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A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated to determine hexahydrocurcumin (HHC) levels in mouse plasma, brain, liver, and kidneys using a negative ion mode electrospray ionization (ESI) source. Demonstrating a lower limit of quantification (LLOQ) of 5 ng/mL, the method showed excellent linearity across a concentration range of 5-500 ng/mL in all tested matrices. Precision evaluations reported a coefficient of variation (CV%) of less than 13.19% for both intraday and interday measurements, while accuracy ranged from 95.13 to 105.07% across all quality control levels. HHC extraction recovery was consistently observed between 70.18 and 93.28%, with a CV% deviation of less than 15%. In the pharmacokinetic evaluation of HHC in mice following a single intraperitoneal (IP) or oral administration, a noncompartment analysis was utilized. After IP administration (40 mg/kg), the C max value was 47.90 times higher than that achieved via oral administration. Peak plasma concentrations were observed approximately 5 min post-IP and 15 min post-oral dosing. The observed half-lives after these administrations were approximately 1.52 and 2.17 h for IP and oral routes, respectively. Oral administration revealed a relative bioavailability of only 12.28% compared with the IP route. Furthermore, following IP administration, the half-life values in brain, liver, and kidney were not significantly different but more than the half-life value found in plasma. The liver and kidney exhibited the highest concentrations of HHC, while the brain showed the least, suggesting that the hydrophobic nature of HHC impedes its passage through the blood-brain barrier. This study is the first to provide detailed insights into the pharmacokinetics and tissue distribution characteristics of HHC following oral and IP administration in mice, setting the stage for further focus on HHC as a potential new drug candidate., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Alzheimer's disease (AD) is the most common neurodegenerative disorder in the aging population. An accumulation of amyloid plaques and neurofibrillary tangles causes degeneration of neurons, leading to neuronal cell death. The anthocyanin-rich fraction of black rice ( Oryza sativa L. variety "Luem Pua") bran (AFBRB), extracted using a solution of ethanol and water and fractionated using Amberlite XAD7HP column chromatography, contains a high anthocyanin content (585 mg of cyanidin-3- O -glucoside and 24 mg of peonidin-3- O -glucoside per gram of the rich extract), which has been found to reduce neurodegeneration. This study focused on the neuroprotective effects of AFBRB in Aβ 25-35 -induced toxicity in the human neuroblastoma cell line (SK-N-SH). SK-N-SH was exposed to Aβ 25-35 (10 µM) to induce an AD cell model in vitro. Pretreatment with AFBRB (0.1, 1, or 10 µg/mL) or C3G (20 µM) was conducted for 2 h prior to the treatment with Aβ 25-35 (10 µM) for an additional 24 h. The results indicate that AFBRB can protect against the cytotoxic effect of Aβ 25-35 through attenuation of intracellular ROS production, downregulation of the expression of the proteins Bax, cytochrome c, cleaved caspase-9, and cleaved caspase-3, upregulation of the expression of Bcl-2 in the mitochondrial death pathway, and reduction in the expression of the three major markers of ER stress pathways in similar ways. Interestingly, we found that pretreatment with AFBRB significantly alleviated Aβ-induced oxidative stress, ER stress, and apoptosis in SK-N-SH cells. This suggests that AFBRB might be a potential therapeutic agent in preventing neurodegenerative diseases.

Patients with diabetes require daily medication to maintain blood sugar levels. Nevertheless, the long-term use of antidiabetics can lose efficacy and cause degeneration in some patients. For long-term diabetes care, integrating natural dietary foods and medicine is being considered. This study investigated the impact of SDOs on blood sugar levels and their physiological effects on diabetic rats. We induced diabetes in male Wistar rats with STZ (50 mg/kg) and then administered an oral glucose tolerance test to determine the SDO dosage comparable to glibenclamide. The rats were divided into nine groups: normal, diabetic, and diabetic with insulin (10 U/kg), glibenclamide (0.6 mg/kg), bovine serum albumin (BSA; 200 mg/kg), soy protein isolate (200 mg/kg), or SDOs (50, 100, and 200 mg/kg). Diabetic rats administered SDOs had a higher body weight and serum insulin but a lower blood sugar than diabetic control rats. Biochemical assays indicated lower AST/SGOT, ALT/SGPT, BUN, and triglycerides but higher HDL in the SDO groups. Immunohistochemistry showed that SDOs reduced damaged islet cells, increased beta-cell size, and improved insulin levels while decreasing alpha cell size and glucagon. The vascular effects of SDOs were like those of normal control treatment and insulin treatment in diabetic rats. SDOs, a yellow silk protein, show potential for long-term diabetes care.

Pelargonic acid vanillylamide (PAVA) has been shown to reduce hepatic lipid accumulation in an obese rat model, however the underlying mechanism responsible for regulating lipid metabolism remains unclear. This study investigated the molecular mechanisms invoked by PAVA in regulating lipogenesis, autophagy, and endoplasmic reticulum (ER) stress in obese rats. Male Sprague-Dawley rats were fed on a diet consisting of 65.26% fat (16 weeks) and HepG2 cells were incubated with 200 μM oleic acid (OA) plus 100 μM palmitic acid (PA) for 48 h. These treatments resulted in a steatosis model. PAVA was shown to reduce fat deposition in hepatocytes in HepG2 by reducing lipotoxicity, the triglyceride content, the expression of sterol regulatory element binding protein 1c (SREBP-1c) and fatty acid synthase (FASN). PAVA also significantly reduced the calcium level and the expression of calpain 2 and upregulated the expression of Atg7 in comparison to the HFD group. In addition, PAVA was shown to significantly decrease the expression of autophagy pathway-related proteins including LC3 and p62. Treatment with PAVA (1 mg/day) reduced the expressions of ER stress markers Bip, ATF6 (p50), p-IRE1/IRE1, p-eIF2α/eIF2α, pJNK, CHOP and cleaved CASP12. In conclusion, PAVA ameliorated obesity induced hepatic steatosis by attenuating defective autophagy and ER stress pathways., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Obesity is well-established as a common comorbidity in ischemic stroke. The increasing evidence has revealed that it also associates with the exacerbation of brain pathologies, resulting in increasingly severe neurological outcomes following cerebral ischemia and reperfusion (I/R) damage. Mechanistically, pyroptosis and necroptosis are novel forms of regulated death that relate to the propagation of inflammatory signals in case of cerebral I/R. Previous studies noted that pyroptotic and necroptotic signaling were exacerbated in I/R brain of obese animals and led to the promotion of brain tissue injury. This study aimed to investigate the roles of melatonin on pyroptosis, necroptosis, and pro-inflammatory pathways occurring in the I/R brain of obese rats. Male Wistar rats were given a high-fat diet for 16 weeks to induce the obese condition, and then were divided into 4 groups: Sham-operated, I/R treated with vehicle, I/R treated with melatonin (10 mg/kg), and I/R treated with glycyrrhizic acid (10 mg/kg). All drugs were administered via intraperitoneal injection at the onset of reperfusion. The development of neurological deficits, cerebral infarction, histological changes, neuronal death, and glial cell hyperactivation were investigated. This study revealed that melatonin effectively improved these detrimental parameters. Furthermore, the processes of pyroptosis, necroptosis, and inflammation were all diminished by melatonin treatment. A summary of the findings is that melatonin effectively reduces ischemic brain pathology and thereby improves post-stroke outcomes in obese rats by modulating pyroptosis, necroptosis, and inflammation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The proliferation and migration of vascular smooth muscle cells (VSMCs) play vital roles in the pathogenesis of atherosclerosis and hypertension. It has been proposed and verified that hexahydrocurcumin (HHC), a metabolite form of curcumin, has cardiovascular protective effects. This study examined the effect of HHC on angiotensin II (Ang II)-induced proliferation, migration, and inflammation in rat aortic VSMCs and explored the molecular mechanisms related to the processes. The results showed that HHC significantly suppressed Ang II-induced proliferation, migration, and inflammation in VSMCs. HHC inhibited Ang II-induction of the increase in cyclin D1 and decrease in p21 expression in VSMCs. Moreover, HHC attenuated the generation of reactive oxygen species (ROS), and the expression of nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and matrix metalloproteinases-9 (MMP9) in Ang II-induced VSMCs. The proliferation, migration, inflammation, and ROS production were also inhibited by GKT137831 (NADPH oxidase, NOX1/4 inhibitor) and the combination of HHC and GKT137831. In addition, HHC restored the Ang-II inhibited expression of peroxisome proliferator-activated receptor-γ (PPAR-γ) and peroxisome proliferator activated receptor-γ coactivator-1α (PGC-1α). These findings indicate that HHC may play a protective role in Ang II-promoted proliferation, migration, and inflammation by suppressing NADPH oxidase mediated ROS generation and elevating PPAR-γ and PGC-1α expression. See also Figure 1(Fig. 1)., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 Panthiya et al.)

Insulin resistance is a salient player in the pathogenesis of obesity and its related abnormal glucose-insulin homeostasis. Red rice bran extract (RRBE) demonstrates several bioactive phytochemicals with anti-diabetic properties. However, little is known about its molecular mechanisms. Therefore, the present study was designed to investigate the anti-insulin resistant mechanisms of RRBE in a model of high-fat diet (HFD)-induced insulin resistance. In this study, mice were randomly divided into four groups: low-fat diet with distilled water (Group L), HFD with distilled water (Group H), HFD with 0.5 g/kg RRBE, and HFD with 1 g/kg RRBE. Metabolic parameters, histological changes in the pancreas, and gene expression levels were evaluated after treating HFD-fed mice with RRBE for six weeks. Mice from Group H exhib-ited significantly higher blood glucose levels prior to and after an oral glucose tolerance test, fasting serum insulin levels, islet size, pancreatic insulin expression levels, and lower skeletal muscle insulin-degrading enzyme (IDE) expression levels compared to Group L. In contrast, these were all significantly restored in the RRBE-treated groups. Also, RRBE treatment was found to upregulate the expression of insulin receptor substrate (IRS) and glucose transporter (GLUT) genes in the adipose tissues and GLUT genes in the muscles and livers of HFD-fed mice. According to our results, RRBE may ameliorate abnormal glucose-insulin metabolism by modulating the expression of insulin, IDE, IRS, and GLUT genes in the major metabolic target tissues of mice after being fed with HFD., Competing Interests: AUTHOR DISCLOSURE STATEMENT The authors declare no conflict of interest., (Copyright © 2022 by The Korean Society of Food Science and Nutrition. All rights Reserved.)

Background: Festidinol is a flavan-3-ol which has been shown to reduce advanced glycation end products (AGEs) and reactive oxygen species, both of which play a crucial role in the pathology of many neurodegenerative diseases., Purpose: This study aimed to investigate the effects of festidinol on oxidative stress, amyloidogenesis, phosphorylated tau (pTau) expression, synaptic function, and cognitive impairment, and the potential mechanisms involved, in a mouse model with an Alzheimer-like pathology., Methods: D-galactose (150 mg/kg) and aluminum chloride (10 mg/kg) were injected intraperitoneally into 40 mice for 90 days to generate an AD mouse model with cognitive impairment. Festidinol (30 mg/kg) and donepezil (5 mg/kg) were then administered orally for 90 days after which behavior and molecular changes in the brain were measured., Results: The aluminum accumulated and the expression of the cell senescence marker P16 increased after exposure to D-galactose and AlCl 3 (2.5 ± 0.5 mg/kg, 149.1 ± 28.1% of control, respectively). Festidinol markedly decreased the escape latency (8.7 ± 4.3 s) and increased the number of platform crossings (8 ± 1.4 time) in the Morris water maze test. Superoxide dismutase activity was significantly elevated after festidinol administration, however there were significant reductions in the levels of 4‑hydroxy-2-nonenal, receptor for advanced glycation end products, phosphorylated nuclear factor kappa-light-chain-enhancer of activated B cells (pNF-κB), and nuclear factor of activated T cells 1 (NFAT1). Festidinol attenuated amyloid beta production by reducing the mRNA of beta-site APP cleaving enzyme 1 (BACE1). Festidinol also significantly decreased the expression of pTau and phosphorylated glycogen synthase kinase 3 (148.6 ± 37.6% of control, 125.3 ± 22.6% of control, respectively)., Conclusion: Festidinol can ameliorate learning and memory impairments by modulating amyloidogenesis, tau hyperphosphorylation, cholinergic activity, neuroinflammation, and oxidative stress, and by regulating the brain-derived neurotrophic factor signaling pathway., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Hexahydrocurcumin (HHC), a major metabolite of curcumin, possesses several biological activities such as antioxidant, anti-inflammation, and cardioprotective properties. This study aimed to investigate the effect of HHC on high blood pressure, vascular dysfunction, and remodeling induced by N-nitro L-arginine methyl ester (L-NAME) in rats. Male Wistar rats (200-250 g) received L-NAME (40 mg/kg) via drinking water for seven weeks. HHC at doses of 20, 40 or 80 mg/kg or enalapril 10 mg/kg was orally administered for the last three weeks. Blood pressure was measured weekly. Rats induced with L-NAME showed the development of hypertension, vascular dysfunction, and remodeling as demonstrated by an increase in wall thickness, cross-sectional area, and collagen deposition in the aorta. The overexpression of nuclear factor kappa B (NF-кB), vascular cell adhesion molecule 1 (VCAM1), intercellular adhesion molecule 1 (ICAM1), tumor necrosis factor-alpha (TNF-α), phosphorylated-extracellular-regulated kinase 1/2 (p-ERK1/2), phosphorylated-c-Jun N-terminal kinases (p-JNK), phosphorylated-mitogen activated protein kinase p38 (p-p38), transforming growth factor-beta 1 (TGF-β1), matrix metalloproteinase-9 (MMP-9) and collagen type 1 was observed in L-NAME-induced hypertensive rats. Increased oxidative stress markers, decreased plasma nitric oxide (NO) levels and the down-regulation of endothelial nitric oxide synthase (eNOS) expression in aortic tissues were also found in L-NAME-induced rats. Moreover, L-NAME-induced rats showed enhanced synthetic protein expression in aortic tissues. These alterations were suppressed in hypertensive rats treated with HHC or enalapril. The present study shows that HHC exhibited antihypertensive effects by improving vascular function and ameliorated the development of vascular remodeling. The responsible mechanism may involve antioxidant and anti-inflammation potential., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Agomelatine, a novel antidepressant, is a melatonin MT receptor agonist and serotonin 5HT 2C receptor antagonist. In this study, agomelatine was used to investigate the molecular mechanisms of hippocampal aging associated with endoplasmic reticulum (ER) stress, mitochondrial dysfunction, and apoptosis, all of which led to short-term memory impairment., Method: Hippocampal aging was induced in male Wistar rats by d-galactose (D-gal) intraperitoneal injection (100 mg/kg) for 14 weeks. During the last 4 weeks of D-gal treatment, rats were treated with agomelatine (40 mg/kg) or melatonin (10 mg/kg). At the end of the experiment, all rats were assessed for short-term memory by using the Morris water maze test. Subsequently, rats were sacrified and the hippocampus was removed from each rat for determination of reactive oxygen species (ROS), malondialdehyde (MDA), and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays; and immunohistochemistry related to ER stress, mitochondrial dysfunction, and apoptosis., Results: Agomelatine suppressed the expression of the aging-related proteins P16 and receptor for advanced glycation endproducts (RAGE), the expression of NADPH oxidase (NOX) 2 and 4, and ROS production. This treatment also shifted the morphology of astrocytes and microglia toward homeostasis. Furthermore, agomelatine decreased inositol-requiring enzyme 1 (pIRE1), protein kinase R-like endoplasmic reticulum kinase (pPERK), and chaperone binding immunoglobulin protein (BiP), leading to suppression of ER stress markers C/EBP homologous protein (CHOP) and caspase-12. Agomelatine reduced Ca 2+ from the ER and stabilized the mitochondrial membrane stability, which was denoted by the BCL2 Associated X (Bax)/B-cell lymphoma 2 (Bcl2) balance. Agomelatine decreased cleaved caspase-3 production and the Terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL)-positive area, and glutamate excitotoxicity was prevented via suppression of N-methyl-d-aspartate (NMDA) receptor subunit expression. Agomelatine exhibited effects that were similar to melatonin., Conclusion: Agomelatine improved neurodegeneration in a rat model of hippocampal aging by attenuating ROS production, ER stress, mitochondrial dysfunction, excitotoxicity, and apoptosis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Oxidized low-density lipoprotein (ox-LDL) not only causes hyperlipidemia and contributes to atherosclerosis but also induces the endothelial dysfunction that leads to cardiovascular diseases. The nuclear factor-kappa B (NF-κB) pathway plays a key role in many chronic disorders and is a transcriptional factor in various inflammatory responses. The present study aimed to investigate the synergistic effects of pelargonic acid vanillylamide (PAVA) and rosuvastatin (RSV) on ox-LDL-induced inflammatory responses in human vascular endothelial cells (HUV-EC-C). HUV-EC-C were pretreated with PAVA or RSV and their combination for 2 h followed by ox-LDL for 24 h. The MTT assay was used to measure mitochondrial function. The DCFH-DA assay was used to evaluate oxidative phosphorylation, and western blotting was used to measured NF-κB/NLRP3 and related signaling pathways in HUV-EC-C. Ox-LDL induced lectin-type oxidized LDL receptor 1 (LOX-1) expression, NADPH oxidase 4 activation, and the overexpression of reactive oxygen species, which were inhibited by pretreatment with the combination of PAVA and RSV. Moreover, PAVA and RSV inhibited ox-LDL-induced NF-κBp65 activation. Ox-LDL induced NF-κB/NLRP3 pathway activation by inducing C-reactive protein expression, NLRP3 activation, caspase-1 activation, and IL-1β secretion, which were inhibited by pretreatment with the combination of PAVA and RSV. The combination of PAVA and RSV reduced ox-LDL-induced recruitment of monocytes to the site of inflammation, inhibited activation of the NLRP3 inflammasome, and ameliorated the impairment of cell-cell junctions through the NF-κB pathway. Our results suggest that the synergistic effects of PAVA and RSV provide a novel mechanism for the treatment of cardiovascular diseases., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Amyloidogenesis is a fundamental step of amyloid beta (Aβ) generation-induced toxicity that is commonly reported to disrupt neuronal circuits, function and survival in Alzheimer's disease (AD). The neuroprotective effect of 5,6,7,4'-tetramethoxyflavanone (TMF) from Chormolaela odorata extract on brain degeneration and amyloidogenesis has previously been demonstrated. However, the mechanistic evidence for TMF's effects is still unclear. In this study, we evaluated the neuroprotective effect of TMF in Aβ 25-35 -induced toxicity in SK-N-SH neuroblastoma cells. Herein, we demonstrated that TMF exhibited potent antioxidant activity and significantly increased cell viability and decreased ROS production in a dose-dependent manner. Moreover, TMF reversed the effect of Aβ 25-35 , which caused energy deprivation and apoptosis, by decreasing the ratio of Bax/Bcl-x L and reducing mitochondrial membrane potential (Δψ m ), caspase-3 expression, apoptotic cells, and attenuating glucose transporter (Glut-3) expression. In addition, TMF protected against Aβ 25-35 -induced cellular senescence by attenuating β-galactosidase, p-21 and p-53 expression and promoted the expression of Sirt-1 and p-Rb. In addition, the effects of TMF on Aβ 25-35 toxicity were related to the upregulation of phase II antioxidant and nuclear factor erythroid 2-related factor-2 (Nrf2) signaling, including superoxide dismutase (SOD), heme oxygenase (HO)-1, and nuclear translocation of Nrf2. Finally, we also found that TMF attenuated Aβ 25-35 -reduced synaptic plasticity by increasing the expression of synaptophysin and PSD-95, which was correlated with a decrease in acetylcholine esterase (AChE). Importantly, we found that the protective effects of TMF on Aβ 25-35 were bidirectional, including marked inhibition of NADPH oxidase (NOX)-4 activity and partial activation of Sirt-1, which occurred prior to a reduction in the negative responses. Therefore, TMF may be useful for treating Aβ toxicity in AD., (Copyright © 2021 Jumnongprakhon et al.)

This study aimed to investigate the effects of morin on cerebral damage and blood-brain barrier (BBB) integrity in a middle cerebral artery occlusion (MCAO) and reperfusion model. Wistar rats were exposed to MCAO for 2 h, followed by reperfusion. Thirty mg/kg of morin was administered via intraperitoneal injection at the different time points: before ischemia, during ischemia, and at reperfusion. The rats were divided into five groups, including sham, vehicle, and three groups of morin. Twenty-four hours after reperfusion, the rats were tested for neurological deficits, and the brains were harvested to assess brain damage. In addition, brains were harvested 72 h to determine BBB disruption. We found that morin significantly reduced reactive oxygen species production and lipid peroxidation. It also decreased inflammation via reducing the expression of Toll-like receptor 4, nuclear factor kappa-beta. Morin ameliorated cerebral damage and reduced apoptosis through decreasing the cerebral infarct size, including apoptotic cell death. Moreover, morin decreased the BBB damage via reducing Evans blue extravasation, neutrophil infiltration, and increasing tight junction protein expression. Therefore, morin protected against cerebral and BBB damage by attenuating oxidative stress, inflammation, and apoptosis in MCAO and reperfusion models.

Nonalcoholic fatty liver disease (NAFLD) is a chronic disease that causes morbidity associated with metabolic syndrome. NAFLD is a worldwide problem and represents a major cause of liver injury, which can lead to liver cell death. We investigated the effects of nonivamide (pelargonic acid vanillylamide, PAVA; 1 mg/kg) and rosuvastatin (RSV; 10 mg/kg) on hepatic steatosis induced by a high-fat diet (HFD). Male Sprague-Dawley rats were fed a HFD for 16 weeks then received PAVA or RSV for 4 additional weeks. We examined the metabolic parameters, function, fat content, histological alterations, reactive oxygen species production, and apoptotic cell death of the liver, in addition to the expression of the following important molecules: transient receptor potential cation channel subfamily V member 1 (TRPV1) phosphorylation of sterol regulatory element binding protein (pSREBP-1c/SREBP-1c), total and membrane glucose transporter 2 (GLUT2), 4-hydroxynonenal (4-HNE), and cleaved caspase-3. HFD-induced hepatic steatosis was associated with significantly increased morphological disorganization, injury markers, oxidative stress, lipid peroxidation, and apoptosis. However, metabolic dysfunction and hepatic injury were reduced by RSV and PAVA treatment. PAVA regulated lipid deposition, improved insulin resistance, and decreased oxidative stress and apoptotic cell death. Therefore, PAVA represents a promising therapeutic approach for treating metabolic disorders in patients with NAFLD., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest., (Copyright © 2020 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

This study investigated the long-term effects of dihydrocapsaicin (DHC)-induced angiogenesis and improved functional outcomes in cerebral ischemia and reperfusion (I/R) rats. Middle cerebral artery occlusion was induced in I/R rats for 2 h, followed by reperfusion. The animals were divided into three groups: sham, I/R + vehicle, and I/R + DHC (10 mg/kg body weight). Fourteen days after I/R injury, the DHC-treated I/R rats had decreased neurological deficit scores, infarct volume, and brain morphology changes. DHC-induced angiogenesis significantly increased the expression of angiogenic factor proteins, such as hypoxia inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF), and matrix metalloprotease 9 (MMP-9), at 3 d and 14 d following I/R and also increased the expression of angiogenic inhibitors, such as angiopoietin 1 (Ang-1) and its receptor tyrosine kinase (Tie-2), at 14 d following reperfusion. DHC-mediated angiogenesis was confirmed by a significant increase in positive BrdU labeling that co-localized with the von Willebrand factor (an endothelial cell marker) at 14 d after I/R. Furthermore, rotarod and pole tests demonstrated that DHC promoted functional recovery when compared with the vehicle group. Thus, the results reveal that DHC mediates angiogenesis and functional recovery after an ischemic stroke., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest., (Copyright © 2020 The Authors. Production and hosting by Elsevier B.V. All rights reserved.)

Long-term exposure to high glucocorticoid levels induces memory impairment and neurodegeneration in Alzheimer's disease (AD) by increasing the expression of amyloid β and tau hyperphosphorylation (pTau). Previous studies showed beneficial effects of flavonoids in neurodegenerative models. 5,6,7,4'-tetramethoxyflavanone (TMF) is one of the active ingredients in Chromolaena odorata (L.), which R. M. King and H. Rob discovered in Thailand. This study focused on the effects of TMF on dexamethasone (DEX)-induced neurodegeneration, amyloidogenesis, pTau expression, neuron synaptic function, and cognitive impairment and the potential mechanisms involved. Mice were intraperitoneally administered DEX for 28 days before being treated with TMF for 30 days. The mice were randomly divided into six groups (twelve mice per group): control; TMF administration (40 mg/kg); pioglitazone administration (20 mg/kg); DEX administration (60 mg/kg); DEX administration plus TMF; and DEX administration plus pioglitazone. Behavioral tests showed that TMF significantly attenuated the memory impairment triggered by DEX. Consistently, TMF reduced DEX-induced amyloid beta production by reducing the expression of beta-site APP cleaving enzyme 1 (BACE1) and presenilin 1 (PS1), whereas it increased the gene expression of a disintegrin and metalloprotease 10 (ADAM10). TMF treatment also decreased pTau expression, inhibited phosphonuclear factor-kappa B (pNF-kB) and inhibited glycogen synthase kinase 3 (GSK-3) activity by increasing GSK3 phosphorylation (pGSK3). In addition, TMF also improved synaptic function by increasing the expression of synaptophysin (Syn) and postsynaptic density protein 95 (PSD95) while decreasing acetylcholine esterase activity. Conclusively, TMF provided neuroprotection against DEX-induced neurodegeneration. These findings suggest that TMF might have potential as a therapeutic drug for AD., (Copyright © 2020 Pakdeepak et al.)

Background and Objectives: The potent, endothelium-independent, vasorelaxant effect of ethyl rosmarinate, an ester derivative of rosmarinic acid, makes it of interest as an alternative therapeutic agent for use in hypertension. This study was designed to investigate the effect of ethyl rosmarinate on N ω -nitro-L-arginine methyl ester (L-NAME)-induced hypertensive rats. Materials and Methods: L-NAME was given orally to male Wistar rats for 6 weeks to induce hypertension concurrently with treatment of ethyl rosmarinate at 5, 15, or 30 mg/kgor enalapril at 10 mg/kg Systolic blood pressure (SBP), heart rate, and body weight of all experimental groups were recorded weekly, while the vascular sensitivity and histological changes of the aorta were evaluated at the end of the experiment. Results: For all treatment groups, the data indicated that ethyl rosmarinate significantly attenuated the SBP in hypertensive rats induced by L-NAME, with no significant differences in heart rate and body weight. In addition, the response of vascular sensitivity to acetylcholine (ACh) was improved but there was no significant difference in the response to sodium nitroprusside (SNP). Furthermore, the sensitivity of the aorta to phenylephrine (PE) was significantly decreased. The thickness of the aortic wall did not differ between groups but the expression of endothelial nitric oxide synthase (eNOS) was increased in ethyl rosmarinate- and enalapril-treated groups compared with the hypertensive group. Conclusions: Ethyl rosmarinate is an interesting candidate as an alternative treatment for hypertension due to its ability to improve vascular function and to increase the expression of eNOS similar to enalapril which is a drug commonly used in hypertension.

Tiliacorinine 12'-O-acetate is a modified analog of Tiliacorinine, a major compound in Tiliacora triandra. The present study explored the vasorelaxation property of tiliacorinine 12'-O-acetate and its mechanism in isolated rat aorta using the organ bath technique. Tiliacorinine 12'-O-acetate exhibited concentration-dependent (10 -15 -10 -3.5 M) vasorelaxation in endothelium-intact rings (E max  = 93.53 ± 2.79%) and endothelium-denuded rings (E max  = 74.31 ± 5.09%). The effects of tiliacorinine 12'-O-acetate were attenuated by pre-incubation with N(ω)-nitro-l-arginine methyl ester (L-NAME, endothelium nitric oxide synthase inhibitor) (100 μM), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, soluble quanylylcyclase inhibitor) (1 μM), and 4-aminopyridine (1 mM, K v channel blocker). However, this effect was not impacted by indomethacin (10 μM, cyclooxygenase inhibitor), tetraethylammonium (5 mM, K ca channel blocker), barium chloride (1 mM, K IR channel blocker), or glibenclamide (10 μM, K ATP channel blocker). Moreover, pretreatment with tiliacorinine 12'-O-acetate reduced the effect of L-NAME (100 μM) on acetylcholine-induced vasorelaxation. Tiliacorinine 12'-O-acetate showed inhibitory effects on CaCl 2 -induced contracted rings and reduced the contraction induced by phenylephrine (10 μM) and caffeine (20 mM) in a Ca 2+ -free solution. The results of this study suggest that tiliacorinine 12'-O-acetate induced endothelium-dependent vasorelaxation through the eNOS/NO/sGC pathway, and also induced endothelium independent vasorelaxation involving the modulation of sGC activity, K v channels, Ca 2+ influx through Ca 2+ channels and intracellular Ca 2+ release. The data concerning the benefits of tiliacorinine 12'-O-acetate might be further investigated for the application of tiliacorinine 12'-O-acetate as an antihypertensive compound., (Copyright © 2018 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Cyanidin is polyphenolic pigment found in plants. We have previously demonstrated that cyanidin protects nerve cells against Aβ 25-35 -induced toxicity by decreasing oxidative stress and attenuating apoptosis mediated by both the mitochondrial apoptotic pathway and the ER stress pathway. To further elucidate the molecular mechanisms underlying the neuroprotective effects of cyanidin, we investigated the effects of cyanidin on neuroinflammation mediated by the TLR4/NOX4 pathway in Aβ 25-35 -treated human neuroblastoma cell line (SK-N-SH). SK-N-SH cells were exposed to Aβ 25-35 (10 μmol/L) for 24 h. Pretreatment with cyanidin (20 μmol/L) or NAC (20 μmol/L) strongly inhibited the NF-κB signaling pathway in the cells evidenced by suppressing the degradation of IκBα, translocation of the p65 subunit of NF-κB from the cytoplasm to the nucleus, and thereby reducing the expression of iNOS protein and the production of NO. Furthermore, pretreatment with cyanidin greatly promoted the translocation of the Nrf2 protein from the cytoplasm to the nucleus; upregulating cytoprotective enzymes, including HO-1, NQO-1 and GCLC; and increased the activity of SOD enzymes. Pretreatment with cyanidin also decreased the expression of TLR4, directly improved intracellular ROS levels and regulated the activity of inflammation-related downstream pathways including NO production and SOD activity through TLR4/NOX4 signaling. These results demonstrate that TLR4 is a primary receptor in SK-N-SH cells, by which Aβ 25-35 triggers neuroinflammation, and cyanidin attenuates Aβ-induced inflammation and ROS production mediated by the TLR4/NOX4 pathway, suggesting that inhibition of TLR4 by cyanidin could be beneficial in preventing neuronal cell death in the process of Alzheimer's disease.

Beta-amyloid (Aβ) peptide, the hallmark of Alzheimer's disease (AD), invokes a cascade of oxidative damage to neurons and eventually leads to neuronal death. This study evaluated the protective effects of lutein extract from yellow cocoons of Bombyx mori, and its underlying mechanisms against was investigated to assess its protective effects and the underlying mechanisms against Aβ 25-35 -induced neuronal cell death in cultured rat pheochromocytoma (PC12) cells. Aβ 25-35 -induced neuronal toxicity is characterized by decrease in cell viability, increase in intracellular reactive oxygen species (ROS) production, activation of mitochondrial death pathway, and activation the phospholyration of mitogen-activated protein kinase (MAPKs) pathway. Pretreatment with silk lutein extract significantly attenuated Aβ 25-35 -induced loss of cell viability, apoptosis, MAPKs pathway activation and ROS production. Taken together, our present study suggests that silk lutein extract protects PC12 cells from Aβ 25-35 -induced neurotoxicity via the reduction of the ROS production, and subsequent attenuation of the mitochondrial death pathway and reduces the activation of the MAPK kinase pathways. This compound might beneficial as potential therapeutic agent to prevent or retard the development and progression of AD., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

The purpose of the present experiment was to investigate whether hexahydrocurcumin (HHC) attenuates brain damage and improves functional outcome via the activation of antioxidative activities, anti-inflammation, and anti-apoptosis following cerebral ischemia/reperfusion (I/R). In this study, rats with cerebral I/R injury were induced by a transient middle cerebral artery occlusion (MCAO) for 2 h, followed by reperfusion. The male Wistar rats were randomly divided into five groups, including the sham-operated, vehicle-treated, 10 mg/kg HHC-treated, 20 mg/kg HHC-treated, and 40 mg/kg HHC-treated I/R groups. The animals were immediately injected with HHC by an intraperitoneal administration at the onset of cerebral reperfusion. After 24 h of reperfusion, the rats were tested for neurological deficits, and the pathology of the brain was studied by 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin and eosin (H&E) staining, and terminal deoxynucleotidyltransferase UTP nick end labeling (TUNEL) staining. In addition, the brain tissues were prepared for protein extraction for Western blot analysis, a malondialdehyde (MDA) assay, a nitric oxide (NO) assay, a superoxide dismutase (SOD) assay, a glutathione (GSH) assay, and a glutathione peroxidase (GSH-Px) assay. The data revealed that the neurological deficit scores and the infarct volume were significantly reduced in the HHC-treated rats at all doses compared to the vehicle group. Treatment with HHC significantly attenuated oxidative stress and inflammation, with a decreased level of MDA and NO and a decreased expression of NF-κB (p65) and cyclooxygenase-2 (COX-2) in the I/R rats. HHC also evidently increased Nrf2 (nucleus) protein expression, heme oxygenase-1 (HO-1) protein expression, the antioxidative enzymes, and the superoxide dismutase (SOD) activity. Moreover, the HHC treatment also significantly decreased apoptosis, with a decrease in Bax and cleaved caspase-3 and an increase in Bcl-XL, which was in accordance with a decrease in the apoptotic neuronal cells. Therefore, the HHC treatment protects the brain from cerebral I/R injury by diminishing oxidative stress, inflammation, and apoptosis. The antioxidant properties of HHC may play an important role in improving functional outcomes and may offer significant neuroprotection against I/R damage.

This study investigated the effect of dihydrocapsaicin (DHC) on cerebral and blood brain barrier (BBB) damage in cerebral ischemia and reperfusion (I/R) models. The models were induced by middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion. The rats were divided into five groups: sham, or control group; vehicle group; and 2.5 mg/kg, 5 mg/kg, and 10 mg/kg BW DHC-treated I/R groups. After 24 h of reperfusion, we found that DHC significantly reduced the area of infarction, morphology changes in the neuronal cells including apoptotic cell death, and also decreased the BBB damage via reducing Evan Blue leakage, water content, and ultrastructure changes, in addition to increasing the tight junction (TJ) protein expression. DHC also activated nuclear-related factor-2 (Nrf2) which involves antioxidant enzymes like superoxide dismutase (SOD) and glutathione peroxidase (GPx), and significantly decreased oxidative stress and inflammation via down-regulated reactive oxygen species (ROS), NADPH oxidase (NOX2, NOX4), nuclear factor kappa-beta (NF-ĸB), and nitric oxide (NO), including matrix metalloproteinases-9 (MMP-9) levels. DHC protected the cerebral and the BBB from I/R injury via attenuation of oxidative stress and inflammation. Therefore, this study offers to aid future development for protection against cerebral I/R injury in humans.

Methamphetamine (METH) is a neurotoxic drug that causes brain damage by inducing neuronal and glial cell death together with glial cell hyperactivity-mediated progressive neurodegeneration. Previous studies have shown that METH induced glial cell hyperactivity and death via oxidative stress, the inflammatory response, and endoplasmic reticulum stress (ER stress) mechanisms, and melatonin could reverse these effects. However, the exact mechanism of the protective role of melatonin in METH-mediated ER stress has not been understood. This study investigated the protective effect of melatonin against METH toxicity-mediated ER stress in glial cells. Our study demonstrated that METH increased glial cell toxicity related to METH-induced ER stress by stimulating the unfolded protein response (UPR) to activate the expression of ER stress transducers, including phosphorylated double-stranded RNA-activated protein kinase (PKR)-like ER kinase (p-PERK), activating transcription factor (ATF6), and phosphorylated inositol-requiring enzyme 1 (p-IRE1). Moreover, the expression of binding immunoglobulin protein (Bip), CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, phosphorylated eukaryotic translation initiation factor 2 alpha (p-eIF2α) and spliced X-box-binding protein-1 (XBP-1) mRNA were also increased. Melatonin reduced ER stress induced by METH toxicity by reducing the expression of ER stress response genes and proteins in a concentration-dependent manner. In addition, melatonin promoted the expression of Bip chaperone in a concentration-dependent manner. Taken together, our findings suggest that melatonin can protect against ER stress-induced glial cell death induced by METH.

Angiotensin II (Ang II) causes oxidative stress and vascular inflammation, leading to vascular endothelial cell dysfunction, and is associated with the development of inflammatory cardiovascular diseases such as atherosclerosis. Therefore, interventions of oxidative stress and inflammation may contribute to the reduction of cardiovascular diseases. Cyanidin-3-glucoside (C3G) plays a role in the prevention of oxidative damage in several diseases. Here, we investigated the effect of C3G on Ang II-induced oxidative stress and vascular inflammation in human endothelial cells (EA.hy926). C3G dose-dependently suppressed the free radicals and inhibited the nuclear factor-kappa B (NF-κB) signaling pathway by protecting the degradation of inhibitor of kappa B-alpha (IκB-α), inhibiting the expression and translocation of NF-κB into the nucleus through the down-regulation of NF-κB p65 and reducing the expression of inducible nitric oxide synthase (iNOS). Pretreatment with C3G not only prohibited the NF-κB signaling pathway but also promoted the activity of the nuclear erythroid-related factor 2 (Nrf2) signaling pathway through the upregulation of endogenous antioxidant enzymes. Particularly, we observed that C3G significantly enhanced the production of superoxide dismutase (SOD) and induced the expression of heme oxygenase (HO-1). Our findings confirm that C3G can protect against vascular endothelial cell inflammation induced by AngII. C3G may represent a promising dietary supplement for the prevention of inflammation, thereby decreasing the risk for the development of atherosclerosis., (Copyright © 2016. Published by Elsevier Ireland Ltd.)

Sericin-derived oligopeptides obtained from silk cocoons were investigated for the in vivo hypotensive effect and investigated for the underlying mechanism involved in vasodilation in isolated rat thoracic aorta. In normotensive anesthetized rats, oligopeptides induced an immediate and transient hypotensive activity. In rat aortic rings, oligopeptides induced a concentration-dependent vasorelaxation in vessels precontracted with both KCl and phenylephrine (PE) with endothelium-intact or endothelium-denuded rings. In endothelium-intact rings, pretreatment with N ω -Nitro-L-arginine methyl ester hydrochloride (L-NAME, 100 µM), an inhibitor of the NO synthase (NOS) or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, 1 µM), a selective inhibitor of the guanylyl cyclase enzyme, significantly reduced the relaxant effect of oligopeptides. However, indomethacin, an inhibitor of the cyclooxygenase, had no effect on oligopeptides-induced relaxation. In addition, pretreatment with tetraethylammonium (TEA, 5 mM) reduced the maximal relaxant effect induced by oligopeptides. By contrast, relaxation was not affected by 4-aminopyridine (4-AP, 1 mM), glibenclamide (10 µM), or barium chloride (BaCl2, 1 mM). In depolarization Ca(2+)-free solution, oligopeptides inhibited calcium chloride- (CaCl2-) induced contraction in endothelium-denuded rings in a concentration-dependent manner. Nevertheless, oligopeptides attenuated transient contractions in Ca(2+)-free medium containing EGTA (1 mM) induced by 1 µM PE, but they were not affected by 20 mM caffeine. It is obvious that potent vasodilation effect of oligopeptides is mediated through both the endothelium and the vascular smooth muscle.

Aim: To investigate the effects of hexahydrocurcumin (HHC), and its combination with 5-fluorouracil (5-FU) on dimethylhydrazine (DMH)-induced colon cancer in rats., Methods: Male Wistar rats weighing 100-120 g were used as subject models. Aberrant crypt foci (ACF), early preneoplastic lesions of colon cancer, were induced by subcutaneous injection of DHM (40 mg/kg) twice a week for two weeks. After the first DMH injection, rats were treated daily with vehicle (n = 12), curcumin (CUR) (50 mg/kg) (n = 12), HHC (50 mg/kg) orally (n = 12), and treated weekly with an intraperitoneal injection of 5-FU (50 mg/kg) (n = 12), or a combination of 5-FU plus CUR (n = 12) and HHC (n = 12) at the same dosage(s) for 16 wk. The total number of ACF and large ACF were assessed. Cyclooxygenase (COX)-1 and COX-2 expression were detected by immunohistochemistry in colon tissues. The quantitative data of both COX-1 and COX-2 expression were presented as the percentage of number of positive-stained cells to the total number of cells counted. Apoptotic cells in colon tissues were also visualized using the dUTP-biotin nick end labeling method. Apoptotic index (AI) was determined as the percentage of labeled nuclei with respect to the total number of nuclei counted., Results: The total number of ACF was highest in the DMH-vehicle group (1558.20 ± 17.37), however, the number of ACF was significantly reduced by all treatments, 5-FU (1231.20 ± 25.62 vs 1558.20 ± 17.37, P < 0.001), CUR (1284.20 ± 25.47 vs 1558.20 ± 17.37, P < 0.001), HHC (1086.80 ± 53.47 vs 1558.20 ± 17.37, P < 0.001), DMH-5-FU + CUR (880.20 ± 13.67 vs 1558.20 ± 17.37, P < 0.001) and DMH-5-FU + HHC (665.80 ± 16.64 vs 1558.20 ± 17.37, P < 0.001). Interestingly, the total number of ACF in the combined treatment groups, the DMH-5-FU + CUR group (880.20 ± 13.67 vs 1231.20 ± 25.62, P < 0.001; 880.20 ± 13.67 vs 1284.20 ± 25.47, P < 0.001) and the DMH-5-FU + HHC group (665.80 ± 16.64 vs 1231.20 ± 25.62, P < 0.001; 665.80 ± 16.64 vs 1086.80 ± 53.47, P < 0.001) were significantly reduced as compared to 5-FU or each treatment alone. Large ACF were also significantly reduced in all treatment groups, 5-FU (111.00 ± 7.88 vs 262.20 ± 10.18, P < 0.001), CUR (178.00 ± 7.33 vs 262.20 ± 10.18, P < 0.001), HHC (186.60 ± 21.51 vs 262.20 ± 10.18, P < 0.001), DMH-5-FU + CUR (122.00 ± 5.94 vs 262.20 ± 10.18, P < 0.001) and DMH-5-FU + HHC (119.00 ± 17.92 vs 262.20 ± 10.18, P < 0.001) when compared to the vehicle group. Furthermore, in the DMH-5-FU + CUR and DMH-5-FU + HHC groups the formation of large ACF was significantly reduced when compared to CUR (122.00 ± 5.94 vs 178.00 ± 7.33, P < 0.005) or HHC treatment alone (119.00 ± 17.92 vs 186.60 ± 21.51, P < 0.001), however, this reduction was not statistically different to 5-FU monotherapy (122.00 ± 5.94 vs 111.00 ± 7.88, P = 0.217; 119.00 ± 17.92 vs 111.00 ± 7.88, P = 0.619, respectively). The levels of COX-1 protein after all treatments were not different from normal rats. A marked increase in the expression of COX-2 protein was observed in the DMH-vehicle group. Over-expression of COX-2 was not significantly decreased by 5-FU treatment alone (95.79 ± 1.60 vs 100 ± 0.00, P = 0.198). However, over-expression of COX-2 was significantly suppressed by CUR (77.52 ± 1.68 vs 100 ± 0.00, P < 0.001), HHC (71.33 ± 3.01 vs 100 ± 0.00, P < 0.001), 5-FU + CUR (76.25 ± 3.32 vs 100 ± 0.00, P < 0.001) and 5-FU + HHC (68.48 ± 2.24 vs 100 ± 0.00, P < 0.001) in the treated groups compared to the vehicle group. Moreover, CUR (77.52 ± 1.68 vs 95.79 ± 1.60, P < 0.001), HHC (71.33 ± 3.01 vs 95.79 ± 1.60, P < 0.001), 5-FU + CUR treatments (76.25 ± 3.32 vs 95.79 ± 1.60, P < 0.001) and 5-FU + HHC (68.48 ± 2.24 vs 95.79 ± 1.60, P < 0.001) markedly decreased COX-2 protein expression more than 5-FU alone. Furthermore, the AI in all treated groups, 5-FU (38.86 ± 4.73 vs 23.56 ± 2.12, P = 0.038), CUR (41.78 ± 6.92 vs 23.56 ± 2.12, P < 0.001), HHC (41.06 ± 4.81 vs 23.56 ± 2.12, P < 0.001), 5-FU + CUR (49.05 ± 6.75 vs 23.56 ± 2.12, P < 0.001) and 5-FU + HHC (53.69 ± 8.59 vs 23.56 ± 2.12, P < 0.001) significantly increased when compared to the DMH-vehicle group. However, the AI in the combination treatments, 5-FU + CUR (49.05 ± 6.75 vs 41.78 ± 6.92, P = 0.192; 49.05 ± 6.75 vs 38.86 ± 4.73, P = 0.771) and 5-FU + HHC (53.69 ± 8.59 vs 41.06 ± 4.81, P = 0.379; 53.69 ± 8.59 vs 38.86 ± 4.73, P = 0.245) did not reach significant levels as compared with each treatment alone and 5-FU monotherapy, respectively., Conclusion: The combined effects of HHC with 5-FU exhibit a synergistic inhibition by decreasing ACF formation mediated by down-regulation of COX-2 expression.

Aim: To investigate the ability of hexahydrocurcumin (HHC) to enhance 5-fluorouracil (5-FU) in inhibiting the growth of HT-29 cells by focusing on cyclooxygenase (COX)-2 expression., Methods: Antiproliferative effects of HHC and 5-FU, alone and in combination, on growth of HT-29 human colon cancer cells were assessed using 5-diphenyltetrazolium bromide (MTT) reduction assay. In combination treatment, low doses of 5-FU were used combined with various concentrations of HHC to minimize the toxicity and side effects of 5-FU. The therapeutic effects of these drugs on down-regulation of COX-2 mRNA and protein expression were examined using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting analysis., Results: MTT reduction assay indicated that HHC alone markedly decreased the viability of HT-29 human colon cancer cells compared to control. Semi-quantitative RT-PCR analysis indicated that HHC is a selective COX-2 inhibitor. This finding was supported by the observation that HHC significantly down-regulates COX-2 mRNA expression compared to the control (control: 100.05% ± 0.03% vs HHC: 61.01% ± 0.35%, P < 0.05) but does not alter COX-1 mRNA. In combined treatment, addition of HHC to a low dose of 5-FU exerts a synergistic effect against the growth of HT-29 cells by markedly reducing cell viability to a greater degree than monotherapy. Semi-quantitative RT-PCR indicated that 5-FU at the concentration of 5 μmol/L in combination with HHC at the concentration of 25 μmol/L significantly down-regulates COX-2 mRNA expression when compared with values in cells treated with 5-FU or HHC alone (HHC + 5-FU: 31.93% ± 5.69%, 5-FU: 100.66% ± 4.52% vs HHC: 61.01% ± 0.35%, P < 0.05)., Conclusion: HHC together with 5-FU exerts a synergistic effect and may prove chemotherapeutically useful in treating human colon cancer.