HLE‐B3 cell line, a human lens epithelial cell line, was used to examine the anti‐glycative and anti‐oxidative protection of aqueous extract prepared from steamed red amaranth leaves against high ...glucose induced injury. Phytochemical profile of this aqueous extract was analyzed. HLE‐B3 cells were pretreated by this aqueous extract at 0.25%, 0.5%, or 1%, and followed by high glucose treatment. Results showed that the content of phenolic acids, flavonoids, anthocyanins, carotenoids, and triterpenoids in this aqueous extract was in the range of 1,107–2,861 mg/100 g dry weight. High glucose decreased cells viability and suppressed Bcl‐2 mRNA expression. This aqueous extract pretreatments raised 11–42% cell survival and upregulated 20–47% Bcl‐2 mRNA expression. High glucose reduced Na+‐K+ ATPase activity and mitochondrial membrane potential (MMP). This aqueous extract raised 27–40% Na+‐K+ ATPase activity, and 18–51% MMP. High glucose stimulated the generation of total advanced glycative endproducts (AGEs), methylglyoxal, and reactive oxygen species (ROS). This aqueous extract pretreatments lowered total AGEs, methylglyoxal, and ROS levels in the range of 0.38–1.17 folds, 1.7–4.9 nmol/mg protein, and 0.35–1.06 relative fluorescence unit/mg protein. High glucose upregulated mRNA expression of aldose reductase, nuclear factor kappa B, and p38. This aqueous extract pretreatments decreased mRNA expression of these factors in the range of 75–159%, 57–151%, and 54–166%. High glucose downregulated mRNA expression of nuclear factor E2‐related factor 2 (Nrf2). This aqueous extract pretreatments increased 12–38% Nrf2 mRNA expression. These results suggested that this aqueous extract might be a potent nutritional supplement to prevent diabetic retinopathy.
Protective effects of caffeic acid (CA) and ellagic acid (EA) in kidney of diabetic mice were examined. CA or EA at 2.5 and 5% was mixed in diet and supplied to diabetic mice for 12 wk. Results ...showed that the intake of CA or EA increased renal content of these compounds, alleviated body weight loss, decreased urine output, increased plasma insulin and decreased blood glucose levels at weeks 6 and 12 (p<0.05). The intake of these compounds dose dependently reduced plasma blood urea nitrogen and elevated creatinine clearance (p<0.05). CA or EA at 5% significantly decreased the levels of plasma HbA1c, urinary glycated albumin, renal carboxymethyllysine, pentosidine, sorbitol and fructose (p<0.05), and significantly diminished renal activity of aldose reductase and sorbitol dehydrogenase, as well as suppressed renal aldose reductase mRNA expression (p<0.05). CA or EA dose dependently lowered renal levels of IL-6, IL-1β, tumor necrosis factor (TNF)-α and monocyte chemoattractant protein 1 (MCP-1) (p<0.05). Furthermore, CA or EA dose dependently down-regulated tumor necrosis factor-α and monocyte chemoattractant protein-1 mRNA expression in kidney (p<0.05). Based on the observed anti-glycative and anti-inflammatory effects, the supplement of CA or EA might be helpful for the prevention or attenuation of diabetic kidney diseases.
This study analyzed the content of eight triterpenes (oleanolic acid, ursolic acid, arjunolic acid, asiatic acid, boswellic acid, corosolic acid, madecassic acid, and maslinic acid) in ten vegetables ...and eight fruits. These compounds at 0.5% were supplied to mice for 4 or 8 weeks. The bioavailability, tissue distribution, and antioxidative protection of these triterpenes were examined. Results showed that triterpenes were detected in eight vegetables and six fruits. Basil and brown mustard contained seven test triterpenes, in the range of 14–102 mg/100 g dry weight. The level of each triterpene in plasma, brain, heart, liver, kidney, colon, and bladder increased as the feeding period was increased from 4 weeks to 8 weeks (P < 0.05). Renal homogenates from mice with triterpene intake had greater antioxidative effects against glucose-induced glutathione loss and malondialdehyde and oxidized glutathione production when compared with those from control groups (P < 0.05). These data support that these triterpenes were absorbed and deposited in their intact forms, which in turn exerted in vivo antioxidative protection.
The effects of Gynura bicolor aqueous extract (GAE) upon glycemic control, coagulation disorder, lipid accumulation, and glycative, oxidative, and inflammatory stresses in diabetic mice were ...investigated. Mice were treated with streptozotocin to induce type 1 diabetes. Diabetic mice were divided into four groups, consumed GAE at 0%, 0.25%, 0.5%, or 1%. Normal group consumed standard mouse basal diet. After 8‐week treatments, mice were sacrificed after overnight fasting. Results showed that GAE supplement at 0.5% and 1% decreased plasma glucose level and increased plasma insulin level. Diabetes lowered plasma level of protein C and anti‐thrombin III; and raised plasminogen activator inhibitor‐1 activity and fibrinogen level in plasma. GAE supplement at 0.5% and 1% reversed these alterations. Histological data, assayed by Oil Red O stain, indicated that GAE supplement decreased lipid accumulation in liver. GAE supplement at 0.5% and 1% reduced aldose reductase activity in heart and kidney; and lowered the levels of carboxymethyllysine and pentosidine in plasma and two organs. Diabetes decreased glutathione content, and increased reactive oxygen species, interleukin (IL)‐1β, IL‐6, and tumor necrosis factor‐α production in heart and kidney. GAE supplement at three test doses reversed these changes. Diabetes upregulated the mRNA expression of p38 and nuclear factor kappa (NF‐κ)B in heart and kidney. GAE supplement suppressed the mRNA expression of both p38 and NF‐κB. These novel findings suggest that Gynura bicolor is a potent functional food for diabetic prevention or alleviation.
•Effects of asiatic acid (AA) or maslinic acid (MA) against kainic acid induced seizure were examined.•AA and MA attenuated inflammatory, oxidative and apoptotic injury in hippocampus.•AA and MA ...altered glutamate and glutamine levels, and glutamine synthetase activity.•AA and MA reduced Ca2+ release in nerve growth factor-differentiated PC12 cells.•Asiatic acid and maslinic acid are potent nutraceutical agents for seizure alleviation.
Seizure is a neurological disorder including hippocampal oxidative and inflammatory stress, and glutamate toxicity. Thus, any agent(s) that mitigate(s) these events in hippocampus might attenuate seizure severity. The effects of asiatic acid (AA) or maslinic acid (MA) pre-administration at 20 or 40mg/kg body weight/day upon inflammatory, oxidative and apoptotic injury in hippocampus of kainic acid (KA)-treated mice were examined. KA induced seizure-like behavioral patterns, which was attenuated by AA or MA pre-administration. KA stimulated the release of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha and prostaglandin E2 in hippocampus of mice. AA or MA pre-administration decreased the production of these inflammatory factors. AA or MA also diminished KA-induced increase in hippocampal cyclooxygenase-2 activity and relative NF-κB p50/65 binding activity. KA depleted glutathione content and promoted reactive oxygen species generation. AA or MA pre-administration reversed these alterations. KA lowered Bcl-2 mRNA expression and increased Bax mRNA expression. AA or MA treatments reduced Bax mRNA expression. AA or MA pre-administration enhanced glutamine synthetase activity, decreased glutamate level and increased glutamine level in hippocampus of KA treated mice. In addition, AA or MA pre-treatments at 10 and 20μM increased viability and decreased plasma membrane damage in KA treated nerve growth factor (NGF)-differentiated PC12 cells. Both agents also lowered the release of calcium ion induced by KA in NGF-treated PC12 cells. These findings support that asiatic acid and maslinic acid are potent nutraceutical agents for seizure alleviation.
The content of several phenolic acids and flavonoids in aqueous extract (AE) and ethanol extract (EE) of daylily flower (Hemerocallis fulva L.) was analyzed. The effects of AE or EE at 0.5%, 1%, or ...2% in HUVE cells against high glucose‐induced cell death, oxidative, and inflammatory damage were examined. Results showed that seven phenolic acids and seven flavonoids could be detected in AE or EE, in the range of 29 to 205 and 41 to 273 mg/100 g, respectively. Compared with the control groups, high glucose raised the activity of caspase‐3 and caspase‐8; suppressed Bcl‐2 mRNA expression and increased Bax mRNA expression; and induced HUVE cells apoptosis. The pretreatments from AE or EE at 1% or 2% reduced caspase‐3 activity and Bax mRNA expression, and enhanced cell viability. High glucose decreased glutathione content; stimulated the production of reactive oxygen species, interleukin‐6, tumor necrosis factor‐alpha, and prostaglandin E2; raised the activity of cyclooxygenase‐2 and nuclear factor kappa B p50/65 binding; and reduced the activity of glutathione peroxidase, glutathione reductase, and catalase in HUVE cells. AE pretreatments at 1% and 2% reversed these changes. These novel findings suggested that daylily flower was rich in phytochemicals, and could be viewed as a potent functional food against diabetes.
The effects of histidine, alanine and carnosine on activity and/or mRNA expression of lipogenic enzymes and sterol regulatory element-binding proteins (SREBPs) in liver and adipose tissue from high ...fat diet treated mice were examined. Histidine, alanine or carnosine, each agent at 1g/l was added into drinking water for 8-wk supplement. Histidine or carnosine supplement increased hepatic levels of alanine, histidine and carnosine. High fat diet evoked lipogenesis via raising the activity and mRNA expression of glucose-6-phosphate dehydrogenase, malic enzyme, fatty acid synthase (FAS), 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, SREBP-1a, -1c and -2 in liver and adipose tissue (P<0.05), which consequently increased mice body weight, epididymal fat, and hepatic triglyceride and cholesterol contents (P<0.05). The intake of histidine or carnosine significantly diminished the activity and mRNA expression of malic enzyme, FAS, HMG-CoA reductase, SREBP-1c and SREBP-2, which led to lower body weight, epididymal fat, and hepatic triglyceride and cholesterol levels (P<0.05). Mice consumed high fat diet exhibited hyper-insulinemia, hyper-leptinemia, hypo-adiponectinemia and hypo-ghrelinemia. Histidine or carnosine treatments significantly improved insulin sensitivity and attenuated hyper-insulinemia (P<0.05). These results support that histidine and carnosine are effective agents for mitigating high fat diet induced hepatic steatosis.
Nerve growth factor differentiated PC12 cells were used to examine the antioxidative and anti-inflammatory effects of astaxanthin (AX) and canthaxanthin (CX). PC12 cells were pretreated with AX or CX ...at 10 or 20 μM, and followed by exposure of hydrogen peroxide (H₂O₂) or 1-methyl-4-phenylpyridinium ion (MPP⁺) to induce cell injury. H₂O₂ or MPP⁺ treatment significantly decreased cell viability, increased lactate dehydrogenase (LDH) release, enhanced DNA fragmentation, and lowered mitochondrial membrane potential (MMP) (P < 0.05). The pretreatments from AX or CX concentration-dependently alleviated H₂O₂ or MPP⁺-induced cell death, LDH release, DNA fragmentation, and MMP reduction (P < 0.05). Either H₂O₂ or MPP⁺ treatment significantly increased malonyldialdehyde (MDA) and reactive oxygen species (ROS) formations, decreased glutathione content, and lowered glutathione peroxidase (GPX) and catalase activities (P < 0.05). The pretreatments from AX or CX significantly retained GPX and catalase activities, and decreased MDA and ROS formations (P < 0.05). H₂O₂ or MPP⁺ treatment significantly decreased Na⁺-K⁺-ATPase activity, elevated caspase-3 activity and levels of interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α (P < 0.05); and the pretreatments from these agents significantly restored Na⁺-K⁺-ATPase activity, suppressed caspase-3 activity and release of IL-1, IL-6, and TNF-α (P < 0.05). Based on the observed antioxidative and anti-inflammatory protection from AX and CX, these 2 compounds were potent agents against neurodegenerative disorder.
Renal protection from
s
-ethyl cysteine (SEC) against cisplatin (CP)-induced inflammatory and oxidative injury was examined. Mice were divided into five groups: normal group, 0.25% SEC group, CP ...group, 0.125% SEC + CP group, 0.25% SEC + CP group. After 2 weeks supplementation, mice of CP and SEC + CP groups received CP treatment. H&E stain showed that CP caused infiltration of inflammatory cells and necrosis of tubular cells. SEC pre-treatments attenuated CP-induced inflammatory injury and degeneration. SEC pre-treatments limited CP-stimulated release of interleukin (IL)-1beta, IL-6, tumor necrosis factor-alpha and prostaglandin E
2
in kidney. CP raised the renal activity and mRNA expression of cyclooxygenase-2 and nuclear factor kappa B. SEC pre-treatments reversed these alterations. CP increased the production of reactive oxygen species and nitric oxide, and lowered glutathione content, glutathione peroxidase and glutathione reductase activities in kidney. SEC pre-treatments reversed these changes. CP up-regulated renal inducible nitric oxide synthase (iNOS) mRNA expression, and down-regulated nuclear factor E2-related factor (Nrf)-2 and heme oxygenase (HO)-1 mRNA expression. SEC pre-treatments suppressed iNOS mRNA expression; and enhanced renal Nrf2 and HO-1 mRNA expression. These novel findings suggest that dietary SEC via exerting its multiple bio-functions could be considered as a protective agent for kidney against CP.
Gynura bicolor leaf aqueous extract (GAE) is rich in phytochemicals including phenolic acids, flavonoids, carotenoids, and anthocyanins. Effects of GAE upon hepatic injury in mice with chronic ...ethanol intake were examined. Lieber–DeCarli liquid diet with ethanol was used to induce hepatic lipid accumulation, oxidative, glycative, and inflammatory injury. GAE at 0.25% or 0.5% was added in feeds, and supplied to mice consumed Lieber–DeCarli liquid diet with ethanol for 6 wk. Blood and liver were collected for analyses. Results showed that ethanol increased plasma and hepatic triglyceride and cholesterol content, and affected plasma levels of insulin, adiponectin, leptin, and ghrelin. GAE at both doses decreased lipid accumulation, and at high dose improved hormones abnormality. Histological data revealed that GAE supplement mitigated hepatic lipid deposit. Ethanol increased plasma Nε‐(carboxyethymethyl)‐lysine and pentosidine levels. GAE at high doses lowered those glycative factors. Ethanol depleted glutathione content, increased CYP2E1 activity and reactive oxygen species production, and reduced the activity of glutathione peroxide, glutathione reductase and catalase in liver. GAE supplement at both doses reversed these alterations and attenuated hepatic oxidative stress. GAE supplement also at both doses decreased hepatic inflammatory cytokines release in ethanol treated mice. These findings support that leaves of G. bicolor is a functional food with liver protective activities against ethanol.
