Pandanus amaryllifolius Exhibits In Vitro Anti-Amyloidogenic Activity and Promotes Neuroprotective Effects in Amyloid-ß-Induced SH-SY5Y Cells.

Accumulation of amyloid-beta (Aß) plaques leading to oxidative stress, mitochondrial damage, and cell death is one of the most accepted pathological hallmarks of Alzheimer's disease (AD). Pandanus amaryllifolius, commonly recognized as fragrant screw pine due to its characteristic smell, is widely distributed in Southeast Asia and is consumed as a food flavor. In search for potential anti-AD agents from terrestrial sources, P. amaryllifolius was explored for its in vitro anti-amyloidogenic and neuroprotective effects. Thioflavin T (ThT) assay and the high-throughput screening multimer detection system (MDS-HTS) assay were used to evaluate the extracts' potential to inhibit Aß aggregations and oligomerizations, respectively. The crude alcoholic extract (CAE, 50 µg/mL) and crude base extract (CBE, 50 µg/mL) obstructed the Aß aggregation. Interestingly, results revealed that only CBE inhibited the Aß nucleation at 100 µg/mL. Both CAE and CBE also restored the cell viability, reduced the level of reactive oxygen species, and reversed the mitochondrial dysfunctions at 10 and 20 µg/mL extract concentrations in Aß-insulted SY-SY5Y cells. In addition, the unprecedented isolation of nicotinamide from P. amaryllifolius CBE is a remarkable discovery as one of its potential bioactive constituents against AD. Hence, our results provided new insights into the promising potential of P. amaryllifolius extracts against AD and further exploration of other prospective bioactive constituents.

Multi-Target Approach of Murraya koenigii Leaves in Treating Neurodegenerative Diseases.

Neurodegenerative diseases (NDs) mainly affect neurons and gradually lead to a loss of normal motor and cognitive functions. Atypical protein homeostasis-misfolding, aggregations and accumulations, oxidative stress, inflammation, and apoptosis-are common features in most NDs. To date, due to the complex etiology and pathogenesis of NDs, no defined treatment is available. There has been increasing interest in plant extracts as potential alternative medicines as the presence of various active components may exert synergistic and multi-pharmacological effects. Murraya koenigii (Rutaceae) is utilized in Ayurvedic medicine for various ailments. Pharmacological studies evidenced its potential antioxidant, anti-inflammatory, anticancer, hepatoprotective, immunomodulatory, antimicrobial, and neuroprotective activities, among others. In line with our interest in exploring natural agents for the treatment of neurodegenerative diseases, this review presents an overview of literature concerning the mechanisms of action and the safety profile of significant bioactive components present in M. koenigii leaves to support further investigations into their neuroprotective therapeutic potential.

Phytosterols: Potential Metabolic Modulators in Neurodegenerative Diseases.

Phytosterols constitute a class of natural products that are an important component of diet and have vast applications in foods, cosmetics, and herbal medicines. With many and diverse isolated structures in nature, they exhibit a broad range of biological and pharmacological activities. Among over 200 types of phytosterols, stigmasterol and ß-sitosterol were ubiquitous in many plant species, exhibiting important aspects of activities related to neurodegenerative diseases. Hence, this mini-review presented an overview of the reported studies on selected phytosterols related to neurodegenerative diseases. It covered the major phytosterols based on biosynthetic considerations, including other phytosterols with significant in vitro and in vivo biological activities.

Mechanistic Aspects of Apiaceae Family Spices in Ameliorating Alzheimer's Disease.

Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases worldwide. In an effort to search for new strategies for treating AD, natural products have become candidates of choice. Plants are a rich source of bioactive and effective compounds used in treating numerous diseases. Various plant extracts are known to display neuroprotective activities by targeting different pathophysiological pathways in association with the diseases, such as inhibiting enzymes responsible for degrading neurotransmitters, reducing oxidative stress, neuroprotection, inhibiting amyloid plaque formation, and replenishing mitochondrial function. This review presented a comprehensive evaluation of the available scientific literature (in vivo, in vitro, and in silico) on the neuroprotective mechanisms displayed by the extracts/bioactive compounds from spices belonging to the Apiaceae family in ameliorating AD.

Anti-Amyloidogenic and Cyclooxygenase Inhibitory Activity of Guettarda speciosa.

Guettarda speciosa is known in traditional folk medicine for treating cough, cold, sore throat, fever, wounds, epilepsy, and headaches. To discover the scientific pharmacological potential of G. speciosa, we explore its anti-inflammatory, cytotoxicity, and inhibition of amyloid-beta (Aß) aggregation effects. Cyclooxygenase assay of the G. speciosa CHCl3 (GSC) extract and G. speciosa MeOH (GSM) extract are more selective to COX-1 inhibition with a 50% inhibitory concentration (IC50) of 3.56 µg/mL for the GSC extract and 4.98 µg/mL for the GSM extract. Neuroblastoma SH-SY5Y inhibition and thioflavin T assay amyloid-beta (Aß) aggregate inhibition of the GSM and GSC extracts showed their potential therapeutic effects against Alzheimer's disease. The putative compounds from the LC-MS analysis could be responsible for the observed activities. The results suggest that G. speciosa possesses anti-inflammatory and anti-neurodegenerative properties and a promising lead as a source of pharmacologically active compounds.

Recent Progress in the Chemistry of Pandanus Alkaloids.

The genus Pandanus (Pandanaceae) is widely distributed in the tropical and subtropical regions. With about 700 species worldwide, three Pandanus species (P. amaryllifolius, P. utilis, and P. dubius) have been investigated and found to contain new alkaloids possessing a pyrrolidinyl-α,ß-unsaturated γ-lactone, a γ-butylidene-α-methyl-α,ß-unsaturated γ-lactam, and/or indolizidine residues. Several total syntheses of Pandanus alkaloids have been accomplished. Several pharmacological studies on Pandanus species, including scientific validations of their antibacterial, antiinflammatory, antidiarrheal, and cytotoxic activities, have been conducted in relation to their traditional folk medicine uses.

Lipid-lowering property of Clausena anisum-olens in hypercholesterolemic rats.

CONTEXT: Clausena anisum-olens (Blanco) Merr. (Rutaceae) is a medicinal shrub which has been reported to have various pharmacological uses. No study regarding the effects of C. anisum-olens on cholesterol-lowering has been reported. OBJECTIVE: The effects of the ethanol extract of C. anisum-olens leaves on the cholesterol level of hypercholesterolemic rats were evaluated. MATERIALS AND METHODS: Acute oral toxicity of the extract (175, 550 and 2000 mg/kg) was determined using female Sprague-Dawley rats, as described in OECD 425 Main test guidelines. The lipid-lowering assay utilized 30 male Sprague-Dawley rats divided into five groups (A-E). Triton X-100 was administered to induce hypercholesterolemia. After hypercholesterolemia induction, oral treatment of Atorvastatin and crude ethanol extract was given daily to the treatment groups for 14 days. The total cholesterol, triglycerides, HDL and LDL were determined before induction, after induction, after first week of treatment and after second week of treatment. RESULTS: Acute oral toxicity showed the crude extract is nontoxic up to 2000 mg/kg. The lipid-lowering assay indicated reduction of serum cholesterol (87.21 ± 5.10 mg/dL), triglycerides (58.09 ± 4.10 mg/dL) and LDL (27.82 ± 4.11 mg/dL) for 200 mg/kw extract. Reduction in serum cholesterol (74.72 ± 3.64 mg/dL), triglycerides (52.79 ± 2.98 mg/dL) and LDL (12.06 ± 5.51 mg/dL) were observed for 400 mg/kg group. The result is comparable to Atorvastatin, which showed serum cholesterol (80.90 ± 9.72 mg/dL), triglycerides (55.94 ± 7.19 mg/dL) and LDL (22.09 ± 7.60 mg/dL) reduction. DISCUSSION AND CONCLUSION: The crude extract of C. anisum-olens proved to be useful in lowering of cholesterol.

Iridoids and a norsesquiterpenoid from the leaves of Villaria odorata.

Phytochemical investigation of Villaria odorata, a Philippine endemic Rubiaceae species, led to the identification of three iridoids, morindolide (1), hydrophylin A (2), hydrophylin B (3) and a norsesquiterpenoid, vomifoliol (4). This is the first report of compounds 1-4 from the genus Villaria. These classes of compounds proved to be important chemotaxonomic markers in the Rubiaceae family in combination with morphology and molecular data.

Bioactive metabolites of Diaporthe sp. P133, an endophytic fungus isolated from Pandanus amaryllifolius.

Two new benzopyranones, diaportheone A (1) and B (2), were obtained via bioassay-guided isolation of the secondary metabolites from the endophytic fungus Diaporthe sp. P133 isolated from Pandanus amaryllifolius leaves. Their structures were determined from spectral analysis including mass spectrometry, 1D and 2D nuclear magnetic resonance. Both 1 and 2 inhibited the growth of the virulent strain of Mycobacterium tuberculosis H(37)Rv with minimum inhibitory concentrations of 100.9 and 3.5 µM, respectively.

Antitubercular triterpenes and phytosterols from Pandanus tectorius Soland. var. laevis.

Bioassay-guided chromatographic purification of the antitubercular chloroform extract of Pandanus tectorius Soland. var. laevis leaves afforded a new tirucallane-type triterpene, 24,24-dimethyl-5 beta-tirucall-9(11),25-dien-3-one (1), squalene and a mixture of the phytosterols stigmasterol and beta-sitosterol. Microplate Alamar Blue Assay (MABA) showed that 1 inhibited the growth of Mycobacterium tuberculosis H(37)Rv with a MIC of 64 microg/mL, while squalene and the sterol mixture have MICs of 100 and 128 microg/mL, respectively.