Diabetes: a pandemic, a development issue or both?

Hibiscus sabdariffa L. polyphenolic-rich extract promotes muscle glucose uptake and inhibits intestinal glucose absorption with concomitant amelioration of Fe2+ -induced hepatic oxidative injury

In this current study, the antidiabetic effectiveness of Hibiscus sabdariffa and its protective function against Fe²⁺ -induced oxidative hepatic injury were elucidated using in vitro, in silico, and ex vivo studies. The oxidative damage was induced in hepatic tissue by incubation with 0.1 mMolar ferrous sulfate (FeSO4) and then treated with different concentrations of crude extracts (ethyl acetate, ethanol, and aqueous) of H. sabdariffa flowers for 30 min at 37°C. When compared to ethyl acetate and aqueous extracts, the ethanolic extract displayed the most potent scavenging activity in ferric-reducing antioxidant power (FRAP), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and nitric oxide (NO) assays, with IC₅₀ values of 2.8 μl/ml, 3.3 μl/ml, and 9.2 μl/ml, respectively. The extracts significantly suppressed α-glucosidase and α-amylase activities (p < .05), with the ethanolic extract demonstrating the highest activity. H. sabdariffa significantly (p < .05) raised reduced glutathione (GSH) levels while simultaneously decreasing malondihaldehyde (MDA) and NO levels and increasing superoxide dismutase (SOD) and catalase activity in Fe²⁺ induced oxidative hepatic injury. The extract of the plant inhibited intestinal glucose absorption and increased muscular glucose uptake. The extract revealed the presence of several phenolic compounds when submitted to gas chromatography-mass Spectroscopy (GC-MS) screening, which was docked with α-glucosidase and α- amylase. The molecular docking displayed the compound 4-(3,5-Di-tert-butyl-4-hydroxyphenyl)butyl acrylate strongly interacted with α-glucosidase and α-amylase and had the lowest free binding energy compared to other compounds and acarbose. These results suggest that H. sabdariffa has promising antioxidant and antidiabetic activity. PRACTICAL APPLICATIONS: In recent years, there has been increased concern about the side effects of synthetic anti-diabetic drugs, as well as their expensive cost, especially in impoverished nations. This has instigated a radical shift towards the use of traditional plants, which are rich in phytochemicals many years ago. Among these plants, H. sabdariffa has been used to treat diabetes in traditional medicine. In this present study, H. sabdariffa extracts demonstrated the ability to inhibit carbohydrate digesting enzymes, facilitate muscle glucose uptake and attenuate oxidative stress in oxidative hepatic injury. Hence, demonstrating H. sabdariffa's potential to protect against oxidative damage and the complications associated with diabetes. Consumption of Hibiscus tea or juice may be a potential source for developing an anti-diabetic drug.

Modelling geographical heterogeneity of diabetes prevalence and socio-economic and built environment determinants in Saudi City - Jeddah

Type-2 diabetes is a growing lifestyle disease mainly due to increasing physical inactivity but also associated with various other variables. In Saudi Arabia, around 58.5% of the population is deemed to be physically inactive. Against this background, this study attempts explore the spatial heterogeneity of Type-2 diabetes prevalence in Jeddah and to estimate various socio-economic and built environment variables contributing to the prevalence of this disease based on modelling by ordinary least squares (OLS), weighted regression (GWR) and multi-scale geographically weighted (MGWR). Our OLS results suggest that income, population density, commercial land use and Saudi population characteristics are statistically significant for Type-2 diabetes prevalence. However, by the GWR model, income, commercial land use and Saudi population characteristics were significantly positive while population density was significantly negative in this model for 70.6%, 9.1%, 26.6% and 58.7%, respectively, out of 109 districts investigated; by the MGWR model, the corresponding results were 100%, 22%, 100% and 100% of the districts. With the given data, the corrected Akaike information criterion (AICc), the adjusted R2, the log-likelihood and the residual sum of squares (RSS) indices demonstrated that the MGWR model outperformed the GWR and OLS models explaining 29% more variance than the OLS model, and 10.2% more than the GWR model. These results support the development of evidence-based policies for the spatial allocation of health associated resources for the control of Type-2 diabetes in Jeddah and other cities in the Arabian Gulf.

Chemical Group Profiling, In Vitro and In Silico Evaluation of Aristolochia ringens on α-Amylase and α-Glucosidase Activity

Diabetes mellitus (DM) has become a global scourge, and there is a continuous search for novel compounds as viable alternatives to synthetic drugs which are often accompanied by severe adverse effects. Aristolochia ringens is among the scientifically implicated botanicals effective in the management of several degenerative diseases including DM. The current study evaluated the inhibitory mechanism(s) of root extract of A. ringens on α-amylase and α-glucosidase in vitro and in silico, while its constituents were characterized using liquid chromatography-mass spectrometric technique. The extract had concentration-dependent inhibitory effect on the study enzymes, and the inhibition compared well with that of standard drug (acarbose) with respective IC₅₀ values of 0.67 mg/mL (α-amylase) and 0.57 mg/mL (α-glucosidase) compared with that of the extract (0.63 and 0.54 mg/mL). The extract competitively and uncompetitively inhibited α-amylase and α-glucosidase, respectively. Of the identified compounds, dianoside G (−12.4, −12.5 kcal/mol) and trilobine (−10.0, −10.0 kcal/mol) had significant interactions with α-amylase and α-glucosidase, respectively, while magnoflorine and asiatic acid also interacted keenly with both enzymes, with quercetin 3-O-glucuronide and strictosidine showing better affinity towards α-glucosidase. These observations are suggestive of involvement of these compounds as probable ligands contributing to antidiabetic potential of the extract. While studies are underway to demystify the yet to be identified compounds in the extract, the data presented have lent scientific credence to the acclaimed in vivo antidiabetic potential of the extract and suggested it as a viable source of oral hypoglycaemic agent.

Cross-talk between 10-gingerol and its anti-cancerous potential: a recent update

Since time immortal, ginger, as an ancient herb, has been used throughout the world in foods and beverages due to its typical strong and pungent flavor. Besides its use as a spice, it also serves as an excellent source of several bioactive phenolics, including nonvolatile pungent compounds, such as gingerols, paradols, shogaols, and gingerones. Gingerols constitute key ingredients in fresh ginger, with the most abundant being 6-gingerol (6-G), 8-gingerol (8-G), and 10-gingerol (10-G). Many studies have investigated the various valuable pharmacological properties of these ingredients and experimentally verified the mechanistic aspects of their health effects; however, to date, most research on the anti-cancerous activities of gingerols have focused largely on 6-G. Thus, the present article deals with the number of recent studies that have indicated and highlighted the role of 10-G with respect to its cancer prevention attributes in particular and its anti-inflammatory, anti-oxidant, anti-microbial, and gastrointestinal tract protective potential in general. The purpose of this review is to provide an overview of all the experimentally validated health benefits of 10-G for nutraceutical applications. The various findings have warranted the further investigation of 10-G and its possible use in various cancer treatments as well as its promising role as a chemo-preventive agent.

Development of a UPLC-MS/MS Method for Simultaneous Determination of Six Flavonoids in Rat Plasma after Administration of Maydis stigma Extract and Its Application to a Comparative Pharmacokinetic Study in Normal and Diabetic Rats

Maydis stigma is an important medicine herb used in many parts of the world for treatment of diabetes mellitus, which main bioactive ingredients are flavonoids. This paper describes for the first time a study on the comparative pharmacokinetics of six active flavonoid ingredients of Maydis stigma in normal and diabetic rats orally administrated with the decoction. Therefore, an efficient and sensitive ultra high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of six anti-diabetic ingredients (cynaroside, quercetin, luteolin, isorhamnetin, rutin and formononetin) of Maydis stigma in rat plasma has been developed and validated in plasma samples, which showed good linearity over a wide concentration range (r² > 0.99), and gave a lower limit of quantification of 1.0 ng·mL⁻¹ for the analytes. The intra- and interday assay variability was less than 15% for all analytes. The mean extraction recoveries and matrix effect of analytes and IS from rats plasma were all more than 85.0%. The stability results showed the measured concentration for six analytes at three QC levels deviated within 15.0%. The results indicated that significant differences in the pharmacokinetic parameters of the analytes were observed between the two groups of animals, whereby the absorptions of these analytes in the diabetic group were all significantly higher than those in the normal group, which provides an experimental basis for the role of Maydis stigma in anti-diabetic treatment.

KINETICS OF MODULATORY ROLE OF Cyperus esculentus L. ON THE SPECIFIC ACTIVITY OF KEY CARBOHYDRATE METABOLIZING ENZYMES

Background:

The continuous search for new lead compounds as viable inhibitors of specific enzymes linked to carbohydrate metabolism has intensified. Cyperus esculentus L. is one of the therapeutically implicated botanicals against several degenerative diseases including diabetes mellitus.

Materials and Methods:

This study evaluated the antioxidant and mechanism(s) of inhibitory potential of aqueous extract of C. esculentus on α-amylase and α-glucosidase in vitro. The extract was investigated for its radical scavenging and hypoglycaemic potentials using standard experimental procedures. Lineweaver-Burke plot was used to predict the manner in which the enzymes were inhibited.

Results:

The data obtained revealed that the extract moderately and potently inhibited the specific activities of α-amylase and α-glucosidase, respectively. The inhibition was concentration-related with respective IC₅₀ values of 5.19 and 0.78 mg/mL relative to that of the control (3.72 and 3.55 mg/mL). The extract also significantly scavenged free radicals and the effects elicited could be ascribed to its phytoconstituents.

Conclusion:

The respective competitive and non-competitive mode of action of the extract is due to its inhibitory potentials on the activities of α-amylase and α-glucosidase. Going forward, in addition to completely characterize the exact compound(s) responsible for the elicited activity in this study, pertinent attention will be given to the in vivo evaluation of the identified constituents.

Evaluation of daily ginger consumption for the prevention of chronic diseases in adults: A cross-sectional study

OBJECTIVES

The aim of this study was to assess daily ginger consumption and explore its correlation with chronic diseases among adults and to analyze further how different levels of ginger intake affect the prevalence of chronic diseases.

METHODS

We examined the prevalence rate of chronic diseases (diabetes, hypertension, coronary heart disease [CHD], hyperlipidemia, cerebrovascular disease, fatty liver, anemia, and tumor), as well as the daily ginger intake in a large cross-sectional study. In all, 4628 participants (1823 men and 2805 women) ages 18 to 77 y completed face-to-face dietary and health questionnaires. We extracted diagnoses and investigation results from the participants' health records. The association between the level of ginger intake (0-2 g/d, 2-4 g/d, and 4-6 g/d) and the prevalence of chronic diseases was analyzed by using χ2 statistical test and unconditional logistic model.

RESULTS

Overall, daily ginger consumption was associated with decreased risk for hypertension (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.86-0.98) and CHD (OR, 0.87; 95% CI, 0.78-0.96) in adults ages ≥18 y. Differences were also observed in adults ages ≥40 y: hypertension (OR, 0.92; 95% CI, 0.87-0.99), CHD (OR, 0.87; 95% CI, 0.78-0.97). However, after 20 y, no association was seen for hypertension but there was still a difference between ginger consumption and CHD in adults ages ≥60 y (OR, 0.84; 95% CI, 0.73-0.96). Again, the probability of illness (hypertension or CHD) decreased when the level of daily ginger intake increased.

CONCLUSIONS

These data indicate that ginger has a potential preventive property against some chronic diseases, especially hypertension and CHD, as well as its ability to reduce the probability of illness.

Reactive oxygen species: sources, consequences and targeted therapy in type 2 diabetes

Oxidative stress has been considered as a central mediator in the progression of diabetic complication. The intracellular reactive oxygen species (ROS) leads to oxidative stress and it is raised from the mitochondria as well as by activation of five major pathways: increased polyol pathway flux, activation of protein kinase C (PKC) pathway, increased formation of advanced glycation end products (AGEs), over activity of hexosamine pathway and increased production of angiotensin II. The increased ROS through these pathways leads to β-cell dysfunction and insulin resistance, responsible for cell damage and death. This review not only highlights the sources of ROS production and their involvement in the progression of diabetes, but also emphasizes on pharmacological interventions and targeting of ROS in type 2 diabetes. This review summarizes the ROS as potential therapeutic targets, based on a putative mechanism in the progression of the diabetes. It also summarizes current knowledge of ROS activation in type 2 diabetes as well as ROS as a possible target for its treatment. Eventually, it would be a promising target for various strategies and drugs to modulate ROS levels in diabetes.

Kinetics of α-amylase and α-glucosidase inhibitory potential of Zea mays Linnaeus (Poaceae), Stigma maydis aqueous extract: An in vitro assessment

ETHNOPHARMACOLOGICAL RELEVANCE

Corn silk (Zea mays L., Stigma maydis) is an important herb used traditionally in many parts of the world to treat array of diseases including diabetes mellitus. Inhibitors of α-amylase and α-glucosidase offer an effective strategy to modulate levels of post prandial hyperglycaemia via control of starch metabolism.

AIM OF THE STUDY

This study evaluated α-amylase and α-glucosidase inhibitory potentials of corn silk aqueous extract. Active principles and antioxidant attributes of the extract were also analysed.

MATERIALS AND METHODS

The α-amylase inhibitory potential of the extract was investigated by reacting its different concentrations with α-amylase and starch solution, while α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extract followed by addition of p-nitrophenylglucopyranoside. The mode(s) of inhibition of the enzymes were determined using Lineweaver-Burke plot.

RESULTS

In vitro analysis of the extract showed that it exhibited potent and moderate inhibitory potential against α-amylase and α-glucosidase, respectively. The inhibition was concentration-dependent with respective half-maximal inhibitory concentration (IC50) values of 5.89 and 0.93mg/mL. Phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols, saponins, tannins and phytosterols as probable inhibitory constituents. Furthermore, the extract remarkably scavenges reactive oxygen species like DPPH and nitric oxide radicals, elicited good reducing power and a significant metal chelating attributes.

CONCLUSION

Overall, the non-competitive and uncompetitive mechanism of action of corn silk extract is due to its inhibitory effects on α-amylase and α-glucosidase, respectively. Consequently, this will reduce the rate of starch hydrolysis, enhance palliated glucose levels, and thus, lending credence to hypoglycaemic candidature of corn silk.

The reliability and validity of the diabetes care profile for Chinese populations

This study aimed to translate into Chinese the Diabetes Care Profile (DCP), a measure of psychosocial factors and diabetes treatment, and to test the reliability and validity of the instrument within a Chinese population. The English version of the DCP was translated into Chinese following the standard translation methodology with consideration to cultural adaptation. The questionnaire was administered to 313 people with type 2 diabetes in an urban community in Beijing, China. Cronbach's α coefficient was used to calculate reliabilities, which ranged from .55 to .86 on DCP subscales. Mean values on the DCP differed by diabetes treatment as expected and supports the construct validity of the DCP. The overall score on the DCP correlated well both with blood glucose levels and with a validated measure of a Chinese version of the Diabetes Specific Quality of Life scale, thus supporting the DCP's criterion validity. The DCP is an acceptable measure of the psychosocial factors related to diabetes and its treatment in a Chinese population with type 2 diabetes.

Intrauterine growth restriction coupled with hyperglycemia: effects on cardiac structure in adult rats

BACKGROUND

Intrauterine growth restriction (IUGR) has been linked to heart disease in adulthood. Hence the IUGR heart is likely to be vulnerable to diabetic heart disease. The aim of this study was to examine the effect of induction of type 1 diabetes on myocardial collagen deposition and cardiac function in adult rats with a history of IUGR, after controlling blood glucose levels.

METHODS

IUGR was induced by protein restriction in the pregnant female rat. When the offspring were 24 wk of age, diabetes was induced in male IUGR and non-IUGR rats by means of streptozotocin; insulin injections were used to maintain blood glucose levels at a mild (7-10 mmol/l; n = 8 per group) or moderate level (10-15 mmol/l; n = 8 per group). Echocardiography and cardiac morphology analyses were carried out when the rats were 32 wk of age.

RESULTS

IUGR offspring exhibited cardiac hypertrophy at 32 wk, including a thicker posterior wall and increased interstitial fibrosis in the left ventricle. Hyperglycemia led to an increase in heart size and myocardial fibrosis. The response to hyperglycemia was not different between IUGR and non-IUGR rats; however, cardiac fibrosis was greatest when diabetes was present along with a history of IUGR. In general, maintaining blood glucose levels at a mildly hyperglycemic level attenuated the adverse effects of hyperglycemia but did not reverse the fibrosis.

CONCLUSION

Exacerbated fibrosis in hyperglycemic hearts of IUGR offspring may lead to long-term cardiac dysfunction.

A pharmacological appraisal of medicinal plants with antidiabetic potential

Diabetes mellitus is a complicated metabolic disorder that has gravely troubled the human health and quality of life. Conventional agents are being used to control diabetes along with lifestyle management. However, they are not entirely effective and no one has ever been reported to have fully recovered from diabetes. Numerous medicinal plants have been used for the management of diabetes mellitus in various traditional systems of medicine worldwide as they are a great source of biological constituents and many of them are known to be effective against diabetes. Medicinal plants with antihyperglycemic activities are being more desired, owing to lesser side-effects and low cost. This review focuses on the various plants that have been reported to be effective in diabetes. A record of various medicinal plants with their established antidiabetic and other health benefits has been reported. These include Allium sativa, Eugenia jambolana, Panax ginseng, Gymnema sylvestre, Momrodica charantia, Ocimum sanctum, Phyllanthus amarus, Pterocarpus marsupium, Trigonella foenum graecum and Tinospora cordifolia. All of them have shown a certain degree of antidiabetic activity by different mechanisms of action.

Effective communication is crucial to self-management: the experiences of immigrants to Australia living with diabetes

OBJECTIVES

Ageing immigrant populations now pose problems for the management of chronic illness in Australia. This article asks questions about the experiences of immigrants in Australia with type II diabetes mellitus (DM). What impact, if any, have health policies had on the lives of immigrants? How do their experiences of living with DM compare with those of people with DM who were born in Australia?

METHODS

Semi-structured interviews were conducted with 32 participants who had DM (n = 25) or cared for someone with DM (n = 7). Fifteen participants had migrated to Australia and English was not their first language. Participants were asked to describe their experience of managing diabetes.

RESULTS

Immigrants to Australia confront linguistic and cultural barriers that create an extra layer of problems not experienced by Australian-born people. Older people who were born overseas face obstacles to effective engagement with the health system that weaken their ability to take an active part in the management of their conditions.

CONCLUSIONS

Chronic disease policy is failing immigrants to Australia. Health professionals and services must recognize the central role that cultural diversity plays in self-management and the impact that this can have on health outcomes for immigrants with chronic illness.