Natural products attenuate PI3K/Akt/mTOR signaling pathway: A promising strategy in regulating neurodegeneration.

BACKGROUND: As common, progressive, and chronic causes of disability and death, neurodegenerative diseases (NDDs) significantly threaten human health, while no effective treatment is available. Given the engagement of multiple dysregulated pathways in neurodegeneration, there is an imperative need to target the axis and provide effective/multi-target agents to tackle neurodegeneration. Recent studies have revealed the role of phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) in some diseases and natural products with therapeutic potentials. PURPOSE: This is the first systematic and comprehensive review on the role of plant-derived secondary metabolites in managing and/or treating various neuronal disorders via the PI3K/Akt/mTOR signaling pathway. STUDY DESIGN AND METHODS: A systematic and comprehensive review was done based on the PubMed, Scopus, Web of Science, and Cochrane electronic databases. Two independent investigators followed the PRISMA guidelines and included papers on PI3K/Akt/mTOR and interconnected pathways/mediators targeted by phytochemicals in NDDs. RESULTS: Natural products are multi-target agents with diverse pharmacological and biological activities and rich sources for discovering and developing novel therapeutic agents. Accordingly, recent studies have shown increasing phytochemicals in combating Alzheimer's disease, aging, Parkinson's disease, brain/spinal cord damages, depression, and other neuronal-associated dysfunctions. Amongst the emerging targets in neurodegeneration, PI3K/Akt/mTOR is of great importance. Therefore, attenuation of these mediators would be a great step towards neuroprotection in such NDDs. CONCLUSION: The application of plant-derived secondary metabolites in managing and/or treating various neuronal disorders through the PI3K/Akt/mTOR signaling pathway is a promising strategy towards neuroprotection.

The complete chloroplast genome of Stemona tuberosa Lour (Stemonaceae).

Stemona tuberosa Lour is a perennial herb in the family of Stemonaceae. It is commonly used as traditional medicine in China. Here, we assembled and annotated the complete chloroplast genome of S. tuberosa. The chloroplast genome was 154,374 bp in length, containing a typical quadripartite structure with a large single copy (LSC) of 82,305 bp, a small single copy (SSC) of 17,929 bp, and two inverted repeats (IRa and IRb) regions of 27,070 bp each. The overall GC content of the genome was 37.88%. A total of 134 genes were annotated in the chloroplast genome, including 88 protein-coding genes, 38 transfer RNA (tRNA) genes, and 8 ribosomal RNA (rRNA) genes. Phylogenetic analysis suggested that S. tuberosa was closely related to S. japonica and S. mairei.

The complete chloroplast genome of Polygonatum cirrhifolium (Wall.) Royle, a medicine herb.

Polygonatum cirrhifolium (Wall.) Royle is a medicinal plant of commercial value. In the present study, we assembled the complete chloroplast genome of P. cirrhifolium. The total genome was a circular DNA molecule of 155,583 bp, which was made up of a large single copy region (84,412 bp), a small single copy region (18,427 bp), and a pair of inverted repeat regions (26,372 bp each). A total of 133 genes was annotated in the chloroplast genome, including 85 protein-coding genes, 40 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. Overall, the chloroplast genome had a GC content of 37.66%. Phylogenetic analysis showed that P. cirrhifolium was closely related to P. kingianum.

Tribulus terrestris and female reproductive system health: A comprehensive review.

BACKGROUND: Tribulus terrestris L. (T. terrestris) positive performance on the male sexual system has been confirmed, but little is known about its effects on the female reproductive system. PURPOSE: This review discussed in detail the beneficial impact of T. terrestris and its secondary metabolites on the female reproductive system. STUDY DESIGN AND METHODS: In this review, the scientific Databases of Science direct, Pubmed, Web of Science, Google, Google Scholar, Researchgate, EMBASE, Scientific Information (SID), and Elsevier were searched profoundly. Studies about the pharmacological activities of T. terrestris on the female reproductive system in each aspect of investigations: human, in vivo, and in vitro studies, in the period from 1998 to 2020 were admitted. Our study was not limited by the language of publications. RESULTS: 23 articles about the effects of T. terrestris on the female reproductive system were found. These studies approved the T. terrestris efficacy on improvements in histological features of the ovary and uterus of polycystic ovary syndrome patients as well as the well-working of normal ovaries, enhancements in the sexual desire of postmenopausal syndrome, improve ovarian and breast cancers. CONCLUSION: These studies showed that the positive effect of T. terrestris on the female reproductive system was due to the presence of a secondary metabolite called protodioscin; a steroidal saponin compound, as the dominant active component of this plant.

Biotechnological Exploration of Transformed Root Culture for Value-Added Products.

Medicinal plants produce valuable secondary metabolites with anticancer, analgesic, anticholinergic or other activities, but low metabolite levels and limited available tissue restrict metabolite yields. Transformed root cultures, also called hairy roots, provide a feasible approach for producing valuable secondary metabolites. Various strategies have been used to enhance secondary metabolite production in hairy roots, including increasing substrate availability, regulating key biosynthetic genes, multigene engineering, combining genetic engineering and elicitation, using transcription factors (TFs), and introducing new genes. In this review, we focus on recent developments in hairy roots from medicinal plants, techniques to boost production of desired secondary metabolites, and the development of new technologies to study these metabolites. We also discuss recent trends, emerging applications, and future perspectives.

Polydatin effectively attenuates disease activity in lupus-prone mouse models by blocking ROS-mediated NET formation.

BACKGROUND: Neutrophil extracellular trap (NET) formation has been described to be closely involved in the pathogenesis of systemic lupus erythematosus (SLE). In this study, we aimed to investigate the effect of polydatin (PD) on NET formation and its effects on disease activity in lupus-prone mouse models. METHODS: In vitro, neutrophils from SLE patients and healthy people stimulated with phorbol 12-myristate 13-acetate (PMA) or phosphate-buffered saline (PBS) were treated with PD, and reactive oxygen species (ROS) production and NET formation examined. In vivo, pristane-induced lupus (PIL) mice were treated with vehicle, PD, mycophenolate mofetil (MMF) or cyclophosphamide (CYC) while MRL/lpr mice were treated with vehicle or PD. Proteinuria, serum autoantibodies, ROS production, NET formation and kidney histopathology were tested. RESULTS: Consistent with previous findings, blood neutrophils from SLE patients showed increased spontaneous NET formation. Both in vivo and in vitro, PD treatment significantly inhibited ROS production and NET release by neutrophils. In MRL/lpr mouse model, PD administration reduced the proteinuria, circulating autoantibody levels, and deposition of NETs and immune complex in the kidneys. In addition, PD treatment ameliorated lupus-like features in PIL mice as MMF or CYC did. CONCLUSIONS: PD treatment inhibited ROS-mediated NET formation and ameliorated lupus manifestations in both PIL mice and MRL/lpr mice. These results highlight the involvement of NETosis in SLE pathogenesis and reveal that PD might be a potential therapeutic agent for SLE or other autoimmune diseases.

Molecular cloning and characterization of two tropinone reductases in Anisodus acutangulus and enhancement of tropane alkaloid production in AaTRI-transformed hairy roots.

Tropane alkaloids are used medicinally as anticholinergic agents with increasing market demand, so the improvement and production of active components from medicinal plants using molecular biotechnology show great potential for applications that should benefit human healthcare. Two tropinone reductases constitute a branching point in the biosynthesis of tropane alkaloids. In the present paper, we report for the first time the cloning and characterization of two fulllength cDNAs encoding TRI (tropinone reductase I) (GenBank accession number EU424321) and TRII (tropinone reductase II) (GenBank(R) accession number EU424322) from the solanaceous plant Anisodus acutangulus by rapid amplification of cDNA ends. Sequence comparison indicated that AaTRI (A. acutangulus TRI) and AaTRII (A. acutangulus TRII) had high homology with other tropinone reductases from Hyoscyamus niger, Datura stramonium etc., but AaTRI and AaTRII showed identity of only 60.8%. Phylogenetic-tree analysis showed that AaTRI and AaTRII belong to different clusters and have the closest relationship with H. niger TRI and TRII respectively. Expression-pattern analysis showed that AaTRI and AaTRII were expressed in all tissues tested, including root, stem and leaf, but the transcript level of AaTRI was much lower than AaTRII. Expression of AaTRI and AaTRII could be enhanced by methyl jasmonate, with a weak effect for AaTRI and a strong effect for AaTRII. AaTRI-transformed hairy-root lines were accompanied by a mean 1.87-fold higher level of hyoscyamine and a mean 8-fold higher level of scopolamine compared with control roots, indicating that AaTRI is a promising target for genetic engineering to increase tropane alkaloid in A. acutangulus.