Effect of dragon fruit extract on oxidative stress and aortic stiffness in streptozotocin-induced diabetes in rats

Neuroprotective effect of red dragon fruit extract ameliorates oxidative stress and inflammation in D-galactose-induced aging rat model: biochemical, histological and immunohistochemical study

Aging is a worldwide socioeconomic burden. Cerebellar aging is an enigma contributing to many behavioral aging disorders, hence is its hindering by prophylactic measurements is a crucial geriatric research target. Red dragon fruit (RDF) is a tropical fruit with antioxidant, anti-inflammatory and anti-apoptotic properties. This study aimed to determine the protective effect of RDF extract against cerebellar aging. Thirty-two male albino rats were randomly allocated into 4 groups: Control, RDF, aged and RDF-aged groups. Aged group revealed structural distortion affecting cerebellar layers including a significant (P < 0.05) decrease in Purkinje cells number and decrease in granular cell layer thickness by comparison to the control and RDF groups. Additionally, distorted capillary endothelium, and defective myelination were noticed. Interestingly, cerebellar active caspase-3, iNOS, MDA and 3-NT and serum TNF-α levels significantly increased with aging by comparison to the control and RDF groups (all P < 0.05). Biochemical analysis revealed a significant (P < 0.05) decrease in cerebellar SOD and serum GSH levels in aged rats. RDF extract remarkably ameliorated most of the neuronal degenerative changes with a significant (P < 0.05) increase in Purkinje cells numbers, and granular cell layer thickness by comparison to the aged group. Furthermore, it resulted in a significant (P < 0.05) decrease in cerebellum expression of active caspase-3, iNOS, MDA, 3-NT, and serum TNF-α levels associated with a significant (P < 0.05) increase in cerebellar SOD and serum GSH levels by comparison to the aged group. To the best of our knowledge this is the first study showing a neuroprotective effect for RDF against cerebellar aging. RDF might be effective in attenuation of age-induced cerebellar degenerative changes through its anti-apoptotic, antioxidant and anti-inflammatory effects.

Plant-Based Diets and Phytochemicals in the Management of Diabetes Mellitus and Prevention of Its Complications: A Review

Diabetes mellitus (DM) is currently regarded as a global public health crisis for which lifelong treatment with conventional drugs presents limitations in terms of side effects, accessibility, and cost. Type 2 diabetes (T2DM), usually associated with obesity, is characterized by elevated blood glucose levels, hyperlipidemia, chronic inflammation, impaired β-cell function, and insulin resistance. If left untreated or when poorly controlled, DM increases the risk of vascular complications such as hypertension, nephropathy, neuropathy, and retinopathy, which can be severely debilitating or life-threatening. Plant-based foods represent a promising natural approach for the management of T2DM due to the vast array of phytochemicals they contain. Numerous epidemiological studies have highlighted the importance of a diet rich in plant-based foods (vegetables, fruits, spices, and condiments) in the prevention and management of DM. Unlike conventional medications, such natural products are widely accessible, affordable, and generally free from adverse effects. Integrating plant-derived foods into the daily diet not only helps control the hyperglycemia observed in DM but also supports weight management in obese individuals and has broad health benefits. In this review, we provide an overview of the pathogenesis and current therapeutic management of DM, with a particular focus on the promising potential of plant-based foods.

HPLC-ESI/MS-MS metabolic profiling of white pitaya fruit and cytotoxic potential against cervical cancer: Comparative studies, synergistic effects, and molecular mechanistic approaches

Natural approach became a high demand for the prevention and treatment of such diseases for their proven safety and efficacy. This study is aimed to perform comparative phytochemical analysis of white pitaya (Hylocereus undatus) peel, pulp and seed extracts via determination of total flavonoid content, phenolic content, and antioxidant capacity, coupled with HPLC-ESI/MS-MS analysis. Further, we evaluated the synergistic cytotoxic potential with Cisplatin against cervical cancer cells with investigation of underlying mechanism. The highest content of phenolics and antioxidants were found in both seed and peel extracts. The HPLC-ESI/MS-MS revealed identification of flavonoids, phenolic acids, anthocyanin glycosides, lignans, stilbenes, and coumarins. The cytotoxicity effects were evaluated by MTT assay against prostate, breast and cervical (HeLa) and Vero cell lines. The seed and peel extracts showed remarkable cytotoxic effect against all tested cell lines. Moreover, the selectivity index confirmed high selectivity of pitaya extracts to cancer cells and safety on normal cells. The combined therapy with Cisplatin effectively enhanced its efficacy and optimized the treatment outcomes, through the apoptotic ability of pitaya extracts in HeLa cells, as evaluated by flow cytometry. Besides, RT-PCR and western blotting analysis showed downregulation of Bcl-2 and overexpression of P53, BAX among HeLa cells treated with pitaya extracts, which eventually activated apoptosis process. Thus, pitaya extract could be used as adjuvant therapy with cisplatin for treatment of cervical cancer. Furthermore, in-vivo extensive studies on the seed and peel extracts, and their compounds are recommended to gain more clarification about the required dose, and side effects.

Interaction between Nuclear Receptor and Alpha-Adrenergic Agonist Subtypes in Metabolism and Systemic Hemodynamics of Spontaneously Hypertensive Rats

Partial and full PPAR-γ agonists have shown promising effects and antihypertensive and antidiabetic agents through increased plasma adiponectin concentration. This study is aimed at examining the role of PPAR-γ, alpha-adrenoceptors, and adiponectin receptors in the modulation of vasopressor responses to angiotensin II (Ang II) and adrenergic agonists, after a subset treatment of partial and full PPAR-γ agonists, each individually, and also when coupled with adiponectin in SHRs. The antioxidant potential and metabolic indices for these animals were also determined. Group I (WKY) and group II (SHR) were designated as normotensive control and hypertensive control, respectively. Groups III (SHR) and IV (SHR) received irbesartan (30 mg/kg) and pioglitazone (10 mg/kg) orally for 28 days, and groups V (SHR), VI (SHR), and VII (SHR) were treated with adiponectin (2.5 μg/kg) intraperitoneally alone, in combination with irbesartan, and in combination with pioglitazone, respectively, from days 21 to 28 only. On day 29, sodium pentobarbitone (60 mg/kg) was used to anesthetize all test animals, and systemic hemodynamic and plasma adiponectin concentrations and in vitro and in vivo antioxidant potential were measured. As compared to the WKY control, the SHR control group's noninvasive blood pressure and basal mean arterial pressure were significantly greater, along with increased arterial stiffness, lower plasma nitric oxide, adiponectin concentration, and antioxidant enzyme levels (all P < 0.05). However, they were gradually normalized by single drug treatments in all groups, and to a greater extent in the SHR + Irb + Adp group (P < 0.05). In the acute study, the dose dependant mean arterial pressure responses to intravenously administered adrenergic agonists and angiotensin-II were significantly larger in SHRs as compared to WKY by 20-25%. Adiponectin alone and in combination significantly blunted vasopressor responses to these alpha-adrenergic agonists in the SHR + Pio + Adp group by 63%, whereas attenuated responses to ANG-II administration to 70% in SHR + Irb + Adp. In conclusion, the combined treatment of adiponectin with PPAR-agonists reduced the systemic vascular responses to adrenergic agonists and improved arterial stiffness. This an evidence of the interaction of adiponectin receptors, PPAR-γ, alpha-adrenoceptors, and ANG-II in the systemic vasculature of SHRs. A significant level of synergism has also been proved among full PPAR-γ agonists and adiponectin receptors.

Pitaya Nutrition, Biology, and Biotechnology: A Review

Pitaya (Hylocereus spp.) is a member of the cactus family that is native to Central and South America but is now cultivated throughout the sub-tropical and tropical regions of the world. It is of great importance due to its nutritional, ornamental, coloring, medicinal, industrial, and high consumption values. In order to effectively utilize and develop the available genetic resources, it is necessary to appreciate and understand studies pertaining to the usage, origin, nutrition, diversity, evaluation, characterization, conservation, taxonomy, and systematics of the genus Hylocereus. Additionally, to gain a basic understanding of the biology of the plant, this review has also discussed how biotechnological tools, such as cell and tissue culture, micropropagation (i.e., somatic embryogenesis, organogenesis, somaclonal variation, mutagenesis, androgenesis, gynogenesis, and altered ploidy), virus-induced gene silencing, and molecular marker technology, have been used to enhance pitaya germplasm.

Anti-Inflammatory, Antioxidant, and Other Health Effects of Dragon Fruit and Potential Delivery Systems for Its Bioactive Compounds

Dragon fruit (Hylocereus genus) has the potential for the prevention of diseases associated with inflammatory and oxidative processes. We aimed to comprehensively review dragon fruit health effects, economic importance, and possible use in delivery systems. Pubmed, Embase, and Google Scholar were searched, and PRISMA (Preferred Reporting Items for a Systematic Review and Meta-Analysis) guidelines were followed. Studies have shown that pitaya can exert several benefits in conditions such as diabetes, dyslipidemia, metabolic syndrome, cardiovascular diseases, and cancer due to the presence of bioactive compounds that may include vitamins, potassium, betacyanin, p-coumaric acid, vanillic acid, and gallic acid. Moreover, pitaya has the potential to be used in food and nutraceutical products as functional ingredients, natural colorants, ecologically correct and active packaging, edible films, preparation of photoprotective products, and additives. Besides the importance of dragon fruit as a source of bioactive compounds, the bioavailability is low. The development of delivery systems such as gold nanoparticles with these compounds can be an alternative to reach target tissues.

The effect of ingestion of red dragon fruit extract on levels of malondialdehyde and superoxide dismutase after strenuous exercise in rats (Rattus norvegicus)

Background: Prolonged activation of skeletal muscles causes a decrease in the production of fatigue. Exercise with strenuous intensity causes an increase in Reactive Oxygen Species (ROS). An increase in free radicals causes oxidative stress resulting in damage to cell function to mitochondrial dysfunction, and fatigue. This study aimed to determine the antioxidant potential of red dragon fruit (RDF) to delay fatigue due to oxidative stress, which improves cell function in mitochondria.

Methods: 25 male rats (Rattus norvegicus) aged three months were divided into five groups: Group K1 was N.A. (No Activity) but drinking and eating; Group K2 performed strenuous exercise without RDF treatment; Groups 3, 4, and 5 (P1, P2 and P3, respectively) performed strenuous exercise and were treated with 75 mg kg ^-1.bw, 150 mg kg ^-1.bw, and 300 mg kg ^-1.bw of RDF extract, respectively. The exercise for the rats involved intense swimming for 20 minutes  a day three time a week for fouweeks.  Malondialdehyde (MDA) dan SOD was measured with the ELISA and histopathology for muscle soleus and lung tissue.

Results: Strenuous exercise followed by RDF extract ingestion was compared for fatigue in terms of duration and time; before (24.55±1.38 minute) and after (95.31±7.82 minute) and led to a significant difference of 39% (p<0.01). The study also compared MDA before and after RDF extract ingestion in the K2 vs. the P1 group (p<0.05). At the same time, P2 differed more significantly (p<0.01). This indicated a spread of free radicals and featured histopathological damage of muscle cells. However, ingestion of RDF extract leads to improvement of soleus muscle cells; thus, repairs cell function, delaying fatigue.

Conclusion: This study confirmed that strenuous exercise, which causes an increase in ROS, intensifies free radicals with RDF extract ingestion and declines oxidative stress, repairing cell function and delaying fatigue.

Betalain-rich dragon fruit (pitaya) consumption improves vascular function in men and women: a double-blind, randomized controlled crossover trial

BACKGROUND

Betalains are natural red color pigments abundant in red-fleshed dragon fruit (Hylocereus polyrhizus). Recent research has shown that dragon fruit consumption may help improve blood glucose and lipid profile. However, investigations of its cardioprotective properties in human trials, especially in nutritionally achievable amounts, remain nonexistent.

OBJECTIVES

The aim of this study was to investigate the effects of acute and short-term consumption of dragon fruit on vascular function in a healthy population.

METHODS

A randomized, double-blind, placebo-controlled, crossover trial was conducted in 19 young, healthy, nonsmoking men and women assigned to consume 24 g whole dragon fruit powder (33 mg betalains) or a nutrient-matched placebo, daily for 14 d. Flow-mediated dilation (FMD), arterial stiffness, and blood pressure (BP) were measured at 0 h, 1 h, 2 h, 3 h, and 4 h and finally at 14 d after daily consumption.

RESULTS

A total of 18 participants completed the trial. Dragon fruit consumption significantly improved acute FMD at 2 h (+0.8 ± 0.3%, P = 0.01), 3 h (+1.0 ± 0.3%, P = 0.001), and 4 h (+1.3 ± 0.4%, P < 0.001) postconsumption compared with placebo. This effect was sustained up until 14 d (+1.3 ± 0.2%, P < 0.001). Pulse-wave velocity was acutely significantly reduced at 3 h (-0.5 ± 0.2 m/s, P = 0.003), whereas augmentation index (AIx) also improved after 14 d (-7.0 ± 3.3%, P = 0.02) when compared with placebo. No differences were found in either peripheral or central BP across all time points.

CONCLUSIONS

Acute and short-term consumption of dragon fruit in dietary achievable amounts improved endothelial function and arterial stiffness in healthy individuals. This implies that regular dragon fruit consumption may have a meaningful impact on cardiovascular disease risk likely due to the high betalain content. This trial was registered at ClinicalTrials.gov as NCT03995602.

Crosstalk relationship between adiponectin receptors, PPAR-γ and α-adrenoceptors in renal vasculature of diabetic WKYs

Hypoadiponectinemia is associated with renal dysfunctions. Irbesartan and pioglitazone activate Peroxisome proliferator-activated gamma receptor (PPAR-γ) as partial and full agonists. We investigated a crosstalk interaction and synergistic action between adiponectin receptors, PPAR-γ agonists in attenuating renal hemodynamics to adrenergic agonists in diabetic Wistar Kyoto rats (WKY). Streptozotocin (40 mg/kg) was used to induce diabetes, whereas, pioglitazone (10 mg/kg/day), irbesartan (30 mg/kg/day) administered orally for 28 days and adiponectin intraperitoneally (2.5 μg/kg/day) for last 7 days. Metabolic and plasma samples were analyzed on days 0, 8, 21, and 28. During the acute study (day 29), renal vasoconstrictor actions to adrenergic agonists and angiotensin-II were determined. Diabetic WKYs had lower plasma adiponectin, higher creatinine clearance, urinary and fractional sodium excretion but were normalized to a greater extent in pioglitazone and adiponectin combined treatment. Responses to intra-renal administration of adrenergic agonists including noradrenaline (NA), phenylephrine (PE), methoxamine (ME), and angiotensin-II (ANG-II) were larger in diabetic WKY, but significantly blunted with adiponectin treatment in diabetic WKYs to 35-40%, and further reduced by 65-70% in combination with pioglitazone. Attenuation to ANG-II responses in adiponectin and combination with irbesartan was 30-35% and 75-80%, respectively (P < 0.05). Pharmacodynamically, a crosstalk interaction exists between PPAR-γ, adiponectin receptors (adipo R1 & R2), alpha adrenoceptors, and angiotensin-I (ATI) receptors in the renal vasculature of diabetic WKYs. Exogenously administered adiponectin with full PPAR-γ agonist substantially attenuated renal hemodynamics and improved excretory functions, signifying their renoprotective action. Additionally, a degree of synergism exists between adiponectin and pioglitazone to a large extent compared to combination therapy with irbesartan (partial PPAR-γ agonist) in attenuating the renal vascular receptiveness to adrenergic agonists.

Minor tropical fruits as a potential source of bioactive and functional foods

Tropical fruits are defined as fruits that are grown in hot and humid regions within the Tropic of Cancer and Tropic of Capricorn, covering most of the tropical and subtropical areas of Asia, Africa, Central America, South America, the Caribbean and Oceania. Depending on the cultivation area covered, economic value and popularity these tropical fruits are divided into major and minor tropical fruits. There is an annual increment of 3.8% in terms of commercialization of the tropical fruits. In total 26 minor tropical fruits (Kiwifruit, Lutqua, Carambola, Tree Tomato, Elephant apple, Rambutan, Bay berry, Mangosteen, Bhawa, Loquat, Silver berry, Durian, Persimon, Longan, Passion fruit, Water apple, Pulasan, Indian gooseberry, Guava, Lychee, Annona, Pitaya, Sapodilla, Pepino, Jaboticaba, Jackfruit) have been covered in this work. The nutritional composition, phytochemical composition, health benefits, traditional use of these minor tropical fruits and their role in food fortification have been portrayed.

The effect of ingestion of red dragon fruit extract on levels of malondialdehyde and superoxide dismutase after strenuous exercise in rats ( Rattus norvegicus)

Background: Prolonged activation of skeletal muscles causes a decrease in the production of fatigue. Exercise with strenuous intensity causes an increase in Reactive Oxygen Species (ROS). An increase in free radicals causes oxidative stress resulting in damage to cell function to mitochondrial dysfunction, and fatigue. This study aimed to determine the antioxidant potential of red dragon fruit (RDF) to delay fatigue due to oxidative stress, which improves cell function in mitochondria. Methods: 25 male rats (Rattus norvegicus) aged three months were divided into five groups: Group K1 was N.A. (No Activity) but drinking and eating; Group K2 performed strenuous exercise without RDF treatment; Groups 3, 4, and 5 (P1, P2 and P3, respectively) performed strenuous exercise and were treated with 75 mg kg -1.bw, 150 mg kg -1.bw, and 300 mg kg -1.bw of RDF extract, respectively. The exercise for the rats involved intense swimming for 20 minutes  a day three time a week for fouweeks.  Malondialdehyde (MDA) dan SOD was measured with the ELISA and histopathology for muscle soleus and lung tissue. Results: Strenuous exercise followed by RDF extract ingestion was compared for fatigue in terms of duration and time; before (24.55±1.38 minute) and after (95.31±7.82 minute) and led to a significant difference of 39% (p<0.01). The study also compared MDA before and after RDF extract ingestion in the K2 vs. the P1 group (p<0.05). At the same time, P2 differed more significantly (p<0.01). This indicated a spread of free radicals and featured histopathological damage of muscle cells. However, ingestion of RDF extract leads to improvement of soleus muscle cells; thus, repairs cell function, delaying fatigue. Conclusion: This study confirmed that strenuous exercise, which causes an increase in ROS, intensifies free radicals with RDF extract ingestion and declines oxidative stress, repairing cell function and delaying fatigue.

Antioxidant Potential of Adiponectin and Full PPAR-γ Agonist in Correcting Streptozotocin-Induced Vascular Abnormality in Spontaneously Hypertensive Rats

Oxidative stress, which is associated with metabolic and anthropometric perturbations, leads to reactive oxygen species production and decrease in plasma adiponectin concentration. We investigated pharmacodynamically the pathophysiological role and potential implication of exogenously administered adiponectin with full and partial peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonists on modulation of oxidative stress, metabolic dysregulation, and antioxidant potential in streptozotocin-induced spontaneously hypertensive rats (SHR). Group I (WKY) serves as the normotensive control, whereas 42 male SHRs were randomized equally into 7 groups (n = 6); group II serves as the SHR control, group III serves as the SHR diabetic control, and groups IV, V, and VI are treated with irbesartan (30 mg/kg), pioglitazone (10 mg/kg), and adiponectin (2.5 μg/kg), whereas groups VII and VIII received cotreatments as irbesartan+adiponectin and pioglitazone+adiponectin, respectively. Diabetes was induced using an intraperitoneal injection of streptozotocin (40 mg/kg). Plasma adiponectin, lipid contents, and arterial stiffness with oxidative stress biomarkers were measured using an in vitro and in vivo analysis. Diabetic SHRs exhibited hyperglycemia, hypertriglyceridemia, hypercholesterolemia, and increased arterial stiffness with reduced plasma adiponectin and antioxidant enzymatic levels (P < 0.05). Diabetic SHRs pretreated with pioglitazone and adiponectin separately exerted improvements in antioxidant enzyme activities, abrogated arterial stiffness, and offset the increased production of reactive oxygen species and dyslipidemic effects of STZ, whereas the blood pressure values were significantly reduced in the irbesartan-treated groups (all P < 0.05). The combined treatment of exogenously administered adiponectin with full PPAR-γ agonist augmented the improvement in lipid contents and adiponectin concentration and restored arterial stiffness with antioxidant potential effects, indicating the degree of synergism between adiponectin and full PPAR-γ agonists (pioglitazone).

Peroxisome proliferator-activated receptor agonist (pioglitazone) with exogenous adiponectin ameliorates arterial stiffness and oxidative stress in diabetic Wistar Kyoto rats

Oxidative stress causes hypoadiponectemia and reactive oxygen species production. This study investigates the pathophysiological role and potential effects of adiponectin with partial and full peroxisome proliferator-activated receptor-gamma agonists on modulation of metabolic dysregulation and oxidative stress in diabetic model of Wistar Kyoto rats (WKY). Forty two male WKY rats were randomized equally into 7 groups (n = 6), Group I serve as control, group II as WKY diabetic control, groups III, IV and V treated with irbesartan (30 mg/kg), pioglitazone (10 mg/kg) and adiponectin (2.5 μg/kg), groups VI and VII were co-treated as: irbesartan + adiponectin, pioglitazone + adiponectin, respectively. Streptozotocin @ 40 mg/kg was administered intraperitoneally to induce diabetes. Plasma adiponectin, metabolic indices, pulse wave velocity, oxidative stress and antioxidant enzymatic activities were measured. Streptozotocin induced WKYs expressed hyperglycaemia, hypertriglyceridemia, hypercholesterolemia, hypoadiponectemia, increased arterial stiffness and decreased antioxidant enzymatic levels (P<0.05). Treatment with adiponectin or pioglitazone alone showed improvements in metabolic indices, antioxidant enzymes, and abrogated arterial stiffness, attenuated generation of reactive oxygen species and dyslipidaemic effects of streptozotocin better as compared to irbesartan sets of treatment (all P<0.05). Co-treatment of adiponectin with pioglitazone significantly amplified the improvement in plasma triglycerides, adiponectin concentration, pulse wave velocity and antioxidant enzymatic activities indicating synergistic effects of adiponectin with full PPAR-γ agonist.

Postharvest Quality of Cherry Tomatoes Coated with Mucilage from Dragon Fruit and Irradiated with UV-C

Cherry tomatoes are climacteric fruits that have a limited shelf life. Over the years, many methods have been applied to preserve the fruit quality and safety of these fruits. In this study, a novel method of combining mucilage from dragon fruits and UV-C irradiation was carried out. Cherry tomatoes were subjected to UV-C irradiation and edible coating, both as a stand-alone and hurdle treatment. The edible coating was prepared from the mucilage of white dragon fruits. Quality parameters including color, weight loss, total soluble solids, titratable acidity, ascorbic acid, antioxidant analysis (total phenolic content and flavonoid content), and microbial analysis were measured throughout 21 days of storage at 4 °C. Results showed that the hurdle treatment extended shelf life by 21 days, reduced weight loss (0.87 ± 0.05%) and color changes (11.61 ± 0.95 ΔE), and inhibited microbes better than stand-alone treatments. Furthermore, fruits treated with the combination of UV-C and edible coating also contained higher total polyphenol content (0.132 ± 0.003 mg GAE/100 mL), total flavonoid content (13.179 ± 0.002 mg CE/100 mL), and ascorbic acid (1.07 ± 0.06 mg/100 mL). These results show that the combination of UV-C and edible coating as a hurdle treatment could be an innovative method to preserve shelf life and quality of fruits.

The restorative effect of apocynin and catalase in l-arginine induced hypotension on normotensive subjects – the role of oxidative stress

L-arginine is a substrate for nitric oxide synthase (NOS) responsible for the production of NO. This investigation studied the effect of apocynin, an NADPH oxidase inhibitor and catalase, an H2O2 scavenger on L-arginine induced oxidative stress and hypotension. Forty Wistar-Kyoto rats were treated for 14 days with vehicle, L-arginine (12.5mg/ml p.o.), L-arginine+apocynin (2.5mmol/L p.o.), L-arginine+catalase (10000U/kg/day i.p.) and L-arginine plus apocynin+catalase respectively. Weekly renal functional and hemodynamic parameters were measured and kidneys harvested at the end of the study for histopathological and renal NADPH oxidase 4 (Nox4) assessments. L-arginine administration in normotensive rats decreased systolic blood pressure (120±2 vs 91±2mmHg) and heart rate (298±21 vs 254±15b/min), enhanced urinary output (21.5±4.2 vs 32±1.9ml/24h , increased creatinine clearance (1.72±0.56 vs 2.62±0.40ml/min/kg), and fractional sodium excretion (0.88±0.16 vs 1.18±0.16 %), caused proteinuria (28.10±1.93 vs 35.26±1.69mg/kg/day) and a significant decrease in renal cortical blood perfusion (292±3 vs 258±5bpu) and pulse wave velocity (3.72±0.20 vs 2.84±0.13m/s) (all P<0.05). L-arginine increased plasma malondialdehyde (by ~206 % P<0.05) and NO (by ~51 %, P<0.05) but decreased superoxide dismutase (by ~31 %, P<0.05) and total antioxidant capacity (by ~35 %, P<0.05) compared to control. Renal Nox4 mRNA activity was approximately 2.1 fold higher (P<0.05) in the L-arginine treated rats but was normalized by apocynin and apocynin plus catalase treatment. Administration of apocynin and catalase, but not catalase alone to rats fed L-arginine, restored the deranged renal function and structure, prevented hypotension and enhanced the antioxidant capacity and suppressed Nox4 expression. These findings suggest that apocynin and catalase might be used prophylactically in states of oxidative stress.

Phenolic Compounds in Mesoamerican Fruits-Characterization, Health Potential and Processing with Innovative Technologies

Diets rich in phenolic compounds have been associated to reducing the risk of metabolic syndrome and its derived disorders. Fruits are healthy components of the human diet because of their vitamin, mineral, fiber and phenolic profile. However, they have a short shelf-life which is limited by microbiological growth and enzymatic activity. Innovative preservation methods such as high hydrostatic pressure, pulsed electric fields, ultrasound, microwave, cold plasma and ultraviolet light have become popular for the processing of fruits because they can preserve nutritional quality. In this review, the phenolic profile and health potential of 38 Mesoamerican fruits were assessed. Phenolic compounds were classified based on their contribution to the diet as flavonoids, phenolic acids, tannin, lignins and stilbenoids. Due to this composition, fruits showed a wide range of bioactivities which included anti-inflammatory, anti-diabetic, anti-hypertensive and anti-obesity activities, among others. Phenolic content in fruits submitted to innovative food processing technologies depended on parameters such as enzymatic activity, antioxidant capacity, microstructure integrity and cell viability. Innovative technologies could increase phenolic content while assuring microbiological safety by (i) promoting the release of bound phenolic compounds during processing and (ii) inducing the synthesis of phenolic compounds by activation of phenylpropanoid pathway during storage.

The effects of betalain-rich cacti (dragon fruit and cactus pear) on endothelial and vascular function: a systematic review of animal and human studies

Dragon fruit (Hylocereus) and cactus pear (Opuntia) are cacti species that have been widely used globally as a reliable source of food as well as traditional folk remedies. They have become of scientific interest recently due to their high levels of bioactive phytochemical compounds, in particular betalains. Earlier systematic reviews have explored the impact of supplementation of these cactus species on obesity, type-2 diabetes mellitus and cardiovascular risk factors: body weight and composition, serum triglycerides, cholesterol, blood glucose and blood pressure. However, effects on vascular health and endothelial function have yet to be reviewed. In order to address this gap in the literature, a systematic review has been conducted to evaluate the physiological effects of Hylocereus and Opuntia cacti on endothelial and vascular function in in vivo animal models and human studies. An electronic search was performed in the following databases: PubMed (MEDLINE), EMBASE (via Ovid), CINAHL, Scopus, Web of Science®, and The Cochrane Library (CENTRAL). All journals were searched since inceptions up to January 2020 without language restriction. Outcomes of interest were blood pressure, arterial stiffness, vascular reactivity and biochemical markers of endothelial dysfunction. Two investigators independently performed the study selection and data extraction. From 394 references, only 16 studies (9 animal and 7 human) fulfilled the eligibility criteria. Animal studies suggested a potential increase in vasodilation and serum nitric oxide and a reduction in vascular stiffness and blood pressure. The small number of human studies showed a reduction in heart rate as well as an increase in heart rate variability. Although these findings appear to indicate improvement in vascular health, there is a severe lack of robust, randomised human intervention studies to identify underlying mechanisms, optimal dose and long-term effects of cacti consumption.

Contribution of anthocyanin pathways to fruit flesh coloration in pitayas

BACKGROUND

Color formation in Hylocereus spp. (pitayas) has been ascribed to the accumulation of betalains. However, several studies have reported the presence of anthocyanins in pitaya fruit and their potential role in color formation has not yet been explored. In this study, we profiled metabolome and transcriptome in fruit of three cultivars with contrasting flesh colors (red, pink and white) to investigate their nutritional quality and the mechanism of color formation involving anthocyanins.

RESULTS

Results revealed that pitaya fruit is enriched in amino acid, lipid, carbohydrate, polyphenols, vitamin and other bioactive components with significant variation among the three cultivars. Anthocyanins were detected in the fruit flesh and accumulation levels of Cyanidin 3-glucoside, Cyanidin 3-rutinoside, Delphinidin 3-O-(6-O-malonyl)-beta-glucoside-3-O-beta-glucoside and Delphinidin 3-O-beta-D-glucoside 5-O-(6-coumaroyl-beta-D-glucoside) positively correlated with the reddish coloration. Transcriptome data showed that the white cultivar tends to repress the anthocyanin biosynthetic pathway and divert substrates to other competing pathways. This perfectly contrasted with observations in the red cultivar. The pink cultivar however seems to keep a balance between the anthocyanin biosynthetic pathway and the competing pathways. We identified several active transcription factors of the MYB and bHLH families which can be further investigated as potential regulators of the anthocyanin biosynthetic genes.

CONCLUSIONS

Collectively, our results suggest that anthocyanins partly contribute to color formation in pitaya fruit. Future studies aiming at manipulating the biosynthetic pathways of anthocyanins and betalains will better clarify the exact contribution of each pathway in color formation in pitayas. This will facilitate efforts to improve pitaya fruit quality and appeal.

Phytoconstituents and pharmaco-therapeutic benefits of pitaya: A wonder fruit

Dragon fruit has caught the attention of many researchers in the last few years because of its vast therapeutic potential. The fruit is enriched with several phytochemical constituents having tremendous pharmacological properties. It is traditionally used as a coloring agent. Some newly explored therapeutic applications include its use as an antioxidant, antimicrobial, antidiabetic, anticancer, and nutraceutical. The phytoconstituents can be extracted from flesh, peel, and seeds of the fruit. The fruit is known to be a rich source of betacyanin, vitamin C, and lycopene. The current review is focused on phytochemical constituents of dragon fruit along with its pharmacological activities. It also sheds light on the safety aspects of the fruit. The review will pave a path for researchers to study this marvel fruit further for societal benefit. Advanced research on dragon fruit will unleash many more therapeutic benefits and can give mechanistic insight about its activities. PRACTICAL APPLICATIONS: Phytoconstituents play a vital role in the treatment of various diseases and for the improvement of human health, in general. Dragon fruit is known to be having antioxidant, anti-microbial, anti-diabetic, anti-cancer applications. The fruit can also be used as a nutraceutical (functional food). To grab all the benefits from this fruit, its phytoconstituents and pharmaco-therapeutic aspect have to be thoroughly studied. This review can be very useful for researchers across different fields like botany, agriculture, pharmacy, etc., to bridge the gap for collaborative work on dragon fruit, which will help in finding solutions for many modern diseases.

Effect of gasotransmitters treatment on expression of hypertension, vascular and cardiac remodeling and hypertensive nephropathy genes in left ventricular hypertrophy

BACKGROUND

Cardiac and renal dysfunction are often co-morbid pathologies leading to worsening prognosis resulting in difficulty in therapy of left ventricular hypertrophy (LVH). The aim of the current study was to determine the changes in expression of human ortholog genes of hypertension, vascular and cardiac remodeling and hypertensive nephropathy phenotypes under normal, disease and upon treatment with gasotransmitter including H₂S (hydrogen sulphide), NO (nitric oxide) and combined (H₂S + NO).

METHODS

A total of 72 Wistar Kyoto rats (with equivalent male and female animals) were recruited in the present study where LVH rat models were treated with H₂S and NO individually as well as with both combined. Cardiac and renal physical indices were recorded and relative gene expression were quantified.

RESULTS

Both cardiac and renal physical indices were significantly modified with individual as well as combined H₂S + NO treatment in control and LVH rats. Expression analysis revealed, hypertension, vascular remodeling genes ACE, TNFα and IGF1, mRNAs to be significantly higher (P ≤ 0.05) in the myocardia and renal tissues of LVH rats, while individual and combined H₂S + NO treatment resulted in lowering the gene expression to normal/near to normal levels. The cardiac remodeling genes MYH7, TGFβ, SMAD4 and BRG1 expression were significantly up-regulated (P ≤ 0.05) in the myocardia of LVH where the combined H₂S + NO treatment resulted in normal/near to normal expression more effectively as compared to individual treatments. In addition individual as well as combined H₂S and NO treatment significantly decreased PKD1 expression in renal tissue, which was up-regulated in LVH rats (P ≤ 0.05).

CONCLUSIONS

The reduction in hemodynamic parameters and cardiac indices as well as alteration in gene expression on treatment of LVH rat model indicates important therapeutic potential of combined treatment with H₂S + NO gasotransmitters in hypertension and cardiac hypertrophy when present as co-morbidity with renal complications.

Apocynin and catalase prevent hypertension and kidney injury in Cyclosporine A-induced nephrotoxicity in rats

Oxidative stress is involved in the pathogenesis of a number of diseases including hypertension and renal failure. There is enhanced expression of nicotinamide adenine dinucleotide (NADPH oxidase) and therefore production of hydrogen peroxide (H2O2) during renal disease progression. This study investigated the effect of apocynin, an NADPH oxidase inhibitor and catalase, an H2O2 scavenger on Cyclosporine A (CsA) nephrotoxicity in Wistar-Kyoto rats. Rats received CsA (25mg/kg/day via gavage) and were assigned to vehicle, apocynin (2.5mmol/L p.o.), catalase (10,000U/kg/day i.p.) or apocynin plus catalase for 14 days. Renal functional and hemodynamic parameters were measured every week, and kidneys were harvested at the end of the study for histological and NADPH oxidase 4 (NOX4) assessment. Oxidative stress markers and blood urea nitrogen (BUN) were measured. CsA rats had higher plasma malondialdehyde (by 340%) and BUN (by 125%), but lower superoxide dismutase and total antioxidant capacity (by 40%, all P<0.05) compared to control. CsA increased blood pressure (by 46mmHg) and decreased creatinine clearance (by 49%, all P<0.05). Treatment of CsA rats with apocynin, catalase, and their combination decreased blood pressure to near control values (all P<0.05). NOX4 mRNA activity was higher in the renal tissue of CsA rats by approximately 63% (P<0.05) compared to controls but was reduced in apocynin (by 64%), catalase (by 33%) and combined treatment with apocynin and catalase (by 84%) compared to untreated CsA rats. Treatment of CsA rats with apocynin, catalase, and their combination prevented hypertension and restored renal functional parameters and tissue Nox4 expression in this model. NADPH inhibition and H2O2 scavenging is an important therapeutic strategy during CsA nephrotoxicity and hypertension.

Effect of dragon fruit on glycemic control in prediabetes and type 2 diabetes: A systematic review and meta-analysis

Objective

The purpose of this study was to systematically determine the effect of dragon fruit on glycemic control in prediabetes and type 2 diabetes.

Methods

Electronic databases including MEDLINE, CENTRAL, CINAHL, Scopus, ScienceDirect^®, Proquest, Web of Science^®, LILACS, NAPRALERT, SciFinder, Clinicalkey, Herbmed, NCCIH and Google Scholar were searched from their earliest inception up to March 2017 for relevant randomized controlled trials (RCTs) which compared dragon fruit with placebo or no treatment in prediabetes or type 2 diabetes. Clinicaltrials.gov, clinicaltrialresults.org, and ISRCTN registry were also searched. Personal contact with experts and historical search of related articles was undertaken. Outcome of interest were fasting plasma glucose (FPG) and 2 hours post-prandial glucose (2HPP). Study selection, data extraction and study quality assessment were performed independently by two investigators. Disagreements were resolved by a third reviewer. Treatment effect was estimated with mean difference (MD). Effect estimates were pooled using inverse-variance weighted method. Heterogeneity was assessed with the Q statistic and quantified with the I² statistic. DerSimonian and Laird random-effects model was used when the Q-statistic was significant at the level of 0.1, otherwise a fixed-effects model was used.

Results

Among 401 studies identified from literature search, 4 RCTs involving 36 prediabetes subjects and 109 type 2 diabetes patients were included in the analysis. In prediabetes, FPG reduction was significant with MD of -15.1 mg/dL (95% CI: -23.8 to -6.5 mg/dL, P-value = 0.0006). Meta-analysis in type 2 diabetes showed no effect of dragon fruit on FPG (MD -26.5 mg/dL, 95% CI: -72.6 mg/dL to 19.6 mg/dL) and in 2HPP (MD -30.5 mg/dL, 95% CI: -80.9 mg/dL to 19.9 mg/dL).

Conclusion

The available evidence in prediabetes is interesting. This will shed some light on diabetes prevention. The effect in T2DM was not significant. However, a trend towards greater blood glucose reduction with higher dose was observed.

Up Regulation of cystathione γ lyase and Hydrogen Sulphide in the Myocardium Inhibits the Progression of Isoproterenol-Caffeine Induced Left Ventricular Hypertrophy in Wistar Kyoto Rats

Hydrogen sulphide (H2S) is an emerging molecule in many cardiovascular complications but its role in left ventricular hypertrophy (LVH) is unknown. The present study explored the effect of exogenous H2S administration in the regression of LVH by modulating oxidative stress, arterial stiffness and expression of cystathione γ lyase (CSE) in the myocardium. Animals were divided into four groups: Control, LVH, Control-H2S and LVH-H2S. LVH was induced by administering isoprenaline (5mg/kg, every 72 hours, S/C) and caffeine in drinking water (62mg/L) for 2 weeks. Intraperitoneal NaHS, 56μM/kg/day for 5 weeks, was given as an H2S donor. Myocardial expression of Cystathione γ lyase (CSE) mRNA was quantified using real time polymerase chain reaction (qPCR).There was a 3 fold reduction in the expression of myocardial CSE mRNA in LVH but it was up regulated by 7 and 4 fold in the Control-H2S and LVH-H2S myocardium, respectively. Systolic blood pressure, mean arterial pressure, pulse wave velocity were reduced (all P<0.05) in LVH-H2S when compared to the LVH group. Heart, LV weight, myocardial thickness were reduced while LV internal diameter was increased (all P<0.05) in the LVH-H2S when compared to the LVH group. Exogenous administration of H2S in LVH increased superoxide dismutase, glutathione and total antioxidant capacity but significantly reduced (all P<0.05) plasma malanodialdehyde in the LVH-H2S compared to the LVH group. The renal cortical blood perfusion increased by 40% in LVH-H2S as compared to the LVH group. Exogenous administration of H2S suppressed the progression of LVH which was associated with an up regulation of myocardial CSE mRNA/ H2S and a reduction in pulse wave velocity with a blunting of systemic hemodynamic. This CSE/H2S pathway exhibits an antihypertrophic role by antagonizing the hypertrophic actions of angiotensin II(Ang II) and noradrenaline (NA) but attenuates oxidative stress and improves pulse wave velocity which helps to suppress LVH. Exogenous administration of H2S augmented the reduced renal cortical blood perfusion in the LVH state.

Ellagic acid ameliorates lung injury after intestinal ischemia-reperfusion

Background:

The aim of this study was to investigate the possible protective role of antioxidant treatment with ellagic acid (EA) on lung injury after intestinal ischemia-reperfusion (I/R) injury using biochemical and histopatological approaches.

Materials and Methods:

Forty rats were divided into four groups as control, control + EA, I/R, and I/R + EA. The control and control + EA groups were also anesthetized and subjected to laparotomy, but without clamp application. The control + EA and I/R + EA groups were given EA (85 mg/kg) orally prior to experiment. The I/R and I/R + EA groups underwent 30 minutes of intestinal ischemia and 1 hour of reperfusion. In all groups, serum total antioxidant capacity (TAC) and malondialdehyde (MDA) levels were determined. TAC, total oxidative status (TOS), and oxidative stress index (OSI) in lung tissue were measured. Lung tissue histopathology was also evaluated by light microscopy.

Results:

TAC levels were higher in control, EA, and I/R + EA groups while TOS, OSI, and MDA levels were lower in these groups compared with I/R group. Serum MDA levels were significantly higher in I/R + EA group than that of control group. Lung tissue TAC levels were lower in I/R + EA group while OSI values were higher in that groups compared with EA group. Histological tissue damage was milder in the EA treatment group than in the I/R group.

Conclusion:

These results suggest that EA treatment protected the rats lung tissue against intestinal I/R injury.