Lupeol and Its Role in Chronic Diseases.

Lupeol belongs to pentacyclic lupane-type triterpenes and exhibits in edible vegetables, fruits and many plants. Many researches indicated that lupeol possesses many beneficial pharmacological activities including antioxidant, anti-inflammatory, anti-hyperglycemic, anti-dyslipidemic and anti-mutagenic effects. From various disease-targeted animal models, these reports indicated that lupeol has anti-diabetic, anti-asthma, anti-arthritic, cardioprotective, hepatoprotective, nephroprotective, neuroprotective and anticancer efficiency under various routes of administration such as topical, oral, subcutaneous, intraperitoneal and intravenous. It is worth mentioning that clinical trials of lupeol were performed to treat canine oral malignant melanoma and human moderate skin acne in Japan and Korea. The detailed mechanism of anti-inflammatory, anti-diabetic, hepatoprotective and anticancer activities was further reviewed from published papers. These evidence indicate that lupeol is a multi-target agent to exert diverse pharmacological potency with many potential targeting proteins such as α-glucosidase, α-amylase, protein tyrosine phosphatase 1B (PTP 1B) and TCA cycle enzymes and targeting pathway such as IL-1 receptor-associated kinase-mediated toll-like receptor 4 (IRAK-TLR4), Bcl-2 family, nuclear factor kappa B (NF-kB), phosphatidylinositol-3-kinase (PI3-K)/Akt and Wnt/ß-catenin signaling pathways. This review also provides suggestion that lupeol might be a valuable and potential lead compound to develop as anti-inflammatory, anti-diabetic, hepatoprotective and anticancer drugs.

Predictive Analysis of Yi-Gai-San's Multifaceted Mechanisms for Tremor-dominant Parkinson's Disease via Network Pharmacology and Molecular Docking Validation.

INTRODUCTION: Based on comprehensive network-pharmacology and molecular docking analysis, this study was intended to unveil the multiple mechanisms of Yi- Gai-San (YGS) in treating the tremor-dominant subtype of Parkinson's disease (PD-DT). The compounds of YGS were meticulously analyzed, selected, and standardized with references to their pharmacological attributes. Its components included Gouteng (Uncaria rhynchophylla), Chaihu (Radix Bupleuri), Chuanxiong (Chuanxiong Rhizoma), Danggui (Angelicae sinensis radix), Fuling (Wolfiporia extensa), Baizhu (Atractylodis macrocephalae rhizoma), and Gancao (Licorice, Glycyrrhizae radix). METHODS: We identified 75 active compounds within YGS. From these, we predicted 110 gene targets, which exhibited a direct association with PD-DT. PPI network results highlighted core target proteins, including TP53, SLC6A3, GAPDH, MAOB, AKT, BAX, IL6, BCL2, PKA, and CASP3. These proteins potentially alleviate PD-DT by targeting inflammation, modulating neuronal cell apoptosis, and regulating the dopamine system. Furthermore, GO and KEGG enrichment analyses emphasized that YGS might influence various mechanisms, such as the apoptotic process, mitochondrial autophagy, Age-Rage signaling, and dopaminergic and serotonergic synapses. The core proteins from the PPI analysis were selected for the docking experiment. RESULTS: The docking results demonstrated that the most stable ligand-receptor conformations were kaempferol with CASP3 (-9.5 kcal/mol), stigmasterol with SLC6A3 (-10.5 kcal/mol), shinpterocarpin with BCL2L1 (-9.6 kcal/mol), hirsutine with MAOB (-9.7 kcal/mol), hederagenin with PRKACA (-9.8 kcal/mol), and yatein with GAPDH (-9.8 kcal/mol). These results provide us with research objectives for future endeavors in extracting single compounds for drug manufacturing or in-depth studies on drug mechanisms. CONCLUSION: From these computational findings, we suggested that YGS might mitigate PD-DT via "multi-compounds, multi-targets, and multi-pathways."

Schizandrin protects primary rat cortical cell cultures from glutamate-induced apoptosis by inhibiting activation of the MAPK family and the mitochondria dependent pathway.

Glutamate-induced excitotoxicity has been implicated in a variety of neuronal degenerative disorders. In the present study, we investigated the possible neuroprotective effects of schizandrin against apoptosis of primary cultured rat cortical cells induced by glutamate. Glutamate (10 µM) administered for 24 h decreased the expression of Bcl-2 and Bcl-X(L) protein, whereas increased the expression of Bax, Bak, apoptosis inducing factor (AIF), endonuclease G (Nodo G) and endoplasmic reticulum (ER) stress of caspase-12. Pretreatment with schizandrin (100 µM) before glutamate treatment increased the Bcl-X(L) and Bcl-2 expression and decreased Bax, Bak, AIF, Nodo G and caspase-12 compared with those only treated with glutamate. Furthermore, glutamate-induced phosphorylation of JNK, p38 and ERK mitogen-activated protein kinases (MAPK), and these effects were attenuated by schizandrin (100 µM) treatment. These results suggest that schizandrin possesses the neuroprotective effects. The molecular mechanisms of schizandrin against glutamate-induced apoptosis may involve the regulation of Bcl-2 family proteins expression, and ER stress through blocking the activation of JNK, ERK and p38 MAPK.

Neuroprotective effect of luteolin on amyloid beta protein (25-35)-induced toxicity in cultured rat cortical neurons.

The present study was carried out to investigate the neuroprotective effect of luteolin on amyloid beta (Abeta) (25-35)-induced neurotoxicity using cultured rat cortical neurons. After exposure of primary cultures of rat cortical cells to 10 muM Abeta (25-35) for 48 h, cortical cell cultures exhibited marked apoptotic death. Pretreatment with luteolin (1, 10 microM) significantly protected cortical cell cultures against Abeta (25-35)-induced toxicity. Luteolin (1, 10 microM) showed a concentration-dependent inhibition on 10 muM Abeta (25-35)-induced apoptotic neuronal death, as assessed by MTT assay. Furthermore, luteolin reduced apoptotic characteristics by DAPI staining. For Western blot analysis, the results showed that the protective effect of luteolin on Abeta (25-35)-induced neurotoxicity was mediated by preventing of ERK-p, JNK, JNK-p, P38-p and caspase 3 activations in rat primary cortical cultures. Taken together, the results suggest that luteolin prevents Abeta (25-35)-induced apoptotic neuronal death through inhibiting the protein level of JNK, ERK and p38 MAP kinases and caspase 3 activations.

Differential change in cortical and hippocampal monoamines, and behavioral patterns in streptozotocin-induced type 1 diabetic rats.

OBJECTIVES: Diabetes mellitus (DM) is a widespread metabolic disorder worldwide. Clinical physicians have found diabetic patients have mild to middle cognitive dysfunction and an alteration of brain monoaminergic function. This study explored the change in various patterns of behavioral models and brain monoamine function under streptozotocin (STZ)-induced type 1 diabetes. MATERIALS AND METHODS: We established a type 1 DM model via intravenous injection with STZ (65 mg/kg) in rats. Three weeks after the STZ injection, various behavioral measurements including the inhibitory avoidance test, active avoidance test and Morris water maze were conducted. Finally, all rats were dissected and the concentrations of monoamines and their metabolites in cortex and hippocampus were measured by high performance liquid chromatography with electrochemical detection. RESULTS: We found that STZ induced type 1 diabetes (hyperglycemia and lack of insulin) in rats. STZ-induced diabetic rats had cognitive impairment in acquisition sessions and long-term retention of the active avoidance test. STZ-induced diabetic rats also had cognitive impairment in spatial learning, reference and working memory of the Morris water maze. STZ significantly reduced concentrations of norepinephrine (NE) in the cortex and dopamine (DA) in the hippocampus, but increased concentrations of DA and serotonin (5-HT) in the cortex 35 days after injection. The concentration of 5-HT in the hippocampus was also significantly increased. CONCLUSION: The data suggested that this cognitive impairment after a short-term period of STZ injection might be related to cortical NE dysfunction, differential alteration of cortical and hippocampal DA function, and brain 5-HT hyperfunction.

Effects of luteolin on learning acquisition in rats: involvement of the central cholinergic system.

The study was conducted to investigate the ameliorating effects of luteolin on memory acquisition in rats. The effects of luteolin on scopolamine-induced impairment of passive avoidance response were evaluated primarily, as well as the role of the central nervous system through the use of central neurotoxins and central nervous antagonists. Luteolin was not reversed by scopolamine N-methylbromide (M-SCOP) but blocked the impairment of learning acquisition induced by cholinergic neurotoxin (ethylcholine aziridinium, AF64A) and muscarinic (scopolamine hydrobromide, SCOP) and nicotinic (mecamylamine, MECA) receptor antagonists. However, it did not block dopaminergic neurotoxin (6-hydroxydopamine, 6-OHDA)-induced and serotonergic neurotoxin (5,7-dihydroxytryptamine, 5,7-DHT)-induced impairments. From these results, we suggest that the attenuating effect of luteolin (10 mg/kg, i.p.) on the deficits of passive avoidance performance induced by SCOP may be related to the increases in the activities of central muscarinic and nicotinic receptors.

p-Hydroxybenzyl Alcohol, an Active Phenolic Ingredient of Gastrodia elata, Reverses the Cycloheximide-Induced Memory Deficit by Activating the Adrenal Gland in Rats.

The present study investigated the ameliorating effects of p-hydroxybenzyl alcohol (HBA), an active phenolic ingredient of Gastrodia elata, on cycloheximide (CXM)-induced impairment of passive avoidance response and clarified the role of adrenal glands on the effect of HBA in rats. An adrenalectomy (ADX) caused the memory deficit from 1 to 3 days after surgery. Administration of corticosterone (CORT) plus glucose completely recovered the memory deficit caused by ADX, and this effect was better than that of glucose or CORT alone. HBA ameliorated the memory deficit induced by CXM in sham and ADX rats, but ADX partially blocked it. Furthermore, plasma glucose, epinephrine and adrenal steroid levels of ADX rats significantly decreased. Sham rats who received HBA had an increase in plasma glucose and adrenal steroid levels. Therefore, we suggest that the reversal of CXM-induced memory deficit by HBA was partially dependent on adrenal glands through the increase of the levels of plasma adrenal steroids.

Ferulic acid reverses the cognitive dysfunction caused by amyloid ß peptide 1-40 through anti-oxidant activity and cholinergic activation in rats.

Cholinergic dysfunction and oxidation stress are the dominant mechanisms of memory deficit in Alzheimer's disease (AD). This study describes how ferulic acid (FA) ameliorates cognitive deficits induced by mecamylamine (MECA), scopolamine (SCOP), central acetylcholinergic neurotoxin ethylcholine mustard aziridinium ion (AF64A) and amyloid ß peptide (Aß1-40). This study also elucidates the role of anti-oxidant enzymes and cholinergic marker acetylcholinesterase (AChE) in the reversal of FA from Aß1-40-induced cognitive deficits in rats. At 100 mg/kg, FA attenuated impairment induced by MECA and SCOP plus MECA; however, this improvement was not blocked by the peripheral muscarinic receptor antagonist scopolamine methylbromide (M-SCOP). At 100 and 300 mg/kg, FA also attenuated the impairment of inhibitory passive avoidance induced by AF64A. Further, FA attenuated the performance impairment and memory deficit induced by Aß1-40 in rats, as did vitamin E/C. FA reversed the deterioration of superoxide dismutase (SOD) and AChE activities, and the glutathione disulfide (GSSG) and glutathione (GSH) levels in the cortex and hippocampus. Vitamin E/C only selectively reversed deterioration in the hippocampus. We suggest that FA reduced the progression of cognitive deficits by activating central muscarinic and nicotinic receptors and anti-oxidant enzymes.

The ameliorating effects of luteolin on beta-amyloid-induced impairment of water maze performance and passive avoidance in rats.

The present study investigated the effects of luteolin on Abeta (1-40)-induced impairment of Morris water maze (MWM) spatial performance, reference memory, and passive avoidance (PA) behavior in rats. Luteolin treatment was started 4 days before the initiation of behavioral testing (passive avoidance on treatment day of 4-5; MWM spatial performance memory testing on treatment day of 5-7 and MWM reference memory testing on treatment day of 7) and continued until the end of the study. We also measured the activity of Mn-SOD, copper/zinc (Cu/Zn)-SOD and glutathione (GSH) levels in rat cortex and hippocampus to understand the ameliorating effect of luteolin on Abeta (1-40) induced memory impairment. The present results showed that luteolin (5, 10 mg/kg) has a protective effect on Abeta (1-40)-induced memory dysfunction in spatial performance, reference memory, and inhibitory avoidance response impairment. Finally, luteolin also increases the level of Mn-SOD, (Cu/Zn)-SOD and glutathione (GSH) in the cortex and hippocampus to reduce the oxidative stress by Abeta (1-40). Taken together, the results in this study suggest that luteolin (5, 10 mg/kg) treatment improves the learning and memory in Abeta (1-40)-induced cognition deficit in rats. The ameliorating mechanisms of luteolin on Abeta (1-40)-induced amnesia may be related to activating the anti-oxidation system.