Biological Activities of Snowdrop (Galanthus spp., Family Amaryllidaceae)

Alkaloid Profile, Anticholinesterase and Antioxidant Activities, and Sexual Propagation in Hieronymiella peruviana (Amaryllidaceae)

Hieronymiella peruviana, a recently described endemic species from southern Peru, belongs to the Amaryllidaceae family and is known for its diversity of alkaloids. Amaryllidoideae have been studied for their diverse biological activities, particularly for their properties in treating neurodegenerative diseases. This work examines the alkaloidal profile using GC-MS and UPLC-MS/MS of alkaloid-enriched extracts obtained from the leaves and bulbs of H. peruviana and their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. In addition, the phenolic and flavonoid content in the methanolic extract from bulbs was quantified and the antioxidant capacity was evaluated. Moreover, the seed germination was investigated under four temperature conditions (15, 20, 25, and 30 °C). Twenty-two alkaloids, most of them of the homolycorine- and galanthamine-type, including galanthamine, were identified in the alkaloid extracts by means of GC-MS and UPLC-MS/MS analysis. Lycorine and 8-O-Demethylhomolycorine were the most abundant alkaloids in the bulbs and leaves, respectively. The leaves and bulbs alkaloid extracts demonstrated strong AChE inhibition (IC50 = 5.20-8.60 µg/mL) and moderate BuChE inhibition (IC50 = 90.20-122.76 µg/mL). The bulbs' methanolic extract exhibited mild antioxidant activity, showing 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) values of 16.36% at 500 μg/mL and 58.31 mg Trolox equivalents (TE)/g, respectively. Seed germination was most effective at 20 °C and 25 °C. Finally, 60 days after germination, the survival rate of H. peruviana seedlings was 48.33%. These findings establish H. peruviana as a promising source of bioactive alkaloids with potential pharmacological and therapeutic applications, as well as providing critical insights for its propagation and conservation.

Biomacromolecules as Immunomodulators: Utilizing Nature’s Tools for Immune Regulation

Although there are numerous available immunomodulators, those of natural origin would be preferable based on their safety profile and effectiveness. The research and clinical interest in immunomodulators have increased in the last decades, especially in the immunomodulatory properties of plant-based therapies. Innovative technologies and extensive study on immunomodulatory natural products, botanicals, extracts, and active moieties with immunomodulatory potential could provide us with valuable entities to develop as novel immunomodulatory medicines to enhance current chemotherapies. This review focuses on plant-based immunomodulatory drugs that are currently in clinical studies. However, further studies in this area are of utmost importance to obtain complete information about the positive effects of medicinal plants and their chemical components and molecules as an alternative to combatting various diseases and/or prevention.

Anti-inflammatory effects of the plant family Amaryllidaceae

ETHNOPHARMACOLOGICAL RELEVANCE

Members of the plant family Amaryllidaceae are widely recorded in traditional systems of medicine. Their usage for inflammatory conditions is most prominent, with substantive evidence emerging from several locations around the world.

AIM OF THE STUDY

This survey was undertaken to identify such plant taxa, highlight the countries from which they originate and afford details of the ailments against which they are utilized. The undertaking also sought to establish the in vitro and in vivo activities of Amaryllidaceae plant extracts in inflammation-based assays. Furthermore, it set out to unravel the molecular mechanisms used to explain these effects.

MATERIALS AND METHODS

Over six-hundred articles were identified in searches carried out on SciFinder, Scopus, ScienceDirect, PubMed and Google Scholar. These were condensed to around 170 that formulated the basis of the text. The keyword engaged was 'Amaryllidaceae' in conjunction with 'inflammation' or 'anti-inflammatory', as well as the names of individual genera combined with the latter two.

RESULTS

Fifty-one species from thirty-five countries were identified for their uses against inflammation. Twenty-four of such conditions were discernible, of which their applicability in wound healing and pain management was most conspicuous. The utilization of all plant parts was apparent, preparations of which were used primarily via topical application. Extracts of seventy-three species (from twenty-three genera) were examined in nearly thirty inflammation-based assays where their activities in vitro and in vivo were shown to be significant. They were effective in vivo against pain and swelling as well as wound healing, without detriment towards test subjects. The in vitro studies were carried out mainly in mononuclear cells such as macrophages, leukocytes, lymphocytes and neutrophils against which their cytotoxic effects were seen to be minimal. The modes of operation were shown to involve modulation of both pro-inflammatory (such as NF-κB, TNF-α, IL-6, IFN-γ, COX and NO) and anti-inflammatory (such as IL-10) factors.

CONCLUSIONS

The Amaryllidaceae is showcased as a platform highly conducive towards studies in the inflammation arena. Potent activities in instances were observed via in vitro and in vivo models of study, bolstered by the significant amounts of information emerging from traditional forms of medicine. It is conceivable that the family may yield future anti-inflammatory chemotherapeutics, particularly those related to its alkaloid principles.

Carbamate as a potential anti-Alzheimer's pharmacophore: A review

Alzheimer's disease (AD) is a progressive age-related neurodegenerative brain disorder, which leads to loss of memory and other cognitive dysfunction. The underlying mechanisms of AD pathogenesis are very complex and still not fully explored. Cholinergic neuronal loss, accumulation of amyloid plaque, metal ions dyshomeostasis, tau hyperphosphorylation, oxidative stress, neuroinflammation, and mitochondrial dysfunction are major hallmarks of AD. The current treatment options for AD are acetylcholinesterase inhibitors (donepezil, rivastigmine, and galantamine) and NMDA receptor antagonists (memantine). These FDA-approved drugs mainly provide symptomatic relief without addressing the pathological aspects of disease progression. So, there is an urgent need for novel drug development that not only addresses the basic mechanisms of the disease but also shows the neuroprotective property. Various research groups across the globe are working on the development of multifunctional agents for AD amelioration using different core scaffolds for their design, and carbamate is among them. Rivastigmine was the first carbamate drug investigated for AD management. The carbamate fragment, a core scaffold of rivastigmine, act as a potential inhibitor of acetylcholinesterase. In this review, we summarize the last 10 years of research conducted on the modification of carbamate with different substituents which primarily target ChE inhibition, reduce oxidative stress, and modulate Aβ aggregation.

Tryptamine: A privileged scaffold for the management of Alzheimer's disease

Alzheimer's disease (AD) is a chronic and irreversible neurodegenerative disease associated with aging. It is characterized by the progressive loss of memory and other cognitive functions. Although the exact etiology of AD is not well explored, several factors, such as the deposition of amyloid-β (Aβ) plaques, hyperphosphorylation of tau protein, presence of low levels of acetylcholine, and generation of oxidative stress, are key mediators in the progression of AD. Currently, the clinical treatment options for AD are limited and are based on cholinesterase (ChE) inhibitors (e.g., donepezil, rivastigmine, and galantamine), N-methyl- d-aspartic acid receptor antagonists (e.g., memantine), and the recently approved Aβ modulator (e.g., aducanumab). Tryptamine (2-(1H-indol-3-yl)ethan-1-amine) is a small molecule that contains an indole nucleus and an ethylamine side chain. It is also the active metabolite of tryptophan. It possesses a wide range of biological activities related to neurodegenerative disorders, such as ChE inhibition, Aβ aggregation inhibition, antioxidant effects, monoamine-oxidase inhibition, and neuroprotection. Several tryptamine-based hybrid analogs are currently being investigated as multifunctional agents for the development of novel hybrids for AD treatment. Thus, this review article aims to provide in-depth insights into the research progress and strategies for designing multifunctional agents used in Alzheimer's therapy.

Intervertebral Disk Regeneration in a Rat Model via a Nanocomposite Collagen Hydrogel Loaded with Galanthus Extract: An In Vitro and In Vivo Study

In the current study, Galanthus extract was loaded into electrospun gelatin scaffolds using an electrospun method and then crushed. The resulting nanofibers were loaded into a collagen hydrogel to develop a filler material to treat nucleus pulposus injuries in the intervertebral disks. The nanocomposite hydrogel was studied regarding its biocompatibility, antiinflammatory activity, and swelling behavior. In Vivo study was performed in a rat model of intervertebral disk injury. Histopathological studies showed that the animals treated with the nanocomposite hydrogel restored its nucleus pulposus to a significantly higher extent than other experimental groups.

Coriandrum sativum L.: A Review on Ethnopharmacology, Phytochemistry, and Cardiovascular Benefits

Coriandrum sativum (C. sativum), belonging to the Apiaceae (Umbelliferae) family, is widely recognized for its uses in culinary and traditional medicine. C. sativum contains various phytochemicals such as polyphenols, vitamins, and many phytosterols, which account for its properties including anticancer, anti-inflammatory, antidiabetic, and analgesic effects. The cardiovascular benefits of C. sativum have not been summarized before, hence this review aims to further evaluate and discuss its effectiveness in cardiovascular diseases, according to the recent literature. An electronic search for literature was carried out using the following databases: PubMed, Scopus, Google Scholar, preprint platforms, and the Cochrane Database of Systematic Reviews. Articles were gathered from the inception of the database until August 2021. Moreover, the traditional uses and phytochemistry of coriander were surveyed in the original resources and summarized. As a result, most of the studies that cover cardiovascular benefits and fulfilled the eligibility criteria were in vivo, while only a few were in vitro and clinical studies. In conclusion, C. sativum can be deemed a functional food due to its wide range of cardiovascular benefits such as antihypertensive, anti-atherogenic, antiarrhythmic, hypolipidemic as well as cardioprotective effects.