Phytochemical Constituents, Folk Medicinal Uses, and Biological Activities of Genus Angelica: A Review

Genus Angelica is one of the widely distributed and well-known genera of family Umbelliferae. It is utilized mainly by Chinese and Korean populations especially in their folk medicine. Angelica comprises a lot of medicinally important phytoconstituents such as coumarins, furanocoumarins, flavonoids, essential oils, verbascosides, polysaccharides, etc. Members of this genus play important roles, namely antioxidant, anti-inflammatory, anti-microbial, anti-diabetic, skin-whitening, cytotoxic, hepatoprotective, and many others. This review draws attention to many species of genus Angelica with much focus on A. dahurica being one of the highly medicinally used species within this genus.

From the gut to the heart: L. plantarum and inulin administration as a novel approach to control cardiac apoptosis via 5-HT2B and TrkB receptors in diabetes

BACKGROUND & AIMS

Type 2 diabetes mellitus, as a metabolic disorder, can lead to diabetic cardiomyopathy, identified by cardiomyocyte apoptosis and myocardial fibrosis. Brain-derived neurotrophic factor (BDNF) and serotonin are two neurotransmitters that can control cardiomyocyte apoptosis and myocardial fibrosis through their cardiac receptors. In the present study, we investigated the impacts of L. plantarum and inulin supplementation on the inhibition of cardiac apoptosis and fibrosis by modulating intestinal, serum, and cardiac levels of serotonin and BDNF as well as their cardiac receptors.

METHODS

Diabetes was induced by a high-fat diet and streptozotocin in male Wistar rats. Rats were divided into six groups and were supplemented with L. plantarum, inulin or their combination for 8 weeks. Finally, the rats were killed and levels of intestinal, serum, and cardiac parameters were evaluated.

RESULTS

Concurrent administration of L. plantarum and inulin caused a significant rise in the expression of cardiac serotonin and BDNF receptors (P < 0.001) as well as a significant fall in cardiac interstitial and perivascular fibrosis (P < 0.001, both) and apoptosis (P = 0.01). Moreover, there was a strong correlation of cardiac 5-Hydroxytryptamine 2B (5-HT2B) and tropomyosin receptor kinase B (TrkB) receptors with interstitial/perivascular fibrosis and apoptosis (P < 0.001, both).

CONCLUSIONS/INTERPRETATION

Results revealed beneficial effects of L. plantarum, inulin or their combination on intestinal, serum, and cardiac serotonin and BDNF accompanied by higher expression of their cardiac receptors and lower levels of cardiac apoptotic and fibrotic markers. It seems that L. plantarum and inulin supplementation could be considered as a novel adjunct therapy to reduce cardiac complications of type 2 diabetes mellitus.

Integrating Chinese and Western medicines reduced the incidence of hepatocellular carcinoma in patients with diabetes mellitus: A Taiwanese population-based cohort study

OBJECTIVES

Much epidemiological evidence links diabetes mellitus (DM) to the development of multiple cancers and, in particular, the development of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether Chinese herbal medicine (CHM) reduces the incidence of HCC in patients receiving Western antidiabetic drugs.

INTERVENTIONS AND MAIN OUTCOME MEASURES

This retrospective cohort study used data from the National Health Insurance Research Database involving 81,105 diabetic patients, including 5122 CHM users and 25,966 non-CHM users. Analyses of treatment effects were adjusted for covariates including gender, age, comorbidities, antidiabetic drugs and liver medications. NodeXL software performed a network analysis to identify the 50 most commonly used CHM herbs and formulas.

RESULTS

In Cox proportional hazards models adjusted for demographic and clinical characteristics, DM patients exposed to adjuvant CHM therapy were significantly less likely to develop HCC compared with non-CHM users (adjusted hazard ratio [aHR] 0.59; 95 % confidence interval [CI], 0.41-0.87; p = 0.01). Kaplan-Meier analysis revealed a lower 10-year cumulative risk of HCC among CHM users compared with non-CHM users. Amongst the 10 individual CHM herbs and herbal formulas most commonly prescribed for DM, the most frequent were Salvia miltiorrhiza (Dan Shen) and Liu Wei Di Huang Wan, respectively.

CONCLUSION

This nationwide retrospective cohort study from Taiwan provides some valuable insights into the prescribing characteristics of CHM treatment in patients with DM. Compared with use of Western antidiabetic medications alone, use of adjuvant CHM effectively reduces the incidence of HCC in patients with DM.

Ameliorative effects of taurine against diabetes: a review

Diets in rats and humans have shown promising results. Taurine improved glucagon activity, promoted glycemic stability, modified glucose levels, successfully addressed hyperglycemia via advanced glycation end-product control, improved insulin secretion and had a beneficial effect on insulin resistance. Taurine treatment performed well against oxidative stress in brain, increased the secretion of required hormones and protected against neuropathy, retinopathy and nephropathy in diabetes compared with the control. Taurine has been observed to be effective in treatments against diabetic hepatotoxicity, vascular problems and heart injury in diabetes. Taurine was shown to be effective against oxidative stress. The mechanism of action of taurine cannot be explained by one pathway, as it has many effects. Several of the pathways are the advanced glycation end-product pathway, PI3-kinase/AKT pathway and mitochondrial apoptosis pathway. The worldwide threat of diabetes underscores the urgent need for novel therapeutic measures against this disorder. Taurine (2-aminoethane sulfonic acid) is a natural compound that has been studied in diabetes and diabetes-induced complications.

Effects of quercetin on the expression of MCP-1, MMP-9 and VEGF in rats with diabetic retinopathy

Diabetic retinopathy, a severe complication of diabetes, is the leading cause of blindness in the developed world. This study investigated the effects of quercetin on levels of monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9) and vascular endothelial growth factor (VEGF) in serum of rats with diabetic retinopathy, and explored the functional mechanisms of quercetin in the treatment of diabetic retinopathy. Twenty rats with induced diabetes were divided into a model group and a quercetin group, with 10 rats in each group. Ten healthy rats were also included to serve as a control group. Rats in the quercetin group were treated with an intragastric injection of quercetin (150 mg/kg), while the same amount of sodium carboxymethyl cellulose (CMCNa) was used for rats in the model group and the control group. The treatment was performed once per day and blood glucose was measured in each group at 0, 10 and 20 weeks after the first treatment. Blood glucose tests showed that quercetin did not reduce blood glucose in rats with diabetes. However, pathological examination showed that quercetin could relieve pathological changes caused by diabetes, such as retinal edema and vacuoles. ELISA results showed that, compared with the control group, levels of MCP-1, MMP-9 and VEGF in the model group were significantly increased (P<0.01). No significant difference in serum MCP-1 content was found between the model group and the quercetin group, but levels of MMP-9 and VEGF were significantly decreased in the quercetin group (P<0.01). Results of RT-PCR and western blot analysis showed that, compared with the control group, levels of MCP-1, MMP-9 and VEGF mRNA and protein in the retinal tissue of rats in the model group were significantly increased (P<0.01). No significant differences in expression levels of MCP-1 mRNA and protein were found between the model group and the quercetin group, but levels of MMP-9 and VEGF mRNA and protein were significantly decreased in the quercetin group (P<0.01). Quercetin has a certain therapeutic effect on rats with diabetic retinopathy and its effect may be achieved by reducing the expression of MMP-9 and VEGF, but not the inflammatory mediator, MCP-1.

Hydroethanolic extract of Smallanthus sonchifolius leaves improves hyperglycemia of streptozotocin induced neonatal diabetic rats

OBJECTIVE

To evaluate the effect of hydroethanolic extract of yacon on the hyperglycemia induced by streptozotocin (STZ) in neonatal rats.

METHODS

Wistar rats aged two days old received an intraperitoneal injection of STZ (160 mg/kg); after seven weeks, glycosuria was determined and animals with glucose levels above 250 mg/dL were included in the study. Groups of diabetic and non-diabetic rats were treated orally with yacon extract at a dose of 400 mg/kg/d for 14 d. Tests were made for phytochemical characterization, glucose tolerance and toxicity.

RESULTS

The results showed that treatment with the extract reduced the glucose levels of fed diabetic rats and did not change the glucose levels of fasting diabetic and normal rats. Additionally, also it was observed that treatment with the extract reduced blood glucose levels of diabetic rats during the oral and intravenous glucose tolerance tests. There was no change in body weight, liver enzymes or mortality with yacon extract treatment. The phytochemical screening revealed the presence of caffeic acid, chlorogenic acid, ferulic acid and gallic acid.

CONCLUSIONS

The data suggest that yacon extract reduces hyperglycemia, possibly by improving insulin sensibility through its phytochemicals constituents (phenolic compounds).

Yiqi Huaju formula, a Chinese herbal medicine, reduces arterial pressure in salt‑sensitive hypertension by inhibiting renin‑angiotensin system activation

Hypertension is a chronic disease with a high prevalence, and is associated with a high risk of vascular disease and premature death. Traditional Chinese medicine has been administered to treat hypertension for many years. In the present study, the effects of Yiqi Huaju formula (YQ; a compound used in traditional Chinese herbal medicine) were observed in salt‑sensitive hypertension, which was induced by a high‑salt and high‑fat (HSF) diet and the potential mechanism was investigated. YQ was prepared from five plant extracts and was dissolved in normal sodium chloride prior to use. Male Sprague‑Dawley rats were randomly divided into three groups, and fed either a normal diet (control), an HSF diet or an HSF diet with YQ. At week eight, blood pressure was measured and 24‑h urine samples were collected from all of the rats. The rats were subsequently sacrificed, and their blood was collected for biochemical analyses and kidney tissue samples were dissected for the immunohistochemical assay. YQ was observed to decrease the high arterial pressure and serum total cholesterol level, which had been induced by the HSF diet. It also enhanced the excretion of urinary angiotensinogen, Na+, and decreased the loss of urinary aldosterone, K+ and microalbuminuria. In addition, YQ inhibited the high mRNA expression level of renal renin, angiotensin II (Ang II), and Ang II receptor, type 1 (AT1R), and inhibited the protein expression of renal AT1R and Ang II receptor type 2, which had been induced by the HSF diet. These results indicate that YQ may reduce the arterial pressure in salt‑sensitive hypertension via the inhibition of renin‑angiotensin system activation.

Protective effect of arjunolic acid against atorvastatin induced hepatic and renal pathophysiology via MAPK, mitochondria and ER dependent pathways

3-Hydroxy-3-methylglutaryl-CoA reductase inhibitor, atorvastatin (ATO), is a highly effective drug used for the treatment of hypercholesterolemia and hypertriglyceridemia. Its application is restricted now-a-days due to several acute and chronic side effects. ATO induced anti hypercholesterolemia and hepatic tissue toxicity has been reported to follow different mechanisms. The present study has been carried out to investigate the protective role of arjunolic acid (AA) against ATO induced oxidative impairment and cell death in hepatic and renal tissue in mice. Administration of ATO (at a dose 30 mg/kg/day for 8 weeks) enhanced serum markers, increased reactive oxygen species (ROS) production and altered the pro oxidant-antioxidant status of liver and kidney tissues. Our experimental evidence suggests that ATO exposure induces apoptotic cell deathby the activation of caspase-3 and reciprocal regulation of Bcl-2/Bax with the concomitant reduction of mitochondrial membrane potential and increased level of cytosolic cytochrome c, Apaf1, caspase-9. Besides, ATO markedly increased the phosphorylation of MAPKs, enhanced caspase-12 and calpain level. Histological studies and DNA fragmentation analysis also support the toxic effect of ATO in these organs pathophysiology. Post treatment with AA (at a dose of 20 mg/kg body weight for 4 days), however, reduced ATO-induced oxidative stress and suppressed all these apoptotic events. Results suggest that AA could effectively and extensively counteract these adverse effects and might protect liver and kidney from ATO-induced severe tissue toxicity.

Evaluation of neonatal streptozotocin induced diabetic rat model for the development of cataract

Type 2 diabetes (T2D) generally follows prediabetes (PD) conditions such as impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT). Although studies reported an association of IGT or IFG with cataract, the experimental basis for PD associated cataract is not known. Hence, we evaluated neonatal streptozotocin (nSTZ) induced rat model to study PD associated cataractogenesis by injecting STZ to two-day old rats. While majority (70%) of nSTZ injected pups developed IGT (nSTZ-PD) by two months but not cataract even after seven months, remaining (30%) nSTZ rats developed hyperglycemia (nSTZ-D) by two months and mature cataract by seven months. Lens biochemical analysis indicated increased oxidative stress as indicated by increased SOD activity, lipid peroxidation, and protein carbonyl levels in nSTZ-D cataractous lens. There was also increased polyol pathway as assessed by aldose reductase activity and sorbitol levels. Though nSTZ-PD animals have not shown any signs of lenticular opacity, insolubilization of proteins along with enhanced polyol pathway was observed in the lens. Further there was increased oxidative stress in lens of IGT animals. These results suggest that oxidative stress along with increased polyol pathway might play a role in IGT-associated lens abnormalities. In conclusion, nSTZ-PD rat model could aid to investigate IGT-associated lens abnormalities.

Antihyperglycemic and antioxidant activity of Clitorea ternatea Linn. on streptozotocin-induced diabetic rats

Ethanol extract of Clitorea ternatea Linn. (EECT) was evaluated for its antihyperglycemic and antioxidative activity in normal and streptozotocin-induced diabetic rats. Antihyperglycemic activity of EECT was studied in normal fasted and glucose fed hyperglycemic and epinephrine induced hyperglycemic rats by estimating fasting serum glucose (FSG) by glucose oxidisae or peroxidase enzymatic method. Antioxidant activity of EECT was studied by assaying lipid peroxide/Thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), total nitric oxide, catalase (CAT) and glutathione levels in diabetic rats. The EECT (200 and 400 mg/kg) showed significant antihyperglycemic activity by decreasing FSG in all hyperglycemic models except epinephrine induced hyperglycemic rats; in which improvement in FSG was observed only with EECT in 400 mg/kg dose, whereas significant decrease in TBARS (P < 0.001), nitric oxide (P < 0.001) and significant increase in SOD (P < 0.001), CAT (P < 0.01) and reduced glutathione levels (P < 0.001) was observed in animals treated with EECT (200 and 400 mg/kg) compared to diabetic control group. The results indicated that EECT has remedial effects on hyperglycemia and oxidative stress in diabetic rats.

An update on oxidative stress-mediated organ pathophysiology

Exposure to environmental pollutants and drugs can result in pathophysiological situations in the body. Research in this area is essential as the knowledge on cellular survival and death would help in designing effective therapeutic strategies that are needed for the maintenance of the normal physiological functions of the body. In this regard, naturally occurring bio-molecules can be considered as potential therapeutic targets as they are normally available in commonly consumed foodstuffs and are thought to have minimum side effects. This review article describes the detailed mechanisms of oxidative stress-mediated organ pathophysiology and the ultimate fate of the cells either to survive or to undergo necrotic or apoptotic death. The mechanisms underlying the beneficial role of a number of naturally occurring bioactive molecules in oxidative stress-mediated organ pathophysiology have also been included in the review. The review provides useful information about the recent progress in understanding the mechanism(s) of various types of organ pathophysiology, the complex cross-talk between these pathways, as well as their modulation in stressed conditions. Additionally, it suggests possible therapeutic applications of a number of naturally occurring bioactive molecules in conditions involving oxidative stress.

Protective role of D-saccharic acid-1,4-lactone in alloxan induced oxidative stress in the spleen tissue of diabetic rats is mediated by suppressing mitochondria dependent apoptotic pathway

The present study investigated the role of D-saccharic acid 1,4-lactone (DSL) in the spleen tissue of alloxan (ALX) induced diabetic rats. Diabetes was induced in rats by injecting ALX (at a dose of 120 mg/kg body weight) intraperitoneally in sterile normal saline. Elevated levels of blood glucose, glycosylated Hb and TNFα decreased levels of plasma insulin and disturbed intra-cellular antioxidant machineries were detected in ALX exposed animals. Oral administration of DSL at a dose of 80 mg/kg body weight, however, restored these alterations in diabetic rats. Studies on the mechanism of ALX-induced diabetes showed that hyperglycemia caused disruption of mitochondrial membrane potential in the spleen, released cytochrome C in the cytosol, activated caspase 3 and ultimately led to apoptotic cell death. Results suggest that DSL possesses the ability of protecting the spleen tissue from ALX-induced hyperglycemia and thus could act as an anti-diabetic agent in lessening diabetes associated spleen dysfunction.

Hypoglycemic effect of Rehmannie Radix Preparata (Sookjihwang) extract in streptozotocin-induced diabetic rats

Rhemannie Radix Preparata (RRP) has been previously employed in traditional oriental medicine as a treatment for diabetic thirst and improving blood flow. The aim of this study was to evaluate its hypoglycemic control by assaying the activities of key enzymes of carbohydrate metabolism in streptozotocin-(STZ)-induced diabetic rats. Further, RRP extracts were prepared in water (RRPW), in 50% ethanol (RRP50), and in 100% ethanol (RRP100), respectively, and compared for their actions in diabetic rats. The oral treatment of RRP (5 mg/kg b.w./d) to diabetic rats for 21 days resulted in a significant decline in blood glucose by 67% compared to diabetic control rats (P < 0.05). The altered activities of glucokinase, glucose-6-phosphate dehydrogenase (G6PD), 6-phosphogluconate dehydrogenase (6PGD), and acetyl CoA carboxylase (ACC) in the livers of diabetic rats were reversed significantly to near-normal levels by the administration of RRP (P < 0.05). Among the three RRP extracts, RRP100 was the most effective in terms of hypoglycemic action. However, the administration of RRP to diabetic rats did not improve insulin production. The modulatory effects of RRP100 on the attenuation of carbohydrate enzyme activities appear to hold promise for widespread use for the treatment of diabetes in the future.

Streptozotocin induced activation of oxidative stress responsive splenic cell signaling pathways: protective role of arjunolic acid

Present study investigates the beneficial role of arjunolic acid (AA) against the alteration in the cytokine levels and simultaneous activation of oxidative stress responsive signaling pathways in spleen under hyperglycemic condition. Diabetes was induced by injection of streptozotocin (STZ) (at a dose of 70 mg/kg body weight, injected in the tail vain). STZ administration elevated the levels of IL-2 as well as IFN-gamma and attenuated the level of TNF-alpha in the sera of diabetic animals. In addition, hyperglycemia is also associated with the increased production of intracellular reactive intermediates resulting with the elevation in lipid peroxidation, protein carbonylation and reduction in intracellular antioxidant defense. Investigating the oxidative stress responsive cell signaling pathways, increased expressions (immunoreactive concentrations) of phosphorylated p65 as well as its inhibitor protein phospho IkappaBalpha and phosphorylated mitogen activated protein kinases (MAPKs) have been observed in diabetic spleen tissue. Studies on isolated splenocytes revealed that hyperglycemia caused disruption of mitochondrial membrane potential, elevation in the concentration of cytosolic cytochrome c as well as activation of caspase 3 leading to apoptotic cell death. Histological examination revealed that diabetic induction depleted the white pulp scoring which is in agreement with the reduced immunological response. Treatment with AA prevented the hyperglycemia and its associated pathogenesis in spleen tissue. Results suggest that AA might act as an anti-diabetic and immunomodulatory agent against hyperglycemia.