Prediction of diabetic nephropathy: The need for a sweet biomarker

Use of Readily Accessible Inflammatory Markers to Predict Diabetic Kidney Disease

Diabetic kidney disease is a common complication of type 1 and type 2 diabetes and is the primary cause of end-stage renal disease in developed countries. Early detection of diabetic kidney disease will facilitate early intervention aimed at reducing the rate of progression to end-stage renal disease. Diabetic kidney disease has been traditionally classified based on the presence of albuminuria. More recently estimated glomerular filtration rate has also been incorporated into the staging of diabetic kidney disease. While albuminuric diabetic kidney disease is well described, the phenotype of non-albuminuric diabetic kidney disease is now widely accepted. An association between markers of inflammation and diabetic kidney disease has previously been demonstrated. Effector molecules of the innate immune system including C-reactive protein, interleukin-6, and tumor necrosis factor-α are increased in patients with diabetic kidney disease. Furthermore, renal infiltration of neutrophils, macrophages, and lymphocytes are observed in renal biopsies of patients with diabetic kidney disease. Similarly high serum neutrophil and low serum lymphocyte counts have been shown to be associated with diabetic kidney disease. The neutrophil-lymphocyte ratio is considered a robust measure of systemic inflammation and is associated with the presence of inflammatory conditions including the metabolic syndrome and insulin resistance. Cross-sectional studies have demonstrated a link between high levels of the above inflammatory biomarkers and diabetic kidney disease. Further longitudinal studies will be required to determine if these readily available inflammatory biomarkers can accurately predict the presence and prognosis of diabetic kidney disease, above and beyond albuminuria, and estimated glomerular filtration rate.

Diabetes mellitus and renal failure: Prevention and management

Nowadays, diabetes mellitus (DM) and hypertension are considered as the most common causes of end-stage renal disease (ESRD). In this paper, other than presenting the role of DM in ESRD, glucose metabolism and the management of hyperglycemia in these patients are reviewed. Although in several large studies there was no significant relationship found between tight glycemic control and the survival of ESRD patients, it is recommended that glycemic control be considered as the main therapeutic goal in the treatment of these patients to prevent damage to other organs. Glycemic control is perfect when fasting blood sugar is less than 140 mg/dL, 1-h postprandial blood glucose is less than 200 mg/dL, and glycosylated hemoglobin (HbA1c) is 6-7 in patients with type 1 diabetes and 7-8 in patients with type 2 diabetes. Administration of metformin should be avoided in chronic renal failure (CRF) because of lactic acidosis, the potentially fatal complication of metformin, but glipizide and repaglinide seem to be good choices.

Antioxidant plants and diabetes mellitus

The incidence of diabetes mellitus (DM) is increasing rapidly and it is expected to increase by 2030. Other than currently available therapeutic options, there are a lot of herbal medicines, which have been recommended for its treatment. Herbal medicines have long been used for the treatment of DM because of the advantage usually having no or less side-effects. Most of these plants have antioxidant activities and hence, prevent or treat hard curable diseases, other than having the property of combating the toxicity of toxic or other drugs. In this review other than presenting new findings of DM, the plants, which are used and have been evaluated scientifically for the treatment of DM are introduced.

Akt Links Insulin Signaling to Albumin Endocytosis in Proximal Tubule Epithelial Cells

Diabetes mellitus (DM) has become an epidemic, causing a significant decline in quality of life of individuals due to its multisystem involvement. Kidney is an important target organ in DM accounting for the majority of patients requiring renal replacement therapy at dialysis units. Microalbuminuria (MA) has been a valuable tool to predict end-organ damage in DM but its low sensitivity has driven research efforts to seek other alternatives. Albumin is taken up by albumin receptors, megalin and cubilin in the proximal tubule epithelial cells. We demonstrated that insulin at physiological concentrations induce albumin endocytosis through activation of protein kinase B (Akt) in proximal tubule epithelial cells. Inhibition of Akt by a phosphorylation deficient construct abrogated insulin induced albumin endocytosis suggesting a role for Akt in insulin-induced albumin endocytosis. Furthermore we demonstrated a novel interaction between Akt substrate 160kDa (AS160) and cytoplasmic tail of megalin. Mice with type 1 DM (T1D) displayed decreased Akt, megalin, cubilin and AS160 expression in their kidneys in association with urinary cubilin shedding preceding significant MA. Patients with T1D who have developed MA in the EDC (The Pittsburgh Epidemiology of Diabetes Complications) study demonstrated urinary cubilin shedding prior to development of MA. We hypothesize that perturbed insulin-Akt cascade in DM leads to alterations in trafficking of megalin and cubilin, which results in urinary cubilin shedding as a prelude to MA in early diabetic nephropathy. We propose that utilization of urinary cubilin shedding, as a urinary biomarker, will allow us to detect and intervene in diabetic nephropathy (DN) at an earlier stage.

Herbal versus synthetic drugs; beliefs and facts

Herbal therapy is a holistic therapy, integrating emotional, mental and spiritual levels. Life style, emotional, mental and spiritual considerations are part of any naturopathic approach. The use of herbs does not generally involve "drug" actions or adverse effects. Although medicinal plants are widely used and assumed to be safe, however, they can potentially be toxic. Where poisoning from medicinal plants has been reported, it usually has been due to misidentification of the plants in the form, in which they are sold, or incorrectly preparation and administration by inadequately trained personnel. There are some "drug like" plants remedies that their actions approach that of pharmaceuticals. Herbalists use these plants in treatment strategies and in countries such as Britain their vast availability is restricted by law. Digitalis is one of these examples and the number of these plants is not a lot. The mechanisms by which the herbs generally act are not established, however, most of medicinal plants possess antioxidant activities. The plants have been shown to effective by this property is various conditions including cancer, memory deficit and Alzheimer, atherosclerosis, diabetes and other cardiovascular diseases. Antioxidant activities of herbal medicines are also effective in reducing the toxicities of toxic agents or other drugs.

New concepts in nutraceuticals as alternative for pharmaceuticals

Nutraceuticals are products, which other than nutrition are also used as medicine. A nutraceutical product may be defined as a substance, which has physiological benefit or provides protection against chronic disease. Nutraceuticals may be used to improve health, delay the aging process, prevent chronic diseases, increase life expectancy, or support the structure or function of the body. Nowadays, nutraceuticals have received considerable interest due to potential nutritional, safety and therapeutic effects. Recent studies have shown promising results for these compounds in various complications. In the present review much effort has been devoted to present new concepts about nutraceuticals based on their diseases modifying indications. Emphasis has been made to present herbal nutraceuticals effective on hard curative disorders related to oxidative stress including allergy, alzheimer, cardiovascular, cancer, diabetes, eye, immune, inflammatory and Parkinson's diseases as well as obesity. The recently published papers about different aspects of nutraceuticals as alternative for pharmaceuticals were searched using scientific sites such as Medline, PubMed, and Google Scholar. The used terms included nutraceutical and allergy, alzheimer, cardiovascular, cancer, diabetes, eye, immune, inflammatory or Parkinson.

Metformin and diabetic kidney disease: a mini-review on recent findings

Metformin, an oral anti-diabetic agent in the biguanide class is a widely prescribed drug to treat high blood glucose in patients with type 2 diabetes mellitus. Metformin has three different roles, including blood glucose regulatory effect, protection of kidney tubular cell by acting as an effective antioxidant and finally ameliorative effect on diabetic kidney disease through saving the podocytes. Therefore, diabetic patients may benefit from all of these three distinct ameliorative effects.

Metformin: Current knowledge

Diabetes mellitus is a group of metabolic disorders in which the blood glucose is higher than normal levels, due to insufficiency of insulin release or improper response of cells to insulin, resulting in high blood pressure. The resultant hyperglycemia produces sever complications. Metformin drug has been shown to prevent diabetes in people who are at high risk and decrease most of the diabetic complications. Recent reports on metformin, not only indicate some implications such as renoprotective properties have been suggested for metformin, but some reports indicate its adverse effects as well that are negligible when its benefits are brought into account. We aimed here to review the new implications of metformin and discuss about the concerns in the use of metformin, referring to the recently published papers.

Association of serum lipids with level of blood pressure in type 2 diabetic patients

Introduction: Dyslipidemia and high blood pressure in diabetic patients increase the risk of microvascular and macrovascular complications.

Objectives: This study was conducted to investigate the association between serum lipids and level of blood pressure in type 2 diabetic patients (T2D).

Patients and Methods: A prospective analytical study was carried out in 60 patients with T2D of both genders. None of the patients had a history of hypertension, and none was treated with antihypertensive drugs. Resting systolic blood pressures and fifth phase diastolic blood pressures were measured three times while the subjects were seated, and the results were averaged second and third measurements. Sixty patients with T2D were enrolled to the study. None of the patients who had a history of gout, was treated with allopurinol or treated with antihypertensive drugs previously.

Results: Of 60 participants, mean of serum creatinine was 0.98±0.22 mg/dL. Mean of systolic and diastolic blood pressure was 133±13 mmHg and 84±7.4 mmHg respectively. In this study, a significant positive correlation of serum cholesterol with systolic (r=0.598, p=0.001) and diastolic blood pressure (r=0.584, p=0.001) was seen. Also the associations of serum LDL-C with systolic and diastolic blood pressure were as follow (r = 0.335, p<0.001) and (0.491, p<0.001) respectively. Associations of HDL-C with systolic and diastolic blood pressure were not significance as follow -0.05 and 0.04 respectively.

Conclusion: The results of this study suggest that serum cholesterol has a strong association with levels of systolic and diastolic blood pressure in T2D patients. More attention to serum lipids and treatment of dyslipidemia could halt the progress of diabetic kidney disease.

Suppressive impact of anethum graveolens consumption on biochemical risk factors of atherosclerosis in hypercholesterolemic rabbits

BACKGROUND

We aimed to determine the effects of Anethum graveolens (Dill) powder on postprandial lipid profile, markers of oxidation and endothelial activation when added to a fatty meal.

METHODS

In an experimental study, 32 rabbits were randomly designated into four diet groups: normal diet, high cholesterol diet (1%), high cholesterol diet plus 5% (w/w) dill powder and high cholesterol diet plus lovastatin (10 mg/kg, bw). The concentrations of glucose, total cholesterol (TC), low-density lipoproteins-cholesterol (LDL-C), alanine aminotransferase (alt), aspartate aminotransferase (ast), fibrinogen, factor VII, apolipoprotein B (ApoB), nitrite and nitrate were measured in blood samples following 15 h of fasting and 3 h after feeding.

RESULTS

Concurrent use of A. graveolens powder or lovastatin significantly decreased ALT, TC, glucose, fibrinogen and LDL-C values in comparison with hypercholesterolemic diet group (P < 0.05). Consumption of A. graveolens or lovastatin did not change factor VII, ApoB, nitrite and nitrate levels significantly in comparison with hypercholesterolemic diet group. Intake of A. graveolens significantly decreased serum AST compared to hypercholesterolemic diet.

CONCLUSIONS

A. graveolens might have some protective values against atherosclerosis and that it significantly affects some biochemical risk factors of this disease. Our findings also confirm the potential harmful effects of oxidized fats and the importance of dietary polyphenols in the meal.

Renoprotective effects of metformin

Metformin as a biguanid drug entered to the market 50 years ago and now is generally recommended as the first-line treatment in type 2 diabetes, especially in overweight patients, however in recent years new indications for its use have emerged . It improves peripheral and liver sensitivity to insulin, reduces basal hepatic glucose production, increases insulin-stimulated uptake and utilization of glucose by peripheral tissues, decreases hunger and causes weight reduction.Recently, much attention has been made toward the possible kidney protective efficacy of metformin. Recent studies have proven that metformin, possesses antioxidant properties, too.

Efficacy of Co-administration of Garlic Extract and Metformin for Prevention of Gentamicin-Renal Toxicity in Wistar Rats: A Biochemical Study

BACKGROUND

Gentamicin (GM) nephrotoxicity has been related to oxidative stress. Garlic and metformin (MF) have anti-oxadant activity and therefore, this study was aimed to evaluate the preventive and curative effects of garlic, MF and their combination on GM indeced tubular toxicity in Wistar rats.

METHODS

In a pre-clinical study, 70 male Wistar rats were randomly designated into 7 groups of 10 and treated as follows: Group 1: Received saline for 20 days. Group 2: Were injected 100 mg/kg/d of GM intraperitoneally (ip), for 10 days and saline for 10 more days. Group 3: Received GM for 10 days then 20 mg/kg garlic ip for the next 10 days. Group 4: Received GM for 10 days and MF (100 mg/kg) orally for the next 10 days. Group 5: Received GM for 10 days and a combination of MF and garlic for the next 10 days (100 and 20 mg/kg, respectively). Group 6: The same as group 5but with half-doses of MF and Garlic. Group 7: Received GM for 10 days together with a combination ofMF and garlic. On 20(th) day of the experiment the serum blood urea nitrogen (BUN) and creatinine (Cr) were measured and compared in different groups.

RESULTS

GM injection significantly increased the serum BUN and Cr (P < 0.05). Administration of MF, garlic or their combination with or after injection of GM (high doses) could atenuate BUN and Cr.

CONCLUSIONS

The results indicate that MF and garlic or their combination have curative and protective activity against GM nephrotoxicity.

Association of serum uric acid with proteinuria in type 2 diabetic patients

BACKGROUND

Various findings suggest that uric acid is an inflammatory factor and may have a role in endothelial dysfunction and act as a mediator of diabetic nephropathy. The objective of this study was to evaluate the relationships between serum uric acid level and level of proteinuria in type 2 diabetic (T2D) patients.

MATERIALS AND METHODS

A cross-sectional analytical study was conducted in 60 patients with T2D without a history of gout. None was treated with allopurinol. Venous blood samples were obtained in fasting state for determinations of serum creatinine, uric acid, and hemoglobin A1c (HbA1c) (reference range 3.8-5.5%); 24-h urine proteinuria was also measured.

RESULTS

Mean age of the patients was 57 ± 8.3 years. Mean ± standard error (SE) of serum creatinine was 0.98 ± 0.028 mg/dL, mean ± SE of serum uric acid was 4.5 ± 0.15 mg/dL, and mean ± SE of proteinuria was 388 ± 28.7 mg/day (median = 303.5 mg/day). There was no significant difference in serum uric acid, HbA1c, and creatinine level between males and females (P > 0.05). There was a significant positive association between body mass index (BMI) and serum uric acid levels (r = 0.428, P = 0.001). After adjustment for weight, a significant positive association of serum uric acid with level of proteinuria was seen (r = 0.47, P < 0.001).

CONCLUSION

Serum uric acid had a significant positive association with diabetic nephropathy. It might be hypothesized that serum uric acid plays a role in diabetic nephropathy in T2D.