nootkatone, tectochrysin, chrysin and protocatechuic acid. An immortalized human brain microvascular endothelial cell (hCMEC/D3) and astrocyte (HA1800) coculture model was used to investigate the permeability of the blood-brain barrier (BBB). The validation of ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) methods for the four compounds was conducted following industry guidelines. Calibration curves were generated with mean coefficients (R2) better than 0.99. The inter-day and intra-day precisions were less than 8.53% and 7.12%, respectively. The accuracies were lower than ± 11.57%, and recoveries were greater than 86.07%. The samples of the transport experiment were examined, and the apparent permeability coefficients (Papp) were calculated. The efflux ratios of the four compounds are all less than 2. The Papp values of protocatechuic acid, chrysin, nootkatone, tectochrysin were at the level of 10-5, 10-6, 10-6, and 10-7 cm/s, respectively. All four compounds crossed the BBB by passive diffusion, with protocatechuic acid having high permeability, and tectochrysin having poor permeability. This research indicated the permeability of protocatechuic acid, chrysin, nootkatone and tectochrysin through the BBB and offered a foundation for related research on AOF in the treatment of CNS illnesses.

Current and future outlook of loaded components in hydrogel composites for the treatment of chronic diabetic ulcers

Due to recalcitrant microangiopathy and chronic infection, traditional treatments do not easily produce satisfactory results for chronic diabetic ulcers. In recent years, due to the advantages of high biocompatibility and modifiability, an increasing number of hydrogel materials have been applied to the treatment of chronic wounds in diabetic patients. Research on composite hydrogels has received increasing attention since loading different components can greatly increase the ability of composite hydrogels to treat chronic diabetic wounds. This review summarizes and details a variety of newly loaded components currently used in hydrogel composites for the treatment of chronic diabetic ulcers, such as polymer/polysaccharides/organic chemicals, stem cells/exosomes/progenitor cells, chelating agents/metal ions, plant extracts, proteins (cytokines/peptides/enzymes) and nucleoside products, and medicines/drugs, to help researchers understand the characteristics of these components in the treatment of diabetic chronic wounds. This review also discusses a number of components that have not yet been applied but have the potential to be loaded into hydrogels, all of which play roles in the biomedical field and may become important loading components in the future. This review provides a "loading component shelf" for researchers of composite hydrogels and a theoretical basis for the future construction of "all-in-one" hydrogels.

TIMP1 derived from pancreatic cancer cells stimulates Schwann cells and promotes the occurrence of perineural invasion

Perineural invasion (PNI) occurs in most pancreatic ductal adenocarcinomas (PDACs). The relationship between cancer cells and peripheral nerves, however, is unknown. Therefore, we focused on the cooperation of PDAC cells and peripheral nerve astrocytes, Schwann cells (SCs), in PNI. The mutual tumor-supportive secretory cytokines between SCs (sNF96.2) and PDAC cells (PANC-1, BxPC-3) were screened by human cytokine arrays and verified. The prognostic value of selected cytokines and SC-associated markers was confirmed in PDAC patients. TIMP1 and CCL7 were found to form a paracrine feedback loop between PDAC cells and SCs. PDAC cell-derived TIMP1 promotes SCs proliferation and migration via CD63/PI3K/AKT signaling. CCL7 secreted from SCs enhances PDAC cell migration, invasion and expression of TIMP1 via CCR2/STAT3. PDAC cell-SC cooperation in PNI was blocked when TIMP1 knockdown in vitro and in vivo. Finally, TIMP1, CCL7 and SC-associated markers were correlated with PNI and prognosis in PDAC patients. In conclusion, SCs collaborate with PDAC cells through the TIMP1-CCL7 paracrine feedback loop to promote PNI. TIMP1 knockdown in PDAC cells suppresses PNI. Strategies to disrupt the TIMP1-CCL7 feedback loop might be developed to inhibit PNI in PDAC.

Alpiniae oxyphyllae fructus possesses neuroprotective effects on H2O2 stimulated PC12 cells via regulation of the PI3K/Akt signaling Pathway

Backgroud: Alzheimer’s disease (AD) is a typical neurodegenerative disease, which occurs in the elderly population. Alpiniae oxyphyllae Fructus (AOF) is a traditional Chinese medicine that has potential therapeutic effect on AD, but the mechanism behind it is unclear.

Methods: Firstly, the main chemical components of AOF were identified by LC-MS, while the main active ingredients and targets were screened by TCMSP database. At the same time, AD-related target proteins were obtained using Genecards and OMIM databases. PPI was constructed by cross-linking AOF and AD targets, and GO enrichment analysis and KEGG pathway enrichment analysis were performed to identify the relevant biological processes and signaling pathways. Finally, based on the H₂O₂-stimulated PC12 cell, flow cytometry, WB and immunofluorescence experiments were performed to verify the protective effect of AOF on AD.

Results: We identified 38 active ingredients with 662 non-repetitive targets in AOF, of which 49 were potential therapeutic AD targets of AOF. According to the GO and KEGG analysis, these potential targets are mainly related to oxidative stress and apoptosis. The role of AOF in the treatment of AD is mainly related to the PI3K/AKT signaling pathway. Protocatechuic acid and nootkatone might be the main active ingredients of AOF. In subsequent experiments, the results of CCK-8 showed that AOF mitigated PC12 cell damage induced by H₂O₂. Kits, flow cytometry, and laser confocal microscopy indicated that AOF could decrease ROS and increase the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), while AOF could also increase mitochondrial membrane potential (MMP), thereby inhibiting apoptosis. Finally, immunofluorescence and WB results showed that AOF inhibited the expression of BAX and caspase-3 in PC12 cells, and promoted the expression of Bcl-2. At the same time, the phosphorylation levels of PI3K and Akt proteins were also significantly increased.

Conclusion: This study suggests that AOF had the potential to treat AD by suppressing apoptosis induced by oxidative stress via the PI3K/Akt pathway.

Peripheral nerve defects repaired with autogenous vein grafts filled with platelet-rich plasma and active nerve microtissues and evaluated by novel multimodal ultrasound techniques

BACKGROUND

Developing biocompatible nerve conduits that accelerate peripheral nerve regeneration, lengthening and functional recovery remains a challenge. The combined application of nerve microtissues and platelet-rich plasma (PRP) provides abundant Schwann cells (SCs) and various natural growth factors and can compensate for the deficiency of SCs in the nerve bridge, as well as the limitations of applying a single type of growth factor. Multimodal ultrasound evaluation can provide additional information on the stiffness and microvascular flow perfusion of the tissue. This study was designed to investigate the effectiveness of a novel tissue-engineered nerve graft composed of an autogenous vein, nerve microtissues and PRP in reconstructing a 12-mm tibial nerve defect and to explore the value of multimodal ultrasound techniques in evaluating the prognosis of nerve repair.

METHODS

In vitro, nerve microtissue activity was first investigated, and the effects on SC proliferation, migration, factor secretion, and axonal regeneration of dorsal root ganglia (DRG) were evaluated by coculture with nerve microtissues and PRP. In vivo, seventy-five rabbits were equally and randomly divided into Hollow, PRP, Micro-T (Microtissues), Micro-T + PRP and Autograft groups. By analysing the neurological function, electrophysiological recovery, and the comparative results of multimodal ultrasound and histological evaluation, we investigated the effect of these new nerve grafts in repairing tibial nerve defects.

RESULTS

Our results showed that the combined application of nerve microtissues and PRP could significantly promote the proliferation, secretion and migration of SCs and the regeneration of axons in the early stage. The Micro-T + PRP group and Autograft groups exhibited the best nerve repair 12 weeks postoperatively. In addition, the changes in target tissue stiffness and microvascular perfusion on multimodal ultrasound (shear wave elastography; contrast-enhanced ultrasonography; Angio PlaneWave UltrasenSitive, AngioPLUS) were significantly correlated with the histological results, such as collagen area percentage and VEGF expression, respectively.

CONCLUSION

Our novel tissue-engineered nerve graft shows excellent efficacy in repairing 12-mm defects of the tibial nerve in rabbits. Moreover, multimodal ultrasound may provide a clinical reference for prognosis by quantitatively evaluating the stiffness and microvescular flow of nerve grafts and targeted muscles.

Dietary biomolecules as promising regenerative agents for peripheral nerve injury: An emerging nutraceutical-based therapeutic approach

Peripheral nerve damage is a debilitating condition that can result in partial or complete functional loss as a result of axonal degeneration, as well as lifelong dependence. Many therapies have been imbued with a plethora of positive features while posing little risks. It is worth noting that these biomolecules work by activating several intrinsic pathways that are known to be important in peripheral nerve regeneration. Although the underlying mechanism is used for accurate and speedy functional recovery, none of them are without side effects. As a result, it is believed that effective therapy is currently lacking. The dietary biomolecules-based intervention, among other ways, is appealing, safe, and effective. Upregulation of transcription factors, neurotrophic factors, and growth factors such as NGF, GDNF, BDNF, and CTNF may occur as a result of these substances' dietary intake. Upregulation of the signaling pathways ERK, JNK, p38, and PKA has also been seen, which aids in axonal regeneration. Although several mechanistic approaches to understanding their involvement have been suggested, more work is needed to reveal the amazing properties of these biomolecules. We have discussed in this article that how different dietary biomolecules can help with functional recovery and regeneration after an injury. PRACTICAL APPLICATIONS: Based on the information known to date, we may conclude that treatment techniques for peripheral nerve injury have downsides, such as complications, donor shortages, adverse effects, unaffordability, and a lack of precision in efficacy. These difficulties cast doubt on their efficacy and raise severe concerns about the prescription. In this situation, the need for safe and effective therapeutic techniques is unavoidable, and dietary biomolecules appear to be a safe, cost-efficient, and effective way to promote nerve regeneration following an injury. The information on these biomolecules has been summarized here. Upregulation of transcription factors, neurotrophic factors, and growth factors, such as NGF, GDNF, BDNF, and CTNF, as well as the ERK, JNK, p38, and PKA, signaling pathways, may stimulate axonal regeneration.

Revisiting the Role of Biologically Active Natural and Synthetic Compounds as an Intervention to Treat Injured Nerves

Traumatic lesions in nerves present high incidence and may culminate in sensorimotor and/or autonomic dysfunctions or a total loss of function, affecting the patient's quality of life. Although the microenvironment favors peripheral nerve regeneration, the regenerative process is not always successful. Some herbs, natural products, and synthetic drugs have been studied as potential pro-regenerative interventions. We reviewed and discussed the most recent articles published over the last ten years in high impact factor journals. Even though most of the articles contemplated in this review were in vitro and animal model studies, those with herbs showed promising results. Most of them presented antioxidant and anti-inflammatory effects. Drugs of several pharmacological classes also showed optimistic outcomes in nerve functional recovery, including clinical trials. The results are hopeful; however, mechanisms of action need to be elucidated, and there is a need for more high-quality clinical studies. The study presents careful compilation of findings of dozens of compounds with consistent pro-regenerative evidence published in respected scientific journals. It may be valuable for health professionals and researchers in the field.

Photobiomodulation enhances facial nerve regeneration via activation of PI3K/Akt signaling pathway-mediated antioxidant response

Facial nerve dysfunction is a common clinical condition that leads to disfigurement and emotional distress in the affected individuals. This study aimed to evaluate whether photobiomodulation can enhance regeneration of crushed facial nerves and attempt to investigate the possible underlying mechanism of neuroprotective function and therapeutic target. Various parameters of photobiomodulation were assigned to the facial nerves and Schwann cells (SCs) separately during crushed injury in rats. Axonal regeneration, functional outcomes, and SC apoptosis, proliferation, and underlying mechanisms of action were evaluated by morphological, histopathological, and functional assessments, flow cytometry, western blotting, real-time PCR, and IncuCyte. The results showed that photobiomodulation improved axonal regeneration and functional recovery, and also promoted proliferation, and inhibited apoptosis of SCs, both of these were considered as the most effective parameters in 250mW group. In addition, the neuroprotective effects of photobiomodulation (500mW) were likely associated with oxidative stress-induced SC apoptosis via activation of the PI3K/Akt signaling pathway. Our results revealed that photobiomodulation significantly promoted axonal regeneration, functional recovery, and regeneration of the facial nucleus, and its mechanism was related to the up-regulation of the PI3K/Akt signaling pathway. These findings provide clear experimental evidence of photobiomodulation as an alternative therapeutic strategy for peripheral nerve damage.

Insulin-Like Growth Factor-1: A Promising Therapeutic Target for Peripheral Nerve Injury

Patients who sustain peripheral nerve injuries (PNIs) are often left with debilitating sensory and motor loss. Presently, there is a lack of clinically available therapeutics that can be given as an adjunct to surgical repair to enhance the regenerative process. Insulin-like growth factor-1 (IGF-1) represents a promising therapeutic target to meet this need, given its well-described trophic and anti-apoptotic effects on neurons, Schwann cells (SCs), and myocytes. Here, we review the literature regarding the therapeutic potential of IGF-1 in PNI. We appraised the literature for the various approaches of IGF-1 administration with the aim of identifying which are the most promising in offering a pathway toward clinical application. We also sought to determine the optimal reported dosage ranges for the various delivery approaches that have been investigated.

Integrated UPLC-MS/MS and UHPLC-Q-orbitrap HRMS Analysis to Reveal Pharmacokinetics and Metabolism of Five Terpenoids from Alpiniae oxyphyllae Fructus in Rats

BACKGROUND

Alpiniae oxyphyllae Fructus (AOF), a traditional Chinese medicine (TCM), is widely used in the treatment of urinary, gastrointestinal and neurologic diseases in China. Although terpenoids are the main active ingredients of AOF, there are few researches on their pharmacokinetics and metabolism.

METHODS

In this study, a sensitive, rapid, accurate and novel ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established to evaluate the pharmacokinetic behavior of five terpenoids (oxyphyllenodiol B, (4S*,5E,10R*)-7-oxo-tri-nor-eudesm-5-en-4β-ol, 7-epi-teucrenone, (+)- (4R,5S,7R)-13-hydroxynootkatone, (E)-labda-12,14-dien-15(16)-olide-17-oic acid) in rats after oral administration of AOF extracts. 27 metabolic metabolites of the five terpenoids were identified by ultra high performance liquid chromatography -Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Q-Orbitrap HRMS) based on precise mass and fragment ions.

RESULTS

The established pharmacokinetic analysis method showed good linearity over a wide concentration range, and the lower quantitative limit (LLOQ) ranged from 0.97 to 4.25 ng/mL. Other validation parameters were within the acceptable range. In addition, 27 metabolites were identified in plasma, urine and feces samples, and the metabolic pathways of five terpenoids were mainly focused on glucoside conjugation, dehydration, desaturation and glycine conjugation.

CONCLUSION

This is the first study on the pharmacokinetics and metabolism of five terpenoids in AOF, illuminating the disposal process of terpenoids in vivo. It was expected that the results of this study would provide some references for the apprehension of the action mechanism and the further pharmacological study of five terpenoids in AOF.

D-galactose-induced toxicity associated senescence mitigated by alpinate oxyphyllae fructus fortified adipose-derived mesenchymal stem cells

This study addresses the effect of D-galactose-induced toxicity associated senescence mitigated by alpinate oxyphyllae fructus (AOF; Alpinia oxyphylla Miq) extracts fortified with adipose-derived mesenchymal stem cells (ADMSCs) in rats. Male 18 week-old Wistar Kyoto (WKY) rats were used in this study. We analyzed cardiac fibrosis by Masson's trichrome staining. The tissue sections were dyed using hematoxylin and eosin (H&E). Tissue sections were stained for the restoration of Nrf2 expression in treatment groups by immunohistochemistry. Immunohistochemistry and western blotting analysis showed that AOF with ADMSCs could significantly reduce aging-induced oxidative stress in D-galactose-induced aging rat hearts by inducing Nrf2 pathway. Reduction in ROS resulted in the suppression of inflammatory signals (p-NF-κB and IL-6). Histopathological studies were showed an increased interstitium and collagen accumulation in aging-induced heart sections. However, AOF and ADMSCs treated hearts were recovered from cardiac remodeling. Furthermore, hypertrophy and fibrosis associated markers were also significantly reduced (P < .05) in treatment groups. We speculate that ADMSCs might activate certain paracrine factors, which could target the upstream activator of aging associated cardiac complications and AOF might provide homing for these stem cells.

Alpiniae oxyphyllae Fructus and Alzheimer's disease: An update and current perspective on this traditional Chinese medicine

Alzheimer's disease (AD) is a common progressive neuro-degenerative disease, and the morbidity and mortality are still on the rise. In spite of recent advances in AD treatment, their clinical efficacy has been limited, non-curative and easy to drug resistance. Alpiniae oxyphyllae Fructus (AOF), derived from the dried and mature fruits of the Zingiberaceae plant Alpinia oxyphylla Miq, is a choice in traditional Chinese medicine to treat AD, which has a good effect and has been used for a long time. Recent studies have demonstrated its potent activities in modulating multiple signaling pathways associated with β-amyloid deposition, tau protein phosphorylation, chronic inflammation, oxidative stress. The neuropharmacological mechanism of AOF in AD have been fully illustrated in numerous studies. In this review, we first briefly described the active components of AOF and related mechanism for treating AD. And we also provide a systematic overview of recent progress on the pharmacokinetic characteristics of the active ingredients of AOF and analyzed their bioavailability differences in the development of AD. Thus, AOF hold a great therapeutic potential in the treatment of AD and is worthy of further research and promotion.

Traditional Korean herbal formulae, Yuk-Mi-Ji-Hwang-Tang, ameliorates impairment of hippocampal memory ability by chronic restraint stress of mouse model

ETHNOPHARMACOLOGICAL RELEVANCE

Yuk-Mi-Jihwang-Tang (YJT) has been popularly prescribed to treat aging related disorders over than hundreds of years in East Asia countries.

AIM OF THE STUDY

To investigate possible modulatory actions of YJT on chronic restraint stress (CRS)-induced neurodegeneration on hippocampus neuronal injuries.

MATERIALS AND METHODS

Mice were orally administered with YJT (100, 200, or 400 mg/kg) or ascorbic acid (100 mg/kg) before 4 h of stress for 28 days. Morris water maze task was completed from day 24th to 28th, and stress hormones and biochemical analyzes were measured.

RESULTS

Four weeks of the CRS abnormally affected memory impairments by measurement of escape latency and time spent in the target quadrant. Additionally, neurotransmitters were also drastically altered in serum or hippocampus protein levels by CRS. Gene expressions for 5-hydroxytryptamine (5-HT) receptor, 5-HT-transport, and tryptophan hydroxylase were also altered, whereas YJT led to normalize the above alterations. Additionally, YJT also beneficially worked on endogenous redox system as well as inflammatory reactions in the hippocampal neurons. We observed that hippocampal excitotoxicity was induced by CRS which were evidenced by depletion of phosphor-cAMP response element-binding protein, brain-derived neurotrophic factor, nuclear factor erythroid-2-related factor 2, heme oxygenase-1 and abnormally increases of acetylcholine esterase activities in hippocampus protein levels; however, YJT considerably improved the above pathological conditions.

CONCLUSIONS

Our findings supported YJT enhance memory function via regulation of hippocampal excitotoxicity-derived memory impairment, stress hormone, and endogenous redox, respectively.

Effects of NP-1 on proliferation, migration, and apoptosis of Schwann cell line RSC96 through the NF-κB signaling pathway

Peripheral nerve injury is a common refractory disease in the clinic that often leads to dysfunction of movement and sensation. Different from other tissue injuries, peripheral nerve injury needs a longer time for regeneration. Therefore, effective drug therapy is needed to promote nerve regeneration in the treatment of peripheral nerve injury. Our preliminary studies have shown that continuous intramuscular injection of NP-1 promotes the regeneration of injured sciatic nerve in rats, but the mechanisms were still unknown. Schwann cells are very important cells in the formation of myelin sheath of peripheral nerves and participate in the repair and regeneration of peripheral nerve injury. To further investigate the effect of NP-1 on rat Schwann cells and the underlying mechanism, different concentrations of NP-1 were used to treat rat Schwann cell line RSC96. Light microscopy, CCK-8 assay, cell scratch assay, and special cell staining were performed to investigate RSC96 cell aging and apoptosis. mRNA and protein expression of NF-κB signaling pathway-related factors were determined using qPCR and immunohistochemistry respectively. Light microscopy, CCK-8 assay, cell scratch assay, and special cell staining showed NP-1 could improve the ability of proliferation, immigration of Schwann cells. QPCR and immunohistochemistry showed NP-1 influenced the expression of multiple factors associated with nerve regeneration which NF-κB signaling pathway played a key role. The results show that NP-1 promoted the proliferation and migration of RSC96 cells and inhibited cell aging and apoptosis possibly through the NF-κB signaling pathway. These findings provide a potential target for clinical treatment of peripheral neuropathy and experimental data support.

Pharmacological Mechanisms Underlying the Neuroprotective Effects of Alpinia oxyphylla Miq. on Alzheimer's Disease

Alpinia oxyphylla Miq. (i.e., A. oxyphylla), a traditional Chinese medicine, can exert neuroprotective effects in ameliorating mild cognitive impairment and improving the pathological hallmarks of Alzheimer's disease (AD). Here, 50 active compounds and 164 putative targets were collected and identified with 251 clinically tested AD-associated target proteins using network pharmacology approaches. Based on the Gene Ontology/Kyoto Encyclopedia of Genes and Genomes pathway enrichments, the compound-target-pathway-disease/protein-protein interaction network constructions, and the network topological analysis, we concluded that A. oxyphylla may have neuroprotective effects by regulating neurotransmitter function, as well as brain plasticity in neuronal networks. Moreover, closely-related AD proteins, including the amyloid-beta precursor protein, the estrogen receptor 1, acetylcholinesterase, and nitric oxide synthase 2, were selected as the bottleneck nodes of network for further verification by molecular docking. Our analytical results demonstrated that terpene, as the main compound of A. oxyphylla extract, exerts neuroprotective effects, providing new insights into the development of a natural therapy for the prevention and treatment of AD.

Alpinia oxyphylla-Schisandra chinensis Herb Pair Alleviates Amyloid-β Induced Cognitive Deficits via PI3K/Akt/Gsk-3β/CREB Pathway

Alzheimer's disease (AD), one of the most common neurodegenerative diseases, threatens people's health. Based on the theory of traditional Chinese medicine (TCM) efficacy and treatment theory, we first proposed the Alpinia oxyphylla-Schisandra chinensis herb pair (ASHP) for finding a candidate of AD treatment. This study aimed at exploring the effects of ASHP on improving the cognitive function and neurodegeneration, and revealing the possible mechanism. In this study, an amyloid-β (Aβ) induced AD model was established in mice via intracerebroventricular injection. The Y-maze test and Morris water maze test were carried out to observe the behavioral change of mice, which showed that ASHP significantly ameliorated cognitive impairment. In addition, ASHP reduced amyloid-β deposition and downregulated the hyperphosphorylation of tau via immunofluorescence assay and western blot analysis, respectively. Subsequently we focused on the PI3K/Akt pathway that is a classical pathway related to nervous system diseases. It also noticeably ASHP improved the histopathological changes in the hippocampus and cortex. Moreover, it was found that ASHP could upregulate the PI3K/Akt/Gsk-3β/CREB signaling pathway in N2a-SwedAPP cells. Taken together, it suggests that ASHP might reverse cognitive deficits and neurodegeneration via PI3K/Akt/Gsk-3β/CREB pathway.

Involvement of PDGF-BB and IGF-1 in Activation of Human Schwann Cells by Platelet-Rich Plasma

BACKGROUND

Platelet-rich plasma contains high concentrations of growth factors that stimulate proliferation and migration of various cell types. Earlier experiments demonstrated that local platelet-rich plasma administration activates Schwann cells to improve axonal regeneration at a transected peripheral nerve lesion. However, the optimal concentration of human platelet-rich plasma for activation of human Schwann cells has not been determined, and mechanisms by which platelet-rich plasma activates Schwann cells remain to be clarified.

METHODS

Human Schwann cells were cultured with various concentrations of platelet-rich plasma in 5% fetal bovine serum/Dulbecco's Modified Eagle Medium. Cell viability, microchemotaxis, flow cytometry, and quantitative real-time polymerase chain reaction assays were performed to assess proliferation, migration, cell cycle, and neurotrophic factor expression of the human Schwann cells, respectively. Human Schwann cells were co-cultured with neuronal cells to assess their capacity to induce neurite extension. Neutralizing antibodies for platelet-derived growth factor-BB (PDGF-BB) and insulin-like growth factor-1 (IGF-1) were added to the culture to estimate contribution of these cytokines to human Schwann cell stimulation by platelet-rich plasma.

RESULTS

An addition of platelet-rich plasma at 5% strongly elevated proliferation, migration, and neurotrophic factor production of human Schwann cells. Both PDGF-BB and IGF-1 may be involved in mitogenic effect of platelet-rich plasma on human Schwann cells, and PDGF-BB may also play an important role in the migration-inducing effect of platelet-rich plasma. Neutralization of both PDGF-BB and IGF-1 cancelled the promoting effect of platelet-rich plasma on neurite-inducing activity of human Schwann cells.

CONCLUSION

This study may suggest the optimal concentration of platelet-rich plasma for human Schwann cell stimulation and potential mechanisms underlying the activation of human Schwann cells by platelet-rich plasma, which may be quite useful for platelet-rich plasma therapy for peripheral nerve regeneration.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, V.

The complete chloroplast genome sequence of Alpinia oxyphylla Miq. and comparison analysis within the Zingiberaceae family

Alpinia oxyphylla Miq. (A. oxyphylla) is an important edible and traditional herbal medicine. In this study, the complete chloroplast genome of A. oxyphylla was sequenced, analysed, and compared to five species in the Zingiberaceae family. The size of the A. oxyphylla chloroplast genome was 161351 bp, which consisted of a large single-copy (LSC, 87248 bp) and small single-copy (SSC, 16175 bp) region separated by a pair of inverted repeats (IRa and IRb, 28964 bp each). The genome encoded 132 unique genes, including 87 protein-coding genes, 37 tRNAs and four rRNAs. The GC content of the genome was 36.17%. A total of 53 simple sequence repeats (SSRs) and 80 long repeats were identified in the A. oxyphylla chloroplast genome. The chloroplast genome of A. oxyphylla shared the highest sequence similarity of >90% with the chloroplast genome of A. zerumbet, and six chloroplast genomes in the Zingiberaceae family were compared by using CGView Comparison Tool (CCT). According to the phylogenetic tree, the Zingiberaceae family is divided into two categories, which coincide with the classification of the characteristics of sun-like and shade-like in plants. Our results reveal the phototrophic component of NADH-dehydrogenase (ndhB and ndhC), photosystem II (psbZ) and ATP synthase (atpE, atpF) exhibit adaptive evolution under different environments, and the strength of light is an important trigger for the adaptations at the chloroplast level.

Proteomics analysis of Schwann cell-derived exosomes: a novel therapeutic strategy for central nervous system injury

Exosomes are nanometer-sized vesicles involved in intercellular communication, and they are released by various cell types. To learn about exosomes produced by Schwann cells (SCs) and to explore their potential function in repairing the central nervous system (CNS), we isolated exosomes from supernatants of SCs by ultracentrifugation, characterized them by electron microscopy and immunoblotting and determined their protein profile using proteomic analysis. The results demonstrated that Schwann cell-derived exosomes (SCDEs) were, on average, 106.5 nm in diameter, round, and had cup-like concavity and expressed exosome markers CD9 and Alix but not tumor susceptibility gene (TSG) 101. We identified a total of 433 proteins, among which 398 proteins overlapped with the ExoCarta database. According to their specific functions, we identified 12 proteins that are closely related to CNS repair and classified them by different potential mechanisms, such as axon regeneration and inflammation inhibition. Gene Oncology analysis indicated that SCDEs are mainly involved in signal transduction and cell communication. Biological pathway analysis showed that pathways are mostly involved in exosome biogenesis, formation, uptake and axon regeneration. Among the pathways, the neurotrophin, PI3K-Akt and cAMP signaling pathways played important roles in CNS repair. Our study isolated SCDEs, unveiled their contents, presented potential neurorestorative proteins and pathways and provided a rich proteomics data resource that will be valuable for future studies of the functions of individual proteins in neurodegenerative diseases.

Ethnopharmacological uses, phytochemistry, biological activities, and therapeutic applications of Alpinia oxyphylla Miquel: A review

ETHNOPHARMACOLOGICAL USAGES

Fructus Alpiniae oxyphyllae (A. oxyphylla) is an important medicinal plant that is used not only as an edible fruit, but also as an important traditional medicine for benefiting cognitive performance and alleviating a wide spectrum of diseases. Such as; warming kidney, securing essence and arresting polyuria, as well as warming the spleen and stopping diarrhea and saliva.

AIMS

The purpose of this review is to provide updated, comprehensive and categorized information on the traditional uses, phytochemistry and pharmacological research of A. oxyphylla in order to explore their therapeutic potential and establish a solid foundation for directing future research.

MATERIALS AND METHODS

All the available information on A. oxyphylla was collected via electronic search (using Pubmed, SciFinder, Scirus, Google Scholar and Web of Science) and additionally a number of unpublished resources, (e.g. books, Ph.D. and M.Sc. dissertations, government reports).

RESULTS

Phytochemical research on A. oxyphylla has led to the isolation of components such as essential oils, terpenes, diarylheptanoids, flavones, nucleobases and nucleosides, steroids and others. Crude extracts, fractions and phytochemical constituents isolated from A. oxyphylla showed a wide spectrum of in vitro and in vivo pharmacological activities like neuroprotective, anti-diarrheal, anti-diuretic, anti-neoplastic, anti-oxidant, anti-inflammatory, anti-allergic, viscera protective and anti-diabetic activities. Neuroprotective, anti-cancer, anti-diarrheal and anti-diuretic effects are major areas of research conducted on A. oxyphylla.

CONCLUSIONS

Modern pharmacological studies have supported many traditional uses of A. oxyphylla, including nervous system, urinary system and gastrointestinal system disease. There was convincing evidence in experimental animal models in support of its neuroprotection, secure essence, reduce urination, and anti-carcinogenic effects. However, all the reported pharmacological activities were carried out at pre-clinical level and the authors urge further investigation in clinical trials about these therapeutic fields of A. oxyphylla.

Berberine promotes nerve regeneration through IGFR‑mediated JNK‑AKT signal pathway

Berberine presents therapeutic ability for various central nervous system disorders, including Alzheimer's disease and cerebral ischemia. The present study investigated the role of berberine in nerve regeneration and analyzed the potential mechanism mediated by berberine in hippocampal pyramidal neurons. Reverse transcription-quantitative poylmerase chain reaction, western blot, TUNEL assay and immunofluorescence were used to analyze the therapeutic effects of berberine on nerve regeneration. Berberine treatment increased growth and viability of hippocampal pyramidal neurons. Berberine treatment inhibited apoptosis of hippocampal pyramidal neurons and increased apoptosis regulator Bcl-2 and Bcl-w expression. Neuroinflammation of tumor necrosis factor α, interleukin (IL)1β, IL6 levels and autophagy-related proteins microtubule-associated proteins 1A/1B light chain 3B, autophagy related 16 like 1 and autophagy related 7 were downregulated by berberine treatment in hippocampal pyramidal neurons. Notably, study has found that berberine increased insulin-like growth factor receptor (IGFR) and decreased c-Jun N-terminal kinase (JNK) and protein kinase B (AKT) expression in hippocampal pyramidal neurons. IGFR antagonist abolished berberine-increased growth of hippocampal pyramidal neurons. In conclusion, these results indicate that berberine can promote nerve regeneration through IGFR-mediated JNK-AKT signal pathway.

Up-Regulation of Cdc37 Contributes to Schwann Cell Proliferation and Migration After Sciatic Nerve Crush

Cell division cycle protein 37 (Cdc37), a molecular chaperone takes part in a series of cellular processes including cell signal transduction, cell cycle progression, cell proliferation, cell motility, oncogenesis and malignant progression. It can not only recruit immature protein kinases to HSP90 but also work alone. Cdc37 was reported to be associated with neurogenesis, neurite outgrowth, axon guidance and myelination. However, the roles of Cdc37 on Schwann cells (SC) after peripheral nerve injury (PNI) remain unknown. In this study, we found that the expression of Cdc37 increased and reached the peak at 1 week after sciatic nerve crush (SNC), which was consistent with that of proliferation cell nuclear antigen. Immunofluorescence verified that Cdc37 co-localized with SC in vivo and in vitro. Intriguingly, Cdc37 protein level was potentiated in the model of TNF-α-induced SC proliferation. Moreover, we found that Cdc37 silencing impaired proliferation of SC in vitro. Moreover, Cdc37 suppression attenuated kinase signaling pathways of Raf-ERK and PI3K/AKT which are crucial cell signaling for SC proliferation. Finally, we found that Cdc37 silencing inhibited SC migration in vitro. In conclusion, we demonstrated that the way Cdc37 contributed to SC proliferation is likely via activating kinase signaling pathways of Raf-ERK and PI3K/AKT, and CDC37 was also involved in SC migration after SNC.

Ginsenoside Rg1 protects human renal tubular epithelial cells from lipopolysaccharide-induced apoptosis and inflammation damage

Ginsenoside Rg1, one of the most notable active components of Panax ginseng, has been widely reported to exert anti-inflammatory actions. This study aimed to reveal whether ginsenoside Rg1 also exhibits beneficial roles against lipopolysaccharide (LPS)-induced apoptosis and inflammation in human renal tubular epithelial cells, and to evaluate the potential role of the component on tubulointerstitial nephritis treatment. HK-2 cells were treated with various doses of ginsenoside Rg1 (0, 50, 100, 150, and 200 μM) in the absence or presence of 5 μg/mL LPS. Thereafter, CCK-8 assay, flow cytometry, western blot, migration assay, reactive oxygen species (ROS) assay, and ELISA were carried out to respectively assess cell viability, apoptosis, migration, ROS activity, and the release of inflammatory cytokines. As a result, ginsenoside Rg1 protected HK-2 cells from LPS-induced injury, as cell viability was increased, cell apoptosis was decreased, and the release of MCP-1, IL-1β, IL-6, and TNF-α was reduced. Ginsenoside Rg1 functioned to HK-2 cells in a dose-dependent manner, and the 150 μM dose exhibited the most protective functions. Ginsenoside Rg1 had no significant impact on cell migration and ROS activity, while it alleviated LPS-induced ROS release and migration impairment. Furthermore, the down-regulations of p-PI3K, p-AKT, and up-regulations of PTEN, p-IκBα, p-p65, Bcl-3 induced by LPS were recovered to some extent after ginsenoside Rg1 treatment. In conclusion, ginsenoside Rg1 protects HK-2 cells against LPS-induced inflammation and apoptosis via activation of the PI3K/AKT pathway and suppression of NF-κB pathway.