Lycium barbarum glycopetide prolong lifespan and alleviate Parkinson's disease in Caenorhabditis elegans

A review of Lycium barbarum polysaccharides: Extraction, purification, structural-property relationships, and bioactive molecular mechanisms

Lycium barbarum L. is of great significance medicinal and edible plant, which is native to N. & Central China. The extensive health benefits of L. barbarum have earned it great respect in traditional medicine for centuries. Lycium barbarum polysaccharides (LBPs) being recognized as one of the most crucial bioactive compounds found within this plant, with it exhibit a diverse range of pharmacological activities and nutritional functions, thereby generating substantial market demand and broad application prospects. To gain a more comprehensive understanding of LBPs, the review discussed the extraction, purification and structural-property relationships of these compounds. In addition, this review provides a comprehensive summary of the potential mechanisms underlying various biological activities attributed to LBPs, including immune modulation, antioxidant effects, neuroprotection, hepatoprotection, and antitumor properties. The application status and the future research directions of LBPs were subsequently presented. This review will establish a robust foundation and serve as an invaluable resource for future research and advancements in the field of LBPs.

Lycium barbarum glycopeptide promotes neuroprotection in ET-1 mediated retinal ganglion cell degeneration

BACKGROUND

Vascular dysregulation is one of the major risk factors of glaucoma, and endothelin-1 (ET-1) may have a role in the pathogenesis of vascular-related glaucoma. Fruit extract from Lycium Barbarum (LB) exhibits anti-ageing and multitarget mechanisms in protecting retinal ganglion cells (RGC) in various animal models. To investigate the therapeutic efficacy of LB glycoproteins (LbGP) in ET-1 induced RGC degeneration, LbGP was applied under pre- and posttreatment conditions to an ET-1 mouse model. Retina structural and functional outcomes were characterised using clinical-based techniques.

METHODS

Adult C57BL/6 mice were randomly allocated into four experimental groups, namely vehicle control (n = 9), LbGP-Pretreatment (n = 8), LbGP-Posttreatment (day 1) (n = 8) and LbGP-Posttreatment (day 5) (n = 7). Oral administration of LbGP 1 mg/Kg or PBS for vehicle control was given once daily. Pre- and posttreatment (day 1 or 5) were commenced at 1 week before and 1 or 5 days after intravitreal injections, respectively, and were continued until postinjection day 28. Effects of treatment on retinal structure and functions were evaluated using optical coherence tomography (OCT), doppler OCT and electroretinogram measurements at baseline, post-injection days 10 and 28. RGC survival was evaluated by using RBPMS immunostaining on retinal wholemounts.

RESULTS

ET-1 injection in vehicle control induced transient reductions in arterial flow and retinal functions, leading to significant RNFL thinning and RGC loss at day 28. Although ET-1 induced a transient loss in blood flow or retinal functions in all LbGP groups, LbGP treatments facilitated better restoration of retinal flow and retinal functions as compared with the vehicle control. Also, all three LbGP treatment groups (i.e. pre- and posttreatments from days 1 or 5) significantly preserved thRNFL thickness and RGC densities. No significant difference in protective effects was observed among the three LbGP treatment groups.

CONCLUSION

LbGP demonstrated neuroprotective effects in a mouse model of ET-1 induced RGC degeneration, with treatment applied either as a pretreatment, immediate or delayed posttreatment. LbGP treatment promoted a better restoration of retinal blood flow, and protected the RNFL, RGC density and retinal functions. This study showed the translational potential of LB as complementary treatment for glaucoma management.

Lycium barbarum glycopeptide ameliorates motor and visual deficits in autoimmune inflammatory diseases

BACKGROUND

Lycium barbarum glycopeptide (LbGp), extracted from the traditional Chinese medicine (TCM) of Lycium barbarum (LB), provides a neuroprotective effect against neurodegenerative and neuroimmune disorders contributing to its immunomodulatory and anti-inflammatory roles. Neuromyelitis optica spectrum disorders (NMOSD) is an autoimmune-mediated central nervous system (CNS) demyelinating disease, clinically manifested as transverse myelitis (TM) and optic neuritis. However, no drug has been demonstrated to be effective in relieving limb weakness and visual impairment of NMOSD patients.

PURPOSE

This study investigates the potential role of LbGp in ameliorating pathologic lesions and improving neurological dysfunction during NMOSD progression, and to elucidate the underlying mechanisms for the first time.

STUDY DESIGN

We administrate LbGp in experimental NMOSD models in ex vivo and in vivo to explore its effect on NMOSD.

METHODS

To evaluate motor function, both rotarod and gait tasks were performed in systemic NMOSD mice models. Furthermore, we assessed the severity of NMO-like lesions of astrocytes, organotypic cerebellar slices, as well as brain, spinal cord and optic nerve sections from NMOSD mouse models with LbGp treatment by immunofluorescent staining. In addition, demyelination levels in optic nerve were measured by G-ratio through Electro-microscopy (EM). And inflammation response was explored through detecting the protein levels of proinflammatory cytokines and NF-κB signaling in astrocytic culture medium and spinal cord homogenates respectively by Elisa and by Western blotting.

RESULTS

LbGp could significantly reduce astrocytes injury, demyelination, and microglial activation in NMOSD models. In addition, LbGp also improved locomotor and visual dysfunction through preventing neuron and retinal ganglion cells (RGCs) from inflammatory attack in a systemic mouse model. Mechanistically, LbGp inhibits proinflammatory factors release via inhibition of NF-κB signaling in NMOSD models.

CONCLUSION

This study provides evidence to develop LbGp as a functional TCM for the clinical treatment of NMOSD.

Paeonol promotes longevity and fitness in Caenorhabditis elegans through activating the DAF-16/FOXO and SKN-1/Nrf2 transcription factors

Paeonol, as one of the most abundant plant-derived polyphenols, has multiple bioactivities including anti-inflammatory, anti-tumor, and anti-cardiovascular diseases. Nevertheless, the anti-aging effects and related mechanisms of paeonol are rarely reported. In this study, we found that paeonol significantly prolonged the mean lifespan of Caenorhabditis elegans (C. elegans) by 28.49% at a dose of 200 μM. Moreover, paeonol promoted the health of C. elegans by increasing the body bending and pharyngeal pumping rates and reducing the lipofuscin accumulation level. Meanwhile, paeonol induced the expression of stress-related genes or proteins by activating the transcription factors DAF-16/FOXO, SKN-1/Nrf2, and HSF-1, which in turn enhanced oxidative and thermal stress tolerance. The mechanism behind the anti-aging effect of paeonol occurred by down-regulating the insulin/IGF-1 signaling (IIS) pathway. Our findings shed new light on the application of paeonol for longevity promotion and human health.

Melatonin derivative 6a as a PARP-1 inhibitor for the treatment of Parkinson's disease

Both continuous oxidative stress and poly (ADP-ribose) polymerase 1 (PARP-1) activation occur in neurodegenerative diseases such as Parkinson's disease. PARP-1 inhibition can reverse mitochondrial damage and has a neuroprotective effect. In a previous study, we synthesized melatonin derivative 6a (MD6a) and reported that it has excellent antioxidant activity and significantly reduces α-synuclein aggregation in Caenorhabditis elegans; however, the underlying mechanism is largely unknown. In the present study, we revealed that MD6a is a potential PARP-1 inhibitor, leading to mammalian targe of rapamycin/heat shock factor 1 signaling downregulation and reducing heat shock protein 4 and 6 expression, thus helping to maintain protein homeostasis and improve mitochondrial function. Together, these findings suggest that MD6a might be a viable candidate for the prevention and treatment of Parkinson's disease.

Hormesis determines lifespan

This paper addresses how long lifespan can be extended via multiple interventions, such as dietary supplements [e.g., curcumin, resveratrol, sulforaphane, complex phytochemical mixtures (e.g., Moringa, Rhodiola)], pharmaceutical agents (e.g., metformin), caloric restriction, intermittent fasting, exercise and other activities. This evaluation was framed within the context of hormesis, a biphasic dose response with specific quantitative features describing the limits of biological/phenotypic plasticity for integrative biological endpoints (e.g., cell proliferation, memory, fecundity, growth, tissue repair, stem cell population expansion/differentiation, longevity). Evaluation of several hundred lifespan extending agents using yeast, nematode (Caenorhabditis elegans), multiple insect and other invertebrate and vertebrate models (e.g., fish, rodents), revealed they responded in a manner [average (mean/median) and maximum lifespans] consistent with the quantitative features [i.e., 30-60% greater at maximum (Hormesis Rule)] of the hormetic dose response. These lifespan extension features were independent of biological model, inducing agent, endpoints measured and mechanism. These findings indicate that hormesis describes the capacity to extend life via numerous agents and activities and that the magnitude of lifespan extension is modest, in the percentage, not fold, range. These findings have important implications for human aging, genetic diseases/environmental stresses and lifespan extension, as well as public health practices and long-term societal resource planning.

Bioactive Components of Lycium barbarum and Deep-Processing Fermentation Products

Lycium barbarum, a homology of medicine and food, contains many active ingredients including polysaccharides, polyphenol, betaine, and carotenoids, which has health benefits and economic value. The bioactive components in Lycium barbarum exhibit the effects of antioxidation, immune regulation, hypoglycemic effects, and vision improvement. Recently, the development of nutrition and health products of Lycium barbarum has been paid more and more attention with the increase in health awareness. A variety of nutrients and bioactive components in wolfberry can be retained or increased using modern fermentation technology. Through fermentation, the products have better flavor and health function, which better meet the needs of market diversification. The main products related to wolfberry fermentation include wolfberry fruit wine, wolfberry fruit vinegar, and lactic acid fermented beverage. In this review, the mainly bioactive components of Lycium barbarum and its deep-processing products of fermentation were summarized and compared. It will provide reference for the research and development of fermented and healthy products of Lycium barbarum.