Fourteen undescribed steroidal saponins from Solanum capsicoides leaves and their neuroprotective effects.

A total of 14 previously undescribed steroidal saponins named capsicsaponins A-N were isolated from the leaves of Solanum capsicoides, encompassing various types, including cholesterol derivatives and pseudospirostanol saponins. The structures of all compounds were determined through comprehensive analysis of spectroscopic data (1D NMR and 2D NMR), along with physicochemical analysis methods (acid hydrolysis, OR, and UV). Moreover, in the H2O2-induced pheochromocytoma cell line model, compounds 1-14 were screened for their neuroprotective effects on cells. The bioassay results demonstrated compounds 8-14 were able to revive cell viability compared to the positive control edaravone. The damage neuroprotection of the most active compound was further explored.

Bioactive neolignan, iridoid and flavonoid glycosides from the leaves of Vaccinium bracteatum.

Two neolignan glycosides including a new one (1), along with seven iridoid glycosides (3 - 9) and nine flavonoid glycosides (10 - 18), were isolated from the leaves of Vaccinium bracteatum. Their structures were established mainly on the basis of 1D/2D NMR and ESIMS analyses, as well as comparison to known compounds in the literature. The structure of 1 with absolute stereochemistry was also confirmed by chemical degradation and ECD calculation. Selective compounds showed antiradical activity against ABTS and/or DPPH. Moreover, several isolates also suppressed the production of ROS in RAW264.7 cells and exerted neuroprotective effect toward PC12 cells.

Cyclopiazonic Acid and Okaramine Analogues, Including Chlorinated Compounds, from Chrysosporium undulatum YT-1.

Eight new cyclopiazonic acid (1-8) and five new okaramine (9-13) alkaloids together with 13 known compounds were isolated from the fungus Chrysosporium undulatum YT-1. Compounds 2, 4, 5, 7, 10, 11, and 13 were chlorinated indole alkaloids. The structures of compounds 1-13 were elucidated by HRESIMS and NMR spectroscopic data. Their relative and absolute configurations were established by J-based configuration analysis, NOESY, NOEDIFF experiments, ECD spectroscopic data, and biogenetic considerations. Compound 4 inhibited the growth of Bacillus subtilis with an MIC value of 6.3 µg/mL. Compounds 9-11 exhibited strong insecticidal capacity against the third instar larvae of silkworm and cotton bollworm (LD50: ≤7.56 µg/g). At 40 µM, compound 1 showed obvious neuroprotection to the PC12 cells with 6-OHDA treatment.

Bioactivity-guided isolation of the major anthocyanin from Lycium ruthenicum Murr. fruit and its antioxidant activity and neuroprotective effects in vitro and in vivo.

Lycium ruthenicum Murr. fruit (LRF) is an edible berry known for its rich anthocyanin content. Our previous study has shown that LRF-derived anthocyanins have neuroprotective effects in rats, which may be due to their effective antioxidant activity. Therefore, this study performed online HPLC-DPPH screening as a bioactivity-guided method for the preparative separation of anthocyanins from LRF. Finally, the main fraction was isolated and identified as petunidin-3,5-O-diglucoside (Pn3G5G). Pn3G5G exhibited strong antioxidant capacity during DPPH and ABTS free radical scavenge assays. Furthermore, Pn3G5G exhibited protective effects on Nε-carboxymethyllysine (CML)-treated Neuro-2a cells by enhancing cell viability in a dose-dependent manner. CML-induced apoptosis was also reduced by Pn3G5G potentially by suppressing oxidative stress and inflammation. More importantly, Pn3G5G significantly improved cognitive impairment, neuroinflammation and neuronal apoptosis in D-galactose-induced aging mice. The result suggests the development of Pn3G5G as a healthcare product or a potent dietary supplement with antioxidant and neuroprotective effects.

Rehmannioside A improves cognitive impairment and alleviates ferroptosis via activating PI3K/AKT/Nrf2 and SLC7A11/GPX4 signaling pathway after ischemia.

ETHNOPHARMACOLOGICAL RELEVANCE: Rehmannioside A is derived from Rehmannia glutinosa Libosch, which is widely used as an important ingredient in diverse traditional Chinese medicines to treat diseases caused by "kidney deficiency" such as cerebral arteriosclerosis, aging-related stroke and dementia in China. Recent studies have proved that Rehmannia glutinosa Libosch and Rehmannioside A can improve memory capability and recover nerve damage. AIM OF THE STUDY: To investigate the effect of Rehmannioside A on cognitive impairment after ischemia in rats and SH-SY5Y cells, and further evaluate the anti-oxidative and anti-ferroptosis mechanisms. MATERIALS AND METHODS: Differentially expressed proteins (DEPs) in patients after cerebral ischemic stroke were revealed by a RayBio protein array. Cognitive impairment model was established by middle cerebral artery occlusion and reperfusion (MCAO) 14 days in rats. Rehmannioside A was administered intraperitoneally injection at dose of 80 mg/kg. The SH-SY5Y cells were exposed to H2O2 for 24 h and treated with Rehmannioside A (80 µM) for 24 h. The neuroprotecion of Rehmannioside A were evaluated by infarct volume (TTC), neurological defects (Garcia score) and learning memory (Morris water maze test) in vivo, and cell viability (CCK-8 or LDH) in vitro. Superoxide dismutase (SOD), malondialdehyde (MDA) and myeloperoxidase (MPO) activity of rats, glutathione (GSH), oxidized glutathione (GSSG) and nicotinamide adenine dinucleotide phosphate (NADPH) of cells were detected by biochemical assay. Intracellular reactive oxygen species (ROS) were measured by DCFH-DA assay. Myeloperoxidase (MPO), PI3 kinase (PI3K), p-PI3K, Akt, p-Akt, heme oxygenase-1 (HO-1), nuclear factor-E2-related factor 2 (Nrf2), SLC7A11, glutathione peroxidase 4 (GPX4) of the cerebral cortex in rats or SH-SY5Y cells were examined by western blotting. RESULTS: Compared with model group, the cognitive impairment and neurological deficits of Rehmannioside A group were significantly improved, and the cerebral infarction was reduced in MCAO rats. Moreover, the cell viability obviously increased and the H2O2-induced toxicity was reduced in Rehmannioside A group. Further research indicated that the expression of p-PI3K, p-Akt, nuclear Nrf2, HO-1 and SLC7A11 in Rehmannioside A group was significantly higher than model group. CONCLUSION: Rehmannioside A has neuroprotection effect and improves cognitive impairment after cerebral ischemia by inhibiting ferroptosis and activating PI3K/AKT/Nrf2 and SLC7A11/GPX4 signaling pathway. These findings provide valuable insight into the pathogenesis and therapeutic target of ischemic stroke.

Silybin B exerts protective effect on cisplatin-induced neurotoxicity by alleviating DNA damage and apoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Silybum marianum is a traditional Chinese medicine that has been used for treating liver disease. Silybin consisting of silybin A and silybin B, is a member of Silybum marianum, and exerts a therapeutic effect on many diseases. However, the protective effect of silybin on cisplatin-induced neurotoxicity and the stereoisomer contributing to the effect remain unknown. AIM OF THE STUDY: The present study aimed to study the effect of silybin on cisplatin-induced neuronal injury, compare the difference of protective effect between silybin A and silybin B, and the potential mechanism. MATERIALS AND METHODS: High performance liquid chromatography (HPLC) was used to separate silybin A and silybin B. X-ray crystallographic analysis in combination with experimental and calculated ECD were performed to identify the structure of silybin A and silybin B. The toxicity of the silybin or cisplatin against murine hippocampal neuronal HT22 cells was determined through MTT assay. The cell cycle and cell apoptosis were measured by PI staining and Annexin V-FITC/PI staining, respectively, and then subjected to flow cytometry. Western blot analysis was conducted to quantify the expression of proteins related to apoptosis and DNA damage. Immunofluorescence was used to evaluate the expression of DNA damage marker. In vivo experiment, the behavioral analysis was determined through pole test, swimming test and Morris water maze test. The index of superoxide dismutase (SOD), reduced glutathione (GSH), total antioxidant capacity (T-AOC) and lipid peroxidation (LPO) were examined to evaluate the antioxidant capacity in mice brain. Nissl staining and Tunel assay were used to detect the neuronal viability and apoptosis in hippocampus. RESULTS: We successfully separated and identified silybin A and silybin B. We found both silybin A and silybin B alleviated cisplatin-induced apoptosis and cell cycle arrest in HT22 cells, and silybin B was more effective. We chose silybin B for further mechanism investigation, and found silybin B alleviated DNA damage by enhancing phosphorylation of ATR and decreasing expression of γ-H2AX. In the in vivo experiment, we observed that silybin B markedly improved the behavioral abnormalities in cisplatin-treated mice, reduced LPO level while increased SOD, GSH and T-AOC in mice brain tissue. Nissl staining and Tunel assay showed that silybin B alleviated cisplatin-induced hippocampal damage. CONCLUSIONS: These results suggest that silybin B might serve as a promising drug candidate in mitigating cisplatin-induced neural injury in the brain and thereby improving the chemotherapeutic outcomes.

Panaxadiol inhibits IL-1ß secretion by suppressing zinc finger protein 91-regulated activation of non-canonical caspase-8 inflammasome and MAPKs in macrophages.

ETHNOPHARMACOLOGICAL RELEVANCE: The use of Panax ginseng C.A.Mey. in traditional Chinese medicine dates back to about 5000 years ago thanks to its several beneficial and healing properties. Panaxadiol is a triterpenoid sapogenin monomer found in the roots of Panax ginseng C.A.Mey. and has been proven to have various bio-activities such as anti-inflammatory, anti-tumour and neuroprotective effects. AIM OF THE STUDY: The present study focuses on investigating the inflammation inhibitory effect and mechanism of panaxadiol by regulating zinc finger protein 91-regulated activation of non-canonical caspase-8 inflammasome and MAPKs in macrophages. MATERIALS AND METHODS: In vitro, the underlying mechanisms by which panaxadiol inhibits ZFP91-regulated IL-1ß expression were investigated using molecular docking, western blotting, RT-PCR, ELISA, immunofluorescence, and immunoprecipitation assays. In vivo, colitis was induced by oral administration of DSS in drinking water, and peritonitis was induced by an intraperitoneal injection of alum. Recombinant adeno-associated virus (AAV serotype 9) vector was used to establish ZFP91 knockdown mouse. RESULTS: We confirmed that panaxadiol inhibited IL-1ß secretion by suppressing ZFP91 in macrophages. Further analysis revealed that panaxadiol inhibited IL-1ß secretion by suppressing ZFP91-regulated activation of non-canonical caspase-8 inflammasome. Meanwhile, panaxadiol inhibited IL-1ß secretion by suppressing ZFP91-regulated activation of MAPKs. In vivo, prominent anti-inflammatory effects of panaxadiol were demonstrated in a DSS induced acute colitis mouse model and in an alum-induced peritonitis model by suppressing ZFP91-regulated secretion of inflammatory mediators, consistent with the results of the AAV-ZFP91 knockdown in mice. CONCLUSIONS: We report for the first time that panaxadiol inhibited IL-1ß secretion by suppressing ZFP91-regulated activation of non-canonical caspase-8 inflammasome and MAPKs, providing evidence for anti-inflammation mechanism of panaxadiol treatment for inflammatory diseases.

Butylated hydroxyl-toluene, 2,4-Di-tert-butylphenol, and phytol of Chlorella sp. protect the PC12 cell line against H2O2-induced neurotoxicity.

Oxidative stress is considered the main cause of cellular damage in a number of neurodegenerative disorders. One suitable ways to prevent cell damage is the use of the exogenous antioxidant capacity of natural products, such as microalgae. In the present study, four microalgae extracts, isolated from the Persian Gulf, were screened to analyze their potential antioxidant activity and free radical scavenging using ABTS, DPPH, and FRAP methods. The methanolic extracts (D1M) of green microalgae derived from Chlorella sp. exhibited potent free radical scavenging activity. In order to characterize microalgae species, microscopic observations and analysis of the expression of 18S rRNA were performed. The antioxidant and neuroprotective effects of D1M on H2O2-induced toxicity in PC12 cells were investigated. The results demonstrated that D1M significantly decreased the release of nitric oxide (NO), formation of intracellular reactive oxygen species (ROS), and the level of malondialdehyde (MDA), whereas it enhanced the content of glutathione (GSH), and activity of heme oxygenase 1 (HO-1), NAD(P)H: quinone oxidoreductase 1 (NQO1), and catalase (CAT) in PC12 cells exposed to H2O2. The pretreatment of D1M improved cell viability as measured by the MTT assay and invert microscopy, reduced cell apoptosis as examined by flow cytometry analysis, increased mitochondrial membrane potential (MMP), and diminished caspase-3 activity. The GC/MS analysis revealed that D1M ingredients have powerful antioxidant and anti-inflammatory compounds, such as butylated hydroxytoluene (BHT), 2,4-di-tert-butyl-phenol (2,4-DTBP), and phytol. These results suggested that Chlorella sp. extracts have strong potential to be applied as neuroprotective agents, for the treatment of neurodegenerative disorders.

13-Deoxo-13-iminodutomycin, a new neuroprotective compound from Streptomyces sp. RAP78.

A neuroprotective compound (2) was isolated from the culture broth of the dutomycin (1) producer Streptomyces sp. RAP78. The molecular formula of 2 was established as C44H55NO16 by high-resolution FAB-MS. The structure was determined to be a new dutomycin derivative possessing an acetimidoyl group in place of an acetyl group by NMR spectroscopic analysis. 13-Deoxo-13-iminodutomycin (2) but not dutomycin (1) protected C6 rat glioma cells and N18-RE-105 rat primary retina-mouse neuroblastoma hybrid cells from glutamate-induced toxicity with EC50s of 0.12 µM and 0.72 µM, respectively.

seco-Prezizanne Sesquiterpenes and Prenylated C6-C3 Compounds from the Fruits of Illicium lanceolatum A. C. Smith.

Two new seco-prezizaane-type sesquiterpenes, 2ß-hydroxy-6-deoxyneoanisatin (1) and 3,4-anhydro-2-oxo-1α-hydroxy-6-deoxyneoanisatin (2), and two new prenylated C6 -C3 compounds, illilanceofunones A (3) and B (4), were obtained from the fruits of Illicium lanceolatum, along with four known prenylated C6 -C3 compounds (5-8). Their structures were proposed through HR-ESI-MS, 1 H, 13 C, and 2D NMR data interpretation. Moreover, the absolute configuration of 1 and 2 were further assigned by single-crystal X-ray diffraction analysis and electronic circular dichroism (ECD) calculations, respectively. Illihenryipyranol A (6) exhibited neuroprotective activity against MPP+ -induced PC12 cell damage in a dose-dependent manner.

Neuroprotective Effects of B-Type Cinnamon Procyanidin Oligomers on MPP+-Induced Apoptosis in a Cell Culture Model of Parkinson's Disease.

Cinnamon procyanidin oligomers (CPOs) are water-soluble components extracted from cinnamon. This study aims to explore the neuroprotection of B-type CPO (CPO-B) against 1-methyl-4-phenylpyridinium (MPP+)-mediated cytotoxicity and the molecular mechanisms underlying its protection. The results demonstrated that CPO-B showed protection by increasing cell viability, attenuating an intracellular level of reactive oxygen species, downregulating cleaved caspase-3 expression, and upregulating the Bcl-2/Bax ratio. Moreover, CPO-B completely blocked the dephosphorylation of extracellular, signal-regulated kinase 1 and 2 (Erk1/2) caused by MPP+. Treatment with an Erk1/2 inhibitor, SCH772984, significantly abolished the neuroprotection of CPO-B against MPP+. Taken together, we demonstrate that CPO-B from cinnamon bark provided protection against MPP+ in cultured SH-SY5Y cells, and the potential mechanisms may be attributed to its ability to modulate the dysregulation between pro-apoptotic and anti-apoptotic proteins through the Erk1/2 signaling pathway. Our findings suggest that the addition of cinnamon to food or supplements might benefit patients with PD.

Withania somnifera (L.) Dunal (Ashwagandha): A comprehensive review on ethnopharmacology, pharmacotherapeutics, biomedicinal and toxicological aspects.

Withania somnifera (L.) Dunal (Solanaceae) has been used as a traditional Rasayana herb for a long time. Traditional uses of this plant indicate its ameliorative properties against a plethora of human medical conditions, viz. hypertension, stress, diabetes, asthma, cancer etc. This review presents a comprehensive summary of the geographical distribution, traditional use, phytochemistry, and pharmacological activities of W. somnifera and its active constituents. In addition, it presents a detailed account of its presence as an active constituent in many commercial preparations with curative properties and health benefits. Clinical studies and toxicological considerations of its extracts and constituents are also elucidated. Comparative analysis of relevant in-vitro, in-vivo, and clinical investigations indicated potent bioactivity of W. somnifera extracts and phytochemicals as anti-cancer, anti-inflammatory, apoptotic, immunomodulatory, antimicrobial, anti-diabetic, hepatoprotective, hypoglycaemic, hypolipidemic, cardio-protective and spermatogenic agents. W. somnifera was found to be especially active against many neurological and psychological conditions like Parkinson's disease, Alzheimer's disease, Huntington's disease, ischemic stroke, sleep deprivation, amyotrophic lateral sclerosis, attention deficit hyperactivity disorder, bipolar disorder, anxiety, depression, schizophrenia and obsessive-compulsive disorder. The probable mechanism of action that imparts the pharmacological potential has also been explored. However, in-depth studies are needed on the clinical use of W. somnifera against human diseases. Besides, detailed toxicological analysis is also to be performed for its safe and efficacious use in preclinical and clinical studies and as a health-promoting herb.

Neuroprotective activity of natural products isolated from Senecio graciliflorus DC against corticosterone-induced impairment in SH-SY5Y cells.

Senecio graciliflorus DC root extract was studied for secondary metabolite composition following the bioactivity-guided isolation technique. The ethyl acetate extract of Senecio graciliflorus root yielded nine chemical constituents: 3,4-di-tert-butyl toluene, stigmasterol, ß-sitosterol, 2ß-(angeloyloxy)furanoeremophilane, gallic acid, 2ß-{[(Z)-2-hydroxymethylbut-2-enoyl]oxy}furanoeremophilane, 1-hydroxypentan-2-yl-4-methylbenzoate, sarcinic acid, and sitosterol 3-O-ß-D-glucopyranoside. The structures of the chemical constituents were elucidated on the basis of spectral data analysis in the light of literature. All the compounds are being reported for the first time from this plant. The isolated constituents were screened for neuroprotective effects against corticosterone-induced impairment in neuroblastoma cell lines (SH-SY5S cells). The viability of SH-SY5S cells was determined using MTT assay. Among various isolated compounds, three natural products (sarcinic acid, gallic acid, and ß-sitosterol) displayed robust neurotropic activity. The compounds increased neuronal cell survival in differentiated neuroblastoma cells (SH-SY5Y) from high-dose corticosterone (400 µM)-induced cell death. All the three constituents showed maximum AKT/ERK pathway activation at 20 µM concentration. The studies are aimed to explore small molecules for treating neurodegeneration underlying various neurological disorders to restore neuronal cell plasticity.

Ergosta-7,9(11),22-trien-3ß-ol Rescues AD Deficits by Modulating Microglia Activation but Not Oxidative Stress.

Ergosta-7,9(11),22-trien-3ß-ol (EK100) was isolated from the Taiwan-specific medicinal fungus Antrodia camphorata, which is known for its health-promotion and anti-aging effects in folk medicine. Alzheimer's disease (AD) is a major aging-associated disease. We investigated the efficacy and potential mechanism of ergosta-7,9(11),22-trien-3ß-ol for AD symptoms. Drosophila with the pan-neuronal overexpression of human amyloid-ß (Aß) was used as the AD model. We compared the life span, motor function, learning, memory, oxidative stress, and biomarkers of microglia activation and inflammation of the ergosta-7,9(11),22-trien-3ß-ol-treated group to those of the untreated control. Ergosta-7,9(11),22-trien-3ß-ol treatment effectively improved the life span, motor function, learning, and memory of the AD model compared to the untreated control. Biomarkers of microglia activation and inflammation were reduced, while the ubiquitous lipid peroxidation, catalase activity, and superoxide dismutase activity remained unchanged. In conclusion, ergosta-7,9(11),22-trien-3ß-ol rescues AD deficits by modulating microglia activation but not oxidative stress.

A nanophytosomes formulation based on elderberry anthocyanins and Codium lipids to mitigate mitochondrial dysfunctions.

The development of nanomedicines to modulate the mitochondrial function is a great scientific challenge since mitochondrial dysfunction is a pathological hallmark of many chronic diseases, including degenerative brain pathologies like Parkinson's and Alzheimer's diseases. To address this challenge, the mitochondriotropic features of the elderberry anthocyanin-enriched extract (Sambucus nigra) were combined with the self-assembling properties of the membrane polar lipids from Codium tomentosum in an innovative SC-Nanophytosomes formulation. Membrane polar lipids, obtained by a new procedure as chlorophyll-free extract, are characterized by 26% of non-phosphorus polar lipids and 74% of phospholipids (dominated by anionic lipids) containing a high degree of polyunsaturated fatty acids. The anthocyanin-enriched extract is dominated by a mixture of four cyanidin-glycosides, representing about 86% of their phenolic content. SC-Nanophytosomes engineered with 600 µM algae membrane polar lipids and 0.5 mg/L of the anthocyanin-enriched extract are nanosized vesicles (diameter =108.74 ± 24.74 nm) with a negative surface charge (Zeta potential = -46.93 ± 6.63 mV) that exhibit stability during storage at 4 ºC. In vitro assays with SH-SY5Y cells showed that SC-Nanophytosomes have the competence to target mitochondria, improving the mitochondrial respiratory chain complexes I and II and preserving the mitochondrial membrane potential in the presence of rotenone. Additionally, SC-Nanophytosomes protect SH-SY5Y cells against the toxicity induced by rotenone or glutamate. Green-fluorescent labeled SC-Nanophytosomes were used to reveal that they are mainly internalized by cells via caveola-mediated endocytosis, escape from endosome and reach the cytoplasm organelles, including mitochondria. Overall, data indicate that SC-Nanophytosomes have the potential to support a mitochondria-targeted therapy for neurodegenerative diseases.

Bidentatide, a Novel Plant Peptide Derived from Achyranthes bidentata Blume: Isolation, Characterization, and Neuroprotection through Inhibition of NR2B-Containing NMDA Receptors.

Increasing attention is being focused on the use of polypeptide-based N-methyl-d-aspartate (NMDA) receptor antagonists for the treatment of nervous system disorders. In our study on Achyranthes bidentata Blume, we identified an NMDA receptor subtype 2B (NR2B) antagonist that exerts distinct neuroprotective actions. This antagonist is a 33 amino acid peptide, named bidentatide, which contains three disulfide bridges that form a cysteine knot motif. We determined the neuroactive potential of bidentatide by evaluating its in vitro effects against NMDA-mediated excitotoxicity. The results showed that pretreating primary cultured hippocampal neurons with bidentatide prevented NMDA-induced cell death and apoptosis via multiple mechanisms that involved intracellular Ca2+ inhibition, NMDA current inhibition, and apoptosis-related protein expression regulation. These mechanisms were all dependent on bidentatide-induced inhibitory regulation of NR2B-containing NMDA receptors; thus, bidentatide may contribute to the development of neuroprotective agents that would likely possess the high selectivity and safety profiles inherent in peptide drugs.

Different types of components obtained from Monascus purpureus with neuroprotective and anti-inflammatory potentials.

The mold Monascus has been used as a natural food coloring agent and food additive for more than 1000 years in Asian countries. In Chinese herbology, it was also used for easing digestion and antiseptic effects. Through a thorough investigation of a citrinin-free strain: M. purpureus BCRC 38110, four azaphilones, three benzenoids, one benzofuranone, one 5',6'-dihydrospiro[isochromane-1,2'-pyran]-4'(3'H)-one derivative, two steroids, and six tetralones have been successfully identified. Among them, monapyridine A (1), monatetralones A-E (2-6), and monabenzofuranone (7) were first reported. Their structures were characterized by 1D and 2D NMR, UV, IR, and HRESIMS analyses. With a series of bioactivity screening, monascuspirolide B (14) and ergosterol peroxide (16) exhibited concentration-dependent attenuation of the paclitaxel-induced neurite damage of mouse dorsal root ganglion neurons. The interleukin (IL)-1ß-induced release of inflammatory cytokines IL-8 and tumor necrosis factor (TNF)-α in human chondrosarcoma cells was inhibited by monapurpureusone (8) and monascuspirolide B (14). Altogether, M. purpureus BCRC 38110 possessed potentials as natural therapeutics against inflammatory osteoarthritis and paclitaxel-induced neurotoxicity.

Polycyclic polyprenylated acylphloroglucinols with immunosuppressive activity from Hypericum perforatum and absolute configurations assignment of previously reported analogues.

Hyperformitins A-I (1-9), nine undescribed polycyclic polyprenylated acylphloroglucinols (PPAPs) with double-bond migration, along with four new isomers hyperformitins J-M (10-13), were isolated from Hypericum perforatum. Their structures and absolute configurations were determined by spectroscopic analyses including HRESIMS, IR, UV, NMR, and ECD, as well as optical rotation (OR) calculations. The absolute configurations of previously reported analogues, garsubellins D and C as well as garcinielliptones L and M, were assigned for the first time by NMR spectra and specific rotations analyses assisting with OR calculations. Selected compounds were tested for their immunosuppressive activities against lipopolysaccharide (LPS)-induced B lymphocyte proliferation. Compounds 1, 3, 4, 5, 7, and 11 showed inhibition activities against the proliferation of B lymphocyte with IC50 values ranging from 4.1 to 9.7 µM. Furthermore, the neuroprotective activities of the isolates against corticosterone (CORT)-induced injury in PC12 cells were also tested, and compounds 1, 12, and 13 exhibited neuroprotective effects with cell viabilities of 68.0%, 71.3%, and 68.4%, respectively under the concentration of 10 µM.

Bridging Cyanobacteria to Neurodegenerative Diseases: A New Potential Source of Bioactive Compounds against Alzheimer's Disease.

Neurodegenerative diseases (NDs) represent a drawback in society given the ageing population. Dementias are the most prevalent NDs, with Alzheimer's disease (AD) representing around 70% of all cases. The current pharmaceuticals for AD are symptomatic and with no effects on the progression of the disease. Thus, research on molecules with therapeutic relevance has become a major focus for the scientific community. Cyanobacteria are a group of photosynthetic prokaryotes rich in biomolecules with confirmed activity in pathologies such as cancer, and with feasible potential in NDs such as AD. In this review, we aimed to compile the research works focused in the anti-AD potential of cyanobacteria, namely regarding the inhibition of the enzyme ß-secretase (BACE1) as a fundamental enzyme in the generation of ß-amyloid (Aß), the inhibition of the enzyme acetylcholinesterase (AChE) lead to an increase in the availability of the neurotransmitter acetylcholine in the synaptic cleft and the antioxidant and anti-inflammatory effects, as phenomena associated with neurodegeneration mechanisms.

Neuroprotective Activities of Crossyne flava Bulbs and Amaryllidaceae Alkaloids: Implications for Parkinson's Disease.

Parkinson's disease (PD) is one of the most common neurodegenerative diseases and affects approximately 6.3 million people worldwide. To date, the treatment of PD remains a challenge, as available treatment options are known to be associated with serious side effects; hence, the search for new treatment strategies is critical. Extracts from the Amaryllidaceae plant family as well as their alkaloids have been reported to have neuroprotective potentials. This study, therefore, investigated the biological activities of Crossyne flava and its isolated alkaloids in an in vitro MPP+ (1-methyl-4-phenylpyridinium) PD model using SH-SY5Y cells. The effects of the total extract as well as the four compounds isolated from Crossyne flava (i.e., pancratinine B (1), bufanidrine (2), buphanisine (3), and epibuphanisine (4)) were evaluated for cell viability, neuroprotection, levels of reactive oxygen species (ROS), adenosine triphosphate activity (ATP), and caspase 3/7 activity in SH-SY5Y cells. The results obtained showed that pre-treatment with both the extract and the isolated compounds was effective in protecting the SH-SY5Y cells from MPP+-induced neurotoxicity and inhibited ROS generation, ATP depletion as well as apoptosis induction in the SH-SY5Y cells. The results of this study show that the Amaryllidaceae plant family may be a source of novel compounds for the treatment of neurodegenerative diseases, which validates the reported traditional uses.